]>
git.ipfire.org Git - people/ms/dnsmasq.git/blob - src/forward.c
1 /* dnsmasq is Copyright (c) 2000-2013 Simon Kelley
3 This program is free software; you can redistribute it and/or modify
4 it under the terms of the GNU General Public License as published by
5 the Free Software Foundation; version 2 dated June, 1991, or
6 (at your option) version 3 dated 29 June, 2007.
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.
13 You should have received a copy of the GNU General Public License
14 along with this program. If not, see <http://www.gnu.org/licenses/>.
19 static struct frec
*lookup_frec(unsigned short id
, unsigned int crc
);
20 static struct frec
*lookup_frec_by_sender(unsigned short id
,
21 union mysockaddr
*addr
,
23 static unsigned short get_id(unsigned int crc
);
24 static void free_frec(struct frec
*f
);
25 static struct randfd
*allocate_rfd(int family
);
27 /* Send a UDP packet with its source address set as "source"
28 unless nowild is true, when we just send it with the kernel default */
29 int send_from(int fd
, int nowild
, char *packet
, size_t len
,
30 union mysockaddr
*to
, struct all_addr
*source
,
36 struct cmsghdr align
; /* this ensures alignment */
37 #if defined(HAVE_LINUX_NETWORK)
38 char control
[CMSG_SPACE(sizeof(struct in_pktinfo
))];
39 #elif defined(IP_SENDSRCADDR)
40 char control
[CMSG_SPACE(sizeof(struct in_addr
))];
43 char control6
[CMSG_SPACE(sizeof(struct in6_pktinfo
))];
47 iov
[0].iov_base
= packet
;
50 msg
.msg_control
= NULL
;
51 msg
.msg_controllen
= 0;
54 msg
.msg_namelen
= sa_len(to
);
60 struct cmsghdr
*cmptr
;
61 msg
.msg_control
= &control_u
;
62 msg
.msg_controllen
= sizeof(control_u
);
63 cmptr
= CMSG_FIRSTHDR(&msg
);
65 if (to
->sa
.sa_family
== AF_INET
)
67 #if defined(HAVE_LINUX_NETWORK)
70 p
.ipi_spec_dst
= source
->addr
.addr4
;
71 memcpy(CMSG_DATA(cmptr
), &p
, sizeof(p
));
72 msg
.msg_controllen
= cmptr
->cmsg_len
= CMSG_LEN(sizeof(struct in_pktinfo
));
73 cmptr
->cmsg_level
= IPPROTO_IP
;
74 cmptr
->cmsg_type
= IP_PKTINFO
;
75 #elif defined(IP_SENDSRCADDR)
76 memcpy(CMSG_DATA(cmptr
), &(source
->addr
.addr4
), sizeof(source
->addr
.addr4
));
77 msg
.msg_controllen
= cmptr
->cmsg_len
= CMSG_LEN(sizeof(struct in_addr
));
78 cmptr
->cmsg_level
= IPPROTO_IP
;
79 cmptr
->cmsg_type
= IP_SENDSRCADDR
;
86 p
.ipi6_ifindex
= iface
; /* Need iface for IPv6 to handle link-local addrs */
87 p
.ipi6_addr
= source
->addr
.addr6
;
88 memcpy(CMSG_DATA(cmptr
), &p
, sizeof(p
));
89 msg
.msg_controllen
= cmptr
->cmsg_len
= CMSG_LEN(sizeof(struct in6_pktinfo
));
90 cmptr
->cmsg_type
= daemon
->v6pktinfo
;
91 cmptr
->cmsg_level
= IPPROTO_IPV6
;
94 (void)iface
; /* eliminate warning */
98 while (sendmsg(fd
, &msg
, 0) == -1)
103 /* If interface is still in DAD, EINVAL results - ignore that. */
107 my_syslog(LOG_ERR
, _("failed to send packet: %s"), strerror(errno
));
114 static unsigned int search_servers(time_t now
, struct all_addr
**addrpp
,
115 unsigned int qtype
, char *qdomain
, int *type
, char **domain
, int *norebind
)
118 /* If the query ends in the domain in one of our servers, set
119 domain to point to that name. We find the largest match to allow both
120 domain.org and sub.domain.org to exist. */
122 unsigned int namelen
= strlen(qdomain
);
123 unsigned int matchlen
= 0;
125 unsigned int flags
= 0;
127 for (serv
= daemon
->servers
; serv
; serv
=serv
->next
)
128 /* domain matches take priority over NODOTS matches */
129 if ((serv
->flags
& SERV_FOR_NODOTS
) && *type
!= SERV_HAS_DOMAIN
&& !strchr(qdomain
, '.') && namelen
!= 0)
131 unsigned int sflag
= serv
->addr
.sa
.sa_family
== AF_INET
? F_IPV4
: F_IPV6
;
132 *type
= SERV_FOR_NODOTS
;
133 if (serv
->flags
& SERV_NO_ADDR
)
135 else if (serv
->flags
& SERV_LITERAL_ADDRESS
)
140 if (serv
->addr
.sa
.sa_family
== AF_INET
)
141 *addrpp
= (struct all_addr
*)&serv
->addr
.in
.sin_addr
;
144 *addrpp
= (struct all_addr
*)&serv
->addr
.in6
.sin6_addr
;
147 else if (!flags
|| (flags
& F_NXDOMAIN
))
151 else if (serv
->flags
& SERV_HAS_DOMAIN
)
153 unsigned int domainlen
= strlen(serv
->domain
);
154 char *matchstart
= qdomain
+ namelen
- domainlen
;
155 if (namelen
>= domainlen
&&
156 hostname_isequal(matchstart
, serv
->domain
) &&
157 (domainlen
== 0 || namelen
== domainlen
|| *(matchstart
-1) == '.' ))
159 if (serv
->flags
& SERV_NO_REBIND
)
163 unsigned int sflag
= serv
->addr
.sa
.sa_family
== AF_INET
? F_IPV4
: F_IPV6
;
164 /* implement priority rules for --address and --server for same domain.
165 --address wins if the address is for the correct AF
166 --server wins otherwise. */
167 if (domainlen
!= 0 && domainlen
== matchlen
)
169 if ((serv
->flags
& SERV_LITERAL_ADDRESS
))
171 if (!(sflag
& qtype
) && flags
== 0)
176 if (flags
& (F_IPV4
| F_IPV6
))
181 if (domainlen
>= matchlen
)
183 *type
= serv
->flags
& (SERV_HAS_DOMAIN
| SERV_USE_RESOLV
| SERV_NO_REBIND
);
184 *domain
= serv
->domain
;
185 matchlen
= domainlen
;
186 if (serv
->flags
& SERV_NO_ADDR
)
188 else if (serv
->flags
& SERV_LITERAL_ADDRESS
)
193 if (serv
->addr
.sa
.sa_family
== AF_INET
)
194 *addrpp
= (struct all_addr
*)&serv
->addr
.in
.sin_addr
;
197 *addrpp
= (struct all_addr
*)&serv
->addr
.in6
.sin6_addr
;
200 else if (!flags
|| (flags
& F_NXDOMAIN
))
210 if (flags
== 0 && !(qtype
& F_QUERY
) &&
211 option_bool(OPT_NODOTS_LOCAL
) && !strchr(qdomain
, '.') && namelen
!= 0)
212 /* don't forward A or AAAA queries for simple names, except the empty name */
215 if (flags
== F_NXDOMAIN
&& check_for_local_domain(qdomain
, now
))
222 if (flags
== F_NXDOMAIN
|| flags
== F_NOERR
)
223 logflags
= F_NEG
| qtype
;
225 log_query(logflags
| flags
| F_CONFIG
| F_FORWARD
, qdomain
, *addrpp
, NULL
);
227 else if ((*type
) & SERV_USE_RESOLV
)
229 *type
= 0; /* use normal servers for this domain */
235 static int forward_query(int udpfd
, union mysockaddr
*udpaddr
,
236 struct all_addr
*dst_addr
, unsigned int dst_iface
,
237 struct dns_header
*header
, size_t plen
, time_t now
, struct frec
*forward
)
240 int type
= 0, norebind
= 0;
241 struct all_addr
*addrp
= NULL
;
242 unsigned int crc
= questions_crc(header
, plen
, daemon
->namebuff
);
243 unsigned int flags
= 0;
244 unsigned int gotname
= extract_request(header
, plen
, daemon
->namebuff
, NULL
);
245 struct server
*start
= NULL
;
247 /* RFC 4035: sect 4.6 para 2 */
248 header
->hb4
&= ~HB4_AD
;
250 /* may be no servers available. */
251 if (!daemon
->servers
)
253 else if (forward
|| (forward
= lookup_frec_by_sender(ntohs(header
->id
), udpaddr
, crc
)))
255 /* retry on existing query, send to all available servers */
256 domain
= forward
->sentto
->domain
;
257 forward
->sentto
->failed_queries
++;
258 if (!option_bool(OPT_ORDER
))
260 forward
->forwardall
= 1;
261 daemon
->last_server
= NULL
;
263 type
= forward
->sentto
->flags
& SERV_TYPE
;
264 if (!(start
= forward
->sentto
->next
))
265 start
= daemon
->servers
; /* at end of list, recycle */
266 header
->id
= htons(forward
->new_id
);
271 flags
= search_servers(now
, &addrp
, gotname
, daemon
->namebuff
, &type
, &domain
, &norebind
);
273 if (!flags
&& !(forward
= get_new_frec(now
, NULL
, 0)))
274 /* table full - server failure. */
279 forward
->source
= *udpaddr
;
280 forward
->dest
= *dst_addr
;
281 forward
->iface
= dst_iface
;
282 forward
->orig_id
= ntohs(header
->id
);
283 forward
->new_id
= get_id(crc
);
286 forward
->forwardall
= 0;
289 forward
->flags
|= FREC_NOREBIND
;
290 if (header
->hb4
& HB4_CD
)
291 forward
->flags
|= FREC_CHECKING_DISABLED
;
293 header
->id
= htons(forward
->new_id
);
295 /* In strict_order mode, always try servers in the order
296 specified in resolv.conf, if a domain is given
297 always try all the available servers,
298 otherwise, use the one last known to work. */
302 if (option_bool(OPT_ORDER
))
303 start
= daemon
->servers
;
304 else if (!(start
= daemon
->last_server
) ||
305 daemon
->forwardcount
++ > FORWARD_TEST
||
306 difftime(now
, daemon
->forwardtime
) > FORWARD_TIME
)
308 start
= daemon
->servers
;
309 forward
->forwardall
= 1;
310 daemon
->forwardcount
= 0;
311 daemon
->forwardtime
= now
;
316 start
= daemon
->servers
;
317 if (!option_bool(OPT_ORDER
))
318 forward
->forwardall
= 1;
323 /* check for send errors here (no route to host)
324 if we fail to send to all nameservers, send back an error
325 packet straight away (helps modem users when offline) */
327 if (!flags
&& forward
)
329 struct server
*firstsentto
= start
;
332 if (option_bool(OPT_ADD_MAC
))
333 plen
= add_mac(header
, plen
, ((char *) header
) + PACKETSZ
, &forward
->source
);
335 if (option_bool(OPT_CLIENT_SUBNET
))
337 size_t new = add_source_addr(header
, plen
, ((char *) header
) + PACKETSZ
, &forward
->source
);
341 forward
->flags
|= FREC_HAS_SUBNET
;
346 if (option_bool(OPT_DNSSEC_VALID
))
348 plen
= add_do_bit(header
, plen
, ((char *) header
) + PACKETSZ
);
349 header
->hb4
|= HB4_CD
;
355 /* only send to servers dealing with our domain.
356 domain may be NULL, in which case server->domain
357 must be NULL also. */
359 if (type
== (start
->flags
& SERV_TYPE
) &&
360 (type
!= SERV_HAS_DOMAIN
|| hostname_isequal(domain
, start
->domain
)) &&
361 !(start
->flags
& SERV_LITERAL_ADDRESS
))
365 /* find server socket to use, may need to get random one. */
371 if (start
->addr
.sa
.sa_family
== AF_INET6
)
373 if (!forward
->rfd6
&&
374 !(forward
->rfd6
= allocate_rfd(AF_INET6
)))
376 daemon
->rfd_save
= forward
->rfd6
;
377 fd
= forward
->rfd6
->fd
;
382 if (!forward
->rfd4
&&
383 !(forward
->rfd4
= allocate_rfd(AF_INET
)))
385 daemon
->rfd_save
= forward
->rfd4
;
386 fd
= forward
->rfd4
->fd
;
389 #ifdef HAVE_CONNTRACK
390 /* Copy connection mark of incoming query to outgoing connection. */
391 if (option_bool(OPT_CONNTRACK
))
394 if (get_incoming_mark(&forward
->source
, &forward
->dest
, 0, &mark
))
395 setsockopt(fd
, SOL_SOCKET
, SO_MARK
, &mark
, sizeof(unsigned int));
400 if (sendto(fd
, (char *)header
, plen
, 0,
402 sa_len(&start
->addr
)) == -1)
409 /* Keep info in case we want to re-send this packet */
410 daemon
->srv_save
= start
;
411 daemon
->packet_len
= plen
;
414 strcpy(daemon
->namebuff
, "query");
415 if (start
->addr
.sa
.sa_family
== AF_INET
)
416 log_query(F_SERVER
| F_IPV4
| F_FORWARD
, daemon
->namebuff
,
417 (struct all_addr
*)&start
->addr
.in
.sin_addr
, NULL
);
420 log_query(F_SERVER
| F_IPV6
| F_FORWARD
, daemon
->namebuff
,
421 (struct all_addr
*)&start
->addr
.in6
.sin6_addr
, NULL
);
425 forward
->sentto
= start
;
426 if (!forward
->forwardall
)
428 forward
->forwardall
++;
432 if (!(start
= start
->next
))
433 start
= daemon
->servers
;
435 if (start
== firstsentto
)
442 /* could not send on, prepare to return */
443 header
->id
= htons(forward
->orig_id
);
444 free_frec(forward
); /* cancel */
447 /* could not send on, return empty answer or address if known for whole domain */
450 plen
= setup_reply(header
, plen
, addrp
, flags
, daemon
->local_ttl
);
451 send_from(udpfd
, option_bool(OPT_NOWILD
) || option_bool(OPT_CLEVERBIND
), (char *)header
, plen
, udpaddr
, dst_addr
, dst_iface
);
457 static size_t process_reply(struct dns_header
*header
, time_t now
, struct server
*server
, size_t n
, int check_rebind
,
458 int no_cache
, int cache_secure
, int check_subnet
, union mysockaddr
*query_source
)
460 unsigned char *pheader
, *sizep
;
462 int munged
= 0, is_sign
;
467 /* Similar algorithm to search_servers. */
468 struct ipsets
*ipset_pos
;
469 unsigned int namelen
= strlen(daemon
->namebuff
);
470 unsigned int matchlen
= 0;
471 for (ipset_pos
= daemon
->ipsets
; ipset_pos
; ipset_pos
= ipset_pos
->next
)
473 unsigned int domainlen
= strlen(ipset_pos
->domain
);
474 char *matchstart
= daemon
->namebuff
+ namelen
- domainlen
;
475 if (namelen
>= domainlen
&& hostname_isequal(matchstart
, ipset_pos
->domain
) &&
476 (domainlen
== 0 || namelen
== domainlen
|| *(matchstart
- 1) == '.' ) &&
477 domainlen
>= matchlen
) {
478 matchlen
= domainlen
;
479 sets
= ipset_pos
->sets
;
484 /* If upstream is advertising a larger UDP packet size
485 than we allow, trim it so that we don't get overlarge
486 requests for the client. We can't do this for signed packets. */
488 if ((pheader
= find_pseudoheader(header
, n
, &plen
, &sizep
, &is_sign
)))
492 unsigned short udpsz
;
493 unsigned char *psave
= sizep
;
495 GETSHORT(udpsz
, sizep
);
496 if (udpsz
> daemon
->edns_pktsz
)
497 PUTSHORT(daemon
->edns_pktsz
, psave
);
500 if (check_subnet
&& !check_source(header
, plen
, pheader
, query_source
))
502 my_syslog(LOG_WARNING
, _("discarding DNS reply: subnet option mismatch"));
507 /* RFC 4035 sect 4.6 para 3 */
508 if (!is_sign
&& !option_bool(OPT_DNSSEC_PROXY
))
512 if (option_bool(OPT_DNSSEC_VALID
))
513 squash_ad
= no_cache
;
516 header
->hb4
|= HB4_AD
;
520 header
->hb4
&= ~HB4_AD
;
522 if (OPCODE(header
) != QUERY
|| (RCODE(header
) != NOERROR
&& RCODE(header
) != NXDOMAIN
))
525 /* Complain loudly if the upstream server is non-recursive. */
526 if (!(header
->hb4
& HB4_RA
) && RCODE(header
) == NOERROR
&& ntohs(header
->ancount
) == 0 &&
527 server
&& !(server
->flags
& SERV_WARNED_RECURSIVE
))
529 prettyprint_addr(&server
->addr
, daemon
->namebuff
);
530 my_syslog(LOG_WARNING
, _("nameserver %s refused to do a recursive query"), daemon
->namebuff
);
531 if (!option_bool(OPT_LOG
))
532 server
->flags
|= SERV_WARNED_RECURSIVE
;
535 if (daemon
->bogus_addr
&& RCODE(header
) != NXDOMAIN
&&
536 check_for_bogus_wildcard(header
, n
, daemon
->namebuff
, daemon
->bogus_addr
, now
))
539 SET_RCODE(header
, NXDOMAIN
);
540 header
->hb3
&= ~HB3_AA
;
544 if (RCODE(header
) == NXDOMAIN
&&
545 extract_request(header
, n
, daemon
->namebuff
, NULL
) &&
546 check_for_local_domain(daemon
->namebuff
, now
))
548 /* if we forwarded a query for a locally known name (because it was for
549 an unknown type) and the answer is NXDOMAIN, convert that to NODATA,
550 since we know that the domain exists, even if upstream doesn't */
552 header
->hb3
|= HB3_AA
;
553 SET_RCODE(header
, NOERROR
);
556 if (extract_addresses(header
, n
, daemon
->namebuff
, now
, sets
, is_sign
, check_rebind
, no_cache
, cache_secure
))
558 my_syslog(LOG_WARNING
, _("possible DNS-rebind attack detected: %s"), daemon
->namebuff
);
563 /* do this after extract_addresses. Ensure NODATA reply and remove
568 header
->ancount
= htons(0);
569 header
->nscount
= htons(0);
570 header
->arcount
= htons(0);
573 /* the bogus-nxdomain stuff, doctor and NXDOMAIN->NODATA munging can all elide
574 sections of the packet. Find the new length here and put back pseudoheader
575 if it was removed. */
576 return resize_packet(header
, n
, pheader
, plen
);
579 /* sets new last_server */
580 void reply_query(int fd
, int family
, time_t now
)
582 /* packet from peer server, extract data for cache, and send to
583 original requester */
584 struct dns_header
*header
;
585 union mysockaddr serveraddr
;
586 struct frec
*forward
;
587 socklen_t addrlen
= sizeof(serveraddr
);
588 ssize_t n
= recvfrom(fd
, daemon
->packet
, daemon
->edns_pktsz
, 0, &serveraddr
.sa
, &addrlen
);
590 struct server
*server
;
592 /* packet buffer overwritten */
593 daemon
->srv_save
= NULL
;
595 /* Determine the address of the server replying so that we can mark that as good */
596 serveraddr
.sa
.sa_family
= family
;
598 if (serveraddr
.sa
.sa_family
== AF_INET6
)
599 serveraddr
.in6
.sin6_flowinfo
= 0;
602 /* spoof check: answer must come from known server, */
603 for (server
= daemon
->servers
; server
; server
= server
->next
)
604 if (!(server
->flags
& (SERV_LITERAL_ADDRESS
| SERV_NO_ADDR
)) &&
605 sockaddr_isequal(&server
->addr
, &serveraddr
))
608 header
= (struct dns_header
*)daemon
->packet
;
611 n
< (int)sizeof(struct dns_header
) || !(header
->hb3
& HB3_QR
) ||
612 !(forward
= lookup_frec(ntohs(header
->id
), questions_crc(header
, n
, daemon
->namebuff
))))
615 if ((RCODE(header
) == SERVFAIL
|| RCODE(header
) == REFUSED
) &&
616 !option_bool(OPT_ORDER
) &&
617 forward
->forwardall
== 0)
618 /* for broken servers, attempt to send to another one. */
620 unsigned char *pheader
;
624 /* recreate query from reply */
625 pheader
= find_pseudoheader(header
, (size_t)n
, &plen
, NULL
, &is_sign
);
628 header
->ancount
= htons(0);
629 header
->nscount
= htons(0);
630 header
->arcount
= htons(0);
631 if ((nn
= resize_packet(header
, (size_t)n
, pheader
, plen
)))
633 header
->hb3
&= ~(HB3_QR
| HB3_TC
);
634 forward_query(-1, NULL
, NULL
, 0, header
, nn
, now
, forward
);
640 server
= forward
->sentto
;
642 if ((forward
->sentto
->flags
& SERV_TYPE
) == 0)
644 if (RCODE(header
) == SERVFAIL
|| RCODE(header
) == REFUSED
)
648 struct server
*last_server
;
650 /* find good server by address if possible, otherwise assume the last one we sent to */
651 for (last_server
= daemon
->servers
; last_server
; last_server
= last_server
->next
)
652 if (!(last_server
->flags
& (SERV_LITERAL_ADDRESS
| SERV_HAS_DOMAIN
| SERV_FOR_NODOTS
| SERV_NO_ADDR
)) &&
653 sockaddr_isequal(&last_server
->addr
, &serveraddr
))
655 server
= last_server
;
659 if (!option_bool(OPT_ALL_SERVERS
))
660 daemon
->last_server
= server
;
663 /* If the answer is an error, keep the forward record in place in case
664 we get a good reply from another server. Kill it when we've
665 had replies from all to avoid filling the forwarding table when
666 everything is broken */
667 if (forward
->forwardall
== 0 || --forward
->forwardall
== 1 ||
668 (RCODE(header
) != REFUSED
&& RCODE(header
) != SERVFAIL
))
670 int check_rebind
= 0, no_cache_dnssec
= 0, cache_secure
= 0;
672 if (option_bool(OPT_NO_REBIND
))
673 check_rebind
= !(forward
->flags
& FREC_NOREBIND
);
675 /* Don't cache replies where DNSSEC validation was turned off, either
676 the upstream server told us so, or the original query specified it. */
677 if ((header
->hb4
& HB4_CD
) || (forward
->flags
& FREC_CHECKING_DISABLED
))
681 if (option_bool(OPT_DNSSEC_VALID
) && !(forward
->flags
& FREC_CHECKING_DISABLED
))
685 /* We've had a reply already, which we're validating. Ignore this duplicate */
689 if (header
->hb3
& HB3_TC
)
691 /* Truncated answer can't be validated.
692 The client will retry over TCP, but if this is an answer to a
693 DNSSEC-generated query, we have a problem. Should really re-send
694 over TCP. No-one with any sense will make a DNSKEY or DS RRset
695 exceed 4096, so this may not be a real problem. Just log
697 if (forward
->flags
& (FREC_DNSKEY_QUERY
| FREC_DS_QUERY
))
698 my_syslog(LOG_ERR
, _("Reply to DNSSEC query truncated - validation fails."));
699 status
= STAT_INSECURE
;
701 else if (forward
->flags
& FREC_DNSKEY_QUERY
)
702 status
= dnssec_validate_by_ds(now
, header
, n
, daemon
->namebuff
, daemon
->keyname
, forward
->class);
703 else if (forward
->flags
& FREC_DS_QUERY
)
704 status
= dnssec_validate_ds(now
, header
, n
, daemon
->namebuff
, daemon
->keyname
, forward
->class);
706 status
= dnssec_validate_reply(now
, header
, n
, daemon
->namebuff
, daemon
->keyname
, &forward
->class);
708 /* Can't validate, as we're missing key data. Put this
709 answer aside, whilst we get that. */
710 if (status
== STAT_NEED_DS
|| status
== STAT_NEED_KEY
)
714 if ((new = get_new_frec(now
, NULL
, 1)))
716 struct frec
*next
= new->next
;
717 *new = *forward
; /* copy everything, then overwrite */
720 new->blocking_query
= NULL
;
721 new->flags
&= ~(FREC_DNSKEY_QUERY
| FREC_DS_QUERY
);
723 if ((forward
->stash
= blockdata_alloc((char *)header
, n
)))
727 forward
->stash_len
= n
;
729 new->dependent
= forward
; /* to find query awaiting new one. */
730 forward
->blocking_query
= new; /* for garbage cleaning */
731 /* validate routines leave name of required record in daemon->keyname */
732 if (status
== STAT_NEED_KEY
)
734 new->flags
|= FREC_DNSKEY_QUERY
;
735 nn
= dnssec_generate_query(header
, daemon
->keyname
, forward
->class, T_DNSKEY
, &server
->addr
);
737 else if (status
== STAT_NEED_DS
)
739 new->flags
|= FREC_DS_QUERY
;
740 nn
= dnssec_generate_query(header
, daemon
->keyname
, forward
->class, T_DS
, &server
->addr
);
742 new->crc
= questions_crc(header
, nn
, daemon
->namebuff
);
743 new->new_id
= get_id(new->crc
);
744 header
->id
= htons(new->new_id
);
746 /* Don't resend this. */
747 daemon
->srv_save
= NULL
;
750 fd
= server
->sfd
->fd
;
753 /* Note that we use the same random port for the DNSSEC stuff */
754 if (server
->addr
.sa
.sa_family
== AF_INET6
)
757 new->rfd6
->refcount
++;
763 new->rfd4
->refcount
++;
766 /* Send DNSSEC query to same server as original query */
767 while (sendto(fd
, (char *)header
, nn
, 0, &server
->addr
.sa
, sa_len(&server
->addr
)) == -1 && retry_send());
775 /* Ok, we reached far enough up the chain-of-trust that we can validate something.
776 Now wind back down, pulling back answers which wouldn't previously validate
777 and validate them with the new data. Failure to find needed data here is an internal error.
778 Once we get to the original answer (FREC_DNSSEC_QUERY not set) and it validates,
779 return it to the original requestor. */
780 if (forward
->flags
& (FREC_DNSKEY_QUERY
| FREC_DS_QUERY
))
782 while (forward
->dependent
)
786 if (status
== STAT_SECURE
)
788 if (forward
->flags
& FREC_DNSKEY_QUERY
)
789 status
= dnssec_validate_by_ds(now
, header
, n
, daemon
->namebuff
, daemon
->keyname
, forward
->class);
790 else if (forward
->flags
& FREC_DS_QUERY
)
791 status
= dnssec_validate_ds(now
, header
, n
, daemon
->namebuff
, daemon
->keyname
, forward
->class);
794 prev
= forward
->dependent
;
797 forward
->blocking_query
= NULL
; /* already gone */
798 blockdata_retrieve(forward
->stash
, forward
->stash_len
, (void *)header
);
799 n
= forward
->stash_len
;
802 /* All DNSKEY and DS records done and in cache, now finally validate original
803 answer, provided last DNSKEY is OK. */
804 if (status
== STAT_SECURE
)
805 status
= dnssec_validate_reply(now
, header
, n
, daemon
->namebuff
, daemon
->keyname
, &forward
->class);
807 if (status
== STAT_NEED_DS
|| status
== STAT_NEED_KEY
)
809 my_syslog(LOG_ERR
, _("Unexpected missing data for DNSSEC validation"));
810 status
= STAT_INSECURE
;
814 log_query(F_KEYTAG
| F_SECSTAT
, "result", NULL
,
815 status
== STAT_SECURE
? "SECURE" : (status
== STAT_INSECURE
? "INSECURE" : "BOGUS"));
819 if (status
== STAT_SECURE
)
821 /* TODO return SERVFAIL here */
822 else if (status
== STAT_BOGUS
)
825 /* restore CD bit to the value in the query */
826 if (forward
->flags
& FREC_CHECKING_DISABLED
)
827 header
->hb4
|= HB4_CD
;
829 header
->hb4
&= ~HB4_CD
;
833 if ((nn
= process_reply(header
, now
, server
, (size_t)n
, check_rebind
, no_cache_dnssec
, cache_secure
,
834 forward
->flags
& FREC_HAS_SUBNET
, &forward
->source
)))
836 header
->id
= htons(forward
->orig_id
);
837 header
->hb4
|= HB4_RA
; /* recursion if available */
838 send_from(forward
->fd
, option_bool(OPT_NOWILD
) || option_bool (OPT_CLEVERBIND
), daemon
->packet
, nn
,
839 &forward
->source
, &forward
->dest
, forward
->iface
);
841 free_frec(forward
); /* cancel */
846 void receive_query(struct listener
*listen
, time_t now
)
848 struct dns_header
*header
= (struct dns_header
*)daemon
->packet
;
849 union mysockaddr source_addr
;
851 struct all_addr dst_addr
;
852 struct in_addr netmask
, dst_addr_4
;
855 int if_index
= 0, auth_dns
= 0;
861 struct cmsghdr
*cmptr
;
863 struct cmsghdr align
; /* this ensures alignment */
865 char control6
[CMSG_SPACE(sizeof(struct in6_pktinfo
))];
867 #if defined(HAVE_LINUX_NETWORK)
868 char control
[CMSG_SPACE(sizeof(struct in_pktinfo
))];
869 #elif defined(IP_RECVDSTADDR) && defined(HAVE_SOLARIS_NETWORK)
870 char control
[CMSG_SPACE(sizeof(struct in_addr
)) +
871 CMSG_SPACE(sizeof(unsigned int))];
872 #elif defined(IP_RECVDSTADDR)
873 char control
[CMSG_SPACE(sizeof(struct in_addr
)) +
874 CMSG_SPACE(sizeof(struct sockaddr_dl
))];
878 /* Can always get recvd interface for IPv6 */
879 int check_dst
= !option_bool(OPT_NOWILD
) || listen
->family
== AF_INET6
;
881 int check_dst
= !option_bool(OPT_NOWILD
);
884 /* packet buffer overwritten */
885 daemon
->srv_save
= NULL
;
887 dst_addr_4
.s_addr
= 0;
890 if (option_bool(OPT_NOWILD
) && listen
->iface
)
892 auth_dns
= listen
->iface
->dns_auth
;
894 if (listen
->family
== AF_INET
)
896 dst_addr_4
= listen
->iface
->addr
.in
.sin_addr
;
897 netmask
= listen
->iface
->netmask
;
901 iov
[0].iov_base
= daemon
->packet
;
902 iov
[0].iov_len
= daemon
->edns_pktsz
;
904 msg
.msg_control
= control_u
.control
;
905 msg
.msg_controllen
= sizeof(control_u
);
907 msg
.msg_name
= &source_addr
;
908 msg
.msg_namelen
= sizeof(source_addr
);
912 if ((n
= recvmsg(listen
->fd
, &msg
, 0)) == -1)
915 if (n
< (int)sizeof(struct dns_header
) ||
916 (msg
.msg_flags
& MSG_TRUNC
) ||
917 (header
->hb3
& HB3_QR
))
920 source_addr
.sa
.sa_family
= listen
->family
;
922 if (listen
->family
== AF_INET6
)
923 source_addr
.in6
.sin6_flowinfo
= 0;
930 if (msg
.msg_controllen
< sizeof(struct cmsghdr
))
933 #if defined(HAVE_LINUX_NETWORK)
934 if (listen
->family
== AF_INET
)
935 for (cmptr
= CMSG_FIRSTHDR(&msg
); cmptr
; cmptr
= CMSG_NXTHDR(&msg
, cmptr
))
936 if (cmptr
->cmsg_level
== IPPROTO_IP
&& cmptr
->cmsg_type
== IP_PKTINFO
)
940 struct in_pktinfo
*p
;
942 p
.c
= CMSG_DATA(cmptr
);
943 dst_addr_4
= dst_addr
.addr
.addr4
= p
.p
->ipi_spec_dst
;
944 if_index
= p
.p
->ipi_ifindex
;
946 #elif defined(IP_RECVDSTADDR) && defined(IP_RECVIF)
947 if (listen
->family
== AF_INET
)
949 for (cmptr
= CMSG_FIRSTHDR(&msg
); cmptr
; cmptr
= CMSG_NXTHDR(&msg
, cmptr
))
955 #ifndef HAVE_SOLARIS_NETWORK
956 struct sockaddr_dl
*s
;
959 p
.c
= CMSG_DATA(cmptr
);
960 if (cmptr
->cmsg_level
== IPPROTO_IP
&& cmptr
->cmsg_type
== IP_RECVDSTADDR
)
961 dst_addr_4
= dst_addr
.addr
.addr4
= *(p
.a
);
962 else if (cmptr
->cmsg_level
== IPPROTO_IP
&& cmptr
->cmsg_type
== IP_RECVIF
)
963 #ifdef HAVE_SOLARIS_NETWORK
966 if_index
= p
.s
->sdl_index
;
973 if (listen
->family
== AF_INET6
)
975 for (cmptr
= CMSG_FIRSTHDR(&msg
); cmptr
; cmptr
= CMSG_NXTHDR(&msg
, cmptr
))
976 if (cmptr
->cmsg_level
== IPPROTO_IPV6
&& cmptr
->cmsg_type
== daemon
->v6pktinfo
)
980 struct in6_pktinfo
*p
;
982 p
.c
= CMSG_DATA(cmptr
);
984 dst_addr
.addr
.addr6
= p
.p
->ipi6_addr
;
985 if_index
= p
.p
->ipi6_ifindex
;
990 /* enforce available interface configuration */
992 if (!indextoname(listen
->fd
, if_index
, ifr
.ifr_name
))
995 if (!iface_check(listen
->family
, &dst_addr
, ifr
.ifr_name
, &auth_dns
))
997 if (!option_bool(OPT_CLEVERBIND
))
998 enumerate_interfaces(0);
999 if (!loopback_exception(listen
->fd
, listen
->family
, &dst_addr
, ifr
.ifr_name
) &&
1000 !label_exception(if_index
, listen
->family
, &dst_addr
))
1004 if (listen
->family
== AF_INET
&& option_bool(OPT_LOCALISE
))
1008 /* get the netmask of the interface whch has the address we were sent to.
1009 This is no neccessarily the interface we arrived on. */
1011 for (iface
= daemon
->interfaces
; iface
; iface
= iface
->next
)
1012 if (iface
->addr
.sa
.sa_family
== AF_INET
&&
1013 iface
->addr
.in
.sin_addr
.s_addr
== dst_addr_4
.s_addr
)
1016 /* interface may be new */
1017 if (!iface
&& !option_bool(OPT_CLEVERBIND
))
1018 enumerate_interfaces(0);
1020 for (iface
= daemon
->interfaces
; iface
; iface
= iface
->next
)
1021 if (iface
->addr
.sa
.sa_family
== AF_INET
&&
1022 iface
->addr
.in
.sin_addr
.s_addr
== dst_addr_4
.s_addr
)
1025 /* If we failed, abandon localisation */
1027 netmask
= iface
->netmask
;
1029 dst_addr_4
.s_addr
= 0;
1033 if (extract_request(header
, (size_t)n
, daemon
->namebuff
, &type
))
1037 struct auth_zone
*zone
;
1040 querystr(auth_dns
? "auth" : "query", types
, type
);
1042 if (listen
->family
== AF_INET
)
1043 log_query(F_QUERY
| F_IPV4
| F_FORWARD
, daemon
->namebuff
,
1044 (struct all_addr
*)&source_addr
.in
.sin_addr
, types
);
1047 log_query(F_QUERY
| F_IPV6
| F_FORWARD
, daemon
->namebuff
,
1048 (struct all_addr
*)&source_addr
.in6
.sin6_addr
, types
);
1052 /* find queries for zones we're authoritative for, and answer them directly */
1054 for (zone
= daemon
->auth_zones
; zone
; zone
= zone
->next
)
1055 if (in_zone(zone
, daemon
->namebuff
, NULL
))
1067 m
= answer_auth(header
, ((char *) header
) + PACKETSZ
, (size_t)n
, now
, &source_addr
, local_auth
);
1070 send_from(listen
->fd
, option_bool(OPT_NOWILD
) || option_bool(OPT_CLEVERBIND
),
1071 (char *)header
, m
, &source_addr
, &dst_addr
, if_index
);
1072 daemon
->auth_answer
++;
1078 m
= answer_request(header
, ((char *) header
) + PACKETSZ
, (size_t)n
,
1079 dst_addr_4
, netmask
, now
);
1083 send_from(listen
->fd
, option_bool(OPT_NOWILD
) || option_bool(OPT_CLEVERBIND
),
1084 (char *)header
, m
, &source_addr
, &dst_addr
, if_index
);
1085 daemon
->local_answer
++;
1087 else if (forward_query(listen
->fd
, &source_addr
, &dst_addr
, if_index
,
1088 header
, (size_t)n
, now
, NULL
))
1089 daemon
->queries_forwarded
++;
1091 daemon
->local_answer
++;
1095 /* The daemon forks before calling this: it should deal with one connection,
1096 blocking as neccessary, and then return. Note, need to be a bit careful
1097 about resources for debug mode, when the fork is suppressed: that's
1098 done by the caller. */
1099 unsigned char *tcp_request(int confd
, time_t now
,
1100 union mysockaddr
*local_addr
, struct in_addr netmask
, int auth_dns
)
1107 int checking_disabled
, check_subnet
;
1109 unsigned short qtype
;
1110 unsigned int gotname
;
1111 unsigned char c1
, c2
;
1112 /* Max TCP packet + slop + size */
1113 unsigned char *packet
= whine_malloc(65536 + MAXDNAME
+ RRFIXEDSZ
+ sizeof(u16
));
1114 unsigned char *payload
= &packet
[2];
1115 /* largest field in header is 16-bits, so this is still sufficiently aligned */
1116 struct dns_header
*header
= (struct dns_header
*)payload
;
1117 u16
*length
= (u16
*)packet
;
1118 struct server
*last_server
;
1119 struct in_addr dst_addr_4
;
1120 union mysockaddr peer_addr
;
1121 socklen_t peer_len
= sizeof(union mysockaddr
);
1123 if (getpeername(confd
, (struct sockaddr
*)&peer_addr
, &peer_len
) == -1)
1129 !read_write(confd
, &c1
, 1, 1) || !read_write(confd
, &c2
, 1, 1) ||
1130 !(size
= c1
<< 8 | c2
) ||
1131 !read_write(confd
, payload
, size
, 1))
1134 if (size
< (int)sizeof(struct dns_header
))
1139 /* save state of "cd" flag in query */
1140 checking_disabled
= header
->hb4
& HB4_CD
;
1142 /* RFC 4035: sect 4.6 para 2 */
1143 header
->hb4
&= ~HB4_AD
;
1145 if ((gotname
= extract_request(header
, (unsigned int)size
, daemon
->namebuff
, &qtype
)))
1149 struct auth_zone
*zone
;
1151 querystr(auth_dns
? "auth" : "query", types
, qtype
);
1153 if (peer_addr
.sa
.sa_family
== AF_INET
)
1154 log_query(F_QUERY
| F_IPV4
| F_FORWARD
, daemon
->namebuff
,
1155 (struct all_addr
*)&peer_addr
.in
.sin_addr
, types
);
1158 log_query(F_QUERY
| F_IPV6
| F_FORWARD
, daemon
->namebuff
,
1159 (struct all_addr
*)&peer_addr
.in6
.sin6_addr
, types
);
1163 /* find queries for zones we're authoritative for, and answer them directly */
1165 for (zone
= daemon
->auth_zones
; zone
; zone
= zone
->next
)
1166 if (in_zone(zone
, daemon
->namebuff
, NULL
))
1175 if (local_addr
->sa
.sa_family
== AF_INET
)
1176 dst_addr_4
= local_addr
->in
.sin_addr
;
1178 dst_addr_4
.s_addr
= 0;
1182 m
= answer_auth(header
, ((char *) header
) + 65536, (size_t)size
, now
, &peer_addr
, local_auth
);
1186 /* m > 0 if answered from cache */
1187 m
= answer_request(header
, ((char *) header
) + 65536, (size_t)size
,
1188 dst_addr_4
, netmask
, now
);
1190 /* Do this by steam now we're not in the select() loop */
1191 check_log_writer(NULL
);
1195 unsigned int flags
= 0;
1196 struct all_addr
*addrp
= NULL
;
1198 char *domain
= NULL
;
1200 if (option_bool(OPT_ADD_MAC
))
1201 size
= add_mac(header
, size
, ((char *) header
) + 65536, &peer_addr
);
1203 if (option_bool(OPT_CLIENT_SUBNET
))
1205 size_t new = add_source_addr(header
, size
, ((char *) header
) + 65536, &peer_addr
);
1214 flags
= search_servers(now
, &addrp
, gotname
, daemon
->namebuff
, &type
, &domain
, &norebind
);
1216 if (type
!= 0 || option_bool(OPT_ORDER
) || !daemon
->last_server
)
1217 last_server
= daemon
->servers
;
1219 last_server
= daemon
->last_server
;
1221 if (!flags
&& last_server
)
1223 struct server
*firstsendto
= NULL
;
1224 unsigned int crc
= questions_crc(header
, (unsigned int)size
, daemon
->namebuff
);
1226 /* Loop round available servers until we succeed in connecting to one.
1227 Note that this code subtley ensures that consecutive queries on this connection
1228 which can go to the same server, do so. */
1232 firstsendto
= last_server
;
1235 if (!(last_server
= last_server
->next
))
1236 last_server
= daemon
->servers
;
1238 if (last_server
== firstsendto
)
1242 /* server for wrong domain */
1243 if (type
!= (last_server
->flags
& SERV_TYPE
) ||
1244 (type
== SERV_HAS_DOMAIN
&& !hostname_isequal(domain
, last_server
->domain
)))
1247 if (last_server
->tcpfd
== -1)
1249 if ((last_server
->tcpfd
= socket(last_server
->addr
.sa
.sa_family
, SOCK_STREAM
, 0)) == -1)
1252 if ((!local_bind(last_server
->tcpfd
, &last_server
->source_addr
, last_server
->interface
, 1) ||
1253 connect(last_server
->tcpfd
, &last_server
->addr
.sa
, sa_len(&last_server
->addr
)) == -1))
1255 close(last_server
->tcpfd
);
1256 last_server
->tcpfd
= -1;
1260 #ifdef HAVE_CONNTRACK
1261 /* Copy connection mark of incoming query to outgoing connection. */
1262 if (option_bool(OPT_CONNTRACK
))
1265 struct all_addr local
;
1267 if (local_addr
->sa
.sa_family
== AF_INET6
)
1268 local
.addr
.addr6
= local_addr
->in6
.sin6_addr
;
1271 local
.addr
.addr4
= local_addr
->in
.sin_addr
;
1273 if (get_incoming_mark(&peer_addr
, &local
, 1, &mark
))
1274 setsockopt(last_server
->tcpfd
, SOL_SOCKET
, SO_MARK
, &mark
, sizeof(unsigned int));
1279 *length
= htons(size
);
1281 if (!read_write(last_server
->tcpfd
, packet
, size
+ sizeof(u16
), 0) ||
1282 !read_write(last_server
->tcpfd
, &c1
, 1, 1) ||
1283 !read_write(last_server
->tcpfd
, &c2
, 1, 1))
1285 close(last_server
->tcpfd
);
1286 last_server
->tcpfd
= -1;
1291 if (!read_write(last_server
->tcpfd
, payload
, m
, 1))
1295 strcpy(daemon
->namebuff
, "query");
1296 if (last_server
->addr
.sa
.sa_family
== AF_INET
)
1297 log_query(F_SERVER
| F_IPV4
| F_FORWARD
, daemon
->namebuff
,
1298 (struct all_addr
*)&last_server
->addr
.in
.sin_addr
, NULL
);
1301 log_query(F_SERVER
| F_IPV6
| F_FORWARD
, daemon
->namebuff
,
1302 (struct all_addr
*)&last_server
->addr
.in6
.sin6_addr
, NULL
);
1305 /* There's no point in updating the cache, since this process will exit and
1306 lose the information after a few queries. We make this call for the alias and
1307 bogus-nxdomain side-effects. */
1308 /* If the crc of the question section doesn't match the crc we sent, then
1309 someone might be attempting to insert bogus values into the cache by
1310 sending replies containing questions and bogus answers. */
1311 if (crc
== questions_crc(header
, (unsigned int)m
, daemon
->namebuff
))
1312 m
= process_reply(header
, now
, last_server
, (unsigned int)m
,
1313 option_bool(OPT_NO_REBIND
) && !norebind
, checking_disabled
,
1314 0, check_subnet
, &peer_addr
); /* TODO - cache secure */
1320 /* In case of local answer or no connections made. */
1322 m
= setup_reply(header
, (unsigned int)size
, addrp
, flags
, daemon
->local_ttl
);
1326 check_log_writer(NULL
);
1330 if (m
== 0 || !read_write(confd
, packet
, m
+ sizeof(u16
), 0))
1335 static struct frec
*allocate_frec(time_t now
)
1339 if ((f
= (struct frec
*)whine_malloc(sizeof(struct frec
))))
1341 f
->next
= daemon
->frec_list
;
1350 f
->blocking_query
= NULL
;
1352 daemon
->frec_list
= f
;
1358 static struct randfd
*allocate_rfd(int family
)
1360 static int finger
= 0;
1363 /* limit the number of sockets we have open to avoid starvation of
1364 (eg) TFTP. Once we have a reasonable number, randomness should be OK */
1366 for (i
= 0; i
< RANDOM_SOCKS
; i
++)
1367 if (daemon
->randomsocks
[i
].refcount
== 0)
1369 if ((daemon
->randomsocks
[i
].fd
= random_sock(family
)) == -1)
1372 daemon
->randomsocks
[i
].refcount
= 1;
1373 daemon
->randomsocks
[i
].family
= family
;
1374 return &daemon
->randomsocks
[i
];
1377 /* No free ones or cannot get new socket, grab an existing one */
1378 for (i
= 0; i
< RANDOM_SOCKS
; i
++)
1380 int j
= (i
+finger
) % RANDOM_SOCKS
;
1381 if (daemon
->randomsocks
[j
].refcount
!= 0 &&
1382 daemon
->randomsocks
[j
].family
== family
&&
1383 daemon
->randomsocks
[j
].refcount
!= 0xffff)
1386 daemon
->randomsocks
[j
].refcount
++;
1387 return &daemon
->randomsocks
[j
];
1391 return NULL
; /* doom */
1393 static void free_frec(struct frec
*f
)
1395 if (f
->rfd4
&& --(f
->rfd4
->refcount
) == 0)
1403 if (f
->rfd6
&& --(f
->rfd6
->refcount
) == 0)
1412 blockdata_free(f
->stash
);
1416 /* Anything we're waiting on is pointless now, too */
1417 if (f
->blocking_query
)
1418 free_frec(f
->blocking_query
);
1419 f
->blocking_query
= NULL
;
1424 /* if wait==NULL return a free or older than TIMEOUT record.
1425 else return *wait zero if one available, or *wait is delay to
1426 when the oldest in-use record will expire. Impose an absolute
1427 limit of 4*TIMEOUT before we wipe things (for random sockets).
1428 If force is set, always return a result, even if we have
1429 to allocate above the limit. */
1430 struct frec
*get_new_frec(time_t now
, int *wait
, int force
)
1432 struct frec
*f
, *oldest
, *target
;
1438 for (f
= daemon
->frec_list
, oldest
= NULL
, target
= NULL
, count
= 0; f
; f
= f
->next
, count
++)
1443 if (difftime(now
, f
->time
) >= 4*TIMEOUT
)
1449 if (!oldest
|| difftime(f
->time
, oldest
->time
) <= 0)
1459 /* can't find empty one, use oldest if there is one
1460 and it's older than timeout */
1461 if (oldest
&& ((int)difftime(now
, oldest
->time
)) >= TIMEOUT
)
1463 /* keep stuff for twice timeout if we can by allocating a new
1465 if (difftime(now
, oldest
->time
) < 2*TIMEOUT
&&
1466 count
<= daemon
->ftabsize
&&
1467 (f
= allocate_frec(now
)))
1478 /* none available, calculate time 'till oldest record expires */
1479 if (!force
&& count
> daemon
->ftabsize
)
1481 static time_t last_log
= 0;
1484 *wait
= oldest
->time
+ (time_t)TIMEOUT
- now
;
1486 if ((int)difftime(now
, last_log
) > 5)
1489 my_syslog(LOG_WARNING
, _("Maximum number of concurrent DNS queries reached (max: %d)"), daemon
->ftabsize
);
1495 if (!(f
= allocate_frec(now
)) && wait
)
1496 /* wait one second on malloc failure */
1499 return f
; /* OK if malloc fails and this is NULL */
1502 /* crc is all-ones if not known. */
1503 static struct frec
*lookup_frec(unsigned short id
, unsigned int crc
)
1507 for(f
= daemon
->frec_list
; f
; f
= f
->next
)
1508 if (f
->sentto
&& f
->new_id
== id
&&
1509 (f
->crc
== crc
|| crc
== 0xffffffff))
1515 static struct frec
*lookup_frec_by_sender(unsigned short id
,
1516 union mysockaddr
*addr
,
1521 for(f
= daemon
->frec_list
; f
; f
= f
->next
)
1525 sockaddr_isequal(&f
->source
, addr
))
1531 /* A server record is going away, remove references to it */
1532 void server_gone(struct server
*server
)
1536 for (f
= daemon
->frec_list
; f
; f
= f
->next
)
1537 if (f
->sentto
&& f
->sentto
== server
)
1540 if (daemon
->last_server
== server
)
1541 daemon
->last_server
= NULL
;
1543 if (daemon
->srv_save
== server
)
1544 daemon
->srv_save
= NULL
;
1547 /* return unique random ids. */
1548 static unsigned short get_id(unsigned int crc
)
1550 unsigned short ret
= 0;
1554 while (lookup_frec(ret
, crc
));