mirror of
https://github.com/shadps4-emu/ext-cryptopp.git
synced 2024-11-27 11:50:29 +00:00
538 lines
19 KiB
C++
538 lines
19 KiB
C++
#ifndef CRYPTOPP_GFPCRYPT_H
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#define CRYPTOPP_GFPCRYPT_H
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/** \file
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Implementation of schemes based on DL over GF(p)
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*/
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#include "pubkey.h"
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#include "modexppc.h"
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#include "sha.h"
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#include "algparam.h"
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#include "asn.h"
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#include "smartptr.h"
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#include "hmac.h"
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#include <limits.h>
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NAMESPACE_BEGIN(CryptoPP)
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CRYPTOPP_DLL_TEMPLATE_CLASS DL_GroupParameters<Integer>;
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//! _
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class CRYPTOPP_DLL CRYPTOPP_NO_VTABLE DL_GroupParameters_IntegerBased : public ASN1CryptoMaterial<DL_GroupParameters<Integer> >
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{
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typedef DL_GroupParameters_IntegerBased ThisClass;
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public:
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virtual ~DL_GroupParameters_IntegerBased() { }
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void Initialize(const DL_GroupParameters_IntegerBased ¶ms)
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{Initialize(params.GetModulus(), params.GetSubgroupOrder(), params.GetSubgroupGenerator());}
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void Initialize(RandomNumberGenerator &rng, unsigned int pbits)
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{GenerateRandom(rng, MakeParameters("ModulusSize", (int)pbits));}
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void Initialize(const Integer &p, const Integer &g)
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{SetModulusAndSubgroupGenerator(p, g); SetSubgroupOrder(ComputeGroupOrder(p)/2);}
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void Initialize(const Integer &p, const Integer &q, const Integer &g)
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{SetModulusAndSubgroupGenerator(p, g); SetSubgroupOrder(q);}
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// ASN1Object interface
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void BERDecode(BufferedTransformation &bt);
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void DEREncode(BufferedTransformation &bt) const;
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// GeneratibleCryptoMaterial interface
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/*! parameters: (ModulusSize, SubgroupOrderSize (optional)) */
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void GenerateRandom(RandomNumberGenerator &rng, const NameValuePairs &alg);
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bool GetVoidValue(const char *name, const std::type_info &valueType, void *pValue) const;
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void AssignFrom(const NameValuePairs &source);
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// DL_GroupParameters
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const Integer & GetSubgroupOrder() const {return m_q;}
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Integer GetGroupOrder() const {return GetFieldType() == 1 ? GetModulus()-Integer::One() : GetModulus()+Integer::One();}
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bool ValidateGroup(RandomNumberGenerator &rng, unsigned int level) const;
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bool ValidateElement(unsigned int level, const Integer &element, const DL_FixedBasePrecomputation<Integer> *precomp) const;
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bool FastSubgroupCheckAvailable() const {return GetCofactor() == 2;}
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void EncodeElement(bool reversible, const Element &element, byte *encoded) const
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{element.Encode(encoded, GetModulus().ByteCount());}
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unsigned int GetEncodedElementSize(bool reversible) const {return GetModulus().ByteCount();}
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Integer DecodeElement(const byte *encoded, bool checkForGroupMembership) const;
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Integer ConvertElementToInteger(const Element &element) const
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{return element;}
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Integer GetMaxExponent() const;
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static std::string CRYPTOPP_API StaticAlgorithmNamePrefix() {return "";}
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OID GetAlgorithmID() const;
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virtual const Integer & GetModulus() const =0;
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virtual void SetModulusAndSubgroupGenerator(const Integer &p, const Integer &g) =0;
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void SetSubgroupOrder(const Integer &q)
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{m_q = q; ParametersChanged();}
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protected:
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Integer ComputeGroupOrder(const Integer &modulus) const
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{return modulus-(GetFieldType() == 1 ? 1 : -1);}
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// GF(p) = 1, GF(p^2) = 2
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virtual int GetFieldType() const =0;
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virtual unsigned int GetDefaultSubgroupOrderSize(unsigned int modulusSize) const;
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private:
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Integer m_q;
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};
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//! _
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template <class GROUP_PRECOMP, class BASE_PRECOMP = DL_FixedBasePrecomputationImpl<CPP_TYPENAME GROUP_PRECOMP::Element> >
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class CRYPTOPP_NO_VTABLE DL_GroupParameters_IntegerBasedImpl : public DL_GroupParametersImpl<GROUP_PRECOMP, BASE_PRECOMP, DL_GroupParameters_IntegerBased>
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{
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typedef DL_GroupParameters_IntegerBasedImpl<GROUP_PRECOMP, BASE_PRECOMP> ThisClass;
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public:
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typedef typename GROUP_PRECOMP::Element Element;
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virtual ~DL_GroupParameters_IntegerBasedImpl() { }
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// GeneratibleCryptoMaterial interface
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bool GetVoidValue(const char *name, const std::type_info &valueType, void *pValue) const
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{return GetValueHelper<DL_GroupParameters_IntegerBased>(this, name, valueType, pValue).Assignable();}
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void AssignFrom(const NameValuePairs &source)
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{AssignFromHelper<DL_GroupParameters_IntegerBased>(this, source);}
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// DL_GroupParameters
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const DL_FixedBasePrecomputation<Element> & GetBasePrecomputation() const {return this->m_gpc;}
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DL_FixedBasePrecomputation<Element> & AccessBasePrecomputation() {return this->m_gpc;}
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// IntegerGroupParameters
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const Integer & GetModulus() const {return this->m_groupPrecomputation.GetModulus();}
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const Integer & GetGenerator() const {return this->m_gpc.GetBase(this->GetGroupPrecomputation());}
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void SetModulusAndSubgroupGenerator(const Integer &p, const Integer &g) // these have to be set together
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{this->m_groupPrecomputation.SetModulus(p); this->m_gpc.SetBase(this->GetGroupPrecomputation(), g); this->ParametersChanged();}
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// non-inherited
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bool operator==(const DL_GroupParameters_IntegerBasedImpl<GROUP_PRECOMP, BASE_PRECOMP> &rhs) const
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{return GetModulus() == rhs.GetModulus() && GetGenerator() == rhs.GetGenerator() && this->GetSubgroupOrder() == rhs.GetSubgroupOrder();}
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bool operator!=(const DL_GroupParameters_IntegerBasedImpl<GROUP_PRECOMP, BASE_PRECOMP> &rhs) const
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{return !operator==(rhs);}
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};
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CRYPTOPP_DLL_TEMPLATE_CLASS DL_GroupParameters_IntegerBasedImpl<ModExpPrecomputation>;
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//! GF(p) group parameters
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class CRYPTOPP_DLL DL_GroupParameters_GFP : public DL_GroupParameters_IntegerBasedImpl<ModExpPrecomputation>
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{
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public:
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virtual ~DL_GroupParameters_GFP() { }
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// DL_GroupParameters
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bool IsIdentity(const Integer &element) const {return element == Integer::One();}
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void SimultaneousExponentiate(Element *results, const Element &base, const Integer *exponents, unsigned int exponentsCount) const;
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// NameValuePairs interface
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bool GetVoidValue(const char *name, const std::type_info &valueType, void *pValue) const
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{
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return GetValueHelper<DL_GroupParameters_IntegerBased>(this, name, valueType, pValue).Assignable();
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}
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// used by MQV
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Element MultiplyElements(const Element &a, const Element &b) const;
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Element CascadeExponentiate(const Element &element1, const Integer &exponent1, const Element &element2, const Integer &exponent2) const;
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protected:
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int GetFieldType() const {return 1;}
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};
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//! GF(p) group parameters that default to same primes
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class CRYPTOPP_DLL DL_GroupParameters_GFP_DefaultSafePrime : public DL_GroupParameters_GFP
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{
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public:
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typedef NoCofactorMultiplication DefaultCofactorOption;
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protected:
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unsigned int GetDefaultSubgroupOrderSize(unsigned int modulusSize) const {return modulusSize-1;}
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};
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//! GDSA algorithm
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template <class T>
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class DL_Algorithm_GDSA : public DL_ElgamalLikeSignatureAlgorithm<T>
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{
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public:
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virtual ~DL_Algorithm_GDSA() { }
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static const char * CRYPTOPP_API StaticAlgorithmName() {return "DSA-1363";}
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void Sign(const DL_GroupParameters<T> ¶ms, const Integer &x, const Integer &k, const Integer &e, Integer &r, Integer &s) const
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{
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const Integer &q = params.GetSubgroupOrder();
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r %= q;
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Integer kInv = k.InverseMod(q);
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s = (kInv * (x*r + e)) % q;
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assert(!!r && !!s);
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}
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bool Verify(const DL_GroupParameters<T> ¶ms, const DL_PublicKey<T> &publicKey, const Integer &e, const Integer &r, const Integer &s) const
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{
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const Integer &q = params.GetSubgroupOrder();
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if (r>=q || r<1 || s>=q || s<1)
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return false;
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Integer w = s.InverseMod(q);
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Integer u1 = (e * w) % q;
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Integer u2 = (r * w) % q;
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// verify r == (g^u1 * y^u2 mod p) mod q
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return r == params.ConvertElementToInteger(publicKey.CascadeExponentiateBaseAndPublicElement(u1, u2)) % q;
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}
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};
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CRYPTOPP_DLL_TEMPLATE_CLASS DL_Algorithm_GDSA<Integer>;
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//! NR algorithm
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template <class T>
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class DL_Algorithm_NR : public DL_ElgamalLikeSignatureAlgorithm<T>
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{
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public:
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virtual ~DL_Algorithm_NR() { }
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static const char * CRYPTOPP_API StaticAlgorithmName() {return "NR";}
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void Sign(const DL_GroupParameters<T> ¶ms, const Integer &x, const Integer &k, const Integer &e, Integer &r, Integer &s) const
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{
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const Integer &q = params.GetSubgroupOrder();
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r = (r + e) % q;
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s = (k - x*r) % q;
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assert(!!r);
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}
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bool Verify(const DL_GroupParameters<T> ¶ms, const DL_PublicKey<T> &publicKey, const Integer &e, const Integer &r, const Integer &s) const
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{
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const Integer &q = params.GetSubgroupOrder();
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if (r>=q || r<1 || s>=q)
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return false;
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// check r == (m_g^s * m_y^r + m) mod m_q
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return r == (params.ConvertElementToInteger(publicKey.CascadeExponentiateBaseAndPublicElement(s, r)) + e) % q;
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}
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};
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/*! DSA public key format is defined in 7.3.3 of RFC 2459. The
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private key format is defined in 12.9 of PKCS #11 v2.10. */
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template <class GP>
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class DL_PublicKey_GFP : public DL_PublicKeyImpl<GP>
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{
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public:
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void Initialize(const DL_GroupParameters_IntegerBased ¶ms, const Integer &y)
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{this->AccessGroupParameters().Initialize(params); this->SetPublicElement(y);}
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void Initialize(const Integer &p, const Integer &g, const Integer &y)
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{this->AccessGroupParameters().Initialize(p, g); this->SetPublicElement(y);}
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void Initialize(const Integer &p, const Integer &q, const Integer &g, const Integer &y)
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{this->AccessGroupParameters().Initialize(p, q, g); this->SetPublicElement(y);}
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// X509PublicKey
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void BERDecodePublicKey(BufferedTransformation &bt, bool, size_t)
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{this->SetPublicElement(Integer(bt));}
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void DEREncodePublicKey(BufferedTransformation &bt) const
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{this->GetPublicElement().DEREncode(bt);}
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};
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//! DL private key (in GF(p) groups)
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template <class GP>
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class DL_PrivateKey_GFP : public DL_PrivateKeyImpl<GP>
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{
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public:
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void Initialize(RandomNumberGenerator &rng, unsigned int modulusBits)
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{this->GenerateRandomWithKeySize(rng, modulusBits);}
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void Initialize(RandomNumberGenerator &rng, const Integer &p, const Integer &g)
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{this->GenerateRandom(rng, MakeParameters("Modulus", p)("SubgroupGenerator", g));}
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void Initialize(RandomNumberGenerator &rng, const Integer &p, const Integer &q, const Integer &g)
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{this->GenerateRandom(rng, MakeParameters("Modulus", p)("SubgroupOrder", q)("SubgroupGenerator", g));}
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void Initialize(const DL_GroupParameters_IntegerBased ¶ms, const Integer &x)
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{this->AccessGroupParameters().Initialize(params); this->SetPrivateExponent(x);}
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void Initialize(const Integer &p, const Integer &g, const Integer &x)
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{this->AccessGroupParameters().Initialize(p, g); this->SetPrivateExponent(x);}
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void Initialize(const Integer &p, const Integer &q, const Integer &g, const Integer &x)
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{this->AccessGroupParameters().Initialize(p, q, g); this->SetPrivateExponent(x);}
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};
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//! DL signing/verification keys (in GF(p) groups)
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struct DL_SignatureKeys_GFP
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{
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typedef DL_GroupParameters_GFP GroupParameters;
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typedef DL_PublicKey_GFP<GroupParameters> PublicKey;
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typedef DL_PrivateKey_GFP<GroupParameters> PrivateKey;
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};
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//! DL encryption/decryption keys (in GF(p) groups)
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struct DL_CryptoKeys_GFP
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{
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typedef DL_GroupParameters_GFP_DefaultSafePrime GroupParameters;
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typedef DL_PublicKey_GFP<GroupParameters> PublicKey;
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typedef DL_PrivateKey_GFP<GroupParameters> PrivateKey;
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};
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//! provided for backwards compatibility, this class uses the old non-standard Crypto++ key format
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template <class BASE>
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class DL_PublicKey_GFP_OldFormat : public BASE
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{
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public:
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void BERDecode(BufferedTransformation &bt)
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{
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BERSequenceDecoder seq(bt);
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Integer v1(seq);
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Integer v2(seq);
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Integer v3(seq);
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if (seq.EndReached())
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{
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this->AccessGroupParameters().Initialize(v1, v1/2, v2);
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this->SetPublicElement(v3);
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}
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else
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{
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Integer v4(seq);
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this->AccessGroupParameters().Initialize(v1, v2, v3);
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this->SetPublicElement(v4);
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}
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seq.MessageEnd();
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}
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void DEREncode(BufferedTransformation &bt) const
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{
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DERSequenceEncoder seq(bt);
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this->GetGroupParameters().GetModulus().DEREncode(seq);
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if (this->GetGroupParameters().GetCofactor() != 2)
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this->GetGroupParameters().GetSubgroupOrder().DEREncode(seq);
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this->GetGroupParameters().GetGenerator().DEREncode(seq);
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this->GetPublicElement().DEREncode(seq);
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seq.MessageEnd();
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}
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};
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//! provided for backwards compatibility, this class uses the old non-standard Crypto++ key format
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template <class BASE>
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class DL_PrivateKey_GFP_OldFormat : public BASE
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{
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public:
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void BERDecode(BufferedTransformation &bt)
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{
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BERSequenceDecoder seq(bt);
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Integer v1(seq);
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Integer v2(seq);
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Integer v3(seq);
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Integer v4(seq);
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if (seq.EndReached())
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{
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this->AccessGroupParameters().Initialize(v1, v1/2, v2);
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this->SetPrivateExponent(v4 % (v1/2)); // some old keys may have x >= q
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}
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else
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{
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Integer v5(seq);
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this->AccessGroupParameters().Initialize(v1, v2, v3);
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this->SetPrivateExponent(v5);
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}
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seq.MessageEnd();
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}
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void DEREncode(BufferedTransformation &bt) const
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{
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DERSequenceEncoder seq(bt);
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this->GetGroupParameters().GetModulus().DEREncode(seq);
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if (this->GetGroupParameters().GetCofactor() != 2)
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this->GetGroupParameters().GetSubgroupOrder().DEREncode(seq);
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this->GetGroupParameters().GetGenerator().DEREncode(seq);
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this->GetGroupParameters().ExponentiateBase(this->GetPrivateExponent()).DEREncode(seq);
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this->GetPrivateExponent().DEREncode(seq);
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seq.MessageEnd();
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}
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};
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//! <a href="http://www.weidai.com/scan-mirror/sig.html#DSA-1363">DSA-1363</a>
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template <class H>
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struct GDSA : public DL_SS<
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DL_SignatureKeys_GFP,
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DL_Algorithm_GDSA<Integer>,
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DL_SignatureMessageEncodingMethod_DSA,
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H>
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{
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};
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//! <a href="http://www.weidai.com/scan-mirror/sig.html#NR">NR</a>
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template <class H>
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struct NR : public DL_SS<
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DL_SignatureKeys_GFP,
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DL_Algorithm_NR<Integer>,
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DL_SignatureMessageEncodingMethod_NR,
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H>
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{
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};
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//! DSA group parameters, these are GF(p) group parameters that are allowed by the DSA standard
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class CRYPTOPP_DLL DL_GroupParameters_DSA : public DL_GroupParameters_GFP
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{
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public:
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/*! also checks that the lengths of p and q are allowed by the DSA standard */
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bool ValidateGroup(RandomNumberGenerator &rng, unsigned int level) const;
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/*! parameters: (ModulusSize), or (Modulus, SubgroupOrder, SubgroupGenerator) */
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/*! ModulusSize must be between DSA::MIN_PRIME_LENGTH and DSA::MAX_PRIME_LENGTH, and divisible by DSA::PRIME_LENGTH_MULTIPLE */
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void GenerateRandom(RandomNumberGenerator &rng, const NameValuePairs &alg);
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static bool CRYPTOPP_API IsValidPrimeLength(unsigned int pbits)
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{return pbits >= MIN_PRIME_LENGTH && pbits <= MAX_PRIME_LENGTH && pbits % PRIME_LENGTH_MULTIPLE == 0;}
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enum {MIN_PRIME_LENGTH = 1024, MAX_PRIME_LENGTH = 3072, PRIME_LENGTH_MULTIPLE = 1024};
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};
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template <class H>
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class DSA2;
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//! DSA keys
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struct DL_Keys_DSA
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{
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typedef DL_PublicKey_GFP<DL_GroupParameters_DSA> PublicKey;
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typedef DL_PrivateKey_WithSignaturePairwiseConsistencyTest<DL_PrivateKey_GFP<DL_GroupParameters_DSA>, DSA2<SHA> > PrivateKey;
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};
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//! <a href="http://en.wikipedia.org/wiki/Digital_Signature_Algorithm">DSA</a>, as specified in FIPS 186-3
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// class named DSA2 instead of DSA for backwards compatibility (DSA was a non-template class)
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template <class H>
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class DSA2 : public DL_SS<
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DL_Keys_DSA,
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DL_Algorithm_GDSA<Integer>,
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DL_SignatureMessageEncodingMethod_DSA,
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H,
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DSA2<H> >
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{
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public:
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static std::string CRYPTOPP_API StaticAlgorithmName() {return "DSA/" + (std::string)H::StaticAlgorithmName();}
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};
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//! DSA with SHA-1, typedef'd for backwards compatibility
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typedef DSA2<SHA> DSA;
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CRYPTOPP_DLL_TEMPLATE_CLASS DL_PublicKey_GFP<DL_GroupParameters_DSA>;
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CRYPTOPP_DLL_TEMPLATE_CLASS DL_PrivateKey_GFP<DL_GroupParameters_DSA>;
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CRYPTOPP_DLL_TEMPLATE_CLASS DL_PrivateKey_WithSignaturePairwiseConsistencyTest<DL_PrivateKey_GFP<DL_GroupParameters_DSA>, DSA2<SHA> >;
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//! the XOR encryption method, for use with DL-based cryptosystems
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template <class MAC, bool DHAES_MODE>
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class DL_EncryptionAlgorithm_Xor : public DL_SymmetricEncryptionAlgorithm
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{
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public:
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virtual ~DL_EncryptionAlgorithm_Xor() { }
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bool ParameterSupported(const char *name) const {return strcmp(name, Name::EncodingParameters()) == 0;}
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size_t GetSymmetricKeyLength(size_t plaintextLength) const
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{return plaintextLength + MAC::DEFAULT_KEYLENGTH;}
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size_t GetSymmetricCiphertextLength(size_t plaintextLength) const
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{return plaintextLength + MAC::DIGESTSIZE;}
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size_t GetMaxSymmetricPlaintextLength(size_t ciphertextLength) const
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{return (unsigned int)SaturatingSubtract(ciphertextLength, (unsigned int)MAC::DIGESTSIZE);}
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void SymmetricEncrypt(RandomNumberGenerator &rng, const byte *key, const byte *plaintext, size_t plaintextLength, byte *ciphertext, const NameValuePairs ¶meters) const
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{
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const byte *cipherKey, *macKey;
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if (DHAES_MODE)
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{
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macKey = key;
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cipherKey = key + MAC::DEFAULT_KEYLENGTH;
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}
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else
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{
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cipherKey = key;
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macKey = key + plaintextLength;
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}
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ConstByteArrayParameter encodingParameters;
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parameters.GetValue(Name::EncodingParameters(), encodingParameters);
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xorbuf(ciphertext, plaintext, cipherKey, plaintextLength);
|
|
MAC mac(macKey);
|
|
mac.Update(ciphertext, plaintextLength);
|
|
mac.Update(encodingParameters.begin(), encodingParameters.size());
|
|
if (DHAES_MODE)
|
|
{
|
|
byte L[8] = {0,0,0,0};
|
|
PutWord(false, BIG_ENDIAN_ORDER, L+4, word32(encodingParameters.size()));
|
|
mac.Update(L, 8);
|
|
}
|
|
mac.Final(ciphertext + plaintextLength);
|
|
}
|
|
DecodingResult SymmetricDecrypt(const byte *key, const byte *ciphertext, size_t ciphertextLength, byte *plaintext, const NameValuePairs ¶meters) const
|
|
{
|
|
size_t plaintextLength = GetMaxSymmetricPlaintextLength(ciphertextLength);
|
|
const byte *cipherKey, *macKey;
|
|
if (DHAES_MODE)
|
|
{
|
|
macKey = key;
|
|
cipherKey = key + MAC::DEFAULT_KEYLENGTH;
|
|
}
|
|
else
|
|
{
|
|
cipherKey = key;
|
|
macKey = key + plaintextLength;
|
|
}
|
|
|
|
ConstByteArrayParameter encodingParameters;
|
|
parameters.GetValue(Name::EncodingParameters(), encodingParameters);
|
|
|
|
MAC mac(macKey);
|
|
mac.Update(ciphertext, plaintextLength);
|
|
mac.Update(encodingParameters.begin(), encodingParameters.size());
|
|
if (DHAES_MODE)
|
|
{
|
|
byte L[8] = {0,0,0,0};
|
|
PutWord(false, BIG_ENDIAN_ORDER, L+4, word32(encodingParameters.size()));
|
|
mac.Update(L, 8);
|
|
}
|
|
if (!mac.Verify(ciphertext + plaintextLength))
|
|
return DecodingResult();
|
|
|
|
xorbuf(plaintext, ciphertext, cipherKey, plaintextLength);
|
|
return DecodingResult(plaintextLength);
|
|
}
|
|
};
|
|
|
|
//! _
|
|
template <class T, bool DHAES_MODE, class KDF>
|
|
class DL_KeyDerivationAlgorithm_P1363 : public DL_KeyDerivationAlgorithm<T>
|
|
{
|
|
public:
|
|
virtual ~DL_KeyDerivationAlgorithm_P1363() { }
|
|
bool ParameterSupported(const char *name) const {return strcmp(name, Name::KeyDerivationParameters()) == 0;}
|
|
void Derive(const DL_GroupParameters<T> ¶ms, byte *derivedKey, size_t derivedLength, const T &agreedElement, const T &ephemeralPublicKey, const NameValuePairs ¶meters) const
|
|
{
|
|
SecByteBlock agreedSecret;
|
|
if (DHAES_MODE)
|
|
{
|
|
agreedSecret.New(params.GetEncodedElementSize(true) + params.GetEncodedElementSize(false));
|
|
params.EncodeElement(true, ephemeralPublicKey, agreedSecret);
|
|
params.EncodeElement(false, agreedElement, agreedSecret + params.GetEncodedElementSize(true));
|
|
}
|
|
else
|
|
{
|
|
agreedSecret.New(params.GetEncodedElementSize(false));
|
|
params.EncodeElement(false, agreedElement, agreedSecret);
|
|
}
|
|
|
|
ConstByteArrayParameter derivationParameters;
|
|
parameters.GetValue(Name::KeyDerivationParameters(), derivationParameters);
|
|
KDF::DeriveKey(derivedKey, derivedLength, agreedSecret, agreedSecret.size(), derivationParameters.begin(), derivationParameters.size());
|
|
}
|
|
};
|
|
|
|
//! Discrete Log Integrated Encryption Scheme, AKA <a href="http://www.weidai.com/scan-mirror/ca.html#DLIES">DLIES</a>
|
|
template <class COFACTOR_OPTION = NoCofactorMultiplication, bool DHAES_MODE = true>
|
|
struct DLIES
|
|
: public DL_ES<
|
|
DL_CryptoKeys_GFP,
|
|
DL_KeyAgreementAlgorithm_DH<Integer, COFACTOR_OPTION>,
|
|
DL_KeyDerivationAlgorithm_P1363<Integer, DHAES_MODE, P1363_KDF2<SHA1> >,
|
|
DL_EncryptionAlgorithm_Xor<HMAC<SHA1>, DHAES_MODE>,
|
|
DLIES<> >
|
|
{
|
|
static std::string CRYPTOPP_API StaticAlgorithmName() {return "DLIES";} // TODO: fix this after name is standardized
|
|
};
|
|
|
|
NAMESPACE_END
|
|
|
|
#endif
|