1/*-
2 * SPDX-License-Identifier: BSD-3-Clause
3 *
4 * Copyright (C) 2002-2003 NetGroup, Politecnico di Torino (Italy)
5 * Copyright (C) 2005-2017 Jung-uk Kim <jkim@FreeBSD.org>
6 * All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 *
12 * 1. Redistributions of source code must retain the above copyright
13 * notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 * notice, this list of conditions and the following disclaimer in the
16 * documentation and/or other materials provided with the distribution.
17 * 3. Neither the name of the Politecnico di Torino nor the names of its
18 * contributors may be used to endorse or promote products derived from
19 * this software without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
22 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
23 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
24 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
25 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
26 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
27 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
28 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
29 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
30 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
31 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
32 */
33
34#include <sys/cdefs.h>
35__FBSDID("$FreeBSD$");
36
37#ifdef _KERNEL
38#include "opt_bpf.h"
39
40#include <sys/param.h>
41#include <sys/kernel.h>
42#include <sys/malloc.h>
43#include <sys/mbuf.h>
44#include <sys/sysctl.h>
45#else
46#include <stdlib.h>
47#include <sys/mman.h>
48#include <sys/param.h>
49#include <sys/types.h>
50#endif
51
52#include <net/bpf.h>
53#include <net/bpf_jitter.h>
54
55static u_int	bpf_jit_accept_all(u_char *, u_int, u_int);
56
57#ifdef _KERNEL
58MALLOC_DEFINE(M_BPFJIT, "BPF_JIT", "BPF JIT compiler");
59
60SYSCTL_NODE(_net, OID_AUTO, bpf_jitter, CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
61    "BPF JIT compiler");
62int bpf_jitter_enable = 1;
63SYSCTL_INT(_net_bpf_jitter, OID_AUTO, enable, CTLFLAG_RW,
64    &bpf_jitter_enable, 0, "enable BPF JIT compiler");
65#endif
66
67bpf_jit_filter *
68bpf_jitter(struct bpf_insn *fp, int nins)
69{
70	bpf_jit_filter *filter;
71
72	/* Allocate the filter structure. */
73#ifdef _KERNEL
74	filter = (struct bpf_jit_filter *)malloc(sizeof(*filter),
75	    M_BPFJIT, M_NOWAIT);
76#else
77	filter = (struct bpf_jit_filter *)malloc(sizeof(*filter));
78#endif
79	if (filter == NULL)
80		return (NULL);
81
82	/* No filter means accept all. */
83	if (fp == NULL || nins == 0) {
84		filter->func = bpf_jit_accept_all;
85		return (filter);
86	}
87
88	/* Create the binary. */
89	if ((filter->func = bpf_jit_compile(fp, nins, &filter->size)) == NULL) {
90#ifdef _KERNEL
91		free(filter, M_BPFJIT);
92#else
93		free(filter);
94#endif
95		return (NULL);
96	}
97
98	return (filter);
99}
100
101void
102bpf_destroy_jit_filter(bpf_jit_filter *filter)
103{
104
105#ifdef _KERNEL
106	if (filter->func != bpf_jit_accept_all)
107		free(filter->func, M_BPFJIT);
108	free(filter, M_BPFJIT);
109#else
110	if (filter->func != bpf_jit_accept_all)
111		munmap(filter->func, filter->size);
112	free(filter);
113#endif
114}
115
116static u_int
117bpf_jit_accept_all(__unused u_char *p, __unused u_int wirelen,
118    __unused u_int buflen)
119{
120
121	return ((u_int)-1);
122}
123