| /* 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 |