mirror of
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a3272e3ce3
debug.bpf_bufsize is now net.bpf.bufsize debug.bpf_maxbufsize is now net.bpf.maxbufsize -move function prototypes for bpf_drvinit and bpf_clone up to the top of the file with the others -assert bpfd lock in catchpacket() and bpf_wakeup() MFC after: 2 weeks
1699 lines
35 KiB
C
1699 lines
35 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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* 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 8.4 (Berkeley) 1/9/95
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*
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* $FreeBSD$
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*/
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#include "opt_bpf.h"
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#include "opt_mac.h"
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#include "opt_netgraph.h"
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#include <sys/types.h>
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#include <sys/param.h>
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#include <sys/systm.h>
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#include <sys/conf.h>
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#include <sys/fcntl.h>
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#include <sys/mac.h>
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#include <sys/malloc.h>
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#include <sys/mbuf.h>
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#include <sys/time.h>
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#include <sys/proc.h>
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#include <sys/signalvar.h>
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#include <sys/filio.h>
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#include <sys/sockio.h>
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#include <sys/ttycom.h>
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#include <sys/uio.h>
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#include <sys/event.h>
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#include <sys/file.h>
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#include <sys/poll.h>
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#include <sys/proc.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 <netinet/in.h>
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#include <netinet/if_ether.h>
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#include <sys/kernel.h>
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#include <sys/sysctl.h>
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static MALLOC_DEFINE(M_BPF, "BPF", "BPF data");
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#if defined(DEV_BPF) || defined(NETGRAPH_BPF)
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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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SYSCTL_NODE(_net, OID_AUTO, bpf, CTLFLAG_RW, 0, "bpf sysctl");
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static int bpf_bufsize = 4096;
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SYSCTL_INT(_net_bpf, OID_AUTO, bufsize, CTLFLAG_RW,
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&bpf_bufsize, 0, "");
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static int bpf_maxbufsize = BPF_MAXBUFSIZE;
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SYSCTL_INT(_net_bpf, OID_AUTO, maxbufsize, CTLFLAG_RW,
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&bpf_maxbufsize, 0, "");
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/*
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* bpf_iflist is a list of BPF interface structures, each corresponding to a
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* specific DLT. The same network interface might have several BPF interface
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* structures registered by different layers in the stack (i.e., 802.11
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* frames, ethernet frames, etc).
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*/
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static LIST_HEAD(, bpf_if) bpf_iflist;
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static struct mtx bpf_mtx; /* bpf global lock */
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static int bpf_allocbufs(struct bpf_d *);
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static void bpf_attachd(struct bpf_d *d, struct bpf_if *bp);
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static void bpf_detachd(struct bpf_d *d);
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static void bpf_freed(struct bpf_d *);
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static void bpf_mcopy(const void *, void *, size_t);
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static int bpf_movein(struct uio *, int,
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struct mbuf **, struct sockaddr *, int *);
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static int bpf_setif(struct bpf_d *, struct ifreq *);
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static void bpf_timed_out(void *);
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static __inline void
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bpf_wakeup(struct bpf_d *);
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static void catchpacket(struct bpf_d *, u_char *, u_int,
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u_int, void (*)(const void *, void *, size_t));
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static void reset_d(struct bpf_d *);
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static int bpf_setf(struct bpf_d *, struct bpf_program *);
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static int bpf_getdltlist(struct bpf_d *, struct bpf_dltlist *);
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static int bpf_setdlt(struct bpf_d *, u_int);
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static void filt_bpfdetach(struct knote *);
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static int filt_bpfread(struct knote *, long);
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static void bpf_drvinit(void *);
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static void bpf_clone(void *, char *, int, struct cdev **);
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static d_open_t bpfopen;
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static d_close_t bpfclose;
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static d_read_t bpfread;
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static d_write_t bpfwrite;
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static d_ioctl_t bpfioctl;
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static d_poll_t bpfpoll;
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static d_kqfilter_t bpfkqfilter;
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static struct cdevsw bpf_cdevsw = {
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.d_version = D_VERSION,
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.d_flags = D_NEEDGIANT,
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.d_open = bpfopen,
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.d_close = bpfclose,
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.d_read = bpfread,
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.d_write = bpfwrite,
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.d_ioctl = bpfioctl,
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.d_poll = bpfpoll,
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.d_name = "bpf",
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.d_kqfilter = bpfkqfilter,
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};
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static struct filterops bpfread_filtops =
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{ 1, NULL, filt_bpfdetach, filt_bpfread };
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static int
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bpf_movein(uio, linktype, mp, sockp, datlen)
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struct uio *uio;
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int linktype, *datlen;
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struct mbuf **mp;
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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 = ETHER_HDR_LEN;
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break;
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case DLT_FDDI:
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sockp->sa_family = AF_IMPLINK;
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hlen = 0;
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break;
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case DLT_RAW:
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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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case DLT_ATM_RFC1483:
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/*
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* en atm driver requires 4-byte atm pseudo header.
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* though it isn't standard, vpi:vci needs to be
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* specified anyway.
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*/
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sockp->sa_family = AF_UNSPEC;
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hlen = 12; /* XXX 4(ATM_PH) + 3(LLC) + 5(SNAP) */
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break;
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case DLT_PPP:
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sockp->sa_family = AF_UNSPEC;
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hlen = 4; /* This should match PPP_HDRLEN */
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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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if (len > MHLEN) {
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m = m_getcl(M_TRYWAIT, MT_DATA, M_PKTHDR);
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} else {
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MGETHDR(m, M_TRYWAIT, MT_DATA);
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}
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if (m == NULL)
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return (ENOBUFS);
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m->m_pkthdr.len = m->m_len = len;
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m->m_pkthdr.rcvif = NULL;
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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_pkthdr.len -= hlen;
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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(sockp->sa_data, hlen, 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, void *), len - hlen, 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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*/
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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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BPFIF_LOCK(bp);
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d->bd_bif = bp;
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LIST_INSERT_HEAD(&bp->bif_dlist, d, bd_next);
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*bp->bif_driverp = bp;
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BPFIF_UNLOCK(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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int error;
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struct bpf_if *bp;
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struct ifnet *ifp;
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bp = d->bd_bif;
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BPFIF_LOCK(bp);
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BPFD_LOCK(d);
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ifp = d->bd_bif->bif_ifp;
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/*
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* Remove d from the interface's descriptor list.
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*/
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LIST_REMOVE(d, bd_next);
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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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if (LIST_EMPTY(&bp->bif_dlist))
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*bp->bif_driverp = NULL;
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d->bd_bif = NULL;
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BPFD_UNLOCK(d);
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BPFIF_UNLOCK(bp);
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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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error = ifpromisc(ifp, 0);
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if (error != 0 && error != ENXIO) {
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/*
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* ENXIO can happen if a pccard is unplugged
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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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if_printf(bp->bif_ifp,
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"bpf_detach: ifpromisc failed (%d)\n", error);
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}
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}
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}
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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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static int
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bpfopen(dev, flags, fmt, td)
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struct cdev *dev;
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int flags;
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int fmt;
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struct thread *td;
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{
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struct bpf_d *d;
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mtx_lock(&bpf_mtx);
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d = dev->si_drv1;
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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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if (d != NULL) {
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mtx_unlock(&bpf_mtx);
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return (EBUSY);
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}
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dev->si_drv1 = (struct bpf_d *)~0; /* mark device in use */
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mtx_unlock(&bpf_mtx);
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if ((dev->si_flags & SI_NAMED) == 0)
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make_dev(&bpf_cdevsw, minor(dev), UID_ROOT, GID_WHEEL, 0600,
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"bpf%d", dev2unit(dev));
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MALLOC(d, struct bpf_d *, sizeof(*d), M_BPF, M_WAITOK | M_ZERO);
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dev->si_drv1 = d;
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d->bd_bufsize = bpf_bufsize;
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d->bd_sig = SIGIO;
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d->bd_seesent = 1;
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#ifdef MAC
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mac_init_bpfdesc(d);
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mac_create_bpfdesc(td->td_ucred, d);
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#endif
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mtx_init(&d->bd_mtx, devtoname(dev), "bpf cdev lock", MTX_DEF);
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callout_init(&d->bd_callout, NET_CALLOUT_MPSAFE);
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knlist_init(&d->bd_sel.si_note, &d->bd_mtx);
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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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static int
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bpfclose(dev, flags, fmt, td)
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struct cdev *dev;
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int flags;
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int fmt;
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struct thread *td;
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{
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struct bpf_d *d = dev->si_drv1;
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BPFD_LOCK(d);
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if (d->bd_state == BPF_WAITING)
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callout_stop(&d->bd_callout);
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d->bd_state = BPF_IDLE;
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BPFD_UNLOCK(d);
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funsetown(&d->bd_sigio);
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mtx_lock(&bpf_mtx);
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if (d->bd_bif)
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bpf_detachd(d);
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mtx_unlock(&bpf_mtx);
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selwakeuppri(&d->bd_sel, PRINET);
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#ifdef MAC
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mac_destroy_bpfdesc(d);
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#endif /* MAC */
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knlist_destroy(&d->bd_sel.si_note);
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bpf_freed(d);
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dev->si_drv1 = NULL;
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free(d, M_BPF);
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return (0);
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}
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|
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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 = NULL;
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/*
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* bpfread - read next chunk of packets from buffers
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*/
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static int
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bpfread(dev, uio, ioflag)
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struct cdev *dev;
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struct uio *uio;
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int ioflag;
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{
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struct bpf_d *d = dev->si_drv1;
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int timed_out;
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int error;
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|
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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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|
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BPFD_LOCK(d);
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if (d->bd_state == BPF_WAITING)
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callout_stop(&d->bd_callout);
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timed_out = (d->bd_state == BPF_TIMED_OUT);
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d->bd_state = BPF_IDLE;
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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 == NULL) {
|
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if ((d->bd_immediate || timed_out) && 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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|
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/*
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* No data is available, check to see if the bpf device
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* 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) {
|
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BPFD_UNLOCK(d);
|
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return (ENXIO);
|
|
}
|
|
|
|
if (ioflag & O_NONBLOCK) {
|
|
BPFD_UNLOCK(d);
|
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return (EWOULDBLOCK);
|
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}
|
|
error = msleep(d, &d->bd_mtx, PRINET|PCATCH,
|
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"bpf", d->bd_rtout);
|
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if (error == EINTR || error == ERESTART) {
|
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BPFD_UNLOCK(d);
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return (error);
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}
|
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if (error == EWOULDBLOCK) {
|
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/*
|
|
* On a timeout, return what's in the buffer,
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|
* which may be nothing. If there is something
|
|
* in the store buffer, we can rotate the buffers.
|
|
*/
|
|
if (d->bd_hbuf)
|
|
/*
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|
* We filled up the buffer in between
|
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* getting the timeout and arriving
|
|
* here, so we don't need to rotate.
|
|
*/
|
|
break;
|
|
|
|
if (d->bd_slen == 0) {
|
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BPFD_UNLOCK(d);
|
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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;
|
|
int datlen;
|
|
|
|
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, &m, &dst, &datlen);
|
|
if (error)
|
|
return (error);
|
|
|
|
if (datlen > ifp->if_mtu) {
|
|
m_freem(m);
|
|
return (EMSGSIZE);
|
|
}
|
|
|
|
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;
|
|
}
|
|
|
|
/*
|
|
* 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.
|
|
* BIOCGHDRCMPLT Get "header already complete" flag
|
|
* BIOCSHDRCMPLT Set "header already complete" flag
|
|
* BIOCGSEESENT Get "see packets sent" flag
|
|
* BIOCSSEESENT Set "see packets sent" 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);
|
|
|
|
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:
|
|
error = bpf_setf(d, (struct bpf_program *)addr);
|
|
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;
|
|
|
|
/*
|
|
* 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)
|
|
struct bpf_d *d;
|
|
struct bpf_program *fp;
|
|
{
|
|
struct bpf_insn *fcode, *old;
|
|
u_int flen, size;
|
|
|
|
if (fp->bf_insns == NULL) {
|
|
if (fp->bf_len != 0)
|
|
return (EINVAL);
|
|
BPFD_LOCK(d);
|
|
old = d->bd_filter;
|
|
d->bd_filter = 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);
|
|
old = d->bd_filter;
|
|
d->bd_filter = 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 != (struct bpf_if **)&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_filter, pkt, pktlen, pktlen);
|
|
if (slen != 0) {
|
|
#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_filter, (u_char *)m, pktlen, 0);
|
|
if (slen != 0)
|
|
#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_filter, (u_char *)&mb, pktlen, 0);
|
|
if (slen != 0)
|
|
#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_filter)
|
|
free((caddr_t)d->bd_filter, 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, name, namelen, dev)
|
|
void *arg;
|
|
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);
|
|
}
|
|
|
|
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 */
|