bloodymary/node_modules/sshpk/lib/utils.js
2020-05-17 12:54:26 +00:00

288 lines
6.9 KiB
JavaScript

// Copyright 2015 Joyent, Inc.
module.exports = {
bufferSplit: bufferSplit,
addRSAMissing: addRSAMissing,
calculateDSAPublic: calculateDSAPublic,
mpNormalize: mpNormalize,
ecNormalize: ecNormalize,
countZeros: countZeros,
assertCompatible: assertCompatible,
isCompatible: isCompatible,
opensslKeyDeriv: opensslKeyDeriv,
opensshCipherInfo: opensshCipherInfo
};
var assert = require('assert-plus');
var PrivateKey = require('./private-key');
var crypto = require('crypto');
var MAX_CLASS_DEPTH = 3;
function isCompatible(obj, klass, needVer) {
if (obj === null || typeof (obj) !== 'object')
return (false);
if (needVer === undefined)
needVer = klass.prototype._sshpkApiVersion;
if (obj instanceof klass &&
klass.prototype._sshpkApiVersion[0] == needVer[0])
return (true);
var proto = Object.getPrototypeOf(obj);
var depth = 0;
while (proto.constructor.name !== klass.name) {
proto = Object.getPrototypeOf(proto);
if (!proto || ++depth > MAX_CLASS_DEPTH)
return (false);
}
if (proto.constructor.name !== klass.name)
return (false);
var ver = proto._sshpkApiVersion;
if (ver === undefined)
ver = klass._oldVersionDetect(obj);
if (ver[0] != needVer[0] || ver[1] < needVer[1])
return (false);
return (true);
}
function assertCompatible(obj, klass, needVer, name) {
if (name === undefined)
name = 'object';
assert.ok(obj, name + ' must not be null');
assert.object(obj, name + ' must be an object');
if (needVer === undefined)
needVer = klass.prototype._sshpkApiVersion;
if (obj instanceof klass &&
klass.prototype._sshpkApiVersion[0] == needVer[0])
return;
var proto = Object.getPrototypeOf(obj);
var depth = 0;
while (proto.constructor.name !== klass.name) {
proto = Object.getPrototypeOf(proto);
assert.ok(proto && ++depth <= MAX_CLASS_DEPTH,
name + ' must be a ' + klass.name + ' instance');
}
assert.strictEqual(proto.constructor.name, klass.name,
name + ' must be a ' + klass.name + ' instance');
var ver = proto._sshpkApiVersion;
if (ver === undefined)
ver = klass._oldVersionDetect(obj);
assert.ok(ver[0] == needVer[0] && ver[1] >= needVer[1],
name + ' must be compatible with ' + klass.name + ' klass ' +
'version ' + needVer[0] + '.' + needVer[1]);
}
var CIPHER_LEN = {
'des-ede3-cbc': { key: 7, iv: 8 },
'aes-128-cbc': { key: 16, iv: 16 }
};
var PKCS5_SALT_LEN = 8;
function opensslKeyDeriv(cipher, salt, passphrase, count) {
assert.buffer(salt, 'salt');
assert.buffer(passphrase, 'passphrase');
assert.number(count, 'iteration count');
var clen = CIPHER_LEN[cipher];
assert.object(clen, 'supported cipher');
salt = salt.slice(0, PKCS5_SALT_LEN);
var D, D_prev, bufs;
var material = new Buffer(0);
while (material.length < clen.key + clen.iv) {
bufs = [];
if (D_prev)
bufs.push(D_prev);
bufs.push(passphrase);
bufs.push(salt);
D = Buffer.concat(bufs);
for (var j = 0; j < count; ++j)
D = crypto.createHash('md5').update(D).digest();
material = Buffer.concat([material, D]);
D_prev = D;
}
return ({
key: material.slice(0, clen.key),
iv: material.slice(clen.key, clen.key + clen.iv)
});
}
/* Count leading zero bits on a buffer */
function countZeros(buf) {
var o = 0, obit = 8;
while (o < buf.length) {
var mask = (1 << obit);
if ((buf[o] & mask) === mask)
break;
obit--;
if (obit < 0) {
o++;
obit = 8;
}
}
return (o*8 + (8 - obit) - 1);
}
function bufferSplit(buf, chr) {
assert.buffer(buf);
assert.string(chr);
var parts = [];
var lastPart = 0;
var matches = 0;
for (var i = 0; i < buf.length; ++i) {
if (buf[i] === chr.charCodeAt(matches))
++matches;
else if (buf[i] === chr.charCodeAt(0))
matches = 1;
else
matches = 0;
if (matches >= chr.length) {
var newPart = i + 1;
parts.push(buf.slice(lastPart, newPart - matches));
lastPart = newPart;
matches = 0;
}
}
if (lastPart <= buf.length)
parts.push(buf.slice(lastPart, buf.length));
return (parts);
}
function ecNormalize(buf, addZero) {
assert.buffer(buf);
if (buf[0] === 0x00 && buf[1] === 0x04) {
if (addZero)
return (buf);
return (buf.slice(1));
} else if (buf[0] === 0x04) {
if (!addZero)
return (buf);
} else {
while (buf[0] === 0x00)
buf = buf.slice(1);
if (buf[0] === 0x02 || buf[0] === 0x03)
throw (new Error('Compressed elliptic curve points ' +
'are not supported'));
if (buf[0] !== 0x04)
throw (new Error('Not a valid elliptic curve point'));
if (!addZero)
return (buf);
}
var b = new Buffer(buf.length + 1);
b[0] = 0x0;
buf.copy(b, 1);
return (b);
}
function mpNormalize(buf) {
assert.buffer(buf);
while (buf.length > 1 && buf[0] === 0x00 && (buf[1] & 0x80) === 0x00)
buf = buf.slice(1);
if ((buf[0] & 0x80) === 0x80) {
var b = new Buffer(buf.length + 1);
b[0] = 0x00;
buf.copy(b, 1);
buf = b;
}
return (buf);
}
function bigintToMpBuf(bigint) {
var buf = new Buffer(bigint.toByteArray());
buf = mpNormalize(buf);
return (buf);
}
function calculateDSAPublic(g, p, x) {
assert.buffer(g);
assert.buffer(p);
assert.buffer(x);
try {
var bigInt = require('jsbn').BigInteger;
} catch (e) {
throw (new Error('To load a PKCS#8 format DSA private key, ' +
'the node jsbn library is required.'));
}
g = new bigInt(g);
p = new bigInt(p);
x = new bigInt(x);
var y = g.modPow(x, p);
var ybuf = bigintToMpBuf(y);
return (ybuf);
}
function addRSAMissing(key) {
assert.object(key);
assertCompatible(key, PrivateKey, [1, 1]);
try {
var bigInt = require('jsbn').BigInteger;
} catch (e) {
throw (new Error('To write a PEM private key from ' +
'this source, the node jsbn lib is required.'));
}
var d = new bigInt(key.part.d.data);
var buf;
if (!key.part.dmodp) {
var p = new bigInt(key.part.p.data);
var dmodp = d.mod(p.subtract(1));
buf = bigintToMpBuf(dmodp);
key.part.dmodp = {name: 'dmodp', data: buf};
key.parts.push(key.part.dmodp);
}
if (!key.part.dmodq) {
var q = new bigInt(key.part.q.data);
var dmodq = d.mod(q.subtract(1));
buf = bigintToMpBuf(dmodq);
key.part.dmodq = {name: 'dmodq', data: buf};
key.parts.push(key.part.dmodq);
}
}
function opensshCipherInfo(cipher) {
var inf = {};
switch (cipher) {
case '3des-cbc':
inf.keySize = 24;
inf.blockSize = 8;
inf.opensslName = 'des-ede3-cbc';
break;
case 'blowfish-cbc':
inf.keySize = 16;
inf.blockSize = 8;
inf.opensslName = 'bf-cbc';
break;
case 'aes128-cbc':
case 'aes128-ctr':
case 'aes128-gcm@openssh.com':
inf.keySize = 16;
inf.blockSize = 16;
inf.opensslName = 'aes-128-' + cipher.slice(7, 10);
break;
case 'aes192-cbc':
case 'aes192-ctr':
case 'aes192-gcm@openssh.com':
inf.keySize = 24;
inf.blockSize = 16;
inf.opensslName = 'aes-192-' + cipher.slice(7, 10);
break;
case 'aes256-cbc':
case 'aes256-ctr':
case 'aes256-gcm@openssh.com':
inf.keySize = 32;
inf.blockSize = 16;
inf.opensslName = 'aes-256-' + cipher.slice(7, 10);
break;
default:
throw (new Error(
'Unsupported openssl cipher "' + cipher + '"'));
}
return (inf);
}