[thirdparty/openssl.git] / crypto / engine / eng_table.c

/*
 * Copyright 2001-2024 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
 */

#include "internal/cryptlib.h"
#include <openssl/evp.h>
#include <openssl/lhash.h>
#include <openssl/trace.h>
#include "eng_local.h"

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

/* The type exposed in eng_local.h */
struct st_engine_table {
    LHASH_OF(ENGINE_PILE) piles;
};                              /* ENGINE_TABLE */

typedef struct st_engine_pile_doall {
    engine_table_doall_cb *cb;
    void *arg;
} ENGINE_PILE_DOALL;

/* Global flags (ENGINE_TABLE_FLAG_***). */
static unsigned int table_flags = 0;

/* API function manipulating 'table_flags' */
unsigned int ENGINE_get_table_flags(void)
{
    return table_flags;
}

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 int int_table_check(ENGINE_TABLE **t, int create)
{
    LHASH_OF(ENGINE_PILE) *lh;

    if (*t)
        return 1;
    if (!create)
        return 0;
    if ((lh = lh_ENGINE_PILE_new(engine_pile_hash, engine_pile_cmp)) == NULL)
        return 0;
    *t = (ENGINE_TABLE *)lh;
    return 1;
}

/*
 * Privately exposed (via eng_local.h) functions for adding and/or removing
 * ENGINEs from the implementation table
 */
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;

    if (!CRYPTO_THREAD_write_lock(global_engine_lock))
        return 0;
    if (!(*table))
        added = 1;
    if (!int_table_check(table, 1))
        goto end;
    /* The cleanup callback needs to be added */
    if (added && !engine_cleanup_add_first(cleanup)) {
        lh_ENGINE_PILE_free(&(*table)->piles);
        *table = NULL;
        goto end;
    }
    while (num_nids--) {
        tmplate.nid = *nids;
        fnd = lh_ENGINE_PILE_retrieve(&(*table)->piles, &tmplate);
        if (!fnd) {
            fnd = OPENSSL_malloc(sizeof(*fnd));
            if (fnd == NULL)
                goto end;
            fnd->uptodate = 1;
            fnd->nid = *nids;
            fnd->sk = sk_ENGINE_new_null();
            if (!fnd->sk) {
                OPENSSL_free(fnd);
                goto end;
            }
            fnd->funct = NULL;
            (void)lh_ENGINE_PILE_insert(&(*table)->piles, fnd);
            if (lh_ENGINE_PILE_retrieve(&(*table)->piles, &tmplate) != fnd) {
                sk_ENGINE_free(fnd->sk);
                OPENSSL_free(fnd);
                goto end;
            }
        }
        /* A registration shouldn't add duplicate 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 = 0;
        if (setdefault) {
            if (!engine_unlocked_init(e)) {
                ERR_raise(ERR_LIB_ENGINE, ENGINE_R_INIT_FAILED);
                goto end;
            }
            if (fnd->funct)
                engine_unlocked_finish(fnd->funct, 0);
            fnd->funct = e;
            fnd->uptodate = 1;
        }
        nids++;
    }
    ret = 1;
 end:
    CRYPTO_THREAD_unlock(global_engine_lock);
    return ret;
}

static void int_unregister_cb(ENGINE_PILE *pile, ENGINE *e)
{
    int n;
    /* Iterate the 'c->sk' stack removing any occurrence of 'e' */
    while ((n = sk_ENGINE_find(pile->sk, e)) >= 0) {
        (void)sk_ENGINE_delete(pile->sk, n);
        pile->uptodate = 0;
    }
    if (pile->funct == e) {
        engine_unlocked_finish(e, 0);
        pile->funct = NULL;
    }
}

IMPLEMENT_LHASH_DOALL_ARG(ENGINE_PILE, ENGINE);

void engine_table_unregister(ENGINE_TABLE **table, ENGINE *e)
{
    if (!CRYPTO_THREAD_write_lock(global_engine_lock))
        /* Can't return a value. :( */
        return;
    if (int_table_check(table, 0))
        lh_ENGINE_PILE_doall_ENGINE(&(*table)->piles, int_unregister_cb, e);
    CRYPTO_THREAD_unlock(global_engine_lock);
}

static void int_cleanup_cb_doall(ENGINE_PILE *p)
{
    if (p == NULL)
        return;
    sk_ENGINE_free(p->sk);
    if (p->funct)
        engine_unlocked_finish(p->funct, 0);
    OPENSSL_free(p);
}

void engine_table_cleanup(ENGINE_TABLE **table)
{
    if (!CRYPTO_THREAD_write_lock(global_engine_lock))
        return;
    if (*table) {
        lh_ENGINE_PILE_doall(&(*table)->piles, int_cleanup_cb_doall);
        lh_ENGINE_PILE_free(&(*table)->piles);
        *table = NULL;
    }
    CRYPTO_THREAD_unlock(global_engine_lock);
}

/* return a functional reference for a given 'nid' */
ENGINE *ossl_engine_table_select(ENGINE_TABLE **table, int nid,
                                 const char *f, int l)
{
    ENGINE *ret = NULL;
    ENGINE_PILE tmplate, *fnd = NULL;
    int initres, loop = 0;

#ifndef OPENSSL_NO_AUTOLOAD_CONFIG
    /* Load the config before trying to check if engines are available */
    OPENSSL_init_crypto(OPENSSL_INIT_LOAD_CONFIG, NULL);
#endif

    if (!(*table)) {
        OSSL_TRACE3(ENGINE_TABLE,
                   "%s:%d, nid=%d, nothing registered!\n",
                   f, l, nid);
        return NULL;
    }

    if (!CRYPTO_THREAD_write_lock(global_engine_lock))
        return NULL;

    ERR_set_mark();
    /*
     * Check again inside the lock otherwise we could race against cleanup
     * operations. But don't worry about a debug printout
     */
    if (!int_table_check(table, 0))
        goto end;
    tmplate.nid = nid;
    fnd = lh_ENGINE_PILE_retrieve(&(*table)->piles, &tmplate);
    if (!fnd)
        goto end;
    if (fnd->funct && engine_unlocked_init(fnd->funct)) {
        OSSL_TRACE4(ENGINE_TABLE,
                   "%s:%d, nid=%d, using ENGINE '%s' cached\n",
                   f, l, nid, fnd->funct->id);
        ret = fnd->funct;
        goto end;
    }
    if (fnd->uptodate) {
        ret = fnd->funct;
        goto end;
    }
 trynext:
    ret = sk_ENGINE_value(fnd->sk, loop++);
    if (!ret) {
        OSSL_TRACE3(ENGINE_TABLE,
                    "%s:%d, nid=%d, "
                    "no registered implementations would initialise\n",
                    f, l, nid);
        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;
            OSSL_TRACE4(ENGINE_TABLE,
                        "%s:%d, nid=%d, setting default to '%s'\n",
                        f, l, nid, ret->id);
        }
        OSSL_TRACE4(ENGINE_TABLE,
                    "%s:%d, nid=%d, using newly initialised '%s'\n",
                    f, l, nid, ret->id);
        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;
    if (ret)
        OSSL_TRACE4(ENGINE_TABLE,
                   "%s:%d, nid=%d, caching ENGINE '%s'\n",
                   f, l, nid, ret->id);
    else
        OSSL_TRACE3(ENGINE_TABLE,
                    "%s:%d, nid=%d, caching 'no matching ENGINE'\n",
                    f, l, nid);
    CRYPTO_THREAD_unlock(global_engine_lock);
    /*
     * Whatever happened, any failed init()s are not failures in this
     * context, so clear our error state.
     */
    ERR_pop_to_mark();
    return ret;
}

/* Table enumeration */

static void int_dall(const ENGINE_PILE *pile, ENGINE_PILE_DOALL *dall)
{
    dall->cb(pile->nid, pile->sk, pile->funct, dall->arg);
}

IMPLEMENT_LHASH_DOALL_ARG_CONST(ENGINE_PILE, ENGINE_PILE_DOALL);

void engine_table_doall(ENGINE_TABLE *table, engine_table_doall_cb *cb,
                        void *arg)
{
    ENGINE_PILE_DOALL dall;
    dall.cb = cb;
    dall.arg = arg;
    if (table)
        lh_ENGINE_PILE_doall_ENGINE_PILE_DOALL(&table->piles, int_dall, &dall);
}
Commit	Line	Data
	1	/*
	2	* Copyright 2001-2024 The OpenSSL Project Authors. All Rights Reserved.
	3	*
	4	* Licensed under the Apache License 2.0 (the "License"). You may not use
	5	* this file except in compliance with the License. You can obtain a copy
	6	* in the file LICENSE in the source distribution or at
	7	* https://www.openssl.org/source/license.html
	8	*/
	9
	10	#include "internal/cryptlib.h"
	11	#include <openssl/evp.h>
	12	#include <openssl/lhash.h>
	13	#include <openssl/trace.h>
	14	#include "eng_local.h"
	15
	16	/* The type of the items in the table */
	17	struct st_engine_pile {
	18	/* The 'nid' of this algorithm/mode */
	19	int nid;
	20	/* ENGINEs that implement this algorithm/mode. */
	21	STACK_OF(ENGINE) *sk;
	22	/* The default ENGINE to perform this algorithm/mode. */
	23	ENGINE *funct;
	24	/*
	25	* Zero if 'sk' is newer than the cached 'funct', non-zero otherwise
	26	*/
	27	int uptodate;
	28	};
	29
	30	/* The type exposed in eng_local.h */
	31	struct st_engine_table {
	32	LHASH_OF(ENGINE_PILE) piles;
	33	}; /* ENGINE_TABLE */
	34
	35	typedef struct st_engine_pile_doall {
	36	engine_table_doall_cb *cb;
	37	void *arg;
	38	} ENGINE_PILE_DOALL;
	39
	40	/* Global flags (ENGINE_TABLE_FLAG_**). /
	41	static unsigned int table_flags = 0;
	42
	43	/* API function manipulating 'table_flags' */
	44	unsigned int ENGINE_get_table_flags(void)
	45	{
	46	return table_flags;
	47	}
	48
	49	void ENGINE_set_table_flags(unsigned int flags)
	50	{
	51	table_flags = flags;
	52	}
	53
	54	/* Internal functions for the "piles" hash table */
	55	static unsigned long engine_pile_hash(const ENGINE_PILE *c)
	56	{
	57	return c->nid;
	58	}
	59
	60	static int engine_pile_cmp(const ENGINE_PILE a, const ENGINE_PILE b)
	61	{
	62	return a->nid - b->nid;
	63	}
	64
	65	static int int_table_check(ENGINE_TABLE **t, int create)
	66	{
	67	LHASH_OF(ENGINE_PILE) *lh;
	68
	69	if (*t)
	70	return 1;
	71	if (!create)
	72	return 0;
	73	if ((lh = lh_ENGINE_PILE_new(engine_pile_hash, engine_pile_cmp)) == NULL)
	74	return 0;
	75	t = (ENGINE_TABLE )lh;
	76	return 1;
	77	}
	78
	79	/*
	80	* Privately exposed (via eng_local.h) functions for adding and/or removing
	81	* ENGINEs from the implementation table
	82	*/
	83	int engine_table_register(ENGINE_TABLE *table, ENGINE_CLEANUP_CB cleanup,
	84	ENGINE e, const int nids, int num_nids,
	85	int setdefault)
	86	{
	87	int ret = 0, added = 0;
	88	ENGINE_PILE tmplate, *fnd;
	89
	90	if (!CRYPTO_THREAD_write_lock(global_engine_lock))
	91	return 0;
	92	if (!(*table))
	93	added = 1;
	94	if (!int_table_check(table, 1))
	95	goto end;
	96	/* The cleanup callback needs to be added */
	97	if (added && !engine_cleanup_add_first(cleanup)) {
	98	lh_ENGINE_PILE_free(&(*table)->piles);
	99	*table = NULL;
	100	goto end;
	101	}
	102	while (num_nids--) {
	103	tmplate.nid = *nids;
	104	fnd = lh_ENGINE_PILE_retrieve(&(*table)->piles, &tmplate);
	105	if (!fnd) {
	106	fnd = OPENSSL_malloc(sizeof(*fnd));
	107	if (fnd == NULL)
	108	goto end;
	109	fnd->uptodate = 1;
	110	fnd->nid = *nids;
	111	fnd->sk = sk_ENGINE_new_null();
	112	if (!fnd->sk) {
	113	OPENSSL_free(fnd);
	114	goto end;
	115	}
	116	fnd->funct = NULL;
	117	(void)lh_ENGINE_PILE_insert(&(*table)->piles, fnd);
	118	if (lh_ENGINE_PILE_retrieve(&(*table)->piles, &tmplate) != fnd) {
	119	sk_ENGINE_free(fnd->sk);
	120	OPENSSL_free(fnd);
	121	goto end;
	122	}
	123	}
	124	/* A registration shouldn't add duplicate entries */
	125	(void)sk_ENGINE_delete_ptr(fnd->sk, e);
	126	/*
	127	* if 'setdefault', this ENGINE goes to the head of the list
	128	*/
	129	if (!sk_ENGINE_push(fnd->sk, e))
	130	goto end;
	131	/* "touch" this ENGINE_PILE */
	132	fnd->uptodate = 0;
	133	if (setdefault) {
	134	if (!engine_unlocked_init(e)) {
	135	ERR_raise(ERR_LIB_ENGINE, ENGINE_R_INIT_FAILED);
	136	goto end;
	137	}
	138	if (fnd->funct)
	139	engine_unlocked_finish(fnd->funct, 0);
	140	fnd->funct = e;
	141	fnd->uptodate = 1;
	142	}
	143	nids++;
	144	}
	145	ret = 1;
	146	end:
	147	CRYPTO_THREAD_unlock(global_engine_lock);
	148	return ret;
	149	}
	150
	151	static void int_unregister_cb(ENGINE_PILE pile, ENGINE e)
	152	{
	153	int n;
	154	/* Iterate the 'c->sk' stack removing any occurrence of 'e' */
	155	while ((n = sk_ENGINE_find(pile->sk, e)) >= 0) {
	156	(void)sk_ENGINE_delete(pile->sk, n);
	157	pile->uptodate = 0;
	158	}
	159	if (pile->funct == e) {
	160	engine_unlocked_finish(e, 0);
	161	pile->funct = NULL;
	162	}
	163	}
	164
	165	IMPLEMENT_LHASH_DOALL_ARG(ENGINE_PILE, ENGINE);
	166
	167	void engine_table_unregister(ENGINE_TABLE *table, ENGINE e)
	168	{
	169	if (!CRYPTO_THREAD_write_lock(global_engine_lock))
	170	/* Can't return a value. :( */
	171	return;
	172	if (int_table_check(table, 0))
	173	lh_ENGINE_PILE_doall_ENGINE(&(*table)->piles, int_unregister_cb, e);
	174	CRYPTO_THREAD_unlock(global_engine_lock);
	175	}
	176
	177	static void int_cleanup_cb_doall(ENGINE_PILE *p)
	178	{
	179	if (p == NULL)
	180	return;
	181	sk_ENGINE_free(p->sk);
	182	if (p->funct)
	183	engine_unlocked_finish(p->funct, 0);
	184	OPENSSL_free(p);
	185	}
	186
	187	void engine_table_cleanup(ENGINE_TABLE **table)
	188	{
	189	if (!CRYPTO_THREAD_write_lock(global_engine_lock))
	190	return;
	191	if (*table) {
	192	lh_ENGINE_PILE_doall(&(*table)->piles, int_cleanup_cb_doall);
	193	lh_ENGINE_PILE_free(&(*table)->piles);
	194	*table = NULL;
	195	}
	196	CRYPTO_THREAD_unlock(global_engine_lock);
	197	}
	198
	199	/* return a functional reference for a given 'nid' */
	200	ENGINE ossl_engine_table_select(ENGINE_TABLE *table, int nid,
	201	const char *f, int l)
	202	{
	203	ENGINE *ret = NULL;
	204	ENGINE_PILE tmplate, *fnd = NULL;
	205	int initres, loop = 0;
	206
	207	#ifndef OPENSSL_NO_AUTOLOAD_CONFIG
	208	/* Load the config before trying to check if engines are available */
	209	OPENSSL_init_crypto(OPENSSL_INIT_LOAD_CONFIG, NULL);
	210	#endif
	211
	212	if (!(*table)) {
	213	OSSL_TRACE3(ENGINE_TABLE,
	214	"%s:%d, nid=%d, nothing registered!\n",
	215	f, l, nid);
	216	return NULL;
	217	}
	218
	219	if (!CRYPTO_THREAD_write_lock(global_engine_lock))
	220	return NULL;
	221
	222	ERR_set_mark();
	223	/*
	224	* Check again inside the lock otherwise we could race against cleanup
	225	* operations. But don't worry about a debug printout
	226	*/
	227	if (!int_table_check(table, 0))
	228	goto end;
	229	tmplate.nid = nid;
	230	fnd = lh_ENGINE_PILE_retrieve(&(*table)->piles, &tmplate);
	231	if (!fnd)
	232	goto end;
	233	if (fnd->funct && engine_unlocked_init(fnd->funct)) {
	234	OSSL_TRACE4(ENGINE_TABLE,
	235	"%s:%d, nid=%d, using ENGINE '%s' cached\n",
	236	f, l, nid, fnd->funct->id);
	237	ret = fnd->funct;
	238	goto end;
	239	}
	240	if (fnd->uptodate) {
	241	ret = fnd->funct;
	242	goto end;
	243	}
	244	trynext:
	245	ret = sk_ENGINE_value(fnd->sk, loop++);
	246	if (!ret) {
	247	OSSL_TRACE3(ENGINE_TABLE,
	248	"%s:%d, nid=%d, "
	249	"no registered implementations would initialise\n",
	250	f, l, nid);
	251	goto end;
	252	}
	253	/* Try to initialise the ENGINE? */
	254	if ((ret->funct_ref > 0) \|\| !(table_flags & ENGINE_TABLE_FLAG_NOINIT))
	255	initres = engine_unlocked_init(ret);
	256	else
	257	initres = 0;
	258	if (initres) {
	259	/* Update 'funct' */
	260	if ((fnd->funct != ret) && engine_unlocked_init(ret)) {
	261	/* If there was a previous default we release it. */
	262	if (fnd->funct)
	263	engine_unlocked_finish(fnd->funct, 0);
	264	fnd->funct = ret;
	265	OSSL_TRACE4(ENGINE_TABLE,
	266	"%s:%d, nid=%d, setting default to '%s'\n",
	267	f, l, nid, ret->id);
	268	}
	269	OSSL_TRACE4(ENGINE_TABLE,
	270	"%s:%d, nid=%d, using newly initialised '%s'\n",
	271	f, l, nid, ret->id);
	272	goto end;
	273	}
	274	goto trynext;
	275	end:
	276	/*
	277	* If it failed, it is unlikely to succeed again until some future
	278	* registrations have taken place. In all cases, we cache.
	279	*/
	280	if (fnd)
	281	fnd->uptodate = 1;
	282	if (ret)
	283	OSSL_TRACE4(ENGINE_TABLE,
	284	"%s:%d, nid=%d, caching ENGINE '%s'\n",
	285	f, l, nid, ret->id);
	286	else
	287	OSSL_TRACE3(ENGINE_TABLE,
	288	"%s:%d, nid=%d, caching 'no matching ENGINE'\n",
	289	f, l, nid);
	290	CRYPTO_THREAD_unlock(global_engine_lock);
	291	/*
	292	* Whatever happened, any failed init()s are not failures in this
	293	* context, so clear our error state.
	294	*/
	295	ERR_pop_to_mark();
	296	return ret;
	297	}
	298
	299	/* Table enumeration */
	300
	301	static void int_dall(const ENGINE_PILE pile, ENGINE_PILE_DOALL dall)
	302	{
	303	dall->cb(pile->nid, pile->sk, pile->funct, dall->arg);
	304	}
	305
	306	IMPLEMENT_LHASH_DOALL_ARG_CONST(ENGINE_PILE, ENGINE_PILE_DOALL);
	307
	308	void engine_table_doall(ENGINE_TABLE table, engine_table_doall_cb cb,
	309	void *arg)
	310	{
	311	ENGINE_PILE_DOALL dall;
	312	dall.cb = cb;
	313	dall.arg = arg;
	314	if (table)
	315	lh_ENGINE_PILE_doall_ENGINE_PILE_DOALL(&table->piles, int_dall, &dall);
	316	}