Botan 2.13.0 Crypto and TLS for C++11

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polyn_gf2m.h
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1 /*
2 * (C) Copyright Projet SECRET, INRIA, Rocquencourt
3 * (C) Bhaskar Biswas and Nicolas Sendrier
4 *
5 * (C) 2014 cryptosource GmbH
6 * (C) 2014 Falko Strenzke fstrenzke@cryptosource.de
7 *
8 * Botan is released under the Simplified BSD License (see license.txt)
9 *
10 */
11
12 #ifndef BOTAN_POLYN_GF2M_H_
13 #define BOTAN_POLYN_GF2M_H_
14
15 #include <botan/secmem.h>
16 #include <botan/gf2m_small_m.h>
17 #include <utility>
18 #include <string>
19
20 //BOTAN_FUTURE_INTERNAL_HEADER(polyn_gf2m.h)
21
22 namespace Botan {
23
24 class RandomNumberGenerator;
25
26 class polyn_gf2m
27 {
28 public:
29 /**
30 * create a zero polynomial:
31 */
32 explicit polyn_gf2m(std::shared_ptr<GF2m_Field> sp_field);
33
34 polyn_gf2m() : m_deg(-1) {}
35
36 polyn_gf2m(const secure_vector<uint8_t>& encoded, std::shared_ptr<GF2m_Field> sp_field);
37
38 polyn_gf2m& operator=(const polyn_gf2m&) = default;
39
40 /**
41 * create zero polynomial with reservation of space for a degree d polynomial
42 */
43 polyn_gf2m(int d, std::shared_ptr<GF2m_Field> sp_field);
44
45 polyn_gf2m(polyn_gf2m const& other);
46
47 /**
48 * random irreducible polynomial of degree t
49 */
50 polyn_gf2m(size_t t, RandomNumberGenerator& rng, std::shared_ptr<GF2m_Field> sp_field);
51
52 /** decode a polynomial from memory: **/
53 polyn_gf2m(const uint8_t* mem, uint32_t mem_len, std::shared_ptr<GF2m_Field> sp_field);
54
55 /**
56 * create a polynomial from memory area (encoded)
57 */
58 polyn_gf2m(int degree, const uint8_t* mem, size_t mem_byte_len, std::shared_ptr<GF2m_Field> sp_field);
59
60 bool operator==(const polyn_gf2m & other) const ;
61
62 bool operator!=(const polyn_gf2m & other) const { return !(*this == other); }
63
64 polyn_gf2m(polyn_gf2m&& other)
65 {
66 this->swap(other);
67 }
68
69 polyn_gf2m & operator=(polyn_gf2m&& other)
70 {
71 if(this != &other)
72 {
73 this->swap(other);
74 }
75 return *this;
76 }
77
78 void swap(polyn_gf2m& other);
79
80 secure_vector<uint8_t> encode() const;
81
82 std::shared_ptr<GF2m_Field> get_sp_field() const
83 { return m_sp_field; }
84
85 gf2m& operator[](size_t i) { return coeff[i]; }
86
87 gf2m operator[](size_t i) const { return coeff[i]; }
88
89 gf2m get_lead_coef() const { return coeff[m_deg]; }
90
91 gf2m get_coef(size_t i) const { return coeff[i]; }
92
93 inline void set_coef(size_t i, gf2m v)
94 {
95 coeff[i] = v;
96 }
97
98 inline void add_to_coef(size_t i, gf2m v)
99 {
100 coeff[i] ^= v;
101 }
102
103 std::string to_string() const;
104
105 void encode(uint32_t min_numo_coeffs, uint8_t* mem, uint32_t mem_len) const;
106
107 int get_degree() const;
108
109 /**
110 * determine the degree in a timing secure manner. the timing of this function
111 * only depends on the number of allocated coefficients, not on the actual
112 * degree
113 */
114 int calc_degree_secure() const;
115
116 size_t degppf(const polyn_gf2m& g);
117
118 static std::vector<polyn_gf2m> sqmod_init(const polyn_gf2m & g);
119
120 static std::vector<polyn_gf2m> sqrt_mod_init(const polyn_gf2m & g);
121
122
123 polyn_gf2m sqmod(const std::vector<polyn_gf2m> & sq, int d);
124 void set_to_zero();
125 gf2m eval(gf2m a);
126
127 static std::pair<polyn_gf2m, polyn_gf2m> eea_with_coefficients(const polyn_gf2m & p,
128 const polyn_gf2m & g,
129 int break_deg);
130
131 void patchup_deg_secure( uint32_t trgt_deg, volatile gf2m patch_elem);
132
133 private:
134
135 void set_degree(int d) { m_deg = d; }
136
137 void poly_shiftmod( const polyn_gf2m & g);
138 void realloc(uint32_t new_size);
139 static polyn_gf2m gcd(polyn_gf2m const& p1, polyn_gf2m const& p2);
140
141 /**
142 * destructive:
143 */
144 static void remainder(polyn_gf2m & p, const polyn_gf2m & g);
145
146 static polyn_gf2m gcd_aux(polyn_gf2m& p1, polyn_gf2m& p2);
147 public:
148 // public member variable:
149 int m_deg;
150
151 // public member variable:
152 secure_vector<gf2m> coeff;
153
154 // public member variable:
155 std::shared_ptr<GF2m_Field> m_sp_field;
156 };
157
158 gf2m random_gf2m(RandomNumberGenerator& rng);
159 gf2m random_code_element(uint16_t code_length, RandomNumberGenerator& rng);
160
161 std::vector<polyn_gf2m> syndrome_init(polyn_gf2m const& generator, std::vector<gf2m> const& support, int n);
162
163 /**
164 * Find the roots of a polynomial over GF(2^m) using the method by Federenko et al.
165 */
166 secure_vector<gf2m> find_roots_gf2m_decomp(const polyn_gf2m & polyn, size_t code_length);
167
168 }
169
170 #endif
Botan::polyn_gf2m::m_deg
int m_deg
Definition: polyn_gf2m.h:149
Botan::polyn_gf2m
Definition: polyn_gf2m.h:26
Botan::polyn_gf2m::degppf
size_t degppf(const polyn_gf2m &g)
Definition: polyn_gf2m.cpp:390
Botan::RandomNumberGenerator
Definition: rng.h:24
Botan::polyn_gf2m::operator[]
gf2m & operator[](size_t i)
Definition: polyn_gf2m.h:85
Botan::polyn_gf2m::operator[]
gf2m operator[](size_t i) const
Definition: polyn_gf2m.h:87
Botan::polyn_gf2m::operator!=
bool operator!=(const polyn_gf2m &other) const
Definition: polyn_gf2m.h:62
Botan::polyn_gf2m::sqmod
polyn_gf2m sqmod(const std::vector< polyn_gf2m > &sq, int d)
Definition: polyn_gf2m.cpp:323
Botan::polyn_gf2m::get_lead_coef
gf2m get_lead_coef() const
Definition: polyn_gf2m.h:89
Botan::polyn_gf2m::encode
secure_vector< uint8_t > encode() const
Definition: polyn_gf2m.cpp:769
Botan::polyn_gf2m::sqrt_mod_init
static std::vector< polyn_gf2m > sqrt_mod_init(const polyn_gf2m &g)
Definition: polyn_gf2m.cpp:676
Botan::polyn_gf2m::calc_degree_secure
int calc_degree_secure() const
Definition: polyn_gf2m.cpp:46
Botan::polyn_gf2m::operator=
polyn_gf2m & operator=(polyn_gf2m &&other)
Definition: polyn_gf2m.h:69
Botan::secure_vector
std::vector< T, secure_allocator< T >> secure_vector
Definition: secmem.h:65
Botan::polyn_gf2m::set_to_zero
void set_to_zero()
Definition: polyn_gf2m.cpp:222
Botan::polyn_gf2m::patchup_deg_secure
void patchup_deg_secure(uint32_t trgt_deg, volatile gf2m patch_elem)
Definition: polyn_gf2m.cpp:429
Botan::polyn_gf2m::get_degree
int get_degree() const
Definition: polyn_gf2m.cpp:228
Botan::gf2m
uint16_t gf2m
Definition: gf2m_small_m.h:23
Botan
Definition: alg_id.cpp:13
Botan::polyn_gf2m::polyn_gf2m
polyn_gf2m(polyn_gf2m &&other)
Definition: polyn_gf2m.h:64
Botan::polyn_gf2m::get_sp_field
std::shared_ptr< GF2m_Field > get_sp_field() const
Definition: polyn_gf2m.h:82
Botan::polyn_gf2m::sqmod_init
static std::vector< polyn_gf2m > sqmod_init(const polyn_gf2m &g)
Definition: polyn_gf2m.cpp:289
Botan::polyn_gf2m::coeff
secure_vector< gf2m > coeff
Definition: polyn_gf2m.h:152
Botan::polyn_gf2m::operator==
bool operator==(const polyn_gf2m &other) const
Definition: polyn_gf2m.cpp:797
Botan::polyn_gf2m::add_to_coef
void add_to_coef(size_t i, gf2m v)
Definition: polyn_gf2m.h:98
Botan::random_code_element
gf2m random_code_element(uint16_t code_length, RandomNumberGenerator &rng)
Definition: polyn_gf2m.cpp:71
Botan::syndrome_init
std::vector< polyn_gf2m > syndrome_init(polyn_gf2m const &generator, std::vector< gf2m > const &support, int n)
Definition: polyn_gf2m.cpp:721
Botan::polyn_gf2m::polyn_gf2m
polyn_gf2m()
Definition: polyn_gf2m.h:34
Botan::polyn_gf2m::eea_with_coefficients
static std::pair< polyn_gf2m, polyn_gf2m > eea_with_coefficients(const polyn_gf2m &p, const polyn_gf2m &g, int break_deg)
Definition: polyn_gf2m.cpp:448
Botan::polyn_gf2m::to_string
std::string to_string() const
Definition: polyn_gf2m.cpp:104
Botan::polyn_gf2m::operator=
polyn_gf2m & operator=(const polyn_gf2m &)=default
Botan::find_roots_gf2m_decomp
secure_vector< gf2m > find_roots_gf2m_decomp(const polyn_gf2m &polyn, size_t code_length)
Definition: gf2m_rootfind_dcmp.cpp:308
Botan::polyn_gf2m::get_coef
gf2m get_coef(size_t i) const
Definition: polyn_gf2m.h:91
Botan::random_gf2m
gf2m random_gf2m(RandomNumberGenerator &rng)
Definition: polyn_gf2m.cpp:64
Botan::polyn_gf2m::swap
void swap(polyn_gf2m &other)
Definition: polyn_gf2m.cpp:790
Botan::polyn_gf2m::m_sp_field
std::shared_ptr< GF2m_Field > m_sp_field
Definition: polyn_gf2m.h:155
Botan::polyn_gf2m::eval
gf2m eval(gf2m a)
Definition: polyn_gf2m.cpp:254
Botan::polyn_gf2m::set_coef
void set_coef(size_t i, gf2m v)
Definition: polyn_gf2m.h:93