#include "os.h"#include <libsec.h> /* little-endian data order */#define	GET4(p)		((p)[0]|((p)[1]<<8)|((p)[2]<<16)|((p)[3]<<24))#define	PUT4(p,v)	(p)[0]=(v);(p)[1]=(v)>>8;(p)[2]=(v)>>16;(p)[3]=(v)>>24 static voidgf_mulx(uchar *x){	ulong t0, t1, t2, t3, t4; 	t0 = GET4(x);	t1 = GET4(x+4);	t2 = GET4(x+8);	t3 = GET4(x+12); 	t4 =             (t3 >> 31);	t3 = (t3 << 1) | (t2 >> 31);	t2 = (t2 << 1) | (t1 >> 31);	t1 = (t1 << 1) | (t0 >> 31);	t0 = (t0 << 1) ^ (t4*135); 	PUT4(x, t0);	PUT4(x+4, t1);	PUT4(x+8, t2);	PUT4(x+12, t3);} static voidxor128(uchar *o, uchar *i1, uchar *i2){	int i; 	for(i=0; i<16; i++)		o[i] = i1[i] ^ i2[i];} static voidsetupT(AESstate *tweak, uvlong sectorNumber, uchar T[AESbsize]){	PUT4(T+0, (ulong)sectorNumber), sectorNumber >>= 32;	PUT4(T+4, (ulong)sectorNumber);	PUT4(T+8, 0);	PUT4(T+12, 0);	aes_encrypt(tweak->ekey, tweak->rounds, T, T);} voidaes_xts_encrypt(AESstate *tweak, AESstate *ecb,	uvlong sectorNumber, uchar *input, uchar *output, ulong len){	uchar T[AESbsize], x[AESbsize];		if(len % AESbsize)		abort(); 	setupT(tweak, sectorNumber, T);	for (; len > 0; len -= AESbsize, input += AESbsize, output += AESbsize) {		xor128(x, input, T);		aes_encrypt(ecb->ekey, ecb->rounds, x, x);		xor128(output, x, T);		gf_mulx(T);	}} voidaes_xts_decrypt(AESstate *tweak, AESstate *ecb,	uvlong sectorNumber, uchar *input, uchar *output, ulong len){	uchar T[AESbsize], x[AESbsize];		if(len % AESbsize)		abort(); 	setupT(tweak, sectorNumber, T);	for (; len > 0; len -= AESbsize, input += AESbsize, output += AESbsize) {		xor128(x, input, T);		aes_decrypt(ecb->dkey, ecb->rounds, x, x);		xor128(output, x, T);		gf_mulx(T);	}}