1 /* $OpenBSD: control.c,v 1.29 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 "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(void) 128 { 129 event_del(&control_state.ev); 130 event_del(&control_state.evt); 131 } 132 133 /* ARGSUSED */ 134 void 135 control_accept(int listenfd, short event, void *bula) 136 { 137 int connfd; 138 socklen_t len; 139 struct sockaddr_un sun; 140 struct ctl_conn *c; 141 142 event_add(&control_state.ev, NULL); 143 if ((event & EV_TIMEOUT)) 144 return; 145 146 len = sizeof(sun); 147 if ((connfd = accept4(listenfd, (struct sockaddr *)&sun, &len, 148 SOCK_CLOEXEC | SOCK_NONBLOCK)) == -1) { 149 /* 150 * Pause accept if we are out of file descriptors, or 151 * libevent will haunt us here too. 152 */ 153 if (errno == ENFILE || errno == EMFILE) { 154 struct timeval evtpause = { 1, 0 }; 155 156 event_del(&control_state.ev); 157 evtimer_add(&control_state.evt, &evtpause); 158 } else if (errno != EWOULDBLOCK && errno != EINTR && 159 errno != ECONNABORTED) 160 log_warn("control_accept: accept"); 161 return; 162 } 163 164 if ((c = calloc(1, sizeof(struct ctl_conn))) == NULL) { 165 log_warn("control_accept"); 166 close(connfd); 167 return; 168 } 169 170 imsg_init(&c->iev.ibuf, connfd); 171 c->iev.handler = control_dispatch_imsg; 172 c->iev.events = EV_READ; 173 event_set(&c->iev.ev, c->iev.ibuf.fd, c->iev.events, 174 c->iev.handler, &c->iev); 175 event_add(&c->iev.ev, NULL); 176 177 TAILQ_INSERT_TAIL(&ctl_conns, c, entry); 178 } 179 180 struct ctl_conn * 181 control_connbyfd(int fd) 182 { 183 struct ctl_conn *c; 184 185 TAILQ_FOREACH(c, &ctl_conns, entry) { 186 if (c->iev.ibuf.fd == fd) 187 break; 188 } 189 190 return (c); 191 } 192 193 struct ctl_conn * 194 control_connbypid(pid_t pid) 195 { 196 struct ctl_conn *c; 197 198 TAILQ_FOREACH(c, &ctl_conns, entry) { 199 if (c->iev.ibuf.pid == pid) 200 break; 201 } 202 203 return (c); 204 } 205 206 void 207 control_close(int fd) 208 { 209 struct ctl_conn *c; 210 211 if ((c = control_connbyfd(fd)) == NULL) { 212 log_warn("control_close: fd %d: not found", fd); 213 return; 214 } 215 216 msgbuf_clear(&c->iev.ibuf.w); 217 TAILQ_REMOVE(&ctl_conns, c, entry); 218 219 event_del(&c->iev.ev); 220 close(c->iev.ibuf.fd); 221 222 /* Some file descriptors are available again. */ 223 if (evtimer_pending(&control_state.evt, NULL)) { 224 evtimer_del(&control_state.evt); 225 event_add(&control_state.ev, NULL); 226 } 227 228 free(c); 229 } 230 231 /* ARGSUSED */ 232 void 233 control_dispatch_imsg(int fd, short event, void *bula) 234 { 235 struct ctl_conn *c; 236 struct imsg imsg; 237 ssize_t n; 238 unsigned int ifidx; 239 int verbose; 240 241 if ((c = control_connbyfd(fd)) == NULL) { 242 log_warn("control_dispatch_imsg: fd %d: not found", fd); 243 return; 244 } 245 246 if (event & EV_READ) { 247 if (((n = imsg_read(&c->iev.ibuf)) == -1 && errno != EAGAIN) || 248 n == 0) { 249 control_close(fd); 250 return; 251 } 252 } 253 if (event & EV_WRITE) { 254 if (msgbuf_write(&c->iev.ibuf.w) <= 0 && errno != EAGAIN) { 255 control_close(fd); 256 return; 257 } 258 } 259 260 for (;;) { 261 if ((n = imsg_get(&c->iev.ibuf, &imsg)) == -1) { 262 control_close(fd); 263 return; 264 } 265 266 if (n == 0) 267 break; 268 269 switch (imsg.hdr.type) { 270 case IMSG_CTL_FIB_COUPLE: 271 case IMSG_CTL_FIB_DECOUPLE: 272 ospfe_fib_update(imsg.hdr.type); 273 /* FALLTHROUGH */ 274 case IMSG_CTL_RELOAD: 275 c->iev.ibuf.pid = imsg.hdr.pid; 276 ospfe_imsg_compose_parent(imsg.hdr.type, 0, NULL, 0); 277 break; 278 case IMSG_CTL_KROUTE: 279 case IMSG_CTL_KROUTE_ADDR: 280 c->iev.ibuf.pid = imsg.hdr.pid; 281 ospfe_imsg_compose_parent(imsg.hdr.type, imsg.hdr.pid, 282 imsg.data, imsg.hdr.len - IMSG_HEADER_SIZE); 283 break; 284 case IMSG_CTL_SHOW_INTERFACE: 285 if (imsg.hdr.len == IMSG_HEADER_SIZE + 286 sizeof(ifidx)) { 287 memcpy(&ifidx, imsg.data, sizeof(ifidx)); 288 ospfe_iface_ctl(c, ifidx); 289 imsg_compose_event(&c->iev, IMSG_CTL_END, 0, 290 0, -1, NULL, 0); 291 } 292 break; 293 case IMSG_CTL_SHOW_DATABASE: 294 case IMSG_CTL_SHOW_DB_EXT: 295 case IMSG_CTL_SHOW_DB_LINK: 296 case IMSG_CTL_SHOW_DB_NET: 297 case IMSG_CTL_SHOW_DB_RTR: 298 case IMSG_CTL_SHOW_DB_INTRA: 299 case IMSG_CTL_SHOW_DB_SELF: 300 case IMSG_CTL_SHOW_DB_SUM: 301 case IMSG_CTL_SHOW_DB_ASBR: 302 case IMSG_CTL_SHOW_RIB: 303 case IMSG_CTL_SHOW_SUM: 304 c->iev.ibuf.pid = imsg.hdr.pid; 305 ospfe_imsg_compose_rde(imsg.hdr.type, 0, imsg.hdr.pid, 306 imsg.data, imsg.hdr.len - IMSG_HEADER_SIZE); 307 break; 308 case IMSG_CTL_SHOW_NBR: 309 ospfe_nbr_ctl(c); 310 break; 311 case IMSG_CTL_LOG_VERBOSE: 312 if (imsg.hdr.len != IMSG_HEADER_SIZE + 313 sizeof(verbose)) 314 break; 315 316 /* forward to other processes */ 317 ospfe_imsg_compose_parent(imsg.hdr.type, imsg.hdr.pid, 318 imsg.data, imsg.hdr.len - IMSG_HEADER_SIZE); 319 ospfe_imsg_compose_rde(imsg.hdr.type, 0, imsg.hdr.pid, 320 imsg.data, imsg.hdr.len - IMSG_HEADER_SIZE); 321 322 memcpy(&verbose, imsg.data, sizeof(verbose)); 323 log_setverbose(verbose); 324 break; 325 default: 326 log_debug("control_dispatch_imsg: " 327 "error handling imsg %d", imsg.hdr.type); 328 break; 329 } 330 imsg_free(&imsg); 331 } 332 333 imsg_event_add(&c->iev); 334 } 335 336 int 337 control_imsg_relay(struct imsg *imsg) 338 { 339 struct ctl_conn *c; 340 341 if ((c = control_connbypid(imsg->hdr.pid)) == NULL) 342 return (0); 343 344 return (imsg_compose_event(&c->iev, imsg->hdr.type, 0, imsg->hdr.pid, 345 -1, imsg->data, imsg->hdr.len - IMSG_HEADER_SIZE)); 346 } 347