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

/*
 * Copyright 2001-2021 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;
    if (added)
        /* The cleanup callback needs to be added */
        engine_cleanup_add_first(cleanup);
    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 *engine_table_select_int(ENGINE_TABLE **table, int nid, const char *f,
                                int l)
{
    ENGINE *ret = NULL;
    ENGINE_PILE tmplate, *fnd = NULL;
    int initres, loop = 0;

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

    if (!(*table)) {
        OSSL_TRACE3(ENGINE_TABLE,
                   "%s:%d, nid=%d, nothing registered!\n",
                   f, l, nid);
        return NULL;
    }
    ERR_set_mark();
    if (!CRYPTO_THREAD_write_lock(global_engine_lock))
        goto end;
    /*
     * 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
b1322259	1	/*
3c2bdd7d	2	* Copyright 2001-2021 The OpenSSL Project Authors. All Rights Reserved.
b6d1e52d	3	*
3c120f91	4	* Licensed under the Apache License 2.0 (the "License"). You may not use
b1322259 RS	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
b6d1e52d GT	8	*/
b6d1e52d GT	9
b39fc560	10	#include "internal/cryptlib.h"
b6d1e52d	11	#include <openssl/evp.h>
3a87a9b9	12	#include <openssl/lhash.h>
f272be67	13	#include <openssl/trace.h>
706457b7	14	#include "eng_local.h"
b6d1e52d	15
b6d1e52d	16	/* The type of the items in the table */
e6b5c341	17	struct st_engine_pile {
0f113f3e MC	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;
e6b5c341	28	};
3c1d6bbc	29
706457b7	30	/* The type exposed in eng_local.h */
0f113f3e MC	31	struct st_engine_table {
	32	LHASH_OF(ENGINE_PILE) piles;
	33	}; /* ENGINE_TABLE */
b6d1e52d	34
0f113f3e MC	35	typedef struct st_engine_pile_doall {
	36	engine_table_doall_cb *cb;
	37	void *arg;
	38	} ENGINE_PILE_DOALL;
2f0550c4	39
340f5856	40	/* Global flags (ENGINE_TABLE_FLAG_**). /
b6d1e52d GT	41	static unsigned int table_flags = 0;
	42
	43	/* API function manipulating 'table_flags' */
	44	unsigned int ENGINE_get_table_flags(void)
0f113f3e MC	45	{
	46	return table_flags;
	47	}
3c1d6bbc	48
b6d1e52d	49	void ENGINE_set_table_flags(unsigned int flags)
0f113f3e MC	50	{
	51	table_flags = flags;
	52	}
b6d1e52d GT	53
	54	/* Internal functions for the "piles" hash table */
	55	static unsigned long engine_pile_hash(const ENGINE_PILE *c)
0f113f3e MC	56	{
	57	return c->nid;
	58	}
3c1d6bbc	59
b6d1e52d	60	static int engine_pile_cmp(const ENGINE_PILE a, const ENGINE_PILE b)
0f113f3e MC	61	{
	62	return a->nid - b->nid;
	63	}
	64
b6d1e52d	65	static int int_table_check(ENGINE_TABLE **t, int create)
0f113f3e MC	66	{
0f113f3e MC	67	LHASH_OF(ENGINE_PILE) *lh;
3c1d6bbc	68
0f113f3e MC	69	if (*t)
	70	return 1;
	71	if (!create)
	72	return 0;
62d0577e	73	if ((lh = lh_ENGINE_PILE_new(engine_pile_hash, engine_pile_cmp)) == NULL)
0f113f3e MC	74	return 0;
	75	t = (ENGINE_TABLE )lh;
	76	return 1;
	77	}
b6d1e52d	78
0f113f3e	79	/*
706457b7	80	* Privately exposed (via eng_local.h) functions for adding and/or removing
0f113f3e MC	81	* ENGINEs from the implementation table
0f113f3e MC	82	*/
752f2b67	83	int engine_table_register(ENGINE_TABLE *table, ENGINE_CLEANUP_CB cleanup,
0f113f3e MC	84	ENGINE e, const int nids, int num_nids,
	85	int setdefault)
	86	{
	87	int ret = 0, added = 0;
	88	ENGINE_PILE tmplate, *fnd;
cd3f8c1b RS	89
	90	if (!CRYPTO_THREAD_write_lock(global_engine_lock))
	91	return 0;
0f113f3e MC	92	if (!(*table))
	93	added = 1;
	94	if (!int_table_check(table, 1))
	95	goto end;
	96	if (added)
	97	/* The cleanup callback needs to be added */
	98	engine_cleanup_add_first(cleanup);
	99	while (num_nids--) {
	100	tmplate.nid = *nids;
	101	fnd = lh_ENGINE_PILE_retrieve(&(*table)->piles, &tmplate);
	102	if (!fnd) {
b4faea50	103	fnd = OPENSSL_malloc(sizeof(*fnd));
90945fa3	104	if (fnd == NULL)
0f113f3e MC	105	goto end;
	106	fnd->uptodate = 1;
	107	fnd->nid = *nids;
	108	fnd->sk = sk_ENGINE_new_null();
	109	if (!fnd->sk) {
	110	OPENSSL_free(fnd);
	111	goto end;
	112	}
	113	fnd->funct = NULL;
	114	(void)lh_ENGINE_PILE_insert(&(*table)->piles, fnd);
55a7f77d BE	115	if (lh_ENGINE_PILE_retrieve(&(*table)->piles, &tmplate) != fnd) {
	116	sk_ENGINE_free(fnd->sk);
	117	OPENSSL_free(fnd);
	118	goto end;
	119	}
0f113f3e	120	}
0d4fb843	121	/* A registration shouldn't add duplicate entries */
0f113f3e MC	122	(void)sk_ENGINE_delete_ptr(fnd->sk, e);
	123	/*
	124	* if 'setdefault', this ENGINE goes to the head of the list
	125	*/
	126	if (!sk_ENGINE_push(fnd->sk, e))
	127	goto end;
	128	/* "touch" this ENGINE_PILE */
	129	fnd->uptodate = 0;
	130	if (setdefault) {
	131	if (!engine_unlocked_init(e)) {
9311d0c4	132	ERR_raise(ERR_LIB_ENGINE, ENGINE_R_INIT_FAILED);
0f113f3e MC	133	goto end;
	134	}
	135	if (fnd->funct)
	136	engine_unlocked_finish(fnd->funct, 0);
	137	fnd->funct = e;
	138	fnd->uptodate = 1;
	139	}
	140	nids++;
	141	}
	142	ret = 1;
	143	end:
40e068d5	144	CRYPTO_THREAD_unlock(global_engine_lock);
0f113f3e MC	145	return ret;
	146	}
	147
2a056de8	148	static void int_unregister_cb(ENGINE_PILE pile, ENGINE e)
0f113f3e MC	149	{
	150	int n;
	151	/* Iterate the 'c->sk' stack removing any occurrence of 'e' */
	152	while ((n = sk_ENGINE_find(pile->sk, e)) >= 0) {
	153	(void)sk_ENGINE_delete(pile->sk, n);
	154	pile->uptodate = 0;
	155	}
	156	if (pile->funct == e) {
	157	engine_unlocked_finish(e, 0);
	158	pile->funct = NULL;
	159	}
	160	}
	161
2a056de8	162	IMPLEMENT_LHASH_DOALL_ARG(ENGINE_PILE, ENGINE);
3c1d6bbc	163
b6d1e52d	164	void engine_table_unregister(ENGINE_TABLE *table, ENGINE e)
0f113f3e	165	{
cd3f8c1b RS	166	if (!CRYPTO_THREAD_write_lock(global_engine_lock))
	167	/* Can't return a value. :( */
	168	return;
0f113f3e	169	if (int_table_check(table, 0))
2a056de8	170	lh_ENGINE_PILE_doall_ENGINE(&(*table)->piles, int_unregister_cb, e);
40e068d5	171	CRYPTO_THREAD_unlock(global_engine_lock);
0f113f3e	172	}
b6d1e52d	173
3c1d6bbc	174	static void int_cleanup_cb_doall(ENGINE_PILE *p)
0f113f3e	175	{
12a765a5	176	if (p == NULL)
efa7dd64	177	return;
0f113f3e MC	178	sk_ENGINE_free(p->sk);
	179	if (p->funct)
	180	engine_unlocked_finish(p->funct, 0);
	181	OPENSSL_free(p);
	182	}
	183
b6d1e52d	184	void engine_table_cleanup(ENGINE_TABLE **table)
0f113f3e	185	{
cd3f8c1b RS	186	if (!CRYPTO_THREAD_write_lock(global_engine_lock))
cd3f8c1b RS	187	return;
0f113f3e	188	if (*table) {
63c75cd6	189	lh_ENGINE_PILE_doall(&(*table)->piles, int_cleanup_cb_doall);
0f113f3e MC	190	lh_ENGINE_PILE_free(&(*table)->piles);
	191	*table = NULL;
	192	}
40e068d5	193	CRYPTO_THREAD_unlock(global_engine_lock);
0f113f3e	194	}
b6d1e52d	195
340f5856	196	/* return a functional reference for a given 'nid' */
f272be67	197	ENGINE engine_table_select_int(ENGINE_TABLE table, int nid, const char f,
0f113f3e	198	int l)
0f113f3e MC	199	{
	200	ENGINE *ret = NULL;
	201	ENGINE_PILE tmplate, *fnd = NULL;
	202	int initres, loop = 0;
b6d1e52d	203
29dc6e00 MC	204	/* Load the config before trying to check if engines are available */
	205	OPENSSL_init_crypto(OPENSSL_INIT_LOAD_CONFIG, NULL);
	206
0f113f3e	207	if (!(*table)) {
f272be67 RL	208	OSSL_TRACE3(ENGINE_TABLE,
	209	"%s:%d, nid=%d, nothing registered!\n",
	210	f, l, nid);
0f113f3e MC	211	return NULL;
	212	}
	213	ERR_set_mark();
cd3f8c1b RS	214	if (!CRYPTO_THREAD_write_lock(global_engine_lock))
cd3f8c1b RS	215	goto end;
0f113f3e MC	216	/*
0f113f3e MC	217	* Check again inside the lock otherwise we could race against cleanup
f272be67	218	* operations. But don't worry about a debug printout
0f113f3e MC	219	*/
	220	if (!int_table_check(table, 0))
	221	goto end;
	222	tmplate.nid = nid;
	223	fnd = lh_ENGINE_PILE_retrieve(&(*table)->piles, &tmplate);
	224	if (!fnd)
	225	goto end;
	226	if (fnd->funct && engine_unlocked_init(fnd->funct)) {
f272be67 RL	227	OSSL_TRACE4(ENGINE_TABLE,
	228	"%s:%d, nid=%d, using ENGINE '%s' cached\n",
	229	f, l, nid, fnd->funct->id);
0f113f3e MC	230	ret = fnd->funct;
	231	goto end;
	232	}
	233	if (fnd->uptodate) {
	234	ret = fnd->funct;
	235	goto end;
	236	}
	237	trynext:
	238	ret = sk_ENGINE_value(fnd->sk, loop++);
	239	if (!ret) {
f272be67 RL	240	OSSL_TRACE3(ENGINE_TABLE,
	241	"%s:%d, nid=%d, "
	242	"no registered implementations would initialise\n",
	243	f, l, nid);
0f113f3e MC	244	goto end;
	245	}
	246	/* Try to initialise the ENGINE? */
	247	if ((ret->funct_ref > 0) \|\| !(table_flags & ENGINE_TABLE_FLAG_NOINIT))
	248	initres = engine_unlocked_init(ret);
	249	else
	250	initres = 0;
	251	if (initres) {
	252	/* Update 'funct' */
	253	if ((fnd->funct != ret) && engine_unlocked_init(ret)) {
	254	/* If there was a previous default we release it. */
	255	if (fnd->funct)
	256	engine_unlocked_finish(fnd->funct, 0);
	257	fnd->funct = ret;
f272be67 RL	258	OSSL_TRACE4(ENGINE_TABLE,
	259	"%s:%d, nid=%d, setting default to '%s'\n",
	260	f, l, nid, ret->id);
0f113f3e	261	}
f272be67 RL	262	OSSL_TRACE4(ENGINE_TABLE,
	263	"%s:%d, nid=%d, using newly initialised '%s'\n",
	264	f, l, nid, ret->id);
0f113f3e MC	265	goto end;
	266	}
	267	goto trynext;
	268	end:
	269	/*
	270	* If it failed, it is unlikely to succeed again until some future
	271	* registrations have taken place. In all cases, we cache.
	272	*/
	273	if (fnd)
	274	fnd->uptodate = 1;
0f113f3e	275	if (ret)
f272be67 RL	276	OSSL_TRACE4(ENGINE_TABLE,
	277	"%s:%d, nid=%d, caching ENGINE '%s'\n",
	278	f, l, nid, ret->id);
0f113f3e	279	else
f272be67 RL	280	OSSL_TRACE3(ENGINE_TABLE,
	281	"%s:%d, nid=%d, caching 'no matching ENGINE'\n",
	282	f, l, nid);
40e068d5	283	CRYPTO_THREAD_unlock(global_engine_lock);
0f113f3e MC	284	/*
	285	* Whatever happened, any failed init()s are not failures in this
	286	* context, so clear our error state.
	287	*/
	288	ERR_pop_to_mark();
	289	return ret;
	290	}
2f0550c4 DSH	291
	292	/* Table enumeration */
	293
2a056de8	294	static void int_dall(const ENGINE_PILE pile, ENGINE_PILE_DOALL dall)
0f113f3e MC	295	{
	296	dall->cb(pile->nid, pile->sk, pile->funct, dall->arg);
	297	}
	298
2a056de8	299	IMPLEMENT_LHASH_DOALL_ARG_CONST(ENGINE_PILE, ENGINE_PILE_DOALL);
2f0550c4	300
2f0550c4	301	void engine_table_doall(ENGINE_TABLE table, engine_table_doall_cb cb,
0f113f3e MC	302	void *arg)
	303	{
	304	ENGINE_PILE_DOALL dall;
	305	dall.cb = cb;
	306	dall.arg = arg;
	307	if (table)
2a056de8	308	lh_ENGINE_PILE_doall_ENGINE_PILE_DOALL(&table->piles, int_dall, &dall);
0f113f3e	309	}