1 /* $OpenBSD: control.c,v 1.7 2017/01/08 23:04:42 krw Exp $ */ 2 3 /* 4 * Copyright (c) 2003, 2004 Henning Brauer <henning@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/stat.h> 21 #include <sys/un.h> 22 23 #include <errno.h> 24 #include <stdlib.h> 25 #include <string.h> 26 #include <unistd.h> 27 28 #include "eigrpd.h" 29 #include "eigrpe.h" 30 #include "control.h" 31 #include "log.h" 32 33 #define CONTROL_BACKLOG 5 34 35 static void control_accept(int, short, void *); 36 static struct ctl_conn *control_connbyfd(int); 37 static struct ctl_conn *control_connbypid(pid_t); 38 static void control_close(int); 39 static void control_dispatch_imsg(int, short, void *); 40 41 int 42 control_init(char *path) 43 { 44 struct sockaddr_un sun; 45 int fd; 46 mode_t old_umask; 47 48 if ((fd = socket(AF_UNIX, SOCK_STREAM | SOCK_CLOEXEC | SOCK_NONBLOCK, 49 0)) == -1) { 50 log_warn("%s: socket", __func__); 51 return (-1); 52 } 53 54 memset(&sun, 0, sizeof(sun)); 55 sun.sun_family = AF_UNIX; 56 strlcpy(sun.sun_path, path, sizeof(sun.sun_path)); 57 58 if (unlink(path) == -1) 59 if (errno != ENOENT) { 60 log_warn("%s: unlink %s", __func__, path); 61 close(fd); 62 return (-1); 63 } 64 65 old_umask = umask(S_IXUSR|S_IXGRP|S_IWOTH|S_IROTH|S_IXOTH); 66 if (bind(fd, (struct sockaddr *)&sun, sizeof(sun)) == -1) { 67 log_warn("%s: bind: %s", __func__, path); 68 close(fd); 69 umask(old_umask); 70 return (-1); 71 } 72 umask(old_umask); 73 74 if (chmod(path, S_IRUSR|S_IWUSR|S_IRGRP|S_IWGRP) == -1) { 75 log_warn("%s: chmod", __func__); 76 close(fd); 77 (void)unlink(path); 78 return (-1); 79 } 80 81 control_state.fd = fd; 82 83 return (0); 84 } 85 86 int 87 control_listen(void) 88 { 89 90 if (listen(control_state.fd, CONTROL_BACKLOG) == -1) { 91 log_warn("%s: listen", __func__); 92 return (-1); 93 } 94 95 event_set(&control_state.ev, control_state.fd, EV_READ, 96 control_accept, NULL); 97 event_add(&control_state.ev, NULL); 98 evtimer_set(&control_state.evt, control_accept, NULL); 99 100 return (0); 101 } 102 103 void 104 control_cleanup(char *path) 105 { 106 if (path == NULL) 107 return; 108 event_del(&control_state.ev); 109 event_del(&control_state.evt); 110 unlink(path); 111 } 112 113 /* ARGSUSED */ 114 static void 115 control_accept(int listenfd, short event, void *bula) 116 { 117 int connfd; 118 socklen_t len; 119 struct sockaddr_un sun; 120 struct ctl_conn *c; 121 122 event_add(&control_state.ev, NULL); 123 if ((event & EV_TIMEOUT)) 124 return; 125 126 len = sizeof(sun); 127 if ((connfd = accept4(listenfd, (struct sockaddr *)&sun, &len, 128 SOCK_CLOEXEC | SOCK_NONBLOCK)) == -1) { 129 /* 130 * Pause accept if we are out of file descriptors, or 131 * libevent will haunt us here too. 132 */ 133 if (errno == ENFILE || errno == EMFILE) { 134 struct timeval evtpause = { 1, 0 }; 135 136 event_del(&control_state.ev); 137 evtimer_add(&control_state.evt, &evtpause); 138 } else if (errno != EWOULDBLOCK && errno != EINTR && 139 errno != ECONNABORTED) 140 log_warn("%s: accept4", __func__); 141 return; 142 } 143 144 if ((c = calloc(1, sizeof(struct ctl_conn))) == NULL) { 145 log_warn("%s: calloc", __func__); 146 close(connfd); 147 return; 148 } 149 150 imsg_init(&c->iev.ibuf, connfd); 151 c->iev.handler = control_dispatch_imsg; 152 c->iev.events = EV_READ; 153 event_set(&c->iev.ev, c->iev.ibuf.fd, c->iev.events, 154 c->iev.handler, &c->iev); 155 event_add(&c->iev.ev, NULL); 156 157 TAILQ_INSERT_TAIL(&ctl_conns, c, entry); 158 } 159 160 static struct ctl_conn * 161 control_connbyfd(int fd) 162 { 163 struct ctl_conn *c; 164 165 TAILQ_FOREACH(c, &ctl_conns, entry) { 166 if (c->iev.ibuf.fd == fd) 167 break; 168 } 169 170 return (c); 171 } 172 173 static struct ctl_conn * 174 control_connbypid(pid_t pid) 175 { 176 struct ctl_conn *c; 177 178 TAILQ_FOREACH(c, &ctl_conns, entry) { 179 if (c->iev.ibuf.pid == pid) 180 break; 181 } 182 183 return (c); 184 } 185 186 static void 187 control_close(int fd) 188 { 189 struct ctl_conn *c; 190 191 if ((c = control_connbyfd(fd)) == NULL) { 192 log_warnx("%s: fd %d: not found", __func__, fd); 193 return; 194 } 195 196 msgbuf_clear(&c->iev.ibuf.w); 197 TAILQ_REMOVE(&ctl_conns, c, entry); 198 199 event_del(&c->iev.ev); 200 close(c->iev.ibuf.fd); 201 202 /* Some file descriptors are available again. */ 203 if (evtimer_pending(&control_state.evt, NULL)) { 204 evtimer_del(&control_state.evt); 205 event_add(&control_state.ev, NULL); 206 } 207 208 free(c); 209 } 210 211 /* ARGSUSED */ 212 static void 213 control_dispatch_imsg(int fd, short event, void *bula) 214 { 215 struct ctl_conn *c; 216 struct imsg imsg; 217 ssize_t n; 218 unsigned int ifidx; 219 int verbose; 220 221 if ((c = control_connbyfd(fd)) == NULL) { 222 log_warnx("%s: fd %d: not found", __func__, fd); 223 return; 224 } 225 226 if (event & EV_READ) { 227 if (((n = imsg_read(&c->iev.ibuf)) == -1 && errno != EAGAIN) || 228 n == 0) { 229 control_close(fd); 230 return; 231 } 232 } 233 if (event & EV_WRITE) { 234 if (msgbuf_write(&c->iev.ibuf.w) <= 0 && errno != EAGAIN) { 235 control_close(fd); 236 return; 237 } 238 } 239 240 for (;;) { 241 if ((n = imsg_get(&c->iev.ibuf, &imsg)) == -1) { 242 control_close(fd); 243 return; 244 } 245 246 if (n == 0) 247 break; 248 249 switch (imsg.hdr.type) { 250 case IMSG_CTL_FIB_COUPLE: 251 case IMSG_CTL_FIB_DECOUPLE: 252 case IMSG_CTL_RELOAD: 253 c->iev.ibuf.pid = imsg.hdr.pid; 254 eigrpe_imsg_compose_parent(imsg.hdr.type, 0, NULL, 0); 255 break; 256 case IMSG_CTL_KROUTE: 257 case IMSG_CTL_IFINFO: 258 c->iev.ibuf.pid = imsg.hdr.pid; 259 eigrpe_imsg_compose_parent(imsg.hdr.type, imsg.hdr.pid, 260 imsg.data, imsg.hdr.len - IMSG_HEADER_SIZE); 261 break; 262 case IMSG_CTL_SHOW_INTERFACE: 263 if (imsg.hdr.len != IMSG_HEADER_SIZE + 264 sizeof(ifidx)) 265 break; 266 267 memcpy(&ifidx, imsg.data, sizeof(ifidx)); 268 eigrpe_iface_ctl(c, ifidx); 269 imsg_compose_event(&c->iev, IMSG_CTL_END, 0, 270 0, -1, NULL, 0); 271 break; 272 case IMSG_CTL_SHOW_TOPOLOGY: 273 if (imsg.hdr.len != IMSG_HEADER_SIZE + 274 sizeof(struct ctl_show_topology_req)) 275 break; 276 277 c->iev.ibuf.pid = imsg.hdr.pid; 278 eigrpe_imsg_compose_rde(imsg.hdr.type, 0, imsg.hdr.pid, 279 imsg.data, imsg.hdr.len - IMSG_HEADER_SIZE); 280 break; 281 case IMSG_CTL_SHOW_NBR: 282 eigrpe_nbr_ctl(c); 283 break; 284 case IMSG_CTL_SHOW_STATS: 285 eigrpe_stats_ctl(c); 286 break; 287 case IMSG_CTL_CLEAR_NBR: 288 if (imsg.hdr.len != IMSG_HEADER_SIZE + 289 sizeof(struct ctl_nbr)) 290 break; 291 292 nbr_clear_ctl(imsg.data); 293 break; 294 case IMSG_CTL_LOG_VERBOSE: 295 if (imsg.hdr.len != IMSG_HEADER_SIZE + 296 sizeof(verbose)) 297 break; 298 299 /* forward to other processes */ 300 eigrpe_imsg_compose_parent(imsg.hdr.type, imsg.hdr.pid, 301 imsg.data, imsg.hdr.len - IMSG_HEADER_SIZE); 302 eigrpe_imsg_compose_rde(imsg.hdr.type, 0, imsg.hdr.pid, 303 imsg.data, imsg.hdr.len - IMSG_HEADER_SIZE); 304 305 memcpy(&verbose, imsg.data, sizeof(verbose)); 306 log_verbose(verbose); 307 break; 308 default: 309 log_debug("%s: error handling imsg %d", __func__, 310 imsg.hdr.type); 311 break; 312 } 313 imsg_free(&imsg); 314 } 315 316 imsg_event_add(&c->iev); 317 } 318 319 int 320 control_imsg_relay(struct imsg *imsg) 321 { 322 struct ctl_conn *c; 323 324 if ((c = control_connbypid(imsg->hdr.pid)) == NULL) 325 return (0); 326 327 return (imsg_compose_event(&c->iev, imsg->hdr.type, 0, imsg->hdr.pid, 328 -1, imsg->data, imsg->hdr.len - IMSG_HEADER_SIZE)); 329 } 330