xtables.c revision f56b8a8bf4b1041cb875fd8439778f35276bdb30
1/* 2 * (C) 2000-2006 by the netfilter coreteam <coreteam@netfilter.org>: 3 * 4 * This program is free software; you can redistribute it and/or modify 5 * it under the terms of the GNU General Public License as published by 6 * the Free Software Foundation; either version 2 of the License, or 7 * (at your option) any later version. 8 * 9 * This program is distributed in the hope that it will be useful, 10 * but WITHOUT ANY WARRANTY; without even the implied warranty of 11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 12 * GNU General Public License for more details. 13 * 14 * You should have received a copy of the GNU General Public License 15 * along with this program; if not, write to the Free Software 16 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. 17 */ 18#include "config.h" 19#include <ctype.h> 20#include <errno.h> 21#include <fcntl.h> 22#include <inttypes.h> 23#include <netdb.h> 24#include <stdarg.h> 25#include <stdbool.h> 26#include <stdio.h> 27#include <stdlib.h> 28#include <string.h> 29#include <unistd.h> 30#include <sys/socket.h> 31#include <sys/stat.h> 32#include <sys/statfs.h> 33#include <sys/types.h> 34#include <sys/utsname.h> 35#include <sys/wait.h> 36#include <arpa/inet.h> 37#if defined(HAVE_LINUX_MAGIC_H) 38# include <linux/magic.h> /* for PROC_SUPER_MAGIC */ 39#elif defined(HAVE_LINUX_PROC_FS_H) 40# include <linux/proc_fs.h> /* Linux 2.4 */ 41#else 42# define PROC_SUPER_MAGIC 0x9fa0 43#endif 44 45#include <xtables.h> 46#include <limits.h> /* INT_MAX in ip_tables.h/ip6_tables.h */ 47#include <linux/netfilter_ipv4/ip_tables.h> 48#include <linux/netfilter_ipv6/ip6_tables.h> 49#include <libiptc/libxtc.h> 50 51#ifndef NO_SHARED_LIBS 52#include <dlfcn.h> 53#endif 54#ifndef IPT_SO_GET_REVISION_MATCH /* Old kernel source. */ 55# define IPT_SO_GET_REVISION_MATCH (IPT_BASE_CTL + 2) 56# define IPT_SO_GET_REVISION_TARGET (IPT_BASE_CTL + 3) 57#endif 58#ifndef IP6T_SO_GET_REVISION_MATCH /* Old kernel source. */ 59# define IP6T_SO_GET_REVISION_MATCH 68 60# define IP6T_SO_GET_REVISION_TARGET 69 61#endif 62#include <getopt.h> 63#include "iptables/internal.h" 64#include "xshared.h" 65 66#define NPROTO 255 67 68#ifndef PROC_SYS_MODPROBE 69#define PROC_SYS_MODPROBE "/proc/sys/kernel/modprobe" 70#endif 71 72/* we need this for ip6?tables-restore. ip6?tables-restore.c sets line to the 73 * current line of the input file, in order to give a more precise error 74 * message. ip6?tables itself doesn't need this, so it is initialized to the 75 * magic number of -1 */ 76int line = -1; 77 78void basic_exit_err(enum xtables_exittype status, const char *msg, ...) __attribute__((noreturn, format(printf,2,3))); 79 80struct xtables_globals *xt_params = NULL; 81 82void basic_exit_err(enum xtables_exittype status, const char *msg, ...) 83{ 84 va_list args; 85 86 va_start(args, msg); 87 fprintf(stderr, "%s v%s: ", xt_params->program_name, xt_params->program_version); 88 vfprintf(stderr, msg, args); 89 va_end(args); 90 fprintf(stderr, "\n"); 91 exit(status); 92} 93 94void xtables_free_opts(int unused) 95{ 96 if (xt_params->opts != xt_params->orig_opts) { 97 free(xt_params->opts); 98 xt_params->opts = NULL; 99 } 100} 101 102struct option *xtables_merge_options(struct option *orig_opts, 103 struct option *oldopts, 104 const struct option *newopts, 105 unsigned int *option_offset) 106{ 107 unsigned int num_oold = 0, num_old = 0, num_new = 0, i; 108 struct option *merge, *mp; 109 110 if (newopts == NULL) 111 return oldopts; 112 113 for (num_oold = 0; orig_opts[num_oold].name; num_oold++) ; 114 if (oldopts != NULL) 115 for (num_old = 0; oldopts[num_old].name; num_old++) ; 116 for (num_new = 0; newopts[num_new].name; num_new++) ; 117 118 /* 119 * Since @oldopts also has @orig_opts already (and does so at the 120 * start), skip these entries. 121 */ 122 oldopts += num_oold; 123 num_old -= num_oold; 124 125 merge = malloc(sizeof(*mp) * (num_oold + num_old + num_new + 1)); 126 if (merge == NULL) 127 return NULL; 128 129 /* Let the base options -[ADI...] have precedence over everything */ 130 memcpy(merge, orig_opts, sizeof(*mp) * num_oold); 131 mp = merge + num_oold; 132 133 /* Second, the new options */ 134 xt_params->option_offset += XT_OPTION_OFFSET_SCALE; 135 *option_offset = xt_params->option_offset; 136 memcpy(mp, newopts, sizeof(*mp) * num_new); 137 138 for (i = 0; i < num_new; ++i, ++mp) 139 mp->val += *option_offset; 140 141 /* Third, the old options */ 142 memcpy(mp, oldopts, sizeof(*mp) * num_old); 143 mp += num_old; 144 xtables_free_opts(0); 145 146 /* Clear trailing entry */ 147 memset(mp, 0, sizeof(*mp)); 148 return merge; 149} 150 151static const struct xtables_afinfo afinfo_ipv4 = { 152 .kmod = "ip_tables", 153 .proc_exists = "/proc/net/ip_tables_names", 154 .libprefix = "libipt_", 155 .family = NFPROTO_IPV4, 156 .ipproto = IPPROTO_IP, 157 .so_rev_match = IPT_SO_GET_REVISION_MATCH, 158 .so_rev_target = IPT_SO_GET_REVISION_TARGET, 159}; 160 161static const struct xtables_afinfo afinfo_ipv6 = { 162 .kmod = "ip6_tables", 163 .proc_exists = "/proc/net/ip6_tables_names", 164 .libprefix = "libip6t_", 165 .family = NFPROTO_IPV6, 166 .ipproto = IPPROTO_IPV6, 167 .so_rev_match = IP6T_SO_GET_REVISION_MATCH, 168 .so_rev_target = IP6T_SO_GET_REVISION_TARGET, 169}; 170 171const struct xtables_afinfo *afinfo; 172 173/* Search path for Xtables .so files */ 174static const char *xtables_libdir; 175 176/* the path to command to load kernel module */ 177const char *xtables_modprobe_program; 178 179/* Keep track of matches/targets pending full registration: linked lists. */ 180struct xtables_match *xtables_pending_matches; 181struct xtables_target *xtables_pending_targets; 182 183/* Keep track of fully registered external matches/targets: linked lists. */ 184struct xtables_match *xtables_matches; 185struct xtables_target *xtables_targets; 186 187/* Fully register a match/target which was previously partially registered. */ 188static void xtables_fully_register_pending_match(struct xtables_match *me); 189static void xtables_fully_register_pending_target(struct xtables_target *me); 190 191void xtables_init(void) 192{ 193 xtables_libdir = getenv("XTABLES_LIBDIR"); 194 if (xtables_libdir != NULL) 195 return; 196 xtables_libdir = getenv("IPTABLES_LIB_DIR"); 197 if (xtables_libdir != NULL) { 198 fprintf(stderr, "IPTABLES_LIB_DIR is deprecated, " 199 "use XTABLES_LIBDIR.\n"); 200 return; 201 } 202 /* 203 * Well yes, IP6TABLES_LIB_DIR is of lower priority over 204 * IPTABLES_LIB_DIR since this moved to libxtables; I think that is ok 205 * for these env vars are deprecated anyhow, and in light of the 206 * (shared) libxt_*.so files, makes less sense to have 207 * IPTABLES_LIB_DIR != IP6TABLES_LIB_DIR. 208 */ 209 xtables_libdir = getenv("IP6TABLES_LIB_DIR"); 210 if (xtables_libdir != NULL) { 211 fprintf(stderr, "IP6TABLES_LIB_DIR is deprecated, " 212 "use XTABLES_LIBDIR.\n"); 213 return; 214 } 215 xtables_libdir = XTABLES_LIBDIR; 216} 217 218void xtables_set_nfproto(uint8_t nfproto) 219{ 220 switch (nfproto) { 221 case NFPROTO_IPV4: 222 afinfo = &afinfo_ipv4; 223 break; 224 case NFPROTO_IPV6: 225 afinfo = &afinfo_ipv6; 226 break; 227 default: 228 fprintf(stderr, "libxtables: unhandled NFPROTO in %s\n", 229 __func__); 230 } 231} 232 233/** 234 * xtables_set_params - set the global parameters used by xtables 235 * @xtp: input xtables_globals structure 236 * 237 * The app is expected to pass a valid xtables_globals data-filled 238 * with proper values 239 * @xtp cannot be NULL 240 * 241 * Returns -1 on failure to set and 0 on success 242 */ 243int xtables_set_params(struct xtables_globals *xtp) 244{ 245 if (!xtp) { 246 fprintf(stderr, "%s: Illegal global params\n",__func__); 247 return -1; 248 } 249 250 xt_params = xtp; 251 252 if (!xt_params->exit_err) 253 xt_params->exit_err = basic_exit_err; 254 255 return 0; 256} 257 258int xtables_init_all(struct xtables_globals *xtp, uint8_t nfproto) 259{ 260 xtables_init(); 261 xtables_set_nfproto(nfproto); 262 return xtables_set_params(xtp); 263} 264 265/** 266 * xtables_*alloc - wrappers that exit on failure 267 */ 268void *xtables_calloc(size_t count, size_t size) 269{ 270 void *p; 271 272 if ((p = calloc(count, size)) == NULL) { 273 perror("ip[6]tables: calloc failed"); 274 exit(1); 275 } 276 277 return p; 278} 279 280void *xtables_malloc(size_t size) 281{ 282 void *p; 283 284 if ((p = malloc(size)) == NULL) { 285 perror("ip[6]tables: malloc failed"); 286 exit(1); 287 } 288 289 return p; 290} 291 292void *xtables_realloc(void *ptr, size_t size) 293{ 294 void *p; 295 296 if ((p = realloc(ptr, size)) == NULL) { 297 perror("ip[6]tables: realloc failed"); 298 exit(1); 299 } 300 301 return p; 302} 303 304static char *get_modprobe(void) 305{ 306 int procfile; 307 char *ret; 308 309#define PROCFILE_BUFSIZ 1024 310 procfile = open(PROC_SYS_MODPROBE, O_RDONLY); 311 if (procfile < 0) 312 return NULL; 313 if (fcntl(procfile, F_SETFD, FD_CLOEXEC) == -1) { 314 fprintf(stderr, "Could not set close on exec: %s\n", 315 strerror(errno)); 316 exit(1); 317 } 318 319 ret = malloc(PROCFILE_BUFSIZ); 320 if (ret) { 321 memset(ret, 0, PROCFILE_BUFSIZ); 322 switch (read(procfile, ret, PROCFILE_BUFSIZ)) { 323 case -1: goto fail; 324 case PROCFILE_BUFSIZ: goto fail; /* Partial read. Wierd */ 325 } 326 if (ret[strlen(ret)-1]=='\n') 327 ret[strlen(ret)-1]=0; 328 close(procfile); 329 return ret; 330 } 331 fail: 332 free(ret); 333 close(procfile); 334 return NULL; 335} 336 337int xtables_insmod(const char *modname, const char *modprobe, bool quiet) 338{ 339 char *buf = NULL; 340 char *argv[4]; 341 int status; 342 343 /* If they don't explicitly set it, read out of kernel */ 344 if (!modprobe) { 345 buf = get_modprobe(); 346 if (!buf) 347 return -1; 348 modprobe = buf; 349 } 350 351 /* 352 * Need to flush the buffer, or the child may output it again 353 * when switching the program thru execv. 354 */ 355 fflush(stdout); 356 357 switch (vfork()) { 358 case 0: 359 argv[0] = (char *)modprobe; 360 argv[1] = (char *)modname; 361 if (quiet) { 362 argv[2] = "-q"; 363 argv[3] = NULL; 364 } else { 365 argv[2] = NULL; 366 argv[3] = NULL; 367 } 368 execv(argv[0], argv); 369 370 /* not usually reached */ 371 exit(1); 372 case -1: 373 free(buf); 374 return -1; 375 376 default: /* parent */ 377 wait(&status); 378 } 379 380 free(buf); 381 if (WIFEXITED(status) && WEXITSTATUS(status) == 0) 382 return 0; 383 return -1; 384} 385 386/* return true if a given file exists within procfs */ 387static bool proc_file_exists(const char *filename) 388{ 389 struct stat s; 390 struct statfs f; 391 392 if (lstat(filename, &s)) 393 return false; 394 if (!S_ISREG(s.st_mode)) 395 return false; 396 if (statfs(filename, &f)) 397 return false; 398 if (f.f_type != PROC_SUPER_MAGIC) 399 return false; 400 return true; 401} 402 403int xtables_load_ko(const char *modprobe, bool quiet) 404{ 405 static bool loaded = false; 406 int ret; 407 408 if (loaded) 409 return 0; 410 411 if (proc_file_exists(afinfo->proc_exists)) { 412 loaded = true; 413 return 0; 414 }; 415 416 ret = xtables_insmod(afinfo->kmod, modprobe, quiet); 417 if (ret == 0) 418 loaded = true; 419 420 return ret; 421} 422 423/** 424 * xtables_strtou{i,l} - string to number conversion 425 * @s: input string 426 * @end: like strtoul's "end" pointer 427 * @value: pointer for result 428 * @min: minimum accepted value 429 * @max: maximum accepted value 430 * 431 * If @end is NULL, we assume the caller wants a "strict strtoul", and hence 432 * "15a" is rejected. 433 * In either case, the value obtained is compared for min-max compliance. 434 * Base is always 0, i.e. autodetect depending on @s. 435 * 436 * Returns true/false whether number was accepted. On failure, *value has 437 * undefined contents. 438 */ 439bool xtables_strtoul(const char *s, char **end, uintmax_t *value, 440 uintmax_t min, uintmax_t max) 441{ 442 uintmax_t v; 443 const char *p; 444 char *my_end; 445 446 errno = 0; 447 /* Since strtoul allows leading minus, we have to check for ourself. */ 448 for (p = s; isspace(*p); ++p) 449 ; 450 if (*p == '-') 451 return false; 452 v = strtoumax(s, &my_end, 0); 453 if (my_end == s) 454 return false; 455 if (end != NULL) 456 *end = my_end; 457 458 if (errno != ERANGE && min <= v && (max == 0 || v <= max)) { 459 if (value != NULL) 460 *value = v; 461 if (end == NULL) 462 return *my_end == '\0'; 463 return true; 464 } 465 466 return false; 467} 468 469bool xtables_strtoui(const char *s, char **end, unsigned int *value, 470 unsigned int min, unsigned int max) 471{ 472 uintmax_t v; 473 bool ret; 474 475 ret = xtables_strtoul(s, end, &v, min, max); 476 if (value != NULL) 477 *value = v; 478 return ret; 479} 480 481int xtables_service_to_port(const char *name, const char *proto) 482{ 483 struct servent *service; 484 485 if ((service = getservbyname(name, proto)) != NULL) 486 return ntohs((unsigned short) service->s_port); 487 488 return -1; 489} 490 491uint16_t xtables_parse_port(const char *port, const char *proto) 492{ 493 unsigned int portnum; 494 495 if (xtables_strtoui(port, NULL, &portnum, 0, UINT16_MAX) || 496 (portnum = xtables_service_to_port(port, proto)) != (unsigned)-1) 497 return portnum; 498 499 xt_params->exit_err(PARAMETER_PROBLEM, 500 "invalid port/service `%s' specified", port); 501} 502 503void xtables_parse_interface(const char *arg, char *vianame, 504 unsigned char *mask) 505{ 506 unsigned int vialen = strlen(arg); 507 unsigned int i; 508 509 memset(mask, 0, IFNAMSIZ); 510 memset(vianame, 0, IFNAMSIZ); 511 512 if (vialen + 1 > IFNAMSIZ) 513 xt_params->exit_err(PARAMETER_PROBLEM, 514 "interface name `%s' must be shorter than IFNAMSIZ" 515 " (%i)", arg, IFNAMSIZ-1); 516 517 strcpy(vianame, arg); 518 if (vialen == 0) 519 return; 520 else if (vianame[vialen - 1] == '+') { 521 memset(mask, 0xFF, vialen - 1); 522 /* Don't remove `+' here! -HW */ 523 } else { 524 /* Include nul-terminator in match */ 525 memset(mask, 0xFF, vialen + 1); 526 for (i = 0; vianame[i]; i++) { 527 if (vianame[i] == '/' || 528 vianame[i] == ' ') { 529 fprintf(stderr, 530 "Warning: weird character in interface" 531 " `%s' ('/' and ' ' are not allowed by the kernel).\n", 532 vianame); 533 break; 534 } 535 } 536 } 537} 538 539#ifndef NO_SHARED_LIBS 540static void *load_extension(const char *search_path, const char *af_prefix, 541 const char *name, bool is_target) 542{ 543 const char *all_prefixes[] = {"libxt_", af_prefix, NULL}; 544 const char **prefix; 545 const char *dir = search_path, *next; 546 void *ptr = NULL; 547 struct stat sb; 548 char path[256]; 549 550 do { 551 next = strchr(dir, ':'); 552 if (next == NULL) 553 next = dir + strlen(dir); 554 555 for (prefix = all_prefixes; *prefix != NULL; ++prefix) { 556 snprintf(path, sizeof(path), "%.*s/%s%s.so", 557 (unsigned int)(next - dir), dir, 558 *prefix, name); 559 560 if (stat(path, &sb) != 0) { 561 if (errno == ENOENT) 562 continue; 563 fprintf(stderr, "%s: %s\n", path, 564 strerror(errno)); 565 return NULL; 566 } 567 if (dlopen(path, RTLD_NOW) == NULL) { 568 fprintf(stderr, "%s: %s\n", path, dlerror()); 569 break; 570 } 571 572 if (is_target) 573 ptr = xtables_find_target(name, XTF_DONT_LOAD); 574 else 575 ptr = xtables_find_match(name, 576 XTF_DONT_LOAD, NULL); 577 578 if (ptr != NULL) 579 return ptr; 580 581 fprintf(stderr, "%s: no \"%s\" extension found for " 582 "this protocol\n", path, name); 583 errno = ENOENT; 584 return NULL; 585 } 586 dir = next + 1; 587 } while (*next != '\0'); 588 589 return NULL; 590} 591#endif 592 593struct xtables_match * 594xtables_find_match(const char *name, enum xtables_tryload tryload, 595 struct xtables_rule_match **matches) 596{ 597 struct xtables_match **dptr; 598 struct xtables_match *ptr; 599 const char *icmp6 = "icmp6"; 600 601 if (strlen(name) >= XT_EXTENSION_MAXNAMELEN) 602 xtables_error(PARAMETER_PROBLEM, 603 "Invalid match name \"%s\" (%u chars max)", 604 name, XT_EXTENSION_MAXNAMELEN - 1); 605 606 /* This is ugly as hell. Nonetheless, there is no way of changing 607 * this without hurting backwards compatibility */ 608 if ( (strcmp(name,"icmpv6") == 0) || 609 (strcmp(name,"ipv6-icmp") == 0) || 610 (strcmp(name,"icmp6") == 0) ) 611 name = icmp6; 612 613 /* Trigger delayed initialization */ 614 for (dptr = &xtables_pending_matches; *dptr; ) { 615 if (strcmp(name, (*dptr)->name) == 0) { 616 ptr = *dptr; 617 *dptr = (*dptr)->next; 618 ptr->next = NULL; 619 xtables_fully_register_pending_match(ptr); 620 } else { 621 dptr = &((*dptr)->next); 622 } 623 } 624 625 for (ptr = xtables_matches; ptr; ptr = ptr->next) { 626 if (strcmp(name, ptr->name) == 0) { 627 struct xtables_match *clone; 628 629 /* First match of this type: */ 630 if (ptr->m == NULL) 631 break; 632 633 /* Second and subsequent clones */ 634 clone = xtables_malloc(sizeof(struct xtables_match)); 635 memcpy(clone, ptr, sizeof(struct xtables_match)); 636 clone->udata = NULL; 637 clone->mflags = 0; 638 /* This is a clone: */ 639 clone->next = clone; 640 641 ptr = clone; 642 break; 643 } 644 } 645 646#ifndef NO_SHARED_LIBS 647 if (!ptr && tryload != XTF_DONT_LOAD && tryload != XTF_DURING_LOAD) { 648 ptr = load_extension(xtables_libdir, afinfo->libprefix, 649 name, false); 650 651 if (ptr == NULL && tryload == XTF_LOAD_MUST_SUCCEED) 652 xt_params->exit_err(PARAMETER_PROBLEM, 653 "Couldn't load match `%s':%s\n", 654 name, strerror(errno)); 655 } 656#else 657 if (ptr && !ptr->loaded) { 658 if (tryload != XTF_DONT_LOAD) 659 ptr->loaded = 1; 660 else 661 ptr = NULL; 662 } 663 if(!ptr && (tryload == XTF_LOAD_MUST_SUCCEED)) { 664 xt_params->exit_err(PARAMETER_PROBLEM, 665 "Couldn't find match `%s'\n", name); 666 } 667#endif 668 669 if (ptr && matches) { 670 struct xtables_rule_match **i; 671 struct xtables_rule_match *newentry; 672 673 newentry = xtables_malloc(sizeof(struct xtables_rule_match)); 674 675 for (i = matches; *i; i = &(*i)->next) { 676 if (strcmp(name, (*i)->match->name) == 0) 677 (*i)->completed = true; 678 } 679 newentry->match = ptr; 680 newentry->completed = false; 681 newentry->next = NULL; 682 *i = newentry; 683 } 684 685 return ptr; 686} 687 688struct xtables_target * 689xtables_find_target(const char *name, enum xtables_tryload tryload) 690{ 691 struct xtables_target **dptr; 692 struct xtables_target *ptr; 693 694 /* Standard target? */ 695 if (strcmp(name, "") == 0 696 || strcmp(name, XTC_LABEL_ACCEPT) == 0 697 || strcmp(name, XTC_LABEL_DROP) == 0 698 || strcmp(name, XTC_LABEL_QUEUE) == 0 699 || strcmp(name, XTC_LABEL_RETURN) == 0) 700 name = "standard"; 701 702 /* Trigger delayed initialization */ 703 for (dptr = &xtables_pending_targets; *dptr; ) { 704 if (strcmp(name, (*dptr)->name) == 0) { 705 ptr = *dptr; 706 *dptr = (*dptr)->next; 707 ptr->next = NULL; 708 xtables_fully_register_pending_target(ptr); 709 } else { 710 dptr = &((*dptr)->next); 711 } 712 } 713 714 for (ptr = xtables_targets; ptr; ptr = ptr->next) { 715 if (strcmp(name, ptr->name) == 0) 716 break; 717 } 718 719#ifndef NO_SHARED_LIBS 720 if (!ptr && tryload != XTF_DONT_LOAD && tryload != XTF_DURING_LOAD) { 721 ptr = load_extension(xtables_libdir, afinfo->libprefix, 722 name, true); 723 724 if (ptr == NULL && tryload == XTF_LOAD_MUST_SUCCEED) 725 xt_params->exit_err(PARAMETER_PROBLEM, 726 "Couldn't load target `%s':%s\n", 727 name, strerror(errno)); 728 } 729#else 730 if (ptr && !ptr->loaded) { 731 if (tryload != XTF_DONT_LOAD) 732 ptr->loaded = 1; 733 else 734 ptr = NULL; 735 } 736 if (ptr == NULL && tryload == XTF_LOAD_MUST_SUCCEED) { 737 xt_params->exit_err(PARAMETER_PROBLEM, 738 "Couldn't find target `%s'\n", name); 739 } 740#endif 741 742 if (ptr) 743 ptr->used = 1; 744 745 return ptr; 746} 747 748static int compatible_revision(const char *name, uint8_t revision, int opt) 749{ 750 struct xt_get_revision rev; 751 socklen_t s = sizeof(rev); 752 int max_rev, sockfd; 753 754 sockfd = socket(afinfo->family, SOCK_RAW, IPPROTO_RAW); 755 if (sockfd < 0) { 756 if (errno == EPERM) { 757 /* revision 0 is always supported. */ 758 if (revision != 0) 759 fprintf(stderr, "%s: Could not determine whether " 760 "revision %u is supported, " 761 "assuming it is.\n", 762 name, revision); 763 return 1; 764 } 765 fprintf(stderr, "Could not open socket to kernel: %s\n", 766 strerror(errno)); 767 exit(1); 768 } 769 770 if (fcntl(sockfd, F_SETFD, FD_CLOEXEC) == -1) { 771 fprintf(stderr, "Could not set close on exec: %s\n", 772 strerror(errno)); 773 exit(1); 774 } 775 776 xtables_load_ko(xtables_modprobe_program, true); 777 778 strcpy(rev.name, name); 779 rev.revision = revision; 780 781 max_rev = getsockopt(sockfd, afinfo->ipproto, opt, &rev, &s); 782 if (max_rev < 0) { 783 /* Definitely don't support this? */ 784 if (errno == ENOENT || errno == EPROTONOSUPPORT) { 785 close(sockfd); 786 return 0; 787 } else if (errno == ENOPROTOOPT) { 788 close(sockfd); 789 /* Assume only revision 0 support (old kernel) */ 790 return (revision == 0); 791 } else { 792 fprintf(stderr, "getsockopt failed strangely: %s\n", 793 strerror(errno)); 794 exit(1); 795 } 796 } 797 close(sockfd); 798 return 1; 799} 800 801 802static int compatible_match_revision(const char *name, uint8_t revision) 803{ 804 return compatible_revision(name, revision, afinfo->so_rev_match); 805} 806 807static int compatible_target_revision(const char *name, uint8_t revision) 808{ 809 return compatible_revision(name, revision, afinfo->so_rev_target); 810} 811 812static void xtables_check_options(const char *name, const struct option *opt) 813{ 814 for (; opt->name != NULL; ++opt) 815 if (opt->val < 0 || opt->val >= XT_OPTION_OFFSET_SCALE) { 816 fprintf(stderr, "%s: Extension %s uses invalid " 817 "option value %d\n",xt_params->program_name, 818 name, opt->val); 819 exit(1); 820 } 821} 822 823void xtables_register_match(struct xtables_match *me) 824{ 825 if (me->version == NULL) { 826 fprintf(stderr, "%s: match %s<%u> is missing a version\n", 827 xt_params->program_name, me->name, me->revision); 828 exit(1); 829 } 830 if (strcmp(me->version, XTABLES_VERSION) != 0) { 831 fprintf(stderr, "%s: match \"%s\" has version \"%s\", " 832 "but \"%s\" is required.\n", 833 xt_params->program_name, me->name, 834 me->version, XTABLES_VERSION); 835 exit(1); 836 } 837 838 if (strlen(me->name) >= XT_EXTENSION_MAXNAMELEN) { 839 fprintf(stderr, "%s: match `%s' has invalid name\n", 840 xt_params->program_name, me->name); 841 exit(1); 842 } 843 844 if (me->family >= NPROTO) { 845 fprintf(stderr, 846 "%s: BUG: match %s has invalid protocol family\n", 847 xt_params->program_name, me->name); 848 exit(1); 849 } 850 851 if (me->x6_options != NULL) 852 xtables_option_metavalidate(me->name, me->x6_options); 853 if (me->extra_opts != NULL) 854 xtables_check_options(me->name, me->extra_opts); 855 856 /* ignore not interested match */ 857 if (me->family != afinfo->family && me->family != AF_UNSPEC) 858 return; 859 860 /* place on linked list of matches pending full registration */ 861 me->next = xtables_pending_matches; 862 xtables_pending_matches = me; 863} 864 865static void xtables_fully_register_pending_match(struct xtables_match *me) 866{ 867 struct xtables_match **i, *old; 868 869 old = xtables_find_match(me->name, XTF_DURING_LOAD, NULL); 870 if (old) { 871 if (old->revision == me->revision && 872 old->family == me->family) { 873 fprintf(stderr, 874 "%s: match `%s' already registered.\n", 875 xt_params->program_name, me->name); 876 exit(1); 877 } 878 879 /* Now we have two (or more) options, check compatibility. */ 880 if (compatible_match_revision(old->name, old->revision) 881 && old->revision > me->revision) 882 return; 883 884 /* See if new match can be used. */ 885 if (!compatible_match_revision(me->name, me->revision)) 886 return; 887 888 /* Prefer !AF_UNSPEC over AF_UNSPEC for same revision. */ 889 if (old->revision == me->revision && me->family == AF_UNSPEC) 890 return; 891 892 /* Delete old one. */ 893 for (i = &xtables_matches; *i!=old; i = &(*i)->next); 894 *i = old->next; 895 } 896 897 if (me->size != XT_ALIGN(me->size)) { 898 fprintf(stderr, "%s: match `%s' has invalid size %u.\n", 899 xt_params->program_name, me->name, 900 (unsigned int)me->size); 901 exit(1); 902 } 903 904 /* Append to list. */ 905 for (i = &xtables_matches; *i; i = &(*i)->next); 906 me->next = NULL; 907 *i = me; 908 909 me->m = NULL; 910 me->mflags = 0; 911} 912 913void xtables_register_matches(struct xtables_match *match, unsigned int n) 914{ 915 do { 916 xtables_register_match(&match[--n]); 917 } while (n > 0); 918} 919 920void xtables_register_target(struct xtables_target *me) 921{ 922 if (me->version == NULL) { 923 fprintf(stderr, "%s: target %s<%u> is missing a version\n", 924 xt_params->program_name, me->name, me->revision); 925 exit(1); 926 } 927 if (strcmp(me->version, XTABLES_VERSION) != 0) { 928 fprintf(stderr, "%s: target \"%s\" has version \"%s\", " 929 "but \"%s\" is required.\n", 930 xt_params->program_name, me->name, 931 me->version, XTABLES_VERSION); 932 exit(1); 933 } 934 935 if (strlen(me->name) >= XT_EXTENSION_MAXNAMELEN) { 936 fprintf(stderr, "%s: target `%s' has invalid name\n", 937 xt_params->program_name, me->name); 938 exit(1); 939 } 940 941 if (me->family >= NPROTO) { 942 fprintf(stderr, 943 "%s: BUG: target %s has invalid protocol family\n", 944 xt_params->program_name, me->name); 945 exit(1); 946 } 947 948 if (me->x6_options != NULL) 949 xtables_option_metavalidate(me->name, me->x6_options); 950 if (me->extra_opts != NULL) 951 xtables_check_options(me->name, me->extra_opts); 952 953 /* ignore not interested target */ 954 if (me->family != afinfo->family && me->family != AF_UNSPEC) 955 return; 956 957 /* place on linked list of targets pending full registration */ 958 me->next = xtables_pending_targets; 959 xtables_pending_targets = me; 960} 961 962static void xtables_fully_register_pending_target(struct xtables_target *me) 963{ 964 struct xtables_target *old; 965 966 old = xtables_find_target(me->name, XTF_DURING_LOAD); 967 if (old) { 968 struct xtables_target **i; 969 970 if (old->revision == me->revision && 971 old->family == me->family) { 972 fprintf(stderr, 973 "%s: target `%s' already registered.\n", 974 xt_params->program_name, me->name); 975 exit(1); 976 } 977 978 /* Now we have two (or more) options, check compatibility. */ 979 if (compatible_target_revision(old->name, old->revision) 980 && old->revision > me->revision) 981 return; 982 983 /* See if new target can be used. */ 984 if (!compatible_target_revision(me->name, me->revision)) 985 return; 986 987 /* Prefer !AF_UNSPEC over AF_UNSPEC for same revision. */ 988 if (old->revision == me->revision && me->family == AF_UNSPEC) 989 return; 990 991 /* Delete old one. */ 992 for (i = &xtables_targets; *i!=old; i = &(*i)->next); 993 *i = old->next; 994 } 995 996 if (me->size != XT_ALIGN(me->size)) { 997 fprintf(stderr, "%s: target `%s' has invalid size %u.\n", 998 xt_params->program_name, me->name, 999 (unsigned int)me->size); 1000 exit(1); 1001 } 1002 1003 /* Prepend to list. */ 1004 me->next = xtables_targets; 1005 xtables_targets = me; 1006 me->t = NULL; 1007 me->tflags = 0; 1008} 1009 1010void xtables_register_targets(struct xtables_target *target, unsigned int n) 1011{ 1012 do { 1013 xtables_register_target(&target[--n]); 1014 } while (n > 0); 1015} 1016 1017/** 1018 * xtables_param_act - act on condition 1019 * @status: a constant from enum xtables_exittype 1020 * 1021 * %XTF_ONLY_ONCE: print error message that option may only be used once. 1022 * @p1: module name (e.g. "mark") 1023 * @p2(...): option in conflict (e.g. "--mark") 1024 * @p3(...): condition to match on (see extensions/ for examples) 1025 * 1026 * %XTF_NO_INVERT: option does not support inversion 1027 * @p1: module name 1028 * @p2: option in conflict 1029 * @p3: condition to match on 1030 * 1031 * %XTF_BAD_VALUE: bad value for option 1032 * @p1: module name 1033 * @p2: option with which the problem occured (e.g. "--mark") 1034 * @p3: string the user passed in (e.g. "99999999999999") 1035 * 1036 * %XTF_ONE_ACTION: two mutually exclusive actions have been specified 1037 * @p1: module name 1038 * 1039 * Displays an error message and exits the program. 1040 */ 1041void xtables_param_act(unsigned int status, const char *p1, ...) 1042{ 1043 const char *p2, *p3; 1044 va_list args; 1045 bool b; 1046 1047 va_start(args, p1); 1048 1049 switch (status) { 1050 case XTF_ONLY_ONCE: 1051 p2 = va_arg(args, const char *); 1052 b = va_arg(args, unsigned int); 1053 if (!b) { 1054 va_end(args); 1055 return; 1056 } 1057 xt_params->exit_err(PARAMETER_PROBLEM, 1058 "%s: \"%s\" option may only be specified once", 1059 p1, p2); 1060 break; 1061 case XTF_NO_INVERT: 1062 p2 = va_arg(args, const char *); 1063 b = va_arg(args, unsigned int); 1064 if (!b) { 1065 va_end(args); 1066 return; 1067 } 1068 xt_params->exit_err(PARAMETER_PROBLEM, 1069 "%s: \"%s\" option cannot be inverted", p1, p2); 1070 break; 1071 case XTF_BAD_VALUE: 1072 p2 = va_arg(args, const char *); 1073 p3 = va_arg(args, const char *); 1074 xt_params->exit_err(PARAMETER_PROBLEM, 1075 "%s: Bad value for \"%s\" option: \"%s\"", 1076 p1, p2, p3); 1077 break; 1078 case XTF_ONE_ACTION: 1079 b = va_arg(args, unsigned int); 1080 if (!b) { 1081 va_end(args); 1082 return; 1083 } 1084 xt_params->exit_err(PARAMETER_PROBLEM, 1085 "%s: At most one action is possible", p1); 1086 break; 1087 default: 1088 xt_params->exit_err(status, p1, args); 1089 break; 1090 } 1091 1092 va_end(args); 1093} 1094 1095const char *xtables_ipaddr_to_numeric(const struct in_addr *addrp) 1096{ 1097 static char buf[20]; 1098 const unsigned char *bytep = (const void *)&addrp->s_addr; 1099 1100 sprintf(buf, "%u.%u.%u.%u", bytep[0], bytep[1], bytep[2], bytep[3]); 1101 return buf; 1102} 1103 1104static const char *ipaddr_to_host(const struct in_addr *addr) 1105{ 1106 struct hostent *host; 1107 1108 host = gethostbyaddr(addr, sizeof(struct in_addr), AF_INET); 1109 if (host == NULL) 1110 return NULL; 1111 1112 return host->h_name; 1113} 1114 1115static const char *ipaddr_to_network(const struct in_addr *addr) 1116{ 1117 struct netent *net; 1118 1119 if ((net = getnetbyaddr(ntohl(addr->s_addr), AF_INET)) != NULL) 1120 return net->n_name; 1121 1122 return NULL; 1123} 1124 1125const char *xtables_ipaddr_to_anyname(const struct in_addr *addr) 1126{ 1127 const char *name; 1128 1129 if ((name = ipaddr_to_host(addr)) != NULL || 1130 (name = ipaddr_to_network(addr)) != NULL) 1131 return name; 1132 1133 return xtables_ipaddr_to_numeric(addr); 1134} 1135 1136const char *xtables_ipmask_to_numeric(const struct in_addr *mask) 1137{ 1138 static char buf[20]; 1139 uint32_t maskaddr, bits; 1140 int i; 1141 1142 maskaddr = ntohl(mask->s_addr); 1143 1144 if (maskaddr == 0xFFFFFFFFL) 1145 /* we don't want to see "/32" */ 1146 return ""; 1147 1148 i = 32; 1149 bits = 0xFFFFFFFEL; 1150 while (--i >= 0 && maskaddr != bits) 1151 bits <<= 1; 1152 if (i >= 0) 1153 sprintf(buf, "/%d", i); 1154 else 1155 /* mask was not a decent combination of 1's and 0's */ 1156 sprintf(buf, "/%s", xtables_ipaddr_to_numeric(mask)); 1157 1158 return buf; 1159} 1160 1161static struct in_addr *__numeric_to_ipaddr(const char *dotted, bool is_mask) 1162{ 1163 static struct in_addr addr; 1164 unsigned char *addrp; 1165 unsigned int onebyte; 1166 char buf[20], *p, *q; 1167 int i; 1168 1169 /* copy dotted string, because we need to modify it */ 1170 strncpy(buf, dotted, sizeof(buf) - 1); 1171 buf[sizeof(buf) - 1] = '\0'; 1172 addrp = (void *)&addr.s_addr; 1173 1174 p = buf; 1175 for (i = 0; i < 3; ++i) { 1176 if ((q = strchr(p, '.')) == NULL) { 1177 if (is_mask) 1178 return NULL; 1179 1180 /* autocomplete, this is a network address */ 1181 if (!xtables_strtoui(p, NULL, &onebyte, 0, UINT8_MAX)) 1182 return NULL; 1183 1184 addrp[i] = onebyte; 1185 while (i < 3) 1186 addrp[++i] = 0; 1187 1188 return &addr; 1189 } 1190 1191 *q = '\0'; 1192 if (!xtables_strtoui(p, NULL, &onebyte, 0, UINT8_MAX)) 1193 return NULL; 1194 1195 addrp[i] = onebyte; 1196 p = q + 1; 1197 } 1198 1199 /* we have checked 3 bytes, now we check the last one */ 1200 if (!xtables_strtoui(p, NULL, &onebyte, 0, UINT8_MAX)) 1201 return NULL; 1202 1203 addrp[3] = onebyte; 1204 return &addr; 1205} 1206 1207struct in_addr *xtables_numeric_to_ipaddr(const char *dotted) 1208{ 1209 return __numeric_to_ipaddr(dotted, false); 1210} 1211 1212struct in_addr *xtables_numeric_to_ipmask(const char *dotted) 1213{ 1214 return __numeric_to_ipaddr(dotted, true); 1215} 1216 1217static struct in_addr *network_to_ipaddr(const char *name) 1218{ 1219 static struct in_addr addr; 1220 struct netent *net; 1221 1222 if ((net = getnetbyname(name)) != NULL) { 1223 if (net->n_addrtype != AF_INET) 1224 return NULL; 1225 addr.s_addr = htonl(net->n_net); 1226 return &addr; 1227 } 1228 1229 return NULL; 1230} 1231 1232static struct in_addr *host_to_ipaddr(const char *name, unsigned int *naddr) 1233{ 1234 struct hostent *host; 1235 struct in_addr *addr; 1236 unsigned int i; 1237 1238 *naddr = 0; 1239 if ((host = gethostbyname(name)) != NULL) { 1240 if (host->h_addrtype != AF_INET || 1241 host->h_length != sizeof(struct in_addr)) 1242 return NULL; 1243 1244 while (host->h_addr_list[*naddr] != NULL) 1245 ++*naddr; 1246 addr = xtables_calloc(*naddr, sizeof(struct in_addr)); 1247 for (i = 0; i < *naddr; i++) 1248 memcpy(&addr[i], host->h_addr_list[i], 1249 sizeof(struct in_addr)); 1250 return addr; 1251 } 1252 1253 return NULL; 1254} 1255 1256static struct in_addr * 1257ipparse_hostnetwork(const char *name, unsigned int *naddrs) 1258{ 1259 struct in_addr *addrptmp, *addrp; 1260 1261 if ((addrptmp = xtables_numeric_to_ipaddr(name)) != NULL || 1262 (addrptmp = network_to_ipaddr(name)) != NULL) { 1263 addrp = xtables_malloc(sizeof(struct in_addr)); 1264 memcpy(addrp, addrptmp, sizeof(*addrp)); 1265 *naddrs = 1; 1266 return addrp; 1267 } 1268 if ((addrptmp = host_to_ipaddr(name, naddrs)) != NULL) 1269 return addrptmp; 1270 1271 xt_params->exit_err(PARAMETER_PROBLEM, "host/network `%s' not found", name); 1272} 1273 1274static struct in_addr *parse_ipmask(const char *mask) 1275{ 1276 static struct in_addr maskaddr; 1277 struct in_addr *addrp; 1278 unsigned int bits; 1279 1280 if (mask == NULL) { 1281 /* no mask at all defaults to 32 bits */ 1282 maskaddr.s_addr = 0xFFFFFFFF; 1283 return &maskaddr; 1284 } 1285 if ((addrp = xtables_numeric_to_ipmask(mask)) != NULL) 1286 /* dotted_to_addr already returns a network byte order addr */ 1287 return addrp; 1288 if (!xtables_strtoui(mask, NULL, &bits, 0, 32)) 1289 xt_params->exit_err(PARAMETER_PROBLEM, 1290 "invalid mask `%s' specified", mask); 1291 if (bits != 0) { 1292 maskaddr.s_addr = htonl(0xFFFFFFFF << (32 - bits)); 1293 return &maskaddr; 1294 } 1295 1296 maskaddr.s_addr = 0U; 1297 return &maskaddr; 1298} 1299 1300void xtables_ipparse_multiple(const char *name, struct in_addr **addrpp, 1301 struct in_addr **maskpp, unsigned int *naddrs) 1302{ 1303 struct in_addr *addrp; 1304 char buf[256], *p, *next; 1305 unsigned int len, i, j, n, count = 1; 1306 const char *loop = name; 1307 1308 while ((loop = strchr(loop, ',')) != NULL) { 1309 ++count; 1310 ++loop; /* skip ',' */ 1311 } 1312 1313 *addrpp = xtables_malloc(sizeof(struct in_addr) * count); 1314 *maskpp = xtables_malloc(sizeof(struct in_addr) * count); 1315 1316 loop = name; 1317 1318 for (i = 0; i < count; ++i) { 1319 while (isspace(*loop)) 1320 ++loop; 1321 next = strchr(loop, ','); 1322 if (next != NULL) 1323 len = next - loop; 1324 else 1325 len = strlen(loop); 1326 if (len > sizeof(buf) - 1) 1327 xt_params->exit_err(PARAMETER_PROBLEM, 1328 "Hostname too long"); 1329 1330 strncpy(buf, loop, len); 1331 buf[len] = '\0'; 1332 if ((p = strrchr(buf, '/')) != NULL) { 1333 *p = '\0'; 1334 addrp = parse_ipmask(p + 1); 1335 } else { 1336 addrp = parse_ipmask(NULL); 1337 } 1338 memcpy(*maskpp + i, addrp, sizeof(*addrp)); 1339 1340 /* if a null mask is given, the name is ignored, like in "any/0" */ 1341 if ((*maskpp + i)->s_addr == 0) 1342 /* 1343 * A bit pointless to process multiple addresses 1344 * in this case... 1345 */ 1346 strcpy(buf, "0.0.0.0"); 1347 1348 addrp = ipparse_hostnetwork(buf, &n); 1349 if (n > 1) { 1350 count += n - 1; 1351 *addrpp = xtables_realloc(*addrpp, 1352 sizeof(struct in_addr) * count); 1353 *maskpp = xtables_realloc(*maskpp, 1354 sizeof(struct in_addr) * count); 1355 for (j = 0; j < n; ++j) 1356 /* for each new addr */ 1357 memcpy(*addrpp + i + j, addrp + j, 1358 sizeof(*addrp)); 1359 for (j = 1; j < n; ++j) 1360 /* for each new mask */ 1361 memcpy(*maskpp + i + j, *maskpp + i, 1362 sizeof(*addrp)); 1363 i += n - 1; 1364 } else { 1365 memcpy(*addrpp + i, addrp, sizeof(*addrp)); 1366 } 1367 /* free what ipparse_hostnetwork had allocated: */ 1368 free(addrp); 1369 if (next == NULL) 1370 break; 1371 loop = next + 1; 1372 } 1373 *naddrs = count; 1374 for (i = 0; i < count; ++i) 1375 (*addrpp+i)->s_addr &= (*maskpp+i)->s_addr; 1376} 1377 1378 1379/** 1380 * xtables_ipparse_any - transform arbitrary name to in_addr 1381 * 1382 * Possible inputs (pseudo regex): 1383 * m{^($hostname|$networkname|$ipaddr)(/$mask)?} 1384 * "1.2.3.4/5", "1.2.3.4", "hostname", "networkname" 1385 */ 1386void xtables_ipparse_any(const char *name, struct in_addr **addrpp, 1387 struct in_addr *maskp, unsigned int *naddrs) 1388{ 1389 unsigned int i, j, k, n; 1390 struct in_addr *addrp; 1391 char buf[256], *p; 1392 1393 strncpy(buf, name, sizeof(buf) - 1); 1394 buf[sizeof(buf) - 1] = '\0'; 1395 if ((p = strrchr(buf, '/')) != NULL) { 1396 *p = '\0'; 1397 addrp = parse_ipmask(p + 1); 1398 } else { 1399 addrp = parse_ipmask(NULL); 1400 } 1401 memcpy(maskp, addrp, sizeof(*maskp)); 1402 1403 /* if a null mask is given, the name is ignored, like in "any/0" */ 1404 if (maskp->s_addr == 0U) 1405 strcpy(buf, "0.0.0.0"); 1406 1407 addrp = *addrpp = ipparse_hostnetwork(buf, naddrs); 1408 n = *naddrs; 1409 for (i = 0, j = 0; i < n; ++i) { 1410 addrp[j++].s_addr &= maskp->s_addr; 1411 for (k = 0; k < j - 1; ++k) 1412 if (addrp[k].s_addr == addrp[j-1].s_addr) { 1413 /* 1414 * Nuke the dup by copying an address from the 1415 * tail here, and check the current position 1416 * again (--j). 1417 */ 1418 memcpy(&addrp[--j], &addrp[--*naddrs], 1419 sizeof(struct in_addr)); 1420 break; 1421 } 1422 } 1423} 1424 1425const char *xtables_ip6addr_to_numeric(const struct in6_addr *addrp) 1426{ 1427 /* 0000:0000:0000:0000:0000:0000:000.000.000.000 1428 * 0000:0000:0000:0000:0000:0000:0000:0000 */ 1429 static char buf[50+1]; 1430 return inet_ntop(AF_INET6, addrp, buf, sizeof(buf)); 1431} 1432 1433static const char *ip6addr_to_host(const struct in6_addr *addr) 1434{ 1435 static char hostname[NI_MAXHOST]; 1436 struct sockaddr_in6 saddr; 1437 int err; 1438 1439 memset(&saddr, 0, sizeof(struct sockaddr_in6)); 1440 memcpy(&saddr.sin6_addr, addr, sizeof(*addr)); 1441 saddr.sin6_family = AF_INET6; 1442 1443 err = getnameinfo((const void *)&saddr, sizeof(struct sockaddr_in6), 1444 hostname, sizeof(hostname) - 1, NULL, 0, 0); 1445 if (err != 0) { 1446#ifdef DEBUG 1447 fprintf(stderr,"IP2Name: %s\n",gai_strerror(err)); 1448#endif 1449 return NULL; 1450 } 1451 1452#ifdef DEBUG 1453 fprintf (stderr, "\naddr2host: %s\n", hostname); 1454#endif 1455 return hostname; 1456} 1457 1458const char *xtables_ip6addr_to_anyname(const struct in6_addr *addr) 1459{ 1460 const char *name; 1461 1462 if ((name = ip6addr_to_host(addr)) != NULL) 1463 return name; 1464 1465 return xtables_ip6addr_to_numeric(addr); 1466} 1467 1468static int ip6addr_prefix_length(const struct in6_addr *k) 1469{ 1470 unsigned int bits = 0; 1471 uint32_t a, b, c, d; 1472 1473 a = ntohl(k->s6_addr32[0]); 1474 b = ntohl(k->s6_addr32[1]); 1475 c = ntohl(k->s6_addr32[2]); 1476 d = ntohl(k->s6_addr32[3]); 1477 while (a & 0x80000000U) { 1478 ++bits; 1479 a <<= 1; 1480 a |= (b >> 31) & 1; 1481 b <<= 1; 1482 b |= (c >> 31) & 1; 1483 c <<= 1; 1484 c |= (d >> 31) & 1; 1485 d <<= 1; 1486 } 1487 if (a != 0 || b != 0 || c != 0 || d != 0) 1488 return -1; 1489 return bits; 1490} 1491 1492const char *xtables_ip6mask_to_numeric(const struct in6_addr *addrp) 1493{ 1494 static char buf[50+2]; 1495 int l = ip6addr_prefix_length(addrp); 1496 1497 if (l == -1) { 1498 strcpy(buf, "/"); 1499 strcat(buf, xtables_ip6addr_to_numeric(addrp)); 1500 return buf; 1501 } 1502 sprintf(buf, "/%d", l); 1503 return buf; 1504} 1505 1506struct in6_addr *xtables_numeric_to_ip6addr(const char *num) 1507{ 1508 static struct in6_addr ap; 1509 int err; 1510 1511 if ((err = inet_pton(AF_INET6, num, &ap)) == 1) 1512 return ≈ 1513#ifdef DEBUG 1514 fprintf(stderr, "\nnumeric2addr: %d\n", err); 1515#endif 1516 return NULL; 1517} 1518 1519static struct in6_addr * 1520host_to_ip6addr(const char *name, unsigned int *naddr) 1521{ 1522 struct in6_addr *addr; 1523 struct addrinfo hints; 1524 struct addrinfo *res, *p; 1525 int err; 1526 unsigned int i; 1527 1528 memset(&hints, 0, sizeof(hints)); 1529 hints.ai_flags = AI_CANONNAME; 1530 hints.ai_family = AF_INET6; 1531 hints.ai_socktype = SOCK_RAW; 1532 1533 *naddr = 0; 1534 if ((err = getaddrinfo(name, NULL, &hints, &res)) != 0) { 1535#ifdef DEBUG 1536 fprintf(stderr,"Name2IP: %s\n",gai_strerror(err)); 1537#endif 1538 return NULL; 1539 } else { 1540 /* Find length of address chain */ 1541 for (p = res; p != NULL; p = p->ai_next) 1542 ++*naddr; 1543#ifdef DEBUG 1544 fprintf(stderr, "resolved: len=%d %s ", res->ai_addrlen, 1545 xtables_ip6addr_to_numeric(&((struct sockaddr_in6 *)res->ai_addr)->sin6_addr)); 1546#endif 1547 /* Copy each element of the address chain */ 1548 addr = xtables_calloc(*naddr, sizeof(struct in6_addr)); 1549 for (i = 0, p = res; p != NULL; p = p->ai_next) 1550 memcpy(&addr[i++], 1551 &((const struct sockaddr_in6 *)p->ai_addr)->sin6_addr, 1552 sizeof(struct in6_addr)); 1553 freeaddrinfo(res); 1554 return addr; 1555 } 1556 1557 return NULL; 1558} 1559 1560static struct in6_addr *network_to_ip6addr(const char *name) 1561{ 1562 /* abort();*/ 1563 /* TODO: not implemented yet, but the exception breaks the 1564 * name resolvation */ 1565 return NULL; 1566} 1567 1568static struct in6_addr * 1569ip6parse_hostnetwork(const char *name, unsigned int *naddrs) 1570{ 1571 struct in6_addr *addrp, *addrptmp; 1572 1573 if ((addrptmp = xtables_numeric_to_ip6addr(name)) != NULL || 1574 (addrptmp = network_to_ip6addr(name)) != NULL) { 1575 addrp = xtables_malloc(sizeof(struct in6_addr)); 1576 memcpy(addrp, addrptmp, sizeof(*addrp)); 1577 *naddrs = 1; 1578 return addrp; 1579 } 1580 if ((addrp = host_to_ip6addr(name, naddrs)) != NULL) 1581 return addrp; 1582 1583 xt_params->exit_err(PARAMETER_PROBLEM, "host/network `%s' not found", name); 1584} 1585 1586static struct in6_addr *parse_ip6mask(char *mask) 1587{ 1588 static struct in6_addr maskaddr; 1589 struct in6_addr *addrp; 1590 unsigned int bits; 1591 1592 if (mask == NULL) { 1593 /* no mask at all defaults to 128 bits */ 1594 memset(&maskaddr, 0xff, sizeof maskaddr); 1595 return &maskaddr; 1596 } 1597 if ((addrp = xtables_numeric_to_ip6addr(mask)) != NULL) 1598 return addrp; 1599 if (!xtables_strtoui(mask, NULL, &bits, 0, 128)) 1600 xt_params->exit_err(PARAMETER_PROBLEM, 1601 "invalid mask `%s' specified", mask); 1602 if (bits != 0) { 1603 char *p = (void *)&maskaddr; 1604 memset(p, 0xff, bits / 8); 1605 memset(p + (bits / 8) + 1, 0, (128 - bits) / 8); 1606 p[bits/8] = 0xff << (8 - (bits & 7)); 1607 return &maskaddr; 1608 } 1609 1610 memset(&maskaddr, 0, sizeof(maskaddr)); 1611 return &maskaddr; 1612} 1613 1614void 1615xtables_ip6parse_multiple(const char *name, struct in6_addr **addrpp, 1616 struct in6_addr **maskpp, unsigned int *naddrs) 1617{ 1618 static const struct in6_addr zero_addr; 1619 struct in6_addr *addrp; 1620 char buf[256], *p, *next; 1621 unsigned int len, i, j, n, count = 1; 1622 const char *loop = name; 1623 1624 while ((loop = strchr(loop, ',')) != NULL) { 1625 ++count; 1626 ++loop; /* skip ',' */ 1627 } 1628 1629 *addrpp = xtables_malloc(sizeof(struct in6_addr) * count); 1630 *maskpp = xtables_malloc(sizeof(struct in6_addr) * count); 1631 1632 loop = name; 1633 1634 for (i = 0; i < count /*NB: count can grow*/; ++i) { 1635 while (isspace(*loop)) 1636 ++loop; 1637 next = strchr(loop, ','); 1638 if (next != NULL) 1639 len = next - loop; 1640 else 1641 len = strlen(loop); 1642 if (len > sizeof(buf) - 1) 1643 xt_params->exit_err(PARAMETER_PROBLEM, 1644 "Hostname too long"); 1645 1646 strncpy(buf, loop, len); 1647 buf[len] = '\0'; 1648 if ((p = strrchr(buf, '/')) != NULL) { 1649 *p = '\0'; 1650 addrp = parse_ip6mask(p + 1); 1651 } else { 1652 addrp = parse_ip6mask(NULL); 1653 } 1654 memcpy(*maskpp + i, addrp, sizeof(*addrp)); 1655 1656 /* if a null mask is given, the name is ignored, like in "any/0" */ 1657 if (memcmp(*maskpp + i, &zero_addr, sizeof(zero_addr)) == 0) 1658 strcpy(buf, "::"); 1659 1660 addrp = ip6parse_hostnetwork(buf, &n); 1661 if (n > 1) { 1662 count += n - 1; 1663 *addrpp = xtables_realloc(*addrpp, 1664 sizeof(struct in6_addr) * count); 1665 *maskpp = xtables_realloc(*maskpp, 1666 sizeof(struct in6_addr) * count); 1667 for (j = 0; j < n; ++j) 1668 /* for each new addr */ 1669 memcpy(*addrpp + i + j, addrp + j, 1670 sizeof(*addrp)); 1671 for (j = 1; j < n; ++j) 1672 /* for each new mask */ 1673 memcpy(*maskpp + i + j, *maskpp + i, 1674 sizeof(*addrp)); 1675 i += n - 1; 1676 } else { 1677 memcpy(*addrpp + i, addrp, sizeof(*addrp)); 1678 } 1679 /* free what ip6parse_hostnetwork had allocated: */ 1680 free(addrp); 1681 if (next == NULL) 1682 break; 1683 loop = next + 1; 1684 } 1685 *naddrs = count; 1686 for (i = 0; i < count; ++i) 1687 for (j = 0; j < 4; ++j) 1688 (*addrpp+i)->s6_addr32[j] &= (*maskpp+i)->s6_addr32[j]; 1689} 1690 1691void xtables_ip6parse_any(const char *name, struct in6_addr **addrpp, 1692 struct in6_addr *maskp, unsigned int *naddrs) 1693{ 1694 static const struct in6_addr zero_addr; 1695 struct in6_addr *addrp; 1696 unsigned int i, j, k, n; 1697 char buf[256], *p; 1698 1699 strncpy(buf, name, sizeof(buf) - 1); 1700 buf[sizeof(buf)-1] = '\0'; 1701 if ((p = strrchr(buf, '/')) != NULL) { 1702 *p = '\0'; 1703 addrp = parse_ip6mask(p + 1); 1704 } else { 1705 addrp = parse_ip6mask(NULL); 1706 } 1707 memcpy(maskp, addrp, sizeof(*maskp)); 1708 1709 /* if a null mask is given, the name is ignored, like in "any/0" */ 1710 if (memcmp(maskp, &zero_addr, sizeof(zero_addr)) == 0) 1711 strcpy(buf, "::"); 1712 1713 addrp = *addrpp = ip6parse_hostnetwork(buf, naddrs); 1714 n = *naddrs; 1715 for (i = 0, j = 0; i < n; ++i) { 1716 for (k = 0; k < 4; ++k) 1717 addrp[j].s6_addr32[k] &= maskp->s6_addr32[k]; 1718 ++j; 1719 for (k = 0; k < j - 1; ++k) 1720 if (IN6_ARE_ADDR_EQUAL(&addrp[k], &addrp[j - 1])) { 1721 /* 1722 * Nuke the dup by copying an address from the 1723 * tail here, and check the current position 1724 * again (--j). 1725 */ 1726 memcpy(&addrp[--j], &addrp[--*naddrs], 1727 sizeof(struct in_addr)); 1728 break; 1729 } 1730 } 1731} 1732 1733void xtables_save_string(const char *value) 1734{ 1735 static const char no_quote_chars[] = "_-0123456789" 1736 "abcdefghijklmnopqrstuvwxyz" 1737 "ABCDEFGHIJKLMNOPQRSTUVWXYZ"; 1738 static const char escape_chars[] = "\"\\'"; 1739 size_t length; 1740 const char *p; 1741 1742 length = strspn(value, no_quote_chars); 1743 if (length > 0 && value[length] == 0) { 1744 /* no quoting required */ 1745 putchar(' '); 1746 fputs(value, stdout); 1747 } else { 1748 /* there is at least one dangerous character in the 1749 value, which we have to quote. Write double quotes 1750 around the value and escape special characters with 1751 a backslash */ 1752 printf(" \""); 1753 1754 for (p = strpbrk(value, escape_chars); p != NULL; 1755 p = strpbrk(value, escape_chars)) { 1756 if (p > value) 1757 fwrite(value, 1, p - value, stdout); 1758 putchar('\\'); 1759 putchar(*p); 1760 value = p + 1; 1761 } 1762 1763 /* print the rest and finish the double quoted 1764 string */ 1765 fputs(value, stdout); 1766 putchar('\"'); 1767 } 1768} 1769 1770const struct xtables_pprot xtables_chain_protos[] = { 1771 {"tcp", IPPROTO_TCP}, 1772 {"sctp", IPPROTO_SCTP}, 1773 {"udp", IPPROTO_UDP}, 1774 {"udplite", IPPROTO_UDPLITE}, 1775 {"icmp", IPPROTO_ICMP}, 1776 {"icmpv6", IPPROTO_ICMPV6}, 1777 {"ipv6-icmp", IPPROTO_ICMPV6}, 1778 {"esp", IPPROTO_ESP}, 1779 {"ah", IPPROTO_AH}, 1780 {"ipv6-mh", IPPROTO_MH}, 1781 {"mh", IPPROTO_MH}, 1782 {"all", 0}, 1783 {NULL}, 1784}; 1785 1786uint16_t 1787xtables_parse_protocol(const char *s) 1788{ 1789 const struct protoent *pent; 1790 unsigned int proto, i; 1791 1792 if (xtables_strtoui(s, NULL, &proto, 0, UINT8_MAX)) 1793 return proto; 1794 1795 /* first deal with the special case of 'all' to prevent 1796 * people from being able to redefine 'all' in nsswitch 1797 * and/or provoke expensive [not working] ldap/nis/... 1798 * lookups */ 1799 if (strcmp(s, "all") == 0) 1800 return 0; 1801 1802 pent = getprotobyname(s); 1803 if (pent != NULL) 1804 return pent->p_proto; 1805 1806 for (i = 0; i < ARRAY_SIZE(xtables_chain_protos); ++i) { 1807 if (xtables_chain_protos[i].name == NULL) 1808 continue; 1809 if (strcmp(s, xtables_chain_protos[i].name) == 0) 1810 return xtables_chain_protos[i].num; 1811 } 1812 xt_params->exit_err(PARAMETER_PROBLEM, 1813 "unknown protocol \"%s\" specified", s); 1814 return -1; 1815} 1816 1817int kernel_version; 1818 1819void get_kernel_version(void) 1820{ 1821 static struct utsname uts; 1822 int x = 0, y = 0, z = 0; 1823 1824 if (uname(&uts) == -1) { 1825 fprintf(stderr, "Unable to retrieve kernel version.\n"); 1826 xtables_free_opts(1); 1827 exit(1); 1828 } 1829 1830 sscanf(uts.release, "%d.%d.%d", &x, &y, &z); 1831 kernel_version = LINUX_VERSION(x, y, z); 1832} 1833