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bpf.c
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bpf.c
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/* $OpenBSD: bpf.c,v 1.203 2021/01/21 12:33:14 dlg Exp $ */
/* $NetBSD: bpf.c,v 1.33 1997/02/21 23:59:35 thorpej Exp $ */
/*
* Copyright (c) 1990, 1991, 1993
* The Regents of the University of California. All rights reserved.
* Copyright (c) 2010, 2014 Henning Brauer <henning@openbsd.org>
*
* This code is derived from the Stanford/CMU enet packet filter,
* (net/enet.c) distributed as part of 4.3BSD, and code contributed
* to Berkeley by Steven McCanne and Van Jacobson both of Lawrence
* Berkeley Laboratory.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* @(#)bpf.c 8.2 (Berkeley) 3/28/94
*/
#include "bpfilter.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/mbuf.h>
#include <sys/proc.h>
#include <sys/signalvar.h>
#include <sys/ioctl.h>
#include <sys/conf.h>
#include <sys/vnode.h>
#include <sys/fcntl.h>
#include <sys/socket.h>
#include <sys/poll.h>
#include <sys/kernel.h>
#include <sys/sysctl.h>
#include <sys/rwlock.h>
#include <sys/atomic.h>
#include <sys/smr.h>
#include <sys/specdev.h>
#include <sys/selinfo.h>
#include <sys/sigio.h>
#include <sys/task.h>
#include <sys/time.h>
#include <net/if.h>
#include <net/bpf.h>
#include <net/bpfdesc.h>
#include <netinet/in.h>
#include <netinet/if_ether.h>
#include "vlan.h"
#if NVLAN > 0
#include <net/if_vlan_var.h>
#endif
#define BPF_BUFSIZE 32768
#define PRINET 26 /* interruptible */
/*
* The default read buffer size is patchable.
*/
int bpf_bufsize = BPF_BUFSIZE;
int bpf_maxbufsize = BPF_MAXBUFSIZE;
/*
* bpf_iflist is the list of interfaces; each corresponds to an ifnet
* bpf_d_list is the list of descriptors
*/
struct bpf_if *bpf_iflist;
LIST_HEAD(, bpf_d) bpf_d_list;
int bpf_allocbufs(struct bpf_d *);
void bpf_ifname(struct bpf_if*, struct ifreq *);
void bpf_mcopy(const void *, void *, size_t);
int bpf_movein(struct uio *, struct bpf_d *, struct mbuf **,
struct sockaddr *);
int bpf_setif(struct bpf_d *, struct ifreq *);
int bpfpoll(dev_t, int, struct proc *);
int bpfkqfilter(dev_t, struct knote *);
void bpf_wakeup(struct bpf_d *);
void bpf_wakeup_cb(void *);
int _bpf_mtap(caddr_t, const struct mbuf *, const struct mbuf *, u_int);
void bpf_catchpacket(struct bpf_d *, u_char *, size_t, size_t,
const struct bpf_hdr *);
int bpf_getdltlist(struct bpf_d *, struct bpf_dltlist *);
int bpf_setdlt(struct bpf_d *, u_int);
void filt_bpfrdetach(struct knote *);
int filt_bpfread(struct knote *, long);
int bpf_sysctl_locked(int *, u_int, void *, size_t *, void *, size_t);
struct bpf_d *bpfilter_lookup(int);
/*
* Called holding ``bd_mtx''.
*/
void bpf_attachd(struct bpf_d *, struct bpf_if *);
void bpf_detachd(struct bpf_d *);
void bpf_resetd(struct bpf_d *);
void bpf_prog_smr(void *);
void bpf_d_smr(void *);
/*
* Reference count access to descriptor buffers
*/
void bpf_get(struct bpf_d *);
void bpf_put(struct bpf_d *);
struct rwlock bpf_sysctl_lk = RWLOCK_INITIALIZER("bpfsz");
int
bpf_movein(struct uio *uio, struct bpf_d *d, struct mbuf **mp,
struct sockaddr *sockp)
{
struct bpf_program_smr *bps;
struct bpf_insn *fcode = NULL;
struct mbuf *m;
struct m_tag *mtag;
int error;
u_int hlen;
u_int len;
u_int linktype;
u_int slen;
/*
* Build a sockaddr based on the data link layer type.
* We do this at this level because the ethernet header
* is copied directly into the data field of the sockaddr.
* In the case of SLIP, there is no header and the packet
* is forwarded as is.
* Also, we are careful to leave room at the front of the mbuf
* for the link level header.
*/
linktype = d->bd_bif->bif_dlt;
switch (linktype) {
case DLT_SLIP:
sockp->sa_family = AF_INET;
hlen = 0;
break;
case DLT_PPP:
sockp->sa_family = AF_UNSPEC;
hlen = 0;
break;
case DLT_EN10MB:
sockp->sa_family = AF_UNSPEC;
/* XXX Would MAXLINKHDR be better? */
hlen = ETHER_HDR_LEN;
break;
case DLT_IEEE802_11:
case DLT_IEEE802_11_RADIO:
sockp->sa_family = AF_UNSPEC;
hlen = 0;
break;
case DLT_RAW:
case DLT_NULL:
sockp->sa_family = AF_UNSPEC;
hlen = 0;
break;
case DLT_LOOP:
sockp->sa_family = AF_UNSPEC;
hlen = sizeof(u_int32_t);
break;
default:
return (EIO);
}
if (uio->uio_resid > MAXMCLBYTES)
return (EIO);
len = uio->uio_resid;
MGETHDR(m, M_WAIT, MT_DATA);
m->m_pkthdr.ph_ifidx = 0;
m->m_pkthdr.len = len - hlen;
if (len > MHLEN) {
MCLGETL(m, M_WAIT, len);
if ((m->m_flags & M_EXT) == 0) {
error = ENOBUFS;
goto bad;
}
}
m->m_len = len;
*mp = m;
error = uiomove(mtod(m, caddr_t), len, uio);
if (error)
goto bad;
smr_read_enter();
bps = SMR_PTR_GET(&d->bd_wfilter);
if (bps != NULL)
fcode = bps->bps_bf.bf_insns;
slen = bpf_filter(fcode, mtod(m, u_char *), len, len);
smr_read_leave();
if (slen < len) {
error = EPERM;
goto bad;
}
if (m->m_len < hlen) {
error = EPERM;
goto bad;
}
/*
* Make room for link header, and copy it to sockaddr
*/
if (hlen != 0) {
if (linktype == DLT_LOOP) {
u_int32_t af;
/* the link header indicates the address family */
KASSERT(hlen == sizeof(u_int32_t));
memcpy(&af, m->m_data, hlen);
sockp->sa_family = ntohl(af);
} else
memcpy(sockp->sa_data, m->m_data, hlen);
m->m_len -= hlen;
m->m_data += hlen; /* XXX */
}
/*
* Prepend the data link type as a mbuf tag
*/
mtag = m_tag_get(PACKET_TAG_DLT, sizeof(u_int), M_WAIT);
*(u_int *)(mtag + 1) = linktype;
m_tag_prepend(m, mtag);
return (0);
bad:
m_freem(m);
return (error);
}
/*
* Attach file to the bpf interface, i.e. make d listen on bp.
*/
void
bpf_attachd(struct bpf_d *d, struct bpf_if *bp)
{
MUTEX_ASSERT_LOCKED(&d->bd_mtx);
/*
* Point d at bp, and add d to the interface's list of listeners.
* Finally, point the driver's bpf cookie at the interface so
* it will divert packets to bpf.
*/
d->bd_bif = bp;
KERNEL_ASSERT_LOCKED();
SMR_SLIST_INSERT_HEAD_LOCKED(&bp->bif_dlist, d, bd_next);
*bp->bif_driverp = bp;
}
/*
* Detach a file from its interface.
*/
void
bpf_detachd(struct bpf_d *d)
{
struct bpf_if *bp;
MUTEX_ASSERT_LOCKED(&d->bd_mtx);
bp = d->bd_bif;
/* Not attached. */
if (bp == NULL)
return;
/* Remove ``d'' from the interface's descriptor list. */
KERNEL_ASSERT_LOCKED();
SMR_SLIST_REMOVE_LOCKED(&bp->bif_dlist, d, bpf_d, bd_next);
if (SMR_SLIST_EMPTY_LOCKED(&bp->bif_dlist)) {
/*
* Let the driver know that there are no more listeners.
*/
*bp->bif_driverp = NULL;
}
d->bd_bif = NULL;
/*
* Check if this descriptor had requested promiscuous mode.
* If so, turn it off.
*/
if (d->bd_promisc) {
int error;
KASSERT(bp->bif_ifp != NULL);
d->bd_promisc = 0;
bpf_get(d);
mtx_leave(&d->bd_mtx);
NET_LOCK();
error = ifpromisc(bp->bif_ifp, 0);
NET_UNLOCK();
mtx_enter(&d->bd_mtx);
bpf_put(d);
if (error && !(error == EINVAL || error == ENODEV ||
error == ENXIO))
/*
* Something is really wrong if we were able to put
* the driver into promiscuous mode, but can't
* take it out.
*/
panic("bpf: ifpromisc failed");
}
}
void
bpfilterattach(int n)
{
LIST_INIT(&bpf_d_list);
}
/*
* Open ethernet device. Returns ENXIO for illegal minor device number,
* EBUSY if file is open by another process.
*/
int
bpfopen(dev_t dev, int flag, int mode, struct proc *p)
{
struct bpf_d *bd;
int unit = minor(dev);
if (unit & ((1 << CLONE_SHIFT) - 1))
return (ENXIO);
KASSERT(bpfilter_lookup(unit) == NULL);
/* create on demand */
if ((bd = malloc(sizeof(*bd), M_DEVBUF, M_NOWAIT|M_ZERO)) == NULL)
return (EBUSY);
/* Mark "free" and do most initialization. */
bd->bd_unit = unit;
bd->bd_bufsize = bpf_bufsize;
bd->bd_sig = SIGIO;
mtx_init(&bd->bd_mtx, IPL_NET);
task_set(&bd->bd_wake_task, bpf_wakeup_cb, bd);
smr_init(&bd->bd_smr);
sigio_init(&bd->bd_sigio);
bd->bd_rtout = 0; /* no timeout by default */
bpf_get(bd);
LIST_INSERT_HEAD(&bpf_d_list, bd, bd_list);
return (0);
}
/*
* Close the descriptor by detaching it from its interface,
* deallocating its buffers, and marking it free.
*/
int
bpfclose(dev_t dev, int flag, int mode, struct proc *p)
{
struct bpf_d *d;
d = bpfilter_lookup(minor(dev));
mtx_enter(&d->bd_mtx);
bpf_detachd(d);
bpf_wakeup(d);
LIST_REMOVE(d, bd_list);
mtx_leave(&d->bd_mtx);
bpf_put(d);
return (0);
}
/*
* Rotate the packet buffers in descriptor d. Move the store buffer
* into the hold slot, and the free buffer into the store slot.
* Zero the length of the new store buffer.
*/
#define ROTATE_BUFFERS(d) \
KASSERT(d->bd_in_uiomove == 0); \
MUTEX_ASSERT_LOCKED(&d->bd_mtx); \
(d)->bd_hbuf = (d)->bd_sbuf; \
(d)->bd_hlen = (d)->bd_slen; \
(d)->bd_sbuf = (d)->bd_fbuf; \
(d)->bd_slen = 0; \
(d)->bd_fbuf = NULL;
/*
* TODO Move nsecuptime() into kern_tc.c and document it when we have
* more users elsewhere in the kernel.
*/
static uint64_t
nsecuptime(void)
{
struct timespec now;
nanouptime(&now);
return TIMESPEC_TO_NSEC(&now);
}
/*
* bpfread - read next chunk of packets from buffers
*/
int
bpfread(dev_t dev, struct uio *uio, int ioflag)
{
uint64_t end, now;
struct bpf_d *d;
caddr_t hbuf;
int error, hlen;
KERNEL_ASSERT_LOCKED();
d = bpfilter_lookup(minor(dev));
if (d->bd_bif == NULL)
return (ENXIO);
bpf_get(d);
mtx_enter(&d->bd_mtx);
/*
* Restrict application to use a buffer the same size as
* as kernel buffers.
*/
if (uio->uio_resid != d->bd_bufsize) {
error = EINVAL;
goto out;
}
/*
* If there's a timeout, mark when the read should end.
*/
if (d->bd_rtout != 0) {
now = nsecuptime();
end = now + d->bd_rtout;
if (end < now)
end = UINT64_MAX;
}
/*
* If the hold buffer is empty, then do a timed sleep, which
* ends when the timeout expires or when enough packets
* have arrived to fill the store buffer.
*/
while (d->bd_hbuf == NULL) {
if (d->bd_bif == NULL) {
/* interface is gone */
if (d->bd_slen == 0) {
error = EIO;
goto out;
}
ROTATE_BUFFERS(d);
break;
}
if (d->bd_immediate && d->bd_slen != 0) {
/*
* A packet(s) either arrived since the previous
* read or arrived while we were asleep.
* Rotate the buffers and return what's here.
*/
ROTATE_BUFFERS(d);
break;
}
if (ISSET(ioflag, IO_NDELAY)) {
/* User requested non-blocking I/O */
error = EWOULDBLOCK;
} else if (d->bd_rtout == 0) {
/* No read timeout set. */
d->bd_nreaders++;
error = msleep_nsec(d, &d->bd_mtx, PRINET|PCATCH,
"bpf", INFSLP);
d->bd_nreaders--;
} else if ((now = nsecuptime()) < end) {
/* Read timeout has not expired yet. */
d->bd_nreaders++;
error = msleep_nsec(d, &d->bd_mtx, PRINET|PCATCH,
"bpf", end - now);
d->bd_nreaders--;
} else {
/* Read timeout has expired. */
error = EWOULDBLOCK;
}
if (error == EINTR || error == ERESTART)
goto out;
if (error == EWOULDBLOCK) {
/*
* On a timeout, return what's in the buffer,
* which may be nothing. If there is something
* in the store buffer, we can rotate the buffers.
*/
if (d->bd_hbuf != NULL)
/*
* We filled up the buffer in between
* getting the timeout and arriving
* here, so we don't need to rotate.
*/
break;
if (d->bd_slen == 0) {
error = 0;
goto out;
}
ROTATE_BUFFERS(d);
break;
}
}
/*
* At this point, we know we have something in the hold slot.
*/
hbuf = d->bd_hbuf;
hlen = d->bd_hlen;
d->bd_hbuf = NULL;
d->bd_hlen = 0;
d->bd_fbuf = NULL;
d->bd_in_uiomove = 1;
/*
* Move data from hold buffer into user space.
* We know the entire buffer is transferred since
* we checked above that the read buffer is bpf_bufsize bytes.
*/
mtx_leave(&d->bd_mtx);
error = uiomove(hbuf, hlen, uio);
mtx_enter(&d->bd_mtx);
/* Ensure that bpf_resetd() or ROTATE_BUFFERS() haven't been called. */
KASSERT(d->bd_fbuf == NULL);
KASSERT(d->bd_hbuf == NULL);
d->bd_fbuf = hbuf;
d->bd_in_uiomove = 0;
out:
mtx_leave(&d->bd_mtx);
bpf_put(d);
return (error);
}
/*
* If there are processes sleeping on this descriptor, wake them up.
*/
void
bpf_wakeup(struct bpf_d *d)
{
MUTEX_ASSERT_LOCKED(&d->bd_mtx);
if (d->bd_nreaders)
wakeup(d);
/*
* As long as pgsigio() and selwakeup() need to be protected
* by the KERNEL_LOCK() we have to delay the wakeup to
* another context to keep the hot path KERNEL_LOCK()-free.
*/
if ((d->bd_async && d->bd_sig) ||
(!klist_empty(&d->bd_sel.si_note) || d->bd_sel.si_seltid != 0)) {
bpf_get(d);
if (!task_add(systq, &d->bd_wake_task))
bpf_put(d);
}
}
void
bpf_wakeup_cb(void *xd)
{
struct bpf_d *d = xd;
if (d->bd_async && d->bd_sig)
pgsigio(&d->bd_sigio, d->bd_sig, 0);
selwakeup(&d->bd_sel);
bpf_put(d);
}
int
bpfwrite(dev_t dev, struct uio *uio, int ioflag)
{
struct bpf_d *d;
struct ifnet *ifp;
struct mbuf *m;
int error;
struct sockaddr_storage dst;
KERNEL_ASSERT_LOCKED();
d = bpfilter_lookup(minor(dev));
if (d->bd_bif == NULL)
return (ENXIO);
bpf_get(d);
ifp = d->bd_bif->bif_ifp;
if (ifp == NULL || (ifp->if_flags & IFF_UP) == 0) {
error = ENETDOWN;
goto out;
}
if (uio->uio_resid == 0) {
error = 0;
goto out;
}
error = bpf_movein(uio, d, &m, sstosa(&dst));
if (error)
goto out;
if (m->m_pkthdr.len > ifp->if_mtu) {
m_freem(m);
error = EMSGSIZE;
goto out;
}
m->m_pkthdr.ph_rtableid = ifp->if_rdomain;
m->m_pkthdr.pf.prio = ifp->if_llprio;
if (d->bd_hdrcmplt && dst.ss_family == AF_UNSPEC)
dst.ss_family = pseudo_AF_HDRCMPLT;
NET_LOCK();
error = ifp->if_output(ifp, m, sstosa(&dst), NULL);
NET_UNLOCK();
out:
bpf_put(d);
return (error);
}
/*
* Reset a descriptor by flushing its packet buffer and clearing the
* receive and drop counts.
*/
void
bpf_resetd(struct bpf_d *d)
{
MUTEX_ASSERT_LOCKED(&d->bd_mtx);
KASSERT(d->bd_in_uiomove == 0);
if (d->bd_hbuf != NULL) {
/* Free the hold buffer. */
d->bd_fbuf = d->bd_hbuf;
d->bd_hbuf = NULL;
}
d->bd_slen = 0;
d->bd_hlen = 0;
d->bd_rcount = 0;
d->bd_dcount = 0;
}
/*
* FIONREAD Check for read packet available.
* BIOCGBLEN Get buffer len [for read()].
* BIOCSETF Set ethernet read filter.
* BIOCFLUSH Flush read packet buffer.
* BIOCPROMISC Put interface into promiscuous mode.
* BIOCGDLTLIST Get supported link layer types.
* BIOCGDLT Get link layer type.
* BIOCSDLT Set link layer type.
* BIOCGETIF Get interface name.
* BIOCSETIF Set interface.
* BIOCSRTIMEOUT Set read timeout.
* BIOCGRTIMEOUT Get read timeout.
* BIOCGSTATS Get packet stats.
* BIOCIMMEDIATE Set immediate mode.
* BIOCVERSION Get filter language version.
* BIOCGHDRCMPLT Get "header already complete" flag
* BIOCSHDRCMPLT Set "header already complete" flag
*/
int
bpfioctl(dev_t dev, u_long cmd, caddr_t addr, int flag, struct proc *p)
{
struct bpf_d *d;
int error = 0;
d = bpfilter_lookup(minor(dev));
if (d->bd_locked && suser(p) != 0) {
/* list of allowed ioctls when locked and not root */
switch (cmd) {
case BIOCGBLEN:
case BIOCFLUSH:
case BIOCGDLT:
case BIOCGDLTLIST:
case BIOCGETIF:
case BIOCGRTIMEOUT:
case BIOCGSTATS:
case BIOCVERSION:
case BIOCGRSIG:
case BIOCGHDRCMPLT:
case FIONREAD:
case BIOCLOCK:
case BIOCSRTIMEOUT:
case BIOCIMMEDIATE:
case TIOCGPGRP:
case BIOCGDIRFILT:
break;
default:
return (EPERM);
}
}
bpf_get(d);
switch (cmd) {
default:
error = EINVAL;
break;
/*
* Check for read packet available.
*/
case FIONREAD:
{
int n;
mtx_enter(&d->bd_mtx);
n = d->bd_slen;
if (d->bd_hbuf != NULL)
n += d->bd_hlen;
mtx_leave(&d->bd_mtx);
*(int *)addr = n;
break;
}
/*
* Get buffer len [for read()].
*/
case BIOCGBLEN:
*(u_int *)addr = d->bd_bufsize;
break;
/*
* Set buffer length.
*/
case BIOCSBLEN:
if (d->bd_bif != NULL)
error = EINVAL;
else {
u_int size = *(u_int *)addr;
if (size > bpf_maxbufsize)
*(u_int *)addr = size = bpf_maxbufsize;
else if (size < BPF_MINBUFSIZE)
*(u_int *)addr = size = BPF_MINBUFSIZE;
mtx_enter(&d->bd_mtx);
d->bd_bufsize = size;
mtx_leave(&d->bd_mtx);
}
break;
/*
* Set link layer read filter.
*/
case BIOCSETF:
error = bpf_setf(d, (struct bpf_program *)addr, 0);
break;
/*
* Set link layer write filter.
*/
case BIOCSETWF:
error = bpf_setf(d, (struct bpf_program *)addr, 1);
break;
/*
* Flush read packet buffer.
*/
case BIOCFLUSH:
mtx_enter(&d->bd_mtx);
bpf_resetd(d);
mtx_leave(&d->bd_mtx);
break;
/*
* Put interface into promiscuous mode.
*/
case BIOCPROMISC:
if (d->bd_bif == NULL) {
/*
* No interface attached yet.
*/
error = EINVAL;
} else if (d->bd_bif->bif_ifp != NULL) {
if (d->bd_promisc == 0) {
MUTEX_ASSERT_UNLOCKED(&d->bd_mtx);
NET_LOCK();
error = ifpromisc(d->bd_bif->bif_ifp, 1);
NET_UNLOCK();
if (error == 0)
d->bd_promisc = 1;
}
}
break;
/*
* Get a list of supported device parameters.
*/
case BIOCGDLTLIST:
if (d->bd_bif == NULL)
error = EINVAL;
else
error = bpf_getdltlist(d, (struct bpf_dltlist *)addr);
break;
/*
* Get device parameters.
*/
case BIOCGDLT:
if (d->bd_bif == NULL)
error = EINVAL;
else
*(u_int *)addr = d->bd_bif->bif_dlt;
break;
/*
* Set device parameters.
*/
case BIOCSDLT:
if (d->bd_bif == NULL)
error = EINVAL;
else {
mtx_enter(&d->bd_mtx);
error = bpf_setdlt(d, *(u_int *)addr);
mtx_leave(&d->bd_mtx);
}
break;
/*
* Set interface name.
*/
case BIOCGETIF:
if (d->bd_bif == NULL)
error = EINVAL;
else
bpf_ifname(d->bd_bif, (struct ifreq *)addr);
break;
/*
* Set interface.
*/
case BIOCSETIF:
error = bpf_setif(d, (struct ifreq *)addr);
break;
/*
* Set read timeout.
*/
case BIOCSRTIMEOUT:
{
struct timeval *tv = (struct timeval *)addr;
uint64_t rtout;
if (tv->tv_sec < 0 || !timerisvalid(tv)) {
error = EINVAL;
break;
}
rtout = TIMEVAL_TO_NSEC(tv);
if (rtout > MAXTSLP) {
error = EOVERFLOW;
break;
}
mtx_enter(&d->bd_mtx);
d->bd_rtout = rtout;
mtx_leave(&d->bd_mtx);
break;
}
/*
* Get read timeout.
*/
case BIOCGRTIMEOUT:
{
struct timeval *tv = (struct timeval *)addr;
memset(tv, 0, sizeof(*tv));
mtx_enter(&d->bd_mtx);
NSEC_TO_TIMEVAL(d->bd_rtout, tv);
mtx_leave(&d->bd_mtx);
break;
}
/*
* Get packet stats.
*/
case BIOCGSTATS:
{
struct bpf_stat *bs = (struct bpf_stat *)addr;
bs->bs_recv = d->bd_rcount;
bs->bs_drop = d->bd_dcount;
break;
}
/*
* Set immediate mode.
*/
case BIOCIMMEDIATE:
d->bd_immediate = *(u_int *)addr;
break;
case BIOCVERSION:
{
struct bpf_version *bv = (struct bpf_version *)addr;
bv->bv_major = BPF_MAJOR_VERSION;
bv->bv_minor = BPF_MINOR_VERSION;
break;
}
case BIOCGHDRCMPLT: /* get "header already complete" flag */
*(u_int *)addr = d->bd_hdrcmplt;
break;
case BIOCSHDRCMPLT: /* set "header already complete" flag */
d->bd_hdrcmplt = *(u_int *)addr ? 1 : 0;
break;
case BIOCLOCK: /* set "locked" flag (no reset) */
d->bd_locked = 1;
break;
case BIOCGFILDROP: /* get "filter-drop" flag */
*(u_int *)addr = d->bd_fildrop;
break;
case BIOCSFILDROP: { /* set "filter-drop" flag */
unsigned int fildrop = *(u_int *)addr;
switch (fildrop) {
case BPF_FILDROP_PASS:
case BPF_FILDROP_CAPTURE:
case BPF_FILDROP_DROP:
d->bd_fildrop = fildrop;
break;
default:
error = EINVAL;
break;
}
break;
}
case BIOCGDIRFILT: /* get direction filter */
*(u_int *)addr = d->bd_dirfilt;
break;
case BIOCSDIRFILT: /* set direction filter */
d->bd_dirfilt = (*(u_int *)addr) &
(BPF_DIRECTION_IN|BPF_DIRECTION_OUT);
break;
case FIONBIO: /* Non-blocking I/O */
/* let vfs to keep track of this */
break;
case FIOASYNC: /* Send signal on receive packets */
d->bd_async = *(int *)addr;
break;
case FIOSETOWN: /* Process or group to send signals to */
case TIOCSPGRP:
error = sigio_setown(&d->bd_sigio, cmd, addr);
break;
case FIOGETOWN:
case TIOCGPGRP:
sigio_getown(&d->bd_sigio, cmd, addr);
break;