gun/sea/index.js
2018-06-26 13:06:29 -07:00

228 lines
11 KiB
JavaScript

const SEA = require('./sea')
const Gun = SEA.Gun;
// 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.on('in', security, at); // now listen to all input data, acting as a firewall.
at.on('out', signature, at); // and output listeners, to encrypt outgoing data.
at.on('node', each, at);
}
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: ~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 = <ID>` 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!
function each(msg){ // TODO: Warning: Need to switch to `gun.on('node')`! Do not use `Gun.on('node'` in your apps!
// NOTE: THE SECURITY FUNCTION HAS ALREADY VERIFIED THE DATA!!!
// WE DO NOT NEED TO RE-VERIFY AGAIN, JUST TRANSFORM IT TO PLAINTEXT.
var to = this.to, vertex = (msg.$._).put, c = 0, d;
Gun.node.is(msg.put, function(val, key, node){ c++; // for each property on the node
// TODO: consider async/await use here...
SEA.verify(val, false, function(data){ c--; // false just extracts the plain data.
node[key] = val = data; // transform to plain value.
if(d && !c && (c = -1)){ to.next(msg) }
});
});
d = true;
if(d && !c){ to.next(msg) }
return;
}
// signature handles data output, it is a proxy to the security function.
function signature(msg){
if(msg.user){
return this.to.next(msg);
}
var ctx = this.as;
msg.user = ctx.user;
security.call(this, msg);
}
// 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(msg){
var at = this.as, sea = at.sea, to = this.to;
if(msg.get){
// if there is a request to read data from us, then...
var soul = msg.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(msg); // yes.
} else
if('~@' === soul.slice(0,2)){ // Allow reading the list of public keys associated with an alias?
return to.next(msg); // yes.
} else { // Allow reading everything?
return to.next(msg); // yes // TODO: No! Make this a callback/event that people can filter on.
}
}
}
if(msg.put){
// potentially parallel async operations!!!
var check = {}, each = {}, u;
each.node = function(node, soul){
if(Gun.obj.empty(node, '_')){ return check['node'+soul] = 0 } // ignore empty updates, don't reject them.
Gun.obj.map(node, each.way, {soul: soul, node: node});
};
each.way = function(val, key){
var soul = this.soul, node = this.node, tmp;
if('_' === key){ return } // ignore meta data
if('~@' === soul){ // special case for shared system data, the list of aliases.
each.alias(val, key, node, soul); return;
}
if('~@' === soul.slice(0,2)){ // special case for shared system data, the list of public keys for an alias.
each.pubs(val, key, node, soul); return;
}
if('~' === soul.slice(0,1) && 2 === (tmp = soul.slice(1)).split('.').length){ // special case, account data for a public key.
each.pub(val, key, node, soul, tmp, msg.user); return;
}
each.any(val, key, node, soul, msg.user); return;
return each.end({err: "No other data allowed!"});
};
each.alias = function(val, key, node, soul){ // Example: {_:#~@, ~@alice: {#~@alice}}
if(!val){ return each.end({err: "Data must exist!"}) } // data MUST exist
if('~@'+key === Gun.val.link.is(val)){ return check['alias'+key] = 0 } // in fact, it must be EXACTLY equal to itself
each.end({err: "Mismatching alias."}); // if it isn't, reject.
};
each.pubs = function(val, key, node, soul){ // Example: {_:#~@alice, ~asdf: {#~asdf}}
if(!val){ return each.end({err: "Alias must exist!"}) } // data MUST exist
if(key === Gun.val.link.is(val)){ return check['pubs'+soul+key] = 0 } // and the ID must be EXACTLY equal to its property
each.end({err: "Alias must match!"}); // that way nobody can tamper with the list of public keys.
};
each.pub = function(val, key, node, soul, pub, user){ // Example: {_:#~asdf, hello:SEA{'world',fdsa}}
if('pub' === key){
if(val === pub){ return (check['pub'+soul+key] = 0) } // the account MUST match `pub` property that equals the ID of the public key.
return each.end({err: "Account must match!"});
}
check['user'+soul+key] = 1;
if(user && (user = user._) && user.sea && pub === user.pub){
//var id = Gun.text.random(3);
SEA.sign(val, user.sea, function(data){ var rel;
if(u === data){ return each.end({err: SEA.err || 'Pub signature fail.'}) }
if(rel = Gun.val.link.is(val)){
(at.sea.own[rel] = at.sea.own[rel] || {})[pub] = true;
}
node[key] = data;
check['user'+soul+key] = 0;
each.end({ok: 1});
});
// TODO: Handle error!!!!
return;
}
SEA.verify(val, pub, function(data){ var rel, tmp;
if(u === data){ // make sure the signature matches the account it claims to be on.
return each.end({err: "Unverified data."}); // reject any updates that are signed with a mismatched account.
}
if((rel = Gun.val.link.is(data)) && pub === relpub(rel)){
(at.sea.own[rel] = at.sea.own[rel] || {})[pub] = true;
}
check['user'+soul+key] = 0;
each.end({ok: 1});
});
};
function relpub(s){
if(!s){ return }
s = s.split('~');
if(!s || !(s = s[1])){ return }
s = s.split('.');
if(!s || 2 > s.length){ return }
s = s.slice(0,2).join('.');
return s;
}
each.any = function(val, key, node, soul, user){ var tmp, pub;
if(!user || !(user = user._) || !(user = user.sea)){
if(tmp = relpub(soul)){
check['any'+soul+key] = 1;
SEA.verify(val, pub = tmp, function(data){ var rel;
if(!data){ return each.end({err: "Mismatched owner on '" + key + "'."}) }
if((rel = Gun.val.link.is(data)) && pub === relpub(rel)){
(at.sea.own[rel] = at.sea.own[rel] || {})[pub] = true;
}
check['any'+soul+key] = 0;
each.end({ok: 1});
});
return;
}
check['any'+soul+key] = 1;
at.on('secure', function(msg){ this.off();
check['any'+soul+key] = 0;
if(at.opt.secure){ msg = null }
each.end(msg || {err: "Data cannot be modified."});
}).on.on('secure', msg);
//each.end({err: "Data cannot be modified."});
return;
}
if(!(tmp = relpub(soul))){
if(at.opt.secure){
each.end({err: "Soul is missing public key at '" + key + "'."});
return;
}
if(val && val.slice && 'SEA{' === (val).slice(0,4)){
check['any'+soul+key] = 0;
each.end({ok: 1});
return;
}
//check['any'+soul+key] = 1;
//SEA.sign(val, user, function(data){
// if(u === data){ return each.end({err: 'Any signature failed.'}) }
// node[key] = data;
check['any'+soul+key] = 0;
each.end({ok: 1});
//});
return;
}
var pub = tmp;
if(pub !== user.pub){
each.any(val, key, node, soul);
return;
}
/*var other = Gun.obj.map(at.sea.own[soul], function(v, p){
if(user.pub !== p){ return p }
});
if(other){
each.any(val, key, node, soul);
return;
}*/
check['any'+soul+key] = 1;
SEA.sign(val, user, function(data){
if(u === data){ return each.end({err: 'My signature fail.'}) }
node[key] = data;
check['any'+soul+key] = 0;
each.end({ok: 1});
});
}
each.end = function(ctx){ // TODO: Can't you just switch this to each.end = cb?
if(each.err){ return }
if((each.err = ctx.err) || ctx.no){
console.log('NO!', each.err, msg.put);
return;
}
if(!each.end.ed){ return }
if(Gun.obj.map(check, function(no){
if(no){ return true }
})){ return }
to.next(msg);
};
Gun.obj.map(msg.put, each.node);
each.end({end: each.end.ed = true});
return; // need to manually call next after async.
}
to.next(msg); // pass forward any data we do not know how to handle or process (this allows custom security protocols).
}