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# eccrypto.h

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    00001 #ifndef CRYPTOPP_ECCRYPTO_H
    00002 #define CRYPTOPP_ECCRYPTO_H
    00003
    00004 /*! \file
    00005 */
    00006
    00007 #include "pubkey.h"
    00008 #include "integer.h"
    00009 #include "asn.h"
    00010 #include "hmac.h"
    00011 #include "sha.h"
    00012 #include "gfpcrypt.h"
    00013 #include "dh.h"
    00014 #include "mqv.h"
    00015 #include "ecp.h"
    00016 #include "ec2n.h"
    00017
    00018 NAMESPACE_BEGIN(CryptoPP)
    00019
    00020 //! Elliptic Curve Parameters
    00021 /*! This class corresponds to the ASN.1 sequence of the same name
    00022     in ANSI X9.62 (also SEC 1).
    00023 */
    00024 template <class EC>
    00025 class DL_GroupParameters_EC : public DL_GroupParametersImpl<EcPrecomputation<EC> >
    00026 {
    00027         typedef DL_GroupParameters_EC<EC> ThisClass;
    00028
    00029 public:
    00030         typedef EC EllipticCurve;
    00031         typedef typename EllipticCurve::Point Point;
    00032         typedef Point Element;
    00033         typedef IncompatibleCofactorMultiplication DefaultCofactorOption;
    00034
    00035         DL_GroupParameters_EC() : m_compress(false), m_encodeAsOID(false) {}
    00036         DL_GroupParameters_EC(const OID &oid)
    00037                 : m_compress(false), m_encodeAsOID(false) {Initialize(oid);}
    00038         DL_GroupParameters_EC(const EllipticCurve &ec, const Point &G, const Integer &n, const Integer &k = Integer::Zero())
    00039                 : m_compress(false), m_encodeAsOID(false) {Initialize(ec, G, n, k);}
    00040         DL_GroupParameters_EC(BufferedTransformation &bt)
    00041                 : m_compress(false), m_encodeAsOID(false) {BERDecode(bt);}
    00042
    00043         void Initialize(const EllipticCurve &ec, const Point &G, const Integer &n, const Integer &k = Integer::Zero())
    00044         {
    00045                 this->m_groupPrecomputation.SetCurve(ec);
    00046                 SetSubgroupGenerator(G);
    00047                 m_n = n;
    00048                 m_k = k;
    00049         }
    00050         void Initialize(const OID &oid);
    00051
    00052         // NameValuePairs
    00053         bool GetVoidValue(const char *name, const std::type_info &valueType, void *pValue) const;
    00054         void AssignFrom(const NameValuePairs &source);
    00055
    00056         // GeneratibleCryptoMaterial interface
    00057         //! this implementation doesn't actually generate a curve, it just initializes the parameters with existing values
    00058         /*! parameters: (Curve, SubgroupGenerator, SubgroupOrder, Cofactor (optional)), or (GroupOID) */
    00059         void GenerateRandom(RandomNumberGenerator &rng, const NameValuePairs &alg);
    00060
    00061         // DL_GroupParameters
    00062         const DL_FixedBasePrecomputation<Element> & GetBasePrecomputation() const {return this->m_gpc;}
    00063         DL_FixedBasePrecomputation<Element> & AccessBasePrecomputation() {return this->m_gpc;}
    00064         const Integer & GetSubgroupOrder() const {return m_n;}
    00065         Integer GetCofactor() const;
    00066         bool ValidateGroup(RandomNumberGenerator &rng, unsigned int level) const;
    00067         bool ValidateElement(unsigned int level, const Element &element, const DL_FixedBasePrecomputation<Element> *precomp) const;
    00068         bool FastSubgroupCheckAvailable() const {return false;}
    00069         void EncodeElement(bool reversible, const Element &element, byte *encoded) const
    00070         {
    00071                 if (reversible)
    00072                         GetCurve().EncodePoint(encoded, element, m_compress);
    00073                 else
    00074                         element.x.Encode(encoded, GetEncodedElementSize(false));
    00075         }
    00076         unsigned int GetEncodedElementSize(bool reversible) const
    00077         {
    00078                 if (reversible)
    00079                         return GetCurve().EncodedPointSize(m_compress);
    00080                 else
    00081                         return GetCurve().GetField().MaxElementByteLength();
    00082         }
    00083         Element DecodeElement(const byte *encoded, bool checkForGroupMembership) const
    00084         {
    00085                 Point result;
    00086                 if (!GetCurve().DecodePoint(result, encoded, GetEncodedElementSize(true)))
    00087                         throw DL_BadElement();
    00088                 if (checkForGroupMembership && !ValidateElement(1, result, NULL))
    00089                         throw DL_BadElement();
    00090                 return result;
    00091         }
    00092         Integer ConvertElementToInteger(const Element &element) const;
    00093         Integer GetMaxExponent() const {return GetSubgroupOrder()-1;}
    00094         bool IsIdentity(const Element &element) const {return element.identity;}
    00095         void SimultaneousExponentiate(Element *results, const Element &base, const Integer *exponents, unsigned int exponentsCount) const;
    00096         static std::string CRYPTOPP_API StaticAlgorithmNamePrefix() {return "EC";}
    00097
    00098         // ASN1Key
    00099         OID GetAlgorithmID() const;
    00100
    00101         // used by MQV
    00102         Element MultiplyElements(const Element &a, const Element &b) const;
    00103         Element CascadeExponentiate(const Element &element1, const Integer &exponent1, const Element &element2, const Integer &exponent2) const;
    00104
    00105         // non-inherited
    00106
    00107         // enumerate OIDs for recommended parameters, use OID() to get first one
    00108         static OID CRYPTOPP_API GetNextRecommendedParametersOID(const OID &oid);
    00109
    00110         void BERDecode(BufferedTransformation &bt);
    00111         void DEREncode(BufferedTransformation &bt) const;
    00112
    00113         void SetPointCompression(bool compress) {m_compress = compress;}
    00114         bool GetPointCompression() const {return m_compress;}
    00115
    00116         void SetEncodeAsOID(bool encodeAsOID) {m_encodeAsOID = encodeAsOID;}
    00117         bool GetEncodeAsOID() const {return m_encodeAsOID;}
    00118
    00119         const EllipticCurve& GetCurve() const {return this->m_groupPrecomputation.GetCurve();}
    00120
    00121         bool operator==(const ThisClass &rhs) const
    00122                 {return this->m_groupPrecomputation.GetCurve() == rhs.m_groupPrecomputation.GetCurve() && this->m_gpc.GetBase(this->m_groupPrecomputation) == rhs.m_gpc.GetBase(rhs.m_groupPrecomputation);}
    00123
    00124 #ifdef CRYPTOPP_MAINTAIN_BACKWARDS_COMPATIBILITY
    00125         const Point& GetBasePoint() const {return GetSubgroupGenerator();}
    00126         const Integer& GetBasePointOrder() const {return GetSubgroupOrder();}
    00127         void LoadRecommendedParameters(const OID &oid) {Initialize(oid);}
    00128 #endif
    00129
    00130 protected:
    00131         unsigned int FieldElementLength() const {return GetCurve().GetField().MaxElementByteLength();}
    00132         unsigned int ExponentLength() const {return m_n.ByteCount();}
    00133
    00134         OID m_oid;                      // set if parameters loaded from a recommended curve
    00135         Integer m_n;            // order of base point
    00136         bool m_compress, m_encodeAsOID;
    00137         mutable Integer m_k;            // cofactor
    00138 };
    00139
    00140 //! EC public key
    00141 template <class EC>
    00142 class DL_PublicKey_EC : public DL_PublicKeyImpl<DL_GroupParameters_EC<EC> >
    00143 {
    00144 public:
    00145         typedef typename EC::Point Element;
    00146
    00147         void Initialize(const DL_GroupParameters_EC<EC> &params, const Element &Q)
    00148                 {this->AccessGroupParameters() = params; SetPublicElement(Q);}
    00149         void Initialize(const EC &ec, const Element &G, const Integer &n, const Element &Q)
    00150                 {this->AccessGroupParameters().Initialize(ec, G, n); SetPublicElement(Q);}
    00151
    00152         // X509PublicKey
    00153         void BERDecodeKey2(BufferedTransformation &bt, bool parametersPresent, size_t size);
    00154         void DEREncodeKey(BufferedTransformation &bt) const;
    00155 };
    00156
    00157 //! EC private key
    00158 template <class EC>
    00159 class DL_PrivateKey_EC : public DL_PrivateKeyImpl<DL_GroupParameters_EC<EC> >
    00160 {
    00161 public:
    00162         typedef typename EC::Point Element;
    00163
    00164         void Initialize(const DL_GroupParameters_EC<EC> &params, const Integer &x)
    00165                 {this->AccessGroupParameters() = params; this->SetPrivateExponent(x);}
    00166         void Initialize(const EC &ec, const Element &G, const Integer &n, const Integer &x)
    00167                 {this->AccessGroupParameters().Initialize(ec, G, n); this->SetPrivateExponent(x);}
    00168         void Initialize(RandomNumberGenerator &rng, const DL_GroupParameters_EC<EC> &params)
    00169                 {GenerateRandom(rng, params);}
    00170         void Initialize(RandomNumberGenerator &rng, const EC &ec, const Element &G, const Integer &n)
    00171                 {GenerateRandom(rng, DL_GroupParameters_EC<EC>(ec, G, n));}
    00172
    00173         // PKCS8PrivateKey
    00174         void BERDecodeKey2(BufferedTransformation &bt, bool parametersPresent, size_t size);
    00175         void DEREncodeKey(BufferedTransformation &bt) const;
    00176 };
    00177
    00178 //! Elliptic Curve Diffie-Hellman, AKA <a href="http://www.weidai.com/scan-mirror/ka.html#ECDH">ECDH</a>
    00179 template <class EC, class COFACTOR_OPTION = CPP_TYPENAME DL_GroupParameters_EC<EC>::DefaultCofactorOption>
    00180 struct ECDH
    00181 {
    00182         typedef DH_Domain<DL_GroupParameters_EC<EC>, COFACTOR_OPTION> Domain;
    00183 };
    00184
    00185 /// Elliptic Curve Menezes-Qu-Vanstone, AKA <a href="http://www.weidai.com/scan-mirror/ka.html#ECMQV">ECMQV</a>
    00186 template <class EC, class COFACTOR_OPTION = CPP_TYPENAME DL_GroupParameters_EC<EC>::DefaultCofactorOption>
    00187 struct ECMQV
    00188 {
    00189         typedef MQV_Domain<DL_GroupParameters_EC<EC>, COFACTOR_OPTION> Domain;
    00190 };
    00191
    00192 //! EC keys
    00193 template <class EC>
    00194 struct DL_Keys_EC
    00195 {
    00196         typedef DL_PublicKey_EC<EC> PublicKey;
    00197         typedef DL_PrivateKey_EC<EC> PrivateKey;
    00198 };
    00199
    00200 template <class EC, class H = SHA>
    00201 struct ECDSA;
    00202
    00203 //! ECDSA keys
    00204 template <class EC>
    00205 struct DL_Keys_ECDSA
    00206 {
    00207         typedef DL_PublicKey_EC<EC> PublicKey;
    00208         typedef DL_PrivateKey_WithSignaturePairwiseConsistencyTest<DL_PrivateKey_EC<EC>, ECDSA<EC> > PrivateKey;
    00209 };
    00210
    00211 //! ECDSA algorithm
    00212 template <class EC>
    00213 class DL_Algorithm_ECDSA : public DL_Algorithm_GDSA<typename EC::Point>
    00214 {
    00215 public:
    00216         static const char * CRYPTOPP_API StaticAlgorithmName() {return "ECDSA";}
    00217 };
    00218
    00219 //! ECNR algorithm
    00220 template <class EC>
    00221 class DL_Algorithm_ECNR : public DL_Algorithm_NR<typename EC::Point>
    00222 {
    00223 public:
    00224         static const char * CRYPTOPP_API StaticAlgorithmName() {return "ECNR";}
    00225 };
    00226
    00227 //! <a href="http://www.weidai.com/scan-mirror/sig.html#ECDSA">ECDSA</a>
    00228 template <class EC, class H>
    00229 struct ECDSA : public DL_SS<DL_Keys_ECDSA<EC>, DL_Algorithm_ECDSA<EC>, DL_SignatureMessageEncodingMethod_DSA, H>
    00230 {
    00231 };
    00232
    00233 //! ECNR
    00234 template <class EC, class H = SHA>
    00235 struct ECNR : public DL_SS<DL_Keys_EC<EC>, DL_Algorithm_ECNR<EC>, DL_SignatureMessageEncodingMethod_NR, H>
    00236 {
    00237 };
    00238
    00239 //! Elliptic Curve Integrated Encryption Scheme, AKA <a href="http://www.weidai.com/scan-mirror/ca.html#ECIES">ECIES</a>
    00240 /*! Default to (NoCofactorMultiplication and DHAES_MODE = false) for compatibilty with SEC1 and Crypto++ 4.2.
    00241         The combination of (IncompatibleCofactorMultiplication and DHAES_MODE = true) is recommended for best
    00242         efficiency and security. */
    00243 template <class EC, class COFACTOR_OPTION = NoCofactorMultiplication, bool DHAES_MODE = false>
    00244 struct ECIES
    00245         : public DL_ES<
    00246                 DL_Keys_EC<EC>,
    00247                 DL_KeyAgreementAlgorithm_DH<typename EC::Point, COFACTOR_OPTION>,
    00248                 DL_KeyDerivationAlgorithm_P1363<typename EC::Point, DHAES_MODE, P1363_KDF2<SHA1> >,
    00249                 DL_EncryptionAlgorithm_Xor<HMAC<SHA1>, DHAES_MODE>,
    00250                 ECIES<EC> >
    00251 {
    00252         static std::string CRYPTOPP_API StaticAlgorithmName() {return "ECIES";} // TODO: fix this after name is standardized
    00253 };
    00254
    00255 NAMESPACE_END
    00256
    00257 #ifdef CRYPTOPP_MANUALLY_INSTANTIATE_TEMPLATES
    00258 #include "eccrypto.cpp"
    00259 #endif
    00260
    00261 NAMESPACE_BEGIN(CryptoPP)
    00262
    00263 CRYPTOPP_DLL_TEMPLATE_CLASS DL_GroupParameters_EC<ECP>;
    00264 CRYPTOPP_DLL_TEMPLATE_CLASS DL_GroupParameters_EC<EC2N>;
    00265 CRYPTOPP_DLL_TEMPLATE_CLASS DL_PublicKeyImpl<DL_GroupParameters_EC<ECP> >;
    00266 CRYPTOPP_DLL_TEMPLATE_CLASS DL_PublicKeyImpl<DL_GroupParameters_EC<EC2N> >;
    00267 CRYPTOPP_DLL_TEMPLATE_CLASS DL_PublicKey_EC<ECP>;
    00268 CRYPTOPP_DLL_TEMPLATE_CLASS DL_PublicKey_EC<EC2N>;
    00269 CRYPTOPP_DLL_TEMPLATE_CLASS DL_PrivateKeyImpl<DL_GroupParameters_EC<ECP> >;
    00270 CRYPTOPP_DLL_TEMPLATE_CLASS DL_PrivateKeyImpl<DL_GroupParameters_EC<EC2N> >;
    00271 CRYPTOPP_DLL_TEMPLATE_CLASS DL_PrivateKey_EC<ECP>;
    00272 CRYPTOPP_DLL_TEMPLATE_CLASS DL_PrivateKey_EC<EC2N>;
    00273 CRYPTOPP_DLL_TEMPLATE_CLASS DL_Algorithm_GDSA<ECP::Point>;
    00274 CRYPTOPP_DLL_TEMPLATE_CLASS DL_Algorithm_GDSA<EC2N::Point>;
    00275 CRYPTOPP_DLL_TEMPLATE_CLASS DL_PrivateKey_WithSignaturePairwiseConsistencyTest<DL_PrivateKey_EC<ECP>, ECDSA<ECP> >;
    00276 CRYPTOPP_DLL_TEMPLATE_CLASS DL_PrivateKey_WithSignaturePairwiseConsistencyTest<DL_PrivateKey_EC<EC2N>, ECDSA<EC2N> >;
    00277
    00278 NAMESPACE_END
    00279
    00280 #endif