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1633 |
jcastillo |
/*
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* IP firewalling code. This is taken from 4.4BSD. Please note the
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* copyright message below. As per the GPL it must be maintained
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* and the licenses thus do not conflict. While this port is subject
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* to the GPL I also place my modifications under the original
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* license in recognition of the original copyright.
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*
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* Ported from BSD to Linux,
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* Alan Cox 22/Nov/1994.
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* Merged and included the FreeBSD-Current changes at Ugen's request
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* (but hey it's a lot cleaner now). Ugen would prefer in some ways
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* we waited for his final product but since Linux 1.2.0 is about to
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* appear it's not practical - Read: It works, it's not clean but please
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* don't consider it to be his standard of finished work.
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* Alan.
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*
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* Fixes:
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* Pauline Middelink : Added masquerading.
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* Jos Vos : Separate input and output firewall
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* chains, new "insert" and "append"
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* commands to replace "add" commands,
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* add ICMP header to struct ip_fwpkt.
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* Jos Vos : Add support for matching device names.
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* Willy Konynenberg : Add transparent proxying support.
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* Jos Vos : Add options for input/output accounting.
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*
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* All the real work was done by .....
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*/
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/*
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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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/*
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* Format of an IP firewall descriptor
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*
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* src, dst, src_mask, dst_mask are always stored in network byte order.
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* flags and num_*_ports 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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#ifndef _IP_FW_H
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#define _IP_FW_H
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#include <linux/icmp.h>
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#include <linux/in.h>
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#include <linux/ip.h>
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#include <linux/tcp.h>
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#include <linux/udp.h>
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#include <linux/config.h>
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#include <linux/if.h>
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struct ip_fw
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{
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struct ip_fw *fw_next; /* Next firewall on chain */
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struct in_addr fw_src, fw_dst; /* Source and destination IP addr */
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struct in_addr fw_smsk, fw_dmsk; /* Mask for src and dest IP addr */
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struct in_addr fw_via; /* IP address of interface "via" */
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struct device *fw_viadev; /* device of interface "via" */
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unsigned short fw_flg; /* Flags word */
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unsigned short fw_nsp, fw_ndp; /* N'of src ports and # of dst ports */
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/* in ports array (dst ports follow */
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/* src ports; max of 10 ports in all; */
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/* count of 0 means match all ports) */
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#define IP_FW_MAX_PORTS 10 /* A reasonable maximum */
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unsigned short fw_pts[IP_FW_MAX_PORTS]; /* Array of port numbers to match */
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unsigned long fw_pcnt,fw_bcnt; /* Packet and byte counters */
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unsigned char fw_tosand, fw_tosxor; /* Revised packet priority */
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char fw_vianame[IFNAMSIZ]; /* name of interface "via" */
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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_ALL 0x0000 /* This is a universal packet firewall*/
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#define IP_FW_F_TCP 0x0001 /* This is a TCP packet firewall */
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#define IP_FW_F_UDP 0x0002 /* This is a UDP packet firewall */
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#define IP_FW_F_ICMP 0x0003 /* This is a ICMP packet firewall */
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#define IP_FW_F_KIND 0x0003 /* Mask to isolate firewall kind */
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#define IP_FW_F_ACCEPT 0x0004 /* This is an accept firewall (as *
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* opposed to a deny firewall)*
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* */
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#define IP_FW_F_SRNG 0x0008 /* 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 0x0010 /* 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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* (ports[0] <= port <= ports[1]) *
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* */
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#define IP_FW_F_PRN 0x0020 /* In verbose mode print this firewall*/
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#define IP_FW_F_BIDIR 0x0040 /* For bidirectional firewalls */
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#define IP_FW_F_TCPSYN 0x0080 /* For tcp packets-check SYN only */
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#define IP_FW_F_ICMPRPL 0x0100 /* Send back icmp unreachable packet */
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#define IP_FW_F_MASQ 0x0200 /* Masquerading */
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#define IP_FW_F_TCPACK 0x0400 /* For tcp-packets match if ACK is set*/
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#define IP_FW_F_REDIR 0x0800 /* Redirect to local port fw_pts[n] */
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#define IP_FW_F_ACCTIN 0x1000 /* Account incoming packets only. */
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#define IP_FW_F_ACCTOUT 0x2000 /* Account outgoing packets only. */
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#define IP_FW_F_MASK 0x3FFF /* All possible flag bits mask */
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/*
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* New IP firewall options for [gs]etsockopt at the RAW IP level.
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* Unlike BSD Linux inherits IP options so you don't have to use
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* a raw socket for this. Instead we check rights in the calls.
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*/
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#define IP_FW_BASE_CTL 64 /* base for firewall socket options */
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#define IP_FW_COMMAND 0x00FF /* mask for command without chain */
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#define IP_FW_TYPE 0x0300 /* mask for type (chain) */
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#define IP_FW_SHIFT 8 /* shift count for type (chain) */
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#define IP_FW_FWD 0
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#define IP_FW_IN 1
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#define IP_FW_OUT 2
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#define IP_FW_ACCT 3
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#define IP_FW_CHAINS 4 /* total number of ip_fw chains */
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#ifdef CONFIG_IP_MASQUERADE_IPAUTOFW
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#define IP_FW_AUTOFW 5
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#endif
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#ifdef CONFIG_IP_MASQUERADE_IPPORTFW
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#define IP_FW_PORTFW 6
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#endif
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#define IP_FW_INSERT (IP_FW_BASE_CTL)
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#define IP_FW_APPEND (IP_FW_BASE_CTL+1)
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#define IP_FW_DELETE (IP_FW_BASE_CTL+2)
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#define IP_FW_FLUSH (IP_FW_BASE_CTL+3)
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#define IP_FW_ZERO (IP_FW_BASE_CTL+4)
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#define IP_FW_POLICY (IP_FW_BASE_CTL+5)
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#define IP_FW_CHECK (IP_FW_BASE_CTL+6)
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#define IP_FW_MASQ_TIMEOUTS (IP_FW_BASE_CTL+7)
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#define IP_FW_INSERT_FWD (IP_FW_INSERT | (IP_FW_FWD << IP_FW_SHIFT))
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#define IP_FW_APPEND_FWD (IP_FW_APPEND | (IP_FW_FWD << IP_FW_SHIFT))
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#define IP_FW_DELETE_FWD (IP_FW_DELETE | (IP_FW_FWD << IP_FW_SHIFT))
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#define IP_FW_FLUSH_FWD (IP_FW_FLUSH | (IP_FW_FWD << IP_FW_SHIFT))
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#define IP_FW_ZERO_FWD (IP_FW_ZERO | (IP_FW_FWD << IP_FW_SHIFT))
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#define IP_FW_POLICY_FWD (IP_FW_POLICY | (IP_FW_FWD << IP_FW_SHIFT))
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#define IP_FW_CHECK_FWD (IP_FW_CHECK | (IP_FW_FWD << IP_FW_SHIFT))
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#define IP_FW_INSERT_IN (IP_FW_INSERT | (IP_FW_IN << IP_FW_SHIFT))
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#define IP_FW_APPEND_IN (IP_FW_APPEND | (IP_FW_IN << IP_FW_SHIFT))
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#define IP_FW_DELETE_IN (IP_FW_DELETE | (IP_FW_IN << IP_FW_SHIFT))
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#define IP_FW_FLUSH_IN (IP_FW_FLUSH | (IP_FW_IN << IP_FW_SHIFT))
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#define IP_FW_ZERO_IN (IP_FW_ZERO | (IP_FW_IN << IP_FW_SHIFT))
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#define IP_FW_POLICY_IN (IP_FW_POLICY | (IP_FW_IN << IP_FW_SHIFT))
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#define IP_FW_CHECK_IN (IP_FW_CHECK | (IP_FW_IN << IP_FW_SHIFT))
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#define IP_FW_INSERT_OUT (IP_FW_INSERT | (IP_FW_OUT << IP_FW_SHIFT))
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#define IP_FW_APPEND_OUT (IP_FW_APPEND | (IP_FW_OUT << IP_FW_SHIFT))
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#define IP_FW_DELETE_OUT (IP_FW_DELETE | (IP_FW_OUT << IP_FW_SHIFT))
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#define IP_FW_FLUSH_OUT (IP_FW_FLUSH | (IP_FW_OUT << IP_FW_SHIFT))
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#define IP_FW_ZERO_OUT (IP_FW_ZERO | (IP_FW_OUT << IP_FW_SHIFT))
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#define IP_FW_POLICY_OUT (IP_FW_POLICY | (IP_FW_OUT << IP_FW_SHIFT))
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#define IP_FW_CHECK_OUT (IP_FW_CHECK | (IP_FW_OUT << IP_FW_SHIFT))
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#define IP_ACCT_INSERT (IP_FW_INSERT | (IP_FW_ACCT << IP_FW_SHIFT))
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#define IP_ACCT_APPEND (IP_FW_APPEND | (IP_FW_ACCT << IP_FW_SHIFT))
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#define IP_ACCT_DELETE (IP_FW_DELETE | (IP_FW_ACCT << IP_FW_SHIFT))
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#define IP_ACCT_FLUSH (IP_FW_FLUSH | (IP_FW_ACCT << IP_FW_SHIFT))
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#define IP_ACCT_ZERO (IP_FW_ZERO | (IP_FW_ACCT << IP_FW_SHIFT))
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#ifdef CONFIG_IP_MASQUERADE_IPAUTOFW
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#define IP_AUTOFW_ADD (IP_FW_APPEND | (IP_FW_AUTOFW << IP_FW_SHIFT))
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#define IP_AUTOFW_DEL (IP_FW_DELETE | (IP_FW_AUTOFW << IP_FW_SHIFT))
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#define IP_AUTOFW_FLUSH (IP_FW_FLUSH | (IP_FW_AUTOFW << IP_FW_SHIFT))
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#endif /* CONFIG_IP_MASQUERADE_IPAUTOFW */
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#ifdef CONFIG_IP_MASQUERADE_IPPORTFW
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#define IP_PORTFW_ADD (IP_FW_APPEND | (IP_FW_PORTFW << IP_FW_SHIFT))
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#define IP_PORTFW_DEL (IP_FW_DELETE | (IP_FW_PORTFW << IP_FW_SHIFT))
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#define IP_PORTFW_FLUSH (IP_FW_FLUSH | (IP_FW_PORTFW << IP_FW_SHIFT))
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#endif /* CONFIG_IP_MASQUERADE_IPPORTFW */
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struct ip_fwpkt
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{
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struct iphdr fwp_iph; /* IP header */
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union {
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struct tcphdr fwp_tcph; /* TCP header or */
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struct udphdr fwp_udph; /* UDP header */
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struct icmphdr fwp_icmph; /* ICMP header */
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} fwp_protoh;
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struct in_addr fwp_via; /* interface address */
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char fwp_vianame[IFNAMSIZ]; /* interface name */
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};
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/*
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* timeouts for ip masquerading
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*/
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struct ip_fw_masq;
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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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/* Modes used in the ip_fw_chk() routine. */
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#define IP_FW_MODE_FW 0x00 /* kernel firewall check */
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#define IP_FW_MODE_ACCT_IN 0x01 /* accounting (incoming) */
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#define IP_FW_MODE_ACCT_OUT 0x02 /* accounting (outgoing) */
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#define IP_FW_MODE_CHK 0x04 /* check requested by user */
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#ifdef CONFIG_IP_FIREWALL
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extern struct ip_fw *ip_fw_in_chain;
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extern struct ip_fw *ip_fw_out_chain;
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extern struct ip_fw *ip_fw_fwd_chain;
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extern int ip_fw_in_policy;
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extern int ip_fw_out_policy;
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extern int ip_fw_fwd_policy;
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extern int ip_fw_ctl(int, void *, int);
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#endif
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#ifdef CONFIG_IP_MASQUERADE_IPAUTOFW
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extern int ip_autofw_ctl(int, void *, int);
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#endif
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#ifdef CONFIG_IP_MASQUERADE_IPPORTFW
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extern int ip_portfw_ctl(int, void *, int);
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#endif
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#ifdef CONFIG_IP_ACCT
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extern struct ip_fw *ip_acct_chain;
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extern int ip_acct_ctl(int, void *, int);
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#endif
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extern int ip_fw_chk(struct iphdr *, struct device *, __u16 *, struct ip_fw *, int, int);
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extern void ip_fw_init(void);
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#endif /* KERNEL */
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#ifdef CONFIG_IP_MASQUERADE_IPAUTOFW
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#define IP_FWD_RANGE 1
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#define IP_FWD_PORT 2
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#define IP_FWD_DIRECT 3
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#define IP_AUTOFW_ACTIVE 1
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#define IP_AUTOFW_USETIME 2
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#define IP_AUTOFW_SECURE 4
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struct ip_autofw {
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struct ip_autofw * next;
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__u16 type;
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__u16 low;
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__u16 hidden;
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__u16 high;
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__u16 visible;
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__u16 protocol;
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__u32 lastcontact;
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__u32 where;
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__u16 ctlproto;
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__u16 ctlport;
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__u16 flags;
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struct timer_list timer;
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};
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#endif /* CONFIG_IP_MASQUERADE_IPAUTOFW */
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#ifdef CONFIG_IP_MASQUERADE_IPPORTFW
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#define IP_PORTFW_PORT_MIN 1
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#define IP_PORTFW_PORT_MAX 60999
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| 274 |
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struct ip_portfw {
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struct ip_portfw *next;
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__u32 laddr, raddr;
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__u16 lport, rport;
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};
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struct ip_portfw_edits {
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__u16 protocol; /* Which protocol are we talking? */
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__u32 laddr, raddr; /* Remote address */
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__u16 lport, rport; /* Local and remote port */
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__u16 dummy; /* Make up to multiple of 4 */
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};
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#endif /* CONFIG_IP_MASQUERADE_IPPORTFW */
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#endif /* _IP_FW_H */
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