JS逆向案例2：咪咕视频——学会模块改写

案例网址：https://www.migu.cn/video.html
我们省略js逆向时定位的过程，直接看RSA加密部分的代码：

define("lib/rsa/rsa", [], function(a, b, c) {
    function d(a, b, c) {
        null != a && ("number" == typeof a ? this.fromNumber(a, b, c) : null == b && "string" != typeof a ? this.fromString(a, 256) : this.fromString(a, b))
    }
    function e() {
        return new d(null)
    }
    function f(a, b, c, d, e, f) {
        for (; --f >= 0; ) {
            var g = b * this[a++] + c[d] + e;
            e = Math.floor(g / 67108864),
            c[d++] = 67108863 & g
        }
        return e
    }
    function g(a, b, c, d, e, f) {
        for (var g = 32767 & b, h = b >> 15; --f >= 0; ) {
            var i = 32767 & this[a]
              , j = this[a++] >> 15
              , k = h * i + j * g;
            i = g * i + ((32767 & k) << 15) + c[d] + (1073741823 & e),
            e = (i >>> 30) + (k >>> 15) + h * j + (e >>> 30),
            c[d++] = 1073741823 & i
        }
        return e
    }
    function h(a, b, c, d, e, f) {
        for (var g = 16383 & b, h = b >> 14; --f >= 0; ) {
            var i = 16383 & this[a]
              , j = this[a++] >> 14
              , k = h * i + j * g;
            i = g * i + ((16383 & k) << 14) + c[d] + e,
            e = (i >> 28) + (k >> 14) + h * j,
            c[d++] = 268435455 & i
        }
        return e
    }
    function i(a) {
        return nb.charAt(a)
    }
    function j(a, b) {
        var c = ob[a.charCodeAt(b)];
        return null == c ? -1 : c
    }
    function k(a) {
        for (var b = this.t - 1; b >= 0; --b)
            a[b] = this[b];
        a.t = this.t,
        a.s = this.s
    }
    function l(a) {
        this.t = 1,
        this.s = 0 > a ? -1 : 0,
        a > 0 ? this[0] = a : -1 > a ? this[0] = a + this.DV : this.t = 0
    }
    function m(a) {
        var b = e();
        return b.fromInt(a),
        b
    }
    function n(a, b) {
        var c;
        if (16 == b)
            c = 4;
        else if (8 == b)
            c = 3;
        else if (256 == b)
            c = 8;
        else if (2 == b)
            c = 1;
        else if (32 == b)
            c = 5;
        else {
            if (4 != b)
                return void this.fromRadix(a, b);
            c = 2
        }
        this.t = 0,
        this.s = 0;
        for (var e = a.length, f = !1, g = 0; --e >= 0; ) {
            var h = 8 == c ? 255 & a[e] : j(a, e);
            0 > h ? "-" == a.charAt(e) && (f = !0) : (f = !1,
            0 == g ? this[this.t++] = h : g + c > this.DB ? (this[this.t - 1] |= (h & (1 << this.DB - g) - 1) << g,
            this[this.t++] = h >> this.DB - g) : this[this.t - 1] |= h << g,
            g += c,
            g >= this.DB && (g -= this.DB))
        }
        8 == c && 0 != (128 & a[0]) && (this.s = -1,
        g > 0 && (this[this.t - 1] |= (1 << this.DB - g) - 1 << g)),
        this.clamp(),
        f && d.ZERO.subTo(this, this)
    }
    function o() {
        for (var a = this.s & this.DM; this.t > 0 && this[this.t - 1] == a; )
            --this.t
    }
    function p(a) {
        if (this.s < 0)
            return "-" + this.negate().toString(a);
        var b;
        if (16 == a)
            b = 4;
        else if (8 == a)
            b = 3;
        else if (2 == a)
            b = 1;
        else if (32 == a)
            b = 5;
        else {
            if (4 != a)
                return this.toRadix(a);
            b = 2
        }
        var c, d = (1 << b) - 1, e = !1, f = "", g = this.t, h = this.DB - g * this.DB % b;
        if (g-- > 0)
            for (h < this.DB && (c = this[g] >> h) > 0 && (e = !0,
            f = i(c)); g >= 0; )
                b > h ? (c = (this[g] & (1 << h) - 1) << b - h,
                c |= this[--g] >> (h += this.DB - b)) : (c = this[g] >> (h -= b) & d,
                0 >= h && (h += this.DB,
                --g)),
                c > 0 && (e = !0),
                e && (f += i(c));
        return e ? f : "0"
    }
    function q() {
        var a = e();
        return d.ZERO.subTo(this, a),
        a
    }
    function r() {
        return this.s < 0 ? this.negate() : this
    }
    function s(a) {
        var b = this.s - a.s;
        if (0 != b)
            return b;
        var c = this.t;
        if (b = c - a.t,
        0 != b)
            return this.s < 0 ? -b : b;
        for (; --c >= 0; )
            if (0 != (b = this[c] - a[c]))
                return b;
        return 0
    }
    function t(a) {
        var b, c = 1;
        return 0 != (b = a >>> 16) && (a = b,
        c += 16),
        0 != (b = a >> 8) && (a = b,
        c += 8),
        0 != (b = a >> 4) && (a = b,
        c += 4),
        0 != (b = a >> 2) && (a = b,
        c += 2),
        0 != (b = a >> 1) && (a = b,
        c += 1),
        c
    }
    function u() {
        return this.t <= 0 ? 0 : this.DB * (this.t - 1) + t(this[this.t - 1] ^ this.s & this.DM)
    }
    function v(a, b) {
        var c;
        for (c = this.t - 1; c >= 0; --c)
            b[c + a] = this[c];
        for (c = a - 1; c >= 0; --c)
            b[c] = 0;
        b.t = this.t + a,
        b.s = this.s
    }
    function w(a, b) {
        for (var c = a; c < this.t; ++c)
            b[c - a] = this[c];
        b.t = Math.max(this.t - a, 0),
        b.s = this.s
    }
    function x(a, b) {
        var c, d = a % this.DB, e = this.DB - d, f = (1 << e) - 1, g = Math.floor(a / this.DB), h = this.s << d & this.DM;
        for (c = this.t - 1; c >= 0; --c)
            b[c + g + 1] = this[c] >> e | h,
            h = (this[c] & f) << d;
        for (c = g - 1; c >= 0; --c)
            b[c] = 0;
        b[g] = h,
        b.t = this.t + g + 1,
        b.s = this.s,
        b.clamp()
    }
    function y(a, b) {
        b.s = this.s;
        var c = Math.floor(a / this.DB);
        if (c >= this.t)
            return void (b.t = 0);
        var d = a % this.DB
          , e = this.DB - d
          , f = (1 << d) - 1;
        b[0] = this[c] >> d;
        for (var g = c + 1; g < this.t; ++g)
            b[g - c - 1] |= (this[g] & f) << e,
            b[g - c] = this[g] >> d;
        d > 0 && (b[this.t - c - 1] |= (this.s & f) << e),
        b.t = this.t - c,
        b.clamp()
    }
    function z(a, b) {
        for (var c = 0, d = 0, e = Math.min(a.t, this.t); e > c; )
            d += this[c] - a[c],
            b[c++] = d & this.DM,
            d >>= this.DB;
        if (a.t < this.t) {
            for (d -= a.s; c < this.t; )
                d += this[c],
                b[c++] = d & this.DM,
                d >>= this.DB;
            d += this.s
        } else {
            for (d += this.s; c < a.t; )
                d -= a[c],
                b[c++] = d & this.DM,
                d >>= this.DB;
            d -= a.s
        }
        b.s = 0 > d ? -1 : 0,
        -1 > d ? b[c++] = this.DV + d : d > 0 && (b[c++] = d),
        b.t = c,
        b.clamp()
    }
    function A(a, b) {
        var c = this.abs()
          , e = a.abs()
          , f = c.t;
        for (b.t = f + e.t; --f >= 0; )
            b[f] = 0;
        for (f = 0; f < e.t; ++f)
            b[f + c.t] = c.am(0, e[f], b, f, 0, c.t);
        b.s = 0,
        b.clamp(),
        this.s != a.s && d.ZERO.subTo(b, b)
    }
    function B(a) {
        for (var b = this.abs(), c = a.t = 2 * b.t; --c >= 0; )
            a[c] = 0;
        for (c = 0; c < b.t - 1; ++c) {
            var d = b.am(c, b[c], a, 2 * c, 0, 1);
            (a[c + b.t] += b.am(c + 1, 2 * b[c], a, 2 * c + 1, d, b.t - c - 1)) >= b.DV && (a[c + b.t] -= b.DV,
            a[c + b.t + 1] = 1)
        }
        a.t > 0 && (a[a.t - 1] += b.am(c, b[c], a, 2 * c, 0, 1)),
        a.s = 0,
        a.clamp()
    }
    function C(a, b, c) {
        var f = a.abs();
        if (!(f.t <= 0)) {
            var g = this.abs();
            if (g.t < f.t)
                return null != b && b.fromInt(0),
                void (null != c && this.copyTo(c));
            null == c && (c = e());
            var h = e()
              , i = this.s
              , j = a.s
              , k = this.DB - t(f[f.t - 1]);
            k > 0 ? (f.lShiftTo(k, h),
            g.lShiftTo(k, c)) : (f.copyTo(h),
            g.copyTo(c));
            var l = h.t
              , m = h[l - 1];
            if (0 != m) {
                var n = m * (1 << this.F1) + (l > 1 ? h[l - 2] >> this.F2 : 0)
                  , o = this.FV / n
                  , p = (1 << this.F1) / n
                  , q = 1 << this.F2
                  , r = c.t
                  , s = r - l
                  , u = null == b ? e() : b;
                for (h.dlShiftTo(s, u),
                c.compareTo(u) >= 0 && (c[c.t++] = 1,
                c.subTo(u, c)),
                d.ONE.dlShiftTo(l, u),
                u.subTo(h, h); h.t < l; )
                    h[h.t++] = 0;
                for (; --s >= 0; ) {
                    var v = c[--r] == m ? this.DM : Math.floor(c[r] * o + (c[r - 1] + q) * p);
                    if ((c[r] += h.am(0, v, c, s, 0, l)) < v)
                        for (h.dlShiftTo(s, u),
                        c.subTo(u, c); c[r] < --v; )
                            c.subTo(u, c)
                }
                null != b && (c.drShiftTo(l, b),
                i != j && d.ZERO.subTo(b, b)),
                c.t = l,
                c.clamp(),
                k > 0 && c.rShiftTo(k, c),
                0 > i && d.ZERO.subTo(c, c)
            }
        }
    }
    function D(a) {
        var b = e();
        return this.abs().divRemTo(a, null, b),
        this.s < 0 && b.compareTo(d.ZERO) > 0 && a.subTo(b, b),
        b
    }
    function E(a) {
        this.m = a
    }
    function F(a) {
        return a.s < 0 || a.compareTo(this.m) >= 0 ? a.mod(this.m) : a
    }
    function G(a) {
        return a
    }
    function H(a) {
        a.divRemTo(this.m, null, a)
    }
    function I(a, b, c) {
        a.multiplyTo(b, c),
        this.reduce(c)
    }
    function J(a, b) {
        a.squareTo(b),
        this.reduce(b)
    }
    function K() {
        if (this.t < 1)
            return 0;
        var a = this[0];
        if (0 == (1 & a))
            return 0;
        var b = 3 & a;
        return b = b * (2 - (15 & a) * b) & 15,
        b = b * (2 - (255 & a) * b) & 255,
        b = b * (2 - ((65535 & a) * b & 65535)) & 65535,
        b = b * (2 - a * b % this.DV) % this.DV,
        b > 0 ? this.DV - b : -b
    }
    function L(a) {
        this.m = a,
        this.mp = a.invDigit(),
        this.mpl = 32767 & this.mp,
        this.mph = this.mp >> 15,
        this.um = (1 << a.DB - 15) - 1,
        this.mt2 = 2 * a.t
    }
    function M(a) {
        var b = e();
        return a.abs().dlShiftTo(this.m.t, b),
        b.divRemTo(this.m, null, b),
        a.s < 0 && b.compareTo(d.ZERO) > 0 && this.m.subTo(b, b),
        b
    }
    function N(a) {
        var b = e();
        return a.copyTo(b),
        this.reduce(b),
        b
    }
    function O(a) {
        for (; a.t <= this.mt2; )
            a[a.t++] = 0;
        for (var b = 0; b < this.m.t; ++b) {
            var c = 32767 & a[b]
              , d = c * this.mpl + ((c * this.mph + (a[b] >> 15) * this.mpl & this.um) << 15) & a.DM;
            for (c = b + this.m.t,
            a[c] += this.m.am(0, d, a, b, 0, this.m.t); a[c] >= a.DV; )
                a[c] -= a.DV,
                a[++c]++
        }
        a.clamp(),
        a.drShiftTo(this.m.t, a),
        a.compareTo(this.m) >= 0 && a.subTo(this.m, a)
    }
    function P(a, b) {
        a.squareTo(b),
        this.reduce(b)
    }
    function Q(a, b, c) {
        a.multiplyTo(b, c),
        this.reduce(c)
    }
    function R() {
        return 0 == (this.t > 0 ? 1 & this[0] : this.s)
    }
    function S(a, b) {
        if (a > 4294967295 || 1 > a)
            return d.ONE;
        var c = e()
          , f = e()
          , g = b.convert(this)
          , h = t(a) - 1;
        for (g.copyTo(c); --h >= 0; )
            if (b.sqrTo(c, f),
            (a & 1 << h) > 0)
                b.mulTo(f, g, c);
            else {
                var i = c;
                c = f,
                f = i
            }
        return b.revert(c)
    }
    function T(a, b) {
        var c;
        return c = 256 > a || b.isEven() ? new E(b) : new L(b),
        this.exp(a, c)
    }
    function U() {
        this.i = 0,
        this.j = 0,
        this.S = new Array
    }
    function V(a) {
        var b, c, d;
        for (b = 0; 256 > b; ++b)
            this.S[b] = b;
        for (c = 0,
        b = 0; 256 > b; ++b)
            c = c + this.S[b] + a[b % a.length] & 255,
            d = this.S[b],
            this.S[b] = this.S[c],
            this.S[c] = d;
        this.i = 0,
        this.j = 0
    }
    function W() {
        var a;
        return this.i = this.i + 1 & 255,
        this.j = this.j + this.S[this.i] & 255,
        a = this.S[this.i],
        this.S[this.i] = this.S[this.j],
        this.S[this.j] = a,
        this.S[a + this.S[this.i] & 255]
    }
    function X() {
        return new U
    }
    function Y(a) {
        qb[rb++] ^= 255 & a,
        qb[rb++] ^= a >> 8 & 255,
        qb[rb++] ^= a >> 16 & 255,
        qb[rb++] ^= a >> 24 & 255,
        rb >= sb && (rb -= sb)
    }
    function Z() {
        Y((new Date).getTime())
    }
    function $() {
        if (null == pb) {
            for (Z(),
            pb = X(),
            pb.init(qb),
            rb = 0; rb < qb.length; ++rb)
                qb[rb] = 0;
            rb = 0
        }
        return pb.next()
    }
    function _(a) {
        var b;
        for (b = 0; b < a.length; ++b)
            a[b] = $()
    }
    function ab() {}
    function bb(a, b) {
        return new d(a,b)
    }
    function cb(a, b) {
        if (b < a.length + 11)
            return alert("Message too long for RSA"),
            null;
        for (var c = new Array, e = a.length - 1; e >= 0 && b > 0; ) {
            var f = a.charCodeAt(e--);
            128 > f ? c[--b] = f : f > 127 && 2048 > f ? (c[--b] = 63 & f | 128,
            c[--b] = f >> 6 | 192) : (c[--b] = 63 & f | 128,
            c[--b] = f >> 6 & 63 | 128,
            c[--b] = f >> 12 | 224)
        }
        c[--b] = 0;
        for (var g = new ab, h = new Array; b > 2; ) {
            for (h[0] = 0; 0 == h[0]; )
                g.nextBytes(h);
            c[--b] = h[0]
        }
        return c[--b] = 2,
        c[--b] = 0,
        new d(c)
    }
    function db() {
        this.n = null,
        this.e = 0,
        this.d = null,
        this.p = null,
        this.q = null,
        this.dmp1 = null,
        this.dmq1 = null,
        this.coeff = null
    }
    function eb(a, b) {
        null != a && null != b && a.length > 0 && b.length > 0 ? (this.n = bb(a, 16),
        this.e = parseInt(b, 16)) : alert("网络异常，请点击登录重试")
    }
    function fb(a) {
        return a.modPowInt(this.e, this.n)
    }
    function gb(a) {
        var b = cb(a, this.n.bitLength() + 7 >> 3);
        if (null == b)
            return null;
        var c = this.doPublic(b);
        if (null == c)
            return null;
        var d = c.toString(16);
        return 0 == (1 & d.length) ? d : "0" + d
    }
    var hb, ib = 0xdeadbeefcafe, jb = 15715070 == (16777215 & ib);
    jb && "Microsoft Internet Explorer" == navigator.appName ? (d.prototype.am = g,
    hb = 30) : jb && "Netscape" != navigator.appName ? (d.prototype.am = f,
    hb = 26) : (d.prototype.am = h,
    hb = 28),
    d.prototype.DB = hb,
    d.prototype.DM = (1 << hb) - 1,
    d.prototype.DV = 1 << hb;
    var kb = 52;
    d.prototype.FV = Math.pow(2, kb),
    d.prototype.F1 = kb - hb,
    d.prototype.F2 = 2 * hb - kb;
    var lb, mb, nb = "0123456789abcdefghijklmnopqrstuvwxyz", ob = new Array;
    for (lb = "0".charCodeAt(0),
    mb = 0; 9 >= mb; ++mb)
        ob[lb++] = mb;
    for (lb = "a".charCodeAt(0),
    mb = 10; 36 > mb; ++mb)
        ob[lb++] = mb;
    for (lb = "A".charCodeAt(0),
    mb = 10; 36 > mb; ++mb)
        ob[lb++] = mb;
    E.prototype.convert = F,
    E.prototype.revert = G,
    E.prototype.reduce = H,
    E.prototype.mulTo = I,
    E.prototype.sqrTo = J,
    L.prototype.convert = M,
    L.prototype.revert = N,
    L.prototype.reduce = O,
    L.prototype.mulTo = Q,
    L.prototype.sqrTo = P,
    d.prototype.copyTo = k,
    d.prototype.fromInt = l,
    d.prototype.fromString = n,
    d.prototype.clamp = o,
    d.prototype.dlShiftTo = v,
    d.prototype.drShiftTo = w,
    d.prototype.lShiftTo = x,
    d.prototype.rShiftTo = y,
    d.prototype.subTo = z,
    d.prototype.multiplyTo = A,
    d.prototype.squareTo = B,
    d.prototype.divRemTo = C,
    d.prototype.invDigit = K,
    d.prototype.isEven = R,
    d.prototype.exp = S,
    d.prototype.toString = p,
    d.prototype.negate = q,
    d.prototype.abs = r,
    d.prototype.compareTo = s,
    d.prototype.bitLength = u,
    d.prototype.mod = D,
    d.prototype.modPowInt = T,
    d.ZERO = m(0),
    d.ONE = m(1),
    U.prototype.init = V,
    U.prototype.next = W;
    var pb, qb, rb, sb = 256;
    if (null == qb) {
        qb = new Array,
        rb = 0;
        var tb;
        if (window.crypto && window.crypto.getRandomValues) {
            var ub = new Uint8Array(32);
            for (window.crypto.getRandomValues(ub),
            tb = 0; 32 > tb; ++tb)
                qb[rb++] = ub[tb]
        }
        if ("Netscape" == navigator.appName && navigator.appVersion < "5" && window.crypto) {
            var vb = window.crypto.random(32);
            for (tb = 0; tb < vb.length; ++tb)
                qb[rb++] = 255 & vb.charCodeAt(tb)
        }
        for (; sb > rb; )
            tb = Math.floor(65536 * Math.random()),
            qb[rb++] = tb >>> 8,
            qb[rb++] = 255 & tb;
        rb = 0,
        Z()
    }
    ab.prototype.nextBytes = _,
    db.prototype.doPublic = fb,
    db.prototype.setPublic = eb,
    db.prototype.encrypt = gb,
    c.exports = {
        RSAKey: db
    }
}),

和案例1如出一辙，也是一个模块 不过不同的是，在调用RSAKey的时候，不是一个函数，而是一个构造函数，我们酱紫进行改造：
1.去掉首尾大括号，暴露内部函数
2.去掉export及其里面的部分
3.不调用RSAKey，而是调用db
改造好的代码如下：

    function d(a, b, c) {
        null != a && ("number" == typeof a ? this.fromNumber(a, b, c) : null == b && "string" != typeof a ? this.fromString(a, 256) : this.fromString(a, b))
    }
    function e() {
        return new d(null)
    }
    function f(a, b, c, d, e, f) {
        for (; --f >= 0; ) {
            var g = b * this[a++] + c[d] + e;
            e = Math.floor(g / 67108864),
            c[d++] = 67108863 & g
        }
        return e
    }
    function g(a, b, c, d, e, f) {
        for (var g = 32767 & b, h = b >> 15; --f >= 0; ) {
            var i = 32767 & this[a]
              , j = this[a++] >> 15
              , k = h * i + j * g;
            i = g * i + ((32767 & k) << 15) + c[d] + (1073741823 & e),
            e = (i >>> 30) + (k >>> 15) + h * j + (e >>> 30),
            c[d++] = 1073741823 & i
        }
        return e
    }
    function h(a, b, c, d, e, f) {
        for (var g = 16383 & b, h = b >> 14; --f >= 0; ) {
            var i = 16383 & this[a]
              , j = this[a++] >> 14
              , k = h * i + j * g;
            i = g * i + ((16383 & k) << 14) + c[d] + e,
            e = (i >> 28) + (k >> 14) + h * j,
            c[d++] = 268435455 & i
        }
        return e
    }
    function i(a) {
        return nb.charAt(a)
    }
    function j(a, b) {
        var c = ob[a.charCodeAt(b)];
        return null == c ? -1 : c
    }
    function k(a) {
        for (var b = this.t - 1; b >= 0; --b)
            a[b] = this[b];
        a.t = this.t,
        a.s = this.s
    }
    function l(a) {
        this.t = 1,
        this.s = 0 > a ? -1 : 0,
        a > 0 ? this[0] = a : -1 > a ? this[0] = a + this.DV : this.t = 0
    }
    function m(a) {
        var b = e();
        return b.fromInt(a),
        b
    }
    function n(a, b) {
        var c;
        if (16 == b)
            c = 4;
        else if (8 == b)
            c = 3;
        else if (256 == b)
            c = 8;
        else if (2 == b)
            c = 1;
        else if (32 == b)
            c = 5;
        else {
            if (4 != b)
                return void this.fromRadix(a, b);
            c = 2
        }
        this.t = 0,
        this.s = 0;
        for (var e = a.length, f = !1, g = 0; --e >= 0; ) {
            var h = 8 == c ? 255 & a[e] : j(a, e);
            0 > h ? "-" == a.charAt(e) && (f = !0) : (f = !1,
            0 == g ? this[this.t++] = h : g + c > this.DB ? (this[this.t - 1] |= (h & (1 << this.DB - g) - 1) << g,
            this[this.t++] = h >> this.DB - g) : this[this.t - 1] |= h << g,
            g += c,
            g >= this.DB && (g -= this.DB))
        }
        8 == c && 0 != (128 & a[0]) && (this.s = -1,
        g > 0 && (this[this.t - 1] |= (1 << this.DB - g) - 1 << g)),
        this.clamp(),
        f && d.ZERO.subTo(this, this)
    }
    function o() {
        for (var a = this.s & this.DM; this.t > 0 && this[this.t - 1] == a; )
            --this.t
    }
    function p(a) {
        if (this.s < 0)
            return "-" + this.negate().toString(a);
        var b;
        if (16 == a)
            b = 4;
        else if (8 == a)
            b = 3;
        else if (2 == a)
            b = 1;
        else if (32 == a)
            b = 5;
        else {
            if (4 != a)
                return this.toRadix(a);
            b = 2
        }
        var c, d = (1 << b) - 1, e = !1, f = "", g = this.t, h = this.DB - g * this.DB % b;
        if (g-- > 0)
            for (h < this.DB && (c = this[g] >> h) > 0 && (e = !0,
            f = i(c)); g >= 0; )
                b > h ? (c = (this[g] & (1 << h) - 1) << b - h,
                c |= this[--g] >> (h += this.DB - b)) : (c = this[g] >> (h -= b) & d,
                0 >= h && (h += this.DB,
                --g)),
                c > 0 && (e = !0),
                e && (f += i(c));
        return e ? f : "0"
    }
    function q() {
        var a = e();
        return d.ZERO.subTo(this, a),
        a
    }
    function r() {
        return this.s < 0 ? this.negate() : this
    }
    function s(a) {
        var b = this.s - a.s;
        if (0 != b)
            return b;
        var c = this.t;
        if (b = c - a.t,
        0 != b)
            return this.s < 0 ? -b : b;
        for (; --c >= 0; )
            if (0 != (b = this[c] - a[c]))
                return b;
        return 0
    }
    function t(a) {
        var b, c = 1;
        return 0 != (b = a >>> 16) && (a = b,
        c += 16),
        0 != (b = a >> 8) && (a = b,
        c += 8),
        0 != (b = a >> 4) && (a = b,
        c += 4),
        0 != (b = a >> 2) && (a = b,
        c += 2),
        0 != (b = a >> 1) && (a = b,
        c += 1),
        c
    }
    function u() {
        return this.t <= 0 ? 0 : this.DB * (this.t - 1) + t(this[this.t - 1] ^ this.s & this.DM)
    }
    function v(a, b) {
        var c;
        for (c = this.t - 1; c >= 0; --c)
            b[c + a] = this[c];
        for (c = a - 1; c >= 0; --c)
            b[c] = 0;
        b.t = this.t + a,
        b.s = this.s
    }
    function w(a, b) {
        for (var c = a; c < this.t; ++c)
            b[c - a] = this[c];
        b.t = Math.max(this.t - a, 0),
        b.s = this.s
    }
    function x(a, b) {
        var c, d = a % this.DB, e = this.DB - d, f = (1 << e) - 1, g = Math.floor(a / this.DB), h = this.s << d & this.DM;
        for (c = this.t - 1; c >= 0; --c)
            b[c + g + 1] = this[c] >> e | h,
            h = (this[c] & f) << d;
        for (c = g - 1; c >= 0; --c)
            b[c] = 0;
        b[g] = h,
        b.t = this.t + g + 1,
        b.s = this.s,
        b.clamp()
    }
    function y(a, b) {
        b.s = this.s;
        var c = Math.floor(a / this.DB);
        if (c >= this.t)
            return void (b.t = 0);
        var d = a % this.DB
          , e = this.DB - d
          , f = (1 << d) - 1;
        b[0] = this[c] >> d;
        for (var g = c + 1; g < this.t; ++g)
            b[g - c - 1] |= (this[g] & f) << e,
            b[g - c] = this[g] >> d;
        d > 0 && (b[this.t - c - 1] |= (this.s & f) << e),
        b.t = this.t - c,
        b.clamp()
    }
    function z(a, b) {
        for (var c = 0, d = 0, e = Math.min(a.t, this.t); e > c; )
            d += this[c] - a[c],
            b[c++] = d & this.DM,
            d >>= this.DB;
        if (a.t < this.t) {
            for (d -= a.s; c < this.t; )
                d += this[c],
                b[c++] = d & this.DM,
                d >>= this.DB;
            d += this.s
        } else {
            for (d += this.s; c < a.t; )
                d -= a[c],
                b[c++] = d & this.DM,
                d >>= this.DB;
            d -= a.s
        }
        b.s = 0 > d ? -1 : 0,
        -1 > d ? b[c++] = this.DV + d : d > 0 && (b[c++] = d),
        b.t = c,
        b.clamp()
    }
    function A(a, b) {
        var c = this.abs()
          , e = a.abs()
          , f = c.t;
        for (b.t = f + e.t; --f >= 0; )
            b[f] = 0;
        for (f = 0; f < e.t; ++f)
            b[f + c.t] = c.am(0, e[f], b, f, 0, c.t);
        b.s = 0,
        b.clamp(),
        this.s != a.s && d.ZERO.subTo(b, b)
    }
    function B(a) {
        for (var b = this.abs(), c = a.t = 2 * b.t; --c >= 0; )
            a[c] = 0;
        for (c = 0; c < b.t - 1; ++c) {
            var d = b.am(c, b[c], a, 2 * c, 0, 1);
            (a[c + b.t] += b.am(c + 1, 2 * b[c], a, 2 * c + 1, d, b.t - c - 1)) >= b.DV && (a[c + b.t] -= b.DV,
            a[c + b.t + 1] = 1)
        }
        a.t > 0 && (a[a.t - 1] += b.am(c, b[c], a, 2 * c, 0, 1)),
        a.s = 0,
        a.clamp()
    }
    function C(a, b, c) {
        var f = a.abs();
        if (!(f.t <= 0)) {
            var g = this.abs();
            if (g.t < f.t)
                return null != b && b.fromInt(0),
                void (null != c && this.copyTo(c));
            null == c && (c = e());
            var h = e()
              , i = this.s
              , j = a.s
              , k = this.DB - t(f[f.t - 1]);
            k > 0 ? (f.lShiftTo(k, h),
            g.lShiftTo(k, c)) : (f.copyTo(h),
            g.copyTo(c));
            var l = h.t
              , m = h[l - 1];
            if (0 != m) {
                var n = m * (1 << this.F1) + (l > 1 ? h[l - 2] >> this.F2 : 0)
                  , o = this.FV / n
                  , p = (1 << this.F1) / n
                  , q = 1 << this.F2
                  , r = c.t
                  , s = r - l
                  , u = null == b ? e() : b;
                for (h.dlShiftTo(s, u),
                c.compareTo(u) >= 0 && (c[c.t++] = 1,
                c.subTo(u, c)),
                d.ONE.dlShiftTo(l, u),
                u.subTo(h, h); h.t < l; )
                    h[h.t++] = 0;
                for (; --s >= 0; ) {
                    var v = c[--r] == m ? this.DM : Math.floor(c[r] * o + (c[r - 1] + q) * p);
                    if ((c[r] += h.am(0, v, c, s, 0, l)) < v)
                        for (h.dlShiftTo(s, u),
                        c.subTo(u, c); c[r] < --v; )
                            c.subTo(u, c)
                }
                null != b && (c.drShiftTo(l, b),
                i != j && d.ZERO.subTo(b, b)),
                c.t = l,
                c.clamp(),
                k > 0 && c.rShiftTo(k, c),
                0 > i && d.ZERO.subTo(c, c)
            }
        }
    }
    function D(a) {
        var b = e();
        return this.abs().divRemTo(a, null, b),
        this.s < 0 && b.compareTo(d.ZERO) > 0 && a.subTo(b, b),
        b
    }
    function E(a) {
        this.m = a
    }
    function F(a) {
        return a.s < 0 || a.compareTo(this.m) >= 0 ? a.mod(this.m) : a
    }
    function G(a) {
        return a
    }
    function H(a) {
        a.divRemTo(this.m, null, a)
    }
    function I(a, b, c) {
        a.multiplyTo(b, c),
        this.reduce(c)
    }
    function J(a, b) {
        a.squareTo(b),
        this.reduce(b)
    }
    function K() {
        if (this.t < 1)
            return 0;
        var a = this[0];
        if (0 == (1 & a))
            return 0;
        var b = 3 & a;
        return b = b * (2 - (15 & a) * b) & 15,
        b = b * (2 - (255 & a) * b) & 255,
        b = b * (2 - ((65535 & a) * b & 65535)) & 65535,
        b = b * (2 - a * b % this.DV) % this.DV,
        b > 0 ? this.DV - b : -b
    }
    function L(a) {
        this.m = a,
        this.mp = a.invDigit(),
        this.mpl = 32767 & this.mp,
        this.mph = this.mp >> 15,
        this.um = (1 << a.DB - 15) - 1,
        this.mt2 = 2 * a.t
    }
    function M(a) {
        var b = e();
        return a.abs().dlShiftTo(this.m.t, b),
        b.divRemTo(this.m, null, b),
        a.s < 0 && b.compareTo(d.ZERO) > 0 && this.m.subTo(b, b),
        b
    }
    function N(a) {
        var b = e();
        return a.copyTo(b),
        this.reduce(b),
        b
    }
    function O(a) {
        for (; a.t <= this.mt2; )
            a[a.t++] = 0;
        for (var b = 0; b < this.m.t; ++b) {
            var c = 32767 & a[b]
              , d = c * this.mpl + ((c * this.mph + (a[b] >> 15) * this.mpl & this.um) << 15) & a.DM;
            for (c = b + this.m.t,
            a[c] += this.m.am(0, d, a, b, 0, this.m.t); a[c] >= a.DV; )
                a[c] -= a.DV,
                a[++c]++
        }
        a.clamp(),
        a.drShiftTo(this.m.t, a),
        a.compareTo(this.m) >= 0 && a.subTo(this.m, a)
    }
    function P(a, b) {
        a.squareTo(b),
        this.reduce(b)
    }
    function Q(a, b, c) {
        a.multiplyTo(b, c),
        this.reduce(c)
    }
    function R() {
        return 0 == (this.t > 0 ? 1 & this[0] : this.s)
    }
    function S(a, b) {
        if (a > 4294967295 || 1 > a)
            return d.ONE;
        var c = e()
          , f = e()
          , g = b.convert(this)
          , h = t(a) - 1;
        for (g.copyTo(c); --h >= 0; )
            if (b.sqrTo(c, f),
            (a & 1 << h) > 0)
                b.mulTo(f, g, c);
            else {
                var i = c;
                c = f,
                f = i
            }
        return b.revert(c)
    }
    function T(a, b) {
        var c;
        return c = 256 > a || b.isEven() ? new E(b) : new L(b),
        this.exp(a, c)
    }
    function U() {
        this.i = 0,
        this.j = 0,
        this.S = new Array
    }
    function V(a) {
        var b, c, d;
        for (b = 0; 256 > b; ++b)
            this.S[b] = b;
        for (c = 0,
        b = 0; 256 > b; ++b)
            c = c + this.S[b] + a[b % a.length] & 255,
            d = this.S[b],
            this.S[b] = this.S[c],
            this.S[c] = d;
        this.i = 0,
        this.j = 0
    }
    function W() {
        var a;
        return this.i = this.i + 1 & 255,
        this.j = this.j + this.S[this.i] & 255,
        a = this.S[this.i],
        this.S[this.i] = this.S[this.j],
        this.S[this.j] = a,
        this.S[a + this.S[this.i] & 255]
    }
    function X() {
        return new U
    }
    function Y(a) {
        qb[rb++] ^= 255 & a,
        qb[rb++] ^= a >> 8 & 255,
        qb[rb++] ^= a >> 16 & 255,
        qb[rb++] ^= a >> 24 & 255,
        rb >= sb && (rb -= sb)
    }
    function Z() {
        Y((new Date).getTime())
    }
    function $() {
        if (null == pb) {
            for (Z(),
            pb = X(),
            pb.init(qb),
            rb = 0; rb < qb.length; ++rb)
                qb[rb] = 0;
            rb = 0
        }
        return pb.next()
    }
    function _(a) {
        var b;
        for (b = 0; b < a.length; ++b)
            a[b] = $()
    }
    function ab() {}
    function bb(a, b) {
        return new d(a,b)
    }
    function cb(a, b) {
        if (b < a.length + 11)
            return alert("Message too long for RSA"),
            null;
        for (var c = new Array, e = a.length - 1; e >= 0 && b > 0; ) {
            var f = a.charCodeAt(e--);
            128 > f ? c[--b] = f : f > 127 && 2048 > f ? (c[--b] = 63 & f | 128,
            c[--b] = f >> 6 | 192) : (c[--b] = 63 & f | 128,
            c[--b] = f >> 6 & 63 | 128,
            c[--b] = f >> 12 | 224)
        }
        c[--b] = 0;
        for (var g = new ab, h = new Array; b > 2; ) {
            for (h[0] = 0; 0 == h[0]; )
                g.nextBytes(h);
            c[--b] = h[0]
        }
        return c[--b] = 2,
        c[--b] = 0,
        new d(c)
    }
    function db() {
        this.n = null,
        this.e = 0,
        this.d = null,
        this.p = null,
        this.q = null,
        this.dmp1 = null,
        this.dmq1 = null,
        this.coeff = null
    }
    function eb(a, b) {
        null != a && null != b && a.length > 0 && b.length > 0 ? (this.n = bb(a, 16),
        this.e = parseInt(b, 16)) : alert("网络异常，请点击登录重试")
    }
    function fb(a) {
        return a.modPowInt(this.e, this.n)
    }
    function gb(a) {
        var b = cb(a, this.n.bitLength() + 7 >> 3);
        if (null == b)
            return null;
        var c = this.doPublic(b);
        if (null == c)
            return null;
        var d = c.toString(16);
        return 0 == (1 & d.length) ? d : "0" + d
    }
    var hb, ib = 0xdeadbeefcafe, jb = 15715070 == (16777215 & ib);
    jb && "Microsoft Internet Explorer" == navigator.appName ? (d.prototype.am = g,
    hb = 30) : jb && "Netscape" != navigator.appName ? (d.prototype.am = f,
    hb = 26) : (d.prototype.am = h,
    hb = 28),
    d.prototype.DB = hb,
    d.prototype.DM = (1 << hb) - 1,
    d.prototype.DV = 1 << hb;
    var kb = 52;
    d.prototype.FV = Math.pow(2, kb),
    d.prototype.F1 = kb - hb,
    d.prototype.F2 = 2 * hb - kb;
    var lb, mb, nb = "0123456789abcdefghijklmnopqrstuvwxyz", ob = new Array;
    for (lb = "0".charCodeAt(0),
    mb = 0; 9 >= mb; ++mb)
        ob[lb++] = mb;
    for (lb = "a".charCodeAt(0),
    mb = 10; 36 > mb; ++mb)
        ob[lb++] = mb;
    for (lb = "A".charCodeAt(0),
    mb = 10; 36 > mb; ++mb)
        ob[lb++] = mb;
    E.prototype.convert = F,
    E.prototype.revert = G,
    E.prototype.reduce = H,
    E.prototype.mulTo = I,
    E.prototype.sqrTo = J,
    L.prototype.convert = M,
    L.prototype.revert = N,
    L.prototype.reduce = O,
    L.prototype.mulTo = Q,
    L.prototype.sqrTo = P,
    d.prototype.copyTo = k,
    d.prototype.fromInt = l,
    d.prototype.fromString = n,
    d.prototype.clamp = o,
    d.prototype.dlShiftTo = v,
    d.prototype.drShiftTo = w,
    d.prototype.lShiftTo = x,
    d.prototype.rShiftTo = y,
    d.prototype.subTo = z,
    d.prototype.multiplyTo = A,
    d.prototype.squareTo = B,
    d.prototype.divRemTo = C,
    d.prototype.invDigit = K,
    d.prototype.isEven = R,
    d.prototype.exp = S,
    d.prototype.toString = p,
    d.prototype.negate = q,
    d.prototype.abs = r,
    d.prototype.compareTo = s,
    d.prototype.bitLength = u,
    d.prototype.mod = D,
    d.prototype.modPowInt = T,
    d.ZERO = m(0),
    d.ONE = m(1),
    U.prototype.init = V,
    U.prototype.next = W;
    var pb, qb, rb, sb = 256;
    if (null == qb) {
        qb = new Array,
        rb = 0;
        var tb;
        if (window.crypto && window.crypto.getRandomValues) {
            var ub = new Uint8Array(32);
            for (window.crypto.getRandomValues(ub),
            tb = 0; 32 > tb; ++tb)
                qb[rb++] = ub[tb]
        }
        if ("Netscape" == navigator.appName && navigator.appVersion < "5" && window.crypto) {
            var vb = window.crypto.random(32);
            for (tb = 0; tb < vb.length; ++tb)
                qb[rb++] = 255 & vb.charCodeAt(tb)
        }
        for (; sb > rb; )
            tb = Math.floor(65536 * Math.random()),
            qb[rb++] = tb >>> 8,
            qb[rb++] = 255 & tb;
        rb = 0,
        Z()
    }
    ab.prototype.nextBytes = _,
    db.prototype.doPublic = fb,
    db.prototype.setPublic = eb,
    db.prototype.encrypt = gb

解决了改写的问题，还有浏览器DOM BOM（window navigator等）对象的改写问题，有想了解的朋友私聊我。