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
;
84 MALLOC_DEFINE(M_BPF
, "BPF", "BPF data");
85 DEVFS_DEFINE_CLONE_BITMAP(bpf
);
88 #define BPF_PREALLOCATED_UNITS 4
90 #define BPF_PREALLOCATED_UNITS NBPF
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(const void *, 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 (*)(const void *, void *, size_t),
125 const struct timeval
*);
126 static int bpf_setf(struct bpf_d
*, struct bpf_program
*, u_long cmd
);
127 static int bpf_getdltlist(struct bpf_d
*, struct bpf_dltlist
*);
128 static int bpf_setdlt(struct bpf_d
*, u_int
);
129 static void bpf_drvinit(void *unused
);
130 static void bpf_filter_detach(struct knote
*kn
);
131 static int bpf_filter_read(struct knote
*kn
, long hint
);
133 static d_open_t bpfopen
;
134 static d_clone_t bpfclone
;
135 static d_close_t bpfclose
;
136 static d_read_t bpfread
;
137 static d_write_t bpfwrite
;
138 static d_ioctl_t bpfioctl
;
139 static d_kqfilter_t bpfkqfilter
;
141 #define CDEV_MAJOR 23
142 static struct dev_ops bpf_ops
= {
143 { "bpf", 0, D_MPSAFE
},
149 .d_kqfilter
= bpfkqfilter
154 bpf_movein(struct uio
*uio
, int linktype
, struct mbuf
**mp
,
155 struct sockaddr
*sockp
, int *datlen
, struct bpf_insn
*wfilter
)
157 const struct ieee80211_bpf_params
*p
;
168 * Build a sockaddr based on the data link layer type.
169 * We do this at this level because the ethernet header
170 * is copied directly into the data field of the sockaddr.
171 * In the case of SLIP, there is no header and the packet
172 * is forwarded as is.
173 * Also, we are careful to leave room at the front of the mbuf
174 * for the link level header.
178 sockp
->sa_family
= AF_INET
;
183 sockp
->sa_family
= AF_UNSPEC
;
184 /* XXX Would MAXLINKHDR be better? */
185 hlen
= sizeof(struct ether_header
);
190 sockp
->sa_family
= AF_UNSPEC
;
194 case DLT_ATM_RFC1483
:
196 * en atm driver requires 4-byte atm pseudo header.
197 * though it isn't standard, vpi:vci needs to be
200 sockp
->sa_family
= AF_UNSPEC
;
201 hlen
= 12; /* XXX 4(ATM_PH) + 3(LLC) + 5(SNAP) */
205 sockp
->sa_family
= AF_UNSPEC
;
206 hlen
= 4; /* This should match PPP_HDRLEN */
209 case DLT_IEEE802_11
: /* IEEE 802.11 wireless */
210 sockp
->sa_family
= AF_IEEE80211
;
214 case DLT_IEEE802_11_RADIO
: /* IEEE 802.11 wireless w/ phy params */
215 sockp
->sa_family
= AF_IEEE80211
;
216 sockp
->sa_len
= 12; /* XXX != 0 */
217 hlen
= sizeof(struct ieee80211_bpf_params
);
224 len
= uio
->uio_resid
;
225 *datlen
= len
- hlen
;
226 if ((unsigned)len
> MCLBYTES
)
229 m
= m_getl(len
, M_WAITOK
, MT_DATA
, M_PKTHDR
, NULL
);
232 m
->m_pkthdr
.len
= m
->m_len
= len
;
233 m
->m_pkthdr
.rcvif
= NULL
;
236 if (m
->m_len
< hlen
) {
241 error
= uiomove(mtod(m
, u_char
*), len
, uio
);
245 slen
= bpf_filter(wfilter
, mtod(m
, u_char
*), len
, len
);
252 * Make room for link header, and copy it to sockaddr.
255 if (sockp
->sa_family
== AF_IEEE80211
) {
257 * Collect true length from the parameter header
258 * NB: sockp is known to be zero'd so if we do a
259 * short copy unspecified parameters will be
261 * NB: packet may not be aligned after stripping
265 p
= mtod(m
, const struct ieee80211_bpf_params
*);
267 if (hlen
> sizeof(sockp
->sa_data
)) {
272 bcopy(m
->m_data
, sockp
->sa_data
, hlen
);
273 m
->m_pkthdr
.len
-= hlen
;
275 m
->m_data
+= hlen
; /* XXX */
284 * Attach file to the bpf interface, i.e. make d listen on bp.
285 * Must be called at splimp.
288 bpf_attachd(struct bpf_d
*d
, struct bpf_if
*bp
)
291 * Point d at bp, and add d to the interface's list of listeners.
292 * Finally, point the driver's bpf cookie at the interface so
293 * it will divert packets to bpf.
295 lwkt_gettoken(&bpf_token
);
297 SLIST_INSERT_HEAD(&bp
->bif_dlist
, d
, bd_next
);
298 *bp
->bif_driverp
= bp
;
300 EVENTHANDLER_INVOKE(bpf_track
, bp
->bif_ifp
, bp
->bif_dlt
, 1);
301 lwkt_reltoken(&bpf_token
);
305 * Detach a file from its interface.
308 bpf_detachd(struct bpf_d
*d
)
314 lwkt_gettoken(&bpf_token
);
318 /* Remove d from the interface's descriptor list. */
319 SLIST_REMOVE(&bp
->bif_dlist
, d
, bpf_d
, bd_next
);
321 if (SLIST_EMPTY(&bp
->bif_dlist
)) {
323 * Let the driver know that there are no more listeners.
325 *bp
->bif_driverp
= NULL
;
329 EVENTHANDLER_INVOKE(bpf_track
, ifp
, bp
->bif_dlt
, 0);
332 * Check if this descriptor had requested promiscuous mode.
333 * If so, turn it off.
337 error
= ifpromisc(ifp
, 0);
338 if (error
!= 0 && error
!= ENXIO
) {
340 * ENXIO can happen if a pccard is unplugged,
341 * Something is really wrong if we were able to put
342 * the driver into promiscuous mode, but can't
345 if_printf(ifp
, "bpf_detach: ifpromisc failed(%d)\n",
349 lwkt_reltoken(&bpf_token
);
353 * Open ethernet device. Returns ENXIO for illegal minor device number,
354 * EBUSY if file is open by another process.
358 bpfopen(struct dev_open_args
*ap
)
360 cdev_t dev
= ap
->a_head
.a_dev
;
363 lwkt_gettoken(&bpf_token
);
364 if (ap
->a_cred
->cr_prison
) {
365 lwkt_reltoken(&bpf_token
);
371 * Each minor can be opened by only one process. If the requested
372 * minor is in use, return EBUSY.
375 lwkt_reltoken(&bpf_token
);
379 d
= kmalloc(sizeof *d
, M_BPF
, M_WAITOK
| M_ZERO
);
381 d
->bd_bufsize
= bpf_bufsize
;
384 callout_init(&d
->bd_callout
);
385 lwkt_reltoken(&bpf_token
);
391 bpfclone(struct dev_clone_args
*ap
)
395 unit
= devfs_clone_bitmap_get(&DEVFS_CLONE_BITMAP(bpf
), 0);
396 ap
->a_dev
= make_only_dev(&bpf_ops
, unit
, 0, 0, 0600, "bpf%d", unit
);
402 * Close the descriptor by detaching it from its interface,
403 * deallocating its buffers, and marking it free.
407 bpfclose(struct dev_close_args
*ap
)
409 cdev_t dev
= ap
->a_head
.a_dev
;
410 struct bpf_d
*d
= dev
->si_drv1
;
412 lwkt_gettoken(&bpf_token
);
413 funsetown(&d
->bd_sigio
);
414 if (d
->bd_state
== BPF_WAITING
)
415 callout_stop(&d
->bd_callout
);
416 d
->bd_state
= BPF_IDLE
;
417 if (d
->bd_bif
!= NULL
)
421 if (dev
->si_uminor
>= BPF_PREALLOCATED_UNITS
) {
422 devfs_clone_bitmap_put(&DEVFS_CLONE_BITMAP(bpf
), dev
->si_uminor
);
426 lwkt_reltoken(&bpf_token
);
432 * Rotate the packet buffers in descriptor d. Move the store buffer
433 * into the hold slot, and the free buffer into the store slot.
434 * Zero the length of the new store buffer.
436 #define ROTATE_BUFFERS(d) \
437 (d)->bd_hbuf = (d)->bd_sbuf; \
438 (d)->bd_hlen = (d)->bd_slen; \
439 (d)->bd_sbuf = (d)->bd_fbuf; \
443 * bpfread - read next chunk of packets from buffers
446 bpfread(struct dev_read_args
*ap
)
448 cdev_t dev
= ap
->a_head
.a_dev
;
449 struct bpf_d
*d
= dev
->si_drv1
;
453 lwkt_gettoken(&bpf_token
);
455 * Restrict application to use a buffer the same size as
458 if (ap
->a_uio
->uio_resid
!= d
->bd_bufsize
) {
459 lwkt_reltoken(&bpf_token
);
463 if (d
->bd_state
== BPF_WAITING
)
464 callout_stop(&d
->bd_callout
);
465 timed_out
= (d
->bd_state
== BPF_TIMED_OUT
);
466 d
->bd_state
= BPF_IDLE
;
468 * If the hold buffer is empty, then do a timed sleep, which
469 * ends when the timeout expires or when enough packets
470 * have arrived to fill the store buffer.
472 while (d
->bd_hbuf
== NULL
) {
473 if ((d
->bd_immediate
|| (ap
->a_ioflag
& IO_NDELAY
) || timed_out
)
474 && d
->bd_slen
!= 0) {
476 * A packet(s) either arrived since the previous,
477 * We're in immediate mode, or are reading
478 * in non-blocking mode, and a packet(s)
479 * either arrived since the previous
480 * read or arrived while we were asleep.
481 * Rotate the buffers and return what's here.
488 * No data is available, check to see if the bpf device
489 * is still pointed at a real interface. If not, return
490 * ENXIO so that the userland process knows to rebind
491 * it before using it again.
493 if (d
->bd_bif
== NULL
) {
494 lwkt_reltoken(&bpf_token
);
498 if (ap
->a_ioflag
& IO_NDELAY
) {
499 lwkt_reltoken(&bpf_token
);
502 error
= tsleep(d
, PCATCH
, "bpf", d
->bd_rtout
);
503 if (error
== EINTR
|| error
== ERESTART
) {
504 lwkt_reltoken(&bpf_token
);
507 if (error
== EWOULDBLOCK
) {
509 * On a timeout, return what's in the buffer,
510 * which may be nothing. If there is something
511 * in the store buffer, we can rotate the buffers.
515 * We filled up the buffer in between
516 * getting the timeout and arriving
517 * here, so we don't need to rotate.
521 if (d
->bd_slen
== 0) {
522 lwkt_reltoken(&bpf_token
);
530 * At this point, we know we have something in the hold slot.
534 * Move data from hold buffer into user space.
535 * We know the entire buffer is transferred since
536 * we checked above that the read buffer is bpf_bufsize bytes.
538 error
= uiomove(d
->bd_hbuf
, d
->bd_hlen
, ap
->a_uio
);
540 d
->bd_fbuf
= d
->bd_hbuf
;
543 lwkt_reltoken(&bpf_token
);
550 * If there are processes sleeping on this descriptor, wake them up.
553 bpf_wakeup(struct bpf_d
*d
)
555 if (d
->bd_state
== BPF_WAITING
) {
556 callout_stop(&d
->bd_callout
);
557 d
->bd_state
= BPF_IDLE
;
560 if (d
->bd_async
&& d
->bd_sig
&& d
->bd_sigio
)
561 pgsigio(d
->bd_sigio
, d
->bd_sig
, 0);
563 KNOTE(&d
->bd_kq
.ki_note
, 0);
567 bpf_timed_out(void *arg
)
569 struct bpf_d
*d
= (struct bpf_d
*)arg
;
571 if (d
->bd_state
== BPF_WAITING
) {
572 d
->bd_state
= BPF_TIMED_OUT
;
579 bpf_output_dispatch(netmsg_t msg
)
581 struct netmsg_bpf_output
*bmsg
= (struct netmsg_bpf_output
*)msg
;
582 struct ifnet
*ifp
= bmsg
->nm_ifp
;
586 * The driver frees the mbuf.
588 error
= ifp
->if_output(ifp
, bmsg
->nm_mbuf
, bmsg
->nm_dst
, NULL
);
589 lwkt_replymsg(&msg
->lmsg
, error
);
593 bpfwrite(struct dev_write_args
*ap
)
595 cdev_t dev
= ap
->a_head
.a_dev
;
596 struct bpf_d
*d
= dev
->si_drv1
;
602 struct netmsg_bpf_output bmsg
;
604 lwkt_gettoken(&bpf_token
);
605 if (d
->bd_bif
== NULL
) {
606 lwkt_reltoken(&bpf_token
);
610 ifp
= d
->bd_bif
->bif_ifp
;
612 if (ap
->a_uio
->uio_resid
== 0) {
613 lwkt_reltoken(&bpf_token
);
617 error
= bpf_movein(ap
->a_uio
, (int)d
->bd_bif
->bif_dlt
, &m
,
618 &dst
, &datlen
, d
->bd_wfilter
);
620 lwkt_reltoken(&bpf_token
);
624 if (datlen
> ifp
->if_mtu
) {
626 lwkt_reltoken(&bpf_token
);
631 dst
.sa_family
= pseudo_AF_HDRCMPLT
;
633 netmsg_init(&bmsg
.base
, NULL
, &curthread
->td_msgport
,
634 0, bpf_output_dispatch
);
639 ret
= lwkt_domsg(netisr_cpuport(0), &bmsg
.base
.lmsg
, 0);
640 lwkt_reltoken(&bpf_token
);
646 * Reset a descriptor by flushing its packet buffer and clearing the
647 * receive and drop counts. Should be called at splimp.
650 bpf_resetd(struct bpf_d
*d
)
653 /* Free the hold buffer. */
654 d
->bd_fbuf
= d
->bd_hbuf
;
664 * FIONREAD Check for read packet available.
665 * SIOCGIFADDR Get interface address - convenient hook to driver.
666 * BIOCGBLEN Get buffer len [for read()].
667 * BIOCSETF Set ethernet read filter.
668 * BIOCSETWF Set ethernet write filter.
669 * BIOCFLUSH Flush read packet buffer.
670 * BIOCPROMISC Put interface into promiscuous mode.
671 * BIOCGDLT Get link layer type.
672 * BIOCGETIF Get interface name.
673 * BIOCSETIF Set interface.
674 * BIOCSRTIMEOUT Set read timeout.
675 * BIOCGRTIMEOUT Get read timeout.
676 * BIOCGSTATS Get packet stats.
677 * BIOCIMMEDIATE Set immediate mode.
678 * BIOCVERSION Get filter language version.
679 * BIOCGHDRCMPLT Get "header already complete" flag
680 * BIOCSHDRCMPLT Set "header already complete" flag
681 * BIOCGSEESENT Get "see packets sent" flag
682 * BIOCSSEESENT Set "see packets sent" flag
683 * BIOCLOCK Set "locked" flag
687 bpfioctl(struct dev_ioctl_args
*ap
)
689 cdev_t dev
= ap
->a_head
.a_dev
;
690 struct bpf_d
*d
= dev
->si_drv1
;
693 lwkt_gettoken(&bpf_token
);
694 if (d
->bd_state
== BPF_WAITING
)
695 callout_stop(&d
->bd_callout
);
696 d
->bd_state
= BPF_IDLE
;
698 if (d
->bd_locked
== 1) {
717 lwkt_reltoken(&bpf_token
);
727 * Check for read packet available.
737 *(int *)ap
->a_data
= n
;
745 if (d
->bd_bif
== NULL
) {
748 ifp
= d
->bd_bif
->bif_ifp
;
749 ifnet_serialize_all(ifp
);
750 error
= ifp
->if_ioctl(ifp
, ap
->a_cmd
,
751 ap
->a_data
, ap
->a_cred
);
752 ifnet_deserialize_all(ifp
);
758 * Get buffer len [for read()].
761 *(u_int
*)ap
->a_data
= d
->bd_bufsize
;
768 if (d
->bd_bif
!= NULL
) {
771 u_int size
= *(u_int
*)ap
->a_data
;
773 if (size
> bpf_maxbufsize
)
774 *(u_int
*)ap
->a_data
= size
= bpf_maxbufsize
;
775 else if (size
< BPF_MINBUFSIZE
)
776 *(u_int
*)ap
->a_data
= size
= BPF_MINBUFSIZE
;
777 d
->bd_bufsize
= size
;
782 * Set link layer read filter.
786 error
= bpf_setf(d
, (struct bpf_program
*)ap
->a_data
,
791 * Flush read packet buffer.
798 * Put interface into promiscuous mode.
801 if (d
->bd_bif
== NULL
) {
803 * No interface attached yet.
808 if (d
->bd_promisc
== 0) {
809 error
= ifpromisc(d
->bd_bif
->bif_ifp
, 1);
816 * Get device parameters.
819 if (d
->bd_bif
== NULL
)
822 *(u_int
*)ap
->a_data
= d
->bd_bif
->bif_dlt
;
826 * Get a list of supported data link types.
829 if (d
->bd_bif
== NULL
) {
832 error
= bpf_getdltlist(d
,
833 (struct bpf_dltlist
*)ap
->a_data
);
838 * Set data link type.
841 if (d
->bd_bif
== NULL
)
844 error
= bpf_setdlt(d
, *(u_int
*)ap
->a_data
);
848 * Get interface name.
851 if (d
->bd_bif
== NULL
) {
854 struct ifnet
*const ifp
= d
->bd_bif
->bif_ifp
;
855 struct ifreq
*const ifr
= (struct ifreq
*)ap
->a_data
;
857 strlcpy(ifr
->ifr_name
, ifp
->if_xname
,
858 sizeof ifr
->ifr_name
);
866 error
= bpf_setif(d
, (struct ifreq
*)ap
->a_data
);
874 struct timeval
*tv
= (struct timeval
*)ap
->a_data
;
877 * Subtract 1 tick from tvtohz() since this isn't
880 if ((error
= itimerfix(tv
)) == 0)
881 d
->bd_rtout
= tvtohz_low(tv
);
890 struct timeval
*tv
= (struct timeval
*)ap
->a_data
;
892 tv
->tv_sec
= d
->bd_rtout
/ hz
;
893 tv
->tv_usec
= (d
->bd_rtout
% hz
) * ustick
;
902 struct bpf_stat
*bs
= (struct bpf_stat
*)ap
->a_data
;
904 bs
->bs_recv
= d
->bd_rcount
;
905 bs
->bs_drop
= d
->bd_dcount
;
910 * Set immediate mode.
913 d
->bd_immediate
= *(u_int
*)ap
->a_data
;
918 struct bpf_version
*bv
= (struct bpf_version
*)ap
->a_data
;
920 bv
->bv_major
= BPF_MAJOR_VERSION
;
921 bv
->bv_minor
= BPF_MINOR_VERSION
;
926 * Get "header already complete" flag
929 *(u_int
*)ap
->a_data
= d
->bd_hdrcmplt
;
933 * Set "header already complete" flag
936 d
->bd_hdrcmplt
= *(u_int
*)ap
->a_data
? 1 : 0;
940 * Get "see sent packets" flag
943 *(u_int
*)ap
->a_data
= d
->bd_seesent
;
947 * Set "see sent packets" flag
950 d
->bd_seesent
= *(u_int
*)ap
->a_data
;
953 case FIOASYNC
: /* Send signal on receive packets */
954 d
->bd_async
= *(int *)ap
->a_data
;
958 error
= fsetown(*(int *)ap
->a_data
, &d
->bd_sigio
);
962 *(int *)ap
->a_data
= fgetown(&d
->bd_sigio
);
965 /* This is deprecated, FIOSETOWN should be used instead. */
967 error
= fsetown(-(*(int *)ap
->a_data
), &d
->bd_sigio
);
970 /* This is deprecated, FIOGETOWN should be used instead. */
972 *(int *)ap
->a_data
= -fgetown(&d
->bd_sigio
);
975 case BIOCSRSIG
: /* Set receive signal */
979 sig
= *(u_int
*)ap
->a_data
;
988 *(u_int
*)ap
->a_data
= d
->bd_sig
;
994 lwkt_reltoken(&bpf_token
);
1000 * Set d's packet filter program to fp. If this file already has a filter,
1001 * free it and replace it. Returns EINVAL for bogus requests.
1004 bpf_setf(struct bpf_d
*d
, struct bpf_program
*fp
, u_long cmd
)
1006 struct bpf_insn
*fcode
, *old
;
1007 u_int wfilter
, flen
, size
;
1009 if (cmd
== BIOCSETWF
) {
1010 old
= d
->bd_wfilter
;
1014 old
= d
->bd_rfilter
;
1016 if (fp
->bf_insns
== NULL
) {
1017 if (fp
->bf_len
!= 0)
1020 d
->bd_wfilter
= NULL
;
1022 d
->bd_rfilter
= NULL
;
1029 if (flen
> BPF_MAXINSNS
)
1032 size
= flen
* sizeof *fp
->bf_insns
;
1033 fcode
= (struct bpf_insn
*)kmalloc(size
, M_BPF
, M_WAITOK
);
1034 if (copyin(fp
->bf_insns
, fcode
, size
) == 0 &&
1035 bpf_validate(fcode
, (int)flen
)) {
1037 d
->bd_wfilter
= fcode
;
1039 d
->bd_rfilter
= fcode
;
1046 kfree(fcode
, M_BPF
);
1051 * Detach a file from its current interface (if attached at all) and attach
1052 * to the interface indicated by the name stored in ifr.
1053 * Return an errno or 0.
1056 bpf_setif(struct bpf_d
*d
, struct ifreq
*ifr
)
1060 struct ifnet
*theywant
;
1064 theywant
= ifunit(ifr
->ifr_name
);
1065 if (theywant
== NULL
) {
1071 * Look through attached interfaces for the named one.
1073 for (bp
= bpf_iflist
; bp
!= NULL
; bp
= bp
->bif_next
) {
1074 struct ifnet
*ifp
= bp
->bif_ifp
;
1076 if (ifp
== NULL
|| ifp
!= theywant
)
1078 /* skip additional entry */
1079 if (bp
->bif_driverp
!= &ifp
->if_bpf
)
1082 * We found the requested interface.
1083 * Allocate the packet buffers if we need to.
1084 * If we're already attached to requested interface,
1085 * just flush the buffer.
1087 if (d
->bd_sbuf
== NULL
) {
1088 error
= bpf_allocbufs(d
);
1094 if (bp
!= d
->bd_bif
) {
1095 if (d
->bd_bif
!= NULL
) {
1097 * Detach if attached to something else.
1116 static struct filterops bpf_read_filtops
=
1117 { FILTEROP_ISFD
, NULL
, bpf_filter_detach
, bpf_filter_read
};
1120 bpfkqfilter(struct dev_kqfilter_args
*ap
)
1122 cdev_t dev
= ap
->a_head
.a_dev
;
1123 struct knote
*kn
= ap
->a_kn
;
1124 struct klist
*klist
;
1127 lwkt_gettoken(&bpf_token
);
1129 if (d
->bd_bif
== NULL
) {
1131 lwkt_reltoken(&bpf_token
);
1136 switch (kn
->kn_filter
) {
1138 kn
->kn_fop
= &bpf_read_filtops
;
1139 kn
->kn_hook
= (caddr_t
)d
;
1142 ap
->a_result
= EOPNOTSUPP
;
1143 lwkt_reltoken(&bpf_token
);
1147 klist
= &d
->bd_kq
.ki_note
;
1148 knote_insert(klist
, kn
);
1149 lwkt_reltoken(&bpf_token
);
1155 bpf_filter_detach(struct knote
*kn
)
1157 struct klist
*klist
;
1160 d
= (struct bpf_d
*)kn
->kn_hook
;
1161 klist
= &d
->bd_kq
.ki_note
;
1162 knote_remove(klist
, kn
);
1166 bpf_filter_read(struct knote
*kn
, long hint
)
1171 d
= (struct bpf_d
*)kn
->kn_hook
;
1172 if (d
->bd_hlen
!= 0 ||
1173 ((d
->bd_immediate
|| d
->bd_state
== BPF_TIMED_OUT
) &&
1177 /* Start the read timeout if necessary. */
1178 if (d
->bd_rtout
> 0 && d
->bd_state
== BPF_IDLE
) {
1179 callout_reset(&d
->bd_callout
, d
->bd_rtout
,
1181 d
->bd_state
= BPF_WAITING
;
1190 * Process the packet pkt of length pktlen. The packet is parsed
1191 * by each listener's filter, and if accepted, stashed into the
1192 * corresponding buffer.
1195 bpf_tap(struct bpf_if
*bp
, u_char
*pkt
, u_int pktlen
)
1202 lwkt_gettoken(&bpf_token
);
1205 lwkt_reltoken(&bpf_token
);
1210 * Note that the ipl does not have to be raised at this point.
1211 * The only problem that could arise here is that if two different
1212 * interfaces shared any data. This is not the case.
1214 SLIST_FOREACH(d
, &bp
->bif_dlist
, bd_next
) {
1216 slen
= bpf_filter(d
->bd_rfilter
, pkt
, pktlen
, pktlen
);
1222 catchpacket(d
, pkt
, pktlen
, slen
, ovbcopy
, &tv
);
1225 lwkt_reltoken(&bpf_token
);
1229 * Copy data from an mbuf chain into a buffer. This code is derived
1230 * from m_copydata in sys/uipc_mbuf.c.
1233 bpf_mcopy(const void *src_arg
, void *dst_arg
, size_t len
)
1235 const struct mbuf
*m
;
1244 count
= min(m
->m_len
, len
);
1245 bcopy(mtod(m
, void *), dst
, count
);
1253 * Process the packet in the mbuf chain m. The packet is parsed by each
1254 * listener's filter, and if accepted, stashed into the corresponding
1258 bpf_mtap(struct bpf_if
*bp
, struct mbuf
*m
)
1265 lwkt_gettoken(&bpf_token
);
1268 lwkt_reltoken(&bpf_token
);
1272 /* Don't compute pktlen, if no descriptor is attached. */
1273 if (SLIST_EMPTY(&bp
->bif_dlist
)) {
1274 lwkt_reltoken(&bpf_token
);
1278 pktlen
= m_lengthm(m
, NULL
);
1280 SLIST_FOREACH(d
, &bp
->bif_dlist
, bd_next
) {
1281 if (!d
->bd_seesent
&& (m
->m_pkthdr
.rcvif
== NULL
))
1284 slen
= bpf_filter(d
->bd_rfilter
, (u_char
*)m
, pktlen
, 0);
1290 catchpacket(d
, (u_char
*)m
, pktlen
, slen
, bpf_mcopy
,
1294 lwkt_reltoken(&bpf_token
);
1298 * Incoming linkage from device drivers, where we have a mbuf chain
1299 * but need to prepend some arbitrary header from a linear buffer.
1301 * Con up a minimal dummy header to pacify bpf. Allocate (only) a
1302 * struct m_hdr on the stack. This is safe as bpf only reads from the
1303 * fields in this header that we initialize, and will not try to free
1304 * it or keep a pointer to it.
1307 bpf_mtap_hdr(struct bpf_if
*arg
, caddr_t data
, u_int dlen
, struct mbuf
*m
,
1317 bpf_mtap(arg
, (struct mbuf
*) &mh
);
1321 bpf_mtap_family(struct bpf_if
*bp
, struct mbuf
*m
, sa_family_t family
)
1325 KKASSERT(family
!= AF_UNSPEC
);
1327 family4
= (u_int
)family
;
1328 bpf_ptap(bp
, m
, &family4
, sizeof(family4
));
1332 * Process the packet in the mbuf chain m with the header in m prepended.
1333 * The packet is parsed by each listener's filter, and if accepted,
1334 * stashed into the corresponding buffer.
1337 bpf_ptap(struct bpf_if
*bp
, struct mbuf
*m
, const void *data
, u_int dlen
)
1342 * Craft on-stack mbuf suitable for passing to bpf_mtap.
1343 * Note that we cut corners here; we only setup what's
1344 * absolutely needed--this mbuf should never go anywhere else.
1347 mb
.m_data
= __DECONST(void *, data
); /* LINTED */
1349 mb
.m_pkthdr
.rcvif
= m
->m_pkthdr
.rcvif
;
1355 * Move the packet data from interface memory (pkt) into the
1356 * store buffer. Return 1 if it's time to wakeup a listener (buffer full),
1357 * otherwise 0. "copy" is the routine called to do the actual data
1358 * transfer. bcopy is passed in to copy contiguous chunks, while
1359 * bpf_mcopy is passed in to copy mbuf chains. In the latter case,
1360 * pkt is really an mbuf.
1363 catchpacket(struct bpf_d
*d
, u_char
*pkt
, u_int pktlen
, u_int snaplen
,
1364 void (*cpfn
)(const void *, void *, size_t),
1365 const struct timeval
*tv
)
1369 int hdrlen
= d
->bd_bif
->bif_hdrlen
;
1372 * Figure out how many bytes to move. If the packet is
1373 * greater or equal to the snapshot length, transfer that
1374 * much. Otherwise, transfer the whole packet (unless
1375 * we hit the buffer size limit).
1377 totlen
= hdrlen
+ min(snaplen
, pktlen
);
1378 if (totlen
> d
->bd_bufsize
)
1379 totlen
= d
->bd_bufsize
;
1382 * Round up the end of the previous packet to the next longword.
1384 curlen
= BPF_WORDALIGN(d
->bd_slen
);
1385 if (curlen
+ totlen
> d
->bd_bufsize
) {
1387 * This packet will overflow the storage buffer.
1388 * Rotate the buffers if we can, then wakeup any
1391 if (d
->bd_fbuf
== NULL
) {
1393 * We haven't completed the previous read yet,
1394 * so drop the packet.
1402 } else if (d
->bd_immediate
|| d
->bd_state
== BPF_TIMED_OUT
) {
1404 * Immediate mode is set, or the read timeout has
1405 * already expired during a select call. A packet
1406 * arrived, so the reader should be woken up.
1412 * Append the bpf header.
1414 hp
= (struct bpf_hdr
*)(d
->bd_sbuf
+ curlen
);
1415 hp
->bh_tstamp
= *tv
;
1416 hp
->bh_datalen
= pktlen
;
1417 hp
->bh_hdrlen
= hdrlen
;
1419 * Copy the packet data into the store buffer and update its length.
1421 (*cpfn
)(pkt
, (u_char
*)hp
+ hdrlen
, (hp
->bh_caplen
= totlen
- hdrlen
));
1422 d
->bd_slen
= curlen
+ totlen
;
1429 * Initialize all nonzero fields of a descriptor.
1432 bpf_allocbufs(struct bpf_d
*d
)
1434 d
->bd_fbuf
= kmalloc(d
->bd_bufsize
, M_BPF
, M_WAITOK
);
1435 d
->bd_sbuf
= kmalloc(d
->bd_bufsize
, M_BPF
, M_WAITOK
);
1442 * Free buffers and packet filter program currently in use by a descriptor.
1446 bpf_freed(struct bpf_d
*d
)
1449 * We don't need to lock out interrupts since this descriptor has
1450 * been detached from its interface and it yet hasn't been marked
1453 if (d
->bd_sbuf
!= NULL
) {
1454 kfree(d
->bd_sbuf
, M_BPF
);
1455 if (d
->bd_hbuf
!= NULL
)
1456 kfree(d
->bd_hbuf
, M_BPF
);
1457 if (d
->bd_fbuf
!= NULL
)
1458 kfree(d
->bd_fbuf
, M_BPF
);
1461 kfree(d
->bd_rfilter
, M_BPF
);
1463 kfree(d
->bd_wfilter
, M_BPF
);
1467 * Attach an interface to bpf. ifp is a pointer to the structure
1468 * defining the interface to be attached, dlt is the link layer type,
1469 * and hdrlen is the fixed size of the link header (variable length
1470 * headers are not yet supported).
1473 bpfattach(struct ifnet
*ifp
, u_int dlt
, u_int hdrlen
)
1475 bpfattach_dlt(ifp
, dlt
, hdrlen
, &ifp
->if_bpf
);
1479 bpfattach_dlt(struct ifnet
*ifp
, u_int dlt
, u_int hdrlen
, struct bpf_if
**driverp
)
1483 bp
= kmalloc(sizeof *bp
, M_BPF
, M_WAITOK
| M_ZERO
);
1485 lwkt_gettoken(&bpf_token
);
1487 SLIST_INIT(&bp
->bif_dlist
);
1490 bp
->bif_driverp
= driverp
;
1491 *bp
->bif_driverp
= NULL
;
1493 bp
->bif_next
= bpf_iflist
;
1497 * Compute the length of the bpf header. This is not necessarily
1498 * equal to SIZEOF_BPF_HDR because we want to insert spacing such
1499 * that the network layer header begins on a longword boundary (for
1500 * performance reasons and to alleviate alignment restrictions).
1502 bp
->bif_hdrlen
= BPF_WORDALIGN(hdrlen
+ SIZEOF_BPF_HDR
) - hdrlen
;
1504 lwkt_reltoken(&bpf_token
);
1507 if_printf(ifp
, "bpf attached\n");
1511 * Detach bpf from an interface. This involves detaching each descriptor
1512 * associated with the interface, and leaving bd_bif NULL. Notify each
1513 * descriptor as it's detached so that any sleepers wake up and get
1517 bpfdetach(struct ifnet
*ifp
)
1519 struct bpf_if
*bp
, *bp_prev
;
1522 lwkt_gettoken(&bpf_token
);
1524 /* Locate BPF interface information */
1526 for (bp
= bpf_iflist
; bp
!= NULL
; bp
= bp
->bif_next
) {
1527 if (ifp
== bp
->bif_ifp
)
1532 /* Interface wasn't attached */
1533 if (bp
->bif_ifp
== NULL
) {
1534 lwkt_reltoken(&bpf_token
);
1535 kprintf("bpfdetach: %s was not attached\n", ifp
->if_xname
);
1539 while ((d
= SLIST_FIRST(&bp
->bif_dlist
)) != NULL
) {
1544 if (bp_prev
!= NULL
)
1545 bp_prev
->bif_next
= bp
->bif_next
;
1547 bpf_iflist
= bp
->bif_next
;
1551 lwkt_reltoken(&bpf_token
);
1555 * Get a list of available data link type of the interface.
1558 bpf_getdltlist(struct bpf_d
*d
, struct bpf_dltlist
*bfl
)
1564 ifp
= d
->bd_bif
->bif_ifp
;
1567 for (bp
= bpf_iflist
; bp
!= NULL
; bp
= bp
->bif_next
) {
1568 if (bp
->bif_ifp
!= ifp
)
1570 if (bfl
->bfl_list
!= NULL
) {
1571 if (n
>= bfl
->bfl_len
) {
1574 error
= copyout(&bp
->bif_dlt
,
1575 bfl
->bfl_list
+ n
, sizeof(u_int
));
1584 * Set the data link type of a BPF instance.
1587 bpf_setdlt(struct bpf_d
*d
, u_int dlt
)
1589 int error
, opromisc
;
1593 if (d
->bd_bif
->bif_dlt
== dlt
)
1595 ifp
= d
->bd_bif
->bif_ifp
;
1596 for (bp
= bpf_iflist
; bp
!= NULL
; bp
= bp
->bif_next
) {
1597 if (bp
->bif_ifp
== ifp
&& bp
->bif_dlt
== dlt
)
1601 opromisc
= d
->bd_promisc
;
1606 error
= ifpromisc(bp
->bif_ifp
, 1);
1608 if_printf(bp
->bif_ifp
,
1609 "bpf_setdlt: ifpromisc failed (%d)\n",
1616 return(bp
== NULL
? EINVAL
: 0);
1622 lwkt_gettoken(&bpf_token
);
1628 lwkt_reltoken(&bpf_token
);
1632 bpf_drvinit(void *unused
)
1636 make_autoclone_dev(&bpf_ops
, &DEVFS_CLONE_BITMAP(bpf
),
1637 bpfclone
, 0, 0, 0600, "bpf");
1638 for (i
= 0; i
< BPF_PREALLOCATED_UNITS
; i
++) {
1639 make_dev(&bpf_ops
, i
, 0, 0, 0600, "bpf%d", i
);
1640 devfs_clone_bitmap_set(&DEVFS_CLONE_BITMAP(bpf
), i
);
1645 bpf_drvuninit(void *unused
)
1647 devfs_clone_handler_del("bpf");
1648 dev_ops_remove_all(&bpf_ops
);
1649 devfs_clone_bitmap_uninit(&DEVFS_CLONE_BITMAP(bpf
));
1652 SYSINIT(bpfdev
, SI_SUB_DRIVERS
, SI_ORDER_MIDDLE
+CDEV_MAJOR
, bpf_drvinit
, NULL
);
1653 SYSUNINIT(bpfdev
, SI_SUB_DRIVERS
,SI_ORDER_MIDDLE
+CDEV_MAJOR
,bpf_drvuninit
, NULL
);
1657 * NOP stubs to allow bpf-using drivers to load and function.
1659 * A 'better' implementation would allow the core bpf functionality
1660 * to be loaded at runtime.
1664 bpf_tap(struct bpf_if
*bp
, u_char
*pkt
, u_int pktlen
)
1669 bpf_mtap(struct bpf_if
*bp
, struct mbuf
*m
)
1674 bpf_ptap(struct bpf_if
*bp
, struct mbuf
*m
, const void *data
, u_int dlen
)
1679 bpfattach(struct ifnet
*ifp
, u_int dlt
, u_int hdrlen
)
1684 bpfattach_dlt(struct ifnet
*ifp
, u_int dlt
, u_int hdrlen
, struct bpf_if
**driverp
)
1689 bpfdetach(struct ifnet
*ifp
)
1694 bpf_filter(const struct bpf_insn
*pc
, u_char
*p
, u_int wirelen
, u_int buflen
)
1696 return -1; /* "no filter" behaviour */