Botan  2.11.0
Crypto and TLS for C++11
monty_exp.h
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1 /*
2 * (C) 2018 Jack Lloyd
3 *
4 * Botan is released under the Simplified BSD License (see license.txt)
5 */
6 
7 #ifndef BOTAN_MONTY_EXP_H_
8 #define BOTAN_MONTY_EXP_H_
9 
10 #include <memory>
11 
12 namespace Botan {
13 
14 class BigInt;
15 class Modular_Reducer;
16 
17 class Montgomery_Params;
18 
19 class Montgomery_Exponentation_State;
20 
21 /*
22 * Precompute for calculating values g^x mod p
23 */
24 std::shared_ptr<const Montgomery_Exponentation_State>
25 monty_precompute(std::shared_ptr<const Montgomery_Params> params_p,
26  const BigInt& g,
27  size_t window_bits,
28  bool const_time = true);
29 
30 /*
31 * Return g^k mod p
32 */
33 BigInt monty_execute(const Montgomery_Exponentation_State& precomputed_state,
34  const BigInt& k, size_t max_k_bits);
35 
36 /*
37 * Return g^k mod p taking variable time depending on k
38 * @warning only use this if k is public
39 */
40 BigInt monty_execute_vartime(const Montgomery_Exponentation_State& precomputed_state,
41  const BigInt& k);
42 
43 /**
44 * Return (x^z1 * y^z2) % p
45 */
46 BigInt monty_multi_exp(std::shared_ptr<const Montgomery_Params> params_p,
47  const BigInt& x,
48  const BigInt& z1,
49  const BigInt& y,
50  const BigInt& z2);
51 
52 }
53 
54 #endif
BigInt monty_multi_exp(std::shared_ptr< const Montgomery_Params > params_p, const BigInt &x_bn, const BigInt &z1, const BigInt &y_bn, const BigInt &z2)
Definition: monty_exp.cpp:179
BigInt monty_execute_vartime(const Montgomery_Exponentation_State &precomputed_state, const BigInt &k)
Definition: monty_exp.cpp:173
std::shared_ptr< const Montgomery_Exponentation_State > monty_precompute(std::shared_ptr< const Montgomery_Params > params, const BigInt &g, size_t window_bits, bool const_time)
Definition: monty_exp.cpp:159
Definition: alg_id.cpp:13
BigInt monty_execute(const Montgomery_Exponentation_State &precomputed_state, const BigInt &k, size_t max_k_bits)
Definition: monty_exp.cpp:167