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Commit | Line | Data |
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53e1b683 | 1 | /* SPDX-License-Identifier: LGPL-2.1+ */ |
0d2cd476 LP |
2 | /*** |
3 | This file is part of systemd. | |
4 | ||
5 | Copyright 2015 Lennart Poettering | |
0d2cd476 LP |
6 | ***/ |
7 | ||
62cc1c55 | 8 | #include "sd-messages.h" |
0c857028 | 9 | |
0d2cd476 | 10 | #include "alloc-util.h" |
8e54f5d9 LP |
11 | #include "conf-files.h" |
12 | #include "def.h" | |
13 | #include "dns-domain.h" | |
14 | #include "fd-util.h" | |
15 | #include "fileio.h" | |
16 | #include "hexdecoct.h" | |
17 | #include "parse-util.h" | |
0d2cd476 | 18 | #include "resolved-dns-trust-anchor.h" |
0c857028 | 19 | #include "resolved-dns-dnssec.h" |
8e54f5d9 LP |
20 | #include "set.h" |
21 | #include "string-util.h" | |
22 | #include "strv.h" | |
0d2cd476 | 23 | |
e7d179ac | 24 | static const char trust_anchor_dirs[] = CONF_PATHS_NULSTR("dnssec-trust-anchors.d"); |
8e54f5d9 | 25 | |
3401f0e1 LP |
26 | /* The first DS RR from https://data.iana.org/root-anchors/root-anchors.xml, retrieved December 2015 */ |
27 | static const uint8_t root_digest1[] = | |
0d2cd476 LP |
28 | { 0x49, 0xAA, 0xC1, 0x1D, 0x7B, 0x6F, 0x64, 0x46, 0x70, 0x2E, 0x54, 0xA1, 0x60, 0x73, 0x71, 0x60, |
29 | 0x7A, 0x1A, 0x41, 0x85, 0x52, 0x00, 0xFD, 0x2C, 0xE1, 0xCD, 0xDE, 0x32, 0xF2, 0x4E, 0x8F, 0xB5 }; | |
30 | ||
3401f0e1 LP |
31 | /* The second DS RR from https://data.iana.org/root-anchors/root-anchors.xml, retrieved February 2017 */ |
32 | static const uint8_t root_digest2[] = | |
33 | { 0xE0, 0x6D, 0x44, 0xB8, 0x0B, 0x8F, 0x1D, 0x39, 0xA9, 0x5C, 0x0B, 0x0D, 0x7C, 0x65, 0xD0, 0x84, | |
34 | 0x58, 0xE8, 0x80, 0x40, 0x9B, 0xBC, 0x68, 0x34, 0x57, 0x10, 0x42, 0x37, 0xC7, 0xF8, 0xEC, 0x8D }; | |
35 | ||
86e9cbca LP |
36 | static bool dns_trust_anchor_knows_domain_positive(DnsTrustAnchor *d, const char *name) { |
37 | assert(d); | |
38 | ||
39 | /* Returns true if there's an entry for the specified domain | |
40 | * name in our trust anchor */ | |
41 | ||
42 | return | |
43 | hashmap_contains(d->positive_by_key, &DNS_RESOURCE_KEY_CONST(DNS_CLASS_IN, DNS_TYPE_DNSKEY, name)) || | |
44 | hashmap_contains(d->positive_by_key, &DNS_RESOURCE_KEY_CONST(DNS_CLASS_IN, DNS_TYPE_DS, name)); | |
45 | } | |
46 | ||
3401f0e1 LP |
47 | static int add_root_ksk( |
48 | DnsAnswer *answer, | |
49 | DnsResourceKey *key, | |
50 | uint16_t key_tag, | |
51 | uint8_t algorithm, | |
52 | uint8_t digest_type, | |
53 | const void *digest, | |
54 | size_t digest_size) { | |
55 | ||
0d2cd476 | 56 | _cleanup_(dns_resource_record_unrefp) DnsResourceRecord *rr = NULL; |
3401f0e1 LP |
57 | int r; |
58 | ||
59 | rr = dns_resource_record_new(key); | |
60 | if (!rr) | |
61 | return -ENOMEM; | |
62 | ||
63 | rr->ds.key_tag = key_tag; | |
64 | rr->ds.algorithm = algorithm; | |
65 | rr->ds.digest_type = digest_type; | |
66 | rr->ds.digest_size = digest_size; | |
67 | rr->ds.digest = memdup(digest, rr->ds.digest_size); | |
68 | if (!rr->ds.digest) | |
69 | return -ENOMEM; | |
70 | ||
71 | r = dns_answer_add(answer, rr, 0, DNS_ANSWER_AUTHENTICATED); | |
72 | if (r < 0) | |
73 | return r; | |
74 | ||
75 | return 0; | |
76 | } | |
77 | ||
78 | static int dns_trust_anchor_add_builtin_positive(DnsTrustAnchor *d) { | |
0d2cd476 | 79 | _cleanup_(dns_answer_unrefp) DnsAnswer *answer = NULL; |
3401f0e1 | 80 | _cleanup_(dns_resource_key_unrefp) DnsResourceKey *key = NULL; |
0d2cd476 LP |
81 | int r; |
82 | ||
83 | assert(d); | |
84 | ||
8e54f5d9 | 85 | r = hashmap_ensure_allocated(&d->positive_by_key, &dns_resource_key_hash_ops); |
0d2cd476 LP |
86 | if (r < 0) |
87 | return r; | |
88 | ||
3401f0e1 LP |
89 | /* Only add the built-in trust anchor if there's neither a DS nor a DNSKEY defined for the root domain. That |
90 | * way users have an easy way to override the root domain DS/DNSKEY data. */ | |
86e9cbca | 91 | if (dns_trust_anchor_knows_domain_positive(d, ".")) |
d76f90f1 LP |
92 | return 0; |
93 | ||
3401f0e1 LP |
94 | key = dns_resource_key_new(DNS_CLASS_IN, DNS_TYPE_DS, ""); |
95 | if (!key) | |
0d2cd476 LP |
96 | return -ENOMEM; |
97 | ||
3401f0e1 | 98 | answer = dns_answer_new(2); |
0d2cd476 LP |
99 | if (!answer) |
100 | return -ENOMEM; | |
101 | ||
3401f0e1 LP |
102 | /* Add the two RRs from https://data.iana.org/root-anchors/root-anchors.xml */ |
103 | r = add_root_ksk(answer, key, 19036, DNSSEC_ALGORITHM_RSASHA256, DNSSEC_DIGEST_SHA256, root_digest1, sizeof(root_digest1)); | |
104 | if (r < 0) | |
105 | return r; | |
106 | ||
107 | r = add_root_ksk(answer, key, 20326, DNSSEC_ALGORITHM_RSASHA256, DNSSEC_DIGEST_SHA256, root_digest2, sizeof(root_digest2)); | |
0d2cd476 LP |
108 | if (r < 0) |
109 | return r; | |
110 | ||
3401f0e1 | 111 | r = hashmap_put(d->positive_by_key, key, answer); |
8e54f5d9 LP |
112 | if (r < 0) |
113 | return r; | |
114 | ||
115 | answer = NULL; | |
116 | return 0; | |
117 | } | |
118 | ||
30c77809 LP |
119 | static int dns_trust_anchor_add_builtin_negative(DnsTrustAnchor *d) { |
120 | ||
121 | static const char private_domains[] = | |
122 | /* RFC 6761 says that .test is a special domain for | |
123 | * testing and not to be installed in the root zone */ | |
124 | "test\0" | |
125 | ||
126 | /* RFC 6761 says that these reverse IP lookup ranges | |
127 | * are for private addresses, and hence should not | |
128 | * show up in the root zone */ | |
129 | "10.in-addr.arpa\0" | |
130 | "16.172.in-addr.arpa\0" | |
131 | "17.172.in-addr.arpa\0" | |
132 | "18.172.in-addr.arpa\0" | |
133 | "19.172.in-addr.arpa\0" | |
134 | "20.172.in-addr.arpa\0" | |
135 | "21.172.in-addr.arpa\0" | |
136 | "22.172.in-addr.arpa\0" | |
137 | "23.172.in-addr.arpa\0" | |
138 | "24.172.in-addr.arpa\0" | |
139 | "25.172.in-addr.arpa\0" | |
140 | "26.172.in-addr.arpa\0" | |
141 | "27.172.in-addr.arpa\0" | |
142 | "28.172.in-addr.arpa\0" | |
143 | "29.172.in-addr.arpa\0" | |
144 | "30.172.in-addr.arpa\0" | |
145 | "31.172.in-addr.arpa\0" | |
146 | "168.192.in-addr.arpa\0" | |
147 | ||
f07529fe LP |
148 | /* The same, but for IPv6. */ |
149 | "d.f.ip6.arpa\0" | |
150 | ||
30c77809 LP |
151 | /* RFC 6762 reserves the .local domain for Multicast |
152 | * DNS, it hence cannot appear in the root zone. (Note | |
153 | * that we by default do not route .local traffic to | |
154 | * DNS anyway, except when a configured search domain | |
155 | * suggests so.) */ | |
156 | "local\0" | |
157 | ||
158 | /* These two are well known, popular private zone | |
159 | * TLDs, that are blocked from delegation, according | |
160 | * to: | |
161 | * http://icannwiki.com/Name_Collision#NGPC_Resolution | |
162 | * | |
163 | * There's also ongoing work on making this official | |
164 | * in an RRC: | |
165 | * https://www.ietf.org/archive/id/draft-chapin-additional-reserved-tlds-02.txt */ | |
166 | "home\0" | |
167 | "corp\0" | |
168 | ||
169 | /* The following four TLDs are suggested for private | |
170 | * zones in RFC 6762, Appendix G, and are hence very | |
171 | * unlikely to be made official TLDs any day soon */ | |
172 | "lan\0" | |
173 | "intranet\0" | |
174 | "internal\0" | |
175 | "private\0"; | |
176 | ||
177 | const char *name; | |
178 | int r; | |
179 | ||
180 | assert(d); | |
181 | ||
182 | /* Only add the built-in trust anchor if there's no negative | |
183 | * trust anchor defined at all. This enables easy overriding | |
184 | * of negative trust anchors. */ | |
185 | ||
186 | if (set_size(d->negative_by_name) > 0) | |
187 | return 0; | |
188 | ||
189 | r = set_ensure_allocated(&d->negative_by_name, &dns_name_hash_ops); | |
190 | if (r < 0) | |
191 | return r; | |
192 | ||
193 | /* We add a couple of domains as default negative trust | |
194 | * anchors, where it's very unlikely they will be installed in | |
195 | * the root zone. If they exist they must be private, and thus | |
196 | * unsigned. */ | |
197 | ||
198 | NULSTR_FOREACH(name, private_domains) { | |
199 | ||
200 | if (dns_trust_anchor_knows_domain_positive(d, name)) | |
201 | continue; | |
202 | ||
203 | r = set_put_strdup(d->negative_by_name, name); | |
204 | if (r < 0) | |
205 | return r; | |
206 | } | |
207 | ||
208 | return 0; | |
209 | } | |
210 | ||
8e54f5d9 LP |
211 | static int dns_trust_anchor_load_positive(DnsTrustAnchor *d, const char *path, unsigned line, const char *s) { |
212 | _cleanup_(dns_resource_record_unrefp) DnsResourceRecord *rr = NULL; | |
213 | _cleanup_free_ char *domain = NULL, *class = NULL, *type = NULL; | |
214 | _cleanup_(dns_answer_unrefp) DnsAnswer *answer = NULL; | |
215 | DnsAnswer *old_answer = NULL; | |
216 | const char *p = s; | |
217 | int r; | |
218 | ||
219 | assert(d); | |
220 | assert(line); | |
221 | ||
222 | r = extract_first_word(&p, &domain, NULL, EXTRACT_QUOTES); | |
223 | if (r < 0) | |
224 | return log_warning_errno(r, "Unable to parse domain in line %s:%u: %m", path, line); | |
225 | ||
226 | if (!dns_name_is_valid(domain)) { | |
227 | log_warning("Domain name %s is invalid, at line %s:%u, ignoring line.", domain, path, line); | |
228 | return -EINVAL; | |
229 | } | |
230 | ||
231 | r = extract_many_words(&p, NULL, 0, &class, &type, NULL); | |
232 | if (r < 0) | |
233 | return log_warning_errno(r, "Unable to parse class and type in line %s:%u: %m", path, line); | |
234 | if (r != 2) { | |
235 | log_warning("Missing class or type in line %s:%u", path, line); | |
236 | return -EINVAL; | |
237 | } | |
238 | ||
239 | if (!strcaseeq(class, "IN")) { | |
240 | log_warning("RR class %s is not supported, ignoring line %s:%u.", class, path, line); | |
241 | return -EINVAL; | |
242 | } | |
243 | ||
244 | if (strcaseeq(type, "DS")) { | |
509685f9 | 245 | _cleanup_free_ char *key_tag = NULL, *algorithm = NULL, *digest_type = NULL; |
8e54f5d9 LP |
246 | _cleanup_free_ void *dd = NULL; |
247 | uint16_t kt; | |
248 | int a, dt; | |
249 | size_t l; | |
250 | ||
509685f9 | 251 | r = extract_many_words(&p, NULL, 0, &key_tag, &algorithm, &digest_type, NULL); |
8e54f5d9 LP |
252 | if (r < 0) { |
253 | log_warning_errno(r, "Failed to parse DS parameters on line %s:%u: %m", path, line); | |
254 | return -EINVAL; | |
255 | } | |
509685f9 | 256 | if (r != 3) { |
8e54f5d9 LP |
257 | log_warning("Missing DS parameters on line %s:%u", path, line); |
258 | return -EINVAL; | |
259 | } | |
260 | ||
261 | r = safe_atou16(key_tag, &kt); | |
262 | if (r < 0) | |
263 | return log_warning_errno(r, "Failed to parse DS key tag %s on line %s:%u: %m", key_tag, path, line); | |
264 | ||
265 | a = dnssec_algorithm_from_string(algorithm); | |
266 | if (a < 0) { | |
267 | log_warning("Failed to parse DS algorithm %s on line %s:%u", algorithm, path, line); | |
268 | return -EINVAL; | |
269 | } | |
270 | ||
271 | dt = dnssec_digest_from_string(digest_type); | |
272 | if (dt < 0) { | |
273 | log_warning("Failed to parse DS digest type %s on line %s:%u", digest_type, path, line); | |
274 | return -EINVAL; | |
275 | } | |
276 | ||
509685f9 YW |
277 | if (isempty(p)) { |
278 | log_warning("Missing DS digest on line %s:%u", path, line); | |
279 | return -EINVAL; | |
280 | } | |
281 | ||
282 | r = unhexmem(p, strlen(p), &dd, &l); | |
8e54f5d9 | 283 | if (r < 0) { |
509685f9 | 284 | log_warning("Failed to parse DS digest %s on line %s:%u", p, path, line); |
8e54f5d9 LP |
285 | return -EINVAL; |
286 | } | |
287 | ||
288 | rr = dns_resource_record_new_full(DNS_CLASS_IN, DNS_TYPE_DS, domain); | |
289 | if (!rr) | |
290 | return log_oom(); | |
291 | ||
292 | rr->ds.key_tag = kt; | |
293 | rr->ds.algorithm = a; | |
294 | rr->ds.digest_type = dt; | |
295 | rr->ds.digest_size = l; | |
1cc6c93a | 296 | rr->ds.digest = TAKE_PTR(dd); |
8e54f5d9 LP |
297 | |
298 | } else if (strcaseeq(type, "DNSKEY")) { | |
509685f9 | 299 | _cleanup_free_ char *flags = NULL, *protocol = NULL, *algorithm = NULL; |
8e54f5d9 LP |
300 | _cleanup_free_ void *k = NULL; |
301 | uint16_t f; | |
302 | size_t l; | |
303 | int a; | |
304 | ||
509685f9 | 305 | r = extract_many_words(&p, NULL, 0, &flags, &protocol, &algorithm, NULL); |
8e54f5d9 LP |
306 | if (r < 0) |
307 | return log_warning_errno(r, "Failed to parse DNSKEY parameters on line %s:%u: %m", path, line); | |
509685f9 | 308 | if (r != 3) { |
8e54f5d9 LP |
309 | log_warning("Missing DNSKEY parameters on line %s:%u", path, line); |
310 | return -EINVAL; | |
311 | } | |
312 | ||
313 | if (!streq(protocol, "3")) { | |
314 | log_warning("DNSKEY Protocol is not 3 on line %s:%u", path, line); | |
315 | return -EINVAL; | |
316 | } | |
317 | ||
318 | r = safe_atou16(flags, &f); | |
319 | if (r < 0) | |
320 | return log_warning_errno(r, "Failed to parse DNSKEY flags field %s on line %s:%u", flags, path, line); | |
2a0d751b LP |
321 | if ((f & DNSKEY_FLAG_ZONE_KEY) == 0) { |
322 | log_warning("DNSKEY lacks zone key bit set on line %s:%u", path, line); | |
323 | return -EINVAL; | |
324 | } | |
325 | if ((f & DNSKEY_FLAG_REVOKE)) { | |
326 | log_warning("DNSKEY is already revoked on line %s:%u", path, line); | |
327 | return -EINVAL; | |
328 | } | |
8e54f5d9 LP |
329 | |
330 | a = dnssec_algorithm_from_string(algorithm); | |
331 | if (a < 0) { | |
332 | log_warning("Failed to parse DNSKEY algorithm %s on line %s:%u", algorithm, path, line); | |
333 | return -EINVAL; | |
334 | } | |
335 | ||
509685f9 YW |
336 | if (isempty(p)) { |
337 | log_warning("Missing DNSKEY key on line %s:%u", path, line); | |
338 | return -EINVAL; | |
339 | } | |
340 | ||
341 | r = unbase64mem(p, strlen(p), &k, &l); | |
8e54f5d9 | 342 | if (r < 0) |
509685f9 | 343 | return log_warning_errno(r, "Failed to parse DNSKEY key data %s on line %s:%u", p, path, line); |
8e54f5d9 LP |
344 | |
345 | rr = dns_resource_record_new_full(DNS_CLASS_IN, DNS_TYPE_DNSKEY, domain); | |
346 | if (!rr) | |
347 | return log_oom(); | |
348 | ||
349 | rr->dnskey.flags = f; | |
350 | rr->dnskey.protocol = 3; | |
351 | rr->dnskey.algorithm = a; | |
352 | rr->dnskey.key_size = l; | |
1cc6c93a | 353 | rr->dnskey.key = TAKE_PTR(k); |
8e54f5d9 LP |
354 | |
355 | } else { | |
356 | log_warning("RR type %s is not supported, ignoring line %s:%u.", type, path, line); | |
357 | return -EINVAL; | |
358 | } | |
359 | ||
8e54f5d9 | 360 | r = hashmap_ensure_allocated(&d->positive_by_key, &dns_resource_key_hash_ops); |
0d2cd476 | 361 | if (r < 0) |
b3331c39 | 362 | return log_oom(); |
0d2cd476 | 363 | |
8e54f5d9 LP |
364 | old_answer = hashmap_get(d->positive_by_key, rr->key); |
365 | answer = dns_answer_ref(old_answer); | |
366 | ||
367 | r = dns_answer_add_extend(&answer, rr, 0, DNS_ANSWER_AUTHENTICATED); | |
368 | if (r < 0) | |
369 | return log_error_errno(r, "Failed to add trust anchor RR: %m"); | |
370 | ||
371 | r = hashmap_replace(d->positive_by_key, rr->key, answer); | |
372 | if (r < 0) | |
373 | return log_error_errno(r, "Failed to add answer to trust anchor: %m"); | |
374 | ||
375 | old_answer = dns_answer_unref(old_answer); | |
0d2cd476 | 376 | answer = NULL; |
8e54f5d9 LP |
377 | |
378 | return 0; | |
379 | } | |
380 | ||
381 | static int dns_trust_anchor_load_negative(DnsTrustAnchor *d, const char *path, unsigned line, const char *s) { | |
382 | _cleanup_free_ char *domain = NULL; | |
383 | const char *p = s; | |
384 | int r; | |
385 | ||
386 | assert(d); | |
387 | assert(line); | |
388 | ||
389 | r = extract_first_word(&p, &domain, NULL, EXTRACT_QUOTES); | |
390 | if (r < 0) | |
391 | return log_warning_errno(r, "Unable to parse line %s:%u: %m", path, line); | |
392 | ||
393 | if (!dns_name_is_valid(domain)) { | |
394 | log_warning("Domain name %s is invalid, at line %s:%u, ignoring line.", domain, path, line); | |
395 | return -EINVAL; | |
396 | } | |
397 | ||
398 | if (!isempty(p)) { | |
399 | log_warning("Trailing garbage at line %s:%u, ignoring line.", path, line); | |
400 | return -EINVAL; | |
401 | } | |
402 | ||
403 | r = set_ensure_allocated(&d->negative_by_name, &dns_name_hash_ops); | |
404 | if (r < 0) | |
b3331c39 | 405 | return log_oom(); |
8e54f5d9 LP |
406 | |
407 | r = set_put(d->negative_by_name, domain); | |
408 | if (r < 0) | |
409 | return log_oom(); | |
410 | if (r > 0) | |
411 | domain = NULL; | |
412 | ||
413 | return 0; | |
414 | } | |
415 | ||
416 | static int dns_trust_anchor_load_files( | |
417 | DnsTrustAnchor *d, | |
418 | const char *suffix, | |
419 | int (*loader)(DnsTrustAnchor *d, const char *path, unsigned n, const char *line)) { | |
420 | ||
421 | _cleanup_strv_free_ char **files = NULL; | |
422 | char **f; | |
423 | int r; | |
424 | ||
425 | assert(d); | |
426 | assert(suffix); | |
427 | assert(loader); | |
428 | ||
b5084605 | 429 | r = conf_files_list_nulstr(&files, suffix, NULL, 0, trust_anchor_dirs); |
8e54f5d9 LP |
430 | if (r < 0) |
431 | return log_error_errno(r, "Failed to enumerate %s trust anchor files: %m", suffix); | |
432 | ||
433 | STRV_FOREACH(f, files) { | |
434 | _cleanup_fclose_ FILE *g = NULL; | |
435 | char line[LINE_MAX]; | |
436 | unsigned n = 0; | |
437 | ||
438 | g = fopen(*f, "r"); | |
439 | if (!g) { | |
440 | if (errno == ENOENT) | |
441 | continue; | |
442 | ||
443 | log_warning_errno(errno, "Failed to open %s: %m", *f); | |
444 | continue; | |
445 | } | |
446 | ||
447 | FOREACH_LINE(line, g, log_warning_errno(errno, "Failed to read %s, ignoring: %m", *f)) { | |
448 | char *l; | |
449 | ||
450 | n++; | |
451 | ||
452 | l = strstrip(line); | |
453 | if (isempty(l)) | |
454 | continue; | |
455 | ||
456 | if (*l == ';') | |
457 | continue; | |
458 | ||
459 | (void) loader(d, *f, n, l); | |
460 | } | |
461 | } | |
462 | ||
463 | return 0; | |
464 | } | |
465 | ||
bec69050 LP |
466 | static int domain_name_cmp(const void *a, const void *b) { |
467 | char **x = (char**) a, **y = (char**) b; | |
468 | ||
469 | return dns_name_compare_func(*x, *y); | |
470 | } | |
471 | ||
472 | static int dns_trust_anchor_dump(DnsTrustAnchor *d) { | |
8e54f5d9 LP |
473 | DnsAnswer *a; |
474 | Iterator i; | |
475 | ||
476 | assert(d); | |
477 | ||
105f6c4b LP |
478 | if (hashmap_isempty(d->positive_by_key)) |
479 | log_info("No positive trust anchors defined."); | |
480 | else { | |
481 | log_info("Positive Trust Anchors:"); | |
482 | HASHMAP_FOREACH(a, d->positive_by_key, i) { | |
483 | DnsResourceRecord *rr; | |
484 | ||
485 | DNS_ANSWER_FOREACH(rr, a) | |
486 | log_info("%s", dns_resource_record_to_string(rr)); | |
487 | } | |
8e54f5d9 LP |
488 | } |
489 | ||
105f6c4b LP |
490 | if (set_isempty(d->negative_by_name)) |
491 | log_info("No negative trust anchors defined."); | |
492 | else { | |
bec69050 LP |
493 | _cleanup_free_ char **l = NULL, *j = NULL; |
494 | ||
495 | l = set_get_strv(d->negative_by_name); | |
496 | if (!l) | |
497 | return log_oom(); | |
8e54f5d9 | 498 | |
bec69050 LP |
499 | qsort_safe(l, set_size(d->negative_by_name), sizeof(char*), domain_name_cmp); |
500 | ||
501 | j = strv_join(l, " "); | |
502 | if (!j) | |
503 | return log_oom(); | |
504 | ||
505 | log_info("Negative trust anchors: %s", j); | |
8e54f5d9 | 506 | } |
bec69050 LP |
507 | |
508 | return 0; | |
8e54f5d9 LP |
509 | } |
510 | ||
511 | int dns_trust_anchor_load(DnsTrustAnchor *d) { | |
512 | int r; | |
513 | ||
514 | assert(d); | |
515 | ||
516 | /* If loading things from disk fails, we don't consider this fatal */ | |
517 | (void) dns_trust_anchor_load_files(d, ".positive", dns_trust_anchor_load_positive); | |
518 | (void) dns_trust_anchor_load_files(d, ".negative", dns_trust_anchor_load_negative); | |
519 | ||
520 | /* However, if the built-in DS fails, then we have a problem. */ | |
30c77809 LP |
521 | r = dns_trust_anchor_add_builtin_positive(d); |
522 | if (r < 0) | |
523 | return log_error_errno(r, "Failed to add built-in positive trust anchor: %m"); | |
524 | ||
525 | r = dns_trust_anchor_add_builtin_negative(d); | |
8e54f5d9 | 526 | if (r < 0) |
30c77809 | 527 | return log_error_errno(r, "Failed to add built-in negative trust anchor: %m"); |
8e54f5d9 LP |
528 | |
529 | dns_trust_anchor_dump(d); | |
530 | ||
0d2cd476 LP |
531 | return 0; |
532 | } | |
533 | ||
534 | void dns_trust_anchor_flush(DnsTrustAnchor *d) { | |
0d2cd476 LP |
535 | assert(d); |
536 | ||
224b0e7a ZJS |
537 | d->positive_by_key = hashmap_free_with_destructor(d->positive_by_key, dns_answer_unref); |
538 | d->revoked_by_rr = set_free_with_destructor(d->revoked_by_rr, dns_resource_record_unref); | |
8e54f5d9 | 539 | d->negative_by_name = set_free_free(d->negative_by_name); |
0d2cd476 LP |
540 | } |
541 | ||
8e54f5d9 | 542 | int dns_trust_anchor_lookup_positive(DnsTrustAnchor *d, const DnsResourceKey *key, DnsAnswer **ret) { |
0d2cd476 LP |
543 | DnsAnswer *a; |
544 | ||
545 | assert(d); | |
546 | assert(key); | |
547 | assert(ret); | |
548 | ||
549 | /* We only serve DS and DNSKEY RRs. */ | |
550 | if (!IN_SET(key->type, DNS_TYPE_DS, DNS_TYPE_DNSKEY)) | |
551 | return 0; | |
552 | ||
8e54f5d9 | 553 | a = hashmap_get(d->positive_by_key, key); |
0d2cd476 LP |
554 | if (!a) |
555 | return 0; | |
556 | ||
557 | *ret = dns_answer_ref(a); | |
558 | return 1; | |
559 | } | |
8e54f5d9 LP |
560 | |
561 | int dns_trust_anchor_lookup_negative(DnsTrustAnchor *d, const char *name) { | |
c775838a LP |
562 | int r; |
563 | ||
8e54f5d9 LP |
564 | assert(d); |
565 | assert(name); | |
566 | ||
c775838a LP |
567 | for (;;) { |
568 | /* If the domain is listed as-is in the NTA database, then that counts */ | |
569 | if (set_contains(d->negative_by_name, name)) | |
570 | return true; | |
571 | ||
572 | /* If the domain isn't listed as NTA, but is listed as positive trust anchor, then that counts. See RFC | |
573 | * 7646, section 1.1 */ | |
574 | if (hashmap_contains(d->positive_by_key, &DNS_RESOURCE_KEY_CONST(DNS_CLASS_IN, DNS_TYPE_DS, name))) | |
575 | return false; | |
576 | ||
577 | if (hashmap_contains(d->positive_by_key, &DNS_RESOURCE_KEY_CONST(DNS_CLASS_IN, DNS_TYPE_KEY, name))) | |
578 | return false; | |
579 | ||
580 | /* And now, let's look at the parent, and check that too */ | |
581 | r = dns_name_parent(&name); | |
582 | if (r < 0) | |
583 | return r; | |
584 | if (r == 0) | |
585 | break; | |
586 | } | |
587 | ||
588 | return false; | |
8e54f5d9 | 589 | } |
0c857028 | 590 | |
c9c72065 LP |
591 | static int dns_trust_anchor_revoked_put(DnsTrustAnchor *d, DnsResourceRecord *rr) { |
592 | int r; | |
593 | ||
594 | assert(d); | |
595 | ||
596 | r = set_ensure_allocated(&d->revoked_by_rr, &dns_resource_record_hash_ops); | |
597 | if (r < 0) | |
598 | return r; | |
599 | ||
600 | r = set_put(d->revoked_by_rr, rr); | |
601 | if (r < 0) | |
602 | return r; | |
603 | if (r > 0) | |
604 | dns_resource_record_ref(rr); | |
605 | ||
606 | return r; | |
607 | } | |
608 | ||
0c857028 LP |
609 | static int dns_trust_anchor_remove_revoked(DnsTrustAnchor *d, DnsResourceRecord *rr) { |
610 | _cleanup_(dns_answer_unrefp) DnsAnswer *new_answer = NULL; | |
611 | DnsAnswer *old_answer; | |
612 | int r; | |
613 | ||
c9c72065 LP |
614 | /* Remember that this is a revoked trust anchor RR */ |
615 | r = dns_trust_anchor_revoked_put(d, rr); | |
616 | if (r < 0) | |
617 | return r; | |
618 | ||
619 | /* Remove this from the positive trust anchor */ | |
0c857028 LP |
620 | old_answer = hashmap_get(d->positive_by_key, rr->key); |
621 | if (!old_answer) | |
622 | return 0; | |
623 | ||
624 | new_answer = dns_answer_ref(old_answer); | |
625 | ||
626 | r = dns_answer_remove_by_rr(&new_answer, rr); | |
627 | if (r <= 0) | |
628 | return r; | |
629 | ||
630 | /* We found the key! Warn the user */ | |
631 | log_struct(LOG_WARNING, | |
2b044526 | 632 | "MESSAGE_ID=" SD_MESSAGE_DNSSEC_TRUST_ANCHOR_REVOKED_STR, |
0c857028 LP |
633 | 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)), |
634 | "TRUST_ANCHOR=%s", dns_resource_record_to_string(rr), | |
635 | NULL); | |
636 | ||
637 | if (dns_answer_size(new_answer) <= 0) { | |
638 | assert_se(hashmap_remove(d->positive_by_key, rr->key) == old_answer); | |
639 | dns_answer_unref(old_answer); | |
640 | return 1; | |
641 | } | |
642 | ||
643 | r = hashmap_replace(d->positive_by_key, new_answer->items[0].rr->key, new_answer); | |
644 | if (r < 0) | |
645 | return r; | |
646 | ||
647 | new_answer = NULL; | |
648 | dns_answer_unref(old_answer); | |
649 | return 1; | |
650 | } | |
651 | ||
652 | static int dns_trust_anchor_check_revoked_one(DnsTrustAnchor *d, DnsResourceRecord *revoked_dnskey) { | |
653 | DnsAnswer *a; | |
654 | int r; | |
655 | ||
656 | assert(d); | |
657 | assert(revoked_dnskey); | |
658 | assert(revoked_dnskey->key->type == DNS_TYPE_DNSKEY); | |
659 | assert(revoked_dnskey->dnskey.flags & DNSKEY_FLAG_REVOKE); | |
660 | ||
661 | a = hashmap_get(d->positive_by_key, revoked_dnskey->key); | |
662 | if (a) { | |
663 | DnsResourceRecord *anchor; | |
664 | ||
665 | /* First, look for the precise DNSKEY in our trust anchor database */ | |
666 | ||
667 | DNS_ANSWER_FOREACH(anchor, a) { | |
668 | ||
669 | if (anchor->dnskey.protocol != revoked_dnskey->dnskey.protocol) | |
670 | continue; | |
671 | ||
672 | if (anchor->dnskey.algorithm != revoked_dnskey->dnskey.algorithm) | |
673 | continue; | |
674 | ||
675 | if (anchor->dnskey.key_size != revoked_dnskey->dnskey.key_size) | |
676 | continue; | |
677 | ||
c9c72065 LP |
678 | /* Note that we allow the REVOKE bit to be |
679 | * different! It will be set in the revoked | |
680 | * key, but unset in our version of it */ | |
0c857028 LP |
681 | if (((anchor->dnskey.flags ^ revoked_dnskey->dnskey.flags) | DNSKEY_FLAG_REVOKE) != DNSKEY_FLAG_REVOKE) |
682 | continue; | |
683 | ||
684 | if (memcmp(anchor->dnskey.key, revoked_dnskey->dnskey.key, anchor->dnskey.key_size) != 0) | |
685 | continue; | |
686 | ||
687 | dns_trust_anchor_remove_revoked(d, anchor); | |
688 | break; | |
689 | } | |
690 | } | |
691 | ||
1c02e7ba | 692 | 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 |
693 | if (a) { |
694 | DnsResourceRecord *anchor; | |
695 | ||
696 | /* Second, look for DS RRs matching this DNSKEY in our trust anchor database */ | |
697 | ||
698 | DNS_ANSWER_FOREACH(anchor, a) { | |
699 | ||
c9c72065 LP |
700 | /* We set mask_revoke to true here, since our |
701 | * DS fingerprint will be the one of the | |
702 | * unrevoked DNSKEY, but the one we got passed | |
703 | * here has the bit set. */ | |
96bb7673 | 704 | r = dnssec_verify_dnskey_by_ds(revoked_dnskey, anchor, true); |
0c857028 LP |
705 | if (r < 0) |
706 | return r; | |
707 | if (r == 0) | |
708 | continue; | |
709 | ||
710 | dns_trust_anchor_remove_revoked(d, anchor); | |
711 | break; | |
712 | } | |
713 | } | |
714 | ||
715 | return 0; | |
716 | } | |
717 | ||
d424da2a LP |
718 | int dns_trust_anchor_check_revoked(DnsTrustAnchor *d, DnsResourceRecord *dnskey, DnsAnswer *rrs) { |
719 | DnsResourceRecord *rrsig; | |
0c857028 LP |
720 | int r; |
721 | ||
722 | assert(d); | |
d424da2a LP |
723 | assert(dnskey); |
724 | ||
725 | /* Looks if "dnskey" is a self-signed RR that has been revoked | |
726 | * and matches one of our trust anchor entries. If so, removes | |
727 | * it from the trust anchor and returns > 0. */ | |
0c857028 | 728 | |
d424da2a LP |
729 | if (dnskey->key->type != DNS_TYPE_DNSKEY) |
730 | return 0; | |
0c857028 | 731 | |
d424da2a LP |
732 | /* Is this DNSKEY revoked? */ |
733 | if ((dnskey->dnskey.flags & DNSKEY_FLAG_REVOKE) == 0) | |
0c857028 LP |
734 | return 0; |
735 | ||
d424da2a LP |
736 | /* Could this be interesting to us at all? If not, |
737 | * there's no point in looking for and verifying a | |
738 | * self-signed RRSIG. */ | |
1c02e7ba | 739 | if (!dns_trust_anchor_knows_domain_positive(d, dns_resource_key_name(dnskey->key))) |
d424da2a LP |
740 | return 0; |
741 | ||
742 | /* Look for a self-signed RRSIG in the other rrs belonging to this DNSKEY */ | |
743 | DNS_ANSWER_FOREACH(rrsig, rrs) { | |
0c857028 LP |
744 | DnssecResult result; |
745 | ||
d424da2a LP |
746 | if (rrsig->key->type != DNS_TYPE_RRSIG) |
747 | continue; | |
748 | ||
749 | r = dnssec_rrsig_match_dnskey(rrsig, dnskey, true); | |
0c857028 LP |
750 | if (r < 0) |
751 | return r; | |
752 | if (r == 0) | |
753 | continue; | |
754 | ||
d424da2a LP |
755 | r = dnssec_verify_rrset(rrs, dnskey->key, rrsig, dnskey, USEC_INFINITY, &result); |
756 | if (r < 0) | |
757 | return r; | |
758 | if (result != DNSSEC_VALIDATED) | |
0c857028 LP |
759 | continue; |
760 | ||
d424da2a LP |
761 | /* Bingo! This is a revoked self-signed DNSKEY. Let's |
762 | * see if this precise one exists in our trust anchor | |
763 | * database, too. */ | |
764 | r = dns_trust_anchor_check_revoked_one(d, dnskey); | |
765 | if (r < 0) | |
766 | return r; | |
0c857028 | 767 | |
d424da2a | 768 | return 1; |
0c857028 LP |
769 | } |
770 | ||
771 | return 0; | |
772 | } | |
c9c72065 LP |
773 | |
774 | int dns_trust_anchor_is_revoked(DnsTrustAnchor *d, DnsResourceRecord *rr) { | |
775 | assert(d); | |
776 | ||
777 | if (!IN_SET(rr->key->type, DNS_TYPE_DS, DNS_TYPE_DNSKEY)) | |
778 | return 0; | |
779 | ||
780 | return set_contains(d->revoked_by_rr, rr); | |
781 | } |