faa693cdbe
The buffer must be allocated (or even changed) before the interface is set and thus, there is no need to verify if the buffer is in use. MFC after: 2 weeks Sponsored by: Rubicon Communications (Netgate)
220 lines
6.5 KiB
C
220 lines
6.5 KiB
C
/*-
|
|
* Copyright (c) 2007 Seccuris Inc.
|
|
* All rights reserved.
|
|
*
|
|
* This software was developed by Robert N. M. Watson under contract to
|
|
* Seccuris Inc.
|
|
*
|
|
* Redistribution and use in source and binary forms, with or without
|
|
* modification, are permitted provided that the following conditions
|
|
* are met:
|
|
* 1. Redistributions of source code must retain the above copyright
|
|
* notice, this list of conditions and the following disclaimer.
|
|
* 2. Redistributions in binary form must reproduce the above copyright
|
|
* notice, this list of conditions and the following disclaimer in the
|
|
* documentation and/or other materials provided with the distribution.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
|
|
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
|
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
|
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
|
|
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
|
|
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
|
|
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
|
|
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
|
|
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
|
|
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
|
|
* SUCH DAMAGE.
|
|
*
|
|
* Copyright (c) 1990, 1991, 1993
|
|
* The Regents of the University of California. All rights reserved.
|
|
*
|
|
* This code is derived from the Stanford/CMU enet packet filter,
|
|
* (net/enet.c) distributed as part of 4.3BSD, and code contributed
|
|
* to Berkeley by Steven McCanne and Van Jacobson both of Lawrence
|
|
* Berkeley Laboratory.
|
|
*
|
|
* Redistribution and use in source and binary forms, with or without
|
|
* modification, are permitted provided that the following conditions
|
|
* are met:
|
|
* 1. Redistributions of source code must retain the above copyright
|
|
* notice, this list of conditions and the following disclaimer.
|
|
* 2. Redistributions in binary form must reproduce the above copyright
|
|
* notice, this list of conditions and the following disclaimer in the
|
|
* documentation and/or other materials provided with the distribution.
|
|
* 4. Neither the name of the University nor the names of its contributors
|
|
* may be used to endorse or promote products derived from this software
|
|
* without specific prior written permission.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
|
|
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
|
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
|
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
|
|
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
|
|
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
|
|
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
|
|
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
|
|
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
|
|
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
|
|
* SUCH DAMAGE.
|
|
*
|
|
* @(#)bpf.c 8.4 (Berkeley) 1/9/95
|
|
*/
|
|
|
|
#include <sys/cdefs.h>
|
|
__FBSDID("$FreeBSD$");
|
|
|
|
#include "opt_bpf.h"
|
|
|
|
#include <sys/param.h>
|
|
#include <sys/malloc.h>
|
|
#include <sys/mbuf.h>
|
|
#include <sys/socket.h>
|
|
#include <sys/uio.h>
|
|
#include <sys/kernel.h>
|
|
#include <sys/sysctl.h>
|
|
|
|
#include <net/if.h>
|
|
#include <net/bpf.h>
|
|
#include <net/bpf_buffer.h>
|
|
#include <net/bpfdesc.h>
|
|
|
|
/*
|
|
* Implement historical kernel memory buffering model for BPF: two malloc(9)
|
|
* kernel buffers are hung off of the descriptor. The size is fixed prior to
|
|
* attaching to an ifnet, ad cannot be changed after that. read(2) simply
|
|
* copies the data to user space using uiomove(9).
|
|
*/
|
|
|
|
static int bpf_bufsize = 4096;
|
|
SYSCTL_INT(_net_bpf, OID_AUTO, bufsize, CTLFLAG_RW,
|
|
&bpf_bufsize, 0, "Default capture buffer size in bytes");
|
|
static int bpf_maxbufsize = BPF_MAXBUFSIZE;
|
|
SYSCTL_INT(_net_bpf, OID_AUTO, maxbufsize, CTLFLAG_RW,
|
|
&bpf_maxbufsize, 0, "Maximum capture buffer in bytes");
|
|
|
|
/*
|
|
* Simple data copy to the current kernel buffer.
|
|
*/
|
|
void
|
|
bpf_buffer_append_bytes(struct bpf_d *d, caddr_t buf, u_int offset,
|
|
void *src, u_int len)
|
|
{
|
|
u_char *src_bytes;
|
|
|
|
src_bytes = (u_char *)src;
|
|
bcopy(src_bytes, buf + offset, len);
|
|
}
|
|
|
|
/*
|
|
* Scatter-gather data copy from an mbuf chain to the current kernel buffer.
|
|
*/
|
|
void
|
|
bpf_buffer_append_mbuf(struct bpf_d *d, caddr_t buf, u_int offset, void *src,
|
|
u_int len)
|
|
{
|
|
const struct mbuf *m;
|
|
u_char *dst;
|
|
u_int count;
|
|
|
|
m = (struct mbuf *)src;
|
|
dst = (u_char *)buf + offset;
|
|
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;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Free BPF kernel buffers on device close.
|
|
*/
|
|
void
|
|
bpf_buffer_free(struct bpf_d *d)
|
|
{
|
|
|
|
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);
|
|
|
|
#ifdef INVARIANTS
|
|
d->bd_sbuf = d->bd_hbuf = d->bd_fbuf = (caddr_t)~0;
|
|
#endif
|
|
}
|
|
|
|
/*
|
|
* This is a historical initialization that occurs when the BPF descriptor is
|
|
* first opened. It does not imply selection of a buffer mode, so we don't
|
|
* allocate buffers here.
|
|
*/
|
|
void
|
|
bpf_buffer_init(struct bpf_d *d)
|
|
{
|
|
|
|
d->bd_bufsize = bpf_bufsize;
|
|
}
|
|
|
|
/*
|
|
* Allocate or resize buffers.
|
|
*/
|
|
int
|
|
bpf_buffer_ioctl_sblen(struct bpf_d *d, u_int *i)
|
|
{
|
|
u_int size;
|
|
caddr_t fbuf, sbuf;
|
|
|
|
size = *i;
|
|
if (size > bpf_maxbufsize)
|
|
*i = size = bpf_maxbufsize;
|
|
else if (size < BPF_MINBUFSIZE)
|
|
*i = size = BPF_MINBUFSIZE;
|
|
|
|
/* Allocate buffers immediately */
|
|
fbuf = (caddr_t)malloc(size, M_BPF, M_WAITOK);
|
|
sbuf = (caddr_t)malloc(size, M_BPF, M_WAITOK);
|
|
|
|
BPFD_LOCK(d);
|
|
if (d->bd_bif != NULL) {
|
|
/* Interface already attached, unable to change buffers */
|
|
BPFD_UNLOCK(d);
|
|
free(fbuf, M_BPF);
|
|
free(sbuf, M_BPF);
|
|
return (EINVAL);
|
|
}
|
|
|
|
/* Free old buffers if set */
|
|
if (d->bd_fbuf != NULL)
|
|
free(d->bd_fbuf, M_BPF);
|
|
if (d->bd_sbuf != NULL)
|
|
free(d->bd_sbuf, M_BPF);
|
|
|
|
/* Fill in new data */
|
|
d->bd_bufsize = size;
|
|
d->bd_fbuf = fbuf;
|
|
d->bd_sbuf = sbuf;
|
|
|
|
d->bd_hbuf = NULL;
|
|
d->bd_slen = 0;
|
|
d->bd_hlen = 0;
|
|
|
|
BPFD_UNLOCK(d);
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* Copy buffer storage to user space in read().
|
|
*/
|
|
int
|
|
bpf_buffer_uiomove(struct bpf_d *d, caddr_t buf, u_int len, struct uio *uio)
|
|
{
|
|
|
|
return (uiomove(buf, len, uio));
|
|
}
|