1 files changed, 156 insertions, 0 deletions
diff --git a/CryptoPP/osrng.h b/CryptoPP/osrng.h
new file mode 100644
index 000000000..ae07d057b
--- /dev/null
+++ b/CryptoPP/osrng.h
@@ -0,0 +1,156 @@
+#ifndef CRYPTOPP_OSRNG_H
+#define CRYPTOPP_OSRNG_H
+
+//! \file
+
+#include "config.h"
+
+#ifdef OS_RNG_AVAILABLE
+
+#include "randpool.h"
+#include "rng.h"
+#include "aes.h"
+#include "sha.h"
+#include "fips140.h"
+
+NAMESPACE_BEGIN(CryptoPP)
+
+//! Exception class for Operating-System Random Number Generator.
+class CRYPTOPP_DLL OS_RNG_Err : public Exception
+{
+public:
+	OS_RNG_Err(const std::string &operation);
+};
+
+#ifdef NONBLOCKING_RNG_AVAILABLE
+
+#ifdef CRYPTOPP_WIN32_AVAILABLE
+class CRYPTOPP_DLL MicrosoftCryptoProvider
+{
+public:
+	MicrosoftCryptoProvider();
+	~MicrosoftCryptoProvider();
+#if defined(_WIN64)
+	typedef unsigned __int64 ProviderHandle;	// type HCRYPTPROV, avoid #include <windows.h>
+#else
+	typedef unsigned long ProviderHandle;
+#endif
+	ProviderHandle GetProviderHandle() const {return m_hProvider;}
+private:
+	ProviderHandle m_hProvider;
+};
+
+#pragma comment(lib, "advapi32.lib")
+#endif
+
+//! encapsulate CryptoAPI's CryptGenRandom or /dev/urandom
+class CRYPTOPP_DLL NonblockingRng : public RandomNumberGenerator
+{
+public:
+	NonblockingRng();
+	~NonblockingRng();
+	void GenerateBlock(byte *output, size_t size);
+
+protected:
+#ifdef CRYPTOPP_WIN32_AVAILABLE
+#	ifndef WORKAROUND_MS_BUG_Q258000
+		MicrosoftCryptoProvider m_Provider;
+#	endif
+#else
+	int m_fd;
+#endif
+};
+
+#endif
+
+#ifdef BLOCKING_RNG_AVAILABLE
+
+//! encapsulate /dev/random, or /dev/srandom on OpenBSD
+class CRYPTOPP_DLL BlockingRng : public RandomNumberGenerator
+{
+public:
+	BlockingRng();
+	~BlockingRng();
+	void GenerateBlock(byte *output, size_t size);
+
+protected:
+	int m_fd;
+};
+
+#endif
+
+CRYPTOPP_DLL void CRYPTOPP_API OS_GenerateRandomBlock(bool blocking, byte *output, size_t size);
+
+//! Automaticly Seeded Randomness Pool
+/*! This class seeds itself using an operating system provided RNG. */
+class CRYPTOPP_DLL AutoSeededRandomPool : public RandomPool
+{
+public:
+	//! use blocking to choose seeding with BlockingRng or NonblockingRng. the parameter is ignored if only one of these is available
+	explicit AutoSeededRandomPool(bool blocking = false, unsigned int seedSize = 32)
+		{Reseed(blocking, seedSize);}
+	void Reseed(bool blocking = false, unsigned int seedSize = 32);
+};
+
+//! RNG from ANSI X9.17 Appendix C, seeded using an OS provided RNG
+template <class BLOCK_CIPHER>
+class AutoSeededX917RNG : public RandomNumberGenerator, public NotCopyable
+{
+public:
+	//! use blocking to choose seeding with BlockingRng or NonblockingRng. the parameter is ignored if only one of these is available
+	explicit AutoSeededX917RNG(bool blocking = false, bool autoSeed = true)
+		{if (autoSeed) Reseed(blocking);}
+	void Reseed(bool blocking = false, const byte *additionalEntropy = NULL, size_t length = 0);
+	// exposed for testing
+	void Reseed(const byte *key, size_t keylength, const byte *seed, const byte *timeVector);
+
+	bool CanIncorporateEntropy() const {return true;}
+	void IncorporateEntropy(const byte *input, size_t length) {Reseed(false, input, length);}
+	void GenerateIntoBufferedTransformation(BufferedTransformation &target, const std::string &channel, lword length) {m_rng->GenerateIntoBufferedTransformation(target, channel, length);}
+
+private:
+	member_ptr<RandomNumberGenerator> m_rng;
+};
+
+template <class BLOCK_CIPHER>
+void AutoSeededX917RNG<BLOCK_CIPHER>::Reseed(const byte *key, size_t keylength, const byte *seed, const byte *timeVector)
+{
+	m_rng.reset(new X917RNG(new typename BLOCK_CIPHER::Encryption(key, keylength), seed, timeVector));
+}
+
+template <class BLOCK_CIPHER>
+void AutoSeededX917RNG<BLOCK_CIPHER>::Reseed(bool blocking, const byte *input, size_t length)
+{
+	SecByteBlock seed(BLOCK_CIPHER::BLOCKSIZE + BLOCK_CIPHER::DEFAULT_KEYLENGTH);
+	const byte *key;
+	do
+	{
+		OS_GenerateRandomBlock(blocking, seed, seed.size());
+		if (length > 0)
+		{
+			SHA256 hash;
+			hash.Update(seed, seed.size());
+			hash.Update(input, length);
+			hash.TruncatedFinal(seed, UnsignedMin(hash.DigestSize(), seed.size()));
+		}
+		key = seed + BLOCK_CIPHER::BLOCKSIZE;
+	}	// check that seed and key don't have same value
+	while (memcmp(key, seed, STDMIN((unsigned int)BLOCK_CIPHER::BLOCKSIZE, (unsigned int)BLOCK_CIPHER::DEFAULT_KEYLENGTH)) == 0);
+
+	Reseed(key, BLOCK_CIPHER::DEFAULT_KEYLENGTH, seed, NULL);
+}
+
+CRYPTOPP_DLL_TEMPLATE_CLASS AutoSeededX917RNG<AES>;
+
+//! this is AutoSeededX917RNG\<AES\> in FIPS mode, otherwise it's AutoSeededRandomPool
+#if CRYPTOPP_ENABLE_COMPLIANCE_WITH_FIPS_140_2
+typedef AutoSeededX917RNG<AES> DefaultAutoSeededRNG;
+#else
+typedef AutoSeededRandomPool DefaultAutoSeededRNG;
+#endif
+
+NAMESPACE_END
+
+#endif
+
+#endif