aboutsummaryrefslogtreecommitdiffstats
path: root/src/lib/math/numbertheory/def_powm.h
blob: fe705bf96fe1b74c1bc4b462e2c7c767d34cfd26 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
/*
* Modular Exponentiation
* (C) 1999-2007 Jack Lloyd
*
* Botan is released under the Simplified BSD License (see license.txt)
*/

#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 Fixed_Window_Exponentiator final : public Modular_Exponentiator
   {
   public:
      void set_exponent(const BigInt&) override;
      void set_base(const BigInt&) override;
      BigInt execute() const override;

      Modular_Exponentiator* copy() const override
         { return new Fixed_Window_Exponentiator(*this); }

      Fixed_Window_Exponentiator(const BigInt&, Power_Mod::Usage_Hints);
   private:
      Modular_Reducer m_reducer;
      BigInt m_exp;
      size_t m_window_bits;
      std::vector<BigInt> m_g;
      Power_Mod::Usage_Hints m_hints;
   };

class Montgomery_Exponentation_State;

/**
* Montgomery Exponentiator
*/
class Montgomery_Exponentiator final : public Modular_Exponentiator
   {
   public:
      void set_exponent(const BigInt&) override;
      void set_base(const BigInt&) override;
      BigInt execute() const override;

      Modular_Exponentiator* copy() const override
         { return new Montgomery_Exponentiator(*this); }

      Montgomery_Exponentiator(const BigInt&, Power_Mod::Usage_Hints);
   private:
      std::shared_ptr<const Montgomery_Exponentation_State> m_monty;
      BigInt m_p;
      Modular_Reducer m_mod_p;
      BigInt m_e;
      Power_Mod::Usage_Hints m_hints;
   };

}

#endif