aesni.c

00001 /*
00002  *  AES-NI support functions
00003  *
00004  *  Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
00005  *  SPDX-License-Identifier: Apache-2.0
00006  *
00007  *  Licensed under the Apache License, Version 2.0 (the "License"); you may
00008  *  not use this file except in compliance with the License.
00009  *  You may obtain a copy of the License at
00010  *
00011  *  http://www.apache.org/licenses/LICENSE-2.0
00012  *
00013  *  Unless required by applicable law or agreed to in writing, software
00014  *  distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
00015  *  WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
00016  *  See the License for the specific language governing permissions and
00017  *  limitations under the License.
00018  *
00019  *  This file is part of mbed TLS (https://tls.mbed.org)
00020  */
00021 
00022 /*
00023  * [AES-WP] http://software.intel.com/en-us/articles/intel-advanced-encryption-standard-aes-instructions-set
00024  * [CLMUL-WP] http://software.intel.com/en-us/articles/intel-carry-less-multiplication-instruction-and-its-usage-for-computing-the-gcm-mode/
00025  */
00026 
00027 #if !defined(MBEDTLS_CONFIG_FILE)
00028 #include "mbedtls/config.h"
00029 #else
00030 #include MBEDTLS_CONFIG_FILE
00031 #endif
00032 
00033 #if defined(MBEDTLS_AESNI_C)
00034 
00035 #if defined(__has_feature)
00036 #if __has_feature(memory_sanitizer)
00037 #warning "MBEDTLS_AESNI_C is known to cause spurious error reports with some memory sanitizers as they do not understand the assembly code."
00038 #endif
00039 #endif
00040 
00041 #include "mbedtls/aesni.h"
00042 
00043 #include <string.h>
00044 
00045 #ifndef asm
00046 #define asm __asm
00047 #endif
00048 
00049 #if defined(MBEDTLS_HAVE_X86_64)
00050 
00051 /*
00052  * AES-NI support detection routine
00053  */
00054 int mbedtls_aesni_has_support( unsigned int what )
00055 {
00056     static int done = 0;
00057     static unsigned int c = 0;
00058 
00059     if( ! done )
00060     {
00061         asm( "movl  $1, %%eax   \n\t"
00062              "cpuid             \n\t"
00063              : "=c" (c)
00064              :
00065              : "eax", "ebx", "edx" );
00066         done = 1;
00067     }
00068 
00069     return( ( c & what ) != 0 );
00070 }
00071 
00072 /*
00073  * Binutils needs to be at least 2.19 to support AES-NI instructions.
00074  * Unfortunately, a lot of users have a lower version now (2014-04).
00075  * Emit bytecode directly in order to support "old" version of gas.
00076  *
00077  * Opcodes from the Intel architecture reference manual, vol. 3.
00078  * We always use registers, so we don't need prefixes for memory operands.
00079  * Operand macros are in gas order (src, dst) as opposed to Intel order
00080  * (dst, src) in order to blend better into the surrounding assembly code.
00081  */
00082 #define AESDEC      ".byte 0x66,0x0F,0x38,0xDE,"
00083 #define AESDECLAST  ".byte 0x66,0x0F,0x38,0xDF,"
00084 #define AESENC      ".byte 0x66,0x0F,0x38,0xDC,"
00085 #define AESENCLAST  ".byte 0x66,0x0F,0x38,0xDD,"
00086 #define AESIMC      ".byte 0x66,0x0F,0x38,0xDB,"
00087 #define AESKEYGENA  ".byte 0x66,0x0F,0x3A,0xDF,"
00088 #define PCLMULQDQ   ".byte 0x66,0x0F,0x3A,0x44,"
00089 
00090 #define xmm0_xmm0   "0xC0"
00091 #define xmm0_xmm1   "0xC8"
00092 #define xmm0_xmm2   "0xD0"
00093 #define xmm0_xmm3   "0xD8"
00094 #define xmm0_xmm4   "0xE0"
00095 #define xmm1_xmm0   "0xC1"
00096 #define xmm1_xmm2   "0xD1"
00097 
00098 /*
00099  * AES-NI AES-ECB block en(de)cryption
00100  */
00101 int mbedtls_aesni_crypt_ecb( mbedtls_aes_context *ctx,
00102                      int mode,
00103                      const unsigned char input[16],
00104                      unsigned char output[16] )
00105 {
00106     asm( "movdqu    (%3), %%xmm0    \n\t" // load input
00107          "movdqu    (%1), %%xmm1    \n\t" // load round key 0
00108          "pxor      %%xmm1, %%xmm0  \n\t" // round 0
00109          "add       $16, %1         \n\t" // point to next round key
00110          "subl      $1, %0          \n\t" // normal rounds = nr - 1
00111          "test      %2, %2          \n\t" // mode?
00112          "jz        2f              \n\t" // 0 = decrypt
00113 
00114          "1:                        \n\t" // encryption loop
00115          "movdqu    (%1), %%xmm1    \n\t" // load round key
00116          AESENC     xmm1_xmm0      "\n\t" // do round
00117          "add       $16, %1         \n\t" // point to next round key
00118          "subl      $1, %0          \n\t" // loop
00119          "jnz       1b              \n\t"
00120          "movdqu    (%1), %%xmm1    \n\t" // load round key
00121          AESENCLAST xmm1_xmm0      "\n\t" // last round
00122          "jmp       3f              \n\t"
00123 
00124          "2:                        \n\t" // decryption loop
00125          "movdqu    (%1), %%xmm1    \n\t"
00126          AESDEC     xmm1_xmm0      "\n\t" // do round
00127          "add       $16, %1         \n\t"
00128          "subl      $1, %0          \n\t"
00129          "jnz       2b              \n\t"
00130          "movdqu    (%1), %%xmm1    \n\t" // load round key
00131          AESDECLAST xmm1_xmm0      "\n\t" // last round
00132 
00133          "3:                        \n\t"
00134          "movdqu    %%xmm0, (%4)    \n\t" // export output
00135          :
00136          : "r" (ctx->nr ), "r" (ctx->rk ), "r" (mode), "r" (input), "r" (output)
00137          : "memory", "cc", "xmm0", "xmm1" );
00138 
00139 
00140     return( 0 );
00141 }
00142 
00143 /*
00144  * GCM multiplication: c = a times b in GF(2^128)
00145  * Based on [CLMUL-WP] algorithms 1 (with equation 27) and 5.
00146  */
00147 void mbedtls_aesni_gcm_mult( unsigned char c[16],
00148                      const unsigned char a[16],
00149                      const unsigned char b[16] )
00150 {
00151     unsigned char aa[16], bb[16], cc[16];
00152     size_t i;
00153 
00154     /* The inputs are in big-endian order, so byte-reverse them */
00155     for( i = 0; i < 16; i++ )
00156     {
00157         aa[i] = a[15 - i];
00158         bb[i] = b[15 - i];
00159     }
00160 
00161     asm( "movdqu (%0), %%xmm0               \n\t" // a1:a0
00162          "movdqu (%1), %%xmm1               \n\t" // b1:b0
00163 
00164          /*
00165           * Caryless multiplication xmm2:xmm1 = xmm0 * xmm1
00166           * using [CLMUL-WP] algorithm 1 (p. 13).
00167           */
00168          "movdqa %%xmm1, %%xmm2             \n\t" // copy of b1:b0
00169          "movdqa %%xmm1, %%xmm3             \n\t" // same
00170          "movdqa %%xmm1, %%xmm4             \n\t" // same
00171          PCLMULQDQ xmm0_xmm1 ",0x00         \n\t" // a0*b0 = c1:c0
00172          PCLMULQDQ xmm0_xmm2 ",0x11         \n\t" // a1*b1 = d1:d0
00173          PCLMULQDQ xmm0_xmm3 ",0x10         \n\t" // a0*b1 = e1:e0
00174          PCLMULQDQ xmm0_xmm4 ",0x01         \n\t" // a1*b0 = f1:f0
00175          "pxor %%xmm3, %%xmm4               \n\t" // e1+f1:e0+f0
00176          "movdqa %%xmm4, %%xmm3             \n\t" // same
00177          "psrldq $8, %%xmm4                 \n\t" // 0:e1+f1
00178          "pslldq $8, %%xmm3                 \n\t" // e0+f0:0
00179          "pxor %%xmm4, %%xmm2               \n\t" // d1:d0+e1+f1
00180          "pxor %%xmm3, %%xmm1               \n\t" // c1+e0+f1:c0
00181 
00182          /*
00183           * Now shift the result one bit to the left,
00184           * taking advantage of [CLMUL-WP] eq 27 (p. 20)
00185           */
00186          "movdqa %%xmm1, %%xmm3             \n\t" // r1:r0
00187          "movdqa %%xmm2, %%xmm4             \n\t" // r3:r2
00188          "psllq $1, %%xmm1                  \n\t" // r1<<1:r0<<1
00189          "psllq $1, %%xmm2                  \n\t" // r3<<1:r2<<1
00190          "psrlq $63, %%xmm3                 \n\t" // r1>>63:r0>>63
00191          "psrlq $63, %%xmm4                 \n\t" // r3>>63:r2>>63
00192          "movdqa %%xmm3, %%xmm5             \n\t" // r1>>63:r0>>63
00193          "pslldq $8, %%xmm3                 \n\t" // r0>>63:0
00194          "pslldq $8, %%xmm4                 \n\t" // r2>>63:0
00195          "psrldq $8, %%xmm5                 \n\t" // 0:r1>>63
00196          "por %%xmm3, %%xmm1                \n\t" // r1<<1|r0>>63:r0<<1
00197          "por %%xmm4, %%xmm2                \n\t" // r3<<1|r2>>62:r2<<1
00198          "por %%xmm5, %%xmm2                \n\t" // r3<<1|r2>>62:r2<<1|r1>>63
00199 
00200          /*
00201           * Now reduce modulo the GCM polynomial x^128 + x^7 + x^2 + x + 1
00202           * using [CLMUL-WP] algorithm 5 (p. 20).
00203           * Currently xmm2:xmm1 holds x3:x2:x1:x0 (already shifted).
00204           */
00205          /* Step 2 (1) */
00206          "movdqa %%xmm1, %%xmm3             \n\t" // x1:x0
00207          "movdqa %%xmm1, %%xmm4             \n\t" // same
00208          "movdqa %%xmm1, %%xmm5             \n\t" // same
00209          "psllq $63, %%xmm3                 \n\t" // x1<<63:x0<<63 = stuff:a
00210          "psllq $62, %%xmm4                 \n\t" // x1<<62:x0<<62 = stuff:b
00211          "psllq $57, %%xmm5                 \n\t" // x1<<57:x0<<57 = stuff:c
00212 
00213          /* Step 2 (2) */
00214          "pxor %%xmm4, %%xmm3               \n\t" // stuff:a+b
00215          "pxor %%xmm5, %%xmm3               \n\t" // stuff:a+b+c
00216          "pslldq $8, %%xmm3                 \n\t" // a+b+c:0
00217          "pxor %%xmm3, %%xmm1               \n\t" // x1+a+b+c:x0 = d:x0
00218 
00219          /* Steps 3 and 4 */
00220          "movdqa %%xmm1,%%xmm0              \n\t" // d:x0
00221          "movdqa %%xmm1,%%xmm4              \n\t" // same
00222          "movdqa %%xmm1,%%xmm5              \n\t" // same
00223          "psrlq $1, %%xmm0                  \n\t" // e1:x0>>1 = e1:e0'
00224          "psrlq $2, %%xmm4                  \n\t" // f1:x0>>2 = f1:f0'
00225          "psrlq $7, %%xmm5                  \n\t" // g1:x0>>7 = g1:g0'
00226          "pxor %%xmm4, %%xmm0               \n\t" // e1+f1:e0'+f0'
00227          "pxor %%xmm5, %%xmm0               \n\t" // e1+f1+g1:e0'+f0'+g0'
00228          // e0'+f0'+g0' is almost e0+f0+g0, ex\tcept for some missing
00229          // bits carried from d. Now get those\t bits back in.
00230          "movdqa %%xmm1,%%xmm3              \n\t" // d:x0
00231          "movdqa %%xmm1,%%xmm4              \n\t" // same
00232          "movdqa %%xmm1,%%xmm5              \n\t" // same
00233          "psllq $63, %%xmm3                 \n\t" // d<<63:stuff
00234          "psllq $62, %%xmm4                 \n\t" // d<<62:stuff
00235          "psllq $57, %%xmm5                 \n\t" // d<<57:stuff
00236          "pxor %%xmm4, %%xmm3               \n\t" // d<<63+d<<62:stuff
00237          "pxor %%xmm5, %%xmm3               \n\t" // missing bits of d:stuff
00238          "psrldq $8, %%xmm3                 \n\t" // 0:missing bits of d
00239          "pxor %%xmm3, %%xmm0               \n\t" // e1+f1+g1:e0+f0+g0
00240          "pxor %%xmm1, %%xmm0               \n\t" // h1:h0
00241          "pxor %%xmm2, %%xmm0               \n\t" // x3+h1:x2+h0
00242 
00243          "movdqu %%xmm0, (%2)               \n\t" // done
00244          :
00245          : "r" (aa), "r" (bb), "r" (cc)
00246          : "memory", "cc", "xmm0", "xmm1", "xmm2", "xmm3", "xmm4", "xmm5" );
00247 
00248     /* Now byte-reverse the outputs */
00249     for( i = 0; i < 16; i++ )
00250         c[i] = cc[15 - i];
00251 
00252     return;
00253 }
00254 
00255 /*
00256  * Compute decryption round keys from encryption round keys
00257  */
00258 void mbedtls_aesni_inverse_key( unsigned char *invkey,
00259                         const unsigned char *fwdkey, int nr )
00260 {
00261     unsigned char *ik = invkey;
00262     const unsigned char *fk = fwdkey + 16 * nr;
00263 
00264     memcpy( ik, fk, 16 );
00265 
00266     for( fk -= 16, ik += 16; fk > fwdkey; fk -= 16, ik += 16 )
00267         asm( "movdqu (%0), %%xmm0       \n\t"
00268              AESIMC  xmm0_xmm0         "\n\t"
00269              "movdqu %%xmm0, (%1)       \n\t"
00270              :
00271              : "r" (fk), "r" (ik)
00272              : "memory", "xmm0" );
00273 
00274     memcpy( ik, fk, 16 );
00275 }
00276 
00277 /*
00278  * Key expansion, 128-bit case
00279  */
00280 static void aesni_setkey_enc_128( unsigned char *rk,
00281                                   const unsigned char *key )
00282 {
00283     asm( "movdqu (%1), %%xmm0               \n\t" // copy the original key
00284          "movdqu %%xmm0, (%0)               \n\t" // as round key 0
00285          "jmp 2f                            \n\t" // skip auxiliary routine
00286 
00287          /*
00288           * Finish generating the next round key.
00289           *
00290           * On entry xmm0 is r3:r2:r1:r0 and xmm1 is X:stuff:stuff:stuff
00291           * with X = rot( sub( r3 ) ) ^ RCON.
00292           *
00293           * On exit, xmm0 is r7:r6:r5:r4
00294           * with r4 = X + r0, r5 = r4 + r1, r6 = r5 + r2, r7 = r6 + r3
00295           * and those are written to the round key buffer.
00296           */
00297          "1:                                \n\t"
00298          "pshufd $0xff, %%xmm1, %%xmm1      \n\t" // X:X:X:X
00299          "pxor %%xmm0, %%xmm1               \n\t" // X+r3:X+r2:X+r1:r4
00300          "pslldq $4, %%xmm0                 \n\t" // r2:r1:r0:0
00301          "pxor %%xmm0, %%xmm1               \n\t" // X+r3+r2:X+r2+r1:r5:r4
00302          "pslldq $4, %%xmm0                 \n\t" // etc
00303          "pxor %%xmm0, %%xmm1               \n\t"
00304          "pslldq $4, %%xmm0                 \n\t"
00305          "pxor %%xmm1, %%xmm0               \n\t" // update xmm0 for next time!
00306          "add $16, %0                       \n\t" // point to next round key
00307          "movdqu %%xmm0, (%0)               \n\t" // write it
00308          "ret                               \n\t"
00309 
00310          /* Main "loop" */
00311          "2:                                \n\t"
00312          AESKEYGENA xmm0_xmm1 ",0x01        \n\tcall 1b \n\t"
00313          AESKEYGENA xmm0_xmm1 ",0x02        \n\tcall 1b \n\t"
00314          AESKEYGENA xmm0_xmm1 ",0x04        \n\tcall 1b \n\t"
00315          AESKEYGENA xmm0_xmm1 ",0x08        \n\tcall 1b \n\t"
00316          AESKEYGENA xmm0_xmm1 ",0x10        \n\tcall 1b \n\t"
00317          AESKEYGENA xmm0_xmm1 ",0x20        \n\tcall 1b \n\t"
00318          AESKEYGENA xmm0_xmm1 ",0x40        \n\tcall 1b \n\t"
00319          AESKEYGENA xmm0_xmm1 ",0x80        \n\tcall 1b \n\t"
00320          AESKEYGENA xmm0_xmm1 ",0x1B        \n\tcall 1b \n\t"
00321          AESKEYGENA xmm0_xmm1 ",0x36        \n\tcall 1b \n\t"
00322          :
00323          : "r" (rk), "r" (key)
00324          : "memory", "cc", "0" );
00325 }
00326 
00327 /*
00328  * Key expansion, 192-bit case
00329  */
00330 static void aesni_setkey_enc_192( unsigned char *rk,
00331                                   const unsigned char *key )
00332 {
00333     asm( "movdqu (%1), %%xmm0   \n\t" // copy original round key
00334          "movdqu %%xmm0, (%0)   \n\t"
00335          "add $16, %0           \n\t"
00336          "movq 16(%1), %%xmm1   \n\t"
00337          "movq %%xmm1, (%0)     \n\t"
00338          "add $8, %0            \n\t"
00339          "jmp 2f                \n\t" // skip auxiliary routine
00340 
00341          /*
00342           * Finish generating the next 6 quarter-keys.
00343           *
00344           * On entry xmm0 is r3:r2:r1:r0, xmm1 is stuff:stuff:r5:r4
00345           * and xmm2 is stuff:stuff:X:stuff with X = rot( sub( r3 ) ) ^ RCON.
00346           *
00347           * On exit, xmm0 is r9:r8:r7:r6 and xmm1 is stuff:stuff:r11:r10
00348           * and those are written to the round key buffer.
00349           */
00350          "1:                            \n\t"
00351          "pshufd $0x55, %%xmm2, %%xmm2  \n\t" // X:X:X:X
00352          "pxor %%xmm0, %%xmm2           \n\t" // X+r3:X+r2:X+r1:r4
00353          "pslldq $4, %%xmm0             \n\t" // etc
00354          "pxor %%xmm0, %%xmm2           \n\t"
00355          "pslldq $4, %%xmm0             \n\t"
00356          "pxor %%xmm0, %%xmm2           \n\t"
00357          "pslldq $4, %%xmm0             \n\t"
00358          "pxor %%xmm2, %%xmm0           \n\t" // update xmm0 = r9:r8:r7:r6
00359          "movdqu %%xmm0, (%0)           \n\t"
00360          "add $16, %0                   \n\t"
00361          "pshufd $0xff, %%xmm0, %%xmm2  \n\t" // r9:r9:r9:r9
00362          "pxor %%xmm1, %%xmm2           \n\t" // stuff:stuff:r9+r5:r10
00363          "pslldq $4, %%xmm1             \n\t" // r2:r1:r0:0
00364          "pxor %%xmm2, %%xmm1           \n\t" // xmm1 = stuff:stuff:r11:r10
00365          "movq %%xmm1, (%0)             \n\t"
00366          "add $8, %0                    \n\t"
00367          "ret                           \n\t"
00368 
00369          "2:                            \n\t"
00370          AESKEYGENA xmm1_xmm2 ",0x01    \n\tcall 1b \n\t"
00371          AESKEYGENA xmm1_xmm2 ",0x02    \n\tcall 1b \n\t"
00372          AESKEYGENA xmm1_xmm2 ",0x04    \n\tcall 1b \n\t"
00373          AESKEYGENA xmm1_xmm2 ",0x08    \n\tcall 1b \n\t"
00374          AESKEYGENA xmm1_xmm2 ",0x10    \n\tcall 1b \n\t"
00375          AESKEYGENA xmm1_xmm2 ",0x20    \n\tcall 1b \n\t"
00376          AESKEYGENA xmm1_xmm2 ",0x40    \n\tcall 1b \n\t"
00377          AESKEYGENA xmm1_xmm2 ",0x80    \n\tcall 1b \n\t"
00378 
00379          :
00380          : "r" (rk), "r" (key)
00381          : "memory", "cc", "0" );
00382 }
00383 
00384 /*
00385  * Key expansion, 256-bit case
00386  */
00387 static void aesni_setkey_enc_256( unsigned char *rk,
00388                                   const unsigned char *key )
00389 {
00390     asm( "movdqu (%1), %%xmm0           \n\t"
00391          "movdqu %%xmm0, (%0)           \n\t"
00392          "add $16, %0                   \n\t"
00393          "movdqu 16(%1), %%xmm1         \n\t"
00394          "movdqu %%xmm1, (%0)           \n\t"
00395          "jmp 2f                        \n\t" // skip auxiliary routine
00396 
00397          /*
00398           * Finish generating the next two round keys.
00399           *
00400           * On entry xmm0 is r3:r2:r1:r0, xmm1 is r7:r6:r5:r4 and
00401           * xmm2 is X:stuff:stuff:stuff with X = rot( sub( r7 )) ^ RCON
00402           *
00403           * On exit, xmm0 is r11:r10:r9:r8 and xmm1 is r15:r14:r13:r12
00404           * and those have been written to the output buffer.
00405           */
00406          "1:                                \n\t"
00407          "pshufd $0xff, %%xmm2, %%xmm2      \n\t"
00408          "pxor %%xmm0, %%xmm2               \n\t"
00409          "pslldq $4, %%xmm0                 \n\t"
00410          "pxor %%xmm0, %%xmm2               \n\t"
00411          "pslldq $4, %%xmm0                 \n\t"
00412          "pxor %%xmm0, %%xmm2               \n\t"
00413          "pslldq $4, %%xmm0                 \n\t"
00414          "pxor %%xmm2, %%xmm0               \n\t"
00415          "add $16, %0                       \n\t"
00416          "movdqu %%xmm0, (%0)               \n\t"
00417 
00418          /* Set xmm2 to stuff:Y:stuff:stuff with Y = subword( r11 )
00419           * and proceed to generate next round key from there */
00420          AESKEYGENA xmm0_xmm2 ",0x00        \n\t"
00421          "pshufd $0xaa, %%xmm2, %%xmm2      \n\t"
00422          "pxor %%xmm1, %%xmm2               \n\t"
00423          "pslldq $4, %%xmm1                 \n\t"
00424          "pxor %%xmm1, %%xmm2               \n\t"
00425          "pslldq $4, %%xmm1                 \n\t"
00426          "pxor %%xmm1, %%xmm2               \n\t"
00427          "pslldq $4, %%xmm1                 \n\t"
00428          "pxor %%xmm2, %%xmm1               \n\t"
00429          "add $16, %0                       \n\t"
00430          "movdqu %%xmm1, (%0)               \n\t"
00431          "ret                               \n\t"
00432 
00433          /*
00434           * Main "loop" - Generating one more key than necessary,
00435           * see definition of mbedtls_aes_context.buf
00436           */
00437          "2:                                \n\t"
00438          AESKEYGENA xmm1_xmm2 ",0x01        \n\tcall 1b \n\t"
00439          AESKEYGENA xmm1_xmm2 ",0x02        \n\tcall 1b \n\t"
00440          AESKEYGENA xmm1_xmm2 ",0x04        \n\tcall 1b \n\t"
00441          AESKEYGENA xmm1_xmm2 ",0x08        \n\tcall 1b \n\t"
00442          AESKEYGENA xmm1_xmm2 ",0x10        \n\tcall 1b \n\t"
00443          AESKEYGENA xmm1_xmm2 ",0x20        \n\tcall 1b \n\t"
00444          AESKEYGENA xmm1_xmm2 ",0x40        \n\tcall 1b \n\t"
00445          :
00446          : "r" (rk), "r" (key)
00447          : "memory", "cc", "0" );
00448 }
00449 
00450 /*
00451  * Key expansion, wrapper
00452  */
00453 int mbedtls_aesni_setkey_enc( unsigned char *rk,
00454                       const unsigned char *key,
00455                       size_t bits )
00456 {
00457     switch( bits )
00458     {
00459         case 128: aesni_setkey_enc_128( rk, key ); break;
00460         case 192: aesni_setkey_enc_192( rk, key ); break;
00461         case 256: aesni_setkey_enc_256( rk, key ); break;
00462         default : return( MBEDTLS_ERR_AES_INVALID_KEY_LENGTH );
00463     }
00464 
00465     return( 0 );
00466 }
00467 
00468 #endif /* MBEDTLS_HAVE_X86_64 */
00469 
00470 #endif /* MBEDTLS_AESNI_C */