// Copyright (c) 2005 Tom Wu // All Rights Reserved. // See "LICENSE" for details. // Basic JavaScript BN library - subset useful for RSA encryption. // Bits per digit var dbits; // JavaScript engine analysis var canary = 0xdeadbeefcafe; var j_lm = ((canary & 0xffffff) == 0xefcafe); // (public) Constructor function BigInteger(a, b, c) { if (a != null) if ("number" == typeof a) this.fromNumber(a, b, c); else if (b == null && "string" != typeof a) this.fromString(a, 256); else this.fromString(a, b); } // return new, unset BigInteger function nbi() { return new BigInteger(null); } // am: Compute w_j += (x*this_i), propagate carries, // c is initial carry, returns final carry. // c < 3*dvalue, x < 2*dvalue, this_i < dvalue // We need to select the fastest one that works in this environment. // am1: use a single mult and divide to get the high bits, // max digit bits should be 26 because // max internal value = 2*dvalue^2-2*dvalue (< 2^53) function am1(i, x, w, j, c, n) { while (--n >= 0) { var v = x * this[i++] + w[j] + c; c = Math.floor(v / 0x4000000); w[j++] = v & 0x3ffffff; } return c; } // am2 avoids a big mult-and-extract completely. // Max digit bits should be <= 30 because we do bitwise ops // on values up to 2*hdvalue^2-hdvalue-1 (< 2^31) function am2(i, x, w, j, c, n) { var xl = x & 0x7fff, xh = x >> 15; while (--n >= 0) { var l = this[i] & 0x7fff; var h = this[i++] >> 15; var m = xh * l + h * xl; l = xl * l + ((m & 0x7fff) << 15) + w[j] + (c & 0x3fffffff); c = (l >>> 30) + (m >>> 15) + xh * h + (c >>> 30); w[j++] = l & 0x3fffffff; } return c; } // Alternately, set max digit bits to 28 since some // browsers slow down when dealing with 32-bit numbers. function am3(i, x, w, j, c, n) { var xl = x & 0x3fff, xh = x >> 14; while (--n >= 0) { var l = this[i] & 0x3fff; var h = this[i++] >> 14; var m = xh * l + h * xl; l = xl * l + ((m & 0x3fff) << 14) + w[j] + c; c = (l >> 28) + (m >> 14) + xh * h; w[j++] = l & 0xfffffff; } return c; } if (j_lm && (navigator.appName == "Microsoft Internet Explorer")) { BigInteger.prototype.am = am2; dbits = 30; } else if (j_lm && (navigator.appName != "Netscape")) { BigInteger.prototype.am = am1; dbits = 26; } else { // Mozilla/Netscape seems to prefer am3 BigInteger.prototype.am = am3; dbits = 28; } BigInteger.prototype.DB = dbits; BigInteger.prototype.DM = ((1 << dbits) - 1); BigInteger.prototype.DV = (1 << dbits); var BI_FP = 52; BigInteger.prototype.FV = Math.pow(2, BI_FP); BigInteger.prototype.F1 = BI_FP - dbits; BigInteger.prototype.F2 = 2 * dbits - BI_FP; // Digit conversions var BI_RM = "0123456789abcdefghijklmnopqrstuvwxyz"; var BI_RC = new Array(); var rr, vv; rr = "0".charCodeAt(0); for (vv = 0; vv <= 9; ++vv) BI_RC[rr++] = vv; rr = "a".charCodeAt(0); for (vv = 10; vv < 36; ++vv) BI_RC[rr++] = vv; rr = "A".charCodeAt(0); for (vv = 10; vv < 36; ++vv) BI_RC[rr++] = vv; function int2char(n) { return BI_RM.charAt(n); } function intAt(s, i) { var c = BI_RC[s.charCodeAt(i)]; return (c == null) ? -1 : c; } // (protected) copy this to r function bnpCopyTo(r) { for ( var i = this.t - 1; i >= 0; --i) r[i] = this[i]; r.t = this.t; r.s = this.s; } // (protected) set from integer value x, -DV <= x < DV function bnpFromInt(x) { this.t = 1; this.s = (x < 0) ? -1 : 0; if (x > 0) this[0] = x; else if (x < -1) this[0] = x + DV; else this.t = 0; } // return bigint initialized to value function nbv(i) { var r = nbi(); r.fromInt(i); return r; } // (protected) set from string and radix function bnpFromString(s, b) { var k; if (b == 16) k = 4; else if (b == 8) k = 3; else if (b == 256) k = 8; // byte array else if (b == 2) k = 1; else if (b == 32) k = 5; else if (b == 4) k = 2; else { this.fromRadix(s, b); return; } this.t = 0; this.s = 0; var i = s.length, mi = false, sh = 0; while (--i >= 0) { var x = (k == 8) ? s[i] & 0xff : intAt(s, i); if (x < 0) { if (s.charAt(i) == "-") mi = true; continue; } mi = false; if (sh == 0) this[this.t++] = x; else if (sh + k > this.DB) { this[this.t - 1] |= (x & ((1 << (this.DB - sh)) - 1)) << sh; this[this.t++] = (x >> (this.DB - sh)); } else this[this.t - 1] |= x << sh; sh += k; if (sh >= this.DB) sh -= this.DB; } if (k == 8 && (s[0] & 0x80) != 0) { this.s = -1; if (sh > 0) this[this.t - 1] |= ((1 << (this.DB - sh)) - 1) << sh; } this.clamp(); if (mi) BigInteger.ZERO.subTo(this, this); } // (protected) clamp off excess high words function bnpClamp() { var c = this.s & this.DM; while (this.t > 0 && this[this.t - 1] == c) --this.t; } // (public) return string representation in given radix function bnToString(b) { if (this.s < 0) return "-" + this.negate().toString(b); var k; if (b == 16) k = 4; else if (b == 8) k = 3; else if (b == 2) k = 1; else if (b == 32) k = 5; else if (b == 4) k = 2; else return this.toRadix(b); var km = (1 << k) - 1, d, m = false, r = "", i = this.t; var p = this.DB - (i * this.DB) % k; if (i-- > 0) { if (p < this.DB && (d = this[i] >> p) > 0) { m = true; r = int2char(d); } while (i >= 0) { if (p < k) { d = (this[i] & ((1 << p) - 1)) << (k - p); d |= this[--i] >> (p += this.DB - k); } else { d = (this[i] >> (p -= k)) & km; if (p <= 0) { p += this.DB; --i; } } if (d > 0) m = true; if (m) r += int2char(d); } } return m ? r : "0"; } // (public) -this function bnNegate() { var r = nbi(); BigInteger.ZERO.subTo(this, r); return r; } // (public) |this| function bnAbs() { return (this.s < 0) ? this.negate() : this; } // (public) return + if this > a, - if this < a, 0 if equal function bnCompareTo(a) { var r = this.s - a.s; if (r != 0) return r; var i = this.t; r = i - a.t; if (r != 0) return r; while (--i >= 0) if ((r = this[i] - a[i]) != 0) return r; return 0; } // returns bit length of the integer x function nbits(x) { var r = 1, t; if ((t = x >>> 16) != 0) { x = t; r += 16; } if ((t = x >> 8) != 0) { x = t; r += 8; } if ((t = x >> 4) != 0) { x = t; r += 4; } if ((t = x >> 2) != 0) { x = t; r += 2; } if ((t = x >> 1) != 0) { x = t; r += 1; } return r; } // (public) return the number of bits in "this" function bnBitLength() { if (this.t <= 0) return 0; return this.DB * (this.t - 1) + nbits(this[this.t - 1] ^ (this.s & this.DM)); } // (protected) r = this << n*DB function bnpDLShiftTo(n, r) { var i; for (i = this.t - 1; i >= 0; --i) r[i + n] = this[i]; for (i = n - 1; i >= 0; --i) r[i] = 0; r.t = this.t + n; r.s = this.s; } // (protected) r = this >> n*DB function bnpDRShiftTo(n, r) { for ( var i = n; i < this.t; ++i) r[i - n] = this[i]; r.t = Math.max(this.t - n, 0); r.s = this.s; } // (protected) r = this << n function bnpLShiftTo(n, r) { var bs = n % this.DB; var cbs = this.DB - bs; var bm = (1 << cbs) - 1; var ds = Math.floor(n / this.DB), c = (this.s << bs) & this.DM, i; for (i = this.t - 1; i >= 0; --i) { r[i + ds + 1] = (this[i] >> cbs) | c; c = (this[i] & bm) << bs; } for (i = ds - 1; i >= 0; --i) r[i] = 0; r[ds] = c; r.t = this.t + ds + 1; r.s = this.s; r.clamp(); } // (protected) r = this >> n function bnpRShiftTo(n, r) { r.s = this.s; var ds = Math.floor(n / this.DB); if (ds >= this.t) { r.t = 0; return; } var bs = n % this.DB; var cbs = this.DB - bs; var bm = (1 << bs) - 1; r[0] = this[ds] >> bs; for ( var i = ds + 1; i < this.t; ++i) { r[i - ds - 1] |= (this[i] & bm) << cbs; r[i - ds] = this[i] >> bs; } if (bs > 0) r[this.t - ds - 1] |= (this.s & bm) << cbs; r.t = this.t - ds; r.clamp(); } // (protected) r = this - a function bnpSubTo(a, r) { var i = 0, c = 0, m = Math.min(a.t, this.t); while (i < m) { c += this[i] - a[i]; r[i++] = c & this.DM; c >>= this.DB; } if (a.t < this.t) { c -= a.s; while (i < this.t) { c += this[i]; r[i++] = c & this.DM; c >>= this.DB; } c += this.s; } else { c += this.s; while (i < a.t) { c -= a[i]; r[i++] = c & this.DM; c >>= this.DB; } c -= a.s; } r.s = (c < 0) ? -1 : 0; if (c < -1) r[i++] = this.DV + c; else if (c > 0) r[i++] = c; r.t = i; r.clamp(); } // (protected) r = this * a, r != this,a (HAC 14.12) // "this" should be the larger one if appropriate. function bnpMultiplyTo(a, r) { var x = this.abs(), y = a.abs(); var i = x.t; r.t = i + y.t; while (--i >= 0) r[i] = 0; for (i = 0; i < y.t; ++i) r[i + x.t] = x.am(0, y[i], r, i, 0, x.t); r.s = 0; r.clamp(); if (this.s != a.s) BigInteger.ZERO.subTo(r, r); } // (protected) r = this^2, r != this (HAC 14.16) function bnpSquareTo(r) { var x = this.abs(); var i = r.t = 2 * x.t; while (--i >= 0) r[i] = 0; for (i = 0; i < x.t - 1; ++i) { var c = x.am(i, x[i], r, 2 * i, 0, 1); if ((r[i + x.t] += x.am(i + 1, 2 * x[i], r, 2 * i + 1, c, x.t - i - 1)) >= x.DV) { r[i + x.t] -= x.DV; r[i + x.t + 1] = 1; } } if (r.t > 0) r[r.t - 1] += x.am(i, x[i], r, 2 * i, 0, 1); r.s = 0; r.clamp(); } // (protected) divide this by m, quotient and remainder to q, r (HAC 14.20) // r != q, this != m. q or r may be null. function bnpDivRemTo(m, q, r) { var pm = m.abs(); if (pm.t <= 0) return; var pt = this.abs(); if (pt.t < pm.t) { if (q != null) q.fromInt(0); if (r != null) this.copyTo(r); return; } if (r == null) r = nbi(); var y = nbi(), ts = this.s, ms = m.s; var nsh = this.DB - nbits(pm[pm.t - 1]); // normalize modulus if (nsh > 0) { pm.lShiftTo(nsh, y); pt.lShiftTo(nsh, r); } else { pm.copyTo(y); pt.copyTo(r); } var ys = y.t; var y0 = y[ys - 1]; if (y0 == 0) return; var yt = y0 * (1 << this.F1) + ((ys > 1) ? y[ys - 2] >> this.F2 : 0); var d1 = this.FV / yt, d2 = (1 << this.F1) / yt, e = 1 << this.F2; var i = r.t, j = i - ys, t = (q == null) ? nbi() : q; y.dlShiftTo(j, t); if (r.compareTo(t) >= 0) { r[r.t++] = 1; r.subTo(t, r); } BigInteger.ONE.dlShiftTo(ys, t); t.subTo(y, y); // "negative" y so we can replace sub with am later while (y.t < ys) y[y.t++] = 0; while (--j >= 0) { // Estimate quotient digit var qd = (r[--i] == y0) ? this.DM : Math.floor(r[i] * d1 + (r[i - 1] + e) * d2); if ((r[i] += y.am(0, qd, r, j, 0, ys)) < qd) { // Try it out y.dlShiftTo(j, t); r.subTo(t, r); while (r[i] < --qd) r.subTo(t, r); } } if (q != null) { r.drShiftTo(ys, q); if (ts != ms) BigInteger.ZERO.subTo(q, q); } r.t = ys; r.clamp(); if (nsh > 0) r.rShiftTo(nsh, r); // Denormalize remainder if (ts < 0) BigInteger.ZERO.subTo(r, r); } // (public) this mod a function bnMod(a) { var r = nbi(); this.abs().divRemTo(a, null, r); if (this.s < 0 && r.compareTo(BigInteger.ZERO) > 0) a.subTo(r, r); return r; } // Modular reduction using "classic" algorithm function Classic(m) { this.m = m; } function cConvert(x) { if (x.s < 0 || x.compareTo(this.m) >= 0) return x.mod(this.m); else return x; } function cRevert(x) { return x; } function cReduce(x) { x.divRemTo(this.m, null, x); } function cMulTo(x, y, r) { x.multiplyTo(y, r); this.reduce(r); } function cSqrTo(x, r) { x.squareTo(r); this.reduce(r); } Classic.prototype.convert = cConvert; Classic.prototype.revert = cRevert; Classic.prototype.reduce = cReduce; Classic.prototype.mulTo = cMulTo; Classic.prototype.sqrTo = cSqrTo; // (protected) return "-1/this % 2^DB"; useful for Mont. reduction // justification: // xy == 1 (mod m) // xy = 1+km // xy(2-xy) = (1+km)(1-km) // x[y(2-xy)] = 1-k^2m^2 // x[y(2-xy)] == 1 (mod m^2) // if y is 1/x mod m, then y(2-xy) is 1/x mod m^2 // should reduce x and y(2-xy) by m^2 at each step to keep size bounded. // JS multiply "overflows" differently from C/C++, so care is needed here. function bnpInvDigit() { if (this.t < 1) return 0; var x = this[0]; if ((x & 1) == 0) return 0; var y = x & 3; // y == 1/x mod 2^2 y = (y * (2 - (x & 0xf) * y)) & 0xf; // y == 1/x mod 2^4 y = (y * (2 - (x & 0xff) * y)) & 0xff; // y == 1/x mod 2^8 y = (y * (2 - (((x & 0xffff) * y) & 0xffff))) & 0xffff; // y == 1/x mod 2^16 // last step - calculate inverse mod DV directly; // assumes 16 < DB <= 32 and assumes ability to handle 48-bit ints y = (y * (2 - x * y % this.DV)) % this.DV; // y == 1/x mod 2^dbits // we really want the negative inverse, and -DV < y < DV return (y > 0) ? this.DV - y : -y; } // Montgomery reduction function Montgomery(m) { this.m = m; this.mp = m.invDigit(); this.mpl = this.mp & 0x7fff; this.mph = this.mp >> 15; this.um = (1 << (m.DB - 15)) - 1; this.mt2 = 2 * m.t; } // xR mod m function montConvert(x) { var r = nbi(); x.abs().dlShiftTo(this.m.t, r); r.divRemTo(this.m, null, r); if (x.s < 0 && r.compareTo(BigInteger.ZERO) > 0) this.m.subTo(r, r); return r; } // x/R mod m function montRevert(x) { var r = nbi(); x.copyTo(r); this.reduce(r); return r; } // x = x/R mod m (HAC 14.32) function montReduce(x) { while (x.t <= this.mt2) // pad x so am has enough room later x[x.t++] = 0; for ( var i = 0; i < this.m.t; ++i) { // faster way of calculating u0 = x[i]*mp mod DV var j = x[i] & 0x7fff; var u0 = (j * this.mpl + (((j * this.mph + (x[i] >> 15) * this.mpl) & this.um) << 15)) & x.DM; // use am to combine the multiply-shift-add into one call j = i + this.m.t; x[j] += this.m.am(0, u0, x, i, 0, this.m.t); // propagate carry while (x[j] >= x.DV) { x[j] -= x.DV; x[++j]++; } } x.clamp(); x.drShiftTo(this.m.t, x); if (x.compareTo(this.m) >= 0) x.subTo(this.m, x); } // r = "x^2/R mod m"; x != r function montSqrTo(x, r) { x.squareTo(r); this.reduce(r); } // r = "xy/R mod m"; x,y != r function montMulTo(x, y, r) { x.multiplyTo(y, r); this.reduce(r); } Montgomery.prototype.convert = montConvert; Montgomery.prototype.revert = montRevert; Montgomery.prototype.reduce = montReduce; Montgomery.prototype.mulTo = montMulTo; Montgomery.prototype.sqrTo = montSqrTo; // (protected) true iff this is even function bnpIsEven() { return ((this.t > 0) ? (this[0] & 1) : this.s) == 0; } // (protected) this^e, e < 2^32, doing sqr and mul with "r" (HAC 14.79) function bnpExp(e, z) { if (e > 0xffffffff || e < 1) return BigInteger.ONE; var r = nbi(), r2 = nbi(), g = z.convert(this), i = nbits(e) - 1; g.copyTo(r); while (--i >= 0) { z.sqrTo(r, r2); if ((e & (1 << i)) > 0) z.mulTo(r2, g, r); else { var t = r; r = r2; r2 = t; } } return z.revert(r); } // (public) this^e % m, 0 <= e < 2^32 function bnModPowInt(e, m) { var z; if (e < 256 || m.isEven()) z = new Classic(m); else z = new Montgomery(m); return this.exp(e, z); } // protected BigInteger.prototype.copyTo = bnpCopyTo; BigInteger.prototype.fromInt = bnpFromInt; BigInteger.prototype.fromString = bnpFromString; BigInteger.prototype.clamp = bnpClamp; BigInteger.prototype.dlShiftTo = bnpDLShiftTo; BigInteger.prototype.drShiftTo = bnpDRShiftTo; BigInteger.prototype.lShiftTo = bnpLShiftTo; BigInteger.prototype.rShiftTo = bnpRShiftTo; BigInteger.prototype.subTo = bnpSubTo; BigInteger.prototype.multiplyTo = bnpMultiplyTo; BigInteger.prototype.squareTo = bnpSquareTo; BigInteger.prototype.divRemTo = bnpDivRemTo; BigInteger.prototype.invDigit = bnpInvDigit; BigInteger.prototype.isEven = bnpIsEven; BigInteger.prototype.exp = bnpExp; // public BigInteger.prototype.toString = bnToString; BigInteger.prototype.negate = bnNegate; BigInteger.prototype.abs = bnAbs; BigInteger.prototype.compareTo = bnCompareTo; BigInteger.prototype.bitLength = bnBitLength; BigInteger.prototype.mod = bnMod; BigInteger.prototype.modPowInt = bnModPowInt; // "constants" BigInteger.ZERO = nbv(0); BigInteger.ONE = nbv(1); // prng4.js - uses Arcfour as a PRNG function Arcfour() { this.i = 0; this.j = 0; this.S = new Array(); } // Initialize arcfour context from key, an array of ints, each from [0..255] function ARC4init(key) { var i, j, t; for (i = 0; i < 256; ++i) this.S[i] = i; j = 0; for (i = 0; i < 256; ++i) { j = (j + this.S[i] + key[i % key.length]) & 255; t = this.S[i]; this.S[i] = this.S[j]; this.S[j] = t; } this.i = 0; this.j = 0; } function ARC4next() { var t; this.i = (this.i + 1) & 255; this.j = (this.j + this.S[this.i]) & 255; t = this.S[this.i]; this.S[this.i] = this.S[this.j]; this.S[this.j] = t; return this.S[(t + this.S[this.i]) & 255]; } Arcfour.prototype.init = ARC4init; Arcfour.prototype.next = ARC4next; // Plug in your RNG constructor here function prng_newstate() { return new Arcfour(); } // Pool size must be a multiple of 4 and greater than 32. // An array of bytes the size of the pool will be passed to init() var rng_psize = 256; // Random number generator - requires a PRNG backend, e.g. prng4.js // For best results, put code like // // in your main HTML document. var rng_state; var rng_pool; var rng_pptr; // Mix in a 32-bit integer into the pool function rng_seed_int(x) { rng_pool[rng_pptr++] ^= x & 255; rng_pool[rng_pptr++] ^= (x >> 8) & 255; rng_pool[rng_pptr++] ^= (x >> 16) & 255; rng_pool[rng_pptr++] ^= (x >> 24) & 255; if (rng_pptr >= rng_psize) rng_pptr -= rng_psize; } // Mix in the current time (w/milliseconds) into the pool function rng_seed_time() { rng_seed_int(new Date().getTime()); } // Initialize the pool with junk if needed. if (rng_pool == null) { rng_pool = new Array(); rng_pptr = 0; var t; if (navigator.appName == "Netscape" && navigator.appVersion < "5" && window.crypto) { // Extract entropy (256 bits) from NS4 RNG if available var z = window.crypto.random(32); for (t = 0; t < z.length; ++t) rng_pool[rng_pptr++] = z.charCodeAt(t) & 255; } while (rng_pptr < rng_psize) { // extract some randomness from Math.random() t = Math.floor(65536 * Math.random()); rng_pool[rng_pptr++] = t >>> 8; rng_pool[rng_pptr++] = t & 255; } rng_pptr = 0; rng_seed_time(); // rng_seed_int(window.screenX); // rng_seed_int(window.screenY); } function rng_get_byte() { if (rng_state == null) { rng_seed_time(); rng_state = prng_newstate(); rng_state.init(rng_pool); for (rng_pptr = 0; rng_pptr < rng_pool.length; ++rng_pptr) rng_pool[rng_pptr] = 0; rng_pptr = 0; // rng_pool = null; } // TODO: allow reseeding after first request return rng_state.next(); } function rng_get_bytes(ba) { var i; for (i = 0; i < ba.length; ++i) ba[i] = rng_get_byte(); } function SecureRandom() { } SecureRandom.prototype.nextBytes = rng_get_bytes; // Depends on jsbn.js and rng.js // convert a (hex) string to a bignum object function parseBigInt(str, r) { return new BigInteger(str, r); } function linebrk(s, n) { var ret = ""; var i = 0; while (i + n < s.length) { ret += s.substring(i, i + n) + "\n"; i += n; } return ret + s.substring(i, s.length); } function byte2Hex(b) { if (b < 0x10) return "0" + b.toString(16); else return b.toString(16); } // PKCS#1 (type 2, random) pad input string s to n bytes, and return a bigint function pkcs1pad2(s, n) { if (n < s.length + 11) { alert("Message too long for RSA"); return null; } var ba = new Array(); var i = s.length - 1; while (i >= 0 && n > 0) ba[--n] = s.charCodeAt(i--); ba[--n] = 0; var rng = new SecureRandom(); var x = new Array(); while (n > 2) { // random non-zero pad x[0] = 0; while (x[0] == 0) rng.nextBytes(x); ba[--n] = x[0]; } ba[--n] = 2; ba[--n] = 0; return new BigInteger(ba); } // "empty" RSA key constructor function RSAKey() { this.n = null; this.e = 0; this.d = null; this.p = null; this.q = null; this.dmp1 = null; this.dmq1 = null; this.coeff = null; } // Set the public key fields N and e from hex strings function RSASetPublic(N, E) { if (N != null && E != null && N.length > 0 && E.length > 0) { this.n = parseBigInt(N, 16); this.e = parseInt(E, 16); } else alert("Invalid RSA public key"); } // Perform raw public operation on "x": return x^e (mod n) function RSADoPublic(x) { return x.modPowInt(this.e, this.n); } // Return the PKCS#1 RSA encryption of "text" as an even-length hex string function RSAEncrypt(text) { var m = pkcs1pad2(text, (this.n.bitLength() + 7) >> 3); if (m == null) return null; var c = this.doPublic(m); if (c == null) return null; var h = c.toString(16); if ((h.length & 1) == 0) return h; else return "0" + h; } // Return the PKCS#1 RSA encryption of "text" as a Base64-encoded string // function RSAEncryptB64(text) { // var h = this.encrypt(text); // if(h) return hex2b64(h); else return null; // } // protected RSAKey.prototype.doPublic = RSADoPublic; // public RSAKey.prototype.setPublic = RSASetPublic; RSAKey.prototype.encrypt = RSAEncrypt; // RSAKey.prototype.encrypt_b64 = RSAEncryptB64; var b64map = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"; var b64pad = "="; function hex2b64(h) { var i; var c; var ret = ""; for (i = 0; i + 3 <= h.length; i += 3) { c = parseInt(h.substring(i, i + 3), 16); ret += b64map.charAt(c >> 6) + b64map.charAt(c & 63); } if (i + 1 == h.length) { c = parseInt(h.substring(i, i + 1), 16); ret += b64map.charAt(c << 2); } else if (i + 2 == h.length) { c = parseInt(h.substring(i, i + 2), 16); ret += b64map.charAt(c >> 2) + b64map.charAt((c & 3) << 4); } while ((ret.length & 3) > 0) ret += b64pad; return ret; } // convert a base64 string to hex function b64tohex(s) { var ret = "" var i; var k = 0; // b64 state, 0-3 var slop; for (i = 0; i < s.length; ++i) { if (s.charAt(i) == b64pad) break; v = b64map.indexOf(s.charAt(i)); if (v < 0) continue; if (k == 0) { ret += int2char(v >> 2); slop = v & 3; k = 1; } else if (k == 1) { ret += int2char((slop << 2) | (v >> 4)); slop = v & 0xf; k = 2; } else if (k == 2) { ret += int2char(slop); ret += int2char(v >> 2); slop = v & 3; k = 3; } else { ret += int2char((slop << 2) | (v >> 4)); ret += int2char(v & 0xf); k = 0; } } if (k == 1) ret += int2char(slop << 2); return ret; } // convert a base64 string to a byte/number array function b64toBA(s) { //piggyback on b64tohex for now, optimize later var h = b64tohex(s); var i; var a = new Array(); for (i = 0; 2 * i < h.length; ++i) { a[i] = parseInt(h.substring(2 * i, 2 * i + 2), 16); } return a; }