5 EVP_KEM_fetch, EVP_KEM_free, EVP_KEM_up_ref,
6 EVP_KEM_get0_name, EVP_KEM_is_a, EVP_KEM_get0_provider,
7 EVP_KEM_do_all_provided, EVP_KEM_names_do_all, EVP_KEM_get0_description,
8 EVP_KEM_gettable_ctx_params, EVP_KEM_settable_ctx_params
9 - Functions to manage EVP_KEM algorithm objects
13 #include <openssl/evp.h>
15 EVP_KEM *EVP_KEM_fetch(OSSL_LIB_CTX *ctx, const char *algorithm,
16 const char *properties);
17 void EVP_KEM_free(EVP_KEM *kem);
18 int EVP_KEM_up_ref(EVP_KEM *kem);
19 const char *EVP_KEM_get0_name(const EVP_KEM *kem);
20 int EVP_KEM_is_a(const EVP_KEM *kem, const char *name);
21 OSSL_PROVIDER *EVP_KEM_get0_provider(const EVP_KEM *kem);
22 void EVP_KEM_do_all_provided(OSSL_LIB_CTX *libctx,
23 void (*fn)(EVP_KEM *kem, void *arg), void *arg);
24 int EVP_KEM_names_do_all(const EVP_KEM *kem,
25 void (*fn)(const char *name, void *data), void *data);
26 const char *EVP_KEM_get0_description(const EVP_KEM *kem);
27 const OSSL_PARAM *EVP_KEM_gettable_ctx_params(const EVP_KEM *kem);
28 const OSSL_PARAM *EVP_KEM_settable_ctx_params(const EVP_KEM *kem);
32 EVP_KEM_fetch() fetches the implementation for the given B<algorithm> from any
33 provider offering it, within the criteria given by the B<properties> and in the
34 scope of the given library context B<ctx> (see L<OSSL_LIB_CTX(3)>). The algorithm
35 will be one offering functions for performing asymmetric kem related tasks such
36 as key encapsulation and decapsulation.
37 See L<crypto(7)/ALGORITHM FETCHING> for further information.
39 The returned value must eventually be freed with EVP_KEM_free().
41 EVP_KEM_free() decrements the reference count for the B<EVP_KEM> structure.
42 Typically this structure will have been obtained from an earlier call to
43 EVP_KEM_fetch(). If the reference count drops to 0 then the structure is freed.
45 EVP_KEM_up_ref() increments the reference count for an B<EVP_KEM> structure.
47 EVP_KEM_is_a() returns 1 if I<kem> is an implementation of an
48 algorithm that's identifiable with I<name>, otherwise 0.
50 EVP_KEM_get0_provider() returns the provider that I<kem> was fetched from.
52 EVP_KEM_do_all_provided() traverses all EVP_KEMs implemented by all activated
53 providers in the given library context I<libctx>, and for each of the
54 implementations, calls the given function I<fn> with the implementation method
55 and the given I<arg> as argument.
57 EVP_KEM_get0_name() returns the algorithm name from the provided
58 implementation for the given I<kem>. Note that the I<kem> may have
59 multiple synonyms associated with it. In this case the first name from the
60 algorithm definition is returned. Ownership of the returned string is retained
61 by the I<kem> object and should not be freed by the caller.
63 EVP_KEM_names_do_all() traverses all names for I<kem>, and calls I<fn> with
64 each name and I<data>.
66 EVP_KEM_get0_description() returns a description of the I<kem>, meant for
67 display and human consumption. The description is at the discretion of
68 the I<kem> implementation.
70 EVP_KEM_gettable_ctx_params() and EVP_KEM_settable_ctx_params() return
71 a constant B<OSSL_PARAM> array that describes the names and types of key
72 parameters that can be retrieved or set by a key encapsulation algorithm using
73 L<EVP_PKEY_CTX_get_params(3)> and L<EVP_PKEY_CTX_set_params(3)>.
77 EVP_KEM_fetch() returns a pointer to an B<EVP_KEM> for success or B<NULL> for
80 EVP_KEM_up_ref() returns 1 for success or 0 otherwise.
82 EVP_KEM_names_do_all() returns 1 if the callback was called for all names. A
83 return value of 0 means that the callback was not called for any names.
85 EVP_KEM_gettable_ctx_params() and EVP_KEM_settable_ctx_params() return
86 a constant B<OSSL_PARAM> array or NULL on error.
90 L<crypto(7)/ALGORITHM FETCHING>, L<OSSL_PROVIDER(3)>
94 The functions described here were added in OpenSSL 3.0.
98 Copyright 2020-2021 The OpenSSL Project Authors. All Rights Reserved.
100 Licensed under the Apache License 2.0 (the "License"). You may not use
101 this file except in compliance with the License. You can obtain a copy
102 in the file LICENSE in the source distribution or at
103 L<https://www.openssl.org/source/license.html>.