Provided by: libssl-doc_3.0.5-2ubuntu1_all 
NAME
OSSL_STORE_LOADER, OSSL_STORE_LOADER_fetch, OSSL_STORE_LOADER_up_ref,
OSSL_STORE_LOADER_free, OSSL_STORE_LOADER_get0_provider,
OSSL_STORE_LOADER_get0_properties, OSSL_STORE_LOADER_is_a,
OSSL_STORE_LOADER_get0_description, OSSL_STORE_LOADER_do_all_provided,
OSSL_STORE_LOADER_names_do_all, OSSL_STORE_LOADER_CTX, OSSL_STORE_LOADER_new,
OSSL_STORE_LOADER_get0_engine, OSSL_STORE_LOADER_get0_scheme, OSSL_STORE_LOADER_set_open,
OSSL_STORE_LOADER_set_open_ex, OSSL_STORE_LOADER_set_attach, OSSL_STORE_LOADER_set_ctrl,
OSSL_STORE_LOADER_set_expect, OSSL_STORE_LOADER_set_find, OSSL_STORE_LOADER_set_load,
OSSL_STORE_LOADER_set_eof, OSSL_STORE_LOADER_set_error, OSSL_STORE_LOADER_set_close,
OSSL_STORE_register_loader, OSSL_STORE_unregister_loader, OSSL_STORE_open_fn,
OSSL_STORE_open_ex_fn, OSSL_STORE_attach_fn, OSSL_STORE_ctrl_fn, OSSL_STORE_expect_fn,
OSSL_STORE_find_fn, OSSL_STORE_load_fn, OSSL_STORE_eof_fn, OSSL_STORE_error_fn,
OSSL_STORE_close_fn - Types and functions to manipulate, register and unregister STORE
loaders for different URI schemes
SYNOPSIS
#include <openssl/store.h>
typedef struct ossl_store_loader_st OSSL_STORE_LOADER;
OSSL_STORE_LOADER *OSSL_STORE_LOADER_fetch(OSSL_LIB_CTX *libctx,
const char *scheme,
const char *properties);
int OSSL_STORE_LOADER_up_ref(OSSL_STORE_LOADER *loader);
void OSSL_STORE_LOADER_free(OSSL_STORE_LOADER *loader);
const OSSL_PROVIDER *OSSL_STORE_LOADER_get0_provider(const OSSL_STORE_LOADER *
loader);
const char *OSSL_STORE_LOADER_get0_properties(const OSSL_STORE_LOADER *loader);
const char *OSSL_STORE_LOADER_get0_description(const OSSL_STORE_LOADER *loader);
int OSSL_STORE_LOADER_is_a(const OSSL_STORE_LOADER *loader,
const char *scheme);
void OSSL_STORE_LOADER_do_all_provided(OSSL_LIB_CTX *libctx,
void (*user_fn)(OSSL_STORE_LOADER *loader,
void *arg),
void *user_arg);
int OSSL_STORE_LOADER_names_do_all(const OSSL_STORE_LOADER *loader,
void (*fn)(const char *name, void *data),
void *data);
The following functions have been deprecated since OpenSSL 3.0, and can be hidden entirely
by defining OPENSSL_API_COMPAT with a suitable version value, see openssl_user_macros(7):
OSSL_STORE_LOADER *OSSL_STORE_LOADER_new(ENGINE *e, const char *scheme);
const ENGINE *OSSL_STORE_LOADER_get0_engine(const OSSL_STORE_LOADER
*store_loader);
const char *OSSL_STORE_LOADER_get0_scheme(const OSSL_STORE_LOADER
*store_loader);
/* struct ossl_store_loader_ctx_st is defined differently by each loader */
typedef struct ossl_store_loader_ctx_st OSSL_STORE_LOADER_CTX;
typedef OSSL_STORE_LOADER_CTX *(*OSSL_STORE_open_fn)(
const char *uri, const UI_METHOD *ui_method, void *ui_data);
int OSSL_STORE_LOADER_set_open(OSSL_STORE_LOADER *store_loader,
OSSL_STORE_open_fn store_open_function);
typedef OSSL_STORE_LOADER_CTX *(*OSSL_STORE_open_ex_fn)(
const char *uri, const UI_METHOD *ui_method, void *ui_data);
int OSSL_STORE_LOADER_set_open_ex
(OSSL_STORE_LOADER *store_loader,
OSSL_STORE_open_ex_fn store_open_ex_function);
typedef OSSL_STORE_LOADER_CTX *(*OSSL_STORE_attach_fn)
(const OSSL_STORE_LOADER *loader, BIO *bio,
OSSL_LIB_CTX *libctx, const char *propq,
const UI_METHOD *ui_method, void *ui_data);
int OSSL_STORE_LOADER_set_attach(OSSL_STORE_LOADER *loader,
OSSL_STORE_attach_fn attach_function);
typedef int (*OSSL_STORE_ctrl_fn)(OSSL_STORE_LOADER_CTX *ctx, int cmd,
va_list args);
int OSSL_STORE_LOADER_set_ctrl(OSSL_STORE_LOADER *store_loader,
OSSL_STORE_ctrl_fn store_ctrl_function);
typedef int (*OSSL_STORE_expect_fn)(OSSL_STORE_LOADER_CTX *ctx, int expected);
int OSSL_STORE_LOADER_set_expect(OSSL_STORE_LOADER *loader,
OSSL_STORE_expect_fn expect_function);
typedef int (*OSSL_STORE_find_fn)(OSSL_STORE_LOADER_CTX *ctx,
OSSL_STORE_SEARCH *criteria);
int OSSL_STORE_LOADER_set_find(OSSL_STORE_LOADER *loader,
OSSL_STORE_find_fn find_function);
typedef OSSL_STORE_INFO *(*OSSL_STORE_load_fn)(OSSL_STORE_LOADER_CTX *ctx,
UI_METHOD *ui_method,
void *ui_data);
int OSSL_STORE_LOADER_set_load(OSSL_STORE_LOADER *store_loader,
OSSL_STORE_load_fn store_load_function);
typedef int (*OSSL_STORE_eof_fn)(OSSL_STORE_LOADER_CTX *ctx);
int OSSL_STORE_LOADER_set_eof(OSSL_STORE_LOADER *store_loader,
OSSL_STORE_eof_fn store_eof_function);
typedef int (*OSSL_STORE_error_fn)(OSSL_STORE_LOADER_CTX *ctx);
int OSSL_STORE_LOADER_set_error(OSSL_STORE_LOADER *store_loader,
OSSL_STORE_error_fn store_error_function);
typedef int (*OSSL_STORE_close_fn)(OSSL_STORE_LOADER_CTX *ctx);
int OSSL_STORE_LOADER_set_close(OSSL_STORE_LOADER *store_loader,
OSSL_STORE_close_fn store_close_function);
void OSSL_STORE_LOADER_free(OSSL_STORE_LOADER *store_loader);
int OSSL_STORE_register_loader(OSSL_STORE_LOADER *loader);
OSSL_STORE_LOADER *OSSL_STORE_unregister_loader(const char *scheme);
DESCRIPTION
OSSL_STORE_LOADER is a method for OSSL_STORE loaders, which implement OSSL_STORE_open(),
OSSL_STORE_open_ex(), OSSL_STORE_load(), OSSL_STORE_eof(), OSSL_STORE_error() and
OSSL_STORE_close() for specific storage schemes.
OSSL_STORE_LOADER_fetch() looks for an implementation for a storage scheme within the
providers that has been loaded into the OSSL_LIB_CTX given by libctx, and with the
properties given by properties.
OSSL_STORE_LOADER_up_ref() increments the reference count for the given loader.
OSSL_STORE_LOADER_free() decrements the reference count for the given loader, and when the
count reaches zero, frees it.
OSSL_STORE_LOADER_get0_provider() returns the provider of the given loader.
OSSL_STORE_LOADER_get0_properties() returns the property definition associated with the
given loader.
OSSL_STORE_LOADER_is_a() checks if loader is an implementation of an algorithm that's
identifiable with scheme.
OSSL_STORE_LOADER_get0_description() returns a description of the loader, meant for
display and human consumption. The description is at the discretion of the loader
implementation.
OSSL_STORE_LOADER_do_all_provided() traverses all store implementations by all activated
providers in the library context libctx, and for each of the implementations, calls
user_fn with the implementation method and user_arg as arguments.
OSSL_STORE_LOADER_names_do_all() traverses all names for the given loader, and calls fn
with each name and data.
Legacy Types and Functions (deprecated)
These functions help applications and engines to create loaders for schemes they support.
These are all deprecated and discouraged in favour of provider implementations, see
provider-storemgmt(7).
OSSL_STORE_LOADER_CTX is a type template, to be defined by each loader using "struct
ossl_store_loader_ctx_st { ... }".
OSSL_STORE_open_fn, OSSL_STORE_open_ex_fn, OSSL_STORE_ctrl_fn, OSSL_STORE_expect_fn,
OSSL_STORE_find_fn, OSSL_STORE_load_fn, OSSL_STORE_eof_fn, and OSSL_STORE_close_fn are the
function pointer types used within a STORE loader. The functions pointed at define the
functionality of the given loader.
OSSL_STORE_open_fn and OSSL_STORE_open_ex_fn
OSSL_STORE_open_ex_fn takes a URI and is expected to interpret it in the best manner
possible according to the scheme the loader implements. It also takes a UI_METHOD and
associated data, to be used any time something needs to be prompted for, as well as a
library context libctx with an associated property query propq, to be used when
fetching necessary algorithms to perform the loads. Furthermore, this function is
expected to initialize what needs to be initialized, to create a private data store
(OSSL_STORE_LOADER_CTX, see above), and to return it. If something goes wrong, this
function is expected to return NULL.
OSSL_STORE_open_fn does the same thing as OSSL_STORE_open_ex_fn but uses NULL for the
library context libctx and property query propq.
OSSL_STORE_attach_fn
This function takes a BIO, otherwise works like OSSL_STORE_open_ex_fn.
OSSL_STORE_ctrl_fn
This function takes a OSSL_STORE_LOADER_CTX pointer, a command number cmd and a
va_list args and is used to manipulate loader specific parameters.
Loader specific command numbers must begin at OSSL_STORE_C_CUSTOM_START. Any number
below that is reserved for future globally known command numbers.
This function is expected to return 1 on success, 0 on error.
OSSL_STORE_expect_fn
This function takes a OSSL_STORE_LOADER_CTX pointer and a OSSL_STORE_INFO identity
expected, and is used to tell the loader what object type is expected. expected may
be zero to signify that no specific object type is expected.
This function is expected to return 1 on success, 0 on error.
OSSL_STORE_find_fn
This function takes a OSSL_STORE_LOADER_CTX pointer and a OSSL_STORE_SEARCH search
criterion, and is used to tell the loader what to search for.
When called with the loader context being NULL, this function is expected to return 1
if the loader supports the criterion, otherwise 0.
When called with the loader context being something other than NULL, this function is
expected to return 1 on success, 0 on error.
OSSL_STORE_load_fn
This function takes a OSSL_STORE_LOADER_CTX pointer and a UI_METHOD with associated
data. It's expected to load the next available data, mold it into a data structure
that can be wrapped in a OSSL_STORE_INFO using one of the OSSL_STORE_INFO(3)
functions. If no more data is available or an error occurs, this function is expected
to return NULL. The OSSL_STORE_eof_fn and OSSL_STORE_error_fn functions must indicate
if it was in fact the end of data or if an error occurred.
Note that this function retrieves one data item only.
OSSL_STORE_eof_fn
This function takes a OSSL_STORE_LOADER_CTX pointer and is expected to return 1 to
indicate that the end of available data has been reached. It is otherwise expected to
return 0.
OSSL_STORE_error_fn
This function takes a OSSL_STORE_LOADER_CTX pointer and is expected to return 1 to
indicate that an error occurred in a previous call to the OSSL_STORE_load_fn function.
It is otherwise expected to return 0.
OSSL_STORE_close_fn
This function takes a OSSL_STORE_LOADER_CTX pointer and is expected to close or shut
down what needs to be closed, and finally free the contents of the
OSSL_STORE_LOADER_CTX pointer. It returns 1 on success and 0 on error.
OSSL_STORE_LOADER_new() creates a new OSSL_STORE_LOADER. It takes an ENGINE e and a
string scheme. scheme must always be set. Both e and scheme are used as is and must
therefore be alive as long as the created loader is.
OSSL_STORE_LOADER_get0_engine() returns the engine of the store_loader.
OSSL_STORE_LOADER_get0_scheme() returns the scheme of the store_loader.
OSSL_STORE_LOADER_set_open() sets the opener function for the store_loader.
OSSL_STORE_LOADER_set_open_ex() sets the opener with library context function for the
store_loader.
OSSL_STORE_LOADER_set_attach() sets the attacher function for the store_loader.
OSSL_STORE_LOADER_set_ctrl() sets the control function for the store_loader.
OSSL_STORE_LOADER_set_expect() sets the expect function for the store_loader.
OSSL_STORE_LOADER_set_load() sets the loader function for the store_loader.
OSSL_STORE_LOADER_set_eof() sets the end of file checker function for the store_loader.
OSSL_STORE_LOADER_set_close() sets the closing function for the store_loader.
OSSL_STORE_LOADER_free() frees the given store_loader.
OSSL_STORE_register_loader() register the given store_loader and thereby makes it
available for use with OSSL_STORE_open(), OSSL_STORE_open_ex(), OSSL_STORE_load(),
OSSL_STORE_eof() and OSSL_STORE_close().
OSSL_STORE_unregister_loader() unregister the store loader for the given scheme.
RETURN VALUES
OSSL_STORE_LOADER_fetch() returns a pointer to an OSSL_STORE_LOADER object, or NULL on
error.
OSSL_STORE_LOADER_up_ref() returns 1 on success, or 0 on error.
OSSL_STORE_LOADER_names_do_all() returns 1 if the callback was called for all names. A
return value of 0 means that the callback was not called for any names.
OSSL_STORE_LOADER_free() doesn't return any value.
OSSL_STORE_LOADER_get0_provider() returns a pointer to a provider object, or NULL on
error.
OSSL_STORE_LOADER_get0_properties() returns a pointer to a property definition string, or
NULL on error.
OSSL_STORE_LOADER_is_a() returns 1 if loader was identifiable, otherwise 0.
OSSL_STORE_LOADER_get0_description() returns a pointer to a decription, or NULL if there
isn't one.
The functions with the types OSSL_STORE_open_fn, OSSL_STORE_open_ex_fn,
OSSL_STORE_ctrl_fn, OSSL_STORE_expect_fn, OSSL_STORE_load_fn, OSSL_STORE_eof_fn and
OSSL_STORE_close_fn have the same return values as OSSL_STORE_open(),
OSSL_STORE_open_ex(), OSSL_STORE_ctrl(), OSSL_STORE_expect(), OSSL_STORE_load(),
OSSL_STORE_eof() and OSSL_STORE_close(), respectively.
OSSL_STORE_LOADER_new() returns a pointer to a OSSL_STORE_LOADER on success, or NULL on
failure.
OSSL_STORE_LOADER_set_open(), OSSL_STORE_LOADER_set_open_ex(),
OSSL_STORE_LOADER_set_ctrl(), OSSL_STORE_LOADER_set_load(), OSSL_STORE_LOADER_set_eof()
and OSSL_STORE_LOADER_set_close() return 1 on success, or 0 on failure.
OSSL_STORE_register_loader() returns 1 on success, or 0 on failure.
OSSL_STORE_unregister_loader() returns the unregistered loader on success, or NULL on
failure.
SEE ALSO
ossl_store(7), OSSL_STORE_open(3), OSSL_LIB_CTX(3), provider-storemgmt(7)
HISTORY
OSSL_STORE_LOADER_fetch(), OSSL_STORE_LOADER_up_ref(), OSSL_STORE_LOADER_free(),
OSSL_STORE_LOADER_get0_provider(), OSSL_STORE_LOADER_get0_properties(),
OSSL_STORE_LOADER_is_a(), OSSL_STORE_LOADER_do_all_provided() and
OSSL_STORE_LOADER_names_do_all() were added in OpenSSL 3.0.
OSSL_STORE_open_ex_fn() was added in OpenSSL 3.0.
OSSL_STORE_LOADER, OSSL_STORE_LOADER_CTX, OSSL_STORE_LOADER_new(),
OSSL_STORE_LOADER_set0_scheme(), OSSL_STORE_LOADER_get0_scheme(),
OSSL_STORE_LOADER_get0_engine(), OSSL_STORE_LOADER_set_expect(),
OSSL_STORE_LOADER_set_find(), OSSL_STORE_LOADER_set_attach(),
OSSL_STORE_LOADER_set_open_ex(), OSSL_STORE_LOADER_set_open(),
OSSL_STORE_LOADER_set_ctrl(), OSSL_STORE_LOADER_set_load(), OSSL_STORE_LOADER_set_eof(),
OSSL_STORE_LOADER_set_close(), OSSL_STORE_LOADER_free(), OSSL_STORE_register_loader(),
OSSL_STORE_LOADER_set_error(), OSSL_STORE_unregister_loader(), OSSL_STORE_open_fn(),
OSSL_STORE_ctrl_fn(), OSSL_STORE_load_fn(), OSSL_STORE_eof_fn() and OSSL_STORE_close_fn()
were added in OpenSSL 1.1.1, and became deprecated in OpenSSL 3.0.
COPYRIGHT
Copyright 2016-2021 The OpenSSL Project Authors. All Rights Reserved.
Licensed under the Apache License 2.0 (the "License"). You may not use this file except
in compliance with the License. You can obtain a copy in the file LICENSE in the source
distribution or at <https://www.openssl.org/source/license.html>.