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. Neither the name of the University nor the names of its contributors
19 * may be used to endorse or promote products derived from this software
20 * without specific prior written permission.
22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34 * @(#)bpf.c 8.2 (Berkeley) 3/28/94
36 * $FreeBSD: src/sys/net/bpf.c,v 1.59.2.12 2002/04/14 21:41:48 luigi Exp $
41 #include <sys/param.h>
42 #include <sys/systm.h>
45 #include <sys/device.h>
46 #include <sys/malloc.h>
50 #include <sys/signalvar.h>
51 #include <sys/filio.h>
52 #include <sys/sockio.h>
53 #include <sys/ttycom.h>
54 #include <sys/filedesc.h>
56 #include <sys/event.h>
58 #include <sys/socket.h>
59 #include <sys/vnode.h>
63 #include <net/bpfdesc.h>
64 #include <net/netmsg2.h>
65 #include <net/netisr2.h>
67 #include <netinet/in.h>
68 #include <netinet/if_ether.h>
69 #include <sys/kernel.h>
70 #include <sys/sysctl.h>
72 #include <netproto/802_11/ieee80211_dragonfly.h>
74 #include <sys/devfs.h>
76 MALLOC_DEFINE(M_BPF
, "BPF", "BPF data");
77 DEVFS_DEFINE_CLONE_BITMAP(bpf
);
80 #define BPF_PREALLOCATED_UNITS 4
82 #define BPF_PREALLOCATED_UNITS NBPF
87 struct netmsg_bpf_output
{
88 struct netmsg_base base
;
91 struct sockaddr
*nm_dst
;
92 boolean_t nm_feedback
;
96 * The default read buffer size is patchable.
98 static int bpf_bufsize
= BPF_DEFAULTBUFSIZE
;
99 SYSCTL_INT(_debug
, OID_AUTO
, bpf_bufsize
, CTLFLAG_RW
,
100 &bpf_bufsize
, 0, "Current size of bpf buffer");
101 int bpf_maxbufsize
= BPF_MAXBUFSIZE
;
102 SYSCTL_INT(_debug
, OID_AUTO
, bpf_maxbufsize
, CTLFLAG_RW
,
103 &bpf_maxbufsize
, 0, "Maximum size of bpf buffer");
106 * bpf_iflist is the list of interfaces; each corresponds to an ifnet
108 static struct bpf_if
*bpf_iflist
;
110 static struct lwkt_token bpf_token
= LWKT_TOKEN_INITIALIZER(bpf_token
);
112 static int bpf_allocbufs(struct bpf_d
*);
113 static void bpf_attachd(struct bpf_d
*d
, struct bpf_if
*bp
);
114 static void bpf_detachd(struct bpf_d
*d
);
115 static void bpf_resetd(struct bpf_d
*);
116 static void bpf_freed(struct bpf_d
*);
117 static void bpf_mcopy(volatile const void *, volatile void *, size_t);
118 static int bpf_movein(struct uio
*, int, struct mbuf
**,
119 struct sockaddr
*, int *, struct bpf_insn
*);
120 static int bpf_setif(struct bpf_d
*, struct ifreq
*);
121 static void bpf_timed_out(void *);
122 static void bpf_wakeup(struct bpf_d
*);
123 static void catchpacket(struct bpf_d
*, u_char
*, u_int
, u_int
,
124 void (*)(volatile const void *,
125 volatile void *, size_t),
126 const struct timeval
*);
127 static int bpf_setf(struct bpf_d
*, struct bpf_program
*, u_long cmd
);
128 static int bpf_getdltlist(struct bpf_d
*, struct bpf_dltlist
*);
129 static int bpf_setdlt(struct bpf_d
*, u_int
);
130 static void bpf_drvinit(void *unused
);
131 static void bpf_filter_detach(struct knote
*kn
);
132 static int bpf_filter_read(struct knote
*kn
, long hint
);
134 static d_open_t bpfopen
;
135 static d_clone_t bpfclone
;
136 static d_close_t bpfclose
;
137 static d_read_t bpfread
;
138 static d_write_t bpfwrite
;
139 static d_ioctl_t bpfioctl
;
140 static d_kqfilter_t bpfkqfilter
;
142 #define CDEV_MAJOR 23
143 static struct dev_ops bpf_ops
= {
144 { "bpf", 0, D_MPSAFE
},
150 .d_kqfilter
= bpfkqfilter
155 bpf_movein(struct uio
*uio
, int linktype
, struct mbuf
**mp
,
156 struct sockaddr
*sockp
, int *datlen
, struct bpf_insn
*wfilter
)
158 const struct ieee80211_bpf_params
*p
;
169 * Build a sockaddr based on the data link layer type.
170 * We do this at this level because the ethernet header
171 * is copied directly into the data field of the sockaddr.
172 * In the case of SLIP, there is no header and the packet
173 * is forwarded as is.
174 * Also, we are careful to leave room at the front of the mbuf
175 * for the link level header.
179 sockp
->sa_family
= AF_INET
;
184 sockp
->sa_family
= AF_UNSPEC
;
185 /* XXX Would MAXLINKHDR be better? */
186 hlen
= sizeof(struct ether_header
);
191 sockp
->sa_family
= AF_UNSPEC
;
195 case DLT_ATM_RFC1483
:
197 * en atm driver requires 4-byte atm pseudo header.
198 * though it isn't standard, vpi:vci needs to be
201 sockp
->sa_family
= AF_UNSPEC
;
202 hlen
= 12; /* XXX 4(ATM_PH) + 3(LLC) + 5(SNAP) */
206 sockp
->sa_family
= AF_UNSPEC
;
207 hlen
= 4; /* This should match PPP_HDRLEN */
210 case DLT_IEEE802_11
: /* IEEE 802.11 wireless */
211 sockp
->sa_family
= AF_IEEE80211
;
215 case DLT_IEEE802_11_RADIO
: /* IEEE 802.11 wireless w/ phy params */
216 sockp
->sa_family
= AF_IEEE80211
;
217 sockp
->sa_len
= 12; /* XXX != 0 */
218 hlen
= sizeof(struct ieee80211_bpf_params
);
225 len
= uio
->uio_resid
;
226 *datlen
= len
- hlen
;
227 if ((unsigned)len
> MCLBYTES
)
230 m
= m_getl(len
, M_WAITOK
, MT_DATA
, M_PKTHDR
, NULL
);
233 m
->m_pkthdr
.len
= m
->m_len
= len
;
234 m
->m_pkthdr
.rcvif
= NULL
;
237 if (m
->m_len
< hlen
) {
242 error
= uiomove(mtod(m
, u_char
*), len
, uio
);
246 slen
= bpf_filter(wfilter
, mtod(m
, u_char
*), len
, len
);
253 * Make room for link header, and copy it to sockaddr.
256 if (sockp
->sa_family
== AF_IEEE80211
) {
258 * Collect true length from the parameter header
259 * NB: sockp is known to be zero'd so if we do a
260 * short copy unspecified parameters will be
262 * NB: packet may not be aligned after stripping
266 p
= mtod(m
, const struct ieee80211_bpf_params
*);
268 if (hlen
> sizeof(sockp
->sa_data
)) {
273 bcopy(m
->m_data
, sockp
->sa_data
, hlen
);
274 m
->m_pkthdr
.len
-= hlen
;
276 m
->m_data
+= hlen
; /* XXX */
285 * Attach file to the bpf interface, i.e. make d listen on bp.
286 * Must be called at splimp.
289 bpf_attachd(struct bpf_d
*d
, struct bpf_if
*bp
)
292 * Point d at bp, and add d to the interface's list of listeners.
293 * Finally, point the driver's bpf cookie at the interface so
294 * it will divert packets to bpf.
296 lwkt_gettoken(&bpf_token
);
298 SLIST_INSERT_HEAD(&bp
->bif_dlist
, d
, bd_next
);
299 *bp
->bif_driverp
= bp
;
301 EVENTHANDLER_INVOKE(bpf_track
, bp
->bif_ifp
, bp
->bif_dlt
, 1);
302 lwkt_reltoken(&bpf_token
);
306 * Detach a file from its interface.
309 bpf_detachd(struct bpf_d
*d
)
315 lwkt_gettoken(&bpf_token
);
319 /* Remove d from the interface's descriptor list. */
320 SLIST_REMOVE(&bp
->bif_dlist
, d
, bpf_d
, bd_next
);
322 if (SLIST_EMPTY(&bp
->bif_dlist
)) {
324 * Let the driver know that there are no more listeners.
326 *bp
->bif_driverp
= NULL
;
330 EVENTHANDLER_INVOKE(bpf_track
, ifp
, bp
->bif_dlt
, 0);
333 * Check if this descriptor had requested promiscuous mode.
334 * If so, turn it off.
338 error
= ifpromisc(ifp
, 0);
339 if (error
!= 0 && error
!= ENXIO
) {
341 * ENXIO can happen if a pccard is unplugged,
342 * Something is really wrong if we were able to put
343 * the driver into promiscuous mode, but can't
346 if_printf(ifp
, "bpf_detach: ifpromisc failed(%d)\n",
350 lwkt_reltoken(&bpf_token
);
354 * Open ethernet device. Returns ENXIO for illegal minor device number,
355 * EBUSY if file is open by another process.
359 bpfopen(struct dev_open_args
*ap
)
361 cdev_t dev
= ap
->a_head
.a_dev
;
364 lwkt_gettoken(&bpf_token
);
365 if (ap
->a_cred
->cr_prison
) {
366 lwkt_reltoken(&bpf_token
);
372 * Each minor can be opened by only one process. If the requested
373 * minor is in use, return EBUSY.
376 lwkt_reltoken(&bpf_token
);
380 d
= kmalloc(sizeof *d
, M_BPF
, M_WAITOK
| M_ZERO
);
382 d
->bd_bufsize
= bpf_bufsize
;
386 callout_init(&d
->bd_callout
);
387 lwkt_reltoken(&bpf_token
);
393 bpfclone(struct dev_clone_args
*ap
)
397 unit
= devfs_clone_bitmap_get(&DEVFS_CLONE_BITMAP(bpf
), 0);
398 ap
->a_dev
= make_only_dev(&bpf_ops
, unit
, 0, 0, 0600, "bpf%d", unit
);
404 * Close the descriptor by detaching it from its interface,
405 * deallocating its buffers, and marking it free.
409 bpfclose(struct dev_close_args
*ap
)
411 cdev_t dev
= ap
->a_head
.a_dev
;
412 struct bpf_d
*d
= dev
->si_drv1
;
415 lwkt_gettoken(&bpf_token
);
416 funsetown(&d
->bd_sigio
);
417 if (d
->bd_state
== BPF_WAITING
)
418 callout_stop(&d
->bd_callout
);
419 d
->bd_state
= BPF_IDLE
;
420 if (d
->bd_bif
!= NULL
)
425 unit
= dev
->si_uminor
;
426 if (unit
>= BPF_PREALLOCATED_UNITS
) {
428 devfs_clone_bitmap_put(&DEVFS_CLONE_BITMAP(bpf
), unit
);
431 lwkt_reltoken(&bpf_token
);
437 * Rotate the packet buffers in descriptor d. Move the store buffer
438 * into the hold slot, and the free buffer into the store slot.
439 * Zero the length of the new store buffer.
441 #define ROTATE_BUFFERS(d) \
442 (d)->bd_hbuf = (d)->bd_sbuf; \
443 (d)->bd_hlen = (d)->bd_slen; \
444 (d)->bd_sbuf = (d)->bd_fbuf; \
448 * bpfread - read next chunk of packets from buffers
451 bpfread(struct dev_read_args
*ap
)
453 cdev_t dev
= ap
->a_head
.a_dev
;
454 struct bpf_d
*d
= dev
->si_drv1
;
458 lwkt_gettoken(&bpf_token
);
460 * Restrict application to use a buffer the same size as
463 if (ap
->a_uio
->uio_resid
!= d
->bd_bufsize
) {
464 lwkt_reltoken(&bpf_token
);
468 if (d
->bd_state
== BPF_WAITING
)
469 callout_stop(&d
->bd_callout
);
470 timed_out
= (d
->bd_state
== BPF_TIMED_OUT
);
471 d
->bd_state
= BPF_IDLE
;
473 * If the hold buffer is empty, then do a timed sleep, which
474 * ends when the timeout expires or when enough packets
475 * have arrived to fill the store buffer.
477 while (d
->bd_hbuf
== NULL
) {
478 if ((d
->bd_immediate
|| (ap
->a_ioflag
& IO_NDELAY
) || timed_out
)
479 && d
->bd_slen
!= 0) {
481 * A packet(s) either arrived since the previous,
482 * We're in immediate mode, or are reading
483 * in non-blocking mode, and a packet(s)
484 * either arrived since the previous
485 * read or arrived while we were asleep.
486 * Rotate the buffers and return what's here.
493 * No data is available, check to see if the bpf device
494 * is still pointed at a real interface. If not, return
495 * ENXIO so that the userland process knows to rebind
496 * it before using it again.
498 if (d
->bd_bif
== NULL
) {
499 lwkt_reltoken(&bpf_token
);
503 if (ap
->a_ioflag
& IO_NDELAY
) {
504 lwkt_reltoken(&bpf_token
);
507 error
= tsleep(d
, PCATCH
, "bpf", d
->bd_rtout
);
508 if (error
== EINTR
|| error
== ERESTART
) {
509 lwkt_reltoken(&bpf_token
);
512 if (error
== EWOULDBLOCK
) {
514 * On a timeout, return what's in the buffer,
515 * which may be nothing. If there is something
516 * in the store buffer, we can rotate the buffers.
520 * We filled up the buffer in between
521 * getting the timeout and arriving
522 * here, so we don't need to rotate.
526 if (d
->bd_slen
== 0) {
527 lwkt_reltoken(&bpf_token
);
535 * At this point, we know we have something in the hold slot.
539 * Move data from hold buffer into user space.
540 * We know the entire buffer is transferred since
541 * we checked above that the read buffer is bpf_bufsize bytes.
543 error
= uiomove(d
->bd_hbuf
, d
->bd_hlen
, ap
->a_uio
);
545 d
->bd_fbuf
= d
->bd_hbuf
;
548 lwkt_reltoken(&bpf_token
);
555 * If there are processes sleeping on this descriptor, wake them up.
558 bpf_wakeup(struct bpf_d
*d
)
560 if (d
->bd_state
== BPF_WAITING
) {
561 callout_stop(&d
->bd_callout
);
562 d
->bd_state
= BPF_IDLE
;
565 if (d
->bd_async
&& d
->bd_sig
&& d
->bd_sigio
)
566 pgsigio(d
->bd_sigio
, d
->bd_sig
, 0);
568 KNOTE(&d
->bd_kq
.ki_note
, 0);
572 bpf_timed_out(void *arg
)
574 struct bpf_d
*d
= (struct bpf_d
*)arg
;
576 if (d
->bd_state
== BPF_WAITING
) {
577 d
->bd_state
= BPF_TIMED_OUT
;
584 bpf_output_dispatch(netmsg_t msg
)
586 struct netmsg_bpf_output
*bmsg
= (struct netmsg_bpf_output
*)msg
;
587 struct ifnet
*ifp
= bmsg
->nm_ifp
;
588 struct mbuf
*mc
= NULL
;
591 if (bmsg
->nm_feedback
) {
592 mc
= m_dup(bmsg
->nm_mbuf
, M_NOWAIT
);
594 mc
->m_pkthdr
.rcvif
= ifp
;
598 * The driver frees the mbuf.
600 error
= ifp
->if_output(ifp
, bmsg
->nm_mbuf
, bmsg
->nm_dst
, NULL
);
601 lwkt_replymsg(&msg
->lmsg
, error
);
605 mc
->m_flags
&= ~M_HASH
;
606 (*ifp
->if_input
)(ifp
, mc
, NULL
, -1);
614 bpfwrite(struct dev_write_args
*ap
)
616 cdev_t dev
= ap
->a_head
.a_dev
;
617 struct bpf_d
*d
= dev
->si_drv1
;
623 struct netmsg_bpf_output bmsg
;
625 lwkt_gettoken(&bpf_token
);
626 if (d
->bd_bif
== NULL
) {
627 lwkt_reltoken(&bpf_token
);
631 ifp
= d
->bd_bif
->bif_ifp
;
633 if (ap
->a_uio
->uio_resid
== 0) {
634 lwkt_reltoken(&bpf_token
);
638 error
= bpf_movein(ap
->a_uio
, (int)d
->bd_bif
->bif_dlt
, &m
,
639 &dst
, &datlen
, d
->bd_wfilter
);
641 lwkt_reltoken(&bpf_token
);
645 if (datlen
> ifp
->if_mtu
) {
647 lwkt_reltoken(&bpf_token
);
652 dst
.sa_family
= pseudo_AF_HDRCMPLT
;
654 netmsg_init(&bmsg
.base
, NULL
, &curthread
->td_msgport
,
655 0, bpf_output_dispatch
);
661 bmsg
.nm_feedback
= TRUE
;
663 bmsg
.nm_feedback
= FALSE
;
665 ret
= lwkt_domsg(netisr_cpuport(0), &bmsg
.base
.lmsg
, 0);
667 lwkt_reltoken(&bpf_token
);
673 * Reset a descriptor by flushing its packet buffer and clearing the
674 * receive and drop counts. Should be called at splimp.
677 bpf_resetd(struct bpf_d
*d
)
680 /* Free the hold buffer. */
681 d
->bd_fbuf
= d
->bd_hbuf
;
691 * FIONREAD Check for read packet available.
692 * SIOCGIFADDR Get interface address - convenient hook to driver.
693 * BIOCGBLEN Get buffer len [for read()].
694 * BIOCSETF Set ethernet read filter.
695 * BIOCSETWF Set ethernet write filter.
696 * BIOCFLUSH Flush read packet buffer.
697 * BIOCPROMISC Put interface into promiscuous mode.
698 * BIOCGDLT Get link layer type.
699 * BIOCGETIF Get interface name.
700 * BIOCSETIF Set interface.
701 * BIOCSRTIMEOUT Set read timeout.
702 * BIOCGRTIMEOUT Get read timeout.
703 * BIOCGSTATS Get packet stats.
704 * BIOCIMMEDIATE Set immediate mode.
705 * BIOCVERSION Get filter language version.
706 * BIOCGHDRCMPLT Get "header already complete" flag
707 * BIOCSHDRCMPLT Set "header already complete" flag
708 * BIOCSFEEDBACK Set packet feedback mode.
709 * BIOCGFEEDBACK Get packet feedback mode.
710 * BIOCGSEESENT Get "see packets sent" flag
711 * BIOCSSEESENT Set "see packets sent" flag
712 * BIOCLOCK Set "locked" flag
716 bpfioctl(struct dev_ioctl_args
*ap
)
718 cdev_t dev
= ap
->a_head
.a_dev
;
719 struct bpf_d
*d
= dev
->si_drv1
;
722 lwkt_gettoken(&bpf_token
);
723 if (d
->bd_state
== BPF_WAITING
)
724 callout_stop(&d
->bd_callout
);
725 d
->bd_state
= BPF_IDLE
;
727 if (d
->bd_locked
== 1) {
746 lwkt_reltoken(&bpf_token
);
756 * Check for read packet available.
766 *(int *)ap
->a_data
= n
;
774 if (d
->bd_bif
== NULL
) {
777 ifp
= d
->bd_bif
->bif_ifp
;
778 ifnet_serialize_all(ifp
);
779 error
= ifp
->if_ioctl(ifp
, ap
->a_cmd
,
780 ap
->a_data
, ap
->a_cred
);
781 ifnet_deserialize_all(ifp
);
787 * Get buffer len [for read()].
790 *(u_int
*)ap
->a_data
= d
->bd_bufsize
;
797 if (d
->bd_bif
!= NULL
) {
800 u_int size
= *(u_int
*)ap
->a_data
;
802 if (size
> bpf_maxbufsize
)
803 *(u_int
*)ap
->a_data
= size
= bpf_maxbufsize
;
804 else if (size
< BPF_MINBUFSIZE
)
805 *(u_int
*)ap
->a_data
= size
= BPF_MINBUFSIZE
;
806 d
->bd_bufsize
= size
;
811 * Set link layer read filter.
815 error
= bpf_setf(d
, (struct bpf_program
*)ap
->a_data
,
820 * Flush read packet buffer.
827 * Put interface into promiscuous mode.
830 if (d
->bd_bif
== NULL
) {
832 * No interface attached yet.
837 if (d
->bd_promisc
== 0) {
838 error
= ifpromisc(d
->bd_bif
->bif_ifp
, 1);
845 * Get device parameters.
848 if (d
->bd_bif
== NULL
)
851 *(u_int
*)ap
->a_data
= d
->bd_bif
->bif_dlt
;
855 * Get a list of supported data link types.
858 if (d
->bd_bif
== NULL
) {
861 error
= bpf_getdltlist(d
,
862 (struct bpf_dltlist
*)ap
->a_data
);
867 * Set data link type.
870 if (d
->bd_bif
== NULL
)
873 error
= bpf_setdlt(d
, *(u_int
*)ap
->a_data
);
877 * Get interface name.
880 if (d
->bd_bif
== NULL
) {
883 struct ifnet
*const ifp
= d
->bd_bif
->bif_ifp
;
884 struct ifreq
*const ifr
= (struct ifreq
*)ap
->a_data
;
886 strlcpy(ifr
->ifr_name
, ifp
->if_xname
,
887 sizeof ifr
->ifr_name
);
895 error
= bpf_setif(d
, (struct ifreq
*)ap
->a_data
);
903 struct timeval
*tv
= (struct timeval
*)ap
->a_data
;
906 * Subtract 1 tick from tvtohz() since this isn't
909 if ((error
= itimerfix(tv
)) == 0)
910 d
->bd_rtout
= tvtohz_low(tv
);
919 struct timeval
*tv
= (struct timeval
*)ap
->a_data
;
921 tv
->tv_sec
= d
->bd_rtout
/ hz
;
922 tv
->tv_usec
= (d
->bd_rtout
% hz
) * ustick
;
931 struct bpf_stat
*bs
= (struct bpf_stat
*)ap
->a_data
;
933 bs
->bs_recv
= d
->bd_rcount
;
934 bs
->bs_drop
= d
->bd_dcount
;
939 * Set immediate mode.
942 d
->bd_immediate
= *(u_int
*)ap
->a_data
;
947 struct bpf_version
*bv
= (struct bpf_version
*)ap
->a_data
;
949 bv
->bv_major
= BPF_MAJOR_VERSION
;
950 bv
->bv_minor
= BPF_MINOR_VERSION
;
955 * Get "header already complete" flag
958 *(u_int
*)ap
->a_data
= d
->bd_hdrcmplt
;
962 * Set "header already complete" flag
965 d
->bd_hdrcmplt
= *(u_int
*)ap
->a_data
? 1 : 0;
969 * Get "see sent packets" flag
972 *(u_int
*)ap
->a_data
= d
->bd_seesent
;
976 * Set "see sent packets" flag
979 d
->bd_seesent
= *(u_int
*)ap
->a_data
;
982 case FIOASYNC
: /* Send signal on receive packets */
983 d
->bd_async
= *(int *)ap
->a_data
;
987 * Set "feed packets from bpf back to input" mode
990 d
->bd_feedback
= *(int *)ap
->a_data
;
994 * Get "feed packets from bpf back to input" mode
997 *(u_int
*)ap
->a_data
= d
->bd_feedback
;
1001 error
= fsetown(*(int *)ap
->a_data
, &d
->bd_sigio
);
1005 *(int *)ap
->a_data
= fgetown(&d
->bd_sigio
);
1008 /* This is deprecated, FIOSETOWN should be used instead. */
1010 error
= fsetown(-(*(int *)ap
->a_data
), &d
->bd_sigio
);
1013 /* This is deprecated, FIOGETOWN should be used instead. */
1015 *(int *)ap
->a_data
= -fgetown(&d
->bd_sigio
);
1018 case BIOCSRSIG
: /* Set receive signal */
1022 sig
= *(u_int
*)ap
->a_data
;
1031 *(u_int
*)ap
->a_data
= d
->bd_sig
;
1037 lwkt_reltoken(&bpf_token
);
1043 * Set d's packet filter program to fp. If this file already has a filter,
1044 * free it and replace it. Returns EINVAL for bogus requests.
1047 bpf_setf(struct bpf_d
*d
, struct bpf_program
*fp
, u_long cmd
)
1049 struct bpf_insn
*fcode
, *old
;
1050 u_int wfilter
, flen
, size
;
1052 if (cmd
== BIOCSETWF
) {
1053 old
= d
->bd_wfilter
;
1057 old
= d
->bd_rfilter
;
1059 if (fp
->bf_insns
== NULL
) {
1060 if (fp
->bf_len
!= 0)
1063 d
->bd_wfilter
= NULL
;
1065 d
->bd_rfilter
= NULL
;
1072 if (flen
> BPF_MAXINSNS
)
1075 size
= flen
* sizeof *fp
->bf_insns
;
1076 fcode
= (struct bpf_insn
*)kmalloc(size
, M_BPF
, M_WAITOK
);
1077 if (copyin(fp
->bf_insns
, fcode
, size
) == 0 &&
1078 bpf_validate(fcode
, (int)flen
)) {
1080 d
->bd_wfilter
= fcode
;
1082 d
->bd_rfilter
= fcode
;
1089 kfree(fcode
, M_BPF
);
1094 * Detach a file from its current interface (if attached at all) and attach
1095 * to the interface indicated by the name stored in ifr.
1096 * Return an errno or 0.
1099 bpf_setif(struct bpf_d
*d
, struct ifreq
*ifr
)
1103 struct ifnet
*theywant
;
1107 theywant
= ifunit(ifr
->ifr_name
);
1108 if (theywant
== NULL
) {
1114 * Look through attached interfaces for the named one.
1116 for (bp
= bpf_iflist
; bp
!= NULL
; bp
= bp
->bif_next
) {
1117 struct ifnet
*ifp
= bp
->bif_ifp
;
1119 if (ifp
== NULL
|| ifp
!= theywant
)
1121 /* skip additional entry */
1122 if (bp
->bif_driverp
!= &ifp
->if_bpf
)
1125 * We found the requested interface.
1126 * Allocate the packet buffers if we need to.
1127 * If we're already attached to requested interface,
1128 * just flush the buffer.
1130 if (d
->bd_sbuf
== NULL
) {
1131 error
= bpf_allocbufs(d
);
1137 if (bp
!= d
->bd_bif
) {
1138 if (d
->bd_bif
!= NULL
) {
1140 * Detach if attached to something else.
1159 static struct filterops bpf_read_filtops
=
1160 { FILTEROP_ISFD
, NULL
, bpf_filter_detach
, bpf_filter_read
};
1163 bpfkqfilter(struct dev_kqfilter_args
*ap
)
1165 cdev_t dev
= ap
->a_head
.a_dev
;
1166 struct knote
*kn
= ap
->a_kn
;
1167 struct klist
*klist
;
1170 lwkt_gettoken(&bpf_token
);
1172 if (d
->bd_bif
== NULL
) {
1174 lwkt_reltoken(&bpf_token
);
1179 switch (kn
->kn_filter
) {
1181 kn
->kn_fop
= &bpf_read_filtops
;
1182 kn
->kn_hook
= (caddr_t
)d
;
1185 ap
->a_result
= EOPNOTSUPP
;
1186 lwkt_reltoken(&bpf_token
);
1190 klist
= &d
->bd_kq
.ki_note
;
1191 knote_insert(klist
, kn
);
1192 lwkt_reltoken(&bpf_token
);
1198 bpf_filter_detach(struct knote
*kn
)
1200 struct klist
*klist
;
1203 d
= (struct bpf_d
*)kn
->kn_hook
;
1204 klist
= &d
->bd_kq
.ki_note
;
1205 knote_remove(klist
, kn
);
1209 bpf_filter_read(struct knote
*kn
, long hint
)
1214 d
= (struct bpf_d
*)kn
->kn_hook
;
1215 if (d
->bd_hlen
!= 0 ||
1216 ((d
->bd_immediate
|| d
->bd_state
== BPF_TIMED_OUT
) &&
1220 /* Start the read timeout if necessary. */
1221 if (d
->bd_rtout
> 0 && d
->bd_state
== BPF_IDLE
) {
1222 callout_reset(&d
->bd_callout
, d
->bd_rtout
,
1224 d
->bd_state
= BPF_WAITING
;
1233 * Process the packet pkt of length pktlen. The packet is parsed
1234 * by each listener's filter, and if accepted, stashed into the
1235 * corresponding buffer.
1238 bpf_tap(struct bpf_if
*bp
, u_char
*pkt
, u_int pktlen
)
1245 lwkt_gettoken(&bpf_token
);
1248 lwkt_reltoken(&bpf_token
);
1253 * Note that the ipl does not have to be raised at this point.
1254 * The only problem that could arise here is that if two different
1255 * interfaces shared any data. This is not the case.
1257 SLIST_FOREACH(d
, &bp
->bif_dlist
, bd_next
) {
1259 slen
= bpf_filter(d
->bd_rfilter
, pkt
, pktlen
, pktlen
);
1265 catchpacket(d
, pkt
, pktlen
, slen
, _bcopy
, &tv
);
1268 lwkt_reltoken(&bpf_token
);
1272 * Copy data from an mbuf chain into a buffer. This code is derived
1273 * from m_copydata in sys/uipc_mbuf.c.
1276 bpf_mcopy(volatile const void *src_arg
, volatile void *dst_arg
, size_t len
)
1278 volatile const struct mbuf
*m
;
1280 volatile u_char
*dst
;
1287 count
= min(m
->m_len
, len
);
1288 bcopy(mtod(m
, void *), dst
, count
);
1296 * Process the packet in the mbuf chain m. The packet is parsed by each
1297 * listener's filter, and if accepted, stashed into the corresponding
1301 bpf_mtap(struct bpf_if
*bp
, struct mbuf
*m
)
1308 lwkt_gettoken(&bpf_token
);
1311 lwkt_reltoken(&bpf_token
);
1315 /* Don't compute pktlen, if no descriptor is attached. */
1316 if (SLIST_EMPTY(&bp
->bif_dlist
)) {
1317 lwkt_reltoken(&bpf_token
);
1321 pktlen
= m_lengthm(m
, NULL
);
1323 SLIST_FOREACH(d
, &bp
->bif_dlist
, bd_next
) {
1324 if (!d
->bd_seesent
&& (m
->m_pkthdr
.rcvif
== NULL
))
1327 slen
= bpf_filter(d
->bd_rfilter
, (u_char
*)m
, pktlen
, 0);
1333 catchpacket(d
, (u_char
*)m
, pktlen
, slen
, bpf_mcopy
,
1337 lwkt_reltoken(&bpf_token
);
1341 * Incoming linkage from device drivers, where we have a mbuf chain
1342 * but need to prepend some arbitrary header from a linear buffer.
1344 * Con up a minimal dummy header to pacify bpf. Allocate (only) a
1345 * struct m_hdr on the stack. This is safe as bpf only reads from the
1346 * fields in this header that we initialize, and will not try to free
1347 * it or keep a pointer to it.
1350 bpf_mtap_hdr(struct bpf_if
*arg
, caddr_t data
, u_int dlen
, struct mbuf
*m
,
1360 bpf_mtap(arg
, (struct mbuf
*) &mh
);
1364 bpf_mtap_family(struct bpf_if
*bp
, struct mbuf
*m
, sa_family_t family
)
1368 KKASSERT(family
!= AF_UNSPEC
);
1370 family4
= (u_int
)family
;
1371 bpf_ptap(bp
, m
, &family4
, sizeof(family4
));
1375 * Process the packet in the mbuf chain m with the header in m prepended.
1376 * The packet is parsed by each listener's filter, and if accepted,
1377 * stashed into the corresponding buffer.
1380 bpf_ptap(struct bpf_if
*bp
, struct mbuf
*m
, const void *data
, u_int dlen
)
1385 * Craft on-stack mbuf suitable for passing to bpf_mtap.
1386 * Note that we cut corners here; we only setup what's
1387 * absolutely needed--this mbuf should never go anywhere else.
1390 mb
.m_data
= __DECONST(void *, data
); /* LINTED */
1392 mb
.m_pkthdr
.rcvif
= m
->m_pkthdr
.rcvif
;
1398 * Move the packet data from interface memory (pkt) into the
1399 * store buffer. Return 1 if it's time to wakeup a listener (buffer full),
1400 * otherwise 0. "copy" is the routine called to do the actual data
1401 * transfer. bcopy is passed in to copy contiguous chunks, while
1402 * bpf_mcopy is passed in to copy mbuf chains. In the latter case,
1403 * pkt is really an mbuf.
1406 catchpacket(struct bpf_d
*d
, u_char
*pkt
, u_int pktlen
, u_int snaplen
,
1407 void (*cpfn
)(volatile const void *, volatile void *, size_t),
1408 const struct timeval
*tv
)
1412 int hdrlen
= d
->bd_bif
->bif_hdrlen
;
1415 * Figure out how many bytes to move. If the packet is
1416 * greater or equal to the snapshot length, transfer that
1417 * much. Otherwise, transfer the whole packet (unless
1418 * we hit the buffer size limit).
1420 totlen
= hdrlen
+ min(snaplen
, pktlen
);
1421 if (totlen
> d
->bd_bufsize
)
1422 totlen
= d
->bd_bufsize
;
1425 * Round up the end of the previous packet to the next longword.
1427 curlen
= BPF_WORDALIGN(d
->bd_slen
);
1428 if (curlen
+ totlen
> d
->bd_bufsize
) {
1430 * This packet will overflow the storage buffer.
1431 * Rotate the buffers if we can, then wakeup any
1434 if (d
->bd_fbuf
== NULL
) {
1436 * We haven't completed the previous read yet,
1437 * so drop the packet.
1445 } else if (d
->bd_immediate
|| d
->bd_state
== BPF_TIMED_OUT
) {
1447 * Immediate mode is set, or the read timeout has
1448 * already expired during a select call. A packet
1449 * arrived, so the reader should be woken up.
1455 * Append the bpf header.
1457 hp
= (struct bpf_hdr
*)(d
->bd_sbuf
+ curlen
);
1458 hp
->bh_tstamp
= *tv
;
1459 hp
->bh_datalen
= pktlen
;
1460 hp
->bh_hdrlen
= hdrlen
;
1462 * Copy the packet data into the store buffer and update its length.
1464 (*cpfn
)(pkt
, (u_char
*)hp
+ hdrlen
, (hp
->bh_caplen
= totlen
- hdrlen
));
1465 d
->bd_slen
= curlen
+ totlen
;
1472 * Initialize all nonzero fields of a descriptor.
1475 bpf_allocbufs(struct bpf_d
*d
)
1477 d
->bd_fbuf
= kmalloc(d
->bd_bufsize
, M_BPF
, M_WAITOK
);
1478 d
->bd_sbuf
= kmalloc(d
->bd_bufsize
, M_BPF
, M_WAITOK
);
1485 * Free buffers and packet filter program currently in use by a descriptor.
1489 bpf_freed(struct bpf_d
*d
)
1492 * We don't need to lock out interrupts since this descriptor has
1493 * been detached from its interface and it yet hasn't been marked
1496 if (d
->bd_sbuf
!= NULL
) {
1497 kfree(d
->bd_sbuf
, M_BPF
);
1498 if (d
->bd_hbuf
!= NULL
)
1499 kfree(d
->bd_hbuf
, M_BPF
);
1500 if (d
->bd_fbuf
!= NULL
)
1501 kfree(d
->bd_fbuf
, M_BPF
);
1504 kfree(d
->bd_rfilter
, M_BPF
);
1506 kfree(d
->bd_wfilter
, M_BPF
);
1510 * Attach an interface to bpf. ifp is a pointer to the structure
1511 * defining the interface to be attached, dlt is the link layer type,
1512 * and hdrlen is the fixed size of the link header (variable length
1513 * headers are not yet supported).
1516 bpfattach(struct ifnet
*ifp
, u_int dlt
, u_int hdrlen
)
1518 bpfattach_dlt(ifp
, dlt
, hdrlen
, &ifp
->if_bpf
);
1522 bpfattach_dlt(struct ifnet
*ifp
, u_int dlt
, u_int hdrlen
, struct bpf_if
**driverp
)
1526 bp
= kmalloc(sizeof *bp
, M_BPF
, M_WAITOK
| M_ZERO
);
1528 lwkt_gettoken(&bpf_token
);
1530 SLIST_INIT(&bp
->bif_dlist
);
1533 bp
->bif_driverp
= driverp
;
1534 *bp
->bif_driverp
= NULL
;
1536 bp
->bif_next
= bpf_iflist
;
1540 * Compute the length of the bpf header. This is not necessarily
1541 * equal to SIZEOF_BPF_HDR because we want to insert spacing such
1542 * that the network layer header begins on a longword boundary (for
1543 * performance reasons and to alleviate alignment restrictions).
1545 bp
->bif_hdrlen
= BPF_WORDALIGN(hdrlen
+ SIZEOF_BPF_HDR
) - hdrlen
;
1547 lwkt_reltoken(&bpf_token
);
1550 if_printf(ifp
, "bpf attached\n");
1554 * Detach bpf from an interface. This involves detaching each descriptor
1555 * associated with the interface, and leaving bd_bif NULL. Notify each
1556 * descriptor as it's detached so that any sleepers wake up and get
1560 bpfdetach(struct ifnet
*ifp
)
1562 struct bpf_if
*bp
, *bp_prev
;
1565 lwkt_gettoken(&bpf_token
);
1567 /* Locate BPF interface information */
1569 for (bp
= bpf_iflist
; bp
!= NULL
; bp
= bp
->bif_next
) {
1570 if (ifp
== bp
->bif_ifp
)
1575 /* Interface wasn't attached */
1576 if (bp
->bif_ifp
== NULL
) {
1577 lwkt_reltoken(&bpf_token
);
1578 kprintf("bpfdetach: %s was not attached\n", ifp
->if_xname
);
1582 while ((d
= SLIST_FIRST(&bp
->bif_dlist
)) != NULL
) {
1587 if (bp_prev
!= NULL
)
1588 bp_prev
->bif_next
= bp
->bif_next
;
1590 bpf_iflist
= bp
->bif_next
;
1594 lwkt_reltoken(&bpf_token
);
1598 * Get a list of available data link type of the interface.
1601 bpf_getdltlist(struct bpf_d
*d
, struct bpf_dltlist
*bfl
)
1607 ifp
= d
->bd_bif
->bif_ifp
;
1610 for (bp
= bpf_iflist
; bp
!= NULL
; bp
= bp
->bif_next
) {
1611 if (bp
->bif_ifp
!= ifp
)
1613 if (bfl
->bfl_list
!= NULL
) {
1614 if (n
>= bfl
->bfl_len
) {
1617 error
= copyout(&bp
->bif_dlt
,
1618 bfl
->bfl_list
+ n
, sizeof(u_int
));
1627 * Set the data link type of a BPF instance.
1630 bpf_setdlt(struct bpf_d
*d
, u_int dlt
)
1632 int error
, opromisc
;
1636 if (d
->bd_bif
->bif_dlt
== dlt
)
1638 ifp
= d
->bd_bif
->bif_ifp
;
1639 for (bp
= bpf_iflist
; bp
!= NULL
; bp
= bp
->bif_next
) {
1640 if (bp
->bif_ifp
== ifp
&& bp
->bif_dlt
== dlt
)
1644 opromisc
= d
->bd_promisc
;
1649 error
= ifpromisc(bp
->bif_ifp
, 1);
1651 if_printf(bp
->bif_ifp
,
1652 "bpf_setdlt: ifpromisc failed (%d)\n",
1659 return(bp
== NULL
? EINVAL
: 0);
1665 lwkt_gettoken(&bpf_token
);
1671 lwkt_reltoken(&bpf_token
);
1675 bpf_drvinit(void *unused
)
1679 make_autoclone_dev(&bpf_ops
, &DEVFS_CLONE_BITMAP(bpf
),
1680 bpfclone
, 0, 0, 0600, "bpf");
1681 for (i
= 0; i
< BPF_PREALLOCATED_UNITS
; i
++) {
1682 make_dev(&bpf_ops
, i
, 0, 0, 0600, "bpf%d", i
);
1683 devfs_clone_bitmap_set(&DEVFS_CLONE_BITMAP(bpf
), i
);
1688 bpf_drvuninit(void *unused
)
1690 devfs_clone_handler_del("bpf");
1691 dev_ops_remove_all(&bpf_ops
);
1692 devfs_clone_bitmap_uninit(&DEVFS_CLONE_BITMAP(bpf
));
1695 SYSINIT(bpfdev
, SI_SUB_DRIVERS
, SI_ORDER_MIDDLE
+CDEV_MAJOR
, bpf_drvinit
, NULL
);
1696 SYSUNINIT(bpfdev
, SI_SUB_DRIVERS
,SI_ORDER_MIDDLE
+CDEV_MAJOR
,bpf_drvuninit
, NULL
);
1700 * NOP stubs to allow bpf-using drivers to load and function.
1702 * A 'better' implementation would allow the core bpf functionality
1703 * to be loaded at runtime.
1707 bpf_tap(struct bpf_if
*bp
, u_char
*pkt
, u_int pktlen
)
1712 bpf_mtap(struct bpf_if
*bp
, struct mbuf
*m
)
1717 bpf_ptap(struct bpf_if
*bp
, struct mbuf
*m
, const void *data
, u_int dlen
)
1722 bpfattach(struct ifnet
*ifp
, u_int dlt
, u_int hdrlen
)
1727 bpfattach_dlt(struct ifnet
*ifp
, u_int dlt
, u_int hdrlen
, struct bpf_if
**driverp
)
1732 bpfdetach(struct ifnet
*ifp
)
1737 bpf_filter(const struct bpf_insn
*pc
, u_char
*p
, u_int wirelen
, u_int buflen
)
1739 return -1; /* "no filter" behaviour */