Split Diffie-Hellman off almost completely, such that nearly none of

it builds if it is disabled.

Current deficiency: due to #if defined(BLAH) in the engine code,
Botan will not be binary compat across different configurations b/c
the vtable will change size.

Move some source from core/ to core/libstate where it belonged (engine stuff)

7 files changed, 35 insertions, 86 deletions

diff --git a/src/core/info.txt b/src/core/info.txt
index 9331d56dd..6c031d36f 100644
--- a/src/core/info.txt
+++ b/src/core/info.txt
@@ -21,10 +21,8 @@ base.h
 botan.h
 data_src.cpp
 data_src.h
-def_powm.cpp
 defalloc.cpp
 defalloc.h
-eng_def.h
 enums.h
 exceptn.cpp
 exceptn.h
diff --git a/src/core/def_powm.cpp b/src/core/libstate/def_powm.cpp
index a28438f5b..a28438f5b 100644
--- a/src/core/def_powm.cpp
+++ b/src/core/libstate/def_powm.cpp
diff --git a/src/core/libstate/eng_base.cpp b/src/core/libstate/eng_base.cpp
index a296a2762..aaaf46723 100644
--- a/src/core/libstate/eng_base.cpp
+++ b/src/core/libstate/eng_base.cpp
@@ -64,82 +64,6 @@ class Algorithm_Cache_Impl : public Engine::Algorithm_Cache<T>
 }
 
 /*************************************************
-* Basic No-Op Engine Implementation              *
-*************************************************/
-IF_Operation* Engine::if_op(const BigInt&, const BigInt&, const BigInt&,
-                            const BigInt&, const BigInt&, const BigInt&,
-                            const BigInt&, const BigInt&) const
-   {
-   return 0;
-   }
-
-/*************************************************
-* Basic No-Op Engine Implementation              *
-*************************************************/
-DSA_Operation* Engine::dsa_op(const DL_Group&, const BigInt&,
-                              const BigInt&) const
-   {
-   return 0;
-   }
-
-/*************************************************
-* Basic No-Op Engine Implementation              *
-*************************************************/
-NR_Operation* Engine::nr_op(const DL_Group&, const BigInt&,
-                            const BigInt&) const
-   {
-   return 0;
-   }
-
-/*************************************************
-* Basic No-Op Engine Implementation              *
-*************************************************/
-ELG_Operation* Engine::elg_op(const DL_Group&, const BigInt&,
-                              const BigInt&) const
-   {
-   return 0;
-   }
-
-/*************************************************
-* Basic No-Op Engine Implementation              *
-*************************************************/
-DH_Operation* Engine::dh_op(const DL_Group&, const BigInt&) const
-   {
-   return 0;
-   }
-
-#if defined(BOTAN_HAS_ECDSA)
-/*************************************************
-* Basic No-Op Engine Implementation              *
-*************************************************/
-ECDSA_Operation* Engine::ecdsa_op(const EC_Domain_Params&,
-                                  const BigInt&,
-                                  const PointGFp&) const
-   {
-   return 0;
-   }
-
-/*************************************************
-* Basic No-Op Engine Implementation              *
-*************************************************/
-ECKAEG_Operation* Engine::eckaeg_op(const EC_Domain_Params&,
-                                    const BigInt&,
-                                    const PointGFp&) const
-   {
-   return 0;
-   }
-#endif
-
-/*************************************************
-* Basic No-Op Engine Implementation              *
-*************************************************/
-Modular_Exponentiator* Engine::mod_exp(const BigInt&,
-                                       Power_Mod::Usage_Hints) const
-   {
-   return 0;
-   }
-
-/*************************************************
 * Acquire a BlockCipher                          *
 *************************************************/
 const BlockCipher* Engine::block_cipher(const std::string& name) const
diff --git a/src/core/eng_def.h b/src/core/libstate/eng_def.h
index 95f1fc0f7..7d7ecce58 100644
--- a/src/core/eng_def.h
+++ b/src/core/libstate/eng_def.h
@@ -24,7 +24,10 @@ class BOTAN_DLL Default_Engine : public Engine
       NR_Operation* nr_op(const DL_Group&, const BigInt&, const BigInt&) const;
       ELG_Operation* elg_op(const DL_Group&, const BigInt&,
                             const BigInt&) const;
+
+#if defined(BOTAN_HAS_DH)
       DH_Operation* dh_op(const DL_Group&, const BigInt&) const;
+#endif
 
       Modular_Exponentiator* mod_exp(const BigInt&,
                                      Power_Mod::Usage_Hints) const;
diff --git a/src/core/libstate/engine.cpp b/src/core/libstate/engine.cpp
index fb2477936..13ab63193 100644
--- a/src/core/libstate/engine.cpp
+++ b/src/core/libstate/engine.cpp
@@ -83,6 +83,7 @@ ELG_Operation* elg_op(const DL_Group& group, const BigInt& y, const BigInt& x)
    throw Lookup_Error("Engine_Core::elg_op: Unable to find a working engine");
    }
 
+#if defined(BOTAN_HAS_DH)
 /*************************************************
 * Acquire a DH op                                *
 *************************************************/
@@ -99,6 +100,7 @@ DH_Operation* dh_op(const DL_Group& group, const BigInt& x)
 
    throw Lookup_Error("Engine_Core::dh_op: Unable to find a working engine");
    }
+#endif
 
 #if defined(BOTAN_HAS_ECDSA)
 /*************************************************
diff --git a/src/core/libstate/engine.h b/src/core/libstate/engine.h
index 212d02d7a..12c69385b 100644
--- a/src/core/libstate/engine.h
+++ b/src/core/libstate/engine.h
@@ -13,6 +13,10 @@
 #include <botan/basefilt.h>
 #include <botan/enums.h>
 
+#if defined(BOTAN_HAS_DH)
+  #include <botan/dh_op.h>
+#endif
+
 #if defined(BOTAN_HAS_ECDSA)
   #include <botan/ec_dompar.h>
 #endif
@@ -39,27 +43,41 @@ class BOTAN_DLL Engine
 
       virtual IF_Operation* if_op(const BigInt&, const BigInt&, const BigInt&,
                                   const BigInt&, const BigInt&, const BigInt&,
-                                  const BigInt&, const BigInt&) const;
+                                  const BigInt&, const BigInt&) const
+         { return 0; }
+
       virtual DSA_Operation* dsa_op(const DL_Group&, const BigInt&,
-                                    const BigInt&) const;
+                                    const BigInt&) const
+         { return 0; }
+
       virtual NR_Operation* nr_op(const DL_Group&, const BigInt&,
-                                  const BigInt&) const;
+                                  const BigInt&) const
+         { return 0; }
+
       virtual ELG_Operation* elg_op(const DL_Group&, const BigInt&,
-                                    const BigInt&) const;
-      virtual DH_Operation* dh_op(const DL_Group&, const BigInt&) const;
+                                    const BigInt&) const
+         { return 0; }
+
+#if defined(BOTAN_HAS_DH)
+      virtual DH_Operation* dh_op(const DL_Group&, const BigInt&) const
+         { return 0; }
+#endif
 
 #if defined(BOTAN_HAS_ECDSA)
       virtual ECDSA_Operation* ecdsa_op(const EC_Domain_Params& dom_pars,
                                         const BigInt& priv_key,
-                                        const PointGFp& pub_key) const;
+                                        const PointGFp& pub_key) const
+         { return 0; }
 
       virtual ECKAEG_Operation* eckaeg_op(const EC_Domain_Params& dom_pars,
                                           const BigInt& priv_key,
-                                          const PointGFp& pub_key) const;
+                                          const PointGFp& pub_key) const
+         { return 0; }
 #endif
 
       virtual Modular_Exponentiator* mod_exp(const BigInt&,
-                                             Power_Mod::Usage_Hints) const;
+                                             Power_Mod::Usage_Hints) const
+         { return 0; }
 
       virtual Keyed_Filter* get_cipher(const std::string&, Cipher_Dir);
 
@@ -129,7 +147,9 @@ NR_Operation* nr_op(const DL_Group&, const BigInt&, const BigInt&);
 
 ELG_Operation* elg_op(const DL_Group&, const BigInt&, const BigInt&);
 
+#if defined(BOTAN_HAS_DH)
 DH_Operation* dh_op(const DL_Group&, const BigInt&);
+#endif
 
 #if defined(BOTAN_HAS_ECDSA)
 ECDSA_Operation* ecdsa_op(const EC_Domain_Params& dom_pars,
diff --git a/src/core/libstate/info.txt b/src/core/libstate/info.txt
index f160ca771..6a54463ac 100644
--- a/src/core/libstate/info.txt
+++ b/src/core/libstate/info.txt
@@ -7,7 +7,9 @@ define LIBSTATE_MODULE
 <add>
 def_alg.cpp
 def_mode.cpp
+def_powm.cpp
 eng_base.cpp
+eng_def.h
 engine.cpp
 engine.h
 get_enc.cpp