1 /* $OpenBSD: control.c,v 1.46 2020/09/16 20:50:10 remi 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/socket.h> 22 #include <sys/un.h> 23 #include <errno.h> 24 #include <fcntl.h> 25 #include <stdlib.h> 26 #include <string.h> 27 #include <unistd.h> 28 29 #include "ospfd.h" 30 #include "ospf.h" 31 #include "ospfe.h" 32 #include "log.h" 33 #include "control.h" 34 35 #define CONTROL_BACKLOG 5 36 37 struct ctl_conn *control_connbyfd(int); 38 struct ctl_conn *control_connbypid(pid_t); 39 void control_close(int); 40 41 int 42 control_check(char *path) 43 { 44 struct sockaddr_un sun; 45 int fd; 46 47 bzero(&sun, sizeof(sun)); 48 sun.sun_family = AF_UNIX; 49 strlcpy(sun.sun_path, path, sizeof(sun.sun_path)); 50 51 if ((fd = socket(AF_UNIX, SOCK_STREAM, 0)) == -1) { 52 log_warn("control_check: socket check"); 53 return (-1); 54 } 55 56 if (connect(fd, (struct sockaddr *)&sun, sizeof(sun)) == 0) { 57 log_warnx("control_check: socket in use"); 58 close(fd); 59 return (-1); 60 } 61 62 close(fd); 63 64 return (0); 65 } 66 67 int 68 control_init(char *path) 69 { 70 struct sockaddr_un sun; 71 int fd; 72 mode_t old_umask; 73 74 if ((fd = socket(AF_UNIX, SOCK_STREAM | SOCK_CLOEXEC | SOCK_NONBLOCK, 75 0)) == -1) { 76 log_warn("control_init: socket"); 77 return (-1); 78 } 79 80 bzero(&sun, sizeof(sun)); 81 sun.sun_family = AF_UNIX; 82 strlcpy(sun.sun_path, path, sizeof(sun.sun_path)); 83 84 if (unlink(path) == -1) 85 if (errno != ENOENT) { 86 log_warn("control_init: unlink %s", path); 87 close(fd); 88 return (-1); 89 } 90 91 old_umask = umask(S_IXUSR|S_IXGRP|S_IWOTH|S_IROTH|S_IXOTH); 92 if (bind(fd, (struct sockaddr *)&sun, sizeof(sun)) == -1) { 93 log_warn("control_init: bind: %s", path); 94 close(fd); 95 umask(old_umask); 96 return (-1); 97 } 98 umask(old_umask); 99 100 if (chmod(path, S_IRUSR|S_IWUSR|S_IRGRP|S_IWGRP) == -1) { 101 log_warn("control_init: chmod"); 102 close(fd); 103 (void)unlink(path); 104 return (-1); 105 } 106 107 return (fd); 108 } 109 110 int 111 control_listen(void) 112 { 113 114 if (listen(control_state.fd, CONTROL_BACKLOG) == -1) { 115 log_warn("control_listen: listen"); 116 return (-1); 117 } 118 119 event_set(&control_state.ev, control_state.fd, EV_READ, 120 control_accept, NULL); 121 event_add(&control_state.ev, NULL); 122 evtimer_set(&control_state.evt, control_accept, NULL); 123 124 return (0); 125 } 126 127 void 128 control_cleanup(void) 129 { 130 event_del(&control_state.ev); 131 event_del(&control_state.evt); 132 } 133 134 /* ARGSUSED */ 135 void 136 control_accept(int listenfd, short event, void *bula) 137 { 138 int connfd; 139 socklen_t len; 140 struct sockaddr_un sun; 141 struct ctl_conn *c; 142 143 event_add(&control_state.ev, NULL); 144 if ((event & EV_TIMEOUT)) 145 return; 146 147 len = sizeof(sun); 148 if ((connfd = accept4(listenfd, (struct sockaddr *)&sun, &len, 149 SOCK_CLOEXEC | SOCK_NONBLOCK)) == -1) { 150 /* 151 * Pause accept if we are out of file descriptors, or 152 * libevent will haunt us here too. 153 */ 154 if (errno == ENFILE || errno == EMFILE) { 155 struct timeval evtpause = { 1, 0 }; 156 157 event_del(&control_state.ev); 158 evtimer_add(&control_state.evt, &evtpause); 159 } else if (errno != EWOULDBLOCK && errno != EINTR && 160 errno != ECONNABORTED) 161 log_warn("control_accept: accept"); 162 return; 163 } 164 165 if ((c = calloc(1, sizeof(struct ctl_conn))) == NULL) { 166 log_warn("control_accept"); 167 close(connfd); 168 return; 169 } 170 171 imsg_init(&c->iev.ibuf, connfd); 172 c->iev.handler = control_dispatch_imsg; 173 c->iev.events = EV_READ; 174 event_set(&c->iev.ev, c->iev.ibuf.fd, c->iev.events, 175 c->iev.handler, &c->iev); 176 event_add(&c->iev.ev, NULL); 177 178 TAILQ_INSERT_TAIL(&ctl_conns, c, entry); 179 } 180 181 struct ctl_conn * 182 control_connbyfd(int fd) 183 { 184 struct ctl_conn *c; 185 186 TAILQ_FOREACH(c, &ctl_conns, entry) { 187 if (c->iev.ibuf.fd == fd) 188 break; 189 } 190 191 return (c); 192 } 193 194 struct ctl_conn * 195 control_connbypid(pid_t pid) 196 { 197 struct ctl_conn *c; 198 199 TAILQ_FOREACH(c, &ctl_conns, entry) { 200 if (c->iev.ibuf.pid == pid) 201 break; 202 } 203 204 return (c); 205 } 206 207 void 208 control_close(int fd) 209 { 210 struct ctl_conn *c; 211 212 if ((c = control_connbyfd(fd)) == NULL) { 213 log_warn("control_close: fd %d: not found", fd); 214 return; 215 } 216 217 msgbuf_clear(&c->iev.ibuf.w); 218 TAILQ_REMOVE(&ctl_conns, c, entry); 219 220 event_del(&c->iev.ev); 221 close(c->iev.ibuf.fd); 222 223 /* Some file descriptors are available again. */ 224 if (evtimer_pending(&control_state.evt, NULL)) { 225 evtimer_del(&control_state.evt); 226 event_add(&control_state.ev, NULL); 227 } 228 229 free(c); 230 } 231 232 /* ARGSUSED */ 233 void 234 control_dispatch_imsg(int fd, short event, void *bula) 235 { 236 struct ctl_conn *c; 237 struct imsg imsg; 238 ssize_t n; 239 unsigned int ifidx; 240 int verbose; 241 242 if ((c = control_connbyfd(fd)) == NULL) { 243 log_warn("control_dispatch_imsg: fd %d: not found", fd); 244 return; 245 } 246 247 if (event & EV_READ) { 248 if (((n = imsg_read(&c->iev.ibuf)) == -1 && errno != EAGAIN) || 249 n == 0) { 250 control_close(fd); 251 return; 252 } 253 } 254 if (event & EV_WRITE) { 255 if (msgbuf_write(&c->iev.ibuf.w) <= 0 && errno != EAGAIN) { 256 control_close(fd); 257 return; 258 } 259 } 260 261 for (;;) { 262 if ((n = imsg_get(&c->iev.ibuf, &imsg)) == -1) { 263 control_close(fd); 264 return; 265 } 266 267 if (n == 0) 268 break; 269 270 switch (imsg.hdr.type) { 271 case IMSG_CTL_FIB_COUPLE: 272 case IMSG_CTL_FIB_DECOUPLE: 273 ospfe_fib_update(imsg.hdr.type); 274 /* FALLTHROUGH */ 275 case IMSG_CTL_FIB_RELOAD: 276 case IMSG_CTL_RELOAD: 277 c->iev.ibuf.pid = imsg.hdr.pid; 278 ospfe_imsg_compose_parent(imsg.hdr.type, 0, NULL, 0); 279 break; 280 case IMSG_CTL_KROUTE: 281 case IMSG_CTL_KROUTE_ADDR: 282 case IMSG_CTL_IFINFO: 283 c->iev.ibuf.pid = imsg.hdr.pid; 284 ospfe_imsg_compose_parent(imsg.hdr.type, imsg.hdr.pid, 285 imsg.data, imsg.hdr.len - IMSG_HEADER_SIZE); 286 break; 287 case IMSG_CTL_SHOW_INTERFACE: 288 if (imsg.hdr.len == IMSG_HEADER_SIZE + 289 sizeof(ifidx)) { 290 memcpy(&ifidx, imsg.data, sizeof(ifidx)); 291 ospfe_iface_ctl(c, ifidx); 292 imsg_compose_event(&c->iev, IMSG_CTL_END, 0, 293 0, -1, NULL, 0); 294 } 295 break; 296 case IMSG_CTL_SHOW_DATABASE: 297 case IMSG_CTL_SHOW_DB_EXT: 298 case IMSG_CTL_SHOW_DB_NET: 299 case IMSG_CTL_SHOW_DB_RTR: 300 case IMSG_CTL_SHOW_DB_SELF: 301 case IMSG_CTL_SHOW_DB_SUM: 302 case IMSG_CTL_SHOW_DB_ASBR: 303 case IMSG_CTL_SHOW_DB_OPAQ: 304 case IMSG_CTL_SHOW_RIB: 305 case IMSG_CTL_SHOW_SUM: 306 c->iev.ibuf.pid = imsg.hdr.pid; 307 ospfe_imsg_compose_rde(imsg.hdr.type, 0, imsg.hdr.pid, 308 imsg.data, imsg.hdr.len - IMSG_HEADER_SIZE); 309 break; 310 case IMSG_CTL_SHOW_NBR: 311 ospfe_nbr_ctl(c); 312 break; 313 case IMSG_CTL_LOG_VERBOSE: 314 if (imsg.hdr.len != IMSG_HEADER_SIZE + 315 sizeof(verbose)) 316 break; 317 318 /* forward to other processes */ 319 ospfe_imsg_compose_parent(imsg.hdr.type, imsg.hdr.pid, 320 imsg.data, imsg.hdr.len - IMSG_HEADER_SIZE); 321 ospfe_imsg_compose_rde(imsg.hdr.type, 0, imsg.hdr.pid, 322 imsg.data, imsg.hdr.len - IMSG_HEADER_SIZE); 323 324 memcpy(&verbose, imsg.data, sizeof(verbose)); 325 log_setverbose(verbose); 326 break; 327 default: 328 log_debug("control_dispatch_imsg: " 329 "error handling imsg %d", imsg.hdr.type); 330 break; 331 } 332 imsg_free(&imsg); 333 } 334 335 imsg_event_add(&c->iev); 336 } 337 338 int 339 control_imsg_relay(struct imsg *imsg) 340 { 341 struct ctl_conn *c; 342 343 if ((c = control_connbypid(imsg->hdr.pid)) == NULL) 344 return (0); 345 346 return (imsg_compose_event(&c->iev, imsg->hdr.type, 0, imsg->hdr.pid, 347 -1, imsg->data, imsg->hdr.len - IMSG_HEADER_SIZE)); 348 } 349