3 files changed, 5 insertions, 5 deletions
diff --git a/src/config.y b/src/config.y
index deaa100..55d0e94 100644
--- a/src/config.y
+++ b/src/config.y
@@ -311,7 +311,7 @@ bind_default:
 	;
 
 mtu:		TOK_UINT {
-			if ($1 > 65535) {
+			if (conf->mtu < 576 || $1 > 65535) {
 				fastd_config_error(&@$, ctx, conf, filename, depth, "invalid MTU");
 				YYERROR;
 			}
@@ -544,7 +544,7 @@ colon_or_port:	':'
 	;
 
 port:		colon_or_port TOK_UINT {
-			if ($2 > 65535) {
+			if ($2 < 1 || $2 > 65535) {
 				fastd_config_error(&@$, ctx, conf, filename, depth, "invalid port");
 				YYERROR;
 			}
diff --git a/src/options.c b/src/options.c
index aba6bd6..7bab8bc 100644
--- a/src/options.c
+++ b/src/options.c
@@ -151,7 +151,7 @@ static void option_mtu(fastd_context_t *ctx, fastd_config_t *conf, const char *a
 	char *endptr;
 
 	conf->mtu = strtol(arg, &endptr, 10);
-	if (*endptr || conf->mtu < 576)
+	if (*endptr || conf->mtu < 576 || conf->mtu > 65535)
 		exit_error(ctx, "invalid mtu `%s'", arg);
 }
 
@@ -185,7 +185,7 @@ static void option_bind(fastd_context_t *ctx, fastd_config_t *conf, const char *
 
 	if (charptr) {
 		l = strtol(charptr+1, &endptr, 10);
-		if (*endptr || l < 0 || l > 65535)
+		if (*endptr || l < 1 || l > 65535)
 			exit_error(ctx, "invalid bind port `%s'", charptr+1);
 	}
 	else {
diff --git a/src/options.def.h b/src/options.def.h
index 42e6d6f..dfb4983 100644
--- a/src/options.def.h
+++ b/src/options.def.h
@@ -15,7 +15,7 @@ OPTION_ARG(option_config_peer_dir, "--config-peer-dir", "<dir>", "Loads all file
 OPTION_ARG(option_mode, "--mode" OR "-m", "tap|tun", "Sets the mode of the interface");
 OPTION_ARG(option_interface, "--interface" OR "-i", "<name>", "Sets the name of the TUN/TAP interface to use");
 OPTION_ARG(option_mtu, "--mtu" OR "-M", "<mtu>", "Sets the MTU; must be at least 576");
-OPTION_ARG(option_bind, "--bind" OR "-b", "<address>:<port>", "Sets the bind address");
+OPTION_ARG(option_bind, "--bind" OR "-b", "<address>[:<port>]", "Sets the bind address");
 OPTION_ARG(option_protocol, "--protocol" OR "-p", "<protocol>", "Sets the protocol");
 OPTION_ARG(option_method, "--method", "<method>", "Sets the encryption method");
 OPTION(option_forward, "--forward", "Enables forwarding of packets between peers; read the documentation before use!");