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 <string.h> 46 #include <sys/types.h> 47 #endif 48 49 #include <net/bpf.h> 50 #include <net/bpf_jitter.h> 51 52 bpf_filter_func bpf_jit_compile(struct bpf_insn *, u_int, int *); 53 54 static u_int bpf_jit_accept_all(u_char *, u_int, u_int); 55 56 #ifdef _KERNEL 57 MALLOC_DEFINE(M_BPFJIT, "BPF_JIT", "BPF JIT compiler"); 58 59 SYSCTL_NODE(_net, OID_AUTO, bpf_jitter, CTLFLAG_RW, 0, "BPF JIT compiler"); 60 int bpf_jitter_enable = 1; 61 SYSCTL_INT(_net_bpf_jitter, OID_AUTO, enable, CTLFLAG_RW, 62 &bpf_jitter_enable, 0, "enable BPF JIT compiler"); 63 64 bpf_jit_filter * 65 bpf_jitter(struct bpf_insn *fp, int nins) 66 { 67 bpf_jit_filter *filter; 68 69 /* Allocate the filter structure */ 70 filter = (struct bpf_jit_filter *)malloc(sizeof(*filter), 71 M_BPFJIT, M_NOWAIT | M_ZERO); 72 if (filter == NULL) 73 return (NULL); 74 75 /* No filter means accept all */ 76 if (fp == NULL || nins == 0) { 77 filter->func = bpf_jit_accept_all; 78 return (filter); 79 } 80 81 /* Create the binary */ 82 if ((filter->func = bpf_jit_compile(fp, nins, filter->mem)) == NULL) { 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 if (filter->func != bpf_jit_accept_all) 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 memset(filter, 0, sizeof(*filter)); 109 110 /* No filter means accept all */ 111 if (fp == NULL || nins == 0) { 112 filter->func = bpf_jit_accept_all; 113 return (filter); 114 } 115 116 /* Create the binary */ 117 if ((filter->func = bpf_jit_compile(fp, nins, filter->mem)) == NULL) { 118 free(filter); 119 return (NULL); 120 } 121 122 return (filter); 123 } 124 125 void 126 bpf_destroy_jit_filter(bpf_jit_filter *filter) 127 { 128 129 if (filter->func != bpf_jit_accept_all) 130 free(filter->func); 131 free(filter); 132 } 133 #endif 134 135 static u_int 136 bpf_jit_accept_all(__unused u_char *p, __unused u_int wirelen, 137 __unused u_int buflen) 138 { 139 140 return ((u_int)-1); 141 } 142