[Devtools] Add SHA-1 hash function in prep for URL hashing

third_party/WebKit/Source/devtools/front_end/product_registry/sha1.js

+// Copyright 2017 The Chromium Authors. All rights reserved.

[caseq, 2017/03/22 23:56:42]

Please just keep the original copyright.

[allada, 2017/03/23 01:26:16]

Done.

+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+/*
+ * A JavaScript implementation of the Secure Hash Algorithm, SHA-1, as defined
+ * in FIPS PUB 180-1
+ * Version 2.1a Copyright Paul Johnston 2000 - 2002.
+ * Other contributors: Greg Holt, Andrew Kepert, Ydnar, Lostinet
+ * Distributed under the BSD License
+ * See http://pajhome.org.uk/crypt/md5 for details.
+ */
+/**
+ * @param {string} str
+ * @return {string}
+ */
+ProductRegistry.sha1 = function(str) {
+  return binb2hex(core_sha1(str2binb(str), str.length * 8));
+
+  /**
+   * Calculate the SHA-1 of an array of big-endian words, and a bit length
+   * @param {!Array<number>} x
+   * @param {number} len
+   * @return {!Array<number>}
+   */
+  function core_sha1(x, len) {
+    /* append padding */
+    x[len >> 5] |= 0x80 << (24 - len % 32);
+    x[((len + 64 >> 9) << 4) + 15] = len;
+
+    var w = Array(80);
+    var a = 1732584193;
+    var b = -271733879;
+    var c = -1732584194;
+    var d = 271733878;
+    var e = -1009589776;
+
+    for (var i = 0; i < x.length; i += 16) {
+      var olda = a;
+      var oldb = b;
+      var oldc = c;
+      var oldd = d;
+      var olde = e;
+
+      for (var j = 0; j < 80; j++) {
+        if (j < 16)
+          w[j] = x[i + j];
+        else
+          w[j] = rol(w[j - 3] ^ w[j - 8] ^ w[j - 14] ^ w[j - 16], 1);
+        var t = safe_add(safe_add(rol(a, 5), sha1_ft(j, b, c, d)), safe_add(safe_add(e, w[j]), sha1_kt(j)));
+        e = d;
+        d = c;
+        c = rol(b, 30);
+        b = a;
+        a = t;
+      }
+
+      a = safe_add(a, olda);
+      b = safe_add(b, oldb);
+      c = safe_add(c, oldc);
+      d = safe_add(d, oldd);
+      e = safe_add(e, olde);
+    }
+    return Array(a, b, c, d, e);
+  }
+
+  /**
+   * Perform the appropriate triplet combination function for the current
+   * iteration
+   * @param {number} t
+   * @param {number} b
+   * @param {number} c
+   * @param {number} d
+   * @return {number}
+   */
+  function sha1_ft(t, b, c, d) {
+    if (t < 20)
+      return (b & c) | ((~b) & d);
+    if (t < 40)
+      return b ^ c ^ d;
+    if (t < 60)
+      return (b & c) | (b & d) | (c & d);
+    return b ^ c ^ d;
+  }
+
+  /**
+   * Determine the appropriate additive constant for the current iteration
+   * @param {number} t
+   * @return {number}
+   */
+  function sha1_kt(t) {
+    return (t < 20) ? 1518500249 : (t < 40) ? 1859775393 : (t < 60) ? -1894007588 : -899497514;
+  }
+
+  /**
+   * Add integers, wrapping at 2^32. This uses 16-bit operations internally
+   * to work around bugs in some JS interpreters.
+   * @param {number} x
+   * @param {number} y
+   * @return {number}
+   */
+  function safe_add(x, y) {
+    var lsw = (x & 0xFFFF) + (y & 0xFFFF);
+    var msw = (x >> 16) + (y >> 16) + (lsw >> 16);
+    return (msw << 16) | (lsw & 0xFFFF);
+  }
+
+  /**
+   * Bitwise rotate a 32-bit number to the left.
+   * @param {number} num
+   * @param {number} cnt
+   */
+  function rol(num, cnt) {
+    return (num << cnt) | (num >>> (32 - cnt));
+  }
+
+  /**
+   * Convert an 8-bit or 16-bit string to an array of big-endian words
+   * In 8-bit function, characters >255 have their hi-byte silently ignored.
+   * @param {string} str
+   * @return {!Array<number>}
+   */
+  function str2binb(str) {
+    var bin = Array();
+    var mask = 255;
+    for (var i = 0; i < str.length * 8; i += 8)
+      bin[i >> 5] |= (str.charCodeAt(i / 8) & mask) << (32 - 8 - i % 32);
+    return bin;
+  }
+
+  /**
+   * Convert an array of big-endian words to a hex string.
+   * @param {!Array<number>} binarray
+   * @return {string}
+   */
+  function binb2hex(binarray) {
+    const hex_tab = '0123456789abcdef';
+    var str = '';
+    for (var i = 0; i < binarray.length * 4; i++) {
+      str += hex_tab.charAt((binarray[i >> 2] >> ((3 - i % 4) * 8 + 4)) & 0xF) +
+          hex_tab.charAt((binarray[i >> 2] >> ((3 - i % 4) * 8)) & 0xF);
+    }
+    return str;
+  }
+};