1 files changed, 165 insertions, 0 deletions

diff --git a/CryptoPP/pubkey.cpp b/CryptoPP/pubkey.cpp
new file mode 100644
index 000000000..1159e5343
--- /dev/null
+++ b/CryptoPP/pubkey.cpp
@@ -0,0 +1,165 @@
+// pubkey.cpp - written and placed in the public domain by Wei Dai
+
+#include "pch.h"
+
+#ifndef CRYPTOPP_IMPORTS
+
+#include "pubkey.h"
+
+NAMESPACE_BEGIN(CryptoPP)
+
+void P1363_MGF1KDF2_Common(HashTransformation &hash, byte *output, size_t outputLength, const byte *input, size_t inputLength, const byte *derivationParams, size_t derivationParamsLength, bool mask, unsigned int counterStart)
+{
+	ArraySink *sink;
+	HashFilter filter(hash, sink = mask ? new ArrayXorSink(output, outputLength) : new ArraySink(output, outputLength));
+	word32 counter = counterStart;
+	while (sink->AvailableSize() > 0)
+	{
+		filter.Put(input, inputLength);
+		filter.PutWord32(counter++);
+		filter.Put(derivationParams, derivationParamsLength);
+		filter.MessageEnd();
+	}
+}
+
+bool PK_DeterministicSignatureMessageEncodingMethod::VerifyMessageRepresentative(
+	HashTransformation &hash, HashIdentifier hashIdentifier, bool messageEmpty,
+	byte *representative, size_t representativeBitLength) const
+{
+	SecByteBlock computedRepresentative(BitsToBytes(representativeBitLength));
+	ComputeMessageRepresentative(NullRNG(), NULL, 0, hash, hashIdentifier, messageEmpty, computedRepresentative, representativeBitLength);
+	return VerifyBufsEqual(representative, computedRepresentative, computedRepresentative.size());
+}
+
+bool PK_RecoverableSignatureMessageEncodingMethod::VerifyMessageRepresentative(
+	HashTransformation &hash, HashIdentifier hashIdentifier, bool messageEmpty,
+	byte *representative, size_t representativeBitLength) const
+{
+	SecByteBlock recoveredMessage(MaxRecoverableLength(representativeBitLength, hashIdentifier.second, hash.DigestSize()));
+	DecodingResult result = RecoverMessageFromRepresentative(
+		hash, hashIdentifier, messageEmpty, representative, representativeBitLength, recoveredMessage);
+	return result.isValidCoding && result.messageLength == 0;
+}
+
+void TF_SignerBase::InputRecoverableMessage(PK_MessageAccumulator &messageAccumulator, const byte *recoverableMessage, size_t recoverableMessageLength) const
+{
+	PK_MessageAccumulatorBase &ma = static_cast<PK_MessageAccumulatorBase &>(messageAccumulator);
+	HashIdentifier id = GetHashIdentifier();
+	const MessageEncodingInterface &encoding = GetMessageEncodingInterface();
+
+	if (MessageRepresentativeBitLength() < encoding.MinRepresentativeBitLength(id.second, ma.AccessHash().DigestSize()))
+		throw PK_SignatureScheme::KeyTooShort();
+
+	size_t maxRecoverableLength = encoding.MaxRecoverableLength(MessageRepresentativeBitLength(), GetHashIdentifier().second, ma.AccessHash().DigestSize());
+
+	if (maxRecoverableLength == 0)
+		{throw NotImplemented("TF_SignerBase: this algorithm does not support messsage recovery or the key is too short");}
+	if (recoverableMessageLength > maxRecoverableLength)
+		throw InvalidArgument("TF_SignerBase: the recoverable message part is too long for the given key and algorithm");
+
+	ma.m_recoverableMessage.Assign(recoverableMessage, recoverableMessageLength);
+	encoding.ProcessRecoverableMessage(
+		ma.AccessHash(), 
+		recoverableMessage, recoverableMessageLength,
+		NULL, 0, ma.m_semisignature);
+}
+
+size_t TF_SignerBase::SignAndRestart(RandomNumberGenerator &rng, PK_MessageAccumulator &messageAccumulator, byte *signature, bool restart) const
+{
+	PK_MessageAccumulatorBase &ma = static_cast<PK_MessageAccumulatorBase &>(messageAccumulator);
+	HashIdentifier id = GetHashIdentifier();
+	const MessageEncodingInterface &encoding = GetMessageEncodingInterface();
+
+	if (MessageRepresentativeBitLength() < encoding.MinRepresentativeBitLength(id.second, ma.AccessHash().DigestSize()))
+		throw PK_SignatureScheme::KeyTooShort();
+
+	SecByteBlock representative(MessageRepresentativeLength());
+	encoding.ComputeMessageRepresentative(rng, 
+		ma.m_recoverableMessage, ma.m_recoverableMessage.size(), 
+		ma.AccessHash(), id, ma.m_empty,
+		representative, MessageRepresentativeBitLength());
+	ma.m_empty = true;
+
+	Integer r(representative, representative.size());
+	size_t signatureLength = SignatureLength();
+	GetTrapdoorFunctionInterface().CalculateRandomizedInverse(rng, r).Encode(signature, signatureLength);
+	return signatureLength;
+}
+
+void TF_VerifierBase::InputSignature(PK_MessageAccumulator &messageAccumulator, const byte *signature, size_t signatureLength) const
+{
+	PK_MessageAccumulatorBase &ma = static_cast<PK_MessageAccumulatorBase &>(messageAccumulator);
+	HashIdentifier id = GetHashIdentifier();
+	const MessageEncodingInterface &encoding = GetMessageEncodingInterface();
+
+	if (MessageRepresentativeBitLength() < encoding.MinRepresentativeBitLength(id.second, ma.AccessHash().DigestSize()))
+		throw PK_SignatureScheme::KeyTooShort();
+
+	ma.m_representative.New(MessageRepresentativeLength());
+	Integer x = GetTrapdoorFunctionInterface().ApplyFunction(Integer(signature, signatureLength));
+	if (x.BitCount() > MessageRepresentativeBitLength())
+		x = Integer::Zero();	// don't return false here to prevent timing attack
+	x.Encode(ma.m_representative, ma.m_representative.size());
+}
+
+bool TF_VerifierBase::VerifyAndRestart(PK_MessageAccumulator &messageAccumulator) const
+{
+	PK_MessageAccumulatorBase &ma = static_cast<PK_MessageAccumulatorBase &>(messageAccumulator);
+	HashIdentifier id = GetHashIdentifier();
+	const MessageEncodingInterface &encoding = GetMessageEncodingInterface();
+
+	if (MessageRepresentativeBitLength() < encoding.MinRepresentativeBitLength(id.second, ma.AccessHash().DigestSize()))
+		throw PK_SignatureScheme::KeyTooShort();
+
+	bool result = encoding.VerifyMessageRepresentative(
+		ma.AccessHash(), id, ma.m_empty, ma.m_representative, MessageRepresentativeBitLength());
+	ma.m_empty = true;
+	return result;
+}
+
+DecodingResult TF_VerifierBase::RecoverAndRestart(byte *recoveredMessage, PK_MessageAccumulator &messageAccumulator) const
+{
+	PK_MessageAccumulatorBase &ma = static_cast<PK_MessageAccumulatorBase &>(messageAccumulator);
+	HashIdentifier id = GetHashIdentifier();
+	const MessageEncodingInterface &encoding = GetMessageEncodingInterface();
+
+	if (MessageRepresentativeBitLength() < encoding.MinRepresentativeBitLength(id.second, ma.AccessHash().DigestSize()))
+		throw PK_SignatureScheme::KeyTooShort();
+
+	DecodingResult result = encoding.RecoverMessageFromRepresentative(
+		ma.AccessHash(), id, ma.m_empty, ma.m_representative, MessageRepresentativeBitLength(), recoveredMessage);
+	ma.m_empty = true;
+	return result;
+}
+
+DecodingResult TF_DecryptorBase::Decrypt(RandomNumberGenerator &rng, const byte *ciphertext, size_t ciphertextLength, byte *plaintext, const NameValuePairs &parameters) const
+{
+	if (ciphertextLength != FixedCiphertextLength())
+			throw InvalidArgument(AlgorithmName() + ": ciphertext length of " + IntToString(ciphertextLength) + " doesn't match the required length of " + IntToString(FixedCiphertextLength()) + " for this key");
+
+	SecByteBlock paddedBlock(PaddedBlockByteLength());
+	Integer x = GetTrapdoorFunctionInterface().CalculateInverse(rng, Integer(ciphertext, ciphertextLength));
+	if (x.ByteCount() > paddedBlock.size())
+		x = Integer::Zero();	// don't return false here to prevent timing attack
+	x.Encode(paddedBlock, paddedBlock.size());
+	return GetMessageEncodingInterface().Unpad(paddedBlock, PaddedBlockBitLength(), plaintext, parameters);
+}
+
+void TF_EncryptorBase::Encrypt(RandomNumberGenerator &rng, const byte *plaintext, size_t plaintextLength, byte *ciphertext, const NameValuePairs &parameters) const
+{
+	if (plaintextLength > FixedMaxPlaintextLength())
+	{
+		if (FixedMaxPlaintextLength() < 1)
+			throw InvalidArgument(AlgorithmName() + ": this key is too short to encrypt any messages");
+		else
+			throw InvalidArgument(AlgorithmName() + ": message length of " + IntToString(plaintextLength) + " exceeds the maximum of " + IntToString(FixedMaxPlaintextLength()) + " for this public key");
+	}
+
+	SecByteBlock paddedBlock(PaddedBlockByteLength());
+	GetMessageEncodingInterface().Pad(rng, plaintext, plaintextLength, paddedBlock, PaddedBlockBitLength(), parameters);
+	GetTrapdoorFunctionInterface().ApplyRandomizedFunction(rng, Integer(paddedBlock, paddedBlock.size())).Encode(ciphertext, FixedCiphertextLength());
+}
+
+NAMESPACE_END
+
+#endif