5 provider-storemgmt - The OSSL_STORE library E<lt>-E<gt> provider functions
9 #include <openssl/core_dispatch.h>
12 * None of these are actual functions, but are displayed like this for
13 * the function signatures for functions that are offered as function
14 * pointers in OSSL_DISPATCH arrays.
17 void *OSSL_FUNC_store_open(void *provctx, const char *uri);
18 void *OSSL_FUNC_store_attach(void *provctx, OSSL_CORE_BIO *bio);
19 const OSSL_PARAM *store_settable_ctx_params(void *provctx);
20 int OSSL_FUNC_store_set_ctx_params(void *loaderctx, const OSSL_PARAM[]);
21 int OSSL_FUNC_store_load(void *loaderctx,
22 OSSL_CALLBACK *object_cb, void *object_cbarg,
23 OSSL_PASSPHRASE_CALLBACK *pw_cb, void *pw_cbarg);
24 int OSSL_FUNC_store_eof(void *loaderctx);
25 int OSSL_FUNC_store_close(void *loaderctx);
27 int OSSL_FUNC_store_export_object
28 (void *loaderctx, const void *objref, size_t objref_sz,
29 OSSL_CALLBACK *export_cb, void *export_cbarg);
33 The STORE operation is the provider side of the L<ossl_store(7)> API.
35 The primary responsibility of the STORE operation is to load all sorts
36 of objects from a container indicated by URI. These objects are given
37 to the OpenSSL library in provider-native object abstraction form (see
38 L<provider-object(7)>). The OpenSSL library is then responsible for
39 passing on that abstraction to suitable provided functions.
41 Examples of functions that the OpenSSL library can pass the abstraction to
42 include OSSL_FUNC_keymgmt_load() (L<provider-keymgmt(7)>),
43 OSSL_FUNC_store_export_object() (which exports the object in parameterized
46 All "functions" mentioned here are passed as function pointers between
47 F<libcrypto> and the provider in B<OSSL_DISPATCH> arrays via
48 B<OSSL_ALGORITHM> arrays that are returned by the provider's
49 provider_query_operation() function
50 (see L<provider-base(7)/Provider Functions>).
52 All these "functions" have a corresponding function type definition named
53 B<OSSL_{name}_fn>, and a helper function to retrieve the function pointer
54 from a B<OSSL_DISPATCH> element named B<OSSL_get_{name}>.
55 For example, the "function" OSSL_FUNC_store_load() has these:
57 typedef void *(OSSL_OSSL_FUNC_store_load_fn)(void *provctx,
58 const OSSL_PARAM params[]);
59 static ossl_inline OSSL_OSSL_FUNC_store_load_fn
60 OSSL_OSSL_FUNC_store_load(const OSSL_DISPATCH *opf);
62 B<OSSL_DISPATCH> arrays are indexed by numbers that are provided as macros
63 in L<openssl-core_dispatch.h(7)>, as follows:
65 OSSL_FUNC_store_open OSSL_FUNC_STORE_OPEN
66 OSSL_FUNC_store_attach OSSL_FUNC_STORE_ATTACH
67 OSSL_FUNC_store_settable_ctx_params OSSL_FUNC_STORE_SETTABLE_CTX_PARAMS
68 OSSL_FUNC_store_set_ctx_params OSSL_FUNC_STORE_SET_CTX_PARAMS
69 OSSL_FUNC_store_load OSSL_FUNC_STORE_LOAD
70 OSSL_FUNC_store_eof OSSL_FUNC_STORE_EOF
71 OSSL_FUNC_store_close OSSL_FUNC_STORE_CLOSE
72 OSSL_FUNC_store_export_object OSSL_FUNC_STORE_EXPORT_OBJECT
76 OSSL_FUNC_store_open() should create a provider side context with data based
77 on the input I<uri>. The implementation is entirely responsible for the
78 interpretation of the URI.
80 OSSL_FUNC_store_attach() should create a provider side context with the core
81 B<BIO> I<bio> attached. This is an alternative to using a URI to find storage,
82 supporting L<OSSL_STORE_attach(3)>.
84 OSSL_FUNC_store_settable_ctx_params() should return a constant array of
85 descriptor B<OSSL_PARAM>, for parameters that OSSL_FUNC_store_set_ctx_params()
88 OSSL_FUNC_store_set_ctx_params() should set additional parameters, such as what
89 kind of data to expect, search criteria, and so on. More on those below, in
90 L</Load Parameters>. Whether unrecognised parameters are an error or simply
91 ignored is at the implementation's discretion.
92 Passing NULL for I<params> should return true.
94 OSSL_FUNC_store_load() loads the next object from the URI opened by
95 OSSL_FUNC_store_open(), creates an object abstraction for it (see
96 L<provider-object(7)>), and calls I<object_cb> with it as well as
97 I<object_cbarg>. I<object_cb> will then interpret the object abstraction
98 and do what it can to wrap it or decode it into an OpenSSL structure. In
99 case a passphrase needs to be prompted to unlock an object, I<pw_cb> should
102 OSSL_FUNC_store_eof() indicates if the end of the set of objects from the
103 URI has been reached. When that happens, there's no point trying to do any
106 OSSL_FUNC_store_close() frees the provider side context I<ctx>.
108 =head2 Load Parameters
112 =item "expect" (B<OSSL_STORE_PARAM_EXPECT>) <integer>
114 Is a hint of what type of data the OpenSSL library expects to get.
115 This is only useful for optimization, as the library will check that the
116 object types match the expectation too.
118 The number that can be given through this parameter is found in
119 F<< <openssl/store.h> >>, with the macros having names starting with
120 C<OSSL_STORE_INFO_>. These are further described in
121 L<OSSL_STORE_INFO(3)/SUPPORTED OBJECTS>.
123 =item "subject" (B<OSSL_STORE_PARAM_SUBJECT>) <octet string>
125 Indicates that the caller wants to search for an object with the given
126 subject associated. This can be used to select specific certificates
129 The contents of the octet string is expected to be in DER form.
131 =item "issuer" (B<OSSL_STORE_PARAM_ISSUER>) <octet string>
133 Indicates that the caller wants to search for an object with the given
134 issuer associated. This can be used to select specific certificates
137 The contents of the octet string is expected to be in DER form.
139 =item "serial" (B<OSSL_STORE_PARAM_SERIAL>) <integer>
141 Indicates that the caller wants to search for an object with the given
142 serial number associated.
144 =item "digest" (B<OSSL_STORE_PARAM_DIGEST>) <utf8 string>
146 =item "fingerprint" (B<OSSL_STORE_PARAM_FINGERPRINT>) <octet string>
148 Indicates that the caller wants to search for an object with the given
149 fingerprint, computed with the given digest.
151 =item "alias" (B<OSSL_STORE_PARAM_ALIAS>) <utf8 string>
153 Indicates that the caller wants to search for an object with the given
154 alias (some call it a "friendly name").
158 Several of these search criteria may be combined. For example, to
159 search for a certificate by issuer+serial, both the "issuer" and the
160 "serial" parameters will be given.
168 The STORE interface was introduced in OpenSSL 3.0.
172 Copyright 2020 The OpenSSL Project Authors. All Rights Reserved.
174 Licensed under the Apache License 2.0 (the "License"). You may not use
175 this file except in compliance with the License. You can obtain a copy
176 in the file LICENSE in the source distribution or at
177 L<https://www.openssl.org/source/license.html>.