xref: /freebsd/sbin/devd/devd.cc (revision a35f04fba2ebb8f86d4cbdc710c89a094572b08e)
1 /*-
2  * Copyright (c) 2002-2010 M. Warner Losh.
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  *
26  * my_system is a variation on lib/libc/stdlib/system.c:
27  *
28  * Copyright (c) 1988, 1993
29  *	The Regents of the University of California.  All rights reserved.
30  *
31  * Redistribution and use in source and binary forms, with or without
32  * modification, are permitted provided that the following conditions
33  * are met:
34  * 1. Redistributions of source code must retain the above copyright
35  *    notice, this list of conditions and the following disclaimer.
36  * 2. Redistributions in binary form must reproduce the above copyright
37  *    notice, this list of conditions and the following disclaimer in the
38  *    documentation and/or other materials provided with the distribution.
39  * 3. Neither the name of the University nor the names of its contributors
40  *    may be used to endorse or promote products derived from this software
41  *    without specific prior written permission.
42  *
43  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
44  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
45  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
46  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
47  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
48  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
49  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
50  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
51  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
52  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
53  * SUCH DAMAGE.
54  */
55 
56 /*
57  * DEVD control daemon.
58  */
59 
60 // TODO list:
61 //	o devd.conf and devd man pages need a lot of help:
62 //	  - devd needs to document the unix domain socket
63 //	  - devd.conf needs more details on the supported statements.
64 
65 #include <sys/cdefs.h>
66 __FBSDID("$FreeBSD$");
67 
68 #include <sys/param.h>
69 #include <sys/socket.h>
70 #include <sys/stat.h>
71 #include <sys/sysctl.h>
72 #include <sys/types.h>
73 #include <sys/wait.h>
74 #include <sys/un.h>
75 
76 #include <cctype>
77 #include <cerrno>
78 #include <cstdlib>
79 #include <cstdio>
80 #include <csignal>
81 #include <cstring>
82 #include <cstdarg>
83 
84 #include <dirent.h>
85 #include <err.h>
86 #include <fcntl.h>
87 #include <libutil.h>
88 #include <paths.h>
89 #include <poll.h>
90 #include <regex.h>
91 #include <syslog.h>
92 #include <unistd.h>
93 
94 #include <algorithm>
95 #include <map>
96 #include <string>
97 #include <list>
98 #include <stdexcept>
99 #include <vector>
100 
101 #include "devd.h"		/* C compatible definitions */
102 #include "devd.hh"		/* C++ class definitions */
103 
104 #define STREAMPIPE "/var/run/devd.pipe"
105 #define SEQPACKETPIPE "/var/run/devd.seqpacket.pipe"
106 #define CF "/etc/devd.conf"
107 #define SYSCTL "hw.bus.devctl_queue"
108 
109 /*
110  * Since the client socket is nonblocking, we must increase its send buffer to
111  * handle brief event storms.  On FreeBSD, AF_UNIX sockets don't have a receive
112  * buffer, so the client can't increase the buffersize by itself.
113  *
114  * For example, when creating a ZFS pool, devd emits one 165 character
115  * resource.fs.zfs.statechange message for each vdev in the pool.  The kernel
116  * allocates a 4608B mbuf for each message.  Modern technology places a limit of
117  * roughly 450 drives/rack, and it's unlikely that a zpool will ever be larger
118  * than that.
119  *
120  * 450 drives * 165 bytes / drive = 74250B of data in the sockbuf
121  * 450 drives * 4608B / drive = 2073600B of mbufs in the sockbuf
122  *
123  * We can't directly set the sockbuf's mbuf limit, but we can do it indirectly.
124  * The kernel sets it to the minimum of a hard-coded maximum value and sbcc *
125  * kern.ipc.sockbuf_waste_factor, where sbcc is the socket buffer size set by
126  * the user.  The default value of kern.ipc.sockbuf_waste_factor is 8.  If we
127  * set the bufsize to 256k and use the kern.ipc.sockbuf_waste_factor, then the
128  * kernel will set the mbuf limit to 2MB, which is just large enough for 450
129  * drives.  It also happens to be the same as the hardcoded maximum value.
130  */
131 #define CLIENT_BUFSIZE 262144
132 
133 using namespace std;
134 
135 typedef struct client {
136 	int fd;
137 	int socktype;
138 } client_t;
139 
140 extern FILE *yyin;
141 extern int lineno;
142 
143 static const char notify = '!';
144 static const char nomatch = '?';
145 static const char attach = '+';
146 static const char detach = '-';
147 
148 static struct pidfh *pfh;
149 
150 static int no_daemon = 0;
151 static int daemonize_quick = 0;
152 static int quiet_mode = 0;
153 static unsigned total_events = 0;
154 static volatile sig_atomic_t got_siginfo = 0;
155 static volatile sig_atomic_t romeo_must_die = 0;
156 
157 static const char *configfile = CF;
158 
159 static void devdlog(int priority, const char* message, ...)
160 	__printflike(2, 3);
161 static void event_loop(void);
162 static void usage(void);
163 
164 template <class T> void
165 delete_and_clear(vector<T *> &v)
166 {
167 	typename vector<T *>::const_iterator i;
168 
169 	for (i = v.begin(); i != v.end(); ++i)
170 		delete *i;
171 	v.clear();
172 }
173 
174 config cfg;
175 
176 event_proc::event_proc() : _prio(-1)
177 {
178 	_epsvec.reserve(4);
179 }
180 
181 event_proc::~event_proc()
182 {
183 	delete_and_clear(_epsvec);
184 }
185 
186 void
187 event_proc::add(eps *eps)
188 {
189 	_epsvec.push_back(eps);
190 }
191 
192 bool
193 event_proc::matches(config &c) const
194 {
195 	vector<eps *>::const_iterator i;
196 
197 	for (i = _epsvec.begin(); i != _epsvec.end(); ++i)
198 		if (!(*i)->do_match(c))
199 			return (false);
200 	return (true);
201 }
202 
203 bool
204 event_proc::run(config &c) const
205 {
206 	vector<eps *>::const_iterator i;
207 
208 	for (i = _epsvec.begin(); i != _epsvec.end(); ++i)
209 		if (!(*i)->do_action(c))
210 			return (false);
211 	return (true);
212 }
213 
214 action::action(const char *cmd)
215 	: _cmd(cmd)
216 {
217 	// nothing
218 }
219 
220 action::~action()
221 {
222 	// nothing
223 }
224 
225 static int
226 my_system(const char *command)
227 {
228 	pid_t pid, savedpid;
229 	int pstat;
230 	struct sigaction ign, intact, quitact;
231 	sigset_t newsigblock, oldsigblock;
232 
233 	if (!command)		/* just checking... */
234 		return (1);
235 
236 	/*
237 	 * Ignore SIGINT and SIGQUIT, block SIGCHLD. Remember to save
238 	 * existing signal dispositions.
239 	 */
240 	ign.sa_handler = SIG_IGN;
241 	::sigemptyset(&ign.sa_mask);
242 	ign.sa_flags = 0;
243 	::sigaction(SIGINT, &ign, &intact);
244 	::sigaction(SIGQUIT, &ign, &quitact);
245 	::sigemptyset(&newsigblock);
246 	::sigaddset(&newsigblock, SIGCHLD);
247 	::sigprocmask(SIG_BLOCK, &newsigblock, &oldsigblock);
248 	switch (pid = ::fork()) {
249 	case -1:			/* error */
250 		break;
251 	case 0:				/* child */
252 		/*
253 		 * Restore original signal dispositions and exec the command.
254 		 */
255 		::sigaction(SIGINT, &intact, NULL);
256 		::sigaction(SIGQUIT,  &quitact, NULL);
257 		::sigprocmask(SIG_SETMASK, &oldsigblock, NULL);
258 		/*
259 		 * Close the PID file, and all other open descriptors.
260 		 * Inherit std{in,out,err} only.
261 		 */
262 		cfg.close_pidfile();
263 		::closefrom(3);
264 		::execl(_PATH_BSHELL, "sh", "-c", command, (char *)NULL);
265 		::_exit(127);
266 	default:			/* parent */
267 		savedpid = pid;
268 		do {
269 			pid = ::wait4(savedpid, &pstat, 0, (struct rusage *)0);
270 		} while (pid == -1 && errno == EINTR);
271 		break;
272 	}
273 	::sigaction(SIGINT, &intact, NULL);
274 	::sigaction(SIGQUIT,  &quitact, NULL);
275 	::sigprocmask(SIG_SETMASK, &oldsigblock, NULL);
276 	return (pid == -1 ? -1 : pstat);
277 }
278 
279 bool
280 action::do_action(config &c)
281 {
282 	string s = c.expand_string(_cmd.c_str());
283 	devdlog(LOG_INFO, "Executing '%s'\n", s.c_str());
284 	my_system(s.c_str());
285 	return (true);
286 }
287 
288 match::match(config &c, const char *var, const char *re) :
289 	_inv(re[0] == '!'),
290 	_var(var),
291 	_re(c.expand_string(_inv ? re + 1 : re, "^", "$"))
292 {
293 	regcomp(&_regex, _re.c_str(), REG_EXTENDED | REG_NOSUB | REG_ICASE);
294 }
295 
296 match::~match()
297 {
298 	regfree(&_regex);
299 }
300 
301 bool
302 match::do_match(config &c)
303 {
304 	const string &value = c.get_variable(_var);
305 	bool retval;
306 
307 	/*
308 	 * This function gets called WAY too often to justify calling syslog()
309 	 * each time, even at LOG_DEBUG.  Because if syslogd isn't running, it
310 	 * can consume excessive amounts of systime inside of connect().  Only
311 	 * log when we're in -d mode.
312 	 */
313 	if (no_daemon) {
314 		devdlog(LOG_DEBUG, "Testing %s=%s against %s, invert=%d\n",
315 		    _var.c_str(), value.c_str(), _re.c_str(), _inv);
316 	}
317 
318 	retval = (regexec(&_regex, value.c_str(), 0, NULL, 0) == 0);
319 	if (_inv == 1)
320 		retval = (retval == 0) ? 1 : 0;
321 
322 	return (retval);
323 }
324 
325 #include <sys/sockio.h>
326 #include <net/if.h>
327 #include <net/if_media.h>
328 
329 media::media(config &, const char *var, const char *type)
330 	: _var(var), _type(-1)
331 {
332 	static struct ifmedia_description media_types[] = {
333 		{ IFM_ETHER,		"Ethernet" },
334 		{ IFM_TOKEN,		"Tokenring" },
335 		{ IFM_FDDI,		"FDDI" },
336 		{ IFM_IEEE80211,	"802.11" },
337 		{ IFM_ATM,		"ATM" },
338 		{ -1,			"unknown" },
339 		{ 0, NULL },
340 	};
341 	for (int i = 0; media_types[i].ifmt_string != NULL; ++i)
342 		if (strcasecmp(type, media_types[i].ifmt_string) == 0) {
343 			_type = media_types[i].ifmt_word;
344 			break;
345 		}
346 }
347 
348 media::~media()
349 {
350 }
351 
352 bool
353 media::do_match(config &c)
354 {
355 	string value;
356 	struct ifmediareq ifmr;
357 	bool retval;
358 	int s;
359 
360 	// Since we can be called from both a device attach/detach
361 	// context where device-name is defined and what we want,
362 	// as well as from a link status context, where subsystem is
363 	// the name of interest, first try device-name and fall back
364 	// to subsystem if none exists.
365 	value = c.get_variable("device-name");
366 	if (value.empty())
367 		value = c.get_variable("subsystem");
368 	devdlog(LOG_DEBUG, "Testing media type of %s against 0x%x\n",
369 		    value.c_str(), _type);
370 
371 	retval = false;
372 
373 	s = socket(PF_INET, SOCK_DGRAM, 0);
374 	if (s >= 0) {
375 		memset(&ifmr, 0, sizeof(ifmr));
376 		strlcpy(ifmr.ifm_name, value.c_str(), sizeof(ifmr.ifm_name));
377 
378 		if (ioctl(s, SIOCGIFMEDIA, (caddr_t)&ifmr) >= 0 &&
379 		    ifmr.ifm_status & IFM_AVALID) {
380 			devdlog(LOG_DEBUG, "%s has media type 0x%x\n",
381 				    value.c_str(), IFM_TYPE(ifmr.ifm_active));
382 			retval = (IFM_TYPE(ifmr.ifm_active) == _type);
383 		} else if (_type == -1) {
384 			devdlog(LOG_DEBUG, "%s has unknown media type\n",
385 				    value.c_str());
386 			retval = true;
387 		}
388 		close(s);
389 	}
390 
391 	return (retval);
392 }
393 
394 const string var_list::bogus = "_$_$_$_$_B_O_G_U_S_$_$_$_$_";
395 const string var_list::nothing = "";
396 
397 const string &
398 var_list::get_variable(const string &var) const
399 {
400 	map<string, string>::const_iterator i;
401 
402 	i = _vars.find(var);
403 	if (i == _vars.end())
404 		return (var_list::bogus);
405 	return (i->second);
406 }
407 
408 bool
409 var_list::is_set(const string &var) const
410 {
411 	return (_vars.find(var) != _vars.end());
412 }
413 
414 void
415 var_list::set_variable(const string &var, const string &val)
416 {
417 	/*
418 	 * This function gets called WAY too often to justify calling syslog()
419 	 * each time, even at LOG_DEBUG.  Because if syslogd isn't running, it
420 	 * can consume excessive amounts of systime inside of connect().  Only
421 	 * log when we're in -d mode.
422 	 */
423 	if (no_daemon)
424 		devdlog(LOG_DEBUG, "setting %s=%s\n", var.c_str(), val.c_str());
425 	_vars[var] = val;
426 }
427 
428 void
429 config::reset(void)
430 {
431 	_dir_list.clear();
432 	delete_and_clear(_var_list_table);
433 	delete_and_clear(_attach_list);
434 	delete_and_clear(_detach_list);
435 	delete_and_clear(_nomatch_list);
436 	delete_and_clear(_notify_list);
437 }
438 
439 void
440 config::parse_one_file(const char *fn)
441 {
442 	devdlog(LOG_DEBUG, "Parsing %s\n", fn);
443 	yyin = fopen(fn, "r");
444 	if (yyin == NULL)
445 		err(1, "Cannot open config file %s", fn);
446 	lineno = 1;
447 	if (yyparse() != 0)
448 		errx(1, "Cannot parse %s at line %d", fn, lineno);
449 	fclose(yyin);
450 }
451 
452 void
453 config::parse_files_in_dir(const char *dirname)
454 {
455 	DIR *dirp;
456 	struct dirent *dp;
457 	char path[PATH_MAX];
458 
459 	devdlog(LOG_DEBUG, "Parsing files in %s\n", dirname);
460 	dirp = opendir(dirname);
461 	if (dirp == NULL)
462 		return;
463 	readdir(dirp);		/* Skip . */
464 	readdir(dirp);		/* Skip .. */
465 	while ((dp = readdir(dirp)) != NULL) {
466 		if (strcmp(dp->d_name + dp->d_namlen - 5, ".conf") == 0) {
467 			snprintf(path, sizeof(path), "%s/%s",
468 			    dirname, dp->d_name);
469 			parse_one_file(path);
470 		}
471 	}
472 	closedir(dirp);
473 }
474 
475 class epv_greater {
476 public:
477 	int operator()(event_proc *const&l1, event_proc *const&l2) const
478 	{
479 		return (l1->get_priority() > l2->get_priority());
480 	}
481 };
482 
483 void
484 config::sort_vector(vector<event_proc *> &v)
485 {
486 	stable_sort(v.begin(), v.end(), epv_greater());
487 }
488 
489 void
490 config::parse(void)
491 {
492 	vector<string>::const_iterator i;
493 
494 	parse_one_file(configfile);
495 	for (i = _dir_list.begin(); i != _dir_list.end(); ++i)
496 		parse_files_in_dir((*i).c_str());
497 	sort_vector(_attach_list);
498 	sort_vector(_detach_list);
499 	sort_vector(_nomatch_list);
500 	sort_vector(_notify_list);
501 }
502 
503 void
504 config::open_pidfile()
505 {
506 	pid_t otherpid;
507 
508 	if (_pidfile.empty())
509 		return;
510 	pfh = pidfile_open(_pidfile.c_str(), 0600, &otherpid);
511 	if (pfh == NULL) {
512 		if (errno == EEXIST)
513 			errx(1, "devd already running, pid: %d", (int)otherpid);
514 		warn("cannot open pid file");
515 	}
516 }
517 
518 void
519 config::write_pidfile()
520 {
521 
522 	pidfile_write(pfh);
523 }
524 
525 void
526 config::close_pidfile()
527 {
528 
529 	pidfile_close(pfh);
530 }
531 
532 void
533 config::remove_pidfile()
534 {
535 
536 	pidfile_remove(pfh);
537 }
538 
539 void
540 config::add_attach(int prio, event_proc *p)
541 {
542 	p->set_priority(prio);
543 	_attach_list.push_back(p);
544 }
545 
546 void
547 config::add_detach(int prio, event_proc *p)
548 {
549 	p->set_priority(prio);
550 	_detach_list.push_back(p);
551 }
552 
553 void
554 config::add_directory(const char *dir)
555 {
556 	_dir_list.push_back(string(dir));
557 }
558 
559 void
560 config::add_nomatch(int prio, event_proc *p)
561 {
562 	p->set_priority(prio);
563 	_nomatch_list.push_back(p);
564 }
565 
566 void
567 config::add_notify(int prio, event_proc *p)
568 {
569 	p->set_priority(prio);
570 	_notify_list.push_back(p);
571 }
572 
573 void
574 config::set_pidfile(const char *fn)
575 {
576 	_pidfile = fn;
577 }
578 
579 void
580 config::push_var_table()
581 {
582 	var_list *vl;
583 
584 	vl = new var_list();
585 	_var_list_table.push_back(vl);
586 	devdlog(LOG_DEBUG, "Pushing table\n");
587 }
588 
589 void
590 config::pop_var_table()
591 {
592 	delete _var_list_table.back();
593 	_var_list_table.pop_back();
594 	devdlog(LOG_DEBUG, "Popping table\n");
595 }
596 
597 void
598 config::set_variable(const char *var, const char *val)
599 {
600 	_var_list_table.back()->set_variable(var, val);
601 }
602 
603 const string &
604 config::get_variable(const string &var)
605 {
606 	vector<var_list *>::reverse_iterator i;
607 
608 	for (i = _var_list_table.rbegin(); i != _var_list_table.rend(); ++i) {
609 		if ((*i)->is_set(var))
610 			return ((*i)->get_variable(var));
611 	}
612 	return (var_list::nothing);
613 }
614 
615 bool
616 config::is_id_char(char ch) const
617 {
618 	return (ch != '\0' && (isalpha(ch) || isdigit(ch) || ch == '_' ||
619 	    ch == '-'));
620 }
621 
622 void
623 config::expand_one(const char *&src, string &dst)
624 {
625 	int count;
626 	string buffer;
627 
628 	src++;
629 	// $$ -> $
630 	if (*src == '$') {
631 		dst += *src++;
632 		return;
633 	}
634 
635 	// $(foo) -> $(foo)
636 	// Not sure if I want to support this or not, so for now we just pass
637 	// it through.
638 	if (*src == '(') {
639 		dst += '$';
640 		count = 1;
641 		/* If the string ends before ) is matched , return. */
642 		while (count > 0 && *src) {
643 			if (*src == ')')
644 				count--;
645 			else if (*src == '(')
646 				count++;
647 			dst += *src++;
648 		}
649 		return;
650 	}
651 
652 	// $[^-A-Za-z_*] -> $\1
653 	if (!isalpha(*src) && *src != '_' && *src != '-' && *src != '*') {
654 		dst += '$';
655 		dst += *src++;
656 		return;
657 	}
658 
659 	// $var -> replace with value
660 	do {
661 		buffer += *src++;
662 	} while (is_id_char(*src));
663 	dst.append(get_variable(buffer));
664 }
665 
666 const string
667 config::expand_string(const char *src, const char *prepend, const char *append)
668 {
669 	const char *var_at;
670 	string dst;
671 
672 	/*
673 	 * 128 bytes is enough for 2427 of 2438 expansions that happen
674 	 * while parsing config files, as tested on 2013-01-30.
675 	 */
676 	dst.reserve(128);
677 
678 	if (prepend != NULL)
679 		dst = prepend;
680 
681 	for (;;) {
682 		var_at = strchr(src, '$');
683 		if (var_at == NULL) {
684 			dst.append(src);
685 			break;
686 		}
687 		dst.append(src, var_at - src);
688 		src = var_at;
689 		expand_one(src, dst);
690 	}
691 
692 	if (append != NULL)
693 		dst.append(append);
694 
695 	return (dst);
696 }
697 
698 bool
699 config::chop_var(char *&buffer, char *&lhs, char *&rhs) const
700 {
701 	char *walker;
702 
703 	if (*buffer == '\0')
704 		return (false);
705 	walker = lhs = buffer;
706 	while (is_id_char(*walker))
707 		walker++;
708 	if (*walker != '=')
709 		return (false);
710 	walker++;		// skip =
711 	if (*walker == '"') {
712 		walker++;	// skip "
713 		rhs = walker;
714 		while (*walker && *walker != '"')
715 			walker++;
716 		if (*walker != '"')
717 			return (false);
718 		rhs[-2] = '\0';
719 		*walker++ = '\0';
720 	} else {
721 		rhs = walker;
722 		while (*walker && !isspace(*walker))
723 			walker++;
724 		if (*walker != '\0')
725 			*walker++ = '\0';
726 		rhs[-1] = '\0';
727 	}
728 	while (isspace(*walker))
729 		walker++;
730 	buffer = walker;
731 	return (true);
732 }
733 
734 
735 char *
736 config::set_vars(char *buffer)
737 {
738 	char *lhs;
739 	char *rhs;
740 
741 	while (1) {
742 		if (!chop_var(buffer, lhs, rhs))
743 			break;
744 		set_variable(lhs, rhs);
745 	}
746 	return (buffer);
747 }
748 
749 void
750 config::find_and_execute(char type)
751 {
752 	vector<event_proc *> *l;
753 	vector<event_proc *>::const_iterator i;
754 	const char *s;
755 
756 	switch (type) {
757 	default:
758 		return;
759 	case notify:
760 		l = &_notify_list;
761 		s = "notify";
762 		break;
763 	case nomatch:
764 		l = &_nomatch_list;
765 		s = "nomatch";
766 		break;
767 	case attach:
768 		l = &_attach_list;
769 		s = "attach";
770 		break;
771 	case detach:
772 		l = &_detach_list;
773 		s = "detach";
774 		break;
775 	}
776 	devdlog(LOG_DEBUG, "Processing %s event\n", s);
777 	for (i = l->begin(); i != l->end(); ++i) {
778 		if ((*i)->matches(*this)) {
779 			(*i)->run(*this);
780 			break;
781 		}
782 	}
783 
784 }
785 
786 
787 static void
788 process_event(char *buffer)
789 {
790 	char type;
791 	char *sp;
792 	struct timeval tv;
793 	char *timestr;
794 
795 	sp = buffer + 1;
796 	devdlog(LOG_INFO, "Processing event '%s'\n", buffer);
797 	type = *buffer++;
798 	cfg.push_var_table();
799 	// $* is the entire line
800 	cfg.set_variable("*", buffer - 1);
801 	// $_ is the entire line without the initial character
802 	cfg.set_variable("_", buffer);
803 
804 	// Save the time this happened (as approximated by when we got
805 	// around to processing it).
806 	gettimeofday(&tv, NULL);
807 	asprintf(&timestr, "%jd.%06ld", (uintmax_t)tv.tv_sec, tv.tv_usec);
808 	cfg.set_variable("timestamp", timestr);
809 	free(timestr);
810 
811 	// Match doesn't have a device, and the format is a little
812 	// different, so handle it separately.
813 	switch (type) {
814 	case notify:
815 		//! (k=v)*
816 		sp = cfg.set_vars(sp);
817 		break;
818 	case nomatch:
819 		//? at location pnp-info on bus
820 		sp = strchr(sp, ' ');
821 		if (sp == NULL)
822 			return;	/* Can't happen? */
823 		*sp++ = '\0';
824 		while (isspace(*sp))
825 			sp++;
826 		if (strncmp(sp, "at ", 3) == 0)
827 			sp += 3;
828 		sp = cfg.set_vars(sp);
829 		while (isspace(*sp))
830 			sp++;
831 		if (strncmp(sp, "on ", 3) == 0)
832 			cfg.set_variable("bus", sp + 3);
833 		break;
834 	case attach:	/*FALLTHROUGH*/
835 	case detach:
836 		sp = strchr(sp, ' ');
837 		if (sp == NULL)
838 			return;	/* Can't happen? */
839 		*sp++ = '\0';
840 		cfg.set_variable("device-name", buffer);
841 		while (isspace(*sp))
842 			sp++;
843 		if (strncmp(sp, "at ", 3) == 0)
844 			sp += 3;
845 		sp = cfg.set_vars(sp);
846 		while (isspace(*sp))
847 			sp++;
848 		if (strncmp(sp, "on ", 3) == 0)
849 			cfg.set_variable("bus", sp + 3);
850 		break;
851 	}
852 
853 	cfg.find_and_execute(type);
854 	cfg.pop_var_table();
855 }
856 
857 int
858 create_socket(const char *name, int socktype)
859 {
860 	int fd, slen;
861 	struct sockaddr_un sun;
862 
863 	if ((fd = socket(PF_LOCAL, socktype, 0)) < 0)
864 		err(1, "socket");
865 	bzero(&sun, sizeof(sun));
866 	sun.sun_family = AF_UNIX;
867 	strlcpy(sun.sun_path, name, sizeof(sun.sun_path));
868 	slen = SUN_LEN(&sun);
869 	unlink(name);
870 	if (fcntl(fd, F_SETFL, O_NONBLOCK) < 0)
871 	    	err(1, "fcntl");
872 	if (::bind(fd, (struct sockaddr *) & sun, slen) < 0)
873 		err(1, "bind");
874 	listen(fd, 4);
875 	if (chown(name, 0, 0))	/* XXX - root.wheel */
876 		err(1, "chown");
877 	if (chmod(name, 0666))
878 		err(1, "chmod");
879 	return (fd);
880 }
881 
882 unsigned int max_clients = 10;	/* Default, can be overridden on cmdline. */
883 unsigned int num_clients;
884 
885 list<client_t> clients;
886 
887 void
888 notify_clients(const char *data, int len)
889 {
890 	list<client_t>::iterator i;
891 
892 	/*
893 	 * Deliver the data to all clients.  Throw clients overboard at the
894 	 * first sign of trouble.  This reaps clients who've died or closed
895 	 * their sockets, and also clients who are alive but failing to keep up
896 	 * (or who are maliciously not reading, to consume buffer space in
897 	 * kernel memory or tie up the limited number of available connections).
898 	 */
899 	for (i = clients.begin(); i != clients.end(); ) {
900 		int flags;
901 		if (i->socktype == SOCK_SEQPACKET)
902 			flags = MSG_EOR;
903 		else
904 			flags = 0;
905 
906 		if (send(i->fd, data, len, flags) != len) {
907 			--num_clients;
908 			close(i->fd);
909 			i = clients.erase(i);
910 			devdlog(LOG_WARNING, "notify_clients: send() failed; "
911 			    "dropping unresponsive client\n");
912 		} else
913 			++i;
914 	}
915 }
916 
917 void
918 check_clients(void)
919 {
920 	int s;
921 	struct pollfd pfd;
922 	list<client_t>::iterator i;
923 
924 	/*
925 	 * Check all existing clients to see if any of them have disappeared.
926 	 * Normally we reap clients when we get an error trying to send them an
927 	 * event.  This check eliminates the problem of an ever-growing list of
928 	 * zombie clients because we're never writing to them on a system
929 	 * without frequent device-change activity.
930 	 */
931 	pfd.events = 0;
932 	for (i = clients.begin(); i != clients.end(); ) {
933 		pfd.fd = i->fd;
934 		s = poll(&pfd, 1, 0);
935 		if ((s < 0 && s != EINTR ) ||
936 		    (s > 0 && (pfd.revents & POLLHUP))) {
937 			--num_clients;
938 			close(i->fd);
939 			i = clients.erase(i);
940 			devdlog(LOG_NOTICE, "check_clients:  "
941 			    "dropping disconnected client\n");
942 		} else
943 			++i;
944 	}
945 }
946 
947 void
948 new_client(int fd, int socktype)
949 {
950 	client_t s;
951 	int sndbuf_size;
952 
953 	/*
954 	 * First go reap any zombie clients, then accept the connection, and
955 	 * shut down the read side to stop clients from consuming kernel memory
956 	 * by sending large buffers full of data we'll never read.
957 	 */
958 	check_clients();
959 	s.socktype = socktype;
960 	s.fd = accept(fd, NULL, NULL);
961 	if (s.fd != -1) {
962 		sndbuf_size = CLIENT_BUFSIZE;
963 		if (setsockopt(s.fd, SOL_SOCKET, SO_SNDBUF, &sndbuf_size,
964 		    sizeof(sndbuf_size)))
965 			err(1, "setsockopt");
966 		shutdown(s.fd, SHUT_RD);
967 		clients.push_back(s);
968 		++num_clients;
969 	} else
970 		err(1, "accept");
971 }
972 
973 static void
974 event_loop(void)
975 {
976 	int rv;
977 	int fd;
978 	char buffer[DEVCTL_MAXBUF];
979 	int once = 0;
980 	int stream_fd, seqpacket_fd, max_fd;
981 	int accepting;
982 	timeval tv;
983 	fd_set fds;
984 
985 	fd = open(PATH_DEVCTL, O_RDONLY | O_CLOEXEC);
986 	if (fd == -1)
987 		err(1, "Can't open devctl device %s", PATH_DEVCTL);
988 	stream_fd = create_socket(STREAMPIPE, SOCK_STREAM);
989 	seqpacket_fd = create_socket(SEQPACKETPIPE, SOCK_SEQPACKET);
990 	accepting = 1;
991 	max_fd = max(fd, max(stream_fd, seqpacket_fd)) + 1;
992 	while (!romeo_must_die) {
993 		if (!once && !no_daemon && !daemonize_quick) {
994 			// Check to see if we have any events pending.
995 			tv.tv_sec = 0;
996 			tv.tv_usec = 0;
997 			FD_ZERO(&fds);
998 			FD_SET(fd, &fds);
999 			rv = select(fd + 1, &fds, &fds, &fds, &tv);
1000 			// No events -> we've processed all pending events
1001 			if (rv == 0) {
1002 				devdlog(LOG_DEBUG, "Calling daemon\n");
1003 				cfg.remove_pidfile();
1004 				cfg.open_pidfile();
1005 				daemon(0, 0);
1006 				cfg.write_pidfile();
1007 				once++;
1008 			}
1009 		}
1010 		/*
1011 		 * When we've already got the max number of clients, stop
1012 		 * accepting new connections (don't put the listening sockets in
1013 		 * the set), shrink the accept() queue to reject connections
1014 		 * quickly, and poll the existing clients more often, so that we
1015 		 * notice more quickly when any of them disappear to free up
1016 		 * client slots.
1017 		 */
1018 		FD_ZERO(&fds);
1019 		FD_SET(fd, &fds);
1020 		if (num_clients < max_clients) {
1021 			if (!accepting) {
1022 				listen(stream_fd, max_clients);
1023 				listen(seqpacket_fd, max_clients);
1024 				accepting = 1;
1025 			}
1026 			FD_SET(stream_fd, &fds);
1027 			FD_SET(seqpacket_fd, &fds);
1028 			tv.tv_sec = 60;
1029 			tv.tv_usec = 0;
1030 		} else {
1031 			if (accepting) {
1032 				listen(stream_fd, 0);
1033 				listen(seqpacket_fd, 0);
1034 				accepting = 0;
1035 			}
1036 			tv.tv_sec = 2;
1037 			tv.tv_usec = 0;
1038 		}
1039 		rv = select(max_fd, &fds, NULL, NULL, &tv);
1040 		if (got_siginfo) {
1041 			devdlog(LOG_NOTICE, "Events received so far=%u\n",
1042 			    total_events);
1043 			got_siginfo = 0;
1044 		}
1045 		if (rv == -1) {
1046 			if (errno == EINTR)
1047 				continue;
1048 			err(1, "select");
1049 		} else if (rv == 0)
1050 			check_clients();
1051 		if (FD_ISSET(fd, &fds)) {
1052 			rv = read(fd, buffer, sizeof(buffer) - 1);
1053 			if (rv > 0) {
1054 				total_events++;
1055 				if (rv == sizeof(buffer) - 1) {
1056 					devdlog(LOG_WARNING, "Warning: "
1057 					    "available event data exceeded "
1058 					    "buffer space\n");
1059 				}
1060 				notify_clients(buffer, rv);
1061 				buffer[rv] = '\0';
1062 				while (buffer[--rv] == '\n')
1063 					buffer[rv] = '\0';
1064 				try {
1065 					process_event(buffer);
1066 				}
1067 				catch (std::length_error e) {
1068 					devdlog(LOG_ERR, "Dropping event %s "
1069 					    "due to low memory", buffer);
1070 				}
1071 			} else if (rv < 0) {
1072 				if (errno != EINTR)
1073 					break;
1074 			} else {
1075 				/* EOF */
1076 				break;
1077 			}
1078 		}
1079 		if (FD_ISSET(stream_fd, &fds))
1080 			new_client(stream_fd, SOCK_STREAM);
1081 		/*
1082 		 * Aside from the socket type, both sockets use the same
1083 		 * protocol, so we can process clients the same way.
1084 		 */
1085 		if (FD_ISSET(seqpacket_fd, &fds))
1086 			new_client(seqpacket_fd, SOCK_SEQPACKET);
1087 	}
1088 	close(seqpacket_fd);
1089 	close(stream_fd);
1090 	close(fd);
1091 }
1092 
1093 /*
1094  * functions that the parser uses.
1095  */
1096 void
1097 add_attach(int prio, event_proc *p)
1098 {
1099 	cfg.add_attach(prio, p);
1100 }
1101 
1102 void
1103 add_detach(int prio, event_proc *p)
1104 {
1105 	cfg.add_detach(prio, p);
1106 }
1107 
1108 void
1109 add_directory(const char *dir)
1110 {
1111 	cfg.add_directory(dir);
1112 	free(const_cast<char *>(dir));
1113 }
1114 
1115 void
1116 add_nomatch(int prio, event_proc *p)
1117 {
1118 	cfg.add_nomatch(prio, p);
1119 }
1120 
1121 void
1122 add_notify(int prio, event_proc *p)
1123 {
1124 	cfg.add_notify(prio, p);
1125 }
1126 
1127 event_proc *
1128 add_to_event_proc(event_proc *ep, eps *eps)
1129 {
1130 	if (ep == NULL)
1131 		ep = new event_proc();
1132 	ep->add(eps);
1133 	return (ep);
1134 }
1135 
1136 eps *
1137 new_action(const char *cmd)
1138 {
1139 	eps *e = new action(cmd);
1140 	free(const_cast<char *>(cmd));
1141 	return (e);
1142 }
1143 
1144 eps *
1145 new_match(const char *var, const char *re)
1146 {
1147 	eps *e = new match(cfg, var, re);
1148 	free(const_cast<char *>(var));
1149 	free(const_cast<char *>(re));
1150 	return (e);
1151 }
1152 
1153 eps *
1154 new_media(const char *var, const char *re)
1155 {
1156 	eps *e = new media(cfg, var, re);
1157 	free(const_cast<char *>(var));
1158 	free(const_cast<char *>(re));
1159 	return (e);
1160 }
1161 
1162 void
1163 set_pidfile(const char *name)
1164 {
1165 	cfg.set_pidfile(name);
1166 	free(const_cast<char *>(name));
1167 }
1168 
1169 void
1170 set_variable(const char *var, const char *val)
1171 {
1172 	cfg.set_variable(var, val);
1173 	free(const_cast<char *>(var));
1174 	free(const_cast<char *>(val));
1175 }
1176 
1177 
1178 
1179 static void
1180 gensighand(int)
1181 {
1182 	romeo_must_die = 1;
1183 }
1184 
1185 /*
1186  * SIGINFO handler.  Will print useful statistics to the syslog or stderr
1187  * as appropriate
1188  */
1189 static void
1190 siginfohand(int)
1191 {
1192 	got_siginfo = 1;
1193 }
1194 
1195 /*
1196  * Local logging function.  Prints to syslog if we're daemonized; stderr
1197  * otherwise.
1198  */
1199 static void
1200 devdlog(int priority, const char* fmt, ...)
1201 {
1202 	va_list argp;
1203 
1204 	va_start(argp, fmt);
1205 	if (no_daemon)
1206 		vfprintf(stderr, fmt, argp);
1207 	else if (quiet_mode == 0 || priority <= LOG_WARNING)
1208 		vsyslog(priority, fmt, argp);
1209 	va_end(argp);
1210 }
1211 
1212 static void
1213 usage()
1214 {
1215 	fprintf(stderr, "usage: %s [-dnq] [-l connlimit] [-f file]\n",
1216 	    getprogname());
1217 	exit(1);
1218 }
1219 
1220 static void
1221 check_devd_enabled()
1222 {
1223 	int val = 0;
1224 	size_t len;
1225 
1226 	len = sizeof(val);
1227 	if (sysctlbyname(SYSCTL, &val, &len, NULL, 0) != 0)
1228 		errx(1, "devctl sysctl missing from kernel!");
1229 	if (val == 0) {
1230 		warnx("Setting " SYSCTL " to 1000");
1231 		val = 1000;
1232 		if (sysctlbyname(SYSCTL, NULL, NULL, &val, sizeof(val)))
1233 			err(1, "sysctlbyname");
1234 	}
1235 }
1236 
1237 /*
1238  * main
1239  */
1240 int
1241 main(int argc, char **argv)
1242 {
1243 	int ch;
1244 
1245 	check_devd_enabled();
1246 	while ((ch = getopt(argc, argv, "df:l:nq")) != -1) {
1247 		switch (ch) {
1248 		case 'd':
1249 			no_daemon = 1;
1250 			break;
1251 		case 'f':
1252 			configfile = optarg;
1253 			break;
1254 		case 'l':
1255 			max_clients = MAX(1, strtoul(optarg, NULL, 0));
1256 			break;
1257 		case 'n':
1258 			daemonize_quick = 1;
1259 			break;
1260 		case 'q':
1261 			quiet_mode = 1;
1262 			break;
1263 		default:
1264 			usage();
1265 		}
1266 	}
1267 
1268 	cfg.parse();
1269 	if (!no_daemon && daemonize_quick) {
1270 		cfg.open_pidfile();
1271 		daemon(0, 0);
1272 		cfg.write_pidfile();
1273 	}
1274 	signal(SIGPIPE, SIG_IGN);
1275 	signal(SIGHUP, gensighand);
1276 	signal(SIGINT, gensighand);
1277 	signal(SIGTERM, gensighand);
1278 	signal(SIGINFO, siginfohand);
1279 	event_loop();
1280 	return (0);
1281 }
1282