1 /* 2 * dhcpcd - DHCP client daemon 3 * Copyright (c) 2006-2018 Roy Marples <roy@marples.name> 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 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 18 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 25 * SUCH DAMAGE. 26 */ 27 28 #ifndef ARP_H 29 #define ARP_H 30 31 /* ARP timings from RFC5227 */ 32 #define PROBE_WAIT 1 33 #define PROBE_NUM 3 34 #define PROBE_MIN 1 35 #define PROBE_MAX 2 36 #define ANNOUNCE_WAIT 2 37 #define ANNOUNCE_NUM 2 38 #define ANNOUNCE_INTERVAL 2 39 #define MAX_CONFLICTS 10 40 #define RATE_LIMIT_INTERVAL 60 41 #define DEFEND_INTERVAL 10 42 43 #include "dhcpcd.h" 44 #include "if.h" 45 46 #ifdef IN_IFF_DUPLICATED 47 /* NetBSD gained RFC 5227 support in the kernel. 48 * This means dhcpcd doesn't need ARP except for ARPing support. */ 49 #if defined(__NetBSD_Version__) && __NetBSD_Version__ >= 799003900 50 #define KERNEL_RFC5227 51 #endif 52 #endif 53 54 struct arp_msg { 55 uint16_t op; 56 unsigned char sha[HWADDR_LEN]; 57 struct in_addr sip; 58 unsigned char tha[HWADDR_LEN]; 59 struct in_addr tip; 60 }; 61 62 struct arp_state { 63 TAILQ_ENTRY(arp_state) next; 64 struct interface *iface; 65 66 void (*probed_cb)(struct arp_state *); 67 void (*announced_cb)(struct arp_state *); 68 void (*conflicted_cb)(struct arp_state *, const struct arp_msg *); 69 void (*free_cb)(struct arp_state *); 70 71 struct in_addr addr; 72 int probes; 73 int claims; 74 struct in_addr failed; 75 }; 76 TAILQ_HEAD(arp_statehead, arp_state); 77 78 struct iarp_state { 79 int bpf_fd; 80 unsigned int bpf_flags; 81 struct arp_statehead arp_states; 82 }; 83 84 #define ARP_STATE(ifp) \ 85 ((struct iarp_state *)(ifp)->if_data[IF_DATA_ARP]) 86 #define ARP_CSTATE(ifp) \ 87 ((const struct iarp_state *)(ifp)->if_data[IF_DATA_ARP]) 88 89 #ifdef ARP 90 int arp_open(struct interface *); 91 ssize_t arp_request(const struct interface *, in_addr_t, in_addr_t); 92 void arp_probe(struct arp_state *); 93 void arp_close(struct interface *); 94 void arp_report_conflicted(const struct arp_state *, const struct arp_msg *); 95 struct arp_state *arp_new(struct interface *, const struct in_addr *); 96 struct arp_state *arp_find(struct interface *, const struct in_addr *); 97 void arp_announce(struct arp_state *); 98 void arp_announceaddr(struct dhcpcd_ctx *, struct in_addr *); 99 void arp_ifannounceaddr(struct interface *, struct in_addr *); 100 void arp_cancel(struct arp_state *); 101 void arp_free(struct arp_state *); 102 void arp_free_but(struct arp_state *); 103 void arp_drop(struct interface *); 104 105 void arp_handleifa(int, struct ipv4_addr *); 106 #endif /* ARP */ 107 #endif /* ARP_H */ 108