351 lines
		
	
	
		
			12 KiB
		
	
	
	
		
			C
		
	
	
	
			
		
		
	
	
			351 lines
		
	
	
		
			12 KiB
		
	
	
	
		
			C
		
	
	
	
| /*
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|  * Copyright (c) 1993 Daniel Boulet
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|  * Copyright (c) 1994 Ugen J.S.Antsilevich
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|  *
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|  * Redistribution and use in source forms, with and without modification,
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|  * are permitted provided that this entire comment appears intact.
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|  *
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|  * Redistribution in binary form may occur without any restrictions.
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|  * Obviously, it would be nice if you gave credit where credit is due
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|  * but requiring it would be too onerous.
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|  *
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|  * This software is provided ``AS IS'' without any warranties of any kind.
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|  *
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|  * $FreeBSD: src/sys/netinet/ip_fw.h,v 1.66 2002/05/09 10:34:57 luigi Exp $
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|  */
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| 
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| #ifndef _IP_FW_H
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| #define _IP_FW_H
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| 
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| #include <sys/queue.h>
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| 
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| /*
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|  * This union structure identifies an interface, either explicitly
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|  * by name or implicitly by IP address. The flags IP_FW_F_IIFNAME
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|  * and IP_FW_F_OIFNAME say how to interpret this structure. An
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|  * interface unit number of -1 matches any unit number, while an
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|  * IP address of 0.0.0.0 indicates matches any interface.
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|  *
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|  * The receive and transmit interfaces are only compared against the
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|  * the packet if the corresponding bit (IP_FW_F_IIFACE or IP_FW_F_OIFACE)
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|  * is set. Note some packets lack a receive or transmit interface
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|  * (in which case the missing "interface" never matches).
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|  */
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| 
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| union ip_fw_if {
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| 	struct in_addr	fu_via_ip;	/* Specified by IP address */
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| 	struct {			/* Specified by interface name */
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| #define FW_IFNLEN	10		/* need room ! was IFNAMSIZ */
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| 		char	name[FW_IFNLEN];
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| 		short	unit;		/* -1 means match any unit */
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| 	} fu_via_if;
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| };
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| 
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| /*
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|  * Format of an IP firewall descriptor
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|  *
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|  * fw_src, fw_dst, fw_smsk, fw_dmsk are always stored in network byte order.
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|  * fw_flg and fw_n*p are stored in host byte order (of course).
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|  * Port numbers are stored in HOST byte order.
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|  */
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| 
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| /*
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|  * To match MAC headers:
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|  *     12 bytes at fw_mac_hdr contain the dst-src MAC address after masking.
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|  *     12 bytes at fw_mac_mask contain the mask to apply to dst-src
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|  *     2 bytes at fw_mac_type contain the mac type after mask (in net format)
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|  *     2 bytes at fw_mac_type_mask contain the mac type mask
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|  *         If IP_FW_F_SRNG, the two contain the low-high of a range of types.
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|  *     IP_FW_F_DRNG is used to indicare we want to match a vlan.
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|  */
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| #define	fw_mac_hdr		fw_src
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| #define	fw_mac_mask		fw_uar
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| #define	fw_mac_type		fw_iplen
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| #define	fw_mac_mask_type	fw_ipid
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| 
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| struct ip_fw {
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| 	LIST_ENTRY(ip_fw) next;		/* bidirectional list of rules */
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| 	u_int		fw_flg;		/* Operational Flags word */
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| 	u_int64_t	fw_pcnt;	/* Packet counters */
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| 	u_int64_t	fw_bcnt;	/* Byte counters */
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| 
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| 	struct in_addr	fw_src;		/* Source IP address */
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| 	struct in_addr	fw_dst;		/* Destination IP address */
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| 	struct in_addr	fw_smsk;	/* Mask for source IP address */
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| 	struct in_addr	fw_dmsk;	/* Mask for destination address */
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| 	u_short		fw_number;	/* Rule number */
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| 	u_char		fw_prot;	/* IP protocol */
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| #if 1
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| 	u_char		fw_nports;	/* # of src/dst port in array */
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| #define	IP_FW_GETNSRCP(rule)		((rule)->fw_nports & 0x0f)
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| #define	IP_FW_SETNSRCP(rule, n)		do {				\
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| 					    (rule)->fw_nports &= ~0x0f;	\
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| 					    (rule)->fw_nports |= (n);	\
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| 					} while (0)
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| #define	IP_FW_GETNDSTP(rule)		((rule)->fw_nports >> 4)
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| #define	IP_FW_SETNDSTP(rule, n)		do {				  \
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| 					    (rule)->fw_nports &= ~0xf0;	  \
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| 					    (rule)->fw_nports |= (n) << 4;\
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| 					} while (0)
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| #define	IP_FW_HAVEPORTS(rule)		((rule)->fw_nports != 0)
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| #else
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| 	u_char		__pad[1];
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| 	u_int		_nsrcp;
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| 	u_int		_ndstp;
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| #define	IP_FW_GETNSRCP(rule)		(rule)->_nsrcp
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| #define	IP_FW_SETNSRCP(rule,n)		(rule)->_nsrcp = n
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| #define	IP_FW_GETNDSTP(rule)		(rule)->_ndstp
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| #define	IP_FW_SETNDSTP(rule,n)		(rule)->_ndstp = n
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| #define	IP_FW_HAVEPORTS(rule)		((rule)->_ndstp + (rule)->_nsrcp != 0)
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| #endif
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| #define	IP_FW_MAX_PORTS	10		/* A reasonable maximum */
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|     union {
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| 	u_short		fw_pts[IP_FW_MAX_PORTS]; /* port numbers to match */
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| #define	IP_FW_ICMPTYPES_MAX	128
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| #define	IP_FW_ICMPTYPES_DIM	(IP_FW_ICMPTYPES_MAX / (sizeof(unsigned) * 8))
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| 	unsigned	fw_icmptypes[IP_FW_ICMPTYPES_DIM]; /*ICMP types bitmap*/
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|     } fw_uar;
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| 
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| 	u_int		fw_ipflg;	/* IP flags word */
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| 	u_short		fw_iplen;	/* IP length */
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| 	u_short		fw_ipid;	/* Identification */
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| 	u_char		fw_ipopt;	/* IP options set */
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| 	u_char		fw_ipnopt;	/* IP options unset */
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| 	u_char		fw_iptos;	/* IP type of service set */
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| 	u_char		fw_ipntos;	/* IP type of service unset */
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| 	u_char		fw_ipttl;	/* IP time to live */
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| 	u_int		fw_ipver:4;	/* IP version */
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| 	u_char		fw_tcpopt;	/* TCP options set */
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| 	u_char		fw_tcpnopt;	/* TCP options unset */
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| 	u_char		fw_tcpf;	/* TCP flags set */
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| 	u_char		fw_tcpnf;	/* TCP flags unset */
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| 	u_short		fw_tcpwin;	/* TCP window size */
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| 	u_int32_t	fw_tcpseq;	/* TCP sequence */
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| 	u_int32_t	fw_tcpack;	/* TCP acknowledgement */
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| 	long		timestamp;	/* timestamp (tv_sec) of last match */
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| 	union ip_fw_if	fw_in_if;	/* Incoming interfaces */
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| 	union ip_fw_if	fw_out_if;	/* Outgoing interfaces */
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|     union {
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| 	u_short		fu_divert_port;	/* Divert/tee port (options IPDIVERT) */
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| 	u_short		fu_pipe_nr;	/* queue number (option DUMMYNET) */
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| 	u_short		fu_skipto_rule;	/* SKIPTO command rule number */
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| 	u_short		fu_reject_code;	/* REJECT response code */
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| 	struct sockaddr_in fu_fwd_ip;
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|     } fw_un;
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| 	void		*pipe_ptr;	/* flow_set ptr for dummynet pipe */
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| 	void		*next_rule_ptr;	/* next rule in case of match */
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| 	uid_t		fw_uid;		/* uid to match */
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| 	gid_t		fw_gid;		/* gid to match */
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| 	int		fw_logamount;	/* amount to log */
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| 	u_int64_t	fw_loghighest;	/* highest number packet to log */
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| 
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| 	long		dont_match_prob; /* 0x7fffffff means 1.0, always fail */
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| 	u_char		dyn_type;	/* type for dynamic rule */
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| 
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| #define	DYN_KEEP_STATE	0	/* type for keep-state rules	*/
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| #define	DYN_LIMIT	1	/* type for limit connection rules */
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| #define	DYN_LIMIT_PARENT 2	/* parent entry for limit connection rules */
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| 
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| 	/* following two fields are used to limit number of connections
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| 	 * basing on either src, srcport, dst, dstport.
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| 	 */
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| 	u_char		limit_mask;	/* mask type for limit rule, can
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| 					 * have many.
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| 					 */
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| #define	DYN_SRC_ADDR	0x1
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| #define	DYN_SRC_PORT	0x2
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| #define	DYN_DST_ADDR	0x4
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| #define	DYN_DST_PORT	0x8
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| 
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| 	u_short		conn_limit;	/* # of connections for limit rule */
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| };
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| 
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| #define	fw_divert_port	fw_un.fu_divert_port
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| #define	fw_skipto_rule	fw_un.fu_skipto_rule
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| #define	fw_reject_code	fw_un.fu_reject_code
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| #define	fw_pipe_nr	fw_un.fu_pipe_nr
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| #define	fw_fwd_ip	fw_un.fu_fwd_ip
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| 
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| /*
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|  *
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|  *   rule_ptr  -------------+
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|  *                          V
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|  *     [ next.le_next ]---->[ next.le_next ]---- [ next.le_next ]--->
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|  *     [ next.le_prev ]<----[ next.le_prev ]<----[ next.le_prev ]<---
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|  *     [ <ip_fw> body ]     [ <ip_fw> body ]     [ <ip_fw> body ]
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|  *
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|  */
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| 
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| /*
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|  * Flow mask/flow id for each queue.
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|  */
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| struct ipfw_flow_id {
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| 	u_int32_t	dst_ip;
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| 	u_int32_t	src_ip;
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| 	u_int16_t	dst_port;
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| 	u_int16_t	src_port;
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| 	u_int8_t	proto;
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| 	u_int8_t	flags;	/* protocol-specific flags */
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| };
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| 
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| /*
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|  * dynamic ipfw rule
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|  */
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| struct ipfw_dyn_rule {
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| 	struct ipfw_dyn_rule *next;
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| 	struct ipfw_flow_id id;		/* (masked) flow id */
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| 	struct ip_fw	*rule;		/* pointer to rule */
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| 	struct ipfw_dyn_rule *parent;	/* pointer to parent rule */
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| 	u_int32_t	expire;		/* expire time */
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| 	u_int64_t	pcnt;		/* packet match counters */
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| 	u_int64_t	bcnt;		/* byte match counters */
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| 	u_int32_t	bucket;		/* which bucket in hash table */
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| 	u_int32_t	state;		/* state of this rule (typically a
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| 					 * combination of TCP flags)
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| 					 */
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| 	u_int16_t	dyn_type;	/* rule type */
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| 	u_int16_t	count;		/* refcount */
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| };
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| 
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| /*
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|  * Values for "flags" field .
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|  */
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| #define	IP_FW_F_COMMAND	0x000000ff	/* Mask for type of chain entry: */
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| #define	IP_FW_F_DENY	0x00000000	/* This is a deny rule */
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| #define	IP_FW_F_REJECT	0x00000001	/* Deny and send a response packet */
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| #define	IP_FW_F_ACCEPT	0x00000002	/* This is an accept rule */
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| #define	IP_FW_F_COUNT	0x00000003	/* This is a count rule */
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| #define	IP_FW_F_DIVERT	0x00000004	/* This is a divert rule */
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| #define	IP_FW_F_TEE	0x00000005	/* This is a tee rule */
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| #define	IP_FW_F_SKIPTO	0x00000006	/* This is a skipto rule */
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| #define	IP_FW_F_FWD	0x00000007	/* This is a "change forwarding
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| 					 * address" rule
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| 					 */
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| #define	IP_FW_F_PIPE	0x00000008	/* This is a dummynet rule */
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| #define	IP_FW_F_QUEUE	0x00000009	/* This is a dummynet queue */
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| 
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| #define	IP_FW_F_IN	0x00000100	/* Check inbound packets */
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| #define	IP_FW_F_OUT	0x00000200	/* Check outbound packets */
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| #define	IP_FW_F_IIFACE	0x00000400	/* Apply inbound interface test */
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| #define	IP_FW_F_OIFACE	0x00000800	/* Apply outbound interface test */
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| #define	IP_FW_F_PRN	0x00001000	/* Print if this rule matches */
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| #define	IP_FW_F_SRNG	0x00002000	/* The first two src ports are a min
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| 					 * and max range (stored in host byte
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| 					 * order).
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| 					 */
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| #define	IP_FW_F_DRNG	0x00004000	/* The first two dst ports are a min
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| 					 * and max range (stored in host byte
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| 					 * order).
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| 					 */
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| #define	IP_FW_F_FRAG	0x00008000	/* Fragment */
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| #define	IP_FW_F_IIFNAME	0x00010000	/* In interface by name/unit (not IP) */
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| #define	IP_FW_F_OIFNAME	0x00020000	/* Out interface by name/unit (not IP)*/
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| #define	IP_FW_F_INVSRC	0x00040000	/* Invert sense of src check */
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| #define	IP_FW_F_INVDST	0x00080000	/* Invert sense of dst check */
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| #define	IP_FW_F_ICMPBIT	0x00100000	/* ICMP type bitmap is valid */
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| #define	IP_FW_F_UID	0x00200000	/* filter by uid */
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| #define	IP_FW_F_GID	0x00400000	/* filter by gid */
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| #define	IP_FW_F_RND_MATCH 0x00800000	/* probabilistic rule match */
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| #define	IP_FW_F_SMSK	0x01000000	/* src-port + mask */
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| #define	IP_FW_F_DMSK	0x02000000	/* dst-port + mask */
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| #define	IP_FW_BRIDGED	0x04000000	/* only match bridged packets */
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| #define	IP_FW_F_KEEP_S	0x08000000	/* keep state */
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| #define	IP_FW_F_CHECK_S	0x10000000	/* check state */
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| #define	IP_FW_F_SME	0x20000000	/* source = me */
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| #define	IP_FW_F_DME	0x40000000	/* destination = me */
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| #define	IP_FW_F_MAC	0x80000000	/* match MAC header */
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| 
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| #define	IP_FW_F_MASK	0xFFFFFFFF	/* All possible flag bits mask */
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| 
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| /*
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|  * Flags for the 'fw_ipflg' field, for comparing values
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|  * of ip and its protocols.
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|  */
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| #define	IP_FW_IF_TCPOPT	0x00000001	/* tcp options */
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| #define	IP_FW_IF_TCPFLG	0x00000002	/* tcp flags */
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| #define	IP_FW_IF_TCPSEQ	0x00000004	/* tcp sequence number */
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| #define	IP_FW_IF_TCPACK	0x00000008	/* tcp acknowledgement number */
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| #define	IP_FW_IF_TCPWIN	0x00000010	/* tcp window size */
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| #define	IP_FW_IF_TCPEST	0x00000020	/* established TCP connection */
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| #define	IP_FW_IF_TCPMSK	0x0000003f	/* mask of all tcp values */
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| #define	IP_FW_IF_IPOPT	0x00000100	/* ip options */
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| #define	IP_FW_IF_IPLEN	0x00000200	/* ip length */
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| #define	IP_FW_IF_IPID	0x00000400	/* ip identification */
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| #define	IP_FW_IF_IPTOS	0x00000800	/* ip type of service */
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| #define	IP_FW_IF_IPTTL	0x00001000	/* ip time to live */
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| #define	IP_FW_IF_IPVER	0x00002000	/* ip version */
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| #define	IP_FW_IF_IPPRE	0x00004000	/* ip precedence */
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| #define	IP_FW_IF_IPMSK	0x00007f00	/* mask of all ip values */
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| #define	IP_FW_IF_MSK	0x0000ffff	/* All possible bits mask */
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| 
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| /*
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|  * For backwards compatibility with rules specifying "via iface" but
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|  * not restricted to only "in" or "out" packets, we define this combination
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|  * of bits to represent this configuration.
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|  */
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| 
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| #define	IF_FW_F_VIAHACK	(IP_FW_F_IN|IP_FW_F_OUT|IP_FW_F_IIFACE|IP_FW_F_OIFACE)
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| 
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| /*
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|  * Definitions for REJECT response codes.
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|  * Values less than 256 correspond to ICMP unreachable codes.
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|  */
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| #define	IP_FW_REJECT_RST	0x0100	/* TCP packets: send RST */
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| 
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| /*
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|  * Definitions for IP option names.
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|  */
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| #define	IP_FW_IPOPT_LSRR	0x01
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| #define	IP_FW_IPOPT_SSRR	0x02
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| #define	IP_FW_IPOPT_RR		0x04
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| #define	IP_FW_IPOPT_TS		0x08
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| 
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| /*
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|  * Definitions for TCP option names.
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|  */
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| #define	IP_FW_TCPOPT_MSS	0x01
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| #define	IP_FW_TCPOPT_WINDOW	0x02
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| #define	IP_FW_TCPOPT_SACK	0x04
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| #define	IP_FW_TCPOPT_TS		0x08
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| #define	IP_FW_TCPOPT_CC		0x10
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| 
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| /*
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|  * Definitions for TCP flags.
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|  */
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| #define	IP_FW_TCPF_FIN		TH_FIN
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| #define	IP_FW_TCPF_SYN		TH_SYN
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| #define	IP_FW_TCPF_RST		TH_RST
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| #define	IP_FW_TCPF_PSH		TH_PUSH
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| #define	IP_FW_TCPF_ACK		TH_ACK
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| #define	IP_FW_TCPF_URG		TH_URG
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| 
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| /*
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|  * Main firewall chains definitions and global var's definitions.
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|  */
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| #ifdef _KERNEL
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| 
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| #define	IP_FW_PORT_DYNT_FLAG	0x10000
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| #define	IP_FW_PORT_TEE_FLAG	0x20000
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| #define	IP_FW_PORT_DENY_FLAG	0x40000
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| 
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| /*
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|  * Function definitions.
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|  */
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| void ip_fw_init(void);
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| 
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| /* Firewall hooks */
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| struct ip;
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| struct sockopt;
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| typedef int ip_fw_chk_t (struct mbuf **m, struct ifnet *oif,
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|     u_int16_t *cookie, struct ip_fw **rule, struct sockaddr_in **next_hop);
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| typedef int ip_fw_ctl_t (struct sockopt *);
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| extern ip_fw_chk_t *ip_fw_chk_ptr;
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| extern ip_fw_ctl_t *ip_fw_ctl_ptr;
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| extern int fw_one_pass;
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| extern int fw_enable;
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| extern struct ipfw_flow_id last_pkt;
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| #define	IPFW_LOADED	(ip_fw_chk_ptr != NULL)
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| #endif /* _KERNEL */
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| 
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| #endif /* _IP_FW_H */
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