1 /* $OpenBSD: control.c,v 1.16 2012/04/11 08:34:41 deraadt 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 "igmp.h" 30 #include "dvmrpd.h" 31 #include "dvmrp.h" 32 #include "dvmrpe.h" 33 #include "log.h" 34 #include "control.h" 35 36 #define CONTROL_BACKLOG 5 37 38 struct ctl_conn *control_connbyfd(int); 39 struct ctl_conn *control_connbypid(pid_t); 40 void control_close(int); 41 42 int 43 control_init(void) 44 { 45 struct sockaddr_un sun; 46 int fd; 47 mode_t old_umask; 48 49 if ((fd = socket(AF_UNIX, SOCK_STREAM, 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, DVMRPD_SOCKET, sizeof(sun.sun_path)); 57 58 if (unlink(DVMRPD_SOCKET) == -1) 59 if (errno != ENOENT) { 60 log_warn("control_init: unlink %s", DVMRPD_SOCKET); 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", DVMRPD_SOCKET); 68 close(fd); 69 umask(old_umask); 70 return (-1); 71 } 72 umask(old_umask); 73 74 if (chmod(DVMRPD_SOCKET, S_IRUSR|S_IWUSR|S_IRGRP|S_IWGRP) == -1) { 75 log_warn("control_init: chmod"); 76 close(fd); 77 (void)unlink(DVMRPD_SOCKET); 78 return (-1); 79 } 80 81 session_socket_blockmode(fd, BM_NONBLOCK); 82 control_state.fd = fd; 83 84 return (0); 85 } 86 87 int 88 control_listen(void) 89 { 90 91 if (listen(control_state.fd, CONTROL_BACKLOG) == -1) { 92 log_warn("control_listen: listen"); 93 return (-1); 94 } 95 96 event_set(&control_state.ev, control_state.fd, EV_READ, 97 control_accept, NULL); 98 event_add(&control_state.ev, NULL); 99 evtimer_set(&control_state.evt, control_accept, NULL); 100 101 return (0); 102 } 103 104 void 105 control_cleanup(void) 106 { 107 event_del(&control_state.ev); 108 event_del(&control_state.evt); 109 unlink(DVMRPD_SOCKET); 110 } 111 112 /* ARGSUSED */ 113 void 114 control_accept(int listenfd, short event, void *bula) 115 { 116 int connfd; 117 socklen_t len; 118 struct sockaddr_un sun; 119 struct ctl_conn *c; 120 121 event_add(&control_state.ev, NULL); 122 if ((event & EV_TIMEOUT)) 123 return; 124 125 len = sizeof(sun); 126 if ((connfd = accept(listenfd, 127 (struct sockaddr *)&sun, &len)) == -1) { 128 /* 129 * Pause accept if we are out of file descriptors, or 130 * libevent will haunt us here too. 131 */ 132 if (errno == ENFILE || errno == EMFILE) { 133 struct timeval evtpause = { 1, 0 }; 134 135 event_del(&control_state.ev); 136 evtimer_add(&control_state.evt, &evtpause); 137 } else if (errno != EWOULDBLOCK && errno != EINTR) 138 log_warn("control_accept: accept"); 139 return; 140 } 141 142 session_socket_blockmode(connfd, BM_NONBLOCK); 143 144 if ((c = calloc(1, sizeof(struct ctl_conn))) == NULL) { 145 log_warn("control_accept"); 146 close(connfd); 147 return; 148 } 149 150 imsg_init(&c->iev.ibuf, connfd); 151 c->iev.handler = control_dispatch_imsg; 152 c->iev.events = EV_READ; 153 event_set(&c->iev.ev, c->iev.ibuf.fd, c->iev.events, 154 c->iev.handler, &c->iev); 155 event_add(&c->iev.ev, NULL); 156 157 TAILQ_INSERT_TAIL(&ctl_conns, c, entry); 158 } 159 160 struct ctl_conn * 161 control_connbyfd(int fd) 162 { 163 struct ctl_conn *c; 164 165 for (c = TAILQ_FIRST(&ctl_conns); c != NULL && c->iev.ibuf.fd != fd; 166 c = TAILQ_NEXT(c, entry)) 167 ; /* nothing */ 168 169 return (c); 170 } 171 172 struct ctl_conn * 173 control_connbypid(pid_t pid) 174 { 175 struct ctl_conn *c; 176 177 for (c = TAILQ_FIRST(&ctl_conns); c != NULL && c->iev.ibuf.pid != pid; 178 c = TAILQ_NEXT(c, entry)) 179 ; /* nothing */ 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 int 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 || n == 0) { 226 control_close(fd); 227 return; 228 } 229 } 230 if (event & EV_WRITE) { 231 if (msgbuf_write(&c->iev.ibuf.w) == -1) { 232 control_close(fd); 233 return; 234 } 235 } 236 237 for (;;) { 238 if ((n = imsg_get(&c->iev.ibuf, &imsg)) == -1) { 239 control_close(fd); 240 return; 241 } 242 243 if (n == 0) 244 break; 245 246 switch (imsg.hdr.type) { 247 case IMSG_CTL_MFC_COUPLE: 248 case IMSG_CTL_MFC_DECOUPLE: 249 case IMSG_CTL_RELOAD: 250 dvmrpe_imsg_compose_parent(imsg.hdr.type, 0, NULL, 0); 251 break; 252 case IMSG_CTL_SHOW_IFACE: 253 if (imsg.hdr.len == IMSG_HEADER_SIZE + 254 sizeof(ifidx)) { 255 memcpy(&ifidx, imsg.data, sizeof(ifidx)); 256 dvmrpe_iface_ctl(c, ifidx); 257 imsg_compose_event(&c->iev, IMSG_CTL_END, 0, 258 0, -1, NULL, 0); 259 } 260 break; 261 case IMSG_CTL_SHOW_IGMP: 262 if (imsg.hdr.len == IMSG_HEADER_SIZE + 263 sizeof(ifidx)) { 264 memcpy(&ifidx, imsg.data, sizeof(ifidx)); 265 dvmrpe_iface_igmp_ctl(c, ifidx); 266 imsg_compose_event(&c->iev, IMSG_CTL_END, 0, 267 0, -1, NULL, 0); 268 } 269 break; 270 case IMSG_CTL_SHOW_NBR: 271 dvmrpe_nbr_ctl(c); 272 break; 273 case IMSG_CTL_SHOW_RIB: 274 case IMSG_CTL_SHOW_MFC: 275 case IMSG_CTL_SHOW_SUM: 276 c->iev.ibuf.pid = imsg.hdr.pid; 277 dvmrpe_imsg_compose_rde(imsg.hdr.type, 0, imsg.hdr.pid, 278 imsg.data, imsg.hdr.len - IMSG_HEADER_SIZE); 279 break; 280 case IMSG_CTL_LOG_VERBOSE: 281 if (imsg.hdr.len != IMSG_HEADER_SIZE + 282 sizeof(verbose)) 283 break; 284 285 /* forward to other processes */ 286 dvmrpe_imsg_compose_parent(imsg.hdr.type, imsg.hdr.pid, 287 imsg.data, imsg.hdr.len - IMSG_HEADER_SIZE); 288 dvmrpe_imsg_compose_rde(imsg.hdr.type, 0, imsg.hdr.pid, 289 imsg.data, imsg.hdr.len - IMSG_HEADER_SIZE); 290 291 memcpy(&verbose, imsg.data, sizeof(verbose)); 292 log_verbose(verbose); 293 break; 294 default: 295 log_debug("control_dispatch_imsg: " 296 "error handling imsg %d", imsg.hdr.type); 297 break; 298 } 299 imsg_free(&imsg); 300 } 301 302 imsg_event_add(&c->iev); 303 } 304 305 int 306 control_imsg_relay(struct imsg *imsg) 307 { 308 struct ctl_conn *c; 309 310 if ((c = control_connbypid(imsg->hdr.pid)) == NULL) 311 return (0); 312 313 return (imsg_compose_event(&c->iev, imsg->hdr.type, 0, imsg->hdr.pid, 314 -1, imsg->data, imsg->hdr.len - IMSG_HEADER_SIZE)); 315 } 316 317 void 318 session_socket_blockmode(int fd, enum blockmodes bm) 319 { 320 int flags; 321 322 if ((flags = fcntl(fd, F_GETFL, 0)) == -1) 323 fatal("fcntl F_GETFL"); 324 325 if (bm == BM_NONBLOCK) 326 flags |= O_NONBLOCK; 327 else 328 flags &= ~O_NONBLOCK; 329 330 if ((flags = fcntl(fd, F_SETFL, flags)) == -1) 331 fatal("fcntl F_SETFL"); 332 } 333