-static int
-extract_header_length(u_int16_t fc)
-{
- int len = 0;
-
- switch ((fc >> 10) & 0x3) {
- case 0x00:
- if (fc & (1 << 6)) /* intra-PAN with none dest addr */
- return -1;
- break;
- case 0x01:
- return -1;
- case 0x02:
- len += 4;
- break;
- case 0x03:
- len += 10;
- break;
- }
-
- switch ((fc >> 14) & 0x3) {
- case 0x00:
- break;
- case 0x01:
- return -1;
- case 0x02:
- len += 4;
- break;
- case 0x03:
- len += 10;
- break;
- }
-
- if (fc & (1 << 6)) {
- if (len < 2)
- return -1;
- len -= 2;
- }
-
- return len;
-}
-
+/*
+ * Frame Control subfields.
+ */
+#define FC_FRAME_TYPE(fc) ((fc) & 0x7)
+#define FC_SECURITY_ENABLED 0x0008
+#define FC_FRAME_PENDING 0x0010
+#define FC_ACK_REQUEST 0x0020
+#define FC_PAN_ID_COMPRESSION 0x0040
+#define FC_DEST_ADDRESSING_MODE(fc) (((fc) >> 10) & 0x3)
+#define FC_FRAME_VERSION(fc) (((fc) >> 12) & 0x3)
+#define FC_SRC_ADDRESSING_MODE(fc) (((fc) >> 14) & 0x3)
+
+#define FC_ADDRESSING_MODE_NONE 0x00
+#define FC_ADDRESSING_MODE_RESERVED 0x01
+#define FC_ADDRESSING_MODE_SHORT 0x02
+#define FC_ADDRESSING_MODE_LONG 0x03