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>
44 #include <sys/device.h>
45 #include <sys/malloc.h>
49 #include <sys/signalvar.h>
50 #include <sys/filio.h>
51 #include <sys/sockio.h>
52 #include <sys/ttycom.h>
53 #include <sys/filedesc.h>
55 #include <sys/event.h>
57 #include <sys/socket.h>
58 #include <sys/vnode.h>
60 #include <sys/thread2.h>
64 #include <net/bpfdesc.h>
65 #include <net/netmsg2.h>
66 #include <net/netisr2.h>
68 #include <netinet/in.h>
69 #include <netinet/if_ether.h>
70 #include <sys/kernel.h>
71 #include <sys/sysctl.h>
73 #include <netproto/802_11/ieee80211_dragonfly.h>
75 #include <sys/devfs.h>
77 struct netmsg_bpf_output
{
78 struct netmsg_base base
;
81 struct sockaddr
*nm_dst
;
82 boolean_t nm_feedback
;
85 MALLOC_DEFINE(M_BPF
, "BPF", "BPF data");
86 DEVFS_DEFINE_CLONE_BITMAP(bpf
);
89 #define BPF_PREALLOCATED_UNITS 4
91 #define BPF_PREALLOCATED_UNITS NBPF
97 * The default read buffer size is patchable.
99 static int bpf_bufsize
= BPF_DEFAULTBUFSIZE
;
100 SYSCTL_INT(_debug
, OID_AUTO
, bpf_bufsize
, CTLFLAG_RW
,
101 &bpf_bufsize
, 0, "Current size of bpf buffer");
102 int bpf_maxbufsize
= BPF_MAXBUFSIZE
;
103 SYSCTL_INT(_debug
, OID_AUTO
, bpf_maxbufsize
, CTLFLAG_RW
,
104 &bpf_maxbufsize
, 0, "Maximum size of bpf buffer");
107 * bpf_iflist is the list of interfaces; each corresponds to an ifnet
109 static struct bpf_if
*bpf_iflist
;
111 static struct lwkt_token bpf_token
= LWKT_TOKEN_INITIALIZER(bpf_token
);
113 static int bpf_allocbufs(struct bpf_d
*);
114 static void bpf_attachd(struct bpf_d
*d
, struct bpf_if
*bp
);
115 static void bpf_detachd(struct bpf_d
*d
);
116 static void bpf_resetd(struct bpf_d
*);
117 static void bpf_freed(struct bpf_d
*);
118 static void bpf_mcopy(volatile const void *, volatile void *, size_t);
119 static int bpf_movein(struct uio
*, int, struct mbuf
**,
120 struct sockaddr
*, int *, struct bpf_insn
*);
121 static int bpf_setif(struct bpf_d
*, struct ifreq
*);
122 static void bpf_timed_out(void *);
123 static void bpf_wakeup(struct bpf_d
*);
124 static void catchpacket(struct bpf_d
*, u_char
*, u_int
, u_int
,
125 void (*)(volatile const void *,
126 volatile void *, size_t),
127 const struct timeval
*);
128 static int bpf_setf(struct bpf_d
*, struct bpf_program
*, u_long cmd
);
129 static int bpf_getdltlist(struct bpf_d
*, struct bpf_dltlist
*);
130 static int bpf_setdlt(struct bpf_d
*, u_int
);
131 static void bpf_drvinit(void *unused
);
132 static void bpf_filter_detach(struct knote
*kn
);
133 static int bpf_filter_read(struct knote
*kn
, long hint
);
135 static d_open_t bpfopen
;
136 static d_clone_t bpfclone
;
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_kqfilter_t bpfkqfilter
;
143 #define CDEV_MAJOR 23
144 static struct dev_ops bpf_ops
= {
145 { "bpf", 0, D_MPSAFE
},
151 .d_kqfilter
= bpfkqfilter
156 bpf_movein(struct uio
*uio
, int linktype
, struct mbuf
**mp
,
157 struct sockaddr
*sockp
, int *datlen
, struct bpf_insn
*wfilter
)
159 const struct ieee80211_bpf_params
*p
;
170 * Build a sockaddr based on the data link layer type.
171 * We do this at this level because the ethernet header
172 * is copied directly into the data field of the sockaddr.
173 * In the case of SLIP, there is no header and the packet
174 * is forwarded as is.
175 * Also, we are careful to leave room at the front of the mbuf
176 * for the link level header.
180 sockp
->sa_family
= AF_INET
;
185 sockp
->sa_family
= AF_UNSPEC
;
186 /* XXX Would MAXLINKHDR be better? */
187 hlen
= sizeof(struct ether_header
);
192 sockp
->sa_family
= AF_UNSPEC
;
196 case DLT_ATM_RFC1483
:
198 * en atm driver requires 4-byte atm pseudo header.
199 * though it isn't standard, vpi:vci needs to be
202 sockp
->sa_family
= AF_UNSPEC
;
203 hlen
= 12; /* XXX 4(ATM_PH) + 3(LLC) + 5(SNAP) */
207 sockp
->sa_family
= AF_UNSPEC
;
208 hlen
= 4; /* This should match PPP_HDRLEN */
211 case DLT_IEEE802_11
: /* IEEE 802.11 wireless */
212 sockp
->sa_family
= AF_IEEE80211
;
216 case DLT_IEEE802_11_RADIO
: /* IEEE 802.11 wireless w/ phy params */
217 sockp
->sa_family
= AF_IEEE80211
;
218 sockp
->sa_len
= 12; /* XXX != 0 */
219 hlen
= sizeof(struct ieee80211_bpf_params
);
226 len
= uio
->uio_resid
;
227 *datlen
= len
- hlen
;
228 if ((unsigned)len
> MCLBYTES
)
231 m
= m_getl(len
, M_WAITOK
, MT_DATA
, M_PKTHDR
, NULL
);
234 m
->m_pkthdr
.len
= m
->m_len
= len
;
235 m
->m_pkthdr
.rcvif
= NULL
;
238 if (m
->m_len
< hlen
) {
243 error
= uiomove(mtod(m
, u_char
*), len
, uio
);
247 slen
= bpf_filter(wfilter
, mtod(m
, u_char
*), len
, len
);
254 * Make room for link header, and copy it to sockaddr.
257 if (sockp
->sa_family
== AF_IEEE80211
) {
259 * Collect true length from the parameter header
260 * NB: sockp is known to be zero'd so if we do a
261 * short copy unspecified parameters will be
263 * NB: packet may not be aligned after stripping
267 p
= mtod(m
, const struct ieee80211_bpf_params
*);
269 if (hlen
> sizeof(sockp
->sa_data
)) {
274 bcopy(m
->m_data
, sockp
->sa_data
, hlen
);
275 m
->m_pkthdr
.len
-= hlen
;
277 m
->m_data
+= hlen
; /* XXX */
286 * Attach file to the bpf interface, i.e. make d listen on bp.
287 * Must be called at splimp.
290 bpf_attachd(struct bpf_d
*d
, struct bpf_if
*bp
)
293 * Point d at bp, and add d to the interface's list of listeners.
294 * Finally, point the driver's bpf cookie at the interface so
295 * it will divert packets to bpf.
297 lwkt_gettoken(&bpf_token
);
299 SLIST_INSERT_HEAD(&bp
->bif_dlist
, d
, bd_next
);
300 *bp
->bif_driverp
= bp
;
302 EVENTHANDLER_INVOKE(bpf_track
, bp
->bif_ifp
, bp
->bif_dlt
, 1);
303 lwkt_reltoken(&bpf_token
);
307 * Detach a file from its interface.
310 bpf_detachd(struct bpf_d
*d
)
316 lwkt_gettoken(&bpf_token
);
320 /* Remove d from the interface's descriptor list. */
321 SLIST_REMOVE(&bp
->bif_dlist
, d
, bpf_d
, bd_next
);
323 if (SLIST_EMPTY(&bp
->bif_dlist
)) {
325 * Let the driver know that there are no more listeners.
327 *bp
->bif_driverp
= NULL
;
331 EVENTHANDLER_INVOKE(bpf_track
, ifp
, bp
->bif_dlt
, 0);
334 * Check if this descriptor had requested promiscuous mode.
335 * If so, turn it off.
339 error
= ifpromisc(ifp
, 0);
340 if (error
!= 0 && error
!= ENXIO
) {
342 * ENXIO can happen if a pccard is unplugged,
343 * Something is really wrong if we were able to put
344 * the driver into promiscuous mode, but can't
347 if_printf(ifp
, "bpf_detach: ifpromisc failed(%d)\n",
351 lwkt_reltoken(&bpf_token
);
355 * Open ethernet device. Returns ENXIO for illegal minor device number,
356 * EBUSY if file is open by another process.
360 bpfopen(struct dev_open_args
*ap
)
362 cdev_t dev
= ap
->a_head
.a_dev
;
365 lwkt_gettoken(&bpf_token
);
366 if (ap
->a_cred
->cr_prison
) {
367 lwkt_reltoken(&bpf_token
);
373 * Each minor can be opened by only one process. If the requested
374 * minor is in use, return EBUSY.
377 lwkt_reltoken(&bpf_token
);
381 d
= kmalloc(sizeof *d
, M_BPF
, M_WAITOK
| M_ZERO
);
383 d
->bd_bufsize
= bpf_bufsize
;
387 callout_init(&d
->bd_callout
);
388 lwkt_reltoken(&bpf_token
);
394 bpfclone(struct dev_clone_args
*ap
)
398 unit
= devfs_clone_bitmap_get(&DEVFS_CLONE_BITMAP(bpf
), 0);
399 ap
->a_dev
= make_only_dev(&bpf_ops
, unit
, 0, 0, 0600, "bpf%d", unit
);
405 * Close the descriptor by detaching it from its interface,
406 * deallocating its buffers, and marking it free.
410 bpfclose(struct dev_close_args
*ap
)
412 cdev_t dev
= ap
->a_head
.a_dev
;
413 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
)
424 if (dev
->si_uminor
>= BPF_PREALLOCATED_UNITS
) {
425 devfs_clone_bitmap_put(&DEVFS_CLONE_BITMAP(bpf
), dev
->si_uminor
);
429 lwkt_reltoken(&bpf_token
);
435 * Rotate the packet buffers in descriptor d. Move the store buffer
436 * into the hold slot, and the free buffer into the store slot.
437 * Zero the length of the new store buffer.
439 #define ROTATE_BUFFERS(d) \
440 (d)->bd_hbuf = (d)->bd_sbuf; \
441 (d)->bd_hlen = (d)->bd_slen; \
442 (d)->bd_sbuf = (d)->bd_fbuf; \
446 * bpfread - read next chunk of packets from buffers
449 bpfread(struct dev_read_args
*ap
)
451 cdev_t dev
= ap
->a_head
.a_dev
;
452 struct bpf_d
*d
= dev
->si_drv1
;
456 lwkt_gettoken(&bpf_token
);
458 * Restrict application to use a buffer the same size as
461 if (ap
->a_uio
->uio_resid
!= d
->bd_bufsize
) {
462 lwkt_reltoken(&bpf_token
);
466 if (d
->bd_state
== BPF_WAITING
)
467 callout_stop(&d
->bd_callout
);
468 timed_out
= (d
->bd_state
== BPF_TIMED_OUT
);
469 d
->bd_state
= BPF_IDLE
;
471 * If the hold buffer is empty, then do a timed sleep, which
472 * ends when the timeout expires or when enough packets
473 * have arrived to fill the store buffer.
475 while (d
->bd_hbuf
== NULL
) {
476 if ((d
->bd_immediate
|| (ap
->a_ioflag
& IO_NDELAY
) || timed_out
)
477 && d
->bd_slen
!= 0) {
479 * A packet(s) either arrived since the previous,
480 * We're in immediate mode, or are reading
481 * in non-blocking mode, and a packet(s)
482 * either arrived since the previous
483 * read or arrived while we were asleep.
484 * Rotate the buffers and return what's here.
491 * No data is available, check to see if the bpf device
492 * is still pointed at a real interface. If not, return
493 * ENXIO so that the userland process knows to rebind
494 * it before using it again.
496 if (d
->bd_bif
== NULL
) {
497 lwkt_reltoken(&bpf_token
);
501 if (ap
->a_ioflag
& IO_NDELAY
) {
502 lwkt_reltoken(&bpf_token
);
505 error
= tsleep(d
, PCATCH
, "bpf", d
->bd_rtout
);
506 if (error
== EINTR
|| error
== ERESTART
) {
507 lwkt_reltoken(&bpf_token
);
510 if (error
== EWOULDBLOCK
) {
512 * On a timeout, return what's in the buffer,
513 * which may be nothing. If there is something
514 * in the store buffer, we can rotate the buffers.
518 * We filled up the buffer in between
519 * getting the timeout and arriving
520 * here, so we don't need to rotate.
524 if (d
->bd_slen
== 0) {
525 lwkt_reltoken(&bpf_token
);
533 * At this point, we know we have something in the hold slot.
537 * Move data from hold buffer into user space.
538 * We know the entire buffer is transferred since
539 * we checked above that the read buffer is bpf_bufsize bytes.
541 error
= uiomove(d
->bd_hbuf
, d
->bd_hlen
, ap
->a_uio
);
543 d
->bd_fbuf
= d
->bd_hbuf
;
546 lwkt_reltoken(&bpf_token
);
553 * If there are processes sleeping on this descriptor, wake them up.
556 bpf_wakeup(struct bpf_d
*d
)
558 if (d
->bd_state
== BPF_WAITING
) {
559 callout_stop(&d
->bd_callout
);
560 d
->bd_state
= BPF_IDLE
;
563 if (d
->bd_async
&& d
->bd_sig
&& d
->bd_sigio
)
564 pgsigio(d
->bd_sigio
, d
->bd_sig
, 0);
566 KNOTE(&d
->bd_kq
.ki_note
, 0);
570 bpf_timed_out(void *arg
)
572 struct bpf_d
*d
= (struct bpf_d
*)arg
;
574 if (d
->bd_state
== BPF_WAITING
) {
575 d
->bd_state
= BPF_TIMED_OUT
;
582 bpf_output_dispatch(netmsg_t msg
)
584 struct netmsg_bpf_output
*bmsg
= (struct netmsg_bpf_output
*)msg
;
585 struct ifnet
*ifp
= bmsg
->nm_ifp
;
586 struct mbuf
*mc
= NULL
;
589 if (bmsg
->nm_feedback
) {
590 mc
= m_dup(bmsg
->nm_mbuf
, M_NOWAIT
);
592 mc
->m_pkthdr
.rcvif
= ifp
;
596 * The driver frees the mbuf.
598 error
= ifp
->if_output(ifp
, bmsg
->nm_mbuf
, bmsg
->nm_dst
, NULL
);
599 lwkt_replymsg(&msg
->lmsg
, error
);
603 mc
->m_flags
&= ~M_HASH
;
604 (*ifp
->if_input
)(ifp
, mc
, NULL
, -1);
612 bpfwrite(struct dev_write_args
*ap
)
614 cdev_t dev
= ap
->a_head
.a_dev
;
615 struct bpf_d
*d
= dev
->si_drv1
;
621 struct netmsg_bpf_output bmsg
;
623 lwkt_gettoken(&bpf_token
);
624 if (d
->bd_bif
== NULL
) {
625 lwkt_reltoken(&bpf_token
);
629 ifp
= d
->bd_bif
->bif_ifp
;
631 if (ap
->a_uio
->uio_resid
== 0) {
632 lwkt_reltoken(&bpf_token
);
636 error
= bpf_movein(ap
->a_uio
, (int)d
->bd_bif
->bif_dlt
, &m
,
637 &dst
, &datlen
, d
->bd_wfilter
);
639 lwkt_reltoken(&bpf_token
);
643 if (datlen
> ifp
->if_mtu
) {
645 lwkt_reltoken(&bpf_token
);
650 dst
.sa_family
= pseudo_AF_HDRCMPLT
;
652 netmsg_init(&bmsg
.base
, NULL
, &curthread
->td_msgport
,
653 0, bpf_output_dispatch
);
659 bmsg
.nm_feedback
= TRUE
;
661 bmsg
.nm_feedback
= FALSE
;
663 ret
= lwkt_domsg(netisr_cpuport(0), &bmsg
.base
.lmsg
, 0);
665 lwkt_reltoken(&bpf_token
);
671 * Reset a descriptor by flushing its packet buffer and clearing the
672 * receive and drop counts. Should be called at splimp.
675 bpf_resetd(struct bpf_d
*d
)
678 /* Free the hold buffer. */
679 d
->bd_fbuf
= d
->bd_hbuf
;
689 * FIONREAD Check for read packet available.
690 * SIOCGIFADDR Get interface address - convenient hook to driver.
691 * BIOCGBLEN Get buffer len [for read()].
692 * BIOCSETF Set ethernet read filter.
693 * BIOCSETWF Set ethernet write filter.
694 * BIOCFLUSH Flush read packet buffer.
695 * BIOCPROMISC Put interface into promiscuous mode.
696 * BIOCGDLT Get link layer type.
697 * BIOCGETIF Get interface name.
698 * BIOCSETIF Set interface.
699 * BIOCSRTIMEOUT Set read timeout.
700 * BIOCGRTIMEOUT Get read timeout.
701 * BIOCGSTATS Get packet stats.
702 * BIOCIMMEDIATE Set immediate mode.
703 * BIOCVERSION Get filter language version.
704 * BIOCGHDRCMPLT Get "header already complete" flag
705 * BIOCSHDRCMPLT Set "header already complete" flag
706 * BIOCSFEEDBACK Set packet feedback mode.
707 * BIOCGFEEDBACK Get packet feedback mode.
708 * BIOCGSEESENT Get "see packets sent" flag
709 * BIOCSSEESENT Set "see packets sent" flag
710 * BIOCLOCK Set "locked" flag
714 bpfioctl(struct dev_ioctl_args
*ap
)
716 cdev_t dev
= ap
->a_head
.a_dev
;
717 struct bpf_d
*d
= dev
->si_drv1
;
720 lwkt_gettoken(&bpf_token
);
721 if (d
->bd_state
== BPF_WAITING
)
722 callout_stop(&d
->bd_callout
);
723 d
->bd_state
= BPF_IDLE
;
725 if (d
->bd_locked
== 1) {
744 lwkt_reltoken(&bpf_token
);
754 * Check for read packet available.
764 *(int *)ap
->a_data
= n
;
772 if (d
->bd_bif
== NULL
) {
775 ifp
= d
->bd_bif
->bif_ifp
;
776 ifnet_serialize_all(ifp
);
777 error
= ifp
->if_ioctl(ifp
, ap
->a_cmd
,
778 ap
->a_data
, ap
->a_cred
);
779 ifnet_deserialize_all(ifp
);
785 * Get buffer len [for read()].
788 *(u_int
*)ap
->a_data
= d
->bd_bufsize
;
795 if (d
->bd_bif
!= NULL
) {
798 u_int size
= *(u_int
*)ap
->a_data
;
800 if (size
> bpf_maxbufsize
)
801 *(u_int
*)ap
->a_data
= size
= bpf_maxbufsize
;
802 else if (size
< BPF_MINBUFSIZE
)
803 *(u_int
*)ap
->a_data
= size
= BPF_MINBUFSIZE
;
804 d
->bd_bufsize
= size
;
809 * Set link layer read filter.
813 error
= bpf_setf(d
, (struct bpf_program
*)ap
->a_data
,
818 * Flush read packet buffer.
825 * Put interface into promiscuous mode.
828 if (d
->bd_bif
== NULL
) {
830 * No interface attached yet.
835 if (d
->bd_promisc
== 0) {
836 error
= ifpromisc(d
->bd_bif
->bif_ifp
, 1);
843 * Get device parameters.
846 if (d
->bd_bif
== NULL
)
849 *(u_int
*)ap
->a_data
= d
->bd_bif
->bif_dlt
;
853 * Get a list of supported data link types.
856 if (d
->bd_bif
== NULL
) {
859 error
= bpf_getdltlist(d
,
860 (struct bpf_dltlist
*)ap
->a_data
);
865 * Set data link type.
868 if (d
->bd_bif
== NULL
)
871 error
= bpf_setdlt(d
, *(u_int
*)ap
->a_data
);
875 * Get interface name.
878 if (d
->bd_bif
== NULL
) {
881 struct ifnet
*const ifp
= d
->bd_bif
->bif_ifp
;
882 struct ifreq
*const ifr
= (struct ifreq
*)ap
->a_data
;
884 strlcpy(ifr
->ifr_name
, ifp
->if_xname
,
885 sizeof ifr
->ifr_name
);
893 error
= bpf_setif(d
, (struct ifreq
*)ap
->a_data
);
901 struct timeval
*tv
= (struct timeval
*)ap
->a_data
;
904 * Subtract 1 tick from tvtohz() since this isn't
907 if ((error
= itimerfix(tv
)) == 0)
908 d
->bd_rtout
= tvtohz_low(tv
);
917 struct timeval
*tv
= (struct timeval
*)ap
->a_data
;
919 tv
->tv_sec
= d
->bd_rtout
/ hz
;
920 tv
->tv_usec
= (d
->bd_rtout
% hz
) * ustick
;
929 struct bpf_stat
*bs
= (struct bpf_stat
*)ap
->a_data
;
931 bs
->bs_recv
= d
->bd_rcount
;
932 bs
->bs_drop
= d
->bd_dcount
;
937 * Set immediate mode.
940 d
->bd_immediate
= *(u_int
*)ap
->a_data
;
945 struct bpf_version
*bv
= (struct bpf_version
*)ap
->a_data
;
947 bv
->bv_major
= BPF_MAJOR_VERSION
;
948 bv
->bv_minor
= BPF_MINOR_VERSION
;
953 * Get "header already complete" flag
956 *(u_int
*)ap
->a_data
= d
->bd_hdrcmplt
;
960 * Set "header already complete" flag
963 d
->bd_hdrcmplt
= *(u_int
*)ap
->a_data
? 1 : 0;
967 * Get "see sent packets" flag
970 *(u_int
*)ap
->a_data
= d
->bd_seesent
;
974 * Set "see sent packets" flag
977 d
->bd_seesent
= *(u_int
*)ap
->a_data
;
980 case FIOASYNC
: /* Send signal on receive packets */
981 d
->bd_async
= *(int *)ap
->a_data
;
985 * Set "feed packets from bpf back to input" mode
988 d
->bd_feedback
= *(int *)ap
->a_data
;
992 * Get "feed packets from bpf back to input" mode
995 *(u_int
*)ap
->a_data
= d
->bd_feedback
;
999 error
= fsetown(*(int *)ap
->a_data
, &d
->bd_sigio
);
1003 *(int *)ap
->a_data
= fgetown(&d
->bd_sigio
);
1006 /* This is deprecated, FIOSETOWN should be used instead. */
1008 error
= fsetown(-(*(int *)ap
->a_data
), &d
->bd_sigio
);
1011 /* This is deprecated, FIOGETOWN should be used instead. */
1013 *(int *)ap
->a_data
= -fgetown(&d
->bd_sigio
);
1016 case BIOCSRSIG
: /* Set receive signal */
1020 sig
= *(u_int
*)ap
->a_data
;
1029 *(u_int
*)ap
->a_data
= d
->bd_sig
;
1035 lwkt_reltoken(&bpf_token
);
1041 * Set d's packet filter program to fp. If this file already has a filter,
1042 * free it and replace it. Returns EINVAL for bogus requests.
1045 bpf_setf(struct bpf_d
*d
, struct bpf_program
*fp
, u_long cmd
)
1047 struct bpf_insn
*fcode
, *old
;
1048 u_int wfilter
, flen
, size
;
1050 if (cmd
== BIOCSETWF
) {
1051 old
= d
->bd_wfilter
;
1055 old
= d
->bd_rfilter
;
1057 if (fp
->bf_insns
== NULL
) {
1058 if (fp
->bf_len
!= 0)
1061 d
->bd_wfilter
= NULL
;
1063 d
->bd_rfilter
= NULL
;
1070 if (flen
> BPF_MAXINSNS
)
1073 size
= flen
* sizeof *fp
->bf_insns
;
1074 fcode
= (struct bpf_insn
*)kmalloc(size
, M_BPF
, M_WAITOK
);
1075 if (copyin(fp
->bf_insns
, fcode
, size
) == 0 &&
1076 bpf_validate(fcode
, (int)flen
)) {
1078 d
->bd_wfilter
= fcode
;
1080 d
->bd_rfilter
= fcode
;
1087 kfree(fcode
, M_BPF
);
1092 * Detach a file from its current interface (if attached at all) and attach
1093 * to the interface indicated by the name stored in ifr.
1094 * Return an errno or 0.
1097 bpf_setif(struct bpf_d
*d
, struct ifreq
*ifr
)
1101 struct ifnet
*theywant
;
1105 theywant
= ifunit(ifr
->ifr_name
);
1106 if (theywant
== NULL
) {
1112 * Look through attached interfaces for the named one.
1114 for (bp
= bpf_iflist
; bp
!= NULL
; bp
= bp
->bif_next
) {
1115 struct ifnet
*ifp
= bp
->bif_ifp
;
1117 if (ifp
== NULL
|| ifp
!= theywant
)
1119 /* skip additional entry */
1120 if (bp
->bif_driverp
!= &ifp
->if_bpf
)
1123 * We found the requested interface.
1124 * Allocate the packet buffers if we need to.
1125 * If we're already attached to requested interface,
1126 * just flush the buffer.
1128 if (d
->bd_sbuf
== NULL
) {
1129 error
= bpf_allocbufs(d
);
1135 if (bp
!= d
->bd_bif
) {
1136 if (d
->bd_bif
!= NULL
) {
1138 * Detach if attached to something else.
1157 static struct filterops bpf_read_filtops
=
1158 { FILTEROP_ISFD
, NULL
, bpf_filter_detach
, bpf_filter_read
};
1161 bpfkqfilter(struct dev_kqfilter_args
*ap
)
1163 cdev_t dev
= ap
->a_head
.a_dev
;
1164 struct knote
*kn
= ap
->a_kn
;
1165 struct klist
*klist
;
1168 lwkt_gettoken(&bpf_token
);
1170 if (d
->bd_bif
== NULL
) {
1172 lwkt_reltoken(&bpf_token
);
1177 switch (kn
->kn_filter
) {
1179 kn
->kn_fop
= &bpf_read_filtops
;
1180 kn
->kn_hook
= (caddr_t
)d
;
1183 ap
->a_result
= EOPNOTSUPP
;
1184 lwkt_reltoken(&bpf_token
);
1188 klist
= &d
->bd_kq
.ki_note
;
1189 knote_insert(klist
, kn
);
1190 lwkt_reltoken(&bpf_token
);
1196 bpf_filter_detach(struct knote
*kn
)
1198 struct klist
*klist
;
1201 d
= (struct bpf_d
*)kn
->kn_hook
;
1202 klist
= &d
->bd_kq
.ki_note
;
1203 knote_remove(klist
, kn
);
1207 bpf_filter_read(struct knote
*kn
, long hint
)
1212 d
= (struct bpf_d
*)kn
->kn_hook
;
1213 if (d
->bd_hlen
!= 0 ||
1214 ((d
->bd_immediate
|| d
->bd_state
== BPF_TIMED_OUT
) &&
1218 /* Start the read timeout if necessary. */
1219 if (d
->bd_rtout
> 0 && d
->bd_state
== BPF_IDLE
) {
1220 callout_reset(&d
->bd_callout
, d
->bd_rtout
,
1222 d
->bd_state
= BPF_WAITING
;
1231 * Process the packet pkt of length pktlen. The packet is parsed
1232 * by each listener's filter, and if accepted, stashed into the
1233 * corresponding buffer.
1236 bpf_tap(struct bpf_if
*bp
, u_char
*pkt
, u_int pktlen
)
1243 lwkt_gettoken(&bpf_token
);
1246 lwkt_reltoken(&bpf_token
);
1251 * Note that the ipl does not have to be raised at this point.
1252 * The only problem that could arise here is that if two different
1253 * interfaces shared any data. This is not the case.
1255 SLIST_FOREACH(d
, &bp
->bif_dlist
, bd_next
) {
1257 slen
= bpf_filter(d
->bd_rfilter
, pkt
, pktlen
, pktlen
);
1263 catchpacket(d
, pkt
, pktlen
, slen
, _bcopy
, &tv
);
1266 lwkt_reltoken(&bpf_token
);
1270 * Copy data from an mbuf chain into a buffer. This code is derived
1271 * from m_copydata in sys/uipc_mbuf.c.
1274 bpf_mcopy(volatile const void *src_arg
, volatile void *dst_arg
, size_t len
)
1276 volatile const struct mbuf
*m
;
1278 volatile u_char
*dst
;
1285 count
= min(m
->m_len
, len
);
1286 bcopy(mtod(m
, void *), dst
, count
);
1294 * Process the packet in the mbuf chain m. The packet is parsed by each
1295 * listener's filter, and if accepted, stashed into the corresponding
1299 bpf_mtap(struct bpf_if
*bp
, struct mbuf
*m
)
1306 lwkt_gettoken(&bpf_token
);
1309 lwkt_reltoken(&bpf_token
);
1313 /* Don't compute pktlen, if no descriptor is attached. */
1314 if (SLIST_EMPTY(&bp
->bif_dlist
)) {
1315 lwkt_reltoken(&bpf_token
);
1319 pktlen
= m_lengthm(m
, NULL
);
1321 SLIST_FOREACH(d
, &bp
->bif_dlist
, bd_next
) {
1322 if (!d
->bd_seesent
&& (m
->m_pkthdr
.rcvif
== NULL
))
1325 slen
= bpf_filter(d
->bd_rfilter
, (u_char
*)m
, pktlen
, 0);
1331 catchpacket(d
, (u_char
*)m
, pktlen
, slen
, bpf_mcopy
,
1335 lwkt_reltoken(&bpf_token
);
1339 * Incoming linkage from device drivers, where we have a mbuf chain
1340 * but need to prepend some arbitrary header from a linear buffer.
1342 * Con up a minimal dummy header to pacify bpf. Allocate (only) a
1343 * struct m_hdr on the stack. This is safe as bpf only reads from the
1344 * fields in this header that we initialize, and will not try to free
1345 * it or keep a pointer to it.
1348 bpf_mtap_hdr(struct bpf_if
*arg
, caddr_t data
, u_int dlen
, struct mbuf
*m
,
1358 bpf_mtap(arg
, (struct mbuf
*) &mh
);
1362 bpf_mtap_family(struct bpf_if
*bp
, struct mbuf
*m
, sa_family_t family
)
1366 KKASSERT(family
!= AF_UNSPEC
);
1368 family4
= (u_int
)family
;
1369 bpf_ptap(bp
, m
, &family4
, sizeof(family4
));
1373 * Process the packet in the mbuf chain m with the header in m prepended.
1374 * The packet is parsed by each listener's filter, and if accepted,
1375 * stashed into the corresponding buffer.
1378 bpf_ptap(struct bpf_if
*bp
, struct mbuf
*m
, const void *data
, u_int dlen
)
1383 * Craft on-stack mbuf suitable for passing to bpf_mtap.
1384 * Note that we cut corners here; we only setup what's
1385 * absolutely needed--this mbuf should never go anywhere else.
1388 mb
.m_data
= __DECONST(void *, data
); /* LINTED */
1390 mb
.m_pkthdr
.rcvif
= m
->m_pkthdr
.rcvif
;
1396 * Move the packet data from interface memory (pkt) into the
1397 * store buffer. Return 1 if it's time to wakeup a listener (buffer full),
1398 * otherwise 0. "copy" is the routine called to do the actual data
1399 * transfer. bcopy is passed in to copy contiguous chunks, while
1400 * bpf_mcopy is passed in to copy mbuf chains. In the latter case,
1401 * pkt is really an mbuf.
1404 catchpacket(struct bpf_d
*d
, u_char
*pkt
, u_int pktlen
, u_int snaplen
,
1405 void (*cpfn
)(volatile const void *, volatile void *, size_t),
1406 const struct timeval
*tv
)
1410 int hdrlen
= d
->bd_bif
->bif_hdrlen
;
1413 * Figure out how many bytes to move. If the packet is
1414 * greater or equal to the snapshot length, transfer that
1415 * much. Otherwise, transfer the whole packet (unless
1416 * we hit the buffer size limit).
1418 totlen
= hdrlen
+ min(snaplen
, pktlen
);
1419 if (totlen
> d
->bd_bufsize
)
1420 totlen
= d
->bd_bufsize
;
1423 * Round up the end of the previous packet to the next longword.
1425 curlen
= BPF_WORDALIGN(d
->bd_slen
);
1426 if (curlen
+ totlen
> d
->bd_bufsize
) {
1428 * This packet will overflow the storage buffer.
1429 * Rotate the buffers if we can, then wakeup any
1432 if (d
->bd_fbuf
== NULL
) {
1434 * We haven't completed the previous read yet,
1435 * so drop the packet.
1443 } else if (d
->bd_immediate
|| d
->bd_state
== BPF_TIMED_OUT
) {
1445 * Immediate mode is set, or the read timeout has
1446 * already expired during a select call. A packet
1447 * arrived, so the reader should be woken up.
1453 * Append the bpf header.
1455 hp
= (struct bpf_hdr
*)(d
->bd_sbuf
+ curlen
);
1456 hp
->bh_tstamp
= *tv
;
1457 hp
->bh_datalen
= pktlen
;
1458 hp
->bh_hdrlen
= hdrlen
;
1460 * Copy the packet data into the store buffer and update its length.
1462 (*cpfn
)(pkt
, (u_char
*)hp
+ hdrlen
, (hp
->bh_caplen
= totlen
- hdrlen
));
1463 d
->bd_slen
= curlen
+ totlen
;
1470 * Initialize all nonzero fields of a descriptor.
1473 bpf_allocbufs(struct bpf_d
*d
)
1475 d
->bd_fbuf
= kmalloc(d
->bd_bufsize
, M_BPF
, M_WAITOK
);
1476 d
->bd_sbuf
= kmalloc(d
->bd_bufsize
, M_BPF
, M_WAITOK
);
1483 * Free buffers and packet filter program currently in use by a descriptor.
1487 bpf_freed(struct bpf_d
*d
)
1490 * We don't need to lock out interrupts since this descriptor has
1491 * been detached from its interface and it yet hasn't been marked
1494 if (d
->bd_sbuf
!= NULL
) {
1495 kfree(d
->bd_sbuf
, M_BPF
);
1496 if (d
->bd_hbuf
!= NULL
)
1497 kfree(d
->bd_hbuf
, M_BPF
);
1498 if (d
->bd_fbuf
!= NULL
)
1499 kfree(d
->bd_fbuf
, M_BPF
);
1502 kfree(d
->bd_rfilter
, M_BPF
);
1504 kfree(d
->bd_wfilter
, M_BPF
);
1508 * Attach an interface to bpf. ifp is a pointer to the structure
1509 * defining the interface to be attached, dlt is the link layer type,
1510 * and hdrlen is the fixed size of the link header (variable length
1511 * headers are not yet supported).
1514 bpfattach(struct ifnet
*ifp
, u_int dlt
, u_int hdrlen
)
1516 bpfattach_dlt(ifp
, dlt
, hdrlen
, &ifp
->if_bpf
);
1520 bpfattach_dlt(struct ifnet
*ifp
, u_int dlt
, u_int hdrlen
, struct bpf_if
**driverp
)
1524 bp
= kmalloc(sizeof *bp
, M_BPF
, M_WAITOK
| M_ZERO
);
1526 lwkt_gettoken(&bpf_token
);
1528 SLIST_INIT(&bp
->bif_dlist
);
1531 bp
->bif_driverp
= driverp
;
1532 *bp
->bif_driverp
= NULL
;
1534 bp
->bif_next
= bpf_iflist
;
1538 * Compute the length of the bpf header. This is not necessarily
1539 * equal to SIZEOF_BPF_HDR because we want to insert spacing such
1540 * that the network layer header begins on a longword boundary (for
1541 * performance reasons and to alleviate alignment restrictions).
1543 bp
->bif_hdrlen
= BPF_WORDALIGN(hdrlen
+ SIZEOF_BPF_HDR
) - hdrlen
;
1545 lwkt_reltoken(&bpf_token
);
1548 if_printf(ifp
, "bpf attached\n");
1552 * Detach bpf from an interface. This involves detaching each descriptor
1553 * associated with the interface, and leaving bd_bif NULL. Notify each
1554 * descriptor as it's detached so that any sleepers wake up and get
1558 bpfdetach(struct ifnet
*ifp
)
1560 struct bpf_if
*bp
, *bp_prev
;
1563 lwkt_gettoken(&bpf_token
);
1565 /* Locate BPF interface information */
1567 for (bp
= bpf_iflist
; bp
!= NULL
; bp
= bp
->bif_next
) {
1568 if (ifp
== bp
->bif_ifp
)
1573 /* Interface wasn't attached */
1574 if (bp
->bif_ifp
== NULL
) {
1575 lwkt_reltoken(&bpf_token
);
1576 kprintf("bpfdetach: %s was not attached\n", ifp
->if_xname
);
1580 while ((d
= SLIST_FIRST(&bp
->bif_dlist
)) != NULL
) {
1585 if (bp_prev
!= NULL
)
1586 bp_prev
->bif_next
= bp
->bif_next
;
1588 bpf_iflist
= bp
->bif_next
;
1592 lwkt_reltoken(&bpf_token
);
1596 * Get a list of available data link type of the interface.
1599 bpf_getdltlist(struct bpf_d
*d
, struct bpf_dltlist
*bfl
)
1605 ifp
= d
->bd_bif
->bif_ifp
;
1608 for (bp
= bpf_iflist
; bp
!= NULL
; bp
= bp
->bif_next
) {
1609 if (bp
->bif_ifp
!= ifp
)
1611 if (bfl
->bfl_list
!= NULL
) {
1612 if (n
>= bfl
->bfl_len
) {
1615 error
= copyout(&bp
->bif_dlt
,
1616 bfl
->bfl_list
+ n
, sizeof(u_int
));
1625 * Set the data link type of a BPF instance.
1628 bpf_setdlt(struct bpf_d
*d
, u_int dlt
)
1630 int error
, opromisc
;
1634 if (d
->bd_bif
->bif_dlt
== dlt
)
1636 ifp
= d
->bd_bif
->bif_ifp
;
1637 for (bp
= bpf_iflist
; bp
!= NULL
; bp
= bp
->bif_next
) {
1638 if (bp
->bif_ifp
== ifp
&& bp
->bif_dlt
== dlt
)
1642 opromisc
= d
->bd_promisc
;
1647 error
= ifpromisc(bp
->bif_ifp
, 1);
1649 if_printf(bp
->bif_ifp
,
1650 "bpf_setdlt: ifpromisc failed (%d)\n",
1657 return(bp
== NULL
? EINVAL
: 0);
1663 lwkt_gettoken(&bpf_token
);
1669 lwkt_reltoken(&bpf_token
);
1673 bpf_drvinit(void *unused
)
1677 make_autoclone_dev(&bpf_ops
, &DEVFS_CLONE_BITMAP(bpf
),
1678 bpfclone
, 0, 0, 0600, "bpf");
1679 for (i
= 0; i
< BPF_PREALLOCATED_UNITS
; i
++) {
1680 make_dev(&bpf_ops
, i
, 0, 0, 0600, "bpf%d", i
);
1681 devfs_clone_bitmap_set(&DEVFS_CLONE_BITMAP(bpf
), i
);
1686 bpf_drvuninit(void *unused
)
1688 devfs_clone_handler_del("bpf");
1689 dev_ops_remove_all(&bpf_ops
);
1690 devfs_clone_bitmap_uninit(&DEVFS_CLONE_BITMAP(bpf
));
1693 SYSINIT(bpfdev
, SI_SUB_DRIVERS
, SI_ORDER_MIDDLE
+CDEV_MAJOR
, bpf_drvinit
, NULL
);
1694 SYSUNINIT(bpfdev
, SI_SUB_DRIVERS
,SI_ORDER_MIDDLE
+CDEV_MAJOR
,bpf_drvuninit
, NULL
);
1698 * NOP stubs to allow bpf-using drivers to load and function.
1700 * A 'better' implementation would allow the core bpf functionality
1701 * to be loaded at runtime.
1705 bpf_tap(struct bpf_if
*bp
, u_char
*pkt
, u_int pktlen
)
1710 bpf_mtap(struct bpf_if
*bp
, struct mbuf
*m
)
1715 bpf_ptap(struct bpf_if
*bp
, struct mbuf
*m
, const void *data
, u_int dlen
)
1720 bpfattach(struct ifnet
*ifp
, u_int dlt
, u_int hdrlen
)
1725 bpfattach_dlt(struct ifnet
*ifp
, u_int dlt
, u_int hdrlen
, struct bpf_if
**driverp
)
1730 bpfdetach(struct ifnet
*ifp
)
1735 bpf_filter(const struct bpf_insn
*pc
, u_char
*p
, u_int wirelen
, u_int buflen
)
1737 return -1; /* "no filter" behaviour */