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#include "os.h"#include <libsec.h> typedef ulong u32; voidaesCFBencrypt(uchar *p, int len, AESstate *s){	u32 a, o = s->offset; 	while(len > 0){		if(o % 16){		Odd:			a = (s->ivec[o++ % 16] ^= *p), *p++ = a, len--;			continue;		}		aes_encrypt(s->ekey, s->rounds, s->ivec, s->ivec);		if(len < 16 || ((p-(uchar*)0) & 3) != 0)			goto Odd;		((u32*)p)[0] = (((u32*)s->ivec)[0] ^= ((u32*)p)[0]);		((u32*)p)[1] = (((u32*)s->ivec)[1] ^= ((u32*)p)[1]);		((u32*)p)[2] = (((u32*)s->ivec)[2] ^= ((u32*)p)[2]);		((u32*)p)[3] = (((u32*)s->ivec)[3] ^= ((u32*)p)[3]);		o += 16, p += 16, len -= 16;	}	s->offset = o;} voidaesCFBdecrypt(uchar *p, int len, AESstate *s){	u32 a, o = s->offset; 	while(len > 0){		if(o % 16){		Odd:			a = *p, *p++ ^= s->ivec[o % 16], s->ivec[o++ % 16] = a, len--;			continue;		}		aes_encrypt(s->ekey, s->rounds, s->ivec, s->ivec);		if(len < 16 || ((p-(uchar*)0) & 3) != 0)			goto Odd;		a = ((u32*)p)[0], ((u32*)p)[0] ^= ((u32*)s->ivec)[0], ((u32*)s->ivec)[0] = a;		a = ((u32*)p)[1], ((u32*)p)[1] ^= ((u32*)s->ivec)[1], ((u32*)s->ivec)[1] = a;		a = ((u32*)p)[2], ((u32*)p)[2] ^= ((u32*)s->ivec)[2], ((u32*)s->ivec)[2] = a;		a = ((u32*)p)[3], ((u32*)p)[3] ^= ((u32*)s->ivec)[3], ((u32*)s->ivec)[3] = a;		o += 16, p += 16, len -= 16;	}	s->offset = o;}