1PROVIDER-ASYM_CIPHER(7ossl) OpenSSL PROVIDER-ASYM_CIPHER(7ossl)
2
6 provider-asym_cipher - The asym_cipher library <-> provider functions
7
9 #include <openssl/core_dispatch.h>
10 #include <openssl/core_names.h>
11 /*
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 /* Context management */
19 void *OSSL_FUNC_asym_cipher_newctx(void *provctx);
20 void OSSL_FUNC_asym_cipher_freectx(void *ctx);
21 void *OSSL_FUNC_asym_cipher_dupctx(void *ctx);
22 /* Encryption */
24 int OSSL_FUNC_asym_cipher_encrypt_init(void *ctx, void *provkey,
25 const OSSL_PARAM params[]);
26 int OSSL_FUNC_asym_cipher_encrypt(void *ctx, unsigned char *out, size_t *outlen,
27 size_t outsize, const unsigned char *in,
28 size_t inlen);
29 /* Decryption */
31 int OSSL_FUNC_asym_cipher_decrypt_init(void *ctx, void *provkey,
32 const OSSL_PARAM params[]);
33 int OSSL_FUNC_asym_cipher_decrypt(void *ctx, unsigned char *out, size_t *outlen,
34 size_t outsize, const unsigned char *in,
35 size_t inlen);
36 /* Asymmetric Cipher parameters */
38 int OSSL_FUNC_asym_cipher_get_ctx_params(void *ctx, OSSL_PARAM params[]);
39 const OSSL_PARAM *OSSL_FUNC_asym_cipher_gettable_ctx_params(void *provctx);
40 int OSSL_FUNC_asym_cipher_set_ctx_params(void *ctx, const OSSL_PARAM params[]);
41 const OSSL_PARAM *OSSL_FUNC_asym_cipher_settable_ctx_params(void *provctx);
42
44 This documentation is primarily aimed at provider authors. See
45 provider(7) for further information.
46 The asymmetric cipher (OSSL_OP_ASYM_CIPHER) operation enables providers
48 to implement asymmetric cipher algorithms and make them available to
49 applications via the API functions EVP_PKEY_encrypt(3),
50 EVP_PKEY_decrypt(3) and other related functions).
51 All "functions" mentioned here are passed as function pointers between
53 libcrypto and the provider in OSSL_DISPATCH arrays via OSSL_ALGORITHM
54 arrays that are returned by the provider's provider_query_operation()
55 function (see "Provider Functions" in provider-base(7)).
56 All these "functions" have a corresponding function type definition
58 named OSSL_FUNC_{name}_fn, and a helper function to retrieve the
59 function pointer from an OSSL_DISPATCH element named OSSL_FUNC_{name}.
60 For example, the "function" OSSL_FUNC_asym_cipher_newctx() has these:
61 typedef void *(OSSL_FUNC_asym_cipher_newctx_fn)(void *provctx);
63 static ossl_inline OSSL_FUNC_asym_cipher_newctx_fn
64 OSSL_FUNC_asym_cipher_newctx(const OSSL_DISPATCH *opf);
65 OSSL_DISPATCH arrays are indexed by numbers that are provided as macros
67 in openssl-core_dispatch.h(7), as follows:
68 OSSL_FUNC_asym_cipher_newctx OSSL_FUNC_ASYM_CIPHER_NEWCTX
70 OSSL_FUNC_asym_cipher_freectx OSSL_FUNC_ASYM_CIPHER_FREECTX
71 OSSL_FUNC_asym_cipher_dupctx OSSL_FUNC_ASYM_CIPHER_DUPCTX
72 OSSL_FUNC_asym_cipher_encrypt_init OSSL_FUNC_ASYM_CIPHER_ENCRYPT_INIT
74 OSSL_FUNC_asym_cipher_encrypt OSSL_FUNC_ASYM_CIPHER_ENCRYPT
75 OSSL_FUNC_asym_cipher_decrypt_init OSSL_FUNC_ASYM_CIPHER_DECRYPT_INIT
77 OSSL_FUNC_asym_cipher_decrypt OSSL_FUNC_ASYM_CIPHER_DECRYPT
78 OSSL_FUNC_asym_cipher_get_ctx_params OSSL_FUNC_ASYM_CIPHER_GET_CTX_PARAMS
80 OSSL_FUNC_asym_cipher_gettable_ctx_params OSSL_FUNC_ASYM_CIPHER_GETTABLE_CTX_PARAMS
81 OSSL_FUNC_asym_cipher_set_ctx_params OSSL_FUNC_ASYM_CIPHER_SET_CTX_PARAMS
82 OSSL_FUNC_asym_cipher_settable_ctx_params OSSL_FUNC_ASYM_CIPHER_SETTABLE_CTX_PARAMS
83 An asymmetric cipher algorithm implementation may not implement all of
85 these functions. In order to be a consistent set of functions a
86 provider must implement OSSL_FUNC_asym_cipher_newctx and
87 OSSL_FUNC_asym_cipher_freectx. It must also implement both of
88 OSSL_FUNC_asym_cipher_encrypt_init and OSSL_FUNC_asym_cipher_encrypt,
89 or both of OSSL_FUNC_asym_cipher_decrypt_init and
90 OSSL_FUNC_asym_cipher_decrypt. OSSL_FUNC_asym_cipher_get_ctx_params is
91 optional but if it is present then so must
92 OSSL_FUNC_asym_cipher_gettable_ctx_params. Similarly,
93 OSSL_FUNC_asym_cipher_set_ctx_params is optional but if it is present
94 then so must OSSL_FUNC_asym_cipher_settable_ctx_params.
95 An asymmetric cipher algorithm must also implement some mechanism for
97 generating, loading or importing keys via the key management
98 (OSSL_OP_KEYMGMT) operation. See provider-keymgmt(7) for further
99 details.
100 Context Management Functions
102 OSSL_FUNC_asym_cipher_newctx() should create and return a pointer to a
103 provider side structure for holding context information during an
104 asymmetric cipher operation. A pointer to this context will be passed
105 back in a number of the other asymmetric cipher operation function
106 calls. The parameter provctx is the provider context generated during
107 provider initialisation (see provider(7)).
108 OSSL_FUNC_asym_cipher_freectx() is passed a pointer to the provider
110 side asymmetric cipher context in the ctx parameter. This function
111 should free any resources associated with that context.
112 OSSL_FUNC_asym_cipher_dupctx() should duplicate the provider side
114 asymmetric cipher context in the ctx parameter and return the duplicate
115 copy.
116 Encryption Functions
118 OSSL_FUNC_asym_cipher_encrypt_init() initialises a context for an
119 asymmetric encryption given a provider side asymmetric cipher context
120 in the ctx parameter, and a pointer to a provider key object in the
121 provkey parameter. The params, if not NULL, should be set on the
122 context in a manner similar to using
123 OSSL_FUNC_asym_cipher_set_ctx_params(). The key object should have
124 been previously generated, loaded or imported into the provider using
125 the key management (OSSL_OP_KEYMGMT) operation (see
126 provider-keymgmt(7)>. OSSL_FUNC_asym_cipher_encrypt() performs the
127 actual encryption itself. A previously initialised asymmetric cipher
128 context is passed in the ctx parameter. The data to be encrypted is
129 pointed to by the in parameter which is inlen bytes long. Unless out
130 is NULL, the encrypted data should be written to the location pointed
131 to by the out parameter and it should not exceed outsize bytes in
132 length. The length of the encrypted data should be written to *outlen.
133 If out is NULL then the maximum length of the encrypted data should be
134 written to *outlen.
135 Decryption Functions
137 OSSL_FUNC_asym_cipher_decrypt_init() initialises a context for an
138 asymmetric decryption given a provider side asymmetric cipher context
139 in the ctx parameter, and a pointer to a provider key object in the
140 provkey parameter. The params, if not NULL, should be set on the
141 context in a manner similar to using
142 OSSL_FUNC_asym_cipher_set_ctx_params(). The key object should have
143 been previously generated, loaded or imported into the provider using
144 the key management (OSSL_OP_KEYMGMT) operation (see
145 provider-keymgmt(7)>.
146 OSSL_FUNC_asym_cipher_decrypt() performs the actual decryption itself.
148 A previously initialised asymmetric cipher context is passed in the ctx
149 parameter. The data to be decrypted is pointed to by the in parameter
150 which is inlen bytes long. Unless out is NULL, the decrypted data
151 should be written to the location pointed to by the out parameter and
152 it should not exceed outsize bytes in length. The length of the
153 decrypted data should be written to *outlen. If out is NULL then the
154 maximum length of the decrypted data should be written to *outlen.
155 Asymmetric Cipher Parameters
157 See OSSL_PARAM(3) for further details on the parameters structure used
158 by the OSSL_FUNC_asym_cipher_get_ctx_params() and
159 OSSL_FUNC_asym_cipher_set_ctx_params() functions.
160 OSSL_FUNC_asym_cipher_get_ctx_params() gets asymmetric cipher
162 parameters associated with the given provider side asymmetric cipher
163 context ctx and stores them in params. Passing NULL for params should
164 return true.
165 OSSL_FUNC_asym_cipher_set_ctx_params() sets the asymmetric cipher
167 parameters associated with the given provider side asymmetric cipher
168 context ctx to params. Any parameter settings are additional to any
169 that were previously set. Passing NULL for params should return true.
170 Parameters currently recognised by built-in asymmetric cipher
172 algorithms are as follows. Not all parameters are relevant to, or are
173 understood by all asymmetric cipher algorithms:
174 "pad-mode" (OSSL_ASYM_CIPHER_PARAM_PAD_MODE) <integer>
176 The type of padding to be used. The interpretation of this value
177 will depend on the algorithm in use. The default provider
178 understands these RSA padding modes: 1 (RSA_PKCS1_PADDING), 3
179 (RSA_NO_PADDING), 4 (RSA_PKCS1_OAEP_PADDING), 5 (RSA_X931_PADDING),
180 6 (RSA_PKCS1_PSS_PADDING) and 7 (RSA_PKCS1_WITH_TLS_PADDING). See
181 EVP_PKEY_CTX_set_rsa_padding(3) for further details.
182 "digest" (OSSL_ASYM_CIPHER_PARAM_OAEP_DIGEST) <UTF8 string>
184 Gets or sets the name of the OAEP digest algorithm used when OAEP
185 padding is in use.
186 "digest" (OSSL_ASYM_CIPHER_PARAM_DIGEST) <UTF8 string>
188 Gets or sets the name of the digest algorithm used by the algorithm
189 (where applicable).
190 "digest-props" (OSSL_ASYM_CIPHER_PARAM_OAEP_DIGEST_PROPS) <UTF8 string>
192 Gets or sets the properties to use when fetching the OAEP digest
193 algorithm.
194 "digest-props" (OSSL_ASYM_CIPHER_PARAM_DIGEST_PROPS) <UTF8 string>
196 Gets or sets the properties to use when fetching the cipher digest
197 algorithm.
198 "mgf1-digest" (OSSL_ASYM_CIPHER_PARAM_MGF1_DIGEST) <UTF8 string>
200 Gets or sets the name of the MGF1 digest algorithm used when OAEP
201 or PSS padding is in use.
202 "mgf1-digest-props" (OSSL_ASYM_CIPHER_PARAM_MGF1_DIGEST_PROPS) <UTF8
204 string>
205 Gets or sets the properties to use when fetching the MGF1 digest
206 algorithm.
207 "oaep-label" (OSSL_ASYM_CIPHER_PARAM_OAEP_LABEL) <octet string>
209 Gets or sets the OAEP label used when OAEP padding is in use.
210 "tls-client-version" (OSSL_ASYM_CIPHER_PARAM_TLS_CLIENT_VERSION)
212 <unsigned integer>
213 The TLS protocol version first requested by the client. See
214 RSA_PKCS1_WITH_TLS_PADDING on the page
215 EVP_PKEY_CTX_set_rsa_padding(3).
216 "tls-negotiated-version" (OSSL_ASYM_CIPHER_PARAM_TLS_CLIENT_VERSION)
218 <unsigned integer>
219 The negotiated TLS protocol version. See RSA_PKCS1_WITH_TLS_PADDING
220 on the page EVP_PKEY_CTX_set_rsa_padding(3).
221 OSSL_FUNC_asym_cipher_gettable_ctx_params() and
223 OSSL_FUNC_asym_cipher_settable_ctx_params() get a constant OSSL_PARAM
224 array that describes the gettable and settable parameters, i.e.
225 parameters that can be used with OSSL_FUNC_asym_cipherget_ctx_params()
226 and OSSL_FUNC_asym_cipher_set_ctx_params() respectively. See
227 OSSL_PARAM(3) for the use of OSSL_PARAM as parameter descriptor.
228
230 OSSL_FUNC_asym_cipher_newctx() and OSSL_FUNC_asym_cipher_dupctx()
231 should return the newly created provider side asymmetric cipher
232 context, or NULL on failure.
233 All other functions should return 1 for success or 0 on error.
235
237 provider(7)
238
240 The provider ASYM_CIPHER interface was introduced in OpenSSL 3.0.
241
243 Copyright 2019-2021 The OpenSSL Project Authors. All Rights Reserved.
244 Licensed under the Apache License 2.0 (the "License"). You may not use
246 this file except in compliance with the License. You can obtain a copy
247 in the file LICENSE in the source distribution or at
248 <https://www.openssl.org/source/license.html>.
2493.0.5 2022-07-05 PROVIDER-ASYM_CIPHER(7ossl)