【C 语言】文件操作 ( 文件加密解密

文章目录

一、文件加密解密操作
- 1、解密整 4096 字节的数据
- 2、解密小于 4096 字节的数据
二、完整代码示例
- 1、文件加密操作 main.c
- 2、DES 加密解密头文件 des.h
- 3、第三方 DES 加密解密函数库源码 des.c

一、文件加密解密操作

准备 2 2 2 个文件 , 一个是原始文件 , 一个是加密后的文件 , 将原始文件进行加密 , 然后将加密后的数据输出到加密文件中 ;

    // 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";

    // 将 要加密的 input_file 文件加密 , 并输出到 output_file 文件中
    ret =  file_decode(input_file, output_file);

1、解密整 4096 字节的数据

打开输入文件 , 每次从输入文件中 , 读取 4096 4096 4096 字节数据 , 将这 4096 4096 4096 字节数据解密 , 然后写出到解密文件中 ;

    // 循环读取输入文件中的数据
    while (!feof(fp_in))
    {
        // 尝试从输入文件中读取 4K 数据
        input_len = fread(input_buffer, 1, 4096, fp_in);
        // 如果读取完毕 , 直接退出
        if (feof(fp_in))
        {
            break;
        }

        // 解密 4096 字节数据
        ret =  des_decode_raw(input_buffer, input_len, output_buffer, &output_len);
        // 如果加密失败, 直接退出
        if (ret != 0)
        {
            printf("error : des_encode_raw \n", ret);
            goto END;
        }

        // 将解密后的数据 , 写出到输出文件中
        output_tmplen = fwrite(output_buffer, 1, output_len, fp_out);
        // 如果写出失败 , 直接退出
        if (output_tmplen != output_len)
        {
            ret  = -3;
            printf("error : fwrite\n");
            goto END;
        }
    }

2、解密小于 4096 字节的数据

如果读取的数据小于 4096 4096 4096 字节 , 会退出循环 , 执行下面的业务逻辑 ;

下面的函数主要是解密小于 4096 字节数据 , 加密完成后 , 将解密数据输出到文件中 ;

    // 解密小于 4096 字节数据
    ret =  des_decode(input_buffer, input_len, output_buffer, &output_len);
    // 加密失败 , 直接退出
    if (ret != 0)
    {
        printf("error : des_decode \n", ret);
        goto END;
    }

    // 将解密后的数据 , 写出到输出文件中
    output_tmplen = fwrite(output_buffer, 1, output_len, fp_out);
    // 如果写出失败 , 直接退出
    if (output_len != output_tmplen)
    {
        ret  = -3;
        printf("error : fwrite\n");
        goto END;
    }

二、完整代码示例 1、文件加密操作 main.c

#define  _CRT_SECURE_NO_WARNINGS
#include 
#include 
#include 
#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)
{
    // 用于接收各个步骤的返回值 , 做校验
    int ret = 0;

    // 输入 文件 指针
    FILE *fp_in= NULL;

    // 输出 文件 指针
    FILE *fp_out = NULL;

    // 输入缓冲区 , 大小 4K
    unsigned char input_buffer[4096] = {0};

    // 输入数据字节数
    int input_len = 0;

    // 输出文件缓冲区
    unsigned char output_buffer[4096] = {0};

    // 输出数据字节数
    int output_len = 0;

    // 输出数据写出字节数 , 用于与上面的 output_len 进行对比
    // 一般情况下这两个值相等 , 如果出错 , 直接退出程序
    int output_tmplen;

    // 打开输入文件
    fp_in = fopen(input_file, "rb");
    if (fp_in == NULL)
    {
        goto END;
    }

    // 打开输出文件
    fp_out = fopen(output_file, "wb");
    if (fp_out == NULL)
    {
        goto END;
    }

    // 循环读取输入文件中的数据
    while (!feof(fp_in))
    {
        // 尝试从输入文件中读取 4K 数据
        input_len = fread(input_buffer, 1, 4096, fp_in);
        // 如果读取完毕 , 直接退出
        if (feof(fp_in))
        {
            break;
        }

        // 加密 4096 字节数据
        ret =  des_encode_raw(input_buffer, input_len, output_buffer, &output_len);
        // 如果加密失败, 直接退出
        if (ret != 0)
        {
            printf("error : des_encode_raw \n", ret);
            goto END;
        }

        // 将加密后的数据 , 写出到输出文件中
        output_tmplen = fwrite(output_buffer, 1, output_len, fp_out);
        // 如果写出失败 , 直接退出
        if (output_tmplen != output_len)
        {
            ret  = -3;
            printf("error : fwrite\n");
            goto END;
        }
    }

    // 加密小于 4096 字节数据
    ret =  des_encode(input_buffer, input_len, output_buffer, &output_len);
    // 加密失败 , 直接退出
    if (ret != 0)
    {
        printf("error : des_encode \n", ret);
        goto END;
    }

    // 将加密后的数据 , 写出到输出文件中
    output_tmplen = fwrite(output_buffer, 1, output_len, fp_out);
    // 如果写出失败 , 直接退出
    if (output_len != output_tmplen)
    {
        ret  = -3;
        printf("error : fwrite\n");
        goto END;
    }

END:
    // 关闭输入文件
    if (fp_in != NULL)
    {
        fclose(fp_in);
    }
    // 关闭输出文件
    if (fp_out != NULL)
    {
        fclose(fp_out);
    }
    return 0;
}

int main_encode()
{
    // 接收 子函数 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";

    // 将 要加密的 input_file 文件加密 , 并输出到 output_file 文件中
    ret =  file_encode(input_file, output_file);

    // 加密失败
    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)
{
    // 用于接收各个步骤的返回值 , 做校验
    int ret = 0;

    // 输入 文件 指针
    FILE *fp_in= NULL;

    // 输出 文件 指针
    FILE *fp_out = NULL;

    // 输入缓冲区 , 大小 4K
    unsigned char input_buffer[4096] = {0};

    // 输入数据字节数
    int input_len = 0;

    // 输出文件缓冲区
    unsigned char output_buffer[4096] = {0};

    // 输出数据字节数
    int output_len = 0;

    // 输出数据写出字节数 , 用于与上面的 output_len 进行对比
    // 一般情况下这两个值相等 , 如果出错 , 直接退出程序
    int output_tmplen;

    // 打开输入文件
    fp_in = fopen(input_file, "rb");
    if (fp_in == NULL)
    {
        goto END;
    }

    // 打开输出文件
    fp_out = fopen(output_file, "wb");
    if (fp_out == NULL)
    {
        goto END;
    }

    // 循环读取输入文件中的数据
    while (!feof(fp_in))
    {
        // 尝试从输入文件中读取 4K 数据
        input_len = fread(input_buffer, 1, 4096, fp_in);
        // 如果读取完毕 , 直接退出
        if (feof(fp_in))
        {
            break;
        }

        // 解密 4096 字节数据
        ret =  des_decode_raw(input_buffer, input_len, output_buffer, &output_len);
        // 如果加密失败, 直接退出
        if (ret != 0)
        {
            printf("error : des_encode_raw \n", ret);
            goto END;
        }

        // 将解密后的数据 , 写出到输出文件中
        output_tmplen = fwrite(output_buffer, 1, output_len, fp_out);
        // 如果写出失败 , 直接退出
        if (output_tmplen != output_len)
        {
            ret  = -3;
            printf("error : fwrite\n");
            goto END;
        }
    }

    // 解密小于 4096 字节数据
    ret =  des_decode(input_buffer, input_len, output_buffer, &output_len);
    // 加密失败 , 直接退出
    if (ret != 0)
    {
        printf("error : des_decode \n", ret);
        goto END;
    }

    // 将解密后的数据 , 写出到输出文件中
    output_tmplen = fwrite(output_buffer, 1, output_len, fp_out);
    // 如果写出失败 , 直接退出
    if (output_len != output_tmplen)
    {
        ret  = -3;
        printf("error : fwrite\n");
        goto END;
    }

END:
    // 关闭输入文件
    if (fp_in != NULL)
    {
        fclose(fp_in);
    }
    // 关闭输出文件
    if (fp_out != NULL)
    {
        fclose(fp_out);
    }
    return 0;
}


int main_decode()
{
    // 接收 子函数 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";

    // 将 要加密的 input_file 文件加密 , 并输出到 output_file 文件中
    ret =  file_decode(input_file, output_file);

    // 加密失败
    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 加密解密头文件 des.h

/*********************************************************
 *  des.h
 *  DES 加密算法头文件
 *********************************************************/
#ifndef _DES_H_
#define _DES_H_

#ifdef __cplusplus
extern "C" {
#endif

/**
 * @brief des_encode_raw DES 加密操作 , 加密 4096 字节数据
 * @param in_data 输入数据
 * @param in_data_len 输入数据长度
 * @param out_data 输出数据
 * @param out_data_len 输出数据长度
 * @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 字节数据
 * @param in_data 输入数据
 * @param in_data_len 输入数据长度
 * @param out_data 输出数据
 * @param out_data_len 输出数据长度
 * @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 字节
 * @param in_data 输入数据
 * @param in_data_len 输入数据长度
 * @param out_data 输出数据
 * @param out_data_len 输出数据长度
 * @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 字节
 * @param in_data 输入数据
 * @param in_data_len 输入数据长度
 * @param out_data 输出数据
 * @param out_data_len 输出数据长度
 * @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 加密解密函数库源码 des.c

/******************************************************
 *
 *  des.c
 *  common des......
 *
 ******************************************************/

#include 
#include 
#include 
#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	8

typedef 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 > 3] & (unsigned long)bytebit[m] ) ? 1:0);
	}
	for ( i = 0;i   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  1);
	work = (leftt ^ right) & 0xaaaaaaaaL;
	leftt ^= work;
	right ^= work;
	leftt = (leftt  1);
	work = ((leftt >>  8) ^ right) & 0x00ff00ffL;
	right ^= work;
	leftt ^= (work   2) ^ right) & 0x33333333L;
	right ^= work;
	leftt ^= (work  16) ^ leftt) & 0x0000ffffL;
	leftt ^= work;
	right ^= (work   4) ^ leftt) & 0x0f0f0f0fL;
	leftt ^= work;
	right ^= (work  8 bytes
	memcpy(pbOutData, cp, DES_BLOCKLEN);
	*ulOutDataLen = DES_BLOCKLEN;

	return 0;
}

/*****************************************************************
	OPENCOMM_DesDecRaw : Des算法解密小整块密文8字节 
	Return value:
		0     : Success
		other : failed
	Parameters:
		pbDesDecKey    : DES解密密钥     input
		ulDesDecKeyLen : DES解密密钥长度  input
		pbInData       : 待解密的密文     input
		ulInDataLen    : 待解密的密文长度  input
		pbOutData      : 解密后的明文     output
		*ulOutDataLen  : 解密后的明文长度  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 long
	memcpy(dk, pbDesDecKey, ulDesDecKeyLen);
	desfunc(work,dk);
	unscrun(work,cp); // 2 long -> 8 bytes
	memcpy(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

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