/**
* Working with Bitmessage addresses.
* **NOTE**: `Address` is exported as a module.
* @example
* var Address = require("bitmessage").Address;
*
* // Generate a new random Bitmessage identity.
* var addr1 = Address.fromRandom();
* console.log("New random Bitmessage address:", addr1.encode());
*
* // Or create it from passphrase.
* var addr2 = Address.fromPassphrase("test");
* console.log("Deterministic Bitmessage address:", addr2.encode());
* @see {@link https://bitmessage.org/wiki/Address}
* @module bitmessage/address
*/
// TODO(Kagami): Document getters/setters.
"use strict";
var objectAssign = Object.assign || require("object-assign");
var bufferEqual = require("buffer-equal");
var bs58 = require("bs58");
var assert = require("./_util").assert;
var var_int = require("./structs").var_int;
var PubkeyBitfield = require("./structs").PubkeyBitfield;
var bmcrypto = require("./crypto");
var popkey = require("./_util").popkey;
/**
* Create a new Bitmessage address object.
* @param {Object=} opts - Address options
* @param {number} opts.version - Version number (4 by default)
* @param {number} opts.stream - Stream number (1 by default)
* @param {Object} opts.behavior - [Pubkey features]{@link
* module:bitmessage/structs.PubkeyBitfield} (`DOES_ACK` by default)
* @param {Buffer} opts.signPrivateKey - Signing private key
* @param {Buffer} opts.signPublicKey - Signing public key
* @param {Buffer} opts.encPrivateKey - Encryption private key
* @param {Buffer} opts.encPublicKey - Encryption public key
* @param {Buffer} opts.ripe - Keys RIPEMD hash
* @constructor
* @static
*/
function Address(opts) {
if (!(this instanceof Address)) {
return new Address(opts);
}
opts = objectAssign({}, opts);
// Pull out version right away because it may be needed in setters.
this.version = popkey(opts, "version") || 4;
assert(this.version <= 4, "Version too high");
assert(this.version >= 1, "Version too low");
// Set defaults.
opts.stream = opts.stream || 1;
opts.behavior = opts.behavior ||
PubkeyBitfield().set(PubkeyBitfield.DOES_ACK);
// Merge remained values.
objectAssign(this, opts);
}
/**
* Create a copy of the address object.
* @return {Address} Cloned address.
*/
Address.prototype.clone = function() {
return new Address(this);
};
/**
* Test if the given object is an Address instance.
* NOTE: Implementation is just simple `instanceof` but it improves
* readability and consistent with `isArray`, `isBuffer`, etc.
* @param {Object} obj - Given object
* @return {boolean}
*/
Address.isAddress = function(obj) {
return obj instanceof Address;
};
/**
* Parse Bitmessage address into address object.
* @param {string} str - Address string (with or without `BM-` prefix)
* @return {Address} Decoded address object.
*/
Address.decode = function(str) {
if (Address.isAddress(str)) {
return str;
}
str = str.trim();
if (str.slice(0, 3) === "BM-") {
str = str.slice(3);
}
var bytes = bs58.decode(str);
var data = new Buffer(bytes.slice(0, -4));
var checksum = new Buffer(bytes.slice(-4));
assert(bufferEqual(checksum, getaddrchecksum(data)), "Bad checkum");
var decoded = var_int.decode(data);
var version = decoded.value;
data = decoded.rest;
decoded = var_int.decode(data);
var stream = decoded.value;
var ripe = decoded.rest;
if (version === 4) {
assert(ripe[0] !== 0, "Ripe encode error");
}
return new Address({version: version, stream: stream, ripe: ripe});
};
// Compute the Bitmessage checksum for the given data.
function getaddrchecksum(data) {
return bmcrypto.sha512(bmcrypto.sha512(data)).slice(0, 4);
}
/**
* Get the RIPEMD hash of the address keys without prefix nulls.
* @return {Buffer} A short RIPEMD hash.
*/
Address.prototype.getShortRipe = function() {
var ripe = this.ripe;
return ripe.slice(20 - getripelen(ripe));
};
function getaddrhash(addr) {
var dataToHash = Buffer.concat([
var_int.encode(addr.version),
var_int.encode(addr.stream),
addr.ripe,
]);
return bmcrypto.sha512(dataToHash);
}
/**
* Calculate the encryption key used to encrypt/decrypt
* [pubkey]{@link module:bitmessage/objects.pubkey} objects.
* @return {Buffer} A 32-byte private key.
*/
Address.prototype.getPubkeyPrivateKey = function() {
return bmcrypto.sha512(getaddrhash(this)).slice(0, 32);
};
/**
* Calculate the corresponding public key for encryption key used to
* encrypt/decrypt
* [pubkey]{@link module:bitmessage/objects.pubkey} objects.
* @return {Buffer} A 65-byte public key.
*/
Address.prototype.getPubkeyPublicKey = function() {
return bmcrypto.getPublic(this.getPubkeyPrivateKey());
};
/**
* Calculate the encryption key used to encrypt/decrypt
* [broadcast]{@link module:bitmessage/objects.broadcast} objects.
* @return {Buffer} A 32-byte private key.
*/
Address.prototype.getBroadcastPrivateKey = function() {
if (this.version >= 4) {
return bmcrypto.sha512(getaddrhash(this)).slice(0, 32);
} else {
return getaddrhash(this).slice(0, 32);
}
};
/**
* Calculate the corresponding public key for encryption key used to
* encrypt/decrypt
* [broadcast]{@link module:bitmessage/objects.broadcast} objects.
* @return {Buffer} A 65-byte public key.
*/
Address.prototype.getBroadcastPublicKey = function() {
return bmcrypto.getPublic(this.getBroadcastPrivateKey());
};
/**
* Calculate the address tag.
* @return {Buffer} A 32-byte address tag.
*/
Address.prototype.getTag = function() {
return bmcrypto.sha512(getaddrhash(this)).slice(32);
};
// Get truncated ripe hash length.
function getripelen(ripe) {
var zeroes = 0;
for (var i = 0; i < 20, ripe[i] === 0; i++) {
zeroes++;
}
return 20 - zeroes;
}
// Do neccessary checkings of the truncated ripe hash length depending
// on the address version.
function assertripelen(ripelen, version, ripe) {
if (ripe) {
assert(ripe.length <= 20, "Bad ripe");
}
switch (version) {
case 1:
assert(ripelen === 20, "Bad ripe length");
break;
case 2:
case 3:
assert(ripelen >= 18, "Ripe is too short");
assert(ripelen <= 20, "Ripe is too long");
break;
case 4:
assert(ripelen >= 4, "Ripe is too short");
assert(ripelen <= 20, "Ripe is too long");
break;
default:
throw new Error("Bad version");
}
}
// The same as `assertripelen` but return boolean instead of thrown an
// Error.
function checkripelen(ripelen, version) {
try {
assertripelen(ripelen, version);
return true;
} catch(e) {
return false;
}
}
/**
* Encode Bitmessage address object into address string.
* @return {string} Address string.
*/
Address.prototype.encode = function() {
var data = Buffer.concat([
var_int.encode(this.version),
var_int.encode(this.stream),
this.getShortRipe(),
]);
var addr = Buffer.concat([data, getaddrchecksum(data)]);
return "BM-" + bs58.encode(addr);
};
/**
* Create a new Bitmessage address with random encryption and signing
* private keys.
* @param {Object=} opts - Address options
* @param {number} opts.ripeLength - Required length of the short RIPEMD
* hash (19 by default)
* @param {number} opts.version - Version number (4 by default)
* @param {number} opts.stream - Stream number (1 by default)
* @param {Object} opts.behavior - [Pubkey features]{@link module:bitmessage/structs.PubkeyBitfield} (`DOES_ACK` by default)
* @return {Address} New address object.
*/
Address.fromRandom = function(opts) {
opts = objectAssign({}, opts);
var version = opts.version = opts.version || 4;
var ripelen = popkey(opts, "ripeLength") || 19;
assertripelen(ripelen, version);
// TODO(Kagami): Speed it up using web workers in Browser.
// TODO(Kagami): Bind to C++ version of this code in Node.
var encPrivateKey, encPublicKey, ripe, len;
var signPrivateKey = bmcrypto.getPrivate();
var signPublicKey = bmcrypto.getPublic(signPrivateKey);
var keysbuf = new Buffer(130);
signPublicKey.copy(keysbuf);
while (true) {
encPrivateKey = bmcrypto.getPrivate();
encPublicKey = bmcrypto.getPublic(encPrivateKey);
encPublicKey.copy(keysbuf, 65);
ripe = bmcrypto.ripemd160(bmcrypto.sha512(keysbuf));
len = getripelen(ripe);
if (len <= ripelen && checkripelen(len, version)) {
opts.signPrivateKey = signPrivateKey;
opts.encPrivateKey = encPrivateKey;
return new Address(opts);
}
}
};
/**
* Create a new Bitmessage address from passphrase.
* @param {(string|Object)} opts - Passphrase or address options
* @param {string} opts.passphrase - Passphrase to generate address from
* @param {number=} opts.ripeLength - Required length of the short
* RIPEMD hash (19 by default)
* @param {number=} opts.version - Version number (4 by default)
* @param {number=} opts.stream - Stream number (1 by default)
* @param {Object=} opts.behavior - [Pubkey features]{@link module:bitmessage/structs.PubkeyBitfield} (`DOES_ACK` by default)
* @return {Address} New address object.
*/
Address.fromPassphrase = function(opts) {
if (typeof opts === "string") {
opts = {passphrase: opts};
} else {
opts = objectAssign({}, opts);
}
var version = opts.version = opts.version || 4;
var ripelen = popkey(opts, "ripeLength") || 19;
assertripelen(ripelen, version);
var passphrase = popkey(opts, "passphrase");
// TODO(Kagami): Speed it up using web workers in Browser.
// TODO(Kagami): Bind to C++ version of this code in Node.
var signPrivateKey, signPublicKey, encPrivateKey, encPublicKey;
var ripe, len, tmp;
var signnonce = 0;
var encnonce = 1;
var keysbuf = new Buffer(130);
// XXX(Kagami): Spec doesn't mention encoding, using UTF-8.
var phrasebuf = new Buffer(passphrase, "utf8");
while (true) {
// TODO(Kagami): We may slightly optimize it and pre-create tmp
// buffers based on the encoded nonce size (1, 3, 5 and 9 bytes).
tmp = Buffer.concat([phrasebuf, var_int.encode(signnonce)]);
signPrivateKey = bmcrypto.sha512(tmp).slice(0, 32);
signPublicKey = bmcrypto.getPublic(signPrivateKey);
signPublicKey.copy(keysbuf);
tmp = Buffer.concat([phrasebuf, var_int.encode(encnonce)]);
encPrivateKey = bmcrypto.sha512(tmp).slice(0, 32);
encPublicKey = bmcrypto.getPublic(encPrivateKey);
encPublicKey.copy(keysbuf, 65);
ripe = bmcrypto.ripemd160(bmcrypto.sha512(keysbuf));
len = getripelen(ripe);
if (len <= ripelen && checkripelen(len, version)) {
opts.signPrivateKey = signPrivateKey;
opts.encPrivateKey = encPrivateKey;
return new Address(opts);
}
signnonce += 2;
encnonce += 2;
}
};
Object.defineProperty(Address.prototype, "signPrivateKey", {
get: function() {
return this._signPrivateKey;
},
set: function(signPrivateKey) {
this._signPrivateKey = signPrivateKey;
// Invalidate cached values;
delete this._signPublicKey;
delete this._ripe;
},
});
Object.defineProperty(Address.prototype, "signPublicKey", {
get: function() {
if (this._signPublicKey) {
return this._signPublicKey;
} else if (this.signPrivateKey) {
this._signPublicKey = bmcrypto.getPublic(this.signPrivateKey);
return this._signPublicKey;
} else {
throw new Error("No signing key");
}
},
set: function(signPublicKey) {
this._signPublicKey = signPublicKey;
},
});
Object.defineProperty(Address.prototype, "encPrivateKey", {
get: function() {
return this._encPrivateKey;
},
set: function(encPrivateKey) {
this._encPrivateKey = encPrivateKey;
// Invalidate cached values;
delete this._encPublicKey;
delete this._ripe;
},
});
Object.defineProperty(Address.prototype, "encPublicKey", {
get: function() {
if (this._encPublicKey) {
return this._encPublicKey;
} else if (this.encPrivateKey) {
this._encPublicKey = bmcrypto.getPublic(this.encPrivateKey);
return this._encPublicKey;
} else {
throw new Error("No encryption key");
}
},
set: function(encPublicKey) {
this._encPublicKey = encPublicKey;
},
});
Object.defineProperty(Address.prototype, "ripe", {
get: function() {
if (this._ripe) {
return this._ripe;
}
var dataToHash = Buffer.concat([this.signPublicKey, this.encPublicKey]);
this._ripe = bmcrypto.ripemd160(bmcrypto.sha512(dataToHash));
return this._ripe;
},
set: function(ripe) {
assertripelen(getripelen(ripe), this.version, ripe);
if (ripe.length < 20) {
var fullripe = new Buffer(20);
fullripe.fill(0);
ripe.copy(fullripe, 20 - ripe.length);
ripe = fullripe;
}
this._ripe = ripe;
},
});
module.exports = Address;