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authorlloyd <[email protected]>2014-01-10 03:41:59 +0000
committerlloyd <[email protected]>2014-01-10 03:41:59 +0000
commit6894dca64c04936d07048c0e8cbf7e25858548c3 (patch)
tree5d572bfde9fe667dab14e3f04b5285a85d8acd95 /src/lib/pubkey/elgamal/elgamal.h
parent9efa3be92442afb3d0b69890a36c7f122df18eda (diff)
Move lib into src
Diffstat (limited to 'src/lib/pubkey/elgamal/elgamal.h')
-rw-r--r--src/lib/pubkey/elgamal/elgamal.h96
1 files changed, 96 insertions, 0 deletions
diff --git a/src/lib/pubkey/elgamal/elgamal.h b/src/lib/pubkey/elgamal/elgamal.h
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index 000000000..9566bcca6
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+++ b/src/lib/pubkey/elgamal/elgamal.h
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+/*
+* ElGamal
+* (C) 1999-2007 Jack Lloyd
+*
+* Distributed under the terms of the Botan license
+*/
+
+#ifndef BOTAN_ELGAMAL_H__
+#define BOTAN_ELGAMAL_H__
+
+#include <botan/dl_algo.h>
+#include <botan/numthry.h>
+#include <botan/reducer.h>
+#include <botan/blinding.h>
+#include <botan/pk_ops.h>
+
+namespace Botan {
+
+/**
+* ElGamal Public Key
+*/
+class BOTAN_DLL ElGamal_PublicKey : public virtual DL_Scheme_PublicKey
+ {
+ public:
+ std::string algo_name() const { return "ElGamal"; }
+ DL_Group::Format group_format() const { return DL_Group::ANSI_X9_42; }
+
+ size_t max_input_bits() const { return (group_p().bits() - 1); }
+
+ ElGamal_PublicKey(const AlgorithmIdentifier& alg_id,
+ const secure_vector<byte>& key_bits) :
+ DL_Scheme_PublicKey(alg_id, key_bits, DL_Group::ANSI_X9_42)
+ {}
+
+ ElGamal_PublicKey(const DL_Group& group, const BigInt& y);
+ protected:
+ ElGamal_PublicKey() {}
+ };
+
+/**
+* ElGamal Private Key
+*/
+class BOTAN_DLL ElGamal_PrivateKey : public ElGamal_PublicKey,
+ public virtual DL_Scheme_PrivateKey
+ {
+ public:
+ bool check_key(RandomNumberGenerator& rng, bool) const;
+
+ ElGamal_PrivateKey(const AlgorithmIdentifier& alg_id,
+ const secure_vector<byte>& key_bits,
+ RandomNumberGenerator& rng);
+
+ ElGamal_PrivateKey(RandomNumberGenerator& rng,
+ const DL_Group& group,
+ const BigInt& priv_key = 0);
+ };
+
+/**
+* ElGamal encryption operation
+*/
+class BOTAN_DLL ElGamal_Encryption_Operation : public PK_Ops::Encryption
+ {
+ public:
+ size_t max_input_bits() const { return mod_p.get_modulus().bits() - 1; }
+
+ ElGamal_Encryption_Operation(const ElGamal_PublicKey& key);
+
+ secure_vector<byte> encrypt(const byte msg[], size_t msg_len,
+ RandomNumberGenerator& rng);
+
+ private:
+ Fixed_Base_Power_Mod powermod_g_p, powermod_y_p;
+ Modular_Reducer mod_p;
+ };
+
+/**
+* ElGamal decryption operation
+*/
+class BOTAN_DLL ElGamal_Decryption_Operation : public PK_Ops::Decryption
+ {
+ public:
+ size_t max_input_bits() const { return mod_p.get_modulus().bits() - 1; }
+
+ ElGamal_Decryption_Operation(const ElGamal_PrivateKey& key,
+ RandomNumberGenerator& rng);
+
+ secure_vector<byte> decrypt(const byte msg[], size_t msg_len);
+ private:
+ Fixed_Exponent_Power_Mod powermod_x_p;
+ Modular_Reducer mod_p;
+ Blinder blinder;
+ };
+
+}
+
+#endif