From db2aa88c32d4e373b4cb7cfefbaf175d3884efe8 Mon Sep 17 00:00:00 2001 From: Mark Nadal Date: Mon, 29 May 2017 00:06:53 -0700 Subject: [PATCH] comment SEA --- sea.js | 360 +++++++++++++++++++++++++++++++++------------------------ 1 file changed, 209 insertions(+), 151 deletions(-) diff --git a/sea.js b/sea.js index d09a69fe..7809288f 100644 --- a/sea.js +++ b/sea.js @@ -3,190 +3,123 @@ Security, Encryption, and Authorization: SEA.js */ + // NECESSARY PRE-REQUISITE: http://gun.js.org/explainers/data/security.html + /* THIS IS AN EARLY ALPHA!!! */ if(typeof require !== "undefined"){ var Gun = require('./gun') } if(typeof window !== "undefined"){ var Gun = window.Gun } - Gun.on('opt', function(at){ - if(!at.sea){ - at.sea = {own: {}}; - at.gun.on('in', security, at); - at.gun.on('out', signature, at); - } - this.to.next(at); - }); - - Gun.on('node', function(at){ // TODO: Warning: Needs to be converted to `gun.on('node')`! - var own = (at.gun.back(-1)._).sea.own, soul = at.get, pub = own[soul] || soul.slice(4), vertex = (at.gun._).put; - Gun.node.is(at.put, function(val, key, node){ - vertex[key] = node[key] = val = SEA.read(val, pub); - if(val && val['#'] && (key = Gun.val.rel.is(val))){ - if('alias/' === soul.slice(0,6)){ return } - own[key] = pub; - } - }); - }) - - function signature(at){ - at.user = at.gun.back(-1)._.user; - security.call(this, at); - } - - function security(at){ - var cat = this.as, sea = cat.sea, to = this.to; - if(at.get){ - var soul = at.get['#']; - //console.log("SEA get", soul); - if(soul){ - if('alias' === soul){ - return to.next(at); - } else - if('alias/' === soul.slice(0,6)){ - return to.next(at); - } else { - return to.next(at); // TODO: allow all reads? - } - } - } - if(at.put){ - var no, tmp, u; - Gun.obj.map(at.put, function(node, soul){ - if(no){ return no = true } - if(Gun.obj.empty(node, '_')){ return } - if('alias' === soul){ - Gun.obj.map(node, function(val, key){ - if('_' === key){ return } - if(!val){ return no = true } - if('alias/'+key !== Gun.val.rel.is(val)){ - return no = true; - } - }); - } else - if('alias/' === soul.slice(0,6)){ - Gun.obj.map(node, function(val, key){ - if('_' === key){ return } - if(!val){ return no = true } - if(key === Gun.val.rel.is(val)){ return } - return no = true; - }); - } else - if('pub/' === soul.slice(0,4)){ - tmp = soul.slice(4); - Gun.obj.map(node, function(val, key){ - if('_' === key){ return } - if('pub' === key){ - if(val === tmp){ return } - return no = true; - } - if(at.user){ - if(tmp === at.user._.pub){ - val = node[key] = SEA.write(val, at.user._.sea); - } - } - if(u === (val = SEA.read(val, tmp))){ - return no = true; - } - }); - } else - if(at.user && (tmp = at.user._.sea)){ - Gun.obj.map(node, function(val, key){ - if('_' === key){ return } - node[key] = SEA.write(val, tmp); - }); - } else - if(tmp = sea.own[soul]){ - Gun.obj.map(node, function(val, key){ - if('_' === key){ return } - if(u === (val = SEA.read(val, tmp))){ - return no = true; - } - }); - } else { - return no = true; - } - }); - if(no){ - if(!at || !Gun.tag.secure){ return } - Gun.on('secure', function(at){ - this.off(); - if(!at){ return } - to.next(at); - }); - Gun.on('secure', at); - return; - } - //console.log("SEA put", at.put); - return to.next(at); - } - to.next(at); - } - + // let's extend the gun chain with a `user` function. + // only one user can be logged in at a time, per gun instance. Gun.chain.user = function(){ - var root = this.back(-1); - var user = root._.user || (root._.user = root.chain()); - user.create = User.create; - user.auth = User.auth; - return user; + var root = this.back(-1); // always reference the root gun instance. + var user = root._.user || (root._.user = root.chain()); // create a user context. + user.create = User.create; // attach a factory method to it. + user.auth = User.auth; // and a login method. + return user; // return the user! } + + // EXAMPLE! Use it this way: + ;(function(){return; + localStorage.clear(); + + var gun = Gun(); + var user = gun.user(); + + Gun.on('auth', function(at){ + // do something once logged in. + }); + Gun.on('secure', function(at){ + // enforce some rules about shared app level data + var no; + if(no){ return } + this.to.next(at); + }); + + user.create("test", "password"); // create a user from a username alias and a password phrase. + user.auth("test", "password"); // authenticate and log in the user! + + }()); + + // How does it work? function User(){}; + // Well first we have to actually create a user. That is what this function does. User.create = function(alias, pass, cb){ var root = this.back(-1); cb = cb || function(){}; + // Because more than 1 user might have the same username, we treat the alias as a list of those users. root.get('alias/'+alias).get(function(at, ev){ ev.off(); if(at.put){ + // If we can enforce that a user name is already taken, it might be nice to try, but this is not guaranteed. return cb({err: Gun.log("User already created!")}); } var user = {alias: alias, salt: Gun.text.random(64)}; + // pseudo-randomly create a salt, then use CryptoJS's PBKDF2 function to extend the password with it. SEA.proof(pass, user.salt, function(proof){ + // this will take some short amount of time to produce a proof, which slows brute force attacks. var pair = SEA.pair(); + // now we have generated a brand new ECDSA key pair for the user account. user.pub = pair.pub; + // the user's public key doesn't need to be signed. But everything else needs to be signed with it! user.alias = SEA.write(alias, pair.priv); user.salt = SEA.write(user.salt, pair.priv); + // to keep the private key safe, we AES encrypt it with the proof of work! user.auth = SEA.write(SEA.en(pair.priv, proof), pair.priv); var tmp = 'pub/'+pair.pub; //console.log("create", user, pair.pub); + // awesome, now we can actually save the user with their public key as their ID. root.get(tmp).put(user); + // next up, we want to associate the alias with the public key. So we add it to the alias list. var ref = root.get('alias/'+alias).put(Gun.obj.put({}, tmp, Gun.val.rel.ify(tmp))); + // callback that the user has been created. (Note: ok = 0 because we didn't wait for disk to ack) cb({ok: 0, pub: pair.pub}); }); }); } + // now that we have created a user, we want to authenticate them! User.auth = function(alias, pass, cb){ var root = this.back(-1); cb = cb || function(){}; + // load all public keys associated with the username alias we want to log in with. root.get('alias/'+alias).get(function(at, ev){ ev.off(); if(!at.put){ + // if no user, don't do anything. return cb({err: Gun.log("No user!")}); } + // then attempt to log into each one until we find ours! + // (if two users have the same username AND the same password... that would be bad) Gun.obj.map(at.put, function(val, key){ + // grab the account associated with this public key. root.get(key).get(function(at, ev){ key = key.slice(4); ev.off(); if(!at.put){ return cb({err: "Public key does not exist!"}) } + // attempt to PBKDF2 extend the password with the salt. (Verifying the signature gives us the plain text salt.) SEA.proof(pass, SEA.read(at.put.salt, key), function(proof){ + // the proof of work is evidence that we've spent some time/effort trying to log in, this slows brute force. var priv = SEA.de(SEA.read(at.put.auth, key), proof); - if(priv){ - //console.log("Signed in!", at.put); - /*if(window.sessionStorage){ - sessionStorage.tmp = data.pass; - sessionStorage.alias = data.alias; - } - c.me = Gun.obj.copy(alias); - return route('people'); - */ + // now we have AES decrypted the private key, from when we encrypted it with the proof at registration. + if(priv){ // if we were successful, then that means... + // we're logged in! var user = root._.user; + // add our credentials in-memory only to our root gun instance user._ = at.gun._; + // so that way we can use the credentials to encrypt/decrypt data user._.is = user.is = {}; + // that is input/output through gun (see below) user._.sea = priv; user._.pub = key; //console.log("authorized", user._); + // callbacks success with the user data credentials. cb(user._); + // emit an auth event, useful for page redirects and stuff. Gun.on('auth', user._); return; } + // Or else we failed to log in... console.log("Failed to sign in!"); cb({err: "Attempt failed"}); }); @@ -194,9 +127,148 @@ }); }); } + // After we have a GUN extension to make user registration/login easy, we then need to handle everything else. + + // We do this with a GUN adapter, we first listen to when a gun instance is created (and when its options change) + Gun.on('opt', function(at){ + if(!at.sea){ // only add SEA once per instance, on the "at" context. + at.sea = {own: {}}; + at.gun.on('in', security, at); // now listen to all input data, acting as a firewall. + at.gun.on('out', signature, at); // and output listeners, to encrypt outgoing data. + } + this.to.next(at); // make sure to call the "next" middleware adapter. + }); + + // Alright, this next adapter gets run at the per node level in the graph database. + // This will let us verify that every property on a node has a value signed by a public key we trust. + // If the signature does not match, the data is just `undefined` so it doesn't get passed on. + // If it does match, then we transform the in-memory "view" of the data into its plain value (without the signature). + // Now NOTE! Some data is "system" data, not user data. Example: List of public keys, aliases, etc. + // This data is self-enforced (the value can only match its ID), but that is handled in the `security` function. + // From the self-enforced data, we can see all the edges in the graph that belong to a public key. + // Example: pub/ASDF is the ID of a node with ASDF as its public key, signed alias and salt, and + // its encrypted private key, but it might also have other signed values on it like `profile = ` edge. + // Using that directed edge's ID, we can then track (in memory) which IDs belong to which keys. + // Here is a problem: Multiple public keys can "claim" any node's ID, so this is dangerous! + // This means we should ONLY trust our "friends" (our key ring) public keys, not any ones. + // I have not yet added that to SEA yet in this alpha release. That is coming soon, but beware in the meanwhile! + Gun.on('node', function(at){ // TODO: Warning: Need to switch to `gun.on('node')`! Do not use `Gun.on('node'` in your apps! + var own = (at.gun.back(-1)._).sea.own, soul = at.get, pub = own[soul] || soul.slice(4), vertex = (at.gun._).put; + Gun.node.is(at.put, function(val, key, node){ // for each property on the node. + vertex[key] = node[key] = val = SEA.read(val, pub); // verify signature and get plain value. + if(val && val['#'] && (key = Gun.val.rel.is(val))){ // if it is a relation / edge + if('alias/' === soul.slice(0,6)){ return } // if it is itself + own[key] = pub; // associate the public key with a node + } + }); + }) + + // signature handles data output, it is a proxy to the security function. + function signature(at){ + at.user = at.gun.back(-1)._.user; + security.call(this, at); + } + + // okay! The security function handles all the heavy lifting. + // It needs to deal read and write of input and output of system data, account/public key data, and regular data. + // This is broken down into some pretty clear edge cases, let's go over them: + function security(at){ + var cat = this.as, sea = cat.sea, to = this.to; + if(at.get){ + // if there is a request to read data from us, then... + var soul = at.get['#']; + if(soul){ // for now, only allow direct IDs to be read. + if('alias' === soul){ // Allow reading the list of usernames/aliases in the system? + return to.next(at); // yes. + } else + if('alias/' === soul.slice(0,6)){ // Allow reading the list of public keys associated with an alias? + return to.next(at); // yes. + } else { // Allow reading everything? + return to.next(at); // yes // TODO: No! Make this a callback/event that people can filter on. + } + } + } + if(at.put){ + // if there is a request to write data to us, then... + var no, tmp, u; + Gun.obj.map(at.put, function(node, soul){ // for each over every node in the graph + if(no){ return no = true } + if(Gun.obj.empty(node, '_')){ return } // ignore empty updates, don't reject them. + if('alias' === soul){ // special case for shared system data, the list of aliases. + Gun.obj.map(node, function(val, key){ // for each over the node to look at each property/value. + if('_' === key){ return } // ignore meta data + if(!val){ return no = true } // data MUST exist + if('alias/'+key !== Gun.val.rel.is(val)){ // in fact, it must be EXACTLY equal to itself + return no = true; // if it isn't, reject. + } + }); + } else + if('alias/' === soul.slice(0,6)){ // special case for shared system data, the list of public keys for an alias. + Gun.obj.map(node, function(val, key){ // for each over the node to look at each property/value. + if('_' === key){ return } // ignore meta data + if(!val){ return no = true } // data MUST exist + if(key === Gun.val.rel.is(val)){ return } // and the ID must be EXACTLY equal to its property + return no = true; // that way nobody can tamper with the list of public keys. + }); + } else + if('pub/' === soul.slice(0,4)){ // special case, account data for a public key. + tmp = soul.slice(4); // ignore the 'pub/' prefix on the public key. + Gun.obj.map(node, function(val, key){ // for each over the account data, looking at each property/value. + if('_' === key){ return } // ignore meta data. + if('pub' === key){ + if(val === tmp){ return } // the account MUST have a `pub` property that equals the ID of the public key. + return no = true; // if not, reject the update. + } + if(at.user){ // if we are logged in + if(tmp === at.user._.pub){ // as this user + val = node[key] = SEA.write(val, at.user._.sea); // then sign our updates as we output them. + } // (if we are lying about our signature, other peer's will reject our update) + } + if(u === (val = SEA.read(val, tmp))){ // make sure the signature matches the account it claims to be on. + return no = true; // reject any updates that are signed with a mismatched account. + } + }); + } else + if(at.user && (tmp = at.user._.sea)){ // not special case, if we are logged in, then + Gun.obj.map(node, function(val, key){ // any data we output needs to + if('_' === key){ return } + node[key] = SEA.write(val, tmp); // be signed by our logged in account. + }); + } else // TODO: BUG! These two if-statements are not exclusive to each other!!! + if(tmp = sea.own[soul]){ // not special case, if we receive an update on an ID associated with a public key, then + Gun.obj.map(node, function(val, key){ // for each over the property/values + if('_' === key){ return } + if(u === (val = SEA.read(val, tmp))){ // and verify they were signed by the associated public key! + return no = true; // reject the update if it fails to match. + } + }); + } else { // reject any/all other updates by default. + return no = true; + } + }); + if(no){ // if we got a rejection then... + if(!at || !Gun.tag.secure){ return } + Gun.on('secure', function(at){ // (below) emit a special event for the developer to handle security. + this.off(); + if(!at){ return } + to.next(at); // and if they went ahead and explicitly called "next" (to us) with data, then approve. + }); + Gun.on('secure', at); + return; // else wise, reject. + } + //console.log("SEA put", at.put); + // if we did not get a rejection, then pass forward to the "next" adapter middleware. + return to.next(at); + } + to.next(at); // pass forward any data we do not know how to handle or process (this allows custom security protocols). + } + function SEA(){}; + // create a wrapper library around CryptoJS and JSRSAsign. + // of course, these libraries are required. A bundle is included in lib/cryptography.js if(typeof CryptoJS === "undefined"){ console.log("Error: CryptoJS required!") } if(typeof KJUR === "undefined"){ console.log("Error: JSRSAsign required!") } + // now wrap the various AES, ECDSA, PBKDF2 functions we called above. SEA.proof = function(pass,salt,cb){ cb(CryptoJS.PBKDF2(pass, salt, {keySize: 512/32, iterations: 100}).toString(CryptoJS.enc.Base64)); }; @@ -247,29 +319,15 @@ }; SEA.froto = {stringify:function(a){var b={ct:a.ciphertext.toString(CryptoJS.enc.Base64)};a.iv&&(b.iv=a.iv.toString());a.salt&&(b.s=a.salt.toString());return JSON.stringify(b)},parse:function(a){a=JSON.parse(a);var b=CryptoJS.lib.CipherParams.create({ciphertext:CryptoJS.enc.Base64.parse(a.ct)});a.iv&&(b.iv=CryptoJS.enc.Hex.parse(a.iv));a.s&&(b.salt=CryptoJS.enc.Hex.parse(a.s));return b}}; Gun.SEA = SEA; - -}()); -;(function(){return; - localStorage.clear(); - - var gun = window.gun = Gun(); - - var user = gun.user(); - - Gun.on('auth', function(at){ - // do something once logged in. - }); - - Gun.on('secure', function(at){ - // enforce some rules about shared app level data - var no; - if(no){ return } - this.to.next(at); - }); - - user.create("test", "password"); - - user.auth("test", "password"); + // all done! + // Obviously it is missing MANY necessary features. This is only an alpha release. + // Please experiment with it, audit what I've done so far, and complain about what needs to be added. + // SEA should be a full suite that is easy and seamless to use. + // Again, scroll naer the top, where I provide an EXAMPLE of how to create a user and sign in. + // Once logged in, the rest of the code you just read handled automatically signing/validating data. + // But all other behavior needs to be equally easy, like opinionated ways of + // Adding friends (trusted public keys), sending private messages, etc. + // Cheers! Tell me what you think. }()); \ No newline at end of file