首页 > 技术文章 > python实现网页登录时的rsa加密流程

taurusfy 2017-06-23 17:49 原文

对某些网站的登录包进行抓包时发现,客户端对用户名进行了加密,然后传给服务器进行校验。

使用chrome调试功能断点调试,发现网站用javascript对用户名做了rsa加密。

为了实现网站的自动登录,需要模拟这个加密过程。

网上搜了下关于rsa加密的最简明的解释:

rsa加密是非对称加密算法,该算法基于一个十分简单的数论事实:将两个大素数相乘十分容易,但那时想要对其乘积进行因式分解却极其困难,因此可以将乘积公开作为加密密钥,即公钥,而两个大素数组合成私钥。公钥是可发布的供任何人使用,私钥则为自己所有,供解密之用。

断点调试:

经过分析,登录网站使用公钥对用户名进行加密,公钥值在登录页面响应报文中可以找到,一般为exponent和modulus。

其中exponent为指数,一般为65537,十六进制为010001。

modulus为加密算法中用到的n值,即大数乘积,一般rsa加密算法的介绍文章中都是:(N,e)为公钥,(N,d)为私钥

js代码中有详细的实现过程,比较复杂,如果看懂了再用python来实现,代价太高。

我尝试了三种解决方式:

1、将js代码扣出来,借用浏览器来执行

即使用python的webserver功能,在浏览器上实现js的计算,并将结果返回给客户端

使用python2.7 的BaseHTTPServer模块实现一个模拟加密的过程

server端代码:

#!/usr/bin/env python
# coding:utf-8
from BaseHTTPServer import HTTPServer,BaseHTTPRequestHandler
import io,shutil,urllib 
import urlparse 
class RequestHandler(BaseHTTPRequestHandler):
    #def do_Head(self):
        #self._writeheaders()
    def _writeheaders(self):
        self.send_response(200)
        self.send_header('Content-type', 'text/html')
        self.end_headers()
    def do_GET(self):  
        parsed_path = urlparse.urlparse(self.path);
        self._writeheaders()
        self.wfile.write("""<!doctype html>
<html class="no-js" lang="">
<head>
    <meta charset="utf-8">
    <title>RSATEST</title>
    <script>
         /*
         * RSA, a suite of routines for performing RSA public-key computations in JavaScript.
         * Copyright 1998-2005 David Shapiro.
         * Dave Shapiro
         * dave@ohdave.com 
         * changed by Fuchun, 2010-05-06
         * fcrpg2005@gmail.com
         */
        (function($w) {       
        if(typeof $w.RSAUtils === 'undefined')
            var RSAUtils = $w.RSAUtils = {};
        
        var biRadixBase = 2;
        var biRadixBits = 16;
        var bitsPerDigit = biRadixBits;
        var biRadix = 1 << 16; // = 2^16 = 65536
        var biHalfRadix = biRadix >>> 1;
        var biRadixSquared = biRadix * biRadix;
        var maxDigitVal = biRadix - 1;
        var maxInteger = 9999999999999998;
        
        //maxDigits:
        //Change this to accommodate your largest number size. Use setMaxDigits()
        //to change it!
        //
        //In general, if you're working with numbers of size N bits, you'll need 2*N
        //bits of storage. Each digit holds 16 bits. So, a 1024-bit key will need
        //
        //1024 * 2 / 16 = 128 digits of storage.
        //
        var maxDigits;
        var ZERO_ARRAY;
        var bigZero, bigOne;
        
        var BigInt = $w.BigInt = function(flag) {
            if (typeof flag == "boolean" && flag == true) {
                this.digits = null;
            } else {
                this.digits = ZERO_ARRAY.slice(0);
            }
            this.isNeg = false;
        };
        
        RSAUtils.setMaxDigits = function(value) {
            maxDigits = value;
            ZERO_ARRAY = new Array(maxDigits);
            for (var iza = 0; iza < ZERO_ARRAY.length; iza++) ZERO_ARRAY[iza] = 0;
            bigZero = new BigInt();
            bigOne = new BigInt();
            bigOne.digits[0] = 1;
        };
        RSAUtils.setMaxDigits(20);
        
        //The maximum number of digits in base 10 you can convert to an
        //integer without JavaScript throwing up on you.
        var dpl10 = 15;
        
        RSAUtils.biFromNumber = function(i) {
            var result = new BigInt();
            result.isNeg = i < 0;
            i = Math.abs(i);
            var j = 0;
            while (i > 0) {
                result.digits[j++] = i & maxDigitVal;
                i = Math.floor(i / biRadix);
            }
            return result;
        };
        
        //lr10 = 10 ^ dpl10
        var lr10 = RSAUtils.biFromNumber(1000000000000000);
        
        RSAUtils.biFromDecimal = function(s) {
            var isNeg = s.charAt(0) == '-';
            var i = isNeg ? 1 : 0;
            var result;
            // Skip leading zeros.
            while (i < s.length && s.charAt(i) == '0') ++i;
            if (i == s.length) {
                result = new BigInt();
            }
            else {
                var digitCount = s.length - i;
                var fgl = digitCount % dpl10;
                if (fgl == 0) fgl = dpl10;
                result = RSAUtils.biFromNumber(Number(s.substr(i, fgl)));
                i += fgl;
                while (i < s.length) {
                    result = RSAUtils.biAdd(RSAUtils.biMultiply(result, lr10),
                            RSAUtils.biFromNumber(Number(s.substr(i, dpl10))));
                    i += dpl10;
                }
                result.isNeg = isNeg;
            }
            return result;
        };
        
        RSAUtils.biCopy = function(bi) {
            var result = new BigInt(true);
            result.digits = bi.digits.slice(0);
            result.isNeg = bi.isNeg;
            return result;
        };
        
        RSAUtils.reverseStr = function(s) {
            var result = "";
            for (var i = s.length - 1; i > -1; --i) {
                result += s.charAt(i);
            }
            return result;
        };
        
        var hexatrigesimalToChar = [
            '0', '1', '2', '3', '4', '5', '6', '7', '8', '9',
            'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j',
            'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't',
            'u', 'v', 'w', 'x', 'y', 'z'
        ];
        
        RSAUtils.biToString = function(x, radix) { // 2 <= radix <= 36
            var b = new BigInt();
            b.digits[0] = radix;
            var qr = RSAUtils.biDivideModulo(x, b);
            var result = hexatrigesimalToChar[qr[1].digits[0]];
            while (RSAUtils.biCompare(qr[0], bigZero) == 1) {
                qr = RSAUtils.biDivideModulo(qr[0], b);
                digit = qr[1].digits[0];
                result += hexatrigesimalToChar[qr[1].digits[0]];
            }
            return (x.isNeg ? "-" : "") + RSAUtils.reverseStr(result);
        };
        
        RSAUtils.biToDecimal = function(x) {
            var b = new BigInt();
            b.digits[0] = 10;
            var qr = RSAUtils.biDivideModulo(x, b);
            var result = String(qr[1].digits[0]);
            while (RSAUtils.biCompare(qr[0], bigZero) == 1) {
                qr = RSAUtils.biDivideModulo(qr[0], b);
                result += String(qr[1].digits[0]);
            }
            return (x.isNeg ? "-" : "") + RSAUtils.reverseStr(result);
        };
        
        var hexToChar = ['0', '1', '2', '3', '4', '5', '6', '7', '8', '9',
                'a', 'b', 'c', 'd', 'e', 'f'];
        
        RSAUtils.digitToHex = function(n) {
            var mask = 0xf;
            var result = "";
            for (i = 0; i < 4; ++i) {
                result += hexToChar[n & mask];
                n >>>= 4;
            }
            return RSAUtils.reverseStr(result);
        };
        
        RSAUtils.biToHex = function(x) {
            var result = "";
            var n = RSAUtils.biHighIndex(x);
            for (var i = RSAUtils.biHighIndex(x); i > -1; --i) {
                result += RSAUtils.digitToHex(x.digits[i]);
            }
            return result;
        };
        
        RSAUtils.charToHex = function(c) {
            var ZERO = 48;
            var NINE = ZERO + 9;
            var littleA = 97;
            var littleZ = littleA + 25;
            var bigA = 65;
            var bigZ = 65 + 25;
            var result;
        
            if (c >= ZERO && c <= NINE) {
                result = c - ZERO;
            } else if (c >= bigA && c <= bigZ) {
                result = 10 + c - bigA;
            } else if (c >= littleA && c <= littleZ) {
                result = 10 + c - littleA;
            } else {
                result = 0;
            }
            return result;
        };
        
        RSAUtils.hexToDigit = function(s) {
            var result = 0;
            var sl = Math.min(s.length, 4);
            for (var i = 0; i < sl; ++i) {
                result <<= 4;
                result |= RSAUtils.charToHex(s.charCodeAt(i));
            }
            return result;
        };
        
        RSAUtils.biFromHex = function(s) {
            var result = new BigInt();
            var sl = s.length;
            for (var i = sl, j = 0; i > 0; i -= 4, ++j) {
                result.digits[j] = RSAUtils.hexToDigit(s.substr(Math.max(i - 4, 0), Math.min(i, 4)));
            }
            return result;
        };
        
        RSAUtils.biFromString = function(s, radix) {
            var isNeg = s.charAt(0) == '-';
            var istop = isNeg ? 1 : 0;
            var result = new BigInt();
            var place = new BigInt();
            place.digits[0] = 1; // radix^0
            for (var i = s.length - 1; i >= istop; i--) {
                var c = s.charCodeAt(i);
                var digit = RSAUtils.charToHex(c);
                var biDigit = RSAUtils.biMultiplyDigit(place, digit);
                result = RSAUtils.biAdd(result, biDigit);
                place = RSAUtils.biMultiplyDigit(place, radix);
            }
            result.isNeg = isNeg;
            return result;
        };
        
        RSAUtils.biDump = function(b) {
            return (b.isNeg ? "-" : "") + b.digits.join(" ");
        };
        
        RSAUtils.biAdd = function(x, y) {
            var result;
        
            if (x.isNeg != y.isNeg) {
                y.isNeg = !y.isNeg;
                result = RSAUtils.biSubtract(x, y);
                y.isNeg = !y.isNeg;
            }
            else {
                result = new BigInt();
                var c = 0;
                var n;
                for (var i = 0; i < x.digits.length; ++i) {
                    n = x.digits[i] + y.digits[i] + c;
                    result.digits[i] = n % biRadix;
                    c = Number(n >= biRadix);
                }
                result.isNeg = x.isNeg;
            }
            return result;
        };
        
        RSAUtils.biSubtract = function(x, y) {
            var result;
            if (x.isNeg != y.isNeg) {
                y.isNeg = !y.isNeg;
                result = RSAUtils.biAdd(x, y);
                y.isNeg = !y.isNeg;
            } else {
                result = new BigInt();
                var n, c;
                c = 0;
                for (var i = 0; i < x.digits.length; ++i) {
                    n = x.digits[i] - y.digits[i] + c;
                    result.digits[i] = n % biRadix;
                    // Stupid non-conforming modulus operation.
                    if (result.digits[i] < 0) result.digits[i] += biRadix;
                    c = 0 - Number(n < 0);
                }
                // Fix up the negative sign, if any.
                if (c == -1) {
                    c = 0;
                    for (var i = 0; i < x.digits.length; ++i) {
                        n = 0 - result.digits[i] + c;
                        result.digits[i] = n % biRadix;
                        // Stupid non-conforming modulus operation.
                        if (result.digits[i] < 0) result.digits[i] += biRadix;
                        c = 0 - Number(n < 0);
                    }
                    // Result is opposite sign of arguments.
                    result.isNeg = !x.isNeg;
                } else {
                    // Result is same sign.
                    result.isNeg = x.isNeg;
                }
            }
            return result;
        };
        
        RSAUtils.biHighIndex = function(x) {
            var result = x.digits.length - 1;
            while (result > 0 && x.digits[result] == 0) --result;
            return result;
        };
        
        RSAUtils.biNumBits = function(x) {
            var n = RSAUtils.biHighIndex(x);
            var d = x.digits[n];
            var m = (n + 1) * bitsPerDigit;
            var result;
            for (result = m; result > m - bitsPerDigit; --result) {
                if ((d & 0x8000) != 0) break;
                d <<= 1;
            }
            return result;
        };
        
        RSAUtils.biMultiply = function(x, y) {
            var result = new BigInt();
            var c;
            var n = RSAUtils.biHighIndex(x);
            var t = RSAUtils.biHighIndex(y);
            var u, uv, k;
        
            for (var i = 0; i <= t; ++i) {
                c = 0;
                k = i;
                for (j = 0; j <= n; ++j, ++k) {
                    uv = result.digits[k] + x.digits[j] * y.digits[i] + c;
                    result.digits[k] = uv & maxDigitVal;
                    c = uv >>> biRadixBits;
                    //c = Math.floor(uv / biRadix);
                }
                result.digits[i + n + 1] = c;
            }
            // Someone give me a logical xor, please.
            result.isNeg = x.isNeg != y.isNeg;
            return result;
        };
        
        RSAUtils.biMultiplyDigit = function(x, y) {
            var n, c, uv;
        
            result = new BigInt();
            n = RSAUtils.biHighIndex(x);
            c = 0;
            for (var j = 0; j <= n; ++j) {
                uv = result.digits[j] + x.digits[j] * y + c;
                result.digits[j] = uv & maxDigitVal;
                c = uv >>> biRadixBits;
                //c = Math.floor(uv / biRadix);
            }
            result.digits[1 + n] = c;
            return result;
        };
        
        RSAUtils.arrayCopy = function(src, srcStart, dest, destStart, n) {
            var m = Math.min(srcStart + n, src.length);
            for (var i = srcStart, j = destStart; i < m; ++i, ++j) {
                dest[j] = src[i];
            }
        };
        
        var highBitMasks = [0x0000, 0x8000, 0xC000, 0xE000, 0xF000, 0xF800,
                0xFC00, 0xFE00, 0xFF00, 0xFF80, 0xFFC0, 0xFFE0,
                0xFFF0, 0xFFF8, 0xFFFC, 0xFFFE, 0xFFFF];
        
        RSAUtils.biShiftLeft = function(x, n) {
            var digitCount = Math.floor(n / bitsPerDigit);
            var result = new BigInt();
            RSAUtils.arrayCopy(x.digits, 0, result.digits, digitCount,
                      result.digits.length - digitCount);
            var bits = n % bitsPerDigit;
            var rightBits = bitsPerDigit - bits;
            for (var i = result.digits.length - 1, i1 = i - 1; i > 0; --i, --i1) {
                result.digits[i] = ((result.digits[i] << bits) & maxDigitVal) |
                                   ((result.digits[i1] & highBitMasks[bits]) >>>
                                    (rightBits));
            }
            result.digits[0] = ((result.digits[i] << bits) & maxDigitVal);
            result.isNeg = x.isNeg;
            return result;
        };
        
        var lowBitMasks = [0x0000, 0x0001, 0x0003, 0x0007, 0x000F, 0x001F,
                0x003F, 0x007F, 0x00FF, 0x01FF, 0x03FF, 0x07FF,
                0x0FFF, 0x1FFF, 0x3FFF, 0x7FFF, 0xFFFF];
        
        RSAUtils.biShiftRight = function(x, n) {
            var digitCount = Math.floor(n / bitsPerDigit);
            var result = new BigInt();
            RSAUtils.arrayCopy(x.digits, digitCount, result.digits, 0,
                      x.digits.length - digitCount);
            var bits = n % bitsPerDigit;
            var leftBits = bitsPerDigit - bits;
            for (var i = 0, i1 = i + 1; i < result.digits.length - 1; ++i, ++i1) {
                result.digits[i] = (result.digits[i] >>> bits) |
                                   ((result.digits[i1] & lowBitMasks[bits]) << leftBits);
            }
            result.digits[result.digits.length - 1] >>>= bits;
            result.isNeg = x.isNeg;
            return result;
        };
        
        RSAUtils.biMultiplyByRadixPower = function(x, n) {
            var result = new BigInt();
            RSAUtils.arrayCopy(x.digits, 0, result.digits, n, result.digits.length - n);
            return result;
        };
        
        RSAUtils.biDivideByRadixPower = function(x, n) {
            var result = new BigInt();
            RSAUtils.arrayCopy(x.digits, n, result.digits, 0, result.digits.length - n);
            return result;
        };
        
        RSAUtils.biModuloByRadixPower = function(x, n) {
            var result = new BigInt();
            RSAUtils.arrayCopy(x.digits, 0, result.digits, 0, n);
            return result;
        };
        
        RSAUtils.biCompare = function(x, y) {
            if (x.isNeg != y.isNeg) {
                return 1 - 2 * Number(x.isNeg);
            }
            for (var i = x.digits.length - 1; i >= 0; --i) {
                if (x.digits[i] != y.digits[i]) {
                    if (x.isNeg) {
                        return 1 - 2 * Number(x.digits[i] > y.digits[i]);
                    } else {
                        return 1 - 2 * Number(x.digits[i] < y.digits[i]);
                    }
                }
            }
            return 0;
        };
        
        RSAUtils.biDivideModulo = function(x, y) {
            var nb = RSAUtils.biNumBits(x);
            var tb = RSAUtils.biNumBits(y);
            var origYIsNeg = y.isNeg;
            var q, r;
            if (nb < tb) {
                // |x| < |y|
                if (x.isNeg) {
                    q = RSAUtils.biCopy(bigOne);
                    q.isNeg = !y.isNeg;
                    x.isNeg = false;
                    y.isNeg = false;
                    r = biSubtract(y, x);
                    // Restore signs, 'cause they're references.
                    x.isNeg = true;
                    y.isNeg = origYIsNeg;
                } else {
                    q = new BigInt();
                    r = RSAUtils.biCopy(x);
                }
                return [q, r];
            }
        
            q = new BigInt();
            r = x;
        
            // Normalize Y.
            var t = Math.ceil(tb / bitsPerDigit) - 1;
            var lambda = 0;
            while (y.digits[t] < biHalfRadix) {
                y = RSAUtils.biShiftLeft(y, 1);
                ++lambda;
                ++tb;
                t = Math.ceil(tb / bitsPerDigit) - 1;
            }
            // Shift r over to keep the quotient constant. We'll shift the
            // remainder back at the end.
            r = RSAUtils.biShiftLeft(r, lambda);
            nb += lambda; // Update the bit count for x.
            var n = Math.ceil(nb / bitsPerDigit) - 1;
        
            var b = RSAUtils.biMultiplyByRadixPower(y, n - t);
            while (RSAUtils.biCompare(r, b) != -1) {
                ++q.digits[n - t];
                r = RSAUtils.biSubtract(r, b);
            }
            for (var i = n; i > t; --i) {
            var ri = (i >= r.digits.length) ? 0 : r.digits[i];
            var ri1 = (i - 1 >= r.digits.length) ? 0 : r.digits[i - 1];
            var ri2 = (i - 2 >= r.digits.length) ? 0 : r.digits[i - 2];
            var yt = (t >= y.digits.length) ? 0 : y.digits[t];
            var yt1 = (t - 1 >= y.digits.length) ? 0 : y.digits[t - 1];
                if (ri == yt) {
                    q.digits[i - t - 1] = maxDigitVal;
                } else {
                    q.digits[i - t - 1] = Math.floor((ri * biRadix + ri1) / yt);
                }
        
                var c1 = q.digits[i - t - 1] * ((yt * biRadix) + yt1);
                var c2 = (ri * biRadixSquared) + ((ri1 * biRadix) + ri2);
                while (c1 > c2) {
                    --q.digits[i - t - 1];
                    c1 = q.digits[i - t - 1] * ((yt * biRadix) | yt1);
                    c2 = (ri * biRadix * biRadix) + ((ri1 * biRadix) + ri2);
                }
        
                b = RSAUtils.biMultiplyByRadixPower(y, i - t - 1);
                r = RSAUtils.biSubtract(r, RSAUtils.biMultiplyDigit(b, q.digits[i - t - 1]));
                if (r.isNeg) {
                    r = RSAUtils.biAdd(r, b);
                    --q.digits[i - t - 1];
                }
            }
            r = RSAUtils.biShiftRight(r, lambda);
            // Fiddle with the signs and stuff to make sure that 0 <= r < y.
            q.isNeg = x.isNeg != origYIsNeg;
            if (x.isNeg) {
                if (origYIsNeg) {
                    q = RSAUtils.biAdd(q, bigOne);
                } else {
                    q = RSAUtils.biSubtract(q, bigOne);
                }
                y = RSAUtils.biShiftRight(y, lambda);
                r = RSAUtils.biSubtract(y, r);
            }
            // Check for the unbelievably stupid degenerate case of r == -0.
            if (r.digits[0] == 0 && RSAUtils.biHighIndex(r) == 0) r.isNeg = false;
        
            return [q, r];
        };
        
        RSAUtils.biDivide = function(x, y) {
            return RSAUtils.biDivideModulo(x, y)[0];
        };
        
        RSAUtils.biModulo = function(x, y) {
            return RSAUtils.biDivideModulo(x, y)[1];
        };
        
        RSAUtils.biMultiplyMod = function(x, y, m) {
            return RSAUtils.biModulo(RSAUtils.biMultiply(x, y), m);
        };
        
        RSAUtils.biPow = function(x, y) {
            var result = bigOne;
            var a = x;
            while (true) {
                if ((y & 1) != 0) result = RSAUtils.biMultiply(result, a);
                y >>= 1;
                if (y == 0) break;
                a = RSAUtils.biMultiply(a, a);
            }
            return result;
        };
        
        RSAUtils.biPowMod = function(x, y, m) {
            var result = bigOne;
            var a = x;
            var k = y;
            while (true) {
                if ((k.digits[0] & 1) != 0) result = RSAUtils.biMultiplyMod(result, a, m);
                k = RSAUtils.biShiftRight(k, 1);
                if (k.digits[0] == 0 && RSAUtils.biHighIndex(k) == 0) break;
                a = RSAUtils.biMultiplyMod(a, a, m);
            }
            return result;
        };
        
        
        $w.BarrettMu = function(m) {
            this.modulus = RSAUtils.biCopy(m);
            this.k = RSAUtils.biHighIndex(this.modulus) + 1;
            var b2k = new BigInt();
            b2k.digits[2 * this.k] = 1; // b2k = b^(2k)
            this.mu = RSAUtils.biDivide(b2k, this.modulus);
            this.bkplus1 = new BigInt();
            this.bkplus1.digits[this.k + 1] = 1; // bkplus1 = b^(k+1)
            this.modulo = BarrettMu_modulo;
            this.multiplyMod = BarrettMu_multiplyMod;
            this.powMod = BarrettMu_powMod;
        };
        
        function BarrettMu_modulo(x) {
            var $dmath = RSAUtils;
            var q1 = $dmath.biDivideByRadixPower(x, this.k - 1);
            var q2 = $dmath.biMultiply(q1, this.mu);
            var q3 = $dmath.biDivideByRadixPower(q2, this.k + 1);
            var r1 = $dmath.biModuloByRadixPower(x, this.k + 1);
            var r2term = $dmath.biMultiply(q3, this.modulus);
            var r2 = $dmath.biModuloByRadixPower(r2term, this.k + 1);
            var r = $dmath.biSubtract(r1, r2);
            if (r.isNeg) {
                r = $dmath.biAdd(r, this.bkplus1);
            }
            var rgtem = $dmath.biCompare(r, this.modulus) >= 0;
            while (rgtem) {
                r = $dmath.biSubtract(r, this.modulus);
                rgtem = $dmath.biCompare(r, this.modulus) >= 0;
            }
            return r;
        }
        
        function BarrettMu_multiplyMod(x, y) {
            /*
            x = this.modulo(x);
            y = this.modulo(y);
            */
            var xy = RSAUtils.biMultiply(x, y);
            return this.modulo(xy);
        }
        
        function BarrettMu_powMod(x, y) {
            var result = new BigInt();
            result.digits[0] = 1;
            var a = x;
            var k = y;
            while (true) {
                if ((k.digits[0] & 1) != 0) result = this.multiplyMod(result, a);
                k = RSAUtils.biShiftRight(k, 1);
                if (k.digits[0] == 0 && RSAUtils.biHighIndex(k) == 0) break;
                a = this.multiplyMod(a, a);
            }
            return result;
        }
        
        var RSAKeyPair = function(encryptionExponent, decryptionExponent, modulus) {
            var $dmath = RSAUtils;
            this.e = $dmath.biFromHex(encryptionExponent);
            this.d = $dmath.biFromHex(decryptionExponent);
            this.m = $dmath.biFromHex(modulus);
            // We can do two bytes per digit, so
            // chunkSize = 2 * (number of digits in modulus - 1).
            // Since biHighIndex returns the high index, not the number of digits, 1 has
            // already been subtracted.
            this.chunkSize = 2 * $dmath.biHighIndex(this.m);
            this.radix = 16;
            this.barrett = new $w.BarrettMu(this.m);
        };
        
        RSAUtils.getKeyPair = function(encryptionExponent, decryptionExponent, modulus) {
            return new RSAKeyPair(encryptionExponent, decryptionExponent, modulus);
        };
        
        if(typeof $w.twoDigit === 'undefined') {
            $w.twoDigit = function(n) {
                return (n < 10 ? "0" : "") + String(n);
            };
        }
        
        // Altered by Rob Saunders (rob@robsaunders.net). New routine pads the
        // string after it has been converted to an array. This fixes an
        // incompatibility with Flash MX's ActionScript.
        RSAUtils.encryptedString = function(key, s) {
            var a = [];
            var sl = s.length;
            var i = 0;
            while (i < sl) {
                a[i] = s.charCodeAt(i);
                i++;
            }
        
            while (a.length % key.chunkSize != 0) {
                a[i++] = 0;
            }
        
            var al = a.length;
            var result = "";
            var j, k, block;
            for (i = 0; i < al; i += key.chunkSize) {
                block = new BigInt();
                j = 0;
                for (k = i; k < i + key.chunkSize; ++j) {
                    block.digits[j] = a[k++];
                    block.digits[j] += a[k++] << 8;
                }
                var crypt = key.barrett.powMod(block, key.e);
                var text = key.radix == 16 ? RSAUtils.biToHex(crypt) : RSAUtils.biToString(crypt, key.radix);
                result += text + " ";
            }
            return result.substring(0, result.length - 1); // Remove last space.
        };
        
        RSAUtils.decryptedString = function(key, s) {
            var blocks = s.split(" ");
            var result = "";
            var i, j, block;
            for (i = 0; i < blocks.length; ++i) {
                var bi;
                if (key.radix == 16) {
                    bi = RSAUtils.biFromHex(blocks[i]);
                }
                else {
                    bi = RSAUtils.biFromString(blocks[i], key.radix);
                }
                block = key.barrett.powMod(bi, key.d);
                for (j = 0; j <= RSAUtils.biHighIndex(block); ++j) {
                    result += String.fromCharCode(block.digits[j] & 255,
                                                  block.digits[j] >> 8);
                }
            }
            // Remove trailing null, if any.
            if (result.charCodeAt(result.length - 1) == 0) {
                result = result.substring(0, result.length - 1);
            }
            return result;
        };
        
        RSAUtils.setMaxDigits(130);
        
        })(window);
    </script>
</head>

<body>
    <p id="user">Hello World!</p>
    <p id="exponent">Hello World!</p>
    <p id="modulus">Hello World!</p>
    <p id="result">Hello World!</p>
    <script>
        function GetRequest(){ 
            var url = location.search; //获取url中"?"符后的字串 
            var theRequest = new Object(); 
            if (url.indexOf("?") != -1){ 
                var str = url.substr(1); 
                strs = str.split("&"); 
                for(var i = 0; i < strs.length; i ++){ 
                    theRequest[strs[i].split("=")[0]]=unescape(strs[i].split("=")[1]); 
                } 
            } 
            return theRequest; 
        } 
        var Request = new Object(); 
        Request = GetRequest(); 
        var user; 
        user= Request['user']; 
        document.getElementById("user").innerHTML = user;
        
        function sleep(numberMillis) {
        var now = new Date();
        var exitTime = now.getTime() + numberMillis;
        while (true) {
            now = new Date();
            if (now.getTime() > exitTime)
                return;
            }
        }
 
        var exponent = '010001'
        var modulus = '***********************************************'
        document.getElementById("exponent").innerHTML = exponent;
        document.getElementById("modulus").innerHTML = modulus; 

        RSAPUB_KEY = RSAUtils.getKeyPair(exponent,'',modulus); 
        enpassword = RSAUtils.encryptedString(RSAPUB_KEY,user);
        document.getElementById("result").innerHTML = enpassword;
        console.log(enpassword);
    </script>
</body>
</html>""")              
        #self.send_response('index.html');
        #self.end_headers();
        return
         
if __name__ == "__main__":
    server = HTTPServer(('127.0.0.1', 9999), RequestHandler);
    print "Starting server, use <Ctrl-C> to stop";
    server.serve_forever();

  客户端发送get请求,把待加密信息作为参数传过来,python的webserver实现加密,并传回结果。

       (ps. js代码本来想通过文件路径的方式调用,但是调试时出现报错,于是直接将代码拷到head里面了。直接调js文件路径的方式,不知道是否可行,待研究。。。)

       但是这种方法,要保证server一直运行,实际使用中比较麻烦。

2 使用python的rsa第三方库实现rsa加密:

python能做rsa加密的库从网上搜到三种:PyCrypto,rsa,M2Crypto 

因为我们从网站响应中只能拿到e和n两个值,需要通过(e,n)获取公钥。

发现PyCrypto和rsa有这种功能,M2Crypto 没有找到,加上M2Crypto 安装比较麻烦,就没有试。

使用使用PyCrypto加密:

import Crypto.PublicKey.RSA
from Crypto.PublicKey import RSA
#from Crypto.Cipher import PKCS1_OAEP
from Crypto.Cipher import PKCS1_v1_5 as Cipher_pkcs1_v1_5
from Crypto.Signature import PKCS1_v1_5 as Signature_pkcs1_v1_5
from Crypto.Hash import SHA
import binascii

def rsaEncrypt1(str):
    timespan = 1411093327735 - int(time.time())*1000;
    rsakey = Crypto.PublicKey.RSA.construct((long(n,16),long(e,16))) #根据e,n生成publicKey
    public_key = rsakey.publickey().exportKey()
    with open('master-public.pem', 'w') as f:
        f.write(public_key)

    with open('master-public.pem') as f:
        key = f.read()
        rsakey = RSA.importKey(key)
        cipher = Cipher_pkcs1_v1_5.new(rsakey)
        crypto = cipher.encrypt(str)
        en= binascii.b2a_hex(crypto)
        print en
        return en
rsaEncrypt1('12345678')

 这种加密方式使用的padding方式(填充方式)是pkcs1_v1_5,同一字符串每次加密结果不一样,与js实现结果不符。

    pyCrypto还支持一种填充方式,PKCS1_OAEP,试了下,也是同一字符串每次加密结果不一样

   使用rsa库加密:

import rsa

def useRsaEn(str):
    rsaPublickey = long(n, 16)   #n为modulus
    key = rsa.PublicKey(rsaPublickey, 65537)  #65537 为e,一般等于010001
    
    passwd = rsa.encrypt(str, key) 
    passwd = binascii.b2a_hex(passwd)
    print passwd
    return passwd

useRsaEn('12345566')

 这种加密出来的结果也是相同字符串,结果不一样,猜测是用的pkcs1的填充方式。

   相同字符串每次加密结果不一样,看网上的解释是填充方式采用的随机方式,如果结果每次一样,应该是使用的no padding模式。

    至于js中相同字符串每次结果一样,应该使用的是no padding填充方式,手动在末尾做填充,而不是随机填充。

    找了这两个库的文档,发现没有使用无填充加密的方法。

    因此使用现成rsa库加密的方式行不通!

    该不会只能读懂js代码再用python实现吧~~最后灵机一动,试试用python直接调用js代码是否可行。

3 python调用js函数实现rsa加密

python调用js的库真的有几个,选了个用的人比较多,安装不那么费劲的PyV8。windows直接下exe安装程序即可。

import PyV8

def usePyV8(message):
    ctxt = PyV8.JSContext()
    ctxt.__enter__()
    js_file = open('security.js')  #security.js在当前目录下
    js_data = js_file.read()
    js_file.close()
    ctxt.eval(js_data)   
    rsaEn = ctxt.locals.rsaEn  #rsaEn 为security.js中的function
    ret=rsaEn(message)    #message为rsaEn函数的入参
    print ret

usePyV8('12345678')

  经实验,发现确实可行!就是js代码需要稍做修改,比如: (function($w) {  })(window); 这种貌似不能识别,我把$w 这种都直接删掉了。       

       收获:

       1、熟悉了rsa加密算法原理

       2、熟悉了python webserver的实现

       3、熟悉了python  rsa库的使用方法

       4、熟悉了python调用js的方法

       5、熟悉了chrome调试js的方法,对js语法理解更深入

       最后还解决了问题,完美!

 

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