fcoin/lib/bcoin/protocol/parser.js
Christopher Jeffrey 7175f81d59 fullnode
2016-02-14 18:05:37 -08:00

580 lines
12 KiB
JavaScript

/**
* parser.js - packet parser for bcoin
* Copyright (c) 2014-2015, Fedor Indutny (MIT License)
* https://github.com/indutny/bcoin
*/
var inherits = require('inherits');
var EventEmitter = require('events').EventEmitter;
var bn = require('bn.js');
var bcoin = require('../../bcoin');
var utils = bcoin.utils;
var assert = utils.assert;
var constants = require('./constants');
var network = require('./network');
/**
* Parser
*/
function Parser() {
if (!(this instanceof Parser))
return new Parser();
EventEmitter.call(this);
this.pending = [];
this.pendingTotal = 0;
this.waiting = 24;
this.packet = null;
}
inherits(Parser, EventEmitter);
Parser.prototype._error = function _error(str) {
this.emit('error', new Error(str));
};
Parser.prototype.feed = function feed(data) {
var chunk, i, off, len;
this.pendingTotal += data.length;
this.pending.push(data);
while (this.pendingTotal >= this.waiting) {
// Concat chunks
chunk = new Buffer(this.waiting);
i = 0;
off = 0;
len = 0;
for (; off < chunk.length; i++) {
len = this.pending[0].copy(chunk, off, 0, this.pending[0].length);
if (len === this.pending[0].length)
this.pending.shift();
else
this.pending[0] = this.pending[0].slice(len);
off += len;
}
assert.equal(off, chunk.length);
// Slice buffers
this.pendingTotal -= chunk.length;
this.parse(chunk);
}
};
Parser.prototype.parse = function parse(chunk) {
if (this.packet === null) {
this.packet = this.parseHeader(chunk) || {};
return;
}
this.packet.payload = chunk;
if (utils.readU32(utils.checksum(this.packet.payload)) !== this.packet.checksum)
return this._error('Invalid checksum');
this.packet.payload = this.parsePayload(this.packet.cmd, this.packet.payload);
if (this.packet.payload)
this.emit('packet', this.packet);
this.waiting = 24;
this.packet = null;
};
Parser.prototype.parseHeader = function parseHeader(h) {
var i, magic, cmd;
magic = utils.readU32(h, 0);
if (magic !== network.magic) {
return this._error('Invalid magic value: ' + magic.toString(16));
}
// Count length of the cmd
for (i = 0; h[i + 4] !== 0 && i < 12; i++);
if (i === 12)
return this._error('Not NULL-terminated cmd');
cmd = utils.stringify(h.slice(4, 4 + i));
this.waiting = utils.readU32(h, 16);
return {
cmd: cmd,
length: this.waiting,
checksum: utils.readU32(h, 20)
};
};
Parser.prototype.parsePayload = function parsePayload(cmd, p) {
if (cmd === 'version')
return this.parseVersion(p);
if (cmd === 'getdata' || cmd === 'inv' || cmd === 'notfound')
return this.parseInvList(p);
if (cmd === 'merkleblock')
return this.parseMerkleBlock(p);
if (cmd === 'headers')
return this.parseHeaders(p);
if (cmd === 'block')
return this.parseBlock(p);
if (cmd === 'tx')
return this.parseTX(p);
if (cmd === 'reject')
return this.parseReject(p);
if (cmd === 'addr')
return this.parseAddr(p);
if (cmd === 'ping')
return this.parsePing(p);
if (cmd === 'pong')
return this.parsePong(p);
return p;
};
Parser.prototype.parsePing = function parsePing(p) {
if (p.length < 8)
return this._error('pong packet is too small');
return {
nonce: utils.readU64(p, 0)
};
};
Parser.prototype.parsePong = function parsePong(p) {
if (p.length < 8)
return this._error('ping packet is too small');
return {
nonce: utils.readU64(p, 0)
};
};
Parser.prototype.parseVersion = function parseVersion(p) {
var v, services, ts, recv, from, nonce, result, off, agent, height, relay;
if (p.length < 85)
return this._error('version packet is too small');
v = utils.readU32(p, 0);
services = utils.readU64(p, 4);
// Timestamp
ts = utils.read64(p, 12);
// Our address (recv)
recv = this._parseAddr(p, 20);
// Their Address (from)
from = this._parseAddr(p, 46);
// Nonce, very dramatic
nonce = utils.readU64(p, 72);
// User agent length
result = utils.readIntv(p, 80);
off = result.off;
agent = p.slice(off, off + result.r);
off += result.r;
// Start height
height = utils.readU32(p, off);
off += 4;
// Relay
relay = p.length > off ? p[off] === 1 : true;
try {
ts = ts.toNumber();
} catch (e) {
ts = 0;
}
try {
services = services.toNumber();
} catch (e) {
services = 1;
}
return {
v: v,
services: services,
ts: ts,
local: recv,
remote: from,
nonce: nonce,
agent: utils.stringify(agent),
height: height,
relay: relay
};
};
Parser.prototype.parseInvList = function parseInvList(p) {
var items = [];
var i, off, count;
count = utils.readIntv(p, 0);
p = p.slice(count.off);
count = count.r;
if (p.length < count * 36)
return this._error('Invalid getdata size');
for (i = 0, off = 0; i < count; i++, off += 36) {
items.push({
type: constants.invByVal[utils.readU32(p, off)],
hash: utils.toArray(p.slice(off + 4, off + 36))
});
}
return items;
};
Parser.prototype.parseMerkleBlock = function parseMerkleBlock(p) {
var i, hashCount, off, hashes, flagCount, flags;
if (p.length < 86)
return this._error('Invalid merkleblock size');
hashCount = utils.readIntv(p, 84);
off = hashCount.off;
hashCount = hashCount.r;
if (off + 32 * hashCount + 1 > p.length)
return this._error('Invalid hash count');
hashes = new Array(hashCount);
for (i = 0; i < hashCount; i++)
hashes[i] = utils.toArray(p.slice(off + i * 32, off + (i + 1) * 32));
off = off + 32 * hashCount;
flagCount = utils.readIntv(p, off);
off = flagCount.off;
flagCount = flagCount.r;
if (off + flagCount > p.length)
return this._error('Invalid flag count');
flags = utils.toArray(p.slice(off, off + flagCount));
return {
version: utils.read32(p, 0),
prevBlock: utils.toArray(p.slice(4, 36)),
merkleRoot: utils.toArray(p.slice(36, 68)),
ts: utils.readU32(p, 68),
bits: utils.readU32(p, 72),
nonce: utils.readU32(p, 76),
totalTX: utils.readU32(p, 80),
hashes: hashes,
flags: flags,
_raw: p,
_size: p.length
};
};
Parser.prototype.parseHeaders = function parseHeaders(p) {
var headers = [];
var i, result, off, count, header, start, r;
if (p.length < 81)
return this._error('Invalid headers size');
result = utils.readIntv(p, 0);
off = result.off;
count = result.r;
if (p.length < count * 80)
return this._error('Invalid headers size');
for (i = 0; i < count; i++) {
header = {};
start = off;
header.version = utils.read32(p, off);
off += 4;
header.prevBlock = utils.toArray(p.slice(off, off + 32));
off += 32;
header.merkleRoot = utils.toArray(p.slice(off, off + 32));
off += 32;
header.ts = utils.readU32(p, off);
off += 4;
header.bits = utils.readU32(p, off);
off += 4;
header.nonce = utils.readU32(p, off);
off += 4;
r = utils.readIntv(p, off);
header.totalTX = r.r;
off = r.off;
header._raw = p.slice(start, start + 80);
headers.push(header);
}
return headers;
};
Parser.prototype.parseBlock = function parseBlock(p) {
var txs = [];
var i, result, off, totalTX, tx;
if (p.length < 81)
return this._error('Invalid block size');
result = utils.readIntv(p, 80);
off = result.off;
totalTX = result.r;
for (i = 0; i < totalTX; i++) {
tx = this.parseTX(p.slice(off));
if (!tx)
return this._error('Invalid tx count for block');
tx._offset = off;
off += tx._size;
txs.push(tx);
}
return {
version: utils.read32(p, 0),
prevBlock: utils.toArray(p.slice(4, 36)),
merkleRoot: utils.toArray(p.slice(36, 68)),
ts: utils.readU32(p, 68),
bits: utils.readU32(p, 72),
nonce: utils.readU32(p, 76),
totalTX: totalTX,
txs: txs,
_raw: p,
_size: p.length
};
};
Parser.prototype.parseTXIn = function parseTXIn(p) {
var scriptLen, off;
if (p.length < 41)
return this._error('Invalid tx_in size');
scriptLen = utils.readIntv(p, 36);
off = scriptLen.off;
scriptLen = scriptLen.r;
if (off + scriptLen + 4 > p.length)
return this._error('Invalid tx_in script length');
return {
_size: off + scriptLen + 4,
prevout: {
hash: utils.toArray(p.slice(0, 32)),
index: utils.readU32(p, 32)
},
script: bcoin.script.decode(utils.toArray(p.slice(off, off + scriptLen))),
sequence: utils.readU32(p, off + scriptLen)
};
};
Parser.prototype.parseTXOut = function parseTXOut(p) {
var scriptLen, off;
if (p.length < 9)
return this._error('Invalid tx_out size');
scriptLen = utils.readIntv(p, 8);
off = scriptLen.off;
scriptLen = scriptLen.r;
if (off + scriptLen > p.length)
return this._error('Invalid tx_out script length');
return {
_size: off + scriptLen,
value: utils.read64(p, 0),
script: bcoin.script.decode(utils.toArray(p.slice(off, off + scriptLen)))
};
};
Parser.prototype.parseTX = function parseTX(p) {
var inCount, off, txIn, tx;
var outCount, txOut;
var i;
if (p.length < 10)
return this._error('Invalid tx size');
inCount = utils.readIntv(p, 4);
off = inCount.off;
inCount = inCount.r;
if (inCount < 0)
return this._error('Invalid tx_in count (negative)');
if (off + 41 * inCount + 5 > p.length)
return this._error('Invalid tx_in count (too big)');
txIn = new Array(inCount);
for (i = 0; i < inCount; i++) {
tx = this.parseTXIn(p.slice(off));
if (!tx)
return;
txIn[i] = tx;
tx._offset = off;
off += tx._size;
if (off + 5 > p.length)
return this._error('Invalid tx_in offset');
}
outCount = utils.readIntv(p, off);
off = outCount.off;
outCount = outCount.r;
if (outCount < 0)
return this._error('Invalid tx_out count (negative)');
if (off + 9 * outCount + 4 > p.length)
return this._error('Invalid tx_out count (too big)');
txOut = new Array(outCount);
for (i = 0; i < outCount; i++) {
tx = this.parseTXOut(p.slice(off));
if (!tx)
return;
txOut[i] = tx;
tx._offset = off;
off += tx._size;
if (off + 4 > p.length)
return this._error('Invalid tx_out offset');
}
return {
_raw: p.slice(0, off + 4),
version: utils.read32(p, 0),
inputs: txIn,
outputs: txOut,
locktime: utils.readU32(p, off),
_size: off + 4
};
};
Parser.prototype.parseReject = function parseReject(p) {
var messageLen, off, message, ccode, reasonLen, reason, data;
if (p.length < 3)
return this._error('Invalid reject size');
messageLen = utils.readIntv(p, 0);
off = messageLen.off;
messageLen = messageLen.r;
if (off + messageLen + 2 > p.length)
return this._error('Invalid reject message');
message = utils.stringify(p.slice(off, off + messageLen));
off += messageLen;
ccode = utils.readU8(p, off);
off++;
reasonLen = utils.readIntv(p, off);
off = reasonLen.off;
reasonLen = reasonLen.r;
if (off + reasonLen > p.length)
return this._error('Invalid reject reason');
reason = utils.stringify(p.slice(off, off + reasonLen));
off += reasonLen;
data = utils.toArray(p.slice(off, off + 32));
return {
message: message,
ccode: constants.rejectByVal[ccode] || ccode,
reason: reason,
data: data
};
};
Parser.prototype._parseAddr = function _parseAddr(p, off, full) {
var ts, services, ip, port;
if (!off)
off = 0;
if (full) {
ts = utils.readU32(p, off);
off += 4;
} else {
ts = 0;
}
services = utils.readU64(p, off);
off += 8;
ip = utils.toArray(p.slice(off, off + 16));
off += 16;
port = utils.readU16BE(p, off);
off += 2;
try {
services = services.toNumber();
} catch (e) {
services = 1;
}
return {
ts: ts,
services: services,
ipv6: utils.array2ip(ip, 6),
ipv4: utils.array2ip(ip, 4),
port: port
};
};
Parser.prototype.parseAddr = function parseAddr(p) {
if (p.length < 31)
return this._error('Invalid addr size');
var addrs = [];
var i, off, count;
count = utils.readIntv(p, 0);
off = count.off;
count = count.r;
for (i = 0; i < count && off < p.length; i++) {
addrs.push(this._parseAddr(p, off, true));
off += 30;
}
return addrs;
};
Parser.prototype.parseMempool = function parseMempool(p) {
if (p.length > 0)
return this._error('Invalid mempool size');
return {};
};
/**
* Expose
*/
module.exports = Parser;