/* * CDDL HEADER START * * The contents of this file are subject to the terms of the * Common Development and Distribution License, Version 1.0 only * (the "License"). You may not use this file except in compliance * with the License. * * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE * or http://www.opensolaris.org/os/licensing. * See the License for the specific language governing permissions * and limitations under the License. * * When distributing Covered Code, include this CDDL HEADER in each * file and include the License file at usr/src/OPENSOLARIS.LICENSE. * If applicable, add the following below this CDDL HEADER, with the * fields enclosed by brackets "[]" replaced with your own identifying * information: Portions Copyright [yyyy] [name of copyright owner] * * CDDL HEADER END */ /* * Copyright 2004 Sun Microsystems, Inc. All rights reserved. * Use is subject to license terms. */ #pragma ident "%Z%%M% %I% %E% SMI" /* * Console support for zones requires a significant infrastructure. The * core pieces are contained in this file, but other portions of note * are in the zlogin(1M) command, the zcons(7D) driver, and in the * devfsadm(1M) misc_link generator. * * Care is taken to make the console behave in an "intuitive" fashion for * administrators. Essentially, we try as much as possible to mimic the * experience of using a system via a tip line and system controller. * * The zone console architecture looks like this: * * Global Zone | Non-Global Zone * .--------------. | * .-----------. | zoneadmd -z | | .--------. .---------. * | zlogin -C | | myzone | | | ttymon | | syslogd | * `-----------' `--------------' | `--------' `---------' * | | | | | | | * User | | | | | V V * - - - - - - - - -|- - - -|- - - -|-|- - - - - - -|- - /dev/zconsole - - - * Kernel V V | | | * [AF_UNIX Socket] | `--------. .-------------' * | | | * | V V * | +-----------+ * | | ldterm, | * | | etc. | * | +-----------+ * | +-[Anchor]--+ * | | ptem | * V +-----------+ * +---master---+---slave---+ * | | * | zcons driver | * | zonename="myzone" | * +------------------------+ * * There are basically three major tasks which the console subsystem in * zoneadmd accomplishes: * * - Setup and teardown of zcons driver instances. One zcons instance * is maintained per zone; we take advantage of the libdevice APIs * to online new instances of zcons as needed. Care is taken to * prune and manage these appropriately; see init_console_dev() and * destroy_console_dev(). The end result is the creation of the * zcons(7D) instance and an open file descriptor to the master side. * zcons instances are associated with zones via their zonename device * property. This the console instance to persist across reboots, * and while the zone is halted. * * - Initialization of the slave side of the console. This is * accomplished by pushing various STREAMS modules onto the console. * The ptem(7M) module gets special treatment, and is anchored into * place using the I_ANCHOR facility. This is so that the zcons driver * always has terminal semantics, as would a real hardware terminal. * This means that ttymon(1M) works unmodified; at boot time, ttymon * will do its own plumbing of the console stream, and will even * I_POP modules off. Hence the anchor, which assures that ptem will * never be I_POP'd. * * - Acting as a server for 'zlogin -C' instances. When zlogin -C is * run, zlogin connects to zoneadmd via unix domain socket. zoneadmd * functions as a two-way proxy for console I/O, relaying user input * to the master side of the console, and relaying output from the * zone to the user. */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "zoneadmd.h" #define ZCONSNEX_DEVTREEPATH "/pseudo/zconsnex@1" #define ZCONSNEX_FILEPATH "/devices/pseudo/zconsnex@1" #define CONSOLE_SOCKPATH ZONES_TMPDIR "/%s.console_sock" static int slavefd = -1; /* slave side of console */ static int serverfd = -1; /* console server unix domain socket fd */ static struct termios base_termios = { /* from init.c */ BRKINT|ICRNL|IXON|IMAXBEL, /* iflag */ OPOST|ONLCR|TAB3, /* oflag */ CS8|CREAD|B9600, /* cflag */ ISIG|ICANON|ECHO|ECHOE|ECHOK|ECHOCTL|ECHOKE|IEXTEN, /* lflag */ CINTR, CQUIT, CERASE, CKILL, CEOF, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 }; /* * The eventstream is a simple one-directional flow of messages from the * door server to the console subsystem, implemented with a pipe. * It is used to wake up the console poller when it needs to take action, * message the user, die off, etc. */ static int eventstream[2]; int eventstream_init() { if (pipe(eventstream) == -1) return (-1); return (0); } void eventstream_write(zone_evt_t evt) { (void) write(eventstream[0], &evt, sizeof (evt)); } static zone_evt_t eventstream_read(void) { zone_evt_t evt = Z_EVT_NULL; (void) read(eventstream[1], &evt, sizeof (evt)); return (evt); } /* * count_console_devs() and its helper count_cb() do a walk of the * subtree of the device tree where zone console nodes are represented. * The goal is to count zone console instances already setup for a zone * with the given name. More than 1 is anomolous, and our caller will * have to deal with that if we find that's the case. * * Note: this algorithm is a linear search of nodes in the zconsnex subtree * of the device tree, and could be a scalability problem, but I don't see * how to avoid it. */ /* * cb_data is shared by count_cb and destroy_cb for simplicity. */ struct cb_data { zlog_t *zlogp; int found; int killed; }; static int count_cb(di_node_t node, void *arg) { struct cb_data *cb = (struct cb_data *)arg; char *prop_data; if (di_prop_lookup_strings(DDI_DEV_T_ANY, node, "zonename", &prop_data) != -1) { assert(prop_data != NULL); if (strcmp(prop_data, zone_name) == 0) { cb->found++; return (DI_WALK_CONTINUE); } } return (DI_WALK_CONTINUE); } static int count_console_devs(zlog_t *zlogp) { di_node_t root; struct cb_data cb; bzero(&cb, sizeof (cb)); cb.zlogp = zlogp; if ((root = di_init(ZCONSNEX_DEVTREEPATH, DINFOCPYALL)) == DI_NODE_NIL) { zerror(zlogp, B_TRUE, "%s failed", "di_init"); return (-1); } (void) di_walk_node(root, DI_WALK_CLDFIRST, (void *)&cb, count_cb); di_fini(root); return (cb.found); } /* * destroy_console_devs() and its helper destroy_cb() tears down any console * instances associated with this zone. If things went very wrong, we * might have more than one console instance hanging around. This routine * hunts down and tries to remove all of them. Of course, if the console * is open, the instance will not detach, which is a potential issue. */ static int destroy_cb(di_node_t node, void *arg) { struct cb_data *cb = (struct cb_data *)arg; char *prop_data; char *tmp; char devpath[MAXPATHLEN]; devctl_hdl_t hdl; if (di_prop_lookup_strings(DDI_DEV_T_ANY, node, "zonename", &prop_data) == -1) return (DI_WALK_CONTINUE); assert(prop_data != NULL); if (strcmp(prop_data, zone_name) != 0) { /* this is the console for a different zone */ return (DI_WALK_CONTINUE); } cb->found++; tmp = di_devfs_path(node); (void) snprintf(devpath, sizeof (devpath), "/devices/%s", tmp); di_devfs_path_free(tmp); if ((hdl = devctl_device_acquire(devpath, 0)) == NULL) { zerror(cb->zlogp, B_TRUE, "WARNING: console %s found, " "but it could not be controlled.", devpath); return (DI_WALK_CONTINUE); } if (devctl_device_remove(hdl) == 0) { cb->killed++; } else { zerror(cb->zlogp, B_TRUE, "WARNING: console %s found, " "but it could not be removed.", devpath); } devctl_release(hdl); return (DI_WALK_CONTINUE); } static int destroy_console_devs(zlog_t *zlogp) { di_node_t root; struct cb_data cb; bzero(&cb, sizeof (cb)); cb.zlogp = zlogp; if ((root = di_init(ZCONSNEX_DEVTREEPATH, DINFOCPYALL)) == DI_NODE_NIL) { zerror(zlogp, B_TRUE, "%s failed", "di_init"); return (-1); } (void) di_walk_node(root, DI_WALK_CLDFIRST, (void *)&cb, destroy_cb); if (cb.found > 1) { zerror(zlogp, B_FALSE, "WARNING: multiple zone console " "instances detected for zone '%s'; %d of %d " "successfully removed.", zone_name, cb.killed, cb.found); } di_fini(root); return (0); } /* * init_console_dev() drives the device-tree configuration of the zone * console device. The general strategy is to use the libdevice (devctl) * interfaces to instantiate a new zone console node. We do a lot of * sanity checking, and are careful to reuse a console if one exists. * * Once the device is in the device tree, we kick devfsadm via di_init_devs() * to ensure that the appropriate symlinks (to the master and slave console * devices) are placed in /dev in the global zone. */ static int init_console_dev(zlog_t *zlogp) { devctl_hdl_t bus_hdl = NULL, dev_hdl = NULL; devctl_ddef_t ddef_hdl = NULL; di_devlink_handle_t dl = NULL; int rv = -1, ndevs; /* * Don't re-setup console if it is working and ready already; just * skip ahead to making devlinks, which we do for sanity's sake. */ ndevs = count_console_devs(zlogp); if (ndevs == 1) { goto devlinks; } else if (ndevs > 1 || ndevs == -1) { /* * For now, this seems like a reasonable but harsh punishment. * If needed, we could try to get clever and delete all but * the console which is pointed at by the current symlink. */ if (destroy_console_devs(zlogp) == -1) { goto error; } } /* * Time to make the consoles! */ if ((bus_hdl = devctl_bus_acquire(ZCONSNEX_FILEPATH, 0)) == NULL) { zerror(zlogp, B_TRUE, "%s failed", "devctl_bus_acquire"); goto error; } if ((ddef_hdl = devctl_ddef_alloc("zcons", 0)) == NULL) { zerror(zlogp, B_TRUE, "failed to allocate ddef handle"); goto error; } /* * Set three properties on this node; the first is the name of the * zone; the second is a flag which lets pseudo know that it is * OK to automatically allocate an instance # for this device; * the third tells the device framework not to auto-detach this * node-- we need the node to still be there when we ask devfsadmd * to make links, and when we need to open it. */ if (devctl_ddef_string(ddef_hdl, "zonename", zone_name) == -1) { zerror(zlogp, B_TRUE, "failed to create zonename property"); goto error; } if (devctl_ddef_int(ddef_hdl, "auto-assign-instance", 1) == -1) { zerror(zlogp, B_TRUE, "failed to create auto-assign-instance " "property"); goto error; } if (devctl_ddef_int(ddef_hdl, "ddi-no-autodetach", 1) == -1) { zerror(zlogp, B_TRUE, "failed to create ddi-no-auto-detach " "property"); goto error; } if (devctl_bus_dev_create(bus_hdl, ddef_hdl, 0, &dev_hdl) == -1) { zerror(zlogp, B_TRUE, "failed to create console node"); goto error; } devlinks: if ((dl = di_devlink_init("zcons", DI_MAKE_LINK)) != NULL) { (void) di_devlink_fini(&dl); } else { zerror(zlogp, B_TRUE, "failed to create devlinks"); goto error; } rv = 0; error: if (ddef_hdl) devctl_ddef_free(ddef_hdl); if (bus_hdl) devctl_release(bus_hdl); if (dev_hdl) devctl_release(dev_hdl); return (rv); } /* * prep_console_slave() takes care of setting up the console slave device * (the side that the zone will eventually open). It is a helper for * init_console_slave(). * * We have to mknod and setup the console device; then the slave side is * opened, and the appropriate STREAMS modules are pushed on. A wrinkle is that * 'ptem' must be anchored in place (see streamio(7i) since we always want the * console to have terminal semantics. */ static int prep_console_slave(zlog_t *zlogp, char *zonepath) { char slavename[MAXPATHLEN]; char zoneslavename[MAXPATHLEN]; struct stat st; assert(slavefd == -1); (void) snprintf(slavename, sizeof (slavename), "/dev/zcons/%s/%s", zone_name, ZCONS_SLAVE_NAME); (void) snprintf(zoneslavename, sizeof (zoneslavename), "%s/dev/zconsole", zonepath); /* * We mknod the zone console in $zonepath/dev/; someday it would * be nice to not have to manually mknod this stuff-- if possible, * we could move this into devfsadm. */ if (stat(slavename, &st) == -1) { zerror(zlogp, B_TRUE, "failed to stat %s", slavename); goto error; } (void) unlink(zoneslavename); if (mknod(zoneslavename, st.st_mode, st.st_rdev) == -1) { zerror(zlogp, B_TRUE, "failed to mknod %s", zoneslavename); goto error; } (void) chown(zoneslavename, st.st_uid, st.st_gid); if ((slavefd = open(zoneslavename, O_RDWR | O_NOCTTY)) < 0) { zerror(zlogp, B_TRUE, "failed to open %s", zoneslavename); return (-1); } /* * Just to make sure the whole stream is pristine. */ (void) ioctl(slavefd, I_FLUSH, FLUSHRW); /* * Push hardware emulation (ptem) module; we would rather not, but * are forced to push ldterm and ttcompat here. Ultimately ttymon * will pop them off, so we ANCHOR only ptem. * * We need to use __I_PUSH_NOCTTY instead of I_PUSH here, otherwise * we'll end up having the slave device as *our* controling terminal. */ if (ioctl(slavefd, __I_PUSH_NOCTTY, "ptem") == -1) { zerror(zlogp, B_TRUE, "failed to push ptem module"); goto error; } /* * Anchor the stream to prevent malicious or accidental I_POP of ptem. */ if (ioctl(slavefd, I_ANCHOR) == -1) { zerror(zlogp, B_TRUE, "failed to set stream anchor"); goto error; } if (ioctl(slavefd, __I_PUSH_NOCTTY, "ldterm") == -1) { zerror(zlogp, B_TRUE, "failed to push ldterm module"); goto error; } if (ioctl(slavefd, __I_PUSH_NOCTTY, "ttcompat") == -1) { zerror(zlogp, B_TRUE, "failed to push ttcompat module"); goto error; } /* * Setup default terminal settings */ if (tcsetattr(slavefd, TCSAFLUSH, &base_termios) == -1) { zerror(zlogp, B_TRUE, "failed to set base terminal settings"); goto error; } return (0); error: (void) close(slavefd); slavefd = -1; return (-1); } /* * init_console_slave() sets up the console slave device; the device node * itself has already been set up in the device tree; the primary job * here is to do some STREAMS plumbing (via prep_console_slave()) and then * to establish some symlinks. Eventually we should move that functionality * into devfsadm. */ int init_console_slave(zlog_t *zlogp) { char zonepath[MAXPATHLEN]; if (slavefd != -1) return (0); if (zone_get_zonepath(zone_name, zonepath, sizeof (zonepath)) != Z_OK) { zerror(zlogp, B_TRUE, "unable to determine zone root"); return (-1); } if (prep_console_slave(zlogp, zonepath) == -1) { zerror(zlogp, B_FALSE, "could not prep console slave"); return (-1); } return (0); } void destroy_console_slave(void) { (void) close(slavefd); slavefd = -1; } /* * Restore initial terminal attributes to the zone console. */ void reset_slave_terminal(zlog_t *zlogp) { assert(slavefd != -1); /* Probably not fatal, so we drive on if it fails */ if (tcsetattr(slavefd, TCSAFLUSH, &base_termios) == -1) { zerror(zlogp, B_TRUE, "WARNING: failed to set terminal " "settings."); } } static int init_console_sock(zlog_t *zlogp) { int servfd; struct sockaddr_un servaddr; bzero(&servaddr, sizeof (servaddr)); servaddr.sun_family = AF_UNIX; (void) snprintf(servaddr.sun_path, sizeof (servaddr.sun_path), CONSOLE_SOCKPATH, zone_name); if ((servfd = socket(AF_UNIX, SOCK_STREAM, 0)) == -1) { zerror(zlogp, B_TRUE, "console setup: could not create socket"); return (-1); } (void) unlink(servaddr.sun_path); if (bind(servfd, (struct sockaddr *)&servaddr, sizeof (servaddr)) == -1) { zerror(zlogp, B_TRUE, "console setup: could not bind to socket"); goto out; } if (listen(servfd, 4) == -1) { zerror(zlogp, B_TRUE, "console setup: could not listen on socket"); goto out; } return (servfd); out: (void) unlink(servaddr.sun_path); (void) close(servfd); return (-1); } static void destroy_console_sock(int servfd) { char path[MAXPATHLEN]; (void) snprintf(path, sizeof (path), CONSOLE_SOCKPATH, zone_name); (void) unlink(path); (void) shutdown(servfd, SHUT_RDWR); (void) close(servfd); } /* * Read the "ident" string from the client's descriptor; this routine also * tolerates being called with pid=NULL, for times when you want to "eat" * the ident string from a client without saving it. */ static int get_client_ident(int clifd, pid_t *pid, char *locale, size_t locale_len) { char buf[BUFSIZ], *bufp; size_t buflen = sizeof (buf); char c = '\0'; int i = 0, r; /* "eat up the ident string" case, for simplicity */ if (pid == NULL) { assert(locale == NULL && locale_len == 0); while (read(clifd, &c, 1) == 1) { if (c == '\n') return (0); } } bzero(buf, sizeof (buf)); while ((buflen > 1) && (r = read(clifd, &c, 1)) == 1) { buflen--; if (c == '\n') break; buf[i] = c; i++; } if (r == -1) return (-1); /* * We've filled the buffer, but still haven't seen \n. Keep eating * until we find it; we don't expect this to happen, but this is * defensive. */ if (c != '\n') { while ((r = read(clifd, &c, sizeof (c))) > 0) if (c == '\n') break; } /* * Parse buffer for message of the form: IDENT */ bufp = buf; if (strncmp(bufp, "IDENT ", 6) != 0) return (-1); bufp += 6; errno = 0; *pid = strtoll(bufp, &bufp, 10); if (errno != 0) return (-1); while (*bufp != '\0' && isspace(*bufp)) bufp++; (void) strlcpy(locale, bufp, locale_len); return (0); } static int accept_client(int servfd, pid_t *pid, char *locale, size_t locale_len) { int connfd; struct sockaddr_un cliaddr; socklen_t clilen; clilen = sizeof (cliaddr); connfd = accept(servfd, (struct sockaddr *)&cliaddr, &clilen); if (connfd == -1) return (-1); if (get_client_ident(connfd, pid, locale, locale_len) == -1) { (void) shutdown(connfd, SHUT_RDWR); (void) close(connfd); return (-1); } (void) write(connfd, "OK\n", 3); return (connfd); } static void reject_client(int servfd, pid_t clientpid) { int connfd; struct sockaddr_un cliaddr; socklen_t clilen; char nak[MAXPATHLEN]; clilen = sizeof (cliaddr); connfd = accept(servfd, (struct sockaddr *)&cliaddr, &clilen); /* * After hear its ident string, tell client to get lost. */ if (get_client_ident(connfd, NULL, NULL, 0) == 0) { (void) snprintf(nak, sizeof (nak), "%lu\n", clientpid); (void) write(connfd, nak, strlen(nak)); } (void) shutdown(connfd, SHUT_RDWR); (void) close(connfd); } static void event_message(int clifd, char *clilocale, zone_evt_t evt) { char msg[BUFSIZ]; char *str; const char *fmt; if (clifd == -1) return; switch (evt) { case Z_EVT_ZONE_BOOTING: str = "Zone booting up"; break; case Z_EVT_ZONE_READIED: str = "Zone readied"; break; case Z_EVT_ZONE_HALTED: str = "Zone halted"; break; case Z_EVT_ZONE_REBOOTING: str = "Zone rebooting"; break; case Z_EVT_ZONE_UNINSTALLING: str = "Zone is being uninstalled. Disconnecting..."; break; default: return; } str = localize_msg(clilocale, str); fmt = localize_msg(clilocale, "\r\n[NOTICE: %s]\r\n"); (void) snprintf(msg, sizeof (msg), fmt, str); (void) write(clifd, msg, strlen(msg)); } /* * Check to see if the client at the other end of the socket is still * alive; we know it is not if it throws EPIPE at us when we try to write * an otherwise harmless 0-length message to it. */ static int test_client(int clifd) { if ((write(clifd, "", 0) == -1) && errno == EPIPE) return (-1); return (0); } /* * This routine drives the console I/O loop. It polls for input from the * master side of the console (output to the console), and from the client * (input from the console user). Additionally, it polls on the server fd, * and disconnects any clients that might try to hook up with the zone while * the console is in use. * * When the client first calls us up, it is expected to send a line giving * its "identity"; this consists of the string 'IDENT '. * This is so that we can report that the console is busy along with * some diagnostics about who has it busy; the locale is used so that * asynchronous messages about zone state (like the NOTICE: zone halted * messages) can be output in the user's locale. */ static void do_console_io(zlog_t *zlogp, int consfd, int servfd) { struct pollfd pollfds[4]; char ibuf[BUFSIZ]; int cc, ret; int clifd = -1; int pollerr = 0; char clilocale[MAXPATHLEN]; pid_t clipid = 0; /* console side, watch for read events */ pollfds[0].fd = consfd; pollfds[0].events = POLLIN | POLLRDNORM | POLLRDBAND | POLLPRI | POLLERR | POLLHUP | POLLNVAL; /* client side, watch for read events */ pollfds[1].fd = clifd; pollfds[1].events = pollfds[0].events; /* the server socket; watch for events (new connections) */ pollfds[2].fd = servfd; pollfds[2].events = pollfds[0].events; /* the eventstram; watch for events (e.g.: zone halted) */ pollfds[3].fd = eventstream[1]; pollfds[3].events = pollfds[0].events; for (;;) { pollfds[0].revents = pollfds[1].revents = 0; pollfds[2].revents = pollfds[3].revents = 0; ret = poll(pollfds, sizeof (pollfds) / sizeof (struct pollfd), -1); if (ret == -1 && errno != EINTR) { zerror(zlogp, B_TRUE, "poll failed"); /* we are hosed, close connection */ break; } /* event from console side */ if (pollfds[0].revents) { if (pollfds[0].revents & (POLLIN | POLLRDNORM | POLLRDBAND | POLLPRI)) { errno = 0; cc = read(consfd, ibuf, BUFSIZ); if (cc <= 0 && (errno != EINTR) && (errno != EAGAIN)) break; /* * Lose I/O if no one is listening */ if (clifd != -1 && cc > 0) (void) write(clifd, ibuf, cc); } else { pollerr = pollfds[0].revents; zerror(zlogp, B_FALSE, "closing connection with (console) " "pollerr %d\n", pollerr); break; } } /* event from client side */ if (pollfds[1].revents) { if (pollfds[1].revents & (POLLIN | POLLRDNORM | POLLRDBAND | POLLPRI)) { errno = 0; cc = read(clifd, ibuf, BUFSIZ); if (cc <= 0 && (errno != EINTR) && (errno != EAGAIN)) break; (void) write(consfd, ibuf, cc); } else { pollerr = pollfds[1].revents; zerror(zlogp, B_FALSE, "closing connection with (client) " "pollerr %d\n", pollerr); break; } } /* event from server socket */ if (pollfds[2].revents && (pollfds[2].revents & (POLLIN | POLLRDNORM))) { if (clifd != -1) { /* * Test the client to see if it is really * still alive. If it has died but we * haven't yet detected that, we might * deny a legitimate connect attempt. If it * is dead, we break out; once we tear down * the old connection, the new connection * will happen. */ if (test_client(clifd) == -1) { break; } /* we're already handling a client */ reject_client(servfd, clipid); } else if ((clifd = accept_client(servfd, &clipid, clilocale, sizeof (clilocale))) != -1) { pollfds[1].fd = clifd; } else { break; } } /* * Watch for events on the eventstream. This is how we get * notified of the zone halting, etc. It provides us a * "wakeup" from poll when important things happen, which * is good. */ if (pollfds[3].revents) { int evt = eventstream_read(); /* * After we drain out the event, if we aren't servicing * a console client, we hop back out to our caller, * which will check to see if it is time to shutdown * the daemon, or if we should take another console * service lap. */ if (clifd == -1) { break; } event_message(clifd, clilocale, evt); /* * Special handling for the message that the zone is * uninstalling; we boot the client, then break out * of this function. When we return to the * serve_console loop, we will see that the zone is * in a state < READY, and so zoneadmd will shutdown. */ if (evt == Z_EVT_ZONE_UNINSTALLING) { break; } } } if (clifd != -1) { (void) shutdown(clifd, SHUT_RDWR); (void) close(clifd); } } int init_console(zlog_t *zlogp) { if (init_console_dev(zlogp) == -1) { zerror(zlogp, B_FALSE, "console setup: device initialization failed"); return (-1); } if ((serverfd = init_console_sock(zlogp)) == -1) { zerror(zlogp, B_FALSE, "console setup: socket initialization failed"); return (-1); } return (0); } /* * serve_console() is the master loop for driving console I/O. It is also the * routine which is ultimately responsible for "pulling the plug" on zoneadmd * when it realizes that the daemon should shut down. * * The rules for shutdown are: there must be no console client, and the zone * state must be < ready. However, we need to give things a chance to actually * get going when the daemon starts up-- otherwise the daemon would immediately * exit on startup if the zone was in the installed state, so we first drop * into the do_console_io() loop in order to give *something* a chance to * happen. */ void serve_console(zlog_t *zlogp) { int masterfd; zone_state_t zstate; char conspath[MAXPATHLEN]; (void) snprintf(conspath, sizeof (conspath), "/dev/zcons/%s/%s", zone_name, ZCONS_MASTER_NAME); for (;;) { masterfd = open(conspath, O_RDWR|O_NONBLOCK|O_NOCTTY); if (masterfd == -1) { zerror(zlogp, B_TRUE, "failed to open console master"); (void) mutex_lock(&lock); goto death; } /* * Setting RPROTDIS on the stream means that the control * portion of messages received (which we don't care about) * will be discarded by the stream head. If we allowed such * messages, we wouldn't be able to use read(2), as it fails * (EBADMSG) when a message with a control element is received. */ if (ioctl(masterfd, I_SRDOPT, RNORM|RPROTDIS) == -1) { zerror(zlogp, B_TRUE, "failed to set options on " "console master"); (void) mutex_lock(&lock); goto death; } do_console_io(zlogp, masterfd, serverfd); /* * We would prefer not to do this, but hostile zone processes * can cause the stream to become tainted, and reads will * fail. So, in case something has gone seriously ill, * we dismantle the stream and reopen the console when we * take another lap. */ (void) close(masterfd); (void) mutex_lock(&lock); /* * We need to set death_throes (see below) atomically with * respect to noticing that (a) we have no console client and * (b) the zone is not installed. Otherwise we could get a * request to boot during this time. Once we set death_throes, * any incoming door stuff will be turned away. */ if (zone_get_state(zone_name, &zstate) == Z_OK) { if (zstate < ZONE_STATE_READY) goto death; } else { zerror(zlogp, B_FALSE, "unable to determine state of zone"); goto death; } /* * Even if zone_get_state() fails, stay conservative, and * take another lap. */ (void) mutex_unlock(&lock); } death: assert(MUTEX_HELD(&lock)); in_death_throes = B_TRUE; (void) mutex_unlock(&lock); destroy_console_sock(serverfd); (void) destroy_console_devs(zlogp); }