1PROVIDER-MAC(7ossl) OpenSSL PROVIDER-MAC(7ossl)
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6 provider-mac - The mac library <-> provider functions
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9 #include <openssl/core_dispatch.h>
10 #include <openssl/core_names.h>
11
12 /*
13 * None of these are actual functions, but are displayed like this for
14 * the function signatures for functions that are offered as function
15 * pointers in OSSL_DISPATCH arrays.
16 */
17
18 /* Context management */
19 void *OSSL_FUNC_mac_newctx(void *provctx);
20 void OSSL_FUNC_mac_freectx(void *mctx);
21 void *OSSL_FUNC_mac_dupctx(void *src);
22
23 /* Encryption/decryption */
24 int OSSL_FUNC_mac_init(void *mctx, unsigned char *key, size_t keylen,
25 const OSSL_PARAM params[]);
26 int OSSL_FUNC_mac_update(void *mctx, const unsigned char *in, size_t inl);
27 int OSSL_FUNC_mac_final(void *mctx, unsigned char *out, size_t *outl, size_t outsize);
28
29 /* MAC parameter descriptors */
30 const OSSL_PARAM *OSSL_FUNC_mac_gettable_params(void *provctx);
31 const OSSL_PARAM *OSSL_FUNC_mac_gettable_ctx_params(void *mctx, void *provctx);
32 const OSSL_PARAM *OSSL_FUNC_mac_settable_ctx_params(void *mctx, void *provctx);
33
34 /* MAC parameters */
35 int OSSL_FUNC_mac_get_params(OSSL_PARAM params[]);
36 int OSSL_FUNC_mac_get_ctx_params(void *mctx, OSSL_PARAM params[]);
37 int OSSL_FUNC_mac_set_ctx_params(void *mctx, const OSSL_PARAM params[]);
38
40 This documentation is primarily aimed at provider authors. See
41 provider(7) for further information.
42
43 The MAC operation enables providers to implement mac algorithms and
44 make them available to applications via the API functions
45 EVP_MAC_init(3), EVP_MAC_update(3) and EVP_MAC_final(3).
46
47 All "functions" mentioned here are passed as function pointers between
48 libcrypto and the provider in OSSL_DISPATCH arrays via OSSL_ALGORITHM
49 arrays that are returned by the provider's provider_query_operation()
50 function (see "Provider Functions" in provider-base(7)).
51
52 All these "functions" have a corresponding function type definition
53 named OSSL_FUNC_{name}_fn, and a helper function to retrieve the
54 function pointer from an OSSL_DISPATCH element named OSSL_FUNC_{name}.
55 For example, the "function" OSSL_FUNC_mac_newctx() has these:
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57 typedef void *(OSSL_FUNC_mac_newctx_fn)(void *provctx);
58 static ossl_inline OSSL_FUNC_mac_newctx_fn
59 OSSL_FUNC_mac_newctx(const OSSL_DISPATCH *opf);
60
61 OSSL_DISPATCH arrays are indexed by numbers that are provided as macros
62 in openssl-core_dispatch.h(7), as follows:
63
64 OSSL_FUNC_mac_newctx OSSL_FUNC_MAC_NEWCTX
65 OSSL_FUNC_mac_freectx OSSL_FUNC_MAC_FREECTX
66 OSSL_FUNC_mac_dupctx OSSL_FUNC_MAC_DUPCTX
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68 OSSL_FUNC_mac_init OSSL_FUNC_MAC_INIT
69 OSSL_FUNC_mac_update OSSL_FUNC_MAC_UPDATE
70 OSSL_FUNC_mac_final OSSL_FUNC_MAC_FINAL
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72 OSSL_FUNC_mac_get_params OSSL_FUNC_MAC_GET_PARAMS
73 OSSL_FUNC_mac_get_ctx_params OSSL_FUNC_MAC_GET_CTX_PARAMS
74 OSSL_FUNC_mac_set_ctx_params OSSL_FUNC_MAC_SET_CTX_PARAMS
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76 OSSL_FUNC_mac_gettable_params OSSL_FUNC_MAC_GETTABLE_PARAMS
77 OSSL_FUNC_mac_gettable_ctx_params OSSL_FUNC_MAC_GETTABLE_CTX_PARAMS
78 OSSL_FUNC_mac_settable_ctx_params OSSL_FUNC_MAC_SETTABLE_CTX_PARAMS
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80 A mac algorithm implementation may not implement all of these
81 functions. In order to be a consistent set of functions, at least the
82 following functions must be implemented: OSSL_FUNC_mac_newctx(),
83 OSSL_FUNC_mac_freectx(), OSSL_FUNC_mac_init(), OSSL_FUNC_mac_update(),
84 OSSL_FUNC_mac_final(). All other functions are optional.
85
86 Context Management Functions
87 OSSL_FUNC_mac_newctx() should create and return a pointer to a provider
88 side structure for holding context information during a mac operation.
89 A pointer to this context will be passed back in a number of the other
90 mac operation function calls. The parameter provctx is the provider
91 context generated during provider initialisation (see provider(7)).
92
93 OSSL_FUNC_mac_freectx() is passed a pointer to the provider side mac
94 context in the mctx parameter. If it receives NULL as mctx value, it
95 should not do anything other than return. This function should free
96 any resources associated with that context.
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98 OSSL_FUNC_mac_dupctx() should duplicate the provider side mac context
99 in the mctx parameter and return the duplicate copy.
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101 Encryption/Decryption Functions
102 OSSL_FUNC_mac_init() initialises a mac operation given a newly created
103 provider side mac context in the mctx parameter. The params are set
104 before setting the MAC key of keylen bytes.
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106 OSSL_FUNC_mac_update() is called to supply data for MAC computation of
107 a previously initialised mac operation. The mctx parameter contains a
108 pointer to a previously initialised provider side context.
109 OSSL_FUNC_mac_update() may be called multiple times for a single mac
110 operation.
111
112 OSSL_FUNC_mac_final() completes the MAC computation started through
113 previous OSSL_FUNC_mac_init() and OSSL_FUNC_mac_update() calls. The
114 mctx parameter contains a pointer to the provider side context. The
115 resulting MAC should be written to out and the amount of data written
116 to *outl, which should not exceed outsize bytes. The same expectations
117 apply to outsize as documented for EVP_MAC_final(3).
118
119 Mac Parameters
120 See OSSL_PARAM(3) for further details on the parameters structure used
121 by these functions.
122
123 OSSL_FUNC_mac_get_params() gets details of parameter values associated
124 with the provider algorithm and stores them in params.
125
126 OSSL_FUNC_mac_set_ctx_params() sets mac parameters associated with the
127 given provider side mac context mctx to params. Any parameter settings
128 are additional to any that were previously set. Passing NULL for
129 params should return true.
130
131 OSSL_FUNC_mac_get_ctx_params() gets details of currently set parameter
132 values associated with the given provider side mac context mctx and
133 stores them in params. Passing NULL for params should return true.
134
135 OSSL_FUNC_mac_gettable_params(), OSSL_FUNC_mac_gettable_ctx_params(),
136 and OSSL_FUNC_mac_settable_ctx_params() all return constant OSSL_PARAM
137 arrays as descriptors of the parameters that
138 OSSL_FUNC_mac_get_params(), OSSL_FUNC_mac_get_ctx_params(), and
139 OSSL_FUNC_mac_set_ctx_params() can handle, respectively.
140 OSSL_FUNC_mac_gettable_ctx_params() and
141 OSSL_FUNC_mac_settable_ctx_params() will return the parameters
142 associated with the provider side context mctx in its current state if
143 it is not NULL. Otherwise, they return the parameters associated with
144 the provider side algorithm provctx.
145
146 All MAC implementations are expected to handle the following
147 parameters:
148
149 with OSSL_FUNC_set_ctx_params():
150 "key" (OSSL_MAC_PARAM_KEY) <octet string>
151 Sets the key in the associated MAC ctx. This is identical to
152 passing a key argument to the OSSL_FUNC_mac_init() function.
153
154 with OSSL_FUNC_get_params():
155 "size" (OSSL_MAC_PARAM_SIZE) <integer>
156 Can be used to get the default MAC size (which might be the
157 only allowable MAC size for the implementation).
158
159 Note that some implementations allow setting the size that the
160 resulting MAC should have as well, see the documentation of the
161 implementation.
162
163 "size" (OSSL_MAC_PARAM_BLOCK_SIZE) <integer>
164 Can be used to get the MAC block size (if supported by the
165 algorithm).
166
168 The MAC life-cycle is described in life_cycle-rand(7). Providers
169 should ensure that the various transitions listed there are supported.
170 At some point the EVP layer will begin enforcing the listed
171 transitions.
172
174 OSSL_FUNC_mac_newctx() and OSSL_FUNC_mac_dupctx() should return the
175 newly created provider side mac context, or NULL on failure.
176
177 OSSL_FUNC_mac_init(), OSSL_FUNC_mac_update(), OSSL_FUNC_mac_final(),
178 OSSL_FUNC_mac_get_params(), OSSL_FUNC_mac_get_ctx_params() and
179 OSSL_FUNC_mac_set_ctx_params() should return 1 for success or 0 on
180 error.
181
182 OSSL_FUNC_mac_gettable_params(), OSSL_FUNC_mac_gettable_ctx_params()
183 and OSSL_FUNC_mac_settable_ctx_params() should return a constant
184 OSSL_PARAM array, or NULL if none is offered.
185
187 provider(7), EVP_MAC-BLAKE2(7), EVP_MAC-CMAC(7), EVP_MAC-GMAC(7),
188 EVP_MAC-HMAC(7), EVP_MAC-KMAC(7), EVP_MAC-Poly1305(7),
189 EVP_MAC-Siphash(7), life_cycle-mac(7), EVP_MAC(3)
190
192 The provider MAC interface was introduced in OpenSSL 3.0.
193
195 Copyright 2019-2022 The OpenSSL Project Authors. All Rights Reserved.
196
197 Licensed under the Apache License 2.0 (the "License"). You may not use
198 this file except in compliance with the License. You can obtain a copy
199 in the file LICENSE in the source distribution or at
200 <https://www.openssl.org/source/license.html>.
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2043.0.5 2022-11-01 PROVIDER-MAC(7ossl)