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/* Copyright (c) 2014, Google Inc.
*
* Permission to use, copy, modify, and/or distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
* SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
* OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
* CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. */
#ifndef OPENSSL_HEADER_ENGINE_H
#define OPENSSL_HEADER_ENGINE_H
#include <openssl/base.h>
#if defined(__cplusplus)
extern "C" {
#endif
// Engines are collections of methods. Methods are tables of function pointers,
// defined for certain algorithms, that allow operations on those algorithms to
// be overridden via a callback. This can be used, for example, to implement an
// RSA* that forwards operations to a hardware module.
//
// Methods are reference counted but |ENGINE|s are not. When creating a method,
// you should zero the whole structure and fill in the function pointers that
// you wish before setting it on an |ENGINE|. Any functions pointers that
// are NULL indicate that the default behaviour should be used.
// Allocation and destruction.
// ENGINE_new returns an empty ENGINE that uses the default method for all
// algorithms.
OPENSSL_EXPORT ENGINE *ENGINE_new(void);
// ENGINE_free decrements the reference counts for all methods linked from
// |engine| and frees |engine| itself. It returns one.
OPENSSL_EXPORT int ENGINE_free(ENGINE *engine);
// Method accessors.
//
// Method accessors take a method pointer and the size of the structure. The
// size allows for ABI compatibility in the case that the method structure is
// extended with extra elements at the end. Methods are always copied by the
// set functions.
//
// Set functions return one on success and zero on allocation failure.
OPENSSL_EXPORT int ENGINE_set_RSA_method(ENGINE *engine,
const RSA_METHOD *method,
size_t method_size);
OPENSSL_EXPORT RSA_METHOD *ENGINE_get_RSA_method(const ENGINE *engine);
OPENSSL_EXPORT int ENGINE_set_ECDSA_method(ENGINE *engine,
const ECDSA_METHOD *method,
size_t method_size);
OPENSSL_EXPORT ECDSA_METHOD *ENGINE_get_ECDSA_method(const ENGINE *engine);
// Generic method functions.
//
// These functions take a void* type but actually operate on all method
// structures.
// METHOD_ref increments the reference count of |method|. This is a no-op for
// now because all methods are currently static.
void METHOD_ref(void *method);
// METHOD_unref decrements the reference count of |method| and frees it if the
// reference count drops to zero. This is a no-op for now because all methods
// are currently static.
void METHOD_unref(void *method);
// Private functions.
// openssl_method_common_st contains the common part of all method structures.
// This must be the first member of all method structures.
struct openssl_method_common_st {
int references; // dummy – not used.
char is_static;
};
#if defined(__cplusplus)
} // extern C
extern "C++" {
BSSL_NAMESPACE_BEGIN
BORINGSSL_MAKE_DELETER(ENGINE, ENGINE_free)
BSSL_NAMESPACE_END
} // extern C++
#endif
#define ENGINE_R_OPERATION_NOT_SUPPORTED 100
#endif // OPENSSL_HEADER_ENGINE_H