| 1 | #ifndef lint |
| 2 | static char sccsid[] = "@(#)rwhod.c 4.28 (Berkeley) 85/02/25"; |
| 3 | #endif |
| 4 | |
| 5 | #include <sys/types.h> |
| 6 | #include <sys/socket.h> |
| 7 | #include <sys/stat.h> |
| 8 | #include <sys/ioctl.h> |
| 9 | #include <sys/file.h> |
| 10 | |
| 11 | #include <net/if.h> |
| 12 | #include <netinet/in.h> |
| 13 | |
| 14 | #include <nlist.h> |
| 15 | #include <stdio.h> |
| 16 | #include <signal.h> |
| 17 | #include <errno.h> |
| 18 | #include <utmp.h> |
| 19 | #include <ctype.h> |
| 20 | #include <netdb.h> |
| 21 | #include <syslog.h> |
| 22 | #include "rwhod.h" |
| 23 | |
| 24 | /* |
| 25 | * Alarm interval. Don't forget to change the down time check in ruptime |
| 26 | * if this is changed. |
| 27 | */ |
| 28 | #define AL_INTERVAL (3 * 60) |
| 29 | #define MAXTTYS 256 /* Max # of utmp entries examined */ |
| 30 | |
| 31 | struct sockaddr_in sin = { AF_INET }; |
| 32 | |
| 33 | extern errno; |
| 34 | |
| 35 | char myname[32]; |
| 36 | |
| 37 | struct nlist nl[] = { |
| 38 | #define NL_AVENRUN 0 |
| 39 | { "_avenrun" }, |
| 40 | #define NL_BOOTTIME 1 |
| 41 | { "_boottime" }, |
| 42 | 0 |
| 43 | }; |
| 44 | |
| 45 | /* |
| 46 | * We communicate with each neighbor in |
| 47 | * a list constructed at the time we're |
| 48 | * started up. Neighbors are currently |
| 49 | * directly connected via a hardware interface. |
| 50 | */ |
| 51 | struct neighbor { |
| 52 | struct neighbor *n_next; |
| 53 | char *n_name; /* interface name */ |
| 54 | char *n_addr; /* who to send to */ |
| 55 | int n_addrlen; /* size of address */ |
| 56 | int n_flags; /* should forward?, interface flags */ |
| 57 | }; |
| 58 | |
| 59 | struct neighbor *neighbors; |
| 60 | struct whod mywd; |
| 61 | struct servent *sp; |
| 62 | int s, utmpf, kmemf = -1; |
| 63 | |
| 64 | #define WHDRSIZE (sizeof (mywd) - sizeof (mywd.wd_we)) |
| 65 | #define RWHODIR "/usr/spool/rwho" |
| 66 | |
| 67 | int onalrm(); |
| 68 | char *strcpy(), *sprintf(), *malloc(); |
| 69 | long lseek(); |
| 70 | int getkmem(); |
| 71 | struct in_addr inet_makeaddr(); |
| 72 | |
| 73 | main() |
| 74 | { |
| 75 | struct sockaddr_in from; |
| 76 | char path[64]; |
| 77 | int addr, on = 1; |
| 78 | struct hostent *hp; |
| 79 | |
| 80 | if (getuid()) { |
| 81 | fprintf(stderr, "rwhod: not super user\n"); |
| 82 | exit(1); |
| 83 | } |
| 84 | sp = getservbyname("who", "udp"); |
| 85 | if (sp == 0) { |
| 86 | fprintf(stderr, "rwhod: udp/who: unknown service\n"); |
| 87 | exit(1); |
| 88 | } |
| 89 | #ifndef DEBUG |
| 90 | if (fork()) |
| 91 | exit(0); |
| 92 | { int s; |
| 93 | for (s = 0; s < 10; s++) |
| 94 | (void) close(s); |
| 95 | (void) open("/", 0); |
| 96 | (void) dup2(0, 1); |
| 97 | (void) dup2(0, 2); |
| 98 | s = open("/dev/tty", 2); |
| 99 | if (s >= 0) { |
| 100 | ioctl(s, TIOCNOTTY, 0); |
| 101 | (void) close(s); |
| 102 | } |
| 103 | } |
| 104 | #endif |
| 105 | (void) chdir("/dev"); |
| 106 | (void) signal(SIGHUP, getkmem); |
| 107 | openlog("rwhod", LOG_PID, 0); |
| 108 | /* |
| 109 | * Establish host name as returned by system. |
| 110 | */ |
| 111 | if (gethostname(myname, sizeof (myname) - 1) < 0) { |
| 112 | syslog(LOG_ERR, "gethostname: %m"); |
| 113 | exit(1); |
| 114 | } |
| 115 | strncpy(mywd.wd_hostname, myname, sizeof (myname) - 1); |
| 116 | utmpf = open("/etc/utmp", O_RDONLY); |
| 117 | if (utmpf < 0) { |
| 118 | (void) close(creat("/etc/utmp", 0644)); |
| 119 | utmpf = open("/etc/utmp", O_RDONLY); |
| 120 | } |
| 121 | if (utmpf < 0) { |
| 122 | syslog(LOG_ERR, "/etc/utmp: %m"); |
| 123 | exit(1); |
| 124 | } |
| 125 | getkmem(); |
| 126 | if ((s = socket(AF_INET, SOCK_DGRAM, 0)) < 0) { |
| 127 | syslog(LOG_ERR, "socket: %m"); |
| 128 | exit(1); |
| 129 | } |
| 130 | if (setsockopt(s, SOL_SOCKET, SO_BROADCAST, &on, sizeof (on)) < 0) { |
| 131 | syslog(LOG_ERR, "setsockopt SO_BROADCAST: %m"); |
| 132 | exit(1); |
| 133 | } |
| 134 | hp = gethostbyname(myname); |
| 135 | if (hp == NULL) { |
| 136 | syslog(LOG_ERR, "%s: don't know my own name", myname); |
| 137 | exit(1); |
| 138 | } |
| 139 | sin.sin_family = hp->h_addrtype; |
| 140 | sin.sin_port = sp->s_port; |
| 141 | if (bind(s, &sin, sizeof (sin)) < 0) { |
| 142 | syslog(LOG_ERR, "bind: %m"); |
| 143 | exit(1); |
| 144 | } |
| 145 | if (!configure(s)) |
| 146 | exit(1); |
| 147 | signal(SIGALRM, onalrm); |
| 148 | onalrm(); |
| 149 | for (;;) { |
| 150 | struct whod wd; |
| 151 | int cc, whod, len = sizeof (from); |
| 152 | |
| 153 | cc = recvfrom(s, (char *)&wd, sizeof (struct whod), 0, |
| 154 | &from, &len); |
| 155 | if (cc <= 0) { |
| 156 | if (cc < 0 && errno != EINTR) |
| 157 | syslog(LOG_WARNING, "recv: %m"); |
| 158 | continue; |
| 159 | } |
| 160 | if (from.sin_port != sp->s_port) { |
| 161 | syslog(LOG_WARNING, "%d: bad from port", |
| 162 | ntohs(from.sin_port)); |
| 163 | continue; |
| 164 | } |
| 165 | #ifdef notdef |
| 166 | if (gethostbyname(wd.wd_hostname) == 0) { |
| 167 | syslog(LOG_WARNING, "%s: unknown host", |
| 168 | wd.wd_hostname); |
| 169 | continue; |
| 170 | } |
| 171 | #endif |
| 172 | if (wd.wd_vers != WHODVERSION) |
| 173 | continue; |
| 174 | if (wd.wd_type != WHODTYPE_STATUS) |
| 175 | continue; |
| 176 | if (!verify(wd.wd_hostname)) { |
| 177 | syslog(LOG_WARNING, "malformed host name from %x", |
| 178 | from.sin_addr); |
| 179 | continue; |
| 180 | } |
| 181 | (void) sprintf(path, "%s/whod.%s", RWHODIR, wd.wd_hostname); |
| 182 | whod = creat(path, 0666); |
| 183 | if (whod < 0) { |
| 184 | syslog(LOG_WARNING, "%s: %m", path); |
| 185 | continue; |
| 186 | } |
| 187 | #if vax || pdp11 |
| 188 | { |
| 189 | int i, n = (cc - WHDRSIZE)/sizeof(struct whoent); |
| 190 | struct whoent *we; |
| 191 | |
| 192 | /* undo header byte swapping before writing to file */ |
| 193 | wd.wd_sendtime = ntohl(wd.wd_sendtime); |
| 194 | for (i = 0; i < 3; i++) |
| 195 | wd.wd_loadav[i] = ntohl(wd.wd_loadav[i]); |
| 196 | wd.wd_boottime = ntohl(wd.wd_boottime); |
| 197 | we = wd.wd_we; |
| 198 | for (i = 0; i < n; i++) { |
| 199 | we->we_idle = ntohl(we->we_idle); |
| 200 | we->we_utmp.out_time = |
| 201 | ntohl(we->we_utmp.out_time); |
| 202 | we++; |
| 203 | } |
| 204 | } |
| 205 | #endif |
| 206 | (void) time(&wd.wd_recvtime); |
| 207 | (void) write(whod, (char *)&wd, cc); |
| 208 | (void) close(whod); |
| 209 | } |
| 210 | } |
| 211 | |
| 212 | /* |
| 213 | * Check out host name for unprintables |
| 214 | * and other funnies before allowing a file |
| 215 | * to be created. Sorry, but blanks aren't allowed. |
| 216 | */ |
| 217 | verify(name) |
| 218 | register char *name; |
| 219 | { |
| 220 | register int size = 0; |
| 221 | |
| 222 | while (*name) { |
| 223 | if (!isascii(*name) || !(isalnum(*name) || ispunct(*name))) |
| 224 | return (0); |
| 225 | name++, size++; |
| 226 | } |
| 227 | return (size > 0); |
| 228 | } |
| 229 | |
| 230 | int utmptime; |
| 231 | int utmpent; |
| 232 | struct utmp utmp[MAXTTYS]; |
| 233 | int alarmcount; |
| 234 | |
| 235 | onalrm() |
| 236 | { |
| 237 | register int i; |
| 238 | struct stat stb; |
| 239 | register struct whoent *we = mywd.wd_we, *wlast; |
| 240 | int cc; |
| 241 | double avenrun[3]; |
| 242 | time_t now = time(0); |
| 243 | register struct neighbor *np; |
| 244 | |
| 245 | if (alarmcount % 10 == 0) |
| 246 | getkmem(); |
| 247 | alarmcount++; |
| 248 | (void) fstat(utmpf, &stb); |
| 249 | if (stb.st_mtime != utmptime) { |
| 250 | utmptime = stb.st_mtime; |
| 251 | (void) lseek(utmpf, (long)0, L_SET); |
| 252 | cc = read(utmpf, (char *)utmp, sizeof (utmp)); |
| 253 | if (cc < 0) { |
| 254 | perror("/etc/utmp"); |
| 255 | goto done; |
| 256 | } |
| 257 | wlast = &mywd.wd_we[1024 / sizeof (struct whoent) - 1]; |
| 258 | utmpent = cc / sizeof (struct utmp); |
| 259 | for (i = 0; i < utmpent; i++) |
| 260 | if (utmp[i].ut_name[0]) { |
| 261 | bcopy(utmp[i].ut_line, we->we_utmp.out_line, |
| 262 | sizeof (utmp[i].ut_line)); |
| 263 | bcopy(utmp[i].ut_name, we->we_utmp.out_name, |
| 264 | sizeof (utmp[i].ut_name)); |
| 265 | we->we_utmp.out_time = htonl(utmp[i].ut_time); |
| 266 | if (we >= wlast) |
| 267 | break; |
| 268 | we++; |
| 269 | } |
| 270 | utmpent = we - mywd.wd_we; |
| 271 | } |
| 272 | we = mywd.wd_we; |
| 273 | for (i = 0; i < utmpent; i++) { |
| 274 | if (stat(we->we_utmp.out_line, &stb) >= 0) |
| 275 | we->we_idle = htonl(now - stb.st_atime); |
| 276 | we++; |
| 277 | } |
| 278 | (void) lseek(kmemf, (long)nl[NL_AVENRUN].n_value, L_SET); |
| 279 | (void) read(kmemf, (char *)avenrun, sizeof (avenrun)); |
| 280 | for (i = 0; i < 3; i++) |
| 281 | mywd.wd_loadav[i] = htonl((u_long)(avenrun[i] * 100)); |
| 282 | cc = (char *)we - (char *)&mywd; |
| 283 | mywd.wd_sendtime = htonl(time(0)); |
| 284 | mywd.wd_vers = WHODVERSION; |
| 285 | mywd.wd_type = WHODTYPE_STATUS; |
| 286 | for (np = neighbors; np != NULL; np = np->n_next) |
| 287 | (void) sendto(s, (char *)&mywd, cc, 0, |
| 288 | np->n_addr, np->n_addrlen); |
| 289 | done: |
| 290 | (void) alarm(AL_INTERVAL); |
| 291 | } |
| 292 | |
| 293 | getkmem() |
| 294 | { |
| 295 | struct nlist *nlp; |
| 296 | static ino_t vmunixino; |
| 297 | static time_t vmunixctime; |
| 298 | struct stat sb; |
| 299 | |
| 300 | if (stat("/vmunix", &sb) < 0) { |
| 301 | if (vmunixctime) |
| 302 | return; |
| 303 | } else { |
| 304 | if (sb.st_ctime == vmunixctime && sb.st_ino == vmunixino) |
| 305 | return; |
| 306 | vmunixctime = sb.st_ctime; |
| 307 | vmunixino= sb.st_ino; |
| 308 | } |
| 309 | if (kmemf >= 0) |
| 310 | (void) close(kmemf); |
| 311 | loop: |
| 312 | if (nlist("/vmunix", nl)) { |
| 313 | syslog(LOG_WARNING, "/vmunix namelist botch"); |
| 314 | sleep(300); |
| 315 | goto loop; |
| 316 | } |
| 317 | kmemf = open("/dev/kmem", O_RDONLY); |
| 318 | if (kmemf < 0) { |
| 319 | syslog(LOG_ERR, "/dev/kmem: %m"); |
| 320 | exit(1); |
| 321 | } |
| 322 | (void) lseek(kmemf, (long)nl[NL_BOOTTIME].n_value, L_SET); |
| 323 | (void) read(kmemf, (char *)&mywd.wd_boottime, |
| 324 | sizeof (mywd.wd_boottime)); |
| 325 | mywd.wd_boottime = htonl(mywd.wd_boottime); |
| 326 | } |
| 327 | |
| 328 | /* |
| 329 | * Figure out device configuration and select |
| 330 | * networks which deserve status information. |
| 331 | */ |
| 332 | configure(s) |
| 333 | int s; |
| 334 | { |
| 335 | char buf[BUFSIZ]; |
| 336 | struct ifconf ifc; |
| 337 | struct ifreq ifreq, *ifr; |
| 338 | struct sockaddr_in *sin; |
| 339 | register struct neighbor *np; |
| 340 | int n; |
| 341 | |
| 342 | ifc.ifc_len = sizeof (buf); |
| 343 | ifc.ifc_buf = buf; |
| 344 | if (ioctl(s, SIOCGIFCONF, (char *)&ifc) < 0) { |
| 345 | syslog(LOG_ERR, "ioctl (get interface configuration)"); |
| 346 | return (0); |
| 347 | } |
| 348 | ifr = ifc.ifc_req; |
| 349 | for (n = ifc.ifc_len / sizeof (struct ifreq); n > 0; n--, ifr++) { |
| 350 | for (np = neighbors; np != NULL; np = np->n_next) |
| 351 | if (np->n_name && |
| 352 | strcmp(ifr->ifr_name, np->n_name) == 0) |
| 353 | break; |
| 354 | if (np != NULL) |
| 355 | continue; |
| 356 | ifreq = *ifr; |
| 357 | np = (struct neighbor *)malloc(sizeof (*np)); |
| 358 | if (np == NULL) |
| 359 | continue; |
| 360 | np->n_name = malloc(strlen(ifr->ifr_name) + 1); |
| 361 | if (np->n_name == NULL) { |
| 362 | free((char *)np); |
| 363 | continue; |
| 364 | } |
| 365 | strcpy(np->n_name, ifr->ifr_name); |
| 366 | np->n_addrlen = sizeof (ifr->ifr_addr); |
| 367 | np->n_addr = malloc(np->n_addrlen); |
| 368 | if (np->n_addr == NULL) { |
| 369 | free(np->n_name); |
| 370 | free((char *)np); |
| 371 | continue; |
| 372 | } |
| 373 | bcopy((char *)&ifr->ifr_addr, np->n_addr, np->n_addrlen); |
| 374 | if (ioctl(s, SIOCGIFFLAGS, (char *)&ifreq) < 0) { |
| 375 | syslog(LOG_ERR, "ioctl (get interface flags)"); |
| 376 | free((char *)np); |
| 377 | continue; |
| 378 | } |
| 379 | if ((ifreq.ifr_flags & (IFF_BROADCAST|IFF_POINTOPOINT)) == 0) { |
| 380 | free((char *)np); |
| 381 | continue; |
| 382 | } |
| 383 | np->n_flags = ifreq.ifr_flags; |
| 384 | if (np->n_flags & IFF_POINTOPOINT) { |
| 385 | if (ioctl(s, SIOCGIFDSTADDR, (char *)&ifreq) < 0) { |
| 386 | syslog(LOG_ERR, "ioctl (get dstaddr)"); |
| 387 | free((char *)np); |
| 388 | continue; |
| 389 | } |
| 390 | /* we assume addresses are all the same size */ |
| 391 | bcopy((char *)&ifreq.ifr_dstaddr, |
| 392 | np->n_addr, np->n_addrlen); |
| 393 | } |
| 394 | if (np->n_flags & IFF_BROADCAST) { |
| 395 | /* we assume addresses are all the same size */ |
| 396 | sin = (struct sockaddr_in *)np->n_addr; |
| 397 | sin->sin_addr = inet_makeaddr((np->n_flags & IFF_LOCAL)? |
| 398 | inet_subnetof(sin->sin_addr) : |
| 399 | inet_netof(sin->sin_addr), |
| 400 | INADDR_ANY); |
| 401 | } |
| 402 | /* gag, wish we could get rid of Internet dependencies */ |
| 403 | sin = (struct sockaddr_in *)np->n_addr; |
| 404 | sin->sin_port = sp->s_port; |
| 405 | np->n_next = neighbors; |
| 406 | neighbors = np; |
| 407 | } |
| 408 | return (1); |
| 409 | } |
| 410 | |
| 411 | /* |
| 412 | * Return the possible subnetwork number from an internet address. |
| 413 | * If the address is of the form of a subnet address (most significant |
| 414 | * bit of the host part is set), believe the subnet exists. |
| 415 | * Otherwise, return the network number. Any subnet number is only valid |
| 416 | * if this is a ``local'' net. |
| 417 | */ |
| 418 | inet_subnetof(in) |
| 419 | struct in_addr in; |
| 420 | { |
| 421 | register u_long i = ntohl(in.s_addr); |
| 422 | |
| 423 | if (IN_CLASSA(i)) { |
| 424 | if (IN_SUBNETA(i)) |
| 425 | return ((i & IN_CLASSA_SUBNET) >> IN_CLASSA_SUBNSHIFT); |
| 426 | else |
| 427 | return ((i & IN_CLASSA_NET) >> IN_CLASSA_NSHIFT); |
| 428 | } else if (IN_CLASSB(i)) { |
| 429 | if (IN_SUBNETB(i)) |
| 430 | return ((i & IN_CLASSB_SUBNET) >> IN_CLASSB_SUBNSHIFT); |
| 431 | else |
| 432 | return ((i & IN_CLASSB_NET) >> IN_CLASSB_NSHIFT); |
| 433 | } else |
| 434 | return ((i & IN_CLASSC_NET) >> IN_CLASSC_NSHIFT); |
| 435 | } |
| 436 | |
| 437 | #ifdef DEBUG |
| 438 | sendto(s, buf, cc, flags, to, tolen) |
| 439 | int s; |
| 440 | char *buf; |
| 441 | int cc, flags; |
| 442 | char *to; |
| 443 | int tolen; |
| 444 | { |
| 445 | register struct whod *w = (struct whod *)buf; |
| 446 | register struct whoent *we; |
| 447 | struct sockaddr_in *sin = (struct sockaddr_in *)to; |
| 448 | char *interval(); |
| 449 | |
| 450 | printf("sendto %x.%d\n", ntohl(sin->sin_addr), ntohs(sin->sin_port)); |
| 451 | printf("hostname %s %s\n", w->wd_hostname, |
| 452 | interval(ntohl(w->wd_sendtime) - ntohl(w->wd_boottime), " up")); |
| 453 | printf("load %4.2f, %4.2f, %4.2f\n", |
| 454 | ntohl(w->wd_loadav[0]) / 100.0, ntohl(w->wd_loadav[1]) / 100.0, |
| 455 | ntohl(w->wd_loadav[2]) / 100.0); |
| 456 | cc -= WHDRSIZE; |
| 457 | for (we = w->wd_we, cc /= sizeof (struct whoent); cc > 0; cc--, we++) { |
| 458 | time_t t = ntohl(we->we_utmp.out_time); |
| 459 | printf("%-8.8s %s:%s %.12s", |
| 460 | we->we_utmp.out_name, |
| 461 | w->wd_hostname, we->we_utmp.out_line, |
| 462 | ctime(&t)+4); |
| 463 | we->we_idle = ntohl(we->we_idle) / 60; |
| 464 | if (we->we_idle) { |
| 465 | if (we->we_idle >= 100*60) |
| 466 | we->we_idle = 100*60 - 1; |
| 467 | if (we->we_idle >= 60) |
| 468 | printf(" %2d", we->we_idle / 60); |
| 469 | else |
| 470 | printf(" "); |
| 471 | printf(":%02d", we->we_idle % 60); |
| 472 | } |
| 473 | printf("\n"); |
| 474 | } |
| 475 | } |
| 476 | |
| 477 | char * |
| 478 | interval(time, updown) |
| 479 | int time; |
| 480 | char *updown; |
| 481 | { |
| 482 | static char resbuf[32]; |
| 483 | int days, hours, minutes; |
| 484 | |
| 485 | if (time < 0 || time > 3*30*24*60*60) { |
| 486 | (void) sprintf(resbuf, " %s ??:??", updown); |
| 487 | return (resbuf); |
| 488 | } |
| 489 | minutes = (time + 59) / 60; /* round to minutes */ |
| 490 | hours = minutes / 60; minutes %= 60; |
| 491 | days = hours / 24; hours %= 24; |
| 492 | if (days) |
| 493 | (void) sprintf(resbuf, "%s %2d+%02d:%02d", |
| 494 | updown, days, hours, minutes); |
| 495 | else |
| 496 | (void) sprintf(resbuf, "%s %2d:%02d", |
| 497 | updown, hours, minutes); |
| 498 | return (resbuf); |
| 499 | } |
| 500 | #endif |