1 /* $OpenBSD: control.c,v 1.25 2017/01/17 22:10:56 krw 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 "ripd.h" 30 #include "rip.h" 31 #include "ripe.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_init(char *path) 43 { 44 struct sockaddr_un sun; 45 int fd; 46 mode_t old_umask; 47 48 if ((fd = socket(AF_UNIX, SOCK_STREAM | SOCK_CLOEXEC | SOCK_NONBLOCK, 49 0)) == -1) { 50 log_warn("control_init: socket"); 51 return (-1); 52 } 53 54 bzero(&sun, sizeof(sun)); 55 sun.sun_family = AF_UNIX; 56 strlcpy(sun.sun_path, path, sizeof(sun.sun_path)); 57 58 if (unlink(path) == -1) 59 if (errno != ENOENT) { 60 log_warn("control_init: unlink %s", path); 61 close(fd); 62 return (-1); 63 } 64 65 old_umask = umask(S_IXUSR|S_IXGRP|S_IWOTH|S_IROTH|S_IXOTH); 66 if (bind(fd, (struct sockaddr *)&sun, sizeof(sun)) == -1) { 67 log_warn("control_init: bind: %s", path); 68 close(fd); 69 umask(old_umask); 70 return (-1); 71 } 72 umask(old_umask); 73 74 if (chmod(path, S_IRUSR|S_IWUSR|S_IRGRP|S_IWGRP) == -1) { 75 log_warn("control_init: chmod"); 76 close(fd); 77 (void)unlink(path); 78 return (-1); 79 } 80 81 control_state.fd = fd; 82 83 return (0); 84 } 85 86 int 87 control_listen(void) 88 { 89 90 if (listen(control_state.fd, CONTROL_BACKLOG) == -1) { 91 log_warn("control_listen: listen"); 92 return (-1); 93 } 94 95 event_set(&control_state.ev, control_state.fd, EV_READ, 96 control_accept, NULL); 97 event_add(&control_state.ev, NULL); 98 evtimer_set(&control_state.evt, control_accept, NULL); 99 100 return (0); 101 } 102 103 void 104 control_cleanup(char *path) 105 { 106 event_del(&control_state.ev); 107 event_del(&control_state.evt); 108 unlink(path); 109 } 110 111 /* ARGSUSED */ 112 void 113 control_accept(int listenfd, short event, void *bula) 114 { 115 int connfd; 116 socklen_t len; 117 struct sockaddr_un sun; 118 struct ctl_conn *c; 119 120 event_add(&control_state.ev, NULL); 121 if ((event & EV_TIMEOUT)) 122 return; 123 124 len = sizeof(sun); 125 if ((connfd = accept4(listenfd, (struct sockaddr *)&sun, &len, 126 SOCK_CLOEXEC | SOCK_NONBLOCK)) == -1) { 127 /* 128 * Pause accept if we are out of file descriptors, or 129 * libevent will haunt us here too. 130 */ 131 if (errno == ENFILE || errno == EMFILE) { 132 struct timeval evtpause = { 1, 0 }; 133 134 event_del(&control_state.ev); 135 evtimer_add(&control_state.evt, &evtpause); 136 } else if (errno != EWOULDBLOCK && errno != EINTR && 137 errno != ECONNABORTED) 138 log_warn("control_accept: accept"); 139 return; 140 } 141 142 if ((c = calloc(1, sizeof(struct ctl_conn))) == NULL) { 143 log_warn("control_accept"); 144 close(connfd); 145 return; 146 } 147 148 imsg_init(&c->iev.ibuf, connfd); 149 c->iev.handler = control_dispatch_imsg; 150 c->iev.events = EV_READ; 151 event_set(&c->iev.ev, c->iev.ibuf.fd, c->iev.events, 152 c->iev.handler, &c->iev); 153 event_add(&c->iev.ev, NULL); 154 155 TAILQ_INSERT_TAIL(&ctl_conns, c, entry); 156 } 157 158 struct ctl_conn * 159 control_connbyfd(int fd) 160 { 161 struct ctl_conn *c; 162 163 TAILQ_FOREACH(c, &ctl_conns, entry) { 164 if (c->iev.ibuf.fd == fd) 165 break; 166 } 167 168 return (c); 169 } 170 171 struct ctl_conn * 172 control_connbypid(pid_t pid) 173 { 174 struct ctl_conn *c; 175 176 TAILQ_FOREACH(c, &ctl_conns, entry) { 177 if (c->iev.ibuf.pid == pid) 178 break; 179 } 180 181 return (c); 182 } 183 184 void 185 control_close(int fd) 186 { 187 struct ctl_conn *c; 188 189 if ((c = control_connbyfd(fd)) == NULL) { 190 log_warn("control_close: fd %d: not found", fd); 191 return; 192 } 193 194 msgbuf_clear(&c->iev.ibuf.w); 195 TAILQ_REMOVE(&ctl_conns, c, entry); 196 197 event_del(&c->iev.ev); 198 close(c->iev.ibuf.fd); 199 200 /* Some file descriptors are available again. */ 201 if (evtimer_pending(&control_state.evt, NULL)) { 202 evtimer_del(&control_state.evt); 203 event_add(&control_state.ev, NULL); 204 } 205 206 free(c); 207 } 208 209 /* ARGSUSED */ 210 void 211 control_dispatch_imsg(int fd, short event, void *bula) 212 { 213 struct ctl_conn *c; 214 struct imsg imsg; 215 ssize_t n; 216 unsigned int ifidx; 217 int verbose; 218 219 if ((c = control_connbyfd(fd)) == NULL) { 220 log_warn("control_dispatch_imsg: fd %d: not found", fd); 221 return; 222 } 223 224 if (event & EV_READ) { 225 if (((n = imsg_read(&c->iev.ibuf)) == -1 && errno != EAGAIN) || 226 n == 0) { 227 control_close(fd); 228 return; 229 } 230 } 231 if (event & EV_WRITE) { 232 if (msgbuf_write(&c->iev.ibuf.w) <= 0 && errno != EAGAIN) { 233 control_close(fd); 234 return; 235 } 236 } 237 238 for (;;) { 239 if ((n = imsg_get(&c->iev.ibuf, &imsg)) == -1) { 240 control_close(fd); 241 return; 242 } 243 244 if (n == 0) 245 break; 246 247 switch (imsg.hdr.type) { 248 case IMSG_CTL_SHOW_INTERFACE: 249 if (imsg.hdr.len - IMSG_HEADER_SIZE != sizeof(ifidx)) 250 return; 251 252 memcpy(&ifidx, imsg.data, sizeof(ifidx)); 253 ripe_iface_ctl(c, ifidx); 254 imsg_compose(&c->iev.ibuf, IMSG_CTL_END, 0, 0, 255 -1, NULL, 0); 256 257 break; 258 case IMSG_CTL_SHOW_RIB: 259 c->iev.ibuf.pid = imsg.hdr.pid; 260 ripe_imsg_compose_rde(imsg.hdr.type, 0, 261 imsg.hdr.pid, imsg.data, imsg.hdr.len - 262 IMSG_HEADER_SIZE); 263 break; 264 case IMSG_CTL_SHOW_NBR: 265 ripe_nbr_ctl(c); 266 break; 267 case IMSG_CTL_KROUTE_ADDR: 268 case IMSG_CTL_KROUTE: 269 case IMSG_CTL_IFINFO: 270 c->iev.ibuf.pid = imsg.hdr.pid; 271 ripe_imsg_compose_parent(imsg.hdr.type, 272 imsg.hdr.pid, imsg.data, 273 imsg.hdr.len - IMSG_HEADER_SIZE); 274 break; 275 case IMSG_CTL_FIB_COUPLE: 276 case IMSG_CTL_FIB_DECOUPLE: 277 case IMSG_CTL_RELOAD: 278 c->iev.ibuf.pid = imsg.hdr.pid; 279 ripe_imsg_compose_parent(imsg.hdr.type, 0, NULL, 0); 280 break; 281 case IMSG_CTL_LOG_VERBOSE: 282 if (imsg.hdr.len != IMSG_HEADER_SIZE + 283 sizeof(verbose)) 284 break; 285 286 /* forward to other processes */ 287 ripe_imsg_compose_parent(imsg.hdr.type, imsg.hdr.pid, 288 imsg.data, imsg.hdr.len - IMSG_HEADER_SIZE); 289 ripe_imsg_compose_rde(imsg.hdr.type, 0, imsg.hdr.pid, 290 imsg.data, imsg.hdr.len - IMSG_HEADER_SIZE); 291 292 memcpy(&verbose, imsg.data, sizeof(verbose)); 293 log_verbose(verbose); 294 break; 295 default: 296 log_debug("control_dispatch_imsg: " 297 "error handling imsg %d", imsg.hdr.type); 298 break; 299 } 300 imsg_free(&imsg); 301 } 302 303 imsg_event_add(&c->iev); 304 } 305 306 int 307 control_imsg_relay(struct imsg *imsg) 308 { 309 struct ctl_conn *c; 310 311 if ((c = control_connbypid(imsg->hdr.pid)) == NULL) 312 return (0); 313 314 return (imsg_compose_event(&c->iev, imsg->hdr.type, 0, imsg->hdr.pid, 315 -1, imsg->data, imsg->hdr.len - IMSG_HEADER_SIZE)); 316 } 317