DES加解密实现
对称加密算法包括DES、AES，其中DES算法的密钥56位（7字节）安全性较弱，于是产生3DES算法，3DES使用3个密钥，加密过程：用秘钥1进行DES加密，秘钥2进行DES解密，秘钥3进行DES加密；解密过程：用秘钥1进行DES解密，秘钥2进行DES加密，秘钥3进行DES解密。
DES加解密要求秘钥是8字节（每个字节的最后1位用于校验，秘钥是剩下的56位），加解密数据长度必须是8字节的整数倍，每8字节称为一个加解密块。如果不是8字节整数倍就要指定填充模式，常见填充模式有pkcs5padding、pkcs7padding、zeropadding。如果加解密数据包含多个块，在加解密某个块前可以指定跟前面的块进行某种计算，称为加密模式，常见有ECB和CBC。
网上有很多DES加解密的实现，但是能直接拿来使用的很少，本文介绍的是Richard Outerbridge的实现，其只实现8字节的数据加解密核心算法，对于长度不是8字节的倍数，需要填充到8的倍数，加密模式（ECB、CBC），需自己实现。它包含2个API：
第一，void deskey(unsigned char* hexkey[8], short mode)，设定DES加解密的密钥和加密还是解密的标志。
第二，void des(unsigned char* from[8], unsigned char* to[8])，DES运算，加密运算还是解密运算由deskey接口mode指定，from指定源数据，to指定运算后数据。
接下来演示如何使用DES/3DES对字符串进行加解密，本演示代码使用的填充模式为自定义格式：明文长度(2字节)+明文内容+\0填充直到8的倍数，未采用加密模式（块之间加解密独立）。演示代码包含des算法实现（d3des.h和d3des.cpp）、demo代码(main.cpp)
main.cpp
#include "stdio.h"
#include <string>
#include "d3des.h"
int main()
{
// 下面这段明文的长度是15，不是8的倍数，加密前需要先填充成8的倍数，
// 定义填充格式：明文长度(2字节)+明文内容+\0填充直到8的倍数
std::string strPlainText = "I am plain text";
int nBufferLength = 2 + strPlainText.length();
if (nBufferLength % 8 != 0)
{
nBufferLength += (8 - nBufferLength % 8);
}
unsigned char* pPlainTextBuffer = new unsigned char[nBufferLength];
memset(pPlainTextBuffer, 0, nBufferLength);
*((unsigned short*)pPlainTextBuffer) = strPlainText.length();
memcpy(pPlainTextBuffer + 2, strPlainText.c_str(), strPlainText.length());
// DES加密，然后解密验证跟明文相同
unsigned char key[8];
memcpy(key, "Iamkey1!", 8);
deskey(key, EN0); //设置秘钥，指定加密
unsigned char* pCryptTextBuffer = new unsigned char[nBufferLength];
for (int i = 0; i < nBufferLength / 8; i++)
{
des(pPlainTextBuffer + i * 8, pCryptTextBuffer + i * 8); //加密
}
deskey(key, DE1); //设置秘钥，指定解密
unsigned char* pPlainTextBuffer2 = new unsigned char[nBufferLength];
for (int i = 0; i < nBufferLength / 8; i++)
{
des(pCryptTextBuffer + i * 8, pPlainTextBuffer2 + i * 8); //解密
}
// 根据填充格式获得明文
strPlainText = std::string((const char*)(pPlainTextBuffer2 + 2), *((unsigned short*)pPlainTextBuffer2));
printf("des encrypt, then decrypt, the plain text is %s \n", strPlainText.c_str());
// 3DES加密，先用key1加密，再用key2解密，最后用key3加密
unsigned char keys[24];
memcpy(keys, "Iamkey1!Iamkey2!Iamkey3!", 24);
deskey(keys, EN0); //设置秘钥，指定加密
for (int i = 0; i < nBufferLength / 8; i++)
{
des(pPlainTextBuffer + i * 8, pCryptTextBuffer + i * 8); //加密
}
deskey(keys+8, DE1); //设置秘钥，指定解密
for (int i = 0; i < nBufferLength / 8; i++)
{
des(pCryptTextBuffer + i * 8, pCryptTextBuffer + i * 8); //解密
}
deskey(keys + 16, DE1); //设置秘钥，指定加密
for (int i = 0; i < nBufferLength / 8; i++)
{
des(pCryptTextBuffer + i * 8, pCryptTextBuffer + i * 8); //加密
}
delete[] pPlainTextBuffer;
delete[] pCryptTextBuffer;
delete[] pPlainTextBuffer2;
return 0;
}d3des.h
/* d3des.h -
*
* Headers and defines for d3des.c
* Graven Imagery, 1992.
*
* Copyright (c) 1988,1989,1990,1991,1992 by Richard Outerbridge
* (GEnie : OUTER; CIS : [71755,204])
*/
#define D2_DES /* include double-length support */
#define D3_DES /* include triple-length support */
#ifdef D3_DES
#ifndef D2_DES
#define D2_DES /* D2_DES is needed for D3_DES */
#endif
#endif
#define EN0 0 /* MODE == encrypt */
#define DE1 1 /* MODE == decrypt */
/* A useful alias on 68000-ish machines, but NOT USED HERE. */
/*
typedef union {
unsigned long blok[2];
unsigned short word[4];
unsigned char byte[8];
} M68K;*/
extern void deskey(unsigned char *, short);//得到加密/解密码(56bits)
/* hexkey[8] MODE
* Sets the internal key register according to the hexadecimal
* key contained in the 8 bytes of hexkey, according to the DES,
* for encryption or decryption according to MODE.
*/
extern void usekey(unsigned long *);
/* cookedkey[32]
* Loads the internal key register with the data in cookedkey.
*/
extern void cpkey(unsigned long *);
/* cookedkey[32]
* Copies the contents of the internal key register into the storage
* located at &cookedkey[0].
*/
extern void des(unsigned char *, unsigned char *);
/* from[8] to[8]
* Encrypts/Decrypts (according to the key currently loaded in the
* internal key register) one block of eight bytes at address 'from'
* into the block at address 'to'. They can be the same.
*/
#ifdef D2_DES
#define desDkey(a,b) des2key((a),(b))
extern void des2key(unsigned char *, short);
/* hexkey[16] MODE
* Sets the internal key registerS according to the hexadecimal
* keyS contained in the 16 bytes of hexkey, according to the DES,
* for DOUBLE encryption or decryption according to MODE.
* NOTE: this clobbers all three key registers!
*/
extern void Ddes(unsigned char *, unsigned char *);
/* from[8] to[8]
* Encrypts/Decrypts (according to the keyS currently loaded in the
* internal key registerS) one block of eight bytes at address 'from'
* into the block at address 'to'. They can be the same.
*/
extern void D2des(unsigned char *, unsigned char *);
/* from[16] to[16]
* Encrypts/Decrypts (according to the keyS currently loaded in the
* internal key registerS) one block of SIXTEEN bytes at address 'from'
* into the block at address 'to'. They can be the same.
*/
extern void makekey(char *, unsigned char *);
/* *password, single-length key[8]
* With a double-length default key, this routine hashes a NULL-terminated
* string into an eight-byte random-looking key, suitable for use with the
* deskey() routine.
*/
#define makeDkey(a,b) make2key((a),(b))
extern void make2key(char *, unsigned char *);
/* *password, double-length key[16]
* With a double-length default key, this routine hashes a NULL-terminated
* string into a sixteen-byte random-looking key, suitable for use with the
* des2key() routine.
*/
#ifndef D3_DES /* D2_DES only */
#define useDkey(a) use2key((a))
#define cpDkey(a) cp2key((a))
extern void use2key(unsigned long *);
/* cookedkey[64]
* Loads the internal key registerS with the data in cookedkey.
* NOTE: this clobbers all three key registers!
*/
extern void cp2key(unsigned long *);
/* cookedkey[64]
* Copies the contents of the internal key registerS into the storage
* located at &cookedkey[0].
*/
#else /* D3_DES too */
#define useDkey(a) use3key((a))
#define cpDkey(a) cp3key((a))
extern void des3key(unsigned char *, short);
/* hexkey[24] MODE
* Sets the internal key registerS according to the hexadecimal
* keyS contained in the 24 bytes of hexkey, according to the DES,
* for DOUBLE encryption or decryption according to MODE.
*/
extern void use3key(unsigned long *);
/* cookedkey[96]
* Loads the 3 internal key registerS with the data in cookedkey.
*/
extern void cp3key(unsigned long *);
/* cookedkey[96]
* Copies the contents of the 3 internal key registerS into the storage
* located at &cookedkey[0].
*/
extern void make3key(char *, unsigned char *);
/* *password, triple-length key[24]
* With a triple-length default key, this routine hashes a NULL-terminated
* string into a twenty-four-byte random-looking key, suitable for use with
* the des3key() routine.
*/
#endif /* D3_DES */
#endif /* D2_DES */
/* d3des.h V5.09 rwo 9208.04 15:06 Graven Imagery
********************************************************************/d3des.cpp
/* D3DES (V5.09) -
*
* A portable, public domain, version of the Data Encryption Standard.
*
* Written with Symantec's THINK (Lightspeed) C by Richard Outerbridge.
* Thanks to: Dan Hoey for his excellent Initial and Inverse permutation
* code; Jim Gillogly & Phil Karn for the DES key schedule code; Dennis
* Ferguson, Eric Young and Dana How for comparing notes; and Ray Lau,
* for humouring me on.
*
* Copyright (c) 1988,1989,1990,1991,1992 by Richard Outerbridge.
* (GEnie : OUTER; CIS : [71755,204]) Graven Imagery, 1992.
*/
#include "d3des.h"
static void scrunch(unsigned char *, unsigned long *);
static void unscrun(unsigned long *, unsigned char *);
static void desfunc(unsigned long *, unsigned long *);
static void cookey(unsigned long *);
static unsigned long KnL[32] = { 0L };
static unsigned long KnR[32] = { 0L };
static unsigned long Kn3[32] = { 0L };
static unsigned char Df_Key[24] = {
0x01,0x23,0x45,0x67,0x89,0xab,0xcd,0xef,
0xfe,0xdc,0xba,0x98,0x76,0x54,0x32,0x10,
0x89,0xab,0xcd,0xef,0x01,0x23,0x45,0x67 };
static unsigned short bytebit[8] = {
0200, 0100, 040, 020, 010, 04, 02, 01 };
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 };
/* Use the key schedule specified in the Standard (ANSI X3.92-1981). */
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 totrot[16] = {
1,2,4,6,8,10,12,14,15,17,19,21,23,25,27,28 };
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 };
void deskey(unsigned char *key, short edf) /* Thanks to James Gillogly & Phil Karn! */
{
register int i, j, l, m, n;
unsigned char pc1m[56], pcr[56];
unsigned long kn[32];
for ( j = 0; j < 56; j++ ) {
l = pc1[j];
m = l & 07;
pc1m[j] = (key[l >> 3] & 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];
}
}
cookey(kn);
return;
}
static void cookey(register unsigned long *raw1)
{
register unsigned long *cook, *raw0;
unsigned long dough[32];
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);
}
usekey(dough);
return;
}
void cpkey(register unsigned long *into)
{
register unsigned long *from, *endp;
from = KnL, endp = &KnL[32];
while( from < endp ) *into++ = *from++;
return;
}
void usekey(register unsigned long *from)
{
register unsigned long *to, *endp;
to = KnL, endp = &KnL[32];
while( to < endp ) *to++ = *from++;
return;
}
void des(unsigned char *inblock, unsigned char *outblock)
{
unsigned long work[2];
scrunch(inblock, work);
desfunc(work, KnL);
unscrun(work, outblock);
return;
}
static 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;
}
static 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;
}
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, 0x02000000L, 0x42080000L,
0x42080100L, 0x00080100L, 0x42000000L, 0x42080100L,
0x02080000L, 0x00000000L, 0x40080000L, 0x42000000L,
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 };
static 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;
}
#ifdef D2_DES
void des2key(unsigned char *hexkey, short mode) /* stomps on Kn3 too */
/* unsigned char[16] */
{
short revmod;
revmod = (mode == EN0) ? DE1 : EN0;
deskey(&hexkey[8], revmod);
cpkey(KnR);
deskey(hexkey, mode);
cpkey(Kn3); /* Kn3 = KnL */
return;
}
void Ddes(unsigned char *from, unsigned char *into)
/* unsigned char[8] */
{
unsigned long work[2];
scrunch(from, work);
desfunc(work, KnL);
desfunc(work, KnR);
desfunc(work, Kn3);
unscrun(work, into);
return;
}
void D2des(unsigned char *from, unsigned char *into)
/* unsigned char[16] */
/* unsigned char[16] */
{
unsigned long *right, *l1, swap;
unsigned long leftt[2], bufR[2];
right = bufR;
l1 = &leftt[1];
scrunch(from, leftt);
scrunch(&from[8], right);
desfunc(leftt, KnL);
desfunc(right, KnL);
swap = *l1;
*l1 = *right;
*right = swap;
desfunc(leftt, KnR);
desfunc(right, KnR);
swap = *l1;
*l1 = *right;
*right = swap;
desfunc(leftt, Kn3);
desfunc(right, Kn3);
unscrun(leftt, into);
unscrun(right, &into[8]);
return;
}
void makekey(register char *aptr, register unsigned char *kptr)
/* NULL-terminated */
/* unsigned char[8] */
{
register unsigned char *store;
register int first, i;
unsigned long savek[96];
cpDkey(savek);
des2key(Df_Key, EN0);
for( i = 0; i < 8; i++ ) kptr[i] = Df_Key[i];
first = 1;
while( (*aptr != '\0') || first ) {
store = kptr;
for( i = 0; i < 8 && (*aptr != '\0'); i++ ) {
*store++ ^= *aptr & 0x7f;
*aptr++ = '\0';
}
Ddes(kptr, kptr);
first = 0;
}
useDkey(savek);
return;
}
void make2key(register char *aptr, register unsigned char *kptr)
/* NULL-terminated */
/* unsigned char[16] */
{
register unsigned char *store;
register int first, i;
unsigned long savek[96];
cpDkey(savek);
des2key(Df_Key, EN0);
for( i = 0; i < 16; i++ ) kptr[i] = Df_Key[i];
first = 1;
while( (*aptr != '\0') || first ) {
store = kptr;
for( i = 0; i < 16 && (*aptr != '\0'); i++ ) {
*store++ ^= *aptr & 0x7f;
*aptr++ = '\0';
}
D2des(kptr, kptr);
first = 0;
}
useDkey(savek);
return;
}
#ifndef D3_DES /* D2_DES only */
#ifdef D2_DES /* iff D2_DES! */
void cp2key(register unsigned long *into)
/* unsigned long[64] */
{
register unsigned long *from, *endp;
cpkey(into);
into = &into[32];
from = KnR, endp = &KnR[32];
while( from < endp ) *into++ = *from++;
return;
}
void use2key(register unsigned long *from) /* stomps on Kn3 too */
/* unsigned long[64] */
{
register unsigned long *to, *endp;
usekey(from);
from = &from[32];
to = KnR, endp = &KnR[32];
while( to < endp ) *to++ = *from++;
cpkey(Kn3); /* Kn3 = KnL */
return;
}
#endif /* iff D2_DES */
#else /* D3_DES too */
static void D3des(unsigned char *, unsigned char *);
void des3key(unsigned char *hexkey, short mode)
/* unsigned char[24] */
{
unsigned char *first, *third;
short revmod;
if( mode == EN0 ) {
revmod = DE1;
first = hexkey;
third = &hexkey[16];
}
else {
revmod = EN0;
first = &hexkey[16];
third = hexkey;
}
deskey(&hexkey[8], revmod);
cpkey(KnR);
deskey(third, mode);
cpkey(Kn3);
deskey(first, mode);
return;
}
void cp3key(register unsigned long *into)
/* unsigned long[96] */
{
register unsigned long *from, *endp;
cpkey(into);
into = &into[32];
from = KnR, endp = &KnR[32];
while( from < endp ) *into++ = *from++;
from = Kn3, endp = &Kn3[32];
while( from < endp ) *into++ = *from++;
return;
}
void use3key(register unsigned long *from)
/* unsigned long[96] */
{
register unsigned long *to, *endp;
usekey(from);
from = &from[32];
to = KnR, endp = &KnR[32];
while( to < endp ) *to++ = *from++;
to = Kn3, endp = &Kn3[32];
while( to < endp ) *to++ = *from++;
return;
}
static void D3des(unsigned char *from, unsigned char *into) /* amateur theatrics */
/* unsigned char[24] */
/* unsigned char[24] */
{
unsigned long swap, leftt[2], middl[2], right[2];
scrunch(from, leftt);
scrunch(&from[8], middl);
scrunch(&from[16], right);
desfunc(leftt, KnL);
desfunc(middl, KnL);
desfunc(right, KnL);
swap = leftt[1];
leftt[1] = middl[0];
middl[0] = swap;
swap = middl[1];
middl[1] = right[0];
right[0] = swap;
desfunc(leftt, KnR);
desfunc(middl, KnR);
desfunc(right, KnR);
swap = leftt[1];
leftt[1] = middl[0];
middl[0] = swap;
swap = middl[1];
middl[1] = right[0];
right[0] = swap;
desfunc(leftt, Kn3);
desfunc(middl, Kn3);
desfunc(right, Kn3);
unscrun(leftt, into);
unscrun(middl, &into[8]);
unscrun(right, &into[16]);
return;
}
void make3key(register char *aptr, register unsigned char *kptr)
/* NULL-terminated */
/* unsigned char[24] */
{
register unsigned char *store;
register int first, i;
unsigned long savek[96];
cp3key(savek);
des3key(Df_Key, EN0);
for( i = 0; i < 24; i++ ) kptr[i] = Df_Key[i];
first = 1;
while( (*aptr != '\0') || first ) {
store = kptr;
for( i = 0; i < 24 && (*aptr != '\0'); i++ ) {
*store++ ^= *aptr & 0x7f;
*aptr++ = '\0';
}
D3des(kptr, kptr);
first = 0;
}
use3key(savek);
return;
}
#endif /* D3_DES */
#endif /* D2_DES */
/* Validation sets:
*
* Single-length key, single-length plaintext -
* Key : 0123 4567 89ab cdef
* Plain : 0123 4567 89ab cde7
* Cipher : c957 4425 6a5e d31d
*
* Double-length key, single-length plaintext -
* Key : 0123 4567 89ab cdef fedc ba98 7654 3210
* Plain : 0123 4567 89ab cde7
* Cipher : 7f1d 0a77 826b 8aff
*
* Double-length key, double-length plaintext -
* Key : 0123 4567 89ab cdef fedc ba98 7654 3210
* Plain : 0123 4567 89ab cdef 0123 4567 89ab cdff
* Cipher : 27a0 8440 406a df60 278f 47cf 42d6 15d7
*
* Triple-length key, single-length plaintext -
* Key : 0123 4567 89ab cdef fedc ba98 7654 3210 89ab cdef 0123 4567
* Plain : 0123 4567 89ab cde7
* Cipher : de0b 7c06 ae5e 0ed5
*
* Triple-length key, double-length plaintext -
* Key : 0123 4567 89ab cdef fedc ba98 7654 3210 89ab cdef 0123 4567
* Plain : 0123 4567 89ab cdef 0123 4567 89ab cdff
* Cipher : ad0d 1b30 ac17 cf07 0ed1 1c63 81e4 4de5
*
* d3des V5.0a rwo 9208.07 18:44 Graven Imagery
**********************************************************************/本文参与 腾讯云自媒体同步曝光计划，分享自微信公众号。
原始发表：2020-01-22，如有侵权请联系 cloudcommunity@tencent.com 删除
评论
登录后参与评论
推荐阅读
腾讯云开发者
