ref: bfe9da47cfa2f51ebef78c59332b5ba2deba306d
dir: /third_party/boringssl/src/crypto/mem.c/
/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com) * All rights reserved. * * This package is an SSL implementation written * by Eric Young (eay@cryptsoft.com). * 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 (tjh@cryptsoft.com). * * 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 (eay@cryptsoft.com)" * 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 (tjh@cryptsoft.com)" * * 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 <stdarg.h> #include <stdio.h> #include <openssl/err.h> #if defined(OPENSSL_WINDOWS) OPENSSL_MSVC_PRAGMA(warning(push, 3)) #include <windows.h> OPENSSL_MSVC_PRAGMA(warning(pop)) #endif #include "internal.h" #define OPENSSL_MALLOC_PREFIX 8 OPENSSL_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 #if 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)); // kBoringSSLBinaryTag is a distinctive byte sequence to identify binaries that // are linking in BoringSSL and, roughly, what version they are using. static const uint8_t kBoringSSLBinaryTag[18] = { // 16 bytes of magic tag. 0x8c, 0x62, 0x20, 0x0b, 0xd2, 0xa0, 0x72, 0x58, 0x44, 0xa8, 0x96, 0x69, 0xad, 0x55, 0x7e, 0xec, // Current source iteration. Incremented ~monthly. 1, 0, }; void *OPENSSL_malloc(size_t size) { if (OPENSSL_memory_alloc != NULL) { assert(OPENSSL_memory_free != NULL); assert(OPENSSL_memory_get_size != NULL); return OPENSSL_memory_alloc(size); } if (size + OPENSSL_MALLOC_PREFIX < size) { // |OPENSSL_malloc| is a central function in BoringSSL thus a reference to // |kBoringSSLBinaryTag| is created here so that the tag isn't discarded by // the linker. The following is sufficient to stop GCC, Clang, and MSVC // optimising away the reference at the time of writing. Since this // probably results in an actual memory reference, it is put in this very // rare code path. uint8_t unused = *(volatile uint8_t *)kBoringSSLBinaryTag; (void) unused; return NULL; } void *ptr = malloc(size + OPENSSL_MALLOC_PREFIX); if (ptr == NULL) { return NULL; } *(size_t *)ptr = size; __asan_poison_memory_region(ptr, OPENSSL_MALLOC_PREFIX); return ((uint8_t *)ptr) + OPENSSL_MALLOC_PREFIX; } 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); if (sdallocx) { sdallocx(ptr, size + OPENSSL_MALLOC_PREFIX, 0 /* flags */); } else { free(ptr); } } 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_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; } const size_t len = strlen(s) + 1; char *ret = OPENSSL_malloc(len); if (ret == NULL) { return NULL; } OPENSSL_memcpy(ret, s, len); return ret; } int OPENSSL_tolower(int c) { if (c >= 'A' && c <= 'Z') { return c + ('a' - 'A'); } return 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); } 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) { OPENSSL_PUT_ERROR(CRYPTO, ERR_R_MALLOC_FAILURE); 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) { OPENSSL_PUT_ERROR(CRYPTO, ERR_R_MALLOC_FAILURE); 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); }