/*
* AES-NI support functions
*
* Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
* SPDX-License-Identifier: Apache-2.0
*
* Licensed under the Apache License, Version 2.0 (the "License"); you may
* not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
* This file is part of mbed TLS (https://tls.mbed.org)
*/
/*
* [AES-WP] http://software.intel.com/en-us/articles/intel-advanced-encryption-standard-aes-instructions-set
* [CLMUL-WP] http://software.intel.com/en-us/articles/intel-carry-less-multiplication-instruction-and-its-usage-for-computing-the-gcm-mode/
*/
#if !defined(MBEDTLS_CONFIG_FILE)
#include "mbedtls/config.h"
#else
#include MBEDTLS_CONFIG_FILE
#endif
#if defined(MBEDTLS_AESNI_C)
#if defined(__has_feature)
#if __has_feature(memory_sanitizer)
#warning "MBEDTLS_AESNI_C is known to cause spurious error reports with some memory sanitizers as they do not understand the assembly code."
#endif
#endif
#include "mbedtls/aesni.h"
#include <string.h>
#ifndef asm
#define asm __asm
#endif
#if defined(MBEDTLS_HAVE_X86_64)
/*
* AES-NI support detection routine
*/
int mbedtls_aesni_has_support( unsigned int what )
{
static int done = 0;
static unsigned int c = 0;
if( ! done )
{
asm( "movl $1, %%eax \n\t"
"cpuid \n\t"
: "=c" (c)
:
: "eax", "ebx", "edx" );
done = 1;
}
return( ( c & what ) != 0 );
}
/*
* Binutils needs to be at least 2.19 to support AES-NI instructions.
* Unfortunately, a lot of users have a lower version now (2014-04).
* Emit bytecode directly in order to support "old" version of gas.
*
* Opcodes from the Intel architecture reference manual, vol. 3.
* We always use registers, so we don't need prefixes for memory operands.
* Operand macros are in gas order (src, dst) as opposed to Intel order
* (dst, src) in order to blend better into the surrounding assembly code.
*/
#define AESDEC ".byte 0x66,0x0F,0x38,0xDE,"
#define AESDECLAST ".byte 0x66,0x0F,0x38,0xDF,"
#define AESENC ".byte 0x66,0x0F,0x38,0xDC,"
#define AESENCLAST ".byte 0x66,0x0F,0x38,0xDD,"
#define AESIMC ".byte 0x66,0x0F,0x38,0xDB,"
#define AESKEYGENA ".byte 0x66,0x0F,0x3A,0xDF,"
#define PCLMULQDQ ".byte 0x66,0x0F,0x3A,0x44,"
#define xmm0_xmm0 "0xC0"
#define xmm0_xmm1 "0xC8"
#define xmm0_xmm2 "0xD0"
#define xmm0_xmm3 "0xD8"
#define xmm0_xmm4 "0xE0"
#define xmm1_xmm0 "0xC1"
#define xmm1_xmm2 "0xD1"
/*
* AES-NI AES-ECB block en(de)cryption
*/
int mbedtls_aesni_crypt_ecb( mbedtls_aes_context *ctx,
int mode,
const unsigned char input[16],
unsigned char output[16] )
{
asm( "movdqu (%3), %%xmm0 \n\t" // load input
"movdqu (%1), %%xmm1 \n\t" // load round key 0
"pxor %%xmm1, %%xmm0 \n\t" // round 0
"add $16, %1 \n\t" // point to next round key
"subl $1, %0 \n\t" // normal rounds = nr - 1
"test %2, %2 \n\t" // mode?
"jz 2f \n\t" // 0 = decrypt
"1: \n\t" // encryption loop
"movdqu (%1), %%xmm1 \n\t" // load round key
AESENC xmm1_xmm0 "\n\t" // do round
"add $16, %1 \n\t" // point to next round key
"subl $1, %0 \n\t" // loop
"jnz 1b \n\t"
"movdqu (%1), %%xmm1 \n\t" // load round key
AESENCLAST xmm1_xmm0 "\n\t" // last round
"jmp 3f \n\t"
"2: \n\t" // decryption loop
"movdqu (%1), %%xmm1 \n\t"
AESDEC xmm1_xmm0 "\n\t" // do round
"add $16, %1 \n\t"
"subl $1, %0 \n\t"
"jnz 2b \n\t"
"movdqu (%1), %%xmm1 \n\t" // load round key
AESDECLAST xmm1_xmm0 "\n\t" // last round
"3: \n\t"
"movdqu %%xmm0, (%4) \n\t" // export output
:
: "r" (ctx->nr), "r" (ctx->rk), "r" (mode), "r" (input), "r" (output)
: "memory", "cc", "xmm0", "xmm1" );
return( 0 );
}
/*
* GCM multiplication: c = a times b in GF(2^128)
* Based on [CLMUL-WP] algorithms 1 (with equation 27) and 5.
*/
void mbedtls_aesni_gcm_mult( unsigned char c[16],
const unsigned char a[16],
const unsigned char b[16] )
{
unsigned char aa[16], bb[16], cc[16];
size_t i;
/* The inputs are in big-endian order, so byte-reverse them */
for( i = 0; i < 16; i++ )
{
aa[i] = a[15 - i];
bb[i] = b[15 - i];
}
asm( "movdqu (%0), %%xmm0 \n\t" // a1:a0
"movdqu (%1), %%xmm1 \n\t" // b1:b0
/*
* Caryless multiplication xmm2:xmm1 = xmm0 * xmm1
* using [CLMUL-WP] algorithm 1 (p. 13).
*/
"movdqa %%xmm1, %%xmm2 \n\t" // copy of b1:b0
"movdqa %%xmm1, %%xmm3 \n\t" // same
"movdqa %%xmm1, %%xmm4 \n\t" // same
PCLMULQDQ xmm0_xmm1 ",0x00 \n\t" // a0*b0 = c1:c0
PCLMULQDQ xmm0_xmm2 ",0x11 \n\t" // a1*b1 = d1:d0
PCLMULQDQ xmm0_xmm3 ",0x10 \n\t" // a0*b1 = e1:e0
PCLMULQDQ xmm0_xmm4 ",0x01 \n\t" // a1*b0 = f1:f0
"pxor %%xmm3, %%xmm4 \n\t" // e1+f1:e0+f0
"movdqa %%xmm4, %%xmm3 \n\t" // same
"psrldq $8, %%xmm4 \n\t" // 0:e1+f1
"pslldq $8, %%xmm3 \n\t" // e0+f0:0
"pxor %%xmm4, %%xmm2 \n\t" // d1:d0+e1+f1
"pxor %%xmm3, %%xmm1 \n\t" // c1+e0+f1:c0
/*
* Now shift the result one bit to the left,
* taking advantage of [CLMUL-WP] eq 27 (p. 20)
*/
"movdqa %%xmm1, %%xmm3 \n\t" // r1:r0
"movdqa %%xmm2, %%xmm4 \n\t" // r3:r2
"psllq $1, %%xmm1 \n\t" // r1<<1:r0<<1
"psllq $1, %%xmm2 \n\t" // r3<<1:r2<<1
"psrlq $63, %%xmm3 \n\t" // r1>>63:r0>>63
"psrlq $63, %%xmm4 \n\t" // r3>>63:r2>>63
"movdqa %%xmm3, %%xmm5 \n\t" // r1>>63:r0>>63
"pslldq $8, %%xmm3 \n\t" // r0>>63:0
"pslldq $8, %%xmm4 \n\t" // r2>>63:0
"psrldq $8, %%xmm5 \n\t" // 0:r1>>63
"por %%xmm3, %%xmm1 \n\t" // r1<<1|r0>>63:r0<<1
"por %%xmm4, %%xmm2 \n\t" // r3<<1|r2>>62:r2<<1
"por %%xmm5, %%xmm2 \n\t" // r3<<1|r2>>62:r2<<1|r1>>63
/*
* Now reduce modulo the GCM polynomial x^128 + x^7 + x^2 + x + 1
* using [CLMUL-WP] algorithm 5 (p. 20).
* Currently xmm2:xmm1 holds x3:x2:x1:x0 (already shifted).
*/
/* Step 2 (1) */
"movdqa %%xmm1, %%xmm3 \n\t" // x1:x0
"movdqa %%xmm1, %%xmm4 \n\t" // same
"movdqa %%xmm1, %%xmm5 \n\t" // same
"psllq $63, %%xmm3 \n\t" // x1<<63:x0<<63 = stuff:a
"psllq $62, %%xmm4 \n\t" // x1<<62:x0<<62 = stuff:b
"psllq $57, %%xmm5 \n\t" // x1<<57:x0<<57 = stuff:c
/* Step 2 (2) */
"pxor %%xmm4, %%xmm3 \n\t" // stuff:a+b
"pxor %%xmm5, %%xmm3 \n\t" // stuff:a+b+c
"pslldq $8, %%xmm3 \n\t" // a+b+c:0
"pxor %%xmm3, %%xmm1 \n\t" // x1+a+b+c:x0 = d:x0
/* Steps 3 and 4 */
"movdqa %%xmm1,%%xmm0 \n\t" // d:x0
"movdqa %%xmm1,%%xmm4 \n\t" // same
"movdqa %%xmm1,%%xmm5 \n\t" // same
"psrlq $1, %%xmm0 \n\t" // e1:x0>>1 = e1:e0'
"psrlq $2, %%xmm4 \n\t" // f1:x0>>2 = f1:f0'
"psrlq $7, %%xmm5 \n\t" // g1:x0>>7 = g1:g0'
"pxor %%xmm4, %%xmm0 \n\t" // e1+f1:e0'+f0'
"pxor %%xmm5, %%xmm0 \n\t" // e1+f1+g1:e0'+f0'+g0'
// e0'+f0'+g0' is almost e0+f0+g0, ex\tcept for some missing
// bits carried from d. Now get those\t bits back in.
"movdqa %%xmm1,%%xmm3 \n\t" // d:x0
"movdqa %%xmm1,%%xmm4 \n\t" // same
"movdqa %%xmm1,%%xmm5 \n\t" // same
"psllq $63, %%xmm3 \n\t" // d<<63:stuff
"psllq $62, %%xmm4 \n\t" // d<<62:stuff
"psllq $57, %%xmm5 \n\t" // d<<57:stuff
"pxor %%xmm4, %%xmm3 \n\t" // d<<63+d<<62:stuff
"pxor %%xmm5, %%xmm3 \n\t" // missing bits of d:stuff
"psrldq $8, %%xmm3 \n\t" // 0:missing bits of d
"pxor %%xmm3, %%xmm0 \n\t" // e1+f1+g1:e0+f0+g0
"pxor %%xmm1, %%xmm0 \n\t" // h1:h0
"pxor %%xmm2, %%xmm0 \n\t" // x3+h1:x2+h0
"movdqu %%xmm0, (%2) \n\t" // done
:
: "r" (aa), "r" (bb), "r" (cc)
: "memory", "cc", "xmm0", "xmm1", "xmm2", "xmm3", "xmm4", "xmm5" );
/* Now byte-reverse the outputs */
for( i = 0; i < 16; i++ )
c[i] = cc[15 - i];
return;
}
/*
* Compute decryption round keys from encryption round keys
*/
void mbedtls_aesni_inverse_key( unsigned char *invkey,
const unsigned char *fwdkey, int nr )
{
unsigned char *ik = invkey;
const unsigned char *fk = fwdkey + 16 * nr;
memcpy( ik, fk, 16 );
for( fk -= 16, ik += 16; fk > fwdkey; fk -= 16, ik += 16 )
asm( "movdqu (%0), %%xmm0 \n\t"
AESIMC xmm0_xmm0 "\n\t"
"movdqu %%xmm0, (%1) \n\t"
:
: "r" (fk), "r" (ik)
: "memory", "xmm0" );
memcpy( ik, fk, 16 );
}
/*
* Key expansion, 128-bit case
*/
static void aesni_setkey_enc_128( unsigned char *rk,
const unsigned char *key )
{
asm( "movdqu (%1), %%xmm0 \n\t" // copy the original key
"movdqu %%xmm0, (%0) \n\t" // as round key 0
"jmp 2f \n\t" // skip auxiliary routine
/*
* Finish generating the next round key.
*
* On entry xmm0 is r3:r2:r1:r0 and xmm1 is X:stuff:stuff:stuff
* with X = rot( sub( r3 ) ) ^ RCON.
*
* On exit, xmm0 is r7:r6:r5:r4
* with r4 = X + r0, r5 = r4 + r1, r6 = r5 + r2, r7 = r6 + r3
* and those are written to the round key buffer.
*/
"1: \n\t"
"pshufd $0xff, %%xmm1, %%xmm1 \n\t" // X:X:X:X
"pxor %%xmm0, %%xmm1 \n\t" // X+r3:X+r2:X+r1:r4
"pslldq $4, %%xmm0 \n\t" // r2:r1:r0:0
"pxor %%xmm0, %%xmm1 \n\t" // X+r3+r2:X+r2+r1:r5:r4
"pslldq $4, %%xmm0 \n\t" // etc
"pxor %%xmm0, %%xmm1 \n\t"
"pslldq $4, %%xmm0 \n\t"
"pxor %%xmm1, %%xmm0 \n\t" // update xmm0 for next time!
"add $16, %0 \n\t" // point to next round key
"movdqu %%xmm0, (%0) \n\t" // write it
"ret \n\t"
/* Main "loop" */
"2: \n\t"
AESKEYGENA xmm0_xmm1 ",0x01 \n\tcall 1b \n\t"
AESKEYGENA xmm0_xmm1 ",0x02 \n\tcall 1b \n\t"
AESKEYGENA xmm0_xmm1 ",0x04 \n\tcall 1b \n\t"
AESKEYGENA xmm0_xmm1 ",0x08 \n\tcall 1b \n\t"
AESKEYGENA xmm0_xmm1 ",0x10 \n\tcall 1b \n\t"
AESKEYGENA xmm0_xmm1 ",0x20 \n\tcall 1b \n\t"
AESKEYGENA xmm0_xmm1 ",0x40 \n\tcall 1b \n\t"
AESKEYGENA xmm0_xmm1 ",0x80 \n\tcall 1b \n\t"
AESKEYGENA xmm0_xmm1 ",0x1B \n\tcall 1b \n\t"
AESKEYGENA xmm0_xmm1 ",0x36 \n\tcall 1b \n\t"
:
: "r" (rk), "r" (key)
: "memory", "cc", "0" );
}
/*
* Key expansion, 192-bit case
*/
static void aesni_setkey_enc_192( unsigned char *rk,
const unsigned char *key )
{
asm( "movdqu (%1), %%xmm0 \n\t" // copy original round key
"movdqu %%xmm0, (%0) \n\t"
"add $16, %0 \n\t"
"movq 16(%1), %%xmm1 \n\t"
"movq %%xmm1, (%0) \n\t"
"add $8, %0 \n\t"
"jmp 2f \n\t" // skip auxiliary routine
/*
* Finish generating the next 6 quarter-keys.
*
* On entry xmm0 is r3:r2:r1:r0, xmm1 is stuff:stuff:r5:r4
* and xmm2 is stuff:stuff:X:stuff with X = rot( sub( r3 ) ) ^ RCON.
*
* On exit, xmm0 is r9:r8:r7:r6 and xmm1 is stuff:stuff:r11:r10
* and those are written to the round key buffer.
*/
"1: \n\t"
"pshufd $0x55, %%xmm2, %%xmm2 \n\t" // X:X:X:X
"pxor %%xmm0, %%xmm2 \n\t" // X+r3:X+r2:X+r1:r4
"pslldq $4, %%xmm0 \n\t" // etc
"pxor %%xmm0, %%xmm2 \n\t"
"pslldq $4, %%xmm0 \n\t"
"pxor %%xmm0, %%xmm2 \n\t"
"pslldq $4, %%xmm0 \n\t"
"pxor %%xmm2, %%xmm0 \n\t" // update xmm0 = r9:r8:r7:r6
"movdqu %%xmm0, (%0) \n\t"
"add $16, %0 \n\t"
"pshufd $0xff, %%xmm0, %%xmm2 \n\t" // r9:r9:r9:r9
"pxor %%xmm1, %%xmm2 \n\t" // stuff:stuff:r9+r5:r10
"pslldq $4, %%xmm1 \n\t" // r2:r1:r0:0
"pxor %%xmm2, %%xmm1 \n\t" // xmm1 = stuff:stuff:r11:r10
"movq %%xmm1, (%0) \n\t"
"add $8, %0 \n\t"
"ret \n\t"
"2: \n\t"
AESKEYGENA xmm1_xmm2 ",0x01 \n\tcall 1b \n\t"
AESKEYGENA xmm1_xmm2 ",0x02 \n\tcall 1b \n\t"
AESKEYGENA xmm1_xmm2 ",0x04 \n\tcall 1b \n\t"
AESKEYGENA xmm1_xmm2 ",0x08 \n\tcall 1b \n\t"
AESKEYGENA xmm1_xmm2 ",0x10 \n\tcall 1b \n\t"
AESKEYGENA xmm1_xmm2 ",0x20 \n\tcall 1b \n\t"
AESKEYGENA xmm1_xmm2 ",0x40 \n\tcall 1b \n\t"
AESKEYGENA xmm1_xmm2 ",0x80 \n\tcall 1b \n\t"
:
: "r" (rk), "r" (key)
: "memory", "cc", "0" );
}
/*
* Key expansion, 256-bit case
*/
static void aesni_setkey_enc_256( unsigned char *rk,
const unsigned char *key )
{
asm( "movdqu (%1), %%xmm0 \n\t"
"movdqu %%xmm0, (%0) \n\t"
"add $16, %0 \n\t"
"movdqu 16(%1), %%xmm1 \n\t"
"movdqu %%xmm1, (%0) \n\t"
"jmp 2f \n\t" // skip auxiliary routine
/*
* Finish generating the next two round keys.
*
* On entry xmm0 is r3:r2:r1:r0, xmm1 is r7:r6:r5:r4 and
* xmm2 is X:stuff:stuff:stuff with X = rot( sub( r7 )) ^ RCON
*
* On exit, xmm0 is r11:r10:r9:r8 and xmm1 is r15:r14:r13:r12
* and those have been written to the output buffer.
*/
"1: \n\t"
"pshufd $0xff, %%xmm2, %%xmm2 \n\t"
"pxor %%xmm0, %%xmm2 \n\t"
"pslldq $4, %%xmm0 \n\t"
"pxor %%xmm0, %%xmm2 \n\t"
"pslldq $4, %%xmm0 \n\t"
"pxor %%xmm0, %%xmm2 \n\t"
"pslldq $4, %%xmm0 \n\t"
"pxor %%xmm2, %%xmm0 \n\t"
"add $16, %0 \n\t"
"movdqu %%xmm0, (%0) \n\t"
/* Set xmm2 to stuff:Y:stuff:stuff with Y = subword( r11 )
* and proceed to generate next round key from there */
AESKEYGENA xmm0_xmm2 ",0x00 \n\t"
"pshufd $0xaa, %%xmm2, %%xmm2 \n\t"
"pxor %%xmm1, %%xmm2 \n\t"
"pslldq $4, %%xmm1 \n\t"
"pxor %%xmm1, %%xmm2 \n\t"
"pslldq $4, %%xmm1 \n\t"
"pxor %%xmm1, %%xmm2 \n\t"
"pslldq $4, %%xmm1 \n\t"
"pxor %%xmm2, %%xmm1 \n\t"
"add $16, %0 \n\t"
"movdqu %%xmm1, (%0) \n\t"
"ret \n\t"
/*
* Main "loop" - Generating one more key than necessary,
* see definition of mbedtls_aes_context.buf
*/
"2: \n\t"
AESKEYGENA xmm1_xmm2 ",0x01 \n\tcall 1b \n\t"
AESKEYGENA xmm1_xmm2 ",0x02 \n\tcall 1b \n\t"
AESKEYGENA xmm1_xmm2 ",0x04 \n\tcall 1b \n\t"
AESKEYGENA xmm1_xmm2 ",0x08 \n\tcall 1b \n\t"
AESKEYGENA xmm1_xmm2 ",0x10 \n\tcall 1b \n\t"
AESKEYGENA xmm1_xmm2 ",0x20 \n\tcall 1b \n\t"
AESKEYGENA xmm1_xmm2 ",0x40 \n\tcall 1b \n\t"
:
: "r" (rk), "r" (key)
: "memory", "cc", "0" );
}
/*
* Key expansion, wrapper
*/
int mbedtls_aesni_setkey_enc( unsigned char *rk,
const unsigned char *key,
size_t bits )
{
switch( bits )
{
case 128: aesni_setkey_enc_128( rk, key ); break;
case 192: aesni_setkey_enc_192( rk, key ); break;
case 256: aesni_setkey_enc_256( rk, key ); break;
default : return( MBEDTLS_ERR_AES_INVALID_KEY_LENGTH );
}
return( 0 );
}
#endif /* MBEDTLS_HAVE_X86_64 */
#endif /* MBEDTLS_AESNI_C */
