b0edda11cb
Reviewed-by: Richard Levitte <levitte@openssl.org> (Merged from https://github.com/openssl/openssl/pull/5689)
152 lines
5.7 KiB
Text
152 lines
5.7 KiB
Text
=pod
|
|
|
|
=head1 NAME
|
|
|
|
OSSL_STORE_CTX, OSSL_STORE_post_process_info_fn, OSSL_STORE_open,
|
|
OSSL_STORE_ctrl, OSSL_STORE_load, OSSL_STORE_eof, OSSL_STORE_error,
|
|
OSSL_STORE_close - Types and functions to read objects from a URI
|
|
|
|
=head1 SYNOPSIS
|
|
|
|
#include <openssl/store.h>
|
|
|
|
typedef struct ossl_store_ctx_st OSSL_STORE_CTX;
|
|
|
|
typedef OSSL_STORE_INFO *(*OSSL_STORE_post_process_info_fn)(OSSL_STORE_INFO *,
|
|
void *);
|
|
|
|
OSSL_STORE_CTX *OSSL_STORE_open(const char *uri, const UI_METHOD *ui_method,
|
|
void *ui_data,
|
|
OSSL_STORE_post_process_info_fn post_process,
|
|
void *post_process_data);
|
|
int OSSL_STORE_ctrl(OSSL_STORE_CTX *ctx, int cmd, ... /* args */);
|
|
OSSL_STORE_INFO *OSSL_STORE_load(OSSL_STORE_CTX *ctx);
|
|
int OSSL_STORE_eof(OSSL_STORE_CTX *ctx);
|
|
int OSSL_STORE_error(OSSL_STORE_CTX *ctx);
|
|
int OSSL_STORE_close(OSSL_STORE_CTX *ctx);
|
|
|
|
=head1 DESCRIPTION
|
|
|
|
These functions help the application to fetch supported objects (see
|
|
L<OSSL_STORE_INFO(3)/SUPPORTED OBJECTS> for information on which those are)
|
|
from a given URI (see L</SUPPORTED SCHEMES> for more information on
|
|
the supported URI schemes).
|
|
The general method to do so is to "open" the URI using OSSL_STORE_open(),
|
|
read each available and supported object using OSSL_STORE_load() as long as
|
|
OSSL_STORE_eof() hasn't been reached, and finish it off with OSSL_STORE_close().
|
|
|
|
The retrieved information is stored in a B<OSSL_STORE_INFO>, which is further
|
|
described in L<OSSL_STORE_INFO(3)>.
|
|
|
|
=head2 Types
|
|
|
|
B<OSSL_STORE_CTX> is a context variable that holds all the internal
|
|
information for OSSL_STORE_open(), OSSL_STORE_load(), OSSL_STORE_eof() and
|
|
OSSL_STORE_close() to work together.
|
|
|
|
=head2 Functions
|
|
|
|
OSSL_STORE_open() takes a uri or path B<uri>, password UI method
|
|
B<ui_method> with associated data B<ui_data>, and post processing
|
|
callback B<post_process> with associated data B<post_process_data>,
|
|
opens a channel to the data located at that URI and returns a
|
|
B<OSSL_STORE_CTX> with all necessary internal information.
|
|
The given B<ui_method> and B<ui_data_data> will be reused by all
|
|
functions that use B<OSSL_STORE_CTX> when interaction is needed.
|
|
The given B<post_process> and B<post_process_data> will be reused by
|
|
OSSL_STORE_load() to manipulate or drop the value to be returned.
|
|
The B<post_process> function drops values by returning B<NULL>, which
|
|
will cause OSSL_STORE_load() to start its process over with loading
|
|
the next object, until B<post_process> returns something other than
|
|
B<NULL>, or the end of data is reached as indicated by OSSL_STORE_eof().
|
|
|
|
OSSL_STORE_ctrl() takes a B<OSSL_STORE_CTX>, and command number B<cmd> and
|
|
more arguments not specified here.
|
|
The available loader specific command numbers and arguments they each
|
|
take depends on the loader that's used and is documented together with
|
|
that loader.
|
|
|
|
There are also global controls available:
|
|
|
|
=over 4
|
|
|
|
=item B<OSSL_STORE_C_USE_SECMEM>
|
|
|
|
Controls if the loader should attempt to use secure memory for any
|
|
allocated B<OSSL_STORE_INFO> and its contents.
|
|
This control expects one argument, a pointer to an B<int> that is expected to
|
|
have the value 1 (yes) or 0 (no).
|
|
Any other value is an error.
|
|
|
|
=back
|
|
|
|
OSSL_STORE_load() takes a B<OSSL_STORE_CTX>, tries to load the next available
|
|
object and return it wrapped with B<OSSL_STORE_INFO>.
|
|
|
|
OSSL_STORE_eof() takes a B<OSSL_STORE_CTX> and checks if we've reached the end
|
|
of data.
|
|
|
|
OSSL_STORE_error() takes a B<OSSL_STORE_CTX> and checks if an error occurred in
|
|
the last OSSL_STORE_load() call.
|
|
Note that it may still be meaningful to try and load more objects, unless
|
|
OSSL_STORE_eof() shows that the end of data has been reached.
|
|
|
|
OSSL_STORE_close() takes a B<OSSL_STORE_CTX>, closes the channel that was opened
|
|
by OSSL_STORE_open() and frees all other information that was stored in the
|
|
B<OSSL_STORE_CTX>, as well as the B<OSSL_STORE_CTX> itself.
|
|
|
|
=head1 SUPPORTED SCHEMES
|
|
|
|
The basic supported scheme is B<file:>.
|
|
Any other scheme can be added dynamically, using
|
|
OSSL_STORE_register_loader().
|
|
|
|
=head1 NOTES
|
|
|
|
A string without a scheme prefix (that is, a non-URI string) is
|
|
implicitly interpreted as using the F<file:> scheme.
|
|
|
|
There are some tools that can be used together with
|
|
OSSL_STORE_open() to determine if any failure is caused by an unparsable
|
|
URI, or if it's a different error (such as memory allocation
|
|
failures); if the URI was parsable but the scheme unregistered, the
|
|
top error will have the reason C<OSSL_STORE_R_UNREGISTERED_SCHEME>.
|
|
|
|
=head1 RETURN VALUES
|
|
|
|
OSSL_STORE_open() returns a pointer to a B<OSSL_STORE_CTX> on success, or
|
|
B<NULL> on failure.
|
|
|
|
OSSL_STORE_load() returns a pointer to a B<OSSL_STORE_INFO> on success, or
|
|
B<NULL> on error or when end of data is reached.
|
|
Use OSSL_STORE_error() and OSSL_STORE_eof() to determine the meaning of a
|
|
returned B<NULL>.
|
|
|
|
OSSL_STORE_eof() returns 1 if the end of data has been reached, otherwise
|
|
0.
|
|
|
|
OSSL_STORE_error() returns 1 if an error occurred in an OSSL_STORE_load() call,
|
|
otherwise 0.
|
|
|
|
OSSL_STORE_ctrl() and OSSL_STORE_close() returns 1 on success, or 0 on failure.
|
|
|
|
=head1 SEE ALSO
|
|
|
|
L<ossl_store(7)>, L<OSSL_STORE_INFO(3)>, L<OSSL_STORE_register_loader(3)>
|
|
|
|
=head1 HISTORY
|
|
|
|
OSSL_STORE_CTX(), OSSL_STORE_post_process_info_fn(), OSSL_STORE_open(),
|
|
OSSL_STORE_ctrl(), OSSL_STORE_load(), OSSL_STORE_eof() and OSSL_STORE_close()
|
|
were added to OpenSSL 1.1.1.
|
|
|
|
=head1 COPYRIGHT
|
|
|
|
Copyright 2016-2018 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
|