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.. .nr rF 0 . if \nF \{\ . de IX . tm Index:\\$1\t\\n%\t"\\$2" .. . if !\nF==2 \{\ . nr % 0 . nr F 2 . \} . \} .\} .rr rF Fear. Run. Save yourself. No user-serviceable parts.
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Title "OSSL_PROVIDER 3ossl"
way too many mistakes in technical documents.
Some of these functions operate within a library context, please see \s-1OSSL_LIB_CTX\s0\|(3) for further details.
\fBOSSL_PROVIDER_add_builtin() is used to add a built in provider to \fB\s-1OSSL_PROVIDER\s0 store in the given library context, by associating a provider name with a provider initialization function. This name can then be used with OSSL_PROVIDER_load().
\fBOSSL_PROVIDER_load() loads and initializes a provider. This may simply initialize a provider that was previously added with \fBOSSL_PROVIDER_add_builtin() and run its given initialization function, or load a provider module with the given name and run its provider entry point, \*(C`OSSL_provider_init\*(C'. The name can be a path to a provider module, in that case the provider name as returned by OSSL_PROVIDER_get0_name() will be the path. Interpretation of relative paths is platform dependent and they are relative to the configured \*(L"\s-1MODULESDIR\*(R"\s0 directory or the path set in the environment variable \s-1OPENSSL_MODULES\s0 if set.
\fBOSSL_PROVIDER_try_load() functions like OSSL_PROVIDER_load(), except that it does not disable the fallback providers if the provider cannot be loaded and initialized or if retain_fallbacks is nonzero. If the provider loads successfully and retain_fallbacks is zero, the fallback providers are disabled.
\fBOSSL_PROVIDER_unload() unloads the given provider. For a provider added with OSSL_PROVIDER_add_builtin(), this simply runs its teardown function.
\fBOSSL_PROVIDER_available() checks if a named provider is available for use.
\fBOSSL_PROVIDER_do_all() iterates over all loaded providers, calling \fIcb for each one, with the current provider in provider and the \fIcbdata that comes from the caller. If no other provider has been loaded before calling this function, the default provider is still available as fallback. See OSSL_PROVIDER-default\|(7) for more information on this fallback behaviour.
\fBOSSL_PROVIDER_gettable_params() is used to get a provider parameter descriptor set as a constant \s-1OSSL_PARAM\s0\|(3) array.
\fBOSSL_PROVIDER_get_params() is used to get provider parameter values. The caller must prepare the \s-1OSSL_PARAM\s0\|(3) array before calling this function, and the variables acting as buffers for this parameter array should be filled with data when it returns successfully.
\fBOSSL_PROVIDER_self_test() is used to run a provider's self tests on demand. If the self tests fail then the provider will fail to provide any further services and algorithms. OSSL_SELF_TEST_set_callback\|(3) may be called beforehand in order to display diagnostics for the running self tests.
\fBOSSL_PROVIDER_query_operation() calls the provider's query_operation function (see provider\|(7)), if the provider has one. It returns an array of \s-1OSSL_ALGORITHM\s0 for the given operation_id terminated by an all \s-1NULL OSSL_ALGORITHM\s0 entry. This is considered a low-level function that most applications should not need to call.
\fBOSSL_PROVIDER_unquery_operation() calls the provider's unquery_operation function (see provider\|(7)), if the provider has one. This is considered a low-level function that most applications should not need to call.
\fBOSSL_PROVIDER_get0_provider_ctx() returns the provider context for the given provider. The provider context is an opaque handle set by the provider itself and is passed back to the provider by libcrypto in various function calls.
\fBOSSL_PROVIDER_get0_dispatch() returns the provider's dispatch table as it was returned in the out parameter from the provider's init function. See \fBprovider-base\|(7).
If it is permissible to cache references to this array then *no_store is set to 0 or 1 otherwise. If the array is not cacheable then it is assumed to have a short lifetime.
\fBOSSL_PROVIDER_get0_name() returns the name of the given provider.
\fBOSSL_PROVIDER_get_capabilities() provides information about the capabilities supported by the provider specified in prov with the capability name \fIcapability. For each capability of that name supported by the provider it will call the callback cb and supply a set of \s-1OSSL_PARAM\s0\|(3)s describing the capability. It will also pass back the argument arg. For more details about capabilities and what they can be used for please see \*(L"\s-1CAPABILTIIES\*(R"\s0 in provider-base\|(7).
\fBOSSL_PROVIDER_load() and OSSL_PROVIDER_try_load() return a pointer to a provider object on success, or \s-1NULL\s0 on error.
\fBOSSL_PROVIDER_do_all() returns 1 if the callback cb returns 1 for every provider it is called with, or 0 if any provider callback invocation returns 0; callback processing stops at the first callback invocation on a provider that returns 0.
\fBOSSL_PROVIDER_available() returns 1 if the named provider is available, otherwise 0.
\fBOSSL_PROVIDER_gettable_params() returns a pointer to an array of constant \s-1OSSL_PARAM\s0\|(3), or \s-1NULL\s0 if none is provided.
\fBOSSL_PROVIDER_get_params() and returns 1 on success, or 0 on error.
\fBOSSL_PROVIDER_query_operation() returns an array of \s-1OSSL_ALGORITHM\s0 or \s-1NULL\s0 on error.
\fBOSSL_PROVIDER_self_test() returns 1 if the self tests pass, or 0 on error.
.Vb 3 #include <openssl/params.h> #include <openssl/provider.h> #include <openssl/err.h> \& OSSL_PROVIDER *prov = NULL; const char *build = NULL; OSSL_PARAM request[] = { { "buildinfo", OSSL_PARAM_UTF8_PTR, &build, 0, 0 }, { NULL, 0, NULL, 0, 0 } }; \& if ((prov = OSSL_PROVIDER_load(NULL, "foo")) != NULL && OSSL_PROVIDER_get_params(prov, request)) printf("Provider \*(Aqfoo\*(Aq buildinfo: %s\en", build); else ERR_print_errors_fp(stderr); .Ve
Licensed under the Apache License 2.0 (the \*(L"License\*(R"). You may not use this file except in compliance with the License. You can obtain a copy in the file \s-1LICENSE\s0 in the source distribution or at <https://www.openssl.org/source/license.html>.