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Diffstat (limited to 'src/systemd-initctl/initctl.c')
-rw-r--r--src/systemd-initctl/initctl.c428
1 files changed, 428 insertions, 0 deletions
diff --git a/src/systemd-initctl/initctl.c b/src/systemd-initctl/initctl.c
new file mode 100644
index 0000000000..05285e3846
--- /dev/null
+++ b/src/systemd-initctl/initctl.c
@@ -0,0 +1,428 @@
+/***
+ This file is part of systemd.
+
+ Copyright 2010 Lennart Poettering
+
+ systemd is free software; you can redistribute it and/or modify it
+ under the terms of the GNU Lesser General Public License as published by
+ the Free Software Foundation; either version 2.1 of the License, or
+ (at your option) any later version.
+
+ systemd is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public License
+ along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include <ctype.h>
+#include <errno.h>
+#include <stdio.h>
+#include <sys/epoll.h>
+#include <unistd.h>
+
+#include <systemd/sd-bus.h>
+#include <systemd/sd-daemon.h>
+
+#include "alloc-util.h"
+#include "bus-error.h"
+#include "bus-util.h"
+#include "def.h"
+#include "fd-util.h"
+#include "formats-util.h"
+#include "initreq.h"
+#include "list.h"
+#include "log.h"
+#include "special.h"
+#include "util.h"
+
+#define SERVER_FD_MAX 16
+#define TIMEOUT_MSEC ((int) (DEFAULT_EXIT_USEC/USEC_PER_MSEC))
+
+typedef struct Fifo Fifo;
+
+typedef struct Server {
+ int epoll_fd;
+
+ LIST_HEAD(Fifo, fifos);
+ unsigned n_fifos;
+
+ sd_bus *bus;
+
+ bool quit;
+} Server;
+
+struct Fifo {
+ Server *server;
+
+ int fd;
+
+ struct init_request buffer;
+ size_t bytes_read;
+
+ LIST_FIELDS(Fifo, fifo);
+};
+
+static const char *translate_runlevel(int runlevel, bool *isolate) {
+ static const struct {
+ const int runlevel;
+ const char *special;
+ bool isolate;
+ } table[] = {
+ { '0', SPECIAL_POWEROFF_TARGET, false },
+ { '1', SPECIAL_RESCUE_TARGET, true },
+ { 's', SPECIAL_RESCUE_TARGET, true },
+ { 'S', SPECIAL_RESCUE_TARGET, true },
+ { '2', SPECIAL_MULTI_USER_TARGET, true },
+ { '3', SPECIAL_MULTI_USER_TARGET, true },
+ { '4', SPECIAL_MULTI_USER_TARGET, true },
+ { '5', SPECIAL_GRAPHICAL_TARGET, true },
+ { '6', SPECIAL_REBOOT_TARGET, false },
+ };
+
+ unsigned i;
+
+ assert(isolate);
+
+ for (i = 0; i < ELEMENTSOF(table); i++)
+ if (table[i].runlevel == runlevel) {
+ *isolate = table[i].isolate;
+ if (runlevel == '6' && kexec_loaded())
+ return SPECIAL_KEXEC_TARGET;
+ return table[i].special;
+ }
+
+ return NULL;
+}
+
+static void change_runlevel(Server *s, int runlevel) {
+ const char *target;
+ _cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL;
+ const char *mode;
+ bool isolate = false;
+ int r;
+
+ assert(s);
+
+ target = translate_runlevel(runlevel, &isolate);
+ if (!target) {
+ log_warning("Got request for unknown runlevel %c, ignoring.", runlevel);
+ return;
+ }
+
+ if (isolate)
+ mode = "isolate";
+ else
+ mode = "replace-irreversibly";
+
+ log_debug("Running request %s/start/%s", target, mode);
+
+ r = sd_bus_call_method(
+ s->bus,
+ "org.freedesktop.systemd1",
+ "/org/freedesktop/systemd1",
+ "org.freedesktop.systemd1.Manager",
+ "StartUnit",
+ &error,
+ NULL,
+ "ss", target, mode);
+ if (r < 0) {
+ log_error("Failed to change runlevel: %s", bus_error_message(&error, -r));
+ return;
+ }
+}
+
+static void request_process(Server *s, const struct init_request *req) {
+ assert(s);
+ assert(req);
+
+ if (req->magic != INIT_MAGIC) {
+ log_error("Got initctl request with invalid magic. Ignoring.");
+ return;
+ }
+
+ switch (req->cmd) {
+
+ case INIT_CMD_RUNLVL:
+ if (!isprint(req->runlevel))
+ log_error("Got invalid runlevel. Ignoring.");
+ else
+ switch (req->runlevel) {
+
+ /* we are async anyway, so just use kill for reexec/reload */
+ case 'u':
+ case 'U':
+ if (kill(1, SIGTERM) < 0)
+ log_error_errno(errno, "kill() failed: %m");
+
+ /* The bus connection will be
+ * terminated if PID 1 is reexecuted,
+ * hence let's just exit here, and
+ * rely on that we'll be restarted on
+ * the next request */
+ s->quit = true;
+ break;
+
+ case 'q':
+ case 'Q':
+ if (kill(1, SIGHUP) < 0)
+ log_error_errno(errno, "kill() failed: %m");
+ break;
+
+ default:
+ change_runlevel(s, req->runlevel);
+ }
+ return;
+
+ case INIT_CMD_POWERFAIL:
+ case INIT_CMD_POWERFAILNOW:
+ case INIT_CMD_POWEROK:
+ log_warning("Received UPS/power initctl request. This is not implemented in systemd. Upgrade your UPS daemon!");
+ return;
+
+ case INIT_CMD_CHANGECONS:
+ log_warning("Received console change initctl request. This is not implemented in systemd.");
+ return;
+
+ case INIT_CMD_SETENV:
+ case INIT_CMD_UNSETENV:
+ log_warning("Received environment initctl request. This is not implemented in systemd.");
+ return;
+
+ default:
+ log_warning("Received unknown initctl request. Ignoring.");
+ return;
+ }
+}
+
+static int fifo_process(Fifo *f) {
+ ssize_t l;
+
+ assert(f);
+
+ errno = EIO;
+ l = read(f->fd,
+ ((uint8_t*) &f->buffer) + f->bytes_read,
+ sizeof(f->buffer) - f->bytes_read);
+ if (l <= 0) {
+ if (errno == EAGAIN)
+ return 0;
+
+ return log_warning_errno(errno, "Failed to read from fifo: %m");
+ }
+
+ f->bytes_read += l;
+ assert(f->bytes_read <= sizeof(f->buffer));
+
+ if (f->bytes_read == sizeof(f->buffer)) {
+ request_process(f->server, &f->buffer);
+ f->bytes_read = 0;
+ }
+
+ return 0;
+}
+
+static void fifo_free(Fifo *f) {
+ assert(f);
+
+ if (f->server) {
+ assert(f->server->n_fifos > 0);
+ f->server->n_fifos--;
+ LIST_REMOVE(fifo, f->server->fifos, f);
+ }
+
+ if (f->fd >= 0) {
+ if (f->server)
+ epoll_ctl(f->server->epoll_fd, EPOLL_CTL_DEL, f->fd, NULL);
+
+ safe_close(f->fd);
+ }
+
+ free(f);
+}
+
+static void server_done(Server *s) {
+ assert(s);
+
+ while (s->fifos)
+ fifo_free(s->fifos);
+
+ safe_close(s->epoll_fd);
+
+ if (s->bus) {
+ sd_bus_flush(s->bus);
+ sd_bus_unref(s->bus);
+ }
+}
+
+static int server_init(Server *s, unsigned n_sockets) {
+ int r;
+ unsigned i;
+
+ assert(s);
+ assert(n_sockets > 0);
+
+ zero(*s);
+
+ s->epoll_fd = epoll_create1(EPOLL_CLOEXEC);
+ if (s->epoll_fd < 0) {
+ r = log_error_errno(errno,
+ "Failed to create epoll object: %m");
+ goto fail;
+ }
+
+ for (i = 0; i < n_sockets; i++) {
+ struct epoll_event ev;
+ Fifo *f;
+ int fd;
+
+ fd = SD_LISTEN_FDS_START+i;
+
+ r = sd_is_fifo(fd, NULL);
+ if (r < 0) {
+ log_error_errno(r, "Failed to determine file descriptor type: %m");
+ goto fail;
+ }
+
+ if (!r) {
+ log_error("Wrong file descriptor type.");
+ r = -EINVAL;
+ goto fail;
+ }
+
+ f = new0(Fifo, 1);
+ if (!f) {
+ r = -ENOMEM;
+ log_error_errno(errno, "Failed to create fifo object: %m");
+ goto fail;
+ }
+
+ f->fd = -1;
+
+ zero(ev);
+ ev.events = EPOLLIN;
+ ev.data.ptr = f;
+ if (epoll_ctl(s->epoll_fd, EPOLL_CTL_ADD, fd, &ev) < 0) {
+ r = -errno;
+ fifo_free(f);
+ log_error_errno(errno, "Failed to add fifo fd to epoll object: %m");
+ goto fail;
+ }
+
+ f->fd = fd;
+ LIST_PREPEND(fifo, s->fifos, f);
+ f->server = s;
+ s->n_fifos++;
+ }
+
+ r = bus_connect_system_systemd(&s->bus);
+ if (r < 0) {
+ log_error_errno(r, "Failed to get D-Bus connection: %m");
+ r = -EIO;
+ goto fail;
+ }
+
+ return 0;
+
+fail:
+ server_done(s);
+
+ return r;
+}
+
+static int process_event(Server *s, struct epoll_event *ev) {
+ int r;
+ Fifo *f;
+
+ assert(s);
+
+ if (!(ev->events & EPOLLIN)) {
+ log_info("Got invalid event from epoll. (3)");
+ return -EIO;
+ }
+
+ f = (Fifo*) ev->data.ptr;
+ r = fifo_process(f);
+ if (r < 0) {
+ log_info_errno(r, "Got error on fifo: %m");
+ fifo_free(f);
+ return r;
+ }
+
+ return 0;
+}
+
+int main(int argc, char *argv[]) {
+ Server server;
+ int r = EXIT_FAILURE, n;
+
+ if (getppid() != 1) {
+ log_error("This program should be invoked by init only.");
+ return EXIT_FAILURE;
+ }
+
+ if (argc > 1) {
+ log_error("This program does not take arguments.");
+ return EXIT_FAILURE;
+ }
+
+ log_set_target(LOG_TARGET_AUTO);
+ log_parse_environment();
+ log_open();
+
+ umask(0022);
+
+ n = sd_listen_fds(true);
+ if (n < 0) {
+ log_error_errno(r, "Failed to read listening file descriptors from environment: %m");
+ return EXIT_FAILURE;
+ }
+
+ if (n <= 0 || n > SERVER_FD_MAX) {
+ log_error("No or too many file descriptors passed.");
+ return EXIT_FAILURE;
+ }
+
+ if (server_init(&server, (unsigned) n) < 0)
+ return EXIT_FAILURE;
+
+ log_debug("systemd-initctl running as pid "PID_FMT, getpid());
+
+ sd_notify(false,
+ "READY=1\n"
+ "STATUS=Processing requests...");
+
+ while (!server.quit) {
+ struct epoll_event event;
+ int k;
+
+ k = epoll_wait(server.epoll_fd, &event, 1, TIMEOUT_MSEC);
+ if (k < 0) {
+ if (errno == EINTR)
+ continue;
+ log_error_errno(errno, "epoll_wait() failed: %m");
+ goto fail;
+ }
+
+ if (k <= 0)
+ break;
+
+ if (process_event(&server, &event) < 0)
+ goto fail;
+ }
+
+ r = EXIT_SUCCESS;
+
+ log_debug("systemd-initctl stopped as pid "PID_FMT, getpid());
+
+fail:
+ sd_notify(false,
+ "STOPPING=1\n"
+ "STATUS=Shutting down...");
+
+ server_done(&server);
+
+ return r;
+}
generated by cgit v1.2.3-54-g00ecf (git 2.45.2) at 2024-11-05 21:29:25 +0000