drawterm/libsec/desECB.c

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2005-08-08 14:50:13 +02:00
#include "os.h"
#include <mp.h>
#include <libsec.h>
// I wasn't sure what to do when the buffer was not
// a multiple of 8. I did what lacy's cryptolib did
// to be compatible, but it looks dangerous to me
// since its encrypting plain text with the key. -- presotto
void
desECBencrypt(uchar *p, int len, DESstate *s)
{
int i;
uchar tmp[8];
for(; len >= 8; len -= 8){
block_cipher(s->expanded, p, 0);
p += 8;
}
if(len > 0){
for (i=0; i<8; i++)
tmp[i] = i;
block_cipher(s->expanded, tmp, 0);
for (i = 0; i < len; i++)
p[i] ^= tmp[i];
}
}
void
desECBdecrypt(uchar *p, int len, DESstate *s)
{
int i;
uchar tmp[8];
for(; len >= 8; len -= 8){
block_cipher(s->expanded, p, 1);
p += 8;
}
if(len > 0){
for (i=0; i<8; i++)
tmp[i] = i;
block_cipher(s->expanded, tmp, 0);
for (i = 0; i < len; i++)
p[i] ^= tmp[i];
}
}