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/* hwf-arm.c - Detect hardware features - ARM part
* Copyright (C) 2013,2019 Jussi Kivilinna <jussi.kivilinna@iki.fi>
*
* This file is part of Libgcrypt.
*
* Libgcrypt is free software; you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as
* published by the Free Software Foundation; either version 2.1 of
* the License, or (at your option) any later version.
*
* Libgcrypt 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 Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
*/
#include <config.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <stdarg.h>
#include <unistd.h>
#include <errno.h>
#if defined(HAVE_SYS_AUXV_H) && (defined(HAVE_GETAUXVAL) || \
defined(HAVE_ELF_AUX_INFO))
#include <sys/auxv.h>
#endif
#include "g10lib.h"
#include "hwf-common.h"
#if !defined (__arm__) && !defined (__aarch64__)
# error Module build for wrong CPU.
#endif
#if defined(HAVE_SYS_AUXV_H) && defined(HAVE_ELF_AUX_INFO) && \
!defined(HAVE_GETAUXVAL) && defined(AT_HWCAP)
#define HAVE_GETAUXVAL
static unsigned long getauxval(unsigned long type)
{
unsigned long auxval = 0;
int err;
/* FreeBSD provides 'elf_aux_info' function that does the same as
* 'getauxval' on Linux. */
err = elf_aux_info (type, &auxval, sizeof(auxval));
if (err)
{
errno = err;
auxval = 0;
}
return auxval;
}
#endif
#undef HAS_SYS_AT_HWCAP
#if defined(__linux__) || \
(defined(HAVE_SYS_AUXV_H) && defined(HAVE_GETAUXVAL))
#define HAS_SYS_AT_HWCAP 1
struct feature_map_s {
unsigned int hwcap_flag;
unsigned int hwcap2_flag;
const char *feature_match;
unsigned int hwf_flag;
};
#ifdef __arm__
/* Note: These macros have same values on Linux and FreeBSD. */
#ifndef AT_HWCAP
# define AT_HWCAP 16
#endif
#ifndef AT_HWCAP2
# define AT_HWCAP2 26
#endif
#ifndef HWCAP_NEON
# define HWCAP_NEON 4096
#endif
#ifndef HWCAP2_AES
# define HWCAP2_AES 1
#endif
#ifndef HWCAP2_PMULL
# define HWCAP2_PMULL 2
#endif
#ifndef HWCAP2_SHA1
# define HWCAP2_SHA1 4
#endif
#ifndef HWCAP2_SHA2
# define HWCAP2_SHA2 8
#endif
static const struct feature_map_s arm_features[] =
{
#ifdef ENABLE_NEON_SUPPORT
{ HWCAP_NEON, 0, " neon", HWF_ARM_NEON },
#endif
#ifdef ENABLE_ARM_CRYPTO_SUPPORT
{ 0, HWCAP2_AES, " aes", HWF_ARM_AES },
{ 0, HWCAP2_SHA1," sha1", HWF_ARM_SHA1 },
{ 0, HWCAP2_SHA2, " sha2", HWF_ARM_SHA2 },
{ 0, HWCAP2_PMULL, " pmull", HWF_ARM_PMULL },
#endif
};
#elif defined(__aarch64__)
/* Note: These macros have same values on Linux and FreeBSD. */
#ifndef AT_HWCAP
# define AT_HWCAP 16
#endif
#ifndef AT_HWCAP2
# define AT_HWCAP2 -1
#endif
#ifndef HWCAP_ASIMD
# define HWCAP_ASIMD 2
#endif
#ifndef HWCAP_AES
# define HWCAP_AES 8
#endif
#ifndef HWCAP_PMULL
# define HWCAP_PMULL 16
#endif
#ifndef HWCAP_SHA1
# define HWCAP_SHA1 32
#endif
#ifndef HWCAP_SHA2
# define HWCAP_SHA2 64
#endif
static const struct feature_map_s arm_features[] =
{
#ifdef ENABLE_NEON_SUPPORT
{ HWCAP_ASIMD, 0, " asimd", HWF_ARM_NEON },
#endif
#ifdef ENABLE_ARM_CRYPTO_SUPPORT
{ HWCAP_AES, 0, " aes", HWF_ARM_AES },
{ HWCAP_SHA1, 0, " sha1", HWF_ARM_SHA1 },
{ HWCAP_SHA2, 0, " sha2", HWF_ARM_SHA2 },
{ HWCAP_PMULL, 0, " pmull", HWF_ARM_PMULL },
#endif
};
#endif
static int
get_hwcap(unsigned int *hwcap, unsigned int *hwcap2)
{
struct { unsigned long a_type; unsigned long a_val; } auxv;
FILE *f;
int err = -1;
static int hwcap_initialized = 0;
static unsigned int stored_hwcap = 0;
static unsigned int stored_hwcap2 = 0;
if (hwcap_initialized)
{
*hwcap = stored_hwcap;
*hwcap2 = stored_hwcap2;
return 0;
}
#if defined(HAVE_SYS_AUXV_H) && defined(HAVE_GETAUXVAL)
errno = 0;
auxv.a_val = getauxval (AT_HWCAP);
if (errno == 0)
{
stored_hwcap |= auxv.a_val;
hwcap_initialized = 1;
}
if (AT_HWCAP2 >= 0)
{
errno = 0;
auxv.a_val = getauxval (AT_HWCAP2);
if (errno == 0)
{
stored_hwcap2 |= auxv.a_val;
hwcap_initialized = 1;
}
}
if (hwcap_initialized && (stored_hwcap || stored_hwcap2))
{
*hwcap = stored_hwcap;
*hwcap2 = stored_hwcap2;
return 0;
}
#endif
f = fopen("/proc/self/auxv", "r");
if (!f)
{
*hwcap = stored_hwcap;
*hwcap2 = stored_hwcap2;
return -1;
}
while (fread(&auxv, sizeof(auxv), 1, f) > 0)
{
if (auxv.a_type == AT_HWCAP)
{
stored_hwcap |= auxv.a_val;
hwcap_initialized = 1;
}
if (auxv.a_type == AT_HWCAP2)
{
stored_hwcap2 |= auxv.a_val;
hwcap_initialized = 1;
}
}
if (hwcap_initialized)
err = 0;
fclose(f);
*hwcap = stored_hwcap;
*hwcap2 = stored_hwcap2;
return err;
}
static unsigned int
detect_arm_at_hwcap(void)
{
unsigned int hwcap;
unsigned int hwcap2;
unsigned int features = 0;
unsigned int i;
if (get_hwcap(&hwcap, &hwcap2) < 0)
return features;
for (i = 0; i < DIM(arm_features); i++)
{
if (hwcap & arm_features[i].hwcap_flag)
features |= arm_features[i].hwf_flag;
if (hwcap2 & arm_features[i].hwcap2_flag)
features |= arm_features[i].hwf_flag;
}
return features;
}
#endif
#undef HAS_PROC_CPUINFO
#ifdef __linux__
#define HAS_PROC_CPUINFO 1
static unsigned int
detect_arm_proc_cpuinfo(unsigned int *broken_hwfs)
{
char buf[1024]; /* large enough */
char *str_features, *str_feat;
int cpu_implementer, cpu_arch, cpu_variant, cpu_part, cpu_revision;
FILE *f;
int readlen, i;
size_t mlen;
static int cpuinfo_initialized = 0;
static unsigned int stored_cpuinfo_features;
static unsigned int stored_broken_hwfs;
struct {
const char *name;
int *value;
} cpu_entries[5] = {
{ "CPU implementer", &cpu_implementer },
{ "CPU architecture", &cpu_arch },
{ "CPU variant", &cpu_variant },
{ "CPU part", &cpu_part },
{ "CPU revision", &cpu_revision },
};
if (cpuinfo_initialized)
{
*broken_hwfs |= stored_broken_hwfs;
return stored_cpuinfo_features;
}
f = fopen("/proc/cpuinfo", "r");
if (!f)
return 0;
memset (buf, 0, sizeof(buf));
readlen = fread (buf, 1, sizeof(buf), f);
fclose (f);
if (readlen <= 0 || readlen > sizeof(buf))
return 0;
buf[sizeof(buf) - 1] = '\0';
cpuinfo_initialized = 1;
stored_cpuinfo_features = 0;
stored_broken_hwfs = 0;
/* Find features line. */
str_features = strstr(buf, "Features");
if (!str_features)
return stored_cpuinfo_features;
/* Find CPU version information. */
for (i = 0; i < DIM(cpu_entries); i++)
{
char *str;
*cpu_entries[i].value = -1;
str = strstr(buf, cpu_entries[i].name);
if (!str)
continue;
str = strstr(str, ": ");
if (!str)
continue;
str += 2;
if (strcmp(cpu_entries[i].name, "CPU architecture") == 0
&& strcmp(str, "AArch64") == 0)
*cpu_entries[i].value = 8;
else
*cpu_entries[i].value = strtoul(str, NULL, 0);
}
/* Lines to strings. */
for (i = 0; i < sizeof(buf); i++)
if (buf[i] == '\n')
buf[i] = '\0';
/* Check features. */
for (i = 0; i < DIM(arm_features); i++)
{
str_feat = strstr(str_features, arm_features[i].feature_match);
if (str_feat)
{
mlen = strlen(arm_features[i].feature_match);
if (str_feat[mlen] == ' ' || str_feat[mlen] == '\0')
{
stored_cpuinfo_features |= arm_features[i].hwf_flag;
}
}
}
/* Check for CPUs with broken NEON implementation. See
*/
if (cpu_implementer == 0x51
&& cpu_arch == 7
&& cpu_variant == 1
&& cpu_part == 0x4d
&& cpu_revision == 0)
{
stored_broken_hwfs = HWF_ARM_NEON;
}
*broken_hwfs |= stored_broken_hwfs;
return stored_cpuinfo_features;
}
#endif /* __linux__ */
unsigned int
_gcry_hwf_detect_arm (void)
{
unsigned int ret = 0;
unsigned int broken_hwfs = 0;
#if defined (HAS_SYS_AT_HWCAP)
ret |= detect_arm_at_hwcap ();
#endif
#if defined (HAS_PROC_CPUINFO)
ret |= detect_arm_proc_cpuinfo (&broken_hwfs);
#endif
#if defined(__ARM_NEON) && defined(ENABLE_NEON_SUPPORT)
ret |= HWF_ARM_NEON;
#endif
ret &= ~broken_hwfs;
return ret;
}