Keeloq 编解码测试

参考资料：

http://en.wikipedia.org/wiki/KeeLoq

http://cryptolib.com/ciphers/keeloq/

测试程序：

#include <stdio.h>

#include <stdlib.h>


typedef unsigned long u32;
typedef unsigned long long u64;


/*\
 *  Corrected KeeLoq Encryption and Decryption functions by Ruptor.
 *  Use at your own risk! This source is not copyrighted.
 *  Encoder encrypts an all-0 block, decoder decrypts it.
 *  KeeLoq cipher encrypts 32-bit blocks with 64-bit keys.
 *  Key is XORed with a 32-bit IV incremented on each use.
 *  See http://www.keeloq.boom.ru/decryption.pdf for more details.
 *  KeeLoq algorithm itself is not patented.
\*/


#define KeeLoq_NLF 0x3A5C742E
#define bit(x,n) (((x)>>(n))&1)
#define g5(x,a,b,c,d,e) (bit(x,a)+bit(x,b)*2+bit(x,c)*4+bit(x,d)*8+bit(x,e)*16)


u32 KeeLoq_Encrypt (const u32 data, const u64 key)
{
u32 x = data, r,u1,u2,u3,u4,u5,u0;

for (r = 0; r < 528; r++)
{
x = (x>>1)^((bit(x,0)^bit(x,16)^(u32)bit(key,r&63)^bit(KeeLoq_NLF,g5(x,1,9,20,26,31)))<<31);
}
printf("Encrypt in:%08x,out:%08x\n",data,x);
return x;
}


u32 KeeLoq_Decrypt (const u32 data, const u64 key)
{
u32 x = data, r;

for (r = 0; r < 528; r++)
{
x = (x<<1)^bit(x,31)^bit(x,15)^(u32)bit(key,(15-r)&63)^bit(KeeLoq_NLF,g5(x,0,8,19,25,30));
}
printf("Decrypt in:%08x,out:%08x\n",data,x);
return x;
}

int main(int argc, char *argv[])
{
    u32 data = 0x76543210;
    u64 key = 0x0123456789abcdef;
    u32 dataEc;
    u32 dataDc;
   
    dataEc = KeeLoq_Encrypt(data,key);
    dataDc = KeeLoq_Decrypt(dataEc,key);

    system("PAUSE");
    return EXIT_SUCCESS;

}