This matters for frames which arrived in A-MPDUs.
Before:
12:35:07.726898 802.11: QoS data: 00:1e:52:f1:80:55 sap 00 > 58:94:6b:06:70:04
sap 06 I (s=85,r=85,C) len=82
After:
12:49:08.879003 802.11: QoS data: 10.197.84.33 > 10.0.1.3: icmp: echo reply
Index: print-802_11.c
===================================================================
RCS file: /cvs/src/usr.sbin/tcpdump/print-802_11.c,v
retrieving revision 1.28
diff -u -p -r1.28 print-802_11.c
--- print-802_11.c 12 Jan 2016 09:28:10 -0000 1.28
+++ print-802_11.c 31 Jan 2016 11:48:06 -0000
@@ -156,11 +156,19 @@ ieee80211_data(struct ieee80211_frame *w
struct ieee80211_frame_addr4 *w4;
u_int datalen;
int data = !(wh->i_fc[0] & IEEE80211_FC0_SUBTYPE_NODATA);
+ int hasqos = ((wh->i_fc[0] &
+ (IEEE80211_FC0_TYPE_MASK | IEEE80211_FC0_SUBTYPE_QOS)) ==
+ (IEEE80211_FC0_TYPE_DATA | IEEE80211_FC0_SUBTYPE_QOS));
u_char *esrc = NULL, *edst = NULL;
TCHECK(*wh);
- t += sizeof(struct ieee80211_frame);
- datalen = len - sizeof(struct ieee80211_frame);
+ if (hasqos) {
+ t += sizeof(struct ieee80211_qosframe);
+ datalen = len - sizeof(struct ieee80211_qosframe);
+ } else {
+ t += sizeof(struct ieee80211_frame);
+ datalen = len - sizeof(struct ieee80211_frame);
+ }
switch (wh->i_fc[1] & IEEE80211_FC1_DIR_MASK) {
case IEEE80211_FC1_DIR_TODS:
