1/* $OpenBSD: tasn_fre.c,v 1.23 2023/07/28 10:00:10 tb Exp $ */
2/* Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL
3 * project 2000.
4 */
5/* ====================================================================
6 * Copyright (c) 2000 The OpenSSL Project.  All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 *
12 * 1. Redistributions of source code must retain the above copyright
13 *    notice, this list of conditions and the following disclaimer.
14 *
15 * 2. Redistributions in binary form must reproduce the above copyright
16 *    notice, this list of conditions and the following disclaimer in
17 *    the documentation and/or other materials provided with the
18 *    distribution.
19 *
20 * 3. All advertising materials mentioning features or use of this
21 *    software must display the following acknowledgment:
22 *    "This product includes software developed by the OpenSSL Project
23 *    for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
24 *
25 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
26 *    endorse or promote products derived from this software without
27 *    prior written permission. For written permission, please contact
28 *    licensing@OpenSSL.org.
29 *
30 * 5. Products derived from this software may not be called "OpenSSL"
31 *    nor may "OpenSSL" appear in their names without prior written
32 *    permission of the OpenSSL Project.
33 *
34 * 6. Redistributions of any form whatsoever must retain the following
35 *    acknowledgment:
36 *    "This product includes software developed by the OpenSSL Project
37 *    for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
38 *
39 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
40 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
41 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
42 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
43 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
44 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
45 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
46 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
47 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
48 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
49 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
50 * OF THE POSSIBILITY OF SUCH DAMAGE.
51 * ====================================================================
52 *
53 * This product includes cryptographic software written by Eric Young
54 * (eay@cryptsoft.com).  This product includes software written by Tim
55 * Hudson (tjh@cryptsoft.com).
56 *
57 */
58
59
60#include <stddef.h>
61#include <openssl/asn1.h>
62#include <openssl/asn1t.h>
63#include <openssl/objects.h>
64
65#include "asn1_local.h"
66
67static void asn1_item_free(ASN1_VALUE **pval, const ASN1_ITEM *it);
68
69/* Free up an ASN1 structure */
70
71void
72ASN1_item_free(ASN1_VALUE *val, const ASN1_ITEM *it)
73{
74	asn1_item_free(&val, it);
75}
76LCRYPTO_ALIAS(ASN1_item_free);
77
78void
79ASN1_item_ex_free(ASN1_VALUE **pval, const ASN1_ITEM *it)
80{
81	asn1_item_free(pval, it);
82}
83LCRYPTO_ALIAS(ASN1_item_ex_free);
84
85static void
86asn1_item_free(ASN1_VALUE **pval, const ASN1_ITEM *it)
87{
88	const ASN1_TEMPLATE *tt = NULL, *seqtt;
89	const ASN1_EXTERN_FUNCS *ef;
90	const ASN1_AUX *aux = it->funcs;
91	ASN1_aux_cb *asn1_cb = NULL;
92	int i;
93
94	if (pval == NULL)
95		return;
96	/* For primitive types *pval may be something other than C pointer. */
97	if (it->itype != ASN1_ITYPE_PRIMITIVE && *pval == NULL)
98		return;
99
100	if (aux != NULL && aux->asn1_cb != NULL)
101		asn1_cb = aux->asn1_cb;
102
103	switch (it->itype) {
104	case ASN1_ITYPE_PRIMITIVE:
105		if (it->templates)
106			ASN1_template_free(pval, it->templates);
107		else
108			ASN1_primitive_free(pval, it);
109		break;
110
111	case ASN1_ITYPE_MSTRING:
112		ASN1_primitive_free(pval, it);
113		break;
114
115	case ASN1_ITYPE_CHOICE:
116		if (asn1_cb) {
117			i = asn1_cb(ASN1_OP_FREE_PRE, pval, it, NULL);
118			if (i == 2)
119				return;
120		}
121		i = asn1_get_choice_selector(pval, it);
122		if ((i >= 0) && (i < it->tcount)) {
123			ASN1_VALUE **pchval;
124			tt = it->templates + i;
125			pchval = asn1_get_field_ptr(pval, tt);
126			ASN1_template_free(pchval, tt);
127		}
128		if (asn1_cb)
129			asn1_cb(ASN1_OP_FREE_POST, pval, it, NULL);
130		free(*pval);
131		*pval = NULL;
132		break;
133
134	case ASN1_ITYPE_EXTERN:
135		ef = it->funcs;
136		if (ef && ef->asn1_ex_free)
137			ef->asn1_ex_free(pval, it);
138		break;
139
140	case ASN1_ITYPE_NDEF_SEQUENCE:
141	case ASN1_ITYPE_SEQUENCE:
142		if (asn1_do_lock(pval, -1, it) > 0)
143			return;
144		if (asn1_cb) {
145			i = asn1_cb(ASN1_OP_FREE_PRE, pval, it, NULL);
146			if (i == 2)
147				return;
148		}
149		asn1_enc_cleanup(pval, it);
150		/* If we free up as normal we will invalidate any
151		 * ANY DEFINED BY field and we wont be able to
152		 * determine the type of the field it defines. So
153		 * free up in reverse order.
154		 */
155		tt = it->templates + it->tcount - 1;
156		for (i = 0; i < it->tcount; tt--, i++) {
157			ASN1_VALUE **pseqval;
158			seqtt = asn1_do_adb(pval, tt, 0);
159			if (!seqtt)
160				continue;
161			pseqval = asn1_get_field_ptr(pval, seqtt);
162			ASN1_template_free(pseqval, seqtt);
163		}
164		if (asn1_cb)
165			asn1_cb(ASN1_OP_FREE_POST, pval, it, NULL);
166		free(*pval);
167		*pval = NULL;
168		break;
169	}
170}
171
172void
173ASN1_template_free(ASN1_VALUE **pval, const ASN1_TEMPLATE *tt)
174{
175	int i;
176	if (tt->flags & ASN1_TFLG_SK_MASK) {
177		STACK_OF(ASN1_VALUE) *sk = (STACK_OF(ASN1_VALUE) *)*pval;
178		for (i = 0; i < sk_ASN1_VALUE_num(sk); i++) {
179			ASN1_VALUE *vtmp;
180			vtmp = sk_ASN1_VALUE_value(sk, i);
181			asn1_item_free(&vtmp, tt->item);
182		}
183		sk_ASN1_VALUE_free(sk);
184		*pval = NULL;
185	} else
186		asn1_item_free(pval, tt->item);
187}
188
189void
190ASN1_primitive_free(ASN1_VALUE **pval, const ASN1_ITEM *it)
191{
192	int utype;
193
194	if (it != NULL && it->funcs != NULL) {
195		const ASN1_PRIMITIVE_FUNCS *pf = it->funcs;
196
197		pf->prim_free(pval, it);
198		return;
199	}
200
201	/* Special case: if 'it' is NULL free contents of ASN1_TYPE */
202	if (!it) {
203		ASN1_TYPE *typ = (ASN1_TYPE *)*pval;
204		utype = typ->type;
205		pval = &typ->value.asn1_value;
206		if (!*pval)
207			return;
208	} else if (it->itype == ASN1_ITYPE_MSTRING) {
209		utype = -1;
210		if (!*pval)
211			return;
212	} else {
213		utype = it->utype;
214		if ((utype != V_ASN1_BOOLEAN) && !*pval)
215			return;
216	}
217
218	switch (utype) {
219	case V_ASN1_OBJECT:
220		ASN1_OBJECT_free((ASN1_OBJECT *)*pval);
221		break;
222
223	case V_ASN1_BOOLEAN:
224		if (it)
225			*(ASN1_BOOLEAN *)pval = it->size;
226		else
227			*(ASN1_BOOLEAN *)pval = -1;
228		return;
229
230	case V_ASN1_NULL:
231		break;
232
233	case V_ASN1_ANY:
234		ASN1_primitive_free(pval, NULL);
235		free(*pval);
236		break;
237
238	default:
239		ASN1_STRING_free((ASN1_STRING *)*pval);
240		break;
241	}
242	*pval = NULL;
243}
244