1 /* $OpenBSD: probe.c,v 1.5 2023/06/26 10:08:56 claudio Exp $ */ 2 3 /* 4 * Copyright (c) 2005, 2006 Esben Norby <norby@openbsd.org> 5 * 6 * Permission to use, copy, modify, and distribute this software for any 7 * purpose with or without fee is hereby granted, provided that the above 8 * copyright notice and this permission notice appear in all copies. 9 * 10 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES 11 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 12 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR 13 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 14 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 15 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF 16 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 17 */ 18 19 #include <sys/types.h> 20 #include <sys/socket.h> 21 #include <netinet/in.h> 22 #include <arpa/inet.h> 23 #include <sys/time.h> 24 #include <stdlib.h> 25 #include <string.h> 26 #include <event.h> 27 28 #include "igmp.h" 29 #include "dvmrpd.h" 30 #include "dvmrp.h" 31 #include "log.h" 32 #include "dvmrpe.h" 33 34 extern struct dvmrpd_conf *deconf; 35 36 /* DVMRP probe packet handling */ 37 int 38 send_probe(struct iface *iface) 39 { 40 struct sockaddr_in dst; 41 struct ibuf *buf; 42 struct nbr *nbr; 43 int ret = 0; 44 45 if (iface->passive) 46 return (0); 47 48 if ((buf = ibuf_open(iface->mtu - sizeof(struct ip))) == NULL) 49 fatal("send_probe"); 50 51 /* DVMRP header */ 52 if (gen_dvmrp_hdr(buf, iface, DVMRP_CODE_PROBE)) 53 goto fail; 54 55 /* generation ID */ 56 ibuf_add(buf, &iface->gen_id, sizeof(iface->gen_id)); 57 58 /* generate neighbor list */ 59 LIST_FOREACH(nbr, &iface->nbr_list, entry) { 60 if (nbr->state > NBR_STA_DOWN) 61 ibuf_add(buf, &nbr->id, sizeof(nbr->id)); 62 } 63 64 /* set destination address */ 65 dst.sin_family = AF_INET; 66 dst.sin_len = sizeof(struct sockaddr_in); 67 inet_aton(AllDVMRPRouters, &dst.sin_addr); 68 69 ret = send_packet(iface, buf, &dst); 70 ibuf_free(buf); 71 return (ret); 72 fail: 73 log_warn("send_probe"); 74 ibuf_free(buf); 75 return (-1); 76 } 77 78 void 79 recv_probe(struct iface *iface, struct in_addr src, u_int32_t src_ip, 80 u_int8_t capabilities, char *buf, u_int16_t len) 81 { 82 struct nbr *nbr = NULL; 83 u_int32_t gen_id; 84 u_int32_t nbr_id; 85 86 LIST_FOREACH(nbr, &iface->nbr_list, entry) { 87 if (nbr->id.s_addr == src_ip) 88 break; 89 } 90 91 memcpy(&gen_id, buf, sizeof(gen_id)); 92 len -= sizeof(gen_id); 93 buf += sizeof(gen_id); 94 95 if (!nbr) { 96 nbr = nbr_new(src_ip, iface, 0); 97 nbr->gen_id = gen_id; 98 nbr->capabilities = capabilities; 99 nbr->addr = src; 100 } 101 102 nbr_fsm(nbr, NBR_EVT_PROBE_RCVD); 103 104 if ((nbr->gen_id != gen_id) || (nbr->capabilities != capabilities)) { 105 if (!nbr->compat) 106 nbr_fsm(nbr, NBR_EVT_1_WAY_RCVD); 107 nbr->gen_id = gen_id; 108 nbr->capabilities = capabilities; 109 110 /* XXX handle nbr change! */ 111 } 112 113 while (len >= sizeof(nbr_id)) { 114 memcpy(&nbr_id, buf, sizeof(nbr_id)); 115 if (nbr_id == iface->addr.s_addr) { 116 /* seen myself */ 117 if (nbr->state < NBR_STA_2_WAY) 118 nbr_fsm(nbr, NBR_EVT_2_WAY_RCVD); 119 break; 120 } 121 buf += sizeof(nbr_id); 122 len -= sizeof(nbr_id); 123 } 124 125 if (len == 0) { 126 nbr_fsm(nbr, NBR_EVT_1_WAY_RCVD); 127 return; 128 } 129 130 /* XXX len correct?? */ 131 132 return; 133 } 134