1OSSL_STORE_OPEN(3ossl) OpenSSL OSSL_STORE_OPEN(3ossl)
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6 OSSL_STORE_CTX, OSSL_STORE_post_process_info_fn, OSSL_STORE_open,
7 OSSL_STORE_open_ex, OSSL_STORE_ctrl, OSSL_STORE_load, OSSL_STORE_eof,
8 OSSL_STORE_error, OSSL_STORE_close - Types and functions to read
9 objects from a URI
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12 #include <openssl/store.h>
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14 typedef struct ossl_store_ctx_st OSSL_STORE_CTX;
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16 typedef OSSL_STORE_INFO *(*OSSL_STORE_post_process_info_fn)(OSSL_STORE_INFO *,
17 void *);
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19 OSSL_STORE_CTX *OSSL_STORE_open(const char *uri, const UI_METHOD *ui_method,
20 void *ui_data,
21 OSSL_STORE_post_process_info_fn post_process,
22 void *post_process_data);
23 OSSL_STORE_CTX *
24 OSSL_STORE_open_ex(const char *uri, OSSL_LIB_CTX *libctx, const char *propq,
25 const UI_METHOD *ui_method, void *ui_data,
26 const OSSL_PARAM params[],
27 OSSL_STORE_post_process_info_fn post_process,
28 void *post_process_data);
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30 OSSL_STORE_INFO *OSSL_STORE_load(OSSL_STORE_CTX *ctx);
31 int OSSL_STORE_eof(OSSL_STORE_CTX *ctx);
32 int OSSL_STORE_error(OSSL_STORE_CTX *ctx);
33 int OSSL_STORE_close(OSSL_STORE_CTX *ctx);
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35 The following function has been deprecated since OpenSSL 3.0, and can
36 be hidden entirely by defining OPENSSL_API_COMPAT with a suitable
37 version value, see openssl_user_macros(7):
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39 int OSSL_STORE_ctrl(OSSL_STORE_CTX *ctx, int cmd, ... /* args */);
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42 These functions help the application to fetch supported objects (see
43 "SUPPORTED OBJECTS" in OSSL_STORE_INFO(3) for information on which
44 those are) from a given URI. The general method to do so is to "open"
45 the URI using OSSL_STORE_open(), read each available and supported
46 object using OSSL_STORE_load() as long as OSSL_STORE_eof() hasn't been
47 reached, and finish it off with OSSL_STORE_close().
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49 The retrieved information is stored in a OSSL_STORE_INFO, which is
50 further described in OSSL_STORE_INFO(3).
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52 Types
53 OSSL_STORE_CTX is a context variable that holds all the internal
54 information for OSSL_STORE_open(), OSSL_STORE_open_ex(),
55 OSSL_STORE_load(), OSSL_STORE_eof() and OSSL_STORE_close() to work
56 together.
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58 Functions
59 OSSL_STORE_open_ex() takes a uri or path uri, password UI method
60 ui_method with associated data ui_data, and post processing callback
61 post_process with associated data post_process_data, a library context
62 libctx with an associated property query propq, and opens a channel to
63 the data located at the URI and returns a OSSL_STORE_CTX with all
64 necessary internal information. The given ui_method and ui_data will
65 be reused by all functions that use OSSL_STORE_CTX when interaction is
66 needed, for instance to provide a password. The auxiliary
67 OSSL_PARAM(3) parameters in params can be set to further modify the
68 store operation. The given post_process and post_process_data will be
69 reused by OSSL_STORE_load() to manipulate or drop the value to be
70 returned. The post_process function drops values by returning NULL,
71 which will cause OSSL_STORE_load() to start its process over with
72 loading the next object, until post_process returns something other
73 than NULL, or the end of data is reached as indicated by
74 OSSL_STORE_eof().
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76 OSSL_STORE_open() is similar to OSSL_STORE_open_ex() but uses NULL for
77 the params, the library context libctx and property query propq.
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79 OSSL_STORE_ctrl() takes a OSSL_STORE_CTX, and command number cmd and
80 more arguments not specified here. The available loader specific
81 command numbers and arguments they each take depends on the loader
82 that's used and is documented together with that loader.
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84 There are also global controls available:
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86 OSSL_STORE_C_USE_SECMEM
87 Controls if the loader should attempt to use secure memory for any
88 allocated OSSL_STORE_INFO and its contents. This control expects
89 one argument, a pointer to an int that is expected to have the
90 value 1 (yes) or 0 (no). Any other value is an error.
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92 OSSL_STORE_load() takes a OSSL_STORE_CTX and tries to load the next
93 available object and return it wrapped with OSSL_STORE_INFO.
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95 OSSL_STORE_eof() takes a OSSL_STORE_CTX and checks if we've reached the
96 end of data.
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98 OSSL_STORE_error() takes a OSSL_STORE_CTX and checks if an error
99 occurred in the last OSSL_STORE_load() call. Note that it may still be
100 meaningful to try and load more objects, unless OSSL_STORE_eof() shows
101 that the end of data has been reached.
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103 OSSL_STORE_close() takes a OSSL_STORE_CTX, closes the channel that was
104 opened by OSSL_STORE_open() and frees all other information that was
105 stored in the OSSL_STORE_CTX, as well as the OSSL_STORE_CTX itself. If
106 ctx is NULL it does nothing.
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109 A string without a scheme prefix (that is, a non-URI string) is
110 implicitly interpreted as using the file: scheme.
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112 There are some tools that can be used together with OSSL_STORE_open()
113 to determine if any failure is caused by an unparsable URI, or if it's
114 a different error (such as memory allocation failures); if the URI was
115 parsable but the scheme unregistered, the top error will have the
116 reason "OSSL_STORE_R_UNREGISTERED_SCHEME".
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118 These functions make no direct assumption regarding the pass phrase
119 received from the password callback. The loaders may make assumptions,
120 however. For example, the file: scheme loader inherits the assumptions
121 made by OpenSSL functionality that handles the different file types;
122 this is mostly relevant for PKCS#12 objects. See
123 passphrase-encoding(7) for further information.
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126 OSSL_STORE_open() returns a pointer to a OSSL_STORE_CTX on success, or
127 NULL on failure.
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129 OSSL_STORE_load() returns a pointer to a OSSL_STORE_INFO on success, or
130 NULL on error or when end of data is reached. Use OSSL_STORE_error()
131 and OSSL_STORE_eof() to determine the meaning of a returned NULL.
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133 OSSL_STORE_eof() returns 1 if the end of data has been reached or an
134 error occurred, 0 otherwise.
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136 OSSL_STORE_error() returns 1 if an error occurred in an
137 OSSL_STORE_load() call, otherwise 0.
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139 OSSL_STORE_ctrl() and OSSL_STORE_close() returns 1 on success, or 0 on
140 failure.
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143 ossl_store(7), OSSL_STORE_INFO(3), OSSL_STORE_register_loader(3),
144 passphrase-encoding(7)
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147 OSSL_STORE_open_ex() was added in OpenSSL 3.0.
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149 OSSL_STORE_CTX, OSSL_STORE_post_process_info_fn(), OSSL_STORE_open(),
150 OSSL_STORE_ctrl(), OSSL_STORE_load(), OSSL_STORE_eof() and
151 OSSL_STORE_close() were added in OpenSSL 1.1.1.
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153 Handling of NULL ctx argument for OSSL_STORE_close() was introduced in
154 OpenSSL 1.1.1h.
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156 OSSL_STORE_open_ex() was added in OpenSSL 3.0.
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158 OSSL_STORE_ctrl() and OSSL_STORE_vctrl() were deprecated in OpenSSL
159 3.0.
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162 Copyright 2016-2021 The OpenSSL Project Authors. All Rights Reserved.
163
164 Licensed under the Apache License 2.0 (the "License"). You may not use
165 this file except in compliance with the License. You can obtain a copy
166 in the file LICENSE in the source distribution or at
167 <https://www.openssl.org/source/license.html>.
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1713.0.9 2023-07-27 OSSL_STORE_OPEN(3ossl)