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Commit | Line | Data |
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53e1b683 | 1 | /* SPDX-License-Identifier: LGPL-2.1+ */ |
74b2466e LP |
2 | /*** |
3 | This file is part of systemd. | |
4 | ||
5 | Copyright 2014 Lennart Poettering | |
6 | ||
7 | systemd is free software; you can redistribute it and/or modify it | |
8 | under the terms of the GNU Lesser General Public License as published by | |
9 | the Free Software Foundation; either version 2.1 of the License, or | |
10 | (at your option) any later version. | |
11 | ||
12 | systemd is distributed in the hope that it will be useful, but | |
13 | WITHOUT ANY WARRANTY; without even the implied warranty of | |
14 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
15 | Lesser General Public License for more details. | |
16 | ||
17 | You should have received a copy of the GNU Lesser General Public License | |
18 | along with systemd; If not, see <http://www.gnu.org/licenses/>. | |
19 | ***/ | |
20 | ||
349cc4a5 | 21 | #if HAVE_LIBIDN2 |
87057e24 | 22 | # include <idn2.h> |
349cc4a5 | 23 | #elif HAVE_LIBIDN |
87057e24 ZJS |
24 | # include <idna.h> |
25 | # include <stringprep.h> | |
bdf10b5b LP |
26 | #endif |
27 | ||
a8fbdf54 TA |
28 | #include <endian.h> |
29 | #include <netinet/in.h> | |
30 | #include <stdio.h> | |
31 | #include <string.h> | |
32 | #include <sys/socket.h> | |
33 | ||
b5efdb8a | 34 | #include "alloc-util.h" |
4ad7f276 | 35 | #include "dns-domain.h" |
a8fbdf54 | 36 | #include "hashmap.h" |
e4e73a63 | 37 | #include "hexdecoct.h" |
a8fbdf54 TA |
38 | #include "in-addr-util.h" |
39 | #include "macro.h" | |
6bedfcbb LP |
40 | #include "parse-util.h" |
41 | #include "string-util.h" | |
dc477e73 | 42 | #include "strv.h" |
0a49b6b6 | 43 | #include "utf8.h" |
74b2466e LP |
44 | |
45 | int dns_label_unescape(const char **name, char *dest, size_t sz) { | |
46 | const char *n; | |
47 | char *d; | |
48 | int r = 0; | |
49 | ||
50 | assert(name); | |
51 | assert(*name); | |
74b2466e LP |
52 | |
53 | n = *name; | |
54 | d = dest; | |
55 | ||
56 | for (;;) { | |
57 | if (*n == '.') { | |
58 | n++; | |
59 | break; | |
60 | } | |
61 | ||
62 | if (*n == 0) | |
63 | break; | |
64 | ||
1fa65c59 LP |
65 | if (r >= DNS_LABEL_MAX) |
66 | return -EINVAL; | |
67 | ||
37ade128 LP |
68 | if (sz <= 0) |
69 | return -ENOBUFS; | |
70 | ||
74b2466e LP |
71 | if (*n == '\\') { |
72 | /* Escaped character */ | |
73 | ||
74 | n++; | |
75 | ||
76 | if (*n == 0) | |
77 | /* Ending NUL */ | |
78 | return -EINVAL; | |
79 | ||
4c701096 | 80 | else if (IN_SET(*n, '\\', '.')) { |
74b2466e | 81 | /* Escaped backslash or dot */ |
f7455baa LP |
82 | |
83 | if (d) | |
84 | *(d++) = *n; | |
74b2466e LP |
85 | sz--; |
86 | r++; | |
f7455baa | 87 | n++; |
74b2466e LP |
88 | |
89 | } else if (n[0] >= '0' && n[0] <= '9') { | |
90 | unsigned k; | |
91 | ||
92 | /* Escaped literal ASCII character */ | |
93 | ||
94 | if (!(n[1] >= '0' && n[1] <= '9') || | |
95 | !(n[2] >= '0' && n[2] <= '9')) | |
96 | return -EINVAL; | |
97 | ||
98 | k = ((unsigned) (n[0] - '0') * 100) + | |
99 | ((unsigned) (n[1] - '0') * 10) + | |
100 | ((unsigned) (n[2] - '0')); | |
101 | ||
c7feab76 LP |
102 | /* Don't allow anything that doesn't |
103 | * fit in 8bit. Note that we do allow | |
104 | * control characters, as some servers | |
105 | * (e.g. cloudflare) are happy to | |
106 | * generate labels with them | |
107 | * inside. */ | |
108 | if (k > 255) | |
74b2466e LP |
109 | return -EINVAL; |
110 | ||
f7455baa LP |
111 | if (d) |
112 | *(d++) = (char) k; | |
74b2466e LP |
113 | sz--; |
114 | r++; | |
115 | ||
116 | n += 3; | |
117 | } else | |
118 | return -EINVAL; | |
119 | ||
07bed172 | 120 | } else if ((uint8_t) *n >= (uint8_t) ' ' && *n != 127) { |
74b2466e LP |
121 | |
122 | /* Normal character */ | |
f7455baa LP |
123 | |
124 | if (d) | |
125 | *(d++) = *n; | |
74b2466e LP |
126 | sz--; |
127 | r++; | |
f7455baa | 128 | n++; |
74b2466e LP |
129 | } else |
130 | return -EINVAL; | |
131 | } | |
132 | ||
133 | /* Empty label that is not at the end? */ | |
134 | if (r == 0 && *n) | |
135 | return -EINVAL; | |
136 | ||
f35c467d MP |
137 | /* More than one trailing dot? */ |
138 | if (*n == '.') | |
139 | return -EINVAL; | |
140 | ||
f7455baa | 141 | if (sz >= 1 && d) |
74b2466e LP |
142 | *d = 0; |
143 | ||
144 | *name = n; | |
145 | return r; | |
146 | } | |
147 | ||
642900d3 TG |
148 | /* @label_terminal: terminal character of a label, updated to point to the terminal character of |
149 | * the previous label (always skipping one dot) or to NULL if there are no more | |
150 | * labels. */ | |
151 | int dns_label_unescape_suffix(const char *name, const char **label_terminal, char *dest, size_t sz) { | |
152 | const char *terminal; | |
153 | int r; | |
154 | ||
155 | assert(name); | |
156 | assert(label_terminal); | |
157 | assert(dest); | |
158 | ||
159 | /* no more labels */ | |
160 | if (!*label_terminal) { | |
161 | if (sz >= 1) | |
162 | *dest = 0; | |
163 | ||
164 | return 0; | |
165 | } | |
166 | ||
56512859 | 167 | terminal = *label_terminal; |
4c701096 | 168 | assert(IN_SET(*terminal, 0, '.')); |
642900d3 | 169 | |
56512859 LP |
170 | /* Skip current terminal character (and accept domain names ending it ".") */ |
171 | if (*terminal == 0) | |
172 | terminal--; | |
173 | if (terminal >= name && *terminal == '.') | |
174 | terminal--; | |
642900d3 | 175 | |
56512859 | 176 | /* Point name to the last label, and terminal to the preceding terminal symbol (or make it a NULL pointer) */ |
642900d3 TG |
177 | for (;;) { |
178 | if (terminal < name) { | |
56512859 | 179 | /* Reached the first label, so indicate that there are no more */ |
642900d3 TG |
180 | terminal = NULL; |
181 | break; | |
182 | } | |
183 | ||
56512859 | 184 | /* Find the start of the last label */ |
642900d3 TG |
185 | if (*terminal == '.') { |
186 | const char *y; | |
187 | unsigned slashes = 0; | |
188 | ||
189 | for (y = terminal - 1; y >= name && *y == '\\'; y--) | |
313cefa1 | 190 | slashes++; |
642900d3 TG |
191 | |
192 | if (slashes % 2 == 0) { | |
56512859 | 193 | /* The '.' was not escaped */ |
642900d3 TG |
194 | name = terminal + 1; |
195 | break; | |
196 | } else { | |
197 | terminal = y; | |
198 | continue; | |
199 | } | |
200 | } | |
201 | ||
313cefa1 | 202 | terminal--; |
642900d3 TG |
203 | } |
204 | ||
205 | r = dns_label_unescape(&name, dest, sz); | |
206 | if (r < 0) | |
207 | return r; | |
208 | ||
209 | *label_terminal = terminal; | |
210 | ||
211 | return r; | |
212 | } | |
213 | ||
422baca0 | 214 | int dns_label_escape(const char *p, size_t l, char *dest, size_t sz) { |
74b2466e | 215 | char *q; |
74b2466e | 216 | |
3b37fa73 LP |
217 | /* DNS labels must be between 1 and 63 characters long. A |
218 | * zero-length label does not exist. See RFC 2182, Section | |
219 | * 11. */ | |
220 | ||
221 | if (l <= 0 || l > DNS_LABEL_MAX) | |
1fa65c59 | 222 | return -EINVAL; |
422baca0 | 223 | if (sz < 1) |
37ade128 | 224 | return -ENOBUFS; |
1fa65c59 | 225 | |
422baca0 LP |
226 | assert(p); |
227 | assert(dest); | |
74b2466e | 228 | |
422baca0 | 229 | q = dest; |
74b2466e LP |
230 | while (l > 0) { |
231 | ||
4c701096 | 232 | if (IN_SET(*p, '.', '\\')) { |
74b2466e | 233 | |
3b37fa73 LP |
234 | /* Dot or backslash */ |
235 | ||
422baca0 | 236 | if (sz < 3) |
37ade128 | 237 | return -ENOBUFS; |
422baca0 | 238 | |
74b2466e LP |
239 | *(q++) = '\\'; |
240 | *(q++) = *p; | |
241 | ||
422baca0 LP |
242 | sz -= 2; |
243 | ||
4c701096 | 244 | } else if (IN_SET(*p, '_', '-') || |
74b2466e LP |
245 | (*p >= '0' && *p <= '9') || |
246 | (*p >= 'a' && *p <= 'z') || | |
247 | (*p >= 'A' && *p <= 'Z')) { | |
248 | ||
249 | /* Proper character */ | |
422baca0 LP |
250 | |
251 | if (sz < 2) | |
37ade128 | 252 | return -ENOBUFS; |
422baca0 | 253 | |
74b2466e | 254 | *(q++) = *p; |
422baca0 LP |
255 | sz -= 1; |
256 | ||
c7feab76 | 257 | } else { |
74b2466e LP |
258 | |
259 | /* Everything else */ | |
422baca0 LP |
260 | |
261 | if (sz < 5) | |
37ade128 | 262 | return -ENOBUFS; |
422baca0 | 263 | |
74b2466e | 264 | *(q++) = '\\'; |
07bed172 LP |
265 | *(q++) = '0' + (char) ((uint8_t) *p / 100); |
266 | *(q++) = '0' + (char) (((uint8_t) *p / 10) % 10); | |
267 | *(q++) = '0' + (char) ((uint8_t) *p % 10); | |
74b2466e | 268 | |
422baca0 | 269 | sz -= 4; |
c7feab76 | 270 | } |
74b2466e LP |
271 | |
272 | p++; | |
273 | l--; | |
274 | } | |
275 | ||
276 | *q = 0; | |
422baca0 LP |
277 | return (int) (q - dest); |
278 | } | |
279 | ||
280 | int dns_label_escape_new(const char *p, size_t l, char **ret) { | |
281 | _cleanup_free_ char *s = NULL; | |
282 | int r; | |
283 | ||
284 | assert(p); | |
285 | assert(ret); | |
286 | ||
3b37fa73 | 287 | if (l <= 0 || l > DNS_LABEL_MAX) |
422baca0 LP |
288 | return -EINVAL; |
289 | ||
290 | s = new(char, DNS_LABEL_ESCAPED_MAX); | |
291 | if (!s) | |
292 | return -ENOMEM; | |
293 | ||
294 | r = dns_label_escape(p, l, s, DNS_LABEL_ESCAPED_MAX); | |
295 | if (r < 0) | |
296 | return r; | |
297 | ||
ae2a15bc | 298 | *ret = TAKE_PTR(s); |
74b2466e LP |
299 | |
300 | return r; | |
301 | } | |
302 | ||
349cc4a5 | 303 | #if HAVE_LIBIDN |
87057e24 | 304 | int dns_label_apply_idna(const char *encoded, size_t encoded_size, char *decoded, size_t decoded_max) { |
bdf10b5b | 305 | _cleanup_free_ uint32_t *input = NULL; |
3b37fa73 | 306 | size_t input_size, l; |
bdf10b5b LP |
307 | const char *p; |
308 | bool contains_8bit = false; | |
3b37fa73 | 309 | char buffer[DNS_LABEL_MAX+1]; |
bdf10b5b LP |
310 | |
311 | assert(encoded); | |
312 | assert(decoded); | |
3b37fa73 LP |
313 | |
314 | /* Converts an U-label into an A-label */ | |
bdf10b5b LP |
315 | |
316 | if (encoded_size <= 0) | |
3b37fa73 | 317 | return -EINVAL; |
bdf10b5b LP |
318 | |
319 | for (p = encoded; p < encoded + encoded_size; p++) | |
320 | if ((uint8_t) *p > 127) | |
321 | contains_8bit = true; | |
322 | ||
3b37fa73 LP |
323 | if (!contains_8bit) { |
324 | if (encoded_size > DNS_LABEL_MAX) | |
325 | return -EINVAL; | |
326 | ||
bdf10b5b | 327 | return 0; |
3b37fa73 | 328 | } |
bdf10b5b LP |
329 | |
330 | input = stringprep_utf8_to_ucs4(encoded, encoded_size, &input_size); | |
331 | if (!input) | |
332 | return -ENOMEM; | |
333 | ||
3b37fa73 LP |
334 | if (idna_to_ascii_4i(input, input_size, buffer, 0) != 0) |
335 | return -EINVAL; | |
336 | ||
337 | l = strlen(buffer); | |
338 | ||
c629ff58 | 339 | /* Verify that the result is not longer than one DNS label. */ |
3b37fa73 | 340 | if (l <= 0 || l > DNS_LABEL_MAX) |
bdf10b5b | 341 | return -EINVAL; |
3b37fa73 | 342 | if (l > decoded_max) |
37ade128 | 343 | return -ENOBUFS; |
3b37fa73 LP |
344 | |
345 | memcpy(decoded, buffer, l); | |
bdf10b5b | 346 | |
3b37fa73 LP |
347 | /* If there's room, append a trailing NUL byte, but only then */ |
348 | if (decoded_max > l) | |
349 | decoded[l] = 0; | |
350 | ||
351 | return (int) l; | |
bdf10b5b LP |
352 | } |
353 | ||
354 | int dns_label_undo_idna(const char *encoded, size_t encoded_size, char *decoded, size_t decoded_max) { | |
bdf10b5b LP |
355 | size_t input_size, output_size; |
356 | _cleanup_free_ uint32_t *input = NULL; | |
357 | _cleanup_free_ char *result = NULL; | |
358 | uint32_t *output = NULL; | |
359 | size_t w; | |
360 | ||
3b37fa73 | 361 | /* To be invoked after unescaping. Converts an A-label into an U-label. */ |
bdf10b5b LP |
362 | |
363 | assert(encoded); | |
364 | assert(decoded); | |
365 | ||
3b37fa73 LP |
366 | if (encoded_size <= 0 || encoded_size > DNS_LABEL_MAX) |
367 | return -EINVAL; | |
368 | ||
bdf10b5b LP |
369 | if (encoded_size < sizeof(IDNA_ACE_PREFIX)-1) |
370 | return 0; | |
371 | ||
372 | if (memcmp(encoded, IDNA_ACE_PREFIX, sizeof(IDNA_ACE_PREFIX) -1) != 0) | |
373 | return 0; | |
374 | ||
375 | input = stringprep_utf8_to_ucs4(encoded, encoded_size, &input_size); | |
376 | if (!input) | |
377 | return -ENOMEM; | |
378 | ||
379 | output_size = input_size; | |
380 | output = newa(uint32_t, output_size); | |
381 | ||
382 | idna_to_unicode_44i(input, input_size, output, &output_size, 0); | |
383 | ||
384 | result = stringprep_ucs4_to_utf8(output, output_size, NULL, &w); | |
385 | if (!result) | |
386 | return -ENOMEM; | |
387 | if (w <= 0) | |
bdf10b5b | 388 | return -EINVAL; |
3b37fa73 | 389 | if (w > decoded_max) |
37ade128 | 390 | return -ENOBUFS; |
3b37fa73 LP |
391 | |
392 | memcpy(decoded, result, w); | |
393 | ||
394 | /* Append trailing NUL byte if there's space, but only then. */ | |
395 | if (decoded_max > w) | |
396 | decoded[w] = 0; | |
bdf10b5b | 397 | |
bdf10b5b | 398 | return w; |
bdf10b5b | 399 | } |
87057e24 | 400 | #endif |
bdf10b5b | 401 | |
9ca45586 | 402 | int dns_name_concat(const char *a, const char *b, char **_ret) { |
74b2466e LP |
403 | _cleanup_free_ char *ret = NULL; |
404 | size_t n = 0, allocated = 0; | |
3a519900 | 405 | const char *p; |
74b2466e LP |
406 | bool first = true; |
407 | int r; | |
408 | ||
3a519900 LP |
409 | if (a) |
410 | p = a; | |
411 | else if (b) { | |
412 | p = b; | |
413 | b = NULL; | |
414 | } else | |
415 | goto finish; | |
74b2466e LP |
416 | |
417 | for (;;) { | |
74b2466e LP |
418 | char label[DNS_LABEL_MAX]; |
419 | ||
420 | r = dns_label_unescape(&p, label, sizeof(label)); | |
421 | if (r < 0) | |
422 | return r; | |
423 | if (r == 0) { | |
424 | if (*p != 0) | |
425 | return -EINVAL; | |
9ca45586 LP |
426 | |
427 | if (b) { | |
428 | /* Now continue with the second string, if there is one */ | |
429 | p = b; | |
430 | b = NULL; | |
431 | continue; | |
432 | } | |
433 | ||
74b2466e LP |
434 | break; |
435 | } | |
436 | ||
9ca45586 | 437 | if (_ret) { |
422baca0 | 438 | if (!GREEDY_REALLOC(ret, allocated, n + !first + DNS_LABEL_ESCAPED_MAX)) |
9ca45586 | 439 | return -ENOMEM; |
74b2466e | 440 | |
422baca0 LP |
441 | r = dns_label_escape(label, r, ret + n + !first, DNS_LABEL_ESCAPED_MAX); |
442 | if (r < 0) | |
443 | return r; | |
444 | ||
9ca45586 | 445 | if (!first) |
422baca0 LP |
446 | ret[n] = '.'; |
447 | } else { | |
448 | char escaped[DNS_LABEL_ESCAPED_MAX]; | |
9ca45586 | 449 | |
422baca0 LP |
450 | r = dns_label_escape(label, r, escaped, sizeof(escaped)); |
451 | if (r < 0) | |
452 | return r; | |
9ca45586 | 453 | } |
74b2466e | 454 | |
422baca0 LP |
455 | if (!first) |
456 | n++; | |
457 | else | |
458 | first = false; | |
459 | ||
74b2466e LP |
460 | n += r; |
461 | } | |
462 | ||
3a519900 | 463 | finish: |
1dfbf000 LP |
464 | if (n > DNS_HOSTNAME_MAX) |
465 | return -EINVAL; | |
466 | ||
7b9f7afc | 467 | if (_ret) { |
3a519900 LP |
468 | if (n == 0) { |
469 | /* Nothing appended? If so, generate at least a single dot, to indicate the DNS root domain */ | |
470 | if (!GREEDY_REALLOC(ret, allocated, 2)) | |
471 | return -ENOMEM; | |
472 | ||
473 | ret[n++] = '.'; | |
474 | } else { | |
475 | if (!GREEDY_REALLOC(ret, allocated, n + 1)) | |
476 | return -ENOMEM; | |
477 | } | |
9ca45586 LP |
478 | |
479 | ret[n] = 0; | |
7b9f7afc LP |
480 | *_ret = ret; |
481 | ret = NULL; | |
482 | } | |
74b2466e LP |
483 | |
484 | return 0; | |
485 | } | |
486 | ||
b826ab58 | 487 | void dns_name_hash_func(const void *s, struct siphash *state) { |
74b2466e | 488 | const char *p = s; |
74b2466e LP |
489 | int r; |
490 | ||
491 | assert(p); | |
492 | ||
d12315a4 | 493 | for (;;) { |
74b2466e LP |
494 | char label[DNS_LABEL_MAX+1]; |
495 | ||
496 | r = dns_label_unescape(&p, label, sizeof(label)); | |
497 | if (r < 0) | |
498 | break; | |
d12315a4 LP |
499 | if (r == 0) |
500 | break; | |
74b2466e | 501 | |
509eddd2 LP |
502 | ascii_strlower_n(label, r); |
503 | siphash24_compress(label, r, state); | |
d5115566 | 504 | siphash24_compress_byte(0, state); /* make sure foobar and foo.bar result in different hashes */ |
74b2466e | 505 | } |
1e2527a6 TG |
506 | |
507 | /* enforce that all names are terminated by the empty label */ | |
508 | string_hash_func("", state); | |
74b2466e LP |
509 | } |
510 | ||
511 | int dns_name_compare_func(const void *a, const void *b) { | |
5dfd7011 | 512 | const char *x, *y; |
23b298bc | 513 | int r, q; |
74b2466e LP |
514 | |
515 | assert(a); | |
516 | assert(b); | |
517 | ||
5dfd7011 TG |
518 | x = (const char *) a + strlen(a); |
519 | y = (const char *) b + strlen(b); | |
520 | ||
74b2466e | 521 | for (;;) { |
34361485 | 522 | char la[DNS_LABEL_MAX], lb[DNS_LABEL_MAX]; |
74b2466e | 523 | |
5dfd7011 | 524 | if (x == NULL && y == NULL) |
74b2466e LP |
525 | return 0; |
526 | ||
5dfd7011 TG |
527 | r = dns_label_unescape_suffix(a, &x, la, sizeof(la)); |
528 | q = dns_label_unescape_suffix(b, &y, lb, sizeof(lb)); | |
74b2466e LP |
529 | if (r < 0 || q < 0) |
530 | return r - q; | |
531 | ||
34361485 | 532 | r = ascii_strcasecmp_nn(la, r, lb, q); |
74b2466e LP |
533 | if (r != 0) |
534 | return r; | |
535 | } | |
536 | } | |
537 | ||
d5099efc MS |
538 | const struct hash_ops dns_name_hash_ops = { |
539 | .hash = dns_name_hash_func, | |
540 | .compare = dns_name_compare_func | |
541 | }; | |
542 | ||
74b2466e | 543 | int dns_name_equal(const char *x, const char *y) { |
81ec9e08 | 544 | int r, q; |
74b2466e LP |
545 | |
546 | assert(x); | |
547 | assert(y); | |
548 | ||
549 | for (;;) { | |
3095011d | 550 | char la[DNS_LABEL_MAX], lb[DNS_LABEL_MAX]; |
74b2466e | 551 | |
23b298bc | 552 | r = dns_label_unescape(&x, la, sizeof(la)); |
74b2466e LP |
553 | if (r < 0) |
554 | return r; | |
bdf10b5b | 555 | |
23b298bc | 556 | q = dns_label_unescape(&y, lb, sizeof(lb)); |
74b2466e LP |
557 | if (q < 0) |
558 | return q; | |
3b37fa73 | 559 | |
3095011d LP |
560 | if (r != q) |
561 | return false; | |
562 | if (r == 0) | |
563 | return true; | |
74b2466e | 564 | |
3095011d | 565 | if (ascii_strcasecmp_n(la, lb, r) != 0) |
74b2466e LP |
566 | return false; |
567 | } | |
568 | } | |
569 | ||
570 | int dns_name_endswith(const char *name, const char *suffix) { | |
571 | const char *n, *s, *saved_n = NULL; | |
81ec9e08 | 572 | int r, q; |
74b2466e LP |
573 | |
574 | assert(name); | |
575 | assert(suffix); | |
576 | ||
577 | n = name; | |
578 | s = suffix; | |
579 | ||
580 | for (;;) { | |
3095011d | 581 | char ln[DNS_LABEL_MAX], ls[DNS_LABEL_MAX]; |
74b2466e | 582 | |
23b298bc | 583 | r = dns_label_unescape(&n, ln, sizeof(ln)); |
74b2466e LP |
584 | if (r < 0) |
585 | return r; | |
586 | ||
587 | if (!saved_n) | |
588 | saved_n = n; | |
589 | ||
23b298bc | 590 | q = dns_label_unescape(&s, ls, sizeof(ls)); |
be754d54 LP |
591 | if (q < 0) |
592 | return q; | |
74b2466e LP |
593 | |
594 | if (r == 0 && q == 0) | |
595 | return true; | |
596 | if (r == 0 && saved_n == n) | |
597 | return false; | |
598 | ||
3095011d | 599 | if (r != q || ascii_strcasecmp_n(ln, ls, r) != 0) { |
74b2466e LP |
600 | |
601 | /* Not the same, let's jump back, and try with the next label again */ | |
602 | s = suffix; | |
ae2a15bc | 603 | n = TAKE_PTR(saved_n); |
74b2466e LP |
604 | } |
605 | } | |
606 | } | |
607 | ||
eb241cdb LP |
608 | int dns_name_startswith(const char *name, const char *prefix) { |
609 | const char *n, *p; | |
610 | int r, q; | |
611 | ||
612 | assert(name); | |
613 | assert(prefix); | |
614 | ||
615 | n = name; | |
616 | p = prefix; | |
617 | ||
618 | for (;;) { | |
619 | char ln[DNS_LABEL_MAX], lp[DNS_LABEL_MAX]; | |
620 | ||
23b298bc | 621 | r = dns_label_unescape(&p, lp, sizeof(lp)); |
eb241cdb LP |
622 | if (r < 0) |
623 | return r; | |
624 | if (r == 0) | |
625 | return true; | |
626 | ||
23b298bc | 627 | q = dns_label_unescape(&n, ln, sizeof(ln)); |
eb241cdb LP |
628 | if (q < 0) |
629 | return q; | |
630 | ||
631 | if (r != q) | |
632 | return false; | |
633 | if (ascii_strcasecmp_n(ln, lp, r) != 0) | |
634 | return false; | |
635 | } | |
636 | } | |
637 | ||
58db254a LP |
638 | int dns_name_change_suffix(const char *name, const char *old_suffix, const char *new_suffix, char **ret) { |
639 | const char *n, *s, *saved_before = NULL, *saved_after = NULL, *prefix; | |
81ec9e08 | 640 | int r, q; |
58db254a LP |
641 | |
642 | assert(name); | |
643 | assert(old_suffix); | |
644 | assert(new_suffix); | |
645 | assert(ret); | |
646 | ||
647 | n = name; | |
648 | s = old_suffix; | |
649 | ||
650 | for (;;) { | |
3095011d | 651 | char ln[DNS_LABEL_MAX], ls[DNS_LABEL_MAX]; |
58db254a LP |
652 | |
653 | if (!saved_before) | |
654 | saved_before = n; | |
655 | ||
23b298bc | 656 | r = dns_label_unescape(&n, ln, sizeof(ln)); |
58db254a LP |
657 | if (r < 0) |
658 | return r; | |
58db254a LP |
659 | |
660 | if (!saved_after) | |
661 | saved_after = n; | |
662 | ||
23b298bc | 663 | q = dns_label_unescape(&s, ls, sizeof(ls)); |
58db254a LP |
664 | if (q < 0) |
665 | return q; | |
58db254a LP |
666 | |
667 | if (r == 0 && q == 0) | |
668 | break; | |
669 | if (r == 0 && saved_after == n) { | |
670 | *ret = NULL; /* doesn't match */ | |
671 | return 0; | |
672 | } | |
673 | ||
3095011d | 674 | if (r != q || ascii_strcasecmp_n(ln, ls, r) != 0) { |
58db254a LP |
675 | |
676 | /* Not the same, let's jump back, and try with the next label again */ | |
677 | s = old_suffix; | |
678 | n = saved_after; | |
679 | saved_after = saved_before = NULL; | |
680 | } | |
681 | } | |
682 | ||
683 | /* Found it! Now generate the new name */ | |
684 | prefix = strndupa(name, saved_before - name); | |
685 | ||
686 | r = dns_name_concat(prefix, new_suffix, ret); | |
687 | if (r < 0) | |
688 | return r; | |
689 | ||
690 | return 1; | |
691 | } | |
692 | ||
ae72b22c | 693 | int dns_name_between(const char *a, const char *b, const char *c) { |
ae72b22c TG |
694 | /* Determine if b is strictly greater than a and strictly smaller than c. |
695 | We consider the order of names to be circular, so that if a is | |
696 | strictly greater than c, we consider b to be between them if it is | |
697 | either greater than a or smaller than c. This is how the canonical | |
698 | DNS name order used in NSEC records work. */ | |
699 | ||
59f2725c LP |
700 | if (dns_name_compare_func(a, c) < 0) |
701 | /* | |
702 | a and c are properly ordered: | |
703 | a<---b--->c | |
704 | */ | |
ae72b22c TG |
705 | return dns_name_compare_func(a, b) < 0 && |
706 | dns_name_compare_func(b, c) < 0; | |
707 | else | |
59f2725c LP |
708 | /* |
709 | a and c are equal or 'reversed': | |
710 | <--b--c a-----> | |
711 | or: | |
712 | <-----c a--b--> | |
713 | */ | |
ae72b22c TG |
714 | return dns_name_compare_func(b, c) < 0 || |
715 | dns_name_compare_func(a, b) < 0; | |
716 | } | |
717 | ||
74b2466e LP |
718 | int dns_name_reverse(int family, const union in_addr_union *a, char **ret) { |
719 | const uint8_t *p; | |
720 | int r; | |
721 | ||
722 | assert(a); | |
723 | assert(ret); | |
724 | ||
725 | p = (const uint8_t*) a; | |
726 | ||
727 | if (family == AF_INET) | |
728 | r = asprintf(ret, "%u.%u.%u.%u.in-addr.arpa", p[3], p[2], p[1], p[0]); | |
729 | else if (family == AF_INET6) | |
3fe1169f LP |
730 | r = asprintf(ret, "%c.%c.%c.%c.%c.%c.%c.%c.%c.%c.%c.%c.%c.%c.%c.%c.%c.%c.%c.%c.%c.%c.%c.%c.%c.%c.%c.%c.%c.%c.%c.%c.ip6.arpa", |
731 | hexchar(p[15] & 0xF), hexchar(p[15] >> 4), hexchar(p[14] & 0xF), hexchar(p[14] >> 4), | |
732 | hexchar(p[13] & 0xF), hexchar(p[13] >> 4), hexchar(p[12] & 0xF), hexchar(p[12] >> 4), | |
733 | hexchar(p[11] & 0xF), hexchar(p[11] >> 4), hexchar(p[10] & 0xF), hexchar(p[10] >> 4), | |
734 | hexchar(p[ 9] & 0xF), hexchar(p[ 9] >> 4), hexchar(p[ 8] & 0xF), hexchar(p[ 8] >> 4), | |
735 | hexchar(p[ 7] & 0xF), hexchar(p[ 7] >> 4), hexchar(p[ 6] & 0xF), hexchar(p[ 6] >> 4), | |
736 | hexchar(p[ 5] & 0xF), hexchar(p[ 5] >> 4), hexchar(p[ 4] & 0xF), hexchar(p[ 4] >> 4), | |
737 | hexchar(p[ 3] & 0xF), hexchar(p[ 3] >> 4), hexchar(p[ 2] & 0xF), hexchar(p[ 2] >> 4), | |
738 | hexchar(p[ 1] & 0xF), hexchar(p[ 1] >> 4), hexchar(p[ 0] & 0xF), hexchar(p[ 0] >> 4)); | |
74b2466e LP |
739 | else |
740 | return -EAFNOSUPPORT; | |
741 | if (r < 0) | |
742 | return -ENOMEM; | |
743 | ||
744 | return 0; | |
745 | } | |
746 | ||
b914e211 LP |
747 | int dns_name_address(const char *p, int *family, union in_addr_union *address) { |
748 | int r; | |
749 | ||
750 | assert(p); | |
751 | assert(family); | |
752 | assert(address); | |
753 | ||
754 | r = dns_name_endswith(p, "in-addr.arpa"); | |
755 | if (r < 0) | |
756 | return r; | |
757 | if (r > 0) { | |
758 | uint8_t a[4]; | |
759 | unsigned i; | |
760 | ||
761 | for (i = 0; i < ELEMENTSOF(a); i++) { | |
762 | char label[DNS_LABEL_MAX+1]; | |
763 | ||
764 | r = dns_label_unescape(&p, label, sizeof(label)); | |
765 | if (r < 0) | |
766 | return r; | |
767 | if (r == 0) | |
768 | return -EINVAL; | |
769 | if (r > 3) | |
770 | return -EINVAL; | |
771 | ||
772 | r = safe_atou8(label, &a[i]); | |
773 | if (r < 0) | |
774 | return r; | |
775 | } | |
776 | ||
777 | r = dns_name_equal(p, "in-addr.arpa"); | |
778 | if (r <= 0) | |
779 | return r; | |
780 | ||
781 | *family = AF_INET; | |
782 | address->in.s_addr = htobe32(((uint32_t) a[3] << 24) | | |
783 | ((uint32_t) a[2] << 16) | | |
784 | ((uint32_t) a[1] << 8) | | |
785 | (uint32_t) a[0]); | |
786 | ||
787 | return 1; | |
788 | } | |
789 | ||
790 | r = dns_name_endswith(p, "ip6.arpa"); | |
791 | if (r < 0) | |
792 | return r; | |
793 | if (r > 0) { | |
794 | struct in6_addr a; | |
795 | unsigned i; | |
796 | ||
797 | for (i = 0; i < ELEMENTSOF(a.s6_addr); i++) { | |
798 | char label[DNS_LABEL_MAX+1]; | |
799 | int x, y; | |
800 | ||
801 | r = dns_label_unescape(&p, label, sizeof(label)); | |
802 | if (r <= 0) | |
803 | return r; | |
804 | if (r != 1) | |
805 | return -EINVAL; | |
806 | x = unhexchar(label[0]); | |
807 | if (x < 0) | |
808 | return -EINVAL; | |
809 | ||
810 | r = dns_label_unescape(&p, label, sizeof(label)); | |
811 | if (r <= 0) | |
812 | return r; | |
813 | if (r != 1) | |
814 | return -EINVAL; | |
815 | y = unhexchar(label[0]); | |
816 | if (y < 0) | |
817 | return -EINVAL; | |
818 | ||
819 | a.s6_addr[ELEMENTSOF(a.s6_addr) - i - 1] = (uint8_t) y << 4 | (uint8_t) x; | |
820 | } | |
821 | ||
822 | r = dns_name_equal(p, "ip6.arpa"); | |
823 | if (r <= 0) | |
824 | return r; | |
825 | ||
826 | *family = AF_INET6; | |
827 | address->in6 = a; | |
828 | return 1; | |
829 | } | |
830 | ||
831 | return 0; | |
832 | } | |
833 | ||
dc477e73 | 834 | bool dns_name_is_root(const char *name) { |
74b2466e LP |
835 | |
836 | assert(name); | |
837 | ||
dc477e73 LP |
838 | /* There are exactly two ways to encode the root domain name: |
839 | * as empty string, or with a single dot. */ | |
74b2466e | 840 | |
dc477e73 | 841 | return STR_IN_SET(name, "", "."); |
74b2466e LP |
842 | } |
843 | ||
dc477e73 | 844 | bool dns_name_is_single_label(const char *name) { |
74b2466e LP |
845 | int r; |
846 | ||
847 | assert(name); | |
848 | ||
f6fbd9c2 | 849 | r = dns_name_parent(&name); |
dc477e73 LP |
850 | if (r <= 0) |
851 | return false; | |
74b2466e | 852 | |
dc477e73 | 853 | return dns_name_is_root(name); |
74b2466e | 854 | } |
54adabf7 | 855 | |
50dee79b | 856 | /* Encode a domain name according to RFC 1035 Section 3.1, without compression */ |
3cd03457 | 857 | int dns_name_to_wire_format(const char *domain, uint8_t *buffer, size_t len, bool canonical) { |
c6cefd13 | 858 | uint8_t *label_length, *out; |
54adabf7 BG |
859 | int r; |
860 | ||
c6cefd13 LP |
861 | assert(domain); |
862 | assert(buffer); | |
54adabf7 BG |
863 | |
864 | out = buffer; | |
865 | ||
866 | do { | |
50dee79b | 867 | /* Reserve a byte for label length */ |
c6cefd13 | 868 | if (len <= 0) |
54adabf7 BG |
869 | return -ENOBUFS; |
870 | len--; | |
871 | label_length = out; | |
872 | out++; | |
873 | ||
50dee79b LP |
874 | /* Convert and copy a single label. Note that |
875 | * dns_label_unescape() returns 0 when it hits the end | |
876 | * of the domain name, which we rely on here to encode | |
877 | * the trailing NUL byte. */ | |
54adabf7 BG |
878 | r = dns_label_unescape(&domain, (char *) out, len); |
879 | if (r < 0) | |
880 | return r; | |
881 | ||
b577e3d5 LP |
882 | /* Optionally, output the name in DNSSEC canonical |
883 | * format, as described in RFC 4034, section 6.2. Or | |
884 | * in other words: in lower-case. */ | |
885 | if (canonical) | |
886 | ascii_strlower_n((char*) out, (size_t) r); | |
3cd03457 | 887 | |
50dee79b | 888 | /* Fill label length, move forward */ |
54adabf7 BG |
889 | *label_length = r; |
890 | out += r; | |
891 | len -= r; | |
50dee79b | 892 | |
54adabf7 BG |
893 | } while (r != 0); |
894 | ||
50dee79b LP |
895 | /* Verify the maximum size of the encoded name. The trailing |
896 | * dot + NUL byte account are included this time, hence | |
897 | * compare against DNS_HOSTNAME_MAX + 2 (which is 255) this | |
898 | * time. */ | |
899 | if (out - buffer > DNS_HOSTNAME_MAX + 2) | |
900 | return -EINVAL; | |
901 | ||
54adabf7 BG |
902 | return out - buffer; |
903 | } | |
0a49b6b6 | 904 | |
0e8eedbb LP |
905 | static bool srv_type_label_is_valid(const char *label, size_t n) { |
906 | size_t k; | |
907 | ||
908 | assert(label); | |
909 | ||
910 | if (n < 2) /* Label needs to be at least 2 chars long */ | |
911 | return false; | |
912 | ||
913 | if (label[0] != '_') /* First label char needs to be underscore */ | |
914 | return false; | |
915 | ||
916 | /* Second char must be a letter */ | |
917 | if (!(label[1] >= 'A' && label[1] <= 'Z') && | |
918 | !(label[1] >= 'a' && label[1] <= 'z')) | |
919 | return false; | |
920 | ||
921 | /* Third and further chars must be alphanumeric or a hyphen */ | |
922 | for (k = 2; k < n; k++) { | |
923 | if (!(label[k] >= 'A' && label[k] <= 'Z') && | |
924 | !(label[k] >= 'a' && label[k] <= 'z') && | |
925 | !(label[k] >= '0' && label[k] <= '9') && | |
926 | label[k] != '-') | |
927 | return false; | |
928 | } | |
929 | ||
930 | return true; | |
931 | } | |
932 | ||
7e8131e9 | 933 | bool dns_srv_type_is_valid(const char *name) { |
0a49b6b6 LP |
934 | unsigned c = 0; |
935 | int r; | |
936 | ||
937 | if (!name) | |
7e8131e9 | 938 | return false; |
0a49b6b6 LP |
939 | |
940 | for (;;) { | |
941 | char label[DNS_LABEL_MAX]; | |
0a49b6b6 LP |
942 | |
943 | /* This more or less implements RFC 6335, Section 5.1 */ | |
944 | ||
945 | r = dns_label_unescape(&name, label, sizeof(label)); | |
0a49b6b6 | 946 | if (r < 0) |
7e8131e9 | 947 | return false; |
0a49b6b6 | 948 | if (r == 0) |
0e8eedbb | 949 | break; |
0a49b6b6 | 950 | |
0e8eedbb | 951 | if (c >= 2) |
7e8131e9 | 952 | return false; |
0a49b6b6 | 953 | |
0e8eedbb | 954 | if (!srv_type_label_is_valid(label, r)) |
7e8131e9 | 955 | return false; |
0a49b6b6 LP |
956 | |
957 | c++; | |
958 | } | |
0e8eedbb LP |
959 | |
960 | return c == 2; /* exactly two labels */ | |
0a49b6b6 LP |
961 | } |
962 | ||
154ae087 DR |
963 | bool dnssd_srv_type_is_valid(const char *name) { |
964 | return dns_srv_type_is_valid(name) && | |
965 | ((dns_name_endswith(name, "_tcp") > 0) || | |
966 | (dns_name_endswith(name, "_udp") > 0)); /* Specific to DNS-SD. RFC 6763, Section 7 */ | |
967 | } | |
968 | ||
0a49b6b6 LP |
969 | bool dns_service_name_is_valid(const char *name) { |
970 | size_t l; | |
971 | ||
972 | /* This more or less implements RFC 6763, Section 4.1.1 */ | |
973 | ||
974 | if (!name) | |
975 | return false; | |
976 | ||
977 | if (!utf8_is_valid(name)) | |
978 | return false; | |
979 | ||
980 | if (string_has_cc(name, NULL)) | |
981 | return false; | |
982 | ||
983 | l = strlen(name); | |
984 | if (l <= 0) | |
985 | return false; | |
986 | if (l > 63) | |
987 | return false; | |
988 | ||
989 | return true; | |
990 | } | |
0e8eedbb LP |
991 | |
992 | int dns_service_join(const char *name, const char *type, const char *domain, char **ret) { | |
422baca0 LP |
993 | char escaped[DNS_LABEL_ESCAPED_MAX]; |
994 | _cleanup_free_ char *n = NULL; | |
0e8eedbb LP |
995 | int r; |
996 | ||
997 | assert(type); | |
998 | assert(domain); | |
999 | assert(ret); | |
1000 | ||
7e8131e9 | 1001 | if (!dns_srv_type_is_valid(type)) |
0e8eedbb LP |
1002 | return -EINVAL; |
1003 | ||
1004 | if (!name) | |
1005 | return dns_name_concat(type, domain, ret); | |
1006 | ||
1007 | if (!dns_service_name_is_valid(name)) | |
1008 | return -EINVAL; | |
1009 | ||
422baca0 | 1010 | r = dns_label_escape(name, strlen(name), escaped, sizeof(escaped)); |
0e8eedbb LP |
1011 | if (r < 0) |
1012 | return r; | |
1013 | ||
1014 | r = dns_name_concat(type, domain, &n); | |
1015 | if (r < 0) | |
1016 | return r; | |
1017 | ||
1018 | return dns_name_concat(escaped, n, ret); | |
1019 | } | |
1020 | ||
1021 | static bool dns_service_name_label_is_valid(const char *label, size_t n) { | |
1022 | char *s; | |
1023 | ||
1024 | assert(label); | |
1025 | ||
1026 | if (memchr(label, 0, n)) | |
1027 | return false; | |
1028 | ||
1029 | s = strndupa(label, n); | |
1030 | return dns_service_name_is_valid(s); | |
1031 | } | |
1032 | ||
1033 | int dns_service_split(const char *joined, char **_name, char **_type, char **_domain) { | |
1034 | _cleanup_free_ char *name = NULL, *type = NULL, *domain = NULL; | |
1035 | const char *p = joined, *q = NULL, *d = NULL; | |
1036 | char a[DNS_LABEL_MAX], b[DNS_LABEL_MAX], c[DNS_LABEL_MAX]; | |
1037 | int an, bn, cn, r; | |
1038 | unsigned x = 0; | |
1039 | ||
1040 | assert(joined); | |
1041 | ||
1042 | /* Get first label from the full name */ | |
1043 | an = dns_label_unescape(&p, a, sizeof(a)); | |
1044 | if (an < 0) | |
1045 | return an; | |
1046 | ||
1047 | if (an > 0) { | |
1048 | x++; | |
1049 | ||
1050 | /* If there was a first label, try to get the second one */ | |
1051 | bn = dns_label_unescape(&p, b, sizeof(b)); | |
1052 | if (bn < 0) | |
1053 | return bn; | |
1054 | ||
1055 | if (bn > 0) { | |
1056 | x++; | |
1057 | ||
1058 | /* If there was a second label, try to get the third one */ | |
1059 | q = p; | |
1060 | cn = dns_label_unescape(&p, c, sizeof(c)); | |
1061 | if (cn < 0) | |
1062 | return cn; | |
1063 | ||
1064 | if (cn > 0) | |
1065 | x++; | |
1066 | } else | |
1067 | cn = 0; | |
1068 | } else | |
1069 | an = 0; | |
1070 | ||
1071 | if (x >= 2 && srv_type_label_is_valid(b, bn)) { | |
1072 | ||
1073 | if (x >= 3 && srv_type_label_is_valid(c, cn)) { | |
1074 | ||
1075 | if (dns_service_name_label_is_valid(a, an)) { | |
0e8eedbb LP |
1076 | /* OK, got <name> . <type> . <type2> . <domain> */ |
1077 | ||
1078 | name = strndup(a, an); | |
1079 | if (!name) | |
1080 | return -ENOMEM; | |
1081 | ||
605405c6 | 1082 | type = strjoin(b, ".", c); |
0e8eedbb LP |
1083 | if (!type) |
1084 | return -ENOMEM; | |
0e8eedbb LP |
1085 | |
1086 | d = p; | |
1087 | goto finish; | |
1088 | } | |
1089 | ||
1090 | } else if (srv_type_label_is_valid(a, an)) { | |
1091 | ||
1092 | /* OK, got <type> . <type2> . <domain> */ | |
1093 | ||
1094 | name = NULL; | |
1095 | ||
605405c6 | 1096 | type = strjoin(a, ".", b); |
0e8eedbb LP |
1097 | if (!type) |
1098 | return -ENOMEM; | |
0e8eedbb LP |
1099 | |
1100 | d = q; | |
1101 | goto finish; | |
1102 | } | |
1103 | } | |
1104 | ||
1105 | name = NULL; | |
1106 | type = NULL; | |
1107 | d = joined; | |
1108 | ||
1109 | finish: | |
1110 | r = dns_name_normalize(d, &domain); | |
1111 | if (r < 0) | |
1112 | return r; | |
1113 | ||
1114 | if (_domain) { | |
1115 | *_domain = domain; | |
1116 | domain = NULL; | |
1117 | } | |
1118 | ||
1119 | if (_type) { | |
1120 | *_type = type; | |
1121 | type = NULL; | |
1122 | } | |
1123 | ||
1124 | if (_name) { | |
1125 | *_name = name; | |
1126 | name = NULL; | |
1127 | } | |
1128 | ||
1129 | return 0; | |
1130 | } | |
e7ff0e0b | 1131 | |
b9282bc1 | 1132 | static int dns_name_build_suffix_table(const char *name, const char*table[]) { |
e7ff0e0b | 1133 | const char *p; |
b9282bc1 | 1134 | unsigned n = 0; |
e7ff0e0b LP |
1135 | int r; |
1136 | ||
1137 | assert(name); | |
b9282bc1 | 1138 | assert(table); |
e7ff0e0b LP |
1139 | |
1140 | p = name; | |
1141 | for (;;) { | |
1142 | if (n > DNS_N_LABELS_MAX) | |
1143 | return -EINVAL; | |
1144 | ||
b9282bc1 | 1145 | table[n] = p; |
e7ff0e0b LP |
1146 | r = dns_name_parent(&p); |
1147 | if (r < 0) | |
1148 | return r; | |
1149 | if (r == 0) | |
1150 | break; | |
1151 | ||
1152 | n++; | |
1153 | } | |
1154 | ||
b9282bc1 LP |
1155 | return (int) n; |
1156 | } | |
1157 | ||
1158 | int dns_name_suffix(const char *name, unsigned n_labels, const char **ret) { | |
1159 | const char* labels[DNS_N_LABELS_MAX+1]; | |
1160 | int n; | |
1161 | ||
1162 | assert(name); | |
1163 | assert(ret); | |
1164 | ||
1165 | n = dns_name_build_suffix_table(name, labels); | |
1166 | if (n < 0) | |
1167 | return n; | |
1168 | ||
1169 | if ((unsigned) n < n_labels) | |
e7ff0e0b LP |
1170 | return -EINVAL; |
1171 | ||
1172 | *ret = labels[n - n_labels]; | |
1173 | return (int) (n - n_labels); | |
1174 | } | |
1175 | ||
97c67192 LP |
1176 | int dns_name_skip(const char *a, unsigned n_labels, const char **ret) { |
1177 | int r; | |
1178 | ||
1179 | assert(a); | |
1180 | assert(ret); | |
1181 | ||
313cefa1 | 1182 | for (; n_labels > 0; n_labels--) { |
97c67192 LP |
1183 | r = dns_name_parent(&a); |
1184 | if (r < 0) | |
1185 | return r; | |
1186 | if (r == 0) { | |
1187 | *ret = ""; | |
1188 | return 0; | |
1189 | } | |
1190 | } | |
1191 | ||
1192 | *ret = a; | |
1193 | return 1; | |
1194 | } | |
1195 | ||
e7ff0e0b LP |
1196 | int dns_name_count_labels(const char *name) { |
1197 | unsigned n = 0; | |
1198 | const char *p; | |
1199 | int r; | |
1200 | ||
1201 | assert(name); | |
1202 | ||
1203 | p = name; | |
1204 | for (;;) { | |
1205 | r = dns_name_parent(&p); | |
1206 | if (r < 0) | |
1207 | return r; | |
1208 | if (r == 0) | |
1209 | break; | |
1210 | ||
1211 | if (n >= DNS_N_LABELS_MAX) | |
1212 | return -EINVAL; | |
1213 | ||
1214 | n++; | |
1215 | } | |
1216 | ||
1217 | return (int) n; | |
1218 | } | |
db5b0e92 LP |
1219 | |
1220 | int dns_name_equal_skip(const char *a, unsigned n_labels, const char *b) { | |
1221 | int r; | |
1222 | ||
1223 | assert(a); | |
1224 | assert(b); | |
1225 | ||
97c67192 LP |
1226 | r = dns_name_skip(a, n_labels, &a); |
1227 | if (r <= 0) | |
1228 | return r; | |
db5b0e92 LP |
1229 | |
1230 | return dns_name_equal(a, b); | |
1231 | } | |
b9282bc1 LP |
1232 | |
1233 | int dns_name_common_suffix(const char *a, const char *b, const char **ret) { | |
1234 | const char *a_labels[DNS_N_LABELS_MAX+1], *b_labels[DNS_N_LABELS_MAX+1]; | |
1235 | int n = 0, m = 0, k = 0, r, q; | |
1236 | ||
1237 | assert(a); | |
1238 | assert(b); | |
1239 | assert(ret); | |
1240 | ||
1241 | /* Determines the common suffix of domain names a and b */ | |
1242 | ||
1243 | n = dns_name_build_suffix_table(a, a_labels); | |
1244 | if (n < 0) | |
1245 | return n; | |
1246 | ||
1247 | m = dns_name_build_suffix_table(b, b_labels); | |
1248 | if (m < 0) | |
1249 | return m; | |
1250 | ||
1251 | for (;;) { | |
1252 | char la[DNS_LABEL_MAX], lb[DNS_LABEL_MAX]; | |
1253 | const char *x, *y; | |
1254 | ||
1255 | if (k >= n || k >= m) { | |
1256 | *ret = a_labels[n - k]; | |
1257 | return 0; | |
1258 | } | |
1259 | ||
1260 | x = a_labels[n - 1 - k]; | |
23b298bc | 1261 | r = dns_label_unescape(&x, la, sizeof(la)); |
b9282bc1 LP |
1262 | if (r < 0) |
1263 | return r; | |
1264 | ||
1265 | y = b_labels[m - 1 - k]; | |
23b298bc | 1266 | q = dns_label_unescape(&y, lb, sizeof(lb)); |
b9282bc1 LP |
1267 | if (q < 0) |
1268 | return q; | |
1269 | ||
1270 | if (r != q || ascii_strcasecmp_n(la, lb, r) != 0) { | |
1271 | *ret = a_labels[n - k]; | |
1272 | return 0; | |
1273 | } | |
1274 | ||
1275 | k++; | |
1276 | } | |
1277 | } | |
0cf40f55 LP |
1278 | |
1279 | int dns_name_apply_idna(const char *name, char **ret) { | |
87057e24 ZJS |
1280 | /* Return negative on error, 0 if not implemented, positive on success. */ |
1281 | ||
349cc4a5 | 1282 | #if HAVE_LIBIDN2 |
87057e24 | 1283 | int r; |
0926f348 | 1284 | _cleanup_free_ char *t = NULL; |
87057e24 ZJS |
1285 | |
1286 | assert(name); | |
1287 | assert(ret); | |
1288 | ||
0926f348 | 1289 | r = idn2_lookup_u8((uint8_t*) name, (uint8_t**) &t, |
87057e24 | 1290 | IDN2_NFC_INPUT | IDN2_NONTRANSITIONAL); |
0926f348 ZJS |
1291 | log_debug("idn2_lookup_u8: %s → %s", name, t); |
1292 | if (r == IDN2_OK) { | |
1293 | if (!startswith(name, "xn--")) { | |
1294 | _cleanup_free_ char *s = NULL; | |
1295 | ||
1296 | r = idn2_to_unicode_8z8z(t, &s, 0); | |
1297 | if (r != IDN2_OK) { | |
1298 | log_debug("idn2_to_unicode_8z8z(\"%s\") failed: %d/%s", | |
1299 | t, r, idn2_strerror(r)); | |
1300 | return 0; | |
1301 | } | |
1302 | ||
1303 | if (!streq_ptr(name, s)) { | |
1304 | log_debug("idn2 roundtrip failed: \"%s\" → \"%s\" → \"%s\", ignoring.", | |
1305 | name, t, s); | |
1306 | return 0; | |
1307 | } | |
1308 | } | |
1309 | ||
1310 | *ret = t; | |
1311 | t = NULL; | |
87057e24 | 1312 | return 1; /* *ret has been written */ |
0926f348 ZJS |
1313 | } |
1314 | ||
1315 | log_debug("idn2_lookup_u8(\"%s\") failed: %d/%s", name, r, idn2_strerror(r)); | |
ad1f3fe6 ZJS |
1316 | if (r == IDN2_2HYPHEN) |
1317 | /* The name has two hypens — forbidden by IDNA2008 in some cases */ | |
1318 | return 0; | |
1319 | if (IN_SET(r, IDN2_TOO_BIG_DOMAIN, IDN2_TOO_BIG_LABEL)) | |
87057e24 | 1320 | return -ENOSPC; |
ad1f3fe6 | 1321 | return -EINVAL; |
349cc4a5 | 1322 | #elif HAVE_LIBIDN |
0cf40f55 LP |
1323 | _cleanup_free_ char *buf = NULL; |
1324 | size_t n = 0, allocated = 0; | |
1325 | bool first = true; | |
1326 | int r, q; | |
1327 | ||
1328 | assert(name); | |
1329 | assert(ret); | |
1330 | ||
1331 | for (;;) { | |
1332 | char label[DNS_LABEL_MAX]; | |
1333 | ||
1334 | r = dns_label_unescape(&name, label, sizeof(label)); | |
1335 | if (r < 0) | |
1336 | return r; | |
1337 | if (r == 0) | |
1338 | break; | |
1339 | ||
1340 | q = dns_label_apply_idna(label, r, label, sizeof(label)); | |
1341 | if (q < 0) | |
1342 | return q; | |
1343 | if (q > 0) | |
1344 | r = q; | |
1345 | ||
1346 | if (!GREEDY_REALLOC(buf, allocated, n + !first + DNS_LABEL_ESCAPED_MAX)) | |
1347 | return -ENOMEM; | |
1348 | ||
1349 | r = dns_label_escape(label, r, buf + n + !first, DNS_LABEL_ESCAPED_MAX); | |
1350 | if (r < 0) | |
1351 | return r; | |
1352 | ||
1353 | if (first) | |
1354 | first = false; | |
1355 | else | |
1356 | buf[n++] = '.'; | |
1357 | ||
ad1f3fe6 | 1358 | n += r; |
0cf40f55 LP |
1359 | } |
1360 | ||
1361 | if (n > DNS_HOSTNAME_MAX) | |
1362 | return -EINVAL; | |
1363 | ||
1364 | if (!GREEDY_REALLOC(buf, allocated, n + 1)) | |
1365 | return -ENOMEM; | |
1366 | ||
1367 | buf[n] = 0; | |
1368 | *ret = buf; | |
1369 | buf = NULL; | |
1370 | ||
ad1f3fe6 | 1371 | return 1; |
87057e24 ZJS |
1372 | #else |
1373 | return 0; | |
1374 | #endif | |
0cf40f55 | 1375 | } |
08a4849e LP |
1376 | |
1377 | int dns_name_is_valid_or_address(const char *name) { | |
1378 | /* Returns > 0 if the specified name is either a valid IP address formatted as string or a valid DNS name */ | |
1379 | ||
1380 | if (isempty(name)) | |
1381 | return 0; | |
1382 | ||
1383 | if (in_addr_from_string_auto(name, NULL, NULL) >= 0) | |
1384 | return 1; | |
1385 | ||
1386 | return dns_name_is_valid(name); | |
1387 | } |