1 /* 2 * Copyright (c) 1982, 1986 Regents of the University of California. 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms are permitted 6 * provided that the above copyright notice and this paragraph are 7 * duplicated in all such forms and that any documentation, 8 * advertising materials, and other materials related to such 9 * distribution and use acknowledge that the software was developed 10 * by the University of California, Berkeley. The name of the 11 * University may not be used to endorse or promote products derived 12 * from this software without specific prior written permission. 13 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR 14 * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED 15 * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE. 16 * 17 * @(#)if.h 7.3 (Berkeley) 06/27/88 18 */ 19 20 /* 21 * Structures defining a network interface, providing a packet 22 * transport mechanism (ala level 0 of the PUP protocols). 23 * 24 * Each interface accepts output datagrams of a specified maximum 25 * length, and provides higher level routines with input datagrams 26 * received from its medium. 27 * 28 * Output occurs when the routine if_output is called, with three parameters: 29 * (*ifp->if_output)(ifp, m, dst) 30 * Here m is the mbuf chain to be sent and dst is the destination address. 31 * The output routine encapsulates the supplied datagram if necessary, 32 * and then transmits it on its medium. 33 * 34 * On input, each interface unwraps the data received by it, and either 35 * places it on the input queue of a internetwork datagram routine 36 * and posts the associated software interrupt, or passes the datagram to a raw 37 * packet input routine. 38 * 39 * Routines exist for locating interfaces by their addresses 40 * or for locating a interface on a certain network, as well as more general 41 * routing and gateway routines maintaining information used to locate 42 * interfaces. These routines live in the files if.c and route.c 43 */ 44 45 /* 46 * Structure defining a queue for a network interface. 47 * 48 * (Would like to call this struct ``if'', but C isn't PL/1.) 49 */ 50 struct ifnet { 51 char *if_name; /* name, e.g. ``en'' or ``lo'' */ 52 short if_unit; /* sub-unit for lower level driver */ 53 short if_mtu; /* maximum transmission unit */ 54 short if_flags; /* up/down, broadcast, etc. */ 55 short if_timer; /* time 'til if_watchdog called */ 56 int if_metric; /* routing metric (external only) */ 57 struct ifaddr *if_addrlist; /* linked list of addresses per if */ 58 struct ifqueue { 59 struct mbuf *ifq_head; 60 struct mbuf *ifq_tail; 61 int ifq_len; 62 int ifq_maxlen; 63 int ifq_drops; 64 } if_snd; /* output queue */ 65 /* procedure handles */ 66 int (*if_init)(); /* init routine */ 67 int (*if_output)(); /* output routine */ 68 int (*if_ioctl)(); /* ioctl routine */ 69 int (*if_reset)(); /* bus reset routine */ 70 int (*if_watchdog)(); /* timer routine */ 71 /* generic interface statistics */ 72 int if_ipackets; /* packets received on interface */ 73 int if_ierrors; /* input errors on interface */ 74 int if_opackets; /* packets sent on interface */ 75 int if_oerrors; /* output errors on interface */ 76 int if_collisions; /* collisions on csma interfaces */ 77 /* end statistics */ 78 struct ifnet *if_next; 79 }; 80 81 #define IFF_UP 0x1 /* interface is up */ 82 #define IFF_BROADCAST 0x2 /* broadcast address valid */ 83 #define IFF_DEBUG 0x4 /* turn on debugging */ 84 #define IFF_LOOPBACK 0x8 /* is a loopback net */ 85 #define IFF_POINTOPOINT 0x10 /* interface is point-to-point link */ 86 #define IFF_NOTRAILERS 0x20 /* avoid use of trailers */ 87 #define IFF_RUNNING 0x40 /* resources allocated */ 88 #define IFF_NOARP 0x80 /* no address resolution protocol */ 89 /* next two not supported now, but reserved: */ 90 #define IFF_PROMISC 0x100 /* receive all packets */ 91 #define IFF_ALLMULTI 0x200 /* receive all multicast packets */ 92 /* flags set internally only: */ 93 #define IFF_CANTCHANGE (IFF_BROADCAST | IFF_POINTOPOINT | IFF_RUNNING) 94 95 /* 96 * Output queues (ifp->if_snd) and internetwork datagram level (pup level 1) 97 * input routines have queues of messages stored on ifqueue structures 98 * (defined above). Entries are added to and deleted from these structures 99 * by these macros, which should be called with ipl raised to splimp(). 100 */ 101 #define IF_QFULL(ifq) ((ifq)->ifq_len >= (ifq)->ifq_maxlen) 102 #define IF_DROP(ifq) ((ifq)->ifq_drops++) 103 #define IF_ENQUEUE(ifq, m) { \ 104 (m)->m_act = 0; \ 105 if ((ifq)->ifq_tail == 0) \ 106 (ifq)->ifq_head = m; \ 107 else \ 108 (ifq)->ifq_tail->m_act = m; \ 109 (ifq)->ifq_tail = m; \ 110 (ifq)->ifq_len++; \ 111 } 112 #define IF_PREPEND(ifq, m) { \ 113 (m)->m_act = (ifq)->ifq_head; \ 114 if ((ifq)->ifq_tail == 0) \ 115 (ifq)->ifq_tail = (m); \ 116 (ifq)->ifq_head = (m); \ 117 (ifq)->ifq_len++; \ 118 } 119 /* 120 * Packets destined for level-1 protocol input routines 121 * have a pointer to the receiving interface prepended to the data. 122 * IF_DEQUEUEIF extracts and returns this pointer when dequeueing the packet. 123 * IF_ADJ should be used otherwise to adjust for its presence. 124 */ 125 #define IF_ADJ(m) { \ 126 (m)->m_off += sizeof(struct ifnet *); \ 127 (m)->m_len -= sizeof(struct ifnet *); \ 128 if ((m)->m_len == 0) { \ 129 struct mbuf *n; \ 130 MFREE((m), n); \ 131 (m) = n; \ 132 } \ 133 } 134 #define IF_DEQUEUEIF(ifq, m, ifp) { \ 135 (m) = (ifq)->ifq_head; \ 136 if (m) { \ 137 if (((ifq)->ifq_head = (m)->m_act) == 0) \ 138 (ifq)->ifq_tail = 0; \ 139 (m)->m_act = 0; \ 140 (ifq)->ifq_len--; \ 141 (ifp) = *(mtod((m), struct ifnet **)); \ 142 IF_ADJ(m); \ 143 } \ 144 } 145 #define IF_DEQUEUE(ifq, m) { \ 146 (m) = (ifq)->ifq_head; \ 147 if (m) { \ 148 if (((ifq)->ifq_head = (m)->m_act) == 0) \ 149 (ifq)->ifq_tail = 0; \ 150 (m)->m_act = 0; \ 151 (ifq)->ifq_len--; \ 152 } \ 153 } 154 155 #define IFQ_MAXLEN 50 156 #define IFNET_SLOWHZ 1 /* granularity is 1 second */ 157 158 /* 159 * The ifaddr structure contains information about one address 160 * of an interface. They are maintained by the different address families, 161 * are allocated and attached when an address is set, and are linked 162 * together so all addresses for an interface can be located. 163 */ 164 struct ifaddr { 165 struct sockaddr ifa_addr; /* address of interface */ 166 union { 167 struct sockaddr ifu_broadaddr; 168 struct sockaddr ifu_dstaddr; 169 } ifa_ifu; 170 #define ifa_broadaddr ifa_ifu.ifu_broadaddr /* broadcast address */ 171 #define ifa_dstaddr ifa_ifu.ifu_dstaddr /* other end of p-to-p link */ 172 struct ifnet *ifa_ifp; /* back-pointer to interface */ 173 struct ifaddr *ifa_next; /* next address for interface */ 174 }; 175 176 /* 177 * Interface request structure used for socket 178 * ioctl's. All interface ioctl's must have parameter 179 * definitions which begin with ifr_name. The 180 * remainder may be interface specific. 181 */ 182 struct ifreq { 183 #define IFNAMSIZ 16 184 char ifr_name[IFNAMSIZ]; /* if name, e.g. "en0" */ 185 union { 186 struct sockaddr ifru_addr; 187 struct sockaddr ifru_dstaddr; 188 struct sockaddr ifru_broadaddr; 189 short ifru_flags; 190 int ifru_metric; 191 caddr_t ifru_data; 192 } ifr_ifru; 193 #define ifr_addr ifr_ifru.ifru_addr /* address */ 194 #define ifr_dstaddr ifr_ifru.ifru_dstaddr /* other end of p-to-p link */ 195 #define ifr_broadaddr ifr_ifru.ifru_broadaddr /* broadcast address */ 196 #define ifr_flags ifr_ifru.ifru_flags /* flags */ 197 #define ifr_metric ifr_ifru.ifru_metric /* metric */ 198 #define ifr_data ifr_ifru.ifru_data /* for use by interface */ 199 }; 200 201 /* 202 * Structure used in SIOCGIFCONF request. 203 * Used to retrieve interface configuration 204 * for machine (useful for programs which 205 * must know all networks accessible). 206 */ 207 struct ifconf { 208 int ifc_len; /* size of associated buffer */ 209 union { 210 caddr_t ifcu_buf; 211 struct ifreq *ifcu_req; 212 } ifc_ifcu; 213 #define ifc_buf ifc_ifcu.ifcu_buf /* buffer address */ 214 #define ifc_req ifc_ifcu.ifcu_req /* array of structures returned */ 215 }; 216 217 #ifdef KERNEL 218 #include "../net/if_arp.h" 219 struct ifqueue rawintrq; /* raw packet input queue */ 220 struct ifnet *ifnet; 221 struct ifaddr *ifa_ifwithaddr(), *ifa_ifwithnet(); 222 struct ifaddr *ifa_ifwithdstaddr(); 223 #else KERNEL 224 #include <net/if_arp.h> 225 #endif KERNEL 226