2 /* Written by Dr Stephen N Henson (shenson@bigfoot.com) for the OpenSSL
5 /* ====================================================================
6 * Copyright (c) 1999-2001 The OpenSSL Project. All rights reserved.
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
12 * 1. Redistributions of source code must retain the above copyright
13 * notice, this list of conditions and the following disclaimer.
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
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/)"
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.
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.
34 * 6. Redistributions of any form whatsoever must retain the following
36 * "This product includes software developed by the OpenSSL Project
37 * for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
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 * ====================================================================
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).
61 #include <openssl/x509v3.h>
62 #include <openssl/x509_vfy.h>
64 static void x509v3_cache_extensions(X509
*x
);
66 static int ca_check(const X509
*x
);
67 static int check_ssl_ca(const X509
*x
);
68 static int check_purpose_ssl_client(const X509_PURPOSE
*xp
, const X509
*x
, int ca
);
69 static int check_purpose_ssl_server(const X509_PURPOSE
*xp
, const X509
*x
, int ca
);
70 static int check_purpose_ns_ssl_server(const X509_PURPOSE
*xp
, const X509
*x
, int ca
);
71 static int purpose_smime(const X509
*x
, int ca
);
72 static int check_purpose_smime_sign(const X509_PURPOSE
*xp
, const X509
*x
, int ca
);
73 static int check_purpose_smime_encrypt(const X509_PURPOSE
*xp
, const X509
*x
, int ca
);
74 static int check_purpose_crl_sign(const X509_PURPOSE
*xp
, const X509
*x
, int ca
);
75 static int no_check(const X509_PURPOSE
*xp
, const X509
*x
, int ca
);
76 static int ocsp_helper(const X509_PURPOSE
*xp
, const X509
*x
, int ca
);
78 static int xp_cmp(const X509_PURPOSE
* const *a
,
79 const X509_PURPOSE
* const *b
);
80 static void xptable_free(X509_PURPOSE
*p
);
82 static X509_PURPOSE xstandard
[] = {
83 {X509_PURPOSE_SSL_CLIENT
, X509_TRUST_SSL_CLIENT
, 0, check_purpose_ssl_client
, "SSL client", "sslclient", NULL
},
84 {X509_PURPOSE_SSL_SERVER
, X509_TRUST_SSL_SERVER
, 0, check_purpose_ssl_server
, "SSL server", "sslserver", NULL
},
85 {X509_PURPOSE_NS_SSL_SERVER
, X509_TRUST_SSL_SERVER
, 0, check_purpose_ns_ssl_server
, "Netscape SSL server", "nssslserver", NULL
},
86 {X509_PURPOSE_SMIME_SIGN
, X509_TRUST_EMAIL
, 0, check_purpose_smime_sign
, "S/MIME signing", "smimesign", NULL
},
87 {X509_PURPOSE_SMIME_ENCRYPT
, X509_TRUST_EMAIL
, 0, check_purpose_smime_encrypt
, "S/MIME encryption", "smimeencrypt", NULL
},
88 {X509_PURPOSE_CRL_SIGN
, X509_TRUST_COMPAT
, 0, check_purpose_crl_sign
, "CRL signing", "crlsign", NULL
},
89 {X509_PURPOSE_ANY
, X509_TRUST_DEFAULT
, 0, no_check
, "Any Purpose", "any", NULL
},
90 {X509_PURPOSE_OCSP_HELPER
, X509_TRUST_COMPAT
, 0, ocsp_helper
, "OCSP helper", "ocsphelper", NULL
},
93 #define X509_PURPOSE_COUNT (sizeof(xstandard)/sizeof(X509_PURPOSE))
95 IMPLEMENT_STACK_OF(X509_PURPOSE
)
97 static STACK_OF(X509_PURPOSE
) *xptable
= NULL
;
99 static int xp_cmp(const X509_PURPOSE
* const *a
,
100 const X509_PURPOSE
* const *b
)
102 return (*a
)->purpose
- (*b
)->purpose
;
105 /* As much as I'd like to make X509_check_purpose use a "const" X509*
106 * I really can't because it does recalculate hashes and do other non-const
108 int X509_check_purpose(X509
*x
, int id
, int ca
)
111 const X509_PURPOSE
*pt
;
112 if(!(x
->ex_flags
& EXFLAG_SET
)) {
113 CRYPTO_w_lock(CRYPTO_LOCK_X509
);
114 x509v3_cache_extensions(x
);
115 CRYPTO_w_unlock(CRYPTO_LOCK_X509
);
117 if(id
== -1) return 1;
118 idx
= X509_PURPOSE_get_by_id(id
);
119 if(idx
== -1) return -1;
120 pt
= X509_PURPOSE_get0(idx
);
121 return pt
->check_purpose(pt
, x
, ca
);
124 int X509_PURPOSE_set(int *p
, int purpose
)
126 if(X509_PURPOSE_get_by_id(purpose
) == -1) {
127 X509V3err(X509V3_F_X509_PURPOSE_SET
, X509V3_R_INVALID_PURPOSE
);
134 int X509_PURPOSE_get_count(void)
136 if(!xptable
) return X509_PURPOSE_COUNT
;
137 return sk_X509_PURPOSE_num(xptable
) + X509_PURPOSE_COUNT
;
140 X509_PURPOSE
* X509_PURPOSE_get0(int idx
)
142 if(idx
< 0) return NULL
;
143 if(idx
< X509_PURPOSE_COUNT
) return xstandard
+ idx
;
144 return sk_X509_PURPOSE_value(xptable
, idx
- X509_PURPOSE_COUNT
);
147 int X509_PURPOSE_get_by_sname(char *sname
)
151 for(i
= 0; i
< X509_PURPOSE_get_count(); i
++) {
152 xptmp
= X509_PURPOSE_get0(i
);
153 if(!strcmp(xptmp
->sname
, sname
)) return i
;
158 int X509_PURPOSE_get_by_id(int purpose
)
162 if((purpose
>= X509_PURPOSE_MIN
) && (purpose
<= X509_PURPOSE_MAX
))
163 return purpose
- X509_PURPOSE_MIN
;
164 tmp
.purpose
= purpose
;
165 if(!xptable
) return -1;
166 idx
= sk_X509_PURPOSE_find(xptable
, &tmp
);
167 if(idx
== -1) return -1;
168 return idx
+ X509_PURPOSE_COUNT
;
171 int X509_PURPOSE_add(int id
, int trust
, int flags
,
172 int (*ck
)(const X509_PURPOSE
*, const X509
*, int),
173 char *name
, char *sname
, void *arg
)
177 /* This is set according to what we change: application can't set it */
178 flags
&= ~X509_PURPOSE_DYNAMIC
;
179 /* This will always be set for application modified trust entries */
180 flags
|= X509_PURPOSE_DYNAMIC_NAME
;
181 /* Get existing entry if any */
182 idx
= X509_PURPOSE_get_by_id(id
);
183 /* Need a new entry */
185 if(!(ptmp
= OPENSSL_malloc(sizeof(X509_PURPOSE
)))) {
186 X509V3err(X509V3_F_X509_PURPOSE_ADD
,ERR_R_MALLOC_FAILURE
);
189 ptmp
->flags
= X509_PURPOSE_DYNAMIC
;
190 } else ptmp
= X509_PURPOSE_get0(idx
);
192 /* OPENSSL_free existing name if dynamic */
193 if(ptmp
->flags
& X509_PURPOSE_DYNAMIC_NAME
) {
194 OPENSSL_free(ptmp
->name
);
195 OPENSSL_free(ptmp
->sname
);
197 /* dup supplied name */
198 ptmp
->name
= BUF_strdup(name
);
199 ptmp
->sname
= BUF_strdup(sname
);
200 if(!ptmp
->name
|| !ptmp
->sname
) {
201 X509V3err(X509V3_F_X509_PURPOSE_ADD
,ERR_R_MALLOC_FAILURE
);
204 /* Keep the dynamic flag of existing entry */
205 ptmp
->flags
&= X509_PURPOSE_DYNAMIC
;
206 /* Set all other flags */
207 ptmp
->flags
|= flags
;
211 ptmp
->check_purpose
= ck
;
212 ptmp
->usr_data
= arg
;
214 /* If its a new entry manage the dynamic table */
216 if(!xptable
&& !(xptable
= sk_X509_PURPOSE_new(xp_cmp
))) {
217 X509V3err(X509V3_F_X509_PURPOSE_ADD
,ERR_R_MALLOC_FAILURE
);
220 if (!sk_X509_PURPOSE_push(xptable
, ptmp
)) {
221 X509V3err(X509V3_F_X509_PURPOSE_ADD
,ERR_R_MALLOC_FAILURE
);
228 static void xptable_free(X509_PURPOSE
*p
)
231 if (p
->flags
& X509_PURPOSE_DYNAMIC
)
233 if (p
->flags
& X509_PURPOSE_DYNAMIC_NAME
) {
234 OPENSSL_free(p
->name
);
235 OPENSSL_free(p
->sname
);
241 void X509_PURPOSE_cleanup(void)
244 sk_X509_PURPOSE_pop_free(xptable
, xptable_free
);
245 for(i
= 0; i
< X509_PURPOSE_COUNT
; i
++) xptable_free(xstandard
+ i
);
249 int X509_PURPOSE_get_id(X509_PURPOSE
*xp
)
254 char *X509_PURPOSE_get0_name(X509_PURPOSE
*xp
)
259 char *X509_PURPOSE_get0_sname(X509_PURPOSE
*xp
)
264 int X509_PURPOSE_get_trust(X509_PURPOSE
*xp
)
269 static int nid_cmp(int *a
, int *b
)
274 int X509_supported_extension(X509_EXTENSION
*ex
)
276 /* This table is a list of the NIDs of supported extensions:
277 * that is those which are used by the verify process. If
278 * an extension is critical and doesn't appear in this list
279 * then the verify process will normally reject the certificate.
280 * The list must be kept in numerical order because it will be
281 * searched using bsearch.
284 static int supported_nids
[] = {
285 NID_netscape_cert_type
, /* 71 */
286 NID_key_usage
, /* 83 */
287 NID_subject_alt_name
, /* 85 */
288 NID_basic_constraints
, /* 87 */
289 NID_ext_key_usage
/* 126 */
294 ex_nid
= OBJ_obj2nid(X509_EXTENSION_get_object(ex
));
296 if (ex_nid
== NID_undef
)
299 if (OBJ_bsearch((char *)&ex_nid
, (char *)supported_nids
,
300 sizeof(supported_nids
)/sizeof(int), sizeof(int),
301 (int (*)(const void *, const void *))nid_cmp
))
307 static void x509v3_cache_extensions(X509
*x
)
309 BASIC_CONSTRAINTS
*bs
;
310 ASN1_BIT_STRING
*usage
;
312 EXTENDED_KEY_USAGE
*extusage
;
316 if(x
->ex_flags
& EXFLAG_SET
) return;
317 #ifndef OPENSSL_NO_SHA
318 X509_digest(x
, EVP_sha1(), x
->sha1_hash
, NULL
);
320 /* Does subject name match issuer ? */
321 if(!X509_NAME_cmp(X509_get_subject_name(x
), X509_get_issuer_name(x
)))
322 x
->ex_flags
|= EXFLAG_SS
;
323 /* V1 should mean no extensions ... */
324 if(!X509_get_version(x
)) x
->ex_flags
|= EXFLAG_V1
;
325 /* Handle basic constraints */
326 if((bs
=X509_get_ext_d2i(x
, NID_basic_constraints
, NULL
, NULL
))) {
327 if(bs
->ca
) x
->ex_flags
|= EXFLAG_CA
;
329 if((bs
->pathlen
->type
== V_ASN1_NEG_INTEGER
)
331 x
->ex_flags
|= EXFLAG_INVALID
;
333 } else x
->ex_pathlen
= ASN1_INTEGER_get(bs
->pathlen
);
334 } else x
->ex_pathlen
= -1;
335 BASIC_CONSTRAINTS_free(bs
);
336 x
->ex_flags
|= EXFLAG_BCONS
;
338 /* Handle key usage */
339 if((usage
=X509_get_ext_d2i(x
, NID_key_usage
, NULL
, NULL
))) {
340 if(usage
->length
> 0) {
341 x
->ex_kusage
= usage
->data
[0];
342 if(usage
->length
> 1)
343 x
->ex_kusage
|= usage
->data
[1] << 8;
344 } else x
->ex_kusage
= 0;
345 x
->ex_flags
|= EXFLAG_KUSAGE
;
346 ASN1_BIT_STRING_free(usage
);
349 if((extusage
=X509_get_ext_d2i(x
, NID_ext_key_usage
, NULL
, NULL
))) {
350 x
->ex_flags
|= EXFLAG_XKUSAGE
;
351 for(i
= 0; i
< sk_ASN1_OBJECT_num(extusage
); i
++) {
352 switch(OBJ_obj2nid(sk_ASN1_OBJECT_value(extusage
,i
))) {
353 case NID_server_auth
:
354 x
->ex_xkusage
|= XKU_SSL_SERVER
;
357 case NID_client_auth
:
358 x
->ex_xkusage
|= XKU_SSL_CLIENT
;
361 case NID_email_protect
:
362 x
->ex_xkusage
|= XKU_SMIME
;
366 x
->ex_xkusage
|= XKU_CODE_SIGN
;
371 x
->ex_xkusage
|= XKU_SGC
;
375 x
->ex_xkusage
|= XKU_OCSP_SIGN
;
379 x
->ex_xkusage
|= XKU_TIMESTAMP
;
383 x
->ex_xkusage
|= XKU_DVCS
;
387 sk_ASN1_OBJECT_pop_free(extusage
, ASN1_OBJECT_free
);
390 if((ns
=X509_get_ext_d2i(x
, NID_netscape_cert_type
, NULL
, NULL
))) {
391 if(ns
->length
> 0) x
->ex_nscert
= ns
->data
[0];
392 else x
->ex_nscert
= 0;
393 x
->ex_flags
|= EXFLAG_NSCERT
;
394 ASN1_BIT_STRING_free(ns
);
396 x
->skid
=X509_get_ext_d2i(x
, NID_subject_key_identifier
, NULL
, NULL
);
397 x
->akid
=X509_get_ext_d2i(x
, NID_authority_key_identifier
, NULL
, NULL
);
398 for (i
= 0; i
< X509_get_ext_count(x
); i
++)
400 ex
= X509_get_ext(x
, i
);
401 if (!X509_EXTENSION_get_critical(ex
))
403 if (!X509_supported_extension(ex
))
405 x
->ex_flags
|= EXFLAG_CRITICAL
;
409 x
->ex_flags
|= EXFLAG_SET
;
412 /* CA checks common to all purposes
416 * 2 basicConstraints absent so "maybe" a CA
417 * 3 basicConstraints absent but self signed V1.
420 #define V1_ROOT (EXFLAG_V1|EXFLAG_SS)
421 #define ku_reject(x, usage) \
422 (((x)->ex_flags & EXFLAG_KUSAGE) && !((x)->ex_kusage & (usage)))
423 #define xku_reject(x, usage) \
424 (((x)->ex_flags & EXFLAG_XKUSAGE) && !((x)->ex_xkusage & (usage)))
425 #define ns_reject(x, usage) \
426 (((x)->ex_flags & EXFLAG_NSCERT) && !((x)->ex_nscert & (usage)))
428 static int ca_check(const X509
*x
)
430 /* keyUsage if present should allow cert signing */
431 if(ku_reject(x
, KU_KEY_CERT_SIGN
)) return 0;
432 if(x
->ex_flags
& EXFLAG_BCONS
) {
433 if(x
->ex_flags
& EXFLAG_CA
) return 1;
434 /* If basicConstraints says not a CA then say so */
437 if((x
->ex_flags
& V1_ROOT
) == V1_ROOT
) return 3;
438 /* If key usage present it must have certSign so tolerate it */
439 else if (x
->ex_flags
& EXFLAG_KUSAGE
) return 3;
444 /* Check SSL CA: common checks for SSL client and server */
445 static int check_ssl_ca(const X509
*x
)
448 ca_ret
= ca_check(x
);
449 if(!ca_ret
) return 0;
450 /* check nsCertType if present */
451 if(x
->ex_flags
& EXFLAG_NSCERT
) {
452 if(x
->ex_nscert
& NS_SSL_CA
) return ca_ret
;
455 if(ca_ret
!= 2) return ca_ret
;
460 static int check_purpose_ssl_client(const X509_PURPOSE
*xp
, const X509
*x
, int ca
)
462 if(xku_reject(x
,XKU_SSL_CLIENT
)) return 0;
463 if(ca
) return check_ssl_ca(x
);
464 /* We need to do digital signatures with it */
465 if(ku_reject(x
,KU_DIGITAL_SIGNATURE
)) return 0;
466 /* nsCertType if present should allow SSL client use */
467 if(ns_reject(x
, NS_SSL_CLIENT
)) return 0;
471 static int check_purpose_ssl_server(const X509_PURPOSE
*xp
, const X509
*x
, int ca
)
473 if(xku_reject(x
,XKU_SSL_SERVER
|XKU_SGC
)) return 0;
474 if(ca
) return check_ssl_ca(x
);
476 if(ns_reject(x
, NS_SSL_SERVER
)) return 0;
477 /* Now as for keyUsage: we'll at least need to sign OR encipher */
478 if(ku_reject(x
, KU_DIGITAL_SIGNATURE
|KU_KEY_ENCIPHERMENT
)) return 0;
484 static int check_purpose_ns_ssl_server(const X509_PURPOSE
*xp
, const X509
*x
, int ca
)
487 ret
= check_purpose_ssl_server(xp
, x
, ca
);
488 if(!ret
|| ca
) return ret
;
489 /* We need to encipher or Netscape complains */
490 if(ku_reject(x
, KU_KEY_ENCIPHERMENT
)) return 0;
494 /* common S/MIME checks */
495 static int purpose_smime(const X509
*x
, int ca
)
497 if(xku_reject(x
,XKU_SMIME
)) return 0;
500 ca_ret
= ca_check(x
);
501 if(!ca_ret
) return 0;
502 /* check nsCertType if present */
503 if(x
->ex_flags
& EXFLAG_NSCERT
) {
504 if(x
->ex_nscert
& NS_SMIME_CA
) return ca_ret
;
507 if(ca_ret
!= 2) return ca_ret
;
510 if(x
->ex_flags
& EXFLAG_NSCERT
) {
511 if(x
->ex_nscert
& NS_SMIME
) return 1;
512 /* Workaround for some buggy certificates */
513 if(x
->ex_nscert
& NS_SSL_CLIENT
) return 2;
519 static int check_purpose_smime_sign(const X509_PURPOSE
*xp
, const X509
*x
, int ca
)
522 ret
= purpose_smime(x
, ca
);
523 if(!ret
|| ca
) return ret
;
524 if(ku_reject(x
, KU_DIGITAL_SIGNATURE
|KU_NON_REPUDIATION
)) return 0;
528 static int check_purpose_smime_encrypt(const X509_PURPOSE
*xp
, const X509
*x
, int ca
)
531 ret
= purpose_smime(x
, ca
);
532 if(!ret
|| ca
) return ret
;
533 if(ku_reject(x
, KU_KEY_ENCIPHERMENT
)) return 0;
537 static int check_purpose_crl_sign(const X509_PURPOSE
*xp
, const X509
*x
, int ca
)
541 if((ca_ret
= ca_check(x
)) != 2) return ca_ret
;
544 if(ku_reject(x
, KU_CRL_SIGN
)) return 0;
548 /* OCSP helper: this is *not* a full OCSP check. It just checks that
549 * each CA is valid. Additional checks must be made on the chain.
552 static int ocsp_helper(const X509_PURPOSE
*xp
, const X509
*x
, int ca
)
554 /* Must be a valid CA */
557 ca_ret
= ca_check(x
);
558 if(ca_ret
!= 2) return ca_ret
;
559 if(x
->ex_flags
& EXFLAG_NSCERT
) {
560 if(x
->ex_nscert
& NS_ANY_CA
) return ca_ret
;
565 /* leaf certificate is checked in OCSP_verify() */
569 static int no_check(const X509_PURPOSE
*xp
, const X509
*x
, int ca
)
574 /* Various checks to see if one certificate issued the second.
575 * This can be used to prune a set of possible issuer certificates
576 * which have been looked up using some simple method such as by
579 * 1. Check issuer_name(subject) == subject_name(issuer)
580 * 2. If akid(subject) exists check it matches issuer
581 * 3. If key_usage(issuer) exists check it supports certificate signing
582 * returns 0 for OK, positive for reason for mismatch, reasons match
583 * codes for X509_verify_cert()
586 int X509_check_issued(X509
*issuer
, X509
*subject
)
588 if(X509_NAME_cmp(X509_get_subject_name(issuer
),
589 X509_get_issuer_name(subject
)))
590 return X509_V_ERR_SUBJECT_ISSUER_MISMATCH
;
591 x509v3_cache_extensions(issuer
);
592 x509v3_cache_extensions(subject
);
594 /* Check key ids (if present) */
595 if(subject
->akid
->keyid
&& issuer
->skid
&&
596 ASN1_OCTET_STRING_cmp(subject
->akid
->keyid
, issuer
->skid
) )
597 return X509_V_ERR_AKID_SKID_MISMATCH
;
598 /* Check serial number */
599 if(subject
->akid
->serial
&&
600 ASN1_INTEGER_cmp(X509_get_serialNumber(issuer
),
601 subject
->akid
->serial
))
602 return X509_V_ERR_AKID_ISSUER_SERIAL_MISMATCH
;
603 /* Check issuer name */
604 if(subject
->akid
->issuer
) {
605 /* Ugh, for some peculiar reason AKID includes
606 * SEQUENCE OF GeneralName. So look for a DirName.
607 * There may be more than one but we only take any
608 * notice of the first.
612 X509_NAME
*nm
= NULL
;
614 gens
= subject
->akid
->issuer
;
615 for(i
= 0; i
< sk_GENERAL_NAME_num(gens
); i
++) {
616 gen
= sk_GENERAL_NAME_value(gens
, i
);
617 if(gen
->type
== GEN_DIRNAME
) {
622 if(nm
&& X509_NAME_cmp(nm
, X509_get_issuer_name(issuer
)))
623 return X509_V_ERR_AKID_ISSUER_SERIAL_MISMATCH
;
626 if(ku_reject(issuer
, KU_KEY_CERT_SIGN
)) return X509_V_ERR_KEYUSAGE_NO_CERTSIGN
;