1 /* $OpenBSD: carp.c,v 1.17 2019/01/22 09:25:29 krw Exp $ */ 2 3 /* 4 * Copyright (c) 2005 H�kan Olsson. 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 * 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 18 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 19 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 21 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 22 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 23 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 24 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 25 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 26 */ 27 28 /* 29 * This code was written under funding by Multicom Security AB. 30 */ 31 32 33 #include <sys/types.h> 34 #include <sys/ioctl.h> 35 #include <sys/select.h> 36 #include <sys/socket.h> 37 #include <net/if.h> 38 #include <net/route.h> 39 40 #include <errno.h> 41 #include <stdio.h> 42 #include <string.h> 43 #include <unistd.h> 44 45 #include "monitor.h" 46 #include "sasyncd.h" 47 48 int carp_demoted = 0; 49 50 /* Map CARP interface link state into RUNSTATE enum */ 51 static enum RUNSTATE 52 carp_map_state(u_char link_state) 53 { 54 enum RUNSTATE state = FAIL; 55 56 switch(link_state) { 57 case LINK_STATE_UP: 58 case LINK_STATE_HALF_DUPLEX: 59 case LINK_STATE_FULL_DUPLEX: 60 state = MASTER; 61 break; 62 case LINK_STATE_DOWN: 63 state = SLAVE; 64 break; 65 case LINK_STATE_UNKNOWN: 66 case LINK_STATE_INVALID: 67 state = INIT; 68 break; 69 } 70 71 return state; 72 } 73 74 static enum RUNSTATE 75 carp_get_state(char *ifname) 76 { 77 struct ifreq ifr; 78 struct if_data ifrdat; 79 int s, saved_errno; 80 81 if (!ifname || !*ifname) { 82 errno = ENOENT; 83 return FAIL; 84 } 85 86 memset(&ifr, 0, sizeof ifr); 87 strlcpy(ifr.ifr_name, ifname, sizeof ifr.ifr_name); 88 89 s = socket(AF_INET, SOCK_DGRAM, 0); 90 if (s < 0) 91 return FAIL; 92 93 ifr.ifr_data = (caddr_t)&ifrdat; 94 if (ioctl(s, SIOCGIFDATA, (caddr_t)&ifr) == -1) { 95 saved_errno = errno; 96 close(s); 97 errno = saved_errno; 98 return FAIL; 99 } 100 close(s); 101 return carp_map_state(ifrdat.ifi_link_state); 102 } 103 104 void 105 carp_demote(int demote, int force) 106 { 107 struct ifgroupreq ifgr; 108 int s; 109 110 if (carp_demoted + demote < 0) { 111 log_msg(1, "carp_demote: mismatched promotion"); 112 return; 113 } 114 115 s = socket(AF_INET, SOCK_DGRAM, 0); 116 if (s < 0) { 117 log_msg(1, "carp_demote: couldn't open socket"); 118 return; 119 } 120 121 bzero(&ifgr, sizeof(ifgr)); 122 strlcpy(ifgr.ifgr_name, cfgstate.carp_ifgroup, sizeof(ifgr.ifgr_name)); 123 124 /* Unless we force it, don't demote if we're not demoting already. */ 125 if (!force) { 126 if (ioctl(s, SIOCGIFGATTR, (caddr_t)&ifgr) == -1) { 127 log_msg(1, "carp_demote: unable to get " 128 "the demote state of group '%s'", 129 cfgstate.carp_ifgroup); 130 goto done; 131 } 132 133 if (ifgr.ifgr_attrib.ifg_carp_demoted == 0) 134 goto done; 135 } 136 137 ifgr.ifgr_attrib.ifg_carp_demoted = demote; 138 if (ioctl(s, SIOCSIFGATTR, (caddr_t)&ifgr) == -1) 139 log_msg(1, "carp_demote: unable to %s the demote state " 140 "of group '%s'", (demote > 0) ? 141 "increment" : "decrement", cfgstate.carp_ifgroup); 142 else { 143 carp_demoted += demote; 144 log_msg(1, "carp_demote: %sed the demote state " 145 "of group '%s'", (demote > 0) ? 146 "increment" : "decrement", cfgstate.carp_ifgroup); 147 } 148 done: 149 close(s); 150 } 151 152 const char* 153 carp_state_name(enum RUNSTATE state) 154 { 155 static const char *carpstate[] = CARPSTATES; 156 157 if ((unsigned)state > FAIL) 158 state = FAIL; 159 return carpstate[state]; 160 } 161 162 void 163 carp_update_state(enum RUNSTATE current_state) 164 { 165 166 if ((unsigned)current_state > FAIL) { 167 log_err("carp_update_state: invalid carp state, abort"); 168 cfgstate.runstate = FAIL; 169 return; 170 } 171 172 if (current_state != cfgstate.runstate) { 173 log_msg(1, "carp_update_state: switching state to %s", 174 carp_state_name(current_state)); 175 cfgstate.runstate = current_state; 176 if (current_state == MASTER) 177 pfkey_set_promisc(); 178 control_setrun(); 179 net_ctl_update_state(); 180 } 181 } 182 183 void 184 carp_check_state() 185 { 186 carp_update_state(carp_get_state(cfgstate.carp_ifname)); 187 } 188 189 void 190 carp_set_rfd(fd_set *fds) 191 { 192 if (cfgstate.route_socket != -1) 193 FD_SET(cfgstate.route_socket, fds); 194 } 195 196 static void 197 carp_read(void) 198 { 199 char msg[2048]; 200 struct rt_msghdr *rtm = (struct rt_msghdr *)&msg; 201 struct if_msghdr ifm; 202 ssize_t len; 203 204 len = read(cfgstate.route_socket, msg, sizeof(msg)); 205 206 if (len < (ssize_t)sizeof(struct rt_msghdr) || 207 rtm->rtm_version != RTM_VERSION || 208 rtm->rtm_type != RTM_IFINFO) 209 return; 210 211 memcpy(&ifm, rtm, sizeof(ifm)); 212 213 if (ifm.ifm_index == cfgstate.carp_ifindex) 214 carp_update_state(carp_map_state(ifm.ifm_data.ifi_link_state)); 215 } 216 217 void 218 carp_read_message(fd_set *fds) 219 { 220 if (cfgstate.route_socket != -1) 221 if (FD_ISSET(cfgstate.route_socket, fds)) 222 (void)carp_read(); 223 } 224 225 /* Initialize the CARP state. */ 226 int 227 carp_init(void) 228 { 229 unsigned int rtfilter; 230 231 cfgstate.route_socket = -1; 232 if (cfgstate.lockedstate != INIT) { 233 cfgstate.runstate = cfgstate.lockedstate; 234 log_msg(1, "carp_init: locking runstate to %s", 235 carp_state_name(cfgstate.runstate)); 236 return 0; 237 } 238 239 if (!cfgstate.carp_ifname || !*cfgstate.carp_ifname) { 240 fprintf(stderr, "No carp interface\n"); 241 return -1; 242 } 243 244 cfgstate.carp_ifindex = if_nametoindex(cfgstate.carp_ifname); 245 if (!cfgstate.carp_ifindex) { 246 fprintf(stderr, "No carp interface index\n"); 247 return -1; 248 } 249 250 cfgstate.route_socket = socket(AF_ROUTE, SOCK_RAW, 0); 251 if (cfgstate.route_socket < 0) { 252 fprintf(stderr, "No routing socket\n"); 253 return -1; 254 } 255 256 rtfilter = ROUTE_FILTER(RTM_IFINFO); 257 if (setsockopt(cfgstate.route_socket, AF_ROUTE, ROUTE_MSGFILTER, 258 &rtfilter, sizeof(rtfilter)) == -1) /* not fatal */ 259 log_msg(2, "carp_init: setsockopt"); 260 261 cfgstate.runstate = carp_get_state(cfgstate.carp_ifname); 262 if (cfgstate.runstate == FAIL) { 263 fprintf(stderr, "Failed to check interface \"%s\".\n", 264 cfgstate.carp_ifname); 265 fprintf(stderr, "Correct or manually select runstate.\n"); 266 return -1; 267 } 268 log_msg(1, "carp_init: initializing runstate to %s", 269 carp_state_name(cfgstate.runstate)); 270 271 return 0; 272 } 273 274 /* Enable or disable isakmpd/iked connection checker. */ 275 void 276 control_setrun(void) 277 { 278 if (cfgstate.runstate == MASTER) { 279 if (monitor_control_active(1)) 280 log_msg(0, "failed to activate controlled daemon"); 281 } else { 282 if (monitor_control_active(0)) 283 log_msg(0, "failed to passivate controlled daemon"); 284 } 285 } 286