"Data", /* 1 */
"ACK", /* 2 */
"Command", /* 3 */
- "Reserved", /* 4 */
- "Reserved", /* 5 */
- "Reserved", /* 6 */
- "Reserved", /* 7 */
+ "Reserved (0x4)", /* 4 */
+ "Reserved (0x5)", /* 5 */
+ "Reserved (0x6)", /* 6 */
+ "Reserved (0x7)", /* 7 */
};
-static int
-extract_header_length(uint16_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
u_int
ieee802_15_4_if_print(netdissect_options *ndo,
const struct pcap_pkthdr *h, const u_char *p)
{
u_int caplen = h->caplen;
- int hdrlen;
+ u_int hdrlen;
uint16_t fc;
uint8_t seq;
+ uint16_t panid = 0;
if (caplen < 3) {
- ND_PRINT((ndo, "[|802.15.4] %x", caplen));
+ ND_PRINT((ndo, "[|802.15.4]"));
return caplen;
}
+ hdrlen = 3;
fc = EXTRACT_LE_16BITS(p);
- hdrlen = extract_header_length(fc);
-
seq = EXTRACT_LE_8BITS(p + 2);
p += 3;
caplen -= 3;
- ND_PRINT((ndo,"IEEE 802.15.4 %s packet ", ftypes[fc & 0x7]));
+ ND_PRINT((ndo,"IEEE 802.15.4 %s packet ", ftypes[FC_FRAME_TYPE(fc)]));
if (ndo->ndo_vflag)
ND_PRINT((ndo,"seq %02x ", seq));
- if (hdrlen == -1) {
- ND_PRINT((ndo,"invalid! "));
- return caplen;
- }
-
-
- if (!ndo->ndo_vflag) {
- p+= hdrlen;
- caplen -= hdrlen;
- } else {
- uint16_t panid = 0;
- switch ((fc >> 10) & 0x3) {
- case 0x00:
+ /*
+ * Destination address and PAN ID, if present.
+ */
+ switch (FC_DEST_ADDRESSING_MODE(fc)) {
+ case FC_ADDRESSING_MODE_NONE:
+ if (fc & FC_PAN_ID_COMPRESSION) {
+ /*
+ * PAN ID compression; this requires that both
+ * the source and destination addresses be present,
+ * but the destination address is missing.
+ */
+ ND_PRINT((ndo, "[|802.15.4]"));
+ return hdrlen;
+ }
+ if (ndo->ndo_vflag)
ND_PRINT((ndo,"none "));
- break;
- case 0x01:
+ break;
+ case FC_ADDRESSING_MODE_RESERVED:
+ if (ndo->ndo_vflag)
ND_PRINT((ndo,"reserved destination addressing mode"));
- return 0;
- case 0x02:
- panid = EXTRACT_LE_16BITS(p);
- p += 2;
- ND_PRINT((ndo,"%04x:%04x ", panid, EXTRACT_LE_16BITS(p)));
- p += 2;
- break;
- case 0x03:
- panid = EXTRACT_LE_16BITS(p);
- p += 2;
- ND_PRINT((ndo,"%04x:%s ", panid, le64addr_string(ndo, p)));
- p += 8;
- break;
+ return hdrlen;
+ case FC_ADDRESSING_MODE_SHORT:
+ if (caplen < 2) {
+ ND_PRINT((ndo, "[|802.15.4]"));
+ return hdrlen;
+ }
+ panid = EXTRACT_LE_16BITS(p);
+ p += 2;
+ caplen -= 2;
+ hdrlen += 2;
+ if (caplen < 2) {
+ ND_PRINT((ndo, "[|802.15.4]"));
+ return hdrlen;
}
+ if (ndo->ndo_vflag)
+ ND_PRINT((ndo,"%04x:%04x ", panid, EXTRACT_LE_16BITS(p + 2)));
+ p += 2;
+ caplen -= 2;
+ hdrlen += 2;
+ break;
+ case FC_ADDRESSING_MODE_LONG:
+ if (caplen < 2) {
+ ND_PRINT((ndo, "[|802.15.4]"));
+ return hdrlen;
+ }
+ panid = EXTRACT_LE_16BITS(p);
+ p += 2;
+ caplen -= 2;
+ hdrlen += 2;
+ if (caplen < 8) {
+ ND_PRINT((ndo, "[|802.15.4]"));
+ return hdrlen;
+ }
+ if (ndo->ndo_vflag)
+ ND_PRINT((ndo,"%04x:%s ", panid, le64addr_string(ndo, p + 2)));
+ p += 8;
+ caplen -= 8;
+ hdrlen += 8;
+ break;
+ }
+ if (ndo->ndo_vflag)
ND_PRINT((ndo,"< "));
- switch ((fc >> 14) & 0x3) {
- case 0x00:
+ /*
+ * Source address and PAN ID, if present.
+ */
+ switch (FC_SRC_ADDRESSING_MODE(fc)) {
+ case FC_ADDRESSING_MODE_NONE:
+ if (ndo->ndo_vflag)
ND_PRINT((ndo,"none "));
- break;
- case 0x01:
+ break;
+ case FC_ADDRESSING_MODE_RESERVED:
+ if (ndo->ndo_vflag)
ND_PRINT((ndo,"reserved source addressing mode"));
- return 0;
- case 0x02:
- if (!(fc & (1 << 6))) {
- panid = EXTRACT_LE_16BITS(p);
- p += 2;
+ return 0;
+ case FC_ADDRESSING_MODE_SHORT:
+ if (!(fc & FC_PAN_ID_COMPRESSION)) {
+ /*
+ * The source PAN ID is not compressed out, so
+ * fetch it. (Otherwise, we'll use the destination
+ * PAN ID, fetched above.)
+ */
+ if (caplen < 2) {
+ ND_PRINT((ndo, "[|802.15.4]"));
+ return hdrlen;
}
- ND_PRINT((ndo,"%04x:%04x ", panid, EXTRACT_LE_16BITS(p)));
+ panid = EXTRACT_LE_16BITS(p);
p += 2;
- break;
- case 0x03:
- if (!(fc & (1 << 6))) {
- panid = EXTRACT_LE_16BITS(p);
- p += 2;
+ caplen -= 2;
+ hdrlen += 2;
+ }
+ if (caplen < 2) {
+ ND_PRINT((ndo, "[|802.15.4]"));
+ return hdrlen;
+ }
+ if (ndo->ndo_vflag)
+ ND_PRINT((ndo,"%04x:%04x ", panid, EXTRACT_LE_16BITS(p)));
+ p += 2;
+ caplen -= 2;
+ hdrlen += 2;
+ break;
+ case FC_ADDRESSING_MODE_LONG:
+ if (!(fc & FC_PAN_ID_COMPRESSION)) {
+ /*
+ * The source PAN ID is not compressed out, so
+ * fetch it. (Otherwise, we'll use the destination
+ * PAN ID, fetched above.)
+ */
+ if (caplen < 2) {
+ ND_PRINT((ndo, "[|802.15.4]"));
+ return hdrlen;
}
- ND_PRINT((ndo,"%04x:%s ", panid, le64addr_string(ndo, p)));
- p += 8;
- break;
+ panid = EXTRACT_LE_16BITS(p);
+ p += 2;
+ caplen -= 2;
+ hdrlen += 2;
}
-
- caplen -= hdrlen;
+ if (caplen < 8) {
+ ND_PRINT((ndo, "[|802.15.4]"));
+ return hdrlen;
+ }
+ if (ndo->ndo_vflag)
+ ND_PRINT((ndo,"%04x:%s ", panid, le64addr_string(ndo, p)));
+ p += 8;
+ caplen -= 8;
+ hdrlen += 8;
+ break;
}
if (!ndo->ndo_suppress_default_print)
ND_DEFAULTPRINT(p, caplen);
- return 0;
+ return hdrlen;
}