translate DNS queries to avahi-resolve
initial import
+624
+13
LICENSE
+13
LICENSE
···
1
+
Copyright (c) 2026 joshua stein <jcs@jcs.org>
2
+
3
+
Permission to use, copy, modify, and distribute this software for any
4
+
purpose with or without fee is hereby granted, provided that the above
5
+
copyright notice and this permission notice appear in all copies.
6
+
7
+
THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
8
+
WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
9
+
MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
10
+
ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
11
+
WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
12
+
ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
13
+
OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+35
Makefile
+35
Makefile
···
1
+
CC ?= cc
2
+
CFLAGS = -O2 -Wall -Wextra -Wunused -Wmissing-prototypes -Wstrict-prototypes
3
+
CFLAGS += -g
4
+
5
+
INSTALL_PROGRAM ?= install
6
+
7
+
PREFIX ?= /usr/local
8
+
BINDIR ?= $(PREFIX)/bin
9
+
10
+
PROG = avahi-proxy
11
+
OBJS = avahi-proxy.o
12
+
13
+
RC = avahi_proxy.rc
14
+
RCDEST = avahi_proxy
15
+
16
+
all: $(PROG)
17
+
18
+
clean:
19
+
rm -f $(PROG) $(OBJS)
20
+
21
+
$(PROG): $(OBJS)
22
+
$(CC) $(OBJS) -o $@
23
+
24
+
$(OBJS): *.c
25
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$(CC) $(CFLAGS) -c avahi-proxy.c -o $@
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+
27
+
install: all
28
+
mkdir -p $(DESTDIR)$(BINDIR)
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$(INSTALL_PROGRAM) -s $(PROG) $(DESTDIR)$(BINDIR)
30
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$(INSTALL_PROGRAM) $(RC) /etc/rc.d/$(RCDEST)
31
+
32
+
clean:
33
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rm -f $(PROG) $(OBJS)
34
+
35
+
.PHONY: all install clean
+43
README.md
+43
README.md
···
1
+
# avahi-proxy
2
+
3
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Act as a DNS server listening on a given port (and optional IP, otherwise
4
+
defaulting to `127.0.0.1`) and pass each `A` and `AAAA` query received for the
5
+
`local` domain to `avahi-resolve`.
6
+
If it gets an answer, pass it back as a proper DNS reply, otherwise return
7
+
`NXDOMAIN`.
8
+
9
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## Compiling
10
+
11
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$ git clone https://github.com/jcs/avahi-proxy
12
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$ cd avahi-proxy
13
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avahi-proxy$ make
14
+
15
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## Installing
16
+
17
+
avahi-proxy$ doas make install
18
+
avahi-proxy$ doas rcctl enable avahi_proxy
19
+
avahi-proxy$ doas rcctl start avahi_proxy
20
+
21
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## Use with `unwind`
22
+
23
+
When using OpenBSD's `unwind`, configure a `force` block for `local.` and a
24
+
`forwarder` to `avahi-proxy`, assuming its default port of 5300:
25
+
26
+
preference { autoconf }
27
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forwarder { 127.0.0.1 port 5300 }
28
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force forwarder { local }
29
+
30
+
Now queries for `local.` hosts will forward to `avahi-proxy`, which will proxy
31
+
them to `avahi-resolve`:
32
+
33
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$ dig @127.0.0.1 giraffe.local. a
34
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[...]
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;; QUESTION SECTION:
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;giraffe.local. IN A
37
+
38
+
;; ANSWER SECTION:
39
+
giraffe.local. 9 IN A 192.168.1.3
40
+
41
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To directly query `avahi-daemon`, just supply the port it's running on:
42
+
43
+
$ dig @127.0.0.1 -p 5300 giraffe.local. a
+524
avahi-proxy.c
+524
avahi-proxy.c
···
1
+
/*
2
+
* Copyright (c) 2026 joshua stein <jcs@jcs.org>
3
+
*
4
+
* Permission to use, copy, modify, and distribute this software for any
5
+
* purpose with or without fee is hereby granted, provided that the above
6
+
* copyright notice and this permission notice appear in all copies.
7
+
*
8
+
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
9
+
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
10
+
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
11
+
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
12
+
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
13
+
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
14
+
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
15
+
*/
16
+
17
+
#include <sys/types.h>
18
+
#include <sys/socket.h>
19
+
#include <sys/wait.h>
20
+
21
+
#include <arpa/inet.h>
22
+
#include <netinet/in.h>
23
+
24
+
#include <err.h>
25
+
#include <errno.h>
26
+
#include <netdb.h>
27
+
#include <signal.h>
28
+
#include <stdarg.h>
29
+
#include <stdio.h>
30
+
#include <stdlib.h>
31
+
#include <string.h>
32
+
#include <syslog.h>
33
+
#include <unistd.h>
34
+
35
+
#define DNS_HEADER_SIZE 12
36
+
#define DNS_MAX_NAME 255
37
+
#define DNS_MAX_LABEL 63
38
+
#define DNS_TYPE_A 1
39
+
#define DNS_TYPE_NS 2
40
+
#define DNS_TYPE_AAAA 28
41
+
#define DNS_CLASS_IN 1
42
+
#define DNS_RCODE_NOERROR 0
43
+
#define DNS_RCODE_NXDOMAIN 3
44
+
45
+
#define DNS_FLAG_QR 0x8000 /* response */
46
+
#define DNS_FLAG_AA 0x0400 /* authoritative */
47
+
#define DNS_FLAG_RD 0x0100 /* recursion desired */
48
+
#define DNS_FLAG_RA 0x0080 /* recursion available */
49
+
50
+
int debug, verbose;
51
+
52
+
__dead void usage(void);
53
+
void logmsg(const char *, ...);
54
+
int dns_parse_name(uint8_t *, size_t, size_t, char *, size_t, size_t *);
55
+
const char *dns_type_str(uint16_t);
56
+
size_t dns_build_response(uint8_t *, size_t, uint8_t *, size_t, uint16_t,
57
+
void *, size_t);
58
+
size_t dns_build_ns_response(uint8_t *, size_t, uint8_t *);
59
+
size_t dns_build_nxdomain(uint8_t *, size_t, uint8_t *, size_t);
60
+
int avahi_resolve(const char *, int, void *);
61
+
62
+
__dead void
63
+
usage(void)
64
+
{
65
+
extern char *__progname;
66
+
67
+
fprintf(stderr, "usage: %s [-dv] [-b address] -p port\n", __progname);
68
+
exit(1);
69
+
}
70
+
71
+
void
72
+
logmsg(const char *fmt, ...)
73
+
{
74
+
va_list ap;
75
+
76
+
va_start(ap, fmt);
77
+
if (debug)
78
+
vprintf(fmt, ap);
79
+
else
80
+
vsyslog(LOG_INFO, fmt, ap);
81
+
va_end(ap);
82
+
}
83
+
84
+
int
85
+
main(int argc, char *argv[])
86
+
{
87
+
struct addrinfo hints, *res, *res0;
88
+
struct sockaddr_storage ss;
89
+
struct in_addr addr4;
90
+
struct in6_addr addr6;
91
+
socklen_t sslen;
92
+
ssize_t n;
93
+
size_t namelen, qnamelen, resplen;
94
+
char name[DNS_MAX_NAME + 1];
95
+
const char *bindaddr = NULL;
96
+
const char *port = NULL;
97
+
uint8_t qbuf[512], rbuf[512];
98
+
uint16_t qtype, qclass;
99
+
int ch, error, s;
100
+
101
+
while ((ch = getopt(argc, argv, "b:dp:v")) != -1) {
102
+
switch (ch) {
103
+
case 'b':
104
+
bindaddr = optarg;
105
+
break;
106
+
case 'd':
107
+
debug = 1;
108
+
break;
109
+
case 'p':
110
+
port = optarg;
111
+
break;
112
+
case 'v':
113
+
verbose++;
114
+
break;
115
+
default:
116
+
usage();
117
+
}
118
+
}
119
+
argc -= optind;
120
+
argv += optind;
121
+
122
+
if (port == NULL)
123
+
usage();
124
+
125
+
if (!debug) {
126
+
if (daemon(0, 0) == -1)
127
+
err(1, "daemon");
128
+
openlog("avahi-proxy", LOG_PID | LOG_NDELAY, LOG_DAEMON);
129
+
}
130
+
131
+
signal(SIGPIPE, SIG_IGN);
132
+
133
+
memset(&hints, 0, sizeof(hints));
134
+
hints.ai_family = AF_UNSPEC;
135
+
hints.ai_socktype = SOCK_DGRAM;
136
+
hints.ai_flags = AI_PASSIVE;
137
+
138
+
error = getaddrinfo(bindaddr, port, &hints, &res0);
139
+
if (error != 0)
140
+
errx(1, "getaddrinfo: %s", gai_strerror(error));
141
+
142
+
s = -1;
143
+
for (res = res0; res != NULL; res = res->ai_next) {
144
+
s = socket(res->ai_family, res->ai_socktype, res->ai_protocol);
145
+
if (s == -1)
146
+
continue;
147
+
if (bind(s, res->ai_addr, res->ai_addrlen) == -1) {
148
+
close(s);
149
+
s = -1;
150
+
continue;
151
+
}
152
+
break;
153
+
}
154
+
freeaddrinfo(res0);
155
+
156
+
if (s == -1)
157
+
err(1, "socket/bind");
158
+
159
+
for (;;) {
160
+
sslen = sizeof(ss);
161
+
n = recvfrom(s, qbuf, sizeof(qbuf), 0, (struct sockaddr *)&ss,
162
+
&sslen);
163
+
if (n == -1) {
164
+
if (errno == EINTR)
165
+
continue;
166
+
warn("recvfrom");
167
+
continue;
168
+
}
169
+
170
+
if (n < DNS_HEADER_SIZE)
171
+
continue;
172
+
173
+
/* parse question */
174
+
if (dns_parse_name(qbuf, n, DNS_HEADER_SIZE, name, sizeof(name),
175
+
&qnamelen) == -1) {
176
+
warnx("failed parsing DNS query");
177
+
continue;
178
+
}
179
+
180
+
if (DNS_HEADER_SIZE + qnamelen + 4 > (size_t)n) {
181
+
warnx("bogus qnamelen %zu + 4 > %zu", qnamelen, n);
182
+
continue;
183
+
}
184
+
185
+
qtype = (qbuf[DNS_HEADER_SIZE + qnamelen] << 8) |
186
+
qbuf[DNS_HEADER_SIZE + qnamelen + 1];
187
+
qclass = (qbuf[DNS_HEADER_SIZE + qnamelen + 2] << 8) |
188
+
qbuf[DNS_HEADER_SIZE + qnamelen + 3];
189
+
190
+
if (qclass != DNS_CLASS_IN) {
191
+
if (verbose)
192
+
logmsg("ignoring query for non-IN (%d) name "
193
+
"%s\n", qclass, name);
194
+
continue;
195
+
}
196
+
197
+
/* respond to ". NS" probe from unwind */
198
+
if (strcmp(name, ".") == 0 && qtype == DNS_TYPE_NS) {
199
+
resplen = dns_build_ns_response(rbuf, sizeof(rbuf),
200
+
qbuf);
201
+
if (verbose)
202
+
logmsg("%s %s -> localhost.\n",
203
+
dns_type_str(qtype), name);
204
+
} else if ((namelen = strlen(name)) >= 6 &&
205
+
strcasecmp(name + namelen - 6, ".local") == 0 &&
206
+
qtype == DNS_TYPE_A &&
207
+
avahi_resolve(name, AF_INET, &addr4) == 0) {
208
+
resplen = dns_build_response(rbuf, sizeof(rbuf),
209
+
qbuf, n, DNS_TYPE_A, &addr4, 4);
210
+
} else if (namelen >= 6 &&
211
+
strcasecmp(name + namelen - 6, ".local") == 0 &&
212
+
qtype == DNS_TYPE_AAAA &&
213
+
avahi_resolve(name, AF_INET6, &addr6) == 0) {
214
+
resplen = dns_build_response(rbuf, sizeof(rbuf),
215
+
qbuf, n, DNS_TYPE_AAAA, &addr6, 16);
216
+
} else {
217
+
resplen = dns_build_nxdomain(rbuf, sizeof(rbuf),
218
+
qbuf, n);
219
+
if (verbose)
220
+
logmsg("%s %s NXDOMAIN\n",
221
+
dns_type_str(qtype), name);
222
+
}
223
+
224
+
if (resplen > 0)
225
+
sendto(s, rbuf, resplen, 0, (struct sockaddr *)&ss,
226
+
sslen);
227
+
}
228
+
229
+
return 0;
230
+
}
231
+
232
+
int
233
+
dns_parse_name(uint8_t *pkt, size_t pktlen, size_t offset, char *dst,
234
+
size_t dstlen, size_t *lenp)
235
+
{
236
+
size_t i, label_len, total = 0, dst_off = 0;
237
+
238
+
for (;;) {
239
+
if (offset >= pktlen)
240
+
return -1;
241
+
242
+
label_len = pkt[offset++];
243
+
total++;
244
+
245
+
if (label_len == 0) {
246
+
/* root label */
247
+
if (dst_off == 0) {
248
+
if (dstlen < 2)
249
+
return -1;
250
+
dst[dst_off++] = '.';
251
+
}
252
+
dst[dst_off] = '\0';
253
+
*lenp = total;
254
+
return 0;
255
+
}
256
+
257
+
if (label_len > DNS_MAX_LABEL)
258
+
return -1;
259
+
if (offset + label_len > pktlen)
260
+
return -1;
261
+
if (dst_off + label_len + 1 >= dstlen)
262
+
return -1;
263
+
264
+
if (dst_off > 0)
265
+
dst[dst_off++] = '.';
266
+
267
+
for (i = 0; i < label_len; i++)
268
+
dst[dst_off++] = pkt[offset++];
269
+
total += label_len;
270
+
}
271
+
}
272
+
273
+
const char *
274
+
dns_type_str(uint16_t type)
275
+
{
276
+
switch (type) {
277
+
case DNS_TYPE_A:
278
+
return "A";
279
+
case DNS_TYPE_NS:
280
+
return "NS";
281
+
case DNS_TYPE_AAAA:
282
+
return "AAAA";
283
+
default:
284
+
return "?";
285
+
}
286
+
}
287
+
288
+
size_t
289
+
dns_build_response(uint8_t *rbuf, size_t rlen, uint8_t *qbuf, size_t qlen,
290
+
uint16_t type, void *addr, size_t addrlen)
291
+
{
292
+
size_t off, qsec_len;
293
+
uint16_t flags;
294
+
295
+
/* question section length: from byte 12 to end of qtype/qclass */
296
+
for (qsec_len = 0; DNS_HEADER_SIZE + qsec_len < qlen; qsec_len++) {
297
+
if (qbuf[DNS_HEADER_SIZE + qsec_len] == 0) {
298
+
qsec_len += 5; /* null + qtype(2) + qclass(2) */
299
+
break;
300
+
}
301
+
}
302
+
303
+
if (DNS_HEADER_SIZE + qsec_len + 12 + addrlen > rlen) {
304
+
warnx("%s: bogus size (%d + %zu + 12 + %zu) > %zu",
305
+
__func__, DNS_HEADER_SIZE, qsec_len, addrlen, rlen);
306
+
return 0;
307
+
}
308
+
309
+
/* copy header and question */
310
+
memcpy(rbuf, qbuf, DNS_HEADER_SIZE + qsec_len);
311
+
312
+
/* set response flags */
313
+
flags = DNS_FLAG_QR | DNS_FLAG_AA | DNS_FLAG_RA;
314
+
if (qbuf[2] & (DNS_FLAG_RD >> 8))
315
+
flags |= DNS_FLAG_RD;
316
+
rbuf[2] = flags >> 8;
317
+
rbuf[3] = flags & 0xff;
318
+
319
+
/* qdcount = 1 */
320
+
rbuf[4] = 0; rbuf[5] = 1;
321
+
/* ancount = 1 */
322
+
rbuf[6] = 0; rbuf[7] = 1;
323
+
/* nscount = 0 */
324
+
rbuf[8] = 0; rbuf[9] = 0;
325
+
/* arcount = 0 */
326
+
rbuf[10] = 0; rbuf[11] = 0;
327
+
328
+
off = DNS_HEADER_SIZE + qsec_len;
329
+
330
+
/* answer: pointer to qname */
331
+
rbuf[off++] = 0xc0;
332
+
rbuf[off++] = 0x0c;
333
+
/* type */
334
+
rbuf[off++] = type >> 8;
335
+
rbuf[off++] = type & 0xff;
336
+
/* class IN */
337
+
rbuf[off++] = 0;
338
+
rbuf[off++] = DNS_CLASS_IN;
339
+
/* TTL = 60 */
340
+
rbuf[off++] = 0;
341
+
rbuf[off++] = 0;
342
+
rbuf[off++] = 0;
343
+
rbuf[off++] = 60;
344
+
/* rdlength */
345
+
rbuf[off++] = addrlen >> 8;
346
+
rbuf[off++] = addrlen & 0xff;
347
+
/* rdata */
348
+
memcpy(rbuf + off, addr, addrlen);
349
+
off += addrlen;
350
+
351
+
return off;
352
+
}
353
+
354
+
size_t
355
+
dns_build_ns_response(uint8_t *rbuf, size_t rlen, uint8_t *qbuf)
356
+
{
357
+
/* "localhost." in wire format */
358
+
static uint8_t localhost[] = {
359
+
9, 'l','o','c','a','l','h','o','s','t', '\0'
360
+
};
361
+
size_t off, qsec_len;
362
+
uint16_t flags;
363
+
364
+
/* question: null label + qtype(2) + qclass(2) = 5 bytes for "." */
365
+
qsec_len = 5;
366
+
367
+
if (DNS_HEADER_SIZE + qsec_len + 12 + sizeof(localhost) > rlen) {
368
+
warnx("%s: bogus size (%d + %zu + 12 + %zu) > %zu",
369
+
__func__, DNS_HEADER_SIZE, qsec_len, sizeof(localhost),
370
+
rlen);
371
+
return 0;
372
+
}
373
+
374
+
/* copy header and question */
375
+
memcpy(rbuf, qbuf, DNS_HEADER_SIZE + qsec_len);
376
+
377
+
/* set response flags */
378
+
flags = DNS_FLAG_QR | DNS_FLAG_AA | DNS_FLAG_RA;
379
+
if (qbuf[2] & (DNS_FLAG_RD >> 8))
380
+
flags |= DNS_FLAG_RD;
381
+
rbuf[2] = flags >> 8;
382
+
rbuf[3] = flags & 0xff;
383
+
384
+
/* qdcount = 1 */
385
+
rbuf[4] = 0; rbuf[5] = 1;
386
+
/* ancount = 1 */
387
+
rbuf[6] = 0; rbuf[7] = 1;
388
+
/* nscount = 0 */
389
+
rbuf[8] = 0; rbuf[9] = 0;
390
+
/* arcount = 0 */
391
+
rbuf[10] = 0; rbuf[11] = 0;
392
+
393
+
off = DNS_HEADER_SIZE + qsec_len;
394
+
395
+
/* answer: pointer to qname */
396
+
rbuf[off++] = 0xc0;
397
+
rbuf[off++] = 0x0c;
398
+
/* type NS */
399
+
rbuf[off++] = 0;
400
+
rbuf[off++] = DNS_TYPE_NS;
401
+
/* class IN */
402
+
rbuf[off++] = 0;
403
+
rbuf[off++] = DNS_CLASS_IN;
404
+
/* TTL = 86400 */
405
+
rbuf[off++] = 0;
406
+
rbuf[off++] = 0x01;
407
+
rbuf[off++] = 0x51;
408
+
rbuf[off++] = 0x80;
409
+
/* rdlength */
410
+
rbuf[off++] = 0;
411
+
rbuf[off++] = sizeof(localhost);
412
+
/* rdata: localhost. */
413
+
memcpy(rbuf + off, localhost, sizeof(localhost));
414
+
off += sizeof(localhost);
415
+
416
+
return off;
417
+
}
418
+
419
+
size_t
420
+
dns_build_nxdomain(uint8_t *rbuf, size_t rlen, uint8_t *qbuf, size_t qlen)
421
+
{
422
+
size_t qsec_len;
423
+
uint16_t flags;
424
+
425
+
/* find question section length */
426
+
for (qsec_len = 0; DNS_HEADER_SIZE + qsec_len < qlen; qsec_len++) {
427
+
if (qbuf[DNS_HEADER_SIZE + qsec_len] == 0) {
428
+
qsec_len += 5; /* null + qtype(2) + qclass(2) */
429
+
break;
430
+
}
431
+
}
432
+
433
+
if (DNS_HEADER_SIZE + qsec_len > rlen) {
434
+
warnx("%s: bogus size (%d + %zu) > %zu",
435
+
__func__, DNS_HEADER_SIZE, qsec_len, rlen);
436
+
return 0;
437
+
}
438
+
439
+
/* copy header and question */
440
+
memcpy(rbuf, qbuf, DNS_HEADER_SIZE + qsec_len);
441
+
442
+
/* set response flags with NXDOMAIN rcode */
443
+
flags = DNS_FLAG_QR | DNS_FLAG_AA | DNS_FLAG_RA;
444
+
if (qbuf[2] & (DNS_FLAG_RD >> 8))
445
+
flags |= DNS_FLAG_RD;
446
+
rbuf[2] = flags >> 8;
447
+
rbuf[3] = (flags & 0xff) | DNS_RCODE_NXDOMAIN;
448
+
449
+
/* qdcount = 1 */
450
+
rbuf[4] = 0; rbuf[5] = 1;
451
+
/* ancount = 0 */
452
+
rbuf[6] = 0; rbuf[7] = 0;
453
+
/* nscount = 0 */
454
+
rbuf[8] = 0; rbuf[9] = 0;
455
+
/* arcount = 0 */
456
+
rbuf[10] = 0; rbuf[11] = 0;
457
+
458
+
return DNS_HEADER_SIZE + qsec_len;
459
+
}
460
+
461
+
int
462
+
avahi_resolve(const char *name, int af, void *addr)
463
+
{
464
+
char buf[128], *tab, abuf[INET6_ADDRSTRLEN];
465
+
ssize_t n;
466
+
pid_t pid;
467
+
int pipefd[2], status;
468
+
469
+
if (pipe(pipefd) == -1)
470
+
return -1;
471
+
472
+
pid = fork();
473
+
if (pid == -1) {
474
+
close(pipefd[0]);
475
+
close(pipefd[1]);
476
+
return -1;
477
+
}
478
+
479
+
if (pid == 0) {
480
+
close(pipefd[0]);
481
+
if (dup2(pipefd[1], STDOUT_FILENO) == -1)
482
+
_exit(1);
483
+
close(pipefd[1]);
484
+
execlp("avahi-resolve", "avahi-resolve",
485
+
af == AF_INET6 ? "-6" : "-4",
486
+
"-n", name,
487
+
(char *)NULL);
488
+
_exit(1);
489
+
}
490
+
491
+
close(pipefd[1]);
492
+
493
+
n = read(pipefd[0], buf, sizeof(buf) - 1);
494
+
close(pipefd[0]);
495
+
496
+
if (waitpid(pid, &status, 0) == -1 || !WIFEXITED(status) ||
497
+
WEXITSTATUS(status) != 0)
498
+
return -1;
499
+
500
+
if (n <= 0)
501
+
return -1;
502
+
503
+
buf[n] = '\0';
504
+
505
+
/* strip trailing newline */
506
+
while (n > 0 && (buf[n - 1] == '\n' || buf[n - 1] == '\r'))
507
+
buf[--n] = '\0';
508
+
509
+
/* avahi-resolve output: "hostname.local\t192.168.1.1\n" */
510
+
tab = strchr(buf, '\t');
511
+
if (tab == NULL)
512
+
return -1;
513
+
514
+
if (inet_pton(af, tab + 1, addr) != 1)
515
+
return -1;
516
+
517
+
if (verbose) {
518
+
inet_ntop(af, addr, abuf, sizeof(abuf));
519
+
logmsg("%s %s -> %s\n", af == AF_INET6 ? "AAAA" : "A",
520
+
name, abuf);
521
+
}
522
+
523
+
return 0;
524
+
}