xref: /original-bsd/sys/net/if.h (revision a94793f7)
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	7.11 (Berkeley) 03/19/91
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)
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 	int	(*if_output)();		/* output routine (enqueue) */
66 	int	(*if_start)();		/* initiate output routine */
67 	int	(*if_done)();		/* output complete 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 	u_char	if_type;		/* ethernet, tokenring, etc */
80 	u_char	if_addrlen;		/* media address length */
81 	u_char	if_hdrlen;		/* media header length */
82 	u_char	if_index;		/* numeric abbreviation for this if  */
83 /* more statistics here to avoid recompiling netstat */
84 	struct	timeval if_lastchange;	/* last updated */
85 	int	if_ibytes;		/* total number of octets received */
86 	int	if_obytes;		/* total number of octets sent */
87 	int	if_imcasts;		/* packets received via multicast */
88 	int	if_omcasts;		/* packets sent via multicast */
89 	int	if_iqdrops;		/* dropped on input, this interface */
90 	int	if_noproto;		/* destined for unsupported protocol */
91 	int	if_baudrate;		/* linespeed */
92         int	if_pcount;		/* number of promiscuous listeners */
93 };
94 
95 #define	IFF_UP		0x1		/* interface is up */
96 #define	IFF_BROADCAST	0x2		/* broadcast address valid */
97 #define	IFF_DEBUG	0x4		/* turn on debugging */
98 #define	IFF_LOOPBACK	0x8		/* is a loopback net */
99 #define	IFF_POINTOPOINT	0x10		/* interface is point-to-point link */
100 #define	IFF_NOTRAILERS	0x20		/* avoid use of trailers */
101 #define	IFF_RUNNING	0x40		/* resources allocated */
102 #define	IFF_NOARP	0x80		/* no address resolution protocol */
103 /* next two not supported now, but reserved: */
104 #define	IFF_PROMISC	0x100		/* receive all packets */
105 #define	IFF_ALLMULTI	0x200		/* receive all multicast packets */
106 #define	IFF_OACTIVE	0x400		/* transmission in progress */
107 #define	IFF_SIMPLEX	0x800		/* can't hear own transmissions */
108 
109 /* flags set internally only: */
110 #define	IFF_CANTCHANGE \
111 	(IFF_BROADCAST|IFF_POINTOPOINT|IFF_RUNNING|IFF_OACTIVE|IFF_SIMPLEX)
112 
113 /*
114  * Output queues (ifp->if_snd) and internetwork datagram level (pup level 1)
115  * input routines have queues of messages stored on ifqueue structures
116  * (defined above).  Entries are added to and deleted from these structures
117  * by these macros, which should be called with ipl raised to splimp().
118  */
119 #define	IF_QFULL(ifq)		((ifq)->ifq_len >= (ifq)->ifq_maxlen)
120 #define	IF_DROP(ifq)		((ifq)->ifq_drops++)
121 #define	IF_ENQUEUE(ifq, m) { \
122 	(m)->m_nextpkt = 0; \
123 	if ((ifq)->ifq_tail == 0) \
124 		(ifq)->ifq_head = m; \
125 	else \
126 		(ifq)->ifq_tail->m_nextpkt = m; \
127 	(ifq)->ifq_tail = m; \
128 	(ifq)->ifq_len++; \
129 }
130 #define	IF_PREPEND(ifq, m) { \
131 	(m)->m_nextpkt = (ifq)->ifq_head; \
132 	if ((ifq)->ifq_tail == 0) \
133 		(ifq)->ifq_tail = (m); \
134 	(ifq)->ifq_head = (m); \
135 	(ifq)->ifq_len++; \
136 }
137 #define	IF_DEQUEUE(ifq, m) { \
138 	(m) = (ifq)->ifq_head; \
139 	if (m) { \
140 		if (((ifq)->ifq_head = (m)->m_nextpkt) == 0) \
141 			(ifq)->ifq_tail = 0; \
142 		(m)->m_nextpkt = 0; \
143 		(ifq)->ifq_len--; \
144 	} \
145 }
146 
147 #define	IFQ_MAXLEN	50
148 #define	IFNET_SLOWHZ	1		/* granularity is 1 second */
149 
150 /*
151  * The ifaddr structure contains information about one address
152  * of an interface.  They are maintained by the different address families,
153  * are allocated and attached when an address is set, and are linked
154  * together so all addresses for an interface can be located.
155  */
156 struct ifaddr {
157 	struct	sockaddr *ifa_addr;	/* address of interface */
158 	struct	sockaddr *ifa_dstaddr;	/* other end of p-to-p link */
159 #define	ifa_broadaddr	ifa_dstaddr	/* broadcast address interface */
160 	struct	sockaddr *ifa_netmask;	/* used to determine subnet */
161 	struct	ifnet *ifa_ifp;		/* back-pointer to interface */
162 	struct	ifaddr *ifa_next;	/* next address for interface */
163 	int	(*ifa_rtrequest)();	/* check or clean routes (+ or -)'d */
164 	struct 	rtentry *ifa_rt;	/* ??? for ROUTETOIF */
165 	u_short	ifa_flags;		/* mostly rt_flags for cloning */
166 	u_short	ifa_llinfolen;		/* extra to malloc for link info */
167 };
168 #define IFA_ROUTE	RTF_UP		/* route installed */
169 /*
170  * Interface request structure used for socket
171  * ioctl's.  All interface ioctl's must have parameter
172  * definitions which begin with ifr_name.  The
173  * remainder may be interface specific.
174  */
175 struct	ifreq {
176 #define	IFNAMSIZ	16
177 	char	ifr_name[IFNAMSIZ];		/* if name, e.g. "en0" */
178 	union {
179 		struct	sockaddr ifru_addr;
180 		struct	sockaddr ifru_dstaddr;
181 		struct	sockaddr ifru_broadaddr;
182 		short	ifru_flags;
183 		int	ifru_metric;
184 		caddr_t	ifru_data;
185 	} ifr_ifru;
186 #define	ifr_addr	ifr_ifru.ifru_addr	/* address */
187 #define	ifr_dstaddr	ifr_ifru.ifru_dstaddr	/* other end of p-to-p link */
188 #define	ifr_broadaddr	ifr_ifru.ifru_broadaddr	/* broadcast address */
189 #define	ifr_flags	ifr_ifru.ifru_flags	/* flags */
190 #define	ifr_metric	ifr_ifru.ifru_metric	/* metric */
191 #define	ifr_data	ifr_ifru.ifru_data	/* for use by interface */
192 };
193 
194 struct ifaliasreq {
195 	char	ifra_name[IFNAMSIZ];		/* if name, e.g. "en0" */
196 	struct	sockaddr ifra_addr;
197 	struct	sockaddr ifra_broadaddr;
198 	struct	sockaddr ifra_mask;
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