Remove Algo_Registry usage from public key code.

Instead the key types exposes operations like `create_encryption_op`
which will return the relevant operation if the algorithm supports it.

Changes pubkey.h interface, now RNG is passed at init time.
Blinder previous created its own RNG, now it takes it from app.

2 files changed, 25 insertions, 15 deletions

diff --git a/src/lib/pubkey/dh/dh.cpp b/src/lib/pubkey/dh/dh.cpp
index 8ed79aa3d..3cd47c581 100644
--- a/src/lib/pubkey/dh/dh.cpp
+++ b/src/lib/pubkey/dh/dh.cpp
@@ -1,12 +1,12 @@
 /*
 * Diffie-Hellman
-* (C) 1999-2007 Jack Lloyd
+* (C) 1999-2007,2016 Jack Lloyd
 *
 * Botan is released under the Simplified BSD License (see license.txt)
 */
 
-#include <botan/internal/pk_utils.h>
 #include <botan/dh.h>
+#include <botan/internal/pk_ops_impl.h>
 #include <botan/workfactor.h>
 #include <botan/pow_mod.h>
 #include <botan/blinding.h>
@@ -41,7 +41,7 @@ DH_PrivateKey::DH_PrivateKey(RandomNumberGenerator& rng,
    m_group = grp;
    m_x = x_arg;
 
-   if(m_x == 0)
+   if(generate)
       {
       const BigInt& p = group_p();
       m_x.randomize(rng, dl_exponent_size(p.bits()));
@@ -93,7 +93,16 @@ class DH_KA_Operation : public PK_Ops::Key_Agreement_with_KDF
    {
    public:
       typedef DH_PrivateKey Key_Type;
-      DH_KA_Operation(const DH_PrivateKey& key, const std::string& kdf);
+
+      DH_KA_Operation(const DH_PrivateKey& key, const std::string& kdf, RandomNumberGenerator& rng) :
+         PK_Ops::Key_Agreement_with_KDF(kdf),
+         m_p(key.group_p()),
+         m_powermod_x_p(key.get_x(), m_p),
+         m_blinder(m_p,
+                   rng,
+                   [](const BigInt& k) { return k; },
+                   [this](const BigInt& k) { return m_powermod_x_p(inverse_mod(k, m_p)); })
+         {}
 
       secure_vector<byte> raw_agree(const byte w[], size_t w_len) override;
    private:
@@ -103,16 +112,6 @@ class DH_KA_Operation : public PK_Ops::Key_Agreement_with_KDF
       Blinder m_blinder;
    };
 
-DH_KA_Operation::DH_KA_Operation(const DH_PrivateKey& dh, const std::string& kdf) :
-   PK_Ops::Key_Agreement_with_KDF(kdf),
-   m_p(dh.group_p()),
-   m_powermod_x_p(dh.get_x(), m_p),
-   m_blinder(m_p,
-             [](const BigInt& k) { return k; },
-             [this](const BigInt& k) { return m_powermod_x_p(inverse_mod(k, m_p)); })
-   {
-   }
-
 secure_vector<byte> DH_KA_Operation::raw_agree(const byte w[], size_t w_len)
    {
    BigInt input = BigInt::decode(w, w_len);
@@ -127,6 +126,12 @@ secure_vector<byte> DH_KA_Operation::raw_agree(const byte w[], size_t w_len)
 
 }
 
-BOTAN_REGISTER_PK_KEY_AGREE_OP("DH", DH_KA_Operation);
+std::unique_ptr<PK_Ops::Key_Agreement>
+DH_PrivateKey::create_key_agreement_op(RandomNumberGenerator& rng,
+                                       const std::string& params,
+                                       const std::string& /*provider*/) const
+   {
+   return std::unique_ptr<PK_Ops::Key_Agreement>(new DH_KA_Operation(*this, params, rng));
+   }
 
 }
diff --git a/src/lib/pubkey/dh/dh.h b/src/lib/pubkey/dh/dh.h
index 9911453fb..d15bc5eb3 100644
--- a/src/lib/pubkey/dh/dh.h
+++ b/src/lib/pubkey/dh/dh.h
@@ -67,6 +67,11 @@ class BOTAN_DLL DH_PrivateKey : public DH_PublicKey,
       */
       DH_PrivateKey(RandomNumberGenerator& rng, const DL_Group& grp,
                     const BigInt& x = 0);
+
+      std::unique_ptr<PK_Ops::Key_Agreement>
+         create_key_agreement_op(RandomNumberGenerator& rng,
+                                 const std::string& params,
+                                 const std::string& provider) const override;
    };
 
 }