xtoptions.c revision fa9b759bacc0ad6a093892ef508811e7feb981b0
1/* 2 * Argument parser 3 * Copyright © Jan Engelhardt, 2011 4 * 5 * This program is free software; you can redistribute it and/or 6 * modify it under the terms of the GNU General Public License as 7 * published by the Free Software Foundation; either version 2 of 8 * the License, or (at your option) any later version. 9 */ 10#include <ctype.h> 11#include <errno.h> 12#include <getopt.h> 13#include <limits.h> 14#include <netdb.h> 15#include <stdbool.h> 16#include <stdint.h> 17#include <stdio.h> 18#include <stdlib.h> 19#include <string.h> 20#include <syslog.h> 21#include <arpa/inet.h> 22#include <netinet/ip.h> 23#include "xtables.h" 24#include "xshared.h" 25#ifndef IPTOS_NORMALSVC 26# define IPTOS_NORMALSVC 0 27#endif 28 29#define XTOPT_MKPTR(cb) \ 30 ((void *)((char *)(cb)->data + (cb)->entry->ptroff)) 31 32/** 33 * Simple key-value pairs for syslog levels 34 */ 35struct syslog_level { 36 char name[8]; 37 uint8_t level; 38}; 39 40struct tos_value_mask { 41 uint8_t value, mask; 42}; 43 44/** 45 * Creates getopt options from the x6-style option map, and assigns each a 46 * getopt id. 47 */ 48struct option * 49xtables_options_xfrm(struct option *orig_opts, struct option *oldopts, 50 const struct xt_option_entry *entry, unsigned int *offset) 51{ 52 unsigned int num_orig, num_old = 0, num_new, i; 53 struct option *merge, *mp; 54 55 if (entry == NULL) 56 return oldopts; 57 for (num_orig = 0; orig_opts[num_orig].name != NULL; ++num_orig) 58 ; 59 if (oldopts != NULL) 60 for (num_old = 0; oldopts[num_old].name != NULL; ++num_old) 61 ; 62 for (num_new = 0; entry[num_new].name != NULL; ++num_new) 63 ; 64 65 /* 66 * Since @oldopts also has @orig_opts already (and does so at the 67 * start), skip these entries. 68 */ 69 oldopts += num_orig; 70 num_old -= num_orig; 71 72 merge = malloc(sizeof(*mp) * (num_orig + num_old + num_new + 1)); 73 if (merge == NULL) 74 return NULL; 75 76 /* Let the base options -[ADI...] have precedence over everything */ 77 memcpy(merge, orig_opts, sizeof(*mp) * num_orig); 78 mp = merge + num_orig; 79 80 /* Second, the new options */ 81 xt_params->option_offset += XT_OPTION_OFFSET_SCALE; 82 *offset = xt_params->option_offset; 83 84 for (i = 0; i < num_new; ++i, ++mp, ++entry) { 85 mp->name = entry->name; 86 mp->has_arg = entry->type != XTTYPE_NONE; 87 mp->flag = NULL; 88 mp->val = entry->id + *offset; 89 } 90 91 /* Third, the old options */ 92 memcpy(mp, oldopts, sizeof(*mp) * num_old); 93 mp += num_old; 94 xtables_free_opts(0); 95 96 /* Clear trailing entry */ 97 memset(mp, 0, sizeof(*mp)); 98 return merge; 99} 100 101/** 102 * Require a simple integer. 103 */ 104static void xtopt_parse_int(struct xt_option_call *cb) 105{ 106 const struct xt_option_entry *entry = cb->entry; 107 unsigned long long lmin = 0, lmax = UINT32_MAX; 108 unsigned int value; 109 110 if (entry->type == XTTYPE_UINT8) 111 lmax = UINT8_MAX; 112 else if (entry->type == XTTYPE_UINT16) 113 lmax = UINT16_MAX; 114 else if (entry->type == XTTYPE_UINT64) 115 lmax = UINT64_MAX; 116 if (cb->entry->min != 0) 117 lmin = cb->entry->min; 118 if (cb->entry->max != 0) 119 lmax = cb->entry->max; 120 121 if (!xtables_strtoui(cb->arg, NULL, &value, lmin, lmax)) 122 xt_params->exit_err(PARAMETER_PROBLEM, 123 "%s: bad value for option \"--%s\", " 124 "or out of range (%llu-%llu).\n", 125 cb->ext_name, entry->name, lmin, lmax); 126 127 if (entry->type == XTTYPE_UINT8) { 128 cb->val.u8 = value; 129 if (entry->flags & XTOPT_PUT) 130 *(uint8_t *)XTOPT_MKPTR(cb) = cb->val.u8; 131 } else if (entry->type == XTTYPE_UINT16) { 132 cb->val.u16 = value; 133 if (entry->flags & XTOPT_PUT) 134 *(uint16_t *)XTOPT_MKPTR(cb) = cb->val.u16; 135 } else if (entry->type == XTTYPE_UINT32) { 136 cb->val.u32 = value; 137 if (entry->flags & XTOPT_PUT) 138 *(uint32_t *)XTOPT_MKPTR(cb) = cb->val.u32; 139 } else if (entry->type == XTTYPE_UINT64) { 140 cb->val.u64 = value; 141 if (entry->flags & XTOPT_PUT) 142 *(uint64_t *)XTOPT_MKPTR(cb) = cb->val.u64; 143 } 144} 145 146/** 147 * Require a simple floating point number. 148 */ 149static void xtopt_parse_float(struct xt_option_call *cb) 150{ 151 const struct xt_option_entry *entry = cb->entry; 152 double value; 153 char *end; 154 155 value = strtod(cb->arg, &end); 156 if (end == cb->arg || *end != '\0' || 157 (entry->min != entry->max && 158 (value < entry->min || value > entry->max))) 159 xt_params->exit_err(PARAMETER_PROBLEM, 160 "%s: bad value for option \"--%s\", " 161 "or out of range (%u-%u).\n", 162 cb->ext_name, entry->name, entry->min, entry->max); 163 164 cb->val.dbl = value; 165 if (entry->flags & XTOPT_PUT) 166 *(double *)XTOPT_MKPTR(cb) = cb->val.dbl; 167} 168 169/** 170 * Multiple integer parse routine. 171 * 172 * This function is capable of parsing any number of fields. Only the first 173 * two values from the string will be put into @cb however (and as such, 174 * @cb->val.uXX_range is just that large) to cater for the few extensions that 175 * do not have a range[2] field, but {min, max}, and which cannot use 176 * XTOPT_POINTER. 177 */ 178static void xtopt_parse_mint(struct xt_option_call *cb) 179{ 180 const struct xt_option_entry *entry = cb->entry; 181 const char *arg = cb->arg; 182 size_t esize = sizeof(uint32_t); 183 char *put = XTOPT_MKPTR(cb); 184 unsigned int maxiter, value; 185 char *end = ""; 186 char sep = ':'; 187 188 if (entry->type == XTTYPE_UINT8RC) 189 esize = sizeof(uint8_t); 190 else if (entry->type == XTTYPE_UINT16RC) 191 esize = sizeof(uint16_t); 192 else if (entry->type == XTTYPE_UINT64RC) 193 esize = sizeof(uint64_t); 194 maxiter = entry->size / esize; 195 if (maxiter == 0) 196 maxiter = 2; /* ARRAY_SIZE(cb->val.uXX_range) */ 197 if (entry->size % esize != 0) 198 xt_params->exit_err(OTHER_PROBLEM, "%s: memory block does " 199 "not have proper size\n", __func__); 200 201 cb->nvals = 0; 202 for (arg = cb->arg; ; arg = end + 1) { 203 if (cb->nvals == maxiter) 204 xt_params->exit_err(PARAMETER_PROBLEM, "%s: Too many " 205 "components for option \"--%s\" (max: %u)\n", 206 cb->ext_name, entry->name, maxiter); 207 if (!xtables_strtoui(arg, &end, &value, 0, UINT32_MAX)) 208 xt_params->exit_err(PARAMETER_PROBLEM, 209 "%s: bad value for option \"--%s\", " 210 "or out of range (0-%u).\n", 211 cb->ext_name, entry->name, UINT32_MAX); 212 if (*end != '\0' && *end != sep) 213 xt_params->exit_err(PARAMETER_PROBLEM, 214 "%s: Argument to \"--%s\" has unexpected " 215 "characters.\n", cb->ext_name, entry->name); 216 if (cb->nvals < ARRAY_SIZE(cb->val.u32_range)) { 217 if (entry->type == XTTYPE_UINT8RC) 218 cb->val.u8_range[cb->nvals] = value; 219 else if (entry->type == XTTYPE_UINT16RC) 220 cb->val.u16_range[cb->nvals] = value; 221 else if (entry->type == XTTYPE_UINT32RC) 222 cb->val.u32_range[cb->nvals] = value; 223 else if (entry->type == XTTYPE_UINT64RC) 224 cb->val.u64_range[cb->nvals] = value; 225 } 226 ++cb->nvals; 227 if (entry->flags & XTOPT_PUT) { 228 if (entry->type == XTTYPE_UINT8RC) 229 *(uint8_t *)put = value; 230 else if (entry->type == XTTYPE_UINT16RC) 231 *(uint16_t *)put = value; 232 else if (entry->type == XTTYPE_UINT32RC) 233 *(uint32_t *)put = value; 234 else if (entry->type == XTTYPE_UINT64RC) 235 *(uint64_t *)put = value; 236 put += esize; 237 } 238 if (*end == '\0') 239 break; 240 } 241} 242 243static void xtopt_parse_string(struct xt_option_call *cb) 244{ 245 const struct xt_option_entry *entry = cb->entry; 246 size_t z = strlen(cb->arg); 247 char *p; 248 249 if (entry->min != 0 && z < entry->min) 250 xt_params->exit_err(PARAMETER_PROBLEM, 251 "Argument must have a minimum length of " 252 "%u characters\n", entry->min); 253 if (entry->max != 0 && z > entry->max) 254 xt_params->exit_err(PARAMETER_PROBLEM, 255 "Argument must have a maximum length of " 256 "%u characters\n", entry->max); 257 if (!(entry->flags & XTOPT_PUT)) 258 return; 259 if (z >= entry->size) 260 z = entry->size - 1; 261 p = XTOPT_MKPTR(cb); 262 strncpy(p, cb->arg, z); 263 p[z] = '\0'; 264} 265 266static const struct tos_symbol_info { 267 unsigned char value; 268 const char *name; 269} tos_symbol_names[] = { 270 {IPTOS_LOWDELAY, "Minimize-Delay"}, 271 {IPTOS_THROUGHPUT, "Maximize-Throughput"}, 272 {IPTOS_RELIABILITY, "Maximize-Reliability"}, 273 {IPTOS_MINCOST, "Minimize-Cost"}, 274 {IPTOS_NORMALSVC, "Normal-Service"}, 275 {}, 276}; 277 278/* 279 * tos_parse_numeric - parse a string like "15/255" 280 * 281 * @str: input string 282 * @tvm: (value/mask) tuple 283 * @max: maximum allowed value (must be pow(2,some_int)-1) 284 */ 285static bool tos_parse_numeric(const char *str, struct xt_option_call *cb, 286 unsigned int max) 287{ 288 unsigned int value; 289 char *end; 290 291 xtables_strtoui(str, &end, &value, 0, max); 292 cb->val.tos_value = value; 293 cb->val.tos_mask = max; 294 295 if (*end == '/') { 296 const char *p = end + 1; 297 298 if (!xtables_strtoui(p, &end, &value, 0, max)) 299 xtables_error(PARAMETER_PROBLEM, "Illegal value: \"%s\"", 300 str); 301 cb->val.tos_mask = value; 302 } 303 304 if (*end != '\0') 305 xtables_error(PARAMETER_PROBLEM, "Illegal value: \"%s\"", str); 306 return true; 307} 308 309/** 310 * @str: input string 311 * @tvm: (value/mask) tuple 312 * @def_mask: mask to force when a symbolic name is used 313 */ 314static void xtopt_parse_tosmask(struct xt_option_call *cb) 315{ 316 const struct tos_symbol_info *symbol; 317 char *tmp; 318 319 if (xtables_strtoui(cb->arg, &tmp, NULL, 0, UINT8_MAX)) { 320 tos_parse_numeric(cb->arg, cb, UINT8_MAX); 321 return; 322 } 323 /* 324 * This is our way we deal with different defaults 325 * for different revisions. 326 */ 327 cb->val.tos_mask = cb->entry->max; 328 for (symbol = tos_symbol_names; symbol->name != NULL; ++symbol) 329 if (strcasecmp(cb->arg, symbol->name) == 0) { 330 cb->val.tos_value = symbol->value; 331 return; 332 } 333 334 xtables_error(PARAMETER_PROBLEM, "Symbolic name \"%s\" is unknown", 335 cb->arg); 336} 337 338/** 339 * Validate the input for being conformant to "mark[/mask]". 340 */ 341static void xtopt_parse_markmask(struct xt_option_call *cb) 342{ 343 unsigned int mark = 0, mask = ~0U; 344 char *end; 345 346 if (!xtables_strtoui(cb->arg, &end, &mark, 0, UINT32_MAX)) 347 xt_params->exit_err(PARAMETER_PROBLEM, 348 "%s: bad mark value for option \"--%s\", " 349 "or out of range.\n", 350 cb->ext_name, cb->entry->name); 351 if (*end == '/' && 352 !xtables_strtoui(end + 1, &end, &mask, 0, UINT32_MAX)) 353 xt_params->exit_err(PARAMETER_PROBLEM, 354 "%s: bad mask value for option \"--%s\", " 355 "or out of range.\n", 356 cb->ext_name, cb->entry->name); 357 if (*end != '\0') 358 xt_params->exit_err(PARAMETER_PROBLEM, 359 "%s: trailing garbage after value " 360 "for option \"--%s\".\n", 361 cb->ext_name, cb->entry->name); 362 cb->val.mark = mark; 363 cb->val.mask = mask; 364} 365 366static int xtopt_sysloglvl_compare(const void *a, const void *b) 367{ 368 const char *name = a; 369 const struct syslog_level *entry = b; 370 371 return strcmp(name, entry->name); 372} 373 374static void xtopt_parse_sysloglevel(struct xt_option_call *cb) 375{ 376 static const struct syslog_level log_names[] = { /* must be sorted */ 377 {"alert", LOG_ALERT}, 378 {"crit", LOG_CRIT}, 379 {"debug", LOG_DEBUG}, 380 {"emerg", LOG_EMERG}, 381 {"error", LOG_ERR}, /* deprecated */ 382 {"info", LOG_INFO}, 383 {"notice", LOG_NOTICE}, 384 {"panic", LOG_EMERG}, /* deprecated */ 385 {"warning", LOG_WARNING}, 386 }; 387 const struct syslog_level *e; 388 unsigned int num = 0; 389 390 if (!xtables_strtoui(cb->arg, NULL, &num, 0, 7)) { 391 e = bsearch(cb->arg, log_names, ARRAY_SIZE(log_names), 392 sizeof(*log_names), xtopt_sysloglvl_compare); 393 if (e == NULL) 394 xt_params->exit_err(PARAMETER_PROBLEM, 395 "log level \"%s\" unknown\n", cb->arg); 396 num = e->level; 397 } 398 cb->val.syslog_level = num; 399 if (cb->entry->flags & XTOPT_PUT) 400 *(uint8_t *)XTOPT_MKPTR(cb) = num; 401} 402 403static void *xtables_sa_host(const void *sa, unsigned int afproto) 404{ 405 if (afproto == AF_INET6) 406 return &((struct sockaddr_in6 *)sa)->sin6_addr; 407 else if (afproto == AF_INET) 408 return &((struct sockaddr_in *)sa)->sin_addr; 409 return (void *)sa; 410} 411 412static socklen_t xtables_sa_hostlen(unsigned int afproto) 413{ 414 if (afproto == AF_INET6) 415 return sizeof(struct in6_addr); 416 else if (afproto == AF_INET) 417 return sizeof(struct in_addr); 418 return 0; 419} 420 421/** 422 * Accepts: a hostname (DNS), or a single inetaddr - without any mask. The 423 * result is stored in @cb->val.haddr. Additionally, @cb->val.hmask and 424 * @cb->val.hlen are set for completeness to the appropriate values. 425 */ 426static void xtopt_parse_host(struct xt_option_call *cb) 427{ 428 struct addrinfo hints = {.ai_family = afinfo->family}; 429 unsigned int adcount = 0; 430 struct addrinfo *res, *p; 431 int ret; 432 433 ret = getaddrinfo(cb->arg, NULL, &hints, &res); 434 if (ret < 0) 435 xt_params->exit_err(PARAMETER_PROBLEM, 436 "getaddrinfo: %s\n", gai_strerror(ret)); 437 438 memset(&cb->val.hmask, 0xFF, sizeof(cb->val.hmask)); 439 cb->val.hlen = (afinfo->family == NFPROTO_IPV4) ? 32 : 128; 440 441 for (p = res; p != NULL; p = p->ai_next) { 442 if (adcount == 0) { 443 memset(&cb->val.haddr, 0, sizeof(cb->val.haddr)); 444 memcpy(&cb->val.haddr, 445 xtables_sa_host(p->ai_addr, p->ai_family), 446 xtables_sa_hostlen(p->ai_family)); 447 ++adcount; 448 continue; 449 } 450 if (memcmp(&cb->val.haddr, 451 xtables_sa_host(p->ai_addr, p->ai_family), 452 xtables_sa_hostlen(p->ai_family)) != 0) 453 xt_params->exit_err(PARAMETER_PROBLEM, 454 "%s resolves to more than one address\n", 455 cb->arg); 456 } 457 458 freeaddrinfo(res); 459 if (cb->entry->flags & XTOPT_PUT) 460 /* Validation in xtables_option_metavalidate */ 461 memcpy(XTOPT_MKPTR(cb), &cb->val.haddr, 462 sizeof(cb->val.haddr)); 463} 464 465/** 466 * @name: port name, or number as a string (e.g. "http" or "80") 467 * 468 * Resolve a port name to a number. Returns the port number in integral 469 * form on success, or <0 on error. (errno will not be set.) 470 */ 471static int xtables_getportbyname(const char *name) 472{ 473 struct addrinfo *res = NULL, *p; 474 int ret; 475 476 ret = getaddrinfo(NULL, name, NULL, &res); 477 if (ret < 0) 478 return -1; 479 ret = -1; 480 for (p = res; p != NULL; p = p->ai_next) { 481 if (p->ai_family == AF_INET6) { 482 ret = ((struct sockaddr_in6 *)p->ai_addr)->sin6_port; 483 break; 484 } else if (p->ai_family == AF_INET) { 485 ret = ((struct sockaddr_in *)p->ai_addr)->sin_port; 486 break; 487 } 488 } 489 freeaddrinfo(res); 490 if (ret < 0) 491 return ret; 492 return ntohs(ret); 493} 494 495/** 496 * Validate and parse a port specification and put the result into 497 * @cb->val.port. 498 */ 499static void xtopt_parse_port(struct xt_option_call *cb) 500{ 501 int ret; 502 503 ret = xtables_getportbyname(cb->arg); 504 if (ret < 0) 505 xt_params->exit_err(PARAMETER_PROBLEM, 506 "Port \"%s\" does not resolve to anything.\n", 507 cb->arg); 508 cb->val.port = ret; 509 if (cb->entry->type == XTTYPE_PORT_NE) 510 cb->val.port = htons(cb->val.port); 511 if (cb->entry->flags & XTOPT_PUT) 512 *(uint16_t *)XTOPT_MKPTR(cb) = cb->val.port; 513} 514 515static void xtopt_parse_mport(struct xt_option_call *cb) 516{ 517 static const size_t esize = sizeof(uint16_t); 518 const struct xt_option_entry *entry = cb->entry; 519 char *lo_arg, *wp_arg, *arg; 520 unsigned int maxiter; 521 int value; 522 523 wp_arg = lo_arg = strdup(cb->arg); 524 if (lo_arg == NULL) 525 xt_params->exit_err(RESOURCE_PROBLEM, "strdup"); 526 527 maxiter = entry->size / esize; 528 if (maxiter == 0) 529 maxiter = 2; /* ARRAY_SIZE(cb->val.port_range) */ 530 if (entry->size % esize != 0) 531 xt_params->exit_err(OTHER_PROBLEM, "%s: memory block does " 532 "not have proper size\n", __func__); 533 534 cb->val.port_range[0] = 0; 535 cb->val.port_range[1] = UINT16_MAX; 536 cb->nvals = 0; 537 538 while ((arg = strsep(&wp_arg, ":")) != NULL) { 539 if (cb->nvals == maxiter) 540 xt_params->exit_err(PARAMETER_PROBLEM, "%s: Too many " 541 "components for option \"--%s\" (max: %u)\n", 542 cb->ext_name, entry->name, maxiter); 543 if (*arg == '\0') { 544 ++cb->nvals; 545 continue; 546 } 547 548 value = xtables_getportbyname(arg); 549 if (value < 0) 550 xt_params->exit_err(PARAMETER_PROBLEM, 551 "Port \"%s\" does not resolve to " 552 "anything.\n", arg); 553 if (entry->type == XTTYPE_PORTRC_NE) 554 value = htons(value); 555 if (cb->nvals < ARRAY_SIZE(cb->val.port_range)) 556 cb->val.port_range[cb->nvals] = value; 557 ++cb->nvals; 558 } 559 560 if (cb->nvals == 1) { 561 cb->val.port_range[1] = cb->val.port_range[0]; 562 ++cb->nvals; 563 } 564 if (entry->flags & XTOPT_PUT) 565 memcpy(XTOPT_MKPTR(cb), cb->val.port_range, sizeof(uint16_t) * 566 (cb->nvals <= maxiter ? cb->nvals : maxiter)); 567 free(lo_arg); 568} 569 570/** 571 * Parse an integer and ensure it is within the address family's prefix length 572 * limits. The result is stored in @cb->val.hlen. 573 */ 574static void xtopt_parse_plen(struct xt_option_call *cb) 575{ 576 const struct xt_option_entry *entry = cb->entry; 577 unsigned int prefix_len = 128; /* happiness is a warm gcc */ 578 579 cb->val.hlen = (afinfo->family == NFPROTO_IPV4) ? 32 : 128; 580 if (!xtables_strtoui(cb->arg, NULL, &prefix_len, 0, cb->val.hlen)) 581 xt_params->exit_err(PARAMETER_PROBLEM, 582 "%s: bad value for option \"--%s\", " 583 "or out of range (%u-%u).\n", 584 cb->ext_name, entry->name, 0, cb->val.hlen); 585 586 cb->val.hlen = prefix_len; 587} 588 589/** 590 * Reuse xtopt_parse_plen for testing the integer. Afterwards convert this to 591 * a bitmask, and make it available through @cb->val.hmask (hlen remains 592 * valid). If %XTOPT_PUT is used, hmask will be copied to the target area. 593 */ 594static void xtopt_parse_plenmask(struct xt_option_call *cb) 595{ 596 const struct xt_option_entry *entry = cb->entry; 597 uint32_t *mask = cb->val.hmask.all; 598 599 xtopt_parse_plen(cb); 600 601 memset(mask, 0xFF, sizeof(union nf_inet_addr)); 602 /* This shifting is AF-independent. */ 603 if (cb->val.hlen == 0) { 604 mask[0] = mask[1] = mask[2] = mask[3] = 0; 605 } else if (cb->val.hlen <= 32) { 606 mask[0] <<= 32 - cb->val.hlen; 607 mask[1] = mask[2] = mask[3] = 0; 608 } else if (cb->val.hlen <= 64) { 609 mask[1] <<= 32 - (cb->val.hlen - 32); 610 mask[2] = mask[3] = 0; 611 } else if (cb->val.hlen <= 96) { 612 mask[2] <<= 32 - (cb->val.hlen - 64); 613 mask[3] = 0; 614 } else if (cb->val.hlen <= 128) { 615 mask[3] <<= 32 - (cb->val.hlen - 96); 616 } 617 mask[0] = htonl(mask[0]); 618 mask[1] = htonl(mask[1]); 619 mask[2] = htonl(mask[2]); 620 mask[3] = htonl(mask[3]); 621 if (entry->flags & XTOPT_PUT) 622 memcpy(XTOPT_MKPTR(cb), mask, sizeof(union nf_inet_addr)); 623} 624 625static void (*const xtopt_subparse[])(struct xt_option_call *) = { 626 [XTTYPE_UINT8] = xtopt_parse_int, 627 [XTTYPE_UINT16] = xtopt_parse_int, 628 [XTTYPE_UINT32] = xtopt_parse_int, 629 [XTTYPE_UINT64] = xtopt_parse_int, 630 [XTTYPE_UINT8RC] = xtopt_parse_mint, 631 [XTTYPE_UINT16RC] = xtopt_parse_mint, 632 [XTTYPE_UINT32RC] = xtopt_parse_mint, 633 [XTTYPE_UINT64RC] = xtopt_parse_mint, 634 [XTTYPE_DOUBLE] = xtopt_parse_float, 635 [XTTYPE_STRING] = xtopt_parse_string, 636 [XTTYPE_TOSMASK] = xtopt_parse_tosmask, 637 [XTTYPE_MARKMASK32] = xtopt_parse_markmask, 638 [XTTYPE_SYSLOGLEVEL] = xtopt_parse_sysloglevel, 639 [XTTYPE_HOST] = xtopt_parse_host, 640 [XTTYPE_PORT] = xtopt_parse_port, 641 [XTTYPE_PORT_NE] = xtopt_parse_port, 642 [XTTYPE_PORTRC] = xtopt_parse_mport, 643 [XTTYPE_PORTRC_NE] = xtopt_parse_mport, 644 [XTTYPE_PLEN] = xtopt_parse_plen, 645 [XTTYPE_PLENMASK] = xtopt_parse_plenmask, 646}; 647 648static const size_t xtopt_psize[] = { 649 /* 650 * All types not listed here, and thus essentially being initialized to 651 * zero have zero on purpose. 652 */ 653 [XTTYPE_UINT8] = sizeof(uint8_t), 654 [XTTYPE_UINT16] = sizeof(uint16_t), 655 [XTTYPE_UINT32] = sizeof(uint32_t), 656 [XTTYPE_UINT64] = sizeof(uint64_t), 657 [XTTYPE_UINT8RC] = sizeof(uint8_t[2]), 658 [XTTYPE_UINT16RC] = sizeof(uint16_t[2]), 659 [XTTYPE_UINT32RC] = sizeof(uint32_t[2]), 660 [XTTYPE_UINT64RC] = sizeof(uint64_t[2]), 661 [XTTYPE_DOUBLE] = sizeof(double), 662 [XTTYPE_STRING] = -1, 663 [XTTYPE_SYSLOGLEVEL] = sizeof(uint8_t), 664 [XTTYPE_HOST] = sizeof(union nf_inet_addr), 665 [XTTYPE_PORT] = sizeof(uint16_t), 666 [XTTYPE_PORT_NE] = sizeof(uint16_t), 667 [XTTYPE_PORTRC] = sizeof(uint16_t[2]), 668 [XTTYPE_PORTRC_NE] = sizeof(uint16_t[2]), 669 [XTTYPE_PLENMASK] = sizeof(union nf_inet_addr), 670}; 671 672/** 673 * The master option parsing routine. May be used for the ".x6_parse" 674 * function pointer in extensions if fully automatic parsing is desired. 675 * It may be also called manually from a custom x6_parse function. 676 */ 677void xtables_option_parse(struct xt_option_call *cb) 678{ 679 const struct xt_option_entry *entry = cb->entry; 680 unsigned int eflag = 1 << cb->entry->id; 681 682 /* 683 * With {.id = P_FOO, .excl = P_FOO} we can have simple double-use 684 * prevention. Though it turned out that this is too much typing (most 685 * of the options are one-time use only), so now we also have 686 * %XTOPT_MULTI. 687 */ 688 if ((!(entry->flags & XTOPT_MULTI) || (entry->excl & eflag)) && 689 cb->xflags & eflag) 690 xt_params->exit_err(PARAMETER_PROBLEM, 691 "%s: option \"--%s\" can only be used once.\n", 692 cb->ext_name, cb->entry->name); 693 if (cb->invert && !(entry->flags & XTOPT_INVERT)) 694 xt_params->exit_err(PARAMETER_PROBLEM, 695 "%s: option \"--%s\" cannot be inverted.\n", 696 cb->ext_name, entry->name); 697 if (entry->type != XTTYPE_NONE && optarg == NULL) 698 xt_params->exit_err(PARAMETER_PROBLEM, 699 "%s: option \"--%s\" requires an argument.\n", 700 cb->ext_name, entry->name); 701 if (entry->type <= ARRAY_SIZE(xtopt_subparse) && 702 xtopt_subparse[entry->type] != NULL) 703 xtopt_subparse[entry->type](cb); 704 /* Exclusion with other flags tested later in finalize. */ 705 cb->xflags |= 1 << entry->id; 706} 707 708/** 709 * Verifies that an extension's option map descriptor is valid, and ought to 710 * be called right after the extension has been loaded, and before option 711 * merging/xfrm. 712 */ 713void xtables_option_metavalidate(const char *name, 714 const struct xt_option_entry *entry) 715{ 716 for (; entry->name != NULL; ++entry) { 717 if (entry->id >= CHAR_BIT * sizeof(unsigned int) || 718 entry->id >= XT_OPTION_OFFSET_SCALE) 719 xt_params->exit_err(OTHER_PROBLEM, 720 "Extension %s uses invalid ID %u\n", 721 name, entry->id); 722 if (!(entry->flags & XTOPT_PUT)) 723 continue; 724 if (entry->type >= ARRAY_SIZE(xtopt_psize) || 725 xtopt_psize[entry->type] == 0) 726 xt_params->exit_err(OTHER_PROBLEM, 727 "%s: entry type of option \"--%s\" cannot be " 728 "combined with XTOPT_PUT\n", 729 name, entry->name); 730 if (xtopt_psize[entry->type] != -1 && 731 xtopt_psize[entry->type] != entry->size) 732 xt_params->exit_err(OTHER_PROBLEM, 733 "%s: option \"--%s\" points to a memory block " 734 "of wrong size (expected %zu, got %zu)\n", 735 name, entry->name, 736 xtopt_psize[entry->type], entry->size); 737 } 738} 739 740/** 741 * Find an option entry by its id. 742 */ 743static const struct xt_option_entry * 744xtables_option_lookup(const struct xt_option_entry *entry, unsigned int id) 745{ 746 for (; entry->name != NULL; ++entry) 747 if (entry->id == id) 748 return entry; 749 return NULL; 750} 751 752/** 753 * @c: getopt id (i.e. with offset) 754 * @fw: struct ipt_entry or ip6t_entry 755 * 756 * Dispatch arguments to the appropriate parse function, based upon the 757 * extension's choice of API. 758 */ 759void xtables_option_tpcall(unsigned int c, char **argv, bool invert, 760 struct xtables_target *t, void *fw) 761{ 762 struct xt_option_call cb; 763 764 if (t->x6_parse == NULL) { 765 if (t->parse != NULL) 766 t->parse(c - t->option_offset, argv, invert, 767 &t->tflags, fw, &t->t); 768 return; 769 } 770 771 c -= t->option_offset; 772 cb.entry = xtables_option_lookup(t->x6_options, c); 773 if (cb.entry == NULL) 774 xtables_error(OTHER_PROBLEM, 775 "Extension does not know id %u\n", c); 776 cb.arg = optarg; 777 cb.invert = invert; 778 cb.ext_name = t->name; 779 cb.data = t->t->data; 780 cb.xflags = t->tflags; 781 cb.target = &t->t; 782 t->x6_parse(&cb); 783 t->tflags = cb.xflags; 784} 785 786/** 787 * @c: getopt id (i.e. with offset) 788 * @fw: struct ipt_entry or ip6t_entry 789 * 790 * Dispatch arguments to the appropriate parse function, based upon the 791 * extension's choice of API. 792 */ 793void xtables_option_mpcall(unsigned int c, char **argv, bool invert, 794 struct xtables_match *m, void *fw) 795{ 796 struct xt_option_call cb; 797 798 if (m->x6_parse == NULL) { 799 if (m->parse != NULL) 800 m->parse(c - m->option_offset, argv, invert, 801 &m->mflags, fw, &m->m); 802 return; 803 } 804 805 c -= m->option_offset; 806 cb.entry = xtables_option_lookup(m->x6_options, c); 807 if (cb.entry == NULL) 808 xtables_error(OTHER_PROBLEM, 809 "Extension does not know id %u\n", c); 810 cb.arg = optarg; 811 cb.invert = invert; 812 cb.ext_name = m->name; 813 cb.data = m->m->data; 814 cb.xflags = m->mflags; 815 cb.match = &m->m; 816 m->x6_parse(&cb); 817 m->mflags = cb.xflags; 818} 819 820/** 821 * @name: name of extension 822 * @entry: current option (from all ext's entries) being validated 823 * @xflags: flags the extension has collected 824 * @i: conflicting option (id) to test for 825 */ 826static void 827xtables_option_fcheck2(const char *name, const struct xt_option_entry *entry, 828 const struct xt_option_entry *other, 829 unsigned int xflags) 830{ 831 unsigned int ef = 1 << entry->id, of = 1 << other->id; 832 833 if (entry->also & of && !(xflags & of)) 834 xt_params->exit_err(PARAMETER_PROBLEM, 835 "%s: option \"--%s\" also requires \"--%s\".\n", 836 name, entry->name, other->name); 837 838 if (!(entry->excl & of)) 839 /* Use of entry does not collide with other option, good. */ 840 return; 841 if ((xflags & (ef | of)) != (ef | of)) 842 /* Conflicting options were not used. */ 843 return; 844 845 xt_params->exit_err(PARAMETER_PROBLEM, 846 "%s: option \"--%s\" cannot be used together with \"--%s\".\n", 847 name, entry->name, other->name); 848} 849 850/** 851 * @name: name of extension 852 * @xflags: accumulated flags 853 * @entry: extension's option table 854 * 855 * Check that all option constraints have been met. This effectively replaces 856 * ->final_check of the older API. 857 */ 858void xtables_options_fcheck(const char *name, unsigned int xflags, 859 const struct xt_option_entry *table) 860{ 861 const struct xt_option_entry *entry, *other; 862 unsigned int i; 863 864 for (entry = table; entry->name != NULL; ++entry) { 865 if (entry->flags & XTOPT_MAND && 866 !(xflags & (1 << entry->id))) 867 xt_params->exit_err(PARAMETER_PROBLEM, 868 "%s: option \"--%s\" must be specified\n", 869 name, entry->name); 870 871 for (i = 0; i < CHAR_BIT * sizeof(entry->id); ++i) { 872 if (entry->id == i) 873 /* 874 * Avoid conflict with self. Multi-use check 875 * was done earlier in xtables_option_parse. 876 */ 877 continue; 878 other = xtables_option_lookup(table, i); 879 if (other == NULL) 880 continue; 881 xtables_option_fcheck2(name, entry, other, xflags); 882 } 883 } 884} 885 886/** 887 * Dispatch arguments to the appropriate final_check function, based upon the 888 * extension's choice of API. 889 */ 890void xtables_option_tfcall(struct xtables_target *t) 891{ 892 if (t->x6_fcheck != NULL) { 893 struct xt_fcheck_call cb; 894 895 cb.ext_name = t->name; 896 cb.data = t->t->data; 897 cb.xflags = t->tflags; 898 t->x6_fcheck(&cb); 899 } else if (t->final_check != NULL) { 900 t->final_check(t->tflags); 901 } 902 if (t->x6_options != NULL) 903 xtables_options_fcheck(t->name, t->tflags, t->x6_options); 904} 905 906/** 907 * Dispatch arguments to the appropriate final_check function, based upon the 908 * extension's choice of API. 909 */ 910void xtables_option_mfcall(struct xtables_match *m) 911{ 912 if (m->x6_fcheck != NULL) { 913 struct xt_fcheck_call cb; 914 915 cb.ext_name = m->name; 916 cb.data = m->m->data; 917 cb.xflags = m->mflags; 918 m->x6_fcheck(&cb); 919 } else if (m->final_check != NULL) { 920 m->final_check(m->mflags); 921 } 922 if (m->x6_options != NULL) 923 xtables_options_fcheck(m->name, m->mflags, m->x6_options); 924} 925 926struct xtables_lmap *xtables_lmap_init(const char *file) 927{ 928 struct xtables_lmap *lmap_head = NULL, *lmap_prev = NULL, *lmap_this; 929 char buf[512]; 930 FILE *fp; 931 char *cur, *nxt; 932 int id; 933 934 fp = fopen(file, "re"); 935 if (fp == NULL) 936 return NULL; 937 938 while (fgets(buf, sizeof(buf), fp) != NULL) { 939 cur = buf; 940 while (isspace(*cur)) 941 ++cur; 942 if (*cur == '#' || *cur == '\n' || *cur == '\0') 943 continue; 944 945 /* iproute2 allows hex and dec format */ 946 errno = 0; 947 id = strtoul(cur, &nxt, strncmp(cur, "0x", 2) == 0 ? 16 : 10); 948 if (nxt == cur || errno != 0) 949 continue; 950 951 /* same boundaries as in iproute2 */ 952 if (id < 0 || id > 255) 953 continue; 954 cur = nxt; 955 956 if (!isspace(*cur)) 957 continue; 958 while (isspace(*cur)) 959 ++cur; 960 if (*cur == '#' || *cur == '\n' || *cur == '\0') 961 continue; 962 nxt = cur; 963 while (*nxt != '\0' && !isspace(*nxt)) 964 ++nxt; 965 if (nxt == cur) 966 continue; 967 *nxt = '\0'; 968 969 /* found valid data */ 970 lmap_this = malloc(sizeof(*lmap_this)); 971 if (lmap_this == NULL) { 972 perror("malloc"); 973 goto out; 974 } 975 lmap_this->id = id; 976 lmap_this->name = strdup(cur); 977 if (lmap_this->name == NULL) { 978 free(lmap_this); 979 goto out; 980 } 981 lmap_this->next = NULL; 982 983 if (lmap_prev != NULL) 984 lmap_prev->next = lmap_this; 985 else 986 lmap_head = lmap_this; 987 lmap_prev = lmap_this; 988 } 989 990 fclose(fp); 991 return lmap_head; 992 out: 993 xtables_lmap_free(lmap_head); 994 return NULL; 995} 996 997void xtables_lmap_free(struct xtables_lmap *head) 998{ 999 struct xtables_lmap *next; 1000 1001 for (; head != NULL; head = next) { 1002 next = head->next; 1003 free(head->name); 1004 free(head); 1005 } 1006} 1007 1008int xtables_lmap_name2id(const struct xtables_lmap *head, const char *name) 1009{ 1010 for (; head != NULL; head = head->next) 1011 if (strcmp(head->name, name) == 0) 1012 return head->id; 1013 return -1; 1014} 1015 1016const char *xtables_lmap_id2name(const struct xtables_lmap *head, int id) 1017{ 1018 for (; head != NULL; head = head->next) 1019 if (head->id == id) 1020 return head->name; 1021 return NULL; 1022} 1023