// pubkey.h - written and placed in the public domain by Wei Dai
#ifndef CRYPTOPP_PUBKEY_H
#define CRYPTOPP_PUBKEY_H
/** \file
This file contains helper classes/functions for implementing public key algorithms.
The class hierachies in this .h file tend to look like this:
<pre>
x1
/ \
y1 z1
| |
x2<y1> x2<z1>
| |
y2 z2
| |
x3<y2> x3<z2>
| |
y3 z3
</pre>
- x1, y1, z1 are abstract interface classes defined in cryptlib.h
- x2, y2, z2 are implementations of the interfaces using "abstract policies", which
are pure virtual functions that should return interfaces to interchangeable algorithms.
These classes have "Base" suffixes.
- x3, y3, z3 hold actual algorithms and implement those virtual functions.
These classes have "Impl" suffixes.
The "TF_" prefix means an implementation using trapdoor functions on integers.
The "DL_" prefix means an implementation using group operations (in groups where discrete log is hard).
*/
#include "modarith.h"
#include "filters.h"
#include "eprecomp.h"
#include "fips140.h"
#include "argnames.h"
#include <memory>
// VC60 workaround: this macro is defined in shlobj.h and conflicts with a template parameter used in this file
#undef INTERFACE
NAMESPACE_BEGIN(CryptoPP)
//! _
class CRYPTOPP_DLL CRYPTOPP_NO_VTABLE TrapdoorFunctionBounds
{
public:
virtual ~TrapdoorFunctionBounds() {}
virtual Integer PreimageBound() const =0;
virtual Integer ImageBound() const =0;
virtual Integer MaxPreimage() const {return --PreimageBound();}
virtual Integer MaxImage() const {return --ImageBound();}
};
//! _
class CRYPTOPP_DLL CRYPTOPP_NO_VTABLE RandomizedTrapdoorFunction : public TrapdoorFunctionBounds
{
public:
virtual Integer ApplyRandomizedFunction(RandomNumberGenerator &rng, const Integer &x) const =0;
virtual bool IsRandomized() const {return true;}
};
//! _
class CRYPTOPP_DLL CRYPTOPP_NO_VTABLE TrapdoorFunction : public RandomizedTrapdoorFunction
{
public:
Integer ApplyRandomizedFunction(RandomNumberGenerator &rng, const Integer &x) const
{return ApplyFunction(x);}
bool IsRandomized() const {return false;}
virtual Integer ApplyFunction(const Integer &x) const =0;
};
//! _
class CRYPTOPP_DLL CRYPTOPP_NO_VTABLE RandomizedTrapdoorFunctionInverse
{
public:
virtual ~RandomizedTrapdoorFunctionInverse() {}
virtual Integer CalculateRandomizedInverse(RandomNumberGenerator &rng, const Integer &x) const =0;
virtual bool IsRandomized() const {return true;}
};
//! _
class CRYPTOPP_DLL CRYPTOPP_NO_VTABLE TrapdoorFunctionInverse : public RandomizedTrapdoorFunctionInverse
{
public:
virtual ~TrapdoorFunctionInverse() {}
Integer CalculateRandomizedInverse(RandomNumberGenerator &rng, const Integer &x) const
{return CalculateInverse(rng, x);}
bool IsRandomized() const {return false;}
virtual Integer CalculateInverse(RandomNumberGenerator &rng, const Integer &x) const =0;
};
// ********************************************************
//! message encoding method for public key encryption
class CRYPTOPP_NO_VTABLE PK_EncryptionMessageEncodingMethod
{
public:
virtual ~PK_EncryptionMessageEncodingMethod() {}
virtual bool ParameterSupported(const char *name) const {return false;}
//! max size of unpadded message in bytes, given max size of padded message in bits (1 less than size of modulus)
virtual size_t MaxUnpaddedLength(size_t paddedLength) const =0;
virtual void Pad(RandomNumberGenerator &rng, const byte *raw, size_t inputLength, byte *padded, size_t paddedBitLength, const NameValuePairs ¶meters) const =0;
virtual DecodingResult Unpad(const byte *padded, size_t paddedBitLength, byte *raw, const NameValuePairs ¶meters) const =0;
};
// ********************************************************
//! _
template <class TFI, class MEI>
class CRYPTOPP_NO_VTABLE TF_Base
{
protected:
virtual const TrapdoorFunctionBounds & GetTrapdoorFunctionBounds() const =0;
typedef TFI TrapdoorFunctionInterface;
virtual const TrapdoorFunctionInterface & GetTrapdoorFunctionInterface() const =0;
typedef MEI MessageEncodingInterface;
virtual const MessageEncodingInterface & GetMessageEncodingInterface() const =0;
};
// ********************************************************
//! _
template <class BASE>
class CRYPTOPP_NO_VTABLE PK_FixedLengthCryptoSystemImpl : public BASE
{
public:
size_t MaxPlaintextLength(size_t ciphertextLength) const
{return ciphertextLength == FixedCiphertextLength() ? FixedMaxPlaintextLength() : 0;}
size_t CiphertextLength(size_t plaintextLength) const
{return plaintextLength <= FixedMaxPlaintextLength() ? FixedCiphertextLength() : 0;}
virtual size_t FixedMaxPlaintextLength() const =0;
virtual size_t FixedCiphertextLength() const =0;
};
//! _
template <class INTERFACE, class BASE>
class CRYPTOPP_NO_VTABLE TF_CryptoSystemBase : public PK_FixedLengthCryptoSystemImpl<INTERFACE>, protected BASE
{
public:
bool ParameterSupported(const char *name) const {return this->GetMessageEncodingInterface().ParameterSupported(name);}
size_t FixedMaxPlaintextLength() const {return this->GetMessageEncodingInterface().MaxUnpaddedLength(PaddedBlockBitLength());}
size_t FixedCiphertextLength() const {return this->GetTrapdoorFunctionBounds().MaxImage().ByteCount();}
protected:
size_t PaddedBlockByteLength() const {return BitsToBytes(PaddedBlockBitLength());}
size_t PaddedBlockBitLength() const {return this->GetTrapdoorFunctionBounds().PreimageBound().BitCount()-1;}
};
//! _
class CRYPTOPP_DLL CRYPTOPP_NO_VTABLE TF_DecryptorBase : public TF_CryptoSystemBase<PK_Decryptor, TF_Base<TrapdoorFunctionInverse, PK_EncryptionMessageEncodingMethod> >
{
public:
DecodingResult Decrypt(RandomNumberGenerator &rng, const byte *ciphertext, size_t ciphertextLength, byte *plaintext, const NameValuePairs ¶meters = g_nullNameValuePairs) const;
};
//! _
class CRYPTOPP_DLL CRYPTOPP_NO_VTABLE TF_EncryptorBase : public TF_CryptoSystemBase<PK_Encryptor, TF_Base<RandomizedTrapdoorFunction, PK_EncryptionMessageEncodingMethod> >
{
public:
void Encrypt(RandomNumberGenerator &rng, const byte *plaintext, size_t plaintextLength, byte *ciphertext, const NameValuePairs ¶meters = g_nullNameValuePairs) const;
};
// ********************************************************
typedef std::pair<const byte *, size_t> HashIdentifier;
//! interface for message encoding method for public key signature schemes
class CRYPTOPP_NO_VTABLE PK_SignatureMessageEncodingMethod
{
public:
virtual ~PK_SignatureMessageEncodingMethod() {}
virtual size_t MinRepresentativeBitLength(size_t hashIdentifierLength, size_t digestLength) const
{return 0;}
virtual size_t MaxRecoverableLength(size_t representativeBitLength, size_t hashIdentifierLength, size_t digestLength) const
{return 0;}
bool IsProbabilistic() const
{return true;}
bool AllowNonrecoverablePart() const
{throw NotImplemented("PK_MessageEncodingMethod: this signature scheme does not support message recovery");}
virtual bool RecoverablePartFirst() const
{throw NotImplemented("PK_MessageEncodingMethod: this signature scheme does not support message recovery");}
// for verification, DL
virtual void ProcessSemisignature(HashTransformation &hash, const byte *semisignature, size_t semisignatureLength) const {}
// for signature
virtual void ProcessRecoverableMessage(HashTransformation &hash,
const byte *recoverableMessage, size_t recoverableMessageLength,
const byte *presignature, size_t presignatureLength,
SecByteBlock &semisignature) const
{
if (RecoverablePartFirst())
assert(!"ProcessRecoverableMessage() not implemented");
}
virtual void ComputeMessageRepresentative(RandomNumberGenerator &rng,
const byte *recoverableMessage, size_t recoverableMessageLength,
HashTransformation &hash, HashIdentifier hashIdentifier, bool messageEmpty,
byte *representative, size_t representativeBitLength) const =0;
virtual bool VerifyMessageRepresentative(
HashTransformation &hash, HashIdentifier hashIdentifier, bool messageEmpty,
byte *representative, size_t representativeBitLength) const =0;
virtual DecodingResult RecoverMessageFromRepresentative( // for TF
HashTransformation &hash, HashIdentifier hashIdentifier, bool messageEmpty,
byte *representative, size_t representativeBitLength,
byte *recoveredMessage) const
{throw NotImplemented("PK_MessageEncodingMethod: this signature scheme does not support message recovery");}
virtual DecodingResult RecoverMessageFromSemisignature( // for DL
HashTransformation &hash, HashIdentifier hashIdentifier,
const byte *presignature, size_t presignatureLength,
const byte *semisignature, size_t semisignatureLength,
byte *recoveredMessage) const
{throw NotImplemented("PK_MessageEncodingMethod: this signature scheme does not support message recovery");}
// VC60 workaround
struct HashIdentifierLookup
{
template <class H> struct HashIdentifierLookup2
{
static HashIdentifier CRYPTOPP_API Lookup()
{
return HashIdentifier(NULL, 0);
}
};
};
};
class CRYPTOPP_DLL CRYPTOPP_NO_VTABLE PK_DeterministicSignatureMessageEncodingMethod : public PK_SignatureMessageEncodingMethod
{
public:
bool VerifyMessageRepresentative(
HashTransformation &hash, HashIdentifier hashIdentifier, bool messageEmpty,
byte *representative, size_t representativeBitLength) const;
};
class CRYPTOPP_DLL CRYPTOPP_NO_VTABLE PK_RecoverableSignatureMessageEncodingMethod : public PK_SignatureMessageEncodingMethod
{
public:
bool VerifyMessageRepresentative(
HashTransformation &hash, HashIdentifier hashIdentifier, bool messageEmpty,
byte *representative, size_t representativeBitLength) const;
};
class CRYPTOPP_DLL DL_SignatureMessageEncodingMethod_DSA : public PK_DeterministicSignatureMessageEncodingMethod
{
public:
void ComputeMessageRepresentative(RandomNumberGenerator &rng,
const byte *recoverableMessage, size_t recoverableMessageLength,
HashTransformation &hash, HashIdentifier hashIdentifier, bool messageEmpty,
byte *representative, size_t representativeBitLength) const;
};
class CRYPTOPP_DLL DL_SignatureMessageEncodingMethod_NR : public PK_DeterministicSignatureMessageEncodingMethod
{
public:
void ComputeMessageRepresentative(RandomNumberGenerator &rng,
const byte *recoverableMessage, size_t recoverableMessageLength,
HashTransformation &hash, HashIdentifier hashIdentifier, bool messageEmpty,
byte *representative, size_t representativeBitLength) const;
};
class CRYPTOPP_DLL CRYPTOPP_NO_VTABLE PK_MessageAccumulatorBase : public PK_MessageAccumulator
{
public:
PK_MessageAccumulatorBase() : m_empty(true) {}
virtual HashTransformation & AccessHash() =0;
void Update(const byte *input, size_t length)
{
AccessHash().Update(input, length);
m_empty = m_empty && length == 0;
}
SecByteBlock m_recoverableMessage, m_representative, m_presignature, m_semisignature;
Integer m_k, m_s;
bool m_empty;
};
template <class HASH_ALGORITHM>
class PK_MessageAccumulatorImpl : public PK_MessageAccumulatorBase, protected ObjectHolder<HASH_ALGORITHM>
{
public:
HashTransformation & AccessHash() {return this->m_object;}
};
//! _
template <class INTERFACE, class BASE>
class CRYPTOPP_NO_VTABLE TF_SignatureSchemeBase : public INTERFACE, protected BASE
{
public:
size_t SignatureLength() const
{return this->GetTrapdoorFunctionBounds().MaxPreimage().ByteCount();}
size_t MaxRecoverableLength() const
{return this->GetMessageEncodingInterface().MaxRecoverableLength(MessageRepresentativeBitLength(), GetHashIdentifier().second, GetDigestSize());}
size_t MaxRecoverableLengthFromSignatureLength(size_t signatureLength) const
{return this->MaxRecoverableLength();}
bool IsProbabilistic() const
{return this->GetTrapdoorFunctionInterface().IsRandomized() || this->GetMessageEncodingInterface().IsProbabilistic();}
bool AllowNonrecoverablePart() const
{return this->GetMessageEncodingInterface().AllowNonrecoverablePart();}
bool RecoverablePartFirst() const
{return this->GetMessageEncodingInterface().RecoverablePartFirst();}
protected:
size_t MessageRepresentativeLength() const {return BitsToBytes(MessageRepresentativeBitLength());}
size_t MessageRepresentativeBitLength() const {return this->GetTrapdoorFunctionBounds().ImageBound().BitCount()-1;}
virtual HashIdentifier GetHashIdentifier() const =0;
virtual size_t GetDigestSize() const =0;
};
//! _
class CRYPTOPP_DLL CRYPTOPP_NO_VTABLE TF_SignerBase : public TF_SignatureSchemeBase<PK_Signer, TF_Base<RandomizedTrapdoorFunctionInverse, PK_SignatureMessageEncodingMethod> >
{
public:
void InputRecoverableMessage(PK_MessageAccumulator &messageAccumulator, const byte *recoverableMessage, size_t recoverableMessageLength) const;
size_t SignAndRestart(RandomNumberGenerator &rng, PK_MessageAccumulator &messageAccumulator, byte *signature, bool restart=true) const;
};
//! _
class CRYPTOPP_DLL CRYPTOPP_NO_VTABLE TF_VerifierBase : public TF_SignatureSchemeBase<PK_Verifier, TF_Base<TrapdoorFunction, PK_SignatureMessageEncodingMethod> >
{
public:
void InputSignature(PK_MessageAccumulator &messageAccumulator, const byte *signature, size_t signatureLength) const;
bool VerifyAndRestart(PK_MessageAccumulator &messageAccumulator) const;
DecodingResult RecoverAndRestart(byte *recoveredMessage, PK_MessageAccumulator &recoveryAccumulator) const;
};
// ********************************************************
//! _
template <class T1, class T2, class T3>
struct TF_CryptoSchemeOptions
{
typedef T1 AlgorithmInfo;
typedef T2 Keys;
typedef typename Keys::PrivateKey PrivateKey;
typedef typename Keys::PublicKey PublicKey;
typedef T3 MessageEncodingMethod;
};
//! _
template <class T1, class T2, class T3, class T4>
struct TF_SignatureSchemeOptions : public TF_CryptoSchemeOptions<T1, T2, T3>
{
typedef T4 HashFunction;
};
//! _
template <class BASE, class SCHEME_OPTIONS, class KEY_CLASS>
class CRYPTOPP_NO_VTABLE TF_ObjectImplBase : public AlgorithmImpl<BASE, typename SCHEME_OPTIONS::AlgorithmInfo>
{
public:
typedef SCHEME_OPTIONS SchemeOptions;
typedef KEY_CLASS KeyClass;
PublicKey & AccessPublicKey() {return AccessKey();}
const PublicKey & GetPublicKey() const {return GetKey();}
PrivateKey & AccessPrivateKey() {return AccessKey();}
const PrivateKey & GetPrivateKey() const {return GetKey();}
virtual const KeyClass & GetKey() const =0;
virtual KeyClass & AccessKey() =0;
const KeyClass & GetTrapdoorFunction() const {return GetKey();}
PK_MessageAccumulator * NewSignatureAccumulator(RandomNumberGenerator &rng) const
{
return new PK_MessageAccumulatorImpl<CPP_TYPENAME SCHEME_OPTIONS::HashFunction>;
}
PK_MessageAccumulator * NewVerificationAccumulator() const
{
return new PK_MessageAccumulatorImpl<CPP_TYPENAME SCHEME_OPTIONS::HashFunction>;
}
protected:
const typename BASE::MessageEncodingInterface & GetMessageEncodingInterface() const
{return Singleton<CPP_TYPENAME SCHEME_OPTIONS::MessageEncodingMethod>().Ref();}
const TrapdoorFunctionBounds & GetTrapdoorFunctionBounds() const
{return GetKey();}
const typename BASE::TrapdoorFunctionInterface & GetTrapdoorFunctionInterface() const
{return GetKey();}
// for signature scheme
HashIdentifier GetHashIdentifier() const
{
typedef CPP_TYPENAME SchemeOptions::MessageEncodingMethod::HashIdentifierLookup::template HashIdentifierLookup2<CPP_TYPENAME SchemeOptions::HashFunction> L;
return L::Lookup();
}
size_t GetDigestSize() const
{
typedef CPP_TYPENAME SchemeOptions::HashFunction H;
return H::DIGESTSIZE;
}
};
//! _
template <class BASE, class SCHEME_OPTIONS, class KEY>
class TF_ObjectImplExtRef : public TF_ObjectImplBase<BASE, SCHEME_OPTIONS, KEY>
{
public:
TF_ObjectImplExtRef(const KEY *pKey = NULL) : m_pKey(pKey) {}
void SetKeyPtr(const KEY *pKey) {m_pKey = pKey;}
const KEY & GetKey() const {return *m_pKey;}
KEY & AccessKey() {throw NotImplemented("TF_ObjectImplExtRef: cannot modify refererenced key");}
private:
const KEY * m_pKey;
};
//! _
template <class BASE, class SCHEME_OPTIONS, class KEY_CLASS>
class CRYPTOPP_NO_VTABLE TF_ObjectImpl : public TF_ObjectImplBase<BASE, SCHEME_OPTIONS, KEY_CLASS>
{
public:
typedef KEY_CLASS KeyClass;
const KeyClass & GetKey() const {return m_trapdoorFunction;}
KeyClass & AccessKey() {return m_trapdoorFunction;}
private:
KeyClass m_trapdoorFunction;
};
//! _
template <class SCHEME_OPTIONS>
class TF_DecryptorImpl : public TF_ObjectImpl<TF_DecryptorBase, SCHEME_OPTIONS, typename SCHEME_OPTIONS::PrivateKey>
{
};
//! _
template <class SCHEME_OPTIONS>
class TF_EncryptorImpl : public TF_ObjectImpl<TF_EncryptorBase, SCHEME_OPTIONS, typename SCHEME_OPTIONS::PublicKey>
{
};
//! _
template <class SCHEME_OPTIONS>
class TF_SignerImpl : public TF_ObjectImpl<TF_SignerBase, SCHEME_OPTIONS, typename SCHEME_OPTIONS::PrivateKey>
{
};
//! _
template <class SCHEME_OPTIONS>
class TF_VerifierImpl : public TF_ObjectImpl<TF_VerifierBase, SCHEME_OPTIONS, typename SCHEME_OPTIONS::PublicKey>
{
};
// ********************************************************
//! _
class CRYPTOPP_NO_VTABLE MaskGeneratingFunction
{
public:
virtual ~MaskGeneratingFunction() {}
virtual void GenerateAndMask(HashTransformation &hash, byte *output, size_t outputLength, const byte *input, size_t inputLength, bool mask = true) const =0;
};
CRYPTOPP_DLL void CRYPTOPP_API 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);
//! _
class P1363_MGF1 : public MaskGeneratingFunction
{
public:
static const char * CRYPTOPP_API StaticAlgorithmName() {return "MGF1";}
void GenerateAndMask(HashTransformation &hash, byte *output, size_t outputLength, const byte *input, size_t inputLength, bool mask = true) const
{
P1363_MGF1KDF2_Common(hash, output, outputLength, input, inputLength, NULL, 0, mask, 0);
}
};
// ********************************************************
//! _
template <class H>
class P1363_KDF2
{
public:
static void CRYPTOPP_API DeriveKey(byte *output, size_t outputLength, const byte *input, size_t inputLength, const byte *derivationParams, size_t derivationParamsLength)
{
H h;
P1363_MGF1KDF2_Common(h, output, outputLength, input, inputLength, derivationParams, derivationParamsLength, false, 1);
}
};
// ********************************************************
//! to be thrown by DecodeElement and AgreeWithStaticPrivateKey
class DL_BadElement : public InvalidDataFormat
{
public:
DL_BadElement() : InvalidDataFormat("CryptoPP: invalid group element") {}
};
//! interface for DL group parameters
template <class T>
class CRYPTOPP_NO_VTABLE DL_GroupParameters : public CryptoParameters
{
typedef DL_GroupParameters<T> ThisClass;
public:
typedef T Element;
DL_GroupParameters() : m_validationLevel(0) {}
// CryptoMaterial
bool Validate(RandomNumberGenerator &rng, unsigned int level) const
{
if (!GetBasePrecomputation().IsInitialized())
return false;
if (m_validationLevel > level)
return true;
bool pass = ValidateGroup(rng, level);
pass = pass && ValidateElement(level, GetSubgroupGenerator(), &GetBasePrecomputation());
m_validationLevel = pass ? level+1 : 0;
return pass;
}
bool GetVoidValue(const char *name, const std::type_info &valueType, void *pValue) const
{
return GetValueHelper(this, name, valueType, pValue)
CRYPTOPP_GET_FUNCTION_ENTRY(SubgroupOrder)
CRYPTOPP_GET_FUNCTION_ENTRY(SubgroupGenerator)
;
}
bool SupportsPrecomputation() const {return true;}
void Precompute(unsigned int precomputationStorage=16)
{
AccessBasePrecomputation().Precompute(GetGroupPrecomputation(), GetSubgroupOrder().BitCount(), precomputationStorage);
}
void LoadPrecomputation(BufferedTransformation &storedPrecomputation)
{
AccessBasePrecomputation().Load(GetGroupPrecomputation(), storedPrecomputation);
m_validationLevel = 0;
}
void SavePrecomputation(BufferedTransformation &storedPrecomputation) const
{
GetBasePrecomputation().Save(GetGroupPrecomputation(), storedPrecomputation);
}
// non-inherited
virtual const Element & GetSubgroupGenerator() const {return GetBasePrecomputation().GetBase(GetGroupPrecomputation());}
virtual void SetSubgroupGenerator(const Element &base) {AccessBasePrecomputation().SetBase(GetGroupPrecomputation(), base);}
virtual Element ExponentiateBase(const Integer &exponent) const
{
return GetBasePrecomputation().Exponentiate(GetGroupPrecomputation(), exponent);
}
virtual Element ExponentiateElement(const Element &base, const Integer &exponent) const
{
Element result;
SimultaneousExponentiate(&result, base, &exponent, 1);
return result;
}
virtual const DL_GroupPrecomputation<Element> & GetGroupPrecomputation() const =0;
virtual const DL_FixedBasePrecomputation<Element> & GetBasePrecomputation() const =0;
virtual DL_FixedBasePrecomputation<Element> & AccessBasePrecomputation() =0;
virtual const Integer & GetSubgroupOrder() const =0; // order of subgroup generated by base element
virtual Integer GetMaxExponent() const =0;
virtual Integer GetGroupOrder() const {return GetSubgroupOrder()*GetCofactor();} // one of these two needs to be overriden
virtual Integer GetCofactor() const {return GetGroupOrder()/GetSubgroupOrder();}
virtual unsigned int GetEncodedElementSize(bool reversible) const =0;
virtual void EncodeElement(bool reversible, const Element &element, byte *encoded) const =0;
virtual Element DecodeElement(const byte *encoded, bool checkForGroupMembership) const =0;
virtual Integer ConvertElementToInteger(const Element &element) const =0;
virtual bool ValidateGroup(RandomNumberGenerator &rng, unsigned int level) const =0;
virtual bool ValidateElement(unsigned int level, const Element &element, const DL_FixedBasePrecomputation<Element> *precomp) const =0;
virtual bool FastSubgroupCheckAvailable() const =0;
virtual bool IsIdentity(const Element &element) const =0;
virtual void SimultaneousExponentiate(Element *results, const Element &base, const Integer *exponents, unsigned int exponentsCount) const =0;
protected:
void ParametersChanged() {m_validationLevel = 0;}
private:
mutable unsigned int m_validationLevel;
};
//! _
template <class GROUP_PRECOMP, class BASE_PRECOMP = DL_FixedBasePrecomputationImpl<CPP_TYPENAME GROUP_PRECOMP::Element>, class BASE = DL_GroupParameters<CPP_TYPENAME GROUP_PRECOMP::Element> >
class DL_GroupParametersImpl : public BASE
{
public:
typedef GROUP_PRECOMP GroupPrecomputation;
typedef typename GROUP_PRECOMP::Element Element;
typedef BASE_PRECOMP BasePrecomputation;
const DL_GroupPrecomputation<Element> & GetGroupPrecomputation() const {return m_groupPrecomputation;}
const DL_FixedBasePrecomputation<Element> & GetBasePrecomputation() const {return m_gpc;}
DL_FixedBasePrecomputation<Element> & AccessBasePrecomputation() {return m_gpc;}
protected:
GROUP_PRECOMP m_groupPrecomputation;
BASE_PRECOMP m_gpc;
};
//! _
template <class T>
class CRYPTOPP_NO_VTABLE DL_Key
{
public:
virtual const DL_GroupParameters<T> & GetAbstractGroupParameters() const =0;
virtual DL_GroupParameters<T> & AccessAbstractGroupParameters() =0;
};
//! interface for DL public keys
template <class T>
class CRYPTOPP_NO_VTABLE DL_PublicKey : public DL_Key<T>
{
typedef DL_PublicKey<T> ThisClass;
public:
typedef T Element;
bool GetVoidValue(const char *name, const std::type_info &valueType, void *pValue) const
{
return GetValueHelper(this, name, valueType, pValue, &this->GetAbstractGroupParameters())
CRYPTOPP_GET_FUNCTION_ENTRY(PublicElement);
}
void AssignFrom(const NameValuePairs &source);
// non-inherited
virtual const Element & GetPublicElement() const {return GetPublicPrecomputation().GetBase(this->GetAbstractGroupParameters().GetGroupPrecomputation());}
virtual void SetPublicElement(const Element &y) {AccessPublicPrecomputation().SetBase(this->GetAbstractGroupParameters().GetGroupPrecomputation(), y);}
virtual Element ExponentiatePublicElement(const Integer &exponent) const
{
const DL_GroupParameters<T> ¶ms = this->GetAbstractGroupParameters();
return GetPublicPrecomputation().Exponentiate(params.GetGroupPrecomputation(), exponent);
}
virtual Element CascadeExponentiateBaseAndPublicElement(const Integer &baseExp, const Integer &publicExp) const
{
const DL_GroupParameters<T> ¶ms = this->GetAbstractGroupParameters();
return params.GetBasePrecomputation().CascadeExponentiate(params.GetGroupPrecomputation(), baseExp, GetPublicPrecomputation(), publicExp);
}
virtual const DL_FixedBasePrecomputation<T> & GetPublicPrecomputation() const =0;
virtual DL_FixedBasePrecomputation<T> & AccessPublicPrecomputation() =0;
};
//! interface for DL private keys
template <class T>
class CRYPTOPP_NO_VTABLE DL_PrivateKey : public DL_Key<T>
{
typedef DL_PrivateKey<T> ThisClass;
public:
typedef T Element;
void MakePublicKey(DL_PublicKey<T> &pub) const
{
pub.AccessAbstractGroupParameters().AssignFrom(this->GetAbstractGroupParameters());
pub.SetPublicElement(this->GetAbstractGroupParameters().ExponentiateBase(GetPrivateExponent()));
}
bool GetVoidValue(const char *name, const std::type_info &valueType, void *pValue) const
{
return GetValueHelper(this, name, valueType, pValue, &this->GetAbstractGroupParameters())
CRYPTOPP_GET_FUNCTION_ENTRY(PrivateExponent);
}
void AssignFrom(const NameValuePairs &source)
{
this->AccessAbstractGroupParameters().AssignFrom(source);
AssignFromHelper(this, source)
CRYPTOPP_SET_FUNCTION_ENTRY(PrivateExponent);
}
virtual const Integer & GetPrivateExponent() const =0;
virtual void SetPrivateExponent(const Integer &x) =0;
};
template <class T>
void DL_PublicKey<T>::AssignFrom(const NameValuePairs &source)
{
DL_PrivateKey<T> *pPrivateKey = NULL;
if (source.GetThisPointer(pPrivateKey))
pPrivateKey->MakePublicKey(*this);
else
{
this->AccessAbstractGroupParameters().AssignFrom(source);
AssignFromHelper(this, source)
CRYPTOPP_SET_FUNCTION_ENTRY(PublicElement);
}
}
class OID;
//! _
template <class PK, class GP, class O = OID>
class DL_KeyImpl : public PK
{
public:
typedef GP GroupParameters;
O GetAlgorithmID() const {return GetGroupParameters().GetAlgorithmID();}
// void BERDecode(BufferedTransformation &bt)
// {PK::BERDecode(bt);}
// void DEREncode(BufferedTransformation &bt) const
// {PK::DEREncode(bt);}
bool BERDecodeAlgorithmParameters(BufferedTransformation &bt)
{AccessGroupParameters().BERDecode(bt); return true;}
bool DEREncodeAlgorithmParameters(BufferedTransformation &bt) const
{GetGroupParameters().DEREncode(bt); return true;}
const GP & GetGroupParameters() const {return m_groupParameters;}
GP & AccessGroupParameters() {return m_groupParameters;}
private:
GP m_groupParameters;
};
class X509PublicKey;
class PKCS8PrivateKey;
//! _
template <class GP>
class DL_PrivateKeyImpl : public DL_PrivateKey<CPP_TYPENAME GP::Element>, public DL_KeyImpl<PKCS8PrivateKey, GP>
{
public:
typedef typename GP::Element Element;
// GeneratableCryptoMaterial
bool Validate(RandomNumberGenerator &rng, unsigned int level) const
{
bool pass = GetAbstractGroupParameters().Validate(rng, level);
const Integer &q = GetAbstractGroupParameters().GetSubgroupOrder();
const Integer &x = GetPrivateExponent();
pass = pass && x.IsPositive() && x < q;
if (level >= 1)
pass = pass && Integer::Gcd(x, q) == Integer::One();
return pass;
}
bool GetVoidValue(const char *name, const std::type_info &valueType, void *pValue) const
{
return GetValueHelper<DL_PrivateKey<Element> >(this, name, valueType, pValue).Assignable();
}
void AssignFrom(const NameValuePairs &source)
{
AssignFromHelper<DL_PrivateKey<Element> >(this, source);
}
void GenerateRandom(RandomNumberGenerator &rng, const NameValuePairs ¶ms)
{
if (!params.GetThisObject(this->AccessGroupParameters()))
this->AccessGroupParameters().GenerateRandom(rng, params);
// std::pair<const byte *, int> seed;
Integer x(rng, Integer::One(), GetAbstractGroupParameters().GetMaxExponent());
// Integer::ANY, Integer::Zero(), Integer::One(),
// params.GetValue("DeterministicKeyGenerationSeed", seed) ? &seed : NULL);
SetPrivateExponent(x);
}
bool SupportsPrecomputation() const {return true;}
void Precompute(unsigned int precomputationStorage=16)
{AccessAbstractGroupParameters().Precompute(precomputationStorage);}
void LoadPrecomputation(BufferedTransformation &storedPrecomputation)
{AccessAbstractGroupParameters().LoadPrecomputation(storedPrecomputation);}
void SavePrecomputation(BufferedTransformation &storedPrecomputation) const
{GetAbstractGroupParameters().SavePrecomputation(storedPrecomputation);}
// DL_Key
const DL_GroupParameters<Element> & GetAbstractGroupParameters() const {return this->GetGroupParameters();}
DL_GroupParameters<Element> & AccessAbstractGroupParameters() {return this->AccessGroupParameters();}
// DL_PrivateKey
const Integer & GetPrivateExponent() const {return m_x;}
void SetPrivateExponent(const Integer &x) {m_x = x;}
// PKCS8PrivateKey
void BERDecodePrivateKey(BufferedTransformation &bt, bool, size_t)
{m_x.BERDecode(bt);}
void DEREncodePrivateKey(BufferedTransformation &bt) const
{m_x.DEREncode(bt);}
private:
Integer m_x;
};
//! _
template <class BASE, class SIGNATURE_SCHEME>
class DL_PrivateKey_WithSignaturePairwiseConsistencyTest : public BASE
{
public:
void GenerateRandom(RandomNumberGenerator &rng, const NameValuePairs ¶ms)
{
BASE::GenerateRandom(rng, params);
if (FIPS_140_2_ComplianceEnabled())
{
typename SIGNATURE_SCHEME::Signer signer(*this);
typename SIGNATURE_SCHEME::Verifier verifier(signer);
SignaturePairwiseConsistencyTest_FIPS_140_Only(signer, verifier);
}
}
};
//! _
template <class GP>
class DL_PublicKeyImpl : public DL_PublicKey<typename GP::Element>, public DL_KeyImpl<X509PublicKey, GP>
{
public:
typedef typename GP::Element Element;
// CryptoMaterial
bool Validate(RandomNumberGenerator &rng, unsigned int level) const
{
bool pass = GetAbstractGroupParameters().Validate(rng, level);
pass = pass && GetAbstractGroupParameters().ValidateElement(level, this->GetPublicElement(), &GetPublicPrecomputation());
return pass;
}
bool GetVoidValue(const char *name, const std::type_info &valueType, void *pValue) const
{
return GetValueHelper<DL_PublicKey<Element> >(this, name, valueType, pValue).Assignable();
}
void AssignFrom(const NameValuePairs &source)
{
AssignFromHelper<DL_PublicKey<Element> >(this, source);
}
bool SupportsPrecomputation() const {return true;}
void Precompute(unsigned int precomputationStorage=16)
{
AccessAbstractGroupParameters().Precompute(precomputationStorage);
AccessPublicPrecomputation().Precompute(GetAbstractGroupParameters().GetGroupPrecomputation(), GetAbstractGroupParameters().GetSubgroupOrder().BitCount(), precomputationStorage);
}
void LoadPrecomputation(BufferedTransformation &storedPrecomputation)
{
AccessAbstractGroupParameters().LoadPrecomputation(storedPrecomputation);
AccessPublicPrecomputation().Load(GetAbstractGroupParameters().GetGroupPrecomputation(), storedPrecomputation);
}
void SavePrecomputation(BufferedTransformation &storedPrecomputation) const
{
GetAbstractGroupParameters().SavePrecomputation(storedPrecomputation);
GetPublicPrecomputation().Save(GetAbstractGroupParameters().GetGroupPrecomputation(), storedPrecomputation);
}
// DL_Key
const DL_GroupParameters<Element> & GetAbstractGroupParameters() const {return this->GetGroupParameters();}
DL_GroupParameters<Element> & AccessAbstractGroupParameters() {return this->AccessGroupParameters();}
// DL_PublicKey
const DL_FixedBasePrecomputation<Element> & GetPublicPrecomputation() const {return m_ypc;}
DL_FixedBasePrecomputation<Element> & AccessPublicPrecomputation() {return m_ypc;}
// non-inherited
bool operator==(const DL_PublicKeyImpl<GP> &rhs) const
{return this->GetGroupParameters() == rhs.GetGroupParameters() && this->GetPublicElement() == rhs.GetPublicElement();}
private:
typename GP::BasePrecomputation m_ypc;
};
//! interface for Elgamal-like signature algorithms
template <class T>
class CRYPTOPP_NO_VTABLE DL_ElgamalLikeSignatureAlgorithm
{
public:
virtual void Sign(const DL_GroupParameters<T> ¶ms, const Integer &privateKey, const Integer &k, const Integer &e, Integer &r, Integer &s) const =0;
virtual bool Verify(const DL_GroupParameters<T> ¶ms, const DL_PublicKey<T> &publicKey, const Integer &e, const Integer &r, const Integer &s) const =0;
virtual Integer RecoverPresignature(const DL_GroupParameters<T> ¶ms, const DL_PublicKey<T> &publicKey, const Integer &r, const Integer &s) const
{throw NotImplemented("DL_ElgamalLikeSignatureAlgorithm: this signature scheme does not support message recovery");}
virtual size_t RLen(const DL_GroupParameters<T> ¶ms) const
{return params.GetSubgroupOrder().ByteCount();}
virtual size_t SLen(const DL_GroupParameters<T> ¶ms) const
{return params.GetSubgroupOrder().ByteCount();}
};
//! interface for DL key agreement algorithms
template <class T>
class CRYPTOPP_NO_VTABLE DL_KeyAgreementAlgorithm
{
public:
typedef T Element;
virtual Element AgreeWithEphemeralPrivateKey(const DL_GroupParameters<Element> ¶ms, const DL_FixedBasePrecomputation<Element> &publicPrecomputation, const Integer &privateExponent) const =0;
virtual Element AgreeWithStaticPrivateKey(const DL_GroupParameters<Element> ¶ms, const Element &publicElement, bool validateOtherPublicKey, const Integer &privateExponent) const =0;
};
//! interface for key derivation algorithms used in DL cryptosystems
template <class T>
class CRYPTOPP_NO_VTABLE DL_KeyDerivationAlgorithm
{
public:
virtual bool ParameterSupported(const char *name) const {return false;}
virtual void Derive(const DL_GroupParameters<T> &groupParams, byte *derivedKey, size_t derivedLength, const T &agreedElement, const T &ephemeralPublicKey, const NameValuePairs &derivationParams) const =0;
};
//! interface for symmetric encryption algorithms used in DL cryptosystems
class CRYPTOPP_NO_VTABLE DL_SymmetricEncryptionAlgorithm
{
public:
virtual bool ParameterSupported(const char *name) const {return false;}
virtual size_t GetSymmetricKeyLength(size_t plaintextLength) const =0;
virtual size_t GetSymmetricCiphertextLength(size_t plaintextLength) const =0;
virtual size_t GetMaxSymmetricPlaintextLength(size_t ciphertextLength) const =0;
virtual void SymmetricEncrypt(RandomNumberGenerator &rng, const byte *key, const byte *plaintext, size_t plaintextLength, byte *ciphertext, const NameValuePairs ¶meters) const =0;
virtual DecodingResult SymmetricDecrypt(const byte *key, const byte *ciphertext, size_t ciphertextLength, byte *plaintext, const NameValuePairs ¶meters) const =0;
};
//! _
template <class KI>
class CRYPTOPP_NO_VTABLE DL_Base
{
protected:
typedef KI KeyInterface;
typedef typename KI::Element Element;
const DL_GroupParameters<Element> & GetAbstractGroupParameters() const {return GetKeyInterface().GetAbstractGroupParameters();}
DL_GroupParameters<Element> & AccessAbstractGroupParameters() {return AccessKeyInterface().AccessAbstractGroupParameters();}
virtual KeyInterface & AccessKeyInterface() =0;
virtual const KeyInterface & GetKeyInterface() const =0;
};
//! _
template <class INTERFACE, class KEY_INTERFACE>
class CRYPTOPP_NO_VTABLE DL_SignatureSchemeBase : public INTERFACE, public DL_Base<KEY_INTERFACE>
{
public:
size_t SignatureLength() const
{
return GetSignatureAlgorithm().RLen(this->GetAbstractGroupParameters())
+ GetSignatureAlgorithm().SLen(this->GetAbstractGroupParameters());
}
size_t MaxRecoverableLength() const
{return GetMessageEncodingInterface().MaxRecoverableLength(0, GetHashIdentifier().second, GetDigestSize());}
size_t MaxRecoverableLengthFromSignatureLength(size_t signatureLength) const
{assert(false); return 0;} // TODO
bool IsProbabilistic() const
{return true;}
bool AllowNonrecoverablePart() const
{return GetMessageEncodingInterface().AllowNonrecoverablePart();}
bool RecoverablePartFirst() const
{return GetMessageEncodingInterface().RecoverablePartFirst();}
protected:
size_t MessageRepresentativeLength() const {return BitsToBytes(MessageRepresentativeBitLength());}
size_t MessageRepresentativeBitLength() const {return this->GetAbstractGroupParameters().GetSubgroupOrder().BitCount();}
virtual const DL_ElgamalLikeSignatureAlgorithm<CPP_TYPENAME KEY_INTERFACE::Element> & GetSignatureAlgorithm() const =0;
virtual const PK_SignatureMessageEncodingMethod & GetMessageEncodingInterface() const =0;
virtual HashIdentifier GetHashIdentifier() const =0;
virtual size_t GetDigestSize() const =0;
};
//! _
template <class T>
class CRYPTOPP_NO_VTABLE DL_SignerBase : public DL_SignatureSchemeBase<PK_Signer, DL_PrivateKey<T> >
{
public:
// for validation testing
void RawSign(const Integer &k, const Integer &e, Integer &r, Integer &s) const
{
const DL_ElgamalLikeSignatureAlgorithm<T> &alg = this->GetSignatureAlgorithm();
const DL_GroupParameters<T> ¶ms = this->GetAbstractGroupParameters();
const DL_PrivateKey<T> &key = this->GetKeyInterface();
r = params.ConvertElementToInteger(params.ExponentiateBase(k));
alg.Sign(params, key.GetPrivateExponent(), k, e, r, s);
}
void InputRecoverableMessage(PK_MessageAccumulator &messageAccumulator, const byte *recoverableMessage, size_t recoverableMessageLength) const
{
PK_MessageAccumulatorBase &ma = static_cast<PK_MessageAccumulatorBase &>(messageAccumulator);
ma.m_recoverableMessage.Assign(recoverableMessage, recoverableMessageLength);
this->GetMessageEncodingInterface().ProcessRecoverableMessage(ma.AccessHash(),
recoverableMessage, recoverableMessageLength,
ma.m_presignature, ma.m_presignature.size(),
ma.m_semisignature);
}
size_t SignAndRestart(RandomNumberGenerator &rng, PK_MessageAccumulator &messageAccumulator, byte *signature, bool restart) const
{
this->GetMaterial().DoQuickSanityCheck();
PK_MessageAccumulatorBase &ma = static_cast<PK_MessageAccumulatorBase &>(messageAccumulator);
const DL_ElgamalLikeSignatureAlgorithm<T> &alg = this->GetSignatureAlgorithm();
const DL_GroupParameters<T> ¶ms = this->GetAbstractGroupParameters();
const DL_PrivateKey<T> &key = this->GetKeyInterface();
SecByteBlock representative(this->MessageRepresentativeLength());
this->GetMessageEncodingInterface().ComputeMessageRepresentative(
rng,
ma.m_recoverableMessage, ma.m_recoverableMessage.size(),
ma.AccessHash(), this->GetHashIdentifier(), ma.m_empty,
representative, this->MessageRepresentativeBitLength());
ma.m_empty = true;
Integer e(representative, representative.size());
Integer r;
if (this->MaxRecoverableLength() > 0)
r.Decode(ma.m_semisignature, ma.m_semisignature.size());
else
r.Decode(ma.m_presignature, ma.m_presignature.size());
Integer s;
alg.Sign(params, key.GetPrivateExponent(), ma.m_k, e, r, s);
size_t rLen = alg.RLen(params);
r.Encode(signature, rLen);
s.Encode(signature+rLen, alg.SLen(params));
if (restart)
RestartMessageAccumulator(rng, ma);
return this->SignatureLength();
}
protected:
void RestartMessageAccumulator(RandomNumberGenerator &rng, PK_MessageAccumulatorBase &ma) const
{
const DL_ElgamalLikeSignatureAlgorithm<T> &alg = this->GetSignatureAlgorithm();
const DL_GroupParameters<T> ¶ms = this->GetAbstractGroupParameters();
ma.m_k.Randomize(rng, 1, params.GetSubgroupOrder()-1);
ma.m_presignature.New(params.GetEncodedElementSize(false));
params.ConvertElementToInteger(params.ExponentiateBase(ma.m_k)).Encode(ma.m_presignature, ma.m_presignature.size());
}
};
//! _
template <class T>
class CRYPTOPP_NO_VTABLE DL_VerifierBase : public DL_SignatureSchemeBase<PK_Verifier, DL_PublicKey<T> >
{
public:
void InputSignature(PK_MessageAccumulator &messageAccumulator, const byte *signature, size_t signatureLength) const
{
PK_MessageAccumulatorBase &ma = static_cast<PK_MessageAccumulatorBase &>(messageAccumulator);
const DL_ElgamalLikeSignatureAlgorithm<T> &alg = this->GetSignatureAlgorithm();
const DL_GroupParameters<T> ¶ms = this->GetAbstractGroupParameters();
size_t rLen = alg.RLen(params);
ma.m_semisignature.Assign(signature, rLen);
ma.m_s.Decode(signature+rLen, alg.SLen(params));
this->GetMessageEncodingInterface().ProcessSemisignature(ma.AccessHash(), ma.m_semisignature, ma.m_semisignature.size());
}
bool VerifyAndRestart(PK_MessageAccumulator &messageAccumulator) const
{
this->GetMaterial().DoQuickSanityCheck();
PK_MessageAccumulatorBase &ma = static_cast<PK_MessageAccumulatorBase &>(messageAccumulator);
const DL_ElgamalLikeSignatureAlgorithm<T> &alg = this->GetSignatureAlgorithm();
const DL_GroupParameters<T> ¶ms = this->GetAbstractGroupParameters();
const DL_PublicKey<T> &key = this->GetKeyInterface();
SecByteBlock representative(this->MessageRepresentativeLength());
this->GetMessageEncodingInterface().ComputeMessageRepresentative(NullRNG(), ma.m_recoverableMessage, ma.m_recoverableMessage.size(),
ma.AccessHash(), this->GetHashIdentifier(), ma.m_empty,
representative, this->MessageRepresentativeBitLength());
ma.m_empty = true;
Integer e(representative, representative.size());
Integer r(ma.m_semisignature, ma.m_semisignature.size());
return alg.Verify(params, key, e, r, ma.m_s);
}
DecodingResult RecoverAndRestart(byte *recoveredMessage, PK_MessageAccumulator &messageAccumulator) const
{
this->GetMaterial().DoQuickSanityCheck();
PK_MessageAccumulatorBase &ma = static_cast<PK_MessageAccumulatorBase &>(messageAccumulator);
const DL_ElgamalLikeSignatureAlgorithm<T> &alg = this->GetSignatureAlgorithm();
const DL_GroupParameters<T> ¶ms = this->GetAbstractGroupParameters();
const DL_PublicKey<T> &key = this->GetKeyInterface();
SecByteBlock representative(this->MessageRepresentativeLength());
this->GetMessageEncodingInterface().ComputeMessageRepresentative(
NullRNG(),
ma.m_recoverableMessage, ma.m_recoverableMessage.size(),
ma.AccessHash(), this->GetHashIdentifier(), ma.m_empty,
representative, this->MessageRepresentativeBitLength());
ma.m_empty = true;
Integer e(representative, representative.size());
ma.m_presignature.New(params.GetEncodedElementSize(false));
Integer r(ma.m_semisignature, ma.m_semisignature.size());
alg.RecoverPresignature(params, key, r, ma.m_s).Encode(ma.m_presignature, ma.m_presignature.size());
return this->GetMessageEncodingInterface().RecoverMessageFromSemisignature(
ma.AccessHash(), this->GetHashIdentifier(),
ma.m_presignature, ma.m_presignature.size(),
ma.m_semisignature, ma.m_semisignature.size(),
recoveredMessage);
}
};
//! _
template <class PK, class KI>
class CRYPTOPP_NO_VTABLE DL_CryptoSystemBase : public PK, public DL_Base<KI>
{
public:
typedef typename DL_Base<KI>::Element Element;
size_t MaxPlaintextLength(size_t ciphertextLength) const
{
unsigned int minLen = this->GetAbstractGroupParameters().GetEncodedElementSize(true);
return ciphertextLength < minLen ? 0 : GetSymmetricEncryptionAlgorithm().GetMaxSymmetricPlaintextLength(ciphertextLength - minLen);
}
size_t CiphertextLength(size_t plaintextLength) const
{
size_t len = GetSymmetricEncryptionAlgorithm().GetSymmetricCiphertextLength(plaintextLength);
return len == 0 ? 0 : this->GetAbstractGroupParameters().GetEncodedElementSize(true) + len;
}
bool ParameterSupported(const char *name) const
{return GetKeyDerivationAlgorithm().ParameterSupported(name) || GetSymmetricEncryptionAlgorithm().ParameterSupported(name);}
protected:
virtual const DL_KeyAgreementAlgorithm<Element> & GetKeyAgreementAlgorithm() const =0;
virtual const DL_KeyDerivationAlgorithm<Element> & GetKeyDerivationAlgorithm() const =0;
virtual const DL_SymmetricEncryptionAlgorithm & GetSymmetricEncryptionAlgorithm() const =0;
};
//! _
template <class T>
class CRYPTOPP_NO_VTABLE DL_DecryptorBase : public DL_CryptoSystemBase<PK_Decryptor, DL_PrivateKey<T> >
{
public:
typedef T Element;
DecodingResult Decrypt(RandomNumberGenerator &rng, const byte *ciphertext, size_t ciphertextLength, byte *plaintext, const NameValuePairs ¶meters = g_nullNameValuePairs) const
{
try
{
const DL_KeyAgreementAlgorithm<T> &agreeAlg = this->GetKeyAgreementAlgorithm();
const DL_KeyDerivationAlgorithm<T> &derivAlg = this->GetKeyDerivationAlgorithm();
const DL_SymmetricEncryptionAlgorithm &encAlg = this->GetSymmetricEncryptionAlgorithm();
const DL_GroupParameters<T> ¶ms = this->GetAbstractGroupParameters();
const DL_PrivateKey<T> &key = this->GetKeyInterface();
Element q = params.DecodeElement(ciphertext, true);
size_t elementSize = params.GetEncodedElementSize(true);
ciphertext += elementSize;
ciphertextLength -= elementSize;
Element z = agreeAlg.AgreeWithStaticPrivateKey(params, q, true, key.GetPrivateExponent());
SecByteBlock derivedKey(encAlg.GetSymmetricKeyLength(encAlg.GetMaxSymmetricPlaintextLength(ciphertextLength)));
derivAlg.Derive(params, derivedKey, derivedKey.size(), z, q, parameters);
return encAlg.SymmetricDecrypt(derivedKey, ciphertext, ciphertextLength, plaintext, parameters);
}
catch (DL_BadElement &)
{
return DecodingResult();
}
}
};
//! _
template <class T>
class CRYPTOPP_NO_VTABLE DL_EncryptorBase : public DL_CryptoSystemBase<PK_Encryptor, DL_PublicKey<T> >
{
public:
typedef T Element;
void Encrypt(RandomNumberGenerator &rng, const byte *plaintext, size_t plaintextLength, byte *ciphertext, const NameValuePairs ¶meters = g_nullNameValuePairs) const
{
const DL_KeyAgreementAlgorithm<T> &agreeAlg = this->GetKeyAgreementAlgorithm();
const DL_KeyDerivationAlgorithm<T> &derivAlg = this->GetKeyDerivationAlgorithm();
const DL_SymmetricEncryptionAlgorithm &encAlg = this->GetSymmetricEncryptionAlgorithm();
const DL_GroupParameters<T> ¶ms = this->GetAbstractGroupParameters();
const DL_PublicKey<T> &key = this->GetKeyInterface();
Integer x(rng, Integer::One(), params.GetMaxExponent());
Element q = params.ExponentiateBase(x);
params.EncodeElement(true, q, ciphertext);
unsigned int elementSize = params.GetEncodedElementSize(true);
ciphertext += elementSize;
Element z = agreeAlg.AgreeWithEphemeralPrivateKey(params, key.GetPublicPrecomputation(), x);
SecByteBlock derivedKey(encAlg.GetSymmetricKeyLength(plaintextLength));
derivAlg.Derive(params, derivedKey, derivedKey.size(), z, q, parameters);
encAlg.SymmetricEncrypt(rng, derivedKey, plaintext, plaintextLength, ciphertext, parameters);
}
};
//! _
template <class T1, class T2>
struct DL_SchemeOptionsBase
{
typedef T1 AlgorithmInfo;
typedef T2 GroupParameters;
typedef typename GroupParameters::Element Element;
};
//! _
template <class T1, class T2>
struct DL_KeyedSchemeOptions : public DL_SchemeOptionsBase<T1, typename T2::PublicKey::GroupParameters>
{
typedef T2 Keys;
typedef typename Keys::PrivateKey PrivateKey;
typedef typename Keys::PublicKey PublicKey;
};
//! _
template <class T1, class T2, class T3, class T4, class T5>
struct DL_SignatureSchemeOptions : public DL_KeyedSchemeOptions<T1, T2>
{
typedef T3 SignatureAlgorithm;
typedef T4 MessageEncodingMethod;
typedef T5 HashFunction;
};
//! _
template <class T1, class T2, class T3, class T4, class T5>
struct DL_CryptoSchemeOptions : public DL_KeyedSchemeOptions<T1, T2>
{
typedef T3 KeyAgreementAlgorithm;
typedef T4 KeyDerivationAlgorithm;
typedef T5 SymmetricEncryptionAlgorithm;
};
//! _
template <class BASE, class SCHEME_OPTIONS, class KEY>
class CRYPTOPP_NO_VTABLE DL_ObjectImplBase : public AlgorithmImpl<BASE, typename SCHEME_OPTIONS::AlgorithmInfo>
{
public:
typedef SCHEME_OPTIONS SchemeOptions;
typedef typename KEY::Element Element;
PrivateKey & AccessPrivateKey() {return m_key;}
PublicKey & AccessPublicKey() {return m_key;}
// KeyAccessor
const KEY & GetKey() const {return m_key;}
KEY & AccessKey() {return m_key;}
protected:
typename BASE::KeyInterface & AccessKeyInterface() {return m_key;}
const typename BASE::KeyInterface & GetKeyInterface() const {return m_key;}
// for signature scheme
HashIdentifier GetHashIdentifier() const
{
typedef typename SchemeOptions::MessageEncodingMethod::HashIdentifierLookup HashLookup;
return HashLookup::template HashIdentifierLookup2<CPP_TYPENAME SchemeOptions::HashFunction>::Lookup();
}
size_t GetDigestSize() const
{
typedef CPP_TYPENAME SchemeOptions::HashFunction H;
return H::DIGESTSIZE;
}
private:
KEY m_key;
};
//! _
template <class BASE, class SCHEME_OPTIONS, class KEY>
class CRYPTOPP_NO_VTABLE DL_ObjectImpl : public DL_ObjectImplBase<BASE, SCHEME_OPTIONS, KEY>
{
public:
typedef typename KEY::Element Element;
protected:
const DL_ElgamalLikeSignatureAlgorithm<Element> & GetSignatureAlgorithm() const
{return Singleton<CPP_TYPENAME SCHEME_OPTIONS::SignatureAlgorithm>().Ref();}
const DL_KeyAgreementAlgorithm<Element> & GetKeyAgreementAlgorithm() const
{return Singleton<CPP_TYPENAME SCHEME_OPTIONS::KeyAgreementAlgorithm>().Ref();}
const DL_KeyDerivationAlgorithm<Element> & GetKeyDerivationAlgorithm() const
{return Singleton<CPP_TYPENAME SCHEME_OPTIONS::KeyDerivationAlgorithm>().Ref();}
const DL_SymmetricEncryptionAlgorithm & GetSymmetricEncryptionAlgorithm() const
{return Singleton<CPP_TYPENAME SCHEME_OPTIONS::SymmetricEncryptionAlgorithm>().Ref();}
HashIdentifier GetHashIdentifier() const
{return HashIdentifier();}
const PK_SignatureMessageEncodingMethod & GetMessageEncodingInterface() const
{return Singleton<CPP_TYPENAME SCHEME_OPTIONS::MessageEncodingMethod>().Ref();}
};
//! _
template <class SCHEME_OPTIONS>
class DL_SignerImpl : public DL_ObjectImpl<DL_SignerBase<typename SCHEME_OPTIONS::Element>, SCHEME_OPTIONS, typename SCHEME_OPTIONS::PrivateKey>
{
public:
PK_MessageAccumulator * NewSignatureAccumulator(RandomNumberGenerator &rng) const
{
std::auto_ptr<PK_MessageAccumulatorBase> p(new PK_MessageAccumulatorImpl<CPP_TYPENAME SCHEME_OPTIONS::HashFunction>);
this->RestartMessageAccumulator(rng, *p);
return p.release();
}
};
//! _
template <class SCHEME_OPTIONS>
class DL_VerifierImpl : public DL_ObjectImpl<DL_VerifierBase<typename SCHEME_OPTIONS::Element>, SCHEME_OPTIONS, typename SCHEME_OPTIONS::PublicKey>
{
public:
PK_MessageAccumulator * NewVerificationAccumulator() const
{
return new PK_MessageAccumulatorImpl<CPP_TYPENAME SCHEME_OPTIONS::HashFunction>;
}
};
//! _
template <class SCHEME_OPTIONS>
class DL_EncryptorImpl : public DL_ObjectImpl<DL_EncryptorBase<typename SCHEME_OPTIONS::Element>, SCHEME_OPTIONS, typename SCHEME_OPTIONS::PublicKey>
{
};
//! _
template <class SCHEME_OPTIONS>
class DL_DecryptorImpl : public DL_ObjectImpl<DL_DecryptorBase<typename SCHEME_OPTIONS::Element>, SCHEME_OPTIONS, typename SCHEME_OPTIONS::PrivateKey>
{
};
// ********************************************************
//! _
template <class T>
class CRYPTOPP_NO_VTABLE DL_SimpleKeyAgreementDomainBase : public SimpleKeyAgreementDomain
{
public:
typedef T Element;
CryptoParameters & AccessCryptoParameters() {return AccessAbstractGroupParameters();}
unsigned int AgreedValueLength() const {return GetAbstractGroupParameters().GetEncodedElementSize(false);}
unsigned int PrivateKeyLength() const {return GetAbstractGroupParameters().GetSubgroupOrder().ByteCount();}
unsigned int PublicKeyLength() const {return GetAbstractGroupParameters().GetEncodedElementSize(true);}
void GeneratePrivateKey(RandomNumberGenerator &rng, byte *privateKey) const
{
Integer x(rng, Integer::One(), GetAbstractGroupParameters().GetMaxExponent());
x.Encode(privateKey, PrivateKeyLength());
}
void GeneratePublicKey(RandomNumberGenerator &rng, const byte *privateKey, byte *publicKey) const
{
const DL_GroupParameters<T> ¶ms = GetAbstractGroupParameters();
Integer x(privateKey, PrivateKeyLength());
Element y = params.ExponentiateBase(x);
params.EncodeElement(true, y, publicKey);
}
bool Agree(byte *agreedValue, const byte *privateKey, const byte *otherPublicKey, bool validateOtherPublicKey=true) const
{
try
{
const DL_GroupParameters<T> ¶ms = GetAbstractGroupParameters();
Integer x(privateKey, PrivateKeyLength());
Element w = params.DecodeElement(otherPublicKey, validateOtherPublicKey);
Element z = GetKeyAgreementAlgorithm().AgreeWithStaticPrivateKey(
GetAbstractGroupParameters(), w, validateOtherPublicKey, x);
params.EncodeElement(false, z, agreedValue);
}
catch (DL_BadElement &)
{
return false;
}
return true;
}
const Element &GetGenerator() const {return GetAbstractGroupParameters().GetSubgroupGenerator();}
protected:
virtual const DL_KeyAgreementAlgorithm<Element> & GetKeyAgreementAlgorithm() const =0;
virtual DL_GroupParameters<Element> & AccessAbstractGroupParameters() =0;
const DL_GroupParameters<Element> & GetAbstractGroupParameters() const {return const_cast<DL_SimpleKeyAgreementDomainBase<Element> *>(this)->AccessAbstractGroupParameters();}
};
enum CofactorMultiplicationOption {NO_COFACTOR_MULTIPLICTION, COMPATIBLE_COFACTOR_MULTIPLICTION, INCOMPATIBLE_COFACTOR_MULTIPLICTION};
typedef EnumToType<CofactorMultiplicationOption, NO_COFACTOR_MULTIPLICTION> NoCofactorMultiplication;
typedef EnumToType<CofactorMultiplicationOption, COMPATIBLE_COFACTOR_MULTIPLICTION> CompatibleCofactorMultiplication;
typedef EnumToType<CofactorMultiplicationOption, INCOMPATIBLE_COFACTOR_MULTIPLICTION> IncompatibleCofactorMultiplication;
//! DH key agreement algorithm
template <class ELEMENT, class COFACTOR_OPTION>
class DL_KeyAgreementAlgorithm_DH : public DL_KeyAgreementAlgorithm<ELEMENT>
{
public:
typedef ELEMENT Element;
static const char * CRYPTOPP_API StaticAlgorithmName()
{return COFACTOR_OPTION::ToEnum() == INCOMPATIBLE_COFACTOR_MULTIPLICTION ? "DHC" : "DH";}
Element AgreeWithEphemeralPrivateKey(const DL_GroupParameters<Element> ¶ms, const DL_FixedBasePrecomputation<Element> &publicPrecomputation, const Integer &privateExponent) const
{
return publicPrecomputation.Exponentiate(params.GetGroupPrecomputation(),
COFACTOR_OPTION::ToEnum() == INCOMPATIBLE_COFACTOR_MULTIPLICTION ? privateExponent*params.GetCofactor() : privateExponent);
}
Element AgreeWithStaticPrivateKey(const DL_GroupParameters<Element> ¶ms, const Element &publicElement, bool validateOtherPublicKey, const Integer &privateExponent) const
{
if (COFACTOR_OPTION::ToEnum() == COMPATIBLE_COFACTOR_MULTIPLICTION)
{
const Integer &k = params.GetCofactor();
return params.ExponentiateElement(publicElement,
ModularArithmetic(params.GetSubgroupOrder()).Divide(privateExponent, k)*k);
}
else if (COFACTOR_OPTION::ToEnum() == INCOMPATIBLE_COFACTOR_MULTIPLICTION)
return params.ExponentiateElement(publicElement, privateExponent*params.GetCofactor());
else
{
assert(COFACTOR_OPTION::ToEnum() == NO_COFACTOR_MULTIPLICTION);
if (!validateOtherPublicKey)
return params.ExponentiateElement(publicElement, privateExponent);
if (params.FastSubgroupCheckAvailable())
{
if (!params.ValidateElement(2, publicElement, NULL))
throw DL_BadElement();
return params.ExponentiateElement(publicElement, privateExponent);
}
else
{
const Integer e[2] = {params.GetSubgroupOrder(), privateExponent};
Element r[2];
params.SimultaneousExponentiate(r, publicElement, e, 2);
if (!params.IsIdentity(r[0]))
throw DL_BadElement();
return r[1];
}
}
}
};
// ********************************************************
//! A template implementing constructors for public key algorithm classes
template <class BASE>
class CRYPTOPP_NO_VTABLE PK_FinalTemplate : public BASE
{
public:
PK_FinalTemplate() {}
PK_FinalTemplate(const CryptoMaterial &key)
{this->AccessKey().AssignFrom(key);}
PK_FinalTemplate(BufferedTransformation &bt)
{this->AccessKey().BERDecode(bt);}
PK_FinalTemplate(const AsymmetricAlgorithm &algorithm)
{this->AccessKey().AssignFrom(algorithm.GetMaterial());}
PK_FinalTemplate(const Integer &v1)
{this->AccessKey().Initialize(v1);}
#if (defined(_MSC_VER) && _MSC_VER < 1300)
template <class T1, class T2>
PK_FinalTemplate(T1 &v1, T2 &v2)
{this->AccessKey().Initialize(v1, v2);}
template <class T1, class T2, class T3>
PK_FinalTemplate(T1 &v1, T2 &v2, T3 &v3)
{this->AccessKey().Initialize(v1, v2, v3);}
template <class T1, class T2, class T3, class T4>
PK_FinalTemplate(T1 &v1, T2 &v2, T3 &v3, T4 &v4)
{this->AccessKey().Initialize(v1, v2, v3, v4);}
template <class T1, class T2, class T3, class T4, class T5>
PK_FinalTemplate(T1 &v1, T2 &v2, T3 &v3, T4 &v4, T5 &v5)
{this->AccessKey().Initialize(v1, v2, v3, v4, v5);}
template <class T1, class T2, class T3, class T4, class T5, class T6>
PK_FinalTemplate(T1 &v1, T2 &v2, T3 &v3, T4 &v4, T5 &v5, T6 &v6)
{this->AccessKey().Initialize(v1, v2, v3, v4, v5, v6);}
template <class T1, class T2, class T3, class T4, class T5, class T6, class T7>
PK_FinalTemplate(T1 &v1, T2 &v2, T3 &v3, T4 &v4, T5 &v5, T6 &v6, T7 &v7)
{this->AccessKey().Initialize(v1, v2, v3, v4, v5, v6, v7);}
template <class T1, class T2, class T3, class T4, class T5, class T6, class T7, class T8>
PK_FinalTemplate(T1 &v1, T2 &v2, T3 &v3, T4 &v4, T5 &v5, T6 &v6, T7 &v7, T8 &v8)
{this->AccessKey().Initialize(v1, v2, v3, v4, v5, v6, v7, v8);}
#else
template <class T1, class T2>
PK_FinalTemplate(const T1 &v1, const T2 &v2)
{this->AccessKey().Initialize(v1, v2);}
template <class T1, class T2, class T3>
PK_FinalTemplate(const T1 &v1, const T2 &v2, const T3 &v3)
{this->AccessKey().Initialize(v1, v2, v3);}
template <class T1, class T2, class T3, class T4>
PK_FinalTemplate(const T1 &v1, const T2 &v2, const T3 &v3, const T4 &v4)
{this->AccessKey().Initialize(v1, v2, v3, v4);}
template <class T1, class T2, class T3, class T4, class T5>
PK_FinalTemplate(const T1 &v1, const T2 &v2, const T3 &v3, const T4 &v4, const T5 &v5)
{this->AccessKey().Initialize(v1, v2, v3, v4, v5);}
template <class T1, class T2, class T3, class T4, class T5, class T6>
PK_FinalTemplate(const T1 &v1, const T2 &v2, const T3 &v3, const T4 &v4, const T5 &v5, const T6 &v6)
{this->AccessKey().Initialize(v1, v2, v3, v4, v5, v6);}
template <class T1, class T2, class T3, class T4, class T5, class T6, class T7>
PK_FinalTemplate(const T1 &v1, const T2 &v2, const T3 &v3, const T4 &v4, const T5 &v5, const T6 &v6, const T7 &v7)
{this->AccessKey().Initialize(v1, v2, v3, v4, v5, v6, v7);}
template <class T1, class T2, class T3, class T4, class T5, class T6, class T7, class T8>
PK_FinalTemplate(const T1 &v1, const T2 &v2, const T3 &v3, const T4 &v4, const T5 &v5, const T6 &v6, const T7 &v7, const T8 &v8)
{this->AccessKey().Initialize(v1, v2, v3, v4, v5, v6, v7, v8);}
template <class T1, class T2>
PK_FinalTemplate(T1 &v1, const T2 &v2)
{this->AccessKey().Initialize(v1, v2);}
template <class T1, class T2, class T3>
PK_FinalTemplate(T1 &v1, const T2 &v2, const T3 &v3)
{this->AccessKey().Initialize(v1, v2, v3);}
template <class T1, class T2, class T3, class T4>
PK_FinalTemplate(T1 &v1, const T2 &v2, const T3 &v3, const T4 &v4)
{this->AccessKey().Initialize(v1, v2, v3, v4);}
template <class T1, class T2, class T3, class T4, class T5>
PK_FinalTemplate(T1 &v1, const T2 &v2, const T3 &v3, const T4 &v4, const T5 &v5)
{this->AccessKey().Initialize(v1, v2, v3, v4, v5);}
template <class T1, class T2, class T3, class T4, class T5, class T6>
PK_FinalTemplate(T1 &v1, const T2 &v2, const T3 &v3, const T4 &v4, const T5 &v5, const T6 &v6)
{this->AccessKey().Initialize(v1, v2, v3, v4, v5, v6);}
template <class T1, class T2, class T3, class T4, class T5, class T6, class T7>
PK_FinalTemplate(T1 &v1, const T2 &v2, const T3 &v3, const T4 &v4, const T5 &v5, const T6 &v6, const T7 &v7)
{this->AccessKey().Initialize(v1, v2, v3, v4, v5, v6, v7);}
template <class T1, class T2, class T3, class T4, class T5, class T6, class T7, class T8>
PK_FinalTemplate(T1 &v1, const T2 &v2, const T3 &v3, const T4 &v4, const T5 &v5, const T6 &v6, const T7 &v7, const T8 &v8)
{this->AccessKey().Initialize(v1, v2, v3, v4, v5, v6, v7, v8);}
#endif
};
//! Base class for public key encryption standard classes. These classes are used to select from variants of algorithms. Note that not all standards apply to all algorithms.
struct EncryptionStandard {};
//! Base class for public key signature standard classes. These classes are used to select from variants of algorithms. Note that not all standards apply to all algorithms.
struct SignatureStandard {};
template <class STANDARD, class KEYS, class ALG_INFO>
class TF_ES;
//! Trapdoor Function Based Encryption Scheme
template <class STANDARD, class KEYS, class ALG_INFO = TF_ES<STANDARD, KEYS, int> >
class TF_ES : public KEYS
{
typedef typename STANDARD::EncryptionMessageEncodingMethod MessageEncodingMethod;
public:
//! see EncryptionStandard for a list of standards
typedef STANDARD Standard;
typedef TF_CryptoSchemeOptions<ALG_INFO, KEYS, MessageEncodingMethod> SchemeOptions;
static std::string CRYPTOPP_API StaticAlgorithmName() {return std::string(KEYS::StaticAlgorithmName()) + "/" + MessageEncodingMethod::StaticAlgorithmName();}
//! implements PK_Decryptor interface
typedef PK_FinalTemplate<TF_DecryptorImpl<SchemeOptions> > Decryptor;
//! implements PK_Encryptor interface
typedef PK_FinalTemplate<TF_EncryptorImpl<SchemeOptions> > Encryptor;
};
template <class STANDARD, class H, class KEYS, class ALG_INFO> // VC60 workaround: doesn't work if KEYS is first parameter
class TF_SS;
//! Trapdoor Function Based Signature Scheme
template <class STANDARD, class H, class KEYS, class ALG_INFO = TF_SS<STANDARD, H, KEYS, int> > // VC60 workaround: doesn't work if KEYS is first parameter
class TF_SS : public KEYS
{
public:
//! see SignatureStandard for a list of standards
typedef STANDARD Standard;
typedef typename Standard::SignatureMessageEncodingMethod MessageEncodingMethod;
typedef TF_SignatureSchemeOptions<ALG_INFO, KEYS, MessageEncodingMethod, H> SchemeOptions;
static std::string CRYPTOPP_API StaticAlgorithmName() {return std::string(KEYS::StaticAlgorithmName()) + "/" + MessageEncodingMethod::StaticAlgorithmName() + "(" + H::StaticAlgorithmName() + ")";}
//! implements PK_Signer interface
typedef PK_FinalTemplate<TF_SignerImpl<SchemeOptions> > Signer;
//! implements PK_Verifier interface
typedef PK_FinalTemplate<TF_VerifierImpl<SchemeOptions> > Verifier;
};
template <class KEYS, class SA, class MEM, class H, class ALG_INFO>
class DL_SS;
//! Discrete Log Based Signature Scheme
template <class KEYS, class SA, class MEM, class H, class ALG_INFO = DL_SS<KEYS, SA, MEM, H, int> >
class DL_SS : public KEYS
{
typedef DL_SignatureSchemeOptions<ALG_INFO, KEYS, SA, MEM, H> SchemeOptions;
public:
static std::string StaticAlgorithmName() {return SA::StaticAlgorithmName() + std::string("/EMSA1(") + H::StaticAlgorithmName() + ")";}
//! implements PK_Signer interface
typedef PK_FinalTemplate<DL_SignerImpl<SchemeOptions> > Signer;
//! implements PK_Verifier interface
typedef PK_FinalTemplate<DL_VerifierImpl<SchemeOptions> > Verifier;
};
//! Discrete Log Based Encryption Scheme
template <class KEYS, class AA, class DA, class EA, class ALG_INFO>
class DL_ES : public KEYS
{
typedef DL_CryptoSchemeOptions<ALG_INFO, KEYS, AA, DA, EA> SchemeOptions;
public:
//! implements PK_Decryptor interface
typedef PK_FinalTemplate<DL_DecryptorImpl<SchemeOptions> > Decryptor;
//! implements PK_Encryptor interface
typedef PK_FinalTemplate<DL_EncryptorImpl<SchemeOptions> > Encryptor;
};
NAMESPACE_END
#endif
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