crypto/armcap.c

   1 /*
   2  * Copyright 2011-2021 The OpenSSL Project Authors. All Rights Reserved.
   3  *
   4  * Licensed under the Apache License 2.0 (the "License").  You may not use
   5  * this file except in compliance with the License.  You can obtain a copy
   6  * in the file LICENSE in the source distribution or at
   7  * https://www.openssl.org/source/license.html
   8  */
   9
  10 #include <stdio.h>
  11 #include <stdlib.h>
  12 #include <string.h>
  13 #include <setjmp.h>
  14 #include <signal.h>
  15 #include <openssl/crypto.h>
  16 #ifdef __APPLE__
  17 #include <sys/sysctl.h>
  18 #endif
  19 #include "internal/cryptlib.h"
  20 #include <unistd.h>
  21
  22 #include "arm_arch.h"
  23
  24 unsigned int OPENSSL_armcap_P = 0;
  25 unsigned int OPENSSL_arm_midr = 0;
  26 unsigned int OPENSSL_armv8_rsa_neonized = 0;
  27
  28 #if __ARM_MAX_ARCH__<7
  29 void OPENSSL_cpuid_setup(void)
  30 {
  31 }
  32
  33 uint32_t OPENSSL_rdtsc(void)
  34 {
  35     return 0;
  36 }
  37 #else
  38 static sigset_t all_masked;
  39
  40 static sigjmp_buf ill_jmp;
  41 static void ill_handler(int sig)
  42 {
  43     siglongjmp(ill_jmp, sig);
  44 }
  45
  46 /*
  47  * Following subroutines could have been inlined, but it's not all
  48  * ARM compilers support inline assembler...
  49  */
  50 void _armv7_neon_probe(void);
  51 void _armv8_aes_probe(void);
  52 void _armv8_sha1_probe(void);
  53 void _armv8_sha256_probe(void);
  54 void _armv8_pmull_probe(void);
  55 # ifdef __aarch64__
  56 void _armv8_sha512_probe(void);
  57 unsigned int _armv8_cpuid_probe(void);
  58 void _armv8_rng_probe(void);
  59
  60 size_t OPENSSL_rndr_asm(unsigned char *buf, size_t len);
  61 size_t OPENSSL_rndrrs_asm(unsigned char *buf, size_t len);
  62
  63 size_t OPENSSL_rndr_bytes(unsigned char *buf, size_t len);
  64 size_t OPENSSL_rndrrs_bytes(unsigned char *buf, size_t len);
  65
  66 static size_t OPENSSL_rndr_wrapper(size_t (*func)(unsigned char *, size_t), unsigned char *buf, size_t len)
  67 {
  68     size_t buffer_size;
  69     int i;
  70
  71     for (i = 0; i < 8; i++) {
  72         buffer_size = func(buf, len);
  73         if (buffer_size == len)
  74             break;
  75         usleep(5000);  /* 5000 microseconds (5 milliseconds) */
  76     }
  77     return buffer_size;
  78 }
  79
  80 size_t OPENSSL_rndr_bytes(unsigned char *buf, size_t len)
  81 {
  82     return OPENSSL_rndr_wrapper(OPENSSL_rndr_asm, buf, len);
  83 }
  84
  85 size_t OPENSSL_rndrrs_bytes(unsigned char *buf, size_t len)
  86 {
  87     return OPENSSL_rndr_wrapper(OPENSSL_rndrrs_asm, buf, len);
  88 }
  89 # endif
  90 uint32_t _armv7_tick(void);
  91
  92 uint32_t OPENSSL_rdtsc(void)
  93 {
  94     if (OPENSSL_armcap_P & ARMV7_TICK)
  95         return _armv7_tick();
  96     else
  97         return 0;
  98 }
  99
 100 # if defined(__GNUC__) && __GNUC__>=2
 101 void OPENSSL_cpuid_setup(void) __attribute__ ((constructor));
 102 # endif
 103
 104 # if defined(__GLIBC__) && defined(__GLIBC_PREREQ)
 105 #  if __GLIBC_PREREQ(2, 16)
 106 #   include <sys/auxv.h>
 107 #   define OSSL_IMPLEMENT_GETAUXVAL
 108 #  endif
 109 # elif defined(__ANDROID_API__)
 110 /* see https://developer.android.google.cn/ndk/guides/cpu-features */
 111 #  if __ANDROID_API__ >= 18
 112 #   include <sys/auxv.h>
 113 #   define OSSL_IMPLEMENT_GETAUXVAL
 114 #  endif
 115 # endif
 116 # if defined(__FreeBSD__)
 117 #  include <sys/param.h>
 118 #  if __FreeBSD_version >= 1200000
 119 #   include <sys/auxv.h>
 120 #   define OSSL_IMPLEMENT_GETAUXVAL
 121
 122 static unsigned long getauxval(unsigned long key)
 123 {
 124   unsigned long val = 0ul;
 125
 126   if (elf_aux_info((int)key, &val, sizeof(val)) != 0)
 127     return 0ul;
 128
 129   return val;
 130 }
 131 #  endif
 132 # endif
 133
 134 /*
 135  * Android: according to https://developer.android.com/ndk/guides/cpu-features,
 136  * getauxval is supported starting with API level 18
 137  */
 138 #  if defined(__ANDROID__) && defined(__ANDROID_API__) && __ANDROID_API__ >= 18
 139 #   include <sys/auxv.h>
 140 #   define OSSL_IMPLEMENT_GETAUXVAL
 141 #  endif
 142
 143 /*
 144  * ARM puts the feature bits for Crypto Extensions in AT_HWCAP2, whereas
 145  * AArch64 used AT_HWCAP.
 146  */
 147 # ifndef AT_HWCAP
 148 #  define AT_HWCAP               16
 149 # endif
 150 # ifndef AT_HWCAP2
 151 #  define AT_HWCAP2              26
 152 # endif
 153 # if defined(__arm__) || defined (__arm)
 154 #  define HWCAP                  AT_HWCAP
 155 #  define HWCAP_NEON             (1 << 12)
 156
 157 #  define HWCAP_CE               AT_HWCAP2
 158 #  define HWCAP_CE_AES           (1 << 0)
 159 #  define HWCAP_CE_PMULL         (1 << 1)
 160 #  define HWCAP_CE_SHA1          (1 << 2)
 161 #  define HWCAP_CE_SHA256        (1 << 3)
 162 # elif defined(__aarch64__)
 163 #  define HWCAP                  AT_HWCAP
 164 #  define HWCAP_NEON             (1 << 1)
 165
 166 #  define HWCAP_CE               HWCAP
 167 #  define HWCAP_CE_AES           (1 << 3)
 168 #  define HWCAP_CE_PMULL         (1 << 4)
 169 #  define HWCAP_CE_SHA1          (1 << 5)
 170 #  define HWCAP_CE_SHA256        (1 << 6)
 171 #  define HWCAP_CPUID            (1 << 11)
 172 #  define HWCAP_CE_SHA512        (1 << 21)
 173                                   /* AT_HWCAP2 */
 174 #  define HWCAP2                 26
 175 #  define HWCAP2_RNG             (1 << 16)
 176 # endif
 177
 178 void OPENSSL_cpuid_setup(void)
 179 {
 180     const char *e;
 181     struct sigaction ill_oact, ill_act;
 182     sigset_t oset;
 183     static int trigger = 0;
 184
 185     if (trigger)
 186         return;
 187     trigger = 1;
 188
 189     OPENSSL_armcap_P = 0;
 190
 191     if ((e = getenv("OPENSSL_armcap"))) {
 192         OPENSSL_armcap_P = (unsigned int)strtoul(e, NULL, 0);
 193         return;
 194     }
 195
 196 # if defined(__APPLE__)
 197 #   if !defined(__aarch64__)
 198     /*
 199      * Capability probing by catching SIGILL appears to be problematic
 200      * on iOS. But since Apple universe is "monocultural", it's actually
 201      * possible to simply set pre-defined processor capability mask.
 202      */
 203     if (1) {
 204         OPENSSL_armcap_P = ARMV7_NEON;
 205         return;
 206     }
 207     /*
 208      * One could do same even for __aarch64__ iOS builds. It's not done
 209      * exclusively for reasons of keeping code unified across platforms.
 210      * Unified code works because it never triggers SIGILL on Apple
 211      * devices...
 212      */
 213 #   else
 214     {
 215         unsigned int sha512;
 216         size_t len = sizeof(sha512);
 217
 218         if (sysctlbyname("hw.optional.armv8_2_sha512", &sha512, &len, NULL, 0) == 0 && sha512 == 1)
 219             OPENSSL_armcap_P |= ARMV8_SHA512;
 220     }
 221 #   endif
 222 # endif
 223
 224 # ifdef OSSL_IMPLEMENT_GETAUXVAL
 225     if (getauxval(HWCAP) & HWCAP_NEON) {
 226         unsigned long hwcap = getauxval(HWCAP_CE);
 227
 228         OPENSSL_armcap_P |= ARMV7_NEON;
 229
 230         if (hwcap & HWCAP_CE_AES)
 231             OPENSSL_armcap_P |= ARMV8_AES;
 232
 233         if (hwcap & HWCAP_CE_PMULL)
 234             OPENSSL_armcap_P |= ARMV8_PMULL;
 235
 236         if (hwcap & HWCAP_CE_SHA1)
 237             OPENSSL_armcap_P |= ARMV8_SHA1;
 238
 239         if (hwcap & HWCAP_CE_SHA256)
 240             OPENSSL_armcap_P |= ARMV8_SHA256;
 241
 242 #  ifdef __aarch64__
 243         if (hwcap & HWCAP_CE_SHA512)
 244             OPENSSL_armcap_P |= ARMV8_SHA512;
 245
 246         if (hwcap & HWCAP_CPUID)
 247             OPENSSL_armcap_P |= ARMV8_CPUID;
 248 #  endif
 249     }
 250 #  ifdef __aarch64__
 251         if (getauxval(HWCAP2) & HWCAP2_RNG)
 252             OPENSSL_armcap_P |= ARMV8_RNG;
 253 #  endif
 254 # endif
 255
 256     sigfillset(&all_masked);
 257     sigdelset(&all_masked, SIGILL);
 258     sigdelset(&all_masked, SIGTRAP);
 259     sigdelset(&all_masked, SIGFPE);
 260     sigdelset(&all_masked, SIGBUS);
 261     sigdelset(&all_masked, SIGSEGV);
 262
 263     memset(&ill_act, 0, sizeof(ill_act));
 264     ill_act.sa_handler = ill_handler;
 265     ill_act.sa_mask = all_masked;
 266
 267     sigprocmask(SIG_SETMASK, &ill_act.sa_mask, &oset);
 268     sigaction(SIGILL, &ill_act, &ill_oact);
 269
 270     /* If we used getauxval, we already have all the values */
 271 # ifndef OSSL_IMPLEMENT_GETAUXVAL
 272     if (sigsetjmp(ill_jmp, 1) == 0) {
 273         _armv7_neon_probe();
 274         OPENSSL_armcap_P |= ARMV7_NEON;
 275         if (sigsetjmp(ill_jmp, 1) == 0) {
 276             _armv8_pmull_probe();
 277             OPENSSL_armcap_P |= ARMV8_PMULL | ARMV8_AES;
 278         } else if (sigsetjmp(ill_jmp, 1) == 0) {
 279             _armv8_aes_probe();
 280             OPENSSL_armcap_P |= ARMV8_AES;
 281         }
 282         if (sigsetjmp(ill_jmp, 1) == 0) {
 283             _armv8_sha1_probe();
 284             OPENSSL_armcap_P |= ARMV8_SHA1;
 285         }
 286         if (sigsetjmp(ill_jmp, 1) == 0) {
 287             _armv8_sha256_probe();
 288             OPENSSL_armcap_P |= ARMV8_SHA256;
 289         }
 290 #  if defined(__aarch64__) && !defined(__APPLE__)
 291         if (sigsetjmp(ill_jmp, 1) == 0) {
 292             _armv8_sha512_probe();
 293             OPENSSL_armcap_P |= ARMV8_SHA512;
 294         }
 295 #  endif
 296     }
 297 #  ifdef __aarch64__
 298     if (sigsetjmp(ill_jmp, 1) == 0) {
 299         _armv8_rng_probe();
 300         OPENSSL_armcap_P |= ARMV8_RNG;
 301     }
 302 #  endif
 303 # endif
 304
 305     /* Things that getauxval didn't tell us */
 306     if (sigsetjmp(ill_jmp, 1) == 0) {
 307         _armv7_tick();
 308         OPENSSL_armcap_P |= ARMV7_TICK;
 309     }
 310
 311     sigaction(SIGILL, &ill_oact, NULL);
 312     sigprocmask(SIG_SETMASK, &oset, NULL);
 313
 314 # ifdef __aarch64__
 315     if (OPENSSL_armcap_P & ARMV8_CPUID)
 316         OPENSSL_arm_midr = _armv8_cpuid_probe();
 317
 318     if ((MIDR_IS_CPU_MODEL(OPENSSL_arm_midr, ARM_CPU_IMP_ARM, ARM_CPU_PART_CORTEX_A72) ||
 319          MIDR_IS_CPU_MODEL(OPENSSL_arm_midr, ARM_CPU_IMP_ARM, ARM_CPU_PART_N1)) &&
 320         (OPENSSL_armcap_P & ARMV7_NEON)) {
 321             OPENSSL_armv8_rsa_neonized = 1;
 322     }
 323 # endif
 324 }
 325 #endif