1 /* $OpenBSD: control.c,v 1.54 2024/11/21 13:38:14 claudio 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 TAILQ_HEAD(ctl_conns, ctl_conn) ctl_conns = TAILQ_HEAD_INITIALIZER(ctl_conns); 36 37 #define CONTROL_BACKLOG 5 38 39 struct ctl_conn *control_connbyfd(int); 40 struct ctl_conn *control_connbypid(pid_t); 41 void control_close(int); 42 43 struct { 44 struct event ev; 45 struct event evt; 46 int fd; 47 } control_state; 48 49 int 50 control_check(char *path) 51 { 52 struct sockaddr_un sun; 53 int fd; 54 55 bzero(&sun, sizeof(sun)); 56 sun.sun_family = AF_UNIX; 57 strlcpy(sun.sun_path, path, sizeof(sun.sun_path)); 58 59 if ((fd = socket(AF_UNIX, SOCK_STREAM, 0)) == -1) { 60 log_warn("control_check: socket check"); 61 return (-1); 62 } 63 64 if (connect(fd, (struct sockaddr *)&sun, sizeof(sun)) == 0) { 65 log_warnx("control_check: socket in use"); 66 close(fd); 67 return (-1); 68 } 69 70 close(fd); 71 72 return (0); 73 } 74 75 int 76 control_init(char *path) 77 { 78 struct sockaddr_un sun; 79 int fd; 80 mode_t old_umask; 81 82 if ((fd = socket(AF_UNIX, SOCK_STREAM | SOCK_CLOEXEC | SOCK_NONBLOCK, 83 0)) == -1) { 84 log_warn("control_init: socket"); 85 return (-1); 86 } 87 88 bzero(&sun, sizeof(sun)); 89 sun.sun_family = AF_UNIX; 90 strlcpy(sun.sun_path, path, sizeof(sun.sun_path)); 91 92 if (unlink(path) == -1) 93 if (errno != ENOENT) { 94 log_warn("control_init: unlink %s", path); 95 close(fd); 96 return (-1); 97 } 98 99 old_umask = umask(S_IXUSR|S_IXGRP|S_IWOTH|S_IROTH|S_IXOTH); 100 if (bind(fd, (struct sockaddr *)&sun, sizeof(sun)) == -1) { 101 log_warn("control_init: bind: %s", path); 102 close(fd); 103 umask(old_umask); 104 return (-1); 105 } 106 umask(old_umask); 107 108 if (chmod(path, S_IRUSR|S_IWUSR|S_IRGRP|S_IWGRP) == -1) { 109 log_warn("control_init: chmod"); 110 close(fd); 111 (void)unlink(path); 112 return (-1); 113 } 114 115 return (fd); 116 } 117 118 int 119 control_listen(int fd) 120 { 121 control_state.fd = fd; 122 123 if (listen(control_state.fd, CONTROL_BACKLOG) == -1) { 124 log_warn("control_listen: listen"); 125 return (-1); 126 } 127 128 event_set(&control_state.ev, control_state.fd, EV_READ, 129 control_accept, NULL); 130 event_add(&control_state.ev, NULL); 131 evtimer_set(&control_state.evt, control_accept, NULL); 132 133 return (0); 134 } 135 136 void 137 control_cleanup(void) 138 { 139 event_del(&control_state.ev); 140 event_del(&control_state.evt); 141 } 142 143 void 144 control_accept(int listenfd, short event, void *bula) 145 { 146 int connfd; 147 socklen_t len; 148 struct sockaddr_un sun; 149 struct ctl_conn *c; 150 151 event_add(&control_state.ev, NULL); 152 if ((event & EV_TIMEOUT)) 153 return; 154 155 len = sizeof(sun); 156 if ((connfd = accept4(listenfd, (struct sockaddr *)&sun, &len, 157 SOCK_CLOEXEC | SOCK_NONBLOCK)) == -1) { 158 /* 159 * Pause accept if we are out of file descriptors, or 160 * libevent will haunt us here too. 161 */ 162 if (errno == ENFILE || errno == EMFILE) { 163 struct timeval evtpause = { 1, 0 }; 164 165 event_del(&control_state.ev); 166 evtimer_add(&control_state.evt, &evtpause); 167 } else if (errno != EWOULDBLOCK && errno != EINTR && 168 errno != ECONNABORTED) 169 log_warn("control_accept: accept"); 170 return; 171 } 172 173 if ((c = calloc(1, sizeof(struct ctl_conn))) == NULL) { 174 log_warn("control_accept"); 175 close(connfd); 176 return; 177 } 178 179 if (imsgbuf_init(&c->iev.ibuf, connfd) == -1) { 180 log_warn("imsgbuf_init"); 181 close(connfd); 182 free(c); 183 return; 184 } 185 c->iev.handler = control_dispatch_imsg; 186 c->iev.events = EV_READ; 187 event_set(&c->iev.ev, c->iev.ibuf.fd, c->iev.events, 188 c->iev.handler, &c->iev); 189 event_add(&c->iev.ev, NULL); 190 191 TAILQ_INSERT_TAIL(&ctl_conns, c, entry); 192 } 193 194 struct ctl_conn * 195 control_connbyfd(int fd) 196 { 197 struct ctl_conn *c; 198 199 TAILQ_FOREACH(c, &ctl_conns, entry) { 200 if (c->iev.ibuf.fd == fd) 201 break; 202 } 203 204 return (c); 205 } 206 207 struct ctl_conn * 208 control_connbypid(pid_t pid) 209 { 210 struct ctl_conn *c; 211 212 TAILQ_FOREACH(c, &ctl_conns, entry) { 213 if (c->iev.ibuf.pid == pid) 214 break; 215 } 216 217 return (c); 218 } 219 220 void 221 control_close(int fd) 222 { 223 struct ctl_conn *c; 224 225 if ((c = control_connbyfd(fd)) == NULL) { 226 log_warn("control_close: fd %d: not found", fd); 227 return; 228 } 229 230 imsgbuf_clear(&c->iev.ibuf); 231 TAILQ_REMOVE(&ctl_conns, c, entry); 232 233 event_del(&c->iev.ev); 234 close(c->iev.ibuf.fd); 235 236 /* Some file descriptors are available again. */ 237 if (evtimer_pending(&control_state.evt, NULL)) { 238 evtimer_del(&control_state.evt); 239 event_add(&control_state.ev, NULL); 240 } 241 242 free(c); 243 } 244 245 void 246 control_dispatch_imsg(int fd, short event, void *bula) 247 { 248 struct ctl_conn *c; 249 struct imsg imsg; 250 ssize_t n; 251 unsigned int ifidx; 252 int verbose; 253 254 if ((c = control_connbyfd(fd)) == NULL) { 255 log_warn("control_dispatch_imsg: fd %d: not found", fd); 256 return; 257 } 258 259 if (event & EV_READ) { 260 if (imsgbuf_read(&c->iev.ibuf) != 1) { 261 control_close(fd); 262 return; 263 } 264 } 265 if (event & EV_WRITE) { 266 if (imsgbuf_write(&c->iev.ibuf) == -1) { 267 control_close(fd); 268 return; 269 } 270 } 271 272 for (;;) { 273 if ((n = imsg_get(&c->iev.ibuf, &imsg)) == -1) { 274 control_close(fd); 275 return; 276 } 277 278 if (n == 0) 279 break; 280 281 switch (imsg.hdr.type) { 282 case IMSG_CTL_FIB_COUPLE: 283 case IMSG_CTL_FIB_DECOUPLE: 284 ospfe_fib_update(imsg.hdr.type); 285 /* FALLTHROUGH */ 286 case IMSG_CTL_FIB_RELOAD: 287 case IMSG_CTL_RELOAD: 288 c->iev.ibuf.pid = imsg.hdr.pid; 289 ospfe_imsg_compose_parent(imsg.hdr.type, 0, NULL, 0); 290 break; 291 case IMSG_CTL_KROUTE: 292 case IMSG_CTL_KROUTE_ADDR: 293 case IMSG_CTL_IFINFO: 294 c->iev.ibuf.pid = imsg.hdr.pid; 295 ospfe_imsg_compose_parent(imsg.hdr.type, imsg.hdr.pid, 296 imsg.data, imsg.hdr.len - IMSG_HEADER_SIZE); 297 break; 298 case IMSG_CTL_SHOW_INTERFACE: 299 if (imsg.hdr.len == IMSG_HEADER_SIZE + 300 sizeof(ifidx)) { 301 memcpy(&ifidx, imsg.data, sizeof(ifidx)); 302 ospfe_iface_ctl(c, ifidx); 303 imsg_compose_event(&c->iev, IMSG_CTL_END, 0, 304 0, -1, NULL, 0); 305 } 306 break; 307 case IMSG_CTL_SHOW_DATABASE: 308 case IMSG_CTL_SHOW_DB_EXT: 309 case IMSG_CTL_SHOW_DB_NET: 310 case IMSG_CTL_SHOW_DB_RTR: 311 case IMSG_CTL_SHOW_DB_SELF: 312 case IMSG_CTL_SHOW_DB_SUM: 313 case IMSG_CTL_SHOW_DB_ASBR: 314 case IMSG_CTL_SHOW_DB_OPAQ: 315 case IMSG_CTL_SHOW_RIB: 316 case IMSG_CTL_SHOW_SUM: 317 c->iev.ibuf.pid = imsg.hdr.pid; 318 ospfe_imsg_compose_rde(imsg.hdr.type, 0, imsg.hdr.pid, 319 imsg.data, imsg.hdr.len - IMSG_HEADER_SIZE); 320 break; 321 case IMSG_CTL_SHOW_NBR: 322 ospfe_nbr_ctl(c); 323 break; 324 case IMSG_CTL_LOG_VERBOSE: 325 if (imsg.hdr.len != IMSG_HEADER_SIZE + 326 sizeof(verbose)) 327 break; 328 329 /* forward to other processes */ 330 ospfe_imsg_compose_parent(imsg.hdr.type, imsg.hdr.pid, 331 imsg.data, imsg.hdr.len - IMSG_HEADER_SIZE); 332 ospfe_imsg_compose_rde(imsg.hdr.type, 0, imsg.hdr.pid, 333 imsg.data, imsg.hdr.len - IMSG_HEADER_SIZE); 334 335 memcpy(&verbose, imsg.data, sizeof(verbose)); 336 log_setverbose(verbose); 337 break; 338 default: 339 log_debug("control_dispatch_imsg: " 340 "error handling imsg %d", imsg.hdr.type); 341 break; 342 } 343 imsg_free(&imsg); 344 } 345 346 imsg_event_add(&c->iev); 347 } 348 349 int 350 control_imsg_relay(struct imsg *imsg) 351 { 352 struct ctl_conn *c; 353 354 if ((c = control_connbypid(imsg->hdr.pid)) == NULL) 355 return (0); 356 357 return (imsg_compose_event(&c->iev, imsg->hdr.type, 0, imsg->hdr.pid, 358 -1, imsg->data, imsg->hdr.len - IMSG_HEADER_SIZE)); 359 } 360