source: Dev/trunk/src/client/dojox/encoding/digests/SHA512.js

define(["./_sha-64"], function(sha64){
        //      The 512-bit implementation of SHA-2
        
        //      Note that for 64-bit hashes, we're actually doing high-order, low-order, high-order, low-order.
        //      The 64-bit functions will assemble them into actual 64-bit "words".
        var hash = [
                0x6a09e667, 0xf3bcc908, 0xbb67ae85, 0x84caa73b, 0x3c6ef372, 0xfe94f82b, 0xa54ff53a, 0x5f1d36f1,
                0x510e527f, 0xade682d1, 0x9b05688c, 0x2b3e6c1f, 0x1f83d9ab, 0xfb41bd6b, 0x5be0cd19, 0x137e2179
        ];

        //      the exported function
        var SHA512 = function(/* String */data, /* sha64.outputTypes? */outputType){
                var out = outputType || sha64.outputTypes.Base64;
                data = sha64.stringToUtf8(data);
                var wa = sha64.digest(sha64.toWord(data), data.length * 8, hash, 512);
                switch(out){
                        case sha64.outputTypes.Raw: {
                                return wa;
                        }
                        case sha64.outputTypes.Hex: {
                                return sha64.toHex(wa);
                        }
                        case sha64.outputTypes.String: {
                                return sha64._toString(wa);
                        }
                        default: {
                                return sha64.toBase64(wa);
                        }
                }
        };
        SHA512._hmac = function(/* string */data, /* string */key, /* sha64.outputTypes? */outputType){
                var out = outputType || sha64.outputTypes.Base64;
                data = sha64.stringToUtf8(data);
                key = sha64.stringToUtf8(key);

                //      prepare the key
                var wa = sha64.toWord(key);
                if(wa.length > 16){
                        wa = sha64.digest(wa, key.length * 8, hash, 512);
                }

                //      set up the pads
                var ipad = new Array(16), opad = new Array(16);
                for(var i=0; i<16; i++){
                        ipad[i] = wa[i] ^ 0x36363636;
                        opad[i] = wa[i] ^ 0x5c5c5c5c;
                }

                //      make the final digest
                var r1 = sha64.digest(ipad.concat(sha64.toWord(data)), 512 + data.length * 8, hash, 512);
                var r2 = sha64.digest(opad.concat(r1), 512 + 160, hash, 512);

                //      return the output.
                switch(out){
                        case sha64.outputTypes.Raw: {
                                return wa;
                        }
                        case sha64.outputTypes.Hex: {
                                return sha64.toHex(wa);
                        }
                        case sha64.outputTypes.String: {
                                return sha64._toString(wa);
                        }
                        default: {
                                return sha64.toBase64(wa);
                        }
                }
        };
        return SHA512;
});