/*
* Copyright (C) 2011 - David Goulet <david.goulet@polymtl.ca>
*
- * This program 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; only version 2
- * of the License.
+ * 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
+ * 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ * 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 <limits.h>
+#include <inttypes.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/stat.h>
-#include <sys/types.h>
#include <urcu.h>
+#include <dirent.h>
+#include <sys/types.h>
#include <common/common.h>
#include <common/sessiond-comm/sessiond-comm.h>
#include "session.h"
+#include "utils.h"
+#include "trace-ust.h"
/*
* NOTES:
static struct ltt_session_list ltt_session_list = {
.head = CDS_LIST_HEAD_INIT(ltt_session_list.head),
.lock = PTHREAD_MUTEX_INITIALIZER,
- .count = 0,
+ .next_uuid = 0,
};
+/* These characters are forbidden in a session name. Used by validate_name. */
+static const char *forbidden_name_chars = "/";
+
+/* Global hash table to keep the sessions, indexed by id. */
+static struct lttng_ht *ltt_sessions_ht_by_id = NULL;
+
+/*
+ * Validate the session name for forbidden characters.
+ *
+ * Return 0 on success else -1 meaning a forbidden char. has been found.
+ */
+static int validate_name(const char *name)
+{
+ int ret;
+ char *tok, *tmp_name;
+
+ assert(name);
+
+ tmp_name = strdup(name);
+ if (!tmp_name) {
+ /* ENOMEM here. */
+ ret = -1;
+ goto error;
+ }
+
+ tok = strpbrk(tmp_name, forbidden_name_chars);
+ if (tok) {
+ DBG("Session name %s contains a forbidden character", name);
+ /* Forbidden character has been found. */
+ ret = -1;
+ goto error;
+ }
+ ret = 0;
+
+error:
+ free(tmp_name);
+ return ret;
+}
+
/*
* Add a ltt_session structure to the global list.
*
* The caller MUST acquire the session list lock before.
* Returns the unique identifier for the session.
*/
-static int add_session_list(struct ltt_session *ls)
+static uint64_t add_session_list(struct ltt_session *ls)
{
+ assert(ls);
+
cds_list_add(&ls->list, <t_session_list.head);
- return ++ltt_session_list.count;
+ return ltt_session_list.next_uuid++;
}
/*
*/
static void del_session_list(struct ltt_session *ls)
{
+ assert(ls);
+
cds_list_del(&ls->list);
- /* Sanity check */
- if (ltt_session_list.count > 0) {
- ltt_session_list.count--;
- }
}
/*
pthread_mutex_lock(<t_session_list.lock);
}
+/*
+ * Try to acquire session list lock
+ */
+int session_trylock_list(void)
+{
+ return pthread_mutex_trylock(<t_session_list.lock);
+}
+
/*
* Release session list lock
*/
pthread_mutex_unlock(<t_session_list.lock);
}
+/*
+ * Get the session's consumer destination type.
+ *
+ * The caller must hold the session lock.
+ */
+enum consumer_dst_type session_get_consumer_destination_type(
+ const struct ltt_session *session)
+{
+ /*
+ * The output information is duplicated in both of those session types.
+ * Hence, it doesn't matter from which it is retrieved. However, it is
+ * possible for only one of them to be set.
+ */
+ return session->kernel_session ?
+ session->kernel_session->consumer->type :
+ session->ust_session->consumer->type;
+}
+
+/*
+ * Get the session's consumer network hostname.
+ * The caller must ensure that the destination is of type "net".
+ *
+ * The caller must hold the session lock.
+ */
+const char *session_get_net_consumer_hostname(const struct ltt_session *session)
+{
+ const char *hostname = NULL;
+ const struct consumer_output *output;
+
+ output = session->kernel_session ?
+ session->kernel_session->consumer :
+ session->ust_session->consumer;
+
+ /*
+ * hostname is assumed to be the same for both control and data
+ * connections.
+ */
+ switch (output->dst.net.control.dtype) {
+ case LTTNG_DST_IPV4:
+ hostname = output->dst.net.control.dst.ipv4;
+ break;
+ case LTTNG_DST_IPV6:
+ hostname = output->dst.net.control.dst.ipv6;
+ break;
+ default:
+ abort();
+ }
+ return hostname;
+}
+
+/*
+ * Get the session's consumer network control and data ports.
+ * The caller must ensure that the destination is of type "net".
+ *
+ * The caller must hold the session lock.
+ */
+void session_get_net_consumer_ports(const struct ltt_session *session,
+ uint16_t *control_port, uint16_t *data_port)
+{
+ const struct consumer_output *output;
+
+ output = session->kernel_session ?
+ session->kernel_session->consumer :
+ session->ust_session->consumer;
+ *control_port = output->dst.net.control.port;
+ *data_port = output->dst.net.data.port;
+}
+
+/*
+ * Allocate the ltt_sessions_ht_by_id HT.
+ *
+ * The session list lock must be held.
+ */
+int ltt_sessions_ht_alloc(void)
+{
+ int ret = 0;
+
+ DBG("Allocating ltt_sessions_ht_by_id");
+ ltt_sessions_ht_by_id = lttng_ht_new(0, LTTNG_HT_TYPE_U64);
+ if (!ltt_sessions_ht_by_id) {
+ ret = -1;
+ ERR("Failed to allocate ltt_sessions_ht_by_id");
+ goto end;
+ }
+end:
+ return ret;
+}
+
+/*
+ * Destroy the ltt_sessions_ht_by_id HT.
+ *
+ * The session list lock must be held.
+ */
+static void ltt_sessions_ht_destroy(void)
+{
+ if (!ltt_sessions_ht_by_id) {
+ return;
+ }
+ ht_cleanup_push(ltt_sessions_ht_by_id);
+ ltt_sessions_ht_by_id = NULL;
+}
+
+/*
+ * Add a ltt_session to the ltt_sessions_ht_by_id.
+ * If unallocated, the ltt_sessions_ht_by_id HT is allocated.
+ * The session list lock must be held.
+ */
+static void add_session_ht(struct ltt_session *ls)
+{
+ int ret;
+
+ assert(ls);
+
+ if (!ltt_sessions_ht_by_id) {
+ ret = ltt_sessions_ht_alloc();
+ if (ret) {
+ ERR("Error allocating the sessions HT");
+ goto end;
+ }
+ }
+ lttng_ht_node_init_u64(&ls->node, ls->id);
+ lttng_ht_add_unique_u64(ltt_sessions_ht_by_id, &ls->node);
+
+end:
+ return;
+}
+
+/*
+ * Test if ltt_sessions_ht_by_id is empty.
+ * Return 1 if empty, 0 if not empty.
+ * The session list lock must be held.
+ */
+static int ltt_sessions_ht_empty(void)
+{
+ int ret;
+
+ if (!ltt_sessions_ht_by_id) {
+ ret = 1;
+ goto end;
+ }
+
+ ret = lttng_ht_get_count(ltt_sessions_ht_by_id) ? 0 : 1;
+end:
+ return ret;
+}
+
+/*
+ * Remove a ltt_session from the ltt_sessions_ht_by_id.
+ * If empty, the ltt_sessions_ht_by_id HT is freed.
+ * The session list lock must be held.
+ */
+static void del_session_ht(struct ltt_session *ls)
+{
+ struct lttng_ht_iter iter;
+ int ret;
+
+ assert(ls);
+ assert(ltt_sessions_ht_by_id);
+
+ iter.iter.node = &ls->node.node;
+ ret = lttng_ht_del(ltt_sessions_ht_by_id, &iter);
+ assert(!ret);
+
+ if (ltt_sessions_ht_empty()) {
+ DBG("Empty ltt_sessions_ht_by_id, destroying it");
+ ltt_sessions_ht_destroy();
+ }
+}
+
/*
* Acquire session lock
*/
void session_lock(struct ltt_session *session)
{
+ assert(session);
+
pthread_mutex_lock(&session->lock);
}
*/
void session_unlock(struct ltt_session *session)
{
+ assert(session);
+
pthread_mutex_unlock(&session->lock);
}
/*
* Return a ltt_session structure ptr that matches name. If no session found,
- * NULL is returned. This must be called with the session lock held using
+ * NULL is returned. This must be called with the session list lock held using
* session_lock_list and session_unlock_list.
*/
-struct ltt_session *session_find_by_name(char *name)
+struct ltt_session *session_find_by_name(const char *name)
{
struct ltt_session *iter;
+ assert(name);
+
DBG2("Trying to find session by name %s", name);
cds_list_for_each_entry(iter, <t_session_list.head, list) {
return iter;
}
+/*
+ * Return an ltt_session that matches the id. If no session is found,
+ * NULL is returned. This must be called with rcu_read_lock and
+ * session list lock held (to guarantee the lifetime of the session).
+ */
+struct ltt_session *session_find_by_id(uint64_t id)
+{
+ struct lttng_ht_node_u64 *node;
+ struct lttng_ht_iter iter;
+ struct ltt_session *ls;
+
+ if (!ltt_sessions_ht_by_id) {
+ goto end;
+ }
+
+ lttng_ht_lookup(ltt_sessions_ht_by_id, &id, &iter);
+ node = lttng_ht_iter_get_node_u64(&iter);
+ if (node == NULL) {
+ goto end;
+ }
+ ls = caa_container_of(node, struct ltt_session, node);
+
+ DBG3("Session %" PRIu64 " found by id.", id);
+ return ls;
+
+end:
+ DBG3("Session %" PRIu64 " NOT found by id", id);
+ return NULL;
+}
+
/*
* Delete session from the session list and free the memory.
*
* Return -1 if no session is found. On success, return 1;
+ * Should *NOT* be called with RCU read-side lock held.
*/
int session_destroy(struct ltt_session *session)
{
/* Safety check */
- if (session == NULL) {
- ERR("Session pointer was null on session destroy");
- return LTTCOMM_OK;
- }
+ assert(session);
- DBG("Destroying session %s", session->name);
+ DBG("Destroying session %s (id %" PRIu64 ")", session->name, session->id);
del_session_list(session);
pthread_mutex_destroy(&session->lock);
+ del_session_ht(session);
+
+ consumer_output_put(session->consumer);
+ snapshot_destroy(&session->snapshot);
free(session);
- return LTTCOMM_OK;
+ return LTTNG_OK;
}
/*
* Create a brand new session and add it to the session list.
*/
-int session_create(char *name, char *path, uid_t uid, gid_t gid)
+int session_create(char *name, uid_t uid, gid_t gid)
{
int ret;
struct ltt_session *new_session;
- new_session = session_find_by_name(name);
- if (new_session != NULL) {
- ret = LTTCOMM_EXIST_SESS;
- goto error_exist;
- }
-
/* Allocate session data structure */
new_session = zmalloc(sizeof(struct ltt_session));
if (new_session == NULL) {
PERROR("zmalloc");
- ret = LTTCOMM_FATAL;
+ ret = LTTNG_ERR_FATAL;
goto error_malloc;
}
/* Define session name */
if (name != NULL) {
if (snprintf(new_session->name, NAME_MAX, "%s", name) < 0) {
- ret = LTTCOMM_FATAL;
+ ret = LTTNG_ERR_FATAL;
goto error_asprintf;
}
} else {
ERR("No session name given");
- ret = LTTCOMM_FATAL;
+ ret = LTTNG_ERR_FATAL;
goto error;
}
- /* Define session system path */
- if (path != NULL) {
- if (snprintf(new_session->path, PATH_MAX, "%s", path) < 0) {
- ret = LTTCOMM_FATAL;
- goto error_asprintf;
- }
- } else {
- ERR("No session path given");
- ret = LTTCOMM_FATAL;
+ ret = validate_name(name);
+ if (ret < 0) {
+ ret = LTTNG_ERR_SESSION_INVALID_CHAR;
goto error;
}
+ ret = gethostname(new_session->hostname, sizeof(new_session->hostname));
+ if (ret < 0) {
+ if (errno == ENAMETOOLONG) {
+ new_session->hostname[sizeof(new_session->hostname) - 1] = '\0';
+ } else {
+ ret = LTTNG_ERR_FATAL;
+ goto error;
+ }
+ }
+
/* Init kernel session */
new_session->kernel_session = NULL;
new_session->ust_session = NULL;
new_session->uid = uid;
new_session->gid = gid;
- ret = run_as_mkdir_recursive(new_session->path, S_IRWXU | S_IRWXG,
- new_session->uid, new_session->gid);
+ ret = snapshot_init(&new_session->snapshot);
if (ret < 0) {
- if (ret != -EEXIST) {
- ERR("Trace directory creation error");
- ret = LTTCOMM_CREATE_DIR_FAIL;
- goto error;
- }
+ ret = LTTNG_ERR_NOMEM;
+ goto error;
}
+ new_session->rotate_pending = false;
+ new_session->rotation_state = LTTNG_ROTATION_STATE_NO_ROTATION;
+ new_session->rotate_pending_relay = false;
+ new_session->rotate_relay_pending_timer_enabled = false;
+ new_session->rotate_timer = false;
+
/* Add new session to the session list */
session_lock_list();
new_session->id = add_session_list(new_session);
+ /*
+ * Add the new session to the ltt_sessions_ht_by_id.
+ * No ownership is taken by the hash table; it is merely
+ * a wrapper around the session list used for faster access
+ * by session id.
+ */
+ add_session_ht(new_session);
session_unlock_list();
- DBG("Tracing session %s created in %s with ID %d by UID %d GID %d",
- name, path, new_session->id,
- new_session->uid, new_session->gid);
+ /*
+ * Consumer is let to NULL since the create_session_uri command will set it
+ * up and, if valid, assign it to the session.
+ */
+ DBG("Tracing session %s created with ID %" PRIu64 " by UID %d GID %d",
+ name, new_session->id, new_session->uid, new_session->gid);
- return LTTCOMM_OK;
+ return LTTNG_OK;
error:
error_asprintf:
- if (new_session != NULL) {
- free(new_session);
- }
+ free(new_session);
-error_exist:
error_malloc:
return ret;
}
+
+/*
+ * Check if the UID or GID match the session. Root user has access to all
+ * sessions.
+ */
+int session_access_ok(struct ltt_session *session, uid_t uid, gid_t gid)
+{
+ assert(session);
+
+ if (uid != session->uid && gid != session->gid && uid != 0) {
+ return 0;
+ } else {
+ return 1;
+ }
+}
projects / lttng-tools.git / blobdiff