06302de20d
Previously it may have contained unnecessary (even sensitive) data from the previous allocation. As a (good) side effect, scratch memory may be used to store the previous filter state(s) safely because it is allocated and freed with filter itself. However, use it carefully because bpf_filter(9) does not have this behavior. MFC after: 3 days
142 lines
3.8 KiB
C
142 lines
3.8 KiB
C
/*-
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* Copyright (C) 2002-2003 NetGroup, Politecnico di Torino (Italy)
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* Copyright (C) 2005-2008 Jung-uk Kim <jkim@FreeBSD.org>
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* All rights reserved.
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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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*
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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. Neither the name of the Politecnico di Torino nor the names of its
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* contributors may be used to endorse or promote products derived from
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* this software without specific prior written permission.
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*
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* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
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* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
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* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
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* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
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* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
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* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
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* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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*/
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#include <sys/cdefs.h>
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__FBSDID("$FreeBSD$");
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#ifdef _KERNEL
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#include "opt_bpf.h"
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#include <sys/param.h>
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#include <sys/kernel.h>
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#include <sys/malloc.h>
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#include <sys/mbuf.h>
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#include <sys/sysctl.h>
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#else
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#include <stdlib.h>
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#include <string.h>
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#include <sys/types.h>
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#endif
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#include <net/bpf.h>
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#include <net/bpf_jitter.h>
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bpf_filter_func bpf_jit_compile(struct bpf_insn *, u_int, int *);
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static u_int bpf_jit_accept_all(u_char *, u_int, u_int);
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#ifdef _KERNEL
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MALLOC_DEFINE(M_BPFJIT, "BPF_JIT", "BPF JIT compiler");
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SYSCTL_NODE(_net, OID_AUTO, bpf_jitter, CTLFLAG_RW, 0, "BPF JIT compiler");
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int bpf_jitter_enable = 1;
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SYSCTL_INT(_net_bpf_jitter, OID_AUTO, enable, CTLFLAG_RW,
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&bpf_jitter_enable, 0, "enable BPF JIT compiler");
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bpf_jit_filter *
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bpf_jitter(struct bpf_insn *fp, int nins)
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{
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bpf_jit_filter *filter;
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/* Allocate the filter structure */
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filter = (struct bpf_jit_filter *)malloc(sizeof(*filter),
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M_BPFJIT, M_NOWAIT | M_ZERO);
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if (filter == NULL)
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return (NULL);
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/* No filter means accept all */
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if (fp == NULL || nins == 0) {
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filter->func = bpf_jit_accept_all;
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return (filter);
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}
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/* Create the binary */
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if ((filter->func = bpf_jit_compile(fp, nins, filter->mem)) == NULL) {
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free(filter, M_BPFJIT);
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return (NULL);
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}
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return (filter);
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}
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void
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bpf_destroy_jit_filter(bpf_jit_filter *filter)
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{
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if (filter->func != bpf_jit_accept_all)
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free(filter->func, M_BPFJIT);
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free(filter, M_BPFJIT);
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}
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#else
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bpf_jit_filter *
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bpf_jitter(struct bpf_insn *fp, int nins)
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{
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bpf_jit_filter *filter;
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/* Allocate the filter structure */
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filter = (struct bpf_jit_filter *)malloc(sizeof(*filter));
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if (filter == NULL)
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return (NULL);
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memset(filter, 0, sizeof(*filter));
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/* No filter means accept all */
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if (fp == NULL || nins == 0) {
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filter->func = bpf_jit_accept_all;
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return (filter);
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}
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/* Create the binary */
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if ((filter->func = bpf_jit_compile(fp, nins, filter->mem)) == NULL) {
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free(filter);
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return (NULL);
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}
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return (filter);
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}
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void
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bpf_destroy_jit_filter(bpf_jit_filter *filter)
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{
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if (filter->func != bpf_jit_accept_all)
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free(filter->func);
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free(filter);
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}
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#endif
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static u_int
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bpf_jit_accept_all(__unused u_char *p, __unused u_int wirelen,
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__unused u_int buflen)
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{
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return ((u_int)-1);
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}
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