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      1 /* Code to take an iptables-style command line and do it. */
      2 
      3 /*
      4  * Author: Paul.Russell (at) rustcorp.com.au and mneuling (at) radlogic.com.au
      5  *
      6  * (C) 2000-2002 by the netfilter coreteam <coreteam (at) netfilter.org>:
      7  * 		    Paul 'Rusty' Russell <rusty (at) rustcorp.com.au>
      8  * 		    Marc Boucher <marc+nf (at) mbsi.ca>
      9  * 		    James Morris <jmorris (at) intercode.com.au>
     10  * 		    Harald Welte <laforge (at) gnumonks.org>
     11  * 		    Jozsef Kadlecsik <kadlec (at) blackhole.kfki.hu>
     12  *
     13  *	This program is free software; you can redistribute it and/or modify
     14  *	it under the terms of the GNU General Public License as published by
     15  *	the Free Software Foundation; either version 2 of the License, or
     16  *	(at your option) any later version.
     17  *
     18  *	This program is distributed in the hope that it will be useful,
     19  *	but WITHOUT ANY WARRANTY; without even the implied warranty of
     20  *	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
     21  *	GNU General Public License for more details.
     22  *
     23  *	You should have received a copy of the GNU General Public License
     24  *	along with this program; if not, write to the Free Software
     25  *	Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
     26  */
     27 
     28 #include <getopt.h>
     29 #include <string.h>
     30 #include <netdb.h>
     31 #include <errno.h>
     32 #include <stdbool.h>
     33 #include <stdio.h>
     34 #include <stdlib.h>
     35 #include <ctype.h>
     36 #include <stdarg.h>
     37 #include <limits.h>
     38 #include <unistd.h>
     39 #include <iptables.h>
     40 #include <xtables.h>
     41 #include <fcntl.h>
     42 #include <sys/utsname.h>
     43 #include "xshared.h"
     44 
     45 #ifndef TRUE
     46 #define TRUE 1
     47 #endif
     48 #ifndef FALSE
     49 #define FALSE 0
     50 #endif
     51 
     52 #define FMT_NUMERIC	0x0001
     53 #define FMT_NOCOUNTS	0x0002
     54 #define FMT_KILOMEGAGIGA 0x0004
     55 #define FMT_OPTIONS	0x0008
     56 #define FMT_NOTABLE	0x0010
     57 #define FMT_NOTARGET	0x0020
     58 #define FMT_VIA		0x0040
     59 #define FMT_NONEWLINE	0x0080
     60 #define FMT_LINENUMBERS 0x0100
     61 
     62 #define FMT_PRINT_RULE (FMT_NOCOUNTS | FMT_OPTIONS | FMT_VIA \
     63 			| FMT_NUMERIC | FMT_NOTABLE)
     64 #define FMT(tab,notab) ((format) & FMT_NOTABLE ? (notab) : (tab))
     65 
     66 
     67 #define CMD_NONE		0x0000U
     68 #define CMD_INSERT		0x0001U
     69 #define CMD_DELETE		0x0002U
     70 #define CMD_DELETE_NUM		0x0004U
     71 #define CMD_REPLACE		0x0008U
     72 #define CMD_APPEND		0x0010U
     73 #define CMD_LIST		0x0020U
     74 #define CMD_FLUSH		0x0040U
     75 #define CMD_ZERO		0x0080U
     76 #define CMD_NEW_CHAIN		0x0100U
     77 #define CMD_DELETE_CHAIN	0x0200U
     78 #define CMD_SET_POLICY		0x0400U
     79 #define CMD_RENAME_CHAIN	0x0800U
     80 #define CMD_LIST_RULES		0x1000U
     81 #define CMD_ZERO_NUM		0x2000U
     82 #define CMD_CHECK		0x4000U
     83 #define NUMBER_OF_CMD	16
     84 static const char cmdflags[] = { 'I', 'D', 'D', 'R', 'A', 'L', 'F', 'Z',
     85 				 'Z', 'N', 'X', 'P', 'E', 'S', 'C' };
     86 
     87 #define OPT_FRAGMENT    0x00800U
     88 #define NUMBER_OF_OPT	ARRAY_SIZE(optflags)
     89 static const char optflags[]
     90 = { 'n', 's', 'd', 'p', 'j', 'v', 'x', 'i', 'o', '0', 'c', 'f'};
     91 
     92 static struct option original_opts[] = {
     93 	{.name = "append",        .has_arg = 1, .val = 'A'},
     94 	{.name = "delete",        .has_arg = 1, .val = 'D'},
     95 	{.name = "check",         .has_arg = 1, .val = 'C'},
     96 	{.name = "insert",        .has_arg = 1, .val = 'I'},
     97 	{.name = "replace",       .has_arg = 1, .val = 'R'},
     98 	{.name = "list",          .has_arg = 2, .val = 'L'},
     99 	{.name = "list-rules",    .has_arg = 2, .val = 'S'},
    100 	{.name = "flush",         .has_arg = 2, .val = 'F'},
    101 	{.name = "zero",          .has_arg = 2, .val = 'Z'},
    102 	{.name = "new-chain",     .has_arg = 1, .val = 'N'},
    103 	{.name = "delete-chain",  .has_arg = 2, .val = 'X'},
    104 	{.name = "rename-chain",  .has_arg = 1, .val = 'E'},
    105 	{.name = "policy",        .has_arg = 1, .val = 'P'},
    106 	{.name = "source",        .has_arg = 1, .val = 's'},
    107 	{.name = "destination",   .has_arg = 1, .val = 'd'},
    108 	{.name = "src",           .has_arg = 1, .val = 's'}, /* synonym */
    109 	{.name = "dst",           .has_arg = 1, .val = 'd'}, /* synonym */
    110 	{.name = "protocol",      .has_arg = 1, .val = 'p'},
    111 	{.name = "in-interface",  .has_arg = 1, .val = 'i'},
    112 	{.name = "jump",          .has_arg = 1, .val = 'j'},
    113 	{.name = "table",         .has_arg = 1, .val = 't'},
    114 	{.name = "match",         .has_arg = 1, .val = 'm'},
    115 	{.name = "numeric",       .has_arg = 0, .val = 'n'},
    116 	{.name = "out-interface", .has_arg = 1, .val = 'o'},
    117 	{.name = "verbose",       .has_arg = 0, .val = 'v'},
    118 	{.name = "exact",         .has_arg = 0, .val = 'x'},
    119 	{.name = "fragments",     .has_arg = 0, .val = 'f'},
    120 	{.name = "version",       .has_arg = 0, .val = 'V'},
    121 	{.name = "help",          .has_arg = 2, .val = 'h'},
    122 	{.name = "line-numbers",  .has_arg = 0, .val = '0'},
    123 	{.name = "modprobe",      .has_arg = 1, .val = 'M'},
    124 	{.name = "set-counters",  .has_arg = 1, .val = 'c'},
    125 	{.name = "goto",          .has_arg = 1, .val = 'g'},
    126 	{.name = "ipv4",          .has_arg = 0, .val = '4'},
    127 	{.name = "ipv6",          .has_arg = 0, .val = '6'},
    128 	{NULL},
    129 };
    130 
    131 void iptables_exit_error(enum xtables_exittype status, const char *msg, ...) __attribute__((noreturn, format(printf,2,3)));
    132 
    133 struct xtables_globals iptables_globals = {
    134 	.option_offset = 0,
    135 	.program_version = IPTABLES_VERSION,
    136 	.orig_opts = original_opts,
    137 	.exit_err = iptables_exit_error,
    138 };
    139 
    140 /* Table of legal combinations of commands and options.  If any of the
    141  * given commands make an option legal, that option is legal (applies to
    142  * CMD_LIST and CMD_ZERO only).
    143  * Key:
    144  *  +  compulsory
    145  *  x  illegal
    146  *     optional
    147  */
    148 
    149 static const char commands_v_options[NUMBER_OF_CMD][NUMBER_OF_OPT] =
    150 /* Well, it's better than "Re: Linux vs FreeBSD" */
    151 {
    152 	/*     -n  -s  -d  -p  -j  -v  -x  -i  -o --line -c -f */
    153 /*INSERT*/    {'x',' ',' ',' ',' ',' ','x',' ',' ','x',' ',' '},
    154 /*DELETE*/    {'x',' ',' ',' ',' ',' ','x',' ',' ','x','x',' '},
    155 /*DELETE_NUM*/{'x','x','x','x','x',' ','x','x','x','x','x','x'},
    156 /*REPLACE*/   {'x',' ',' ',' ',' ',' ','x',' ',' ','x',' ',' '},
    157 /*APPEND*/    {'x',' ',' ',' ',' ',' ','x',' ',' ','x',' ',' '},
    158 /*LIST*/      {' ','x','x','x','x',' ',' ','x','x',' ','x','x'},
    159 /*FLUSH*/     {'x','x','x','x','x',' ','x','x','x','x','x','x'},
    160 /*ZERO*/      {'x','x','x','x','x',' ','x','x','x','x','x','x'},
    161 /*ZERO_NUM*/  {'x','x','x','x','x',' ','x','x','x','x','x','x'},
    162 /*NEW_CHAIN*/ {'x','x','x','x','x',' ','x','x','x','x','x','x'},
    163 /*DEL_CHAIN*/ {'x','x','x','x','x',' ','x','x','x','x','x','x'},
    164 /*SET_POLICY*/{'x','x','x','x','x',' ','x','x','x','x',' ','x'},
    165 /*RENAME*/    {'x','x','x','x','x',' ','x','x','x','x','x','x'},
    166 /*LIST_RULES*/{'x','x','x','x','x',' ','x','x','x','x','x','x'},
    167 /*CHECK*/     {'x',' ',' ',' ',' ',' ','x',' ',' ','x','x',' '},
    168 };
    169 
    170 static const int inverse_for_options[NUMBER_OF_OPT] =
    171 {
    172 /* -n */ 0,
    173 /* -s */ IPT_INV_SRCIP,
    174 /* -d */ IPT_INV_DSTIP,
    175 /* -p */ IPT_INV_PROTO,
    176 /* -j */ 0,
    177 /* -v */ 0,
    178 /* -x */ 0,
    179 /* -i */ IPT_INV_VIA_IN,
    180 /* -o */ IPT_INV_VIA_OUT,
    181 /* -f */ IPT_INV_FRAG,
    182 /*--line*/ 0,
    183 /* -c */ 0,
    184 };
    185 
    186 #define opts iptables_globals.opts
    187 #define prog_name iptables_globals.program_name
    188 #define prog_vers iptables_globals.program_version
    189 
    190 int kernel_version;
    191 
    192 /* Primitive headers... */
    193 /* defined in netinet/in.h */
    194 #if 0
    195 #ifndef IPPROTO_ESP
    196 #define IPPROTO_ESP 50
    197 #endif
    198 #ifndef IPPROTO_AH
    199 #define IPPROTO_AH 51
    200 #endif
    201 #endif
    202 
    203 enum {
    204 	IPT_DOTTED_ADDR = 0,
    205 	IPT_DOTTED_MASK
    206 };
    207 
    208 static void __attribute__((noreturn))
    209 exit_tryhelp(int status)
    210 {
    211 	if (line != -1)
    212 		fprintf(stderr, "Error occurred at line: %d\n", line);
    213 	fprintf(stderr, "Try `%s -h' or '%s --help' for more information.\n",
    214 			prog_name, prog_name);
    215 	xtables_free_opts(1);
    216 	exit(status);
    217 }
    218 
    219 static void
    220 exit_printhelp(const struct xtables_rule_match *matches)
    221 {
    222 	printf("%s v%s\n\n"
    223 "Usage: %s -[ACD] chain rule-specification [options]\n"
    224 "       %s -I chain [rulenum] rule-specification [options]\n"
    225 "       %s -R chain rulenum rule-specification [options]\n"
    226 "       %s -D chain rulenum [options]\n"
    227 "       %s -[LS] [chain [rulenum]] [options]\n"
    228 "       %s -[FZ] [chain] [options]\n"
    229 "       %s -[NX] chain\n"
    230 "       %s -E old-chain-name new-chain-name\n"
    231 "       %s -P chain target [options]\n"
    232 "       %s -h (print this help information)\n\n",
    233 	       prog_name, prog_vers, prog_name, prog_name,
    234 	       prog_name, prog_name, prog_name, prog_name,
    235 	       prog_name, prog_name, prog_name, prog_name);
    236 
    237 	printf(
    238 "Commands:\n"
    239 "Either long or short options are allowed.\n"
    240 "  --append  -A chain		Append to chain\n"
    241 "  --check   -C chain		Check for the existence of a rule\n"
    242 "  --delete  -D chain		Delete matching rule from chain\n"
    243 "  --delete  -D chain rulenum\n"
    244 "				Delete rule rulenum (1 = first) from chain\n"
    245 "  --insert  -I chain [rulenum]\n"
    246 "				Insert in chain as rulenum (default 1=first)\n"
    247 "  --replace -R chain rulenum\n"
    248 "				Replace rule rulenum (1 = first) in chain\n"
    249 "  --list    -L [chain [rulenum]]\n"
    250 "				List the rules in a chain or all chains\n"
    251 "  --list-rules -S [chain [rulenum]]\n"
    252 "				Print the rules in a chain or all chains\n"
    253 "  --flush   -F [chain]		Delete all rules in  chain or all chains\n"
    254 "  --zero    -Z [chain [rulenum]]\n"
    255 "				Zero counters in chain or all chains\n"
    256 "  --new     -N chain		Create a new user-defined chain\n"
    257 "  --delete-chain\n"
    258 "            -X [chain]		Delete a user-defined chain\n"
    259 "  --policy  -P chain target\n"
    260 "				Change policy on chain to target\n"
    261 "  --rename-chain\n"
    262 "            -E old-chain new-chain\n"
    263 "				Change chain name, (moving any references)\n"
    264 
    265 "Options:\n"
    266 "    --ipv4	-4		Nothing (line is ignored by ip6tables-restore)\n"
    267 "    --ipv6	-6		Error (line is ignored by iptables-restore)\n"
    268 "[!] --proto	-p proto	protocol: by number or name, eg. `tcp'\n"
    269 "[!] --source	-s address[/mask][...]\n"
    270 "				source specification\n"
    271 "[!] --destination -d address[/mask][...]\n"
    272 "				destination specification\n"
    273 "[!] --in-interface -i input name[+]\n"
    274 "				network interface name ([+] for wildcard)\n"
    275 " --jump	-j target\n"
    276 "				target for rule (may load target extension)\n"
    277 #ifdef IPT_F_GOTO
    278 "  --goto      -g chain\n"
    279 "                              jump to chain with no return\n"
    280 #endif
    281 "  --match	-m match\n"
    282 "				extended match (may load extension)\n"
    283 "  --numeric	-n		numeric output of addresses and ports\n"
    284 "[!] --out-interface -o output name[+]\n"
    285 "				network interface name ([+] for wildcard)\n"
    286 "  --table	-t table	table to manipulate (default: `filter')\n"
    287 "  --verbose	-v		verbose mode\n"
    288 "  --line-numbers		print line numbers when listing\n"
    289 "  --exact	-x		expand numbers (display exact values)\n"
    290 "[!] --fragment	-f		match second or further fragments only\n"
    291 "  --modprobe=<command>		try to insert modules using this command\n"
    292 "  --set-counters PKTS BYTES	set the counter during insert/append\n"
    293 "[!] --version	-V		print package version.\n");
    294 
    295 	print_extension_helps(xtables_targets, matches);
    296 	exit(0);
    297 }
    298 
    299 void
    300 iptables_exit_error(enum xtables_exittype status, const char *msg, ...)
    301 {
    302 	va_list args;
    303 
    304 	va_start(args, msg);
    305 	fprintf(stderr, "%s v%s: ", prog_name, prog_vers);
    306 	vfprintf(stderr, msg, args);
    307 	va_end(args);
    308 	fprintf(stderr, "\n");
    309 	if (status == PARAMETER_PROBLEM)
    310 		exit_tryhelp(status);
    311 	if (status == VERSION_PROBLEM)
    312 		fprintf(stderr,
    313 			"Perhaps iptables or your kernel needs to be upgraded.\n");
    314 	/* On error paths, make sure that we don't leak memory */
    315 	xtables_free_opts(1);
    316 	exit(status);
    317 }
    318 
    319 static void
    320 generic_opt_check(int command, int options)
    321 {
    322 	int i, j, legal = 0;
    323 
    324 	/* Check that commands are valid with options.  Complicated by the
    325 	 * fact that if an option is legal with *any* command given, it is
    326 	 * legal overall (ie. -z and -l).
    327 	 */
    328 	for (i = 0; i < NUMBER_OF_OPT; i++) {
    329 		legal = 0; /* -1 => illegal, 1 => legal, 0 => undecided. */
    330 
    331 		for (j = 0; j < NUMBER_OF_CMD; j++) {
    332 			if (!(command & (1<<j)))
    333 				continue;
    334 
    335 			if (!(options & (1<<i))) {
    336 				if (commands_v_options[j][i] == '+')
    337 					xtables_error(PARAMETER_PROBLEM,
    338 						   "You need to supply the `-%c' "
    339 						   "option for this command\n",
    340 						   optflags[i]);
    341 			} else {
    342 				if (commands_v_options[j][i] != 'x')
    343 					legal = 1;
    344 				else if (legal == 0)
    345 					legal = -1;
    346 			}
    347 		}
    348 		if (legal == -1)
    349 			xtables_error(PARAMETER_PROBLEM,
    350 				   "Illegal option `-%c' with this command\n",
    351 				   optflags[i]);
    352 	}
    353 }
    354 
    355 static char
    356 opt2char(int option)
    357 {
    358 	const char *ptr;
    359 	for (ptr = optflags; option > 1; option >>= 1, ptr++);
    360 
    361 	return *ptr;
    362 }
    363 
    364 static char
    365 cmd2char(int option)
    366 {
    367 	const char *ptr;
    368 	for (ptr = cmdflags; option > 1; option >>= 1, ptr++);
    369 
    370 	return *ptr;
    371 }
    372 
    373 static void
    374 add_command(unsigned int *cmd, const int newcmd, const int othercmds,
    375 	    int invert)
    376 {
    377 	if (invert)
    378 		xtables_error(PARAMETER_PROBLEM, "unexpected ! flag");
    379 	if (*cmd & (~othercmds))
    380 		xtables_error(PARAMETER_PROBLEM, "Cannot use -%c with -%c\n",
    381 			   cmd2char(newcmd), cmd2char(*cmd & (~othercmds)));
    382 	*cmd |= newcmd;
    383 }
    384 
    385 /*
    386  *	All functions starting with "parse" should succeed, otherwise
    387  *	the program fails.
    388  *	Most routines return pointers to static data that may change
    389  *	between calls to the same or other routines with a few exceptions:
    390  *	"host_to_addr", "parse_hostnetwork", and "parse_hostnetworkmask"
    391  *	return global static data.
    392 */
    393 
    394 /* Christophe Burki wants `-p 6' to imply `-m tcp'.  */
    395 /* Can't be zero. */
    396 static int
    397 parse_rulenumber(const char *rule)
    398 {
    399 	unsigned int rulenum;
    400 
    401 	if (!xtables_strtoui(rule, NULL, &rulenum, 1, INT_MAX))
    402 		xtables_error(PARAMETER_PROBLEM,
    403 			   "Invalid rule number `%s'", rule);
    404 
    405 	return rulenum;
    406 }
    407 
    408 static const char *
    409 parse_target(const char *targetname)
    410 {
    411 	const char *ptr;
    412 
    413 	if (strlen(targetname) < 1)
    414 		xtables_error(PARAMETER_PROBLEM,
    415 			   "Invalid target name (too short)");
    416 
    417 	if (strlen(targetname) >= XT_EXTENSION_MAXNAMELEN)
    418 		xtables_error(PARAMETER_PROBLEM,
    419 			   "Invalid target name `%s' (%u chars max)",
    420 			   targetname, XT_EXTENSION_MAXNAMELEN - 1);
    421 
    422 	for (ptr = targetname; *ptr; ptr++)
    423 		if (isspace(*ptr))
    424 			xtables_error(PARAMETER_PROBLEM,
    425 				   "Invalid target name `%s'", targetname);
    426 	return targetname;
    427 }
    428 
    429 static void
    430 set_option(unsigned int *options, unsigned int option, uint8_t *invflg,
    431 	   int invert)
    432 {
    433 	if (*options & option)
    434 		xtables_error(PARAMETER_PROBLEM, "multiple -%c flags not allowed",
    435 			   opt2char(option));
    436 	*options |= option;
    437 
    438 	if (invert) {
    439 		unsigned int i;
    440 		for (i = 0; 1 << i != option; i++);
    441 
    442 		if (!inverse_for_options[i])
    443 			xtables_error(PARAMETER_PROBLEM,
    444 				   "cannot have ! before -%c",
    445 				   opt2char(option));
    446 		*invflg |= inverse_for_options[i];
    447 	}
    448 }
    449 
    450 static void
    451 print_num(uint64_t number, unsigned int format)
    452 {
    453 	if (format & FMT_KILOMEGAGIGA) {
    454 		if (number > 99999) {
    455 			number = (number + 500) / 1000;
    456 			if (number > 9999) {
    457 				number = (number + 500) / 1000;
    458 				if (number > 9999) {
    459 					number = (number + 500) / 1000;
    460 					if (number > 9999) {
    461 						number = (number + 500) / 1000;
    462 						printf(FMT("%4lluT ","%lluT "), (unsigned long long)number);
    463 					}
    464 					else printf(FMT("%4lluG ","%lluG "), (unsigned long long)number);
    465 				}
    466 				else printf(FMT("%4lluM ","%lluM "), (unsigned long long)number);
    467 			} else
    468 				printf(FMT("%4lluK ","%lluK "), (unsigned long long)number);
    469 		} else
    470 			printf(FMT("%5llu ","%llu "), (unsigned long long)number);
    471 	} else
    472 		printf(FMT("%8llu ","%llu "), (unsigned long long)number);
    473 }
    474 
    475 
    476 static void
    477 print_header(unsigned int format, const char *chain, struct iptc_handle *handle)
    478 {
    479 	struct ipt_counters counters;
    480 	const char *pol = iptc_get_policy(chain, &counters, handle);
    481 	printf("Chain %s", chain);
    482 	if (pol) {
    483 		printf(" (policy %s", pol);
    484 		if (!(format & FMT_NOCOUNTS)) {
    485 			fputc(' ', stdout);
    486 			print_num(counters.pcnt, (format|FMT_NOTABLE));
    487 			fputs("packets, ", stdout);
    488 			print_num(counters.bcnt, (format|FMT_NOTABLE));
    489 			fputs("bytes", stdout);
    490 		}
    491 		printf(")\n");
    492 	} else {
    493 		unsigned int refs;
    494 		if (!iptc_get_references(&refs, chain, handle))
    495 			printf(" (ERROR obtaining refs)\n");
    496 		else
    497 			printf(" (%u references)\n", refs);
    498 	}
    499 
    500 	if (format & FMT_LINENUMBERS)
    501 		printf(FMT("%-4s ", "%s "), "num");
    502 	if (!(format & FMT_NOCOUNTS)) {
    503 		if (format & FMT_KILOMEGAGIGA) {
    504 			printf(FMT("%5s ","%s "), "pkts");
    505 			printf(FMT("%5s ","%s "), "bytes");
    506 		} else {
    507 			printf(FMT("%8s ","%s "), "pkts");
    508 			printf(FMT("%10s ","%s "), "bytes");
    509 		}
    510 	}
    511 	if (!(format & FMT_NOTARGET))
    512 		printf(FMT("%-9s ","%s "), "target");
    513 	fputs(" prot ", stdout);
    514 	if (format & FMT_OPTIONS)
    515 		fputs("opt", stdout);
    516 	if (format & FMT_VIA) {
    517 		printf(FMT(" %-6s ","%s "), "in");
    518 		printf(FMT("%-6s ","%s "), "out");
    519 	}
    520 	printf(FMT(" %-19s ","%s "), "source");
    521 	printf(FMT(" %-19s "," %s "), "destination");
    522 	printf("\n");
    523 }
    524 
    525 
    526 static int
    527 print_match(const struct ipt_entry_match *m,
    528 	    const struct ipt_ip *ip,
    529 	    int numeric)
    530 {
    531 	const struct xtables_match *match =
    532 		xtables_find_match(m->u.user.name, XTF_TRY_LOAD, NULL);
    533 
    534 	if (match) {
    535 		if (match->print)
    536 			match->print(ip, m, numeric);
    537 		else
    538 			printf("%s ", match->name);
    539 	} else {
    540 		if (m->u.user.name[0])
    541 			printf("UNKNOWN match `%s' ", m->u.user.name);
    542 	}
    543 	/* Don't stop iterating. */
    544 	return 0;
    545 }
    546 
    547 /* e is called `fw' here for historical reasons */
    548 static void
    549 print_firewall(const struct ipt_entry *fw,
    550 	       const char *targname,
    551 	       unsigned int num,
    552 	       unsigned int format,
    553 	       struct iptc_handle *const handle)
    554 {
    555 	const struct xtables_target *target = NULL;
    556 	const struct ipt_entry_target *t;
    557 	uint8_t flags;
    558 	char buf[BUFSIZ];
    559 
    560 	if (!iptc_is_chain(targname, handle))
    561 		target = xtables_find_target(targname, XTF_TRY_LOAD);
    562 	else
    563 		target = xtables_find_target(IPT_STANDARD_TARGET,
    564 		         XTF_LOAD_MUST_SUCCEED);
    565 
    566 	t = ipt_get_target((struct ipt_entry *)fw);
    567 	flags = fw->ip.flags;
    568 
    569 	if (format & FMT_LINENUMBERS)
    570 		printf(FMT("%-4u ", "%u "), num);
    571 
    572 	if (!(format & FMT_NOCOUNTS)) {
    573 		print_num(fw->counters.pcnt, format);
    574 		print_num(fw->counters.bcnt, format);
    575 	}
    576 
    577 	if (!(format & FMT_NOTARGET))
    578 		printf(FMT("%-9s ", "%s "), targname);
    579 
    580 	fputc(fw->ip.invflags & IPT_INV_PROTO ? '!' : ' ', stdout);
    581 	{
    582 		const char *pname = proto_to_name(fw->ip.proto, format&FMT_NUMERIC);
    583 		if (pname)
    584 			printf(FMT("%-5s", "%s "), pname);
    585 		else
    586 			printf(FMT("%-5hu", "%hu "), fw->ip.proto);
    587 	}
    588 
    589 	if (format & FMT_OPTIONS) {
    590 		if (format & FMT_NOTABLE)
    591 			fputs("opt ", stdout);
    592 		fputc(fw->ip.invflags & IPT_INV_FRAG ? '!' : '-', stdout);
    593 		fputc(flags & IPT_F_FRAG ? 'f' : '-', stdout);
    594 		fputc(' ', stdout);
    595 	}
    596 
    597 	if (format & FMT_VIA) {
    598 		char iface[IFNAMSIZ+2];
    599 
    600 		if (fw->ip.invflags & IPT_INV_VIA_IN) {
    601 			iface[0] = '!';
    602 			iface[1] = '\0';
    603 		}
    604 		else iface[0] = '\0';
    605 
    606 		if (fw->ip.iniface[0] != '\0') {
    607 			strcat(iface, fw->ip.iniface);
    608 		}
    609 		else if (format & FMT_NUMERIC) strcat(iface, "*");
    610 		else strcat(iface, "any");
    611 		printf(FMT(" %-6s ","in %s "), iface);
    612 
    613 		if (fw->ip.invflags & IPT_INV_VIA_OUT) {
    614 			iface[0] = '!';
    615 			iface[1] = '\0';
    616 		}
    617 		else iface[0] = '\0';
    618 
    619 		if (fw->ip.outiface[0] != '\0') {
    620 			strcat(iface, fw->ip.outiface);
    621 		}
    622 		else if (format & FMT_NUMERIC) strcat(iface, "*");
    623 		else strcat(iface, "any");
    624 		printf(FMT("%-6s ","out %s "), iface);
    625 	}
    626 
    627 	fputc(fw->ip.invflags & IPT_INV_SRCIP ? '!' : ' ', stdout);
    628 	if (fw->ip.smsk.s_addr == 0L && !(format & FMT_NUMERIC))
    629 		printf(FMT("%-19s ","%s "), "anywhere");
    630 	else {
    631 		if (format & FMT_NUMERIC)
    632 			strcpy(buf, xtables_ipaddr_to_numeric(&fw->ip.src));
    633 		else
    634 			strcpy(buf, xtables_ipaddr_to_anyname(&fw->ip.src));
    635 		strcat(buf, xtables_ipmask_to_numeric(&fw->ip.smsk));
    636 		printf(FMT("%-19s ","%s "), buf);
    637 	}
    638 
    639 	fputc(fw->ip.invflags & IPT_INV_DSTIP ? '!' : ' ', stdout);
    640 	if (fw->ip.dmsk.s_addr == 0L && !(format & FMT_NUMERIC))
    641 		printf(FMT("%-19s ","-> %s"), "anywhere");
    642 	else {
    643 		if (format & FMT_NUMERIC)
    644 			strcpy(buf, xtables_ipaddr_to_numeric(&fw->ip.dst));
    645 		else
    646 			strcpy(buf, xtables_ipaddr_to_anyname(&fw->ip.dst));
    647 		strcat(buf, xtables_ipmask_to_numeric(&fw->ip.dmsk));
    648 		printf(FMT("%-19s ","-> %s"), buf);
    649 	}
    650 
    651 	if (format & FMT_NOTABLE)
    652 		fputs("  ", stdout);
    653 
    654 #ifdef IPT_F_GOTO
    655 	if(fw->ip.flags & IPT_F_GOTO)
    656 		printf("[goto] ");
    657 #endif
    658 
    659 	IPT_MATCH_ITERATE(fw, print_match, &fw->ip, format & FMT_NUMERIC);
    660 
    661 	if (target) {
    662 		if (target->print)
    663 			/* Print the target information. */
    664 			target->print(&fw->ip, t, format & FMT_NUMERIC);
    665 	} else if (t->u.target_size != sizeof(*t))
    666 		printf("[%u bytes of unknown target data] ",
    667 		       (unsigned int)(t->u.target_size - sizeof(*t)));
    668 
    669 	if (!(format & FMT_NONEWLINE))
    670 		fputc('\n', stdout);
    671 }
    672 
    673 static void
    674 print_firewall_line(const struct ipt_entry *fw,
    675 		    struct iptc_handle *const h)
    676 {
    677 	struct ipt_entry_target *t;
    678 
    679 	t = ipt_get_target((struct ipt_entry *)fw);
    680 	print_firewall(fw, t->u.user.name, 0, FMT_PRINT_RULE, h);
    681 }
    682 
    683 static int
    684 append_entry(const ipt_chainlabel chain,
    685 	     struct ipt_entry *fw,
    686 	     unsigned int nsaddrs,
    687 	     const struct in_addr saddrs[],
    688 	     const struct in_addr smasks[],
    689 	     unsigned int ndaddrs,
    690 	     const struct in_addr daddrs[],
    691 	     const struct in_addr dmasks[],
    692 	     int verbose,
    693 	     struct iptc_handle *handle)
    694 {
    695 	unsigned int i, j;
    696 	int ret = 1;
    697 
    698 	for (i = 0; i < nsaddrs; i++) {
    699 		fw->ip.src.s_addr = saddrs[i].s_addr;
    700 		fw->ip.smsk.s_addr = smasks[i].s_addr;
    701 		for (j = 0; j < ndaddrs; j++) {
    702 			fw->ip.dst.s_addr = daddrs[j].s_addr;
    703 			fw->ip.dmsk.s_addr = dmasks[j].s_addr;
    704 			if (verbose)
    705 				print_firewall_line(fw, handle);
    706 			ret &= iptc_append_entry(chain, fw, handle);
    707 		}
    708 	}
    709 
    710 	return ret;
    711 }
    712 
    713 static int
    714 replace_entry(const ipt_chainlabel chain,
    715 	      struct ipt_entry *fw,
    716 	      unsigned int rulenum,
    717 	      const struct in_addr *saddr, const struct in_addr *smask,
    718 	      const struct in_addr *daddr, const struct in_addr *dmask,
    719 	      int verbose,
    720 	      struct iptc_handle *handle)
    721 {
    722 	fw->ip.src.s_addr = saddr->s_addr;
    723 	fw->ip.dst.s_addr = daddr->s_addr;
    724 	fw->ip.smsk.s_addr = smask->s_addr;
    725 	fw->ip.dmsk.s_addr = dmask->s_addr;
    726 
    727 	if (verbose)
    728 		print_firewall_line(fw, handle);
    729 	return iptc_replace_entry(chain, fw, rulenum, handle);
    730 }
    731 
    732 static int
    733 insert_entry(const ipt_chainlabel chain,
    734 	     struct ipt_entry *fw,
    735 	     unsigned int rulenum,
    736 	     unsigned int nsaddrs,
    737 	     const struct in_addr saddrs[],
    738 	     const struct in_addr smasks[],
    739 	     unsigned int ndaddrs,
    740 	     const struct in_addr daddrs[],
    741 	     const struct in_addr dmasks[],
    742 	     int verbose,
    743 	     struct iptc_handle *handle)
    744 {
    745 	unsigned int i, j;
    746 	int ret = 1;
    747 
    748 	for (i = 0; i < nsaddrs; i++) {
    749 		fw->ip.src.s_addr = saddrs[i].s_addr;
    750 		fw->ip.smsk.s_addr = smasks[i].s_addr;
    751 		for (j = 0; j < ndaddrs; j++) {
    752 			fw->ip.dst.s_addr = daddrs[j].s_addr;
    753 			fw->ip.dmsk.s_addr = dmasks[j].s_addr;
    754 			if (verbose)
    755 				print_firewall_line(fw, handle);
    756 			ret &= iptc_insert_entry(chain, fw, rulenum, handle);
    757 		}
    758 	}
    759 
    760 	return ret;
    761 }
    762 
    763 static unsigned char *
    764 make_delete_mask(const struct xtables_rule_match *matches,
    765 		 const struct xtables_target *target)
    766 {
    767 	/* Establish mask for comparison */
    768 	unsigned int size;
    769 	const struct xtables_rule_match *matchp;
    770 	unsigned char *mask, *mptr;
    771 
    772 	size = sizeof(struct ipt_entry);
    773 	for (matchp = matches; matchp; matchp = matchp->next)
    774 		size += XT_ALIGN(sizeof(struct ipt_entry_match)) + matchp->match->size;
    775 
    776 	mask = xtables_calloc(1, size
    777 			 + XT_ALIGN(sizeof(struct ipt_entry_target))
    778 			 + target->size);
    779 
    780 	memset(mask, 0xFF, sizeof(struct ipt_entry));
    781 	mptr = mask + sizeof(struct ipt_entry);
    782 
    783 	for (matchp = matches; matchp; matchp = matchp->next) {
    784 		memset(mptr, 0xFF,
    785 		       XT_ALIGN(sizeof(struct ipt_entry_match))
    786 		       + matchp->match->userspacesize);
    787 		mptr += XT_ALIGN(sizeof(struct ipt_entry_match)) + matchp->match->size;
    788 	}
    789 
    790 	memset(mptr, 0xFF,
    791 	       XT_ALIGN(sizeof(struct ipt_entry_target))
    792 	       + target->userspacesize);
    793 
    794 	return mask;
    795 }
    796 
    797 static int
    798 delete_entry(const ipt_chainlabel chain,
    799 	     struct ipt_entry *fw,
    800 	     unsigned int nsaddrs,
    801 	     const struct in_addr saddrs[],
    802 	     const struct in_addr smasks[],
    803 	     unsigned int ndaddrs,
    804 	     const struct in_addr daddrs[],
    805 	     const struct in_addr dmasks[],
    806 	     int verbose,
    807 	     struct iptc_handle *handle,
    808 	     struct xtables_rule_match *matches,
    809 	     const struct xtables_target *target)
    810 {
    811 	unsigned int i, j;
    812 	int ret = 1;
    813 	unsigned char *mask;
    814 
    815 	mask = make_delete_mask(matches, target);
    816 	for (i = 0; i < nsaddrs; i++) {
    817 		fw->ip.src.s_addr = saddrs[i].s_addr;
    818 		fw->ip.smsk.s_addr = smasks[i].s_addr;
    819 		for (j = 0; j < ndaddrs; j++) {
    820 			fw->ip.dst.s_addr = daddrs[j].s_addr;
    821 			fw->ip.dmsk.s_addr = dmasks[j].s_addr;
    822 			if (verbose)
    823 				print_firewall_line(fw, handle);
    824 			ret &= iptc_delete_entry(chain, fw, mask, handle);
    825 		}
    826 	}
    827 	free(mask);
    828 
    829 	return ret;
    830 }
    831 
    832 static int
    833 check_entry(const ipt_chainlabel chain, struct ipt_entry *fw,
    834 	    unsigned int nsaddrs, const struct in_addr *saddrs,
    835 	    const struct in_addr *smasks, unsigned int ndaddrs,
    836 	    const struct in_addr *daddrs, const struct in_addr *dmasks,
    837 	    bool verbose, struct iptc_handle *handle,
    838 	    struct xtables_rule_match *matches,
    839 	    const struct xtables_target *target)
    840 {
    841 	unsigned int i, j;
    842 	int ret = 1;
    843 	unsigned char *mask;
    844 
    845 	mask = make_delete_mask(matches, target);
    846 	for (i = 0; i < nsaddrs; i++) {
    847 		fw->ip.src.s_addr = saddrs[i].s_addr;
    848 		fw->ip.smsk.s_addr = smasks[i].s_addr;
    849 		for (j = 0; j < ndaddrs; j++) {
    850 			fw->ip.dst.s_addr = daddrs[j].s_addr;
    851 			fw->ip.dmsk.s_addr = dmasks[j].s_addr;
    852 			if (verbose)
    853 				print_firewall_line(fw, handle);
    854 			ret &= iptc_check_entry(chain, fw, mask, handle);
    855 		}
    856 	}
    857 
    858 	free(mask);
    859 	return ret;
    860 }
    861 
    862 int
    863 for_each_chain4(int (*fn)(const ipt_chainlabel, int, struct iptc_handle *),
    864 	       int verbose, int builtinstoo, struct iptc_handle *handle)
    865 {
    866         int ret = 1;
    867 	const char *chain;
    868 	char *chains;
    869 	unsigned int i, chaincount = 0;
    870 
    871 	chain = iptc_first_chain(handle);
    872 	while (chain) {
    873 		chaincount++;
    874 		chain = iptc_next_chain(handle);
    875         }
    876 
    877 	chains = xtables_malloc(sizeof(ipt_chainlabel) * chaincount);
    878 	i = 0;
    879 	chain = iptc_first_chain(handle);
    880 	while (chain) {
    881 		strcpy(chains + i*sizeof(ipt_chainlabel), chain);
    882 		i++;
    883 		chain = iptc_next_chain(handle);
    884         }
    885 
    886 	for (i = 0; i < chaincount; i++) {
    887 		if (!builtinstoo
    888 		    && iptc_builtin(chains + i*sizeof(ipt_chainlabel),
    889 				    handle) == 1)
    890 			continue;
    891 	        ret &= fn(chains + i*sizeof(ipt_chainlabel), verbose, handle);
    892 	}
    893 
    894 	free(chains);
    895         return ret;
    896 }
    897 
    898 int
    899 flush_entries4(const ipt_chainlabel chain, int verbose,
    900 	      struct iptc_handle *handle)
    901 {
    902 	if (!chain)
    903 		return for_each_chain4(flush_entries4, verbose, 1, handle);
    904 
    905 	if (verbose)
    906 		fprintf(stdout, "Flushing chain `%s'\n", chain);
    907 	return iptc_flush_entries(chain, handle);
    908 }
    909 
    910 static int
    911 zero_entries(const ipt_chainlabel chain, int verbose,
    912 	     struct iptc_handle *handle)
    913 {
    914 	if (!chain)
    915 		return for_each_chain4(zero_entries, verbose, 1, handle);
    916 
    917 	if (verbose)
    918 		fprintf(stdout, "Zeroing chain `%s'\n", chain);
    919 	return iptc_zero_entries(chain, handle);
    920 }
    921 
    922 int
    923 delete_chain4(const ipt_chainlabel chain, int verbose,
    924 	     struct iptc_handle *handle)
    925 {
    926 	if (!chain)
    927 		return for_each_chain4(delete_chain4, verbose, 0, handle);
    928 
    929 	if (verbose)
    930 		fprintf(stdout, "Deleting chain `%s'\n", chain);
    931 	return iptc_delete_chain(chain, handle);
    932 }
    933 
    934 static int
    935 list_entries(const ipt_chainlabel chain, int rulenum, int verbose, int numeric,
    936 	     int expanded, int linenumbers, struct iptc_handle *handle)
    937 {
    938 	int found = 0;
    939 	unsigned int format;
    940 	const char *this;
    941 
    942 	format = FMT_OPTIONS;
    943 	if (!verbose)
    944 		format |= FMT_NOCOUNTS;
    945 	else
    946 		format |= FMT_VIA;
    947 
    948 	if (numeric)
    949 		format |= FMT_NUMERIC;
    950 
    951 	if (!expanded)
    952 		format |= FMT_KILOMEGAGIGA;
    953 
    954 	if (linenumbers)
    955 		format |= FMT_LINENUMBERS;
    956 
    957 	for (this = iptc_first_chain(handle);
    958 	     this;
    959 	     this = iptc_next_chain(handle)) {
    960 		const struct ipt_entry *i;
    961 		unsigned int num;
    962 
    963 		if (chain && strcmp(chain, this) != 0)
    964 			continue;
    965 
    966 		if (found) printf("\n");
    967 
    968 		if (!rulenum)
    969 			print_header(format, this, handle);
    970 		i = iptc_first_rule(this, handle);
    971 
    972 		num = 0;
    973 		while (i) {
    974 			num++;
    975 			if (!rulenum || num == rulenum)
    976 				print_firewall(i,
    977 					       iptc_get_target(i, handle),
    978 					       num,
    979 					       format,
    980 					       handle);
    981 			i = iptc_next_rule(i, handle);
    982 		}
    983 		found = 1;
    984 	}
    985 
    986 	errno = ENOENT;
    987 	return found;
    988 }
    989 
    990 static void print_proto(uint16_t proto, int invert)
    991 {
    992 	if (proto) {
    993 		unsigned int i;
    994 		const char *invertstr = invert ? " !" : "";
    995 
    996 		const struct protoent *pent = getprotobynumber(proto);
    997 		if (pent) {
    998 			printf("%s -p %s", invertstr, pent->p_name);
    999 			return;
   1000 		}
   1001 
   1002 		for (i = 0; xtables_chain_protos[i].name != NULL; ++i)
   1003 			if (xtables_chain_protos[i].num == proto) {
   1004 				printf("%s -p %s",
   1005 				       invertstr, xtables_chain_protos[i].name);
   1006 				return;
   1007 			}
   1008 
   1009 		printf("%s -p %u", invertstr, proto);
   1010 	}
   1011 }
   1012 
   1013 #define IP_PARTS_NATIVE(n)			\
   1014 (unsigned int)((n)>>24)&0xFF,			\
   1015 (unsigned int)((n)>>16)&0xFF,			\
   1016 (unsigned int)((n)>>8)&0xFF,			\
   1017 (unsigned int)((n)&0xFF)
   1018 
   1019 #define IP_PARTS(n) IP_PARTS_NATIVE(ntohl(n))
   1020 
   1021 /* This assumes that mask is contiguous, and byte-bounded. */
   1022 static void
   1023 print_iface(char letter, const char *iface, const unsigned char *mask,
   1024 	    int invert)
   1025 {
   1026 	unsigned int i;
   1027 
   1028 	if (mask[0] == 0)
   1029 		return;
   1030 
   1031 	printf("%s -%c ", invert ? " !" : "", letter);
   1032 
   1033 	for (i = 0; i < IFNAMSIZ; i++) {
   1034 		if (mask[i] != 0) {
   1035 			if (iface[i] != '\0')
   1036 				printf("%c", iface[i]);
   1037 		} else {
   1038 			/* we can access iface[i-1] here, because
   1039 			 * a few lines above we make sure that mask[0] != 0 */
   1040 			if (iface[i-1] != '\0')
   1041 				printf("+");
   1042 			break;
   1043 		}
   1044 	}
   1045 }
   1046 
   1047 static int print_match_save(const struct ipt_entry_match *e,
   1048 			const struct ipt_ip *ip)
   1049 {
   1050 	const struct xtables_match *match =
   1051 		xtables_find_match(e->u.user.name, XTF_TRY_LOAD, NULL);
   1052 
   1053 	if (match) {
   1054 		printf(" -m %s", e->u.user.name);
   1055 
   1056 		/* some matches don't provide a save function */
   1057 		if (match->save)
   1058 			match->save(ip, e);
   1059 	} else {
   1060 		if (e->u.match_size) {
   1061 			fprintf(stderr,
   1062 				"Can't find library for match `%s'\n",
   1063 				e->u.user.name);
   1064 			exit(1);
   1065 		}
   1066 	}
   1067 	return 0;
   1068 }
   1069 
   1070 /* print a given ip including mask if neccessary */
   1071 static void print_ip(const char *prefix, uint32_t ip,
   1072 		     uint32_t mask, int invert)
   1073 {
   1074 	uint32_t bits, hmask = ntohl(mask);
   1075 	int i;
   1076 
   1077 	if (!mask && !ip && !invert)
   1078 		return;
   1079 
   1080 	printf("%s %s %u.%u.%u.%u",
   1081 		invert ? " !" : "",
   1082 		prefix,
   1083 		IP_PARTS(ip));
   1084 
   1085 	if (mask == 0xFFFFFFFFU) {
   1086 		printf("/32");
   1087 		return;
   1088 	}
   1089 
   1090 	i    = 32;
   1091 	bits = 0xFFFFFFFEU;
   1092 	while (--i >= 0 && hmask != bits)
   1093 		bits <<= 1;
   1094 	if (i >= 0)
   1095 		printf("/%u", i);
   1096 	else
   1097 		printf("/%u.%u.%u.%u", IP_PARTS(mask));
   1098 }
   1099 
   1100 /* We want this to be readable, so only print out neccessary fields.
   1101  * Because that's the kind of world I want to live in.  */
   1102 void print_rule4(const struct ipt_entry *e,
   1103 		struct iptc_handle *h, const char *chain, int counters)
   1104 {
   1105 	const struct ipt_entry_target *t;
   1106 	const char *target_name;
   1107 
   1108 	/* print counters for iptables-save */
   1109 	if (counters > 0)
   1110 		printf("[%llu:%llu] ", (unsigned long long)e->counters.pcnt, (unsigned long long)e->counters.bcnt);
   1111 
   1112 	/* print chain name */
   1113 	printf("-A %s", chain);
   1114 
   1115 	/* Print IP part. */
   1116 	print_ip("-s", e->ip.src.s_addr,e->ip.smsk.s_addr,
   1117 			e->ip.invflags & IPT_INV_SRCIP);
   1118 
   1119 	print_ip("-d", e->ip.dst.s_addr, e->ip.dmsk.s_addr,
   1120 			e->ip.invflags & IPT_INV_DSTIP);
   1121 
   1122 	print_iface('i', e->ip.iniface, e->ip.iniface_mask,
   1123 		    e->ip.invflags & IPT_INV_VIA_IN);
   1124 
   1125 	print_iface('o', e->ip.outiface, e->ip.outiface_mask,
   1126 		    e->ip.invflags & IPT_INV_VIA_OUT);
   1127 
   1128 	print_proto(e->ip.proto, e->ip.invflags & IPT_INV_PROTO);
   1129 
   1130 	if (e->ip.flags & IPT_F_FRAG)
   1131 		printf("%s -f",
   1132 		       e->ip.invflags & IPT_INV_FRAG ? " !" : "");
   1133 
   1134 	/* Print matchinfo part */
   1135 	if (e->target_offset) {
   1136 		IPT_MATCH_ITERATE(e, print_match_save, &e->ip);
   1137 	}
   1138 
   1139 	/* print counters for iptables -R */
   1140 	if (counters < 0)
   1141 		printf(" -c %llu %llu", (unsigned long long)e->counters.pcnt, (unsigned long long)e->counters.bcnt);
   1142 
   1143 	/* Print target name */
   1144 	target_name = iptc_get_target(e, h);
   1145 	if (target_name && (*target_name != '\0'))
   1146 #ifdef IPT_F_GOTO
   1147 		printf(" -%c %s", e->ip.flags & IPT_F_GOTO ? 'g' : 'j', target_name);
   1148 #else
   1149 		printf(" -j %s", target_name);
   1150 #endif
   1151 
   1152 	/* Print targinfo part */
   1153 	t = ipt_get_target((struct ipt_entry *)e);
   1154 	if (t->u.user.name[0]) {
   1155 		const struct xtables_target *target =
   1156 			xtables_find_target(t->u.user.name, XTF_TRY_LOAD);
   1157 
   1158 		if (!target) {
   1159 			fprintf(stderr, "Can't find library for target `%s'\n",
   1160 				t->u.user.name);
   1161 			exit(1);
   1162 		}
   1163 
   1164 		if (target->save)
   1165 			target->save(&e->ip, t);
   1166 		else {
   1167 			/* If the target size is greater than ipt_entry_target
   1168 			 * there is something to be saved, we just don't know
   1169 			 * how to print it */
   1170 			if (t->u.target_size !=
   1171 			    sizeof(struct ipt_entry_target)) {
   1172 				fprintf(stderr, "Target `%s' is missing "
   1173 						"save function\n",
   1174 					t->u.user.name);
   1175 				exit(1);
   1176 			}
   1177 		}
   1178 	}
   1179 	printf("\n");
   1180 }
   1181 
   1182 static int
   1183 list_rules(const ipt_chainlabel chain, int rulenum, int counters,
   1184 	     struct iptc_handle *handle)
   1185 {
   1186 	const char *this = NULL;
   1187 	int found = 0;
   1188 
   1189 	if (counters)
   1190 	    counters = -1;		/* iptables -c format */
   1191 
   1192 	/* Dump out chain names first,
   1193 	 * thereby preventing dependency conflicts */
   1194 	if (!rulenum) for (this = iptc_first_chain(handle);
   1195 	     this;
   1196 	     this = iptc_next_chain(handle)) {
   1197 		if (chain && strcmp(this, chain) != 0)
   1198 			continue;
   1199 
   1200 		if (iptc_builtin(this, handle)) {
   1201 			struct ipt_counters count;
   1202 			printf("-P %s %s", this, iptc_get_policy(this, &count, handle));
   1203 			if (counters)
   1204 			    printf(" -c %llu %llu", (unsigned long long)count.pcnt, (unsigned long long)count.bcnt);
   1205 			printf("\n");
   1206 		} else {
   1207 			printf("-N %s\n", this);
   1208 		}
   1209 	}
   1210 
   1211 	for (this = iptc_first_chain(handle);
   1212 	     this;
   1213 	     this = iptc_next_chain(handle)) {
   1214 		const struct ipt_entry *e;
   1215 		int num = 0;
   1216 
   1217 		if (chain && strcmp(this, chain) != 0)
   1218 			continue;
   1219 
   1220 		/* Dump out rules */
   1221 		e = iptc_first_rule(this, handle);
   1222 		while(e) {
   1223 			num++;
   1224 			if (!rulenum || num == rulenum)
   1225 			    print_rule4(e, handle, this, counters);
   1226 			e = iptc_next_rule(e, handle);
   1227 		}
   1228 		found = 1;
   1229 	}
   1230 
   1231 	errno = ENOENT;
   1232 	return found;
   1233 }
   1234 
   1235 static struct ipt_entry *
   1236 generate_entry(const struct ipt_entry *fw,
   1237 	       struct xtables_rule_match *matches,
   1238 	       struct ipt_entry_target *target)
   1239 {
   1240 	unsigned int size;
   1241 	struct xtables_rule_match *matchp;
   1242 	struct ipt_entry *e;
   1243 
   1244 	size = sizeof(struct ipt_entry);
   1245 	for (matchp = matches; matchp; matchp = matchp->next)
   1246 		size += matchp->match->m->u.match_size;
   1247 
   1248 	e = xtables_malloc(size + target->u.target_size);
   1249 	*e = *fw;
   1250 	e->target_offset = size;
   1251 	e->next_offset = size + target->u.target_size;
   1252 
   1253 	size = 0;
   1254 	for (matchp = matches; matchp; matchp = matchp->next) {
   1255 		memcpy(e->elems + size, matchp->match->m, matchp->match->m->u.match_size);
   1256 		size += matchp->match->m->u.match_size;
   1257 	}
   1258 	memcpy(e->elems + size, target, target->u.target_size);
   1259 
   1260 	return e;
   1261 }
   1262 
   1263 static void clear_rule_matches(struct xtables_rule_match **matches)
   1264 {
   1265 	struct xtables_rule_match *matchp, *tmp;
   1266 
   1267 	for (matchp = *matches; matchp;) {
   1268 		tmp = matchp->next;
   1269 		if (matchp->match->m) {
   1270 			free(matchp->match->m);
   1271 			matchp->match->m = NULL;
   1272 		}
   1273 		if (matchp->match == matchp->match->next) {
   1274 			free(matchp->match);
   1275 			matchp->match = NULL;
   1276 		}
   1277 		free(matchp);
   1278 		matchp = tmp;
   1279 	}
   1280 
   1281 	*matches = NULL;
   1282 }
   1283 
   1284 void
   1285 get_kernel_version(void) {
   1286 	static struct utsname uts;
   1287 	int x = 0, y = 0, z = 0;
   1288 
   1289 	if (uname(&uts) == -1) {
   1290 		fprintf(stderr, "Unable to retrieve kernel version.\n");
   1291 		xtables_free_opts(1);
   1292 		exit(1);
   1293 	}
   1294 
   1295 	sscanf(uts.release, "%d.%d.%d", &x, &y, &z);
   1296 	kernel_version = LINUX_VERSION(x, y, z);
   1297 }
   1298 
   1299 static void command_jump(struct iptables_command_state *cs)
   1300 {
   1301 	size_t size;
   1302 
   1303 	set_option(&cs->options, OPT_JUMP, &cs->fw.ip.invflags, cs->invert);
   1304 	cs->jumpto = parse_target(optarg);
   1305 	/* TRY_LOAD (may be chain name) */
   1306 	cs->target = xtables_find_target(cs->jumpto, XTF_TRY_LOAD);
   1307 
   1308 	if (cs->target == NULL)
   1309 		return;
   1310 
   1311 	size = XT_ALIGN(sizeof(struct ipt_entry_target))
   1312 		+ cs->target->size;
   1313 
   1314 	cs->target->t = xtables_calloc(1, size);
   1315 	cs->target->t->u.target_size = size;
   1316 	strcpy(cs->target->t->u.user.name, cs->jumpto);
   1317 	cs->target->t->u.user.revision = cs->target->revision;
   1318 	if (cs->target->init != NULL)
   1319 		cs->target->init(cs->target->t);
   1320 	if (cs->target->x6_options != NULL)
   1321 		opts = xtables_options_xfrm(iptables_globals.orig_opts, opts,
   1322 					    cs->target->x6_options,
   1323 					    &cs->target->option_offset);
   1324 	else
   1325 		opts = xtables_merge_options(iptables_globals.orig_opts, opts,
   1326 					     cs->target->extra_opts,
   1327 					     &cs->target->option_offset);
   1328 	if (opts == NULL)
   1329 		xtables_error(OTHER_PROBLEM, "can't alloc memory!");
   1330 }
   1331 
   1332 static void command_match(struct iptables_command_state *cs)
   1333 {
   1334 	struct xtables_match *m;
   1335 	size_t size;
   1336 
   1337 	if (cs->invert)
   1338 		xtables_error(PARAMETER_PROBLEM,
   1339 			   "unexpected ! flag before --match");
   1340 
   1341 	m = xtables_find_match(optarg, XTF_LOAD_MUST_SUCCEED, &cs->matches);
   1342 	size = XT_ALIGN(sizeof(struct ipt_entry_match)) + m->size;
   1343 	m->m = xtables_calloc(1, size);
   1344 	m->m->u.match_size = size;
   1345 	strcpy(m->m->u.user.name, m->name);
   1346 	m->m->u.user.revision = m->revision;
   1347 	if (m->init != NULL)
   1348 		m->init(m->m);
   1349 	if (m == m->next)
   1350 		return;
   1351 	/* Merge options for non-cloned matches */
   1352 	if (m->x6_options != NULL)
   1353 		opts = xtables_options_xfrm(iptables_globals.orig_opts, opts,
   1354 					    m->x6_options, &m->option_offset);
   1355 	else if (m->extra_opts != NULL)
   1356 		opts = xtables_merge_options(iptables_globals.orig_opts, opts,
   1357 					     m->extra_opts, &m->option_offset);
   1358 	if (opts == NULL)
   1359 		xtables_error(OTHER_PROBLEM, "can't alloc memory!");
   1360 }
   1361 
   1362 int do_command4(int argc, char *argv[], char **table, struct iptc_handle **handle)
   1363 {
   1364 	struct iptables_command_state cs;
   1365 	struct ipt_entry *e = NULL;
   1366 	unsigned int nsaddrs = 0, ndaddrs = 0;
   1367 	struct in_addr *saddrs = NULL, *smasks = NULL;
   1368 	struct in_addr *daddrs = NULL, *dmasks = NULL;
   1369 
   1370 	int verbose = 0;
   1371 	const char *chain = NULL;
   1372 	const char *shostnetworkmask = NULL, *dhostnetworkmask = NULL;
   1373 	const char *policy = NULL, *newname = NULL;
   1374 	unsigned int rulenum = 0, command = 0;
   1375 	const char *pcnt = NULL, *bcnt = NULL;
   1376 	int ret = 1;
   1377 	struct xtables_match *m;
   1378 	struct xtables_rule_match *matchp;
   1379 	struct xtables_target *t;
   1380 	unsigned long long cnt;
   1381 
   1382 	memset(&cs, 0, sizeof(cs));
   1383 	cs.jumpto = "";
   1384 	cs.argv = argv;
   1385 
   1386 	/* re-set optind to 0 in case do_command4 gets called
   1387 	 * a second time */
   1388 	optind = 0;
   1389 
   1390 	/* clear mflags in case do_command4 gets called a second time
   1391 	 * (we clear the global list of all matches for security)*/
   1392 	for (m = xtables_matches; m; m = m->next)
   1393 		m->mflags = 0;
   1394 
   1395 	for (t = xtables_targets; t; t = t->next) {
   1396 		t->tflags = 0;
   1397 		t->used = 0;
   1398 	}
   1399 
   1400 	/* Suppress error messages: we may add new options if we
   1401            demand-load a protocol. */
   1402 	opterr = 0;
   1403 
   1404 	opts = xt_params->orig_opts;
   1405 	while ((cs.c = getopt_long(argc, argv,
   1406 	   "-:A:C:D:R:I:L::S::M:F::Z::N:X::E:P:Vh::o:p:s:d:j:i:fbvnt:m:xc:g:46",
   1407 					   opts, NULL)) != -1) {
   1408 		switch (cs.c) {
   1409 			/*
   1410 			 * Command selection
   1411 			 */
   1412 		case 'A':
   1413 			add_command(&command, CMD_APPEND, CMD_NONE,
   1414 				    cs.invert);
   1415 			chain = optarg;
   1416 			break;
   1417 
   1418 		case 'C':
   1419 			add_command(&command, CMD_CHECK, CMD_NONE,
   1420 				    cs.invert);
   1421 			chain = optarg;
   1422 			break;
   1423 
   1424 		case 'D':
   1425 			add_command(&command, CMD_DELETE, CMD_NONE,
   1426 				    cs.invert);
   1427 			chain = optarg;
   1428 			if (optind < argc && argv[optind][0] != '-'
   1429 			    && argv[optind][0] != '!') {
   1430 				rulenum = parse_rulenumber(argv[optind++]);
   1431 				command = CMD_DELETE_NUM;
   1432 			}
   1433 			break;
   1434 
   1435 		case 'R':
   1436 			add_command(&command, CMD_REPLACE, CMD_NONE,
   1437 				    cs.invert);
   1438 			chain = optarg;
   1439 			if (optind < argc && argv[optind][0] != '-'
   1440 			    && argv[optind][0] != '!')
   1441 				rulenum = parse_rulenumber(argv[optind++]);
   1442 			else
   1443 				xtables_error(PARAMETER_PROBLEM,
   1444 					   "-%c requires a rule number",
   1445 					   cmd2char(CMD_REPLACE));
   1446 			break;
   1447 
   1448 		case 'I':
   1449 			add_command(&command, CMD_INSERT, CMD_NONE,
   1450 				    cs.invert);
   1451 			chain = optarg;
   1452 			if (optind < argc && argv[optind][0] != '-'
   1453 			    && argv[optind][0] != '!')
   1454 				rulenum = parse_rulenumber(argv[optind++]);
   1455 			else rulenum = 1;
   1456 			break;
   1457 
   1458 		case 'L':
   1459 			add_command(&command, CMD_LIST,
   1460 				    CMD_ZERO | CMD_ZERO_NUM, cs.invert);
   1461 			if (optarg) chain = optarg;
   1462 			else if (optind < argc && argv[optind][0] != '-'
   1463 				 && argv[optind][0] != '!')
   1464 				chain = argv[optind++];
   1465 			if (optind < argc && argv[optind][0] != '-'
   1466 			    && argv[optind][0] != '!')
   1467 				rulenum = parse_rulenumber(argv[optind++]);
   1468 			break;
   1469 
   1470 		case 'S':
   1471 			add_command(&command, CMD_LIST_RULES,
   1472 				    CMD_ZERO|CMD_ZERO_NUM, cs.invert);
   1473 			if (optarg) chain = optarg;
   1474 			else if (optind < argc && argv[optind][0] != '-'
   1475 				 && argv[optind][0] != '!')
   1476 				chain = argv[optind++];
   1477 			if (optind < argc && argv[optind][0] != '-'
   1478 			    && argv[optind][0] != '!')
   1479 				rulenum = parse_rulenumber(argv[optind++]);
   1480 			break;
   1481 
   1482 		case 'F':
   1483 			add_command(&command, CMD_FLUSH, CMD_NONE,
   1484 				    cs.invert);
   1485 			if (optarg) chain = optarg;
   1486 			else if (optind < argc && argv[optind][0] != '-'
   1487 				 && argv[optind][0] != '!')
   1488 				chain = argv[optind++];
   1489 			break;
   1490 
   1491 		case 'Z':
   1492 			add_command(&command, CMD_ZERO, CMD_LIST|CMD_LIST_RULES,
   1493 				    cs.invert);
   1494 			if (optarg) chain = optarg;
   1495 			else if (optind < argc && argv[optind][0] != '-'
   1496 				&& argv[optind][0] != '!')
   1497 				chain = argv[optind++];
   1498 			if (optind < argc && argv[optind][0] != '-'
   1499 				&& argv[optind][0] != '!') {
   1500 				rulenum = parse_rulenumber(argv[optind++]);
   1501 				command = CMD_ZERO_NUM;
   1502 			}
   1503 			break;
   1504 
   1505 		case 'N':
   1506 			if (optarg && (*optarg == '-' || *optarg == '!'))
   1507 				xtables_error(PARAMETER_PROBLEM,
   1508 					   "chain name not allowed to start "
   1509 					   "with `%c'\n", *optarg);
   1510 			if (xtables_find_target(optarg, XTF_TRY_LOAD))
   1511 				xtables_error(PARAMETER_PROBLEM,
   1512 					   "chain name may not clash "
   1513 					   "with target name\n");
   1514 			add_command(&command, CMD_NEW_CHAIN, CMD_NONE,
   1515 				    cs.invert);
   1516 			chain = optarg;
   1517 			break;
   1518 
   1519 		case 'X':
   1520 			add_command(&command, CMD_DELETE_CHAIN, CMD_NONE,
   1521 				    cs.invert);
   1522 			if (optarg) chain = optarg;
   1523 			else if (optind < argc && argv[optind][0] != '-'
   1524 				 && argv[optind][0] != '!')
   1525 				chain = argv[optind++];
   1526 			break;
   1527 
   1528 		case 'E':
   1529 			add_command(&command, CMD_RENAME_CHAIN, CMD_NONE,
   1530 				    cs.invert);
   1531 			chain = optarg;
   1532 			if (optind < argc && argv[optind][0] != '-'
   1533 			    && argv[optind][0] != '!')
   1534 				newname = argv[optind++];
   1535 			else
   1536 				xtables_error(PARAMETER_PROBLEM,
   1537 					   "-%c requires old-chain-name and "
   1538 					   "new-chain-name",
   1539 					    cmd2char(CMD_RENAME_CHAIN));
   1540 			break;
   1541 
   1542 		case 'P':
   1543 			add_command(&command, CMD_SET_POLICY, CMD_NONE,
   1544 				    cs.invert);
   1545 			chain = optarg;
   1546 			if (optind < argc && argv[optind][0] != '-'
   1547 			    && argv[optind][0] != '!')
   1548 				policy = argv[optind++];
   1549 			else
   1550 				xtables_error(PARAMETER_PROBLEM,
   1551 					   "-%c requires a chain and a policy",
   1552 					   cmd2char(CMD_SET_POLICY));
   1553 			break;
   1554 
   1555 		case 'h':
   1556 			if (!optarg)
   1557 				optarg = argv[optind];
   1558 
   1559 			/* iptables -p icmp -h */
   1560 			if (!cs.matches && cs.protocol)
   1561 				xtables_find_match(cs.protocol,
   1562 					XTF_TRY_LOAD, &cs.matches);
   1563 
   1564 			exit_printhelp(cs.matches);
   1565 
   1566 			/*
   1567 			 * Option selection
   1568 			 */
   1569 		case 'p':
   1570 			xtables_check_inverse(optarg, &cs.invert, &optind, argc, argv);
   1571 			set_option(&cs.options, OPT_PROTOCOL, &cs.fw.ip.invflags,
   1572 				   cs.invert);
   1573 
   1574 			/* Canonicalize into lower case */
   1575 			for (cs.protocol = optarg; *cs.protocol; cs.protocol++)
   1576 				*cs.protocol = tolower(*cs.protocol);
   1577 
   1578 			cs.protocol = optarg;
   1579 			cs.fw.ip.proto = xtables_parse_protocol(cs.protocol);
   1580 
   1581 			if (cs.fw.ip.proto == 0
   1582 			    && (cs.fw.ip.invflags & IPT_INV_PROTO))
   1583 				xtables_error(PARAMETER_PROBLEM,
   1584 					   "rule would never match protocol");
   1585 			break;
   1586 
   1587 		case 's':
   1588 			xtables_check_inverse(optarg, &cs.invert, &optind, argc, argv);
   1589 			set_option(&cs.options, OPT_SOURCE, &cs.fw.ip.invflags,
   1590 				   cs.invert);
   1591 			shostnetworkmask = optarg;
   1592 			break;
   1593 
   1594 		case 'd':
   1595 			xtables_check_inverse(optarg, &cs.invert, &optind, argc, argv);
   1596 			set_option(&cs.options, OPT_DESTINATION, &cs.fw.ip.invflags,
   1597 				   cs.invert);
   1598 			dhostnetworkmask = optarg;
   1599 			break;
   1600 
   1601 #ifdef IPT_F_GOTO
   1602 		case 'g':
   1603 			set_option(&cs.options, OPT_JUMP, &cs.fw.ip.invflags,
   1604 				   cs.invert);
   1605 			cs.fw.ip.flags |= IPT_F_GOTO;
   1606 			cs.jumpto = parse_target(optarg);
   1607 			break;
   1608 #endif
   1609 
   1610 		case 'j':
   1611 			command_jump(&cs);
   1612 			break;
   1613 
   1614 
   1615 		case 'i':
   1616 			if (*optarg == '\0')
   1617 				xtables_error(PARAMETER_PROBLEM,
   1618 					"Empty interface is likely to be "
   1619 					"undesired");
   1620 			xtables_check_inverse(optarg, &cs.invert, &optind, argc, argv);
   1621 			set_option(&cs.options, OPT_VIANAMEIN, &cs.fw.ip.invflags,
   1622 				   cs.invert);
   1623 			xtables_parse_interface(optarg,
   1624 					cs.fw.ip.iniface,
   1625 					cs.fw.ip.iniface_mask);
   1626 			break;
   1627 
   1628 		case 'o':
   1629 			if (*optarg == '\0')
   1630 				xtables_error(PARAMETER_PROBLEM,
   1631 					"Empty interface is likely to be "
   1632 					"undesired");
   1633 			xtables_check_inverse(optarg, &cs.invert, &optind, argc, argv);
   1634 			set_option(&cs.options, OPT_VIANAMEOUT, &cs.fw.ip.invflags,
   1635 				   cs.invert);
   1636 			xtables_parse_interface(optarg,
   1637 					cs.fw.ip.outiface,
   1638 					cs.fw.ip.outiface_mask);
   1639 			break;
   1640 
   1641 		case 'f':
   1642 			set_option(&cs.options, OPT_FRAGMENT, &cs.fw.ip.invflags,
   1643 				   cs.invert);
   1644 			cs.fw.ip.flags |= IPT_F_FRAG;
   1645 			break;
   1646 
   1647 		case 'v':
   1648 			if (!verbose)
   1649 				set_option(&cs.options, OPT_VERBOSE,
   1650 					   &cs.fw.ip.invflags, cs.invert);
   1651 			verbose++;
   1652 			break;
   1653 
   1654 		case 'm':
   1655 			command_match(&cs);
   1656 			break;
   1657 
   1658 		case 'n':
   1659 			set_option(&cs.options, OPT_NUMERIC, &cs.fw.ip.invflags,
   1660 				   cs.invert);
   1661 			break;
   1662 
   1663 		case 't':
   1664 			if (cs.invert)
   1665 				xtables_error(PARAMETER_PROBLEM,
   1666 					   "unexpected ! flag before --table");
   1667 			*table = optarg;
   1668 			break;
   1669 
   1670 		case 'x':
   1671 			set_option(&cs.options, OPT_EXPANDED, &cs.fw.ip.invflags,
   1672 				   cs.invert);
   1673 			break;
   1674 
   1675 		case 'V':
   1676 			if (cs.invert)
   1677 				printf("Not %s ;-)\n", prog_vers);
   1678 			else
   1679 				printf("%s v%s\n",
   1680 				       prog_name, prog_vers);
   1681 			exit(0);
   1682 
   1683 		case '0':
   1684 			set_option(&cs.options, OPT_LINENUMBERS, &cs.fw.ip.invflags,
   1685 				   cs.invert);
   1686 			break;
   1687 
   1688 		case 'M':
   1689 			xtables_modprobe_program = optarg;
   1690 			break;
   1691 
   1692 		case 'c':
   1693 
   1694 			set_option(&cs.options, OPT_COUNTERS, &cs.fw.ip.invflags,
   1695 				   cs.invert);
   1696 			pcnt = optarg;
   1697 			bcnt = strchr(pcnt + 1, ',');
   1698 			if (bcnt)
   1699 			    bcnt++;
   1700 			if (!bcnt && optind < argc && argv[optind][0] != '-'
   1701 			    && argv[optind][0] != '!')
   1702 				bcnt = argv[optind++];
   1703 			if (!bcnt)
   1704 				xtables_error(PARAMETER_PROBLEM,
   1705 					"-%c requires packet and byte counter",
   1706 					opt2char(OPT_COUNTERS));
   1707 
   1708 			if (sscanf(pcnt, "%llu", &cnt) != 1)
   1709 				xtables_error(PARAMETER_PROBLEM,
   1710 					"-%c packet counter not numeric",
   1711 					opt2char(OPT_COUNTERS));
   1712 			cs.fw.counters.pcnt = cnt;
   1713 
   1714 			if (sscanf(bcnt, "%llu", &cnt) != 1)
   1715 				xtables_error(PARAMETER_PROBLEM,
   1716 					"-%c byte counter not numeric",
   1717 					opt2char(OPT_COUNTERS));
   1718 			cs.fw.counters.bcnt = cnt;
   1719 			break;
   1720 
   1721 		case '4':
   1722 			/* This is indeed the IPv4 iptables */
   1723 			break;
   1724 
   1725 		case '6':
   1726 			/* This is not the IPv6 ip6tables */
   1727 			if (line != -1)
   1728 				return 1; /* success: line ignored */
   1729 			fprintf(stderr, "This is the IPv4 version of iptables.\n");
   1730 			exit_tryhelp(2);
   1731 
   1732 		case 1: /* non option */
   1733 			if (optarg[0] == '!' && optarg[1] == '\0') {
   1734 				if (cs.invert)
   1735 					xtables_error(PARAMETER_PROBLEM,
   1736 						   "multiple consecutive ! not"
   1737 						   " allowed");
   1738 				cs.invert = TRUE;
   1739 				optarg[0] = '\0';
   1740 				continue;
   1741 			}
   1742 			fprintf(stderr, "Bad argument `%s'\n", optarg);
   1743 			exit_tryhelp(2);
   1744 
   1745 		default:
   1746 			if (command_default(&cs, &iptables_globals) == 1)
   1747 				/* cf. ip6tables.c */
   1748 				continue;
   1749 			break;
   1750 		}
   1751 		cs.invert = FALSE;
   1752 	}
   1753 
   1754 	if (strcmp(*table, "nat") == 0 &&
   1755 	    ((policy != NULL && strcmp(policy, "DROP") == 0) ||
   1756 	    (cs.jumpto != NULL && strcmp(cs.jumpto, "DROP") == 0)))
   1757 		xtables_error(PARAMETER_PROBLEM,
   1758 			"\nThe \"nat\" table is not intended for filtering, "
   1759 		        "the use of DROP is therefore inhibited.\n\n");
   1760 
   1761 	for (matchp = cs.matches; matchp; matchp = matchp->next)
   1762 		xtables_option_mfcall(matchp->match);
   1763 	if (cs.target != NULL)
   1764 		xtables_option_tfcall(cs.target);
   1765 
   1766 	/* Fix me: must put inverse options checking here --MN */
   1767 
   1768 	if (optind < argc)
   1769 		xtables_error(PARAMETER_PROBLEM,
   1770 			   "unknown arguments found on commandline");
   1771 	if (!command)
   1772 		xtables_error(PARAMETER_PROBLEM, "no command specified");
   1773 	if (cs.invert)
   1774 		xtables_error(PARAMETER_PROBLEM,
   1775 			   "nothing appropriate following !");
   1776 
   1777 	if (command & (CMD_REPLACE | CMD_INSERT | CMD_DELETE | CMD_APPEND | CMD_CHECK)) {
   1778 		if (!(cs.options & OPT_DESTINATION))
   1779 			dhostnetworkmask = "0.0.0.0/0";
   1780 		if (!(cs.options & OPT_SOURCE))
   1781 			shostnetworkmask = "0.0.0.0/0";
   1782 	}
   1783 
   1784 	if (shostnetworkmask)
   1785 		xtables_ipparse_multiple(shostnetworkmask, &saddrs,
   1786 					 &smasks, &nsaddrs);
   1787 
   1788 	if (dhostnetworkmask)
   1789 		xtables_ipparse_multiple(dhostnetworkmask, &daddrs,
   1790 					 &dmasks, &ndaddrs);
   1791 
   1792 	if ((nsaddrs > 1 || ndaddrs > 1) &&
   1793 	    (cs.fw.ip.invflags & (IPT_INV_SRCIP | IPT_INV_DSTIP)))
   1794 		xtables_error(PARAMETER_PROBLEM, "! not allowed with multiple"
   1795 			   " source or destination IP addresses");
   1796 
   1797 	if (command == CMD_REPLACE && (nsaddrs != 1 || ndaddrs != 1))
   1798 		xtables_error(PARAMETER_PROBLEM, "Replacement rule does not "
   1799 			   "specify a unique address");
   1800 
   1801 	generic_opt_check(command, cs.options);
   1802 
   1803 	if (chain != NULL && strlen(chain) >= XT_EXTENSION_MAXNAMELEN)
   1804 		xtables_error(PARAMETER_PROBLEM,
   1805 			   "chain name `%s' too long (must be under %u chars)",
   1806 			   chain, XT_EXTENSION_MAXNAMELEN);
   1807 
   1808 	/* only allocate handle if we weren't called with a handle */
   1809 	if (!*handle)
   1810 		*handle = iptc_init(*table);
   1811 
   1812 	/* try to insmod the module if iptc_init failed */
   1813 	if (!*handle && xtables_load_ko(xtables_modprobe_program, false) != -1)
   1814 		*handle = iptc_init(*table);
   1815 
   1816 	if (!*handle)
   1817 		xtables_error(VERSION_PROBLEM,
   1818 			   "can't initialize iptables table `%s': %s",
   1819 			   *table, iptc_strerror(errno));
   1820 
   1821 	if (command == CMD_APPEND
   1822 	    || command == CMD_DELETE
   1823 	    || command == CMD_CHECK
   1824 	    || command == CMD_INSERT
   1825 	    || command == CMD_REPLACE) {
   1826 		if (strcmp(chain, "PREROUTING") == 0
   1827 		    || strcmp(chain, "INPUT") == 0) {
   1828 			/* -o not valid with incoming packets. */
   1829 			if (cs.options & OPT_VIANAMEOUT)
   1830 				xtables_error(PARAMETER_PROBLEM,
   1831 					   "Can't use -%c with %s\n",
   1832 					   opt2char(OPT_VIANAMEOUT),
   1833 					   chain);
   1834 		}
   1835 
   1836 		if (strcmp(chain, "POSTROUTING") == 0
   1837 		    || strcmp(chain, "OUTPUT") == 0) {
   1838 			/* -i not valid with outgoing packets */
   1839 			if (cs.options & OPT_VIANAMEIN)
   1840 				xtables_error(PARAMETER_PROBLEM,
   1841 					   "Can't use -%c with %s\n",
   1842 					   opt2char(OPT_VIANAMEIN),
   1843 					   chain);
   1844 		}
   1845 
   1846 		if (cs.target && iptc_is_chain(cs.jumpto, *handle)) {
   1847 			fprintf(stderr,
   1848 				"Warning: using chain %s, not extension\n",
   1849 				cs.jumpto);
   1850 
   1851 			if (cs.target->t)
   1852 				free(cs.target->t);
   1853 
   1854 			cs.target = NULL;
   1855 		}
   1856 
   1857 		/* If they didn't specify a target, or it's a chain
   1858 		   name, use standard. */
   1859 		if (!cs.target
   1860 		    && (strlen(cs.jumpto) == 0
   1861 			|| iptc_is_chain(cs.jumpto, *handle))) {
   1862 			size_t size;
   1863 
   1864 			cs.target = xtables_find_target(IPT_STANDARD_TARGET,
   1865 					 XTF_LOAD_MUST_SUCCEED);
   1866 
   1867 			size = sizeof(struct ipt_entry_target)
   1868 				+ cs.target->size;
   1869 			cs.target->t = xtables_calloc(1, size);
   1870 			cs.target->t->u.target_size = size;
   1871 			strcpy(cs.target->t->u.user.name, cs.jumpto);
   1872 			if (!iptc_is_chain(cs.jumpto, *handle))
   1873 				cs.target->t->u.user.revision = cs.target->revision;
   1874 			if (cs.target->init != NULL)
   1875 				cs.target->init(cs.target->t);
   1876 		}
   1877 
   1878 		if (!cs.target) {
   1879 			/* it is no chain, and we can't load a plugin.
   1880 			 * We cannot know if the plugin is corrupt, non
   1881 			 * existant OR if the user just misspelled a
   1882 			 * chain. */
   1883 #ifdef IPT_F_GOTO
   1884 			if (cs.fw.ip.flags & IPT_F_GOTO)
   1885 				xtables_error(PARAMETER_PROBLEM,
   1886 					   "goto '%s' is not a chain\n",
   1887 					   cs.jumpto);
   1888 #endif
   1889 			xtables_find_target(cs.jumpto, XTF_LOAD_MUST_SUCCEED);
   1890 		} else {
   1891 			e = generate_entry(&cs.fw, cs.matches, cs.target->t);
   1892 			free(cs.target->t);
   1893 		}
   1894 	}
   1895 
   1896 	switch (command) {
   1897 	case CMD_APPEND:
   1898 		ret = append_entry(chain, e,
   1899 				   nsaddrs, saddrs, smasks,
   1900 				   ndaddrs, daddrs, dmasks,
   1901 				   cs.options&OPT_VERBOSE,
   1902 				   *handle);
   1903 		break;
   1904 	case CMD_DELETE:
   1905 		ret = delete_entry(chain, e,
   1906 				   nsaddrs, saddrs, smasks,
   1907 				   ndaddrs, daddrs, dmasks,
   1908 				   cs.options&OPT_VERBOSE,
   1909 				   *handle, cs.matches, cs.target);
   1910 		break;
   1911 	case CMD_DELETE_NUM:
   1912 		ret = iptc_delete_num_entry(chain, rulenum - 1, *handle);
   1913 		break;
   1914 	case CMD_CHECK:
   1915 		ret = check_entry(chain, e,
   1916 				   nsaddrs, saddrs, smasks,
   1917 				   ndaddrs, daddrs, dmasks,
   1918 				   cs.options&OPT_VERBOSE,
   1919 				   *handle, cs.matches, cs.target);
   1920 		break;
   1921 	case CMD_REPLACE:
   1922 		ret = replace_entry(chain, e, rulenum - 1,
   1923 				    saddrs, smasks, daddrs, dmasks,
   1924 				    cs.options&OPT_VERBOSE, *handle);
   1925 		break;
   1926 	case CMD_INSERT:
   1927 		ret = insert_entry(chain, e, rulenum - 1,
   1928 				   nsaddrs, saddrs, smasks,
   1929 				   ndaddrs, daddrs, dmasks,
   1930 				   cs.options&OPT_VERBOSE,
   1931 				   *handle);
   1932 		break;
   1933 	case CMD_FLUSH:
   1934 		ret = flush_entries4(chain, cs.options&OPT_VERBOSE, *handle);
   1935 		break;
   1936 	case CMD_ZERO:
   1937 		ret = zero_entries(chain, cs.options&OPT_VERBOSE, *handle);
   1938 		break;
   1939 	case CMD_ZERO_NUM:
   1940 		ret = iptc_zero_counter(chain, rulenum, *handle);
   1941 		break;
   1942 	case CMD_LIST:
   1943 	case CMD_LIST|CMD_ZERO:
   1944 	case CMD_LIST|CMD_ZERO_NUM:
   1945 		ret = list_entries(chain,
   1946 				   rulenum,
   1947 				   cs.options&OPT_VERBOSE,
   1948 				   cs.options&OPT_NUMERIC,
   1949 				   cs.options&OPT_EXPANDED,
   1950 				   cs.options&OPT_LINENUMBERS,
   1951 				   *handle);
   1952 		if (ret && (command & CMD_ZERO))
   1953 			ret = zero_entries(chain,
   1954 					   cs.options&OPT_VERBOSE, *handle);
   1955 		if (ret && (command & CMD_ZERO_NUM))
   1956 			ret = iptc_zero_counter(chain, rulenum, *handle);
   1957 		break;
   1958 	case CMD_LIST_RULES:
   1959 	case CMD_LIST_RULES|CMD_ZERO:
   1960 	case CMD_LIST_RULES|CMD_ZERO_NUM:
   1961 		ret = list_rules(chain,
   1962 				   rulenum,
   1963 				   cs.options&OPT_VERBOSE,
   1964 				   *handle);
   1965 		if (ret && (command & CMD_ZERO))
   1966 			ret = zero_entries(chain,
   1967 					   cs.options&OPT_VERBOSE, *handle);
   1968 		if (ret && (command & CMD_ZERO_NUM))
   1969 			ret = iptc_zero_counter(chain, rulenum, *handle);
   1970 		break;
   1971 	case CMD_NEW_CHAIN:
   1972 		ret = iptc_create_chain(chain, *handle);
   1973 		break;
   1974 	case CMD_DELETE_CHAIN:
   1975 		ret = delete_chain4(chain, cs.options&OPT_VERBOSE, *handle);
   1976 		break;
   1977 	case CMD_RENAME_CHAIN:
   1978 		ret = iptc_rename_chain(chain, newname,	*handle);
   1979 		break;
   1980 	case CMD_SET_POLICY:
   1981 		ret = iptc_set_policy(chain, policy, cs.options&OPT_COUNTERS ? &cs.fw.counters : NULL, *handle);
   1982 		break;
   1983 	default:
   1984 		/* We should never reach this... */
   1985 		exit_tryhelp(2);
   1986 	}
   1987 
   1988 	if (verbose > 1)
   1989 		dump_entries(*handle);
   1990 
   1991 	clear_rule_matches(&cs.matches);
   1992 
   1993 	if (e != NULL) {
   1994 		free(e);
   1995 		e = NULL;
   1996 	}
   1997 
   1998 	free(saddrs);
   1999 	free(smasks);
   2000 	free(daddrs);
   2001 	free(dmasks);
   2002 	xtables_free_opts(1);
   2003 
   2004 	return ret;
   2005 }
   2006