1 /* $OpenBSD: control.c,v 1.30 2021/01/19 09:42:11 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 "ospf6d.h" 30 #include "ospf6.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 /* ARGSUSED */ 144 void 145 control_accept(int listenfd, short event, void *bula) 146 { 147 int connfd; 148 socklen_t len; 149 struct sockaddr_un sun; 150 struct ctl_conn *c; 151 152 event_add(&control_state.ev, NULL); 153 if ((event & EV_TIMEOUT)) 154 return; 155 156 len = sizeof(sun); 157 if ((connfd = accept4(listenfd, (struct sockaddr *)&sun, &len, 158 SOCK_CLOEXEC | SOCK_NONBLOCK)) == -1) { 159 /* 160 * Pause accept if we are out of file descriptors, or 161 * libevent will haunt us here too. 162 */ 163 if (errno == ENFILE || errno == EMFILE) { 164 struct timeval evtpause = { 1, 0 }; 165 166 event_del(&control_state.ev); 167 evtimer_add(&control_state.evt, &evtpause); 168 } else if (errno != EWOULDBLOCK && errno != EINTR && 169 errno != ECONNABORTED) 170 log_warn("control_accept: accept"); 171 return; 172 } 173 174 if ((c = calloc(1, sizeof(struct ctl_conn))) == NULL) { 175 log_warn("control_accept"); 176 close(connfd); 177 return; 178 } 179 180 imsg_init(&c->iev.ibuf, connfd); 181 c->iev.handler = control_dispatch_imsg; 182 c->iev.events = EV_READ; 183 event_set(&c->iev.ev, c->iev.ibuf.fd, c->iev.events, 184 c->iev.handler, &c->iev); 185 event_add(&c->iev.ev, NULL); 186 187 TAILQ_INSERT_TAIL(&ctl_conns, c, entry); 188 } 189 190 struct ctl_conn * 191 control_connbyfd(int fd) 192 { 193 struct ctl_conn *c; 194 195 TAILQ_FOREACH(c, &ctl_conns, entry) { 196 if (c->iev.ibuf.fd == fd) 197 break; 198 } 199 200 return (c); 201 } 202 203 struct ctl_conn * 204 control_connbypid(pid_t pid) 205 { 206 struct ctl_conn *c; 207 208 TAILQ_FOREACH(c, &ctl_conns, entry) { 209 if (c->iev.ibuf.pid == pid) 210 break; 211 } 212 213 return (c); 214 } 215 216 void 217 control_close(int fd) 218 { 219 struct ctl_conn *c; 220 221 if ((c = control_connbyfd(fd)) == NULL) { 222 log_warn("control_close: fd %d: not found", fd); 223 return; 224 } 225 226 msgbuf_clear(&c->iev.ibuf.w); 227 TAILQ_REMOVE(&ctl_conns, c, entry); 228 229 event_del(&c->iev.ev); 230 close(c->iev.ibuf.fd); 231 232 /* Some file descriptors are available again. */ 233 if (evtimer_pending(&control_state.evt, NULL)) { 234 evtimer_del(&control_state.evt); 235 event_add(&control_state.ev, NULL); 236 } 237 238 free(c); 239 } 240 241 /* ARGSUSED */ 242 void 243 control_dispatch_imsg(int fd, short event, void *bula) 244 { 245 struct ctl_conn *c; 246 struct imsg imsg; 247 ssize_t n; 248 unsigned int ifidx; 249 int verbose; 250 251 if ((c = control_connbyfd(fd)) == NULL) { 252 log_warn("control_dispatch_imsg: fd %d: not found", fd); 253 return; 254 } 255 256 if (event & EV_READ) { 257 if (((n = imsg_read(&c->iev.ibuf)) == -1 && errno != EAGAIN) || 258 n == 0) { 259 control_close(fd); 260 return; 261 } 262 } 263 if (event & EV_WRITE) { 264 if (msgbuf_write(&c->iev.ibuf.w) <= 0 && errno != EAGAIN) { 265 control_close(fd); 266 return; 267 } 268 } 269 270 for (;;) { 271 if ((n = imsg_get(&c->iev.ibuf, &imsg)) == -1) { 272 control_close(fd); 273 return; 274 } 275 276 if (n == 0) 277 break; 278 279 switch (imsg.hdr.type) { 280 case IMSG_CTL_FIB_COUPLE: 281 case IMSG_CTL_FIB_DECOUPLE: 282 ospfe_fib_update(imsg.hdr.type); 283 /* FALLTHROUGH */ 284 case IMSG_CTL_RELOAD: 285 c->iev.ibuf.pid = imsg.hdr.pid; 286 ospfe_imsg_compose_parent(imsg.hdr.type, 0, NULL, 0); 287 break; 288 case IMSG_CTL_KROUTE: 289 case IMSG_CTL_KROUTE_ADDR: 290 c->iev.ibuf.pid = imsg.hdr.pid; 291 ospfe_imsg_compose_parent(imsg.hdr.type, imsg.hdr.pid, 292 imsg.data, imsg.hdr.len - IMSG_HEADER_SIZE); 293 break; 294 case IMSG_CTL_SHOW_INTERFACE: 295 if (imsg.hdr.len == IMSG_HEADER_SIZE + 296 sizeof(ifidx)) { 297 memcpy(&ifidx, imsg.data, sizeof(ifidx)); 298 ospfe_iface_ctl(c, ifidx); 299 imsg_compose_event(&c->iev, IMSG_CTL_END, 0, 300 0, -1, NULL, 0); 301 } 302 break; 303 case IMSG_CTL_SHOW_DATABASE: 304 case IMSG_CTL_SHOW_DB_EXT: 305 case IMSG_CTL_SHOW_DB_LINK: 306 case IMSG_CTL_SHOW_DB_NET: 307 case IMSG_CTL_SHOW_DB_RTR: 308 case IMSG_CTL_SHOW_DB_INTRA: 309 case IMSG_CTL_SHOW_DB_SELF: 310 case IMSG_CTL_SHOW_DB_SUM: 311 case IMSG_CTL_SHOW_DB_ASBR: 312 case IMSG_CTL_SHOW_RIB: 313 case IMSG_CTL_SHOW_SUM: 314 c->iev.ibuf.pid = imsg.hdr.pid; 315 ospfe_imsg_compose_rde(imsg.hdr.type, 0, imsg.hdr.pid, 316 imsg.data, imsg.hdr.len - IMSG_HEADER_SIZE); 317 break; 318 case IMSG_CTL_SHOW_NBR: 319 ospfe_nbr_ctl(c); 320 break; 321 case IMSG_CTL_LOG_VERBOSE: 322 if (imsg.hdr.len != IMSG_HEADER_SIZE + 323 sizeof(verbose)) 324 break; 325 326 /* forward to other processes */ 327 ospfe_imsg_compose_parent(imsg.hdr.type, imsg.hdr.pid, 328 imsg.data, imsg.hdr.len - IMSG_HEADER_SIZE); 329 ospfe_imsg_compose_rde(imsg.hdr.type, 0, imsg.hdr.pid, 330 imsg.data, imsg.hdr.len - IMSG_HEADER_SIZE); 331 332 memcpy(&verbose, imsg.data, sizeof(verbose)); 333 log_setverbose(verbose); 334 break; 335 default: 336 log_debug("control_dispatch_imsg: " 337 "error handling imsg %d", imsg.hdr.type); 338 break; 339 } 340 imsg_free(&imsg); 341 } 342 343 imsg_event_add(&c->iev); 344 } 345 346 int 347 control_imsg_relay(struct imsg *imsg) 348 { 349 struct ctl_conn *c; 350 351 if ((c = control_connbypid(imsg->hdr.pid)) == NULL) 352 return (0); 353 354 return (imsg_compose_event(&c->iev, imsg->hdr.type, 0, imsg->hdr.pid, 355 -1, imsg->data, imsg->hdr.len - IMSG_HEADER_SIZE)); 356 } 357