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#ifndef _IPFWADM_CORE_H
#define _IPFWADM_CORE_H
/* Minor modifications to fit on compatibility framework:
   Rusty.Russell@rustcorp.com.au
*/


/*
 *      IP firewalling code. This is taken from 4.4BSD. Please note the
 *      copyright message below. As per the GPL it must be maintained
 *      and the licenses thus do not conflict. While this port is subject
 *      to the GPL I also place my modifications under the original
 *      license in recognition of the original copyright.
 *
 *      Ported from BSD to Linux,
 *              Alan Cox 22/Nov/1994.
 *      Merged and included the FreeBSD-Current changes at Ugen's request
 *      (but hey it's a lot cleaner now). Ugen would prefer in some ways
 *      we waited for his final product but since Linux 1.2.0 is about to
 *      appear it's not practical - Read: It works, it's not clean but please
 *      don't consider it to be his standard of finished work.
 *              Alan.
 *
 * Fixes:
 *      Pauline Middelink       :       Added masquerading.
 *      Jos Vos                 :       Separate input  and output firewall
 *                                      chains, new "insert" and "append"
 *                                      commands to replace "add" commands,
 *                                      add ICMP header to struct ip_fwpkt.
 *      Jos Vos                 :       Add support for matching device names.
 *      Willy Konynenberg       :       Add transparent proxying support.
 *      Jos Vos                 :       Add options for input/output accounting.
 *
 *      All the real work was done by .....
 */


/*
 * Copyright (c) 1993 Daniel Boulet
 * Copyright (c) 1994 Ugen J.S.Antsilevich
 *
 * Redistribution and use in source forms, with and without modification,
 * are permitted provided that this entire comment appears intact.
 *
 * Redistribution in binary form may occur without any restrictions.
 * Obviously, it would be nice if you gave credit where credit is due
 * but requiring it would be too onerous.
 *
 * This software is provided ``AS IS'' without any warranties of any kind.
 */


/*
 *      Format of an IP firewall descriptor
 *
 *      src, dst, src_mask, dst_mask are always stored in network byte order.
 *      flags and num_*_ports are stored in host byte order (of course).
 *      Port numbers are stored in HOST byte order.
 */


#ifdef __KERNEL__
#include <linux/icmp.h>
#include <linux/in.h>
#include <linux/ip.h>
#include <linux/tcp.h>
#include <linux/udp.h>
#endif

struct ip_fw
{
        struct ip_fw  *fw_next;                 /* Next firewall on chain */
        struct in_addr fw_src, fw_dst;          /* Source and destination IP addr */
        struct in_addr fw_smsk, fw_dmsk;        /* Mask for src and dest IP addr */
        struct in_addr fw_via;                  /* IP address of interface "via" */
        struct net_device *fw_viadev;           /* device of interface "via" */
        __u16   fw_flg;                         /* Flags word */
        __u16   fw_nsp, fw_ndp;                 /* N'of src ports and # of dst ports */
                                                /* in ports array (dst ports follow */
                                                /* src ports; max of 10 ports in all; */
                                                /* count of 0 means match all ports) */
#define IP_FW_MAX_PORTS 10                      /* A reasonable maximum */
        __u16   fw_pts[IP_FW_MAX_PORTS];        /* Array of port numbers to match */
        unsigned long  fw_pcnt,fw_bcnt;         /* Packet and byte counters */
        __u8    fw_tosand, fw_tosxor;           /* Revised packet priority */
        char           fw_vianame[IFNAMSIZ];    /* name of interface "via" */
};

/*
 *      Values for "flags" field .
 */


#define IP_FW_F_ALL     0x0000  /* This is a universal packet firewall*/
#define IP_FW_F_TCP     0x0001  /* This is a TCP packet firewall      */
#define IP_FW_F_UDP     0x0002  /* This is a UDP packet firewall      */
#define IP_FW_F_ICMP    0x0003  /* This is a ICMP packet firewall     */
#define IP_FW_F_KIND    0x0003  /* Mask to isolate firewall kind      */
#define IP_FW_F_ACCEPT  0x0004  /* This is an accept firewall (as     *
                                 *         opposed to a deny firewall)*
                                 *                                    */
#define IP_FW_F_SRNG    0x0008  /* The first two src ports are a min  *
                                 * and max range (stored in host byte *
                                 * order).                            *
                                 *                                    */
#define IP_FW_F_DRNG    0x0010  /* The first two dst ports are a min  *
                                 * and max range (stored in host byte *
                                 * order).                            *
                                 * (ports[0] <= port <= ports[1])     *
                                 *                                    */
#define IP_FW_F_PRN     0x0020  /* In verbose mode print this firewall*/
#define IP_FW_F_BIDIR   0x0040  /* For bidirectional firewalls        */
#define IP_FW_F_TCPSYN  0x0080  /* For tcp packets-check SYN only     */
#define IP_FW_F_ICMPRPL 0x0100  /* Send back icmp unreachable packet  */
#define IP_FW_F_MASQ    0x0200  /* Masquerading                       */
#define IP_FW_F_TCPACK  0x0400  /* For tcp-packets match if ACK is set*/
#define IP_FW_F_REDIR   0x0800  /* Redirect to local port fw_pts[n]   */
#define IP_FW_F_ACCTIN  0x1000  /* Account incoming packets only.     */
#define IP_FW_F_ACCTOUT 0x2000  /* Account outgoing packets only.     */

#define IP_FW_F_MASK    0x3FFF  /* All possible flag bits mask        */

/*
 *      New IP firewall options for [gs]etsockopt at the RAW IP level.
 *      Unlike BSD Linux inherits IP options so you don't have to use
 *      a raw socket for this. Instead we check rights in the calls.
 */


#define IP_FW_BASE_CTL          64      /* base for firewall socket options */

#define IP_FW_COMMAND           0x00FF  /* mask for command without chain */
#define IP_FW_TYPE              0x0300  /* mask for type (chain) */
#define IP_FW_SHIFT             8       /* shift count for type (chain) */

#define IP_FW_FWD               0
#define IP_FW_IN                1
#define IP_FW_OUT               2
#define IP_FW_ACCT              3
#define IP_FW_CHAINS            4       /* total number of ip_fw chains */
#define IP_FW_MASQ              5

#define IP_FW_INSERT            (IP_FW_BASE_CTL)
#define IP_FW_APPEND            (IP_FW_BASE_CTL+1)
#define IP_FW_DELETE            (IP_FW_BASE_CTL+2)
#define IP_FW_FLUSH             (IP_FW_BASE_CTL+3)
#define IP_FW_ZERO              (IP_FW_BASE_CTL+4)
#define IP_FW_POLICY            (IP_FW_BASE_CTL+5)
#define IP_FW_CHECK             (IP_FW_BASE_CTL+6)
#define IP_FW_MASQ_TIMEOUTS     (IP_FW_BASE_CTL+7)

#define IP_FW_INSERT_FWD        (IP_FW_INSERT | (IP_FW_FWD << IP_FW_SHIFT))
#define IP_FW_APPEND_FWD        (IP_FW_APPEND | (IP_FW_FWD << IP_FW_SHIFT))
#define IP_FW_DELETE_FWD        (IP_FW_DELETE | (IP_FW_FWD << IP_FW_SHIFT))
#define IP_FW_FLUSH_FWD         (IP_FW_FLUSH  | (IP_FW_FWD << IP_FW_SHIFT))
#define IP_FW_ZERO_FWD          (IP_FW_ZERO   | (IP_FW_FWD << IP_FW_SHIFT))
#define IP_FW_POLICY_FWD        (IP_FW_POLICY | (IP_FW_FWD << IP_FW_SHIFT))
#define IP_FW_CHECK_FWD         (IP_FW_CHECK  | (IP_FW_FWD << IP_FW_SHIFT))

#define IP_FW_INSERT_IN         (IP_FW_INSERT | (IP_FW_IN << IP_FW_SHIFT))
#define IP_FW_APPEND_IN         (IP_FW_APPEND | (IP_FW_IN << IP_FW_SHIFT))
#define IP_FW_DELETE_IN         (IP_FW_DELETE | (IP_FW_IN << IP_FW_SHIFT))
#define IP_FW_FLUSH_IN          (IP_FW_FLUSH  | (IP_FW_IN << IP_FW_SHIFT))
#define IP_FW_ZERO_IN           (IP_FW_ZERO   | (IP_FW_IN << IP_FW_SHIFT))
#define IP_FW_POLICY_IN         (IP_FW_POLICY | (IP_FW_IN << IP_FW_SHIFT))
#define IP_FW_CHECK_IN          (IP_FW_CHECK  | (IP_FW_IN << IP_FW_SHIFT))

#define IP_FW_INSERT_OUT        (IP_FW_INSERT | (IP_FW_OUT << IP_FW_SHIFT))
#define IP_FW_APPEND_OUT        (IP_FW_APPEND | (IP_FW_OUT << IP_FW_SHIFT))
#define IP_FW_DELETE_OUT        (IP_FW_DELETE | (IP_FW_OUT << IP_FW_SHIFT))
#define IP_FW_FLUSH_OUT         (IP_FW_FLUSH  | (IP_FW_OUT << IP_FW_SHIFT))
#define IP_FW_ZERO_OUT          (IP_FW_ZERO   | (IP_FW_OUT << IP_FW_SHIFT))
#define IP_FW_POLICY_OUT        (IP_FW_POLICY | (IP_FW_OUT << IP_FW_SHIFT))
#define IP_FW_CHECK_OUT         (IP_FW_CHECK  | (IP_FW_OUT << IP_FW_SHIFT))

#define IP_ACCT_INSERT          (IP_FW_INSERT | (IP_FW_ACCT << IP_FW_SHIFT))
#define IP_ACCT_APPEND          (IP_FW_APPEND | (IP_FW_ACCT << IP_FW_SHIFT))
#define IP_ACCT_DELETE          (IP_FW_DELETE | (IP_FW_ACCT << IP_FW_SHIFT))
#define IP_ACCT_FLUSH           (IP_FW_FLUSH  | (IP_FW_ACCT << IP_FW_SHIFT))
#define IP_ACCT_ZERO            (IP_FW_ZERO   | (IP_FW_ACCT << IP_FW_SHIFT))

#define IP_FW_MASQ_INSERT       (IP_FW_INSERT | (IP_FW_MASQ << IP_FW_SHIFT))
#define IP_FW_MASQ_ADD          (IP_FW_APPEND | (IP_FW_MASQ << IP_FW_SHIFT))
#define IP_FW_MASQ_DEL          (IP_FW_DELETE | (IP_FW_MASQ << IP_FW_SHIFT))
#define IP_FW_MASQ_FLUSH        (IP_FW_FLUSH  | (IP_FW_MASQ << IP_FW_SHIFT))

#define IP_FW_MASQ_INSERT       (IP_FW_INSERT | (IP_FW_MASQ << IP_FW_SHIFT))
#define IP_FW_MASQ_ADD          (IP_FW_APPEND | (IP_FW_MASQ << IP_FW_SHIFT))
#define IP_FW_MASQ_DEL          (IP_FW_DELETE | (IP_FW_MASQ << IP_FW_SHIFT))
#define IP_FW_MASQ_FLUSH        (IP_FW_FLUSH  | (IP_FW_MASQ << IP_FW_SHIFT))

struct ip_fwpkt
{
        struct iphdr fwp_iph;                   /* IP header */
        union {
                struct tcphdr fwp_tcph;         /* TCP header or */
                struct udphdr fwp_udph;         /* UDP header */
                struct icmphdr fwp_icmph;       /* ICMP header */
        } fwp_protoh;
        struct in_addr fwp_via;                 /* interface address */
        char           fwp_vianame[IFNAMSIZ];   /* interface name */
};

#define IP_FW_MASQCTL_MAX 256
#define IP_MASQ_MOD_NMAX  32

struct ip_fw_masqctl
{
        int mctl_action;
        union {
                struct {
                        char name[IP_MASQ_MOD_NMAX];
                        char data[1];
                } mod;
        } u;
};

/*
 * timeouts for ip masquerading
 */


struct ip_fw_masq;

/*
 *      Main firewall chains definitions and global var's definitions.
 */


#ifdef __KERNEL__

/* Modes used in the ip_fw_chk() routine. */
#define IP_FW_MODE_FW           0x00    /* kernel firewall check */
#define IP_FW_MODE_ACCT_IN      0x01    /* accounting (incoming) */
#define IP_FW_MODE_ACCT_OUT     0x02    /* accounting (outgoing) */
#define IP_FW_MODE_CHK          0x04    /* check requested by user */

#include <linux/config.h>
#ifdef CONFIG_IP_FIREWALL
extern struct ip_fw *ip_fw_in_chain;
extern struct ip_fw *ip_fw_out_chain;
extern struct ip_fw *ip_fw_fwd_chain;
extern int ip_fw_in_policy;
extern int ip_fw_out_policy;
extern int ip_fw_fwd_policy;
extern int ip_fw_ctl(int, void *, int);
#endif
#ifdef CONFIG_IP_ACCT
extern struct ip_fw *ip_acct_chain;
extern int ip_acct_ctl(int, void *, int);
#endif
#ifdef CONFIG_IP_MASQUERADE
extern int ip_masq_ctl(int, void *, int);
#endif
#ifdef CONFIG_IP_MASQUERADE
extern int ip_masq_ctl(int, void *, int);
#endif

extern int ip_fw_masq_timeouts(void *user, int len);

extern int ip_fw_chk(struct sk_buff **, struct net_device *, __u16 *,
                     struct ip_fw *, int, int);
#endif /* KERNEL */
#endif /* _IP_FW_H */