1 /* $OpenBSD: control.c,v 1.31 2021/01/19 15:14:35 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/un.h> 22 #include <errno.h> 23 #include <stdlib.h> 24 #include <string.h> 25 #include <unistd.h> 26 27 #include "ldpd.h" 28 #include "ldpe.h" 29 #include "log.h" 30 #include "control.h" 31 32 TAILQ_HEAD(ctl_conns, ctl_conn) ctl_conns = TAILQ_HEAD_INITIALIZER(ctl_conns); 33 34 #define CONTROL_BACKLOG 5 35 36 static void control_accept(int, short, void *); 37 static struct ctl_conn *control_connbyfd(int); 38 static struct ctl_conn *control_connbypid(pid_t); 39 static void control_close(int); 40 static void control_dispatch_imsg(int, short, void *); 41 42 static int control_fd; 43 44 int 45 control_init(char *path) 46 { 47 struct sockaddr_un sun; 48 int fd; 49 mode_t old_umask; 50 51 if ((fd = socket(AF_UNIX, SOCK_STREAM | SOCK_CLOEXEC | SOCK_NONBLOCK, 52 0)) == -1) { 53 log_warn("%s: socket", __func__); 54 return (-1); 55 } 56 57 memset(&sun, 0, sizeof(sun)); 58 sun.sun_family = AF_UNIX; 59 strlcpy(sun.sun_path, path, sizeof(sun.sun_path)); 60 61 if (unlink(path) == -1) 62 if (errno != ENOENT) { 63 log_warn("%s: unlink %s", __func__, path); 64 close(fd); 65 return (-1); 66 } 67 68 old_umask = umask(S_IXUSR|S_IXGRP|S_IWOTH|S_IROTH|S_IXOTH); 69 if (bind(fd, (struct sockaddr *)&sun, sizeof(sun)) == -1) { 70 log_warn("%s: bind: %s", __func__, path); 71 close(fd); 72 umask(old_umask); 73 return (-1); 74 } 75 umask(old_umask); 76 77 if (chmod(path, S_IRUSR|S_IWUSR|S_IRGRP|S_IWGRP) == -1) { 78 log_warn("%s: chmod", __func__); 79 close(fd); 80 (void)unlink(path); 81 return (-1); 82 } 83 84 control_fd = fd; 85 86 return (0); 87 } 88 89 int 90 control_listen(void) 91 { 92 if (listen(control_fd, CONTROL_BACKLOG) == -1) { 93 log_warn("%s: listen", __func__); 94 return (-1); 95 } 96 97 return (accept_add(control_fd, control_accept, NULL)); 98 } 99 100 void 101 control_cleanup(void) 102 { 103 accept_del(control_fd); 104 close(control_fd); 105 } 106 107 /* ARGSUSED */ 108 static void 109 control_accept(int listenfd, short event, void *bula) 110 { 111 int connfd; 112 socklen_t len; 113 struct sockaddr_un sun; 114 struct ctl_conn *c; 115 116 len = sizeof(sun); 117 if ((connfd = accept4(listenfd, (struct sockaddr *)&sun, &len, 118 SOCK_NONBLOCK | SOCK_CLOEXEC)) == -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 accept_pause(); 125 else if (errno != EWOULDBLOCK && errno != EINTR && 126 errno != ECONNABORTED) 127 log_warn("%s: accept4", __func__); 128 return; 129 } 130 131 if ((c = calloc(1, sizeof(struct ctl_conn))) == NULL) { 132 log_warn(__func__); 133 close(connfd); 134 return; 135 } 136 137 imsg_init(&c->iev.ibuf, connfd); 138 c->iev.handler = control_dispatch_imsg; 139 c->iev.events = EV_READ; 140 event_set(&c->iev.ev, c->iev.ibuf.fd, c->iev.events, 141 c->iev.handler, &c->iev); 142 event_add(&c->iev.ev, NULL); 143 144 TAILQ_INSERT_TAIL(&ctl_conns, c, entry); 145 } 146 147 static struct ctl_conn * 148 control_connbyfd(int fd) 149 { 150 struct ctl_conn *c; 151 152 TAILQ_FOREACH(c, &ctl_conns, entry) { 153 if (c->iev.ibuf.fd == fd) 154 break; 155 } 156 157 return (c); 158 } 159 160 static struct ctl_conn * 161 control_connbypid(pid_t pid) 162 { 163 struct ctl_conn *c; 164 165 TAILQ_FOREACH(c, &ctl_conns, entry) { 166 if (c->iev.ibuf.pid == pid) 167 break; 168 } 169 170 return (c); 171 } 172 173 static void 174 control_close(int fd) 175 { 176 struct ctl_conn *c; 177 178 if ((c = control_connbyfd(fd)) == NULL) { 179 log_warnx("%s: fd %d: not found", __func__, fd); 180 return; 181 } 182 183 msgbuf_clear(&c->iev.ibuf.w); 184 TAILQ_REMOVE(&ctl_conns, c, entry); 185 186 event_del(&c->iev.ev); 187 close(c->iev.ibuf.fd); 188 accept_unpause(); 189 free(c); 190 } 191 192 /* ARGSUSED */ 193 static void 194 control_dispatch_imsg(int fd, short event, void *bula) 195 { 196 struct ctl_conn *c; 197 struct imsg imsg; 198 ssize_t n; 199 unsigned int ifidx; 200 int verbose; 201 202 if ((c = control_connbyfd(fd)) == NULL) { 203 log_warnx("%s: fd %d: not found", __func__, fd); 204 return; 205 } 206 207 if (event & EV_READ) { 208 if (((n = imsg_read(&c->iev.ibuf)) == -1 && errno != EAGAIN) || 209 n == 0) { 210 control_close(fd); 211 return; 212 } 213 } 214 if (event & EV_WRITE) { 215 if (msgbuf_write(&c->iev.ibuf.w) <= 0 && errno != EAGAIN) { 216 control_close(fd); 217 return; 218 } 219 } 220 221 for (;;) { 222 if ((n = imsg_get(&c->iev.ibuf, &imsg)) == -1) { 223 control_close(fd); 224 return; 225 } 226 227 if (n == 0) 228 break; 229 230 switch (imsg.hdr.type) { 231 case IMSG_CTL_FIB_COUPLE: 232 case IMSG_CTL_FIB_DECOUPLE: 233 case IMSG_CTL_RELOAD: 234 c->iev.ibuf.pid = imsg.hdr.pid; 235 ldpe_imsg_compose_parent(imsg.hdr.type, 0, NULL, 0); 236 break; 237 case IMSG_CTL_KROUTE: 238 case IMSG_CTL_KROUTE_ADDR: 239 case IMSG_CTL_IFINFO: 240 c->iev.ibuf.pid = imsg.hdr.pid; 241 ldpe_imsg_compose_parent(imsg.hdr.type, 242 imsg.hdr.pid, imsg.data, 243 imsg.hdr.len - IMSG_HEADER_SIZE); 244 break; 245 case IMSG_CTL_SHOW_INTERFACE: 246 if (imsg.hdr.len == IMSG_HEADER_SIZE + 247 sizeof(ifidx)) { 248 memcpy(&ifidx, imsg.data, sizeof(ifidx)); 249 ldpe_iface_ctl(c, ifidx); 250 imsg_compose_event(&c->iev, IMSG_CTL_END, 0, 251 0, -1, NULL, 0); 252 } 253 break; 254 case IMSG_CTL_SHOW_DISCOVERY: 255 ldpe_adj_ctl(c); 256 break; 257 case IMSG_CTL_SHOW_LIB: 258 case IMSG_CTL_SHOW_L2VPN_PW: 259 case IMSG_CTL_SHOW_L2VPN_BINDING: 260 c->iev.ibuf.pid = imsg.hdr.pid; 261 ldpe_imsg_compose_lde(imsg.hdr.type, 0, imsg.hdr.pid, 262 imsg.data, imsg.hdr.len - IMSG_HEADER_SIZE); 263 break; 264 case IMSG_CTL_SHOW_NBR: 265 ldpe_nbr_ctl(c); 266 break; 267 case IMSG_CTL_CLEAR_NBR: 268 if (imsg.hdr.len != IMSG_HEADER_SIZE + 269 sizeof(struct ctl_nbr)) 270 break; 271 272 nbr_clear_ctl(imsg.data); 273 break; 274 case IMSG_CTL_LOG_VERBOSE: 275 if (imsg.hdr.len != IMSG_HEADER_SIZE + 276 sizeof(verbose)) 277 break; 278 279 /* forward to other processes */ 280 ldpe_imsg_compose_parent(imsg.hdr.type, imsg.hdr.pid, 281 imsg.data, imsg.hdr.len - IMSG_HEADER_SIZE); 282 ldpe_imsg_compose_lde(imsg.hdr.type, 0, imsg.hdr.pid, 283 imsg.data, imsg.hdr.len - IMSG_HEADER_SIZE); 284 285 memcpy(&verbose, imsg.data, sizeof(verbose)); 286 log_verbose(verbose); 287 break; 288 default: 289 log_debug("%s: error handling imsg %d", __func__, 290 imsg.hdr.type); 291 break; 292 } 293 imsg_free(&imsg); 294 } 295 296 imsg_event_add(&c->iev); 297 } 298 299 int 300 control_imsg_relay(struct imsg *imsg) 301 { 302 struct ctl_conn *c; 303 304 if ((c = control_connbypid(imsg->hdr.pid)) == NULL) 305 return (0); 306 307 return (imsg_compose_event(&c->iev, imsg->hdr.type, 0, imsg->hdr.pid, 308 -1, imsg->data, imsg->hdr.len - IMSG_HEADER_SIZE)); 309 } 310