| =pod |
| |
| =head1 NAME |
| |
| OSSL_STORE_LOADER, 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_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_LOADER_free, OSSL_STORE_register_loader, |
| OSSL_STORE_unregister_loader, OSSL_STORE_open_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 |
| |
| =head1 SYNOPSIS |
| |
| #include <openssl/store.h> |
| |
| typedef struct ossl_store_loader_st OSSL_STORE_LOADER; |
| |
| 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 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); |
| |
| =head1 DESCRIPTION |
| |
| These functions help applications and engines to create loaders for |
| schemes they support. |
| |
| =head2 Types |
| |
| B<OSSL_STORE_LOADER> is the type to hold a loader. |
| It contains a scheme and the functions needed to implement |
| OSSL_STORE_open(), OSSL_STORE_load(), OSSL_STORE_eof(), OSSL_STORE_error() and |
| OSSL_STORE_close() for this scheme. |
| |
| B<OSSL_STORE_LOADER_CTX> is a type template, to be defined by each loader |
| using B<struct ossl_store_loader_ctx_st { ... }>. |
| |
| B<OSSL_STORE_open_fn>, B<OSSL_STORE_ctrl_fn>, B<OSSL_STORE_expect_fn>, |
| B<OSSL_STORE_find_fn>, B<OSSL_STORE_load_fn>, B<OSSL_STORE_eof_fn>, |
| and B<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. |
| |
| =over 4 |
| |
| =item B<OSSL_STORE_open_fn> |
| |
| This function 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 B<UI_METHOD> and associated data, to be used any time |
| something needs to be prompted for. |
| Furthermore, this function is expected to initialize what needs to be |
| initialized, to create a private data store (B<OSSL_STORE_LOADER_CTX>, see |
| above), and to return it. |
| If something goes wrong, this function is expected to return NULL. |
| |
| =item B<OSSL_STORE_ctrl_fn> |
| |
| This function takes a B<OSSL_STORE_LOADER_CTX> pointer, a command number |
| B<cmd> and a B<va_list> B<args> and is used to manipulate loader |
| specific parameters. |
| |
| =begin comment |
| |
| Globally known command numbers are documented in L<OSSL_STORE_ctrl(3)>, |
| along with what B<args> are expected with each of them. |
| |
| =end comment |
| |
| Loader specific command numbers must begin at B<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. |
| |
| =item B<OSSL_STORE_expect_fn> |
| |
| This function takes a B<OSSL_STORE_LOADER_CTX> pointer and a B<OSSL_STORE_INFO> |
| identity B<expected>, and is used to tell the loader what object type is |
| expected. |
| B<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. |
| |
| =item B<OSSL_STORE_find_fn> |
| |
| This function takes a B<OSSL_STORE_LOADER_CTX> pointer and a |
| B<OSSL_STORE_SEARCH> search criterion, and is used to tell the loader what |
| to search for. |
| |
| When called with the loader context being B<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 B<NULL>, this |
| function is expected to return 1 on success, 0 on error. |
| |
| =item B<OSSL_STORE_load_fn> |
| |
| This function takes a B<OSSL_STORE_LOADER_CTX> pointer and a B<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 B<OSSL_STORE_INFO> using one of the |
| L<OSSL_STORE_INFO(3)> functions. |
| If no more data is available or an error occurs, this function is |
| expected to return NULL. |
| The B<OSSL_STORE_eof_fn> and B<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 I<one> data item only. |
| |
| =item B<OSSL_STORE_eof_fn> |
| |
| This function takes a B<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. |
| |
| =item B<OSSL_STORE_error_fn> |
| |
| This function takes a B<OSSL_STORE_LOADER_CTX> pointer and is expected to |
| return 1 to indicate that an error occurred in a previous call to the |
| B<OSSL_STORE_load_fn> function. |
| It is otherwise expected to return 0. |
| |
| =item B<OSSL_STORE_close_fn> |
| |
| This function takes a B<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 B<OSSL_STORE_LOADER_CTX> pointer. |
| It returns 1 on success and 0 on error. |
| |
| =back |
| |
| =head2 Functions |
| |
| OSSL_STORE_LOADER_new() creates a new B<OSSL_STORE_LOADER>. |
| It takes an B<ENGINE> B<e> and a string B<scheme>. |
| B<scheme> must I<always> be set. |
| Both B<e> and B<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 B<store_loader>. |
| OSSL_STORE_LOADER_get0_scheme() returns the scheme of the B<store_loader>. |
| |
| OSSL_STORE_LOADER_set_open() sets the opener function for the |
| B<store_loader>. |
| |
| OSSL_STORE_LOADER_set_ctrl() sets the control function for the |
| B<store_loader>. |
| |
| OSSL_STORE_LOADER_set_expect() sets the expect function for the |
| B<store_loader>. |
| |
| OSSL_STORE_LOADER_set_load() sets the loader function for the |
| B<store_loader>. |
| |
| OSSL_STORE_LOADER_set_eof() sets the end of file checker function for the |
| B<store_loader>. |
| |
| OSSL_STORE_LOADER_set_close() sets the closing function for the |
| B<store_loader>. |
| |
| OSSL_STORE_LOADER_free() frees the given B<store_loader>. |
| |
| OSSL_STORE_register_loader() register the given B<store_loader> and thereby |
| makes it available for use with OSSL_STORE_open(), OSSL_STORE_load(), |
| OSSL_STORE_eof() and OSSL_STORE_close(). |
| |
| OSSL_STORE_unregister_loader() unregister the store loader for the given |
| B<scheme>. |
| |
| =head1 NOTES |
| |
| The B<file:> scheme has built in support. |
| |
| =head1 RETURN VALUES |
| |
| The functions with the types B<OSSL_STORE_open_fn>, B<OSSL_STORE_ctrl_fn>, |
| B<OSSL_STORE_expect_fn>, |
| B<OSSL_STORE_load_fn>, B<OSSL_STORE_eof_fn> and B<OSSL_STORE_close_fn> have the |
| same return values as OSSL_STORE_open(), 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 B<OSSL_STORE_LOADER> on success, |
| or B<NULL> on failure. |
| |
| OSSL_STORE_LOADER_set_open(), 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 B<NULL> on failure. |
| |
| =head1 SEE ALSO |
| |
| L<ossl_store(7)>, L<OSSL_STORE_open(3)> |
| |
| =head1 HISTORY |
| |
| OSSL_STORE_LOADER(), OSSL_STORE_LOADER_CTX(), OSSL_STORE_LOADER_new(), |
| OSSL_STORE_LOADER_set0_scheme(), 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_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. |
| |
| =head1 COPYRIGHT |
| |
| Copyright 2016-2019 The OpenSSL Project Authors. All Rights Reserved. |
| |
| Licensed under the OpenSSL license (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 |
| L<https://www.openssl.org/source/license.html>. |
| |
| =cut |
