all: use nm_utils_uid_to_name() instead of getpwuid()

We shouldn't use non-threadsafe API. We don't really know what
other threads (e.g. GDBus' helper thread or GResolver) are doing.

clients/common/nm-polkit-listener.c

@@ -164,20 +164,14 @@ auth_request_complete (AuthRequest *request, gboolean success)
 
 static gboolean
 uid_to_name (uid_t uid,
-             const char **out_name)
+             gboolean *out_cached,
+             char **out_name)
 {
-	const struct passwd *passwd;
-
-	if (*out_name)
-		return TRUE;
-
-	passwd = getpwuid (uid);
-	if (   !passwd
-	    || !passwd->pw_name)
-		return FALSE;
-
-	*out_name = passwd->pw_name;
-	return TRUE;
+	if (!*out_cached) {
+		*out_cached = TRUE;
+		*out_name = nm_utils_uid_to_name (uid);
+	}
+	return !!(*out_name);
 }
 
 static char *
@@ -205,17 +199,18 @@ choose_identity (GVariant *identities)
 			v = g_variant_lookup_value (details, "uid", G_VARIANT_TYPE_UINT32);
 			if (v) {
 				guint32 uid = g_variant_get_uint32 (v);
-				const char *u = NULL;
+				gs_free char *u = NULL;
+				gboolean cached = FALSE;
 
 				if (user) {
-					if (!uid_to_name (uid, &u))
+					if (!uid_to_name (uid, &cached, &u))
 						continue;
 					if (nm_streq (u, user))
-						return g_strdup (user);
+						return g_steal_pointer (&u);
 				}
 				if (   !username_root
 				    && uid == 0) {
-					if (!uid_to_name (uid, &u))
+					if (!uid_to_name (uid, &cached, &u))
 						continue;
 					username_root = g_strdup (u);
 					if (!user)
@@ -223,7 +218,7 @@ choose_identity (GVariant *identities)
 				}
 				if (   !username_root
 				    && !username_first) {
-					if (!uid_to_name (uid, &u))
+					if (!uid_to_name (uid, &cached, &u))
 						continue;
 					username_first = g_strdup (u);
 				}

src/nm-auth-utils.c

@@ -618,7 +618,7 @@ nm_auth_is_subject_in_acl (NMConnection *connection,
                            char **out_error_desc)
 {
 	NMSettingConnection *s_con;
-	const char *user = NULL;
+	gs_free char *user = NULL;
 	gulong uid;
 
 	g_return_val_if_fail (connection, FALSE);
@@ -635,7 +635,8 @@ nm_auth_is_subject_in_acl (NMConnection *connection,
 	if (0 == uid)
 		return TRUE;
 
-	if (!nm_session_monitor_uid_to_user (uid, &user)) {
+	user = nm_utils_uid_to_name (uid);
+	if (!user) {
 		NM_SET_OUT (out_error_desc,
 		            g_strdup_printf ("Could not determine username for uid %lu", uid));
 		return FALSE;

src/nm-session-monitor.c

@@ -280,28 +280,6 @@ ck_finalize (NMSessionMonitor *monitor)
 
 NM_DEFINE_SINGLETON_GETTER (NMSessionMonitor, nm_session_monitor_get, NM_TYPE_SESSION_MONITOR);
 
-/**
- * nm_session_monitor_uid_to_user:
- * @uid: UID.
- * @out_user: Return location for user name.
- *
- * Translates a UID to a user name.
- */
-gboolean
-nm_session_monitor_uid_to_user (uid_t uid, const char **out_user)
-{
-	struct passwd *pw = getpwuid (uid);
-
-	g_assert (out_user);
-
-	if (!pw)
-		return FALSE;
-
-	*out_user = pw->pw_name;
-
-	return TRUE;
-}
-
 /**
  * nm_session_monitor_user_to_uid:
  * @user: User naee.

src/nm-session-monitor.h

@@ -23,7 +23,6 @@ GType nm_session_monitor_get_type (void) G_GNUC_CONST;
 
 NMSessionMonitor *nm_session_monitor_get (void);
 
-gboolean nm_session_monitor_uid_to_user    (uid_t uid, const char **out_user);
 gboolean nm_session_monitor_user_to_uid    (const char *user, uid_t *out_uid);
 gboolean nm_session_monitor_session_exists (NMSessionMonitor *self,
                                             uid_t uid,

src/settings/nm-agent-manager.c

@@ -869,8 +869,7 @@ _con_get_request_done (NMSecretAgent *agent,
 	Request *req = user_data;
 	GVariant *setting_secrets;
 	const char *agent_dbus_owner;
-	struct passwd *pw;
-	char *agent_uname = NULL;
+	gs_free char *agent_name = NULL;
 
 	g_return_if_fail (call_id == req->current_call_id);
 	g_return_if_fail (agent == req->current);
@@ -921,17 +920,16 @@ _con_get_request_done (NMSecretAgent *agent,
 	_LOGD (agent, "agent returned secrets for request "LOG_REQ_FMT,
 	       LOG_REQ_ARG (req));
 
-	/* Get the agent's username */
-	pw = getpwuid (nm_secret_agent_get_owner_uid (agent));
-	if (pw && strlen (pw->pw_name)) {
+	agent_name = nm_utils_uid_to_name (nm_secret_agent_get_owner_uid (agent));
+	if (   agent_name
+	    && !g_utf8_validate (agent_name, -1, NULL)) {
 		/* Needs to be UTF-8 valid since it may be pushed through D-Bus */
-		if (g_utf8_validate (pw->pw_name, -1, NULL))
-			agent_uname = g_strdup (pw->pw_name);
+		nm_clear_g_free (&agent_name);
 	}
 
 	agent_dbus_owner = nm_secret_agent_get_dbus_owner (agent);
-	req_complete (req, secrets, agent_dbus_owner, agent_uname, NULL);
-	g_free (agent_uname);
+
+	req_complete (req, secrets, agent_dbus_owner, agent_name, NULL);
 }
 
 static void

src/settings/nm-secret-agent.c

@@ -695,8 +695,7 @@ nm_secret_agent_new (GDBusMethodInvocation *context,
 	NMSecretAgent *self;
 	NMSecretAgentPrivate *priv;
 	const char *dbus_owner;
-	struct passwd *pw;
-	char *owner_username = NULL;
+	gs_free char *owner_username = NULL;
 	char *description = NULL;
 	char buf_subject[64];
 	char buf_caps[150];
@@ -715,9 +714,7 @@ nm_secret_agent_new (GDBusMethodInvocation *context,
 
 	uid = nm_auth_subject_get_unix_process_uid (subject);
 
-	pw = getpwuid (uid);
-	if (pw && pw->pw_name && pw->pw_name[0])
-		owner_username = g_strdup (pw->pw_name);
+	owner_username = nm_utils_uid_to_name (uid);
 
 	dbus_owner = nm_auth_subject_get_unix_process_dbus_sender (subject);
 
@@ -735,7 +732,7 @@ nm_secret_agent_new (GDBusMethodInvocation *context,
 	       _capabilities_to_string (capabilities, buf_caps, sizeof (buf_caps)));
 
 	priv->identifier = g_strdup (identifier);
-	priv->owner_username = owner_username;
+	priv->owner_username = g_steal_pointer (&owner_username);
 	priv->dbus_owner = g_strdup (dbus_owner);
 	priv->description = description;
 	priv->capabilities = capabilities;