123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219 |
- /* Copyright (c) 2016, Google Inc.
- *
- * Permission to use, copy, modify, and/or distribute this software for any
- * purpose with or without fee is hereby granted, provided that the above
- * copyright notice and this permission notice appear in all copies.
- *
- * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
- * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
- * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
- * SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
- * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
- * OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
- * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. */
- #include <openssl/cpu.h>
- #if defined(OPENSSL_ARM) && !defined(OPENSSL_STATIC_ARMCAP)
- #include <errno.h>
- #include <fcntl.h>
- #include <sys/types.h>
- #include <unistd.h>
- #include <openssl/arm_arch.h>
- #include <openssl/buf.h>
- #include <openssl/mem.h>
- #include "cpu-arm-linux.h"
- #define AT_HWCAP 16
- #define AT_HWCAP2 26
- // |getauxval| is not available on Android until API level 20. Link it as a weak
- // symbol and use other methods as fallback.
- unsigned long getauxval(unsigned long type) __attribute__((weak));
- static int open_eintr(const char *path, int flags) {
- int ret;
- do {
- ret = open(path, flags);
- } while (ret < 0 && errno == EINTR);
- return ret;
- }
- static ssize_t read_eintr(int fd, void *out, size_t len) {
- ssize_t ret;
- do {
- ret = read(fd, out, len);
- } while (ret < 0 && errno == EINTR);
- return ret;
- }
- // read_full reads exactly |len| bytes from |fd| to |out|. On error or end of
- // file, it returns zero.
- static int read_full(int fd, void *out, size_t len) {
- char *outp = out;
- while (len > 0) {
- ssize_t ret = read_eintr(fd, outp, len);
- if (ret <= 0) {
- return 0;
- }
- outp += ret;
- len -= ret;
- }
- return 1;
- }
- // read_file opens |path| and reads until end-of-file. On success, it returns
- // one and sets |*out_ptr| and |*out_len| to a newly-allocated buffer with the
- // contents. Otherwise, it returns zero.
- static int read_file(char **out_ptr, size_t *out_len, const char *path) {
- int fd = open_eintr(path, O_RDONLY);
- if (fd < 0) {
- return 0;
- }
- static const size_t kReadSize = 1024;
- int ret = 0;
- size_t cap = kReadSize, len = 0;
- char *buf = OPENSSL_malloc(cap);
- if (buf == NULL) {
- goto err;
- }
- for (;;) {
- if (cap - len < kReadSize) {
- size_t new_cap = cap * 2;
- if (new_cap < cap) {
- goto err;
- }
- char *new_buf = OPENSSL_realloc(buf, new_cap);
- if (new_buf == NULL) {
- goto err;
- }
- buf = new_buf;
- cap = new_cap;
- }
- ssize_t bytes_read = read_eintr(fd, buf + len, kReadSize);
- if (bytes_read < 0) {
- goto err;
- }
- if (bytes_read == 0) {
- break;
- }
- len += bytes_read;
- }
- *out_ptr = buf;
- *out_len = len;
- ret = 1;
- buf = NULL;
- err:
- OPENSSL_free(buf);
- close(fd);
- return ret;
- }
- // getauxval_proc behaves like |getauxval| but reads from /proc/self/auxv.
- static unsigned long getauxval_proc(unsigned long type) {
- int fd = open_eintr("/proc/self/auxv", O_RDONLY);
- if (fd < 0) {
- return 0;
- }
- struct {
- unsigned long tag;
- unsigned long value;
- } entry;
- for (;;) {
- if (!read_full(fd, &entry, sizeof(entry)) ||
- (entry.tag == 0 && entry.value == 0)) {
- break;
- }
- if (entry.tag == type) {
- close(fd);
- return entry.value;
- }
- }
- close(fd);
- return 0;
- }
- extern uint32_t OPENSSL_armcap_P;
- static int g_has_broken_neon, g_needs_hwcap2_workaround;
- void OPENSSL_cpuid_setup(void) {
- char *cpuinfo_data;
- size_t cpuinfo_len;
- if (!read_file(&cpuinfo_data, &cpuinfo_len, "/proc/cpuinfo")) {
- return;
- }
- STRING_PIECE cpuinfo;
- cpuinfo.data = cpuinfo_data;
- cpuinfo.len = cpuinfo_len;
- // |getauxval| is not available on Android until API level 20. If it is
- // unavailable, read from /proc/self/auxv as a fallback. This is unreadable
- // on some versions of Android, so further fall back to /proc/cpuinfo.
- //
- // See
- // https://android.googlesource.com/platform/ndk/+/882ac8f3392858991a0e1af33b4b7387ec856bd2
- // and b/13679666 (Google-internal) for details.
- unsigned long hwcap = 0;
- if (getauxval != NULL) {
- hwcap = getauxval(AT_HWCAP);
- }
- if (hwcap == 0) {
- hwcap = getauxval_proc(AT_HWCAP);
- }
- if (hwcap == 0) {
- hwcap = crypto_get_arm_hwcap_from_cpuinfo(&cpuinfo);
- }
- // Clear NEON support if known broken.
- g_has_broken_neon = crypto_cpuinfo_has_broken_neon(&cpuinfo);
- if (g_has_broken_neon) {
- hwcap &= ~HWCAP_NEON;
- }
- // Matching OpenSSL, only report other features if NEON is present.
- if (hwcap & HWCAP_NEON) {
- OPENSSL_armcap_P |= ARMV7_NEON;
- // Some ARMv8 Android devices don't expose AT_HWCAP2. Fall back to
- // /proc/cpuinfo. See https://crbug.com/596156.
- unsigned long hwcap2 = 0;
- if (getauxval != NULL) {
- hwcap2 = getauxval(AT_HWCAP2);
- }
- if (hwcap2 == 0) {
- hwcap2 = crypto_get_arm_hwcap2_from_cpuinfo(&cpuinfo);
- g_needs_hwcap2_workaround = hwcap2 != 0;
- }
- if (hwcap2 & HWCAP2_AES) {
- OPENSSL_armcap_P |= ARMV8_AES;
- }
- if (hwcap2 & HWCAP2_PMULL) {
- OPENSSL_armcap_P |= ARMV8_PMULL;
- }
- if (hwcap2 & HWCAP2_SHA1) {
- OPENSSL_armcap_P |= ARMV8_SHA1;
- }
- if (hwcap2 & HWCAP2_SHA2) {
- OPENSSL_armcap_P |= ARMV8_SHA256;
- }
- }
- OPENSSL_free(cpuinfo_data);
- }
- int CRYPTO_has_broken_NEON(void) { return g_has_broken_neon; }
- int CRYPTO_needs_hwcap2_workaround(void) { return g_needs_hwcap2_workaround; }
- #endif // OPENSSL_ARM && !OPENSSL_STATIC_ARMCAP
|