2 * Copyright (C) 2014 John Crispin <blogic@openwrt.org>
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU Lesser General Public License version 2.1
6 * as published by the Free Software Foundation
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
11 * GNU General Public License for more details.
15 #include <sys/types.h>
23 #include <sys/types.h>
24 #include <sys/socket.h>
25 #include <netinet/in.h>
26 #include <arpa/inet.h>
27 #include <arpa/nameser.h>
31 #include <libubox/usock.h>
32 #include <libubox/uloop.h>
33 #include <libubox/avl-cmp.h>
34 #include <libubox/blobmsg_json.h>
35 #include <libubox/kvlist.h>
41 #include "interface.h"
43 static struct uloop_timeout cache_gc
;
44 struct avl_tree services
;
45 static AVL_TREE(records
, avl_strcmp
, true, NULL
);
48 cache_record_free(struct cache_record
*r
)
50 DBG(2, "%s %s\n", dns_type_string(r
->type
), r
->record
);
51 avl_delete(&records
, &r
->avl
);
56 cache_service_free(struct cache_service
*s
)
58 DBG(2, "%s\n", s
->entry
);
59 avl_delete(&services
, &s
->avl
);
64 cache_is_expired(time_t t
, uint32_t ttl
, int frac
)
66 if (monotonic_time() - t
>= ttl
* frac
/ 100)
73 cache_gc_timer(struct uloop_timeout
*timeout
)
75 struct cache_record
*r
, *p
;
76 struct cache_service
*s
, *t
;
78 avl_for_each_element_safe(&records
, r
, avl
, p
)
79 if (cache_is_expired(r
->time
, r
->ttl
, 100))
82 avl_for_each_element_safe(&services
, s
, avl
, t
) {
85 if (!cache_is_expired(s
->time
, s
->ttl
, s
->refresh
))
87 if (s
->refresh
>= 100) {
88 cache_service_free(s
);
92 if (cache_service_is_host(s
)) {
93 dns_send_question(s
->iface
, s
->entry
, TYPE_A
, 0);
94 dns_send_question(s
->iface
, s
->entry
, TYPE_AAAA
, 0);
96 dns_send_question(s
->iface
, s
->entry
, TYPE_PTR
, 0);
100 uloop_timeout_set(timeout
, 10000);
106 avl_init(&services
, avl_strcmp
, true, NULL
);
108 cache_gc
.cb
= cache_gc_timer
;
109 uloop_timeout_set(&cache_gc
, 10000);
114 void cache_cleanup(struct interface
*iface
)
116 struct cache_record
*r
, *p
;
117 struct cache_service
*s
, *t
;
119 avl_for_each_element_safe(&services
, s
, avl
, t
)
120 if (!iface
|| iface
== s
->iface
)
121 cache_service_free(s
);
123 avl_for_each_element_safe(&records
, r
, avl
, p
)
124 if (!iface
|| iface
== r
->iface
)
125 cache_record_free(r
);
131 struct interface
*iface
;
132 struct cache_service
*s
;
134 vlist_for_each_element(&interfaces
, iface
, node
)
135 avl_for_each_element(&services
, s
, avl
)
136 dns_send_question(iface
, s
->entry
, TYPE_PTR
, 0);
139 static struct cache_service
*
140 cache_service(struct interface
*iface
, char *entry
, int hlen
, int ttl
)
142 struct cache_service
*s
, *t
;
147 avl_for_each_element_safe(&services
, s
, avl
, t
)
148 if (!strcmp(s
->entry
, entry
)) {
150 s
->time
= monotonic_time();
155 s
= calloc_a(sizeof(*s
),
156 &entry_buf
, strlen(entry
) + 1,
157 &host_buf
, hlen
? hlen
+ 1 : 0);
159 s
->avl
.key
= s
->entry
= strcpy(entry_buf
, entry
);
160 s
->time
= monotonic_time();
166 s
->host
= strncpy(host_buf
, s
->entry
, hlen
);
168 type
= strstr(entry_buf
, "._");
173 avl_insert(&services
, &s
->avl
);
176 dns_send_question(iface
, entry
, TYPE_PTR
, iface
->multicast
);
181 static struct cache_record
*
182 cache_record_find(char *record
, int type
, int port
, int rdlength
, uint8_t *rdata
)
184 struct cache_record
*l
= avl_find_element(&records
, record
, l
, avl
);
189 while (l
&& l
->record
&& !strcmp(l
->record
, record
)) {
190 struct cache_record
*r
= l
;
192 l
= avl_next_element(l
, avl
);
196 if (r
->type
== TYPE_TXT
|| (r
->type
== TYPE_SRV
))
202 if (r
->rdlength
!= rdlength
)
205 if (!!r
->rdata
!= !!rdata
)
208 if (!r
->rdata
|| !rdata
|| memcmp(r
->rdata
, rdata
, rdlength
))
218 cache_host_is_known(char *record
)
220 struct cache_record
*l
= avl_find_element(&records
, record
, l
, avl
);
225 while (l
&& !avl_is_last(&records
, &l
->avl
) && !strcmp(l
->record
, record
)) {
226 struct cache_record
*r
= l
;
228 l
= avl_next_element(l
, avl
);
229 if ((r
->type
!= TYPE_A
) && (r
->type
!= TYPE_AAAA
))
238 cache_answer(struct interface
*iface
, uint8_t *base
, int blen
, char *name
, struct dns_answer
*a
, uint8_t *rdata
, int flush
)
240 struct dns_srv_data
*dsd
= (struct dns_srv_data
*) rdata
;
241 struct cache_record
*r
;
242 int port
= 0, dlen
= 0, tlen
= 0, nlen
, rdlength
;
245 void *rdata_ptr
, *txt_ptr
;
247 static char *rdata_buffer
= (char *) mdns_buf
;
248 time_t now
= monotonic_time();
257 if (dn_expand(base
, base
+ blen
, rdata
, rdata_buffer
, MAX_DATA_LEN
) < 0) {
258 perror("process_answer/dn_expand");
262 DBG(1, "A -> %s %s %s ttl:%d\n", dns_type_string(a
->type
), name
, rdata_buffer
, a
->ttl
);
264 rdlength
= strlen(rdata_buffer
);
266 if (strcmp(C_DNS_SD
, name
) != 0 &&
267 nlen
+ 1 < rdlength
&& !strcmp(rdata_buffer
+ rdlength
- nlen
, name
))
268 host_len
= rdlength
- nlen
- 1;
270 cache_service(iface
, rdata_buffer
, host_len
, a
->ttl
);
272 dlen
= strlen(rdata_buffer
) + 1;
273 rdata
= (uint8_t*)rdata_buffer
;
280 port
= be16_to_cpu(dsd
->port
);
281 memcpy(rdata_buffer
, dsd
, sizeof(*dsd
));
282 if (dn_expand(base
, base
+ blen
, (const uint8_t*)&dsd
[1],
283 &rdata_buffer
[sizeof(*dsd
)], MAX_DATA_LEN
- sizeof(*dsd
)) < 0) {
284 perror("process_answer/dn_expand");
287 dlen
= sizeof(*dsd
) + strlen(&rdata_buffer
[sizeof(*dsd
)]) + 1;
288 rdata
= (uint8_t*)rdata_buffer
;
292 rdlength
= a
->rdlength
;
296 memcpy(rdata_buffer
, &rdata
[1], rdlength
);
297 rdata_buffer
[rdlength
] = rdata_buffer
[rdlength
+ 1] = '\0';
299 p
= &rdata_buffer
[*rdata
];
305 if (v
&& p
+ v
< &rdata_buffer
[rdlength
])
311 cache_service(iface
, name
, strlen(name
), a
->ttl
);
312 if (a
->rdlength
!= 4)
318 cache_service(iface
, name
, strlen(name
), a
->ttl
);
319 if (a
->rdlength
!= 16)
328 r
= cache_record_find(name
, a
->type
, port
, dlen
, rdata
);
331 DBG(1, "D -> %s %s ttl:%d\n", dns_type_string(r
->type
), r
->record
, r
->ttl
);
332 r
->time
= now
+ 1 - r
->ttl
;
336 DBG(1, "A -> %s %s ttl:%d\n", dns_type_string(r
->type
), r
->record
, r
->ttl
);
344 r
= calloc_a(sizeof(*r
),
345 &name_buf
, strlen(name
) + 1,
349 r
->avl
.key
= r
->record
= strcpy(name_buf
, name
);
358 r
->txt
= memcpy(txt_ptr
, rdata_buffer
, tlen
);
361 r
->rdata
= memcpy(rdata_ptr
, rdata
, dlen
);
363 if (avl_insert(&records
, &r
->avl
))
366 DBG(1, "A -> %s %s ttl:%d\n", dns_type_string(r
->type
), r
->record
, r
->ttl
);
370 cache_dump_records(struct blob_buf
*buf
, const char *name
)
372 struct cache_record
*r
, *last
, *next
;
374 char buffer
[INET6_ADDRSTRLEN
];
376 last
= avl_last_element(&records
, last
, avl
);
377 for (r
= avl_find_element(&records
, name
, r
, avl
); r
; r
= next
) {
380 if (r
->txt
&& strlen(r
->txt
)) {
383 blobmsg_add_string(buf
, "txt", txt
);
384 txt
= &txt
[strlen(txt
) + 1];
391 blobmsg_add_u32(buf
, "port", r
->port
);
395 if ((r
->rdlength
== 4) && inet_ntop(AF_INET
, r
->rdata
, buffer
, INET6_ADDRSTRLEN
))
396 blobmsg_add_string(buf
, "ipv4", buffer
);
400 if ((r
->rdlength
== 16) && inet_ntop(AF_INET6
, r
->rdata
, buffer
, INET6_ADDRSTRLEN
))
401 blobmsg_add_string(buf
, "ipv6", buffer
);
408 next
= avl_next_element(r
, avl
);
409 if (strcmp(r
->record
, next
->record
) != 0)
415 cache_dump_recursive(struct blob_buf
*b
, const char *name
, uint16_t type
, struct interface
*iface
)
417 time_t now
= monotonic_time();
418 for (struct cache_record
*r
= avl_find_ge_element(&records
, name
, r
, avl
);
419 r
&& !strcmp(r
->record
, name
);
420 r
= !avl_is_last(&records
, &r
->avl
) ? avl_next_element(r
, avl
) : NULL
) {
421 int32_t ttl
= r
->ttl
- (now
- r
->time
);
422 if (ttl
<= 0 || (iface
&& iface
->ifindex
!= r
->iface
->ifindex
) ||
423 (type
!= TYPE_ANY
&& type
!= r
->type
))
427 char buf
[INET6_ADDRSTRLEN
];
428 void *k
= blobmsg_open_table(b
, NULL
), *l
;
429 const struct dns_srv_data
*dsd
= (const struct dns_srv_data
*)r
->rdata
;
431 blobmsg_add_string(b
, "name", r
->record
);
432 blobmsg_add_string(b
, "type", dns_type_string(r
->type
));
433 blobmsg_add_u32(b
, "ttl", ttl
);
437 if ((txt
= r
->txt
) && strlen(txt
)) {
438 l
= blobmsg_open_array(b
, "data");
440 blobmsg_add_string(b
, NULL
, txt
);
441 txt
= &txt
[strlen(txt
) + 1];
443 blobmsg_close_array(b
, l
);
448 if (r
->rdlength
> sizeof(*dsd
)) {
449 blobmsg_add_u32(b
, "priority", be16_to_cpu(dsd
->priority
));
450 blobmsg_add_u32(b
, "weight", be16_to_cpu(dsd
->weight
));
451 blobmsg_add_u32(b
, "port", be16_to_cpu(dsd
->port
));
452 blobmsg_add_string(b
, "target", (const char*)&dsd
[1]);
458 blobmsg_add_string(b
, "target", (const char*)r
->rdata
);
462 if ((r
->rdlength
== 4) && inet_ntop(AF_INET
, r
->rdata
, buf
, sizeof(buf
)))
463 blobmsg_add_string(b
, "target", buf
);
467 if ((r
->rdlength
== 16) && inet_ntop(AF_INET6
, r
->rdata
, buf
, sizeof(buf
)))
468 blobmsg_add_string(b
, "target", buf
);
472 blobmsg_close_table(b
, k
);
475 if (r
->type
== TYPE_PTR
) {
476 cache_dump_recursive(b
, (const char*)r
->rdata
, TYPE_SRV
, iface
);
477 cache_dump_recursive(b
, (const char*)r
->rdata
, TYPE_TXT
, iface
);
480 if (r
->type
== TYPE_SRV
) {
481 cache_dump_recursive(b
, (const char*)&dsd
[1], TYPE_A
, iface
);
482 cache_dump_recursive(b
, (const char*)&dsd
[1], TYPE_AAAA
, iface
);