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Commit | Line | Data |
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74b2466e LP |
1 | /*** |
2 | This file is part of systemd. | |
3 | ||
4 | Copyright 2014 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 | ||
349cc4a5 | 20 | #if HAVE_LIBIDN2 |
87057e24 | 21 | # include <idn2.h> |
349cc4a5 | 22 | #elif HAVE_LIBIDN |
87057e24 ZJS |
23 | # include <idna.h> |
24 | # include <stringprep.h> | |
bdf10b5b LP |
25 | #endif |
26 | ||
a8fbdf54 TA |
27 | #include <endian.h> |
28 | #include <netinet/in.h> | |
29 | #include <stdio.h> | |
30 | #include <string.h> | |
31 | #include <sys/socket.h> | |
32 | ||
b5efdb8a | 33 | #include "alloc-util.h" |
4ad7f276 | 34 | #include "dns-domain.h" |
a8fbdf54 | 35 | #include "hashmap.h" |
e4e73a63 | 36 | #include "hexdecoct.h" |
a8fbdf54 TA |
37 | #include "in-addr-util.h" |
38 | #include "macro.h" | |
6bedfcbb LP |
39 | #include "parse-util.h" |
40 | #include "string-util.h" | |
dc477e73 | 41 | #include "strv.h" |
0a49b6b6 | 42 | #include "utf8.h" |
74b2466e LP |
43 | |
44 | int dns_label_unescape(const char **name, char *dest, size_t sz) { | |
45 | const char *n; | |
46 | char *d; | |
47 | int r = 0; | |
48 | ||
49 | assert(name); | |
50 | assert(*name); | |
74b2466e LP |
51 | |
52 | n = *name; | |
53 | d = dest; | |
54 | ||
55 | for (;;) { | |
56 | if (*n == '.') { | |
57 | n++; | |
58 | break; | |
59 | } | |
60 | ||
61 | if (*n == 0) | |
62 | break; | |
63 | ||
1fa65c59 LP |
64 | if (r >= DNS_LABEL_MAX) |
65 | return -EINVAL; | |
66 | ||
37ade128 LP |
67 | if (sz <= 0) |
68 | return -ENOBUFS; | |
69 | ||
74b2466e LP |
70 | if (*n == '\\') { |
71 | /* Escaped character */ | |
72 | ||
73 | n++; | |
74 | ||
75 | if (*n == 0) | |
76 | /* Ending NUL */ | |
77 | return -EINVAL; | |
78 | ||
4c701096 | 79 | else if (IN_SET(*n, '\\', '.')) { |
74b2466e | 80 | /* Escaped backslash or dot */ |
f7455baa LP |
81 | |
82 | if (d) | |
83 | *(d++) = *n; | |
74b2466e LP |
84 | sz--; |
85 | r++; | |
f7455baa | 86 | n++; |
74b2466e LP |
87 | |
88 | } else if (n[0] >= '0' && n[0] <= '9') { | |
89 | unsigned k; | |
90 | ||
91 | /* Escaped literal ASCII character */ | |
92 | ||
93 | if (!(n[1] >= '0' && n[1] <= '9') || | |
94 | !(n[2] >= '0' && n[2] <= '9')) | |
95 | return -EINVAL; | |
96 | ||
97 | k = ((unsigned) (n[0] - '0') * 100) + | |
98 | ((unsigned) (n[1] - '0') * 10) + | |
99 | ((unsigned) (n[2] - '0')); | |
100 | ||
c7feab76 LP |
101 | /* Don't allow anything that doesn't |
102 | * fit in 8bit. Note that we do allow | |
103 | * control characters, as some servers | |
104 | * (e.g. cloudflare) are happy to | |
105 | * generate labels with them | |
106 | * inside. */ | |
107 | if (k > 255) | |
74b2466e LP |
108 | return -EINVAL; |
109 | ||
f7455baa LP |
110 | if (d) |
111 | *(d++) = (char) k; | |
74b2466e LP |
112 | sz--; |
113 | r++; | |
114 | ||
115 | n += 3; | |
116 | } else | |
117 | return -EINVAL; | |
118 | ||
07bed172 | 119 | } else if ((uint8_t) *n >= (uint8_t) ' ' && *n != 127) { |
74b2466e LP |
120 | |
121 | /* Normal character */ | |
f7455baa LP |
122 | |
123 | if (d) | |
124 | *(d++) = *n; | |
74b2466e LP |
125 | sz--; |
126 | r++; | |
f7455baa | 127 | n++; |
74b2466e LP |
128 | } else |
129 | return -EINVAL; | |
130 | } | |
131 | ||
132 | /* Empty label that is not at the end? */ | |
133 | if (r == 0 && *n) | |
134 | return -EINVAL; | |
135 | ||
f35c467d MP |
136 | /* More than one trailing dot? */ |
137 | if (*n == '.') | |
138 | return -EINVAL; | |
139 | ||
f7455baa | 140 | if (sz >= 1 && d) |
74b2466e LP |
141 | *d = 0; |
142 | ||
143 | *name = n; | |
144 | return r; | |
145 | } | |
146 | ||
642900d3 TG |
147 | /* @label_terminal: terminal character of a label, updated to point to the terminal character of |
148 | * the previous label (always skipping one dot) or to NULL if there are no more | |
149 | * labels. */ | |
150 | int dns_label_unescape_suffix(const char *name, const char **label_terminal, char *dest, size_t sz) { | |
151 | const char *terminal; | |
152 | int r; | |
153 | ||
154 | assert(name); | |
155 | assert(label_terminal); | |
156 | assert(dest); | |
157 | ||
158 | /* no more labels */ | |
159 | if (!*label_terminal) { | |
160 | if (sz >= 1) | |
161 | *dest = 0; | |
162 | ||
163 | return 0; | |
164 | } | |
165 | ||
56512859 | 166 | terminal = *label_terminal; |
4c701096 | 167 | assert(IN_SET(*terminal, 0, '.')); |
642900d3 | 168 | |
56512859 LP |
169 | /* Skip current terminal character (and accept domain names ending it ".") */ |
170 | if (*terminal == 0) | |
171 | terminal--; | |
172 | if (terminal >= name && *terminal == '.') | |
173 | terminal--; | |
642900d3 | 174 | |
56512859 | 175 | /* Point name to the last label, and terminal to the preceding terminal symbol (or make it a NULL pointer) */ |
642900d3 TG |
176 | for (;;) { |
177 | if (terminal < name) { | |
56512859 | 178 | /* Reached the first label, so indicate that there are no more */ |
642900d3 TG |
179 | terminal = NULL; |
180 | break; | |
181 | } | |
182 | ||
56512859 | 183 | /* Find the start of the last label */ |
642900d3 TG |
184 | if (*terminal == '.') { |
185 | const char *y; | |
186 | unsigned slashes = 0; | |
187 | ||
188 | for (y = terminal - 1; y >= name && *y == '\\'; y--) | |
313cefa1 | 189 | slashes++; |
642900d3 TG |
190 | |
191 | if (slashes % 2 == 0) { | |
56512859 | 192 | /* The '.' was not escaped */ |
642900d3 TG |
193 | name = terminal + 1; |
194 | break; | |
195 | } else { | |
196 | terminal = y; | |
197 | continue; | |
198 | } | |
199 | } | |
200 | ||
313cefa1 | 201 | terminal--; |
642900d3 TG |
202 | } |
203 | ||
204 | r = dns_label_unescape(&name, dest, sz); | |
205 | if (r < 0) | |
206 | return r; | |
207 | ||
208 | *label_terminal = terminal; | |
209 | ||
210 | return r; | |
211 | } | |
212 | ||
422baca0 | 213 | int dns_label_escape(const char *p, size_t l, char *dest, size_t sz) { |
74b2466e | 214 | char *q; |
74b2466e | 215 | |
3b37fa73 LP |
216 | /* DNS labels must be between 1 and 63 characters long. A |
217 | * zero-length label does not exist. See RFC 2182, Section | |
218 | * 11. */ | |
219 | ||
220 | if (l <= 0 || l > DNS_LABEL_MAX) | |
1fa65c59 | 221 | return -EINVAL; |
422baca0 | 222 | if (sz < 1) |
37ade128 | 223 | return -ENOBUFS; |
1fa65c59 | 224 | |
422baca0 LP |
225 | assert(p); |
226 | assert(dest); | |
74b2466e | 227 | |
422baca0 | 228 | q = dest; |
74b2466e LP |
229 | while (l > 0) { |
230 | ||
4c701096 | 231 | if (IN_SET(*p, '.', '\\')) { |
74b2466e | 232 | |
3b37fa73 LP |
233 | /* Dot or backslash */ |
234 | ||
422baca0 | 235 | if (sz < 3) |
37ade128 | 236 | return -ENOBUFS; |
422baca0 | 237 | |
74b2466e LP |
238 | *(q++) = '\\'; |
239 | *(q++) = *p; | |
240 | ||
422baca0 LP |
241 | sz -= 2; |
242 | ||
4c701096 | 243 | } else if (IN_SET(*p, '_', '-') || |
74b2466e LP |
244 | (*p >= '0' && *p <= '9') || |
245 | (*p >= 'a' && *p <= 'z') || | |
246 | (*p >= 'A' && *p <= 'Z')) { | |
247 | ||
248 | /* Proper character */ | |
422baca0 LP |
249 | |
250 | if (sz < 2) | |
37ade128 | 251 | return -ENOBUFS; |
422baca0 | 252 | |
74b2466e | 253 | *(q++) = *p; |
422baca0 LP |
254 | sz -= 1; |
255 | ||
c7feab76 | 256 | } else { |
74b2466e LP |
257 | |
258 | /* Everything else */ | |
422baca0 LP |
259 | |
260 | if (sz < 5) | |
37ade128 | 261 | return -ENOBUFS; |
422baca0 | 262 | |
74b2466e | 263 | *(q++) = '\\'; |
07bed172 LP |
264 | *(q++) = '0' + (char) ((uint8_t) *p / 100); |
265 | *(q++) = '0' + (char) (((uint8_t) *p / 10) % 10); | |
266 | *(q++) = '0' + (char) ((uint8_t) *p % 10); | |
74b2466e | 267 | |
422baca0 | 268 | sz -= 4; |
c7feab76 | 269 | } |
74b2466e LP |
270 | |
271 | p++; | |
272 | l--; | |
273 | } | |
274 | ||
275 | *q = 0; | |
422baca0 LP |
276 | return (int) (q - dest); |
277 | } | |
278 | ||
279 | int dns_label_escape_new(const char *p, size_t l, char **ret) { | |
280 | _cleanup_free_ char *s = NULL; | |
281 | int r; | |
282 | ||
283 | assert(p); | |
284 | assert(ret); | |
285 | ||
3b37fa73 | 286 | if (l <= 0 || l > DNS_LABEL_MAX) |
422baca0 LP |
287 | return -EINVAL; |
288 | ||
289 | s = new(char, DNS_LABEL_ESCAPED_MAX); | |
290 | if (!s) | |
291 | return -ENOMEM; | |
292 | ||
293 | r = dns_label_escape(p, l, s, DNS_LABEL_ESCAPED_MAX); | |
294 | if (r < 0) | |
295 | return r; | |
296 | ||
74b2466e | 297 | *ret = s; |
74b2466e LP |
298 | s = NULL; |
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; | |
603 | n = saved_n; | |
604 | saved_n = NULL; | |
605 | } | |
606 | } | |
607 | } | |
608 | ||
eb241cdb LP |
609 | int dns_name_startswith(const char *name, const char *prefix) { |
610 | const char *n, *p; | |
611 | int r, q; | |
612 | ||
613 | assert(name); | |
614 | assert(prefix); | |
615 | ||
616 | n = name; | |
617 | p = prefix; | |
618 | ||
619 | for (;;) { | |
620 | char ln[DNS_LABEL_MAX], lp[DNS_LABEL_MAX]; | |
621 | ||
23b298bc | 622 | r = dns_label_unescape(&p, lp, sizeof(lp)); |
eb241cdb LP |
623 | if (r < 0) |
624 | return r; | |
625 | if (r == 0) | |
626 | return true; | |
627 | ||
23b298bc | 628 | q = dns_label_unescape(&n, ln, sizeof(ln)); |
eb241cdb LP |
629 | if (q < 0) |
630 | return q; | |
631 | ||
632 | if (r != q) | |
633 | return false; | |
634 | if (ascii_strcasecmp_n(ln, lp, r) != 0) | |
635 | return false; | |
636 | } | |
637 | } | |
638 | ||
58db254a LP |
639 | int dns_name_change_suffix(const char *name, const char *old_suffix, const char *new_suffix, char **ret) { |
640 | const char *n, *s, *saved_before = NULL, *saved_after = NULL, *prefix; | |
81ec9e08 | 641 | int r, q; |
58db254a LP |
642 | |
643 | assert(name); | |
644 | assert(old_suffix); | |
645 | assert(new_suffix); | |
646 | assert(ret); | |
647 | ||
648 | n = name; | |
649 | s = old_suffix; | |
650 | ||
651 | for (;;) { | |
3095011d | 652 | char ln[DNS_LABEL_MAX], ls[DNS_LABEL_MAX]; |
58db254a LP |
653 | |
654 | if (!saved_before) | |
655 | saved_before = n; | |
656 | ||
23b298bc | 657 | r = dns_label_unescape(&n, ln, sizeof(ln)); |
58db254a LP |
658 | if (r < 0) |
659 | return r; | |
58db254a LP |
660 | |
661 | if (!saved_after) | |
662 | saved_after = n; | |
663 | ||
23b298bc | 664 | q = dns_label_unescape(&s, ls, sizeof(ls)); |
58db254a LP |
665 | if (q < 0) |
666 | return q; | |
58db254a LP |
667 | |
668 | if (r == 0 && q == 0) | |
669 | break; | |
670 | if (r == 0 && saved_after == n) { | |
671 | *ret = NULL; /* doesn't match */ | |
672 | return 0; | |
673 | } | |
674 | ||
3095011d | 675 | if (r != q || ascii_strcasecmp_n(ln, ls, r) != 0) { |
58db254a LP |
676 | |
677 | /* Not the same, let's jump back, and try with the next label again */ | |
678 | s = old_suffix; | |
679 | n = saved_after; | |
680 | saved_after = saved_before = NULL; | |
681 | } | |
682 | } | |
683 | ||
684 | /* Found it! Now generate the new name */ | |
685 | prefix = strndupa(name, saved_before - name); | |
686 | ||
687 | r = dns_name_concat(prefix, new_suffix, ret); | |
688 | if (r < 0) | |
689 | return r; | |
690 | ||
691 | return 1; | |
692 | } | |
693 | ||
ae72b22c TG |
694 | int dns_name_between(const char *a, const char *b, const char *c) { |
695 | int n; | |
696 | ||
697 | /* Determine if b is strictly greater than a and strictly smaller than c. | |
698 | We consider the order of names to be circular, so that if a is | |
699 | strictly greater than c, we consider b to be between them if it is | |
700 | either greater than a or smaller than c. This is how the canonical | |
701 | DNS name order used in NSEC records work. */ | |
702 | ||
703 | n = dns_name_compare_func(a, c); | |
704 | if (n == 0) | |
705 | return -EINVAL; | |
706 | else if (n < 0) | |
707 | /* a<---b--->c */ | |
708 | return dns_name_compare_func(a, b) < 0 && | |
709 | dns_name_compare_func(b, c) < 0; | |
710 | else | |
711 | /* <--b--c a--b--> */ | |
712 | return dns_name_compare_func(b, c) < 0 || | |
713 | dns_name_compare_func(a, b) < 0; | |
714 | } | |
715 | ||
74b2466e LP |
716 | int dns_name_reverse(int family, const union in_addr_union *a, char **ret) { |
717 | const uint8_t *p; | |
718 | int r; | |
719 | ||
720 | assert(a); | |
721 | assert(ret); | |
722 | ||
723 | p = (const uint8_t*) a; | |
724 | ||
725 | if (family == AF_INET) | |
726 | r = asprintf(ret, "%u.%u.%u.%u.in-addr.arpa", p[3], p[2], p[1], p[0]); | |
727 | else if (family == AF_INET6) | |
3fe1169f LP |
728 | 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", |
729 | hexchar(p[15] & 0xF), hexchar(p[15] >> 4), hexchar(p[14] & 0xF), hexchar(p[14] >> 4), | |
730 | hexchar(p[13] & 0xF), hexchar(p[13] >> 4), hexchar(p[12] & 0xF), hexchar(p[12] >> 4), | |
731 | hexchar(p[11] & 0xF), hexchar(p[11] >> 4), hexchar(p[10] & 0xF), hexchar(p[10] >> 4), | |
732 | hexchar(p[ 9] & 0xF), hexchar(p[ 9] >> 4), hexchar(p[ 8] & 0xF), hexchar(p[ 8] >> 4), | |
733 | hexchar(p[ 7] & 0xF), hexchar(p[ 7] >> 4), hexchar(p[ 6] & 0xF), hexchar(p[ 6] >> 4), | |
734 | hexchar(p[ 5] & 0xF), hexchar(p[ 5] >> 4), hexchar(p[ 4] & 0xF), hexchar(p[ 4] >> 4), | |
735 | hexchar(p[ 3] & 0xF), hexchar(p[ 3] >> 4), hexchar(p[ 2] & 0xF), hexchar(p[ 2] >> 4), | |
736 | hexchar(p[ 1] & 0xF), hexchar(p[ 1] >> 4), hexchar(p[ 0] & 0xF), hexchar(p[ 0] >> 4)); | |
74b2466e LP |
737 | else |
738 | return -EAFNOSUPPORT; | |
739 | if (r < 0) | |
740 | return -ENOMEM; | |
741 | ||
742 | return 0; | |
743 | } | |
744 | ||
b914e211 LP |
745 | int dns_name_address(const char *p, int *family, union in_addr_union *address) { |
746 | int r; | |
747 | ||
748 | assert(p); | |
749 | assert(family); | |
750 | assert(address); | |
751 | ||
752 | r = dns_name_endswith(p, "in-addr.arpa"); | |
753 | if (r < 0) | |
754 | return r; | |
755 | if (r > 0) { | |
756 | uint8_t a[4]; | |
757 | unsigned i; | |
758 | ||
759 | for (i = 0; i < ELEMENTSOF(a); i++) { | |
760 | char label[DNS_LABEL_MAX+1]; | |
761 | ||
762 | r = dns_label_unescape(&p, label, sizeof(label)); | |
763 | if (r < 0) | |
764 | return r; | |
765 | if (r == 0) | |
766 | return -EINVAL; | |
767 | if (r > 3) | |
768 | return -EINVAL; | |
769 | ||
770 | r = safe_atou8(label, &a[i]); | |
771 | if (r < 0) | |
772 | return r; | |
773 | } | |
774 | ||
775 | r = dns_name_equal(p, "in-addr.arpa"); | |
776 | if (r <= 0) | |
777 | return r; | |
778 | ||
779 | *family = AF_INET; | |
780 | address->in.s_addr = htobe32(((uint32_t) a[3] << 24) | | |
781 | ((uint32_t) a[2] << 16) | | |
782 | ((uint32_t) a[1] << 8) | | |
783 | (uint32_t) a[0]); | |
784 | ||
785 | return 1; | |
786 | } | |
787 | ||
788 | r = dns_name_endswith(p, "ip6.arpa"); | |
789 | if (r < 0) | |
790 | return r; | |
791 | if (r > 0) { | |
792 | struct in6_addr a; | |
793 | unsigned i; | |
794 | ||
795 | for (i = 0; i < ELEMENTSOF(a.s6_addr); i++) { | |
796 | char label[DNS_LABEL_MAX+1]; | |
797 | int x, y; | |
798 | ||
799 | r = dns_label_unescape(&p, label, sizeof(label)); | |
800 | if (r <= 0) | |
801 | return r; | |
802 | if (r != 1) | |
803 | return -EINVAL; | |
804 | x = unhexchar(label[0]); | |
805 | if (x < 0) | |
806 | return -EINVAL; | |
807 | ||
808 | r = dns_label_unescape(&p, label, sizeof(label)); | |
809 | if (r <= 0) | |
810 | return r; | |
811 | if (r != 1) | |
812 | return -EINVAL; | |
813 | y = unhexchar(label[0]); | |
814 | if (y < 0) | |
815 | return -EINVAL; | |
816 | ||
817 | a.s6_addr[ELEMENTSOF(a.s6_addr) - i - 1] = (uint8_t) y << 4 | (uint8_t) x; | |
818 | } | |
819 | ||
820 | r = dns_name_equal(p, "ip6.arpa"); | |
821 | if (r <= 0) | |
822 | return r; | |
823 | ||
824 | *family = AF_INET6; | |
825 | address->in6 = a; | |
826 | return 1; | |
827 | } | |
828 | ||
829 | return 0; | |
830 | } | |
831 | ||
dc477e73 | 832 | bool dns_name_is_root(const char *name) { |
74b2466e LP |
833 | |
834 | assert(name); | |
835 | ||
dc477e73 LP |
836 | /* There are exactly two ways to encode the root domain name: |
837 | * as empty string, or with a single dot. */ | |
74b2466e | 838 | |
dc477e73 | 839 | return STR_IN_SET(name, "", "."); |
74b2466e LP |
840 | } |
841 | ||
dc477e73 | 842 | bool dns_name_is_single_label(const char *name) { |
74b2466e LP |
843 | int r; |
844 | ||
845 | assert(name); | |
846 | ||
f6fbd9c2 | 847 | r = dns_name_parent(&name); |
dc477e73 LP |
848 | if (r <= 0) |
849 | return false; | |
74b2466e | 850 | |
dc477e73 | 851 | return dns_name_is_root(name); |
74b2466e | 852 | } |
54adabf7 | 853 | |
50dee79b | 854 | /* Encode a domain name according to RFC 1035 Section 3.1, without compression */ |
3cd03457 | 855 | int dns_name_to_wire_format(const char *domain, uint8_t *buffer, size_t len, bool canonical) { |
c6cefd13 | 856 | uint8_t *label_length, *out; |
54adabf7 BG |
857 | int r; |
858 | ||
c6cefd13 LP |
859 | assert(domain); |
860 | assert(buffer); | |
54adabf7 BG |
861 | |
862 | out = buffer; | |
863 | ||
864 | do { | |
50dee79b | 865 | /* Reserve a byte for label length */ |
c6cefd13 | 866 | if (len <= 0) |
54adabf7 BG |
867 | return -ENOBUFS; |
868 | len--; | |
869 | label_length = out; | |
870 | out++; | |
871 | ||
50dee79b LP |
872 | /* Convert and copy a single label. Note that |
873 | * dns_label_unescape() returns 0 when it hits the end | |
874 | * of the domain name, which we rely on here to encode | |
875 | * the trailing NUL byte. */ | |
54adabf7 BG |
876 | r = dns_label_unescape(&domain, (char *) out, len); |
877 | if (r < 0) | |
878 | return r; | |
879 | ||
b577e3d5 LP |
880 | /* Optionally, output the name in DNSSEC canonical |
881 | * format, as described in RFC 4034, section 6.2. Or | |
882 | * in other words: in lower-case. */ | |
883 | if (canonical) | |
884 | ascii_strlower_n((char*) out, (size_t) r); | |
3cd03457 | 885 | |
50dee79b | 886 | /* Fill label length, move forward */ |
54adabf7 BG |
887 | *label_length = r; |
888 | out += r; | |
889 | len -= r; | |
50dee79b | 890 | |
54adabf7 BG |
891 | } while (r != 0); |
892 | ||
50dee79b LP |
893 | /* Verify the maximum size of the encoded name. The trailing |
894 | * dot + NUL byte account are included this time, hence | |
895 | * compare against DNS_HOSTNAME_MAX + 2 (which is 255) this | |
896 | * time. */ | |
897 | if (out - buffer > DNS_HOSTNAME_MAX + 2) | |
898 | return -EINVAL; | |
899 | ||
54adabf7 BG |
900 | return out - buffer; |
901 | } | |
0a49b6b6 | 902 | |
0e8eedbb LP |
903 | static bool srv_type_label_is_valid(const char *label, size_t n) { |
904 | size_t k; | |
905 | ||
906 | assert(label); | |
907 | ||
908 | if (n < 2) /* Label needs to be at least 2 chars long */ | |
909 | return false; | |
910 | ||
911 | if (label[0] != '_') /* First label char needs to be underscore */ | |
912 | return false; | |
913 | ||
914 | /* Second char must be a letter */ | |
915 | if (!(label[1] >= 'A' && label[1] <= 'Z') && | |
916 | !(label[1] >= 'a' && label[1] <= 'z')) | |
917 | return false; | |
918 | ||
919 | /* Third and further chars must be alphanumeric or a hyphen */ | |
920 | for (k = 2; k < n; k++) { | |
921 | if (!(label[k] >= 'A' && label[k] <= 'Z') && | |
922 | !(label[k] >= 'a' && label[k] <= 'z') && | |
923 | !(label[k] >= '0' && label[k] <= '9') && | |
924 | label[k] != '-') | |
925 | return false; | |
926 | } | |
927 | ||
928 | return true; | |
929 | } | |
930 | ||
7e8131e9 | 931 | bool dns_srv_type_is_valid(const char *name) { |
0a49b6b6 LP |
932 | unsigned c = 0; |
933 | int r; | |
934 | ||
935 | if (!name) | |
7e8131e9 | 936 | return false; |
0a49b6b6 LP |
937 | |
938 | for (;;) { | |
939 | char label[DNS_LABEL_MAX]; | |
0a49b6b6 LP |
940 | |
941 | /* This more or less implements RFC 6335, Section 5.1 */ | |
942 | ||
943 | r = dns_label_unescape(&name, label, sizeof(label)); | |
0a49b6b6 | 944 | if (r < 0) |
7e8131e9 | 945 | return false; |
0a49b6b6 | 946 | if (r == 0) |
0e8eedbb | 947 | break; |
0a49b6b6 | 948 | |
0e8eedbb | 949 | if (c >= 2) |
7e8131e9 | 950 | return false; |
0a49b6b6 | 951 | |
0e8eedbb | 952 | if (!srv_type_label_is_valid(label, r)) |
7e8131e9 | 953 | return false; |
0a49b6b6 LP |
954 | |
955 | c++; | |
956 | } | |
0e8eedbb LP |
957 | |
958 | return c == 2; /* exactly two labels */ | |
0a49b6b6 LP |
959 | } |
960 | ||
961 | bool dns_service_name_is_valid(const char *name) { | |
962 | size_t l; | |
963 | ||
964 | /* This more or less implements RFC 6763, Section 4.1.1 */ | |
965 | ||
966 | if (!name) | |
967 | return false; | |
968 | ||
969 | if (!utf8_is_valid(name)) | |
970 | return false; | |
971 | ||
972 | if (string_has_cc(name, NULL)) | |
973 | return false; | |
974 | ||
975 | l = strlen(name); | |
976 | if (l <= 0) | |
977 | return false; | |
978 | if (l > 63) | |
979 | return false; | |
980 | ||
981 | return true; | |
982 | } | |
0e8eedbb LP |
983 | |
984 | int dns_service_join(const char *name, const char *type, const char *domain, char **ret) { | |
422baca0 LP |
985 | char escaped[DNS_LABEL_ESCAPED_MAX]; |
986 | _cleanup_free_ char *n = NULL; | |
0e8eedbb LP |
987 | int r; |
988 | ||
989 | assert(type); | |
990 | assert(domain); | |
991 | assert(ret); | |
992 | ||
7e8131e9 | 993 | if (!dns_srv_type_is_valid(type)) |
0e8eedbb LP |
994 | return -EINVAL; |
995 | ||
996 | if (!name) | |
997 | return dns_name_concat(type, domain, ret); | |
998 | ||
999 | if (!dns_service_name_is_valid(name)) | |
1000 | return -EINVAL; | |
1001 | ||
422baca0 | 1002 | r = dns_label_escape(name, strlen(name), escaped, sizeof(escaped)); |
0e8eedbb LP |
1003 | if (r < 0) |
1004 | return r; | |
1005 | ||
1006 | r = dns_name_concat(type, domain, &n); | |
1007 | if (r < 0) | |
1008 | return r; | |
1009 | ||
1010 | return dns_name_concat(escaped, n, ret); | |
1011 | } | |
1012 | ||
1013 | static bool dns_service_name_label_is_valid(const char *label, size_t n) { | |
1014 | char *s; | |
1015 | ||
1016 | assert(label); | |
1017 | ||
1018 | if (memchr(label, 0, n)) | |
1019 | return false; | |
1020 | ||
1021 | s = strndupa(label, n); | |
1022 | return dns_service_name_is_valid(s); | |
1023 | } | |
1024 | ||
1025 | int dns_service_split(const char *joined, char **_name, char **_type, char **_domain) { | |
1026 | _cleanup_free_ char *name = NULL, *type = NULL, *domain = NULL; | |
1027 | const char *p = joined, *q = NULL, *d = NULL; | |
1028 | char a[DNS_LABEL_MAX], b[DNS_LABEL_MAX], c[DNS_LABEL_MAX]; | |
1029 | int an, bn, cn, r; | |
1030 | unsigned x = 0; | |
1031 | ||
1032 | assert(joined); | |
1033 | ||
1034 | /* Get first label from the full name */ | |
1035 | an = dns_label_unescape(&p, a, sizeof(a)); | |
1036 | if (an < 0) | |
1037 | return an; | |
1038 | ||
1039 | if (an > 0) { | |
1040 | x++; | |
1041 | ||
1042 | /* If there was a first label, try to get the second one */ | |
1043 | bn = dns_label_unescape(&p, b, sizeof(b)); | |
1044 | if (bn < 0) | |
1045 | return bn; | |
1046 | ||
1047 | if (bn > 0) { | |
1048 | x++; | |
1049 | ||
1050 | /* If there was a second label, try to get the third one */ | |
1051 | q = p; | |
1052 | cn = dns_label_unescape(&p, c, sizeof(c)); | |
1053 | if (cn < 0) | |
1054 | return cn; | |
1055 | ||
1056 | if (cn > 0) | |
1057 | x++; | |
1058 | } else | |
1059 | cn = 0; | |
1060 | } else | |
1061 | an = 0; | |
1062 | ||
1063 | if (x >= 2 && srv_type_label_is_valid(b, bn)) { | |
1064 | ||
1065 | if (x >= 3 && srv_type_label_is_valid(c, cn)) { | |
1066 | ||
1067 | if (dns_service_name_label_is_valid(a, an)) { | |
0e8eedbb LP |
1068 | /* OK, got <name> . <type> . <type2> . <domain> */ |
1069 | ||
1070 | name = strndup(a, an); | |
1071 | if (!name) | |
1072 | return -ENOMEM; | |
1073 | ||
605405c6 | 1074 | type = strjoin(b, ".", c); |
0e8eedbb LP |
1075 | if (!type) |
1076 | return -ENOMEM; | |
0e8eedbb LP |
1077 | |
1078 | d = p; | |
1079 | goto finish; | |
1080 | } | |
1081 | ||
1082 | } else if (srv_type_label_is_valid(a, an)) { | |
1083 | ||
1084 | /* OK, got <type> . <type2> . <domain> */ | |
1085 | ||
1086 | name = NULL; | |
1087 | ||
605405c6 | 1088 | type = strjoin(a, ".", b); |
0e8eedbb LP |
1089 | if (!type) |
1090 | return -ENOMEM; | |
0e8eedbb LP |
1091 | |
1092 | d = q; | |
1093 | goto finish; | |
1094 | } | |
1095 | } | |
1096 | ||
1097 | name = NULL; | |
1098 | type = NULL; | |
1099 | d = joined; | |
1100 | ||
1101 | finish: | |
1102 | r = dns_name_normalize(d, &domain); | |
1103 | if (r < 0) | |
1104 | return r; | |
1105 | ||
1106 | if (_domain) { | |
1107 | *_domain = domain; | |
1108 | domain = NULL; | |
1109 | } | |
1110 | ||
1111 | if (_type) { | |
1112 | *_type = type; | |
1113 | type = NULL; | |
1114 | } | |
1115 | ||
1116 | if (_name) { | |
1117 | *_name = name; | |
1118 | name = NULL; | |
1119 | } | |
1120 | ||
1121 | return 0; | |
1122 | } | |
e7ff0e0b | 1123 | |
b9282bc1 | 1124 | static int dns_name_build_suffix_table(const char *name, const char*table[]) { |
e7ff0e0b | 1125 | const char *p; |
b9282bc1 | 1126 | unsigned n = 0; |
e7ff0e0b LP |
1127 | int r; |
1128 | ||
1129 | assert(name); | |
b9282bc1 | 1130 | assert(table); |
e7ff0e0b LP |
1131 | |
1132 | p = name; | |
1133 | for (;;) { | |
1134 | if (n > DNS_N_LABELS_MAX) | |
1135 | return -EINVAL; | |
1136 | ||
b9282bc1 | 1137 | table[n] = p; |
e7ff0e0b LP |
1138 | r = dns_name_parent(&p); |
1139 | if (r < 0) | |
1140 | return r; | |
1141 | if (r == 0) | |
1142 | break; | |
1143 | ||
1144 | n++; | |
1145 | } | |
1146 | ||
b9282bc1 LP |
1147 | return (int) n; |
1148 | } | |
1149 | ||
1150 | int dns_name_suffix(const char *name, unsigned n_labels, const char **ret) { | |
1151 | const char* labels[DNS_N_LABELS_MAX+1]; | |
1152 | int n; | |
1153 | ||
1154 | assert(name); | |
1155 | assert(ret); | |
1156 | ||
1157 | n = dns_name_build_suffix_table(name, labels); | |
1158 | if (n < 0) | |
1159 | return n; | |
1160 | ||
1161 | if ((unsigned) n < n_labels) | |
e7ff0e0b LP |
1162 | return -EINVAL; |
1163 | ||
1164 | *ret = labels[n - n_labels]; | |
1165 | return (int) (n - n_labels); | |
1166 | } | |
1167 | ||
97c67192 LP |
1168 | int dns_name_skip(const char *a, unsigned n_labels, const char **ret) { |
1169 | int r; | |
1170 | ||
1171 | assert(a); | |
1172 | assert(ret); | |
1173 | ||
313cefa1 | 1174 | for (; n_labels > 0; n_labels--) { |
97c67192 LP |
1175 | r = dns_name_parent(&a); |
1176 | if (r < 0) | |
1177 | return r; | |
1178 | if (r == 0) { | |
1179 | *ret = ""; | |
1180 | return 0; | |
1181 | } | |
1182 | } | |
1183 | ||
1184 | *ret = a; | |
1185 | return 1; | |
1186 | } | |
1187 | ||
e7ff0e0b LP |
1188 | int dns_name_count_labels(const char *name) { |
1189 | unsigned n = 0; | |
1190 | const char *p; | |
1191 | int r; | |
1192 | ||
1193 | assert(name); | |
1194 | ||
1195 | p = name; | |
1196 | for (;;) { | |
1197 | r = dns_name_parent(&p); | |
1198 | if (r < 0) | |
1199 | return r; | |
1200 | if (r == 0) | |
1201 | break; | |
1202 | ||
1203 | if (n >= DNS_N_LABELS_MAX) | |
1204 | return -EINVAL; | |
1205 | ||
1206 | n++; | |
1207 | } | |
1208 | ||
1209 | return (int) n; | |
1210 | } | |
db5b0e92 LP |
1211 | |
1212 | int dns_name_equal_skip(const char *a, unsigned n_labels, const char *b) { | |
1213 | int r; | |
1214 | ||
1215 | assert(a); | |
1216 | assert(b); | |
1217 | ||
97c67192 LP |
1218 | r = dns_name_skip(a, n_labels, &a); |
1219 | if (r <= 0) | |
1220 | return r; | |
db5b0e92 LP |
1221 | |
1222 | return dns_name_equal(a, b); | |
1223 | } | |
b9282bc1 LP |
1224 | |
1225 | int dns_name_common_suffix(const char *a, const char *b, const char **ret) { | |
1226 | const char *a_labels[DNS_N_LABELS_MAX+1], *b_labels[DNS_N_LABELS_MAX+1]; | |
1227 | int n = 0, m = 0, k = 0, r, q; | |
1228 | ||
1229 | assert(a); | |
1230 | assert(b); | |
1231 | assert(ret); | |
1232 | ||
1233 | /* Determines the common suffix of domain names a and b */ | |
1234 | ||
1235 | n = dns_name_build_suffix_table(a, a_labels); | |
1236 | if (n < 0) | |
1237 | return n; | |
1238 | ||
1239 | m = dns_name_build_suffix_table(b, b_labels); | |
1240 | if (m < 0) | |
1241 | return m; | |
1242 | ||
1243 | for (;;) { | |
1244 | char la[DNS_LABEL_MAX], lb[DNS_LABEL_MAX]; | |
1245 | const char *x, *y; | |
1246 | ||
1247 | if (k >= n || k >= m) { | |
1248 | *ret = a_labels[n - k]; | |
1249 | return 0; | |
1250 | } | |
1251 | ||
1252 | x = a_labels[n - 1 - k]; | |
23b298bc | 1253 | r = dns_label_unescape(&x, la, sizeof(la)); |
b9282bc1 LP |
1254 | if (r < 0) |
1255 | return r; | |
1256 | ||
1257 | y = b_labels[m - 1 - k]; | |
23b298bc | 1258 | q = dns_label_unescape(&y, lb, sizeof(lb)); |
b9282bc1 LP |
1259 | if (q < 0) |
1260 | return q; | |
1261 | ||
1262 | if (r != q || ascii_strcasecmp_n(la, lb, r) != 0) { | |
1263 | *ret = a_labels[n - k]; | |
1264 | return 0; | |
1265 | } | |
1266 | ||
1267 | k++; | |
1268 | } | |
1269 | } | |
0cf40f55 LP |
1270 | |
1271 | int dns_name_apply_idna(const char *name, char **ret) { | |
87057e24 ZJS |
1272 | /* Return negative on error, 0 if not implemented, positive on success. */ |
1273 | ||
349cc4a5 | 1274 | #if HAVE_LIBIDN2 |
87057e24 | 1275 | int r; |
0926f348 | 1276 | _cleanup_free_ char *t = NULL; |
87057e24 ZJS |
1277 | |
1278 | assert(name); | |
1279 | assert(ret); | |
1280 | ||
0926f348 | 1281 | r = idn2_lookup_u8((uint8_t*) name, (uint8_t**) &t, |
87057e24 | 1282 | IDN2_NFC_INPUT | IDN2_NONTRANSITIONAL); |
0926f348 ZJS |
1283 | log_debug("idn2_lookup_u8: %s → %s", name, t); |
1284 | if (r == IDN2_OK) { | |
1285 | if (!startswith(name, "xn--")) { | |
1286 | _cleanup_free_ char *s = NULL; | |
1287 | ||
1288 | r = idn2_to_unicode_8z8z(t, &s, 0); | |
1289 | if (r != IDN2_OK) { | |
1290 | log_debug("idn2_to_unicode_8z8z(\"%s\") failed: %d/%s", | |
1291 | t, r, idn2_strerror(r)); | |
1292 | return 0; | |
1293 | } | |
1294 | ||
1295 | if (!streq_ptr(name, s)) { | |
1296 | log_debug("idn2 roundtrip failed: \"%s\" → \"%s\" → \"%s\", ignoring.", | |
1297 | name, t, s); | |
1298 | return 0; | |
1299 | } | |
1300 | } | |
1301 | ||
1302 | *ret = t; | |
1303 | t = NULL; | |
87057e24 | 1304 | return 1; /* *ret has been written */ |
0926f348 ZJS |
1305 | } |
1306 | ||
1307 | log_debug("idn2_lookup_u8(\"%s\") failed: %d/%s", name, r, idn2_strerror(r)); | |
ad1f3fe6 ZJS |
1308 | if (r == IDN2_2HYPHEN) |
1309 | /* The name has two hypens — forbidden by IDNA2008 in some cases */ | |
1310 | return 0; | |
1311 | if (IN_SET(r, IDN2_TOO_BIG_DOMAIN, IDN2_TOO_BIG_LABEL)) | |
87057e24 | 1312 | return -ENOSPC; |
ad1f3fe6 | 1313 | return -EINVAL; |
349cc4a5 | 1314 | #elif HAVE_LIBIDN |
0cf40f55 LP |
1315 | _cleanup_free_ char *buf = NULL; |
1316 | size_t n = 0, allocated = 0; | |
1317 | bool first = true; | |
1318 | int r, q; | |
1319 | ||
1320 | assert(name); | |
1321 | assert(ret); | |
1322 | ||
1323 | for (;;) { | |
1324 | char label[DNS_LABEL_MAX]; | |
1325 | ||
1326 | r = dns_label_unescape(&name, label, sizeof(label)); | |
1327 | if (r < 0) | |
1328 | return r; | |
1329 | if (r == 0) | |
1330 | break; | |
1331 | ||
1332 | q = dns_label_apply_idna(label, r, label, sizeof(label)); | |
1333 | if (q < 0) | |
1334 | return q; | |
1335 | if (q > 0) | |
1336 | r = q; | |
1337 | ||
1338 | if (!GREEDY_REALLOC(buf, allocated, n + !first + DNS_LABEL_ESCAPED_MAX)) | |
1339 | return -ENOMEM; | |
1340 | ||
1341 | r = dns_label_escape(label, r, buf + n + !first, DNS_LABEL_ESCAPED_MAX); | |
1342 | if (r < 0) | |
1343 | return r; | |
1344 | ||
1345 | if (first) | |
1346 | first = false; | |
1347 | else | |
1348 | buf[n++] = '.'; | |
1349 | ||
ad1f3fe6 | 1350 | n += r; |
0cf40f55 LP |
1351 | } |
1352 | ||
1353 | if (n > DNS_HOSTNAME_MAX) | |
1354 | return -EINVAL; | |
1355 | ||
1356 | if (!GREEDY_REALLOC(buf, allocated, n + 1)) | |
1357 | return -ENOMEM; | |
1358 | ||
1359 | buf[n] = 0; | |
1360 | *ret = buf; | |
1361 | buf = NULL; | |
1362 | ||
ad1f3fe6 | 1363 | return 1; |
87057e24 ZJS |
1364 | #else |
1365 | return 0; | |
1366 | #endif | |
0cf40f55 | 1367 | } |
08a4849e LP |
1368 | |
1369 | int dns_name_is_valid_or_address(const char *name) { | |
1370 | /* Returns > 0 if the specified name is either a valid IP address formatted as string or a valid DNS name */ | |
1371 | ||
1372 | if (isempty(name)) | |
1373 | return 0; | |
1374 | ||
1375 | if (in_addr_from_string_auto(name, NULL, NULL) >= 0) | |
1376 | return 1; | |
1377 | ||
1378 | return dns_name_is_valid(name); | |
1379 | } |