crypto/armcap.c

   1 #include <stdio.h>
   2 #include <stdlib.h>
   3 #include <string.h>
   4 #include <setjmp.h>
   5 #include <signal.h>
   6 #include <openssl/crypto.h>
   7
   8 #include "arm_arch.h"
   9
  10 unsigned int OPENSSL_armcap_P = 0;
  11
  12 #if __ARM_MAX_ARCH__<7
  13 void OPENSSL_cpuid_setup(void)
  14 {
  15 }
  16
  17 unsigned long OPENSSL_rdtsc(void)
  18 {
  19     return 0;
  20 }
  21 #else
  22 static sigset_t all_masked;
  23
  24 static sigjmp_buf ill_jmp;
  25 static void ill_handler(int sig)
  26 {
  27     siglongjmp(ill_jmp, sig);
  28 }
  29
  30 /*
  31  * Following subroutines could have been inlined, but it's not all
  32  * ARM compilers support inline assembler...
  33  */
  34 void _armv7_neon_probe(void);
  35 void _armv8_aes_probe(void);
  36 void _armv8_sha1_probe(void);
  37 void _armv8_sha256_probe(void);
  38 void _armv8_pmull_probe(void);
  39 unsigned long _armv7_tick(void);
  40
  41 unsigned long OPENSSL_rdtsc(void)
  42 {
  43     if (OPENSSL_armcap_P & ARMV7_TICK)
  44         return _armv7_tick();
  45     else
  46         return 0;
  47 }
  48
  49 # if defined(__GNUC__) && __GNUC__>=2
  50 void OPENSSL_cpuid_setup(void) __attribute__ ((constructor));
  51 # endif
  52 /*
  53  * Use a weak reference to getauxval() so we can use it if it is available but
  54  * don't break the build if it is not.
  55  */
  56 # if defined(__GNUC__) && __GNUC__>=2 && defined(__ELF__)
  57 extern unsigned long getauxval(unsigned long type) __attribute__ ((weak));
  58 # else
  59 static unsigned long (*getauxval) (unsigned long) = NULL;
  60 # endif
  61
  62 /*
  63  * ARM puts the the feature bits for Crypto Extensions in AT_HWCAP2, whereas
  64  * AArch64 used AT_HWCAP.
  65  */
  66 # if defined(__arm__) || defined (__arm)
  67 #  define HWCAP                  16
  68                                   /* AT_HWCAP */
  69 #  define HWCAP_NEON             (1 << 12)
  70
  71 #  define HWCAP_CE               26
  72                                   /* AT_HWCAP2 */
  73 #  define HWCAP_CE_AES           (1 << 0)
  74 #  define HWCAP_CE_PMULL         (1 << 1)
  75 #  define HWCAP_CE_SHA1          (1 << 2)
  76 #  define HWCAP_CE_SHA256        (1 << 3)
  77 # elif defined(__aarch64__)
  78 #  define HWCAP                  16
  79                                   /* AT_HWCAP */
  80 #  define HWCAP_NEON             (1 << 1)
  81
  82 #  define HWCAP_CE               HWCAP
  83 #  define HWCAP_CE_AES           (1 << 3)
  84 #  define HWCAP_CE_PMULL         (1 << 4)
  85 #  define HWCAP_CE_SHA1          (1 << 5)
  86 #  define HWCAP_CE_SHA256        (1 << 6)
  87 # endif
  88
  89 void OPENSSL_cpuid_setup(void)
  90 {
  91     char *e;
  92     struct sigaction ill_oact, ill_act;
  93     sigset_t oset;
  94     static int trigger = 0;
  95
  96     if (trigger)
  97         return;
  98     trigger = 1;
  99
 100     if ((e = getenv("OPENSSL_armcap"))) {
 101         OPENSSL_armcap_P = (unsigned int)strtoul(e, NULL, 0);
 102         return;
 103     }
 104
 105     sigfillset(&all_masked);
 106     sigdelset(&all_masked, SIGILL);
 107     sigdelset(&all_masked, SIGTRAP);
 108     sigdelset(&all_masked, SIGFPE);
 109     sigdelset(&all_masked, SIGBUS);
 110     sigdelset(&all_masked, SIGSEGV);
 111
 112     OPENSSL_armcap_P = 0;
 113
 114     memset(&ill_act, 0, sizeof(ill_act));
 115     ill_act.sa_handler = ill_handler;
 116     ill_act.sa_mask = all_masked;
 117
 118     sigprocmask(SIG_SETMASK, &ill_act.sa_mask, &oset);
 119     sigaction(SIGILL, &ill_act, &ill_oact);
 120
 121     if (getauxval != NULL) {
 122         if (getauxval(HWCAP) & HWCAP_NEON) {
 123             unsigned long hwcap = getauxval(HWCAP_CE);
 124
 125             OPENSSL_armcap_P |= ARMV7_NEON;
 126
 127             if (hwcap & HWCAP_CE_AES)
 128                 OPENSSL_armcap_P |= ARMV8_AES;
 129
 130             if (hwcap & HWCAP_CE_PMULL)
 131                 OPENSSL_armcap_P |= ARMV8_PMULL;
 132
 133             if (hwcap & HWCAP_CE_SHA1)
 134                 OPENSSL_armcap_P |= ARMV8_SHA1;
 135
 136             if (hwcap & HWCAP_CE_SHA256)
 137                 OPENSSL_armcap_P |= ARMV8_SHA256;
 138         }
 139     } else if (sigsetjmp(ill_jmp, 1) == 0) {
 140         _armv7_neon_probe();
 141         OPENSSL_armcap_P |= ARMV7_NEON;
 142         if (sigsetjmp(ill_jmp, 1) == 0) {
 143             _armv8_pmull_probe();
 144             OPENSSL_armcap_P |= ARMV8_PMULL | ARMV8_AES;
 145         } else if (sigsetjmp(ill_jmp, 1) == 0) {
 146             _armv8_aes_probe();
 147             OPENSSL_armcap_P |= ARMV8_AES;
 148         }
 149         if (sigsetjmp(ill_jmp, 1) == 0) {
 150             _armv8_sha1_probe();
 151             OPENSSL_armcap_P |= ARMV8_SHA1;
 152         }
 153         if (sigsetjmp(ill_jmp, 1) == 0) {
 154             _armv8_sha256_probe();
 155             OPENSSL_armcap_P |= ARMV8_SHA256;
 156         }
 157     }
 158     if (sigsetjmp(ill_jmp, 1) == 0) {
 159         _armv7_tick();
 160         OPENSSL_armcap_P |= ARMV7_TICK;
 161     }
 162
 163     sigaction(SIGILL, &ill_oact, NULL);
 164     sigprocmask(SIG_SETMASK, &oset, NULL);
 165 }
 166 #endif