This is the first checkin to net.randombit.botan.modularized, which

has the intent of modularizing Botan's source code, and making it
much easier to add or remove various things at compile time.

In this first checkin:

Add support for nested directories in modules/ and move all the modules
into grouped directories like entropy/ or compression/

Currently this is not ideal, it will _only_ find code in
modules/*/*/modinfo.txt, while it would be much better to allow for
arbitrary nestings under modules (find modules -name modinfo.txt)
for more complicated setups.

This 'new' (OMG I've found directories!) structure allows for a more free
naming convention (no need for leading es_, ml_, etc to group names, though
some keep it for lack of a more meaningful name being obvious to me right
at the moment).

1 files changed, 52 insertions, 0 deletions

diff --git a/modules/engine/openssl/bn_powm.cpp b/modules/engine/openssl/bn_powm.cpp
new file mode 100644
index 000000000..f54411240
--- /dev/null
+++ b/modules/engine/openssl/bn_powm.cpp
@@ -0,0 +1,52 @@
+/*************************************************
+* OpenSSL Modular Exponentiation Source File     *
+* (C) 1999-2007 Jack Lloyd                       *
+*************************************************/
+
+#include <botan/eng_ossl.h>
+#include <botan/bn_wrap.h>
+
+namespace Botan {
+
+namespace {
+
+/*************************************************
+* OpenSSL Modular Exponentiator                  *
+*************************************************/
+class OpenSSL_Modular_Exponentiator : public Modular_Exponentiator
+   {
+   public:
+      void set_base(const BigInt& b) { base = b; }
+      void set_exponent(const BigInt& e) { exp = e; }
+      BigInt execute() const;
+      Modular_Exponentiator* copy() const
+         { return new OpenSSL_Modular_Exponentiator(*this); }
+
+      OpenSSL_Modular_Exponentiator(const BigInt& n) : mod(n) {}
+   private:
+      OSSL_BN base, exp, mod;
+      OSSL_BN_CTX ctx;
+   };
+
+/*************************************************
+* Compute the result                             *
+*************************************************/
+BigInt OpenSSL_Modular_Exponentiator::execute() const
+   {
+   OSSL_BN r;
+   BN_mod_exp(r.value, base.value, exp.value, mod.value, ctx.value);
+   return r.to_bigint();
+   }
+
+}
+
+/*************************************************
+* Return the OpenSSL-based modular exponentiator *
+*************************************************/
+Modular_Exponentiator* OpenSSL_Engine::mod_exp(const BigInt& n,
+                                           Power_Mod::Usage_Hints) const
+   {
+   return new OpenSSL_Modular_Exponentiator(n);
+   }
+
+}