1 /* crypto/asn1/x_x509.c */
2 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
3  * All rights reserved.
4  *
5  * This package is an SSL implementation written
6  * by Eric Young (eay@cryptsoft.com).
7  * The implementation was written so as to conform with Netscapes SSL.
8  *
9  * This library is free for commercial and non-commercial use as long as
10  * the following conditions are aheared to.  The following conditions
11  * apply to all code found in this distribution, be it the RC4, RSA,
12  * lhash, DES, etc., code; not just the SSL code.  The SSL documentation
13  * included with this distribution is covered by the same copyright terms
14  * except that the holder is Tim Hudson (tjh@cryptsoft.com).
15  *
16  * Copyright remains Eric Young's, and as such any Copyright notices in
17  * the code are not to be removed.
18  * If this package is used in a product, Eric Young should be given attribution
19  * as the author of the parts of the library used.
20  * This can be in the form of a textual message at program startup or
21  * in documentation (online or textual) provided with the package.
22  *
23  * Redistribution and use in source and binary forms, with or without
24  * modification, are permitted provided that the following conditions
25  * are met:
26  * 1. Redistributions of source code must retain the copyright
27  *    notice, this list of conditions and the following disclaimer.
28  * 2. Redistributions in binary form must reproduce the above copyright
29  *    notice, this list of conditions and the following disclaimer in the
30  *    documentation and/or other materials provided with the distribution.
31  * 3. All advertising materials mentioning features or use of this software
32  *    must display the following acknowledgement:
33  *    "This product includes cryptographic software written by
34  *     Eric Young (eay@cryptsoft.com)"
35  *    The word 'cryptographic' can be left out if the rouines from the library
36  *    being used are not cryptographic related :-).
37  * 4. If you include any Windows specific code (or a derivative thereof) from
38  *    the apps directory (application code) you must include an acknowledgement:
39  *    "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
40  *
41  * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
42  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
43  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
44  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
45  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
46  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
47  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
48  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
49  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
50  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
51  * SUCH DAMAGE.
52  *
53  * The licence and distribution terms for any publically available version or
54  * derivative of this code cannot be changed.  i.e. this code cannot simply be
55  * copied and put under another distribution licence
56  * [including the GNU Public Licence.] */
57 
58 #include <assert.h>
59 #include <limits.h>
60 #include <stdio.h>
61 
62 #include <openssl/asn1t.h>
63 #include <openssl/evp.h>
64 #include <openssl/mem.h>
65 #include <openssl/obj.h>
66 #include <openssl/pool.h>
67 #include <openssl/thread.h>
68 #include <openssl/x509.h>
69 #include <openssl/x509v3.h>
70 
71 #include "../internal.h"
72 
73 static CRYPTO_EX_DATA_CLASS g_ex_data_class = CRYPTO_EX_DATA_CLASS_INIT;
74 
75 ASN1_SEQUENCE_enc(X509_CINF, enc, 0) = {
76         ASN1_EXP_OPT(X509_CINF, version, ASN1_INTEGER, 0),
77         ASN1_SIMPLE(X509_CINF, serialNumber, ASN1_INTEGER),
78         ASN1_SIMPLE(X509_CINF, signature, X509_ALGOR),
79         ASN1_SIMPLE(X509_CINF, issuer, X509_NAME),
80         ASN1_SIMPLE(X509_CINF, validity, X509_VAL),
81         ASN1_SIMPLE(X509_CINF, subject, X509_NAME),
82         ASN1_SIMPLE(X509_CINF, key, X509_PUBKEY),
83         ASN1_IMP_OPT(X509_CINF, issuerUID, ASN1_BIT_STRING, 1),
84         ASN1_IMP_OPT(X509_CINF, subjectUID, ASN1_BIT_STRING, 2),
85         ASN1_EXP_SEQUENCE_OF_OPT(X509_CINF, extensions, X509_EXTENSION, 3)
86 } ASN1_SEQUENCE_END_enc(X509_CINF, X509_CINF)
87 
88 IMPLEMENT_ASN1_FUNCTIONS(X509_CINF)
89 /* X509 top level structure needs a bit of customisation */
90 
91 extern void policy_cache_free(X509_POLICY_CACHE *cache);
92 
x509_cb(int operation,ASN1_VALUE ** pval,const ASN1_ITEM * it,void * exarg)93 static int x509_cb(int operation, ASN1_VALUE **pval, const ASN1_ITEM *it,
94                    void *exarg)
95 {
96     X509 *ret = (X509 *)*pval;
97 
98     switch (operation) {
99 
100     case ASN1_OP_NEW_POST:
101         ret->ex_flags = 0;
102         ret->ex_pathlen = -1;
103         ret->skid = NULL;
104         ret->akid = NULL;
105         ret->aux = NULL;
106         ret->crldp = NULL;
107         ret->buf = NULL;
108         CRYPTO_new_ex_data(&ret->ex_data);
109         CRYPTO_MUTEX_init(&ret->lock);
110         break;
111 
112     case ASN1_OP_D2I_PRE:
113         CRYPTO_BUFFER_free(ret->buf);
114         ret->buf = NULL;
115         break;
116 
117     case ASN1_OP_D2I_POST: {
118         /* The version must be one of v1(0), v2(1), or v3(2). */
119         long version = 0;
120         if (ret->cert_info->version != NULL) {
121             version = ASN1_INTEGER_get(ret->cert_info->version);
122             /* TODO(https://crbug.com/boringssl/364): |version| = 0 should also
123              * be rejected. This means an explicitly-encoded X.509v1 version.
124              * v1 is DEFAULT, so DER requires it be omitted. */
125             if (version < 0 || version > 2) {
126                 OPENSSL_PUT_ERROR(X509, X509_R_INVALID_VERSION);
127                 return 0;
128             }
129         }
130 
131         /* Per RFC5280, section 4.1.2.8, these fields require v2 or v3. */
132         if (version == 0 && (ret->cert_info->issuerUID != NULL ||
133                              ret->cert_info->subjectUID != NULL)) {
134             OPENSSL_PUT_ERROR(X509, X509_R_INVALID_FIELD_FOR_VERSION);
135             return 0;
136         }
137 
138         /* Per RFC5280, section 4.1.2.9, extensions require v3. */
139         /* Check disabled. TODO re-enable in Jan 2021.
140            https://crbug.com/boringssl/375
141         if (version != 2 && ret->cert_info->extensions != NULL) {
142             OPENSSL_PUT_ERROR(X509, X509_R_INVALID_FIELD_FOR_VERSION);
143             return 0;
144         }*/
145 
146         break;
147     }
148 
149     case ASN1_OP_FREE_POST:
150         CRYPTO_MUTEX_cleanup(&ret->lock);
151         CRYPTO_free_ex_data(&g_ex_data_class, ret, &ret->ex_data);
152         X509_CERT_AUX_free(ret->aux);
153         ASN1_OCTET_STRING_free(ret->skid);
154         AUTHORITY_KEYID_free(ret->akid);
155         CRL_DIST_POINTS_free(ret->crldp);
156         policy_cache_free(ret->policy_cache);
157         GENERAL_NAMES_free(ret->altname);
158         NAME_CONSTRAINTS_free(ret->nc);
159         CRYPTO_BUFFER_free(ret->buf);
160         break;
161 
162     }
163 
164     return 1;
165 
166 }
167 
168 ASN1_SEQUENCE_ref(X509, x509_cb) = {
169         ASN1_SIMPLE(X509, cert_info, X509_CINF),
170         ASN1_SIMPLE(X509, sig_alg, X509_ALGOR),
171         ASN1_SIMPLE(X509, signature, ASN1_BIT_STRING)
172 } ASN1_SEQUENCE_END_ref(X509, X509)
173 
174 IMPLEMENT_ASN1_FUNCTIONS(X509)
175 
176 IMPLEMENT_ASN1_DUP_FUNCTION(X509)
177 
178 X509 *X509_parse_from_buffer(CRYPTO_BUFFER *buf) {
179   if (CRYPTO_BUFFER_len(buf) > LONG_MAX) {
180     OPENSSL_PUT_ERROR(SSL, ERR_R_OVERFLOW);
181     return 0;
182   }
183 
184   X509 *x509 = X509_new();
185   if (x509 == NULL) {
186     return NULL;
187   }
188 
189   x509->cert_info->enc.alias_only_on_next_parse = 1;
190 
191   const uint8_t *inp = CRYPTO_BUFFER_data(buf);
192   X509 *x509p = x509;
193   X509 *ret = d2i_X509(&x509p, &inp, CRYPTO_BUFFER_len(buf));
194   if (ret == NULL ||
195       inp - CRYPTO_BUFFER_data(buf) != (ptrdiff_t)CRYPTO_BUFFER_len(buf)) {
196     X509_free(x509p);
197     return NULL;
198   }
199   assert(x509p == x509);
200   assert(ret == x509);
201 
202   CRYPTO_BUFFER_up_ref(buf);
203   ret->buf = buf;
204 
205   return ret;
206 }
207 
X509_up_ref(X509 * x)208 int X509_up_ref(X509 *x)
209 {
210     CRYPTO_refcount_inc(&x->references);
211     return 1;
212 }
213 
X509_get_ex_new_index(long argl,void * argp,CRYPTO_EX_unused * unused,CRYPTO_EX_dup * dup_unused,CRYPTO_EX_free * free_func)214 int X509_get_ex_new_index(long argl, void *argp, CRYPTO_EX_unused * unused,
215                           CRYPTO_EX_dup *dup_unused, CRYPTO_EX_free *free_func)
216 {
217     int index;
218     if (!CRYPTO_get_ex_new_index(&g_ex_data_class, &index, argl, argp,
219                                  free_func)) {
220         return -1;
221     }
222     return index;
223 }
224 
X509_set_ex_data(X509 * r,int idx,void * arg)225 int X509_set_ex_data(X509 *r, int idx, void *arg)
226 {
227     return (CRYPTO_set_ex_data(&r->ex_data, idx, arg));
228 }
229 
X509_get_ex_data(X509 * r,int idx)230 void *X509_get_ex_data(X509 *r, int idx)
231 {
232     return (CRYPTO_get_ex_data(&r->ex_data, idx));
233 }
234 
235 /*
236  * X509_AUX ASN1 routines. X509_AUX is the name given to a certificate with
237  * extra info tagged on the end. Since these functions set how a certificate
238  * is trusted they should only be used when the certificate comes from a
239  * reliable source such as local storage.
240  */
241 
d2i_X509_AUX(X509 ** a,const unsigned char ** pp,long length)242 X509 *d2i_X509_AUX(X509 **a, const unsigned char **pp, long length)
243 {
244     const unsigned char *q = *pp;
245     X509 *ret;
246     int freeret = 0;
247 
248     if (!a || *a == NULL)
249         freeret = 1;
250     ret = d2i_X509(a, &q, length);
251     /* If certificate unreadable then forget it */
252     if (!ret)
253         return NULL;
254     /* update length */
255     length -= q - *pp;
256     /* Parse auxiliary information if there is any. */
257     if (length > 0 && !d2i_X509_CERT_AUX(&ret->aux, &q, length))
258         goto err;
259     *pp = q;
260     return ret;
261  err:
262     if (freeret) {
263         X509_free(ret);
264         if (a)
265             *a = NULL;
266     }
267     return NULL;
268 }
269 
270 /*
271  * Serialize trusted certificate to *pp or just return the required buffer
272  * length if pp == NULL.  We ultimately want to avoid modifying *pp in the
273  * error path, but that depends on similar hygiene in lower-level functions.
274  * Here we avoid compounding the problem.
275  */
i2d_x509_aux_internal(X509 * a,unsigned char ** pp)276 static int i2d_x509_aux_internal(X509 *a, unsigned char **pp)
277 {
278     int length, tmplen;
279     unsigned char *start = pp != NULL ? *pp : NULL;
280 
281     assert(pp == NULL || *pp != NULL);
282 
283     /*
284      * This might perturb *pp on error, but fixing that belongs in i2d_X509()
285      * not here.  It should be that if a == NULL length is zero, but we check
286      * both just in case.
287      */
288     length = i2d_X509(a, pp);
289     if (length <= 0 || a == NULL) {
290         return length;
291     }
292 
293     tmplen = i2d_X509_CERT_AUX(a->aux, pp);
294     if (tmplen < 0) {
295         if (start != NULL)
296             *pp = start;
297         return tmplen;
298     }
299     length += tmplen;
300 
301     return length;
302 }
303 
304 /*
305  * Serialize trusted certificate to *pp, or just return the required buffer
306  * length if pp == NULL.
307  *
308  * When pp is not NULL, but *pp == NULL, we allocate the buffer, but since
309  * we're writing two ASN.1 objects back to back, we can't have i2d_X509() do
310  * the allocation, nor can we allow i2d_X509_CERT_AUX() to increment the
311  * allocated buffer.
312  */
i2d_X509_AUX(X509 * a,unsigned char ** pp)313 int i2d_X509_AUX(X509 *a, unsigned char **pp)
314 {
315     int length;
316     unsigned char *tmp;
317 
318     /* Buffer provided by caller */
319     if (pp == NULL || *pp != NULL)
320         return i2d_x509_aux_internal(a, pp);
321 
322     /* Obtain the combined length */
323     if ((length = i2d_x509_aux_internal(a, NULL)) <= 0)
324         return length;
325 
326     /* Allocate requisite combined storage */
327     *pp = tmp = OPENSSL_malloc(length);
328     if (tmp == NULL)
329         return -1; /* Push error onto error stack? */
330 
331     /* Encode, but keep *pp at the originally malloced pointer */
332     length = i2d_x509_aux_internal(a, &tmp);
333     if (length <= 0) {
334         OPENSSL_free(*pp);
335         *pp = NULL;
336     }
337     return length;
338 }
339 
i2d_re_X509_tbs(X509 * x509,unsigned char ** outp)340 int i2d_re_X509_tbs(X509 *x509, unsigned char **outp)
341 {
342     x509->cert_info->enc.modified = 1;
343     return i2d_X509_CINF(x509->cert_info, outp);
344 }
345 
i2d_X509_tbs(X509 * x509,unsigned char ** outp)346 int i2d_X509_tbs(X509 *x509, unsigned char **outp)
347 {
348     return i2d_X509_CINF(x509->cert_info, outp);
349 }
350 
X509_set1_signature_algo(X509 * x509,const X509_ALGOR * algo)351 int X509_set1_signature_algo(X509 *x509, const X509_ALGOR *algo)
352 {
353     /* TODO(davidben): Const-correct generated ASN.1 dup functions.
354      * Alternatively, when the types are hidden and we can embed required fields
355      * directly in structs, import |X509_ALGOR_copy| from upstream. */
356     X509_ALGOR *copy1 = X509_ALGOR_dup((X509_ALGOR *)algo);
357     X509_ALGOR *copy2 = X509_ALGOR_dup((X509_ALGOR *)algo);
358     if (copy1 == NULL || copy2 == NULL) {
359         X509_ALGOR_free(copy1);
360         X509_ALGOR_free(copy2);
361         return 0;
362     }
363 
364     X509_ALGOR_free(x509->sig_alg);
365     x509->sig_alg = copy1;
366     X509_ALGOR_free(x509->cert_info->signature);
367     x509->cert_info->signature = copy2;
368     return 1;
369 }
370 
X509_set1_signature_value(X509 * x509,const uint8_t * sig,size_t sig_len)371 int X509_set1_signature_value(X509 *x509, const uint8_t *sig, size_t sig_len)
372 {
373     if (!ASN1_STRING_set(x509->signature, sig, sig_len)) {
374       return 0;
375     }
376     x509->signature->flags &= ~(ASN1_STRING_FLAG_BITS_LEFT | 0x07);
377     x509->signature->flags |= ASN1_STRING_FLAG_BITS_LEFT;
378     return 1;
379 }
380 
X509_get0_signature(const ASN1_BIT_STRING ** psig,const X509_ALGOR ** palg,const X509 * x)381 void X509_get0_signature(const ASN1_BIT_STRING **psig, const X509_ALGOR **palg,
382                          const X509 *x)
383 {
384     if (psig)
385         *psig = x->signature;
386     if (palg)
387         *palg = x->sig_alg;
388 }
389 
X509_get_signature_nid(const X509 * x)390 int X509_get_signature_nid(const X509 *x)
391 {
392     return OBJ_obj2nid(x->sig_alg->algorithm);
393 }
394