1 | /* |
2 | * Copyright 1995-2018 The OpenSSL Project Authors. All Rights Reserved. |
3 | * |
4 | * Licensed under the Apache License 2.0 (the "License"). You may not use |
5 | * this file except in compliance with the License. You can obtain a copy |
6 | * in the file LICENSE in the source distribution or at |
7 | * https://www.openssl.org/source/license.html |
8 | */ |
9 | |
10 | #include <stdio.h> |
11 | #include <time.h> |
12 | #include <errno.h> |
13 | #include <limits.h> |
14 | |
15 | #include "crypto/ctype.h" |
16 | #include "internal/cryptlib.h" |
17 | #include <openssl/crypto.h> |
18 | #include <openssl/buffer.h> |
19 | #include <openssl/evp.h> |
20 | #include <openssl/asn1.h> |
21 | #include <openssl/x509.h> |
22 | #include <openssl/x509v3.h> |
23 | #include <openssl/objects.h> |
24 | #include "internal/dane.h" |
25 | #include "crypto/x509.h" |
26 | #include "x509_local.h" |
27 | |
28 | /* CRL score values */ |
29 | |
30 | /* No unhandled critical extensions */ |
31 | |
32 | #define CRL_SCORE_NOCRITICAL 0x100 |
33 | |
34 | /* certificate is within CRL scope */ |
35 | |
36 | #define CRL_SCORE_SCOPE 0x080 |
37 | |
38 | /* CRL times valid */ |
39 | |
40 | #define CRL_SCORE_TIME 0x040 |
41 | |
42 | /* Issuer name matches certificate */ |
43 | |
44 | #define CRL_SCORE_ISSUER_NAME 0x020 |
45 | |
46 | /* If this score or above CRL is probably valid */ |
47 | |
48 | #define CRL_SCORE_VALID (CRL_SCORE_NOCRITICAL|CRL_SCORE_TIME|CRL_SCORE_SCOPE) |
49 | |
50 | /* CRL issuer is certificate issuer */ |
51 | |
52 | #define CRL_SCORE_ISSUER_CERT 0x018 |
53 | |
54 | /* CRL issuer is on certificate path */ |
55 | |
56 | #define CRL_SCORE_SAME_PATH 0x008 |
57 | |
58 | /* CRL issuer matches CRL AKID */ |
59 | |
60 | #define CRL_SCORE_AKID 0x004 |
61 | |
62 | /* Have a delta CRL with valid times */ |
63 | |
64 | #define CRL_SCORE_TIME_DELTA 0x002 |
65 | |
66 | static int build_chain(X509_STORE_CTX *ctx); |
67 | static int verify_chain(X509_STORE_CTX *ctx); |
68 | static int dane_verify(X509_STORE_CTX *ctx); |
69 | static int null_callback(int ok, X509_STORE_CTX *e); |
70 | static int check_issued(X509_STORE_CTX *ctx, X509 *x, X509 *issuer); |
71 | static X509 *find_issuer(X509_STORE_CTX *ctx, STACK_OF(X509) *sk, X509 *x); |
72 | static int check_chain_extensions(X509_STORE_CTX *ctx); |
73 | static int check_name_constraints(X509_STORE_CTX *ctx); |
74 | static int check_id(X509_STORE_CTX *ctx); |
75 | static int check_trust(X509_STORE_CTX *ctx, int num_untrusted); |
76 | static int check_revocation(X509_STORE_CTX *ctx); |
77 | static int check_cert(X509_STORE_CTX *ctx); |
78 | static int check_policy(X509_STORE_CTX *ctx); |
79 | static int get_issuer_sk(X509 **issuer, X509_STORE_CTX *ctx, X509 *x); |
80 | static int check_dane_issuer(X509_STORE_CTX *ctx, int depth); |
81 | static int check_key_level(X509_STORE_CTX *ctx, X509 *cert); |
82 | static int check_sig_level(X509_STORE_CTX *ctx, X509 *cert); |
83 | |
84 | static int get_crl_score(X509_STORE_CTX *ctx, X509 **pissuer, |
85 | unsigned int *preasons, X509_CRL *crl, X509 *x); |
86 | static int get_crl_delta(X509_STORE_CTX *ctx, |
87 | X509_CRL **pcrl, X509_CRL **pdcrl, X509 *x); |
88 | static void get_delta_sk(X509_STORE_CTX *ctx, X509_CRL **dcrl, |
89 | int *pcrl_score, X509_CRL *base, |
90 | STACK_OF(X509_CRL) *crls); |
91 | static void crl_akid_check(X509_STORE_CTX *ctx, X509_CRL *crl, X509 **pissuer, |
92 | int *pcrl_score); |
93 | static int crl_crldp_check(X509 *x, X509_CRL *crl, int crl_score, |
94 | unsigned int *preasons); |
95 | static int check_crl_path(X509_STORE_CTX *ctx, X509 *x); |
96 | static int check_crl_chain(X509_STORE_CTX *ctx, |
97 | STACK_OF(X509) *cert_path, |
98 | STACK_OF(X509) *crl_path); |
99 | |
100 | static int internal_verify(X509_STORE_CTX *ctx); |
101 | |
102 | static int null_callback(int ok, X509_STORE_CTX *e) |
103 | { |
104 | return ok; |
105 | } |
106 | |
107 | /* Return 1 is a certificate is self signed */ |
108 | static int cert_self_signed(X509 *x) |
109 | { |
110 | /* |
111 | * FIXME: x509v3_cache_extensions() needs to detect more failures and not |
112 | * set EXFLAG_SET when that happens. Especially, if the failures are |
113 | * parse errors, rather than memory pressure! |
114 | */ |
115 | X509_check_purpose(x, -1, 0); |
116 | if (x->ex_flags & EXFLAG_SS) |
117 | return 1; |
118 | else |
119 | return 0; |
120 | } |
121 | |
122 | /* Given a certificate try and find an exact match in the store */ |
123 | |
124 | static X509 *lookup_cert_match(X509_STORE_CTX *ctx, X509 *x) |
125 | { |
126 | STACK_OF(X509) *certs; |
127 | X509 *xtmp = NULL; |
128 | int i; |
129 | /* Lookup all certs with matching subject name */ |
130 | certs = ctx->lookup_certs(ctx, X509_get_subject_name(x)); |
131 | if (certs == NULL) |
132 | return NULL; |
133 | /* Look for exact match */ |
134 | for (i = 0; i < sk_X509_num(certs); i++) { |
135 | xtmp = sk_X509_value(certs, i); |
136 | if (!X509_cmp(xtmp, x)) |
137 | break; |
138 | } |
139 | if (i < sk_X509_num(certs)) |
140 | X509_up_ref(xtmp); |
141 | else |
142 | xtmp = NULL; |
143 | sk_X509_pop_free(certs, X509_free); |
144 | return xtmp; |
145 | } |
146 | |
147 | /*- |
148 | * Inform the verify callback of an error. |
149 | * If B<x> is not NULL it is the error cert, otherwise use the chain cert at |
150 | * B<depth>. |
151 | * If B<err> is not X509_V_OK, that's the error value, otherwise leave |
152 | * unchanged (presumably set by the caller). |
153 | * |
154 | * Returns 0 to abort verification with an error, non-zero to continue. |
155 | */ |
156 | static int verify_cb_cert(X509_STORE_CTX *ctx, X509 *x, int depth, int err) |
157 | { |
158 | ctx->error_depth = depth; |
159 | ctx->current_cert = (x != NULL) ? x : sk_X509_value(ctx->chain, depth); |
160 | if (err != X509_V_OK) |
161 | ctx->error = err; |
162 | return ctx->verify_cb(0, ctx); |
163 | } |
164 | |
165 | /*- |
166 | * Inform the verify callback of an error, CRL-specific variant. Here, the |
167 | * error depth and certificate are already set, we just specify the error |
168 | * number. |
169 | * |
170 | * Returns 0 to abort verification with an error, non-zero to continue. |
171 | */ |
172 | static int verify_cb_crl(X509_STORE_CTX *ctx, int err) |
173 | { |
174 | ctx->error = err; |
175 | return ctx->verify_cb(0, ctx); |
176 | } |
177 | |
178 | static int check_auth_level(X509_STORE_CTX *ctx) |
179 | { |
180 | int i; |
181 | int num = sk_X509_num(ctx->chain); |
182 | |
183 | if (ctx->param->auth_level <= 0) |
184 | return 1; |
185 | |
186 | for (i = 0; i < num; ++i) { |
187 | X509 *cert = sk_X509_value(ctx->chain, i); |
188 | |
189 | /* |
190 | * We've already checked the security of the leaf key, so here we only |
191 | * check the security of issuer keys. |
192 | */ |
193 | if (i > 0 && !check_key_level(ctx, cert) && |
194 | verify_cb_cert(ctx, cert, i, X509_V_ERR_CA_KEY_TOO_SMALL) == 0) |
195 | return 0; |
196 | /* |
197 | * We also check the signature algorithm security of all certificates |
198 | * except those of the trust anchor at index num-1. |
199 | */ |
200 | if (i < num - 1 && !check_sig_level(ctx, cert) && |
201 | verify_cb_cert(ctx, cert, i, X509_V_ERR_CA_MD_TOO_WEAK) == 0) |
202 | return 0; |
203 | } |
204 | return 1; |
205 | } |
206 | |
207 | static int verify_chain(X509_STORE_CTX *ctx) |
208 | { |
209 | int err; |
210 | int ok; |
211 | |
212 | /* |
213 | * Before either returning with an error, or continuing with CRL checks, |
214 | * instantiate chain public key parameters. |
215 | */ |
216 | if ((ok = build_chain(ctx)) == 0 || |
217 | (ok = check_chain_extensions(ctx)) == 0 || |
218 | (ok = check_auth_level(ctx)) == 0 || |
219 | (ok = check_id(ctx)) == 0 || 1) |
220 | X509_get_pubkey_parameters(NULL, ctx->chain); |
221 | if (ok == 0 || (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 | if (err != X509_V_OK) { |
227 | if ((ok = verify_cb_cert(ctx, NULL, ctx->error_depth, err)) == 0) |
228 | return ok; |
229 | } |
230 | |
231 | /* Verify chain signatures and expiration times */ |
232 | ok = (ctx->verify != NULL) ? ctx->verify(ctx) : internal_verify(ctx); |
233 | if (!ok) |
234 | return ok; |
235 | |
236 | if ((ok = check_name_constraints(ctx)) == 0) |
237 | return ok; |
238 | |
239 | #ifndef OPENSSL_NO_RFC3779 |
240 | /* RFC 3779 path validation, now that CRL check has been done */ |
241 | if ((ok = X509v3_asid_validate_path(ctx)) == 0) |
242 | return ok; |
243 | if ((ok = X509v3_addr_validate_path(ctx)) == 0) |
244 | return ok; |
245 | #endif |
246 | |
247 | /* If we get this far evaluate policies */ |
248 | if (ctx->param->flags & X509_V_FLAG_POLICY_CHECK) |
249 | ok = ctx->check_policy(ctx); |
250 | return ok; |
251 | } |
252 | |
253 | int X509_verify_cert(X509_STORE_CTX *ctx) |
254 | { |
255 | SSL_DANE *dane = ctx->dane; |
256 | int ret; |
257 | |
258 | if (ctx->cert == NULL) { |
259 | X509err(X509_F_X509_VERIFY_CERT, X509_R_NO_CERT_SET_FOR_US_TO_VERIFY); |
260 | ctx->error = X509_V_ERR_INVALID_CALL; |
261 | return -1; |
262 | } |
263 | |
264 | if (ctx->chain != NULL) { |
265 | /* |
266 | * This X509_STORE_CTX has already been used to verify a cert. We |
267 | * cannot do another one. |
268 | */ |
269 | X509err(X509_F_X509_VERIFY_CERT, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED); |
270 | ctx->error = X509_V_ERR_INVALID_CALL; |
271 | return -1; |
272 | } |
273 | |
274 | /* |
275 | * first we make sure the chain we are going to build is present and that |
276 | * the first entry is in place |
277 | */ |
278 | if (((ctx->chain = sk_X509_new_null()) == NULL) || |
279 | (!sk_X509_push(ctx->chain, ctx->cert))) { |
280 | X509err(X509_F_X509_VERIFY_CERT, ERR_R_MALLOC_FAILURE); |
281 | ctx->error = X509_V_ERR_OUT_OF_MEM; |
282 | return -1; |
283 | } |
284 | X509_up_ref(ctx->cert); |
285 | ctx->num_untrusted = 1; |
286 | |
287 | /* If the peer's public key is too weak, we can stop early. */ |
288 | if (!check_key_level(ctx, ctx->cert) && |
289 | !verify_cb_cert(ctx, ctx->cert, 0, X509_V_ERR_EE_KEY_TOO_SMALL)) |
290 | return 0; |
291 | |
292 | if (DANETLS_ENABLED(dane)) |
293 | ret = dane_verify(ctx); |
294 | else |
295 | ret = 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 | |
307 | /* |
308 | * Given a STACK_OF(X509) find the issuer of cert (if any) |
309 | */ |
310 | static X509 *find_issuer(X509_STORE_CTX *ctx, STACK_OF(X509) *sk, X509 *x) |
311 | { |
312 | int i; |
313 | X509 *issuer, *rv = NULL; |
314 | |
315 | for (i = 0; i < sk_X509_num(sk); i++) { |
316 | issuer = sk_X509_value(sk, i); |
317 | if (ctx->check_issued(ctx, x, issuer)) { |
318 | rv = issuer; |
319 | if (x509_check_cert_time(ctx, rv, -1)) |
320 | break; |
321 | } |
322 | } |
323 | return rv; |
324 | } |
325 | |
326 | /* Given a possible certificate and issuer check them */ |
327 | |
328 | static int check_issued(X509_STORE_CTX *ctx, X509 *x, X509 *issuer) |
329 | { |
330 | int ret; |
331 | if (x == issuer) |
332 | return cert_self_signed(x); |
333 | ret = X509_check_issued(issuer, x); |
334 | if (ret == X509_V_OK) { |
335 | int i; |
336 | X509 *ch; |
337 | /* Special case: single self signed certificate */ |
338 | if (cert_self_signed(x) && sk_X509_num(ctx->chain) == 1) |
339 | return 1; |
340 | for (i = 0; i < sk_X509_num(ctx->chain); i++) { |
341 | ch = sk_X509_value(ctx->chain, i); |
342 | if (ch == issuer || !X509_cmp(ch, issuer)) { |
343 | ret = X509_V_ERR_PATH_LOOP; |
344 | break; |
345 | } |
346 | } |
347 | } |
348 | |
349 | return (ret == X509_V_OK); |
350 | } |
351 | |
352 | /* Alternative lookup method: look from a STACK stored in other_ctx */ |
353 | |
354 | static int get_issuer_sk(X509 **issuer, X509_STORE_CTX *ctx, X509 *x) |
355 | { |
356 | *issuer = find_issuer(ctx, ctx->other_ctx, x); |
357 | if (*issuer) { |
358 | X509_up_ref(*issuer); |
359 | return 1; |
360 | } else |
361 | return 0; |
362 | } |
363 | |
364 | static STACK_OF(X509) *lookup_certs_sk(X509_STORE_CTX *ctx, X509_NAME *nm) |
365 | { |
366 | STACK_OF(X509) *sk = NULL; |
367 | X509 *x; |
368 | int i; |
369 | |
370 | for (i = 0; i < sk_X509_num(ctx->other_ctx); i++) { |
371 | x = sk_X509_value(ctx->other_ctx, i); |
372 | if (X509_NAME_cmp(nm, X509_get_subject_name(x)) == 0) { |
373 | if (sk == NULL) |
374 | sk = sk_X509_new_null(); |
375 | if (sk == NULL || sk_X509_push(sk, x) == 0) { |
376 | sk_X509_pop_free(sk, X509_free); |
377 | X509err(X509_F_LOOKUP_CERTS_SK, ERR_R_MALLOC_FAILURE); |
378 | ctx->error = X509_V_ERR_OUT_OF_MEM; |
379 | return NULL; |
380 | } |
381 | X509_up_ref(x); |
382 | } |
383 | } |
384 | return sk; |
385 | } |
386 | |
387 | /* |
388 | * Check EE or CA certificate purpose. For trusted certificates explicit local |
389 | * auxiliary trust can be used to override EKU-restrictions. |
390 | */ |
391 | static int check_purpose(X509_STORE_CTX *ctx, X509 *x, int purpose, int depth, |
392 | int must_be_ca) |
393 | { |
394 | int tr_ok = X509_TRUST_UNTRUSTED; |
395 | |
396 | /* |
397 | * For trusted certificates we want to see whether any auxiliary trust |
398 | * settings trump the purpose constraints. |
399 | * |
400 | * This is complicated by the fact that the trust ordinals in |
401 | * ctx->param->trust are entirely independent of the purpose ordinals in |
402 | * ctx->param->purpose! |
403 | * |
404 | * What connects them is their mutual initialization via calls from |
405 | * X509_STORE_CTX_set_default() into X509_VERIFY_PARAM_lookup() which sets |
406 | * related values of both param->trust and param->purpose. It is however |
407 | * typically possible to infer associated trust values from a purpose value |
408 | * via the X509_PURPOSE API. |
409 | * |
410 | * Therefore, we can only check for trust overrides when the purpose we're |
411 | * checking is the same as ctx->param->purpose and ctx->param->trust is |
412 | * also set. |
413 | */ |
414 | if (depth >= ctx->num_untrusted && purpose == ctx->param->purpose) |
415 | tr_ok = X509_check_trust(x, ctx->param->trust, X509_TRUST_NO_SS_COMPAT); |
416 | |
417 | switch (tr_ok) { |
418 | case X509_TRUST_TRUSTED: |
419 | return 1; |
420 | case X509_TRUST_REJECTED: |
421 | break; |
422 | default: |
423 | switch (X509_check_purpose(x, purpose, must_be_ca > 0)) { |
424 | case 1: |
425 | return 1; |
426 | case 0: |
427 | break; |
428 | default: |
429 | if ((ctx->param->flags & X509_V_FLAG_X509_STRICT) == 0) |
430 | return 1; |
431 | } |
432 | break; |
433 | } |
434 | |
435 | return verify_cb_cert(ctx, x, depth, X509_V_ERR_INVALID_PURPOSE); |
436 | } |
437 | |
438 | /* |
439 | * Check a certificate chains extensions for consistency with the supplied |
440 | * purpose |
441 | */ |
442 | |
443 | static int check_chain_extensions(X509_STORE_CTX *ctx) |
444 | { |
445 | int i, must_be_ca, plen = 0; |
446 | X509 *x; |
447 | int proxy_path_length = 0; |
448 | int purpose; |
449 | int allow_proxy_certs; |
450 | int num = sk_X509_num(ctx->chain); |
451 | |
452 | /*- |
453 | * must_be_ca can have 1 of 3 values: |
454 | * -1: we accept both CA and non-CA certificates, to allow direct |
455 | * use of self-signed certificates (which are marked as CA). |
456 | * 0: we only accept non-CA certificates. This is currently not |
457 | * used, but the possibility is present for future extensions. |
458 | * 1: we only accept CA certificates. This is currently used for |
459 | * all certificates in the chain except the leaf certificate. |
460 | */ |
461 | must_be_ca = -1; |
462 | |
463 | /* CRL path validation */ |
464 | if (ctx->parent) { |
465 | allow_proxy_certs = 0; |
466 | purpose = X509_PURPOSE_CRL_SIGN; |
467 | } else { |
468 | allow_proxy_certs = |
469 | ! !(ctx->param->flags & X509_V_FLAG_ALLOW_PROXY_CERTS); |
470 | purpose = ctx->param->purpose; |
471 | } |
472 | |
473 | for (i = 0; i < num; i++) { |
474 | int ret; |
475 | x = sk_X509_value(ctx->chain, i); |
476 | if (!(ctx->param->flags & X509_V_FLAG_IGNORE_CRITICAL) |
477 | && (x->ex_flags & EXFLAG_CRITICAL)) { |
478 | if (!verify_cb_cert(ctx, x, i, |
479 | X509_V_ERR_UNHANDLED_CRITICAL_EXTENSION)) |
480 | return 0; |
481 | } |
482 | if (!allow_proxy_certs && (x->ex_flags & EXFLAG_PROXY)) { |
483 | if (!verify_cb_cert(ctx, x, i, |
484 | X509_V_ERR_PROXY_CERTIFICATES_NOT_ALLOWED)) |
485 | return 0; |
486 | } |
487 | ret = X509_check_ca(x); |
488 | switch (must_be_ca) { |
489 | case -1: |
490 | if ((ctx->param->flags & X509_V_FLAG_X509_STRICT) |
491 | && (ret != 1) && (ret != 0)) { |
492 | ret = 0; |
493 | ctx->error = X509_V_ERR_INVALID_CA; |
494 | } else |
495 | ret = 1; |
496 | break; |
497 | case 0: |
498 | if (ret != 0) { |
499 | ret = 0; |
500 | ctx->error = X509_V_ERR_INVALID_NON_CA; |
501 | } else |
502 | ret = 1; |
503 | break; |
504 | default: |
505 | /* X509_V_FLAG_X509_STRICT is implicit for intermediate CAs */ |
506 | if ((ret == 0) |
507 | || ((i + 1 < num || ctx->param->flags & X509_V_FLAG_X509_STRICT) |
508 | && (ret != 1))) { |
509 | ret = 0; |
510 | ctx->error = X509_V_ERR_INVALID_CA; |
511 | } else |
512 | ret = 1; |
513 | break; |
514 | } |
515 | if (ret == 0 && !verify_cb_cert(ctx, x, i, X509_V_OK)) |
516 | return 0; |
517 | /* check_purpose() makes the callback as needed */ |
518 | if (purpose > 0 && !check_purpose(ctx, x, purpose, i, must_be_ca)) |
519 | return 0; |
520 | /* Check pathlen */ |
521 | if ((i > 1) && (x->ex_pathlen != -1) |
522 | && (plen > (x->ex_pathlen + proxy_path_length))) { |
523 | if (!verify_cb_cert(ctx, x, i, X509_V_ERR_PATH_LENGTH_EXCEEDED)) |
524 | return 0; |
525 | } |
526 | /* Increment path length if not a self issued intermediate CA */ |
527 | if (i > 0 && (x->ex_flags & EXFLAG_SI) == 0) |
528 | plen++; |
529 | /* |
530 | * If this certificate is a proxy certificate, the next certificate |
531 | * must be another proxy certificate or a EE certificate. If not, |
532 | * the next certificate must be a CA certificate. |
533 | */ |
534 | if (x->ex_flags & EXFLAG_PROXY) { |
535 | /* |
536 | * RFC3820, 4.1.3 (b)(1) stipulates that if pCPathLengthConstraint |
537 | * is less than max_path_length, the former should be copied to |
538 | * the latter, and 4.1.4 (a) stipulates that max_path_length |
539 | * should be verified to be larger than zero and decrement it. |
540 | * |
541 | * Because we're checking the certs in the reverse order, we start |
542 | * with verifying that proxy_path_length isn't larger than pcPLC, |
543 | * and copy the latter to the former if it is, and finally, |
544 | * increment proxy_path_length. |
545 | */ |
546 | if (x->ex_pcpathlen != -1) { |
547 | if (proxy_path_length > x->ex_pcpathlen) { |
548 | if (!verify_cb_cert(ctx, x, i, |
549 | X509_V_ERR_PROXY_PATH_LENGTH_EXCEEDED)) |
550 | return 0; |
551 | } |
552 | proxy_path_length = x->ex_pcpathlen; |
553 | } |
554 | proxy_path_length++; |
555 | must_be_ca = 0; |
556 | } else |
557 | must_be_ca = 1; |
558 | } |
559 | return 1; |
560 | } |
561 | |
562 | static int has_san_id(X509 *x, int gtype) |
563 | { |
564 | int i; |
565 | int ret = 0; |
566 | GENERAL_NAMES *gs = X509_get_ext_d2i(x, NID_subject_alt_name, NULL, NULL); |
567 | |
568 | if (gs == NULL) |
569 | return 0; |
570 | |
571 | for (i = 0; i < sk_GENERAL_NAME_num(gs); i++) { |
572 | GENERAL_NAME *g = sk_GENERAL_NAME_value(gs, i); |
573 | |
574 | if (g->type == gtype) { |
575 | ret = 1; |
576 | break; |
577 | } |
578 | } |
579 | GENERAL_NAMES_free(gs); |
580 | return ret; |
581 | } |
582 | |
583 | static int check_name_constraints(X509_STORE_CTX *ctx) |
584 | { |
585 | int i; |
586 | |
587 | /* Check name constraints for all certificates */ |
588 | for (i = sk_X509_num(ctx->chain) - 1; i >= 0; i--) { |
589 | X509 *x = sk_X509_value(ctx->chain, i); |
590 | int j; |
591 | |
592 | /* Ignore self issued certs unless last in chain */ |
593 | if (i && (x->ex_flags & EXFLAG_SI)) |
594 | continue; |
595 | |
596 | /* |
597 | * Proxy certificates policy has an extra constraint, where the |
598 | * certificate subject MUST be the issuer with a single CN entry |
599 | * added. |
600 | * (RFC 3820: 3.4, 4.1.3 (a)(4)) |
601 | */ |
602 | if (x->ex_flags & EXFLAG_PROXY) { |
603 | X509_NAME *tmpsubject = X509_get_subject_name(x); |
604 | X509_NAME *tmpissuer = X509_get_issuer_name(x); |
605 | X509_NAME_ENTRY *tmpentry = NULL; |
606 | int last_object_nid = 0; |
607 | int err = X509_V_OK; |
608 | int last_object_loc = X509_NAME_entry_count(tmpsubject) - 1; |
609 | |
610 | /* Check that there are at least two RDNs */ |
611 | if (last_object_loc < 1) { |
612 | err = X509_V_ERR_PROXY_SUBJECT_NAME_VIOLATION; |
613 | goto proxy_name_done; |
614 | } |
615 | |
616 | /* |
617 | * Check that there is exactly one more RDN in subject as |
618 | * there is in issuer. |
619 | */ |
620 | if (X509_NAME_entry_count(tmpsubject) |
621 | != X509_NAME_entry_count(tmpissuer) + 1) { |
622 | err = X509_V_ERR_PROXY_SUBJECT_NAME_VIOLATION; |
623 | goto proxy_name_done; |
624 | } |
625 | |
626 | /* |
627 | * Check that the last subject component isn't part of a |
628 | * multivalued RDN |
629 | */ |
630 | if (X509_NAME_ENTRY_set(X509_NAME_get_entry(tmpsubject, |
631 | last_object_loc)) |
632 | == X509_NAME_ENTRY_set(X509_NAME_get_entry(tmpsubject, |
633 | last_object_loc - 1))) { |
634 | err = X509_V_ERR_PROXY_SUBJECT_NAME_VIOLATION; |
635 | goto proxy_name_done; |
636 | } |
637 | |
638 | /* |
639 | * Check that the last subject RDN is a commonName, and that |
640 | * all the previous RDNs match the issuer exactly |
641 | */ |
642 | tmpsubject = X509_NAME_dup(tmpsubject); |
643 | if (tmpsubject == NULL) { |
644 | X509err(X509_F_CHECK_NAME_CONSTRAINTS, ERR_R_MALLOC_FAILURE); |
645 | ctx->error = X509_V_ERR_OUT_OF_MEM; |
646 | return 0; |
647 | } |
648 | |
649 | tmpentry = |
650 | X509_NAME_delete_entry(tmpsubject, last_object_loc); |
651 | last_object_nid = |
652 | OBJ_obj2nid(X509_NAME_ENTRY_get_object(tmpentry)); |
653 | |
654 | if (last_object_nid != NID_commonName |
655 | || X509_NAME_cmp(tmpsubject, tmpissuer) != 0) { |
656 | err = X509_V_ERR_PROXY_SUBJECT_NAME_VIOLATION; |
657 | } |
658 | |
659 | X509_NAME_ENTRY_free(tmpentry); |
660 | X509_NAME_free(tmpsubject); |
661 | |
662 | proxy_name_done: |
663 | if (err != X509_V_OK |
664 | && !verify_cb_cert(ctx, x, i, err)) |
665 | return 0; |
666 | } |
667 | |
668 | /* |
669 | * Check against constraints for all certificates higher in chain |
670 | * including trust anchor. Trust anchor not strictly speaking needed |
671 | * but if it includes constraints it is to be assumed it expects them |
672 | * to be obeyed. |
673 | */ |
674 | for (j = sk_X509_num(ctx->chain) - 1; j > i; j--) { |
675 | NAME_CONSTRAINTS *nc = sk_X509_value(ctx->chain, j)->nc; |
676 | |
677 | if (nc) { |
678 | int rv = NAME_CONSTRAINTS_check(x, nc); |
679 | |
680 | /* If EE certificate check commonName too */ |
681 | if (rv == X509_V_OK && i == 0 |
682 | && (ctx->param->hostflags |
683 | & X509_CHECK_FLAG_NEVER_CHECK_SUBJECT) == 0 |
684 | && ((ctx->param->hostflags |
685 | & X509_CHECK_FLAG_ALWAYS_CHECK_SUBJECT) != 0 |
686 | || !has_san_id(x, GEN_DNS))) |
687 | rv = NAME_CONSTRAINTS_check_CN(x, nc); |
688 | |
689 | switch (rv) { |
690 | case X509_V_OK: |
691 | break; |
692 | case X509_V_ERR_OUT_OF_MEM: |
693 | return 0; |
694 | default: |
695 | if (!verify_cb_cert(ctx, x, i, rv)) |
696 | return 0; |
697 | break; |
698 | } |
699 | } |
700 | } |
701 | } |
702 | return 1; |
703 | } |
704 | |
705 | static int check_id_error(X509_STORE_CTX *ctx, int errcode) |
706 | { |
707 | return verify_cb_cert(ctx, ctx->cert, 0, errcode); |
708 | } |
709 | |
710 | static int check_hosts(X509 *x, X509_VERIFY_PARAM *vpm) |
711 | { |
712 | int i; |
713 | int n = sk_OPENSSL_STRING_num(vpm->hosts); |
714 | char *name; |
715 | |
716 | if (vpm->peername != NULL) { |
717 | OPENSSL_free(vpm->peername); |
718 | vpm->peername = NULL; |
719 | } |
720 | for (i = 0; i < n; ++i) { |
721 | name = sk_OPENSSL_STRING_value(vpm->hosts, i); |
722 | if (X509_check_host(x, name, 0, vpm->hostflags, &vpm->peername) > 0) |
723 | return 1; |
724 | } |
725 | return n == 0; |
726 | } |
727 | |
728 | static int check_id(X509_STORE_CTX *ctx) |
729 | { |
730 | X509_VERIFY_PARAM *vpm = ctx->param; |
731 | X509 *x = ctx->cert; |
732 | if (vpm->hosts && check_hosts(x, vpm) <= 0) { |
733 | if (!check_id_error(ctx, X509_V_ERR_HOSTNAME_MISMATCH)) |
734 | return 0; |
735 | } |
736 | if (vpm->email && X509_check_email(x, vpm->email, vpm->emaillen, 0) <= 0) { |
737 | if (!check_id_error(ctx, X509_V_ERR_EMAIL_MISMATCH)) |
738 | return 0; |
739 | } |
740 | if (vpm->ip && X509_check_ip(x, vpm->ip, vpm->iplen, 0) <= 0) { |
741 | if (!check_id_error(ctx, X509_V_ERR_IP_ADDRESS_MISMATCH)) |
742 | return 0; |
743 | } |
744 | return 1; |
745 | } |
746 | |
747 | static int check_trust(X509_STORE_CTX *ctx, int num_untrusted) |
748 | { |
749 | int i; |
750 | X509 *x = NULL; |
751 | X509 *mx; |
752 | SSL_DANE *dane = ctx->dane; |
753 | int num = sk_X509_num(ctx->chain); |
754 | int trust; |
755 | |
756 | /* |
757 | * Check for a DANE issuer at depth 1 or greater, if it is a DANE-TA(2) |
758 | * match, we're done, otherwise we'll merely record the match depth. |
759 | */ |
760 | if (DANETLS_HAS_TA(dane) && num_untrusted > 0 && num_untrusted < num) { |
761 | switch (trust = check_dane_issuer(ctx, num_untrusted)) { |
762 | case X509_TRUST_TRUSTED: |
763 | case X509_TRUST_REJECTED: |
764 | return trust; |
765 | } |
766 | } |
767 | |
768 | /* |
769 | * Check trusted certificates in chain at depth num_untrusted and up. |
770 | * Note, that depths 0..num_untrusted-1 may also contain trusted |
771 | * certificates, but the caller is expected to have already checked those, |
772 | * and wants to incrementally check just any added since. |
773 | */ |
774 | for (i = num_untrusted; i < num; i++) { |
775 | x = sk_X509_value(ctx->chain, i); |
776 | trust = X509_check_trust(x, ctx->param->trust, 0); |
777 | /* If explicitly trusted return trusted */ |
778 | if (trust == X509_TRUST_TRUSTED) |
779 | goto trusted; |
780 | if (trust == X509_TRUST_REJECTED) |
781 | goto rejected; |
782 | } |
783 | |
784 | /* |
785 | * If we are looking at a trusted certificate, and accept partial chains, |
786 | * the chain is PKIX trusted. |
787 | */ |
788 | if (num_untrusted < num) { |
789 | if (ctx->param->flags & X509_V_FLAG_PARTIAL_CHAIN) |
790 | goto trusted; |
791 | return X509_TRUST_UNTRUSTED; |
792 | } |
793 | |
794 | if (num_untrusted == num && ctx->param->flags & X509_V_FLAG_PARTIAL_CHAIN) { |
795 | /* |
796 | * Last-resort call with no new trusted certificates, check the leaf |
797 | * for a direct trust store match. |
798 | */ |
799 | i = 0; |
800 | x = sk_X509_value(ctx->chain, i); |
801 | mx = lookup_cert_match(ctx, x); |
802 | if (!mx) |
803 | return X509_TRUST_UNTRUSTED; |
804 | |
805 | /* |
806 | * Check explicit auxiliary trust/reject settings. If none are set, |
807 | * we'll accept X509_TRUST_UNTRUSTED when not self-signed. |
808 | */ |
809 | trust = X509_check_trust(mx, ctx->param->trust, 0); |
810 | if (trust == X509_TRUST_REJECTED) { |
811 | X509_free(mx); |
812 | goto rejected; |
813 | } |
814 | |
815 | /* Replace leaf with trusted match */ |
816 | (void) sk_X509_set(ctx->chain, 0, mx); |
817 | X509_free(x); |
818 | ctx->num_untrusted = 0; |
819 | goto trusted; |
820 | } |
821 | |
822 | /* |
823 | * If no trusted certs in chain at all return untrusted and allow |
824 | * standard (no issuer cert) etc errors to be indicated. |
825 | */ |
826 | return X509_TRUST_UNTRUSTED; |
827 | |
828 | rejected: |
829 | if (!verify_cb_cert(ctx, x, i, X509_V_ERR_CERT_REJECTED)) |
830 | return X509_TRUST_REJECTED; |
831 | return X509_TRUST_UNTRUSTED; |
832 | |
833 | trusted: |
834 | if (!DANETLS_ENABLED(dane)) |
835 | return X509_TRUST_TRUSTED; |
836 | if (dane->pdpth < 0) |
837 | dane->pdpth = num_untrusted; |
838 | /* With DANE, PKIX alone is not trusted until we have both */ |
839 | if (dane->mdpth >= 0) |
840 | return X509_TRUST_TRUSTED; |
841 | return X509_TRUST_UNTRUSTED; |
842 | } |
843 | |
844 | static int check_revocation(X509_STORE_CTX *ctx) |
845 | { |
846 | int i = 0, last = 0, ok = 0; |
847 | if (!(ctx->param->flags & X509_V_FLAG_CRL_CHECK)) |
848 | return 1; |
849 | if (ctx->param->flags & X509_V_FLAG_CRL_CHECK_ALL) |
850 | last = sk_X509_num(ctx->chain) - 1; |
851 | else { |
852 | /* If checking CRL paths this isn't the EE certificate */ |
853 | if (ctx->parent) |
854 | return 1; |
855 | last = 0; |
856 | } |
857 | for (i = 0; i <= last; i++) { |
858 | ctx->error_depth = i; |
859 | ok = check_cert(ctx); |
860 | if (!ok) |
861 | return ok; |
862 | } |
863 | return 1; |
864 | } |
865 | |
866 | static int check_cert(X509_STORE_CTX *ctx) |
867 | { |
868 | X509_CRL *crl = NULL, *dcrl = NULL; |
869 | int ok = 0; |
870 | int cnum = ctx->error_depth; |
871 | X509 *x = sk_X509_value(ctx->chain, cnum); |
872 | |
873 | ctx->current_cert = x; |
874 | ctx->current_issuer = NULL; |
875 | ctx->current_crl_score = 0; |
876 | ctx->current_reasons = 0; |
877 | |
878 | if (x->ex_flags & EXFLAG_PROXY) |
879 | return 1; |
880 | |
881 | while (ctx->current_reasons != CRLDP_ALL_REASONS) { |
882 | unsigned int last_reasons = ctx->current_reasons; |
883 | |
884 | /* Try to retrieve relevant CRL */ |
885 | if (ctx->get_crl) |
886 | ok = ctx->get_crl(ctx, &crl, x); |
887 | else |
888 | ok = get_crl_delta(ctx, &crl, &dcrl, x); |
889 | /* |
890 | * If error looking up CRL, nothing we can do except notify callback |
891 | */ |
892 | if (!ok) { |
893 | ok = verify_cb_crl(ctx, X509_V_ERR_UNABLE_TO_GET_CRL); |
894 | goto done; |
895 | } |
896 | ctx->current_crl = crl; |
897 | ok = ctx->check_crl(ctx, crl); |
898 | if (!ok) |
899 | goto done; |
900 | |
901 | if (dcrl) { |
902 | ok = ctx->check_crl(ctx, dcrl); |
903 | if (!ok) |
904 | goto done; |
905 | ok = ctx->cert_crl(ctx, dcrl, x); |
906 | if (!ok) |
907 | goto done; |
908 | } else |
909 | ok = 1; |
910 | |
911 | /* Don't look in full CRL if delta reason is removefromCRL */ |
912 | if (ok != 2) { |
913 | ok = ctx->cert_crl(ctx, crl, x); |
914 | if (!ok) |
915 | goto done; |
916 | } |
917 | |
918 | X509_CRL_free(crl); |
919 | X509_CRL_free(dcrl); |
920 | crl = NULL; |
921 | dcrl = NULL; |
922 | /* |
923 | * If reasons not updated we won't get anywhere by another iteration, |
924 | * so exit loop. |
925 | */ |
926 | if (last_reasons == ctx->current_reasons) { |
927 | ok = verify_cb_crl(ctx, X509_V_ERR_UNABLE_TO_GET_CRL); |
928 | goto done; |
929 | } |
930 | } |
931 | done: |
932 | X509_CRL_free(crl); |
933 | X509_CRL_free(dcrl); |
934 | |
935 | ctx->current_crl = NULL; |
936 | return ok; |
937 | } |
938 | |
939 | /* Check CRL times against values in X509_STORE_CTX */ |
940 | |
941 | static int check_crl_time(X509_STORE_CTX *ctx, X509_CRL *crl, int notify) |
942 | { |
943 | time_t *ptime; |
944 | int i; |
945 | |
946 | if (notify) |
947 | ctx->current_crl = crl; |
948 | if (ctx->param->flags & X509_V_FLAG_USE_CHECK_TIME) |
949 | ptime = &ctx->param->check_time; |
950 | else if (ctx->param->flags & X509_V_FLAG_NO_CHECK_TIME) |
951 | return 1; |
952 | else |
953 | ptime = NULL; |
954 | |
955 | i = X509_cmp_time(X509_CRL_get0_lastUpdate(crl), ptime); |
956 | if (i == 0) { |
957 | if (!notify) |
958 | return 0; |
959 | if (!verify_cb_crl(ctx, X509_V_ERR_ERROR_IN_CRL_LAST_UPDATE_FIELD)) |
960 | return 0; |
961 | } |
962 | |
963 | if (i > 0) { |
964 | if (!notify) |
965 | return 0; |
966 | if (!verify_cb_crl(ctx, X509_V_ERR_CRL_NOT_YET_VALID)) |
967 | return 0; |
968 | } |
969 | |
970 | if (X509_CRL_get0_nextUpdate(crl)) { |
971 | i = X509_cmp_time(X509_CRL_get0_nextUpdate(crl), ptime); |
972 | |
973 | if (i == 0) { |
974 | if (!notify) |
975 | return 0; |
976 | if (!verify_cb_crl(ctx, X509_V_ERR_ERROR_IN_CRL_NEXT_UPDATE_FIELD)) |
977 | return 0; |
978 | } |
979 | /* Ignore expiry of base CRL is delta is valid */ |
980 | if ((i < 0) && !(ctx->current_crl_score & CRL_SCORE_TIME_DELTA)) { |
981 | if (!notify) |
982 | return 0; |
983 | if (!verify_cb_crl(ctx, X509_V_ERR_CRL_HAS_EXPIRED)) |
984 | return 0; |
985 | } |
986 | } |
987 | |
988 | if (notify) |
989 | ctx->current_crl = NULL; |
990 | |
991 | return 1; |
992 | } |
993 | |
994 | static int get_crl_sk(X509_STORE_CTX *ctx, X509_CRL **pcrl, X509_CRL **pdcrl, |
995 | X509 **pissuer, int *pscore, unsigned int *preasons, |
996 | STACK_OF(X509_CRL) *crls) |
997 | { |
998 | int i, crl_score, best_score = *pscore; |
999 | unsigned int reasons, best_reasons = 0; |
1000 | X509 *x = ctx->current_cert; |
1001 | X509_CRL *crl, *best_crl = NULL; |
1002 | X509 *crl_issuer = NULL, *best_crl_issuer = NULL; |
1003 | |
1004 | for (i = 0; i < sk_X509_CRL_num(crls); i++) { |
1005 | crl = sk_X509_CRL_value(crls, i); |
1006 | reasons = *preasons; |
1007 | crl_score = get_crl_score(ctx, &crl_issuer, &reasons, crl, x); |
1008 | if (crl_score < best_score || crl_score == 0) |
1009 | continue; |
1010 | /* If current CRL is equivalent use it if it is newer */ |
1011 | if (crl_score == best_score && best_crl != NULL) { |
1012 | int day, sec; |
1013 | if (ASN1_TIME_diff(&day, &sec, X509_CRL_get0_lastUpdate(best_crl), |
1014 | X509_CRL_get0_lastUpdate(crl)) == 0) |
1015 | continue; |
1016 | /* |
1017 | * ASN1_TIME_diff never returns inconsistent signs for |day| |
1018 | * and |sec|. |
1019 | */ |
1020 | if (day <= 0 && sec <= 0) |
1021 | continue; |
1022 | } |
1023 | best_crl = crl; |
1024 | best_crl_issuer = crl_issuer; |
1025 | best_score = crl_score; |
1026 | best_reasons = reasons; |
1027 | } |
1028 | |
1029 | if (best_crl) { |
1030 | X509_CRL_free(*pcrl); |
1031 | *pcrl = best_crl; |
1032 | *pissuer = best_crl_issuer; |
1033 | *pscore = best_score; |
1034 | *preasons = best_reasons; |
1035 | X509_CRL_up_ref(best_crl); |
1036 | X509_CRL_free(*pdcrl); |
1037 | *pdcrl = NULL; |
1038 | get_delta_sk(ctx, pdcrl, pscore, best_crl, crls); |
1039 | } |
1040 | |
1041 | if (best_score >= CRL_SCORE_VALID) |
1042 | return 1; |
1043 | |
1044 | return 0; |
1045 | } |
1046 | |
1047 | /* |
1048 | * Compare two CRL extensions for delta checking purposes. They should be |
1049 | * both present or both absent. If both present all fields must be identical. |
1050 | */ |
1051 | |
1052 | static int crl_extension_match(X509_CRL *a, X509_CRL *b, int nid) |
1053 | { |
1054 | ASN1_OCTET_STRING *exta, *extb; |
1055 | int i; |
1056 | i = X509_CRL_get_ext_by_NID(a, nid, -1); |
1057 | if (i >= 0) { |
1058 | /* Can't have multiple occurrences */ |
1059 | if (X509_CRL_get_ext_by_NID(a, nid, i) != -1) |
1060 | return 0; |
1061 | exta = X509_EXTENSION_get_data(X509_CRL_get_ext(a, i)); |
1062 | } else |
1063 | exta = NULL; |
1064 | |
1065 | i = X509_CRL_get_ext_by_NID(b, nid, -1); |
1066 | |
1067 | if (i >= 0) { |
1068 | |
1069 | if (X509_CRL_get_ext_by_NID(b, nid, i) != -1) |
1070 | return 0; |
1071 | extb = X509_EXTENSION_get_data(X509_CRL_get_ext(b, i)); |
1072 | } else |
1073 | extb = NULL; |
1074 | |
1075 | if (!exta && !extb) |
1076 | return 1; |
1077 | |
1078 | if (!exta || !extb) |
1079 | return 0; |
1080 | |
1081 | if (ASN1_OCTET_STRING_cmp(exta, extb)) |
1082 | return 0; |
1083 | |
1084 | return 1; |
1085 | } |
1086 | |
1087 | /* See if a base and delta are compatible */ |
1088 | |
1089 | static int check_delta_base(X509_CRL *delta, X509_CRL *base) |
1090 | { |
1091 | /* Delta CRL must be a delta */ |
1092 | if (!delta->base_crl_number) |
1093 | return 0; |
1094 | /* Base must have a CRL number */ |
1095 | if (!base->crl_number) |
1096 | return 0; |
1097 | /* Issuer names must match */ |
1098 | if (X509_NAME_cmp(X509_CRL_get_issuer(base), X509_CRL_get_issuer(delta))) |
1099 | return 0; |
1100 | /* AKID and IDP must match */ |
1101 | if (!crl_extension_match(delta, base, NID_authority_key_identifier)) |
1102 | return 0; |
1103 | if (!crl_extension_match(delta, base, NID_issuing_distribution_point)) |
1104 | return 0; |
1105 | /* Delta CRL base number must not exceed Full CRL number. */ |
1106 | if (ASN1_INTEGER_cmp(delta->base_crl_number, base->crl_number) > 0) |
1107 | return 0; |
1108 | /* Delta CRL number must exceed full CRL number */ |
1109 | if (ASN1_INTEGER_cmp(delta->crl_number, base->crl_number) > 0) |
1110 | return 1; |
1111 | return 0; |
1112 | } |
1113 | |
1114 | /* |
1115 | * For a given base CRL find a delta... maybe extend to delta scoring or |
1116 | * retrieve a chain of deltas... |
1117 | */ |
1118 | |
1119 | static void get_delta_sk(X509_STORE_CTX *ctx, X509_CRL **dcrl, int *pscore, |
1120 | X509_CRL *base, STACK_OF(X509_CRL) *crls) |
1121 | { |
1122 | X509_CRL *delta; |
1123 | int i; |
1124 | if (!(ctx->param->flags & X509_V_FLAG_USE_DELTAS)) |
1125 | return; |
1126 | if (!((ctx->current_cert->ex_flags | base->flags) & EXFLAG_FRESHEST)) |
1127 | return; |
1128 | for (i = 0; i < sk_X509_CRL_num(crls); i++) { |
1129 | delta = sk_X509_CRL_value(crls, i); |
1130 | if (check_delta_base(delta, base)) { |
1131 | if (check_crl_time(ctx, delta, 0)) |
1132 | *pscore |= CRL_SCORE_TIME_DELTA; |
1133 | X509_CRL_up_ref(delta); |
1134 | *dcrl = delta; |
1135 | return; |
1136 | } |
1137 | } |
1138 | *dcrl = NULL; |
1139 | } |
1140 | |
1141 | /* |
1142 | * For a given CRL return how suitable it is for the supplied certificate |
1143 | * 'x'. The return value is a mask of several criteria. If the issuer is not |
1144 | * the certificate issuer this is returned in *pissuer. The reasons mask is |
1145 | * also used to determine if the CRL is suitable: if no new reasons the CRL |
1146 | * is rejected, otherwise reasons is updated. |
1147 | */ |
1148 | |
1149 | static int get_crl_score(X509_STORE_CTX *ctx, X509 **pissuer, |
1150 | unsigned int *preasons, X509_CRL *crl, X509 *x) |
1151 | { |
1152 | |
1153 | int crl_score = 0; |
1154 | unsigned int tmp_reasons = *preasons, crl_reasons; |
1155 | |
1156 | /* First see if we can reject CRL straight away */ |
1157 | |
1158 | /* Invalid IDP cannot be processed */ |
1159 | if (crl->idp_flags & IDP_INVALID) |
1160 | return 0; |
1161 | /* Reason codes or indirect CRLs need extended CRL support */ |
1162 | if (!(ctx->param->flags & X509_V_FLAG_EXTENDED_CRL_SUPPORT)) { |
1163 | if (crl->idp_flags & (IDP_INDIRECT | IDP_REASONS)) |
1164 | return 0; |
1165 | } else if (crl->idp_flags & IDP_REASONS) { |
1166 | /* If no new reasons reject */ |
1167 | if (!(crl->idp_reasons & ~tmp_reasons)) |
1168 | return 0; |
1169 | } |
1170 | /* Don't process deltas at this stage */ |
1171 | else if (crl->base_crl_number) |
1172 | return 0; |
1173 | /* If issuer name doesn't match certificate need indirect CRL */ |
1174 | if (X509_NAME_cmp(X509_get_issuer_name(x), X509_CRL_get_issuer(crl))) { |
1175 | if (!(crl->idp_flags & IDP_INDIRECT)) |
1176 | return 0; |
1177 | } else |
1178 | crl_score |= CRL_SCORE_ISSUER_NAME; |
1179 | |
1180 | if (!(crl->flags & EXFLAG_CRITICAL)) |
1181 | crl_score |= CRL_SCORE_NOCRITICAL; |
1182 | |
1183 | /* Check expiry */ |
1184 | if (check_crl_time(ctx, crl, 0)) |
1185 | crl_score |= CRL_SCORE_TIME; |
1186 | |
1187 | /* Check authority key ID and locate certificate issuer */ |
1188 | crl_akid_check(ctx, crl, pissuer, &crl_score); |
1189 | |
1190 | /* If we can't locate certificate issuer at this point forget it */ |
1191 | |
1192 | if (!(crl_score & CRL_SCORE_AKID)) |
1193 | return 0; |
1194 | |
1195 | /* Check cert for matching CRL distribution points */ |
1196 | |
1197 | if (crl_crldp_check(x, crl, crl_score, &crl_reasons)) { |
1198 | /* If no new reasons reject */ |
1199 | if (!(crl_reasons & ~tmp_reasons)) |
1200 | return 0; |
1201 | tmp_reasons |= crl_reasons; |
1202 | crl_score |= CRL_SCORE_SCOPE; |
1203 | } |
1204 | |
1205 | *preasons = tmp_reasons; |
1206 | |
1207 | return crl_score; |
1208 | |
1209 | } |
1210 | |
1211 | static void crl_akid_check(X509_STORE_CTX *ctx, X509_CRL *crl, |
1212 | X509 **pissuer, int *pcrl_score) |
1213 | { |
1214 | X509 *crl_issuer = NULL; |
1215 | X509_NAME *cnm = X509_CRL_get_issuer(crl); |
1216 | int cidx = ctx->error_depth; |
1217 | int i; |
1218 | |
1219 | if (cidx != sk_X509_num(ctx->chain) - 1) |
1220 | cidx++; |
1221 | |
1222 | crl_issuer = sk_X509_value(ctx->chain, cidx); |
1223 | |
1224 | if (X509_check_akid(crl_issuer, crl->akid) == X509_V_OK) { |
1225 | if (*pcrl_score & CRL_SCORE_ISSUER_NAME) { |
1226 | *pcrl_score |= CRL_SCORE_AKID | CRL_SCORE_ISSUER_CERT; |
1227 | *pissuer = crl_issuer; |
1228 | return; |
1229 | } |
1230 | } |
1231 | |
1232 | for (cidx++; cidx < sk_X509_num(ctx->chain); cidx++) { |
1233 | crl_issuer = sk_X509_value(ctx->chain, cidx); |
1234 | if (X509_NAME_cmp(X509_get_subject_name(crl_issuer), cnm)) |
1235 | continue; |
1236 | if (X509_check_akid(crl_issuer, crl->akid) == X509_V_OK) { |
1237 | *pcrl_score |= CRL_SCORE_AKID | CRL_SCORE_SAME_PATH; |
1238 | *pissuer = crl_issuer; |
1239 | return; |
1240 | } |
1241 | } |
1242 | |
1243 | /* Anything else needs extended CRL support */ |
1244 | |
1245 | if (!(ctx->param->flags & X509_V_FLAG_EXTENDED_CRL_SUPPORT)) |
1246 | return; |
1247 | |
1248 | /* |
1249 | * Otherwise the CRL issuer is not on the path. Look for it in the set of |
1250 | * untrusted certificates. |
1251 | */ |
1252 | for (i = 0; i < sk_X509_num(ctx->untrusted); i++) { |
1253 | crl_issuer = sk_X509_value(ctx->untrusted, i); |
1254 | if (X509_NAME_cmp(X509_get_subject_name(crl_issuer), cnm)) |
1255 | continue; |
1256 | if (X509_check_akid(crl_issuer, crl->akid) == X509_V_OK) { |
1257 | *pissuer = crl_issuer; |
1258 | *pcrl_score |= CRL_SCORE_AKID; |
1259 | return; |
1260 | } |
1261 | } |
1262 | } |
1263 | |
1264 | /* |
1265 | * Check the path of a CRL issuer certificate. This creates a new |
1266 | * X509_STORE_CTX and populates it with most of the parameters from the |
1267 | * parent. This could be optimised somewhat since a lot of path checking will |
1268 | * be duplicated by the parent, but this will rarely be used in practice. |
1269 | */ |
1270 | |
1271 | static int check_crl_path(X509_STORE_CTX *ctx, X509 *x) |
1272 | { |
1273 | X509_STORE_CTX crl_ctx; |
1274 | int ret; |
1275 | |
1276 | /* Don't allow recursive CRL path validation */ |
1277 | if (ctx->parent) |
1278 | return 0; |
1279 | if (!X509_STORE_CTX_init(&crl_ctx, ctx->store, x, ctx->untrusted)) |
1280 | return -1; |
1281 | |
1282 | crl_ctx.crls = ctx->crls; |
1283 | /* Copy verify params across */ |
1284 | X509_STORE_CTX_set0_param(&crl_ctx, ctx->param); |
1285 | |
1286 | crl_ctx.parent = ctx; |
1287 | crl_ctx.verify_cb = ctx->verify_cb; |
1288 | |
1289 | /* Verify CRL issuer */ |
1290 | ret = X509_verify_cert(&crl_ctx); |
1291 | if (ret <= 0) |
1292 | goto err; |
1293 | |
1294 | /* Check chain is acceptable */ |
1295 | ret = check_crl_chain(ctx, ctx->chain, crl_ctx.chain); |
1296 | err: |
1297 | X509_STORE_CTX_cleanup(&crl_ctx); |
1298 | return ret; |
1299 | } |
1300 | |
1301 | /* |
1302 | * RFC3280 says nothing about the relationship between CRL path and |
1303 | * certificate path, which could lead to situations where a certificate could |
1304 | * be revoked or validated by a CA not authorised to do so. RFC5280 is more |
1305 | * strict and states that the two paths must end in the same trust anchor, |
1306 | * though some discussions remain... until this is resolved we use the |
1307 | * RFC5280 version |
1308 | */ |
1309 | |
1310 | static int check_crl_chain(X509_STORE_CTX *ctx, |
1311 | STACK_OF(X509) *cert_path, |
1312 | STACK_OF(X509) *crl_path) |
1313 | { |
1314 | X509 *cert_ta, *crl_ta; |
1315 | cert_ta = sk_X509_value(cert_path, sk_X509_num(cert_path) - 1); |
1316 | crl_ta = sk_X509_value(crl_path, sk_X509_num(crl_path) - 1); |
1317 | if (!X509_cmp(cert_ta, crl_ta)) |
1318 | return 1; |
1319 | return 0; |
1320 | } |
1321 | |
1322 | /*- |
1323 | * Check for match between two dist point names: three separate cases. |
1324 | * 1. Both are relative names and compare X509_NAME types. |
1325 | * 2. One full, one relative. Compare X509_NAME to GENERAL_NAMES. |
1326 | * 3. Both are full names and compare two GENERAL_NAMES. |
1327 | * 4. One is NULL: automatic match. |
1328 | */ |
1329 | |
1330 | static int idp_check_dp(DIST_POINT_NAME *a, DIST_POINT_NAME *b) |
1331 | { |
1332 | X509_NAME *nm = NULL; |
1333 | GENERAL_NAMES *gens = NULL; |
1334 | GENERAL_NAME *gena, *genb; |
1335 | int i, j; |
1336 | if (!a || !b) |
1337 | return 1; |
1338 | if (a->type == 1) { |
1339 | if (!a->dpname) |
1340 | return 0; |
1341 | /* Case 1: two X509_NAME */ |
1342 | if (b->type == 1) { |
1343 | if (!b->dpname) |
1344 | return 0; |
1345 | if (!X509_NAME_cmp(a->dpname, b->dpname)) |
1346 | return 1; |
1347 | else |
1348 | return 0; |
1349 | } |
1350 | /* Case 2: set name and GENERAL_NAMES appropriately */ |
1351 | nm = a->dpname; |
1352 | gens = b->name.fullname; |
1353 | } else if (b->type == 1) { |
1354 | if (!b->dpname) |
1355 | return 0; |
1356 | /* Case 2: set name and GENERAL_NAMES appropriately */ |
1357 | gens = a->name.fullname; |
1358 | nm = b->dpname; |
1359 | } |
1360 | |
1361 | /* Handle case 2 with one GENERAL_NAMES and one X509_NAME */ |
1362 | if (nm) { |
1363 | for (i = 0; i < sk_GENERAL_NAME_num(gens); i++) { |
1364 | gena = sk_GENERAL_NAME_value(gens, i); |
1365 | if (gena->type != GEN_DIRNAME) |
1366 | continue; |
1367 | if (!X509_NAME_cmp(nm, gena->d.directoryName)) |
1368 | return 1; |
1369 | } |
1370 | return 0; |
1371 | } |
1372 | |
1373 | /* Else case 3: two GENERAL_NAMES */ |
1374 | |
1375 | for (i = 0; i < sk_GENERAL_NAME_num(a->name.fullname); i++) { |
1376 | gena = sk_GENERAL_NAME_value(a->name.fullname, i); |
1377 | for (j = 0; j < sk_GENERAL_NAME_num(b->name.fullname); j++) { |
1378 | genb = sk_GENERAL_NAME_value(b->name.fullname, j); |
1379 | if (!GENERAL_NAME_cmp(gena, genb)) |
1380 | return 1; |
1381 | } |
1382 | } |
1383 | |
1384 | return 0; |
1385 | |
1386 | } |
1387 | |
1388 | static int crldp_check_crlissuer(DIST_POINT *dp, X509_CRL *crl, int crl_score) |
1389 | { |
1390 | int i; |
1391 | X509_NAME *nm = X509_CRL_get_issuer(crl); |
1392 | /* If no CRLissuer return is successful iff don't need a match */ |
1393 | if (!dp->CRLissuer) |
1394 | return ! !(crl_score & CRL_SCORE_ISSUER_NAME); |
1395 | for (i = 0; i < sk_GENERAL_NAME_num(dp->CRLissuer); i++) { |
1396 | GENERAL_NAME *gen = sk_GENERAL_NAME_value(dp->CRLissuer, i); |
1397 | if (gen->type != GEN_DIRNAME) |
1398 | continue; |
1399 | if (!X509_NAME_cmp(gen->d.directoryName, nm)) |
1400 | return 1; |
1401 | } |
1402 | return 0; |
1403 | } |
1404 | |
1405 | /* Check CRLDP and IDP */ |
1406 | |
1407 | static int crl_crldp_check(X509 *x, X509_CRL *crl, int crl_score, |
1408 | unsigned int *preasons) |
1409 | { |
1410 | int i; |
1411 | if (crl->idp_flags & IDP_ONLYATTR) |
1412 | return 0; |
1413 | if (x->ex_flags & EXFLAG_CA) { |
1414 | if (crl->idp_flags & IDP_ONLYUSER) |
1415 | return 0; |
1416 | } else { |
1417 | if (crl->idp_flags & IDP_ONLYCA) |
1418 | return 0; |
1419 | } |
1420 | *preasons = crl->idp_reasons; |
1421 | for (i = 0; i < sk_DIST_POINT_num(x->crldp); i++) { |
1422 | DIST_POINT *dp = sk_DIST_POINT_value(x->crldp, i); |
1423 | if (crldp_check_crlissuer(dp, crl, crl_score)) { |
1424 | if (!crl->idp || idp_check_dp(dp->distpoint, crl->idp->distpoint)) { |
1425 | *preasons &= dp->dp_reasons; |
1426 | return 1; |
1427 | } |
1428 | } |
1429 | } |
1430 | if ((!crl->idp || !crl->idp->distpoint) |
1431 | && (crl_score & CRL_SCORE_ISSUER_NAME)) |
1432 | return 1; |
1433 | return 0; |
1434 | } |
1435 | |
1436 | /* |
1437 | * Retrieve CRL corresponding to current certificate. If deltas enabled try |
1438 | * to find a delta CRL too |
1439 | */ |
1440 | |
1441 | static int get_crl_delta(X509_STORE_CTX *ctx, |
1442 | X509_CRL **pcrl, X509_CRL **pdcrl, X509 *x) |
1443 | { |
1444 | int ok; |
1445 | X509 *issuer = NULL; |
1446 | int crl_score = 0; |
1447 | unsigned int reasons; |
1448 | X509_CRL *crl = NULL, *dcrl = NULL; |
1449 | STACK_OF(X509_CRL) *skcrl; |
1450 | X509_NAME *nm = X509_get_issuer_name(x); |
1451 | |
1452 | reasons = ctx->current_reasons; |
1453 | ok = get_crl_sk(ctx, &crl, &dcrl, |
1454 | &issuer, &crl_score, &reasons, ctx->crls); |
1455 | if (ok) |
1456 | goto done; |
1457 | |
1458 | /* Lookup CRLs from store */ |
1459 | |
1460 | skcrl = ctx->lookup_crls(ctx, nm); |
1461 | |
1462 | /* If no CRLs found and a near match from get_crl_sk use that */ |
1463 | if (!skcrl && crl) |
1464 | goto done; |
1465 | |
1466 | get_crl_sk(ctx, &crl, &dcrl, &issuer, &crl_score, &reasons, skcrl); |
1467 | |
1468 | sk_X509_CRL_pop_free(skcrl, X509_CRL_free); |
1469 | |
1470 | done: |
1471 | /* If we got any kind of CRL use it and return success */ |
1472 | if (crl) { |
1473 | ctx->current_issuer = issuer; |
1474 | ctx->current_crl_score = crl_score; |
1475 | ctx->current_reasons = reasons; |
1476 | *pcrl = crl; |
1477 | *pdcrl = dcrl; |
1478 | return 1; |
1479 | } |
1480 | return 0; |
1481 | } |
1482 | |
1483 | /* Check CRL validity */ |
1484 | static int check_crl(X509_STORE_CTX *ctx, X509_CRL *crl) |
1485 | { |
1486 | X509 *issuer = NULL; |
1487 | EVP_PKEY *ikey = NULL; |
1488 | int cnum = ctx->error_depth; |
1489 | int chnum = sk_X509_num(ctx->chain) - 1; |
1490 | |
1491 | /* if we have an alternative CRL issuer cert use that */ |
1492 | if (ctx->current_issuer) |
1493 | issuer = ctx->current_issuer; |
1494 | /* |
1495 | * Else find CRL issuer: if not last certificate then issuer is next |
1496 | * certificate in chain. |
1497 | */ |
1498 | else if (cnum < chnum) |
1499 | issuer = sk_X509_value(ctx->chain, cnum + 1); |
1500 | else { |
1501 | issuer = sk_X509_value(ctx->chain, chnum); |
1502 | /* If not self signed, can't check signature */ |
1503 | if (!ctx->check_issued(ctx, issuer, issuer) && |
1504 | !verify_cb_crl(ctx, X509_V_ERR_UNABLE_TO_GET_CRL_ISSUER)) |
1505 | return 0; |
1506 | } |
1507 | |
1508 | if (issuer == NULL) |
1509 | return 1; |
1510 | |
1511 | /* |
1512 | * Skip most tests for deltas because they have already been done |
1513 | */ |
1514 | if (!crl->base_crl_number) { |
1515 | /* Check for cRLSign bit if keyUsage present */ |
1516 | if ((issuer->ex_flags & EXFLAG_KUSAGE) && |
1517 | !(issuer->ex_kusage & KU_CRL_SIGN) && |
1518 | !verify_cb_crl(ctx, X509_V_ERR_KEYUSAGE_NO_CRL_SIGN)) |
1519 | return 0; |
1520 | |
1521 | if (!(ctx->current_crl_score & CRL_SCORE_SCOPE) && |
1522 | !verify_cb_crl(ctx, X509_V_ERR_DIFFERENT_CRL_SCOPE)) |
1523 | return 0; |
1524 | |
1525 | if (!(ctx->current_crl_score & CRL_SCORE_SAME_PATH) && |
1526 | check_crl_path(ctx, ctx->current_issuer) <= 0 && |
1527 | !verify_cb_crl(ctx, X509_V_ERR_CRL_PATH_VALIDATION_ERROR)) |
1528 | return 0; |
1529 | |
1530 | if ((crl->idp_flags & IDP_INVALID) && |
1531 | !verify_cb_crl(ctx, X509_V_ERR_INVALID_EXTENSION)) |
1532 | return 0; |
1533 | } |
1534 | |
1535 | if (!(ctx->current_crl_score & CRL_SCORE_TIME) && |
1536 | !check_crl_time(ctx, crl, 1)) |
1537 | return 0; |
1538 | |
1539 | /* Attempt to get issuer certificate public key */ |
1540 | ikey = X509_get0_pubkey(issuer); |
1541 | |
1542 | if (!ikey && |
1543 | !verify_cb_crl(ctx, X509_V_ERR_UNABLE_TO_DECODE_ISSUER_PUBLIC_KEY)) |
1544 | return 0; |
1545 | |
1546 | if (ikey) { |
1547 | int rv = X509_CRL_check_suiteb(crl, ikey, ctx->param->flags); |
1548 | |
1549 | if (rv != X509_V_OK && !verify_cb_crl(ctx, rv)) |
1550 | return 0; |
1551 | /* Verify CRL signature */ |
1552 | if (X509_CRL_verify(crl, ikey) <= 0 && |
1553 | !verify_cb_crl(ctx, X509_V_ERR_CRL_SIGNATURE_FAILURE)) |
1554 | return 0; |
1555 | } |
1556 | return 1; |
1557 | } |
1558 | |
1559 | /* Check certificate against CRL */ |
1560 | static int cert_crl(X509_STORE_CTX *ctx, X509_CRL *crl, X509 *x) |
1561 | { |
1562 | X509_REVOKED *rev; |
1563 | |
1564 | /* |
1565 | * The rules changed for this... previously if a CRL contained unhandled |
1566 | * critical extensions it could still be used to indicate a certificate |
1567 | * was revoked. This has since been changed since critical extensions can |
1568 | * change the meaning of CRL entries. |
1569 | */ |
1570 | if (!(ctx->param->flags & X509_V_FLAG_IGNORE_CRITICAL) |
1571 | && (crl->flags & EXFLAG_CRITICAL) && |
1572 | !verify_cb_crl(ctx, X509_V_ERR_UNHANDLED_CRITICAL_CRL_EXTENSION)) |
1573 | return 0; |
1574 | /* |
1575 | * Look for serial number of certificate in CRL. If found, make sure |
1576 | * reason is not removeFromCRL. |
1577 | */ |
1578 | if (X509_CRL_get0_by_cert(crl, &rev, x)) { |
1579 | if (rev->reason == CRL_REASON_REMOVE_FROM_CRL) |
1580 | return 2; |
1581 | if (!verify_cb_crl(ctx, X509_V_ERR_CERT_REVOKED)) |
1582 | return 0; |
1583 | } |
1584 | |
1585 | return 1; |
1586 | } |
1587 | |
1588 | static int check_policy(X509_STORE_CTX *ctx) |
1589 | { |
1590 | int ret; |
1591 | |
1592 | if (ctx->parent) |
1593 | return 1; |
1594 | /* |
1595 | * With DANE, the trust anchor might be a bare public key, not a |
1596 | * certificate! In that case our chain does not have the trust anchor |
1597 | * certificate as a top-most element. This comports well with RFC5280 |
1598 | * chain verification, since there too, the trust anchor is not part of the |
1599 | * chain to be verified. In particular, X509_policy_check() does not look |
1600 | * at the TA cert, but assumes that it is present as the top-most chain |
1601 | * element. We therefore temporarily push a NULL cert onto the chain if it |
1602 | * was verified via a bare public key, and pop it off right after the |
1603 | * X509_policy_check() call. |
1604 | */ |
1605 | if (ctx->bare_ta_signed && !sk_X509_push(ctx->chain, NULL)) { |
1606 | X509err(X509_F_CHECK_POLICY, ERR_R_MALLOC_FAILURE); |
1607 | ctx->error = X509_V_ERR_OUT_OF_MEM; |
1608 | return 0; |
1609 | } |
1610 | ret = X509_policy_check(&ctx->tree, &ctx->explicit_policy, ctx->chain, |
1611 | ctx->param->policies, ctx->param->flags); |
1612 | if (ctx->bare_ta_signed) |
1613 | sk_X509_pop(ctx->chain); |
1614 | |
1615 | if (ret == X509_PCY_TREE_INTERNAL) { |
1616 | X509err(X509_F_CHECK_POLICY, ERR_R_MALLOC_FAILURE); |
1617 | ctx->error = X509_V_ERR_OUT_OF_MEM; |
1618 | return 0; |
1619 | } |
1620 | /* Invalid or inconsistent extensions */ |
1621 | if (ret == X509_PCY_TREE_INVALID) { |
1622 | int i; |
1623 | |
1624 | /* Locate certificates with bad extensions and notify callback. */ |
1625 | for (i = 1; i < sk_X509_num(ctx->chain); i++) { |
1626 | X509 *x = sk_X509_value(ctx->chain, i); |
1627 | |
1628 | if (!(x->ex_flags & EXFLAG_INVALID_POLICY)) |
1629 | continue; |
1630 | if (!verify_cb_cert(ctx, x, i, |
1631 | X509_V_ERR_INVALID_POLICY_EXTENSION)) |
1632 | return 0; |
1633 | } |
1634 | return 1; |
1635 | } |
1636 | if (ret == X509_PCY_TREE_FAILURE) { |
1637 | ctx->current_cert = NULL; |
1638 | ctx->error = X509_V_ERR_NO_EXPLICIT_POLICY; |
1639 | return ctx->verify_cb(0, ctx); |
1640 | } |
1641 | if (ret != X509_PCY_TREE_VALID) { |
1642 | X509err(X509_F_CHECK_POLICY, ERR_R_INTERNAL_ERROR); |
1643 | return 0; |
1644 | } |
1645 | |
1646 | if (ctx->param->flags & X509_V_FLAG_NOTIFY_POLICY) { |
1647 | ctx->current_cert = NULL; |
1648 | /* |
1649 | * Verification errors need to be "sticky", a callback may have allowed |
1650 | * an SSL handshake to continue despite an error, and we must then |
1651 | * remain in an error state. Therefore, we MUST NOT clear earlier |
1652 | * verification errors by setting the error to X509_V_OK. |
1653 | */ |
1654 | if (!ctx->verify_cb(2, ctx)) |
1655 | return 0; |
1656 | } |
1657 | |
1658 | return 1; |
1659 | } |
1660 | |
1661 | /*- |
1662 | * Check certificate validity times. |
1663 | * If depth >= 0, invoke verification callbacks on error, otherwise just return |
1664 | * the validation status. |
1665 | * |
1666 | * Return 1 on success, 0 otherwise. |
1667 | */ |
1668 | int x509_check_cert_time(X509_STORE_CTX *ctx, X509 *x, int depth) |
1669 | { |
1670 | time_t *ptime; |
1671 | int i; |
1672 | |
1673 | if (ctx->param->flags & X509_V_FLAG_USE_CHECK_TIME) |
1674 | ptime = &ctx->param->check_time; |
1675 | else if (ctx->param->flags & X509_V_FLAG_NO_CHECK_TIME) |
1676 | return 1; |
1677 | else |
1678 | ptime = NULL; |
1679 | |
1680 | i = X509_cmp_time(X509_get0_notBefore(x), ptime); |
1681 | if (i >= 0 && depth < 0) |
1682 | return 0; |
1683 | if (i == 0 && !verify_cb_cert(ctx, x, depth, |
1684 | X509_V_ERR_ERROR_IN_CERT_NOT_BEFORE_FIELD)) |
1685 | return 0; |
1686 | if (i > 0 && !verify_cb_cert(ctx, x, depth, X509_V_ERR_CERT_NOT_YET_VALID)) |
1687 | return 0; |
1688 | |
1689 | i = X509_cmp_time(X509_get0_notAfter(x), ptime); |
1690 | if (i <= 0 && depth < 0) |
1691 | return 0; |
1692 | if (i == 0 && !verify_cb_cert(ctx, x, depth, |
1693 | X509_V_ERR_ERROR_IN_CERT_NOT_AFTER_FIELD)) |
1694 | return 0; |
1695 | if (i < 0 && !verify_cb_cert(ctx, x, depth, X509_V_ERR_CERT_HAS_EXPIRED)) |
1696 | return 0; |
1697 | return 1; |
1698 | } |
1699 | |
1700 | static int internal_verify(X509_STORE_CTX *ctx) |
1701 | { |
1702 | int n = sk_X509_num(ctx->chain) - 1; |
1703 | X509 *xi = sk_X509_value(ctx->chain, n); |
1704 | X509 *xs; |
1705 | |
1706 | /* |
1707 | * With DANE-verified bare public key TA signatures, it remains only to |
1708 | * check the timestamps of the top certificate. We report the issuer as |
1709 | * NULL, since all we have is a bare key. |
1710 | */ |
1711 | if (ctx->bare_ta_signed) { |
1712 | xs = xi; |
1713 | xi = NULL; |
1714 | goto check_cert; |
1715 | } |
1716 | |
1717 | if (ctx->check_issued(ctx, xi, xi)) |
1718 | xs = xi; |
1719 | else { |
1720 | if (ctx->param->flags & X509_V_FLAG_PARTIAL_CHAIN) { |
1721 | xs = xi; |
1722 | goto check_cert; |
1723 | } |
1724 | if (n <= 0) |
1725 | return verify_cb_cert(ctx, xi, 0, |
1726 | X509_V_ERR_UNABLE_TO_VERIFY_LEAF_SIGNATURE); |
1727 | n--; |
1728 | ctx->error_depth = n; |
1729 | xs = sk_X509_value(ctx->chain, n); |
1730 | } |
1731 | |
1732 | /* |
1733 | * Do not clear ctx->error=0, it must be "sticky", only the user's callback |
1734 | * is allowed to reset errors (at its own peril). |
1735 | */ |
1736 | while (n >= 0) { |
1737 | EVP_PKEY *pkey; |
1738 | |
1739 | /* |
1740 | * Skip signature check for self signed certificates unless explicitly |
1741 | * asked for. It doesn't add any security and just wastes time. If |
1742 | * the issuer's public key is unusable, report the issuer certificate |
1743 | * and its depth (rather than the depth of the subject). |
1744 | */ |
1745 | if (xs != xi || (ctx->param->flags & X509_V_FLAG_CHECK_SS_SIGNATURE)) { |
1746 | if ((pkey = X509_get0_pubkey(xi)) == NULL) { |
1747 | if (!verify_cb_cert(ctx, xi, xi != xs ? n+1 : n, |
1748 | X509_V_ERR_UNABLE_TO_DECODE_ISSUER_PUBLIC_KEY)) |
1749 | return 0; |
1750 | } else if (X509_verify(xs, pkey) <= 0) { |
1751 | if (!verify_cb_cert(ctx, xs, n, |
1752 | X509_V_ERR_CERT_SIGNATURE_FAILURE)) |
1753 | return 0; |
1754 | } |
1755 | } |
1756 | |
1757 | check_cert: |
1758 | /* Calls verify callback as needed */ |
1759 | if (!x509_check_cert_time(ctx, xs, n)) |
1760 | return 0; |
1761 | |
1762 | /* |
1763 | * Signal success at this depth. However, the previous error (if any) |
1764 | * is retained. |
1765 | */ |
1766 | ctx->current_issuer = xi; |
1767 | ctx->current_cert = xs; |
1768 | ctx->error_depth = n; |
1769 | if (!ctx->verify_cb(1, ctx)) |
1770 | return 0; |
1771 | |
1772 | if (--n >= 0) { |
1773 | xi = xs; |
1774 | xs = sk_X509_value(ctx->chain, n); |
1775 | } |
1776 | } |
1777 | return 1; |
1778 | } |
1779 | |
1780 | int X509_cmp_current_time(const ASN1_TIME *ctm) |
1781 | { |
1782 | return X509_cmp_time(ctm, NULL); |
1783 | } |
1784 | |
1785 | int X509_cmp_time(const ASN1_TIME *ctm, time_t *cmp_time) |
1786 | { |
1787 | static const size_t utctime_length = sizeof("YYMMDDHHMMSSZ" ) - 1; |
1788 | static const size_t generalizedtime_length = sizeof("YYYYMMDDHHMMSSZ" ) - 1; |
1789 | ASN1_TIME *asn1_cmp_time = NULL; |
1790 | int i, day, sec, ret = 0; |
1791 | #ifdef CHARSET_EBCDIC |
1792 | const char upper_z = 0x5A; |
1793 | #else |
1794 | const char upper_z = 'Z'; |
1795 | #endif |
1796 | /* |
1797 | * Note that ASN.1 allows much more slack in the time format than RFC5280. |
1798 | * In RFC5280, the representation is fixed: |
1799 | * UTCTime: YYMMDDHHMMSSZ |
1800 | * GeneralizedTime: YYYYMMDDHHMMSSZ |
1801 | * |
1802 | * We do NOT currently enforce the following RFC 5280 requirement: |
1803 | * "CAs conforming to this profile MUST always encode certificate |
1804 | * validity dates through the year 2049 as UTCTime; certificate validity |
1805 | * dates in 2050 or later MUST be encoded as GeneralizedTime." |
1806 | */ |
1807 | switch (ctm->type) { |
1808 | case V_ASN1_UTCTIME: |
1809 | if (ctm->length != (int)(utctime_length)) |
1810 | return 0; |
1811 | break; |
1812 | case V_ASN1_GENERALIZEDTIME: |
1813 | if (ctm->length != (int)(generalizedtime_length)) |
1814 | return 0; |
1815 | break; |
1816 | default: |
1817 | return 0; |
1818 | } |
1819 | |
1820 | /** |
1821 | * Verify the format: the ASN.1 functions we use below allow a more |
1822 | * flexible format than what's mandated by RFC 5280. |
1823 | * Digit and date ranges will be verified in the conversion methods. |
1824 | */ |
1825 | for (i = 0; i < ctm->length - 1; i++) { |
1826 | if (!ascii_isdigit(ctm->data[i])) |
1827 | return 0; |
1828 | } |
1829 | if (ctm->data[ctm->length - 1] != upper_z) |
1830 | return 0; |
1831 | |
1832 | /* |
1833 | * There is ASN1_UTCTIME_cmp_time_t but no |
1834 | * ASN1_GENERALIZEDTIME_cmp_time_t or ASN1_TIME_cmp_time_t, |
1835 | * so we go through ASN.1 |
1836 | */ |
1837 | asn1_cmp_time = X509_time_adj(NULL, 0, cmp_time); |
1838 | if (asn1_cmp_time == NULL) |
1839 | goto err; |
1840 | if (!ASN1_TIME_diff(&day, &sec, ctm, asn1_cmp_time)) |
1841 | goto err; |
1842 | |
1843 | /* |
1844 | * X509_cmp_time comparison is <=. |
1845 | * The return value 0 is reserved for errors. |
1846 | */ |
1847 | ret = (day >= 0 && sec >= 0) ? -1 : 1; |
1848 | |
1849 | err: |
1850 | ASN1_TIME_free(asn1_cmp_time); |
1851 | return ret; |
1852 | } |
1853 | |
1854 | /* |
1855 | * Return 0 if time should not be checked or reference time is in range, |
1856 | * or else 1 if it is past the end, or -1 if it is before the start |
1857 | */ |
1858 | int X509_cmp_timeframe(const X509_VERIFY_PARAM *vpm, |
1859 | const ASN1_TIME *start, const ASN1_TIME *end) |
1860 | { |
1861 | time_t ref_time; |
1862 | time_t *time = NULL; |
1863 | unsigned long flags = vpm == NULL ? 0 : X509_VERIFY_PARAM_get_flags(vpm); |
1864 | |
1865 | if ((flags & X509_V_FLAG_USE_CHECK_TIME) != 0) { |
1866 | ref_time = X509_VERIFY_PARAM_get_time(vpm); |
1867 | time = &ref_time; |
1868 | } else if ((flags & X509_V_FLAG_NO_CHECK_TIME) != 0) { |
1869 | return 0; /* this means ok */ |
1870 | } /* else reference time is the current time */ |
1871 | |
1872 | if (end != NULL && X509_cmp_time(end, time) < 0) |
1873 | return 1; |
1874 | if (start != NULL && X509_cmp_time(start, time) > 0) |
1875 | return -1; |
1876 | return 0; |
1877 | } |
1878 | |
1879 | ASN1_TIME *X509_gmtime_adj(ASN1_TIME *s, long adj) |
1880 | { |
1881 | return X509_time_adj(s, adj, NULL); |
1882 | } |
1883 | |
1884 | ASN1_TIME *X509_time_adj(ASN1_TIME *s, long offset_sec, time_t *in_tm) |
1885 | { |
1886 | return X509_time_adj_ex(s, 0, offset_sec, in_tm); |
1887 | } |
1888 | |
1889 | ASN1_TIME *X509_time_adj_ex(ASN1_TIME *s, |
1890 | int offset_day, long offset_sec, time_t *in_tm) |
1891 | { |
1892 | time_t t; |
1893 | |
1894 | if (in_tm) |
1895 | t = *in_tm; |
1896 | else |
1897 | time(&t); |
1898 | |
1899 | if (s && !(s->flags & ASN1_STRING_FLAG_MSTRING)) { |
1900 | if (s->type == V_ASN1_UTCTIME) |
1901 | return ASN1_UTCTIME_adj(s, t, offset_day, offset_sec); |
1902 | if (s->type == V_ASN1_GENERALIZEDTIME) |
1903 | return ASN1_GENERALIZEDTIME_adj(s, t, offset_day, offset_sec); |
1904 | } |
1905 | return ASN1_TIME_adj(s, t, offset_day, offset_sec); |
1906 | } |
1907 | |
1908 | int X509_get_pubkey_parameters(EVP_PKEY *pkey, STACK_OF(X509) *chain) |
1909 | { |
1910 | EVP_PKEY *ktmp = NULL, *ktmp2; |
1911 | int i, j; |
1912 | |
1913 | if ((pkey != NULL) && !EVP_PKEY_missing_parameters(pkey)) |
1914 | return 1; |
1915 | |
1916 | for (i = 0; i < sk_X509_num(chain); i++) { |
1917 | ktmp = X509_get0_pubkey(sk_X509_value(chain, i)); |
1918 | if (ktmp == NULL) { |
1919 | X509err(X509_F_X509_GET_PUBKEY_PARAMETERS, |
1920 | X509_R_UNABLE_TO_GET_CERTS_PUBLIC_KEY); |
1921 | return 0; |
1922 | } |
1923 | if (!EVP_PKEY_missing_parameters(ktmp)) |
1924 | break; |
1925 | } |
1926 | if (ktmp == NULL) { |
1927 | X509err(X509_F_X509_GET_PUBKEY_PARAMETERS, |
1928 | X509_R_UNABLE_TO_FIND_PARAMETERS_IN_CHAIN); |
1929 | return 0; |
1930 | } |
1931 | |
1932 | /* first, populate the other certs */ |
1933 | for (j = i - 1; j >= 0; j--) { |
1934 | ktmp2 = X509_get0_pubkey(sk_X509_value(chain, j)); |
1935 | EVP_PKEY_copy_parameters(ktmp2, ktmp); |
1936 | } |
1937 | |
1938 | if (pkey != NULL) |
1939 | EVP_PKEY_copy_parameters(pkey, ktmp); |
1940 | return 1; |
1941 | } |
1942 | |
1943 | /* Make a delta CRL as the diff between two full CRLs */ |
1944 | |
1945 | X509_CRL *X509_CRL_diff(X509_CRL *base, X509_CRL *newer, |
1946 | EVP_PKEY *skey, const EVP_MD *md, unsigned int flags) |
1947 | { |
1948 | X509_CRL *crl = NULL; |
1949 | int i; |
1950 | STACK_OF(X509_REVOKED) *revs = NULL; |
1951 | /* CRLs can't be delta already */ |
1952 | if (base->base_crl_number || newer->base_crl_number) { |
1953 | X509err(X509_F_X509_CRL_DIFF, X509_R_CRL_ALREADY_DELTA); |
1954 | return NULL; |
1955 | } |
1956 | /* Base and new CRL must have a CRL number */ |
1957 | if (!base->crl_number || !newer->crl_number) { |
1958 | X509err(X509_F_X509_CRL_DIFF, X509_R_NO_CRL_NUMBER); |
1959 | return NULL; |
1960 | } |
1961 | /* Issuer names must match */ |
1962 | if (X509_NAME_cmp(X509_CRL_get_issuer(base), X509_CRL_get_issuer(newer))) { |
1963 | X509err(X509_F_X509_CRL_DIFF, X509_R_ISSUER_MISMATCH); |
1964 | return NULL; |
1965 | } |
1966 | /* AKID and IDP must match */ |
1967 | if (!crl_extension_match(base, newer, NID_authority_key_identifier)) { |
1968 | X509err(X509_F_X509_CRL_DIFF, X509_R_AKID_MISMATCH); |
1969 | return NULL; |
1970 | } |
1971 | if (!crl_extension_match(base, newer, NID_issuing_distribution_point)) { |
1972 | X509err(X509_F_X509_CRL_DIFF, X509_R_IDP_MISMATCH); |
1973 | return NULL; |
1974 | } |
1975 | /* Newer CRL number must exceed full CRL number */ |
1976 | if (ASN1_INTEGER_cmp(newer->crl_number, base->crl_number) <= 0) { |
1977 | X509err(X509_F_X509_CRL_DIFF, X509_R_NEWER_CRL_NOT_NEWER); |
1978 | return NULL; |
1979 | } |
1980 | /* CRLs must verify */ |
1981 | if (skey && (X509_CRL_verify(base, skey) <= 0 || |
1982 | X509_CRL_verify(newer, skey) <= 0)) { |
1983 | X509err(X509_F_X509_CRL_DIFF, X509_R_CRL_VERIFY_FAILURE); |
1984 | return NULL; |
1985 | } |
1986 | /* Create new CRL */ |
1987 | crl = X509_CRL_new(); |
1988 | if (crl == NULL || !X509_CRL_set_version(crl, 1)) |
1989 | goto memerr; |
1990 | /* Set issuer name */ |
1991 | if (!X509_CRL_set_issuer_name(crl, X509_CRL_get_issuer(newer))) |
1992 | goto memerr; |
1993 | |
1994 | if (!X509_CRL_set1_lastUpdate(crl, X509_CRL_get0_lastUpdate(newer))) |
1995 | goto memerr; |
1996 | if (!X509_CRL_set1_nextUpdate(crl, X509_CRL_get0_nextUpdate(newer))) |
1997 | goto memerr; |
1998 | |
1999 | /* Set base CRL number: must be critical */ |
2000 | |
2001 | if (!X509_CRL_add1_ext_i2d(crl, NID_delta_crl, base->crl_number, 1, 0)) |
2002 | goto memerr; |
2003 | |
2004 | /* |
2005 | * Copy extensions across from newest CRL to delta: this will set CRL |
2006 | * number to correct value too. |
2007 | */ |
2008 | |
2009 | for (i = 0; i < X509_CRL_get_ext_count(newer); i++) { |
2010 | X509_EXTENSION *ext; |
2011 | ext = X509_CRL_get_ext(newer, i); |
2012 | if (!X509_CRL_add_ext(crl, ext, -1)) |
2013 | goto memerr; |
2014 | } |
2015 | |
2016 | /* Go through revoked entries, copying as needed */ |
2017 | |
2018 | revs = X509_CRL_get_REVOKED(newer); |
2019 | |
2020 | for (i = 0; i < sk_X509_REVOKED_num(revs); i++) { |
2021 | X509_REVOKED *rvn, *rvtmp; |
2022 | rvn = sk_X509_REVOKED_value(revs, i); |
2023 | /* |
2024 | * Add only if not also in base. TODO: need something cleverer here |
2025 | * for some more complex CRLs covering multiple CAs. |
2026 | */ |
2027 | if (!X509_CRL_get0_by_serial(base, &rvtmp, &rvn->serialNumber)) { |
2028 | rvtmp = X509_REVOKED_dup(rvn); |
2029 | if (!rvtmp) |
2030 | goto memerr; |
2031 | if (!X509_CRL_add0_revoked(crl, rvtmp)) { |
2032 | X509_REVOKED_free(rvtmp); |
2033 | goto memerr; |
2034 | } |
2035 | } |
2036 | } |
2037 | /* TODO: optionally prune deleted entries */ |
2038 | |
2039 | if (skey && md && !X509_CRL_sign(crl, skey, md)) |
2040 | goto memerr; |
2041 | |
2042 | return crl; |
2043 | |
2044 | memerr: |
2045 | X509err(X509_F_X509_CRL_DIFF, ERR_R_MALLOC_FAILURE); |
2046 | X509_CRL_free(crl); |
2047 | return NULL; |
2048 | } |
2049 | |
2050 | int X509_STORE_CTX_set_ex_data(X509_STORE_CTX *ctx, int idx, void *data) |
2051 | { |
2052 | return CRYPTO_set_ex_data(&ctx->ex_data, idx, data); |
2053 | } |
2054 | |
2055 | void *X509_STORE_CTX_get_ex_data(X509_STORE_CTX *ctx, int idx) |
2056 | { |
2057 | return CRYPTO_get_ex_data(&ctx->ex_data, idx); |
2058 | } |
2059 | |
2060 | int X509_STORE_CTX_get_error(X509_STORE_CTX *ctx) |
2061 | { |
2062 | return ctx->error; |
2063 | } |
2064 | |
2065 | void X509_STORE_CTX_set_error(X509_STORE_CTX *ctx, int err) |
2066 | { |
2067 | ctx->error = err; |
2068 | } |
2069 | |
2070 | int X509_STORE_CTX_get_error_depth(X509_STORE_CTX *ctx) |
2071 | { |
2072 | return ctx->error_depth; |
2073 | } |
2074 | |
2075 | void X509_STORE_CTX_set_error_depth(X509_STORE_CTX *ctx, int depth) |
2076 | { |
2077 | ctx->error_depth = depth; |
2078 | } |
2079 | |
2080 | X509 *X509_STORE_CTX_get_current_cert(X509_STORE_CTX *ctx) |
2081 | { |
2082 | return ctx->current_cert; |
2083 | } |
2084 | |
2085 | void X509_STORE_CTX_set_current_cert(X509_STORE_CTX *ctx, X509 *x) |
2086 | { |
2087 | ctx->current_cert = x; |
2088 | } |
2089 | |
2090 | STACK_OF(X509) *X509_STORE_CTX_get0_chain(X509_STORE_CTX *ctx) |
2091 | { |
2092 | return ctx->chain; |
2093 | } |
2094 | |
2095 | STACK_OF(X509) *X509_STORE_CTX_get1_chain(X509_STORE_CTX *ctx) |
2096 | { |
2097 | if (!ctx->chain) |
2098 | return NULL; |
2099 | return X509_chain_up_ref(ctx->chain); |
2100 | } |
2101 | |
2102 | X509 *X509_STORE_CTX_get0_current_issuer(X509_STORE_CTX *ctx) |
2103 | { |
2104 | return ctx->current_issuer; |
2105 | } |
2106 | |
2107 | X509_CRL *X509_STORE_CTX_get0_current_crl(X509_STORE_CTX *ctx) |
2108 | { |
2109 | return ctx->current_crl; |
2110 | } |
2111 | |
2112 | X509_STORE_CTX *X509_STORE_CTX_get0_parent_ctx(X509_STORE_CTX *ctx) |
2113 | { |
2114 | return ctx->parent; |
2115 | } |
2116 | |
2117 | void X509_STORE_CTX_set_cert(X509_STORE_CTX *ctx, X509 *x) |
2118 | { |
2119 | ctx->cert = x; |
2120 | } |
2121 | |
2122 | void X509_STORE_CTX_set0_crls(X509_STORE_CTX *ctx, STACK_OF(X509_CRL) *sk) |
2123 | { |
2124 | ctx->crls = sk; |
2125 | } |
2126 | |
2127 | int X509_STORE_CTX_set_purpose(X509_STORE_CTX *ctx, int purpose) |
2128 | { |
2129 | /* |
2130 | * XXX: Why isn't this function always used to set the associated trust? |
2131 | * Should there even be a VPM->trust field at all? Or should the trust |
2132 | * always be inferred from the purpose by X509_STORE_CTX_init(). |
2133 | */ |
2134 | return X509_STORE_CTX_purpose_inherit(ctx, 0, purpose, 0); |
2135 | } |
2136 | |
2137 | int X509_STORE_CTX_set_trust(X509_STORE_CTX *ctx, int trust) |
2138 | { |
2139 | /* |
2140 | * XXX: See above, this function would only be needed when the default |
2141 | * trust for the purpose needs an override in a corner case. |
2142 | */ |
2143 | return X509_STORE_CTX_purpose_inherit(ctx, 0, 0, trust); |
2144 | } |
2145 | |
2146 | /* |
2147 | * This function is used to set the X509_STORE_CTX purpose and trust values. |
2148 | * This is intended to be used when another structure has its own trust and |
2149 | * purpose values which (if set) will be inherited by the ctx. If they aren't |
2150 | * set then we will usually have a default purpose in mind which should then |
2151 | * be used to set the trust value. An example of this is SSL use: an SSL |
2152 | * structure will have its own purpose and trust settings which the |
2153 | * application can set: if they aren't set then we use the default of SSL |
2154 | * client/server. |
2155 | */ |
2156 | |
2157 | int X509_STORE_CTX_purpose_inherit(X509_STORE_CTX *ctx, int def_purpose, |
2158 | int purpose, int trust) |
2159 | { |
2160 | int idx; |
2161 | /* If purpose not set use default */ |
2162 | if (purpose == 0) |
2163 | purpose = def_purpose; |
2164 | /* If we have a purpose then check it is valid */ |
2165 | if (purpose != 0) { |
2166 | X509_PURPOSE *ptmp; |
2167 | idx = X509_PURPOSE_get_by_id(purpose); |
2168 | if (idx == -1) { |
2169 | X509err(X509_F_X509_STORE_CTX_PURPOSE_INHERIT, |
2170 | X509_R_UNKNOWN_PURPOSE_ID); |
2171 | return 0; |
2172 | } |
2173 | ptmp = X509_PURPOSE_get0(idx); |
2174 | if (ptmp->trust == X509_TRUST_DEFAULT) { |
2175 | idx = X509_PURPOSE_get_by_id(def_purpose); |
2176 | /* |
2177 | * XXX: In the two callers above def_purpose is always 0, which is |
2178 | * not a known value, so idx will always be -1. How is the |
2179 | * X509_TRUST_DEFAULT case actually supposed to be handled? |
2180 | */ |
2181 | if (idx == -1) { |
2182 | X509err(X509_F_X509_STORE_CTX_PURPOSE_INHERIT, |
2183 | X509_R_UNKNOWN_PURPOSE_ID); |
2184 | return 0; |
2185 | } |
2186 | ptmp = X509_PURPOSE_get0(idx); |
2187 | } |
2188 | /* If trust not set then get from purpose default */ |
2189 | if (!trust) |
2190 | trust = ptmp->trust; |
2191 | } |
2192 | if (trust) { |
2193 | idx = X509_TRUST_get_by_id(trust); |
2194 | if (idx == -1) { |
2195 | X509err(X509_F_X509_STORE_CTX_PURPOSE_INHERIT, |
2196 | X509_R_UNKNOWN_TRUST_ID); |
2197 | return 0; |
2198 | } |
2199 | } |
2200 | |
2201 | if (purpose && !ctx->param->purpose) |
2202 | ctx->param->purpose = purpose; |
2203 | if (trust && !ctx->param->trust) |
2204 | ctx->param->trust = trust; |
2205 | return 1; |
2206 | } |
2207 | |
2208 | X509_STORE_CTX *X509_STORE_CTX_new(void) |
2209 | { |
2210 | X509_STORE_CTX *ctx = OPENSSL_zalloc(sizeof(*ctx)); |
2211 | |
2212 | if (ctx == NULL) { |
2213 | X509err(X509_F_X509_STORE_CTX_NEW, ERR_R_MALLOC_FAILURE); |
2214 | return NULL; |
2215 | } |
2216 | return ctx; |
2217 | } |
2218 | |
2219 | void X509_STORE_CTX_free(X509_STORE_CTX *ctx) |
2220 | { |
2221 | if (ctx == NULL) |
2222 | return; |
2223 | |
2224 | X509_STORE_CTX_cleanup(ctx); |
2225 | OPENSSL_free(ctx); |
2226 | } |
2227 | |
2228 | int X509_STORE_CTX_init(X509_STORE_CTX *ctx, X509_STORE *store, X509 *x509, |
2229 | STACK_OF(X509) *chain) |
2230 | { |
2231 | int ret = 1; |
2232 | |
2233 | ctx->store = store; |
2234 | ctx->cert = x509; |
2235 | ctx->untrusted = chain; |
2236 | ctx->crls = NULL; |
2237 | ctx->num_untrusted = 0; |
2238 | ctx->other_ctx = NULL; |
2239 | ctx->valid = 0; |
2240 | ctx->chain = NULL; |
2241 | ctx->error = 0; |
2242 | ctx->explicit_policy = 0; |
2243 | ctx->error_depth = 0; |
2244 | ctx->current_cert = NULL; |
2245 | ctx->current_issuer = NULL; |
2246 | ctx->current_crl = NULL; |
2247 | ctx->current_crl_score = 0; |
2248 | ctx->current_reasons = 0; |
2249 | ctx->tree = NULL; |
2250 | ctx->parent = NULL; |
2251 | ctx->dane = NULL; |
2252 | ctx->bare_ta_signed = 0; |
2253 | /* Zero ex_data to make sure we're cleanup-safe */ |
2254 | memset(&ctx->ex_data, 0, sizeof(ctx->ex_data)); |
2255 | |
2256 | /* store->cleanup is always 0 in OpenSSL, if set must be idempotent */ |
2257 | if (store) |
2258 | ctx->cleanup = store->cleanup; |
2259 | else |
2260 | ctx->cleanup = 0; |
2261 | |
2262 | if (store && store->check_issued) |
2263 | ctx->check_issued = store->check_issued; |
2264 | else |
2265 | ctx->check_issued = check_issued; |
2266 | |
2267 | if (store && store->get_issuer) |
2268 | ctx->get_issuer = store->get_issuer; |
2269 | else |
2270 | ctx->get_issuer = X509_STORE_CTX_get1_issuer; |
2271 | |
2272 | if (store && store->verify_cb) |
2273 | ctx->verify_cb = store->verify_cb; |
2274 | else |
2275 | ctx->verify_cb = null_callback; |
2276 | |
2277 | if (store && store->verify) |
2278 | ctx->verify = store->verify; |
2279 | else |
2280 | ctx->verify = internal_verify; |
2281 | |
2282 | if (store && store->check_revocation) |
2283 | ctx->check_revocation = store->check_revocation; |
2284 | else |
2285 | ctx->check_revocation = check_revocation; |
2286 | |
2287 | if (store && store->get_crl) |
2288 | ctx->get_crl = store->get_crl; |
2289 | else |
2290 | ctx->get_crl = NULL; |
2291 | |
2292 | if (store && store->check_crl) |
2293 | ctx->check_crl = store->check_crl; |
2294 | else |
2295 | ctx->check_crl = check_crl; |
2296 | |
2297 | if (store && store->cert_crl) |
2298 | ctx->cert_crl = store->cert_crl; |
2299 | else |
2300 | ctx->cert_crl = cert_crl; |
2301 | |
2302 | if (store && store->check_policy) |
2303 | ctx->check_policy = store->check_policy; |
2304 | else |
2305 | ctx->check_policy = check_policy; |
2306 | |
2307 | if (store && store->lookup_certs) |
2308 | ctx->lookup_certs = store->lookup_certs; |
2309 | else |
2310 | ctx->lookup_certs = X509_STORE_CTX_get1_certs; |
2311 | |
2312 | if (store && store->lookup_crls) |
2313 | ctx->lookup_crls = store->lookup_crls; |
2314 | else |
2315 | ctx->lookup_crls = X509_STORE_CTX_get1_crls; |
2316 | |
2317 | ctx->param = X509_VERIFY_PARAM_new(); |
2318 | if (ctx->param == NULL) { |
2319 | X509err(X509_F_X509_STORE_CTX_INIT, ERR_R_MALLOC_FAILURE); |
2320 | goto err; |
2321 | } |
2322 | |
2323 | /* |
2324 | * Inherit callbacks and flags from X509_STORE if not set use defaults. |
2325 | */ |
2326 | if (store) |
2327 | ret = X509_VERIFY_PARAM_inherit(ctx->param, store->param); |
2328 | else |
2329 | ctx->param->inh_flags |= X509_VP_FLAG_DEFAULT | X509_VP_FLAG_ONCE; |
2330 | |
2331 | if (ret) |
2332 | ret = X509_VERIFY_PARAM_inherit(ctx->param, |
2333 | X509_VERIFY_PARAM_lookup("default" )); |
2334 | |
2335 | if (ret == 0) { |
2336 | X509err(X509_F_X509_STORE_CTX_INIT, ERR_R_MALLOC_FAILURE); |
2337 | goto err; |
2338 | } |
2339 | |
2340 | /* |
2341 | * XXX: For now, continue to inherit trust from VPM, but infer from the |
2342 | * purpose if this still yields the default value. |
2343 | */ |
2344 | if (ctx->param->trust == X509_TRUST_DEFAULT) { |
2345 | int idx = X509_PURPOSE_get_by_id(ctx->param->purpose); |
2346 | X509_PURPOSE *xp = X509_PURPOSE_get0(idx); |
2347 | |
2348 | if (xp != NULL) |
2349 | ctx->param->trust = X509_PURPOSE_get_trust(xp); |
2350 | } |
2351 | |
2352 | if (CRYPTO_new_ex_data(CRYPTO_EX_INDEX_X509_STORE_CTX, ctx, |
2353 | &ctx->ex_data)) |
2354 | return 1; |
2355 | X509err(X509_F_X509_STORE_CTX_INIT, ERR_R_MALLOC_FAILURE); |
2356 | |
2357 | err: |
2358 | /* |
2359 | * On error clean up allocated storage, if the store context was not |
2360 | * allocated with X509_STORE_CTX_new() this is our last chance to do so. |
2361 | */ |
2362 | X509_STORE_CTX_cleanup(ctx); |
2363 | return 0; |
2364 | } |
2365 | |
2366 | /* |
2367 | * Set alternative lookup method: just a STACK of trusted certificates. This |
2368 | * avoids X509_STORE nastiness where it isn't needed. |
2369 | */ |
2370 | void X509_STORE_CTX_set0_trusted_stack(X509_STORE_CTX *ctx, STACK_OF(X509) *sk) |
2371 | { |
2372 | ctx->other_ctx = sk; |
2373 | ctx->get_issuer = get_issuer_sk; |
2374 | ctx->lookup_certs = lookup_certs_sk; |
2375 | } |
2376 | |
2377 | void X509_STORE_CTX_cleanup(X509_STORE_CTX *ctx) |
2378 | { |
2379 | /* |
2380 | * We need to be idempotent because, unfortunately, free() also calls |
2381 | * cleanup(), so the natural call sequence new(), init(), cleanup(), free() |
2382 | * calls cleanup() for the same object twice! Thus we must zero the |
2383 | * pointers below after they're freed! |
2384 | */ |
2385 | /* Seems to always be 0 in OpenSSL, do this at most once. */ |
2386 | if (ctx->cleanup != NULL) { |
2387 | ctx->cleanup(ctx); |
2388 | ctx->cleanup = NULL; |
2389 | } |
2390 | if (ctx->param != NULL) { |
2391 | if (ctx->parent == NULL) |
2392 | X509_VERIFY_PARAM_free(ctx->param); |
2393 | ctx->param = NULL; |
2394 | } |
2395 | X509_policy_tree_free(ctx->tree); |
2396 | ctx->tree = NULL; |
2397 | sk_X509_pop_free(ctx->chain, X509_free); |
2398 | ctx->chain = NULL; |
2399 | CRYPTO_free_ex_data(CRYPTO_EX_INDEX_X509_STORE_CTX, ctx, &(ctx->ex_data)); |
2400 | memset(&ctx->ex_data, 0, sizeof(ctx->ex_data)); |
2401 | } |
2402 | |
2403 | void X509_STORE_CTX_set_depth(X509_STORE_CTX *ctx, int depth) |
2404 | { |
2405 | X509_VERIFY_PARAM_set_depth(ctx->param, depth); |
2406 | } |
2407 | |
2408 | void X509_STORE_CTX_set_flags(X509_STORE_CTX *ctx, unsigned long flags) |
2409 | { |
2410 | X509_VERIFY_PARAM_set_flags(ctx->param, flags); |
2411 | } |
2412 | |
2413 | void X509_STORE_CTX_set_time(X509_STORE_CTX *ctx, unsigned long flags, |
2414 | time_t t) |
2415 | { |
2416 | X509_VERIFY_PARAM_set_time(ctx->param, t); |
2417 | } |
2418 | |
2419 | X509 *X509_STORE_CTX_get0_cert(X509_STORE_CTX *ctx) |
2420 | { |
2421 | return ctx->cert; |
2422 | } |
2423 | |
2424 | STACK_OF(X509) *X509_STORE_CTX_get0_untrusted(X509_STORE_CTX *ctx) |
2425 | { |
2426 | return ctx->untrusted; |
2427 | } |
2428 | |
2429 | void X509_STORE_CTX_set0_untrusted(X509_STORE_CTX *ctx, STACK_OF(X509) *sk) |
2430 | { |
2431 | ctx->untrusted = sk; |
2432 | } |
2433 | |
2434 | void X509_STORE_CTX_set0_verified_chain(X509_STORE_CTX *ctx, STACK_OF(X509) *sk) |
2435 | { |
2436 | sk_X509_pop_free(ctx->chain, X509_free); |
2437 | ctx->chain = sk; |
2438 | } |
2439 | |
2440 | void X509_STORE_CTX_set_verify_cb(X509_STORE_CTX *ctx, |
2441 | X509_STORE_CTX_verify_cb verify_cb) |
2442 | { |
2443 | ctx->verify_cb = verify_cb; |
2444 | } |
2445 | |
2446 | X509_STORE_CTX_verify_cb X509_STORE_CTX_get_verify_cb(X509_STORE_CTX *ctx) |
2447 | { |
2448 | return ctx->verify_cb; |
2449 | } |
2450 | |
2451 | void X509_STORE_CTX_set_verify(X509_STORE_CTX *ctx, |
2452 | X509_STORE_CTX_verify_fn verify) |
2453 | { |
2454 | ctx->verify = verify; |
2455 | } |
2456 | |
2457 | X509_STORE_CTX_verify_fn X509_STORE_CTX_get_verify(X509_STORE_CTX *ctx) |
2458 | { |
2459 | return ctx->verify; |
2460 | } |
2461 | |
2462 | X509_STORE_CTX_get_issuer_fn X509_STORE_CTX_get_get_issuer(X509_STORE_CTX *ctx) |
2463 | { |
2464 | return ctx->get_issuer; |
2465 | } |
2466 | |
2467 | X509_STORE_CTX_check_issued_fn X509_STORE_CTX_get_check_issued(X509_STORE_CTX *ctx) |
2468 | { |
2469 | return ctx->check_issued; |
2470 | } |
2471 | |
2472 | X509_STORE_CTX_check_revocation_fn X509_STORE_CTX_get_check_revocation(X509_STORE_CTX *ctx) |
2473 | { |
2474 | return ctx->check_revocation; |
2475 | } |
2476 | |
2477 | X509_STORE_CTX_get_crl_fn X509_STORE_CTX_get_get_crl(X509_STORE_CTX *ctx) |
2478 | { |
2479 | return ctx->get_crl; |
2480 | } |
2481 | |
2482 | X509_STORE_CTX_check_crl_fn X509_STORE_CTX_get_check_crl(X509_STORE_CTX *ctx) |
2483 | { |
2484 | return ctx->check_crl; |
2485 | } |
2486 | |
2487 | X509_STORE_CTX_cert_crl_fn X509_STORE_CTX_get_cert_crl(X509_STORE_CTX *ctx) |
2488 | { |
2489 | return ctx->cert_crl; |
2490 | } |
2491 | |
2492 | X509_STORE_CTX_check_policy_fn X509_STORE_CTX_get_check_policy(X509_STORE_CTX *ctx) |
2493 | { |
2494 | return ctx->check_policy; |
2495 | } |
2496 | |
2497 | X509_STORE_CTX_lookup_certs_fn X509_STORE_CTX_get_lookup_certs(X509_STORE_CTX *ctx) |
2498 | { |
2499 | return ctx->lookup_certs; |
2500 | } |
2501 | |
2502 | X509_STORE_CTX_lookup_crls_fn X509_STORE_CTX_get_lookup_crls(X509_STORE_CTX *ctx) |
2503 | { |
2504 | return ctx->lookup_crls; |
2505 | } |
2506 | |
2507 | X509_STORE_CTX_cleanup_fn X509_STORE_CTX_get_cleanup(X509_STORE_CTX *ctx) |
2508 | { |
2509 | return ctx->cleanup; |
2510 | } |
2511 | |
2512 | X509_POLICY_TREE *X509_STORE_CTX_get0_policy_tree(X509_STORE_CTX *ctx) |
2513 | { |
2514 | return ctx->tree; |
2515 | } |
2516 | |
2517 | int X509_STORE_CTX_get_explicit_policy(X509_STORE_CTX *ctx) |
2518 | { |
2519 | return ctx->explicit_policy; |
2520 | } |
2521 | |
2522 | int X509_STORE_CTX_get_num_untrusted(X509_STORE_CTX *ctx) |
2523 | { |
2524 | return ctx->num_untrusted; |
2525 | } |
2526 | |
2527 | int X509_STORE_CTX_set_default(X509_STORE_CTX *ctx, const char *name) |
2528 | { |
2529 | const X509_VERIFY_PARAM *param; |
2530 | |
2531 | param = X509_VERIFY_PARAM_lookup(name); |
2532 | if (param == NULL) |
2533 | return 0; |
2534 | return X509_VERIFY_PARAM_inherit(ctx->param, param); |
2535 | } |
2536 | |
2537 | X509_VERIFY_PARAM *X509_STORE_CTX_get0_param(X509_STORE_CTX *ctx) |
2538 | { |
2539 | return ctx->param; |
2540 | } |
2541 | |
2542 | void X509_STORE_CTX_set0_param(X509_STORE_CTX *ctx, X509_VERIFY_PARAM *param) |
2543 | { |
2544 | X509_VERIFY_PARAM_free(ctx->param); |
2545 | ctx->param = param; |
2546 | } |
2547 | |
2548 | void X509_STORE_CTX_set0_dane(X509_STORE_CTX *ctx, SSL_DANE *dane) |
2549 | { |
2550 | ctx->dane = dane; |
2551 | } |
2552 | |
2553 | static unsigned char *dane_i2d( |
2554 | X509 *cert, |
2555 | uint8_t selector, |
2556 | unsigned int *i2dlen) |
2557 | { |
2558 | unsigned char *buf = NULL; |
2559 | int len; |
2560 | |
2561 | /* |
2562 | * Extract ASN.1 DER form of certificate or public key. |
2563 | */ |
2564 | switch (selector) { |
2565 | case DANETLS_SELECTOR_CERT: |
2566 | len = i2d_X509(cert, &buf); |
2567 | break; |
2568 | case DANETLS_SELECTOR_SPKI: |
2569 | len = i2d_X509_PUBKEY(X509_get_X509_PUBKEY(cert), &buf); |
2570 | break; |
2571 | default: |
2572 | X509err(X509_F_DANE_I2D, X509_R_BAD_SELECTOR); |
2573 | return NULL; |
2574 | } |
2575 | |
2576 | if (len < 0 || buf == NULL) { |
2577 | X509err(X509_F_DANE_I2D, ERR_R_MALLOC_FAILURE); |
2578 | return NULL; |
2579 | } |
2580 | |
2581 | *i2dlen = (unsigned int)len; |
2582 | return buf; |
2583 | } |
2584 | |
2585 | #define DANETLS_NONE 256 /* impossible uint8_t */ |
2586 | |
2587 | static int dane_match(X509_STORE_CTX *ctx, X509 *cert, int depth) |
2588 | { |
2589 | SSL_DANE *dane = ctx->dane; |
2590 | unsigned usage = DANETLS_NONE; |
2591 | unsigned selector = DANETLS_NONE; |
2592 | unsigned ordinal = DANETLS_NONE; |
2593 | unsigned mtype = DANETLS_NONE; |
2594 | unsigned char *i2dbuf = NULL; |
2595 | unsigned int i2dlen = 0; |
2596 | unsigned char mdbuf[EVP_MAX_MD_SIZE]; |
2597 | unsigned char *cmpbuf = NULL; |
2598 | unsigned int cmplen = 0; |
2599 | int i; |
2600 | int recnum; |
2601 | int matched = 0; |
2602 | danetls_record *t = NULL; |
2603 | uint32_t mask; |
2604 | |
2605 | mask = (depth == 0) ? DANETLS_EE_MASK : DANETLS_TA_MASK; |
2606 | |
2607 | /* |
2608 | * The trust store is not applicable with DANE-TA(2) |
2609 | */ |
2610 | if (depth >= ctx->num_untrusted) |
2611 | mask &= DANETLS_PKIX_MASK; |
2612 | |
2613 | /* |
2614 | * If we've previously matched a PKIX-?? record, no need to test any |
2615 | * further PKIX-?? records, it remains to just build the PKIX chain. |
2616 | * Had the match been a DANE-?? record, we'd be done already. |
2617 | */ |
2618 | if (dane->mdpth >= 0) |
2619 | mask &= ~DANETLS_PKIX_MASK; |
2620 | |
2621 | /*- |
2622 | * https://tools.ietf.org/html/rfc7671#section-5.1 |
2623 | * https://tools.ietf.org/html/rfc7671#section-5.2 |
2624 | * https://tools.ietf.org/html/rfc7671#section-5.3 |
2625 | * https://tools.ietf.org/html/rfc7671#section-5.4 |
2626 | * |
2627 | * We handle DANE-EE(3) records first as they require no chain building |
2628 | * and no expiration or hostname checks. We also process digests with |
2629 | * higher ordinals first and ignore lower priorities except Full(0) which |
2630 | * is always processed (last). If none match, we then process PKIX-EE(1). |
2631 | * |
2632 | * NOTE: This relies on DANE usages sorting before the corresponding PKIX |
2633 | * usages in SSL_dane_tlsa_add(), and also on descending sorting of digest |
2634 | * priorities. See twin comment in ssl/ssl_lib.c. |
2635 | * |
2636 | * We expect that most TLSA RRsets will have just a single usage, so we |
2637 | * don't go out of our way to cache multiple selector-specific i2d buffers |
2638 | * across usages, but if the selector happens to remain the same as switch |
2639 | * usages, that's OK. Thus, a set of "3 1 1", "3 0 1", "1 1 1", "1 0 1", |
2640 | * records would result in us generating each of the certificate and public |
2641 | * key DER forms twice, but more typically we'd just see multiple "3 1 1" |
2642 | * or multiple "3 0 1" records. |
2643 | * |
2644 | * As soon as we find a match at any given depth, we stop, because either |
2645 | * we've matched a DANE-?? record and the peer is authenticated, or, after |
2646 | * exhausting all DANE-?? records, we've matched a PKIX-?? record, which is |
2647 | * sufficient for DANE, and what remains to do is ordinary PKIX validation. |
2648 | */ |
2649 | recnum = (dane->umask & mask) ? sk_danetls_record_num(dane->trecs) : 0; |
2650 | for (i = 0; matched == 0 && i < recnum; ++i) { |
2651 | t = sk_danetls_record_value(dane->trecs, i); |
2652 | if ((DANETLS_USAGE_BIT(t->usage) & mask) == 0) |
2653 | continue; |
2654 | if (t->usage != usage) { |
2655 | usage = t->usage; |
2656 | |
2657 | /* Reset digest agility for each usage/selector pair */ |
2658 | mtype = DANETLS_NONE; |
2659 | ordinal = dane->dctx->mdord[t->mtype]; |
2660 | } |
2661 | if (t->selector != selector) { |
2662 | selector = t->selector; |
2663 | |
2664 | /* Update per-selector state */ |
2665 | OPENSSL_free(i2dbuf); |
2666 | i2dbuf = dane_i2d(cert, selector, &i2dlen); |
2667 | if (i2dbuf == NULL) |
2668 | return -1; |
2669 | |
2670 | /* Reset digest agility for each usage/selector pair */ |
2671 | mtype = DANETLS_NONE; |
2672 | ordinal = dane->dctx->mdord[t->mtype]; |
2673 | } else if (t->mtype != DANETLS_MATCHING_FULL) { |
2674 | /*- |
2675 | * Digest agility: |
2676 | * |
2677 | * <https://tools.ietf.org/html/rfc7671#section-9> |
2678 | * |
2679 | * For a fixed selector, after processing all records with the |
2680 | * highest mtype ordinal, ignore all mtypes with lower ordinals |
2681 | * other than "Full". |
2682 | */ |
2683 | if (dane->dctx->mdord[t->mtype] < ordinal) |
2684 | continue; |
2685 | } |
2686 | |
2687 | /* |
2688 | * Each time we hit a (new selector or) mtype, re-compute the relevant |
2689 | * digest, more complex caching is not worth the code space. |
2690 | */ |
2691 | if (t->mtype != mtype) { |
2692 | const EVP_MD *md = dane->dctx->mdevp[mtype = t->mtype]; |
2693 | cmpbuf = i2dbuf; |
2694 | cmplen = i2dlen; |
2695 | |
2696 | if (md != NULL) { |
2697 | cmpbuf = mdbuf; |
2698 | if (!EVP_Digest(i2dbuf, i2dlen, cmpbuf, &cmplen, md, 0)) { |
2699 | matched = -1; |
2700 | break; |
2701 | } |
2702 | } |
2703 | } |
2704 | |
2705 | /* |
2706 | * Squirrel away the certificate and depth if we have a match. Any |
2707 | * DANE match is dispositive, but with PKIX we still need to build a |
2708 | * full chain. |
2709 | */ |
2710 | if (cmplen == t->dlen && |
2711 | memcmp(cmpbuf, t->data, cmplen) == 0) { |
2712 | if (DANETLS_USAGE_BIT(usage) & DANETLS_DANE_MASK) |
2713 | matched = 1; |
2714 | if (matched || dane->mdpth < 0) { |
2715 | dane->mdpth = depth; |
2716 | dane->mtlsa = t; |
2717 | OPENSSL_free(dane->mcert); |
2718 | dane->mcert = cert; |
2719 | X509_up_ref(cert); |
2720 | } |
2721 | break; |
2722 | } |
2723 | } |
2724 | |
2725 | /* Clear the one-element DER cache */ |
2726 | OPENSSL_free(i2dbuf); |
2727 | return matched; |
2728 | } |
2729 | |
2730 | static int check_dane_issuer(X509_STORE_CTX *ctx, int depth) |
2731 | { |
2732 | SSL_DANE *dane = ctx->dane; |
2733 | int matched = 0; |
2734 | X509 *cert; |
2735 | |
2736 | if (!DANETLS_HAS_TA(dane) || depth == 0) |
2737 | return X509_TRUST_UNTRUSTED; |
2738 | |
2739 | /* |
2740 | * Record any DANE trust-anchor matches, for the first depth to test, if |
2741 | * there's one at that depth. (This'll be false for length 1 chains looking |
2742 | * for an exact match for the leaf certificate). |
2743 | */ |
2744 | cert = sk_X509_value(ctx->chain, depth); |
2745 | if (cert != NULL && (matched = dane_match(ctx, cert, depth)) < 0) |
2746 | return X509_TRUST_REJECTED; |
2747 | if (matched > 0) { |
2748 | ctx->num_untrusted = depth - 1; |
2749 | return X509_TRUST_TRUSTED; |
2750 | } |
2751 | |
2752 | return X509_TRUST_UNTRUSTED; |
2753 | } |
2754 | |
2755 | static int check_dane_pkeys(X509_STORE_CTX *ctx) |
2756 | { |
2757 | SSL_DANE *dane = ctx->dane; |
2758 | danetls_record *t; |
2759 | int num = ctx->num_untrusted; |
2760 | X509 *cert = sk_X509_value(ctx->chain, num - 1); |
2761 | int recnum = sk_danetls_record_num(dane->trecs); |
2762 | int i; |
2763 | |
2764 | for (i = 0; i < recnum; ++i) { |
2765 | t = sk_danetls_record_value(dane->trecs, i); |
2766 | if (t->usage != DANETLS_USAGE_DANE_TA || |
2767 | t->selector != DANETLS_SELECTOR_SPKI || |
2768 | t->mtype != DANETLS_MATCHING_FULL || |
2769 | X509_verify(cert, t->spki) <= 0) |
2770 | continue; |
2771 | |
2772 | /* Clear any PKIX-?? matches that failed to extend to a full chain */ |
2773 | X509_free(dane->mcert); |
2774 | dane->mcert = NULL; |
2775 | |
2776 | /* Record match via a bare TA public key */ |
2777 | ctx->bare_ta_signed = 1; |
2778 | dane->mdpth = num - 1; |
2779 | dane->mtlsa = t; |
2780 | |
2781 | /* Prune any excess chain certificates */ |
2782 | num = sk_X509_num(ctx->chain); |
2783 | for (; num > ctx->num_untrusted; --num) |
2784 | X509_free(sk_X509_pop(ctx->chain)); |
2785 | |
2786 | return X509_TRUST_TRUSTED; |
2787 | } |
2788 | |
2789 | return X509_TRUST_UNTRUSTED; |
2790 | } |
2791 | |
2792 | static void dane_reset(SSL_DANE *dane) |
2793 | { |
2794 | /* |
2795 | * Reset state to verify another chain, or clear after failure. |
2796 | */ |
2797 | X509_free(dane->mcert); |
2798 | dane->mcert = NULL; |
2799 | dane->mtlsa = NULL; |
2800 | dane->mdpth = -1; |
2801 | dane->pdpth = -1; |
2802 | } |
2803 | |
2804 | static int check_leaf_suiteb(X509_STORE_CTX *ctx, X509 *cert) |
2805 | { |
2806 | int err = X509_chain_check_suiteb(NULL, cert, NULL, ctx->param->flags); |
2807 | |
2808 | if (err == X509_V_OK) |
2809 | return 1; |
2810 | return verify_cb_cert(ctx, cert, 0, err); |
2811 | } |
2812 | |
2813 | static int dane_verify(X509_STORE_CTX *ctx) |
2814 | { |
2815 | X509 *cert = ctx->cert; |
2816 | SSL_DANE *dane = ctx->dane; |
2817 | int matched; |
2818 | int done; |
2819 | |
2820 | dane_reset(dane); |
2821 | |
2822 | /*- |
2823 | * When testing the leaf certificate, if we match a DANE-EE(3) record, |
2824 | * dane_match() returns 1 and we're done. If however we match a PKIX-EE(1) |
2825 | * record, the match depth and matching TLSA record are recorded, but the |
2826 | * return value is 0, because we still need to find a PKIX trust-anchor. |
2827 | * Therefore, when DANE authentication is enabled (required), we're done |
2828 | * if: |
2829 | * + matched < 0, internal error. |
2830 | * + matched == 1, we matched a DANE-EE(3) record |
2831 | * + matched == 0, mdepth < 0 (no PKIX-EE match) and there are no |
2832 | * DANE-TA(2) or PKIX-TA(0) to test. |
2833 | */ |
2834 | matched = dane_match(ctx, ctx->cert, 0); |
2835 | done = matched != 0 || (!DANETLS_HAS_TA(dane) && dane->mdpth < 0); |
2836 | |
2837 | if (done) |
2838 | X509_get_pubkey_parameters(NULL, ctx->chain); |
2839 | |
2840 | if (matched > 0) { |
2841 | /* Callback invoked as needed */ |
2842 | if (!check_leaf_suiteb(ctx, cert)) |
2843 | return 0; |
2844 | /* Callback invoked as needed */ |
2845 | if ((dane->flags & DANE_FLAG_NO_DANE_EE_NAMECHECKS) == 0 && |
2846 | !check_id(ctx)) |
2847 | return 0; |
2848 | /* Bypass internal_verify(), issue depth 0 success callback */ |
2849 | ctx->error_depth = 0; |
2850 | ctx->current_cert = cert; |
2851 | return ctx->verify_cb(1, ctx); |
2852 | } |
2853 | |
2854 | if (matched < 0) { |
2855 | ctx->error_depth = 0; |
2856 | ctx->current_cert = cert; |
2857 | ctx->error = X509_V_ERR_OUT_OF_MEM; |
2858 | return -1; |
2859 | } |
2860 | |
2861 | if (done) { |
2862 | /* Fail early, TA-based success is not possible */ |
2863 | if (!check_leaf_suiteb(ctx, cert)) |
2864 | return 0; |
2865 | return verify_cb_cert(ctx, cert, 0, X509_V_ERR_DANE_NO_MATCH); |
2866 | } |
2867 | |
2868 | /* |
2869 | * Chain verification for usages 0/1/2. TLSA record matching of depth > 0 |
2870 | * certificates happens in-line with building the rest of the chain. |
2871 | */ |
2872 | return verify_chain(ctx); |
2873 | } |
2874 | |
2875 | /* Get issuer, without duplicate suppression */ |
2876 | static int get_issuer(X509 **issuer, X509_STORE_CTX *ctx, X509 *cert) |
2877 | { |
2878 | STACK_OF(X509) *saved_chain = ctx->chain; |
2879 | int ok; |
2880 | |
2881 | ctx->chain = NULL; |
2882 | ok = ctx->get_issuer(issuer, ctx, cert); |
2883 | ctx->chain = saved_chain; |
2884 | |
2885 | return ok; |
2886 | } |
2887 | |
2888 | static int build_chain(X509_STORE_CTX *ctx) |
2889 | { |
2890 | SSL_DANE *dane = ctx->dane; |
2891 | int num = sk_X509_num(ctx->chain); |
2892 | X509 *cert = sk_X509_value(ctx->chain, num - 1); |
2893 | int ss = cert_self_signed(cert); |
2894 | STACK_OF(X509) *sktmp = NULL; |
2895 | unsigned int search; |
2896 | int may_trusted = 0; |
2897 | int may_alternate = 0; |
2898 | int trust = X509_TRUST_UNTRUSTED; |
2899 | int alt_untrusted = 0; |
2900 | int depth; |
2901 | int ok = 0; |
2902 | int i; |
2903 | |
2904 | /* Our chain starts with a single untrusted element. */ |
2905 | if (!ossl_assert(num == 1 && ctx->num_untrusted == num)) { |
2906 | X509err(X509_F_BUILD_CHAIN, ERR_R_INTERNAL_ERROR); |
2907 | ctx->error = X509_V_ERR_UNSPECIFIED; |
2908 | return 0; |
2909 | } |
2910 | |
2911 | #define S_DOUNTRUSTED (1 << 0) /* Search untrusted chain */ |
2912 | #define S_DOTRUSTED (1 << 1) /* Search trusted store */ |
2913 | #define S_DOALTERNATE (1 << 2) /* Retry with pruned alternate chain */ |
2914 | /* |
2915 | * Set up search policy, untrusted if possible, trusted-first if enabled. |
2916 | * If we're doing DANE and not doing PKIX-TA/PKIX-EE, we never look in the |
2917 | * trust_store, otherwise we might look there first. If not trusted-first, |
2918 | * and alternate chains are not disabled, try building an alternate chain |
2919 | * if no luck with untrusted first. |
2920 | */ |
2921 | search = (ctx->untrusted != NULL) ? S_DOUNTRUSTED : 0; |
2922 | if (DANETLS_HAS_PKIX(dane) || !DANETLS_HAS_DANE(dane)) { |
2923 | if (search == 0 || ctx->param->flags & X509_V_FLAG_TRUSTED_FIRST) |
2924 | search |= S_DOTRUSTED; |
2925 | else if (!(ctx->param->flags & X509_V_FLAG_NO_ALT_CHAINS)) |
2926 | may_alternate = 1; |
2927 | may_trusted = 1; |
2928 | } |
2929 | |
2930 | /* |
2931 | * Shallow-copy the stack of untrusted certificates (with TLS, this is |
2932 | * typically the content of the peer's certificate message) so can make |
2933 | * multiple passes over it, while free to remove elements as we go. |
2934 | */ |
2935 | if (ctx->untrusted && (sktmp = sk_X509_dup(ctx->untrusted)) == NULL) { |
2936 | X509err(X509_F_BUILD_CHAIN, ERR_R_MALLOC_FAILURE); |
2937 | ctx->error = X509_V_ERR_OUT_OF_MEM; |
2938 | return 0; |
2939 | } |
2940 | |
2941 | /* |
2942 | * If we got any "DANE-TA(2) Cert(0) Full(0)" trust-anchors from DNS, add |
2943 | * them to our working copy of the untrusted certificate stack. Since the |
2944 | * caller of X509_STORE_CTX_init() may have provided only a leaf cert with |
2945 | * no corresponding stack of untrusted certificates, we may need to create |
2946 | * an empty stack first. [ At present only the ssl library provides DANE |
2947 | * support, and ssl_verify_cert_chain() always provides a non-null stack |
2948 | * containing at least the leaf certificate, but we must be prepared for |
2949 | * this to change. ] |
2950 | */ |
2951 | if (DANETLS_ENABLED(dane) && dane->certs != NULL) { |
2952 | if (sktmp == NULL && (sktmp = sk_X509_new_null()) == NULL) { |
2953 | X509err(X509_F_BUILD_CHAIN, ERR_R_MALLOC_FAILURE); |
2954 | ctx->error = X509_V_ERR_OUT_OF_MEM; |
2955 | return 0; |
2956 | } |
2957 | for (i = 0; i < sk_X509_num(dane->certs); ++i) { |
2958 | if (!sk_X509_push(sktmp, sk_X509_value(dane->certs, i))) { |
2959 | sk_X509_free(sktmp); |
2960 | X509err(X509_F_BUILD_CHAIN, ERR_R_MALLOC_FAILURE); |
2961 | ctx->error = X509_V_ERR_OUT_OF_MEM; |
2962 | return 0; |
2963 | } |
2964 | } |
2965 | } |
2966 | |
2967 | /* |
2968 | * Still absurdly large, but arithmetically safe, a lower hard upper bound |
2969 | * might be reasonable. |
2970 | */ |
2971 | if (ctx->param->depth > INT_MAX/2) |
2972 | ctx->param->depth = INT_MAX/2; |
2973 | |
2974 | /* |
2975 | * Try to Extend the chain until we reach an ultimately trusted issuer. |
2976 | * Build chains up to one longer the limit, later fail if we hit the limit, |
2977 | * with an X509_V_ERR_CERT_CHAIN_TOO_LONG error code. |
2978 | */ |
2979 | depth = ctx->param->depth + 1; |
2980 | |
2981 | while (search != 0) { |
2982 | X509 *x; |
2983 | X509 *xtmp = NULL; |
2984 | |
2985 | /* |
2986 | * Look in the trust store if enabled for first lookup, or we've run |
2987 | * out of untrusted issuers and search here is not disabled. When we |
2988 | * reach the depth limit, we stop extending the chain, if by that point |
2989 | * we've not found a trust-anchor, any trusted chain would be too long. |
2990 | * |
2991 | * The error reported to the application verify callback is at the |
2992 | * maximal valid depth with the current certificate equal to the last |
2993 | * not ultimately-trusted issuer. For example, with verify_depth = 0, |
2994 | * the callback will report errors at depth=1 when the immediate issuer |
2995 | * of the leaf certificate is not a trust anchor. No attempt will be |
2996 | * made to locate an issuer for that certificate, since such a chain |
2997 | * would be a-priori too long. |
2998 | */ |
2999 | if ((search & S_DOTRUSTED) != 0) { |
3000 | i = num = sk_X509_num(ctx->chain); |
3001 | if ((search & S_DOALTERNATE) != 0) { |
3002 | /* |
3003 | * As high up the chain as we can, look for an alternative |
3004 | * trusted issuer of an untrusted certificate that currently |
3005 | * has an untrusted issuer. We use the alt_untrusted variable |
3006 | * to track how far up the chain we find the first match. It |
3007 | * is only if and when we find a match, that we prune the chain |
3008 | * and reset ctx->num_untrusted to the reduced count of |
3009 | * untrusted certificates. While we're searching for such a |
3010 | * match (which may never be found), it is neither safe nor |
3011 | * wise to preemptively modify either the chain or |
3012 | * ctx->num_untrusted. |
3013 | * |
3014 | * Note, like ctx->num_untrusted, alt_untrusted is a count of |
3015 | * untrusted certificates, not a "depth". |
3016 | */ |
3017 | i = alt_untrusted; |
3018 | } |
3019 | x = sk_X509_value(ctx->chain, i-1); |
3020 | |
3021 | ok = (depth < num) ? 0 : get_issuer(&xtmp, ctx, x); |
3022 | |
3023 | if (ok < 0) { |
3024 | trust = X509_TRUST_REJECTED; |
3025 | ctx->error = X509_V_ERR_STORE_LOOKUP; |
3026 | search = 0; |
3027 | continue; |
3028 | } |
3029 | |
3030 | if (ok > 0) { |
3031 | /* |
3032 | * Alternative trusted issuer for a mid-chain untrusted cert? |
3033 | * Pop the untrusted cert's successors and retry. We might now |
3034 | * be able to complete a valid chain via the trust store. Note |
3035 | * that despite the current trust-store match we might still |
3036 | * fail complete the chain to a suitable trust-anchor, in which |
3037 | * case we may prune some more untrusted certificates and try |
3038 | * again. Thus the S_DOALTERNATE bit may yet be turned on |
3039 | * again with an even shorter untrusted chain! |
3040 | * |
3041 | * If in the process we threw away our matching PKIX-TA trust |
3042 | * anchor, reset DANE trust. We might find a suitable trusted |
3043 | * certificate among the ones from the trust store. |
3044 | */ |
3045 | if ((search & S_DOALTERNATE) != 0) { |
3046 | if (!ossl_assert(num > i && i > 0 && ss == 0)) { |
3047 | X509err(X509_F_BUILD_CHAIN, ERR_R_INTERNAL_ERROR); |
3048 | X509_free(xtmp); |
3049 | trust = X509_TRUST_REJECTED; |
3050 | ctx->error = X509_V_ERR_UNSPECIFIED; |
3051 | search = 0; |
3052 | continue; |
3053 | } |
3054 | search &= ~S_DOALTERNATE; |
3055 | for (; num > i; --num) |
3056 | X509_free(sk_X509_pop(ctx->chain)); |
3057 | ctx->num_untrusted = num; |
3058 | |
3059 | if (DANETLS_ENABLED(dane) && |
3060 | dane->mdpth >= ctx->num_untrusted) { |
3061 | dane->mdpth = -1; |
3062 | X509_free(dane->mcert); |
3063 | dane->mcert = NULL; |
3064 | } |
3065 | if (DANETLS_ENABLED(dane) && |
3066 | dane->pdpth >= ctx->num_untrusted) |
3067 | dane->pdpth = -1; |
3068 | } |
3069 | |
3070 | /* |
3071 | * Self-signed untrusted certificates get replaced by their |
3072 | * trusted matching issuer. Otherwise, grow the chain. |
3073 | */ |
3074 | if (ss == 0) { |
3075 | if (!sk_X509_push(ctx->chain, x = xtmp)) { |
3076 | X509_free(xtmp); |
3077 | X509err(X509_F_BUILD_CHAIN, ERR_R_MALLOC_FAILURE); |
3078 | trust = X509_TRUST_REJECTED; |
3079 | ctx->error = X509_V_ERR_OUT_OF_MEM; |
3080 | search = 0; |
3081 | continue; |
3082 | } |
3083 | ss = cert_self_signed(x); |
3084 | } else if (num == ctx->num_untrusted) { |
3085 | /* |
3086 | * We have a self-signed certificate that has the same |
3087 | * subject name (and perhaps keyid and/or serial number) as |
3088 | * a trust-anchor. We must have an exact match to avoid |
3089 | * possible impersonation via key substitution etc. |
3090 | */ |
3091 | if (X509_cmp(x, xtmp) != 0) { |
3092 | /* Self-signed untrusted mimic. */ |
3093 | X509_free(xtmp); |
3094 | ok = 0; |
3095 | } else { |
3096 | X509_free(x); |
3097 | ctx->num_untrusted = --num; |
3098 | (void) sk_X509_set(ctx->chain, num, x = xtmp); |
3099 | } |
3100 | } |
3101 | |
3102 | /* |
3103 | * We've added a new trusted certificate to the chain, recheck |
3104 | * trust. If not done, and not self-signed look deeper. |
3105 | * Whether or not we're doing "trusted first", we no longer |
3106 | * look for untrusted certificates from the peer's chain. |
3107 | * |
3108 | * At this point ctx->num_trusted and num must reflect the |
3109 | * correct number of untrusted certificates, since the DANE |
3110 | * logic in check_trust() depends on distinguishing CAs from |
3111 | * "the wire" from CAs from the trust store. In particular, the |
3112 | * certificate at depth "num" should be the new trusted |
3113 | * certificate with ctx->num_untrusted <= num. |
3114 | */ |
3115 | if (ok) { |
3116 | if (!ossl_assert(ctx->num_untrusted <= num)) { |
3117 | X509err(X509_F_BUILD_CHAIN, ERR_R_INTERNAL_ERROR); |
3118 | trust = X509_TRUST_REJECTED; |
3119 | ctx->error = X509_V_ERR_UNSPECIFIED; |
3120 | search = 0; |
3121 | continue; |
3122 | } |
3123 | search &= ~S_DOUNTRUSTED; |
3124 | switch (trust = check_trust(ctx, num)) { |
3125 | case X509_TRUST_TRUSTED: |
3126 | case X509_TRUST_REJECTED: |
3127 | search = 0; |
3128 | continue; |
3129 | } |
3130 | if (ss == 0) |
3131 | continue; |
3132 | } |
3133 | } |
3134 | |
3135 | /* |
3136 | * No dispositive decision, and either self-signed or no match, if |
3137 | * we were doing untrusted-first, and alt-chains are not disabled, |
3138 | * do that, by repeatedly losing one untrusted element at a time, |
3139 | * and trying to extend the shorted chain. |
3140 | */ |
3141 | if ((search & S_DOUNTRUSTED) == 0) { |
3142 | /* Continue search for a trusted issuer of a shorter chain? */ |
3143 | if ((search & S_DOALTERNATE) != 0 && --alt_untrusted > 0) |
3144 | continue; |
3145 | /* Still no luck and no fallbacks left? */ |
3146 | if (!may_alternate || (search & S_DOALTERNATE) != 0 || |
3147 | ctx->num_untrusted < 2) |
3148 | break; |
3149 | /* Search for a trusted issuer of a shorter chain */ |
3150 | search |= S_DOALTERNATE; |
3151 | alt_untrusted = ctx->num_untrusted - 1; |
3152 | ss = 0; |
3153 | } |
3154 | } |
3155 | |
3156 | /* |
3157 | * Extend chain with peer-provided certificates |
3158 | */ |
3159 | if ((search & S_DOUNTRUSTED) != 0) { |
3160 | num = sk_X509_num(ctx->chain); |
3161 | if (!ossl_assert(num == ctx->num_untrusted)) { |
3162 | X509err(X509_F_BUILD_CHAIN, ERR_R_INTERNAL_ERROR); |
3163 | trust = X509_TRUST_REJECTED; |
3164 | ctx->error = X509_V_ERR_UNSPECIFIED; |
3165 | search = 0; |
3166 | continue; |
3167 | } |
3168 | x = sk_X509_value(ctx->chain, num-1); |
3169 | |
3170 | /* |
3171 | * Once we run out of untrusted issuers, we stop looking for more |
3172 | * and start looking only in the trust store if enabled. |
3173 | */ |
3174 | xtmp = (ss || depth < num) ? NULL : find_issuer(ctx, sktmp, x); |
3175 | if (xtmp == NULL) { |
3176 | search &= ~S_DOUNTRUSTED; |
3177 | if (may_trusted) |
3178 | search |= S_DOTRUSTED; |
3179 | continue; |
3180 | } |
3181 | |
3182 | /* Drop this issuer from future consideration */ |
3183 | (void) sk_X509_delete_ptr(sktmp, xtmp); |
3184 | |
3185 | if (!sk_X509_push(ctx->chain, xtmp)) { |
3186 | X509err(X509_F_BUILD_CHAIN, ERR_R_MALLOC_FAILURE); |
3187 | trust = X509_TRUST_REJECTED; |
3188 | ctx->error = X509_V_ERR_OUT_OF_MEM; |
3189 | search = 0; |
3190 | continue; |
3191 | } |
3192 | |
3193 | X509_up_ref(x = xtmp); |
3194 | ++ctx->num_untrusted; |
3195 | ss = cert_self_signed(xtmp); |
3196 | |
3197 | /* |
3198 | * Check for DANE-TA trust of the topmost untrusted certificate. |
3199 | */ |
3200 | switch (trust = check_dane_issuer(ctx, ctx->num_untrusted - 1)) { |
3201 | case X509_TRUST_TRUSTED: |
3202 | case X509_TRUST_REJECTED: |
3203 | search = 0; |
3204 | continue; |
3205 | } |
3206 | } |
3207 | } |
3208 | sk_X509_free(sktmp); |
3209 | |
3210 | /* |
3211 | * Last chance to make a trusted chain, either bare DANE-TA public-key |
3212 | * signers, or else direct leaf PKIX trust. |
3213 | */ |
3214 | num = sk_X509_num(ctx->chain); |
3215 | if (num <= depth) { |
3216 | if (trust == X509_TRUST_UNTRUSTED && DANETLS_HAS_DANE_TA(dane)) |
3217 | trust = check_dane_pkeys(ctx); |
3218 | if (trust == X509_TRUST_UNTRUSTED && num == ctx->num_untrusted) |
3219 | trust = check_trust(ctx, num); |
3220 | } |
3221 | |
3222 | switch (trust) { |
3223 | case X509_TRUST_TRUSTED: |
3224 | return 1; |
3225 | case X509_TRUST_REJECTED: |
3226 | /* Callback already issued */ |
3227 | return 0; |
3228 | case X509_TRUST_UNTRUSTED: |
3229 | default: |
3230 | num = sk_X509_num(ctx->chain); |
3231 | if (num > depth) |
3232 | return verify_cb_cert(ctx, NULL, num-1, |
3233 | X509_V_ERR_CERT_CHAIN_TOO_LONG); |
3234 | if (DANETLS_ENABLED(dane) && |
3235 | (!DANETLS_HAS_PKIX(dane) || dane->pdpth >= 0)) |
3236 | return verify_cb_cert(ctx, NULL, num-1, X509_V_ERR_DANE_NO_MATCH); |
3237 | if (ss && sk_X509_num(ctx->chain) == 1) |
3238 | return verify_cb_cert(ctx, NULL, num-1, |
3239 | X509_V_ERR_DEPTH_ZERO_SELF_SIGNED_CERT); |
3240 | if (ss) |
3241 | return verify_cb_cert(ctx, NULL, num-1, |
3242 | X509_V_ERR_SELF_SIGNED_CERT_IN_CHAIN); |
3243 | if (ctx->num_untrusted < num) |
3244 | return verify_cb_cert(ctx, NULL, num-1, |
3245 | X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT); |
3246 | return verify_cb_cert(ctx, NULL, num-1, |
3247 | X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT_LOCALLY); |
3248 | } |
3249 | } |
3250 | |
3251 | static const int minbits_table[] = { 80, 112, 128, 192, 256 }; |
3252 | static const int NUM_AUTH_LEVELS = OSSL_NELEM(minbits_table); |
3253 | |
3254 | /* |
3255 | * Check whether the public key of ``cert`` meets the security level of |
3256 | * ``ctx``. |
3257 | * |
3258 | * Returns 1 on success, 0 otherwise. |
3259 | */ |
3260 | static int check_key_level(X509_STORE_CTX *ctx, X509 *cert) |
3261 | { |
3262 | EVP_PKEY *pkey = X509_get0_pubkey(cert); |
3263 | int level = ctx->param->auth_level; |
3264 | |
3265 | /* |
3266 | * At security level zero, return without checking for a supported public |
3267 | * key type. Some engines support key types not understood outside the |
3268 | * engine, and we only need to understand the key when enforcing a security |
3269 | * floor. |
3270 | */ |
3271 | if (level <= 0) |
3272 | return 1; |
3273 | |
3274 | /* Unsupported or malformed keys are not secure */ |
3275 | if (pkey == NULL) |
3276 | return 0; |
3277 | |
3278 | if (level > NUM_AUTH_LEVELS) |
3279 | level = NUM_AUTH_LEVELS; |
3280 | |
3281 | return EVP_PKEY_security_bits(pkey) >= minbits_table[level - 1]; |
3282 | } |
3283 | |
3284 | /* |
3285 | * Check whether the signature digest algorithm of ``cert`` meets the security |
3286 | * level of ``ctx``. Should not be checked for trust anchors (whether |
3287 | * self-signed or otherwise). |
3288 | * |
3289 | * Returns 1 on success, 0 otherwise. |
3290 | */ |
3291 | static int check_sig_level(X509_STORE_CTX *ctx, X509 *cert) |
3292 | { |
3293 | int secbits = -1; |
3294 | int level = ctx->param->auth_level; |
3295 | |
3296 | if (level <= 0) |
3297 | return 1; |
3298 | if (level > NUM_AUTH_LEVELS) |
3299 | level = NUM_AUTH_LEVELS; |
3300 | |
3301 | if (!X509_get_signature_info(cert, NULL, NULL, &secbits, NULL)) |
3302 | return 0; |
3303 | |
3304 | return secbits >= minbits_table[level - 1]; |
3305 | } |
3306 | |