1 /* 2 * sys-bsd.c - System-dependent procedures for setting up 3 * PPP interfaces on bsd-4.4-ish systems (including 386BSD, NetBSD, etc.) 4 * 5 * Copyright (c) 1989 Carnegie Mellon University. 6 * All rights reserved. 7 * 8 * Redistribution and use in source and binary forms are permitted 9 * provided that the above copyright notice and this paragraph are 10 * duplicated in all such forms and that any documentation, 11 * advertising materials, and other materials related to such 12 * distribution and use acknowledge that the software was developed 13 * by Carnegie Mellon University. The name of the 14 * University may not be used to endorse or promote products derived 15 * from this software without specific prior written permission. 16 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR 17 * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED 18 * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE. 19 * 20 * $FreeBSD$ 21 * 22 */ 23 24 /* 25 * TODO: 26 */ 27 28 #include <sys/param.h> 29 #include <sys/socket.h> 30 #include <net/if.h> 31 #include <net/route.h> 32 #include <net/if_dl.h> 33 #include <netinet/in.h> 34 #include <netinet/if_ether.h> 35 #include <arpa/inet.h> 36 #include <netinet/in_systm.h> 37 #include <netinet/ip.h> 38 #include <sys/un.h> 39 40 #include <errno.h> 41 #include <stdio.h> 42 #include <stdlib.h> 43 #include <string.h> 44 #include <sys/sysctl.h> 45 #include <termios.h> 46 #include <unistd.h> 47 48 #include "layer.h" 49 #include "mbuf.h" 50 #include "log.h" 51 #include "id.h" 52 #include "timer.h" 53 #include "fsm.h" 54 #include "defs.h" 55 #include "iplist.h" 56 #include "throughput.h" 57 #include "slcompress.h" 58 #include "lqr.h" 59 #include "hdlc.h" 60 #include "ipcp.h" 61 #include "filter.h" 62 #include "descriptor.h" 63 #include "lcp.h" 64 #include "ccp.h" 65 #include "link.h" 66 #include "mp.h" 67 #ifndef NORADIUS 68 #include "radius.h" 69 #endif 70 #include "bundle.h" 71 #include "iface.h" 72 #include "arp.h" 73 74 /* 75 * SET_SA_FAMILY - set the sa_family field of a struct sockaddr, 76 * if it exists. 77 */ 78 #define SET_SA_FAMILY(addr, family) \ 79 memset((char *) &(addr), '\0', sizeof(addr)); \ 80 addr.sa_family = (family); \ 81 addr.sa_len = sizeof(addr); 82 83 84 #if RTM_VERSION >= 3 85 86 /* 87 * arp_SetProxy - Make a proxy ARP entry for the peer. 88 */ 89 static struct { 90 struct rt_msghdr hdr; 91 struct sockaddr_inarp dst; 92 struct sockaddr_dl hwa; 93 char extra[128]; 94 } arpmsg; 95 96 static int 97 arp_ProxySub(struct bundle *bundle, struct in_addr addr, int add, int s) 98 { 99 int routes; 100 101 /* 102 * Get the hardware address of an interface on the same subnet as our local 103 * address. 104 */ 105 106 memset(&arpmsg, 0, sizeof arpmsg); 107 if (!get_ether_addr(s, addr, &arpmsg.hwa)) { 108 log_Printf(LogWARN, "%s: Cannot determine ethernet address for proxy ARP\n", 109 inet_ntoa(addr)); 110 return 0; 111 } 112 routes = ID0socket(PF_ROUTE, SOCK_RAW, AF_INET); 113 if (routes < 0) { 114 log_Printf(LogERROR, "arp_SetProxy: opening routing socket: %s\n", 115 strerror(errno)); 116 return 0; 117 } 118 arpmsg.hdr.rtm_type = add ? RTM_ADD : RTM_DELETE; 119 arpmsg.hdr.rtm_flags = RTF_ANNOUNCE | RTF_HOST | RTF_STATIC; 120 arpmsg.hdr.rtm_version = RTM_VERSION; 121 arpmsg.hdr.rtm_seq = ++bundle->routing_seq; 122 arpmsg.hdr.rtm_addrs = RTA_DST | RTA_GATEWAY; 123 arpmsg.hdr.rtm_inits = RTV_EXPIRE; 124 arpmsg.dst.sin_len = sizeof(struct sockaddr_inarp); 125 arpmsg.dst.sin_family = AF_INET; 126 arpmsg.dst.sin_addr.s_addr = addr.s_addr; 127 arpmsg.dst.sin_other = SIN_PROXY; 128 129 arpmsg.hdr.rtm_msglen = (char *) &arpmsg.hwa - (char *) &arpmsg 130 + arpmsg.hwa.sdl_len; 131 132 133 if (write(routes, &arpmsg, arpmsg.hdr.rtm_msglen) < 0 && 134 !(!add && errno == ESRCH)) { 135 log_Printf(LogERROR, "%s proxy arp entry %s: %s\n", 136 add ? "Add" : "Delete", inet_ntoa(addr), strerror(errno)); 137 close(routes); 138 return 0; 139 } 140 close(routes); 141 return 1; 142 } 143 144 int 145 arp_SetProxy(struct bundle *bundle, struct in_addr addr, int s) 146 { 147 148 return (arp_ProxySub(bundle, addr, 1, s)); 149 } 150 151 /* 152 * arp_ClearProxy - Delete the proxy ARP entry for the peer. 153 */ 154 int 155 arp_ClearProxy(struct bundle *bundle, struct in_addr addr, int s) 156 { 157 158 return (arp_ProxySub(bundle, addr, 0, s)); 159 } 160 161 #else /* RTM_VERSION */ 162 163 /* 164 * arp_SetProxy - Make a proxy ARP entry for the peer. 165 */ 166 int 167 arp_SetProxy(struct bundle *bundle, struct in_addr addr, int s) 168 { 169 struct arpreq arpreq; 170 struct { 171 struct sockaddr_dl sdl; 172 char space[128]; 173 } dls; 174 175 memset(&arpreq, '\0', sizeof arpreq); 176 177 /* 178 * Get the hardware address of an interface on the same subnet as our local 179 * address. 180 */ 181 if (!get_ether_addr(s, addr, &dls.sdl)) { 182 log_Printf(LOG_PHASE_BIT, "Cannot determine ethernet address for proxy ARP\n"); 183 return 0; 184 } 185 arpreq.arp_ha.sa_len = sizeof(struct sockaddr); 186 arpreq.arp_ha.sa_family = AF_UNSPEC; 187 memcpy(arpreq.arp_ha.sa_data, LLADDR(&dls.sdl), dls.sdl.sdl_alen); 188 SET_SA_FAMILY(arpreq.arp_pa, AF_INET); 189 ((struct sockaddr_in *)&arpreq.arp_pa)->sin_addr.s_addr = addr.s_addr; 190 arpreq.arp_flags = ATF_PERM | ATF_PUBL; 191 if (ID0ioctl(s, SIOCSARP, (caddr_t) & arpreq) < 0) { 192 log_Printf(LogERROR, "arp_SetProxy: ioctl(SIOCSARP): %s\n", 193 strerror(errno)); 194 return 0; 195 } 196 return 1; 197 } 198 199 /* 200 * arp_ClearProxy - Delete the proxy ARP entry for the peer. 201 */ 202 int 203 arp_ClearProxy(struct bundle *bundle, struct in_addr addr, int s) 204 { 205 struct arpreq arpreq; 206 207 memset(&arpreq, '\0', sizeof arpreq); 208 SET_SA_FAMILY(arpreq.arp_pa, AF_INET); 209 ((struct sockaddr_in *)&arpreq.arp_pa)->sin_addr.s_addr = addr.s_addr; 210 if (ID0ioctl(s, SIOCDARP, (caddr_t) & arpreq) < 0) { 211 log_Printf(LogERROR, "arp_ClearProxy: ioctl(SIOCDARP): %s\n", 212 strerror(errno)); 213 return 0; 214 } 215 return 1; 216 } 217 218 #endif /* RTM_VERSION */ 219 220 221 /* 222 * get_ether_addr - get the hardware address of an interface on the 223 * the same subnet as ipaddr. 224 */ 225 226 int 227 get_ether_addr(int s, struct in_addr ipaddr, struct sockaddr_dl *hwaddr) 228 { 229 int mib[6], skip; 230 size_t needed; 231 char *buf, *ptr, *end; 232 struct if_msghdr *ifm; 233 struct ifa_msghdr *ifam; 234 struct sockaddr_dl *dl; 235 struct sockaddr *sa[RTAX_MAX]; 236 237 mib[0] = CTL_NET; 238 mib[1] = PF_ROUTE; 239 mib[2] = 0; 240 mib[3] = 0; 241 mib[4] = NET_RT_IFLIST; 242 mib[5] = 0; 243 244 if (sysctl(mib, 6, NULL, &needed, NULL, 0) < 0) { 245 log_Printf(LogERROR, "get_ether_addr: sysctl: estimate: %s\n", 246 strerror(errno)); 247 return 0; 248 } 249 250 if ((buf = malloc(needed)) == NULL) 251 return 0; 252 253 if (sysctl(mib, 6, buf, &needed, NULL, 0) < 0) { 254 free(buf); 255 return 0; 256 } 257 end = buf + needed; 258 259 ptr = buf; 260 while (ptr < end) { 261 ifm = (struct if_msghdr *)ptr; /* On if_msghdr */ 262 if (ifm->ifm_type != RTM_IFINFO) 263 break; 264 dl = (struct sockaddr_dl *)(ifm + 1); /* Single _dl at end */ 265 skip = (ifm->ifm_flags & (IFF_UP | IFF_BROADCAST | IFF_POINTOPOINT | 266 IFF_NOARP | IFF_LOOPBACK)) != (IFF_UP | IFF_BROADCAST); 267 ptr += ifm->ifm_msglen; /* First ifa_msghdr */ 268 while (ptr < end) { 269 ifam = (struct ifa_msghdr *)ptr; /* Next ifa_msghdr (alias) */ 270 if (ifam->ifam_type != RTM_NEWADDR) /* finished ? */ 271 break; 272 ptr += ifam->ifam_msglen; 273 if (skip || (ifam->ifam_addrs & (RTA_NETMASK|RTA_IFA)) != 274 (RTA_NETMASK|RTA_IFA)) 275 continue; 276 /* Found a candidate. Do the addresses match ? */ 277 if (log_IsKept(LogDEBUG) && 278 ptr == (char *)ifm + ifm->ifm_msglen + ifam->ifam_msglen) 279 log_Printf(LogDEBUG, "%.*s interface is a candidate for proxy\n", 280 dl->sdl_nlen, dl->sdl_data); 281 282 iface_ParseHdr(ifam, sa); 283 284 if (sa[RTAX_IFA]->sa_family == AF_INET) { 285 struct sockaddr_in *ifa, *netmask; 286 287 ifa = (struct sockaddr_in *)sa[RTAX_IFA]; 288 netmask = (struct sockaddr_in *)sa[RTAX_NETMASK]; 289 290 if (log_IsKept(LogDEBUG)) { 291 char a[16]; 292 293 strncpy(a, inet_ntoa(netmask->sin_addr), sizeof a - 1); 294 a[sizeof a - 1] = '\0'; 295 log_Printf(LogDEBUG, "Check addr %s, mask %s\n", 296 inet_ntoa(ifa->sin_addr), a); 297 } 298 299 if ((ifa->sin_addr.s_addr & netmask->sin_addr.s_addr) == 300 (ipaddr.s_addr & netmask->sin_addr.s_addr)) { 301 log_Printf(LogPHASE, "Found interface %.*s for %s\n", 302 dl->sdl_alen, dl->sdl_data, inet_ntoa(ipaddr)); 303 memcpy(hwaddr, dl, dl->sdl_len); 304 free(buf); 305 return 1; 306 } 307 } 308 } 309 } 310 free(buf); 311 312 return 0; 313 } 314