Pusher REST JS SDK

by Ryan Duffy

JavaScript

/*
 *  jssha256 version 0.1  -  Copyright 2006 B. Poettering
 *
 *  This program is free software; you can redistribute it and/or
 *  modify it under the terms of the GNU General Public License as
 *  published by the Free Software Foundation; either version 2 of the
 *  License, or (at your option) any later version.
 *
 *  This program 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
 *  General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
 *  02111-1307 USA
 */

/*
 * http://point-at-infinity.org/jssha256/
 *
 * This is a JavaScript implementation of the SHA256 secure hash function
 * and the HMAC-SHA256 message authentication code (MAC).
 *
 * The routines' well-functioning has been verified with the test vectors 
 * given in FIPS-180-2, Appendix B and IETF RFC 4231. The HMAC algorithm 
 * conforms to IETF RFC 2104. 
 *
 * The following code example computes the hash value of the string "abc".
 *
 *    SHA256_init();
 *    SHA256_write("abc");
 *    digest = SHA256_finalize();  
 *    digest_hex = array_to_hex_string(digest);
 * 
 * Get the same result by calling the shortcut function SHA256_hash:
 * 
 *    digest_hex = SHA256_hash("abc");
 * 
 * In the following example the calculation of the HMAC of the string "abc" 
 * using the key "secret key" is shown:
 * 
 *    HMAC_SHA256_init("secret key");
 *    HMAC_SHA256_write("abc");
 *    mac = HMAC_SHA256_finalize();
 *    mac_hex = array_to_hex_string(mac);
 *
 * Again, the same can be done more conveniently:
 * 
 *    mac_hex = HMAC_SHA256_MAC("secret key", "abc");
 *
 * Note that the internal state of the hash function is held in global
 * variables. Therefore one hash value calculation...