1 /* $OpenBSD: control.c,v 1.28 2020/01/01 10:09:34 denis 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 "ospf6d.h" 30 #include "ospf6.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 if (listen(control_state.fd, CONTROL_BACKLOG) == -1) { 114 log_warn("control_listen: listen"); 115 return (-1); 116 } 117 118 event_set(&control_state.ev, control_state.fd, EV_READ, 119 control_accept, NULL); 120 event_add(&control_state.ev, NULL); 121 evtimer_set(&control_state.evt, control_accept, NULL); 122 123 return (0); 124 } 125 126 void 127 control_cleanup(char *path) 128 { 129 if (path == NULL) 130 return; 131 event_del(&control_state.ev); 132 event_del(&control_state.evt); 133 unlink(path); 134 } 135 136 /* ARGSUSED */ 137 void 138 control_accept(int listenfd, short event, void *bula) 139 { 140 int connfd; 141 socklen_t len; 142 struct sockaddr_un sun; 143 struct ctl_conn *c; 144 145 event_add(&control_state.ev, NULL); 146 if ((event & EV_TIMEOUT)) 147 return; 148 149 len = sizeof(sun); 150 if ((connfd = accept4(listenfd, (struct sockaddr *)&sun, &len, 151 SOCK_CLOEXEC | SOCK_NONBLOCK)) == -1) { 152 /* 153 * Pause accept if we are out of file descriptors, or 154 * libevent will haunt us here too. 155 */ 156 if (errno == ENFILE || errno == EMFILE) { 157 struct timeval evtpause = { 1, 0 }; 158 159 event_del(&control_state.ev); 160 evtimer_add(&control_state.evt, &evtpause); 161 } else if (errno != EWOULDBLOCK && errno != EINTR && 162 errno != ECONNABORTED) 163 log_warn("control_accept: accept"); 164 return; 165 } 166 167 if ((c = calloc(1, sizeof(struct ctl_conn))) == NULL) { 168 log_warn("control_accept"); 169 close(connfd); 170 return; 171 } 172 173 imsg_init(&c->iev.ibuf, connfd); 174 c->iev.handler = control_dispatch_imsg; 175 c->iev.events = EV_READ; 176 event_set(&c->iev.ev, c->iev.ibuf.fd, c->iev.events, 177 c->iev.handler, &c->iev); 178 event_add(&c->iev.ev, NULL); 179 180 TAILQ_INSERT_TAIL(&ctl_conns, c, entry); 181 } 182 183 struct ctl_conn * 184 control_connbyfd(int fd) 185 { 186 struct ctl_conn *c; 187 188 TAILQ_FOREACH(c, &ctl_conns, entry) { 189 if (c->iev.ibuf.fd == fd) 190 break; 191 } 192 193 return (c); 194 } 195 196 struct ctl_conn * 197 control_connbypid(pid_t pid) 198 { 199 struct ctl_conn *c; 200 201 TAILQ_FOREACH(c, &ctl_conns, entry) { 202 if (c->iev.ibuf.pid == pid) 203 break; 204 } 205 206 return (c); 207 } 208 209 void 210 control_close(int fd) 211 { 212 struct ctl_conn *c; 213 214 if ((c = control_connbyfd(fd)) == NULL) { 215 log_warn("control_close: fd %d: not found", fd); 216 return; 217 } 218 219 msgbuf_clear(&c->iev.ibuf.w); 220 TAILQ_REMOVE(&ctl_conns, c, entry); 221 222 event_del(&c->iev.ev); 223 close(c->iev.ibuf.fd); 224 225 /* Some file descriptors are available again. */ 226 if (evtimer_pending(&control_state.evt, NULL)) { 227 evtimer_del(&control_state.evt); 228 event_add(&control_state.ev, NULL); 229 } 230 231 free(c); 232 } 233 234 /* ARGSUSED */ 235 void 236 control_dispatch_imsg(int fd, short event, void *bula) 237 { 238 struct ctl_conn *c; 239 struct imsg imsg; 240 ssize_t n; 241 unsigned int ifidx; 242 int verbose; 243 244 if ((c = control_connbyfd(fd)) == NULL) { 245 log_warn("control_dispatch_imsg: fd %d: not found", fd); 246 return; 247 } 248 249 if (event & EV_READ) { 250 if (((n = imsg_read(&c->iev.ibuf)) == -1 && errno != EAGAIN) || 251 n == 0) { 252 control_close(fd); 253 return; 254 } 255 } 256 if (event & EV_WRITE) { 257 if (msgbuf_write(&c->iev.ibuf.w) <= 0 && errno != EAGAIN) { 258 control_close(fd); 259 return; 260 } 261 } 262 263 for (;;) { 264 if ((n = imsg_get(&c->iev.ibuf, &imsg)) == -1) { 265 control_close(fd); 266 return; 267 } 268 269 if (n == 0) 270 break; 271 272 switch (imsg.hdr.type) { 273 case IMSG_CTL_FIB_COUPLE: 274 case IMSG_CTL_FIB_DECOUPLE: 275 ospfe_fib_update(imsg.hdr.type); 276 /* FALLTHROUGH */ 277 case IMSG_CTL_RELOAD: 278 c->iev.ibuf.pid = imsg.hdr.pid; 279 ospfe_imsg_compose_parent(imsg.hdr.type, 0, NULL, 0); 280 break; 281 case IMSG_CTL_KROUTE: 282 case IMSG_CTL_KROUTE_ADDR: 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_LINK: 299 case IMSG_CTL_SHOW_DB_NET: 300 case IMSG_CTL_SHOW_DB_RTR: 301 case IMSG_CTL_SHOW_DB_INTRA: 302 case IMSG_CTL_SHOW_DB_SELF: 303 case IMSG_CTL_SHOW_DB_SUM: 304 case IMSG_CTL_SHOW_DB_ASBR: 305 case IMSG_CTL_SHOW_RIB: 306 case IMSG_CTL_SHOW_SUM: 307 c->iev.ibuf.pid = imsg.hdr.pid; 308 ospfe_imsg_compose_rde(imsg.hdr.type, 0, imsg.hdr.pid, 309 imsg.data, imsg.hdr.len - IMSG_HEADER_SIZE); 310 break; 311 case IMSG_CTL_SHOW_NBR: 312 ospfe_nbr_ctl(c); 313 break; 314 case IMSG_CTL_LOG_VERBOSE: 315 if (imsg.hdr.len != IMSG_HEADER_SIZE + 316 sizeof(verbose)) 317 break; 318 319 /* forward to other processes */ 320 ospfe_imsg_compose_parent(imsg.hdr.type, imsg.hdr.pid, 321 imsg.data, imsg.hdr.len - IMSG_HEADER_SIZE); 322 ospfe_imsg_compose_rde(imsg.hdr.type, 0, imsg.hdr.pid, 323 imsg.data, imsg.hdr.len - IMSG_HEADER_SIZE); 324 325 memcpy(&verbose, imsg.data, sizeof(verbose)); 326 log_setverbose(verbose); 327 break; 328 default: 329 log_debug("control_dispatch_imsg: " 330 "error handling imsg %d", imsg.hdr.type); 331 break; 332 } 333 imsg_free(&imsg); 334 } 335 336 imsg_event_add(&c->iev); 337 } 338 339 int 340 control_imsg_relay(struct imsg *imsg) 341 { 342 struct ctl_conn *c; 343 344 if ((c = control_connbypid(imsg->hdr.pid)) == NULL) 345 return (0); 346 347 return (imsg_compose_event(&c->iev, imsg->hdr.type, 0, imsg->hdr.pid, 348 -1, imsg->data, imsg->hdr.len - IMSG_HEADER_SIZE)); 349 } 350