xref: /csrg-svn/sys/net/if.h (revision 52272)
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	7.15 (Berkeley) 01/30/92
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 #endif
48 /*
49  * Structure defining a queue for a network interface.
50  *
51  * (Would like to call this struct ``if'', but C isn't PL/1.)
52  */
53 
54 struct ifnet {
55 	char	*if_name;		/* name, e.g. ``en'' or ``lo'' */
56 	short	if_unit;		/* sub-unit for lower level driver */
57 	short	if_mtu;			/* maximum transmission unit */
58 	short	if_flags;		/* up/down, broadcast, etc. */
59 	short	if_timer;		/* time 'til if_watchdog called */
60 	int	if_metric;		/* routing metric (external only) */
61 	struct	ifaddr *if_addrlist;	/* linked list of addresses per if */
62 	struct	ifqueue {
63 		struct	mbuf *ifq_head;
64 		struct	mbuf *ifq_tail;
65 		int	ifq_len;
66 		int	ifq_maxlen;
67 		int	ifq_drops;
68 	} if_snd;			/* output queue */
69 /* procedure handles */
70 	int	(*if_init)		/* init routine */
71 		__P((int));
72 	int	(*if_output)		/* output routine (enqueue) */
73 		__P((struct ifnet *, struct mbuf *, struct sockaddr *,
74 		     struct rtentry *));
75 	int	(*if_start)		/* initiate output routine */
76 		__P((struct ifnet *));
77 	int	(*if_done)		/* output complete routine */
78 		__P((struct ifnet *));	/* (XXX not used; fake prototype) */
79 	int	(*if_ioctl)		/* ioctl routine */
80 		__P((struct ifnet *, int, caddr_t));
81 	int	(*if_reset)		/* XXX; Unibus reset routine for vax */
82 		__P((int, int));	/* new autoconfig will permit removal */
83 	int	(*if_watchdog)		/* timer routine */
84 		__P((int));
85 /* generic interface statistics */
86 	int	if_ipackets;		/* packets received on interface */
87 	int	if_ierrors;		/* input errors on interface */
88 	int	if_opackets;		/* packets sent on interface */
89 	int	if_oerrors;		/* output errors on interface */
90 	int	if_collisions;		/* collisions on csma interfaces */
91 /* end statistics */
92 	struct	ifnet *if_next;
93 	u_char	if_type;		/* ethernet, tokenring, etc */
94 	u_char	if_addrlen;		/* media address length */
95 	u_char	if_hdrlen;		/* media header length */
96 	u_char	if_index;		/* numeric abbreviation for this if  */
97 /* more statistics here to avoid recompiling netstat */
98 	struct	timeval if_lastchange;	/* last updated */
99 	int	if_ibytes;		/* total number of octets received */
100 	int	if_obytes;		/* total number of octets sent */
101 	int	if_imcasts;		/* packets received via multicast */
102 	int	if_omcasts;		/* packets sent via multicast */
103 	int	if_iqdrops;		/* dropped on input, this interface */
104 	int	if_noproto;		/* destined for unsupported protocol */
105 	int	if_baudrate;		/* linespeed */
106         int	if_pcount;		/* number of promiscuous listeners */
107 };
108 
109 #define	IFF_UP		0x1		/* interface is up */
110 #define	IFF_BROADCAST	0x2		/* broadcast address valid */
111 #define	IFF_DEBUG	0x4		/* turn on debugging */
112 #define	IFF_LOOPBACK	0x8		/* is a loopback net */
113 #define	IFF_POINTOPOINT	0x10		/* interface is point-to-point link */
114 #define	IFF_NOTRAILERS	0x20		/* avoid use of trailers */
115 #define	IFF_RUNNING	0x40		/* resources allocated */
116 #define	IFF_NOARP	0x80		/* no address resolution protocol */
117 /* next two not supported now, but reserved: */
118 #define	IFF_PROMISC	0x100		/* receive all packets */
119 #define	IFF_ALLMULTI	0x200		/* receive all multicast packets */
120 #define	IFF_OACTIVE	0x400		/* transmission in progress */
121 #define	IFF_SIMPLEX	0x800		/* can't hear own transmissions */
122 #define	IFF_LINK0	0x1000		/* per link layer defined bit */
123 #define	IFF_LINK1	0x2000		/* per link layer defined bit */
124 #define	IFF_LINK2	0x4000		/* per link layer defined bit */
125 
126 /* flags set internally only: */
127 #define	IFF_CANTCHANGE \
128 	(IFF_BROADCAST|IFF_POINTOPOINT|IFF_RUNNING|IFF_OACTIVE|IFF_SIMPLEX)
129 
130 /*
131  * Output queues (ifp->if_snd) and internetwork datagram level (pup level 1)
132  * input routines have queues of messages stored on ifqueue structures
133  * (defined above).  Entries are added to and deleted from these structures
134  * by these macros, which should be called with ipl raised to splimp().
135  */
136 #define	IF_QFULL(ifq)		((ifq)->ifq_len >= (ifq)->ifq_maxlen)
137 #define	IF_DROP(ifq)		((ifq)->ifq_drops++)
138 #define	IF_ENQUEUE(ifq, m) { \
139 	(m)->m_nextpkt = 0; \
140 	if ((ifq)->ifq_tail == 0) \
141 		(ifq)->ifq_head = m; \
142 	else \
143 		(ifq)->ifq_tail->m_nextpkt = m; \
144 	(ifq)->ifq_tail = m; \
145 	(ifq)->ifq_len++; \
146 }
147 #define	IF_PREPEND(ifq, m) { \
148 	(m)->m_nextpkt = (ifq)->ifq_head; \
149 	if ((ifq)->ifq_tail == 0) \
150 		(ifq)->ifq_tail = (m); \
151 	(ifq)->ifq_head = (m); \
152 	(ifq)->ifq_len++; \
153 }
154 #define	IF_DEQUEUE(ifq, m) { \
155 	(m) = (ifq)->ifq_head; \
156 	if (m) { \
157 		if (((ifq)->ifq_head = (m)->m_nextpkt) == 0) \
158 			(ifq)->ifq_tail = 0; \
159 		(m)->m_nextpkt = 0; \
160 		(ifq)->ifq_len--; \
161 	} \
162 }
163 
164 #define	IFQ_MAXLEN	50
165 #define	IFNET_SLOWHZ	1		/* granularity is 1 second */
166 
167 /*
168  * The ifaddr structure contains information about one address
169  * of an interface.  They are maintained by the different address families,
170  * are allocated and attached when an address is set, and are linked
171  * together so all addresses for an interface can be located.
172  */
173 struct ifaddr {
174 	struct	sockaddr *ifa_addr;	/* address of interface */
175 	struct	sockaddr *ifa_dstaddr;	/* other end of p-to-p link */
176 #define	ifa_broadaddr	ifa_dstaddr	/* broadcast address interface */
177 	struct	sockaddr *ifa_netmask;	/* used to determine subnet */
178 	struct	ifnet *ifa_ifp;		/* back-pointer to interface */
179 	struct	ifaddr *ifa_next;	/* next address for interface */
180 	int	(*ifa_rtrequest)();	/* check or clean routes (+ or -)'d */
181 	struct 	rtentry *ifa_rt;	/* ??? for ROUTETOIF */
182 	u_short	ifa_flags;		/* mostly rt_flags for cloning */
183 	short	ifa_refcnt;		/* extra to malloc for link info */
184 };
185 #define IFA_ROUTE	RTF_UP		/* route installed */
186 /*
187  * Interface request structure used for socket
188  * ioctl's.  All interface ioctl's must have parameter
189  * definitions which begin with ifr_name.  The
190  * remainder may be interface specific.
191  */
192 struct	ifreq {
193 #define	IFNAMSIZ	16
194 	char	ifr_name[IFNAMSIZ];		/* if name, e.g. "en0" */
195 	union {
196 		struct	sockaddr ifru_addr;
197 		struct	sockaddr ifru_dstaddr;
198 		struct	sockaddr ifru_broadaddr;
199 		short	ifru_flags;
200 		int	ifru_metric;
201 		caddr_t	ifru_data;
202 	} ifr_ifru;
203 #define	ifr_addr	ifr_ifru.ifru_addr	/* address */
204 #define	ifr_dstaddr	ifr_ifru.ifru_dstaddr	/* other end of p-to-p link */
205 #define	ifr_broadaddr	ifr_ifru.ifru_broadaddr	/* broadcast address */
206 #define	ifr_flags	ifr_ifru.ifru_flags	/* flags */
207 #define	ifr_metric	ifr_ifru.ifru_metric	/* metric */
208 #define	ifr_data	ifr_ifru.ifru_data	/* for use by interface */
209 };
210 
211 struct ifaliasreq {
212 	char	ifra_name[IFNAMSIZ];		/* if name, e.g. "en0" */
213 	struct	sockaddr ifra_addr;
214 	struct	sockaddr ifra_broadaddr;
215 	struct	sockaddr ifra_mask;
216 };
217 
218 /*
219  * Structure used in SIOCGIFCONF request.
220  * Used to retrieve interface configuration
221  * for machine (useful for programs which
222  * must know all networks accessible).
223  */
224 struct	ifconf {
225 	int	ifc_len;		/* size of associated buffer */
226 	union {
227 		caddr_t	ifcu_buf;
228 		struct	ifreq *ifcu_req;
229 	} ifc_ifcu;
230 #define	ifc_buf	ifc_ifcu.ifcu_buf	/* buffer address */
231 #define	ifc_req	ifc_ifcu.ifcu_req	/* array of structures returned */
232 };
233 
234 #ifdef KERNEL
235 #define	IFAFREE(ifa) \
236 	if ((ifa)->ifa_refcnt <= 0) \
237 		ifafree(ifa); \
238 	else \
239 		(ifa)->ifa_refcnt--;
240 
241 #include "../net/if_arp.h"
242 struct	ifqueue rawintrq;		/* raw packet input queue */
243 struct	ifnet	*ifnet;
244 struct	ifaddr	*ifa_ifwithaddr __P((struct sockaddr *)),
245 		*ifa_ifwithnet __P((struct sockaddr *)),
246 		*ifa_ifwithdstaddr __P((struct sockaddr *));
247 void	ifafree __P((struct ifaddr *));
248 void	if_attach __P((struct ifnet *));
249 #else KERNEL
250 #include <net/if_arp.h>
251 #endif KERNEL
252