/************************************************* * DL Scheme Source File * * (C) 1999-2007 Jack Lloyd * *************************************************/ #include #include #include #include namespace Botan { /************************************************* * Return the X.509 public key encoder * *************************************************/ X509_Encoder* DL_Scheme_PublicKey::x509_encoder() const { class DL_Scheme_Encoder : public X509_Encoder { public: AlgorithmIdentifier alg_id() const { MemoryVector group = key->group.DER_encode(key->group_format()); return AlgorithmIdentifier(key->get_oid(), group); } MemoryVector key_bits() const { return DER_Encoder().encode(key->y).get_contents(); } DL_Scheme_Encoder(const DL_Scheme_PublicKey* k) : key(k) {} private: const DL_Scheme_PublicKey* key; }; return new DL_Scheme_Encoder(this); } /************************************************* * Return the X.509 public key decoder * *************************************************/ X509_Decoder* DL_Scheme_PublicKey::x509_decoder() { class DL_Scheme_Decoder : public X509_Decoder { public: void alg_id(const AlgorithmIdentifier& alg_id) { DataSource_Memory source(alg_id.parameters); key->group.BER_decode(source, key->group_format()); } void key_bits(const MemoryRegion& bits) { BER_Decoder(bits).decode(key->y); key->X509_load_hook(); } DL_Scheme_Decoder(DL_Scheme_PublicKey* k) : key(k) {} private: DL_Scheme_PublicKey* key; }; return new DL_Scheme_Decoder(this); } /************************************************* * Return the PKCS #8 private key encoder * *************************************************/ PKCS8_Encoder* DL_Scheme_PrivateKey::pkcs8_encoder() const { class DL_Scheme_Encoder : public PKCS8_Encoder { public: AlgorithmIdentifier alg_id() const { MemoryVector group = key->group.DER_encode(key->group_format()); return AlgorithmIdentifier(key->get_oid(), group); } MemoryVector key_bits() const { return DER_Encoder().encode(key->x).get_contents(); } DL_Scheme_Encoder(const DL_Scheme_PrivateKey* k) : key(k) {} private: const DL_Scheme_PrivateKey* key; }; return new DL_Scheme_Encoder(this); } /************************************************* * Return the PKCS #8 private key decoder * *************************************************/ PKCS8_Decoder* DL_Scheme_PrivateKey::pkcs8_decoder() { class DL_Scheme_Decoder : public PKCS8_Decoder { public: void alg_id(const AlgorithmIdentifier& alg_id) { DataSource_Memory source(alg_id.parameters); key->group.BER_decode(source, key->group_format()); } void key_bits(const MemoryRegion& bits) { BER_Decoder(bits).decode(key->x); key->PKCS8_load_hook(); } DL_Scheme_Decoder(DL_Scheme_PrivateKey* k) : key(k) {} private: DL_Scheme_PrivateKey* key; }; return new DL_Scheme_Decoder(this); } /************************************************* * Check Public DL Parameters * *************************************************/ bool DL_Scheme_PublicKey::check_key(bool strong) const { if(y < 2 || y >= group_p()) return false; if(!group.verify_group(strong)) return false; return true; } /************************************************* * Check DL Scheme Private Parameters * *************************************************/ bool DL_Scheme_PrivateKey::check_key(bool strong) const { const BigInt& p = group_p(); const BigInt& g = group_g(); if(y < 2 || y >= p || x < 2 || x >= p) return false; if(!group.verify_group(strong)) return false; if(!strong) return true; if(y != power_mod(g, x, p)) return false; return true; } }