1 /* 2 * Copyright (c) 1982 Regents of the University of California. 3 * All rights reserved. The Berkeley software License Agreement 4 * specifies the terms and conditions for redistribution. 5 * 6 * @(#)if.h 6.13 (Berkeley) 05/14/86 7 */ 8 9 /* 10 * Structures defining a network interface, providing a packet 11 * transport mechanism (ala level 0 of the PUP protocols). 12 * 13 * Each interface accepts output datagrams of a specified maximum 14 * length, and provides higher level routines with input datagrams 15 * received from its medium. 16 * 17 * Output occurs when the routine if_output is called, with three parameters: 18 * (*ifp->if_output)(ifp, m, dst) 19 * Here m is the mbuf chain to be sent and dst is the destination address. 20 * The output routine encapsulates the supplied datagram if necessary, 21 * and then transmits it on its medium. 22 * 23 * On input, each interface unwraps the data received by it, and either 24 * places it on the input queue of a internetwork datagram routine 25 * and posts the associated software interrupt, or passes the datagram to a raw 26 * packet input routine. 27 * 28 * Routines exist for locating interfaces by their addresses 29 * or for locating a interface on a certain network, as well as more general 30 * routing and gateway routines maintaining information used to locate 31 * interfaces. These routines live in the files if.c and route.c 32 */ 33 34 /* 35 * Structure defining a queue for a network interface. 36 * 37 * (Would like to call this struct ``if'', but C isn't PL/1.) 38 */ 39 struct ifnet { 40 char *if_name; /* name, e.g. ``en'' or ``lo'' */ 41 short if_unit; /* sub-unit for lower level driver */ 42 short if_mtu; /* maximum transmission unit */ 43 short if_flags; /* up/down, broadcast, etc. */ 44 short if_timer; /* time 'til if_watchdog called */ 45 int if_metric; /* routing metric (external only) */ 46 struct ifaddr *if_addrlist; /* linked list of addresses per if */ 47 struct ifqueue { 48 struct mbuf *ifq_head; 49 struct mbuf *ifq_tail; 50 int ifq_len; 51 int ifq_maxlen; 52 int ifq_drops; 53 } if_snd; /* output queue */ 54 /* procedure handles */ 55 int (*if_init)(); /* init routine */ 56 int (*if_output)(); /* output routine */ 57 int (*if_ioctl)(); /* ioctl routine */ 58 int (*if_reset)(); /* bus reset routine */ 59 int (*if_watchdog)(); /* timer routine */ 60 /* generic interface statistics */ 61 int if_ipackets; /* packets received on interface */ 62 int if_ierrors; /* input errors on interface */ 63 int if_opackets; /* packets sent on interface */ 64 int if_oerrors; /* output errors on interface */ 65 int if_collisions; /* collisions on csma interfaces */ 66 /* end statistics */ 67 struct ifnet *if_next; 68 }; 69 70 #define IFF_UP 0x1 /* interface is up */ 71 #define IFF_BROADCAST 0x2 /* broadcast address valid */ 72 #define IFF_DEBUG 0x4 /* turn on debugging */ 73 #define IFF_LOOPBACK 0x8 /* is a loopback net */ 74 #define IFF_POINTOPOINT 0x10 /* interface is point-to-point link */ 75 #define IFF_NOTRAILERS 0x20 /* avoid use of trailers */ 76 #define IFF_RUNNING 0x40 /* resources allocated */ 77 #define IFF_NOARP 0x80 /* no address resolution protocol */ 78 /* next two not supported now, but reserved: */ 79 #define IFF_PROMISC 0x100 /* receive all packets */ 80 #define IFF_ALLMULTI 0x200 /* receive all multicast packets */ 81 /* flags set internally only: */ 82 #define IFF_CANTCHANGE (IFF_BROADCAST | IFF_POINTOPOINT | IFF_RUNNING) 83 84 /* 85 * Output queues (ifp->if_snd) and internetwork datagram level (pup level 1) 86 * input routines have queues of messages stored on ifqueue structures 87 * (defined above). Entries are added to and deleted from these structures 88 * by these macros, which should be called with ipl raised to splimp(). 89 */ 90 #define IF_QFULL(ifq) ((ifq)->ifq_len >= (ifq)->ifq_maxlen) 91 #define IF_DROP(ifq) ((ifq)->ifq_drops++) 92 #define IF_ENQUEUE(ifq, m) { \ 93 (m)->m_act = 0; \ 94 if ((ifq)->ifq_tail == 0) \ 95 (ifq)->ifq_head = m; \ 96 else \ 97 (ifq)->ifq_tail->m_act = m; \ 98 (ifq)->ifq_tail = m; \ 99 (ifq)->ifq_len++; \ 100 } 101 #define IF_PREPEND(ifq, m) { \ 102 (m)->m_act = (ifq)->ifq_head; \ 103 if ((ifq)->ifq_tail == 0) \ 104 (ifq)->ifq_tail = (m); \ 105 (ifq)->ifq_head = (m); \ 106 (ifq)->ifq_len++; \ 107 } 108 /* 109 * Packets destined for level-1 protocol input routines 110 * have a pointer to the receiving interface prepended to the data. 111 * IF_DEQUEUEIF extracts and returns this pointer when dequeueing the packet. 112 * IF_ADJ should be used otherwise to adjust for its presence. 113 */ 114 #define IF_ADJ(m) { \ 115 (m)->m_off += sizeof(struct ifnet *); \ 116 (m)->m_len -= sizeof(struct ifnet *); \ 117 if ((m)->m_len == 0) { \ 118 struct mbuf *n; \ 119 MFREE((m), n); \ 120 (m) = n; \ 121 } \ 122 } 123 #define IF_DEQUEUEIF(ifq, m, ifp) { \ 124 (m) = (ifq)->ifq_head; \ 125 if (m) { \ 126 if (((ifq)->ifq_head = (m)->m_act) == 0) \ 127 (ifq)->ifq_tail = 0; \ 128 (m)->m_act = 0; \ 129 (ifq)->ifq_len--; \ 130 (ifp) = *(mtod((m), struct ifnet **)); \ 131 IF_ADJ(m); \ 132 } \ 133 } 134 #define IF_DEQUEUE(ifq, m) { \ 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 } \ 142 } 143 144 #define IFQ_MAXLEN 50 145 #define IFNET_SLOWHZ 1 /* granularity is 1 second */ 146 147 /* 148 * The ifaddr structure contains information about one address 149 * of an interface. They are maintained by the different address families, 150 * are allocated and attached when an address is set, and are linked 151 * together so all addresses for an interface can be located. 152 */ 153 struct ifaddr { 154 struct sockaddr ifa_addr; /* address of interface */ 155 union { 156 struct sockaddr ifu_broadaddr; 157 struct sockaddr ifu_dstaddr; 158 } ifa_ifu; 159 #define ifa_broadaddr ifa_ifu.ifu_broadaddr /* broadcast address */ 160 #define ifa_dstaddr ifa_ifu.ifu_dstaddr /* other end of p-to-p link */ 161 struct ifnet *ifa_ifp; /* back-pointer to interface */ 162 struct ifaddr *ifa_next; /* next address for interface */ 163 }; 164 165 /* 166 * Interface request structure used for socket 167 * ioctl's. All interface ioctl's must have parameter 168 * definitions which begin with ifr_name. The 169 * remainder may be interface specific. 170 */ 171 struct ifreq { 172 #define IFNAMSIZ 16 173 char ifr_name[IFNAMSIZ]; /* if name, e.g. "en0" */ 174 union { 175 struct sockaddr ifru_addr; 176 struct sockaddr ifru_dstaddr; 177 struct sockaddr ifru_broadaddr; 178 short ifru_flags; 179 int ifru_metric; 180 caddr_t ifru_data; 181 } ifr_ifru; 182 #define ifr_addr ifr_ifru.ifru_addr /* address */ 183 #define ifr_dstaddr ifr_ifru.ifru_dstaddr /* other end of p-to-p link */ 184 #define ifr_broadaddr ifr_ifru.ifru_broadaddr /* broadcast address */ 185 #define ifr_flags ifr_ifru.ifru_flags /* flags */ 186 #define ifr_metric ifr_ifru.ifru_metric /* metric */ 187 #define ifr_data ifr_ifru.ifru_data /* for use by interface */ 188 }; 189 190 /* 191 * Structure used in SIOCGIFCONF request. 192 * Used to retrieve interface configuration 193 * for machine (useful for programs which 194 * must know all networks accessible). 195 */ 196 struct ifconf { 197 int ifc_len; /* size of associated buffer */ 198 union { 199 caddr_t ifcu_buf; 200 struct ifreq *ifcu_req; 201 } ifc_ifcu; 202 #define ifc_buf ifc_ifcu.ifcu_buf /* buffer address */ 203 #define ifc_req ifc_ifcu.ifcu_req /* array of structures returned */ 204 }; 205 206 #ifdef KERNEL 207 #include "../net/if_arp.h" 208 #ifdef INET 209 struct ifqueue ipintrq; /* ip packet input queue */ 210 #endif 211 struct ifqueue rawintrq; /* raw packet input queue */ 212 struct ifnet *ifnet; 213 struct ifaddr *ifa_ifwithaddr(), *ifa_ifwithnet(), *ifa_ifwithaf(); 214 struct ifaddr *ifa_ifwithdstaddr(); 215 #else KERNEL 216 #include <net/if_arp.h> 217 #endif KERNEL 218