devd.cc revision 247758
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 * 4. 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: head/sbin/devd/devd.cc 247758 2013-03-04 02:21:19Z eadler $"); 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 <ctype.h> 77#include <dirent.h> 78#include <errno.h> 79#include <err.h> 80#include <fcntl.h> 81#include <libutil.h> 82#include <paths.h> 83#include <poll.h> 84#include <regex.h> 85#include <signal.h> 86#include <stdlib.h> 87#include <stdio.h> 88#include <string.h> 89#include <unistd.h> 90 91#include <algorithm> 92#include <map> 93#include <string> 94#include <list> 95#include <vector> 96 97#include "devd.h" /* C compatible definitions */ 98#include "devd.hh" /* C++ class definitions */ 99 100#define PIPE "/var/run/devd.pipe" 101#define CF "/etc/devd.conf" 102#define SYSCTL "hw.bus.devctl_disable" 103 104using namespace std; 105 106extern FILE *yyin; 107extern int lineno; 108 109static const char notify = '!'; 110static const char nomatch = '?'; 111static const char attach = '+'; 112static const char detach = '-'; 113 114static struct pidfh *pfh; 115 116int Dflag; 117int dflag; 118int nflag; 119static volatile sig_atomic_t romeo_must_die = 0; 120 121static const char *configfile = CF; 122 123static void event_loop(void); 124static void usage(void); 125 126template <class T> void 127delete_and_clear(vector<T *> &v) 128{ 129 typename vector<T *>::const_iterator i; 130 131 for (i = v.begin(); i != v.end(); ++i) 132 delete *i; 133 v.clear(); 134} 135 136config cfg; 137 138event_proc::event_proc() : _prio(-1) 139{ 140 _epsvec.reserve(4); 141} 142 143event_proc::~event_proc() 144{ 145 delete_and_clear(_epsvec); 146} 147 148void 149event_proc::add(eps *eps) 150{ 151 _epsvec.push_back(eps); 152} 153 154bool 155event_proc::matches(config &c) const 156{ 157 vector<eps *>::const_iterator i; 158 159 for (i = _epsvec.begin(); i != _epsvec.end(); ++i) 160 if (!(*i)->do_match(c)) 161 return (false); 162 return (true); 163} 164 165bool 166event_proc::run(config &c) const 167{ 168 vector<eps *>::const_iterator i; 169 170 for (i = _epsvec.begin(); i != _epsvec.end(); ++i) 171 if (!(*i)->do_action(c)) 172 return (false); 173 return (true); 174} 175 176action::action(const char *cmd) 177 : _cmd(cmd) 178{ 179 // nothing 180} 181 182action::~action() 183{ 184 // nothing 185} 186 187static int 188my_system(const char *command) 189{ 190 pid_t pid, savedpid; 191 int pstat; 192 struct sigaction ign, intact, quitact; 193 sigset_t newsigblock, oldsigblock; 194 195 if (!command) /* just checking... */ 196 return(1); 197 198 /* 199 * Ignore SIGINT and SIGQUIT, block SIGCHLD. Remember to save 200 * existing signal dispositions. 201 */ 202 ign.sa_handler = SIG_IGN; 203 ::sigemptyset(&ign.sa_mask); 204 ign.sa_flags = 0; 205 ::sigaction(SIGINT, &ign, &intact); 206 ::sigaction(SIGQUIT, &ign, &quitact); 207 ::sigemptyset(&newsigblock); 208 ::sigaddset(&newsigblock, SIGCHLD); 209 ::sigprocmask(SIG_BLOCK, &newsigblock, &oldsigblock); 210 switch (pid = ::fork()) { 211 case -1: /* error */ 212 break; 213 case 0: /* child */ 214 /* 215 * Restore original signal dispositions and exec the command. 216 */ 217 ::sigaction(SIGINT, &intact, NULL); 218 ::sigaction(SIGQUIT, &quitact, NULL); 219 ::sigprocmask(SIG_SETMASK, &oldsigblock, NULL); 220 /* 221 * Close the PID file, and all other open descriptors. 222 * Inherit std{in,out,err} only. 223 */ 224 cfg.close_pidfile(); 225 ::closefrom(3); 226 ::execl(_PATH_BSHELL, "sh", "-c", command, (char *)NULL); 227 ::_exit(127); 228 default: /* parent */ 229 savedpid = pid; 230 do { 231 pid = ::wait4(savedpid, &pstat, 0, (struct rusage *)0); 232 } while (pid == -1 && errno == EINTR); 233 break; 234 } 235 ::sigaction(SIGINT, &intact, NULL); 236 ::sigaction(SIGQUIT, &quitact, NULL); 237 ::sigprocmask(SIG_SETMASK, &oldsigblock, NULL); 238 return (pid == -1 ? -1 : pstat); 239} 240 241bool 242action::do_action(config &c) 243{ 244 string s = c.expand_string(_cmd.c_str()); 245 if (Dflag) 246 fprintf(stderr, "Executing '%s'\n", s.c_str()); 247 my_system(s.c_str()); 248 return (true); 249} 250 251match::match(config &c, const char *var, const char *re) : 252 _inv(re[0] == '!'), 253 _var(var), 254 _re(c.expand_string(_inv ? re + 1 : re, "^", "$")) 255{ 256 regcomp(&_regex, _re.c_str(), REG_EXTENDED | REG_NOSUB | REG_ICASE); 257} 258 259match::~match() 260{ 261 regfree(&_regex); 262} 263 264bool 265match::do_match(config &c) 266{ 267 const string &value = c.get_variable(_var); 268 bool retval; 269 270 if (Dflag) 271 fprintf(stderr, "Testing %s=%s against %s, invert=%d\n", 272 _var.c_str(), value.c_str(), _re.c_str(), _inv); 273 274 retval = (regexec(&_regex, value.c_str(), 0, NULL, 0) == 0); 275 if (_inv == 1) 276 retval = (retval == 0) ? 1 : 0; 277 278 return retval; 279} 280 281#include <sys/sockio.h> 282#include <net/if.h> 283#include <net/if_media.h> 284 285media::media(config &, const char *var, const char *type) 286 : _var(var), _type(-1) 287{ 288 static struct ifmedia_description media_types[] = { 289 { IFM_ETHER, "Ethernet" }, 290 { IFM_TOKEN, "Tokenring" }, 291 { IFM_FDDI, "FDDI" }, 292 { IFM_IEEE80211, "802.11" }, 293 { IFM_ATM, "ATM" }, 294 { -1, "unknown" }, 295 { 0, NULL }, 296 }; 297 for (int i = 0; media_types[i].ifmt_string != NULL; ++i) 298 if (strcasecmp(type, media_types[i].ifmt_string) == 0) { 299 _type = media_types[i].ifmt_word; 300 break; 301 } 302} 303 304media::~media() 305{ 306} 307 308bool 309media::do_match(config &c) 310{ 311 string value; 312 struct ifmediareq ifmr; 313 bool retval; 314 int s; 315 316 // Since we can be called from both a device attach/detach 317 // context where device-name is defined and what we want, 318 // as well as from a link status context, where subsystem is 319 // the name of interest, first try device-name and fall back 320 // to subsystem if none exists. 321 value = c.get_variable("device-name"); 322 if (value.length() == 0) 323 value = c.get_variable("subsystem"); 324 if (Dflag) 325 fprintf(stderr, "Testing media type of %s against 0x%x\n", 326 value.c_str(), _type); 327 328 retval = false; 329 330 s = socket(PF_INET, SOCK_DGRAM, 0); 331 if (s >= 0) { 332 memset(&ifmr, 0, sizeof(ifmr)); 333 strncpy(ifmr.ifm_name, value.c_str(), sizeof(ifmr.ifm_name)); 334 335 if (ioctl(s, SIOCGIFMEDIA, (caddr_t)&ifmr) >= 0 && 336 ifmr.ifm_status & IFM_AVALID) { 337 if (Dflag) 338 fprintf(stderr, "%s has media type 0x%x\n", 339 value.c_str(), IFM_TYPE(ifmr.ifm_active)); 340 retval = (IFM_TYPE(ifmr.ifm_active) == _type); 341 } else if (_type == -1) { 342 if (Dflag) 343 fprintf(stderr, "%s has unknown media type\n", 344 value.c_str()); 345 retval = true; 346 } 347 close(s); 348 } 349 350 return retval; 351} 352 353const string var_list::bogus = "_$_$_$_$_B_O_G_U_S_$_$_$_$_"; 354const string var_list::nothing = ""; 355 356const string & 357var_list::get_variable(const string &var) const 358{ 359 map<string, string>::const_iterator i; 360 361 i = _vars.find(var); 362 if (i == _vars.end()) 363 return (var_list::bogus); 364 return (i->second); 365} 366 367bool 368var_list::is_set(const string &var) const 369{ 370 return (_vars.find(var) != _vars.end()); 371} 372 373void 374var_list::set_variable(const string &var, const string &val) 375{ 376 if (Dflag) 377 fprintf(stderr, "setting %s=%s\n", var.c_str(), val.c_str()); 378 _vars[var] = val; 379} 380 381void 382config::reset(void) 383{ 384 _dir_list.clear(); 385 delete_and_clear(_var_list_table); 386 delete_and_clear(_attach_list); 387 delete_and_clear(_detach_list); 388 delete_and_clear(_nomatch_list); 389 delete_and_clear(_notify_list); 390} 391 392void 393config::parse_one_file(const char *fn) 394{ 395 if (Dflag) 396 fprintf(stderr, "Parsing %s\n", fn); 397 yyin = fopen(fn, "r"); 398 if (yyin == NULL) 399 err(1, "Cannot open config file %s", fn); 400 lineno = 1; 401 if (yyparse() != 0) 402 errx(1, "Cannot parse %s at line %d", fn, lineno); 403 fclose(yyin); 404} 405 406void 407config::parse_files_in_dir(const char *dirname) 408{ 409 DIR *dirp; 410 struct dirent *dp; 411 char path[PATH_MAX]; 412 413 if (Dflag) 414 fprintf(stderr, "Parsing files in %s\n", dirname); 415 dirp = opendir(dirname); 416 if (dirp == NULL) 417 return; 418 readdir(dirp); /* Skip . */ 419 readdir(dirp); /* Skip .. */ 420 while ((dp = readdir(dirp)) != NULL) { 421 if (strcmp(dp->d_name + dp->d_namlen - 5, ".conf") == 0) { 422 snprintf(path, sizeof(path), "%s/%s", 423 dirname, dp->d_name); 424 parse_one_file(path); 425 } 426 } 427 closedir(dirp); 428} 429 430class epv_greater { 431public: 432 int operator()(event_proc *const&l1, event_proc *const&l2) const 433 { 434 return (l1->get_priority() > l2->get_priority()); 435 } 436}; 437 438void 439config::sort_vector(vector<event_proc *> &v) 440{ 441 stable_sort(v.begin(), v.end(), epv_greater()); 442} 443 444void 445config::parse(void) 446{ 447 vector<string>::const_iterator i; 448 449 parse_one_file(configfile); 450 for (i = _dir_list.begin(); i != _dir_list.end(); ++i) 451 parse_files_in_dir((*i).c_str()); 452 sort_vector(_attach_list); 453 sort_vector(_detach_list); 454 sort_vector(_nomatch_list); 455 sort_vector(_notify_list); 456} 457 458void 459config::open_pidfile() 460{ 461 pid_t otherpid; 462 463 if (_pidfile.empty()) 464 return; 465 pfh = pidfile_open(_pidfile.c_str(), 0600, &otherpid); 466 if (pfh == NULL) { 467 if (errno == EEXIST) 468 errx(1, "devd already running, pid: %d", (int)otherpid); 469 warn("cannot open pid file"); 470 } 471} 472 473void 474config::write_pidfile() 475{ 476 477 pidfile_write(pfh); 478} 479 480void 481config::close_pidfile() 482{ 483 484 pidfile_close(pfh); 485} 486 487void 488config::remove_pidfile() 489{ 490 491 pidfile_remove(pfh); 492} 493 494void 495config::add_attach(int prio, event_proc *p) 496{ 497 p->set_priority(prio); 498 _attach_list.push_back(p); 499} 500 501void 502config::add_detach(int prio, event_proc *p) 503{ 504 p->set_priority(prio); 505 _detach_list.push_back(p); 506} 507 508void 509config::add_directory(const char *dir) 510{ 511 _dir_list.push_back(string(dir)); 512} 513 514void 515config::add_nomatch(int prio, event_proc *p) 516{ 517 p->set_priority(prio); 518 _nomatch_list.push_back(p); 519} 520 521void 522config::add_notify(int prio, event_proc *p) 523{ 524 p->set_priority(prio); 525 _notify_list.push_back(p); 526} 527 528void 529config::set_pidfile(const char *fn) 530{ 531 _pidfile = fn; 532} 533 534void 535config::push_var_table() 536{ 537 var_list *vl; 538 539 vl = new var_list(); 540 _var_list_table.push_back(vl); 541 if (Dflag) 542 fprintf(stderr, "Pushing table\n"); 543} 544 545void 546config::pop_var_table() 547{ 548 delete _var_list_table.back(); 549 _var_list_table.pop_back(); 550 if (Dflag) 551 fprintf(stderr, "Popping table\n"); 552} 553 554void 555config::set_variable(const char *var, const char *val) 556{ 557 _var_list_table.back()->set_variable(var, val); 558} 559 560const string & 561config::get_variable(const string &var) 562{ 563 vector<var_list *>::reverse_iterator i; 564 565 for (i = _var_list_table.rbegin(); i != _var_list_table.rend(); ++i) { 566 if ((*i)->is_set(var)) 567 return ((*i)->get_variable(var)); 568 } 569 return (var_list::nothing); 570} 571 572bool 573config::is_id_char(char ch) const 574{ 575 return (ch != '\0' && (isalpha(ch) || isdigit(ch) || ch == '_' || 576 ch == '-')); 577} 578 579void 580config::expand_one(const char *&src, string &dst) 581{ 582 int count; 583 string buffer; 584 585 src++; 586 // $$ -> $ 587 if (*src == '$') { 588 dst.append(src++, 1); 589 return; 590 } 591 592 // $(foo) -> $(foo) 593 // Not sure if I want to support this or not, so for now we just pass 594 // it through. 595 if (*src == '(') { 596 dst.append("$"); 597 count = 1; 598 /* If the string ends before ) is matched , return. */ 599 while (count > 0 && *src) { 600 if (*src == ')') 601 count--; 602 else if (*src == '(') 603 count++; 604 dst.append(src++, 1); 605 } 606 return; 607 } 608 609 // ${^A-Za-z] -> $\1 610 if (!isalpha(*src)) { 611 dst.append("$"); 612 dst.append(src++, 1); 613 return; 614 } 615 616 // $var -> replace with value 617 do { 618 buffer.append(src++, 1); 619 } while (is_id_char(*src)); 620 dst.append(get_variable(buffer)); 621} 622 623const string 624config::expand_string(const char *src, const char *prepend, const char *append) 625{ 626 const char *var_at; 627 string dst; 628 629 /* 630 * 128 bytes is enough for 2427 of 2438 expansions that happen 631 * while parsing config files, as tested on 2013-01-30. 632 */ 633 dst.reserve(128); 634 635 if (prepend != NULL) 636 dst = prepend; 637 638 for (;;) { 639 var_at = strchr(src, '$'); 640 if (var_at == NULL) { 641 dst.append(src); 642 break; 643 } 644 dst.append(src, var_at - src); 645 src = var_at; 646 expand_one(src, dst); 647 } 648 649 if (append != NULL) 650 dst.append(append); 651 652 return (dst); 653} 654 655bool 656config::chop_var(char *&buffer, char *&lhs, char *&rhs) const 657{ 658 char *walker; 659 660 if (*buffer == '\0') 661 return (false); 662 walker = lhs = buffer; 663 while (is_id_char(*walker)) 664 walker++; 665 if (*walker != '=') 666 return (false); 667 walker++; // skip = 668 if (*walker == '"') { 669 walker++; // skip " 670 rhs = walker; 671 while (*walker && *walker != '"') 672 walker++; 673 if (*walker != '"') 674 return (false); 675 rhs[-2] = '\0'; 676 *walker++ = '\0'; 677 } else { 678 rhs = walker; 679 while (*walker && !isspace(*walker)) 680 walker++; 681 if (*walker != '\0') 682 *walker++ = '\0'; 683 rhs[-1] = '\0'; 684 } 685 while (isspace(*walker)) 686 walker++; 687 buffer = walker; 688 return (true); 689} 690 691 692char * 693config::set_vars(char *buffer) 694{ 695 char *lhs; 696 char *rhs; 697 698 while (1) { 699 if (!chop_var(buffer, lhs, rhs)) 700 break; 701 set_variable(lhs, rhs); 702 } 703 return (buffer); 704} 705 706void 707config::find_and_execute(char type) 708{ 709 vector<event_proc *> *l; 710 vector<event_proc *>::const_iterator i; 711 const char *s; 712 713 switch (type) { 714 default: 715 return; 716 case notify: 717 l = &_notify_list; 718 s = "notify"; 719 break; 720 case nomatch: 721 l = &_nomatch_list; 722 s = "nomatch"; 723 break; 724 case attach: 725 l = &_attach_list; 726 s = "attach"; 727 break; 728 case detach: 729 l = &_detach_list; 730 s = "detach"; 731 break; 732 } 733 if (Dflag) 734 fprintf(stderr, "Processing %s event\n", s); 735 for (i = l->begin(); i != l->end(); ++i) { 736 if ((*i)->matches(*this)) { 737 (*i)->run(*this); 738 break; 739 } 740 } 741 742} 743 744 745static void 746process_event(char *buffer) 747{ 748 char type; 749 char *sp; 750 751 sp = buffer + 1; 752 if (Dflag) 753 fprintf(stderr, "Processing event '%s'\n", buffer); 754 type = *buffer++; 755 cfg.push_var_table(); 756 // No match doesn't have a device, and the format is a little 757 // different, so handle it separately. 758 switch (type) { 759 case notify: 760 sp = cfg.set_vars(sp); 761 break; 762 case nomatch: 763 //? at location pnp-info on bus 764 sp = strchr(sp, ' '); 765 if (sp == NULL) 766 return; /* Can't happen? */ 767 *sp++ = '\0'; 768 while (isspace(*sp)) 769 sp++; 770 if (strncmp(sp, "at ", 3) == 0) 771 sp += 3; 772 sp = cfg.set_vars(sp); 773 while (isspace(*sp)) 774 sp++; 775 if (strncmp(sp, "on ", 3) == 0) 776 cfg.set_variable("bus", sp + 3); 777 break; 778 case attach: /*FALLTHROUGH*/ 779 case detach: 780 sp = strchr(sp, ' '); 781 if (sp == NULL) 782 return; /* Can't happen? */ 783 *sp++ = '\0'; 784 cfg.set_variable("device-name", buffer); 785 while (isspace(*sp)) 786 sp++; 787 if (strncmp(sp, "at ", 3) == 0) 788 sp += 3; 789 sp = cfg.set_vars(sp); 790 while (isspace(*sp)) 791 sp++; 792 if (strncmp(sp, "on ", 3) == 0) 793 cfg.set_variable("bus", sp + 3); 794 break; 795 } 796 797 cfg.find_and_execute(type); 798 cfg.pop_var_table(); 799} 800 801int 802create_socket(const char *name) 803{ 804 int fd, slen; 805 struct sockaddr_un sun; 806 807 if ((fd = socket(PF_LOCAL, SOCK_STREAM, 0)) < 0) 808 err(1, "socket"); 809 bzero(&sun, sizeof(sun)); 810 sun.sun_family = AF_UNIX; 811 strlcpy(sun.sun_path, name, sizeof(sun.sun_path)); 812 slen = SUN_LEN(&sun); 813 unlink(name); 814 if (fcntl(fd, F_SETFL, O_NONBLOCK) < 0) 815 err(1, "fcntl"); 816 if (::bind(fd, (struct sockaddr *) & sun, slen) < 0) 817 err(1, "bind"); 818 listen(fd, 4); 819 chown(name, 0, 0); /* XXX - root.wheel */ 820 chmod(name, 0666); 821 return (fd); 822} 823 824unsigned int max_clients = 10; /* Default, can be overriden on cmdline. */ 825unsigned int num_clients; 826list<int> clients; 827 828void 829notify_clients(const char *data, int len) 830{ 831 list<int>::iterator i; 832 833 /* 834 * Deliver the data to all clients. Throw clients overboard at the 835 * first sign of trouble. This reaps clients who've died or closed 836 * their sockets, and also clients who are alive but failing to keep up 837 * (or who are maliciously not reading, to consume buffer space in 838 * kernel memory or tie up the limited number of available connections). 839 */ 840 for (i = clients.begin(); i != clients.end(); ) { 841 if (write(*i, data, len) != len) { 842 --num_clients; 843 close(*i); 844 i = clients.erase(i); 845 } else 846 ++i; 847 } 848} 849 850void 851check_clients(void) 852{ 853 int s; 854 struct pollfd pfd; 855 list<int>::iterator i; 856 857 /* 858 * Check all existing clients to see if any of them have disappeared. 859 * Normally we reap clients when we get an error trying to send them an 860 * event. This check eliminates the problem of an ever-growing list of 861 * zombie clients because we're never writing to them on a system 862 * without frequent device-change activity. 863 */ 864 pfd.events = 0; 865 for (i = clients.begin(); i != clients.end(); ) { 866 pfd.fd = *i; 867 s = poll(&pfd, 1, 0); 868 if ((s < 0 && s != EINTR ) || 869 (s > 0 && (pfd.revents & POLLHUP))) { 870 --num_clients; 871 close(*i); 872 i = clients.erase(i); 873 } else 874 ++i; 875 } 876} 877 878void 879new_client(int fd) 880{ 881 int s; 882 883 /* 884 * First go reap any zombie clients, then accept the connection, and 885 * shut down the read side to stop clients from consuming kernel memory 886 * by sending large buffers full of data we'll never read. 887 */ 888 check_clients(); 889 s = accept(fd, NULL, NULL); 890 if (s != -1) { 891 shutdown(s, SHUT_RD); 892 clients.push_back(s); 893 ++num_clients; 894 } 895} 896 897static void 898event_loop(void) 899{ 900 int rv; 901 int fd; 902 char buffer[DEVCTL_MAXBUF]; 903 int once = 0; 904 int server_fd, max_fd; 905 int accepting; 906 timeval tv; 907 fd_set fds; 908 909 fd = open(PATH_DEVCTL, O_RDONLY | O_CLOEXEC); 910 if (fd == -1) 911 err(1, "Can't open devctl device %s", PATH_DEVCTL); 912 server_fd = create_socket(PIPE); 913 accepting = 1; 914 max_fd = max(fd, server_fd) + 1; 915 while (!romeo_must_die) { 916 if (!once && !dflag && !nflag) { 917 // Check to see if we have any events pending. 918 tv.tv_sec = 0; 919 tv.tv_usec = 0; 920 FD_ZERO(&fds); 921 FD_SET(fd, &fds); 922 rv = select(fd + 1, &fds, &fds, &fds, &tv); 923 // No events -> we've processed all pending events 924 if (rv == 0) { 925 if (Dflag) 926 fprintf(stderr, "Calling daemon\n"); 927 cfg.remove_pidfile(); 928 cfg.open_pidfile(); 929 daemon(0, 0); 930 cfg.write_pidfile(); 931 once++; 932 } 933 } 934 /* 935 * When we've already got the max number of clients, stop 936 * accepting new connections (don't put server_fd in the set), 937 * shrink the accept() queue to reject connections quickly, and 938 * poll the existing clients more often, so that we notice more 939 * quickly when any of them disappear to free up client slots. 940 */ 941 FD_ZERO(&fds); 942 FD_SET(fd, &fds); 943 if (num_clients < max_clients) { 944 if (!accepting) { 945 listen(server_fd, max_clients); 946 accepting = 1; 947 } 948 FD_SET(server_fd, &fds); 949 tv.tv_sec = 60; 950 tv.tv_usec = 0; 951 } else { 952 if (accepting) { 953 listen(server_fd, 0); 954 accepting = 0; 955 } 956 tv.tv_sec = 2; 957 tv.tv_usec = 0; 958 } 959 rv = select(max_fd, &fds, NULL, NULL, &tv); 960 if (rv == -1) { 961 if (errno == EINTR) 962 continue; 963 err(1, "select"); 964 } else if (rv == 0) 965 check_clients(); 966 if (FD_ISSET(fd, &fds)) { 967 rv = read(fd, buffer, sizeof(buffer) - 1); 968 if (rv > 0) { 969 notify_clients(buffer, rv); 970 buffer[rv] = '\0'; 971 while (buffer[--rv] == '\n') 972 buffer[rv] = '\0'; 973 process_event(buffer); 974 } else if (rv < 0) { 975 if (errno != EINTR) 976 break; 977 } else { 978 /* EOF */ 979 break; 980 } 981 } 982 if (FD_ISSET(server_fd, &fds)) 983 new_client(server_fd); 984 } 985 close(fd); 986} 987 988/* 989 * functions that the parser uses. 990 */ 991void 992add_attach(int prio, event_proc *p) 993{ 994 cfg.add_attach(prio, p); 995} 996 997void 998add_detach(int prio, event_proc *p) 999{ 1000 cfg.add_detach(prio, p); 1001} 1002 1003void 1004add_directory(const char *dir) 1005{ 1006 cfg.add_directory(dir); 1007 free(const_cast<char *>(dir)); 1008} 1009 1010void 1011add_nomatch(int prio, event_proc *p) 1012{ 1013 cfg.add_nomatch(prio, p); 1014} 1015 1016void 1017add_notify(int prio, event_proc *p) 1018{ 1019 cfg.add_notify(prio, p); 1020} 1021 1022event_proc * 1023add_to_event_proc(event_proc *ep, eps *eps) 1024{ 1025 if (ep == NULL) 1026 ep = new event_proc(); 1027 ep->add(eps); 1028 return (ep); 1029} 1030 1031eps * 1032new_action(const char *cmd) 1033{ 1034 eps *e = new action(cmd); 1035 free(const_cast<char *>(cmd)); 1036 return (e); 1037} 1038 1039eps * 1040new_match(const char *var, const char *re) 1041{ 1042 eps *e = new match(cfg, var, re); 1043 free(const_cast<char *>(var)); 1044 free(const_cast<char *>(re)); 1045 return (e); 1046} 1047 1048eps * 1049new_media(const char *var, const char *re) 1050{ 1051 eps *e = new media(cfg, var, re); 1052 free(const_cast<char *>(var)); 1053 free(const_cast<char *>(re)); 1054 return (e); 1055} 1056 1057void 1058set_pidfile(const char *name) 1059{ 1060 cfg.set_pidfile(name); 1061 free(const_cast<char *>(name)); 1062} 1063 1064void 1065set_variable(const char *var, const char *val) 1066{ 1067 cfg.set_variable(var, val); 1068 free(const_cast<char *>(var)); 1069 free(const_cast<char *>(val)); 1070} 1071 1072 1073 1074static void 1075gensighand(int) 1076{ 1077 romeo_must_die = 1; 1078} 1079 1080static void 1081usage() 1082{ 1083 fprintf(stderr, "usage: %s [-Ddn] [-l connlimit] [-f file]\n", 1084 getprogname()); 1085 exit(1); 1086} 1087 1088static void 1089check_devd_enabled() 1090{ 1091 int val = 0; 1092 size_t len; 1093 1094 len = sizeof(val); 1095 if (sysctlbyname(SYSCTL, &val, &len, NULL, 0) != 0) 1096 errx(1, "devctl sysctl missing from kernel!"); 1097 if (val) { 1098 warnx("Setting " SYSCTL " to 0"); 1099 val = 0; 1100 sysctlbyname(SYSCTL, NULL, NULL, &val, sizeof(val)); 1101 } 1102} 1103 1104/* 1105 * main 1106 */ 1107int 1108main(int argc, char **argv) 1109{ 1110 int ch; 1111 1112 check_devd_enabled(); 1113 while ((ch = getopt(argc, argv, "Ddf:l:n")) != -1) { 1114 switch (ch) { 1115 case 'D': 1116 Dflag++; 1117 break; 1118 case 'd': 1119 dflag++; 1120 break; 1121 case 'f': 1122 configfile = optarg; 1123 break; 1124 case 'l': 1125 max_clients = MAX(1, strtoul(optarg, NULL, 0)); 1126 break; 1127 case 'n': 1128 nflag++; 1129 break; 1130 default: 1131 usage(); 1132 } 1133 } 1134 1135 cfg.parse(); 1136 if (!dflag && nflag) { 1137 cfg.open_pidfile(); 1138 daemon(0, 0); 1139 cfg.write_pidfile(); 1140 } 1141 signal(SIGPIPE, SIG_IGN); 1142 signal(SIGHUP, gensighand); 1143 signal(SIGINT, gensighand); 1144 signal(SIGTERM, gensighand); 1145 event_loop(); 1146 return (0); 1147} 1148