xref: /original-bsd/sys/net/if.h (revision 39a1d63c)
1 /*
2  * Copyright (c) 1982, 1986, 1989 Regents of the University of California.
3  * All rights reserved.
4  *
5  * %sccs.include.redist.c%
6  *
7  *	@(#)if.h	7.19 (Berkeley) 07/09/92
8  */
9 
10 /*
11  * Structures defining a network interface, providing a packet
12  * transport mechanism (ala level 0 of the PUP protocols).
13  *
14  * Each interface accepts output datagrams of a specified maximum
15  * length, and provides higher level routines with input datagrams
16  * received from its medium.
17  *
18  * Output occurs when the routine if_output is called, with three parameters:
19  *	(*ifp->if_output)(ifp, m, dst, rt)
20  * Here m is the mbuf chain to be sent and dst is the destination address.
21  * The output routine encapsulates the supplied datagram if necessary,
22  * and then transmits it on its medium.
23  *
24  * On input, each interface unwraps the data received by it, and either
25  * places it on the input queue of a internetwork datagram routine
26  * and posts the associated software interrupt, or passes the datagram to a raw
27  * packet input routine.
28  *
29  * Routines exist for locating interfaces by their addresses
30  * or for locating a interface on a certain network, as well as more general
31  * routing and gateway routines maintaining information used to locate
32  * interfaces.  These routines live in the files if.c and route.c
33  */
34 #ifndef _TIME_ /*  XXX fast fix for SNMP, going away soon */
35 #ifdef KERNEL
36 #include "../sys/time.h"
37 #else
38 #include <sys/time.h>
39 #endif
40 #endif
41 
42 #ifdef __STDC__
43 /*
44  * Forward structure declarations for function prototypes [sic].
45  */
46 struct	rtentry;
47 struct	mbuf;
48 #endif
49 /*
50  * Structure describing information about an interface
51  * which may be of interest to management entities.
52  */
53 /*
54  * Structure defining a queue for a network interface.
55  *
56  * (Would like to call this struct ``if'', but C isn't PL/1.)
57  */
58 
59 struct ifnet {
60 	char	*if_name;		/* name, e.g. ``en'' or ``lo'' */
61 	struct	ifnet *if_next;		/* all struct ifnets are chained */
62 	struct	ifaddr *if_addrlist;	/* linked list of addresses per if */
63         int	if_pcount;		/* number of promiscuous listeners */
64 	caddr_t	if_bpf;			/* packet filter structure */
65 	u_short	if_index;		/* numeric abbreviation for this if  */
66 	short	if_unit;		/* sub-unit for lower level driver */
67 	short	if_timer;		/* time 'til if_watchdog called */
68 	short	if_flags;		/* up/down, broadcast, etc. */
69 	struct	if_data {
70 /* generic interface information */
71 		u_char	ifi_type;	/* ethernet, tokenring, etc */
72 		u_char	ifi_addrlen;	/* media address length */
73 		u_char	ifi_hdrlen;	/* media header length */
74 		u_long	ifi_mtu;	/* maximum transmission unit */
75 		u_long	ifi_metric;	/* routing metric (external only) */
76 		u_long	ifi_baudrate;	/* linespeed */
77 /* volatile statistics */
78 		u_long	ifi_ipackets;	/* packets received on interface */
79 		u_long	ifi_ierrors;	/* input errors on interface */
80 		u_long	ifi_opackets;	/* packets sent on interface */
81 		u_long	ifi_oerrors;	/* output errors on interface */
82 		u_long	ifi_collisions;	/* collisions on csma interfaces */
83 		u_long	ifi_ibytes;	/* total number of octets received */
84 		u_long	ifi_obytes;	/* total number of octets sent */
85 		u_long	ifi_imcasts;	/* packets received via multicast */
86 		u_long	ifi_omcasts;	/* packets sent via multicast */
87 		u_long	ifi_iqdrops;	/* dropped on input, this interface */
88 		u_long	ifi_noproto;	/* destined for unsupported protocol */
89 		struct	timeval ifi_lastchange;/* last updated */
90 	}	if_data;
91 /* procedure handles */
92 	int	(*if_init)		/* init routine */
93 		__P((int));
94 	int	(*if_output)		/* output routine (enqueue) */
95 		__P((struct ifnet *, struct mbuf *, struct sockaddr *,
96 		     struct rtentry *));
97 	int	(*if_start)		/* initiate output routine */
98 		__P((struct ifnet *));
99 	int	(*if_done)		/* output complete routine */
100 		__P((struct ifnet *));	/* (XXX not used; fake prototype) */
101 	int	(*if_ioctl)		/* ioctl routine */
102 		__P((struct ifnet *, int, caddr_t));
103 	int	(*if_reset)
104 		__P((int));		/* new autoconfig will permit removal */
105 	int	(*if_watchdog)		/* timer routine */
106 		__P((int));
107 	struct	ifqueue {
108 		struct	mbuf *ifq_head;
109 		struct	mbuf *ifq_tail;
110 		int	ifq_len;
111 		int	ifq_maxlen;
112 		int	ifq_drops;
113 	} if_snd;			/* output queue */
114 };
115 #define	if_mtu		if_data.ifi_mtu
116 #define	if_type		if_data.ifi_type
117 #define	if_addrlen	if_data.ifi_addrlen
118 #define	if_hdrlen	if_data.ifi_hdrlen
119 #define	if_metric	if_data.ifi_metric
120 #define	if_baudrate	if_data.ifi_baudrate
121 #define	if_ipackets	if_data.ifi_ipackets
122 #define	if_ierrors	if_data.ifi_ierrors
123 #define	if_opackets	if_data.ifi_opackets
124 #define	if_oerrors	if_data.ifi_oerrors
125 #define	if_collisions	if_data.ifi_collisions
126 #define	if_ibytes	if_data.ifi_ibytes
127 #define	if_obytes	if_data.ifi_obytes
128 #define	if_imcasts	if_data.ifi_imcasts
129 #define	if_omcasts	if_data.ifi_omcasts
130 #define	if_iqdrops	if_data.ifi_iqdrops
131 #define	if_noproto	if_data.ifi_noproto
132 #define	if_lastchange	if_data.ifi_lastchange
133 
134 #define	IFF_UP		0x1		/* interface is up */
135 #define	IFF_BROADCAST	0x2		/* broadcast address valid */
136 #define	IFF_DEBUG	0x4		/* turn on debugging */
137 #define	IFF_LOOPBACK	0x8		/* is a loopback net */
138 #define	IFF_POINTOPOINT	0x10		/* interface is point-to-point link */
139 #define	IFF_NOTRAILERS	0x20		/* avoid use of trailers */
140 #define	IFF_RUNNING	0x40		/* resources allocated */
141 #define	IFF_NOARP	0x80		/* no address resolution protocol */
142 #define	IFF_PROMISC	0x100		/* receive all packets */
143 #define	IFF_ALLMULTI	0x200		/* receive all multicast packets */
144 #define	IFF_OACTIVE	0x400		/* transmission in progress */
145 #define	IFF_SIMPLEX	0x800		/* can't hear own transmissions */
146 #define	IFF_LINK0	0x1000		/* per link layer defined bit */
147 #define	IFF_LINK1	0x2000		/* per link layer defined bit */
148 #define	IFF_LINK2	0x4000		/* per link layer defined bit */
149 #define	IFF_MULTICAST	0x8000		/* supports multicast */
150 
151 /* flags set internally only: */
152 #define	IFF_CANTCHANGE \
153 	(IFF_BROADCAST|IFF_POINTOPOINT|IFF_RUNNING|IFF_OACTIVE|\
154 	    IFF_SIMPLEX|IFF_MULTICAST)
155 
156 /*
157  * Output queues (ifp->if_snd) and internetwork datagram level (pup level 1)
158  * input routines have queues of messages stored on ifqueue structures
159  * (defined above).  Entries are added to and deleted from these structures
160  * by these macros, which should be called with ipl raised to splimp().
161  */
162 #define	IF_QFULL(ifq)		((ifq)->ifq_len >= (ifq)->ifq_maxlen)
163 #define	IF_DROP(ifq)		((ifq)->ifq_drops++)
164 #define	IF_ENQUEUE(ifq, m) { \
165 	(m)->m_nextpkt = 0; \
166 	if ((ifq)->ifq_tail == 0) \
167 		(ifq)->ifq_head = m; \
168 	else \
169 		(ifq)->ifq_tail->m_nextpkt = m; \
170 	(ifq)->ifq_tail = m; \
171 	(ifq)->ifq_len++; \
172 }
173 #define	IF_PREPEND(ifq, m) { \
174 	(m)->m_nextpkt = (ifq)->ifq_head; \
175 	if ((ifq)->ifq_tail == 0) \
176 		(ifq)->ifq_tail = (m); \
177 	(ifq)->ifq_head = (m); \
178 	(ifq)->ifq_len++; \
179 }
180 #define	IF_DEQUEUE(ifq, m) { \
181 	(m) = (ifq)->ifq_head; \
182 	if (m) { \
183 		if (((ifq)->ifq_head = (m)->m_nextpkt) == 0) \
184 			(ifq)->ifq_tail = 0; \
185 		(m)->m_nextpkt = 0; \
186 		(ifq)->ifq_len--; \
187 	} \
188 }
189 
190 #define	IFQ_MAXLEN	50
191 #define	IFNET_SLOWHZ	1		/* granularity is 1 second */
192 
193 /*
194  * The ifaddr structure contains information about one address
195  * of an interface.  They are maintained by the different address families,
196  * are allocated and attached when an address is set, and are linked
197  * together so all addresses for an interface can be located.
198  */
199 struct ifaddr {
200 	struct	sockaddr *ifa_addr;	/* address of interface */
201 	struct	sockaddr *ifa_dstaddr;	/* other end of p-to-p link */
202 #define	ifa_broadaddr	ifa_dstaddr	/* broadcast address interface */
203 	struct	sockaddr *ifa_netmask;	/* used to determine subnet */
204 	struct	ifnet *ifa_ifp;		/* back-pointer to interface */
205 	struct	ifaddr *ifa_next;	/* next address for interface */
206 	void	(*ifa_rtrequest)();	/* check or clean routes (+ or -)'d */
207 	u_short	ifa_flags;		/* mostly rt_flags for cloning */
208 	short	ifa_refcnt;		/* extra to malloc for link info */
209 	int	ifa_metric;		/* cost of going out this interface */
210 #ifdef notdef
211 	struct	rtentry *ifa_rt;	/* XXXX for ROUTETOIF ????? */
212 #endif
213 };
214 #define	IFA_ROUTE	RTF_UP		/* route installed */
215 
216 /*
217  * Message format for use in obtaining information about interfaces
218  * from getkerninfo and the routing socket
219  */
220 struct if_msghdr {
221 	u_short	ifm_msglen;	/* to skip over non-understood messages */
222 	u_char	ifm_version;	/* future binary compatability */
223 	u_char	ifm_type;	/* message type */
224 	int	ifm_addrs;	/* like rtm_addrs */
225 	int	ifm_flags;	/* value of if_flags */
226 	u_short	ifm_index;	/* index for associated ifp */
227 	struct	if_data ifm_data;/* statistics and other data about if */
228 };
229 
230 /*
231  * Message format for use in obtaining information about interface addresses
232  * from getkerninfo and the routing socket
233  */
234 struct ifa_msghdr {
235 	u_short	ifam_msglen;	/* to skip over non-understood messages */
236 	u_char	ifam_version;	/* future binary compatability */
237 	u_char	ifam_type;	/* message type */
238 	int	ifam_addrs;	/* like rtm_addrs */
239 	int	ifam_flags;	/* value of ifa_flags */
240 	u_short	ifam_index;	/* index for associated ifp */
241 	int	ifam_metric;	/* value of ifa_metric */
242 };
243 
244 /*
245  * Interface request structure used for socket
246  * ioctl's.  All interface ioctl's must have parameter
247  * definitions which begin with ifr_name.  The
248  * remainder may be interface specific.
249  */
250 struct	ifreq {
251 #define	IFNAMSIZ	16
252 	char	ifr_name[IFNAMSIZ];		/* if name, e.g. "en0" */
253 	union {
254 		struct	sockaddr ifru_addr;
255 		struct	sockaddr ifru_dstaddr;
256 		struct	sockaddr ifru_broadaddr;
257 		short	ifru_flags;
258 		int	ifru_metric;
259 		caddr_t	ifru_data;
260 	} ifr_ifru;
261 #define	ifr_addr	ifr_ifru.ifru_addr	/* address */
262 #define	ifr_dstaddr	ifr_ifru.ifru_dstaddr	/* other end of p-to-p link */
263 #define	ifr_broadaddr	ifr_ifru.ifru_broadaddr	/* broadcast address */
264 #define	ifr_flags	ifr_ifru.ifru_flags	/* flags */
265 #define	ifr_metric	ifr_ifru.ifru_metric	/* metric */
266 #define	ifr_data	ifr_ifru.ifru_data	/* for use by interface */
267 };
268 
269 struct ifaliasreq {
270 	char	ifra_name[IFNAMSIZ];		/* if name, e.g. "en0" */
271 	struct	sockaddr ifra_addr;
272 	struct	sockaddr ifra_broadaddr;
273 	struct	sockaddr ifra_mask;
274 };
275 
276 /*
277  * Structure used in SIOCGIFCONF request.
278  * Used to retrieve interface configuration
279  * for machine (useful for programs which
280  * must know all networks accessible).
281  */
282 struct	ifconf {
283 	int	ifc_len;		/* size of associated buffer */
284 	union {
285 		caddr_t	ifcu_buf;
286 		struct	ifreq *ifcu_req;
287 	} ifc_ifcu;
288 #define	ifc_buf	ifc_ifcu.ifcu_buf	/* buffer address */
289 #define	ifc_req	ifc_ifcu.ifcu_req	/* array of structures returned */
290 };
291 
292 #ifdef KERNEL
293 #define	IFAFREE(ifa) \
294 	if ((ifa)->ifa_refcnt <= 0) \
295 		ifafree(ifa); \
296 	else \
297 		(ifa)->ifa_refcnt--;
298 
299 #include "../net/if_arp.h"
300 struct	ifnet	*ifnet;
301 struct	ifaddr	*ifa_ifwithaddr __P((struct sockaddr *)),
302 		*ifa_ifwithnet __P((struct sockaddr *)),
303 		*ifa_ifwithdstaddr __P((struct sockaddr *));
304 void	ifafree __P((struct ifaddr *));
305 void	if_attach __P((struct ifnet *));
306 #else KERNEL
307 #include <net/if_arp.h>
308 #endif KERNEL
309