diff options
Diffstat (limited to 'lib/cryptopp/osrng.cpp')
-rw-r--r-- | lib/cryptopp/osrng.cpp | 192 |
1 files changed, 192 insertions, 0 deletions
diff --git a/lib/cryptopp/osrng.cpp b/lib/cryptopp/osrng.cpp new file mode 100644 index 000000000..76e486b4e --- /dev/null +++ b/lib/cryptopp/osrng.cpp @@ -0,0 +1,192 @@ +// osrng.cpp - written and placed in the public domain by Wei Dai + +// Thanks to Leonard Janke for the suggestion for AutoSeededRandomPool. + +#include "pch.h" + +#ifndef CRYPTOPP_IMPORTS + +#include "osrng.h" + +#ifdef OS_RNG_AVAILABLE + +#include "rng.h" + +#ifdef CRYPTOPP_WIN32_AVAILABLE +#ifndef _WIN32_WINNT +#define _WIN32_WINNT 0x0400 +#endif +#include <windows.h> +#include <wincrypt.h> +#endif + +#ifdef CRYPTOPP_UNIX_AVAILABLE +#include <errno.h> +#include <fcntl.h> +#include <unistd.h> +#endif + +NAMESPACE_BEGIN(CryptoPP) + +#if defined(NONBLOCKING_RNG_AVAILABLE) || defined(BLOCKING_RNG_AVAILABLE) +OS_RNG_Err::OS_RNG_Err(const std::string &operation) + : Exception(OTHER_ERROR, "OS_Rng: " + operation + " operation failed with error " + +#ifdef CRYPTOPP_WIN32_AVAILABLE + "0x" + IntToString(GetLastError(), 16) +#else + IntToString(errno) +#endif + ) +{ +} +#endif + +#ifdef NONBLOCKING_RNG_AVAILABLE + +#ifdef CRYPTOPP_WIN32_AVAILABLE + +MicrosoftCryptoProvider::MicrosoftCryptoProvider() +{ + if(!CryptAcquireContext(&m_hProvider, 0, 0, PROV_RSA_FULL, CRYPT_VERIFYCONTEXT)) + throw OS_RNG_Err("CryptAcquireContext"); +} + +MicrosoftCryptoProvider::~MicrosoftCryptoProvider() +{ + CryptReleaseContext(m_hProvider, 0); +} + +#endif + +NonblockingRng::NonblockingRng() +{ +#ifndef CRYPTOPP_WIN32_AVAILABLE + m_fd = open("/dev/urandom",O_RDONLY); + if (m_fd == -1) + throw OS_RNG_Err("open /dev/urandom"); +#endif +} + +NonblockingRng::~NonblockingRng() +{ +#ifndef CRYPTOPP_WIN32_AVAILABLE + close(m_fd); +#endif +} + +void NonblockingRng::GenerateBlock(byte *output, size_t size) +{ +#ifdef CRYPTOPP_WIN32_AVAILABLE +# ifdef WORKAROUND_MS_BUG_Q258000 + const MicrosoftCryptoProvider &m_Provider = Singleton<MicrosoftCryptoProvider>().Ref(); +# endif + if (!CryptGenRandom(m_Provider.GetProviderHandle(), (DWORD)size, output)) + throw OS_RNG_Err("CryptGenRandom"); +#else + while (size) + { + ssize_t len = read(m_fd, output, size); + + if (len < 0) + { + // /dev/urandom reads CAN give EAGAIN errors! (maybe EINTR as well) + if (errno != EINTR && errno != EAGAIN) + throw OS_RNG_Err("read /dev/urandom"); + + continue; + } + + output += len; + size -= len; + } +#endif +} + +#endif + +// ************************************************************* + +#ifdef BLOCKING_RNG_AVAILABLE + +#ifndef CRYPTOPP_BLOCKING_RNG_FILENAME +#ifdef __OpenBSD__ +#define CRYPTOPP_BLOCKING_RNG_FILENAME "/dev/srandom" +#else +#define CRYPTOPP_BLOCKING_RNG_FILENAME "/dev/random" +#endif +#endif + +BlockingRng::BlockingRng() +{ + m_fd = open(CRYPTOPP_BLOCKING_RNG_FILENAME,O_RDONLY); + if (m_fd == -1) + throw OS_RNG_Err("open " CRYPTOPP_BLOCKING_RNG_FILENAME); +} + +BlockingRng::~BlockingRng() +{ + close(m_fd); +} + +void BlockingRng::GenerateBlock(byte *output, size_t size) +{ + while (size) + { + // on some systems /dev/random will block until all bytes + // are available, on others it returns immediately + ssize_t len = read(m_fd, output, size); + if (len < 0) + { + // /dev/random reads CAN give EAGAIN errors! (maybe EINTR as well) + if (errno != EINTR && errno != EAGAIN) + throw OS_RNG_Err("read " CRYPTOPP_BLOCKING_RNG_FILENAME); + + continue; + } + + size -= len; + output += len; + if (size) + sleep(1); + } +} + +#endif + +// ************************************************************* + +void OS_GenerateRandomBlock(bool blocking, byte *output, size_t size) +{ +#ifdef NONBLOCKING_RNG_AVAILABLE + if (blocking) +#endif + { +#ifdef BLOCKING_RNG_AVAILABLE + BlockingRng rng; + rng.GenerateBlock(output, size); +#endif + } + +#ifdef BLOCKING_RNG_AVAILABLE + if (!blocking) +#endif + { +#ifdef NONBLOCKING_RNG_AVAILABLE + NonblockingRng rng; + rng.GenerateBlock(output, size); +#endif + } +} + +void AutoSeededRandomPool::Reseed(bool blocking, unsigned int seedSize) +{ + SecByteBlock seed(seedSize); + OS_GenerateRandomBlock(blocking, seed, seedSize); + IncorporateEntropy(seed, seedSize); +} + +NAMESPACE_END + +#endif + +#endif |