Restrict "node_name" to maximum 63 characters

In "recovery.conf", the configuration parameter "node_name" is used
as the "application_name" value, which will be truncated by PostgreSQL
to 63 characters (NAMEDATALEN - 1).

repmgr sometimes needs to be able to extract the application name from
pg_stat_replication to determine if a node is connected (e.g. when
executing "repmgr standby register"), so the comparison will fail
if "node_name" exceeds 63 characters.

configfile.c

@@ -484,7 +484,14 @@ _parse_config(t_configuration_options *options, ItemList *error_list, ItemList *
 			node_id_found = true;
 		}
 		else if (strcmp(name, "node_name") == 0)
-			strncpy(options->node_name, value, MAXLEN);
+		{
+			if (strlen(value) < sizeof(options->node_name))
+				strncpy(options->node_name, value, sizeof(options->node_name));
+			else
+				item_list_append_format(error_list,
+										_("value for \"node_name\" must contain fewer than %lu characters"),
+										sizeof(options->node_name));
+		}
 		else if (strcmp(name, "conninfo") == 0)
 			strncpy(options->conninfo, value, MAXLEN);
 		else if (strcmp(name, "data_directory") == 0)
@@ -494,11 +501,12 @@ _parse_config(t_configuration_options *options, ItemList *error_list, ItemList *
 
 		else if (strcmp(name, "replication_user") == 0)
 		{
-			if (strlen(value) < NAMEDATALEN)
-				strncpy(options->replication_user, value, NAMEDATALEN);
+			if (strlen(value) < sizeof(options->replication_user))
+				strncpy(options->replication_user, value, sizeof(options->replication_user));
 			else
-				item_list_append(error_list,
-								 _("value for \"replication_user\" must contain fewer than " STR(NAMEDATALEN) " characters"));
+				item_list_append_format(error_list,
+										_("value for \"replication_user\" must contain fewer than %lu characters"),
+										sizeof(options->replication_user));
 		}
 		else if (strcmp(name, "pg_bindir") == 0)
 			strncpy(options->pg_bindir, value, MAXPGPATH);
@@ -1196,7 +1204,7 @@ reload_config(t_configuration_options *orig_options, t_server_type server_type)
 		return false;
 	}
 
-	if (strncmp(new_options.node_name, orig_options->node_name, MAXLEN) != 0)
+	if (strncmp(new_options.node_name, orig_options->node_name, sizeof(orig_options->node_name)) != 0)
 	{
 		log_warning(_("\"node_name\" cannot be changed, keeping current configuration"));
 		return false;

configfile.h

@@ -76,7 +76,7 @@ typedef struct
 {
 	/* node information */
 	int			node_id;
-	char		node_name[MAXLEN];
+	char		node_name[NAMEDATALEN];
 	char		conninfo[MAXLEN];
 	char		replication_user[NAMEDATALEN];
 	char		data_directory[MAXPGPATH];

dbutils.c

@@ -2201,9 +2201,9 @@ _populate_node_record(PGresult *res, t_node_info *node_info, int row, bool init_
 		node_info->upstream_node_id = atoi(PQgetvalue(res, row, 2));
 	}
 
-	strncpy(node_info->node_name, PQgetvalue(res, row, 3), MAXLEN);
+	strncpy(node_info->node_name, PQgetvalue(res, row, 3), sizeof(node_info->node_name));
 	strncpy(node_info->conninfo, PQgetvalue(res, row, 4), MAXLEN);
-	strncpy(node_info->repluser, PQgetvalue(res, row, 5), NAMEDATALEN);
+	strncpy(node_info->repluser, PQgetvalue(res, row, 5), sizeof(node_info->repluser));
 	strncpy(node_info->slot_name, PQgetvalue(res, row, 6), MAXLEN);
 	strncpy(node_info->location, PQgetvalue(res, row, 7), MAXLEN);
 	node_info->priority = atoi(PQgetvalue(res, row, 8));
@@ -2211,7 +2211,7 @@ _populate_node_record(PGresult *res, t_node_info *node_info, int row, bool init_
 	strncpy(node_info->config_file, PQgetvalue(res, row, 10), MAXPGPATH);
 
 	/* This won't normally be set */
-	strncpy(node_info->upstream_node_name, PQgetvalue(res, row, 11), MAXLEN);
+	strncpy(node_info->upstream_node_name, PQgetvalue(res, row, 11), sizeof(node_info->upstream_node_name));
 
 	/* Set remaining struct fields with default values */
 
@@ -5771,7 +5771,7 @@ get_bdr_other_node_name(PGconn *conn, int node_id, char *node_name)
 
 	if (PQresultStatus(res) == PGRES_TUPLES_OK)
 	{
-		strncpy(node_name, PQgetvalue(res, 0, 0), MAXLEN);
+		strncpy(node_name, PQgetvalue(res, 0, 0), NAMEDATALEN);
 	}
 	else
 	{

dbutils.h

@@ -134,8 +134,8 @@ typedef struct s_node_info
 	int			node_id;
 	int			upstream_node_id;
 	t_server_type type;
-	char		node_name[MAXLEN];
-	char		upstream_node_name[MAXLEN];
+	char		node_name[NAMEDATALEN];
+	char		upstream_node_name[NAMEDATALEN];
 	char		conninfo[MAXLEN];
 	char		repluser[NAMEDATALEN];
 	char		location[MAXLEN];

doc/configuration-file-required-settings.sgml

@@ -39,6 +39,9 @@
        called <varname>standby1</varname> (for example), things will be confusing
        to say the least.
      </para>
+     <para>
+       Maximum length is 63 characters.
+     </para>
     </listitem>
    </varlistentry>
 

repmgr-action-cluster.c

@@ -1063,7 +1063,9 @@ build_cluster_matrix(t_node_matrix_rec ***matrix_rec_dest, int *name_length, Ite
 		matrix_rec_list[i] = (t_node_matrix_rec *) pg_malloc0(sizeof(t_node_matrix_rec));
 
 		matrix_rec_list[i]->node_id = cell->node_info->node_id;
-		strncpy(matrix_rec_list[i]->node_name, cell->node_info->node_name, MAXLEN);
+		strncpy(matrix_rec_list[i]->node_name,
+				cell->node_info->node_name,
+				sizeof(cell->node_info->node_name));
 
 		/*
 		 * Find the maximum length of a node name
@@ -1278,7 +1280,7 @@ build_cluster_crosscheck(t_node_status_cube ***dest_cube, int *name_length, Item
 
 		cube[h] = (t_node_status_cube *) pg_malloc(sizeof(t_node_status_cube));
 		cube[h]->node_id = cell->node_info->node_id;
-		strncpy(cube[h]->node_name, cell->node_info->node_name, MAXLEN);
+		strncpy(cube[h]->node_name, cell->node_info->node_name, sizeof(cell->node_info->node_name));
 
 		/*
 		 * Find the maximum length of a node name

repmgr-action-cluster.h

@@ -30,14 +30,14 @@ typedef struct
 typedef struct
 {
 	int			node_id;
-	char		node_name[MAXLEN];
+	char		node_name[NAMEDATALEN];
 	t_node_status_rec **node_status_list;
 } t_node_matrix_rec;
 
 typedef struct
 {
 	int			node_id;
-	char		node_name[MAXLEN];
+	char		node_name[NAMEDATALEN];
 	t_node_matrix_rec **matrix_list_rec;
 } t_node_status_cube;
 

repmgr-action-standby.c

@@ -213,7 +213,7 @@ do_standby_clone(void)
 		param_set(&recovery_conninfo, "application_name", config_file_options.node_name);
 
 		get_conninfo_value(config_file_options.conninfo, "application_name", application_name);
-		if (strlen(application_name) && strncmp(application_name, config_file_options.node_name, MAXLEN) != 0)
+		if (strlen(application_name) && strncmp(application_name, config_file_options.node_name, sizeof(config_file_options.node_name)) != 0)
 		{
 			log_notice(_("\"application_name\" is set in repmgr.conf but will be replaced by the node name"));
 		}

repmgr-client-global.h

@@ -70,7 +70,7 @@ typedef struct
 
 	/* general node options */
 	int			node_id;
-	char		node_name[MAXLEN];
+	char		node_name[NAMEDATALEN];
 	char		data_dir[MAXPGPATH];
 	int			remote_node_id;
 

repmgr-client.c

@@ -356,9 +356,15 @@ main(int argc, char **argv)
 
 				/* --node-name */
 			case OPT_NODE_NAME:
-				strncpy(runtime_options.node_name, optarg, MAXLEN);
+			{
+				if (strlen(optarg) < sizeof(runtime_options.node_name))
+					strncpy(runtime_options.node_name, optarg, sizeof(runtime_options.node_name));
+				else
+					item_list_append_format(&cli_errors,
+											_("value for \"--node-name\" must contain fewer than %lu characters"),
+											sizeof(runtime_options.node_name));
 				break;
-
+			}
 				/* --remote-node-id */
 			case OPT_REMOTE_NODE_ID:
 				runtime_options.remote_node_id = repmgr_atoi(optarg, "--remote-node-id", &cli_errors, MIN_NODE_ID);
@@ -3001,7 +3007,7 @@ init_node_record(t_node_info *node_record)
 		strncpy(node_record->location, "default", MAXLEN);
 
 
-	strncpy(node_record->node_name, config_file_options.node_name, MAXLEN);
+	strncpy(node_record->node_name, config_file_options.node_name, sizeof(node_record->node_name));
 	strncpy(node_record->conninfo, config_file_options.conninfo, MAXLEN);
 	strncpy(node_record->config_file, config_file_path, MAXPGPATH);
 

repmgr.conf.sample

@@ -28,6 +28,7 @@
 				 # node's current role, e.g. 'primary' or 'standby1',
 				 # as roles can change and it will be confusing if
 				 # the current primary is called 'standby1'.
+                                 # Maximum length is 63 characters.
 
 #conninfo=''			 # Database connection information as a conninfo string.
 				 # All servers in the cluster must be able to connect to