OSSL_DECODER, OSSL_DECODER_fetch, OSSL_DECODER_up_ref, OSSL_DECODER_free,
OSSL_DECODER_get0_provider, OSSL_DECODER_get0_properties, OSSL_DECODER_is_a,
OSSL_DECODER_get0_name, OSSL_DECODER_get0_description,
OSSL_DECODER_do_all_provided, OSSL_DECODER_names_do_all,
OSSL_DECODER_gettable_params, OSSL_DECODER_get_params - Decoder method
routines
#include <openssl/decoder.h>
typedef struct ossl_decoder_st OSSL_DECODER;
OSSL_DECODER *OSSL_DECODER_fetch(OSSL_LIB_CTX *ctx, const char *name,
const char *properties);
int OSSL_DECODER_up_ref(OSSL_DECODER *decoder);
void OSSL_DECODER_free(OSSL_DECODER *decoder);
const OSSL_PROVIDER *OSSL_DECODER_get0_provider(const OSSL_DECODER *decoder);
const char *OSSL_DECODER_get0_properties(const OSSL_DECODER *decoder);
int OSSL_DECODER_is_a(const OSSL_DECODER *decoder, const char *name);
const char *OSSL_DECODER_get0_name(const OSSL_DECODER *decoder);
const char *OSSL_DECODER_get0_description(const OSSL_DECODER *decoder);
void OSSL_DECODER_do_all_provided(OSSL_LIB_CTX *libctx,
void (*fn)(OSSL_DECODER *decoder, void *arg),
void *arg);
int OSSL_DECODER_names_do_all(const OSSL_DECODER *decoder,
void (*fn)(const char *name, void *data),
void *data);
const OSSL_PARAM *OSSL_DECODER_gettable_params(OSSL_DECODER *decoder);
int OSSL_DECODER_get_params(OSSL_DECODER_CTX *ctx, const OSSL_PARAM params[]);
OSSL_DECODER is a method for decoders, which know how to decode encoded
data into an object of some type that the rest of OpenSSL knows how to handle.
OSSL_DECODER_fetch() looks for an algorithm within the provider that has
been loaded into the
OSSL_LIB_CTX given by
ctx, having the name
given by
name and the properties given by
properties. The
name determines what type of object the fetched decoder method is
expected to be able to decode, and the properties are used to determine the
expected output type. For known properties and the values they may have,
please have a look in "Names and properties" in
provider-encoder(7).
OSSL_DECODER_up_ref() increments the reference count for the given
decoder.
OSSL_DECODER_free() decrements the reference count for the given
decoder, and when the count reaches zero, frees it.
OSSL_DECODER_get0_provider() returns the provider of the given
decoder.
OSSL_DECODER_get0_properties() returns the property definition associated
with the given
decoder.
OSSL_DECODER_is_a() checks if
decoder is an implementation of an
algorithm that's identifiable with
name.
OSSL_DECODER_get0_name() returns the name used to fetch the given
decoder.
OSSL_DECODER_get0_description() returns a description of the
decoder, meant for display and human consumption. The description is at
the discretion of the
decoder implementation.
OSSL_DECODER_names_do_all() traverses all names for the given
decoder, and calls
fn with each name and
data as
arguments.
OSSL_DECODER_do_all_provided() traverses all decoder implementations by
all activated providers in the library context
libctx, and for each of
the implementations, calls
fn with the implementation method and
arg as arguments.
OSSL_DECODER_gettable_params() returns an
OSSL_PARAM(3) array of
parameter descriptors.
OSSL_DECODER_get_params() attempts to get parameters specified with an
OSSL_PARAM(3) array
params. Parameters that the implementation
doesn't recognise should be ignored.
OSSL_DECODER_fetch() returns a pointer to an OSSL_DECODER object, or NULL
on error.
OSSL_DECODER_up_ref() returns 1 on success, or 0 on error.
OSSL_DECODER_free() doesn't return any value.
OSSL_DECODER_get0_provider() returns a pointer to a provider object, or
NULL on error.
OSSL_DECODER_get0_properties() returns a pointer to a property definition
string, or NULL on error.
OSSL_DECODER_is_a() returns 1 if
decoder was identifiable,
otherwise 0.
OSSL_DECODER_get0_name() returns the algorithm name from the provided
implementation for the given
decoder. Note that the
decoder may
have multiple synonyms associated with it. In this case the first name from
the algorithm definition is returned. Ownership of the returned string is
retained by the
decoder object and should not be freed by the caller.
OSSL_DECODER_get0_description() returns a pointer to a description, or
NULL if there isn't one.
OSSL_DECODER_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_DECODER_fetch() may be called implicitly by other fetching
functions, using the same library context and properties. Any other API that
uses keys will typically do this.
To list all decoders in a provider to a bio_out:
static void collect_decoders(OSSL_DECODER *decoder, void *stack)
{
STACK_OF(OSSL_DECODER) *decoder_stack = stack;
sk_OSSL_DECODER_push(decoder_stack, decoder);
OSSL_DECODER_up_ref(decoder);
}
void print_name(const char *name, void *vdata)
{
BIO *bio = vdata;
BIO_printf(bio, "%s ", name);
}
STACK_OF(OSSL_DECODER) *decoders;
int i;
decoders = sk_OSSL_DECODER_new_null();
BIO_printf(bio_out, "DECODERs provided by %s:\n", provider);
OSSL_DECODER_do_all_provided(NULL, collect_decoders,
decoders);
for (i = 0; i < sk_OSSL_DECODER_num(decoders); i++) {
OSSL_DECODER *decoder = sk_OSSL_DECODER_value(decoders, i);
if (strcmp(OSSL_PROVIDER_get0_name(OSSL_DECODER_get0_provider(decoder)),
provider) != 0)
continue;
if (OSSL_DECODER_names_do_all(decoder, print_name, bio_out))
BIO_printf(bio_out, "\n");
}
sk_OSSL_DECODER_pop_free(decoders, OSSL_DECODER_free);
provider(7),
OSSL_DECODER_CTX(3),
OSSL_DECODER_from_bio(3),
OSSL_DECODER_CTX_new_for_pkey(3),
OSSL_LIB_CTX(3)
The functions described here were added in OpenSSL 3.0.
Copyright 2020-2023 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>.