main.c revision 222745
1/* 2 * Copyright (c) 2002-2003,2010 Luigi Rizzo 3 * Copyright (c) 1996 Alex Nash, Paul Traina, Poul-Henning Kamp 4 * Copyright (c) 1994 Ugen J.S.Antsilevich 5 * 6 * Idea and grammar partially left from: 7 * Copyright (c) 1993 Daniel Boulet 8 * 9 * Redistribution and use in source forms, with and without modification, 10 * are permitted provided that this entire comment appears intact. 11 * 12 * Redistribution in binary form may occur without any restrictions. 13 * Obviously, it would be nice if you gave credit where credit is due 14 * but requiring it would be too onerous. 15 * 16 * This software is provided ``AS IS'' without any warranties of any kind. 17 * 18 * Command line interface for IP firewall facility 19 * 20 * $FreeBSD: head/sbin/ipfw/main.c 222745 2011-06-06 11:10:38Z ae $ 21 */ 22 23#include <sys/wait.h> 24#include <ctype.h> 25#include <err.h> 26#include <errno.h> 27#include <signal.h> 28#include <stdio.h> 29#include <stdlib.h> 30#include <string.h> 31#include <sysexits.h> 32#include <unistd.h> 33 34#include "ipfw2.h" 35 36static void 37help(void) 38{ 39 fprintf(stderr, 40"ipfw syntax summary (but please do read the ipfw(8) manpage):\n\n" 41"\tipfw [-abcdefhnNqStTv] <command>\n\n" 42"where <command> is one of the following:\n\n" 43"add [num] [set N] [prob x] RULE-BODY\n" 44"{pipe|queue} N config PIPE-BODY\n" 45"[pipe|queue] {zero|delete|show} [N{,N}]\n" 46"nat N config {ip IPADDR|if IFNAME|log|deny_in|same_ports|unreg_only|reset|\n" 47" reverse|proxy_only|redirect_addr linkspec|\n" 48" redirect_port linkspec|redirect_proto linkspec}\n" 49"set [disable N... enable N...] | move [rule] X to Y | swap X Y | show\n" 50"set N {show|list|zero|resetlog|delete} [N{,N}] | flush\n" 51"table N {add ip[/bits] [value] | delete ip[/bits] | flush | list}\n" 52"table all {flush | list}\n" 53"\n" 54"RULE-BODY: check-state [PARAMS] | ACTION [PARAMS] ADDR [OPTION_LIST]\n" 55"ACTION: check-state | allow | count | deny | unreach{,6} CODE |\n" 56" skipto N | {divert|tee} PORT | forward ADDR |\n" 57" pipe N | queue N | nat N | setfib FIB | reass\n" 58"PARAMS: [log [logamount LOGLIMIT]] [altq QUEUE_NAME]\n" 59"ADDR: [ MAC dst src ether_type ] \n" 60" [ ip from IPADDR [ PORT ] to IPADDR [ PORTLIST ] ]\n" 61" [ ipv6|ip6 from IP6ADDR [ PORT ] to IP6ADDR [ PORTLIST ] ]\n" 62"IPADDR: [not] { any | me | ip/bits{x,y,z} | table(t[,v]) | IPLIST }\n" 63"IP6ADDR: [not] { any | me | me6 | ip6/bits | IP6LIST }\n" 64"IP6LIST: { ip6 | ip6/bits }[,IP6LIST]\n" 65"IPLIST: { ip | ip/bits | ip:mask }[,IPLIST]\n" 66"OPTION_LIST: OPTION [OPTION_LIST]\n" 67"OPTION: bridged | diverted | diverted-loopback | diverted-output |\n" 68" {dst-ip|src-ip} IPADDR | {dst-ip6|src-ip6|dst-ipv6|src-ipv6} IP6ADDR |\n" 69" {dst-port|src-port} LIST |\n" 70" estab | frag | {gid|uid} N | icmptypes LIST | in | out | ipid LIST |\n" 71" iplen LIST | ipoptions SPEC | ipprecedence | ipsec | iptos SPEC |\n" 72" ipttl LIST | ipversion VER | keep-state | layer2 | limit ... |\n" 73" icmp6types LIST | ext6hdr LIST | flow-id N[,N] | fib FIB |\n" 74" mac ... | mac-type LIST | proto LIST | {recv|xmit|via} {IF|IPADDR} |\n" 75" setup | {tcpack|tcpseq|tcpwin} NN | tcpflags SPEC | tcpoptions SPEC |\n" 76" tcpdatalen LIST | verrevpath | versrcreach | antispoof\n" 77); 78 79 exit(0); 80} 81 82/* 83 * Called with the arguments, including program name because getopt 84 * wants it to be present. 85 * Returns 0 if successful, 1 if empty command, errx() in case of errors. 86 * First thing we do is process parameters creating an argv[] array 87 * which includes the program name and a NULL entry at the end. 88 * If we are called with a single string, we split it on whitespace. 89 * Also, arguments with a trailing ',' are joined to the next one. 90 * The pointers (av[]) and data are in a a single chunk of memory. 91 * av[0] points to the original program name, all other entries 92 * point into the allocated chunk. 93 */ 94static int 95ipfw_main(int oldac, char **oldav) 96{ 97 int ch, ac; 98 const char *errstr; 99 char **av, **save_av; 100 int do_acct = 0; /* Show packet/byte count */ 101 int try_next = 0; /* set if pipe cmd not found */ 102 int av_size; /* compute the av size */ 103 char *av_p; /* used to build the av list */ 104 105#define WHITESP " \t\f\v\n\r" 106 if (oldac < 2) 107 return 1; /* need at least one argument */ 108 109 if (oldac == 2) { 110 /* 111 * If we are called with one argument, try to split it into 112 * words for subsequent parsing. Spaces after a ',' are 113 * removed by copying the string in-place. 114 */ 115 char *arg = oldav[1]; /* The string is the first arg. */ 116 int l = strlen(arg); 117 int copy = 0; /* 1 if we need to copy, 0 otherwise */ 118 int i, j; 119 120 for (i = j = 0; i < l; i++) { 121 if (arg[i] == '#') /* comment marker */ 122 break; 123 if (copy) { 124 arg[j++] = arg[i]; 125 copy = !index("," WHITESP, arg[i]); 126 } else { 127 copy = !index(WHITESP, arg[i]); 128 if (copy) 129 arg[j++] = arg[i]; 130 } 131 } 132 if (!copy && j > 0) /* last char was a 'blank', remove it */ 133 j--; 134 l = j; /* the new argument length */ 135 arg[j++] = '\0'; 136 if (l == 0) /* empty string! */ 137 return 1; 138 139 /* 140 * First, count number of arguments. Because of the previous 141 * processing, this is just the number of blanks plus 1. 142 */ 143 for (i = 0, ac = 1; i < l; i++) 144 if (index(WHITESP, arg[i]) != NULL) 145 ac++; 146 147 /* 148 * Allocate the argument list structure as a single block 149 * of memory, containing pointers and the argument 150 * strings. We include one entry for the program name 151 * because getopt expects it, and a NULL at the end 152 * to simplify further parsing. 153 */ 154 ac++; /* add 1 for the program name */ 155 av_size = (ac+1) * sizeof(char *) + l + 1; 156 av = safe_calloc(av_size, 1); 157 158 /* 159 * Init the argument pointer to the end of the array 160 * and copy arguments from arg[] to av[]. For each one, 161 * j is the initial character, i is the one past the end. 162 */ 163 av_p = (char *)&av[ac+1]; 164 for (ac = 1, i = j = 0; i < l; i++) { 165 if (index(WHITESP, arg[i]) != NULL || i == l-1) { 166 if (i == l-1) 167 i++; 168 bcopy(arg+j, av_p, i-j); 169 av[ac] = av_p; 170 av_p += i-j; /* the lenght of the string */ 171 *av_p++ = '\0'; 172 ac++; 173 j = i + 1; 174 } 175 } 176 } else { 177 /* 178 * If an argument ends with ',' join with the next one. 179 */ 180 int first, i, l=0; 181 182 /* 183 * Allocate the argument list structure as a single block 184 * of memory, containing both pointers and the argument 185 * strings. We include some space for the program name 186 * because getopt expects it. 187 * We add an extra pointer to the end of the array, 188 * to make simpler further parsing. 189 */ 190 for (i=0; i<oldac; i++) 191 l += strlen(oldav[i]); 192 193 av_size = (oldac+1) * sizeof(char *) + l + oldac; 194 av = safe_calloc(av_size, 1); 195 196 /* 197 * Init the argument pointer to the end of the array 198 * and copy arguments from arg[] to av[] 199 */ 200 av_p = (char *)&av[oldac+1]; 201 for (first = i = ac = 1, l = 0; i < oldac; i++) { 202 char *arg = oldav[i]; 203 int k = strlen(arg); 204 205 l += k; 206 if (arg[k-1] != ',' || i == oldac-1) { 207 /* Time to copy. */ 208 av[ac] = av_p; 209 for (l=0; first <= i; first++) { 210 strcat(av_p, oldav[first]); 211 av_p += strlen(oldav[first]); 212 } 213 *av_p++ = '\0'; 214 ac++; 215 l = 0; 216 first = i+1; 217 } 218 } 219 } 220 221 /* 222 * set the progname pointer to the original string 223 * and terminate the array with null 224 */ 225 av[0] = oldav[0]; 226 av[ac] = NULL; 227 228 /* Set the force flag for non-interactive processes */ 229 if (!co.do_force) 230 co.do_force = !isatty(STDIN_FILENO); 231 232#ifdef EMULATE_SYSCTL /* sysctl emulation */ 233 if ( ac >= 2 && !strcmp(av[1], "sysctl")) { 234 char *s; 235 int i; 236 237 if (ac != 3) { 238 printf( "sysctl emulation usage:\n" 239 " ipfw sysctl name[=value]\n" 240 " ipfw sysctl -a\n"); 241 return 0; 242 } 243 s = index(av[2], '='); 244 if (s == NULL) { 245 s = !strcmp(av[2], "-a") ? NULL : av[2]; 246 sysctlbyname(s, NULL, NULL, NULL, 0); 247 } else { /* ipfw sysctl x.y.z=value */ 248 /* assume an INT value, will extend later */ 249 if (s[1] == '\0') { 250 printf("ipfw sysctl: missing value\n\n"); 251 return 0; 252 } 253 *s = '\0'; 254 i = strtol(s+1, NULL, 0); 255 sysctlbyname(av[2], NULL, NULL, &i, sizeof(int)); 256 } 257 return 0; 258 } 259#endif 260 261 /* Save arguments for final freeing of memory. */ 262 save_av = av; 263 264 optind = optreset = 1; /* restart getopt() */ 265 while ((ch = getopt(ac, av, "abcdefhinNqs:STtv")) != -1) 266 switch (ch) { 267 case 'a': 268 do_acct = 1; 269 break; 270 271 case 'b': 272 co.comment_only = 1; 273 co.do_compact = 1; 274 break; 275 276 case 'c': 277 co.do_compact = 1; 278 break; 279 280 case 'd': 281 co.do_dynamic = 1; 282 break; 283 284 case 'e': 285 co.do_expired = 1; 286 break; 287 288 case 'f': 289 co.do_force = 1; 290 break; 291 292 case 'h': /* help */ 293 free(save_av); 294 help(); 295 break; /* NOTREACHED */ 296 297 case 'i': 298 co.do_value_as_ip = 1; 299 break; 300 301 case 'n': 302 co.test_only = 1; 303 break; 304 305 case 'N': 306 co.do_resolv = 1; 307 break; 308 309 case 'q': 310 co.do_quiet = 1; 311 break; 312 313 case 's': /* sort */ 314 co.do_sort = atoi(optarg); 315 break; 316 317 case 'S': 318 co.show_sets = 1; 319 break; 320 321 case 't': 322 co.do_time = 1; 323 break; 324 325 case 'T': 326 co.do_time = 2; /* numeric timestamp */ 327 break; 328 329 case 'v': /* verbose */ 330 co.verbose = 1; 331 break; 332 333 default: 334 free(save_av); 335 return 1; 336 } 337 338 ac -= optind; 339 av += optind; 340 NEED1("bad arguments, for usage summary ``ipfw''"); 341 342 /* 343 * An undocumented behaviour of ipfw1 was to allow rule numbers first, 344 * e.g. "100 add allow ..." instead of "add 100 allow ...". 345 * In case, swap first and second argument to get the normal form. 346 */ 347 if (ac > 1 && isdigit(*av[0])) { 348 char *p = av[0]; 349 350 av[0] = av[1]; 351 av[1] = p; 352 } 353 354 /* 355 * Optional: pipe, queue or nat. 356 */ 357 co.do_nat = 0; 358 co.do_pipe = 0; 359 co.use_set = 0; 360 if (!strncmp(*av, "nat", strlen(*av))) 361 co.do_nat = 1; 362 else if (!strncmp(*av, "pipe", strlen(*av))) 363 co.do_pipe = 1; 364 else if (_substrcmp(*av, "queue") == 0) 365 co.do_pipe = 2; 366 else if (_substrcmp(*av, "flowset") == 0) 367 co.do_pipe = 2; 368 else if (_substrcmp(*av, "sched") == 0) 369 co.do_pipe = 3; 370 else if (!strncmp(*av, "set", strlen(*av))) { 371 if (ac > 1 && isdigit(av[1][0])) { 372 co.use_set = strtonum(av[1], 0, resvd_set_number, 373 &errstr); 374 if (errstr) 375 errx(EX_DATAERR, 376 "invalid set number %s\n", av[1]); 377 ac -= 2; av += 2; co.use_set++; 378 } 379 } 380 381 if (co.do_pipe || co.do_nat) { 382 ac--; 383 av++; 384 } 385 NEED1("missing command"); 386 387 /* 388 * For pipes, queues and nats we normally say 'nat|pipe NN config' 389 * but the code is easier to parse as 'nat|pipe config NN' 390 * so we swap the two arguments. 391 */ 392 if ((co.do_pipe || co.do_nat) && ac > 1 && isdigit(*av[0])) { 393 char *p = av[0]; 394 395 av[0] = av[1]; 396 av[1] = p; 397 } 398 399 if (co.use_set == 0) { 400 if (_substrcmp(*av, "add") == 0) 401 ipfw_add(av); 402 else if (co.do_nat && _substrcmp(*av, "show") == 0) 403 ipfw_show_nat(ac, av); 404 else if (co.do_pipe && _substrcmp(*av, "config") == 0) 405 ipfw_config_pipe(ac, av); 406 else if (co.do_nat && _substrcmp(*av, "config") == 0) 407 ipfw_config_nat(ac, av); 408 else if (_substrcmp(*av, "set") == 0) 409 ipfw_sets_handler(av); 410 else if (_substrcmp(*av, "table") == 0) 411 ipfw_table_handler(ac, av); 412 else if (_substrcmp(*av, "enable") == 0) 413 ipfw_sysctl_handler(av, 1); 414 else if (_substrcmp(*av, "disable") == 0) 415 ipfw_sysctl_handler(av, 0); 416 else 417 try_next = 1; 418 } 419 420 if (co.use_set || try_next) { 421 if (_substrcmp(*av, "delete") == 0) 422 ipfw_delete(av); 423 else if (_substrcmp(*av, "flush") == 0) 424 ipfw_flush(co.do_force); 425 else if (_substrcmp(*av, "zero") == 0) 426 ipfw_zero(ac, av, 0 /* IP_FW_ZERO */); 427 else if (_substrcmp(*av, "resetlog") == 0) 428 ipfw_zero(ac, av, 1 /* IP_FW_RESETLOG */); 429 else if (_substrcmp(*av, "print") == 0 || 430 _substrcmp(*av, "list") == 0) 431 ipfw_list(ac, av, do_acct); 432 else if (_substrcmp(*av, "show") == 0) 433 ipfw_list(ac, av, 1 /* show counters */); 434 else 435 errx(EX_USAGE, "bad command `%s'", *av); 436 } 437 438 /* Free memory allocated in the argument parsing. */ 439 free(save_av); 440 return 0; 441} 442 443 444static void 445ipfw_readfile(int ac, char *av[]) 446{ 447#define MAX_ARGS 32 448 char buf[4096]; 449 char *progname = av[0]; /* original program name */ 450 const char *cmd = NULL; /* preprocessor name, if any */ 451 const char *filename = av[ac-1]; /* file to read */ 452 int c, lineno=0; 453 FILE *f = NULL; 454 pid_t preproc = 0; 455 456 while ((c = getopt(ac, av, "cfNnp:qS")) != -1) { 457 switch(c) { 458 case 'c': 459 co.do_compact = 1; 460 break; 461 462 case 'f': 463 co.do_force = 1; 464 break; 465 466 case 'N': 467 co.do_resolv = 1; 468 break; 469 470 case 'n': 471 co.test_only = 1; 472 break; 473 474 case 'p': 475 /* 476 * ipfw -p cmd [args] filename 477 * 478 * We are done with getopt(). All arguments 479 * except the filename go to the preprocessor, 480 * so we need to do the following: 481 * - check that a filename is actually present; 482 * - advance av by optind-1 to skip arguments 483 * already processed; 484 * - decrease ac by optind, to remove the args 485 * already processed and the final filename; 486 * - set the last entry in av[] to NULL so 487 * popen() can detect the end of the array; 488 * - set optind=ac to let getopt() terminate. 489 */ 490 if (optind == ac) 491 errx(EX_USAGE, "no filename argument"); 492 cmd = optarg; 493 av[ac-1] = NULL; 494 av += optind - 1; 495 ac -= optind; 496 optind = ac; 497 break; 498 499 case 'q': 500 co.do_quiet = 1; 501 break; 502 503 case 'S': 504 co.show_sets = 1; 505 break; 506 507 default: 508 errx(EX_USAGE, "bad arguments, for usage" 509 " summary ``ipfw''"); 510 } 511 512 } 513 514 if (cmd == NULL && ac != optind + 1) 515 errx(EX_USAGE, "extraneous filename arguments %s", av[ac-1]); 516 517 if ((f = fopen(filename, "r")) == NULL) 518 err(EX_UNAVAILABLE, "fopen: %s", filename); 519 520 if (cmd != NULL) { /* pipe through preprocessor */ 521 int pipedes[2]; 522 523 if (pipe(pipedes) == -1) 524 err(EX_OSERR, "cannot create pipe"); 525 526 preproc = fork(); 527 if (preproc == -1) 528 err(EX_OSERR, "cannot fork"); 529 530 if (preproc == 0) { 531 /* 532 * Child, will run the preprocessor with the 533 * file on stdin and the pipe on stdout. 534 */ 535 if (dup2(fileno(f), 0) == -1 536 || dup2(pipedes[1], 1) == -1) 537 err(EX_OSERR, "dup2()"); 538 fclose(f); 539 close(pipedes[1]); 540 close(pipedes[0]); 541 execvp(cmd, av); 542 err(EX_OSERR, "execvp(%s) failed", cmd); 543 } else { /* parent, will reopen f as the pipe */ 544 fclose(f); 545 close(pipedes[1]); 546 if ((f = fdopen(pipedes[0], "r")) == NULL) { 547 int savederrno = errno; 548 549 (void)kill(preproc, SIGTERM); 550 errno = savederrno; 551 err(EX_OSERR, "fdopen()"); 552 } 553 } 554 } 555 556 while (fgets(buf, sizeof(buf), f)) { /* read commands */ 557 char linename[20]; 558 char *args[2]; 559 560 lineno++; 561 snprintf(linename, sizeof(linename), "Line %d", lineno); 562 setprogname(linename); /* XXX */ 563 args[0] = progname; 564 args[1] = buf; 565 ipfw_main(2, args); 566 } 567 fclose(f); 568 if (cmd != NULL) { 569 int status; 570 571 if (waitpid(preproc, &status, 0) == -1) 572 errx(EX_OSERR, "waitpid()"); 573 if (WIFEXITED(status) && WEXITSTATUS(status) != EX_OK) 574 errx(EX_UNAVAILABLE, 575 "preprocessor exited with status %d", 576 WEXITSTATUS(status)); 577 else if (WIFSIGNALED(status)) 578 errx(EX_UNAVAILABLE, 579 "preprocessor exited with signal %d", 580 WTERMSIG(status)); 581 } 582} 583 584int 585main(int ac, char *av[]) 586{ 587#if defined(_WIN32) && defined(TCC) 588 { 589 WSADATA wsaData; 590 int ret=0; 591 unsigned short wVersionRequested = MAKEWORD(2, 2); 592 ret = WSAStartup(wVersionRequested, &wsaData); 593 if (ret != 0) { 594 /* Tell the user that we could not find a usable */ 595 /* Winsock DLL. */ 596 printf("WSAStartup failed with error: %d\n", ret); 597 return 1; 598 } 599 } 600#endif 601 /* 602 * If the last argument is an absolute pathname, interpret it 603 * as a file to be preprocessed. 604 */ 605 606 if (ac > 1 && av[ac - 1][0] == '/' && access(av[ac - 1], R_OK) == 0) 607 ipfw_readfile(ac, av); 608 else { 609 if (ipfw_main(ac, av)) { 610 errx(EX_USAGE, 611 "usage: ipfw [options]\n" 612 "do \"ipfw -h\" or \"man ipfw\" for details"); 613 } 614 } 615 return EX_OK; 616} 617