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Diffstat (limited to 'lib/jsbn.js')
-rw-r--r-- | lib/jsbn.js | 586 |
1 files changed, 586 insertions, 0 deletions
diff --git a/lib/jsbn.js b/lib/jsbn.js new file mode 100644 index 0000000..f557d12 --- /dev/null +++ b/lib/jsbn.js @@ -0,0 +1,586 @@ +/* + * Copyright (c) 2003-2005 Tom Wu + * All Rights Reserved. + * + * Permission is hereby granted, free of charge, to any person obtaining + * a copy of this software and associated documentation files (the + * "Software"), to deal in the Software without restriction, including + * without limitation the rights to use, copy, modify, merge, publish, + * distribute, sublicense, and/or sell copies of the Software, and to + * permit persons to whom the Software is furnished to do so, subject to + * the following conditions: + * + * The above copyright notice and this permission notice shall be + * included in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS-IS" AND WITHOUT WARRANTY OF ANY KIND, + * EXPRESS, IMPLIED OR OTHERWISE, INCLUDING WITHOUT LIMITATION, ANY + * WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. + * + * IN NO EVENT SHALL TOM WU BE LIABLE FOR ANY SPECIAL, INCIDENTAL, + * INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY KIND, OR ANY DAMAGES WHATSOEVER + * RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER OR NOT ADVISED OF + * THE POSSIBILITY OF DAMAGE, AND ON ANY THEORY OF LIABILITY, ARISING OUT + * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. + * + * In addition, the following condition applies: + * + * All redistributions must retain an intact copy of this copyright notice + * and disclaimer. + */ + +// 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); |