1 /*- 2 * Copyright (C) 2002-2003 NetGroup, Politecnico di Torino (Italy) 3 * Copyright (C) 2005-2009 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 * $FreeBSD$ 32 */ 33 34 #ifndef _NET_BPF_JITTER_H_ 35 #define _NET_BPF_JITTER_H_ 36 37 #ifdef _KERNEL 38 MALLOC_DECLARE(M_BPFJIT); 39 #endif 40 41 extern int bpf_jitter_enable; 42 43 /* 44 * Prototype of a filtering function created by the jitter. 45 * 46 * The syntax and the meaning of the parameters is analogous to the one of 47 * bpf_filter(). Notice that the filter is not among the parameters because 48 * it is hardwired in the function. 49 */ 50 typedef u_int (*bpf_filter_func)(u_char *, u_int, u_int); 51 52 /* Structure describing a native filtering program created by the jitter. */ 53 typedef struct bpf_jit_filter { 54 /* The native filtering binary, in the form of a bpf_filter_func. */ 55 bpf_filter_func func; 56 size_t size; 57 } bpf_jit_filter; 58 59 /* 60 * BPF jitter, builds a machine function from a BPF program. 61 * 62 * param fp The BPF pseudo-assembly filter that will be translated 63 * into native code. 64 * param nins Number of instructions of the input filter. 65 * return The bpf_jit_filter structure containing the native filtering 66 * binary. 67 * 68 * bpf_jitter allocates the buffers for the new native filter and 69 * then translates the program pointed by fp calling bpf_jit_compile(). 70 */ 71 bpf_jit_filter *bpf_jitter(struct bpf_insn *fp, int nins); 72 73 /* 74 * Deletes a filtering function that was previously created by bpf_jitter(). 75 * 76 * param filter The filter to destroy. 77 * 78 * This function frees the variuos buffers (code, memory, etc.) associated 79 * with a filtering function. 80 */ 81 void bpf_destroy_jit_filter(bpf_jit_filter *filter); 82 83 #endif /* _NET_BPF_JITTER_H_ */ 84