Merge branch 'dev' into patch

* Use the correct heuristic to avoid checking for next pruning point movement when not needed

.github/workflows/SetPageFileSize.ps1

@@ -11,8 +11,8 @@
 #>
 
 param(
-    [System.UInt64] $MinimumSize = 8gb ,
-    [System.UInt64] $MaximumSize = 8gb ,
+    [System.UInt64] $MinimumSize = 16gb ,
+    [System.UInt64] $MaximumSize = 16gb ,
     [System.String] $DiskRoot = "D:"
 )
 

.github/workflows/deploy.yaml

@@ -1,7 +1,7 @@
-name: Build and Upload assets
+name: Build and upload assets
 on:
   release:
-    types: [published]
+    types: [ published ]
 
 jobs:
   build:
@@ -10,34 +10,33 @@ jobs:
       fail-fast: false
       matrix:
         os: [ ubuntu-latest, windows-latest, macos-latest ]
-    name: Building For ${{ matrix.os }}
+    name: Building, ${{ matrix.os }}
     steps:
-      - name: Fix windows CRLF
+      - name: Fix CRLF on Windows
+        if: runner.os == 'Windows'
         run: git config --global core.autocrlf false
 
       - name: Check out code into the Go module directory
         uses: actions/checkout@v2
 
-      # We need to increase the page size because the tests run out of memory on github CI windows.
-      # Use the powershell script from this github action: https://github.com/al-cheb/configure-pagefile-action/blob/master/scripts/SetPageFileSize.ps1
-      # MIT License (MIT) Copyright (c) 2020 Maxim Lobanov and contributors
-      - name: Increase page size on windows
+      # Increase the pagefile size on Windows to aviod running out of memory
+      - name: Increase pagefile size on Windows
         if: runner.os == 'Windows'
-        shell: powershell
-        run: powershell -command .\.github\workflows\SetPageFileSize.ps1
+        run: powershell -command .github\workflows\SetPageFileSize.ps1
 
 
-      - name: Set up Go 1.x
+      - name: Setup Go
         uses: actions/setup-go@v2
         with:
           go-version: 1.16
 
-      - name: Build on linux
+      - name: Build on Linux
         if: runner.os == 'Linux'
-        # `-extldflags=-static` - means static link everything, `-tags netgo,osusergo` means use pure go replacements for "os/user" and "net"
+        # `-extldflags=-static` - means static link everything,
+        # `-tags netgo,osusergo` means use pure go replacements for "os/user" and "net"
         # `-s -w` strips the binary to produce smaller size binaries
         run: |
-          go build -v -ldflags="-s -w -extldflags=-static" -tags netgo,osusergo -o ./bin/ ./...
+          go build -v -ldflags="-s -w -extldflags=-static" -tags netgo,osusergo -o ./bin/ . ./cmd/...
           archive="bin/kaspad-${{ github.event.release.tag_name }}-linux.zip"
           asset_name="kaspad-${{ github.event.release.tag_name }}-linux.zip"
           zip -r "${archive}" ./bin/*
@@ -48,7 +47,7 @@ jobs:
         if: runner.os == 'Windows'
         shell: bash
         run: |
-          go build -v -ldflags="-s -w" -o bin/ ./...
+          go build -v -ldflags="-s -w" -o bin/ . ./cmd/...
           archive="bin/kaspad-${{ github.event.release.tag_name }}-win64.zip"
           asset_name="kaspad-${{ github.event.release.tag_name }}-win64.zip"
           powershell "Compress-Archive bin/* \"${archive}\""
@@ -58,7 +57,7 @@ jobs:
       - name: Build on MacOS
         if: runner.os == 'macOS'
         run: |
-          go build -v -ldflags="-s -w" -o ./bin/ ./...
+          go build -v -ldflags="-s -w" -o ./bin/ . ./cmd/...
           archive="bin/kaspad-${{ github.event.release.tag_name }}-osx.zip"
           asset_name="kaspad-${{ github.event.release.tag_name }}-osx.zip"
           zip -r "${archive}" ./bin/*
@@ -66,7 +65,7 @@ jobs:
           echo "asset_name=${asset_name}" >> $GITHUB_ENV
 
 
-      - name: Upload Release Asset
+      - name: Upload release asset
         uses: actions/upload-release-asset@v1
         env:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}

.github/workflows/race.yaml

@@ -1,4 +1,4 @@
-name: Go-Race
+name: Race
 
 on:
   schedule:
@@ -7,7 +7,7 @@ on:
 
 jobs:
   race_test:
-    runs-on: ubuntu-20.04
+    runs-on: ubuntu-latest
     strategy:
       fail-fast: false
       matrix:
@@ -19,10 +19,10 @@ jobs:
         with:
           fetch-depth: 0
 
-      - name: Set up Go 1.x
+      - name: Setup Go
         uses: actions/setup-go@v2
         with:
-          go-version: 1.15
+          go-version: 1.16
 
       - name: Set scheduled branch name
         shell: bash
@@ -46,4 +46,4 @@ jobs:
         run: |
           git checkout "${{ env.run_on }}"
           git status
-          go test -race ./...
+          go test -timeout 20m -race ./...

.github/workflows/tests.yaml

@@ -1,38 +1,36 @@
-name: Go
+name: Tests
 
 on:
   push:
   pull_request:
-    # edtited - "title, body, or the base branch of the PR is modified"
-    # synchronize - "commit(s) pushed to the pull request"
-    types: [opened, synchronize, edited, reopened]
+    # edtited - because base branch can be modified
+    # synchronize - update commits on PR
+    types: [opened, synchronize, edited]
 
 jobs:
+
   build:
     runs-on: ${{ matrix.os }}
     strategy:
       fail-fast: false
       matrix:
-        os: [ ubuntu-16.04, macos-10.15, windows-2019 ]
-    name: Testing on on ${{ matrix.os }}
+        os: [ ubuntu-latest, macos-latest ]
+    name: Tests, ${{ matrix.os }}
     steps:
 
-      - name: Fix windows CRLF
+      - name: Fix CRLF on Windows
+        if: runner.os == 'Windows'
         run: git config --global core.autocrlf false
 
       - name: Check out code into the Go module directory
         uses: actions/checkout@v2
 
-      # We need to increase the page size because the tests run out of memory on github CI windows.
-      # Use the powershell script from this github action: https://github.com/al-cheb/configure-pagefile-action/blob/master/scripts/SetPageFileSize.ps1
-      # MIT License (MIT) Copyright (c) 2020 Maxim Lobanov and contributors
-      - name: Increase page size on windows
+      # Increase the pagefile size on Windows to aviod running out of memory
+      - name: Increase pagefile size on Windows
         if: runner.os == 'Windows'
-        shell: powershell
-        run: powershell -command .\.github\workflows\SetPageFileSize.ps1
+        run: powershell -command .github\workflows\SetPageFileSize.ps1
 
-
-      - name: Set up Go 1.x
+      - name: Setup Go
         uses: actions/setup-go@v2
         with:
           go-version: 1.16
@@ -51,14 +49,41 @@ jobs:
         shell: bash
         run: ./build_and_test.sh -v
 
+
+  stability-test-fast:
+    runs-on: ubuntu-latest
+    name: Fast stability tests, ${{ github.head_ref }}
+    steps:
+
+      - name: Setup Go
+        uses: actions/setup-go@v2
+        with:
+          go-version: 1.16
+
+      - name: Checkout
+        uses: actions/checkout@v2
+        with:
+          fetch-depth: 0
+
+      - name: Install kaspad
+        run: go install ./...
+
+      - name: Install golint
+        run: go get -u golang.org/x/lint/golint
+
+      - name: Run fast stability tests
+        working-directory: stability-tests
+        run: ./install_and_test.sh
+
+
   coverage:
-    runs-on: ubuntu-20.04
+    runs-on: ubuntu-latest
     name: Produce code coverage
     steps:
       - name: Check out code into the Go module directory
         uses: actions/checkout@v2
 
-      - name: Set up Go 1.x
+      - name: Setup Go
         uses: actions/setup-go@v2
         with:
           go-version: 1.16
@@ -70,4 +95,4 @@ jobs:
         run: go test -v -covermode=atomic -coverpkg=./... -coverprofile coverage.txt ./...
 
       - name: Upload coverage file
-        run: bash <(curl -s https://codecov.io/bash)
+        run: bash <(curl -s https://codecov.io/bash)

CONTRIBUTING.md

@@ -12,8 +12,7 @@ If you want to make a big change it's better to discuss it first by opening an i
 
 ## Pull Request process
 
-Any pull request should be opened against the development branch of the target version. The development branch format is
-as follows: `vx.y.z-dev`, for example: `v0.8.5-dev`.
+Any pull request should be opened against the development branch `dev`.
 
 All pull requests should pass the checks written in `build_and_test.sh`, so it's recommended to run this script before
 submitting your PR.

README.md

@@ -1,16 +1,13 @@
 
 Kaspad
 ====
-Warning: This is pre-alpha software. There's no guarantee anything works.
-====
 
 [![ISC License](http://img.shields.io/badge/license-ISC-blue.svg)](https://choosealicense.com/licenses/isc/)
 [![GoDoc](https://img.shields.io/badge/godoc-reference-blue.svg)](http://godoc.org/github.com/kaspanet/kaspad)
 
 Kaspad is the reference full node Kaspa implementation written in Go (golang).
 
-This project is currently under active development and is in a pre-Alpha state.
-Some things still don't work and APIs are far from finalized. The code is provided for reference only.
+This project is currently under active development and is in Beta state.
 
 ## What is kaspa
 
@@ -63,6 +60,8 @@ Join our discord server using the following link: https://discord.gg/YNYnNN5Pf2
 The [integrated github issue tracker](https://github.com/kaspanet/kaspad/issues)
 is used for this project.
 
+Issue priorities may be seen at https://github.com/orgs/kaspanet/projects/4
+
 ## Documentation
 
 The [documentation](https://github.com/kaspanet/docs) is a work-in-progress

app/app.go

@@ -20,7 +20,10 @@ import (
 	"github.com/kaspanet/kaspad/version"
 )
 
-const leveldbCacheSizeMiB = 256
+const (
+	leveldbCacheSizeMiB = 256
+	defaultDataDirname  = "datadir2"
+)
 
 var desiredLimits = &limits.DesiredLimits{
 	FileLimitWant: 2048,
@@ -84,6 +87,7 @@ func (app *kaspadApp) main(startedChan chan<- struct{}) error {
 	if app.cfg.Profile != "" {
 		profiling.Start(app.cfg.Profile, log)
 	}
+	profiling.TrackHeap(app.cfg.AppDir, log)
 
 	// Return now if an interrupt signal was triggered.
 	if signal.InterruptRequested(interrupt) {
@@ -101,7 +105,7 @@ func (app *kaspadApp) main(startedChan chan<- struct{}) error {
 	// Open the database
 	databaseContext, err := openDB(app.cfg)
 	if err != nil {
-		log.Error(err)
+		log.Errorf("Loading database failed: %+v", err)
 		return err
 	}
 
@@ -159,7 +163,7 @@ func (app *kaspadApp) main(startedChan chan<- struct{}) error {
 
 // dbPath returns the path to the block database given a database type.
 func databasePath(cfg *config.Config) string {
-	return filepath.Join(cfg.AppDir, "data")
+	return filepath.Join(cfg.AppDir, defaultDataDirname)
 }
 
 func removeDatabase(cfg *config.Config) error {

app/appmessage/domainconverters.go

@@ -2,6 +2,9 @@ package appmessage
 
 import (
 	"encoding/hex"
+	"github.com/pkg/errors"
+	"math/big"
+
 	"github.com/kaspanet/kaspad/domain/consensus/utils/blockheader"
 	"github.com/kaspanet/kaspad/domain/consensus/utils/hashes"
 	"github.com/kaspanet/kaspad/domain/consensus/utils/utxo"
@@ -28,13 +31,17 @@ func DomainBlockToMsgBlock(domainBlock *externalapi.DomainBlock) *MsgBlock {
 func DomainBlockHeaderToBlockHeader(domainBlockHeader externalapi.BlockHeader) *MsgBlockHeader {
 	return &MsgBlockHeader{
 		Version:              domainBlockHeader.Version(),
-		ParentHashes:         domainBlockHeader.ParentHashes(),
+		Parents:              domainBlockHeader.Parents(),
 		HashMerkleRoot:       domainBlockHeader.HashMerkleRoot(),
 		AcceptedIDMerkleRoot: domainBlockHeader.AcceptedIDMerkleRoot(),
 		UTXOCommitment:       domainBlockHeader.UTXOCommitment(),
 		Timestamp:            mstime.UnixMilliseconds(domainBlockHeader.TimeInMilliseconds()),
 		Bits:                 domainBlockHeader.Bits(),
 		Nonce:                domainBlockHeader.Nonce(),
+		BlueScore:            domainBlockHeader.BlueScore(),
+		DAAScore:             domainBlockHeader.DAAScore(),
+		BlueWork:             domainBlockHeader.BlueWork(),
+		PruningPoint:         domainBlockHeader.PruningPoint(),
 	}
 }
 
@@ -55,13 +62,17 @@ func MsgBlockToDomainBlock(msgBlock *MsgBlock) *externalapi.DomainBlock {
 func BlockHeaderToDomainBlockHeader(blockHeader *MsgBlockHeader) externalapi.BlockHeader {
 	return blockheader.NewImmutableBlockHeader(
 		blockHeader.Version,
-		blockHeader.ParentHashes,
+		blockHeader.Parents,
 		blockHeader.HashMerkleRoot,
 		blockHeader.AcceptedIDMerkleRoot,
 		blockHeader.UTXOCommitment,
 		blockHeader.Timestamp.UnixMilliseconds(),
 		blockHeader.Bits,
 		blockHeader.Nonce,
+		blockHeader.DAAScore,
+		blockHeader.BlueScore,
+		blockHeader.BlueWork,
+		blockHeader.PruningPoint,
 	)
 }
 
@@ -100,6 +111,7 @@ func domainTransactionInputToTxIn(domainTransactionInput *externalapi.DomainTran
 		PreviousOutpoint: *domainOutpointToOutpoint(domainTransactionInput.PreviousOutpoint),
 		SignatureScript:  domainTransactionInput.SignatureScript,
 		Sequence:         domainTransactionInput.Sequence,
+		SigOpCount:       domainTransactionInput.SigOpCount,
 	}
 }
 
@@ -148,6 +160,7 @@ func txInToDomainTransactionInput(txIn *TxIn) *externalapi.DomainTransactionInpu
 	return &externalapi.DomainTransactionInput{
 		PreviousOutpoint: *outpointToDomainOutpoint(&txIn.PreviousOutpoint), //TODO
 		SignatureScript:  txIn.SignatureScript,
+		SigOpCount:       txIn.SigOpCount,
 		Sequence:         txIn.Sequence,
 	}
 }
@@ -163,14 +176,10 @@ func outpointToDomainOutpoint(outpoint *Outpoint) *externalapi.DomainOutpoint {
 func RPCTransactionToDomainTransaction(rpcTransaction *RPCTransaction) (*externalapi.DomainTransaction, error) {
 	inputs := make([]*externalapi.DomainTransactionInput, len(rpcTransaction.Inputs))
 	for i, input := range rpcTransaction.Inputs {
-		transactionID, err := transactionid.FromString(input.PreviousOutpoint.TransactionID)
+		previousOutpoint, err := RPCOutpointToDomainOutpoint(input.PreviousOutpoint)
 		if err != nil {
 			return nil, err
 		}
-		previousOutpoint := &externalapi.DomainOutpoint{
-			TransactionID: *transactionID,
-			Index:         input.PreviousOutpoint.Index,
-		}
 		signatureScript, err := hex.DecodeString(input.SignatureScript)
 		if err != nil {
 			return nil, err
@@ -179,6 +188,7 @@ func RPCTransactionToDomainTransaction(rpcTransaction *RPCTransaction) (*externa
 			PreviousOutpoint: *previousOutpoint,
 			SignatureScript:  signatureScript,
 			Sequence:         input.Sequence,
+			SigOpCount:       input.SigOpCount,
 		}
 	}
 	outputs := make([]*externalapi.DomainTransactionOutput, len(rpcTransaction.Outputs))
@@ -213,6 +223,36 @@ func RPCTransactionToDomainTransaction(rpcTransaction *RPCTransaction) (*externa
 	}, nil
 }
 
+// RPCOutpointToDomainOutpoint converts RPCOutpoint to  DomainOutpoint
+func RPCOutpointToDomainOutpoint(outpoint *RPCOutpoint) (*externalapi.DomainOutpoint, error) {
+	transactionID, err := transactionid.FromString(outpoint.TransactionID)
+	if err != nil {
+		return nil, err
+	}
+	return &externalapi.DomainOutpoint{
+		TransactionID: *transactionID,
+		Index:         outpoint.Index,
+	}, nil
+}
+
+// RPCUTXOEntryToUTXOEntry converts RPCUTXOEntry to UTXOEntry
+func RPCUTXOEntryToUTXOEntry(entry *RPCUTXOEntry) (externalapi.UTXOEntry, error) {
+	script, err := hex.DecodeString(entry.ScriptPublicKey.Script)
+	if err != nil {
+		return nil, err
+	}
+
+	return utxo.NewUTXOEntry(
+		entry.Amount,
+		&externalapi.ScriptPublicKey{
+			Script:  script,
+			Version: entry.ScriptPublicKey.Version,
+		},
+		entry.IsCoinbase,
+		entry.BlockDAAScore,
+	), nil
+}
+
 // DomainTransactionToRPCTransaction converts DomainTransactions to RPCTransactions
 func DomainTransactionToRPCTransaction(transaction *externalapi.DomainTransaction) *RPCTransaction {
 	inputs := make([]*RPCTransactionInput, len(transaction.Inputs))
@@ -227,6 +267,7 @@ func DomainTransactionToRPCTransaction(transaction *externalapi.DomainTransactio
 			PreviousOutpoint: previousOutpoint,
 			SignatureScript:  signatureScript,
 			Sequence:         input.Sequence,
+			SigOpCount:       input.SigOpCount,
 		}
 	}
 	outputs := make([]*RPCTransactionOutput, len(transaction.Outputs))
@@ -257,22 +298,27 @@ func OutpointAndUTXOEntryPairsToDomainOutpointAndUTXOEntryPairs(
 
 	domainOutpointAndUTXOEntryPairs := make([]*externalapi.OutpointAndUTXOEntryPair, len(outpointAndUTXOEntryPairs))
 	for i, outpointAndUTXOEntryPair := range outpointAndUTXOEntryPairs {
-		domainOutpointAndUTXOEntryPairs[i] = &externalapi.OutpointAndUTXOEntryPair{
-			Outpoint: &externalapi.DomainOutpoint{
-				TransactionID: outpointAndUTXOEntryPair.Outpoint.TxID,
-				Index:         outpointAndUTXOEntryPair.Outpoint.Index,
-			},
-			UTXOEntry: utxo.NewUTXOEntry(
-				outpointAndUTXOEntryPair.UTXOEntry.Amount,
-				outpointAndUTXOEntryPair.UTXOEntry.ScriptPublicKey,
-				outpointAndUTXOEntryPair.UTXOEntry.IsCoinbase,
-				outpointAndUTXOEntryPair.UTXOEntry.BlockDAAScore,
-			),
-		}
+		domainOutpointAndUTXOEntryPairs[i] = outpointAndUTXOEntryPairToDomainOutpointAndUTXOEntryPair(outpointAndUTXOEntryPair)
 	}
 	return domainOutpointAndUTXOEntryPairs
 }
 
+func outpointAndUTXOEntryPairToDomainOutpointAndUTXOEntryPair(
+	outpointAndUTXOEntryPair *OutpointAndUTXOEntryPair) *externalapi.OutpointAndUTXOEntryPair {
+	return &externalapi.OutpointAndUTXOEntryPair{
+		Outpoint: &externalapi.DomainOutpoint{
+			TransactionID: outpointAndUTXOEntryPair.Outpoint.TxID,
+			Index:         outpointAndUTXOEntryPair.Outpoint.Index,
+		},
+		UTXOEntry: utxo.NewUTXOEntry(
+			outpointAndUTXOEntryPair.UTXOEntry.Amount,
+			outpointAndUTXOEntryPair.UTXOEntry.ScriptPublicKey,
+			outpointAndUTXOEntryPair.UTXOEntry.IsCoinbase,
+			outpointAndUTXOEntryPair.UTXOEntry.BlockDAAScore,
+		),
+	}
+}
+
 // DomainOutpointAndUTXOEntryPairsToOutpointAndUTXOEntryPairs converts
 // domain OutpointAndUTXOEntryPairs to OutpointAndUTXOEntryPairs
 func DomainOutpointAndUTXOEntryPairsToOutpointAndUTXOEntryPairs(
@@ -298,15 +344,25 @@ func DomainOutpointAndUTXOEntryPairsToOutpointAndUTXOEntryPairs(
 
 // DomainBlockToRPCBlock converts DomainBlocks to RPCBlocks
 func DomainBlockToRPCBlock(block *externalapi.DomainBlock) *RPCBlock {
+	parents := make([]*RPCBlockLevelParents, len(block.Header.Parents()))
+	for i, blockLevelParents := range block.Header.Parents() {
+		parents[i] = &RPCBlockLevelParents{
+			ParentHashes: hashes.ToStrings(blockLevelParents),
+		}
+	}
 	header := &RPCBlockHeader{
 		Version:              uint32(block.Header.Version()),
-		ParentHashes:         hashes.ToStrings(block.Header.ParentHashes()),
+		Parents:              parents,
 		HashMerkleRoot:       block.Header.HashMerkleRoot().String(),
 		AcceptedIDMerkleRoot: block.Header.AcceptedIDMerkleRoot().String(),
 		UTXOCommitment:       block.Header.UTXOCommitment().String(),
 		Timestamp:            block.Header.TimeInMilliseconds(),
 		Bits:                 block.Header.Bits(),
 		Nonce:                block.Header.Nonce(),
+		DAAScore:             block.Header.DAAScore(),
+		BlueScore:            block.Header.BlueScore(),
+		BlueWork:             block.Header.BlueWork().Text(16),
+		PruningPoint:         block.Header.PruningPoint().String(),
 	}
 	transactions := make([]*RPCTransaction, len(block.Transactions))
 	for i, transaction := range block.Transactions {
@@ -320,13 +376,16 @@ func DomainBlockToRPCBlock(block *externalapi.DomainBlock) *RPCBlock {
 
 // RPCBlockToDomainBlock converts `block` into a DomainBlock
 func RPCBlockToDomainBlock(block *RPCBlock) (*externalapi.DomainBlock, error) {
-	parentHashes := make([]*externalapi.DomainHash, len(block.Header.ParentHashes))
-	for i, parentHash := range block.Header.ParentHashes {
-		domainParentHashes, err := externalapi.NewDomainHashFromString(parentHash)
-		if err != nil {
-			return nil, err
+	parents := make([]externalapi.BlockLevelParents, len(block.Header.Parents))
+	for i, blockLevelParents := range block.Header.Parents {
+		parents[i] = make(externalapi.BlockLevelParents, len(blockLevelParents.ParentHashes))
+		for j, parentHash := range blockLevelParents.ParentHashes {
+			var err error
+			parents[i][j], err = externalapi.NewDomainHashFromString(parentHash)
+			if err != nil {
+				return nil, err
+			}
 		}
-		parentHashes[i] = domainParentHashes
 	}
 	hashMerkleRoot, err := externalapi.NewDomainHashFromString(block.Header.HashMerkleRoot)
 	if err != nil {
@@ -340,15 +399,27 @@ func RPCBlockToDomainBlock(block *RPCBlock) (*externalapi.DomainBlock, error) {
 	if err != nil {
 		return nil, err
 	}
+	blueWork, success := new(big.Int).SetString(block.Header.BlueWork, 16)
+	if !success {
+		return nil, errors.Errorf("failed to parse blue work: %s", block.Header.BlueWork)
+	}
+	pruningPoint, err := externalapi.NewDomainHashFromString(block.Header.PruningPoint)
+	if err != nil {
+		return nil, err
+	}
 	header := blockheader.NewImmutableBlockHeader(
 		uint16(block.Header.Version),
-		parentHashes,
+		parents,
 		hashMerkleRoot,
 		acceptedIDMerkleRoot,
 		utxoCommitment,
 		block.Header.Timestamp,
 		block.Header.Bits,
-		block.Header.Nonce)
+		block.Header.Nonce,
+		block.Header.DAAScore,
+		block.Header.BlueScore,
+		blueWork,
+		pruningPoint)
 	transactions := make([]*externalapi.DomainTransaction, len(block.Transactions))
 	for i, transaction := range block.Transactions {
 		domainTransaction, err := RPCTransactionToDomainTransaction(transaction)
@@ -362,3 +433,169 @@ func RPCBlockToDomainBlock(block *RPCBlock) (*externalapi.DomainBlock, error) {
 		Transactions: transactions,
 	}, nil
 }
+
+// BlockWithTrustedDataToDomainBlockWithTrustedData converts *MsgBlockWithTrustedData to *externalapi.BlockWithTrustedData
+func BlockWithTrustedDataToDomainBlockWithTrustedData(block *MsgBlockWithTrustedData) *externalapi.BlockWithTrustedData {
+	daaWindow := make([]*externalapi.TrustedDataDataDAAHeader, len(block.DAAWindow))
+	for i, daaBlock := range block.DAAWindow {
+		daaWindow[i] = &externalapi.TrustedDataDataDAAHeader{
+			Header:       BlockHeaderToDomainBlockHeader(&daaBlock.Block.Header),
+			GHOSTDAGData: ghostdagDataToDomainGHOSTDAGData(daaBlock.GHOSTDAGData),
+		}
+	}
+
+	ghostdagData := make([]*externalapi.BlockGHOSTDAGDataHashPair, len(block.GHOSTDAGData))
+	for i, datum := range block.GHOSTDAGData {
+		ghostdagData[i] = &externalapi.BlockGHOSTDAGDataHashPair{
+			Hash:         datum.Hash,
+			GHOSTDAGData: ghostdagDataToDomainGHOSTDAGData(datum.GHOSTDAGData),
+		}
+	}
+
+	return &externalapi.BlockWithTrustedData{
+		Block:        MsgBlockToDomainBlock(block.Block),
+		DAAWindow:    daaWindow,
+		GHOSTDAGData: ghostdagData,
+	}
+}
+
+// TrustedDataDataDAABlockV4ToTrustedDataDataDAAHeader converts *TrustedDataDAAHeader to *externalapi.TrustedDataDataDAAHeader
+func TrustedDataDataDAABlockV4ToTrustedDataDataDAAHeader(daaBlock *TrustedDataDAAHeader) *externalapi.TrustedDataDataDAAHeader {
+	return &externalapi.TrustedDataDataDAAHeader{
+		Header:       BlockHeaderToDomainBlockHeader(daaBlock.Header),
+		GHOSTDAGData: ghostdagDataToDomainGHOSTDAGData(daaBlock.GHOSTDAGData),
+	}
+}
+
+// GHOSTDAGHashPairToDomainGHOSTDAGHashPair converts *BlockGHOSTDAGDataHashPair to *externalapi.BlockGHOSTDAGDataHashPair
+func GHOSTDAGHashPairToDomainGHOSTDAGHashPair(datum *BlockGHOSTDAGDataHashPair) *externalapi.BlockGHOSTDAGDataHashPair {
+	return &externalapi.BlockGHOSTDAGDataHashPair{
+		Hash:         datum.Hash,
+		GHOSTDAGData: ghostdagDataToDomainGHOSTDAGData(datum.GHOSTDAGData),
+	}
+}
+
+func ghostdagDataToDomainGHOSTDAGData(data *BlockGHOSTDAGData) *externalapi.BlockGHOSTDAGData {
+	bluesAnticoneSizes := make(map[externalapi.DomainHash]externalapi.KType, len(data.BluesAnticoneSizes))
+	for _, pair := range data.BluesAnticoneSizes {
+		bluesAnticoneSizes[*pair.BlueHash] = pair.AnticoneSize
+	}
+	return externalapi.NewBlockGHOSTDAGData(
+		data.BlueScore,
+		data.BlueWork,
+		data.SelectedParent,
+		data.MergeSetBlues,
+		data.MergeSetReds,
+		bluesAnticoneSizes,
+	)
+}
+
+func domainGHOSTDAGDataGHOSTDAGData(data *externalapi.BlockGHOSTDAGData) *BlockGHOSTDAGData {
+	bluesAnticoneSizes := make([]*BluesAnticoneSizes, 0, len(data.BluesAnticoneSizes()))
+	for blueHash, anticoneSize := range data.BluesAnticoneSizes() {
+		blueHashCopy := blueHash
+		bluesAnticoneSizes = append(bluesAnticoneSizes, &BluesAnticoneSizes{
+			BlueHash:     &blueHashCopy,
+			AnticoneSize: anticoneSize,
+		})
+	}
+
+	return &BlockGHOSTDAGData{
+		BlueScore:          data.BlueScore(),
+		BlueWork:           data.BlueWork(),
+		SelectedParent:     data.SelectedParent(),
+		MergeSetBlues:      data.MergeSetBlues(),
+		MergeSetReds:       data.MergeSetReds(),
+		BluesAnticoneSizes: bluesAnticoneSizes,
+	}
+}
+
+// DomainBlockWithTrustedDataToBlockWithTrustedData converts *externalapi.BlockWithTrustedData to *MsgBlockWithTrustedData
+func DomainBlockWithTrustedDataToBlockWithTrustedData(block *externalapi.BlockWithTrustedData) *MsgBlockWithTrustedData {
+	daaWindow := make([]*TrustedDataDataDAABlock, len(block.DAAWindow))
+	for i, daaBlock := range block.DAAWindow {
+		daaWindow[i] = &TrustedDataDataDAABlock{
+			Block: &MsgBlock{
+				Header: *DomainBlockHeaderToBlockHeader(daaBlock.Header),
+			},
+			GHOSTDAGData: domainGHOSTDAGDataGHOSTDAGData(daaBlock.GHOSTDAGData),
+		}
+	}
+
+	ghostdagData := make([]*BlockGHOSTDAGDataHashPair, len(block.GHOSTDAGData))
+	for i, datum := range block.GHOSTDAGData {
+		ghostdagData[i] = &BlockGHOSTDAGDataHashPair{
+			Hash:         datum.Hash,
+			GHOSTDAGData: domainGHOSTDAGDataGHOSTDAGData(datum.GHOSTDAGData),
+		}
+	}
+
+	return &MsgBlockWithTrustedData{
+		Block:        DomainBlockToMsgBlock(block.Block),
+		DAAScore:     block.Block.Header.DAAScore(),
+		DAAWindow:    daaWindow,
+		GHOSTDAGData: ghostdagData,
+	}
+}
+
+// DomainBlockWithTrustedDataToBlockWithTrustedDataV4 converts a set of *externalapi.DomainBlock, daa window indices and ghostdag data indices
+// to *MsgBlockWithTrustedDataV4
+func DomainBlockWithTrustedDataToBlockWithTrustedDataV4(block *externalapi.DomainBlock, daaWindowIndices, ghostdagDataIndices []uint64) *MsgBlockWithTrustedDataV4 {
+	return &MsgBlockWithTrustedDataV4{
+		Block:               DomainBlockToMsgBlock(block),
+		DAAWindowIndices:    daaWindowIndices,
+		GHOSTDAGDataIndices: ghostdagDataIndices,
+	}
+}
+
+// DomainTrustedDataToTrustedData converts *externalapi.BlockWithTrustedData to *MsgBlockWithTrustedData
+func DomainTrustedDataToTrustedData(domainDAAWindow []*externalapi.TrustedDataDataDAAHeader, domainGHOSTDAGData []*externalapi.BlockGHOSTDAGDataHashPair) *MsgTrustedData {
+	daaWindow := make([]*TrustedDataDAAHeader, len(domainDAAWindow))
+	for i, daaBlock := range domainDAAWindow {
+		daaWindow[i] = &TrustedDataDAAHeader{
+			Header:       DomainBlockHeaderToBlockHeader(daaBlock.Header),
+			GHOSTDAGData: domainGHOSTDAGDataGHOSTDAGData(daaBlock.GHOSTDAGData),
+		}
+	}
+
+	ghostdagData := make([]*BlockGHOSTDAGDataHashPair, len(domainGHOSTDAGData))
+	for i, datum := range domainGHOSTDAGData {
+		ghostdagData[i] = &BlockGHOSTDAGDataHashPair{
+			Hash:         datum.Hash,
+			GHOSTDAGData: domainGHOSTDAGDataGHOSTDAGData(datum.GHOSTDAGData),
+		}
+	}
+
+	return &MsgTrustedData{
+		DAAWindow:    daaWindow,
+		GHOSTDAGData: ghostdagData,
+	}
+}
+
+// MsgPruningPointProofToDomainPruningPointProof converts *MsgPruningPointProof to *externalapi.PruningPointProof
+func MsgPruningPointProofToDomainPruningPointProof(pruningPointProofMessage *MsgPruningPointProof) *externalapi.PruningPointProof {
+	headers := make([][]externalapi.BlockHeader, len(pruningPointProofMessage.Headers))
+	for blockLevel, blockLevelParents := range pruningPointProofMessage.Headers {
+		headers[blockLevel] = make([]externalapi.BlockHeader, len(blockLevelParents))
+		for i, header := range blockLevelParents {
+			headers[blockLevel][i] = BlockHeaderToDomainBlockHeader(header)
+		}
+	}
+	return &externalapi.PruningPointProof{
+		Headers: headers,
+	}
+}
+
+// DomainPruningPointProofToMsgPruningPointProof converts *externalapi.PruningPointProof to *MsgPruningPointProof
+func DomainPruningPointProofToMsgPruningPointProof(pruningPointProof *externalapi.PruningPointProof) *MsgPruningPointProof {
+	headers := make([][]*MsgBlockHeader, len(pruningPointProof.Headers))
+	for blockLevel, blockLevelParents := range pruningPointProof.Headers {
+		headers[blockLevel] = make([]*MsgBlockHeader, len(blockLevelParents))
+		for i, header := range blockLevelParents {
+			headers[blockLevel][i] = DomainBlockHeaderToBlockHeader(header)
+		}
+	}
+	return &MsgPruningPointProof{
+		Headers: headers,
+	}
+}

app/appmessage/error.go

@@ -38,6 +38,10 @@ type RPCError struct {
 	Message string
 }
 
+func (err RPCError) Error() string {
+	return err.Message
+}
+
 // RPCErrorf formats according to a format specifier and returns the string
 // as an RPCError.
 func RPCErrorf(format string, args ...interface{}) *RPCError {

app/appmessage/message.go

@@ -45,24 +45,30 @@ const (
 	CmdRequestRelayBlocks
 	CmdInvTransaction
 	CmdRequestTransactions
-	CmdIBDBlock
 	CmdDoneHeaders
 	CmdTransactionNotFound
 	CmdReject
-	CmdHeader
 	CmdRequestNextHeaders
-	CmdRequestPruningPointUTXOSetAndBlock
+	CmdRequestPruningPointUTXOSet
 	CmdPruningPointUTXOSetChunk
-	CmdRequestIBDBlocks
 	CmdUnexpectedPruningPoint
-	CmdRequestPruningPointHash
-	CmdPruningPointHash
 	CmdIBDBlockLocator
 	CmdIBDBlockLocatorHighestHash
 	CmdIBDBlockLocatorHighestHashNotFound
 	CmdBlockHeaders
 	CmdRequestNextPruningPointUTXOSetChunk
 	CmdDonePruningPointUTXOSetChunks
+	CmdBlockWithTrustedData
+	CmdDoneBlocksWithTrustedData
+	CmdRequestPruningPointAndItsAnticone
+	CmdIBDBlock
+	CmdRequestIBDBlocks
+	CmdPruningPoints
+	CmdRequestPruningPointProof
+	CmdPruningPointProof
+	CmdReady
+	CmdTrustedData
+	CmdBlockWithTrustedDataV4
 
 	// rpc
 	CmdGetCurrentNetworkRequestMessage
@@ -121,6 +127,8 @@ const (
 	CmdStopNotifyingUTXOsChangedResponseMessage
 	CmdGetUTXOsByAddressesRequestMessage
 	CmdGetUTXOsByAddressesResponseMessage
+	CmdGetBalanceByAddressRequestMessage
+	CmdGetBalanceByAddressResponseMessage
 	CmdGetVirtualSelectedParentBlueScoreRequestMessage
 	CmdGetVirtualSelectedParentBlueScoreResponseMessage
 	CmdNotifyVirtualSelectedParentBlueScoreChangedRequestMessage
@@ -137,6 +145,13 @@ const (
 	CmdPruningPointUTXOSetOverrideNotificationMessage
 	CmdStopNotifyingPruningPointUTXOSetOverrideRequestMessage
 	CmdStopNotifyingPruningPointUTXOSetOverrideResponseMessage
+	CmdEstimateNetworkHashesPerSecondRequestMessage
+	CmdEstimateNetworkHashesPerSecondResponseMessage
+	CmdNotifyVirtualDaaScoreChangedRequestMessage
+	CmdNotifyVirtualDaaScoreChangedResponseMessage
+	CmdVirtualDaaScoreChangedNotificationMessage
+	CmdGetBalancesByAddressesRequestMessage
+	CmdGetBalancesByAddressesResponseMessage
 )
 
 // ProtocolMessageCommandToString maps all MessageCommands to their string representation
@@ -145,7 +160,7 @@ var ProtocolMessageCommandToString = map[MessageCommand]string{
 	CmdVerAck:                              "VerAck",
 	CmdRequestAddresses:                    "RequestAddresses",
 	CmdAddresses:                           "Addresses",
-	CmdRequestHeaders:                      "RequestHeaders",
+	CmdRequestHeaders:                      "CmdRequestHeaders",
 	CmdBlock:                               "Block",
 	CmdTx:                                  "Tx",
 	CmdPing:                                "Ping",
@@ -156,24 +171,30 @@ var ProtocolMessageCommandToString = map[MessageCommand]string{
 	CmdRequestRelayBlocks:                  "RequestRelayBlocks",
 	CmdInvTransaction:                      "InvTransaction",
 	CmdRequestTransactions:                 "RequestTransactions",
-	CmdIBDBlock:                            "IBDBlock",
 	CmdDoneHeaders:                         "DoneHeaders",
 	CmdTransactionNotFound:                 "TransactionNotFound",
 	CmdReject:                              "Reject",
-	CmdHeader:                              "Header",
 	CmdRequestNextHeaders:                  "RequestNextHeaders",
-	CmdRequestPruningPointUTXOSetAndBlock:  "RequestPruningPointUTXOSetAndBlock",
+	CmdRequestPruningPointUTXOSet:          "RequestPruningPointUTXOSet",
 	CmdPruningPointUTXOSetChunk:            "PruningPointUTXOSetChunk",
-	CmdRequestIBDBlocks:                    "RequestIBDBlocks",
 	CmdUnexpectedPruningPoint:              "UnexpectedPruningPoint",
-	CmdRequestPruningPointHash:             "RequestPruningPointHashHash",
-	CmdPruningPointHash:                    "PruningPointHash",
 	CmdIBDBlockLocator:                     "IBDBlockLocator",
 	CmdIBDBlockLocatorHighestHash:          "IBDBlockLocatorHighestHash",
 	CmdIBDBlockLocatorHighestHashNotFound:  "IBDBlockLocatorHighestHashNotFound",
 	CmdBlockHeaders:                        "BlockHeaders",
 	CmdRequestNextPruningPointUTXOSetChunk: "RequestNextPruningPointUTXOSetChunk",
 	CmdDonePruningPointUTXOSetChunks:       "DonePruningPointUTXOSetChunks",
+	CmdBlockWithTrustedData:                "BlockWithTrustedData",
+	CmdDoneBlocksWithTrustedData:           "DoneBlocksWithTrustedData",
+	CmdRequestPruningPointAndItsAnticone:   "RequestPruningPointAndItsAnticoneHeaders",
+	CmdIBDBlock:                            "IBDBlock",
+	CmdRequestIBDBlocks:                    "RequestIBDBlocks",
+	CmdPruningPoints:                       "PruningPoints",
+	CmdRequestPruningPointProof:            "RequestPruningPointProof",
+	CmdPruningPointProof:                   "PruningPointProof",
+	CmdReady:                               "Ready",
+	CmdTrustedData:                         "TrustedData",
+	CmdBlockWithTrustedDataV4:              "BlockWithTrustedDataV4",
 }
 
 // RPCMessageCommandToString maps all MessageCommands to their string representation
@@ -232,6 +253,8 @@ var RPCMessageCommandToString = map[MessageCommand]string{
 	CmdStopNotifyingUTXOsChangedResponseMessage:                   "StopNotifyingUTXOsChangedResponse",
 	CmdGetUTXOsByAddressesRequestMessage:                          "GetUTXOsByAddressesRequest",
 	CmdGetUTXOsByAddressesResponseMessage:                         "GetUTXOsByAddressesResponse",
+	CmdGetBalanceByAddressRequestMessage:                          "GetBalanceByAddressRequest",
+	CmdGetBalanceByAddressResponseMessage:                         "GetBalancesByAddressResponse",
 	CmdGetVirtualSelectedParentBlueScoreRequestMessage:            "GetVirtualSelectedParentBlueScoreRequest",
 	CmdGetVirtualSelectedParentBlueScoreResponseMessage:           "GetVirtualSelectedParentBlueScoreResponse",
 	CmdNotifyVirtualSelectedParentBlueScoreChangedRequestMessage:  "NotifyVirtualSelectedParentBlueScoreChangedRequest",
@@ -248,6 +271,13 @@ var RPCMessageCommandToString = map[MessageCommand]string{
 	CmdPruningPointUTXOSetOverrideNotificationMessage:             "PruningPointUTXOSetOverrideNotification",
 	CmdStopNotifyingPruningPointUTXOSetOverrideRequestMessage:     "StopNotifyingPruningPointUTXOSetOverrideRequest",
 	CmdStopNotifyingPruningPointUTXOSetOverrideResponseMessage:    "StopNotifyingPruningPointUTXOSetOverrideResponse",
+	CmdEstimateNetworkHashesPerSecondRequestMessage:               "EstimateNetworkHashesPerSecondRequest",
+	CmdEstimateNetworkHashesPerSecondResponseMessage:              "EstimateNetworkHashesPerSecondResponse",
+	CmdNotifyVirtualDaaScoreChangedRequestMessage:                 "NotifyVirtualDaaScoreChangedRequest",
+	CmdNotifyVirtualDaaScoreChangedResponseMessage:                "NotifyVirtualDaaScoreChangedResponse",
+	CmdVirtualDaaScoreChangedNotificationMessage:                  "VirtualDaaScoreChangedNotification",
+	CmdGetBalancesByAddressesRequestMessage:                       "GetBalancesByAddressesRequest",
+	CmdGetBalancesByAddressesResponseMessage:                      "GetBalancesByAddressesResponse",
 }
 
 // Message is an interface that describes a kaspa message. A type that

app/appmessage/p2p_msgblock_test.go

@@ -18,16 +18,21 @@ import (
 
 // TestBlock tests the MsgBlock API.
 func TestBlock(t *testing.T) {
-	pver := ProtocolVersion
+	pver := uint32(4)
 
 	// Block 1 header.
-	parentHashes := blockOne.Header.ParentHashes
+	parents := blockOne.Header.Parents
 	hashMerkleRoot := blockOne.Header.HashMerkleRoot
 	acceptedIDMerkleRoot := blockOne.Header.AcceptedIDMerkleRoot
 	utxoCommitment := blockOne.Header.UTXOCommitment
 	bits := blockOne.Header.Bits
 	nonce := blockOne.Header.Nonce
-	bh := NewBlockHeader(1, parentHashes, hashMerkleRoot, acceptedIDMerkleRoot, utxoCommitment, bits, nonce)
+	daaScore := blockOne.Header.DAAScore
+	blueScore := blockOne.Header.BlueScore
+	blueWork := blockOne.Header.BlueWork
+	pruningPoint := blockOne.Header.PruningPoint
+	bh := NewBlockHeader(1, parents, hashMerkleRoot, acceptedIDMerkleRoot, utxoCommitment, bits, nonce,
+		daaScore, blueScore, blueWork, pruningPoint)
 
 	// Ensure the command is expected value.
 	wantCmd := MessageCommand(5)
@@ -131,7 +136,7 @@ func TestConvertToPartial(t *testing.T) {
 var blockOne = MsgBlock{
 	Header: MsgBlockHeader{
 		Version:              0,
-		ParentHashes:         []*externalapi.DomainHash{mainnetGenesisHash, simnetGenesisHash},
+		Parents:              []externalapi.BlockLevelParents{[]*externalapi.DomainHash{mainnetGenesisHash, simnetGenesisHash}},
 		HashMerkleRoot:       mainnetGenesisMerkleRoot,
 		AcceptedIDMerkleRoot: exampleAcceptedIDMerkleRoot,
 		UTXOCommitment:       exampleUTXOCommitment,

app/appmessage/p2p_msgblockheader.go

@@ -5,13 +5,12 @@
 package appmessage
 
 import (
-	"math"
+	"math/big"
 
 	"github.com/kaspanet/kaspad/domain/consensus/utils/consensushashing"
 
 	"github.com/kaspanet/kaspad/domain/consensus/model/externalapi"
 	"github.com/kaspanet/kaspad/util/mstime"
-	"github.com/pkg/errors"
 )
 
 // BaseBlockHeaderPayload is the base number of bytes a block header can be,
@@ -39,8 +38,8 @@ type MsgBlockHeader struct {
 	// Version of the block. This is not the same as the protocol version.
 	Version uint16
 
-	// Hashes of the parent block headers in the blockDAG.
-	ParentHashes []*externalapi.DomainHash
+	// Parents are the parent block hashes of the block in the DAG per superblock level.
+	Parents []externalapi.BlockLevelParents
 
 	// HashMerkleRoot is the merkle tree reference to hash of all transactions for the block.
 	HashMerkleRoot *externalapi.DomainHash
@@ -60,15 +59,16 @@ type MsgBlockHeader struct {
 
 	// Nonce used to generate the block.
 	Nonce uint64
-}
 
-// NumParentBlocks return the number of entries in ParentHashes
-func (h *MsgBlockHeader) NumParentBlocks() byte {
-	numParents := len(h.ParentHashes)
-	if numParents > math.MaxUint8 {
-		panic(errors.Errorf("number of parents is %d, which is more than one byte can fit", numParents))
-	}
-	return byte(numParents)
+	// DAASCore is the DAA score of the block.
+	DAAScore uint64
+
+	BlueScore uint64
+
+	// BlueWork is the blue work of the block.
+	BlueWork *big.Int
+
+	PruningPoint *externalapi.DomainHash
 }
 
 // BlockHash computes the block identifier hash for the given block header.
@@ -76,33 +76,27 @@ func (h *MsgBlockHeader) BlockHash() *externalapi.DomainHash {
 	return consensushashing.HeaderHash(BlockHeaderToDomainBlockHeader(h))
 }
 
-// IsGenesis returns true iff this block is a genesis block
-func (h *MsgBlockHeader) IsGenesis() bool {
-	return h.NumParentBlocks() == 0
-}
-
-// Command returns the protocol command string for the message. This is part
-// of the Message interface implementation.
-func (h *MsgBlockHeader) Command() MessageCommand {
-	return CmdHeader
-}
-
 // NewBlockHeader returns a new MsgBlockHeader using the provided version, previous
 // block hash, hash merkle root, accepted ID merkle root, difficulty bits, and nonce used to generate the
 // block with defaults or calclulated values for the remaining fields.
-func NewBlockHeader(version uint16, parentHashes []*externalapi.DomainHash, hashMerkleRoot *externalapi.DomainHash,
-	acceptedIDMerkleRoot *externalapi.DomainHash, utxoCommitment *externalapi.DomainHash, bits uint32, nonce uint64) *MsgBlockHeader {
+func NewBlockHeader(version uint16, parents []externalapi.BlockLevelParents, hashMerkleRoot *externalapi.DomainHash,
+	acceptedIDMerkleRoot *externalapi.DomainHash, utxoCommitment *externalapi.DomainHash, bits uint32, nonce,
+	daaScore, blueScore uint64, blueWork *big.Int, pruningPoint *externalapi.DomainHash) *MsgBlockHeader {
 
 	// Limit the timestamp to one millisecond precision since the protocol
 	// doesn't support better.
 	return &MsgBlockHeader{
 		Version:              version,
-		ParentHashes:         parentHashes,
+		Parents:              parents,
 		HashMerkleRoot:       hashMerkleRoot,
 		AcceptedIDMerkleRoot: acceptedIDMerkleRoot,
 		UTXOCommitment:       utxoCommitment,
 		Timestamp:            mstime.Now(),
 		Bits:                 bits,
 		Nonce:                nonce,
+		DAAScore:             daaScore,
+		BlueScore:            blueScore,
+		BlueWork:             blueWork,
+		PruningPoint:         pruningPoint,
 	}
 }

app/appmessage/p2p_msgblockheader_test.go

@@ -5,29 +5,34 @@
 package appmessage
 
 import (
+	"math/big"
 	"reflect"
 	"testing"
 
 	"github.com/davecgh/go-spew/spew"
 	"github.com/kaspanet/kaspad/domain/consensus/model/externalapi"
-	"github.com/kaspanet/kaspad/util/mstime"
 )
 
 // TestBlockHeader tests the MsgBlockHeader API.
 func TestBlockHeader(t *testing.T) {
 	nonce := uint64(0xba4d87a69924a93d)
 
-	hashes := []*externalapi.DomainHash{mainnetGenesisHash, simnetGenesisHash}
+	parents := []externalapi.BlockLevelParents{[]*externalapi.DomainHash{mainnetGenesisHash, simnetGenesisHash}}
 
 	merkleHash := mainnetGenesisMerkleRoot
 	acceptedIDMerkleRoot := exampleAcceptedIDMerkleRoot
 	bits := uint32(0x1d00ffff)
-	bh := NewBlockHeader(1, hashes, merkleHash, acceptedIDMerkleRoot, exampleUTXOCommitment, bits, nonce)
+	daaScore := uint64(123)
+	blueScore := uint64(456)
+	blueWork := big.NewInt(789)
+	pruningPoint := simnetGenesisHash
+	bh := NewBlockHeader(1, parents, merkleHash, acceptedIDMerkleRoot, exampleUTXOCommitment, bits, nonce,
+		daaScore, blueScore, blueWork, pruningPoint)
 
 	// Ensure we get the same data back out.
-	if !reflect.DeepEqual(bh.ParentHashes, hashes) {
-		t.Errorf("NewBlockHeader: wrong prev hashes - got %v, want %v",
-			spew.Sprint(bh.ParentHashes), spew.Sprint(hashes))
+	if !reflect.DeepEqual(bh.Parents, parents) {
+		t.Errorf("NewBlockHeader: wrong parents - got %v, want %v",
+			spew.Sprint(bh.Parents), spew.Sprint(parents))
 	}
 	if bh.HashMerkleRoot != merkleHash {
 		t.Errorf("NewBlockHeader: wrong merkle root - got %v, want %v",
@@ -41,44 +46,20 @@ func TestBlockHeader(t *testing.T) {
 		t.Errorf("NewBlockHeader: wrong nonce - got %v, want %v",
 			bh.Nonce, nonce)
 	}
-}
-
-func TestIsGenesis(t *testing.T) {
-	nonce := uint64(123123) // 0x1e0f3
-	bits := uint32(0x1d00ffff)
-	timestamp := mstime.UnixMilliseconds(0x495fab29000)
-
-	baseBlockHdr := &MsgBlockHeader{
-		Version:        1,
-		ParentHashes:   []*externalapi.DomainHash{mainnetGenesisHash, simnetGenesisHash},
-		HashMerkleRoot: mainnetGenesisMerkleRoot,
-		Timestamp:      timestamp,
-		Bits:           bits,
-		Nonce:          nonce,
+	if bh.DAAScore != daaScore {
+		t.Errorf("NewBlockHeader: wrong daaScore - got %v, want %v",
+			bh.DAAScore, daaScore)
 	}
-	genesisBlockHdr := &MsgBlockHeader{
-		Version:        1,
-		ParentHashes:   []*externalapi.DomainHash{},
-		HashMerkleRoot: mainnetGenesisMerkleRoot,
-		Timestamp:      timestamp,
-		Bits:           bits,
-		Nonce:          nonce,
+	if bh.BlueScore != blueScore {
+		t.Errorf("NewBlockHeader: wrong blueScore - got %v, want %v",
+			bh.BlueScore, blueScore)
 	}
-
-	tests := []struct {
-		in        *MsgBlockHeader // Block header to encode
-		isGenesis bool            // Expected result for call of .IsGenesis
-	}{
-		{genesisBlockHdr, true},
-		{baseBlockHdr, false},
+	if bh.BlueWork != blueWork {
+		t.Errorf("NewBlockHeader: wrong blueWork - got %v, want %v",
+			bh.BlueWork, blueWork)
 	}
-
-	t.Logf("Running %d tests", len(tests))
-	for i, test := range tests {
-		isGenesis := test.in.IsGenesis()
-		if isGenesis != test.isGenesis {
-			t.Errorf("MsgBlockHeader.IsGenesis: #%d got: %t, want: %t",
-				i, isGenesis, test.isGenesis)
-		}
+	if !bh.PruningPoint.Equal(pruningPoint) {
+		t.Errorf("NewBlockHeader: wrong pruningPoint - got %v, want %v",
+			bh.PruningPoint, pruningPoint)
 	}
 }

app/appmessage/p2p_msgblockwithtrusteddata.go

@@ -0,0 +1,54 @@
+package appmessage
+
+import (
+	"github.com/kaspanet/kaspad/domain/consensus/model/externalapi"
+	"math/big"
+)
+
+// MsgBlockWithTrustedData represents a kaspa BlockWithTrustedData message
+type MsgBlockWithTrustedData struct {
+	baseMessage
+
+	Block        *MsgBlock
+	DAAScore     uint64
+	DAAWindow    []*TrustedDataDataDAABlock
+	GHOSTDAGData []*BlockGHOSTDAGDataHashPair
+}
+
+// Command returns the protocol command string for the message
+func (msg *MsgBlockWithTrustedData) Command() MessageCommand {
+	return CmdBlockWithTrustedData
+}
+
+// NewMsgBlockWithTrustedData returns a new MsgBlockWithTrustedData.
+func NewMsgBlockWithTrustedData() *MsgBlockWithTrustedData {
+	return &MsgBlockWithTrustedData{}
+}
+
+// TrustedDataDataDAABlock is an appmessage representation of externalapi.TrustedDataDataDAABlock
+type TrustedDataDataDAABlock struct {
+	Block        *MsgBlock
+	GHOSTDAGData *BlockGHOSTDAGData
+}
+
+// BlockGHOSTDAGData is an appmessage representation of externalapi.BlockGHOSTDAGData
+type BlockGHOSTDAGData struct {
+	BlueScore          uint64
+	BlueWork           *big.Int
+	SelectedParent     *externalapi.DomainHash
+	MergeSetBlues      []*externalapi.DomainHash
+	MergeSetReds       []*externalapi.DomainHash
+	BluesAnticoneSizes []*BluesAnticoneSizes
+}
+
+// BluesAnticoneSizes is an appmessage representation of the BluesAnticoneSizes part of GHOSTDAG data.
+type BluesAnticoneSizes struct {
+	BlueHash     *externalapi.DomainHash
+	AnticoneSize externalapi.KType
+}
+
+// BlockGHOSTDAGDataHashPair is an appmessage representation of externalapi.BlockGHOSTDAGDataHashPair
+type BlockGHOSTDAGDataHashPair struct {
+	Hash         *externalapi.DomainHash
+	GHOSTDAGData *BlockGHOSTDAGData
+}

app/appmessage/p2p_msgblockwithtrusteddatav4.go

@@ -0,0 +1,20 @@
+package appmessage
+
+// MsgBlockWithTrustedDataV4 represents a kaspa BlockWithTrustedDataV4 message
+type MsgBlockWithTrustedDataV4 struct {
+	baseMessage
+
+	Block               *MsgBlock
+	DAAWindowIndices    []uint64
+	GHOSTDAGDataIndices []uint64
+}
+
+// Command returns the protocol command string for the message
+func (msg *MsgBlockWithTrustedDataV4) Command() MessageCommand {
+	return CmdBlockWithTrustedDataV4
+}
+
+// NewMsgBlockWithTrustedDataV4 returns a new MsgBlockWithTrustedDataV4.
+func NewMsgBlockWithTrustedDataV4() *MsgBlockWithTrustedDataV4 {
+	return &MsgBlockWithTrustedDataV4{}
+}

app/appmessage/p2p_msgdoneblockswithmetadata.go

@@ -0,0 +1,21 @@
+package appmessage
+
+// MsgDoneBlocksWithTrustedData implements the Message interface and represents a kaspa
+// DoneBlocksWithTrustedData message
+//
+// This message has no payload.
+type MsgDoneBlocksWithTrustedData struct {
+	baseMessage
+}
+
+// Command returns the protocol command string for the message. This is part
+// of the Message interface implementation.
+func (msg *MsgDoneBlocksWithTrustedData) Command() MessageCommand {
+	return CmdDoneBlocksWithTrustedData
+}
+
+// NewMsgDoneBlocksWithTrustedData returns a new kaspa DoneBlocksWithTrustedData message that conforms to the
+// Message interface.
+func NewMsgDoneBlocksWithTrustedData() *MsgDoneBlocksWithTrustedData {
+	return &MsgDoneBlocksWithTrustedData{}
+}

app/appmessage/p2p_msgdrequestpruningpointanditsanticoneheaders.go

@@ -0,0 +1,16 @@
+package appmessage
+
+// MsgRequestPruningPointAndItsAnticone represents a kaspa RequestPruningPointAndItsAnticone message
+type MsgRequestPruningPointAndItsAnticone struct {
+	baseMessage
+}
+
+// Command returns the protocol command string for the message
+func (msg *MsgRequestPruningPointAndItsAnticone) Command() MessageCommand {
+	return CmdRequestPruningPointAndItsAnticone
+}
+
+// NewMsgRequestPruningPointAndItsAnticone returns a new MsgRequestPruningPointAndItsAnticone.
+func NewMsgRequestPruningPointAndItsAnticone() *MsgRequestPruningPointAndItsAnticone {
+	return &MsgRequestPruningPointAndItsAnticone{}
+}

app/appmessage/p2p_msgibdblock_test.go

@@ -1,65 +0,0 @@
-// Copyright (c) 2013-2016 The btcsuite developers
-// Use of this source code is governed by an ISC
-// license that can be found in the LICENSE file.
-
-package appmessage
-
-import (
-	"reflect"
-	"testing"
-
-	"github.com/davecgh/go-spew/spew"
-)
-
-// TestIBDBlock tests the MsgIBDBlock API.
-func TestIBDBlock(t *testing.T) {
-	pver := ProtocolVersion
-
-	// Block 1 header.
-	parentHashes := blockOne.Header.ParentHashes
-	hashMerkleRoot := blockOne.Header.HashMerkleRoot
-	acceptedIDMerkleRoot := blockOne.Header.AcceptedIDMerkleRoot
-	utxoCommitment := blockOne.Header.UTXOCommitment
-	bits := blockOne.Header.Bits
-	nonce := blockOne.Header.Nonce
-	bh := NewBlockHeader(1, parentHashes, hashMerkleRoot, acceptedIDMerkleRoot, utxoCommitment, bits, nonce)
-
-	// Ensure the command is expected value.
-	wantCmd := MessageCommand(15)
-	msg := NewMsgIBDBlock(NewMsgBlock(bh))
-	if cmd := msg.Command(); cmd != wantCmd {
-		t.Errorf("NewMsgIBDBlock: wrong command - got %v want %v",
-			cmd, wantCmd)
-	}
-
-	// Ensure max payload is expected value for latest protocol version.
-	wantPayload := uint32(1024 * 1024 * 32)
-	maxPayload := msg.MaxPayloadLength(pver)
-	if maxPayload != wantPayload {
-		t.Errorf("MaxPayloadLength: wrong max payload length for "+
-			"protocol version %d - got %v, want %v", pver,
-			maxPayload, wantPayload)
-	}
-
-	// Ensure we get the same block header data back out.
-	if !reflect.DeepEqual(&msg.Header, bh) {
-		t.Errorf("NewMsgIBDBlock: wrong block header - got %v, want %v",
-			spew.Sdump(&msg.Header), spew.Sdump(bh))
-	}
-
-	// Ensure transactions are added properly.
-	tx := blockOne.Transactions[0].Copy()
-	msg.AddTransaction(tx)
-	if !reflect.DeepEqual(msg.Transactions, blockOne.Transactions) {
-		t.Errorf("AddTransaction: wrong transactions - got %v, want %v",
-			spew.Sdump(msg.Transactions),
-			spew.Sdump(blockOne.Transactions))
-	}
-
-	// Ensure transactions are properly cleared.
-	msg.ClearTransactions()
-	if len(msg.Transactions) != 0 {
-		t.Errorf("ClearTransactions: wrong transactions - got %v, want %v",
-			len(msg.Transactions), 0)
-	}
-}

app/appmessage/p2p_msgpruningpointhash.go

@@ -1,23 +0,0 @@
-package appmessage
-
-import (
-	"github.com/kaspanet/kaspad/domain/consensus/model/externalapi"
-)
-
-// MsgPruningPointHashMessage represents a kaspa PruningPointHash message
-type MsgPruningPointHashMessage struct {
-	baseMessage
-	Hash *externalapi.DomainHash
-}
-
-// Command returns the protocol command string for the message
-func (msg *MsgPruningPointHashMessage) Command() MessageCommand {
-	return CmdPruningPointHash
-}
-
-// NewPruningPointHashMessage returns a new kaspa PruningPointHash message
-func NewPruningPointHashMessage(hash *externalapi.DomainHash) *MsgPruningPointHashMessage {
-	return &MsgPruningPointHashMessage{
-		Hash: hash,
-	}
-}

app/appmessage/p2p_msgpruningpointproof.go

@@ -0,0 +1,20 @@
+package appmessage
+
+// MsgPruningPointProof represents a kaspa PruningPointProof message
+type MsgPruningPointProof struct {
+	baseMessage
+
+	Headers [][]*MsgBlockHeader
+}
+
+// Command returns the protocol command string for the message
+func (msg *MsgPruningPointProof) Command() MessageCommand {
+	return CmdPruningPointProof
+}
+
+// NewMsgPruningPointProof returns a new MsgPruningPointProof.
+func NewMsgPruningPointProof(headers [][]*MsgBlockHeader) *MsgPruningPointProof {
+	return &MsgPruningPointProof{
+		Headers: headers,
+	}
+}

app/appmessage/p2p_msgpruningpoints.go

@@ -0,0 +1,20 @@
+package appmessage
+
+// MsgPruningPoints represents a kaspa PruningPoints message
+type MsgPruningPoints struct {
+	baseMessage
+
+	Headers []*MsgBlockHeader
+}
+
+// Command returns the protocol command string for the message
+func (msg *MsgPruningPoints) Command() MessageCommand {
+	return CmdPruningPoints
+}
+
+// NewMsgPruningPoints returns a new MsgPruningPoints.
+func NewMsgPruningPoints(headers []*MsgBlockHeader) *MsgPruningPoints {
+	return &MsgPruningPoints{
+		Headers: headers,
+	}
+}

app/appmessage/p2p_msgrequestblocklocator.go

@@ -10,7 +10,6 @@ import (
 // The locator is returned via a locator message (MsgBlockLocator).
 type MsgRequestBlockLocator struct {
 	baseMessage
-	LowHash  *externalapi.DomainHash
 	HighHash *externalapi.DomainHash
 	Limit    uint32
 }
@@ -24,9 +23,8 @@ func (msg *MsgRequestBlockLocator) Command() MessageCommand {
 // NewMsgRequestBlockLocator returns a new RequestBlockLocator message that conforms to the
 // Message interface using the passed parameters and defaults for the remaining
 // fields.
-func NewMsgRequestBlockLocator(lowHash, highHash *externalapi.DomainHash, limit uint32) *MsgRequestBlockLocator {
+func NewMsgRequestBlockLocator(highHash *externalapi.DomainHash, limit uint32) *MsgRequestBlockLocator {
 	return &MsgRequestBlockLocator{
-		LowHash:  lowHash,
 		HighHash: highHash,
 		Limit:    limit,
 	}

app/appmessage/p2p_msgrequestblocklocator_test.go

@@ -16,7 +16,7 @@ func TestRequestBlockLocator(t *testing.T) {
 
 	// Ensure the command is expected value.
 	wantCmd := MessageCommand(9)
-	msg := NewMsgRequestBlockLocator(highHash, &externalapi.DomainHash{}, 0)
+	msg := NewMsgRequestBlockLocator(highHash, 0)
 	if cmd := msg.Command(); cmd != wantCmd {
 		t.Errorf("NewMsgRequestBlockLocator: wrong command - got %v want %v",
 			cmd, wantCmd)

app/appmessage/p2p_msgrequestheaders_test.go

@@ -10,7 +10,7 @@ import (
 	"github.com/kaspanet/kaspad/domain/consensus/model/externalapi"
 )
 
-// TestRequstIBDBlocks tests the MsgRequestHeaders API.
+// TestRequstIBDBlocks tests the MsgRequestIBDBlocks API.
 func TestRequstIBDBlocks(t *testing.T) {
 	hashStr := "000000000002e7ad7b9eef9479e4aabc65cb831269cc20d2632c13684406dee0"
 	lowHash, err := externalapi.NewDomainHashFromString(hashStr)
@@ -27,14 +27,14 @@ func TestRequstIBDBlocks(t *testing.T) {
 	// Ensure we get the same data back out.
 	msg := NewMsgRequstHeaders(lowHash, highHash)
 	if !msg.HighHash.Equal(highHash) {
-		t.Errorf("NewMsgRequstHeaders: wrong high hash - got %v, want %v",
+		t.Errorf("NewMsgRequstIBDBlocks: wrong high hash - got %v, want %v",
 			msg.HighHash, highHash)
 	}
 
 	// Ensure the command is expected value.
 	wantCmd := MessageCommand(4)
 	if cmd := msg.Command(); cmd != wantCmd {
-		t.Errorf("NewMsgRequstHeaders: wrong command - got %v want %v",
+		t.Errorf("NewMsgRequstIBDBlocks: wrong command - got %v want %v",
 			cmd, wantCmd)
 	}
 }

app/appmessage/p2p_msgrequestpruningpointproof.go

@@ -0,0 +1,16 @@
+package appmessage
+
+// MsgRequestPruningPointProof represents a kaspa RequestPruningPointProof message
+type MsgRequestPruningPointProof struct {
+	baseMessage
+}
+
+// Command returns the protocol command string for the message
+func (msg *MsgRequestPruningPointProof) Command() MessageCommand {
+	return CmdRequestPruningPointProof
+}
+
+// NewMsgRequestPruningPointProof returns a new MsgRequestPruningPointProof.
+func NewMsgRequestPruningPointProof() *MsgRequestPruningPointProof {
+	return &MsgRequestPruningPointProof{}
+}

app/appmessage/p2p_msgrequestpruningpointutxosetandblock.go

@@ -4,20 +4,20 @@ import (
 	"github.com/kaspanet/kaspad/domain/consensus/model/externalapi"
 )
 
-// MsgRequestPruningPointUTXOSetAndBlock represents a kaspa RequestPruningPointUTXOSetAndBlock message
-type MsgRequestPruningPointUTXOSetAndBlock struct {
+// MsgRequestPruningPointUTXOSet represents a kaspa RequestPruningPointUTXOSet message
+type MsgRequestPruningPointUTXOSet struct {
 	baseMessage
 	PruningPointHash *externalapi.DomainHash
 }
 
 // Command returns the protocol command string for the message
-func (msg *MsgRequestPruningPointUTXOSetAndBlock) Command() MessageCommand {
-	return CmdRequestPruningPointUTXOSetAndBlock
+func (msg *MsgRequestPruningPointUTXOSet) Command() MessageCommand {
+	return CmdRequestPruningPointUTXOSet
 }
 
-// NewMsgRequestPruningPointUTXOSetAndBlock returns a new MsgRequestPruningPointUTXOSetAndBlock
-func NewMsgRequestPruningPointUTXOSetAndBlock(pruningPointHash *externalapi.DomainHash) *MsgRequestPruningPointUTXOSetAndBlock {
-	return &MsgRequestPruningPointUTXOSetAndBlock{
+// NewMsgRequestPruningPointUTXOSet returns a new MsgRequestPruningPointUTXOSet
+func NewMsgRequestPruningPointUTXOSet(pruningPointHash *externalapi.DomainHash) *MsgRequestPruningPointUTXOSet {
+	return &MsgRequestPruningPointUTXOSet{
 		PruningPointHash: pruningPointHash,
 	}
 }

app/appmessage/p2p_msgtrusteddata.go

@@ -0,0 +1,25 @@
+package appmessage
+
+// MsgTrustedData represents a kaspa TrustedData message
+type MsgTrustedData struct {
+	baseMessage
+
+	DAAWindow    []*TrustedDataDAAHeader
+	GHOSTDAGData []*BlockGHOSTDAGDataHashPair
+}
+
+// Command returns the protocol command string for the message
+func (msg *MsgTrustedData) Command() MessageCommand {
+	return CmdTrustedData
+}
+
+// NewMsgTrustedData returns a new MsgTrustedData.
+func NewMsgTrustedData() *MsgTrustedData {
+	return &MsgTrustedData{}
+}
+
+// TrustedDataDAAHeader is an appmessage representation of externalapi.TrustedDataDataDAAHeader
+type TrustedDataDAAHeader struct {
+	Header       *MsgBlockHeader
+	GHOSTDAGData *BlockGHOSTDAGData
+}

app/appmessage/p2p_msgtx.go

@@ -90,16 +90,18 @@ type TxIn struct {
 	PreviousOutpoint Outpoint
 	SignatureScript  []byte
 	Sequence         uint64
+	SigOpCount       byte
 }
 
 // NewTxIn returns a new kaspa transaction input with the provided
 // previous outpoint point and signature script with a default sequence of
 // MaxTxInSequenceNum.
-func NewTxIn(prevOut *Outpoint, signatureScript []byte, sequence uint64) *TxIn {
+func NewTxIn(prevOut *Outpoint, signatureScript []byte, sequence uint64, sigOpCount byte) *TxIn {
 	return &TxIn{
 		PreviousOutpoint: *prevOut,
 		SignatureScript:  signatureScript,
 		Sequence:         sequence,
+		SigOpCount:       sigOpCount,
 	}
 }
 
@@ -206,6 +208,7 @@ func (msg *MsgTx) Copy() *MsgTx {
 			PreviousOutpoint: newOutpoint,
 			SignatureScript:  newScript,
 			Sequence:         oldTxIn.Sequence,
+			SigOpCount:       oldTxIn.SigOpCount,
 		}
 
 		// Finally, append this fully copied txin.

app/appmessage/p2p_msgtx_test.go

@@ -22,7 +22,7 @@ import (
 
 // TestTx tests the MsgTx API.
 func TestTx(t *testing.T) {
-	pver := ProtocolVersion
+	pver := uint32(4)
 
 	txIDStr := "000000000003ba27aa200b1cecaad478d2b00432346c3f1f3986da1afd33e506"
 	txID, err := transactionid.FromString(txIDStr)
@@ -68,7 +68,7 @@ func TestTx(t *testing.T) {
 
 	// Ensure we get the same transaction input back out.
 	sigScript := []byte{0x04, 0x31, 0xdc, 0x00, 0x1b, 0x01, 0x62}
-	txIn := NewTxIn(prevOut, sigScript, constants.MaxTxInSequenceNum)
+	txIn := NewTxIn(prevOut, sigScript, constants.MaxTxInSequenceNum, 1)
 	if !reflect.DeepEqual(&txIn.PreviousOutpoint, prevOut) {
 		t.Errorf("NewTxIn: wrong prev outpoint - got %v, want %v",
 			spew.Sprint(&txIn.PreviousOutpoint),

app/appmessage/p2p_msgversion.go

@@ -82,12 +82,12 @@ func (msg *MsgVersion) Command() MessageCommand {
 // Message interface using the passed parameters and defaults for the remaining
 // fields.
 func NewMsgVersion(addr *NetAddress, id *id.ID, network string,
-	subnetworkID *externalapi.DomainSubnetworkID) *MsgVersion {
+	subnetworkID *externalapi.DomainSubnetworkID, protocolVersion uint32) *MsgVersion {
 
 	// Limit the timestamp to one millisecond precision since the protocol
 	// doesn't support better.
 	return &MsgVersion{
-		ProtocolVersion: ProtocolVersion,
+		ProtocolVersion: protocolVersion,
 		Network:         network,
 		Services:        0,
 		Timestamp:       mstime.Now(),

app/appmessage/p2p_msgversion_test.go

@@ -15,7 +15,7 @@ import (
 
 // TestVersion tests the MsgVersion API.
 func TestVersion(t *testing.T) {
-	pver := ProtocolVersion
+	pver := uint32(4)
 
 	// Create version message data.
 	tcpAddrMe := &net.TCPAddr{IP: net.ParseIP("127.0.0.1"), Port: 16111}
@@ -26,7 +26,7 @@ func TestVersion(t *testing.T) {
 	}
 
 	// Ensure we get the correct data back out.
-	msg := NewMsgVersion(me, generatedID, "mainnet", nil)
+	msg := NewMsgVersion(me, generatedID, "mainnet", nil, 4)
 	if msg.ProtocolVersion != pver {
 		t.Errorf("NewMsgVersion: wrong protocol version - got %v, want %v",
 			msg.ProtocolVersion, pver)

app/appmessage/p2p_netaddress.go

@@ -5,8 +5,9 @@
 package appmessage
 
 import (
-	"github.com/kaspanet/kaspad/util/mstime"
 	"net"
+
+	"github.com/kaspanet/kaspad/util/mstime"
 )
 
 // NetAddress defines information about a peer on the network including the time
@@ -57,3 +58,7 @@ func NewNetAddressTimestamp(
 func NewNetAddress(addr *net.TCPAddr) *NetAddress {
 	return NewNetAddressIPPort(addr.IP, uint16(addr.Port))
 }
+
+func (na NetAddress) String() string {
+	return na.TCPAddress().String()
+}

app/appmessage/p2p_ready.go

@@ -0,0 +1,22 @@
+package appmessage
+
+// MsgReady implements the Message interface and represents a kaspa
+// Ready message. It is used to notify that the peer is ready to receive
+// messages.
+//
+// This message has no payload.
+type MsgReady struct {
+	baseMessage
+}
+
+// Command returns the protocol command string for the message. This is part
+// of the Message interface implementation.
+func (msg *MsgReady) Command() MessageCommand {
+	return CmdReady
+}
+
+// NewMsgReady returns a new kaspa Ready message that conforms to the
+// Message interface.
+func NewMsgReady() *MsgReady {
+	return &MsgReady{}
+}

app/appmessage/p2p_requestpruningpointhash.go

@@ -1,16 +0,0 @@
-package appmessage
-
-// MsgRequestPruningPointHashMessage represents a kaspa RequestPruningPointHashMessage message
-type MsgRequestPruningPointHashMessage struct {
-	baseMessage
-}
-
-// Command returns the protocol command string for the message
-func (msg *MsgRequestPruningPointHashMessage) Command() MessageCommand {
-	return CmdRequestPruningPointHash
-}
-
-// NewMsgRequestPruningPointHashMessage returns a new kaspa RequestPruningPointHash message
-func NewMsgRequestPruningPointHashMessage() *MsgRequestPruningPointHashMessage {
-	return &MsgRequestPruningPointHashMessage{}
-}

app/appmessage/protocol.go

@@ -11,9 +11,6 @@ import (
 )
 
 const (
-	// ProtocolVersion is the latest protocol version this package supports.
-	ProtocolVersion uint32 = 1
-
 	// DefaultServices describes the default services that are supported by
 	// the server.
 	DefaultServices = SFNodeNetwork | SFNodeBloom | SFNodeCF

app/appmessage/rpc_estimate_network_hashes_per_second.go

@@ -0,0 +1,43 @@
+package appmessage
+
+// EstimateNetworkHashesPerSecondRequestMessage is an appmessage corresponding to
+// its respective RPC message
+type EstimateNetworkHashesPerSecondRequestMessage struct {
+	baseMessage
+	StartHash  string
+	WindowSize uint32
+}
+
+// Command returns the protocol command string for the message
+func (msg *EstimateNetworkHashesPerSecondRequestMessage) Command() MessageCommand {
+	return CmdEstimateNetworkHashesPerSecondRequestMessage
+}
+
+// NewEstimateNetworkHashesPerSecondRequestMessage returns a instance of the message
+func NewEstimateNetworkHashesPerSecondRequestMessage(startHash string, windowSize uint32) *EstimateNetworkHashesPerSecondRequestMessage {
+	return &EstimateNetworkHashesPerSecondRequestMessage{
+		StartHash:  startHash,
+		WindowSize: windowSize,
+	}
+}
+
+// EstimateNetworkHashesPerSecondResponseMessage is an appmessage corresponding to
+// its respective RPC message
+type EstimateNetworkHashesPerSecondResponseMessage struct {
+	baseMessage
+	NetworkHashesPerSecond uint64
+
+	Error *RPCError
+}
+
+// Command returns the protocol command string for the message
+func (msg *EstimateNetworkHashesPerSecondResponseMessage) Command() MessageCommand {
+	return CmdEstimateNetworkHashesPerSecondResponseMessage
+}
+
+// NewEstimateNetworkHashesPerSecondResponseMessage returns a instance of the message
+func NewEstimateNetworkHashesPerSecondResponseMessage(networkHashesPerSecond uint64) *EstimateNetworkHashesPerSecondResponseMessage {
+	return &EstimateNetworkHashesPerSecondResponseMessage{
+		NetworkHashesPerSecond: networkHashesPerSecond,
+	}
+}

app/appmessage/rpc_get_balance_by_address.go

@@ -0,0 +1,41 @@
+package appmessage
+
+// GetBalanceByAddressRequestMessage is an appmessage corresponding to
+// its respective RPC message
+type GetBalanceByAddressRequestMessage struct {
+	baseMessage
+	Address string
+}
+
+// Command returns the protocol command string for the message
+func (msg *GetBalanceByAddressRequestMessage) Command() MessageCommand {
+	return CmdGetBalanceByAddressRequestMessage
+}
+
+// NewGetBalanceByAddressRequest returns a instance of the message
+func NewGetBalanceByAddressRequest(address string) *GetBalanceByAddressRequestMessage {
+	return &GetBalanceByAddressRequestMessage{
+		Address: address,
+	}
+}
+
+// GetBalanceByAddressResponseMessage is an appmessage corresponding to
+// its respective RPC message
+type GetBalanceByAddressResponseMessage struct {
+	baseMessage
+	Balance uint64
+
+	Error *RPCError
+}
+
+// Command returns the protocol command string for the message
+func (msg *GetBalanceByAddressResponseMessage) Command() MessageCommand {
+	return CmdGetBalanceByAddressResponseMessage
+}
+
+// NewGetBalanceByAddressResponse returns an instance of the message
+func NewGetBalanceByAddressResponse(Balance uint64) *GetBalanceByAddressResponseMessage {
+	return &GetBalanceByAddressResponseMessage{
+		Balance: Balance,
+	}
+}

app/appmessage/rpc_get_balances_by_addresses.go

@@ -0,0 +1,47 @@
+package appmessage
+
+// GetBalancesByAddressesRequestMessage is an appmessage corresponding to
+// its respective RPC message
+type GetBalancesByAddressesRequestMessage struct {
+	baseMessage
+	Addresses []string
+}
+
+// Command returns the protocol command string for the message
+func (msg *GetBalancesByAddressesRequestMessage) Command() MessageCommand {
+	return CmdGetBalancesByAddressesRequestMessage
+}
+
+// NewGetBalancesByAddressesRequest returns a instance of the message
+func NewGetBalancesByAddressesRequest(addresses []string) *GetBalancesByAddressesRequestMessage {
+	return &GetBalancesByAddressesRequestMessage{
+		Addresses: addresses,
+	}
+}
+
+// BalancesByAddressesEntry represents the balance of some address
+type BalancesByAddressesEntry struct {
+	Address string
+	Balance uint64
+}
+
+// GetBalancesByAddressesResponseMessage is an appmessage corresponding to
+// its respective RPC message
+type GetBalancesByAddressesResponseMessage struct {
+	baseMessage
+	Entries []*BalancesByAddressesEntry
+
+	Error *RPCError
+}
+
+// Command returns the protocol command string for the message
+func (msg *GetBalancesByAddressesResponseMessage) Command() MessageCommand {
+	return CmdGetBalancesByAddressesResponseMessage
+}
+
+// NewGetBalancesByAddressesResponse returns an instance of the message
+func NewGetBalancesByAddressesResponse(entries []*BalancesByAddressesEntry) *GetBalancesByAddressesResponseMessage {
+	return &GetBalancesByAddressesResponseMessage{
+		Entries: entries,
+	}
+}

app/appmessage/rpc_get_block.go

@@ -4,8 +4,8 @@ package appmessage
 // its respective RPC message
 type GetBlockRequestMessage struct {
 	baseMessage
-	Hash                          string
-	IncludeTransactionVerboseData bool
+	Hash                string
+	IncludeTransactions bool
 }
 
 // Command returns the protocol command string for the message
@@ -14,10 +14,10 @@ func (msg *GetBlockRequestMessage) Command() MessageCommand {
 }
 
 // NewGetBlockRequestMessage returns a instance of the message
-func NewGetBlockRequestMessage(hash string, includeTransactionVerboseData bool) *GetBlockRequestMessage {
+func NewGetBlockRequestMessage(hash string, includeTransactions bool) *GetBlockRequestMessage {
 	return &GetBlockRequestMessage{
-		Hash:                          hash,
-		IncludeTransactionVerboseData: includeTransactionVerboseData,
+		Hash:                hash,
+		IncludeTransactions: includeTransactions,
 	}
 }
 

app/appmessage/rpc_get_block_dag_info.go

@@ -28,6 +28,7 @@ type GetBlockDAGInfoResponseMessage struct {
 	Difficulty          float64
 	PastMedianTime      int64
 	PruningPointHash    string
+	VirtualDAAScore     uint64
 
 	Error *RPCError
 }

app/appmessage/rpc_get_blocks.go

@@ -4,9 +4,9 @@ package appmessage
 // its respective RPC message
 type GetBlocksRequestMessage struct {
 	baseMessage
-	LowHash                       string
-	IncludeBlocks                 bool
-	IncludeTransactionVerboseData bool
+	LowHash             string
+	IncludeBlocks       bool
+	IncludeTransactions bool
 }
 
 // Command returns the protocol command string for the message
@@ -16,11 +16,11 @@ func (msg *GetBlocksRequestMessage) Command() MessageCommand {
 
 // NewGetBlocksRequestMessage returns a instance of the message
 func NewGetBlocksRequestMessage(lowHash string, includeBlocks bool,
-	includeTransactionVerboseData bool) *GetBlocksRequestMessage {
+	includeTransactions bool) *GetBlocksRequestMessage {
 	return &GetBlocksRequestMessage{
-		LowHash:                       lowHash,
-		IncludeBlocks:                 includeBlocks,
-		IncludeTransactionVerboseData: includeTransactionVerboseData,
+		LowHash:             lowHash,
+		IncludeBlocks:       includeBlocks,
+		IncludeTransactions: includeTransactions,
 	}
 }
 

app/appmessage/rpc_get_info.go

@@ -20,8 +20,9 @@ func NewGetInfoRequestMessage() *GetInfoRequestMessage {
 // its respective RPC message
 type GetInfoResponseMessage struct {
 	baseMessage
-	P2PID       string
-	MempoolSize uint64
+	P2PID         string
+	MempoolSize   uint64
+	ServerVersion string
 
 	Error *RPCError
 }
@@ -32,9 +33,10 @@ func (msg *GetInfoResponseMessage) Command() MessageCommand {
 }
 
 // NewGetInfoResponseMessage returns a instance of the message
-func NewGetInfoResponseMessage(p2pID string, mempoolSize uint64) *GetInfoResponseMessage {
+func NewGetInfoResponseMessage(p2pID string, mempoolSize uint64, serverVersion string) *GetInfoResponseMessage {
 	return &GetInfoResponseMessage{
-		P2PID:       p2pID,
-		MempoolSize: mempoolSize,
+		P2PID:         p2pID,
+		MempoolSize:   mempoolSize,
+		ServerVersion: serverVersion,
 	}
 }

app/appmessage/rpc_get_virtual_selected_parent_chain_from_block.go

@@ -24,7 +24,7 @@ func NewGetVirtualSelectedParentChainFromBlockRequestMessage(startHash string) *
 type GetVirtualSelectedParentChainFromBlockResponseMessage struct {
 	baseMessage
 	RemovedChainBlockHashes []string
-	AddedChainBlocks        []*ChainBlock
+	AddedChainBlockHashes   []string
 
 	Error *RPCError
 }
@@ -35,11 +35,11 @@ func (msg *GetVirtualSelectedParentChainFromBlockResponseMessage) Command() Mess
 }
 
 // NewGetVirtualSelectedParentChainFromBlockResponseMessage returns a instance of the message
-func NewGetVirtualSelectedParentChainFromBlockResponseMessage(removedChainBlockHashes []string,
-	addedChainBlocks []*ChainBlock) *GetVirtualSelectedParentChainFromBlockResponseMessage {
+func NewGetVirtualSelectedParentChainFromBlockResponseMessage(removedChainBlockHashes,
+	addedChainBlockHashes []string) *GetVirtualSelectedParentChainFromBlockResponseMessage {
 
 	return &GetVirtualSelectedParentChainFromBlockResponseMessage{
 		RemovedChainBlockHashes: removedChainBlockHashes,
-		AddedChainBlocks:        addedChainBlocks,
+		AddedChainBlockHashes:   addedChainBlockHashes,
 	}
 }

app/appmessage/rpc_notify_virtual_daa_score_changed.go

@@ -0,0 +1,55 @@
+package appmessage
+
+// NotifyVirtualDaaScoreChangedRequestMessage is an appmessage corresponding to
+// its respective RPC message
+type NotifyVirtualDaaScoreChangedRequestMessage struct {
+	baseMessage
+}
+
+// Command returns the protocol command string for the message
+func (msg *NotifyVirtualDaaScoreChangedRequestMessage) Command() MessageCommand {
+	return CmdNotifyVirtualDaaScoreChangedRequestMessage
+}
+
+// NewNotifyVirtualDaaScoreChangedRequestMessage returns a instance of the message
+func NewNotifyVirtualDaaScoreChangedRequestMessage() *NotifyVirtualDaaScoreChangedRequestMessage {
+	return &NotifyVirtualDaaScoreChangedRequestMessage{}
+}
+
+// NotifyVirtualDaaScoreChangedResponseMessage is an appmessage corresponding to
+// its respective RPC message
+type NotifyVirtualDaaScoreChangedResponseMessage struct {
+	baseMessage
+	Error *RPCError
+}
+
+// Command returns the protocol command string for the message
+func (msg *NotifyVirtualDaaScoreChangedResponseMessage) Command() MessageCommand {
+	return CmdNotifyVirtualDaaScoreChangedResponseMessage
+}
+
+// NewNotifyVirtualDaaScoreChangedResponseMessage returns a instance of the message
+func NewNotifyVirtualDaaScoreChangedResponseMessage() *NotifyVirtualDaaScoreChangedResponseMessage {
+	return &NotifyVirtualDaaScoreChangedResponseMessage{}
+}
+
+// VirtualDaaScoreChangedNotificationMessage is an appmessage corresponding to
+// its respective RPC message
+type VirtualDaaScoreChangedNotificationMessage struct {
+	baseMessage
+	VirtualDaaScore uint64
+}
+
+// Command returns the protocol command string for the message
+func (msg *VirtualDaaScoreChangedNotificationMessage) Command() MessageCommand {
+	return CmdVirtualDaaScoreChangedNotificationMessage
+}
+
+// NewVirtualDaaScoreChangedNotificationMessage returns a instance of the message
+func NewVirtualDaaScoreChangedNotificationMessage(
+	virtualDaaScore uint64) *VirtualDaaScoreChangedNotificationMessage {
+
+	return &VirtualDaaScoreChangedNotificationMessage{
+		VirtualDaaScore: virtualDaaScore,
+	}
+}

app/appmessage/rpc_notify_virtual_selected_parent_chain_changed.go

@@ -38,19 +38,7 @@ func NewNotifyVirtualSelectedParentChainChangedResponseMessage() *NotifyVirtualS
 type VirtualSelectedParentChainChangedNotificationMessage struct {
 	baseMessage
 	RemovedChainBlockHashes []string
-	AddedChainBlocks        []*ChainBlock
-}
-
-// ChainBlock represents a DAG chain-block
-type ChainBlock struct {
-	Hash           string
-	AcceptedBlocks []*AcceptedBlock
-}
-
-// AcceptedBlock represents a block accepted into the DAG
-type AcceptedBlock struct {
-	Hash                   string
-	AcceptedTransactionIDs []string
+	AddedChainBlockHashes   []string
 }
 
 // Command returns the protocol command string for the message
@@ -59,11 +47,11 @@ func (msg *VirtualSelectedParentChainChangedNotificationMessage) Command() Messa
 }
 
 // NewVirtualSelectedParentChainChangedNotificationMessage returns a instance of the message
-func NewVirtualSelectedParentChainChangedNotificationMessage(removedChainBlockHashes []string,
-	addedChainBlocks []*ChainBlock) *VirtualSelectedParentChainChangedNotificationMessage {
+func NewVirtualSelectedParentChainChangedNotificationMessage(removedChainBlockHashes,
+	addedChainBlocks []string) *VirtualSelectedParentChainChangedNotificationMessage {
 
 	return &VirtualSelectedParentChainChangedNotificationMessage{
 		RemovedChainBlockHashes: removedChainBlockHashes,
-		AddedChainBlocks:        addedChainBlocks,
+		AddedChainBlockHashes:   addedChainBlocks,
 	}
 }

app/appmessage/rpc_submit_block.go

@@ -4,7 +4,8 @@ package appmessage
 // its respective RPC message
 type SubmitBlockRequestMessage struct {
 	baseMessage
-	Block *RPCBlock
+	Block             *RPCBlock
+	AllowNonDAABlocks bool
 }
 
 // Command returns the protocol command string for the message
@@ -13,9 +14,10 @@ func (msg *SubmitBlockRequestMessage) Command() MessageCommand {
 }
 
 // NewSubmitBlockRequestMessage returns a instance of the message
-func NewSubmitBlockRequestMessage(block *RPCBlock) *SubmitBlockRequestMessage {
+func NewSubmitBlockRequestMessage(block *RPCBlock, allowNonDAABlocks bool) *SubmitBlockRequestMessage {
 	return &SubmitBlockRequestMessage{
-		Block: block,
+		Block:             block,
+		AllowNonDAABlocks: allowNonDAABlocks,
 	}
 }
 
@@ -53,7 +55,7 @@ func (msg *SubmitBlockResponseMessage) Command() MessageCommand {
 	return CmdSubmitBlockResponseMessage
 }
 
-// NewSubmitBlockResponseMessage returns a instance of the message
+// NewSubmitBlockResponseMessage returns an instance of the message
 func NewSubmitBlockResponseMessage() *SubmitBlockResponseMessage {
 	return &SubmitBlockResponseMessage{}
 }
@@ -70,22 +72,34 @@ type RPCBlock struct {
 // used over RPC
 type RPCBlockHeader struct {
 	Version              uint32
-	ParentHashes         []string
+	Parents              []*RPCBlockLevelParents
 	HashMerkleRoot       string
 	AcceptedIDMerkleRoot string
 	UTXOCommitment       string
 	Timestamp            int64
 	Bits                 uint32
 	Nonce                uint64
+	DAAScore             uint64
+	BlueScore            uint64
+	BlueWork             string
+	PruningPoint         string
+}
+
+// RPCBlockLevelParents holds parent hashes for one block level
+type RPCBlockLevelParents struct {
+	ParentHashes []string
 }
 
 // RPCBlockVerboseData holds verbose data about a block
 type RPCBlockVerboseData struct {
-	Hash               string
-	Difficulty         float64
-	SelectedParentHash string
-	TransactionIDs     []string
-	IsHeaderOnly       bool
-	BlueScore          uint64
-	ChildrenHashes     []string
+	Hash                string
+	Difficulty          float64
+	SelectedParentHash  string
+	TransactionIDs      []string
+	IsHeaderOnly        bool
+	BlueScore           uint64
+	ChildrenHashes      []string
+	MergeSetBluesHashes []string
+	MergeSetRedsHashes  []string
+	IsChainBlock        bool
 }

app/appmessage/rpc_submit_transaction.go

@@ -5,6 +5,7 @@ package appmessage
 type SubmitTransactionRequestMessage struct {
 	baseMessage
 	Transaction *RPCTransaction
+	AllowOrphan bool
 }
 
 // Command returns the protocol command string for the message
@@ -13,9 +14,10 @@ func (msg *SubmitTransactionRequestMessage) Command() MessageCommand {
 }
 
 // NewSubmitTransactionRequestMessage returns a instance of the message
-func NewSubmitTransactionRequestMessage(transaction *RPCTransaction) *SubmitTransactionRequestMessage {
+func NewSubmitTransactionRequestMessage(transaction *RPCTransaction, allowOrphan bool) *SubmitTransactionRequestMessage {
 	return &SubmitTransactionRequestMessage{
 		Transaction: transaction,
+		AllowOrphan: allowOrphan,
 	}
 }
 
@@ -59,6 +61,7 @@ type RPCTransactionInput struct {
 	PreviousOutpoint *RPCOutpoint
 	SignatureScript  string
 	Sequence         uint64
+	SigOpCount       byte
 	VerboseData      *RPCTransactionInputVerboseData
 }
 
@@ -96,7 +99,7 @@ type RPCUTXOEntry struct {
 type RPCTransactionVerboseData struct {
 	TransactionID string
 	Hash          string
-	Size          uint64
+	Mass          uint64
 	BlockHash     string
 	BlockTime     uint64
 }

app/component_manager.go

@@ -4,7 +4,8 @@ import (
 	"fmt"
 	"sync/atomic"
 
-	"github.com/kaspanet/kaspad/app/appmessage"
+	"github.com/kaspanet/kaspad/domain/miningmanager/mempool"
+
 	"github.com/kaspanet/kaspad/app/protocol"
 	"github.com/kaspanet/kaspad/app/rpc"
 	"github.com/kaspanet/kaspad/domain"
@@ -14,7 +15,6 @@ import (
 	infrastructuredatabase "github.com/kaspanet/kaspad/infrastructure/db/database"
 	"github.com/kaspanet/kaspad/infrastructure/network/addressmanager"
 	"github.com/kaspanet/kaspad/infrastructure/network/connmanager"
-	"github.com/kaspanet/kaspad/infrastructure/network/dnsseed"
 	"github.com/kaspanet/kaspad/infrastructure/network/netadapter"
 	"github.com/kaspanet/kaspad/infrastructure/network/netadapter/id"
 	"github.com/kaspanet/kaspad/util/panics"
@@ -46,8 +46,6 @@ func (a *ComponentManager) Start() {
 		panics.Exit(log, fmt.Sprintf("Error starting the net adapter: %+v", err))
 	}
 
-	a.maybeSeedFromDNS()
-
 	a.connectionManager.Start()
 }
 
@@ -83,8 +81,11 @@ func NewComponentManager(cfg *config.Config, db infrastructuredatabase.Database,
 		IsArchival:                      cfg.IsArchivalNode,
 		EnableSanityCheckPruningUTXOSet: cfg.EnableSanityCheckPruningUTXOSet,
 	}
+	mempoolConfig := mempool.DefaultConfig(&consensusConfig.Params)
+	mempoolConfig.MaximumOrphanTransactionCount = cfg.MaxOrphanTxs
+	mempoolConfig.MinimumRelayTransactionFee = cfg.MinRelayTxFee
 
-	domain, err := domain.New(&consensusConfig, db)
+	domain, err := domain.New(&consensusConfig, mempoolConfig, db)
 	if err != nil {
 		return nil, err
 	}
@@ -101,7 +102,7 @@ func NewComponentManager(cfg *config.Config, db infrastructuredatabase.Database,
 
 	var utxoIndex *utxoindex.UTXOIndex
 	if cfg.UTXOIndex {
-		utxoIndex, err = utxoindex.New(domain.Consensus(), db)
+		utxoIndex, err = utxoindex.New(domain, db)
 		if err != nil {
 			return nil, err
 		}
@@ -151,29 +152,13 @@ func setupRPC(
 		utxoIndex,
 		shutDownChan,
 	)
+	protocolManager.SetOnVirtualChange(rpcManager.NotifyVirtualChange)
 	protocolManager.SetOnBlockAddedToDAGHandler(rpcManager.NotifyBlockAddedToDAG)
 	protocolManager.SetOnPruningPointUTXOSetOverrideHandler(rpcManager.NotifyPruningPointUTXOSetOverride)
 
 	return rpcManager
 }
 
-func (a *ComponentManager) maybeSeedFromDNS() {
-	if !a.cfg.DisableDNSSeed {
-		dnsseed.SeedFromDNS(a.cfg.NetParams(), a.cfg.DNSSeed, false, nil,
-			a.cfg.Lookup, func(addresses []*appmessage.NetAddress) {
-				// Kaspad uses a lookup of the dns seeder here. Since seeder returns
-				// IPs of nodes and not its own IP, we can not know real IP of
-				// source. So we'll take first returned address as source.
-				a.addressManager.AddAddresses(addresses...)
-			})
-
-		dnsseed.SeedFromGRPC(a.cfg.NetParams(), a.cfg.GRPCSeed, false, nil,
-			func(addresses []*appmessage.NetAddress) {
-				a.addressManager.AddAddresses(addresses...)
-			})
-	}
-}
-
 // P2PNodeID returns the network ID associated with this ComponentManager
 func (a *ComponentManager) P2PNodeID() *id.ID {
 	return a.netAdapter.ID()

app/protocol/common/common.go

@@ -1,6 +1,8 @@
 package common
 
 import (
+	peerpkg "github.com/kaspanet/kaspad/app/protocol/peer"
+	routerpkg "github.com/kaspanet/kaspad/infrastructure/network/netadapter/router"
 	"time"
 
 	"github.com/pkg/errors"
@@ -8,7 +10,18 @@ import (
 
 // DefaultTimeout is the default duration to wait for enqueuing/dequeuing
 // to/from routes.
-const DefaultTimeout = 30 * time.Second
+const DefaultTimeout = 120 * time.Second
 
 // ErrPeerWithSameIDExists signifies that a peer with the same ID already exist.
 var ErrPeerWithSameIDExists = errors.New("ready peer with the same ID already exists")
+
+type flowExecuteFunc func(peer *peerpkg.Peer)
+
+// Flow is a a data structure that is used in order to associate a p2p flow to some route in a router.
+type Flow struct {
+	Name        string
+	ExecuteFunc flowExecuteFunc
+}
+
+// FlowInitializeFunc is a function that is used in order to initialize a flow
+type FlowInitializeFunc func(route *routerpkg.Route, peer *peerpkg.Peer) error

app/protocol/flowcontext/blocks.go

@@ -1,23 +1,23 @@
 package flowcontext
 
 import (
+	"time"
+
 	peerpkg "github.com/kaspanet/kaspad/app/protocol/peer"
 	"github.com/kaspanet/kaspad/app/protocol/protocolerrors"
+	"github.com/kaspanet/kaspad/domain/consensus/model/externalapi"
 	"github.com/kaspanet/kaspad/domain/consensus/ruleerrors"
+	"github.com/kaspanet/kaspad/domain/consensus/utils/consensushashing"
 	"github.com/pkg/errors"
 
-	"github.com/kaspanet/kaspad/domain/consensus/model/externalapi"
-	"github.com/kaspanet/kaspad/domain/consensus/utils/consensushashing"
-
 	"github.com/kaspanet/kaspad/app/appmessage"
-	"github.com/kaspanet/kaspad/app/protocol/flows/blockrelay"
 )
 
 // OnNewBlock updates the mempool after a new block arrival, and
 // relays newly unorphaned transactions and possibly rebroadcast
 // manually added transactions when not in IBD.
 func (f *FlowContext) OnNewBlock(block *externalapi.DomainBlock,
-	blockInsertionResult *externalapi.BlockInsertionResult) error {
+	virtualChangeSet *externalapi.VirtualChangeSet) error {
 
 	hash := consensushashing.BlockHash(block)
 	log.Debugf("OnNewBlock start for block %s", hash)
@@ -31,10 +31,10 @@ func (f *FlowContext) OnNewBlock(block *externalapi.DomainBlock,
 	log.Debugf("OnNewBlock: block %s unorphaned %d blocks", hash, len(unorphaningResults))
 
 	newBlocks := []*externalapi.DomainBlock{block}
-	newBlockInsertionResults := []*externalapi.BlockInsertionResult{blockInsertionResult}
+	newVirtualChangeSets := []*externalapi.VirtualChangeSet{virtualChangeSet}
 	for _, unorphaningResult := range unorphaningResults {
 		newBlocks = append(newBlocks, unorphaningResult.block)
-		newBlockInsertionResults = append(newBlockInsertionResults, unorphaningResult.blockInsertionResult)
+		newVirtualChangeSets = append(newVirtualChangeSets, unorphaningResult.virtualChangeSet)
 	}
 
 	allAcceptedTransactions := make([]*externalapi.DomainTransaction, 0)
@@ -48,8 +48,8 @@ func (f *FlowContext) OnNewBlock(block *externalapi.DomainBlock,
 
 		if f.onBlockAddedToDAGHandler != nil {
 			log.Debugf("OnNewBlock: calling f.onBlockAddedToDAGHandler for block %s", hash)
-			blockInsertionResult = newBlockInsertionResults[i]
-			err := f.onBlockAddedToDAGHandler(newBlock, blockInsertionResult)
+			virtualChangeSet = newVirtualChangeSets[i]
+			err := f.onBlockAddedToDAGHandler(newBlock, virtualChangeSet)
 			if err != nil {
 				return err
 			}
@@ -59,6 +59,15 @@ func (f *FlowContext) OnNewBlock(block *externalapi.DomainBlock,
 	return f.broadcastTransactionsAfterBlockAdded(newBlocks, allAcceptedTransactions)
 }
 
+// OnVirtualChange calls the handler function whenever the virtual block changes.
+func (f *FlowContext) OnVirtualChange(virtualChangeSet *externalapi.VirtualChangeSet) error {
+	if f.onVirtualChangeHandler != nil && virtualChangeSet != nil {
+		return f.onVirtualChangeHandler(virtualChangeSet)
+	}
+
+	return nil
+}
+
 // OnPruningPointUTXOSetOverride calls the handler function whenever the UTXO set
 // resets due to pruning point change via IBD.
 func (f *FlowContext) OnPruningPointUTXOSetOverride() error {
@@ -71,8 +80,6 @@ func (f *FlowContext) OnPruningPointUTXOSetOverride() error {
 func (f *FlowContext) broadcastTransactionsAfterBlockAdded(
 	addedBlocks []*externalapi.DomainBlock, transactionsAcceptedToMempool []*externalapi.DomainTransaction) error {
 
-	f.updateTransactionsToRebroadcast(addedBlocks)
-
 	// Don't relay transactions when in IBD.
 	if f.IsIBDRunning() {
 		return nil
@@ -80,7 +87,12 @@ func (f *FlowContext) broadcastTransactionsAfterBlockAdded(
 
 	var txIDsToRebroadcast []*externalapi.DomainTransactionID
 	if f.shouldRebroadcastTransactions() {
-		txIDsToRebroadcast = f.txIDsToRebroadcast()
+		txsToRebroadcast, err := f.Domain().MiningManager().RevalidateHighPriorityTransactions()
+		if err != nil {
+			return err
+		}
+		txIDsToRebroadcast = consensushashing.TransactionIDs(txsToRebroadcast)
+		f.lastRebroadcastTime = time.Now()
 	}
 
 	txIDsToBroadcast := make([]*externalapi.DomainTransactionID, len(transactionsAcceptedToMempool)+len(txIDsToRebroadcast))
@@ -91,20 +103,12 @@ func (f *FlowContext) broadcastTransactionsAfterBlockAdded(
 	for i, txID := range txIDsToRebroadcast {
 		txIDsToBroadcast[offset+i] = txID
 	}
-
-	if len(txIDsToBroadcast) == 0 {
-		return nil
-	}
-	if len(txIDsToBroadcast) > appmessage.MaxInvPerTxInvMsg {
-		txIDsToBroadcast = txIDsToBroadcast[:appmessage.MaxInvPerTxInvMsg]
-	}
-	inv := appmessage.NewMsgInvTransaction(txIDsToBroadcast)
-	return f.Broadcast(inv)
+	return f.EnqueueTransactionIDsForPropagation(txIDsToBroadcast)
 }
 
 // SharedRequestedBlocks returns a *blockrelay.SharedRequestedBlocks for sharing
 // data about requested blocks between different peers.
-func (f *FlowContext) SharedRequestedBlocks() *blockrelay.SharedRequestedBlocks {
+func (f *FlowContext) SharedRequestedBlocks() *SharedRequestedBlocks {
 	return f.sharedRequestedBlocks
 }
 
@@ -114,14 +118,14 @@ func (f *FlowContext) AddBlock(block *externalapi.DomainBlock) error {
 		return protocolerrors.Errorf(false, "cannot add header only block")
 	}
 
-	blockInsertionResult, err := f.Domain().Consensus().ValidateAndInsertBlock(block)
+	virtualChangeSet, err := f.Domain().Consensus().ValidateAndInsertBlock(block, true)
 	if err != nil {
 		if errors.As(err, &ruleerrors.RuleError{}) {
 			log.Warnf("Validation failed for block %s: %s", consensushashing.BlockHash(block), err)
 		}
 		return err
 	}
-	err = f.OnNewBlock(block, blockInsertionResult)
+	err = f.OnNewBlock(block, virtualChangeSet)
 	if err != nil {
 		return err
 	}
@@ -161,7 +165,6 @@ func (f *FlowContext) UnsetIBDRunning() {
 	}
 
 	f.ibdPeer = nil
-	log.Infof("IBD finished")
 }
 
 // IBDPeer returns the current IBD peer or null if the node is not

app/protocol/flowcontext/errors.go

@@ -29,3 +29,8 @@ func (*FlowContext) HandleError(err error, flowName string, isStopping *uint32,
 		errChan <- err
 	}
 }
+
+// IsRecoverableError returns whether the error is recoverable
+func (*FlowContext) IsRecoverableError(err error) bool {
+	return err == nil || errors.Is(err, router.ErrRouteClosed) || errors.As(err, &protocolerrors.ProtocolError{})
+}

app/protocol/flowcontext/flow_context.go

@@ -1,16 +1,15 @@
 package flowcontext
 
 import (
-	"github.com/kaspanet/kaspad/util/mstime"
 	"sync"
 	"time"
 
+	"github.com/kaspanet/kaspad/util/mstime"
+
 	"github.com/kaspanet/kaspad/domain/consensus/model/externalapi"
 
 	"github.com/kaspanet/kaspad/domain"
 
-	"github.com/kaspanet/kaspad/app/protocol/flows/blockrelay"
-	"github.com/kaspanet/kaspad/app/protocol/flows/transactionrelay"
 	peerpkg "github.com/kaspanet/kaspad/app/protocol/peer"
 	"github.com/kaspanet/kaspad/infrastructure/config"
 	"github.com/kaspanet/kaspad/infrastructure/network/addressmanager"
@@ -21,7 +20,10 @@ import (
 
 // OnBlockAddedToDAGHandler is a handler function that's triggered
 // when a block is added to the DAG
-type OnBlockAddedToDAGHandler func(block *externalapi.DomainBlock, blockInsertionResult *externalapi.BlockInsertionResult) error
+type OnBlockAddedToDAGHandler func(block *externalapi.DomainBlock, virtualChangeSet *externalapi.VirtualChangeSet) error
+
+// OnVirtualChangeHandler is a handler function that's triggered when the virtual changes
+type OnVirtualChangeHandler func(virtualChangeSet *externalapi.VirtualChangeSet) error
 
 // OnPruningPointUTXOSetOverrideHandler is a handle function that's triggered whenever the UTXO set
 // resets due to pruning point change via IBD.
@@ -42,16 +44,15 @@ type FlowContext struct {
 
 	timeStarted int64
 
+	onVirtualChangeHandler               OnVirtualChangeHandler
 	onBlockAddedToDAGHandler             OnBlockAddedToDAGHandler
 	onPruningPointUTXOSetOverrideHandler OnPruningPointUTXOSetOverrideHandler
 	onTransactionAddedToMempoolHandler   OnTransactionAddedToMempoolHandler
 
-	transactionsToRebroadcastLock sync.Mutex
-	transactionsToRebroadcast     map[externalapi.DomainTransactionID]*externalapi.DomainTransaction
-	lastRebroadcastTime           time.Time
-	sharedRequestedTransactions   *transactionrelay.SharedRequestedTransactions
+	lastRebroadcastTime         time.Time
+	sharedRequestedTransactions *SharedRequestedTransactions
 
-	sharedRequestedBlocks *blockrelay.SharedRequestedBlocks
+	sharedRequestedBlocks *SharedRequestedBlocks
 
 	ibdPeer      *peerpkg.Peer
 	ibdPeerMutex sync.RWMutex
@@ -62,6 +63,10 @@ type FlowContext struct {
 	orphans      map[externalapi.DomainHash]*externalapi.DomainBlock
 	orphansMutex sync.RWMutex
 
+	transactionIDsToPropagate        []*externalapi.DomainTransactionID
+	lastTransactionIDPropagationTime time.Time
+	transactionIDPropagationLock     sync.Mutex
+
 	shutdownChan chan struct{}
 }
 
@@ -70,18 +75,19 @@ func New(cfg *config.Config, domain domain.Domain, addressManager *addressmanage
 	netAdapter *netadapter.NetAdapter, connectionManager *connmanager.ConnectionManager) *FlowContext {
 
 	return &FlowContext{
-		cfg:                         cfg,
-		netAdapter:                  netAdapter,
-		domain:                      domain,
-		addressManager:              addressManager,
-		connectionManager:           connectionManager,
-		sharedRequestedTransactions: transactionrelay.NewSharedRequestedTransactions(),
-		sharedRequestedBlocks:       blockrelay.NewSharedRequestedBlocks(),
-		peers:                       make(map[id.ID]*peerpkg.Peer),
-		transactionsToRebroadcast:   make(map[externalapi.DomainTransactionID]*externalapi.DomainTransaction),
-		orphans:                     make(map[externalapi.DomainHash]*externalapi.DomainBlock),
-		timeStarted:                 mstime.Now().UnixMilliseconds(),
-		shutdownChan:                make(chan struct{}),
+		cfg:                              cfg,
+		netAdapter:                       netAdapter,
+		domain:                           domain,
+		addressManager:                   addressManager,
+		connectionManager:                connectionManager,
+		sharedRequestedTransactions:      NewSharedRequestedTransactions(),
+		sharedRequestedBlocks:            NewSharedRequestedBlocks(),
+		peers:                            make(map[id.ID]*peerpkg.Peer),
+		orphans:                          make(map[externalapi.DomainHash]*externalapi.DomainBlock),
+		timeStarted:                      mstime.Now().UnixMilliseconds(),
+		transactionIDsToPropagate:        []*externalapi.DomainTransactionID{},
+		lastTransactionIDPropagationTime: time.Now(),
+		shutdownChan:                     make(chan struct{}),
 	}
 }
 
@@ -96,6 +102,11 @@ func (f *FlowContext) ShutdownChan() <-chan struct{} {
 	return f.shutdownChan
 }
 
+// SetOnVirtualChangeHandler sets the onVirtualChangeHandler handler
+func (f *FlowContext) SetOnVirtualChangeHandler(onVirtualChangeHandler OnVirtualChangeHandler) {
+	f.onVirtualChangeHandler = onVirtualChangeHandler
+}
+
 // SetOnBlockAddedToDAGHandler sets the onBlockAddedToDAG handler
 func (f *FlowContext) SetOnBlockAddedToDAGHandler(onBlockAddedToDAGHandler OnBlockAddedToDAGHandler) {
 	f.onBlockAddedToDAGHandler = onBlockAddedToDAGHandler

app/protocol/flowcontext/orphans.go

@@ -17,8 +17,8 @@ const maxOrphans = 600
 
 // UnorphaningResult is the result of unorphaning a block
 type UnorphaningResult struct {
-	block                *externalapi.DomainBlock
-	blockInsertionResult *externalapi.BlockInsertionResult
+	block            *externalapi.DomainBlock
+	virtualChangeSet *externalapi.VirtualChangeSet
 }
 
 // AddOrphan adds the block to the orphan set
@@ -73,10 +73,10 @@ func (f *FlowContext) UnorphanBlocks(rootBlock *externalapi.DomainBlock) ([]*Uno
 		orphanBlock := f.orphans[orphanHash]
 
 		log.Debugf("Considering to unorphan block %s with parents %s",
-			orphanHash, orphanBlock.Header.ParentHashes())
+			orphanHash, orphanBlock.Header.DirectParents())
 
 		canBeUnorphaned := true
-		for _, orphanBlockParentHash := range orphanBlock.Header.ParentHashes() {
+		for _, orphanBlockParentHash := range orphanBlock.Header.DirectParents() {
 			orphanBlockParentInfo, err := f.domain.Consensus().GetBlockInfo(orphanBlockParentHash)
 			if err != nil {
 				return nil, err
@@ -90,14 +90,14 @@ func (f *FlowContext) UnorphanBlocks(rootBlock *externalapi.DomainBlock) ([]*Uno
 			}
 		}
 		if canBeUnorphaned {
-			blockInsertionResult, unorphaningSucceeded, err := f.unorphanBlock(orphanHash)
+			virtualChangeSet, unorphaningSucceeded, err := f.unorphanBlock(orphanHash)
 			if err != nil {
 				return nil, err
 			}
 			if unorphaningSucceeded {
 				unorphaningResults = append(unorphaningResults, &UnorphaningResult{
-					block:                orphanBlock,
-					blockInsertionResult: blockInsertionResult,
+					block:            orphanBlock,
+					virtualChangeSet: virtualChangeSet,
 				})
 				processQueue = f.addChildOrphansToProcessQueue(&orphanHash, processQueue)
 			}
@@ -133,7 +133,7 @@ func (f *FlowContext) addChildOrphansToProcessQueue(blockHash *externalapi.Domai
 func (f *FlowContext) findChildOrphansOfBlock(blockHash *externalapi.DomainHash) []externalapi.DomainHash {
 	var childOrphans []externalapi.DomainHash
 	for orphanHash, orphanBlock := range f.orphans {
-		for _, orphanBlockParentHash := range orphanBlock.Header.ParentHashes() {
+		for _, orphanBlockParentHash := range orphanBlock.Header.DirectParents() {
 			if orphanBlockParentHash.Equal(blockHash) {
 				childOrphans = append(childOrphans, orphanHash)
 				break
@@ -143,14 +143,14 @@ func (f *FlowContext) findChildOrphansOfBlock(blockHash *externalapi.DomainHash)
 	return childOrphans
 }
 
-func (f *FlowContext) unorphanBlock(orphanHash externalapi.DomainHash) (*externalapi.BlockInsertionResult, bool, error) {
+func (f *FlowContext) unorphanBlock(orphanHash externalapi.DomainHash) (*externalapi.VirtualChangeSet, bool, error) {
 	orphanBlock, ok := f.orphans[orphanHash]
 	if !ok {
 		return nil, false, errors.Errorf("attempted to unorphan a non-orphan block %s", orphanHash)
 	}
 	delete(f.orphans, orphanHash)
 
-	blockInsertionResult, err := f.domain.Consensus().ValidateAndInsertBlock(orphanBlock)
+	virtualChangeSet, err := f.domain.Consensus().ValidateAndInsertBlock(orphanBlock, true)
 	if err != nil {
 		if errors.As(err, &ruleerrors.RuleError{}) {
 			log.Warnf("Validation failed for orphan block %s: %s", orphanHash, err)
@@ -160,7 +160,7 @@ func (f *FlowContext) unorphanBlock(orphanHash externalapi.DomainHash) (*externa
 	}
 
 	log.Infof("Unorphaned block %s", orphanHash)
-	return blockInsertionResult, true, nil
+	return virtualChangeSet, true, nil
 }
 
 // GetOrphanRoots returns the roots of the missing ancestors DAG of the given orphan
@@ -201,7 +201,7 @@ func (f *FlowContext) GetOrphanRoots(orphan *externalapi.DomainHash) ([]*externa
 			continue
 		}
 
-		for _, parent := range block.Header.ParentHashes() {
+		for _, parent := range block.Header.DirectParents() {
 			if !addedToQueueSet.Contains(parent) {
 				queue = append(queue, parent)
 				addedToQueueSet.Add(parent)

app/protocol/flowcontext/shared_requested_blocks.go

@@ -1,4 +1,4 @@
-package blockrelay
+package flowcontext
 
 import (
 	"sync"
@@ -13,13 +13,15 @@ type SharedRequestedBlocks struct {
 	sync.Mutex
 }
 
-func (s *SharedRequestedBlocks) remove(hash *externalapi.DomainHash) {
+// Remove removes a block from the set.
+func (s *SharedRequestedBlocks) Remove(hash *externalapi.DomainHash) {
 	s.Lock()
 	defer s.Unlock()
 	delete(s.blocks, *hash)
 }
 
-func (s *SharedRequestedBlocks) removeSet(blockHashes map[externalapi.DomainHash]struct{}) {
+// RemoveSet removes a set of blocks from the set.
+func (s *SharedRequestedBlocks) RemoveSet(blockHashes map[externalapi.DomainHash]struct{}) {
 	s.Lock()
 	defer s.Unlock()
 	for hash := range blockHashes {
@@ -27,7 +29,8 @@ func (s *SharedRequestedBlocks) removeSet(blockHashes map[externalapi.DomainHash
 	}
 }
 
-func (s *SharedRequestedBlocks) addIfNotExists(hash *externalapi.DomainHash) (exists bool) {
+// AddIfNotExists adds a block to the set if it doesn't exist yet.
+func (s *SharedRequestedBlocks) AddIfNotExists(hash *externalapi.DomainHash) (exists bool) {
 	s.Lock()
 	defer s.Unlock()
 	_, ok := s.blocks[*hash]

app/protocol/flowcontext/shared_requested_transactions.go

@@ -1,4 +1,4 @@
-package transactionrelay
+package flowcontext
 
 import (
 	"sync"
@@ -13,13 +13,15 @@ type SharedRequestedTransactions struct {
 	sync.Mutex
 }
 
-func (s *SharedRequestedTransactions) remove(txID *externalapi.DomainTransactionID) {
+// Remove removes a transaction from the set.
+func (s *SharedRequestedTransactions) Remove(txID *externalapi.DomainTransactionID) {
 	s.Lock()
 	defer s.Unlock()
 	delete(s.transactions, *txID)
 }
 
-func (s *SharedRequestedTransactions) removeMany(txIDs []*externalapi.DomainTransactionID) {
+// RemoveMany removes a set of transactions from the set.
+func (s *SharedRequestedTransactions) RemoveMany(txIDs []*externalapi.DomainTransactionID) {
 	s.Lock()
 	defer s.Unlock()
 	for _, txID := range txIDs {
@@ -27,7 +29,8 @@ func (s *SharedRequestedTransactions) removeMany(txIDs []*externalapi.DomainTran
 	}
 }
 
-func (s *SharedRequestedTransactions) addIfNotExists(txID *externalapi.DomainTransactionID) (exists bool) {
+// AddIfNotExists adds a transaction to the set if it doesn't exist yet.
+func (s *SharedRequestedTransactions) AddIfNotExists(txID *externalapi.DomainTransactionID) (exists bool) {
 	s.Lock()
 	defer s.Unlock()
 	_, ok := s.transactions[*txID]

app/protocol/flowcontext/should_mine.go

@@ -25,6 +25,10 @@ func (f *FlowContext) ShouldMine() (bool, error) {
 		return false, err
 	}
 
+	if virtualSelectedParent.Equal(f.Config().NetParams().GenesisHash) {
+		return false, nil
+	}
+
 	virtualSelectedParentHeader, err := f.domain.Consensus().GetBlockHeader(virtualSelectedParent)
 	if err != nil {
 		return false, err

app/protocol/flowcontext/transactions.go

@@ -4,39 +4,22 @@ import (
 	"time"
 
 	"github.com/kaspanet/kaspad/app/appmessage"
-	"github.com/kaspanet/kaspad/app/protocol/flows/transactionrelay"
 	"github.com/kaspanet/kaspad/domain/consensus/model/externalapi"
 	"github.com/kaspanet/kaspad/domain/consensus/utils/consensushashing"
 )
 
-// AddTransaction adds transaction to the mempool and propagates it.
-func (f *FlowContext) AddTransaction(tx *externalapi.DomainTransaction) error {
-	f.transactionsToRebroadcastLock.Lock()
-	defer f.transactionsToRebroadcastLock.Unlock()
+// TransactionIDPropagationInterval is the interval between transaction IDs propagations
+const TransactionIDPropagationInterval = 500 * time.Millisecond
 
-	err := f.Domain().MiningManager().ValidateAndInsertTransaction(tx, false)
+// AddTransaction adds transaction to the mempool and propagates it.
+func (f *FlowContext) AddTransaction(tx *externalapi.DomainTransaction, allowOrphan bool) error {
+	acceptedTransactions, err := f.Domain().MiningManager().ValidateAndInsertTransaction(tx, true, allowOrphan)
 	if err != nil {
 		return err
 	}
 
-	transactionID := consensushashing.TransactionID(tx)
-	f.transactionsToRebroadcast[*transactionID] = tx
-	inv := appmessage.NewMsgInvTransaction([]*externalapi.DomainTransactionID{transactionID})
-	return f.Broadcast(inv)
-}
-
-func (f *FlowContext) updateTransactionsToRebroadcast(addedBlocks []*externalapi.DomainBlock) {
-	f.transactionsToRebroadcastLock.Lock()
-	defer f.transactionsToRebroadcastLock.Unlock()
-
-	for _, block := range addedBlocks {
-		// Note: if a transaction is included in the DAG but not accepted,
-		// it won't be rebroadcast anymore, although it is not included in
-		// the UTXO set
-		for _, tx := range block.Transactions {
-			delete(f.transactionsToRebroadcast, *consensushashing.TransactionID(tx))
-		}
-	}
+	acceptedTransactionIDs := consensushashing.TransactionIDs(acceptedTransactions)
+	return f.EnqueueTransactionIDsForPropagation(acceptedTransactionIDs)
 }
 
 func (f *FlowContext) shouldRebroadcastTransactions() bool {
@@ -44,22 +27,9 @@ func (f *FlowContext) shouldRebroadcastTransactions() bool {
 	return time.Since(f.lastRebroadcastTime) > rebroadcastInterval
 }
 
-func (f *FlowContext) txIDsToRebroadcast() []*externalapi.DomainTransactionID {
-	f.transactionsToRebroadcastLock.Lock()
-	defer f.transactionsToRebroadcastLock.Unlock()
-
-	txIDs := make([]*externalapi.DomainTransactionID, len(f.transactionsToRebroadcast))
-	i := 0
-	for _, tx := range f.transactionsToRebroadcast {
-		txIDs[i] = consensushashing.TransactionID(tx)
-		i++
-	}
-	return txIDs
-}
-
 // SharedRequestedTransactions returns a *transactionrelay.SharedRequestedTransactions for sharing
 // data about requested transactions between different peers.
-func (f *FlowContext) SharedRequestedTransactions() *transactionrelay.SharedRequestedTransactions {
+func (f *FlowContext) SharedRequestedTransactions() *SharedRequestedTransactions {
 	return f.sharedRequestedTransactions
 }
 
@@ -70,3 +40,42 @@ func (f *FlowContext) OnTransactionAddedToMempool() {
 		f.onTransactionAddedToMempoolHandler()
 	}
 }
+
+// EnqueueTransactionIDsForPropagation add the given transactions IDs to a set of IDs to
+// propagate. The IDs will be broadcast to all peers within a single transaction Inv message.
+// The broadcast itself may happen only during a subsequent call to this method
+func (f *FlowContext) EnqueueTransactionIDsForPropagation(transactionIDs []*externalapi.DomainTransactionID) error {
+	f.transactionIDPropagationLock.Lock()
+	defer f.transactionIDPropagationLock.Unlock()
+
+	f.transactionIDsToPropagate = append(f.transactionIDsToPropagate, transactionIDs...)
+
+	return f.maybePropagateTransactions()
+}
+
+func (f *FlowContext) maybePropagateTransactions() error {
+	if time.Since(f.lastTransactionIDPropagationTime) < TransactionIDPropagationInterval &&
+		len(f.transactionIDsToPropagate) < appmessage.MaxInvPerTxInvMsg {
+		return nil
+	}
+
+	for len(f.transactionIDsToPropagate) > 0 {
+		transactionIDsToBroadcast := f.transactionIDsToPropagate
+		if len(transactionIDsToBroadcast) > appmessage.MaxInvPerTxInvMsg {
+			transactionIDsToBroadcast = f.transactionIDsToPropagate[:len(transactionIDsToBroadcast)]
+		}
+		log.Debugf("Transaction propagation: broadcasting %d transactions", len(transactionIDsToBroadcast))
+
+		inv := appmessage.NewMsgInvTransaction(transactionIDsToBroadcast)
+		err := f.Broadcast(inv)
+		if err != nil {
+			return err
+		}
+
+		f.transactionIDsToPropagate = f.transactionIDsToPropagate[len(transactionIDsToBroadcast):]
+	}
+
+	f.lastTransactionIDPropagationTime = time.Now()
+
+	return nil
+}

app/protocol/flows/blockrelay/block_locator.go

@@ -1,29 +0,0 @@
-package blockrelay
-
-import (
-	"github.com/kaspanet/kaspad/app/appmessage"
-	"github.com/kaspanet/kaspad/app/protocol/common"
-	"github.com/kaspanet/kaspad/app/protocol/protocolerrors"
-	"github.com/kaspanet/kaspad/domain/consensus/model/externalapi"
-)
-
-func (flow *handleRelayInvsFlow) sendGetBlockLocator(lowHash *externalapi.DomainHash,
-	highHash *externalapi.DomainHash, limit uint32) error {
-
-	msgGetBlockLocator := appmessage.NewMsgRequestBlockLocator(lowHash, highHash, limit)
-	return flow.outgoingRoute.Enqueue(msgGetBlockLocator)
-}
-
-func (flow *handleRelayInvsFlow) receiveBlockLocator() (blockLocatorHashes []*externalapi.DomainHash, err error) {
-	message, err := flow.dequeueIncomingMessageAndSkipInvs(common.DefaultTimeout)
-	if err != nil {
-		return nil, err
-	}
-	msgBlockLocator, ok := message.(*appmessage.MsgBlockLocator)
-	if !ok {
-		return nil,
-			protocolerrors.Errorf(true, "received unexpected message type. "+
-				"expected: %s, got: %s", appmessage.CmdBlockLocator, message.Command())
-	}
-	return msgBlockLocator.BlockLocatorHashes, nil
-}

app/protocol/flows/blockrelay/handle_pruning_point_hash_requests.go

@@ -1,51 +0,0 @@
-package blockrelay
-
-import (
-	"github.com/kaspanet/kaspad/app/appmessage"
-	"github.com/kaspanet/kaspad/domain"
-	"github.com/kaspanet/kaspad/infrastructure/network/netadapter/router"
-)
-
-// HandlePruningPointHashRequestsFlowContext is the interface for the context needed for the handlePruningPointHashRequestsFlow flow.
-type HandlePruningPointHashRequestsFlowContext interface {
-	Domain() domain.Domain
-}
-
-type handlePruningPointHashRequestsFlow struct {
-	HandlePruningPointHashRequestsFlowContext
-	incomingRoute, outgoingRoute *router.Route
-}
-
-// HandlePruningPointHashRequests listens to appmessage.MsgRequestPruningPointHashMessage messages and sends
-// the pruning point hash as response.
-func HandlePruningPointHashRequests(context HandlePruningPointHashRequestsFlowContext, incomingRoute,
-	outgoingRoute *router.Route) error {
-	flow := &handlePruningPointHashRequestsFlow{
-		HandlePruningPointHashRequestsFlowContext: context,
-		incomingRoute: incomingRoute,
-		outgoingRoute: outgoingRoute,
-	}
-
-	return flow.start()
-}
-
-func (flow *handlePruningPointHashRequestsFlow) start() error {
-	for {
-		_, err := flow.incomingRoute.Dequeue()
-		if err != nil {
-			return err
-		}
-		log.Debugf("Got request for a pruning point hash")
-
-		pruningPoint, err := flow.Domain().Consensus().PruningPoint()
-		if err != nil {
-			return err
-		}
-
-		err = flow.outgoingRoute.Enqueue(appmessage.NewPruningPointHashMessage(pruningPoint))
-		if err != nil {
-			return err
-		}
-		log.Debugf("Sent pruning point hash %s", pruningPoint)
-	}
-}

app/protocol/flows/blockrelay/handle_request_pruning_point_utxo_set_and_block.go

@@ -1,144 +0,0 @@
-package blockrelay
-
-import (
-	"errors"
-	"github.com/kaspanet/kaspad/app/appmessage"
-	"github.com/kaspanet/kaspad/app/protocol/common"
-	"github.com/kaspanet/kaspad/app/protocol/protocolerrors"
-	"github.com/kaspanet/kaspad/domain"
-	"github.com/kaspanet/kaspad/domain/consensus/model/externalapi"
-	"github.com/kaspanet/kaspad/domain/consensus/ruleerrors"
-	"github.com/kaspanet/kaspad/infrastructure/logger"
-	"github.com/kaspanet/kaspad/infrastructure/network/netadapter/router"
-)
-
-// HandleRequestPruningPointUTXOSetAndBlockContext is the interface for the context needed for the HandleRequestPruningPointUTXOSetAndBlock flow.
-type HandleRequestPruningPointUTXOSetAndBlockContext interface {
-	Domain() domain.Domain
-}
-
-type handleRequestPruningPointUTXOSetAndBlockFlow struct {
-	HandleRequestPruningPointUTXOSetAndBlockContext
-	incomingRoute, outgoingRoute *router.Route
-}
-
-// HandleRequestPruningPointUTXOSetAndBlock listens to appmessage.MsgRequestPruningPointUTXOSetAndBlock messages and sends
-// the pruning point UTXO set and block body.
-func HandleRequestPruningPointUTXOSetAndBlock(context HandleRequestPruningPointUTXOSetAndBlockContext, incomingRoute,
-	outgoingRoute *router.Route) error {
-	flow := &handleRequestPruningPointUTXOSetAndBlockFlow{
-		HandleRequestPruningPointUTXOSetAndBlockContext: context,
-		incomingRoute: incomingRoute,
-		outgoingRoute: outgoingRoute,
-	}
-
-	return flow.start()
-}
-
-func (flow *handleRequestPruningPointUTXOSetAndBlockFlow) start() error {
-	for {
-		msgRequestPruningPointUTXOSetAndBlock, err := flow.waitForRequestPruningPointUTXOSetAndBlockMessages()
-		if err != nil {
-			return err
-		}
-
-		err = flow.handleRequestPruningPointUTXOSetAndBlockMessage(msgRequestPruningPointUTXOSetAndBlock)
-		if err != nil {
-			return err
-		}
-	}
-}
-
-func (flow *handleRequestPruningPointUTXOSetAndBlockFlow) handleRequestPruningPointUTXOSetAndBlockMessage(
-	msgRequestPruningPointUTXOSetAndBlock *appmessage.MsgRequestPruningPointUTXOSetAndBlock) error {
-
-	onEnd := logger.LogAndMeasureExecutionTime(log, "handleRequestPruningPointUTXOSetAndBlockFlow")
-	defer onEnd()
-
-	log.Debugf("Got request for PruningPointHash UTXOSet and Block")
-
-	err := flow.sendPruningPointBlock(msgRequestPruningPointUTXOSetAndBlock)
-	if err != nil {
-		return err
-	}
-
-	return flow.sendPruningPointUTXOSet(msgRequestPruningPointUTXOSetAndBlock)
-}
-
-func (flow *handleRequestPruningPointUTXOSetAndBlockFlow) waitForRequestPruningPointUTXOSetAndBlockMessages() (
-	*appmessage.MsgRequestPruningPointUTXOSetAndBlock, error) {
-
-	message, err := flow.incomingRoute.Dequeue()
-	if err != nil {
-		return nil, err
-	}
-	msgRequestPruningPointUTXOSetAndBlock, ok := message.(*appmessage.MsgRequestPruningPointUTXOSetAndBlock)
-	if !ok {
-		return nil, protocolerrors.Errorf(true, "received unexpected message type. "+
-			"expected: %s, got: %s", appmessage.CmdRequestPruningPointUTXOSetAndBlock, message.Command())
-	}
-	return msgRequestPruningPointUTXOSetAndBlock, nil
-}
-
-func (flow *handleRequestPruningPointUTXOSetAndBlockFlow) sendPruningPointBlock(
-	msgRequestPruningPointUTXOSetAndBlock *appmessage.MsgRequestPruningPointUTXOSetAndBlock) error {
-
-	block, err := flow.Domain().Consensus().GetBlock(msgRequestPruningPointUTXOSetAndBlock.PruningPointHash)
-	if err != nil {
-		return err
-	}
-	log.Debugf("Retrieved pruning block %s", msgRequestPruningPointUTXOSetAndBlock.PruningPointHash)
-
-	return flow.outgoingRoute.Enqueue(appmessage.NewMsgIBDBlock(appmessage.DomainBlockToMsgBlock(block)))
-}
-
-func (flow *handleRequestPruningPointUTXOSetAndBlockFlow) sendPruningPointUTXOSet(
-	msgRequestPruningPointUTXOSetAndBlock *appmessage.MsgRequestPruningPointUTXOSetAndBlock) error {
-
-	// Send the UTXO set in `step`-sized chunks
-	const step = 1000
-	var fromOutpoint *externalapi.DomainOutpoint
-	chunksSent := 0
-	for {
-		pruningPointUTXOs, err := flow.Domain().Consensus().GetPruningPointUTXOs(
-			msgRequestPruningPointUTXOSetAndBlock.PruningPointHash, fromOutpoint, step)
-		if err != nil {
-			if errors.Is(err, ruleerrors.ErrWrongPruningPointHash) {
-				return flow.outgoingRoute.Enqueue(appmessage.NewMsgUnexpectedPruningPoint())
-			}
-		}
-
-		log.Debugf("Retrieved %d UTXOs for pruning block %s",
-			len(pruningPointUTXOs), msgRequestPruningPointUTXOSetAndBlock.PruningPointHash)
-
-		outpointAndUTXOEntryPairs :=
-			appmessage.DomainOutpointAndUTXOEntryPairsToOutpointAndUTXOEntryPairs(pruningPointUTXOs)
-		err = flow.outgoingRoute.Enqueue(appmessage.NewMsgPruningPointUTXOSetChunk(outpointAndUTXOEntryPairs))
-		if err != nil {
-			return err
-		}
-
-		if len(pruningPointUTXOs) < step {
-			log.Debugf("Finished sending UTXOs for pruning block %s",
-				msgRequestPruningPointUTXOSetAndBlock.PruningPointHash)
-
-			return flow.outgoingRoute.Enqueue(appmessage.NewMsgDonePruningPointUTXOSetChunks())
-		}
-
-		fromOutpoint = pruningPointUTXOs[len(pruningPointUTXOs)-1].Outpoint
-		chunksSent++
-
-		// Wait for the peer to request more chunks every `ibdBatchSize` chunks
-		if chunksSent%ibdBatchSize == 0 {
-			message, err := flow.incomingRoute.DequeueWithTimeout(common.DefaultTimeout)
-			if err != nil {
-				return err
-			}
-			_, ok := message.(*appmessage.MsgRequestNextPruningPointUTXOSetChunk)
-			if !ok {
-				return protocolerrors.Errorf(true, "received unexpected message type. "+
-					"expected: %s, got: %s", appmessage.CmdRequestNextPruningPointUTXOSetChunk, message.Command())
-			}
-		}
-	}
-}

app/protocol/flows/handshake/handshake.go

@@ -28,7 +28,7 @@ type HandleHandshakeContext interface {
 	HandleError(err error, flowName string, isStopping *uint32, errChan chan<- error)
 }
 
-// HandleHandshake sets up the handshake protocol - It sends a version message and waits for an incoming
+// HandleHandshake sets up the new_handshake protocol - It sends a version message and waits for an incoming
 // version message, as well as a verack for the sent version
 func HandleHandshake(context HandleHandshakeContext, netConnection *netadapter.NetConnection,
 	receiveVersionRoute *routerpkg.Route, sendVersionRoute *routerpkg.Route, outgoingRoute *routerpkg.Route,
@@ -98,7 +98,7 @@ func HandleHandshake(context HandleHandshakeContext, netConnection *netadapter.N
 }
 
 // Handshake is different from other flows, since in it should forward router.ErrRouteClosed to errChan
-// Therefore we implement a separate handleError for handshake
+// Therefore we implement a separate handleError for new_handshake
 func handleError(err error, flowName string, isStopping *uint32, errChan chan error) {
 	if errors.Is(err, routerpkg.ErrRouteClosed) {
 		if atomic.AddUint32(isStopping, 1) == 1 {

app/protocol/flows/handshake/receiveversion.go

@@ -7,6 +7,7 @@ import (
 	"github.com/kaspanet/kaspad/app/protocol/protocolerrors"
 	"github.com/kaspanet/kaspad/infrastructure/logger"
 	"github.com/kaspanet/kaspad/infrastructure/network/netadapter/router"
+	"github.com/pkg/errors"
 )
 
 var (
@@ -17,7 +18,9 @@ var (
 
 	// minAcceptableProtocolVersion is the lowest protocol version that a
 	// connected peer may support.
-	minAcceptableProtocolVersion = appmessage.ProtocolVersion
+	minAcceptableProtocolVersion = uint32(4)
+
+	maxAcceptableProtocolVersion = uint32(4)
 )
 
 type receiveVersionFlow struct {
@@ -97,7 +100,12 @@ func (flow *receiveVersionFlow) start() (*appmessage.NetAddress, error) {
 		return nil, protocolerrors.New(false, "incompatible subnetworks")
 	}
 
-	flow.peer.UpdateFieldsFromMsgVersion(msgVersion)
+	if flow.Config().ProtocolVersion > maxAcceptableProtocolVersion {
+		return nil, errors.Errorf("%d is a non existing protocol version", flow.Config().ProtocolVersion)
+	}
+
+	maxProtocolVersion := flow.Config().ProtocolVersion
+	flow.peer.UpdateFieldsFromMsgVersion(msgVersion, maxProtocolVersion)
 	err = flow.outgoingRoute.Enqueue(appmessage.NewMsgVerAck())
 	if err != nil {
 		return nil, err

app/protocol/flows/handshake/sendversion.go

@@ -7,6 +7,7 @@ import (
 	"github.com/kaspanet/kaspad/infrastructure/logger"
 	"github.com/kaspanet/kaspad/infrastructure/network/netadapter/router"
 	"github.com/kaspanet/kaspad/version"
+	"github.com/pkg/errors"
 )
 
 var (
@@ -56,15 +57,18 @@ func (flow *sendVersionFlow) start() error {
 	// Version message.
 	localAddress := flow.AddressManager().BestLocalAddress(flow.peer.Connection().NetAddress())
 	subnetworkID := flow.Config().SubnetworkID
+	if flow.Config().ProtocolVersion < minAcceptableProtocolVersion {
+		return errors.Errorf("configured protocol version %d is obsolete", flow.Config().ProtocolVersion)
+	}
 	msg := appmessage.NewMsgVersion(localAddress, flow.NetAdapter().ID(),
-		flow.Config().ActiveNetParams.Name, subnetworkID)
+		flow.Config().ActiveNetParams.Name, subnetworkID, flow.Config().ProtocolVersion)
 	msg.AddUserAgent(userAgentName, userAgentVersion, flow.Config().UserAgentComments...)
 
 	// Advertise the services flag
 	msg.Services = defaultServices
 
 	// Advertise our max supported protocol version.
-	msg.ProtocolVersion = appmessage.ProtocolVersion
+	msg.ProtocolVersion = flow.Config().ProtocolVersion
 
 	// Advertise if inv messages for transactions are desired.
 	msg.DisableRelayTx = flow.Config().BlocksOnly

app/protocol/flows/ready/log.go

@@ -0,0 +1,9 @@
+package ready
+
+import (
+	"github.com/kaspanet/kaspad/infrastructure/logger"
+	"github.com/kaspanet/kaspad/util/panics"
+)
+
+var log = logger.RegisterSubSystem("PROT")
+var spawn = panics.GoroutineWrapperFunc(log)

app/protocol/flows/ready/ready.go

@@ -0,0 +1,56 @@
+package ready
+
+import (
+	"github.com/kaspanet/kaspad/app/appmessage"
+	"github.com/kaspanet/kaspad/app/protocol/common"
+	"sync/atomic"
+
+	peerpkg "github.com/kaspanet/kaspad/app/protocol/peer"
+	"github.com/kaspanet/kaspad/app/protocol/protocolerrors"
+	routerpkg "github.com/kaspanet/kaspad/infrastructure/network/netadapter/router"
+	"github.com/pkg/errors"
+)
+
+// HandleReady notify the other peer that peer is ready for messages, and wait for the other peer
+// to send a ready message before start running the flows.
+func HandleReady(incomingRoute *routerpkg.Route, outgoingRoute *routerpkg.Route,
+	peer *peerpkg.Peer,
+) error {
+
+	log.Debugf("Sending ready message to %s", peer)
+
+	isStopping := uint32(0)
+	err := outgoingRoute.Enqueue(appmessage.NewMsgReady())
+	if err != nil {
+		return handleError(err, "HandleReady", &isStopping)
+	}
+
+	_, err = incomingRoute.DequeueWithTimeout(common.DefaultTimeout)
+	if err != nil {
+		return handleError(err, "HandleReady", &isStopping)
+	}
+
+	log.Debugf("Got ready message from %s", peer)
+
+	return nil
+}
+
+// Ready is different from other flows, since in it should forward router.ErrRouteClosed to errChan
+// Therefore we implement a separate handleError for 'ready'
+func handleError(err error, flowName string, isStopping *uint32) error {
+	if errors.Is(err, routerpkg.ErrRouteClosed) {
+		if atomic.AddUint32(isStopping, 1) == 1 {
+			return err
+		}
+		return nil
+	}
+
+	if protocolErr := (protocolerrors.ProtocolError{}); errors.As(err, &protocolErr) {
+		log.Errorf("Ready protocol error from %s: %s", flowName, err)
+		if atomic.AddUint32(isStopping, 1) == 1 {
+			return err
+		}
+		return nil
+	}
+	panic(err)
+}

app/protocol/flows/v4/blockrelay/block_locator.go

@@ -0,0 +1,33 @@
+package blockrelay
+
+import (
+	"github.com/kaspanet/kaspad/app/appmessage"
+	"github.com/kaspanet/kaspad/app/protocol/common"
+	"github.com/kaspanet/kaspad/app/protocol/protocolerrors"
+	"github.com/kaspanet/kaspad/domain/consensus/model/externalapi"
+)
+
+func (flow *handleRelayInvsFlow) sendGetBlockLocator(highHash *externalapi.DomainHash, limit uint32) error {
+	msgGetBlockLocator := appmessage.NewMsgRequestBlockLocator(highHash, limit)
+	return flow.outgoingRoute.Enqueue(msgGetBlockLocator)
+}
+
+func (flow *handleRelayInvsFlow) receiveBlockLocator() (blockLocatorHashes []*externalapi.DomainHash, err error) {
+	for {
+		message, err := flow.incomingRoute.DequeueWithTimeout(common.DefaultTimeout)
+		if err != nil {
+			return nil, err
+		}
+
+		switch message := message.(type) {
+		case *appmessage.MsgInvRelayBlock:
+			flow.invsQueue = append(flow.invsQueue, message)
+		case *appmessage.MsgBlockLocator:
+			return message.BlockLocatorHashes, nil
+		default:
+			return nil,
+				protocolerrors.Errorf(true, "received unexpected message type. "+
+					"expected: %s, got: %s", appmessage.CmdBlockLocator, message.Command())
+		}
+	}
+}

app/protocol/flows/v4/blockrelay/handle_ibd_block_locator.go

@@ -5,6 +5,7 @@ import (
 	"github.com/kaspanet/kaspad/app/protocol/peer"
 	"github.com/kaspanet/kaspad/app/protocol/protocolerrors"
 	"github.com/kaspanet/kaspad/domain"
+	"github.com/kaspanet/kaspad/domain/consensus/model/externalapi"
 	"github.com/kaspanet/kaspad/infrastructure/network/netadapter/router"
 )
 
@@ -44,7 +45,9 @@ func HandleIBDBlockLocator(context HandleIBDBlockLocatorContext, incomingRoute *
 			if err != nil {
 				return err
 			}
-			if !blockInfo.Exists {
+
+			// The IBD block locator is checking only existing blocks with bodies.
+			if !blockInfo.Exists || blockInfo.BlockStatus == externalapi.StatusHeaderOnly {
 				continue
 			}
 

app/protocol/flows/v4/blockrelay/handle_ibd_block_requests.go

@@ -48,7 +48,7 @@ func HandleIBDBlockRequests(context HandleIBDBlockRequestsContext, incomingRoute
 			if err != nil {
 				return err
 			}
-			log.Debugf("sent %d out of %d", i, len(msgRequestIBDBlocks.Hashes))
+			log.Debugf("sent %d out of %d", i+1, len(msgRequestIBDBlocks.Hashes))
 		}
 	}
 }

app/protocol/flows/v4/blockrelay/handle_pruning_point_and_its_anticone_requests.go

@@ -0,0 +1,145 @@
+package blockrelay
+
+import (
+	"github.com/kaspanet/kaspad/app/appmessage"
+	peerpkg "github.com/kaspanet/kaspad/app/protocol/peer"
+	"github.com/kaspanet/kaspad/app/protocol/protocolerrors"
+	"github.com/kaspanet/kaspad/domain"
+	"github.com/kaspanet/kaspad/domain/consensus/model/externalapi"
+	"github.com/kaspanet/kaspad/infrastructure/config"
+	"github.com/kaspanet/kaspad/infrastructure/network/netadapter/router"
+	"sync/atomic"
+)
+
+// PruningPointAndItsAnticoneRequestsContext is the interface for the context needed for the HandlePruningPointAndItsAnticoneRequests flow.
+type PruningPointAndItsAnticoneRequestsContext interface {
+	Domain() domain.Domain
+	Config() *config.Config
+}
+
+var isBusy uint32
+
+// HandlePruningPointAndItsAnticoneRequests listens to appmessage.MsgRequestPruningPointAndItsAnticone messages and sends
+// the pruning point and its anticone to the requesting peer.
+func HandlePruningPointAndItsAnticoneRequests(context PruningPointAndItsAnticoneRequestsContext, incomingRoute *router.Route,
+	outgoingRoute *router.Route, peer *peerpkg.Peer) error {
+
+	for {
+		err := func() error {
+			_, err := incomingRoute.Dequeue()
+			if err != nil {
+				return err
+			}
+
+			if !atomic.CompareAndSwapUint32(&isBusy, 0, 1) {
+				return protocolerrors.Errorf(false, "node is busy with other pruning point anticone requests")
+			}
+			defer atomic.StoreUint32(&isBusy, 0)
+
+			log.Debugf("Got request for pruning point and its anticone from %s", peer)
+
+			pruningPointHeaders, err := context.Domain().Consensus().PruningPointHeaders()
+			if err != nil {
+				return err
+			}
+
+			msgPruningPointHeaders := make([]*appmessage.MsgBlockHeader, len(pruningPointHeaders))
+			for i, header := range pruningPointHeaders {
+				msgPruningPointHeaders[i] = appmessage.DomainBlockHeaderToBlockHeader(header)
+			}
+
+			err = outgoingRoute.Enqueue(appmessage.NewMsgPruningPoints(msgPruningPointHeaders))
+			if err != nil {
+				return err
+			}
+
+			pointAndItsAnticone, err := context.Domain().Consensus().PruningPointAndItsAnticone()
+			if err != nil {
+				return err
+			}
+
+			windowSize := context.Config().NetParams().DifficultyAdjustmentWindowSize
+			daaWindowBlocks := make([]*externalapi.TrustedDataDataDAAHeader, 0, windowSize)
+			daaWindowHashesToIndex := make(map[externalapi.DomainHash]int, windowSize)
+			trustedDataDAABlockIndexes := make(map[externalapi.DomainHash][]uint64)
+
+			ghostdagData := make([]*externalapi.BlockGHOSTDAGDataHashPair, 0)
+			ghostdagDataHashToIndex := make(map[externalapi.DomainHash]int)
+			trustedDataGHOSTDAGDataIndexes := make(map[externalapi.DomainHash][]uint64)
+			for _, blockHash := range pointAndItsAnticone {
+				blockDAAWindowHashes, err := context.Domain().Consensus().BlockDAAWindowHashes(blockHash)
+				if err != nil {
+					return err
+				}
+
+				trustedDataDAABlockIndexes[*blockHash] = make([]uint64, 0, windowSize)
+				for i, daaBlockHash := range blockDAAWindowHashes {
+					index, exists := daaWindowHashesToIndex[*daaBlockHash]
+					if !exists {
+						trustedDataDataDAAHeader, err := context.Domain().Consensus().TrustedDataDataDAAHeader(blockHash, daaBlockHash, uint64(i))
+						if err != nil {
+							return err
+						}
+						daaWindowBlocks = append(daaWindowBlocks, trustedDataDataDAAHeader)
+						index = len(daaWindowBlocks) - 1
+						daaWindowHashesToIndex[*daaBlockHash] = index
+					}
+
+					trustedDataDAABlockIndexes[*blockHash] = append(trustedDataDAABlockIndexes[*blockHash], uint64(index))
+				}
+
+				ghostdagDataBlockHashes, err := context.Domain().Consensus().TrustedBlockAssociatedGHOSTDAGDataBlockHashes(blockHash)
+				if err != nil {
+					return err
+				}
+
+				trustedDataGHOSTDAGDataIndexes[*blockHash] = make([]uint64, 0, context.Config().NetParams().K)
+				for _, ghostdagDataBlockHash := range ghostdagDataBlockHashes {
+					index, exists := ghostdagDataHashToIndex[*ghostdagDataBlockHash]
+					if !exists {
+						data, err := context.Domain().Consensus().TrustedGHOSTDAGData(ghostdagDataBlockHash)
+						if err != nil {
+							return err
+						}
+						ghostdagData = append(ghostdagData, &externalapi.BlockGHOSTDAGDataHashPair{
+							Hash:         ghostdagDataBlockHash,
+							GHOSTDAGData: data,
+						})
+						index = len(ghostdagData) - 1
+						ghostdagDataHashToIndex[*ghostdagDataBlockHash] = index
+					}
+
+					trustedDataGHOSTDAGDataIndexes[*blockHash] = append(trustedDataGHOSTDAGDataIndexes[*blockHash], uint64(index))
+				}
+			}
+
+			err = outgoingRoute.Enqueue(appmessage.DomainTrustedDataToTrustedData(daaWindowBlocks, ghostdagData))
+			if err != nil {
+				return err
+			}
+
+			for _, blockHash := range pointAndItsAnticone {
+				block, err := context.Domain().Consensus().GetBlock(blockHash)
+				if err != nil {
+					return err
+				}
+
+				err = outgoingRoute.Enqueue(appmessage.DomainBlockWithTrustedDataToBlockWithTrustedDataV4(block, trustedDataDAABlockIndexes[*blockHash], trustedDataGHOSTDAGDataIndexes[*blockHash]))
+				if err != nil {
+					return err
+				}
+			}
+
+			err = outgoingRoute.Enqueue(appmessage.NewMsgDoneBlocksWithTrustedData())
+			if err != nil {
+				return err
+			}
+
+			log.Debugf("Sent pruning point and its anticone to %s", peer)
+			return nil
+		}()
+		if err != nil {
+			return err
+		}
+	}
+}

app/protocol/flows/v4/blockrelay/handle_pruning_point_proof_requests.go

@@ -0,0 +1,40 @@
+package blockrelay
+
+import (
+	"github.com/kaspanet/kaspad/app/appmessage"
+	peerpkg "github.com/kaspanet/kaspad/app/protocol/peer"
+	"github.com/kaspanet/kaspad/domain"
+	"github.com/kaspanet/kaspad/infrastructure/network/netadapter/router"
+)
+
+// PruningPointProofRequestsContext is the interface for the context needed for the HandlePruningPointProofRequests flow.
+type PruningPointProofRequestsContext interface {
+	Domain() domain.Domain
+}
+
+// HandlePruningPointProofRequests listens to appmessage.MsgRequestPruningPointProof messages and sends
+// the pruning point proof to the requesting peer.
+func HandlePruningPointProofRequests(context PruningPointProofRequestsContext, incomingRoute *router.Route,
+	outgoingRoute *router.Route, peer *peerpkg.Peer) error {
+
+	for {
+		_, err := incomingRoute.Dequeue()
+		if err != nil {
+			return err
+		}
+
+		log.Debugf("Got request for pruning point proof from %s", peer)
+
+		pruningPointProof, err := context.Domain().Consensus().BuildPruningPointProof()
+		if err != nil {
+			return err
+		}
+		pruningPointProofMessage := appmessage.DomainPruningPointProofToMsgPruningPointProof(pruningPointProof)
+		err = outgoingRoute.Enqueue(pruningPointProofMessage)
+		if err != nil {
+			return err
+		}
+
+		log.Debugf("Sent pruning point proof to %s", peer)
+	}
+}

app/protocol/flows/v4/blockrelay/handle_relay_invs.go

@@ -1,10 +1,9 @@
 package blockrelay
 
 import (
-	"time"
-
 	"github.com/kaspanet/kaspad/app/appmessage"
 	"github.com/kaspanet/kaspad/app/protocol/common"
+	"github.com/kaspanet/kaspad/app/protocol/flowcontext"
 	peerpkg "github.com/kaspanet/kaspad/app/protocol/peer"
 	"github.com/kaspanet/kaspad/app/protocol/protocolerrors"
 	"github.com/kaspanet/kaspad/domain"
@@ -13,7 +12,6 @@ import (
 	"github.com/kaspanet/kaspad/domain/consensus/utils/consensushashing"
 	"github.com/kaspanet/kaspad/infrastructure/config"
 	"github.com/kaspanet/kaspad/infrastructure/network/netadapter/router"
-	"github.com/kaspanet/kaspad/util/mstime"
 	"github.com/pkg/errors"
 )
 
@@ -26,16 +24,16 @@ var orphanResolutionRange uint32 = 5
 type RelayInvsContext interface {
 	Domain() domain.Domain
 	Config() *config.Config
-	OnNewBlock(block *externalapi.DomainBlock, blockInsertionResult *externalapi.BlockInsertionResult) error
+	OnNewBlock(block *externalapi.DomainBlock, virtualChangeSet *externalapi.VirtualChangeSet) error
+	OnVirtualChange(virtualChangeSet *externalapi.VirtualChangeSet) error
 	OnPruningPointUTXOSetOverride() error
-	SharedRequestedBlocks() *SharedRequestedBlocks
+	SharedRequestedBlocks() *flowcontext.SharedRequestedBlocks
 	Broadcast(message appmessage.Message) error
 	AddOrphan(orphanBlock *externalapi.DomainBlock)
 	GetOrphanRoots(orphanHash *externalapi.DomainHash) ([]*externalapi.DomainHash, bool, error)
 	IsOrphan(blockHash *externalapi.DomainHash) bool
 	IsIBDRunning() bool
-	TrySetIBDRunning(ibdPeer *peerpkg.Peer) bool
-	UnsetIBDRunning()
+	IsRecoverableError(err error) bool
 }
 
 type handleRelayInvsFlow struct {
@@ -57,7 +55,10 @@ func HandleRelayInvs(context RelayInvsContext, incomingRoute *router.Route, outg
 		peer:             peer,
 		invsQueue:        make([]*appmessage.MsgInvRelayBlock, 0),
 	}
-	return flow.start()
+	err := flow.start()
+	// Currently, HandleRelayInvs flow is the only place where IBD is triggered, so the channel can be closed now
+	close(peer.IBDRequestChannel())
+	return err
 }
 
 func (flow *handleRelayInvsFlow) start() error {
@@ -83,7 +84,18 @@ func (flow *handleRelayInvsFlow) start() error {
 			continue
 		}
 
+		isGenesisVirtualSelectedParent, err := flow.isGenesisVirtualSelectedParent()
+		if err != nil {
+			return err
+		}
+
 		if flow.IsOrphan(inv.Hash) {
+			if flow.Config().NetParams().DisallowDirectBlocksOnTopOfGenesis && !flow.Config().AllowSubmitBlockWhenNotSynced && isGenesisVirtualSelectedParent {
+				log.Infof("Cannot process orphan %s for a node with only the genesis block. The node needs to IBD "+
+					"to the recent pruning point before normal operation can resume.", inv.Hash)
+				continue
+			}
+
 			log.Debugf("Block %s is a known orphan. Requesting its missing ancestors", inv.Hash)
 			err := flow.AddOrphanRootsToQueue(inv.Hash)
 			if err != nil {
@@ -112,11 +124,14 @@ func (flow *handleRelayInvsFlow) start() error {
 		if err != nil {
 			return err
 		}
-		msTime := mstime.UnixMilliseconds(block.Header.TimeInMilliseconds())
-		time.Sleep(time.Until(msTime.ToNativeTime().Add(config.DelayDuration)))
+
+		if flow.Config().NetParams().DisallowDirectBlocksOnTopOfGenesis && !flow.Config().AllowSubmitBlockWhenNotSynced && !flow.Config().Devnet && flow.isChildOfGenesis(block) {
+			log.Infof("Cannot process %s because it's a direct child of genesis.", consensushashing.BlockHash(block))
+			continue
+		}
 
 		log.Debugf("Processing block %s", inv.Hash)
-		missingParents, blockInsertionResult, err := flow.processBlock(block)
+		missingParents, virtualChangeSet, err := flow.processBlock(block)
 		if err != nil {
 			if errors.Is(err, ruleerrors.ErrPrunedBlock) {
 				log.Infof("Ignoring pruned block %s", inv.Hash)
@@ -131,7 +146,7 @@ func (flow *handleRelayInvsFlow) start() error {
 		}
 		if len(missingParents) > 0 {
 			log.Debugf("Block %s is orphan and has missing parents: %s", inv.Hash, missingParents)
-			err := flow.processOrphan(block, missingParents)
+			err := flow.processOrphan(block)
 			if err != nil {
 				return err
 			}
@@ -144,7 +159,7 @@ func (flow *handleRelayInvsFlow) start() error {
 			return err
 		}
 		log.Infof("Accepted block %s via relay", inv.Hash)
-		err = flow.OnNewBlock(block, blockInsertionResult)
+		err = flow.OnNewBlock(block, virtualChangeSet)
 		if err != nil {
 			return err
 		}
@@ -181,14 +196,14 @@ func (flow *handleRelayInvsFlow) readInv() (*appmessage.MsgInvRelayBlock, error)
 }
 
 func (flow *handleRelayInvsFlow) requestBlock(requestHash *externalapi.DomainHash) (*externalapi.DomainBlock, bool, error) {
-	exists := flow.SharedRequestedBlocks().addIfNotExists(requestHash)
+	exists := flow.SharedRequestedBlocks().AddIfNotExists(requestHash)
 	if exists {
 		return nil, true, nil
 	}
 
 	// In case the function returns earlier than expected, we want to make sure flow.SharedRequestedBlocks() is
 	// clean from any pending blocks.
-	defer flow.SharedRequestedBlocks().remove(requestHash)
+	defer flow.SharedRequestedBlocks().Remove(requestHash)
 
 	getRelayBlocksMsg := appmessage.NewMsgRequestRelayBlocks([]*externalapi.DomainHash{requestHash})
 	err := flow.outgoingRoute.Enqueue(getRelayBlocksMsg)
@@ -231,9 +246,9 @@ func (flow *handleRelayInvsFlow) readMsgBlock() (msgBlock *appmessage.MsgBlock,
 	}
 }
 
-func (flow *handleRelayInvsFlow) processBlock(block *externalapi.DomainBlock) ([]*externalapi.DomainHash, *externalapi.BlockInsertionResult, error) {
+func (flow *handleRelayInvsFlow) processBlock(block *externalapi.DomainBlock) ([]*externalapi.DomainHash, *externalapi.VirtualChangeSet, error) {
 	blockHash := consensushashing.BlockHash(block)
-	blockInsertionResult, err := flow.Domain().Consensus().ValidateAndInsertBlock(block)
+	virtualChangeSet, err := flow.Domain().Consensus().ValidateAndInsertBlock(block, true)
 	if err != nil {
 		if !errors.As(err, &ruleerrors.RuleError{}) {
 			return nil, nil, errors.Wrapf(err, "failed to process block %s", blockHash)
@@ -246,7 +261,7 @@ func (flow *handleRelayInvsFlow) processBlock(block *externalapi.DomainBlock) ([
 		log.Warnf("Rejected block %s from %s: %s", blockHash, flow.peer, err)
 		return nil, nil, protocolerrors.Wrapf(true, err, "got invalid block %s from relay", blockHash)
 	}
-	return nil, blockInsertionResult, nil
+	return nil, virtualChangeSet, nil
 }
 
 func (flow *handleRelayInvsFlow) relayBlock(block *externalapi.DomainBlock) error {
@@ -254,7 +269,7 @@ func (flow *handleRelayInvsFlow) relayBlock(block *externalapi.DomainBlock) erro
 	return flow.Broadcast(appmessage.NewMsgInvBlock(blockHash))
 }
 
-func (flow *handleRelayInvsFlow) processOrphan(block *externalapi.DomainBlock, missingParents []*externalapi.DomainHash) error {
+func (flow *handleRelayInvsFlow) processOrphan(block *externalapi.DomainBlock) error {
 	blockHash := consensushashing.BlockHash(block)
 
 	// Return if the block has been orphaned from elsewhere already
@@ -269,6 +284,19 @@ func (flow *handleRelayInvsFlow) processOrphan(block *externalapi.DomainBlock, m
 		return err
 	}
 	if isBlockInOrphanResolutionRange {
+		if flow.Config().NetParams().DisallowDirectBlocksOnTopOfGenesis && !flow.Config().AllowSubmitBlockWhenNotSynced {
+			isGenesisVirtualSelectedParent, err := flow.isGenesisVirtualSelectedParent()
+			if err != nil {
+				return err
+			}
+
+			if isGenesisVirtualSelectedParent {
+				log.Infof("Cannot process orphan %s for a node with only the genesis block. The node needs to IBD "+
+					"to the recent pruning point before normal operation can resume.", blockHash)
+				return nil
+			}
+		}
+
 		log.Debugf("Block %s is within orphan resolution range. "+
 			"Adding it to the orphan set", blockHash)
 		flow.AddOrphan(block)
@@ -279,7 +307,28 @@ func (flow *handleRelayInvsFlow) processOrphan(block *externalapi.DomainBlock, m
 	// Start IBD unless we already are in IBD
 	log.Debugf("Block %s is out of orphan resolution range. "+
 		"Attempting to start IBD against it.", blockHash)
-	return flow.runIBDIfNotRunning(blockHash)
+
+	// Send the block to IBD flow via the IBDRequestChannel.
+	// Note that this is a non-blocking send, since if IBD is already running, there is no need to trigger it
+	select {
+	case flow.peer.IBDRequestChannel() <- block:
+	default:
+	}
+	return nil
+}
+
+func (flow *handleRelayInvsFlow) isGenesisVirtualSelectedParent() (bool, error) {
+	virtualSelectedParent, err := flow.Domain().Consensus().GetVirtualSelectedParent()
+	if err != nil {
+		return false, err
+	}
+
+	return virtualSelectedParent.Equal(flow.Config().NetParams().GenesisHash), nil
+}
+
+func (flow *handleRelayInvsFlow) isChildOfGenesis(block *externalapi.DomainBlock) bool {
+	parents := block.Header.DirectParents()
+	return len(parents) == 1 && parents[0].Equal(flow.Config().NetParams().GenesisHash)
 }
 
 // isBlockInOrphanResolutionRange finds out whether the given blockHash should be
@@ -288,8 +337,7 @@ func (flow *handleRelayInvsFlow) processOrphan(block *externalapi.DomainBlock, m
 // In the response, if we know none of the hashes, we should retrieve the given
 // blockHash via IBD. Otherwise, via unorphaning.
 func (flow *handleRelayInvsFlow) isBlockInOrphanResolutionRange(blockHash *externalapi.DomainHash) (bool, error) {
-	lowHash := flow.Config().ActiveNetParams.GenesisHash
-	err := flow.sendGetBlockLocator(lowHash, blockHash, orphanResolutionRange)
+	err := flow.sendGetBlockLocator(blockHash, orphanResolutionRange)
 	if err != nil {
 		return false, err
 	}

app/protocol/flows/v4/blockrelay/handle_request_block_locator.go

@@ -32,20 +32,19 @@ func HandleRequestBlockLocator(context RequestBlockLocatorContext, incomingRoute
 
 func (flow *handleRequestBlockLocatorFlow) start() error {
 	for {
-		lowHash, highHash, limit, err := flow.receiveGetBlockLocator()
+		highHash, limit, err := flow.receiveGetBlockLocator()
 		if err != nil {
 			return err
 		}
-		log.Debugf("Received getBlockLocator with lowHash: %s, highHash: %s, limit: %d",
-			lowHash, highHash, limit)
+		log.Debugf("Received getBlockLocator with highHash: %s, limit: %d", highHash, limit)
 
-		locator, err := flow.Domain().Consensus().CreateBlockLocator(lowHash, highHash, limit)
+		locator, err := flow.Domain().Consensus().CreateBlockLocatorFromPruningPoint(highHash, limit)
 		if err != nil || len(locator) == 0 {
 			if err != nil {
-				log.Debugf("Received error from CreateBlockLocator: %s", err)
+				log.Debugf("Received error from CreateBlockLocatorFromPruningPoint: %s", err)
 			}
 			return protocolerrors.Errorf(true, "couldn't build a block "+
-				"locator between blocks %s and %s", lowHash, highHash)
+				"locator between the pruning point and %s", highHash)
 		}
 
 		err = flow.sendBlockLocator(locator)
@@ -55,16 +54,15 @@ func (flow *handleRequestBlockLocatorFlow) start() error {
 	}
 }
 
-func (flow *handleRequestBlockLocatorFlow) receiveGetBlockLocator() (lowHash *externalapi.DomainHash,
-	highHash *externalapi.DomainHash, limit uint32, err error) {
+func (flow *handleRequestBlockLocatorFlow) receiveGetBlockLocator() (highHash *externalapi.DomainHash, limit uint32, err error) {
 
 	message, err := flow.incomingRoute.Dequeue()
 	if err != nil {
-		return nil, nil, 0, err
+		return nil, 0, err
 	}
 	msgGetBlockLocator := message.(*appmessage.MsgRequestBlockLocator)
 
-	return msgGetBlockLocator.LowHash, msgGetBlockLocator.HighHash, msgGetBlockLocator.Limit, nil
+	return msgGetBlockLocator.HighHash, msgGetBlockLocator.Limit, nil
 }
 
 func (flow *handleRequestBlockLocatorFlow) sendBlockLocator(locator externalapi.BlockLocator) error {

app/protocol/flows/v4/blockrelay/handle_request_headers.go

@@ -12,26 +12,26 @@ import (
 
 const ibdBatchSize = router.DefaultMaxMessages
 
-// RequestIBDBlocksContext is the interface for the context needed for the HandleRequestHeaders flow.
-type RequestIBDBlocksContext interface {
+// RequestHeadersContext is the interface for the context needed for the HandleRequestHeaders flow.
+type RequestHeadersContext interface {
 	Domain() domain.Domain
 }
 
 type handleRequestHeadersFlow struct {
-	RequestIBDBlocksContext
+	RequestHeadersContext
 	incomingRoute, outgoingRoute *router.Route
 	peer                         *peer.Peer
 }
 
 // HandleRequestHeaders handles RequestHeaders messages
-func HandleRequestHeaders(context RequestIBDBlocksContext, incomingRoute *router.Route,
+func HandleRequestHeaders(context RequestHeadersContext, incomingRoute *router.Route,
 	outgoingRoute *router.Route, peer *peer.Peer) error {
 
 	flow := &handleRequestHeadersFlow{
-		RequestIBDBlocksContext: context,
-		incomingRoute:           incomingRoute,
-		outgoingRoute:           outgoingRoute,
-		peer:                    peer,
+		RequestHeadersContext: context,
+		incomingRoute:         incomingRoute,
+		outgoingRoute:         outgoingRoute,
+		peer:                  peer,
 	}
 	return flow.start()
 }
@@ -49,8 +49,9 @@ func (flow *handleRequestHeadersFlow) start() error {
 
 			// GetHashesBetween is a relatively heavy operation so we limit it
 			// in order to avoid locking the consensus for too long
-			const maxBlueScoreDifference = 1 << 10
-			blockHashes, _, err := flow.Domain().Consensus().GetHashesBetween(lowHash, highHash, maxBlueScoreDifference)
+			// maxBlocks MUST be >= MergeSetSizeLimit + 1
+			const maxBlocks = 1 << 10
+			blockHashes, _, err := flow.Domain().Consensus().GetHashesBetween(lowHash, highHash, maxBlocks)
 			if err != nil {
 				return err
 			}

app/protocol/flows/v4/blockrelay/handle_request_pruning_point_utxo_set.go

@@ -0,0 +1,140 @@
+package blockrelay
+
+import (
+	"errors"
+	"github.com/kaspanet/kaspad/app/appmessage"
+	"github.com/kaspanet/kaspad/app/protocol/common"
+	"github.com/kaspanet/kaspad/app/protocol/protocolerrors"
+	"github.com/kaspanet/kaspad/domain"
+	"github.com/kaspanet/kaspad/domain/consensus/model/externalapi"
+	"github.com/kaspanet/kaspad/domain/consensus/ruleerrors"
+	"github.com/kaspanet/kaspad/infrastructure/logger"
+	"github.com/kaspanet/kaspad/infrastructure/network/netadapter/router"
+)
+
+// HandleRequestPruningPointUTXOSetContext is the interface for the context needed for the HandleRequestPruningPointUTXOSet flow.
+type HandleRequestPruningPointUTXOSetContext interface {
+	Domain() domain.Domain
+}
+
+type handleRequestPruningPointUTXOSetFlow struct {
+	HandleRequestPruningPointUTXOSetContext
+	incomingRoute, outgoingRoute *router.Route
+}
+
+// HandleRequestPruningPointUTXOSet listens to appmessage.MsgRequestPruningPointUTXOSet messages and sends
+// the pruning point UTXO set and block body.
+func HandleRequestPruningPointUTXOSet(context HandleRequestPruningPointUTXOSetContext, incomingRoute,
+	outgoingRoute *router.Route) error {
+
+	flow := &handleRequestPruningPointUTXOSetFlow{
+		HandleRequestPruningPointUTXOSetContext: context,
+		incomingRoute:                           incomingRoute,
+		outgoingRoute:                           outgoingRoute,
+	}
+
+	return flow.start()
+}
+
+func (flow *handleRequestPruningPointUTXOSetFlow) start() error {
+	for {
+		msgRequestPruningPointUTXOSet, err := flow.waitForRequestPruningPointUTXOSetMessages()
+		if err != nil {
+			return err
+		}
+
+		err = flow.handleRequestPruningPointUTXOSetMessage(msgRequestPruningPointUTXOSet)
+		if err != nil {
+			return err
+		}
+	}
+}
+
+func (flow *handleRequestPruningPointUTXOSetFlow) handleRequestPruningPointUTXOSetMessage(
+	msgRequestPruningPointUTXOSet *appmessage.MsgRequestPruningPointUTXOSet) error {
+
+	onEnd := logger.LogAndMeasureExecutionTime(log, "handleRequestPruningPointUTXOSetFlow")
+	defer onEnd()
+
+	log.Debugf("Got request for pruning point UTXO set")
+
+	return flow.sendPruningPointUTXOSet(msgRequestPruningPointUTXOSet)
+}
+
+func (flow *handleRequestPruningPointUTXOSetFlow) waitForRequestPruningPointUTXOSetMessages() (
+	*appmessage.MsgRequestPruningPointUTXOSet, error) {
+
+	message, err := flow.incomingRoute.Dequeue()
+	if err != nil {
+		return nil, err
+	}
+	msgRequestPruningPointUTXOSet, ok := message.(*appmessage.MsgRequestPruningPointUTXOSet)
+	if !ok {
+		// TODO: Change to shouldBan: true once we fix the bug of getting redundant messages
+		return nil, protocolerrors.Errorf(false, "received unexpected message type. "+
+			"expected: %s, got: %s", appmessage.CmdRequestPruningPointUTXOSet, message.Command())
+	}
+	return msgRequestPruningPointUTXOSet, nil
+}
+
+func (flow *handleRequestPruningPointUTXOSetFlow) sendPruningPointUTXOSet(
+	msgRequestPruningPointUTXOSet *appmessage.MsgRequestPruningPointUTXOSet) error {
+
+	// Send the UTXO set in `step`-sized chunks
+	const step = 1000
+	var fromOutpoint *externalapi.DomainOutpoint
+	chunksSent := 0
+	for {
+		pruningPointUTXOs, err := flow.Domain().Consensus().GetPruningPointUTXOs(
+			msgRequestPruningPointUTXOSet.PruningPointHash, fromOutpoint, step)
+		if err != nil {
+			if errors.Is(err, ruleerrors.ErrWrongPruningPointHash) {
+				return flow.outgoingRoute.Enqueue(appmessage.NewMsgUnexpectedPruningPoint())
+			}
+		}
+
+		log.Debugf("Retrieved %d UTXOs for pruning block %s",
+			len(pruningPointUTXOs), msgRequestPruningPointUTXOSet.PruningPointHash)
+
+		outpointAndUTXOEntryPairs :=
+			appmessage.DomainOutpointAndUTXOEntryPairsToOutpointAndUTXOEntryPairs(pruningPointUTXOs)
+		err = flow.outgoingRoute.Enqueue(appmessage.NewMsgPruningPointUTXOSetChunk(outpointAndUTXOEntryPairs))
+		if err != nil {
+			return err
+		}
+
+		finished := len(pruningPointUTXOs) < step
+		if finished && chunksSent%ibdBatchSize != 0 {
+			log.Debugf("Finished sending UTXOs for pruning block %s",
+				msgRequestPruningPointUTXOSet.PruningPointHash)
+
+			return flow.outgoingRoute.Enqueue(appmessage.NewMsgDonePruningPointUTXOSetChunks())
+		}
+
+		if len(pruningPointUTXOs) > 0 {
+			fromOutpoint = pruningPointUTXOs[len(pruningPointUTXOs)-1].Outpoint
+		}
+		chunksSent++
+
+		// Wait for the peer to request more chunks every `ibdBatchSize` chunks
+		if chunksSent%ibdBatchSize == 0 {
+			message, err := flow.incomingRoute.DequeueWithTimeout(common.DefaultTimeout)
+			if err != nil {
+				return err
+			}
+			_, ok := message.(*appmessage.MsgRequestNextPruningPointUTXOSetChunk)
+			if !ok {
+				// TODO: Change to shouldBan: true once we fix the bug of getting redundant messages
+				return protocolerrors.Errorf(false, "received unexpected message type. "+
+					"expected: %s, got: %s", appmessage.CmdRequestNextPruningPointUTXOSetChunk, message.Command())
+			}
+
+			if finished {
+				log.Debugf("Finished sending UTXOs for pruning block %s",
+					msgRequestPruningPointUTXOSet.PruningPointHash)
+
+				return flow.outgoingRoute.Enqueue(appmessage.NewMsgDonePruningPointUTXOSetChunks())
+			}
+		}
+	}
+}

app/protocol/flows/v4/blockrelay/ibd.go

@@ -1,100 +1,180 @@
 package blockrelay
 
 import (
-	"fmt"
-	"time"
-
-	"github.com/kaspanet/kaspad/infrastructure/logger"
-
-	"github.com/kaspanet/kaspad/domain/consensus/model"
-
 	"github.com/kaspanet/kaspad/app/appmessage"
 	"github.com/kaspanet/kaspad/app/protocol/common"
+	peerpkg "github.com/kaspanet/kaspad/app/protocol/peer"
 	"github.com/kaspanet/kaspad/app/protocol/protocolerrors"
+	"github.com/kaspanet/kaspad/domain"
+	"github.com/kaspanet/kaspad/domain/consensus/model"
 	"github.com/kaspanet/kaspad/domain/consensus/model/externalapi"
 	"github.com/kaspanet/kaspad/domain/consensus/ruleerrors"
 	"github.com/kaspanet/kaspad/domain/consensus/utils/consensushashing"
+	"github.com/kaspanet/kaspad/infrastructure/config"
+	"github.com/kaspanet/kaspad/infrastructure/logger"
+	"github.com/kaspanet/kaspad/infrastructure/network/netadapter/router"
 	"github.com/pkg/errors"
+	"time"
 )
 
-func (flow *handleRelayInvsFlow) runIBDIfNotRunning(highHash *externalapi.DomainHash) error {
+// IBDContext is the interface for the context needed for the HandleIBD flow.
+type IBDContext interface {
+	Domain() domain.Domain
+	Config() *config.Config
+	OnNewBlock(block *externalapi.DomainBlock, virtualChangeSet *externalapi.VirtualChangeSet) error
+	OnVirtualChange(virtualChangeSet *externalapi.VirtualChangeSet) error
+	OnPruningPointUTXOSetOverride() error
+	IsIBDRunning() bool
+	TrySetIBDRunning(ibdPeer *peerpkg.Peer) bool
+	UnsetIBDRunning()
+	IsRecoverableError(err error) bool
+}
+
+type handleIBDFlow struct {
+	IBDContext
+	incomingRoute, outgoingRoute *router.Route
+	peer                         *peerpkg.Peer
+}
+
+// HandleIBD handles IBD
+func HandleIBD(context IBDContext, incomingRoute *router.Route, outgoingRoute *router.Route,
+	peer *peerpkg.Peer) error {
+
+	flow := &handleIBDFlow{
+		IBDContext:    context,
+		incomingRoute: incomingRoute,
+		outgoingRoute: outgoingRoute,
+		peer:          peer,
+	}
+	return flow.start()
+}
+
+func (flow *handleIBDFlow) start() error {
+	for {
+		// Wait for IBD requests triggered by other flows
+		block, ok := <-flow.peer.IBDRequestChannel()
+		if !ok {
+			return nil
+		}
+		err := flow.runIBDIfNotRunning(block)
+		if err != nil {
+			return err
+		}
+	}
+}
+
+func (flow *handleIBDFlow) runIBDIfNotRunning(block *externalapi.DomainBlock) error {
 	wasIBDNotRunning := flow.TrySetIBDRunning(flow.peer)
 	if !wasIBDNotRunning {
 		log.Debugf("IBD is already running")
 		return nil
 	}
-	defer flow.UnsetIBDRunning()
 
-	log.Debugf("IBD started with peer %s and highHash %s", flow.peer, highHash)
+	isFinishedSuccessfully := false
+	defer func() {
+		flow.UnsetIBDRunning()
+		flow.logIBDFinished(isFinishedSuccessfully)
+	}()
 
-	log.Debugf("Syncing headers up to %s", highHash)
-	headersSynced, err := flow.syncHeaders(highHash)
+	highHash := consensushashing.BlockHash(block)
+	log.Criticalf("IBD started with peer %s and highHash %s", flow.peer, highHash)
+	log.Criticalf("Syncing blocks up to %s", highHash)
+	log.Criticalf("Trying to find highest shared chain block with peer %s with high hash %s", flow.peer, highHash)
+	highestSharedBlockHash, highestSharedBlockFound, err := flow.findHighestSharedBlockHash(highHash)
 	if err != nil {
 		return err
 	}
-	if !headersSynced {
-		log.Debugf("Aborting IBD because the headers failed to sync")
-		return nil
-	}
-	log.Debugf("Finished syncing headers up to %s", highHash)
+	log.Criticalf("Found highest shared chain block %s with peer %s", highestSharedBlockHash, flow.peer)
+	if highestSharedBlockFound {
+		checkpoint, err := externalapi.NewDomainHashFromString("cdae6724abde94eebbc5cd2d8aa0861a39e5661526771c027ef2ebce32f76bbe")
+		if err != nil {
+			return err
+		}
 
-	log.Debugf("Syncing the current pruning point UTXO set")
-	syncedPruningPointUTXOSetSuccessfully, err := flow.syncPruningPointUTXOSet()
+		info, err := flow.Domain().Consensus().GetBlockInfo(checkpoint)
+		if err != nil {
+			return err
+		}
+
+		if info.Exists {
+			isInSelectedParentChainOf, err := flow.Domain().Consensus().IsInSelectedParentChainOf(checkpoint, highestSharedBlockHash)
+			if err != nil {
+				return err
+			}
+
+			if !isInSelectedParentChainOf {
+				log.Criticalf("Stopped IBD because the checkpoint %s is not in the selected chain of %s", checkpoint, highestSharedBlockHash)
+				return nil
+			}
+		}
+	}
+
+	shouldDownloadHeadersProof, shouldSync, err := flow.shouldSyncAndShouldDownloadHeadersProof(block, highestSharedBlockFound)
 	if err != nil {
 		return err
 	}
-	if !syncedPruningPointUTXOSetSuccessfully {
-		log.Debugf("Aborting IBD because the pruning point UTXO set failed to sync")
+
+	if !shouldSync {
 		return nil
 	}
-	log.Debugf("Finished syncing the current pruning point UTXO set")
 
-	log.Debugf("Downloading block bodies up to %s", highHash)
+	if shouldDownloadHeadersProof {
+		log.Infof("Starting IBD with headers proof")
+		err := flow.ibdWithHeadersProof(highHash, block.Header.DAAScore())
+		if err != nil {
+			return err
+		}
+	} else {
+		if flow.Config().NetParams().DisallowDirectBlocksOnTopOfGenesis && !flow.Config().AllowSubmitBlockWhenNotSynced {
+			isGenesisVirtualSelectedParent, err := flow.isGenesisVirtualSelectedParent()
+			if err != nil {
+				return err
+			}
+
+			if isGenesisVirtualSelectedParent {
+				log.Infof("Cannot IBD to %s because it won't change the pruning point. The node needs to IBD "+
+					"to the recent pruning point before normal operation can resume.", highHash)
+				return nil
+			}
+		}
+
+		err = flow.syncPruningPointFutureHeaders(flow.Domain().Consensus(), highestSharedBlockHash, highHash, block.Header.DAAScore())
+		if err != nil {
+			return err
+		}
+	}
+
 	err = flow.syncMissingBlockBodies(highHash)
 	if err != nil {
 		return err
 	}
-	log.Debugf("Finished downloading block bodies up to %s", highHash)
 
+	log.Debugf("Finished syncing blocks up to %s", highHash)
+	isFinishedSuccessfully = true
 	return nil
 }
 
-// syncHeaders attempts to sync headers from the peer. This method may fail
-// because the peer and us have conflicting pruning points. In that case we
-// return (false, nil) so that we may stop IBD gracefully.
-func (flow *handleRelayInvsFlow) syncHeaders(highHash *externalapi.DomainHash) (bool, error) {
-	log.Debugf("Trying to find highest shared chain block with peer %s with high hash %s", flow.peer, highHash)
-	highestSharedBlockHash, highestSharedBlockFound, err := flow.findHighestSharedBlockHash(highHash)
-	if err != nil {
-		return false, err
-	}
-	if !highestSharedBlockFound {
-		return false, nil
-	}
-	log.Debugf("Found highest shared chain block %s with peer %s", highestSharedBlockHash, flow.peer)
-
-	err = flow.downloadHeaders(highestSharedBlockHash, highHash)
+func (flow *handleIBDFlow) isGenesisVirtualSelectedParent() (bool, error) {
+	virtualSelectedParent, err := flow.Domain().Consensus().GetVirtualSelectedParent()
 	if err != nil {
 		return false, err
 	}
 
-	// If the highHash has not been received, the peer is misbehaving
-	highHashBlockInfo, err := flow.Domain().Consensus().GetBlockInfo(highHash)
-	if err != nil {
-		return false, err
+	return virtualSelectedParent.Equal(flow.Config().NetParams().GenesisHash), nil
+}
+
+func (flow *handleIBDFlow) logIBDFinished(isFinishedSuccessfully bool) {
+	successString := "successfully"
+	if !isFinishedSuccessfully {
+		successString = "(interrupted)"
 	}
-	if !highHashBlockInfo.Exists {
-		return false, protocolerrors.Errorf(true, "did not receive "+
-			"highHash header %s from peer %s during header download", highHash, flow.peer)
-	}
-	log.Debugf("Headers downloaded from peer %s", flow.peer)
-	return true, nil
+	log.Infof("IBD finished %s", successString)
 }
 
 // findHighestSharedBlock attempts to find the highest shared block between the peer
 // and this node. This method may fail because the peer and us have conflicting pruning
 // points. In that case we return (nil, false, nil) so that we may stop IBD gracefully.
-func (flow *handleRelayInvsFlow) findHighestSharedBlockHash(
+func (flow *handleIBDFlow) findHighestSharedBlockHash(
 	targetHash *externalapi.DomainHash) (*externalapi.DomainHash, bool, error) {
 
 	log.Debugf("Sending a blockLocator to %s between pruning point and headers selected tip", flow.peer)
@@ -137,7 +217,7 @@ func (flow *handleRelayInvsFlow) findHighestSharedBlockHash(
 	}
 }
 
-func (flow *handleRelayInvsFlow) nextBlockLocator(lowHash, highHash *externalapi.DomainHash) (externalapi.BlockLocator, error) {
+func (flow *handleIBDFlow) nextBlockLocator(lowHash, highHash *externalapi.DomainHash) (externalapi.BlockLocator, error) {
 	log.Debugf("Sending a blockLocator to %s between %s and %s", flow.peer, lowHash, highHash)
 	blockLocator, err := flow.Domain().Consensus().CreateHeadersSelectedChainBlockLocator(lowHash, highHash)
 	if err != nil {
@@ -155,7 +235,7 @@ func (flow *handleRelayInvsFlow) nextBlockLocator(lowHash, highHash *externalapi
 	return blockLocator, nil
 }
 
-func (flow *handleRelayInvsFlow) findHighestHashIndex(
+func (flow *handleIBDFlow) findHighestHashIndex(
 	highestHash *externalapi.DomainHash, blockLocator externalapi.BlockLocator) (int, error) {
 
 	highestHashIndex := 0
@@ -180,7 +260,7 @@ func (flow *handleRelayInvsFlow) findHighestHashIndex(
 // fetchHighestHash attempts to fetch the highest hash the peer knows amongst the given
 // blockLocator. This method may fail because the peer and us have conflicting pruning
 // points. In that case we return (nil, false, nil) so that we may stop IBD gracefully.
-func (flow *handleRelayInvsFlow) fetchHighestHash(
+func (flow *handleIBDFlow) fetchHighestHash(
 	targetHash *externalapi.DomainHash, blockLocator externalapi.BlockLocator) (*externalapi.DomainHash, bool, error) {
 
 	ibdBlockLocatorMessage := appmessage.NewMsgIBDBlockLocator(targetHash, blockLocator)
@@ -188,7 +268,7 @@ func (flow *handleRelayInvsFlow) fetchHighestHash(
 	if err != nil {
 		return nil, false, err
 	}
-	message, err := flow.dequeueIncomingMessageAndSkipInvs(common.DefaultTimeout)
+	message, err := flow.incomingRoute.DequeueWithTimeout(common.DefaultTimeout)
 	if err != nil {
 		return nil, false, err
 	}
@@ -208,20 +288,28 @@ func (flow *handleRelayInvsFlow) fetchHighestHash(
 	}
 }
 
-func (flow *handleRelayInvsFlow) downloadHeaders(highestSharedBlockHash *externalapi.DomainHash,
-	highHash *externalapi.DomainHash) error {
+func (flow *handleIBDFlow) syncPruningPointFutureHeaders(consensus externalapi.Consensus, highestSharedBlockHash *externalapi.DomainHash,
+	highHash *externalapi.DomainHash, highBlockDAAScore uint64) error {
+
+	log.Infof("Downloading headers from %s", flow.peer)
 
 	err := flow.sendRequestHeaders(highestSharedBlockHash, highHash)
 	if err != nil {
 		return err
 	}
 
-	// Keep a short queue of blockHeadersMessages so that there's
+	highestSharedBlockHeader, err := consensus.GetBlockHeader(highestSharedBlockHash)
+	if err != nil {
+		return err
+	}
+	progressReporter := newIBDProgressReporter(highestSharedBlockHeader.DAAScore(), highBlockDAAScore, "block headers")
+
+	// Keep a short queue of BlockHeadersMessages so that there's
 	// never a moment when the node is not validating and inserting
 	// headers
 	blockHeadersMessageChan := make(chan *appmessage.BlockHeadersMessage, 2)
 	errChan := make(chan error)
-	spawn("handleRelayInvsFlow-downloadHeaders", func() {
+	spawn("handleRelayInvsFlow-syncPruningPointFutureHeaders", func() {
 		for {
 			blockHeadersMessage, doneIBD, err := flow.receiveHeaders()
 			if err != nil {
@@ -245,31 +333,43 @@ func (flow *handleRelayInvsFlow) downloadHeaders(highestSharedBlockHash *externa
 
 	for {
 		select {
-		case blockHeadersMessage, ok := <-blockHeadersMessageChan:
+		case ibdBlocksMessage, ok := <-blockHeadersMessageChan:
 			if !ok {
+				// If the highHash has not been received, the peer is misbehaving
+				highHashBlockInfo, err := consensus.GetBlockInfo(highHash)
+				if err != nil {
+					return err
+				}
+				if !highHashBlockInfo.Exists {
+					return protocolerrors.Errorf(true, "did not receive "+
+						"highHash block %s from peer %s during block download", highHash, flow.peer)
+				}
 				return nil
 			}
-			for _, header := range blockHeadersMessage.BlockHeaders {
-				err = flow.processHeader(header)
+			for _, header := range ibdBlocksMessage.BlockHeaders {
+				_, err := flow.processHeader(consensus, header)
 				if err != nil {
 					return err
 				}
 			}
+
+			lastReceivedHeader := ibdBlocksMessage.BlockHeaders[len(ibdBlocksMessage.BlockHeaders)-1]
+			progressReporter.reportProgress(len(ibdBlocksMessage.BlockHeaders), lastReceivedHeader.DAAScore)
 		case err := <-errChan:
 			return err
 		}
 	}
 }
 
-func (flow *handleRelayInvsFlow) sendRequestHeaders(highestSharedBlockHash *externalapi.DomainHash,
+func (flow *handleIBDFlow) sendRequestHeaders(highestSharedBlockHash *externalapi.DomainHash,
 	peerSelectedTipHash *externalapi.DomainHash) error {
 
 	msgGetBlockInvs := appmessage.NewMsgRequstHeaders(highestSharedBlockHash, peerSelectedTipHash)
 	return flow.outgoingRoute.Enqueue(msgGetBlockInvs)
 }
 
-func (flow *handleRelayInvsFlow) receiveHeaders() (msgIBDBlock *appmessage.BlockHeadersMessage, doneIBD bool, err error) {
-	message, err := flow.dequeueIncomingMessageAndSkipInvs(common.DefaultTimeout)
+func (flow *handleIBDFlow) receiveHeaders() (msgIBDBlock *appmessage.BlockHeadersMessage, doneHeaders bool, err error) {
+	message, err := flow.incomingRoute.DequeueWithTimeout(common.DefaultTimeout)
 	if err != nil {
 		return nil, false, err
 	}
@@ -281,11 +381,14 @@ func (flow *handleRelayInvsFlow) receiveHeaders() (msgIBDBlock *appmessage.Block
 	default:
 		return nil, false,
 			protocolerrors.Errorf(true, "received unexpected message type. "+
-				"expected: %s or %s, got: %s", appmessage.CmdHeader, appmessage.CmdDoneHeaders, message.Command())
+				"expected: %s or %s, got: %s",
+				appmessage.CmdBlockHeaders,
+				appmessage.CmdDoneHeaders,
+				message.Command())
 	}
 }
 
-func (flow *handleRelayInvsFlow) processHeader(msgBlockHeader *appmessage.MsgBlockHeader) error {
+func (flow *handleIBDFlow) processHeader(consensus externalapi.Consensus, msgBlockHeader *appmessage.MsgBlockHeader) (bool, error) {
 	header := appmessage.BlockHeaderToDomainBlockHeader(msgBlockHeader)
 	block := &externalapi.DomainBlock{
 		Header:       header,
@@ -293,154 +396,66 @@ func (flow *handleRelayInvsFlow) processHeader(msgBlockHeader *appmessage.MsgBlo
 	}
 
 	blockHash := consensushashing.BlockHash(block)
-	blockInfo, err := flow.Domain().Consensus().GetBlockInfo(blockHash)
+	blockInfo, err := consensus.GetBlockInfo(blockHash)
 	if err != nil {
-		return err
+		return false, err
 	}
 	if blockInfo.Exists {
 		log.Debugf("Block header %s is already in the DAG. Skipping...", blockHash)
-		return nil
+		return false, nil
 	}
-	_, err = flow.Domain().Consensus().ValidateAndInsertBlock(block)
+	_, err = consensus.ValidateAndInsertBlock(block, false)
 	if err != nil {
 		if !errors.As(err, &ruleerrors.RuleError{}) {
-			return errors.Wrapf(err, "failed to process header %s during IBD", blockHash)
+			return false, errors.Wrapf(err, "failed to process header %s during IBD", blockHash)
 		}
 
 		if errors.Is(err, ruleerrors.ErrDuplicateBlock) {
 			log.Debugf("Skipping block header %s as it is a duplicate", blockHash)
 		} else {
 			log.Infof("Rejected block header %s from %s during IBD: %s", blockHash, flow.peer, err)
-			return protocolerrors.Wrapf(true, err, "got invalid block header %s during IBD", blockHash)
+			return false, protocolerrors.Wrapf(true, err, "got invalid block header %s during IBD", blockHash)
 		}
 	}
+	return true, nil
+}
 
+func (flow *handleIBDFlow) validatePruningPointFutureHeaderTimestamps() error {
+	headerSelectedTipHash, err := flow.Domain().StagingConsensus().GetHeadersSelectedTip()
+	if err != nil {
+		return err
+	}
+	headerSelectedTipHeader, err := flow.Domain().StagingConsensus().GetBlockHeader(headerSelectedTipHash)
+	if err != nil {
+		return err
+	}
+	headerSelectedTipTimestamp := headerSelectedTipHeader.TimeInMilliseconds()
+
+	currentSelectedTipHash, err := flow.Domain().Consensus().GetHeadersSelectedTip()
+	if err != nil {
+		return err
+	}
+	currentSelectedTipHeader, err := flow.Domain().Consensus().GetBlockHeader(currentSelectedTipHash)
+	if err != nil {
+		return err
+	}
+	currentSelectedTipTimestamp := currentSelectedTipHeader.TimeInMilliseconds()
+
+	if headerSelectedTipTimestamp < currentSelectedTipTimestamp {
+		return protocolerrors.Errorf(false, "the timestamp of the candidate selected "+
+			"tip is smaller than the current selected tip")
+	}
+
+	minTimestampDifferenceInMilliseconds := (10 * time.Minute).Milliseconds()
+	if headerSelectedTipTimestamp-currentSelectedTipTimestamp < minTimestampDifferenceInMilliseconds {
+		return protocolerrors.Errorf(false, "difference between the timestamps of "+
+			"the current pruning point and the candidate pruning point is too small. Aborting IBD...")
+	}
 	return nil
 }
 
-func (flow *handleRelayInvsFlow) syncPruningPointUTXOSet() (bool, error) {
-	log.Debugf("Checking if a new pruning point is available")
-	err := flow.outgoingRoute.Enqueue(appmessage.NewMsgRequestPruningPointHashMessage())
-	if err != nil {
-		return false, err
-	}
-	message, err := flow.dequeueIncomingMessageAndSkipInvs(common.DefaultTimeout)
-	if err != nil {
-		return false, err
-	}
-	msgPruningPointHash, ok := message.(*appmessage.MsgPruningPointHashMessage)
-	if !ok {
-		return false, protocolerrors.Errorf(true, "received unexpected message type. "+
-			"expected: %s, got: %s", appmessage.CmdPruningPointHash, message.Command())
-	}
-
-	blockInfo, err := flow.Domain().Consensus().GetBlockInfo(msgPruningPointHash.Hash)
-	if err != nil {
-		return false, err
-	}
-
-	if !blockInfo.Exists {
-		return false, errors.Errorf("The pruning point header is missing")
-	}
-
-	if blockInfo.BlockStatus != externalapi.StatusHeaderOnly {
-		log.Debugf("Already has the block data of the new suggested pruning point %s", msgPruningPointHash.Hash)
-		return true, nil
-	}
-
-	log.Infof("Checking if the suggested pruning point %s is compatible to the node DAG", msgPruningPointHash.Hash)
-	isValid, err := flow.Domain().Consensus().IsValidPruningPoint(msgPruningPointHash.Hash)
-	if err != nil {
-		return false, err
-	}
-
-	if !isValid {
-		log.Infof("The suggested pruning point %s is incompatible to this node DAG, so stopping IBD with this"+
-			" peer", msgPruningPointHash.Hash)
-		return false, nil
-	}
-
-	log.Info("Fetching the pruning point UTXO set")
-	succeed, err := flow.fetchMissingUTXOSet(msgPruningPointHash.Hash)
-	if err != nil {
-		return false, err
-	}
-
-	if !succeed {
-		log.Infof("Couldn't successfully fetch the pruning point UTXO set. Stopping IBD.")
-		return false, nil
-	}
-
-	log.Info("Fetched the new pruning point UTXO set")
-	return true, nil
-}
-
-func (flow *handleRelayInvsFlow) fetchMissingUTXOSet(pruningPointHash *externalapi.DomainHash) (succeed bool, err error) {
-	defer func() {
-		err := flow.Domain().Consensus().ClearImportedPruningPointData()
-		if err != nil {
-			panic(fmt.Sprintf("failed to clear imported pruning point data: %s", err))
-		}
-	}()
-
-	err = flow.outgoingRoute.Enqueue(appmessage.NewMsgRequestPruningPointUTXOSetAndBlock(pruningPointHash))
-	if err != nil {
-		return false, err
-	}
-
-	block, err := flow.receivePruningPointBlock()
-	if err != nil {
-		return false, err
-	}
-
-	receivedAll, err := flow.receiveAndInsertPruningPointUTXOSet(pruningPointHash)
-	if err != nil {
-		return false, err
-	}
-	if !receivedAll {
-		return false, nil
-	}
-
-	err = flow.Domain().Consensus().ValidateAndInsertImportedPruningPoint(block)
-	if err != nil {
-		// TODO: Find a better way to deal with finality conflicts.
-		if errors.Is(err, ruleerrors.ErrSuggestedPruningViolatesFinality) {
-			return false, nil
-		}
-		return false, protocolerrors.ConvertToBanningProtocolErrorIfRuleError(err, "error with pruning point UTXO set")
-	}
-
-	err = flow.OnPruningPointUTXOSetOverride()
-	if err != nil {
-		return false, err
-	}
-
-	return true, nil
-}
-
-func (flow *handleRelayInvsFlow) receivePruningPointBlock() (*externalapi.DomainBlock, error) {
-	onEnd := logger.LogAndMeasureExecutionTime(log, "receivePruningPointBlock")
-	defer onEnd()
-
-	message, err := flow.dequeueIncomingMessageAndSkipInvs(common.DefaultTimeout)
-	if err != nil {
-		return nil, err
-	}
-
-	ibdBlockMessage, ok := message.(*appmessage.MsgIBDBlock)
-	if !ok {
-		return nil, protocolerrors.Errorf(true, "received unexpected message type. "+
-			"expected: %s, got: %s", appmessage.CmdIBDBlock, message.Command())
-	}
-	block := appmessage.MsgBlockToDomainBlock(ibdBlockMessage.MsgBlock)
-
-	log.Debugf("Received pruning point block %s", consensushashing.BlockHash(block))
-
-	return block, nil
-}
-
-func (flow *handleRelayInvsFlow) receiveAndInsertPruningPointUTXOSet(
-	pruningPointHash *externalapi.DomainHash) (bool, error) {
+func (flow *handleIBDFlow) receiveAndInsertPruningPointUTXOSet(
+	consensus externalapi.Consensus, pruningPointHash *externalapi.DomainHash) (bool, error) {
 
 	onEnd := logger.LogAndMeasureExecutionTime(log, "receiveAndInsertPruningPointUTXOSet")
 	defer onEnd()
@@ -448,7 +463,7 @@ func (flow *handleRelayInvsFlow) receiveAndInsertPruningPointUTXOSet(
 	receivedChunkCount := 0
 	receivedUTXOCount := 0
 	for {
-		message, err := flow.dequeueIncomingMessageAndSkipInvs(common.DefaultTimeout)
+		message, err := flow.incomingRoute.DequeueWithTimeout(common.DefaultTimeout)
 		if err != nil {
 			return false, err
 		}
@@ -459,7 +474,7 @@ func (flow *handleRelayInvsFlow) receiveAndInsertPruningPointUTXOSet(
 			domainOutpointAndUTXOEntryPairs :=
 				appmessage.OutpointAndUTXOEntryPairsToDomainOutpointAndUTXOEntryPairs(message.OutpointAndUTXOEntryPairs)
 
-			err := flow.Domain().Consensus().AppendImportedPruningPointUTXOs(domainOutpointAndUTXOEntryPairs)
+			err := consensus.AppendImportedPruningPointUTXOs(domainOutpointAndUTXOEntryPairs)
 			if err != nil {
 				return false, err
 			}
@@ -494,7 +509,7 @@ func (flow *handleRelayInvsFlow) receiveAndInsertPruningPointUTXOSet(
 	}
 }
 
-func (flow *handleRelayInvsFlow) syncMissingBlockBodies(highHash *externalapi.DomainHash) error {
+func (flow *handleIBDFlow) syncMissingBlockBodies(highHash *externalapi.DomainHash) error {
 	hashes, err := flow.Domain().Consensus().GetMissingBlockBodyHashes(highHash)
 	if err != nil {
 		return err
@@ -507,6 +522,17 @@ func (flow *handleRelayInvsFlow) syncMissingBlockBodies(highHash *externalapi.Do
 		return nil
 	}
 
+	lowBlockHeader, err := flow.Domain().Consensus().GetBlockHeader(hashes[0])
+	if err != nil {
+		return err
+	}
+	highBlockHeader, err := flow.Domain().Consensus().GetBlockHeader(hashes[len(hashes)-1])
+	if err != nil {
+		return err
+	}
+	progressReporter := newIBDProgressReporter(lowBlockHeader.DAAScore(), highBlockHeader.DAAScore(), "blocks")
+	highestProcessedDAAScore := lowBlockHeader.DAAScore()
+
 	for offset := 0; offset < len(hashes); offset += ibdBatchSize {
 		var hashesToRequest []*externalapi.DomainHash
 		if offset+ibdBatchSize < len(hashes) {
@@ -521,7 +547,7 @@ func (flow *handleRelayInvsFlow) syncMissingBlockBodies(highHash *externalapi.Do
 		}
 
 		for _, expectedHash := range hashesToRequest {
-			message, err := flow.dequeueIncomingMessageAndSkipInvs(common.DefaultTimeout)
+			message, err := flow.incomingRoute.DequeueWithTimeout(common.DefaultTimeout)
 			if err != nil {
 				return err
 			}
@@ -543,7 +569,7 @@ func (flow *handleRelayInvsFlow) syncMissingBlockBodies(highHash *externalapi.Do
 				return err
 			}
 
-			blockInsertionResult, err := flow.Domain().Consensus().ValidateAndInsertBlock(block)
+			virtualChangeSet, err := flow.Domain().Consensus().ValidateAndInsertBlock(block, false)
 			if err != nil {
 				if errors.Is(err, ruleerrors.ErrDuplicateBlock) {
 					log.Debugf("Skipping IBD Block %s as it has already been added to the DAG", blockHash)
@@ -551,27 +577,62 @@ func (flow *handleRelayInvsFlow) syncMissingBlockBodies(highHash *externalapi.Do
 				}
 				return protocolerrors.ConvertToBanningProtocolErrorIfRuleError(err, "invalid block %s", blockHash)
 			}
-			err = flow.OnNewBlock(block, blockInsertionResult)
+			err = flow.OnNewBlock(block, virtualChangeSet)
 			if err != nil {
 				return err
 			}
+
+			highestProcessedDAAScore = block.Header.DAAScore()
 		}
+
+		progressReporter.reportProgress(len(hashesToRequest), highestProcessedDAAScore)
+	}
+
+	return flow.resolveVirtual(highestProcessedDAAScore)
+}
+
+func (flow *handleIBDFlow) banIfBlockIsHeaderOnly(block *externalapi.DomainBlock) error {
+	if len(block.Transactions) == 0 {
+		return protocolerrors.Errorf(true, "sent header of %s block where expected block with body",
+			consensushashing.BlockHash(block))
 	}
 
 	return nil
 }
 
-// dequeueIncomingMessageAndSkipInvs is a convenience method to be used during
-// IBD. Inv messages are expected to arrive at any given moment, but should be
-// ignored while we're in IBD
-func (flow *handleRelayInvsFlow) dequeueIncomingMessageAndSkipInvs(timeout time.Duration) (appmessage.Message, error) {
-	for {
-		message, err := flow.incomingRoute.DequeueWithTimeout(timeout)
-		if err != nil {
-			return nil, err
+func (flow *handleIBDFlow) resolveVirtual(estimatedVirtualDAAScoreTarget uint64) error {
+	virtualDAAScoreStart, err := flow.Domain().Consensus().GetVirtualDAAScore()
+	if err != nil {
+		return err
+	}
+
+	for i := 0; ; i++ {
+		if i%10 == 0 {
+			virtualDAAScore, err := flow.Domain().Consensus().GetVirtualDAAScore()
+			if err != nil {
+				return err
+			}
+			var percents int
+			if estimatedVirtualDAAScoreTarget-virtualDAAScoreStart <= 0 {
+				percents = 100
+			} else {
+				percents = int(float64(virtualDAAScore-virtualDAAScoreStart) / float64(estimatedVirtualDAAScoreTarget-virtualDAAScoreStart) * 100)
+			}
+			log.Infof("Resolving virtual. Estimated progress: %d%%", percents)
 		}
-		if _, ok := message.(*appmessage.MsgInvRelayBlock); !ok {
-			return message, nil
+		virtualChangeSet, isCompletelyResolved, err := flow.Domain().Consensus().ResolveVirtual()
+		if err != nil {
+			return err
+		}
+
+		err = flow.OnVirtualChange(virtualChangeSet)
+		if err != nil {
+			return err
+		}
+
+		if isCompletelyResolved {
+			log.Infof("Resolved virtual")
+			return nil
 		}
 	}
 }

app/protocol/flows/v4/blockrelay/ibd_progress_reporter.go

@@ -0,0 +1,32 @@
+package blockrelay
+
+type ibdProgressReporter struct {
+	lowDAAScore                 uint64
+	highDAAScore                uint64
+	objectName                  string
+	totalDAAScoreDifference     uint64
+	lastReportedProgressPercent int
+	processed                   int
+}
+
+func newIBDProgressReporter(lowDAAScore uint64, highDAAScore uint64, objectName string) *ibdProgressReporter {
+	return &ibdProgressReporter{
+		lowDAAScore:                 lowDAAScore,
+		highDAAScore:                highDAAScore,
+		objectName:                  objectName,
+		totalDAAScoreDifference:     highDAAScore - lowDAAScore,
+		lastReportedProgressPercent: 0,
+		processed:                   0,
+	}
+}
+
+func (ipr *ibdProgressReporter) reportProgress(processedDelta int, highestProcessedDAAScore uint64) {
+	ipr.processed += processedDelta
+
+	relativeDAAScore := highestProcessedDAAScore - ipr.lowDAAScore
+	progressPercent := int((float64(relativeDAAScore) / float64(ipr.totalDAAScoreDifference)) * 100)
+	if progressPercent > ipr.lastReportedProgressPercent {
+		log.Infof("IBD: Processed %d %s (%d%%)", ipr.processed, ipr.objectName, progressPercent)
+		ipr.lastReportedProgressPercent = progressPercent
+	}
+}

app/protocol/flows/v4/blockrelay/ibd_with_headers_proof.go

@@ -0,0 +1,390 @@
+package blockrelay
+
+import (
+	"fmt"
+	"github.com/kaspanet/kaspad/app/appmessage"
+	"github.com/kaspanet/kaspad/app/protocol/common"
+	"github.com/kaspanet/kaspad/app/protocol/protocolerrors"
+	"github.com/kaspanet/kaspad/domain/consensus/model/externalapi"
+	"github.com/kaspanet/kaspad/domain/consensus/ruleerrors"
+	"github.com/kaspanet/kaspad/domain/consensus/utils/consensushashing"
+	"github.com/pkg/errors"
+	"time"
+)
+
+func (flow *handleIBDFlow) ibdWithHeadersProof(highHash *externalapi.DomainHash, highBlockDAAScore uint64) error {
+	err := flow.Domain().InitStagingConsensus()
+	if err != nil {
+		return err
+	}
+
+	err = flow.downloadHeadersAndPruningUTXOSet(highHash, highBlockDAAScore)
+	if err != nil {
+		if !flow.IsRecoverableError(err) {
+			return err
+		}
+
+		deleteStagingConsensusErr := flow.Domain().DeleteStagingConsensus()
+		if deleteStagingConsensusErr != nil {
+			return deleteStagingConsensusErr
+		}
+
+		return err
+	}
+
+	err = flow.Domain().CommitStagingConsensus()
+	if err != nil {
+		return err
+	}
+
+	err = flow.OnPruningPointUTXOSetOverride()
+	if err != nil {
+		return err
+	}
+
+	return nil
+}
+
+func (flow *handleIBDFlow) shouldSyncAndShouldDownloadHeadersProof(highBlock *externalapi.DomainBlock,
+	highestSharedBlockFound bool) (shouldDownload, shouldSync bool, err error) {
+
+	if !highestSharedBlockFound {
+		hasMoreBlueWorkThanSelectedTipAndPruningDepthMoreBlueScore, err := flow.checkIfHighHashHasMoreBlueWorkThanSelectedTipAndPruningDepthMoreBlueScore(highBlock)
+		if err != nil {
+			return false, false, err
+		}
+
+		if hasMoreBlueWorkThanSelectedTipAndPruningDepthMoreBlueScore {
+			return true, true, nil
+		}
+
+		return false, false, nil
+	}
+
+	return false, true, nil
+}
+
+func (flow *handleIBDFlow) checkIfHighHashHasMoreBlueWorkThanSelectedTipAndPruningDepthMoreBlueScore(highBlock *externalapi.DomainBlock) (bool, error) {
+	headersSelectedTip, err := flow.Domain().Consensus().GetHeadersSelectedTip()
+	if err != nil {
+		return false, err
+	}
+
+	headersSelectedTipInfo, err := flow.Domain().Consensus().GetBlockInfo(headersSelectedTip)
+	if err != nil {
+		return false, err
+	}
+
+	if highBlock.Header.BlueScore() < headersSelectedTipInfo.BlueScore+flow.Config().NetParams().PruningDepth() {
+		return false, nil
+	}
+
+	return highBlock.Header.BlueWork().Cmp(headersSelectedTipInfo.BlueWork) > 0, nil
+}
+
+func (flow *handleIBDFlow) syncAndValidatePruningPointProof() (*externalapi.DomainHash, error) {
+	log.Infof("Downloading the pruning point proof from %s", flow.peer)
+	err := flow.outgoingRoute.Enqueue(appmessage.NewMsgRequestPruningPointProof())
+	if err != nil {
+		return nil, err
+	}
+	message, err := flow.incomingRoute.DequeueWithTimeout(10 * time.Minute)
+	if err != nil {
+		return nil, err
+	}
+	pruningPointProofMessage, ok := message.(*appmessage.MsgPruningPointProof)
+	if !ok {
+		return nil, protocolerrors.Errorf(true, "received unexpected message type. "+
+			"expected: %s, got: %s", appmessage.CmdPruningPointProof, message.Command())
+	}
+	pruningPointProof := appmessage.MsgPruningPointProofToDomainPruningPointProof(pruningPointProofMessage)
+	err = flow.Domain().Consensus().ValidatePruningPointProof(pruningPointProof)
+	if err != nil {
+		if errors.As(err, &ruleerrors.RuleError{}) {
+			return nil, protocolerrors.Wrapf(true, err, "pruning point proof validation failed")
+		}
+		return nil, err
+	}
+
+	err = flow.Domain().StagingConsensus().ApplyPruningPointProof(pruningPointProof)
+	if err != nil {
+		return nil, err
+	}
+
+	return consensushashing.HeaderHash(pruningPointProof.Headers[0][len(pruningPointProof.Headers[0])-1]), nil
+}
+
+func (flow *handleIBDFlow) downloadHeadersAndPruningUTXOSet(highHash *externalapi.DomainHash, highBlockDAAScore uint64) error {
+	proofPruningPoint, err := flow.syncAndValidatePruningPointProof()
+	if err != nil {
+		return err
+	}
+
+	err = flow.syncPruningPointsAndPruningPointAnticone(proofPruningPoint)
+	if err != nil {
+		return err
+	}
+
+	// TODO: Remove this condition once there's more proper way to check finality violation
+	// in the headers proof.
+	if proofPruningPoint.Equal(flow.Config().NetParams().GenesisHash) {
+		return protocolerrors.Errorf(true, "the genesis pruning point violates finality")
+	}
+
+	err = flow.syncPruningPointFutureHeaders(flow.Domain().StagingConsensus(), proofPruningPoint, highHash, highBlockDAAScore)
+	if err != nil {
+		return err
+	}
+
+	log.Infof("Headers downloaded from peer %s", flow.peer)
+
+	highHashInfo, err := flow.Domain().StagingConsensus().GetBlockInfo(highHash)
+	if err != nil {
+		return err
+	}
+
+	if !highHashInfo.Exists {
+		return protocolerrors.Errorf(true, "the triggering IBD block was not sent")
+	}
+
+	err = flow.validatePruningPointFutureHeaderTimestamps()
+	if err != nil {
+		return err
+	}
+
+	log.Debugf("Syncing the current pruning point UTXO set")
+	syncedPruningPointUTXOSetSuccessfully, err := flow.syncPruningPointUTXOSet(flow.Domain().StagingConsensus(), proofPruningPoint)
+	if err != nil {
+		return err
+	}
+	if !syncedPruningPointUTXOSetSuccessfully {
+		log.Debugf("Aborting IBD because the pruning point UTXO set failed to sync")
+		return nil
+	}
+	log.Debugf("Finished syncing the current pruning point UTXO set")
+	return nil
+}
+
+func (flow *handleIBDFlow) syncPruningPointsAndPruningPointAnticone(proofPruningPoint *externalapi.DomainHash) error {
+	log.Infof("Downloading the past pruning points and the pruning point anticone from %s", flow.peer)
+	err := flow.outgoingRoute.Enqueue(appmessage.NewMsgRequestPruningPointAndItsAnticone())
+	if err != nil {
+		return err
+	}
+
+	err = flow.validateAndInsertPruningPoints(proofPruningPoint)
+	if err != nil {
+		return err
+	}
+
+	message, err := flow.incomingRoute.DequeueWithTimeout(common.DefaultTimeout)
+	if err != nil {
+		return err
+	}
+
+	msgTrustedData, ok := message.(*appmessage.MsgTrustedData)
+	if !ok {
+		return protocolerrors.Errorf(true, "received unexpected message type. "+
+			"expected: %s, got: %s", appmessage.CmdTrustedData, message.Command())
+	}
+
+	pruningPointWithMetaData, done, err := flow.receiveBlockWithTrustedData()
+	if err != nil {
+		return err
+	}
+
+	if done {
+		return protocolerrors.Errorf(true, "got `done` message before receiving the pruning point")
+	}
+
+	if !pruningPointWithMetaData.Block.Header.BlockHash().Equal(proofPruningPoint) {
+		return protocolerrors.Errorf(true, "first block with trusted data is not the pruning point")
+	}
+
+	err = flow.processBlockWithTrustedData(flow.Domain().StagingConsensus(), pruningPointWithMetaData, msgTrustedData)
+	if err != nil {
+		return err
+	}
+
+	for {
+		blockWithTrustedData, done, err := flow.receiveBlockWithTrustedData()
+		if err != nil {
+			return err
+		}
+
+		if done {
+			break
+		}
+
+		err = flow.processBlockWithTrustedData(flow.Domain().StagingConsensus(), blockWithTrustedData, msgTrustedData)
+		if err != nil {
+			return err
+		}
+	}
+
+	log.Infof("Finished downloading pruning point and its anticone from %s", flow.peer)
+	return nil
+}
+
+func (flow *handleIBDFlow) processBlockWithTrustedData(
+	consensus externalapi.Consensus, block *appmessage.MsgBlockWithTrustedDataV4, data *appmessage.MsgTrustedData) error {
+
+	blockWithTrustedData := &externalapi.BlockWithTrustedData{
+		Block:        appmessage.MsgBlockToDomainBlock(block.Block),
+		DAAWindow:    make([]*externalapi.TrustedDataDataDAAHeader, 0, len(block.DAAWindowIndices)),
+		GHOSTDAGData: make([]*externalapi.BlockGHOSTDAGDataHashPair, 0, len(block.GHOSTDAGDataIndices)),
+	}
+
+	for _, index := range block.DAAWindowIndices {
+		blockWithTrustedData.DAAWindow = append(blockWithTrustedData.DAAWindow, appmessage.TrustedDataDataDAABlockV4ToTrustedDataDataDAAHeader(data.DAAWindow[index]))
+	}
+
+	for _, index := range block.GHOSTDAGDataIndices {
+		blockWithTrustedData.GHOSTDAGData = append(blockWithTrustedData.GHOSTDAGData, appmessage.GHOSTDAGHashPairToDomainGHOSTDAGHashPair(data.GHOSTDAGData[index]))
+	}
+
+	_, err := consensus.ValidateAndInsertBlockWithTrustedData(blockWithTrustedData, false)
+	return err
+}
+
+func (flow *handleIBDFlow) receiveBlockWithTrustedData() (*appmessage.MsgBlockWithTrustedDataV4, bool, error) {
+	message, err := flow.incomingRoute.DequeueWithTimeout(common.DefaultTimeout)
+	if err != nil {
+		return nil, false, err
+	}
+
+	switch downCastedMessage := message.(type) {
+	case *appmessage.MsgBlockWithTrustedDataV4:
+		return downCastedMessage, false, nil
+	case *appmessage.MsgDoneBlocksWithTrustedData:
+		return nil, true, nil
+	default:
+		return nil, false,
+			protocolerrors.Errorf(true, "received unexpected message type. "+
+				"expected: %s or %s, got: %s",
+				(&appmessage.MsgBlockWithTrustedData{}).Command(),
+				(&appmessage.MsgDoneBlocksWithTrustedData{}).Command(),
+				downCastedMessage.Command())
+	}
+}
+
+func (flow *handleIBDFlow) receivePruningPoints() (*appmessage.MsgPruningPoints, error) {
+	message, err := flow.incomingRoute.DequeueWithTimeout(common.DefaultTimeout)
+	if err != nil {
+		return nil, err
+	}
+
+	msgPruningPoints, ok := message.(*appmessage.MsgPruningPoints)
+	if !ok {
+		return nil,
+			protocolerrors.Errorf(true, "received unexpected message type. "+
+				"expected: %s, got: %s", appmessage.CmdPruningPoints, message.Command())
+	}
+
+	return msgPruningPoints, nil
+}
+
+func (flow *handleIBDFlow) validateAndInsertPruningPoints(proofPruningPoint *externalapi.DomainHash) error {
+	currentPruningPoint, err := flow.Domain().Consensus().PruningPoint()
+	if err != nil {
+		return err
+	}
+
+	if currentPruningPoint.Equal(proofPruningPoint) {
+		return protocolerrors.Errorf(true, "the proposed pruning point is the same as the current pruning point")
+	}
+
+	pruningPoints, err := flow.receivePruningPoints()
+	if err != nil {
+		return err
+	}
+
+	headers := make([]externalapi.BlockHeader, len(pruningPoints.Headers))
+	for i, header := range pruningPoints.Headers {
+		headers[i] = appmessage.BlockHeaderToDomainBlockHeader(header)
+	}
+
+	arePruningPointsViolatingFinality, err := flow.Domain().Consensus().ArePruningPointsViolatingFinality(headers)
+	if err != nil {
+		return err
+	}
+
+	if arePruningPointsViolatingFinality {
+		// TODO: Find a better way to deal with finality conflicts.
+		return protocolerrors.Errorf(false, "pruning points are violating finality")
+	}
+
+	lastPruningPoint := consensushashing.HeaderHash(headers[len(headers)-1])
+	if !lastPruningPoint.Equal(proofPruningPoint) {
+		return protocolerrors.Errorf(true, "the proof pruning point is not equal to the last pruning "+
+			"point in the list")
+	}
+
+	err = flow.Domain().StagingConsensus().ImportPruningPoints(headers)
+	if err != nil {
+		return err
+	}
+
+	return nil
+}
+
+func (flow *handleIBDFlow) syncPruningPointUTXOSet(consensus externalapi.Consensus,
+	pruningPoint *externalapi.DomainHash) (bool, error) {
+
+	log.Infof("Checking if the suggested pruning point %s is compatible to the node DAG", pruningPoint)
+	isValid, err := flow.Domain().StagingConsensus().IsValidPruningPoint(pruningPoint)
+	if err != nil {
+		return false, err
+	}
+
+	if !isValid {
+		return false, protocolerrors.Errorf(true, "invalid pruning point %s", pruningPoint)
+	}
+
+	log.Info("Fetching the pruning point UTXO set")
+	isSuccessful, err := flow.fetchMissingUTXOSet(consensus, pruningPoint)
+	if err != nil {
+		return false, err
+	}
+
+	if !isSuccessful {
+		log.Infof("Couldn't successfully fetch the pruning point UTXO set. Stopping IBD.")
+		return false, nil
+	}
+
+	log.Info("Fetched the new pruning point UTXO set")
+	return true, nil
+}
+
+func (flow *handleIBDFlow) fetchMissingUTXOSet(consensus externalapi.Consensus, pruningPointHash *externalapi.DomainHash) (succeed bool, err error) {
+	defer func() {
+		err := flow.Domain().StagingConsensus().ClearImportedPruningPointData()
+		if err != nil {
+			panic(fmt.Sprintf("failed to clear imported pruning point data: %s", err))
+		}
+	}()
+
+	err = flow.outgoingRoute.Enqueue(appmessage.NewMsgRequestPruningPointUTXOSet(pruningPointHash))
+	if err != nil {
+		return false, err
+	}
+
+	receivedAll, err := flow.receiveAndInsertPruningPointUTXOSet(consensus, pruningPointHash)
+	if err != nil {
+		return false, err
+	}
+	if !receivedAll {
+		return false, nil
+	}
+
+	err = flow.Domain().StagingConsensus().ValidateAndInsertImportedPruningPoint(pruningPointHash)
+	if err != nil {
+		// TODO: Find a better way to deal with finality conflicts.
+		if errors.Is(err, ruleerrors.ErrSuggestedPruningViolatesFinality) {
+			return false, nil
+		}
+		return false, protocolerrors.ConvertToBanningProtocolErrorIfRuleError(err, "error with pruning point UTXO set")
+	}
+
+	return true, nil
+}

app/protocol/flows/v4/blockrelay/send_virtual_selected_parent_inv.go

@@ -4,12 +4,14 @@ import (
 	"github.com/kaspanet/kaspad/app/appmessage"
 	peerpkg "github.com/kaspanet/kaspad/app/protocol/peer"
 	"github.com/kaspanet/kaspad/domain"
+	"github.com/kaspanet/kaspad/infrastructure/config"
 	"github.com/kaspanet/kaspad/infrastructure/network/netadapter/router"
 )
 
 // SendVirtualSelectedParentInvContext is the interface for the context needed for the SendVirtualSelectedParentInv flow.
 type SendVirtualSelectedParentInvContext interface {
 	Domain() domain.Domain
+	Config() *config.Config
 }
 
 // SendVirtualSelectedParentInv sends a peer the selected parent hash of the virtual
@@ -21,6 +23,11 @@ func SendVirtualSelectedParentInv(context SendVirtualSelectedParentInvContext,
 		return err
 	}
 
+	if virtualSelectedParent.Equal(context.Config().NetParams().GenesisHash) {
+		log.Debugf("Skipping sending the virtual selected parent hash to peer %s because it's the genesis", peer)
+		return nil
+	}
+
 	log.Debugf("Sending virtual selected parent hash %s to peer %s", virtualSelectedParent, peer)
 
 	virtualSelectedParentInv := appmessage.NewMsgInvBlock(virtualSelectedParent)

app/protocol/flows/v4/register.go

@@ -0,0 +1,194 @@
+package v4
+
+import (
+	"github.com/kaspanet/kaspad/app/appmessage"
+	"github.com/kaspanet/kaspad/app/protocol/common"
+	"github.com/kaspanet/kaspad/app/protocol/flowcontext"
+	"github.com/kaspanet/kaspad/app/protocol/flows/v4/addressexchange"
+	"github.com/kaspanet/kaspad/app/protocol/flows/v4/blockrelay"
+	"github.com/kaspanet/kaspad/app/protocol/flows/v4/ping"
+	"github.com/kaspanet/kaspad/app/protocol/flows/v4/rejects"
+	"github.com/kaspanet/kaspad/app/protocol/flows/v4/transactionrelay"
+	peerpkg "github.com/kaspanet/kaspad/app/protocol/peer"
+	routerpkg "github.com/kaspanet/kaspad/infrastructure/network/netadapter/router"
+)
+
+type protocolManager interface {
+	RegisterFlow(name string, router *routerpkg.Router, messageTypes []appmessage.MessageCommand, isStopping *uint32,
+		errChan chan error, initializeFunc common.FlowInitializeFunc) *common.Flow
+	RegisterOneTimeFlow(name string, router *routerpkg.Router, messageTypes []appmessage.MessageCommand,
+		isStopping *uint32, stopChan chan error, initializeFunc common.FlowInitializeFunc) *common.Flow
+	RegisterFlowWithCapacity(name string, capacity int, router *routerpkg.Router,
+		messageTypes []appmessage.MessageCommand, isStopping *uint32,
+		errChan chan error, initializeFunc common.FlowInitializeFunc) *common.Flow
+	Context() *flowcontext.FlowContext
+}
+
+// Register is used in order to register all the protocol flows to the given router.
+func Register(m protocolManager, router *routerpkg.Router, errChan chan error, isStopping *uint32) (flows []*common.Flow) {
+	flows = registerAddressFlows(m, router, isStopping, errChan)
+	flows = append(flows, registerBlockRelayFlows(m, router, isStopping, errChan)...)
+	flows = append(flows, registerPingFlows(m, router, isStopping, errChan)...)
+	flows = append(flows, registerTransactionRelayFlow(m, router, isStopping, errChan)...)
+	flows = append(flows, registerRejectsFlow(m, router, isStopping, errChan)...)
+
+	return flows
+}
+
+func registerAddressFlows(m protocolManager, router *routerpkg.Router, isStopping *uint32, errChan chan error) []*common.Flow {
+	outgoingRoute := router.OutgoingRoute()
+
+	return []*common.Flow{
+		m.RegisterFlow("SendAddresses", router, []appmessage.MessageCommand{appmessage.CmdRequestAddresses}, isStopping, errChan,
+			func(incomingRoute *routerpkg.Route, peer *peerpkg.Peer) error {
+				return addressexchange.SendAddresses(m.Context(), incomingRoute, outgoingRoute)
+			},
+		),
+
+		m.RegisterOneTimeFlow("ReceiveAddresses", router, []appmessage.MessageCommand{appmessage.CmdAddresses}, isStopping, errChan,
+			func(incomingRoute *routerpkg.Route, peer *peerpkg.Peer) error {
+				return addressexchange.ReceiveAddresses(m.Context(), incomingRoute, outgoingRoute, peer)
+			},
+		),
+	}
+}
+
+func registerBlockRelayFlows(m protocolManager, router *routerpkg.Router, isStopping *uint32, errChan chan error) []*common.Flow {
+	outgoingRoute := router.OutgoingRoute()
+
+	return []*common.Flow{
+		m.RegisterOneTimeFlow("SendVirtualSelectedParentInv", router, []appmessage.MessageCommand{},
+			isStopping, errChan, func(route *routerpkg.Route, peer *peerpkg.Peer) error {
+				return blockrelay.SendVirtualSelectedParentInv(m.Context(), outgoingRoute, peer)
+			}),
+
+		m.RegisterFlow("HandleRelayInvs", router, []appmessage.MessageCommand{
+			appmessage.CmdInvRelayBlock, appmessage.CmdBlock, appmessage.CmdBlockLocator,
+		},
+			isStopping, errChan, func(incomingRoute *routerpkg.Route, peer *peerpkg.Peer) error {
+				return blockrelay.HandleRelayInvs(m.Context(), incomingRoute,
+					outgoingRoute, peer)
+			},
+		),
+
+		m.RegisterFlow("HandleIBD", router, []appmessage.MessageCommand{
+			appmessage.CmdDoneHeaders, appmessage.CmdUnexpectedPruningPoint, appmessage.CmdPruningPointUTXOSetChunk,
+			appmessage.CmdBlockHeaders, appmessage.CmdIBDBlockLocatorHighestHash, appmessage.CmdBlockWithTrustedDataV4,
+			appmessage.CmdDoneBlocksWithTrustedData, appmessage.CmdIBDBlockLocatorHighestHashNotFound,
+			appmessage.CmdDonePruningPointUTXOSetChunks, appmessage.CmdIBDBlock, appmessage.CmdPruningPoints,
+			appmessage.CmdPruningPointProof,
+			appmessage.CmdTrustedData,
+		},
+			isStopping, errChan, func(incomingRoute *routerpkg.Route, peer *peerpkg.Peer) error {
+				return blockrelay.HandleIBD(m.Context(), incomingRoute,
+					outgoingRoute, peer)
+			},
+		),
+
+		m.RegisterFlow("HandleRelayBlockRequests", router, []appmessage.MessageCommand{appmessage.CmdRequestRelayBlocks}, isStopping, errChan,
+			func(incomingRoute *routerpkg.Route, peer *peerpkg.Peer) error {
+				return blockrelay.HandleRelayBlockRequests(m.Context(), incomingRoute, outgoingRoute, peer)
+			},
+		),
+
+		m.RegisterFlow("HandleRequestBlockLocator", router,
+			[]appmessage.MessageCommand{appmessage.CmdRequestBlockLocator}, isStopping, errChan,
+			func(incomingRoute *routerpkg.Route, peer *peerpkg.Peer) error {
+				return blockrelay.HandleRequestBlockLocator(m.Context(), incomingRoute, outgoingRoute)
+			},
+		),
+
+		m.RegisterFlow("HandleRequestHeaders", router,
+			[]appmessage.MessageCommand{appmessage.CmdRequestHeaders, appmessage.CmdRequestNextHeaders}, isStopping, errChan,
+			func(incomingRoute *routerpkg.Route, peer *peerpkg.Peer) error {
+				return blockrelay.HandleRequestHeaders(m.Context(), incomingRoute, outgoingRoute, peer)
+			},
+		),
+
+		m.RegisterFlow("HandleIBDBlockRequests", router,
+			[]appmessage.MessageCommand{appmessage.CmdRequestIBDBlocks}, isStopping, errChan,
+			func(incomingRoute *routerpkg.Route, peer *peerpkg.Peer) error {
+				return blockrelay.HandleIBDBlockRequests(m.Context(), incomingRoute, outgoingRoute)
+			},
+		),
+
+		m.RegisterFlow("HandleRequestPruningPointUTXOSet", router,
+			[]appmessage.MessageCommand{appmessage.CmdRequestPruningPointUTXOSet,
+				appmessage.CmdRequestNextPruningPointUTXOSetChunk}, isStopping, errChan,
+			func(incomingRoute *routerpkg.Route, peer *peerpkg.Peer) error {
+				return blockrelay.HandleRequestPruningPointUTXOSet(m.Context(), incomingRoute, outgoingRoute)
+			},
+		),
+
+		m.RegisterFlow("HandlePruningPointAndItsAnticoneRequests", router,
+			[]appmessage.MessageCommand{appmessage.CmdRequestPruningPointAndItsAnticone}, isStopping, errChan,
+			func(incomingRoute *routerpkg.Route, peer *peerpkg.Peer) error {
+				return blockrelay.HandlePruningPointAndItsAnticoneRequests(m.Context(), incomingRoute, outgoingRoute, peer)
+			},
+		),
+
+		m.RegisterFlow("HandleIBDBlockLocator", router,
+			[]appmessage.MessageCommand{appmessage.CmdIBDBlockLocator}, isStopping, errChan,
+			func(incomingRoute *routerpkg.Route, peer *peerpkg.Peer) error {
+				return blockrelay.HandleIBDBlockLocator(m.Context(), incomingRoute, outgoingRoute, peer)
+			},
+		),
+
+		m.RegisterFlow("HandlePruningPointProofRequests", router,
+			[]appmessage.MessageCommand{appmessage.CmdRequestPruningPointProof}, isStopping, errChan,
+			func(incomingRoute *routerpkg.Route, peer *peerpkg.Peer) error {
+				return blockrelay.HandlePruningPointProofRequests(m.Context(), incomingRoute, outgoingRoute, peer)
+			},
+		),
+	}
+}
+
+func registerPingFlows(m protocolManager, router *routerpkg.Router, isStopping *uint32, errChan chan error) []*common.Flow {
+	outgoingRoute := router.OutgoingRoute()
+
+	return []*common.Flow{
+		m.RegisterFlow("ReceivePings", router, []appmessage.MessageCommand{appmessage.CmdPing}, isStopping, errChan,
+			func(incomingRoute *routerpkg.Route, peer *peerpkg.Peer) error {
+				return ping.ReceivePings(m.Context(), incomingRoute, outgoingRoute)
+			},
+		),
+
+		m.RegisterFlow("SendPings", router, []appmessage.MessageCommand{appmessage.CmdPong}, isStopping, errChan,
+			func(incomingRoute *routerpkg.Route, peer *peerpkg.Peer) error {
+				return ping.SendPings(m.Context(), incomingRoute, outgoingRoute, peer)
+			},
+		),
+	}
+}
+
+func registerTransactionRelayFlow(m protocolManager, router *routerpkg.Router, isStopping *uint32, errChan chan error) []*common.Flow {
+	outgoingRoute := router.OutgoingRoute()
+
+	return []*common.Flow{
+		m.RegisterFlowWithCapacity("HandleRelayedTransactions", 10_000, router,
+			[]appmessage.MessageCommand{appmessage.CmdInvTransaction, appmessage.CmdTx, appmessage.CmdTransactionNotFound}, isStopping, errChan,
+			func(incomingRoute *routerpkg.Route, peer *peerpkg.Peer) error {
+				return transactionrelay.HandleRelayedTransactions(m.Context(), incomingRoute, outgoingRoute)
+			},
+		),
+		m.RegisterFlow("HandleRequestTransactions", router,
+			[]appmessage.MessageCommand{appmessage.CmdRequestTransactions}, isStopping, errChan,
+			func(incomingRoute *routerpkg.Route, peer *peerpkg.Peer) error {
+				return transactionrelay.HandleRequestedTransactions(m.Context(), incomingRoute, outgoingRoute)
+			},
+		),
+	}
+}
+
+func registerRejectsFlow(m protocolManager, router *routerpkg.Router, isStopping *uint32, errChan chan error) []*common.Flow {
+	outgoingRoute := router.OutgoingRoute()
+
+	return []*common.Flow{
+		m.RegisterFlow("HandleRejects", router,
+			[]appmessage.MessageCommand{appmessage.CmdReject}, isStopping, errChan,
+			func(incomingRoute *routerpkg.Route, peer *peerpkg.Peer) error {
+				return rejects.HandleRejects(m.Context(), incomingRoute, outgoingRoute)
+			},
+		),
+	}
+}

app/protocol/flows/v4/rejects/handle_rejects.go

@@ -33,10 +33,5 @@ func (flow *handleRejectsFlow) start() error {
 	}
 	rejectMessage := message.(*appmessage.MsgReject)
 
-	const maxReasonLength = 255
-	if len(rejectMessage.Reason) > maxReasonLength {
-		return protocolerrors.Errorf(false, "got reject message longer than %d", maxReasonLength)
-	}
-
 	return protocolerrors.Errorf(false, "got reject message: `%s`", rejectMessage.Reason)
 }

app/protocol/flows/v4/testing/receiveaddresses_test.go

@@ -1,11 +1,11 @@
 package testing
 
 import (
+	"github.com/kaspanet/kaspad/app/protocol/flows/v4/addressexchange"
 	"testing"
 	"time"
 
 	"github.com/kaspanet/kaspad/app/appmessage"
-	"github.com/kaspanet/kaspad/app/protocol/flows/addressexchange"
 	peerpkg "github.com/kaspanet/kaspad/app/protocol/peer"
 	"github.com/kaspanet/kaspad/domain/consensus"
 	"github.com/kaspanet/kaspad/domain/consensus/utils/testutils"
@@ -21,8 +21,8 @@ func (f fakeReceiveAddressesContext) AddressManager() *addressmanager.AddressMan
 
 func TestReceiveAddressesErrors(t *testing.T) {
 	testutils.ForAllNets(t, true, func(t *testing.T, consensusConfig *consensus.Config) {
-		incomingRoute := router.NewRoute()
-		outgoingRoute := router.NewRoute()
+		incomingRoute := router.NewRoute("incoming")
+		outgoingRoute := router.NewRoute("outgoing")
 		peer := peerpkg.New(nil)
 		errChan := make(chan error)
 		go func() {

app/protocol/flows/v4/transactionrelay/handle_relayed_transactions.go

@@ -3,6 +3,7 @@ package transactionrelay
 import (
 	"github.com/kaspanet/kaspad/app/appmessage"
 	"github.com/kaspanet/kaspad/app/protocol/common"
+	"github.com/kaspanet/kaspad/app/protocol/flowcontext"
 	"github.com/kaspanet/kaspad/app/protocol/protocolerrors"
 	"github.com/kaspanet/kaspad/domain"
 	"github.com/kaspanet/kaspad/domain/consensus/model/externalapi"
@@ -18,9 +19,10 @@ import (
 type TransactionsRelayContext interface {
 	NetAdapter() *netadapter.NetAdapter
 	Domain() domain.Domain
-	SharedRequestedTransactions() *SharedRequestedTransactions
-	Broadcast(message appmessage.Message) error
+	SharedRequestedTransactions() *flowcontext.SharedRequestedTransactions
 	OnTransactionAddedToMempool()
+	EnqueueTransactionIDsForPropagation(transactionIDs []*externalapi.DomainTransactionID) error
+	IsIBDRunning() bool
 }
 
 type handleRelayedTransactionsFlow struct {
@@ -48,6 +50,10 @@ func (flow *handleRelayedTransactionsFlow) start() error {
 			return err
 		}
 
+		if flow.IsIBDRunning() {
+			continue
+		}
+
 		requestedIDs, err := flow.requestInvTransactions(inv)
 		if err != nil {
 			return err
@@ -68,7 +74,7 @@ func (flow *handleRelayedTransactionsFlow) requestInvTransactions(
 		if flow.isKnownTransaction(txID) {
 			continue
 		}
-		exists := flow.SharedRequestedTransactions().addIfNotExists(txID)
+		exists := flow.SharedRequestedTransactions().AddIfNotExists(txID)
 		if exists {
 			continue
 		}
@@ -82,7 +88,7 @@ func (flow *handleRelayedTransactionsFlow) requestInvTransactions(
 	msgGetTransactions := appmessage.NewMsgRequestTransactions(idsToRequest)
 	err = flow.outgoingRoute.Enqueue(msgGetTransactions)
 	if err != nil {
-		flow.SharedRequestedTransactions().removeMany(idsToRequest)
+		flow.SharedRequestedTransactions().RemoveMany(idsToRequest)
 		return nil, err
 	}
 	return idsToRequest, nil
@@ -119,8 +125,7 @@ func (flow *handleRelayedTransactionsFlow) readInv() (*appmessage.MsgInvTransact
 }
 
 func (flow *handleRelayedTransactionsFlow) broadcastAcceptedTransactions(acceptedTxIDs []*externalapi.DomainTransactionID) error {
-	inv := appmessage.NewMsgInvTransaction(acceptedTxIDs)
-	return flow.Broadcast(inv)
+	return flow.EnqueueTransactionIDsForPropagation(acceptedTxIDs)
 }
 
 // readMsgTxOrNotFound returns the next msgTx or msgTransactionNotFound in incomingRoute,
@@ -152,7 +157,7 @@ func (flow *handleRelayedTransactionsFlow) readMsgTxOrNotFound() (
 func (flow *handleRelayedTransactionsFlow) receiveTransactions(requestedTransactions []*externalapi.DomainTransactionID) error {
 	// In case the function returns earlier than expected, we want to make sure sharedRequestedTransactions is
 	// clean from any pending transactions.
-	defer flow.SharedRequestedTransactions().removeMany(requestedTransactions)
+	defer flow.SharedRequestedTransactions().RemoveMany(requestedTransactions)
 	for _, expectedID := range requestedTransactions {
 		msgTx, msgTxNotFound, err := flow.readMsgTxOrNotFound()
 		if err != nil {
@@ -173,17 +178,18 @@ func (flow *handleRelayedTransactionsFlow) receiveTransactions(requestedTransact
 				expectedID, txID)
 		}
 
-		err = flow.Domain().MiningManager().ValidateAndInsertTransaction(tx, true)
+		acceptedTransactions, err :=
+			flow.Domain().MiningManager().ValidateAndInsertTransaction(tx, false, true)
 		if err != nil {
 			ruleErr := &mempool.RuleError{}
 			if !errors.As(err, ruleErr) {
 				return errors.Wrapf(err, "failed to process transaction %s", txID)
 			}
 
-			shouldBan := true
+			shouldBan := false
 			if txRuleErr := (&mempool.TxRuleError{}); errors.As(ruleErr.Err, txRuleErr) {
-				if txRuleErr.RejectCode != mempool.RejectInvalid {
-					shouldBan = false
+				if txRuleErr.RejectCode == mempool.RejectInvalid {
+					shouldBan = true
 				}
 			}
 
@@ -193,7 +199,7 @@ func (flow *handleRelayedTransactionsFlow) receiveTransactions(requestedTransact
 
 			return protocolerrors.Errorf(true, "rejected transaction %s: %s", txID, ruleErr)
 		}
-		err = flow.broadcastAcceptedTransactions([]*externalapi.DomainTransactionID{txID})
+		err = flow.broadcastAcceptedTransactions(consensushashing.TransactionIDs(acceptedTransactions))
 		if err != nil {
 			return err
 		}

app/protocol/flows/v4/transactionrelay/handle_relayed_transactions_test.go

@@ -0,0 +1,196 @@
+package transactionrelay_test
+
+import (
+	"errors"
+	"github.com/kaspanet/kaspad/app/protocol/flowcontext"
+	"github.com/kaspanet/kaspad/app/protocol/flows/v4/transactionrelay"
+	"strings"
+	"testing"
+
+	"github.com/kaspanet/kaspad/app/protocol/protocolerrors"
+	"github.com/kaspanet/kaspad/domain"
+	"github.com/kaspanet/kaspad/domain/consensus"
+	"github.com/kaspanet/kaspad/domain/consensus/model/externalapi"
+	"github.com/kaspanet/kaspad/domain/consensus/utils/testutils"
+	"github.com/kaspanet/kaspad/domain/miningmanager/mempool"
+	"github.com/kaspanet/kaspad/infrastructure/logger"
+	"github.com/kaspanet/kaspad/util/panics"
+
+	"github.com/kaspanet/kaspad/app/appmessage"
+	"github.com/kaspanet/kaspad/infrastructure/config"
+	"github.com/kaspanet/kaspad/infrastructure/network/netadapter"
+	"github.com/kaspanet/kaspad/infrastructure/network/netadapter/router"
+)
+
+type mocTransactionsRelayContext struct {
+	netAdapter                  *netadapter.NetAdapter
+	domain                      domain.Domain
+	sharedRequestedTransactions *flowcontext.SharedRequestedTransactions
+}
+
+func (m *mocTransactionsRelayContext) NetAdapter() *netadapter.NetAdapter {
+	return m.netAdapter
+}
+
+func (m *mocTransactionsRelayContext) Domain() domain.Domain {
+	return m.domain
+}
+
+func (m *mocTransactionsRelayContext) SharedRequestedTransactions() *flowcontext.SharedRequestedTransactions {
+	return m.sharedRequestedTransactions
+}
+
+func (m *mocTransactionsRelayContext) EnqueueTransactionIDsForPropagation(transactionIDs []*externalapi.DomainTransactionID) error {
+	return nil
+}
+
+func (m *mocTransactionsRelayContext) OnTransactionAddedToMempool() {
+}
+
+func (m *mocTransactionsRelayContext) IsIBDRunning() bool {
+	return false
+}
+
+// TestHandleRelayedTransactionsNotFound tests the flow of  HandleRelayedTransactions when the peer doesn't
+// have the requested transactions in the mempool.
+func TestHandleRelayedTransactionsNotFound(t *testing.T) {
+	testutils.ForAllNets(t, true, func(t *testing.T, consensusConfig *consensus.Config) {
+
+		var log = logger.RegisterSubSystem("PROT")
+		var spawn = panics.GoroutineWrapperFunc(log)
+		factory := consensus.NewFactory()
+		tc, teardown, err := factory.NewTestConsensus(consensusConfig, "TestHandleRelayedTransactionsNotFound")
+		if err != nil {
+			t.Fatalf("Error setting up test consensus: %+v", err)
+		}
+		defer teardown(false)
+
+		sharedRequestedTransactions := flowcontext.NewSharedRequestedTransactions()
+		adapter, err := netadapter.NewNetAdapter(config.DefaultConfig())
+		if err != nil {
+			t.Fatalf("Failed to create a NetAdapter: %v", err)
+		}
+		domainInstance, err := domain.New(consensusConfig, mempool.DefaultConfig(&consensusConfig.Params), tc.Database())
+		if err != nil {
+			t.Fatalf("Failed to set up a domain instance: %v", err)
+		}
+		context := &mocTransactionsRelayContext{
+			netAdapter:                  adapter,
+			domain:                      domainInstance,
+			sharedRequestedTransactions: sharedRequestedTransactions,
+		}
+		incomingRoute := router.NewRoute("incoming")
+		defer incomingRoute.Close()
+		peerIncomingRoute := router.NewRoute("outgoing")
+		defer peerIncomingRoute.Close()
+
+		txID1 := externalapi.NewDomainTransactionIDFromByteArray(&[externalapi.DomainHashSize]byte{
+			0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+			0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+			0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+			0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01})
+		txID2 := externalapi.NewDomainTransactionIDFromByteArray(&[externalapi.DomainHashSize]byte{
+			0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+			0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+			0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+			0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02})
+		txIDs := []*externalapi.DomainTransactionID{txID1, txID2}
+		invMessage := appmessage.NewMsgInvTransaction(txIDs)
+		err = incomingRoute.Enqueue(invMessage)
+		if err != nil {
+			t.Fatalf("Unexpected error from incomingRoute.Enqueue: %v", err)
+		}
+		// The goroutine is representing the peer's actions.
+		spawn("peerResponseToTheTransactionsRequest", func() {
+			msg, err := peerIncomingRoute.Dequeue()
+			if err != nil {
+				t.Fatalf("Dequeue: %v", err)
+			}
+			inv := msg.(*appmessage.MsgRequestTransactions)
+
+			if len(txIDs) != len(inv.IDs) {
+				t.Fatalf("TestHandleRelayedTransactions: expected %d transactions ID, but got %d", len(txIDs), len(inv.IDs))
+			}
+
+			for i, id := range inv.IDs {
+				if txIDs[i].String() != id.String() {
+					t.Fatalf("TestHandleRelayedTransactions: expected equal txID: expected %s, but got %s", txIDs[i].String(), id.String())
+				}
+				err = incomingRoute.Enqueue(appmessage.NewMsgTransactionNotFound(txIDs[i]))
+				if err != nil {
+					t.Fatalf("Unexpected error from incomingRoute.Enqueue: %v", err)
+				}
+			}
+			// Insert an unexpected message type to stop the infinity loop.
+			err = incomingRoute.Enqueue(&appmessage.MsgAddresses{})
+			if err != nil {
+				t.Fatalf("Unexpected error from incomingRoute.Enqueue: %v", err)
+			}
+		})
+
+		err = transactionrelay.HandleRelayedTransactions(context, incomingRoute, peerIncomingRoute)
+		// Since we inserted an unexpected message type to stop the infinity loop,
+		// we expect the error will be infected from this specific message and also the
+		// error will count as a protocol message.
+		if protocolErr := (protocolerrors.ProtocolError{}); err == nil || !errors.As(err, &protocolErr) {
+			t.Fatalf("Expected to protocol error")
+		} else {
+			if !protocolErr.ShouldBan {
+				t.Fatalf("Exepcted shouldBan true, but got false.")
+			}
+			if !strings.Contains(err.Error(), "unexpected Addresses [code 3] message in the block relay flow while expecting an inv message") {
+				t.Fatalf("Unexpected error: expected: an error due to existence of an Addresses message "+
+					"in the block relay flow, but got: %v", protocolErr.Cause)
+			}
+		}
+	})
+}
+
+// TestOnClosedIncomingRoute verifies that an appropriate error message will be returned when
+// trying to dequeue a message from a closed route.
+func TestOnClosedIncomingRoute(t *testing.T) {
+	testutils.ForAllNets(t, true, func(t *testing.T, consensusConfig *consensus.Config) {
+
+		factory := consensus.NewFactory()
+		tc, teardown, err := factory.NewTestConsensus(consensusConfig, "TestOnClosedIncomingRoute")
+		if err != nil {
+			t.Fatalf("Error setting up test consensus: %+v", err)
+		}
+		defer teardown(false)
+
+		sharedRequestedTransactions := flowcontext.NewSharedRequestedTransactions()
+		adapter, err := netadapter.NewNetAdapter(config.DefaultConfig())
+		if err != nil {
+			t.Fatalf("Failed to creat a NetAdapter : %v", err)
+		}
+		domainInstance, err := domain.New(consensusConfig, mempool.DefaultConfig(&consensusConfig.Params), tc.Database())
+		if err != nil {
+			t.Fatalf("Failed to set up a domain instance: %v", err)
+		}
+		context := &mocTransactionsRelayContext{
+			netAdapter:                  adapter,
+			domain:                      domainInstance,
+			sharedRequestedTransactions: sharedRequestedTransactions,
+		}
+		incomingRoute := router.NewRoute("incoming")
+		outgoingRoute := router.NewRoute("outgoing")
+		defer outgoingRoute.Close()
+
+		txID := externalapi.NewDomainTransactionIDFromByteArray(&[externalapi.DomainHashSize]byte{
+			0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+			0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+			0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+			0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01})
+		txIDs := []*externalapi.DomainTransactionID{txID}
+
+		err = incomingRoute.Enqueue(&appmessage.MsgInvTransaction{TxIDs: txIDs})
+		if err != nil {
+			t.Fatalf("Unexpected error from incomingRoute.Enqueue: %v", err)
+		}
+		incomingRoute.Close()
+		err = transactionrelay.HandleRelayedTransactions(context, incomingRoute, outgoingRoute)
+		if err == nil || !errors.Is(err, router.ErrRouteClosed) {
+			t.Fatalf("Unexpected error: expected: %v, got : %v", router.ErrRouteClosed, err)
+		}
+	})
+}

app/protocol/flows/v4/transactionrelay/handle_requested_transactions_test.go

@@ -0,0 +1,91 @@
+package transactionrelay_test
+
+import (
+	"github.com/kaspanet/kaspad/app/protocol/flowcontext"
+	"github.com/kaspanet/kaspad/app/protocol/flows/v4/transactionrelay"
+	"testing"
+
+	"github.com/kaspanet/kaspad/app/appmessage"
+	"github.com/kaspanet/kaspad/domain"
+	"github.com/kaspanet/kaspad/domain/consensus"
+	"github.com/kaspanet/kaspad/domain/consensus/model/externalapi"
+	"github.com/kaspanet/kaspad/domain/consensus/utils/testutils"
+	"github.com/kaspanet/kaspad/domain/miningmanager/mempool"
+	"github.com/kaspanet/kaspad/infrastructure/config"
+	"github.com/kaspanet/kaspad/infrastructure/logger"
+	"github.com/kaspanet/kaspad/infrastructure/network/netadapter"
+	"github.com/kaspanet/kaspad/infrastructure/network/netadapter/router"
+	"github.com/kaspanet/kaspad/util/panics"
+	"github.com/pkg/errors"
+)
+
+// TestHandleRequestedTransactionsNotFound tests the flow of  HandleRequestedTransactions
+// when the requested transactions don't found in the mempool.
+func TestHandleRequestedTransactionsNotFound(t *testing.T) {
+	testutils.ForAllNets(t, true, func(t *testing.T, consensusConfig *consensus.Config) {
+		var log = logger.RegisterSubSystem("PROT")
+		var spawn = panics.GoroutineWrapperFunc(log)
+		factory := consensus.NewFactory()
+		tc, teardown, err := factory.NewTestConsensus(consensusConfig, "TestHandleRequestedTransactionsNotFound")
+		if err != nil {
+			t.Fatalf("Error setting up test Consensus: %+v", err)
+		}
+		defer teardown(false)
+
+		sharedRequestedTransactions := flowcontext.NewSharedRequestedTransactions()
+		adapter, err := netadapter.NewNetAdapter(config.DefaultConfig())
+		if err != nil {
+			t.Fatalf("Failed to create a NetAdapter: %v", err)
+		}
+		domainInstance, err := domain.New(consensusConfig, mempool.DefaultConfig(&consensusConfig.Params), tc.Database())
+		if err != nil {
+			t.Fatalf("Failed to set up a domain Instance: %v", err)
+		}
+		context := &mocTransactionsRelayContext{
+			netAdapter:                  adapter,
+			domain:                      domainInstance,
+			sharedRequestedTransactions: sharedRequestedTransactions,
+		}
+		incomingRoute := router.NewRoute("incoming")
+		outgoingRoute := router.NewRoute("outgoing")
+		defer outgoingRoute.Close()
+
+		txID1 := externalapi.NewDomainTransactionIDFromByteArray(&[externalapi.DomainHashSize]byte{
+			0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+			0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+			0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+			0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01})
+		txID2 := externalapi.NewDomainTransactionIDFromByteArray(&[externalapi.DomainHashSize]byte{
+			0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+			0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+			0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+			0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02})
+		txIDs := []*externalapi.DomainTransactionID{txID1, txID2}
+		msg := appmessage.NewMsgRequestTransactions(txIDs)
+		err = incomingRoute.Enqueue(msg)
+		if err != nil {
+			t.Fatalf("Unexpected error from incomingRoute.Enqueue: %v", err)
+		}
+		// The goroutine is representing the peer's actions.
+		spawn("peerResponseToTheTransactionsMessages", func() {
+			for i, id := range txIDs {
+				msg, err := outgoingRoute.Dequeue()
+				if err != nil {
+					t.Fatalf("Dequeue: %s", err)
+				}
+				outMsg := msg.(*appmessage.MsgTransactionNotFound)
+				if txIDs[i].String() != outMsg.ID.String() {
+					t.Fatalf("TestHandleRelayedTransactions: expected equal txID: expected %s, but got %s", txIDs[i].String(), id.String())
+				}
+			}
+			// Closed the incomingRoute for stop the infinity loop.
+			incomingRoute.Close()
+		})
+
+		err = transactionrelay.HandleRequestedTransactions(context, incomingRoute, outgoingRoute)
+		// Make sure the error is due to the closed route.
+		if err == nil || !errors.Is(err, router.ErrRouteClosed) {
+			t.Fatalf("Unexpected error: expected: %v, got : %v", router.ErrRouteClosed, err)
+		}
+	})
+}

app/protocol/manager.go

@@ -2,10 +2,12 @@ package protocol
 
 import (
 	"fmt"
-	"github.com/pkg/errors"
+	"github.com/kaspanet/kaspad/app/protocol/common"
 	"sync"
 	"sync/atomic"
 
+	"github.com/pkg/errors"
+
 	"github.com/kaspanet/kaspad/domain"
 
 	"github.com/kaspanet/kaspad/domain/consensus/model/externalapi"
@@ -61,8 +63,8 @@ func (m *Manager) IBDPeer() *peerpkg.Peer {
 }
 
 // AddTransaction adds transaction to the mempool and propagates it.
-func (m *Manager) AddTransaction(tx *externalapi.DomainTransaction) error {
-	return m.context.AddTransaction(tx)
+func (m *Manager) AddTransaction(tx *externalapi.DomainTransaction, allowOrphan bool) error {
+	return m.context.AddTransaction(tx, allowOrphan)
 }
 
 // AddBlock adds the given block to the DAG and propagates it.
@@ -70,11 +72,16 @@ func (m *Manager) AddBlock(block *externalapi.DomainBlock) error {
 	return m.context.AddBlock(block)
 }
 
-func (m *Manager) runFlows(flows []*flow, peer *peerpkg.Peer, errChan <-chan error, flowsWaitGroup *sync.WaitGroup) error {
+// Context returns the manager's flow context
+func (m *Manager) Context() *flowcontext.FlowContext {
+	return m.context
+}
+
+func (m *Manager) runFlows(flows []*common.Flow, peer *peerpkg.Peer, errChan <-chan error, flowsWaitGroup *sync.WaitGroup) error {
 	flowsWaitGroup.Add(len(flows))
 	for _, flow := range flows {
-		executeFunc := flow.executeFunc // extract to new variable so that it's not overwritten
-		spawn(fmt.Sprintf("flow-%s", flow.name), func() {
+		executeFunc := flow.ExecuteFunc // extract to new variable so that it's not overwritten
+		spawn(fmt.Sprintf("flow-%s", flow.Name), func() {
 			executeFunc(peer)
 			flowsWaitGroup.Done()
 		})
@@ -83,6 +90,11 @@ func (m *Manager) runFlows(flows []*flow, peer *peerpkg.Peer, errChan <-chan err
 	return <-errChan
 }
 
+// SetOnVirtualChange sets the onVirtualChangeHandler handler
+func (m *Manager) SetOnVirtualChange(onVirtualChangeHandler flowcontext.OnVirtualChangeHandler) {
+	m.context.SetOnVirtualChangeHandler(onVirtualChangeHandler)
+}
+
 // SetOnBlockAddedToDAGHandler sets the onBlockAddedToDAG handler
 func (m *Manager) SetOnBlockAddedToDAGHandler(onBlockAddedToDAGHandler flowcontext.OnBlockAddedToDAGHandler) {
 	m.context.SetOnBlockAddedToDAGHandler(onBlockAddedToDAGHandler)

app/protocol/peer/peer.go

@@ -13,10 +13,6 @@ import (
 	"github.com/kaspanet/kaspad/util/mstime"
 )
 
-// maxProtocolVersion version is the maximum supported protocol
-// version this kaspad node supports
-const maxProtocolVersion = 1
-
 // Peer holds data about a peer.
 type Peer struct {
 	connection *netadapter.NetConnection
@@ -35,6 +31,8 @@ type Peer struct {
 	lastPingNonce    uint64        // The nonce of the last ping we sent
 	lastPingTime     time.Time     // Time we sent last ping
 	lastPingDuration time.Duration // Time for last ping to return
+
+	ibdRequestChannel chan *externalapi.DomainBlock // A channel used to communicate IBD requests between flows
 }
 
 // New returns a new Peer
@@ -42,6 +40,7 @@ func New(connection *netadapter.NetConnection) *Peer {
 	return &Peer{
 		connection:        connection,
 		connectionStarted: time.Now(),
+		ibdRequestChannel: make(chan *externalapi.DomainBlock),
 	}
 }
 
@@ -76,6 +75,11 @@ func (p *Peer) AdvertisedProtocolVersion() uint32 {
 	return p.advertisedProtocolVerion
 }
 
+// ProtocolVersion returns the protocol version which is used when communicating with the peer.
+func (p *Peer) ProtocolVersion() uint32 {
+	return p.protocolVersion
+}
+
 // TimeConnected returns the time since the connection to this been has been started.
 func (p *Peer) TimeConnected() time.Duration {
 	return time.Since(p.connectionStarted)
@@ -87,7 +91,7 @@ func (p *Peer) IsOutbound() bool {
 }
 
 // UpdateFieldsFromMsgVersion updates the peer with the data from the version message.
-func (p *Peer) UpdateFieldsFromMsgVersion(msg *appmessage.MsgVersion) {
+func (p *Peer) UpdateFieldsFromMsgVersion(msg *appmessage.MsgVersion, maxProtocolVersion uint32) {
 	// Negotiate the protocol version.
 	p.advertisedProtocolVerion = msg.ProtocolVersion
 	p.protocolVersion = mathUtil.MinUint32(maxProtocolVersion, p.advertisedProtocolVerion)
@@ -142,3 +146,8 @@ func (p *Peer) LastPingDuration() time.Duration {
 
 	return p.lastPingDuration
 }
+
+// IBDRequestChannel returns the channel used in order to communicate an IBD request between peer flows
+func (p *Peer) IBDRequestChannel() chan *externalapi.DomainBlock {
+	return p.ibdRequestChannel
+}

app/protocol/protocol.go

@@ -1,33 +1,23 @@
 package protocol
 
 import (
-	"github.com/kaspanet/kaspad/app/protocol/flows/rejects"
-	"github.com/kaspanet/kaspad/infrastructure/network/connmanager"
+	"github.com/kaspanet/kaspad/app/protocol/common"
+	"github.com/kaspanet/kaspad/app/protocol/flows/ready"
+	v4 "github.com/kaspanet/kaspad/app/protocol/flows/v4"
 	"sync"
 	"sync/atomic"
 
 	"github.com/kaspanet/kaspad/app/appmessage"
-	"github.com/kaspanet/kaspad/app/protocol/flows/addressexchange"
-	"github.com/kaspanet/kaspad/app/protocol/flows/blockrelay"
 	"github.com/kaspanet/kaspad/app/protocol/flows/handshake"
-	"github.com/kaspanet/kaspad/app/protocol/flows/ping"
-	"github.com/kaspanet/kaspad/app/protocol/flows/transactionrelay"
 	peerpkg "github.com/kaspanet/kaspad/app/protocol/peer"
 	"github.com/kaspanet/kaspad/app/protocol/protocolerrors"
 	"github.com/kaspanet/kaspad/infrastructure/network/addressmanager"
+	"github.com/kaspanet/kaspad/infrastructure/network/connmanager"
 	"github.com/kaspanet/kaspad/infrastructure/network/netadapter"
 	routerpkg "github.com/kaspanet/kaspad/infrastructure/network/netadapter/router"
 	"github.com/pkg/errors"
 )
 
-type flowInitializeFunc func(route *routerpkg.Route, peer *peerpkg.Peer) error
-type flowExecuteFunc func(peer *peerpkg.Peer)
-
-type flow struct {
-	name        string
-	executeFunc flowExecuteFunc
-}
-
 func (m *Manager) routerInitializer(router *routerpkg.Router, netConnection *netadapter.NetConnection) {
 	// isStopping flag is raised the moment that the connection associated with this router is disconnected
 	// errChan is used by the flow goroutines to return to runFlows when an error occurs.
@@ -35,8 +25,7 @@ func (m *Manager) routerInitializer(router *routerpkg.Router, netConnection *net
 	isStopping := uint32(0)
 	errChan := make(chan error)
 
-	flows := m.registerFlows(router, errChan, &isStopping)
-	receiveVersionRoute, sendVersionRoute := registerHandshakeRoutes(router)
+	receiveVersionRoute, sendVersionRoute, receiveReadyRoute := registerHandshakeRoutes(router)
 
 	// After flows were registered - spawn a new thread that will wait for connection to finish initializing
 	// and start receiving messages
@@ -84,6 +73,21 @@ func (m *Manager) routerInitializer(router *routerpkg.Router, netConnection *net
 		}
 		defer m.context.RemoveFromPeers(peer)
 
+		var flows []*common.Flow
+		log.Infof("Registering p2p flows for peer %s for protocol version %d", peer, peer.ProtocolVersion())
+		switch peer.ProtocolVersion() {
+		case 4:
+			flows = v4.Register(m, router, errChan, &isStopping)
+		default:
+			panic(errors.Errorf("no way to handle protocol version %d", peer.ProtocolVersion()))
+		}
+
+		err = ready.HandleReady(receiveReadyRoute, router.OutgoingRoute(), peer)
+		if err != nil {
+			m.handleError(err, netConnection, router.OutgoingRoute())
+			return
+		}
+
 		removeHandshakeRoutes(router)
 
 		flowsWaitGroup := &sync.WaitGroup{}
@@ -102,11 +106,11 @@ func (m *Manager) routerInitializer(router *routerpkg.Router, netConnection *net
 
 func (m *Manager) handleError(err error, netConnection *netadapter.NetConnection, outgoingRoute *routerpkg.Route) {
 	if protocolErr := (protocolerrors.ProtocolError{}); errors.As(err, &protocolErr) {
-		if !m.context.Config().DisableBanning && protocolErr.ShouldBan {
+		if m.context.Config().EnableBanning && protocolErr.ShouldBan {
 			log.Warnf("Banning %s (reason: %s)", netConnection, protocolErr.Cause)
 
 			err := m.context.ConnectionManager().Ban(netConnection)
-			if !errors.Is(err, connmanager.ErrCannotBanPermanent) {
+			if err != nil && !errors.Is(err, connmanager.ErrCannotBanPermanent) {
 				panic(err)
 			}
 
@@ -130,159 +134,11 @@ func (m *Manager) handleError(err error, netConnection *netadapter.NetConnection
 	panic(err)
 }
 
-func (m *Manager) registerFlows(router *routerpkg.Router, errChan chan error, isStopping *uint32) (flows []*flow) {
-	flows = m.registerAddressFlows(router, isStopping, errChan)
-	flows = append(flows, m.registerBlockRelayFlows(router, isStopping, errChan)...)
-	flows = append(flows, m.registerPingFlows(router, isStopping, errChan)...)
-	flows = append(flows, m.registerTransactionRelayFlow(router, isStopping, errChan)...)
-	flows = append(flows, m.registerRejectsFlow(router, isStopping, errChan)...)
+// RegisterFlow registers a flow to the given router.
+func (m *Manager) RegisterFlow(name string, router *routerpkg.Router, messageTypes []appmessage.MessageCommand, isStopping *uint32,
+	errChan chan error, initializeFunc common.FlowInitializeFunc) *common.Flow {
 
-	return flows
-}
-
-func (m *Manager) registerAddressFlows(router *routerpkg.Router, isStopping *uint32, errChan chan error) []*flow {
-	outgoingRoute := router.OutgoingRoute()
-
-	return []*flow{
-		m.registerFlow("SendAddresses", router, []appmessage.MessageCommand{appmessage.CmdRequestAddresses}, isStopping, errChan,
-			func(incomingRoute *routerpkg.Route, peer *peerpkg.Peer) error {
-				return addressexchange.SendAddresses(m.context, incomingRoute, outgoingRoute)
-			},
-		),
-
-		m.registerOneTimeFlow("ReceiveAddresses", router, []appmessage.MessageCommand{appmessage.CmdAddresses}, isStopping, errChan,
-			func(incomingRoute *routerpkg.Route, peer *peerpkg.Peer) error {
-				return addressexchange.ReceiveAddresses(m.context, incomingRoute, outgoingRoute, peer)
-			},
-		),
-	}
-}
-
-func (m *Manager) registerBlockRelayFlows(router *routerpkg.Router, isStopping *uint32, errChan chan error) []*flow {
-	outgoingRoute := router.OutgoingRoute()
-
-	return []*flow{
-		m.registerOneTimeFlow("SendVirtualSelectedParentInv", router, []appmessage.MessageCommand{},
-			isStopping, errChan, func(route *routerpkg.Route, peer *peerpkg.Peer) error {
-				return blockrelay.SendVirtualSelectedParentInv(m.context, outgoingRoute, peer)
-			}),
-
-		m.registerFlow("HandleRelayInvs", router, []appmessage.MessageCommand{
-			appmessage.CmdInvRelayBlock, appmessage.CmdBlock, appmessage.CmdBlockLocator, appmessage.CmdIBDBlock,
-			appmessage.CmdDoneHeaders, appmessage.CmdUnexpectedPruningPoint, appmessage.CmdPruningPointUTXOSetChunk,
-			appmessage.CmdBlockHeaders, appmessage.CmdPruningPointHash, appmessage.CmdIBDBlockLocatorHighestHash,
-			appmessage.CmdIBDBlockLocatorHighestHashNotFound, appmessage.CmdDonePruningPointUTXOSetChunks},
-			isStopping, errChan, func(incomingRoute *routerpkg.Route, peer *peerpkg.Peer) error {
-				return blockrelay.HandleRelayInvs(m.context, incomingRoute,
-					outgoingRoute, peer)
-			},
-		),
-
-		m.registerFlow("HandleRelayBlockRequests", router, []appmessage.MessageCommand{appmessage.CmdRequestRelayBlocks}, isStopping, errChan,
-			func(incomingRoute *routerpkg.Route, peer *peerpkg.Peer) error {
-				return blockrelay.HandleRelayBlockRequests(m.context, incomingRoute, outgoingRoute, peer)
-			},
-		),
-
-		m.registerFlow("HandleRequestBlockLocator", router,
-			[]appmessage.MessageCommand{appmessage.CmdRequestBlockLocator}, isStopping, errChan,
-			func(incomingRoute *routerpkg.Route, peer *peerpkg.Peer) error {
-				return blockrelay.HandleRequestBlockLocator(m.context, incomingRoute, outgoingRoute)
-			},
-		),
-
-		m.registerFlow("HandleRequestHeaders", router,
-			[]appmessage.MessageCommand{appmessage.CmdRequestHeaders, appmessage.CmdRequestNextHeaders}, isStopping, errChan,
-			func(incomingRoute *routerpkg.Route, peer *peerpkg.Peer) error {
-				return blockrelay.HandleRequestHeaders(m.context, incomingRoute, outgoingRoute, peer)
-			},
-		),
-
-		m.registerFlow("HandleRequestPruningPointUTXOSetAndBlock", router,
-			[]appmessage.MessageCommand{appmessage.CmdRequestPruningPointUTXOSetAndBlock,
-				appmessage.CmdRequestNextPruningPointUTXOSetChunk}, isStopping, errChan,
-			func(incomingRoute *routerpkg.Route, peer *peerpkg.Peer) error {
-				return blockrelay.HandleRequestPruningPointUTXOSetAndBlock(m.context, incomingRoute, outgoingRoute)
-			},
-		),
-
-		m.registerFlow("HandleIBDBlockRequests", router,
-			[]appmessage.MessageCommand{appmessage.CmdRequestIBDBlocks}, isStopping, errChan,
-			func(incomingRoute *routerpkg.Route, peer *peerpkg.Peer) error {
-				return blockrelay.HandleIBDBlockRequests(m.context, incomingRoute, outgoingRoute)
-			},
-		),
-
-		m.registerFlow("HandlePruningPointHashRequests", router,
-			[]appmessage.MessageCommand{appmessage.CmdRequestPruningPointHash}, isStopping, errChan,
-			func(incomingRoute *routerpkg.Route, peer *peerpkg.Peer) error {
-				return blockrelay.HandlePruningPointHashRequests(m.context, incomingRoute, outgoingRoute)
-			},
-		),
-
-		m.registerFlow("HandleIBDBlockLocator", router,
-			[]appmessage.MessageCommand{appmessage.CmdIBDBlockLocator}, isStopping, errChan,
-			func(incomingRoute *routerpkg.Route, peer *peerpkg.Peer) error {
-				return blockrelay.HandleIBDBlockLocator(m.context, incomingRoute, outgoingRoute, peer)
-			},
-		),
-	}
-}
-
-func (m *Manager) registerPingFlows(router *routerpkg.Router, isStopping *uint32, errChan chan error) []*flow {
-	outgoingRoute := router.OutgoingRoute()
-
-	return []*flow{
-		m.registerFlow("ReceivePings", router, []appmessage.MessageCommand{appmessage.CmdPing}, isStopping, errChan,
-			func(incomingRoute *routerpkg.Route, peer *peerpkg.Peer) error {
-				return ping.ReceivePings(m.context, incomingRoute, outgoingRoute)
-			},
-		),
-
-		m.registerFlow("SendPings", router, []appmessage.MessageCommand{appmessage.CmdPong}, isStopping, errChan,
-			func(incomingRoute *routerpkg.Route, peer *peerpkg.Peer) error {
-				return ping.SendPings(m.context, incomingRoute, outgoingRoute, peer)
-			},
-		),
-	}
-}
-
-func (m *Manager) registerTransactionRelayFlow(router *routerpkg.Router, isStopping *uint32, errChan chan error) []*flow {
-	outgoingRoute := router.OutgoingRoute()
-
-	return []*flow{
-		m.registerFlowWithCapacity("HandleRelayedTransactions", 10_000, router,
-			[]appmessage.MessageCommand{appmessage.CmdInvTransaction, appmessage.CmdTx, appmessage.CmdTransactionNotFound}, isStopping, errChan,
-			func(incomingRoute *routerpkg.Route, peer *peerpkg.Peer) error {
-				return transactionrelay.HandleRelayedTransactions(m.context, incomingRoute, outgoingRoute)
-			},
-		),
-		m.registerFlow("HandleRequestTransactions", router,
-			[]appmessage.MessageCommand{appmessage.CmdRequestTransactions}, isStopping, errChan,
-			func(incomingRoute *routerpkg.Route, peer *peerpkg.Peer) error {
-				return transactionrelay.HandleRequestedTransactions(m.context, incomingRoute, outgoingRoute)
-			},
-		),
-	}
-}
-
-func (m *Manager) registerRejectsFlow(router *routerpkg.Router, isStopping *uint32, errChan chan error) []*flow {
-	outgoingRoute := router.OutgoingRoute()
-
-	return []*flow{
-		m.registerFlow("HandleRejects", router,
-			[]appmessage.MessageCommand{appmessage.CmdReject}, isStopping, errChan,
-			func(incomingRoute *routerpkg.Route, peer *peerpkg.Peer) error {
-				return rejects.HandleRejects(m.context, incomingRoute, outgoingRoute)
-			},
-		),
-	}
-}
-
-func (m *Manager) registerFlow(name string, router *routerpkg.Router, messageTypes []appmessage.MessageCommand, isStopping *uint32,
-	errChan chan error, initializeFunc flowInitializeFunc) *flow {
-
-	route, err := router.AddIncomingRoute(messageTypes)
+	route, err := router.AddIncomingRoute(name, messageTypes)
 	if err != nil {
 		panic(err)
 	}
@@ -290,11 +146,12 @@ func (m *Manager) registerFlow(name string, router *routerpkg.Router, messageTyp
 	return m.registerFlowForRoute(route, name, isStopping, errChan, initializeFunc)
 }
 
-func (m *Manager) registerFlowWithCapacity(name string, capacity int, router *routerpkg.Router,
+// RegisterFlowWithCapacity registers a flow to the given router with a custom capacity.
+func (m *Manager) RegisterFlowWithCapacity(name string, capacity int, router *routerpkg.Router,
 	messageTypes []appmessage.MessageCommand, isStopping *uint32,
-	errChan chan error, initializeFunc flowInitializeFunc) *flow {
+	errChan chan error, initializeFunc common.FlowInitializeFunc) *common.Flow {
 
-	route, err := router.AddIncomingRouteWithCapacity(capacity, messageTypes)
+	route, err := router.AddIncomingRouteWithCapacity(name, capacity, messageTypes)
 	if err != nil {
 		panic(err)
 	}
@@ -303,11 +160,11 @@ func (m *Manager) registerFlowWithCapacity(name string, capacity int, router *ro
 }
 
 func (m *Manager) registerFlowForRoute(route *routerpkg.Route, name string, isStopping *uint32,
-	errChan chan error, initializeFunc flowInitializeFunc) *flow {
+	errChan chan error, initializeFunc common.FlowInitializeFunc) *common.Flow {
 
-	return &flow{
-		name: name,
-		executeFunc: func(peer *peerpkg.Peer) {
+	return &common.Flow{
+		Name: name,
+		ExecuteFunc: func(peer *peerpkg.Peer) {
 			err := initializeFunc(route, peer)
 			if err != nil {
 				m.context.HandleError(err, name, isStopping, errChan)
@@ -317,17 +174,18 @@ func (m *Manager) registerFlowForRoute(route *routerpkg.Route, name string, isSt
 	}
 }
 
-func (m *Manager) registerOneTimeFlow(name string, router *routerpkg.Router, messageTypes []appmessage.MessageCommand,
-	isStopping *uint32, stopChan chan error, initializeFunc flowInitializeFunc) *flow {
+// RegisterOneTimeFlow registers a one-time flow (that exits once some operations are done) to the given router.
+func (m *Manager) RegisterOneTimeFlow(name string, router *routerpkg.Router, messageTypes []appmessage.MessageCommand,
+	isStopping *uint32, stopChan chan error, initializeFunc common.FlowInitializeFunc) *common.Flow {
 
-	route, err := router.AddIncomingRoute(messageTypes)
+	route, err := router.AddIncomingRoute(name, messageTypes)
 	if err != nil {
 		panic(err)
 	}
 
-	return &flow{
-		name: name,
-		executeFunc: func(peer *peerpkg.Peer) {
+	return &common.Flow{
+		Name: name,
+		ExecuteFunc: func(peer *peerpkg.Peer) {
 			defer func() {
 				err := router.RemoveRoute(messageTypes)
 				if err != nil {
@@ -345,22 +203,27 @@ func (m *Manager) registerOneTimeFlow(name string, router *routerpkg.Router, mes
 }
 
 func registerHandshakeRoutes(router *routerpkg.Router) (
-	receiveVersionRoute *routerpkg.Route, sendVersionRoute *routerpkg.Route) {
-	receiveVersionRoute, err := router.AddIncomingRoute([]appmessage.MessageCommand{appmessage.CmdVersion})
+	receiveVersionRoute, sendVersionRoute, receiveReadyRoute *routerpkg.Route) {
+	receiveVersionRoute, err := router.AddIncomingRoute("recieveVersion - incoming", []appmessage.MessageCommand{appmessage.CmdVersion})
 	if err != nil {
 		panic(err)
 	}
 
-	sendVersionRoute, err = router.AddIncomingRoute([]appmessage.MessageCommand{appmessage.CmdVerAck})
+	sendVersionRoute, err = router.AddIncomingRoute("sendVersion - incoming", []appmessage.MessageCommand{appmessage.CmdVerAck})
 	if err != nil {
 		panic(err)
 	}
 
-	return receiveVersionRoute, sendVersionRoute
+	receiveReadyRoute, err = router.AddIncomingRoute("recieveReady - incoming", []appmessage.MessageCommand{appmessage.CmdReady})
+	if err != nil {
+		panic(err)
+	}
+
+	return receiveVersionRoute, sendVersionRoute, receiveReadyRoute
 }
 
 func removeHandshakeRoutes(router *routerpkg.Router) {
-	err := router.RemoveRoute([]appmessage.MessageCommand{appmessage.CmdVersion, appmessage.CmdVerAck})
+	err := router.RemoveRoute([]appmessage.MessageCommand{appmessage.CmdVersion, appmessage.CmdVerAck, appmessage.CmdReady})
 	if err != nil {
 		panic(err)
 	}

app/rpc/manager.go

@@ -48,23 +48,11 @@ func NewManager(
 }
 
 // NotifyBlockAddedToDAG notifies the manager that a block has been added to the DAG
-func (m *Manager) NotifyBlockAddedToDAG(block *externalapi.DomainBlock, blockInsertionResult *externalapi.BlockInsertionResult) error {
+func (m *Manager) NotifyBlockAddedToDAG(block *externalapi.DomainBlock, virtualChangeSet *externalapi.VirtualChangeSet) error {
 	onEnd := logger.LogAndMeasureExecutionTime(log, "RPCManager.NotifyBlockAddedToDAG")
 	defer onEnd()
 
-	if m.context.Config.UTXOIndex {
-		err := m.notifyUTXOsChanged(blockInsertionResult)
-		if err != nil {
-			return err
-		}
-	}
-
-	err := m.notifyVirtualSelectedParentBlueScoreChanged()
-	if err != nil {
-		return err
-	}
-
-	err = m.notifyVirtualSelectedParentChainChanged(blockInsertionResult)
+	err := m.NotifyVirtualChange(virtualChangeSet)
 	if err != nil {
 		return err
 	}
@@ -78,6 +66,36 @@ func (m *Manager) NotifyBlockAddedToDAG(block *externalapi.DomainBlock, blockIns
 	return m.context.NotificationManager.NotifyBlockAdded(blockAddedNotification)
 }
 
+// NotifyVirtualChange notifies the manager that the virtual block has been changed.
+func (m *Manager) NotifyVirtualChange(virtualChangeSet *externalapi.VirtualChangeSet) error {
+	onEnd := logger.LogAndMeasureExecutionTime(log, "RPCManager.NotifyBlockAddedToDAG")
+	defer onEnd()
+
+	if m.context.Config.UTXOIndex {
+		err := m.notifyUTXOsChanged(virtualChangeSet)
+		if err != nil {
+			return err
+		}
+	}
+
+	err := m.notifyVirtualSelectedParentBlueScoreChanged()
+	if err != nil {
+		return err
+	}
+
+	err = m.notifyVirtualDaaScoreChanged()
+	if err != nil {
+		return err
+	}
+
+	err = m.notifyVirtualSelectedParentChainChanged(virtualChangeSet)
+	if err != nil {
+		return err
+	}
+
+	return nil
+}
+
 // NotifyPruningPointUTXOSetOverride notifies the manager whenever the UTXO index
 // resets due to pruning point change via IBD.
 func (m *Manager) NotifyPruningPointUTXOSetOverride() error {
@@ -112,11 +130,11 @@ func (m *Manager) NotifyFinalityConflictResolved(finalityBlockHash string) error
 	return m.context.NotificationManager.NotifyFinalityConflictResolved(notification)
 }
 
-func (m *Manager) notifyUTXOsChanged(blockInsertionResult *externalapi.BlockInsertionResult) error {
+func (m *Manager) notifyUTXOsChanged(virtualChangeSet *externalapi.VirtualChangeSet) error {
 	onEnd := logger.LogAndMeasureExecutionTime(log, "RPCManager.NotifyUTXOsChanged")
 	defer onEnd()
 
-	utxoIndexChanges, err := m.context.UTXOIndex.Update(blockInsertionResult)
+	utxoIndexChanges, err := m.context.UTXOIndex.Update(virtualChangeSet)
 	if err != nil {
 		return err
 	}
@@ -153,12 +171,25 @@ func (m *Manager) notifyVirtualSelectedParentBlueScoreChanged() error {
 	return m.context.NotificationManager.NotifyVirtualSelectedParentBlueScoreChanged(notification)
 }
 
-func (m *Manager) notifyVirtualSelectedParentChainChanged(blockInsertionResult *externalapi.BlockInsertionResult) error {
+func (m *Manager) notifyVirtualDaaScoreChanged() error {
+	onEnd := logger.LogAndMeasureExecutionTime(log, "RPCManager.NotifyVirtualDaaScoreChanged")
+	defer onEnd()
+
+	virtualDAAScore, err := m.context.Domain.Consensus().GetVirtualDAAScore()
+	if err != nil {
+		return err
+	}
+
+	notification := appmessage.NewVirtualDaaScoreChangedNotificationMessage(virtualDAAScore)
+	return m.context.NotificationManager.NotifyVirtualDaaScoreChanged(notification)
+}
+
+func (m *Manager) notifyVirtualSelectedParentChainChanged(virtualChangeSet *externalapi.VirtualChangeSet) error {
 	onEnd := logger.LogAndMeasureExecutionTime(log, "RPCManager.NotifyVirtualSelectedParentChainChanged")
 	defer onEnd()
 
 	notification, err := m.context.ConvertVirtualSelectedParentChainChangesToChainChangedNotificationMessage(
-		blockInsertionResult.VirtualSelectedParentChainChanges)
+		virtualChangeSet.VirtualSelectedParentChainChanges)
 	if err != nil {
 		return err
 	}

app/rpc/rpc.go

@@ -28,6 +28,7 @@ var handlers = map[appmessage.MessageCommand]handler{
 	appmessage.CmdGetVirtualSelectedParentChainFromBlockRequestMessage:      rpchandlers.HandleGetVirtualSelectedParentChainFromBlock,
 	appmessage.CmdGetBlocksRequestMessage:                                   rpchandlers.HandleGetBlocks,
 	appmessage.CmdGetBlockCountRequestMessage:                               rpchandlers.HandleGetBlockCount,
+	appmessage.CmdGetBalanceByAddressRequestMessage:                         rpchandlers.HandleGetBalanceByAddress,
 	appmessage.CmdGetBlockDAGInfoRequestMessage:                             rpchandlers.HandleGetBlockDAGInfo,
 	appmessage.CmdResolveFinalityConflictRequestMessage:                     rpchandlers.HandleResolveFinalityConflict,
 	appmessage.CmdNotifyFinalityConflictsRequestMessage:                     rpchandlers.HandleNotifyFinalityConflicts,
@@ -37,6 +38,7 @@ var handlers = map[appmessage.MessageCommand]handler{
 	appmessage.CmdNotifyUTXOsChangedRequestMessage:                          rpchandlers.HandleNotifyUTXOsChanged,
 	appmessage.CmdStopNotifyingUTXOsChangedRequestMessage:                   rpchandlers.HandleStopNotifyingUTXOsChanged,
 	appmessage.CmdGetUTXOsByAddressesRequestMessage:                         rpchandlers.HandleGetUTXOsByAddresses,
+	appmessage.CmdGetBalancesByAddressesRequestMessage:                      rpchandlers.HandleGetBalancesByAddresses,
 	appmessage.CmdGetVirtualSelectedParentBlueScoreRequestMessage:           rpchandlers.HandleGetVirtualSelectedParentBlueScore,
 	appmessage.CmdNotifyVirtualSelectedParentBlueScoreChangedRequestMessage: rpchandlers.HandleNotifyVirtualSelectedParentBlueScoreChanged,
 	appmessage.CmdBanRequestMessage:                                         rpchandlers.HandleBan,
@@ -44,6 +46,8 @@ var handlers = map[appmessage.MessageCommand]handler{
 	appmessage.CmdGetInfoRequestMessage:                                     rpchandlers.HandleGetInfo,
 	appmessage.CmdNotifyPruningPointUTXOSetOverrideRequestMessage:           rpchandlers.HandleNotifyPruningPointUTXOSetOverrideRequest,
 	appmessage.CmdStopNotifyingPruningPointUTXOSetOverrideRequestMessage:    rpchandlers.HandleStopNotifyingPruningPointUTXOSetOverrideRequest,
+	appmessage.CmdEstimateNetworkHashesPerSecondRequestMessage:              rpchandlers.HandleEstimateNetworkHashesPerSecond,
+	appmessage.CmdNotifyVirtualDaaScoreChangedRequestMessage:                rpchandlers.HandleNotifyVirtualDaaScoreChanged,
 }
 
 func (m *Manager) routerInitializer(router *router.Router, netConnection *netadapter.NetConnection) {
@@ -51,7 +55,7 @@ func (m *Manager) routerInitializer(router *router.Router, netConnection *netada
 	for messageType := range handlers {
 		messageTypes = append(messageTypes, messageType)
 	}
-	incomingRoute, err := router.AddIncomingRoute(messageTypes)
+	incomingRoute, err := router.AddIncomingRoute("rpc router", messageTypes)
 	if err != nil {
 		panic(err)
 	}

app/rpc/rpccontext/chain_changed.go

@@ -3,7 +3,6 @@ package rpccontext
 import (
 	"github.com/kaspanet/kaspad/app/appmessage"
 	"github.com/kaspanet/kaspad/domain/consensus/model/externalapi"
-	"github.com/kaspanet/kaspad/domain/consensus/utils/consensushashing"
 )
 
 // ConvertVirtualSelectedParentChainChangesToChainChangedNotificationMessage converts
@@ -16,29 +15,9 @@ func (ctx *Context) ConvertVirtualSelectedParentChainChangesToChainChangedNotifi
 		removedChainBlockHashes[i] = removed.String()
 	}
 
-	addedChainBlocks := make([]*appmessage.ChainBlock, len(selectedParentChainChanges.Added))
+	addedChainBlocks := make([]string, len(selectedParentChainChanges.Added))
 	for i, added := range selectedParentChainChanges.Added {
-		acceptanceData, err := ctx.Domain.Consensus().GetBlockAcceptanceData(added)
-		if err != nil {
-			return nil, err
-		}
-		acceptedBlocks := make([]*appmessage.AcceptedBlock, len(acceptanceData))
-		for j, acceptedBlock := range acceptanceData {
-			acceptedTransactionIDs := make([]string, len(acceptedBlock.TransactionAcceptanceData))
-			for k, transaction := range acceptedBlock.TransactionAcceptanceData {
-				transactionID := consensushashing.TransactionID(transaction.Transaction)
-				acceptedTransactionIDs[k] = transactionID.String()
-			}
-			acceptedBlocks[j] = &appmessage.AcceptedBlock{
-				Hash:                   acceptedBlock.BlockHash.String(),
-				AcceptedTransactionIDs: acceptedTransactionIDs,
-			}
-		}
-
-		addedChainBlocks[i] = &appmessage.ChainBlock{
-			Hash:           added.String(),
-			AcceptedBlocks: acceptedBlocks,
-		}
+		addedChainBlocks[i] = added.String()
 	}
 
 	return appmessage.NewVirtualSelectedParentChainChangedNotificationMessage(removedChainBlockHashes, addedChainBlocks), nil