diff --git a/openbsc/src/ipaccess/ipaccess-firmware.c b/openbsc/src/ipaccess/ipaccess-firmware.c
index 5df3a38..806e6be 100644
--- a/openbsc/src/ipaccess/ipaccess-firmware.c
+++ b/openbsc/src/ipaccess/ipaccess-firmware.c
@@ -35,11 +35,11 @@
 struct sdp_firmware {
 	char magic[4];
 	char more_magic[4];
-	unsigned int header_length;
-	unsigned int file_length;
+	u_int32_t header_length;
+	u_int32_t file_length;
 	char sw_part[20];
 	char text1[122];
-	unsigned int short part_length;
+	u_int16_t part_length;
 	/* stuff i don't know */
 } __attribute__((packed));