xref: /freebsd/sys/net/bpf_jitter.c (revision 6356dba0b403daa023dec24559ab1f8e602e4f14)
1 /*-
2  * Copyright (C) 2002-2003 NetGroup, Politecnico di Torino (Italy)
3  * Copyright (C) 2005-2008 Jung-uk Kim <jkim@FreeBSD.org>
4  * All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  *
10  * 1. Redistributions of source code must retain the above copyright
11  * notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  * notice, this list of conditions and the following disclaimer in the
14  * documentation and/or other materials provided with the distribution.
15  * 3. Neither the name of the Politecnico di Torino nor the names of its
16  * contributors may be used to endorse or promote products derived from
17  * this software without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
20  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
21  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
22  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
23  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
24  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
25  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
26  * DATA, OR PROFITS; OR BUSINESS intERRUPTION) HOWEVER CAUSED AND ON ANY
27  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
28  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
29  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
30  */
31 
32 #include <sys/cdefs.h>
33 __FBSDID("$FreeBSD$");
34 
35 #ifdef _KERNEL
36 #include "opt_bpf.h"
37 
38 #include <sys/param.h>
39 #include <sys/kernel.h>
40 #include <sys/malloc.h>
41 #include <sys/mbuf.h>
42 #include <sys/sysctl.h>
43 #else
44 #include <stdlib.h>
45 #include <sys/types.h>
46 #endif
47 
48 #include <net/bpf.h>
49 #include <net/bpf_jitter.h>
50 
51 bpf_filter_func	bpf_jit_compile(struct bpf_insn *, u_int, int *);
52 
53 #ifdef _KERNEL
54 MALLOC_DEFINE(M_BPFJIT, "BPF_JIT", "BPF JIT compiler");
55 
56 SYSCTL_NODE(_net, OID_AUTO, bpf_jitter, CTLFLAG_RW, 0, "BPF JIT compiler");
57 int bpf_jitter_enable = 1;
58 SYSCTL_INT(_net_bpf_jitter, OID_AUTO, enable, CTLFLAG_RW,
59     &bpf_jitter_enable, 0, "enable BPF JIT compiler");
60 
61 bpf_jit_filter *
62 bpf_jitter(struct bpf_insn *fp, int nins)
63 {
64 	bpf_jit_filter *filter;
65 
66 	/* Allocate the filter structure */
67 	filter = (struct bpf_jit_filter *)malloc(sizeof(*filter),
68 	    M_BPFJIT, M_NOWAIT);
69 	if (filter == NULL)
70 		return (NULL);
71 
72 	/* Allocate the filter's memory */
73 	filter->mem = (int *)malloc(BPF_MEMWORDS * sizeof(int),
74 	    M_BPFJIT, M_NOWAIT);
75 	if (filter->mem == NULL) {
76 		free(filter, M_BPFJIT);
77 		return (NULL);
78 	}
79 
80 	/* Create the binary */
81 	if ((filter->func = bpf_jit_compile(fp, nins, filter->mem)) == NULL) {
82 		free(filter->mem, M_BPFJIT);
83 		free(filter, M_BPFJIT);
84 		return (NULL);
85 	}
86 
87 	return (filter);
88 }
89 
90 void
91 bpf_destroy_jit_filter(bpf_jit_filter *filter)
92 {
93 
94 	free(filter->mem, M_BPFJIT);
95 	free(filter->func, M_BPFJIT);
96 	free(filter, M_BPFJIT);
97 }
98 #else
99 bpf_jit_filter *
100 bpf_jitter(struct bpf_insn *fp, int nins)
101 {
102 	bpf_jit_filter *filter;
103 
104 	/* Allocate the filter structure */
105 	filter = (struct bpf_jit_filter *)malloc(sizeof(*filter));
106 	if (filter == NULL)
107 		return (NULL);
108 
109 	/* Allocate the filter's memory */
110 	filter->mem = (int *)malloc(BPF_MEMWORDS * sizeof(int));
111 	if (filter->mem == NULL) {
112 		free(filter);
113 		return (NULL);
114 	}
115 
116 	/* Create the binary */
117 	if ((filter->func = bpf_jit_compile(fp, nins, filter->mem)) == NULL) {
118 		free(filter->mem);
119 		free(filter);
120 		return (NULL);
121 	}
122 
123 	return (filter);
124 }
125 
126 void
127 bpf_destroy_jit_filter(bpf_jit_filter *filter)
128 {
129 
130 	free(filter->mem);
131 	free(filter->func);
132 	free(filter);
133 }
134 #endif
135