David Benjamin | 4969cc9 | 2016-04-22 15:02:23 -0400 | [diff] [blame] | 1 | /* Copyright (c) 2016, Google Inc. |
| 2 | * |
| 3 | * Permission to use, copy, modify, and/or distribute this software for any |
| 4 | * purpose with or without fee is hereby granted, provided that the above |
| 5 | * copyright notice and this permission notice appear in all copies. |
| 6 | * |
| 7 | * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES |
| 8 | * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF |
| 9 | * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY |
| 10 | * SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES |
| 11 | * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION |
| 12 | * OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN |
| 13 | * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. */ |
| 14 | |
| 15 | #include <openssl/cpu.h> |
| 16 | |
Robert Sloan | 726e9d1 | 2018-09-11 11:45:04 -0700 | [diff] [blame] | 17 | #if defined(OPENSSL_ARM) && !defined(OPENSSL_STATIC_ARMCAP) |
David Benjamin | 4969cc9 | 2016-04-22 15:02:23 -0400 | [diff] [blame] | 18 | #include <errno.h> |
| 19 | #include <fcntl.h> |
David Benjamin | 4969cc9 | 2016-04-22 15:02:23 -0400 | [diff] [blame] | 20 | #include <sys/types.h> |
| 21 | #include <unistd.h> |
| 22 | |
| 23 | #include <openssl/arm_arch.h> |
| 24 | #include <openssl/buf.h> |
| 25 | #include <openssl/mem.h> |
| 26 | |
Robert Sloan | c9abfe4 | 2018-11-26 12:19:07 -0800 | [diff] [blame^] | 27 | #include "cpu-arm-linux.h" |
David Benjamin | 4969cc9 | 2016-04-22 15:02:23 -0400 | [diff] [blame] | 28 | |
| 29 | #define AT_HWCAP 16 |
| 30 | #define AT_HWCAP2 26 |
| 31 | |
Robert Sloan | 8f860b1 | 2017-08-28 07:37:06 -0700 | [diff] [blame] | 32 | // |getauxval| is not available on Android until API level 20. Link it as a weak |
| 33 | // symbol and use other methods as fallback. |
David Benjamin | 4969cc9 | 2016-04-22 15:02:23 -0400 | [diff] [blame] | 34 | unsigned long getauxval(unsigned long type) __attribute__((weak)); |
| 35 | |
| 36 | static int open_eintr(const char *path, int flags) { |
| 37 | int ret; |
| 38 | do { |
| 39 | ret = open(path, flags); |
| 40 | } while (ret < 0 && errno == EINTR); |
| 41 | return ret; |
| 42 | } |
| 43 | |
| 44 | static ssize_t read_eintr(int fd, void *out, size_t len) { |
| 45 | ssize_t ret; |
| 46 | do { |
| 47 | ret = read(fd, out, len); |
| 48 | } while (ret < 0 && errno == EINTR); |
| 49 | return ret; |
| 50 | } |
| 51 | |
Robert Sloan | 8f860b1 | 2017-08-28 07:37:06 -0700 | [diff] [blame] | 52 | // read_full reads exactly |len| bytes from |fd| to |out|. On error or end of |
| 53 | // file, it returns zero. |
David Benjamin | 4969cc9 | 2016-04-22 15:02:23 -0400 | [diff] [blame] | 54 | static int read_full(int fd, void *out, size_t len) { |
| 55 | char *outp = out; |
| 56 | while (len > 0) { |
| 57 | ssize_t ret = read_eintr(fd, outp, len); |
| 58 | if (ret <= 0) { |
| 59 | return 0; |
| 60 | } |
| 61 | outp += ret; |
| 62 | len -= ret; |
| 63 | } |
| 64 | return 1; |
| 65 | } |
| 66 | |
Robert Sloan | 8f860b1 | 2017-08-28 07:37:06 -0700 | [diff] [blame] | 67 | // read_file opens |path| and reads until end-of-file. On success, it returns |
| 68 | // one and sets |*out_ptr| and |*out_len| to a newly-allocated buffer with the |
| 69 | // contents. Otherwise, it returns zero. |
David Benjamin | 4969cc9 | 2016-04-22 15:02:23 -0400 | [diff] [blame] | 70 | static int read_file(char **out_ptr, size_t *out_len, const char *path) { |
| 71 | int fd = open_eintr(path, O_RDONLY); |
| 72 | if (fd < 0) { |
| 73 | return 0; |
| 74 | } |
| 75 | |
| 76 | static const size_t kReadSize = 1024; |
| 77 | int ret = 0; |
| 78 | size_t cap = kReadSize, len = 0; |
| 79 | char *buf = OPENSSL_malloc(cap); |
| 80 | if (buf == NULL) { |
| 81 | goto err; |
| 82 | } |
| 83 | |
| 84 | for (;;) { |
| 85 | if (cap - len < kReadSize) { |
| 86 | size_t new_cap = cap * 2; |
| 87 | if (new_cap < cap) { |
| 88 | goto err; |
| 89 | } |
| 90 | char *new_buf = OPENSSL_realloc(buf, new_cap); |
| 91 | if (new_buf == NULL) { |
| 92 | goto err; |
| 93 | } |
| 94 | buf = new_buf; |
| 95 | cap = new_cap; |
| 96 | } |
| 97 | |
| 98 | ssize_t bytes_read = read_eintr(fd, buf + len, kReadSize); |
| 99 | if (bytes_read < 0) { |
| 100 | goto err; |
| 101 | } |
| 102 | if (bytes_read == 0) { |
| 103 | break; |
| 104 | } |
| 105 | len += bytes_read; |
| 106 | } |
| 107 | |
| 108 | *out_ptr = buf; |
| 109 | *out_len = len; |
| 110 | ret = 1; |
| 111 | buf = NULL; |
| 112 | |
| 113 | err: |
| 114 | OPENSSL_free(buf); |
| 115 | close(fd); |
| 116 | return ret; |
| 117 | } |
| 118 | |
Robert Sloan | 8f860b1 | 2017-08-28 07:37:06 -0700 | [diff] [blame] | 119 | // getauxval_proc behaves like |getauxval| but reads from /proc/self/auxv. |
David Benjamin | 4969cc9 | 2016-04-22 15:02:23 -0400 | [diff] [blame] | 120 | static unsigned long getauxval_proc(unsigned long type) { |
| 121 | int fd = open_eintr("/proc/self/auxv", O_RDONLY); |
| 122 | if (fd < 0) { |
| 123 | return 0; |
| 124 | } |
| 125 | |
| 126 | struct { |
| 127 | unsigned long tag; |
| 128 | unsigned long value; |
| 129 | } entry; |
| 130 | |
| 131 | for (;;) { |
| 132 | if (!read_full(fd, &entry, sizeof(entry)) || |
| 133 | (entry.tag == 0 && entry.value == 0)) { |
| 134 | break; |
| 135 | } |
| 136 | if (entry.tag == type) { |
| 137 | close(fd); |
| 138 | return entry.value; |
| 139 | } |
| 140 | } |
| 141 | close(fd); |
| 142 | return 0; |
| 143 | } |
| 144 | |
David Benjamin | 4969cc9 | 2016-04-22 15:02:23 -0400 | [diff] [blame] | 145 | extern uint32_t OPENSSL_armcap_P; |
| 146 | |
Robert Sloan | db4251a | 2017-09-18 09:38:15 -0700 | [diff] [blame] | 147 | static int g_has_broken_neon, g_needs_hwcap2_workaround; |
David Benjamin | 4969cc9 | 2016-04-22 15:02:23 -0400 | [diff] [blame] | 148 | |
| 149 | void OPENSSL_cpuid_setup(void) { |
| 150 | char *cpuinfo_data; |
| 151 | size_t cpuinfo_len; |
| 152 | if (!read_file(&cpuinfo_data, &cpuinfo_len, "/proc/cpuinfo")) { |
| 153 | return; |
| 154 | } |
| 155 | STRING_PIECE cpuinfo; |
| 156 | cpuinfo.data = cpuinfo_data; |
| 157 | cpuinfo.len = cpuinfo_len; |
| 158 | |
Robert Sloan | 8f860b1 | 2017-08-28 07:37:06 -0700 | [diff] [blame] | 159 | // |getauxval| is not available on Android until API level 20. If it is |
| 160 | // unavailable, read from /proc/self/auxv as a fallback. This is unreadable |
| 161 | // on some versions of Android, so further fall back to /proc/cpuinfo. |
| 162 | // |
| 163 | // See |
| 164 | // https://android.googlesource.com/platform/ndk/+/882ac8f3392858991a0e1af33b4b7387ec856bd2 |
| 165 | // and b/13679666 (Google-internal) for details. |
David Benjamin | 4969cc9 | 2016-04-22 15:02:23 -0400 | [diff] [blame] | 166 | unsigned long hwcap = 0; |
| 167 | if (getauxval != NULL) { |
| 168 | hwcap = getauxval(AT_HWCAP); |
| 169 | } |
| 170 | if (hwcap == 0) { |
| 171 | hwcap = getauxval_proc(AT_HWCAP); |
| 172 | } |
| 173 | if (hwcap == 0) { |
Robert Sloan | 726e9d1 | 2018-09-11 11:45:04 -0700 | [diff] [blame] | 174 | hwcap = crypto_get_arm_hwcap_from_cpuinfo(&cpuinfo); |
David Benjamin | 4969cc9 | 2016-04-22 15:02:23 -0400 | [diff] [blame] | 175 | } |
| 176 | |
Robert Sloan | 8f860b1 | 2017-08-28 07:37:06 -0700 | [diff] [blame] | 177 | // Clear NEON support if known broken. |
Robert Sloan | 726e9d1 | 2018-09-11 11:45:04 -0700 | [diff] [blame] | 178 | g_has_broken_neon = crypto_cpuinfo_has_broken_neon(&cpuinfo); |
David Benjamin | 4969cc9 | 2016-04-22 15:02:23 -0400 | [diff] [blame] | 179 | if (g_has_broken_neon) { |
| 180 | hwcap &= ~HWCAP_NEON; |
| 181 | } |
| 182 | |
Robert Sloan | 8f860b1 | 2017-08-28 07:37:06 -0700 | [diff] [blame] | 183 | // Matching OpenSSL, only report other features if NEON is present. |
David Benjamin | 4969cc9 | 2016-04-22 15:02:23 -0400 | [diff] [blame] | 184 | if (hwcap & HWCAP_NEON) { |
| 185 | OPENSSL_armcap_P |= ARMV7_NEON; |
| 186 | |
Robert Sloan | 8f860b1 | 2017-08-28 07:37:06 -0700 | [diff] [blame] | 187 | // Some ARMv8 Android devices don't expose AT_HWCAP2. Fall back to |
| 188 | // /proc/cpuinfo. See https://crbug.com/596156. |
David Benjamin | 4969cc9 | 2016-04-22 15:02:23 -0400 | [diff] [blame] | 189 | unsigned long hwcap2 = 0; |
| 190 | if (getauxval != NULL) { |
| 191 | hwcap2 = getauxval(AT_HWCAP2); |
| 192 | } |
| 193 | if (hwcap2 == 0) { |
Robert Sloan | 726e9d1 | 2018-09-11 11:45:04 -0700 | [diff] [blame] | 194 | hwcap2 = crypto_get_arm_hwcap2_from_cpuinfo(&cpuinfo); |
Robert Sloan | db4251a | 2017-09-18 09:38:15 -0700 | [diff] [blame] | 195 | g_needs_hwcap2_workaround = hwcap2 != 0; |
David Benjamin | 4969cc9 | 2016-04-22 15:02:23 -0400 | [diff] [blame] | 196 | } |
| 197 | |
| 198 | if (hwcap2 & HWCAP2_AES) { |
| 199 | OPENSSL_armcap_P |= ARMV8_AES; |
| 200 | } |
| 201 | if (hwcap2 & HWCAP2_PMULL) { |
| 202 | OPENSSL_armcap_P |= ARMV8_PMULL; |
| 203 | } |
| 204 | if (hwcap2 & HWCAP2_SHA1) { |
| 205 | OPENSSL_armcap_P |= ARMV8_SHA1; |
| 206 | } |
| 207 | if (hwcap2 & HWCAP2_SHA2) { |
| 208 | OPENSSL_armcap_P |= ARMV8_SHA256; |
| 209 | } |
| 210 | } |
| 211 | |
| 212 | OPENSSL_free(cpuinfo_data); |
| 213 | } |
| 214 | |
| 215 | int CRYPTO_has_broken_NEON(void) { return g_has_broken_neon; } |
| 216 | |
Robert Sloan | db4251a | 2017-09-18 09:38:15 -0700 | [diff] [blame] | 217 | int CRYPTO_needs_hwcap2_workaround(void) { return g_needs_hwcap2_workaround; } |
| 218 | |
Robert Sloan | 8f860b1 | 2017-08-28 07:37:06 -0700 | [diff] [blame] | 219 | #endif // OPENSSL_ARM && !OPENSSL_STATIC_ARMCAP |