NetBSD/sys/net/bpf_jit.c
rmind 1f86dc56b4 Add BPF JIT compiler, currently supporting amd64 and i386. Code obtained
from FreeBSD.  Also, make few BPF fixes and simplifications while here.
Note that bpf_jit_enable is false for now.

OK dyoung@, some feedback from matt@
2012-08-01 23:24:28 +00:00

143 lines
3.7 KiB
C

/* $NetBSD: bpf_jit.c,v 1.1 2012/08/01 23:24:29 rmind Exp $ */
/*-
* Copyright (C) 2002-2003 NetGroup, Politecnico di Torino (Italy)
* Copyright (C) 2005-2009 Jung-uk Kim <jkim@FreeBSD.org>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the Politecnico di Torino 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 COPYRIGHT HOLDERS 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 COPYRIGHT
* OWNER 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.
*
* $FreeBSD: src/sys/net/bpf_jitter.c,v 1.11 2009/11/20 18:49:20 jkim Exp $
*/
#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: bpf_jit.c,v 1.1 2012/08/01 23:24:29 rmind Exp $");
#ifdef _KERNEL
#if defined(_KERNEL_OPT)
#include "opt_bpf.h"
#endif
#include <sys/param.h>
#include <sys/kernel.h>
#include <sys/mbuf.h>
#include <sys/sysctl.h>
#else
#include <stdlib.h>
#include <string.h>
#include <sys/mman.h>
#include <sys/param.h>
#include <sys/types.h>
#endif
#include <net/bpf.h>
#include <net/bpf_jit.h>
bpf_filter_func bpf_jit_compile(struct bpf_insn *, u_int, size_t *);
static u_int bpf_jit_accept_all(u_char *, u_int, u_int);
#ifdef _KERNEL
bpf_jit_filter *
bpf_jit(struct bpf_insn *fp, int nins)
{
bpf_jit_filter *filter;
/* Allocate the filter structure */
filter = malloc(sizeof(*filter), M_TEMP, M_NOWAIT);
if (filter == NULL)
return (NULL);
/* No filter means accept all */
if (fp == NULL || nins == 0) {
filter->func = bpf_jit_accept_all;
return (filter);
}
/* Create the binary */
if ((filter->func = bpf_jit_compile(fp, nins, &filter->size)) == NULL) {
free(filter, M_TEMP);
return (NULL);
}
return (filter);
}
void
bpf_destroy_jit_filter(bpf_jit_filter *filter)
{
if (filter->func != bpf_jit_accept_all)
free(filter->func, M_TEMP);
free(filter, M_TEMP);
}
#else
bpf_jit_filter *
bpf_jit(struct bpf_insn *fp, int nins)
{
bpf_jit_filter *filter;
/* Allocate the filter structure */
filter = (struct bpf_jit_filter *)malloc(sizeof(*filter));
if (filter == NULL)
return (NULL);
/* No filter means accept all */
if (fp == NULL || nins == 0) {
filter->func = bpf_jit_accept_all;
return (filter);
}
/* Create the binary */
if ((filter->func = bpf_jit_compile(fp, nins, &filter->size)) == NULL) {
free(filter);
return (NULL);
}
return (filter);
}
void
bpf_destroy_jit_filter(bpf_jit_filter *filter)
{
if (filter->func != bpf_jit_accept_all)
munmap(filter->func, filter->size);
free(filter);
}
#endif
static u_int
bpf_jit_accept_all(__unused u_char *p, __unused u_int wirelen,
__unused u_int buflen)
{
return ((u_int)-1);
}