1 /* $OpenBSD: control.c,v 1.8 2018/08/05 08:10:35 mestre 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/un.h> 22 23 #include <errno.h> 24 #include <stdlib.h> 25 #include <string.h> 26 #include <unistd.h> 27 28 #include "eigrpd.h" 29 #include "eigrpe.h" 30 #include "control.h" 31 #include "log.h" 32 33 #define CONTROL_BACKLOG 5 34 35 static void control_accept(int, short, void *); 36 static struct ctl_conn *control_connbyfd(int); 37 static struct ctl_conn *control_connbypid(pid_t); 38 static void control_close(int); 39 static void control_dispatch_imsg(int, short, void *); 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("%s: socket", __func__); 51 return (-1); 52 } 53 54 memset(&sun, 0, 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("%s: unlink %s", __func__, 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("%s: bind: %s", __func__, 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("%s: chmod", __func__); 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("%s: listen", __func__); 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 /* ARGSUSED */ 104 static void 105 control_accept(int listenfd, short event, void *bula) 106 { 107 int connfd; 108 socklen_t len; 109 struct sockaddr_un sun; 110 struct ctl_conn *c; 111 112 event_add(&control_state.ev, NULL); 113 if ((event & EV_TIMEOUT)) 114 return; 115 116 len = sizeof(sun); 117 if ((connfd = accept4(listenfd, (struct sockaddr *)&sun, &len, 118 SOCK_CLOEXEC | SOCK_NONBLOCK)) == -1) { 119 /* 120 * Pause accept if we are out of file descriptors, or 121 * libevent will haunt us here too. 122 */ 123 if (errno == ENFILE || errno == EMFILE) { 124 struct timeval evtpause = { 1, 0 }; 125 126 event_del(&control_state.ev); 127 evtimer_add(&control_state.evt, &evtpause); 128 } else if (errno != EWOULDBLOCK && errno != EINTR && 129 errno != ECONNABORTED) 130 log_warn("%s: accept4", __func__); 131 return; 132 } 133 134 if ((c = calloc(1, sizeof(struct ctl_conn))) == NULL) { 135 log_warn("%s: calloc", __func__); 136 close(connfd); 137 return; 138 } 139 140 imsg_init(&c->iev.ibuf, connfd); 141 c->iev.handler = control_dispatch_imsg; 142 c->iev.events = EV_READ; 143 event_set(&c->iev.ev, c->iev.ibuf.fd, c->iev.events, 144 c->iev.handler, &c->iev); 145 event_add(&c->iev.ev, NULL); 146 147 TAILQ_INSERT_TAIL(&ctl_conns, c, entry); 148 } 149 150 static struct ctl_conn * 151 control_connbyfd(int fd) 152 { 153 struct ctl_conn *c; 154 155 TAILQ_FOREACH(c, &ctl_conns, entry) { 156 if (c->iev.ibuf.fd == fd) 157 break; 158 } 159 160 return (c); 161 } 162 163 static struct ctl_conn * 164 control_connbypid(pid_t pid) 165 { 166 struct ctl_conn *c; 167 168 TAILQ_FOREACH(c, &ctl_conns, entry) { 169 if (c->iev.ibuf.pid == pid) 170 break; 171 } 172 173 return (c); 174 } 175 176 static void 177 control_close(int fd) 178 { 179 struct ctl_conn *c; 180 181 if ((c = control_connbyfd(fd)) == NULL) { 182 log_warnx("%s: fd %d: not found", __func__, fd); 183 return; 184 } 185 186 msgbuf_clear(&c->iev.ibuf.w); 187 TAILQ_REMOVE(&ctl_conns, c, entry); 188 189 event_del(&c->iev.ev); 190 close(c->iev.ibuf.fd); 191 192 /* Some file descriptors are available again. */ 193 if (evtimer_pending(&control_state.evt, NULL)) { 194 evtimer_del(&control_state.evt); 195 event_add(&control_state.ev, NULL); 196 } 197 198 free(c); 199 } 200 201 /* ARGSUSED */ 202 static void 203 control_dispatch_imsg(int fd, short event, void *bula) 204 { 205 struct ctl_conn *c; 206 struct imsg imsg; 207 ssize_t n; 208 unsigned int ifidx; 209 int verbose; 210 211 if ((c = control_connbyfd(fd)) == NULL) { 212 log_warnx("%s: fd %d: not found", __func__, fd); 213 return; 214 } 215 216 if (event & EV_READ) { 217 if (((n = imsg_read(&c->iev.ibuf)) == -1 && errno != EAGAIN) || 218 n == 0) { 219 control_close(fd); 220 return; 221 } 222 } 223 if (event & EV_WRITE) { 224 if (msgbuf_write(&c->iev.ibuf.w) <= 0 && errno != EAGAIN) { 225 control_close(fd); 226 return; 227 } 228 } 229 230 for (;;) { 231 if ((n = imsg_get(&c->iev.ibuf, &imsg)) == -1) { 232 control_close(fd); 233 return; 234 } 235 236 if (n == 0) 237 break; 238 239 switch (imsg.hdr.type) { 240 case IMSG_CTL_FIB_COUPLE: 241 case IMSG_CTL_FIB_DECOUPLE: 242 case IMSG_CTL_RELOAD: 243 c->iev.ibuf.pid = imsg.hdr.pid; 244 eigrpe_imsg_compose_parent(imsg.hdr.type, 0, NULL, 0); 245 break; 246 case IMSG_CTL_KROUTE: 247 case IMSG_CTL_IFINFO: 248 c->iev.ibuf.pid = imsg.hdr.pid; 249 eigrpe_imsg_compose_parent(imsg.hdr.type, imsg.hdr.pid, 250 imsg.data, imsg.hdr.len - IMSG_HEADER_SIZE); 251 break; 252 case IMSG_CTL_SHOW_INTERFACE: 253 if (imsg.hdr.len != IMSG_HEADER_SIZE + 254 sizeof(ifidx)) 255 break; 256 257 memcpy(&ifidx, imsg.data, sizeof(ifidx)); 258 eigrpe_iface_ctl(c, ifidx); 259 imsg_compose_event(&c->iev, IMSG_CTL_END, 0, 260 0, -1, NULL, 0); 261 break; 262 case IMSG_CTL_SHOW_TOPOLOGY: 263 if (imsg.hdr.len != IMSG_HEADER_SIZE + 264 sizeof(struct ctl_show_topology_req)) 265 break; 266 267 c->iev.ibuf.pid = imsg.hdr.pid; 268 eigrpe_imsg_compose_rde(imsg.hdr.type, 0, imsg.hdr.pid, 269 imsg.data, imsg.hdr.len - IMSG_HEADER_SIZE); 270 break; 271 case IMSG_CTL_SHOW_NBR: 272 eigrpe_nbr_ctl(c); 273 break; 274 case IMSG_CTL_SHOW_STATS: 275 eigrpe_stats_ctl(c); 276 break; 277 case IMSG_CTL_CLEAR_NBR: 278 if (imsg.hdr.len != IMSG_HEADER_SIZE + 279 sizeof(struct ctl_nbr)) 280 break; 281 282 nbr_clear_ctl(imsg.data); 283 break; 284 case IMSG_CTL_LOG_VERBOSE: 285 if (imsg.hdr.len != IMSG_HEADER_SIZE + 286 sizeof(verbose)) 287 break; 288 289 /* forward to other processes */ 290 eigrpe_imsg_compose_parent(imsg.hdr.type, imsg.hdr.pid, 291 imsg.data, imsg.hdr.len - IMSG_HEADER_SIZE); 292 eigrpe_imsg_compose_rde(imsg.hdr.type, 0, imsg.hdr.pid, 293 imsg.data, imsg.hdr.len - IMSG_HEADER_SIZE); 294 295 memcpy(&verbose, imsg.data, sizeof(verbose)); 296 log_verbose(verbose); 297 break; 298 default: 299 log_debug("%s: error handling imsg %d", __func__, 300 imsg.hdr.type); 301 break; 302 } 303 imsg_free(&imsg); 304 } 305 306 imsg_event_add(&c->iev); 307 } 308 309 int 310 control_imsg_relay(struct imsg *imsg) 311 { 312 struct ctl_conn *c; 313 314 if ((c = control_connbypid(imsg->hdr.pid)) == NULL) 315 return (0); 316 317 return (imsg_compose_event(&c->iev, imsg->hdr.type, 0, imsg->hdr.pid, 318 -1, imsg->data, imsg->hdr.len - IMSG_HEADER_SIZE)); 319 } 320