{"id":433,"date":"2020-12-13T00:28:22","date_gmt":"2020-12-12T16:28:22","guid":{"rendered":"http:\/\/moyisuiying.com\/?p=433"},"modified":"2020-12-13T00:28:22","modified_gmt":"2020-12-12T16:28:22","slug":"%e4%bf%a1%e6%81%af%e6%91%98%e8%a6%81%e5%87%bd%e6%95%b0hash%e5%87%bd%e6%95%b0%e7%9a%84%e8%ae%be%e8%ae%a1%e4%b8%8e%e6%80%a7%e8%b4%a8%e9%aa%8c%e8%af%81","status":"publish","type":"post","link":"http:\/\/moyisuiying.com\/index.php\/cppstudy\/information-secure\/433.html","title":{"rendered":"\u4fe1\u606f\u6458\u8981\u51fd\u6570(Hash\u51fd\u6570)\u7684\u8bbe\u8ba1\u4e0e\u6027\u8d28\u9a8c\u8bc1"},"content":{"rendered":"\n

1.\u4fe1\u606f\u6458\u8981\u51fd\u6570(Hash\u51fd\u6570)\u7684\u8bbe\u8ba1\u4e0e\u6027\u8d28\u9a8c\u8bc1\u5b9e\u9a8c<\/h2>\n\n\n\n

2.\u5b9e\u9a8c\u76ee\u7684\uff1a\u4fe1\u606f\u6458\u8981\u51fd\u6570(Hash\u51fd\u6570)\u7684\u8bbe\u8ba1\u4e0e\u6027\u8d28\u9a8c\u8bc1\u3002<\/h2>\n\n\n\n

2.1\u5b9e\u9a8c\u8bbe\u5907\uff1aPC\u673a \u4e00\u53f0\/\u4eba<\/h3>\n\n\n\n

2.2\u5b9e\u9a8c\u539f\u7406\uff1a<\/h3>\n\n\n\n

2.2.1.\u4fe1\u606f\u6458\u8981\u51fd\u6570\u5177\u6709\u56fa\u5b9a\u7684\u8f93\u51fa\u6570\u4f4d\u3002<\/h4>\n\n\n\n

2.2.1\u4fe1\u606f\u6458\u8981\u51fd\u6570\u6ee1\u8db3\u4e0d\u53ef\u6c42\u9006\uff0c\u4e0d\u53ef\u4f2a\u9020\u548c\u5728\u53ef\u884c\u65f6\u95f4\u4e4b\u5185\u627e\u4e0d\u5230\u78b0\u649e\u7b49\u7279\u6027\u3002<\/h4>\n\n\n\n

3.\u5b9e\u9a8c\u5185\u5bb9\u53ca\u6ce8\u610f\u4e8b\u9879\uff1a<\/h2>\n\n\n\n

\u4fe1\u606f\u6458\u8981\u51fd\u6570\u7684\u8bbe\u8ba1\u4e0eHash\u503c\u7684\u6027\u8d28\u9a8c\u8bc1<\/p>\n\n\n\n

\u5b9e\u9a8c\u6b65\u9aa4\uff1a<\/p>\n\n\n\n

3.1\u8bbe\u8ba1\u7b26\u5408\u539f\u7406\u8981\u6c42\u7684\u4fe1\u606f\u6458\u8981\u51fd\u6570H(m)\u3002<\/h3>\n\n\n\n

3.2\u5bf9\u4e8e\u5982\u4e0b\u660e\u6587\u4fe1\u606fm:<\/h3>\n\n\n\n
There was a grocery shop in a town. Plenty of mice lived in that grocery shop. Food was in plenty for them. They ate everything and spoiled all the bags. They also wasted the bread, biscuits and fruits of the shop. The grocer got really worried. So, he thought \"I should buy a cat and let it stay at the grocery. Only then I can save my things.\" He bought a nice, big fat cat and let him stay there. The cat had a nice time hunting the mice and killing them. The mice could not move freely now. They were afraid that anytime the cat would eat them up. The mice wanted to do something. They held a meeting and all of them tweeted \"We must get rid of the cat. Can someone give a suggestion\"?  All the mice sat and brooded. A smart looking mouse stood up and said, \"The cat moves softly. That is the problem. If we can tie a bell around her neck, then things will be fine. We can know the movements of the cat\". \u201cYes, that is answer,\" stated all the mice. An old mouse slowly stood up and asked, \"Who would tie the bell?\" After some moments there was no one there to answer this question. <\/code><\/pre>\n\n\n\n
\u8c03\u7528H(m)\u7b97\u6cd5\uff0c\u4ea7\u751fHash\u503c\u3002<\/p>\n\n\n\n
3.3\u968f\u673a\u6539\u53d8m\u7684\u4efb\u610f\u4e00\u4f4d\u5b57\u7b26\uff0c\u4ea7\u751f\u65b0\u7684Hash\u503c\uff0c<\/h3>\n\n\n\n
\u5982\u6b64\u5b9e\u9a8c10\u6b21\uff0c\u8bb0\u65b0\u7684Hash\u503c\u4e3a H1,H2,\u2026H10<\/p>\n\n\n\n
3.4\u8bbe\u8ba1\u51fd\u6570\u8ba1\u7b97H0\u548cHi \u7684\u76f8\u4f3c\u5ea6 i=1,2,\u202610<\/h3>\n\n\n\n
3.5\u5206\u6790\u7ed3\u679c\uff0c\u5f97\u51fa\u7ed3\u8bba<\/h3>\n\n\n\n
4.\u5b9e\u9a8c\u8fc7\u7a0b<\/h2>\n\n\n\n
4.1\u8bbe\u8ba1 \u54c8\u5e0c\u51fd\u6570Hash(m)\u7684\u601d\u8def<\/h3>\n\n\n\n
\u200b MD5<\/strong>\u6458\u8981\u7b97\u6cd5\u662fHash\u6458\u8981\u7b97\u6cd5\u4e2d\u7684\u4e00\u79cd\u6458\u8981\u7b97\u6cd5\uff0c\u5177\u6709\u4e0d\u53ef\u6c42\u9006\u6027\uff0c\u4e0d\u53ef\u4f2a\u9020\u6027<\/strong>\u3002MD5 \u7b97\u6cd5\u81ea\u8bde\u751f\u4e4b\u65e5\u8d77\uff0c\u5c31\u6709\u5f88\u591a\u4eba\u8bd5\u56fe\u8bc1\u660e\u548c\u53d1\u73b0\u5b83\u7684\u4e0d\u5b89\u5168\u4e4b\u5904\uff0c\u5373\u5b58\u5728\u78b0\u649e\uff08\u5728\u5bf9\u4e24\u4e2a\u4e0d\u540c\u7684\u5185\u5bb9\u4f7f\u7528 MD5\u7b97\u6cd5\u8fd0\u7b97\u7684\u65f6\u5019\uff0c\u6709\u53ef\u80fd\u5f97\u5230\u4e00\u5bf9\u76f8\u540c\u7684\u7ed3\u679c\u503c\uff09\u30022009\u5e74\uff0c\u4e2d\u56fd\u79d1\u5b66\u9662\u7684\u8c22\u6d9b\u548c\u51af\u767b\u56fd\u4ec5\u7528\u4e86 \u7684\u78b0\u649e\u7b97\u6cd5\u590d\u6742\u5ea6\uff0c\u7834\u89e3\u4e86MD5\u7684\u78b0\u649e\u62b5\u6297\uff0c\u8be5\u653b\u51fb\u5728\u666e\u901a\u8ba1\u7b97\u673a\u4e0a\u8fd0\u884c\u53ea\u9700\u8981\u6570\u79d2\u949f \u3002\u56e0\u6b64MD5\u7b97\u6cd5\u4e0d\u5177\u5907\u5b9e\u9a8c\u4e2d\u8981\u6c42\u7684\u201c\u5728\u53ef\u884c\u65f6\u95f4\u4e4b\u5185\u627e\u4e0d\u5230\u78b0\u649e\u201d\u8fd9\u4e2a\u7279\u6027\u3002
\u200b \u6839\u636eMD5\u7684\u5b58\u5728\u7684\u7f3a\u70b9\uff0c\u4e3a\u4e86\u52a0\u5f3aMD5\u52a0\u5bc6\u7b97\u6cd5\u7684\u5b89\u5168\u6027\uff08\u672c\u8eab\u662f\u4e0d\u53ef\u9006\u7684\uff09\uff0c\u4ece\u800c\u52a0\u5165\u4e86\u65b0\u7684\u7b97\u6cd5\u90e8\u5206\u5373\u52a0\u76d0\u503c\uff0c\u52a0\u76d0\u503c\u662f\u968f\u673a\u751f\u6210\u7684\u4e00\u7ec4\u5b57\u7b26\u4e32\uff0c\u53ef\u4ee5\u5305\u62ec\u968f\u673a\u7684\u5927\u5c0f\u5199\u5b57\u6bcd\u3001\u6570\u5b57\u3001\u5b57\u7b26\uff0c\u4f4d\u6570\u53ef\u4ee5\u6839\u636e\u8981\u6c42\u800c\u4e0d\u4e00\u6837\uff0c\u4f7f\u7528\u4e0d\u540c\u7684\u52a0\u76d0\u503c\u4ea7\u751f\u7684\u6700\u7ec8\u5bc6\u6587\u662f\u4e0d\u4e00\u6837\u7684\u3002\u7531\u4e8e\u4f7f\u7528\u52a0\u76d0\u503c\u4ee5\u540e\u7684\u5bc6\u7801\u76f8\u5f53\u7684\u5b89\u5168\uff0c\u5373\u4fbf\u662f\u4f60\u83b7\u5f97\u4e86\u5176\u4e2d\u7684salt\u548c\u6700\u7ec8\u5bc6\u6587\uff0c\u7834\u89e3\u4e5f\u662f\u4e00\u4e2a\u8017\u8d39\u76f8\u5f53\u591a\u65f6\u95f4\u7684\u8fc7\u7a0b\uff0c\u53ef\u4ee5\u8bf4\u662f\u7834\u89e3\u5355\u7eafMD5\u7684\u597d\u51e0\u500d\u3002\u5e76\u4e14\u540c\u4e00\u4e2a\u660e\u6587\u5728\u7ecf\u8fc7\u52a0\u76d0\uff08\u8fd9\u4e2a\u76d0\u662f\u968f\u673a\u7684\uff0c\u4e0d\u540c\u7684\uff09\u540e\u8fdb\u884cMD5\u7b97\u6cd5\u4ea7\u751f\u7684\u5bc6\u6587\u4e5f\u662f\u4e0d\u540c\u7684\u3002\u8fd9\u5c31\u4f7f\u5f97MD5\u7b97\u6cd5\u7684\u6297\u78b0\u649e\u6027\u5f97\u5230\u5927\u5e45\u5ea6\u589e\u5f3a\uff0c\u56e0\u6b64\u53ef\u4ee5\u6ee1\u8db3\u672c\u6b21\u5b9e\u9a8c\u8981\u6c42\u3002<\/p>\n\n\n\n
4.2MD5+\u76d0\u7684\u5b9e\u73b0\u6b65\u9aa4<\/h3>\n\n\n\n
1).\u9996\u5148\u83b7\u53d6\u9700\u8981\u8fdb\u884cmd5\u666e\u6458\u8981\u7b97\u6cd5\u7684\u660e\u6587text\u3002
2).\u968f\u673a\u751f\u6210\u52a0\u76d0\u503c\uff08\u53ef\u4ee5\u7531\u5b57\u6bcd\uff0c\u6570\u5b57\uff0c\u5b57\u7b26\u7ec4\u6210\uff0c\u4f4d\u6570\u53ef\u4ee5\u81ea\u5df1\u51b3\u5b9a\uff0c\u8fd9\u91cc\u4f7f\u752816\u4f4d\u7684\u5b57\u7b26\u4e32\uff09salt\u5b57\u7b26\u4e32.
3)\u5c06\u751f\u6210\u7684salt\u5b57\u7b26\u4e32\u8ffd\u52a0\u5230\u660e\u6587text\u4e2d\uff0c\u5f97\u5230\u7ec4\u5408\u7684\u5b57\u7b26\u4e32 mergeText = text +salt
4\uff09\u4f7f\u7528md5\u666e\u901a\u6458\u8981\u7b97\u6cd5\u83b7\u53d6mergeText \u7684hash\u503c\u5f97\u5230\u4e00\u4e2a32\u4f4d\u7684\u5b57\u7b26\u4e32decodeText\u3002
5).\u5c06\u76d0salt\u5b57\u7b26\u4e32\u7684\u6bcf\u4e2a\u5b57\u7b26\u9010\u4e2a\u63d2\u5165\u5230\u5b57\u7b26\u4e32decodeText\u662f i *3+1\uff08i = 0,1,2,\u202616\uff09\u7684\u4f4d\u7f6e\u4e0a,\u5f97\u5230\u4e00\u4e2a\u65b0\u768448\u4f4d\u7684\u5b57\u7b26\u4e32 decode\u3002
6\uff09\u6700\u7ec8\u7684decode\u5b57\u7b26\u4e32\u5c31\u662f\u6240\u8981\u7684\u5bc6\u6587\uff0c\u4f4d\u957f\u4e3a48\u4e2a\u5b57\u7b26\u3002<\/p>\n\n\n\n
\u8be5\u4ee3\u7801\u5df2\u7ecf\u7528c++\u5b9e\u73b0\uff0c\u5177\u4f53\u8bf7\u770b\uff1aC++<\/a>\u5b9e\u73b0MD5\u6458\u8981\u7b97\u6cd5\u52a0\u76d0salt\u503c<\/a><\/p>\n\n\n\n
4.3\u5177\u4f53\u4ee3\u7801\u5b9e\u73b0<\/h3>\n\n\n\n
4.3.1MD5\u7684\u666e\u901a\u52a0\u5bc6\u7b97\u6cd5<\/h4>\n\n\n\n
4.3.1.1.\u5c06\u4e8c\u8fdb\u5236\u5b57\u8282\u6570\u7ec4\u8f6c\u6362\u4e3a16\u8fdb\u5236\u7684\u5b57\u7b26\u4e32<\/h5>\n\n\n\n
\/* Convert byte array to hex string. *\/\nstring MD5::bytesToHexString(const byte *input, size_t length) {\n    string str;\n    str.reserve(length << 1);\n    for (size_t i = 0; i < length; i++) {\n        int t = input[i];\n        int a = t \/ 16;\n        int b = t % 16;\n        str.append(1, HEX[a]);\n        str.append(1, HEX[b]);\n    }\n    return str;\n}<\/code><\/pre>\n\n\n\n
string EncryptUtil::md5Hex(const string& text) {\n    \/\/\u9996\u5148\u66f4\u65b0md5\u4e2d\u9700\u8981\u8fdb\u884c\u6458\u8981\u7684\u5b57\u7b26\u4e32\n    this->md5->update(text);\n    \/\/\u4f7f\u7528md5\u7684\u65b9\u6cd5\u751f\u6210\u5bf9\u5e94\u7684\u6458\u8981\u540e\u7684\u5b57\u7b26\u4e32\n    return this->md5->toString();\n\n}<\/code><\/pre>\n\n\n\n
4.3.2\u4ea7\u751f\u76d0\u503c\u5b57\u7b26\u4e32\u7684\u7b97\u6cd5<\/h4>\n\n\n\n
\/**\n\u4ea7\u751f\u76d0\u503c\u5b57\u7b26\u4e32salt\n*\/\nstring EncryptUtil::createSalt()\n{\n    \/\/\u968f\u673a\u751f\u6210\u4e24\u4e2a\u968f\u673a\u6570\n    int num1 = rand() % 99999999;\n    int num2 = rand() % 99999999;\n    string salt = \"\";\n    \/\/\u5c06\u8fd9\u4e24\u4e2a\u968f\u673a\u6570\u8f6c\u6362\u4e3a\u5b57\u7b26\u4e32\u540e\u8ffd\u52a0\u5230salt\u4e2d\n    salt.append(to_string(num1));\n    salt.append(to_string(num2));\n    \/\/salt\u4e0d\u591f\u5341\u516d\u4f4d\u5c31\u5728\u540e\u9762\u52a00\n    int len = salt.size();\n    if (len < 16) {\n        for (int i = 0; i < 16 - len; i++) {\n            salt.append(\"0\");\n        }\n    }\n    return salt;\n}<\/code><\/pre>\n\n\n\n
4.3.3\u83b7\u53d6md5\u666e\u901a\u6458\u8981\u51fd\u6570+\u76d0\u503csalt\u64cd\u4f5c\u540e\u7684\u6700\u7ec8\u5bc6\u6587<\/h4>\n\n\n\n
\/**\n* \u52a0\u76d0MD5\n* @param text : \u9700\u8981\u8fdb\u884c\u52a0\u76d0\u540e\u6458\u8981\u7684text\u660e\u6587\n* @return string\uff1a\u8fd4\u56de\u8fdb\u884c\u6458\u8981\u7b97\u6cd5\u540e\u7684\u5b57\u7b26\u4e32\n*\/\nstring EncryptUtil::encryptBySalt(const string& text) {\n    \/\/\u4ea7\u751f\u76d0\u503c\u5b57\u7b26\u4e32salt\n    string salt = createSalt();\n    \/\/\u5c06\u4ea7\u751f\u7684salt\u8ffd\u52a0\u5230\u9700\u8981\u8fdb\u884c\u6458\u8981\u7684\u660e\u6587text\u4e2d\uff0c\u5f97\u5230\u7531\u660e\u6587text\u548csalt\u7ec4\u6210\u7684\u5b57\u7b26\u4e32\n    string merge_str =  text + salt;\n    \/\/\u4f7f\u7528md5\u7b97\u6cd5\u8fdb\u884c\u6458\u8981\u8ba1\u7b97\u5f97\u5230\u76f8\u5e94\u768432\u4f4d\u7684\u5bc6\u6587\n    string encodeText = md5Hex(merge_str);\n    char cs [48];\n    \/\/\u5c0632\u4f4d\u7684\u5bc6\u6587\u548c\u4ea7\u751f\u768416\u4f4d\u7684salt\u8fdb\u884c\u91cd\u7ec4\u5f62\u6210\u65b0\u768448\u4f4d\u7684\u5b57\u7b26\u4e32\u3002\n    \/\/\u8fd9\u91cc\u8868\u793a\uff0c\u5728\u65b0\u7684\u5b57\u7b26\u6570\u7ec4cs\u4e2d\uff0csalt\u4e2d\u7684\u5b57\u7b26\u6dfb\u52a0\u5230cs\u5b57\u7b26\u6570\u7ec4\u4e2d\u4f4d\u7f6e\u662fi*3+1\u7684\u4f4d\u7f6e\uff0c\u5176\u5b83\u4f4d\u7f6e\u7531\u6458\u8981\u5bc6\u6587encodeText\u4e2d\u7684\u5b57\u7b26\u586b\u5145\n    for (int i = 0; i < 48; i += 3) {\n        cs[i] = encodeText[i \/ 3 * 2];\n        char c = salt[i \/ 3];\n        cs[i + 1] = c;\n        cs[i + 2] = encodeText[i \/ 3 * 2 + 1];\n    }\n    \/\/\u5c06\u7ec4\u5408\u6210\u7684cs\u5b57\u7b26\u6570\u7ec4\u8f6c\u5316\u4e3a\u5b57\u7b26\u4e32\u5f97\u523048\u4f4d\u7684\u52a0\u76d0\u540e\u5f62\u6210\u7684md5\u6458\u8981\u5bc6\u6587\n    string code = \"\";\n    for (int i = 0; i < 48; i++)\n    {\n      code.append(1,cs[i]);\n    }\n    return code;\n}<\/code><\/pre>\n\n\n\n
4.3.4\u6821\u9a8c\u52a0\u76d0\u540e\u662f\u5426\u548c\u539f\u6587\u4e00\u81f4<\/h4>\n\n\n\n
\/**\n * \u6821\u9a8c\u52a0\u76d0\u540e\u662f\u5426\u548c\u539f\u6587\u4e00\u81f4\n * @param text : \u8fdb\u884c\u6458\u8981\u7b97\u6cd5\u7684\u660e\u6587\n * @param encryptText  \uff1a \u8fdb\u884c\u52a0\u76d0\u6458\u8981\u7b97\u6cd5\u540e\u7684\u5bc6\u6587\n * @return \u5982\u679c\u52a0\u76d0\u540e\u548c\u539f\u660e\u6587text\u4e00\u81f4\u5219\u8fd4\u56detrue\uff0c\u5426\u5219\u8fd4\u56defalse\n *\/\n bool EncryptUtil::verify( string text,  string encryptText) {\n    char md5Text[32];\n    char salt[16];\n    \/\/\u9996\u5148\u5c06\u52a0\u76d0\u540emd5\u7b97\u6cd5\u6458\u8981\u5f97\u5230\u7684encryptText\u5bc6\u6587\u8fdb\u884c\u62c6\u5206\u6210\u4e00\u4e2a32\u4f4d\u7684\u666e\u901amd5\u6458\u8981\u7b97\u6cd5\u5bc6\u6587md5Text\u548c\u4e00\u4e2a16\u4f4d\u7684\u5b57\u7b26\u4e32salt\u3002\n    \/\/\u8fd9\u91cc\u5c31\u662f\u8fdb\u884csalt\u548cmd5\u6458\u8981\u5bc6\u6587\u5f62\u621048\u4f4d\u65b0\u7684\u5b57\u7b26\u4e32encryptText\u65f6\u7684\u9006\u5411\u64cd\u4f5c\u3002encryptText\u4e2dsalt[i] =  encryptText[ 3* i + 1], i = 0,1,2,...16\n    for (int i = 0; i < 48; i += 3) {\n        md5Text[i \/ 3 * 2] = encryptText[i];\n        md5Text[i \/ 3 * 2 + 1] = encryptText[i + 2];\n        salt[i \/ 3] = encryptText[i + 1];\n    }\n    \/\/\u5c06\u62c6\u5206\u768416\u4e2a\u968f\u673a\u5b57\u7b26\u4e32\u8ffdsalt\u52a0\u5230\u660e\u6587text\u4e2d\n    for (int  i = 0; i < 16; i++)\n    {\n        text.append(1,salt[i]);\n    }\n    \/\/\u4f7f\u7528md5\u6458\u8981\u7b97\u6cd5\u8fdb\u884c\u751f\u6210\u5bc6\u6587\u5f97\u5230enCs2\n    string enCs2 = md5Hex(text);\n    \/\/\u6bd4\u8f83\u4e24\u4e2a\u5b57\u7b26\u4e32\u76f8\u7b49\uff0c\u5982\u679c\u76f8\u7b49\u5219\u8fd4\u56detrue\uff0c\u53ea\u8981\u6709\u4e00\u4e2a\u5b57\u7b26\u4e0d\u76f8\u7b49\u5c31\u8fd4\u56defalse\n    for (int i = 0; i < enCs2.size(); i++)\n    {\n        if (enCs2[i] != md5Text[i])\n        {\n            return false;\n        }\n    }\n    return true;\n}<\/code><\/pre>\n\n\n\n
4.3.5 \u9010\u4e2a\u6bd4\u8f83\u4e24\u4e2a\u5bc6\u6587\u76f8\u540c\u4f4d\u7f6e\u4e0a\u5b57\u7b26\u662f\u5426\u76f8\u540c\u6765\u8ba1\u7b97\u4e24\u4e2a\u660e\u6587\u8fdb\u884cmd5\u52a0\u5bc6\u540e\u7684\u76f8\u4f3c\u5ea6\u3002<\/h4>\n\n\n\n
\/**\n  \u9010\u4e2a\u6bd4\u8f83\u4e24\u4e2a\u5bc6\u6587\u76f8\u540c\u4f4d\u7f6e\u4e0a\u5b57\u7b26\u662f\u5426\u76f8\u540c\u6765\u8ba1\u7b97\u4e24\u4e2a\u660e\u6587\u8fdb\u884cmd5\u52a0\u5bc6\u540e\u7684\u76f8\u4f3c\u5ea6\u3002\n @param str1: md5\u6458\u8981\u7b97\u6cd5\u540e\u7684\u5b57\u7b26\u4e32\n @param str2:md5\u6458\u8981\u7b97\u6cd5\u540e\u7684\u5b57\u7b26\u4e32\n @return double: \u8fd4\u56de\u76f8\u4f3c\u5ea6\n *\/\ndouble EncryptUtil::similarityDegree(const string& str1, const string& str2)\n{\n    if (str1.size() <= 0 && (str1.size() != str2.size()))\n    {\n        return 0;\n    }\n    int count = 0;\n    \/\/\u7edf\u8ba1\u5bf9\u5e94\u4f4d\u7f6e\u4e0a\u5b57\u7b26\u76f8\u540c\u7684\u4e2a\u6570\n    for (int i = 0; i < str1.size(); i++)\n    {\n        if (str1[i] == str2[i])\n        {\n            count++;\n        }\n    }\n    \/\/\u8ba1\u7b97\u76f8\u4f3c\u5ea6\n    double result = count * 1.0 \/ str1.size();\n    return result;\n}<\/code><\/pre>\n\n\n\n
4.3.6\u4e3a\u4e86\u65b9\u4fbf\uff0c\u5c06\u660e\u6587\u4fdd\u5b58\u5230\u6587\u4ef6\u4e2d\uff0c\u7136\u540e\u8bfb\u53d6\u6587\u4ef6\u5185\u5bb9\u4f5c\u4e3a\u5b57\u7b26\u4e32<\/h4>\n\n\n\n
string loadTextToString(const string textFilePath) {\n    ifstream* ism = new ifstream(textFilePath,ios::app|ios::binary);\n    if (ism->is_open())\n    {\n        string text = \"\";\n        char ch;\n        while (!ism->eof())\n        {\n            ism->get(ch);\n            text.append(1,ch);\n        }\n        return text;\n    }\n    else {\n        cout << \"\u6253\u5f00\u6587\u4ef6\u5931\u8d25!\" << endl;\n        return \"\";\n    }\n}<\/code><\/pre>\n\n\n\n
5.\u9a8c\u8bc1\u5b9e\u9a8c\u5185\u5bb9<\/h2>\n\n\n\n
\u8bbe\u8ba1\u51fd\u6570\u9a8c\u8bc1\u83b7\u53d6H0\u5230H10\u7684\u5bc6\u6587\uff0c\u5e76\u8ba1\u7b97\u76f8\u4f3c\u5ea6\u3002<\/p>\n\n\n\n
string randomReplace(string text,int index,string replaceChar) {\n    return text.replace(index,1,replaceChar);\n}\nvoid test() {\n    string text = loadTextToString(\"hashtext.txt\");\n    cout << \"\u9700\u8981\u52a0\u5bc6\u7684\u660e\u6587\u4e3a\uff1a\\n\" << text << endl;\n    EncryptUtil util;\n    string md0 = util.encryptBySalt(text);\n    cout << \"md5\u52a0\u76d0\u540e\u52a0\u5bc6\u7684md5\u503cH0:\" + md0 << endl;\n    vector<string> vec;\n    for (int i = 0; i < 10; i++)\n    {\n        \/\/\u66ff\u6362\u5341\u4e2a\u5b57\u7b26\uff0c\u6bcf\u4e2a\u539f\u6765\u7684\u5b57\u7b26+1\n        string  newStr =    randomReplace(text, i * 5,string(1, text[i * 5] + 1));\n        \/\/\u8ba1\u7b97\u6bcf\u4e2a\u66ff\u6362\u540e\u5b57\u7b26\u7684hash\u503c\n         string encodeText =util.encryptBySalt(newStr);\n        vec.push_back(encodeText);\n    }\n    for (size_t i = 0; i < 10; i++)\n    {\n        cout << \"md5\u52a0\u76d0\u540e\u52a0\u5bc6\u7684md5\u503cH\"+ to_string(i + 1) + \":\" + vec[i]<< endl;\n    }\n    for (size_t i = 0; i < 10; i++)\n    {\n        \/\/\u8ba1\u7b97H0\u548cH\u7684\u76f8\u4f3c\u5ea6\n        cout << \"H0\u548cH\" + to_string(i + 1) + \"\u7684\u76f8\u4f3c\u5ea6:\" + to_string(util.similarityDegree(md0, vec[i])) << endl;\n    }\n}<\/code><\/pre>\n\n\n\n
\"[\u5916\u94fe\u56fe\u7247\u8f6c\u5b58\u4e2d\u2026(img-GMQD1fac-1607789521383)]\"\/<\/figure >\n