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/*
 * Author: Paul.Russell@rustcorp.com.au
 *
 * Based on the ipfwadm code by Jos Vos <jos@xos.nl> (see README).
 *
 *	ipchains -- IP firewall administration for kernels with
 * CONFIG_IP_FIREWALL_CHAINS.
 *
 *	See the accompanying manual page ipchains(8) for information
 *	about proper usage of this program.
 *
 *	This program is free software; you can redistribute it and/or modify
 *	it under the terms of the GNU General Public License as published by
 *	the Free Software Foundation; either version 2 of the License, or
 *	(at your option) any later version.
 *
 *	This program is distributed in the hope that it will be useful,
 *	but WITHOUT ANY WARRANTY; without even the implied warranty of
 *	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *	GNU General Public License for more details.
 *
 *	You should have received a copy of the GNU General Public License
 *	along with this program; if not, write to the Free Software
 *	Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 *
 * History:
 * 1.0: First release
 * 1.0.1: Generic protocols allowed (matching ip_fwtrees.h changes).
 *        Tighter TOS checking (replaced silent kernel TOS mangling).
 *        RETURN target allowed (matching ip_fwtrees.c changes).
 *        Bug fix for port handling (port ranges broken?).
 *        Bug fix for possible bad return values from delete_entry and
 *         append_entry.
 * 1.0.2: User & marking support.  Removed -a option (interface address).
 * 1.1:   Inverse rule support.
 *        Removal of -k option (ACK).
 *        Moved -b option to userspace (BIDIR).
 *        Removed multiple port support.
 *        Fixed bug in handling of > 8 rules.
 * 1.1.1: Added ICMP code support.
 *        Extra check for multiple DNS resolutions and ! or -b.
 *        Fixed -b code (now swaps address masks as well).
 *        Handle EINVAL from IP_FW_DELETE command.
 * 1.2:   Added wildcard interface support.
 * 1.2.1: Fixed parsing of inverse interfaces (broken in 1.2).
 * 1.2.2: Allow /proc/net/ip_fwnames to contain policy names (so same
 *        across 2.0/2.1 kernels).
 * 1.3:   Added `-o' option for netlink support.
 *        Enumerated exit types.
 *        Added output for delete in verbose mode.
 *        Added -X with no chain name to delete all chains.
 *        Added support for policy counters (kernel change).
 *        Removed old-style (numeric) policy handling.
 *        Fixed masquerade typo so masq works again.
 *        Handle ICMP masq.
 * 1.3.1: Move headers out to kernel_headers for glibc compatibility.
 *        Policies now handed to kernel in string form (kernel change).
 * 1.3.2: Handle generic masq. protocols.
 *        Fixed -S option.
 * 1.3.3: Marks now printed in hex.
 *        kernel_headers.h now works with libc5 again.
 *        Set IP_FW_F_WILDIF for zero-length interface names.
 * 1.3.4: Fixed handling of REDIRECT without a port number.
 *        Handles "" wildcard interfaces from kernel correctly.
 * 1.3.5: Fixed masq time calcs for HZ != 100.
 *        Improved invalid flags error messages.
 * 1.3.6: Split into separate kernel-interface library libipfwc.
 *        Don't give MAILME error for invalid rule numbers.
 * 1.3.7: Andi Kleen additions: long options.
 *        & read /etc/protocols for protocols.
 *        Fixed spelling of `CMD_MASQERADE' and `CMD_SET_MASQERADE'.
 *        Cleaned up -h output.
 *        Fixed -Z option (zero, not flush!).
 *        Fixed wrong list_masq return value.
 *        Fixed libipfwc bug with ipfwc_check_packet().
 * 1.3.8: -L now works for listing chains other than input.
 *        [ Thanks to Bernhard Weisshuhn ].
 */

#include <stdio.h>
#include <stdarg.h>
#include <errno.h>
#include <limits.h>
#include <string.h>
#include <stdlib.h>
#include <unistd.h>
#include <ctype.h>
#include <getopt.h>
#include <netdb.h>
#include <sys/param.h>
#include <pwd.h>
#include <sys/types.h>

#include "include/libipfwc.h"

#ifndef TRUE
#define TRUE 1
#endif
#ifndef FALSE
#define FALSE 0
#endif

#ifndef	IP_FW_F_REDIR
#define IPFWADM_NO_REDIR
#define IP_FW_F_REDIR		0
#endif	/* ! IP_FW_F_REDIR */

#ifndef	IP_FW_MASQ_TIMEOUTS
#define IPFWADM_NO_TIMEOUT
#define IP_FW_MASQ_TIMEOUTS	0
#endif	/* ! IP_FW_MASQ_TIMEOUTS */

#define CHN_NONE	-1
#define CHN_FWD		0
#define CHN_IN		1
#define CHN_OUT		2
#define CHN_MASQ	3	/* only used for listing masquerading */

#define CMD_NONE		0x0000U
#define CMD_INSERT		0x0001U
#define CMD_DELETE		0x0002U
#define CMD_DELETE_NUM		0x0004U
#define CMD_REPLACE		0x0008U
#define CMD_APPEND		0x0010U
#define CMD_LIST		0x0020U
#define CMD_FLUSH		0x0040U
#define CMD_ZERO		0x0080U
#define CMD_NEW_CHAIN		0x0100u
#define CMD_DELETE_CHAIN	0x0200U
#define CMD_SET_POLICY		0x0400U
#define CMD_MASQUERADE		0x0800U
#define CMD_SET_MASQUERADE	0x1000U
#define CMD_CHECK		0x2000U
#define NUMBER_OF_CMD	14
static const char cmdflags[] = { 'I', 'D', 'D', 'R', 'A', 'L', 'F', 'Z',
				 'N', 'X', 'P', 'M', 'S', 'C' };

#define OPT_NONE	0x00000U
#define OPT_NUMERIC	0x00001U
#define OPT_SOURCE	0x00002U
#define OPT_DESTINATION	0x00004U
#define OPT_PROTOCOL	0x00008U
#define OPT_JUMP	0x00010U
#define OPT_TCPSYN	0x00020U
#define OPT_BIDIR	0x00040U
#define OPT_VERBOSE	0x00080U
#define OPT_PRINTK	0x00100U
#define OPT_EXPANDED	0x00200U
#define OPT_TOS		0x00400U
#define OPT_VIANAME	0x00800U
#define OPT_FRAGMENT    0x01000U
#define OPT_MARK        0x02000U
#define OPT_SRCPT       0x04000U
#define OPT_DSTPT       0x08000U
#define OPT_NETLINK     0x10000U
#define NUMBER_OF_OPT	17
static const char optflags[] = { 'n', 's', 'd', 'p', 'j', 'y', 'b', 'v',
				 'l', 'x', 't', 'i', 'f', 'm', 's', 'd', 'o'};

#define FMT_NUMERIC	0x0001
#define FMT_NOCOUNTS	0x0002
#define FMT_KILOMEGAGIGA 0x0004
#define FMT_OPTIONS	0x0008
#define FMT_NOTABLE	0x0010
#define FMT_HEADER	0x0020
#define FMT_NOTARGET	0x0040
#define FMT_VIA		0x0080
#define FMT_NONEWLINE	0x0100
#define FMT_DELTAS	0x0200
#define FMT_TOS		0x0400
#define FMT_MARK        0x0800
#define FMT_NETLINK     0x1000

#define FMT_PRINT_RULE (FMT_NOCOUNTS | FMT_OPTIONS | FMT_TOS | FMT_VIA \
			| FMT_NUMERIC | FMT_NOTABLE | FMT_MARK | FMT_NETLINK)

struct option opts[] = {
	{ "append", 1, 0, 'A' },
	{ "delete", 1, 0,  'D' },
	{ "insert", 1, 0,  'I' },
	{ "replace", 1, 0,  'R' },
	{ "list", 2, 0,  'L' },
	{ "flush", 2, 0,  'F' },
	{ "zero", 2, 0,  'Z' },
	{ "check", 1, 0,  'C' },
	{ "new-chain", 1, 0,  'N' },
	{ "delete-chain", 1, 0,  'X' },
	{ "policy", 1, 0,  'P' },
	{ "masquerading", 0, 0,  'M' },
	{ "set", 1, 0,  'S' },
	{ "bidirectional", 0, 0,  'b' },
	{ "source", 1, 0, 's' },
	{ "destination", 1, 0,  'd' },
	{ "src", 1, 0,  's' }, /* synonym */
	{ "dst", 1, 0,  'd' }, /* synonym */
	{ "source-port", 1, 0, '1' },
	{ "destination-port", 1, 0, '2' },
	{ "icmp-type", 1, 0, '1' },
	{ "sport", 1, 0, '1' }, /* synonym */
	{ "dport", 1, 0, '2' }, /* synonym */
	{ "proto", 1, 0,  'p' },
	{ "interface", 1, 0, 'i' },
	{ "jump", 1, 0, 'j' },
	{ "TOS", 1, 0, 't' },
	{ "mark", 1, 0, 'm' },
	{ "numeric", 0, 0, 'n' },
	{ "log", 0, 0, 'l' },
	{ "output", 2, 0, 'o' },
	{ "verbose", 0, 0, 'v' },
	{ "exact", 0, 0, 'x' },
	{ "fragments", 0, 0, 'f' },
	{ "syn", 0, 0, 'y' },
	{ "version", 0, 0, 'V' },
	{ "help", 0, 0, 'h'},
	{0}
};

/* TOS names and values. */
struct TOS_value
{
	unsigned char TOS;
	const char *name;
} TOS_values[] = {
#ifdef NOT_A_GODDAMN_YANK
	{ 0x10, "Minimise Delay" },
	{ 0x08, "Minimise Throughput" },
	{ 0x04, "Maximise Reliability" },
	{ 0x01, "Minimise Cost" },
#else
	{ 0x10, "Minimize Delay" },
	{ 0x08, "Minimize Throughput" },
	{ 0x04, "Maximize Reliability" },
	{ 0x01, "Minimize Cost" },
#endif
	{ 0x00, "Normal Service" },
};

/* Table of legal combinations of commands and options.  If any of the
 * given commands make an option legal, that option is legal (applies to
 * CMD_LIST and CMD_ZERO only).
 * Key:
 *  +  compulsory
 *  x  illegal
 *     optional
 */

static char commands_v_options[NUMBER_OF_CMD][NUMBER_OF_OPT] =
/* Well, it's better than "Re: Linux vs FreeBSD" */
{
	/*     -n  -s  -d  -p  -j  -y  -b  -v  -l  -x  -t  -i  -f  -m  -s  -d  -o */
/*INSERT*/    {'x',' ',' ',' ',' ',' ',' ',' ',' ','x',' ',' ',' ',' ',' ',' ',' '},
/*DELETE*/    {'x',' ',' ',' ',' ',' ',' ',' ',' ','x',' ',' ',' ',' ',' ',' ',' '},
/*DELETE_NUM*/{'x','x','x','x','x','x','x',' ','x','x','x','x','x','x','x','x','x'},
/*REPLACE*/   {'x',' ',' ',' ',' ',' ','x',' ',' ','x',' ',' ',' ',' ',' ',' ',' '},
/*APPEND*/    {'x',' ',' ',' ',' ',' ',' ',' ',' ','x',' ',' ',' ',' ',' ',' ',' '},
/*LIST*/      {' ','x','x','x','x','x','x',' ','x',' ','x','x','x','x','x','x','x'},
/*FLUSH*/     {'x','x','x','x','x','x','x',' ','x','x','x','x','x','x','x','x','x'},
/*ZERO*/      {'x','x','x','x','x','x','x',' ','x','x','x','x','x','x','x','x','x'},
/*NEW_CHAIN*/ {'x','x','x','x','x','x','x',' ','x','x','x','x','x','x','x','x','x'},
/*DEL_CHAIN*/ {'x','x','x','x','x','x','x',' ','x','x','x','x','x','x','x','x','x'},
/*SET_POLICY*/{'x','x','x','x','x','x','x',' ','x','x','x','x','x','x','x','x','x'},
/*MASQUERADE*/{'x','x','x','x','x','x','x','x','x','x','x','x','x','x','x','x','x'},
/*SET_MASQ*/  {'x','x','x','x','x','x','x',' ','x','x','x','x','x','x','x','x','x'},
/*CHECK*/     {'x','+','+','+','x',' ',' ',' ','x','x','x','+',' ','x',' ',' ','x'}
};

static int inverse_for_options[NUMBER_OF_OPT] =
{
/* -n */ 0,
/* -s */ IP_FW_INV_SRCIP,
/* -d */ IP_FW_INV_DSTIP,
/* -p */ IP_FW_INV_PROTO,
/* -j */ 0,
/* -y */ IP_FW_INV_SYN,
/* -b */ 0,
/* -v */ 0,
/* -l */ 0,
/* -x */ 0,
/* -t */ 0,
/* -i */ IP_FW_INV_VIA,
/* -f */ IP_FW_INV_FRAG,
/* -m */ 0,
/* -s */ IP_FW_INV_SRCPT,
/* -d */ IP_FW_INV_DSTPT,
/* -o */ 0
};

struct masq {
	unsigned long	expires;	/* Expiration timer */
	char proto[20];		/* Which protocol are we talking? */
	struct in_addr	src, dst;	/* Source and destination IP addresses */
	unsigned short	sport, dport;	/* Source and destination ports */
	unsigned short	mport;		/* Masqueraded port */
	__u32		initseq;	/* Add delta from this seq. on */
	short		delta;		/* Delta in sequence numbers */
	short		pdelta;		/* Delta in sequence numbers before last */
};

struct masq_timeout {
	int	tcp_timeout;
	int	tcp_fin_timeout;
	int	udp_timeout;
} timeouts;

static char package_version[] = "ipchains 1.3.8, 27-Oct-1998";

static const char *program;

/* Do we invert the next option? */
static int invert = FALSE;

static int check_inverse(const char option[], int *invert);

/* Parsing functions for command line. */
static struct in_addr *parse_hostnetwork(const char *, unsigned int *);
static void parse_hostnetworkmask(const char *, struct in_addr **,
	struct in_addr *, unsigned int *);
static struct in_addr *parse_mask(char *);
static unsigned short int parse_protocol(const char *);
static const char * parse_policy(const char *chain, const char *policy);
static void parse_icmp(const char *srcportstring, const char *dstportstring,
		       __u16 *type, __u16* code, int *options, __u16 invflags,
		       int checking);
static void parse_ports(const char *portstring, __u16 *ports, __u16 proto);
static __u16 parse_port(const char *port, unsigned short proto);
static unsigned short parse_mark(char *markstring, __u32 *mark);
static unsigned short parse_outputsize(char *outputstring, __u16 *outputsize);
static unsigned short parse_interface(const char *ifstring, char *vianame);
static void parse_hexbyte(char *, unsigned char *);
static int parse_timeout(char *);
static const char *parse_target(const char *targetname);
static int parse_rulenumber(const char *rule);

/* Various parsing helper functions */
static struct in_addr *host_to_addr(const char *, unsigned int *);
static char *addr_to_host(struct in_addr *);
static struct in_addr *network_to_addr(const char *);
static char *addr_to_network(struct in_addr *);
static char *addr_to_anyname(struct in_addr *);
static struct in_addr *dotted_to_addr(const char *);
static char *addr_to_dotted(struct in_addr *);
static char *mask_to_dotted(struct in_addr *);
static int service_to_port(const char *, unsigned short);
static char *port_to_service(int, unsigned short);
static int string_to_number(const char *, int, int);

/* Check the options based on the tables above */
static void generic_opt_check(int command, int options);
static char opt2char(int option);
static char cmd2char(int option);
static void add_command(int *cmd, const int newcmd, const int othercmds);

/* Check for illegal TOS manipulation */
static void check_tos(unsigned char tosand, unsigned char tosxor);

static int list_masq(unsigned int options);

static void print_firewall(FILE *, struct ip_fwuser *, __u64, __u64, int);
static void print_masq(FILE *, struct masq *, int);
static int read_masqinfo(FILE *, struct masq *, int);

static void set_option(unsigned int *options,
		       unsigned int option,
		       __u16 *invflg);
static void inaddrcpy(struct in_addr *, struct in_addr *);
static void *fw_malloc(size_t);
static void *fw_calloc(size_t, size_t);
static void *fw_realloc(void *, size_t);
enum exittype {
	OTHER_PROBLEM = 1,
	PARAMETER_PROBLEM,
	VERSION_PROBLEM
};
static void exit_error(enum exittype, char *, ...)
  __attribute__((noreturn, format(printf,2,3)));
static void exit_tryhelp(int) __attribute__((noreturn));
static void exit_printicmphelp() __attribute__((noreturn));
static void exit_printhelp() __attribute__((noreturn));


struct icmp_names {
	const char *name;
	__u16 type;
	__u16 code_min, code_max;
	int use_code_min_for_testing;
};

const struct icmp_names icmp_codes[] = {
	{ "echo-reply", 0, 0, 0xFFFF, TRUE },
	/* Alias */ { "pong", 0, 0, 0xFFFF, TRUE },

	{ "destination-unreachable", 3, 0, 0xFFFF, FALSE },
	{   "network-unreachable", 3, 0, 0, TRUE },
	{   "host-unreachable", 3, 1, 1, TRUE },
	{   "protocol-unreachable", 3, 2, 2, TRUE },
	{   "port-unreachable", 3, 3, 3, TRUE },
	{   "fragmentation-needed", 3, 4, 4, TRUE },
	{   "source-route-failed", 3, 5, 5, TRUE },
	{   "network-unknown", 3, 6, 6, TRUE },
	{   "host-unknown", 3, 7, 7, TRUE },
	{   "network-prohibited", 3, 9, 9, TRUE },
	{   "host-prohibited", 3, 10, 10, TRUE },
	{   "TOS-network-unreachable", 3, 11, 11, TRUE },
	{   "TOS-host-unreachable", 3, 12, 12, TRUE },
	{   "communication-prohibited", 3, 13, 13, TRUE },
	{   "host-precedence-violation", 3, 14, 14, TRUE },
	{   "precedence-cutoff", 3, 15, 15, TRUE },

	{ "source-quench", 4, 0, 0xFFFF, TRUE },

	{ "redirect", 5, 0, 0xFFFF, FALSE },
	{   "network-redirect", 5, 0, 0, TRUE },
	{   "host-redirect", 5, 1, 1, TRUE },
	{   "TOS-network-redirect", 5, 2, 2, TRUE },
	{   "TOS-host-redirect", 5, 3, 3, TRUE },

	{ "echo-request", 8, 0, 0xFFFF, TRUE },
	/* Alias */ { "ping", 8, 0, 0xFFFF, TRUE },

	{ "router-advertisement", 9, 0, 0xFFFF, TRUE },

	{ "router-solicitation", 10, 0, 0xFFFF, TRUE },

	{ "time-exceeded", 11, 0, 0xFFFF, FALSE },
	/* Alias */ { "ttl-exceeded", 11, 0, 0xFFFF, FALSE },
	{   "ttl-zero-during-transit", 11, 0, 0, TRUE },
	{   "ttl-zero-during-reassembly", 11, 1, 1, TRUE },

	{ "parameter-problem", 12, 0, 0xFFFF, FALSE },
	{   "ip-header-bad", 12, 0, 0, TRUE },
	{   "required-option-missing", 12, 1, 1, TRUE },

	{ "timestamp-request", 13, 0, 0xFFFF, TRUE },

	{ "timestamp-reply", 14, 0, 0xFFFF, TRUE },

	{ "address-mask-request", 17, 0, 0xFFFF, TRUE },

	{ "address-mask-reply", 18, 0, 0xFFFF, TRUE }
};

static void
swap_info(struct ip_fw *fw, int isicmp)
{
	__u16 tmp;
	__u32 tmpMask;

	/* Swap source and dest masks. */
	tmpMask = fw->fw_smsk.s_addr;
	fw->fw_smsk.s_addr = fw->fw_dmsk.s_addr;
	fw->fw_dmsk.s_addr = tmpMask;

	/* Swap source an dest inverse flags (clear and reset)*/
	tmp = fw->fw_invflg;
	fw->fw_invflg &= ~(IP_FW_INV_SRCIP | IP_FW_INV_DSTIP);
	fw->fw_invflg |= ((tmp & IP_FW_INV_SRCIP ? IP_FW_INV_DSTIP : 0)
			  | (tmp & IP_FW_INV_DSTIP ? IP_FW_INV_SRCIP : 0));

	if (!isicmp) {
		/* Swap source & dest ports */
		tmp = fw->fw_spts[0];
		fw->fw_spts[0] = fw->fw_dpts[0];
		fw->fw_dpts[0] = tmp;

		tmp = fw->fw_spts[1];
		fw->fw_spts[1] = fw->fw_dpts[1];
		fw->fw_dpts[1] = tmp;

		/* Swap src & dst port inverse flags.*/
		tmp = fw->fw_invflg;
		fw->fw_invflg &= ~(IP_FW_INV_SRCPT | IP_FW_INV_DSTPT);

		fw->fw_invflg |= ((tmp & IP_FW_INV_SRCPT ? IP_FW_INV_DSTPT : 0)
				  | (tmp & IP_FW_INV_DSTPT ? IP_FW_INV_SRCPT : 0));
	}
}

static int
append_entry(const ip_chainlabel chain,
	     const struct ip_fwuser *fw,
	     unsigned int nsaddrs,
	     const struct in_addr saddrs[],
	     unsigned int ndaddrs,
	     const struct in_addr daddrs[],
	     int verbose,
	     int bidir)
{
	unsigned int i, j;
	struct ip_fwuser ipfw = *fw;
	int ret = 1;

	for (i = 0; i < nsaddrs; i++) {
		ipfw.ipfw.fw_src.s_addr = saddrs[i].s_addr;
		for (j = 0; j < ndaddrs; j++) {
			ipfw.ipfw.fw_dst.s_addr = daddrs[j].s_addr;
			if (verbose)
				print_firewall(stdout, &ipfw,
					       0, 0, FMT_PRINT_RULE);
			ret &= ipfwc_append_entry(chain, &ipfw);
		}
	}

	if (bidir) {
		swap_info(&ipfw.ipfw, ipfw.ipfw.fw_proto == IPPROTO_ICMP);
		ret &= append_entry(chain, &ipfw, ndaddrs, daddrs,
				    nsaddrs, saddrs, verbose, 0);
	}
	return ret;
}

static int
replace_entry(const ip_chainlabel chain,
	      const struct ip_fwuser *fw,
	      unsigned int rulenum,
	      const struct in_addr *saddr,
	      const struct in_addr *daddr,
	      int verbose)
{
	struct ip_fwuser ipfw = *fw;
	ipfw.ipfw.fw_src.s_addr = saddr->s_addr;
	ipfw.ipfw.fw_dst.s_addr = daddr->s_addr;

	if (verbose)
		print_firewall(stdout, &ipfw, 0, 0, FMT_PRINT_RULE);
	return ipfwc_replace_entry(chain, &ipfw, rulenum);
}

static int
insert_entry(const ip_chainlabel chain,
	     const struct ip_fwuser *fw,
	     unsigned int rulenum,
	     unsigned int nsaddrs,
	     const struct in_addr saddrs[],
	     unsigned int ndaddrs,
	     const struct in_addr daddrs[],
	     int verbose, int bidir)
{
	unsigned int i, j;
	int ret = 1;
	struct ip_fwuser ipfw = *fw;

	for (i = 0; i < nsaddrs; i++) {
		ipfw.ipfw.fw_src.s_addr = saddrs[i].s_addr;
		for (j = 0; j < ndaddrs; j++) {
			ipfw.ipfw.fw_dst.s_addr = daddrs[j].s_addr;
			if (verbose)
				print_firewall(stdout, &ipfw,
					       0, 0, FMT_PRINT_RULE);
			ret &= ipfwc_insert_entry(chain, &ipfw, rulenum);
		}
	}
	if (bidir) {
		swap_info(&ipfw.ipfw, ipfw.ipfw.fw_proto == IPPROTO_ICMP);
		ret &= insert_entry(chain, &ipfw, rulenum, ndaddrs, daddrs,
				    nsaddrs, saddrs, verbose, 0);
	}

	return ret;
}

static int
delete_entry(const ip_chainlabel chain,
	     const struct ip_fwuser *fw,
	     unsigned int nsaddrs,
	     const struct in_addr saddrs[],
	     unsigned int ndaddrs,
	     const struct in_addr daddrs[],
	     int verbose, int bidir)
{
	unsigned int i, j;
	struct ip_fwuser ipfw = *fw;
	int ret = 1;

	for (i = 0; i < nsaddrs; i++) {
		ipfw.ipfw.fw_src.s_addr = saddrs[i].s_addr;
		for (j = 0; j < ndaddrs; j++) {
			ipfw.ipfw.fw_dst.s_addr = daddrs[j].s_addr;
			if (verbose)
				print_firewall(stdout, &ipfw,
					       0, 0, FMT_PRINT_RULE);
			ret &= ipfwc_delete_entry(chain, &ipfw);
		}
	}
	if (bidir) {
		swap_info(&ipfw.ipfw, ipfw.ipfw.fw_proto == IPPROTO_ICMP);
		ret &= delete_entry(chain, &ipfw, ndaddrs, daddrs,
				    nsaddrs, saddrs, verbose, 0);
	}
	return ret;
}

static int
check_packet(const ip_chainlabel chain,
	     const struct ip_fwuser *fw,
	     unsigned int nsaddrs,
	     const struct in_addr saddrs[],
	     unsigned int ndaddrs,
	     const struct in_addr daddrs[],
	     int verbose,
	     int bidir)
{
	int ret = 1;
	unsigned int i, j;
	struct ip_fwuser ipfw = *fw;
	const char *msg;

	for (i = 0; i < nsaddrs; i++) {
		ipfw.ipfw.fw_src.s_addr = saddrs[i].s_addr;
		for (j = 0; j < ndaddrs; j++) {
			ipfw.ipfw.fw_dst.s_addr = daddrs[j].s_addr;
			if (verbose)
				print_firewall(stdout, &ipfw, 0, 0,
					       FMT_PRINT_RULE);
			msg = ipfwc_check_packet(chain, &ipfw.ipfw);
			if (!msg) ret = 0;
			else printf("%s\n", msg);
		}
	}

	if (bidir) {
		swap_info(&ipfw.ipfw, ipfw.ipfw.fw_proto == IPPROTO_ICMP);
		ret &= check_packet(chain, &ipfw, ndaddrs, daddrs,
				    nsaddrs, saddrs, verbose, 0);
	}

	return ret;
}

static int
for_each_chain(int (*fn)(const ip_chainlabel, int verbose),
	       int verbose, int userchains_only)
{
	unsigned int num_chains;
	int ret = 1;
	struct ipfwc_fwchain *chains = ipfwc_get_chainnames(&num_chains);

	if (chains) {
		unsigned int i = 0;
		for (i = 0; i < num_chains; i++) {
			if (!userchains_only ||
			    (strcmp(chains[i].label, IP_FW_LABEL_FORWARD) != 0
			     && strcmp(chains[i].label, IP_FW_LABEL_INPUT) != 0
			     && strcmp(chains[i].label, IP_FW_LABEL_OUTPUT) != 0))
			    ret &= fn(chains[i].label, verbose);
		}
	}
	else
	    ret = 0;

	return ret;
}

static int
flush_entries(const ip_chainlabel chain, int verbose)
{
	if (!chain) return for_each_chain(flush_entries, verbose, 0);
	else {
		if (verbose)
			fprintf(stdout, "Flushing chain `%s'\n", chain);
		return ipfwc_flush_entries(chain);
	}
}

static int
zero_entries(const ip_chainlabel chain, int verbose)
{
	if (!chain) return for_each_chain(zero_entries, verbose, 0);
	else {
		if (verbose)
			fprintf(stdout, "Zeroing chain `%s'\n", chain);
		return ipfwc_zero_entries(chain);
	}
}

static int
delete_chain(const ip_chainlabel chain, int verbose)
{
	if (!chain) return for_each_chain(delete_chain, verbose, 1);
	else {
		if (verbose)
			fprintf(stdout, "Deleting chain `%s'\n", chain);
		return ipfwc_delete_chain(chain);
	}
}

static int
list_entries(const ip_chainlabel chain, int zero, int verbose, int numeric,
	     int expanded)
{
	int format, found = 0;
	unsigned int num_rules, num_chains, i;
	struct ipfwc_fwchain *chains = ipfwc_get_chainnames(&num_chains);
	struct ipfwc_fwrule *rules;

	if (!chains)
		return 0;

	/* Impatience, hubris and laziness all in one line! */
	chains = memcpy(malloc(num_chains * sizeof(struct ipfwc_fwchain)),
			chains, num_chains * sizeof(struct ipfwc_fwchain));
	rules = ipfwc_get_rules(&num_rules, zero);
	if (!rules)
		return 0;

	format = FMT_OPTIONS | FMT_HEADER;
	if (!verbose)
		format |= FMT_NOCOUNTS;
	else format |= FMT_TOS | FMT_VIA | FMT_MARK | FMT_NETLINK;

	if (numeric)
		format |= FMT_NUMERIC;

	if (!expanded)
		format |= FMT_KILOMEGAGIGA;

	/* This is unreliable if a new chain is created and a rule
           added between ipfwc_get_chainnames and ipfwc_get_rules.
	*/
	for (i = 0; i < num_chains; i++) {
		if (!chain || strcmp(chain, chains[i].label) == 0) {
			int rulenum;

			found = 1;
			printf("Chain %s ", chains[i].label);
			if (strcmp(chains[i].policy, "-") == 0)
				printf("(%i references):",
				       chains[i].refcnt);
			else {
				printf("(policy %s",
				       chains[i].policy);
				if (!(format & FMT_NOCOUNTS))
					printf(": %llu packets, %llu bytes",
					       chains[i].packets,
					       chains[i].bytes);
				printf("):");
			}
			printf("\n");
			/* First one gets header. */
			format |= FMT_HEADER;
			for (rulenum = 0; rulenum < num_rules; rulenum++) {
				if (strcmp(rules[rulenum].chain->label, 
					   chains[i].label) == 0) {
					print_firewall(stdout, 
						       &rules[rulenum].ipfw,
						       rules[rulenum].bytes,
						       rules[rulenum].packets,
						       format);
					format &= ~FMT_HEADER;
				}
			}
		}
	}

	errno = ENOENT;
	return found;
}

int
ipfw_init(int args, char **arglist, unsigned int command, const char *chain, unsigned int rulenum)
{

	unsigned int nsaddrs = 0, ndaddrs = 0;
	struct in_addr *saddrs = NULL, *daddrs = NULL;

	int c;
	/* By declaring it static, it gets initialised to all 0. */
	static struct ip_fwuser fw;

	const char *jumpto = NULL;
	const char *srcpts = NULL, *dstpts = NULL;
	const char *shostnetworkmask = NULL, *dhostnetworkmask = NULL;
	const char *rport = "0";
	const char *policy = NULL;
	unsigned int options = 0;
	int ret = 1;
/*	program = arglist[0]; */
	program = "IPChains";

	/* static works great for single-programs, but in a module
	   the struct is not reinitialized */
        memset(&fw, 0, sizeof(fw));
       
	while ((c = getopt_long(args, arglist, "-o::p:s:d:j:i:fbvm:nlt:xy", opts, NULL)) != -1) {
		switch (c) {

			/*
			 * Option selection
			 */
		case 'p':
			if (check_inverse(optarg, &invert))
				optind++;
			set_option(&options, OPT_PROTOCOL, &fw.ipfw.fw_invflg);
			fw.ipfw.fw_proto = parse_protocol(arglist[optind-1]);
			if (fw.ipfw.fw_proto == 0
			    && (fw.ipfw.fw_invflg & IP_FW_INV_PROTO))
				exit_error(PARAMETER_PROBLEM,
					   "rule would never match protocol");
			break;

		case 's':
			if (check_inverse(optarg, &invert))
				optind++;
			set_option(&options, OPT_SOURCE, &fw.ipfw.fw_invflg);

			shostnetworkmask = arglist[optind-1];
			if (check_inverse(arglist[optind], &invert))
				optind++;
			if (optind < args && arglist[optind][0] != '-'
			    && arglist[optind][0] != '!')
			{
				srcpts = arglist[optind++];
				set_option(&options, OPT_SRCPT,
					   &fw.ipfw.fw_invflg);
			}
			break;

		case 'd':
			if (check_inverse(optarg, &invert))
				optind++;
			set_option(&options, OPT_DESTINATION,
				   &fw.ipfw.fw_invflg);

			dhostnetworkmask = arglist[optind-1];
			if (check_inverse(arglist[optind], &invert))
				optind++;
			if (optind < args && arglist[optind][0] != '-'
			    && arglist[optind][0] != '!')
			{
				dstpts = arglist[optind++];
				set_option(&options, OPT_DSTPT,
					   &fw.ipfw.fw_invflg);
			}
			break;

		case '1':
			if (check_inverse(optarg, &invert))
				optind++;
			set_option(&options, OPT_SRCPT, &fw.ipfw.fw_invflg);
			srcpts = optarg;
			break;

		case '2':
			if (check_inverse(optarg, &invert))
				optind++;
			set_option(&options, OPT_DSTPT, &fw.ipfw.fw_invflg);
			dstpts = optarg;
			break;

		case 'j':
			if (invert)
				exit_error(PARAMETER_PROBLEM,
					   "unexpected ! flag");
			set_option(&options, OPT_JUMP, &fw.ipfw.fw_invflg);
			jumpto = parse_target(optarg);
			if (strcmp(jumpto, IP_FW_LABEL_REDIRECT) == 0
			    && optind < args && arglist[optind][0] != '-'
			    && arglist[optind][0] != '!')
				rport = arglist[optind++];
			break;

		case 'i':
			if (check_inverse(optarg, &invert))
				optind++;
			set_option(&options, OPT_VIANAME, &fw.ipfw.fw_invflg);
			fw.ipfw.fw_flg |= parse_interface(arglist[optind-1],
							  fw.ipfw.fw_vianame);
			break;

		case 'f':
			set_option(&options, OPT_FRAGMENT, &fw.ipfw.fw_invflg);
			invert = FALSE;
			fw.ipfw.fw_flg |= IP_FW_F_FRAG;
			break;

		case 'b':
			if (invert)
				exit_error(PARAMETER_PROBLEM,
					   "unexpected ! flag");
			set_option(&options, OPT_BIDIR, &fw.ipfw.fw_invflg);
			break;

		case 'v':
			if (invert)
				exit_error(PARAMETER_PROBLEM,
					   "unexpected ! flag");
			set_option(&options, OPT_VERBOSE, &fw.ipfw.fw_invflg);
			break;

		case 'm':
			if (invert)
				exit_error(PARAMETER_PROBLEM,
					   "unexpected ! flag");
			set_option(&options, OPT_MARK, &fw.ipfw.fw_invflg);
			fw.ipfw.fw_flg |= parse_mark(optarg, &fw.ipfw.fw_mark);
			break;

		case 'n':
			if (invert)
				exit_error(PARAMETER_PROBLEM,
					   "unexpected ! flag");
			set_option(&options, OPT_NUMERIC, &fw.ipfw.fw_invflg);
			break;

		case 'l':
			if (invert)
				exit_error(PARAMETER_PROBLEM,
					   "unexpected ! flag");
			set_option(&options, OPT_PRINTK, &fw.ipfw.fw_invflg);
			fw.ipfw.fw_flg |= IP_FW_F_PRN;
			break;

		case 'o':
			if (invert)
				exit_error(PARAMETER_PROBLEM,
					   "unexpected ! flag");
			set_option(&options, OPT_NETLINK, &fw.ipfw.fw_invflg);
			if (!optarg && optind < args && arglist[optind][0] != '-'
			    && arglist[optind][0] != '!')
				optarg = arglist[optind++];

			fw.ipfw.fw_flg
				|= parse_outputsize(optarg,
						    &fw.ipfw.fw_outputsize);
			break;

		case 't':
			if (invert)
				exit_error(PARAMETER_PROBLEM,
					   "unexpected ! flag");
			set_option(&options, OPT_TOS, &fw.ipfw.fw_invflg);
			if (optind < args && arglist[optind][0] != '-'
			    && arglist[optind][0] != '!') {
				parse_hexbyte(optarg, &fw.ipfw.fw_tosand);
				parse_hexbyte(arglist[optind++],
					      &fw.ipfw.fw_tosxor);
				check_tos(fw.ipfw.fw_tosand,
					  fw.ipfw.fw_tosxor);
			} else
				exit_error(PARAMETER_PROBLEM,
					   "-%c requires 2 hexbyte arguments",
					   opt2char(OPT_TOS));
			break;

		case 'x':
			if (invert)
				exit_error(PARAMETER_PROBLEM,
					   "unexpected ! flag");
			set_option(&options, OPT_EXPANDED, &fw.ipfw.fw_invflg);
			break;

		case 'y':
			set_option(&options, OPT_TCPSYN, &fw.ipfw.fw_invflg);
			fw.ipfw.fw_flg |= IP_FW_F_TCPSYN;
			invert = FALSE;
			break;

		case 1: /* non option */
			if (optarg[0] == '!' && optarg[1] == '\0') {
				if (invert)
					exit_error(PARAMETER_PROBLEM,
						   "multiple consecutive ! not allowed\n");
				invert = TRUE;
				optarg[0] = '\0';
				continue;
			}
			/* FALL THOUGH */

		}

		invert = FALSE;
	}

	if (optind < args)
		exit_error(PARAMETER_PROBLEM,
			   "unknown arguments found on commandline");
	else if (!command)
		exit_error(PARAMETER_PROBLEM, "no command specified");
	else if (invert)
		exit_error(PARAMETER_PROBLEM,
			   "nothing appropriate following !");

	if ((command & CMD_REPLACE)
	    || (command & CMD_INSERT)
	    || (command & CMD_DELETE)
	    || (command & CMD_APPEND)) {
		if (!(options & OPT_DESTINATION))
			dhostnetworkmask = "0.0.0.0/0";
		if (!(options & OPT_SOURCE))
			shostnetworkmask = "0.0.0.0/0";
	}

	if (shostnetworkmask) {
		parse_hostnetworkmask(shostnetworkmask, &saddrs,
			&(fw.ipfw.fw_smsk), &nsaddrs);
		if (fw.ipfw.fw_proto != IPPROTO_ICMP)
			parse_ports(srcpts, fw.ipfw.fw_spts, fw.ipfw.fw_proto);
	}

	if (dhostnetworkmask) {
		parse_hostnetworkmask(dhostnetworkmask, &daddrs,
			&(fw.ipfw.fw_dmsk), &ndaddrs);
		if (fw.ipfw.fw_proto != IPPROTO_ICMP)
			parse_ports(dstpts, fw.ipfw.fw_dpts, fw.ipfw.fw_proto);
	}

	if (fw.ipfw.fw_proto == IPPROTO_ICMP) {
		parse_icmp(srcpts, dstpts, fw.ipfw.fw_spts, fw.ipfw.fw_dpts,
			   &options, fw.ipfw.fw_invflg, command == CMD_CHECK);
	}

	if ((nsaddrs > 1 || ndaddrs > 1) &&
	    (fw.ipfw.fw_invflg & (IP_FW_INV_SRCIP | IP_FW_INV_DSTIP)))
		exit_error(PARAMETER_PROBLEM, "! not allowed with multiple source or destination IP addresses");

	if ((nsaddrs > 1 || ndaddrs > 1) && (options & OPT_BIDIR))
		exit_error(PARAMETER_PROBLEM, "-b not allowed with multiple source or destination IP addresses");

	if ((fw.ipfw.fw_proto == 0 || (fw.ipfw.fw_invflg & IP_FW_INV_PROTO))
	    && ((options & OPT_SRCPT) || (options & OPT_DSTPT)))
		exit_error(PARAMETER_PROBLEM, "no ports allowed without specific protocol");

	if ((fw.ipfw.fw_proto != IPPROTO_TCP
	     || (fw.ipfw.fw_invflg & IP_FW_INV_PROTO))
	    && (options & OPT_TCPSYN))
		exit_error(PARAMETER_PROBLEM, "-%c only allowed with TCP protocol",
			   opt2char(OPT_TCPSYN));

	if ((options & OPT_FRAGMENT) && !(fw.ipfw.fw_invflg & IP_FW_INV_FRAG)
	    && ((options & OPT_SRCPT) || (options & OPT_DSTPT)))
		exit_error(PARAMETER_PROBLEM, "no ports allowed with -%c",
			   opt2char(OPT_FRAGMENT));

	if ((options & OPT_FRAGMENT) && !(fw.ipfw.fw_invflg & IP_FW_INV_FRAG)
	    && (options & OPT_TCPSYN))
		exit_error(PARAMETER_PROBLEM, "-%c not allowed with -%c",
			   opt2char(OPT_TCPSYN), opt2char(OPT_FRAGMENT));

	if (command == CMD_CHECK
	    && (fw.ipfw.fw_proto == IPPROTO_TCP
		|| fw.ipfw.fw_proto == IPPROTO_UDP
		|| fw.ipfw.fw_proto == IPPROTO_ICMP)
	    && !(options & OPT_FRAGMENT)
	    && (!(options & OPT_SRCPT)
		|| fw.ipfw.fw_spts[0] != fw.ipfw.fw_spts[1]
		|| !(options & OPT_DSTPT)
		|| fw.ipfw.fw_dpts[0] != fw.ipfw.fw_dpts[1]))
		exit_error(PARAMETER_PROBLEM, "one port required with source/destination "
			   "address for -%c", cmd2char(CMD_CHECK));

	if (command == CMD_CHECK && fw.ipfw.fw_invflg != 0)
		exit_error(PARAMETER_PROBLEM, "! not allowed with -%c", cmd2char(CMD_CHECK));

	if (((fw.ipfw.fw_proto != IPPROTO_TCP && fw.ipfw.fw_proto != IPPROTO_UDP)
	     || (fw.ipfw.fw_invflg & IP_FW_INV_PROTO))
	    && jumpto && strcmp(jumpto, IP_FW_LABEL_REDIRECT) == 0)
		exit_error(PARAMETER_PROBLEM, "redirecting only allowed with TCP or UDP");

	if (jumpto && strcmp(jumpto, IP_FW_LABEL_MASQUERADE) == 0
	    && chain && (strcmp(chain, IP_FW_LABEL_INPUT) == 0
			 || strcmp(chain, IP_FW_LABEL_OUTPUT) == 0))
		exit_error(PARAMETER_PROBLEM,
			   "masquerading not allowed for input and output chains");

	if (jumpto && strcmp(jumpto, IP_FW_LABEL_REDIRECT) == 0
	    && chain && (strcmp(chain, IP_FW_LABEL_OUTPUT) == 0
			 || strcmp(chain, IP_FW_LABEL_FORWARD) == 0))
		exit_error(PARAMETER_PROBLEM,
			   "redirect not allowed for output and forward chains");

	if (command == CMD_REPLACE && (nsaddrs != 1 || ndaddrs != 1))
		exit_error(PARAMETER_PROBLEM, "Replacement rule does not "
			   "specify a unique address");

	/* Allow lazy -S without -M */
	if (command == CMD_SET_MASQUERADE)
	    command |= CMD_MASQUERADE;

	generic_opt_check(command, options);

	if (chain && strlen(chain) > IP_FW_MAX_LABEL_LENGTH)
		exit_error(PARAMETER_PROBLEM,
			   "chain name `%s' too long (must be under %i chars)",
			   chain, IP_FW_MAX_LABEL_LENGTH);

	if (jumpto && strcmp(jumpto, IP_FW_LABEL_REDIRECT) == 0) {
		fw.ipfw.fw_redirpt = parse_port(rport, fw.ipfw.fw_proto);
	}

	if (!(options & OPT_TOS)) {
		fw.ipfw.fw_tosand = 0xFF;
		fw.ipfw.fw_tosxor = 0x00;
	}

	if (options & OPT_JUMP)
		strcpy(fw.label, jumpto);

	if (command == CMD_MASQUERADE)
		exit_error(PARAMETER_PROBLEM,
			   "-M/--masquerading requires -L/--list or -S/--set");

	switch (command) {
	case CMD_APPEND:
		ret = append_entry(chain, &fw,
				   nsaddrs, saddrs, ndaddrs, daddrs,
				   options&OPT_VERBOSE,
				   options&OPT_BIDIR);
		break;
	case CMD_CHECK:
		ret = check_packet(chain, &fw,
				   nsaddrs, saddrs, ndaddrs, daddrs,
				   options&OPT_VERBOSE,
				   options&OPT_BIDIR);
		break;
	case CMD_DELETE:
		ret = delete_entry(chain, &fw,
				   nsaddrs, saddrs, ndaddrs, daddrs,
				   options&OPT_VERBOSE,
				   options&OPT_BIDIR);
		break;
	case CMD_DELETE_NUM:
		ret = ipfwc_delete_num_entry(chain, rulenum);
		break;
	case CMD_REPLACE:
		ret = replace_entry(chain, &fw, rulenum,
				    saddrs, daddrs, options&OPT_VERBOSE);
		break;
	case CMD_INSERT:
		ret = insert_entry(chain, &fw, rulenum,
				   nsaddrs, saddrs, ndaddrs, daddrs,
				   options&OPT_VERBOSE,
				   options&OPT_BIDIR);
		break;
	case CMD_LIST|CMD_MASQUERADE:
		ret = list_masq(options);
		break;
	case CMD_LIST:
	case CMD_LIST|CMD_ZERO:
		ret = list_entries(chain, command&CMD_ZERO,
				   options&OPT_VERBOSE,
				   options&OPT_NUMERIC,
				   options&OPT_EXPANDED);
		break;
	case CMD_FLUSH:
		ret = flush_entries(chain, options&OPT_VERBOSE);
		break;
	case CMD_ZERO:
		ret = zero_entries(chain, options&OPT_VERBOSE);
		break;
	case CMD_NEW_CHAIN:
		ret = ipfwc_create_chain(chain);
		break;
	case CMD_DELETE_CHAIN:
		ret = delete_chain(chain, options&OPT_VERBOSE);
		break;
	case CMD_MASQUERADE|CMD_SET_MASQUERADE: {
		int sockfd;
		if ((sockfd = socket(AF_INET, SOCK_RAW, IPPROTO_RAW)) == -1) {
			perror("ipchains: socket creation failed");
			exit(1);
		}

		if (setsockopt(sockfd, IPPROTO_IP, IP_FW_MASQ_TIMEOUTS,
			       (char *) &timeouts, sizeof(timeouts)) != 0) {
			perror("ipchains: setting MASQ timeouts failed");
			exit(1);
		}
		close(sockfd);
		ret = 1;
		break;
	}
	case CMD_SET_POLICY:
		policy = parse_policy(chain, arglist[1]);
		ret = ipfwc_set_policy(chain, policy);
		break;
	default:
		/* We should never reach this... */
		exit_tryhelp(2);
	}

	if (!ret)
		fprintf(stderr, "ipchains: %s\n", ipfwc_strerror(errno));
	return(!ret);
}

/* adapted interface code begin */

int
ipfw_append(int args, char **arglist, const char *chain)
{
	unsigned int command = 0;
	add_command(&command, CMD_APPEND, CMD_NONE);
	ipfw_init(args, arglist, command, chain, 0);
	optind = 0;
	return(0);
}

int
ipfw_delete(int args, char **arglist, const char *chain, unsigned int rulenum)
{
	unsigned int command = 0;
	add_command(&command, CMD_DELETE, CMD_NONE);
	command = CMD_DELETE_NUM;
	ipfw_init(args, arglist, command, chain, rulenum);
	optind = 0;
	return(0);
}

int
ipfw_check(int args, char **arglist, const char *chain)
{
	unsigned int command = 0;
	add_command(&command, CMD_CHECK, CMD_NONE);
	ipfw_init(args, arglist, command, chain, 0);
	optind = 0;
	return(0);
}

int
ipfw_replace(int args, char **arglist, const char *chain, unsigned int rulenum)
{
	unsigned int command = 0;
	add_command(&command, CMD_REPLACE, CMD_NONE);
	ipfw_init(args, arglist, command, chain, rulenum);
	optind = 0;
	return(0);
}

int
ipfw_insert(int args, char **arglist, const char *chain, unsigned int rulenum)
{
	unsigned int command = 0;
	add_command(&command, CMD_INSERT, CMD_NONE);
	if(!rulenum)
		rulenum = 1;
	ipfw_init(args, arglist, command, chain, rulenum);
	optind = 0;
	return(0);
}

int
ipfw_list(int args, char **arglist, const char *chain)
{
	unsigned int command = 0;
	add_command(&command, CMD_LIST, CMD_ZERO|CMD_MASQUERADE);
	ipfw_init(args, arglist, command, chain, 0);
	optind = 0;
	return(0);
}

int
ipfw_flush(int args, char **arglist, const char *chain)
{
	unsigned int command = 0;
	add_command(&command, CMD_FLUSH, CMD_NONE);
	ipfw_init(args, arglist, command, chain, 0);
	optind = 0;
	return(0);
}

int
ipfw_zero(int args, char **arglist)
{
	unsigned int command = 0;
	add_command(&command, CMD_ZERO, CMD_LIST);
	ipfw_init(args, arglist, command, NULL, 0);
	optind = 0;
	return(0);
}

int
ipfw_new_chain(int args, char **arglist, const char *chain)
{
	unsigned int command = 0;
	add_command(&command, CMD_NEW_CHAIN, CMD_NONE);
	ipfw_init(args, arglist, command, chain, 0);
	optind = 0;
	return(0);
}

int
ipfw_del_chain(int args, char **arglist, const char *chain)
{
	unsigned int command = 0;
	add_command(&command, CMD_DELETE_CHAIN, CMD_NONE);
	ipfw_init(args, arglist, command, chain, 0);
	optind = 0;
	return(0);
}

int
ipfw_set_policy(int args, char **arglist, const char *chain)
{
	unsigned int command = 0;
	add_command(&command, CMD_SET_POLICY, CMD_NONE);
	ipfw_init(args, arglist, command, chain, 0);
	optind = 0;
	return(0);
}	
	
int
ipfw_masq(int args, char **arglist)
{
	unsigned int command = 0;
	add_command(&command, CMD_MASQUERADE, CMD_LIST|CMD_SET_MASQUERADE);
	add_command(&command, CMD_LIST, CMD_ZERO|CMD_MASQUERADE);
	ipfw_init(args, arglist, command, NULL, 0);
	optind = 0;
	return(0);
}


/* adapted interface code end */

static 
int check_inverse(const char option[], int *invert)
{
	if (option && strcmp(option, "!") == 0) {
		if (*invert)
			exit_error(PARAMETER_PROBLEM, "Multiple `!' flags not allowed");

		*invert = TRUE;
		return TRUE;
	}
	return FALSE;
}

/*
 *	All functions starting with "parse" should succeed, otherwise
 *	the program fails.
 *	Most routines return pointers to static data that may change
 *	between calls to the same or other routines with a few exceptions:
 *	"host_to_addr", "parse_hostnetwork", and "parse_hostnetworkmask"
 *	return global static data.
*/

static struct in_addr *
parse_hostnetwork(const char *name, unsigned int *naddrs)
{
	struct in_addr *addrp, *addrptmp;

	if ((addrptmp = dotted_to_addr(name)) != NULL) {
		addrp = fw_malloc(sizeof(struct in_addr));
		inaddrcpy(addrp, addrptmp);
		*naddrs = 1;
		return addrp;
	} else if ((addrptmp = network_to_addr(name)) != NULL) {
		addrp = fw_malloc(sizeof(struct in_addr));
		inaddrcpy(addrp, addrptmp);
		*naddrs = 1;
		return addrp;
	} else if ((addrp = host_to_addr(name, naddrs)) != NULL) {
		return addrp;
	} else
		exit_error(PARAMETER_PROBLEM, "host/network `%s' not found", name);
}

static void
parse_hostnetworkmask(const char *name, struct in_addr **addrpp,
		struct in_addr *maskp, unsigned int *naddrs)
{
	struct in_addr *addrp;
	char buf[256];
	char *p;
	int i, j, k, n;

	strncpy(buf, name, sizeof(buf) - 1);
	if ((p = strrchr(buf, '/')) != NULL) {
		*p = '\0';
		addrp = parse_mask(p + 1);
	} else
		addrp = parse_mask(NULL);
	inaddrcpy(maskp, addrp);

	/* if a null mask is given, the name is ignored, like in "any/0" */
	if (maskp->s_addr == 0L)
		strcpy(buf, "0.0.0.0");

	addrp = *addrpp = parse_hostnetwork(buf, naddrs);
	n = *naddrs;
	for (i = 0, j = 0; i < n; i++) {
		addrp[j++].s_addr &= maskp->s_addr;
		for (k = 0; k < j - 1; k++) {
			if (addrp[k].s_addr == addrp[j - 1].s_addr) {
				(*naddrs)--;
				j--;
				break;
			}
		}
	}
}

static struct in_addr *
parse_mask(char *mask)
{
	static struct in_addr maskaddr;
	struct in_addr *addrp;
	int bits;

	if (mask == NULL) {
		/* no mask at all defaults to 32 bits */
		maskaddr.s_addr = 0xFFFFFFFF;
		return &maskaddr;
	} else if ((addrp = dotted_to_addr(mask)) != NULL) {
		/* dotted_to_addr already returns a network byte order addr */
		return addrp;
	} else if ((bits = string_to_number(mask, 0, 32)) == -1) {
		exit_error(PARAMETER_PROBLEM, "invalid mask `%s' specified", mask);
	} else if (bits != 0) {
		maskaddr.s_addr = htonl(0xFFFFFFFF << (32 - bits));
		return &maskaddr;
	} else {
		maskaddr.s_addr = 0L;
		return &maskaddr;
	}
}

static const char *
parse_policy(const char *chain, const char *policy)
{
    if (strcmp(policy, IP_FW_LABEL_MASQUERADE) == 0) {
	if (strcmp(chain, IP_FW_LABEL_FORWARD) != 0)
	    exit_error(PARAMETER_PROBLEM,
		       "`-%c %s' only valid for `%s' chain.",
		       cmd2char(CMD_SET_POLICY),
		       IP_FW_LABEL_MASQUERADE,
		       IP_FW_LABEL_FORWARD);
	else return policy;
    }

    if (strcmp(chain, IP_FW_LABEL_INPUT) != 0
	&& strcmp(chain, IP_FW_LABEL_OUTPUT) != 0
	&& strcmp(chain, IP_FW_LABEL_FORWARD) != 0)
	exit_error(PARAMETER_PROBLEM,
		   "Can only set policy in built-in chains.");

    if (strcmp(policy, IP_FW_LABEL_ACCEPT) != 0
	&& strcmp(policy, IP_FW_LABEL_BLOCK) != 0
	&& strcmp(policy, IP_FW_LABEL_REJECT) != 0)
	exit_error(PARAMETER_PROBLEM, "Invalid policy `%s' for -%c", policy,
		   cmd2char(CMD_SET_POLICY));

    return policy;
}

/* A few hardcoded protocols for 'all' and in case the user has no
   /etc/protocols */
struct pprot {
	char *name;
	unsigned short num;
};

static const struct pprot chain_protos[] = {
	{ "all", 0 },
	{ "tcp", IPPROTO_TCP },
	{ "udp", IPPROTO_UDP },
	{ "icmp", IPPROTO_ICMP },
	{0}
};

static unsigned short int
parse_protocol(const char *s)
{
	struct protoent *pent;
	const struct pprot *pp;

	int proto = string_to_number(s, 0, 65535);

	if (proto != -1) return (unsigned short)proto;

	pent = getprotobyname(s);
	if (pent != NULL)
		return pent->p_proto;

	for (pp = &chain_protos[0]; pp->name; pp++)
		if (!strcasecmp(s, pp->name))
			return pp->num;

	exit_error(PARAMETER_PROBLEM, "unknown protocol `%s' specified", s);
}

static char *
proto_to_name(unsigned short proto)
{
	const struct pprot *pp;

	if (proto) {
		struct protoent *pent = getprotobynumber(proto);
		if (pent)
			return pent->p_name;
	}

	for (pp = &chain_protos[0]; pp->name; pp++)
		if (pp->num == proto)
			return pp->name;

	return NULL;
}

static void
parse_icmp(const char *srcportstring, const char *dstportstring,
	   __u16 *type, __u16* code, int *options, __u16 invflags,
	   int checking)
{
	if (srcportstring) {
		const unsigned int limit
			= sizeof(icmp_codes)/sizeof(struct icmp_names);
		unsigned int match = limit;
		unsigned int i;

		for (i = 0; i < limit; i++) {
			if (strncasecmp(icmp_codes[i].name, srcportstring,
					strlen(srcportstring)) == 0) {
				if (match != limit)
					exit_error(PARAMETER_PROBLEM, "Ambiguous ICMP `%s' : "
						   "`%s' or `%s'?",
						   srcportstring,
						   icmp_codes[match].name,
						   icmp_codes[i].name);
				match = i;
			}
		}

		if (match != limit) {
			if (dstportstring)
				exit_error(PARAMETER_PROBLEM, "Can't use ICMP name and destination port together");
			*options |= OPT_DSTPT;
			type[0] = type[1] = icmp_codes[match].type;
			code[0] = icmp_codes[match].code_min;
			code[1] = icmp_codes[match].code_max;
			if (checking) {
				if (icmp_codes[match].use_code_min_for_testing)
					code[1] = code[0];
				else if (code[0] != code[1])
					exit_error(PARAMETER_PROBLEM, "Must specify exact ICMP type for testing");
			}

			/* Inverting won't do what they think it will do. */
			if (invflags & (IP_FW_INV_SRCPT | IP_FW_INV_DSTPT))
				exit_error(PARAMETER_PROBLEM, "Can't invert named ICMP types");

			return;
		}
	}
	parse_ports(srcportstring, type, IPPROTO_ICMP);
	parse_ports(dstportstring, code, IPPROTO_ICMP);
}

static void
parse_ports(const char *portstring, __u16 *ports, __u16 proto)
{
	char *buffer;
	char *cp;

	if (portstring == NULL) {
		ports[0] = 0;
		ports[1] = 0xFFFF;
		return;
	}

	buffer = strdup(portstring);
	if ((cp = strchr(buffer, ':')) == NULL) {
		ports[0] = ports[1] = parse_port(buffer, proto);
	}
	else {
		*cp = '\0';
		cp++;

		ports[0] = buffer[0] ? parse_port(buffer, proto) : 0;
		ports[1] = cp[0] ? parse_port(cp, proto) : 0xFFFF;
	}
	free(buffer);
}

static unsigned short
parse_mark(char *markstring, __u32 *mark)
{
	char *end, *ptr;
	unsigned long l;

	if (*markstring == '-' || *markstring == '+')
		ptr = markstring+1;
	else ptr = markstring;

	l = strtoul(ptr, &end, 0);

	if (end[0] != '\0' || end == ptr || l > UINT_MAX)
		exit_error(PARAMETER_PROBLEM, "Bad value `%s' for -%c.\n",
			   markstring, opt2char(OPT_MARK));

	/* This gives the effect of subtraction in the kernel */
	if (*markstring == '-')
		*mark = (__u32)(-(__s32)l);
	else *mark = (__u32)l;

	if (*markstring == '-' || *markstring == '+')
		return 0;
	else return IP_FW_F_MARKABS;
}

static unsigned short
parse_outputsize(char *outputstring, __u16 *outputsize)
{
	if (!outputstring) {
		*outputsize = 65535;
	}
	else {
		int i = string_to_number(outputstring, 0, 65535);
		if (i == -1)
			exit_error(PARAMETER_PROBLEM, "-o argument must be 0-65535, not `%s'",
				   outputstring);
		*outputsize = (__u16)i;
	}
	return IP_FW_F_NETLINK;
}

static unsigned short
parse_interface(const char *ifstring, char *vianame)
{
	if (strlen(ifstring) > IFNAMSIZ)
		exit_error(PARAMETER_PROBLEM, "interface name `%s' must be shorter than IFNAMSIZ (%i)",
			   ifstring, IFNAMSIZ);

	strncpy(vianame, ifstring, IFNAMSIZ);
	if (vianame[0] == '\0')
		return IP_FW_F_WILDIF;
	else if(vianame[strlen(ifstring)-1] == '+') {
		vianame[strlen(ifstring)-1] = '\0';
		return IP_FW_F_WILDIF;
	}
	else return 0;
}

static __u16
parse_port(const char *port, unsigned short proto)
{
	int portnum;

	if (proto != IPPROTO_ICMP
	    && proto != IPPROTO_TCP
	    && proto != IPPROTO_UDP)
		exit_error(PARAMETER_PROBLEM, "can only specify ports for icmp, tcp or udp");
	else if ((portnum = string_to_number(port, 0, 65535)) != -1)
		return (unsigned short) portnum;
	else if (proto == IPPROTO_ICMP) {
		/* ICMP types (given as port numbers) must be numeric! */
		exit_error(PARAMETER_PROBLEM, "invalid ICMP type `%s' specified", port);
	} else if ((portnum = service_to_port(port, proto)) != -1)
		return (unsigned short) portnum;
	else {
		exit_error(PARAMETER_PROBLEM, "invalid port/service `%s' specified", port);
	}
}

/* Can't be zero. */
static int
parse_rulenumber(const char *rule)
{
	int rulenum = string_to_number(rule, 1, INT_MAX);
	if (rulenum == -1) exit_error(PARAMETER_PROBLEM, "Invalid rule number `%s'", rule);

	return rulenum;
}

static void
parse_hexbyte(char *s, unsigned char *b)
{
	long number;
	char *end;

	number = strtol(s, &end, 16);
	if (*end == '\0' && end != s) {
		/* we parsed a number, let's see if we want this */
		if (0 <= number && number <= 255)
			*b = (unsigned char) number;
		else {
			exit_error(PARAMETER_PROBLEM, "invalid hexbyte `%s' specified", s);
		}
	} else {
		exit_error(PARAMETER_PROBLEM, "invalid hexbyte `%s' specified", s);
	}
}

static int
parse_timeout(char *s)
{
	int timeout;

	if ((timeout = string_to_number(s, 0, INT_MAX)) != -1)
		return timeout;
	else
		exit_error(PARAMETER_PROBLEM, "invalid timeout value `%s' specified", s);
}

static const char *
parse_target(const char *targetname)
{
	const char *ptr;
	if (targetname == NULL || strlen(targetname) < 1)
		exit_error(PARAMETER_PROBLEM, "Invalid target name (too short)");

	if (strlen(targetname)+1 > sizeof(ip_chainlabel))
		exit_error(PARAMETER_PROBLEM, "Invalid target name `%s' (%i chars max)",
			   targetname, sizeof(ip_chainlabel)-1);

	for (ptr = targetname; *ptr; ptr++)
		if (isspace(*ptr)) exit_error(PARAMETER_PROBLEM, "Invalid target name `%s'",
					      targetname);

	return targetname;
}

static struct in_addr *
host_to_addr(const char *name, unsigned int *naddr)
{
	struct hostent *host;
	struct in_addr *addr;
	unsigned int i;

	*naddr = 0;
	if ((host = gethostbyname(name)) != NULL) {
		if (host->h_addrtype != AF_INET ||
				host->h_length != sizeof(struct in_addr))
			return (struct in_addr *) NULL;
		while (host->h_addr_list[*naddr] != (char *) NULL)
			(*naddr)++;
		addr = fw_calloc(*naddr, sizeof(struct in_addr));
		for (i = 0; i < *naddr; i++)
			inaddrcpy(&(addr[i]), (struct in_addr *) host->h_addr_list[i]);
		return addr;
	} else
		return (struct in_addr *) NULL;
}

static char *
addr_to_host(struct in_addr *addr)
{
	struct hostent *host;

	if ((host = gethostbyaddr((char *) addr,
			sizeof(struct in_addr), AF_INET)) != NULL)
		return (char *) host->h_name;
	else
		return (char *) NULL;
}

static struct in_addr *
network_to_addr(const char *name)
{
	struct netent *net;
	static struct in_addr addr;

	if ((net = getnetbyname(name)) != NULL) {
		if (net->n_addrtype != AF_INET)
			return (struct in_addr *) NULL;
		addr.s_addr = htonl((unsigned long) net->n_net);
		return &addr;
	} else
		return (struct in_addr *) NULL;
}

static char *
addr_to_network(struct in_addr *addr)
{
	struct netent *net;

	if ((net = getnetbyaddr((long) ntohl(addr->s_addr), AF_INET)) != NULL)
		return (char *) net->n_name;
	else
		return (char *) NULL;
}

static char *
addr_to_anyname(struct in_addr *addr)
{
	char *name;

	if ((name = addr_to_host(addr)) != NULL)
		return name;
	else if ((name = addr_to_network(addr)) != NULL)
		return name;
	else
		return addr_to_dotted(addr);
}

static struct in_addr *
dotted_to_addr(const char *dotted)
{
	static struct in_addr addr;
	unsigned char *addrp;
	char *p, *q;
	int onebyte, i;
	char buf[20];

	/* copy dotted string, because we need to modify it */
	strncpy(buf, dotted, sizeof(buf) - 1);
	addrp = (unsigned char *) &(addr.s_addr);

	p = buf;
	for (i = 0; i < 3; i++) {
		if ((q = strchr(p, '.')) == NULL)
			return (struct in_addr *) NULL;
		else {
			*q = '\0';
			if ((onebyte = string_to_number(p, 0, 255)) == -1)
				return (struct in_addr *) NULL;
			else
				addrp[i] = (unsigned char) onebyte;
		}
		p = q + 1;
	}

	/* we've checked 3 bytes, now we check the last one */
	if ((onebyte = string_to_number(p, 0, 255)) == -1)
		return (struct in_addr *) NULL;
	else
		addrp[3] = (unsigned char) onebyte;

	return &addr;
}

static char *
addr_to_dotted(struct in_addr *addrp)
{
	static char buf[20];
	unsigned char *bytep;

	bytep = (unsigned char *) &(addrp->s_addr);
	sprintf(buf, "%d.%d.%d.%d", bytep[0], bytep[1], bytep[2], bytep[3]);
	return buf;
}

static char *
mask_to_dotted(struct in_addr *mask)
{
	int i;
	static char buf[20];
	__u32 maskaddr, bits;

	maskaddr = ntohl(mask->s_addr);

	if (maskaddr == 0xFFFFFFFFL)
		/* we don't want to see "/32" */
		return "";
	else {
		i = 32;
		bits = 0xFFFFFFFEL;
		while (--i >= 0 && maskaddr != bits)
			bits <<= 1;
		if (i >= 0)
			sprintf(buf, "/%d", i);
		else
			/* mask was not a decent combination of 1's and 0's */
			sprintf(buf, "/%s", addr_to_dotted(mask));
		return buf;
	}
}

static int
service_to_port(const char *name, unsigned short proto)
{
	struct servent *service;

	if (proto == IPPROTO_TCP
	    && (service = getservbyname(name, "tcp")) != NULL)
		return ntohs((unsigned short) service->s_port);
	else if (proto == IPPROTO_UDP
		 && (service = getservbyname(name, "udp")) != NULL)
		return ntohs((unsigned short) service->s_port);
	else
		return -1;
}

static char *
port_to_service(int port, unsigned short proto)
{
	struct servent *service;

	if (proto == IPPROTO_TCP &&
			(service = getservbyport(htons(port), "tcp")) != NULL)
		return service->s_name;
	else if (proto == IPPROTO_UDP &&
			(service = getservbyport(htons(port), "udp")) != NULL)
		return service->s_name;
	else
		return (char *) NULL;
}

static int
string_to_number(const char *s, int min, int max)
{
	int number;
	char *end;

	number = (int)strtol(s, &end, 10);
	if (*end == '\0' && end != s) {
		/* we parsed a number, let's see if we want this */
		if (min <= number && number <= max)
			return number;
		else
			return -1;
	} else
		return -1;
}

static int
list_masq(unsigned int options)
{
	FILE *fp;
	int i;
	char buf[256];
	struct masq *mslist;
	int ntotal = 0, nread, format;

	if ((fp = fopen("/proc/net/ip_masquerade", "r")) == NULL)
		exit_error(OTHER_PROBLEM, "cannot open file `/proc/net/ip_masquerade'");

	if (fgets(buf, sizeof(buf), fp) == NULL)
		exit_error(VERSION_PROBLEM,
			   "unexpected input from `/proc/net/ip_masquerade'");
	fputs("IP masquerading entries\n", stdout);

	mslist = (struct masq *) fw_malloc(16 * sizeof(struct masq));
	while ((nread = read_masqinfo(fp, &(mslist[ntotal]), 16)) == 16) {
		ntotal += nread;
		mslist = (struct masq *) fw_realloc(mslist,
			(ntotal + 16) * sizeof(struct masq));
	}
	ntotal += nread;
	fclose(fp);

	format = 0;

	if (options & OPT_NUMERIC)
		format |= FMT_NUMERIC;

	if (options & OPT_VERBOSE)
		format |= FMT_DELTAS;

	if (ntotal > 0)
		for (i = 0; i < ntotal; i++)
			print_masq(stdout, &(mslist[i]),
				(i) ? format : (format | FMT_HEADER));

	free(mslist);
	return 1;
}

static void
print_port(FILE *fp, int numeric, __u16 port, __u16 proto)
{
	char *service;
	if (numeric || (service = port_to_service(port, proto)) == NULL)
		fprintf(fp, "%u", port);
	else
		fputs(service, fp);
}

static void
print_firewall(FILE *fp,
	       struct ip_fwuser *fw,
	       __u64 bytes, __u64 packets,
	       int format)
{
	unsigned short flags;
	__u64 cnt, cntkb, cntmb, cntgb;
	char buf[BUFSIZ];
	flags = fw->ipfw.fw_flg;

#define FMT(tab,notab) ((format & FMT_NOTABLE) ? notab : tab)

	if (format & FMT_HEADER) {
		if (!(format & FMT_NOCOUNTS)) {
			if (format & FMT_KILOMEGAGIGA) {
				fprintf(fp, FMT("%5s ","%s "), "pkts");
				fprintf(fp, FMT("%5s ","%s "), "bytes");
			} else {
				fprintf(fp, FMT("%8s ","%s "), "pkts");
				fprintf(fp, FMT("%10s ","%s "), "bytes");
			}
		}
		if (!(format & FMT_NOTARGET)) {
			fprintf(fp, FMT("%-9s ","%s "), "target");
		}
		fputs(" prot ", fp);
		if (format & FMT_OPTIONS)
			fputs("opt    ", fp);
		if (format & FMT_TOS)
			fputs("tosa tosx ", fp);
		if (format & FMT_VIA)
			fprintf(fp, FMT(" %-10s ","%s "), "ifname");
		if (format & FMT_MARK)
			fprintf(fp, FMT("%-10s ","%s "), "mark");
		if (format & FMT_NETLINK)
			fprintf(fp, FMT("%-7s ","%s "), "outsize");
		fprintf(fp, FMT(" %-20s ","%s "), "source");
		fprintf(fp, FMT(" %-20s ","%s "), "destination");
		fputs(" ports\n", fp);
	}

	if (!(format & FMT_NOCOUNTS)) {
		cnt = packets;
		if (format & FMT_KILOMEGAGIGA) {
			if (cnt > 99999) {
				cntkb = (cnt + 500) / 1000;
				if (cntkb > 9999) {
					cntmb = (cnt + 500000) / 1000000;
					if (cntmb > 9999) {
						cntgb = (cntmb + 500) / 1000;
						fprintf(fp,
							FMT("%4lluG ","%lluG "),
							cntgb);
					}
					else
						fprintf(fp, FMT("%4lluM ","%lluM "), cntmb);
				} else
					fprintf(fp, FMT("%4lluK ","%lluK "), cntkb);
			} else
				fprintf(fp, FMT("%5llu ","%llu "), cnt);
		} else
			fprintf(fp, FMT("%8llu ","%llu "), cnt);
		cnt = bytes;
		if (format & FMT_KILOMEGAGIGA) {
			if (cnt > 99999) {
				cntkb = (cnt + 500) / 1000;
				if (cntkb > 9999) {
					cntmb = (cnt + 500000) / 1000000;
					if (cntmb > 9999) {
						cntgb = (cntmb + 500) / 1000;
						fprintf(fp,
							FMT("%4lluG ","%lluG "),
							cntgb);
					}
					else
						fprintf(fp, FMT("%4lluM ","%lluM "), cntmb);
				} else
					fprintf(fp, FMT("%4lluK ","%lluK "), cntkb);
			} else
				fprintf(fp, FMT("%5llu ","%llu "), cnt);
		} else
			fprintf(fp, FMT("%10llu ","%llu "), cnt);
	}

	if (!(format & FMT_NOTARGET))
		fprintf(fp, FMT("%-9s ", "%s "), fw->label);

	fputc(fw->ipfw.fw_invflg & IP_FW_INV_PROTO ? '!' : ' ', fp);
	{
		char *pname = proto_to_name(fw->ipfw.fw_proto);
		if (pname)
			fprintf(fp, FMT("%-5s", "%s "), pname);
		else
			fprintf(fp, FMT("%-5hu", "%hu "), fw->ipfw.fw_proto);
	}

	if (format & FMT_OPTIONS) {
		if (format & FMT_NOTABLE)
			fputs("opt    ", fp);
		fputc((fw->ipfw.fw_invflg & IP_FW_INV_SYN) ? '!' : '-', fp);
		fputc((flags & IP_FW_F_TCPSYN) ? 'y' : '-', fp);
		fputc((fw->ipfw.fw_invflg & IP_FW_INV_FRAG) ? '!' : '-', fp);
		fputc((flags & IP_FW_F_FRAG) ? 'f' : '-', fp);
		fputc((flags & IP_FW_F_PRN) ? 'l' : '-', fp);
		fputc((flags & IP_FW_F_NETLINK) ? 'o' : '-', fp);
		fputc(' ', fp);
	}

	if (format & FMT_TOS) {
		if (format & FMT_NOTABLE)
			fputs("tos ", fp);
		fprintf(fp, "0x%02hX 0x%02hX ",
			(unsigned short) fw->ipfw.fw_tosand,
			(unsigned short) fw->ipfw.fw_tosxor);
	}

	if (format & FMT_VIA) {
		fputc(fw->ipfw.fw_invflg & IP_FW_INV_VIA ? '!' : ' ', fp);
		if (fw->ipfw.fw_flg & IP_FW_F_WILDIF
		    && (fw->ipfw.fw_vianame)[0]) {
			fw->ipfw.fw_vianame[strlen(fw->ipfw.fw_vianame)+1]='\0';
			fw->ipfw.fw_vianame[strlen(fw->ipfw.fw_vianame)]='+';
		}
		fprintf(fp, FMT("%-10.16s ","via %.16s "),
			(fw->ipfw.fw_vianame)[0] ? fw->ipfw.fw_vianame :
				((format & FMT_NUMERIC) ? "*" : "any"));
	}

	if (format & FMT_MARK) {
		if (fw->ipfw.fw_flg & IP_FW_F_MARKABS)
			fprintf(fp, FMT("0x%-10x ","mark 0x%x "),fw->ipfw.fw_mark);
		else if (fw->ipfw.fw_mark == 0)
			fputs(FMT("           ", ""), fp);
		else
			fprintf(fp, FMT("0x%+-10x ","mark 0x%+x "),
				(int)fw->ipfw.fw_mark);
	}

	if (format & FMT_NETLINK) {
		if ((fw->ipfw.fw_flg & IP_FW_F_NETLINK)
		    && (fw->ipfw.fw_outputsize != 0xFFFF))
			fprintf(fp, FMT("%-7hu ","outsize %hu "),
				fw->ipfw.fw_outputsize);
		else
			fputs(FMT("        ", ""), fp);
	}

	if (format & FMT_NOTABLE)
		fputs("  ", fp);

	fputc(fw->ipfw.fw_invflg & IP_FW_INV_SRCIP ? '!' : ' ', fp);
	if (fw->ipfw.fw_smsk.s_addr == 0L && !(format & FMT_NUMERIC))
		fprintf(fp, FMT("%-20s ","%s "), "anywhere");
	else {
		if (format & FMT_NUMERIC)
			sprintf(buf, "%s", addr_to_dotted(&(fw->ipfw.fw_src)));
		else
			sprintf(buf, "%s", addr_to_anyname(&(fw->ipfw.fw_src)));
		strcat(buf, mask_to_dotted(&(fw->ipfw.fw_smsk)));
		fprintf(fp, FMT("%-20s ","%s "), buf);
	}

	fputc(fw->ipfw.fw_invflg & IP_FW_INV_DSTIP ? '!' : ' ', fp);
	if (fw->ipfw.fw_dmsk.s_addr == 0L && !(format & FMT_NUMERIC))
		fprintf(fp, FMT("%-20s","-> %s"), "anywhere");
	else {
		if (format & FMT_NUMERIC)
			sprintf(buf, "%s", addr_to_dotted(&(fw->ipfw.fw_dst)));
		else
			sprintf(buf, "%s", addr_to_anyname(&(fw->ipfw.fw_dst)));
		strcat(buf, mask_to_dotted(&(fw->ipfw.fw_dmsk)));
		fprintf(fp, FMT("%-20s","-> %s"), buf);
	}

	if (format & FMT_NOTABLE)
		fputs("  ", fp);

	if (fw->ipfw.fw_proto != IPPROTO_TCP
	    && fw->ipfw.fw_proto != IPPROTO_UDP
	    && fw->ipfw.fw_proto != IPPROTO_ICMP) {
		fputs("  n/a", fp);
		if (!(format & FMT_NONEWLINE))
			putc('\n', fp);
		return;
	}

	/* ICMP handled specially. */
	if (fw->ipfw.fw_proto == IPPROTO_ICMP
	    && !(fw->ipfw.fw_invflg & IP_FW_INV_SRCPT)
	    && !(fw->ipfw.fw_invflg & IP_FW_INV_DSTPT)
	    && !(format & FMT_NUMERIC)) {
		unsigned int i;
		for (i = 0;
		     i < sizeof(icmp_codes)/sizeof(struct icmp_names);
		     i++) {
			if (icmp_codes[i].type == fw->ipfw.fw_spts[0]
			    && icmp_codes[i].type == fw->ipfw.fw_spts[1]
			    && icmp_codes[i].code_min == fw->ipfw.fw_dpts[0]
			    && icmp_codes[i].code_max == fw->ipfw.fw_dpts[1]) {
				fprintf(fp, "  %s", icmp_codes[i].name);
				if (!(format & FMT_NONEWLINE))
					putc('\n', fp);
				return;
			}
		}
	}

	fputs(fw->ipfw.fw_invflg & IP_FW_INV_SRCPT ? " !" : "  ", fp);
	if (fw->ipfw.fw_spts[0] == 0 && fw->ipfw.fw_spts[1] == 0xFFFF)
		fputs((format & FMT_NUMERIC) ? "*" : "any", fp);
	else if (fw->ipfw.fw_spts[0] == fw->ipfw.fw_spts[1]) {
		print_port(fp, format & FMT_NUMERIC,
			   fw->ipfw.fw_spts[0], fw->ipfw.fw_proto);
	}
	else {
		print_port(fp, format & FMT_NUMERIC,
			   fw->ipfw.fw_spts[0], fw->ipfw.fw_proto);
		fputc(':', fp);
		print_port(fp, format & FMT_NUMERIC,
			   fw->ipfw.fw_spts[1], fw->ipfw.fw_proto);
	}

	fputs(" -> ", fp);

	fputs(fw->ipfw.fw_invflg & IP_FW_INV_DSTPT ? " !" : "  ", fp);
	if (fw->ipfw.fw_dpts[0] == 0 && fw->ipfw.fw_dpts[1] == 0xFFFF)
		fputs((format & FMT_NUMERIC) ? "*" : "any", fp);
	else if (fw->ipfw.fw_dpts[0] == fw->ipfw.fw_dpts[1]) {
		print_port(fp, format & FMT_NUMERIC,
			   fw->ipfw.fw_dpts[0], fw->ipfw.fw_proto);
	}
	else {
		print_port(fp, format & FMT_NUMERIC,
			   fw->ipfw.fw_dpts[0], fw->ipfw.fw_proto);
		fputc(':', fp);
		print_port(fp, format & FMT_NUMERIC,
			   fw->ipfw.fw_dpts[1], fw->ipfw.fw_proto);
	}

	if (strcmp(fw->label, IP_FW_LABEL_REDIRECT) == 0) {
		fputs(FMT(" => ", ""), fp);
		if (fw->ipfw.fw_redirpt == 0)
			fputs((format & FMT_NUMERIC) ? " *" : " any", fp);
		else
			print_port(fp, format & FMT_NUMERIC,
				   fw->ipfw.fw_redirpt, fw->ipfw.fw_proto);
	}

	if (!(format & FMT_NONEWLINE))
		putc('\n', fp);
}

static void
print_masq(FILE *fp, struct masq *ms, int format)
{
	unsigned long minutes, seconds, sec100s;
	unsigned short proto;
	char *service;

	if (format & FMT_HEADER) {
		fputs("prot ", fp);
		fprintf(fp, "%-8s ", "expire");
		if (format & FMT_DELTAS) {
			fprintf(fp, "%10s delta prevd ", "initseq");
		}
		fprintf(fp, "%-20s ", "source");
		fprintf(fp, "%-20s ", "destination");
		fputs("ports\n", fp);
	}

	fprintf(fp, "%-5s", ms->proto);

	sec100s = ((ms->expires % HZ) * 100) / HZ;
	seconds = (ms->expires / HZ) % 60;
	minutes = ms->expires / (60 * HZ);

	fprintf(fp, "%02ld:%02ld.%02ld ", minutes, seconds, sec100s);

	if (format & FMT_DELTAS) {
		fprintf(fp, "%10lu %5hd %5hd ", (unsigned long) ms->initseq,
			ms->delta, ms->pdelta);
	}

	if (format & FMT_NUMERIC) {
		fprintf(fp, "%-20s ", addr_to_dotted(&(ms->src)));
		fprintf(fp, "%-20s ", addr_to_dotted(&(ms->dst)));
	} else {
		fprintf(fp, "%-20s ", addr_to_anyname(&(ms->src)));
		fprintf(fp, "%-20s ", addr_to_anyname(&(ms->dst)));
	}

	if (strcmp(ms->proto, "TCP") == 0) proto = IPPROTO_TCP;
	else if (strcmp(ms->proto, "UDP") == 0) proto = IPPROTO_UDP;
	else proto = 0;

	if ((format & FMT_NUMERIC) || !proto)
		fprintf(fp, "%u (%u) -> %u\n", ms->sport, ms->mport, ms->dport);
	else {
		if ((service = port_to_service(ms->sport, proto)) != NULL)
			fprintf(fp, "%s (%u) -> ", service, ms->mport);
		else
			fprintf(fp, "%u (%u) -> ", ms->sport, ms->mport);
		if ((service = port_to_service(ms->dport, proto)) != NULL)
			fprintf(fp, "%s\n", service);
		else
			fprintf(fp, "%u\n", ms->dport);
	}
}

static int
read_masqinfo(FILE *fp, struct masq *mslist, int nmslist)
{
	int n, nread = 0;
	struct masq *ms;
	char buf[256];
	unsigned long temp[3];

	for (nread = 0; nread < nmslist; nread++) {
		ms = &mslist[nread];
		if ((n = fscanf(fp, " %s %lX:%hX %lX:%hX %hX %lX %hd %hd %lu",
				buf, &temp[0], &ms->sport, &temp[1], &ms->dport,
				&ms->mport, &temp[2], &ms->delta,
				&ms->pdelta, &ms->expires)) == -1)
			return nread;
		else if (n != 10)
			exit_error(VERSION_PROBLEM, "unexpected input data");

		strncpy(ms->proto, buf, sizeof(ms->proto));
		ms->proto[sizeof(ms->proto)-1] = '\0';

		/* we always keep these addresses in network byte order */
		ms->src.s_addr = (__u32) htonl(temp[0]);
		ms->dst.s_addr = (__u32) htonl(temp[1]);

		ms->initseq = (__u32) temp[2];
	}
	return nread;
}

static void
set_option(unsigned int *options, unsigned int option, __u16 *invflg)
{
	if (*options & option)
		exit_error(PARAMETER_PROBLEM, "multiple -%c flags not allowed\n",
			   opt2char(option));
	else *options |= option;

	if (invert) {
		unsigned int i;
		for (i = 0; 1 << i != option; i++);
		if (!inverse_for_options[i])
			exit_error(PARAMETER_PROBLEM, "cannot have ! before -%c\n",
				   opt2char(option));
		*invflg |= inverse_for_options[i];
		invert = FALSE;
	}
}

static void
inaddrcpy(struct in_addr *dst, struct in_addr *src)
{
	/* memcpy(dst, src, sizeof(struct in_addr)); */
	dst->s_addr = src->s_addr;
}

static void *
fw_malloc(size_t size)
{
	void *p;

	if ((p = malloc(size)) == NULL) {
		perror("ipchains: malloc failed");
		exit(1);
	}
	return p;
}

static void *
fw_calloc(size_t count, size_t size)
{
	void *p;

	if ((p = calloc(count, size)) == NULL) {
		perror("ipchains: calloc failed");
		exit(1);
	}
	return p;
}

static void *
fw_realloc(void *ptr, size_t size)
{
	void *p;

	if ((p = realloc(ptr, size)) == NULL) {
		perror("ipchains: realloc failed");
		exit(1);
	}
	return p;
}

static void
exit_error(enum exittype status, char *msg, ...)
{
	va_list args;

	va_start(args, msg);
	fprintf(stderr, "%s: ", program);
	vfprintf(stderr, msg, args);
	va_end(args);
	fprintf(stderr, "\n");
	if (status == PARAMETER_PROBLEM) exit_tryhelp(status);
	else if (status == VERSION_PROBLEM)
		fprintf(stderr, "Perhaps ipchains or your kernel need to be upgraded.\n");
	exit(status);
}

static void
exit_tryhelp(int status)
{
	fprintf(stderr, "See IPChains.pm documentation for more information.\n");
	exit(status);
}

static void
exit_printicmphelp()
{
	unsigned int i;
	printf("%s\n\n"
	       "Valid ICMP Types:",
	       package_version);

	for (i = 0; i < sizeof(icmp_codes)/sizeof(struct icmp_names); i++) {
		if (i && icmp_codes[i].type == icmp_codes[i-1].type) {
			if (icmp_codes[i].code_min == icmp_codes[i-1].code_min
			    && (icmp_codes[i].code_max
				== icmp_codes[i-1].code_max))
				printf(" (%s)", icmp_codes[i].name);
			else
				printf("\n   %s", icmp_codes[i].name);
		}
		else
			printf("\n%s", icmp_codes[i].name);
	}
	printf("\n");
	exit(0);
}

static void
exit_printhelp()
{
	printf("%s\n\n"
"Usage: %s -[ADC] chain rule-specification [options]\n"
"       %s -[RI] chain rulenum rule-specification [options]\n"
"       %s -D chain rulenum [options]\n"
"       %s -[LFZNX] [chain] [options]\n"
"       %s -P chain target [options]\n"
"       %s -M [ -L | -S ] [options]\n"
"       %s -h [icmp] (print this help information, or ICMP list)\n\n",
	       package_version, program, program, program, program, program,
	       program, program);

	printf(
"Commands:\n"
"Either long or short options are allowed.\n"
"  --add     -A chain		Append to chain\n"
"  --delete  -D chain		Delete matching rule from chain\n"
"  --delete  -D chain rulenum\n"
"				Delete rule rulenum (1 = first) from chain\n"
"  --insert  -I chain [rulenum]\n"
"				Insert in chain as rulenum (default 1=first)\n"
"  --replace -R chain rulenum\n"
"				Replace rule rulenum (1 = first) in chain\n"
"  --list    -L [chain]		List the rules in a chain or all chains\n"
"  --flush   -F [chain]		Delete all rules in  chain or all chains\n"
"  --zero    -Z [chain]		Zero counters in chain or all chains\n"
"  --check   -C chain		Test this packet on chain\n"
"  --new     -N chain		Create a new user-defined chain\n"
"  --delete  -X chain		Delete a user-defined chain\n"
"  --policy  -P chain target\n"
"				Change policy on chain to target\n"
"  --masquerade -M -L		List current masqerading connections\n"
"  --masquerade -M -S tcp tcpfin udp\n"
"				Set masquerading timeout values\n\n"

"Options:\n"
"  --bidirectional -b		insert two rules: one with -s & -d reversed\n"
"  --proto	-p [!] proto	protocol: by number or name, eg. `tcp'\n"
"  --source	-s [!] address[/mask] [!] [port[:port]]\n"
"				source specification\n"
"  --source-port [!] [port[:port]]\n"
"				source port specification\n"
"  --destination -d [!] address[/mask] [!] [port[:port]]\n"
"				destination specification\n"
"  --destination-port [!] [port[:port]]\n"
"				destination port specification\n"
"  --icmp-type [!] typename	specify ICMP type\n"
"  --interface	-i [!] name[+]\n"
"				network interface name ([+] for wildcard)\n"
"  --jump	-j target [port]\n"
"				target for rule ([port] for REDIRECT)\n"
"  --mark	-m [+-]mark	number to mark on matching packet\n"
"  --numeric	-n		numeric output of addresses and ports\n"
"  --log		-l		turn on kernel logging for matching packets\n"
"  --output	-o [maxsize]	output matching packet to netlink device\n"
"  --TOS		-t and xor	and/xor masks for TOS field\n"
"  --verbose	-v		verbose mode\n"
"  --exact	-x		expand numbers (display exact values)\n"
"[!] --fragment	-f		match second or further fragments only\n"
"[!] --syn	-y		match TCP packets only when SYN set\n"
"[!] --version	-V		print package version.\n");

	exit(0);
}

static void
generic_opt_check(int command, int options)
{
	int i,j,legal=0;

	/* Check that commands are valid with options.  Complicated by the
	 * fact that if an option is legal with *any* command given, it is
	 * legal overall (ie. -z and -l).
	 */
	for (i = 0; i < NUMBER_OF_OPT; i++) {
		legal = 0; /* -1 => illegal, 1 => legal, 0 => undecided. */

		for (j = 0; j < NUMBER_OF_CMD; j++) {
			if (!(command & (1<<j)))
				continue;

			if (!(options & (1<<i))) {
				if (commands_v_options[j][i] == '+')
					exit_error(PARAMETER_PROBLEM, "You need to supply the `-%c' option for this command\n", optflags[i]);
			}
			else {
				if (commands_v_options[j][i] != 'x')
					legal = 1;
				else if (legal == 0)
					legal = -1;
			}
		}
		if (legal == -1)
			exit_error(PARAMETER_PROBLEM,
				   "Illegal option `-%c' with this command\n",
				   optflags[i]);
	}
}

static char
opt2char(int option)
{
	const char *ptr;
	for (ptr = optflags; option > 1; option >>=1, ptr++);

	return *ptr;
}

static char
cmd2char(int option)
{
	const char *ptr;
	for (ptr = cmdflags; option > 1; option >>=1, ptr++);

	return *ptr;
}

static int
count_tos_bits(unsigned char bitpattern)
{
	int bits;

	for (bits = 0, bitpattern &= 0x0E; bitpattern > 0x00; bitpattern >>= 1)
		bits += bitpattern & 0x01;

	return bits;
}

static void
check_tos(unsigned char tosand, unsigned char tosxor)
{
	unsigned int i;

	/* The LSB Must Be Untouched (RFC 1349). */
	if (!(tosand & 1) || (tosxor & 1))
		exit_error(PARAMETER_PROBLEM, "TOS manipulation cannot alter bit 0 (RFC1349)\n");

	/* Don't create packets with more than 1 TOS bit set, (RFC 1349). */
	/* If it will always create a packet with > 1 TOS bit, it's an
	 * error.  If it MIGHT create a packet with > 1 TOS bit set,
	 * issue a warning to stdout (so the user can filter this out
	 * if they really want this.)
	 */
	if (count_tos_bits((~tosand) & tosxor) > 1)
		exit_error(PARAMETER_PROBLEM, "TOS manipulation cannot set multiple TOS bits "
			   "(RFC1349)\n");

	for (i = 0; i < sizeof(TOS_values)/sizeof(struct TOS_value); i++)
		if (count_tos_bits((TOS_values[i].TOS & tosand) ^ tosxor) > 1)
			printf("Warning: TOS manipulation may set multiple "
			       "TOS bits for %s TOS (0x%02x)\n",
			       TOS_values[i].name, TOS_values[i].TOS);
}

static void
add_command(int *cmd, const int newcmd, const int othercmds)
{
	if (invert)
		exit_error(PARAMETER_PROBLEM, "unexpected ! flag");
	if (*cmd & (~othercmds))
		exit_error(PARAMETER_PROBLEM, "Can't use -%c with -%c\n",
			   cmd2char(newcmd), cmd2char(*cmd & (~othercmds)));
	else *cmd |= newcmd;
}