Hannes Tschofenig
Example program to test AES-GCM functionality. Used for a workshop
Diff: SSL/library/aesni.c
- Revision:
- 0:796d0f61a05b
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/SSL/library/aesni.c Thu Sep 27 06:34:22 2018 +0000
@@ -0,0 +1,465 @@
+/*
+ * AES-NI support functions
+ *
+ * Copyright (C) 2013, Brainspark B.V.
+ *
+ * This file is part of PolarSSL (http://www.polarssl.org)
+ * Lead Maintainer: Paul Bakker <polarssl_maintainer at polarssl.org>
+ *
+ * All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+/*
+ * [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(POLARSSL_CONFIG_FILE)
+#include "polarssl/config.h"
+#else
+#include POLARSSL_CONFIG_FILE
+#endif
+
+#if defined(POLARSSL_AESNI_C)
+
+#include "polarssl/aesni.h"
+#include <stdio.h>
+
+#if defined(POLARSSL_HAVE_X86_64)
+
+/*
+ * AES-NI support detection routine
+ */
+int aesni_supports( unsigned int what )
+{
+ static int done = 0;
+ static unsigned int c = 0;
+
+ if( ! done )
+ {
+ asm( "movl $1, %%eax \n"
+ "cpuid \n"
+ : "=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 aesni_crypt_ecb( aes_context *ctx,
+ int mode,
+ const unsigned char input[16],
+ unsigned char output[16] )
+{
+ asm( "movdqu (%3), %%xmm0 \n" // load input
+ "movdqu (%1), %%xmm1 \n" // load round key 0
+ "pxor %%xmm1, %%xmm0 \n" // round 0
+ "addq $16, %1 \n" // point to next round key
+ "subl $1, %0 \n" // normal rounds = nr - 1
+ "test %2, %2 \n" // mode?
+ "jz 2f \n" // 0 = decrypt
+
+ "1: \n" // encryption loop
+ "movdqu (%1), %%xmm1 \n" // load round key
+ AESENC xmm1_xmm0 "\n" // do round
+ "addq $16, %1 \n" // point to next round key
+ "subl $1, %0 \n" // loop
+ "jnz 1b \n"
+ "movdqu (%1), %%xmm1 \n" // load round key
+ AESENCLAST xmm1_xmm0 "\n" // last round
+ "jmp 3f \n"
+
+ "2: \n" // decryption loop
+ "movdqu (%1), %%xmm1 \n"
+ AESDEC xmm1_xmm0 "\n" // do round
+ "addq $16, %1 \n"
+ "subl $1, %0 \n"
+ "jnz 2b \n"
+ "movdqu (%1), %%xmm1 \n" // load round key
+ AESDECLAST xmm1_xmm0 "\n" // last round
+
+ "3: \n"
+ "movdqu %%xmm0, (%4) \n" // 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 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" // a1:a0
+ "movdqu (%1), %%xmm1 \n" // b1:b0
+
+ /*
+ * Caryless multiplication xmm2:xmm1 = xmm0 * xmm1
+ * using [CLMUL-WP] algorithm 1 (p. 13).
+ */
+ "movdqa %%xmm1, %%xmm2 \n" // copy of b1:b0
+ "movdqa %%xmm1, %%xmm3 \n" // same
+ "movdqa %%xmm1, %%xmm4 \n" // same
+ PCLMULQDQ xmm0_xmm1 ",0x00 \n" // a0*b0 = c1:c0
+ PCLMULQDQ xmm0_xmm2 ",0x11 \n" // a1*b1 = d1:d0
+ PCLMULQDQ xmm0_xmm3 ",0x10 \n" // a0*b1 = e1:e0
+ PCLMULQDQ xmm0_xmm4 ",0x01 \n" // a1*b0 = f1:f0
+ "pxor %%xmm3, %%xmm4 \n" // e1+f1:e0+f0
+ "movdqa %%xmm4, %%xmm3 \n" // same
+ "psrldq $8, %%xmm4 \n" // 0:e1+f1
+ "pslldq $8, %%xmm3 \n" // e0+f0:0
+ "pxor %%xmm4, %%xmm2 \n" // d1:d0+e1+f1
+ "pxor %%xmm3, %%xmm1 \n" // 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" // r1:r0
+ "movdqa %%xmm2, %%xmm4 \n" // r3:r2
+ "psllq $1, %%xmm1 \n" // r1<<1:r0<<1
+ "psllq $1, %%xmm2 \n" // r3<<1:r2<<1
+ "psrlq $63, %%xmm3 \n" // r1>>63:r0>>63
+ "psrlq $63, %%xmm4 \n" // r3>>63:r2>>63
+ "movdqa %%xmm3, %%xmm5 \n" // r1>>63:r0>>63
+ "pslldq $8, %%xmm3 \n" // r0>>63:0
+ "pslldq $8, %%xmm4 \n" // r2>>63:0
+ "psrldq $8, %%xmm5 \n" // 0:r1>>63
+ "por %%xmm3, %%xmm1 \n" // r1<<1|r0>>63:r0<<1
+ "por %%xmm4, %%xmm2 \n" // r3<<1|r2>>62:r2<<1
+ "por %%xmm5, %%xmm2 \n" // 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" // x1:x0
+ "movdqa %%xmm1, %%xmm4 \n" // same
+ "movdqa %%xmm1, %%xmm5 \n" // same
+ "psllq $63, %%xmm3 \n" // x1<<63:x0<<63 = stuff:a
+ "psllq $62, %%xmm4 \n" // x1<<62:x0<<62 = stuff:b
+ "psllq $57, %%xmm5 \n" // x1<<57:x0<<57 = stuff:c
+
+ /* Step 2 (2) */
+ "pxor %%xmm4, %%xmm3 \n" // stuff:a+b
+ "pxor %%xmm5, %%xmm3 \n" // stuff:a+b+c
+ "pslldq $8, %%xmm3 \n" // a+b+c:0
+ "pxor %%xmm3, %%xmm1 \n" // x1+a+b+c:x0 = d:x0
+
+ /* Steps 3 and 4 */
+ "movdqa %%xmm1,%%xmm0 \n" // d:x0
+ "movdqa %%xmm1,%%xmm4 \n" // same
+ "movdqa %%xmm1,%%xmm5 \n" // same
+ "psrlq $1, %%xmm0 \n" // e1:x0>>1 = e1:e0'
+ "psrlq $2, %%xmm4 \n" // f1:x0>>2 = f1:f0'
+ "psrlq $7, %%xmm5 \n" // g1:x0>>7 = g1:g0'
+ "pxor %%xmm4, %%xmm0 \n" // e1+f1:e0'+f0'
+ "pxor %%xmm5, %%xmm0 \n" // e1+f1+g1:e0'+f0'+g0'
+ // e0'+f0'+g0' is almost e0+f0+g0, except for some missing
+ // bits carried from d. Now get those bits back in.
+ "movdqa %%xmm1,%%xmm3 \n" // d:x0
+ "movdqa %%xmm1,%%xmm4 \n" // same
+ "movdqa %%xmm1,%%xmm5 \n" // same
+ "psllq $63, %%xmm3 \n" // d<<63:stuff
+ "psllq $62, %%xmm4 \n" // d<<62:stuff
+ "psllq $57, %%xmm5 \n" // d<<57:stuff
+ "pxor %%xmm4, %%xmm3 \n" // d<<63+d<<62:stuff
+ "pxor %%xmm5, %%xmm3 \n" // missing bits of d:stuff
+ "psrldq $8, %%xmm3 \n" // 0:missing bits of d
+ "pxor %%xmm3, %%xmm0 \n" // e1+f1+g1:e0+f0+g0
+ "pxor %%xmm1, %%xmm0 \n" // h1:h0
+ "pxor %%xmm2, %%xmm0 \n" // x3+h1:x2+h0
+
+ "movdqu %%xmm0, (%2) \n" // 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 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"
+ AESIMC xmm0_xmm0 "\n"
+ "movdqu %%xmm0, (%1) \n"
+ :
+ : "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" // copy the original key
+ "movdqu %%xmm0, (%0) \n" // as round key 0
+ "jmp 2f \n" // 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"
+ "pshufd $0xff, %%xmm1, %%xmm1 \n" // X:X:X:X
+ "pxor %%xmm0, %%xmm1 \n" // X+r3:X+r2:X+r1:r4
+ "pslldq $4, %%xmm0 \n" // r2:r1:r0:0
+ "pxor %%xmm0, %%xmm1 \n" // X+r3+r2:X+r2+r1:r5:r4
+ "pslldq $4, %%xmm0 \n" // etc
+ "pxor %%xmm0, %%xmm1 \n"
+ "pslldq $4, %%xmm0 \n"
+ "pxor %%xmm1, %%xmm0 \n" // update xmm0 for next time!
+ "add $16, %0 \n" // point to next round key
+ "movdqu %%xmm0, (%0) \n" // write it
+ "ret \n"
+
+ /* Main "loop" */
+ "2: \n"
+ AESKEYGENA xmm0_xmm1 ",0x01 \ncall 1b \n"
+ AESKEYGENA xmm0_xmm1 ",0x02 \ncall 1b \n"
+ AESKEYGENA xmm0_xmm1 ",0x04 \ncall 1b \n"
+ AESKEYGENA xmm0_xmm1 ",0x08 \ncall 1b \n"
+ AESKEYGENA xmm0_xmm1 ",0x10 \ncall 1b \n"
+ AESKEYGENA xmm0_xmm1 ",0x20 \ncall 1b \n"
+ AESKEYGENA xmm0_xmm1 ",0x40 \ncall 1b \n"
+ AESKEYGENA xmm0_xmm1 ",0x80 \ncall 1b \n"
+ AESKEYGENA xmm0_xmm1 ",0x1B \ncall 1b \n"
+ AESKEYGENA xmm0_xmm1 ",0x36 \ncall 1b \n"
+ :
+ : "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" // copy original round key
+ "movdqu %%xmm0, (%0) \n"
+ "add $16, %0 \n"
+ "movq 16(%1), %%xmm1 \n"
+ "movq %%xmm1, (%0) \n"
+ "add $8, %0 \n"
+ "jmp 2f \n" // 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"
+ "pshufd $0x55, %%xmm2, %%xmm2 \n" // X:X:X:X
+ "pxor %%xmm0, %%xmm2 \n" // X+r3:X+r2:X+r1:r4
+ "pslldq $4, %%xmm0 \n" // etc
+ "pxor %%xmm0, %%xmm2 \n"
+ "pslldq $4, %%xmm0 \n"
+ "pxor %%xmm0, %%xmm2 \n"
+ "pslldq $4, %%xmm0 \n"
+ "pxor %%xmm2, %%xmm0 \n" // update xmm0 = r9:r8:r7:r6
+ "movdqu %%xmm0, (%0) \n"
+ "add $16, %0 \n"
+ "pshufd $0xff, %%xmm0, %%xmm2 \n" // r9:r9:r9:r9
+ "pxor %%xmm1, %%xmm2 \n" // stuff:stuff:r9+r5:r10
+ "pslldq $4, %%xmm1 \n" // r2:r1:r0:0
+ "pxor %%xmm2, %%xmm1 \n" // update xmm1 = stuff:stuff:r11:r10
+ "movq %%xmm1, (%0) \n"
+ "add $8, %0 \n"
+ "ret \n"
+
+ "2: \n"
+ AESKEYGENA xmm1_xmm2 ",0x01 \ncall 1b \n"
+ AESKEYGENA xmm1_xmm2 ",0x02 \ncall 1b \n"
+ AESKEYGENA xmm1_xmm2 ",0x04 \ncall 1b \n"
+ AESKEYGENA xmm1_xmm2 ",0x08 \ncall 1b \n"
+ AESKEYGENA xmm1_xmm2 ",0x10 \ncall 1b \n"
+ AESKEYGENA xmm1_xmm2 ",0x20 \ncall 1b \n"
+ AESKEYGENA xmm1_xmm2 ",0x40 \ncall 1b \n"
+ AESKEYGENA xmm1_xmm2 ",0x80 \ncall 1b \n"
+
+ :
+ : "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"
+ "movdqu %%xmm0, (%0) \n"
+ "add $16, %0 \n"
+ "movdqu 16(%1), %%xmm1 \n"
+ "movdqu %%xmm1, (%0) \n"
+ "jmp 2f \n" // 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"
+ "pshufd $0xff, %%xmm2, %%xmm2 \n"
+ "pxor %%xmm0, %%xmm2 \n"
+ "pslldq $4, %%xmm0 \n"
+ "pxor %%xmm0, %%xmm2 \n"
+ "pslldq $4, %%xmm0 \n"
+ "pxor %%xmm0, %%xmm2 \n"
+ "pslldq $4, %%xmm0 \n"
+ "pxor %%xmm2, %%xmm0 \n"
+ "add $16, %0 \n"
+ "movdqu %%xmm0, (%0) \n"
+
+ /* 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"
+ "pshufd $0xaa, %%xmm2, %%xmm2 \n"
+ "pxor %%xmm1, %%xmm2 \n"
+ "pslldq $4, %%xmm1 \n"
+ "pxor %%xmm1, %%xmm2 \n"
+ "pslldq $4, %%xmm1 \n"
+ "pxor %%xmm1, %%xmm2 \n"
+ "pslldq $4, %%xmm1 \n"
+ "pxor %%xmm2, %%xmm1 \n"
+ "add $16, %0 \n"
+ "movdqu %%xmm1, (%0) \n"
+ "ret \n"
+
+ /*
+ * Main "loop" - Generating one more key than necessary,
+ * see definition of aes_context.buf
+ */
+ "2: \n"
+ AESKEYGENA xmm1_xmm2 ",0x01 \ncall 1b \n"
+ AESKEYGENA xmm1_xmm2 ",0x02 \ncall 1b \n"
+ AESKEYGENA xmm1_xmm2 ",0x04 \ncall 1b \n"
+ AESKEYGENA xmm1_xmm2 ",0x08 \ncall 1b \n"
+ AESKEYGENA xmm1_xmm2 ",0x10 \ncall 1b \n"
+ AESKEYGENA xmm1_xmm2 ",0x20 \ncall 1b \n"
+ AESKEYGENA xmm1_xmm2 ",0x40 \ncall 1b \n"
+ :
+ : "r" (rk), "r" (key)
+ : "memory", "cc", "0" );
+}
+
+/*
+ * Key expansion, wrapper
+ */
+int 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( POLARSSL_ERR_AES_INVALID_KEY_LENGTH );
+ }
+
+ return( 0 );
+}
+
+#endif /* POLARSSL_HAVE_X86_64 */
+
+#endif /* POLARSSL_AESNI_C */
+
+