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

74 lines
1.9 KiB
JavaScript

// Copyright 2015 Joyent, Inc.
module.exports = {
read: read,
write: write
};
var assert = require('assert-plus');
var utils = require('../utils');
var Key = require('../key');
var PrivateKey = require('../private-key');
var pem = require('./pem');
var ssh = require('./ssh');
var rfc4253 = require('./rfc4253');
function read(buf, options) {
if (typeof (buf) === 'string') {
if (buf.trim().match(/^[-]+[ ]*BEGIN/))
return (pem.read(buf, options));
if (buf.match(/^\s*ssh-[a-z]/))
return (ssh.read(buf, options));
if (buf.match(/^\s*ecdsa-/))
return (ssh.read(buf, options));
buf = new Buffer(buf, 'binary');
} else {
assert.buffer(buf);
if (findPEMHeader(buf))
return (pem.read(buf, options));
if (findSSHHeader(buf))
return (ssh.read(buf, options));
}
if (buf.readUInt32BE(0) < buf.length)
return (rfc4253.read(buf, options));
throw (new Error('Failed to auto-detect format of key'));
}
function findSSHHeader(buf) {
var offset = 0;
while (offset < buf.length &&
(buf[offset] === 32 || buf[offset] === 10 || buf[offset] === 9))
++offset;
if (offset + 4 <= buf.length &&
buf.slice(offset, offset + 4).toString('ascii') === 'ssh-')
return (true);
if (offset + 6 <= buf.length &&
buf.slice(offset, offset + 6).toString('ascii') === 'ecdsa-')
return (true);
return (false);
}
function findPEMHeader(buf) {
var offset = 0;
while (offset < buf.length &&
(buf[offset] === 32 || buf[offset] === 10))
++offset;
if (buf[offset] !== 45)
return (false);
while (offset < buf.length &&
(buf[offset] === 45))
++offset;
while (offset < buf.length &&
(buf[offset] === 32))
++offset;
if (offset + 5 > buf.length ||
buf.slice(offset, offset + 5).toString('ascii') !== 'BEGIN')
return (false);
return (true);
}
function write(key, options) {
throw (new Error('"auto" format cannot be used for writing'));
}