3 files changed, 215 insertions, 0 deletions
diff --git a/src/lib/pubkey/dl_algo/dl_algo.cpp b/src/lib/pubkey/dl_algo/dl_algo.cpp
new file mode 100644
index 000000000..92c78ac79
--- /dev/null
+++ b/src/lib/pubkey/dl_algo/dl_algo.cpp
@@ -0,0 +1,91 @@
+/*
+* DL Scheme
+* (C) 1999-2007 Jack Lloyd
+*
+* Distributed under the terms of the Botan license
+*/
+
+#include <botan/dl_algo.h>
+#include <botan/numthry.h>
+#include <botan/workfactor.h>
+#include <botan/der_enc.h>
+#include <botan/ber_dec.h>
+
+namespace Botan {
+
+size_t DL_Scheme_PublicKey::estimated_strength() const
+   {
+   return dl_work_factor(group.get_p().bits());
+   }
+
+AlgorithmIdentifier DL_Scheme_PublicKey::algorithm_identifier() const
+   {
+   return AlgorithmIdentifier(get_oid(),
+                              group.DER_encode(group_format()));
+   }
+
+std::vector<byte> DL_Scheme_PublicKey::x509_subject_public_key() const
+   {
+   return DER_Encoder().encode(y).get_contents_unlocked();
+   }
+
+DL_Scheme_PublicKey::DL_Scheme_PublicKey(const AlgorithmIdentifier& alg_id,
+                                         const secure_vector<byte>& key_bits,
+                                         DL_Group::Format format)
+   {
+   group.BER_decode(alg_id.parameters, format);
+
+   BER_Decoder(key_bits).decode(y);
+   }
+
+secure_vector<byte> DL_Scheme_PrivateKey::pkcs8_private_key() const
+   {
+   return DER_Encoder().encode(x).get_contents();
+   }
+
+DL_Scheme_PrivateKey::DL_Scheme_PrivateKey(const AlgorithmIdentifier& alg_id,
+                                           const secure_vector<byte>& key_bits,
+                                           DL_Group::Format format)
+   {
+   group.BER_decode(alg_id.parameters, format);
+
+   BER_Decoder(key_bits).decode(x);
+   }
+
+/*
+* Check Public DL Parameters
+*/
+bool DL_Scheme_PublicKey::check_key(RandomNumberGenerator& rng,
+                                    bool strong) const
+   {
+   if(y < 2 || y >= group_p())
+      return false;
+   if(!group.verify_group(rng, strong))
+      return false;
+   return true;
+   }
+
+/*
+* Check DL Scheme Private Parameters
+*/
+bool DL_Scheme_PrivateKey::check_key(RandomNumberGenerator& rng,
+                                     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(rng, strong))
+      return false;
+
+   if(!strong)
+      return true;
+
+   if(y != power_mod(g, x, p))
+      return false;
+
+   return true;
+   }
+
+}
diff --git a/src/lib/pubkey/dl_algo/dl_algo.h b/src/lib/pubkey/dl_algo/dl_algo.h
new file mode 100644
index 000000000..abd2acba4
--- /dev/null
+++ b/src/lib/pubkey/dl_algo/dl_algo.h
@@ -0,0 +1,116 @@
+/*
+* DL Scheme
+* (C) 1999-2007 Jack Lloyd
+*
+* Distributed under the terms of the Botan license
+*/
+
+#ifndef BOTAN_DL_ALGO_H__
+#define BOTAN_DL_ALGO_H__
+
+#include <botan/dl_group.h>
+#include <botan/x509_key.h>
+#include <botan/pkcs8.h>
+
+namespace Botan {
+
+/**
+* This class represents discrete logarithm (DL) public keys.
+*/
+class BOTAN_DLL DL_Scheme_PublicKey : public virtual Public_Key
+   {
+   public:
+      bool check_key(RandomNumberGenerator& rng, bool) const;
+
+      AlgorithmIdentifier algorithm_identifier() const;
+
+      std::vector<byte> x509_subject_public_key() const;
+
+      /**
+      * Get the DL domain parameters of this key.
+      * @return DL domain parameters of this key
+      */
+      const DL_Group& get_domain() const { return group; }
+
+      /**
+      * Get the public value y with y = g^x mod p where x is the secret key.
+      */
+      const BigInt& get_y() const { return y; }
+
+      /**
+      * Get the prime p of the underlying DL group.
+      * @return prime p
+      */
+      const BigInt& group_p() const { return group.get_p(); }
+
+      /**
+      * Get the prime q of the underlying DL group.
+      * @return prime q
+      */
+      const BigInt& group_q() const { return group.get_q(); }
+
+      /**
+      * Get the generator g of the underlying DL group.
+      * @return generator g
+      */
+      const BigInt& group_g() const { return group.get_g(); }
+
+      /**
+      * Get the underlying groups encoding format.
+      * @return encoding format
+      */
+      virtual DL_Group::Format group_format() const = 0;
+
+      size_t estimated_strength() const override;
+
+      DL_Scheme_PublicKey(const AlgorithmIdentifier& alg_id,
+                          const secure_vector<byte>& key_bits,
+                          DL_Group::Format group_format);
+
+   protected:
+      DL_Scheme_PublicKey() {}
+
+      /**
+      * The DL public key
+      */
+      BigInt y;
+
+      /**
+      * The DL group
+      */
+      DL_Group group;
+   };
+
+/**
+* This class represents discrete logarithm (DL) private keys.
+*/
+class BOTAN_DLL DL_Scheme_PrivateKey : public virtual DL_Scheme_PublicKey,
+                                       public virtual Private_Key
+   {
+   public:
+      bool check_key(RandomNumberGenerator& rng, bool) const;
+
+      /**
+      * Get the secret key x.
+      * @return secret key
+      */
+      const BigInt& get_x() const { return x; }
+
+      secure_vector<byte> pkcs8_private_key() const;
+
+      DL_Scheme_PrivateKey(const AlgorithmIdentifier& alg_id,
+                           const secure_vector<byte>& key_bits,
+                           DL_Group::Format group_format);
+
+   protected:
+      DL_Scheme_PrivateKey() {}
+
+      /**
+      * The DL private key
+      */
+      BigInt x;
+   };
+
+}
+
+#endif
diff --git a/src/lib/pubkey/dl_algo/info.txt b/src/lib/pubkey/dl_algo/info.txt
new file mode 100644
index 000000000..6f3b3195d
--- /dev/null
+++ b/src/lib/pubkey/dl_algo/info.txt
@@ -0,0 +1,8 @@
+define DL_PUBLIC_KEY_FAMILY 20131128
+
+<requires>
+asn1
+dl_group
+numbertheory
+rng
+</requires>