/*!\file netinet6/ip6_fw.h
 *
 */

/*
 * Copyright (C) 1998, 1999, 2000 and 2001 WIDE Project.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the project nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

/*
 * 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.
 *
 */

#ifndef _IP6_FW_H
#define _IP6_FW_H

#include <net/if.h>

/*
 * This union structure identifies an interface, either explicitly
 * by name or implicitly by IP address. The flags IP_FW_F_IIFNAME
 * and IP_FW_F_OIFNAME say how to interpret this structure. An
 * interface unit number of -1 matches any unit number, while an
 * IP address of 0.0.0.0 indicates matches any interface.
 *
 * The receive and transmit interfaces are only compared against the
 * the packet if the corresponding bit (IP_FW_F_IIFACE or IP_FW_F_OIFACE)
 * is set. Note some packets lack a receive or transmit interface
 * (in which case the missing "interface" never matches).
 */

union ip6_fw_if {
    struct in6_addr fu_via_ip6; /* Specified by IPv6 address */
    struct {            /* Specified by interface name */
#define IP6FW_IFNLEN     IFNAMSIZ
        char  name[IP6FW_IFNLEN];
        short unit;     /* -1 means match any unit */
    } fu_via_if;
};

/*
 * Format of an IP firewall descriptor
 *
 * fw_src, fw_dst, fw_smsk, fw_dmsk are always stored in network byte order.
 * fw_flg and fw_n*p are stored in host byte order (of course).
 * Port numbers are stored in HOST byte order.
 * Warning: setsockopt() will fail if sizeof(struct ip_fw) > MLEN (108)
 */

struct ip6_fw {
    u_long fw_pcnt,fw_bcnt;     /* Packet and byte counters */
    struct in6_addr fw_src, fw_dst; /* Source and destination IPv6 addr */
    struct in6_addr fw_smsk, fw_dmsk;   /* Mask for src and dest IPv6 addr */
    u_short fw_number;          /* Rule number */
    u_short fw_flg;         /* Flags word */
#define IPV6_FW_MAX_PORTS   10  /* A reasonable maximum */
    u_int fw_ipflg;         /* IP flags word */
    u_short fw_pts[IPV6_FW_MAX_PORTS];  /* Array of port numbers to match */
    u_char fw_ip6opt,fw_ip6nopt;    /* IPv6 options set/unset */
    u_char fw_tcpf,fw_tcpnf;        /* TCP flags set/unset */
#define IPV6_FW_ICMPTYPES_DIM (256 / (sizeof(unsigned) * 8))
    unsigned fw_icmp6types[IPV6_FW_ICMPTYPES_DIM]; /* ICMP types bitmap */
    long timestamp;         /* timestamp (tv_sec) of last match */
    union ip6_fw_if fw_in_if, fw_out_if;/* Incoming and outgoing interfaces */
    union {
    u_short fu_divert_port;     /* Divert/tee port (options IP6DIVERT) */
    u_short fu_skipto_rule;     /* SKIPTO command rule number */
    u_short fu_reject_code;     /* REJECT response code */
    } fw_un;
    u_char fw_prot;          /* IPv6 protocol */
    u_char fw_nports;        /* 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 IPV6_FW_GETNSRCP(rule)      ((rule)->fw_nports & 0x0f)
#define IPV6_FW_SETNSRCP(rule, n)       do {                \
                      (rule)->fw_nports &= ~0x0f;   \
                      (rule)->fw_nports |= (n); \
                    } while (0)
#define IPV6_FW_GETNDSTP(rule)      ((rule)->fw_nports >> 4)
#define IPV6_FW_SETNDSTP(rule, n)       do {                \
                      (rule)->fw_nports &= ~0xf0;   \
                      (rule)->fw_nports |= (n) << 4;\
                    } while (0)

#define fw_divert_port  fw_un.fu_divert_port
#define fw_skipto_rule  fw_un.fu_skipto_rule
#define fw_reject_code  fw_un.fu_reject_code

struct ip6_fw_chain {
        LIST_ENTRY(ip6_fw_chain) chain;
        struct ip6_fw    *rule;
};

/*
 * Values for "flags" field .
 */
#define IPV6_FW_F_IN        0x0001  /* Check inbound packets        */
#define IPV6_FW_F_OUT       0x0002  /* Check outbound packets       */
#define IPV6_FW_F_IIFACE    0x0004  /* Apply inbound interface test     */
#define IPV6_FW_F_OIFACE    0x0008  /* Apply outbound interface test    */

#define IPV6_FW_F_COMMAND   0x0070  /* Mask for type of chain entry:    */
#define IPV6_FW_F_DENY      0x0000  /* This is a deny rule          */
#define IPV6_FW_F_REJECT    0x0010  /* Deny and send a response packet  */
#define IPV6_FW_F_ACCEPT    0x0020  /* This is an accept rule       */
#define IPV6_FW_F_COUNT     0x0030  /* This is a count rule         */
#define IPV6_FW_F_DIVERT    0x0040  /* This is a divert rule        */
#define IPV6_FW_F_TEE       0x0050  /* This is a tee rule           */
#define IPV6_FW_F_SKIPTO    0x0060  /* This is a skipto rule        */

#define IPV6_FW_F_PRN       0x0080  /* Print if this rule matches       */

#define IPV6_FW_F_SRNG      0x0100  /* The first two src ports are a min    *
                                     * and max range (stored in host byte   *
                                     * order).              */

#define IPV6_FW_F_DRNG      0x0200  /* The first two dst ports are a min    *
                                     * and max range (stored in host byte   *
                                     * order).              */

#define IPV6_FW_F_IIFNAME   0x0400  /* In interface by name/unit (not IP)   */
#define IPV6_FW_F_OIFNAME   0x0800  /* Out interface by name/unit (not IP)  */

#define IPV6_FW_F_INVSRC    0x1000  /* Invert sense of src check        */
#define IPV6_FW_F_INVDST    0x2000  /* Invert sense of dst check        */

#define IPV6_FW_F_FRAG      0x4000  /* Fragment             */

#define IPV6_FW_F_ICMPBIT   0x8000    /* ICMP type bitmap is valid        */

#define IPV6_FW_F_MASK      0xFFFF  /* All possible flag bits mask      */

/*
 * Flags for the 'fw_ipflg' field, for comparing values of ip and its protocols. */
#define IPV6_FW_IF_TCPEST 0x00000020    /* established TCP connection   */
#define IPV6_FW_IF_TCPMSK 0x00000020    /* mask of all TCP values */

/*
 * For backwards compatibility with rules specifying "via iface" but
 * not restricted to only "in" or "out" packets, we define this combination
 * of bits to represent this configuration.
 */

#define IF6_FW_F_VIAHACK    (IPV6_FW_F_IN|IPV6_FW_F_OUT|IPV6_FW_F_IIFACE|IPV6_FW_F_OIFACE)

/*
 * Definitions for REJECT response codes.
 * Values less than 256 correspond to ICMP unreachable codes.
 */
#define IPV6_FW_REJECT_RST  0x0100      /* TCP packets: send RST */

/*
 * Definitions for IPv6 option names.
 */
#define IPV6_FW_IP6OPT_HOPOPT   0x01
#define IPV6_FW_IP6OPT_ROUTE    0x02
#define IPV6_FW_IP6OPT_FRAG     0x04
#define IPV6_FW_IP6OPT_ESP      0x08
#define IPV6_FW_IP6OPT_AH       0x10
#define IPV6_FW_IP6OPT_NONXT    0x20
#define IPV6_FW_IP6OPT_OPTS     0x40

/*
 * Definitions for TCP flags.
 */
#define IPV6_FW_TCPF_FIN    TH_FIN
#define IPV6_FW_TCPF_SYN    TH_SYN
#define IPV6_FW_TCPF_RST    TH_RST
#define IPV6_FW_TCPF_PSH    TH_PUSH
#define IPV6_FW_TCPF_ACK    TH_ACK
#define IPV6_FW_TCPF_URG    TH_URG

/*
 * Main firewall chains definitions and global var's definitions.
 */
#ifdef _KERNEL
#ifndef __SYS_MBUF_H
#include <sys/mbuf.h>
#endif

/*
 * Function definitions.
 */
void ip6_fw_init(void);

/* Firewall hooks */
struct ip6_hdr;
typedef int ip6_fw_chk_t (struct ip6_hdr**, struct ifnet*, u_short *, struct mbuf**);
typedef int ip6_fw_ctl_t (int, struct mbuf**);
extern  ip6_fw_chk_t *ip6_fw_chk_ptr;
extern  ip6_fw_ctl_t *ip6_fw_ctl_ptr;
extern  int ip6_fw_enable;

#endif /* _KERNEL */

#endif /* _IP6_FW_H */
