1311 lines
28 KiB
C
1311 lines
28 KiB
C
/*
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* Copyright (c) 1990, 1991, 1993
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* The Regents of the University of California. All rights reserved.
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*
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* This code is derived from the Stanford/CMU enet packet filter,
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* (net/enet.c) distributed as part of 4.3BSD, and code contributed
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* to Berkeley by Steven McCanne and Van Jacobson both of Lawrence
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* Berkeley Laboratory.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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* 3. All advertising materials mentioning features or use of this software
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* must display the following acknowledgement:
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* This product includes software developed by the University of
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* California, Berkeley and its contributors.
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* 4. Neither the name of the University nor the names of its contributors
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* may be used to endorse or promote products derived from this software
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* without specific prior written permission.
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*
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* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
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* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
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* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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* SUCH DAMAGE.
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*
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* @(#)bpf.c 8.2 (Berkeley) 3/28/94
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*
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* $Id: bpf.c,v 1.3 1994/08/20 03:48:55 davidg Exp $
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*/
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#include "bpfilter.h"
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#if NBPFILTER > 0
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#ifndef __GNUC__
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#define inline
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#else
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#define inline __inline
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#endif
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#include <sys/param.h>
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#include <sys/systm.h>
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#include <sys/mbuf.h>
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#include <sys/buf.h>
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#include <sys/time.h>
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#include <sys/proc.h>
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#include <sys/user.h>
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#include <sys/ioctl.h>
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#include <sys/file.h>
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#if defined(sparc) && BSD < 199103
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#include <sys/stream.h>
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#endif
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#include <sys/tty.h>
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#include <sys/uio.h>
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#include <sys/protosw.h>
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#include <sys/socket.h>
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#include <net/if.h>
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#include <net/bpf.h>
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#include <net/bpfdesc.h>
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#include <sys/errno.h>
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#include <netinet/in.h>
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#include <netinet/if_ether.h>
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#include <sys/kernel.h>
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/*
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* Older BSDs don't have kernel malloc.
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*/
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#if BSD < 199103
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extern bcopy();
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static caddr_t bpf_alloc();
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#include <net/bpf_compat.h>
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#define BPF_BUFSIZE (MCLBYTES-8)
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#define UIOMOVE(cp, len, code, uio) uiomove(cp, len, code, uio)
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#else
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#define BPF_BUFSIZE 4096
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#define UIOMOVE(cp, len, code, uio) uiomove(cp, len, uio)
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#endif
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#define PRINET 26 /* interruptible */
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/*
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* The default read buffer size is patchable.
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*/
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int bpf_bufsize = BPF_BUFSIZE;
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/*
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* bpf_iflist is the list of interfaces; each corresponds to an ifnet
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* bpf_dtab holds the descriptors, indexed by minor device #
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*/
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struct bpf_if *bpf_iflist;
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struct bpf_d bpf_dtab[NBPFILTER];
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#if BSD >= 199207
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/*
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* bpfilterattach() is called at boot time in new systems. We do
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* nothing here since old systems will not call this.
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*/
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/* ARGSUSED */
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void
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bpfilterattach(n)
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int n;
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{
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}
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#endif
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static int bpf_allocbufs __P((struct bpf_d *));
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static void bpf_freed __P((struct bpf_d *));
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static void bpf_ifname __P((struct ifnet *, struct ifreq *));
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static void bpf_mcopy __P((const void *, void *, u_int));
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static int bpf_movein __P((struct uio *, int,
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struct mbuf **, struct sockaddr *, int *));
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static int bpf_setif __P((struct bpf_d *, struct ifreq *));
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static inline void
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bpf_wakeup __P((struct bpf_d *));
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static void catchpacket __P((struct bpf_d *, u_char *, u_int,
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u_int, void (*)(const void *, void *, u_int)));
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static void reset_d __P((struct bpf_d *));
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static int
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bpf_movein(uio, linktype, mp, sockp, datlen)
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register struct uio *uio;
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int linktype, *datlen;
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register struct mbuf **mp;
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register struct sockaddr *sockp;
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{
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struct mbuf *m;
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int error;
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int len;
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int hlen;
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/*
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* Build a sockaddr based on the data link layer type.
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* We do this at this level because the ethernet header
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* is copied directly into the data field of the sockaddr.
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* In the case of SLIP, there is no header and the packet
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* is forwarded as is.
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* Also, we are careful to leave room at the front of the mbuf
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* for the link level header.
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*/
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switch (linktype) {
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case DLT_SLIP:
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sockp->sa_family = AF_INET;
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hlen = 0;
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break;
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case DLT_EN10MB:
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sockp->sa_family = AF_UNSPEC;
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/* XXX Would MAXLINKHDR be better? */
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hlen = sizeof(struct ether_header);
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break;
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case DLT_FDDI:
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sockp->sa_family = AF_UNSPEC;
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/* XXX 4(FORMAC)+6(dst)+6(src)+3(LLC)+5(SNAP) */
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hlen = 24;
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break;
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case DLT_NULL:
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sockp->sa_family = AF_UNSPEC;
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hlen = 0;
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break;
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default:
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return (EIO);
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}
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len = uio->uio_resid;
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*datlen = len - hlen;
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if ((unsigned)len > MCLBYTES)
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return (EIO);
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MGET(m, M_WAIT, MT_DATA);
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if (m == 0)
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return (ENOBUFS);
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if (len > MLEN) {
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#if BSD >= 199103
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MCLGET(m, M_WAIT);
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if ((m->m_flags & M_EXT) == 0) {
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#else
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MCLGET(m);
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if (m->m_len != MCLBYTES) {
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#endif
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error = ENOBUFS;
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goto bad;
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}
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}
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m->m_len = len;
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*mp = m;
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/*
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* Make room for link header.
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*/
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if (hlen != 0) {
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m->m_len -= hlen;
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#if BSD >= 199103
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m->m_data += hlen; /* XXX */
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#else
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m->m_off += hlen;
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#endif
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error = UIOMOVE((caddr_t)sockp->sa_data, hlen, UIO_WRITE, uio);
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if (error)
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goto bad;
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}
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error = UIOMOVE(mtod(m, caddr_t), len - hlen, UIO_WRITE, uio);
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if (!error)
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return (0);
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bad:
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m_freem(m);
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return (error);
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}
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/*
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* Attach file to the bpf interface, i.e. make d listen on bp.
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* Must be called at splimp.
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*/
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static void
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bpf_attachd(d, bp)
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struct bpf_d *d;
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struct bpf_if *bp;
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{
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/*
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* Point d at bp, and add d to the interface's list of listeners.
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* Finally, point the driver's bpf cookie at the interface so
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* it will divert packets to bpf.
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*/
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d->bd_bif = bp;
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d->bd_next = bp->bif_dlist;
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bp->bif_dlist = d;
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*bp->bif_driverp = bp;
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}
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/*
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* Detach a file from its interface.
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*/
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static void
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bpf_detachd(d)
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struct bpf_d *d;
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{
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struct bpf_d **p;
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struct bpf_if *bp;
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bp = d->bd_bif;
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/*
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* Check if this descriptor had requested promiscuous mode.
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* If so, turn it off.
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*/
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if (d->bd_promisc) {
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d->bd_promisc = 0;
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if (ifpromisc(bp->bif_ifp, 0))
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/*
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* Something is really wrong if we were able to put
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* the driver into promiscuous mode, but can't
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* take it out.
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*/
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panic("bpf: ifpromisc failed");
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}
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/* Remove d from the interface's descriptor list. */
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p = &bp->bif_dlist;
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while (*p != d) {
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p = &(*p)->bd_next;
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if (*p == 0)
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panic("bpf_detachd: descriptor not in list");
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}
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*p = (*p)->bd_next;
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if (bp->bif_dlist == 0)
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/*
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* Let the driver know that there are no more listeners.
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*/
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*d->bd_bif->bif_driverp = 0;
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d->bd_bif = 0;
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}
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/*
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* Mark a descriptor free by making it point to itself.
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* This is probably cheaper than marking with a constant since
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* the address should be in a register anyway.
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*/
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#define D_ISFREE(d) ((d) == (d)->bd_next)
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#define D_MARKFREE(d) ((d)->bd_next = (d))
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#define D_MARKUSED(d) ((d)->bd_next = 0)
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/*
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* Open ethernet device. Returns ENXIO for illegal minor device number,
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* EBUSY if file is open by another process.
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*/
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/* ARGSUSED */
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int
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bpfopen(dev, flag)
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dev_t dev;
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int flag;
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{
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register struct bpf_d *d;
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if (minor(dev) >= NBPFILTER)
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return (ENXIO);
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/*
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* Each minor can be opened by only one process. If the requested
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* minor is in use, return EBUSY.
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*/
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d = &bpf_dtab[minor(dev)];
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if (!D_ISFREE(d))
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return (EBUSY);
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/* Mark "free" and do most initialization. */
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bzero((char *)d, sizeof(*d));
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d->bd_bufsize = bpf_bufsize;
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return (0);
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}
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/*
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* Close the descriptor by detaching it from its interface,
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* deallocating its buffers, and marking it free.
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*/
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/* ARGSUSED */
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int
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bpfclose(dev, flag)
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dev_t dev;
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int flag;
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{
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register struct bpf_d *d = &bpf_dtab[minor(dev)];
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register int s;
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s = splimp();
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if (d->bd_bif)
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bpf_detachd(d);
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splx(s);
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bpf_freed(d);
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return (0);
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}
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/*
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* Support for SunOS, which does not have tsleep.
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*/
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#if BSD < 199103
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static
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bpf_timeout(arg)
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caddr_t arg;
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{
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struct bpf_d *d = (struct bpf_d *)arg;
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d->bd_timedout = 1;
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wakeup(arg);
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}
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#define BPF_SLEEP(chan, pri, s, t) bpf_sleep((struct bpf_d *)chan)
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int
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bpf_sleep(d)
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register struct bpf_d *d;
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{
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register int rto = d->bd_rtout;
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register int st;
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if (rto != 0) {
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d->bd_timedout = 0;
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timeout(bpf_timeout, (caddr_t)d, rto);
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}
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st = sleep((caddr_t)d, PRINET|PCATCH);
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if (rto != 0) {
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if (d->bd_timedout == 0)
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untimeout(bpf_timeout, (caddr_t)d);
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else if (st == 0)
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return EWOULDBLOCK;
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}
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return (st != 0) ? EINTR : 0;
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}
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#else
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#define BPF_SLEEP tsleep
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#endif
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/*
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* Rotate the packet buffers in descriptor d. Move the store buffer
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* into the hold slot, and the free buffer into the store slot.
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* Zero the length of the new store buffer.
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*/
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#define ROTATE_BUFFERS(d) \
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(d)->bd_hbuf = (d)->bd_sbuf; \
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(d)->bd_hlen = (d)->bd_slen; \
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(d)->bd_sbuf = (d)->bd_fbuf; \
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(d)->bd_slen = 0; \
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(d)->bd_fbuf = 0;
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/*
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* bpfread - read next chunk of packets from buffers
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*/
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int
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bpfread(dev, uio)
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dev_t dev;
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register struct uio *uio;
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{
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register struct bpf_d *d = &bpf_dtab[minor(dev)];
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int error;
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int s;
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/*
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* Restrict application to use a buffer the same size as
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* as kernel buffers.
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*/
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if (uio->uio_resid != d->bd_bufsize)
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return (EINVAL);
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s = splimp();
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/*
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* If the hold buffer is empty, then do a timed sleep, which
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* ends when the timeout expires or when enough packets
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* have arrived to fill the store buffer.
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*/
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while (d->bd_hbuf == 0) {
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if (d->bd_immediate && d->bd_slen != 0) {
|
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/*
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* A packet(s) either arrived since the previous
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* read or arrived while we were asleep.
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* Rotate the buffers and return what's here.
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*/
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ROTATE_BUFFERS(d);
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break;
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}
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error = BPF_SLEEP((caddr_t)d, PRINET|PCATCH, "bpf",
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d->bd_rtout);
|
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if (error == EINTR || error == ERESTART) {
|
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splx(s);
|
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return (error);
|
|
}
|
|
if (error == EWOULDBLOCK) {
|
|
/*
|
|
* On a timeout, return what's in the buffer,
|
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* which may be nothing. If there is something
|
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* in the store buffer, we can rotate the buffers.
|
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*/
|
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if (d->bd_hbuf)
|
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/*
|
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* We filled up the buffer in between
|
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* getting the timeout and arriving
|
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* here, so we don't need to rotate.
|
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*/
|
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break;
|
|
|
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if (d->bd_slen == 0) {
|
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splx(s);
|
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return (0);
|
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}
|
|
ROTATE_BUFFERS(d);
|
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break;
|
|
}
|
|
}
|
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/*
|
|
* At this point, we know we have something in the hold slot.
|
|
*/
|
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splx(s);
|
|
|
|
/*
|
|
* Move data from hold buffer into user space.
|
|
* We know the entire buffer is transferred since
|
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* we checked above that the read buffer is bpf_bufsize bytes.
|
|
*/
|
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error = UIOMOVE(d->bd_hbuf, d->bd_hlen, UIO_READ, uio);
|
|
|
|
s = splimp();
|
|
d->bd_fbuf = d->bd_hbuf;
|
|
d->bd_hbuf = 0;
|
|
d->bd_hlen = 0;
|
|
splx(s);
|
|
|
|
return (error);
|
|
}
|
|
|
|
|
|
/*
|
|
* If there are processes sleeping on this descriptor, wake them up.
|
|
*/
|
|
static inline void
|
|
bpf_wakeup(d)
|
|
register struct bpf_d *d;
|
|
{
|
|
wakeup((caddr_t)d);
|
|
#if BSD >= 199103
|
|
selwakeup(&d->bd_sel);
|
|
/* XXX */
|
|
d->bd_sel.si_pid = 0;
|
|
#else
|
|
if (d->bd_selproc) {
|
|
selwakeup(d->bd_selproc, (int)d->bd_selcoll);
|
|
d->bd_selcoll = 0;
|
|
d->bd_selproc = 0;
|
|
}
|
|
#endif
|
|
}
|
|
|
|
int
|
|
bpfwrite(dev, uio)
|
|
dev_t dev;
|
|
struct uio *uio;
|
|
{
|
|
register struct bpf_d *d = &bpf_dtab[minor(dev)];
|
|
struct ifnet *ifp;
|
|
struct mbuf *m;
|
|
int error, s;
|
|
static struct sockaddr dst;
|
|
int datlen;
|
|
|
|
if (d->bd_bif == 0)
|
|
return (ENXIO);
|
|
|
|
ifp = d->bd_bif->bif_ifp;
|
|
|
|
if (uio->uio_resid == 0)
|
|
return (0);
|
|
|
|
error = bpf_movein(uio, (int)d->bd_bif->bif_dlt, &m, &dst, &datlen);
|
|
if (error)
|
|
return (error);
|
|
|
|
if (datlen > ifp->if_mtu)
|
|
return (EMSGSIZE);
|
|
|
|
s = splnet();
|
|
#if BSD >= 199103
|
|
error = (*ifp->if_output)(ifp, m, &dst, (struct rtentry *)0);
|
|
#else
|
|
error = (*ifp->if_output)(ifp, m, &dst);
|
|
#endif
|
|
splx(s);
|
|
/*
|
|
* The driver frees the mbuf.
|
|
*/
|
|
return (error);
|
|
}
|
|
|
|
/*
|
|
* Reset a descriptor by flushing its packet buffer and clearing the
|
|
* receive and drop counts. Should be called at splimp.
|
|
*/
|
|
static void
|
|
reset_d(d)
|
|
struct bpf_d *d;
|
|
{
|
|
if (d->bd_hbuf) {
|
|
/* Free the hold buffer. */
|
|
d->bd_fbuf = d->bd_hbuf;
|
|
d->bd_hbuf = 0;
|
|
}
|
|
d->bd_slen = 0;
|
|
d->bd_hlen = 0;
|
|
d->bd_rcount = 0;
|
|
d->bd_dcount = 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.
|
|
* 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.
|
|
*/
|
|
/* ARGSUSED */
|
|
int
|
|
bpfioctl(dev, cmd, addr, flag)
|
|
dev_t dev;
|
|
int cmd;
|
|
caddr_t addr;
|
|
int flag;
|
|
{
|
|
register struct bpf_d *d = &bpf_dtab[minor(dev)];
|
|
int s, error = 0;
|
|
|
|
switch (cmd) {
|
|
|
|
default:
|
|
error = EINVAL;
|
|
break;
|
|
|
|
/*
|
|
* Check for read packet available.
|
|
*/
|
|
case FIONREAD:
|
|
{
|
|
int n;
|
|
|
|
s = splimp();
|
|
n = d->bd_slen;
|
|
if (d->bd_hbuf)
|
|
n += d->bd_hlen;
|
|
splx(s);
|
|
|
|
*(int *)addr = n;
|
|
break;
|
|
}
|
|
|
|
case SIOCGIFADDR:
|
|
{
|
|
struct ifnet *ifp;
|
|
|
|
if (d->bd_bif == 0)
|
|
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 BSD < 199103
|
|
error = EINVAL;
|
|
#else
|
|
if (d->bd_bif != 0)
|
|
error = EINVAL;
|
|
else {
|
|
register 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;
|
|
}
|
|
#endif
|
|
break;
|
|
|
|
/*
|
|
* Set link layer read filter.
|
|
*/
|
|
case BIOCSETF:
|
|
error = bpf_setf(d, (struct bpf_program *)addr);
|
|
break;
|
|
|
|
/*
|
|
* Flush read packet buffer.
|
|
*/
|
|
case BIOCFLUSH:
|
|
s = splimp();
|
|
reset_d(d);
|
|
splx(s);
|
|
break;
|
|
|
|
/*
|
|
* Put interface into promiscuous mode.
|
|
*/
|
|
case BIOCPROMISC:
|
|
if (d->bd_bif == 0) {
|
|
/*
|
|
* No interface attached yet.
|
|
*/
|
|
error = EINVAL;
|
|
break;
|
|
}
|
|
s = splimp();
|
|
if (d->bd_promisc == 0) {
|
|
error = ifpromisc(d->bd_bif->bif_ifp, 1);
|
|
if (error == 0)
|
|
d->bd_promisc = 1;
|
|
}
|
|
splx(s);
|
|
break;
|
|
|
|
/*
|
|
* Get device parameters.
|
|
*/
|
|
case BIOCGDLT:
|
|
if (d->bd_bif == 0)
|
|
error = EINVAL;
|
|
else
|
|
*(u_int *)addr = d->bd_bif->bif_dlt;
|
|
break;
|
|
|
|
/*
|
|
* Set interface name.
|
|
*/
|
|
case BIOCGETIF:
|
|
if (d->bd_bif == 0)
|
|
error = EINVAL;
|
|
else
|
|
bpf_ifname(d->bd_bif->bif_ifp, (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;
|
|
u_long msec;
|
|
|
|
/* Compute number of milliseconds. */
|
|
msec = tv->tv_sec * 1000 + tv->tv_usec / 1000;
|
|
/* Scale milliseconds to ticks. Assume hard
|
|
clock has millisecond or greater resolution
|
|
(i.e. tick >= 1000). For 10ms hardclock,
|
|
tick/1000 = 10, so rtout<-msec/10. */
|
|
d->bd_rtout = msec / (tick / 1000);
|
|
break;
|
|
}
|
|
|
|
/*
|
|
* Get read timeout.
|
|
*/
|
|
case BIOCGRTIMEOUT:
|
|
{
|
|
struct timeval *tv = (struct timeval *)addr;
|
|
u_long msec = d->bd_rtout;
|
|
|
|
msec *= tick / 1000;
|
|
tv->tv_sec = msec / 1000;
|
|
tv->tv_usec = msec % 1000;
|
|
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;
|
|
}
|
|
}
|
|
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.
|
|
*/
|
|
int
|
|
bpf_setf(d, fp)
|
|
struct bpf_d *d;
|
|
struct bpf_program *fp;
|
|
{
|
|
struct bpf_insn *fcode, *old;
|
|
u_int flen, size;
|
|
int s;
|
|
|
|
old = d->bd_filter;
|
|
if (fp->bf_insns == 0) {
|
|
if (fp->bf_len != 0)
|
|
return (EINVAL);
|
|
s = splimp();
|
|
d->bd_filter = 0;
|
|
reset_d(d);
|
|
splx(s);
|
|
if (old != 0)
|
|
free((caddr_t)old, M_DEVBUF);
|
|
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_DEVBUF, M_WAITOK);
|
|
if (copyin((caddr_t)fp->bf_insns, (caddr_t)fcode, size) == 0 &&
|
|
bpf_validate(fcode, (int)flen)) {
|
|
s = splimp();
|
|
d->bd_filter = fcode;
|
|
reset_d(d);
|
|
splx(s);
|
|
if (old != 0)
|
|
free((caddr_t)old, M_DEVBUF);
|
|
|
|
return (0);
|
|
}
|
|
free((caddr_t)fcode, M_DEVBUF);
|
|
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;
|
|
char *cp;
|
|
int unit, s, error;
|
|
|
|
/*
|
|
* Separate string into name part and unit number. Put a null
|
|
* byte at the end of the name part, and compute the number.
|
|
* If the a unit number is unspecified, the default is 0,
|
|
* as initialized above. XXX This should be common code.
|
|
*/
|
|
unit = 0;
|
|
cp = ifr->ifr_name;
|
|
cp[sizeof(ifr->ifr_name) - 1] = '\0';
|
|
while (*cp++) {
|
|
if (*cp >= '0' && *cp <= '9') {
|
|
unit = *cp - '0';
|
|
*cp++ = '\0';
|
|
while (*cp)
|
|
unit = 10 * unit + *cp++ - '0';
|
|
break;
|
|
}
|
|
}
|
|
/*
|
|
* Look through attached interfaces for the named one.
|
|
*/
|
|
for (bp = bpf_iflist; bp != 0; bp = bp->bif_next) {
|
|
struct ifnet *ifp = bp->bif_ifp;
|
|
|
|
if (ifp == 0 || unit != ifp->if_unit
|
|
|| strcmp(ifp->if_name, ifr->ifr_name) != 0)
|
|
continue;
|
|
/*
|
|
* We found the requested interface.
|
|
* If it's not up, return an error.
|
|
* Allocate the packet buffers if we need to.
|
|
* If we're already attached to requested interface,
|
|
* just flush the buffer.
|
|
*/
|
|
if ((ifp->if_flags & IFF_UP) == 0)
|
|
return (ENETDOWN);
|
|
|
|
if (d->bd_sbuf == 0) {
|
|
error = bpf_allocbufs(d);
|
|
if (error != 0)
|
|
return (error);
|
|
}
|
|
s = splimp();
|
|
if (bp != d->bd_bif) {
|
|
if (d->bd_bif)
|
|
/*
|
|
* Detach if attached to something else.
|
|
*/
|
|
bpf_detachd(d);
|
|
|
|
bpf_attachd(d, bp);
|
|
}
|
|
reset_d(d);
|
|
splx(s);
|
|
return (0);
|
|
}
|
|
/* Not found. */
|
|
return (ENXIO);
|
|
}
|
|
|
|
/*
|
|
* Convert an interface name plus unit number of an ifp to a single
|
|
* name which is returned in the ifr.
|
|
*/
|
|
static void
|
|
bpf_ifname(ifp, ifr)
|
|
struct ifnet *ifp;
|
|
struct ifreq *ifr;
|
|
{
|
|
char *s = ifp->if_name;
|
|
char *d = ifr->ifr_name;
|
|
|
|
while (*d++ = *s++)
|
|
continue;
|
|
/* XXX Assume that unit number is less than 10. */
|
|
*d++ = ifp->if_unit + '0';
|
|
*d = '\0';
|
|
}
|
|
|
|
/*
|
|
* The new select interface passes down the proc pointer; the old select
|
|
* stubs had to grab it out of the user struct. This glue allows either case.
|
|
*/
|
|
#if BSD >= 199103
|
|
#define bpf_select bpfselect
|
|
#else
|
|
int
|
|
bpfselect(dev, rw)
|
|
register dev_t dev;
|
|
int rw;
|
|
{
|
|
return (bpf_select(dev, rw, u.u_procp));
|
|
}
|
|
#endif
|
|
|
|
/*
|
|
* Support for select() system call
|
|
*
|
|
* Return true iff the specific operation will not block indefinitely.
|
|
* Otherwise, return false but make a note that a selwakeup() must be done.
|
|
*/
|
|
int
|
|
bpf_select(dev, rw, p)
|
|
register dev_t dev;
|
|
int rw;
|
|
struct proc *p;
|
|
{
|
|
register struct bpf_d *d;
|
|
register int s;
|
|
|
|
if (rw != FREAD)
|
|
return (0);
|
|
/*
|
|
* An imitation of the FIONREAD ioctl code.
|
|
*/
|
|
d = &bpf_dtab[minor(dev)];
|
|
|
|
s = splimp();
|
|
if (d->bd_hlen != 0 || (d->bd_immediate && d->bd_slen != 0)) {
|
|
/*
|
|
* There is data waiting.
|
|
*/
|
|
splx(s);
|
|
return (1);
|
|
}
|
|
#if BSD >= 199103
|
|
selrecord(p, &d->bd_sel);
|
|
#else
|
|
/*
|
|
* No data ready. If there's already a select() waiting on this
|
|
* minor device then this is a collision. This shouldn't happen
|
|
* because minors really should not be shared, but if a process
|
|
* forks while one of these is open, it is possible that both
|
|
* processes could select on the same descriptor.
|
|
*/
|
|
if (d->bd_selproc && d->bd_selproc->p_wchan == (caddr_t)&selwait)
|
|
d->bd_selcoll = 1;
|
|
else
|
|
d->bd_selproc = p;
|
|
#endif
|
|
splx(s);
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* 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(arg, pkt, pktlen)
|
|
caddr_t arg;
|
|
register u_char *pkt;
|
|
register u_int pktlen;
|
|
{
|
|
struct bpf_if *bp;
|
|
register struct bpf_d *d;
|
|
register u_int slen;
|
|
/*
|
|
* Note that the ipl does not have to be raised at this point.
|
|
* The only problem that could arise here is that if two different
|
|
* interfaces shared any data. This is not the case.
|
|
*/
|
|
bp = (struct bpf_if *)arg;
|
|
for (d = bp->bif_dlist; d != 0; d = d->bd_next) {
|
|
++d->bd_rcount;
|
|
slen = bpf_filter(d->bd_filter, pkt, pktlen, pktlen);
|
|
if (slen != 0)
|
|
catchpacket(d, pkt, pktlen, slen, bcopy);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* 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;
|
|
register u_int len;
|
|
{
|
|
register const struct mbuf *m;
|
|
register u_int count;
|
|
u_char *dst;
|
|
|
|
m = src_arg;
|
|
dst = dst_arg;
|
|
while (len > 0) {
|
|
if (m == 0)
|
|
panic("bpf_mcopy");
|
|
count = min(m->m_len, len);
|
|
bcopy(mtod(m, caddr_t), (caddr_t)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(arg, m)
|
|
caddr_t arg;
|
|
struct mbuf *m;
|
|
{
|
|
struct bpf_if *bp = (struct bpf_if *)arg;
|
|
struct bpf_d *d;
|
|
u_int pktlen, slen;
|
|
struct mbuf *m0;
|
|
|
|
pktlen = 0;
|
|
for (m0 = m; m0 != 0; m0 = m0->m_next)
|
|
pktlen += m0->m_len;
|
|
|
|
for (d = bp->bif_dlist; d != 0; d = d->bd_next) {
|
|
++d->bd_rcount;
|
|
slen = bpf_filter(d->bd_filter, (u_char *)m, pktlen, 0);
|
|
if (slen != 0)
|
|
catchpacket(d, (u_char *)m, pktlen, slen, bpf_mcopy);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Move the packet data from interface memory (pkt) into the
|
|
* store buffer. Return 1 if it's time to wakeup a listener (buffer full),
|
|
* otherwise 0. "copy" 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)
|
|
register struct bpf_d *d;
|
|
register u_char *pkt;
|
|
register u_int pktlen, snaplen;
|
|
register void (*cpfn)(const void *, void *, u_int);
|
|
{
|
|
register struct bpf_hdr *hp;
|
|
register int totlen, curlen;
|
|
register int hdrlen = d->bd_bif->bif_hdrlen;
|
|
/*
|
|
* 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 == 0) {
|
|
/*
|
|
* We haven't completed the previous read yet,
|
|
* so drop the packet.
|
|
*/
|
|
++d->bd_dcount;
|
|
return;
|
|
}
|
|
ROTATE_BUFFERS(d);
|
|
bpf_wakeup(d);
|
|
curlen = 0;
|
|
}
|
|
else if (d->bd_immediate)
|
|
/*
|
|
* Immediate mode is set. A packet arrived so any
|
|
* reads should be woken up.
|
|
*/
|
|
bpf_wakeup(d);
|
|
|
|
/*
|
|
* Append the bpf header.
|
|
*/
|
|
hp = (struct bpf_hdr *)(d->bd_sbuf + curlen);
|
|
#if BSD >= 199103
|
|
microtime(&hp->bh_tstamp);
|
|
#elif defined(sun)
|
|
uniqtime(&hp->bh_tstamp);
|
|
#else
|
|
hp->bh_tstamp = time;
|
|
#endif
|
|
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;
|
|
}
|
|
|
|
/*
|
|
* Initialize all nonzero fields of a descriptor.
|
|
*/
|
|
static int
|
|
bpf_allocbufs(d)
|
|
register struct bpf_d *d;
|
|
{
|
|
d->bd_fbuf = (caddr_t)malloc(d->bd_bufsize, M_DEVBUF, M_WAITOK);
|
|
if (d->bd_fbuf == 0)
|
|
return (ENOBUFS);
|
|
|
|
d->bd_sbuf = (caddr_t)malloc(d->bd_bufsize, M_DEVBUF, M_WAITOK);
|
|
if (d->bd_sbuf == 0) {
|
|
free(d->bd_fbuf, M_DEVBUF);
|
|
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)
|
|
register 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 != 0) {
|
|
free(d->bd_sbuf, M_DEVBUF);
|
|
if (d->bd_hbuf != 0)
|
|
free(d->bd_hbuf, M_DEVBUF);
|
|
if (d->bd_fbuf != 0)
|
|
free(d->bd_fbuf, M_DEVBUF);
|
|
}
|
|
if (d->bd_filter)
|
|
free((caddr_t)d->bd_filter, M_DEVBUF);
|
|
|
|
D_MARKFREE(d);
|
|
}
|
|
|
|
/*
|
|
* Attach an interface to bpf. driverp is a pointer to a (struct bpf_if *)
|
|
* in the driver's softc; dlt is the link layer type; hdrlen is the fixed
|
|
* size of the link header (variable length headers not yet supported).
|
|
*/
|
|
void
|
|
bpfattach(driverp, ifp, dlt, hdrlen)
|
|
caddr_t *driverp;
|
|
struct ifnet *ifp;
|
|
u_int dlt, hdrlen;
|
|
{
|
|
struct bpf_if *bp;
|
|
int i;
|
|
#if BSD < 199103
|
|
static struct bpf_if bpf_ifs[NBPFILTER];
|
|
static int bpfifno;
|
|
|
|
bp = (bpfifno < NBPFILTER) ? &bpf_ifs[bpfifno++] : 0;
|
|
#else
|
|
bp = (struct bpf_if *)malloc(sizeof(*bp), M_DEVBUF, M_DONTWAIT);
|
|
#endif
|
|
if (bp == 0)
|
|
panic("bpfattach");
|
|
|
|
bp->bif_dlist = 0;
|
|
bp->bif_driverp = (struct bpf_if **)driverp;
|
|
bp->bif_ifp = ifp;
|
|
bp->bif_dlt = dlt;
|
|
|
|
bp->bif_next = bpf_iflist;
|
|
bpf_iflist = bp;
|
|
|
|
*bp->bif_driverp = 0;
|
|
|
|
/*
|
|
* 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;
|
|
|
|
/*
|
|
* Mark all the descriptors free if this hasn't been done.
|
|
*/
|
|
if (!D_ISFREE(&bpf_dtab[0]))
|
|
for (i = 0; i < NBPFILTER; ++i)
|
|
D_MARKFREE(&bpf_dtab[i]);
|
|
|
|
printf("bpf: %s%d attached\n", ifp->if_name, ifp->if_unit);
|
|
}
|
|
|
|
#if BSD >= 199103
|
|
/* XXX This routine belongs in net/if.c. */
|
|
/*
|
|
* Set/clear promiscuous mode on interface ifp based on the truth value
|
|
* of pswitch. The calls are reference counted so that only the first
|
|
* "on" request actually has an effect, as does the final "off" request.
|
|
* Results are undefined if the "off" and "on" requests are not matched.
|
|
*/
|
|
int
|
|
ifpromisc(ifp, pswitch)
|
|
struct ifnet *ifp;
|
|
int pswitch;
|
|
{
|
|
struct ifreq ifr;
|
|
/*
|
|
* If the device is not configured up, we cannot put it in
|
|
* promiscuous mode.
|
|
*/
|
|
if ((ifp->if_flags & IFF_UP) == 0)
|
|
return (ENETDOWN);
|
|
|
|
if (pswitch) {
|
|
if (ifp->if_pcount++ != 0)
|
|
return (0);
|
|
ifp->if_flags |= IFF_PROMISC;
|
|
} else {
|
|
if (--ifp->if_pcount > 0)
|
|
return (0);
|
|
ifp->if_flags &= ~IFF_PROMISC;
|
|
}
|
|
ifr.ifr_flags = ifp->if_flags;
|
|
return ((*ifp->if_ioctl)(ifp, SIOCSIFFLAGS, (caddr_t)&ifr));
|
|
}
|
|
#endif
|
|
|
|
#if BSD < 199103
|
|
/*
|
|
* Allocate some memory for bpf. This is temporary SunOS support, and
|
|
* is admittedly a hack.
|
|
* If resources unavaiable, return 0.
|
|
*/
|
|
static caddr_t
|
|
bpf_alloc(size, canwait)
|
|
register int size;
|
|
register int canwait;
|
|
{
|
|
register struct mbuf *m;
|
|
|
|
if ((unsigned)size > (MCLBYTES-8))
|
|
return 0;
|
|
|
|
MGET(m, canwait, MT_DATA);
|
|
if (m == 0)
|
|
return 0;
|
|
if ((unsigned)size > (MLEN-8)) {
|
|
MCLGET(m);
|
|
if (m->m_len != MCLBYTES) {
|
|
m_freem(m);
|
|
return 0;
|
|
}
|
|
}
|
|
*mtod(m, struct mbuf **) = m;
|
|
return mtod(m, caddr_t) + 8;
|
|
}
|
|
#endif
|
|
#endif
|