go-sqlcipher/aesni.c

332 lines
12 KiB
C

/*
* AES-NI support functions
*
* Copyright The Mbed TLS Contributors
* 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.
*/
/*
* [AES-WP] https://www.intel.com/content/www/us/en/developer/articles/tool/intel-advanced-encryption-standard-aes-instructions-set.html
* [CLMUL-WP] https://www.intel.com/content/www/us/en/develop/download/intel-carry-less-multiplication-instruction-and-its-usage-for-computing-the-gcm-mode.html
*/
#include "aesni.h"
#if defined(MBEDTLS_AESNI_C)
#include <string.h>
#if defined(MBEDTLS_AESNI_HAVE_CODE)
/*
* AES-NI support detection routine
*/
int mbedtls_aesni_has_support(unsigned int what)
{
static int done = 0;
static unsigned int c = 0;
if (!done) {
/* AESNI using asm */
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(regs) ".byte 0x66,0x0F,0x38,0xDE," regs "\n\t"
#define AESDECLAST(regs) ".byte 0x66,0x0F,0x38,0xDF," regs "\n\t"
#define AESENC(regs) ".byte 0x66,0x0F,0x38,0xDC," regs "\n\t"
#define AESENCLAST(regs) ".byte 0x66,0x0F,0x38,0xDD," regs "\n\t"
#define AESIMC(regs) ".byte 0x66,0x0F,0x38,0xDB," regs "\n\t"
#define AESKEYGENA(regs, imm) ".byte 0x66,0x0F,0x3A,0xDF," regs "," imm "\n\t"
#define PCLMULQDQ(regs, imm) ".byte 0x66,0x0F,0x3A,0x44," regs "," imm "\n\t"
#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) // 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) // last round
"jmp 3f \n\t"
"2: \n\t" // decryption loop
"movdqu (%1), %%xmm1 \n\t"
AESDEC(xmm1_xmm0) // 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) // last round
"3: \n\t"
"movdqu %%xmm0, (%4) \n\t" // export output
:
: "r" (ctx->nr), "r" (ctx->buf + ctx->rk_offset), "r" (mode), "r" (input), "r" (output)
: "memory", "cc", "xmm0", "xmm1");
return 0;
}
/*
* 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)
"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") "call 1b \n\t"
AESKEYGENA(xmm0_xmm1, "0x02") "call 1b \n\t"
AESKEYGENA(xmm0_xmm1, "0x04") "call 1b \n\t"
AESKEYGENA(xmm0_xmm1, "0x08") "call 1b \n\t"
AESKEYGENA(xmm0_xmm1, "0x10") "call 1b \n\t"
AESKEYGENA(xmm0_xmm1, "0x20") "call 1b \n\t"
AESKEYGENA(xmm0_xmm1, "0x40") "call 1b \n\t"
AESKEYGENA(xmm0_xmm1, "0x80") "call 1b \n\t"
AESKEYGENA(xmm0_xmm1, "0x1B") "call 1b \n\t"
AESKEYGENA(xmm0_xmm1, "0x36") "call 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") "call 1b \n\t"
AESKEYGENA(xmm1_xmm2, "0x02") "call 1b \n\t"
AESKEYGENA(xmm1_xmm2, "0x04") "call 1b \n\t"
AESKEYGENA(xmm1_xmm2, "0x08") "call 1b \n\t"
AESKEYGENA(xmm1_xmm2, "0x10") "call 1b \n\t"
AESKEYGENA(xmm1_xmm2, "0x20") "call 1b \n\t"
AESKEYGENA(xmm1_xmm2, "0x40") "call 1b \n\t"
AESKEYGENA(xmm1_xmm2, "0x80") "call 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")
"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") "call 1b \n\t"
AESKEYGENA(xmm1_xmm2, "0x02") "call 1b \n\t"
AESKEYGENA(xmm1_xmm2, "0x04") "call 1b \n\t"
AESKEYGENA(xmm1_xmm2, "0x08") "call 1b \n\t"
AESKEYGENA(xmm1_xmm2, "0x10") "call 1b \n\t"
AESKEYGENA(xmm1_xmm2, "0x20") "call 1b \n\t"
AESKEYGENA(xmm1_xmm2, "0x40") "call 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_AESNI_HAVE_CODE */
#endif /* MBEDTLS_AESNI_C */