1 /*
2 * AES-NI support functions
3 *
4 * Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
5 * SPDX-License-Identifier: Apache-2.0
6 *
7 * Licensed under the Apache License, Version 2.0 (the "License"); you may
8 * not use this file except in compliance with the License.
9 * You may obtain a copy of the License at
10 *
11 * http://www.apache.org/licenses/LICENSE-2.0
12 *
13 * Unless required by applicable law or agreed to in writing, software
14 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
15 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
16 * See the License for the specific language governing permissions and
17 * limitations under the License.
18 *
19 * This file is part of mbed TLS (https://tls.mbed.org)
20 */
21
22 /*
23 * [AES-WP] http://software.intel.com/en-us/articles/intel-advanced-encryption-standard-aes-instructions-set
24 * [CLMUL-WP] http://software.intel.com/en-us/articles/intel-carry-less-multiplication-instruction-and-its-usage-for-computing-the-gcm-mode/
25 */
26
27 #if !defined(MBEDTLS_CONFIG_FILE)
28 #include "mbedtls/config.h"
29 #else
30 #include MBEDTLS_CONFIG_FILE
31 #endif
32
33 #if defined(MBEDTLS_AESNI_C)
34
35 #if defined(__has_feature)
36 #if __has_feature(memory_sanitizer)
37 #warning "MBEDTLS_AESNI_C is known to cause spurious error reports with some memory sanitizers as they do not understand the assembly code."
38 #endif
39 #endif
40
41 #include "mbedtls/aesni.h"
42
43 #include <string.h>
44
45 #ifndef asm
46 #define asm __asm
47 #endif
48
49 #if defined(MBEDTLS_HAVE_X86_64)
50
51 /*
52 * AES-NI support detection routine
53 */
mbedtls_aesni_has_support(unsigned int what)54 int mbedtls_aesni_has_support( unsigned int what )
55 {
56 static int done = 0;
57 static unsigned int c = 0;
58
59 if( ! done )
60 {
61 asm( "movl $1, %%eax \n\t"
62 "cpuid \n\t"
63 : "=c" (c)
64 :
65 : "eax", "ebx", "edx" );
66 done = 1;
67 }
68
69 return( ( c & what ) != 0 );
70 }
71
72 /*
73 * Binutils needs to be at least 2.19 to support AES-NI instructions.
74 * Unfortunately, a lot of users have a lower version now (2014-04).
75 * Emit bytecode directly in order to support "old" version of gas.
76 *
77 * Opcodes from the Intel architecture reference manual, vol. 3.
78 * We always use registers, so we don't need prefixes for memory operands.
79 * Operand macros are in gas order (src, dst) as opposed to Intel order
80 * (dst, src) in order to blend better into the surrounding assembly code.
81 */
82 #define AESDEC ".byte 0x66,0x0F,0x38,0xDE,"
83 #define AESDECLAST ".byte 0x66,0x0F,0x38,0xDF,"
84 #define AESENC ".byte 0x66,0x0F,0x38,0xDC,"
85 #define AESENCLAST ".byte 0x66,0x0F,0x38,0xDD,"
86 #define AESIMC ".byte 0x66,0x0F,0x38,0xDB,"
87 #define AESKEYGENA ".byte 0x66,0x0F,0x3A,0xDF,"
88 #define PCLMULQDQ ".byte 0x66,0x0F,0x3A,0x44,"
89
90 #define xmm0_xmm0 "0xC0"
91 #define xmm0_xmm1 "0xC8"
92 #define xmm0_xmm2 "0xD0"
93 #define xmm0_xmm3 "0xD8"
94 #define xmm0_xmm4 "0xE0"
95 #define xmm1_xmm0 "0xC1"
96 #define xmm1_xmm2 "0xD1"
97
98 /*
99 * AES-NI AES-ECB block en(de)cryption
100 */
mbedtls_aesni_crypt_ecb(mbedtls_aes_context * ctx,int mode,const unsigned char input[16],unsigned char output[16])101 int mbedtls_aesni_crypt_ecb( mbedtls_aes_context *ctx,
102 int mode,
103 const unsigned char input[16],
104 unsigned char output[16] )
105 {
106 asm( "movdqu (%3), %%xmm0 \n\t" // load input
107 "movdqu (%1), %%xmm1 \n\t" // load round key 0
108 "pxor %%xmm1, %%xmm0 \n\t" // round 0
109 "add $16, %1 \n\t" // point to next round key
110 "subl $1, %0 \n\t" // normal rounds = nr - 1
111 "test %2, %2 \n\t" // mode?
112 "jz 2f \n\t" // 0 = decrypt
113
114 "1: \n\t" // encryption loop
115 "movdqu (%1), %%xmm1 \n\t" // load round key
116 AESENC xmm1_xmm0 "\n\t" // do round
117 "add $16, %1 \n\t" // point to next round key
118 "subl $1, %0 \n\t" // loop
119 "jnz 1b \n\t"
120 "movdqu (%1), %%xmm1 \n\t" // load round key
121 AESENCLAST xmm1_xmm0 "\n\t" // last round
122 "jmp 3f \n\t"
123
124 "2: \n\t" // decryption loop
125 "movdqu (%1), %%xmm1 \n\t"
126 AESDEC xmm1_xmm0 "\n\t" // do round
127 "add $16, %1 \n\t"
128 "subl $1, %0 \n\t"
129 "jnz 2b \n\t"
130 "movdqu (%1), %%xmm1 \n\t" // load round key
131 AESDECLAST xmm1_xmm0 "\n\t" // last round
132
133 "3: \n\t"
134 "movdqu %%xmm0, (%4) \n\t" // export output
135 :
136 : "r" (ctx->nr), "r" (ctx->rk), "r" (mode), "r" (input), "r" (output)
137 : "memory", "cc", "xmm0", "xmm1" );
138
139
140 return( 0 );
141 }
142
143 /*
144 * GCM multiplication: c = a times b in GF(2^128)
145 * Based on [CLMUL-WP] algorithms 1 (with equation 27) and 5.
146 */
mbedtls_aesni_gcm_mult(unsigned char c[16],const unsigned char a[16],const unsigned char b[16])147 void mbedtls_aesni_gcm_mult( unsigned char c[16],
148 const unsigned char a[16],
149 const unsigned char b[16] )
150 {
151 unsigned char aa[16], bb[16], cc[16];
152 size_t i;
153
154 /* The inputs are in big-endian order, so byte-reverse them */
155 for( i = 0; i < 16; i++ )
156 {
157 aa[i] = a[15 - i];
158 bb[i] = b[15 - i];
159 }
160
161 asm( "movdqu (%0), %%xmm0 \n\t" // a1:a0
162 "movdqu (%1), %%xmm1 \n\t" // b1:b0
163
164 /*
165 * Caryless multiplication xmm2:xmm1 = xmm0 * xmm1
166 * using [CLMUL-WP] algorithm 1 (p. 13).
167 */
168 "movdqa %%xmm1, %%xmm2 \n\t" // copy of b1:b0
169 "movdqa %%xmm1, %%xmm3 \n\t" // same
170 "movdqa %%xmm1, %%xmm4 \n\t" // same
171 PCLMULQDQ xmm0_xmm1 ",0x00 \n\t" // a0*b0 = c1:c0
172 PCLMULQDQ xmm0_xmm2 ",0x11 \n\t" // a1*b1 = d1:d0
173 PCLMULQDQ xmm0_xmm3 ",0x10 \n\t" // a0*b1 = e1:e0
174 PCLMULQDQ xmm0_xmm4 ",0x01 \n\t" // a1*b0 = f1:f0
175 "pxor %%xmm3, %%xmm4 \n\t" // e1+f1:e0+f0
176 "movdqa %%xmm4, %%xmm3 \n\t" // same
177 "psrldq $8, %%xmm4 \n\t" // 0:e1+f1
178 "pslldq $8, %%xmm3 \n\t" // e0+f0:0
179 "pxor %%xmm4, %%xmm2 \n\t" // d1:d0+e1+f1
180 "pxor %%xmm3, %%xmm1 \n\t" // c1+e0+f1:c0
181
182 /*
183 * Now shift the result one bit to the left,
184 * taking advantage of [CLMUL-WP] eq 27 (p. 20)
185 */
186 "movdqa %%xmm1, %%xmm3 \n\t" // r1:r0
187 "movdqa %%xmm2, %%xmm4 \n\t" // r3:r2
188 "psllq $1, %%xmm1 \n\t" // r1<<1:r0<<1
189 "psllq $1, %%xmm2 \n\t" // r3<<1:r2<<1
190 "psrlq $63, %%xmm3 \n\t" // r1>>63:r0>>63
191 "psrlq $63, %%xmm4 \n\t" // r3>>63:r2>>63
192 "movdqa %%xmm3, %%xmm5 \n\t" // r1>>63:r0>>63
193 "pslldq $8, %%xmm3 \n\t" // r0>>63:0
194 "pslldq $8, %%xmm4 \n\t" // r2>>63:0
195 "psrldq $8, %%xmm5 \n\t" // 0:r1>>63
196 "por %%xmm3, %%xmm1 \n\t" // r1<<1|r0>>63:r0<<1
197 "por %%xmm4, %%xmm2 \n\t" // r3<<1|r2>>62:r2<<1
198 "por %%xmm5, %%xmm2 \n\t" // r3<<1|r2>>62:r2<<1|r1>>63
199
200 /*
201 * Now reduce modulo the GCM polynomial x^128 + x^7 + x^2 + x + 1
202 * using [CLMUL-WP] algorithm 5 (p. 20).
203 * Currently xmm2:xmm1 holds x3:x2:x1:x0 (already shifted).
204 */
205 /* Step 2 (1) */
206 "movdqa %%xmm1, %%xmm3 \n\t" // x1:x0
207 "movdqa %%xmm1, %%xmm4 \n\t" // same
208 "movdqa %%xmm1, %%xmm5 \n\t" // same
209 "psllq $63, %%xmm3 \n\t" // x1<<63:x0<<63 = stuff:a
210 "psllq $62, %%xmm4 \n\t" // x1<<62:x0<<62 = stuff:b
211 "psllq $57, %%xmm5 \n\t" // x1<<57:x0<<57 = stuff:c
212
213 /* Step 2 (2) */
214 "pxor %%xmm4, %%xmm3 \n\t" // stuff:a+b
215 "pxor %%xmm5, %%xmm3 \n\t" // stuff:a+b+c
216 "pslldq $8, %%xmm3 \n\t" // a+b+c:0
217 "pxor %%xmm3, %%xmm1 \n\t" // x1+a+b+c:x0 = d:x0
218
219 /* Steps 3 and 4 */
220 "movdqa %%xmm1,%%xmm0 \n\t" // d:x0
221 "movdqa %%xmm1,%%xmm4 \n\t" // same
222 "movdqa %%xmm1,%%xmm5 \n\t" // same
223 "psrlq $1, %%xmm0 \n\t" // e1:x0>>1 = e1:e0'
224 "psrlq $2, %%xmm4 \n\t" // f1:x0>>2 = f1:f0'
225 "psrlq $7, %%xmm5 \n\t" // g1:x0>>7 = g1:g0'
226 "pxor %%xmm4, %%xmm0 \n\t" // e1+f1:e0'+f0'
227 "pxor %%xmm5, %%xmm0 \n\t" // e1+f1+g1:e0'+f0'+g0'
228 // e0'+f0'+g0' is almost e0+f0+g0, ex\tcept for some missing
229 // bits carried from d. Now get those\t bits back in.
230 "movdqa %%xmm1,%%xmm3 \n\t" // d:x0
231 "movdqa %%xmm1,%%xmm4 \n\t" // same
232 "movdqa %%xmm1,%%xmm5 \n\t" // same
233 "psllq $63, %%xmm3 \n\t" // d<<63:stuff
234 "psllq $62, %%xmm4 \n\t" // d<<62:stuff
235 "psllq $57, %%xmm5 \n\t" // d<<57:stuff
236 "pxor %%xmm4, %%xmm3 \n\t" // d<<63+d<<62:stuff
237 "pxor %%xmm5, %%xmm3 \n\t" // missing bits of d:stuff
238 "psrldq $8, %%xmm3 \n\t" // 0:missing bits of d
239 "pxor %%xmm3, %%xmm0 \n\t" // e1+f1+g1:e0+f0+g0
240 "pxor %%xmm1, %%xmm0 \n\t" // h1:h0
241 "pxor %%xmm2, %%xmm0 \n\t" // x3+h1:x2+h0
242
243 "movdqu %%xmm0, (%2) \n\t" // done
244 :
245 : "r" (aa), "r" (bb), "r" (cc)
246 : "memory", "cc", "xmm0", "xmm1", "xmm2", "xmm3", "xmm4", "xmm5" );
247
248 /* Now byte-reverse the outputs */
249 for( i = 0; i < 16; i++ )
250 c[i] = cc[15 - i];
251
252 return;
253 }
254
255 /*
256 * Compute decryption round keys from encryption round keys
257 */
mbedtls_aesni_inverse_key(unsigned char * invkey,const unsigned char * fwdkey,int nr)258 void mbedtls_aesni_inverse_key( unsigned char *invkey,
259 const unsigned char *fwdkey, int nr )
260 {
261 unsigned char *ik = invkey;
262 const unsigned char *fk = fwdkey + 16 * nr;
263
264 memcpy( ik, fk, 16 );
265
266 for( fk -= 16, ik += 16; fk > fwdkey; fk -= 16, ik += 16 )
267 asm( "movdqu (%0), %%xmm0 \n\t"
268 AESIMC xmm0_xmm0 "\n\t"
269 "movdqu %%xmm0, (%1) \n\t"
270 :
271 : "r" (fk), "r" (ik)
272 : "memory", "xmm0" );
273
274 memcpy( ik, fk, 16 );
275 }
276
277 /*
278 * Key expansion, 128-bit case
279 */
aesni_setkey_enc_128(unsigned char * rk,const unsigned char * key)280 static void aesni_setkey_enc_128( unsigned char *rk,
281 const unsigned char *key )
282 {
283 asm( "movdqu (%1), %%xmm0 \n\t" // copy the original key
284 "movdqu %%xmm0, (%0) \n\t" // as round key 0
285 "jmp 2f \n\t" // skip auxiliary routine
286
287 /*
288 * Finish generating the next round key.
289 *
290 * On entry xmm0 is r3:r2:r1:r0 and xmm1 is X:stuff:stuff:stuff
291 * with X = rot( sub( r3 ) ) ^ RCON.
292 *
293 * On exit, xmm0 is r7:r6:r5:r4
294 * with r4 = X + r0, r5 = r4 + r1, r6 = r5 + r2, r7 = r6 + r3
295 * and those are written to the round key buffer.
296 */
297 "1: \n\t"
298 "pshufd $0xff, %%xmm1, %%xmm1 \n\t" // X:X:X:X
299 "pxor %%xmm0, %%xmm1 \n\t" // X+r3:X+r2:X+r1:r4
300 "pslldq $4, %%xmm0 \n\t" // r2:r1:r0:0
301 "pxor %%xmm0, %%xmm1 \n\t" // X+r3+r2:X+r2+r1:r5:r4
302 "pslldq $4, %%xmm0 \n\t" // etc
303 "pxor %%xmm0, %%xmm1 \n\t"
304 "pslldq $4, %%xmm0 \n\t"
305 "pxor %%xmm1, %%xmm0 \n\t" // update xmm0 for next time!
306 "add $16, %0 \n\t" // point to next round key
307 "movdqu %%xmm0, (%0) \n\t" // write it
308 "ret \n\t"
309
310 /* Main "loop" */
311 "2: \n\t"
312 AESKEYGENA xmm0_xmm1 ",0x01 \n\tcall 1b \n\t"
313 AESKEYGENA xmm0_xmm1 ",0x02 \n\tcall 1b \n\t"
314 AESKEYGENA xmm0_xmm1 ",0x04 \n\tcall 1b \n\t"
315 AESKEYGENA xmm0_xmm1 ",0x08 \n\tcall 1b \n\t"
316 AESKEYGENA xmm0_xmm1 ",0x10 \n\tcall 1b \n\t"
317 AESKEYGENA xmm0_xmm1 ",0x20 \n\tcall 1b \n\t"
318 AESKEYGENA xmm0_xmm1 ",0x40 \n\tcall 1b \n\t"
319 AESKEYGENA xmm0_xmm1 ",0x80 \n\tcall 1b \n\t"
320 AESKEYGENA xmm0_xmm1 ",0x1B \n\tcall 1b \n\t"
321 AESKEYGENA xmm0_xmm1 ",0x36 \n\tcall 1b \n\t"
322 :
323 : "r" (rk), "r" (key)
324 : "memory", "cc", "0" );
325 }
326
327 /*
328 * Key expansion, 192-bit case
329 */
aesni_setkey_enc_192(unsigned char * rk,const unsigned char * key)330 static void aesni_setkey_enc_192( unsigned char *rk,
331 const unsigned char *key )
332 {
333 asm( "movdqu (%1), %%xmm0 \n\t" // copy original round key
334 "movdqu %%xmm0, (%0) \n\t"
335 "add $16, %0 \n\t"
336 "movq 16(%1), %%xmm1 \n\t"
337 "movq %%xmm1, (%0) \n\t"
338 "add $8, %0 \n\t"
339 "jmp 2f \n\t" // skip auxiliary routine
340
341 /*
342 * Finish generating the next 6 quarter-keys.
343 *
344 * On entry xmm0 is r3:r2:r1:r0, xmm1 is stuff:stuff:r5:r4
345 * and xmm2 is stuff:stuff:X:stuff with X = rot( sub( r3 ) ) ^ RCON.
346 *
347 * On exit, xmm0 is r9:r8:r7:r6 and xmm1 is stuff:stuff:r11:r10
348 * and those are written to the round key buffer.
349 */
350 "1: \n\t"
351 "pshufd $0x55, %%xmm2, %%xmm2 \n\t" // X:X:X:X
352 "pxor %%xmm0, %%xmm2 \n\t" // X+r3:X+r2:X+r1:r4
353 "pslldq $4, %%xmm0 \n\t" // etc
354 "pxor %%xmm0, %%xmm2 \n\t"
355 "pslldq $4, %%xmm0 \n\t"
356 "pxor %%xmm0, %%xmm2 \n\t"
357 "pslldq $4, %%xmm0 \n\t"
358 "pxor %%xmm2, %%xmm0 \n\t" // update xmm0 = r9:r8:r7:r6
359 "movdqu %%xmm0, (%0) \n\t"
360 "add $16, %0 \n\t"
361 "pshufd $0xff, %%xmm0, %%xmm2 \n\t" // r9:r9:r9:r9
362 "pxor %%xmm1, %%xmm2 \n\t" // stuff:stuff:r9+r5:r10
363 "pslldq $4, %%xmm1 \n\t" // r2:r1:r0:0
364 "pxor %%xmm2, %%xmm1 \n\t" // xmm1 = stuff:stuff:r11:r10
365 "movq %%xmm1, (%0) \n\t"
366 "add $8, %0 \n\t"
367 "ret \n\t"
368
369 "2: \n\t"
370 AESKEYGENA xmm1_xmm2 ",0x01 \n\tcall 1b \n\t"
371 AESKEYGENA xmm1_xmm2 ",0x02 \n\tcall 1b \n\t"
372 AESKEYGENA xmm1_xmm2 ",0x04 \n\tcall 1b \n\t"
373 AESKEYGENA xmm1_xmm2 ",0x08 \n\tcall 1b \n\t"
374 AESKEYGENA xmm1_xmm2 ",0x10 \n\tcall 1b \n\t"
375 AESKEYGENA xmm1_xmm2 ",0x20 \n\tcall 1b \n\t"
376 AESKEYGENA xmm1_xmm2 ",0x40 \n\tcall 1b \n\t"
377 AESKEYGENA xmm1_xmm2 ",0x80 \n\tcall 1b \n\t"
378
379 :
380 : "r" (rk), "r" (key)
381 : "memory", "cc", "0" );
382 }
383
384 /*
385 * Key expansion, 256-bit case
386 */
aesni_setkey_enc_256(unsigned char * rk,const unsigned char * key)387 static void aesni_setkey_enc_256( unsigned char *rk,
388 const unsigned char *key )
389 {
390 asm( "movdqu (%1), %%xmm0 \n\t"
391 "movdqu %%xmm0, (%0) \n\t"
392 "add $16, %0 \n\t"
393 "movdqu 16(%1), %%xmm1 \n\t"
394 "movdqu %%xmm1, (%0) \n\t"
395 "jmp 2f \n\t" // skip auxiliary routine
396
397 /*
398 * Finish generating the next two round keys.
399 *
400 * On entry xmm0 is r3:r2:r1:r0, xmm1 is r7:r6:r5:r4 and
401 * xmm2 is X:stuff:stuff:stuff with X = rot( sub( r7 )) ^ RCON
402 *
403 * On exit, xmm0 is r11:r10:r9:r8 and xmm1 is r15:r14:r13:r12
404 * and those have been written to the output buffer.
405 */
406 "1: \n\t"
407 "pshufd $0xff, %%xmm2, %%xmm2 \n\t"
408 "pxor %%xmm0, %%xmm2 \n\t"
409 "pslldq $4, %%xmm0 \n\t"
410 "pxor %%xmm0, %%xmm2 \n\t"
411 "pslldq $4, %%xmm0 \n\t"
412 "pxor %%xmm0, %%xmm2 \n\t"
413 "pslldq $4, %%xmm0 \n\t"
414 "pxor %%xmm2, %%xmm0 \n\t"
415 "add $16, %0 \n\t"
416 "movdqu %%xmm0, (%0) \n\t"
417
418 /* Set xmm2 to stuff:Y:stuff:stuff with Y = subword( r11 )
419 * and proceed to generate next round key from there */
420 AESKEYGENA xmm0_xmm2 ",0x00 \n\t"
421 "pshufd $0xaa, %%xmm2, %%xmm2 \n\t"
422 "pxor %%xmm1, %%xmm2 \n\t"
423 "pslldq $4, %%xmm1 \n\t"
424 "pxor %%xmm1, %%xmm2 \n\t"
425 "pslldq $4, %%xmm1 \n\t"
426 "pxor %%xmm1, %%xmm2 \n\t"
427 "pslldq $4, %%xmm1 \n\t"
428 "pxor %%xmm2, %%xmm1 \n\t"
429 "add $16, %0 \n\t"
430 "movdqu %%xmm1, (%0) \n\t"
431 "ret \n\t"
432
433 /*
434 * Main "loop" - Generating one more key than necessary,
435 * see definition of mbedtls_aes_context.buf
436 */
437 "2: \n\t"
438 AESKEYGENA xmm1_xmm2 ",0x01 \n\tcall 1b \n\t"
439 AESKEYGENA xmm1_xmm2 ",0x02 \n\tcall 1b \n\t"
440 AESKEYGENA xmm1_xmm2 ",0x04 \n\tcall 1b \n\t"
441 AESKEYGENA xmm1_xmm2 ",0x08 \n\tcall 1b \n\t"
442 AESKEYGENA xmm1_xmm2 ",0x10 \n\tcall 1b \n\t"
443 AESKEYGENA xmm1_xmm2 ",0x20 \n\tcall 1b \n\t"
444 AESKEYGENA xmm1_xmm2 ",0x40 \n\tcall 1b \n\t"
445 :
446 : "r" (rk), "r" (key)
447 : "memory", "cc", "0" );
448 }
449
450 /*
451 * Key expansion, wrapper
452 */
mbedtls_aesni_setkey_enc(unsigned char * rk,const unsigned char * key,size_t bits)453 int mbedtls_aesni_setkey_enc( unsigned char *rk,
454 const unsigned char *key,
455 size_t bits )
456 {
457 switch( bits )
458 {
459 case 128: aesni_setkey_enc_128( rk, key ); break;
460 case 192: aesni_setkey_enc_192( rk, key ); break;
461 case 256: aesni_setkey_enc_256( rk, key ); break;
462 default : return( MBEDTLS_ERR_AES_INVALID_KEY_LENGTH );
463 }
464
465 return( 0 );
466 }
467
468 #endif /* MBEDTLS_HAVE_X86_64 */
469
470 #endif /* MBEDTLS_AESNI_C */
471