chrome/test/data/third_party/kraken/tests/kraken-1.1/stanford-crypto-sha256-iterative.js

   1 /**
   2  * Test SHA-256 using an ad-hoc iterative technique.
   3  * This uses a string buffer which has n characters on the nth iteration.
   4  * Each iteration, the buffer is hashed and the hash is converted to a string.
   5  * The first two characters of the string are prepended to the buffer, then the
   6  * last character of the buffer is removed.  This way, neither the beginning nor
   7  * the end of the buffer is fixed.
   8  *
   9  * The hashes from each output step are also hashed together into one final hash.
  10  * This is compared against a final hash which was computed with SSL.
  11  */
  12
  13 new sjcl.test.TestCase("SHA-256 iterative", function (cb) {
  14   if (!sjcl.hash.sha256) {
  15     this.unimplemented();
  16     cb && cb();
  17     return;
  18   }
  19
  20   var toBeHashed = "", cumulative = new sjcl.hash.sha256(), hash, thiz=this;
  21   browserUtil.cpsIterate(function (i, cbb) {
  22     for (var n=100*i; n<100*(i+1); n++) {
  23       hash = sjcl.hash.sha256.hash(toBeHashed);
  24       hash = sjcl.codec.hex.fromBits(hash);
  25       cumulative.update(hash);
  26       toBeHashed = (hash.substring(0,2)+toBeHashed).substring(0,n+1);
  27     }
  28     cbb && cbb();
  29   }, 0, 10, true, function () {
  30     hash = sjcl.codec.hex.fromBits(cumulative.finalize());
  31     thiz.require(hash === "f305c76d5d457ddf04f1927166f5e13429407049a5c5f29021916321fcdcd8b4");
  32     cb && cb();
  33   });
  34 });
  35
  36 sjcl.test.run();