[mirror_lxc.git] / src / lxc / start.c

/*
 * lxc: linux Container library
 *
 * (C) Copyright IBM Corp. 2007, 2008
 *
 * Authors:
 * Daniel Lezcano <dlezcano at fr.ibm.com>
 *
 * 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 2.1 of the License, or (at your option) any later version.
 *
 * This library 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 this library; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 */

#define _GNU_SOURCE
#include <stdio.h>
#undef _GNU_SOURCE
#include <string.h>
#include <stdlib.h>
#include <dirent.h>
#include <errno.h>
#include <unistd.h>
#include <signal.h>
#include <fcntl.h>
#include <termios.h>
#include <sys/param.h>
#include <sys/file.h>
#include <sys/mount.h>
#include <sys/types.h>
#include <sys/prctl.h>
#include <sys/capability.h>
#include <sys/wait.h>
#include <sys/un.h>
#include <sys/poll.h>
#include <sys/signalfd.h>

#include "error.h"
#include "af_unix.h"
#include "mainloop.h"

#include <lxc/lxc.h>

LXC_TTY_HANDLER(SIGINT);
LXC_TTY_HANDLER(SIGQUIT);

static int setup_sigchld_fd(sigset_t *oldmask)
{
	sigset_t mask;
	int fd;

	if (sigprocmask(SIG_BLOCK, NULL, &mask)) {
		lxc_log_syserror("failed to get mask signal");
		return -1;
	}

	if (sigaddset(&mask, SIGCHLD) || sigprocmask(SIG_BLOCK, &mask, oldmask)) {
		lxc_log_syserror("failed to set mask signal");
		return -1;
	}

	fd = signalfd(-1, &mask, 0);
	if (fd < 0) {
		lxc_log_syserror("failed to create the signal fd");
		return -1;
	}

	if (fcntl(fd, F_SETFD, FD_CLOEXEC)) {
		lxc_log_syserror("failed to set sigfd to close-on-exec");
		close(fd);
		return -1;
	}

	return fd;
}

static int setup_tty_service(const char *name, int *ttyfd)
{
	int fd;
	struct sockaddr_un addr = { 0 };
	char *offset = &addr.sun_path[1];
	
	strcpy(offset, name);
	addr.sun_path[0] = '\0';

	fd = lxc_af_unix_open(addr.sun_path, SOCK_STREAM, 0);
	if (fd < 0)
		return -1;

	if (fcntl(fd, F_SETFD, FD_CLOEXEC)) {
		lxc_log_syserror("failed to close-on-exec flag");
		close(fd);
		return -1;
	}

	*ttyfd = fd;

	return 0;
}

static int sigchld_handler(int fd, void *data, 
			   struct lxc_epoll_descr *descr)
{
	pid_t *pid = data;

	waitpid(*pid, NULL, 0);

	return 1;
}

static int ttyclient_handler(int fd, void *data,
			     struct lxc_epoll_descr *descr)
{
	int i;
 	struct lxc_tty_info *tty_info = data;

	for (i = 0; i < tty_info->nbtty; i++) {

		if (tty_info->pty_info[i].busy != fd)
			continue;

		lxc_mainloop_del_handler(descr, fd);
		tty_info->pty_info[i].busy = 0;
		close(fd);
	}

	return 0;
}

static int ttyservice_handler(int fd, void *data,
			      struct lxc_epoll_descr *descr)
{
	int conn, ttynum, val = 1, ret = -1;
	struct lxc_tty_info *tty_info = data;
	
	conn = accept(fd, NULL, 0);
	if (conn < 0) {
		lxc_log_syserror("failed to accept tty client");
		return -1;
	}
	
	if (setsockopt(conn, SOL_SOCKET, SO_PASSCRED, &val, sizeof(val))) {
		lxc_log_syserror("failed to enable credential on socket");
		goto out_close;
	}

	if (lxc_af_unix_rcv_credential(conn, &ttynum, sizeof(ttynum)))
		goto out_close;

	if (ttynum <= 0 || ttynum > tty_info->nbtty)
		goto out_close;

	/* fixup index array (eg. tty1 is index 0) */
	ttynum--;

	if (tty_info->pty_info[ttynum].busy)
		goto out_close;

	if (lxc_af_unix_send_fd(conn, tty_info->pty_info[ttynum].master, 
				NULL, 0) < 0) {
		lxc_log_error("failed to send tty to client");
		goto out_close;
	}

	if (lxc_mainloop_add_handler(descr, conn, 
				     ttyclient_handler, tty_info)) {
		lxc_log_error("failed to add tty client handler");
		goto out_close;
	}

	tty_info->pty_info[ttynum].busy = conn;

	ret = 0;

out:
	return ret;
out_close:
	close(conn);
	goto out;
}

static int mainloop(const char *name, pid_t pid, int sigfd,
		    const struct lxc_tty_info *tty_info)
{
	int nfds, ttyfd = -1, ret = -1;
	struct lxc_epoll_descr descr;

	if (tty_info->nbtty && setup_tty_service(name, &ttyfd)) {
		lxc_log_error("failed to create the tty service point");
		goto out_sigfd;
	}

	/* sigfd + nb tty + tty service 
	 * if tty is enabled */
	nfds = tty_info->nbtty + 1 + tty_info->nbtty ? 1 : 0;

	if (lxc_mainloop_open(nfds, &descr)) {
		lxc_log_error("failed to create mainloop");
		goto out_ttyfd;
	}

	if (lxc_mainloop_add_handler(&descr, sigfd, sigchld_handler, &pid)) {
		lxc_log_error("failed to add handler for the signal");
		goto out_mainloop_open;
	}

	if (tty_info->nbtty) {
		if (lxc_mainloop_add_handler(&descr, ttyfd, 
					     ttyservice_handler, 
					     (void *)tty_info)) {
			lxc_log_error("failed to add handler for the tty");
			goto out_mainloop_open;
		}
	}

	ret = lxc_mainloop(&descr);

out:
	return ret;

out_mainloop_open:
	lxc_mainloop_close(&descr);
out_ttyfd:
	close(ttyfd);
out_sigfd:
	close(sigfd);
	goto out;
}

int lxc_start(const char *name, char *argv[])
{
	struct lxc_tty_info tty_info = { 0 };
	sigset_t oldmask;
	char init[MAXPATHLEN];
	char tty[MAXPATHLEN];
	char *val = NULL;
	int fd, sigfd, lock, sv[2], sync = 0, err = -LXC_ERROR_INTERNAL;
	pid_t pid;
	int clone_flags;

	lock = lxc_get_lock(name);
	if (lock < 0)
		return lock;

	/* Begin the set the state to STARTING*/
	if (lxc_setstate(name, STARTING)) {
		lxc_log_error("failed to set state '%s'", 
			      lxc_state2str(STARTING));
		goto out;
	}

	/* If we are not attached to a tty, disable it */
	if (ttyname_r(0, tty, sizeof(tty))) 
		tty[0] = '\0';

	if (lxc_create_tty(name, &tty_info)) {
		lxc_log_error("failed to create the ttys");
		goto out;
	}

	/* the signal fd has to be created before forking otherwise
	 * if the child process exits before we setup the signal fd,
	 * the event will be lost and the command will be stuck */
	sigfd = setup_sigchld_fd(&oldmask);
	if (sigfd < 0) {
		lxc_log_error("failed to set sigchild fd handler");
		return -1;
	}

	/* Synchro socketpair */
	if (socketpair(AF_LOCAL, SOCK_STREAM, 0, sv)) {
		lxc_log_syserror("failed to create communication socketpair");
		goto out;
	}

	/* Avoid signals from terminal */
	LXC_TTY_ADD_HANDLER(SIGINT);
	LXC_TTY_ADD_HANDLER(SIGQUIT);

	clone_flags = CLONE_NEWPID|CLONE_NEWIPC|CLONE_NEWNS;
	if (conf_has_utsname(name))
		clone_flags |= CLONE_NEWUTS;
	if (conf_has_network(name))
		clone_flags |= CLONE_NEWNET;

	/* Create a process in a new set of namespaces */
	pid = fork_ns(clone_flags);
	if (pid < 0) {
		lxc_log_syserror("failed to fork into a new namespace");
		goto err_fork_ns;
	}

	if (!pid) {

		if (sigprocmask(SIG_SETMASK, &oldmask, NULL)) {
			lxc_log_syserror("failed to set sigprocmask");
			return -1;
		}

		close(sv[1]);

		/* Be sure we don't inherit this after the exec */
		fcntl(sv[0], F_SETFD, FD_CLOEXEC);
		
		/* Tell our father he can begin to configure the container */
		if (write(sv[0], &sync, sizeof(sync)) < 0) {
			lxc_log_syserror("failed to write socket");
			goto out_child;
		}

		/* Wait for the father to finish the configuration */
		if (read(sv[0], &sync, sizeof(sync)) < 0) {
			lxc_log_syserror("failed to read socket");
			goto out_child;
		}

		/* Setup the container, ip, names, utsname, ... */
		err = lxc_setup(name, tty, &tty_info);
		if (err) {
			lxc_log_error("failed to setup the container");
			if (write(sv[0], &err, sizeof(err)) < 0)
				lxc_log_syserror("failed to write the socket");
			goto out_child;
		}

		if (prctl(PR_CAPBSET_DROP, CAP_SYS_BOOT, 0, 0, 0)) {
			lxc_log_syserror("failed to remove CAP_SYS_BOOT capability");
			goto out_child;
		}

		execvp(argv[0], argv);
		lxc_log_syserror("failed to exec %s", argv[0]);

		err = LXC_ERROR_WRONG_COMMAND;
		/* If the exec fails, tell that to our father */
		if (write(sv[0], &err, sizeof(err)) < 0)
			lxc_log_syserror("failed to write the socket");
		
	out_child:
		exit(err);
	}

	close(sv[0]);
	
	/* Wait for the child to be ready */
	if (read(sv[1], &sync, sizeof(sync)) < 0) {
		lxc_log_syserror("failed to read the socket");
		goto err_pipe_read;
	}

	if (lxc_link_nsgroup(name, pid))
		lxc_log_warning("cgroupfs not found: cgroup disabled");

	/* Create the network configuration */
	if (clone_flags & CLONE_NEWNET && conf_create_network(name, pid)) {
		lxc_log_error("failed to create the configured network");
		goto err_create_network;
	}

	/* Tell the child to continue its initialization */
	if (write(sv[1], &sync, sizeof(sync)) < 0) {
		lxc_log_syserror("failed to write the socket");
		goto err_pipe_write;
	}

	/* Wait for the child to exec or returning an error */
	err = read(sv[1], &sync, sizeof(sync));
	if (err < 0) {
		lxc_log_error("failed to read the socket");
		goto err_pipe_read2;
	}

	if (err > 0) {
		err = sync;
		waitpid(pid, NULL, 0);
		goto err_child_failed;
	}

	asprintf(&val, "%d\n", pid);

	snprintf(init, MAXPATHLEN, LXCPATH "/%s/init", name);

	fd = open(init, O_WRONLY|O_CREAT|O_TRUNC, S_IRUSR|S_IWUSR);
	if (fd < 0) {
		lxc_log_syserror("failed to open '%s'", init);
		goto err_write;
	}
	
	if (write(fd, val, strlen(val)) < 0) {
		lxc_log_syserror("failed to write the init pid");
		goto err_write;
	}

	close(fd);

	if (lxc_setstate(name, RUNNING)) {
		lxc_log_error("failed to set state to %s", 
			      lxc_state2str(RUNNING));
		goto err_state_failed;
	}

	if (mainloop(name, pid, sigfd, &tty_info)) {
		lxc_log_error("mainloop exited with an error");
		goto err_mailoop_failed;
	}

	if (lxc_setstate(name, STOPPING))
		lxc_log_error("failed to set state %s", lxc_state2str(STOPPING));

	if (clone_flags & CLONE_NEWNET && conf_destroy_network(name))
		lxc_log_error("failed to destroy the network");

	err = 0;
out:
	if (lxc_setstate(name, STOPPED))
		lxc_log_error("failed to set state %s", lxc_state2str(STOPPED));

	lxc_delete_tty(&tty_info);
	lxc_unlink_nsgroup(name);
	unlink(init);
	free(val);
	lxc_put_lock(lock);
	LXC_TTY_DEL_HANDLER(SIGQUIT);
	LXC_TTY_DEL_HANDLER(SIGINT);

	return err;

err_write:
	close(fd);

err_state_failed:
err_child_failed:
err_pipe_read2:
err_pipe_write:
	if (clone_flags & CLONE_NEWNET)
		conf_destroy_network(name);
err_create_network:
err_pipe_read:
err_mailoop_failed:
	if (lxc_setstate(name, ABORTING))
		lxc_log_error("failed to set state %s", lxc_state2str(STOPPED));

	kill(pid, SIGKILL);
err_fork_ns:
	close(sv[0]);
	close(sv[1]);
	goto out;
}
Commit	Line	Data
0ad19a3f	1	/*
	2	* lxc: linux Container library
	3	*
	4	* (C) Copyright IBM Corp. 2007, 2008
	5	*
	6	* Authors:
	7	* Daniel Lezcano <dlezcano at fr.ibm.com>
	8	*
	9	* This library is free software; you can redistribute it and/or
	10	* modify it under the terms of the GNU Lesser General Public
	11	* License as published by the Free Software Foundation; either
	12	* version 2.1 of the License, or (at your option) any later version.
	13	*
	14	* This library is distributed in the hope that it will be useful,
	15	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	16	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	17	* Lesser General Public License for more details.
	18	*
	19	* You should have received a copy of the GNU Lesser General Public
	20	* License along with this library; if not, write to the Free Software
	21	* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
	22	*/
	23
	24	#define _GNU_SOURCE
	25	#include <stdio.h>
	26	#undef _GNU_SOURCE
	27	#include <string.h>
	28	#include <stdlib.h>
	29	#include <dirent.h>
	30	#include <errno.h>
	31	#include <unistd.h>
	32	#include <signal.h>
b0a33c1e	33	#include <fcntl.h>
b0a33c1e	34	#include <termios.h>
0ad19a3f	35	#include <sys/param.h>
0ad19a3f	36	#include <sys/file.h>
f4d507d5	37	#include <sys/mount.h>
0ad19a3f	38	#include <sys/types.h>
0ad19a3f	39	#include <sys/prctl.h>
42ff343d	40	#include <sys/capability.h>
0ad19a3f	41	#include <sys/wait.h>
b0a33c1e	42	#include <sys/un.h>
	43	#include <sys/poll.h>
	44	#include <sys/signalfd.h>
0ad19a3f	45
e2bcd7db	46	#include "error.h"
b0a33c1e	47	#include "af_unix.h"
b0a33c1e	48	#include "mainloop.h"
e2bcd7db	49
b113348e	50	#include <lxc/lxc.h>
0ad19a3f	51
	52	LXC_TTY_HANDLER(SIGINT);
	53	LXC_TTY_HANDLER(SIGQUIT);
	54
b0a33c1e	55	static int setup_sigchld_fd(sigset_t *oldmask)
	56	{
	57	sigset_t mask;
	58	int fd;
	59
	60	if (sigprocmask(SIG_BLOCK, NULL, &mask)) {
	61	lxc_log_syserror("failed to get mask signal");
	62	return -1;
	63	}
	64
	65	if (sigaddset(&mask, SIGCHLD) \|\| sigprocmask(SIG_BLOCK, &mask, oldmask)) {
	66	lxc_log_syserror("failed to set mask signal");
	67	return -1;
	68	}
	69
	70	fd = signalfd(-1, &mask, 0);
	71	if (fd < 0) {
	72	lxc_log_syserror("failed to create the signal fd");
	73	return -1;
	74	}
	75
	76	if (fcntl(fd, F_SETFD, FD_CLOEXEC)) {
	77	lxc_log_syserror("failed to set sigfd to close-on-exec");
	78	close(fd);
	79	return -1;
	80	}
	81
	82	return fd;
	83	}
	84
	85	static int setup_tty_service(const char name, int ttyfd)
	86	{
	87	int fd;
	88	struct sockaddr_un addr = { 0 };
	89	char *offset = &addr.sun_path[1];
	90
	91	strcpy(offset, name);
	92	addr.sun_path[0] = '\0';
	93
	94	fd = lxc_af_unix_open(addr.sun_path, SOCK_STREAM, 0);
	95	if (fd < 0)
	96	return -1;
	97
	98	if (fcntl(fd, F_SETFD, FD_CLOEXEC)) {
	99	lxc_log_syserror("failed to close-on-exec flag");
	100	close(fd);
	101	return -1;
	102	}
	103
	104	*ttyfd = fd;
	105
	106	return 0;
	107	}
	108
	109	static int sigchld_handler(int fd, void *data,
	110	struct lxc_epoll_descr *descr)
	111	{
	112	pid_t *pid = data;
	113
	114	waitpid(*pid, NULL, 0);
	115
	116	return 1;
	117	}
	118
119	static int ttyclient_handler(int fd, void *data,
120	struct lxc_epoll_descr *descr)
121	{
122	int i;
123	struct lxc_tty_info *tty_info = data;
124
125	for (i = 0; i < tty_info->nbtty; i++) {
126
127	if (tty_info->pty_info[i].busy != fd)
128	continue;
129
130	lxc_mainloop_del_handler(descr, fd);
131	tty_info->pty_info[i].busy = 0;
132	close(fd);
133	}
134
135	return 0;
136	}
137
138	static int ttyservice_handler(int fd, void *data,
139	struct lxc_epoll_descr *descr)
140	{
141	int conn, ttynum, val = 1, ret = -1;
142	struct lxc_tty_info *tty_info = data;
143
144	conn = accept(fd, NULL, 0);
145	if (conn < 0) {
146	lxc_log_syserror("failed to accept tty client");
147	return -1;
148	}
149
150	if (setsockopt(conn, SOL_SOCKET, SO_PASSCRED, &val, sizeof(val))) {
151	lxc_log_syserror("failed to enable credential on socket");
152	goto out_close;
153	}
154
155	if (lxc_af_unix_rcv_credential(conn, &ttynum, sizeof(ttynum)))
156	goto out_close;
157
158	if (ttynum <= 0 \|\| ttynum > tty_info->nbtty)
159	goto out_close;
160
161	/* fixup index array (eg. tty1 is index 0) */
162	ttynum--;
163
164	if (tty_info->pty_info[ttynum].busy)
165	goto out_close;
166
167	if (lxc_af_unix_send_fd(conn, tty_info->pty_info[ttynum].master,
168	NULL, 0) < 0) {
169	lxc_log_error("failed to send tty to client");
170	goto out_close;
171	}
172
173	if (lxc_mainloop_add_handler(descr, conn,
174	ttyclient_handler, tty_info)) {
175	lxc_log_error("failed to add tty client handler");
176	goto out_close;
177	}
178
179	tty_info->pty_info[ttynum].busy = conn;
180
181	ret = 0;
182
183	out:
184	return ret;
185	out_close:
186	close(conn);
187	goto out;
188	}
189
190	static int mainloop(const char *name, pid_t pid, int sigfd,
191	const struct lxc_tty_info *tty_info)
192	{
193	int nfds, ttyfd = -1, ret = -1;
194	struct lxc_epoll_descr descr;
195
196	if (tty_info->nbtty && setup_tty_service(name, &ttyfd)) {
197	lxc_log_error("failed to create the tty service point");
198	goto out_sigfd;
199	}
200
201	/* sigfd + nb tty + tty service
202	* if tty is enabled */
203	nfds = tty_info->nbtty + 1 + tty_info->nbtty ? 1 : 0;
204
205	if (lxc_mainloop_open(nfds, &descr)) {
206	lxc_log_error("failed to create mainloop");
207	goto out_ttyfd;
208	}
209
210	if (lxc_mainloop_add_handler(&descr, sigfd, sigchld_handler, &pid)) {
211	lxc_log_error("failed to add handler for the signal");
212	goto out_mainloop_open;
213	}
214
215	if (tty_info->nbtty) {
216	if (lxc_mainloop_add_handler(&descr, ttyfd,
217	ttyservice_handler,
218	(void *)tty_info)) {
219	lxc_log_error("failed to add handler for the tty");
220	goto out_mainloop_open;
221	}
222	}
223
224	ret = lxc_mainloop(&descr);
225
226	out:
227	return ret;
228
229	out_mainloop_open:
230	lxc_mainloop_close(&descr);
231	out_ttyfd:
232	close(ttyfd);
233	out_sigfd:
234	close(sigfd);
235	goto out;
236	}
237
05f05512	238	int lxc_start(const char name, char argv[])
0ad19a3f	239	{
b0a33c1e	240	struct lxc_tty_info tty_info = { 0 };
b0a33c1e	241	sigset_t oldmask;
22ebac19	242	char init[MAXPATHLEN];
939229eb	243	char tty[MAXPATHLEN];
22ebac19	244	char *val = NULL;
b0a33c1e	245	int fd, sigfd, lock, sv[2], sync = 0, err = -LXC_ERROR_INTERNAL;
0ad19a3f	246	pid_t pid;
0ad19a3f	247	int clone_flags;
f4d507d5	248
0ad19a3f	249	lock = lxc_get_lock(name);
b0a33c1e	250	if (lock < 0)
b0a33c1e	251	return lock;
0ad19a3f	252
0ad19a3f	253	/* Begin the set the state to STARTING*/
0ad19a3f	254	if (lxc_setstate(name, STARTING)) {
8b8b04f8	255	lxc_log_error("failed to set state '%s'",
8b8b04f8	256	lxc_state2str(STARTING));
0ad19a3f	257	goto out;
	258	}
	259
caf249f4	260	/* If we are not attached to a tty, disable it */
caf249f4	261	if (ttyname_r(0, tty, sizeof(tty)))
939229eb	262	tty[0] = '\0';
939229eb	263
b0a33c1e	264	if (lxc_create_tty(name, &tty_info)) {
	265	lxc_log_error("failed to create the ttys");
	266	goto out;
	267	}
	268
	269	/* the signal fd has to be created before forking otherwise
	270	* if the child process exits before we setup the signal fd,
	271	* the event will be lost and the command will be stuck */
	272	sigfd = setup_sigchld_fd(&oldmask);
	273	if (sigfd < 0) {
	274	lxc_log_error("failed to set sigchild fd handler");
	275	return -1;
	276	}
	277
0ad19a3f	278	/* Synchro socketpair */
	279	if (socketpair(AF_LOCAL, SOCK_STREAM, 0, sv)) {
	280	lxc_log_syserror("failed to create communication socketpair");
f4d507d5	281	goto out;
0ad19a3f	282	}
	283
	284	/* Avoid signals from terminal */
	285	LXC_TTY_ADD_HANDLER(SIGINT);
	286	LXC_TTY_ADD_HANDLER(SIGQUIT);
	287
f4d507d5	288	clone_flags = CLONE_NEWPID\|CLONE_NEWIPC\|CLONE_NEWNS;
0ad19a3f	289	if (conf_has_utsname(name))
	290	clone_flags \|= CLONE_NEWUTS;
	291	if (conf_has_network(name))
	292	clone_flags \|= CLONE_NEWNET;
	293
	294	/* Create a process in a new set of namespaces */
	295	pid = fork_ns(clone_flags);
	296	if (pid < 0) {
	297	lxc_log_syserror("failed to fork into a new namespace");
	298	goto err_fork_ns;
	299	}
	300
	301	if (!pid) {
	302
b0a33c1e	303	if (sigprocmask(SIG_SETMASK, &oldmask, NULL)) {
	304	lxc_log_syserror("failed to set sigprocmask");
	305	return -1;
	306	}
	307
0ad19a3f	308	close(sv[1]);
	309
	310	/* Be sure we don't inherit this after the exec */
	311	fcntl(sv[0], F_SETFD, FD_CLOEXEC);
	312
	313	/* Tell our father he can begin to configure the container */
	314	if (write(sv[0], &sync, sizeof(sync)) < 0) {
	315	lxc_log_syserror("failed to write socket");
57545890	316	goto out_child;
0ad19a3f	317	}
	318
	319	/* Wait for the father to finish the configuration */
	320	if (read(sv[0], &sync, sizeof(sync)) < 0) {
	321	lxc_log_syserror("failed to read socket");
57545890	322	goto out_child;
0ad19a3f	323	}
	324
	325	/* Setup the container, ip, names, utsname, ... */
b0a33c1e	326	err = lxc_setup(name, tty, &tty_info);
e5bda9ee	327	if (err) {
0ad19a3f	328	lxc_log_error("failed to setup the container");
e5bda9ee	329	if (write(sv[0], &err, sizeof(err)) < 0)
0ad19a3f	330	lxc_log_syserror("failed to write the socket");
57545890	331	goto out_child;
0ad19a3f	332	}
0ad19a3f	333
42ff343d	334	if (prctl(PR_CAPBSET_DROP, CAP_SYS_BOOT, 0, 0, 0)) {
	335	lxc_log_syserror("failed to remove CAP_SYS_BOOT capability");
	336	goto out_child;
	337	}
	338
0ad19a3f	339	execvp(argv[0], argv);
	340	lxc_log_syserror("failed to exec %s", argv[0]);
	341
b3223262	342	err = LXC_ERROR_WRONG_COMMAND;
0ad19a3f	343	/* If the exec fails, tell that to our father */
e5bda9ee	344	if (write(sv[0], &err, sizeof(err)) < 0)
0ad19a3f	345	lxc_log_syserror("failed to write the socket");
0ad19a3f	346
57545890	347	out_child:
e5bda9ee	348	exit(err);
0ad19a3f	349	}
	350
	351	close(sv[0]);
	352
	353	/* Wait for the child to be ready */
	354	if (read(sv[1], &sync, sizeof(sync)) < 0) {
	355	lxc_log_syserror("failed to read the socket");
	356	goto err_pipe_read;
	357	}
	358
218d4250	359	if (lxc_link_nsgroup(name, pid))
	360	lxc_log_warning("cgroupfs not found: cgroup disabled");
	361
0ad19a3f	362	/* Create the network configuration */
	363	if (clone_flags & CLONE_NEWNET && conf_create_network(name, pid)) {
	364	lxc_log_error("failed to create the configured network");
	365	goto err_create_network;
	366	}
	367
	368	/* Tell the child to continue its initialization */
	369	if (write(sv[1], &sync, sizeof(sync)) < 0) {
	370	lxc_log_syserror("failed to write the socket");
	371	goto err_pipe_write;
	372	}
	373
	374	/* Wait for the child to exec or returning an error */
	375	err = read(sv[1], &sync, sizeof(sync));
	376	if (err < 0) {
	377	lxc_log_error("failed to read the socket");
	378	goto err_pipe_read2;
	379	}
	380
	381	if (err > 0) {
e5bda9ee	382	err = sync;
0ad19a3f	383	waitpid(pid, NULL, 0);
	384	goto err_child_failed;
	385	}
	386
	387	asprintf(&val, "%d\n", pid);
22ebac19	388
	389	snprintf(init, MAXPATHLEN, LXCPATH "/%s/init", name);
	390
0ad19a3f	391	fd = open(init, O_WRONLY\|O_CREAT\|O_TRUNC, S_IRUSR\|S_IWUSR);
	392	if (fd < 0) {
	393	lxc_log_syserror("failed to open '%s'", init);
	394	goto err_write;
	395	}
	396
	397	if (write(fd, val, strlen(val)) < 0) {
	398	lxc_log_syserror("failed to write the init pid");
	399	goto err_write;
	400	}
	401
	402	close(fd);
	403
0ad19a3f	404	if (lxc_setstate(name, RUNNING)) {
	405	lxc_log_error("failed to set state to %s",
	406	lxc_state2str(RUNNING));
	407	goto err_state_failed;
	408	}
	409
b0a33c1e	410	if (mainloop(name, pid, sigfd, &tty_info)) {
	411	lxc_log_error("mainloop exited with an error");
	412	goto err_mailoop_failed;
0ad19a3f	413	}
	414
	415	if (lxc_setstate(name, STOPPING))
	416	lxc_log_error("failed to set state %s", lxc_state2str(STOPPING));
	417
	418	if (clone_flags & CLONE_NEWNET && conf_destroy_network(name))
	419	lxc_log_error("failed to destroy the network");
	420
	421	err = 0;
	422	out:
	423	if (lxc_setstate(name, STOPPED))
	424	lxc_log_error("failed to set state %s", lxc_state2str(STOPPED));
	425
b0a33c1e	426	lxc_delete_tty(&tty_info);
0ad19a3f	427	lxc_unlink_nsgroup(name);
0ad19a3f	428	unlink(init);
0ad19a3f	429	free(val);
0ad19a3f	430	lxc_put_lock(lock);
536b97f0	431	LXC_TTY_DEL_HANDLER(SIGQUIT);
536b97f0	432	LXC_TTY_DEL_HANDLER(SIGINT);
0ad19a3f	433
	434	return err;
	435
	436	err_write:
	437	close(fd);
	438
	439	err_state_failed:
	440	err_child_failed:
	441	err_pipe_read2:
	442	err_pipe_write:
	443	if (clone_flags & CLONE_NEWNET)
	444	conf_destroy_network(name);
	445	err_create_network:
	446	err_pipe_read:
b0a33c1e	447	err_mailoop_failed:
0ad19a3f	448	if (lxc_setstate(name, ABORTING))
	449	lxc_log_error("failed to set state %s", lxc_state2str(STOPPED));
	450
	451	kill(pid, SIGKILL);
	452	err_fork_ns:
0ad19a3f	453	close(sv[0]);
0ad19a3f	454	close(sv[1]);
0ad19a3f	455	goto out;
0ad19a3f	456	}