gecko-dev/browser/components/loop/content/shared/libs/sjcl-dev20140604.js

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JavaScript

/** @fileOverview Javascript cryptography implementation.
*
* Crush to remove comments, shorten variable names and
* generally reduce transmission size.
*
* @author Emily Stark
* @author Mike Hamburg
* @author Dan Boneh
*/
"use strict";
/*jslint indent: 2, bitwise: false, nomen: false, plusplus: false, white: false, regexp: false */
/*global document, window, escape, unescape, module, require, Uint32Array */
/** @namespace The Stanford Javascript Crypto Library, top-level namespace. */
var sjcl = {
/** @namespace Symmetric ciphers. */
cipher: {},
/** @namespace Hash functions. Right now only SHA256 is implemented. */
hash: {},
/** @namespace Key exchange functions. Right now only SRP is implemented. */
keyexchange: {},
/** @namespace Block cipher modes of operation. */
mode: {},
/** @namespace Miscellaneous. HMAC and PBKDF2. */
misc: {},
/**
* @namespace Bit array encoders and decoders.
*
* @description
* The members of this namespace are functions which translate between
* SJCL's bitArrays and other objects (usually strings). Because it
* isn't always clear which direction is encoding and which is decoding,
* the method names are "fromBits" and "toBits".
*/
codec: {},
/** @namespace Exceptions. */
exception: {
/** @constructor Ciphertext is corrupt. */
corrupt: function(message) {
this.toString = function() { return "CORRUPT: "+this.message; };
this.message = message;
},
/** @constructor Invalid parameter. */
invalid: function(message) {
this.toString = function() { return "INVALID: "+this.message; };
this.message = message;
},
/** @constructor Bug or missing feature in SJCL. @constructor */
bug: function(message) {
this.toString = function() { return "BUG: "+this.message; };
this.message = message;
},
/** @constructor Something isn't ready. */
notReady: function(message) {
this.toString = function() { return "NOT READY: "+this.message; };
this.message = message;
}
}
};
if(typeof module !== 'undefined' && module.exports){
module.exports = sjcl;
}
/** @fileOverview Arrays of bits, encoded as arrays of Numbers.
*
* @author Emily Stark
* @author Mike Hamburg
* @author Dan Boneh
*/
/** @namespace Arrays of bits, encoded as arrays of Numbers.
*
* @description
* <p>
* These objects are the currency accepted by SJCL's crypto functions.
* </p>
*
* <p>
* Most of our crypto primitives operate on arrays of 4-byte words internally,
* but many of them can take arguments that are not a multiple of 4 bytes.
* This library encodes arrays of bits (whose size need not be a multiple of 8
* bits) as arrays of 32-bit words. The bits are packed, big-endian, into an
* array of words, 32 bits at a time. Since the words are double-precision
* floating point numbers, they fit some extra data. We use this (in a private,
* possibly-changing manner) to encode the number of bits actually present
* in the last word of the array.
* </p>
*
* <p>
* Because bitwise ops clear this out-of-band data, these arrays can be passed
* to ciphers like AES which want arrays of words.
* </p>
*/
sjcl.bitArray = {
/**
* Array slices in units of bits.
* @param {bitArray} a The array to slice.
* @param {Number} bstart The offset to the start of the slice, in bits.
* @param {Number} bend The offset to the end of the slice, in bits. If this is undefined,
* slice until the end of the array.
* @return {bitArray} The requested slice.
*/
bitSlice: function (a, bstart, bend) {
a = sjcl.bitArray._shiftRight(a.slice(bstart/32), 32 - (bstart & 31)).slice(1);
return (bend === undefined) ? a : sjcl.bitArray.clamp(a, bend-bstart);
},
/**
* Extract a number packed into a bit array.
* @param {bitArray} a The array to slice.
* @param {Number} bstart The offset to the start of the slice, in bits.
* @param {Number} length The length of the number to extract.
* @return {Number} The requested slice.
*/
extract: function(a, bstart, blength) {
// FIXME: this Math.floor is not necessary at all, but for some reason
// seems to suppress a bug in the Chromium JIT.
var x, sh = Math.floor((-bstart-blength) & 31);
if ((bstart + blength - 1 ^ bstart) & -32) {
// it crosses a boundary
x = (a[bstart/32|0] << (32 - sh)) ^ (a[bstart/32+1|0] >>> sh);
} else {
// within a single word
x = a[bstart/32|0] >>> sh;
}
return x & ((1<<blength) - 1);
},
/**
* Concatenate two bit arrays.
* @param {bitArray} a1 The first array.
* @param {bitArray} a2 The second array.
* @return {bitArray} The concatenation of a1 and a2.
*/
concat: function (a1, a2) {
if (a1.length === 0 || a2.length === 0) {
return a1.concat(a2);
}
var last = a1[a1.length-1], shift = sjcl.bitArray.getPartial(last);
if (shift === 32) {
return a1.concat(a2);
} else {
return sjcl.bitArray._shiftRight(a2, shift, last|0, a1.slice(0,a1.length-1));
}
},
/**
* Find the length of an array of bits.
* @param {bitArray} a The array.
* @return {Number} The length of a, in bits.
*/
bitLength: function (a) {
var l = a.length, x;
if (l === 0) { return 0; }
x = a[l - 1];
return (l-1) * 32 + sjcl.bitArray.getPartial(x);
},
/**
* Truncate an array.
* @param {bitArray} a The array.
* @param {Number} len The length to truncate to, in bits.
* @return {bitArray} A new array, truncated to len bits.
*/
clamp: function (a, len) {
if (a.length * 32 < len) { return a; }
a = a.slice(0, Math.ceil(len / 32));
var l = a.length;
len = len & 31;
if (l > 0 && len) {
a[l-1] = sjcl.bitArray.partial(len, a[l-1] & 0x80000000 >> (len-1), 1);
}
return a;
},
/**
* Make a partial word for a bit array.
* @param {Number} len The number of bits in the word.
* @param {Number} x The bits.
* @param {Number} [0] _end Pass 1 if x has already been shifted to the high side.
* @return {Number} The partial word.
*/
partial: function (len, x, _end) {
if (len === 32) { return x; }
return (_end ? x|0 : x << (32-len)) + len * 0x10000000000;
},
/**
* Get the number of bits used by a partial word.
* @param {Number} x The partial word.
* @return {Number} The number of bits used by the partial word.
*/
getPartial: function (x) {
return Math.round(x/0x10000000000) || 32;
},
/**
* Compare two arrays for equality in a predictable amount of time.
* @param {bitArray} a The first array.
* @param {bitArray} b The second array.
* @return {boolean} true if a == b; false otherwise.
*/
equal: function (a, b) {
if (sjcl.bitArray.bitLength(a) !== sjcl.bitArray.bitLength(b)) {
return false;
}
var x = 0, i;
for (i=0; i<a.length; i++) {
x |= a[i]^b[i];
}
return (x === 0);
},
/** Shift an array right.
* @param {bitArray} a The array to shift.
* @param {Number} shift The number of bits to shift.
* @param {Number} [carry=0] A byte to carry in
* @param {bitArray} [out=[]] An array to prepend to the output.
* @private
*/
_shiftRight: function (a, shift, carry, out) {
var i, last2=0, shift2;
if (out === undefined) { out = []; }
for (; shift >= 32; shift -= 32) {
out.push(carry);
carry = 0;
}
if (shift === 0) {
return out.concat(a);
}
for (i=0; i<a.length; i++) {
out.push(carry | a[i]>>>shift);
carry = a[i] << (32-shift);
}
last2 = a.length ? a[a.length-1] : 0;
shift2 = sjcl.bitArray.getPartial(last2);
out.push(sjcl.bitArray.partial(shift+shift2 & 31, (shift + shift2 > 32) ? carry : out.pop(),1));
return out;
},
/** xor a block of 4 words together.
* @private
*/
_xor4: function(x,y) {
return [x[0]^y[0],x[1]^y[1],x[2]^y[2],x[3]^y[3]];
}
};
/** @fileOverview Bit array codec implementations.
*
* @author Emily Stark
* @author Mike Hamburg
* @author Dan Boneh
*/
/** @namespace UTF-8 strings */
sjcl.codec.utf8String = {
/** Convert from a bitArray to a UTF-8 string. */
fromBits: function (arr) {
var out = "", bl = sjcl.bitArray.bitLength(arr), i, tmp;
for (i=0; i<bl/8; i++) {
if ((i&3) === 0) {
tmp = arr[i/4];
}
out += String.fromCharCode(tmp >>> 24);
tmp <<= 8;
}
return decodeURIComponent(escape(out));
},
/** Convert from a UTF-8 string to a bitArray. */
toBits: function (str) {
str = unescape(encodeURIComponent(str));
var out = [], i, tmp=0;
for (i=0; i<str.length; i++) {
tmp = tmp << 8 | str.charCodeAt(i);
if ((i&3) === 3) {
out.push(tmp);
tmp = 0;
}
}
if (i&3) {
out.push(sjcl.bitArray.partial(8*(i&3), tmp));
}
return out;
}
};
/** @fileOverview Bit array codec implementations.
*
* @author Emily Stark
* @author Mike Hamburg
* @author Dan Boneh
*/
/** @namespace Hexadecimal */
sjcl.codec.hex = {
/** Convert from a bitArray to a hex string. */
fromBits: function (arr) {
var out = "", i;
for (i=0; i<arr.length; i++) {
out += ((arr[i]|0)+0xF00000000000).toString(16).substr(4);
}
return out.substr(0, sjcl.bitArray.bitLength(arr)/4);//.replace(/(.{8})/g, "$1 ");
},
/** Convert from a hex string to a bitArray. */
toBits: function (str) {
var i, out=[], len;
str = str.replace(/\s|0x/g, "");
len = str.length;
str = str + "00000000";
for (i=0; i<str.length; i+=8) {
out.push(parseInt(str.substr(i,8),16)^0);
}
return sjcl.bitArray.clamp(out, len*4);
}
};
/** @fileOverview Javascript SHA-256 implementation.
*
* An older version of this implementation is available in the public
* domain, but this one is (c) Emily Stark, Mike Hamburg, Dan Boneh,
* Stanford University 2008-2010 and BSD-licensed for liability
* reasons.
*
* Special thanks to Aldo Cortesi for pointing out several bugs in
* this code.
*
* @author Emily Stark
* @author Mike Hamburg
* @author Dan Boneh
*/
/**
* Context for a SHA-256 operation in progress.
* @constructor
* @class Secure Hash Algorithm, 256 bits.
*/
sjcl.hash.sha256 = function (hash) {
if (!this._key[0]) { this._precompute(); }
if (hash) {
this._h = hash._h.slice(0);
this._buffer = hash._buffer.slice(0);
this._length = hash._length;
} else {
this.reset();
}
};
/**
* Hash a string or an array of words.
* @static
* @param {bitArray|String} data the data to hash.
* @return {bitArray} The hash value, an array of 16 big-endian words.
*/
sjcl.hash.sha256.hash = function (data) {
return (new sjcl.hash.sha256()).update(data).finalize();
};
sjcl.hash.sha256.prototype = {
/**
* The hash's block size, in bits.
* @constant
*/
blockSize: 512,
/**
* Reset the hash state.
* @return this
*/
reset:function () {
this._h = this._init.slice(0);
this._buffer = [];
this._length = 0;
return this;
},
/**
* Input several words to the hash.
* @param {bitArray|String} data the data to hash.
* @return this
*/
update: function (data) {
if (typeof data === "string") {
data = sjcl.codec.utf8String.toBits(data);
}
var i, b = this._buffer = sjcl.bitArray.concat(this._buffer, data),
ol = this._length,
nl = this._length = ol + sjcl.bitArray.bitLength(data);
for (i = 512+ol & -512; i <= nl; i+= 512) {
this._block(b.splice(0,16));
}
return this;
},
/**
* Complete hashing and output the hash value.
* @return {bitArray} The hash value, an array of 8 big-endian words.
*/
finalize:function () {
var i, b = this._buffer, h = this._h;
// Round out and push the buffer
b = sjcl.bitArray.concat(b, [sjcl.bitArray.partial(1,1)]);
// Round out the buffer to a multiple of 16 words, less the 2 length words.
for (i = b.length + 2; i & 15; i++) {
b.push(0);
}
// append the length
b.push(Math.floor(this._length / 0x100000000));
b.push(this._length | 0);
while (b.length) {
this._block(b.splice(0,16));
}
this.reset();
return h;
},
/**
* The SHA-256 initialization vector, to be precomputed.
* @private
*/
_init:[],
/*
_init:[0x6a09e667,0xbb67ae85,0x3c6ef372,0xa54ff53a,0x510e527f,0x9b05688c,0x1f83d9ab,0x5be0cd19],
*/
/**
* The SHA-256 hash key, to be precomputed.
* @private
*/
_key:[],
/*
_key:
[0x428a2f98, 0x71374491, 0xb5c0fbcf, 0xe9b5dba5, 0x3956c25b, 0x59f111f1, 0x923f82a4, 0xab1c5ed5,
0xd807aa98, 0x12835b01, 0x243185be, 0x550c7dc3, 0x72be5d74, 0x80deb1fe, 0x9bdc06a7, 0xc19bf174,
0xe49b69c1, 0xefbe4786, 0x0fc19dc6, 0x240ca1cc, 0x2de92c6f, 0x4a7484aa, 0x5cb0a9dc, 0x76f988da,
0x983e5152, 0xa831c66d, 0xb00327c8, 0xbf597fc7, 0xc6e00bf3, 0xd5a79147, 0x06ca6351, 0x14292967,
0x27b70a85, 0x2e1b2138, 0x4d2c6dfc, 0x53380d13, 0x650a7354, 0x766a0abb, 0x81c2c92e, 0x92722c85,
0xa2bfe8a1, 0xa81a664b, 0xc24b8b70, 0xc76c51a3, 0xd192e819, 0xd6990624, 0xf40e3585, 0x106aa070,
0x19a4c116, 0x1e376c08, 0x2748774c, 0x34b0bcb5, 0x391c0cb3, 0x4ed8aa4a, 0x5b9cca4f, 0x682e6ff3,
0x748f82ee, 0x78a5636f, 0x84c87814, 0x8cc70208, 0x90befffa, 0xa4506ceb, 0xbef9a3f7, 0xc67178f2],
*/
/**
* Function to precompute _init and _key.
* @private
*/
_precompute: function () {
var i = 0, prime = 2, factor;
function frac(x) { return (x-Math.floor(x)) * 0x100000000 | 0; }
outer: for (; i<64; prime++) {
for (factor=2; factor*factor <= prime; factor++) {
if (prime % factor === 0) {
// not a prime
continue outer;
}
}
if (i<8) {
this._init[i] = frac(Math.pow(prime, 1/2));
}
this._key[i] = frac(Math.pow(prime, 1/3));
i++;
}
},
/**
* Perform one cycle of SHA-256.
* @param {bitArray} words one block of words.
* @private
*/
_block:function (words) {
var i, tmp, a, b,
w = words.slice(0),
h = this._h,
k = this._key,
h0 = h[0], h1 = h[1], h2 = h[2], h3 = h[3],
h4 = h[4], h5 = h[5], h6 = h[6], h7 = h[7];
/* Rationale for placement of |0 :
* If a value can overflow is original 32 bits by a factor of more than a few
* million (2^23 ish), there is a possibility that it might overflow the
* 53-bit mantissa and lose precision.
*
* To avoid this, we clamp back to 32 bits by |'ing with 0 on any value that
* propagates around the loop, and on the hash state h[]. I don't believe
* that the clamps on h4 and on h0 are strictly necessary, but it's close
* (for h4 anyway), and better safe than sorry.
*
* The clamps on h[] are necessary for the output to be correct even in the
* common case and for short inputs.
*/
for (i=0; i<64; i++) {
// load up the input word for this round
if (i<16) {
tmp = w[i];
} else {
a = w[(i+1 ) & 15];
b = w[(i+14) & 15];
tmp = w[i&15] = ((a>>>7 ^ a>>>18 ^ a>>>3 ^ a<<25 ^ a<<14) +
(b>>>17 ^ b>>>19 ^ b>>>10 ^ b<<15 ^ b<<13) +
w[i&15] + w[(i+9) & 15]) | 0;
}
tmp = (tmp + h7 + (h4>>>6 ^ h4>>>11 ^ h4>>>25 ^ h4<<26 ^ h4<<21 ^ h4<<7) + (h6 ^ h4&(h5^h6)) + k[i]); // | 0;
// shift register
h7 = h6; h6 = h5; h5 = h4;
h4 = h3 + tmp | 0;
h3 = h2; h2 = h1; h1 = h0;
h0 = (tmp + ((h1&h2) ^ (h3&(h1^h2))) + (h1>>>2 ^ h1>>>13 ^ h1>>>22 ^ h1<<30 ^ h1<<19 ^ h1<<10)) | 0;
}
h[0] = h[0]+h0 | 0;
h[1] = h[1]+h1 | 0;
h[2] = h[2]+h2 | 0;
h[3] = h[3]+h3 | 0;
h[4] = h[4]+h4 | 0;
h[5] = h[5]+h5 | 0;
h[6] = h[6]+h6 | 0;
h[7] = h[7]+h7 | 0;
}
};
/** @fileOverview HMAC implementation.
*
* @author Emily Stark
* @author Mike Hamburg
* @author Dan Boneh
*/
/** HMAC with the specified hash function.
* @constructor
* @param {bitArray} key the key for HMAC.
* @param {Object} [hash=sjcl.hash.sha256] The hash function to use.
*/
sjcl.misc.hmac = function (key, Hash) {
this._hash = Hash = Hash || sjcl.hash.sha256;
var exKey = [[],[]], i,
bs = Hash.prototype.blockSize / 32;
this._baseHash = [new Hash(), new Hash()];
if (key.length > bs) {
key = Hash.hash(key);
}
for (i=0; i<bs; i++) {
exKey[0][i] = key[i]^0x36363636;
exKey[1][i] = key[i]^0x5C5C5C5C;
}
this._baseHash[0].update(exKey[0]);
this._baseHash[1].update(exKey[1]);
this._resultHash = new Hash(this._baseHash[0]);
};
/** HMAC with the specified hash function. Also called encrypt since it's a prf.
* @param {bitArray|String} data The data to mac.
*/
sjcl.misc.hmac.prototype.encrypt = sjcl.misc.hmac.prototype.mac = function (data) {
if (!this._updated) {
this.update(data);
return this.digest(data);
} else {
throw new sjcl.exception.invalid("encrypt on already updated hmac called!");
}
};
sjcl.misc.hmac.prototype.reset = function () {
this._resultHash = new this._hash(this._baseHash[0]);
this._updated = false;
};
sjcl.misc.hmac.prototype.update = function (data) {
this._updated = true;
this._resultHash.update(data);
};
sjcl.misc.hmac.prototype.digest = function () {
var w = this._resultHash.finalize(), result = new (this._hash)(this._baseHash[1]).update(w).finalize();
this.reset();
return result;
};