1 /* 2 * Copyright (c) 1983, 1993 3 * The Regents of the University of California. 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 * 3. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by the University of 16 * California, Berkeley and its contributors. 17 * 4. Neither the name of the University nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 */ 33 34 #ifndef lint 35 static char copyright[] = 36 "@(#) Copyright (c) 1983, 1993\n\ 37 The Regents of the University of California. All rights reserved.\n"; 38 #endif /* not lint */ 39 40 #ifndef lint 41 static char sccsid[] = "@(#)rwhod.c 8.1 (Berkeley) 6/6/93"; 42 #endif /* not lint */ 43 44 #include <sys/param.h> 45 #include <sys/socket.h> 46 #include <sys/stat.h> 47 #include <sys/signal.h> 48 #include <sys/ioctl.h> 49 #include <sys/sysctl.h> 50 51 #include <net/if.h> 52 #include <net/if_dl.h> 53 #include <net/route.h> 54 #include <netinet/in.h> 55 #include <protocols/rwhod.h> 56 57 #include <ctype.h> 58 #include <errno.h> 59 #include <fcntl.h> 60 #include <netdb.h> 61 #include <paths.h> 62 #include <stdio.h> 63 #include <stdlib.h> 64 #include <string.h> 65 #include <syslog.h> 66 #include <unistd.h> 67 #include <utmp.h> 68 69 /* 70 * Alarm interval. Don't forget to change the down time check in ruptime 71 * if this is changed. 72 */ 73 #define AL_INTERVAL (3 * 60) 74 75 char myname[MAXHOSTNAMELEN]; 76 77 /* 78 * We communicate with each neighbor in a list constructed at the time we're 79 * started up. Neighbors are currently directly connected via a hardware 80 * interface. 81 */ 82 struct neighbor { 83 struct neighbor *n_next; 84 char *n_name; /* interface name */ 85 struct sockaddr *n_addr; /* who to send to */ 86 int n_addrlen; /* size of address */ 87 int n_flags; /* should forward?, interface flags */ 88 }; 89 90 struct neighbor *neighbors; 91 struct whod mywd; 92 struct servent *sp; 93 int s, utmpf; 94 95 #define WHDRSIZE (sizeof(mywd) - sizeof(mywd.wd_we)) 96 97 int configure __P((int)); 98 void getboottime __P((int)); 99 void onalrm __P((int)); 100 void quit __P((char *)); 101 void rt_xaddrs __P((caddr_t, caddr_t, struct rt_addrinfo *)); 102 int verify __P((char *)); 103 #ifdef DEBUG 104 char *interval __P((int, char *)); 105 void Sendto __P((int, char *, int, int, char *, int)); 106 #define sendto Sendto 107 #endif 108 109 int 110 main(argc, argv) 111 int argc; 112 char argv[]; 113 { 114 struct sockaddr_in from; 115 struct stat st; 116 char path[64]; 117 int on = 1; 118 char *cp; 119 struct sockaddr_in sin; 120 121 if (getuid()) { 122 fprintf(stderr, "rwhod: not super user\n"); 123 exit(1); 124 } 125 sp = getservbyname("who", "udp"); 126 if (sp == NULL) { 127 fprintf(stderr, "rwhod: udp/who: unknown service\n"); 128 exit(1); 129 } 130 #ifndef DEBUG 131 daemon(1, 0); 132 #endif 133 if (chdir(_PATH_RWHODIR) < 0) { 134 (void)fprintf(stderr, "rwhod: %s: %s\n", 135 _PATH_RWHODIR, strerror(errno)); 136 exit(1); 137 } 138 (void) signal(SIGHUP, getboottime); 139 openlog("rwhod", LOG_PID, LOG_DAEMON); 140 /* 141 * Establish host name as returned by system. 142 */ 143 if (gethostname(myname, sizeof(myname) - 1) < 0) { 144 syslog(LOG_ERR, "gethostname: %m"); 145 exit(1); 146 } 147 if ((cp = index(myname, '.')) != NULL) 148 *cp = '\0'; 149 strncpy(mywd.wd_hostname, myname, sizeof(myname) - 1); 150 utmpf = open(_PATH_UTMP, O_RDONLY|O_CREAT, 0644); 151 if (utmpf < 0) { 152 syslog(LOG_ERR, "%s: %m", _PATH_UTMP); 153 exit(1); 154 } 155 getboottime(0); 156 if ((s = socket(AF_INET, SOCK_DGRAM, 0)) < 0) { 157 syslog(LOG_ERR, "socket: %m"); 158 exit(1); 159 } 160 if (setsockopt(s, SOL_SOCKET, SO_BROADCAST, &on, sizeof(on)) < 0) { 161 syslog(LOG_ERR, "setsockopt SO_BROADCAST: %m"); 162 exit(1); 163 } 164 memset(&sin, 0, sizeof(sin)); 165 sin.sin_family = AF_INET; 166 sin.sin_port = sp->s_port; 167 if (bind(s, (struct sockaddr *)&sin, sizeof(sin)) < 0) { 168 syslog(LOG_ERR, "bind: %m"); 169 exit(1); 170 } 171 if (!configure(s)) 172 exit(1); 173 signal(SIGALRM, onalrm); 174 onalrm(0); 175 for (;;) { 176 struct whod wd; 177 int cc, whod, len = sizeof(from); 178 179 cc = recvfrom(s, (char *)&wd, sizeof(struct whod), 0, 180 (struct sockaddr *)&from, &len); 181 if (cc <= 0) { 182 if (cc < 0 && errno != EINTR) 183 syslog(LOG_WARNING, "recv: %m"); 184 continue; 185 } 186 if (from.sin_port != sp->s_port) { 187 syslog(LOG_WARNING, "%d: bad from port", 188 ntohs(from.sin_port)); 189 continue; 190 } 191 if (wd.wd_vers != WHODVERSION) 192 continue; 193 if (wd.wd_type != WHODTYPE_STATUS) 194 continue; 195 if (!verify(wd.wd_hostname)) { 196 syslog(LOG_WARNING, "malformed host name from %x", 197 from.sin_addr); 198 continue; 199 } 200 (void) sprintf(path, "whod.%s", wd.wd_hostname); 201 /* 202 * Rather than truncating and growing the file each time, 203 * use ftruncate if size is less than previous size. 204 */ 205 whod = open(path, O_WRONLY | O_CREAT, 0644); 206 if (whod < 0) { 207 syslog(LOG_WARNING, "%s: %m", path); 208 continue; 209 } 210 #if ENDIAN != BIG_ENDIAN 211 { 212 int i, n = (cc - WHDRSIZE)/sizeof(struct whoent); 213 struct whoent *we; 214 215 /* undo header byte swapping before writing to file */ 216 wd.wd_sendtime = ntohl(wd.wd_sendtime); 217 for (i = 0; i < 3; i++) 218 wd.wd_loadav[i] = ntohl(wd.wd_loadav[i]); 219 wd.wd_boottime = ntohl(wd.wd_boottime); 220 we = wd.wd_we; 221 for (i = 0; i < n; i++) { 222 we->we_idle = ntohl(we->we_idle); 223 we->we_utmp.out_time = 224 ntohl(we->we_utmp.out_time); 225 we++; 226 } 227 } 228 #endif 229 (void) time((time_t *)&wd.wd_recvtime); 230 (void) write(whod, (char *)&wd, cc); 231 if (fstat(whod, &st) < 0 || st.st_size > cc) 232 ftruncate(whod, cc); 233 (void) close(whod); 234 } 235 } 236 237 /* 238 * Check out host name for unprintables 239 * and other funnies before allowing a file 240 * to be created. Sorry, but blanks aren't allowed. 241 */ 242 int 243 verify(name) 244 register char *name; 245 { 246 register int size = 0; 247 248 while (*name) { 249 if (!isascii(*name) || !(isalnum(*name) || ispunct(*name))) 250 return (0); 251 name++, size++; 252 } 253 return (size > 0); 254 } 255 256 int utmptime; 257 int utmpent; 258 int utmpsize = 0; 259 struct utmp *utmp; 260 int alarmcount; 261 262 void 263 onalrm(signo) 264 int signo; 265 { 266 register struct neighbor *np; 267 register struct whoent *we = mywd.wd_we, *wlast; 268 register int i; 269 struct stat stb; 270 double avenrun[3]; 271 time_t now; 272 int cc; 273 274 now = time(NULL); 275 if (alarmcount % 10 == 0) 276 getboottime(0); 277 alarmcount++; 278 (void) fstat(utmpf, &stb); 279 if ((stb.st_mtime != utmptime) || (stb.st_size > utmpsize)) { 280 utmptime = stb.st_mtime; 281 if (stb.st_size > utmpsize) { 282 utmpsize = stb.st_size + 10 * sizeof(struct utmp); 283 if (utmp) 284 utmp = (struct utmp *)realloc(utmp, utmpsize); 285 else 286 utmp = (struct utmp *)malloc(utmpsize); 287 if (! utmp) { 288 fprintf(stderr, "rwhod: malloc failed\n"); 289 utmpsize = 0; 290 goto done; 291 } 292 } 293 (void) lseek(utmpf, (off_t)0, L_SET); 294 cc = read(utmpf, (char *)utmp, stb.st_size); 295 if (cc < 0) { 296 fprintf(stderr, "rwhod: %s: %s\n", 297 _PATH_UTMP, strerror(errno)); 298 goto done; 299 } 300 wlast = &mywd.wd_we[1024 / sizeof(struct whoent) - 1]; 301 utmpent = cc / sizeof(struct utmp); 302 for (i = 0; i < utmpent; i++) 303 if (utmp[i].ut_name[0]) { 304 memcpy(we->we_utmp.out_line, utmp[i].ut_line, 305 sizeof(utmp[i].ut_line)); 306 memcpy(we->we_utmp.out_name, utmp[i].ut_name, 307 sizeof(utmp[i].ut_name)); 308 we->we_utmp.out_time = htonl(utmp[i].ut_time); 309 if (we >= wlast) 310 break; 311 we++; 312 } 313 utmpent = we - mywd.wd_we; 314 } 315 316 /* 317 * The test on utmpent looks silly---after all, if no one is 318 * logged on, why worry about efficiency?---but is useful on 319 * (e.g.) compute servers. 320 */ 321 if (utmpent && chdir(_PATH_DEV)) { 322 syslog(LOG_ERR, "chdir(%s): %m", _PATH_DEV); 323 exit(1); 324 } 325 we = mywd.wd_we; 326 for (i = 0; i < utmpent; i++) { 327 if (stat(we->we_utmp.out_line, &stb) >= 0) 328 we->we_idle = htonl(now - stb.st_atime); 329 we++; 330 } 331 (void)getloadavg(avenrun, sizeof(avenrun)/sizeof(avenrun[0])); 332 for (i = 0; i < 3; i++) 333 mywd.wd_loadav[i] = htonl((u_long)(avenrun[i] * 100)); 334 cc = (char *)we - (char *)&mywd; 335 mywd.wd_sendtime = htonl(time(0)); 336 mywd.wd_vers = WHODVERSION; 337 mywd.wd_type = WHODTYPE_STATUS; 338 for (np = neighbors; np != NULL; np = np->n_next) 339 (void)sendto(s, (char *)&mywd, cc, 0, 340 np->n_addr, np->n_addrlen); 341 if (utmpent && chdir(_PATH_RWHODIR)) { 342 syslog(LOG_ERR, "chdir(%s): %m", _PATH_RWHODIR); 343 exit(1); 344 } 345 done: 346 (void) alarm(AL_INTERVAL); 347 } 348 349 void 350 getboottime(signo) 351 int signo; 352 { 353 int mib[2]; 354 size_t size; 355 struct timeval tm; 356 357 mib[0] = CTL_KERN; 358 mib[1] = KERN_BOOTTIME; 359 size = sizeof(tm); 360 if (sysctl(mib, 2, &tm, &size, NULL, 0) == -1) { 361 syslog(LOG_ERR, "cannot get boottime: %m"); 362 exit(1); 363 } 364 mywd.wd_boottime = htonl(tm.tv_sec); 365 } 366 367 void 368 quit(msg) 369 char *msg; 370 { 371 syslog(LOG_ERR, msg); 372 exit(1); 373 } 374 375 #define ROUNDUP(a) \ 376 ((a) > 0 ? (1 + (((a) - 1) | (sizeof(long) - 1))) : sizeof(long)) 377 #define ADVANCE(x, n) (x += ROUNDUP((n)->sa_len)) 378 379 void 380 rt_xaddrs(cp, cplim, rtinfo) 381 register caddr_t cp, cplim; 382 register struct rt_addrinfo *rtinfo; 383 { 384 register struct sockaddr *sa; 385 register int i; 386 387 memset(rtinfo->rti_info, 0, sizeof(rtinfo->rti_info)); 388 for (i = 0; (i < RTAX_MAX) && (cp < cplim); i++) { 389 if ((rtinfo->rti_addrs & (1 << i)) == 0) 390 continue; 391 rtinfo->rti_info[i] = sa = (struct sockaddr *)cp; 392 ADVANCE(cp, sa); 393 } 394 } 395 396 /* 397 * Figure out device configuration and select 398 * networks which deserve status information. 399 */ 400 int 401 configure(s) 402 int s; 403 { 404 register struct neighbor *np; 405 register struct if_msghdr *ifm; 406 register struct ifa_msghdr *ifam; 407 struct sockaddr_dl *sdl; 408 size_t needed; 409 int mib[6], flags = 0, len; 410 char *buf, *lim, *next; 411 struct rt_addrinfo info; 412 413 mib[0] = CTL_NET; 414 mib[1] = PF_ROUTE; 415 mib[2] = 0; 416 mib[3] = AF_INET; 417 mib[4] = NET_RT_IFLIST; 418 mib[5] = 0; 419 if (sysctl(mib, 6, NULL, &needed, NULL, 0) < 0) 420 quit("route-sysctl-estimate"); 421 if ((buf = malloc(needed)) == NULL) 422 quit("malloc"); 423 if (sysctl(mib, 6, buf, &needed, NULL, 0) < 0) 424 quit("actual retrieval of interface table"); 425 lim = buf + needed; 426 427 sdl = NULL; /* XXX just to keep gcc -Wall happy */ 428 for (next = buf; next < lim; next += ifm->ifm_msglen) { 429 ifm = (struct if_msghdr *)next; 430 if (ifm->ifm_type == RTM_IFINFO) { 431 sdl = (struct sockaddr_dl *)(ifm + 1); 432 flags = ifm->ifm_flags; 433 continue; 434 } 435 if ((flags & IFF_UP) == 0 || 436 (flags & (IFF_BROADCAST|IFF_POINTOPOINT)) == 0) 437 continue; 438 if (ifm->ifm_type != RTM_NEWADDR) 439 quit("out of sync parsing NET_RT_IFLIST"); 440 ifam = (struct ifa_msghdr *)ifm; 441 info.rti_addrs = ifam->ifam_addrs; 442 rt_xaddrs((char *)(ifam + 1), ifam->ifam_msglen + (char *)ifam, 443 &info); 444 /* gag, wish we could get rid of Internet dependencies */ 445 #define dstaddr info.rti_info[RTAX_BRD] 446 #define IPADDR_SA(x) ((struct sockaddr_in *)(x))->sin_addr.s_addr 447 #define PORT_SA(x) ((struct sockaddr_in *)(x))->sin_port 448 if (dstaddr == 0 || dstaddr->sa_family != AF_INET) 449 continue; 450 PORT_SA(dstaddr) = sp->s_port; 451 for (np = neighbors; np != NULL; np = np->n_next) 452 if (memcmp(sdl->sdl_data, np->n_name, 453 sdl->sdl_nlen) == 0 && 454 IPADDR_SA(np->n_addr) == IPADDR_SA(dstaddr)) 455 break; 456 if (np != NULL) 457 continue; 458 len = sizeof(*np) + dstaddr->sa_len + sdl->sdl_nlen + 1; 459 np = (struct neighbor *)malloc(len); 460 if (np == NULL) 461 quit("malloc of neighbor structure"); 462 memset(np, 0, len); 463 np->n_flags = flags; 464 np->n_addr = (struct sockaddr *)(np + 1); 465 np->n_addrlen = dstaddr->sa_len; 466 np->n_name = np->n_addrlen + (char *)np->n_addr; 467 np->n_next = neighbors; 468 neighbors = np; 469 memcpy((char *)np->n_addr, (char *)dstaddr, np->n_addrlen); 470 memcpy(np->n_name, sdl->sdl_data, sdl->sdl_nlen); 471 } 472 free(buf); 473 return (1); 474 } 475 476 #ifdef DEBUG 477 void 478 Sendto(s, buf, cc, flags, to, tolen) 479 int s; 480 char *buf; 481 int cc, flags; 482 char *to; 483 int tolen; 484 { 485 register struct whod *w = (struct whod *)buf; 486 register struct whoent *we; 487 struct sockaddr_in *sin = (struct sockaddr_in *)to; 488 489 printf("sendto %x.%d\n", ntohl(sin->sin_addr), ntohs(sin->sin_port)); 490 printf("hostname %s %s\n", w->wd_hostname, 491 interval(ntohl(w->wd_sendtime) - ntohl(w->wd_boottime), " up")); 492 printf("load %4.2f, %4.2f, %4.2f\n", 493 ntohl(w->wd_loadav[0]) / 100.0, ntohl(w->wd_loadav[1]) / 100.0, 494 ntohl(w->wd_loadav[2]) / 100.0); 495 cc -= WHDRSIZE; 496 for (we = w->wd_we, cc /= sizeof(struct whoent); cc > 0; cc--, we++) { 497 time_t t = ntohl(we->we_utmp.out_time); 498 printf("%-8.8s %s:%s %.12s", 499 we->we_utmp.out_name, 500 w->wd_hostname, we->we_utmp.out_line, 501 ctime(&t)+4); 502 we->we_idle = ntohl(we->we_idle) / 60; 503 if (we->we_idle) { 504 if (we->we_idle >= 100*60) 505 we->we_idle = 100*60 - 1; 506 if (we->we_idle >= 60) 507 printf(" %2d", we->we_idle / 60); 508 else 509 printf(" "); 510 printf(":%02d", we->we_idle % 60); 511 } 512 printf("\n"); 513 } 514 } 515 516 char * 517 interval(time, updown) 518 int time; 519 char *updown; 520 { 521 static char resbuf[32]; 522 int days, hours, minutes; 523 524 if (time < 0 || time > 3*30*24*60*60) { 525 (void) sprintf(resbuf, " %s ??:??", updown); 526 return (resbuf); 527 } 528 minutes = (time + 59) / 60; /* round to minutes */ 529 hours = minutes / 60; minutes %= 60; 530 days = hours / 24; hours %= 24; 531 if (days) 532 (void) sprintf(resbuf, "%s %2d+%02d:%02d", 533 updown, days, hours, minutes); 534 else 535 (void) sprintf(resbuf, "%s %2d:%02d", 536 updown, hours, minutes); 537 return (resbuf); 538 } 539 #endif 540