better system to prevent DOSing.

lib/bcoin/block.js

@@ -489,7 +489,7 @@ Block.prototype.verifyContext = function verifyContext() {
 };
 
 Block.prototype.isGenesis = function isGenesis() {
-  return this.hash('hex') === utils.toHex(network.genesis._hash);
+  return this.hash('hex') === network.genesis.hash;
 };
 
 Block.prototype.getHeight = function getHeight() {

lib/bcoin/chain.js

@@ -56,9 +56,9 @@ function Chain(options) {
     network: network.type,
     entries: [
       {
-        hash: utils.toHex(network.genesis._hash),
+        hash: network.genesis.hash,
         version: network.genesis.version,
-        prevBlock: utils.toHex(network.genesis.prevBlock),
+        prevBlock: network.genesis.prevBlock,
         ts: network.genesis.ts,
         bits: network.genesis.bits,
         height: 0
@@ -302,9 +302,8 @@ Chain.prototype.add = function add(block, peer) {
       code = Chain.codes.invalid;
       this.emit('invalid', {
         height: prevHeight + 1,
-        hash: hash,
+        hash: hash
-        peer: peer
+      }, peer);
-      });
       break;
     }
 
@@ -322,9 +321,8 @@ Chain.prototype.add = function add(block, peer) {
           height: -1,
           expected: this.orphan.map[prevHash].hash('hex'),
           received: hash,
-          checkpoint: null,
+          checkpoint: null
-          peer: peer
+        }, peer);
-        });
         code = Chain.codes.forked;
         break;
       }
@@ -383,9 +381,8 @@ Chain.prototype.add = function add(block, peer) {
           height: prevHeight + 1,
           expected: tip.hash,
           received: hash,
-          checkpoint: null,
+          checkpoint: null
-          peer: peer
+        }, peer);
-        });
         code = Chain.codes.forked;
         break;
       }
@@ -397,9 +394,8 @@ Chain.prototype.add = function add(block, peer) {
         code = Chain.codes.invalid;
         this.emit('invalid', {
           height: prevHeight + 1,
-          hash: hash,
+          hash: hash
-          peer: peer
+        }, peer);
-        });
         break;
       }
 
@@ -422,8 +418,7 @@ Chain.prototype.add = function add(block, peer) {
           height: entry.height,
           expected: network.checkpoints[entry.height],
           received: entry.hash,
-          checkpoint: true,
+          checkpoint: true
-          peer: peer
         });
         break;
       }
@@ -483,17 +478,14 @@ Chain.prototype.add = function add(block, peer) {
   return total;
 };
 
-Chain.prototype.has = function has(hash, cb) {
+Chain.prototype.has = function has(hash) {
-  if (this.loading) {
+  if (this.hasBlock(hash))
-    this.once('load', function() {
+    return true;
-      this.has(hash, noIndex, cb);
-    });
-    return;
-  }
 
-  cb = utils.asyncify(cb);
+  if (this.hasOrphan(hash))
+    return true;
 
-  return cb(this.hasBlock(hash) || this.hasOrphan(hash));
+  return false;
 };
 
 Chain.prototype.byHeight = function byHeight(height) {

lib/bcoin/peer.js

@@ -113,7 +113,7 @@ Peer.prototype._init = function init() {
 
   this.socket.once('error', function(err) {
     self._error(err);
-    self.emit('misbehave');
+    self.pool.misbehaving(self, 100);
   });
 
   this.socket.once('close', function() {
@@ -134,7 +134,7 @@ Peer.prototype._init = function init() {
     // Something is wrong here.
     // Ignore this peer.
     self.destroy();
-    self.emit('misbehave');
+    self.pool.misbehaving(self, 100);
   });
 
   if (this.pool.options.fullNode) {
@@ -156,7 +156,7 @@ Peer.prototype._init = function init() {
     if (err) {
       self._error(err);
       self.destroy();
-      self.emit('misbehave');
+      self.pool.misbehaving(self, 100);
       return;
     }
     self.ack = true;

lib/bcoin/pool.js

@@ -12,6 +12,7 @@ var bcoin = require('../bcoin');
 var utils = bcoin.utils;
 var assert = utils.assert;
 var network = bcoin.protocol.network;
+var constants = bcoin.protocol.constants;
 
 /**
  * Pool
@@ -40,9 +41,6 @@ function Pool(options) {
 
   this.originalSeeds = (options.seeds || network.seeds).map(utils.parseHost);
   this.setSeeds([]);
-  this._priorityTries = {};
-  this._regularTries = {};
-  this._misbehaving = {};
 
   this.storage = this.options.storage;
   this.destroyed = false;
@@ -112,13 +110,21 @@ function Pool(options) {
     // Peers that are loading block ids
     load: null,
     // All peers
-    all: []
+    all: [],
+    // Misbehaving hosts
+    misbehaving: {},
+    // Attempts at using seed peers
+    tries: {
+      priority: {},
+      regular: {}
+    }
   };
 
   this.block = {
     bestHeight: 0,
     bestHash: null,
-    type: this.options.fullNode ? 'block' : 'filtered'
+    type: this.options.fullNode ? 'block' : 'filtered',
+    invalid: {}
   };
 
   this.request = {
@@ -179,36 +185,36 @@ Pool.prototype._init = function _init() {
     self.emit('block', block, peer);
   });
 
-  this.chain.on('fork', function(data) {
+  this.chain.on('fork', function(data, peer) {
     self.emit('debug',
       'Fork at height %d: expected=%s received=%s checkpoint=%s peer=%s',
       data.height,
       utils.revHex(data.expected),
       utils.revHex(data.received),
       data.checkpoint,
-      data.peer ? data.peer.host : ''
+      peer ? peer.host : ''
     );
 
-    if (!data.peer)
+    if (!peer)
       return;
 
-    data.peer.destroy();
+    self.misbehaving(peer, 100);
   });
 
-  this.chain.on('invalid', function(data) {
+  this.chain.on('invalid', function(data, peer) {
     self.emit('debug',
       'Invalid block at height: %d: hash=%s peer=%s',
       data.height,
       utils.revHex(data.hash),
-      data.peer ? data.peer.host : ''
+      peer ? peer.host : ''
     );
 
-    if (!data.peer)
+    self.block.invalid[data.hash] = true;
+
+    if (!peer)
       return;
 
-    // We should technically use a ban score
+    self.misbehaving(peer, 100);
-    // here instead of killing the peer.
-    data.peer.destroy();
   });
 
   this.options.wallets.forEach(function(w) {
@@ -536,10 +542,12 @@ Pool.prototype._handleInv = function _handleInv(hashes, peer) {
 
 Pool.prototype._handleBlock = function _handleBlock(block, peer) {
   var self = this;
+  var requested, hasPrev;
 
-  var requested = this._response(block);
+  // Fulfill our request.
+  requested = this._response(block);
 
-  // Emulate bip37 - emit all the "watched" txs
+  // Emulate BIP37: emit all the filtered transactions.
   if (this.options.fullNode && this.listeners('watched').length > 0) {
     block.txs.forEach(function(tx) {
       if (self.isWatched(tx))
@@ -547,21 +555,39 @@ Pool.prototype._handleBlock = function _handleBlock(block, peer) {
     });
   }
 
-  // Ignore if we already have
+  // Ensure the block was not invalid last time.
-  if (this.chain.has(block)) {
+  // Someone might be sending us bad blocks to DoS us.
-    this.emit('debug', 'Already have block %s (%s)', block.height, peer.host);
+  if (this.block.invalid[block.hash('hex')]) {
+    this.misbehaving(peer, 100);
     return false;
   }
 
-  // Make sure the block is valid
+  // Ensure this is not a continuation
+  // of an invalid chain.
+  if (this.block.invalid[block.prevBlock]) {
+    this.misbehaving(peer, 100);
+    return false;
+  }
+
+  // Ignore if we already have.
+  if (this.chain.has(block)) {
+    this.emit('debug', 'Already have block %s (%s)', block.height, peer.host);
+    this.misbehaving(peer, 1);
+    return false;
+  }
+
+  // Make sure the block is valid.
   if (!block.verify()) {
     this.emit('debug',
       'Block verification failed for %s (%s)',
       block.rhash, peer.host);
+    this.block.invalid[block.hash('hex')] = true;
+    this.misbehaving(peer, 100);
     return false;
   }
 
-  // Someone is sending us blocks without us requesting them.
+  // Someone is sending us blocks without
+  // us requesting them.
   if (!requested) {
     this.emit('debug',
       'Recieved unrequested block: %s (%s)',
@@ -571,19 +597,40 @@ Pool.prototype._handleBlock = function _handleBlock(block, peer) {
   // Resolve orphan chain
   if (!this.options.headers) {
     if (!this.chain.hasBlock(block.prevBlock)) {
+      // Special case for genesis block.
+      if (block.isGenesis())
+        return false;
+
+      // Make sure the peer doesn't send us
+      // more than 100 orphans every 3 minutes.
+      if (this.orphaning(peer)) {
+        this.misbehaving(peer, 100);
+        return false;
+      }
+
       // NOTE: If we were to emit new orphans here, we
       // would not need to store full blocks as orphans.
       // However, the listener would not be able to see
       // the height until later.
       if (this._addIndex(block, peer))
         this.emit('pool block', block, peer);
+
       this.peers.load.loadBlocks(
         this.chain.locatorHashes(),
         this.chain.getOrphanRoot(block)
       );
+
       this.emit('debug', 'Handled orphan %s (%s)', block.rhash, peer.host);
+
       return false;
     }
+  } else {
+    if (!this.chain.hasBlock(block.prevBlock)) {
+      if (!this.options.multiplePeers) {
+        if (this.misbehaving(peer, 10))
+          return false;
+      }
+    }
   }
 
   // Add to index and emit/save
@@ -688,10 +735,6 @@ Pool.prototype._createPeer = function _createPeer(backoff, priority) {
     self.emit.apply(self, ['debug'].concat(args));
   });
 
-  peer.once('misbehave', function() {
-    self._misbehaving[peer.host] = true;
-  });
-
   peer.on('reject', function(payload) {
     var data = utils.revHex(utils.toHex(payload.data));
 
@@ -1203,37 +1246,31 @@ Pool.prototype.search = function search(id, range, e) {
 };
 
 Pool.prototype._request = function _request(type, hash, options, cb) {
-  var self = this;
-
-  // Optional `force`
   if (typeof options === 'function') {
     cb = options;
     options = {};
   }
+
   if (!options)
     options = {};
 
   hash = utils.toHex(hash);
+
   if (this.request.map[hash])
     return this.request.map[hash].addCallback(cb);
 
-  function next(has) {
-    if (has)
-      return;
-
-    if (self.destroyed)
-      return;
-
-    var req = new LoadRequest(self, type, hash, cb);
-    req.add(options.noQueue);
-  }
-
   // Block should be not in chain, or be requested
   // Do not use with headers-first
-  if (!options.force && (type === 'block' || type === 'filtered'))
+  if (!options.force && (type === 'block' || type === 'filtered')) {
-    return this.chain.has(hash, next);
+    if (this.chain.has(hash))
+      return;
+  }
 
-  return next(false);
+  if (this.destroyed)
+    return;
+
+  var req = new LoadRequest(this, type, hash, cb);
+  req.add(options.noQueue);
 };
 
 Pool.prototype._response = function _response(entity) {
@@ -1498,7 +1535,10 @@ Pool.prototype.usableSeed = function usableSeed(priority, connecting) {
   var i, addr;
   var original = this.originalSeeds;
   var seeds = this.seeds;
-  var tries = priority ? this._priorityTries : this._regularTries;
+  var tries = this.peers.tries.regular;
+
+  if (priority)
+    tries = this.peers.tries.priority;
 
   // Hang back if we don't have a loader peer yet.
   if (!connecting && !priority && (!this.peers.load || !this.peers.load.socket))
@@ -1516,7 +1556,7 @@ Pool.prototype.usableSeed = function usableSeed(priority, connecting) {
     assert(addr.host);
     if (this.getPeer(addr))
       continue;
-    if (this._misbehaving[addr.host])
+    if (this.isMisbehaving(addr.host))
       continue;
     if (tries[addr.host])
       continue;
@@ -1533,7 +1573,7 @@ Pool.prototype.usableSeed = function usableSeed(priority, connecting) {
       assert(addr.host);
       if (this.peers.load && this.getPeer(addr) === this.peers.load)
         continue;
-      if (this._misbehaving[addr.host])
+      if (this.isMisbehaving(addr.host))
         continue;
       if (tries[addr.host])
         continue;
@@ -1549,7 +1589,7 @@ Pool.prototype.usableSeed = function usableSeed(priority, connecting) {
     assert(addr.host);
     if (this.getPeer(addr))
       continue;
-    if (this._misbehaving[addr.host])
+    if (this.isMisbehaving(addr.host))
       continue;
     return addr;
   }
@@ -1562,7 +1602,7 @@ Pool.prototype.usableSeed = function usableSeed(priority, connecting) {
       assert(addr.host);
       if (this.peers.load && this.getPeer(addr) === this.peers.load)
         continue;
-      if (this._misbehaving[addr.host])
+      if (this.isMisbehaving(addr.host))
         continue;
       return addr;
     }
@@ -1622,6 +1662,64 @@ Pool.prototype.removeSeed = function removeSeed(seed) {
   return true;
 };
 
+Pool.prototype.orphaning = function orphaning(peer) {
+  if (!peer._orphanTime)
+    peer._orphanTime = utils.now();
+
+  if (!peer._orphans)
+    peer._orphans = 0;
+
+  if (utils.now() > peer._orphanTime + 3 * 60) {
+    peer._orphans = 0;
+    peer._orphanTime = utils.now();
+  }
+
+  peer._orphans += 1;
+
+  if (peer._orphans > 100)
+    return true;
+
+  return false;
+};
+
+Pool.prototype.misbehaving = function misbehaving(peer, dos) {
+  if (!peer._banscore)
+    peer._banscore = 0;
+
+  peer._banscore += dos;
+
+  if (peer._banscore >= constants.banScore) {
+    this.peers.misbehaving[peer.host] = utils.now();
+    this.emit('debug', 'Ban threshold exceeded for %s', peer.host);
+    peer.destroy();
+    return true;
+  }
+
+  return false;
+};
+
+Pool.prototype.isMisbehaving = function isMisbehaving(host) {
+  var peer, time;
+
+  if (host.host)
+    host = host.host;
+
+  time = this.peers.misbehaving[host];
+
+  if (time) {
+    if (utils.now() > time + constants.banTime) {
+      delete this.peers.misbehaving[host];
+      peer = this.getPeer(host);
+      if (peer)
+        peer._banscore = 0;
+      return false;
+    }
+    return true;
+  }
+
+  return false;
+};
+
 Pool.prototype.toJSON = function toJSON() {
   return {
     v: 1,

lib/bcoin/protocol/constants.js

@@ -262,3 +262,6 @@ exports.userAgent = '/bcoin:' + exports.userVersion + '/';
 exports.coin = new bn(10000000).muln(10);
 exports.cent = new bn(1000000);
 exports.maxMoney = new bn(21000000).mul(exports.coin);
+
+exports.banTime = 24 * 60 * 60;
+exports.banScore = 100;

lib/bcoin/protocol/network.js

@@ -88,18 +88,17 @@ main.halvingInterval = 210000;
 // http://blockexplorer.com/rawblock/000000000019d6689c085ae165831e934ff763ae46a2a6c172b3f1b60a8ce26f
 main.genesis = {
   version: 1,
-  _hash: utils.toArray(
+  hash: utils.revHex(
-    '000000000019d6689c085ae165831e934ff763ae46a2a6c172b3f1b60a8ce26f',
+    '000000000019d6689c085ae165831e934ff763ae46a2a6c172b3f1b60a8ce26f'
-    'hex'
+  ),
-  ).reverse(),
+  prevBlock: utils.toHex(
-  prevBlock: [ 0, 0, 0, 0, 0, 0, 0, 0,
+             [ 0, 0, 0, 0, 0, 0, 0, 0,
                0, 0, 0, 0, 0, 0, 0, 0,
                0, 0, 0, 0, 0, 0, 0, 0,
-               0, 0, 0, 0, 0, 0, 0, 0 ],
+               0, 0, 0, 0, 0, 0, 0, 0 ]),
-  merkleRoot: utils.toArray(
+  merkleRoot: utils.revHex(
-    '4a5e1e4baab89f3a32518a88c31bc87f618f76673e2cc77ab2127b7afdeda33b',
+    '4a5e1e4baab89f3a32518a88c31bc87f618f76673e2cc77ab2127b7afdeda33b'
-    'hex'
+  ),
-  ).reverse(),
   ts: 1231006505,
   bits: 0x1d00ffff,
   nonce: 2083236893
@@ -113,9 +112,9 @@ main.preload = {
   network: main.type,
   entries: [
     {
-      hash: utils.toHex(main.genesis._hash),
+      hash: main.genesis.hash,
       version: main.genesis.version,
-      prevBlock: utils.toHex(main.genesis.prevBlock),
+      prevBlock: main.genesis.prevBlock,
       ts: main.genesis.ts,
       bits: main.genesis.bits,
       height: 0
@@ -203,18 +202,17 @@ testnet.halvingInterval = 210000;
 // http://blockexplorer.com/testnet/rawblock/000000000933ea01ad0ee984209779baaec3ced90fa3f408719526f8d77f4943
 testnet.genesis =  {
   version: 1,
-  _hash: utils.toArray(
+  hash: utils.revHex(
-    '000000000933ea01ad0ee984209779baaec3ced90fa3f408719526f8d77f4943',
+    '000000000933ea01ad0ee984209779baaec3ced90fa3f408719526f8d77f4943'
-    'hex'
+  ),
-  ).reverse(),
+  prevBlock: utils.toHex(
-  prevBlock: [ 0, 0, 0, 0, 0, 0, 0, 0,
+             [ 0, 0, 0, 0, 0, 0, 0, 0,
                0, 0, 0, 0, 0, 0, 0, 0,
                0, 0, 0, 0, 0, 0, 0, 0,
-               0, 0, 0, 0, 0, 0, 0, 0 ],
+               0, 0, 0, 0, 0, 0, 0, 0 ]),
-  merkleRoot: utils.toArray(
+  merkleRoot: utils.revHex(
-    '4a5e1e4baab89f3a32518a88c31bc87f618f76673e2cc77ab2127b7afdeda33b',
+    '4a5e1e4baab89f3a32518a88c31bc87f618f76673e2cc77ab2127b7afdeda33b'
-    'hex'
+  ),
-  ).reverse(),
   ts: 1296688602,
   bits: 0x1d00ffff,
   nonce: 414098458
@@ -228,9 +226,9 @@ testnet.preload = {
   network: testnet.type,
   entries: [
     {
-      hash: utils.toHex(testnet.genesis._hash),
+      hash: testnet.genesis.hash,
       version: testnet.genesis.version,
-      prevBlock: utils.toHex(testnet.genesis.prevBlock),
+      prevBlock: testnet.genesis.prevBlock,
       ts: testnet.genesis.ts,
       bits: testnet.genesis.bits,
       height: 0
@@ -300,18 +298,17 @@ regtest.halvingInterval = 150;
 
 regtest.genesis =  {
   version: 1,
-  _hash: utils.toArray(
+  hash: utils.revHex(
-    '0f9188f13cb7b2c71f2a335e3a4fc328bf5beb436012afca590b1a11466e2206',
+    '0f9188f13cb7b2c71f2a335e3a4fc328bf5beb436012afca590b1a11466e2206'
-    'hex'
+  ),
-  ).reverse(),
+  prevBlock: utils.toHex(
-  prevBlock: [ 0, 0, 0, 0, 0, 0, 0, 0,
+             [ 0, 0, 0, 0, 0, 0, 0, 0,
                0, 0, 0, 0, 0, 0, 0, 0,
                0, 0, 0, 0, 0, 0, 0, 0,
-               0, 0, 0, 0, 0, 0, 0, 0 ],
+               0, 0, 0, 0, 0, 0, 0, 0 ]),
-  merkleRoot: utils.toArray(
+  merkleRoot: utils.revHex(
-    '4a5e1e4baab89f3a32518a88c31bc87f618f76673e2cc77ab2127b7afdeda33b',
+    '4a5e1e4baab89f3a32518a88c31bc87f618f76673e2cc77ab2127b7afdeda33b'
-    'hex'
+  ),
-  ).reverse(),
   ts: 1296688602,
   bits: 0x207fffff,
   nonce: 2
@@ -325,9 +322,9 @@ regtest.preload = {
   network: regtest.type,
   entries: [
     {
-      hash: utils.toHex(regtest.genesis._hash),
+      hash: regtest.genesis.hash,
       version: regtest.genesis.version,
-      prevBlock: utils.toHex(regtest.genesis.prevBlock),
+      prevBlock: regtest.genesis.prevBlock,
       ts: regtest.genesis.ts,
       bits: regtest.genesis.bits,
       height: 0