2 * Copyright (c) 1990, 1991, 1993
3 * The Regents of the University of California. All rights reserved.
5 * This code is derived from the Stanford/CMU enet packet filter,
6 * (net/enet.c) distributed as part of 4.3BSD, and code contributed
7 * to Berkeley by Steven McCanne and Van Jacobson both of Lawrence
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 * 3. All advertising materials mentioning features or use of this software
19 * must display the following acknowledgement:
20 * This product includes software developed by the University of
21 * California, Berkeley and its contributors.
22 * 4. Neither the name of the University nor the names of its contributors
23 * may be used to endorse or promote products derived from this software
24 * without specific prior written permission.
26 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
27 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
28 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
29 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
30 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
31 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
32 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
33 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
34 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
35 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
38 * @(#)bpf.c 8.2 (Berkeley) 3/28/94
40 * $Id: bpf.c,v 1.42 1998/10/04 17:20:22 alex Exp $
50 #define inline __inline
53 #include <sys/param.h>
54 #include <sys/systm.h>
56 #include <sys/malloc.h>
60 #include <sys/signalvar.h>
61 #include <sys/filio.h>
62 #include <sys/sockio.h>
63 #include <sys/ttycom.h>
65 #if defined(sparc) && BSD < 199103
66 #include <sys/stream.h>
70 #include <sys/socket.h>
71 #include <sys/vnode.h>
75 #include <net/bpfdesc.h>
77 #include <netinet/in.h>
78 #include <netinet/if_ether.h>
79 #include <sys/kernel.h>
80 #include <sys/sysctl.h>
82 #include "opt_devfs.h"
85 #include <sys/devfsext.h>
90 * Older BSDs don't have kernel malloc.
94 static caddr_t bpf_alloc();
95 #include <net/bpf_compat.h>
96 #define BPF_BUFSIZE (MCLBYTES-8)
97 #define UIOMOVE(cp, len, code, uio) uiomove(cp, len, code, uio)
99 #define BPF_BUFSIZE 4096
100 #define UIOMOVE(cp, len, code, uio) uiomove(cp, len, uio)
103 #define PRINET 26 /* interruptible */
106 * The default read buffer size is patchable.
108 static int bpf_bufsize = BPF_BUFSIZE;
109 SYSCTL_INT(_debug, OID_AUTO, bpf_bufsize, CTLFLAG_RW,
110 &bpf_bufsize, 0, "");
113 * bpf_iflist is the list of interfaces; each corresponds to an ifnet
114 * bpf_dtab holds the descriptors, indexed by minor device #
116 static struct bpf_if *bpf_iflist;
117 static struct bpf_d bpf_dtab[NBPFILTER];
118 static int bpf_dtab_init;
120 static int bpf_allocbufs __P((struct bpf_d *));
121 static void bpf_attachd __P((struct bpf_d *d, struct bpf_if *bp));
122 static void bpf_detachd __P((struct bpf_d *d));
123 static void bpf_freed __P((struct bpf_d *));
124 static void bpf_ifname __P((struct ifnet *, struct ifreq *));
125 static void bpf_mcopy __P((const void *, void *, size_t));
126 static int bpf_movein __P((struct uio *, int,
127 struct mbuf **, struct sockaddr *, int *));
128 static int bpf_setif __P((struct bpf_d *, struct ifreq *));
130 bpf_wakeup __P((struct bpf_d *));
131 static void catchpacket __P((struct bpf_d *, u_char *, u_int,
132 u_int, void (*)(const void *, void *, size_t)));
133 static void reset_d __P((struct bpf_d *));
134 static int bpf_setf __P((struct bpf_d *, struct bpf_program *));
136 static d_open_t bpfopen;
137 static d_close_t bpfclose;
138 static d_read_t bpfread;
139 static d_write_t bpfwrite;
140 static d_ioctl_t bpfioctl;
141 static d_poll_t bpfpoll;
143 #define CDEV_MAJOR 23
144 static struct cdevsw bpf_cdevsw =
145 { bpfopen, bpfclose, bpfread, bpfwrite, /*23*/
146 bpfioctl, nostop, nullreset, nodevtotty,/* bpf */
147 bpfpoll, nommap, NULL, "bpf", NULL, -1 };
151 bpf_movein(uio, linktype, mp, sockp, datlen)
152 register struct uio *uio;
153 int linktype, *datlen;
154 register struct mbuf **mp;
155 register struct sockaddr *sockp;
163 * Build a sockaddr based on the data link layer type.
164 * We do this at this level because the ethernet header
165 * is copied directly into the data field of the sockaddr.
166 * In the case of SLIP, there is no header and the packet
167 * is forwarded as is.
168 * Also, we are careful to leave room at the front of the mbuf
169 * for the link level header.
174 sockp->sa_family = AF_INET;
179 sockp->sa_family = AF_UNSPEC;
180 /* XXX Would MAXLINKHDR be better? */
181 hlen = sizeof(struct ether_header);
185 #if defined(__FreeBSD__) || defined(__bsdi__)
186 sockp->sa_family = AF_IMPLINK;
189 sockp->sa_family = AF_UNSPEC;
190 /* XXX 4(FORMAC)+6(dst)+6(src)+3(LLC)+5(SNAP) */
197 sockp->sa_family = AF_UNSPEC;
202 case DLT_ATM_RFC1483:
204 * en atm driver requires 4-byte atm pseudo header.
205 * though it isn't standard, vpi:vci needs to be
208 sockp->sa_family = AF_UNSPEC;
209 hlen = 12; /* XXX 4(ATM_PH) + 3(LLC) + 5(SNAP) */
217 len = uio->uio_resid;
218 *datlen = len - hlen;
219 if ((unsigned)len > MCLBYTES)
222 MGETHDR(m, M_WAIT, MT_DATA);
228 if ((m->m_flags & M_EXT) == 0) {
231 if (m->m_len != MCLBYTES) {
237 m->m_pkthdr.len = m->m_len = len;
238 m->m_pkthdr.rcvif = NULL;
241 * Make room for link header.
244 m->m_pkthdr.len -= hlen;
247 m->m_data += hlen; /* XXX */
251 error = UIOMOVE((caddr_t)sockp->sa_data, hlen, UIO_WRITE, uio);
255 error = UIOMOVE(mtod(m, caddr_t), len - hlen, UIO_WRITE, uio);
264 * Attach file to the bpf interface, i.e. make d listen on bp.
265 * Must be called at splimp.
273 * Point d at bp, and add d to the interface's list of listeners.
274 * Finally, point the driver's bpf cookie at the interface so
275 * it will divert packets to bpf.
278 d->bd_next = bp->bif_dlist;
281 bp->bif_ifp->if_bpf = bp;
285 * Detach a file from its interface.
296 * Check if this descriptor had requested promiscuous mode.
297 * If so, turn it off.
301 if (ifpromisc(bp->bif_ifp, 0))
303 * Something is really wrong if we were able to put
304 * the driver into promiscuous mode, but can't
307 panic("bpf: ifpromisc failed");
309 /* Remove d from the interface's descriptor list. */
314 panic("bpf_detachd: descriptor not in list");
317 if (bp->bif_dlist == 0)
319 * Let the driver know that there are no more listeners.
321 d->bd_bif->bif_ifp->if_bpf = 0;
327 * Mark a descriptor free by making it point to itself.
328 * This is probably cheaper than marking with a constant since
329 * the address should be in a register anyway.
331 #define D_ISFREE(d) ((d) == (d)->bd_next)
332 #define D_MARKFREE(d) ((d)->bd_next = (d))
333 #define D_MARKUSED(d) ((d)->bd_next = 0)
336 * Open ethernet device. Returns ENXIO for illegal minor device number,
337 * EBUSY if file is open by another process.
341 bpfopen(dev, flags, fmt, p)
347 register struct bpf_d *d;
349 if (minor(dev) >= NBPFILTER)
352 * Each minor can be opened by only one process. If the requested
353 * minor is in use, return EBUSY.
355 d = &bpf_dtab[minor(dev)];
359 /* Mark "free" and do most initialization. */
360 bzero((char *)d, sizeof(*d));
361 d->bd_bufsize = bpf_bufsize;
368 * Close the descriptor by detaching it from its interface,
369 * deallocating its buffers, and marking it free.
373 bpfclose(dev, flags, fmt, p)
379 register struct bpf_d *d = &bpf_dtab[minor(dev)];
392 * Support for SunOS, which does not have tsleep.
399 struct bpf_d *d = (struct bpf_d *)arg;
404 #define BPF_SLEEP(chan, pri, s, t) bpf_sleep((struct bpf_d *)chan)
408 register struct bpf_d *d;
410 register int rto = d->bd_rtout;
415 timeout(bpf_timeout, (caddr_t)d, rto);
417 st = sleep((caddr_t)d, PRINET|PCATCH);
419 if (d->bd_timedout == 0)
420 untimeout(bpf_timeout, (caddr_t)d);
424 return (st != 0) ? EINTR : 0;
427 #define BPF_SLEEP tsleep
431 * Rotate the packet buffers in descriptor d. Move the store buffer
432 * into the hold slot, and the free buffer into the store slot.
433 * Zero the length of the new store buffer.
435 #define ROTATE_BUFFERS(d) \
436 (d)->bd_hbuf = (d)->bd_sbuf; \
437 (d)->bd_hlen = (d)->bd_slen; \
438 (d)->bd_sbuf = (d)->bd_fbuf; \
442 * bpfread - read next chunk of packets from buffers
445 bpfread(dev, uio, ioflag)
447 register struct uio *uio;
450 register struct bpf_d *d = &bpf_dtab[minor(dev)];
455 * Restrict application to use a buffer the same size as
458 if (uio->uio_resid != d->bd_bufsize)
463 * If the hold buffer is empty, then do a timed sleep, which
464 * ends when the timeout expires or when enough packets
465 * have arrived to fill the store buffer.
467 while (d->bd_hbuf == 0) {
468 if (d->bd_immediate && d->bd_slen != 0) {
470 * A packet(s) either arrived since the previous
471 * read or arrived while we were asleep.
472 * Rotate the buffers and return what's here.
477 if (ioflag & IO_NDELAY)
480 error = BPF_SLEEP((caddr_t)d, PRINET|PCATCH, "bpf",
482 if (error == EINTR || error == ERESTART) {
486 if (error == EWOULDBLOCK) {
488 * On a timeout, return what's in the buffer,
489 * which may be nothing. If there is something
490 * in the store buffer, we can rotate the buffers.
494 * We filled up the buffer in between
495 * getting the timeout and arriving
496 * here, so we don't need to rotate.
500 if (d->bd_slen == 0) {
509 * At this point, we know we have something in the hold slot.
514 * Move data from hold buffer into user space.
515 * We know the entire buffer is transferred since
516 * we checked above that the read buffer is bpf_bufsize bytes.
518 error = UIOMOVE(d->bd_hbuf, d->bd_hlen, UIO_READ, uio);
521 d->bd_fbuf = d->bd_hbuf;
531 * If there are processes sleeping on this descriptor, wake them up.
535 register struct bpf_d *d;
540 if (d->bd_async && d->bd_sig)
542 gsignal (d->bd_pgid, d->bd_sig);
543 else if (p = pfind (-d->bd_pgid))
544 psignal (p, d->bd_sig);
547 selwakeup(&d->bd_sel);
549 d->bd_sel.si_pid = 0;
552 selwakeup(d->bd_selproc, (int)d->bd_selcoll);
560 bpfwrite(dev, uio, ioflag)
565 register struct bpf_d *d = &bpf_dtab[minor(dev)];
569 static struct sockaddr dst;
575 ifp = d->bd_bif->bif_ifp;
577 if (uio->uio_resid == 0)
580 error = bpf_movein(uio, (int)d->bd_bif->bif_dlt, &m, &dst, &datlen);
584 if (datlen > ifp->if_mtu)
589 error = (*ifp->if_output)(ifp, m, &dst, (struct rtentry *)0);
591 error = (*ifp->if_output)(ifp, m, &dst);
595 * The driver frees the mbuf.
601 * Reset a descriptor by flushing its packet buffer and clearing the
602 * receive and drop counts. Should be called at splimp.
609 /* Free the hold buffer. */
610 d->bd_fbuf = d->bd_hbuf;
620 * FIONREAD Check for read packet available.
621 * SIOCGIFADDR Get interface address - convenient hook to driver.
622 * BIOCGBLEN Get buffer len [for read()].
623 * BIOCSETF Set ethernet read filter.
624 * BIOCFLUSH Flush read packet buffer.
625 * BIOCPROMISC Put interface into promiscuous mode.
626 * BIOCGDLT Get link layer type.
627 * BIOCGETIF Get interface name.
628 * BIOCSETIF Set interface.
629 * BIOCSRTIMEOUT Set read timeout.
630 * BIOCGRTIMEOUT Get read timeout.
631 * BIOCGSTATS Get packet stats.
632 * BIOCIMMEDIATE Set immediate mode.
633 * BIOCVERSION Get filter language version.
637 bpfioctl(dev, cmd, addr, flags, p)
644 register struct bpf_d *d = &bpf_dtab[minor(dev)];
654 * Check for read packet available.
677 ifp = d->bd_bif->bif_ifp;
678 error = (*ifp->if_ioctl)(ifp, cmd, addr);
684 * Get buffer len [for read()].
687 *(u_int *)addr = d->bd_bufsize;
700 register u_int size = *(u_int *)addr;
702 if (size > BPF_MAXBUFSIZE)
703 *(u_int *)addr = size = BPF_MAXBUFSIZE;
704 else if (size < BPF_MINBUFSIZE)
705 *(u_int *)addr = size = BPF_MINBUFSIZE;
706 d->bd_bufsize = size;
712 * Set link layer read filter.
715 error = bpf_setf(d, (struct bpf_program *)addr);
719 * Flush read packet buffer.
728 * Put interface into promiscuous mode.
731 if (d->bd_bif == 0) {
733 * No interface attached yet.
739 if (d->bd_promisc == 0) {
740 error = ifpromisc(d->bd_bif->bif_ifp, 1);
748 * Get device parameters.
754 *(u_int *)addr = d->bd_bif->bif_dlt;
758 * Set interface name.
764 bpf_ifname(d->bd_bif->bif_ifp, (struct ifreq *)addr);
771 error = bpf_setif(d, (struct ifreq *)addr);
779 struct timeval *tv = (struct timeval *)addr;
781 d->bd_rtout = tv->tv_sec * hz + tv->tv_usec / tick;
782 if (d->bd_rtout == 0 && tv->tv_usec != 0)
792 struct timeval *tv = (struct timeval *)addr;
793 u_long msec = d->bd_rtout;
796 tv->tv_sec = msec / 1000;
797 tv->tv_usec = msec % 1000;
806 struct bpf_stat *bs = (struct bpf_stat *)addr;
808 bs->bs_recv = d->bd_rcount;
809 bs->bs_drop = d->bd_dcount;
814 * Set immediate mode.
817 d->bd_immediate = *(u_int *)addr;
822 struct bpf_version *bv = (struct bpf_version *)addr;
824 bv->bv_major = BPF_MAJOR_VERSION;
825 bv->bv_minor = BPF_MINOR_VERSION;
829 case FIONBIO: /* Non-blocking I/O */
832 case FIOASYNC: /* Send signal on receive packets */
833 d->bd_async = *(int *)addr;
836 /* N.B. ioctl (FIOSETOWN) and fcntl (F_SETOWN) both end up doing the
837 equivalent of a TIOCSPGRP and hence end up here. *However* TIOCSPGRP's arg
838 is a process group if it's positive and a process id if it's negative. This
839 is exactly the opposite of what the other two functions want! Therefore
840 there is code in ioctl and fcntl to negate the arg before calling here. */
842 case TIOCSPGRP: /* Process or group to send signals to */
843 d->bd_pgid = *(int *)addr;
847 *(int *)addr = d->bd_pgid;
850 case BIOCSRSIG: /* Set receive signal */
854 sig = *(u_int *)addr;
863 *(u_int *)addr = d->bd_sig;
870 * Set d's packet filter program to fp. If this file already has a filter,
871 * free it and replace it. Returns EINVAL for bogus requests.
876 struct bpf_program *fp;
878 struct bpf_insn *fcode, *old;
883 if (fp->bf_insns == 0) {
891 free((caddr_t)old, M_DEVBUF);
895 if (flen > BPF_MAXINSNS)
898 size = flen * sizeof(*fp->bf_insns);
899 fcode = (struct bpf_insn *)malloc(size, M_DEVBUF, M_WAITOK);
900 if (copyin((caddr_t)fp->bf_insns, (caddr_t)fcode, size) == 0 &&
901 bpf_validate(fcode, (int)flen)) {
903 d->bd_filter = fcode;
907 free((caddr_t)old, M_DEVBUF);
911 free((caddr_t)fcode, M_DEVBUF);
916 * Detach a file from its current interface (if attached at all) and attach
917 * to the interface indicated by the name stored in ifr.
918 * Return an errno or 0.
927 struct ifnet *theywant;
929 theywant = ifunit(ifr->ifr_name);
934 * Look through attached interfaces for the named one.
936 for (bp = bpf_iflist; bp != 0; bp = bp->bif_next) {
937 struct ifnet *ifp = bp->bif_ifp;
939 if (ifp == 0 || ifp != theywant)
942 * We found the requested interface.
943 * If it's not up, return an error.
944 * Allocate the packet buffers if we need to.
945 * If we're already attached to requested interface,
946 * just flush the buffer.
948 if ((ifp->if_flags & IFF_UP) == 0)
951 if (d->bd_sbuf == 0) {
952 error = bpf_allocbufs(d);
957 if (bp != d->bd_bif) {
960 * Detach if attached to something else.
975 * Convert an interface name plus unit number of an ifp to a single
976 * name which is returned in the ifr.
983 char *s = ifp->if_name;
984 char *d = ifr->ifr_name;
988 d--; /* back to the null */
989 /* XXX Assume that unit number is less than 10. */
990 *d++ = ifp->if_unit + '0';
995 * Support for select() and poll() system calls
997 * Return true iff the specific operation will not block indefinitely.
998 * Otherwise, return false but make a note that a selwakeup() must be done.
1001 bpfpoll(dev, events, p)
1006 register struct bpf_d *d;
1011 * An imitation of the FIONREAD ioctl code.
1013 d = &bpf_dtab[minor(dev)];
1016 if (events & (POLLIN | POLLRDNORM))
1017 if (d->bd_hlen != 0 || (d->bd_immediate && d->bd_slen != 0))
1018 revents |= events & (POLLIN | POLLRDNORM);
1020 selrecord(p, &d->bd_sel);
1027 * Incoming linkage from device drivers. Process the packet pkt, of length
1028 * pktlen, which is stored in a contiguous buffer. The packet is parsed
1029 * by each process' filter, and if accepted, stashed into the corresponding
1033 bpf_tap(ifp, pkt, pktlen)
1035 register u_char *pkt;
1036 register u_int pktlen;
1039 register struct bpf_d *d;
1040 register u_int slen;
1042 * Note that the ipl does not have to be raised at this point.
1043 * The only problem that could arise here is that if two different
1044 * interfaces shared any data. This is not the case.
1047 for (d = bp->bif_dlist; d != 0; d = d->bd_next) {
1049 slen = bpf_filter(d->bd_filter, pkt, pktlen, pktlen);
1051 catchpacket(d, pkt, pktlen, slen, bcopy);
1056 * Copy data from an mbuf chain into a buffer. This code is derived
1057 * from m_copydata in sys/uipc_mbuf.c.
1060 bpf_mcopy(src_arg, dst_arg, len)
1061 const void *src_arg;
1063 register size_t len;
1065 register const struct mbuf *m;
1066 register u_int count;
1074 count = min(m->m_len, len);
1075 bcopy(mtod(m, void *), dst, count);
1083 * Incoming linkage from device drivers, when packet is in an mbuf chain.
1090 struct bpf_if *bp = ifp->if_bpf;
1096 for (m0 = m; m0 != 0; m0 = m0->m_next)
1097 pktlen += m0->m_len;
1099 for (d = bp->bif_dlist; d != 0; d = d->bd_next) {
1101 slen = bpf_filter(d->bd_filter, (u_char *)m, pktlen, 0);
1103 catchpacket(d, (u_char *)m, pktlen, slen, bpf_mcopy);
1108 * Move the packet data from interface memory (pkt) into the
1109 * store buffer. Return 1 if it's time to wakeup a listener (buffer full),
1110 * otherwise 0. "copy" is the routine called to do the actual data
1111 * transfer. bcopy is passed in to copy contiguous chunks, while
1112 * bpf_mcopy is passed in to copy mbuf chains. In the latter case,
1113 * pkt is really an mbuf.
1116 catchpacket(d, pkt, pktlen, snaplen, cpfn)
1117 register struct bpf_d *d;
1118 register u_char *pkt;
1119 register u_int pktlen, snaplen;
1120 register void (*cpfn) __P((const void *, void *, size_t));
1122 register struct bpf_hdr *hp;
1123 register int totlen, curlen;
1124 register int hdrlen = d->bd_bif->bif_hdrlen;
1126 * Figure out how many bytes to move. If the packet is
1127 * greater or equal to the snapshot length, transfer that
1128 * much. Otherwise, transfer the whole packet (unless
1129 * we hit the buffer size limit).
1131 totlen = hdrlen + min(snaplen, pktlen);
1132 if (totlen > d->bd_bufsize)
1133 totlen = d->bd_bufsize;
1136 * Round up the end of the previous packet to the next longword.
1138 curlen = BPF_WORDALIGN(d->bd_slen);
1139 if (curlen + totlen > d->bd_bufsize) {
1141 * This packet will overflow the storage buffer.
1142 * Rotate the buffers if we can, then wakeup any
1145 if (d->bd_fbuf == 0) {
1147 * We haven't completed the previous read yet,
1148 * so drop the packet.
1157 else if (d->bd_immediate)
1159 * Immediate mode is set. A packet arrived so any
1160 * reads should be woken up.
1165 * Append the bpf header.
1167 hp = (struct bpf_hdr *)(d->bd_sbuf + curlen);
1169 microtime(&hp->bh_tstamp);
1171 uniqtime(&hp->bh_tstamp);
1173 hp->bh_tstamp = time;
1175 hp->bh_datalen = pktlen;
1176 hp->bh_hdrlen = hdrlen;
1178 * Copy the packet data into the store buffer and update its length.
1180 (*cpfn)(pkt, (u_char *)hp + hdrlen, (hp->bh_caplen = totlen - hdrlen));
1181 d->bd_slen = curlen + totlen;
1185 * Initialize all nonzero fields of a descriptor.
1189 register struct bpf_d *d;
1191 d->bd_fbuf = (caddr_t)malloc(d->bd_bufsize, M_DEVBUF, M_WAITOK);
1192 if (d->bd_fbuf == 0)
1195 d->bd_sbuf = (caddr_t)malloc(d->bd_bufsize, M_DEVBUF, M_WAITOK);
1196 if (d->bd_sbuf == 0) {
1197 free(d->bd_fbuf, M_DEVBUF);
1206 * Free buffers currently in use by a descriptor.
1211 register struct bpf_d *d;
1214 * We don't need to lock out interrupts since this descriptor has
1215 * been detached from its interface and it yet hasn't been marked
1218 if (d->bd_sbuf != 0) {
1219 free(d->bd_sbuf, M_DEVBUF);
1220 if (d->bd_hbuf != 0)
1221 free(d->bd_hbuf, M_DEVBUF);
1222 if (d->bd_fbuf != 0)
1223 free(d->bd_fbuf, M_DEVBUF);
1226 free((caddr_t)d->bd_filter, M_DEVBUF);
1232 * Attach an interface to bpf. driverp is a pointer to a (struct bpf_if *)
1233 * in the driver's softc; dlt is the link layer type; hdrlen is the fixed
1234 * size of the link header (variable length headers not yet supported).
1237 bpfattach(ifp, dlt, hdrlen)
1243 bp = (struct bpf_if *)malloc(sizeof(*bp), M_DEVBUF, M_DONTWAIT);
1251 bp->bif_next = bpf_iflist;
1254 bp->bif_ifp->if_bpf = 0;
1257 * Compute the length of the bpf header. This is not necessarily
1258 * equal to SIZEOF_BPF_HDR because we want to insert spacing such
1259 * that the network layer header begins on a longword boundary (for
1260 * performance reasons and to alleviate alignment restrictions).
1262 bp->bif_hdrlen = BPF_WORDALIGN(hdrlen + SIZEOF_BPF_HDR) - hdrlen;
1265 * Mark all the descriptors free if this hasn't been done.
1267 if (!bpf_dtab_init) {
1268 for (i = 0; i < NBPFILTER; ++i)
1269 D_MARKFREE(&bpf_dtab[i]);
1274 printf("bpf: %s%d attached\n", ifp->if_name, ifp->if_unit);
1278 static void *bpf_devfs_token[NBPFILTER];
1281 static int bpf_devsw_installed;
1283 static void bpf_drvinit __P((void *unused));
1293 if( ! bpf_devsw_installed ) {
1294 dev = makedev(CDEV_MAJOR, 0);
1295 cdevsw_add(&dev,&bpf_cdevsw, NULL);
1296 bpf_devsw_installed = 1;
1299 for ( i = 0 ; i < NBPFILTER ; i++ ) {
1300 bpf_devfs_token[i] =
1301 devfs_add_devswf(&bpf_cdevsw, i, DV_CHR, 0, 0,
1308 SYSINIT(bpfdev,SI_SUB_DRIVERS,SI_ORDER_MIDDLE+CDEV_MAJOR,bpf_drvinit,NULL)