1 /*
2 * Copyright 1995-2022 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 #include "internal/deprecated.h"
11
12 #include <stdio.h>
13 #include <time.h>
14 #include <errno.h>
15 #include <limits.h>
16
17 #include "crypto/ctype.h"
18 #include "internal/cryptlib.h"
19 #include <openssl/crypto.h>
20 #include <openssl/buffer.h>
21 #include <openssl/evp.h>
22 #include <openssl/asn1.h>
23 #include <openssl/x509.h>
24 #include <openssl/x509v3.h>
25 #include <openssl/objects.h>
26 #include <openssl/core_names.h>
27 #include "internal/dane.h"
28 #include "crypto/x509.h"
29 #include "x509_local.h"
30
31 /* CRL score values */
32
33 #define CRL_SCORE_NOCRITICAL 0x100 /* No unhandled critical extensions */
34 #define CRL_SCORE_SCOPE 0x080 /* certificate is within CRL scope */
35 #define CRL_SCORE_TIME 0x040 /* CRL times valid */
36 #define CRL_SCORE_ISSUER_NAME 0x020 /* Issuer name matches certificate */
37 #define CRL_SCORE_VALID /* If this score or above CRL is probably valid */ \
38 (CRL_SCORE_NOCRITICAL | CRL_SCORE_TIME | CRL_SCORE_SCOPE)
39 #define CRL_SCORE_ISSUER_CERT 0x018 /* CRL issuer is certificate issuer */
40 #define CRL_SCORE_SAME_PATH 0x008 /* CRL issuer is on certificate path */
41 #define CRL_SCORE_AKID 0x004 /* CRL issuer matches CRL AKID */
42 #define CRL_SCORE_TIME_DELTA 0x002 /* Have a delta CRL with valid times */
43
44 static int build_chain(X509_STORE_CTX *ctx);
45 static int verify_chain(X509_STORE_CTX *ctx);
46 static int dane_verify(X509_STORE_CTX *ctx);
47 static int null_callback(int ok, X509_STORE_CTX *e);
48 static int check_issued(X509_STORE_CTX *ctx, X509 *x, X509 *issuer);
49 static X509 *find_issuer(X509_STORE_CTX *ctx, STACK_OF(X509) *sk, X509 *x);
50 static int check_extensions(X509_STORE_CTX *ctx);
51 static int check_name_constraints(X509_STORE_CTX *ctx);
52 static int check_id(X509_STORE_CTX *ctx);
53 static int check_trust(X509_STORE_CTX *ctx, int num_untrusted);
54 static int check_revocation(X509_STORE_CTX *ctx);
55 static int check_cert(X509_STORE_CTX *ctx);
56 static int check_policy(X509_STORE_CTX *ctx);
57 static int get_issuer_sk(X509 **issuer, X509_STORE_CTX *ctx, X509 *x);
58 static int check_dane_issuer(X509_STORE_CTX *ctx, int depth);
59 static int check_key_level(X509_STORE_CTX *ctx, X509 *cert);
60 static int check_sig_level(X509_STORE_CTX *ctx, X509 *cert);
61 static int check_curve(X509 *cert);
62
63 static int get_crl_score(X509_STORE_CTX *ctx, X509 **pissuer,
64 unsigned int *preasons, X509_CRL *crl, X509 *x);
65 static int get_crl_delta(X509_STORE_CTX *ctx,
66 X509_CRL **pcrl, X509_CRL **pdcrl, X509 *x);
67 static void get_delta_sk(X509_STORE_CTX *ctx, X509_CRL **dcrl,
68 int *pcrl_score, X509_CRL *base,
69 STACK_OF(X509_CRL) *crls);
70 static void crl_akid_check(X509_STORE_CTX *ctx, X509_CRL *crl, X509 **pissuer,
71 int *pcrl_score);
72 static int crl_crldp_check(X509 *x, X509_CRL *crl, int crl_score,
73 unsigned int *preasons);
74 static int check_crl_path(X509_STORE_CTX *ctx, X509 *x);
75 static int check_crl_chain(X509_STORE_CTX *ctx,
76 STACK_OF(X509) *cert_path,
77 STACK_OF(X509) *crl_path);
78
79 static int internal_verify(X509_STORE_CTX *ctx);
80
null_callback(int ok,X509_STORE_CTX * e)81 static int null_callback(int ok, X509_STORE_CTX *e)
82 {
83 return ok;
84 }
85
86 /*-
87 * Return 1 if given cert is considered self-signed, 0 if not, or -1 on error.
88 * This actually verifies self-signedness only if requested.
89 * It calls ossl_x509v3_cache_extensions()
90 * to match issuer and subject names (i.e., the cert being self-issued) and any
91 * present authority key identifier to match the subject key identifier, etc.
92 */
X509_self_signed(X509 * cert,int verify_signature)93 int X509_self_signed(X509 *cert, int verify_signature)
94 {
95 EVP_PKEY *pkey;
96
97 if ((pkey = X509_get0_pubkey(cert)) == NULL) { /* handles cert == NULL */
98 ERR_raise(ERR_LIB_X509, X509_R_UNABLE_TO_GET_CERTS_PUBLIC_KEY);
99 return -1;
100 }
101 if (!ossl_x509v3_cache_extensions(cert))
102 return -1;
103 if ((cert->ex_flags & EXFLAG_SS) == 0)
104 return 0;
105 if (!verify_signature)
106 return 1;
107 return X509_verify(cert, pkey);
108 }
109
110 /*
111 * Given a certificate, try and find an exact match in the store.
112 * Returns 1 on success, 0 on not found, -1 on internal error.
113 */
lookup_cert_match(X509 ** result,X509_STORE_CTX * ctx,X509 * x)114 static int lookup_cert_match(X509 **result, X509_STORE_CTX *ctx, X509 *x)
115 {
116 STACK_OF(X509) *certs;
117 X509 *xtmp = NULL;
118 int i, ret;
119
120 *result = NULL;
121 /* Lookup all certs with matching subject name */
122 ERR_set_mark();
123 certs = ctx->lookup_certs(ctx, X509_get_subject_name(x));
124 ERR_pop_to_mark();
125 if (certs == NULL)
126 return -1;
127 /* Look for exact match */
128 for (i = 0; i < sk_X509_num(certs); i++) {
129 xtmp = sk_X509_value(certs, i);
130 if (X509_cmp(xtmp, x) == 0)
131 break;
132 xtmp = NULL;
133 }
134 ret = xtmp != NULL;
135 if (ret) {
136 if (!X509_up_ref(xtmp))
137 ret = -1;
138 else
139 *result = xtmp;
140 }
141 sk_X509_pop_free(certs, X509_free);
142 return ret;
143 }
144
145 /*-
146 * Inform the verify callback of an error.
147 * The error code is set to |err| if |err| is not X509_V_OK, else
148 * |ctx->error| is left unchanged (under the assumption it is set elsewhere).
149 * The error depth is |depth| if >= 0, else it defaults to |ctx->error_depth|.
150 * The error cert is |x| if not NULL, else defaults to the chain cert at depth.
151 *
152 * Returns 0 to abort verification with an error, non-zero to continue.
153 */
verify_cb_cert(X509_STORE_CTX * ctx,X509 * x,int depth,int err)154 static int verify_cb_cert(X509_STORE_CTX *ctx, X509 *x, int depth, int err)
155 {
156 if (depth < 0)
157 depth = ctx->error_depth;
158 else
159 ctx->error_depth = depth;
160 ctx->current_cert = (x != NULL) ? x : sk_X509_value(ctx->chain, depth);
161 if (err != X509_V_OK)
162 ctx->error = err;
163 return ctx->verify_cb(0, ctx);
164 }
165
166 #define CB_FAIL_IF(cond, ctx, cert, depth, err) \
167 if ((cond) && verify_cb_cert(ctx, cert, depth, err) == 0) \
168 return 0
169
170 /*-
171 * Inform the verify callback of an error, CRL-specific variant. Here, the
172 * error depth and certificate are already set, we just specify the error
173 * number.
174 *
175 * Returns 0 to abort verification with an error, non-zero to continue.
176 */
verify_cb_crl(X509_STORE_CTX * ctx,int err)177 static int verify_cb_crl(X509_STORE_CTX *ctx, int err)
178 {
179 ctx->error = err;
180 return ctx->verify_cb(0, ctx);
181 }
182
check_auth_level(X509_STORE_CTX * ctx)183 static int check_auth_level(X509_STORE_CTX *ctx)
184 {
185 int i;
186 int num = sk_X509_num(ctx->chain);
187
188 if (ctx->param->auth_level <= 0)
189 return 1;
190
191 for (i = 0; i < num; ++i) {
192 X509 *cert = sk_X509_value(ctx->chain, i);
193
194 /*
195 * We've already checked the security of the leaf key, so here we only
196 * check the security of issuer keys.
197 */
198 CB_FAIL_IF(i > 0 && !check_key_level(ctx, cert),
199 ctx, cert, i, X509_V_ERR_CA_KEY_TOO_SMALL);
200 /*
201 * We also check the signature algorithm security of all certificates
202 * except those of the trust anchor at index num-1.
203 */
204 CB_FAIL_IF(i < num - 1 && !check_sig_level(ctx, cert),
205 ctx, cert, i, X509_V_ERR_CA_MD_TOO_WEAK);
206 }
207 return 1;
208 }
209
210 /* Returns -1 on internal error */
verify_chain(X509_STORE_CTX * ctx)211 static int verify_chain(X509_STORE_CTX *ctx)
212 {
213 int err;
214 int ok;
215
216 if ((ok = build_chain(ctx)) <= 0
217 || (ok = check_extensions(ctx)) <= 0
218 || (ok = check_auth_level(ctx)) <= 0
219 || (ok = check_id(ctx)) <= 0
220 || (ok = X509_get_pubkey_parameters(NULL, ctx->chain) ? 1 : -1) <= 0
221 || (ok = ctx->check_revocation(ctx)) <= 0)
222 return ok;
223
224 err = X509_chain_check_suiteb(&ctx->error_depth, NULL, ctx->chain,
225 ctx->param->flags);
226 CB_FAIL_IF(err != X509_V_OK, ctx, NULL, ctx->error_depth, err);
227
228 /* Verify chain signatures and expiration times */
229 ok = ctx->verify != NULL ? ctx->verify(ctx) : internal_verify(ctx);
230 if (ok <= 0)
231 return ok;
232
233 if ((ok = check_name_constraints(ctx)) <= 0)
234 return ok;
235
236 #ifndef OPENSSL_NO_RFC3779
237 /* RFC 3779 path validation, now that CRL check has been done */
238 if ((ok = X509v3_asid_validate_path(ctx)) <= 0)
239 return ok;
240 if ((ok = X509v3_addr_validate_path(ctx)) <= 0)
241 return ok;
242 #endif
243
244 /* If we get this far evaluate policies */
245 if ((ctx->param->flags & X509_V_FLAG_POLICY_CHECK) != 0)
246 ok = ctx->check_policy(ctx);
247 return ok;
248 }
249
X509_STORE_CTX_verify(X509_STORE_CTX * ctx)250 int X509_STORE_CTX_verify(X509_STORE_CTX *ctx)
251 {
252 if (ctx == NULL) {
253 ERR_raise(ERR_LIB_X509, ERR_R_PASSED_NULL_PARAMETER);
254 return -1;
255 }
256 if (ctx->cert == NULL && sk_X509_num(ctx->untrusted) >= 1)
257 ctx->cert = sk_X509_value(ctx->untrusted, 0);
258 return X509_verify_cert(ctx);
259 }
260
X509_verify_cert(X509_STORE_CTX * ctx)261 int X509_verify_cert(X509_STORE_CTX *ctx)
262 {
263 int ret;
264
265 if (ctx == NULL) {
266 ERR_raise(ERR_LIB_X509, ERR_R_PASSED_NULL_PARAMETER);
267 return -1;
268 }
269 if (ctx->cert == NULL) {
270 ERR_raise(ERR_LIB_X509, X509_R_NO_CERT_SET_FOR_US_TO_VERIFY);
271 ctx->error = X509_V_ERR_INVALID_CALL;
272 return -1;
273 }
274
275 if (ctx->chain != NULL) {
276 /*
277 * This X509_STORE_CTX has already been used to verify a cert. We
278 * cannot do another one.
279 */
280 ERR_raise(ERR_LIB_X509, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
281 ctx->error = X509_V_ERR_INVALID_CALL;
282 return -1;
283 }
284
285 if (!ossl_x509_add_cert_new(&ctx->chain, ctx->cert, X509_ADD_FLAG_UP_REF)) {
286 ctx->error = X509_V_ERR_OUT_OF_MEM;
287 return -1;
288 }
289 ctx->num_untrusted = 1;
290
291 /* If the peer's public key is too weak, we can stop early. */
292 CB_FAIL_IF(!check_key_level(ctx, ctx->cert),
293 ctx, ctx->cert, 0, X509_V_ERR_EE_KEY_TOO_SMALL);
294
295 ret = DANETLS_ENABLED(ctx->dane) ? dane_verify(ctx) : verify_chain(ctx);
296
297 /*
298 * Safety-net. If we are returning an error, we must also set ctx->error,
299 * so that the chain is not considered verified should the error be ignored
300 * (e.g. TLS with SSL_VERIFY_NONE).
301 */
302 if (ret <= 0 && ctx->error == X509_V_OK)
303 ctx->error = X509_V_ERR_UNSPECIFIED;
304 return ret;
305 }
306
sk_X509_contains(STACK_OF (X509)* sk,X509 * cert)307 static int sk_X509_contains(STACK_OF(X509) *sk, X509 *cert)
308 {
309 int i, n = sk_X509_num(sk);
310
311 for (i = 0; i < n; i++)
312 if (X509_cmp(sk_X509_value(sk, i), cert) == 0)
313 return 1;
314 return 0;
315 }
316
317 /*
318 * Find in given STACK_OF(X509) |sk| an issuer cert (if any) of given cert |x|.
319 * The issuer must not yet be in |ctx->chain|, yet allowing the exception that
320 * |x| is self-issued and |ctx->chain| has just one element.
321 * Prefer the first non-expired one, else take the most recently expired one.
322 */
find_issuer(X509_STORE_CTX * ctx,STACK_OF (X509)* sk,X509 * x)323 static X509 *find_issuer(X509_STORE_CTX *ctx, STACK_OF(X509) *sk, X509 *x)
324 {
325 int i;
326 X509 *issuer, *rv = NULL;
327
328 for (i = 0; i < sk_X509_num(sk); i++) {
329 issuer = sk_X509_value(sk, i);
330 if (ctx->check_issued(ctx, x, issuer)
331 && (((x->ex_flags & EXFLAG_SI) != 0 && sk_X509_num(ctx->chain) == 1)
332 || !sk_X509_contains(ctx->chain, issuer))) {
333 if (ossl_x509_check_cert_time(ctx, issuer, -1))
334 return issuer;
335 if (rv == NULL || ASN1_TIME_compare(X509_get0_notAfter(issuer),
336 X509_get0_notAfter(rv)) > 0)
337 rv = issuer;
338 }
339 }
340 return rv;
341 }
342
343 /* Check that the given certificate 'x' is issued by the certificate 'issuer' */
check_issued(ossl_unused X509_STORE_CTX * ctx,X509 * x,X509 * issuer)344 static int check_issued(ossl_unused X509_STORE_CTX *ctx, X509 *x, X509 *issuer)
345 {
346 int err = ossl_x509_likely_issued(issuer, x);
347
348 if (err == X509_V_OK)
349 return 1;
350 /*
351 * SUBJECT_ISSUER_MISMATCH just means 'x' is clearly not issued by 'issuer'.
352 * Every other error code likely indicates a real error.
353 */
354 return 0;
355 }
356
357 /*-
358 * Alternative get_issuer method: look up from a STACK_OF(X509) in other_ctx.
359 * Returns -1 on internal error.
360 */
get_issuer_sk(X509 ** issuer,X509_STORE_CTX * ctx,X509 * x)361 static int get_issuer_sk(X509 **issuer, X509_STORE_CTX *ctx, X509 *x)
362 {
363 *issuer = find_issuer(ctx, ctx->other_ctx, x);
364 if (*issuer != NULL)
365 return X509_up_ref(*issuer) ? 1 : -1;
366 return 0;
367 }
368
369 /*-
370 * Alternative lookup method: look from a STACK stored in other_ctx.
371 * Returns NULL on internal error (such as out of memory).
372 */
STACK_OF(X509)373 static STACK_OF(X509) *lookup_certs_sk(X509_STORE_CTX *ctx,
374 const X509_NAME *nm)
375 {
376 STACK_OF(X509) *sk = sk_X509_new_null();
377 X509 *x;
378 int i;
379
380 if (sk == NULL)
381 return NULL;
382 for (i = 0; i < sk_X509_num(ctx->other_ctx); i++) {
383 x = sk_X509_value(ctx->other_ctx, i);
384 if (X509_NAME_cmp(nm, X509_get_subject_name(x)) == 0) {
385 if (!X509_add_cert(sk, x, X509_ADD_FLAG_UP_REF)) {
386 sk_X509_pop_free(sk, X509_free);
387 ctx->error = X509_V_ERR_OUT_OF_MEM;
388 return NULL;
389 }
390 }
391 }
392 return sk;
393 }
394
395 /*
396 * Check EE or CA certificate purpose. For trusted certificates explicit local
397 * auxiliary trust can be used to override EKU-restrictions.
398 * Sadly, returns 0 also on internal error.
399 */
check_purpose(X509_STORE_CTX * ctx,X509 * x,int purpose,int depth,int must_be_ca)400 static int check_purpose(X509_STORE_CTX *ctx, X509 *x, int purpose, int depth,
401 int must_be_ca)
402 {
403 int tr_ok = X509_TRUST_UNTRUSTED;
404
405 /*
406 * For trusted certificates we want to see whether any auxiliary trust
407 * settings trump the purpose constraints.
408 *
409 * This is complicated by the fact that the trust ordinals in
410 * ctx->param->trust are entirely independent of the purpose ordinals in
411 * ctx->param->purpose!
412 *
413 * What connects them is their mutual initialization via calls from
414 * X509_STORE_CTX_set_default() into X509_VERIFY_PARAM_lookup() which sets
415 * related values of both param->trust and param->purpose. It is however
416 * typically possible to infer associated trust values from a purpose value
417 * via the X509_PURPOSE API.
418 *
419 * Therefore, we can only check for trust overrides when the purpose we're
420 * checking is the same as ctx->param->purpose and ctx->param->trust is
421 * also set.
422 */
423 if (depth >= ctx->num_untrusted && purpose == ctx->param->purpose)
424 tr_ok = X509_check_trust(x, ctx->param->trust, X509_TRUST_NO_SS_COMPAT);
425
426 switch (tr_ok) {
427 case X509_TRUST_TRUSTED:
428 return 1;
429 case X509_TRUST_REJECTED:
430 break;
431 default:
432 switch (X509_check_purpose(x, purpose, must_be_ca > 0)) {
433 case 1:
434 return 1;
435 case 0:
436 break;
437 default:
438 if ((ctx->param->flags & X509_V_FLAG_X509_STRICT) == 0)
439 return 1;
440 }
441 break;
442 }
443
444 return verify_cb_cert(ctx, x, depth, X509_V_ERR_INVALID_PURPOSE);
445 }
446
447 /*
448 * Check extensions of a cert chain for consistency with the supplied purpose.
449 * Sadly, returns 0 also on internal error.
450 */
check_extensions(X509_STORE_CTX * ctx)451 static int check_extensions(X509_STORE_CTX *ctx)
452 {
453 int i, must_be_ca, plen = 0;
454 X509 *x;
455 int ret, proxy_path_length = 0;
456 int purpose, allow_proxy_certs, num = sk_X509_num(ctx->chain);
457
458 /*-
459 * must_be_ca can have 1 of 3 values:
460 * -1: we accept both CA and non-CA certificates, to allow direct
461 * use of self-signed certificates (which are marked as CA).
462 * 0: we only accept non-CA certificates. This is currently not
463 * used, but the possibility is present for future extensions.
464 * 1: we only accept CA certificates. This is currently used for
465 * all certificates in the chain except the leaf certificate.
466 */
467 must_be_ca = -1;
468
469 /* CRL path validation */
470 if (ctx->parent != NULL) {
471 allow_proxy_certs = 0;
472 purpose = X509_PURPOSE_CRL_SIGN;
473 } else {
474 allow_proxy_certs =
475 (ctx->param->flags & X509_V_FLAG_ALLOW_PROXY_CERTS) != 0;
476 purpose = ctx->param->purpose;
477 }
478
479 for (i = 0; i < num; i++) {
480 x = sk_X509_value(ctx->chain, i);
481 CB_FAIL_IF((ctx->param->flags & X509_V_FLAG_IGNORE_CRITICAL) == 0
482 && (x->ex_flags & EXFLAG_CRITICAL) != 0,
483 ctx, x, i, X509_V_ERR_UNHANDLED_CRITICAL_EXTENSION);
484 CB_FAIL_IF(!allow_proxy_certs && (x->ex_flags & EXFLAG_PROXY) != 0,
485 ctx, x, i, X509_V_ERR_PROXY_CERTIFICATES_NOT_ALLOWED);
486 ret = X509_check_ca(x);
487 switch (must_be_ca) {
488 case -1:
489 CB_FAIL_IF((ctx->param->flags & X509_V_FLAG_X509_STRICT) != 0
490 && ret != 1 && ret != 0,
491 ctx, x, i, X509_V_ERR_INVALID_CA);
492 break;
493 case 0:
494 CB_FAIL_IF(ret != 0, ctx, x, i, X509_V_ERR_INVALID_NON_CA);
495 break;
496 default:
497 /* X509_V_FLAG_X509_STRICT is implicit for intermediate CAs */
498 CB_FAIL_IF(ret == 0
499 || ((i + 1 < num
500 || (ctx->param->flags & X509_V_FLAG_X509_STRICT) != 0)
501 && ret != 1), ctx, x, i, X509_V_ERR_INVALID_CA);
502 break;
503 }
504 if (num > 1) {
505 /* Check for presence of explicit elliptic curve parameters */
506 ret = check_curve(x);
507 CB_FAIL_IF(ret < 0, ctx, x, i, X509_V_ERR_UNSPECIFIED);
508 CB_FAIL_IF(ret == 0, ctx, x, i, X509_V_ERR_EC_KEY_EXPLICIT_PARAMS);
509 }
510 /*
511 * Do the following set of checks only if strict checking is requested
512 * and not for self-issued (including self-signed) EE (non-CA) certs
513 * because RFC 5280 does not apply to them according RFC 6818 section 2.
514 */
515 if ((ctx->param->flags & X509_V_FLAG_X509_STRICT) != 0
516 && num > 1) { /*
517 * this should imply
518 * !(i == 0 && (x->ex_flags & EXFLAG_CA) == 0
519 * && (x->ex_flags & EXFLAG_SI) != 0)
520 */
521 /* Check Basic Constraints according to RFC 5280 section 4.2.1.9 */
522 if (x->ex_pathlen != -1) {
523 CB_FAIL_IF((x->ex_flags & EXFLAG_CA) == 0,
524 ctx, x, i, X509_V_ERR_PATHLEN_INVALID_FOR_NON_CA);
525 CB_FAIL_IF((x->ex_kusage & KU_KEY_CERT_SIGN) == 0, ctx,
526 x, i, X509_V_ERR_PATHLEN_WITHOUT_KU_KEY_CERT_SIGN);
527 }
528 CB_FAIL_IF((x->ex_flags & EXFLAG_CA) != 0
529 && (x->ex_flags & EXFLAG_BCONS) != 0
530 && (x->ex_flags & EXFLAG_BCONS_CRITICAL) == 0,
531 ctx, x, i, X509_V_ERR_CA_BCONS_NOT_CRITICAL);
532 /* Check Key Usage according to RFC 5280 section 4.2.1.3 */
533 if ((x->ex_flags & EXFLAG_CA) != 0) {
534 CB_FAIL_IF((x->ex_flags & EXFLAG_KUSAGE) == 0,
535 ctx, x, i, X509_V_ERR_CA_CERT_MISSING_KEY_USAGE);
536 } else {
537 CB_FAIL_IF((x->ex_kusage & KU_KEY_CERT_SIGN) != 0, ctx, x, i,
538 X509_V_ERR_KU_KEY_CERT_SIGN_INVALID_FOR_NON_CA);
539 }
540 /* Check issuer is non-empty acc. to RFC 5280 section 4.1.2.4 */
541 CB_FAIL_IF(X509_NAME_entry_count(X509_get_issuer_name(x)) == 0,
542 ctx, x, i, X509_V_ERR_ISSUER_NAME_EMPTY);
543 /* Check subject is non-empty acc. to RFC 5280 section 4.1.2.6 */
544 CB_FAIL_IF(((x->ex_flags & EXFLAG_CA) != 0
545 || (x->ex_kusage & KU_CRL_SIGN) != 0
546 || x->altname == NULL)
547 && X509_NAME_entry_count(X509_get_subject_name(x)) == 0,
548 ctx, x, i, X509_V_ERR_SUBJECT_NAME_EMPTY);
549 CB_FAIL_IF(X509_NAME_entry_count(X509_get_subject_name(x)) == 0
550 && x->altname != NULL
551 && (x->ex_flags & EXFLAG_SAN_CRITICAL) == 0,
552 ctx, x, i, X509_V_ERR_EMPTY_SUBJECT_SAN_NOT_CRITICAL);
553 /* Check SAN is non-empty according to RFC 5280 section 4.2.1.6 */
554 CB_FAIL_IF(x->altname != NULL
555 && sk_GENERAL_NAME_num(x->altname) <= 0,
556 ctx, x, i, X509_V_ERR_EMPTY_SUBJECT_ALT_NAME);
557 /* Check sig alg consistency acc. to RFC 5280 section 4.1.1.2 */
558 CB_FAIL_IF(X509_ALGOR_cmp(&x->sig_alg, &x->cert_info.signature) != 0,
559 ctx, x, i, X509_V_ERR_SIGNATURE_ALGORITHM_INCONSISTENCY);
560 CB_FAIL_IF(x->akid != NULL
561 && (x->ex_flags & EXFLAG_AKID_CRITICAL) != 0,
562 ctx, x, i, X509_V_ERR_AUTHORITY_KEY_IDENTIFIER_CRITICAL);
563 CB_FAIL_IF(x->skid != NULL
564 && (x->ex_flags & EXFLAG_SKID_CRITICAL) != 0,
565 ctx, x, i, X509_V_ERR_SUBJECT_KEY_IDENTIFIER_CRITICAL);
566 if (X509_get_version(x) >= X509_VERSION_3) {
567 /* Check AKID presence acc. to RFC 5280 section 4.2.1.1 */
568 CB_FAIL_IF(i + 1 < num /*
569 * this means not last cert in chain,
570 * taken as "generated by conforming CAs"
571 */
572 && (x->akid == NULL || x->akid->keyid == NULL), ctx,
573 x, i, X509_V_ERR_MISSING_AUTHORITY_KEY_IDENTIFIER);
574 /* Check SKID presence acc. to RFC 5280 section 4.2.1.2 */
575 CB_FAIL_IF((x->ex_flags & EXFLAG_CA) != 0 && x->skid == NULL,
576 ctx, x, i, X509_V_ERR_MISSING_SUBJECT_KEY_IDENTIFIER);
577 } else {
578 CB_FAIL_IF(sk_X509_EXTENSION_num(X509_get0_extensions(x)) > 0,
579 ctx, x, i, X509_V_ERR_EXTENSIONS_REQUIRE_VERSION_3);
580 }
581 }
582
583 /* check_purpose() makes the callback as needed */
584 if (purpose > 0 && !check_purpose(ctx, x, purpose, i, must_be_ca))
585 return 0;
586 /* Check path length */
587 CB_FAIL_IF(i > 1 && x->ex_pathlen != -1
588 && plen > x->ex_pathlen + proxy_path_length,
589 ctx, x, i, X509_V_ERR_PATH_LENGTH_EXCEEDED);
590 /* Increment path length if not a self-issued intermediate CA */
591 if (i > 0 && (x->ex_flags & EXFLAG_SI) == 0)
592 plen++;
593 /*
594 * If this certificate is a proxy certificate, the next certificate
595 * must be another proxy certificate or a EE certificate. If not,
596 * the next certificate must be a CA certificate.
597 */
598 if (x->ex_flags & EXFLAG_PROXY) {
599 /*
600 * RFC3820, 4.1.3 (b)(1) stipulates that if pCPathLengthConstraint
601 * is less than max_path_length, the former should be copied to
602 * the latter, and 4.1.4 (a) stipulates that max_path_length
603 * should be verified to be larger than zero and decrement it.
604 *
605 * Because we're checking the certs in the reverse order, we start
606 * with verifying that proxy_path_length isn't larger than pcPLC,
607 * and copy the latter to the former if it is, and finally,
608 * increment proxy_path_length.
609 */
610 if (x->ex_pcpathlen != -1) {
611 CB_FAIL_IF(proxy_path_length > x->ex_pcpathlen,
612 ctx, x, i, X509_V_ERR_PROXY_PATH_LENGTH_EXCEEDED);
613 proxy_path_length = x->ex_pcpathlen;
614 }
615 proxy_path_length++;
616 must_be_ca = 0;
617 } else {
618 must_be_ca = 1;
619 }
620 }
621 return 1;
622 }
623
has_san_id(X509 * x,int gtype)624 static int has_san_id(X509 *x, int gtype)
625 {
626 int i;
627 int ret = 0;
628 GENERAL_NAMES *gs = X509_get_ext_d2i(x, NID_subject_alt_name, NULL, NULL);
629
630 if (gs == NULL)
631 return 0;
632
633 for (i = 0; i < sk_GENERAL_NAME_num(gs); i++) {
634 GENERAL_NAME *g = sk_GENERAL_NAME_value(gs, i);
635
636 if (g->type == gtype) {
637 ret = 1;
638 break;
639 }
640 }
641 GENERAL_NAMES_free(gs);
642 return ret;
643 }
644
645 /* Returns -1 on internal error */
check_name_constraints(X509_STORE_CTX * ctx)646 static int check_name_constraints(X509_STORE_CTX *ctx)
647 {
648 int i;
649
650 /* Check name constraints for all certificates */
651 for (i = sk_X509_num(ctx->chain) - 1; i >= 0; i--) {
652 X509 *x = sk_X509_value(ctx->chain, i);
653 int j;
654
655 /* Ignore self-issued certs unless last in chain */
656 if (i != 0 && (x->ex_flags & EXFLAG_SI) != 0)
657 continue;
658
659 /*
660 * Proxy certificates policy has an extra constraint, where the
661 * certificate subject MUST be the issuer with a single CN entry
662 * added.
663 * (RFC 3820: 3.4, 4.1.3 (a)(4))
664 */
665 if ((x->ex_flags & EXFLAG_PROXY) != 0) {
666 X509_NAME *tmpsubject = X509_get_subject_name(x);
667 X509_NAME *tmpissuer = X509_get_issuer_name(x);
668 X509_NAME_ENTRY *tmpentry = NULL;
669 int last_nid = 0;
670 int err = X509_V_OK;
671 int last_loc = X509_NAME_entry_count(tmpsubject) - 1;
672
673 /* Check that there are at least two RDNs */
674 if (last_loc < 1) {
675 err = X509_V_ERR_PROXY_SUBJECT_NAME_VIOLATION;
676 goto proxy_name_done;
677 }
678
679 /*
680 * Check that there is exactly one more RDN in subject as
681 * there is in issuer.
682 */
683 if (X509_NAME_entry_count(tmpsubject)
684 != X509_NAME_entry_count(tmpissuer) + 1) {
685 err = X509_V_ERR_PROXY_SUBJECT_NAME_VIOLATION;
686 goto proxy_name_done;
687 }
688
689 /*
690 * Check that the last subject component isn't part of a
691 * multi-valued RDN
692 */
693 if (X509_NAME_ENTRY_set(X509_NAME_get_entry(tmpsubject, last_loc))
694 == X509_NAME_ENTRY_set(X509_NAME_get_entry(tmpsubject,
695 last_loc - 1))) {
696 err = X509_V_ERR_PROXY_SUBJECT_NAME_VIOLATION;
697 goto proxy_name_done;
698 }
699
700 /*
701 * Check that the last subject RDN is a commonName, and that
702 * all the previous RDNs match the issuer exactly
703 */
704 tmpsubject = X509_NAME_dup(tmpsubject);
705 if (tmpsubject == NULL) {
706 ERR_raise(ERR_LIB_X509, ERR_R_MALLOC_FAILURE);
707 ctx->error = X509_V_ERR_OUT_OF_MEM;
708 return -1;
709 }
710
711 tmpentry = X509_NAME_delete_entry(tmpsubject, last_loc);
712 last_nid = OBJ_obj2nid(X509_NAME_ENTRY_get_object(tmpentry));
713
714 if (last_nid != NID_commonName
715 || X509_NAME_cmp(tmpsubject, tmpissuer) != 0) {
716 err = X509_V_ERR_PROXY_SUBJECT_NAME_VIOLATION;
717 }
718
719 X509_NAME_ENTRY_free(tmpentry);
720 X509_NAME_free(tmpsubject);
721
722 proxy_name_done:
723 CB_FAIL_IF(err != X509_V_OK, ctx, x, i, err);
724 }
725
726 /*
727 * Check against constraints for all certificates higher in chain
728 * including trust anchor. Trust anchor not strictly speaking needed
729 * but if it includes constraints it is to be assumed it expects them
730 * to be obeyed.
731 */
732 for (j = sk_X509_num(ctx->chain) - 1; j > i; j--) {
733 NAME_CONSTRAINTS *nc = sk_X509_value(ctx->chain, j)->nc;
734
735 if (nc) {
736 int rv = NAME_CONSTRAINTS_check(x, nc);
737 int ret = 1;
738
739 /* If EE certificate check commonName too */
740 if (rv == X509_V_OK && i == 0
741 && (ctx->param->hostflags
742 & X509_CHECK_FLAG_NEVER_CHECK_SUBJECT) == 0
743 && ((ctx->param->hostflags
744 & X509_CHECK_FLAG_ALWAYS_CHECK_SUBJECT) != 0
745 || (ret = has_san_id(x, GEN_DNS)) == 0))
746 rv = NAME_CONSTRAINTS_check_CN(x, nc);
747 if (ret < 0)
748 return ret;
749
750 switch (rv) {
751 case X509_V_OK:
752 break;
753 case X509_V_ERR_OUT_OF_MEM:
754 return -1;
755 default:
756 CB_FAIL_IF(1, ctx, x, i, rv);
757 break;
758 }
759 }
760 }
761 }
762 return 1;
763 }
764
check_id_error(X509_STORE_CTX * ctx,int errcode)765 static int check_id_error(X509_STORE_CTX *ctx, int errcode)
766 {
767 return verify_cb_cert(ctx, ctx->cert, 0, errcode);
768 }
769
check_hosts(X509 * x,X509_VERIFY_PARAM * vpm)770 static int check_hosts(X509 *x, X509_VERIFY_PARAM *vpm)
771 {
772 int i;
773 int n = sk_OPENSSL_STRING_num(vpm->hosts);
774 char *name;
775
776 if (vpm->peername != NULL) {
777 OPENSSL_free(vpm->peername);
778 vpm->peername = NULL;
779 }
780 for (i = 0; i < n; ++i) {
781 name = sk_OPENSSL_STRING_value(vpm->hosts, i);
782 if (X509_check_host(x, name, 0, vpm->hostflags, &vpm->peername) > 0)
783 return 1;
784 }
785 return n == 0;
786 }
787
check_id(X509_STORE_CTX * ctx)788 static int check_id(X509_STORE_CTX *ctx)
789 {
790 X509_VERIFY_PARAM *vpm = ctx->param;
791 X509 *x = ctx->cert;
792
793 if (vpm->hosts != NULL && check_hosts(x, vpm) <= 0) {
794 if (!check_id_error(ctx, X509_V_ERR_HOSTNAME_MISMATCH))
795 return 0;
796 }
797 if (vpm->email != NULL
798 && X509_check_email(x, vpm->email, vpm->emaillen, 0) <= 0) {
799 if (!check_id_error(ctx, X509_V_ERR_EMAIL_MISMATCH))
800 return 0;
801 }
802 if (vpm->ip != NULL && X509_check_ip(x, vpm->ip, vpm->iplen, 0) <= 0) {
803 if (!check_id_error(ctx, X509_V_ERR_IP_ADDRESS_MISMATCH))
804 return 0;
805 }
806 return 1;
807 }
808
809 /* Returns -1 on internal error */
check_trust(X509_STORE_CTX * ctx,int num_untrusted)810 static int check_trust(X509_STORE_CTX *ctx, int num_untrusted)
811 {
812 int i, res;
813 X509 *x = NULL;
814 X509 *mx;
815 SSL_DANE *dane = ctx->dane;
816 int num = sk_X509_num(ctx->chain);
817 int trust;
818
819 /*
820 * Check for a DANE issuer at depth 1 or greater, if it is a DANE-TA(2)
821 * match, we're done, otherwise we'll merely record the match depth.
822 */
823 if (DANETLS_HAS_TA(dane) && num_untrusted > 0 && num_untrusted < num) {
824 trust = check_dane_issuer(ctx, num_untrusted);
825 if (trust != X509_TRUST_UNTRUSTED)
826 return trust;
827 }
828
829 /*
830 * Check trusted certificates in chain at depth num_untrusted and up.
831 * Note, that depths 0..num_untrusted-1 may also contain trusted
832 * certificates, but the caller is expected to have already checked those,
833 * and wants to incrementally check just any added since.
834 */
835 for (i = num_untrusted; i < num; i++) {
836 x = sk_X509_value(ctx->chain, i);
837 trust = X509_check_trust(x, ctx->param->trust, 0);
838 /* If explicitly trusted (so not neutral nor rejected) return trusted */
839 if (trust == X509_TRUST_TRUSTED)
840 goto trusted;
841 if (trust == X509_TRUST_REJECTED)
842 goto rejected;
843 }
844
845 /*
846 * If we are looking at a trusted certificate, and accept partial chains,
847 * the chain is PKIX trusted.
848 */
849 if (num_untrusted < num) {
850 if ((ctx->param->flags & X509_V_FLAG_PARTIAL_CHAIN) != 0)
851 goto trusted;
852 return X509_TRUST_UNTRUSTED;
853 }
854
855 if (num_untrusted == num
856 && (ctx->param->flags & X509_V_FLAG_PARTIAL_CHAIN) != 0) {
857 /*
858 * Last-resort call with no new trusted certificates, check the leaf
859 * for a direct trust store match.
860 */
861 i = 0;
862 x = sk_X509_value(ctx->chain, i);
863 res = lookup_cert_match(&mx, ctx, x);
864 if (res < 0)
865 return res;
866 if (mx == NULL)
867 return X509_TRUST_UNTRUSTED;
868
869 /*
870 * Check explicit auxiliary trust/reject settings. If none are set,
871 * we'll accept X509_TRUST_UNTRUSTED when not self-signed.
872 */
873 trust = X509_check_trust(mx, ctx->param->trust, 0);
874 if (trust == X509_TRUST_REJECTED) {
875 X509_free(mx);
876 goto rejected;
877 }
878
879 /* Replace leaf with trusted match */
880 (void)sk_X509_set(ctx->chain, 0, mx);
881 X509_free(x);
882 ctx->num_untrusted = 0;
883 goto trusted;
884 }
885
886 /*
887 * If no trusted certs in chain at all return untrusted and allow
888 * standard (no issuer cert) etc errors to be indicated.
889 */
890 return X509_TRUST_UNTRUSTED;
891
892 rejected:
893 return verify_cb_cert(ctx, x, i, X509_V_ERR_CERT_REJECTED) == 0
894 ? X509_TRUST_REJECTED : X509_TRUST_UNTRUSTED;
895
896 trusted:
897 if (!DANETLS_ENABLED(dane))
898 return X509_TRUST_TRUSTED;
899 if (dane->pdpth < 0)
900 dane->pdpth = num_untrusted;
901 /* With DANE, PKIX alone is not trusted until we have both */
902 if (dane->mdpth >= 0)
903 return X509_TRUST_TRUSTED;
904 return X509_TRUST_UNTRUSTED;
905 }
906
907 /* Sadly, returns 0 also on internal error. */
check_revocation(X509_STORE_CTX * ctx)908 static int check_revocation(X509_STORE_CTX *ctx)
909 {
910 int i = 0, last = 0, ok = 0;
911
912 if ((ctx->param->flags & X509_V_FLAG_CRL_CHECK) == 0)
913 return 1;
914 if ((ctx->param->flags & X509_V_FLAG_CRL_CHECK_ALL) != 0) {
915 last = sk_X509_num(ctx->chain) - 1;
916 } else {
917 /* If checking CRL paths this isn't the EE certificate */
918 if (ctx->parent)
919 return 1;
920 last = 0;
921 }
922 for (i = 0; i <= last; i++) {
923 ctx->error_depth = i;
924 ok = check_cert(ctx);
925 if (!ok)
926 return ok;
927 }
928 return 1;
929 }
930
931 /* Sadly, returns 0 also on internal error. */
check_cert(X509_STORE_CTX * ctx)932 static int check_cert(X509_STORE_CTX *ctx)
933 {
934 X509_CRL *crl = NULL, *dcrl = NULL;
935 int ok = 0;
936 int cnum = ctx->error_depth;
937 X509 *x = sk_X509_value(ctx->chain, cnum);
938
939 ctx->current_cert = x;
940 ctx->current_issuer = NULL;
941 ctx->current_crl_score = 0;
942 ctx->current_reasons = 0;
943
944 if ((x->ex_flags & EXFLAG_PROXY) != 0)
945 return 1;
946
947 while (ctx->current_reasons != CRLDP_ALL_REASONS) {
948 unsigned int last_reasons = ctx->current_reasons;
949
950 /* Try to retrieve relevant CRL */
951 if (ctx->get_crl != NULL)
952 ok = ctx->get_crl(ctx, &crl, x);
953 else
954 ok = get_crl_delta(ctx, &crl, &dcrl, x);
955 /* If error looking up CRL, nothing we can do except notify callback */
956 if (!ok) {
957 ok = verify_cb_crl(ctx, X509_V_ERR_UNABLE_TO_GET_CRL);
958 goto done;
959 }
960 ctx->current_crl = crl;
961 ok = ctx->check_crl(ctx, crl);
962 if (!ok)
963 goto done;
964
965 if (dcrl != NULL) {
966 ok = ctx->check_crl(ctx, dcrl);
967 if (!ok)
968 goto done;
969 ok = ctx->cert_crl(ctx, dcrl, x);
970 if (!ok)
971 goto done;
972 } else {
973 ok = 1;
974 }
975
976 /* Don't look in full CRL if delta reason is removefromCRL */
977 if (ok != 2) {
978 ok = ctx->cert_crl(ctx, crl, x);
979 if (!ok)
980 goto done;
981 }
982
983 X509_CRL_free(crl);
984 X509_CRL_free(dcrl);
985 crl = NULL;
986 dcrl = NULL;
987 /*
988 * If reasons not updated we won't get anywhere by another iteration,
989 * so exit loop.
990 */
991 if (last_reasons == ctx->current_reasons) {
992 ok = verify_cb_crl(ctx, X509_V_ERR_UNABLE_TO_GET_CRL);
993 goto done;
994 }
995 }
996 done:
997 X509_CRL_free(crl);
998 X509_CRL_free(dcrl);
999
1000 ctx->current_crl = NULL;
1001 return ok;
1002 }
1003
1004 /* Check CRL times against values in X509_STORE_CTX */
check_crl_time(X509_STORE_CTX * ctx,X509_CRL * crl,int notify)1005 static int check_crl_time(X509_STORE_CTX *ctx, X509_CRL *crl, int notify)
1006 {
1007 time_t *ptime;
1008 int i;
1009
1010 if ((ctx->param->flags & X509_V_FLAG_USE_CHECK_TIME) != 0)
1011 ptime = &ctx->param->check_time;
1012 else if ((ctx->param->flags & X509_V_FLAG_NO_CHECK_TIME) != 0)
1013 return 1;
1014 else
1015 ptime = NULL;
1016 if (notify)
1017 ctx->current_crl = crl;
1018
1019 i = X509_cmp_time(X509_CRL_get0_lastUpdate(crl), ptime);
1020 if (i == 0) {
1021 if (!notify)
1022 return 0;
1023 if (!verify_cb_crl(ctx, X509_V_ERR_ERROR_IN_CRL_LAST_UPDATE_FIELD))
1024 return 0;
1025 }
1026
1027 if (i > 0) {
1028 if (!notify)
1029 return 0;
1030 if (!verify_cb_crl(ctx, X509_V_ERR_CRL_NOT_YET_VALID))
1031 return 0;
1032 }
1033
1034 if (X509_CRL_get0_nextUpdate(crl)) {
1035 i = X509_cmp_time(X509_CRL_get0_nextUpdate(crl), ptime);
1036
1037 if (i == 0) {
1038 if (!notify)
1039 return 0;
1040 if (!verify_cb_crl(ctx, X509_V_ERR_ERROR_IN_CRL_NEXT_UPDATE_FIELD))
1041 return 0;
1042 }
1043 /* Ignore expiration of base CRL is delta is valid */
1044 if (i < 0 && (ctx->current_crl_score & CRL_SCORE_TIME_DELTA) == 0) {
1045 if (!notify || !verify_cb_crl(ctx, X509_V_ERR_CRL_HAS_EXPIRED))
1046 return 0;
1047 }
1048 }
1049
1050 if (notify)
1051 ctx->current_crl = NULL;
1052
1053 return 1;
1054 }
1055
get_crl_sk(X509_STORE_CTX * ctx,X509_CRL ** pcrl,X509_CRL ** pdcrl,X509 ** pissuer,int * pscore,unsigned int * preasons,STACK_OF (X509_CRL)* crls)1056 static int get_crl_sk(X509_STORE_CTX *ctx, X509_CRL **pcrl, X509_CRL **pdcrl,
1057 X509 **pissuer, int *pscore, unsigned int *preasons,
1058 STACK_OF(X509_CRL) *crls)
1059 {
1060 int i, crl_score, best_score = *pscore;
1061 unsigned int reasons, best_reasons = 0;
1062 X509 *x = ctx->current_cert;
1063 X509_CRL *crl, *best_crl = NULL;
1064 X509 *crl_issuer = NULL, *best_crl_issuer = NULL;
1065
1066 for (i = 0; i < sk_X509_CRL_num(crls); i++) {
1067 crl = sk_X509_CRL_value(crls, i);
1068 reasons = *preasons;
1069 crl_score = get_crl_score(ctx, &crl_issuer, &reasons, crl, x);
1070 if (crl_score < best_score || crl_score == 0)
1071 continue;
1072 /* If current CRL is equivalent use it if it is newer */
1073 if (crl_score == best_score && best_crl != NULL) {
1074 int day, sec;
1075
1076 if (ASN1_TIME_diff(&day, &sec, X509_CRL_get0_lastUpdate(best_crl),
1077 X509_CRL_get0_lastUpdate(crl)) == 0)
1078 continue;
1079 /*
1080 * ASN1_TIME_diff never returns inconsistent signs for |day|
1081 * and |sec|.
1082 */
1083 if (day <= 0 && sec <= 0)
1084 continue;
1085 }
1086 best_crl = crl;
1087 best_crl_issuer = crl_issuer;
1088 best_score = crl_score;
1089 best_reasons = reasons;
1090 }
1091
1092 if (best_crl != NULL) {
1093 X509_CRL_free(*pcrl);
1094 *pcrl = best_crl;
1095 *pissuer = best_crl_issuer;
1096 *pscore = best_score;
1097 *preasons = best_reasons;
1098 X509_CRL_up_ref(best_crl);
1099 X509_CRL_free(*pdcrl);
1100 *pdcrl = NULL;
1101 get_delta_sk(ctx, pdcrl, pscore, best_crl, crls);
1102 }
1103
1104 if (best_score >= CRL_SCORE_VALID)
1105 return 1;
1106
1107 return 0;
1108 }
1109
1110 /*
1111 * Compare two CRL extensions for delta checking purposes. They should be
1112 * both present or both absent. If both present all fields must be identical.
1113 */
crl_extension_match(X509_CRL * a,X509_CRL * b,int nid)1114 static int crl_extension_match(X509_CRL *a, X509_CRL *b, int nid)
1115 {
1116 ASN1_OCTET_STRING *exta = NULL, *extb = NULL;
1117 int i = X509_CRL_get_ext_by_NID(a, nid, -1);
1118
1119 if (i >= 0) {
1120 /* Can't have multiple occurrences */
1121 if (X509_CRL_get_ext_by_NID(a, nid, i) != -1)
1122 return 0;
1123 exta = X509_EXTENSION_get_data(X509_CRL_get_ext(a, i));
1124 }
1125
1126 i = X509_CRL_get_ext_by_NID(b, nid, -1);
1127 if (i >= 0) {
1128 if (X509_CRL_get_ext_by_NID(b, nid, i) != -1)
1129 return 0;
1130 extb = X509_EXTENSION_get_data(X509_CRL_get_ext(b, i));
1131 }
1132
1133 if (exta == NULL && extb == NULL)
1134 return 1;
1135
1136 if (exta == NULL || extb == NULL)
1137 return 0;
1138
1139 return ASN1_OCTET_STRING_cmp(exta, extb) == 0;
1140 }
1141
1142 /* See if a base and delta are compatible */
check_delta_base(X509_CRL * delta,X509_CRL * base)1143 static int check_delta_base(X509_CRL *delta, X509_CRL *base)
1144 {
1145 /* Delta CRL must be a delta */
1146 if (delta->base_crl_number == NULL)
1147 return 0;
1148 /* Base must have a CRL number */
1149 if (base->crl_number == NULL)
1150 return 0;
1151 /* Issuer names must match */
1152 if (X509_NAME_cmp(X509_CRL_get_issuer(base),
1153 X509_CRL_get_issuer(delta)) != 0)
1154 return 0;
1155 /* AKID and IDP must match */
1156 if (!crl_extension_match(delta, base, NID_authority_key_identifier))
1157 return 0;
1158 if (!crl_extension_match(delta, base, NID_issuing_distribution_point))
1159 return 0;
1160 /* Delta CRL base number must not exceed Full CRL number. */
1161 if (ASN1_INTEGER_cmp(delta->base_crl_number, base->crl_number) > 0)
1162 return 0;
1163 /* Delta CRL number must exceed full CRL number */
1164 return ASN1_INTEGER_cmp(delta->crl_number, base->crl_number) > 0;
1165 }
1166
1167 /*
1168 * For a given base CRL find a delta... maybe extend to delta scoring or
1169 * retrieve a chain of deltas...
1170 */
get_delta_sk(X509_STORE_CTX * ctx,X509_CRL ** dcrl,int * pscore,X509_CRL * base,STACK_OF (X509_CRL)* crls)1171 static void get_delta_sk(X509_STORE_CTX *ctx, X509_CRL **dcrl, int *pscore,
1172 X509_CRL *base, STACK_OF(X509_CRL) *crls)
1173 {
1174 X509_CRL *delta;
1175 int i;
1176
1177 if ((ctx->param->flags & X509_V_FLAG_USE_DELTAS) == 0)
1178 return;
1179 if (((ctx->current_cert->ex_flags | base->flags) & EXFLAG_FRESHEST) == 0)
1180 return;
1181 for (i = 0; i < sk_X509_CRL_num(crls); i++) {
1182 delta = sk_X509_CRL_value(crls, i);
1183 if (check_delta_base(delta, base)) {
1184 if (check_crl_time(ctx, delta, 0))
1185 *pscore |= CRL_SCORE_TIME_DELTA;
1186 X509_CRL_up_ref(delta);
1187 *dcrl = delta;
1188 return;
1189 }
1190 }
1191 *dcrl = NULL;
1192 }
1193
1194 /*
1195 * For a given CRL return how suitable it is for the supplied certificate
1196 * 'x'. The return value is a mask of several criteria. If the issuer is not
1197 * the certificate issuer this is returned in *pissuer. The reasons mask is
1198 * also used to determine if the CRL is suitable: if no new reasons the CRL
1199 * is rejected, otherwise reasons is updated.
1200 */
get_crl_score(X509_STORE_CTX * ctx,X509 ** pissuer,unsigned int * preasons,X509_CRL * crl,X509 * x)1201 static int get_crl_score(X509_STORE_CTX *ctx, X509 **pissuer,
1202 unsigned int *preasons, X509_CRL *crl, X509 *x)
1203 {
1204 int crl_score = 0;
1205 unsigned int tmp_reasons = *preasons, crl_reasons;
1206
1207 /* First see if we can reject CRL straight away */
1208
1209 /* Invalid IDP cannot be processed */
1210 if ((crl->idp_flags & IDP_INVALID) != 0)
1211 return 0;
1212 /* Reason codes or indirect CRLs need extended CRL support */
1213 if ((ctx->param->flags & X509_V_FLAG_EXTENDED_CRL_SUPPORT) == 0) {
1214 if (crl->idp_flags & (IDP_INDIRECT | IDP_REASONS))
1215 return 0;
1216 } else if ((crl->idp_flags & IDP_REASONS) != 0) {
1217 /* If no new reasons reject */
1218 if ((crl->idp_reasons & ~tmp_reasons) == 0)
1219 return 0;
1220 }
1221 /* Don't process deltas at this stage */
1222 else if (crl->base_crl_number != NULL)
1223 return 0;
1224 /* If issuer name doesn't match certificate need indirect CRL */
1225 if (X509_NAME_cmp(X509_get_issuer_name(x), X509_CRL_get_issuer(crl)) != 0) {
1226 if ((crl->idp_flags & IDP_INDIRECT) == 0)
1227 return 0;
1228 } else {
1229 crl_score |= CRL_SCORE_ISSUER_NAME;
1230 }
1231
1232 if ((crl->flags & EXFLAG_CRITICAL) == 0)
1233 crl_score |= CRL_SCORE_NOCRITICAL;
1234
1235 /* Check expiration */
1236 if (check_crl_time(ctx, crl, 0))
1237 crl_score |= CRL_SCORE_TIME;
1238
1239 /* Check authority key ID and locate certificate issuer */
1240 crl_akid_check(ctx, crl, pissuer, &crl_score);
1241
1242 /* If we can't locate certificate issuer at this point forget it */
1243 if ((crl_score & CRL_SCORE_AKID) == 0)
1244 return 0;
1245
1246 /* Check cert for matching CRL distribution points */
1247 if (crl_crldp_check(x, crl, crl_score, &crl_reasons)) {
1248 /* If no new reasons reject */
1249 if ((crl_reasons & ~tmp_reasons) == 0)
1250 return 0;
1251 tmp_reasons |= crl_reasons;
1252 crl_score |= CRL_SCORE_SCOPE;
1253 }
1254
1255 *preasons = tmp_reasons;
1256
1257 return crl_score;
1258
1259 }
1260
crl_akid_check(X509_STORE_CTX * ctx,X509_CRL * crl,X509 ** pissuer,int * pcrl_score)1261 static void crl_akid_check(X509_STORE_CTX *ctx, X509_CRL *crl,
1262 X509 **pissuer, int *pcrl_score)
1263 {
1264 X509 *crl_issuer = NULL;
1265 const X509_NAME *cnm = X509_CRL_get_issuer(crl);
1266 int cidx = ctx->error_depth;
1267 int i;
1268
1269 if (cidx != sk_X509_num(ctx->chain) - 1)
1270 cidx++;
1271
1272 crl_issuer = sk_X509_value(ctx->chain, cidx);
1273
1274 if (X509_check_akid(crl_issuer, crl->akid) == X509_V_OK) {
1275 if (*pcrl_score & CRL_SCORE_ISSUER_NAME) {
1276 *pcrl_score |= CRL_SCORE_AKID | CRL_SCORE_ISSUER_CERT;
1277 *pissuer = crl_issuer;
1278 return;
1279 }
1280 }
1281
1282 for (cidx++; cidx < sk_X509_num(ctx->chain); cidx++) {
1283 crl_issuer = sk_X509_value(ctx->chain, cidx);
1284 if (X509_NAME_cmp(X509_get_subject_name(crl_issuer), cnm))
1285 continue;
1286 if (X509_check_akid(crl_issuer, crl->akid) == X509_V_OK) {
1287 *pcrl_score |= CRL_SCORE_AKID | CRL_SCORE_SAME_PATH;
1288 *pissuer = crl_issuer;
1289 return;
1290 }
1291 }
1292
1293 /* Anything else needs extended CRL support */
1294 if ((ctx->param->flags & X509_V_FLAG_EXTENDED_CRL_SUPPORT) == 0)
1295 return;
1296
1297 /*
1298 * Otherwise the CRL issuer is not on the path. Look for it in the set of
1299 * untrusted certificates.
1300 */
1301 for (i = 0; i < sk_X509_num(ctx->untrusted); i++) {
1302 crl_issuer = sk_X509_value(ctx->untrusted, i);
1303 if (X509_NAME_cmp(X509_get_subject_name(crl_issuer), cnm) != 0)
1304 continue;
1305 if (X509_check_akid(crl_issuer, crl->akid) == X509_V_OK) {
1306 *pissuer = crl_issuer;
1307 *pcrl_score |= CRL_SCORE_AKID;
1308 return;
1309 }
1310 }
1311 }
1312
1313 /*
1314 * Check the path of a CRL issuer certificate. This creates a new
1315 * X509_STORE_CTX and populates it with most of the parameters from the
1316 * parent. This could be optimised somewhat since a lot of path checking will
1317 * be duplicated by the parent, but this will rarely be used in practice.
1318 */
check_crl_path(X509_STORE_CTX * ctx,X509 * x)1319 static int check_crl_path(X509_STORE_CTX *ctx, X509 *x)
1320 {
1321 X509_STORE_CTX crl_ctx = {0};
1322 int ret;
1323
1324 /* Don't allow recursive CRL path validation */
1325 if (ctx->parent != NULL)
1326 return 0;
1327 if (!X509_STORE_CTX_init(&crl_ctx, ctx->store, x, ctx->untrusted))
1328 return -1;
1329
1330 crl_ctx.crls = ctx->crls;
1331 /* Copy verify params across */
1332 X509_STORE_CTX_set0_param(&crl_ctx, ctx->param);
1333
1334 crl_ctx.parent = ctx;
1335 crl_ctx.verify_cb = ctx->verify_cb;
1336
1337 /* Verify CRL issuer */
1338 ret = X509_verify_cert(&crl_ctx);
1339 if (ret <= 0)
1340 goto err;
1341
1342 /* Check chain is acceptable */
1343 ret = check_crl_chain(ctx, ctx->chain, crl_ctx.chain);
1344 err:
1345 X509_STORE_CTX_cleanup(&crl_ctx);
1346 return ret;
1347 }
1348
1349 /*
1350 * RFC3280 says nothing about the relationship between CRL path and
1351 * certificate path, which could lead to situations where a certificate could
1352 * be revoked or validated by a CA not authorized to do so. RFC5280 is more
1353 * strict and states that the two paths must end in the same trust anchor,
1354 * though some discussions remain... until this is resolved we use the
1355 * RFC5280 version
1356 */
check_crl_chain(X509_STORE_CTX * ctx,STACK_OF (X509)* cert_path,STACK_OF (X509)* crl_path)1357 static int check_crl_chain(X509_STORE_CTX *ctx,
1358 STACK_OF(X509) *cert_path,
1359 STACK_OF(X509) *crl_path)
1360 {
1361 X509 *cert_ta = sk_X509_value(cert_path, sk_X509_num(cert_path) - 1);
1362 X509 *crl_ta = sk_X509_value(crl_path, sk_X509_num(crl_path) - 1);
1363
1364 return X509_cmp(cert_ta, crl_ta) == 0;
1365 }
1366
1367 /*-
1368 * Check for match between two dist point names: three separate cases.
1369 * 1. Both are relative names and compare X509_NAME types.
1370 * 2. One full, one relative. Compare X509_NAME to GENERAL_NAMES.
1371 * 3. Both are full names and compare two GENERAL_NAMES.
1372 * 4. One is NULL: automatic match.
1373 */
idp_check_dp(DIST_POINT_NAME * a,DIST_POINT_NAME * b)1374 static int idp_check_dp(DIST_POINT_NAME *a, DIST_POINT_NAME *b)
1375 {
1376 X509_NAME *nm = NULL;
1377 GENERAL_NAMES *gens = NULL;
1378 GENERAL_NAME *gena, *genb;
1379 int i, j;
1380
1381 if (a == NULL || b == NULL)
1382 return 1;
1383 if (a->type == 1) {
1384 if (a->dpname == NULL)
1385 return 0;
1386 /* Case 1: two X509_NAME */
1387 if (b->type == 1) {
1388 if (b->dpname == NULL)
1389 return 0;
1390 return X509_NAME_cmp(a->dpname, b->dpname) == 0;
1391 }
1392 /* Case 2: set name and GENERAL_NAMES appropriately */
1393 nm = a->dpname;
1394 gens = b->name.fullname;
1395 } else if (b->type == 1) {
1396 if (b->dpname == NULL)
1397 return 0;
1398 /* Case 2: set name and GENERAL_NAMES appropriately */
1399 gens = a->name.fullname;
1400 nm = b->dpname;
1401 }
1402
1403 /* Handle case 2 with one GENERAL_NAMES and one X509_NAME */
1404 if (nm != NULL) {
1405 for (i = 0; i < sk_GENERAL_NAME_num(gens); i++) {
1406 gena = sk_GENERAL_NAME_value(gens, i);
1407 if (gena->type != GEN_DIRNAME)
1408 continue;
1409 if (X509_NAME_cmp(nm, gena->d.directoryName) == 0)
1410 return 1;
1411 }
1412 return 0;
1413 }
1414
1415 /* Else case 3: two GENERAL_NAMES */
1416
1417 for (i = 0; i < sk_GENERAL_NAME_num(a->name.fullname); i++) {
1418 gena = sk_GENERAL_NAME_value(a->name.fullname, i);
1419 for (j = 0; j < sk_GENERAL_NAME_num(b->name.fullname); j++) {
1420 genb = sk_GENERAL_NAME_value(b->name.fullname, j);
1421 if (GENERAL_NAME_cmp(gena, genb) == 0)
1422 return 1;
1423 }
1424 }
1425
1426 return 0;
1427
1428 }
1429
crldp_check_crlissuer(DIST_POINT * dp,X509_CRL * crl,int crl_score)1430 static int crldp_check_crlissuer(DIST_POINT *dp, X509_CRL *crl, int crl_score)
1431 {
1432 int i;
1433 const X509_NAME *nm = X509_CRL_get_issuer(crl);
1434
1435 /* If no CRLissuer return is successful iff don't need a match */
1436 if (dp->CRLissuer == NULL)
1437 return (crl_score & CRL_SCORE_ISSUER_NAME) != 0;
1438 for (i = 0; i < sk_GENERAL_NAME_num(dp->CRLissuer); i++) {
1439 GENERAL_NAME *gen = sk_GENERAL_NAME_value(dp->CRLissuer, i);
1440
1441 if (gen->type != GEN_DIRNAME)
1442 continue;
1443 if (X509_NAME_cmp(gen->d.directoryName, nm) == 0)
1444 return 1;
1445 }
1446 return 0;
1447 }
1448
1449 /* Check CRLDP and IDP */
crl_crldp_check(X509 * x,X509_CRL * crl,int crl_score,unsigned int * preasons)1450 static int crl_crldp_check(X509 *x, X509_CRL *crl, int crl_score,
1451 unsigned int *preasons)
1452 {
1453 int i;
1454
1455 if ((crl->idp_flags & IDP_ONLYATTR) != 0)
1456 return 0;
1457 if ((x->ex_flags & EXFLAG_CA) != 0) {
1458 if ((crl->idp_flags & IDP_ONLYUSER) != 0)
1459 return 0;
1460 } else {
1461 if ((crl->idp_flags & IDP_ONLYCA) != 0)
1462 return 0;
1463 }
1464 *preasons = crl->idp_reasons;
1465 for (i = 0; i < sk_DIST_POINT_num(x->crldp); i++) {
1466 DIST_POINT *dp = sk_DIST_POINT_value(x->crldp, i);
1467
1468 if (crldp_check_crlissuer(dp, crl, crl_score)) {
1469 if (crl->idp == NULL
1470 || idp_check_dp(dp->distpoint, crl->idp->distpoint)) {
1471 *preasons &= dp->dp_reasons;
1472 return 1;
1473 }
1474 }
1475 }
1476 return (crl->idp == NULL || crl->idp->distpoint == NULL)
1477 && (crl_score & CRL_SCORE_ISSUER_NAME) != 0;
1478 }
1479
1480 /*
1481 * Retrieve CRL corresponding to current certificate. If deltas enabled try
1482 * to find a delta CRL too
1483 */
get_crl_delta(X509_STORE_CTX * ctx,X509_CRL ** pcrl,X509_CRL ** pdcrl,X509 * x)1484 static int get_crl_delta(X509_STORE_CTX *ctx,
1485 X509_CRL **pcrl, X509_CRL **pdcrl, X509 *x)
1486 {
1487 int ok;
1488 X509 *issuer = NULL;
1489 int crl_score = 0;
1490 unsigned int reasons;
1491 X509_CRL *crl = NULL, *dcrl = NULL;
1492 STACK_OF(X509_CRL) *skcrl;
1493 const X509_NAME *nm = X509_get_issuer_name(x);
1494
1495 reasons = ctx->current_reasons;
1496 ok = get_crl_sk(ctx, &crl, &dcrl,
1497 &issuer, &crl_score, &reasons, ctx->crls);
1498 if (ok)
1499 goto done;
1500
1501 /* Lookup CRLs from store */
1502 skcrl = ctx->lookup_crls(ctx, nm);
1503
1504 /* If no CRLs found and a near match from get_crl_sk use that */
1505 if (skcrl == NULL && crl != NULL)
1506 goto done;
1507
1508 get_crl_sk(ctx, &crl, &dcrl, &issuer, &crl_score, &reasons, skcrl);
1509
1510 sk_X509_CRL_pop_free(skcrl, X509_CRL_free);
1511
1512 done:
1513 /* If we got any kind of CRL use it and return success */
1514 if (crl != NULL) {
1515 ctx->current_issuer = issuer;
1516 ctx->current_crl_score = crl_score;
1517 ctx->current_reasons = reasons;
1518 *pcrl = crl;
1519 *pdcrl = dcrl;
1520 return 1;
1521 }
1522 return 0;
1523 }
1524
1525 /* Check CRL validity */
check_crl(X509_STORE_CTX * ctx,X509_CRL * crl)1526 static int check_crl(X509_STORE_CTX *ctx, X509_CRL *crl)
1527 {
1528 X509 *issuer = NULL;
1529 EVP_PKEY *ikey = NULL;
1530 int cnum = ctx->error_depth;
1531 int chnum = sk_X509_num(ctx->chain) - 1;
1532
1533 /* If we have an alternative CRL issuer cert use that */
1534 if (ctx->current_issuer != NULL) {
1535 issuer = ctx->current_issuer;
1536 /*
1537 * Else find CRL issuer: if not last certificate then issuer is next
1538 * certificate in chain.
1539 */
1540 } else if (cnum < chnum) {
1541 issuer = sk_X509_value(ctx->chain, cnum + 1);
1542 } else {
1543 issuer = sk_X509_value(ctx->chain, chnum);
1544 /* If not self-issued, can't check signature */
1545 if (!ctx->check_issued(ctx, issuer, issuer) &&
1546 !verify_cb_crl(ctx, X509_V_ERR_UNABLE_TO_GET_CRL_ISSUER))
1547 return 0;
1548 }
1549
1550 if (issuer == NULL)
1551 return 1;
1552
1553 /*
1554 * Skip most tests for deltas because they have already been done
1555 */
1556 if (crl->base_crl_number == NULL) {
1557 /* Check for cRLSign bit if keyUsage present */
1558 if ((issuer->ex_flags & EXFLAG_KUSAGE) != 0 &&
1559 (issuer->ex_kusage & KU_CRL_SIGN) == 0 &&
1560 !verify_cb_crl(ctx, X509_V_ERR_KEYUSAGE_NO_CRL_SIGN))
1561 return 0;
1562
1563 if ((ctx->current_crl_score & CRL_SCORE_SCOPE) == 0 &&
1564 !verify_cb_crl(ctx, X509_V_ERR_DIFFERENT_CRL_SCOPE))
1565 return 0;
1566
1567 if ((ctx->current_crl_score & CRL_SCORE_SAME_PATH) == 0 &&
1568 check_crl_path(ctx, ctx->current_issuer) <= 0 &&
1569 !verify_cb_crl(ctx, X509_V_ERR_CRL_PATH_VALIDATION_ERROR))
1570 return 0;
1571
1572 if ((crl->idp_flags & IDP_INVALID) != 0 &&
1573 !verify_cb_crl(ctx, X509_V_ERR_INVALID_EXTENSION))
1574 return 0;
1575 }
1576
1577 if ((ctx->current_crl_score & CRL_SCORE_TIME) == 0 &&
1578 !check_crl_time(ctx, crl, 1))
1579 return 0;
1580
1581 /* Attempt to get issuer certificate public key */
1582 ikey = X509_get0_pubkey(issuer);
1583 if (ikey == NULL &&
1584 !verify_cb_crl(ctx, X509_V_ERR_UNABLE_TO_DECODE_ISSUER_PUBLIC_KEY))
1585 return 0;
1586
1587 if (ikey != NULL) {
1588 int rv = X509_CRL_check_suiteb(crl, ikey, ctx->param->flags);
1589
1590 if (rv != X509_V_OK && !verify_cb_crl(ctx, rv))
1591 return 0;
1592 /* Verify CRL signature */
1593 if (X509_CRL_verify(crl, ikey) <= 0 &&
1594 !verify_cb_crl(ctx, X509_V_ERR_CRL_SIGNATURE_FAILURE))
1595 return 0;
1596 }
1597 return 1;
1598 }
1599
1600 /* Check certificate against CRL */
cert_crl(X509_STORE_CTX * ctx,X509_CRL * crl,X509 * x)1601 static int cert_crl(X509_STORE_CTX *ctx, X509_CRL *crl, X509 *x)
1602 {
1603 X509_REVOKED *rev;
1604
1605 /*
1606 * The rules changed for this... previously if a CRL contained unhandled
1607 * critical extensions it could still be used to indicate a certificate
1608 * was revoked. This has since been changed since critical extensions can
1609 * change the meaning of CRL entries.
1610 */
1611 if ((ctx->param->flags & X509_V_FLAG_IGNORE_CRITICAL) == 0
1612 && (crl->flags & EXFLAG_CRITICAL) != 0 &&
1613 !verify_cb_crl(ctx, X509_V_ERR_UNHANDLED_CRITICAL_CRL_EXTENSION))
1614 return 0;
1615 /*
1616 * Look for serial number of certificate in CRL. If found, make sure
1617 * reason is not removeFromCRL.
1618 */
1619 if (X509_CRL_get0_by_cert(crl, &rev, x)) {
1620 if (rev->reason == CRL_REASON_REMOVE_FROM_CRL)
1621 return 2;
1622 if (!verify_cb_crl(ctx, X509_V_ERR_CERT_REVOKED))
1623 return 0;
1624 }
1625
1626 return 1;
1627 }
1628
check_policy(X509_STORE_CTX * ctx)1629 static int check_policy(X509_STORE_CTX *ctx)
1630 {
1631 int ret;
1632
1633 if (ctx->parent)
1634 return 1;
1635 /*
1636 * With DANE, the trust anchor might be a bare public key, not a
1637 * certificate! In that case our chain does not have the trust anchor
1638 * certificate as a top-most element. This comports well with RFC5280
1639 * chain verification, since there too, the trust anchor is not part of the
1640 * chain to be verified. In particular, X509_policy_check() does not look
1641 * at the TA cert, but assumes that it is present as the top-most chain
1642 * element. We therefore temporarily push a NULL cert onto the chain if it
1643 * was verified via a bare public key, and pop it off right after the
1644 * X509_policy_check() call.
1645 */
1646 if (ctx->bare_ta_signed && !sk_X509_push(ctx->chain, NULL))
1647 goto memerr;
1648 ret = X509_policy_check(&ctx->tree, &ctx->explicit_policy, ctx->chain,
1649 ctx->param->policies, ctx->param->flags);
1650 if (ctx->bare_ta_signed)
1651 (void)sk_X509_pop(ctx->chain);
1652
1653 if (ret == X509_PCY_TREE_INTERNAL)
1654 goto memerr;
1655 /* Invalid or inconsistent extensions */
1656 if (ret == X509_PCY_TREE_INVALID) {
1657 int i, cbcalled = 0;
1658
1659 /* Locate certificates with bad extensions and notify callback. */
1660 for (i = 0; i < sk_X509_num(ctx->chain); i++) {
1661 X509 *x = sk_X509_value(ctx->chain, i);
1662
1663 if ((x->ex_flags & EXFLAG_INVALID_POLICY) != 0)
1664 cbcalled = 1;
1665 CB_FAIL_IF((x->ex_flags & EXFLAG_INVALID_POLICY) != 0,
1666 ctx, x, i, X509_V_ERR_INVALID_POLICY_EXTENSION);
1667 }
1668 if (!cbcalled) {
1669 /* Should not be able to get here */
1670 ERR_raise(ERR_LIB_X509, ERR_R_INTERNAL_ERROR);
1671 return 0;
1672 }
1673 /* The callback ignored the error so we return success */
1674 return 1;
1675 }
1676 if (ret == X509_PCY_TREE_FAILURE) {
1677 ctx->current_cert = NULL;
1678 ctx->error = X509_V_ERR_NO_EXPLICIT_POLICY;
1679 return ctx->verify_cb(0, ctx);
1680 }
1681 if (ret != X509_PCY_TREE_VALID) {
1682 ERR_raise(ERR_LIB_X509, ERR_R_INTERNAL_ERROR);
1683 return 0;
1684 }
1685
1686 if ((ctx->param->flags & X509_V_FLAG_NOTIFY_POLICY) != 0) {
1687 ctx->current_cert = NULL;
1688 /*
1689 * Verification errors need to be "sticky", a callback may have allowed
1690 * an SSL handshake to continue despite an error, and we must then
1691 * remain in an error state. Therefore, we MUST NOT clear earlier
1692 * verification errors by setting the error to X509_V_OK.
1693 */
1694 if (!ctx->verify_cb(2, ctx))
1695 return 0;
1696 }
1697
1698 return 1;
1699
1700 memerr:
1701 ERR_raise(ERR_LIB_X509, ERR_R_MALLOC_FAILURE);
1702 ctx->error = X509_V_ERR_OUT_OF_MEM;
1703 return -1;
1704 }
1705
1706 /*-
1707 * Check certificate validity times.
1708 * If depth >= 0, invoke verification callbacks on error, otherwise just return
1709 * the validation status.
1710 *
1711 * Return 1 on success, 0 otherwise.
1712 */
ossl_x509_check_cert_time(X509_STORE_CTX * ctx,X509 * x,int depth)1713 int ossl_x509_check_cert_time(X509_STORE_CTX *ctx, X509 *x, int depth)
1714 {
1715 time_t *ptime;
1716 int i;
1717
1718 if ((ctx->param->flags & X509_V_FLAG_USE_CHECK_TIME) != 0)
1719 ptime = &ctx->param->check_time;
1720 else if ((ctx->param->flags & X509_V_FLAG_NO_CHECK_TIME) != 0)
1721 return 1;
1722 else
1723 ptime = NULL;
1724
1725 i = X509_cmp_time(X509_get0_notBefore(x), ptime);
1726 if (i >= 0 && depth < 0)
1727 return 0;
1728 CB_FAIL_IF(i == 0, ctx, x, depth, X509_V_ERR_ERROR_IN_CERT_NOT_BEFORE_FIELD);
1729 CB_FAIL_IF(i > 0, ctx, x, depth, X509_V_ERR_CERT_NOT_YET_VALID);
1730
1731 i = X509_cmp_time(X509_get0_notAfter(x), ptime);
1732 if (i <= 0 && depth < 0)
1733 return 0;
1734 CB_FAIL_IF(i == 0, ctx, x, depth, X509_V_ERR_ERROR_IN_CERT_NOT_AFTER_FIELD);
1735 CB_FAIL_IF(i < 0, ctx, x, depth, X509_V_ERR_CERT_HAS_EXPIRED);
1736 return 1;
1737 }
1738
1739 /*
1740 * Verify the issuer signatures and cert times of ctx->chain.
1741 * Sadly, returns 0 also on internal error.
1742 */
internal_verify(X509_STORE_CTX * ctx)1743 static int internal_verify(X509_STORE_CTX *ctx)
1744 {
1745 int n = sk_X509_num(ctx->chain) - 1;
1746 X509 *xi = sk_X509_value(ctx->chain, n);
1747 X509 *xs = xi;
1748
1749 ctx->error_depth = n;
1750 if (ctx->bare_ta_signed) {
1751 /*
1752 * With DANE-verified bare public key TA signatures,
1753 * on the top certificate we check only the timestamps.
1754 * We report the issuer as NULL because all we have is a bare key.
1755 */
1756 xi = NULL;
1757 } else if (ossl_x509_likely_issued(xi, xi) != X509_V_OK
1758 /* exceptional case: last cert in the chain is not self-issued */
1759 && ((ctx->param->flags & X509_V_FLAG_PARTIAL_CHAIN) == 0)) {
1760 if (n > 0) {
1761 n--;
1762 ctx->error_depth = n;
1763 xs = sk_X509_value(ctx->chain, n);
1764 } else {
1765 CB_FAIL_IF(1, ctx, xi, 0,
1766 X509_V_ERR_UNABLE_TO_VERIFY_LEAF_SIGNATURE);
1767 }
1768 /*
1769 * The below code will certainly not do a
1770 * self-signature check on xi because it is not self-issued.
1771 */
1772 }
1773
1774 /*
1775 * Do not clear error (by ctx->error = X509_V_OK), it must be "sticky",
1776 * only the user's callback is allowed to reset errors (at its own peril).
1777 */
1778 while (n >= 0) {
1779 /*-
1780 * For each iteration of this loop:
1781 * n is the subject depth
1782 * xs is the subject cert, for which the signature is to be checked
1783 * xi is NULL for DANE-verified bare public key TA signatures
1784 * else the supposed issuer cert containing the public key to use
1785 * Initially xs == xi if the last cert in the chain is self-issued.
1786 */
1787 /*
1788 * Do signature check for self-signed certificates only if explicitly
1789 * asked for because it does not add any security and just wastes time.
1790 */
1791 if (xi != NULL
1792 && (xs != xi
1793 || ((ctx->param->flags & X509_V_FLAG_CHECK_SS_SIGNATURE) != 0
1794 && (xi->ex_flags & EXFLAG_SS) != 0))) {
1795 EVP_PKEY *pkey;
1796 /*
1797 * If the issuer's public key is not available or its key usage
1798 * does not support issuing the subject cert, report the issuer
1799 * cert and its depth (rather than n, the depth of the subject).
1800 */
1801 int issuer_depth = n + (xs == xi ? 0 : 1);
1802 /*
1803 * According to https://tools.ietf.org/html/rfc5280#section-6.1.4
1804 * step (n) we must check any given key usage extension in a CA cert
1805 * when preparing the verification of a certificate issued by it.
1806 * According to https://tools.ietf.org/html/rfc5280#section-4.2.1.3
1807 * we must not verify a certificate signature if the key usage of
1808 * the CA certificate that issued the certificate prohibits signing.
1809 * In case the 'issuing' certificate is the last in the chain and is
1810 * not a CA certificate but a 'self-issued' end-entity cert (i.e.,
1811 * xs == xi && !(xi->ex_flags & EXFLAG_CA)) RFC 5280 does not apply
1812 * (see https://tools.ietf.org/html/rfc6818#section-2) and thus
1813 * we are free to ignore any key usage restrictions on such certs.
1814 */
1815 int ret = xs == xi && (xi->ex_flags & EXFLAG_CA) == 0
1816 ? X509_V_OK : ossl_x509_signing_allowed(xi, xs);
1817
1818 CB_FAIL_IF(ret != X509_V_OK, ctx, xi, issuer_depth, ret);
1819 if ((pkey = X509_get0_pubkey(xi)) == NULL) {
1820 CB_FAIL_IF(1, ctx, xi, issuer_depth,
1821 X509_V_ERR_UNABLE_TO_DECODE_ISSUER_PUBLIC_KEY);
1822 } else {
1823 CB_FAIL_IF(X509_verify(xs, pkey) <= 0,
1824 ctx, xs, n, X509_V_ERR_CERT_SIGNATURE_FAILURE);
1825 }
1826 }
1827
1828 /* In addition to RFC 5280 requirements do also for trust anchor cert */
1829 /* Calls verify callback as needed */
1830 if (!ossl_x509_check_cert_time(ctx, xs, n))
1831 return 0;
1832
1833 /*
1834 * Signal success at this depth. However, the previous error (if any)
1835 * is retained.
1836 */
1837 ctx->current_issuer = xi;
1838 ctx->current_cert = xs;
1839 ctx->error_depth = n;
1840 if (!ctx->verify_cb(1, ctx))
1841 return 0;
1842
1843 if (--n >= 0) {
1844 xi = xs;
1845 xs = sk_X509_value(ctx->chain, n);
1846 }
1847 }
1848 return 1;
1849 }
1850
X509_cmp_current_time(const ASN1_TIME * ctm)1851 int X509_cmp_current_time(const ASN1_TIME *ctm)
1852 {
1853 return X509_cmp_time(ctm, NULL);
1854 }
1855
X509_cmp_time(const ASN1_TIME * ctm,time_t * cmp_time)1856 int X509_cmp_time(const ASN1_TIME *ctm, time_t *cmp_time)
1857 {
1858 static const size_t utctime_length = sizeof("YYMMDDHHMMSSZ") - 1;
1859 static const size_t generalizedtime_length = sizeof("YYYYMMDDHHMMSSZ") - 1;
1860 ASN1_TIME *asn1_cmp_time = NULL;
1861 int i, day, sec, ret = 0;
1862 #ifdef CHARSET_EBCDIC
1863 const char upper_z = 0x5A;
1864 #else
1865 const char upper_z = 'Z';
1866 #endif
1867
1868 /*-
1869 * Note that ASN.1 allows much more slack in the time format than RFC5280.
1870 * In RFC5280, the representation is fixed:
1871 * UTCTime: YYMMDDHHMMSSZ
1872 * GeneralizedTime: YYYYMMDDHHMMSSZ
1873 *
1874 * We do NOT currently enforce the following RFC 5280 requirement:
1875 * "CAs conforming to this profile MUST always encode certificate
1876 * validity dates through the year 2049 as UTCTime; certificate validity
1877 * dates in 2050 or later MUST be encoded as GeneralizedTime."
1878 */
1879 switch (ctm->type) {
1880 case V_ASN1_UTCTIME:
1881 if (ctm->length != (int)(utctime_length))
1882 return 0;
1883 break;
1884 case V_ASN1_GENERALIZEDTIME:
1885 if (ctm->length != (int)(generalizedtime_length))
1886 return 0;
1887 break;
1888 default:
1889 return 0;
1890 }
1891
1892 /**
1893 * Verify the format: the ASN.1 functions we use below allow a more
1894 * flexible format than what's mandated by RFC 5280.
1895 * Digit and date ranges will be verified in the conversion methods.
1896 */
1897 for (i = 0; i < ctm->length - 1; i++) {
1898 if (!ossl_ascii_isdigit(ctm->data[i]))
1899 return 0;
1900 }
1901 if (ctm->data[ctm->length - 1] != upper_z)
1902 return 0;
1903
1904 /*
1905 * There is ASN1_UTCTIME_cmp_time_t but no
1906 * ASN1_GENERALIZEDTIME_cmp_time_t or ASN1_TIME_cmp_time_t,
1907 * so we go through ASN.1
1908 */
1909 asn1_cmp_time = X509_time_adj(NULL, 0, cmp_time);
1910 if (asn1_cmp_time == NULL)
1911 goto err;
1912 if (ASN1_TIME_diff(&day, &sec, ctm, asn1_cmp_time) == 0)
1913 goto err;
1914
1915 /*
1916 * X509_cmp_time comparison is <=.
1917 * The return value 0 is reserved for errors.
1918 */
1919 ret = (day >= 0 && sec >= 0) ? -1 : 1;
1920
1921 err:
1922 ASN1_TIME_free(asn1_cmp_time);
1923 return ret;
1924 }
1925
1926 /*
1927 * Return 0 if time should not be checked or reference time is in range,
1928 * or else 1 if it is past the end, or -1 if it is before the start
1929 */
X509_cmp_timeframe(const X509_VERIFY_PARAM * vpm,const ASN1_TIME * start,const ASN1_TIME * end)1930 int X509_cmp_timeframe(const X509_VERIFY_PARAM *vpm,
1931 const ASN1_TIME *start, const ASN1_TIME *end)
1932 {
1933 time_t ref_time;
1934 time_t *time = NULL;
1935 unsigned long flags = vpm == NULL ? 0 : X509_VERIFY_PARAM_get_flags(vpm);
1936
1937 if ((flags & X509_V_FLAG_USE_CHECK_TIME) != 0) {
1938 ref_time = X509_VERIFY_PARAM_get_time(vpm);
1939 time = &ref_time;
1940 } else if ((flags & X509_V_FLAG_NO_CHECK_TIME) != 0) {
1941 return 0; /* this means ok */
1942 } /* else reference time is the current time */
1943
1944 if (end != NULL && X509_cmp_time(end, time) < 0)
1945 return 1;
1946 if (start != NULL && X509_cmp_time(start, time) > 0)
1947 return -1;
1948 return 0;
1949 }
1950
X509_gmtime_adj(ASN1_TIME * s,long adj)1951 ASN1_TIME *X509_gmtime_adj(ASN1_TIME *s, long adj)
1952 {
1953 return X509_time_adj(s, adj, NULL);
1954 }
1955
X509_time_adj(ASN1_TIME * s,long offset_sec,time_t * in_tm)1956 ASN1_TIME *X509_time_adj(ASN1_TIME *s, long offset_sec, time_t *in_tm)
1957 {
1958 return X509_time_adj_ex(s, 0, offset_sec, in_tm);
1959 }
1960
X509_time_adj_ex(ASN1_TIME * s,int offset_day,long offset_sec,time_t * in_tm)1961 ASN1_TIME *X509_time_adj_ex(ASN1_TIME *s,
1962 int offset_day, long offset_sec, time_t *in_tm)
1963 {
1964 time_t t;
1965
1966 if (in_tm)
1967 t = *in_tm;
1968 else
1969 time(&t);
1970
1971 if (s != NULL && (s->flags & ASN1_STRING_FLAG_MSTRING) == 0) {
1972 if (s->type == V_ASN1_UTCTIME)
1973 return ASN1_UTCTIME_adj(s, t, offset_day, offset_sec);
1974 if (s->type == V_ASN1_GENERALIZEDTIME)
1975 return ASN1_GENERALIZEDTIME_adj(s, t, offset_day, offset_sec);
1976 }
1977 return ASN1_TIME_adj(s, t, offset_day, offset_sec);
1978 }
1979
1980 /* Copy any missing public key parameters up the chain towards pkey */
X509_get_pubkey_parameters(EVP_PKEY * pkey,STACK_OF (X509)* chain)1981 int X509_get_pubkey_parameters(EVP_PKEY *pkey, STACK_OF(X509) *chain)
1982 {
1983 EVP_PKEY *ktmp = NULL, *ktmp2;
1984 int i, j;
1985
1986 if (pkey != NULL && !EVP_PKEY_missing_parameters(pkey))
1987 return 1;
1988
1989 for (i = 0; i < sk_X509_num(chain); i++) {
1990 ktmp = X509_get0_pubkey(sk_X509_value(chain, i));
1991 if (ktmp == NULL) {
1992 ERR_raise(ERR_LIB_X509, X509_R_UNABLE_TO_GET_CERTS_PUBLIC_KEY);
1993 return 0;
1994 }
1995 if (!EVP_PKEY_missing_parameters(ktmp))
1996 break;
1997 ktmp = NULL;
1998 }
1999 if (ktmp == NULL) {
2000 ERR_raise(ERR_LIB_X509, X509_R_UNABLE_TO_FIND_PARAMETERS_IN_CHAIN);
2001 return 0;
2002 }
2003
2004 /* first, populate the other certs */
2005 for (j = i - 1; j >= 0; j--) {
2006 ktmp2 = X509_get0_pubkey(sk_X509_value(chain, j));
2007 if (!EVP_PKEY_copy_parameters(ktmp2, ktmp))
2008 return 0;
2009 }
2010
2011 if (pkey != NULL)
2012 return EVP_PKEY_copy_parameters(pkey, ktmp);
2013 return 1;
2014 }
2015
2016 /*
2017 * Make a delta CRL as the difference between two full CRLs.
2018 * Sadly, returns NULL also on internal error.
2019 */
X509_CRL_diff(X509_CRL * base,X509_CRL * newer,EVP_PKEY * skey,const EVP_MD * md,unsigned int flags)2020 X509_CRL *X509_CRL_diff(X509_CRL *base, X509_CRL *newer,
2021 EVP_PKEY *skey, const EVP_MD *md, unsigned int flags)
2022 {
2023 X509_CRL *crl = NULL;
2024 int i;
2025
2026 STACK_OF(X509_REVOKED) *revs = NULL;
2027 /* CRLs can't be delta already */
2028 if (base->base_crl_number != NULL || newer->base_crl_number != NULL) {
2029 ERR_raise(ERR_LIB_X509, X509_R_CRL_ALREADY_DELTA);
2030 return NULL;
2031 }
2032 /* Base and new CRL must have a CRL number */
2033 if (base->crl_number == NULL || newer->crl_number == NULL) {
2034 ERR_raise(ERR_LIB_X509, X509_R_NO_CRL_NUMBER);
2035 return NULL;
2036 }
2037 /* Issuer names must match */
2038 if (X509_NAME_cmp(X509_CRL_get_issuer(base),
2039 X509_CRL_get_issuer(newer)) != 0) {
2040 ERR_raise(ERR_LIB_X509, X509_R_ISSUER_MISMATCH);
2041 return NULL;
2042 }
2043 /* AKID and IDP must match */
2044 if (!crl_extension_match(base, newer, NID_authority_key_identifier)) {
2045 ERR_raise(ERR_LIB_X509, X509_R_AKID_MISMATCH);
2046 return NULL;
2047 }
2048 if (!crl_extension_match(base, newer, NID_issuing_distribution_point)) {
2049 ERR_raise(ERR_LIB_X509, X509_R_IDP_MISMATCH);
2050 return NULL;
2051 }
2052 /* Newer CRL number must exceed full CRL number */
2053 if (ASN1_INTEGER_cmp(newer->crl_number, base->crl_number) <= 0) {
2054 ERR_raise(ERR_LIB_X509, X509_R_NEWER_CRL_NOT_NEWER);
2055 return NULL;
2056 }
2057 /* CRLs must verify */
2058 if (skey != NULL && (X509_CRL_verify(base, skey) <= 0 ||
2059 X509_CRL_verify(newer, skey) <= 0)) {
2060 ERR_raise(ERR_LIB_X509, X509_R_CRL_VERIFY_FAILURE);
2061 return NULL;
2062 }
2063 /* Create new CRL */
2064 crl = X509_CRL_new_ex(base->libctx, base->propq);
2065 if (crl == NULL || !X509_CRL_set_version(crl, X509_CRL_VERSION_2))
2066 goto memerr;
2067 /* Set issuer name */
2068 if (!X509_CRL_set_issuer_name(crl, X509_CRL_get_issuer(newer)))
2069 goto memerr;
2070
2071 if (!X509_CRL_set1_lastUpdate(crl, X509_CRL_get0_lastUpdate(newer)))
2072 goto memerr;
2073 if (!X509_CRL_set1_nextUpdate(crl, X509_CRL_get0_nextUpdate(newer)))
2074 goto memerr;
2075
2076 /* Set base CRL number: must be critical */
2077 if (!X509_CRL_add1_ext_i2d(crl, NID_delta_crl, base->crl_number, 1, 0))
2078 goto memerr;
2079
2080 /*
2081 * Copy extensions across from newest CRL to delta: this will set CRL
2082 * number to correct value too.
2083 */
2084 for (i = 0; i < X509_CRL_get_ext_count(newer); i++) {
2085 X509_EXTENSION *ext = X509_CRL_get_ext(newer, i);
2086
2087 if (!X509_CRL_add_ext(crl, ext, -1))
2088 goto memerr;
2089 }
2090
2091 /* Go through revoked entries, copying as needed */
2092 revs = X509_CRL_get_REVOKED(newer);
2093
2094 for (i = 0; i < sk_X509_REVOKED_num(revs); i++) {
2095 X509_REVOKED *rvn, *rvtmp;
2096
2097 rvn = sk_X509_REVOKED_value(revs, i);
2098 /*
2099 * Add only if not also in base.
2100 * Need something cleverer here for some more complex CRLs covering
2101 * multiple CAs.
2102 */
2103 if (!X509_CRL_get0_by_serial(base, &rvtmp, &rvn->serialNumber)) {
2104 rvtmp = X509_REVOKED_dup(rvn);
2105 if (rvtmp == NULL)
2106 goto memerr;
2107 if (!X509_CRL_add0_revoked(crl, rvtmp)) {
2108 X509_REVOKED_free(rvtmp);
2109 goto memerr;
2110 }
2111 }
2112 }
2113
2114 if (skey != NULL && md != NULL && !X509_CRL_sign(crl, skey, md))
2115 goto memerr;
2116
2117 return crl;
2118
2119 memerr:
2120 ERR_raise(ERR_LIB_X509, ERR_R_MALLOC_FAILURE);
2121 X509_CRL_free(crl);
2122 return NULL;
2123 }
2124
X509_STORE_CTX_set_ex_data(X509_STORE_CTX * ctx,int idx,void * data)2125 int X509_STORE_CTX_set_ex_data(X509_STORE_CTX *ctx, int idx, void *data)
2126 {
2127 return CRYPTO_set_ex_data(&ctx->ex_data, idx, data);
2128 }
2129
X509_STORE_CTX_get_ex_data(const X509_STORE_CTX * ctx,int idx)2130 void *X509_STORE_CTX_get_ex_data(const X509_STORE_CTX *ctx, int idx)
2131 {
2132 return CRYPTO_get_ex_data(&ctx->ex_data, idx);
2133 }
2134
X509_STORE_CTX_get_error(const X509_STORE_CTX * ctx)2135 int X509_STORE_CTX_get_error(const X509_STORE_CTX *ctx)
2136 {
2137 return ctx->error;
2138 }
2139
X509_STORE_CTX_set_error(X509_STORE_CTX * ctx,int err)2140 void X509_STORE_CTX_set_error(X509_STORE_CTX *ctx, int err)
2141 {
2142 ctx->error = err;
2143 }
2144
X509_STORE_CTX_get_error_depth(const X509_STORE_CTX * ctx)2145 int X509_STORE_CTX_get_error_depth(const X509_STORE_CTX *ctx)
2146 {
2147 return ctx->error_depth;
2148 }
2149
X509_STORE_CTX_set_error_depth(X509_STORE_CTX * ctx,int depth)2150 void X509_STORE_CTX_set_error_depth(X509_STORE_CTX *ctx, int depth)
2151 {
2152 ctx->error_depth = depth;
2153 }
2154
X509_STORE_CTX_get_current_cert(const X509_STORE_CTX * ctx)2155 X509 *X509_STORE_CTX_get_current_cert(const X509_STORE_CTX *ctx)
2156 {
2157 return ctx->current_cert;
2158 }
2159
X509_STORE_CTX_set_current_cert(X509_STORE_CTX * ctx,X509 * x)2160 void X509_STORE_CTX_set_current_cert(X509_STORE_CTX *ctx, X509 *x)
2161 {
2162 ctx->current_cert = x;
2163 }
2164
STACK_OF(X509)2165 STACK_OF(X509) *X509_STORE_CTX_get0_chain(const X509_STORE_CTX *ctx)
2166 {
2167 return ctx->chain;
2168 }
2169
STACK_OF(X509)2170 STACK_OF(X509) *X509_STORE_CTX_get1_chain(const X509_STORE_CTX *ctx)
2171 {
2172 if (ctx->chain == NULL)
2173 return NULL;
2174 return X509_chain_up_ref(ctx->chain);
2175 }
2176
X509_STORE_CTX_get0_current_issuer(const X509_STORE_CTX * ctx)2177 X509 *X509_STORE_CTX_get0_current_issuer(const X509_STORE_CTX *ctx)
2178 {
2179 return ctx->current_issuer;
2180 }
2181
X509_STORE_CTX_get0_current_crl(const X509_STORE_CTX * ctx)2182 X509_CRL *X509_STORE_CTX_get0_current_crl(const X509_STORE_CTX *ctx)
2183 {
2184 return ctx->current_crl;
2185 }
2186
X509_STORE_CTX_get0_parent_ctx(const X509_STORE_CTX * ctx)2187 X509_STORE_CTX *X509_STORE_CTX_get0_parent_ctx(const X509_STORE_CTX *ctx)
2188 {
2189 return ctx->parent;
2190 }
2191
X509_STORE_CTX_set_cert(X509_STORE_CTX * ctx,X509 * x)2192 void X509_STORE_CTX_set_cert(X509_STORE_CTX *ctx, X509 *x)
2193 {
2194 ctx->cert = x;
2195 }
2196
X509_STORE_CTX_set0_crls(X509_STORE_CTX * ctx,STACK_OF (X509_CRL)* sk)2197 void X509_STORE_CTX_set0_crls(X509_STORE_CTX *ctx, STACK_OF(X509_CRL) *sk)
2198 {
2199 ctx->crls = sk;
2200 }
2201
X509_STORE_CTX_set_purpose(X509_STORE_CTX * ctx,int purpose)2202 int X509_STORE_CTX_set_purpose(X509_STORE_CTX *ctx, int purpose)
2203 {
2204 /*
2205 * XXX: Why isn't this function always used to set the associated trust?
2206 * Should there even be a VPM->trust field at all? Or should the trust
2207 * always be inferred from the purpose by X509_STORE_CTX_init().
2208 */
2209 return X509_STORE_CTX_purpose_inherit(ctx, 0, purpose, 0);
2210 }
2211
X509_STORE_CTX_set_trust(X509_STORE_CTX * ctx,int trust)2212 int X509_STORE_CTX_set_trust(X509_STORE_CTX *ctx, int trust)
2213 {
2214 /*
2215 * XXX: See above, this function would only be needed when the default
2216 * trust for the purpose needs an override in a corner case.
2217 */
2218 return X509_STORE_CTX_purpose_inherit(ctx, 0, 0, trust);
2219 }
2220
2221 /*
2222 * This function is used to set the X509_STORE_CTX purpose and trust values.
2223 * This is intended to be used when another structure has its own trust and
2224 * purpose values which (if set) will be inherited by the ctx. If they aren't
2225 * set then we will usually have a default purpose in mind which should then
2226 * be used to set the trust value. An example of this is SSL use: an SSL
2227 * structure will have its own purpose and trust settings which the
2228 * application can set: if they aren't set then we use the default of SSL
2229 * client/server.
2230 */
X509_STORE_CTX_purpose_inherit(X509_STORE_CTX * ctx,int def_purpose,int purpose,int trust)2231 int X509_STORE_CTX_purpose_inherit(X509_STORE_CTX *ctx, int def_purpose,
2232 int purpose, int trust)
2233 {
2234 int idx;
2235
2236 /* If purpose not set use default */
2237 if (purpose == 0)
2238 purpose = def_purpose;
2239 /*
2240 * If purpose is set but we don't have a default then set the default to
2241 * the current purpose
2242 */
2243 else if (def_purpose == 0)
2244 def_purpose = purpose;
2245 /* If we have a purpose then check it is valid */
2246 if (purpose != 0) {
2247 X509_PURPOSE *ptmp;
2248
2249 idx = X509_PURPOSE_get_by_id(purpose);
2250 if (idx == -1) {
2251 ERR_raise(ERR_LIB_X509, X509_R_UNKNOWN_PURPOSE_ID);
2252 return 0;
2253 }
2254 ptmp = X509_PURPOSE_get0(idx);
2255 if (ptmp->trust == X509_TRUST_DEFAULT) {
2256 idx = X509_PURPOSE_get_by_id(def_purpose);
2257 if (idx == -1) {
2258 ERR_raise(ERR_LIB_X509, X509_R_UNKNOWN_PURPOSE_ID);
2259 return 0;
2260 }
2261 ptmp = X509_PURPOSE_get0(idx);
2262 }
2263 /* If trust not set then get from purpose default */
2264 if (trust == 0)
2265 trust = ptmp->trust;
2266 }
2267 if (trust != 0) {
2268 idx = X509_TRUST_get_by_id(trust);
2269 if (idx == -1) {
2270 ERR_raise(ERR_LIB_X509, X509_R_UNKNOWN_TRUST_ID);
2271 return 0;
2272 }
2273 }
2274
2275 if (ctx->param->purpose == 0 && purpose != 0)
2276 ctx->param->purpose = purpose;
2277 if (ctx->param->trust == 0 && trust != 0)
2278 ctx->param->trust = trust;
2279 return 1;
2280 }
2281
X509_STORE_CTX_new_ex(OSSL_LIB_CTX * libctx,const char * propq)2282 X509_STORE_CTX *X509_STORE_CTX_new_ex(OSSL_LIB_CTX *libctx, const char *propq)
2283 {
2284 X509_STORE_CTX *ctx = OPENSSL_zalloc(sizeof(*ctx));
2285
2286 if (ctx == NULL) {
2287 ERR_raise(ERR_LIB_X509, ERR_R_MALLOC_FAILURE);
2288 return NULL;
2289 }
2290
2291 ctx->libctx = libctx;
2292 if (propq != NULL) {
2293 ctx->propq = OPENSSL_strdup(propq);
2294 if (ctx->propq == NULL) {
2295 OPENSSL_free(ctx);
2296 ERR_raise(ERR_LIB_X509, ERR_R_MALLOC_FAILURE);
2297 return NULL;
2298 }
2299 }
2300
2301 return ctx;
2302 }
2303
X509_STORE_CTX_new(void)2304 X509_STORE_CTX *X509_STORE_CTX_new(void)
2305 {
2306 return X509_STORE_CTX_new_ex(NULL, NULL);
2307 }
2308
X509_STORE_CTX_free(X509_STORE_CTX * ctx)2309 void X509_STORE_CTX_free(X509_STORE_CTX *ctx)
2310 {
2311 if (ctx == NULL)
2312 return;
2313
2314 X509_STORE_CTX_cleanup(ctx);
2315
2316 /* libctx and propq survive X509_STORE_CTX_cleanup() */
2317 OPENSSL_free(ctx->propq);
2318 OPENSSL_free(ctx);
2319 }
2320
X509_STORE_CTX_init(X509_STORE_CTX * ctx,X509_STORE * store,X509 * x509,STACK_OF (X509)* chain)2321 int X509_STORE_CTX_init(X509_STORE_CTX *ctx, X509_STORE *store, X509 *x509,
2322 STACK_OF(X509) *chain)
2323 {
2324 if (ctx == NULL) {
2325 ERR_raise(ERR_LIB_X509, ERR_R_PASSED_NULL_PARAMETER);
2326 return 0;
2327 }
2328 X509_STORE_CTX_cleanup(ctx);
2329
2330 ctx->store = store;
2331 ctx->cert = x509;
2332 ctx->untrusted = chain;
2333 ctx->crls = NULL;
2334 ctx->num_untrusted = 0;
2335 ctx->other_ctx = NULL;
2336 ctx->valid = 0;
2337 ctx->chain = NULL;
2338 ctx->error = X509_V_OK;
2339 ctx->explicit_policy = 0;
2340 ctx->error_depth = 0;
2341 ctx->current_cert = NULL;
2342 ctx->current_issuer = NULL;
2343 ctx->current_crl = NULL;
2344 ctx->current_crl_score = 0;
2345 ctx->current_reasons = 0;
2346 ctx->tree = NULL;
2347 ctx->parent = NULL;
2348 ctx->dane = NULL;
2349 ctx->bare_ta_signed = 0;
2350 /* Zero ex_data to make sure we're cleanup-safe */
2351 memset(&ctx->ex_data, 0, sizeof(ctx->ex_data));
2352
2353 /* store->cleanup is always 0 in OpenSSL, if set must be idempotent */
2354 if (store != NULL)
2355 ctx->cleanup = store->cleanup;
2356 else
2357 ctx->cleanup = NULL;
2358
2359 if (store != NULL && store->check_issued != NULL)
2360 ctx->check_issued = store->check_issued;
2361 else
2362 ctx->check_issued = check_issued;
2363
2364 if (store != NULL && store->get_issuer != NULL)
2365 ctx->get_issuer = store->get_issuer;
2366 else
2367 ctx->get_issuer = X509_STORE_CTX_get1_issuer;
2368
2369 if (store != NULL && store->verify_cb != NULL)
2370 ctx->verify_cb = store->verify_cb;
2371 else
2372 ctx->verify_cb = null_callback;
2373
2374 if (store != NULL && store->verify != NULL)
2375 ctx->verify = store->verify;
2376 else
2377 ctx->verify = internal_verify;
2378
2379 if (store != NULL && store->check_revocation != NULL)
2380 ctx->check_revocation = store->check_revocation;
2381 else
2382 ctx->check_revocation = check_revocation;
2383
2384 if (store != NULL && store->get_crl != NULL)
2385 ctx->get_crl = store->get_crl;
2386 else
2387 ctx->get_crl = NULL;
2388
2389 if (store != NULL && store->check_crl != NULL)
2390 ctx->check_crl = store->check_crl;
2391 else
2392 ctx->check_crl = check_crl;
2393
2394 if (store != NULL && store->cert_crl != NULL)
2395 ctx->cert_crl = store->cert_crl;
2396 else
2397 ctx->cert_crl = cert_crl;
2398
2399 if (store != NULL && store->check_policy != NULL)
2400 ctx->check_policy = store->check_policy;
2401 else
2402 ctx->check_policy = check_policy;
2403
2404 if (store != NULL && store->lookup_certs != NULL)
2405 ctx->lookup_certs = store->lookup_certs;
2406 else
2407 ctx->lookup_certs = X509_STORE_CTX_get1_certs;
2408
2409 if (store != NULL && store->lookup_crls != NULL)
2410 ctx->lookup_crls = store->lookup_crls;
2411 else
2412 ctx->lookup_crls = X509_STORE_CTX_get1_crls;
2413
2414 ctx->param = X509_VERIFY_PARAM_new();
2415 if (ctx->param == NULL) {
2416 ERR_raise(ERR_LIB_X509, ERR_R_MALLOC_FAILURE);
2417 goto err;
2418 }
2419
2420 /* Inherit callbacks and flags from X509_STORE if not set use defaults. */
2421 if (store == NULL)
2422 ctx->param->inh_flags |= X509_VP_FLAG_DEFAULT | X509_VP_FLAG_ONCE;
2423 else if (X509_VERIFY_PARAM_inherit(ctx->param, store->param) == 0)
2424 goto err;
2425
2426 if (!X509_STORE_CTX_set_default(ctx, "default"))
2427 goto err;
2428
2429 /*
2430 * XXX: For now, continue to inherit trust from VPM, but infer from the
2431 * purpose if this still yields the default value.
2432 */
2433 if (ctx->param->trust == X509_TRUST_DEFAULT) {
2434 int idx = X509_PURPOSE_get_by_id(ctx->param->purpose);
2435 X509_PURPOSE *xp = X509_PURPOSE_get0(idx);
2436
2437 if (xp != NULL)
2438 ctx->param->trust = X509_PURPOSE_get_trust(xp);
2439 }
2440
2441 if (CRYPTO_new_ex_data(CRYPTO_EX_INDEX_X509_STORE_CTX, ctx,
2442 &ctx->ex_data))
2443 return 1;
2444 ERR_raise(ERR_LIB_X509, ERR_R_MALLOC_FAILURE);
2445
2446 err:
2447 /*
2448 * On error clean up allocated storage, if the store context was not
2449 * allocated with X509_STORE_CTX_new() this is our last chance to do so.
2450 */
2451 X509_STORE_CTX_cleanup(ctx);
2452 return 0;
2453 }
2454
2455 /*
2456 * Set alternative get_issuer method: just from a STACK of trusted certificates.
2457 * This avoids the complexity of X509_STORE where it is not needed.
2458 */
X509_STORE_CTX_set0_trusted_stack(X509_STORE_CTX * ctx,STACK_OF (X509)* sk)2459 void X509_STORE_CTX_set0_trusted_stack(X509_STORE_CTX *ctx, STACK_OF(X509) *sk)
2460 {
2461 ctx->other_ctx = sk;
2462 ctx->get_issuer = get_issuer_sk;
2463 ctx->lookup_certs = lookup_certs_sk;
2464 }
2465
X509_STORE_CTX_cleanup(X509_STORE_CTX * ctx)2466 void X509_STORE_CTX_cleanup(X509_STORE_CTX *ctx)
2467 {
2468 /*
2469 * We need to be idempotent because, unfortunately, free() also calls
2470 * cleanup(), so the natural call sequence new(), init(), cleanup(), free()
2471 * calls cleanup() for the same object twice! Thus we must zero the
2472 * pointers below after they're freed!
2473 */
2474 /* Seems to always be NULL in OpenSSL, do this at most once. */
2475 if (ctx->cleanup != NULL) {
2476 ctx->cleanup(ctx);
2477 ctx->cleanup = NULL;
2478 }
2479 if (ctx->param != NULL) {
2480 if (ctx->parent == NULL)
2481 X509_VERIFY_PARAM_free(ctx->param);
2482 ctx->param = NULL;
2483 }
2484 X509_policy_tree_free(ctx->tree);
2485 ctx->tree = NULL;
2486 sk_X509_pop_free(ctx->chain, X509_free);
2487 ctx->chain = NULL;
2488 CRYPTO_free_ex_data(CRYPTO_EX_INDEX_X509_STORE_CTX, ctx, &(ctx->ex_data));
2489 memset(&ctx->ex_data, 0, sizeof(ctx->ex_data));
2490 }
2491
X509_STORE_CTX_set_depth(X509_STORE_CTX * ctx,int depth)2492 void X509_STORE_CTX_set_depth(X509_STORE_CTX *ctx, int depth)
2493 {
2494 X509_VERIFY_PARAM_set_depth(ctx->param, depth);
2495 }
2496
X509_STORE_CTX_set_flags(X509_STORE_CTX * ctx,unsigned long flags)2497 void X509_STORE_CTX_set_flags(X509_STORE_CTX *ctx, unsigned long flags)
2498 {
2499 X509_VERIFY_PARAM_set_flags(ctx->param, flags);
2500 }
2501
X509_STORE_CTX_set_time(X509_STORE_CTX * ctx,unsigned long flags,time_t t)2502 void X509_STORE_CTX_set_time(X509_STORE_CTX *ctx, unsigned long flags,
2503 time_t t)
2504 {
2505 X509_VERIFY_PARAM_set_time(ctx->param, t);
2506 }
2507
X509_STORE_CTX_get0_cert(const X509_STORE_CTX * ctx)2508 X509 *X509_STORE_CTX_get0_cert(const X509_STORE_CTX *ctx)
2509 {
2510 return ctx->cert;
2511 }
2512
STACK_OF(X509)2513 STACK_OF(X509) *X509_STORE_CTX_get0_untrusted(const X509_STORE_CTX *ctx)
2514 {
2515 return ctx->untrusted;
2516 }
2517
X509_STORE_CTX_set0_untrusted(X509_STORE_CTX * ctx,STACK_OF (X509)* sk)2518 void X509_STORE_CTX_set0_untrusted(X509_STORE_CTX *ctx, STACK_OF(X509) *sk)
2519 {
2520 ctx->untrusted = sk;
2521 }
2522
X509_STORE_CTX_set0_verified_chain(X509_STORE_CTX * ctx,STACK_OF (X509)* sk)2523 void X509_STORE_CTX_set0_verified_chain(X509_STORE_CTX *ctx, STACK_OF(X509) *sk)
2524 {
2525 sk_X509_pop_free(ctx->chain, X509_free);
2526 ctx->chain = sk;
2527 }
2528
X509_STORE_CTX_set_verify_cb(X509_STORE_CTX * ctx,X509_STORE_CTX_verify_cb verify_cb)2529 void X509_STORE_CTX_set_verify_cb(X509_STORE_CTX *ctx,
2530 X509_STORE_CTX_verify_cb verify_cb)
2531 {
2532 ctx->verify_cb = verify_cb;
2533 }
2534
X509_STORE_CTX_get_verify_cb(const X509_STORE_CTX * ctx)2535 X509_STORE_CTX_verify_cb X509_STORE_CTX_get_verify_cb(const X509_STORE_CTX *ctx)
2536 {
2537 return ctx->verify_cb;
2538 }
2539
X509_STORE_CTX_set_verify(X509_STORE_CTX * ctx,X509_STORE_CTX_verify_fn verify)2540 void X509_STORE_CTX_set_verify(X509_STORE_CTX *ctx,
2541 X509_STORE_CTX_verify_fn verify)
2542 {
2543 ctx->verify = verify;
2544 }
2545
X509_STORE_CTX_get_verify(const X509_STORE_CTX * ctx)2546 X509_STORE_CTX_verify_fn X509_STORE_CTX_get_verify(const X509_STORE_CTX *ctx)
2547 {
2548 return ctx->verify;
2549 }
2550
2551 X509_STORE_CTX_get_issuer_fn
X509_STORE_CTX_get_get_issuer(const X509_STORE_CTX * ctx)2552 X509_STORE_CTX_get_get_issuer(const X509_STORE_CTX *ctx)
2553 {
2554 return ctx->get_issuer;
2555 }
2556
2557 X509_STORE_CTX_check_issued_fn
X509_STORE_CTX_get_check_issued(const X509_STORE_CTX * ctx)2558 X509_STORE_CTX_get_check_issued(const X509_STORE_CTX *ctx)
2559 {
2560 return ctx->check_issued;
2561 }
2562
2563 X509_STORE_CTX_check_revocation_fn
X509_STORE_CTX_get_check_revocation(const X509_STORE_CTX * ctx)2564 X509_STORE_CTX_get_check_revocation(const X509_STORE_CTX *ctx)
2565 {
2566 return ctx->check_revocation;
2567 }
2568
X509_STORE_CTX_get_get_crl(const X509_STORE_CTX * ctx)2569 X509_STORE_CTX_get_crl_fn X509_STORE_CTX_get_get_crl(const X509_STORE_CTX *ctx)
2570 {
2571 return ctx->get_crl;
2572 }
2573
2574 X509_STORE_CTX_check_crl_fn
X509_STORE_CTX_get_check_crl(const X509_STORE_CTX * ctx)2575 X509_STORE_CTX_get_check_crl(const X509_STORE_CTX *ctx)
2576 {
2577 return ctx->check_crl;
2578 }
2579
2580 X509_STORE_CTX_cert_crl_fn
X509_STORE_CTX_get_cert_crl(const X509_STORE_CTX * ctx)2581 X509_STORE_CTX_get_cert_crl(const X509_STORE_CTX *ctx)
2582 {
2583 return ctx->cert_crl;
2584 }
2585
2586 X509_STORE_CTX_check_policy_fn
X509_STORE_CTX_get_check_policy(const X509_STORE_CTX * ctx)2587 X509_STORE_CTX_get_check_policy(const X509_STORE_CTX *ctx)
2588 {
2589 return ctx->check_policy;
2590 }
2591
2592 X509_STORE_CTX_lookup_certs_fn
X509_STORE_CTX_get_lookup_certs(const X509_STORE_CTX * ctx)2593 X509_STORE_CTX_get_lookup_certs(const X509_STORE_CTX *ctx)
2594 {
2595 return ctx->lookup_certs;
2596 }
2597
2598 X509_STORE_CTX_lookup_crls_fn
X509_STORE_CTX_get_lookup_crls(const X509_STORE_CTX * ctx)2599 X509_STORE_CTX_get_lookup_crls(const X509_STORE_CTX *ctx)
2600 {
2601 return ctx->lookup_crls;
2602 }
2603
X509_STORE_CTX_get_cleanup(const X509_STORE_CTX * ctx)2604 X509_STORE_CTX_cleanup_fn X509_STORE_CTX_get_cleanup(const X509_STORE_CTX *ctx)
2605 {
2606 return ctx->cleanup;
2607 }
2608
X509_STORE_CTX_get0_policy_tree(const X509_STORE_CTX * ctx)2609 X509_POLICY_TREE *X509_STORE_CTX_get0_policy_tree(const X509_STORE_CTX *ctx)
2610 {
2611 return ctx->tree;
2612 }
2613
X509_STORE_CTX_get_explicit_policy(const X509_STORE_CTX * ctx)2614 int X509_STORE_CTX_get_explicit_policy(const X509_STORE_CTX *ctx)
2615 {
2616 return ctx->explicit_policy;
2617 }
2618
X509_STORE_CTX_get_num_untrusted(const X509_STORE_CTX * ctx)2619 int X509_STORE_CTX_get_num_untrusted(const X509_STORE_CTX *ctx)
2620 {
2621 return ctx->num_untrusted;
2622 }
2623
X509_STORE_CTX_set_default(X509_STORE_CTX * ctx,const char * name)2624 int X509_STORE_CTX_set_default(X509_STORE_CTX *ctx, const char *name)
2625 {
2626 const X509_VERIFY_PARAM *param;
2627
2628 param = X509_VERIFY_PARAM_lookup(name);
2629 if (param == NULL) {
2630 ERR_raise_data(ERR_LIB_X509, X509_R_UNKNOWN_PURPOSE_ID, "name=%s", name);
2631 return 0;
2632 }
2633 return X509_VERIFY_PARAM_inherit(ctx->param, param);
2634 }
2635
X509_STORE_CTX_get0_param(const X509_STORE_CTX * ctx)2636 X509_VERIFY_PARAM *X509_STORE_CTX_get0_param(const X509_STORE_CTX *ctx)
2637 {
2638 return ctx->param;
2639 }
2640
X509_STORE_CTX_set0_param(X509_STORE_CTX * ctx,X509_VERIFY_PARAM * param)2641 void X509_STORE_CTX_set0_param(X509_STORE_CTX *ctx, X509_VERIFY_PARAM *param)
2642 {
2643 X509_VERIFY_PARAM_free(ctx->param);
2644 ctx->param = param;
2645 }
2646
X509_STORE_CTX_set0_dane(X509_STORE_CTX * ctx,SSL_DANE * dane)2647 void X509_STORE_CTX_set0_dane(X509_STORE_CTX *ctx, SSL_DANE *dane)
2648 {
2649 ctx->dane = dane;
2650 }
2651
dane_i2d(X509 * cert,uint8_t selector,unsigned int * i2dlen)2652 static unsigned char *dane_i2d(X509 *cert, uint8_t selector,
2653 unsigned int *i2dlen)
2654 {
2655 unsigned char *buf = NULL;
2656 int len;
2657
2658 /*
2659 * Extract ASN.1 DER form of certificate or public key.
2660 */
2661 switch (selector) {
2662 case DANETLS_SELECTOR_CERT:
2663 len = i2d_X509(cert, &buf);
2664 break;
2665 case DANETLS_SELECTOR_SPKI:
2666 len = i2d_X509_PUBKEY(X509_get_X509_PUBKEY(cert), &buf);
2667 break;
2668 default:
2669 ERR_raise(ERR_LIB_X509, X509_R_BAD_SELECTOR);
2670 return NULL;
2671 }
2672
2673 if (len < 0 || buf == NULL) {
2674 ERR_raise(ERR_LIB_X509, ERR_R_MALLOC_FAILURE);
2675 return NULL;
2676 }
2677
2678 *i2dlen = (unsigned int)len;
2679 return buf;
2680 }
2681
2682 #define DANETLS_NONE 256 /* impossible uint8_t */
2683
2684 /* Returns -1 on internal error */
dane_match(X509_STORE_CTX * ctx,X509 * cert,int depth)2685 static int dane_match(X509_STORE_CTX *ctx, X509 *cert, int depth)
2686 {
2687 SSL_DANE *dane = ctx->dane;
2688 unsigned usage = DANETLS_NONE;
2689 unsigned selector = DANETLS_NONE;
2690 unsigned ordinal = DANETLS_NONE;
2691 unsigned mtype = DANETLS_NONE;
2692 unsigned char *i2dbuf = NULL;
2693 unsigned int i2dlen = 0;
2694 unsigned char mdbuf[EVP_MAX_MD_SIZE];
2695 unsigned char *cmpbuf = NULL;
2696 unsigned int cmplen = 0;
2697 int i;
2698 int recnum;
2699 int matched = 0;
2700 danetls_record *t = NULL;
2701 uint32_t mask;
2702
2703 mask = (depth == 0) ? DANETLS_EE_MASK : DANETLS_TA_MASK;
2704
2705 /* The trust store is not applicable with DANE-TA(2) */
2706 if (depth >= ctx->num_untrusted)
2707 mask &= DANETLS_PKIX_MASK;
2708
2709 /*
2710 * If we've previously matched a PKIX-?? record, no need to test any
2711 * further PKIX-?? records, it remains to just build the PKIX chain.
2712 * Had the match been a DANE-?? record, we'd be done already.
2713 */
2714 if (dane->mdpth >= 0)
2715 mask &= ~DANETLS_PKIX_MASK;
2716
2717 /*-
2718 * https://tools.ietf.org/html/rfc7671#section-5.1
2719 * https://tools.ietf.org/html/rfc7671#section-5.2
2720 * https://tools.ietf.org/html/rfc7671#section-5.3
2721 * https://tools.ietf.org/html/rfc7671#section-5.4
2722 *
2723 * We handle DANE-EE(3) records first as they require no chain building
2724 * and no expiration or hostname checks. We also process digests with
2725 * higher ordinals first and ignore lower priorities except Full(0) which
2726 * is always processed (last). If none match, we then process PKIX-EE(1).
2727 *
2728 * NOTE: This relies on DANE usages sorting before the corresponding PKIX
2729 * usages in SSL_dane_tlsa_add(), and also on descending sorting of digest
2730 * priorities. See twin comment in ssl/ssl_lib.c.
2731 *
2732 * We expect that most TLSA RRsets will have just a single usage, so we
2733 * don't go out of our way to cache multiple selector-specific i2d buffers
2734 * across usages, but if the selector happens to remain the same as switch
2735 * usages, that's OK. Thus, a set of "3 1 1", "3 0 1", "1 1 1", "1 0 1",
2736 * records would result in us generating each of the certificate and public
2737 * key DER forms twice, but more typically we'd just see multiple "3 1 1"
2738 * or multiple "3 0 1" records.
2739 *
2740 * As soon as we find a match at any given depth, we stop, because either
2741 * we've matched a DANE-?? record and the peer is authenticated, or, after
2742 * exhausting all DANE-?? records, we've matched a PKIX-?? record, which is
2743 * sufficient for DANE, and what remains to do is ordinary PKIX validation.
2744 */
2745 recnum = (dane->umask & mask) != 0 ? sk_danetls_record_num(dane->trecs) : 0;
2746 for (i = 0; matched == 0 && i < recnum; ++i) {
2747 t = sk_danetls_record_value(dane->trecs, i);
2748 if ((DANETLS_USAGE_BIT(t->usage) & mask) == 0)
2749 continue;
2750 if (t->usage != usage) {
2751 usage = t->usage;
2752
2753 /* Reset digest agility for each usage/selector pair */
2754 mtype = DANETLS_NONE;
2755 ordinal = dane->dctx->mdord[t->mtype];
2756 }
2757 if (t->selector != selector) {
2758 selector = t->selector;
2759
2760 /* Update per-selector state */
2761 OPENSSL_free(i2dbuf);
2762 i2dbuf = dane_i2d(cert, selector, &i2dlen);
2763 if (i2dbuf == NULL)
2764 return -1;
2765
2766 /* Reset digest agility for each usage/selector pair */
2767 mtype = DANETLS_NONE;
2768 ordinal = dane->dctx->mdord[t->mtype];
2769 } else if (t->mtype != DANETLS_MATCHING_FULL) {
2770 /*-
2771 * Digest agility:
2772 *
2773 * <https://tools.ietf.org/html/rfc7671#section-9>
2774 *
2775 * For a fixed selector, after processing all records with the
2776 * highest mtype ordinal, ignore all mtypes with lower ordinals
2777 * other than "Full".
2778 */
2779 if (dane->dctx->mdord[t->mtype] < ordinal)
2780 continue;
2781 }
2782
2783 /*
2784 * Each time we hit a (new selector or) mtype, re-compute the relevant
2785 * digest, more complex caching is not worth the code space.
2786 */
2787 if (t->mtype != mtype) {
2788 const EVP_MD *md = dane->dctx->mdevp[mtype = t->mtype];
2789
2790 cmpbuf = i2dbuf;
2791 cmplen = i2dlen;
2792
2793 if (md != NULL) {
2794 cmpbuf = mdbuf;
2795 if (!EVP_Digest(i2dbuf, i2dlen, cmpbuf, &cmplen, md, 0)) {
2796 matched = -1;
2797 break;
2798 }
2799 }
2800 }
2801
2802 /*
2803 * Squirrel away the certificate and depth if we have a match. Any
2804 * DANE match is dispositive, but with PKIX we still need to build a
2805 * full chain.
2806 */
2807 if (cmplen == t->dlen &&
2808 memcmp(cmpbuf, t->data, cmplen) == 0) {
2809 if (DANETLS_USAGE_BIT(usage) & DANETLS_DANE_MASK)
2810 matched = 1;
2811 if (matched || dane->mdpth < 0) {
2812 dane->mdpth = depth;
2813 dane->mtlsa = t;
2814 OPENSSL_free(dane->mcert);
2815 dane->mcert = cert;
2816 X509_up_ref(cert);
2817 }
2818 break;
2819 }
2820 }
2821
2822 /* Clear the one-element DER cache */
2823 OPENSSL_free(i2dbuf);
2824 return matched;
2825 }
2826
2827 /* Returns -1 on internal error */
check_dane_issuer(X509_STORE_CTX * ctx,int depth)2828 static int check_dane_issuer(X509_STORE_CTX *ctx, int depth)
2829 {
2830 SSL_DANE *dane = ctx->dane;
2831 int matched = 0;
2832 X509 *cert;
2833
2834 if (!DANETLS_HAS_TA(dane) || depth == 0)
2835 return X509_TRUST_UNTRUSTED;
2836
2837 /*
2838 * Record any DANE trust anchor matches, for the first depth to test, if
2839 * there's one at that depth. (This'll be false for length 1 chains looking
2840 * for an exact match for the leaf certificate).
2841 */
2842 cert = sk_X509_value(ctx->chain, depth);
2843 if (cert != NULL && (matched = dane_match(ctx, cert, depth)) < 0)
2844 return matched;
2845 if (matched > 0) {
2846 ctx->num_untrusted = depth - 1;
2847 return X509_TRUST_TRUSTED;
2848 }
2849
2850 return X509_TRUST_UNTRUSTED;
2851 }
2852
check_dane_pkeys(X509_STORE_CTX * ctx)2853 static int check_dane_pkeys(X509_STORE_CTX *ctx)
2854 {
2855 SSL_DANE *dane = ctx->dane;
2856 danetls_record *t;
2857 int num = ctx->num_untrusted;
2858 X509 *cert = sk_X509_value(ctx->chain, num - 1);
2859 int recnum = sk_danetls_record_num(dane->trecs);
2860 int i;
2861
2862 for (i = 0; i < recnum; ++i) {
2863 t = sk_danetls_record_value(dane->trecs, i);
2864 if (t->usage != DANETLS_USAGE_DANE_TA ||
2865 t->selector != DANETLS_SELECTOR_SPKI ||
2866 t->mtype != DANETLS_MATCHING_FULL ||
2867 X509_verify(cert, t->spki) <= 0)
2868 continue;
2869
2870 /* Clear any PKIX-?? matches that failed to extend to a full chain */
2871 X509_free(dane->mcert);
2872 dane->mcert = NULL;
2873
2874 /* Record match via a bare TA public key */
2875 ctx->bare_ta_signed = 1;
2876 dane->mdpth = num - 1;
2877 dane->mtlsa = t;
2878
2879 /* Prune any excess chain certificates */
2880 num = sk_X509_num(ctx->chain);
2881 for (; num > ctx->num_untrusted; --num)
2882 X509_free(sk_X509_pop(ctx->chain));
2883
2884 return X509_TRUST_TRUSTED;
2885 }
2886
2887 return X509_TRUST_UNTRUSTED;
2888 }
2889
dane_reset(SSL_DANE * dane)2890 static void dane_reset(SSL_DANE *dane)
2891 {
2892 /* Reset state to verify another chain, or clear after failure. */
2893 X509_free(dane->mcert);
2894 dane->mcert = NULL;
2895 dane->mtlsa = NULL;
2896 dane->mdpth = -1;
2897 dane->pdpth = -1;
2898 }
2899
check_leaf_suiteb(X509_STORE_CTX * ctx,X509 * cert)2900 static int check_leaf_suiteb(X509_STORE_CTX *ctx, X509 *cert)
2901 {
2902 int err = X509_chain_check_suiteb(NULL, cert, NULL, ctx->param->flags);
2903
2904 CB_FAIL_IF(err != X509_V_OK, ctx, cert, 0, err);
2905 return 1;
2906 }
2907
2908 /* Returns -1 on internal error */
dane_verify(X509_STORE_CTX * ctx)2909 static int dane_verify(X509_STORE_CTX *ctx)
2910 {
2911 X509 *cert = ctx->cert;
2912 SSL_DANE *dane = ctx->dane;
2913 int matched;
2914 int done;
2915
2916 dane_reset(dane);
2917
2918 /*-
2919 * When testing the leaf certificate, if we match a DANE-EE(3) record,
2920 * dane_match() returns 1 and we're done. If however we match a PKIX-EE(1)
2921 * record, the match depth and matching TLSA record are recorded, but the
2922 * return value is 0, because we still need to find a PKIX trust anchor.
2923 * Therefore, when DANE authentication is enabled (required), we're done
2924 * if:
2925 * + matched < 0, internal error.
2926 * + matched == 1, we matched a DANE-EE(3) record
2927 * + matched == 0, mdepth < 0 (no PKIX-EE match) and there are no
2928 * DANE-TA(2) or PKIX-TA(0) to test.
2929 */
2930 matched = dane_match(ctx, ctx->cert, 0);
2931 done = matched != 0 || (!DANETLS_HAS_TA(dane) && dane->mdpth < 0);
2932
2933 if (done && !X509_get_pubkey_parameters(NULL, ctx->chain))
2934 return -1;
2935
2936 if (matched > 0) {
2937 /* Callback invoked as needed */
2938 if (!check_leaf_suiteb(ctx, cert))
2939 return 0;
2940 /* Callback invoked as needed */
2941 if ((dane->flags & DANE_FLAG_NO_DANE_EE_NAMECHECKS) == 0 &&
2942 !check_id(ctx))
2943 return 0;
2944 /* Bypass internal_verify(), issue depth 0 success callback */
2945 ctx->error_depth = 0;
2946 ctx->current_cert = cert;
2947 return ctx->verify_cb(1, ctx);
2948 }
2949
2950 if (matched < 0) {
2951 ctx->error_depth = 0;
2952 ctx->current_cert = cert;
2953 ctx->error = X509_V_ERR_OUT_OF_MEM;
2954 return -1;
2955 }
2956
2957 if (done) {
2958 /* Fail early, TA-based success is not possible */
2959 if (!check_leaf_suiteb(ctx, cert))
2960 return 0;
2961 return verify_cb_cert(ctx, cert, 0, X509_V_ERR_DANE_NO_MATCH);
2962 }
2963
2964 /*
2965 * Chain verification for usages 0/1/2. TLSA record matching of depth > 0
2966 * certificates happens in-line with building the rest of the chain.
2967 */
2968 return verify_chain(ctx);
2969 }
2970
2971 /*
2972 * Get trusted issuer, without duplicate suppression
2973 * Returns -1 on internal error.
2974 */
get1_trusted_issuer(X509 ** issuer,X509_STORE_CTX * ctx,X509 * cert)2975 static int get1_trusted_issuer(X509 **issuer, X509_STORE_CTX *ctx, X509 *cert)
2976 {
2977 STACK_OF(X509) *saved_chain = ctx->chain;
2978 int ok;
2979
2980 ctx->chain = NULL;
2981 ok = ctx->get_issuer(issuer, ctx, cert);
2982 ctx->chain = saved_chain;
2983
2984 return ok;
2985 }
2986
2987 /* Returns -1 on internal error */
build_chain(X509_STORE_CTX * ctx)2988 static int build_chain(X509_STORE_CTX *ctx)
2989 {
2990 SSL_DANE *dane = ctx->dane;
2991 int num = sk_X509_num(ctx->chain);
2992 STACK_OF(X509) *sk_untrusted = NULL;
2993 unsigned int search;
2994 int may_trusted = 0;
2995 int may_alternate = 0;
2996 int trust = X509_TRUST_UNTRUSTED;
2997 int alt_untrusted = 0;
2998 int max_depth;
2999 int ok = 0;
3000 int i;
3001
3002 /* Our chain starts with a single untrusted element. */
3003 if (!ossl_assert(num == 1 && ctx->num_untrusted == num))
3004 goto int_err;
3005
3006 #define S_DOUNTRUSTED (1 << 0) /* Search untrusted chain */
3007 #define S_DOTRUSTED (1 << 1) /* Search trusted store */
3008 #define S_DOALTERNATE (1 << 2) /* Retry with pruned alternate chain */
3009 /*
3010 * Set up search policy, untrusted if possible, trusted-first if enabled,
3011 * which is the default.
3012 * If we're doing DANE and not doing PKIX-TA/PKIX-EE, we never look in the
3013 * trust_store, otherwise we might look there first. If not trusted-first,
3014 * and alternate chains are not disabled, try building an alternate chain
3015 * if no luck with untrusted first.
3016 */
3017 search = ctx->untrusted != NULL ? S_DOUNTRUSTED : 0;
3018 if (DANETLS_HAS_PKIX(dane) || !DANETLS_HAS_DANE(dane)) {
3019 if (search == 0 || (ctx->param->flags & X509_V_FLAG_TRUSTED_FIRST) != 0)
3020 search |= S_DOTRUSTED;
3021 else if (!(ctx->param->flags & X509_V_FLAG_NO_ALT_CHAINS))
3022 may_alternate = 1;
3023 may_trusted = 1;
3024 }
3025
3026 /* Initialize empty untrusted stack. */
3027 if ((sk_untrusted = sk_X509_new_null()) == NULL)
3028 goto memerr;
3029
3030 /*
3031 * If we got any "Cert(0) Full(0)" trust anchors from DNS, *prepend* them
3032 * to our working copy of the untrusted certificate stack.
3033 */
3034 if (DANETLS_ENABLED(dane) && dane->certs != NULL
3035 && !X509_add_certs(sk_untrusted, dane->certs, X509_ADD_FLAG_DEFAULT))
3036 goto memerr;
3037
3038 /*
3039 * Shallow-copy the stack of untrusted certificates (with TLS, this is
3040 * typically the content of the peer's certificate message) so we can make
3041 * multiple passes over it, while free to remove elements as we go.
3042 */
3043 if (!X509_add_certs(sk_untrusted, ctx->untrusted, X509_ADD_FLAG_DEFAULT))
3044 goto memerr;
3045
3046 /*
3047 * Still absurdly large, but arithmetically safe, a lower hard upper bound
3048 * might be reasonable.
3049 */
3050 if (ctx->param->depth > INT_MAX / 2)
3051 ctx->param->depth = INT_MAX / 2;
3052
3053 /*
3054 * Try to extend the chain until we reach an ultimately trusted issuer.
3055 * Build chains up to one longer the limit, later fail if we hit the limit,
3056 * with an X509_V_ERR_CERT_CHAIN_TOO_LONG error code.
3057 */
3058 max_depth = ctx->param->depth + 1;
3059
3060 while (search != 0) {
3061 X509 *curr, *issuer = NULL;
3062
3063 num = sk_X509_num(ctx->chain);
3064 ctx->error_depth = num - 1;
3065 /*
3066 * Look in the trust store if enabled for first lookup, or we've run
3067 * out of untrusted issuers and search here is not disabled. When we
3068 * reach the depth limit, we stop extending the chain, if by that point
3069 * we've not found a trust anchor, any trusted chain would be too long.
3070 *
3071 * The error reported to the application verify callback is at the
3072 * maximal valid depth with the current certificate equal to the last
3073 * not ultimately-trusted issuer. For example, with verify_depth = 0,
3074 * the callback will report errors at depth=1 when the immediate issuer
3075 * of the leaf certificate is not a trust anchor. No attempt will be
3076 * made to locate an issuer for that certificate, since such a chain
3077 * would be a-priori too long.
3078 */
3079 if ((search & S_DOTRUSTED) != 0) {
3080 i = num;
3081 if ((search & S_DOALTERNATE) != 0) {
3082 /*
3083 * As high up the chain as we can, look for an alternative
3084 * trusted issuer of an untrusted certificate that currently
3085 * has an untrusted issuer. We use the alt_untrusted variable
3086 * to track how far up the chain we find the first match. It
3087 * is only if and when we find a match, that we prune the chain
3088 * and reset ctx->num_untrusted to the reduced count of
3089 * untrusted certificates. While we're searching for such a
3090 * match (which may never be found), it is neither safe nor
3091 * wise to preemptively modify either the chain or
3092 * ctx->num_untrusted.
3093 *
3094 * Note, like ctx->num_untrusted, alt_untrusted is a count of
3095 * untrusted certificates, not a "depth".
3096 */
3097 i = alt_untrusted;
3098 }
3099 curr = sk_X509_value(ctx->chain, i - 1);
3100
3101 /* Note: get1_trusted_issuer() must be used even if self-signed. */
3102 ok = num > max_depth ? 0 : get1_trusted_issuer(&issuer, ctx, curr);
3103
3104 if (ok < 0) {
3105 trust = -1;
3106 ctx->error = X509_V_ERR_STORE_LOOKUP;
3107 break;
3108 }
3109
3110 if (ok > 0) {
3111 int self_signed = X509_self_signed(curr, 0);
3112
3113 if (self_signed < 0) {
3114 X509_free(issuer);
3115 goto int_err;
3116 }
3117 /*
3118 * Alternative trusted issuer for a mid-chain untrusted cert?
3119 * Pop the untrusted cert's successors and retry. We might now
3120 * be able to complete a valid chain via the trust store. Note
3121 * that despite the current trust store match we might still
3122 * fail complete the chain to a suitable trust anchor, in which
3123 * case we may prune some more untrusted certificates and try
3124 * again. Thus the S_DOALTERNATE bit may yet be turned on
3125 * again with an even shorter untrusted chain!
3126 *
3127 * If in the process we threw away our matching PKIX-TA trust
3128 * anchor, reset DANE trust. We might find a suitable trusted
3129 * certificate among the ones from the trust store.
3130 */
3131 if ((search & S_DOALTERNATE) != 0) {
3132 if (!ossl_assert(num > i && i > 0 && !self_signed)) {
3133 X509_free(issuer);
3134 goto int_err;
3135 }
3136 search &= ~S_DOALTERNATE;
3137 for (; num > i; --num)
3138 X509_free(sk_X509_pop(ctx->chain));
3139 ctx->num_untrusted = num;
3140
3141 if (DANETLS_ENABLED(dane) &&
3142 dane->mdpth >= ctx->num_untrusted) {
3143 dane->mdpth = -1;
3144 X509_free(dane->mcert);
3145 dane->mcert = NULL;
3146 }
3147 if (DANETLS_ENABLED(dane) &&
3148 dane->pdpth >= ctx->num_untrusted)
3149 dane->pdpth = -1;
3150 }
3151
3152 /*
3153 * Self-signed untrusted certificates get replaced by their
3154 * trusted matching issuer. Otherwise, grow the chain.
3155 */
3156 if (!self_signed) {
3157 if (!sk_X509_push(ctx->chain, issuer)) {
3158 X509_free(issuer);
3159 goto memerr;
3160 }
3161 if ((self_signed = X509_self_signed(issuer, 0)) < 0)
3162 goto int_err;
3163 } else {
3164 /*
3165 * We have a self-signed certificate that has the same
3166 * subject name (and perhaps keyid and/or serial number) as
3167 * a trust anchor. We must have an exact match to avoid
3168 * possible impersonation via key substitution etc.
3169 */
3170 if (X509_cmp(curr, issuer) != 0) {
3171 /* Self-signed untrusted mimic. */
3172 X509_free(issuer);
3173 ok = 0;
3174 } else { /* curr "==" issuer */
3175 X509_free(curr);
3176 ctx->num_untrusted = --num;
3177 (void)sk_X509_set(ctx->chain, num, issuer);
3178 }
3179 }
3180
3181 /*
3182 * We've added a new trusted certificate to the chain, re-check
3183 * trust. If not done, and not self-signed look deeper.
3184 * Whether or not we're doing "trusted first", we no longer
3185 * look for untrusted certificates from the peer's chain.
3186 *
3187 * At this point ctx->num_trusted and num must reflect the
3188 * correct number of untrusted certificates, since the DANE
3189 * logic in check_trust() depends on distinguishing CAs from
3190 * "the wire" from CAs from the trust store. In particular, the
3191 * certificate at depth "num" should be the new trusted
3192 * certificate with ctx->num_untrusted <= num.
3193 */
3194 if (ok) {
3195 if (!ossl_assert(ctx->num_untrusted <= num))
3196 goto int_err;
3197 search &= ~S_DOUNTRUSTED;
3198 trust = check_trust(ctx, num);
3199 if (trust != X509_TRUST_UNTRUSTED)
3200 break;
3201 if (!self_signed)
3202 continue;
3203 }
3204 }
3205
3206 /*
3207 * No dispositive decision, and either self-signed or no match, if
3208 * we were doing untrusted-first, and alt-chains are not disabled,
3209 * do that, by repeatedly losing one untrusted element at a time,
3210 * and trying to extend the shorted chain.
3211 */
3212 if ((search & S_DOUNTRUSTED) == 0) {
3213 /* Continue search for a trusted issuer of a shorter chain? */
3214 if ((search & S_DOALTERNATE) != 0 && --alt_untrusted > 0)
3215 continue;
3216 /* Still no luck and no fallbacks left? */
3217 if (!may_alternate || (search & S_DOALTERNATE) != 0 ||
3218 ctx->num_untrusted < 2)
3219 break;
3220 /* Search for a trusted issuer of a shorter chain */
3221 search |= S_DOALTERNATE;
3222 alt_untrusted = ctx->num_untrusted - 1;
3223 }
3224 }
3225
3226 /*
3227 * Extend chain with peer-provided untrusted certificates
3228 */
3229 if ((search & S_DOUNTRUSTED) != 0) {
3230 num = sk_X509_num(ctx->chain);
3231 if (!ossl_assert(num == ctx->num_untrusted))
3232 goto int_err;
3233 curr = sk_X509_value(ctx->chain, num - 1);
3234 issuer = (X509_self_signed(curr, 0) > 0 || num > max_depth) ?
3235 NULL : find_issuer(ctx, sk_untrusted, curr);
3236 if (issuer == NULL) {
3237 /*
3238 * Once we have reached a self-signed cert or num > max_depth
3239 * or can't find an issuer in the untrusted list we stop looking
3240 * there and start looking only in the trust store if enabled.
3241 */
3242 search &= ~S_DOUNTRUSTED;
3243 if (may_trusted)
3244 search |= S_DOTRUSTED;
3245 continue;
3246 }
3247
3248 /* Drop this issuer from future consideration */
3249 (void)sk_X509_delete_ptr(sk_untrusted, issuer);
3250
3251 if (!X509_add_cert(ctx->chain, issuer, X509_ADD_FLAG_UP_REF))
3252 goto int_err;
3253
3254 ++ctx->num_untrusted;
3255
3256 /* Check for DANE-TA trust of the topmost untrusted certificate. */
3257 trust = check_dane_issuer(ctx, ctx->num_untrusted - 1);
3258 if (trust == X509_TRUST_TRUSTED || trust == X509_TRUST_REJECTED)
3259 break;
3260 }
3261 }
3262 sk_X509_free(sk_untrusted);
3263
3264 if (trust < 0) /* internal error */
3265 return trust;
3266
3267 /*
3268 * Last chance to make a trusted chain, either bare DANE-TA public-key
3269 * signers, or else direct leaf PKIX trust.
3270 */
3271 num = sk_X509_num(ctx->chain);
3272 if (num <= max_depth) {
3273 if (trust == X509_TRUST_UNTRUSTED && DANETLS_HAS_DANE_TA(dane))
3274 trust = check_dane_pkeys(ctx);
3275 if (trust == X509_TRUST_UNTRUSTED && num == ctx->num_untrusted)
3276 trust = check_trust(ctx, num);
3277 }
3278
3279 switch (trust) {
3280 case X509_TRUST_TRUSTED:
3281 return 1;
3282 case X509_TRUST_REJECTED:
3283 /* Callback already issued */
3284 return 0;
3285 case X509_TRUST_UNTRUSTED:
3286 default:
3287 switch(ctx->error) {
3288 case X509_V_ERR_ERROR_IN_CERT_NOT_BEFORE_FIELD:
3289 case X509_V_ERR_CERT_NOT_YET_VALID:
3290 case X509_V_ERR_ERROR_IN_CERT_NOT_AFTER_FIELD:
3291 case X509_V_ERR_CERT_HAS_EXPIRED:
3292 return 0; /* Callback already issued by ossl_x509_check_cert_time() */
3293 default: /* A preliminary error has become final */
3294 return verify_cb_cert(ctx, NULL, num - 1, ctx->error);
3295 case X509_V_OK:
3296 break;
3297 }
3298 CB_FAIL_IF(num > max_depth,
3299 ctx, NULL, num - 1, X509_V_ERR_CERT_CHAIN_TOO_LONG);
3300 CB_FAIL_IF(DANETLS_ENABLED(dane)
3301 && (!DANETLS_HAS_PKIX(dane) || dane->pdpth >= 0),
3302 ctx, NULL, num - 1, X509_V_ERR_DANE_NO_MATCH);
3303 if (X509_self_signed(sk_X509_value(ctx->chain, num - 1), 0) > 0)
3304 return verify_cb_cert(ctx, NULL, num - 1,
3305 num == 1
3306 ? X509_V_ERR_DEPTH_ZERO_SELF_SIGNED_CERT
3307 : X509_V_ERR_SELF_SIGNED_CERT_IN_CHAIN);
3308 return verify_cb_cert(ctx, NULL, num - 1,
3309 ctx->num_untrusted < num
3310 ? X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT
3311 : X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT_LOCALLY);
3312 }
3313
3314 int_err:
3315 ERR_raise(ERR_LIB_X509, ERR_R_INTERNAL_ERROR);
3316 ctx->error = X509_V_ERR_UNSPECIFIED;
3317 sk_X509_free(sk_untrusted);
3318 return -1;
3319
3320 memerr:
3321 ERR_raise(ERR_LIB_X509, ERR_R_MALLOC_FAILURE);
3322 ctx->error = X509_V_ERR_OUT_OF_MEM;
3323 sk_X509_free(sk_untrusted);
3324 return -1;
3325 }
3326
STACK_OF(X509)3327 STACK_OF(X509) *X509_build_chain(X509 *target, STACK_OF(X509) *certs,
3328 X509_STORE *store, int with_self_signed,
3329 OSSL_LIB_CTX *libctx, const char *propq)
3330 {
3331 int finish_chain = store != NULL;
3332 X509_STORE_CTX *ctx;
3333 int flags = X509_ADD_FLAG_UP_REF;
3334 STACK_OF(X509) *result = NULL;
3335
3336 if (target == NULL) {
3337 ERR_raise(ERR_LIB_X509, ERR_R_PASSED_NULL_PARAMETER);
3338 return NULL;
3339 }
3340
3341 if ((ctx = X509_STORE_CTX_new_ex(libctx, propq)) == NULL)
3342 return NULL;
3343 if (!X509_STORE_CTX_init(ctx, store, target, finish_chain ? certs : NULL))
3344 goto err;
3345 if (!finish_chain)
3346 X509_STORE_CTX_set0_trusted_stack(ctx, certs);
3347 if (!ossl_x509_add_cert_new(&ctx->chain, target, X509_ADD_FLAG_UP_REF)) {
3348 ctx->error = X509_V_ERR_OUT_OF_MEM;
3349 goto err;
3350 }
3351 ctx->num_untrusted = 1;
3352
3353 if (!build_chain(ctx) && finish_chain)
3354 goto err;
3355
3356 /* result list to store the up_ref'ed certificates */
3357 if (sk_X509_num(ctx->chain) > 1 && !with_self_signed)
3358 flags |= X509_ADD_FLAG_NO_SS;
3359 if (!ossl_x509_add_certs_new(&result, ctx->chain, flags)) {
3360 sk_X509_free(result);
3361 result = NULL;
3362 }
3363
3364 err:
3365 X509_STORE_CTX_free(ctx);
3366 return result;
3367 }
3368
3369 /*
3370 * note that there's a corresponding minbits_table in ssl/ssl_cert.c
3371 * in ssl_get_security_level_bits that's used for selection of DH parameters
3372 */
3373 static const int minbits_table[] = { 80, 112, 128, 192, 256 };
3374 static const int NUM_AUTH_LEVELS = OSSL_NELEM(minbits_table);
3375
3376 /*-
3377 * Check whether the public key of `cert` meets the security level of `ctx`.
3378 * Returns 1 on success, 0 otherwise.
3379 */
check_key_level(X509_STORE_CTX * ctx,X509 * cert)3380 static int check_key_level(X509_STORE_CTX *ctx, X509 *cert)
3381 {
3382 EVP_PKEY *pkey = X509_get0_pubkey(cert);
3383 int level = ctx->param->auth_level;
3384
3385 /*
3386 * At security level zero, return without checking for a supported public
3387 * key type. Some engines support key types not understood outside the
3388 * engine, and we only need to understand the key when enforcing a security
3389 * floor.
3390 */
3391 if (level <= 0)
3392 return 1;
3393
3394 /* Unsupported or malformed keys are not secure */
3395 if (pkey == NULL)
3396 return 0;
3397
3398 if (level > NUM_AUTH_LEVELS)
3399 level = NUM_AUTH_LEVELS;
3400
3401 return EVP_PKEY_get_security_bits(pkey) >= minbits_table[level - 1];
3402 }
3403
3404 /*-
3405 * Check whether the public key of ``cert`` does not use explicit params
3406 * for an elliptic curve.
3407 *
3408 * Returns 1 on success, 0 if check fails, -1 for other errors.
3409 */
check_curve(X509 * cert)3410 static int check_curve(X509 *cert)
3411 {
3412 EVP_PKEY *pkey = X509_get0_pubkey(cert);
3413
3414 /* Unsupported or malformed key */
3415 if (pkey == NULL)
3416 return -1;
3417
3418 if (EVP_PKEY_get_id(pkey) == EVP_PKEY_EC) {
3419 int ret, val;
3420
3421 ret = EVP_PKEY_get_int_param(pkey,
3422 OSSL_PKEY_PARAM_EC_DECODED_FROM_EXPLICIT_PARAMS,
3423 &val);
3424 return ret < 0 ? ret : !val;
3425 }
3426
3427 return 1;
3428 }
3429
3430 /*-
3431 * Check whether the signature digest algorithm of ``cert`` meets the security
3432 * level of ``ctx``. Should not be checked for trust anchors (whether
3433 * self-signed or otherwise).
3434 *
3435 * Returns 1 on success, 0 otherwise.
3436 */
check_sig_level(X509_STORE_CTX * ctx,X509 * cert)3437 static int check_sig_level(X509_STORE_CTX *ctx, X509 *cert)
3438 {
3439 int secbits = -1;
3440 int level = ctx->param->auth_level;
3441
3442 if (level <= 0)
3443 return 1;
3444 if (level > NUM_AUTH_LEVELS)
3445 level = NUM_AUTH_LEVELS;
3446
3447 if (!X509_get_signature_info(cert, NULL, NULL, &secbits, NULL))
3448 return 0;
3449
3450 return secbits >= minbits_table[level - 1];
3451 }
3452