First Commit

externals/cryptopp/padlkrng.cpp

@@ -0,0 +1,105 @@
+// via-rng.cpp - written and placed in public domain by Jeffrey Walton and Uri Blumenthal.
+
+#include "pch.h"
+#include "config.h"
+#include "cryptlib.h"
+#include "secblock.h"
+#include "padlkrng.h"
+#include "cpu.h"
+
+// The Padlock Security Engine RNG has a few items to be aware of. You can
+// find copies  of the Programmer's manual, Cryptography Research Inc audit
+// report, and other goodies at http://www.cryptopp.com/wiki/VIA_Padlock.
+
+#if CRYPTOPP_MSC_VERSION
+# pragma warning(disable: 4702)
+#endif
+
+NAMESPACE_BEGIN(CryptoPP)
+
+std::string PadlockRNG::AlgorithmProvider() const
+{
+    return "Padlock";
+}
+
+PadlockRNG::PadlockRNG(word32 divisor)
+	: m_divisor(DivisorHelper(divisor)), m_msr(0)
+{
+#if defined(CRYPTOPP_X86_ASM_AVAILABLE)
+	if (!HasPadlockRNG())
+#endif
+		throw PadlockRNG_Err("PadlockRNG", "PadlockRNG generator not available");
+}
+
+void PadlockRNG::GenerateBlock(byte *output, size_t size)
+{
+	CRYPTOPP_UNUSED(output); CRYPTOPP_UNUSED(size);
+#if defined(CRYPTOPP_X86_ASM_AVAILABLE) && defined(__GNUC__)
+	while (size)
+	{
+		__asm__ __volatile__
+		(
+#if (CRYPTOPP_BOOL_X32 || CRYPTOPP_BOOL_X64)
+			"mov  %1, %%rdi          ;\n"
+			"movl %2, %%edx          ;\n"
+#else
+			"mov  %1, %%edi          ;\n"
+			"movl %2, %%edx          ;\n"
+#endif
+
+			// xstore-rng
+			".byte 0x0f, 0xa7, 0xc0  ;\n"
+			"movl %%eax, %0          ;\n"
+
+			: "=g" (m_msr) : "g" (m_buffer.data()), "g" (m_divisor)
+#if (CRYPTOPP_BOOL_X32 || CRYPTOPP_BOOL_X64)
+			: "rax", "rdx", "rdi", "cc"
+#else
+			: "eax", "edx", "edi", "cc"
+#endif
+		);
+
+		const size_t ret = m_msr & 0x1f;
+		const size_t rem = STDMIN<size_t>(ret, STDMIN<size_t>(size, 16U /*buffer size*/));
+		std::memcpy(output, m_buffer, rem);
+		size -= rem; output += rem;
+	}
+#elif defined(CRYPTOPP_X86_ASM_AVAILABLE) && defined(CRYPTOPP_MSC_VERSION) && defined(_M_IX86)
+	while (size)
+	{
+		word32 result, divisor = m_divisor;
+		byte *buffer = reinterpret_cast<byte*>(m_buffer.data());
+		__asm {
+			mov edi, buffer
+			mov edx, divisor
+			_emit 0x0f
+			_emit 0xa7
+			_emit 0xc0
+			mov result, eax
+		}
+
+		const size_t ret = (m_msr = result) & 0x1f;
+		const size_t rem = STDMIN<size_t>(ret, STDMIN<size_t>(size, 16U /*buffer size*/));
+		std::memcpy(output, buffer, rem);
+		size -= rem; output += rem;
+	}
+#else
+	throw PadlockRNG_Err("GenerateBlock", "PadlockRNG generator not available");
+#endif  // CRYPTOPP_X86_ASM_AVAILABLE
+}
+
+void PadlockRNG::DiscardBytes(size_t n)
+{
+	FixedSizeSecBlock<word32, 4> discard;
+	n = RoundUpToMultipleOf(n, sizeof(word32));
+
+	size_t count = STDMIN(n, discard.SizeInBytes());
+	while (count)
+	{
+		GenerateBlock(discard.BytePtr(), count);
+		n -= count;
+		count = STDMIN(n, discard.SizeInBytes());
+	}
+}
+
+NAMESPACE_END