文章目錄

• 一、文件加密解密操作
• • 1、解密整 4096 字節的數據
  • 2、解密小于 4096 字節的數據
• 二、完整代碼示例
• • 1、文件加密操作 main.c
  • 2、DES 加密解密頭文件 des.h
  • 3、第三方 DES 加密解密函數庫源碼 des.c

一、文件加密解密操作

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準備 $2$ 個文件 , 一個是原始文件 , 一個是加密后的文件 , 將原始文件進行加密 , 然后將加密后的數據輸出到加密文件中 ;

// 要解密的文件const char *input_file= "D:/File/config_encode.ini";// 解密后的文件const char *output_file = "D:/File/config_decode.ini";// 將 要加密的 input_file 文件加密 , 并輸出到 output_file 文件中ret = file_decode(input_file, output_file);

1、解密整 4096 字節的數據

打開輸入文件 , 每次從輸入文件中 , 讀取 $4096$ 字節數據 , 將這 $4096$ 字節數據解密 , 然后寫出到解密文件中 ;

// 循環讀取輸入文件中的數據while (!feof(fp_in)){// 嘗試從輸入文件中讀取 4K 數據input_len = fread(input_buffer, 1, 4096, fp_in);// 如果讀取完畢 , 直接退出if (feof(fp_in)){break;}// 解密 4096 字節數據ret = des_decode_raw(input_buffer, input_len, output_buffer, &output_len);// 如果加密失敗, 直接退出if (ret != 0){printf("error : des_encode_raw \n", ret);goto END;}// 將解密后的數據 , 寫出到輸出文件中output_tmplen = fwrite(output_buffer, 1, output_len, fp_out);// 如果寫出失敗 , 直接退出if (output_tmplen != output_len){ret = -3;printf("error : fwrite\n");goto END;}}

2、解密小于 4096 字節的數據

如果讀取的數據小于 $4096$ 字節 , 會退出循環 , 執行下面的業務邏輯 ;

下面的函數主要是 解密小于 4096 字節數據 , 加密完成后 , 將解密數據輸出到文件中 ;

// 解密小于 4096 字節數據ret = des_decode(input_buffer, input_len, output_buffer, &output_len);// 加密失敗 , 直接退出if (ret != 0){printf("error : des_decode \n", ret);goto END;}// 將解密后的數據 , 寫出到輸出文件中output_tmplen = fwrite(output_buffer, 1, output_len, fp_out);// 如果寫出失敗 , 直接退出if (output_len != output_tmplen){ret = -3;printf("error : fwrite\n");goto END;}

二、完整代碼示例

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1、文件加密操作 main.c

#define _CRT_SECURE_NO_WARNINGS #include <stdlib.h> #include <string.h> #include <stdio.h> #include "des.h"/*** @brief file_encode 文件加密* @param input_file 被加密的文件* @param output_file 加密后的文件* @return*/ int file_encode(const char *input_file, const char *output_file) {// 用于接收各個步驟的返回值 , 做校驗int ret = 0;// 輸入 文件 指針FILE *fp_in= NULL;// 輸出 文件 指針FILE *fp_out = NULL;// 輸入緩沖區 , 大小 4Kunsigned char input_buffer[4096] = {0};// 輸入數據字節數int input_len = 0;// 輸出文件緩沖區unsigned char output_buffer[4096] = {0};// 輸出數據字節數int output_len = 0;// 輸出數據寫出字節數 , 用于與上面的 output_len 進行對比// 一般情況下這兩個值相等 , 如果出錯 , 直接退出程序int output_tmplen;// 打開輸入文件fp_in = fopen(input_file, "rb");if (fp_in == NULL){goto END;}// 打開輸出文件fp_out = fopen(output_file, "wb");if (fp_out == NULL){goto END;}// 循環讀取輸入文件中的數據while (!feof(fp_in)){// 嘗試從輸入文件中讀取 4K 數據input_len = fread(input_buffer, 1, 4096, fp_in);// 如果讀取完畢 , 直接退出if (feof(fp_in)){break;}// 加密 4096 字節數據ret = des_encode_raw(input_buffer, input_len, output_buffer, &output_len);// 如果加密失敗, 直接退出if (ret != 0){printf("error : des_encode_raw \n", ret);goto END;}// 將加密后的數據 , 寫出到輸出文件中output_tmplen = fwrite(output_buffer, 1, output_len, fp_out);// 如果寫出失敗 , 直接退出if (output_tmplen != output_len){ret = -3;printf("error : fwrite\n");goto END;}}// 加密小于 4096 字節數據ret = des_encode(input_buffer, input_len, output_buffer, &output_len);// 加密失敗 , 直接退出if (ret != 0){printf("error : des_encode \n", ret);goto END;}// 將加密后的數據 , 寫出到輸出文件中output_tmplen = fwrite(output_buffer, 1, output_len, fp_out);// 如果寫出失敗 , 直接退出if (output_len != output_tmplen){ret = -3;printf("error : fwrite\n");goto END;}END:// 關閉輸入文件if (fp_in != NULL){fclose(fp_in);}// 關閉輸出文件if (fp_out != NULL){fclose(fp_out);}return 0; }int main_encode() {// 接收 子函數 返回值int ret = 0;// 要加密的文件const char *input_file= "D:/File/config.ini";// 加密后的文件const char *output_file = "D:/File/config_encode.ini";// 將 要加密的 input_file 文件加密 , 并輸出到 output_file 文件中ret = file_encode(input_file, output_file);// 加密失敗if (ret != 0){printf("error : file_encoder\n " );return ret;}system("pause");return ret; }/*** @brief file_decode 文件解密* @param input_file 被加密的文件* @param output_file 加密后的文件* @return*/ int file_decode(const char *input_file, const char *output_file) {// 用于接收各個步驟的返回值 , 做校驗int ret = 0;// 輸入 文件 指針FILE *fp_in= NULL;// 輸出 文件 指針FILE *fp_out = NULL;// 輸入緩沖區 , 大小 4Kunsigned char input_buffer[4096] = {0};// 輸入數據字節數int input_len = 0;// 輸出文件緩沖區unsigned char output_buffer[4096] = {0};// 輸出數據字節數int output_len = 0;// 輸出數據寫出字節數 , 用于與上面的 output_len 進行對比// 一般情況下這兩個值相等 , 如果出錯 , 直接退出程序int output_tmplen;// 打開輸入文件fp_in = fopen(input_file, "rb");if (fp_in == NULL){goto END;}// 打開輸出文件fp_out = fopen(output_file, "wb");if (fp_out == NULL){goto END;}// 循環讀取輸入文件中的數據while (!feof(fp_in)){// 嘗試從輸入文件中讀取 4K 數據input_len = fread(input_buffer, 1, 4096, fp_in);// 如果讀取完畢 , 直接退出if (feof(fp_in)){break;}// 解密 4096 字節數據ret = des_decode_raw(input_buffer, input_len, output_buffer, &output_len);// 如果加密失敗, 直接退出if (ret != 0){printf("error : des_encode_raw \n", ret);goto END;}// 將解密后的數據 , 寫出到輸出文件中output_tmplen = fwrite(output_buffer, 1, output_len, fp_out);// 如果寫出失敗 , 直接退出if (output_tmplen != output_len){ret = -3;printf("error : fwrite\n");goto END;}}// 解密小于 4096 字節數據ret = des_decode(input_buffer, input_len, output_buffer, &output_len);// 加密失敗 , 直接退出if (ret != 0){printf("error : des_decode \n", ret);goto END;}// 將解密后的數據 , 寫出到輸出文件中output_tmplen = fwrite(output_buffer, 1, output_len, fp_out);// 如果寫出失敗 , 直接退出if (output_len != output_tmplen){ret = -3;printf("error : fwrite\n");goto END;}END:// 關閉輸入文件if (fp_in != NULL){fclose(fp_in);}// 關閉輸出文件if (fp_out != NULL){fclose(fp_out);}return 0; }int main_decode() {// 接收 子函數 返回值int ret = 0;// 要解密的文件const char *input_file= "D:/File/config_encode.ini";// 解密后的文件const char *output_file = "D:/File/config_decode.ini";// 將 要加密的 input_file 文件加密 , 并輸出到 output_file 文件中ret = file_decode(input_file, output_file);// 加密失敗if (ret != 0){printf("error : file_encoder\n " );return ret;}system("pause");return ret; }int main() {// 文件加密//main_encode();// 文件解密main_decode();system("pause");return 0; }

2、DES 加密解密頭文件 des.h

/********************************************************** des.h* DES 加密算法頭文件*********************************************************/ #ifndef _DES_H_ #define _DES_H_#ifdef __cplusplus extern "C" { #endif/*** @brief des_encode_raw DES 加密操作 , 加密 4096 字節數據* @param in_data 輸入數據* @param in_data_len 輸入數據長度* @param out_data 輸出數據* @param out_data_len 輸出數據長度* @return*/ int des_encode_raw(unsigned char *in_data,int in_data_len,unsigned char *out_data,int *out_data_len);/*** @brief des_encode DES 加密操作 , 加密少于 4096 字節數據* @param in_data 輸入數據* @param in_data_len 輸入數據長度* @param out_data 輸出數據* @param out_data_len 輸出數據長度* @return*/ int des_encode(unsigned char *in_data,int in_data_len,unsigned char *out_data,int *out_data_len);/*** @brief des_decode_raw DES 解密操作 , 解密 4096 字節* @param in_data 輸入數據* @param in_data_len 輸入數據長度* @param out_data 輸出數據* @param out_data_len 輸出數據長度* @return*/ int des_decode_raw(unsigned char *in_data,int in_data_len,unsigned char *out_data,int *out_data_len);/*** @brief des_decode DES 解密操作 , 解密少于 4096 字節* @param in_data 輸入數據* @param in_data_len 輸入數據長度* @param out_data 輸出數據* @param out_data_len 輸出數據長度* @return*/ int des_decode(unsigned char *in_data,int in_data_len,unsigned char *out_data,int *out_data_len);#ifdef __cplusplus } #endif#endif

3、第三方 DES 加密解密函數庫源碼 des.c

/******************************************************** des.c* common des......*******************************************************/#include <stdlib.h> #include <string.h> #include <stdio.h> #include "des.h"/*********************************************************data type definition for Des; **********************************************************/ #define EN0 0 #define DE1 1#define DES_KEYBYTES 128 #define DES_KEYLONGS 32 #define DES_BLOCKLEN 8typedef struct {unsigned char ek[DES_KEYBYTES];int ekLen;unsigned char dk[DES_KEYBYTES];int dkLen;unsigned char CbcCtx[DES_BLOCKLEN]; } DES_CTX;typedef struct {unsigned char ek1[DES_KEYBYTES];int ek1Len;unsigned char dk1[DES_KEYBYTES];int dk1Len;unsigned char ek2[DES_KEYBYTES];int ek2Len;unsigned char dk2[DES_KEYBYTES];int dk2Len;unsigned char CbcCtx[DES_BLOCKLEN];//int IsFirstBlock; } DES3_CTX;static unsigned char pc1[56] = {56, 48, 40, 32, 24, 16, 8, 0, 57, 49, 41, 33, 25, 17,9, 1, 58, 50, 42, 34, 26, 18, 10, 2, 59, 51, 43, 35,62, 54, 46, 38, 30, 22, 14, 6, 61, 53, 45, 37, 29, 21,13, 5, 60, 52, 44, 36, 28, 20, 12, 4, 27, 19, 11, 3 };static unsigned char pc2[48] = {13, 16, 10, 23, 0, 4, 2, 27, 14, 5, 20, 9,22, 18, 11, 3, 25, 7, 15, 6, 26, 19, 12, 1,40, 51, 30, 36, 46, 54, 29, 39, 50, 44, 32, 47,43, 48, 38, 55, 33, 52, 45, 41, 49, 35, 28, 31 };static unsigned short bytebit[8] = {0200,0100,040,020,010,04,02,01 }; static unsigned char totrot[16] = {1,2,4,6,8,10,12,14,15,17,19,21,23,25,27,28}; static unsigned long bigbyte[24] = {0x800000L, 0x400000L, 0x200000L, 0x100000L,0x80000L, 0x40000L, 0x20000L, 0x10000L,0x8000L, 0x4000L, 0x2000L, 0x1000L,0x800L, 0x400L, 0x200L, 0x100L,0x80L, 0x40L, 0x20L, 0x10L,0x8L, 0x4L, 0x2L, 0x1L };//insert digits static unsigned long SP1[64] ={0x01010400l,0x00000000l,0x00010000l,0x01010404l,0x01010004l,0x00010404l,0x00000004l,0x00010000l,0x00000400l,0x01010400l,0x01010404l,0x00000400l,0x01000404l,0x01010004l,0x01000000l,0x00000004l,0x00000404l,0x01000400l,0x01000400l,0x00010400l,0x00010400l,0x01010000l,0x01010000l,0x01000404l,0x00010004l,0x01000004l,0x01000004l,0x00010004l,0x00000000l,0x00000404l,0x00010404l,0x01000000l,0x00010000l,0x01010404l,0x00000004l,0x01010000l,0x01010400l,0x01000000l,0x01000000l,0x00000400l,0x01010004l,0x00010000l,0x00010400l,0x01000004l,0x00000400l,0x00000004l,0x01000404l,0x00010404l,0x01010404l,0x00010004l,0x01010000l,0x01000404l,0x01000004l,0x00000404l,0x00010404l,0x01010400l,0x00000404l,0x01000400l,0x01000400l,0x00000000l,0x00010004l,0x00010400l,0x00000000l,0x01010004l };static unsigned long SP2[64]={0x80108020l,0x80008000l,0x00008000l,0x00108020l,0x00100000l,0x00000020l,0x80100020l,0x80008020l,0x80000020l,0x80108020l,0x80108000l,0x80000000l,0x80008000l,0x00100000l,0x00000020l,0x80100020l,0x00108000l,0x00100020l,0x80008020l,0x00000000l,0x80000000l,0x00008000l,0x00108020l,0x80100000l,0x00100020l,0x80000020l,0x00000000l,0x00108000l,0x00008020l,0x80108000l,0x80100000l,0x00008020l,0x00000000l,0x00108020l,0x80100020l,0x00100000l,0x80008020l,0x80100000l,0x80108000l,0x00008000l,0x80100000l,0x80008000l,0x00000020l,0x80108020l,0x00108020l,0x00000020l,0x00008000l,0x80000000l,0x00008020l,0x80108000l,0x00100000l,0x80000020l,0x00100020l,0x80008020l,0x80000020l,0x00100020l,0x00108000l,0x00000000l,0x80008000l,0x00008020l,0x80000000l,0x80100020l,0x80108020l,0x00108000l };static unsigned long SP3[64]={ 0x00000208l,0x08020200l,0x00000000l,0x08020008l,0x08000200l,0x00000000l,0x00020208l,0x08000200l,0x00020008l,0x08000008l,0x08000008l,0x00020000l,0x08020208l,0x00020008l,0x08020000l,0x00000208l,0x08000000l,0x00000008l,0x08020200l,0x00000200l,0x00020200l,0x08020000l,0x08020008l,0x00020208l,0x08000208l,0x00020200l,0x00020000l,0x08000208l,0x00000008l,0x08020208l,0x00000200l,0x08000000l,0x08020200l,0x08000000l,0x00020008l,0x00000208l,0x00020000l,0x08020200l,0x08000200l,0x00000000l,0x00000200l,0x00020008l,0x08020208l,0x08000200l,0x08000008l,0x00000200l,0x00000000l,0x08020008l,0x08000208l,0x00020000l,0x08000000l,0x08020208l,0x00000008l,0x00020208l,0x00020200l,0x08000008l,0x08020000l,0x08000208l,0x00000208l,0x08020000l,0x00020208l,0x00000008l,0x08020008l,0x00020200l };static unsigned long SP4[64]={ 0x00802001l,0x00002081l,0x00002081l,0x00000080l,0x00802080l,0x00800081l,0x00800001l,0x00002001l,0x00000000l,0x00802000l,0x00802000l,0x00802081l,0x00000081l,0x00000000l,0x00800080l,0x00800001l,0x00000001l,0x00002000l,0x00800000l,0x00802001l,0x00000080l,0x00800000l,0x00002001l,0x00002080l,0x00800081l,0x00000001l,0x00002080l,0x00800080l,0x00002000l,0x00802080l,0x00802081l,0x00000081l,0x00800080l,0x00800001l,0x00802000l,0x00802081l,0x00000081l,0x00000000l,0x00000000l,0x00802000l,0x00002080l,0x00800080l,0x00800081l,0x00000001l,0x00802001l,0x00002081l,0x00002081l,0x00000080l,0x00802081l,0x00000081l,0x00000001l,0x00002000l,0x00800001l,0x00002001l,0x00802080l,0x00800081l,0x00002001l,0x00002080l,0x00800000l,0x00802001l,0x00000080l,0x00800000l,0x00002000l,0x00802080l };static unsigned long SP5[64]={ 0x00000100l,0x02080100l,0x02080000l,0x42000100l,0x00080000l,0x00000100l,0x40000000l,0x02080000l,0x40080100l,0x00080000l,0x02000100l,0x40080100l,0x42000100l,0x42080000l,0x00080100l,0x40000000l,0x02000000l,0x40080000l,0x40080000l,0x00000000l,0x40000100l,0x42080100l,0x42080100l,0x02000100l,0x42080000l,0x40000100l,0x00000000l,0x42000000l,0x02080100l,0x02000000l,0x42000000l,0x00080100l,0x00080000l,0x42000100l,0x00000100l,0x02000000l,0x40000000l,0x02080000l,0x42000100l,0x40080100l,0x02000100l,0x40000000l,0x42080000l,0x02080100l,0x40080100l,0x00000100l,0x20000000l,0x42080000l,0x42080100l,0x00080100l,0x42000000l,0x42080100l,0x02080000l,0x02000100l,0x40000100l,0x00080000l,0x00080100l,0x02000100l,0x40000100l,0x00080000l,0x00000000l,0x40080000l,0x02080100l,0x40000100l };static unsigned long SP6[64]={ 0x20000010l,0x20400000l,0x00004000l,0x20404010l,0x20400000l,0x00000010l,0x20404010l,0x00400000l,0x20004000l,0x00404010l,0x00400000l,0x20000010l,0x00400010l,0x20004000l,0x20000000l,0x00004010l,0x00000000l,0x00400010l,0x20004010l,0x00004000l,0x00404000l,0x20004010l,0x00000010l,0x20400010l,0x20400010l,0x00000000l,0x00404010l,0x20404000l,0x00004010l,0x00404000l,0x20404000l,0x20000000l,0x20004000l,0x00000010l,0x20400010l,0x00404000l,0x20404010l,0x00400000l,0x00004010l,0x20000010l,0x00400000l,0x20004000l,0x20000000l,0x00004010l,0x20000010l,0x20404010l,0x00404000l,0x20400000l,0x00404010l,0x20404000l,0x00000000l,0x20400010l,0x00000010l,0x00004000l,0x20400000l,0x00404010l,0x00004000l,0x00400010l,0x20004010l,0x00000000l,0x20404000l,0x20000000l,0x00400010l,0x20004010l }; static unsigned long SP7[64] = {0x00200000L, 0x04200002L, 0x04000802L, 0x00000000L,0x00000800L, 0x04000802L, 0x00200802L, 0x04200800L,0x04200802L, 0x00200000L, 0x00000000L, 0x04000002L,0x00000002L, 0x04000000L, 0x04200002L, 0x00000802L,0x04000800L, 0x00200802L, 0x00200002L, 0x04000800L,0x04000002L, 0x04200000L, 0x04200800L, 0x00200002L,0x04200000L, 0x00000800L, 0x00000802L, 0x04200802L,0x00200800L, 0x00000002L, 0x04000000L, 0x00200800L,0x04000000L, 0x00200800L, 0x00200000L, 0x04000802L,0x04000802L, 0x04200002L, 0x04200002L, 0x00000002L,0x00200002L, 0x04000000L, 0x04000800L, 0x00200000L,0x04200800L, 0x00000802L, 0x00200802L, 0x04200800L,0x00000802L, 0x04000002L, 0x04200802L, 0x04200000L,0x00200800L, 0x00000000L, 0x00000002L, 0x04200802L,0x00000000L, 0x00200802L, 0x04200000L, 0x00000800L,0x04000002L, 0x04000800L, 0x00000800L, 0x00200002L };static unsigned long SP8[64] = {0x10001040L, 0x00001000L, 0x00040000L, 0x10041040L,0x10000000L, 0x10001040L, 0x00000040L, 0x10000000L,0x00040040L, 0x10040000L, 0x10041040L, 0x00041000L,0x10041000L, 0x00041040L, 0x00001000L, 0x00000040L,0x10040000L, 0x10000040L, 0x10001000L, 0x00001040L,0x00041000L, 0x00040040L, 0x10040040L, 0x10041000L,0x00001040L, 0x00000000L, 0x00000000L, 0x10040040L,0x10000040L, 0x10001000L, 0x00041040L, 0x00040000L,0x00041040L, 0x00040000L, 0x10041000L, 0x00001000L,0x00000040L, 0x10040040L, 0x00001000L, 0x00041040L,0x10001000L, 0x00000040L, 0x10000040L, 0x10040000L,0x10040040L, 0x10000000L, 0x00040000L, 0x10001040L,0x00000000L, 0x10041040L, 0x00040040L, 0x10000040L,0x10040000L, 0x10001000L, 0x10001040L, 0x00000000L,0x10041040L, 0x00041000L, 0x00041000L, 0x00001040L,0x00001040L, 0x00040040L, 0x10000000L, 0x10041000L };void deskey(unsigned char *key,short edf, unsigned long *kn); void cookey(register unsigned long *raw1, unsigned long *dough); //void cpkey(register unsigned long *into); //void usekey(register unsigned long *from); //void des(unsigned char *inblock,unsigned char *outblock); void scrunch(register unsigned char *outof, register unsigned long *into); void unscrun(register unsigned long *outof, register unsigned char *into); void desfunc(register unsigned long *block,register unsigned long *keys);/***************** DES Function *****************/ unsigned long OPENCOMM_DesExpandEncKey(unsigned char *pbDesKey,unsigned long ulDesKeyLen,unsigned char *pbDesEncKey,unsigned long *ulDesEncKeyLen);unsigned long OPENCOMM_DesExpandDecKey(unsigned char *pbDesKey,unsigned long ulDesKeyLen,unsigned char *pbDesDecKey,unsigned long *ulDesDecKeyLen);unsigned long OPENCOMM_DesEncRaw(unsigned char *pbDesEncKey,unsigned long ulDesEncKeyLen,unsigned char *pbInData,unsigned long ulInDataLen,unsigned char *pbOutData,unsigned long *ulOutDataLen);unsigned long OPENCOMM_DesDecRaw(unsigned char *pbDesDecKey,unsigned long ulDesDecKeyLen,unsigned char *pbInData,unsigned long ulInDataLen,unsigned char *pbOutData,unsigned long *ulOutDataLen);int myic_DESDecrypt(unsigned char *pDesKey,int nDesKeyLen,unsigned char *pInData,int nInDataLen,unsigned char *pOutData,int *pOutDataLen);int myic_DESEncrypt(unsigned char *pDesKey,int nDesKeyLen,unsigned char *pInData,int nInDataLen,unsigned char *pOutData,int *pOutDataLen);void deskey(unsigned char *key,short edf, unsigned long *kn) {register int i, j, l, m, n;unsigned long pc1m[56],pcr[56];for ( j = 0; j < 56; j++ ) {l = pc1[j];m = l & 07;pc1m[j] = (((unsigned long) key[l >> 3] & (unsigned long)bytebit[m] ) ? 1:0);}for ( i = 0;i < 16; i++){if ( edf == DE1 ) m = (15 - i) << 1;else m = i << 1;n = m + 1;kn[m] = kn[n] = 0L;for ( j = 0; j < 28; j++ ){l = j + totrot[i];if ( l < 28 ) pcr[j] = pc1m[l];else pcr[j] = pc1m[l-28];}for (j = 28; j < 56; j++ ) {l = j + totrot[i];if ( l < 56 ) pcr[j] = pc1m[l];else pcr[j] = pc1m[l-28];} for ( j = 0; j < 24; j++ ) {if ( pcr[pc2[j]] ) kn[m] |= bigbyte[j];if ( pcr[pc2[j+24]] ) kn[n] |= bigbyte[j];}}return; }void cookey(register unsigned long *raw1, unsigned long *dough) {register unsigned long *cook,*raw0;register int i;cook = dough;for ( i = 0; i < 16; i++, raw1++ ) {raw0 = raw1++;*cook = (*raw0 & 0x00fc0000L) << 6;*cook |= (*raw0 & 0x00000fc0L) << 10;*cook |= (*raw1 & 0x00fc0000L) >> 10;*cook++ |= (*raw1 & 0x00000fc0L) >> 6;*cook = (*raw0 & 0x0003f000L) << 12;*cook |= (*raw0 & 0x0000003fL) << 16;*cook |= (*raw1 & 0x0003f000L) >> 4;*cook++ |= (*raw1 & 0x0000003fL);}return; }void scrunch(register unsigned char *outof, register unsigned long *into) {*into = (*outof++ & 0xffL) << 24;*into |= (*outof++ & 0xffL) << 16;*into |= (*outof++ & 0xffL) << 8;*into++ |= (*outof++ & 0xffL);*into = (*outof++ & 0xffL) << 24;*into |= (*outof++ & 0xffL) << 16;*into |= (*outof++ & 0xffL) << 8;*into++ |= (*outof & 0xffL);return; }void unscrun(register unsigned long *outof, register unsigned char *into) {*into++ = (unsigned char)((*outof >> 24) & 0xffL);*into++ = (unsigned char)((*outof >> 16) & 0xffL);*into++ = (unsigned char)((*outof >> 8) & 0xffL);*into++ = (unsigned char)( *outof++ & 0xffL);*into++ = (unsigned char)((*outof >> 24) & 0xffL);*into++ = (unsigned char)((*outof >> 16) & 0xffL);*into++ = (unsigned char)((*outof >> 8) & 0xffL);*into = (unsigned char)( *outof & 0xffL);return; }void desfunc(register unsigned long *block,register unsigned long *keys) {register unsigned long fval, work, right, leftt;register int round;leftt = block[0];right = block[1];work = ((leftt >> 4) ^ right) & 0x0f0f0f0fL;right ^= work;leftt ^= (work << 4);work = ((leftt >> 16) ^ right) & 0x0000ffffL;right ^= work;leftt ^= (work << 16);work = ((right >> 2) ^ leftt) & 0x33333333L;leftt ^= work;right ^= (work << 2);work = ((right >> 8) ^ leftt) & 0x00ff00ffL;leftt ^= work;right ^= (work << 8);right = ((right << 1) | ((right >>31) & 1L)) & 0xffffffffL;work = (leftt ^ right) & 0xaaaaaaaaL;leftt ^= work;right ^= work;leftt = ((leftt << 1) | ((leftt >> 31)&1L)) & 0xffffffffL;for (round = 0; round < 8; round++) {work = (right << 28) | (right >> 4);work ^= *keys++;fval = SP7[ work & 0x3fL];fval |= SP5[(work >> 8) & 0x3fL];fval |= SP3[(work >> 16) & 0x3fL];fval |= SP1[(work >> 24) & 0x3fL];work = right ^ *keys++;fval |= SP8[ work & 0x3fL];fval |= SP6[(work >> 8) & 0x3fL];fval |= SP4[(work >> 16) & 0x3fL];fval |= SP2[(work >> 24) & 0x3fL];leftt ^= fval;work = (leftt << 28) | (leftt >> 4);work ^= *keys++;fval = SP7[ work & 0x3fL];fval |= SP5[(work >> 8) & 0x3fL];fval |= SP3[(work >> 16) & 0x3fL];fval |= SP1[(work >> 24) & 0x3fL];work = leftt ^ *keys++;fval |= SP8[ work & 0x3fL];fval |= SP6[(work >> 8) & 0x3fL];fval |= SP4[(work >> 16) & 0x3fL];fval |= SP2[(work >> 24) & 0x3fL];right ^= fval;}right = (right << 31) | (right >> 1);work = (leftt ^ right) & 0xaaaaaaaaL;leftt ^= work;right ^= work;leftt = (leftt << 31) | (leftt >> 1);work = ((leftt >> 8) ^ right) & 0x00ff00ffL;right ^= work;leftt ^= (work << 8);work = ((leftt >> 2) ^ right) & 0x33333333L;right ^= work;leftt ^= (work << 2);work = ((right >> 16) ^ leftt) & 0x0000ffffL;leftt ^= work;right ^= (work << 16);work = ((right >> 4) ^ leftt) & 0x0f0f0f0fL;leftt ^= work;right ^= (work << 4);*block++ = right;*block = leftt;return; }/*****************************************************************OPENCOMM_DesExpandEncKey : Expand Des Enc Key 擴展des加密密鑰Return value:0 : Successother : failedParameters:pbDesKey : 擴展前的DES密鑰(8字節) inputulDesKeyLen : 擴展前的DES密鑰長度 inputpbDesEncKey : 擴展后的DES加密密鑰(128字節) output*ulDesEncKeyLen : 擴展后的DES加密密鑰長度 output *****************************************************************/ unsigned long OPENCOMM_DesExpandEncKey(unsigned char *pbDesKey,unsigned long ulDesKeyLen,unsigned char *pbDesEncKey,unsigned long *ulDesEncKeyLen) {unsigned long kn[32], dough[32];if (ulDesKeyLen != 8)return 0xEE20;deskey(pbDesKey, EN0, kn);cookey(kn, dough);*ulDesEncKeyLen = DES_KEYBYTES; //32 long = 128 bytesmemcpy(pbDesEncKey, dough, *ulDesEncKeyLen);return 0; }/*****************************************************************OPENCOMM_DesExpandDecKey : Expand Des Dec Key 擴展des解密密鑰Return value:0 : Successother : failedParameters:pbDesKey : 擴展前的DES密鑰(8字節) inputulDesKeyLen : 擴展前的DES密鑰長度 inputpbDesDecKey : 擴展后的DES解密密鑰(128字節) output*ulDesDecKeyLen : 擴展后的DES解密密鑰長度 output *****************************************************************/ unsigned long OPENCOMM_DesExpandDecKey(unsigned char *pbDesKey,unsigned long ulDesKeyLen,unsigned char *pbDesDecKey,unsigned long *ulDesDecKeyLen) {unsigned long kn[32], dough[32];if (ulDesKeyLen != 8)return 0xEE20;deskey(pbDesKey, DE1, kn);cookey(kn, dough);*ulDesDecKeyLen = DES_KEYBYTES; //32 long = 128 bytesmemcpy(pbDesDecKey, dough, *ulDesDecKeyLen);return 0; }/****************************************************************OPENCOMM_DesEncRaw : Des算法加密小整塊明文8字節 Return value:0 : Successother : failedParameters:pbDesEncKey : DES加密密鑰 inputulDesEncKeyLen : DES加密密鑰長度 inputpbInData : 待加密的明文 inputulInDataLen : 待加密的明文長度 inputpbOutData : 加密后的密文 output*ulOutDataLen : 加密后的密文長度 output *****************************************************************/ unsigned long OPENCOMM_DesEncRaw(unsigned char *pbDesEncKey,unsigned long ulDesEncKeyLen,unsigned char *pbInData,unsigned long ulInDataLen,unsigned char *pbOutData,unsigned long *ulOutDataLen) {unsigned long work[2], ek[DES_KEYLONGS];unsigned char cp[DES_BLOCKLEN];if (ulInDataLen != DES_BLOCKLEN)return 0xEE20;if (ulDesEncKeyLen != DES_KEYBYTES)return 0xEE20;memcpy(cp, pbInData, DES_BLOCKLEN);scrunch(cp,work); // 8 bytes -> 2 longmemcpy(ek, pbDesEncKey, ulDesEncKeyLen);desfunc(work,ek);unscrun(work,cp); // 2 long -> 8 bytesmemcpy(pbOutData, cp, DES_BLOCKLEN);*ulOutDataLen = DES_BLOCKLEN;return 0; }/*****************************************************************OPENCOMM_DesDecRaw : Des算法解密小整塊密文8字節 Return value:0 : Successother : failedParameters:pbDesDecKey : DES解密密鑰 inputulDesDecKeyLen : DES解密密鑰長度 inputpbInData : 待解密的密文 inputulInDataLen : 待解密的密文長度 inputpbOutData : 解密后的明文 output*ulOutDataLen : 解密后的明文長度 output *****************************************************************/ unsigned long OPENCOMM_DesDecRaw(unsigned char *pbDesDecKey,unsigned long ulDesDecKeyLen,unsigned char *pbInData,unsigned long ulInDataLen,unsigned char *pbOutData,unsigned long *ulOutDataLen) {unsigned long work[2], dk[DES_KEYLONGS];unsigned char cp[DES_BLOCKLEN];if (ulInDataLen != DES_BLOCKLEN)return 0xEE20;if (ulDesDecKeyLen != DES_KEYBYTES)return 0xEE20;memcpy(cp, pbInData, DES_BLOCKLEN);scrunch(cp,work); // 8 bytes -> 2 longmemcpy(dk, pbDesDecKey, ulDesDecKeyLen);desfunc(work,dk);unscrun(work,cp); // 2 long -> 8 bytesmemcpy(pbOutData, cp, DES_BLOCKLEN); // des_enc(pbDesEncKey, pbInData, pbOutData);*ulOutDataLen = DES_BLOCKLEN;return 0; }/********************* DES *********************/int myic_DESEncrypt(unsigned char *pDesKey,int nDesKeyLen,unsigned char *pInData,int nInDataLen,unsigned char *pOutData,int *pOutDataLen) {unsigned char DesKeyBuf[32];unsigned char DesEncKeyBuf[128];int EncKeyLen, KeyLen = 0;int retval = 0, loops, i;if(nInDataLen%8 != 0)return 0xEE20;if(nDesKeyLen != 8)return 0xEE20;KeyLen = nDesKeyLen;memcpy(DesKeyBuf, pDesKey, nDesKeyLen);retval = OPENCOMM_DesExpandEncKey(DesKeyBuf, KeyLen,DesEncKeyBuf, (unsigned long *)&EncKeyLen);if(retval != 0)return retval;loops = nInDataLen/8;for(i = 0; i < loops; i++){retval = OPENCOMM_DesEncRaw(DesEncKeyBuf, EncKeyLen, pInData + i*8,8, pOutData + i*8, (unsigned long *)pOutDataLen);if(retval != 0)return retval;}*pOutDataLen = nInDataLen;return retval; }int myic_DESDecrypt(unsigned char *pDesKey,int nDesKeyLen,unsigned char *pInData,int nInDataLen,unsigned char *pOutData,int *pOutDataLen) {unsigned char DesKeyBuf[32];unsigned char DesDecKeyBuf[128];int DecKeyLen, KeyLen = 0;int retval = 0, loops, i;if(nInDataLen%8 != 0)return 0xEE20;if(nDesKeyLen != 8)return 0xEE20;KeyLen = nDesKeyLen;memcpy(DesKeyBuf, pDesKey, nDesKeyLen);retval = OPENCOMM_DesExpandDecKey(DesKeyBuf, KeyLen,DesDecKeyBuf, (unsigned long *)&DecKeyLen);if(retval != 0)return retval;loops = nInDataLen/8;for(i = 0; i < loops; i++){retval = OPENCOMM_DesDecRaw(DesDecKeyBuf, DecKeyLen, pInData + i*8,8, pOutData + i*8, (unsigned long *)pOutDataLen);if(retval != 0)return retval;}*pOutDataLen = nInDataLen;return retval; }//對稱明文數據打pading void CW_dataPadAdd(int tag, unsigned char *date, unsigned int dateLen, unsigned char **padDate, unsigned int *padDateLen) {int i, padLen;unsigned char *pTmp = NULL;pTmp = (unsigned char *)malloc(dateLen+24);if (pTmp == NULL){*padDate = NULL;return ;}memset(pTmp, 0, dateLen+24);memcpy(pTmp, date, dateLen);if (tag == 0){padLen = 8 - dateLen % 8;for (i=0; i<padLen; i++){pTmp[dateLen+i] = (char)padLen;}*padDateLen = dateLen + padLen;}else{padLen = 16 - dateLen % 16;for (i=0; i<padLen; i++){pTmp[dateLen+i] = (char)padLen;} }*padDateLen = dateLen + padLen; *padDate = pTmp; }#define USER_PASSWORD_KEY "abcd1234"//數據加密 int des_encode(unsigned char *pInData,int nInDataLen,unsigned char *pOutData,int *pOutDataLen) {int rv;unsigned char *padDate = NULL;unsigned int padDateLen = 0;CW_dataPadAdd(0, pInData, (unsigned int )nInDataLen, &padDate, &padDateLen);rv = myic_DESEncrypt((unsigned char *)USER_PASSWORD_KEY, strlen(USER_PASSWORD_KEY),padDate, (int)padDateLen, pOutData, pOutDataLen);if (rv != 0){if (padDate != NULL){free(padDate);}return rv; }if (padDate != NULL){free(padDate);}return 0; }//數據加密 int des_encode_raw(unsigned char *pInData,int nInDataLen,unsigned char *pOutData,int *pOutDataLen) {int rv;rv = myic_DESEncrypt((unsigned char *)USER_PASSWORD_KEY, strlen(USER_PASSWORD_KEY),pInData, (int)nInDataLen, pOutData, pOutDataLen);if (rv != 0){return rv; }return 0; }//解密分配內存錯誤 #define ERR_MALLOC 20 //密碼長度不是8的整數倍, 不合法 #define ERR_FILECONT 20//用戶使用函數des解密 int des_decode(unsigned char *pInData,int nInDataLen,unsigned char *pOutData,int *pOutDataLen) {int rv;char padChar;unsigned char *tmpPlain = NULL;tmpPlain = (unsigned char *)malloc(nInDataLen+24);if (tmpPlain == NULL){return ERR_MALLOC;}memset(tmpPlain, 0, nInDataLen+24);//解密rv = myic_DESDecrypt((unsigned char *)USER_PASSWORD_KEY, strlen(USER_PASSWORD_KEY),pInData, nInDataLen, tmpPlain, pOutDataLen);if (rv != 0){if (tmpPlain != NULL) free(tmpPlain);return rv;}//去padingpadChar = tmpPlain[*pOutDataLen - 1];if ( (int)padChar<=0 || (int)padChar>8) //異常處理{if (tmpPlain) free(tmpPlain);return ERR_FILECONT;}*pOutDataLen = *pOutDataLen - (int)padChar; //memset(tmpPlain + *pOutDataLen, 0, (int)padChar); memcpy(pOutData, tmpPlain, *pOutDataLen);if (tmpPlain) free(tmpPlain); return 0; }//用戶使用函數des解密 int des_decode_raw(unsigned char *pInData,int nInDataLen,unsigned char *pOutData,int *pOutDataLen) {int rv;//解密rv = myic_DESDecrypt((unsigned char *)USER_PASSWORD_KEY, strlen(USER_PASSWORD_KEY),pInData, nInDataLen, pOutData, pOutDataLen);if (rv != 0){return rv;}return 0; }

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