2 * Copyright 2003-2016 The OpenSSL Project Authors. All Rights Reserved.
4 * Licensed under the OpenSSL license (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
11 #include "internal/cryptlib.h"
12 #include "internal/asn1_int.h"
13 #include <openssl/asn1t.h>
14 #include <openssl/conf.h>
15 #include <openssl/x509v3.h>
17 #include "internal/x509_int.h"
20 static void *v2i_NAME_CONSTRAINTS(const X509V3_EXT_METHOD *method,
22 STACK_OF(CONF_VALUE) *nval);
23 static int i2r_NAME_CONSTRAINTS(const X509V3_EXT_METHOD *method, void *a,
25 static int do_i2r_name_constraints(const X509V3_EXT_METHOD *method,
26 STACK_OF(GENERAL_SUBTREE) *trees, BIO *bp,
27 int ind, const char *name);
28 static int print_nc_ipadd(BIO *bp, ASN1_OCTET_STRING *ip);
30 static int nc_match(GENERAL_NAME *gen, NAME_CONSTRAINTS *nc);
31 static int nc_match_single(GENERAL_NAME *sub, GENERAL_NAME *gen);
32 static int nc_dn(X509_NAME *sub, X509_NAME *nm);
33 static int nc_dns(ASN1_IA5STRING *sub, ASN1_IA5STRING *dns);
34 static int nc_email(ASN1_IA5STRING *sub, ASN1_IA5STRING *eml);
35 static int nc_uri(ASN1_IA5STRING *uri, ASN1_IA5STRING *base);
36 static int nc_ip(ASN1_OCTET_STRING *ip, ASN1_OCTET_STRING *base);
38 const X509V3_EXT_METHOD v3_name_constraints = {
39 NID_name_constraints, 0,
40 ASN1_ITEM_ref(NAME_CONSTRAINTS),
43 0, v2i_NAME_CONSTRAINTS,
44 i2r_NAME_CONSTRAINTS, 0,
48 ASN1_SEQUENCE(GENERAL_SUBTREE) = {
49 ASN1_SIMPLE(GENERAL_SUBTREE, base, GENERAL_NAME),
50 ASN1_IMP_OPT(GENERAL_SUBTREE, minimum, ASN1_INTEGER, 0),
51 ASN1_IMP_OPT(GENERAL_SUBTREE, maximum, ASN1_INTEGER, 1)
52 } ASN1_SEQUENCE_END(GENERAL_SUBTREE)
54 ASN1_SEQUENCE(NAME_CONSTRAINTS) = {
55 ASN1_IMP_SEQUENCE_OF_OPT(NAME_CONSTRAINTS, permittedSubtrees,
57 ASN1_IMP_SEQUENCE_OF_OPT(NAME_CONSTRAINTS, excludedSubtrees,
59 } ASN1_SEQUENCE_END(NAME_CONSTRAINTS)
62 IMPLEMENT_ASN1_ALLOC_FUNCTIONS(GENERAL_SUBTREE)
63 IMPLEMENT_ASN1_ALLOC_FUNCTIONS(NAME_CONSTRAINTS)
65 static void *v2i_NAME_CONSTRAINTS(const X509V3_EXT_METHOD *method,
66 X509V3_CTX *ctx, STACK_OF(CONF_VALUE) *nval)
69 CONF_VALUE tval, *val;
70 STACK_OF(GENERAL_SUBTREE) **ptree = NULL;
71 NAME_CONSTRAINTS *ncons = NULL;
72 GENERAL_SUBTREE *sub = NULL;
74 ncons = NAME_CONSTRAINTS_new();
77 for (i = 0; i < sk_CONF_VALUE_num(nval); i++) {
78 val = sk_CONF_VALUE_value(nval, i);
79 if (strncmp(val->name, "permitted", 9) == 0 && val->name[9]) {
80 ptree = &ncons->permittedSubtrees;
81 tval.name = val->name + 10;
82 } else if (strncmp(val->name, "excluded", 8) == 0 && val->name[8]) {
83 ptree = &ncons->excludedSubtrees;
84 tval.name = val->name + 9;
86 X509V3err(X509V3_F_V2I_NAME_CONSTRAINTS, X509V3_R_INVALID_SYNTAX);
89 tval.value = val->value;
90 sub = GENERAL_SUBTREE_new();
93 if (!v2i_GENERAL_NAME_ex(sub->base, method, ctx, &tval, 1))
96 *ptree = sk_GENERAL_SUBTREE_new_null();
97 if (*ptree == NULL || !sk_GENERAL_SUBTREE_push(*ptree, sub))
105 X509V3err(X509V3_F_V2I_NAME_CONSTRAINTS, ERR_R_MALLOC_FAILURE);
107 NAME_CONSTRAINTS_free(ncons);
108 GENERAL_SUBTREE_free(sub);
113 static int i2r_NAME_CONSTRAINTS(const X509V3_EXT_METHOD *method, void *a,
116 NAME_CONSTRAINTS *ncons = a;
117 do_i2r_name_constraints(method, ncons->permittedSubtrees,
118 bp, ind, "Permitted");
119 do_i2r_name_constraints(method, ncons->excludedSubtrees,
120 bp, ind, "Excluded");
124 static int do_i2r_name_constraints(const X509V3_EXT_METHOD *method,
125 STACK_OF(GENERAL_SUBTREE) *trees,
126 BIO *bp, int ind, const char *name)
128 GENERAL_SUBTREE *tree;
130 if (sk_GENERAL_SUBTREE_num(trees) > 0)
131 BIO_printf(bp, "%*s%s:\n", ind, "", name);
132 for (i = 0; i < sk_GENERAL_SUBTREE_num(trees); i++) {
133 tree = sk_GENERAL_SUBTREE_value(trees, i);
134 BIO_printf(bp, "%*s", ind + 2, "");
135 if (tree->base->type == GEN_IPADD)
136 print_nc_ipadd(bp, tree->base->d.ip);
138 GENERAL_NAME_print(bp, tree->base);
144 static int print_nc_ipadd(BIO *bp, ASN1_OCTET_STRING *ip)
152 BIO_printf(bp, "%d.%d.%d.%d/%d.%d.%d.%d",
153 p[0], p[1], p[2], p[3], p[4], p[5], p[6], p[7]);
154 } else if (len == 32) {
155 for (i = 0; i < 16; i++) {
156 BIO_printf(bp, "%X", p[0] << 8 | p[1]);
164 BIO_printf(bp, "IP Address:<invalid>");
169 * Check a certificate conforms to a specified set of constraints.
171 * X509_V_OK: All constraints obeyed.
172 * X509_V_ERR_PERMITTED_VIOLATION: Permitted subtree violation.
173 * X509_V_ERR_EXCLUDED_VIOLATION: Excluded subtree violation.
174 * X509_V_ERR_SUBTREE_MINMAX: Min or max values present and matching type.
175 * X509_V_ERR_UNSUPPORTED_CONSTRAINT_TYPE: Unsupported constraint type.
176 * X509_V_ERR_UNSUPPORTED_CONSTRAINT_SYNTAX: bad unsupported constraint syntax.
177 * X509_V_ERR_UNSUPPORTED_NAME_SYNTAX: bad or unsupported syntax of name
180 int NAME_CONSTRAINTS_check(X509 *x, NAME_CONSTRAINTS *nc)
185 nm = X509_get_subject_name(x);
187 if (X509_NAME_entry_count(nm) > 0) {
189 gntmp.type = GEN_DIRNAME;
190 gntmp.d.directoryName = nm;
192 r = nc_match(&gntmp, nc);
197 gntmp.type = GEN_EMAIL;
199 /* Process any email address attributes in subject name */
203 i = X509_NAME_get_index_by_NID(nm, NID_pkcs9_emailAddress, i);
206 ne = X509_NAME_get_entry(nm, i);
207 gntmp.d.rfc822Name = X509_NAME_ENTRY_get_data(ne);
208 if (gntmp.d.rfc822Name->type != V_ASN1_IA5STRING)
209 return X509_V_ERR_UNSUPPORTED_NAME_SYNTAX;
211 r = nc_match(&gntmp, nc);
219 for (i = 0; i < sk_GENERAL_NAME_num(x->altname); i++) {
220 GENERAL_NAME *gen = sk_GENERAL_NAME_value(x->altname, i);
221 r = nc_match(gen, nc);
230 int NAME_CONSTRAINTS_check_CN(X509 *x, NAME_CONSTRAINTS *nc)
238 stmp.type = V_ASN1_IA5STRING;
239 gntmp.type = GEN_DNS;
240 gntmp.d.dNSName = &stmp;
242 nm = X509_get_subject_name(x);
244 /* Process any commonName attributes in subject name */
249 i = X509_NAME_get_index_by_NID(nm, NID_commonName, i);
252 ne = X509_NAME_get_entry(nm, i);
253 hn = X509_NAME_ENTRY_get_data(ne);
254 /* Only process attributes that look like host names */
255 if (asn1_valid_host(hn)) {
257 int hlen = ASN1_STRING_to_UTF8(&h, hn);
259 return X509_V_ERR_OUT_OF_MEM;
264 r = nc_match(&gntmp, nc);
275 static int nc_match(GENERAL_NAME *gen, NAME_CONSTRAINTS *nc)
277 GENERAL_SUBTREE *sub;
281 * Permitted subtrees: if any subtrees exist of matching the type at
282 * least one subtree must match.
285 for (i = 0; i < sk_GENERAL_SUBTREE_num(nc->permittedSubtrees); i++) {
286 sub = sk_GENERAL_SUBTREE_value(nc->permittedSubtrees, i);
287 if (gen->type != sub->base->type)
289 if (sub->minimum || sub->maximum)
290 return X509_V_ERR_SUBTREE_MINMAX;
291 /* If we already have a match don't bother trying any more */
296 r = nc_match_single(gen, sub->base);
299 else if (r != X509_V_ERR_PERMITTED_VIOLATION)
304 return X509_V_ERR_PERMITTED_VIOLATION;
306 /* Excluded subtrees: must not match any of these */
308 for (i = 0; i < sk_GENERAL_SUBTREE_num(nc->excludedSubtrees); i++) {
309 sub = sk_GENERAL_SUBTREE_value(nc->excludedSubtrees, i);
310 if (gen->type != sub->base->type)
312 if (sub->minimum || sub->maximum)
313 return X509_V_ERR_SUBTREE_MINMAX;
315 r = nc_match_single(gen, sub->base);
317 return X509_V_ERR_EXCLUDED_VIOLATION;
318 else if (r != X509_V_ERR_PERMITTED_VIOLATION)
327 static int nc_match_single(GENERAL_NAME *gen, GENERAL_NAME *base)
329 switch (base->type) {
331 return nc_dn(gen->d.directoryName, base->d.directoryName);
334 return nc_dns(gen->d.dNSName, base->d.dNSName);
337 return nc_email(gen->d.rfc822Name, base->d.rfc822Name);
340 return nc_uri(gen->d.uniformResourceIdentifier,
341 base->d.uniformResourceIdentifier);
344 return nc_ip(gen->d.iPAddress, base->d.iPAddress);
347 return X509_V_ERR_UNSUPPORTED_CONSTRAINT_TYPE;
353 * directoryName name constraint matching. The canonical encoding of
354 * X509_NAME makes this comparison easy. It is matched if the subtree is a
355 * subset of the name.
358 static int nc_dn(X509_NAME *nm, X509_NAME *base)
360 /* Ensure canonical encodings are up to date. */
361 if (nm->modified && i2d_X509_NAME(nm, NULL) < 0)
362 return X509_V_ERR_OUT_OF_MEM;
363 if (base->modified && i2d_X509_NAME(base, NULL) < 0)
364 return X509_V_ERR_OUT_OF_MEM;
365 if (base->canon_enclen > nm->canon_enclen)
366 return X509_V_ERR_PERMITTED_VIOLATION;
367 if (memcmp(base->canon_enc, nm->canon_enc, base->canon_enclen))
368 return X509_V_ERR_PERMITTED_VIOLATION;
372 static int nc_dns(ASN1_IA5STRING *dns, ASN1_IA5STRING *base)
374 char *baseptr = (char *)base->data;
375 char *dnsptr = (char *)dns->data;
376 /* Empty matches everything */
380 * Otherwise can add zero or more components on the left so compare RHS
381 * and if dns is longer and expect '.' as preceding character.
383 if (dns->length > base->length) {
384 dnsptr += dns->length - base->length;
385 if (*baseptr != '.' && dnsptr[-1] != '.')
386 return X509_V_ERR_PERMITTED_VIOLATION;
389 if (strcasecmp(baseptr, dnsptr))
390 return X509_V_ERR_PERMITTED_VIOLATION;
396 static int nc_email(ASN1_IA5STRING *eml, ASN1_IA5STRING *base)
398 const char *baseptr = (char *)base->data;
399 const char *emlptr = (char *)eml->data;
401 const char *baseat = strchr(baseptr, '@');
402 const char *emlat = strchr(emlptr, '@');
404 return X509_V_ERR_UNSUPPORTED_NAME_SYNTAX;
405 /* Special case: initial '.' is RHS match */
406 if (!baseat && (*baseptr == '.')) {
407 if (eml->length > base->length) {
408 emlptr += eml->length - base->length;
409 if (strcasecmp(baseptr, emlptr) == 0)
412 return X509_V_ERR_PERMITTED_VIOLATION;
415 /* If we have anything before '@' match local part */
418 if (baseat != baseptr) {
419 if ((baseat - baseptr) != (emlat - emlptr))
420 return X509_V_ERR_PERMITTED_VIOLATION;
421 /* Case sensitive match of local part */
422 if (strncmp(baseptr, emlptr, emlat - emlptr))
423 return X509_V_ERR_PERMITTED_VIOLATION;
425 /* Position base after '@' */
426 baseptr = baseat + 1;
429 /* Just have hostname left to match: case insensitive */
430 if (strcasecmp(baseptr, emlptr))
431 return X509_V_ERR_PERMITTED_VIOLATION;
437 static int nc_uri(ASN1_IA5STRING *uri, ASN1_IA5STRING *base)
439 const char *baseptr = (char *)base->data;
440 const char *hostptr = (char *)uri->data;
441 const char *p = strchr(hostptr, ':');
443 /* Check for foo:// and skip past it */
444 if (!p || (p[1] != '/') || (p[2] != '/'))
445 return X509_V_ERR_UNSUPPORTED_NAME_SYNTAX;
448 /* Determine length of hostname part of URI */
450 /* Look for a port indicator as end of hostname first */
452 p = strchr(hostptr, ':');
453 /* Otherwise look for trailing slash */
455 p = strchr(hostptr, '/');
458 hostlen = strlen(hostptr);
460 hostlen = p - hostptr;
463 return X509_V_ERR_UNSUPPORTED_NAME_SYNTAX;
465 /* Special case: initial '.' is RHS match */
466 if (*baseptr == '.') {
467 if (hostlen > base->length) {
468 p = hostptr + hostlen - base->length;
469 if (strncasecmp(p, baseptr, base->length) == 0)
472 return X509_V_ERR_PERMITTED_VIOLATION;
475 if ((base->length != (int)hostlen)
476 || strncasecmp(hostptr, baseptr, hostlen))
477 return X509_V_ERR_PERMITTED_VIOLATION;
483 static int nc_ip(ASN1_OCTET_STRING *ip, ASN1_OCTET_STRING *base)
485 int hostlen, baselen, i;
486 unsigned char *hostptr, *baseptr, *maskptr;
488 hostlen = ip->length;
489 baseptr = base->data;
490 baselen = base->length;
492 /* Invalid if not IPv4 or IPv6 */
493 if (!((hostlen == 4) || (hostlen == 16)))
494 return X509_V_ERR_UNSUPPORTED_NAME_SYNTAX;
495 if (!((baselen == 8) || (baselen == 32)))
496 return X509_V_ERR_UNSUPPORTED_NAME_SYNTAX;
498 /* Do not match IPv4 with IPv6 */
499 if (hostlen * 2 != baselen)
500 return X509_V_ERR_PERMITTED_VIOLATION;
502 maskptr = base->data + hostlen;
504 /* Considering possible not aligned base ipAddress */
505 /* Not checking for wrong mask definition: i.e.: 255.0.255.0 */
506 for (i = 0; i < hostlen; i++)
507 if ((hostptr[i] & maskptr[i]) != (baseptr[i] & maskptr[i]))
508 return X509_V_ERR_PERMITTED_VIOLATION;