| /* |
| * dhcpcd - DHCP client daemon |
| * Copyright (c) 2006-2008 Roy Marples <roy@marples.name> |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions |
| * are met: |
| * 1. Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * 2. Redistributions in binary form must reproduce the above copyright |
| * notice, this list of conditions and the following disclaimer in the |
| * documentation and/or other materials provided with the distribution. |
| * |
| * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND |
| * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
| * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE |
| * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
| * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
| * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
| * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
| * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
| * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
| * SUCH DAMAGE. |
| */ |
| |
| #ifndef BPF_ETHCOOK |
| # define BPF_ETHCOOK 0 |
| #endif |
| #ifndef BPF_WHOLEPACKET |
| # define BPF_WHOLEPACKET ~0U |
| #endif |
| static const struct bpf_insn arp_bpf_filter [] = { |
| #ifndef BPF_SKIPTYPE |
| /* Make sure this is an ARP packet... */ |
| BPF_STMT(BPF_LD + BPF_H + BPF_ABS, 12), |
| BPF_JUMP(BPF_JMP + BPF_JEQ + BPF_K, ETHERTYPE_ARP, 0, 3), |
| #endif |
| /* Make sure this is an ARP REQUEST... */ |
| BPF_STMT(BPF_LD + BPF_H + BPF_ABS, 20 + BPF_ETHCOOK), |
| BPF_JUMP(BPF_JMP + BPF_JEQ + BPF_K, ARPOP_REQUEST, 2, 0), |
| /* or ARP REPLY... */ |
| BPF_STMT(BPF_LD + BPF_H + BPF_ABS, 20 + BPF_ETHCOOK), |
| BPF_JUMP(BPF_JMP + BPF_JEQ + BPF_K, ARPOP_REPLY, 0, 1), |
| /* If we passed all the tests, ask for the whole packet. */ |
| BPF_STMT(BPF_RET + BPF_K, BPF_WHOLEPACKET), |
| /* Otherwise, drop it. */ |
| BPF_STMT(BPF_RET + BPF_K, 0), |
| }; |
| #define arp_bpf_filter_len sizeof(arp_bpf_filter) / sizeof(arp_bpf_filter[0]) |
| |
| |
| /* dhcp_bpf_filter taken from bpf.c in dhcp-3.1.0 |
| * |
| * Copyright (c) 2004,2007 by Internet Systems Consortium, Inc. ("ISC") |
| * Copyright (c) 1996-2003 by Internet Software Consortium |
| * |
| * Permission to use, copy, modify, and distribute this software for any |
| * purpose with or without fee is hereby granted, provided that the above |
| * copyright notice and this permission notice appear in all copies. |
| * |
| * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES |
| * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF |
| * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR |
| * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES |
| * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN |
| * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT |
| * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. |
| * |
| * Internet Systems Consortium, Inc. |
| * 950 Charter Street |
| * Redwood City, CA 94063 |
| * <info@isc.org> |
| * http://www.isc.org/ |
| */ |
| |
| static const struct bpf_insn dhcp_bpf_filter [] = { |
| #ifndef BPF_SKIPTYPE |
| /* Make sure this is an IP packet... */ |
| BPF_STMT(BPF_LD + BPF_H + BPF_ABS, 12), |
| BPF_JUMP(BPF_JMP + BPF_JEQ + BPF_K, ETHERTYPE_IP, 0, 8), |
| #endif |
| /* Make sure it's a UDP packet... */ |
| BPF_STMT(BPF_LD + BPF_B + BPF_ABS, 23 + BPF_ETHCOOK), |
| BPF_JUMP(BPF_JMP + BPF_JEQ + BPF_K, IPPROTO_UDP, 0, 6), |
| /* Make sure this isn't a fragment... */ |
| BPF_STMT(BPF_LD + BPF_H + BPF_ABS, 20 + BPF_ETHCOOK), |
| BPF_JUMP(BPF_JMP + BPF_JSET + BPF_K, 0x1fff, 4, 0), |
| /* Get the IP header length... */ |
| BPF_STMT(BPF_LDX + BPF_B + BPF_MSH, 14 + BPF_ETHCOOK), |
| /* Make sure it's to the right port... */ |
| BPF_STMT(BPF_LD + BPF_H + BPF_IND, 16 + BPF_ETHCOOK), |
| BPF_JUMP(BPF_JMP + BPF_JEQ + BPF_K, DHCP_CLIENT_PORT, 0, 1), |
| /* If we passed all the tests, ask for the whole packet. */ |
| BPF_STMT(BPF_RET + BPF_K, BPF_WHOLEPACKET), |
| /* Otherwise, drop it. */ |
| BPF_STMT(BPF_RET + BPF_K, 0), |
| }; |
| #define dhcp_bpf_filter_len sizeof(dhcp_bpf_filter) / sizeof(dhcp_bpf_filter[0]) |
