C++呼叫openssl實現DES加密解密cbc模式 zeropadding填充方式 pkcs5padding填充方式 pkcs7padding填充方式
阿新 • • 發佈：2018-12-26
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des cbc 加密 zeropadding填充方式
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//加密 cbc zeropadding 自己實現 std::string des_cbc_zero_encrypt(const std::string &clearText, const std::string &key) { static unsigned char cbc_iv[8] = {'j', 'k', 't', '1', '2', '3', '4', '5'}; //初始化IV向量 std::string strCipherText; DES_cblock keyEncrypt, ivec; memset(keyEncrypt, 0, 8); if (key.length() <= 8) memcpy(keyEncrypt, key.c_str(), key.length()); else memcpy(keyEncrypt, key.c_str(), 8); DES_key_schedule keySchedule;//金鑰表 DES_set_key_unchecked(&keyEncrypt, &keySchedule); //設定金鑰，且不檢測金鑰奇偶性 memcpy(ivec, cbc_iv, sizeof(cbc_iv)); // 迴圈加密，每8位元組一次 const_DES_cblock inputText; DES_cblock outputText; std::vector<unsigned char> vecCiphertext; unsigned char tmp[8];for (int i = 0; i < clearText.length() / 8; i++) { memcpy(inputText, clearText.c_str() + i * 8, 8); DES_ncbc_encrypt(inputText, outputText, 8, &keySchedule, &ivec, DES_ENCRYPT); //加密 memcpy(tmp, outputText, 8); for (int j = 0; j < 8; j++) vecCiphertext.push_back(tmp[j]); //重置ivec memcpy(ivec, outputText, 8); } if (clearText.length() % 8 != 0) { int tmp1 = clearText.length() / 8 * 8; int tmp2 = clearText.length() - tmp1; memset(inputText, 0, 8); memcpy(inputText, clearText.c_str() + tmp1, tmp2); // 加密函式 DES_ncbc_encrypt(inputText, outputText, 8, &keySchedule, &ivec, DES_ENCRYPT); //加密 memcpy(tmp, outputText, 8); for (int j = 0; j < 8; j++) vecCiphertext.push_back(tmp[j]); } strCipherText.clear(); strCipherText.assign(vecCiphertext.begin(), vecCiphertext.end()); return strCipherText; }
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des cbc 加密 pkcs5padding填充方式 pkcs7padding跟pkcs5padding是一致的
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//加密 cbc pkcs5padding 自己實現 //pkcs7padding 跟 pkcs5padding是一樣的 std::string des_cbc_pkcs5_encrypt(const std::string &clearText, const std::string &key) { static unsigned char cbc_iv[8] = {'j', 'k', 't', '1', '2', '3', '4', '5'}; //初始化IV向量 std::string strCipherText; DES_cblock keyEncrypt, ivec; memset(keyEncrypt, 0, 8); if (key.length() <= 8) memcpy(keyEncrypt, key.c_str(), key.length()); else memcpy(keyEncrypt, key.c_str(), 8); DES_key_schedule keySchedule; //金鑰表 DES_set_key_unchecked(&keyEncrypt, &keySchedule); //設定金鑰，且不檢測金鑰奇偶性 memcpy(ivec, cbc_iv, sizeof(cbc_iv)); // 迴圈加密，每8位元組一次 const_DES_cblock inputText; DES_cblock outputText; std::vector<unsigned char> vecCiphertext; unsigned char tmp[8]; for (int i = 0; i < clearText.length() / 8; i++) { memcpy(inputText, clearText.c_str() + i * 8, 8); DES_ncbc_encrypt(inputText, outputText, 8, &keySchedule, &ivec, DES_ENCRYPT); //加密 memcpy(tmp, outputText, 8); for (int j = 0; j < 8; j++) vecCiphertext.push_back(tmp[j]); //重置ivec memcpy(ivec, outputText, 8); } if (clearText.length() % 8 != 0) { int tmp1 = clearText.length() / 8 * 8; int tmp2 = clearText.length() - tmp1; memset(inputText,(8-tmp2), 8); memcpy(inputText, clearText.c_str() + tmp1, tmp2); } else { memset(inputText,8, 8); } // 加密函式 DES_ncbc_encrypt(inputText, outputText, 8, &keySchedule, &ivec, DES_ENCRYPT); //加密 memcpy(tmp, outputText, 8); for (int j = 0; j < 8; j++) vecCiphertext.push_back(tmp[j]); strCipherText.clear(); strCipherText.assign(vecCiphertext.begin(), vecCiphertext.end()); return strCipherText; }
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des cbc 解密 zeropadding pkcs5padding pkcs7padding都是一致的
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//解密 cbc pkcs5padding 自己實現 //zeropadding / pkcs7padding 跟 pkcs5padding是一樣的 std::string des_cbc_pkcs5_decrypt(const std::string &cipherText, const std::string &key) { static unsigned char cbc_iv[8] = {'j', 'k', 't', '1', '2', '3', '4', '5'}; //初始化IV向量 std::string clearText; DES_cblock keyEncrypt, ivec; memset(keyEncrypt, 0, 8); if (key.length() <= 8) memcpy(keyEncrypt, key.c_str(), key.length()); else memcpy(keyEncrypt, key.c_str(), 8); DES_key_schedule keySchedule; //金鑰表 DES_set_key_unchecked(&keyEncrypt, &keySchedule); //設定金鑰，且不檢測金鑰奇偶性 memcpy(ivec, cbc_iv, sizeof(cbc_iv)); // 迴圈解密，每8位元組一次 const_DES_cblock inputText; DES_cblock outputText; std::vector<unsigned char> vecCleartext; unsigned char tmp[8]; for (int i = 0; i < cipherText.length() / 8; i++) { memcpy(inputText, cipherText.c_str() + i * 8, 8); DES_ncbc_encrypt(inputText, outputText, 8, &keySchedule, &ivec, DES_DECRYPT); //解密 memcpy(tmp, outputText, 8); for (int j = 0; j < 8; j++) vecCleartext.push_back(tmp[j]); //重置ivec //memcpy(ivec, outputText, 8); //解密過程不需要用前一塊的結果作為下一塊的IV } if (clearText.length() % 8 != 0) { int tmp1 = clearText.length() / 8 * 8; int tmp2 = clearText.length() - tmp1; memset(inputText,0, tmp2); memcpy(inputText, cipherText.c_str() + tmp1, tmp2); DES_ncbc_encrypt(inputText, outputText, tmp2, &keySchedule, &ivec, DES_DECRYPT); //解密 memcpy(tmp, outputText, tmp2); for (int j = 0; j < 8; j++) vecCleartext.push_back(tmp[j]); } clearText.clear(); clearText.assign(vecCleartext.begin(), vecCleartext.end()); return clearText; }
附I：DES加解密 cbc模式 的簡單講解 && C++用openssl庫來實現的注意事項