ref: 94f2907dc40a6415a10c252cb9ba3971f1f7e838
dir: /third_party/boringssl/src/crypto/mem.c/
/* Copyright (C) 1995-1998 Eric Young ([email protected])
* All rights reserved.
*
* This package is an SSL implementation written
* by Eric Young ([email protected]).
* The implementation was written so as to conform with Netscapes SSL.
*
* This library is free for commercial and non-commercial use as long as
* the following conditions are aheared to. The following conditions
* apply to all code found in this distribution, be it the RC4, RSA,
* lhash, DES, etc., code; not just the SSL code. The SSL documentation
* included with this distribution is covered by the same copyright terms
* except that the holder is Tim Hudson ([email protected]).
*
* Copyright remains Eric Young's, and as such any Copyright notices in
* the code are not to be removed.
* If this package is used in a product, Eric Young should be given attribution
* as the author of the parts of the library used.
* This can be in the form of a textual message at program startup or
* in documentation (online or textual) provided with the package.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* "This product includes cryptographic software written by
* Eric Young ([email protected])"
* The word 'cryptographic' can be left out if the rouines from the library
* being used are not cryptographic related :-).
* 4. If you include any Windows specific code (or a derivative thereof) from
* the apps directory (application code) you must include an acknowledgement:
* "This product includes software written by Tim Hudson ([email protected])"
*
* THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* The licence and distribution terms for any publically available version or
* derivative of this code cannot be changed. i.e. this code cannot simply be
* copied and put under another distribution licence
* [including the GNU Public Licence.] */
#include <openssl/mem.h>
#include <assert.h>
#include <errno.h>
#include <limits.h>
#include <stdarg.h>
#include <stdio.h>
#include <stdlib.h>
#include <openssl/err.h>
#if defined(OPENSSL_WINDOWS)
OPENSSL_MSVC_PRAGMA(warning(push, 3))
#include <windows.h>
OPENSSL_MSVC_PRAGMA(warning(pop))
#endif
#if defined(BORINGSSL_MALLOC_FAILURE_TESTING)
#include <errno.h>
#include <signal.h>
#include <unistd.h>
#endif
#include "internal.h"
#define OPENSSL_MALLOC_PREFIX 8
static_assert(OPENSSL_MALLOC_PREFIX >= sizeof(size_t), "size_t too large");
#if defined(OPENSSL_ASAN)
void __asan_poison_memory_region(const volatile void *addr, size_t size);
void __asan_unpoison_memory_region(const volatile void *addr, size_t size);
#else
static void __asan_poison_memory_region(const void *addr, size_t size) {}
static void __asan_unpoison_memory_region(const void *addr, size_t size) {}
#endif
// Windows doesn't really support weak symbols as of May 2019, and Clang on
// Windows will emit strong symbols instead. See
// https://bugs.llvm.org/show_bug.cgi?id=37598
//
// EDK2 targets UEFI but builds as ELF and then translates the binary to
// COFF(!). Thus it builds with __ELF__ defined but cannot actually cope with
// weak symbols.
#if !defined(__EDK2_BORINGSSL__) && defined(__ELF__) && defined(__GNUC__)
#define WEAK_SYMBOL_FUNC(rettype, name, args) \
rettype name args __attribute__((weak));
#else
#define WEAK_SYMBOL_FUNC(rettype, name, args) static rettype(*name) args = NULL;
#endif
// sdallocx is a sized |free| function. By passing the size (which we happen to
// always know in BoringSSL), the malloc implementation can save work. We cannot
// depend on |sdallocx| being available, however, so it's a weak symbol.
//
// This will always be safe, but will only be overridden if the malloc
// implementation is statically linked with BoringSSL. So, if |sdallocx| is
// provided in, say, libc.so, we still won't use it because that's dynamically
// linked. This isn't an ideal result, but its helps in some cases.
WEAK_SYMBOL_FUNC(void, sdallocx, (void *ptr, size_t size, int flags));
// The following three functions can be defined to override default heap
// allocation and freeing. If defined, it is the responsibility of
// |OPENSSL_memory_free| to zero out the memory before returning it to the
// system. |OPENSSL_memory_free| will not be passed NULL pointers.
//
// WARNING: These functions are called on every allocation and free in
// BoringSSL across the entire process. They may be called by any code in the
// process which calls BoringSSL, including in process initializers and thread
// destructors. When called, BoringSSL may hold pthreads locks. Any other code
// in the process which, directly or indirectly, calls BoringSSL may be on the
// call stack and may itself be using arbitrary synchronization primitives.
//
// As a result, these functions may not have the usual programming environment
// available to most C or C++ code. In particular, they may not call into
// BoringSSL, or any library which depends on BoringSSL. Any synchronization
// primitives used must tolerate every other synchronization primitive linked
// into the process, including pthreads locks. Failing to meet these constraints
// may result in deadlocks, crashes, or memory corruption.
WEAK_SYMBOL_FUNC(void *, OPENSSL_memory_alloc, (size_t size));
WEAK_SYMBOL_FUNC(void, OPENSSL_memory_free, (void *ptr));
WEAK_SYMBOL_FUNC(size_t, OPENSSL_memory_get_size, (void *ptr));
#if defined(BORINGSSL_MALLOC_FAILURE_TESTING)
static CRYPTO_MUTEX malloc_failure_lock = CRYPTO_MUTEX_INIT;
static uint64_t current_malloc_count = 0;
static uint64_t malloc_number_to_fail = 0;
static int malloc_failure_enabled = 0, break_on_malloc_fail = 0,
any_malloc_failed = 0, disable_malloc_failures = 0;
static void malloc_exit_handler(void) {
CRYPTO_MUTEX_lock_read(&malloc_failure_lock);
if (any_malloc_failed) {
// Signal to the test driver that some allocation failed, so it knows to
// increment the counter and continue.
_exit(88);
}
CRYPTO_MUTEX_unlock_read(&malloc_failure_lock);
}
static void init_malloc_failure(void) {
const char *env = getenv("MALLOC_NUMBER_TO_FAIL");
if (env != NULL && env[0] != 0) {
char *endptr;
malloc_number_to_fail = strtoull(env, &endptr, 10);
if (*endptr == 0) {
malloc_failure_enabled = 1;
atexit(malloc_exit_handler);
}
}
break_on_malloc_fail = getenv("MALLOC_BREAK_ON_FAIL") != NULL;
}
// should_fail_allocation returns one if the current allocation should fail and
// zero otherwise.
static int should_fail_allocation() {
static CRYPTO_once_t once = CRYPTO_ONCE_INIT;
CRYPTO_once(&once, init_malloc_failure);
if (!malloc_failure_enabled || disable_malloc_failures) {
return 0;
}
// We lock just so multi-threaded tests are still correct, but we won't test
// every malloc exhaustively.
CRYPTO_MUTEX_lock_write(&malloc_failure_lock);
int should_fail = current_malloc_count == malloc_number_to_fail;
current_malloc_count++;
any_malloc_failed = any_malloc_failed || should_fail;
CRYPTO_MUTEX_unlock_write(&malloc_failure_lock);
if (should_fail && break_on_malloc_fail) {
raise(SIGTRAP);
}
if (should_fail) {
errno = ENOMEM;
}
return should_fail;
}
void OPENSSL_reset_malloc_counter_for_testing(void) {
CRYPTO_MUTEX_lock_write(&malloc_failure_lock);
current_malloc_count = 0;
CRYPTO_MUTEX_unlock_write(&malloc_failure_lock);
}
void OPENSSL_disable_malloc_failures_for_testing(void) {
CRYPTO_MUTEX_lock_write(&malloc_failure_lock);
BSSL_CHECK(!disable_malloc_failures);
disable_malloc_failures = 1;
CRYPTO_MUTEX_unlock_write(&malloc_failure_lock);
}
void OPENSSL_enable_malloc_failures_for_testing(void) {
CRYPTO_MUTEX_lock_write(&malloc_failure_lock);
BSSL_CHECK(disable_malloc_failures);
disable_malloc_failures = 0;
CRYPTO_MUTEX_unlock_write(&malloc_failure_lock);
}
#else
static int should_fail_allocation(void) { return 0; }
#endif
void *OPENSSL_malloc(size_t size) {
if (should_fail_allocation()) {
goto err;
}
if (OPENSSL_memory_alloc != NULL) {
assert(OPENSSL_memory_free != NULL);
assert(OPENSSL_memory_get_size != NULL);
void *ptr = OPENSSL_memory_alloc(size);
if (ptr == NULL && size != 0) {
goto err;
}
return ptr;
}
if (size + OPENSSL_MALLOC_PREFIX < size) {
goto err;
}
void *ptr = malloc(size + OPENSSL_MALLOC_PREFIX);
if (ptr == NULL) {
goto err;
}
*(size_t *)ptr = size;
__asan_poison_memory_region(ptr, OPENSSL_MALLOC_PREFIX);
return ((uint8_t *)ptr) + OPENSSL_MALLOC_PREFIX;
err:
// This only works because ERR does not call OPENSSL_malloc.
OPENSSL_PUT_ERROR(CRYPTO, ERR_R_MALLOC_FAILURE);
return NULL;
}
void *OPENSSL_zalloc(size_t size) {
void *ret = OPENSSL_malloc(size);
if (ret != NULL) {
OPENSSL_memset(ret, 0, size);
}
return ret;
}
void *OPENSSL_calloc(size_t num, size_t size) {
if (size != 0 && num > SIZE_MAX / size) {
OPENSSL_PUT_ERROR(CRYPTO, ERR_R_OVERFLOW);
return NULL;
}
return OPENSSL_zalloc(num * size);
}
void OPENSSL_free(void *orig_ptr) {
if (orig_ptr == NULL) {
return;
}
if (OPENSSL_memory_free != NULL) {
OPENSSL_memory_free(orig_ptr);
return;
}
void *ptr = ((uint8_t *)orig_ptr) - OPENSSL_MALLOC_PREFIX;
__asan_unpoison_memory_region(ptr, OPENSSL_MALLOC_PREFIX);
size_t size = *(size_t *)ptr;
OPENSSL_cleanse(ptr, size + OPENSSL_MALLOC_PREFIX);
// ASan knows to intercept malloc and free, but not sdallocx.
#if defined(OPENSSL_ASAN)
(void)sdallocx;
free(ptr);
#else
if (sdallocx) {
sdallocx(ptr, size + OPENSSL_MALLOC_PREFIX, 0 /* flags */);
} else {
free(ptr);
}
#endif
}
void *OPENSSL_realloc(void *orig_ptr, size_t new_size) {
if (orig_ptr == NULL) {
return OPENSSL_malloc(new_size);
}
size_t old_size;
if (OPENSSL_memory_get_size != NULL) {
old_size = OPENSSL_memory_get_size(orig_ptr);
} else {
void *ptr = ((uint8_t *)orig_ptr) - OPENSSL_MALLOC_PREFIX;
__asan_unpoison_memory_region(ptr, OPENSSL_MALLOC_PREFIX);
old_size = *(size_t *)ptr;
__asan_poison_memory_region(ptr, OPENSSL_MALLOC_PREFIX);
}
void *ret = OPENSSL_malloc(new_size);
if (ret == NULL) {
return NULL;
}
size_t to_copy = new_size;
if (old_size < to_copy) {
to_copy = old_size;
}
memcpy(ret, orig_ptr, to_copy);
OPENSSL_free(orig_ptr);
return ret;
}
void OPENSSL_cleanse(void *ptr, size_t len) {
#if defined(OPENSSL_WINDOWS)
SecureZeroMemory(ptr, len);
#else
OPENSSL_memset(ptr, 0, len);
#if !defined(OPENSSL_NO_ASM)
/* As best as we can tell, this is sufficient to break any optimisations that
might try to eliminate "superfluous" memsets. If there's an easy way to
detect memset_s, it would be better to use that. */
__asm__ __volatile__("" : : "r"(ptr) : "memory");
#endif
#endif // !OPENSSL_NO_ASM
}
void OPENSSL_clear_free(void *ptr, size_t unused) { OPENSSL_free(ptr); }
int CRYPTO_secure_malloc_init(size_t size, size_t min_size) { return 0; }
int CRYPTO_secure_malloc_initialized(void) { return 0; }
size_t CRYPTO_secure_used(void) { return 0; }
void *OPENSSL_secure_malloc(size_t size) { return OPENSSL_malloc(size); }
void OPENSSL_secure_clear_free(void *ptr, size_t len) {
OPENSSL_clear_free(ptr, len);
}
int CRYPTO_memcmp(const void *in_a, const void *in_b, size_t len) {
const uint8_t *a = in_a;
const uint8_t *b = in_b;
uint8_t x = 0;
for (size_t i = 0; i < len; i++) {
x |= a[i] ^ b[i];
}
return x;
}
uint32_t OPENSSL_hash32(const void *ptr, size_t len) {
// These are the FNV-1a parameters for 32 bits.
static const uint32_t kPrime = 16777619u;
static const uint32_t kOffsetBasis = 2166136261u;
const uint8_t *in = ptr;
uint32_t h = kOffsetBasis;
for (size_t i = 0; i < len; i++) {
h ^= in[i];
h *= kPrime;
}
return h;
}
uint32_t OPENSSL_strhash(const char *s) { return OPENSSL_hash32(s, strlen(s)); }
size_t OPENSSL_strnlen(const char *s, size_t len) {
for (size_t i = 0; i < len; i++) {
if (s[i] == 0) {
return i;
}
}
return len;
}
char *OPENSSL_strdup(const char *s) {
if (s == NULL) {
return NULL;
}
// Copy the NUL terminator.
return OPENSSL_memdup(s, strlen(s) + 1);
}
int OPENSSL_isalpha(int c) {
return (c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z');
}
int OPENSSL_isdigit(int c) { return c >= '0' && c <= '9'; }
int OPENSSL_isxdigit(int c) {
return OPENSSL_isdigit(c) || (c >= 'a' && c <= 'f') || (c >= 'A' && c <= 'F');
}
int OPENSSL_fromxdigit(uint8_t *out, int c) {
if (OPENSSL_isdigit(c)) {
*out = c - '0';
return 1;
}
if ('a' <= c && c <= 'f') {
*out = c - 'a' + 10;
return 1;
}
if ('A' <= c && c <= 'F') {
*out = c - 'A' + 10;
return 1;
}
return 0;
}
int OPENSSL_isalnum(int c) { return OPENSSL_isalpha(c) || OPENSSL_isdigit(c); }
int OPENSSL_tolower(int c) {
if (c >= 'A' && c <= 'Z') {
return c + ('a' - 'A');
}
return c;
}
int OPENSSL_isspace(int c) {
return c == '\t' || c == '\n' || c == '\v' || c == '\f' || c == '\r' ||
c == ' ';
}
int OPENSSL_strcasecmp(const char *a, const char *b) {
for (size_t i = 0;; i++) {
const int aa = OPENSSL_tolower(a[i]);
const int bb = OPENSSL_tolower(b[i]);
if (aa < bb) {
return -1;
} else if (aa > bb) {
return 1;
} else if (aa == 0) {
return 0;
}
}
}
int OPENSSL_strncasecmp(const char *a, const char *b, size_t n) {
for (size_t i = 0; i < n; i++) {
const int aa = OPENSSL_tolower(a[i]);
const int bb = OPENSSL_tolower(b[i]);
if (aa < bb) {
return -1;
} else if (aa > bb) {
return 1;
} else if (aa == 0) {
return 0;
}
}
return 0;
}
int BIO_snprintf(char *buf, size_t n, const char *format, ...) {
va_list args;
va_start(args, format);
int ret = BIO_vsnprintf(buf, n, format, args);
va_end(args);
return ret;
}
int BIO_vsnprintf(char *buf, size_t n, const char *format, va_list args) {
return vsnprintf(buf, n, format, args);
}
int OPENSSL_vasprintf_internal(char **str, const char *format, va_list args,
int system_malloc) {
void *(*allocate)(size_t) = system_malloc ? malloc : OPENSSL_malloc;
void (*deallocate)(void *) = system_malloc ? free : OPENSSL_free;
void *(*reallocate)(void *, size_t) =
system_malloc ? realloc : OPENSSL_realloc;
char *candidate = NULL;
size_t candidate_len = 64; // TODO(bbe) what's the best initial size?
if ((candidate = allocate(candidate_len)) == NULL) {
goto err;
}
va_list args_copy;
va_copy(args_copy, args);
int ret = vsnprintf(candidate, candidate_len, format, args_copy);
va_end(args_copy);
if (ret < 0) {
goto err;
}
if ((size_t)ret >= candidate_len) {
// Too big to fit in allocation.
char *tmp;
candidate_len = (size_t)ret + 1;
if ((tmp = reallocate(candidate, candidate_len)) == NULL) {
goto err;
}
candidate = tmp;
ret = vsnprintf(candidate, candidate_len, format, args);
}
// At this point this should not happen unless vsnprintf is insane.
if (ret < 0 || (size_t)ret >= candidate_len) {
goto err;
}
*str = candidate;
return ret;
err:
deallocate(candidate);
*str = NULL;
errno = ENOMEM;
return -1;
}
int OPENSSL_vasprintf(char **str, const char *format, va_list args) {
return OPENSSL_vasprintf_internal(str, format, args, /*system_malloc=*/0);
}
int OPENSSL_asprintf(char **str, const char *format, ...) {
va_list args;
va_start(args, format);
int ret = OPENSSL_vasprintf(str, format, args);
va_end(args);
return ret;
}
char *OPENSSL_strndup(const char *str, size_t size) {
size = OPENSSL_strnlen(str, size);
size_t alloc_size = size + 1;
if (alloc_size < size) {
// overflow
OPENSSL_PUT_ERROR(CRYPTO, ERR_R_MALLOC_FAILURE);
return NULL;
}
char *ret = OPENSSL_malloc(alloc_size);
if (ret == NULL) {
return NULL;
}
OPENSSL_memcpy(ret, str, size);
ret[size] = '\0';
return ret;
}
size_t OPENSSL_strlcpy(char *dst, const char *src, size_t dst_size) {
size_t l = 0;
for (; dst_size > 1 && *src; dst_size--) {
*dst++ = *src++;
l++;
}
if (dst_size) {
*dst = 0;
}
return l + strlen(src);
}
size_t OPENSSL_strlcat(char *dst, const char *src, size_t dst_size) {
size_t l = 0;
for (; dst_size > 0 && *dst; dst_size--, dst++) {
l++;
}
return l + OPENSSL_strlcpy(dst, src, dst_size);
}
void *OPENSSL_memdup(const void *data, size_t size) {
if (size == 0) {
return NULL;
}
void *ret = OPENSSL_malloc(size);
if (ret == NULL) {
return NULL;
}
OPENSSL_memcpy(ret, data, size);
return ret;
}
void *CRYPTO_malloc(size_t size, const char *file, int line) {
return OPENSSL_malloc(size);
}
void *CRYPTO_realloc(void *ptr, size_t new_size, const char *file, int line) {
return OPENSSL_realloc(ptr, new_size);
}
void CRYPTO_free(void *ptr, const char *file, int line) { OPENSSL_free(ptr); }