1 /* 2 * Copyright (c) 2002-2003 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 * $FreeBSD$ 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 36 static void 37 help(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 * Free a the (locally allocated) copy of command line arguments. 84 */ 85 static void 86 free_args(int ac, char **av) 87 { 88 int i; 89 90 for (i=0; i < ac; i++) 91 free(av[i]); 92 free(av); 93 } 94 95 /* 96 * Called with the arguments, including program name because getopt 97 * wants it to be present. 98 * Returns 0 if successful, 1 if empty command, errx() in case of errors. 99 */ 100 static int 101 ipfw_main(int oldac, char **oldav) 102 { 103 int ch, ac, save_ac; 104 const char *errstr; 105 char **av, **save_av; 106 int do_acct = 0; /* Show packet/byte count */ 107 int try_next = 0; /* set if pipe cmd not found */ 108 109 #define WHITESP " \t\f\v\n\r" 110 if (oldac < 2) 111 return 1; /* need at least one argument */ 112 113 if (oldac == 2) { 114 /* 115 * If we are called with a single string, try to split it into 116 * arguments for subsequent parsing. 117 * But first, remove spaces after a ',', by copying the string 118 * in-place. 119 */ 120 char *arg = oldav[1]; /* The string is the first arg. */ 121 int l = strlen(arg); 122 int copy = 0; /* 1 if we need to copy, 0 otherwise */ 123 int i, j; 124 125 for (i = j = 0; i < l; i++) { 126 if (arg[i] == '#') /* comment marker */ 127 break; 128 if (copy) { 129 arg[j++] = arg[i]; 130 copy = !index("," WHITESP, arg[i]); 131 } else { 132 copy = !index(WHITESP, arg[i]); 133 if (copy) 134 arg[j++] = arg[i]; 135 } 136 } 137 if (!copy && j > 0) /* last char was a 'blank', remove it */ 138 j--; 139 l = j; /* the new argument length */ 140 arg[j++] = '\0'; 141 if (l == 0) /* empty string! */ 142 return 1; 143 144 /* 145 * First, count number of arguments. Because of the previous 146 * processing, this is just the number of blanks plus 1. 147 */ 148 for (i = 0, ac = 1; i < l; i++) 149 if (index(WHITESP, arg[i]) != NULL) 150 ac++; 151 152 /* 153 * Allocate the argument list, including one entry for 154 * the program name because getopt expects it. 155 */ 156 av = safe_calloc(ac + 1, sizeof(char *)); 157 158 /* 159 * Second, copy arguments from arg[] to av[]. For each one, 160 * j is the initial character, i is the one past the end. 161 */ 162 for (ac = 1, i = j = 0; i < l; i++) 163 if (index(WHITESP, arg[i]) != NULL || i == l-1) { 164 if (i == l-1) 165 i++; 166 av[ac] = safe_calloc(i-j+1, 1); 167 bcopy(arg+j, av[ac], i-j); 168 ac++; 169 j = i + 1; 170 } 171 } else { 172 /* 173 * If an argument ends with ',' join with the next one. 174 */ 175 int first, i, l; 176 177 av = safe_calloc(oldac, sizeof(char *)); 178 for (first = i = ac = 1, l = 0; i < oldac; i++) { 179 char *arg = oldav[i]; 180 int k = strlen(arg); 181 182 l += k; 183 if (arg[k-1] != ',' || i == oldac-1) { 184 /* Time to copy. */ 185 av[ac] = safe_calloc(l+1, 1); 186 for (l=0; first <= i; first++) { 187 strcat(av[ac]+l, oldav[first]); 188 l += strlen(oldav[first]); 189 } 190 ac++; 191 l = 0; 192 first = i+1; 193 } 194 } 195 } 196 197 av[0] = strdup(oldav[0]); /* copy progname from the caller */ 198 /* Set the force flag for non-interactive processes */ 199 if (!co.do_force) 200 co.do_force = !isatty(STDIN_FILENO); 201 202 /* Save arguments for final freeing of memory. */ 203 save_ac = ac; 204 save_av = av; 205 206 optind = optreset = 1; /* restart getopt() */ 207 while ((ch = getopt(ac, av, "abcdefhinNqs:STtv")) != -1) 208 switch (ch) { 209 case 'a': 210 do_acct = 1; 211 break; 212 213 case 'b': 214 co.comment_only = 1; 215 co.do_compact = 1; 216 break; 217 218 case 'c': 219 co.do_compact = 1; 220 break; 221 222 case 'd': 223 co.do_dynamic = 1; 224 break; 225 226 case 'e': 227 co.do_expired = 1; 228 break; 229 230 case 'f': 231 co.do_force = 1; 232 break; 233 234 case 'h': /* help */ 235 free_args(save_ac, save_av); 236 help(); 237 break; /* NOTREACHED */ 238 239 case 'i': 240 co.do_value_as_ip = 1; 241 break; 242 243 case 'n': 244 co.test_only = 1; 245 break; 246 247 case 'N': 248 co.do_resolv = 1; 249 break; 250 251 case 'q': 252 co.do_quiet = 1; 253 break; 254 255 case 's': /* sort */ 256 co.do_sort = atoi(optarg); 257 break; 258 259 case 'S': 260 co.show_sets = 1; 261 break; 262 263 case 't': 264 co.do_time = 1; 265 break; 266 267 case 'T': 268 co.do_time = 2; /* numeric timestamp */ 269 break; 270 271 case 'v': /* verbose */ 272 co.verbose = 1; 273 break; 274 275 default: 276 free_args(save_ac, save_av); 277 return 1; 278 } 279 280 ac -= optind; 281 av += optind; 282 NEED1("bad arguments, for usage summary ``ipfw''"); 283 284 /* 285 * An undocumented behaviour of ipfw1 was to allow rule numbers first, 286 * e.g. "100 add allow ..." instead of "add 100 allow ...". 287 * In case, swap first and second argument to get the normal form. 288 */ 289 if (ac > 1 && isdigit(*av[0])) { 290 char *p = av[0]; 291 292 av[0] = av[1]; 293 av[1] = p; 294 } 295 296 /* 297 * Optional: pipe, queue or nat. 298 */ 299 co.do_nat = 0; 300 co.do_pipe = 0; 301 if (!strncmp(*av, "nat", strlen(*av))) 302 co.do_nat = 1; 303 else if (!strncmp(*av, "pipe", strlen(*av))) 304 co.do_pipe = 1; 305 else if (_substrcmp(*av, "queue") == 0) 306 co.do_pipe = 2; 307 else if (!strncmp(*av, "set", strlen(*av))) { 308 if (ac > 1 && isdigit(av[1][0])) { 309 co.use_set = strtonum(av[1], 0, resvd_set_number, 310 &errstr); 311 if (errstr) 312 errx(EX_DATAERR, 313 "invalid set number %s\n", av[1]); 314 ac -= 2; av += 2; co.use_set++; 315 } 316 } 317 318 if (co.do_pipe || co.do_nat) { 319 ac--; 320 av++; 321 } 322 NEED1("missing command"); 323 324 /* 325 * For pipes, queues and nats we normally say 'nat|pipe NN config' 326 * but the code is easier to parse as 'nat|pipe config NN' 327 * so we swap the two arguments. 328 */ 329 if ((co.do_pipe || co.do_nat) && ac > 1 && isdigit(*av[0])) { 330 char *p = av[0]; 331 332 av[0] = av[1]; 333 av[1] = p; 334 } 335 336 if (co.use_set == 0) { 337 if (_substrcmp(*av, "add") == 0) 338 ipfw_add(ac, av); 339 else if (co.do_nat && _substrcmp(*av, "show") == 0) 340 ipfw_show_nat(ac, av); 341 else if (co.do_pipe && _substrcmp(*av, "config") == 0) 342 ipfw_config_pipe(ac, av); 343 else if (co.do_nat && _substrcmp(*av, "config") == 0) 344 ipfw_config_nat(ac, av); 345 else if (_substrcmp(*av, "set") == 0) 346 ipfw_sets_handler(ac, av); 347 else if (_substrcmp(*av, "table") == 0) 348 ipfw_table_handler(ac, av); 349 else if (_substrcmp(*av, "enable") == 0) 350 ipfw_sysctl_handler(ac, av, 1); 351 else if (_substrcmp(*av, "disable") == 0) 352 ipfw_sysctl_handler(ac, av, 0); 353 else 354 try_next = 1; 355 } 356 357 if (co.use_set || try_next) { 358 if (_substrcmp(*av, "delete") == 0) 359 ipfw_delete(ac, av); 360 else if (_substrcmp(*av, "flush") == 0) 361 ipfw_flush(co.do_force); 362 else if (_substrcmp(*av, "zero") == 0) 363 ipfw_zero(ac, av, 0 /* IP_FW_ZERO */); 364 else if (_substrcmp(*av, "resetlog") == 0) 365 ipfw_zero(ac, av, 1 /* IP_FW_RESETLOG */); 366 else if (_substrcmp(*av, "print") == 0 || 367 _substrcmp(*av, "list") == 0) 368 ipfw_list(ac, av, do_acct); 369 else if (_substrcmp(*av, "show") == 0) 370 ipfw_list(ac, av, 1 /* show counters */); 371 else 372 errx(EX_USAGE, "bad command `%s'", *av); 373 } 374 375 /* Free memory allocated in the argument parsing. */ 376 free_args(save_ac, save_av); 377 return 0; 378 } 379 380 381 static void 382 ipfw_readfile(int ac, char *av[]) 383 { 384 #define MAX_ARGS 32 385 char buf[BUFSIZ]; 386 char *progname = av[0]; /* original program name */ 387 const char *cmd = NULL; /* preprocessor name, if any */ 388 const char *filename = av[ac-1]; /* file to read */ 389 int c, lineno=0; 390 FILE *f = NULL; 391 pid_t preproc = 0; 392 393 while ((c = getopt(ac, av, "cfNnp:qS")) != -1) { 394 switch(c) { 395 case 'c': 396 co.do_compact = 1; 397 break; 398 399 case 'f': 400 co.do_force = 1; 401 break; 402 403 case 'N': 404 co.do_resolv = 1; 405 break; 406 407 case 'n': 408 co.test_only = 1; 409 break; 410 411 case 'p': 412 /* 413 * ipfw -p cmd [args] filename 414 * 415 * We are done with getopt(). All arguments 416 * except the filename go to the preprocessor, 417 * so we need to do the following: 418 * - check that a filename is actually present; 419 * - advance av by optind-1 to skip arguments 420 * already processed; 421 * - decrease ac by optind, to remove the args 422 * already processed and the final filename; 423 * - set the last entry in av[] to NULL so 424 * popen() can detect the end of the array; 425 * - set optind=ac to let getopt() terminate. 426 */ 427 if (optind == ac) 428 errx(EX_USAGE, "no filename argument"); 429 cmd = optarg; 430 av[ac-1] = NULL; 431 av += optind - 1; 432 ac -= optind; 433 optind = ac; 434 break; 435 436 case 'q': 437 co.do_quiet = 1; 438 break; 439 440 case 'S': 441 co.show_sets = 1; 442 break; 443 444 default: 445 errx(EX_USAGE, "bad arguments, for usage" 446 " summary ``ipfw''"); 447 } 448 449 } 450 451 if (cmd == NULL && ac != optind + 1) 452 errx(EX_USAGE, "extraneous filename arguments %s", av[ac-1]); 453 454 if ((f = fopen(filename, "r")) == NULL) 455 err(EX_UNAVAILABLE, "fopen: %s", filename); 456 457 if (cmd != NULL) { /* pipe through preprocessor */ 458 int pipedes[2]; 459 460 if (pipe(pipedes) == -1) 461 err(EX_OSERR, "cannot create pipe"); 462 463 preproc = fork(); 464 if (preproc == -1) 465 err(EX_OSERR, "cannot fork"); 466 467 if (preproc == 0) { 468 /* 469 * Child, will run the preprocessor with the 470 * file on stdin and the pipe on stdout. 471 */ 472 if (dup2(fileno(f), 0) == -1 473 || dup2(pipedes[1], 1) == -1) 474 err(EX_OSERR, "dup2()"); 475 fclose(f); 476 close(pipedes[1]); 477 close(pipedes[0]); 478 execvp(cmd, av); 479 err(EX_OSERR, "execvp(%s) failed", cmd); 480 } else { /* parent, will reopen f as the pipe */ 481 fclose(f); 482 close(pipedes[1]); 483 if ((f = fdopen(pipedes[0], "r")) == NULL) { 484 int savederrno = errno; 485 486 (void)kill(preproc, SIGTERM); 487 errno = savederrno; 488 err(EX_OSERR, "fdopen()"); 489 } 490 } 491 } 492 493 while (fgets(buf, BUFSIZ, f)) { /* read commands */ 494 char linename[10]; 495 char *args[2]; 496 497 lineno++; 498 sprintf(linename, "Line %d", lineno); 499 setprogname(linename); /* XXX */ 500 args[0] = progname; 501 args[1] = buf; 502 ipfw_main(2, args); 503 } 504 fclose(f); 505 if (cmd != NULL) { 506 int status; 507 508 if (waitpid(preproc, &status, 0) == -1) 509 errx(EX_OSERR, "waitpid()"); 510 if (WIFEXITED(status) && WEXITSTATUS(status) != EX_OK) 511 errx(EX_UNAVAILABLE, 512 "preprocessor exited with status %d", 513 WEXITSTATUS(status)); 514 else if (WIFSIGNALED(status)) 515 errx(EX_UNAVAILABLE, 516 "preprocessor exited with signal %d", 517 WTERMSIG(status)); 518 } 519 } 520 521 int 522 main(int ac, char *av[]) 523 { 524 /* 525 * If the last argument is an absolute pathname, interpret it 526 * as a file to be preprocessed. 527 */ 528 529 if (ac > 1 && av[ac - 1][0] == '/' && access(av[ac - 1], R_OK) == 0) 530 ipfw_readfile(ac, av); 531 else { 532 if (ipfw_main(ac, av)) { 533 errx(EX_USAGE, 534 "usage: ipfw [options]\n" 535 "do \"ipfw -h\" or \"man ipfw\" for details"); 536 } 537 } 538 return EX_OK; 539 } 540