void DES_ecb3_encrypt(const unsigned char *input, unsigned char *output, 
                             DES_key_schedule *ks1,DES_key_schedule *ks2,
                             DES_key_schedule *ks3, int enc);
 
void DES_ede3_cfb_encrypt(const unsigned char *in,unsigned char *out, 
                                int numbits,long length,DES_key_schedule *ks1,
                                DES_key_schedule *ks2,DES_key_schedule *ks3,
                                DES_cblock *ivec,int enc);