Commit 0b7964b8 authored by Lennart Poettering's avatar Lennart Poettering
Browse files

sysv: implement /dev/initctl compatibility

parent 0fd030be
systemd-cgroups-agent
systemd-initctl
systemd
*.o
test-engine
......
......@@ -37,7 +37,8 @@ bin_PROGRAMS = \
pkglibexec_PROGRAMS = \
systemd-logger \
systemd-cgroups-agent
systemd-cgroups-agent \
systemd-initctl
noinst_PROGRAMS = \
test-engine \
......@@ -137,6 +138,17 @@ systemd_logger_SOURCES = \
$(BASIC_SOURCES) \
logger.c
systemd_initctl_SOURCES = \
$(BASIC_SOURCES) \
initctl.c
systemd_initctl_CPPFLAGS = \
$(AM_CPPFLAGS) \
$(DBUS_CFLAGS)
systemd_initctl_LDADD = \
$(DBUS_LIBS)
systemd_cgroups_agent_SOURCES = \
$(BASIC_SOURCES) \
cgroups-agent.c
......
/*-*- Mode: C; c-basic-offset: 8 -*-*/
/***
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 General Public License as published by
the Free Software Foundation; either version 2 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
General Public License for more details.
You should have received a copy of the GNU General Public License
along with systemd; If not, see <http://www.gnu.org/licenses/>.
***/
#include <sys/socket.h>
#include <sys/types.h>
#include <assert.h>
#include <time.h>
#include <string.h>
#include <stdio.h>
#include <errno.h>
#include <unistd.h>
#include <sys/poll.h>
#include <sys/epoll.h>
#include <sys/un.h>
#include <fcntl.h>
#include <ctype.h>
#include <dbus/dbus.h>
#include "util.h"
#include "log.h"
#include "list.h"
#include "initreq.h"
#define SERVER_FD_START 3
#define SERVER_FD_MAX 16
#define TIMEOUT ((int) (10*MSEC_PER_SEC))
typedef struct Fifo Fifo;
typedef struct Server {
int epoll_fd;
LIST_HEAD(Fifo, fifos);
unsigned n_fifos;
DBusConnection *bus;
} 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) {
switch (runlevel) {
case '0':
return "halt.target";
case '1':
case 's':
case 'S':
return "rescue.target";
case '2':
return "runlevel2.target";
case '3':
return "runlevel3.target";
case '4':
return "runlevel4.target";
case '5':
return "runlevel5.target";
case '6':
return "reboot.target";
default:
return NULL;
}
}
static void change_runlevel(Server *s, int runlevel) {
const char *target;
DBusMessage *m = NULL, *reply = NULL;
DBusError error;
const char *path, *replace = "replace";
assert(s);
dbus_error_init(&error);
if (!(target = translate_runlevel(runlevel))) {
log_warning("Got request for unknown runlevel %c, ignoring.", runlevel);
goto finish;
}
log_debug("Running request %s", target);
if (!(m = dbus_message_new_method_call("org.freedesktop.systemd1", "/org/freedesktop/systemd1", "org.freedesktop.systemd1", "GetUnit"))) {
log_error("Could not allocate message.");
goto finish;
}
if (!dbus_message_append_args(m,
DBUS_TYPE_STRING, &target,
DBUS_TYPE_INVALID)) {
log_error("Could not attach group information to signal message.");
goto finish;
}
if (!(reply = dbus_connection_send_with_reply_and_block(s->bus, m, -1, &error))) {
log_error("Failed to get unit path: %s", error.message);
goto finish;
}
if (!dbus_message_get_args(reply, &error,
DBUS_TYPE_OBJECT_PATH, &path,
DBUS_TYPE_INVALID)) {
log_error("Failed to parse unit path: %s", error.message);
goto finish;
}
dbus_message_unref(m);
if (!(m = dbus_message_new_method_call("org.freedesktop.systemd1", path, "org.freedesktop.systemd1.Unit", "Start"))) {
log_error("Could not allocate message.");
goto finish;
}
if (!dbus_message_append_args(m,
DBUS_TYPE_STRING, &replace,
DBUS_TYPE_INVALID)) {
log_error("Could not attach group information to signal message.");
goto finish;
}
dbus_message_unref(reply);
if (!(reply = dbus_connection_send_with_reply_and_block(s->bus, m, -1, &error))) {
log_error("Failed to start unit: %s", error.message);
goto finish;
}
finish:
if (m)
dbus_message_unref(m);
if (reply)
dbus_message_unref(reply);
dbus_error_free(&error);
}
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
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;
if ((l = read(f->fd, ((uint8_t*) &f->buffer) + f->bytes_read, sizeof(f->buffer) - f->bytes_read)) <= 0) {
if (errno == EAGAIN)
return 0;
log_warning("Failed to read from fifo: %s", strerror(errno));
return -1;
}
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, fifo, f->server->fifos, f);
}
if (f->fd >= 0) {
if (f->server)
epoll_ctl(f->server->epoll_fd, EPOLL_CTL_DEL, f->fd, NULL);
assert_se(close_nointr(f->fd) == 0);
}
free(f);
}
static int verify_environment(unsigned *n_sockets) {
unsigned long long pid;
const char *e;
int r;
unsigned ns;
assert_se(n_sockets);
if (!(e = getenv("LISTEN_PID"))) {
log_error("Missing $LISTEN_PID environment variable.");
return -ENOENT;
}
if ((r = safe_atollu(e, &pid)) < 0) {
log_error("Failed to parse $LISTEN_PID: %s", strerror(-r));
return r;
}
if (pid != (unsigned long long) getpid()) {
log_error("Socket nor for me.");
return -ENOENT;
}
if (!(e = getenv("LISTEN_FDS"))) {
log_error("Missing $LISTEN_FDS environment variable.");
return -ENOENT;
}
if ((r = safe_atou(e, &ns)) < 0) {
log_error("Failed to parse $LISTEN_FDS: %s", strerror(-r));
return -E2BIG;
}
if (ns <= 0 || ns > SERVER_FD_MAX) {
log_error("Wrong number of file descriptors passed: %s", e);
return -E2BIG;
}
*n_sockets = ns;
return 0;
}
static void server_done(Server *s) {
assert(s);
while (s->fifos)
fifo_free(s->fifos);
if (s->epoll_fd >= 0)
assert_se(close_nointr(s->epoll_fd) == 0);
if (s->bus)
dbus_connection_unref(s->bus);
}
static int server_init(Server *s, unsigned n_sockets) {
int r;
unsigned i;
DBusError error;
assert(s);
assert(n_sockets > 0);
dbus_error_init(&error);
zero(*s);
if ((s->epoll_fd = epoll_create1(EPOLL_CLOEXEC)) < 0) {
r = -errno;
log_error("Failed to create epoll object: %s", strerror(errno));
goto fail;
}
for (i = 0; i < n_sockets; i++) {
struct epoll_event ev;
Fifo *f;
if (!(f = new0(Fifo, 1))) {
r = -ENOMEM;
log_error("Failed to create fifo object: %s", strerror(errno));
goto fail;
}
f->fd = -1;
zero(ev);
ev.events = EPOLLIN;
ev.data.ptr = f;
if (epoll_ctl(s->epoll_fd, EPOLL_CTL_ADD, SERVER_FD_START+i, &ev) < 0) {
r = -errno;
fifo_free(f);
log_error("Failed to add fifo fd to epoll object: %s", strerror(errno));
goto fail;
}
f->fd = SERVER_FD_START+i;
LIST_PREPEND(Fifo, fifo, s->fifos, f);
f->server = s;
s->n_fifos ++;
}
if (!(s->bus = dbus_bus_get(DBUS_BUS_SYSTEM, &error))) {
log_error("Failed to get D-Bus connection: %s", error.message);
goto fail;
}
return 0;
fail:
server_done(s);
dbus_error_free(&error);
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;
if ((r = fifo_process(f)) < 0) {
log_info("Got error on fifo: %s", strerror(-r));
fifo_free(f);
return r;
}
return 0;
}
int main(int argc, char *argv[]) {
Server server;
int r = 3;
unsigned n;
log_info("systemd-initctl running as pid %llu", (unsigned long long) getpid());
if (verify_environment(&n) < 0)
return 1;
if (server_init(&server, n) < 0)
return 2;
for (;;) {
struct epoll_event event;
int k;
if ((k = epoll_wait(server.epoll_fd,
&event, 1,
TIMEOUT)) < 0) {
if (errno == EINTR)
continue;
log_error("epoll_wait() failed: %s", strerror(errno));
goto fail;
}
if (k <= 0)
break;
if ((k = process_event(&server, &event)) < 0)
goto fail;
}
r = 0;
fail:
server_done(&server);
log_info("systemd-initctl stopped as pid %llu", (unsigned long long) getpid());
dbus_shutdown();
return r;
}
/*
* initreq.h Interface to talk to init through /dev/initctl.
*
* Copyright (C) 1995-2004 Miquel van Smoorenburg
*
* This library 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 of the License, or (at your option) any later version.
*
* Version: @(#)initreq.h 1.28 31-Mar-2004 MvS
*
*/
#ifndef _INITREQ_H
#define _INITREQ_H
#include <sys/param.h>
#if defined(__FreeBSD_kernel__)
# define INIT_FIFO "/etc/.initctl"
#else
# define INIT_FIFO "/dev/initctl"
#endif
#define INIT_MAGIC 0x03091969
#define INIT_CMD_START 0
#define INIT_CMD_RUNLVL 1
#define INIT_CMD_POWERFAIL 2
#define INIT_CMD_POWERFAILNOW 3
#define INIT_CMD_POWEROK 4
#define INIT_CMD_BSD 5
#define INIT_CMD_SETENV 6
#define INIT_CMD_UNSETENV 7
#define INIT_CMD_CHANGECONS 12345
#ifdef MAXHOSTNAMELEN
# define INITRQ_HLEN MAXHOSTNAMELEN
#else
# define INITRQ_HLEN 64
#endif
/*
* This is what BSD 4.4 uses when talking to init.
* Linux doesn't use this right now.
*/
struct init_request_bsd {
char gen_id[8]; /* Beats me.. telnetd uses "fe" */
char tty_id[16]; /* Tty name minus /dev/tty */
char host[INITRQ_HLEN]; /* Hostname */
char term_type[16]; /* Terminal type */
int signal; /* Signal to send */
int pid; /* Process to send to */
char exec_name[128]; /* Program to execute */
char reserved[128]; /* For future expansion. */
};
/*
* Because of legacy interfaces, "runlevel" and "sleeptime"
* aren't in a seperate struct in the union.
*
* The weird sizes are because init expects the whole
* struct to be 384 bytes.
*/
struct init_request {
int magic; /* Magic number */
int cmd; /* What kind of request */
int runlevel; /* Runlevel to change to */
int sleeptime; /* Time between TERM and KILL */
union {
struct init_request_bsd bsd;
char data[368];
} i;
};
#endif
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