1 /* $OpenBSD: control.c,v 1.34 2024/11/21 13:38:15 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 "ripd.h" 30 #include "rip.h" 31 #include "ripe.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_init(char *path) 51 { 52 struct sockaddr_un sun; 53 int fd; 54 mode_t old_umask; 55 56 if ((fd = socket(AF_UNIX, SOCK_STREAM | SOCK_CLOEXEC | SOCK_NONBLOCK, 57 0)) == -1) { 58 log_warn("control_init: socket"); 59 return (-1); 60 } 61 62 bzero(&sun, sizeof(sun)); 63 sun.sun_family = AF_UNIX; 64 strlcpy(sun.sun_path, path, sizeof(sun.sun_path)); 65 66 if (unlink(path) == -1) 67 if (errno != ENOENT) { 68 log_warn("control_init: unlink %s", path); 69 close(fd); 70 return (-1); 71 } 72 73 old_umask = umask(S_IXUSR|S_IXGRP|S_IWOTH|S_IROTH|S_IXOTH); 74 if (bind(fd, (struct sockaddr *)&sun, sizeof(sun)) == -1) { 75 log_warn("control_init: bind: %s", path); 76 close(fd); 77 umask(old_umask); 78 return (-1); 79 } 80 umask(old_umask); 81 82 if (chmod(path, S_IRUSR|S_IWUSR|S_IRGRP|S_IWGRP) == -1) { 83 log_warn("control_init: chmod"); 84 close(fd); 85 (void)unlink(path); 86 return (-1); 87 } 88 89 control_state.fd = fd; 90 91 return (0); 92 } 93 94 int 95 control_listen(void) 96 { 97 if (listen(control_state.fd, CONTROL_BACKLOG) == -1) { 98 log_warn("control_listen: listen"); 99 return (-1); 100 } 101 102 event_set(&control_state.ev, control_state.fd, EV_READ, 103 control_accept, NULL); 104 event_add(&control_state.ev, NULL); 105 evtimer_set(&control_state.evt, control_accept, NULL); 106 107 return (0); 108 } 109 110 void 111 control_accept(int listenfd, short event, void *bula) 112 { 113 int connfd; 114 socklen_t len; 115 struct sockaddr_un sun; 116 struct ctl_conn *c; 117 118 event_add(&control_state.ev, NULL); 119 if ((event & EV_TIMEOUT)) 120 return; 121 122 len = sizeof(sun); 123 if ((connfd = accept4(listenfd, (struct sockaddr *)&sun, &len, 124 SOCK_CLOEXEC | SOCK_NONBLOCK)) == -1) { 125 /* 126 * Pause accept if we are out of file descriptors, or 127 * libevent will haunt us here too. 128 */ 129 if (errno == ENFILE || errno == EMFILE) { 130 struct timeval evtpause = { 1, 0 }; 131 132 event_del(&control_state.ev); 133 evtimer_add(&control_state.evt, &evtpause); 134 } else if (errno != EWOULDBLOCK && errno != EINTR && 135 errno != ECONNABORTED) 136 log_warn("control_accept: accept"); 137 return; 138 } 139 140 if ((c = calloc(1, sizeof(struct ctl_conn))) == NULL) { 141 log_warn("control_accept"); 142 close(connfd); 143 return; 144 } 145 146 if (imsgbuf_init(&c->iev.ibuf, connfd) == -1) { 147 log_warn("control_accept"); 148 close(connfd); 149 free(c); 150 return; 151 } 152 c->iev.handler = control_dispatch_imsg; 153 c->iev.events = EV_READ; 154 event_set(&c->iev.ev, c->iev.ibuf.fd, c->iev.events, 155 c->iev.handler, &c->iev); 156 event_add(&c->iev.ev, NULL); 157 158 TAILQ_INSERT_TAIL(&ctl_conns, c, entry); 159 } 160 161 struct ctl_conn * 162 control_connbyfd(int fd) 163 { 164 struct ctl_conn *c; 165 166 TAILQ_FOREACH(c, &ctl_conns, entry) { 167 if (c->iev.ibuf.fd == fd) 168 break; 169 } 170 171 return (c); 172 } 173 174 struct ctl_conn * 175 control_connbypid(pid_t pid) 176 { 177 struct ctl_conn *c; 178 179 TAILQ_FOREACH(c, &ctl_conns, entry) { 180 if (c->iev.ibuf.pid == pid) 181 break; 182 } 183 184 return (c); 185 } 186 187 void 188 control_close(int fd) 189 { 190 struct ctl_conn *c; 191 192 if ((c = control_connbyfd(fd)) == NULL) { 193 log_warn("control_close: fd %d: not found", fd); 194 return; 195 } 196 197 imsgbuf_clear(&c->iev.ibuf); 198 TAILQ_REMOVE(&ctl_conns, c, entry); 199 200 event_del(&c->iev.ev); 201 close(c->iev.ibuf.fd); 202 203 /* Some file descriptors are available again. */ 204 if (evtimer_pending(&control_state.evt, NULL)) { 205 evtimer_del(&control_state.evt); 206 event_add(&control_state.ev, NULL); 207 } 208 209 free(c); 210 } 211 212 void 213 control_dispatch_imsg(int fd, short event, void *bula) 214 { 215 struct ctl_conn *c; 216 struct imsg imsg; 217 ssize_t n; 218 unsigned int ifidx; 219 int verbose; 220 221 if ((c = control_connbyfd(fd)) == NULL) { 222 log_warn("control_dispatch_imsg: fd %d: not found", fd); 223 return; 224 } 225 226 if (event & EV_READ) { 227 if (imsgbuf_read(&c->iev.ibuf) != 1) { 228 control_close(fd); 229 return; 230 } 231 } 232 if (event & EV_WRITE) { 233 if (imsgbuf_write(&c->iev.ibuf) == -1) { 234 control_close(fd); 235 return; 236 } 237 } 238 239 for (;;) { 240 if ((n = imsg_get(&c->iev.ibuf, &imsg)) == -1) { 241 control_close(fd); 242 return; 243 } 244 245 if (n == 0) 246 break; 247 248 switch (imsg.hdr.type) { 249 case IMSG_CTL_SHOW_INTERFACE: 250 if (imsg.hdr.len - IMSG_HEADER_SIZE != sizeof(ifidx)) 251 return; 252 253 memcpy(&ifidx, imsg.data, sizeof(ifidx)); 254 ripe_iface_ctl(c, ifidx); 255 imsg_compose(&c->iev.ibuf, IMSG_CTL_END, 0, 0, 256 -1, NULL, 0); 257 258 break; 259 case IMSG_CTL_SHOW_RIB: 260 c->iev.ibuf.pid = imsg.hdr.pid; 261 ripe_imsg_compose_rde(imsg.hdr.type, 0, 262 imsg.hdr.pid, imsg.data, imsg.hdr.len - 263 IMSG_HEADER_SIZE); 264 break; 265 case IMSG_CTL_SHOW_NBR: 266 ripe_nbr_ctl(c); 267 break; 268 case IMSG_CTL_KROUTE_ADDR: 269 case IMSG_CTL_KROUTE: 270 case IMSG_CTL_IFINFO: 271 c->iev.ibuf.pid = imsg.hdr.pid; 272 ripe_imsg_compose_parent(imsg.hdr.type, 273 imsg.hdr.pid, imsg.data, 274 imsg.hdr.len - IMSG_HEADER_SIZE); 275 break; 276 case IMSG_CTL_FIB_COUPLE: 277 case IMSG_CTL_FIB_DECOUPLE: 278 case IMSG_CTL_RELOAD: 279 c->iev.ibuf.pid = imsg.hdr.pid; 280 ripe_imsg_compose_parent(imsg.hdr.type, 0, NULL, 0); 281 break; 282 case IMSG_CTL_LOG_VERBOSE: 283 if (imsg.hdr.len != IMSG_HEADER_SIZE + 284 sizeof(verbose)) 285 break; 286 287 /* forward to other processes */ 288 ripe_imsg_compose_parent(imsg.hdr.type, imsg.hdr.pid, 289 imsg.data, imsg.hdr.len - IMSG_HEADER_SIZE); 290 ripe_imsg_compose_rde(imsg.hdr.type, 0, imsg.hdr.pid, 291 imsg.data, imsg.hdr.len - IMSG_HEADER_SIZE); 292 293 memcpy(&verbose, imsg.data, sizeof(verbose)); 294 log_verbose(verbose); 295 break; 296 default: 297 log_debug("control_dispatch_imsg: " 298 "error handling imsg %d", imsg.hdr.type); 299 break; 300 } 301 imsg_free(&imsg); 302 } 303 304 imsg_event_add(&c->iev); 305 } 306 307 int 308 control_imsg_relay(struct imsg *imsg) 309 { 310 struct ctl_conn *c; 311 312 if ((c = control_connbypid(imsg->hdr.pid)) == NULL) 313 return (0); 314 315 return (imsg_compose_event(&c->iev, imsg->hdr.type, 0, imsg->hdr.pid, 316 -1, imsg->data, imsg->hdr.len - IMSG_HEADER_SIZE)); 317 } 318