一般在项目中,我们为了保证接口的安全,都会使用签名验证。而生成签名,则需要对排序后的字符串进行md5加密。
然而在微信小程序中,没有自带的md5加密函数,于是我便在百度上寻找了以下代码:
/* * A JavaScript implementation of the RSA Data Security, Inc. MD5 Message * Digest Algorithm, as defined in RFC 1321. * Version 1.1 Copyright (C) Paul Johnston 1999 - 2002. * Code also contributed by Greg Holt * See http://pajhome.org.uk/site/legal.html for details. */ /* * 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 rol(num, cnt) { return (num << cnt) | (num >>> (32 - cnt)) } /* * These functions implement the four basic operations the algorithm uses. */ function cmn(q, a, b, x, s, t) { return safe_add(rol(safe_add(safe_add(a, q), safe_add(x, t)), s), b) } function ff(a, b, c, d, x, s, t) { return cmn((b & c) | ((~b) & d), a, b, x, s, t) } function gg(a, b, c, d, x, s, t) { return cmn((b & d) | (c & (~d)), a, b, x, s, t) } function hh(a, b, c, d, x, s, t) { return cmn(b ^ c ^ d, a, b, x, s, t) } function ii(a, b, c, d, x, s, t) { return cmn(c ^ (b | (~d)), a, b, x, s, t) } /* * Calculate the MD5 of an array of little-endian words, producing an array * of little-endian words. */ function coreMD5(x) { var a = 1732584193 var b = -271733879 var c = -1732584194 var d = 271733878 for (var i = 0; i < x.length; i += 16) { var olda = a var oldb = b var oldc = c var oldd = d a = ff(a, b, c, d, x[i + 0], 7, -680876936) d = ff(d, a, b, c, x[i + 1], 12, -389564586) c = ff(c, d, a, b, x[i + 2], 17, 606105819) b = ff(b, c, d, a, x[i + 3], 22, -1044525330) a = ff(a, b, c, d, x[i + 4], 7, -176418897) d = ff(d, a, b, c, x[i + 5], 12, 1200080426) c = ff(c, d, a, b, x[i + 6], 17, -1473231341) b = ff(b, c, d, a, x[i + 7], 22, -45705983) a = ff(a, b, c, d, x[i + 8], 7, 1770035416) d = ff(d, a, b, c, x[i + 9], 12, -1958414417) c = ff(c, d, a, b, x[i + 10], 17, -42063) b = ff(b, c, d, a, x[i + 11], 22, -1990404162) a = ff(a, b, c, d, x[i + 12], 7, 1804603682) d = ff(d, a, b, c, x[i + 13], 12, -40341101) c = ff(c, d, a, b, x[i + 14], 17, -1502002290) b = ff(b, c, d, a, x[i + 15], 22, 1236535329) a = gg(a, b, c, d, x[i + 1], 5, -165796510) d = gg(d, a, b, c, x[i + 6], 9, -1069501632) c = gg(c, d, a, b, x[i + 11], 14, 643717713) b = gg(b, c, d, a, x[i + 0], 20, -373897302) a = gg(a, b, c, d, x[i + 5], 5, -701558691) d = gg(d, a, b, c, x[i + 10], 9, 38016083) c = gg(c, d, a, b, x[i + 15], 14, -660478335) b = gg(b, c, d, a, x[i + 4], 20, -405537848) a = gg(a, b, c, d, x[i + 9], 5, 568446438) d = gg(d, a, b, c, x[i + 14], 9, -1019803690) c = gg(c, d, a, b, x[i + 3], 14, -187363961) b = gg(b, c, d, a, x[i + 8], 20, 1163531501) a = gg(a, b, c, d, x[i + 13], 5, -1444681467) d = gg(d, a, b, c, x[i + 2], 9, -51403784) c = gg(c, d, a, b, x[i + 7], 14, 1735328473) b = gg(b, c, d, a, x[i + 12], 20, -1926607734) a = hh(a, b, c, d, x[i + 5], 4, -378558) d = hh(d, a, b, c, x[i + 8], 11, -2022574463) c = hh(c, d, a, b, x[i + 11], 16, 1839030562) b = hh(b, c, d, a, x[i + 14], 23, -35309556) a = hh(a, b, c, d, x[i + 1], 4, -1530992060) d = hh(d, a, b, c, x[i + 4], 11, 1272893353) c = hh(c, d, a, b, x[i + 7], 16, -155497632) b = hh(b, c, d, a, x[i + 10], 23, -1094730640) a = hh(a, b, c, d, x[i + 13], 4, 681279174) d = hh(d, a, b, c, x[i + 0], 11, -358537222) c = hh(c, d, a, b, x[i + 3], 16, -722521979) b = hh(b, c, d, a, x[i + 6], 23, 76029189) a = hh(a, b, c, d, x[i + 9], 4, -640364487) d = hh(d, a, b, c, x[i + 12], 11, -421815835) c = hh(c, d, a, b, x[i + 15], 16, 530742520) b = hh(b, c, d, a, x[i + 2], 23, -995338651) a = ii(a, b, c, d, x[i + 0], 6, -198630844) d = ii(d, a, b, c, x[i + 7], 10, 1126891415) c = ii(c, d, a, b, x[i + 14], 15, -1416354905) b = ii(b, c, d, a, x[i + 5], 21, -57434055) a = ii(a, b, c, d, x[i + 12], 6, 1700485571) d = ii(d, a, b, c, x[i + 3], 10, -1894986606) c = ii(c, d, a, b, x[i + 10], 15, -1051523) b = ii(b, c, d, a, x[i + 1], 21, -2054922799) a = ii(a, b, c, d, x[i + 8], 6, 1873313359) d = ii(d, a, b, c, x[i + 15], 10, -30611744) c = ii(c, d, a, b, x[i + 6], 15, -1560198380) b = ii(b, c, d, a, x[i + 13], 21, 1309151649) a = ii(a, b, c, d, x[i + 4], 6, -145523070) d = ii(d, a, b, c, x[i + 11], 10, -1120210379) c = ii(c, d, a, b, x[i + 2], 15, 718787259) b = ii(b, c, d, a, x[i + 9], 21, -343485551) a = safe_add(a, olda) b = safe_add(b, oldb) c = safe_add(c, oldc) d = safe_add(d, oldd) } return [a, b, c, d] } /* * Convert an array of little-endian words to a hex string. */ function binl2hex(binarray) { var hex_tab = "0123456789abcdef" var str = "" for (var i = 0; i < binarray.length * 4; i++) { str += hex_tab.charAt((binarray[i >> 2] >> ((i % 4) * 8 + 4)) & 0xF) + hex_tab.charAt((binarray[i >> 2] >> ((i % 4) * 8)) & 0xF) } return str } /* * Convert an array of little-endian words to a base64 encoded string. */ function binl2b64(binarray) { var tab = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/" var str = "" for (var i = 0; i < binarray.length * 32; i += 6) { str += tab.charAt(((binarray[i >> 5] << (i % 32)) & 0x3F) | ((binarray[i >> 5 + 1] >> (32 - i % 32)) & 0x3F)) } return str } /* * Convert an 8-bit character string to a sequence of 16-word blocks, stored * as an array, and append appropriate padding for MD4/5 calculation. * If any of the characters are >255, the high byte is silently ignored. */ function str2binl(str) { var nblk = ((str.length + 8) >> 6) + 1 // number of 16-word blocks var blks = new Array(nblk * 16) for (var i = 0; i < nblk * 16; i++) blks[i] = 0 for (var i = 0; i < str.length; i++) blks[i >> 2] |= (str.charCodeAt(i) & 0xFF) << ((i % 4) * 8) blks[i >> 2] |= 0x80 << ((i % 4) * 8) blks[nblk * 16 - 2] = str.length * 8 return blks } /* * Convert a wide-character string to a sequence of 16-word blocks, stored as * an array, and append appropriate padding for MD4/5 calculation. */ function strw2binl(str) { var nblk = ((str.length + 4) >> 5) + 1 // number of 16-word blocks var blks = new Array(nblk * 16) for (var i = 0; i < nblk * 16; i++) blks[i] = 0 for (var i = 0; i < str.length; i++) blks[i >> 1] |= str.charCodeAt(i) << ((i % 2) * 16) blks[i >> 1] |= 0x80 << ((i % 2) * 16) blks[nblk * 16 - 2] = str.length * 16 return blks } /* * External interface */ function hexMD5(str) { return binl2hex(coreMD5(str2binl(str))) } function hexMD5w(str) { return binl2hex(coreMD5(strw2binl(str))) } function b64MD5(str) { return binl2b64(coreMD5(str2binl(str))) } function b64MD5w(str) { return binl2b64(coreMD5(strw2binl(str))) } /* Backward compatibility */ function calcMD5(str) { return binl2hex(coreMD5(str2binl(str))) } module.exports = { hexMD5: hexMD5 }
在使用的过程中,正常的数字以及字母参数都没有出现问题,当涉及的业务需要传递值为中文字符串的参数时,会出现签名错误的问题,即前端和后端在同参数下生成的签名不一样。
一开始我通过将字符串进行url转译后再传给后台的方法来保证签名一致,不过当要后台根据参数插入数据的时候,发现插入的字符串都是url编码,于是我又开始从源头寻找问题的解决办法。
最开始的时候我以为是微信js的编码默认不是utf-8,实际通过对字符串url转译发现和在线utf-8转url的编码是一样的,而且时候也想到,如果编码格式和后台不一样,那么前端转译成的url编码在后台解码后生成的字符肯定是乱码,这才让我想到是md5加密代码的问题。而后,在百度上又寻找了一份优化后的md5加密代码,使用后发现完美解决了当前问题。
以下代码适用于微信小程序中对中文字符串进行md5加密
var rotateLeft = function (lValue, iShiftBits) { return (lValue << iShiftBits) | (lValue >>> (32 - iShiftBits)); } var addUnsigned = function (lX, lY) { var lX4, lY4, lX8, lY8, lResult; lX8 = (lX & 0x80000000); lY8 = (lY & 0x80000000); lX4 = (lX & 0x40000000); lY4 = (lY & 0x40000000); lResult = (lX & 0x3FFFFFFF) + (lY & 0x3FFFFFFF); if (lX4 & lY4) return (lResult ^ 0x80000000 ^ lX8 ^ lY8); if (lX4 | lY4) { if (lResult & 0x40000000) return (lResult ^ 0xC0000000 ^ lX8 ^ lY8); else return (lResult ^ 0x40000000 ^ lX8 ^ lY8); } else { return (lResult ^ lX8 ^ lY8); } } var F = function (x, y, z) { return (x & y) | ((~x) & z); } var G = function (x, y, z) { return (x & z) | (y & (~z)); } var H = function (x, y, z) { return (x ^ y ^ z); } var I = function (x, y, z) { return (y ^ (x | (~z))); } var FF = function (a, b, c, d, x, s, ac) { a = addUnsigned(a, addUnsigned(addUnsigned(F(b, c, d), x), ac)); return addUnsigned(rotateLeft(a, s), b); }; var GG = function (a, b, c, d, x, s, ac) { a = addUnsigned(a, addUnsigned(addUnsigned(G(b, c, d), x), ac)); return addUnsigned(rotateLeft(a, s), b); }; var HH = function (a, b, c, d, x, s, ac) { a = addUnsigned(a, addUnsigned(addUnsigned(H(b, c, d), x), ac)); return addUnsigned(rotateLeft(a, s), b); }; var II = function (a, b, c, d, x, s, ac) { a = addUnsigned(a, addUnsigned(addUnsigned(I(b, c, d), x), ac)); return addUnsigned(rotateLeft(a, s), b); }; var convertToWordArray = function (string) { var lWordCount; var lMessageLength = string.length; var lNumberOfWordsTempOne = lMessageLength + 8; var lNumberOfWordsTempTwo = (lNumberOfWordsTempOne - (lNumberOfWordsTempOne % 64)) / 64; var lNumberOfWords = (lNumberOfWordsTempTwo + 1) * 16; var lWordArray = Array(lNumberOfWords - 1); var lBytePosition = 0; var lByteCount = 0; while (lByteCount < lMessageLength) { lWordCount = (lByteCount - (lByteCount % 4)) / 4; lBytePosition = (lByteCount % 4) * 8; lWordArray[lWordCount] = (lWordArray[lWordCount] | (string.charCodeAt(lByteCount) << lBytePosition)); lByteCount++; } lWordCount = (lByteCount - (lByteCount % 4)) / 4; lBytePosition = (lByteCount % 4) * 8; lWordArray[lWordCount] = lWordArray[lWordCount] | (0x80 << lBytePosition); lWordArray[lNumberOfWords - 2] = lMessageLength << 3; lWordArray[lNumberOfWords - 1] = lMessageLength >>> 29; return lWordArray; }; var wordToHex = function (lValue) { var WordToHexValue = "", WordToHexValueTemp = "", lByte, lCount; for (lCount = 0; lCount <= 3; lCount++) { lByte = (lValue >>> (lCount * 8)) & 255; WordToHexValueTemp = "0" + lByte.toString(16); WordToHexValue = WordToHexValue + WordToHexValueTemp.substr(WordToHexValueTemp.length - 2, 2); } return WordToHexValue; }; var uTF8Encode = function (string) { string = string.replace(/\x0d\x0a/g, "\x0a"); var output = ""; for (var n = 0; n < string.length; n++) { var c = string.charCodeAt(n); if (c < 128) { output += String.fromCharCode(c); } else if ((c > 127) && (c < 2048)) { output += String.fromCharCode((c >> 6) | 192); output += String.fromCharCode((c & 63) | 128); } else { output += String.fromCharCode((c >> 12) | 224); output += String.fromCharCode(((c >> 6) & 63) | 128); output += String.fromCharCode((c & 63) | 128); } } return output; }; function md5(string) { var x = Array(); var k, AA, BB, CC, DD, a, b, c, d; var S11 = 7, S12 = 12, S13 = 17, S14 = 22; var S21 = 5, S22 = 9, S23 = 14, S24 = 20; var S31 = 4, S32 = 11, S33 = 16, S34 = 23; var S41 = 6, S42 = 10, S43 = 15, S44 = 21; string = uTF8Encode(string); x = convertToWordArray(string); a = 0x67452301; b = 0xEFCDAB89; c = 0x98BADCFE; d = 0x10325476; for (k = 0; k < x.length; k += 16) { AA = a; BB = b; CC = c; DD = d; a = FF(a, b, c, d, x[k + 0], S11, 0xD76AA478); d = FF(d, a, b, c, x[k + 1], S12, 0xE8C7B756); c = FF(c, d, a, b, x[k + 2], S13, 0x242070DB); b = FF(b, c, d, a, x[k + 3], S14, 0xC1BDCEEE); a = FF(a, b, c, d, x[k + 4], S11, 0xF57C0FAF); d = FF(d, a, b, c, x[k + 5], S12, 0x4787C62A); c = FF(c, d, a, b, x[k + 6], S13, 0xA8304613); b = FF(b, c, d, a, x[k + 7], S14, 0xFD469501); a = FF(a, b, c, d, x[k + 8], S11, 0x698098D8); d = FF(d, a, b, c, x[k + 9], S12, 0x8B44F7AF); c = FF(c, d, a, b, x[k + 10], S13, 0xFFFF5BB1); b = FF(b, c, d, a, x[k + 11], S14, 0x895CD7BE); a = FF(a, b, c, d, x[k + 12], S11, 0x6B901122); d = FF(d, a, b, c, x[k + 13], S12, 0xFD987193); c = FF(c, d, a, b, x[k + 14], S13, 0xA679438E); b = FF(b, c, d, a, x[k + 15], S14, 0x49B40821); a = GG(a, b, c, d, x[k + 1], S21, 0xF61E2562); d = GG(d, a, b, c, x[k + 6], S22, 0xC040B340); c = GG(c, d, a, b, x[k + 11], S23, 0x265E5A51); b = GG(b, c, d, a, x[k + 0], S24, 0xE9B6C7AA); a = GG(a, b, c, d, x[k + 5], S21, 0xD62F105D); d = GG(d, a, b, c, x[k + 10], S22, 0x2441453); c = GG(c, d, a, b, x[k + 15], S23, 0xD8A1E681); b = GG(b, c, d, a, x[k + 4], S24, 0xE7D3FBC8); a = GG(a, b, c, d, x[k + 9], S21, 0x21E1CDE6); d = GG(d, a, b, c, x[k + 14], S22, 0xC33707D6); c = GG(c, d, a, b, x[k + 3], S23, 0xF4D50D87); b = GG(b, c, d, a, x[k + 8], S24, 0x455A14ED); a = GG(a, b, c, d, x[k + 13], S21, 0xA9E3E905); d = GG(d, a, b, c, x[k + 2], S22, 0xFCEFA3F8); c = GG(c, d, a, b, x[k + 7], S23, 0x676F02D9); b = GG(b, c, d, a, x[k + 12], S24, 0x8D2A4C8A); a = HH(a, b, c, d, x[k + 5], S31, 0xFFFA3942); d = HH(d, a, b, c, x[k + 8], S32, 0x8771F681); c = HH(c, d, a, b, x[k + 11], S33, 0x6D9D6122); b = HH(b, c, d, a, x[k + 14], S34, 0xFDE5380C); a = HH(a, b, c, d, x[k + 1], S31, 0xA4BEEA44); d = HH(d, a, b, c, x[k + 4], S32, 0x4BDECFA9); c = HH(c, d, a, b, x[k + 7], S33, 0xF6BB4B60); b = HH(b, c, d, a, x[k + 10], S34, 0xBEBFBC70); a = HH(a, b, c, d, x[k + 13], S31, 0x289B7EC6); d = HH(d, a, b, c, x[k + 0], S32, 0xEAA127FA); c = HH(c, d, a, b, x[k + 3], S33, 0xD4EF3085); b = HH(b, c, d, a, x[k + 6], S34, 0x4881D05); a = HH(a, b, c, d, x[k + 9], S31, 0xD9D4D039); d = HH(d, a, b, c, x[k + 12], S32, 0xE6DB99E5); c = HH(c, d, a, b, x[k + 15], S33, 0x1FA27CF8); b = HH(b, c, d, a, x[k + 2], S34, 0xC4AC5665); a = II(a, b, c, d, x[k + 0], S41, 0xF4292244); d = II(d, a, b, c, x[k + 7], S42, 0x432AFF97); c = II(c, d, a, b, x[k + 14], S43, 0xAB9423A7); b = II(b, c, d, a, x[k + 5], S44, 0xFC93A039); a = II(a, b, c, d, x[k + 12], S41, 0x655B59C3); d = II(d, a, b, c, x[k + 3], S42, 0x8F0CCC92); c = II(c, d, a, b, x[k + 10], S43, 0xFFEFF47D); b = II(b, c, d, a, x[k + 1], S44, 0x85845DD1); a = II(a, b, c, d, x[k + 8], S41, 0x6FA87E4F); d = II(d, a, b, c, x[k + 15], S42, 0xFE2CE6E0); c = II(c, d, a, b, x[k + 6], S43, 0xA3014314); b = II(b, c, d, a, x[k + 13], S44, 0x4E0811A1); a = II(a, b, c, d, x[k + 4], S41, 0xF7537E82); d = II(d, a, b, c, x[k + 11], S42, 0xBD3AF235); c = II(c, d, a, b, x[k + 2], S43, 0x2AD7D2BB); b = II(b, c, d, a, x[k + 9], S44, 0xEB86D391); a = addUnsigned(a, AA); b = addUnsigned(b, BB); c = addUnsigned(c, CC); d = addUnsigned(d, DD); } var tempValue = wordToHex(a) + wordToHex(b) + wordToHex(c) + wordToHex(d); return tempValue.toLowerCase(); } module.exports.md5 = md5