diff options
Diffstat (limited to 'source/luametatex/source/libraries/mimalloc/src/random.c')
| -rw-r--r-- | source/luametatex/source/libraries/mimalloc/src/random.c | 162 |
1 files changed, 6 insertions, 156 deletions
diff --git a/source/luametatex/source/libraries/mimalloc/src/random.c b/source/luametatex/source/libraries/mimalloc/src/random.c index 06d4ba4ad..4fc8b2f8f 100644 --- a/source/luametatex/source/libraries/mimalloc/src/random.c +++ b/source/luametatex/source/libraries/mimalloc/src/random.c @@ -4,14 +4,10 @@ This is free software; you can redistribute it and/or modify it under the terms of the MIT license. A copy of the license can be found in the file "LICENSE" at the root of this distribution. -----------------------------------------------------------------------------*/ -#ifndef _DEFAULT_SOURCE -#define _DEFAULT_SOURCE // for syscall() on Linux -#endif - #include "mimalloc.h" -#include "mimalloc-internal.h" - -#include <string.h> // memset +#include "mimalloc/internal.h" +#include "mimalloc/prim.h" // _mi_prim_random_buf +#include <string.h> // memset /* ---------------------------------------------------------------------------- We use our own PRNG to keep predictable performance of random number generation @@ -158,159 +154,13 @@ uintptr_t _mi_random_next(mi_random_ctx_t* ctx) { /* ---------------------------------------------------------------------------- -To initialize a fresh random context we rely on the OS: -- Windows : BCryptGenRandom (or RtlGenRandom) -- macOS : CCRandomGenerateBytes, arc4random_buf -- bsd,wasi : arc4random_buf -- Linux : getrandom,/dev/urandom +To initialize a fresh random context. If we cannot get good randomness, we fall back to weak randomness based on a timer and ASLR. -----------------------------------------------------------------------------*/ -#if defined(_WIN32) - -#if defined(MI_USE_RTLGENRANDOM) // || defined(__cplusplus) -// We prefer to use BCryptGenRandom instead of (the unofficial) RtlGenRandom but when using -// dynamic overriding, we observed it can raise an exception when compiled with C++, and -// sometimes deadlocks when also running under the VS debugger. -// In contrast, issue #623 implies that on Windows Server 2019 we need to use BCryptGenRandom. -// To be continued.. -#pragma comment (lib,"advapi32.lib") -#define RtlGenRandom SystemFunction036 -#ifdef __cplusplus -extern "C" { -#endif -BOOLEAN NTAPI RtlGenRandom(PVOID RandomBuffer, ULONG RandomBufferLength); -#ifdef __cplusplus -} -#endif -static bool os_random_buf(void* buf, size_t buf_len) { - return (RtlGenRandom(buf, (ULONG)buf_len) != 0); -} -#else - -#ifndef BCRYPT_USE_SYSTEM_PREFERRED_RNG -#define BCRYPT_USE_SYSTEM_PREFERRED_RNG 0x00000002 -#endif - -typedef LONG (NTAPI *PBCryptGenRandom)(HANDLE, PUCHAR, ULONG, ULONG); -static PBCryptGenRandom pBCryptGenRandom = NULL; - -static bool os_random_buf(void* buf, size_t buf_len) { - if (pBCryptGenRandom == NULL) { - HINSTANCE hDll = LoadLibrary(TEXT("bcrypt.dll")); - if (hDll != NULL) { - pBCryptGenRandom = (PBCryptGenRandom)(void (*)(void))GetProcAddress(hDll, "BCryptGenRandom"); - } - } - if (pBCryptGenRandom == NULL) { - return false; - } - else { - return (pBCryptGenRandom(NULL, (PUCHAR)buf, (ULONG)buf_len, BCRYPT_USE_SYSTEM_PREFERRED_RNG) >= 0); - } -} -#endif - -#elif defined(__APPLE__) -#include <AvailabilityMacros.h> -#if defined(MAC_OS_X_VERSION_10_10) && MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_10 -#include <CommonCrypto/CommonCryptoError.h> -#include <CommonCrypto/CommonRandom.h> -#endif -static bool os_random_buf(void* buf, size_t buf_len) { - #if defined(MAC_OS_X_VERSION_10_15) && MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_15 - // We prefere CCRandomGenerateBytes as it returns an error code while arc4random_buf - // may fail silently on macOS. See PR #390, and <https://opensource.apple.com/source/Libc/Libc-1439.40.11/gen/FreeBSD/arc4random.c.auto.html> - return (CCRandomGenerateBytes(buf, buf_len) == kCCSuccess); - #else - // fall back on older macOS - arc4random_buf(buf, buf_len); - return true; - #endif -} - -#elif defined(__ANDROID__) || defined(__DragonFly__) || \ - defined(__FreeBSD__) || defined(__NetBSD__) || defined(__OpenBSD__) || \ - defined(__sun) // todo: what to use with __wasi__? -#include <stdlib.h> -static bool os_random_buf(void* buf, size_t buf_len) { - arc4random_buf(buf, buf_len); - return true; -} -#elif defined(__linux__) || defined(__HAIKU__) -#if defined(__linux__) -#include <sys/syscall.h> -#endif -#include <unistd.h> -#include <sys/types.h> -#include <sys/stat.h> -#include <fcntl.h> -#include <errno.h> -static bool os_random_buf(void* buf, size_t buf_len) { - // Modern Linux provides `getrandom` but different distributions either use `sys/random.h` or `linux/random.h` - // and for the latter the actual `getrandom` call is not always defined. - // (see <https://stackoverflow.com/questions/45237324/why-doesnt-getrandom-compile>) - // We therefore use a syscall directly and fall back dynamically to /dev/urandom when needed. -#ifdef SYS_getrandom - #ifndef GRND_NONBLOCK - #define GRND_NONBLOCK (1) - #endif - static _Atomic(uintptr_t) no_getrandom; // = 0 - if (mi_atomic_load_acquire(&no_getrandom)==0) { - ssize_t ret = syscall(SYS_getrandom, buf, buf_len, GRND_NONBLOCK); - if (ret >= 0) return (buf_len == (size_t)ret); - if (errno != ENOSYS) return false; - mi_atomic_store_release(&no_getrandom, 1UL); // don't call again, and fall back to /dev/urandom - } -#endif - int flags = O_RDONLY; - #if defined(O_CLOEXEC) - flags |= O_CLOEXEC; - #endif - int fd = open("/dev/urandom", flags, 0); - if (fd < 0) return false; - size_t count = 0; - while(count < buf_len) { - ssize_t ret = read(fd, (char*)buf + count, buf_len - count); - if (ret<=0) { - if (errno!=EAGAIN && errno!=EINTR) break; - } - else { - count += ret; - } - } - close(fd); - return (count==buf_len); -} -#else -static bool os_random_buf(void* buf, size_t buf_len) { - return false; -} -#endif - -#if defined(_WIN32) -#include <windows.h> -#elif defined(__APPLE__) -#include <mach/mach_time.h> -#else -#include <time.h> -#endif - uintptr_t _mi_os_random_weak(uintptr_t extra_seed) { uintptr_t x = (uintptr_t)&_mi_os_random_weak ^ extra_seed; // ASLR makes the address random - - #if defined(_WIN32) - LARGE_INTEGER pcount; - QueryPerformanceCounter(&pcount); - x ^= (uintptr_t)(pcount.QuadPart); - #elif defined(__APPLE__) - x ^= (uintptr_t)mach_absolute_time(); - #else - struct timespec time; - clock_gettime(CLOCK_MONOTONIC, &time); - x ^= (uintptr_t)time.tv_sec; - x ^= (uintptr_t)time.tv_nsec; - #endif + x ^= _mi_prim_clock_now(); // and do a few randomization steps uintptr_t max = ((x ^ (x >> 17)) & 0x0F) + 1; for (uintptr_t i = 0; i < max; i++) { @@ -322,7 +172,7 @@ uintptr_t _mi_os_random_weak(uintptr_t extra_seed) { static void mi_random_init_ex(mi_random_ctx_t* ctx, bool use_weak) { uint8_t key[32]; - if (use_weak || !os_random_buf(key, sizeof(key))) { + if (use_weak || !_mi_prim_random_buf(key, sizeof(key))) { // if we fail to get random data from the OS, we fall back to a // weak random source based on the current time #if !defined(__wasi__) |