DES加密算法Word文件下载.docx

1、failed. int encrypt （ char key8, char* data, int blocks = 1 ）; int decrypt （ char key8, char* data, int blocks = 1 ）; / Encrypt/decrypt any size data,according to a special method. / Before calling yencrypt, copy data to a new buffer with size / calculated by extend. int yencrypt （ char key8, char*

2、data, int size ）; int ydecrypt （ char key8, char* in, int blocks, int* size = 0 ）; int extend （ int size ） return （size/8+1）*8; ;private: void des（unsigned char* in, unsigned char* out, int blocks）; void des_block（unsigned char* in, unsigned char* out）; unsigned long KnL32; enum Mode ENCRYPT, DECRYP

3、T ; void deskey（unsigned char key8, Mode md）; void usekey（unsigned long *）; void cookey（unsigned long *）; void scrunch（unsigned char *, unsigned long *）; void unscrun（unsigned long *, unsigned char *）; void desfunc（unsigned long *, unsigned long *）; static unsigned char Df_Key24; static unsigned sho

4、rt bytebit8; static unsigned long bigbyte24; static unsigned char pc156; static unsigned char totrot16; static unsigned char pc248; static unsigned long SP164; static unsigned long SP264; static unsigned long SP364; static unsigned long SP464; static unsigned long SP564; static unsigned long SP664;

5、static unsigned long SP764; static unsigned long SP864;#endif #include #include des.hint DES:encrypt （ char key8, char* data, int blocks ） if （!data）|（blocks1） return 0; deskey （ key, ENCRYPT ）; des （ data, data, blocks）; return 1;decrypt （ char key8, char* data, int blocks ） deskey （ key, DECRYPT ）

6、;yencrypt （ char key8, char* data, int size ） data）|（size / The last char of data is bitwise complemented and filled the rest / buffer.If size is 16, it will extend to 24,and 17 still 24. char lastChar = *（data+size-1）; int blocks = size/8+1; memset （data+size, lastChar, blocks*8-size）; return encry

7、pt （ data, data, blocks）;ydecrypt （ char key8, char* data, int blocks, int* size ） if （ （!data） | （blocks0）&（datapos=endChar） pos-; if （ datapos != endChar ） *size = pos+1; / - / des / Encrpts/Decrypts（according to the key currently loaded int the / internal key register） SOME blocks of eight bytes

8、at address in/ into the block at address out. They can be the same. / / inoutblock Number of blocks. void DES:des （ unsigned char* in, unsigned char* out, int blocks ） for （int i = 0; i blocks; i+,in+=8,out+=8） des_block（in,out）;/ des_block / internal key register） one block of eight bytes at addres

9、s des_block（unsigned char *in, unsigned char *out） unsigned long work2; scrunch（in, work）; desfunc（work, KnL）; unscrun（work, out）; / - / deskey / Sets the internal key register （KnR） according to the hexadecimal / key contained in the 8 bytes of hexkey, according to the DES, / for encryption or decr

10、ytion according to MODE is the 64 bits key. md means encryption or decryption. deskey（unsigned char key8, Mode md） /* Thanks to James Gillogly &am p; Phil Karn! */ register int i, j, l, m, n; unsigned char pc1m56, pcr56; unsigned long kn32; for （j = 0; j 3 & bytebitm） ? 1:0; for （i = 0; 16; i+） if （

11、md = DECRYPT） m = （15 - i） 1; else m = i n = m + 1; knm = knn = 0L; 28; l = j + totroti; if （l 28） pcrj = pc1ml; else pcrj = pc1ml - 28; for （j = 28; 56） pcrj = pc1ml; 24; if （pcr pc2j ） knm |= bigbytej; if （pcr pc2j+24 ） knn |= bigbytej; cookey（kn）; return;/ cookey / Only called by deskey. cookey（r

12、egister unsigned long *raw1） register unsigned long *cook, *raw0; unsigned long dough32; register int i; cook = dough; i+, raw1+） raw0 = raw1+; *cook = （*raw0 & 0x00fc0000L） 6; *cook |= （*raw0 & 0x00000fc0L） *cook+ |= （*raw1 & 0x00000fc0L） 0x0003f000L） 12; 0x0000003fL） 4; 0x0000003fL）; usekey（dough）

13、;/ usekey / Only called by cookey. / Loads the interal key register with the data in cookedkey. usekey（register unsigned long *from） register unsigned long *to, *endp; to = KnL, endp = &KnL32; while （to endp） *to+ = *from+;scrunch（register unsigned char *outof, register unsigned long *int o ） *into

14、= （*outof+ & 0xffL） 24） & 0xffL; 16） & 8） & *into+ = *outof+ & *into = *outof &desfunc（register unsigned long *block,register unsigned long *keys ） register unsigned long fval, work, right, leftt; register int round; leftt = block0; right = block1; work = （leftt 4） right） & 0x0f0f0f0fL; right = work

15、; leftt = （work 2） leftt） & 0x33333333L; leftt = work; right = （work 2）; 8） leftt） & 0x00ff00ffL; 8）; right = （right 31） & 1L） & 0xffffffffL; work = （leftt right） & 0xaaaaaaaaL; leftt = （leftt for （round = 0; round round+） work = （right work = *keys+; fval = SP7work & 0x3fL; fval |= SP5（work fval |=

16、 SP3（work fval |= SP1（work work = right *keys+; fval |= SP8work & fval |= SP6（work fval |= SP4（work fval |= SP2（work leftt = fval; work = （leftt work = leftt *keys+; right = fval; right = （right 1）; leftt = （leftt 8） right） & 2） right） & 16） leftt） & 4） leftt） & *block+ = right; *block = leftt;/ Initial of static data members. These data will be used by all the / in