Lorenzo Colitti | 313379e | 2013-07-11 01:07:11 +0900 | [diff] [blame] | 1 | /* |
| 2 | * Rdisc (this program) was developed by Sun Microsystems, Inc. and is |
| 3 | * provided for unrestricted use provided that this legend is included on |
| 4 | * all tape media and as a part of the software program in whole or part. |
| 5 | * Users may copy or modify Rdisc without charge, and they may freely |
| 6 | * distribute it. |
| 7 | * |
| 8 | * RDISC IS PROVIDED AS IS WITH NO WARRANTIES OF ANY KIND INCLUDING THE |
| 9 | * WARRANTIES OF DESIGN, MERCHANTIBILITY AND FITNESS FOR A PARTICULAR |
| 10 | * PURPOSE, OR ARISING FROM A COURSE OF DEALING, USAGE OR TRADE PRACTICE. |
| 11 | * |
| 12 | * Rdisc is provided with no support and without any obligation on the |
| 13 | * part of Sun Microsystems, Inc. to assist in its use, correction, |
| 14 | * modification or enhancement. |
| 15 | * |
| 16 | * SUN MICROSYSTEMS, INC. SHALL HAVE NO LIABILITY WITH RESPECT TO THE |
| 17 | * INFRINGEMENT OF COPYRIGHTS, TRADE SECRETS OR ANY PATENTS BY RDISC |
| 18 | * OR ANY PART THEREOF. |
| 19 | * |
| 20 | * In no event will Sun Microsystems, Inc. be liable for any lost revenue |
| 21 | * or profits or other special, indirect and consequential damages, even if |
| 22 | * Sun has been advised of the possibility of such damages. |
| 23 | * |
| 24 | * Sun Microsystems, Inc. |
| 25 | * 2550 Garcia Avenue |
| 26 | * Mountain View, California 94043 |
| 27 | */ |
| 28 | #include <stdio.h> |
| 29 | #include <errno.h> |
| 30 | #include <signal.h> |
| 31 | #include <unistd.h> |
| 32 | #include <stdlib.h> |
| 33 | #include <sys/types.h> |
| 34 | #include <sys/time.h> |
| 35 | /* Do not use "improved" glibc version! */ |
| 36 | #include <linux/limits.h> |
| 37 | |
| 38 | #include <sys/param.h> |
| 39 | #include <sys/socket.h> |
| 40 | #include <sys/file.h> |
| 41 | #include <malloc.h> |
| 42 | |
| 43 | #include <sys/ioctl.h> |
| 44 | #include <linux/if.h> |
| 45 | #include <linux/route.h> |
| 46 | |
| 47 | #include <netinet/in.h> |
| 48 | #include <netinet/ip.h> |
| 49 | #include <netinet/ip_icmp.h> |
| 50 | |
| 51 | /* |
| 52 | * The next include contains all defs and structures for multicast |
| 53 | * that are not in SunOS 4.1.x. On a SunOS 4.1.x system none of this code |
| 54 | * is ever used because it does not support multicast |
| 55 | * Fraser Gardiner - Sun Microsystems Australia |
| 56 | */ |
| 57 | |
| 58 | #include <netdb.h> |
| 59 | #include <arpa/inet.h> |
| 60 | |
| 61 | #include <string.h> |
| 62 | #include <syslog.h> |
| 63 | |
| 64 | #include "SNAPSHOT.h" |
| 65 | |
| 66 | struct interface |
| 67 | { |
| 68 | struct in_addr address; /* Used to identify the interface */ |
| 69 | struct in_addr localaddr; /* Actual address if the interface */ |
| 70 | int preference; |
| 71 | int flags; |
| 72 | struct in_addr bcastaddr; |
| 73 | struct in_addr remoteaddr; |
| 74 | struct in_addr netmask; |
| 75 | int ifindex; |
| 76 | char name[IFNAMSIZ]; |
| 77 | }; |
| 78 | |
| 79 | /* |
| 80 | * TBD |
| 81 | * Use 255.255.255.255 for broadcasts - not the interface broadcast |
| 82 | * address. |
| 83 | */ |
| 84 | |
| 85 | #define ALLIGN(ptr) (ptr) |
| 86 | |
| 87 | static int join(int sock, struct sockaddr_in *sin); |
| 88 | static void solicitor(struct sockaddr_in *); |
| 89 | #ifdef RDISC_SERVER |
| 90 | static void advertise(struct sockaddr_in *, int lft); |
| 91 | #endif |
| 92 | static char *pr_name(struct in_addr addr); |
| 93 | static void pr_pack(char *buf, int cc, struct sockaddr_in *from); |
| 94 | static void age_table(int time); |
| 95 | static void record_router(struct in_addr router, int preference, int ttl); |
| 96 | static void add_route(struct in_addr addr); |
| 97 | static void del_route(struct in_addr addr); |
| 98 | static void rtioctl(struct in_addr addr, int op); |
| 99 | static int support_multicast(void); |
| 100 | static int sendbcast(int s, char *packet, int packetlen); |
| 101 | static int sendmcast(int s, char *packet, int packetlen, struct sockaddr_in *); |
| 102 | static int sendbcastif(int s, char *packet, int packetlen, struct interface *ifp); |
| 103 | static int sendmcastif(int s, char *packet, int packetlen, struct sockaddr_in *sin, struct interface *ifp); |
| 104 | static int is_directly_connected(struct in_addr in); |
| 105 | static void initlog(void); |
| 106 | static void discard_table(void); |
| 107 | static void init(void); |
| 108 | |
| 109 | #define ICMP_ROUTER_ADVERTISEMENT 9 |
| 110 | #define ICMP_ROUTER_SOLICITATION 10 |
| 111 | |
| 112 | #define ALL_HOSTS_ADDRESS "224.0.0.1" |
| 113 | #define ALL_ROUTERS_ADDRESS "224.0.0.2" |
| 114 | |
| 115 | #define MAXIFS 32 |
| 116 | |
| 117 | #if !defined(__GLIBC__) || __GLIBC__ < 2 |
| 118 | /* For router advertisement */ |
| 119 | struct icmp_ra |
| 120 | { |
| 121 | u_char icmp_type; /* type of message, see below */ |
| 122 | u_char icmp_code; /* type sub code */ |
| 123 | u_short icmp_cksum; /* ones complement cksum of struct */ |
| 124 | u_char icmp_num_addrs; |
| 125 | u_char icmp_wpa; /* Words per address */ |
| 126 | short icmp_lifetime; |
| 127 | }; |
| 128 | |
| 129 | struct icmp_ra_addr |
| 130 | { |
| 131 | __u32 ira_addr; |
| 132 | __u32 ira_preference; |
| 133 | }; |
| 134 | #else |
| 135 | #define icmp_ra icmp |
| 136 | #endif |
| 137 | |
| 138 | /* Router constants */ |
| 139 | #define MAX_INITIAL_ADVERT_INTERVAL 16 |
| 140 | #define MAX_INITIAL_ADVERTISEMENTS 3 |
| 141 | #define MAX_RESPONSE_DELAY 2 /* Not used */ |
| 142 | |
| 143 | /* Host constants */ |
| 144 | #define MAX_SOLICITATIONS 3 |
| 145 | #define SOLICITATION_INTERVAL 3 |
| 146 | #define MAX_SOLICITATION_DELAY 1 /* Not used */ |
| 147 | |
| 148 | #define INELIGIBLE_PREF 0x80000000 /* Maximum negative */ |
| 149 | |
| 150 | #define MAX_ADV_INT 600 |
| 151 | |
| 152 | /* Statics */ |
| 153 | static int num_interfaces; |
| 154 | |
| 155 | static struct interface *interfaces; |
| 156 | static int interfaces_size; /* Number of elements in interfaces */ |
| 157 | |
| 158 | |
| 159 | #define MAXPACKET 4096 /* max packet size */ |
| 160 | |
| 161 | /* fraser */ |
| 162 | int debugfile; |
| 163 | |
| 164 | const char usage[] = |
| 165 | "Usage: rdisc [-b] [-d] [-s] [-v] [-f] [-a] [-V] [send_address] [receive_address]\n" |
| 166 | #ifdef RDISC_SERVER |
| 167 | " rdisc -r [-b] [-d] [-s] [-v] [-f] [-a] [-V] [-p <preference>] [-T <secs>]\n" |
| 168 | " [send_address] [receive_address]\n" |
| 169 | #endif |
| 170 | ; |
| 171 | |
| 172 | |
| 173 | int s; /* Socket file descriptor */ |
| 174 | struct sockaddr_in whereto;/* Address to send to */ |
| 175 | |
| 176 | /* Common variables */ |
| 177 | int verbose = 0; |
| 178 | int debug = 0; |
| 179 | int trace = 0; |
| 180 | int solicit = 0; |
| 181 | int ntransmitted = 0; |
| 182 | int nreceived = 0; |
| 183 | int forever = 0; /* Never give up on host. If 0 defer fork until |
| 184 | * first response. |
| 185 | */ |
| 186 | |
| 187 | #ifdef RDISC_SERVER |
| 188 | /* Router variables */ |
| 189 | int responder; |
| 190 | int max_adv_int = MAX_ADV_INT; |
| 191 | int min_adv_int; |
| 192 | int lifetime; |
| 193 | int initial_advert_interval = MAX_INITIAL_ADVERT_INTERVAL; |
| 194 | int initial_advertisements = MAX_INITIAL_ADVERTISEMENTS; |
| 195 | int preference = 0; /* Setable with -p option */ |
| 196 | #endif |
| 197 | |
| 198 | /* Host variables */ |
| 199 | int max_solicitations = MAX_SOLICITATIONS; |
| 200 | unsigned int solicitation_interval = SOLICITATION_INTERVAL; |
| 201 | int best_preference = 1; /* Set to record only the router(s) with the |
| 202 | best preference in the kernel. Not set |
| 203 | puts all routes in the kernel. */ |
| 204 | |
| 205 | |
| 206 | static void graceful_finish(void); |
| 207 | static void finish(void); |
| 208 | static void timer(void); |
| 209 | static void initifs(void); |
| 210 | static u_short in_cksum(u_short *addr, int len); |
| 211 | |
| 212 | static int logging = 0; |
| 213 | |
| 214 | #define logerr(fmt...) ({ if (logging) syslog(LOG_ERR, fmt); \ |
| 215 | else fprintf(stderr, fmt); }) |
| 216 | #define logtrace(fmt...) ({ if (logging) syslog(LOG_INFO, fmt); \ |
| 217 | else fprintf(stderr, fmt); }) |
| 218 | #define logdebug(fmt...) ({ if (logging) syslog(LOG_DEBUG, fmt); \ |
| 219 | else fprintf(stderr, fmt); }) |
| 220 | static void logperror(char *str); |
| 221 | |
| 222 | static __inline__ int isbroadcast(struct sockaddr_in *sin) |
| 223 | { |
| 224 | return (sin->sin_addr.s_addr == INADDR_BROADCAST); |
| 225 | } |
| 226 | |
| 227 | static __inline__ int ismulticast(struct sockaddr_in *sin) |
| 228 | { |
| 229 | return IN_CLASSD(ntohl(sin->sin_addr.s_addr)); |
| 230 | } |
| 231 | |
| 232 | static void prusage(void) |
| 233 | { |
| 234 | fputs(usage, stderr); |
| 235 | exit(1); |
| 236 | } |
| 237 | |
| 238 | void do_fork(void) |
| 239 | { |
| 240 | int t; |
| 241 | pid_t pid; |
| 242 | long open_max; |
| 243 | |
| 244 | if (trace) |
| 245 | return; |
| 246 | if ((open_max = sysconf(_SC_OPEN_MAX)) == -1) { |
| 247 | if (errno == 0) { |
| 248 | (void) fprintf(stderr, "OPEN_MAX is not supported\n"); |
| 249 | } |
| 250 | else { |
| 251 | (void) fprintf(stderr, "sysconf() error\n"); |
| 252 | } |
| 253 | exit(1); |
| 254 | } |
| 255 | |
| 256 | |
| 257 | if ((pid=fork()) != 0) |
| 258 | exit(0); |
| 259 | |
| 260 | for (t = 0; t < open_max; t++) |
| 261 | if (t != s) |
| 262 | close(t); |
| 263 | |
| 264 | setsid(); |
| 265 | initlog(); |
| 266 | } |
| 267 | |
| 268 | void signal_setup(int signo, void (*handler)(void)) |
| 269 | { |
| 270 | struct sigaction sa; |
| 271 | |
| 272 | memset(&sa, 0, sizeof(sa)); |
| 273 | |
| 274 | sa.sa_handler = (void (*)(int))handler; |
| 275 | #ifdef SA_INTERRUPT |
| 276 | sa.sa_flags = SA_INTERRUPT; |
| 277 | #endif |
| 278 | sigaction(signo, &sa, NULL); |
| 279 | } |
| 280 | |
| 281 | /* |
| 282 | * M A I N |
| 283 | */ |
| 284 | char *sendaddress, *recvaddress; |
| 285 | |
| 286 | int main(int argc, char **argv) |
| 287 | { |
| 288 | struct sockaddr_in from; |
| 289 | char **av = argv; |
| 290 | struct sockaddr_in *to = &whereto; |
| 291 | struct sockaddr_in joinaddr; |
| 292 | sigset_t sset, sset_empty; |
| 293 | #ifdef RDISC_SERVER |
| 294 | int val; |
| 295 | |
| 296 | min_adv_int =( max_adv_int * 3 / 4); |
| 297 | lifetime = (3*max_adv_int); |
| 298 | #endif |
| 299 | |
| 300 | argc--, av++; |
| 301 | while (argc > 0 && *av[0] == '-') { |
| 302 | while (*++av[0]) { |
| 303 | switch (*av[0]) { |
| 304 | case 'd': |
| 305 | debug = 1; |
| 306 | break; |
| 307 | case 't': |
| 308 | trace = 1; |
| 309 | break; |
| 310 | case 'v': |
| 311 | verbose++; |
| 312 | break; |
| 313 | case 's': |
| 314 | solicit = 1; |
| 315 | break; |
| 316 | #ifdef RDISC_SERVER |
| 317 | case 'r': |
| 318 | responder = 1; |
| 319 | break; |
| 320 | #endif |
| 321 | case 'a': |
| 322 | best_preference = 0; |
| 323 | break; |
| 324 | case 'b': |
| 325 | best_preference = 1; |
| 326 | break; |
| 327 | case 'f': |
| 328 | forever = 1; |
| 329 | break; |
| 330 | case 'V': |
| 331 | printf("rdisc utility, iputils-%s\n", SNAPSHOT); |
| 332 | exit(0); |
| 333 | #ifdef RDISC_SERVER |
| 334 | case 'T': |
| 335 | argc--, av++; |
| 336 | if (argc != 0) { |
| 337 | val = strtol(av[0], (char **)NULL, 0); |
| 338 | if (val < 4 || val > 1800) { |
| 339 | (void) fprintf(stderr, |
| 340 | "Bad Max Advertizement Interval\n"); |
| 341 | exit(1); |
| 342 | } |
| 343 | max_adv_int = val; |
| 344 | min_adv_int =( max_adv_int * 3 / 4); |
| 345 | lifetime = (3*max_adv_int); |
| 346 | } else { |
| 347 | prusage(); |
| 348 | /* NOTREACHED*/ |
| 349 | } |
| 350 | goto next; |
| 351 | case 'p': |
| 352 | argc--, av++; |
| 353 | if (argc != 0) { |
| 354 | val = strtol(av[0], (char **)NULL, 0); |
| 355 | preference = val; |
| 356 | } else { |
| 357 | prusage(); |
| 358 | /* NOTREACHED*/ |
| 359 | } |
| 360 | goto next; |
| 361 | #endif |
| 362 | default: |
| 363 | prusage(); |
| 364 | /* NOTREACHED*/ |
| 365 | } |
| 366 | } |
| 367 | #ifdef RDISC_SERVER |
| 368 | next: |
| 369 | #endif |
| 370 | argc--, av++; |
| 371 | } |
| 372 | if( argc < 1) { |
| 373 | if (support_multicast()) { |
| 374 | sendaddress = ALL_ROUTERS_ADDRESS; |
| 375 | #ifdef RDISC_SERVER |
| 376 | if (responder) |
| 377 | sendaddress = ALL_HOSTS_ADDRESS; |
| 378 | #endif |
| 379 | } else |
| 380 | sendaddress = "255.255.255.255"; |
| 381 | } else { |
| 382 | sendaddress = av[0]; |
| 383 | argc--; |
| 384 | } |
| 385 | |
| 386 | if (argc < 1) { |
| 387 | if (support_multicast()) { |
| 388 | recvaddress = ALL_HOSTS_ADDRESS; |
| 389 | #ifdef RDISC_SERVER |
| 390 | if (responder) |
| 391 | recvaddress = ALL_ROUTERS_ADDRESS; |
| 392 | #endif |
| 393 | } else |
| 394 | recvaddress = "255.255.255.255"; |
| 395 | } else { |
| 396 | recvaddress = av[0]; |
| 397 | argc--; |
| 398 | } |
| 399 | if (argc != 0) { |
| 400 | (void) fprintf(stderr, "Extra parameters\n"); |
| 401 | prusage(); |
| 402 | /* NOTREACHED */ |
| 403 | } |
| 404 | |
| 405 | #ifdef RDISC_SERVER |
| 406 | if (solicit && responder) { |
| 407 | prusage(); |
| 408 | /* NOTREACHED */ |
| 409 | } |
| 410 | #endif |
| 411 | |
| 412 | if (!(solicit && !forever)) { |
| 413 | do_fork(); |
| 414 | /* |
| 415 | * Added the next line to stop forking a second time |
| 416 | * Fraser Gardiner - Sun Microsystems Australia |
| 417 | */ |
| 418 | forever = 1; |
| 419 | } |
| 420 | |
| 421 | memset( (char *)&whereto, 0, sizeof(struct sockaddr_in) ); |
| 422 | to->sin_family = AF_INET; |
| 423 | to->sin_addr.s_addr = inet_addr(sendaddress); |
| 424 | |
| 425 | memset( (char *)&joinaddr, 0, sizeof(struct sockaddr_in) ); |
| 426 | joinaddr.sin_family = AF_INET; |
| 427 | joinaddr.sin_addr.s_addr = inet_addr(recvaddress); |
| 428 | |
| 429 | #ifdef RDISC_SERVER |
| 430 | if (responder) |
| 431 | srandom((int)gethostid()); |
| 432 | #endif |
| 433 | |
| 434 | if ((s = socket(AF_INET, SOCK_RAW, IPPROTO_ICMP)) < 0) { |
| 435 | logperror("socket"); |
| 436 | exit(5); |
| 437 | } |
| 438 | |
| 439 | setlinebuf( stdout ); |
| 440 | |
| 441 | signal_setup(SIGINT, finish ); |
| 442 | signal_setup(SIGTERM, graceful_finish ); |
| 443 | signal_setup(SIGHUP, initifs ); |
| 444 | signal_setup(SIGALRM, timer ); |
| 445 | |
| 446 | sigemptyset(&sset); |
| 447 | sigemptyset(&sset_empty); |
| 448 | sigaddset(&sset, SIGALRM); |
| 449 | sigaddset(&sset, SIGHUP); |
| 450 | sigaddset(&sset, SIGTERM); |
| 451 | sigaddset(&sset, SIGINT); |
| 452 | |
| 453 | init(); |
| 454 | if (join(s, &joinaddr) < 0) { |
| 455 | logerr("Failed joining addresses\n"); |
| 456 | exit (2); |
| 457 | } |
| 458 | |
| 459 | timer(); /* start things going */ |
| 460 | |
| 461 | for (;;) { |
| 462 | u_char packet[MAXPACKET]; |
| 463 | int len = sizeof (packet); |
| 464 | socklen_t fromlen = sizeof (from); |
| 465 | int cc; |
| 466 | |
| 467 | cc=recvfrom(s, (char *)packet, len, 0, |
| 468 | (struct sockaddr *)&from, &fromlen); |
| 469 | if (cc<0) { |
| 470 | if (errno == EINTR) |
| 471 | continue; |
| 472 | logperror("recvfrom"); |
| 473 | continue; |
| 474 | } |
| 475 | |
| 476 | sigprocmask(SIG_SETMASK, &sset, NULL); |
| 477 | pr_pack( (char *)packet, cc, &from ); |
| 478 | sigprocmask(SIG_SETMASK, &sset_empty, NULL); |
| 479 | } |
| 480 | /*NOTREACHED*/ |
| 481 | } |
| 482 | |
| 483 | #define TIMER_INTERVAL 3 |
| 484 | #define GETIFCONF_TIMER 30 |
| 485 | |
| 486 | static int left_until_advertise; |
| 487 | |
| 488 | /* Called every TIMER_INTERVAL */ |
| 489 | void timer() |
| 490 | { |
| 491 | static int time; |
| 492 | static int left_until_getifconf; |
| 493 | static int left_until_solicit; |
| 494 | |
| 495 | |
| 496 | time += TIMER_INTERVAL; |
| 497 | |
| 498 | left_until_getifconf -= TIMER_INTERVAL; |
| 499 | left_until_advertise -= TIMER_INTERVAL; |
| 500 | left_until_solicit -= TIMER_INTERVAL; |
| 501 | |
| 502 | if (left_until_getifconf < 0) { |
| 503 | initifs(); |
| 504 | left_until_getifconf = GETIFCONF_TIMER; |
| 505 | } |
| 506 | #ifdef RDISC_SERVER |
| 507 | if (responder && left_until_advertise <= 0) { |
| 508 | ntransmitted++; |
| 509 | advertise(&whereto, lifetime); |
| 510 | if (ntransmitted < initial_advertisements) |
| 511 | left_until_advertise = initial_advert_interval; |
| 512 | else |
| 513 | left_until_advertise = min_adv_int + |
| 514 | ((max_adv_int - min_adv_int) * |
| 515 | (random() % 1000)/1000); |
| 516 | } else |
| 517 | #endif |
| 518 | if (solicit && left_until_solicit <= 0) { |
| 519 | ntransmitted++; |
| 520 | solicitor(&whereto); |
| 521 | if (ntransmitted < max_solicitations) |
| 522 | left_until_solicit = solicitation_interval; |
| 523 | else { |
| 524 | solicit = 0; |
| 525 | if (!forever && nreceived == 0) |
| 526 | exit(5); |
| 527 | } |
| 528 | } |
| 529 | age_table(TIMER_INTERVAL); |
| 530 | alarm(TIMER_INTERVAL); |
| 531 | } |
| 532 | |
| 533 | /* |
| 534 | * S O L I C I T O R |
| 535 | * |
| 536 | * Compose and transmit an ICMP ROUTER SOLICITATION REQUEST packet. |
| 537 | * The IP packet will be added on by the kernel. |
| 538 | */ |
| 539 | void |
| 540 | solicitor(struct sockaddr_in *sin) |
| 541 | { |
| 542 | static u_char outpack[MAXPACKET]; |
| 543 | struct icmphdr *icp = (struct icmphdr *) ALLIGN(outpack); |
| 544 | int packetlen, i; |
| 545 | |
| 546 | if (verbose) { |
| 547 | logtrace("Sending solicitation to %s\n", |
| 548 | pr_name(sin->sin_addr)); |
| 549 | } |
| 550 | icp->type = ICMP_ROUTER_SOLICITATION; |
| 551 | icp->code = 0; |
| 552 | icp->checksum = 0; |
| 553 | icp->un.gateway = 0; /* Reserved */ |
| 554 | packetlen = 8; |
| 555 | |
| 556 | /* Compute ICMP checksum here */ |
| 557 | icp->checksum = in_cksum( (u_short *)icp, packetlen ); |
| 558 | |
| 559 | if (isbroadcast(sin)) |
| 560 | i = sendbcast(s, (char *)outpack, packetlen); |
| 561 | else if (ismulticast(sin)) |
| 562 | i = sendmcast(s, (char *)outpack, packetlen, sin); |
| 563 | else |
| 564 | i = sendto( s, (char *)outpack, packetlen, 0, |
| 565 | (struct sockaddr *)sin, sizeof(struct sockaddr)); |
| 566 | |
| 567 | if( i < 0 || i != packetlen ) { |
| 568 | if( i<0 ) { |
| 569 | logperror("solicitor:sendto"); |
| 570 | } |
| 571 | logerr("wrote %s %d chars, ret=%d\n", |
| 572 | sendaddress, packetlen, i ); |
| 573 | } |
| 574 | } |
| 575 | |
| 576 | #ifdef RDISC_SERVER |
| 577 | /* |
| 578 | * A V E R T I S E |
| 579 | * |
| 580 | * Compose and transmit an ICMP ROUTER ADVERTISEMENT packet. |
| 581 | * The IP packet will be added on by the kernel. |
| 582 | */ |
| 583 | void |
| 584 | advertise(struct sockaddr_in *sin, int lft) |
| 585 | { |
| 586 | static u_char outpack[MAXPACKET]; |
| 587 | struct icmp_ra *rap = (struct icmp_ra *) ALLIGN(outpack); |
| 588 | struct icmp_ra_addr *ap; |
| 589 | int packetlen, i, cc; |
| 590 | |
| 591 | if (verbose) { |
| 592 | logtrace("Sending advertisement to %s\n", |
| 593 | pr_name(sin->sin_addr)); |
| 594 | } |
| 595 | |
| 596 | for (i = 0; i < num_interfaces; i++) { |
| 597 | rap->icmp_type = ICMP_ROUTER_ADVERTISEMENT; |
| 598 | rap->icmp_code = 0; |
| 599 | rap->icmp_cksum = 0; |
| 600 | rap->icmp_num_addrs = 0; |
| 601 | rap->icmp_wpa = 2; |
| 602 | rap->icmp_lifetime = htons(lft); |
| 603 | packetlen = 8; |
| 604 | |
| 605 | /* |
| 606 | * TODO handle multiple logical interfaces per |
| 607 | * physical interface. (increment with rap->icmp_wpa * 4 for |
| 608 | * each address.) |
| 609 | */ |
| 610 | ap = (struct icmp_ra_addr *)ALLIGN(outpack + ICMP_MINLEN); |
| 611 | ap->ira_addr = interfaces[i].localaddr.s_addr; |
| 612 | ap->ira_preference = htonl(interfaces[i].preference); |
| 613 | packetlen += rap->icmp_wpa * 4; |
| 614 | rap->icmp_num_addrs++; |
| 615 | |
| 616 | /* Compute ICMP checksum here */ |
| 617 | rap->icmp_cksum = in_cksum( (u_short *)rap, packetlen ); |
| 618 | |
| 619 | if (isbroadcast(sin)) |
| 620 | cc = sendbcastif(s, (char *)outpack, packetlen, |
| 621 | &interfaces[i]); |
| 622 | else if (ismulticast(sin)) |
| 623 | cc = sendmcastif( s, (char *)outpack, packetlen, sin, |
| 624 | &interfaces[i]); |
| 625 | else { |
| 626 | struct interface *ifp = &interfaces[i]; |
| 627 | /* |
| 628 | * Verify that the interface matches the destination |
| 629 | * address. |
| 630 | */ |
| 631 | if ((sin->sin_addr.s_addr & ifp->netmask.s_addr) == |
| 632 | (ifp->address.s_addr & ifp->netmask.s_addr)) { |
| 633 | if (debug) { |
| 634 | logdebug("Unicast to %s ", |
| 635 | pr_name(sin->sin_addr)); |
| 636 | logdebug("on interface %s, %s\n", |
| 637 | ifp->name, |
| 638 | pr_name(ifp->address)); |
| 639 | } |
| 640 | cc = sendto( s, (char *)outpack, packetlen, 0, |
| 641 | (struct sockaddr *)sin, |
| 642 | sizeof(struct sockaddr)); |
| 643 | } else |
| 644 | cc = packetlen; |
| 645 | } |
| 646 | if( cc < 0 || cc != packetlen ) { |
| 647 | if (cc < 0) { |
| 648 | logperror("sendto"); |
| 649 | } else { |
| 650 | logerr("wrote %s %d chars, ret=%d\n", |
| 651 | sendaddress, packetlen, cc ); |
| 652 | } |
| 653 | } |
| 654 | } |
| 655 | } |
| 656 | #endif |
| 657 | |
| 658 | /* |
| 659 | * P R _ T Y P E |
| 660 | * |
| 661 | * Convert an ICMP "type" field to a printable string. |
| 662 | */ |
| 663 | char * |
| 664 | pr_type(int t) |
| 665 | { |
| 666 | static char *ttab[] = { |
| 667 | "Echo Reply", |
| 668 | "ICMP 1", |
| 669 | "ICMP 2", |
| 670 | "Dest Unreachable", |
| 671 | "Source Quench", |
| 672 | "Redirect", |
| 673 | "ICMP 6", |
| 674 | "ICMP 7", |
| 675 | "Echo", |
| 676 | "Router Advertise", |
| 677 | "Router Solicitation", |
| 678 | "Time Exceeded", |
| 679 | "Parameter Problem", |
| 680 | "Timestamp", |
| 681 | "Timestamp Reply", |
| 682 | "Info Request", |
| 683 | "Info Reply", |
| 684 | "Netmask Request", |
| 685 | "Netmask Reply" |
| 686 | }; |
| 687 | |
| 688 | if ( t < 0 || t > 16 ) |
| 689 | return("OUT-OF-RANGE"); |
| 690 | |
| 691 | return(ttab[t]); |
| 692 | } |
| 693 | |
| 694 | /* |
| 695 | * P R _ N A M E |
| 696 | * |
| 697 | * Return a string name for the given IP address. |
| 698 | */ |
| 699 | char *pr_name(struct in_addr addr) |
| 700 | { |
| 701 | struct hostent *phe; |
| 702 | static char buf[80]; |
| 703 | |
| 704 | phe = gethostbyaddr((char *)&addr.s_addr, 4, AF_INET); |
| 705 | if (phe == NULL) |
| 706 | return( inet_ntoa(addr)); |
| 707 | snprintf(buf, sizeof(buf), "%s (%s)", phe->h_name, inet_ntoa(addr)); |
| 708 | return(buf); |
| 709 | } |
| 710 | |
| 711 | /* |
| 712 | * P R _ P A C K |
| 713 | * |
| 714 | * Print out the packet, if it came from us. This logic is necessary |
| 715 | * because ALL readers of the ICMP socket get a copy of ALL ICMP packets |
| 716 | * which arrive ('tis only fair). This permits multiple copies of this |
| 717 | * program to be run without having intermingled output (or statistics!). |
| 718 | */ |
| 719 | void |
| 720 | pr_pack(char *buf, int cc, struct sockaddr_in *from) |
| 721 | { |
| 722 | struct iphdr *ip; |
| 723 | struct icmphdr *icp; |
| 724 | int i; |
| 725 | int hlen; |
| 726 | |
| 727 | ip = (struct iphdr *) ALLIGN(buf); |
| 728 | hlen = ip->ihl << 2; |
| 729 | if (cc < hlen + 8) { |
| 730 | if (verbose) |
| 731 | logtrace("packet too short (%d bytes) from %s\n", cc, |
| 732 | pr_name(from->sin_addr)); |
| 733 | return; |
| 734 | } |
| 735 | cc -= hlen; |
| 736 | icp = (struct icmphdr *)ALLIGN(buf + hlen); |
| 737 | |
| 738 | switch (icp->type) { |
| 739 | case ICMP_ROUTER_ADVERTISEMENT: |
| 740 | { |
| 741 | struct icmp_ra *rap = (struct icmp_ra *)ALLIGN(icp); |
| 742 | struct icmp_ra_addr *ap; |
| 743 | |
| 744 | #ifdef RDISC_SERVER |
| 745 | if (responder) |
| 746 | break; |
| 747 | #endif |
| 748 | |
| 749 | /* TBD verify that the link is multicast or broadcast */ |
| 750 | /* XXX Find out the link it came in over? */ |
| 751 | if (in_cksum((u_short *)ALLIGN(buf+hlen), cc)) { |
| 752 | if (verbose) |
| 753 | logtrace("ICMP %s from %s: Bad checksum\n", |
| 754 | pr_type((int)rap->icmp_type), |
| 755 | pr_name(from->sin_addr)); |
| 756 | return; |
| 757 | } |
| 758 | if (rap->icmp_code != 0) { |
| 759 | if (verbose) |
| 760 | logtrace("ICMP %s from %s: Code = %d\n", |
| 761 | pr_type((int)rap->icmp_type), |
| 762 | pr_name(from->sin_addr), |
| 763 | rap->icmp_code); |
| 764 | return; |
| 765 | } |
| 766 | if (rap->icmp_num_addrs < 1) { |
| 767 | if (verbose) |
| 768 | logtrace("ICMP %s from %s: No addresses\n", |
| 769 | pr_type((int)rap->icmp_type), |
| 770 | pr_name(from->sin_addr)); |
| 771 | return; |
| 772 | } |
| 773 | if (rap->icmp_wpa < 2) { |
| 774 | if (verbose) |
| 775 | logtrace("ICMP %s from %s: Words/addr = %d\n", |
| 776 | pr_type((int)rap->icmp_type), |
| 777 | pr_name(from->sin_addr), |
| 778 | rap->icmp_wpa); |
| 779 | return; |
| 780 | } |
| 781 | if ((unsigned)cc < |
| 782 | 8 + rap->icmp_num_addrs * rap->icmp_wpa * 4) { |
| 783 | if (verbose) |
| 784 | logtrace("ICMP %s from %s: Too short %d, %d\n", |
| 785 | pr_type((int)rap->icmp_type), |
| 786 | pr_name(from->sin_addr), |
| 787 | cc, |
| 788 | 8 + rap->icmp_num_addrs * rap->icmp_wpa * 4); |
| 789 | return; |
| 790 | } |
| 791 | |
| 792 | if (verbose) |
| 793 | logtrace("ICMP %s from %s, lifetime %d\n", |
| 794 | pr_type((int)rap->icmp_type), |
| 795 | pr_name(from->sin_addr), |
| 796 | ntohs(rap->icmp_lifetime)); |
| 797 | |
| 798 | /* Check that at least one router address is a neighboor |
| 799 | * on the arriving link. |
| 800 | */ |
| 801 | for (i = 0; (unsigned)i < rap->icmp_num_addrs; i++) { |
| 802 | struct in_addr ina; |
| 803 | ap = (struct icmp_ra_addr *) |
| 804 | ALLIGN(buf + hlen + 8 + |
| 805 | i * rap->icmp_wpa * 4); |
| 806 | ina.s_addr = ap->ira_addr; |
| 807 | if (verbose) |
| 808 | logtrace("\taddress %s, preference 0x%x\n", |
| 809 | pr_name(ina), |
| 810 | (unsigned int)ntohl(ap->ira_preference)); |
| 811 | if (is_directly_connected(ina)) |
| 812 | record_router(ina, |
| 813 | ntohl(ap->ira_preference), |
| 814 | ntohs(rap->icmp_lifetime)); |
| 815 | } |
| 816 | nreceived++; |
| 817 | if (!forever) { |
| 818 | do_fork(); |
| 819 | forever = 1; |
| 820 | /* |
| 821 | * The next line was added so that the alarm is set for the new procces |
| 822 | * Fraser Gardiner Sun Microsystems Australia |
| 823 | */ |
| 824 | (void) alarm(TIMER_INTERVAL); |
| 825 | } |
| 826 | break; |
| 827 | } |
| 828 | |
| 829 | #ifdef RDISC_SERVER |
| 830 | case ICMP_ROUTER_SOLICITATION: |
| 831 | { |
| 832 | struct sockaddr_in sin; |
| 833 | |
| 834 | if (!responder) |
| 835 | break; |
| 836 | |
| 837 | /* TBD verify that the link is multicast or broadcast */ |
| 838 | /* XXX Find out the link it came in over? */ |
| 839 | |
| 840 | if (in_cksum((u_short *)ALLIGN(buf+hlen), cc)) { |
| 841 | if (verbose) |
| 842 | logtrace("ICMP %s from %s: Bad checksum\n", |
| 843 | pr_type((int)icp->type), |
| 844 | pr_name(from->sin_addr)); |
| 845 | return; |
| 846 | } |
| 847 | if (icp->code != 0) { |
| 848 | if (verbose) |
| 849 | logtrace("ICMP %s from %s: Code = %d\n", |
| 850 | pr_type((int)icp->type), |
| 851 | pr_name(from->sin_addr), |
| 852 | icp->code); |
| 853 | return; |
| 854 | } |
| 855 | |
| 856 | if (cc < ICMP_MINLEN) { |
| 857 | if (verbose) |
| 858 | logtrace("ICMP %s from %s: Too short %d, %d\n", |
| 859 | pr_type((int)icp->type), |
| 860 | pr_name(from->sin_addr), |
| 861 | cc, |
| 862 | ICMP_MINLEN); |
| 863 | return; |
| 864 | } |
| 865 | |
| 866 | if (verbose) |
| 867 | logtrace("ICMP %s from %s\n", |
| 868 | pr_type((int)icp->type), |
| 869 | pr_name(from->sin_addr)); |
| 870 | |
| 871 | /* Check that ip_src is either a neighboor |
| 872 | * on the arriving link or 0. |
| 873 | */ |
| 874 | sin.sin_family = AF_INET; |
| 875 | if (ip->saddr == 0) { |
| 876 | /* If it was sent to the broadcast address we respond |
| 877 | * to the broadcast address. |
| 878 | */ |
| 879 | if (IN_CLASSD(ntohl(ip->daddr))) |
| 880 | sin.sin_addr.s_addr = htonl(0xe0000001); |
| 881 | else |
| 882 | sin.sin_addr.s_addr = INADDR_BROADCAST; |
| 883 | /* Restart the timer when we broadcast */ |
| 884 | left_until_advertise = min_adv_int + |
| 885 | ((max_adv_int - min_adv_int) |
| 886 | * (random() % 1000)/1000); |
| 887 | } else { |
| 888 | sin.sin_addr.s_addr = ip->saddr; |
| 889 | if (!is_directly_connected(sin.sin_addr)) { |
| 890 | if (verbose) |
| 891 | logtrace("ICMP %s from %s: source not directly connected\n", |
| 892 | pr_type((int)icp->type), |
| 893 | pr_name(from->sin_addr)); |
| 894 | break; |
| 895 | } |
| 896 | } |
| 897 | nreceived++; |
| 898 | ntransmitted++; |
| 899 | advertise(&sin, lifetime); |
| 900 | break; |
| 901 | } |
| 902 | #endif |
| 903 | } |
| 904 | } |
| 905 | |
| 906 | |
| 907 | /* |
| 908 | * I N _ C K S U M |
| 909 | * |
| 910 | * Checksum routine for Internet Protocol family headers (C Version) |
| 911 | * |
| 912 | */ |
| 913 | #if BYTE_ORDER == LITTLE_ENDIAN |
| 914 | # define ODDBYTE(v) (v) |
| 915 | #elif BYTE_ORDER == BIG_ENDIAN |
| 916 | # define ODDBYTE(v) ((u_short)(v) << 8) |
| 917 | #else |
| 918 | # define ODDBYTE(v) htons((u_short)(v) << 8) |
| 919 | #endif |
| 920 | |
| 921 | u_short in_cksum(u_short *addr, int len) |
| 922 | { |
| 923 | register int nleft = len; |
| 924 | register u_short *w = addr; |
| 925 | register u_short answer; |
| 926 | register int sum = 0; |
| 927 | |
| 928 | /* |
| 929 | * Our algorithm is simple, using a 32 bit accumulator (sum), |
| 930 | * we add sequential 16 bit words to it, and at the end, fold |
| 931 | * back all the carry bits from the top 16 bits into the lower |
| 932 | * 16 bits. |
| 933 | */ |
| 934 | while( nleft > 1 ) { |
| 935 | sum += *w++; |
| 936 | nleft -= 2; |
| 937 | } |
| 938 | |
| 939 | /* mop up an odd byte, if necessary */ |
| 940 | if( nleft == 1 ) |
| 941 | sum += ODDBYTE(*(u_char *)w); /* le16toh() may be unavailable on old systems */ |
| 942 | |
| 943 | /* |
| 944 | * add back carry outs from top 16 bits to low 16 bits |
| 945 | */ |
| 946 | sum = (sum >> 16) + (sum & 0xffff); /* add hi 16 to low 16 */ |
| 947 | sum += (sum >> 16); /* add carry */ |
| 948 | answer = ~sum; /* truncate to 16 bits */ |
| 949 | return (answer); |
| 950 | } |
| 951 | |
| 952 | /* |
| 953 | * F I N I S H |
| 954 | * |
| 955 | * Print out statistics, and give up. |
| 956 | * Heavily buffered STDIO is used here, so that all the statistics |
| 957 | * will be written with 1 sys-write call. This is nice when more |
| 958 | * than one copy of the program is running on a terminal; it prevents |
| 959 | * the statistics output from becomming intermingled. |
| 960 | */ |
| 961 | void |
| 962 | finish() |
| 963 | { |
| 964 | #ifdef RDISC_SERVER |
| 965 | if (responder) { |
| 966 | /* Send out a packet with a preference so that all |
| 967 | * hosts will know that we are dead. |
| 968 | * |
| 969 | * Wrong comment, wrong code. |
| 970 | * ttl must be set to 0 instead. --ANK |
| 971 | */ |
| 972 | logerr("terminated\n"); |
| 973 | ntransmitted++; |
| 974 | advertise(&whereto, 0); |
| 975 | } |
| 976 | #endif |
| 977 | logtrace("\n----%s rdisc Statistics----\n", sendaddress ); |
| 978 | logtrace("%d packets transmitted, ", ntransmitted ); |
| 979 | logtrace("%d packets received, ", nreceived ); |
| 980 | logtrace("\n"); |
| 981 | (void) fflush(stdout); |
| 982 | exit(0); |
| 983 | } |
| 984 | |
| 985 | void |
| 986 | graceful_finish() |
| 987 | { |
| 988 | discard_table(); |
| 989 | finish(); |
| 990 | exit(0); |
| 991 | } |
| 992 | |
| 993 | |
| 994 | /* From libc/rpc/pmap_rmt.c */ |
| 995 | |
| 996 | int |
| 997 | sendbcast(int s, char *packet, int packetlen) |
| 998 | { |
| 999 | int i, cc; |
| 1000 | |
| 1001 | for (i = 0; i < num_interfaces; i++) { |
| 1002 | if ((interfaces[i].flags & (IFF_BROADCAST|IFF_POINTOPOINT)) == 0) |
| 1003 | continue; |
| 1004 | cc = sendbcastif(s, packet, packetlen, &interfaces[i]); |
| 1005 | if (cc!= packetlen) { |
| 1006 | return (cc); |
| 1007 | } |
| 1008 | } |
| 1009 | return (packetlen); |
| 1010 | } |
| 1011 | |
| 1012 | int |
| 1013 | sendbcastif(int s, char *packet, int packetlen, struct interface *ifp) |
| 1014 | { |
| 1015 | int on; |
| 1016 | int cc; |
| 1017 | struct sockaddr_in baddr; |
| 1018 | |
| 1019 | baddr.sin_family = AF_INET; |
| 1020 | baddr.sin_addr = ifp->bcastaddr; |
| 1021 | if (debug) |
| 1022 | logdebug("Broadcast to %s\n", |
| 1023 | pr_name(baddr.sin_addr)); |
| 1024 | on = 1; |
| 1025 | setsockopt(s, SOL_SOCKET, SO_BROADCAST, (char*)&on, sizeof(on)); |
| 1026 | cc = sendto(s, packet, packetlen, 0, |
| 1027 | (struct sockaddr *)&baddr, sizeof (struct sockaddr)); |
| 1028 | if (cc!= packetlen) { |
| 1029 | logperror("sendbcast: sendto"); |
| 1030 | logerr("Cannot send broadcast packet to %s\n", |
| 1031 | pr_name(baddr.sin_addr)); |
| 1032 | } |
| 1033 | on = 0; |
| 1034 | setsockopt(s, SOL_SOCKET, SO_BROADCAST, (char*)&on, sizeof(on)); |
| 1035 | return (cc); |
| 1036 | } |
| 1037 | |
| 1038 | int |
| 1039 | sendmcast(int s, char *packet, int packetlen, struct sockaddr_in *sin) |
| 1040 | { |
| 1041 | int i, cc; |
| 1042 | |
| 1043 | for (i = 0; i < num_interfaces; i++) { |
| 1044 | if ((interfaces[i].flags & (IFF_BROADCAST|IFF_POINTOPOINT|IFF_MULTICAST)) == 0) |
| 1045 | continue; |
| 1046 | cc = sendmcastif(s, packet, packetlen, sin, &interfaces[i]); |
| 1047 | if (cc!= packetlen) { |
| 1048 | return (cc); |
| 1049 | } |
| 1050 | } |
| 1051 | return (packetlen); |
| 1052 | } |
| 1053 | |
| 1054 | int |
| 1055 | sendmcastif(int s, char *packet, int packetlen, struct sockaddr_in *sin, |
| 1056 | struct interface *ifp) |
| 1057 | { |
| 1058 | int cc; |
| 1059 | struct ip_mreqn mreq; |
| 1060 | |
| 1061 | memset(&mreq, 0, sizeof(mreq)); |
| 1062 | mreq.imr_ifindex = ifp->ifindex; |
| 1063 | mreq.imr_address = ifp->localaddr; |
| 1064 | if (debug) |
| 1065 | logdebug("Multicast to interface %s, %s\n", |
| 1066 | ifp->name, |
| 1067 | pr_name(mreq.imr_address)); |
| 1068 | if (setsockopt(s, IPPROTO_IP, IP_MULTICAST_IF, |
| 1069 | (char *)&mreq, |
| 1070 | sizeof(mreq)) < 0) { |
| 1071 | logperror("setsockopt (IP_MULTICAST_IF)"); |
| 1072 | logerr("Cannot send multicast packet over interface %s, %s\n", |
| 1073 | ifp->name, |
| 1074 | pr_name(mreq.imr_address)); |
| 1075 | return (-1); |
| 1076 | } |
| 1077 | cc = sendto(s, packet, packetlen, 0, |
| 1078 | (struct sockaddr *)sin, sizeof (struct sockaddr)); |
| 1079 | if (cc!= packetlen) { |
| 1080 | logperror("sendmcast: sendto"); |
| 1081 | logerr("Cannot send multicast packet over interface %s, %s\n", |
| 1082 | ifp->name, pr_name(mreq.imr_address)); |
| 1083 | } |
| 1084 | return (cc); |
| 1085 | } |
| 1086 | |
| 1087 | void |
| 1088 | init() |
| 1089 | { |
| 1090 | initifs(); |
| 1091 | #ifdef RDISC_SERVER |
| 1092 | { |
| 1093 | int i; |
| 1094 | for (i = 0; i < interfaces_size; i++) |
| 1095 | interfaces[i].preference = preference; |
| 1096 | } |
| 1097 | #endif |
| 1098 | } |
| 1099 | |
| 1100 | void |
| 1101 | initifs() |
| 1102 | { |
| 1103 | int sock; |
| 1104 | struct ifconf ifc; |
| 1105 | struct ifreq ifreq, *ifr; |
| 1106 | struct sockaddr_in *sin; |
| 1107 | int n, i; |
| 1108 | char *buf; |
| 1109 | int numifs; |
| 1110 | unsigned bufsize; |
| 1111 | |
| 1112 | sock = socket(AF_INET, SOCK_DGRAM, 0); |
| 1113 | if (sock < 0) { |
| 1114 | logperror("initifs: socket"); |
| 1115 | return; |
| 1116 | } |
| 1117 | #ifdef SIOCGIFNUM |
| 1118 | if (ioctl(sock, SIOCGIFNUM, (char *)&numifs) < 0) { |
| 1119 | numifs = MAXIFS; |
| 1120 | } |
| 1121 | #else |
| 1122 | numifs = MAXIFS; |
| 1123 | #endif |
| 1124 | bufsize = numifs * sizeof(struct ifreq); |
| 1125 | buf = (char *)malloc(bufsize); |
| 1126 | if (buf == NULL) { |
| 1127 | logerr("out of memory\n"); |
| 1128 | (void) close(sock); |
| 1129 | return; |
| 1130 | } |
| 1131 | if (interfaces != NULL) |
| 1132 | (void) free(interfaces); |
| 1133 | interfaces = (struct interface *)ALLIGN(malloc(numifs * |
| 1134 | sizeof(struct interface))); |
| 1135 | if (interfaces == NULL) { |
| 1136 | logerr("out of memory\n"); |
| 1137 | (void) close(sock); |
| 1138 | (void) free(buf); |
| 1139 | return; |
| 1140 | } |
| 1141 | interfaces_size = numifs; |
| 1142 | |
| 1143 | ifc.ifc_len = bufsize; |
| 1144 | ifc.ifc_buf = buf; |
| 1145 | if (ioctl(sock, SIOCGIFCONF, (char *)&ifc) < 0) { |
| 1146 | logperror("initifs: ioctl (get interface configuration)"); |
| 1147 | (void) close(sock); |
| 1148 | (void) free(buf); |
| 1149 | return; |
| 1150 | } |
| 1151 | ifr = ifc.ifc_req; |
| 1152 | for (i = 0, n = ifc.ifc_len/sizeof (struct ifreq); n > 0; n--, ifr++) { |
| 1153 | ifreq = *ifr; |
| 1154 | if (strlen(ifreq.ifr_name) >= IFNAMSIZ) |
| 1155 | continue; |
| 1156 | if (ioctl(sock, SIOCGIFFLAGS, (char *)&ifreq) < 0) { |
| 1157 | logperror("initifs: ioctl (get interface flags)"); |
| 1158 | continue; |
| 1159 | } |
| 1160 | if (ifr->ifr_addr.sa_family != AF_INET) |
| 1161 | continue; |
| 1162 | if ((ifreq.ifr_flags & IFF_UP) == 0) |
| 1163 | continue; |
| 1164 | if (ifreq.ifr_flags & IFF_LOOPBACK) |
| 1165 | continue; |
| 1166 | if ((ifreq.ifr_flags & (IFF_MULTICAST|IFF_BROADCAST|IFF_POINTOPOINT)) == 0) |
| 1167 | continue; |
| 1168 | strncpy(interfaces[i].name, ifr->ifr_name, IFNAMSIZ-1); |
| 1169 | |
| 1170 | sin = (struct sockaddr_in *)ALLIGN(&ifr->ifr_addr); |
| 1171 | interfaces[i].localaddr = sin->sin_addr; |
| 1172 | interfaces[i].flags = ifreq.ifr_flags; |
| 1173 | interfaces[i].netmask.s_addr = (__u32)0xffffffff; |
| 1174 | if (ioctl(sock, SIOCGIFINDEX, (char *)&ifreq) < 0) { |
| 1175 | logperror("initifs: ioctl (get ifindex)"); |
| 1176 | continue; |
| 1177 | } |
| 1178 | interfaces[i].ifindex = ifreq.ifr_ifindex; |
| 1179 | if (ifreq.ifr_flags & IFF_POINTOPOINT) { |
| 1180 | if (ioctl(sock, SIOCGIFDSTADDR, (char *)&ifreq) < 0) { |
| 1181 | logperror("initifs: ioctl (get destination addr)"); |
| 1182 | continue; |
| 1183 | } |
| 1184 | sin = (struct sockaddr_in *)ALLIGN(&ifreq.ifr_addr); |
| 1185 | /* A pt-pt link is identified by the remote address */ |
| 1186 | interfaces[i].address = sin->sin_addr; |
| 1187 | interfaces[i].remoteaddr = sin->sin_addr; |
| 1188 | /* Simulate broadcast for pt-pt */ |
| 1189 | interfaces[i].bcastaddr = sin->sin_addr; |
| 1190 | interfaces[i].flags |= IFF_BROADCAST; |
| 1191 | } else { |
| 1192 | /* Non pt-pt links are identified by the local address */ |
| 1193 | interfaces[i].address = interfaces[i].localaddr; |
| 1194 | interfaces[i].remoteaddr = interfaces[i].address; |
| 1195 | if (ioctl(sock, SIOCGIFNETMASK, (char *)&ifreq) < 0) { |
| 1196 | logperror("initifs: ioctl (get netmask)"); |
| 1197 | continue; |
| 1198 | } |
| 1199 | sin = (struct sockaddr_in *)ALLIGN(&ifreq.ifr_addr); |
| 1200 | interfaces[i].netmask = sin->sin_addr; |
| 1201 | if (ifreq.ifr_flags & IFF_BROADCAST) { |
| 1202 | if (ioctl(sock, SIOCGIFBRDADDR, (char *)&ifreq) < 0) { |
| 1203 | logperror("initifs: ioctl (get broadcast address)"); |
| 1204 | continue; |
| 1205 | } |
| 1206 | sin = (struct sockaddr_in *)ALLIGN(&ifreq.ifr_addr); |
| 1207 | interfaces[i].bcastaddr = sin->sin_addr; |
| 1208 | } |
| 1209 | } |
| 1210 | #ifdef notdef |
| 1211 | if (debug) |
| 1212 | logdebug("Found interface %s, flags 0x%x\n", |
| 1213 | pr_name(interfaces[i].localaddr), |
| 1214 | interfaces[i].flags); |
| 1215 | #endif |
| 1216 | i++; |
| 1217 | } |
| 1218 | num_interfaces = i; |
| 1219 | #ifdef notdef |
| 1220 | if (debug) |
| 1221 | logdebug("Found %d interfaces\n", num_interfaces); |
| 1222 | #endif |
| 1223 | (void) close(sock); |
| 1224 | (void) free(buf); |
| 1225 | } |
| 1226 | |
| 1227 | int |
| 1228 | join(int sock, struct sockaddr_in *sin) |
| 1229 | { |
| 1230 | int i, j; |
| 1231 | struct ip_mreqn mreq; |
| 1232 | int joined[num_interfaces]; |
| 1233 | |
| 1234 | memset(joined, 0, sizeof(joined)); |
| 1235 | |
| 1236 | if (isbroadcast(sin)) |
| 1237 | return (0); |
| 1238 | |
| 1239 | mreq.imr_multiaddr = sin->sin_addr; |
| 1240 | for (i = 0; i < num_interfaces; i++) { |
| 1241 | for (j = 0; j < i; j++) { |
| 1242 | if (joined[j] == interfaces[i].ifindex) |
| 1243 | break; |
| 1244 | } |
| 1245 | if (j != i) |
| 1246 | continue; |
| 1247 | |
| 1248 | mreq.imr_ifindex = interfaces[i].ifindex; |
| 1249 | mreq.imr_address.s_addr = 0; |
| 1250 | |
| 1251 | if (setsockopt(sock, IPPROTO_IP, IP_ADD_MEMBERSHIP, |
| 1252 | (char *)&mreq, sizeof(mreq)) < 0) { |
| 1253 | logperror("setsockopt (IP_ADD_MEMBERSHIP)"); |
| 1254 | return (-1); |
| 1255 | } |
| 1256 | |
| 1257 | joined[i] = interfaces[i].ifindex; |
| 1258 | } |
| 1259 | return (0); |
| 1260 | } |
| 1261 | |
| 1262 | int support_multicast() |
| 1263 | { |
| 1264 | int sock; |
| 1265 | u_char ttl = 1; |
| 1266 | |
| 1267 | sock = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP); |
| 1268 | if (sock < 0) { |
| 1269 | logperror("support_multicast: socket"); |
| 1270 | return (0); |
| 1271 | } |
| 1272 | |
| 1273 | if (setsockopt(sock, IPPROTO_IP, IP_MULTICAST_TTL, |
| 1274 | (char *)&ttl, sizeof(ttl)) < 0) { |
| 1275 | (void) close(sock); |
| 1276 | return (0); |
| 1277 | } |
| 1278 | (void) close(sock); |
| 1279 | return (1); |
| 1280 | } |
| 1281 | |
| 1282 | int |
| 1283 | is_directly_connected(struct in_addr in) |
| 1284 | { |
| 1285 | int i; |
| 1286 | |
| 1287 | for (i = 0; i < num_interfaces; i++) { |
| 1288 | /* Check that the subnetwork numbers match */ |
| 1289 | |
| 1290 | if ((in.s_addr & interfaces[i].netmask.s_addr ) == |
| 1291 | (interfaces[i].remoteaddr.s_addr & interfaces[i].netmask.s_addr)) |
| 1292 | return (1); |
| 1293 | } |
| 1294 | return (0); |
| 1295 | } |
| 1296 | |
| 1297 | /* |
| 1298 | * TABLES |
| 1299 | */ |
| 1300 | struct table { |
| 1301 | struct in_addr router; |
| 1302 | int preference; |
| 1303 | int remaining_time; |
| 1304 | int in_kernel; |
| 1305 | struct table *next; |
| 1306 | }; |
| 1307 | |
| 1308 | struct table *table; |
| 1309 | |
| 1310 | struct table * |
| 1311 | find_router(struct in_addr addr) |
| 1312 | { |
| 1313 | struct table *tp; |
| 1314 | |
| 1315 | tp = table; |
| 1316 | while (tp) { |
| 1317 | if (tp->router.s_addr == addr.s_addr) |
| 1318 | return (tp); |
| 1319 | tp = tp->next; |
| 1320 | } |
| 1321 | return (NULL); |
| 1322 | } |
| 1323 | |
| 1324 | int max_preference(void) |
| 1325 | { |
| 1326 | struct table *tp; |
| 1327 | int max = (int)INELIGIBLE_PREF; |
| 1328 | |
| 1329 | tp = table; |
| 1330 | while (tp) { |
| 1331 | if (tp->preference > max) |
| 1332 | max = tp->preference; |
| 1333 | tp = tp->next; |
| 1334 | } |
| 1335 | return (max); |
| 1336 | } |
| 1337 | |
| 1338 | |
| 1339 | /* Note: this might leave the kernel with no default route for a short time. */ |
| 1340 | void |
| 1341 | age_table(int time) |
| 1342 | { |
| 1343 | struct table **tpp, *tp; |
| 1344 | int recalculate_max = 0; |
| 1345 | int max = max_preference(); |
| 1346 | |
| 1347 | tpp = &table; |
| 1348 | while (*tpp != NULL) { |
| 1349 | tp = *tpp; |
| 1350 | tp->remaining_time -= time; |
| 1351 | if (tp->remaining_time <= 0) { |
| 1352 | *tpp = tp->next; |
| 1353 | if (tp->in_kernel) |
| 1354 | del_route(tp->router); |
| 1355 | if (best_preference && |
| 1356 | tp->preference == max) |
| 1357 | recalculate_max++; |
| 1358 | free((char *)tp); |
| 1359 | } else { |
| 1360 | tpp = &tp->next; |
| 1361 | } |
| 1362 | } |
| 1363 | if (recalculate_max) { |
| 1364 | int max = max_preference(); |
| 1365 | |
| 1366 | if (max != INELIGIBLE_PREF) { |
| 1367 | tp = table; |
| 1368 | while (tp) { |
| 1369 | if (tp->preference == max && !tp->in_kernel) { |
| 1370 | add_route(tp->router); |
| 1371 | tp->in_kernel++; |
| 1372 | } |
| 1373 | tp = tp->next; |
| 1374 | } |
| 1375 | } |
| 1376 | } |
| 1377 | } |
| 1378 | |
| 1379 | void discard_table(void) |
| 1380 | { |
| 1381 | struct table **tpp, *tp; |
| 1382 | |
| 1383 | tpp = &table; |
| 1384 | while (*tpp != NULL) { |
| 1385 | tp = *tpp; |
| 1386 | *tpp = tp->next; |
| 1387 | if (tp->in_kernel) |
| 1388 | del_route(tp->router); |
| 1389 | free((char *)tp); |
| 1390 | } |
| 1391 | } |
| 1392 | |
| 1393 | |
| 1394 | void |
| 1395 | record_router(struct in_addr router, int preference, int ttl) |
| 1396 | { |
| 1397 | struct table *tp; |
| 1398 | int old_max = max_preference(); |
| 1399 | int changed_up = 0; /* max preference could have increased */ |
| 1400 | int changed_down = 0; /* max preference could have decreased */ |
| 1401 | |
| 1402 | if (ttl < 4) |
| 1403 | preference = INELIGIBLE_PREF; |
| 1404 | |
| 1405 | if (debug) |
| 1406 | logdebug("Recording %s, ttl %d, preference 0x%x\n", |
| 1407 | pr_name(router), |
| 1408 | ttl, |
| 1409 | preference); |
| 1410 | tp = find_router(router); |
| 1411 | if (tp) { |
| 1412 | if (tp->preference > preference && |
| 1413 | tp->preference == old_max) |
| 1414 | changed_down++; |
| 1415 | else if (preference > tp->preference) |
| 1416 | changed_up++; |
| 1417 | tp->preference = preference; |
| 1418 | tp->remaining_time = ttl; |
| 1419 | } else { |
| 1420 | if (preference > old_max) |
| 1421 | changed_up++; |
| 1422 | tp = (struct table *)ALLIGN(malloc(sizeof(struct table))); |
| 1423 | if (tp == NULL) { |
| 1424 | logerr("Out of memory\n"); |
| 1425 | return; |
| 1426 | } |
| 1427 | tp->router = router; |
| 1428 | tp->preference = preference; |
| 1429 | tp->remaining_time = ttl; |
| 1430 | tp->in_kernel = 0; |
| 1431 | tp->next = table; |
| 1432 | table = tp; |
| 1433 | } |
| 1434 | if (!tp->in_kernel && |
| 1435 | (!best_preference || tp->preference == max_preference()) && |
| 1436 | tp->preference != INELIGIBLE_PREF) { |
| 1437 | add_route(tp->router); |
| 1438 | tp->in_kernel++; |
| 1439 | } |
| 1440 | if (tp->preference == INELIGIBLE_PREF && tp->in_kernel) { |
| 1441 | del_route(tp->router); |
| 1442 | tp->in_kernel = 0; |
| 1443 | } |
| 1444 | if (best_preference && changed_down) { |
| 1445 | /* Check if we should add routes */ |
| 1446 | int new_max = max_preference(); |
| 1447 | if (new_max != INELIGIBLE_PREF) { |
| 1448 | tp = table; |
| 1449 | while (tp) { |
| 1450 | if (tp->preference == new_max && |
| 1451 | !tp->in_kernel) { |
| 1452 | add_route(tp->router); |
| 1453 | tp->in_kernel++; |
| 1454 | } |
| 1455 | tp = tp->next; |
| 1456 | } |
| 1457 | } |
| 1458 | } |
| 1459 | if (best_preference && (changed_up || changed_down)) { |
| 1460 | /* Check if we should remove routes already in the kernel */ |
| 1461 | int new_max = max_preference(); |
| 1462 | tp = table; |
| 1463 | while (tp) { |
| 1464 | if (tp->preference < new_max && tp->in_kernel) { |
| 1465 | del_route(tp->router); |
| 1466 | tp->in_kernel = 0; |
| 1467 | } |
| 1468 | tp = tp->next; |
| 1469 | } |
| 1470 | } |
| 1471 | } |
| 1472 | |
| 1473 | void |
| 1474 | add_route(struct in_addr addr) |
| 1475 | { |
| 1476 | if (debug) |
| 1477 | logdebug("Add default route to %s\n", pr_name(addr)); |
| 1478 | rtioctl(addr, SIOCADDRT); |
| 1479 | } |
| 1480 | |
| 1481 | void |
| 1482 | del_route(struct in_addr addr) |
| 1483 | { |
| 1484 | if (debug) |
| 1485 | logdebug("Delete default route to %s\n", pr_name(addr)); |
| 1486 | rtioctl(addr, SIOCDELRT); |
| 1487 | } |
| 1488 | |
| 1489 | void |
| 1490 | rtioctl(struct in_addr addr, int op) |
| 1491 | { |
| 1492 | int sock; |
| 1493 | struct rtentry rt; |
| 1494 | struct sockaddr_in *sin; |
| 1495 | |
| 1496 | memset((char *)&rt, 0, sizeof(struct rtentry)); |
| 1497 | rt.rt_dst.sa_family = AF_INET; |
| 1498 | rt.rt_gateway.sa_family = AF_INET; |
| 1499 | rt.rt_genmask.sa_family = AF_INET; |
| 1500 | sin = (struct sockaddr_in *)ALLIGN(&rt.rt_gateway); |
| 1501 | sin->sin_addr = addr; |
| 1502 | rt.rt_flags = RTF_UP | RTF_GATEWAY; |
| 1503 | |
| 1504 | sock = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP); |
| 1505 | if (sock < 0) { |
| 1506 | logperror("rtioctl: socket"); |
| 1507 | return; |
| 1508 | } |
| 1509 | if (ioctl(sock, op, (char *)&rt) < 0) { |
| 1510 | if (!(op == SIOCADDRT && errno == EEXIST)) |
| 1511 | logperror("ioctl (add/delete route)"); |
| 1512 | } |
| 1513 | (void) close(sock); |
| 1514 | } |
| 1515 | |
| 1516 | /* |
| 1517 | * LOGGER |
| 1518 | */ |
| 1519 | |
| 1520 | void initlog(void) |
| 1521 | { |
| 1522 | logging++; |
| 1523 | openlog("in.rdiscd", LOG_PID | LOG_CONS, LOG_DAEMON); |
| 1524 | } |
| 1525 | |
| 1526 | |
| 1527 | void |
| 1528 | logperror(char *str) |
| 1529 | { |
| 1530 | if (logging) |
| 1531 | syslog(LOG_ERR, "%s: %m", str); |
| 1532 | else |
| 1533 | (void) fprintf(stderr, "%s: %s\n", str, strerror(errno)); |
| 1534 | } |