diff options
Diffstat (limited to 'json-c/random_seed.c')
| -rw-r--r-- | json-c/random_seed.c | 237 |
1 files changed, 0 insertions, 237 deletions
diff --git a/json-c/random_seed.c b/json-c/random_seed.c deleted file mode 100644 index f671929..0000000 --- a/json-c/random_seed.c +++ /dev/null @@ -1,237 +0,0 @@ -/* - * random_seed.c - * - * Copyright (c) 2013 Metaparadigm Pte. Ltd. - * Michael Clark <michael@metaparadigm.com> - * - * This library is free software; you can redistribute it and/or modify - * it under the terms of the MIT license. See COPYING for details. - * - */ - -#include <stdio.h> -#include "config.h" - -#define DEBUG_SEED(s) - - -#if defined ENABLE_RDRAND - -/* cpuid */ - -#if defined __GNUC__ && (defined __i386__ || defined __x86_64__) -#define HAS_X86_CPUID 1 - -static void do_cpuid(int regs[], int h) -{ - __asm__ __volatile__( -#if defined __x86_64__ - "pushq %%rbx;\n" -#else - "pushl %%ebx;\n" -#endif - "cpuid;\n" -#if defined __x86_64__ - "popq %%rbx;\n" -#else - "popl %%ebx;\n" -#endif - : "=a"(regs[0]), [ebx] "=r"(regs[1]), "=c"(regs[2]), "=d"(regs[3]) - : "a"(h)); -} - -#elif defined _MSC_VER - -#define HAS_X86_CPUID 1 -#define do_cpuid __cpuid - -#endif - -/* has_rdrand */ - -#if HAS_X86_CPUID - -static int has_rdrand() -{ - // CPUID.01H:ECX.RDRAND[bit 30] == 1 - int regs[4]; - do_cpuid(regs, 1); - return (regs[2] & (1 << 30)) != 0; -} - -#endif - -/* get_rdrand_seed - GCC x86 and X64 */ - -#if defined __GNUC__ && (defined __i386__ || defined __x86_64__) - -#define HAVE_RDRAND 1 - -static int get_rdrand_seed() -{ - DEBUG_SEED("get_rdrand_seed"); - int _eax; - // rdrand eax - __asm__ __volatile__("1: .byte 0x0F\n" - " .byte 0xC7\n" - " .byte 0xF0\n" - " jnc 1b;\n" - : "=a" (_eax)); - return _eax; -} - -#endif - -#if defined _MSC_VER - -#if _MSC_VER >= 1700 -#define HAVE_RDRAND 1 - -/* get_rdrand_seed - Visual Studio 2012 and above */ - -static int get_rdrand_seed() -{ - DEBUG_SEED("get_rdrand_seed"); - int r; - while (_rdrand32_step(&r) == 0); - return r; -} - -#elif defined _M_IX86 -#define HAVE_RDRAND 1 - -/* get_rdrand_seed - Visual Studio 2010 and below - x86 only */ - -static int get_rdrand_seed() -{ - DEBUG_SEED("get_rdrand_seed"); - int _eax; -retry: - // rdrand eax - __asm _emit 0x0F __asm _emit 0xC7 __asm _emit 0xF0 - __asm jnc retry - __asm mov _eax, eax - return _eax; -} - -#endif -#endif - -#endif /* defined ENABLE_RDRAND */ - - -/* has_dev_urandom */ - -#if defined (__APPLE__) || defined(__unix__) || defined(__linux__) - -#include <string.h> -#include <fcntl.h> -#include <unistd.h> -#include <errno.h> -#include <stdlib.h> -#include <sys/stat.h> - -#define HAVE_DEV_RANDOM 1 - -static const char *dev_random_file = "/dev/urandom"; - -static int has_dev_urandom() -{ - struct stat buf; - if (stat(dev_random_file, &buf)) { - return 0; - } - return ((buf.st_mode & S_IFCHR) != 0); -} - - -/* get_dev_random_seed */ - -static int get_dev_random_seed() -{ - DEBUG_SEED("get_dev_random_seed"); - - int fd = open(dev_random_file, O_RDONLY); - if (fd < 0) { - fprintf(stderr, "error opening %s: %s", dev_random_file, strerror(errno)); - exit(1); - } - - int r; - ssize_t nread = read(fd, &r, sizeof(r)); - if (nread != sizeof(r)) { - fprintf(stderr, "error short read %s: %s", dev_random_file, strerror(errno)); - exit(1); - } - - close(fd); - return r; -} - -#endif - - -/* get_cryptgenrandom_seed */ - -#ifdef WIN32 - -#define HAVE_CRYPTGENRANDOM 1 - -#include <windows.h> -#include <wincrypt.h> -#ifndef __GNUC__ -#pragma comment(lib, "advapi32.lib") -#endif - -static int get_cryptgenrandom_seed() -{ - DEBUG_SEED("get_cryptgenrandom_seed"); - - HCRYPTPROV hProvider = 0; - int r; - - if (!CryptAcquireContextW(&hProvider, 0, 0, PROV_RSA_FULL, CRYPT_VERIFYCONTEXT | CRYPT_SILENT)) { - fprintf(stderr, "error CryptAcquireContextW"); - exit(1); - } - - if (!CryptGenRandom(hProvider, sizeof(r), (BYTE*)&r)) { - fprintf(stderr, "error CryptGenRandom"); - exit(1); - } - - CryptReleaseContext(hProvider, 0); - - return r; -} - -#endif - - -/* get_time_seed */ - -#include <time.h> - -static int get_time_seed() -{ - DEBUG_SEED("get_time_seed"); - - return (int)time(NULL) * 433494437; -} - - -/* json_c_get_random_seed */ - -int json_c_get_random_seed() -{ -#if HAVE_RDRAND - if (has_rdrand()) return get_rdrand_seed(); -#endif -#if HAVE_DEV_RANDOM - if (has_dev_urandom()) return get_dev_random_seed(); -#endif -#if HAVE_CRYPTGENRANDOM - return get_cryptgenrandom_seed(); -#endif - return get_time_seed(); -} |