391 lines
11 KiB
JavaScript
391 lines
11 KiB
JavaScript
/**
|
|
* Working with messages.
|
|
* @see {@link https://bitmessage.org/wiki/Protocol_specification#Message_types}
|
|
* @see {@link https://bitmessage.org/wiki/Protocol_specification_v3#Message_types}
|
|
* @see {@link https://bitmessage.org/Bitmessage%20Technical%20Paper.pdf}
|
|
* @module bitmessage/messages
|
|
*/
|
|
// TODO(Kagami): Document object-like params.
|
|
|
|
"use strict";
|
|
|
|
var objectAssign = Object.assign || require("object-assign");
|
|
var assert = require("./_util").assert;
|
|
var structs = require("./structs");
|
|
var UserAgent = require("./user-agent");
|
|
var util = require("./_util");
|
|
|
|
var message = structs.message;
|
|
var ServicesBitfield = structs.ServicesBitfield;
|
|
|
|
/**
|
|
* Try to get command for the given encoded message.
|
|
* Note that this function doesn't do any validation because it is
|
|
* already provided by `message.decode` routine. Normally you call this
|
|
* for each incoming message and then call decode function of the
|
|
* appropriate message handler.
|
|
* @param {Buffer} buf - Buffer that starts with encoded message
|
|
* @return {?string} Message's command if any
|
|
*/
|
|
exports.getCommand = function(buf) {
|
|
if (buf.length < 16) {
|
|
return;
|
|
}
|
|
var command = buf.slice(4, 16);
|
|
var firstNonNull = 0;
|
|
for (var i = 11; i >=0; i--) {
|
|
if (command[i] !== 0) {
|
|
firstNonNull = i + 1;
|
|
break;
|
|
}
|
|
}
|
|
return command.slice(0, firstNonNull).toString("ascii");
|
|
};
|
|
|
|
/**
|
|
* `version` message.
|
|
* @see {@link https://bitmessage.org/wiki/Protocol_specification#version}
|
|
* @namespace
|
|
* @static
|
|
*/
|
|
var version = exports.version = {
|
|
/** Random nonce used to detect connections to self. */
|
|
NONCE: new Buffer("20bde0a3355dad78", "hex"),
|
|
|
|
/**
|
|
* Decode `version` message.
|
|
* NOTE: `nonce` is copied.
|
|
* @param {Buffer} buf - Message
|
|
* @return {Object} Decoded `version` structure.
|
|
*/
|
|
decode: function(buf) {
|
|
var decoded = message.decode(buf);
|
|
assert(decoded.command === "version", "Bad command");
|
|
return version.decodePayload(decoded.payload);
|
|
},
|
|
|
|
/**
|
|
* Decode `version` message payload.
|
|
* NOTE: `nonce` is copied.
|
|
* @param {Buffer} buf - Message payload
|
|
* @return {Object} Decoded `version` structure.
|
|
*/
|
|
decodePayload: function(buf) {
|
|
// 4 + 8 + 8 + 26 + 26 + 8 + (1+) + (1+)
|
|
assert(buf.length >= 82, "Buffer is too small");
|
|
var protoVersion = buf.readUInt32BE(0, true);
|
|
var services = ServicesBitfield(buf.slice(4, 12), {copy: true});
|
|
var time = util.readTime64BE(buf, 12);
|
|
var short = {short: true};
|
|
var addrRecv = structs.net_addr.decode(buf.slice(20, 46), short);
|
|
var addrFrom = structs.net_addr.decode(buf.slice(46, 72), short);
|
|
var nonce = new Buffer(8);
|
|
buf.copy(nonce, 0, 72, 80);
|
|
var decodedUa = UserAgent.decode(buf.slice(80));
|
|
var decodedStreamNumbers = structs.var_int_list.decode(decodedUa.rest);
|
|
return {
|
|
version: protoVersion,
|
|
services: services,
|
|
time: time,
|
|
remoteHost: addrRecv.host,
|
|
remotePort: addrRecv.port,
|
|
port: addrFrom.port,
|
|
nonce: nonce,
|
|
userAgent: decodedUa.str,
|
|
streamNumbers: decodedStreamNumbers.list,
|
|
// NOTE(Kagami): Real data length. It may be some gap between end
|
|
// of stream numbers list and end of payload:
|
|
// [payload..............[stream numbers]xxxx]
|
|
// We are currently ignoring that.
|
|
length: 80 + decodedUa.length + decodedStreamNumbers.length,
|
|
};
|
|
},
|
|
|
|
/**
|
|
* Encode `version` message.
|
|
* @param {Object} opts - Version options
|
|
* @return {Buffer} Encoded message.
|
|
*/
|
|
encode: function(opts) {
|
|
var payload = version.encodePayload(opts);
|
|
return message.encode("version", payload);
|
|
},
|
|
|
|
/**
|
|
* Encode `version` message payload.
|
|
* @param {Object} opts - Version options
|
|
* @return {Buffer} Encoded payload.
|
|
*/
|
|
encodePayload: function(opts) {
|
|
// Deal with default options.
|
|
var services = opts.services ||
|
|
ServicesBitfield().set(ServicesBitfield.NODE_NETWORK);
|
|
var time = opts.time || new Date();
|
|
var nonce = opts.nonce || version.NONCE;
|
|
assert(nonce.length === 8, "Bad nonce");
|
|
var userAgent = opts.userAgent || UserAgent.SELF;
|
|
var streamNumbers = opts.streamNumbers || [1];
|
|
// Start encoding.
|
|
var protoVersion = new Buffer(4);
|
|
protoVersion.writeUInt32BE(util.PROTOCOL_VERSION, 0);
|
|
var addrRecv = structs.net_addr.encode({
|
|
services: services,
|
|
host: opts.remoteHost,
|
|
port: opts.remotePort,
|
|
short: true,
|
|
});
|
|
var addrFrom = structs.net_addr.encode({
|
|
services: services,
|
|
host: "127.0.0.1",
|
|
port: opts.port,
|
|
short: true,
|
|
});
|
|
return Buffer.concat([
|
|
protoVersion,
|
|
services.buffer,
|
|
util.writeTime64BE(null, time),
|
|
addrRecv,
|
|
addrFrom,
|
|
nonce,
|
|
UserAgent.encode(userAgent),
|
|
structs.var_int_list.encode(streamNumbers),
|
|
]);
|
|
},
|
|
};
|
|
|
|
/**
|
|
* `addr` message. Provide information on known nodes of the network.
|
|
* @see {@link https://bitmessage.org/wiki/Protocol_specification#addr}
|
|
* @namespace
|
|
* @static
|
|
*/
|
|
var addr = exports.addr = {
|
|
/**
|
|
* Decode `addr` message.
|
|
* @param {Buffer} buf - Message
|
|
* @return {Object} Decoded `addr` structure.
|
|
*/
|
|
decode: function(buf) {
|
|
var decoded = message.decode(buf);
|
|
assert(decoded.command === "addr", "Bad command");
|
|
return addr.decodePayload(decoded.payload);
|
|
},
|
|
|
|
/**
|
|
* Decode `addr` message payload.
|
|
* @param {Buffer} buf - Message payload
|
|
* @return {Object} Decoded `addr` structure.
|
|
*/
|
|
decodePayload: function(buf) {
|
|
var decoded = structs.var_int.decode(buf);
|
|
var listLength = decoded.value;
|
|
assert(listLength <= 1000, "Too many address entires");
|
|
var length = decoded.length + listLength * 38;
|
|
assert(buf.length >= length, "Buffer is too small");
|
|
var rest = decoded.rest;
|
|
var addrs = new Array(listLength);
|
|
for (var i = 0; i < listLength; i++) {
|
|
addrs[i] = structs.net_addr.decode(rest.slice(i*38, (i+1)*38));
|
|
}
|
|
return {
|
|
addrs: addrs,
|
|
// Real data length.
|
|
length: length,
|
|
};
|
|
},
|
|
|
|
/**
|
|
* Encode `addr` message.
|
|
* @param {Object[]} addrs - Network addresses
|
|
* @return {Buffer} Encoded message.
|
|
*/
|
|
encode: function(addrs) {
|
|
var payload = addr.encodePayload(addrs);
|
|
return message.encode("addr", payload);
|
|
},
|
|
|
|
/**
|
|
* Encode `addr` message payload.
|
|
* @param {Object[]} addrs - Network addresses
|
|
* @return {Buffer} Encoded payload.
|
|
*/
|
|
encodePayload: function(addrs) {
|
|
assert(addrs.length <= 1000, "Too many address entires");
|
|
var addrsBuf = Buffer.concat(addrs.map(structs.net_addr.encode));
|
|
return Buffer.concat([structs.var_int.encode(addrs.length), addrsBuf]);
|
|
},
|
|
};
|
|
|
|
/**
|
|
* `inv` message. Allows a node to advertise its knowledge of one or
|
|
* more objects.
|
|
* @see {@link https://bitmessage.org/wiki/Protocol_specification#inv}
|
|
* @namespace
|
|
* @static
|
|
*/
|
|
var inv = exports.inv = {
|
|
/**
|
|
* Decode `inv` message.
|
|
* @param {Buffer} buf - Message
|
|
* @return {Object} Decoded `inv` structure.
|
|
*/
|
|
decode: function(buf) {
|
|
var decoded = message.decode(buf);
|
|
assert(decoded.command === "inv", "Bad command");
|
|
return inv.decodePayload(decoded.payload);
|
|
},
|
|
|
|
/**
|
|
* Decode `inv` message payload.
|
|
* @param {Buffer} buf - Message payload
|
|
* @return {Object} Decoded `inv` structure.
|
|
*/
|
|
decodePayload: function(buf) {
|
|
var decoded = structs.var_int.decode(buf);
|
|
var listLength = decoded.value;
|
|
assert(listLength <= 50000, "Too many inventory entires");
|
|
var length = decoded.length + listLength * 32;
|
|
assert(buf.length >= length, "Buffer is too small");
|
|
var rest = decoded.rest;
|
|
var inventory = new Array(listLength);
|
|
for (var i = 0; i < listLength; i++) {
|
|
inventory[i] = rest.slice(i*32, (i+1)*32);
|
|
}
|
|
return {
|
|
inventory: inventory,
|
|
// Real data length.
|
|
length: length,
|
|
};
|
|
},
|
|
|
|
/**
|
|
* Encode `inv` message.
|
|
* @param {Buffer[]} inventory - Inventory vector list (encoded)
|
|
* @return {Buffer} Encoded message.
|
|
*/
|
|
encode: function(inventory) {
|
|
var payload = inv.encodePayload(inventory);
|
|
return message.encode("inv", payload);
|
|
},
|
|
|
|
/**
|
|
* Encode `inv` message payload.
|
|
* @param {Buffer[]} inventory - Inventory vector list (encoded)
|
|
* @return {Buffer} Encoded payload.
|
|
*/
|
|
encodePayload: function(inventory) {
|
|
assert(inventory.length <= 50000, "Too many inventory entires");
|
|
var invBuf = Buffer.concat(inventory);
|
|
return Buffer.concat([structs.var_int.encode(inventory.length), invBuf]);
|
|
},
|
|
};
|
|
|
|
/**
|
|
* `getdata` message. `getdata` is used in response to an `inv` message
|
|
* to retrieve the content of a specific object after filtering known
|
|
* elements.
|
|
* @see {@link https://bitmessage.org/wiki/Protocol_specification#getdata}
|
|
* @namespace
|
|
*/
|
|
exports.getdata = objectAssign({}, inv, {
|
|
decode: function(buf) {
|
|
var decoded = message.decode(buf);
|
|
assert(decoded.command === "getdata", "Bad command");
|
|
return inv.decodePayload(decoded.payload);
|
|
},
|
|
encode: function(inventory) {
|
|
var payload = inv.encodePayload(inventory);
|
|
return message.encode("getdata", payload);
|
|
},
|
|
});
|
|
|
|
/**
|
|
* `error` message.
|
|
* @see {@link https://bitmessage.org/wiki/Protocol_specification_v3#error}
|
|
* @namespace
|
|
* @static
|
|
*/
|
|
var error = exports.error = {
|
|
/**
|
|
* Just a warning.
|
|
*/
|
|
WARNING: 0,
|
|
|
|
/**
|
|
* It's an error, something was going wrong (e.g. an object got lost).
|
|
*/
|
|
ERROR: 1,
|
|
|
|
/**
|
|
* It's a fatal error. The node will drop the line for that error and
|
|
* maybe ban you for some time.
|
|
*/
|
|
FATAL: 2,
|
|
|
|
/**
|
|
* Decode `error` message.
|
|
* @param {Buffer} buf - Message
|
|
* @return {Object} Decoded `error` structure.
|
|
*/
|
|
decode: function(buf) {
|
|
var decoded = message.decode(buf);
|
|
assert(decoded.command === "error", "Bad command");
|
|
return error.decodePayload(decoded.payload);
|
|
},
|
|
|
|
/**
|
|
* Decode `error` message payload.
|
|
* @param {Buffer} buf - Message payload
|
|
* @return {Object} Decoded `error` structure.
|
|
*/
|
|
decodePayload: function(buf) {
|
|
assert(buf.length >= 4, "Buffer is too small");
|
|
var decodedFatal = structs.var_int.decode(buf);
|
|
var decodedBanTime = structs.var_int.decode(decodedFatal.rest);
|
|
var decodedVector = structs.var_str.decode(decodedBanTime.rest);
|
|
var decodedErrorText = structs.var_str.decode(decodedVector.rest);
|
|
var length = (
|
|
decodedFatal.length +
|
|
decodedBanTime.length +
|
|
decodedVector.length +
|
|
decodedErrorText.length
|
|
);
|
|
return {
|
|
fatal: decodedFatal.value,
|
|
banTime: decodedBanTime.value,
|
|
vector: decodedVector.str,
|
|
errorText: decodedErrorText.str,
|
|
// Real data length.
|
|
length: length,
|
|
};
|
|
},
|
|
|
|
/**
|
|
* Encode `error` message.
|
|
* @param {Object} opts - Error options
|
|
* @return {Buffer} Encoded message.
|
|
*/
|
|
encode: function(opts) {
|
|
var payload = error.encodePayload(opts);
|
|
return message.encode("error", payload);
|
|
},
|
|
|
|
/**
|
|
* Encode `error` message payload.
|
|
* @param {Object} opts - Error options
|
|
* @return {Buffer} Encoded payload.
|
|
*/
|
|
encodePayload: function(opts) {
|
|
var fatal = opts.fatal || error.WARNING;
|
|
var banTime = opts.banTime || 0;
|
|
var vector = opts.vector || "";
|
|
var errorText = opts.errorText || "";
|
|
return Buffer.concat([
|
|
structs.var_int.encode(fatal),
|
|
structs.var_int.encode(banTime),
|
|
structs.var_str.encode(vector),
|
|
structs.var_str.encode(errorText),
|
|
]);
|
|
},
|
|
};
|