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path: root/networking/ifplugd.c (plain)
blob: b578f4c61c3ef6ec17ea4cf14aae3cf177c6e7ad
1/* vi: set sw=4 ts=4: */
2/*
3 * ifplugd for busybox, based on ifplugd 0.28 (written by Lennart Poettering).
4 *
5 * Copyright (C) 2009 Maksym Kryzhanovskyy <xmaks@email.cz>
6 *
7 * Licensed under GPLv2 or later, see file LICENSE in this source tree.
8 */
9
10//usage:#define ifplugd_trivial_usage
11//usage: "[OPTIONS]"
12//usage:#define ifplugd_full_usage "\n\n"
13//usage: "Network interface plug detection daemon\n"
14//usage: "\n -n Don't daemonize"
15//usage: "\n -s Don't log to syslog"
16//usage: "\n -i IFACE Interface"
17//usage: "\n -f/-F Treat link detection error as link down/link up"
18//usage: "\n (otherwise exit on error)"
19//usage: "\n -a Don't up interface at each link probe"
20//usage: "\n -M Monitor creation/destruction of interface"
21//usage: "\n (otherwise it must exist)"
22//usage: "\n -r PROG Script to run"
23//usage: "\n -x ARG Extra argument for script"
24//usage: "\n -I Don't exit on nonzero exit code from script"
25//usage: "\n -p Don't run \"up\" script on startup"
26//usage: "\n -q Don't run \"down\" script on exit"
27//usage: "\n -l Always run script on startup"
28//usage: "\n -t SECS Poll time in seconds"
29//usage: "\n -u SECS Delay before running script after link up"
30//usage: "\n -d SECS Delay after link down"
31//usage: "\n -m MODE API mode (mii, priv, ethtool, wlan, iff, auto)"
32//usage: "\n -k Kill running daemon"
33
34#include "libbb.h"
35
36#include "fix_u32.h"
37#include <linux/if.h>
38#include <linux/mii.h>
39#include <linux/ethtool.h>
40#ifdef HAVE_NET_ETHERNET_H
41# include <net/ethernet.h>
42#endif
43#include <linux/netlink.h>
44#include <linux/rtnetlink.h>
45#include <linux/sockios.h>
46#include <syslog.h>
47
48#define __user
49#include <linux/wireless.h>
50
51/*
52From initial port to busybox, removed most of the redundancy by
53converting implementation of a polymorphic interface to the strict
54functional style. The main role is run a script when link state
55changed, other activities like audio signal or detailed reports
56are on the script itself.
57
58One questionable point of the design is netlink usage:
59
60We have 1 second timeout by default to poll the link status,
61it is short enough so that there are no real benefits in
62using netlink to get "instantaneous" interface creation/deletion
63notifications. We can check for interface existence by just
64doing some fast ioctl using its name.
65
66Netlink code then can be just dropped (1k or more?)
67*/
68
69
70#define IFPLUGD_ENV_PREVIOUS "IFPLUGD_PREVIOUS"
71#define IFPLUGD_ENV_CURRENT "IFPLUGD_CURRENT"
72
73enum {
74 FLAG_NO_AUTO = 1 << 0, // -a, Do not enable interface automatically
75 FLAG_NO_DAEMON = 1 << 1, // -n, Do not daemonize
76 FLAG_NO_SYSLOG = 1 << 2, // -s, Do not use syslog, use stderr instead
77 FLAG_IGNORE_FAIL = 1 << 3, // -f, Ignore detection failure, retry instead (failure is treated as DOWN)
78 FLAG_IGNORE_FAIL_POSITIVE = 1 << 4, // -F, Ignore detection failure, retry instead (failure is treated as UP)
79 FLAG_IFACE = 1 << 5, // -i, Specify ethernet interface
80 FLAG_RUN = 1 << 6, // -r, Specify program to execute
81 FLAG_IGNORE_RETVAL = 1 << 7, // -I, Don't exit on nonzero return value of program executed
82 FLAG_POLL_TIME = 1 << 8, // -t, Specify poll time in seconds
83 FLAG_DELAY_UP = 1 << 9, // -u, Specify delay for configuring interface
84 FLAG_DELAY_DOWN = 1 << 10, // -d, Specify delay for deconfiguring interface
85 FLAG_API_MODE = 1 << 11, // -m, Force API mode (mii, priv, ethtool, wlan, auto)
86 FLAG_NO_STARTUP = 1 << 12, // -p, Don't run script on daemon startup
87 FLAG_NO_SHUTDOWN = 1 << 13, // -q, Don't run script on daemon quit
88 FLAG_INITIAL_DOWN = 1 << 14, // -l, Run "down" script on startup if no cable is detected
89 FLAG_EXTRA_ARG = 1 << 15, // -x, Specify an extra argument for action script
90 FLAG_MONITOR = 1 << 16, // -M, Use interface monitoring
91#if ENABLE_FEATURE_PIDFILE
92 FLAG_KILL = 1 << 17, // -k, Kill a running daemon
93#endif
94};
95#if ENABLE_FEATURE_PIDFILE
96# define OPTION_STR "+ansfFi:r:It:u:d:m:pqlx:Mk"
97#else
98# define OPTION_STR "+ansfFi:r:It:u:d:m:pqlx:M"
99#endif
100
101enum { // interface status
102 IFSTATUS_ERR = -1,
103 IFSTATUS_DOWN = 0,
104 IFSTATUS_UP = 1,
105};
106
107enum { // constant fds
108 ioctl_fd = 3,
109 netlink_fd = 4,
110};
111
112struct globals {
113 smallint iface_last_status;
114 smallint iface_prev_status;
115 smallint iface_exists;
116 smallint api_method_num;
117
118 /* Used in getopt32, must have sizeof == sizeof(int) */
119 unsigned poll_time;
120 unsigned delay_up;
121 unsigned delay_down;
122
123 const char *iface;
124 const char *api_mode;
125 const char *script_name;
126 const char *extra_arg;
127};
128#define G (*ptr_to_globals)
129#define INIT_G() do { \
130 SET_PTR_TO_GLOBALS(xzalloc(sizeof(G))); \
131 G.iface_last_status = -1; \
132 G.iface_exists = 1; \
133 G.poll_time = 1; \
134 G.delay_down = 5; \
135 G.iface = "eth0"; \
136 G.api_mode = "a"; \
137 G.script_name = "/etc/ifplugd/ifplugd.action"; \
138} while (0)
139
140
141/* Utility routines */
142
143static void set_ifreq_to_ifname(struct ifreq *ifreq)
144{
145 memset(ifreq, 0, sizeof(struct ifreq));
146 strncpy_IFNAMSIZ(ifreq->ifr_name, G.iface);
147}
148
149static int network_ioctl(int request, void* data, const char *errmsg)
150{
151 int r = ioctl(ioctl_fd, request, data);
152 if (r < 0 && errmsg)
153 bb_perror_msg("%s failed", errmsg);
154 return r;
155}
156
157/* Link detection routines and table */
158
159static smallint detect_link_mii(void)
160{
161 /* char buffer instead of bona-fide struct avoids aliasing warning */
162 char buf[sizeof(struct ifreq)];
163 struct ifreq *const ifreq = (void *)buf;
164
165 struct mii_ioctl_data *mii = (void *)&ifreq->ifr_data;
166
167 set_ifreq_to_ifname(ifreq);
168
169 if (network_ioctl(SIOCGMIIPHY, ifreq, "SIOCGMIIPHY") < 0) {
170 return IFSTATUS_ERR;
171 }
172
173 mii->reg_num = 1;
174
175 if (network_ioctl(SIOCGMIIREG, ifreq, "SIOCGMIIREG") < 0) {
176 return IFSTATUS_ERR;
177 }
178
179 return (mii->val_out & 0x0004) ? IFSTATUS_UP : IFSTATUS_DOWN;
180}
181
182static smallint detect_link_priv(void)
183{
184 /* char buffer instead of bona-fide struct avoids aliasing warning */
185 char buf[sizeof(struct ifreq)];
186 struct ifreq *const ifreq = (void *)buf;
187
188 struct mii_ioctl_data *mii = (void *)&ifreq->ifr_data;
189
190 set_ifreq_to_ifname(ifreq);
191
192 if (network_ioctl(SIOCDEVPRIVATE, ifreq, "SIOCDEVPRIVATE") < 0) {
193 return IFSTATUS_ERR;
194 }
195
196 mii->reg_num = 1;
197
198 if (network_ioctl(SIOCDEVPRIVATE+1, ifreq, "SIOCDEVPRIVATE+1") < 0) {
199 return IFSTATUS_ERR;
200 }
201
202 return (mii->val_out & 0x0004) ? IFSTATUS_UP : IFSTATUS_DOWN;
203}
204
205static smallint detect_link_ethtool(void)
206{
207 struct ifreq ifreq;
208 struct ethtool_value edata;
209
210 set_ifreq_to_ifname(&ifreq);
211
212 edata.cmd = ETHTOOL_GLINK;
213 ifreq.ifr_data = (void*) &edata;
214
215 if (network_ioctl(SIOCETHTOOL, &ifreq, "ETHTOOL_GLINK") < 0) {
216 return IFSTATUS_ERR;
217 }
218
219 return edata.data ? IFSTATUS_UP : IFSTATUS_DOWN;
220}
221
222static smallint detect_link_iff(void)
223{
224 struct ifreq ifreq;
225
226 set_ifreq_to_ifname(&ifreq);
227
228 if (network_ioctl(SIOCGIFFLAGS, &ifreq, "SIOCGIFFLAGS") < 0) {
229 return IFSTATUS_ERR;
230 }
231
232 /* If IFF_UP is not set (interface is down), IFF_RUNNING is never set
233 * regardless of link status. Simply continue to report last status -
234 * no point in reporting spurious link downs if interface is disabled
235 * by admin. When/if it will be brought up,
236 * we'll report real link status.
237 */
238 if (!(ifreq.ifr_flags & IFF_UP) && G.iface_last_status != IFSTATUS_ERR)
239 return G.iface_last_status;
240
241 return (ifreq.ifr_flags & IFF_RUNNING) ? IFSTATUS_UP : IFSTATUS_DOWN;
242}
243
244static smallint detect_link_wlan(void)
245{
246 int i;
247 struct iwreq iwrequest;
248 uint8_t mac[ETH_ALEN];
249
250 memset(&iwrequest, 0, sizeof(iwrequest));
251 strncpy_IFNAMSIZ(iwrequest.ifr_ifrn.ifrn_name, G.iface);
252
253 if (network_ioctl(SIOCGIWAP, &iwrequest, "SIOCGIWAP") < 0) {
254 return IFSTATUS_ERR;
255 }
256
257 memcpy(mac, &iwrequest.u.ap_addr.sa_data, ETH_ALEN);
258
259 if (mac[0] == 0xFF || mac[0] == 0x44 || mac[0] == 0x00) {
260 for (i = 1; i < ETH_ALEN; ++i) {
261 if (mac[i] != mac[0])
262 return IFSTATUS_UP;
263 }
264 return IFSTATUS_DOWN;
265 }
266
267 return IFSTATUS_UP;
268}
269
270enum { // api mode
271 API_ETHTOOL, // 'e'
272 API_MII, // 'm'
273 API_PRIVATE, // 'p'
274 API_WLAN, // 'w'
275 API_IFF, // 'i'
276 API_AUTO, // 'a'
277};
278
279static const char api_modes[] ALIGN1 = "empwia";
280
281static const struct {
282 const char *name;
283 smallint (*func)(void);
284} method_table[] = {
285 { "SIOCETHTOOL" , &detect_link_ethtool },
286 { "SIOCGMIIPHY" , &detect_link_mii },
287 { "SIOCDEVPRIVATE" , &detect_link_priv },
288 { "wireless extension", &detect_link_wlan },
289 { "IFF_RUNNING" , &detect_link_iff },
290};
291
292
293
294static const char *strstatus(int status)
295{
296 if (status == IFSTATUS_ERR)
297 return "error";
298 return "down\0up" + (status * 5);
299}
300
301static int run_script(const char *action)
302{
303 char *env_PREVIOUS, *env_CURRENT;
304 char *argv[5];
305 int r;
306
307 bb_error_msg("executing '%s %s %s'", G.script_name, G.iface, action);
308
309 argv[0] = (char*) G.script_name;
310 argv[1] = (char*) G.iface;
311 argv[2] = (char*) action;
312 argv[3] = (char*) G.extra_arg;
313 argv[4] = NULL;
314
315 env_PREVIOUS = xasprintf("%s=%s", IFPLUGD_ENV_PREVIOUS, strstatus(G.iface_prev_status));
316 putenv(env_PREVIOUS);
317 env_CURRENT = xasprintf("%s=%s", IFPLUGD_ENV_CURRENT, strstatus(G.iface_last_status));
318 putenv(env_CURRENT);
319
320 /* r < 0 - can't exec, 0 <= r < 0x180 - exited, >=0x180 - killed by sig (r-0x180) */
321 r = spawn_and_wait(argv);
322
323 unsetenv(IFPLUGD_ENV_PREVIOUS);
324 unsetenv(IFPLUGD_ENV_CURRENT);
325 free(env_PREVIOUS);
326 free(env_CURRENT);
327
328 bb_error_msg("exit code: %d", r & 0xff);
329 return (option_mask32 & FLAG_IGNORE_RETVAL) ? 0 : r;
330}
331
332static void up_iface(void)
333{
334 struct ifreq ifrequest;
335
336 if (!G.iface_exists)
337 return;
338
339 set_ifreq_to_ifname(&ifrequest);
340 if (network_ioctl(SIOCGIFFLAGS, &ifrequest, "getting interface flags") < 0) {
341 G.iface_exists = 0;
342 return;
343 }
344
345 if (!(ifrequest.ifr_flags & IFF_UP)) {
346 ifrequest.ifr_flags |= IFF_UP;
347 /* Let user know we mess up with interface */
348 bb_error_msg("upping interface");
349 if (network_ioctl(SIOCSIFFLAGS, &ifrequest, "setting interface flags") < 0)
350 xfunc_die();
351 }
352
353#if 0 /* why do we mess with IP addr? It's not our business */
354 if (network_ioctl(SIOCGIFADDR, &ifrequest, "can't get interface address") < 0) {
355 } else if (ifrequest.ifr_addr.sa_family != AF_INET) {
356 bb_perror_msg("the interface is not IP-based");
357 } else {
358 ((struct sockaddr_in*)(&ifrequest.ifr_addr))->sin_addr.s_addr = INADDR_ANY;
359 network_ioctl(SIOCSIFADDR, &ifrequest, "can't set interface address");
360 }
361 network_ioctl(SIOCGIFFLAGS, &ifrequest, "can't get interface flags");
362#endif
363}
364
365static void maybe_up_new_iface(void)
366{
367 if (!(option_mask32 & FLAG_NO_AUTO))
368 up_iface();
369
370#if 0 /* bloat */
371 struct ifreq ifrequest;
372 struct ethtool_drvinfo driver_info;
373
374 set_ifreq_to_ifname(&ifrequest);
375 driver_info.cmd = ETHTOOL_GDRVINFO;
376 ifrequest.ifr_data = &driver_info;
377 if (network_ioctl(SIOCETHTOOL, &ifrequest, NULL) == 0) {
378 char buf[sizeof("/xx:xx:xx:xx:xx:xx")];
379
380 /* Get MAC */
381 buf[0] = '\0';
382 set_ifreq_to_ifname(&ifrequest);
383 if (network_ioctl(SIOCGIFHWADDR, &ifrequest, NULL) == 0) {
384 sprintf(buf, "/%02X:%02X:%02X:%02X:%02X:%02X",
385 (uint8_t)(ifrequest.ifr_hwaddr.sa_data[0]),
386 (uint8_t)(ifrequest.ifr_hwaddr.sa_data[1]),
387 (uint8_t)(ifrequest.ifr_hwaddr.sa_data[2]),
388 (uint8_t)(ifrequest.ifr_hwaddr.sa_data[3]),
389 (uint8_t)(ifrequest.ifr_hwaddr.sa_data[4]),
390 (uint8_t)(ifrequest.ifr_hwaddr.sa_data[5]));
391 }
392
393 bb_error_msg("using interface %s%s with driver<%s> (version: %s)",
394 G.iface, buf, driver_info.driver, driver_info.version);
395 }
396#endif
397 if (G.api_mode[0] == 'a')
398 G.api_method_num = API_AUTO;
399}
400
401static smallint detect_link(void)
402{
403 smallint status;
404
405 if (!G.iface_exists)
406 return (option_mask32 & FLAG_MONITOR) ? IFSTATUS_DOWN : IFSTATUS_ERR;
407
408 /* Some drivers can't detect link status when the interface is down.
409 * I imagine detect_link_iff() is the most vulnerable.
410 * That's why -a "noauto" in an option, not a hardwired behavior.
411 */
412 if (!(option_mask32 & FLAG_NO_AUTO))
413 up_iface();
414
415 if (G.api_method_num == API_AUTO) {
416 int i;
417 smallint sv_logmode;
418
419 sv_logmode = logmode;
420 for (i = 0; i < ARRAY_SIZE(method_table); i++) {
421 logmode = LOGMODE_NONE;
422 status = method_table[i].func();
423 logmode = sv_logmode;
424 if (status != IFSTATUS_ERR) {
425 G.api_method_num = i;
426 bb_error_msg("using %s detection mode", method_table[i].name);
427 break;
428 }
429 }
430 } else {
431 status = method_table[G.api_method_num].func();
432 }
433
434 if (status == IFSTATUS_ERR) {
435 if (option_mask32 & FLAG_IGNORE_FAIL)
436 status = IFSTATUS_DOWN;
437 else if (option_mask32 & FLAG_IGNORE_FAIL_POSITIVE)
438 status = IFSTATUS_UP;
439 else if (G.api_mode[0] == 'a')
440 bb_error_msg("can't detect link status");
441 }
442
443 if (status != G.iface_last_status) {
444 G.iface_prev_status = G.iface_last_status;
445 G.iface_last_status = status;
446 }
447
448 return status;
449}
450
451static NOINLINE int check_existence_through_netlink(void)
452{
453 int iface_len;
454 /* Buffer was 1K, but on linux-3.9.9 it was reported to be too small.
455 * netlink.h: "limit to 8K to avoid MSG_TRUNC when PAGE_SIZE is very large".
456 * Note: on error returns (-1) we exit, no need to free replybuf.
457 */
458 enum { BUF_SIZE = 8 * 1024 };
459 char *replybuf = xmalloc(BUF_SIZE);
460
461 iface_len = strlen(G.iface);
462 while (1) {
463 struct nlmsghdr *mhdr;
464 ssize_t bytes;
465
466 bytes = recv(netlink_fd, replybuf, BUF_SIZE, MSG_DONTWAIT);
467 if (bytes < 0) {
468 if (errno == EAGAIN)
469 goto ret;
470 if (errno == EINTR)
471 continue;
472 bb_perror_msg("netlink: recv");
473 return -1;
474 }
475
476 mhdr = (struct nlmsghdr*)replybuf;
477 while (bytes > 0) {
478 if (!NLMSG_OK(mhdr, bytes)) {
479 bb_error_msg("netlink packet too small or truncated");
480 return -1;
481 }
482
483 if (mhdr->nlmsg_type == RTM_NEWLINK || mhdr->nlmsg_type == RTM_DELLINK) {
484 struct rtattr *attr;
485 int attr_len;
486
487 if (mhdr->nlmsg_len < NLMSG_LENGTH(sizeof(struct ifinfomsg))) {
488 bb_error_msg("netlink packet too small or truncated");
489 return -1;
490 }
491
492 attr = IFLA_RTA(NLMSG_DATA(mhdr));
493 attr_len = IFLA_PAYLOAD(mhdr);
494
495 while (RTA_OK(attr, attr_len)) {
496 if (attr->rta_type == IFLA_IFNAME) {
497 int len = RTA_PAYLOAD(attr);
498 if (len > IFNAMSIZ)
499 len = IFNAMSIZ;
500 if (iface_len <= len
501 && strncmp(G.iface, RTA_DATA(attr), len) == 0
502 ) {
503 G.iface_exists = (mhdr->nlmsg_type == RTM_NEWLINK);
504 }
505 }
506 attr = RTA_NEXT(attr, attr_len);
507 }
508 }
509
510 mhdr = NLMSG_NEXT(mhdr, bytes);
511 }
512 }
513
514 ret:
515 free(replybuf);
516 return G.iface_exists;
517}
518
519#if ENABLE_FEATURE_PIDFILE
520static NOINLINE pid_t read_pid(const char *filename)
521{
522 int len;
523 char buf[128];
524
525 len = open_read_close(filename, buf, 127);
526 if (len > 0) {
527 buf[len] = '\0';
528 /* returns ULONG_MAX on error => -1 */
529 return bb_strtoul(buf, NULL, 10);
530 }
531 return 0;
532}
533#endif
534
535int ifplugd_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
536int ifplugd_main(int argc UNUSED_PARAM, char **argv)
537{
538 int iface_status;
539 int delay_time;
540 const char *iface_status_str;
541 struct pollfd netlink_pollfd[1];
542 unsigned opts;
543 const char *api_mode_found;
544#if ENABLE_FEATURE_PIDFILE
545 char *pidfile_name;
546 pid_t pid_from_pidfile;
547#endif
548
549 INIT_G();
550
551 opt_complementary = "t+:u+:d+";
552 opts = getopt32(argv, OPTION_STR,
553 &G.iface, &G.script_name, &G.poll_time, &G.delay_up,
554 &G.delay_down, &G.api_mode, &G.extra_arg);
555 G.poll_time *= 1000;
556
557 applet_name = xasprintf("ifplugd(%s)", G.iface);
558
559#if ENABLE_FEATURE_PIDFILE
560 pidfile_name = xasprintf(CONFIG_PID_FILE_PATH "/ifplugd.%s.pid", G.iface);
561 pid_from_pidfile = read_pid(pidfile_name);
562
563 if (opts & FLAG_KILL) {
564 if (pid_from_pidfile > 0)
565 /* Upstream tool use SIGINT for -k */
566 kill(pid_from_pidfile, SIGINT);
567 return EXIT_SUCCESS;
568 }
569
570 if (pid_from_pidfile > 0 && kill(pid_from_pidfile, 0) == 0)
571 bb_error_msg_and_die("daemon already running");
572#endif
573
574 api_mode_found = strchr(api_modes, G.api_mode[0]);
575 if (!api_mode_found)
576 bb_error_msg_and_die("unknown API mode '%s'", G.api_mode);
577 G.api_method_num = api_mode_found - api_modes;
578
579 if (!(opts & FLAG_NO_DAEMON))
580 bb_daemonize_or_rexec(DAEMON_CHDIR_ROOT, argv);
581
582 xmove_fd(xsocket(AF_INET, SOCK_DGRAM, 0), ioctl_fd);
583 if (opts & FLAG_MONITOR) {
584 struct sockaddr_nl addr;
585 int fd = xsocket(PF_NETLINK, SOCK_DGRAM, NETLINK_ROUTE);
586
587 memset(&addr, 0, sizeof(addr));
588 addr.nl_family = AF_NETLINK;
589 addr.nl_groups = RTMGRP_LINK;
590 addr.nl_pid = getpid();
591
592 xbind(fd, (struct sockaddr*)&addr, sizeof(addr));
593 xmove_fd(fd, netlink_fd);
594 }
595
596 write_pidfile(pidfile_name);
597
598 /* this can't be moved before socket creation */
599 if (!(opts & FLAG_NO_SYSLOG)) {
600 openlog(applet_name, 0, LOG_DAEMON);
601 logmode |= LOGMODE_SYSLOG;
602 }
603
604 bb_signals(0
605 | (1 << SIGINT )
606 | (1 << SIGTERM)
607 | (1 << SIGQUIT)
608 | (1 << SIGHUP ) /* why we ignore it? */
609 /* | (1 << SIGCHLD) - run_script does not use it anymore */
610 , record_signo);
611
612 bb_error_msg("started: %s", bb_banner);
613
614 if (opts & FLAG_MONITOR) {
615 struct ifreq ifrequest;
616 set_ifreq_to_ifname(&ifrequest);
617 G.iface_exists = (network_ioctl(SIOCGIFINDEX, &ifrequest, NULL) == 0);
618 }
619
620 if (G.iface_exists)
621 maybe_up_new_iface();
622
623 iface_status = detect_link();
624 if (iface_status == IFSTATUS_ERR)
625 goto exiting;
626 iface_status_str = strstatus(iface_status);
627
628 if (opts & FLAG_MONITOR) {
629 bb_error_msg("interface %s",
630 G.iface_exists ? "exists"
631 : "doesn't exist, waiting");
632 }
633 /* else we assume it always exists, but don't mislead user
634 * by potentially lying that it really exists */
635
636 if (G.iface_exists) {
637 bb_error_msg("link is %s", iface_status_str);
638 }
639
640 if ((!(opts & FLAG_NO_STARTUP)
641 && iface_status == IFSTATUS_UP
642 )
643 || (opts & FLAG_INITIAL_DOWN)
644 ) {
645 if (run_script(iface_status_str) != 0)
646 goto exiting;
647 }
648
649 /* Main loop */
650 netlink_pollfd[0].fd = netlink_fd;
651 netlink_pollfd[0].events = POLLIN;
652 delay_time = 0;
653 while (1) {
654 int iface_status_old;
655 int iface_exists_old;
656
657 switch (bb_got_signal) {
658 case SIGINT:
659 case SIGTERM:
660 bb_got_signal = 0;
661 goto cleanup;
662 case SIGQUIT:
663 bb_got_signal = 0;
664 goto exiting;
665 default:
666 bb_got_signal = 0;
667 break;
668 }
669
670 if (poll(netlink_pollfd,
671 (opts & FLAG_MONITOR) ? 1 : 0,
672 G.poll_time
673 ) < 0
674 ) {
675 if (errno == EINTR)
676 continue;
677 bb_perror_msg("poll");
678 goto exiting;
679 }
680
681 iface_status_old = iface_status;
682 iface_exists_old = G.iface_exists;
683
684 if ((opts & FLAG_MONITOR)
685 && (netlink_pollfd[0].revents & POLLIN)
686 ) {
687 G.iface_exists = check_existence_through_netlink();
688 if (G.iface_exists < 0) /* error */
689 goto exiting;
690 if (iface_exists_old != G.iface_exists) {
691 bb_error_msg("interface %sappeared",
692 G.iface_exists ? "" : "dis");
693 if (G.iface_exists)
694 maybe_up_new_iface();
695 }
696 }
697
698 /* note: if !G.iface_exists, returns DOWN */
699 iface_status = detect_link();
700 if (iface_status == IFSTATUS_ERR) {
701 if (!(opts & FLAG_MONITOR))
702 goto exiting;
703 iface_status = IFSTATUS_DOWN;
704 }
705 iface_status_str = strstatus(iface_status);
706
707 if (iface_status_old != iface_status) {
708 bb_error_msg("link is %s", iface_status_str);
709
710 if (delay_time) {
711 /* link restored its old status before
712 * we run script. don't run the script: */
713 delay_time = 0;
714 } else {
715 delay_time = monotonic_sec();
716 if (iface_status == IFSTATUS_UP)
717 delay_time += G.delay_up;
718 if (iface_status == IFSTATUS_DOWN)
719 delay_time += G.delay_down;
720 if (delay_time == 0)
721 delay_time++;
722 }
723 }
724
725 if (delay_time && (int)(monotonic_sec() - delay_time) >= 0) {
726 delay_time = 0;
727 if (run_script(iface_status_str) != 0)
728 goto exiting;
729 }
730 } /* while (1) */
731
732 cleanup:
733 if (!(opts & FLAG_NO_SHUTDOWN)
734 && (iface_status == IFSTATUS_UP
735 || (iface_status == IFSTATUS_DOWN && delay_time)
736 )
737 ) {
738 setenv(IFPLUGD_ENV_PREVIOUS, strstatus(iface_status), 1);
739 setenv(IFPLUGD_ENV_CURRENT, strstatus(-1), 1);
740 run_script("down\0up"); /* reusing string */
741 }
742
743 exiting:
744 remove_pidfile(pidfile_name);
745 bb_error_msg_and_die("exiting");
746}
747
generated by cgit at 2024-05-15 08:38:47 (GMT)