3 files changed, 185 insertions, 0 deletions
diff --git a/src/engine/dyn_engine/dyn_engine.cpp b/src/engine/dyn_engine/dyn_engine.cpp
new file mode 100644
index 000000000..2dc76d7d6
--- /dev/null
+++ b/src/engine/dyn_engine/dyn_engine.cpp
@@ -0,0 +1,67 @@
+/**
+* Dynamically Loaded Engine
+* (C) 2010 Jack Lloyd
+*
+* Distributed under the terms of the Botan license
+*/
+
+#include <botan/dyn_engine.h>
+#include <botan/internal/dyn_load.h>
+
+namespace Botan {
+
+namespace {
+
+extern "C" {
+   typedef Engine* (*creator_function)(void);
+   typedef void (*destructor_function)(Engine*);
+}
+
+}
+
+Dynamically_Loaded_Engine::Dynamically_Loaded_Engine(
+   const std::string& library_path) :
+   engine(0)
+   {
+   lib = new Dynamically_Loaded_Library(library_path);
+
+   try
+      {
+      creator_function creator = lib->resolve<creator_function>("create_engine");
+
+      engine = creator();
+
+      if(!engine)
+         throw std::runtime_error("Creator function in " + library_path + " failed");
+      }
+   catch(...)
+      {
+      delete lib;
+      lib = 0;
+      throw;
+      }
+   }
+
+Dynamically_Loaded_Engine::~Dynamically_Loaded_Engine()
+   {
+   if(lib && engine)
+      {
+      try
+         {
+         destructor_function destroy =
+            lib->resolve<destructor_function>("destroy_engine");
+         destroy(engine);
+         }
+      catch(...)
+         {
+         delete lib;
+         lib = 0;
+         throw;
+         }
+      }
+
+   if(lib)
+      delete lib;
+   }
+
+}
diff --git a/src/engine/dyn_engine/dyn_engine.h b/src/engine/dyn_engine/dyn_engine.h
new file mode 100644
index 000000000..46752f5a9
--- /dev/null
+++ b/src/engine/dyn_engine/dyn_engine.h
@@ -0,0 +1,100 @@
+/**
+* Dynamically Loaded Engine
+* (C) 2010 Jack Lloyd
+*
+* Distributed under the terms of the Botan license
+*/
+
+#include <botan/engine.h>
+
+namespace Botan {
+
+/**
+* Dynamically_Loaded_Engine just proxies the requests to the underlying
+* Engine object, and handles load/unload details
+*/
+class BOTAN_DLL Dynamically_Loaded_Engine : public Engine
+   {
+   public:
+      /**
+      * @param lib_path full pathname to DLL to load
+      */
+      Dynamically_Loaded_Engine(const std::string& lib_path);
+
+      ~Dynamically_Loaded_Engine();
+
+      std::string provider_name() const { return engine->provider_name(); }
+
+      BlockCipher* find_block_cipher(const SCAN_Name& algo_spec,
+                                     Algorithm_Factory& af) const
+         {
+         return engine->find_block_cipher(algo_spec, af);
+         }
+
+      StreamCipher* find_stream_cipher(const SCAN_Name& algo_spec,
+                                       Algorithm_Factory& af) const
+         {
+         return engine->find_stream_cipher(algo_spec, af);
+         }
+
+      HashFunction* find_hash(const SCAN_Name& algo_spec,
+                              Algorithm_Factory& af) const
+         {
+         return engine->find_hash(algo_spec, af);
+         }
+
+      MessageAuthenticationCode* find_mac(const SCAN_Name& algo_spec,
+                                          Algorithm_Factory& af) const
+         {
+         return engine->find_mac(algo_spec, af);
+         }
+
+      Modular_Exponentiator* mod_exp(const BigInt& n,
+                                     Power_Mod::Usage_Hints hints) const
+         {
+         return engine->mod_exp(n, hints);
+         }
+
+      Keyed_Filter* get_cipher(const std::string& algo_spec,
+                               Cipher_Dir dir,
+                               Algorithm_Factory& af)
+         {
+         return engine->get_cipher(algo_spec, dir, af);
+         }
+
+      PK_Ops::Key_Agreement*
+         get_key_agreement_op(const Private_Key& key) const
+         {
+         return engine->get_key_agreement_op(key);
+         }
+
+      PK_Ops::Signature*
+         get_signature_op(const Private_Key& key) const
+         {
+         return engine->get_signature_op(key);
+         }
+
+      PK_Ops::Verification*
+         get_verify_op(const Public_Key& key) const
+         {
+         return engine->get_verify_op(key);
+         }
+
+      PK_Ops::Encryption*
+         get_encryption_op(const Public_Key& key) const
+         {
+         return engine->get_encryption_op(key);
+         }
+
+      PK_Ops::Decryption*
+         get_decryption_op(const Private_Key& key) const
+         {
+         return engine->get_decryption_op(key);
+         }
+
+   private:
+      class Dynamically_Loaded_Library* lib;
+      Engine* engine;
+   };
+
+}
diff --git a/src/engine/dyn_engine/info.txt b/src/engine/dyn_engine/info.txt
new file mode 100644
index 000000000..469583522
--- /dev/null
+++ b/src/engine/dyn_engine/info.txt
@@ -0,0 +1,18 @@
+define DYNAMICALLY_LOADED_ENGINE
+
+<header:public>
+dyn_engine.h
+</header:public>
+
+<source>
+dyn_engine.cpp
+</source>
+
+<requires>
+engine
+dyn_load
+</requires>
+
+<libs>
+linux -> dl
+</libs>