6 EVP_SIGNATURE_fetch, EVP_SIGNATURE_free, EVP_SIGNATURE_up_ref,
7 EVP_SIGNATURE_is_a, EVP_SIGNATURE_get0_provider,
8 EVP_SIGNATURE_do_all_provided, EVP_SIGNATURE_names_do_all,
9 EVP_SIGNATURE_get0_name, EVP_SIGNATURE_get0_description,
10 EVP_SIGNATURE_gettable_ctx_params, EVP_SIGNATURE_settable_ctx_params
11 - Functions to manage EVP_SIGNATURE algorithm objects
15 #include <openssl/evp.h>
17 typedef struct evp_signature_st EVP_SIGNATURE;
19 EVP_SIGNATURE *EVP_SIGNATURE_fetch(OSSL_LIB_CTX *ctx, const char *algorithm,
20 const char *properties);
21 void EVP_SIGNATURE_free(EVP_SIGNATURE *signature);
22 int EVP_SIGNATURE_up_ref(EVP_SIGNATURE *signature);
23 const char *EVP_SIGNATURE_get0_name(const EVP_SIGNATURE *signature);
24 int EVP_SIGNATURE_is_a(const EVP_SIGNATURE *signature, const char *name);
25 OSSL_PROVIDER *EVP_SIGNATURE_get0_provider(const EVP_SIGNATURE *signature);
26 void EVP_SIGNATURE_do_all_provided(OSSL_LIB_CTX *libctx,
27 void (*fn)(EVP_SIGNATURE *signature,
30 int EVP_SIGNATURE_names_do_all(const EVP_SIGNATURE *signature,
31 void (*fn)(const char *name, void *data),
33 const char *EVP_SIGNATURE_get0_name(const EVP_SIGNATURE *signature);
34 const char *EVP_SIGNATURE_get0_description(const EVP_SIGNATURE *signature);
35 const OSSL_PARAM *EVP_SIGNATURE_gettable_ctx_params(const EVP_SIGNATURE *sig);
36 const OSSL_PARAM *EVP_SIGNATURE_settable_ctx_params(const EVP_SIGNATURE *sig);
40 EVP_SIGNATURE_fetch() fetches the implementation for the given
41 B<algorithm> from any provider offering it, within the criteria given
43 The algorithm will be one offering functions for performing signature related
44 tasks such as signing and verifying.
45 See L<crypto(7)/ALGORITHM FETCHING> for further information.
47 The returned value must eventually be freed with EVP_SIGNATURE_free().
49 EVP_SIGNATURE_free() decrements the reference count for the B<EVP_SIGNATURE>
50 structure. Typically this structure will have been obtained from an earlier call
51 to EVP_SIGNATURE_fetch(). If the reference count drops to 0 then the
54 EVP_SIGNATURE_up_ref() increments the reference count for an B<EVP_SIGNATURE>
57 EVP_SIGNATURE_is_a() returns 1 if I<signature> is an implementation of an
58 algorithm that's identifiable with I<name>, otherwise 0.
60 EVP_SIGNATURE_get0_provider() returns the provider that I<signature> was
63 EVP_SIGNATURE_do_all_provided() traverses all SIGNATURE implemented by all
64 activated roviders in the given library context I<libctx>, and for each of the
65 implementations, calls the given function I<fn> with the implementation method
66 and the given I<arg> as argument.
68 EVP_SIGNATURE_get0_name() returns the algorithm name from the provided
69 implementation for the given I<signature>. Note that the I<signature> may have
70 multiple synonyms associated with it. In this case the first name from the
71 algorithm definition is returned. Ownership of the returned string is retained
72 by the I<signature> object and should not be freed by the caller.
74 EVP_SIGNATURE_names_do_all() traverses all names for I<signature>, and calls
75 I<fn> with each name and I<data>.
77 EVP_SIGNATURE_get0_description() returns a description of the I<signature>,
78 meant for display and human consumption. The description is at the
79 discretion of the I<signature> implementation.
81 EVP_SIGNATURE_gettable_ctx_params() and EVP_SIGNATURE_settable_ctx_params()
82 return a constant B<OSSL_PARAM> array that describes the names and types of key
83 parameters that can be retrieved or set by a signature algorithm using
84 L<EVP_PKEY_CTX_get_params(3)> and L<EVP_PKEY_CTX_set_params(3)>.
88 EVP_SIGNATURE_fetch() returns a pointer to an B<EVP_SIGNATURE> for success
89 or B<NULL> for failure.
91 EVP_SIGNATURE_up_ref() returns 1 for success or 0 otherwise.
93 EVP_SIGNATURE_names_do_all() returns 1 if the callback was called for all names.
94 A return value of 0 means that the callback was not called for any names.
96 EVP_SIGNATURE_gettable_ctx_params() and EVP_SIGNATURE_settable_ctx_params()
97 return a constant B<OSSL_PARAM> array or NULL on error.
101 L<crypto(7)/ALGORITHM FETCHING>, L<OSSL_PROVIDER(3)>
105 The functions described here were added in OpenSSL 3.0.
109 Copyright 2019-2021 The OpenSSL Project Authors. All Rights Reserved.
111 Licensed under the Apache License 2.0 (the "License"). You may not use
112 this file except in compliance with the License. You can obtain a copy
113 in the file LICENSE in the source distribution or at
114 L<https://www.openssl.org/source/license.html>.