1 files changed, 62 insertions, 0 deletions
diff --git a/src/math/numbertheory/def_powm.h b/src/math/numbertheory/def_powm.h
new file mode 100644
index 000000000..c91ff002c
--- /dev/null
+++ b/src/math/numbertheory/def_powm.h
@@ -0,0 +1,62 @@
+/*************************************************
+* Modular Exponentiation Header File             *
+* (C) 1999-2007 Jack Lloyd                       *
+*************************************************/
+
+#ifndef BOTAN_DEFAULT_MODEXP_H__
+#define BOTAN_DEFAULT_MODEXP_H__
+
+#include <botan/pow_mod.h>
+#include <botan/reducer.h>
+#include <vector>
+
+namespace Botan {
+
+/*************************************************
+* Fixed Window Exponentiator                     *
+*************************************************/
+class BOTAN_DLL Fixed_Window_Exponentiator : public Modular_Exponentiator
+   {
+   public:
+      void set_exponent(const BigInt&);
+      void set_base(const BigInt&);
+      BigInt execute() const;
+
+      Modular_Exponentiator* copy() const
+         { return new Fixed_Window_Exponentiator(*this); }
+
+      Fixed_Window_Exponentiator(const BigInt&, Power_Mod::Usage_Hints);
+   private:
+      Modular_Reducer reducer;
+      BigInt exp;
+      u32bit window_bits;
+      std::vector<BigInt> g;
+      Power_Mod::Usage_Hints hints;
+   };
+
+/*************************************************
+* Montgomery Exponentiator                       *
+*************************************************/
+class BOTAN_DLL Montgomery_Exponentiator : public Modular_Exponentiator
+   {
+   public:
+      void set_exponent(const BigInt&);
+      void set_base(const BigInt&);
+      BigInt execute() const;
+
+      Modular_Exponentiator* copy() const
+         { return new Montgomery_Exponentiator(*this); }
+
+      Montgomery_Exponentiator(const BigInt&, Power_Mod::Usage_Hints);
+   private:
+      BigInt exp, modulus;
+      BigInt R2, R_mod;
+      std::vector<BigInt> g;
+      word mod_prime;
+      u32bit mod_words, exp_bits, window_bits;
+      Power_Mod::Usage_Hints hints;
+   };
+
+}
+
+#endif