【C 语言】文件操作 ( 文件加密解密 | 解密文件 )(二)

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简介: 【C 语言】文件操作 ( 文件加密解密 | 解密文件 )(二)

3、第三方 DES 加密解密函数库源码 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  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 < 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 扩展des加密密钥
  Return value:
  0         : Success
  other     : failed
  Parameters:
  pbDesKey        : 扩展前的DES密钥(8字节)       input
  ulDesKeyLen     : 扩展前的DES密钥长度          input
  pbDesEncKey     : 扩展后的DES加密密钥(128字节)  output
  *ulDesEncKeyLen : 扩展后的DES加密密钥长度       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 bytes
  memcpy(pbDesEncKey, dough, *ulDesEncKeyLen);
  return 0;
}
/*****************************************************************
  OPENCOMM_DesExpandDecKey  : Expand Des Dec Key 扩展des解密密钥
  Return value:
  0       : Success
  other   : failed
  Parameters:
  pbDesKey        : 扩展前的DES密钥(8字节)      input
  ulDesKeyLen     : 扩展前的DES密钥长度         input
  pbDesDecKey     : 扩展后的DES解密密钥(128字节) output
  *ulDesDecKeyLen : 扩展后的DES解密密钥长度      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 bytes
  memcpy(pbDesDecKey, dough, *ulDesDecKeyLen);
  return 0;
}
/****************************************************************
  OPENCOMM_DesEncRaw  : Des算法加密小整块明文8字节 
  Return value:
  0       : Success
  other   : failed
  Parameters:
  pbDesEncKey    : DES加密密钥    input
  ulDesEncKeyLen : DES加密密钥长度 input
  pbInData       : 待加密的明文    input
  ulInDataLen    : 待加密的明文长度 input
  pbOutData      : 加密后的密文    output
  *ulOutDataLen  : 加密后的密文长度 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 long
  memcpy(ek, pbDesEncKey, ulDesEncKeyLen);
  desfunc(work,ek);
  unscrun(work,cp); // 2 long -> 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 < 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;
}
//对称明文数据打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"
//数据加密
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;
}
//数据加密
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;
}
//解密分配内存错误
#define  ERR_MALLOC 20
//密码长度不是8的整数倍, 不合法
#define  ERR_FILECONT 20
//用户使用函数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pading
  padChar = tmpPlain[*pOutDataLen - 1];
  if ( (int)padChar<=0 || (int)padChar>8) //异常处理
  {
  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;
}
//用户使用函数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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