00001 #ifndef CRYPTOPP_ESIGN_H
00002 #define CRYPTOPP_ESIGN_H
00003
00004
00005
00006
00007
00008
00009 #include "pubkey.h"
00010 #include "integer.h"
00011
00012 NAMESPACE_BEGIN(CryptoPP)
00013
00014
00015 class ESIGNFunction : public TrapdoorFunction, public PublicKey, public ASN1CryptoMaterial
00016 {
00017 typedef ESIGNFunction ThisClass;
00018
00019 public:
00020 void Initialize(const Integer &n, const Integer &e)
00021 {m_n = n; m_e = e;}
00022
00023
00024 void BERDecode(BufferedTransformation &bt);
00025 void DEREncode(BufferedTransformation &bt) const;
00026
00027
00028 bool Validate(RandomNumberGenerator &rng, unsigned int level) const;
00029 bool GetVoidValue(const char *name, const std::type_info &valueType, void *pValue) const;
00030 void AssignFrom(const NameValuePairs &source);
00031
00032
00033 Integer ApplyFunction(const Integer &x) const;
00034 Integer PreimageBound() const {return m_n;}
00035 Integer ImageBound() const {return Integer::Power2(GetK());}
00036
00037
00038 const Integer & GetModulus() const {return m_n;}
00039 const Integer & GetPublicExponent() const {return m_e;}
00040
00041 void SetModulus(const Integer &n) {m_n = n;}
00042 void SetPublicExponent(const Integer &e) {m_e = e;}
00043
00044 protected:
00045 unsigned int GetK() const {return m_n.BitCount()/3-1;}
00046
00047 Integer m_n, m_e;
00048 };
00049
00050
00051 class InvertibleESIGNFunction : public ESIGNFunction, public RandomizedTrapdoorFunctionInverse, public PrivateKey
00052 {
00053 typedef InvertibleESIGNFunction ThisClass;
00054
00055 public:
00056 void Initialize(const Integer &n, const Integer &e, const Integer &p, const Integer &q)
00057 {m_n = n; m_e = e; m_p = p; m_q = q;}
00058
00059 void Initialize(RandomNumberGenerator &rng, unsigned int modulusBits)
00060 {GenerateRandomWithKeySize(rng, modulusBits);}
00061
00062 void BERDecode(BufferedTransformation &bt);
00063 void DEREncode(BufferedTransformation &bt) const;
00064
00065 Integer CalculateRandomizedInverse(RandomNumberGenerator &rng, const Integer &x) const;
00066
00067
00068 bool Validate(RandomNumberGenerator &rng, unsigned int level) const;
00069 bool GetVoidValue(const char *name, const std::type_info &valueType, void *pValue) const;
00070 void AssignFrom(const NameValuePairs &source);
00071
00072 void GenerateRandom(RandomNumberGenerator &rng, const NameValuePairs &alg);
00073
00074 const Integer& GetPrime1() const {return m_p;}
00075 const Integer& GetPrime2() const {return m_q;}
00076
00077 void SetPrime1(const Integer &p) {m_p = p;}
00078 void SetPrime2(const Integer &q) {m_q = q;}
00079
00080 protected:
00081 Integer m_p, m_q;
00082 };
00083
00084
00085 template <class T>
00086 class EMSA5Pad : public PK_DeterministicSignatureMessageEncodingMethod
00087 {
00088 public:
00089 static const char *StaticAlgorithmName() {return "EMSA5";}
00090
00091 void ComputeMessageRepresentative(RandomNumberGenerator &rng,
00092 const byte *recoverableMessage, size_t recoverableMessageLength,
00093 HashTransformation &hash, HashIdentifier hashIdentifier, bool messageEmpty,
00094 byte *representative, size_t representativeBitLength) const
00095 {
00096 SecByteBlock digest(hash.DigestSize());
00097 hash.Final(digest);
00098 size_t representativeByteLength = BitsToBytes(representativeBitLength);
00099 T mgf;
00100 mgf.GenerateAndMask(hash, representative, representativeByteLength, digest, digest.size(), false);
00101 if (representativeBitLength % 8 != 0)
00102 representative[0] = (byte)Crop(representative[0], representativeBitLength % 8);
00103 }
00104 };
00105
00106
00107 struct P1363_EMSA5 : public SignatureStandard
00108 {
00109 typedef EMSA5Pad<P1363_MGF1> SignatureMessageEncodingMethod;
00110 };
00111
00112 struct ESIGN_Keys
00113 {
00114 static std::string StaticAlgorithmName() {return "ESIGN";}
00115 typedef ESIGNFunction PublicKey;
00116 typedef InvertibleESIGNFunction PrivateKey;
00117 };
00118
00119
00120 template <class H, class STANDARD = P1363_EMSA5>
00121 struct ESIGN : public TF_SS<STANDARD, H, ESIGN_Keys>
00122 {
00123 };
00124
00125 NAMESPACE_END
00126
00127 #endif