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freebsd-nq/sys/net/bpf.c
Christian S.J. Peron 93e39f0b93 Introduce two new ioctl(2) commands, BIOCLOCK and BIOCSETWF. These commands 
enhance the security of bpf(4) by further relinquishing the privilege of
the bpf(4) consumer (assuming the ioctl commands are being implemented).

Once BIOCLOCK is executed, the device becomes locked which prevents the
execution of ioctl(2) commands which can change the underly parameters of the
bpf(4) device. An example might be the setting of bpf(4) filter programs or
attaching to different network interfaces.

BIOCSETWF can be used to set write filters for outgoing packets. Currently if
a bpf(4) consumer is compromised, the bpf(4) descriptor can essentially be used
as a raw socket, regardless of consumer's UID. Write filters give users the
ability to constrain which packets can be sent through the bpf(4) descriptor.

These features are currently implemented by a couple programs which came from
OpenBSD, such as the new dhclient and pflogd.

-Modify bpf_setf(9) to accept a "cmd" parameter. This will be used to specify
 whether a read or write filter is to be set.
-Add a bpf(4) filter program as a parameter to bpf_movein(9) as we will run the
 filter program on the mbuf data once we move the packet in from user-space.
-Rather than execute two uiomove operations, (one for the link header and the
 other for the packet data), execute one and manually copy the linker header
 into the sockaddr structure via bcopy.
-Restructure bpf_setf to compensate for write filters, as well as read.
-Adjust bpf(4) stats structures to include a bd_locked member.

It should be noted that the FreeBSD and OpenBSD implementations differ a bit in
the sense that we unconditionally enforce the lock, where OpenBSD enforces it
only if the calling credential is not root.

Idea from:	OpenBSD
Reviewed by:	mlaier
2005-08-22 19:35:48 +00:00

1848 lines
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/*-
* Copyright (c) 1990, 1991, 1993
* The Regents of the University of California. All rights reserved.
*
* 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.
* 4. 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 8.4 (Berkeley) 1/9/95
*
* $FreeBSD$
*/
#include "opt_bpf.h"
#include "opt_mac.h"
#include "opt_netgraph.h"
#include <sys/types.h>
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/conf.h>
#include <sys/fcntl.h>
#include <sys/mac.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
#include <sys/time.h>
#include <sys/proc.h>
#include <sys/signalvar.h>
#include <sys/filio.h>
#include <sys/sockio.h>
#include <sys/ttycom.h>
#include <sys/uio.h>
#include <sys/event.h>
#include <sys/file.h>
#include <sys/poll.h>
#include <sys/proc.h>
#include <sys/socket.h>
#include <net/if.h>
#include <net/bpf.h>
#include <net/bpfdesc.h>
#include <netinet/in.h>
#include <netinet/if_ether.h>
#include <sys/kernel.h>
#include <sys/sysctl.h>
static MALLOC_DEFINE(M_BPF, "BPF", "BPF data");
#if defined(DEV_BPF) || defined(NETGRAPH_BPF)
#define PRINET 26 /* interruptible */
/*
* bpf_iflist is a list of BPF interface structures, each corresponding to a
* specific DLT. The same network interface might have several BPF interface
* structures registered by different layers in the stack (i.e., 802.11
* frames, ethernet frames, etc).
*/
static LIST_HEAD(, bpf_if) bpf_iflist;
static struct mtx bpf_mtx; /* bpf global lock */
static int bpf_bpfd_cnt;
static int bpf_allocbufs(struct bpf_d *);
static void bpf_attachd(struct bpf_d *d, struct bpf_if *bp);
static void bpf_detachd(struct bpf_d *d);
static void bpf_freed(struct bpf_d *);
static void bpf_mcopy(const void *, void *, size_t);
static int bpf_movein(struct uio *, int, int,
struct mbuf **, struct sockaddr *, struct bpf_insn *);
static int bpf_setif(struct bpf_d *, struct ifreq *);
static void bpf_timed_out(void *);
static __inline void
bpf_wakeup(struct bpf_d *);
static void catchpacket(struct bpf_d *, u_char *, u_int,
u_int, void (*)(const void *, void *, size_t));
static void reset_d(struct bpf_d *);
static int bpf_setf(struct bpf_d *, struct bpf_program *, u_long cmd);
static int bpf_getdltlist(struct bpf_d *, struct bpf_dltlist *);
static int bpf_setdlt(struct bpf_d *, u_int);
static void filt_bpfdetach(struct knote *);
static int filt_bpfread(struct knote *, long);
static void bpf_drvinit(void *);
static void bpf_clone(void *, struct ucred *, char *, int, struct cdev **);
static int bpf_stats_sysctl(SYSCTL_HANDLER_ARGS);
/*
* The default read buffer size is patchable.
*/
SYSCTL_NODE(_net, OID_AUTO, bpf, CTLFLAG_RW, 0, "bpf sysctl");
static int bpf_bufsize = 4096;
SYSCTL_INT(_net_bpf, OID_AUTO, bufsize, CTLFLAG_RW,
&bpf_bufsize, 0, "");
static int bpf_maxbufsize = BPF_MAXBUFSIZE;
SYSCTL_INT(_net_bpf, OID_AUTO, maxbufsize, CTLFLAG_RW,
&bpf_maxbufsize, 0, "");
static int bpf_maxinsns = BPF_MAXINSNS;
SYSCTL_INT(_net_bpf, OID_AUTO, maxinsns, CTLFLAG_RW,
&bpf_maxinsns, 0, "Maximum bpf program instructions");
SYSCTL_NODE(_net_bpf, OID_AUTO, stats, CTLFLAG_RW,
bpf_stats_sysctl, "bpf statistics portal");
static d_open_t bpfopen;
static d_close_t bpfclose;
static d_read_t bpfread;
static d_write_t bpfwrite;
static d_ioctl_t bpfioctl;
static d_poll_t bpfpoll;
static d_kqfilter_t bpfkqfilter;
static struct cdevsw bpf_cdevsw = {
.d_version = D_VERSION,
.d_flags = D_NEEDGIANT,
.d_open = bpfopen,
.d_close = bpfclose,
.d_read = bpfread,
.d_write = bpfwrite,
.d_ioctl = bpfioctl,
.d_poll = bpfpoll,
.d_name = "bpf",
.d_kqfilter = bpfkqfilter,
};
static struct filterops bpfread_filtops =
{ 1, NULL, filt_bpfdetach, filt_bpfread };
static int
bpf_movein(uio, linktype, mtu, mp, sockp, wfilter)
struct uio *uio;
int linktype;
int mtu;
struct mbuf **mp;
struct sockaddr *sockp;
struct bpf_insn *wfilter;
{
struct mbuf *m;
int error;
int len;
int hlen;
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.
*/
switch (linktype) {
case DLT_SLIP:
sockp->sa_family = AF_INET;
hlen = 0;
break;
case DLT_EN10MB:
sockp->sa_family = AF_UNSPEC;
/* XXX Would MAXLINKHDR be better? */
hlen = ETHER_HDR_LEN;
break;
case DLT_FDDI:
sockp->sa_family = AF_IMPLINK;
hlen = 0;
break;
case DLT_RAW:
sockp->sa_family = AF_UNSPEC;
hlen = 0;
break;
case DLT_NULL:
/*
* null interface types require a 4 byte pseudo header which
* corresponds to the address family of the packet.
*/
sockp->sa_family = AF_UNSPEC;
hlen = 4;
break;
case DLT_ATM_RFC1483:
/*
* en atm driver requires 4-byte atm pseudo header.
* though it isn't standard, vpi:vci needs to be
* specified anyway.
*/
sockp->sa_family = AF_UNSPEC;
hlen = 12; /* XXX 4(ATM_PH) + 3(LLC) + 5(SNAP) */
break;
case DLT_PPP:
sockp->sa_family = AF_UNSPEC;
hlen = 4; /* This should match PPP_HDRLEN */
break;
default:
return (EIO);
}
len = uio->uio_resid;
if (len - hlen > mtu)
return (EMSGSIZE);
if ((unsigned)len > MCLBYTES)
return (EIO);
if (len > MHLEN) {
m = m_getcl(M_TRYWAIT, MT_DATA, M_PKTHDR);
} else {
MGETHDR(m, M_TRYWAIT, MT_DATA);
}
if (m == NULL)
return (ENOBUFS);
m->m_pkthdr.len = m->m_len = len;
m->m_pkthdr.rcvif = NULL;
*mp = m;
if (m->m_len < hlen) {
error = EPERM;
goto bad;
}
error = uiomove(mtod(m, u_char *), len, uio);
if (error)
goto bad;
slen = bpf_filter(wfilter, mtod(m, u_char *), len, len);
if (slen == 0) {
error = EPERM;
goto bad;
}
/*
* Make room for link header, and copy it to sockaddr
*/
if (hlen != 0) {
bcopy(m->m_data, sockp->sa_data, hlen);
m->m_pkthdr.len -= hlen;
m->m_len -= hlen;
#if BSD >= 199103
m->m_data += hlen; /* XXX */
#else
m->m_off += hlen;
#endif
}
return (0);
bad:
m_freem(m);
return (error);
}
/*
* Attach file to the bpf interface, i.e. make d listen on bp.
*/
static void
bpf_attachd(d, bp)
struct bpf_d *d;
struct bpf_if *bp;
{
/*
* 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.
*/
BPFIF_LOCK(bp);
d->bd_bif = bp;
LIST_INSERT_HEAD(&bp->bif_dlist, d, bd_next);
bpf_bpfd_cnt++;
*bp->bif_driverp = bp;
BPFIF_UNLOCK(bp);
}
/*
* Detach a file from its interface.
*/
static void
bpf_detachd(d)
struct bpf_d *d;
{
int error;
struct bpf_if *bp;
struct ifnet *ifp;
bp = d->bd_bif;
BPFIF_LOCK(bp);
BPFD_LOCK(d);
ifp = d->bd_bif->bif_ifp;
/*
* Remove d from the interface's descriptor list.
*/
LIST_REMOVE(d, bd_next);
bpf_bpfd_cnt--;
/*
* Let the driver know that there are no more listeners.
*/
if (LIST_EMPTY(&bp->bif_dlist))
*bp->bif_driverp = NULL;
d->bd_bif = NULL;
BPFD_UNLOCK(d);
BPFIF_UNLOCK(bp);
/*
* Check if this descriptor had requested promiscuous mode.
* If so, turn it off.
*/
if (d->bd_promisc) {
d->bd_promisc = 0;
error = ifpromisc(ifp, 0);
if (error != 0 && error != ENXIO) {
/*
* ENXIO can happen if a pccard is unplugged
* Something is really wrong if we were able to put
* the driver into promiscuous mode, but can't
* take it out.
*/
if_printf(bp->bif_ifp,
"bpf_detach: ifpromisc failed (%d)\n", error);
}
}
}
/*
* Open ethernet device. Returns ENXIO for illegal minor device number,
* EBUSY if file is open by another process.
*/
/* ARGSUSED */
static int
bpfopen(dev, flags, fmt, td)
struct cdev *dev;
int flags;
int fmt;
struct thread *td;
{
struct bpf_d *d;
mtx_lock(&bpf_mtx);
d = dev->si_drv1;
/*
* Each minor can be opened by only one process. If the requested
* minor is in use, return EBUSY.
*/
if (d != NULL) {
mtx_unlock(&bpf_mtx);
return (EBUSY);
}
dev->si_drv1 = (struct bpf_d *)~0; /* mark device in use */
mtx_unlock(&bpf_mtx);
if ((dev->si_flags & SI_NAMED) == 0)
make_dev(&bpf_cdevsw, minor(dev), UID_ROOT, GID_WHEEL, 0600,
"bpf%d", dev2unit(dev));
MALLOC(d, struct bpf_d *, sizeof(*d), M_BPF, M_WAITOK | M_ZERO);
dev->si_drv1 = d;
d->bd_bufsize = bpf_bufsize;
d->bd_sig = SIGIO;
d->bd_seesent = 1;
d->bd_pid = td->td_proc->p_pid;
strlcpy(d->bd_pcomm, td->td_proc->p_comm, MAXCOMLEN);
#ifdef MAC
mac_init_bpfdesc(d);
mac_create_bpfdesc(td->td_ucred, d);
#endif
mtx_init(&d->bd_mtx, devtoname(dev), "bpf cdev lock", MTX_DEF);
callout_init(&d->bd_callout, NET_CALLOUT_MPSAFE);
knlist_init(&d->bd_sel.si_note, &d->bd_mtx, NULL, NULL, NULL);
return (0);
}
/*
* Close the descriptor by detaching it from its interface,
* deallocating its buffers, and marking it free.
*/
/* ARGSUSED */
static int
bpfclose(dev, flags, fmt, td)
struct cdev *dev;
int flags;
int fmt;
struct thread *td;
{
struct bpf_d *d = dev->si_drv1;
BPFD_LOCK(d);
if (d->bd_state == BPF_WAITING)
callout_stop(&d->bd_callout);
d->bd_state = BPF_IDLE;
BPFD_UNLOCK(d);
funsetown(&d->bd_sigio);
mtx_lock(&bpf_mtx);
if (d->bd_bif)
bpf_detachd(d);
mtx_unlock(&bpf_mtx);
selwakeuppri(&d->bd_sel, PRINET);
#ifdef MAC
mac_destroy_bpfdesc(d);
#endif /* MAC */
knlist_destroy(&d->bd_sel.si_note);
bpf_freed(d);
dev->si_drv1 = NULL;
free(d, M_BPF);
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) \
(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;
/*
* bpfread - read next chunk of packets from buffers
*/
static int
bpfread(dev, uio, ioflag)
struct cdev *dev;
struct uio *uio;
int ioflag;
{
struct bpf_d *d = dev->si_drv1;
int timed_out;
int error;
/*
* Restrict application to use a buffer the same size as
* as kernel buffers.
*/
if (uio->uio_resid != d->bd_bufsize)
return (EINVAL);
BPFD_LOCK(d);
if (d->bd_state == BPF_WAITING)
callout_stop(&d->bd_callout);
timed_out = (d->bd_state == BPF_TIMED_OUT);
d->bd_state = BPF_IDLE;
/*
* 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_immediate || timed_out) && 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;
}
/*
* No data is available, check to see if the bpf device
* is still pointed at a real interface. If not, return
* ENXIO so that the userland process knows to rebind
* it before using it again.
*/
if (d->bd_bif == NULL) {
BPFD_UNLOCK(d);
return (ENXIO);
}
if (ioflag & O_NONBLOCK) {
BPFD_UNLOCK(d);
return (EWOULDBLOCK);
}
error = msleep(d, &d->bd_mtx, PRINET|PCATCH,
"bpf", d->bd_rtout);
if (error == EINTR || error == ERESTART) {
BPFD_UNLOCK(d);
return (error);
}
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)
/*
* 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) {
BPFD_UNLOCK(d);
return (0);
}
ROTATE_BUFFERS(d);
break;
}
}
/*
* At this point, we know we have something in the hold slot.
*/
BPFD_UNLOCK(d);
/*
* 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.
*/
error = uiomove(d->bd_hbuf, d->bd_hlen, uio);
BPFD_LOCK(d);
d->bd_fbuf = d->bd_hbuf;
d->bd_hbuf = NULL;
d->bd_hlen = 0;
BPFD_UNLOCK(d);
return (error);
}
/*
* If there are processes sleeping on this descriptor, wake them up.
*/
static __inline void
bpf_wakeup(d)
struct bpf_d *d;
{
BPFD_LOCK_ASSERT(d);
if (d->bd_state == BPF_WAITING) {
callout_stop(&d->bd_callout);
d->bd_state = BPF_IDLE;
}
wakeup(d);
if (d->bd_async && d->bd_sig && d->bd_sigio)
pgsigio(&d->bd_sigio, d->bd_sig, 0);
selwakeuppri(&d->bd_sel, PRINET);
KNOTE_LOCKED(&d->bd_sel.si_note, 0);
}
static void
bpf_timed_out(arg)
void *arg;
{
struct bpf_d *d = (struct bpf_d *)arg;
BPFD_LOCK(d);
if (d->bd_state == BPF_WAITING) {
d->bd_state = BPF_TIMED_OUT;
if (d->bd_slen != 0)
bpf_wakeup(d);
}
BPFD_UNLOCK(d);
}
static int
bpfwrite(dev, uio, ioflag)
struct cdev *dev;
struct uio *uio;
int ioflag;
{
struct bpf_d *d = dev->si_drv1;
struct ifnet *ifp;
struct mbuf *m;
int error;
struct sockaddr dst;
if (d->bd_bif == NULL)
return (ENXIO);
ifp = d->bd_bif->bif_ifp;
if ((ifp->if_flags & IFF_UP) == 0)
return (ENETDOWN);
if (uio->uio_resid == 0)
return (0);
bzero(&dst, sizeof(dst));
error = bpf_movein(uio, (int)d->bd_bif->bif_dlt, ifp->if_mtu,
&m, &dst, d->bd_wfilter);
if (error)
return (error);
if (d->bd_hdrcmplt)
dst.sa_family = pseudo_AF_HDRCMPLT;
#ifdef MAC
BPFD_LOCK(d);
mac_create_mbuf_from_bpfdesc(d, m);
BPFD_UNLOCK(d);
#endif
NET_LOCK_GIANT();
error = (*ifp->if_output)(ifp, m, &dst, NULL);
NET_UNLOCK_GIANT();
/*
* The driver frees the mbuf.
*/
return (error);
}
/*
* Reset a descriptor by flushing its packet buffer and clearing the
* receive and drop counts.
*/
static void
reset_d(d)
struct bpf_d *d;
{
mtx_assert(&d->bd_mtx, MA_OWNED);
if (d->bd_hbuf) {
/* 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;
d->bd_fcount = 0;
}
/*
* FIONREAD Check for read packet available.
* SIOCGIFADDR Get interface address - convenient hook to driver.
* BIOCGBLEN Get buffer len [for read()].
* BIOCSETF Set ethernet read filter.
* BIOCSETWF Set ethernet write filter.
* BIOCFLUSH Flush read packet buffer.
* BIOCPROMISC Put interface into promiscuous mode.
* BIOCGDLT Get 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
* BIOCGSEESENT Get "see packets sent" flag
* BIOCSSEESENT Set "see packets sent" flag
* BIOCLOCK Set "locked" flag
*/
/* ARGSUSED */
static int
bpfioctl(dev, cmd, addr, flags, td)
struct cdev *dev;
u_long cmd;
caddr_t addr;
int flags;
struct thread *td;
{
struct bpf_d *d = dev->si_drv1;
int error = 0;
BPFD_LOCK(d);
if (d->bd_state == BPF_WAITING)
callout_stop(&d->bd_callout);
d->bd_state = BPF_IDLE;
BPFD_UNLOCK(d);
if (d->bd_locked == 1) {
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:
break;
default:
return (EPERM);
}
}
switch (cmd) {
default:
error = EINVAL;
break;
/*
* Check for read packet available.
*/
case FIONREAD:
{
int n;
BPFD_LOCK(d);
n = d->bd_slen;
if (d->bd_hbuf)
n += d->bd_hlen;
BPFD_UNLOCK(d);
*(int *)addr = n;
break;
}
case SIOCGIFADDR:
{
struct ifnet *ifp;
if (d->bd_bif == NULL)
error = EINVAL;
else {
ifp = d->bd_bif->bif_ifp;
error = (*ifp->if_ioctl)(ifp, cmd, addr);
}
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;
d->bd_bufsize = size;
}
break;
/*
* Set link layer read filter.
*/
case BIOCSETF:
case BIOCSETWF:
error = bpf_setf(d, (struct bpf_program *)addr, cmd);
break;
/*
* Flush read packet buffer.
*/
case BIOCFLUSH:
BPFD_LOCK(d);
reset_d(d);
BPFD_UNLOCK(d);
break;
/*
* Put interface into promiscuous mode.
*/
case BIOCPROMISC:
if (d->bd_bif == NULL) {
/*
* No interface attached yet.
*/
error = EINVAL;
break;
}
if (d->bd_promisc == 0) {
mtx_lock(&Giant);
error = ifpromisc(d->bd_bif->bif_ifp, 1);
mtx_unlock(&Giant);
if (error == 0)
d->bd_promisc = 1;
}
break;
/*
* Get current data link type.
*/
case BIOCGDLT:
if (d->bd_bif == NULL)
error = EINVAL;
else
*(u_int *)addr = d->bd_bif->bif_dlt;
break;
/*
* Get a list of supported data link types.
*/
case BIOCGDLTLIST:
if (d->bd_bif == NULL)
error = EINVAL;
else
error = bpf_getdltlist(d, (struct bpf_dltlist *)addr);
break;
/*
* Set data link type.
*/
case BIOCSDLT:
if (d->bd_bif == NULL)
error = EINVAL;
else
error = bpf_setdlt(d, *(u_int *)addr);
break;
/*
* Get interface name.
*/
case BIOCGETIF:
if (d->bd_bif == NULL)
error = EINVAL;
else {
struct ifnet *const ifp = d->bd_bif->bif_ifp;
struct ifreq *const ifr = (struct ifreq *)addr;
strlcpy(ifr->ifr_name, ifp->if_xname,
sizeof(ifr->ifr_name));
}
break;
/*
* Set interface.
*/
case BIOCSETIF:
error = bpf_setif(d, (struct ifreq *)addr);
break;
/*
* Set read timeout.
*/
case BIOCSRTIMEOUT:
{
struct timeval *tv = (struct timeval *)addr;
/*
* Subtract 1 tick from tvtohz() since this isn't
* a one-shot timer.
*/
if ((error = itimerfix(tv)) == 0)
d->bd_rtout = tvtohz(tv) - 1;
break;
}
/*
* Get read timeout.
*/
case BIOCGRTIMEOUT:
{
struct timeval *tv = (struct timeval *)addr;
tv->tv_sec = d->bd_rtout / hz;
tv->tv_usec = (d->bd_rtout % hz) * tick;
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;
}
/*
* Get "header already complete" flag
*/
case BIOCGHDRCMPLT:
*(u_int *)addr = d->bd_hdrcmplt;
break;
case BIOCLOCK:
d->bd_locked = 1;
break;
/*
* Set "header already complete" flag
*/
case BIOCSHDRCMPLT:
d->bd_hdrcmplt = *(u_int *)addr ? 1 : 0;
break;
/*
* Get "see sent packets" flag
*/
case BIOCGSEESENT:
*(u_int *)addr = d->bd_seesent;
break;
/*
* Set "see sent packets" flag
*/
case BIOCSSEESENT:
d->bd_seesent = *(u_int *)addr;
break;
case FIONBIO: /* Non-blocking I/O */
break;
case FIOASYNC: /* Send signal on receive packets */
d->bd_async = *(int *)addr;
break;
case FIOSETOWN:
error = fsetown(*(int *)addr, &d->bd_sigio);
break;
case FIOGETOWN:
*(int *)addr = fgetown(&d->bd_sigio);
break;
/* This is deprecated, FIOSETOWN should be used instead. */
case TIOCSPGRP:
error = fsetown(-(*(int *)addr), &d->bd_sigio);
break;
/* This is deprecated, FIOGETOWN should be used instead. */
case TIOCGPGRP:
*(int *)addr = -fgetown(&d->bd_sigio);
break;
case BIOCSRSIG: /* Set receive signal */
{
u_int sig;
sig = *(u_int *)addr;
if (sig >= NSIG)
error = EINVAL;
else
d->bd_sig = sig;
break;
}
case BIOCGRSIG:
*(u_int *)addr = d->bd_sig;
break;
}
return (error);
}
/*
* Set d's packet filter program to fp. If this file already has a filter,
* free it and replace it. Returns EINVAL for bogus requests.
*/
static int
bpf_setf(d, fp, cmd)
struct bpf_d *d;
struct bpf_program *fp;
u_long cmd;
{
struct bpf_insn *fcode, *old;
u_int wfilter, flen, size;
if (cmd == BIOCSETWF) {
old = d->bd_wfilter;
wfilter = 1;
} else {
wfilter = 0;
old = d->bd_rfilter;
}
if (fp->bf_insns == NULL) {
if (fp->bf_len != 0)
return (EINVAL);
BPFD_LOCK(d);
if (wfilter)
d->bd_wfilter = NULL;
else
d->bd_rfilter = NULL;
reset_d(d);
BPFD_UNLOCK(d);
if (old != NULL)
free((caddr_t)old, M_BPF);
return (0);
}
flen = fp->bf_len;
if (flen > bpf_maxinsns)
return (EINVAL);
size = flen * sizeof(*fp->bf_insns);
fcode = (struct bpf_insn *)malloc(size, M_BPF, M_WAITOK);
if (copyin((caddr_t)fp->bf_insns, (caddr_t)fcode, size) == 0 &&
bpf_validate(fcode, (int)flen)) {
BPFD_LOCK(d);
if (wfilter)
d->bd_wfilter = fcode;
else
d->bd_rfilter = fcode;
reset_d(d);
BPFD_UNLOCK(d);
if (old != NULL)
free((caddr_t)old, M_BPF);
return (0);
}
free((caddr_t)fcode, M_BPF);
return (EINVAL);
}
/*
* Detach a file from its current interface (if attached at all) and attach
* to the interface indicated by the name stored in ifr.
* Return an errno or 0.
*/
static int
bpf_setif(d, ifr)
struct bpf_d *d;
struct ifreq *ifr;
{
struct bpf_if *bp;
int error;
struct ifnet *theywant;
theywant = ifunit(ifr->ifr_name);
if (theywant == NULL)
return ENXIO;
/*
* Look through attached interfaces for the named one.
*/
mtx_lock(&bpf_mtx);
LIST_FOREACH(bp, &bpf_iflist, bif_next) {
struct ifnet *ifp = bp->bif_ifp;
if (ifp == NULL || ifp != theywant)
continue;
/* skip additional entry */
if (bp->bif_driverp != &ifp->if_bpf)
continue;
mtx_unlock(&bpf_mtx);
/*
* We found the requested interface.
* Allocate the packet buffers if we need to.
* If we're already attached to requested interface,
* just flush the buffer.
*/
if (d->bd_sbuf == NULL) {
error = bpf_allocbufs(d);
if (error != 0)
return (error);
}
if (bp != d->bd_bif) {
if (d->bd_bif)
/*
* Detach if attached to something else.
*/
bpf_detachd(d);
bpf_attachd(d, bp);
}
BPFD_LOCK(d);
reset_d(d);
BPFD_UNLOCK(d);
return (0);
}
mtx_unlock(&bpf_mtx);
/* Not found. */
return (ENXIO);
}
/*
* Support for select() and poll() system calls
*
* Return true iff the specific operation will not block indefinitely.
* Otherwise, return false but make a note that a selwakeup() must be done.
*/
static int
bpfpoll(dev, events, td)
struct cdev *dev;
int events;
struct thread *td;
{
struct bpf_d *d;
int revents;
d = dev->si_drv1;
if (d->bd_bif == NULL)
return (ENXIO);
revents = events & (POLLOUT | POLLWRNORM);
BPFD_LOCK(d);
if (events & (POLLIN | POLLRDNORM)) {
if (bpf_ready(d))
revents |= events & (POLLIN | POLLRDNORM);
else {
selrecord(td, &d->bd_sel);
/* Start the read timeout if necessary. */
if (d->bd_rtout > 0 && d->bd_state == BPF_IDLE) {
callout_reset(&d->bd_callout, d->bd_rtout,
bpf_timed_out, d);
d->bd_state = BPF_WAITING;
}
}
}
BPFD_UNLOCK(d);
return (revents);
}
/*
* Support for kevent() system call. Register EVFILT_READ filters and
* reject all others.
*/
int
bpfkqfilter(dev, kn)
struct cdev *dev;
struct knote *kn;
{
struct bpf_d *d = (struct bpf_d *)dev->si_drv1;
if (kn->kn_filter != EVFILT_READ)
return (1);
kn->kn_fop = &bpfread_filtops;
kn->kn_hook = d;
knlist_add(&d->bd_sel.si_note, kn, 0);
return (0);
}
static void
filt_bpfdetach(kn)
struct knote *kn;
{
struct bpf_d *d = (struct bpf_d *)kn->kn_hook;
knlist_remove(&d->bd_sel.si_note, kn, 0);
}
static int
filt_bpfread(kn, hint)
struct knote *kn;
long hint;
{
struct bpf_d *d = (struct bpf_d *)kn->kn_hook;
int ready;
BPFD_LOCK_ASSERT(d);
ready = bpf_ready(d);
if (ready) {
kn->kn_data = d->bd_slen;
if (d->bd_hbuf)
kn->kn_data += d->bd_hlen;
}
else if (d->bd_rtout > 0 && d->bd_state == BPF_IDLE) {
callout_reset(&d->bd_callout, d->bd_rtout,
bpf_timed_out, d);
d->bd_state = BPF_WAITING;
}
return (ready);
}
/*
* Incoming linkage from device drivers. Process the packet pkt, of length
* pktlen, which is stored in a contiguous buffer. The packet is parsed
* by each process' filter, and if accepted, stashed into the corresponding
* buffer.
*/
void
bpf_tap(bp, pkt, pktlen)
struct bpf_if *bp;
u_char *pkt;
u_int pktlen;
{
struct bpf_d *d;
u_int slen;
/*
* Lockless read to avoid cost of locking the interface if there are
* no descriptors attached.
*/
if (LIST_EMPTY(&bp->bif_dlist))
return;
BPFIF_LOCK(bp);
LIST_FOREACH(d, &bp->bif_dlist, bd_next) {
BPFD_LOCK(d);
++d->bd_rcount;
slen = bpf_filter(d->bd_rfilter, pkt, pktlen, pktlen);
if (slen != 0) {
d->bd_fcount++;
#ifdef MAC
if (mac_check_bpfdesc_receive(d, bp->bif_ifp) == 0)
#endif
catchpacket(d, pkt, pktlen, slen, bcopy);
}
BPFD_UNLOCK(d);
}
BPFIF_UNLOCK(bp);
}
/*
* Copy data from an mbuf chain into a buffer. This code is derived
* from m_copydata in sys/uipc_mbuf.c.
*/
static void
bpf_mcopy(src_arg, dst_arg, len)
const void *src_arg;
void *dst_arg;
size_t len;
{
const struct mbuf *m;
u_int count;
u_char *dst;
m = src_arg;
dst = dst_arg;
while (len > 0) {
if (m == NULL)
panic("bpf_mcopy");
count = min(m->m_len, len);
bcopy(mtod(m, void *), dst, count);
m = m->m_next;
dst += count;
len -= count;
}
}
/*
* Incoming linkage from device drivers, when packet is in an mbuf chain.
*/
void
bpf_mtap(bp, m)
struct bpf_if *bp;
struct mbuf *m;
{
struct bpf_d *d;
u_int pktlen, slen;
/*
* Lockless read to avoid cost of locking the interface if there are
* no descriptors attached.
*/
if (LIST_EMPTY(&bp->bif_dlist))
return;
pktlen = m_length(m, NULL);
if (pktlen == m->m_len) {
bpf_tap(bp, mtod(m, u_char *), pktlen);
return;
}
BPFIF_LOCK(bp);
LIST_FOREACH(d, &bp->bif_dlist, bd_next) {
if (!d->bd_seesent && (m->m_pkthdr.rcvif == NULL))
continue;
BPFD_LOCK(d);
++d->bd_rcount;
slen = bpf_filter(d->bd_rfilter, (u_char *)m, pktlen, 0);
if (slen != 0) {
d->bd_fcount++;
#ifdef MAC
if (mac_check_bpfdesc_receive(d, bp->bif_ifp) == 0)
#endif
catchpacket(d, (u_char *)m, pktlen, slen,
bpf_mcopy);
}
BPFD_UNLOCK(d);
}
BPFIF_UNLOCK(bp);
}
/*
* Incoming linkage from device drivers, when packet is in
* an mbuf chain and to be prepended by a contiguous header.
*/
void
bpf_mtap2(bp, data, dlen, m)
struct bpf_if *bp;
void *data;
u_int dlen;
struct mbuf *m;
{
struct mbuf mb;
struct bpf_d *d;
u_int pktlen, slen;
/*
* Lockless read to avoid cost of locking the interface if there are
* no descriptors attached.
*/
if (LIST_EMPTY(&bp->bif_dlist))
return;
pktlen = m_length(m, NULL);
/*
* Craft on-stack mbuf suitable for passing to bpf_filter.
* Note that we cut corners here; we only setup what's
* absolutely needed--this mbuf should never go anywhere else.
*/
mb.m_next = m;
mb.m_data = data;
mb.m_len = dlen;
pktlen += dlen;
BPFIF_LOCK(bp);
LIST_FOREACH(d, &bp->bif_dlist, bd_next) {
if (!d->bd_seesent && (m->m_pkthdr.rcvif == NULL))
continue;
BPFD_LOCK(d);
++d->bd_rcount;
slen = bpf_filter(d->bd_rfilter, (u_char *)&mb, pktlen, 0);
if (slen != 0) {
d->bd_fcount++;
#ifdef MAC
if (mac_check_bpfdesc_receive(d, bp->bif_ifp) == 0)
#endif
catchpacket(d, (u_char *)&mb, pktlen, slen,
bpf_mcopy);
}
BPFD_UNLOCK(d);
}
BPFIF_UNLOCK(bp);
}
/*
* Move the packet data from interface memory (pkt) into the
* store buffer. "cpfn" is the routine called to do the actual data
* transfer. bcopy is passed in to copy contiguous chunks, while
* bpf_mcopy is passed in to copy mbuf chains. In the latter case,
* pkt is really an mbuf.
*/
static void
catchpacket(d, pkt, pktlen, snaplen, cpfn)
struct bpf_d *d;
u_char *pkt;
u_int pktlen, snaplen;
void (*cpfn)(const void *, void *, size_t);
{
struct bpf_hdr *hp;
int totlen, curlen;
int hdrlen = d->bd_bif->bif_hdrlen;
int do_wakeup = 0;
BPFD_LOCK_ASSERT(d);
/*
* Figure out how many bytes to move. If the packet is
* greater or equal to the snapshot length, transfer that
* much. Otherwise, transfer the whole packet (unless
* we hit the buffer size limit).
*/
totlen = hdrlen + min(snaplen, pktlen);
if (totlen > d->bd_bufsize)
totlen = d->bd_bufsize;
/*
* Round up the end of the previous packet to the next longword.
*/
curlen = BPF_WORDALIGN(d->bd_slen);
if (curlen + totlen > d->bd_bufsize) {
/*
* This packet will overflow the storage buffer.
* Rotate the buffers if we can, then wakeup any
* pending reads.
*/
if (d->bd_fbuf == NULL) {
/*
* We haven't completed the previous read yet,
* so drop the packet.
*/
++d->bd_dcount;
return;
}
ROTATE_BUFFERS(d);
do_wakeup = 1;
curlen = 0;
}
else if (d->bd_immediate || d->bd_state == BPF_TIMED_OUT)
/*
* Immediate mode is set, or the read timeout has
* already expired during a select call. A packet
* arrived, so the reader should be woken up.
*/
do_wakeup = 1;
/*
* Append the bpf header.
*/
hp = (struct bpf_hdr *)(d->bd_sbuf + curlen);
microtime(&hp->bh_tstamp);
hp->bh_datalen = pktlen;
hp->bh_hdrlen = hdrlen;
/*
* Copy the packet data into the store buffer and update its length.
*/
(*cpfn)(pkt, (u_char *)hp + hdrlen, (hp->bh_caplen = totlen - hdrlen));
d->bd_slen = curlen + totlen;
if (do_wakeup)
bpf_wakeup(d);
}
/*
* Initialize all nonzero fields of a descriptor.
*/
static int
bpf_allocbufs(d)
struct bpf_d *d;
{
d->bd_fbuf = (caddr_t)malloc(d->bd_bufsize, M_BPF, M_WAITOK);
if (d->bd_fbuf == NULL)
return (ENOBUFS);
d->bd_sbuf = (caddr_t)malloc(d->bd_bufsize, M_BPF, M_WAITOK);
if (d->bd_sbuf == NULL) {
free(d->bd_fbuf, M_BPF);
return (ENOBUFS);
}
d->bd_slen = 0;
d->bd_hlen = 0;
return (0);
}
/*
* Free buffers currently in use by a descriptor.
* Called on close.
*/
static void
bpf_freed(d)
struct bpf_d *d;
{
/*
* We don't need to lock out interrupts since this descriptor has
* been detached from its interface and it yet hasn't been marked
* free.
*/
if (d->bd_sbuf != NULL) {
free(d->bd_sbuf, M_BPF);
if (d->bd_hbuf != NULL)
free(d->bd_hbuf, M_BPF);
if (d->bd_fbuf != NULL)
free(d->bd_fbuf, M_BPF);
}
if (d->bd_rfilter)
free((caddr_t)d->bd_rfilter, M_BPF);
if (d->bd_wfilter)
free((caddr_t)d->bd_wfilter, M_BPF);
mtx_destroy(&d->bd_mtx);
}
/*
* Attach an interface to bpf. dlt is the link layer type; hdrlen is the
* fixed size of the link header (variable length headers not yet supported).
*/
void
bpfattach(ifp, dlt, hdrlen)
struct ifnet *ifp;
u_int dlt, hdrlen;
{
bpfattach2(ifp, dlt, hdrlen, &ifp->if_bpf);
}
/*
* Attach an interface to bpf. ifp is a pointer to the structure
* defining the interface to be attached, dlt is the link layer type,
* and hdrlen is the fixed size of the link header (variable length
* headers are not yet supporrted).
*/
void
bpfattach2(ifp, dlt, hdrlen, driverp)
struct ifnet *ifp;
u_int dlt, hdrlen;
struct bpf_if **driverp;
{
struct bpf_if *bp;
bp = (struct bpf_if *)malloc(sizeof(*bp), M_BPF, M_NOWAIT | M_ZERO);
if (bp == NULL)
panic("bpfattach");
LIST_INIT(&bp->bif_dlist);
bp->bif_driverp = driverp;
bp->bif_ifp = ifp;
bp->bif_dlt = dlt;
mtx_init(&bp->bif_mtx, "bpf interface lock", NULL, MTX_DEF);
mtx_lock(&bpf_mtx);
LIST_INSERT_HEAD(&bpf_iflist, bp, bif_next);
mtx_unlock(&bpf_mtx);
*bp->bif_driverp = NULL;
/*
* Compute the length of the bpf header. This is not necessarily
* equal to SIZEOF_BPF_HDR because we want to insert spacing such
* that the network layer header begins on a longword boundary (for
* performance reasons and to alleviate alignment restrictions).
*/
bp->bif_hdrlen = BPF_WORDALIGN(hdrlen + SIZEOF_BPF_HDR) - hdrlen;
if (bootverbose)
if_printf(ifp, "bpf attached\n");
}
/*
* Detach bpf from an interface. This involves detaching each descriptor
* associated with the interface, and leaving bd_bif NULL. Notify each
* descriptor as it's detached so that any sleepers wake up and get
* ENXIO.
*/
void
bpfdetach(ifp)
struct ifnet *ifp;
{
struct bpf_if *bp;
struct bpf_d *d;
/* Locate BPF interface information */
mtx_lock(&bpf_mtx);
LIST_FOREACH(bp, &bpf_iflist, bif_next) {
if (ifp == bp->bif_ifp)
break;
}
/* Interface wasn't attached */
if ((bp == NULL) || (bp->bif_ifp == NULL)) {
mtx_unlock(&bpf_mtx);
printf("bpfdetach: %s was not attached\n", ifp->if_xname);
return;
}
LIST_REMOVE(bp, bif_next);
mtx_unlock(&bpf_mtx);
while ((d = LIST_FIRST(&bp->bif_dlist)) != NULL) {
bpf_detachd(d);
BPFD_LOCK(d);
bpf_wakeup(d);
BPFD_UNLOCK(d);
}
mtx_destroy(&bp->bif_mtx);
free(bp, M_BPF);
}
/*
* Get a list of available data link type of the interface.
*/
static int
bpf_getdltlist(d, bfl)
struct bpf_d *d;
struct bpf_dltlist *bfl;
{
int n, error;
struct ifnet *ifp;
struct bpf_if *bp;
ifp = d->bd_bif->bif_ifp;
n = 0;
error = 0;
mtx_lock(&bpf_mtx);
LIST_FOREACH(bp, &bpf_iflist, bif_next) {
if (bp->bif_ifp != ifp)
continue;
if (bfl->bfl_list != NULL) {
if (n >= bfl->bfl_len) {
mtx_unlock(&bpf_mtx);
return (ENOMEM);
}
error = copyout(&bp->bif_dlt,
bfl->bfl_list + n, sizeof(u_int));
}
n++;
}
mtx_unlock(&bpf_mtx);
bfl->bfl_len = n;
return (error);
}
/*
* Set the data link type of a BPF instance.
*/
static int
bpf_setdlt(d, dlt)
struct bpf_d *d;
u_int dlt;
{
int error, opromisc;
struct ifnet *ifp;
struct bpf_if *bp;
if (d->bd_bif->bif_dlt == dlt)
return (0);
ifp = d->bd_bif->bif_ifp;
mtx_lock(&bpf_mtx);
LIST_FOREACH(bp, &bpf_iflist, bif_next) {
if (bp->bif_ifp == ifp && bp->bif_dlt == dlt)
break;
}
mtx_unlock(&bpf_mtx);
if (bp != NULL) {
opromisc = d->bd_promisc;
bpf_detachd(d);
bpf_attachd(d, bp);
BPFD_LOCK(d);
reset_d(d);
BPFD_UNLOCK(d);
if (opromisc) {
error = ifpromisc(bp->bif_ifp, 1);
if (error)
if_printf(bp->bif_ifp,
"bpf_setdlt: ifpromisc failed (%d)\n",
error);
else
d->bd_promisc = 1;
}
}
return (bp == NULL ? EINVAL : 0);
}
static void
bpf_clone(arg, cred, name, namelen, dev)
void *arg;
struct ucred *cred;
char *name;
int namelen;
struct cdev **dev;
{
int u;
if (*dev != NULL)
return;
if (dev_stdclone(name, NULL, "bpf", &u) != 1)
return;
*dev = make_dev(&bpf_cdevsw, unit2minor(u), UID_ROOT, GID_WHEEL, 0600,
"bpf%d", u);
dev_ref(*dev);
(*dev)->si_flags |= SI_CHEAPCLONE;
return;
}
static void
bpf_drvinit(unused)
void *unused;
{
mtx_init(&bpf_mtx, "bpf global lock", NULL, MTX_DEF);
LIST_INIT(&bpf_iflist);
EVENTHANDLER_REGISTER(dev_clone, bpf_clone, 0, 1000);
}
static void
bpfstats_fill_xbpf(struct xbpf_d *d, struct bpf_d *bd)
{
bzero(d, sizeof(*d));
BPFD_LOCK_ASSERT(bd);
d->bd_immediate = bd->bd_immediate;
d->bd_promisc = bd->bd_promisc;
d->bd_hdrcmplt = bd->bd_hdrcmplt;
d->bd_seesent = bd->bd_seesent;
d->bd_async = bd->bd_async;
d->bd_rcount = bd->bd_rcount;
d->bd_dcount = bd->bd_dcount;
d->bd_fcount = bd->bd_fcount;
d->bd_sig = bd->bd_sig;
d->bd_slen = bd->bd_slen;
d->bd_hlen = bd->bd_hlen;
d->bd_bufsize = bd->bd_bufsize;
d->bd_pid = bd->bd_pid;
strlcpy(d->bd_ifname,
bd->bd_bif->bif_ifp->if_xname, IFNAMSIZ);
strlcpy(d->bd_pcomm, bd->bd_pcomm, MAXCOMLEN);
d->bd_locked = bd->bd_locked;
}
static int
bpf_stats_sysctl(SYSCTL_HANDLER_ARGS)
{
struct xbpf_d *xbdbuf, *xbd;
int index, error;
struct bpf_if *bp;
struct bpf_d *bd;
/*
* XXX This is not technically correct. It is possible for non
* privileged users to open bpf devices. It would make sense
* if the users who opened the devices were able to retrieve
* the statistics for them, too.
*/
error = suser(req->td);
if (error)
return (error);
if (req->oldptr == NULL)
return (SYSCTL_OUT(req, 0, bpf_bpfd_cnt * sizeof(*xbd)));
if (bpf_bpfd_cnt == 0)
return (SYSCTL_OUT(req, 0, 0));
xbdbuf = malloc(req->oldlen, M_BPF, M_WAITOK);
mtx_lock(&bpf_mtx);
if (req->oldlen < (bpf_bpfd_cnt * sizeof(*xbd))) {
mtx_unlock(&bpf_mtx);
free(xbdbuf, M_BPF);
return (ENOMEM);
}
index = 0;
LIST_FOREACH(bp, &bpf_iflist, bif_next) {
LIST_FOREACH(bd, &bp->bif_dlist, bd_next) {
xbd = &xbdbuf[index++];
BPFD_LOCK(bd);
bpfstats_fill_xbpf(xbd, bd);
BPFD_UNLOCK(bd);
}
}
mtx_unlock(&bpf_mtx);
error = SYSCTL_OUT(req, xbdbuf, index * sizeof(*xbd));
free(xbdbuf, M_BPF);
return (error);
}
SYSINIT(bpfdev,SI_SUB_DRIVERS,SI_ORDER_MIDDLE,bpf_drvinit,NULL)
#else /* !DEV_BPF && !NETGRAPH_BPF */
/*
* NOP stubs to allow bpf-using drivers to load and function.
*
* A 'better' implementation would allow the core bpf functionality
* to be loaded at runtime.
*/
void
bpf_tap(bp, pkt, pktlen)
struct bpf_if *bp;
u_char *pkt;
u_int pktlen;
{
}
void
bpf_mtap(bp, m)
struct bpf_if *bp;
struct mbuf *m;
{
}
void
bpf_mtap2(bp, d, l, m)
struct bpf_if *bp;
void *d;
u_int l;
struct mbuf *m;
{
}
void
bpfattach(ifp, dlt, hdrlen)
struct ifnet *ifp;
u_int dlt, hdrlen;
{
}
void
bpfattach2(ifp, dlt, hdrlen, driverp)
struct ifnet *ifp;
u_int dlt, hdrlen;
struct bpf_if **driverp;
{
}
void
bpfdetach(ifp)
struct ifnet *ifp;
{
}
u_int
bpf_filter(pc, p, wirelen, buflen)
const struct bpf_insn *pc;
u_char *p;
u_int wirelen;
u_int buflen;
{
return -1; /* "no filter" behaviour */
}
int
bpf_validate(f, len)
const struct bpf_insn *f;
int len;
{
return 0; /* false */
}
#endif /* !DEV_BPF && !NETGRAPH_BPF */
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