/src/botan/build/include/public/botan/mac.h
Line | Count | Source |
1 | | /* |
2 | | * Base class for message authentiction codes |
3 | | * (C) 1999-2007 Jack Lloyd |
4 | | * |
5 | | * Botan is released under the Simplified BSD License (see license.txt) |
6 | | */ |
7 | | |
8 | | #ifndef BOTAN_MESSAGE_AUTH_CODE_BASE_H_ |
9 | | #define BOTAN_MESSAGE_AUTH_CODE_BASE_H_ |
10 | | |
11 | | #include <botan/buf_comp.h> |
12 | | #include <botan/sym_algo.h> |
13 | | #include <memory> |
14 | | #include <span> |
15 | | #include <string> |
16 | | |
17 | | namespace Botan { |
18 | | |
19 | | /** |
20 | | * This class represents Message Authentication Code (MAC) objects. |
21 | | */ |
22 | | class BOTAN_PUBLIC_API(2, 0) MessageAuthenticationCode : public Buffered_Computation, |
23 | | public SymmetricAlgorithm { |
24 | | public: |
25 | | /** |
26 | | * Create an instance based on a name |
27 | | * If provider is empty then best available is chosen. |
28 | | * @param algo_spec algorithm name |
29 | | * @param provider provider implementation to use |
30 | | * @return a null pointer if the algo/provider combination cannot be found |
31 | | */ |
32 | | static std::unique_ptr<MessageAuthenticationCode> create(std::string_view algo_spec, |
33 | | std::string_view provider = ""); |
34 | | |
35 | | /* |
36 | | * Create an instance based on a name |
37 | | * If provider is empty then best available is chosen. |
38 | | * @param algo_spec algorithm name |
39 | | * @param provider provider implementation to use |
40 | | * Throws a Lookup_Error if algo/provider combination cannot be found |
41 | | */ |
42 | | static std::unique_ptr<MessageAuthenticationCode> create_or_throw(std::string_view algo_spec, |
43 | | std::string_view provider = ""); |
44 | | |
45 | | /** |
46 | | * @return list of available providers for this algorithm, empty if not available |
47 | | */ |
48 | | static std::vector<std::string> providers(std::string_view algo_spec); |
49 | | |
50 | | /** |
51 | | * Prepare for processing a message under the specified nonce |
52 | | * |
53 | | * Most MACs neither require nor support a nonce; for these algorithms |
54 | | * calling start() is optional and calling it with anything other than |
55 | | * an empty string is an error. One MAC which *requires* a per-message |
56 | | * nonce be specified is GMAC. |
57 | | * |
58 | | * Default implementation simply rejects all non-empty nonces |
59 | | * since most hash/MAC algorithms do not support randomization |
60 | | * |
61 | | * @param nonce the message nonce bytes |
62 | | */ |
63 | 0 | void start(std::span<const uint8_t> nonce) { start_msg(nonce); } |
64 | | |
65 | | /** |
66 | | * Begin processing a message. |
67 | | * @param nonce the per message nonce |
68 | | * @param nonce_len length of nonce |
69 | | */ |
70 | 0 | void start(const uint8_t nonce[], size_t nonce_len) { start_msg({nonce, nonce_len}); } |
71 | | |
72 | | /** |
73 | | * Begin processing a message. |
74 | | */ |
75 | 0 | void start() { return start_msg({}); } |
76 | | |
77 | | /** |
78 | | * Verify a MAC. |
79 | | * @param in the MAC to verify as a byte array |
80 | | * @param length the length of param in |
81 | | * @return true if the MAC is valid, false otherwise |
82 | | */ |
83 | 0 | bool verify_mac(const uint8_t in[], size_t length) { return verify_mac_result({in, length}); } |
84 | | |
85 | | /** |
86 | | * Verify a MAC. |
87 | | * @param in the MAC to verify as a byte array |
88 | | * @return true if the MAC is valid, false otherwise |
89 | | */ |
90 | 0 | bool verify_mac(std::span<const uint8_t> in) { return verify_mac_result(in); } |
91 | | |
92 | | /** |
93 | | * @return new object representing the same algorithm as *this |
94 | | */ |
95 | | virtual std::unique_ptr<MessageAuthenticationCode> new_object() const = 0; |
96 | | |
97 | | /** |
98 | | * Get a new object representing the same algorithm as *this |
99 | | */ |
100 | 0 | MessageAuthenticationCode* clone() const { return this->new_object().release(); } |
101 | | |
102 | | /** |
103 | | * @return provider information about this implementation. Default is "base", |
104 | | * might also return "sse2", "avx2", "openssl", or some other arbitrary string. |
105 | | */ |
106 | 0 | virtual std::string provider() const { return "base"; } |
107 | | |
108 | | /** |
109 | | * @return if a fresh key must be set for each message that is processed. |
110 | | * |
111 | | * This is required for certain polynomial-based MACs which are insecure |
112 | | * if a key is ever reused for two different messages. |
113 | | */ |
114 | 0 | virtual bool fresh_key_required_per_message() const { return false; } |
115 | | |
116 | | protected: |
117 | | /** |
118 | | * Prepare for processing a message under the specified nonce |
119 | | * |
120 | | * If the MAC does not support nonces, it should not override the default |
121 | | * implementation. |
122 | | */ |
123 | | virtual void start_msg(std::span<const uint8_t> nonce); |
124 | | |
125 | | /** |
126 | | * Verify the MACs final result |
127 | | */ |
128 | | virtual bool verify_mac_result(std::span<const uint8_t> in); |
129 | | }; |
130 | | |
131 | | typedef MessageAuthenticationCode MAC; |
132 | | |
133 | | } // namespace Botan |
134 | | |
135 | | #endif |