X-Git-Url: https://git.lttng.org/?p=lttng-tools.git;a=blobdiff_plain;f=src%2Fbin%2Flttng-sessiond%2Fsession.c;h=e7904472fb9f5f19113bef0e247160aaff999d38;hp=bcdd78d50e68b921f47ceb4038311c625aee875d;hb=1c1c3634276842a00492e24c3adcf847ae21edc3;hpb=fc4705fe99b46c430112590c66abd74e4191c388 diff --git a/src/bin/lttng-sessiond/session.c b/src/bin/lttng-sessiond/session.c index bcdd78d50..e7904472f 100644 --- a/src/bin/lttng-sessiond/session.c +++ b/src/bin/lttng-sessiond/session.c @@ -17,6 +17,7 @@ #define _GNU_SOURCE #include +#include #include #include #include @@ -45,19 +46,57 @@ 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 = "/"; + +/* + * 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 unsigned 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++; } /* @@ -67,11 +106,9 @@ static unsigned int add_session_list(struct ltt_session *ls) */ 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--; - } } /* @@ -103,6 +140,8 @@ void session_unlock_list(void) */ void session_lock(struct ltt_session *session) { + assert(session); + pthread_mutex_lock(&session->lock); } @@ -111,6 +150,8 @@ void session_lock(struct ltt_session *session) */ void session_unlock(struct ltt_session *session) { + assert(session); + pthread_mutex_unlock(&session->lock); } @@ -123,6 +164,8 @@ struct ltt_session *session_find_by_name(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) { @@ -141,69 +184,68 @@ found: * 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); del_session_list(session); pthread_mutex_destroy(&session->lock); + + consumer_destroy_output(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; @@ -214,14 +256,10 @@ int session_create(char *name, char *path, uid_t uid, gid_t gid) 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; } /* Add new session to the session list */ @@ -229,19 +267,35 @@ int session_create(char *name, char *path, uid_t uid, gid_t gid) new_session->id = add_session_list(new_session); session_unlock_list(); - DBG("Tracing session %s created in %s with ID %u 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; + } +}