| 1 | /*- |
| 2 | * SPDX-License-Identifier: BSD-3-Clause |
| 3 | * |
| 4 | * Copyright (C) 2002-2003 NetGroup, Politecnico di Torino (Italy) |
| 5 | * Copyright (C) 2005-2009 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 | #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 | /* |
| 84 | * Declarations for machine-dependent functions. |
| 85 | */ |
| 86 | struct bpf_insn; |
| 87 | |
| 88 | bpf_filter_func bpf_jit_compile(struct bpf_insn *, u_int, size_t *); |
| 89 | |
| 90 | #endif /* _NET_BPF_JITTER_H_ */ |