1 /*- 2 * Copyright (C) 2002-2003 NetGroup, Politecnico di Torino (Italy) 3 * Copyright (C) 2005-2017 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/mman.h> 46 #include <sys/param.h> 47 #include <sys/types.h> 48 #endif 49 50 #include <net/bpf.h> 51 #include <net/bpf_jitter.h> 52 53 static u_int bpf_jit_accept_all(u_char *, u_int, u_int); 54 55 #ifdef _KERNEL 56 MALLOC_DEFINE(M_BPFJIT, "BPF_JIT", "BPF JIT compiler"); 57 58 SYSCTL_NODE(_net, OID_AUTO, bpf_jitter, CTLFLAG_RW, 0, "BPF JIT compiler"); 59 int bpf_jitter_enable = 1; 60 SYSCTL_INT(_net_bpf_jitter, OID_AUTO, enable, CTLFLAG_RW, 61 &bpf_jitter_enable, 0, "enable BPF JIT compiler"); 62 #endif 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 #ifdef _KERNEL 71 filter = (struct bpf_jit_filter *)malloc(sizeof(*filter), 72 M_BPFJIT, M_NOWAIT); 73 #else 74 filter = (struct bpf_jit_filter *)malloc(sizeof(*filter)); 75 #endif 76 if (filter == NULL) 77 return (NULL); 78 79 /* No filter means accept all. */ 80 if (fp == NULL || nins == 0) { 81 filter->func = bpf_jit_accept_all; 82 return (filter); 83 } 84 85 /* Create the binary. */ 86 if ((filter->func = bpf_jit_compile(fp, nins, &filter->size)) == NULL) { 87 #ifdef _KERNEL 88 free(filter, M_BPFJIT); 89 #else 90 free(filter); 91 #endif 92 return (NULL); 93 } 94 95 return (filter); 96 } 97 98 void 99 bpf_destroy_jit_filter(bpf_jit_filter *filter) 100 { 101 102 if (filter->func != bpf_jit_accept_all) 103 bpf_jit_free(filter->func, filter->size); 104 #ifdef _KERNEL 105 free(filter, M_BPFJIT); 106 #else 107 free(filter); 108 #endif 109 } 110 111 static u_int 112 bpf_jit_accept_all(__unused u_char *p, __unused u_int wirelen, 113 __unused u_int buflen) 114 { 115 116 return ((u_int)-1); 117 } 118