Coverage Report

Created: 2024-06-25 06:24

/src/avahi/avahi-common/domain.c
Line
Count
Source (jump to first uncovered line)
1
/***
2
  This file is part of avahi.
3
4
  avahi is free software; you can redistribute it and/or modify it
5
  under the terms of the GNU Lesser General Public License as
6
  published by the Free Software Foundation; either version 2.1 of the
7
  License, or (at your option) any later version.
8
9
  avahi is distributed in the hope that it will be useful, but WITHOUT
10
  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
11
  or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General
12
  Public License for more details.
13
14
  You should have received a copy of the GNU Lesser General Public
15
  License along with avahi; if not, write to the Free Software
16
  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
17
  USA.
18
***/
19
20
#ifdef HAVE_CONFIG_H
21
#include <config.h>
22
#endif
23
24
#include <string.h>
25
#include <unistd.h>
26
#include <fcntl.h>
27
#include <errno.h>
28
#include <limits.h>
29
#include <stdio.h>
30
#include <ctype.h>
31
#include <stdlib.h>
32
#include <assert.h>
33
34
#include "domain.h"
35
#include "malloc.h"
36
#include "error.h"
37
#include "address.h"
38
#include "utf8.h"
39
40
/* Read the first label from string *name, unescape "\" and write it to dest */
41
1.64M
char *avahi_unescape_label(const char **name, char *dest, size_t size) {
42
1.64M
    unsigned i = 0;
43
1.64M
    char *d;
44
45
1.64M
    assert(dest);
46
1.64M
    assert(size > 0);
47
1.64M
    assert(name);
48
49
1.64M
    d = dest;
50
51
10.4M
    for (;;) {
52
10.4M
        if (i >= size)
53
61
            return NULL;
54
55
10.4M
        if (**name == '.') {
56
1.25M
            (*name)++;
57
1.25M
            break;
58
1.25M
        }
59
60
9.17M
        if (**name == 0)
61
392k
            break;
62
63
8.78M
        if (**name == '\\') {
64
            /* Escaped character */
65
66
4.05M
            (*name) ++;
67
68
4.05M
            if (**name == 0)
69
                /* Ending NUL */
70
71
                return NULL;
71
72
4.05M
            else if (**name == '\\' || **name == '.') {
73
                /* Escaped backslash or dot */
74
431k
                *(d++) = *((*name) ++);
75
431k
                i++;
76
3.62M
            } else if (isdigit(**name)) {
77
3.62M
                int n;
78
79
                /* Escaped literal ASCII character */
80
81
3.62M
                if (!isdigit(*(*name+1)) || !isdigit(*(*name+2)))
82
42
                    return NULL;
83
84
3.62M
                n = ((uint8_t) (**name - '0') * 100) + ((uint8_t) (*(*name+1) - '0') * 10) + ((uint8_t) (*(*name +2) - '0'));
85
86
3.62M
                if (n > 255 || n == 0)
87
128
                    return NULL;
88
89
3.62M
                *(d++) = (char) n;
90
3.62M
                i++;
91
92
3.62M
                (*name) += 3;
93
3.62M
            } else
94
253
                return NULL;
95
96
4.72M
        } else {
97
98
            /* Normal character */
99
100
4.72M
            *(d++) = *((*name) ++);
101
4.72M
            i++;
102
4.72M
        }
103
8.78M
    }
104
105
1.64M
    assert(i < size);
106
107
1.64M
    *d = 0;
108
109
1.64M
    if (!avahi_utf8_valid(dest))
110
872
        return NULL;
111
112
1.64M
    return dest;
113
1.64M
}
114
115
/* Escape "\" and ".", append \0 */
116
336k
char *avahi_escape_label(const char* src, size_t src_length, char **ret_name, size_t *ret_size) {
117
336k
    char *r;
118
119
336k
    assert(src);
120
336k
    assert(ret_name);
121
336k
    assert(*ret_name);
122
336k
    assert(ret_size);
123
336k
    assert(*ret_size > 0);
124
125
336k
    r = *ret_name;
126
127
2.67M
    while (src_length > 0) {
128
2.33M
        if (*src == '.' || *src == '\\') {
129
130
            /* Dot or backslash */
131
132
107k
            if (*ret_size < 3)
133
13
                return NULL;
134
135
107k
            *((*ret_name) ++) = '\\';
136
107k
            *((*ret_name) ++) = *src;
137
107k
            (*ret_size) -= 2;
138
139
2.23M
        } else if (
140
2.23M
            *src == '_' ||
141
2.23M
            *src == '-' ||
142
2.23M
            (*src >= '0' && *src <= '9') ||
143
2.23M
            (*src >= 'a' && *src <= 'z') ||
144
2.23M
            (*src >= 'A' && *src <= 'Z')) {
145
146
            /* Proper character */
147
148
1.28M
            if (*ret_size < 2)
149
16
                return NULL;
150
151
1.28M
            *((*ret_name)++) = *src;
152
1.28M
            (*ret_size) --;
153
154
1.28M
        } else {
155
156
            /* Everything else */
157
158
948k
            if (*ret_size < 5)
159
53
                return NULL;
160
161
948k
            *((*ret_name) ++) = '\\';
162
948k
            *((*ret_name) ++) = '0' + (char)  ((uint8_t) *src / 100);
163
948k
            *((*ret_name) ++) = '0' + (char) (((uint8_t) *src / 10) % 10);
164
948k
            *((*ret_name) ++) = '0' + (char)  ((uint8_t) *src % 10);
165
166
948k
            (*ret_size) -= 4;
167
948k
        }
168
169
2.33M
        src_length --;
170
2.33M
        src++;
171
2.33M
    }
172
173
336k
    **ret_name = 0;
174
175
336k
    return r;
176
336k
}
177
178
165k
char *avahi_normalize_name(const char *s, char *ret_s, size_t size) {
179
165k
    int empty = 1;
180
165k
    char *r;
181
182
165k
    assert(s);
183
165k
    assert(ret_s);
184
165k
    assert(size > 0);
185
186
165k
    r = ret_s;
187
165k
    *ret_s = 0;
188
189
313k
    while (*s) {
190
148k
        char label[AVAHI_LABEL_MAX];
191
192
148k
        if (!(avahi_unescape_label(&s, label, sizeof(label))))
193
389
            return NULL;
194
195
147k
        if (label[0] == 0) {
196
197
22
            if (*s == 0 && empty)
198
1
                return ret_s;
199
200
21
            return NULL;
201
22
        }
202
203
147k
        if (!empty) {
204
133k
            if (size < 2)
205
3
                return NULL;
206
207
133k
            *(r++) = '.';
208
133k
            size--;
209
210
133k
        } else
211
14.5k
            empty = 0;
212
213
147k
        if (!(avahi_escape_label(label, strlen(label), &r, &size)))
214
31
            return NULL;
215
147k
    }
216
217
164k
    return ret_s;
218
165k
}
219
220
162k
char *avahi_normalize_name_strdup(const char *s) {
221
162k
    char t[AVAHI_DOMAIN_NAME_MAX];
222
162k
    assert(s);
223
224
162k
    if (!(avahi_normalize_name(s, t, sizeof(t))))
225
434
        return NULL;
226
227
161k
    return avahi_strdup(t);
228
162k
}
229
230
324k
int avahi_domain_equal(const char *a, const char *b) {
231
324k
    assert(a);
232
324k
    assert(b);
233
234
324k
    if (a == b)
235
0
        return 1;
236
237
343k
    for (;;) {
238
343k
        char ca[AVAHI_LABEL_MAX], cb[AVAHI_LABEL_MAX], *r;
239
240
343k
        r = avahi_unescape_label(&a, ca, sizeof(ca));
241
343k
        assert(r);
242
343k
        r = avahi_unescape_label(&b, cb, sizeof(cb));
243
343k
        assert(r);
244
245
343k
        if (strcasecmp(ca, cb))
246
318k
            return 0;
247
248
24.6k
        if (!*a && !*b)
249
5.44k
            return 1;
250
24.6k
    }
251
252
0
    return 1;
253
324k
}
254
255
2.26k
int avahi_is_valid_service_type_generic(const char *t) {
256
2.26k
    assert(t);
257
258
2.26k
    if (strlen(t) >= AVAHI_DOMAIN_NAME_MAX || !*t)
259
44
        return 0;
260
261
5.32k
    do {
262
5.32k
        char label[AVAHI_LABEL_MAX];
263
264
5.32k
        if (!(avahi_unescape_label(&t, label, sizeof(label))))
265
123
            return 0;
266
267
5.20k
        if (strlen(label) <= 2 || label[0] != '_')
268
665
            return 0;
269
270
5.20k
    } while (*t);
271
272
1.43k
    return 1;
273
2.22k
}
274
275
8.07k
int avahi_is_valid_service_type_strict(const char *t) {
276
8.07k
    char label[AVAHI_LABEL_MAX];
277
8.07k
    assert(t);
278
279
8.07k
    if (strlen(t) >= AVAHI_DOMAIN_NAME_MAX || !*t)
280
1.40k
        return 0;
281
282
    /* Application name */
283
284
6.67k
    if (!(avahi_unescape_label(&t, label, sizeof(label))))
285
101
        return 0;
286
287
6.56k
    if (strlen(label) <= 2 || label[0] != '_')
288
877
        return 0;
289
290
5.69k
    if (!*t)
291
1.19k
        return 0;
292
293
    /* _tcp or _udp boilerplate */
294
295
4.49k
    if (!(avahi_unescape_label(&t, label, sizeof(label))))
296
11
        return 0;
297
298
4.48k
    if (strcasecmp(label, "_tcp") && strcasecmp(label, "_udp"))
299
3.23k
        return 0;
300
301
1.25k
    if (*t)
302
365
        return 0;
303
304
885
    return 1;
305
1.25k
}
306
307
7.19k
const char *avahi_get_type_from_subtype(const char *t) {
308
7.19k
    char label[AVAHI_LABEL_MAX];
309
7.19k
    const char *ret;
310
7.19k
    assert(t);
311
312
7.19k
    if (strlen(t) >= AVAHI_DOMAIN_NAME_MAX || !*t)
313
1.40k
        return NULL;
314
315
    /* Subtype name */
316
317
5.78k
    if (!(avahi_unescape_label(&t, label, sizeof(label))))
318
101
        return NULL;
319
320
5.68k
    if (strlen(label) <= 2 || label[0] != '_')
321
877
        return NULL;
322
323
4.80k
    if (!*t)
324
1.19k
        return NULL;
325
326
    /* String "_sub" */
327
328
3.61k
    if (!(avahi_unescape_label(&t, label, sizeof(label))))
329
11
        return NULL;
330
331
3.60k
    if (strcasecmp(label, "_sub"))
332
1.62k
        return NULL;
333
334
1.97k
    if (!*t)
335
351
        return NULL;
336
337
1.62k
    ret = t;
338
339
    /* Application name */
340
341
1.62k
    if (!(avahi_unescape_label(&t, label, sizeof(label))))
342
3
        return NULL;
343
344
1.62k
    if (strlen(label) <= 2 || label[0] != '_')
345
246
        return NULL;
346
347
1.37k
    if (!*t)
348
213
        return NULL;
349
350
    /* _tcp or _udp boilerplate */
351
352
1.16k
    if (!(avahi_unescape_label(&t, label, sizeof(label))))
353
2
        return NULL;
354
355
1.16k
    if (strcasecmp(label, "_tcp") && strcasecmp(label, "_udp"))
356
316
        return NULL;
357
358
846
    if (*t)
359
394
        return NULL;
360
361
452
    return ret;
362
846
}
363
364
7.19k
int avahi_is_valid_service_subtype(const char *t) {
365
7.19k
    assert(t);
366
367
7.19k
    return !!avahi_get_type_from_subtype(t);
368
7.19k
}
369
370
177k
int avahi_is_valid_domain_name(const char *t) {
371
177k
    int is_first = 1;
372
177k
    assert(t);
373
374
177k
    if (strlen(t) >= AVAHI_DOMAIN_NAME_MAX)
375
42
        return 0;
376
377
346k
    do {
378
346k
        char label[AVAHI_LABEL_MAX];
379
380
346k
        if (!(avahi_unescape_label(&t, label, sizeof(label))))
381
484
            return 0;
382
383
        /* Explicitly allow the root domain name */
384
346k
        if (is_first && label[0] == 0 && *t == 0)
385
156k
            return 1;
386
387
190k
        is_first = 0;
388
389
190k
        if (label[0] == 0)
390
44
            return 0;
391
392
190k
    } while (*t);
393
394
20.7k
    return 1;
395
177k
}
396
397
6.94k
int avahi_is_valid_service_name(const char *t) {
398
6.94k
    assert(t);
399
400
6.94k
    if (strlen(t) >= AVAHI_LABEL_MAX || !*t || !avahi_utf8_valid(t))
401
1.06k
        return 0;
402
403
5.88k
    return 1;
404
6.94k
}
405
406
2.26k
int avahi_is_valid_host_name(const char *t) {
407
2.26k
    char label[AVAHI_LABEL_MAX];
408
2.26k
    assert(t);
409
410
2.26k
    if (strlen(t) >= AVAHI_DOMAIN_NAME_MAX || !*t)
411
88
        return 0;
412
413
2.17k
    if (!(avahi_unescape_label(&t, label, sizeof(label))))
414
202
        return 0;
415
416
1.97k
    if (strlen(label) < 1)
417
28
        return 0;
418
419
1.94k
    if (*t)
420
760
        return 0;
421
422
1.18k
    return 1;
423
1.94k
}
424
425
611
unsigned avahi_domain_hash(const char *s) {
426
611
    unsigned hash = 0;
427
428
10.6k
    while (*s) {
429
10.0k
        char c[AVAHI_LABEL_MAX], *p, *r;
430
431
10.0k
        r = avahi_unescape_label(&s, c, sizeof(c));
432
10.0k
        assert(r);
433
434
23.1k
        for (p = c; *p; p++)
435
13.1k
            hash = 31 * hash + tolower(*p);
436
10.0k
    }
437
438
611
    return hash;
439
611
}
440
441
1.33k
int avahi_service_name_join(char *p, size_t size, const char *name, const char *type, const char *domain) {
442
1.33k
    char escaped_name[AVAHI_LABEL_MAX*4];
443
1.33k
    char normalized_type[AVAHI_DOMAIN_NAME_MAX];
444
1.33k
    char normalized_domain[AVAHI_DOMAIN_NAME_MAX];
445
446
1.33k
    assert(p);
447
448
    /* Validity checks */
449
450
1.33k
    if ((name && !avahi_is_valid_service_name(name)))
451
0
        return AVAHI_ERR_INVALID_SERVICE_NAME;
452
453
1.33k
    if (!avahi_is_valid_service_type_generic(type))
454
0
        return AVAHI_ERR_INVALID_SERVICE_TYPE;
455
456
1.33k
    if (!avahi_is_valid_domain_name(domain))
457
0
        return AVAHI_ERR_INVALID_DOMAIN_NAME;
458
459
    /* Preparation */
460
461
1.33k
    if (name) {
462
524
        size_t l = sizeof(escaped_name);
463
524
        char *e = escaped_name, *r;
464
524
        r = avahi_escape_label(name, strlen(name), &e, &l);
465
524
        assert(r);
466
524
    }
467
468
1.33k
    if (!(avahi_normalize_name(type, normalized_type, sizeof(normalized_type))))
469
0
        return AVAHI_ERR_INVALID_SERVICE_TYPE;
470
471
1.33k
    if (!(avahi_normalize_name(domain, normalized_domain, sizeof(normalized_domain))))
472
0
        return AVAHI_ERR_INVALID_DOMAIN_NAME;
473
474
    /* Concatenation */
475
476
1.33k
    snprintf(p, size, "%s%s%s.%s", name ? escaped_name : "", name ? "." : "", normalized_type, normalized_domain);
477
478
1.33k
    return AVAHI_OK;
479
1.33k
}
480
481
#ifndef HAVE_STRLCPY
482
483
3.28k
static size_t strlcpy(char *dest, const char *src, size_t n) {
484
3.28k
    assert(dest);
485
3.28k
    assert(src);
486
487
3.28k
    if (n > 0) {
488
3.28k
        strncpy(dest, src, n-1);
489
3.28k
        dest[n-1] = 0;
490
3.28k
    }
491
492
3.28k
    return strlen(src);
493
3.28k
}
494
495
#endif
496
497
7.72k
int avahi_service_name_split(const char *p, char *name, size_t name_size, char *type, size_t type_size, char *domain, size_t domain_size) {
498
7.72k
    enum {
499
7.72k
        NAME,
500
7.72k
        TYPE,
501
7.72k
        DOMAIN
502
7.72k
    } state;
503
7.72k
    int type_empty = 1, domain_empty = 1;
504
7.72k
    char *oname, *otype, *odomain;
505
506
7.72k
    assert(p);
507
7.72k
    assert(type);
508
7.72k
    assert(type_size > 0);
509
7.72k
    assert(domain);
510
7.72k
    assert(domain_size > 0);
511
512
7.72k
    oname = name;
513
7.72k
    otype = type;
514
7.72k
    odomain = domain;
515
516
7.72k
    if (name) {
517
3.86k
        assert(name_size > 0);
518
3.86k
        *name = 0;
519
3.86k
        state = NAME;
520
3.86k
    } else
521
3.86k
        state = TYPE;
522
523
7.72k
    *type = *domain = 0;
524
525
31.1k
    while (*p) {
526
23.4k
        char buf[64];
527
528
23.4k
        if (!(avahi_unescape_label(&p, buf, sizeof(buf))))
529
0
            return -1;
530
531
23.4k
        switch (state) {
532
3.28k
            case NAME:
533
3.28k
                strlcpy(name, buf, name_size);
534
3.28k
                state = TYPE;
535
3.28k
                break;
536
537
16.6k
            case TYPE:
538
539
16.6k
                if (buf[0] == '_') {
540
541
14.6k
                    if (!type_empty) {
542
8.85k
                        if (!type_size)
543
0
                            return AVAHI_ERR_NO_MEMORY;
544
545
8.85k
                        *(type++) = '.';
546
8.85k
                        type_size --;
547
548
8.85k
                    } else
549
5.78k
                        type_empty = 0;
550
551
14.6k
                    if (!(avahi_escape_label(buf, strlen(buf), &type, &type_size)))
552
0
                        return AVAHI_ERR_NO_MEMORY;
553
554
14.6k
                    break;
555
14.6k
                }
556
557
2.04k
                state = DOMAIN;
558
                /* fall through */
559
560
5.50k
            case DOMAIN:
561
562
5.50k
                if (!domain_empty) {
563
3.45k
                    if (!domain_size)
564
0
                        return AVAHI_ERR_NO_MEMORY;
565
566
3.45k
                    *(domain++) = '.';
567
3.45k
                    domain_size --;
568
3.45k
                } else
569
2.04k
                    domain_empty = 0;
570
571
5.50k
                if (!(avahi_escape_label(buf, strlen(buf), &domain, &domain_size)))
572
0
                    return AVAHI_ERR_NO_MEMORY;
573
574
5.50k
                break;
575
23.4k
        }
576
23.4k
    }
577
578
7.72k
    if ((oname && !avahi_is_valid_service_name(oname)))
579
584
        return AVAHI_ERR_INVALID_SERVICE_NAME;
580
581
7.14k
    if (!avahi_is_valid_service_type_strict(otype) && !avahi_is_valid_service_subtype(otype))
582
5.81k
        return AVAHI_ERR_INVALID_SERVICE_TYPE;
583
584
1.33k
    if (!avahi_is_valid_domain_name(odomain))
585
0
        return AVAHI_ERR_INVALID_DOMAIN_NAME;
586
587
1.33k
    return 0;
588
1.33k
}
589
590
933
int avahi_is_valid_fqdn(const char *t) {
591
933
    char label[AVAHI_LABEL_MAX];
592
933
    char normalized[AVAHI_DOMAIN_NAME_MAX];
593
933
    const char *k = t;
594
933
    AvahiAddress a;
595
933
    assert(t);
596
597
933
    if (strlen(t) >= AVAHI_DOMAIN_NAME_MAX)
598
42
        return 0;
599
600
891
    if (!avahi_is_valid_domain_name(t))
601
211
        return 0;
602
603
    /* Check if there are at least two labels*/
604
680
    if (!(avahi_unescape_label(&k, label, sizeof(label))))
605
0
        return 0;
606
607
680
    if (label[0] == 0 || !k)
608
3
        return 0;
609
610
677
    if (!(avahi_unescape_label(&k, label, sizeof(label))))
611
0
        return 0;
612
613
677
    if (label[0] == 0 || !k)
614
394
        return 0;
615
616
    /* Make sure that the name is not an IP address */
617
283
    if (!(avahi_normalize_name(t, normalized, sizeof(normalized))))
618
10
        return 0;
619
620
273
    if (avahi_address_parse(normalized, AVAHI_PROTO_UNSPEC, &a))
621
1
        return 0;
622
623
272
    return 1;
624
273
}