[lttng-tools.git] / src / bin / lttng-relayd / health-relayd.c

/*
 * Copyright (C) 2013 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License, version 2 only,
 * as published by the Free Software Foundation.
 *
 * This program 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 this program; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 */

#define _GNU_SOURCE
#define _LGPL_SOURCE
#include <fcntl.h>
#include <getopt.h>
#include <grp.h>
#include <limits.h>
#include <pthread.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/ipc.h>
#include <sys/resource.h>
#include <sys/shm.h>
#include <sys/socket.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <urcu/list.h>
#include <poll.h>
#include <unistd.h>
#include <sys/mman.h>
#include <assert.h>
#include <config.h>
#include <urcu/compiler.h>
#include <ulimit.h>
#include <inttypes.h>

#include <common/defaults.h>
#include <common/common.h>
#include <common/consumer.h>
#include <common/consumer-timer.h>
#include <common/compat/poll.h>
#include <common/sessiond-comm/sessiond-comm.h>
#include <common/utils.h>
#include <common/compat/getenv.h>

#include "lttng-relayd.h"
#include "health-relayd.h"

/* Global health check unix path */
static
char health_unix_sock_path[PATH_MAX];

int health_quit_pipe[2];

/*
 * Check if the thread quit pipe was triggered.
 *
 * Return 1 if it was triggered else 0;
 */
static
int check_health_quit_pipe(int fd, uint32_t events)
{
	if (fd == health_quit_pipe[0] && (events & LPOLLIN)) {
		return 1;
	}

	return 0;
}

/*
 * Send data on a unix socket using the liblttsessiondcomm API.
 *
 * Return lttcomm error code.
 */
static int send_unix_sock(int sock, void *buf, size_t len)
{
	/* Check valid length */
	if (len == 0) {
		return -1;
	}

	return lttcomm_send_unix_sock(sock, buf, len);
}

static int create_lttng_rundir_with_perm(const char *rundir)
{
	int ret;

	DBG3("Creating LTTng run directory: %s", rundir);

	ret = mkdir(rundir, S_IRWXU);
	if (ret < 0) {
		if (errno != EEXIST) {
			ERR("Unable to create %s", rundir);
			goto error;
		} else {
			ret = 0;
		}
	} else if (ret == 0) {
		int is_root = !getuid();

		if (is_root) {
			ret = chown(rundir, 0,
					utils_get_group_id(tracing_group_name));
			if (ret < 0) {
				ERR("Unable to set group on %s", rundir);
				PERROR("chown");
				ret = -1;
				goto error;
			}

			ret = chmod(rundir,
					S_IRUSR | S_IWUSR | S_IXUSR | S_IRGRP | S_IXGRP | S_IROTH | S_IXOTH);
			if (ret < 0) {
				ERR("Unable to set permissions on %s", health_unix_sock_path);
				PERROR("chmod");
				ret = -1;
				goto error;
			}
		}
	}

error:
	return ret;
}

static
int parse_health_env(void)
{
	const char *health_path;

	health_path = lttng_secure_getenv(LTTNG_RELAYD_HEALTH_ENV);
	if (health_path) {
		strncpy(health_unix_sock_path, health_path,
			PATH_MAX);
		health_unix_sock_path[PATH_MAX - 1] = '\0';
	}

	return 0;
}

static
int setup_health_path(void)
{
	int is_root, ret = 0;
	char *home_path = NULL, *rundir = NULL, *relayd_path;

	ret = parse_health_env();
	if (ret) {
		return ret;
	}

	is_root = !getuid();

	if (is_root) {
		rundir = strdup(DEFAULT_LTTNG_RUNDIR);
		if (!rundir) {
			ret = -ENOMEM;
			goto end;
		}
	} else {
		/*
		 * Create rundir from home path. This will create something like
		 * $HOME/.lttng
		 */
		home_path = utils_get_home_dir();

		if (home_path == NULL) {
			/* TODO: Add --socket PATH option */
			ERR("Can't get HOME directory for sockets creation.");
			ret = -EPERM;
			goto end;
		}

		ret = asprintf(&rundir, DEFAULT_LTTNG_HOME_RUNDIR, home_path);
		if (ret < 0) {
			ret = -ENOMEM;
			goto end;
		}
	}

	ret = asprintf(&relayd_path, DEFAULT_RELAYD_PATH, rundir);
	if (ret < 0) {
		ret = -ENOMEM;
		goto end;
	}

	ret = create_lttng_rundir_with_perm(rundir);
	if (ret < 0) {
		goto end;
	}

	ret = create_lttng_rundir_with_perm(relayd_path);
	if (ret < 0) {
		goto end;
	}

	if (is_root) {
		if (strlen(health_unix_sock_path) != 0) {
			goto end;
		}
		snprintf(health_unix_sock_path, sizeof(health_unix_sock_path),
			DEFAULT_GLOBAL_RELAY_HEALTH_UNIX_SOCK,
			getpid());
	} else {
		/* Set health check Unix path */
		if (strlen(health_unix_sock_path) != 0) {
			goto end;
		}

		snprintf(health_unix_sock_path, sizeof(health_unix_sock_path),
			DEFAULT_HOME_RELAY_HEALTH_UNIX_SOCK,
			home_path, getpid());
	}

end:
	free(rundir);
	return ret;
}

/*
 * Thread managing health check socket.
 */
void *thread_manage_health(void *data)
{
	int sock = -1, new_sock = -1, ret, i, pollfd, err = -1;
	uint32_t revents, nb_fd;
	struct lttng_poll_event events;
	struct health_comm_msg msg;
	struct health_comm_reply reply;
	int is_root;

	DBG("[thread] Manage health check started");

	setup_health_path();

	rcu_register_thread();

	/* We might hit an error path before this is created. */
	lttng_poll_init(&events);

	/* Create unix socket */
	sock = lttcomm_create_unix_sock(health_unix_sock_path);
	if (sock < 0) {
		ERR("Unable to create health check Unix socket");
		ret = -1;
		goto error;
	}

	is_root = !getuid();
	if (is_root) {
		/* lttng health client socket path permissions */
		ret = chown(health_unix_sock_path, 0,
				utils_get_group_id(tracing_group_name));
		if (ret < 0) {
			ERR("Unable to set group on %s", health_unix_sock_path);
			PERROR("chown");
			ret = -1;
			goto error;
		}

		ret = chmod(health_unix_sock_path,
				S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP);
		if (ret < 0) {
			ERR("Unable to set permissions on %s", health_unix_sock_path);
			PERROR("chmod");
			ret = -1;
			goto error;
		}
	}

	/*
	 * Set the CLOEXEC flag. Return code is useless because either way, the
	 * show must go on.
	 */
	(void) utils_set_fd_cloexec(sock);

	ret = lttcomm_listen_unix_sock(sock);
	if (ret < 0) {
		goto error;
	}

	/* Size is set to 1 for the consumer_channel pipe */
	ret = lttng_poll_create(&events, 2, LTTNG_CLOEXEC);
	if (ret < 0) {
		ERR("Poll set creation failed");
		goto error;
	}

	ret = lttng_poll_add(&events, health_quit_pipe[0], LPOLLIN);
	if (ret < 0) {
		goto error;
	}

	/* Add the application registration socket */
	ret = lttng_poll_add(&events, sock, LPOLLIN | LPOLLPRI);
	if (ret < 0) {
		goto error;
	}

	lttng_relay_notify_ready();

	while (1) {
		DBG("Health check ready");

		/* Inifinite blocking call, waiting for transmission */
restart:
		ret = lttng_poll_wait(&events, -1);
		if (ret < 0) {
			/*
			 * Restart interrupted system call.
			 */
			if (errno == EINTR) {
				goto restart;
			}
			goto error;
		}

		nb_fd = ret;

		for (i = 0; i < nb_fd; i++) {
			/* Fetch once the poll data */
			revents = LTTNG_POLL_GETEV(&events, i);
			pollfd = LTTNG_POLL_GETFD(&events, i);

			if (!revents) {
				/* No activity for this FD (poll implementation). */
				continue;
			}

			/* Thread quit pipe has been closed. Killing thread. */
			ret = check_health_quit_pipe(pollfd, revents);
			if (ret) {
				err = 0;
				goto exit;
			}

			/* Event on the registration socket */
			if (pollfd == sock) {
				if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
					ERR("Health socket poll error");
					goto error;
				}
			}
		}

		new_sock = lttcomm_accept_unix_sock(sock);
		if (new_sock < 0) {
			goto error;
		}

		/*
		 * Set the CLOEXEC flag. Return code is useless because either way, the
		 * show must go on.
		 */
		(void) utils_set_fd_cloexec(new_sock);

		DBG("Receiving data from client for health...");
		ret = lttcomm_recv_unix_sock(new_sock, (void *)&msg, sizeof(msg));
		if (ret <= 0) {
			DBG("Nothing recv() from client... continuing");
			ret = close(new_sock);
			if (ret) {
				PERROR("close");
			}
			new_sock = -1;
			continue;
		}

		rcu_thread_online();

		assert(msg.cmd == HEALTH_CMD_CHECK);

		memset(&reply, 0, sizeof(reply));
		for (i = 0; i < NR_HEALTH_RELAYD_TYPES; i++) {
			/*
			 * health_check_state return 0 if thread is in
			 * error.
			 */
			if (!health_check_state(health_relayd, i)) {
				reply.ret_code |= 1ULL << i;
			}
		}

		DBG2("Health check return value %" PRIx64, reply.ret_code);

		ret = send_unix_sock(new_sock, (void *) &reply, sizeof(reply));
		if (ret < 0) {
			ERR("Failed to send health data back to client");
		}

		/* End of transmission */
		ret = close(new_sock);
		if (ret) {
			PERROR("close");
		}
		new_sock = -1;
	}

exit:
error:
	if (err) {
		ERR("Health error occurred in %s", __func__);
	}
	DBG("Health check thread dying");
	unlink(health_unix_sock_path);
	if (sock >= 0) {
		ret = close(sock);
		if (ret) {
			PERROR("close");
		}
	}

	/*
	 * We do NOT rmdir rundir nor the relayd path because there are
	 * other processes using them.
	 */

	lttng_poll_clean(&events);

	rcu_unregister_thread();
	return NULL;
}
Commit	Line	Data
65931c8b MD	1	/*
	2	* Copyright (C) 2013 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
	3	*
	4	* This program is free software; you can redistribute it and/or modify
	5	* it under the terms of the GNU General Public License, version 2 only,
	6	* as published by the Free Software Foundation.
	7	*
	8	* This program is distributed in the hope that it will be useful,
	9	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	10	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	11	* GNU General Public License for more details.
	12	*
	13	* You should have received a copy of the GNU General Public License along
	14	* with this program; if not, write to the Free Software Foundation, Inc.,
	15	* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
	16	*/
	17
	18	#define _GNU_SOURCE
6c1c0768	19	#define _LGPL_SOURCE
65931c8b MD	20	#include <fcntl.h>
	21	#include <getopt.h>
	22	#include <grp.h>
	23	#include <limits.h>
	24	#include <pthread.h>
	25	#include <signal.h>
	26	#include <stdio.h>
	27	#include <stdlib.h>
	28	#include <string.h>
	29	#include <sys/ipc.h>
	30	#include <sys/resource.h>
	31	#include <sys/shm.h>
	32	#include <sys/socket.h>
	33	#include <sys/stat.h>
	34	#include <sys/types.h>
	35	#include <urcu/list.h>
	36	#include <poll.h>
	37	#include <unistd.h>
	38	#include <sys/mman.h>
	39	#include <assert.h>
	40	#include <config.h>
	41	#include <urcu/compiler.h>
	42	#include <ulimit.h>
	43	#include <inttypes.h>
	44
	45	#include <common/defaults.h>
	46	#include <common/common.h>
	47	#include <common/consumer.h>
	48	#include <common/consumer-timer.h>
	49	#include <common/compat/poll.h>
	50	#include <common/sessiond-comm/sessiond-comm.h>
	51	#include <common/utils.h>
e8fa9fb0	52	#include <common/compat/getenv.h>
65931c8b MD	53
	54	#include "lttng-relayd.h"
	55	#include "health-relayd.h"
	56
	57	/* Global health check unix path */
094fe907 MD	58	static
094fe907 MD	59	char health_unix_sock_path[PATH_MAX];
65931c8b MD	60
	61	int health_quit_pipe[2];
	62
	63	/*
	64	* Check if the thread quit pipe was triggered.
	65	*
	66	* Return 1 if it was triggered else 0;
	67	*/
	68	static
	69	int check_health_quit_pipe(int fd, uint32_t events)
	70	{
	71	if (fd == health_quit_pipe[0] && (events & LPOLLIN)) {
	72	return 1;
	73	}
	74
	75	return 0;
	76	}
	77
	78	/*
	79	* Send data on a unix socket using the liblttsessiondcomm API.
	80	*
	81	* Return lttcomm error code.
	82	*/
	83	static int send_unix_sock(int sock, void *buf, size_t len)
	84	{
	85	/* Check valid length */
	86	if (len == 0) {
	87	return -1;
	88	}
	89
	90	return lttcomm_send_unix_sock(sock, buf, len);
	91	}
	92
	93	static int create_lttng_rundir_with_perm(const char *rundir)
	94	{
	95	int ret;
	96
	97	DBG3("Creating LTTng run directory: %s", rundir);
	98
	99	ret = mkdir(rundir, S_IRWXU);
	100	if (ret < 0) {
	101	if (errno != EEXIST) {
	102	ERR("Unable to create %s", rundir);
	103	goto error;
	104	} else {
	105	ret = 0;
	106	}
	107	} else if (ret == 0) {
	108	int is_root = !getuid();
	109
	110	if (is_root) {
	111	ret = chown(rundir, 0,
	112	utils_get_group_id(tracing_group_name));
	113	if (ret < 0) {
	114	ERR("Unable to set group on %s", rundir);
	115	PERROR("chown");
	116	ret = -1;
	117	goto error;
	118	}
	119
	120	ret = chmod(rundir,
	121	S_IRUSR \| S_IWUSR \| S_IXUSR \| S_IRGRP \| S_IXGRP \| S_IROTH \| S_IXOTH);
	122	if (ret < 0) {
	123	ERR("Unable to set permissions on %s", health_unix_sock_path);
124	PERROR("chmod");
125	ret = -1;
126	goto error;
127	}
128	}
129	}
130
131	error:
132	return ret;
133	}
134
094fe907 MD	135	static
	136	int parse_health_env(void)
	137	{
	138	const char *health_path;
	139
e8fa9fb0	140	health_path = lttng_secure_getenv(LTTNG_RELAYD_HEALTH_ENV);
094fe907 MD	141	if (health_path) {
	142	strncpy(health_unix_sock_path, health_path,
	143	PATH_MAX);
	144	health_unix_sock_path[PATH_MAX - 1] = '\0';
	145	}
	146
	147	return 0;
	148	}
	149
65931c8b MD	150	static
	151	int setup_health_path(void)
	152	{
	153	int is_root, ret = 0;
c3844e39	154	char home_path = NULL, rundir = NULL, *relayd_path;
65931c8b	155
094fe907 MD	156	ret = parse_health_env();
	157	if (ret) {
	158	return ret;
	159	}
	160
65931c8b MD	161	is_root = !getuid();
	162
	163	if (is_root) {
c3844e39	164	rundir = strdup(DEFAULT_LTTNG_RUNDIR);
b6ab01aa MD	165	if (!rundir) {
	166	ret = -ENOMEM;
	167	goto end;
	168	}
65931c8b MD	169	} else {
	170	/*
	171	* Create rundir from home path. This will create something like
	172	* $HOME/.lttng
	173	*/
	174	home_path = utils_get_home_dir();
	175
	176	if (home_path == NULL) {
	177	/* TODO: Add --socket PATH option */
	178	ERR("Can't get HOME directory for sockets creation.");
	179	ret = -EPERM;
	180	goto end;
	181	}
	182
c3844e39	183	ret = asprintf(&rundir, DEFAULT_LTTNG_HOME_RUNDIR, home_path);
65931c8b MD	184	if (ret < 0) {
	185	ret = -ENOMEM;
	186	goto end;
	187	}
	188	}
	189
c3844e39	190	ret = asprintf(&relayd_path, DEFAULT_RELAYD_PATH, rundir);
65931c8b MD	191	if (ret < 0) {
	192	ret = -ENOMEM;
	193	goto end;
	194	}
	195
c3844e39	196	ret = create_lttng_rundir_with_perm(rundir);
65931c8b MD	197	if (ret < 0) {
	198	goto end;
	199	}
	200
	201	ret = create_lttng_rundir_with_perm(relayd_path);
	202	if (ret < 0) {
	203	goto end;
	204	}
	205
	206	if (is_root) {
	207	if (strlen(health_unix_sock_path) != 0) {
	208	goto end;
	209	}
	210	snprintf(health_unix_sock_path, sizeof(health_unix_sock_path),
	211	DEFAULT_GLOBAL_RELAY_HEALTH_UNIX_SOCK,
	212	getpid());
	213	} else {
	214	/* Set health check Unix path */
	215	if (strlen(health_unix_sock_path) != 0) {
	216	goto end;
	217	}
	218
	219	snprintf(health_unix_sock_path, sizeof(health_unix_sock_path),
	220	DEFAULT_HOME_RELAY_HEALTH_UNIX_SOCK,
	221	home_path, getpid());
	222	}
	223
	224	end:
c3844e39	225	free(rundir);
65931c8b MD	226	return ret;
	227	}
	228
	229	/*
	230	* Thread managing health check socket.
	231	*/
	232	void thread_manage_health(void data)
	233	{
	234	int sock = -1, new_sock = -1, ret, i, pollfd, err = -1;
	235	uint32_t revents, nb_fd;
	236	struct lttng_poll_event events;
	237	struct health_comm_msg msg;
	238	struct health_comm_reply reply;
	239	int is_root;
	240
	241	DBG("[thread] Manage health check started");
	242
	243	setup_health_path();
	244
	245	rcu_register_thread();
	246
	247	/* We might hit an error path before this is created. */
	248	lttng_poll_init(&events);
	249
	250	/* Create unix socket */
	251	sock = lttcomm_create_unix_sock(health_unix_sock_path);
	252	if (sock < 0) {
	253	ERR("Unable to create health check Unix socket");
	254	ret = -1;
	255	goto error;
	256	}
	257
	258	is_root = !getuid();
	259	if (is_root) {
	260	/* lttng health client socket path permissions */
	261	ret = chown(health_unix_sock_path, 0,
	262	utils_get_group_id(tracing_group_name));
	263	if (ret < 0) {
	264	ERR("Unable to set group on %s", health_unix_sock_path);
	265	PERROR("chown");
	266	ret = -1;
	267	goto error;
	268	}
	269
	270	ret = chmod(health_unix_sock_path,
	271	S_IRUSR \| S_IWUSR \| S_IRGRP \| S_IWGRP);
	272	if (ret < 0) {
	273	ERR("Unable to set permissions on %s", health_unix_sock_path);
	274	PERROR("chmod");
	275	ret = -1;
	276	goto error;
	277	}
	278	}
	279
	280	/*
	281	* Set the CLOEXEC flag. Return code is useless because either way, the
	282	* show must go on.
	283	*/
	284	(void) utils_set_fd_cloexec(sock);
	285
	286	ret = lttcomm_listen_unix_sock(sock);
	287	if (ret < 0) {
	288	goto error;
	289	}
290
291	/* Size is set to 1 for the consumer_channel pipe */
292	ret = lttng_poll_create(&events, 2, LTTNG_CLOEXEC);
293	if (ret < 0) {
294	ERR("Poll set creation failed");
295	goto error;
296	}
297
298	ret = lttng_poll_add(&events, health_quit_pipe[0], LPOLLIN);
299	if (ret < 0) {
300	goto error;
301	}
302
303	/* Add the application registration socket */
304	ret = lttng_poll_add(&events, sock, LPOLLIN \| LPOLLPRI);
305	if (ret < 0) {
306	goto error;
307	}
308
3fd27398 MD	309	lttng_relay_notify_ready();
3fd27398 MD	310
65931c8b MD	311	while (1) {
	312	DBG("Health check ready");
	313
	314	/* Inifinite blocking call, waiting for transmission */
	315	restart:
	316	ret = lttng_poll_wait(&events, -1);
	317	if (ret < 0) {
	318	/*
	319	* Restart interrupted system call.
	320	*/
	321	if (errno == EINTR) {
	322	goto restart;
	323	}
	324	goto error;
	325	}
	326
	327	nb_fd = ret;
	328
	329	for (i = 0; i < nb_fd; i++) {
	330	/* Fetch once the poll data */
	331	revents = LTTNG_POLL_GETEV(&events, i);
	332	pollfd = LTTNG_POLL_GETFD(&events, i);
	333
fd20dac9 MD	334	if (!revents) {
	335	/* No activity for this FD (poll implementation). */
	336	continue;
	337	}
	338
65931c8b MD	339	/* Thread quit pipe has been closed. Killing thread. */
	340	ret = check_health_quit_pipe(pollfd, revents);
	341	if (ret) {
	342	err = 0;
	343	goto exit;
	344	}
	345
	346	/* Event on the registration socket */
	347	if (pollfd == sock) {
	348	if (revents & (LPOLLERR \| LPOLLHUP \| LPOLLRDHUP)) {
	349	ERR("Health socket poll error");
	350	goto error;
	351	}
	352	}
	353	}
	354
	355	new_sock = lttcomm_accept_unix_sock(sock);
	356	if (new_sock < 0) {
	357	goto error;
	358	}
	359
	360	/*
	361	* Set the CLOEXEC flag. Return code is useless because either way, the
	362	* show must go on.
	363	*/
	364	(void) utils_set_fd_cloexec(new_sock);
	365
	366	DBG("Receiving data from client for health...");
	367	ret = lttcomm_recv_unix_sock(new_sock, (void *)&msg, sizeof(msg));
	368	if (ret <= 0) {
	369	DBG("Nothing recv() from client... continuing");
	370	ret = close(new_sock);
	371	if (ret) {
	372	PERROR("close");
	373	}
	374	new_sock = -1;
	375	continue;
	376	}
	377
	378	rcu_thread_online();
	379
	380	assert(msg.cmd == HEALTH_CMD_CHECK);
	381
53efb85a	382	memset(&reply, 0, sizeof(reply));
65931c8b MD	383	for (i = 0; i < NR_HEALTH_RELAYD_TYPES; i++) {
	384	/*
	385	* health_check_state return 0 if thread is in
	386	* error.
	387	*/
	388	if (!health_check_state(health_relayd, i)) {
	389	reply.ret_code \|= 1ULL << i;
	390	}
	391	}
	392
	393	DBG2("Health check return value %" PRIx64, reply.ret_code);
	394
	395	ret = send_unix_sock(new_sock, (void *) &reply, sizeof(reply));
	396	if (ret < 0) {
	397	ERR("Failed to send health data back to client");
	398	}
	399
	400	/* End of transmission */
	401	ret = close(new_sock);
	402	if (ret) {
	403	PERROR("close");
	404	}
	405	new_sock = -1;
	406	}
	407
	408	exit:
	409	error:
	410	if (err) {
	411	ERR("Health error occurred in %s", __func__);
	412	}
	413	DBG("Health check thread dying");
	414	unlink(health_unix_sock_path);
	415	if (sock >= 0) {
	416	ret = close(sock);
	417	if (ret) {
	418	PERROR("close");
	419	}
	420	}
	421
dcbcae3e MD	422	/*
	423	* We do NOT rmdir rundir nor the relayd path because there are
	424	* other processes using them.
	425	*/
	426
65931c8b MD	427	lttng_poll_clean(&events);
	428
	429	rcu_unregister_thread();
	430	return NULL;
	431	}