xref: /freebsd/sbin/devd/devd.cc (revision f0574f5cf69e168cc4ea71ebbe5fdec9ec9a3dfe)
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 /** fix_value
415  *
416  * Removes quoted characters that have made it this far. \" are
417  * converted to ". For all other characters, both \ and following
418  * character. So the string 'fre\:\"' is translated to 'fred\:"'.
419  */
420 const std::string &
421 var_list::fix_value(const std::string &val) const
422 {
423 	char *tmp, *dst;
424 	const char *src;
425 	std::string *rv;
426 
427 	dst = tmp = new char[val.length()];
428 	src = val.c_str();
429 	while (*src) {
430 		if (*src == '\\' && src[1] == '"')
431 			src++;
432 		else
433 			*dst++ = *src++;
434 	}
435 	rv = new string(tmp);
436 	delete tmp;
437 	return *rv;
438 }
439 
440 void
441 var_list::set_variable(const string &var, const string &val)
442 {
443 	/*
444 	 * This function gets called WAY too often to justify calling syslog()
445 	 * each time, even at LOG_DEBUG.  Because if syslogd isn't running, it
446 	 * can consume excessive amounts of systime inside of connect().  Only
447 	 * log when we're in -d mode.
448 	 */
449 	_vars[var] = fix_value(val);
450 	if (no_daemon)
451 		devdlog(LOG_DEBUG, "setting %s=%s\n", var.c_str(), val.c_str());
452 }
453 
454 void
455 config::reset(void)
456 {
457 	_dir_list.clear();
458 	delete_and_clear(_var_list_table);
459 	delete_and_clear(_attach_list);
460 	delete_and_clear(_detach_list);
461 	delete_and_clear(_nomatch_list);
462 	delete_and_clear(_notify_list);
463 }
464 
465 void
466 config::parse_one_file(const char *fn)
467 {
468 	devdlog(LOG_DEBUG, "Parsing %s\n", fn);
469 	yyin = fopen(fn, "r");
470 	if (yyin == NULL)
471 		err(1, "Cannot open config file %s", fn);
472 	lineno = 1;
473 	if (yyparse() != 0)
474 		errx(1, "Cannot parse %s at line %d", fn, lineno);
475 	fclose(yyin);
476 }
477 
478 void
479 config::parse_files_in_dir(const char *dirname)
480 {
481 	DIR *dirp;
482 	struct dirent *dp;
483 	char path[PATH_MAX];
484 
485 	devdlog(LOG_DEBUG, "Parsing files in %s\n", dirname);
486 	dirp = opendir(dirname);
487 	if (dirp == NULL)
488 		return;
489 	readdir(dirp);		/* Skip . */
490 	readdir(dirp);		/* Skip .. */
491 	while ((dp = readdir(dirp)) != NULL) {
492 		if (strcmp(dp->d_name + dp->d_namlen - 5, ".conf") == 0) {
493 			snprintf(path, sizeof(path), "%s/%s",
494 			    dirname, dp->d_name);
495 			parse_one_file(path);
496 		}
497 	}
498 	closedir(dirp);
499 }
500 
501 class epv_greater {
502 public:
503 	int operator()(event_proc *const&l1, event_proc *const&l2) const
504 	{
505 		return (l1->get_priority() > l2->get_priority());
506 	}
507 };
508 
509 void
510 config::sort_vector(vector<event_proc *> &v)
511 {
512 	stable_sort(v.begin(), v.end(), epv_greater());
513 }
514 
515 void
516 config::parse(void)
517 {
518 	vector<string>::const_iterator i;
519 
520 	parse_one_file(configfile);
521 	for (i = _dir_list.begin(); i != _dir_list.end(); ++i)
522 		parse_files_in_dir((*i).c_str());
523 	sort_vector(_attach_list);
524 	sort_vector(_detach_list);
525 	sort_vector(_nomatch_list);
526 	sort_vector(_notify_list);
527 }
528 
529 void
530 config::open_pidfile()
531 {
532 	pid_t otherpid;
533 
534 	if (_pidfile.empty())
535 		return;
536 	pfh = pidfile_open(_pidfile.c_str(), 0600, &otherpid);
537 	if (pfh == NULL) {
538 		if (errno == EEXIST)
539 			errx(1, "devd already running, pid: %d", (int)otherpid);
540 		warn("cannot open pid file");
541 	}
542 }
543 
544 void
545 config::write_pidfile()
546 {
547 
548 	pidfile_write(pfh);
549 }
550 
551 void
552 config::close_pidfile()
553 {
554 
555 	pidfile_close(pfh);
556 }
557 
558 void
559 config::remove_pidfile()
560 {
561 
562 	pidfile_remove(pfh);
563 }
564 
565 void
566 config::add_attach(int prio, event_proc *p)
567 {
568 	p->set_priority(prio);
569 	_attach_list.push_back(p);
570 }
571 
572 void
573 config::add_detach(int prio, event_proc *p)
574 {
575 	p->set_priority(prio);
576 	_detach_list.push_back(p);
577 }
578 
579 void
580 config::add_directory(const char *dir)
581 {
582 	_dir_list.push_back(string(dir));
583 }
584 
585 void
586 config::add_nomatch(int prio, event_proc *p)
587 {
588 	p->set_priority(prio);
589 	_nomatch_list.push_back(p);
590 }
591 
592 void
593 config::add_notify(int prio, event_proc *p)
594 {
595 	p->set_priority(prio);
596 	_notify_list.push_back(p);
597 }
598 
599 void
600 config::set_pidfile(const char *fn)
601 {
602 	_pidfile = fn;
603 }
604 
605 void
606 config::push_var_table()
607 {
608 	var_list *vl;
609 
610 	vl = new var_list();
611 	_var_list_table.push_back(vl);
612 	devdlog(LOG_DEBUG, "Pushing table\n");
613 }
614 
615 void
616 config::pop_var_table()
617 {
618 	delete _var_list_table.back();
619 	_var_list_table.pop_back();
620 	devdlog(LOG_DEBUG, "Popping table\n");
621 }
622 
623 void
624 config::set_variable(const char *var, const char *val)
625 {
626 	_var_list_table.back()->set_variable(var, val);
627 }
628 
629 const string &
630 config::get_variable(const string &var)
631 {
632 	vector<var_list *>::reverse_iterator i;
633 
634 	for (i = _var_list_table.rbegin(); i != _var_list_table.rend(); ++i) {
635 		if ((*i)->is_set(var))
636 			return ((*i)->get_variable(var));
637 	}
638 	return (var_list::nothing);
639 }
640 
641 bool
642 config::is_id_char(char ch) const
643 {
644 	return (ch != '\0' && (isalpha(ch) || isdigit(ch) || ch == '_' ||
645 	    ch == '-'));
646 }
647 
648 void
649 config::expand_one(const char *&src, string &dst)
650 {
651 	int count;
652 	string buffer;
653 
654 	src++;
655 	// $$ -> $
656 	if (*src == '$') {
657 		dst += *src++;
658 		return;
659 	}
660 
661 	// $(foo) -> $(foo)
662 	// Not sure if I want to support this or not, so for now we just pass
663 	// it through.
664 	if (*src == '(') {
665 		dst += '$';
666 		count = 1;
667 		/* If the string ends before ) is matched , return. */
668 		while (count > 0 && *src) {
669 			if (*src == ')')
670 				count--;
671 			else if (*src == '(')
672 				count++;
673 			dst += *src++;
674 		}
675 		return;
676 	}
677 
678 	// $[^-A-Za-z_*] -> $\1
679 	if (!isalpha(*src) && *src != '_' && *src != '-' && *src != '*') {
680 		dst += '$';
681 		dst += *src++;
682 		return;
683 	}
684 
685 	// $var -> replace with value
686 	do {
687 		buffer += *src++;
688 	} while (is_id_char(*src));
689 	dst.append(get_variable(buffer));
690 }
691 
692 const string
693 config::expand_string(const char *src, const char *prepend, const char *append)
694 {
695 	const char *var_at;
696 	string dst;
697 
698 	/*
699 	 * 128 bytes is enough for 2427 of 2438 expansions that happen
700 	 * while parsing config files, as tested on 2013-01-30.
701 	 */
702 	dst.reserve(128);
703 
704 	if (prepend != NULL)
705 		dst = prepend;
706 
707 	for (;;) {
708 		var_at = strchr(src, '$');
709 		if (var_at == NULL) {
710 			dst.append(src);
711 			break;
712 		}
713 		dst.append(src, var_at - src);
714 		src = var_at;
715 		expand_one(src, dst);
716 	}
717 
718 	if (append != NULL)
719 		dst.append(append);
720 
721 	return (dst);
722 }
723 
724 bool
725 config::chop_var(char *&buffer, char *&lhs, char *&rhs) const
726 {
727 	char *walker;
728 
729 	if (*buffer == '\0')
730 		return (false);
731 	walker = lhs = buffer;
732 	while (is_id_char(*walker))
733 		walker++;
734 	if (*walker != '=')
735 		return (false);
736 	walker++;		// skip =
737 	if (*walker == '"') {
738 		walker++;	// skip "
739 		rhs = walker;
740 		while (*walker && *walker != '"') {
741 			// Skip \" ... We leave it in the string and strip the \ later.
742 			// due to the super simplistic parser that we have here.
743 			if (*walker == '\\' && walker[1] == '"')
744 				walker++;
745 			walker++;
746 		}
747 		if (*walker != '"')
748 			return (false);
749 		rhs[-2] = '\0';
750 		*walker++ = '\0';
751 	} else {
752 		rhs = walker;
753 		while (*walker && !isspace(*walker))
754 			walker++;
755 		if (*walker != '\0')
756 			*walker++ = '\0';
757 		rhs[-1] = '\0';
758 	}
759 	while (isspace(*walker))
760 		walker++;
761 	buffer = walker;
762 	return (true);
763 }
764 
765 
766 char *
767 config::set_vars(char *buffer)
768 {
769 	char *lhs;
770 	char *rhs;
771 
772 	while (1) {
773 		if (!chop_var(buffer, lhs, rhs))
774 			break;
775 		set_variable(lhs, rhs);
776 	}
777 	return (buffer);
778 }
779 
780 void
781 config::find_and_execute(char type)
782 {
783 	vector<event_proc *> *l;
784 	vector<event_proc *>::const_iterator i;
785 	const char *s;
786 
787 	switch (type) {
788 	default:
789 		return;
790 	case notify:
791 		l = &_notify_list;
792 		s = "notify";
793 		break;
794 	case nomatch:
795 		l = &_nomatch_list;
796 		s = "nomatch";
797 		break;
798 	case attach:
799 		l = &_attach_list;
800 		s = "attach";
801 		break;
802 	case detach:
803 		l = &_detach_list;
804 		s = "detach";
805 		break;
806 	}
807 	devdlog(LOG_DEBUG, "Processing %s event\n", s);
808 	for (i = l->begin(); i != l->end(); ++i) {
809 		if ((*i)->matches(*this)) {
810 			(*i)->run(*this);
811 			break;
812 		}
813 	}
814 
815 }
816 
817 
818 static void
819 process_event(char *buffer)
820 {
821 	char type;
822 	char *sp;
823 	struct timeval tv;
824 	char *timestr;
825 
826 	sp = buffer + 1;
827 	devdlog(LOG_INFO, "Processing event '%s'\n", buffer);
828 	type = *buffer++;
829 	cfg.push_var_table();
830 	// $* is the entire line
831 	cfg.set_variable("*", buffer - 1);
832 	// $_ is the entire line without the initial character
833 	cfg.set_variable("_", buffer);
834 
835 	// Save the time this happened (as approximated by when we got
836 	// around to processing it).
837 	gettimeofday(&tv, NULL);
838 	asprintf(&timestr, "%jd.%06ld", (uintmax_t)tv.tv_sec, tv.tv_usec);
839 	cfg.set_variable("timestamp", timestr);
840 	free(timestr);
841 
842 	// Match doesn't have a device, and the format is a little
843 	// different, so handle it separately.
844 	switch (type) {
845 	case notify:
846 		//! (k=v)*
847 		sp = cfg.set_vars(sp);
848 		break;
849 	case nomatch:
850 		//? at location pnp-info on bus
851 		sp = strchr(sp, ' ');
852 		if (sp == NULL)
853 			return;	/* Can't happen? */
854 		*sp++ = '\0';
855 		while (isspace(*sp))
856 			sp++;
857 		if (strncmp(sp, "at ", 3) == 0)
858 			sp += 3;
859 		sp = cfg.set_vars(sp);
860 		while (isspace(*sp))
861 			sp++;
862 		if (strncmp(sp, "on ", 3) == 0)
863 			cfg.set_variable("bus", sp + 3);
864 		break;
865 	case attach:	/*FALLTHROUGH*/
866 	case detach:
867 		sp = strchr(sp, ' ');
868 		if (sp == NULL)
869 			return;	/* Can't happen? */
870 		*sp++ = '\0';
871 		cfg.set_variable("device-name", buffer);
872 		while (isspace(*sp))
873 			sp++;
874 		if (strncmp(sp, "at ", 3) == 0)
875 			sp += 3;
876 		sp = cfg.set_vars(sp);
877 		while (isspace(*sp))
878 			sp++;
879 		if (strncmp(sp, "on ", 3) == 0)
880 			cfg.set_variable("bus", sp + 3);
881 		break;
882 	}
883 
884 	cfg.find_and_execute(type);
885 	cfg.pop_var_table();
886 }
887 
888 int
889 create_socket(const char *name, int socktype)
890 {
891 	int fd, slen;
892 	struct sockaddr_un sun;
893 
894 	if ((fd = socket(PF_LOCAL, socktype, 0)) < 0)
895 		err(1, "socket");
896 	bzero(&sun, sizeof(sun));
897 	sun.sun_family = AF_UNIX;
898 	strlcpy(sun.sun_path, name, sizeof(sun.sun_path));
899 	slen = SUN_LEN(&sun);
900 	unlink(name);
901 	if (fcntl(fd, F_SETFL, O_NONBLOCK) < 0)
902 	    	err(1, "fcntl");
903 	if (::bind(fd, (struct sockaddr *) & sun, slen) < 0)
904 		err(1, "bind");
905 	listen(fd, 4);
906 	if (chown(name, 0, 0))	/* XXX - root.wheel */
907 		err(1, "chown");
908 	if (chmod(name, 0666))
909 		err(1, "chmod");
910 	return (fd);
911 }
912 
913 unsigned int max_clients = 10;	/* Default, can be overridden on cmdline. */
914 unsigned int num_clients;
915 
916 list<client_t> clients;
917 
918 void
919 notify_clients(const char *data, int len)
920 {
921 	list<client_t>::iterator i;
922 
923 	/*
924 	 * Deliver the data to all clients.  Throw clients overboard at the
925 	 * first sign of trouble.  This reaps clients who've died or closed
926 	 * their sockets, and also clients who are alive but failing to keep up
927 	 * (or who are maliciously not reading, to consume buffer space in
928 	 * kernel memory or tie up the limited number of available connections).
929 	 */
930 	for (i = clients.begin(); i != clients.end(); ) {
931 		int flags;
932 		if (i->socktype == SOCK_SEQPACKET)
933 			flags = MSG_EOR;
934 		else
935 			flags = 0;
936 
937 		if (send(i->fd, data, len, flags) != len) {
938 			--num_clients;
939 			close(i->fd);
940 			i = clients.erase(i);
941 			devdlog(LOG_WARNING, "notify_clients: send() failed; "
942 			    "dropping unresponsive client\n");
943 		} else
944 			++i;
945 	}
946 }
947 
948 void
949 check_clients(void)
950 {
951 	int s;
952 	struct pollfd pfd;
953 	list<client_t>::iterator i;
954 
955 	/*
956 	 * Check all existing clients to see if any of them have disappeared.
957 	 * Normally we reap clients when we get an error trying to send them an
958 	 * event.  This check eliminates the problem of an ever-growing list of
959 	 * zombie clients because we're never writing to them on a system
960 	 * without frequent device-change activity.
961 	 */
962 	pfd.events = 0;
963 	for (i = clients.begin(); i != clients.end(); ) {
964 		pfd.fd = i->fd;
965 		s = poll(&pfd, 1, 0);
966 		if ((s < 0 && s != EINTR ) ||
967 		    (s > 0 && (pfd.revents & POLLHUP))) {
968 			--num_clients;
969 			close(i->fd);
970 			i = clients.erase(i);
971 			devdlog(LOG_NOTICE, "check_clients:  "
972 			    "dropping disconnected client\n");
973 		} else
974 			++i;
975 	}
976 }
977 
978 void
979 new_client(int fd, int socktype)
980 {
981 	client_t s;
982 	int sndbuf_size;
983 
984 	/*
985 	 * First go reap any zombie clients, then accept the connection, and
986 	 * shut down the read side to stop clients from consuming kernel memory
987 	 * by sending large buffers full of data we'll never read.
988 	 */
989 	check_clients();
990 	s.socktype = socktype;
991 	s.fd = accept(fd, NULL, NULL);
992 	if (s.fd != -1) {
993 		sndbuf_size = CLIENT_BUFSIZE;
994 		if (setsockopt(s.fd, SOL_SOCKET, SO_SNDBUF, &sndbuf_size,
995 		    sizeof(sndbuf_size)))
996 			err(1, "setsockopt");
997 		shutdown(s.fd, SHUT_RD);
998 		clients.push_back(s);
999 		++num_clients;
1000 	} else
1001 		err(1, "accept");
1002 }
1003 
1004 static void
1005 event_loop(void)
1006 {
1007 	int rv;
1008 	int fd;
1009 	char buffer[DEVCTL_MAXBUF];
1010 	int once = 0;
1011 	int stream_fd, seqpacket_fd, max_fd;
1012 	int accepting;
1013 	timeval tv;
1014 	fd_set fds;
1015 
1016 	fd = open(PATH_DEVCTL, O_RDONLY | O_CLOEXEC);
1017 	if (fd == -1)
1018 		err(1, "Can't open devctl device %s", PATH_DEVCTL);
1019 	stream_fd = create_socket(STREAMPIPE, SOCK_STREAM);
1020 	seqpacket_fd = create_socket(SEQPACKETPIPE, SOCK_SEQPACKET);
1021 	accepting = 1;
1022 	max_fd = max(fd, max(stream_fd, seqpacket_fd)) + 1;
1023 	while (!romeo_must_die) {
1024 		if (!once && !no_daemon && !daemonize_quick) {
1025 			// Check to see if we have any events pending.
1026 			tv.tv_sec = 0;
1027 			tv.tv_usec = 0;
1028 			FD_ZERO(&fds);
1029 			FD_SET(fd, &fds);
1030 			rv = select(fd + 1, &fds, &fds, &fds, &tv);
1031 			// No events -> we've processed all pending events
1032 			if (rv == 0) {
1033 				devdlog(LOG_DEBUG, "Calling daemon\n");
1034 				cfg.remove_pidfile();
1035 				cfg.open_pidfile();
1036 				daemon(0, 0);
1037 				cfg.write_pidfile();
1038 				once++;
1039 			}
1040 		}
1041 		/*
1042 		 * When we've already got the max number of clients, stop
1043 		 * accepting new connections (don't put the listening sockets in
1044 		 * the set), shrink the accept() queue to reject connections
1045 		 * quickly, and poll the existing clients more often, so that we
1046 		 * notice more quickly when any of them disappear to free up
1047 		 * client slots.
1048 		 */
1049 		FD_ZERO(&fds);
1050 		FD_SET(fd, &fds);
1051 		if (num_clients < max_clients) {
1052 			if (!accepting) {
1053 				listen(stream_fd, max_clients);
1054 				listen(seqpacket_fd, max_clients);
1055 				accepting = 1;
1056 			}
1057 			FD_SET(stream_fd, &fds);
1058 			FD_SET(seqpacket_fd, &fds);
1059 			tv.tv_sec = 60;
1060 			tv.tv_usec = 0;
1061 		} else {
1062 			if (accepting) {
1063 				listen(stream_fd, 0);
1064 				listen(seqpacket_fd, 0);
1065 				accepting = 0;
1066 			}
1067 			tv.tv_sec = 2;
1068 			tv.tv_usec = 0;
1069 		}
1070 		rv = select(max_fd, &fds, NULL, NULL, &tv);
1071 		if (got_siginfo) {
1072 			devdlog(LOG_NOTICE, "Events received so far=%u\n",
1073 			    total_events);
1074 			got_siginfo = 0;
1075 		}
1076 		if (rv == -1) {
1077 			if (errno == EINTR)
1078 				continue;
1079 			err(1, "select");
1080 		} else if (rv == 0)
1081 			check_clients();
1082 		if (FD_ISSET(fd, &fds)) {
1083 			rv = read(fd, buffer, sizeof(buffer) - 1);
1084 			if (rv > 0) {
1085 				total_events++;
1086 				if (rv == sizeof(buffer) - 1) {
1087 					devdlog(LOG_WARNING, "Warning: "
1088 					    "available event data exceeded "
1089 					    "buffer space\n");
1090 				}
1091 				notify_clients(buffer, rv);
1092 				buffer[rv] = '\0';
1093 				while (buffer[--rv] == '\n')
1094 					buffer[rv] = '\0';
1095 				try {
1096 					process_event(buffer);
1097 				}
1098 				catch (std::length_error e) {
1099 					devdlog(LOG_ERR, "Dropping event %s "
1100 					    "due to low memory", buffer);
1101 				}
1102 			} else if (rv < 0) {
1103 				if (errno != EINTR)
1104 					break;
1105 			} else {
1106 				/* EOF */
1107 				break;
1108 			}
1109 		}
1110 		if (FD_ISSET(stream_fd, &fds))
1111 			new_client(stream_fd, SOCK_STREAM);
1112 		/*
1113 		 * Aside from the socket type, both sockets use the same
1114 		 * protocol, so we can process clients the same way.
1115 		 */
1116 		if (FD_ISSET(seqpacket_fd, &fds))
1117 			new_client(seqpacket_fd, SOCK_SEQPACKET);
1118 	}
1119 	close(seqpacket_fd);
1120 	close(stream_fd);
1121 	close(fd);
1122 }
1123 
1124 /*
1125  * functions that the parser uses.
1126  */
1127 void
1128 add_attach(int prio, event_proc *p)
1129 {
1130 	cfg.add_attach(prio, p);
1131 }
1132 
1133 void
1134 add_detach(int prio, event_proc *p)
1135 {
1136 	cfg.add_detach(prio, p);
1137 }
1138 
1139 void
1140 add_directory(const char *dir)
1141 {
1142 	cfg.add_directory(dir);
1143 	free(const_cast<char *>(dir));
1144 }
1145 
1146 void
1147 add_nomatch(int prio, event_proc *p)
1148 {
1149 	cfg.add_nomatch(prio, p);
1150 }
1151 
1152 void
1153 add_notify(int prio, event_proc *p)
1154 {
1155 	cfg.add_notify(prio, p);
1156 }
1157 
1158 event_proc *
1159 add_to_event_proc(event_proc *ep, eps *eps)
1160 {
1161 	if (ep == NULL)
1162 		ep = new event_proc();
1163 	ep->add(eps);
1164 	return (ep);
1165 }
1166 
1167 eps *
1168 new_action(const char *cmd)
1169 {
1170 	eps *e = new action(cmd);
1171 	free(const_cast<char *>(cmd));
1172 	return (e);
1173 }
1174 
1175 eps *
1176 new_match(const char *var, const char *re)
1177 {
1178 	eps *e = new match(cfg, var, re);
1179 	free(const_cast<char *>(var));
1180 	free(const_cast<char *>(re));
1181 	return (e);
1182 }
1183 
1184 eps *
1185 new_media(const char *var, const char *re)
1186 {
1187 	eps *e = new media(cfg, var, re);
1188 	free(const_cast<char *>(var));
1189 	free(const_cast<char *>(re));
1190 	return (e);
1191 }
1192 
1193 void
1194 set_pidfile(const char *name)
1195 {
1196 	cfg.set_pidfile(name);
1197 	free(const_cast<char *>(name));
1198 }
1199 
1200 void
1201 set_variable(const char *var, const char *val)
1202 {
1203 	cfg.set_variable(var, val);
1204 	free(const_cast<char *>(var));
1205 	free(const_cast<char *>(val));
1206 }
1207 
1208 
1209 
1210 static void
1211 gensighand(int)
1212 {
1213 	romeo_must_die = 1;
1214 }
1215 
1216 /*
1217  * SIGINFO handler.  Will print useful statistics to the syslog or stderr
1218  * as appropriate
1219  */
1220 static void
1221 siginfohand(int)
1222 {
1223 	got_siginfo = 1;
1224 }
1225 
1226 /*
1227  * Local logging function.  Prints to syslog if we're daemonized; stderr
1228  * otherwise.
1229  */
1230 static void
1231 devdlog(int priority, const char* fmt, ...)
1232 {
1233 	va_list argp;
1234 
1235 	va_start(argp, fmt);
1236 	if (no_daemon)
1237 		vfprintf(stderr, fmt, argp);
1238 	else if (quiet_mode == 0 || priority <= LOG_WARNING)
1239 		vsyslog(priority, fmt, argp);
1240 	va_end(argp);
1241 }
1242 
1243 static void
1244 usage()
1245 {
1246 	fprintf(stderr, "usage: %s [-dnq] [-l connlimit] [-f file]\n",
1247 	    getprogname());
1248 	exit(1);
1249 }
1250 
1251 static void
1252 check_devd_enabled()
1253 {
1254 	int val = 0;
1255 	size_t len;
1256 
1257 	len = sizeof(val);
1258 	if (sysctlbyname(SYSCTL, &val, &len, NULL, 0) != 0)
1259 		errx(1, "devctl sysctl missing from kernel!");
1260 	if (val == 0) {
1261 		warnx("Setting " SYSCTL " to 1000");
1262 		val = 1000;
1263 		if (sysctlbyname(SYSCTL, NULL, NULL, &val, sizeof(val)))
1264 			err(1, "sysctlbyname");
1265 	}
1266 }
1267 
1268 /*
1269  * main
1270  */
1271 int
1272 main(int argc, char **argv)
1273 {
1274 	int ch;
1275 
1276 	check_devd_enabled();
1277 	while ((ch = getopt(argc, argv, "df:l:nq")) != -1) {
1278 		switch (ch) {
1279 		case 'd':
1280 			no_daemon = 1;
1281 			break;
1282 		case 'f':
1283 			configfile = optarg;
1284 			break;
1285 		case 'l':
1286 			max_clients = MAX(1, strtoul(optarg, NULL, 0));
1287 			break;
1288 		case 'n':
1289 			daemonize_quick = 1;
1290 			break;
1291 		case 'q':
1292 			quiet_mode = 1;
1293 			break;
1294 		default:
1295 			usage();
1296 		}
1297 	}
1298 
1299 	cfg.parse();
1300 	if (!no_daemon && daemonize_quick) {
1301 		cfg.open_pidfile();
1302 		daemon(0, 0);
1303 		cfg.write_pidfile();
1304 	}
1305 	signal(SIGPIPE, SIG_IGN);
1306 	signal(SIGHUP, gensighand);
1307 	signal(SIGINT, gensighand);
1308 	signal(SIGTERM, gensighand);
1309 	signal(SIGINFO, siginfohand);
1310 	event_loop();
1311 	return (0);
1312 }
1313