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 #if defined(HAVE_DHCP) || defined(HAVE_DHCP6)
99 struct dhcp_context
*context
;
100 struct dhcp_relay
*relay
;
104 setlocale(LC_ALL
, "");
105 bindtextdomain("dnsmasq", LOCALEDIR
);
106 textdomain("dnsmasq");
109 sigact
.sa_handler
= sig_handler
;
111 sigemptyset(&sigact
.sa_mask
);
112 sigaction(SIGUSR1
, &sigact
, NULL
);
113 sigaction(SIGUSR2
, &sigact
, NULL
);
114 sigaction(SIGHUP
, &sigact
, NULL
);
115 sigaction(SIGTERM
, &sigact
, NULL
);
116 sigaction(SIGALRM
, &sigact
, NULL
);
117 sigaction(SIGCHLD
, &sigact
, NULL
);
120 sigact
.sa_handler
= SIG_IGN
;
121 sigaction(SIGPIPE
, &sigact
, NULL
);
123 umask(022); /* known umask, create leases and pid files as 0644 */
125 read_opts(argc
, argv
, compile_opts
);
127 if (daemon
->edns_pktsz
< PACKETSZ
)
128 daemon
->edns_pktsz
= PACKETSZ
;
129 daemon
->packet_buff_sz
= daemon
->edns_pktsz
> DNSMASQ_PACKETSZ
?
130 daemon
->edns_pktsz
: DNSMASQ_PACKETSZ
;
131 daemon
->packet
= safe_malloc(daemon
->packet_buff_sz
);
133 daemon
->addrbuff
= safe_malloc(ADDRSTRLEN
);
137 if (!daemon
->lease_file
)
139 if (daemon
->dhcp
|| daemon
->dhcp6
)
140 daemon
->lease_file
= LEASEFILE
;
144 /* Close any file descriptors we inherited apart from std{in|out|err}
146 Ensure that at least stdin, stdout and stderr (fd 0, 1, 2) exist,
147 otherwise file descriptors we create can end up being 0, 1, or 2
148 and then get accidentally closed later when we make 0, 1, and 2
149 open to /dev/null. Normally we'll be started with 0, 1 and 2 open,
150 but it's not guaranteed. By opening /dev/null three times, we
151 ensure that we're not using those fds for real stuff. */
152 for (i
= 0; i
< max_fd
; i
++)
153 if (i
!= STDOUT_FILENO
&& i
!= STDERR_FILENO
&& i
!= STDIN_FILENO
)
156 open("/dev/null", O_RDWR
);
158 #ifndef HAVE_LINUX_NETWORK
159 # if !(defined(IP_RECVDSTADDR) && defined(IP_RECVIF) && defined(IP_SENDSRCADDR))
160 if (!option_bool(OPT_NOWILD
))
163 set_option_bool(OPT_NOWILD
);
167 /* -- bind-dynamic not supported on !Linux, fall back to --bind-interfaces */
168 if (option_bool(OPT_CLEVERBIND
))
171 set_option_bool(OPT_NOWILD
);
172 reset_option_bool(OPT_CLEVERBIND
);
177 if (option_bool(OPT_TFTP
))
178 die(_("TFTP server not available: set HAVE_TFTP in src/config.h"), NULL
, EC_BADCONF
);
181 #ifdef HAVE_CONNTRACK
182 if (option_bool(OPT_CONNTRACK
) && (daemon
->query_port
!= 0 || daemon
->osport
))
183 die (_("Cannot use --conntrack AND --query-port"), NULL
, EC_BADCONF
);
185 if (option_bool(OPT_CONNTRACK
))
186 die(_("Conntrack support not available: set HAVE_CONNTRACK in src/config.h"), NULL
, EC_BADCONF
);
189 #ifdef HAVE_SOLARIS_NETWORK
190 if (daemon
->max_logs
!= 0)
191 die(_("asychronous logging is not available under Solaris"), NULL
, EC_BADCONF
);
195 if (daemon
->max_logs
!= 0)
196 die(_("asychronous logging is not available under Android"), NULL
, EC_BADCONF
);
200 if (daemon
->authserver
)
201 die(_("authoritative DNS not available: set HAVE_AUTH in src/config.h"), NULL
, EC_BADCONF
);
206 now
= dnsmasq_time();
208 /* Create a serial at startup if not configured. */
209 if (daemon
->authinterface
&& daemon
->soa_sn
== 0)
210 #ifdef HAVE_BROKEN_RTC
211 die(_("zone serial must be configured in --auth-soa"), NULL
, EC_BADCONF
);
213 daemon
->soa_sn
= now
;
219 daemon
->doing_ra
= option_bool(OPT_RA
);
221 for (context
= daemon
->dhcp6
; context
; context
= context
->next
)
223 if (context
->flags
& CONTEXT_DHCP
)
224 daemon
->doing_dhcp6
= 1;
225 if (context
->flags
& CONTEXT_RA
)
226 daemon
->doing_ra
= 1;
227 #ifndef HAVE_LINUX_NETWORK
228 if (context
->flags
& CONTEXT_TEMPLATE
)
229 die (_("dhcp-range constructor not available on this platform"), NULL
, EC_BADCONF
);
236 /* Note that order matters here, we must call lease_init before
237 creating any file descriptors which shouldn't be leaked
238 to the lease-script init process. We need to call common_init
239 before lease_init to allocate buffers it uses.*/
240 if (daemon
->dhcp
|| daemon
->doing_dhcp6
|| daemon
->relay4
|| daemon
->relay6
)
243 if (daemon
->dhcp
|| daemon
->doing_dhcp6
)
247 if (daemon
->dhcp
|| daemon
->relay4
)
251 if (daemon
->doing_ra
|| daemon
->doing_dhcp6
|| daemon
->relay6
)
254 if (daemon
->doing_dhcp6
|| daemon
->relay6
)
265 #ifdef HAVE_LINUX_NETWORK
268 if (option_bool(OPT_NOWILD
) && option_bool(OPT_CLEVERBIND
))
269 die(_("cannot set --bind-interfaces and --bind-dynamic"), NULL
, EC_BADCONF
);
272 if (!enumerate_interfaces(1) || !enumerate_interfaces(0))
273 die(_("failed to find list of interfaces: %s"), NULL
, EC_MISC
);
275 if (option_bool(OPT_NOWILD
) || option_bool(OPT_CLEVERBIND
))
277 create_bound_listeners(1);
279 if (!option_bool(OPT_CLEVERBIND
))
280 for (if_tmp
= daemon
->if_names
; if_tmp
; if_tmp
= if_tmp
->next
)
281 if (if_tmp
->name
&& !if_tmp
->used
)
282 die(_("unknown interface %s"), if_tmp
->name
, EC_BADNET
);
284 #if defined(HAVE_LINUX_NETWORK) && defined(HAVE_DHCP)
285 /* after enumerate_interfaces() */
289 bindtodevice(daemon
->dhcpfd
);
290 if (daemon
->enable_pxe
)
291 bindtodevice(daemon
->pxefd
);
295 #if defined(HAVE_LINUX_NETWORK) && defined(HAVE_DHCP6)
296 if (daemon
->doing_dhcp6
&& !daemon
->relay6
)
297 bindtodevice(daemon
->dhcp6fd
);
301 create_wildcard_listeners();
304 /* after enumerate_interfaces() */
305 if (daemon
->doing_dhcp6
|| daemon
->relay6
|| daemon
->doing_ra
)
309 if (daemon
->port
!= 0)
312 if (option_bool(OPT_DBUS
))
317 daemon
->watches
= NULL
;
318 if ((err
= dbus_init()))
319 die(_("DBus error: %s"), err
, EC_MISC
);
322 die(_("DBus not available: set HAVE_DBUS in src/config.h"), NULL
, EC_BADCONF
);
325 if (daemon
->port
!= 0)
328 #if defined(HAVE_SCRIPT)
329 /* Note getpwnam returns static storage */
330 if ((daemon
->dhcp
|| daemon
->dhcp6
) &&
331 daemon
->scriptuser
&&
332 (daemon
->lease_change_command
|| daemon
->luascript
))
334 if ((ent_pw
= getpwnam(daemon
->scriptuser
)))
336 script_uid
= ent_pw
->pw_uid
;
337 script_gid
= ent_pw
->pw_gid
;
340 baduser
= daemon
->scriptuser
;
344 if (daemon
->username
&& !(ent_pw
= getpwnam(daemon
->username
)))
345 baduser
= daemon
->username
;
346 else if (daemon
->groupname
&& !(gp
= getgrnam(daemon
->groupname
)))
347 baduser
= daemon
->groupname
;
350 die(_("unknown user or group: %s"), baduser
, EC_BADCONF
);
352 /* implement group defaults, "dip" if available, or group associated with uid */
353 if (!daemon
->group_set
&& !gp
)
355 if (!(gp
= getgrnam(CHGRP
)) && ent_pw
)
356 gp
= getgrgid(ent_pw
->pw_gid
);
358 /* for error message */
360 daemon
->groupname
= gp
->gr_name
;
363 #if defined(HAVE_LINUX_NETWORK)
364 /* determine capability API version here, while we can still
366 if (ent_pw
&& ent_pw
->pw_uid
!= 0)
368 int capsize
= 1; /* for header version 1 */
369 hdr
= safe_malloc(sizeof(*hdr
));
371 /* find version supported by kernel */
372 memset(hdr
, 0, sizeof(*hdr
));
375 if (hdr
->version
!= LINUX_CAPABILITY_VERSION_1
)
377 /* if unknown version, use largest supported version (3) */
378 if (hdr
->version
!= LINUX_CAPABILITY_VERSION_2
)
379 hdr
->version
= LINUX_CAPABILITY_VERSION_3
;
383 data
= safe_malloc(sizeof(*data
) * capsize
);
384 memset(data
, 0, sizeof(*data
) * capsize
);
388 /* Use a pipe to carry signals and other events back to the event loop
389 in a race-free manner and another to carry errors to daemon-invoking process */
390 safe_pipe(pipefd
, 1);
392 piperead
= pipefd
[0];
393 pipewrite
= pipefd
[1];
394 /* prime the pipe to load stuff first time. */
395 send_event(pipewrite
, EVENT_RELOAD
, 0, NULL
);
399 if (!option_bool(OPT_DEBUG
))
401 /* The following code "daemonizes" the process.
402 See Stevens section 12.4 */
405 die(_("cannot chdir to filesystem root: %s"), NULL
, EC_MISC
);
408 if (!option_bool(OPT_NO_FORK
))
412 /* pipe to carry errors back to original process.
413 When startup is complete we close this and the process terminates. */
414 safe_pipe(err_pipe
, 0);
416 if ((pid
= fork()) == -1)
417 /* fd == -1 since we've not forked, never returns. */
418 send_event(-1, EVENT_FORK_ERR
, errno
, NULL
);
422 struct event_desc ev
;
425 /* close our copy of write-end */
428 /* check for errors after the fork */
429 if (read_event(err_pipe
[0], &ev
, &msg
))
430 fatal_event(&ev
, msg
);
437 /* NO calls to die() from here on. */
441 if ((pid
= fork()) == -1)
442 send_event(err_pipe
[1], EVENT_FORK_ERR
, errno
, NULL
);
449 /* write pidfile _after_ forking ! */
454 sprintf(daemon
->namebuff
, "%d\n", (int) getpid());
456 /* Explanation: Some installations of dnsmasq (eg Debian/Ubuntu) locate the pid-file
457 in a directory which is writable by the non-privileged user that dnsmasq runs as. This
458 allows the daemon to delete the file as part of its shutdown. This is a security hole to the
459 extent that an attacker running as the unprivileged user could replace the pidfile with a
460 symlink, and have the target of that symlink overwritten as root next time dnsmasq starts.
462 The folowing code first deletes any existing file, and then opens it with the O_EXCL flag,
463 ensuring that the open() fails should there be any existing file (because the unlink() failed,
464 or an attacker exploited the race between unlink() and open()). This ensures that no symlink
467 Any compromise of the non-privileged user still theoretically allows the pid-file to be
468 replaced whilst dnsmasq is running. The worst that could allow is that the usual
469 "shutdown dnsmasq" shell command could be tricked into stopping any other process.
471 Note that if dnsmasq is started as non-root (eg for testing) it silently ignores
472 failure to write the pid-file.
475 unlink(daemon
->runfile
);
477 if ((fd
= open(daemon
->runfile
, O_WRONLY
|O_CREAT
|O_TRUNC
|O_EXCL
, S_IWUSR
|S_IRUSR
|S_IRGRP
|S_IROTH
)) == -1)
479 /* only complain if started as root */
485 if (!read_write(fd
, (unsigned char *)daemon
->namebuff
, strlen(daemon
->namebuff
), 0))
488 while (!err
&& close(fd
) == -1)
495 send_event(err_pipe
[1], EVENT_PIDFILE
, errno
, daemon
->runfile
);
501 log_err
= log_start(ent_pw
, err_pipe
[1]);
503 if (!option_bool(OPT_DEBUG
))
505 /* open stdout etc to /dev/null */
506 int nullfd
= open("/dev/null", O_RDWR
);
507 dup2(nullfd
, STDOUT_FILENO
);
508 dup2(nullfd
, STDERR_FILENO
);
509 dup2(nullfd
, STDIN_FILENO
);
513 /* if we are to run scripts, we need to fork a helper before dropping root. */
514 daemon
->helperfd
= -1;
516 if ((daemon
->dhcp
|| daemon
->dhcp6
) && (daemon
->lease_change_command
|| daemon
->luascript
))
517 daemon
->helperfd
= create_helper(pipewrite
, err_pipe
[1], script_uid
, script_gid
, max_fd
);
520 if (!option_bool(OPT_DEBUG
) && getuid() == 0)
522 int bad_capabilities
= 0;
525 /* remove all supplimentary groups */
527 (setgroups(0, &dummy
) == -1 ||
528 setgid(gp
->gr_gid
) == -1))
530 send_event(err_pipe
[1], EVENT_GROUP_ERR
, errno
, daemon
->groupname
);
534 if (ent_pw
&& ent_pw
->pw_uid
!= 0)
536 #if defined(HAVE_LINUX_NETWORK)
537 /* On linux, we keep CAP_NETADMIN (for ARP-injection) and
538 CAP_NET_RAW (for icmp) if we're doing dhcp. If we have yet to bind
539 ports because of DAD, or we're doing it dynamically,
540 we need CAP_NET_BIND_SERVICE too. */
541 if (is_dad_listeners() || option_bool(OPT_CLEVERBIND
))
542 data
->effective
= data
->permitted
= data
->inheritable
=
543 (1 << CAP_NET_ADMIN
) | (1 << CAP_NET_RAW
) |
544 (1 << CAP_SETUID
) | (1 << CAP_NET_BIND_SERVICE
);
546 data
->effective
= data
->permitted
= data
->inheritable
=
547 (1 << CAP_NET_ADMIN
) | (1 << CAP_NET_RAW
) | (1 << CAP_SETUID
);
549 /* Tell kernel to not clear capabilities when dropping root */
550 if (capset(hdr
, data
) == -1 || prctl(PR_SET_KEEPCAPS
, 1, 0, 0, 0) == -1)
551 bad_capabilities
= errno
;
553 #elif defined(HAVE_SOLARIS_NETWORK)
554 /* http://developers.sun.com/solaris/articles/program_privileges.html */
555 priv_set_t
*priv_set
;
557 if (!(priv_set
= priv_str_to_set("basic", ",", NULL
)) ||
558 priv_addset(priv_set
, PRIV_NET_ICMPACCESS
) == -1 ||
559 priv_addset(priv_set
, PRIV_SYS_NET_CONFIG
) == -1)
560 bad_capabilities
= errno
;
562 if (priv_set
&& bad_capabilities
== 0)
564 priv_inverse(priv_set
);
566 if (setppriv(PRIV_OFF
, PRIV_LIMIT
, priv_set
) == -1)
567 bad_capabilities
= errno
;
571 priv_freeset(priv_set
);
575 if (bad_capabilities
!= 0)
577 send_event(err_pipe
[1], EVENT_CAP_ERR
, bad_capabilities
, NULL
);
581 /* finally drop root */
582 if (setuid(ent_pw
->pw_uid
) == -1)
584 send_event(err_pipe
[1], EVENT_USER_ERR
, errno
, daemon
->username
);
588 #ifdef HAVE_LINUX_NETWORK
589 if (is_dad_listeners() || option_bool(OPT_CLEVERBIND
))
590 data
->effective
= data
->permitted
=
591 (1 << CAP_NET_ADMIN
) | (1 << CAP_NET_RAW
) | (1 << CAP_NET_BIND_SERVICE
);
593 data
->effective
= data
->permitted
=
594 (1 << CAP_NET_ADMIN
) | (1 << CAP_NET_RAW
);
595 data
->inheritable
= 0;
597 /* lose the setuid and setgid capbilities */
598 if (capset(hdr
, data
) == -1)
600 send_event(err_pipe
[1], EVENT_CAP_ERR
, errno
, NULL
);
608 #ifdef HAVE_LINUX_NETWORK
609 if (option_bool(OPT_DEBUG
))
610 prctl(PR_SET_DUMPABLE
, 1, 0, 0, 0);
614 if (option_bool(OPT_TFTP
))
617 struct tftp_prefix
*p
;
619 if (daemon
->tftp_prefix
)
621 if (!((dir
= opendir(daemon
->tftp_prefix
))))
623 send_event(err_pipe
[1], EVENT_TFTP_ERR
, errno
, daemon
->tftp_prefix
);
629 for (p
= daemon
->if_prefix
; p
; p
= p
->next
)
631 if (!((dir
= opendir(p
->prefix
))))
633 send_event(err_pipe
[1], EVENT_TFTP_ERR
, errno
, p
->prefix
);
641 if (daemon
->port
== 0)
642 my_syslog(LOG_INFO
, _("started, version %s DNS disabled"), VERSION
);
643 else if (daemon
->cachesize
!= 0)
644 my_syslog(LOG_INFO
, _("started, version %s cachesize %d"), VERSION
, daemon
->cachesize
);
646 my_syslog(LOG_INFO
, _("started, version %s cache disabled"), VERSION
);
648 my_syslog(LOG_INFO
, _("compile time options: %s"), compile_opts
);
651 if (option_bool(OPT_DBUS
))
654 my_syslog(LOG_INFO
, _("DBus support enabled: connected to system bus"));
656 my_syslog(LOG_INFO
, _("DBus support enabled: bus connection pending"));
661 my_syslog(LOG_WARNING
, _("warning: failed to change owner of %s: %s"),
662 daemon
->log_file
, strerror(log_err
));
665 my_syslog(LOG_WARNING
, _("setting --bind-interfaces option because of OS limitations"));
667 if (!option_bool(OPT_NOWILD
))
668 for (if_tmp
= daemon
->if_names
; if_tmp
; if_tmp
= if_tmp
->next
)
669 if (if_tmp
->name
&& !if_tmp
->used
)
670 my_syslog(LOG_WARNING
, _("warning: interface %s does not currently exist"), if_tmp
->name
);
672 if (daemon
->port
!= 0 && option_bool(OPT_NO_RESOLV
))
674 if (daemon
->resolv_files
&& !daemon
->resolv_files
->is_default
)
675 my_syslog(LOG_WARNING
, _("warning: ignoring resolv-file flag because no-resolv is set"));
676 daemon
->resolv_files
= NULL
;
677 if (!daemon
->servers
)
678 my_syslog(LOG_WARNING
, _("warning: no upstream servers configured"));
681 if (daemon
->max_logs
!= 0)
682 my_syslog(LOG_INFO
, _("asynchronous logging enabled, queue limit is %d messages"), daemon
->max_logs
);
686 for (context
= daemon
->dhcp
; context
; context
= context
->next
)
687 log_context(AF_INET
, context
);
689 for (relay
= daemon
->relay4
; relay
; relay
= relay
->next
)
690 log_relay(AF_INET
, relay
);
693 for (context
= daemon
->dhcp6
; context
; context
= context
->next
)
694 log_context(AF_INET6
, context
);
696 for (relay
= daemon
->relay6
; relay
; relay
= relay
->next
)
697 log_relay(AF_INET6
, relay
);
699 if (daemon
->doing_dhcp6
|| daemon
->doing_ra
)
700 dhcp_construct_contexts(now
);
702 if (option_bool(OPT_RA
))
703 my_syslog(MS_DHCP
| LOG_INFO
, _("IPv6 router advertisement enabled"));
706 /* after dhcp_contruct_contexts */
707 if (daemon
->dhcp
|| daemon
->doing_dhcp6
)
708 lease_find_interfaces(now
);
712 if (option_bool(OPT_TFTP
))
715 if (FD_SETSIZE
< (unsigned)max_fd
)
719 my_syslog(MS_TFTP
| LOG_INFO
, "TFTP %s%s %s",
720 daemon
->tftp_prefix
? _("root is ") : _("enabled"),
721 daemon
->tftp_prefix
? daemon
->tftp_prefix
: "",
722 option_bool(OPT_TFTP_SECURE
) ? _("secure mode") : "");
724 /* This is a guess, it assumes that for small limits,
725 disjoint files might be served, but for large limits,
726 a single file will be sent to may clients (the file only needs
729 max_fd
-= 30; /* use other than TFTP */
733 else if (max_fd
< 100)
736 max_fd
= max_fd
- 20;
738 /* if we have to use a limited range of ports,
739 that will limit the number of transfers */
740 if (daemon
->start_tftp_port
!= 0 &&
741 daemon
->end_tftp_port
- daemon
->start_tftp_port
+ 1 < max_fd
)
742 max_fd
= daemon
->end_tftp_port
- daemon
->start_tftp_port
+ 1;
744 if (daemon
->tftp_max
> max_fd
)
746 daemon
->tftp_max
= max_fd
;
747 my_syslog(MS_TFTP
| LOG_WARNING
,
748 _("restricting maximum simultaneous TFTP transfers to %d"),
754 /* finished start-up - release original process */
755 if (err_pipe
[1] != -1)
758 if (daemon
->port
!= 0)
766 struct timeval t
, *tp
= NULL
;
767 fd_set rset
, wset
, eset
;
773 /* if we are out of resources, find how long we have to wait
774 for some to come free, we'll loop around then and restart
775 listening for queries */
776 if ((t
.tv_sec
= set_dns_listeners(now
, &rset
, &maxfd
)) != 0)
782 /* Whilst polling for the dbus, or doing a tftp transfer, wake every quarter second */
783 if (daemon
->tftp_trans
||
784 (option_bool(OPT_DBUS
) && !daemon
->dbus
))
790 /* Wake every second whilst waiting for DAD to complete */
791 else if (is_dad_listeners())
799 set_dbus_listeners(&maxfd
, &rset
, &wset
, &eset
);
803 if (daemon
->dhcp
|| daemon
->relay4
)
805 FD_SET(daemon
->dhcpfd
, &rset
);
806 bump_maxfd(daemon
->dhcpfd
, &maxfd
);
807 if (daemon
->pxefd
!= -1)
809 FD_SET(daemon
->pxefd
, &rset
);
810 bump_maxfd(daemon
->pxefd
, &maxfd
);
816 if (daemon
->doing_dhcp6
|| daemon
->relay6
)
818 FD_SET(daemon
->dhcp6fd
, &rset
);
819 bump_maxfd(daemon
->dhcp6fd
, &maxfd
);
822 if (daemon
->doing_ra
)
824 FD_SET(daemon
->icmp6fd
, &rset
);
825 bump_maxfd(daemon
->icmp6fd
, &maxfd
);
829 #ifdef HAVE_LINUX_NETWORK
830 FD_SET(daemon
->netlinkfd
, &rset
);
831 bump_maxfd(daemon
->netlinkfd
, &maxfd
);
834 FD_SET(piperead
, &rset
);
835 bump_maxfd(piperead
, &maxfd
);
839 while (helper_buf_empty() && do_script_run(now
));
842 while (helper_buf_empty() && do_tftp_script_run());
845 if (!helper_buf_empty())
847 FD_SET(daemon
->helperfd
, &wset
);
848 bump_maxfd(daemon
->helperfd
, &maxfd
);
851 /* need this for other side-effects */
852 while (do_script_run(now
));
855 while (do_tftp_script_run());
861 /* must do this just before select(), when we know no
862 more calls to my_syslog() can occur */
863 set_log_writer(&wset
, &maxfd
);
865 if (select(maxfd
+1, &rset
, &wset
, &eset
, tp
) < 0)
867 /* otherwise undefined after error */
868 FD_ZERO(&rset
); FD_ZERO(&wset
); FD_ZERO(&eset
);
871 now
= dnsmasq_time();
873 check_log_writer(&wset
);
876 enumerate_interfaces(1);
878 /* Check the interfaces to see if any have exited DAD state
879 and if so, bind the address. */
880 if (is_dad_listeners())
882 enumerate_interfaces(0);
883 /* NB, is_dad_listeners() == 1 --> we're binding interfaces */
884 create_bound_listeners(0);
887 #ifdef HAVE_LINUX_NETWORK
888 if (FD_ISSET(daemon
->netlinkfd
, &rset
))
889 netlink_multicast(now
);
892 /* Check for changes to resolv files once per second max. */
893 /* Don't go silent for long periods if the clock goes backwards. */
894 if (daemon
->last_resolv
== 0 ||
895 difftime(now
, daemon
->last_resolv
) > 1.0 ||
896 difftime(now
, daemon
->last_resolv
) < -1.0)
898 /* poll_resolv doesn't need to reload first time through, since
899 that's queued anyway. */
901 poll_resolv(0, daemon
->last_resolv
!= 0, now
);
902 daemon
->last_resolv
= now
;
905 if (FD_ISSET(piperead
, &rset
))
906 async_event(piperead
, now
);
909 /* if we didn't create a DBus connection, retry now. */
910 if (option_bool(OPT_DBUS
) && !daemon
->dbus
)
913 if ((err
= dbus_init()))
914 my_syslog(LOG_WARNING
, _("DBus error: %s"), err
);
916 my_syslog(LOG_INFO
, _("connected to system DBus"));
918 check_dbus_listeners(&rset
, &wset
, &eset
);
921 check_dns_listeners(&rset
, now
);
924 check_tftp_listeners(&rset
, now
);
928 if (daemon
->dhcp
|| daemon
->relay4
)
930 if (FD_ISSET(daemon
->dhcpfd
, &rset
))
932 if (daemon
->pxefd
!= -1 && FD_ISSET(daemon
->pxefd
, &rset
))
937 if ((daemon
->doing_dhcp6
|| daemon
->relay6
) && FD_ISSET(daemon
->dhcp6fd
, &rset
))
940 if (daemon
->doing_ra
&& FD_ISSET(daemon
->icmp6fd
, &rset
))
945 if (daemon
->helperfd
!= -1 && FD_ISSET(daemon
->helperfd
, &wset
))
953 static void sig_handler(int sig
)
957 /* ignore anything other than TERM during startup
958 and in helper proc. (helper ignore TERM too) */
962 else if (pid
!= getpid())
964 /* alarm is used to kill TCP children after a fixed time. */
971 int event
, errsave
= errno
;
974 event
= EVENT_RELOAD
;
975 else if (sig
== SIGCHLD
)
977 else if (sig
== SIGALRM
)
979 else if (sig
== SIGTERM
)
981 else if (sig
== SIGUSR1
)
983 else if (sig
== SIGUSR2
)
984 event
= EVENT_REOPEN
;
988 send_event(pipewrite
, event
, 0, NULL
);
993 /* now == 0 -> queue immediate callback */
994 void send_alarm(time_t event
, time_t now
)
996 if (now
== 0 || event
!= 0)
998 /* alarm(0) or alarm(-ve) doesn't do what we want.... */
999 if ((now
== 0 || difftime(event
, now
) <= 0.0))
1000 send_event(pipewrite
, EVENT_ALARM
, 0, NULL
);
1002 alarm((unsigned)difftime(event
, now
));
1006 void send_event(int fd
, int event
, int data
, char *msg
)
1008 struct event_desc ev
;
1009 struct iovec iov
[2];
1013 ev
.msg_sz
= msg
? strlen(msg
) : 0;
1015 iov
[0].iov_base
= &ev
;
1016 iov
[0].iov_len
= sizeof(ev
);
1017 iov
[1].iov_base
= msg
;
1018 iov
[1].iov_len
= ev
.msg_sz
;
1020 /* error pipe, debug mode. */
1022 fatal_event(&ev
, msg
);
1024 /* pipe is non-blocking and struct event_desc is smaller than
1025 PIPE_BUF, so this either fails or writes everything */
1026 while (writev(fd
, iov
, msg
? 2 : 1) == -1 && errno
== EINTR
);
1029 /* NOTE: the memory used to return msg is leaked: use msgs in events only
1030 to describe fatal errors. */
1031 static int read_event(int fd
, struct event_desc
*evp
, char **msg
)
1035 if (!read_write(fd
, (unsigned char *)evp
, sizeof(struct event_desc
), 1))
1040 if (evp
->msg_sz
!= 0 &&
1041 (buf
= malloc(evp
->msg_sz
+ 1)) &&
1042 read_write(fd
, (unsigned char *)buf
, evp
->msg_sz
, 1))
1044 buf
[evp
->msg_sz
] = 0;
1051 static void fatal_event(struct event_desc
*ev
, char *msg
)
1060 case EVENT_FORK_ERR
:
1061 die(_("cannot fork into background: %s"), NULL
, EC_MISC
);
1063 case EVENT_PIPE_ERR
:
1064 die(_("failed to create helper: %s"), NULL
, EC_MISC
);
1067 die(_("setting capabilities failed: %s"), NULL
, EC_MISC
);
1069 case EVENT_USER_ERR
:
1070 die(_("failed to change user-id to %s: %s"), msg
, EC_MISC
);
1072 case EVENT_GROUP_ERR
:
1073 die(_("failed to change group-id to %s: %s"), msg
, EC_MISC
);
1076 die(_("failed to open pidfile %s: %s"), msg
, EC_FILE
);
1079 die(_("cannot open log %s: %s"), msg
, EC_FILE
);
1082 die(_("failed to load Lua script: %s"), msg
, EC_MISC
);
1084 case EVENT_TFTP_ERR
:
1085 die(_("TFTP directory %s inaccessible: %s"), msg
, EC_FILE
);
1089 static void async_event(int pipe
, time_t now
)
1092 struct event_desc ev
;
1096 /* NOTE: the memory used to return msg is leaked: use msgs in events only
1097 to describe fatal errors. */
1099 if (read_event(pipe
, &ev
, &msg
))
1103 clear_cache_and_reload(now
);
1104 if (daemon
->port
!= 0 && daemon
->resolv_files
&& option_bool(OPT_NO_POLL
))
1106 reload_servers(daemon
->resolv_files
->name
);
1115 if (daemon
->port
!= 0)
1121 if (daemon
->dhcp
|| daemon
->doing_dhcp6
)
1123 lease_prune(NULL
, now
);
1124 lease_update_file(now
);
1127 else if (daemon
->doing_ra
)
1128 /* Not doing DHCP, so no lease system, manage alarms for ra only */
1129 send_alarm(periodic_ra(now
), now
);
1135 /* See Stevens 5.10 */
1136 while ((p
= waitpid(-1, NULL
, WNOHANG
)) != 0)
1143 for (i
= 0 ; i
< MAX_PROCS
; i
++)
1144 if (daemon
->tcp_pids
[i
] == p
)
1145 daemon
->tcp_pids
[i
] = 0;
1149 my_syslog(LOG_WARNING
, _("script process killed by signal %d"), ev
.data
);
1153 my_syslog(LOG_WARNING
, _("script process exited with status %d"), ev
.data
);
1156 case EVENT_EXEC_ERR
:
1157 my_syslog(LOG_ERR
, _("failed to execute %s: %s"),
1158 daemon
->lease_change_command
, strerror(ev
.data
));
1161 /* necessary for fatal errors in helper */
1162 case EVENT_USER_ERR
:
1165 fatal_event(&ev
, msg
);
1169 /* Note: this may leave TCP-handling processes with the old file still open.
1170 Since any such process will die in CHILD_LIFETIME or probably much sooner,
1171 we leave them logging to the old file. */
1172 if (daemon
->log_file
!= NULL
)
1173 log_reopen(daemon
->log_file
);
1176 tomato_helper(now
); //possibly delete & write out leases for tomato
1178 /* following is Asus tweak. Interestingly Asus read the dnsmasq leases db
1179 directly. They signal dnsmasq to update via SIGUSR2 and wait 1 second
1180 assuming the file will be complete by the time they come to parse it.
1181 Race conditions anyone? What if dnsmasq happens to be updating the
1183 #if defined(HAVE_DHCP) && defined(HAVE_LEASEFILE_EXPIRE) && !defined(HAVE_TOMATO)
1184 if (daemon
->dhcp
|| daemon
->dhcp6
)
1185 flush_lease_file(now
);
1190 /* Knock all our children on the head. */
1191 for (i
= 0; i
< MAX_PROCS
; i
++)
1192 if (daemon
->tcp_pids
[i
] != 0)
1193 kill(daemon
->tcp_pids
[i
], SIGALRM
);
1195 #if defined(HAVE_SCRIPT)
1196 /* handle pending lease transitions */
1197 if (daemon
->helperfd
!= -1)
1199 /* block in writes until all done */
1200 if ((i
= fcntl(daemon
->helperfd
, F_GETFL
)) != -1)
1201 fcntl(daemon
->helperfd
, F_SETFL
, i
& ~O_NONBLOCK
);
1204 } while (!helper_buf_empty() || do_script_run(now
));
1205 close(daemon
->helperfd
);
1209 //Originally TOMATO tweak
1210 #if defined(HAVE_DHCP) && defined(HAVE_LEASEFILE_EXPIRE)
1211 if (daemon
->dhcp
|| daemon
->dhcp6
)
1212 flush_lease_file(now
);
1215 if (daemon
->lease_stream
)
1216 fclose(daemon
->lease_stream
);
1218 if (daemon
->runfile
)
1219 unlink(daemon
->runfile
);
1221 my_syslog(LOG_INFO
, _("exiting on receipt of SIGTERM"));
1227 void poll_resolv(int force
, int do_reload
, time_t now
)
1229 struct resolvc
*res
, *latest
;
1230 struct stat statbuf
;
1231 time_t last_change
= 0;
1232 /* There may be more than one possible file.
1233 Go through and find the one which changed _last_.
1234 Warn of any which can't be read. */
1236 if (daemon
->port
== 0 || option_bool(OPT_NO_POLL
))
1239 for (latest
= NULL
, res
= daemon
->resolv_files
; res
; res
= res
->next
)
1240 if (stat(res
->name
, &statbuf
) == -1)
1249 my_syslog(LOG_WARNING
, _("failed to access %s: %s"), res
->name
, strerror(errno
));
1252 if (res
->mtime
!= 0)
1254 /* existing file evaporated, force selection of the latest
1255 file even if its mtime hasn't changed since we last looked */
1256 poll_resolv(1, do_reload
, now
);
1263 if (force
|| (statbuf
.st_mtime
!= res
->mtime
))
1265 res
->mtime
= statbuf
.st_mtime
;
1266 if (difftime(statbuf
.st_mtime
, last_change
) > 0.0)
1268 last_change
= statbuf
.st_mtime
;
1276 static int warned
= 0;
1277 if (reload_servers(latest
->name
))
1279 my_syslog(LOG_INFO
, _("reading %s"), latest
->name
);
1282 if (option_bool(OPT_RELOAD
) && do_reload
)
1283 clear_cache_and_reload(now
);
1290 my_syslog(LOG_WARNING
, _("no servers found in %s, will retry"), latest
->name
);
1297 void clear_cache_and_reload(time_t now
)
1301 if (daemon
->port
!= 0)
1305 if (daemon
->dhcp
|| daemon
->doing_dhcp6
)
1307 if (option_bool(OPT_ETHERS
))
1310 dhcp_update_configs(daemon
->dhcp_conf
);
1311 lease_update_from_configs();
1312 lease_update_file(now
);
1313 lease_update_dns(1);
1316 else if (daemon
->doing_ra
)
1317 /* Not doing DHCP, so no lease system, manage
1318 alarms for ra only */
1319 send_alarm(periodic_ra(now
), now
);
1324 static int set_dns_listeners(time_t now
, fd_set
*set
, int *maxfdp
)
1326 struct serverfd
*serverfdp
;
1327 struct listener
*listener
;
1332 struct tftp_transfer
*transfer
;
1333 for (transfer
= daemon
->tftp_trans
; transfer
; transfer
= transfer
->next
)
1336 FD_SET(transfer
->sockfd
, set
);
1337 bump_maxfd(transfer
->sockfd
, maxfdp
);
1341 /* will we be able to get memory? */
1342 if (daemon
->port
!= 0)
1343 get_new_frec(now
, &wait
);
1345 for (serverfdp
= daemon
->sfds
; serverfdp
; serverfdp
= serverfdp
->next
)
1347 FD_SET(serverfdp
->fd
, set
);
1348 bump_maxfd(serverfdp
->fd
, maxfdp
);
1351 if (daemon
->port
!= 0 && !daemon
->osport
)
1352 for (i
= 0; i
< RANDOM_SOCKS
; i
++)
1353 if (daemon
->randomsocks
[i
].refcount
!= 0)
1355 FD_SET(daemon
->randomsocks
[i
].fd
, set
);
1356 bump_maxfd(daemon
->randomsocks
[i
].fd
, maxfdp
);
1359 for (listener
= daemon
->listeners
; listener
; listener
= listener
->next
)
1361 /* only listen for queries if we have resources */
1362 if (listener
->fd
!= -1 && wait
== 0)
1364 FD_SET(listener
->fd
, set
);
1365 bump_maxfd(listener
->fd
, maxfdp
);
1368 /* death of a child goes through the select loop, so
1369 we don't need to explicitly arrange to wake up here */
1370 if (listener
->tcpfd
!= -1)
1371 for (i
= 0; i
< MAX_PROCS
; i
++)
1372 if (daemon
->tcp_pids
[i
] == 0)
1374 FD_SET(listener
->tcpfd
, set
);
1375 bump_maxfd(listener
->tcpfd
, maxfdp
);
1380 if (tftp
<= daemon
->tftp_max
&& listener
->tftpfd
!= -1)
1382 FD_SET(listener
->tftpfd
, set
);
1383 bump_maxfd(listener
->tftpfd
, maxfdp
);
1392 static void check_dns_listeners(fd_set
*set
, time_t now
)
1394 struct serverfd
*serverfdp
;
1395 struct listener
*listener
;
1398 for (serverfdp
= daemon
->sfds
; serverfdp
; serverfdp
= serverfdp
->next
)
1399 if (FD_ISSET(serverfdp
->fd
, set
))
1400 reply_query(serverfdp
->fd
, serverfdp
->source_addr
.sa
.sa_family
, now
);
1402 if (daemon
->port
!= 0 && !daemon
->osport
)
1403 for (i
= 0; i
< RANDOM_SOCKS
; i
++)
1404 if (daemon
->randomsocks
[i
].refcount
!= 0 &&
1405 FD_ISSET(daemon
->randomsocks
[i
].fd
, set
))
1406 reply_query(daemon
->randomsocks
[i
].fd
, daemon
->randomsocks
[i
].family
, now
);
1408 for (listener
= daemon
->listeners
; listener
; listener
= listener
->next
)
1410 if (listener
->fd
!= -1 && FD_ISSET(listener
->fd
, set
))
1411 receive_query(listener
, now
);
1414 if (listener
->tftpfd
!= -1 && FD_ISSET(listener
->tftpfd
, set
))
1415 tftp_request(listener
, now
);
1418 if (listener
->tcpfd
!= -1 && FD_ISSET(listener
->tcpfd
, set
))
1420 int confd
, client_ok
= 1;
1421 struct irec
*iface
= NULL
;
1423 union mysockaddr tcp_addr
;
1424 socklen_t tcp_len
= sizeof(union mysockaddr
);
1426 while ((confd
= accept(listener
->tcpfd
, NULL
, NULL
)) == -1 && errno
== EINTR
);
1431 if (getsockname(confd
, (struct sockaddr
*)&tcp_addr
, &tcp_len
) == -1)
1437 /* Make sure that the interface list is up-to-date.
1439 We do this here as we may need the results below, and
1440 the DNS code needs them for --interface-name stuff.
1442 Multiple calls to enumerate_interfaces() per select loop are
1443 inhibited, so calls to it in the child process (which doesn't select())
1444 have no effect. This avoids two processes reading from the same
1445 netlink fd and screwing the pooch entirely.
1448 enumerate_interfaces(0);
1450 if (option_bool(OPT_NOWILD
))
1451 iface
= listener
->iface
; /* May be NULL */
1455 char intr_name
[IF_NAMESIZE
];
1457 /* if we can find the arrival interface, check it's one that's allowed */
1458 if ((if_index
= tcp_interface(confd
, tcp_addr
.sa
.sa_family
)) != 0 &&
1459 indextoname(listener
->tcpfd
, if_index
, intr_name
))
1461 struct all_addr addr
;
1462 addr
.addr
.addr4
= tcp_addr
.in
.sin_addr
;
1464 if (tcp_addr
.sa
.sa_family
== AF_INET6
)
1465 addr
.addr
.addr6
= tcp_addr
.in6
.sin6_addr
;
1468 for (iface
= daemon
->interfaces
; iface
; iface
= iface
->next
)
1469 if (iface
->index
== if_index
)
1472 if (!iface
&& !loopback_exception(listener
->tcpfd
, tcp_addr
.sa
.sa_family
, &addr
, intr_name
))
1476 if (option_bool(OPT_CLEVERBIND
))
1477 iface
= listener
->iface
; /* May be NULL */
1480 /* Check for allowed interfaces when binding the wildcard address:
1481 we do this by looking for an interface with the same address as
1482 the local address of the TCP connection, then looking to see if that's
1483 an allowed interface. As a side effect, we get the netmask of the
1484 interface too, for localisation. */
1486 for (iface
= daemon
->interfaces
; iface
; iface
= iface
->next
)
1487 if (sockaddr_isequal(&iface
->addr
, &tcp_addr
))
1497 shutdown(confd
, SHUT_RDWR
);
1501 else if (!option_bool(OPT_DEBUG
) && (p
= fork()) != 0)
1506 for (i
= 0; i
< MAX_PROCS
; i
++)
1507 if (daemon
->tcp_pids
[i
] == 0)
1509 daemon
->tcp_pids
[i
] = p
;
1518 unsigned char *buff
;
1521 struct in_addr netmask
;
1526 netmask
= iface
->netmask
;
1527 auth_dns
= iface
->dns_auth
;
1536 /* Arrange for SIGALARM after CHILD_LIFETIME seconds to
1537 terminate the process. */
1538 if (!option_bool(OPT_DEBUG
))
1539 alarm(CHILD_LIFETIME
);
1542 /* start with no upstream connections. */
1543 for (s
= daemon
->servers
; s
; s
= s
->next
)
1546 /* The connected socket inherits non-blocking
1547 attribute from the listening socket.
1549 if ((flags
= fcntl(confd
, F_GETFL
, 0)) != -1)
1550 fcntl(confd
, F_SETFL
, flags
& ~O_NONBLOCK
);
1552 buff
= tcp_request(confd
, now
, &tcp_addr
, netmask
, auth_dns
);
1554 shutdown(confd
, SHUT_RDWR
);
1560 for (s
= daemon
->servers
; s
; s
= s
->next
)
1563 shutdown(s
->tcpfd
, SHUT_RDWR
);
1567 if (!option_bool(OPT_DEBUG
))
1579 int make_icmp_sock(void)
1584 if ((fd
= socket (AF_INET
, SOCK_RAW
, IPPROTO_ICMP
)) != -1)
1587 setsockopt(fd
, SOL_SOCKET
, SO_DONTROUTE
, &zeroopt
, sizeof(zeroopt
)) == -1)
1597 int icmp_ping(struct in_addr addr
)
1599 /* Try and get an ICMP echo from a machine. */
1601 /* Note that whilst in the three second wait, we check for
1602 (and service) events on the DNS and TFTP sockets, (so doing that
1603 better not use any resources our caller has in use...)
1604 but we remain deaf to signals or further DHCP packets. */
1607 struct sockaddr_in saddr
;
1612 unsigned short id
= rand16();
1617 #if defined(HAVE_LINUX_NETWORK) || defined (HAVE_SOLARIS_NETWORK)
1618 if ((fd
= make_icmp_sock()) == -1)
1622 fd
= daemon
->dhcp_icmp_fd
;
1623 setsockopt(fd
, SOL_SOCKET
, SO_RCVBUF
, &opt
, sizeof(opt
));
1626 saddr
.sin_family
= AF_INET
;
1628 saddr
.sin_addr
= addr
;
1629 #ifdef HAVE_SOCKADDR_SA_LEN
1630 saddr
.sin_len
= sizeof(struct sockaddr_in
);
1633 memset(&packet
.icmp
, 0, sizeof(packet
.icmp
));
1634 packet
.icmp
.icmp_type
= ICMP_ECHO
;
1635 packet
.icmp
.icmp_id
= id
;
1636 for (j
= 0, i
= 0; i
< sizeof(struct icmp
) / 2; i
++)
1637 j
+= ((u16
*)&packet
.icmp
)[i
];
1639 j
= (j
& 0xffff) + (j
>> 16);
1640 packet
.icmp
.icmp_cksum
= (j
== 0xffff) ? j
: ~j
;
1642 while (sendto(fd
, (char *)&packet
.icmp
, sizeof(struct icmp
), 0,
1643 (struct sockaddr
*)&saddr
, sizeof(saddr
)) == -1 &&
1646 for (now
= start
= dnsmasq_time();
1647 difftime(now
, start
) < (float)PING_WAIT
;)
1651 struct sockaddr_in faddr
;
1653 socklen_t len
= sizeof(faddr
);
1655 tv
.tv_usec
= 250000;
1661 set_dns_listeners(now
, &rset
, &maxfd
);
1662 set_log_writer(&wset
, &maxfd
);
1665 if (daemon
->doing_ra
)
1667 FD_SET(daemon
->icmp6fd
, &rset
);
1668 bump_maxfd(daemon
->icmp6fd
, &maxfd
);
1672 if (select(maxfd
+1, &rset
, &wset
, NULL
, &tv
) < 0)
1678 now
= dnsmasq_time();
1680 check_log_writer(&wset
);
1681 check_dns_listeners(&rset
, now
);
1684 if (daemon
->doing_ra
&& FD_ISSET(daemon
->icmp6fd
, &rset
))
1689 check_tftp_listeners(&rset
, now
);
1692 if (FD_ISSET(fd
, &rset
) &&
1693 recvfrom(fd
, &packet
, sizeof(packet
), 0,
1694 (struct sockaddr
*)&faddr
, &len
) == sizeof(packet
) &&
1695 saddr
.sin_addr
.s_addr
== faddr
.sin_addr
.s_addr
&&
1696 packet
.icmp
.icmp_type
== ICMP_ECHOREPLY
&&
1697 packet
.icmp
.icmp_seq
== 0 &&
1698 packet
.icmp
.icmp_id
== id
)
1705 #if defined(HAVE_LINUX_NETWORK) || defined(HAVE_SOLARIS_NETWORK)
1709 setsockopt(fd
, SOL_SOCKET
, SO_RCVBUF
, &opt
, sizeof(opt
));