<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="utf-8">
<title>JSDoc: Source: crypto/pkcs1.js</title>
<script src="scripts/prettify/prettify.js"> </script>
<script src="scripts/prettify/lang-css.js"> </script>
<!--[if lt IE 9]>
<script src="//html5shiv.googlecode.com/svn/trunk/html5.js"></script>
<![endif]-->
<link type="text/css" rel="stylesheet" href="styles/prettify-tomorrow.css">
<link type="text/css" rel="stylesheet" href="styles/jsdoc-default.css">
</head>
<body>
<div id="main">
<h1 class="page-title">Source: crypto/pkcs1.js</h1>
<section>
<article>
<pre class="prettyprint source"><code>// GPG4Browsers - An OpenPGP implementation in javascript
// Copyright (C) 2011 Recurity Labs GmbH
//
// This library is free software; you can redistribute it and/or
// modify it under the terms of the GNU Lesser General Public
// License as published by the Free Software Foundation; either
// version 2.1 of the License, or (at your option) any later version.
//
// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
// Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public
// License along with this library; if not, write to the Free Software
// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
/**
* PKCS1 encoding
* @requires crypto/crypto
* @requires crypto/hash
* @requires crypto/public_key/jsbn
* @requires crypto/random
* @requires util
* @module crypto/pkcs1
*/
/**
* ASN1 object identifiers for hashes (See {@link http://tools.ietf.org/html/rfc4880#section-5.2.2})
*/
hash_headers = [];
hash_headers[1] = [0x30, 0x20, 0x30, 0x0c, 0x06, 0x08, 0x2a, 0x86, 0x48, 0x86, 0xf7, 0x0d, 0x02, 0x05, 0x05, 0x00, 0x04,
0x10
];
hash_headers[2] = [0x30, 0x21, 0x30, 0x09, 0x06, 0x05, 0x2b, 0x0e, 0x03, 0x02, 0x1a, 0x05, 0x00, 0x04, 0x14];
hash_headers[3] = [0x30, 0x21, 0x30, 0x09, 0x06, 0x05, 0x2B, 0x24, 0x03, 0x02, 0x01, 0x05, 0x00, 0x04, 0x14];
hash_headers[8] = [0x30, 0x31, 0x30, 0x0d, 0x06, 0x09, 0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x01, 0x05, 0x00,
0x04, 0x20
];
hash_headers[9] = [0x30, 0x41, 0x30, 0x0d, 0x06, 0x09, 0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x02, 0x05, 0x00,
0x04, 0x30
];
hash_headers[10] = [0x30, 0x51, 0x30, 0x0d, 0x06, 0x09, 0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x03, 0x05,
0x00, 0x04, 0x40
];
hash_headers[11] = [0x30, 0x31, 0x30, 0x0d, 0x06, 0x09, 0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x04, 0x05,
0x00, 0x04, 0x1C
];
var crypto = require('./crypto.js'),
random = require('./random.js'),
util = require('../util.js'),
BigInteger = require('./public_key/jsbn.js'),
hash = require('./hash');
module.exports = {
eme: {
/**
* create a EME-PKCS1-v1_5 padding (See {@link http://tools.ietf.org/html/rfc4880#section-13.1.1|RFC 4880 13.1.1})
* @param {String} message message to be padded
* @param {Integer} length Length to the resulting message
* @return {String} EME-PKCS1 padded message
*/
encode: function(message, length) {
if (message.length > length - 11)
return -1;
var result = "";
result += String.fromCharCode(0);
result += String.fromCharCode(2);
for (var i = 0; i < length - message.length - 3; i++) {
result += String.fromCharCode(random.getPseudoRandom(1, 255));
}
result += String.fromCharCode(0);
result += message;
return result;
},
/**
* decodes a EME-PKCS1-v1_5 padding (See {@link http://tools.ietf.org/html/rfc4880#section-13.1.2|RFC 4880 13.1.2})
* @param {String} message EME-PKCS1 padded message
* @return {String} decoded message
*/
decode: function(message, len) {
if (message.length < len)
message = String.fromCharCode(0) + message;
if (message.length < 12 || message.charCodeAt(0) !== 0 || message.charCodeAt(1) != 2)
return -1;
var i = 2;
while (message.charCodeAt(i) !== 0 && message.length > i)
i++;
return message.substring(i + 1, message.length);
}
},
emsa: {
/**
* create a EMSA-PKCS1-v1_5 padding (See {@link http://tools.ietf.org/html/rfc4880#section-13.1.3|RFC 4880 13.1.3})
* @param {Integer} algo Hash algorithm type used
* @param {String} data Data to be hashed
* @param {Integer} keylength Key size of the public mpi in bytes
* @returns {String} Hashcode with pkcs1padding as string
*/
encode: function(algo, data, keylength) {
var data2 = "";
data2 += String.fromCharCode(0x00);
data2 += String.fromCharCode(0x01);
var i;
for (i = 0; i < (keylength - hash_headers[algo].length - 3 -
hash.getHashByteLength(algo)); i++)
data2 += String.fromCharCode(0xff);
data2 += String.fromCharCode(0x00);
for (i = 0; i < hash_headers[algo].length; i++)
data2 += String.fromCharCode(hash_headers[algo][i]);
data2 += hash.digest(algo, data);
return new BigInteger(util.hexstrdump(data2), 16);
},
/**
* extract the hash out of an EMSA-PKCS1-v1.5 padding (See {@link http://tools.ietf.org/html/rfc4880#section-13.1.3|RFC 4880 13.1.3})
* @param {String} data Hash in pkcs1 encoding
* @returns {String} The hash as string
*/
decode: function(algo, data) {
var i = 0;
if (data.charCodeAt(0) === 0) i++;
else if (data.charCodeAt(0) != 1) return -1;
else i++;
while (data.charCodeAt(i) == 0xFF) i++;
if (data.charCodeAt(i++) !== 0) return -1;
var j = 0;
for (j = 0; j < hash_headers[algo].length && j + i < data.length; j++) {
if (data.charCodeAt(j + i) != hash_headers[algo][j]) return -1;
}
i += j;
if (data.substring(i).length < hash.getHashByteLength(algo)) return -1;
return data.substring(i);
}
}
};
</code></pre>
</article>
</section>
</div>
<nav>
<h2><a href="index.html">Index</a></h2><h3>Modules</h3><ul><li><a href="module-async_proxy.html">async_proxy</a></li><li><a href="module-cleartext.html">cleartext</a></li><li><a href="module-config.html">config</a></li><li><a href="config.html">config/config</a></li><li><a href="localStorage.html">config/localStorage</a></li><li><a href="module-crypto.html">crypto</a></li><li><a href="cfb.html">crypto/cfb</a></li><li><a href="cipher.html">crypto/cipher</a></li><li><a href="aes.html">crypto/cipher/aes</a></li><li><a href="blowfish.html">crypto/cipher/blowfish</a></li><li><a href="cast5.html">crypto/cipher/cast5</a></li><li><a href="des.html">crypto/cipher/des</a></li><li><a href="twofish.html">crypto/cipher/twofish</a></li><li><a href="crypto.html">crypto/crypto</a></li><li><a href="hash.html">crypto/hash</a></li><li><a href="md5.html">crypto/hash/md5</a></li><li><a href="ripe-md.html">crypto/hash/ripe-md</a></li><li><a href="sha.html">crypto/hash/sha</a></li><li><a href="pkcs1.html">crypto/pkcs1</a></li><li><a href="public_key.html">crypto/public_key</a></li><li><a href="dsa.html">crypto/public_key/dsa</a></li><li><a href="elgamal.html">crypto/public_key/elgamal</a></li><li><a href="jsbn.html">crypto/public_key/jsbn</a></li><li><a href="rsa.html">crypto/public_key/rsa</a></li><li><a href="random.html">crypto/random</a></li><li><a href="signature.html">crypto/signature</a></li><li><a href="armor.html">encoding/armor</a></li><li><a href="base64.html">encoding/base64</a></li><li><a href="module-enums.html">enums</a></li><li><a href="module-key.html">key</a></li><li><a href="module-keyring.html">keyring</a></li><li><a href="keyring.html">keyring/keyring</a></li><li><a href="localstore.html">keyring/localstore</a></li><li><a href="module-message.html">message</a></li><li><a href="module-openpgp.html">openpgp</a></li><li><a href="module-packet.html">packet</a></li><li><a href="compressed.html">packet/compressed</a></li><li><a href="literal.html">packet/literal</a></li><li><a href="marker.html">packet/marker</a></li><li><a href="one_pass_signature.html">packet/one_pass_signature</a></li><li><a href="packet.html">packet/packet</a></li><li><a href="packetlist.html">packet/packetlist</a></li><li><a href="public_key_.html">packet/public_key</a></li><li><a href="public_key_encrypted_session_key.html">packet/public_key_encrypted_session_key</a></li><li><a href="public_subkey.html">packet/public_subkey</a></li><li><a href="secret_key.html">packet/secret_key</a></li><li><a href="secret_subkey.html">packet/secret_subkey</a></li><li><a href="signature_.html">packet/signature</a></li><li><a href="sym_encrypted_integrity_protected.html">packet/sym_encrypted_integrity_protected</a></li><li><a href="sym_encrypted_session_key.html">packet/sym_encrypted_session_key</a></li><li><a href="symmetrically_encrypted.html">packet/symmetrically_encrypted</a></li><li><a href="trust.html">packet/trust</a></li><li><a href="user_attribute.html">packet/user_attribute</a></li><li><a href="userid.html">packet/userid</a></li><li><a href="keyid.html">type/keyid</a></li><li><a href="mpi.html">type/mpi</a></li><li><a href="s2k.html">type/s2k</a></li><li><a href="module-util.html">util</a></li></ul><h3>Classes</h3><ul><li><a href="JXG.Util.html">JXG.Util</a></li><li><a href="module-async_proxy-AsyncProxy.html">async_proxy~AsyncProxy</a></li><li><a href="module-cleartext-CleartextMessage.html">cleartext~CleartextMessage</a></li><li><a href="localStorage-LocalStorage.html">config/localStorage~LocalStorage</a></li><li><a href="keyring-Keyring.html">keyring/keyring~Keyring</a></li><li><a href="module-key-Key.html">key~Key</a></li><li><a href="module-key-SubKey.html">key~SubKey</a></li><li><a href="module-key-User.html">key~User</a></li><li><a href="module-message-Message.html">message~Message</a></li><li><a href="compressed-Compressed.html">packet/compressed~Compressed</a></li><li><a href="literal-Literal.html">packet/literal~Literal</a></li><li><a href="marker-Marker.html">packet/marker~Marker</a></li><li><a href="one_pass_signature-OnePassSignature.html">packet/one_pass_signature~OnePassSignature</a></li><li><a href="packetlist-Packetlist.html">packet/packetlist~Packetlist</a></li><li><a href="public_key_encrypted_session_key-PublicKeyEncryptedSessionKey.html">packet/public_key_encrypted_session_key~PublicKeyEncryptedSessionKey</a></li><li><a href="public_key-PublicKey.html">packet/public_key~PublicKey</a></li><li><a href="public_subkey-PublicSubkey.html">packet/public_subkey~PublicSubkey</a></li><li><a href="secret_key-SecretKey.html">packet/secret_key~SecretKey</a></li><li><a href="secret_subkey-SecretSubkey.html">packet/secret_subkey~SecretSubkey</a></li><li><a href="signature-Signature.html">packet/signature~Signature</a></li><li><a href="sym_encrypted_integrity_protected-SymEncryptedIntegrityProtected.html">packet/sym_encrypted_integrity_protected~SymEncryptedIntegrityProtected</a></li><li><a href="sym_encrypted_session_key-SymEncryptedSessionKey.html">packet/sym_encrypted_session_key~SymEncryptedSessionKey</a></li><li><a href="symmetrically_encrypted-SymmetricallyEncrypted.html">packet/symmetrically_encrypted~SymmetricallyEncrypted</a></li><li><a href="trust-Trust.html">packet/trust~Trust</a></li><li><a href="user_attribute-UserAttribute.html">packet/user_attribute~UserAttribute</a></li><li><a href="userid-Userid.html">packet/userid~Userid</a></li><li><a href="keyid-Keyid.html">type/keyid~Keyid</a></li><li><a href="mpi-MPI.html">type/mpi~MPI</a></li><li><a href="s2k-S2K.html">type/s2k~S2K</a></li></ul>
</nav>
<br clear="both">
<footer>
Documentation generated by <a href="https://github.com/jsdoc3/jsdoc">JSDoc 3.2.2</a> on Wed Feb 12 2014 15:09:01 GMT+0100 (MEZ)
</footer>
<script> prettyPrint(); </script>
<script src="scripts/linenumber.js"> </script>
</body>
</html>