1EVP_ASYM_CIPHER_FREE(3ossl)         OpenSSL        EVP_ASYM_CIPHER_FREE(3ossl)
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NAME

6       EVP_ASYM_CIPHER_fetch, EVP_ASYM_CIPHER_free, EVP_ASYM_CIPHER_up_ref,
7       EVP_ASYM_CIPHER_is_a, EVP_ASYM_CIPHER_get0_provider,
8       EVP_ASYM_CIPHER_do_all_provided, EVP_ASYM_CIPHER_names_do_all,
9       EVP_ASYM_CIPHER_get0_name, EVP_ASYM_CIPHER_get0_description,
10       EVP_ASYM_CIPHER_gettable_ctx_params,
11       EVP_ASYM_CIPHER_settable_ctx_params - Functions to manage
12       EVP_ASYM_CIPHER algorithm objects
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SYNOPSIS

15        #include <openssl/evp.h>
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17        EVP_ASYM_CIPHER *EVP_ASYM_CIPHER_fetch(OSSL_LIB_CTX *ctx, const char *algorithm,
18                                               const char *properties);
19        void EVP_ASYM_CIPHER_free(EVP_ASYM_CIPHER *cipher);
20        int EVP_ASYM_CIPHER_up_ref(EVP_ASYM_CIPHER *cipher);
21        const char *EVP_ASYM_CIPHER_get0_name(const EVP_ASYM_CIPHER *cipher);
22        int EVP_ASYM_CIPHER_is_a(const EVP_ASYM_CIPHER *cipher, const char *name);
23        OSSL_PROVIDER *EVP_ASYM_CIPHER_get0_provider(const EVP_ASYM_CIPHER *cipher);
24        void EVP_ASYM_CIPHER_do_all_provided(OSSL_LIB_CTX *libctx,
25                                             void (*fn)(EVP_ASYM_CIPHER *cipher,
26                                                        void *arg),
27                                             void *arg);
28        int EVP_ASYM_CIPHER_names_do_all(const EVP_ASYM_CIPHER *cipher,
29                                         void (*fn)(const char *name, void *data),
30                                         void *data);
31        const char *EVP_ASYM_CIPHER_get0_description(const EVP_ASYM_CIPHER *cipher);
32        const OSSL_PARAM *EVP_ASYM_CIPHER_gettable_ctx_params(const EVP_ASYM_CIPHER *cip);
33        const OSSL_PARAM *EVP_ASYM_CIPHER_settable_ctx_params(const EVP_ASYM_CIPHER *cip);
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DESCRIPTION

36       EVP_ASYM_CIPHER_fetch() fetches the implementation for the given
37       algorithm from any provider offering it, within the criteria given by
38       the properties and in the scope of the given library context ctx (see
39       OSSL_LIB_CTX(3)). The algorithm will be one offering functions for
40       performing asymmetric cipher related tasks such as asymmetric
41       encryption and decryption.  See "ALGORITHM FETCHING" in crypto(7) for
42       further information.
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44       The returned value must eventually be freed with
45       EVP_ASYM_CIPHER_free().
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47       EVP_ASYM_CIPHER_free() decrements the reference count for the
48       EVP_ASYM_CIPHER structure. Typically this structure will have been
49       obtained from an earlier call to EVP_ASYM_CIPHER_fetch(). If the
50       reference count drops to 0 then the structure is freed.
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52       EVP_ASYM_CIPHER_up_ref() increments the reference count for an
53       EVP_ASYM_CIPHER structure.
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55       EVP_ASYM_CIPHER_is_a() returns 1 if cipher is an implementation of an
56       algorithm that's identifiable with name, otherwise 0.
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58       EVP_ASYM_CIPHER_get0_provider() returns the provider that cipher was
59       fetched from.
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61       EVP_ASYM_CIPHER_do_all_provided() traverses all EVP_ASYM_CIPHERs
62       implemented by all activated providers in the given library context
63       libctx, and for each of the implementations, calls the given function
64       fn with the implementation method and the given arg as argument.
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66       EVP_ASYM_CIPHER_get0_name() returns the algorithm name from the
67       provided implementation for the given cipher. Note that the cipher may
68       have multiple synonyms associated with it. In this case the first name
69       from the algorithm definition is returned. Ownership of the returned
70       string is retained by the cipher object and should not be freed by the
71       caller.
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73       EVP_ASYM_CIPHER_names_do_all() traverses all names for cipher, and
74       calls fn with each name and data.
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76       EVP_ASYM_CIPHER_get0_description() returns a description of the cipher,
77       meant for display and human consumption.  The description is at the
78       discretion of the cipher implementation.
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80       EVP_ASYM_CIPHER_gettable_ctx_params() and
81       EVP_ASYM_CIPHER_settable_ctx_params() return a constant OSSL_PARAM
82       array that describes the names and types of key parameters that can be
83       retrieved or set by a key encryption algorithm using
84       EVP_PKEY_CTX_get_params(3) and EVP_PKEY_CTX_set_params(3).
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RETURN VALUES

87       EVP_ASYM_CIPHER_fetch() returns a pointer to an EVP_ASYM_CIPHER for
88       success or NULL for failure.
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90       EVP_ASYM_CIPHER_up_ref() returns 1 for success or 0 otherwise.
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92       EVP_ASYM_CIPHER_names_do_all() returns 1 if the callback was called for
93       all names. A return value of 0 means that the callback was not called
94       for any names.
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96       EVP_ASYM_CIPHER_gettable_ctx_params() and
97       EVP_ASYM_CIPHER_settable_ctx_params() return a constant OSSL_PARAM
98       array or NULL on error.
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SEE ALSO

101       "ALGORITHM FETCHING" in crypto(7), OSSL_PROVIDER(3)
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HISTORY

104       The functions described here were added in OpenSSL 3.0.
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107       Copyright 2019-2021 The OpenSSL Project Authors. All Rights Reserved.
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109       Licensed under the Apache License 2.0 (the "License").  You may not use
110       this file except in compliance with the License.  You can obtain a copy
111       in the file LICENSE in the source distribution or at
112       <https://www.openssl.org/source/license.html>.
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1163.0.5                             2022-07-05       EVP_ASYM_CIPHER_FREE(3ossl)
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