xref: /openbsd-src/lib/libcrypto/asn1/tasn_fre.c (revision c1a45aed656e7d5627c30c92421893a76f370ccb)
1 /* $OpenBSD: tasn_fre.c,v 1.18 2022/01/07 12:24:17 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_locl.h"
66 
67 static void asn1_item_combine_free(ASN1_VALUE **pval, const ASN1_ITEM *it,
68     int combine);
69 
70 /* Free up an ASN1 structure */
71 
72 void
73 ASN1_item_free(ASN1_VALUE *val, const ASN1_ITEM *it)
74 {
75 	asn1_item_combine_free(&val, it, 0);
76 }
77 
78 void
79 ASN1_item_ex_free(ASN1_VALUE **pval, const ASN1_ITEM *it)
80 {
81 	asn1_item_combine_free(pval, it, 0);
82 }
83 
84 static void
85 asn1_item_combine_free(ASN1_VALUE **pval, const ASN1_ITEM *it, int combine)
86 {
87 	const ASN1_TEMPLATE *tt = NULL, *seqtt;
88 	const ASN1_EXTERN_FUNCS *ef;
89 	const ASN1_AUX *aux = it->funcs;
90 	ASN1_aux_cb *asn1_cb = NULL;
91 	int i;
92 
93 	if (pval == NULL)
94 		return;
95 	/* For primitive types *pval may be something other than C pointer. */
96 	if (it->itype != ASN1_ITYPE_PRIMITIVE && *pval == NULL)
97 		return;
98 
99 	if (aux != NULL && aux->asn1_cb != NULL)
100 		asn1_cb = aux->asn1_cb;
101 
102 	switch (it->itype) {
103 	case ASN1_ITYPE_PRIMITIVE:
104 		if (it->templates)
105 			ASN1_template_free(pval, it->templates);
106 		else
107 			ASN1_primitive_free(pval, it);
108 		break;
109 
110 	case ASN1_ITYPE_MSTRING:
111 		ASN1_primitive_free(pval, it);
112 		break;
113 
114 	case ASN1_ITYPE_CHOICE:
115 		if (asn1_cb) {
116 			i = asn1_cb(ASN1_OP_FREE_PRE, pval, it, NULL);
117 			if (i == 2)
118 				return;
119 		}
120 		i = asn1_get_choice_selector(pval, it);
121 		if ((i >= 0) && (i < it->tcount)) {
122 			ASN1_VALUE **pchval;
123 			tt = it->templates + i;
124 			pchval = asn1_get_field_ptr(pval, tt);
125 			ASN1_template_free(pchval, tt);
126 		}
127 		if (asn1_cb)
128 			asn1_cb(ASN1_OP_FREE_POST, pval, it, NULL);
129 		if (!combine) {
130 			free(*pval);
131 			*pval = NULL;
132 		}
133 		break;
134 
135 	case ASN1_ITYPE_EXTERN:
136 		ef = it->funcs;
137 		if (ef && ef->asn1_ex_free)
138 			ef->asn1_ex_free(pval, it);
139 		break;
140 
141 	case ASN1_ITYPE_NDEF_SEQUENCE:
142 	case ASN1_ITYPE_SEQUENCE:
143 		if (asn1_do_lock(pval, -1, it) > 0)
144 			return;
145 		if (asn1_cb) {
146 			i = asn1_cb(ASN1_OP_FREE_PRE, pval, it, NULL);
147 			if (i == 2)
148 				return;
149 		}
150 		asn1_enc_free(pval, it);
151 		/* If we free up as normal we will invalidate any
152 		 * ANY DEFINED BY field and we wont be able to
153 		 * determine the type of the field it defines. So
154 		 * free up in reverse order.
155 		 */
156 		tt = it->templates + it->tcount - 1;
157 		for (i = 0; i < it->tcount; tt--, i++) {
158 			ASN1_VALUE **pseqval;
159 			seqtt = asn1_do_adb(pval, tt, 0);
160 			if (!seqtt)
161 				continue;
162 			pseqval = asn1_get_field_ptr(pval, seqtt);
163 			ASN1_template_free(pseqval, seqtt);
164 		}
165 		if (asn1_cb)
166 			asn1_cb(ASN1_OP_FREE_POST, pval, it, NULL);
167 		if (!combine) {
168 			free(*pval);
169 			*pval = NULL;
170 		}
171 		break;
172 	}
173 }
174 
175 void
176 ASN1_template_free(ASN1_VALUE **pval, const ASN1_TEMPLATE *tt)
177 {
178 	int i;
179 	if (tt->flags & ASN1_TFLG_SK_MASK) {
180 		STACK_OF(ASN1_VALUE) *sk = (STACK_OF(ASN1_VALUE) *)*pval;
181 		for (i = 0; i < sk_ASN1_VALUE_num(sk); i++) {
182 			ASN1_VALUE *vtmp;
183 			vtmp = sk_ASN1_VALUE_value(sk, i);
184 			asn1_item_combine_free(&vtmp, tt->item,
185 			    0);
186 		}
187 		sk_ASN1_VALUE_free(sk);
188 		*pval = NULL;
189 	} else
190 		asn1_item_combine_free(pval, tt->item,
191 		    tt->flags & ASN1_TFLG_COMBINE);
192 }
193 
194 void
195 ASN1_primitive_free(ASN1_VALUE **pval, const ASN1_ITEM *it)
196 {
197 	int utype;
198 
199 	if (it != NULL && it->funcs != NULL) {
200 		const ASN1_PRIMITIVE_FUNCS *pf = it->funcs;
201 
202 		pf->prim_free(pval, it);
203 		return;
204 	}
205 
206 	/* Special case: if 'it' is NULL free contents of ASN1_TYPE */
207 	if (!it) {
208 		ASN1_TYPE *typ = (ASN1_TYPE *)*pval;
209 		utype = typ->type;
210 		pval = &typ->value.asn1_value;
211 		if (!*pval)
212 			return;
213 	} else if (it->itype == ASN1_ITYPE_MSTRING) {
214 		utype = -1;
215 		if (!*pval)
216 			return;
217 	} else {
218 		utype = it->utype;
219 		if ((utype != V_ASN1_BOOLEAN) && !*pval)
220 			return;
221 	}
222 
223 	switch (utype) {
224 	case V_ASN1_OBJECT:
225 		ASN1_OBJECT_free((ASN1_OBJECT *)*pval);
226 		break;
227 
228 	case V_ASN1_BOOLEAN:
229 		if (it)
230 			*(ASN1_BOOLEAN *)pval = it->size;
231 		else
232 			*(ASN1_BOOLEAN *)pval = -1;
233 		return;
234 
235 	case V_ASN1_NULL:
236 		break;
237 
238 	case V_ASN1_ANY:
239 		ASN1_primitive_free(pval, NULL);
240 		free(*pval);
241 		break;
242 
243 	default:
244 		ASN1_STRING_free((ASN1_STRING *)*pval);
245 		break;
246 	}
247 	*pval = NULL;
248 }
249