/* ====================================================================

 * Copyright (c) 2001 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).

 *

 */

 /*

 © Portions copyright (c) 2006 Nokia Corporation.  All rights reserved.

 */

#include "cryptlib.h"

#include <openssl/evp.h>

#include <openssl/lhash.h>

#include "eng_int.h"

#if (defined(SYMBIAN) && (defined(__WINSCW__) || defined(__WINS__)))

#include "libcrypto_wsd_macros.h"

#include "libcrypto_wsd.h"

#endif

/* The type of the items in the table */

typedef struct st_engine_pile

	{

	/* The 'nid' of this algorithm/mode */

	int nid;

	/* ENGINEs that implement this algorithm/mode. */

	STACK_OF(ENGINE) *sk;

	/* The default ENGINE to perform this algorithm/mode. */

	ENGINE *funct;

	/* Zero if 'sk' is newer than the cached 'funct', non-zero otherwise */

	int uptodate;

	} ENGINE_PILE;

/* The type exposed in eng_int.h */

struct st_engine_table

	{

	LHASH piles;

	}; /* ENGINE_TABLE */

/* Global flags (ENGINE_TABLE_FLAG_***). */

#ifndef EMULATOR

static unsigned int table_flags = 0;

#else

GET_STATIC_VAR_FROM_TLS(table_flags,eng_table,unsigned int)

#define table_flags (*GET_WSD_VAR_NAME(table_flags,eng_table, s)())

#endif

/* API function manipulating 'table_flags' */

EXPORT_C unsigned int ENGINE_get_table_flags(void)

	{

	return table_flags;

	}

EXPORT_C void ENGINE_set_table_flags(unsigned int flags)

	{

	table_flags = flags;

	}

/* Internal functions for the "piles" hash table */

static unsigned long engine_pile_hash(const ENGINE_PILE *c)

	{

	return c->nid;

	}

static int engine_pile_cmp(const ENGINE_PILE *a, const ENGINE_PILE *b)

	{

	return a->nid - b->nid;

	}

static IMPLEMENT_LHASH_HASH_FN(engine_pile_hash, const ENGINE_PILE *)

static IMPLEMENT_LHASH_COMP_FN(engine_pile_cmp, const ENGINE_PILE *)

static int int_table_check(ENGINE_TABLE **t, int create)

	{

	LHASH *lh;

	if(*t) return 1;

	if(!create) return 0;

	if((lh = lh_new(LHASH_HASH_FN(engine_pile_hash),

			LHASH_COMP_FN(engine_pile_cmp))) == NULL)

		return 0;

	*t = (ENGINE_TABLE *)lh;

	return 1;

	}

/* Privately exposed (via eng_int.h) functions for adding and/or removing

 * ENGINEs from the implementation table */

EXPORT_C int engine_table_register(ENGINE_TABLE **table, ENGINE_CLEANUP_CB *cleanup,

		ENGINE *e, const int *nids, int num_nids, int setdefault)

	{

	int ret = 0, added = 0;

	ENGINE_PILE tmplate, *fnd;

	CRYPTO_w_lock(CRYPTO_LOCK_ENGINE);

	if(!(*table))

		added = 1;

	if(!int_table_check(table, 1))

		goto end;

	if(added)

		/* The cleanup callback needs to be added */

		engine_cleanup_add_first(cleanup);

	while(num_nids--)

		{

		tmplate.nid = *nids;

		fnd = lh_retrieve(&(*table)->piles, &tmplate);

		if(!fnd)

			{

			fnd = OPENSSL_malloc(sizeof(ENGINE_PILE));

			if(!fnd) goto end;

			fnd->uptodate = 0;

			fnd->nid = *nids;

			fnd->sk = sk_ENGINE_new_null();

			if(!fnd->sk)

				{

				OPENSSL_free(fnd);

				goto end;

				}

			fnd->funct = NULL;

			lh_insert(&(*table)->piles, fnd);

			}

		/* A registration shouldn't add duplciate entries */

		(void)sk_ENGINE_delete_ptr(fnd->sk, e);

		/* if 'setdefault', this ENGINE goes to the head of the list */

		if(!sk_ENGINE_push(fnd->sk, e))

			goto end;

		/* "touch" this ENGINE_PILE */

		fnd->uptodate = 1;

		if(setdefault)

			{

			if(!engine_unlocked_init(e))

				{

				ENGINEerr(ENGINE_F_ENGINE_TABLE_REGISTER,

						ENGINE_R_INIT_FAILED);

				goto end;

				}

			if(fnd->funct)

				engine_unlocked_finish(fnd->funct, 0);

			fnd->funct = e;

			}

		nids++;

		}

	ret = 1;

end:

	CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);

	return ret;

	}

static void int_unregister_cb(ENGINE_PILE *pile, ENGINE *e)

	{

	int n;

	/* Iterate the 'c->sk' stack removing any occurance of 'e' */

	while((n = sk_ENGINE_find(pile->sk, e)) >= 0)

		{

		(void)sk_ENGINE_delete(pile->sk, n);

		/* "touch" this ENGINE_CIPHER */

		pile->uptodate = 1;

		}

	if(pile->funct == e)

		{

		engine_unlocked_finish(e, 0);

		pile->funct = NULL;

		}

	}

static IMPLEMENT_LHASH_DOALL_ARG_FN(int_unregister_cb,ENGINE_PILE *,ENGINE *)

EXPORT_C void engine_table_unregister(ENGINE_TABLE **table, ENGINE *e)

	{

	CRYPTO_w_lock(CRYPTO_LOCK_ENGINE);

	if(int_table_check(table, 0))

		lh_doall_arg(&(*table)->piles,

			LHASH_DOALL_ARG_FN(int_unregister_cb), e);

	CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);

	}

static void int_cleanup_cb(ENGINE_PILE *p)

	{

	sk_ENGINE_free(p->sk);

	if(p->funct)

		engine_unlocked_finish(p->funct, 0);

	OPENSSL_free(p);

	}

static IMPLEMENT_LHASH_DOALL_FN(int_cleanup_cb,ENGINE_PILE *)

EXPORT_C void engine_table_cleanup(ENGINE_TABLE **table)

	{

	CRYPTO_w_lock(CRYPTO_LOCK_ENGINE);

	if(*table)

		{

		lh_doall(&(*table)->piles, LHASH_DOALL_FN(int_cleanup_cb));

		lh_free(&(*table)->piles);

		*table = NULL;

		}

	CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);

	}

/* return a functional reference for a given 'nid' */

#ifndef ENGINE_TABLE_DEBUG

EXPORT_C ENGINE *engine_table_select(ENGINE_TABLE **table, int nid)

#else

EXPORT_C ENGINE *engine_table_select_tmp(ENGINE_TABLE **table, int nid, const char *f, int l)

#endif

	{

	ENGINE *ret = NULL;

	ENGINE_PILE tmplate, *fnd=NULL;

	int initres, loop = 0;

	if(!(*table))

		{

#ifdef ENGINE_TABLE_DEBUG

		fprintf(stderr, "engine_table_dbg: %s:%d, nid=%d, nothing "

			"registered!\n", f, l, nid);

#endif

		return NULL;

		}

	CRYPTO_w_lock(CRYPTO_LOCK_ENGINE);

	/* Check again inside the lock otherwise we could race against cleanup

	 * operations. But don't worry about a fprintf(stderr). */

	if(!int_table_check(table, 0)) goto end;

	tmplate.nid = nid;

	fnd = lh_retrieve(&(*table)->piles, &tmplate);

	if(!fnd) goto end;

	if(fnd->funct && engine_unlocked_init(fnd->funct))

		{

#ifdef ENGINE_TABLE_DEBUG

		fprintf(stderr, "engine_table_dbg: %s:%d, nid=%d, using "

			"ENGINE '%s' cached\n", f, l, nid, fnd->funct->id);

#endif

		ret = fnd->funct;

		goto end;

		}

	if(fnd->uptodate)

		{

		ret = fnd->funct;

		goto end;

		}

trynext:

	ret = sk_ENGINE_value(fnd->sk, loop++);

	if(!ret)

		{

#ifdef ENGINE_TABLE_DEBUG

		fprintf(stderr, "engine_table_dbg: %s:%d, nid=%d, no "

				"registered implementations would initialise\n",

				f, l, nid);

#endif

		goto end;

		}

	/* Try to initialise the ENGINE? */

	if((ret->funct_ref > 0) || !(table_flags & ENGINE_TABLE_FLAG_NOINIT))

		initres = engine_unlocked_init(ret);

	else

		initres = 0;

	if(initres)

		{

		/* Update 'funct' */

		if((fnd->funct != ret) && engine_unlocked_init(ret))

			{

			/* If there was a previous default we release it. */

			if(fnd->funct)

				engine_unlocked_finish(fnd->funct, 0);

			fnd->funct = ret;

#ifdef ENGINE_TABLE_DEBUG

			fprintf(stderr, "engine_table_dbg: %s:%d, nid=%d, "

				"setting default to '%s'\n", f, l, nid, ret->id);

#endif

			}

#ifdef ENGINE_TABLE_DEBUG

		fprintf(stderr, "engine_table_dbg: %s:%d, nid=%d, using "

				"newly initialised '%s'\n", f, l, nid, ret->id);

#endif

		goto end;

		}

	goto trynext;

end:

	/* If it failed, it is unlikely to succeed again until some future

	 * registrations have taken place. In all cases, we cache. */

	if(fnd) fnd->uptodate = 1;

#ifdef ENGINE_TABLE_DEBUG

	if(ret)

		fprintf(stderr, "engine_table_dbg: %s:%d, nid=%d, caching "

				"ENGINE '%s'\n", f, l, nid, ret->id);

	else

		fprintf(stderr, "engine_table_dbg: %s:%d, nid=%d, caching "

				"'no matching ENGINE'\n", f, l, nid);

#endif

	CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);

	/* Whatever happened, any failed init()s are not failures in this

	 * context, so clear our error state. */

	ERR_clear_error();

	return ret;

	}