X-Git-Url: http://git.efficios.com/?p=lttng-tools.git;a=blobdiff_plain;f=src%2Fbin%2Flttng-sessiond%2Fsession.c;h=99b0165070ebc296c9f2bc9dc46a6d5967703741;hp=75fcf4bfded58320ab6723e9ae0e574740107b24;hb=6c1c0768320135c6936c371b09731851b508c023;hpb=07424f161f4afbd07fd165e4ae492726e1de7769 diff --git a/src/bin/lttng-sessiond/session.c b/src/bin/lttng-sessiond/session.c index 75fcf4bfd..99b016507 100644 --- a/src/bin/lttng-sessiond/session.c +++ b/src/bin/lttng-sessiond/session.c @@ -16,7 +16,9 @@ */ #define _GNU_SOURCE +#define _LGPL_SOURCE #include +#include #include #include #include @@ -48,14 +50,52 @@ static struct ltt_session_list ltt_session_list = { .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.next_uuid++; } @@ -67,6 +107,8 @@ 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); } @@ -99,6 +141,8 @@ void session_unlock_list(void) */ void session_lock(struct ltt_session *session) { + assert(session); + pthread_mutex_lock(&session->lock); } @@ -107,6 +151,8 @@ void session_lock(struct ltt_session *session) */ void session_unlock(struct ltt_session *session) { + assert(session); + pthread_mutex_unlock(&session->lock); } @@ -115,10 +161,12 @@ void session_unlock(struct ltt_session *session) * NULL is returned. This must be called with the session 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) { @@ -137,31 +185,28 @@ 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); - rcu_read_lock(); consumer_destroy_output(session->consumer); - rcu_read_unlock(); + 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; @@ -170,33 +215,36 @@ int session_create(char *name, char *path, uid_t uid, gid_t gid) 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; + 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; } - new_session->start_consumer = 1; - } else { - /* No path indicates that there is no use for a consumer. */ - new_session->start_consumer = 0; - new_session->path[0] = '\0'; } /* Init kernel session */ @@ -209,17 +257,10 @@ int session_create(char *name, char *path, uid_t uid, gid_t gid) new_session->uid = uid; new_session->gid = gid; - /* Mkdir if we have a valid path and length */ - if (strlen(new_session->path) > 0) { - ret = run_as_mkdir_recursive(new_session->path, S_IRWXU | S_IRWXG, - new_session->uid, new_session->gid); - if (ret < 0) { - if (ret != -EEXIST) { - ERR("Trace directory creation error"); - ret = LTTCOMM_CREATE_DIR_FAIL; - goto error; - } - } + ret = snapshot_init(&new_session->snapshot); + if (ret < 0) { + ret = LTTNG_ERR_NOMEM; + goto error; } /* Add new session to the session list */ @@ -232,17 +273,30 @@ int session_create(char *name, char *path, uid_t uid, gid_t gid) * up and, if valid, assign it to the session. */ - 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); + 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_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; + } +}