usr/src/sys/net/if.h

/*
 * Copyright (c) 1982, 1986, 1989 Regents of the University of California.
 * All rights reserved.
 *
 * %sccs.include.redist.c%
 *
 *      @(#)if.h        7.12 (Berkeley) %G%
 */

/*
 * Structures defining a network interface, providing a packet
 * transport mechanism (ala level 0 of the PUP protocols).
 *
 * Each interface accepts output datagrams of a specified maximum
 * length, and provides higher level routines with input datagrams
 * received from its medium.
 *
 * Output occurs when the routine if_output is called, with three parameters:
 *      (*ifp->if_output)(ifp, m, dst)
 * Here m is the mbuf chain to be sent and dst is the destination address.
 * The output routine encapsulates the supplied datagram if necessary,
 * and then transmits it on its medium.
 *
 * On input, each interface unwraps the data received by it, and either
 * places it on the input queue of a internetwork datagram routine
 * and posts the associated software interrupt, or passes the datagram to a raw
 * packet input routine.
 *
 * Routines exist for locating interfaces by their addresses
 * or for locating a interface on a certain network, as well as more general
 * routing and gateway routines maintaining information used to locate
 * interfaces.  These routines live in the files if.c and route.c
 */
#ifndef _TIME_ /*  XXX fast fix for SNMP, going away soon */
#ifdef KERNEL
#include "../sys/time.h"
#else
#include <sys/time.h>
#endif
#endif

/*
 * Structure defining a queue for a network interface.
 *
 * (Would like to call this struct ``if'', but C isn't PL/1.)
 */

struct ifnet {
        char    *if_name;               /* name, e.g. ``en'' or ``lo'' */
        short   if_unit;                /* sub-unit for lower level driver */
        short   if_mtu;                 /* maximum transmission unit */
        short   if_flags;               /* up/down, broadcast, etc. */
        short   if_timer;               /* time 'til if_watchdog called */
        int     if_metric;              /* routing metric (external only) */
        struct  ifaddr *if_addrlist;    /* linked list of addresses per if */
        struct  ifqueue {
                struct  mbuf *ifq_head;
                struct  mbuf *ifq_tail;
                int     ifq_len;
                int     ifq_maxlen;
                int     ifq_drops;
        } if_snd;                       /* output queue */
/* procedure handles */
        int     (*if_init)();           /* init routine */
        int     (*if_output)();         /* output routine (enqueue) */
        int     (*if_start)();          /* initiate output routine */
        int     (*if_done)();           /* output complete routine */
        int     (*if_ioctl)();          /* ioctl routine */
        int     (*if_reset)();          /* bus reset routine */
        int     (*if_watchdog)();       /* timer routine */
/* generic interface statistics */
        int     if_ipackets;            /* packets received on interface */
        int     if_ierrors;             /* input errors on interface */
        int     if_opackets;            /* packets sent on interface */
        int     if_oerrors;             /* output errors on interface */
        int     if_collisions;          /* collisions on csma interfaces */
/* end statistics */
        struct  ifnet *if_next;
        u_char  if_type;                /* ethernet, tokenring, etc */
        u_char  if_addrlen;             /* media address length */
        u_char  if_hdrlen;              /* media header length */
        u_char  if_index;               /* numeric abbreviation for this if  */
/* more statistics here to avoid recompiling netstat */
        struct  timeval if_lastchange;  /* last updated */
        int     if_ibytes;              /* total number of octets received */
        int     if_obytes;              /* total number of octets sent */
        int     if_imcasts;             /* packets received via multicast */
        int     if_omcasts;             /* packets sent via multicast */
        int     if_iqdrops;             /* dropped on input, this interface */
        int     if_noproto;             /* destined for unsupported protocol */
        int     if_baudrate;            /* linespeed */
        int     if_pcount;              /* number of promiscuous listeners */
};

#define IFF_UP          0x1             /* interface is up */
#define IFF_BROADCAST   0x2             /* broadcast address valid */
#define IFF_DEBUG       0x4             /* turn on debugging */
#define IFF_LOOPBACK    0x8             /* is a loopback net */
#define IFF_POINTOPOINT 0x10            /* interface is point-to-point link */
#define IFF_NOTRAILERS  0x20            /* avoid use of trailers */
#define IFF_RUNNING     0x40            /* resources allocated */
#define IFF_NOARP       0x80            /* no address resolution protocol */
/* next two not supported now, but reserved: */
#define IFF_PROMISC     0x100           /* receive all packets */
#define IFF_ALLMULTI    0x200           /* receive all multicast packets */
#define IFF_OACTIVE     0x400           /* transmission in progress */
#define IFF_SIMPLEX     0x800           /* can't hear own transmissions */
#define IFF_LLC0        0x1000          /* per link layer defined bit */
#define IFF_LLC1        0x2000          /* per link layer defined bit */
#define IFF_LLC2        0x4000          /* per link layer defined bit */

/* flags set internally only: */
#define IFF_CANTCHANGE \
        (IFF_BROADCAST|IFF_POINTOPOINT|IFF_RUNNING|IFF_OACTIVE|IFF_SIMPLEX)

/*
 * Output queues (ifp->if_snd) and internetwork datagram level (pup level 1)
 * input routines have queues of messages stored on ifqueue structures
 * (defined above).  Entries are added to and deleted from these structures
 * by these macros, which should be called with ipl raised to splimp().
 */
#define IF_QFULL(ifq)           ((ifq)->ifq_len >= (ifq)->ifq_maxlen)
#define IF_DROP(ifq)            ((ifq)->ifq_drops++)
#define IF_ENQUEUE(ifq, m) { \
        (m)->m_nextpkt = 0; \
        if ((ifq)->ifq_tail == 0) \
                (ifq)->ifq_head = m; \
        else \
                (ifq)->ifq_tail->m_nextpkt = m; \
        (ifq)->ifq_tail = m; \
        (ifq)->ifq_len++; \
}
#define IF_PREPEND(ifq, m) { \
        (m)->m_nextpkt = (ifq)->ifq_head; \
        if ((ifq)->ifq_tail == 0) \
                (ifq)->ifq_tail = (m); \
        (ifq)->ifq_head = (m); \
        (ifq)->ifq_len++; \
}
#define IF_DEQUEUE(ifq, m) { \
        (m) = (ifq)->ifq_head; \
        if (m) { \
                if (((ifq)->ifq_head = (m)->m_nextpkt) == 0) \
                        (ifq)->ifq_tail = 0; \
                (m)->m_nextpkt = 0; \
                (ifq)->ifq_len--; \
        } \
}

#define IFQ_MAXLEN      50
#define IFNET_SLOWHZ    1               /* granularity is 1 second */

/*
 * The ifaddr structure contains information about one address
 * of an interface.  They are maintained by the different address families,
 * are allocated and attached when an address is set, and are linked
 * together so all addresses for an interface can be located.
 */
struct ifaddr {
        struct  sockaddr *ifa_addr;     /* address of interface */
        struct  sockaddr *ifa_dstaddr;  /* other end of p-to-p link */
#define ifa_broadaddr   ifa_dstaddr     /* broadcast address interface */
        struct  sockaddr *ifa_netmask;  /* used to determine subnet */
        struct  ifnet *ifa_ifp;         /* back-pointer to interface */
        struct  ifaddr *ifa_next;       /* next address for interface */
        int     (*ifa_rtrequest)();     /* check or clean routes (+ or -)'d */
        struct  rtentry *ifa_rt;        /* ??? for ROUTETOIF */
        u_short ifa_flags;              /* mostly rt_flags for cloning */
        u_short ifa_llinfolen;          /* extra to malloc for link info */
};
#define IFA_ROUTE       RTF_UP          /* route installed */
/*
 * Interface request structure used for socket
 * ioctl's.  All interface ioctl's must have parameter
 * definitions which begin with ifr_name.  The
 * remainder may be interface specific.
 */
struct  ifreq {
#define IFNAMSIZ        16
        char    ifr_name[IFNAMSIZ];             /* if name, e.g. "en0" */
        union {
                struct  sockaddr ifru_addr;
                struct  sockaddr ifru_dstaddr;
                struct  sockaddr ifru_broadaddr;
                short   ifru_flags;
                int     ifru_metric;
                caddr_t ifru_data;
        } ifr_ifru;
#define ifr_addr        ifr_ifru.ifru_addr      /* address */
#define ifr_dstaddr     ifr_ifru.ifru_dstaddr   /* other end of p-to-p link */
#define ifr_broadaddr   ifr_ifru.ifru_broadaddr /* broadcast address */
#define ifr_flags       ifr_ifru.ifru_flags     /* flags */
#define ifr_metric      ifr_ifru.ifru_metric    /* metric */
#define ifr_data        ifr_ifru.ifru_data      /* for use by interface */
};

struct ifaliasreq {
        char    ifra_name[IFNAMSIZ];            /* if name, e.g. "en0" */
        struct  sockaddr ifra_addr;
        struct  sockaddr ifra_broadaddr;
        struct  sockaddr ifra_mask;
};

/*
 * Structure used in SIOCGIFCONF request.
 * Used to retrieve interface configuration
 * for machine (useful for programs which
 * must know all networks accessible).
 */
struct  ifconf {
        int     ifc_len;                /* size of associated buffer */
        union {
                caddr_t ifcu_buf;
                struct  ifreq *ifcu_req;
        } ifc_ifcu;
#define ifc_buf ifc_ifcu.ifcu_buf       /* buffer address */
#define ifc_req ifc_ifcu.ifcu_req       /* array of structures returned */
};

#ifdef KERNEL
#include "../net/if_arp.h"
struct  ifqueue rawintrq;               /* raw packet input queue */
struct  ifnet *ifnet;
struct  ifaddr *ifa_ifwithaddr(), *ifa_ifwithnet();
struct  ifaddr *ifa_ifwithdstaddr();
#else KERNEL
#include <net/if_arp.h>
#endif KERNEL