documentit/node_modules/sshpk/lib/formats/pem.js
2018-01-05 10:48:13 -08:00

187 lines
4.7 KiB
JavaScript

// Copyright 2015 Joyent, Inc.
module.exports = {
read: read,
write: write
};
var assert = require('assert-plus');
var asn1 = require('asn1');
var crypto = require('crypto');
var algs = require('../algs');
var utils = require('../utils');
var Key = require('../key');
var PrivateKey = require('../private-key');
var pkcs1 = require('./pkcs1');
var pkcs8 = require('./pkcs8');
var sshpriv = require('./ssh-private');
var rfc4253 = require('./rfc4253');
var errors = require('../errors');
/*
* For reading we support both PKCS#1 and PKCS#8. If we find a private key,
* we just take the public component of it and use that.
*/
function read(buf, options, forceType) {
var input = buf;
if (typeof (buf) !== 'string') {
assert.buffer(buf, 'buf');
buf = buf.toString('ascii');
}
var lines = buf.trim().split('\n');
var m = lines[0].match(/*JSSTYLED*/
/[-]+[ ]*BEGIN ([A-Z0-9]+ )?(PUBLIC|PRIVATE) KEY[ ]*[-]+/);
assert.ok(m, 'invalid PEM header');
var m2 = lines[lines.length - 1].match(/*JSSTYLED*/
/[-]+[ ]*END ([A-Z0-9]+ )?(PUBLIC|PRIVATE) KEY[ ]*[-]+/);
assert.ok(m2, 'invalid PEM footer');
/* Begin and end banners must match key type */
assert.equal(m[2], m2[2]);
var type = m[2].toLowerCase();
var alg;
if (m[1]) {
/* They also must match algorithms, if given */
assert.equal(m[1], m2[1], 'PEM header and footer mismatch');
alg = m[1].trim();
}
var headers = {};
while (true) {
lines = lines.slice(1);
m = lines[0].match(/*JSSTYLED*/
/^([A-Za-z0-9-]+): (.+)$/);
if (!m)
break;
headers[m[1].toLowerCase()] = m[2];
}
var cipher, key, iv;
if (headers['proc-type']) {
var parts = headers['proc-type'].split(',');
if (parts[0] === '4' && parts[1] === 'ENCRYPTED') {
if (typeof (options.passphrase) === 'string') {
options.passphrase = new Buffer(
options.passphrase, 'utf-8');
}
if (!Buffer.isBuffer(options.passphrase)) {
throw (new errors.KeyEncryptedError(
options.filename, 'PEM'));
} else {
parts = headers['dek-info'].split(',');
assert.ok(parts.length === 2);
cipher = parts[0].toLowerCase();
iv = new Buffer(parts[1], 'hex');
key = utils.opensslKeyDeriv(cipher, iv,
options.passphrase, 1).key;
}
}
}
/* Chop off the first and last lines */
lines = lines.slice(0, -1).join('');
buf = new Buffer(lines, 'base64');
if (cipher && key && iv) {
var cipherStream = crypto.createDecipheriv(cipher, key, iv);
var chunk, chunks = [];
cipherStream.once('error', function (e) {
if (e.toString().indexOf('bad decrypt') !== -1) {
throw (new Error('Incorrect passphrase ' +
'supplied, could not decrypt key'));
}
throw (e);
});
cipherStream.write(buf);
cipherStream.end();
while ((chunk = cipherStream.read()) !== null)
chunks.push(chunk);
buf = Buffer.concat(chunks);
}
/* The new OpenSSH internal format abuses PEM headers */
if (alg && alg.toLowerCase() === 'openssh')
return (sshpriv.readSSHPrivate(type, buf, options));
if (alg && alg.toLowerCase() === 'ssh2')
return (rfc4253.readType(type, buf, options));
var der = new asn1.BerReader(buf);
der.originalInput = input;
/*
* All of the PEM file types start with a sequence tag, so chop it
* off here
*/
der.readSequence();
/* PKCS#1 type keys name an algorithm in the banner explicitly */
if (alg) {
if (forceType)
assert.strictEqual(forceType, 'pkcs1');
return (pkcs1.readPkcs1(alg, type, der));
} else {
if (forceType)
assert.strictEqual(forceType, 'pkcs8');
return (pkcs8.readPkcs8(alg, type, der));
}
}
function write(key, options, type) {
assert.object(key);
var alg = {'ecdsa': 'EC', 'rsa': 'RSA', 'dsa': 'DSA'}[key.type];
var header;
var der = new asn1.BerWriter();
if (PrivateKey.isPrivateKey(key)) {
if (type && type === 'pkcs8') {
header = 'PRIVATE KEY';
pkcs8.writePkcs8(der, key);
} else {
if (type)
assert.strictEqual(type, 'pkcs1');
header = alg + ' PRIVATE KEY';
pkcs1.writePkcs1(der, key);
}
} else if (Key.isKey(key)) {
if (type && type === 'pkcs1') {
header = alg + ' PUBLIC KEY';
pkcs1.writePkcs1(der, key);
} else {
if (type)
assert.strictEqual(type, 'pkcs8');
header = 'PUBLIC KEY';
pkcs8.writePkcs8(der, key);
}
} else {
throw (new Error('key is not a Key or PrivateKey'));
}
var tmp = der.buffer.toString('base64');
var len = tmp.length + (tmp.length / 64) +
18 + 16 + header.length*2 + 10;
var buf = new Buffer(len);
var o = 0;
o += buf.write('-----BEGIN ' + header + '-----\n', o);
for (var i = 0; i < tmp.length; ) {
var limit = i + 64;
if (limit > tmp.length)
limit = tmp.length;
o += buf.write(tmp.slice(i, limit), o);
buf[o++] = 10;
i = limit;
}
o += buf.write('-----END ' + header + '-----\n', o);
return (buf.slice(0, o));
}