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/>.
16 /* Jon Zarate AFAIK wrote the original Tomato specific code, primarily to
17 support extra info in the GUI. Following is a vague clue as to how it
20 device list status is handled by www/devlist.c - this sends a SIGUSR2
21 to dnsmasq which causes the 'tomato_helper' function to execute in
22 addition to the normal dnsmasq SIGUSR2 code (Switch logfile, but since
23 Tomato not using that it doesn't matter) devlist.c waits up to 5 secs
24 for file '/var/tmp/dhcp/leases.!' to disappear before continuing
25 (Must be a better way to do this IPC stuff)
27 tomato_helper(lease.c) does a couple of things:
29 It looks for /var/tmp/dhcp/delete and deletes any known leases by IP
30 address found therein. It deletes /var/tmp/dhcp/delete when done.
31 This implements the 'delete lease' from GUI functionality.
33 It dumps the current dhcp leases into /var/tmp/dhcp/lease.! (tmp file)
34 subtracting the current time from the lease expiry time, thus producing
35 a 'lease remaining' time for the GUI.
36 The temp file is renamed to /var/tmp/dhcp/leases thus signalling devlist.c
37 that it may proceed. Finally when devlist.c is finished
38 /var/tmp/dhcp/leases is removed.
40 rfc2131.c implements a 'Quiet DHCP' option (don't log DHCP stuff) first
41 implemented by 'Teddy Bear'.
43 dnsmasq.c also intercepts SIGHUP so that it may flush the lease file.
44 This is so lease expiry times survive a process restart since dnsmasq
45 reads the lease file at start-up.
47 Finally(?) lease_update_file (lease.c) writes out the remaining lease
48 duration for each dhcp lease rather than lease expiry time (with RTC) or
49 lease length (no RTC) for dnsmasq's internal lease database.
50 asuswrt does a similar thing with lease durations though the code is
51 different. Ideally the code would be merged in such a way that Tomato
52 and asuswrt-merlin can code share without even thinking...another project!
54 dhcp lease file is /var/lib/misc/dnsmasq.leases
56 Above description K Darbyshire-Bryant 02/05/13 Hope it helps someone
61 /* Declare static char *compiler_opts in config.h */
62 #define DNSMASQ_COMPILE_OPTS
66 struct daemon
*daemon
;
68 static volatile pid_t pid
= 0;
69 static volatile int pipewrite
;
71 static int set_dns_listeners(time_t now
, fd_set
*set
, int *maxfdp
);
72 static void check_dns_listeners(fd_set
*set
, time_t now
);
73 static void sig_handler(int sig
);
74 static void async_event(int pipe
, time_t now
);
75 static void fatal_event(struct event_desc
*ev
, char *msg
);
76 static int read_event(int fd
, struct event_desc
*evp
, char **msg
);
78 int main (int argc
, char **argv
)
80 int bind_fallback
= 0;
82 struct sigaction sigact
;
84 int piperead
, pipefd
[2], err_pipe
[2];
85 struct passwd
*ent_pw
= NULL
;
86 #if defined(HAVE_SCRIPT)
90 struct group
*gp
= NULL
;
91 long i
, max_fd
= sysconf(_SC_OPEN_MAX
);
94 #if defined(HAVE_LINUX_NETWORK)
95 cap_user_header_t hdr
= NULL
;
96 cap_user_data_t data
= NULL
;
98 struct dhcp_context
*context
;
99 struct dhcp_relay
*relay
;
102 setlocale(LC_ALL
, "");
103 bindtextdomain("dnsmasq", LOCALEDIR
);
104 textdomain("dnsmasq");
107 sigact
.sa_handler
= sig_handler
;
109 sigemptyset(&sigact
.sa_mask
);
110 sigaction(SIGUSR1
, &sigact
, NULL
);
111 sigaction(SIGUSR2
, &sigact
, NULL
);
112 sigaction(SIGHUP
, &sigact
, NULL
);
113 sigaction(SIGTERM
, &sigact
, NULL
);
114 sigaction(SIGALRM
, &sigact
, NULL
);
115 sigaction(SIGCHLD
, &sigact
, NULL
);
118 sigact
.sa_handler
= SIG_IGN
;
119 sigaction(SIGPIPE
, &sigact
, NULL
);
121 umask(022); /* known umask, create leases and pid files as 0644 */
123 read_opts(argc
, argv
, compile_opts
);
125 if (daemon
->edns_pktsz
< PACKETSZ
)
126 daemon
->edns_pktsz
= PACKETSZ
;
127 daemon
->packet_buff_sz
= daemon
->edns_pktsz
> DNSMASQ_PACKETSZ
?
128 daemon
->edns_pktsz
: DNSMASQ_PACKETSZ
;
129 daemon
->packet
= safe_malloc(daemon
->packet_buff_sz
);
131 daemon
->addrbuff
= safe_malloc(ADDRSTRLEN
);
135 if (!daemon
->lease_file
)
137 if (daemon
->dhcp
|| daemon
->dhcp6
)
138 daemon
->lease_file
= LEASEFILE
;
142 /* Close any file descriptors we inherited apart from std{in|out|err}
144 Ensure that at least stdin, stdout and stderr (fd 0, 1, 2) exist,
145 otherwise file descriptors we create can end up being 0, 1, or 2
146 and then get accidentally closed later when we make 0, 1, and 2
147 open to /dev/null. Normally we'll be started with 0, 1 and 2 open,
148 but it's not guaranteed. By opening /dev/null three times, we
149 ensure that we're not using those fds for real stuff. */
150 for (i
= 0; i
< max_fd
; i
++)
151 if (i
!= STDOUT_FILENO
&& i
!= STDERR_FILENO
&& i
!= STDIN_FILENO
)
154 open("/dev/null", O_RDWR
);
156 #ifndef HAVE_LINUX_NETWORK
157 # if !(defined(IP_RECVDSTADDR) && defined(IP_RECVIF) && defined(IP_SENDSRCADDR))
158 if (!option_bool(OPT_NOWILD
))
161 set_option_bool(OPT_NOWILD
);
165 /* -- bind-dynamic not supported on !Linux, fall back to --bind-interfaces */
166 if (option_bool(OPT_CLEVERBIND
))
169 set_option_bool(OPT_NOWILD
);
170 reset_option_bool(OPT_CLEVERBIND
);
175 if (option_bool(OPT_TFTP
))
176 die(_("TFTP server not available: set HAVE_TFTP in src/config.h"), NULL
, EC_BADCONF
);
179 #ifdef HAVE_CONNTRACK
180 if (option_bool(OPT_CONNTRACK
) && (daemon
->query_port
!= 0 || daemon
->osport
))
181 die (_("Cannot use --conntrack AND --query-port"), NULL
, EC_BADCONF
);
183 if (option_bool(OPT_CONNTRACK
))
184 die(_("Conntrack support not available: set HAVE_CONNTRACK in src/config.h"), NULL
, EC_BADCONF
);
187 #ifdef HAVE_SOLARIS_NETWORK
188 if (daemon
->max_logs
!= 0)
189 die(_("asychronous logging is not available under Solaris"), NULL
, EC_BADCONF
);
193 if (daemon
->max_logs
!= 0)
194 die(_("asychronous logging is not available under Android"), NULL
, EC_BADCONF
);
198 if (daemon
->authserver
)
199 die(_("authoritative DNS not available: set HAVE_AUTH in src/config.h"), NULL
, EC_BADCONF
);
204 now
= dnsmasq_time();
206 /* Create a serial at startup if not configured. */
207 if (daemon
->authinterface
&& daemon
->soa_sn
== 0)
208 #ifdef HAVE_BROKEN_RTC
209 die(_("zone serial must be configured in --auth-soa"), NULL
, EC_BADCONF
);
211 daemon
->soa_sn
= now
;
217 daemon
->doing_ra
= option_bool(OPT_RA
);
219 for (context
= daemon
->dhcp6
; context
; context
= context
->next
)
221 if (context
->flags
& CONTEXT_DHCP
)
222 daemon
->doing_dhcp6
= 1;
223 if (context
->flags
& CONTEXT_RA
)
224 daemon
->doing_ra
= 1;
225 #ifndef HAVE_LINUX_NETWORK
226 if (context
->flags
& CONTEXT_TEMPLATE
)
227 die (_("dhcp-range constructor not available on this platform"), NULL
, EC_BADCONF
);
234 /* Note that order matters here, we must call lease_init before
235 creating any file descriptors which shouldn't be leaked
236 to the lease-script init process. We need to call common_init
237 before lease_init to allocate buffers it uses.*/
238 if (daemon
->dhcp
|| daemon
->doing_dhcp6
|| daemon
->relay4
|| daemon
->relay6
)
241 if (daemon
->dhcp
|| daemon
->doing_dhcp6
)
245 if (daemon
->dhcp
|| daemon
->relay4
)
249 if (daemon
->doing_ra
)
252 if (daemon
->doing_dhcp6
|| daemon
->relay6
)
263 #ifdef HAVE_LINUX_NETWORK
266 if (option_bool(OPT_NOWILD
) && option_bool(OPT_CLEVERBIND
))
267 die(_("cannot set --bind-interfaces and --bind-dynamic"), NULL
, EC_BADCONF
);
270 if (!enumerate_interfaces(1) || !enumerate_interfaces(0))
271 die(_("failed to find list of interfaces: %s"), NULL
, EC_MISC
);
273 if (option_bool(OPT_NOWILD
) || option_bool(OPT_CLEVERBIND
))
275 create_bound_listeners(1);
277 if (!option_bool(OPT_CLEVERBIND
))
278 for (if_tmp
= daemon
->if_names
; if_tmp
; if_tmp
= if_tmp
->next
)
279 if (if_tmp
->name
&& !if_tmp
->used
)
280 die(_("unknown interface %s"), if_tmp
->name
, EC_BADNET
);
282 #if defined(HAVE_LINUX_NETWORK) && defined(HAVE_DHCP)
283 /* after enumerate_interfaces() */
287 bindtodevice(daemon
->dhcpfd
);
288 if (daemon
->enable_pxe
)
289 bindtodevice(daemon
->pxefd
);
293 #if defined(HAVE_LINUX_NETWORK) && defined(HAVE_DHCP6)
294 if (daemon
->doing_dhcp6
&& !daemon
->relay6
)
295 bindtodevice(daemon
->dhcp6fd
);
299 create_wildcard_listeners();
302 /* after enumerate_interfaces() */
303 if (daemon
->doing_dhcp6
|| daemon
->relay6
|| daemon
->doing_ra
)
307 if (daemon
->port
!= 0)
310 if (option_bool(OPT_DBUS
))
315 daemon
->watches
= NULL
;
316 if ((err
= dbus_init()))
317 die(_("DBus error: %s"), err
, EC_MISC
);
320 die(_("DBus not available: set HAVE_DBUS in src/config.h"), NULL
, EC_BADCONF
);
323 if (daemon
->port
!= 0)
326 #if defined(HAVE_SCRIPT)
327 /* Note getpwnam returns static storage */
328 if ((daemon
->dhcp
|| daemon
->dhcp6
) &&
329 daemon
->scriptuser
&&
330 (daemon
->lease_change_command
|| daemon
->luascript
))
332 if ((ent_pw
= getpwnam(daemon
->scriptuser
)))
334 script_uid
= ent_pw
->pw_uid
;
335 script_gid
= ent_pw
->pw_gid
;
338 baduser
= daemon
->scriptuser
;
342 if (daemon
->username
&& !(ent_pw
= getpwnam(daemon
->username
)))
343 baduser
= daemon
->username
;
344 else if (daemon
->groupname
&& !(gp
= getgrnam(daemon
->groupname
)))
345 baduser
= daemon
->groupname
;
348 die(_("unknown user or group: %s"), baduser
, EC_BADCONF
);
350 /* implement group defaults, "dip" if available, or group associated with uid */
351 if (!daemon
->group_set
&& !gp
)
353 if (!(gp
= getgrnam(CHGRP
)) && ent_pw
)
354 gp
= getgrgid(ent_pw
->pw_gid
);
356 /* for error message */
358 daemon
->groupname
= gp
->gr_name
;
361 #if defined(HAVE_LINUX_NETWORK)
362 /* determine capability API version here, while we can still
364 if (ent_pw
&& ent_pw
->pw_uid
!= 0)
366 int capsize
= 1; /* for header version 1 */
367 hdr
= safe_malloc(sizeof(*hdr
));
369 /* find version supported by kernel */
370 memset(hdr
, 0, sizeof(*hdr
));
373 if (hdr
->version
!= LINUX_CAPABILITY_VERSION_1
)
375 /* if unknown version, use largest supported version (3) */
376 if (hdr
->version
!= LINUX_CAPABILITY_VERSION_2
)
377 hdr
->version
= LINUX_CAPABILITY_VERSION_3
;
381 data
= safe_malloc(sizeof(*data
) * capsize
);
382 memset(data
, 0, sizeof(*data
) * capsize
);
386 /* Use a pipe to carry signals and other events back to the event loop
387 in a race-free manner and another to carry errors to daemon-invoking process */
388 safe_pipe(pipefd
, 1);
390 piperead
= pipefd
[0];
391 pipewrite
= pipefd
[1];
392 /* prime the pipe to load stuff first time. */
393 send_event(pipewrite
, EVENT_RELOAD
, 0, NULL
);
397 if (!option_bool(OPT_DEBUG
))
399 /* The following code "daemonizes" the process.
400 See Stevens section 12.4 */
403 die(_("cannot chdir to filesystem root: %s"), NULL
, EC_MISC
);
406 if (!option_bool(OPT_NO_FORK
))
410 /* pipe to carry errors back to original process.
411 When startup is complete we close this and the process terminates. */
412 safe_pipe(err_pipe
, 0);
414 if ((pid
= fork()) == -1)
415 /* fd == -1 since we've not forked, never returns. */
416 send_event(-1, EVENT_FORK_ERR
, errno
, NULL
);
420 struct event_desc ev
;
423 /* close our copy of write-end */
426 /* check for errors after the fork */
427 if (read_event(err_pipe
[0], &ev
, &msg
))
428 fatal_event(&ev
, msg
);
435 /* NO calls to die() from here on. */
439 if ((pid
= fork()) == -1)
440 send_event(err_pipe
[1], EVENT_FORK_ERR
, errno
, NULL
);
447 /* write pidfile _after_ forking ! */
452 sprintf(daemon
->namebuff
, "%d\n", (int) getpid());
454 /* Explanation: Some installations of dnsmasq (eg Debian/Ubuntu) locate the pid-file
455 in a directory which is writable by the non-privileged user that dnsmasq runs as. This
456 allows the daemon to delete the file as part of its shutdown. This is a security hole to the
457 extent that an attacker running as the unprivileged user could replace the pidfile with a
458 symlink, and have the target of that symlink overwritten as root next time dnsmasq starts.
460 The folowing code first deletes any existing file, and then opens it with the O_EXCL flag,
461 ensuring that the open() fails should there be any existing file (because the unlink() failed,
462 or an attacker exploited the race between unlink() and open()). This ensures that no symlink
465 Any compromise of the non-privileged user still theoretically allows the pid-file to be
466 replaced whilst dnsmasq is running. The worst that could allow is that the usual
467 "shutdown dnsmasq" shell command could be tricked into stopping any other process.
469 Note that if dnsmasq is started as non-root (eg for testing) it silently ignores
470 failure to write the pid-file.
473 unlink(daemon
->runfile
);
475 if ((fd
= open(daemon
->runfile
, O_WRONLY
|O_CREAT
|O_TRUNC
|O_EXCL
, S_IWUSR
|S_IRUSR
|S_IRGRP
|S_IROTH
)) == -1)
477 /* only complain if started as root */
483 if (!read_write(fd
, (unsigned char *)daemon
->namebuff
, strlen(daemon
->namebuff
), 0))
486 while (!err
&& close(fd
) == -1)
493 send_event(err_pipe
[1], EVENT_PIDFILE
, errno
, daemon
->runfile
);
499 log_err
= log_start(ent_pw
, err_pipe
[1]);
501 if (!option_bool(OPT_DEBUG
))
503 /* open stdout etc to /dev/null */
504 int nullfd
= open("/dev/null", O_RDWR
);
505 dup2(nullfd
, STDOUT_FILENO
);
506 dup2(nullfd
, STDERR_FILENO
);
507 dup2(nullfd
, STDIN_FILENO
);
511 /* if we are to run scripts, we need to fork a helper before dropping root. */
512 daemon
->helperfd
= -1;
514 if ((daemon
->dhcp
|| daemon
->dhcp6
) && (daemon
->lease_change_command
|| daemon
->luascript
))
515 daemon
->helperfd
= create_helper(pipewrite
, err_pipe
[1], script_uid
, script_gid
, max_fd
);
518 if (!option_bool(OPT_DEBUG
) && getuid() == 0)
520 int bad_capabilities
= 0;
523 /* remove all supplimentary groups */
525 (setgroups(0, &dummy
) == -1 ||
526 setgid(gp
->gr_gid
) == -1))
528 send_event(err_pipe
[1], EVENT_GROUP_ERR
, errno
, daemon
->groupname
);
532 if (ent_pw
&& ent_pw
->pw_uid
!= 0)
534 #if defined(HAVE_LINUX_NETWORK)
535 /* On linux, we keep CAP_NETADMIN (for ARP-injection) and
536 CAP_NET_RAW (for icmp) if we're doing dhcp. If we have yet to bind
537 ports because of DAD, or we're doing it dynamically,
538 we need CAP_NET_BIND_SERVICE too. */
539 if (is_dad_listeners() || option_bool(OPT_CLEVERBIND
))
540 data
->effective
= data
->permitted
= data
->inheritable
=
541 (1 << CAP_NET_ADMIN
) | (1 << CAP_NET_RAW
) |
542 (1 << CAP_SETUID
) | (1 << CAP_NET_BIND_SERVICE
);
544 data
->effective
= data
->permitted
= data
->inheritable
=
545 (1 << CAP_NET_ADMIN
) | (1 << CAP_NET_RAW
) | (1 << CAP_SETUID
);
547 /* Tell kernel to not clear capabilities when dropping root */
548 if (capset(hdr
, data
) == -1 || prctl(PR_SET_KEEPCAPS
, 1, 0, 0, 0) == -1)
549 bad_capabilities
= errno
;
551 #elif defined(HAVE_SOLARIS_NETWORK)
552 /* http://developers.sun.com/solaris/articles/program_privileges.html */
553 priv_set_t
*priv_set
;
555 if (!(priv_set
= priv_str_to_set("basic", ",", NULL
)) ||
556 priv_addset(priv_set
, PRIV_NET_ICMPACCESS
) == -1 ||
557 priv_addset(priv_set
, PRIV_SYS_NET_CONFIG
) == -1)
558 bad_capabilities
= errno
;
560 if (priv_set
&& bad_capabilities
== 0)
562 priv_inverse(priv_set
);
564 if (setppriv(PRIV_OFF
, PRIV_LIMIT
, priv_set
) == -1)
565 bad_capabilities
= errno
;
569 priv_freeset(priv_set
);
573 if (bad_capabilities
!= 0)
575 send_event(err_pipe
[1], EVENT_CAP_ERR
, bad_capabilities
, NULL
);
579 /* finally drop root */
580 if (setuid(ent_pw
->pw_uid
) == -1)
582 send_event(err_pipe
[1], EVENT_USER_ERR
, errno
, daemon
->username
);
586 #ifdef HAVE_LINUX_NETWORK
587 if (is_dad_listeners() || option_bool(OPT_CLEVERBIND
))
588 data
->effective
= data
->permitted
=
589 (1 << CAP_NET_ADMIN
) | (1 << CAP_NET_RAW
) | (1 << CAP_NET_BIND_SERVICE
);
591 data
->effective
= data
->permitted
=
592 (1 << CAP_NET_ADMIN
) | (1 << CAP_NET_RAW
);
593 data
->inheritable
= 0;
595 /* lose the setuid and setgid capbilities */
596 if (capset(hdr
, data
) == -1)
598 send_event(err_pipe
[1], EVENT_CAP_ERR
, errno
, NULL
);
606 #ifdef HAVE_LINUX_NETWORK
607 if (option_bool(OPT_DEBUG
))
608 prctl(PR_SET_DUMPABLE
, 1, 0, 0, 0);
612 if (option_bool(OPT_TFTP
))
615 struct tftp_prefix
*p
;
617 if (daemon
->tftp_prefix
)
619 if (!((dir
= opendir(daemon
->tftp_prefix
))))
621 send_event(err_pipe
[1], EVENT_TFTP_ERR
, errno
, daemon
->tftp_prefix
);
627 for (p
= daemon
->if_prefix
; p
; p
= p
->next
)
629 if (!((dir
= opendir(p
->prefix
))))
631 send_event(err_pipe
[1], EVENT_TFTP_ERR
, errno
, p
->prefix
);
639 if (daemon
->port
== 0)
640 my_syslog(LOG_INFO
, _("started, version %s DNS disabled"), VERSION
);
641 else if (daemon
->cachesize
!= 0)
642 my_syslog(LOG_INFO
, _("started, version %s cachesize %d"), VERSION
, daemon
->cachesize
);
644 my_syslog(LOG_INFO
, _("started, version %s cache disabled"), VERSION
);
646 my_syslog(LOG_INFO
, _("compile time options: %s"), compile_opts
);
649 if (option_bool(OPT_DBUS
))
652 my_syslog(LOG_INFO
, _("DBus support enabled: connected to system bus"));
654 my_syslog(LOG_INFO
, _("DBus support enabled: bus connection pending"));
659 my_syslog(LOG_WARNING
, _("warning: failed to change owner of %s: %s"),
660 daemon
->log_file
, strerror(log_err
));
663 my_syslog(LOG_WARNING
, _("setting --bind-interfaces option because of OS limitations"));
665 if (!option_bool(OPT_NOWILD
))
666 for (if_tmp
= daemon
->if_names
; if_tmp
; if_tmp
= if_tmp
->next
)
667 if (if_tmp
->name
&& !if_tmp
->used
)
668 my_syslog(LOG_WARNING
, _("warning: interface %s does not currently exist"), if_tmp
->name
);
670 if (daemon
->port
!= 0 && option_bool(OPT_NO_RESOLV
))
672 if (daemon
->resolv_files
&& !daemon
->resolv_files
->is_default
)
673 my_syslog(LOG_WARNING
, _("warning: ignoring resolv-file flag because no-resolv is set"));
674 daemon
->resolv_files
= NULL
;
675 if (!daemon
->servers
)
676 my_syslog(LOG_WARNING
, _("warning: no upstream servers configured"));
679 if (daemon
->max_logs
!= 0)
680 my_syslog(LOG_INFO
, _("asynchronous logging enabled, queue limit is %d messages"), daemon
->max_logs
);
684 for (context
= daemon
->dhcp
; context
; context
= context
->next
)
685 log_context(AF_INET
, context
);
687 for (relay
= daemon
->relay4
; relay
; relay
= relay
->next
)
688 log_relay(AF_INET
, relay
);
691 for (context
= daemon
->dhcp6
; context
; context
= context
->next
)
692 log_context(AF_INET6
, context
);
694 for (relay
= daemon
->relay6
; relay
; relay
= relay
->next
)
695 log_relay(AF_INET6
, relay
);
697 if (daemon
->doing_dhcp6
|| daemon
->doing_ra
)
698 dhcp_construct_contexts(now
);
700 if (option_bool(OPT_RA
))
701 my_syslog(MS_DHCP
| LOG_INFO
, _("IPv6 router advertisement enabled"));
704 /* after dhcp_contruct_contexts */
705 if (daemon
->dhcp
|| daemon
->doing_dhcp6
)
706 lease_find_interfaces(now
);
710 if (option_bool(OPT_TFTP
))
713 if (FD_SETSIZE
< (unsigned)max_fd
)
717 my_syslog(MS_TFTP
| LOG_INFO
, "TFTP %s%s %s",
718 daemon
->tftp_prefix
? _("root is ") : _("enabled"),
719 daemon
->tftp_prefix
? daemon
->tftp_prefix
: "",
720 option_bool(OPT_TFTP_SECURE
) ? _("secure mode") : "");
722 /* This is a guess, it assumes that for small limits,
723 disjoint files might be served, but for large limits,
724 a single file will be sent to may clients (the file only needs
727 max_fd
-= 30; /* use other than TFTP */
731 else if (max_fd
< 100)
734 max_fd
= max_fd
- 20;
736 /* if we have to use a limited range of ports,
737 that will limit the number of transfers */
738 if (daemon
->start_tftp_port
!= 0 &&
739 daemon
->end_tftp_port
- daemon
->start_tftp_port
+ 1 < max_fd
)
740 max_fd
= daemon
->end_tftp_port
- daemon
->start_tftp_port
+ 1;
742 if (daemon
->tftp_max
> max_fd
)
744 daemon
->tftp_max
= max_fd
;
745 my_syslog(MS_TFTP
| LOG_WARNING
,
746 _("restricting maximum simultaneous TFTP transfers to %d"),
752 /* finished start-up - release original process */
753 if (err_pipe
[1] != -1)
756 if (daemon
->port
!= 0)
764 struct timeval t
, *tp
= NULL
;
765 fd_set rset
, wset
, eset
;
771 /* if we are out of resources, find how long we have to wait
772 for some to come free, we'll loop around then and restart
773 listening for queries */
774 if ((t
.tv_sec
= set_dns_listeners(now
, &rset
, &maxfd
)) != 0)
780 /* Whilst polling for the dbus, or doing a tftp transfer, wake every quarter second */
781 if (daemon
->tftp_trans
||
782 (option_bool(OPT_DBUS
) && !daemon
->dbus
))
788 /* Wake every second whilst waiting for DAD to complete */
789 else if (is_dad_listeners())
797 set_dbus_listeners(&maxfd
, &rset
, &wset
, &eset
);
801 if (daemon
->dhcp
|| daemon
->relay4
)
803 FD_SET(daemon
->dhcpfd
, &rset
);
804 bump_maxfd(daemon
->dhcpfd
, &maxfd
);
805 if (daemon
->pxefd
!= -1)
807 FD_SET(daemon
->pxefd
, &rset
);
808 bump_maxfd(daemon
->pxefd
, &maxfd
);
814 if (daemon
->doing_dhcp6
|| daemon
->relay6
)
816 FD_SET(daemon
->dhcp6fd
, &rset
);
817 bump_maxfd(daemon
->dhcp6fd
, &maxfd
);
820 if (daemon
->doing_ra
)
822 FD_SET(daemon
->icmp6fd
, &rset
);
823 bump_maxfd(daemon
->icmp6fd
, &maxfd
);
827 #ifdef HAVE_LINUX_NETWORK
828 FD_SET(daemon
->netlinkfd
, &rset
);
829 bump_maxfd(daemon
->netlinkfd
, &maxfd
);
832 FD_SET(piperead
, &rset
);
833 bump_maxfd(piperead
, &maxfd
);
837 while (helper_buf_empty() && do_script_run(now
));
840 while (helper_buf_empty() && do_tftp_script_run());
843 if (!helper_buf_empty())
845 FD_SET(daemon
->helperfd
, &wset
);
846 bump_maxfd(daemon
->helperfd
, &maxfd
);
849 /* need this for other side-effects */
850 while (do_script_run(now
));
853 while (do_tftp_script_run());
859 /* must do this just before select(), when we know no
860 more calls to my_syslog() can occur */
861 set_log_writer(&wset
, &maxfd
);
863 if (select(maxfd
+1, &rset
, &wset
, &eset
, tp
) < 0)
865 /* otherwise undefined after error */
866 FD_ZERO(&rset
); FD_ZERO(&wset
); FD_ZERO(&eset
);
869 now
= dnsmasq_time();
871 check_log_writer(&wset
);
874 enumerate_interfaces(1);
876 /* Check the interfaces to see if any have exited DAD state
877 and if so, bind the address. */
878 if (is_dad_listeners())
880 enumerate_interfaces(0);
881 /* NB, is_dad_listeners() == 1 --> we're binding interfaces */
882 create_bound_listeners(0);
885 #ifdef HAVE_LINUX_NETWORK
886 if (FD_ISSET(daemon
->netlinkfd
, &rset
))
887 netlink_multicast(now
);
890 /* Check for changes to resolv files once per second max. */
891 /* Don't go silent for long periods if the clock goes backwards. */
892 if (daemon
->last_resolv
== 0 ||
893 difftime(now
, daemon
->last_resolv
) > 1.0 ||
894 difftime(now
, daemon
->last_resolv
) < -1.0)
896 /* poll_resolv doesn't need to reload first time through, since
897 that's queued anyway. */
899 poll_resolv(0, daemon
->last_resolv
!= 0, now
);
900 daemon
->last_resolv
= now
;
903 if (FD_ISSET(piperead
, &rset
))
904 async_event(piperead
, now
);
907 /* if we didn't create a DBus connection, retry now. */
908 if (option_bool(OPT_DBUS
) && !daemon
->dbus
)
911 if ((err
= dbus_init()))
912 my_syslog(LOG_WARNING
, _("DBus error: %s"), err
);
914 my_syslog(LOG_INFO
, _("connected to system DBus"));
916 check_dbus_listeners(&rset
, &wset
, &eset
);
919 check_dns_listeners(&rset
, now
);
922 check_tftp_listeners(&rset
, now
);
926 if (daemon
->dhcp
|| daemon
->relay4
)
928 if (FD_ISSET(daemon
->dhcpfd
, &rset
))
930 if (daemon
->pxefd
!= -1 && FD_ISSET(daemon
->pxefd
, &rset
))
935 if ((daemon
->doing_dhcp6
|| daemon
->relay6
) && FD_ISSET(daemon
->dhcp6fd
, &rset
))
938 if (daemon
->doing_ra
&& FD_ISSET(daemon
->icmp6fd
, &rset
))
943 if (daemon
->helperfd
!= -1 && FD_ISSET(daemon
->helperfd
, &wset
))
951 static void sig_handler(int sig
)
955 /* ignore anything other than TERM during startup
956 and in helper proc. (helper ignore TERM too) */
960 else if (pid
!= getpid())
962 /* alarm is used to kill TCP children after a fixed time. */
969 int event
, errsave
= errno
;
972 event
= EVENT_RELOAD
;
973 else if (sig
== SIGCHLD
)
975 else if (sig
== SIGALRM
)
977 else if (sig
== SIGTERM
)
979 else if (sig
== SIGUSR1
)
981 else if (sig
== SIGUSR2
)
982 event
= EVENT_REOPEN
;
986 send_event(pipewrite
, event
, 0, NULL
);
991 /* now == 0 -> queue immediate callback */
992 void send_alarm(time_t event
, time_t now
)
994 if (now
== 0 || event
!= 0)
996 /* alarm(0) or alarm(-ve) doesn't do what we want.... */
997 if ((now
== 0 || difftime(event
, now
) <= 0.0))
998 send_event(pipewrite
, EVENT_ALARM
, 0, NULL
);
1000 alarm((unsigned)difftime(event
, now
));
1004 void send_event(int fd
, int event
, int data
, char *msg
)
1006 struct event_desc ev
;
1007 struct iovec iov
[2];
1011 ev
.msg_sz
= msg
? strlen(msg
) : 0;
1013 iov
[0].iov_base
= &ev
;
1014 iov
[0].iov_len
= sizeof(ev
);
1015 iov
[1].iov_base
= msg
;
1016 iov
[1].iov_len
= ev
.msg_sz
;
1018 /* error pipe, debug mode. */
1020 fatal_event(&ev
, msg
);
1022 /* pipe is non-blocking and struct event_desc is smaller than
1023 PIPE_BUF, so this either fails or writes everything */
1024 while (writev(fd
, iov
, msg
? 2 : 1) == -1 && errno
== EINTR
);
1027 /* NOTE: the memory used to return msg is leaked: use msgs in events only
1028 to describe fatal errors. */
1029 static int read_event(int fd
, struct event_desc
*evp
, char **msg
)
1033 if (!read_write(fd
, (unsigned char *)evp
, sizeof(struct event_desc
), 1))
1038 if (evp
->msg_sz
!= 0 &&
1039 (buf
= malloc(evp
->msg_sz
+ 1)) &&
1040 read_write(fd
, (unsigned char *)buf
, evp
->msg_sz
, 1))
1042 buf
[evp
->msg_sz
] = 0;
1049 static void fatal_event(struct event_desc
*ev
, char *msg
)
1058 case EVENT_FORK_ERR
:
1059 die(_("cannot fork into background: %s"), NULL
, EC_MISC
);
1061 case EVENT_PIPE_ERR
:
1062 die(_("failed to create helper: %s"), NULL
, EC_MISC
);
1065 die(_("setting capabilities failed: %s"), NULL
, EC_MISC
);
1067 case EVENT_USER_ERR
:
1068 die(_("failed to change user-id to %s: %s"), msg
, EC_MISC
);
1070 case EVENT_GROUP_ERR
:
1071 die(_("failed to change group-id to %s: %s"), msg
, EC_MISC
);
1074 die(_("failed to open pidfile %s: %s"), msg
, EC_FILE
);
1077 die(_("cannot open log %s: %s"), msg
, EC_FILE
);
1080 die(_("failed to load Lua script: %s"), msg
, EC_MISC
);
1082 case EVENT_TFTP_ERR
:
1083 die(_("TFTP directory %s inaccessible: %s"), msg
, EC_FILE
);
1087 static void async_event(int pipe
, time_t now
)
1090 struct event_desc ev
;
1094 /* NOTE: the memory used to return msg is leaked: use msgs in events only
1095 to describe fatal errors. */
1097 if (read_event(pipe
, &ev
, &msg
))
1101 clear_cache_and_reload(now
);
1102 if (daemon
->port
!= 0 && daemon
->resolv_files
&& option_bool(OPT_NO_POLL
))
1104 reload_servers(daemon
->resolv_files
->name
);
1113 if (daemon
->port
!= 0)
1119 if (daemon
->dhcp
|| daemon
->doing_dhcp6
)
1121 lease_prune(NULL
, now
);
1122 lease_update_file(now
);
1125 else if (daemon
->doing_ra
)
1126 /* Not doing DHCP, so no lease system, manage alarms for ra only */
1127 send_alarm(periodic_ra(now
), now
);
1133 /* See Stevens 5.10 */
1134 while ((p
= waitpid(-1, NULL
, WNOHANG
)) != 0)
1141 for (i
= 0 ; i
< MAX_PROCS
; i
++)
1142 if (daemon
->tcp_pids
[i
] == p
)
1143 daemon
->tcp_pids
[i
] = 0;
1147 my_syslog(LOG_WARNING
, _("script process killed by signal %d"), ev
.data
);
1151 my_syslog(LOG_WARNING
, _("script process exited with status %d"), ev
.data
);
1154 case EVENT_EXEC_ERR
:
1155 my_syslog(LOG_ERR
, _("failed to execute %s: %s"),
1156 daemon
->lease_change_command
, strerror(ev
.data
));
1159 /* necessary for fatal errors in helper */
1160 case EVENT_USER_ERR
:
1163 fatal_event(&ev
, msg
);
1167 /* Note: this may leave TCP-handling processes with the old file still open.
1168 Since any such process will die in CHILD_LIFETIME or probably much sooner,
1169 we leave them logging to the old file. */
1170 if (daemon
->log_file
!= NULL
)
1171 log_reopen(daemon
->log_file
);
1174 tomato_helper(now
); //possibly delete & write out leases for tomato
1176 /* following is Asus tweak. Interestingly Asus read the dnsmasq leases db
1177 directly. They signal dnsmasq to update via SIGUSR2 and wait 1 second
1178 assuming the file will be complete by the time they come to parse it.
1179 Race conditions anyone? What if dnsmasq happens to be updating the
1181 #if defined(HAVE_DHCP) && defined(HAVE_LEASEFILE_EXPIRE) && !defined(HAVE_TOMATO)
1182 if (daemon
->dhcp
|| daemon
->dhcp6
)
1183 flush_lease_file(now
);
1188 /* Knock all our children on the head. */
1189 for (i
= 0; i
< MAX_PROCS
; i
++)
1190 if (daemon
->tcp_pids
[i
] != 0)
1191 kill(daemon
->tcp_pids
[i
], SIGALRM
);
1193 #if defined(HAVE_SCRIPT)
1194 /* handle pending lease transitions */
1195 if (daemon
->helperfd
!= -1)
1197 /* block in writes until all done */
1198 if ((i
= fcntl(daemon
->helperfd
, F_GETFL
)) != -1)
1199 fcntl(daemon
->helperfd
, F_SETFL
, i
& ~O_NONBLOCK
);
1202 } while (!helper_buf_empty() || do_script_run(now
));
1203 close(daemon
->helperfd
);
1207 //Originally TOMATO tweak
1208 #if defined(HAVE_DHCP) && defined(HAVE_LEASEFILE_EXPIRE)
1209 if (daemon
->dhcp
|| daemon
->dhcp6
)
1210 flush_lease_file(now
);
1213 if (daemon
->lease_stream
)
1214 fclose(daemon
->lease_stream
);
1216 if (daemon
->runfile
)
1217 unlink(daemon
->runfile
);
1219 my_syslog(LOG_INFO
, _("exiting on receipt of SIGTERM"));
1225 void poll_resolv(int force
, int do_reload
, time_t now
)
1227 struct resolvc
*res
, *latest
;
1228 struct stat statbuf
;
1229 time_t last_change
= 0;
1230 /* There may be more than one possible file.
1231 Go through and find the one which changed _last_.
1232 Warn of any which can't be read. */
1234 if (daemon
->port
== 0 || option_bool(OPT_NO_POLL
))
1237 for (latest
= NULL
, res
= daemon
->resolv_files
; res
; res
= res
->next
)
1238 if (stat(res
->name
, &statbuf
) == -1)
1247 my_syslog(LOG_WARNING
, _("failed to access %s: %s"), res
->name
, strerror(errno
));
1250 if (res
->mtime
!= 0)
1252 /* existing file evaporated, force selection of the latest
1253 file even if its mtime hasn't changed since we last looked */
1254 poll_resolv(1, do_reload
, now
);
1261 if (force
|| (statbuf
.st_mtime
!= res
->mtime
))
1263 res
->mtime
= statbuf
.st_mtime
;
1264 if (difftime(statbuf
.st_mtime
, last_change
) > 0.0)
1266 last_change
= statbuf
.st_mtime
;
1274 static int warned
= 0;
1275 if (reload_servers(latest
->name
))
1277 my_syslog(LOG_INFO
, _("reading %s"), latest
->name
);
1280 if (option_bool(OPT_RELOAD
) && do_reload
)
1281 clear_cache_and_reload(now
);
1288 my_syslog(LOG_WARNING
, _("no servers found in %s, will retry"), latest
->name
);
1295 void clear_cache_and_reload(time_t now
)
1297 if (daemon
->port
!= 0)
1301 if (daemon
->dhcp
|| daemon
->doing_dhcp6
)
1303 if (option_bool(OPT_ETHERS
))
1306 dhcp_update_configs(daemon
->dhcp_conf
);
1307 lease_update_from_configs();
1308 lease_update_file(now
);
1309 lease_update_dns(1);
1312 else if (daemon
->doing_ra
)
1313 /* Not doing DHCP, so no lease system, manage
1314 alarms for ra only */
1315 send_alarm(periodic_ra(now
), now
);
1320 static int set_dns_listeners(time_t now
, fd_set
*set
, int *maxfdp
)
1322 struct serverfd
*serverfdp
;
1323 struct listener
*listener
;
1328 struct tftp_transfer
*transfer
;
1329 for (transfer
= daemon
->tftp_trans
; transfer
; transfer
= transfer
->next
)
1332 FD_SET(transfer
->sockfd
, set
);
1333 bump_maxfd(transfer
->sockfd
, maxfdp
);
1337 /* will we be able to get memory? */
1338 if (daemon
->port
!= 0)
1339 get_new_frec(now
, &wait
);
1341 for (serverfdp
= daemon
->sfds
; serverfdp
; serverfdp
= serverfdp
->next
)
1343 FD_SET(serverfdp
->fd
, set
);
1344 bump_maxfd(serverfdp
->fd
, maxfdp
);
1347 if (daemon
->port
!= 0 && !daemon
->osport
)
1348 for (i
= 0; i
< RANDOM_SOCKS
; i
++)
1349 if (daemon
->randomsocks
[i
].refcount
!= 0)
1351 FD_SET(daemon
->randomsocks
[i
].fd
, set
);
1352 bump_maxfd(daemon
->randomsocks
[i
].fd
, maxfdp
);
1355 for (listener
= daemon
->listeners
; listener
; listener
= listener
->next
)
1357 /* only listen for queries if we have resources */
1358 if (listener
->fd
!= -1 && wait
== 0)
1360 FD_SET(listener
->fd
, set
);
1361 bump_maxfd(listener
->fd
, maxfdp
);
1364 /* death of a child goes through the select loop, so
1365 we don't need to explicitly arrange to wake up here */
1366 if (listener
->tcpfd
!= -1)
1367 for (i
= 0; i
< MAX_PROCS
; i
++)
1368 if (daemon
->tcp_pids
[i
] == 0)
1370 FD_SET(listener
->tcpfd
, set
);
1371 bump_maxfd(listener
->tcpfd
, maxfdp
);
1376 if (tftp
<= daemon
->tftp_max
&& listener
->tftpfd
!= -1)
1378 FD_SET(listener
->tftpfd
, set
);
1379 bump_maxfd(listener
->tftpfd
, maxfdp
);
1388 static void check_dns_listeners(fd_set
*set
, time_t now
)
1390 struct serverfd
*serverfdp
;
1391 struct listener
*listener
;
1394 for (serverfdp
= daemon
->sfds
; serverfdp
; serverfdp
= serverfdp
->next
)
1395 if (FD_ISSET(serverfdp
->fd
, set
))
1396 reply_query(serverfdp
->fd
, serverfdp
->source_addr
.sa
.sa_family
, now
);
1398 if (daemon
->port
!= 0 && !daemon
->osport
)
1399 for (i
= 0; i
< RANDOM_SOCKS
; i
++)
1400 if (daemon
->randomsocks
[i
].refcount
!= 0 &&
1401 FD_ISSET(daemon
->randomsocks
[i
].fd
, set
))
1402 reply_query(daemon
->randomsocks
[i
].fd
, daemon
->randomsocks
[i
].family
, now
);
1404 for (listener
= daemon
->listeners
; listener
; listener
= listener
->next
)
1406 if (listener
->fd
!= -1 && FD_ISSET(listener
->fd
, set
))
1407 receive_query(listener
, now
);
1410 if (listener
->tftpfd
!= -1 && FD_ISSET(listener
->tftpfd
, set
))
1411 tftp_request(listener
, now
);
1414 if (listener
->tcpfd
!= -1 && FD_ISSET(listener
->tcpfd
, set
))
1416 int confd
, client_ok
= 1;
1417 struct irec
*iface
= NULL
;
1419 union mysockaddr tcp_addr
;
1420 socklen_t tcp_len
= sizeof(union mysockaddr
);
1422 while ((confd
= accept(listener
->tcpfd
, NULL
, NULL
)) == -1 && errno
== EINTR
);
1427 if (getsockname(confd
, (struct sockaddr
*)&tcp_addr
, &tcp_len
) == -1)
1433 /* Make sure that the interface list is up-to-date.
1435 We do this here as we may need the results below, and
1436 the DNS code needs them for --interface-name stuff.
1438 Multiple calls to enumerate_interfaces() per select loop are
1439 inhibited, so calls to it in the child process (which doesn't select())
1440 have no effect. This avoids two processes reading from the same
1441 netlink fd and screwing the pooch entirely.
1444 enumerate_interfaces(0);
1446 if (option_bool(OPT_NOWILD
))
1447 iface
= listener
->iface
; /* May be NULL */
1451 char intr_name
[IF_NAMESIZE
];
1453 /* if we can find the arrival interface, check it's one that's allowed */
1454 if ((if_index
= tcp_interface(confd
, tcp_addr
.sa
.sa_family
)) != 0 &&
1455 indextoname(listener
->tcpfd
, if_index
, intr_name
))
1457 struct all_addr addr
;
1458 addr
.addr
.addr4
= tcp_addr
.in
.sin_addr
;
1460 if (tcp_addr
.sa
.sa_family
== AF_INET6
)
1461 addr
.addr
.addr6
= tcp_addr
.in6
.sin6_addr
;
1464 for (iface
= daemon
->interfaces
; iface
; iface
= iface
->next
)
1465 if (iface
->index
== if_index
)
1468 if (!iface
&& !loopback_exception(listener
->tcpfd
, tcp_addr
.sa
.sa_family
, &addr
, intr_name
))
1472 if (option_bool(OPT_CLEVERBIND
))
1473 iface
= listener
->iface
; /* May be NULL */
1476 /* Check for allowed interfaces when binding the wildcard address:
1477 we do this by looking for an interface with the same address as
1478 the local address of the TCP connection, then looking to see if that's
1479 an allowed interface. As a side effect, we get the netmask of the
1480 interface too, for localisation. */
1482 for (iface
= daemon
->interfaces
; iface
; iface
= iface
->next
)
1483 if (sockaddr_isequal(&iface
->addr
, &tcp_addr
))
1493 shutdown(confd
, SHUT_RDWR
);
1497 else if (!option_bool(OPT_DEBUG
) && (p
= fork()) != 0)
1502 for (i
= 0; i
< MAX_PROCS
; i
++)
1503 if (daemon
->tcp_pids
[i
] == 0)
1505 daemon
->tcp_pids
[i
] = p
;
1514 unsigned char *buff
;
1517 struct in_addr netmask
;
1522 netmask
= iface
->netmask
;
1523 auth_dns
= iface
->dns_auth
;
1532 /* Arrange for SIGALARM after CHILD_LIFETIME seconds to
1533 terminate the process. */
1534 if (!option_bool(OPT_DEBUG
))
1535 alarm(CHILD_LIFETIME
);
1538 /* start with no upstream connections. */
1539 for (s
= daemon
->servers
; s
; s
= s
->next
)
1542 /* The connected socket inherits non-blocking
1543 attribute from the listening socket.
1545 if ((flags
= fcntl(confd
, F_GETFL
, 0)) != -1)
1546 fcntl(confd
, F_SETFL
, flags
& ~O_NONBLOCK
);
1548 buff
= tcp_request(confd
, now
, &tcp_addr
, netmask
, auth_dns
);
1550 shutdown(confd
, SHUT_RDWR
);
1556 for (s
= daemon
->servers
; s
; s
= s
->next
)
1559 shutdown(s
->tcpfd
, SHUT_RDWR
);
1563 if (!option_bool(OPT_DEBUG
))
1575 int make_icmp_sock(void)
1580 if ((fd
= socket (AF_INET
, SOCK_RAW
, IPPROTO_ICMP
)) != -1)
1583 setsockopt(fd
, SOL_SOCKET
, SO_DONTROUTE
, &zeroopt
, sizeof(zeroopt
)) == -1)
1593 int icmp_ping(struct in_addr addr
)
1595 /* Try and get an ICMP echo from a machine. */
1597 /* Note that whilst in the three second wait, we check for
1598 (and service) events on the DNS and TFTP sockets, (so doing that
1599 better not use any resources our caller has in use...)
1600 but we remain deaf to signals or further DHCP packets. */
1603 struct sockaddr_in saddr
;
1608 unsigned short id
= rand16();
1613 #if defined(HAVE_LINUX_NETWORK) || defined (HAVE_SOLARIS_NETWORK)
1614 if ((fd
= make_icmp_sock()) == -1)
1618 fd
= daemon
->dhcp_icmp_fd
;
1619 setsockopt(fd
, SOL_SOCKET
, SO_RCVBUF
, &opt
, sizeof(opt
));
1622 saddr
.sin_family
= AF_INET
;
1624 saddr
.sin_addr
= addr
;
1625 #ifdef HAVE_SOCKADDR_SA_LEN
1626 saddr
.sin_len
= sizeof(struct sockaddr_in
);
1629 memset(&packet
.icmp
, 0, sizeof(packet
.icmp
));
1630 packet
.icmp
.icmp_type
= ICMP_ECHO
;
1631 packet
.icmp
.icmp_id
= id
;
1632 for (j
= 0, i
= 0; i
< sizeof(struct icmp
) / 2; i
++)
1633 j
+= ((u16
*)&packet
.icmp
)[i
];
1635 j
= (j
& 0xffff) + (j
>> 16);
1636 packet
.icmp
.icmp_cksum
= (j
== 0xffff) ? j
: ~j
;
1638 while (sendto(fd
, (char *)&packet
.icmp
, sizeof(struct icmp
), 0,
1639 (struct sockaddr
*)&saddr
, sizeof(saddr
)) == -1 &&
1642 for (now
= start
= dnsmasq_time();
1643 difftime(now
, start
) < (float)PING_WAIT
;)
1647 struct sockaddr_in faddr
;
1649 socklen_t len
= sizeof(faddr
);
1651 tv
.tv_usec
= 250000;
1657 set_dns_listeners(now
, &rset
, &maxfd
);
1658 set_log_writer(&wset
, &maxfd
);
1661 if (daemon
->doing_ra
)
1663 FD_SET(daemon
->icmp6fd
, &rset
);
1664 bump_maxfd(daemon
->icmp6fd
, &maxfd
);
1668 if (select(maxfd
+1, &rset
, &wset
, NULL
, &tv
) < 0)
1674 now
= dnsmasq_time();
1676 check_log_writer(&wset
);
1677 check_dns_listeners(&rset
, now
);
1680 if (daemon
->doing_ra
&& FD_ISSET(daemon
->icmp6fd
, &rset
))
1685 check_tftp_listeners(&rset
, now
);
1688 if (FD_ISSET(fd
, &rset
) &&
1689 recvfrom(fd
, &packet
, sizeof(packet
), 0,
1690 (struct sockaddr
*)&faddr
, &len
) == sizeof(packet
) &&
1691 saddr
.sin_addr
.s_addr
== faddr
.sin_addr
.s_addr
&&
1692 packet
.icmp
.icmp_type
== ICMP_ECHOREPLY
&&
1693 packet
.icmp
.icmp_seq
== 0 &&
1694 packet
.icmp
.icmp_id
== id
)
1701 #if defined(HAVE_LINUX_NETWORK) || defined(HAVE_SOLARIS_NETWORK)
1705 setsockopt(fd
, SOL_SOCKET
, SO_RCVBUF
, &opt
, sizeof(opt
));