diff options
Diffstat (limited to 'src/random.cpp')
-rw-r--r-- | src/random.cpp | 44 |
1 files changed, 27 insertions, 17 deletions
diff --git a/src/random.cpp b/src/random.cpp index b0044af514..7e0e94439e 100644 --- a/src/random.cpp +++ b/src/random.cpp @@ -27,15 +27,22 @@ #include <sys/syscall.h> #include <linux/random.h> #endif -#ifdef HAVE_GETENTROPY +#if defined(HAVE_GETENTROPY) || (defined(HAVE_GETENTROPY_RAND) && defined(MAC_OSX)) #include <unistd.h> #endif +#if defined(HAVE_GETENTROPY_RAND) && defined(MAC_OSX) +#include <sys/random.h> +#endif #ifdef HAVE_SYSCTL_ARND #include <sys/sysctl.h> #endif #include <mutex> +#if defined(__x86_64__) || defined(__amd64__) || defined(__i386__) +#include <cpuid.h> +#endif + #include <openssl/err.h> #include <openssl/rand.h> @@ -72,18 +79,9 @@ static bool rdrand_supported = false; static constexpr uint32_t CPUID_F1_ECX_RDRAND = 0x40000000; static void RDRandInit() { - uint32_t eax, ecx, edx; -#if defined(__i386__) && ( defined(__PIC__) || defined(__PIE__)) - // Avoid clobbering ebx, as that is used for PIC on x86. - uint32_t tmp; - __asm__ ("mov %%ebx, %1; cpuid; mov %1, %%ebx": "=a"(eax), "=g"(tmp), "=c"(ecx), "=d"(edx) : "a"(1)); -#else - uint32_t ebx; - __asm__ ("cpuid": "=a"(eax), "=b"(ebx), "=c"(ecx), "=d"(edx) : "a"(1)); -#endif - //! When calling cpuid function #1, ecx register will have this set if RDRAND is available. - if (ecx & CPUID_F1_ECX_RDRAND) { - LogPrintf("Using RdRand as entropy source\n"); + uint32_t eax, ebx, ecx, edx; + if (__get_cpuid(1, &eax, &ebx, &ecx, &edx) && (ecx & CPUID_F1_ECX_RDRAND)) { + LogPrintf("Using RdRand as an additional entropy source\n"); rdrand_supported = true; } hwrand_initialized.store(true); @@ -157,7 +155,7 @@ static void RandAddSeedPerfmon() const size_t nMaxSize = 10000000; // Bail out at more than 10MB of performance data while (true) { nSize = vData.size(); - ret = RegQueryValueExA(HKEY_PERFORMANCE_DATA, "Global", NULL, NULL, vData.data(), &nSize); + ret = RegQueryValueExA(HKEY_PERFORMANCE_DATA, "Global", nullptr, nullptr, vData.data(), &nSize); if (ret != ERROR_MORE_DATA || vData.size() >= nMaxSize) break; vData.resize(std::max((vData.size() * 3) / 2, nMaxSize)); // Grow size of buffer exponentially @@ -191,6 +189,7 @@ void GetDevURandom(unsigned char *ent32) do { ssize_t n = read(f, ent32 + have, NUM_OS_RANDOM_BYTES - have); if (n <= 0 || n + have > NUM_OS_RANDOM_BYTES) { + close(f); RandFailure(); } have += n; @@ -204,7 +203,7 @@ void GetOSRand(unsigned char *ent32) { #if defined(WIN32) HCRYPTPROV hProvider; - int ret = CryptAcquireContextW(&hProvider, NULL, NULL, PROV_RSA_FULL, CRYPT_VERIFYCONTEXT); + int ret = CryptAcquireContextW(&hProvider, nullptr, nullptr, PROV_RSA_FULL, CRYPT_VERIFYCONTEXT); if (!ret) { RandFailure(); } @@ -231,14 +230,25 @@ void GetOSRand(unsigned char *ent32) RandFailure(); } } -#elif defined(HAVE_GETENTROPY) +#elif defined(HAVE_GETENTROPY) && defined(__OpenBSD__) /* On OpenBSD this can return up to 256 bytes of entropy, will return an * error if more are requested. * The call cannot return less than the requested number of bytes. + getentropy is explicitly limited to openbsd here, as a similar (but not + the same) function may exist on other platforms via glibc. */ if (getentropy(ent32, NUM_OS_RANDOM_BYTES) != 0) { RandFailure(); } +#elif defined(HAVE_GETENTROPY_RAND) && defined(MAC_OSX) + // We need a fallback for OSX < 10.12 + if (&getentropy != nullptr) { + if (getentropy(ent32, NUM_OS_RANDOM_BYTES) != 0) { + RandFailure(); + } + } else { + GetDevURandom(ent32); + } #elif defined(HAVE_SYSCTL_ARND) /* FreeBSD and similar. It is possible for the call to return less * bytes than requested, so need to read in a loop. @@ -247,7 +257,7 @@ void GetOSRand(unsigned char *ent32) int have = 0; do { size_t len = NUM_OS_RANDOM_BYTES - have; - if (sysctl(name, ARRAYLEN(name), ent32 + have, &len, NULL, 0) != 0) { + if (sysctl(name, ARRAYLEN(name), ent32 + have, &len, nullptr, 0) != 0) { RandFailure(); } have += len; |