144 lines
3.8 KiB
JavaScript
144 lines
3.8 KiB
JavaScript
// much of this based on https://github.com/indutny/self-signed/blob/gh-pages/lib/rsa.js
|
|
var Buffer = require('safe-buffer').Buffer
|
|
var createHmac = require('create-hmac')
|
|
var crt = require('browserify-rsa')
|
|
var EC = require('elliptic').ec
|
|
var BN = require('bn.js')
|
|
var parseKeys = require('parse-asn1')
|
|
var curves = require('./curves.json')
|
|
|
|
function sign (hash, key, hashType, signType, tag) {
|
|
var priv = parseKeys(key)
|
|
if (priv.curve) {
|
|
// rsa keys can be interpreted as ecdsa ones in openssl
|
|
if (signType !== 'ecdsa' && signType !== 'ecdsa/rsa') throw new Error('wrong private key type')
|
|
return ecSign(hash, priv)
|
|
} else if (priv.type === 'dsa') {
|
|
if (signType !== 'dsa') throw new Error('wrong private key type')
|
|
return dsaSign(hash, priv, hashType)
|
|
} else {
|
|
if (signType !== 'rsa' && signType !== 'ecdsa/rsa') throw new Error('wrong private key type')
|
|
}
|
|
hash = Buffer.concat([tag, hash])
|
|
var len = priv.modulus.byteLength()
|
|
var pad = [0, 1]
|
|
while (hash.length + pad.length + 1 < len) pad.push(0xff)
|
|
pad.push(0x00)
|
|
var i = -1
|
|
while (++i < hash.length) pad.push(hash[i])
|
|
|
|
var out = crt(pad, priv)
|
|
return out
|
|
}
|
|
|
|
function ecSign (hash, priv) {
|
|
var curveId = curves[priv.curve.join('.')]
|
|
if (!curveId) throw new Error('unknown curve ' + priv.curve.join('.'))
|
|
|
|
var curve = new EC(curveId)
|
|
var key = curve.keyFromPrivate(priv.privateKey)
|
|
var out = key.sign(hash)
|
|
|
|
return Buffer.from(out.toDER())
|
|
}
|
|
|
|
function dsaSign (hash, priv, algo) {
|
|
var x = priv.params.priv_key
|
|
var p = priv.params.p
|
|
var q = priv.params.q
|
|
var g = priv.params.g
|
|
var r = new BN(0)
|
|
var k
|
|
var H = bits2int(hash, q).mod(q)
|
|
var s = false
|
|
var kv = getKey(x, q, hash, algo)
|
|
while (s === false) {
|
|
k = makeKey(q, kv, algo)
|
|
r = makeR(g, k, p, q)
|
|
s = k.invm(q).imul(H.add(x.mul(r))).mod(q)
|
|
if (s.cmpn(0) === 0) {
|
|
s = false
|
|
r = new BN(0)
|
|
}
|
|
}
|
|
return toDER(r, s)
|
|
}
|
|
|
|
function toDER (r, s) {
|
|
r = r.toArray()
|
|
s = s.toArray()
|
|
|
|
// Pad values
|
|
if (r[0] & 0x80) r = [0].concat(r)
|
|
if (s[0] & 0x80) s = [0].concat(s)
|
|
|
|
var total = r.length + s.length + 4
|
|
var res = [0x30, total, 0x02, r.length]
|
|
res = res.concat(r, [0x02, s.length], s)
|
|
return Buffer.from(res)
|
|
}
|
|
|
|
function getKey (x, q, hash, algo) {
|
|
x = Buffer.from(x.toArray())
|
|
if (x.length < q.byteLength()) {
|
|
var zeros = Buffer.alloc(q.byteLength() - x.length)
|
|
x = Buffer.concat([zeros, x])
|
|
}
|
|
var hlen = hash.length
|
|
var hbits = bits2octets(hash, q)
|
|
var v = Buffer.alloc(hlen)
|
|
v.fill(1)
|
|
var k = Buffer.alloc(hlen)
|
|
k = createHmac(algo, k).update(v).update(Buffer.from([0])).update(x).update(hbits).digest()
|
|
v = createHmac(algo, k).update(v).digest()
|
|
k = createHmac(algo, k).update(v).update(Buffer.from([1])).update(x).update(hbits).digest()
|
|
v = createHmac(algo, k).update(v).digest()
|
|
return { k: k, v: v }
|
|
}
|
|
|
|
function bits2int (obits, q) {
|
|
var bits = new BN(obits)
|
|
var shift = (obits.length << 3) - q.bitLength()
|
|
if (shift > 0) bits.ishrn(shift)
|
|
return bits
|
|
}
|
|
|
|
function bits2octets (bits, q) {
|
|
bits = bits2int(bits, q)
|
|
bits = bits.mod(q)
|
|
var out = Buffer.from(bits.toArray())
|
|
if (out.length < q.byteLength()) {
|
|
var zeros = Buffer.alloc(q.byteLength() - out.length)
|
|
out = Buffer.concat([zeros, out])
|
|
}
|
|
return out
|
|
}
|
|
|
|
function makeKey (q, kv, algo) {
|
|
var t
|
|
var k
|
|
|
|
do {
|
|
t = Buffer.alloc(0)
|
|
|
|
while (t.length * 8 < q.bitLength()) {
|
|
kv.v = createHmac(algo, kv.k).update(kv.v).digest()
|
|
t = Buffer.concat([t, kv.v])
|
|
}
|
|
|
|
k = bits2int(t, q)
|
|
kv.k = createHmac(algo, kv.k).update(kv.v).update(Buffer.from([0])).digest()
|
|
kv.v = createHmac(algo, kv.k).update(kv.v).digest()
|
|
} while (k.cmp(q) !== -1)
|
|
|
|
return k
|
|
}
|
|
|
|
function makeR (g, k, p, q) {
|
|
return g.toRed(BN.mont(p)).redPow(k).fromRed().mod(q)
|
|
}
|
|
|
|
module.exports = sign
|
|
module.exports.getKey = getKey
|
|
module.exports.makeKey = makeKey
|