1 /* $OpenBSD: control.c,v 1.1 2014/07/12 23:34:54 reyk 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/queue.h> 20 #include <sys/param.h> 21 #include <sys/stat.h> 22 #include <sys/socket.h> 23 #include <sys/un.h> 24 25 #include <net/if.h> 26 27 #include <errno.h> 28 #include <event.h> 29 #include <fcntl.h> 30 #include <stdlib.h> 31 #include <string.h> 32 #include <unistd.h> 33 #include <signal.h> 34 35 #include <openssl/ssl.h> 36 37 #include "httpd.h" 38 39 #define CONTROL_BACKLOG 5 40 41 struct ctl_connlist ctl_conns; 42 43 void control_accept(int, short, void *); 44 void control_close(int, struct control_sock *); 45 46 int 47 control_init(struct privsep *ps, struct control_sock *cs) 48 { 49 struct httpd *env = ps->ps_env; 50 struct sockaddr_un sun; 51 int fd; 52 mode_t old_umask, mode; 53 54 if (cs->cs_name == NULL) 55 return (0); 56 57 if ((fd = socket(AF_UNIX, SOCK_STREAM, 0)) == -1) { 58 log_warn("%s: socket", __func__); 59 return (-1); 60 } 61 62 sun.sun_family = AF_UNIX; 63 if (strlcpy(sun.sun_path, cs->cs_name, 64 sizeof(sun.sun_path)) >= sizeof(sun.sun_path)) { 65 log_warn("%s: %s name too long", __func__, cs->cs_name); 66 close(fd); 67 return (-1); 68 } 69 70 if (unlink(cs->cs_name) == -1) 71 if (errno != ENOENT) { 72 log_warn("%s: unlink %s", __func__, cs->cs_name); 73 close(fd); 74 return (-1); 75 } 76 77 if (cs->cs_restricted) { 78 old_umask = umask(S_IXUSR|S_IXGRP|S_IXOTH); 79 mode = S_IRUSR|S_IWUSR|S_IRGRP|S_IWGRP|S_IROTH|S_IWOTH; 80 } else { 81 old_umask = umask(S_IXUSR|S_IXGRP|S_IWOTH|S_IROTH|S_IXOTH); 82 mode = S_IRUSR|S_IWUSR|S_IRGRP|S_IWGRP; 83 } 84 85 if (bind(fd, (struct sockaddr *)&sun, sizeof(sun)) == -1) { 86 log_warn("%s: bind: %s", __func__, cs->cs_name); 87 close(fd); 88 (void)umask(old_umask); 89 return (-1); 90 } 91 (void)umask(old_umask); 92 93 if (chmod(cs->cs_name, mode) == -1) { 94 log_warn("%s: chmod", __func__); 95 close(fd); 96 (void)unlink(cs->cs_name); 97 return (-1); 98 } 99 100 socket_set_blockmode(fd, BM_NONBLOCK); 101 cs->cs_fd = fd; 102 cs->cs_env = env; 103 104 return (0); 105 } 106 107 int 108 control_listen(struct control_sock *cs) 109 { 110 if (cs->cs_name == NULL) 111 return (0); 112 113 if (listen(cs->cs_fd, CONTROL_BACKLOG) == -1) { 114 log_warn("%s: listen", __func__); 115 return (-1); 116 } 117 118 event_set(&cs->cs_ev, cs->cs_fd, EV_READ, 119 control_accept, cs); 120 event_add(&cs->cs_ev, NULL); 121 evtimer_set(&cs->cs_evt, control_accept, cs); 122 123 return (0); 124 } 125 126 void 127 control_cleanup(struct control_sock *cs) 128 { 129 if (cs->cs_name == NULL) 130 return; 131 event_del(&cs->cs_ev); 132 event_del(&cs->cs_evt); 133 (void)unlink(cs->cs_name); 134 } 135 136 /* ARGSUSED */ 137 void 138 control_accept(int listenfd, short event, void *arg) 139 { 140 int connfd; 141 socklen_t len; 142 struct sockaddr_un sun; 143 struct ctl_conn *c; 144 struct control_sock *cs = arg; 145 146 event_add(&cs->cs_ev, NULL); 147 if ((event & EV_TIMEOUT)) 148 return; 149 150 len = sizeof(sun); 151 if ((connfd = accept(listenfd, 152 (struct sockaddr *)&sun, &len)) == -1) { 153 /* 154 * Pause accept if we are out of file descriptors, or 155 * libevent will haunt us here too. 156 */ 157 if (errno == ENFILE || errno == EMFILE) { 158 struct timeval evtpause = { 1, 0 }; 159 160 event_del(&cs->cs_ev); 161 evtimer_add(&cs->cs_evt, &evtpause); 162 } else if (errno != EWOULDBLOCK && errno != EINTR && 163 errno != ECONNABORTED) 164 log_warn("%s: accept", __func__); 165 return; 166 } 167 168 socket_set_blockmode(connfd, BM_NONBLOCK); 169 170 if ((c = calloc(1, sizeof(struct ctl_conn))) == NULL) { 171 close(connfd); 172 log_warn("%s: calloc", __func__); 173 return; 174 } 175 176 imsg_init(&c->iev.ibuf, connfd); 177 c->iev.handler = control_dispatch_imsg; 178 c->iev.events = EV_READ; 179 c->iev.data = cs; /* proc.c cheats (reuses the handler) */ 180 event_set(&c->iev.ev, c->iev.ibuf.fd, c->iev.events, 181 c->iev.handler, cs); 182 event_add(&c->iev.ev, NULL); 183 184 TAILQ_INSERT_TAIL(&ctl_conns, c, entry); 185 } 186 187 struct ctl_conn * 188 control_connbyfd(int fd) 189 { 190 struct ctl_conn *c; 191 192 for (c = TAILQ_FIRST(&ctl_conns); c != NULL && c->iev.ibuf.fd != fd; 193 c = TAILQ_NEXT(c, entry)) 194 ; /* nothing */ 195 196 return (c); 197 } 198 199 void 200 control_close(int fd, struct control_sock *cs) 201 { 202 struct ctl_conn *c; 203 204 if ((c = control_connbyfd(fd)) == NULL) { 205 log_warn("%s: fd %d not found", __func__, fd); 206 return; 207 } 208 209 msgbuf_clear(&c->iev.ibuf.w); 210 TAILQ_REMOVE(&ctl_conns, c, entry); 211 212 event_del(&c->iev.ev); 213 close(c->iev.ibuf.fd); 214 215 /* Some file descriptors are available again. */ 216 if (evtimer_pending(&cs->cs_evt, NULL)) { 217 evtimer_del(&cs->cs_evt); 218 event_add(&cs->cs_ev, NULL); 219 } 220 221 free(c); 222 } 223 224 /* ARGSUSED */ 225 void 226 control_dispatch_imsg(int fd, short event, void *arg) 227 { 228 struct control_sock *cs = arg; 229 struct ctl_conn *c; 230 struct imsg imsg; 231 int n; 232 int verbose; 233 struct httpd *env = cs->cs_env; 234 235 if ((c = control_connbyfd(fd)) == NULL) { 236 log_warn("%s: fd %d not found", __func__, fd); 237 return; 238 } 239 240 if (event & EV_READ) { 241 if ((n = imsg_read(&c->iev.ibuf)) == -1 || n == 0) { 242 control_close(fd, cs); 243 return; 244 } 245 } 246 247 if (event & EV_WRITE) { 248 if (msgbuf_write(&c->iev.ibuf.w) <= 0 && errno != EAGAIN) { 249 control_close(fd, cs); 250 return; 251 } 252 } 253 254 for (;;) { 255 if ((n = imsg_get(&c->iev.ibuf, &imsg)) == -1) { 256 control_close(fd, cs); 257 return; 258 } 259 260 if (n == 0) 261 break; 262 263 if (c->waiting) { 264 log_debug("%s: unexpected imsg %d", 265 __func__, imsg.hdr.type); 266 imsg_free(&imsg); 267 control_close(fd, cs); 268 return; 269 } 270 271 switch (imsg.hdr.type) { 272 case IMSG_CTL_SHUTDOWN: 273 case IMSG_CTL_RELOAD: 274 proc_forward_imsg(env->sc_ps, &imsg, PROC_PARENT, -1); 275 break; 276 case IMSG_CTL_NOTIFY: 277 if (c->flags & CTL_CONN_NOTIFY) { 278 log_debug("%s: " 279 "client requested notify more than once", 280 __func__); 281 imsg_compose_event(&c->iev, IMSG_CTL_FAIL, 282 0, 0, -1, NULL, 0); 283 break; 284 } 285 c->flags |= CTL_CONN_NOTIFY; 286 break; 287 case IMSG_CTL_VERBOSE: 288 IMSG_SIZE_CHECK(&imsg, &verbose); 289 290 memcpy(&verbose, imsg.data, sizeof(verbose)); 291 292 proc_forward_imsg(env->sc_ps, &imsg, PROC_PARENT, -1); 293 proc_forward_imsg(env->sc_ps, &imsg, PROC_SERVER, -1); 294 295 memcpy(imsg.data, &verbose, sizeof(verbose)); 296 control_imsg_forward(&imsg); 297 log_verbose(verbose); 298 break; 299 default: 300 log_debug("%s: error handling imsg %d", 301 __func__, imsg.hdr.type); 302 break; 303 } 304 imsg_free(&imsg); 305 } 306 307 imsg_event_add(&c->iev); 308 } 309 310 void 311 control_imsg_forward(struct imsg *imsg) 312 { 313 struct ctl_conn *c; 314 315 TAILQ_FOREACH(c, &ctl_conns, entry) 316 if (c->flags & CTL_CONN_NOTIFY) 317 imsg_compose_event(&c->iev, imsg->hdr.type, 318 0, imsg->hdr.pid, -1, imsg->data, 319 imsg->hdr.len - IMSG_HEADER_SIZE); 320 } 321 322 void 323 socket_set_blockmode(int fd, enum blockmodes bm) 324 { 325 int flags; 326 327 if ((flags = fcntl(fd, F_GETFL, 0)) == -1) 328 fatal("fcntl F_GETFL"); 329 330 if (bm == BM_NONBLOCK) 331 flags |= O_NONBLOCK; 332 else 333 flags &= ~O_NONBLOCK; 334 335 if ((flags = fcntl(fd, F_SETFL, flags)) == -1) 336 fatal("fcntl F_SETFL"); 337 } 338