/* crypto/engine/eng_lib.c */
/*
 * Written by Geoff Thorpe (geoff@geoffthorpe.net) for the OpenSSL project
 * 2000.
 */
/* ====================================================================
 * Copyright (c) 1999-2018 The OpenSSL Project.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 *
 * 3. All advertising materials mentioning features or use of this
 *    software must display the following acknowledgment:
 *    "This product includes software developed by the OpenSSL Project
 *    for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
 *
 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
 *    endorse or promote products derived from this software without
 *    prior written permission. For written permission, please contact
 *    licensing@OpenSSL.org.
 *
 * 5. Products derived from this software may not be called "OpenSSL"
 *    nor may "OpenSSL" appear in their names without prior written
 *    permission of the OpenSSL Project.
 *
 * 6. Redistributions of any form whatsoever must retain the following
 *    acknowledgment:
 *    "This product includes software developed by the OpenSSL Project
 *    for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
 *
 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
 * OF THE POSSIBILITY OF SUCH DAMAGE.
 * ====================================================================
 *
 * This product includes cryptographic software written by Eric Young
 * (eay@cryptsoft.com).  This product includes software written by Tim
 * Hudson (tjh@cryptsoft.com).
 *
 */

#include "eng_int.h"
#include <openssl/rand.h>

/* The "new"/"free" stuff first */

ENGINE *ENGINE_new(void)
{
    ENGINE *ret;

    ret = (ENGINE *)OPENSSL_malloc(sizeof(ENGINE));
    if (ret == NULL) {
        ENGINEerr(ENGINE_F_ENGINE_NEW, ERR_R_MALLOC_FAILURE);
        return NULL;
    }
    memset(ret, 0, sizeof(ENGINE));
    ret->struct_ref = 1;
    engine_ref_debug(ret, 0, 1)
        CRYPTO_new_ex_data(CRYPTO_EX_INDEX_ENGINE, ret, &ret->ex_data);
    return ret;
}

/*
 * Placed here (close proximity to ENGINE_new) so that modifications to the
 * elements of the ENGINE structure are more likely to be caught and changed
 * here.
 */
void engine_set_all_null(ENGINE *e)
{
    e->id = NULL;
    e->name = NULL;
    e->rsa_meth = NULL;
    e->dsa_meth = NULL;
    e->dh_meth = NULL;
    e->rand_meth = NULL;
    e->store_meth = NULL;
    e->ciphers = NULL;
    e->digests = NULL;
    e->destroy = NULL;
    e->init = NULL;
    e->finish = NULL;
    e->ctrl = NULL;
    e->load_privkey = NULL;
    e->load_pubkey = NULL;
    e->cmd_defns = NULL;
    e->flags = 0;
}

int engine_free_util(ENGINE *e, int locked)
{
    int i;

    if (e == NULL) {
        ENGINEerr(ENGINE_F_ENGINE_FREE_UTIL, ERR_R_PASSED_NULL_PARAMETER);
        return 0;
    }
    if (locked)
        i = CRYPTO_add(&e->struct_ref, -1, CRYPTO_LOCK_ENGINE);
    else
        i = --e->struct_ref;
    engine_ref_debug(e, 0, -1)
        if (i > 0)
        return 1;
#ifdef REF_CHECK
    if (i < 0) {
        fprintf(stderr, "ENGINE_free, bad structural reference count\n");
        abort();
    }
#endif
    /* Free up any dynamically allocated public key methods */
    engine_pkey_meths_free(e);
    engine_pkey_asn1_meths_free(e);
    /*
     * Give the ENGINE a chance to do any structural cleanup corresponding to
     * allocation it did in its constructor (eg. unload error strings)
     */
    if (e->destroy)
        e->destroy(e);
    CRYPTO_free_ex_data(CRYPTO_EX_INDEX_ENGINE, e, &e->ex_data);
    OPENSSL_free(e);
    return 1;
}

int ENGINE_free(ENGINE *e)
{
    return engine_free_util(e, 1);
}

/* Cleanup stuff */

/*
 * ENGINE_cleanup() is coded such that anything that does work that will need
 * cleanup can register a "cleanup" callback here. That way we don't get
 * linker bloat by referring to all *possible* cleanups, but any linker bloat
 * into code "X" will cause X's cleanup function to end up here.
 */
static STACK_OF(ENGINE_CLEANUP_ITEM) *cleanup_stack = NULL;
static int int_cleanup_check(int create)
{
    if (cleanup_stack)
        return 1;
    if (!create)
        return 0;
    cleanup_stack = sk_ENGINE_CLEANUP_ITEM_new_null();
    return (cleanup_stack ? 1 : 0);
}

static ENGINE_CLEANUP_ITEM *int_cleanup_item(ENGINE_CLEANUP_CB *cb)
{
    ENGINE_CLEANUP_ITEM *item = OPENSSL_malloc(sizeof(ENGINE_CLEANUP_ITEM));
    if (!item)
        return NULL;
    item->cb = cb;
    return item;
}

void engine_cleanup_add_first(ENGINE_CLEANUP_CB *cb)
{
    ENGINE_CLEANUP_ITEM *item;
    if (!int_cleanup_check(1))
        return;
    item = int_cleanup_item(cb);
    if (item)
        sk_ENGINE_CLEANUP_ITEM_insert(cleanup_stack, item, 0);
}

void engine_cleanup_add_last(ENGINE_CLEANUP_CB *cb)
{
    ENGINE_CLEANUP_ITEM *item;
    if (!int_cleanup_check(1))
        return;
    item = int_cleanup_item(cb);
    if (item != NULL) {
        if (sk_ENGINE_CLEANUP_ITEM_push(cleanup_stack, item) <= 0)
            OPENSSL_free(item);
    }
}

/* The API function that performs all cleanup */
static void engine_cleanup_cb_free(ENGINE_CLEANUP_ITEM *item)
{
    (*(item->cb)) ();
    OPENSSL_free(item);
}

void ENGINE_cleanup(void)
{
    if (int_cleanup_check(0)) {
        sk_ENGINE_CLEANUP_ITEM_pop_free(cleanup_stack,
                                        engine_cleanup_cb_free);
        cleanup_stack = NULL;
    }
    /*
     * FIXME: This should be handled (somehow) through RAND, eg. by it
     * registering a cleanup callback.
     */
    RAND_set_rand_method(NULL);
}

/* Now the "ex_data" support */

int ENGINE_get_ex_new_index(long argl, void *argp, CRYPTO_EX_new *new_func,
                            CRYPTO_EX_dup *dup_func,
                            CRYPTO_EX_free *free_func)
{
    return CRYPTO_get_ex_new_index(CRYPTO_EX_INDEX_ENGINE, argl, argp,
                                   new_func, dup_func, free_func);
}

int ENGINE_set_ex_data(ENGINE *e, int idx, void *arg)
{
    return (CRYPTO_set_ex_data(&e->ex_data, idx, arg));
}

void *ENGINE_get_ex_data(const ENGINE *e, int idx)
{
    return (CRYPTO_get_ex_data(&e->ex_data, idx));
}

/*
 * Functions to get/set an ENGINE's elements - mainly to avoid exposing the
 * ENGINE structure itself.
 */

int ENGINE_set_id(ENGINE *e, const char *id)
{
    if (id == NULL) {
        ENGINEerr(ENGINE_F_ENGINE_SET_ID, ERR_R_PASSED_NULL_PARAMETER);
        return 0;
    }
    e->id = id;
    return 1;
}

int ENGINE_set_name(ENGINE *e, const char *name)
{
    if (name == NULL) {
        ENGINEerr(ENGINE_F_ENGINE_SET_NAME, ERR_R_PASSED_NULL_PARAMETER);
        return 0;
    }
    e->name = name;
    return 1;
}

int ENGINE_set_destroy_function(ENGINE *e, ENGINE_GEN_INT_FUNC_PTR destroy_f)
{
    e->destroy = destroy_f;
    return 1;
}

int ENGINE_set_init_function(ENGINE *e, ENGINE_GEN_INT_FUNC_PTR init_f)
{
    e->init = init_f;
    return 1;
}

int ENGINE_set_finish_function(ENGINE *e, ENGINE_GEN_INT_FUNC_PTR finish_f)
{
    e->finish = finish_f;
    return 1;
}

int ENGINE_set_ctrl_function(ENGINE *e, ENGINE_CTRL_FUNC_PTR ctrl_f)
{
    e->ctrl = ctrl_f;
    return 1;
}

int ENGINE_set_flags(ENGINE *e, int flags)
{
    e->flags = flags;
    return 1;
}

int ENGINE_set_cmd_defns(ENGINE *e, const ENGINE_CMD_DEFN *defns)
{
    e->cmd_defns = defns;
    return 1;
}

const char *ENGINE_get_id(const ENGINE *e)
{
    return e->id;
}

const char *ENGINE_get_name(const ENGINE *e)
{
    return e->name;
}

ENGINE_GEN_INT_FUNC_PTR ENGINE_get_destroy_function(const ENGINE *e)
{
    return e->destroy;
}

ENGINE_GEN_INT_FUNC_PTR ENGINE_get_init_function(const ENGINE *e)
{
    return e->init;
}

ENGINE_GEN_INT_FUNC_PTR ENGINE_get_finish_function(const ENGINE *e)
{
    return e->finish;
}

ENGINE_CTRL_FUNC_PTR ENGINE_get_ctrl_function(const ENGINE *e)
{
    return e->ctrl;
}

int ENGINE_get_flags(const ENGINE *e)
{
    return e->flags;
}

const ENGINE_CMD_DEFN *ENGINE_get_cmd_defns(const ENGINE *e)
{
    return e->cmd_defns;
}

/*
 * eng_lib.o is pretty much linked into anything that touches ENGINE already,
 * so put the "static_state" hack here.
 */

static int internal_static_hack = 0;

void *ENGINE_get_static_state(void)
{
    return &internal_static_hack;
}
