+ short if_timer; /* time 'til if_watchdog called */
+ short if_flags; /* up/down, broadcast, etc. */
+ struct if_data {
+/* generic interface information */
+ u_char ifi_type; /* ethernet, tokenring, etc */
+ u_char ifi_addrlen; /* media address length */
+ u_char ifi_hdrlen; /* media header length */
+ u_long ifi_mtu; /* maximum transmission unit */
+ u_long ifi_metric; /* routing metric (external only) */
+ u_long ifi_baudrate; /* linespeed */
+/* volatile statistics */
+ u_long ifi_ipackets; /* packets received on interface */
+ u_long ifi_ierrors; /* input errors on interface */
+ u_long ifi_opackets; /* packets sent on interface */
+ u_long ifi_oerrors; /* output errors on interface */
+ u_long ifi_collisions; /* collisions on csma interfaces */
+ u_long ifi_ibytes; /* total number of octets received */
+ u_long ifi_obytes; /* total number of octets sent */
+ u_long ifi_imcasts; /* packets received via multicast */
+ u_long ifi_omcasts; /* packets sent via multicast */
+ u_long ifi_iqdrops; /* dropped on input, this interface */
+ u_long ifi_noproto; /* destined for unsupported protocol */
+ struct timeval ifi_lastchange;/* last updated */
+ } if_data;
+/* procedure handles */
+ int (*if_init) /* init routine */
+ __P((int));
+ int (*if_output) /* output routine (enqueue) */
+ __P((struct ifnet *, struct mbuf *, struct sockaddr *,
+ struct rtentry *));
+ int (*if_start) /* initiate output routine */
+ __P((struct ifnet *));
+ int (*if_done) /* output complete routine */
+ __P((struct ifnet *)); /* (XXX not used; fake prototype) */
+ int (*if_ioctl) /* ioctl routine */
+ __P((struct ifnet *, u_long, caddr_t));
+ int (*if_reset)
+ __P((int)); /* new autoconfig will permit removal */
+ int (*if_watchdog) /* timer routine */
+ __P((int));
+ struct ifqueue {
+ struct mbuf *ifq_head;
+ struct mbuf *ifq_tail;
+ int ifq_len;
+ int ifq_maxlen;
+ int ifq_drops;
+ } if_snd; /* output queue */
+};
+#define if_mtu if_data.ifi_mtu
+#define if_type if_data.ifi_type
+#define if_addrlen if_data.ifi_addrlen
+#define if_hdrlen if_data.ifi_hdrlen
+#define if_metric if_data.ifi_metric
+#define if_baudrate if_data.ifi_baudrate
+#define if_ipackets if_data.ifi_ipackets
+#define if_ierrors if_data.ifi_ierrors
+#define if_opackets if_data.ifi_opackets
+#define if_oerrors if_data.ifi_oerrors
+#define if_collisions if_data.ifi_collisions
+#define if_ibytes if_data.ifi_ibytes
+#define if_obytes if_data.ifi_obytes
+#define if_imcasts if_data.ifi_imcasts
+#define if_omcasts if_data.ifi_omcasts
+#define if_iqdrops if_data.ifi_iqdrops
+#define if_noproto if_data.ifi_noproto
+#define if_lastchange if_data.ifi_lastchange
+
+#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 */
+#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_LINK0 0x1000 /* per link layer defined bit */
+#define IFF_LINK1 0x2000 /* per link layer defined bit */
+#define IFF_LINK2 0x4000 /* per link layer defined bit */
+#define IFF_MULTICAST 0x8000 /* supports multicast */
+
+/* flags set internally only: */
+#define IFF_CANTCHANGE \
+ (IFF_BROADCAST|IFF_POINTOPOINT|IFF_RUNNING|IFF_OACTIVE|\
+ IFF_SIMPLEX|IFF_MULTICAST|IFF_ALLMULTI)
+
+/*
+ * 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 */
+ void (*ifa_rtrequest)(); /* check or clean routes (+ or -)'d */
+ u_short ifa_flags; /* mostly rt_flags for cloning */
+ short ifa_refcnt; /* extra to malloc for link info */
+ int ifa_metric; /* cost of going out this interface */
+#ifdef notdef
+ struct rtentry *ifa_rt; /* XXXX for ROUTETOIF ????? */
+#endif
+};
+#define IFA_ROUTE RTF_UP /* route installed */
+
+/*
+ * Message format for use in obtaining information about interfaces
+ * from getkerninfo and the routing socket
+ */
+struct if_msghdr {
+ u_short ifm_msglen; /* to skip over non-understood messages */
+ u_char ifm_version; /* future binary compatability */
+ u_char ifm_type; /* message type */
+ int ifm_addrs; /* like rtm_addrs */
+ int ifm_flags; /* value of if_flags */
+ u_short ifm_index; /* index for associated ifp */
+ struct if_data ifm_data;/* statistics and other data about if */