逆向案例二十四——投某界登录接口逆向，扣代码

网址：aHR0cHM6Ly91c2VyLnBlZGFpbHkuY24vbG9naW4uYXNweA==

抓包登录接口：

在登录界面登录，不然不会出现login的js文件，按关键词搜索，进入loginjs文件，在文件中搜索，找到疑似加密的位置，打上断点，重新登陆。

在控制台打印疑似参数，hex_sha1是加密函数。

$('#form_login #pwd').val(hex_sha1($('#form_login #password').val()))

这行代码通过 jQuery 选择器获取了 id 为 form_login 的表单内部 id 为 password 的输入框的值，然后使用 hex_sha1 函数对其进行 SHA-1 加密，最后将加密后的结果设置为 id 为 form_login 的表单内部 id 为 pwd 的输入框的值。

具体来说：

• $('#form_login #password').val() 获取 id 为 form_login 的表单内部 id 为 password 的输入框的值。
• hex_sha1($('#form_login #password').val()) 对获取的密码值进行 SHA-1 加密。
• $('#form_login #pwd').val(...) 将加密后的结果设置为 id 为 form_login 的表单内部 id 为 pwd 的输入框的值。

鼠标覆盖hex_sha1,进入加密函数所在的js代码。选中的函数就是加密函数，这个文件应该全是用来加密解密的，可以全部复制，在最后一行打印console.log(hex_sha1(123456)),然后复制整个js文件，先在浏览器环境运行。

打开一个页面——打开新的开发者工具——打开源代码来源—— 代码段——添加新的代码段——执行。发现可以运行成功。再复制到pycharm中运行。

代码展现： 

/*  
 * A JavaScript implementation of the Secure Hash Algorithm, SHA-1, as defined  
 * in FIPS 180-1  
 * Version 2.2 Copyright Paul Johnston 2000 - 2009.  
 * Other contributors: Greg Holt, Andrew Kepert, Ydnar, Lostinet  
 * Distributed under the BSD License  
 * See http://pajhome.org.uk/crypt/md5 for details.  
 */  
  
/*  
 * Configurable variables. You may need to tweak these to be compatible with  
 * the server-side, but the defaults work in most cases.  
 */  
var hexcase = 1;  /* hex output format. 0 - lowercase; 1 - uppercase        */  
var b64pad  = ""; /* base-64 pad character. "=" for strict RFC compliance   */  
  
/*  
 * These are the functions you'll usually want to call  
 * They take string arguments and return either hex or base-64 encoded strings  
 */  
function hex_sha1(s)    { return rstr2hex(rstr_sha1(str2rstr_utf8(s))); }   
function b64_sha1(s)    { return rstr2b64(rstr_sha1(str2rstr_utf8(s))); }   
function any_sha1(s, e) { return rstr2any(rstr_sha1(str2rstr_utf8(s)), e); }   
function hex_hmac_sha1(k, d)   
  { return rstr2hex(rstr_hmac_sha1(str2rstr_utf8(k), str2rstr_utf8(d))); }   
function b64_hmac_sha1(k, d)   
  { return rstr2b64(rstr_hmac_sha1(str2rstr_utf8(k), str2rstr_utf8(d))); }   
function any_hmac_sha1(k, d, e)   
  { return rstr2any(rstr_hmac_sha1(str2rstr_utf8(k), str2rstr_utf8(d)), e); }   
  
/*  
 * Perform a simple self-test to see if the VM is working  
 */  
function sha1_vm_test()   
{   
  return hex_sha1("abc").toLowerCase() == "a9993e364706816aba3e25717850c26c9cd0d89d";   
}   
  
/*  
 * Calculate the SHA1 of a raw string  
 */  
function rstr_sha1(s)   
{   
  return binb2rstr(binb_sha1(rstr2binb(s), s.length * 8));   
}   
  
/*  
 * Calculate the HMAC-SHA1 of a key and some data (raw strings)  
 */  
function rstr_hmac_sha1(key, data)   
{   
  var bkey = rstr2binb(key);   
  if(bkey.length > 16) bkey = binb_sha1(bkey, key.length * 8);   
  
  var ipad = Array(16), opad = Array(16);   
  for(var i = 0; i < 16; i++)   
  {cd44bf3750501c57fa3b57729711adee67d9c0   
    ipad[i] = bkey[i] ^ 0x36363636;   
    opad[i] = bkey[i] ^ 0x5C5C5C5C;   
  }   
  
  var hash = binb_sha1(ipad.concat(rstr2binb(data)), 512 + data.length * 8);   
  return binb2rstr(binb_sha1(opad.concat(hash), 512 + 160));   
}   
  
/*  
 * Convert a raw string to a hex string  
 */  
function rstr2hex(input)   
{   
  try { hexcase } catch(e) { hexcase=0; }   
  var hex_tab = hexcase ? "0123456789ABCDEF" : "0123456789abcdef";   
  var output = "";   
  var x;   
  for(var i = 0; i < input.length; i++)   
  {   
    x = input.charCodeAt(i);   
    output += hex_tab.charAt((x >>> 4) & 0x0F)   
           +  hex_tab.charAt( x        & 0x0F);   
  }   
  return output;   
}   
  
/*  
 * Convert a raw string to a base-64 string  
 */  
function rstr2b64(input)   
{   
  try { b64pad } catch(e) { b64pad=''; }   
  var tab = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";   
  var output = "";   
  var len = input.length;   
  for(var i = 0; i < len; i += 3)   
  {   
    var triplet = (input.charCodeAt(i) << 16)   
                | (i + 1 < len ? input.charCodeAt(i+1) << 8 : 0)   
                | (i + 2 < len ? input.charCodeAt(i+2)      : 0);   
    for(var j = 0; j < 4; j++)   
    {   
      if(i * 8 + j * 6 > input.length * 8) output += b64pad;   
      else output += tab.charAt((triplet >>> 6*(3-j)) & 0x3F);   
    }   
  }   
  return output;   
}   
  
/*  
 * Convert a raw string to an arbitrary string encoding  
 */  
function rstr2any(input, encoding)   
{   
  var divisor = encoding.length;   
  var remainders = Array();   
  var i, q, x, quotient;   
  
  /* Convert to an array of 16-bit big-endian values, forming the dividend */  
  var dividend = Array(Math.ceil(input.length / 2));   
  for(i = 0; i < dividend.length; i++)   
  {   
    dividend[i] = (input.charCodeAt(i * 2) << 8) | input.charCodeAt(i * 2 + 1);   
  }   
  
  /*  
   * Repeatedly perform a long division. The binary array forms the dividend,  
   * the length of the encoding is the divisor. Once computed, the quotient  
   * forms the dividend for the next step. We stop when the dividend is zero.  
   * All remainders are stored for later use.  
   */  
  while(dividend.length > 0)   
  {   
    quotient = Array();   
    x = 0;   
    for(i = 0; i < dividend.length; i++)   
    {   
      x = (x << 16) + dividend[i];   
      q = Math.floor(x / divisor);   
      x -= q * divisor;   
      if(quotient.length > 0 || q > 0)   
        quotient[quotient.length] = q;   
    }   
    remainders[remainders.length] = x;   
    dividend = quotient;   
  }   
  
  /* Convert the remainders to the output string */  
  var output = "";   
  for(i = remainders.length - 1; i >= 0; i--)   
    output += encoding.charAt(remainders[i]);   
  
  /* Append leading zero equivalents */  
  var full_length = Math.ceil(input.length * 8 /   
                                    (Math.log(encoding.length) / Math.log(2)))   
  for(i = output.length; i < full_length; i++)   
    output = encoding[0] + output;   
  
  return output;   
}   
  
/*  
 * Encode a string as utf-8.  
 * For efficiency, this assumes the input is valid utf-16.  
 */  
function str2rstr_utf8(input)   
{   
  var output = "";   
  var i = -1;   
  var x, y;   
  
  while(++i < input.length)   
  {   
    /* Decode utf-16 surrogate pairs */  
    x = input.charCodeAt(i);   
    y = i + 1 < input.length ? input.charCodeAt(i + 1) : 0;   
    if(0xD800 <= x && x <= 0xDBFF && 0xDC00 <= y && y <= 0xDFFF)   
    {   
      x = 0x10000 + ((x & 0x03FF) << 10) + (y & 0x03FF);   
      i++;   
    }   
  
    /* Encode output as utf-8 */  
    if(x <= 0x7F)   
      output += String.fromCharCode(x);   
    else if(x <= 0x7FF)   
      output += String.fromCharCode(0xC0 | ((x >>> 6 ) & 0x1F),   
                                    0x80 | ( x         & 0x3F));   
    else if(x <= 0xFFFF)   
      output += String.fromCharCode(0xE0 | ((x >>> 12) & 0x0F),   
                                    0x80 | ((x >>> 6 ) & 0x3F),   
                                    0x80 | ( x         & 0x3F));   
    else if(x <= 0x1FFFFF)   
      output += String.fromCharCode(0xF0 | ((x >>> 18) & 0x07),   
                                    0x80 | ((x >>> 12) & 0x3F),   
                                    0x80 | ((x >>> 6 ) & 0x3F),   
                                    0x80 | ( x         & 0x3F));   
  }   
  return output;   
}   
  
/*  
 * Encode a string as utf-16  
 */  
function str2rstr_utf16le(input)   
{   
  var output = "";   
  for(var i = 0; i < input.length; i++)   
    output += String.fromCharCode( input.charCodeAt(i)        & 0xFF,   
                                  (input.charCodeAt(i) >>> 8) & 0xFF);   
  return output;   
}   
  
function str2rstr_utf16be(input)   
{   
  var output = "";   
  for(var i = 0; i < input.length; i++)   
    output += String.fromCharCode((input.charCodeAt(i) >>> 8) & 0xFF,   
                                   input.charCodeAt(i)        & 0xFF);   
  return output;   
}   
  
/*  
 * Convert a raw string to an array of big-endian words  
 * Characters >255 have their high-byte silently ignored.  
 */  
function rstr2binb(input)   
{   
  var output = Array(input.length >> 2);   
  for(var i = 0; i < output.length; i++)   
    output[i] = 0;   
  for(var i = 0; i < input.length * 8; i += 8)   
    output[i>>5] |= (input.charCodeAt(i / 8) & 0xFF) << (24 - i % 32);   
  return output;   
}   
  
/*  
 * Convert an array of big-endian words to a string  
 */  
function binb2rstr(input)   
{   
  var output = "";   
  for(var i = 0; i < input.length * 32; i += 8)   
    output += String.fromCharCode((input[i>>5] >>> (24 - i % 32)) & 0xFF);   
  return output;   
}   
  
/*  
 * Calculate the SHA-1 of an array of big-endian words, and a bit length  
 */  
function binb_sha1(x, len)   
{   
  /* append padding */  
  x[len >> 5] |= 0x80 << (24 - len % 32);   
  x[((len + 64 >> 9) << 4) + 15] = len;   
  
  var w = Array(80);   
  var a =  1732584193;   
  var b = -271733879;   
  var c = -1732584194;   
  var d =  271733878;   
  var e = -1009589776;   
  
  for(var i = 0; i < x.length; i += 16)   
  {   
    var olda = a;   
    var oldb = b;   
    var oldc = c;   
    var oldd = d;   
    var olde = e;   
  
    for(var j = 0; j < 80; j++)   
    {   
      if(j < 16) w[j] = x[i + j];   
      else w[j] = bit_rol(w[j-3] ^ w[j-8] ^ w[j-14] ^ w[j-16], 1);   
      var t = safe_add(safe_add(bit_rol(a, 5), sha1_ft(j, b, c, d)),   
                       safe_add(safe_add(e, w[j]), sha1_kt(j)));   
      e = d;   
      d = c;   
      c = bit_rol(b, 30);   
      b = a;   
      a = t;   
    }   
  
    a = safe_add(a, olda);   
    b = safe_add(b, oldb);   
    c = safe_add(c, oldc);   
    d = safe_add(d, oldd);   
    e = safe_add(e, olde);   
  }   
  return Array(a, b, c, d, e);   
  
}   
  
/*  
 * Perform the appropriate triplet combination function for the current  
 * iteration  
 */  
function sha1_ft(t, b, c, d)   
{   
  if(t < 20) return (b & c) | ((~b) & d);   
  if(t < 40) return b ^ c ^ d;   
  if(t < 60) return (b & c) | (b & d) | (c & d);   
  return b ^ c ^ d;   
}   
  
/*  
 * Determine the appropriate additive constant for the current iteration  
 */  
function sha1_kt(t)   
{   
  return (t < 20) ?  1518500249 : (t < 40) ?  1859775393 :   
         (t < 60) ? -1894007588 : -899497514;   
}   
  
/*  
 * Add integers, wrapping at 2^32. This uses 16-bit operations internally  
 * to work around bugs in some JS interpreters.  
 */  
function safe_add(x, y)   
{   
  var lsw = (x & 0xFFFF) + (y & 0xFFFF);   
  var msw = (x >> 16) + (y >> 16) + (lsw >> 16);   
  return (msw << 16) | (lsw & 0xFFFF);   
}   
  
/*  
 * Bitwise rotate a 32-bit number to the left.  
 */  
function bit_rol(num, cnt)   
{   
  return (num << cnt) | (num >>> (32 - cnt));   
}  
console.log(hex_sha1('123456'))

尝试着用标准库进行加密，发现结果是一样的，所以这是一个标准的sha1加密。

// 引入 CryptoJS 库
const CryptoJS = require("crypto-js");

// 定义待加密的字符串
const plaintext = "123456";

// 对字符串进行 SHA-1 加密
const sha1Digest = CryptoJS.SHA1(plaintext).toString();

// 打印加密结果
console.log("SHA-1 Digest:", sha1Digest);