]>
Commit | Line | Data |
---|---|---|
0d2cd476 LP |
1 | /*** |
2 | This file is part of systemd. | |
3 | ||
4 | Copyright 2015 Lennart Poettering | |
5 | ||
6 | systemd is free software; you can redistribute it and/or modify it | |
7 | under the terms of the GNU Lesser General Public License as published by | |
8 | the Free Software Foundation; either version 2.1 of the License, or | |
9 | (at your option) any later version. | |
10 | ||
11 | systemd is distributed in the hope that it will be useful, but | |
12 | WITHOUT ANY WARRANTY; without even the implied warranty of | |
13 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
14 | Lesser General Public License for more details. | |
15 | ||
16 | You should have received a copy of the GNU Lesser General Public License | |
17 | along with systemd; If not, see <http://www.gnu.org/licenses/>. | |
18 | ***/ | |
19 | ||
62cc1c55 | 20 | #include "sd-messages.h" |
0c857028 | 21 | |
0d2cd476 | 22 | #include "alloc-util.h" |
8e54f5d9 LP |
23 | #include "conf-files.h" |
24 | #include "def.h" | |
25 | #include "dns-domain.h" | |
26 | #include "fd-util.h" | |
27 | #include "fileio.h" | |
28 | #include "hexdecoct.h" | |
29 | #include "parse-util.h" | |
0d2cd476 | 30 | #include "resolved-dns-trust-anchor.h" |
0c857028 | 31 | #include "resolved-dns-dnssec.h" |
8e54f5d9 LP |
32 | #include "set.h" |
33 | #include "string-util.h" | |
34 | #include "strv.h" | |
0d2cd476 | 35 | |
e7d179ac | 36 | static const char trust_anchor_dirs[] = CONF_PATHS_NULSTR("dnssec-trust-anchors.d"); |
8e54f5d9 | 37 | |
3401f0e1 LP |
38 | /* The first DS RR from https://data.iana.org/root-anchors/root-anchors.xml, retrieved December 2015 */ |
39 | static const uint8_t root_digest1[] = | |
0d2cd476 LP |
40 | { 0x49, 0xAA, 0xC1, 0x1D, 0x7B, 0x6F, 0x64, 0x46, 0x70, 0x2E, 0x54, 0xA1, 0x60, 0x73, 0x71, 0x60, |
41 | 0x7A, 0x1A, 0x41, 0x85, 0x52, 0x00, 0xFD, 0x2C, 0xE1, 0xCD, 0xDE, 0x32, 0xF2, 0x4E, 0x8F, 0xB5 }; | |
42 | ||
3401f0e1 LP |
43 | /* The second DS RR from https://data.iana.org/root-anchors/root-anchors.xml, retrieved February 2017 */ |
44 | static const uint8_t root_digest2[] = | |
45 | { 0xE0, 0x6D, 0x44, 0xB8, 0x0B, 0x8F, 0x1D, 0x39, 0xA9, 0x5C, 0x0B, 0x0D, 0x7C, 0x65, 0xD0, 0x84, | |
46 | 0x58, 0xE8, 0x80, 0x40, 0x9B, 0xBC, 0x68, 0x34, 0x57, 0x10, 0x42, 0x37, 0xC7, 0xF8, 0xEC, 0x8D }; | |
47 | ||
86e9cbca LP |
48 | static bool dns_trust_anchor_knows_domain_positive(DnsTrustAnchor *d, const char *name) { |
49 | assert(d); | |
50 | ||
51 | /* Returns true if there's an entry for the specified domain | |
52 | * name in our trust anchor */ | |
53 | ||
54 | return | |
55 | hashmap_contains(d->positive_by_key, &DNS_RESOURCE_KEY_CONST(DNS_CLASS_IN, DNS_TYPE_DNSKEY, name)) || | |
56 | hashmap_contains(d->positive_by_key, &DNS_RESOURCE_KEY_CONST(DNS_CLASS_IN, DNS_TYPE_DS, name)); | |
57 | } | |
58 | ||
3401f0e1 LP |
59 | static int add_root_ksk( |
60 | DnsAnswer *answer, | |
61 | DnsResourceKey *key, | |
62 | uint16_t key_tag, | |
63 | uint8_t algorithm, | |
64 | uint8_t digest_type, | |
65 | const void *digest, | |
66 | size_t digest_size) { | |
67 | ||
0d2cd476 | 68 | _cleanup_(dns_resource_record_unrefp) DnsResourceRecord *rr = NULL; |
3401f0e1 LP |
69 | int r; |
70 | ||
71 | rr = dns_resource_record_new(key); | |
72 | if (!rr) | |
73 | return -ENOMEM; | |
74 | ||
75 | rr->ds.key_tag = key_tag; | |
76 | rr->ds.algorithm = algorithm; | |
77 | rr->ds.digest_type = digest_type; | |
78 | rr->ds.digest_size = digest_size; | |
79 | rr->ds.digest = memdup(digest, rr->ds.digest_size); | |
80 | if (!rr->ds.digest) | |
81 | return -ENOMEM; | |
82 | ||
83 | r = dns_answer_add(answer, rr, 0, DNS_ANSWER_AUTHENTICATED); | |
84 | if (r < 0) | |
85 | return r; | |
86 | ||
87 | return 0; | |
88 | } | |
89 | ||
90 | static int dns_trust_anchor_add_builtin_positive(DnsTrustAnchor *d) { | |
0d2cd476 | 91 | _cleanup_(dns_answer_unrefp) DnsAnswer *answer = NULL; |
3401f0e1 | 92 | _cleanup_(dns_resource_key_unrefp) DnsResourceKey *key = NULL; |
0d2cd476 LP |
93 | int r; |
94 | ||
95 | assert(d); | |
96 | ||
8e54f5d9 | 97 | r = hashmap_ensure_allocated(&d->positive_by_key, &dns_resource_key_hash_ops); |
0d2cd476 LP |
98 | if (r < 0) |
99 | return r; | |
100 | ||
3401f0e1 LP |
101 | /* Only add the built-in trust anchor if there's neither a DS nor a DNSKEY defined for the root domain. That |
102 | * way users have an easy way to override the root domain DS/DNSKEY data. */ | |
86e9cbca | 103 | if (dns_trust_anchor_knows_domain_positive(d, ".")) |
d76f90f1 LP |
104 | return 0; |
105 | ||
3401f0e1 LP |
106 | key = dns_resource_key_new(DNS_CLASS_IN, DNS_TYPE_DS, ""); |
107 | if (!key) | |
0d2cd476 LP |
108 | return -ENOMEM; |
109 | ||
3401f0e1 | 110 | answer = dns_answer_new(2); |
0d2cd476 LP |
111 | if (!answer) |
112 | return -ENOMEM; | |
113 | ||
3401f0e1 LP |
114 | /* Add the two RRs from https://data.iana.org/root-anchors/root-anchors.xml */ |
115 | r = add_root_ksk(answer, key, 19036, DNSSEC_ALGORITHM_RSASHA256, DNSSEC_DIGEST_SHA256, root_digest1, sizeof(root_digest1)); | |
116 | if (r < 0) | |
117 | return r; | |
118 | ||
119 | r = add_root_ksk(answer, key, 20326, DNSSEC_ALGORITHM_RSASHA256, DNSSEC_DIGEST_SHA256, root_digest2, sizeof(root_digest2)); | |
0d2cd476 LP |
120 | if (r < 0) |
121 | return r; | |
122 | ||
3401f0e1 | 123 | r = hashmap_put(d->positive_by_key, key, answer); |
8e54f5d9 LP |
124 | if (r < 0) |
125 | return r; | |
126 | ||
127 | answer = NULL; | |
128 | return 0; | |
129 | } | |
130 | ||
30c77809 LP |
131 | static int dns_trust_anchor_add_builtin_negative(DnsTrustAnchor *d) { |
132 | ||
133 | static const char private_domains[] = | |
134 | /* RFC 6761 says that .test is a special domain for | |
135 | * testing and not to be installed in the root zone */ | |
136 | "test\0" | |
137 | ||
138 | /* RFC 6761 says that these reverse IP lookup ranges | |
139 | * are for private addresses, and hence should not | |
140 | * show up in the root zone */ | |
141 | "10.in-addr.arpa\0" | |
142 | "16.172.in-addr.arpa\0" | |
143 | "17.172.in-addr.arpa\0" | |
144 | "18.172.in-addr.arpa\0" | |
145 | "19.172.in-addr.arpa\0" | |
146 | "20.172.in-addr.arpa\0" | |
147 | "21.172.in-addr.arpa\0" | |
148 | "22.172.in-addr.arpa\0" | |
149 | "23.172.in-addr.arpa\0" | |
150 | "24.172.in-addr.arpa\0" | |
151 | "25.172.in-addr.arpa\0" | |
152 | "26.172.in-addr.arpa\0" | |
153 | "27.172.in-addr.arpa\0" | |
154 | "28.172.in-addr.arpa\0" | |
155 | "29.172.in-addr.arpa\0" | |
156 | "30.172.in-addr.arpa\0" | |
157 | "31.172.in-addr.arpa\0" | |
158 | "168.192.in-addr.arpa\0" | |
159 | ||
f07529fe LP |
160 | /* The same, but for IPv6. */ |
161 | "d.f.ip6.arpa\0" | |
162 | ||
30c77809 LP |
163 | /* RFC 6762 reserves the .local domain for Multicast |
164 | * DNS, it hence cannot appear in the root zone. (Note | |
165 | * that we by default do not route .local traffic to | |
166 | * DNS anyway, except when a configured search domain | |
167 | * suggests so.) */ | |
168 | "local\0" | |
169 | ||
170 | /* These two are well known, popular private zone | |
171 | * TLDs, that are blocked from delegation, according | |
172 | * to: | |
173 | * http://icannwiki.com/Name_Collision#NGPC_Resolution | |
174 | * | |
175 | * There's also ongoing work on making this official | |
176 | * in an RRC: | |
177 | * https://www.ietf.org/archive/id/draft-chapin-additional-reserved-tlds-02.txt */ | |
178 | "home\0" | |
179 | "corp\0" | |
180 | ||
181 | /* The following four TLDs are suggested for private | |
182 | * zones in RFC 6762, Appendix G, and are hence very | |
183 | * unlikely to be made official TLDs any day soon */ | |
184 | "lan\0" | |
185 | "intranet\0" | |
186 | "internal\0" | |
187 | "private\0"; | |
188 | ||
189 | const char *name; | |
190 | int r; | |
191 | ||
192 | assert(d); | |
193 | ||
194 | /* Only add the built-in trust anchor if there's no negative | |
195 | * trust anchor defined at all. This enables easy overriding | |
196 | * of negative trust anchors. */ | |
197 | ||
198 | if (set_size(d->negative_by_name) > 0) | |
199 | return 0; | |
200 | ||
201 | r = set_ensure_allocated(&d->negative_by_name, &dns_name_hash_ops); | |
202 | if (r < 0) | |
203 | return r; | |
204 | ||
205 | /* We add a couple of domains as default negative trust | |
206 | * anchors, where it's very unlikely they will be installed in | |
207 | * the root zone. If they exist they must be private, and thus | |
208 | * unsigned. */ | |
209 | ||
210 | NULSTR_FOREACH(name, private_domains) { | |
211 | ||
212 | if (dns_trust_anchor_knows_domain_positive(d, name)) | |
213 | continue; | |
214 | ||
215 | r = set_put_strdup(d->negative_by_name, name); | |
216 | if (r < 0) | |
217 | return r; | |
218 | } | |
219 | ||
220 | return 0; | |
221 | } | |
222 | ||
8e54f5d9 LP |
223 | static int dns_trust_anchor_load_positive(DnsTrustAnchor *d, const char *path, unsigned line, const char *s) { |
224 | _cleanup_(dns_resource_record_unrefp) DnsResourceRecord *rr = NULL; | |
225 | _cleanup_free_ char *domain = NULL, *class = NULL, *type = NULL; | |
226 | _cleanup_(dns_answer_unrefp) DnsAnswer *answer = NULL; | |
227 | DnsAnswer *old_answer = NULL; | |
228 | const char *p = s; | |
229 | int r; | |
230 | ||
231 | assert(d); | |
232 | assert(line); | |
233 | ||
234 | r = extract_first_word(&p, &domain, NULL, EXTRACT_QUOTES); | |
235 | if (r < 0) | |
236 | return log_warning_errno(r, "Unable to parse domain in line %s:%u: %m", path, line); | |
237 | ||
238 | if (!dns_name_is_valid(domain)) { | |
239 | log_warning("Domain name %s is invalid, at line %s:%u, ignoring line.", domain, path, line); | |
240 | return -EINVAL; | |
241 | } | |
242 | ||
243 | r = extract_many_words(&p, NULL, 0, &class, &type, NULL); | |
244 | if (r < 0) | |
245 | return log_warning_errno(r, "Unable to parse class and type in line %s:%u: %m", path, line); | |
246 | if (r != 2) { | |
247 | log_warning("Missing class or type in line %s:%u", path, line); | |
248 | return -EINVAL; | |
249 | } | |
250 | ||
251 | if (!strcaseeq(class, "IN")) { | |
252 | log_warning("RR class %s is not supported, ignoring line %s:%u.", class, path, line); | |
253 | return -EINVAL; | |
254 | } | |
255 | ||
256 | if (strcaseeq(type, "DS")) { | |
257 | _cleanup_free_ char *key_tag = NULL, *algorithm = NULL, *digest_type = NULL, *digest = NULL; | |
258 | _cleanup_free_ void *dd = NULL; | |
259 | uint16_t kt; | |
260 | int a, dt; | |
261 | size_t l; | |
262 | ||
263 | r = extract_many_words(&p, NULL, 0, &key_tag, &algorithm, &digest_type, &digest, NULL); | |
264 | if (r < 0) { | |
265 | log_warning_errno(r, "Failed to parse DS parameters on line %s:%u: %m", path, line); | |
266 | return -EINVAL; | |
267 | } | |
268 | if (r != 4) { | |
269 | log_warning("Missing DS parameters on line %s:%u", path, line); | |
270 | return -EINVAL; | |
271 | } | |
272 | ||
273 | r = safe_atou16(key_tag, &kt); | |
274 | if (r < 0) | |
275 | return log_warning_errno(r, "Failed to parse DS key tag %s on line %s:%u: %m", key_tag, path, line); | |
276 | ||
277 | a = dnssec_algorithm_from_string(algorithm); | |
278 | if (a < 0) { | |
279 | log_warning("Failed to parse DS algorithm %s on line %s:%u", algorithm, path, line); | |
280 | return -EINVAL; | |
281 | } | |
282 | ||
283 | dt = dnssec_digest_from_string(digest_type); | |
284 | if (dt < 0) { | |
285 | log_warning("Failed to parse DS digest type %s on line %s:%u", digest_type, path, line); | |
286 | return -EINVAL; | |
287 | } | |
288 | ||
289 | r = unhexmem(digest, strlen(digest), &dd, &l); | |
290 | if (r < 0) { | |
291 | log_warning("Failed to parse DS digest %s on line %s:%u", digest, path, line); | |
292 | return -EINVAL; | |
293 | } | |
294 | ||
295 | rr = dns_resource_record_new_full(DNS_CLASS_IN, DNS_TYPE_DS, domain); | |
296 | if (!rr) | |
297 | return log_oom(); | |
298 | ||
299 | rr->ds.key_tag = kt; | |
300 | rr->ds.algorithm = a; | |
301 | rr->ds.digest_type = dt; | |
302 | rr->ds.digest_size = l; | |
303 | rr->ds.digest = dd; | |
304 | dd = NULL; | |
305 | ||
306 | } else if (strcaseeq(type, "DNSKEY")) { | |
307 | _cleanup_free_ char *flags = NULL, *protocol = NULL, *algorithm = NULL, *key = NULL; | |
308 | _cleanup_free_ void *k = NULL; | |
309 | uint16_t f; | |
310 | size_t l; | |
311 | int a; | |
312 | ||
313 | r = extract_many_words(&p, NULL, 0, &flags, &protocol, &algorithm, &key, NULL); | |
314 | if (r < 0) | |
315 | return log_warning_errno(r, "Failed to parse DNSKEY parameters on line %s:%u: %m", path, line); | |
316 | if (r != 4) { | |
317 | log_warning("Missing DNSKEY parameters on line %s:%u", path, line); | |
318 | return -EINVAL; | |
319 | } | |
320 | ||
321 | if (!streq(protocol, "3")) { | |
322 | log_warning("DNSKEY Protocol is not 3 on line %s:%u", path, line); | |
323 | return -EINVAL; | |
324 | } | |
325 | ||
326 | r = safe_atou16(flags, &f); | |
327 | if (r < 0) | |
328 | return log_warning_errno(r, "Failed to parse DNSKEY flags field %s on line %s:%u", flags, path, line); | |
2a0d751b LP |
329 | if ((f & DNSKEY_FLAG_ZONE_KEY) == 0) { |
330 | log_warning("DNSKEY lacks zone key bit set on line %s:%u", path, line); | |
331 | return -EINVAL; | |
332 | } | |
333 | if ((f & DNSKEY_FLAG_REVOKE)) { | |
334 | log_warning("DNSKEY is already revoked on line %s:%u", path, line); | |
335 | return -EINVAL; | |
336 | } | |
8e54f5d9 LP |
337 | |
338 | a = dnssec_algorithm_from_string(algorithm); | |
339 | if (a < 0) { | |
340 | log_warning("Failed to parse DNSKEY algorithm %s on line %s:%u", algorithm, path, line); | |
341 | return -EINVAL; | |
342 | } | |
343 | ||
344 | r = unbase64mem(key, strlen(key), &k, &l); | |
345 | if (r < 0) | |
346 | return log_warning_errno(r, "Failed to parse DNSKEY key data %s on line %s:%u", key, path, line); | |
347 | ||
348 | rr = dns_resource_record_new_full(DNS_CLASS_IN, DNS_TYPE_DNSKEY, domain); | |
349 | if (!rr) | |
350 | return log_oom(); | |
351 | ||
352 | rr->dnskey.flags = f; | |
353 | rr->dnskey.protocol = 3; | |
354 | rr->dnskey.algorithm = a; | |
355 | rr->dnskey.key_size = l; | |
356 | rr->dnskey.key = k; | |
357 | k = NULL; | |
358 | ||
359 | } else { | |
360 | log_warning("RR type %s is not supported, ignoring line %s:%u.", type, path, line); | |
361 | return -EINVAL; | |
362 | } | |
363 | ||
364 | if (!isempty(p)) { | |
365 | log_warning("Trailing garbage on line %s:%u, ignoring line.", path, line); | |
366 | return -EINVAL; | |
367 | } | |
368 | ||
369 | r = hashmap_ensure_allocated(&d->positive_by_key, &dns_resource_key_hash_ops); | |
0d2cd476 | 370 | if (r < 0) |
b3331c39 | 371 | return log_oom(); |
0d2cd476 | 372 | |
8e54f5d9 LP |
373 | old_answer = hashmap_get(d->positive_by_key, rr->key); |
374 | answer = dns_answer_ref(old_answer); | |
375 | ||
376 | r = dns_answer_add_extend(&answer, rr, 0, DNS_ANSWER_AUTHENTICATED); | |
377 | if (r < 0) | |
378 | return log_error_errno(r, "Failed to add trust anchor RR: %m"); | |
379 | ||
380 | r = hashmap_replace(d->positive_by_key, rr->key, answer); | |
381 | if (r < 0) | |
382 | return log_error_errno(r, "Failed to add answer to trust anchor: %m"); | |
383 | ||
384 | old_answer = dns_answer_unref(old_answer); | |
0d2cd476 | 385 | answer = NULL; |
8e54f5d9 LP |
386 | |
387 | return 0; | |
388 | } | |
389 | ||
390 | static int dns_trust_anchor_load_negative(DnsTrustAnchor *d, const char *path, unsigned line, const char *s) { | |
391 | _cleanup_free_ char *domain = NULL; | |
392 | const char *p = s; | |
393 | int r; | |
394 | ||
395 | assert(d); | |
396 | assert(line); | |
397 | ||
398 | r = extract_first_word(&p, &domain, NULL, EXTRACT_QUOTES); | |
399 | if (r < 0) | |
400 | return log_warning_errno(r, "Unable to parse line %s:%u: %m", path, line); | |
401 | ||
402 | if (!dns_name_is_valid(domain)) { | |
403 | log_warning("Domain name %s is invalid, at line %s:%u, ignoring line.", domain, path, line); | |
404 | return -EINVAL; | |
405 | } | |
406 | ||
407 | if (!isempty(p)) { | |
408 | log_warning("Trailing garbage at line %s:%u, ignoring line.", path, line); | |
409 | return -EINVAL; | |
410 | } | |
411 | ||
412 | r = set_ensure_allocated(&d->negative_by_name, &dns_name_hash_ops); | |
413 | if (r < 0) | |
b3331c39 | 414 | return log_oom(); |
8e54f5d9 LP |
415 | |
416 | r = set_put(d->negative_by_name, domain); | |
417 | if (r < 0) | |
418 | return log_oom(); | |
419 | if (r > 0) | |
420 | domain = NULL; | |
421 | ||
422 | return 0; | |
423 | } | |
424 | ||
425 | static int dns_trust_anchor_load_files( | |
426 | DnsTrustAnchor *d, | |
427 | const char *suffix, | |
428 | int (*loader)(DnsTrustAnchor *d, const char *path, unsigned n, const char *line)) { | |
429 | ||
430 | _cleanup_strv_free_ char **files = NULL; | |
431 | char **f; | |
432 | int r; | |
433 | ||
434 | assert(d); | |
435 | assert(suffix); | |
436 | assert(loader); | |
437 | ||
b5084605 | 438 | r = conf_files_list_nulstr(&files, suffix, NULL, 0, trust_anchor_dirs); |
8e54f5d9 LP |
439 | if (r < 0) |
440 | return log_error_errno(r, "Failed to enumerate %s trust anchor files: %m", suffix); | |
441 | ||
442 | STRV_FOREACH(f, files) { | |
443 | _cleanup_fclose_ FILE *g = NULL; | |
444 | char line[LINE_MAX]; | |
445 | unsigned n = 0; | |
446 | ||
447 | g = fopen(*f, "r"); | |
448 | if (!g) { | |
449 | if (errno == ENOENT) | |
450 | continue; | |
451 | ||
452 | log_warning_errno(errno, "Failed to open %s: %m", *f); | |
453 | continue; | |
454 | } | |
455 | ||
456 | FOREACH_LINE(line, g, log_warning_errno(errno, "Failed to read %s, ignoring: %m", *f)) { | |
457 | char *l; | |
458 | ||
459 | n++; | |
460 | ||
461 | l = strstrip(line); | |
462 | if (isempty(l)) | |
463 | continue; | |
464 | ||
465 | if (*l == ';') | |
466 | continue; | |
467 | ||
468 | (void) loader(d, *f, n, l); | |
469 | } | |
470 | } | |
471 | ||
472 | return 0; | |
473 | } | |
474 | ||
bec69050 LP |
475 | static int domain_name_cmp(const void *a, const void *b) { |
476 | char **x = (char**) a, **y = (char**) b; | |
477 | ||
478 | return dns_name_compare_func(*x, *y); | |
479 | } | |
480 | ||
481 | static int dns_trust_anchor_dump(DnsTrustAnchor *d) { | |
8e54f5d9 LP |
482 | DnsAnswer *a; |
483 | Iterator i; | |
484 | ||
485 | assert(d); | |
486 | ||
105f6c4b LP |
487 | if (hashmap_isempty(d->positive_by_key)) |
488 | log_info("No positive trust anchors defined."); | |
489 | else { | |
490 | log_info("Positive Trust Anchors:"); | |
491 | HASHMAP_FOREACH(a, d->positive_by_key, i) { | |
492 | DnsResourceRecord *rr; | |
493 | ||
494 | DNS_ANSWER_FOREACH(rr, a) | |
495 | log_info("%s", dns_resource_record_to_string(rr)); | |
496 | } | |
8e54f5d9 LP |
497 | } |
498 | ||
105f6c4b LP |
499 | if (set_isempty(d->negative_by_name)) |
500 | log_info("No negative trust anchors defined."); | |
501 | else { | |
bec69050 LP |
502 | _cleanup_free_ char **l = NULL, *j = NULL; |
503 | ||
504 | l = set_get_strv(d->negative_by_name); | |
505 | if (!l) | |
506 | return log_oom(); | |
8e54f5d9 | 507 | |
bec69050 LP |
508 | qsort_safe(l, set_size(d->negative_by_name), sizeof(char*), domain_name_cmp); |
509 | ||
510 | j = strv_join(l, " "); | |
511 | if (!j) | |
512 | return log_oom(); | |
513 | ||
514 | log_info("Negative trust anchors: %s", j); | |
8e54f5d9 | 515 | } |
bec69050 LP |
516 | |
517 | return 0; | |
8e54f5d9 LP |
518 | } |
519 | ||
520 | int dns_trust_anchor_load(DnsTrustAnchor *d) { | |
521 | int r; | |
522 | ||
523 | assert(d); | |
524 | ||
525 | /* If loading things from disk fails, we don't consider this fatal */ | |
526 | (void) dns_trust_anchor_load_files(d, ".positive", dns_trust_anchor_load_positive); | |
527 | (void) dns_trust_anchor_load_files(d, ".negative", dns_trust_anchor_load_negative); | |
528 | ||
529 | /* However, if the built-in DS fails, then we have a problem. */ | |
30c77809 LP |
530 | r = dns_trust_anchor_add_builtin_positive(d); |
531 | if (r < 0) | |
532 | return log_error_errno(r, "Failed to add built-in positive trust anchor: %m"); | |
533 | ||
534 | r = dns_trust_anchor_add_builtin_negative(d); | |
8e54f5d9 | 535 | if (r < 0) |
30c77809 | 536 | return log_error_errno(r, "Failed to add built-in negative trust anchor: %m"); |
8e54f5d9 LP |
537 | |
538 | dns_trust_anchor_dump(d); | |
539 | ||
0d2cd476 LP |
540 | return 0; |
541 | } | |
542 | ||
543 | void dns_trust_anchor_flush(DnsTrustAnchor *d) { | |
544 | DnsAnswer *a; | |
c9c72065 | 545 | DnsResourceRecord *rr; |
0d2cd476 LP |
546 | |
547 | assert(d); | |
548 | ||
8e54f5d9 | 549 | while ((a = hashmap_steal_first(d->positive_by_key))) |
0d2cd476 | 550 | dns_answer_unref(a); |
8e54f5d9 | 551 | d->positive_by_key = hashmap_free(d->positive_by_key); |
c9c72065 LP |
552 | |
553 | while ((rr = set_steal_first(d->revoked_by_rr))) | |
554 | dns_resource_record_unref(rr); | |
555 | d->revoked_by_rr = set_free(d->revoked_by_rr); | |
556 | ||
8e54f5d9 | 557 | d->negative_by_name = set_free_free(d->negative_by_name); |
0d2cd476 LP |
558 | } |
559 | ||
8e54f5d9 | 560 | int dns_trust_anchor_lookup_positive(DnsTrustAnchor *d, const DnsResourceKey *key, DnsAnswer **ret) { |
0d2cd476 LP |
561 | DnsAnswer *a; |
562 | ||
563 | assert(d); | |
564 | assert(key); | |
565 | assert(ret); | |
566 | ||
567 | /* We only serve DS and DNSKEY RRs. */ | |
568 | if (!IN_SET(key->type, DNS_TYPE_DS, DNS_TYPE_DNSKEY)) | |
569 | return 0; | |
570 | ||
8e54f5d9 | 571 | a = hashmap_get(d->positive_by_key, key); |
0d2cd476 LP |
572 | if (!a) |
573 | return 0; | |
574 | ||
575 | *ret = dns_answer_ref(a); | |
576 | return 1; | |
577 | } | |
8e54f5d9 LP |
578 | |
579 | int dns_trust_anchor_lookup_negative(DnsTrustAnchor *d, const char *name) { | |
c775838a LP |
580 | int r; |
581 | ||
8e54f5d9 LP |
582 | assert(d); |
583 | assert(name); | |
584 | ||
c775838a LP |
585 | for (;;) { |
586 | /* If the domain is listed as-is in the NTA database, then that counts */ | |
587 | if (set_contains(d->negative_by_name, name)) | |
588 | return true; | |
589 | ||
590 | /* If the domain isn't listed as NTA, but is listed as positive trust anchor, then that counts. See RFC | |
591 | * 7646, section 1.1 */ | |
592 | if (hashmap_contains(d->positive_by_key, &DNS_RESOURCE_KEY_CONST(DNS_CLASS_IN, DNS_TYPE_DS, name))) | |
593 | return false; | |
594 | ||
595 | if (hashmap_contains(d->positive_by_key, &DNS_RESOURCE_KEY_CONST(DNS_CLASS_IN, DNS_TYPE_KEY, name))) | |
596 | return false; | |
597 | ||
598 | /* And now, let's look at the parent, and check that too */ | |
599 | r = dns_name_parent(&name); | |
600 | if (r < 0) | |
601 | return r; | |
602 | if (r == 0) | |
603 | break; | |
604 | } | |
605 | ||
606 | return false; | |
8e54f5d9 | 607 | } |
0c857028 | 608 | |
c9c72065 LP |
609 | static int dns_trust_anchor_revoked_put(DnsTrustAnchor *d, DnsResourceRecord *rr) { |
610 | int r; | |
611 | ||
612 | assert(d); | |
613 | ||
614 | r = set_ensure_allocated(&d->revoked_by_rr, &dns_resource_record_hash_ops); | |
615 | if (r < 0) | |
616 | return r; | |
617 | ||
618 | r = set_put(d->revoked_by_rr, rr); | |
619 | if (r < 0) | |
620 | return r; | |
621 | if (r > 0) | |
622 | dns_resource_record_ref(rr); | |
623 | ||
624 | return r; | |
625 | } | |
626 | ||
0c857028 LP |
627 | static int dns_trust_anchor_remove_revoked(DnsTrustAnchor *d, DnsResourceRecord *rr) { |
628 | _cleanup_(dns_answer_unrefp) DnsAnswer *new_answer = NULL; | |
629 | DnsAnswer *old_answer; | |
630 | int r; | |
631 | ||
c9c72065 LP |
632 | /* Remember that this is a revoked trust anchor RR */ |
633 | r = dns_trust_anchor_revoked_put(d, rr); | |
634 | if (r < 0) | |
635 | return r; | |
636 | ||
637 | /* Remove this from the positive trust anchor */ | |
0c857028 LP |
638 | old_answer = hashmap_get(d->positive_by_key, rr->key); |
639 | if (!old_answer) | |
640 | return 0; | |
641 | ||
642 | new_answer = dns_answer_ref(old_answer); | |
643 | ||
644 | r = dns_answer_remove_by_rr(&new_answer, rr); | |
645 | if (r <= 0) | |
646 | return r; | |
647 | ||
648 | /* We found the key! Warn the user */ | |
649 | log_struct(LOG_WARNING, | |
2b044526 | 650 | "MESSAGE_ID=" SD_MESSAGE_DNSSEC_TRUST_ANCHOR_REVOKED_STR, |
0c857028 LP |
651 | LOG_MESSAGE("DNSSEC Trust anchor %s has been revoked. Please update the trust anchor, or upgrade your operating system."), strna(dns_resource_record_to_string(rr)), |
652 | "TRUST_ANCHOR=%s", dns_resource_record_to_string(rr), | |
653 | NULL); | |
654 | ||
655 | if (dns_answer_size(new_answer) <= 0) { | |
656 | assert_se(hashmap_remove(d->positive_by_key, rr->key) == old_answer); | |
657 | dns_answer_unref(old_answer); | |
658 | return 1; | |
659 | } | |
660 | ||
661 | r = hashmap_replace(d->positive_by_key, new_answer->items[0].rr->key, new_answer); | |
662 | if (r < 0) | |
663 | return r; | |
664 | ||
665 | new_answer = NULL; | |
666 | dns_answer_unref(old_answer); | |
667 | return 1; | |
668 | } | |
669 | ||
670 | static int dns_trust_anchor_check_revoked_one(DnsTrustAnchor *d, DnsResourceRecord *revoked_dnskey) { | |
671 | DnsAnswer *a; | |
672 | int r; | |
673 | ||
674 | assert(d); | |
675 | assert(revoked_dnskey); | |
676 | assert(revoked_dnskey->key->type == DNS_TYPE_DNSKEY); | |
677 | assert(revoked_dnskey->dnskey.flags & DNSKEY_FLAG_REVOKE); | |
678 | ||
679 | a = hashmap_get(d->positive_by_key, revoked_dnskey->key); | |
680 | if (a) { | |
681 | DnsResourceRecord *anchor; | |
682 | ||
683 | /* First, look for the precise DNSKEY in our trust anchor database */ | |
684 | ||
685 | DNS_ANSWER_FOREACH(anchor, a) { | |
686 | ||
687 | if (anchor->dnskey.protocol != revoked_dnskey->dnskey.protocol) | |
688 | continue; | |
689 | ||
690 | if (anchor->dnskey.algorithm != revoked_dnskey->dnskey.algorithm) | |
691 | continue; | |
692 | ||
693 | if (anchor->dnskey.key_size != revoked_dnskey->dnskey.key_size) | |
694 | continue; | |
695 | ||
c9c72065 LP |
696 | /* Note that we allow the REVOKE bit to be |
697 | * different! It will be set in the revoked | |
698 | * key, but unset in our version of it */ | |
0c857028 LP |
699 | if (((anchor->dnskey.flags ^ revoked_dnskey->dnskey.flags) | DNSKEY_FLAG_REVOKE) != DNSKEY_FLAG_REVOKE) |
700 | continue; | |
701 | ||
702 | if (memcmp(anchor->dnskey.key, revoked_dnskey->dnskey.key, anchor->dnskey.key_size) != 0) | |
703 | continue; | |
704 | ||
705 | dns_trust_anchor_remove_revoked(d, anchor); | |
706 | break; | |
707 | } | |
708 | } | |
709 | ||
1c02e7ba | 710 | a = hashmap_get(d->positive_by_key, &DNS_RESOURCE_KEY_CONST(revoked_dnskey->key->class, DNS_TYPE_DS, dns_resource_key_name(revoked_dnskey->key))); |
0c857028 LP |
711 | if (a) { |
712 | DnsResourceRecord *anchor; | |
713 | ||
714 | /* Second, look for DS RRs matching this DNSKEY in our trust anchor database */ | |
715 | ||
716 | DNS_ANSWER_FOREACH(anchor, a) { | |
717 | ||
c9c72065 LP |
718 | /* We set mask_revoke to true here, since our |
719 | * DS fingerprint will be the one of the | |
720 | * unrevoked DNSKEY, but the one we got passed | |
721 | * here has the bit set. */ | |
96bb7673 | 722 | r = dnssec_verify_dnskey_by_ds(revoked_dnskey, anchor, true); |
0c857028 LP |
723 | if (r < 0) |
724 | return r; | |
725 | if (r == 0) | |
726 | continue; | |
727 | ||
728 | dns_trust_anchor_remove_revoked(d, anchor); | |
729 | break; | |
730 | } | |
731 | } | |
732 | ||
733 | return 0; | |
734 | } | |
735 | ||
d424da2a LP |
736 | int dns_trust_anchor_check_revoked(DnsTrustAnchor *d, DnsResourceRecord *dnskey, DnsAnswer *rrs) { |
737 | DnsResourceRecord *rrsig; | |
0c857028 LP |
738 | int r; |
739 | ||
740 | assert(d); | |
d424da2a LP |
741 | assert(dnskey); |
742 | ||
743 | /* Looks if "dnskey" is a self-signed RR that has been revoked | |
744 | * and matches one of our trust anchor entries. If so, removes | |
745 | * it from the trust anchor and returns > 0. */ | |
0c857028 | 746 | |
d424da2a LP |
747 | if (dnskey->key->type != DNS_TYPE_DNSKEY) |
748 | return 0; | |
0c857028 | 749 | |
d424da2a LP |
750 | /* Is this DNSKEY revoked? */ |
751 | if ((dnskey->dnskey.flags & DNSKEY_FLAG_REVOKE) == 0) | |
0c857028 LP |
752 | return 0; |
753 | ||
d424da2a LP |
754 | /* Could this be interesting to us at all? If not, |
755 | * there's no point in looking for and verifying a | |
756 | * self-signed RRSIG. */ | |
1c02e7ba | 757 | if (!dns_trust_anchor_knows_domain_positive(d, dns_resource_key_name(dnskey->key))) |
d424da2a LP |
758 | return 0; |
759 | ||
760 | /* Look for a self-signed RRSIG in the other rrs belonging to this DNSKEY */ | |
761 | DNS_ANSWER_FOREACH(rrsig, rrs) { | |
0c857028 LP |
762 | DnssecResult result; |
763 | ||
d424da2a LP |
764 | if (rrsig->key->type != DNS_TYPE_RRSIG) |
765 | continue; | |
766 | ||
767 | r = dnssec_rrsig_match_dnskey(rrsig, dnskey, true); | |
0c857028 LP |
768 | if (r < 0) |
769 | return r; | |
770 | if (r == 0) | |
771 | continue; | |
772 | ||
d424da2a LP |
773 | r = dnssec_verify_rrset(rrs, dnskey->key, rrsig, dnskey, USEC_INFINITY, &result); |
774 | if (r < 0) | |
775 | return r; | |
776 | if (result != DNSSEC_VALIDATED) | |
0c857028 LP |
777 | continue; |
778 | ||
d424da2a LP |
779 | /* Bingo! This is a revoked self-signed DNSKEY. Let's |
780 | * see if this precise one exists in our trust anchor | |
781 | * database, too. */ | |
782 | r = dns_trust_anchor_check_revoked_one(d, dnskey); | |
783 | if (r < 0) | |
784 | return r; | |
0c857028 | 785 | |
d424da2a | 786 | return 1; |
0c857028 LP |
787 | } |
788 | ||
789 | return 0; | |
790 | } | |
c9c72065 LP |
791 | |
792 | int dns_trust_anchor_is_revoked(DnsTrustAnchor *d, DnsResourceRecord *rr) { | |
793 | assert(d); | |
794 | ||
795 | if (!IN_SET(rr->key->type, DNS_TYPE_DS, DNS_TYPE_DNSKEY)) | |
796 | return 0; | |
797 | ||
798 | return set_contains(d->revoked_by_rr, rr); | |
799 | } |