1/*
2 * Copyright 1999-2018 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/* X509 v3 extension utilities */
11
12#include <stdio.h>
13#include "internal/cryptlib.h"
14#include <openssl/conf.h>
15#include <openssl/x509v3.h>
16
17#include "ext_dat.h"
18
19static STACK_OF(X509V3_EXT_METHOD) *ext_list = NULL;
20
21static int ext_cmp(const X509V3_EXT_METHOD *const *a,
22 const X509V3_EXT_METHOD *const *b);
23static void ext_list_free(X509V3_EXT_METHOD *ext);
24
25int X509V3_EXT_add(X509V3_EXT_METHOD *ext)
26{
27 if (ext_list == NULL
28 && (ext_list = sk_X509V3_EXT_METHOD_new(ext_cmp)) == NULL) {
29 X509V3err(X509V3_F_X509V3_EXT_ADD, ERR_R_MALLOC_FAILURE);
30 return 0;
31 }
32 if (!sk_X509V3_EXT_METHOD_push(ext_list, ext)) {
33 X509V3err(X509V3_F_X509V3_EXT_ADD, ERR_R_MALLOC_FAILURE);
34 return 0;
35 }
36 return 1;
37}
38
39static int ext_cmp(const X509V3_EXT_METHOD *const *a,
40 const X509V3_EXT_METHOD *const *b)
41{
42 return ((*a)->ext_nid - (*b)->ext_nid);
43}
44
45DECLARE_OBJ_BSEARCH_CMP_FN(const X509V3_EXT_METHOD *,
46 const X509V3_EXT_METHOD *, ext);
47IMPLEMENT_OBJ_BSEARCH_CMP_FN(const X509V3_EXT_METHOD *,
48 const X509V3_EXT_METHOD *, ext);
49
50#include "standard_exts.h"
51
52const X509V3_EXT_METHOD *X509V3_EXT_get_nid(int nid)
53{
54 X509V3_EXT_METHOD tmp;
55 const X509V3_EXT_METHOD *t = &tmp, *const *ret;
56 int idx;
57
58 if (nid < 0)
59 return NULL;
60 tmp.ext_nid = nid;
61 ret = OBJ_bsearch_ext(&t, standard_exts, STANDARD_EXTENSION_COUNT);
62 if (ret)
63 return *ret;
64 if (!ext_list)
65 return NULL;
66 idx = sk_X509V3_EXT_METHOD_find(ext_list, &tmp);
67 return sk_X509V3_EXT_METHOD_value(ext_list, idx);
68}
69
70const X509V3_EXT_METHOD *X509V3_EXT_get(X509_EXTENSION *ext)
71{
72 int nid;
73 if ((nid = OBJ_obj2nid(X509_EXTENSION_get_object(ext))) == NID_undef)
74 return NULL;
75 return X509V3_EXT_get_nid(nid);
76}
77
78int X509V3_EXT_add_list(X509V3_EXT_METHOD *extlist)
79{
80 for (; extlist->ext_nid != -1; extlist++)
81 if (!X509V3_EXT_add(extlist))
82 return 0;
83 return 1;
84}
85
86int X509V3_EXT_add_alias(int nid_to, int nid_from)
87{
88 const X509V3_EXT_METHOD *ext;
89 X509V3_EXT_METHOD *tmpext;
90
91 if ((ext = X509V3_EXT_get_nid(nid_from)) == NULL) {
92 X509V3err(X509V3_F_X509V3_EXT_ADD_ALIAS, X509V3_R_EXTENSION_NOT_FOUND);
93 return 0;
94 }
95 if ((tmpext = OPENSSL_malloc(sizeof(*tmpext))) == NULL) {
96 X509V3err(X509V3_F_X509V3_EXT_ADD_ALIAS, ERR_R_MALLOC_FAILURE);
97 return 0;
98 }
99 *tmpext = *ext;
100 tmpext->ext_nid = nid_to;
101 tmpext->ext_flags |= X509V3_EXT_DYNAMIC;
102 return X509V3_EXT_add(tmpext);
103}
104
105void X509V3_EXT_cleanup(void)
106{
107 sk_X509V3_EXT_METHOD_pop_free(ext_list, ext_list_free);
108 ext_list = NULL;
109}
110
111static void ext_list_free(X509V3_EXT_METHOD *ext)
112{
113 if (ext->ext_flags & X509V3_EXT_DYNAMIC)
114 OPENSSL_free(ext);
115}
116
117/*
118 * Legacy function: we don't need to add standard extensions any more because
119 * they are now kept in ext_dat.h.
120 */
121
122int X509V3_add_standard_extensions(void)
123{
124 return 1;
125}
126
127/* Return an extension internal structure */
128
129void *X509V3_EXT_d2i(X509_EXTENSION *ext)
130{
131 const X509V3_EXT_METHOD *method;
132 const unsigned char *p;
133 ASN1_STRING *extvalue;
134 int extlen;
135
136 if ((method = X509V3_EXT_get(ext)) == NULL)
137 return NULL;
138 extvalue = X509_EXTENSION_get_data(ext);
139 p = ASN1_STRING_get0_data(extvalue);
140 extlen = ASN1_STRING_length(extvalue);
141 if (method->it)
142 return ASN1_item_d2i(NULL, &p, extlen, ASN1_ITEM_ptr(method->it));
143 return method->d2i(NULL, &p, extlen);
144}
145
146/*-
147 * Get critical flag and decoded version of extension from a NID.
148 * The "idx" variable returns the last found extension and can
149 * be used to retrieve multiple extensions of the same NID.
150 * However multiple extensions with the same NID is usually
151 * due to a badly encoded certificate so if idx is NULL we
152 * choke if multiple extensions exist.
153 * The "crit" variable is set to the critical value.
154 * The return value is the decoded extension or NULL on
155 * error. The actual error can have several different causes,
156 * the value of *crit reflects the cause:
157 * >= 0, extension found but not decoded (reflects critical value).
158 * -1 extension not found.
159 * -2 extension occurs more than once.
160 */
161
162void *X509V3_get_d2i(const STACK_OF(X509_EXTENSION) *x, int nid, int *crit,
163 int *idx)
164{
165 int lastpos, i;
166 X509_EXTENSION *ex, *found_ex = NULL;
167
168 if (!x) {
169 if (idx)
170 *idx = -1;
171 if (crit)
172 *crit = -1;
173 return NULL;
174 }
175 if (idx)
176 lastpos = *idx + 1;
177 else
178 lastpos = 0;
179 if (lastpos < 0)
180 lastpos = 0;
181 for (i = lastpos; i < sk_X509_EXTENSION_num(x); i++) {
182 ex = sk_X509_EXTENSION_value(x, i);
183 if (OBJ_obj2nid(X509_EXTENSION_get_object(ex)) == nid) {
184 if (idx) {
185 *idx = i;
186 found_ex = ex;
187 break;
188 } else if (found_ex) {
189 /* Found more than one */
190 if (crit)
191 *crit = -2;
192 return NULL;
193 }
194 found_ex = ex;
195 }
196 }
197 if (found_ex) {
198 /* Found it */
199 if (crit)
200 *crit = X509_EXTENSION_get_critical(found_ex);
201 return X509V3_EXT_d2i(found_ex);
202 }
203
204 /* Extension not found */
205 if (idx)
206 *idx = -1;
207 if (crit)
208 *crit = -1;
209 return NULL;
210}
211
212/*
213 * This function is a general extension append, replace and delete utility.
214 * The precise operation is governed by the 'flags' value. The 'crit' and
215 * 'value' arguments (if relevant) are the extensions internal structure.
216 */
217
218int X509V3_add1_i2d(STACK_OF(X509_EXTENSION) **x, int nid, void *value,
219 int crit, unsigned long flags)
220{
221 int errcode, extidx = -1;
222 X509_EXTENSION *ext = NULL, *extmp;
223 STACK_OF(X509_EXTENSION) *ret = NULL;
224 unsigned long ext_op = flags & X509V3_ADD_OP_MASK;
225
226 /*
227 * If appending we don't care if it exists, otherwise look for existing
228 * extension.
229 */
230 if (ext_op != X509V3_ADD_APPEND)
231 extidx = X509v3_get_ext_by_NID(*x, nid, -1);
232
233 /* See if extension exists */
234 if (extidx >= 0) {
235 /* If keep existing, nothing to do */
236 if (ext_op == X509V3_ADD_KEEP_EXISTING)
237 return 1;
238 /* If default then its an error */
239 if (ext_op == X509V3_ADD_DEFAULT) {
240 errcode = X509V3_R_EXTENSION_EXISTS;
241 goto err;
242 }
243 /* If delete, just delete it */
244 if (ext_op == X509V3_ADD_DELETE) {
245 if (!sk_X509_EXTENSION_delete(*x, extidx))
246 return -1;
247 return 1;
248 }
249 } else {
250 /*
251 * If replace existing or delete, error since extension must exist
252 */
253 if ((ext_op == X509V3_ADD_REPLACE_EXISTING) ||
254 (ext_op == X509V3_ADD_DELETE)) {
255 errcode = X509V3_R_EXTENSION_NOT_FOUND;
256 goto err;
257 }
258 }
259
260 /*
261 * If we get this far then we have to create an extension: could have
262 * some flags for alternative encoding schemes...
263 */
264
265 ext = X509V3_EXT_i2d(nid, crit, value);
266
267 if (!ext) {
268 X509V3err(X509V3_F_X509V3_ADD1_I2D,
269 X509V3_R_ERROR_CREATING_EXTENSION);
270 return 0;
271 }
272
273 /* If extension exists replace it.. */
274 if (extidx >= 0) {
275 extmp = sk_X509_EXTENSION_value(*x, extidx);
276 X509_EXTENSION_free(extmp);
277 if (!sk_X509_EXTENSION_set(*x, extidx, ext))
278 return -1;
279 return 1;
280 }
281
282 ret = *x;
283 if (*x == NULL
284 && (ret = sk_X509_EXTENSION_new_null()) == NULL)
285 goto m_fail;
286 if (!sk_X509_EXTENSION_push(ret, ext))
287 goto m_fail;
288
289 *x = ret;
290 return 1;
291
292 m_fail:
293 /* X509V3err(X509V3_F_X509V3_ADD1_I2D, ERR_R_MALLOC_FAILURE); */
294 if (ret != *x)
295 sk_X509_EXTENSION_free(ret);
296 X509_EXTENSION_free(ext);
297 return -1;
298
299 err:
300 if (!(flags & X509V3_ADD_SILENT))
301 X509V3err(X509V3_F_X509V3_ADD1_I2D, errcode);
302 return 0;
303}
304