source: rtems/c/src/exec/libnetworking/net/if.h @ a3d0b8a

4.104.114.84.9
Last change on this file since a3d0b8a was a3d0b8a, checked in by Joel Sherrill <joel.sherrill@…>, on Dec 10, 1998 at 7:42:29 PM

Patch from Ian Lance Taylor <ian@…>:

From: Eric Norum <eric@…>
Date: Sat, 5 Dec 98 13:20:51 -0600

What do you think of this patch? It implements your `tap'
suggestion in a way that adds support for all ethernet devices with
no driver modifications. I also added a return value from the tap
function. If the return value is zero, the packet will be passed up
the chain as usual. If the return value is non-zero the mbuf holding
the packet will be freed and the packet will be dropped.

If you like it, please submit it to Joel.

I guess there needs to be an addition to the network documentation
describing the additional ioctl's -- and a big warning that the tap
function is called from a context that holds the network semaphore.

Here is Eric's patch. I've tested it a bit, and made a couple of
trivial changes. This is certainly better than mine: it should work
for all Ethernet drivers.
==================================================

The only concern I have about this patch is that the tap function may
want to fiddle with the mbuf, calling functions like m_pullup and the
like. If those force the networking code to rearrange the mbuf
structure, then the caller's call to m_freem may crash. I don't know
if this is a realistic concern--I don't know enough about the mbuf
layer.

  • Property mode set to 100644
File size: 16.4 KB
Line 
1/*
2 * Copyright (c) 1982, 1986, 1989, 1993
3 *      The Regents of the University of California.  All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 * 3. All advertising materials mentioning features or use of this software
14 *    must display the following acknowledgement:
15 *      This product includes software developed by the University of
16 *      California, Berkeley and its contributors.
17 * 4. Neither the name of the University nor the names of its contributors
18 *    may be used to endorse or promote products derived from this software
19 *    without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * SUCH DAMAGE.
32 *
33 *      @(#)if.h        8.1 (Berkeley) 6/10/93
34 * $Id$
35 */
36
37#ifndef _NET_IF_H_
38#define _NET_IF_H_
39
40/*
41 * Structures defining a network interface, providing a packet
42 * transport mechanism (ala level 0 of the PUP protocols).
43 *
44 * Each interface accepts output datagrams of a specified maximum
45 * length, and provides higher level routines with input datagrams
46 * received from its medium.
47 *
48 * Output occurs when the routine if_output is called, with three parameters:
49 *      (*ifp->if_output)(ifp, m, dst, rt)
50 * Here m is the mbuf chain to be sent and dst is the destination address.
51 * The output routine encapsulates the supplied datagram if necessary,
52 * and then transmits it on its medium.
53 *
54 * On input, each interface unwraps the data received by it, and either
55 * places it on the input queue of a internetwork datagram routine
56 * and posts the associated software interrupt, or passes the datagram to a raw
57 * packet input routine.
58 *
59 * Routines exist for locating interfaces by their addresses
60 * or for locating a interface on a certain network, as well as more general
61 * routing and gateway routines maintaining information used to locate
62 * interfaces.  These routines live in the files if.c and route.c
63 */
64
65#ifndef _TIME_ /*  XXX fast fix for SNMP, going away soon */
66#include <sys/time.h>
67#endif
68
69#ifdef __STDC__
70/*
71 * Forward structure declarations for function prototypes [sic].
72 */
73struct  mbuf;
74struct  proc;
75struct  rtentry;
76struct  socket;
77struct  ether_header;
78#endif
79
80/*
81 * Structure describing information about an interface
82 * which may be of interest to management entities.
83 */
84struct if_data {
85        /* generic interface information */
86        u_char  ifi_type;               /* ethernet, tokenring, etc */
87        u_char  ifi_physical;           /* e.g., AUI, Thinnet, 10base-T, etc */
88        u_char  ifi_addrlen;            /* media address length */
89        u_char  ifi_hdrlen;             /* media header length */
90        u_char  ifi_recvquota;          /* polling quota for receive intrs */
91        u_char  ifi_xmitquota;          /* polling quota for xmit intrs */
92        u_long  ifi_mtu;                /* maximum transmission unit */
93        u_long  ifi_metric;             /* routing metric (external only) */
94        u_long  ifi_baudrate;           /* linespeed */
95        /* volatile statistics */
96        u_long  ifi_ipackets;           /* packets received on interface */
97        u_long  ifi_ierrors;            /* input errors on interface */
98        u_long  ifi_opackets;           /* packets sent on interface */
99        u_long  ifi_oerrors;            /* output errors on interface */
100        u_long  ifi_collisions;         /* collisions on csma interfaces */
101        u_long  ifi_ibytes;             /* total number of octets received */
102        u_long  ifi_obytes;             /* total number of octets sent */
103        u_long  ifi_imcasts;            /* packets received via multicast */
104        u_long  ifi_omcasts;            /* packets sent via multicast */
105        u_long  ifi_iqdrops;            /* dropped on input, this interface */
106        u_long  ifi_noproto;            /* destined for unsupported protocol */
107        u_long  ifi_recvtiming;         /* usec spent receiving when timing */
108        u_long  ifi_xmittiming;         /* usec spent xmitting when timing */
109        struct  timeval ifi_lastchange; /* time of last administrative change */
110};
111
112/*
113 * Structure defining a queue for a network interface.
114 */
115struct  ifqueue {
116        struct  mbuf *ifq_head;
117        struct  mbuf *ifq_tail;
118        int     ifq_len;
119        int     ifq_maxlen;
120        int     ifq_drops;
121};
122
123/*
124 * Structure defining a network interface.
125 *
126 * (Would like to call this struct ``if'', but C isn't PL/1.)
127 */
128struct ifnet {
129        void    *if_softc;              /* pointer to driver state */
130        char    *if_name;               /* name, e.g. ``en'' or ``lo'' */
131        struct  ifnet *if_next;         /* all struct ifnets are chained */
132        struct  ifaddr *if_addrlist;    /* linked list of addresses per if */
133        int     if_pcount;              /* number of promiscuous listeners */
134        struct  bpf_if *if_bpf;         /* packet filter structure */
135        u_short if_index;               /* numeric abbreviation for this if  */
136        short   if_unit;                /* sub-unit for lower level driver */
137        short   if_timer;               /* time 'til if_watchdog called */
138        short   if_flags;               /* up/down, broadcast, etc. */
139        int     if_ipending;            /* interrupts pending */
140        void    *if_linkmib;            /* link-type-specific MIB data */
141        size_t  if_linkmiblen;          /* length of above data */
142        struct  if_data if_data;
143/* procedure handles */
144        int     (*if_output)            /* output routine (enqueue) */
145                __P((struct ifnet *, struct mbuf *, struct sockaddr *,
146                     struct rtentry *));
147        void    (*if_start)             /* initiate output routine */
148                __P((struct ifnet *));
149        int     (*if_done)              /* output complete routine */
150                __P((struct ifnet *));  /* (XXX not used; fake prototype) */
151        int     (*if_ioctl)             /* ioctl routine */
152                __P((struct ifnet *, int, caddr_t));
153        void    (*if_watchdog)          /* timer routine */
154                __P((struct ifnet *));
155        int     (*if_poll_recv)         /* polled receive routine */
156                __P((struct ifnet *, int *));
157        int     (*if_poll_xmit)         /* polled transmit routine */
158                __P((struct ifnet *, int *));
159        void    (*if_poll_intren)       /* polled interrupt reenable routine */
160                __P((struct ifnet *));
161        void    (*if_poll_slowinput)    /* input routine for slow devices */
162                __P((struct ifnet *, struct mbuf *));
163        void    (*if_init)              /* Init routine */
164                __P((void *));
165        int     (*if_tap)               /* Packet filter routine */
166                (struct ifnet *, struct ether_header *, struct mbuf *);
167        struct  ifqueue if_snd;         /* output queue */
168        struct  ifqueue *if_poll_slowq; /* input queue for slow devices */
169};
170typedef void if_init_f_t __P((void *));       
171
172#define if_mtu          if_data.ifi_mtu
173#define if_type         if_data.ifi_type
174#define if_physical     if_data.ifi_physical
175#define if_addrlen      if_data.ifi_addrlen
176#define if_hdrlen       if_data.ifi_hdrlen
177#define if_metric       if_data.ifi_metric
178#define if_baudrate     if_data.ifi_baudrate
179#define if_ipackets     if_data.ifi_ipackets
180#define if_ierrors      if_data.ifi_ierrors
181#define if_opackets     if_data.ifi_opackets
182#define if_oerrors      if_data.ifi_oerrors
183#define if_collisions   if_data.ifi_collisions
184#define if_ibytes       if_data.ifi_ibytes
185#define if_obytes       if_data.ifi_obytes
186#define if_imcasts      if_data.ifi_imcasts
187#define if_omcasts      if_data.ifi_omcasts
188#define if_iqdrops      if_data.ifi_iqdrops
189#define if_noproto      if_data.ifi_noproto
190#define if_lastchange   if_data.ifi_lastchange
191#define if_recvquota    if_data.ifi_recvquota
192#define if_xmitquota    if_data.ifi_xmitquota
193#define if_rawoutput(if, m, sa) if_output(if, m, sa, (struct rtentry *)0)
194
195#define IFF_UP          0x1             /* interface is up */
196#define IFF_BROADCAST   0x2             /* broadcast address valid */
197#define IFF_DEBUG       0x4             /* turn on debugging */
198#define IFF_LOOPBACK    0x8             /* is a loopback net */
199#define IFF_POINTOPOINT 0x10            /* interface is point-to-point link */
200/*#define IFF_NOTRAILERS 0x20            * obsolete: avoid use of trailers */
201#define IFF_RUNNING     0x40            /* resources allocated */
202#define IFF_NOARP       0x80            /* no address resolution protocol */
203#define IFF_PROMISC     0x100           /* receive all packets */
204#define IFF_ALLMULTI    0x200           /* receive all multicast packets */
205#define IFF_OACTIVE     0x400           /* transmission in progress */
206#define IFF_SIMPLEX     0x800           /* can't hear own transmissions */
207#define IFF_LINK0       0x1000          /* per link layer defined bit */
208#define IFF_LINK1       0x2000          /* per link layer defined bit */
209#define IFF_LINK2       0x4000          /* per link layer defined bit */
210#define IFF_ALTPHYS     IFF_LINK2       /* use alternate physical connection */
211#define IFF_MULTICAST   0x8000          /* supports multicast */
212
213/* flags set internally only: */
214#define IFF_CANTCHANGE \
215        (IFF_BROADCAST|IFF_POINTOPOINT|IFF_RUNNING|IFF_OACTIVE|\
216            IFF_SIMPLEX|IFF_MULTICAST|IFF_ALLMULTI)
217
218
219/*
220 * These really don't belong here, but there's no other obviously appropriate
221 * location.
222 */
223#define IFP_AUI         0
224#define IFP_10BASE2     1
225#define IFP_10BASET     2
226/* etc. */
227
228/*
229 * Bit values in if_ipending
230 */
231#define IFI_RECV        1       /* I want to receive */
232#define IFI_XMIT        2       /* I want to transmit */
233
234/*
235 * Output queues (ifp->if_snd) and slow device input queues (*ifp->if_slowq)
236 * are queues of messages stored on ifqueue structures
237 * (defined above).  Entries are added to and deleted from these structures
238 * by these macros, which should be called with ipl raised to splimp().
239 */
240#define IF_QFULL(ifq)           ((ifq)->ifq_len >= (ifq)->ifq_maxlen)
241#define IF_DROP(ifq)            ((ifq)->ifq_drops++)
242#define IF_ENQUEUE(ifq, m) { \
243        (m)->m_nextpkt = 0; \
244        if ((ifq)->ifq_tail == 0) \
245                (ifq)->ifq_head = m; \
246        else \
247                (ifq)->ifq_tail->m_nextpkt = m; \
248        (ifq)->ifq_tail = m; \
249        (ifq)->ifq_len++; \
250}
251#define IF_PREPEND(ifq, m) { \
252        (m)->m_nextpkt = (ifq)->ifq_head; \
253        if ((ifq)->ifq_tail == 0) \
254                (ifq)->ifq_tail = (m); \
255        (ifq)->ifq_head = (m); \
256        (ifq)->ifq_len++; \
257}
258#define IF_DEQUEUE(ifq, m) { \
259        (m) = (ifq)->ifq_head; \
260        if (m) { \
261                if (((ifq)->ifq_head = (m)->m_nextpkt) == 0) \
262                        (ifq)->ifq_tail = 0; \
263                (m)->m_nextpkt = 0; \
264                (ifq)->ifq_len--; \
265        } \
266}
267
268#ifdef KERNEL
269#define IF_ENQ_DROP(ifq, m)     if_enq_drop(ifq, m)
270
271#if defined(__GNUC__) && defined(MT_HEADER)
272static inline int
273if_queue_drop(struct ifqueue *ifq, struct mbuf *m)
274{
275        IF_DROP(ifq);
276        return 0;
277}
278
279static inline int
280if_enq_drop(struct ifqueue *ifq, struct mbuf *m)
281{
282        if (IF_QFULL(ifq) &&
283            !if_queue_drop(ifq, m))
284                return 0;
285        IF_ENQUEUE(ifq, m);
286        return 1;
287}
288#else
289
290#ifdef MT_HEADER
291int     if_enq_drop __P((struct ifqueue *, struct mbuf *));
292#endif
293
294#endif
295#endif /* KERNEL */
296
297#define IFQ_MAXLEN      50
298#define IFNET_SLOWHZ    1               /* granularity is 1 second */
299
300/*
301 * The ifaddr structure contains information about one address
302 * of an interface.  They are maintained by the different address families,
303 * are allocated and attached when an address is set, and are linked
304 * together so all addresses for an interface can be located.
305 */
306struct ifaddr {
307        struct  sockaddr *ifa_addr;     /* address of interface */
308        struct  sockaddr *ifa_dstaddr;  /* other end of p-to-p link */
309#define ifa_broadaddr   ifa_dstaddr     /* broadcast address interface */
310        struct  sockaddr *ifa_netmask;  /* used to determine subnet */
311        struct  ifnet *ifa_ifp;         /* back-pointer to interface */
312        struct  ifaddr *ifa_next;       /* next address for interface */
313        void    (*ifa_rtrequest)        /* check or clean routes (+ or -)'d */
314                __P((int, struct rtentry *, struct sockaddr *));
315        u_short ifa_flags;              /* mostly rt_flags for cloning */
316        short   ifa_refcnt;             /* references to this structure */
317        int     ifa_metric;             /* cost of going out this interface */
318#ifdef notdef
319        struct  rtentry *ifa_rt;        /* XXXX for ROUTETOIF ????? */
320#endif
321        int (*ifa_claim_addr)           /* check if an addr goes to this if */
322                __P((struct ifaddr *, struct sockaddr *));
323
324};
325#define IFA_ROUTE       RTF_UP          /* route installed */
326
327/*
328 * Message format for use in obtaining information about interfaces
329 * from getkerninfo and the routing socket
330 */
331struct if_msghdr {
332        u_short ifm_msglen;     /* to skip over non-understood messages */
333        u_char  ifm_version;    /* future binary compatability */
334        u_char  ifm_type;       /* message type */
335        int     ifm_addrs;      /* like rtm_addrs */
336        int     ifm_flags;      /* value of if_flags */
337        u_short ifm_index;      /* index for associated ifp */
338        struct  if_data ifm_data;/* statistics and other data about if */
339};
340
341/*
342 * Message format for use in obtaining information about interface addresses
343 * from getkerninfo and the routing socket
344 */
345struct ifa_msghdr {
346        u_short ifam_msglen;    /* to skip over non-understood messages */
347        u_char  ifam_version;   /* future binary compatability */
348        u_char  ifam_type;      /* message type */
349        int     ifam_addrs;     /* like rtm_addrs */
350        int     ifam_flags;     /* value of ifa_flags */
351        u_short ifam_index;     /* index for associated ifp */
352        int     ifam_metric;    /* value of ifa_metric */
353};
354
355/*
356 * Interface request structure used for socket
357 * ioctl's.  All interface ioctl's must have parameter
358 * definitions which begin with ifr_name.  The
359 * remainder may be interface specific.
360 */
361struct  ifreq {
362#define IFNAMSIZ        16
363        char    ifr_name[IFNAMSIZ];             /* if name, e.g. "en0" */
364        union {
365                struct  sockaddr ifru_addr;
366                struct  sockaddr ifru_dstaddr;
367                struct  sockaddr ifru_broadaddr;
368                short   ifru_flags;
369                int     ifru_metric;
370                int     ifru_mtu;
371                int     ifru_phys;
372                int     ifru_media;
373                caddr_t ifru_data;
374                int     (*ifru_tap)(struct ifnet *, struct ether_header *, struct mbuf *);
375        } ifr_ifru;
376#define ifr_addr        ifr_ifru.ifru_addr      /* address */
377#define ifr_dstaddr     ifr_ifru.ifru_dstaddr   /* other end of p-to-p link */
378#define ifr_broadaddr   ifr_ifru.ifru_broadaddr /* broadcast address */
379#define ifr_flags       ifr_ifru.ifru_flags     /* flags */
380#define ifr_metric      ifr_ifru.ifru_metric    /* metric */
381#define ifr_mtu         ifr_ifru.ifru_mtu       /* mtu */
382#define ifr_phys        ifr_ifru.ifru_phys      /* physical wire */
383#define ifr_media       ifr_ifru.ifru_media     /* physical media */
384#define ifr_data        ifr_ifru.ifru_data      /* for use by interface */
385#define ifr_tap         ifr_ifru.ifru_tap       /* tap function */
386};
387
388struct ifaliasreq {
389        char    ifra_name[IFNAMSIZ];            /* if name, e.g. "en0" */
390        struct  sockaddr ifra_addr;
391        struct  sockaddr ifra_broadaddr;
392        struct  sockaddr ifra_mask;
393};
394
395struct ifmediareq {
396        char    ifm_name[IFNAMSIZ];     /* if name, e.g. "en0" */
397        int     ifm_current;            /* current media options */
398        int     ifm_mask;               /* don't care mask */
399        int     ifm_status;             /* media status */
400        int     ifm_active;             /* active options */
401        int     ifm_count;              /* # entries in ifm_ulist array */
402        int     *ifm_ulist;             /* media words */
403};
404/*
405 * Structure used in SIOCGIFCONF request.
406 * Used to retrieve interface configuration
407 * for machine (useful for programs which
408 * must know all networks accessible).
409 */
410struct  ifconf {
411        int     ifc_len;                /* size of associated buffer */
412        union {
413                caddr_t ifcu_buf;
414                struct  ifreq *ifcu_req;
415        } ifc_ifcu;
416#define ifc_buf ifc_ifcu.ifcu_buf       /* buffer address */
417#define ifc_req ifc_ifcu.ifcu_req       /* array of structures returned */
418};
419
420#include <net/if_arp.h>
421
422#ifdef KERNEL
423#define IFAFREE(ifa) \
424        if ((ifa)->ifa_refcnt <= 0) \
425                ifafree(ifa); \
426        else \
427                (ifa)->ifa_refcnt--;
428
429extern struct   ifnet   *ifnet;
430extern int      ifqmaxlen;
431extern struct   ifnet   loif[];
432extern int      if_index;
433extern struct   ifaddr  **ifnet_addrs;
434
435void    ether_ifattach __P((struct ifnet *));
436void    ether_input __P((struct ifnet *, struct ether_header *, struct mbuf *));
437int     ether_output __P((struct ifnet *,
438           struct mbuf *, struct sockaddr *, struct rtentry *));
439int     ether_ioctl __P((struct ifnet *, int , caddr_t ));
440
441void    if_attach __P((struct ifnet *));
442void    if_down __P((struct ifnet *));
443void    if_up __P((struct ifnet *));
444#ifdef vax
445void    ifubareset __P((int));
446#endif
447/*void  ifinit __P((void));*/ /* declared in systm.h for main() */
448int     ifioctl __P((struct socket *, int, caddr_t, struct proc *));
449int     ifpromisc __P((struct ifnet *, int));
450struct  ifnet *ifunit __P((char *));
451
452int     if_poll_recv_slow __P((struct ifnet *ifp, int *quotap));
453void    if_poll_xmit_slow __P((struct ifnet *ifp, int *quotap));
454void    if_poll_throttle __P((void));
455void    if_poll_unthrottle __P((void *));
456void    if_poll_init __P((void));
457void    if_poll __P((void));
458
459struct  ifaddr *ifa_ifwithaddr __P((struct sockaddr *));
460struct  ifaddr *ifa_ifwithdstaddr __P((struct sockaddr *));
461struct  ifaddr *ifa_ifwithnet __P((struct sockaddr *));
462struct  ifaddr *ifa_ifwithroute __P((int, struct sockaddr *,
463                                        struct sockaddr *));
464struct  ifaddr *ifaof_ifpforaddr __P((struct sockaddr *, struct ifnet *));
465void    ifafree __P((struct ifaddr *));
466
467int     looutput __P((struct ifnet *,
468           struct mbuf *, struct sockaddr *, struct rtentry *));
469#endif /* KERNEL */
470
471#endif /* !_NET_IF_H_ */
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