des加密c语言实现源代码

《des加密c语言实现源代码》由会员上传分享，免费在线阅读，更多相关内容在应用文档-天天文库。

1、实用标准文案void*memcpy(void*dest,constvoid*src,unsignedcharcount){//ASSERT((dest!=NULL)&&(src!=NULL));unsignedchar*temp_dest=(unsignedchar*)dest;unsignedchar*temp_src=(unsignedchar*)src;while(count--)//不对是否存在重叠区域进行判断{*temp_dest++=*temp_src++;}returndest;}unsignedchar*memset(uns

2、ignedchar*dst,unsignedcharvalue,unsignedcharcount){unsignedchar*start=dst;while(count--)*dst++=value;return(start);}//初始置换表IPunsignedcharIP_Table[64]={57,49,41,33,25,17,9,1,59,51,43,35,27,19,11,3,61,53,45,37,29,21,13,5,63,55,47,39,31,23,15,7,56,48,40,32,24,16,8,0,58,50,42,

3、34,26,18,10,2,60,52,44,36,28,20,12,4,62,54,46,38,30,22,14,6};//逆初始置换表IP^-1unsignedcharIP_1_Table[64]={39,7,47,15,55,23,63,31,38,6,46,14,54,22,62,30,文档实用标准文案37,5,45,13,53,21,61,29,36,4,44,12,52,20,60,28,35,3,43,11,51,19,59,27,34,2,42,10,50,18,58,26,33,1,41,9,49,17,57,25,32,

4、0,40,8,48,16,56,24};//扩充置换表EunsignedcharE_Table[48]={31,0,1,2,3,4,3,4,5,6,7,8,7,8,9,10,11,12,11,12,13,14,15,16,15,16,17,18,19,20,19,20,21,22,23,24,23,24,25,26,27,28,27,28,29,30,31,0};//置换函数PunsignedcharP_Table[32]={15,6,19,20,28,11,27,16,0,14,22,25,4,17,30,9,1,7,23,13,31,2

5、6,2,8,18,12,29,5,21,10,3,24};//S盒文档实用标准文案unsignedcharS[8][4][16]=//S1{{{14,4,13,1,2,15,11,8,3,10,6,12,5,9,0,7},{0,15,7,4,14,2,13,1,10,6,12,11,9,5,3,8},{4,1,14,8,13,6,2,11,15,12,9,7,3,10,5,0},{15,12,8,2,4,9,1,7,5,11,3,14,10,0,6,13}},//S2{{15,1,8,14,6,11,3,4,9,7,2,13,12,0,5,

6、10},{3,13,4,7,15,2,8,14,12,0,1,10,6,9,11,5},{0,14,7,11,10,4,13,1,5,8,12,6,9,3,2,15},{13,8,10,1,3,15,4,2,11,6,7,12,0,5,14,9}},//S3{{10,0,9,14,6,3,15,5,1,13,12,7,11,4,2,8},{13,7,0,9,3,4,6,10,2,8,5,14,12,11,15,1},{13,6,4,9,8,15,3,0,11,1,2,12,5,10,14,7},{1,10,13,0,6,9,8,7,4,15

7、,14,3,11,5,2,12}},//S4{{7,13,14,3,0,6,9,10,1,2,8,5,11,12,4,15},{13,8,11,5,6,15,0,3,4,7,2,12,1,10,14,9},{10,6,9,0,12,11,7,13,15,1,3,14,5,2,8,4},{3,15,0,6,10,1,13,8,9,4,5,11,12,7,2,14}},//S5{{2,12,4,1,7,10,11,6,8,5,3,15,13,0,14,9},文档实用标准文案{14,11,2,12,4,7,13,1,5,0,15,10,3,9,8

8、,6},{4,2,1,11,10,13,7,8,15,9,12,5,6,3,0,14},{11,8,12,7,1,14,2,13,6,15,0,9,10,4,5,3}},//S6