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#include "os.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 voiddesECBencrypt(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];	}} voiddesECBdecrypt(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];	}}