c++实现md5加密的代码 c++实现md5加密的代码

最近发现md5加密算法挺有趣，特点是单向加密不可逆，加密后的字符串长度相等，于是就用C++尝试实现了一下
头文件定义

/********************************************************* brief: md5 encryption* author: Monkey.Knight********************************************************/#ifndef __MD5_ENCODE_H__#define __MD5_ENCODE_H__// std#include // define#define UInt32 unsigned int#define BIT_OF_BYTE8#define BIT_OF_GROUP 512#define SRC_DATA_LEN 64// 四个非线性函数宏定义#define DEF_F(X, Y, Z ) ((( (X) & (Y) )|((~X)&(Z))))#define DEF_G(X, Y, Z)(((X)&(Z))|((Y)&(~Z)))#define DEF_H(X, Y, Z)((X)^(Y)^(Z))#define DEF_I(X, Y, Z)((Y)^((X)|(~Z)))// 求链接数函数宏定义#define FF(a, b, c, d, Mj, s, ti)(a = b + CycleMoveLeft((a + DEF_F(b,c,d) + Mj + ti),s)); #define GG(a, b, c, d, Mj, s, ti)(a = b + CycleMoveLeft((a + DEF_G(b,c,d) + Mj + ti),s)); #define HH(a, b, c, d, Mj, s, ti)(a = b + CycleMoveLeft((a + DEF_H(b,c,d) + Mj + ti),s)); #define II(a, b, c, d, Mj, s, ti)(a = b + CycleMoveLeft((a + DEF_I(b,c,d) + Mj + ti),s)); class Md5Encode {public:// 4轮循环算法struct ParamDynamic{UInt32 ua_; UInt32 ub_; UInt32 uc_; UInt32 ud_; UInt32 va_last_; UInt32 vb_last_; UInt32 vc_last_; UInt32 vd_last_; }; public:Md5Encode() {}std::string Encode(std::string src_info); protected:UInt32 CycleMoveLeft(UInt32 src_num, int bit_num_to_move); UInt32 FillData(const char *in_data_ptr, int data_byte_len, char** out_data_ptr); void RoundF(char *data_512_ptr, ParamDynamic & param); void RoundG(char *data_512_ptr, ParamDynamic & param); void RoundH(char *data_512_ptr, ParamDynamic & param); void RoundI(char *data_512_ptr, ParamDynamic & param); void RotationCalculate(char *data_512_ptr, ParamDynamic & param); std::string GetHexStr(unsigned int num_str); private:// 幻数定义static const int kA; static const int kB; static const int kC; static const int kD; static const unsigned long long k_ti_num_integer; }; #endif

源文件:

#include "md5_encode.h"#include // 幻数定义const int Md5Encode::kA = 0x67452301; const int Md5Encode::kB = 0xefcdab89; const int Md5Encode::kC = 0x98badcfe; const int Md5Encode::kD = 0x10325476; const unsigned long long Md5Encode::k_ti_num_integer = 4294967296; // function: CycleMoveLeft// @param src_num:要左移的数// @param bit_num_to_move:要移动的bit位数// @return循环左移后的结果数UInt32 Md5Encode::CycleMoveLeft(UInt32 src_num, int bit_num_to_move) {UInt32 src_num1 = src_num; UInt32 src_num2 = src_num; if (0 >= bit_num_to_move) {return src_num; }UInt32 num1 = src_num1 << bit_num_to_move; UInt32 num2 = src_num2 >> (32 - bit_num_to_move); return ((src_num1 << bit_num_to_move) \| (src_num2 >> (32 - bit_num_to_move))); }// function: FillData// @param in_data_ptr:要加密的信息数据// @param data_byte_len: 数据的字节数// @param out_data_ptr:填充必要信息后的数据// return : 填充信息后的数据长度,以字节为单位UInt32 Md5Encode::FillData(const char *in_data_ptr, int data_byte_len, char** out_data_ptr) {int bit_num = data_byte_len*BIT_OF_BYTE; int grop_num = bit_num / BIT_OF_GROUP; int mod_bit_num = bit_num % BIT_OF_GROUP; int bit_need_fill = 0; if (mod_bit_num > (BIT_OF_GROUP - SRC_DATA_LEN)) {bit_need_fill = (BIT_OF_GROUP - mod_bit_num); bit_need_fill += (BIT_OF_GROUP - SRC_DATA_LEN); }else {bit_need_fill = (BIT_OF_GROUP - SRC_DATA_LEN) - mod_bit_num; //这里多加了一个BIT_OF_GROUP，避免bit_need_fill正好等于0,暂时不加}int all_bit = bit_num + bit_need_fill; if (0 < bit_need_fill) {*out_data_ptr = new char[all_bit / BIT_OF_BYTE + SRC_DATA_LEN / BIT_OF_BYTE]; memset(*out_data_ptr, 0, all_bit / BIT_OF_BYTE + SRC_DATA_LEN / BIT_OF_BYTE); // copy datamemcpy(*out_data_ptr, in_data_ptr, data_byte_len); // fill rest dataunsigned char *tmp = reinterpret_cast(*out_data_ptr); tmp += data_byte_len; // fill 1 and 0*tmp = 0x80; // fill origin data lenunsigned long long * origin_num = (unsigned long long *)((*out_data_ptr) + ((all_bit / BIT_OF_BYTE))); *origin_num = data_byte_len*BIT_OF_BYTE; }return (all_bit / BIT_OF_BYTE + SRC_DATA_LEN / BIT_OF_BYTE); }void Md5Encode::RoundF(char *data_BIT_OF_GROUP_ptr, ParamDynamic & param) {UInt32 *M = reinterpret_cast(data_BIT_OF_GROUP_ptr); int s[] = { 7, 12, 17, 22 }; for (int i = 0; i < 16; ++i) {UInt32 ti = k_ti_num_integer * abs(sin(i + 1)); if (i % 4 == 0) {FF(param.ua_, param.ub_, param.uc_, param.ud_, M[i], s[i % 4], ti); }else if (i % 4 == 1) {FF(param.ud_, param.ua_, param.ub_, param.uc_, M[i], s[i % 4], ti); }else if (i % 4 == 2) {FF(param.uc_, param.ud_, param.ua_, param.ub_, M[i], s[i % 4], ti); }else if (i % 4 == 3) {FF(param.ub_, param.uc_, param.ud_, param.ua_, M[i], s[i % 4], ti); }}}void Md5Encode::RoundG(char *data_BIT_OF_GROUP_ptr, ParamDynamic & param) {UInt32 *M = reinterpret_cast(data_BIT_OF_GROUP_ptr); int s[] = { 5, 9, 14, 20 }; for (int i = 0; i < 16; ++i) {UInt32 ti = k_ti_num_integer * abs(sin(i + 1 + 16)); int index = (i * 5 + 1) % 16; if (i % 4 == 0) {GG(param.ua_, param.ub_, param.uc_, param.ud_, M[index], s[i % 4], ti); }else if (i % 4 == 1) {GG(param.ud_, param.ua_, param.ub_, param.uc_, M[index], s[i % 4], ti); }else if (i % 4 == 2) {GG(param.uc_, param.ud_, param.ua_, param.ub_, M[index], s[i % 4], ti); }else if (i % 4 == 3) {GG(param.ub_, param.uc_, param.ud_, param.ua_, M[index], s[i % 4], ti); }}}void Md5Encode::RoundH(char *data_BIT_OF_GROUP_ptr, ParamDynamic & param) {UInt32 *M = reinterpret_cast(data_BIT_OF_GROUP_ptr); int s[] = { 4, 11, 16, 23 }; for (int i = 0; i < 16; ++i) {UInt32 ti = k_ti_num_integer * abs(sin(i + 1 + 32)); int index = (i * 3 + 5) % 16; if (i % 4 == 0) {HH(param.ua_, param.ub_, param.uc_, param.ud_, M[index], s[i % 4], ti); }else if (i % 4 == 1) {HH(param.ud_, param.ua_, param.ub_, param.uc_, M[index], s[i % 4], ti); }else if (i % 4 == 2) {HH(param.uc_, param.ud_, param.ua_, param.ub_, M[index], s[i % 4], ti); }else if (i % 4 == 3) {HH(param.ub_, param.uc_, param.ud_, param.ua_, M[index], s[i % 4], ti); }}}void Md5Encode::RoundI(char *data_BIT_OF_GROUP_ptr, ParamDynamic & param) {UInt32 *M = reinterpret_cast(data_BIT_OF_GROUP_ptr); int s[] = { 6, 10, 15, 21 }; for (int i = 0; i < 16; ++i) {UInt32 ti = k_ti_num_integer * abs(sin(i + 1 + 48)); int index = (i * 7 + 0) % 16; if (i % 4 == 0) {II(param.ua_, param.ub_, param.uc_, param.ud_, M[index], s[i % 4], ti); }else if (i % 4 == 1) {II(param.ud_, param.ua_, param.ub_, param.uc_, M[index], s[i % 4], ti); }else if (i % 4 == 2) {II(param.uc_, param.ud_, param.ua_, param.ub_, M[index], s[i % 4], ti); }else if (i % 4 == 3) {II(param.ub_, param.uc_, param.ud_, param.ua_, M[index], s[i % 4], ti); }}}void Md5Encode::RotationCalculate(char *data_512_ptr, ParamDynamic & param) {if (NULL == data_512_ptr) {return; }RoundF(data_512_ptr, param); RoundG(data_512_ptr, param); RoundH(data_512_ptr, param); RoundI(data_512_ptr, param); param.ua_ = param.va_last_ + param.ua_; param.ub_ = param.vb_last_ + param.ub_; param.uc_ = param.vc_last_ + param.uc_; param.ud_ = param.vd_last_ + param.ud_; param.va_last_ = param.ua_; param.vb_last_ = param.ub_; param.vc_last_ = param.uc_; param.vd_last_ = param.ud_; }// 转换成十六进制字符串输出std::string Md5Encode::GetHexStr(unsigned int num_str) {std::string hexstr = ""; char szch[] = { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'a', 'b', 'c', 'd', 'e', 'f' }; unsigned char *tmptr = (unsigned char *)&num_str; int len = sizeof(num_str); // 小端字节序，逆序打印for (int i = 0; i < len; i++){unsigned char ch = tmptr[i] & 0xF0; ch = ch >> 4; hexstr.append(1, szch[ch]); ch = tmptr[i] & 0x0F; hexstr.append(1, szch[ch]); }return hexstr; }// function: Encode// @param src_info:要加密的信息// return :加密后的MD5值std::string Md5Encode::Encode(std::string src_info) {ParamDynamic param; param.ua_ = kA; param.ub_ = kB; param.uc_ = kC; param.ud_ = kD; param.va_last_ = kA; param.vb_last_ = kB; param.vc_last_ = kC; param.vd_last_ = kD; std::string result; const char *src_data = https://www.it610.com/article/src_info.c_str(); char *out_data_ptr = NULL; int total_byte = FillData(src_data, strlen(src_data), &out_data_ptr); //char * data_BIT_OF_GROUP = out_data_ptr; for (int i = 0; i < total_byte / (BIT_OF_GROUP / BIT_OF_BYTE); ++i) {char * data_BIT_OF_GROUP = out_data_ptr; data_BIT_OF_GROUP += i*(BIT_OF_GROUP / BIT_OF_BYTE); RotationCalculate(data_BIT_OF_GROUP, param); }if (NULL != out_data_ptr) {delete[] out_data_ptr, out_data_ptr = NULL; }result.append(GetHexStr(param.ua_)); result.append(GetHexStr(param.ub_)); result.append(GetHexStr(param.uc_)); result.append(GetHexStr(param.ud_)); return result; }

测试：

#include #include #include "md5_encode.h"int main(int argc, char* argv[]) {std::string src = "https://www.it610.com/article/fasdfasdfasdfnmmw,enrsudfnsmndfejkjhuasdmnf"; Md5Encode encode_obj; std::string ret = encode_obj.Encode(src); std::cout << "info: " << src.c_str() << std::endl; std::cout << "md5: " << ret.c_str() << std::endl; return 0; }

结果：