/*      $NetBSD: ip_var.h,v 1.135 2025/06/27 21:36:23 andvar Exp $      */

/*
 * Copyright (c) 1982, 1986, 1993
 *      The Regents of the University of California.  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 University 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 REGENTS 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 REGENTS 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.
 *
 *      @(#)ip_var.h    8.2 (Berkeley) 1/9/95
 */

#ifndef _NETINET_IP_VAR_H_
#define _NETINET_IP_VAR_H_

#include <sys/queue.h>
#include <net/route.h>

/*
 * Overlay for ip header used by other protocols (tcp, udp).
 */
struct ipovly {
        u_int8_t  ih_x1[9];             /* (unused) */
        u_int8_t  ih_pr;                /* protocol */
        u_int16_t ih_len;               /* protocol length */
        struct    in_addr ih_src;       /* source internet address */
        struct    in_addr ih_dst;       /* destination internet address */
};
#ifdef __CTASSERT
__CTASSERT(sizeof(struct ipovly) == 20);
#endif

/*
 * IP Flow structure
 */
struct ipflow {
        TAILQ_ENTRY(ipflow) ipf_list;   /* next in active list */
        TAILQ_ENTRY(ipflow) ipf_hash;   /* next ipflow in bucket */
        size_t ipf_hashidx;             /* own hash index of ipflowtable[] */
        struct in_addr ipf_dst;         /* destination address */
        struct in_addr ipf_src;         /* source address */
        uint8_t ipf_tos;                /* type-of-service */
        struct route ipf_ro;            /* associated route entry */
        u_long ipf_uses;                /* number of uses in this period */
        u_long ipf_last_uses;           /* number of uses in last period */
        u_long ipf_dropped;             /* ENOBUFS returned by if_output */
        u_long ipf_errors;              /* other errors returned by if_output */
        u_int ipf_timer;                /* lifetime timer */
};

/*
 * TCP sequence queue structure.
 */
TAILQ_HEAD(ipqehead, ipqent);
struct ipqent {
        TAILQ_ENTRY(ipqent) ipqe_q;
        struct mbuf *ipqe_m;
        TAILQ_ENTRY(ipqent) ipqe_timeq;
        u_int32_t ipqe_seq;
        u_int32_t ipqe_len;
        u_int32_t ipqe_flags;
};

/*
 * Structure stored in mbuf in inpcb.ip_options
 * and passed to ip_output when ip options are in use.
 * The actual length of the options (including ipopt_dst)
 * is in m_len.
 */
#define MAX_IPOPTLEN    40

struct ipoption {
        struct  in_addr ipopt_dst;      /* first-hop dst if source routed */
        int8_t  ipopt_list[MAX_IPOPTLEN];       /* options proper */
};

/*
 * Structure attached to inpcb.ip_moptions and
 * passed to ip_output when IP multicast options are in use.
 */
struct ip_moptions {
        if_index_t imo_multicast_if_index; /* I/F for outgoing multicasts */
        struct in_addr imo_multicast_addr; /* ifindex/addr on MULTICAST_IF */
        u_int8_t  imo_multicast_ttl;    /* TTL for outgoing multicasts */
        u_int8_t  imo_multicast_loop;   /* 1 => hear sends if a member */
        u_int16_t imo_num_memberships;  /* no. memberships this socket */
        struct    in_multi *imo_membership[IP_MAX_MEMBERSHIPS];
};

struct ip_pktopts {
        struct sockaddr_in ippo_laddr;  /* source address */
        struct ip_moptions *ippo_imo;   /* inp->inp_moptions or &ippo_imobuf */
        struct ip_moptions ippo_imobuf; /* use when IP_PKTINFO */
};

/*
 * IP statistics.
 * Each counter is an unsigned 64-bit value.
 */
#define IP_STAT_TOTAL           0       /* total packets received */
#define IP_STAT_BADSUM          1       /* checksum bad */
#define IP_STAT_TOOSHORT        2       /* packet too short */
#define IP_STAT_TOOSMALL        3       /* not enough data */
#define IP_STAT_BADHLEN         4       /* ip header length < data size */
#define IP_STAT_BADLEN          5       /* ip length < ip header length */
#define IP_STAT_FRAGMENTS       6       /* fragments received */
#define IP_STAT_FRAGDROPPED     7       /* frags dropped (dups, out of space) */
#define IP_STAT_FRAGTIMEOUT     8       /* fragments timed out */
#define IP_STAT_FORWARD         9       /* packets forwarded */
#define IP_STAT_FASTFORWARD     10      /* packets fast forwarded */
#define IP_STAT_CANTFORWARD     11      /* packets rcvd for unreachable dest */
#define IP_STAT_REDIRECTSENT    12      /* packets forwarded on same net */
#define IP_STAT_NOPROTO         13      /* unknown or unsupported protocol */
#define IP_STAT_DELIVERED       14      /* datagrams delivered to upper level */
#define IP_STAT_LOCALOUT        15      /* total ip packets generated here */
#define IP_STAT_ODROPPED        16      /* lost packets due to nobufs, etc. */
#define IP_STAT_REASSEMBLED     17      /* total packets reassembled ok */
#define IP_STAT_FRAGMENTED      18      /* datagrams successfully fragmented */
#define IP_STAT_OFRAGMENTS      19      /* output fragments created */
#define IP_STAT_CANTFRAG        20      /* don't fragment flag was set, etc. */
#define IP_STAT_BADOPTIONS      21      /* error in option processing */
#define IP_STAT_NOROUTE         22      /* packets discarded due to no route */
#define IP_STAT_BADVERS         23      /* ip version != 4 */
#define IP_STAT_RAWOUT          24      /* total raw ip packets generated */
#define IP_STAT_BADFRAGS        25      /* malformed fragments (bad length) */
#define IP_STAT_RCVMEMDROP      26      /* frags dropped for lack of memory */
#define IP_STAT_TOOLONG         27      /* ip length > max ip packet size */
#define IP_STAT_NOGIF           28      /* no match gif found */
#define IP_STAT_BADADDR         29      /* invalid address on header */
#define IP_STAT_NOL2TP          30      /* no match l2tp found */
#define IP_STAT_NOIPSEC         31      /* no match ipsec(4) found */
#define IP_STAT_PFILDROP_IN     32      /* dropped by pfil (PFIL_IN) */
#define IP_STAT_PFILDROP_OUT    33      /* dropped by pfil (PFIL_OUT) */
#define IP_STAT_IPSECDROP_IN    34      /* dropped by IPsec SP check */
#define IP_STAT_IPSECDROP_OUT   35      /* dropped by IPsec SP check */
#define IP_STAT_IFDROP          36      /* dropped due to interface state */
#define IP_STAT_TIMXCEED        37      /* time to live exceeded */
#define IP_STAT_IFNOADDR        38      /* interface has no IP address */
#define IP_STAT_RTREJECT        39      /* rejected by route */
#define IP_STAT_BCASTDENIED     40      /* broadcast prohibited */

#define IP_NSTATS               41

#ifdef _KERNEL

#ifdef _KERNEL_OPT
#include "opt_gateway.h"
#include "opt_mbuftrace.h"
#endif

/*
 * The following flags can be passed to ip_output() as last parameter
 */
#define IP_FORWARDING           0x0001          /* most of ip header exists */
#define IP_RAWOUTPUT            0x0002          /* raw ip header exists */
#define IP_RETURNMTU            0x0004          /* pass back mtu on EMSGSIZE */
#define IP_NOIPNEWID            0x0008          /* don't fill in ip_id */
__CTASSERT(SO_DONTROUTE ==      0x0010);
__CTASSERT(SO_BROADCAST ==      0x0020);
#define IP_ROUTETOIF            SO_DONTROUTE    /* bypass routing tables */
#define IP_ALLOWBROADCAST       SO_BROADCAST    /* can send broadcast packets */

#define IP_IGMP_MCAST           0x0040          /* IGMP for mcast join/leave */
#define IP_MTUDISC              0x0400          /* Path MTU Discovery; set DF */
#define IP_ROUTETOIFINDEX       0x0800  /* force route imo_multicast_if_index */

extern struct domain inetdomain;
extern const struct pr_usrreqs rip_usrreqs;

extern int   ip_defttl;                 /* default IP ttl */
extern int   ipforwarding;              /* ip forwarding */
extern int   ip_mtudisc;                /* mtu discovery */
extern int   ip_mtudisc_timeout;        /* seconds to timeout mtu discovery */
extern int   anonportmin;               /* minimum ephemeral port */
extern int   anonportmax;               /* maximum ephemeral port */
extern int   lowportmin;                /* minimum reserved port */
extern int   lowportmax;                /* maximum reserved port */
extern int   ip_do_loopback_cksum;      /* do IP checksum on loopback? */
extern struct rttimer_queue *ip_mtudisc_timeout_q;
#ifdef MBUFTRACE
extern struct mowner ip_rx_mowner;
extern struct mowner ip_tx_mowner;
#endif
struct   inpcb;
struct   sockopt;

void    ip_init(void);
void    in_init(void);

int      ip_ctloutput(int, struct socket *, struct sockopt *);
int      ip_setpktopts(struct mbuf *, struct ip_pktopts *, int *,
            struct inpcb *, kauth_cred_t);
void     ip_drain(void);
void     ip_drainstub(void);
void     ip_freemoptions(struct ip_moptions *);
int      ip_optcopy(struct ip *, struct ip *);
u_int    ip_optlen(struct inpcb *);
int      ip_output(struct mbuf *, struct mbuf *, struct route *, int,
            struct ip_moptions *, struct inpcb *);
int      ip_fragment(struct mbuf *, struct ifnet *, u_long);

void     ip_reass_init(void);
int      ip_reass_packet(struct mbuf **);
void     ip_reass_slowtimo(void);
void     ip_reass_drain(void);

void     ip_savecontrol(struct inpcb *, struct mbuf **, struct ip *,
           struct mbuf *);
void     ip_slowtimo(void);
void     ip_fasttimo(void);
struct mbuf *
         ip_srcroute(struct mbuf *);
int      ip_sysctl(int *, u_int, void *, size_t *, void *, size_t);
void     ip_statinc(u_int);
void *   rip_ctlinput(int, const struct sockaddr *, void *);
int      rip_ctloutput(int, struct socket *, struct sockopt *);
void     rip_init(void);
void     rip_input(struct mbuf *, int, int);
int      rip_output(struct mbuf *, struct inpcb *, struct mbuf *, struct lwp *);
int      rip_usrreq(struct socket *,
            int, struct mbuf *, struct mbuf *, struct mbuf *, struct lwp *);

int     ip_setmoptions(struct ip_moptions **, const struct sockopt *sopt);
int     ip_getmoptions(struct ip_moptions *, struct sockopt *sopt);

int     ip_if_output(struct ifnet * const, struct mbuf * const,
            const struct sockaddr * const, const struct rtentry *);

/* IP Flow interface. */
void    ipflow_init(void);
void    ipflow_poolinit(void);
void    ipflow_create(struct route *, struct mbuf *);
void    ipflow_slowtimo(void);
int     ipflow_invalidate_all(int);

#endif  /* _KERNEL */

#endif /* !_NETINET_IP_VAR_H_ */