xref: /csrg-svn/sys/net/if.h (revision 52269)
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	7.14 (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 /*
43  * Structure defining a queue for a network interface.
44  *
45  * (Would like to call this struct ``if'', but C isn't PL/1.)
46  */
47 
48 struct ifnet {
49 	char	*if_name;		/* name, e.g. ``en'' or ``lo'' */
50 	short	if_unit;		/* sub-unit for lower level driver */
51 	short	if_mtu;			/* maximum transmission unit */
52 	short	if_flags;		/* up/down, broadcast, etc. */
53 	short	if_timer;		/* time 'til if_watchdog called */
54 	int	if_metric;		/* routing metric (external only) */
55 	struct	ifaddr *if_addrlist;	/* linked list of addresses per if */
56 	struct	ifqueue {
57 		struct	mbuf *ifq_head;
58 		struct	mbuf *ifq_tail;
59 		int	ifq_len;
60 		int	ifq_maxlen;
61 		int	ifq_drops;
62 	} if_snd;			/* output queue */
63 /* procedure handles */
64 	int	(*if_init)		/* init routine */
65 		__P((int));
66 	int	(*if_output)		/* output routine (enqueue) */
67 		__P((struct ifnet *, struct mbuf *, struct sockaddr *,
68 		     struct rtentry *));
69 	int	(*if_start)		/* initiate output routine */
70 		__P((struct ifnet *));
71 	int	(*if_done)		/* output complete routine */
72 		__P((struct ifnet *));	/* (XXX not used; fake prototype) */
73 	int	(*if_ioctl)		/* ioctl routine */
74 		__P((struct ifnet *, int, caddr_t));
75 	int	(*if_reset)		/* XXX; Unibus reset routine for vax */
76 		__P((int, int));	/* new autoconfig will permit removal */
77 	int	(*if_watchdog)		/* timer routine */
78 		__P((int));
79 /* generic interface statistics */
80 	int	if_ipackets;		/* packets received on interface */
81 	int	if_ierrors;		/* input errors on interface */
82 	int	if_opackets;		/* packets sent on interface */
83 	int	if_oerrors;		/* output errors on interface */
84 	int	if_collisions;		/* collisions on csma interfaces */
85 /* end statistics */
86 	struct	ifnet *if_next;
87 	u_char	if_type;		/* ethernet, tokenring, etc */
88 	u_char	if_addrlen;		/* media address length */
89 	u_char	if_hdrlen;		/* media header length */
90 	u_char	if_index;		/* numeric abbreviation for this if  */
91 /* more statistics here to avoid recompiling netstat */
92 	struct	timeval if_lastchange;	/* last updated */
93 	int	if_ibytes;		/* total number of octets received */
94 	int	if_obytes;		/* total number of octets sent */
95 	int	if_imcasts;		/* packets received via multicast */
96 	int	if_omcasts;		/* packets sent via multicast */
97 	int	if_iqdrops;		/* dropped on input, this interface */
98 	int	if_noproto;		/* destined for unsupported protocol */
99 	int	if_baudrate;		/* linespeed */
100         int	if_pcount;		/* number of promiscuous listeners */
101 };
102 
103 #define	IFF_UP		0x1		/* interface is up */
104 #define	IFF_BROADCAST	0x2		/* broadcast address valid */
105 #define	IFF_DEBUG	0x4		/* turn on debugging */
106 #define	IFF_LOOPBACK	0x8		/* is a loopback net */
107 #define	IFF_POINTOPOINT	0x10		/* interface is point-to-point link */
108 #define	IFF_NOTRAILERS	0x20		/* avoid use of trailers */
109 #define	IFF_RUNNING	0x40		/* resources allocated */
110 #define	IFF_NOARP	0x80		/* no address resolution protocol */
111 /* next two not supported now, but reserved: */
112 #define	IFF_PROMISC	0x100		/* receive all packets */
113 #define	IFF_ALLMULTI	0x200		/* receive all multicast packets */
114 #define	IFF_OACTIVE	0x400		/* transmission in progress */
115 #define	IFF_SIMPLEX	0x800		/* can't hear own transmissions */
116 #define	IFF_LINK0	0x1000		/* per link layer defined bit */
117 #define	IFF_LINK1	0x2000		/* per link layer defined bit */
118 #define	IFF_LINK2	0x4000		/* per link layer defined bit */
119 
120 /* flags set internally only: */
121 #define	IFF_CANTCHANGE \
122 	(IFF_BROADCAST|IFF_POINTOPOINT|IFF_RUNNING|IFF_OACTIVE|IFF_SIMPLEX)
123 
124 /*
125  * Output queues (ifp->if_snd) and internetwork datagram level (pup level 1)
126  * input routines have queues of messages stored on ifqueue structures
127  * (defined above).  Entries are added to and deleted from these structures
128  * by these macros, which should be called with ipl raised to splimp().
129  */
130 #define	IF_QFULL(ifq)		((ifq)->ifq_len >= (ifq)->ifq_maxlen)
131 #define	IF_DROP(ifq)		((ifq)->ifq_drops++)
132 #define	IF_ENQUEUE(ifq, m) { \
133 	(m)->m_nextpkt = 0; \
134 	if ((ifq)->ifq_tail == 0) \
135 		(ifq)->ifq_head = m; \
136 	else \
137 		(ifq)->ifq_tail->m_nextpkt = m; \
138 	(ifq)->ifq_tail = m; \
139 	(ifq)->ifq_len++; \
140 }
141 #define	IF_PREPEND(ifq, m) { \
142 	(m)->m_nextpkt = (ifq)->ifq_head; \
143 	if ((ifq)->ifq_tail == 0) \
144 		(ifq)->ifq_tail = (m); \
145 	(ifq)->ifq_head = (m); \
146 	(ifq)->ifq_len++; \
147 }
148 #define	IF_DEQUEUE(ifq, m) { \
149 	(m) = (ifq)->ifq_head; \
150 	if (m) { \
151 		if (((ifq)->ifq_head = (m)->m_nextpkt) == 0) \
152 			(ifq)->ifq_tail = 0; \
153 		(m)->m_nextpkt = 0; \
154 		(ifq)->ifq_len--; \
155 	} \
156 }
157 
158 #define	IFQ_MAXLEN	50
159 #define	IFNET_SLOWHZ	1		/* granularity is 1 second */
160 
161 /*
162  * The ifaddr structure contains information about one address
163  * of an interface.  They are maintained by the different address families,
164  * are allocated and attached when an address is set, and are linked
165  * together so all addresses for an interface can be located.
166  */
167 struct ifaddr {
168 	struct	sockaddr *ifa_addr;	/* address of interface */
169 	struct	sockaddr *ifa_dstaddr;	/* other end of p-to-p link */
170 #define	ifa_broadaddr	ifa_dstaddr	/* broadcast address interface */
171 	struct	sockaddr *ifa_netmask;	/* used to determine subnet */
172 	struct	ifnet *ifa_ifp;		/* back-pointer to interface */
173 	struct	ifaddr *ifa_next;	/* next address for interface */
174 	int	(*ifa_rtrequest)();	/* check or clean routes (+ or -)'d */
175 	struct 	rtentry *ifa_rt;	/* ??? for ROUTETOIF */
176 	u_short	ifa_flags;		/* mostly rt_flags for cloning */
177 	short	ifa_refcnt;		/* extra to malloc for link info */
178 };
179 #define IFA_ROUTE	RTF_UP		/* route installed */
180 /*
181  * Interface request structure used for socket
182  * ioctl's.  All interface ioctl's must have parameter
183  * definitions which begin with ifr_name.  The
184  * remainder may be interface specific.
185  */
186 struct	ifreq {
187 #define	IFNAMSIZ	16
188 	char	ifr_name[IFNAMSIZ];		/* if name, e.g. "en0" */
189 	union {
190 		struct	sockaddr ifru_addr;
191 		struct	sockaddr ifru_dstaddr;
192 		struct	sockaddr ifru_broadaddr;
193 		short	ifru_flags;
194 		int	ifru_metric;
195 		caddr_t	ifru_data;
196 	} ifr_ifru;
197 #define	ifr_addr	ifr_ifru.ifru_addr	/* address */
198 #define	ifr_dstaddr	ifr_ifru.ifru_dstaddr	/* other end of p-to-p link */
199 #define	ifr_broadaddr	ifr_ifru.ifru_broadaddr	/* broadcast address */
200 #define	ifr_flags	ifr_ifru.ifru_flags	/* flags */
201 #define	ifr_metric	ifr_ifru.ifru_metric	/* metric */
202 #define	ifr_data	ifr_ifru.ifru_data	/* for use by interface */
203 };
204 
205 struct ifaliasreq {
206 	char	ifra_name[IFNAMSIZ];		/* if name, e.g. "en0" */
207 	struct	sockaddr ifra_addr;
208 	struct	sockaddr ifra_broadaddr;
209 	struct	sockaddr ifra_mask;
210 };
211 
212 /*
213  * Structure used in SIOCGIFCONF request.
214  * Used to retrieve interface configuration
215  * for machine (useful for programs which
216  * must know all networks accessible).
217  */
218 struct	ifconf {
219 	int	ifc_len;		/* size of associated buffer */
220 	union {
221 		caddr_t	ifcu_buf;
222 		struct	ifreq *ifcu_req;
223 	} ifc_ifcu;
224 #define	ifc_buf	ifc_ifcu.ifcu_buf	/* buffer address */
225 #define	ifc_req	ifc_ifcu.ifcu_req	/* array of structures returned */
226 };
227 
228 #ifdef KERNEL
229 #define	IFAFREE(ifa) \
230 	if ((ifa)->ifa_refcnt <= 0) \
231 		ifafree(ifa); \
232 	else \
233 		(ifa)->ifa_refcnt--;
234 
235 #include "../net/if_arp.h"
236 struct	ifqueue rawintrq;		/* raw packet input queue */
237 struct	ifnet	*ifnet;
238 struct	ifaddr	*ifa_ifwithaddr __P((struct sockaddr *)),
239 		*ifa_ifwithnet __P((struct sockaddr *)),
240 		*ifa_ifwithdstaddr __P((struct sockaddr *));
241 void	ifafree __P((struct ifaddr *));
242 void	if_attach __P((struct ifnet *));
243 #else KERNEL
244 #include <net/if_arp.h>
245 #endif KERNEL
246