Add some inline functions to test the presence of optional 802.11

header fields (Sequence Control, Address 4, QoS Control, +HTC) and
use them where appropriate.

Add ieee80211_get_qos() inline function to extract the QoS control
field of an 802.11 header instead of duplicating the same scary
code everywhere (the location of this field depends on the presence
of an Address 4 field).

Export ieee80211_up_to_ac() so that drivers can select the access
category to use based on the TID subfield of the QoS Control field.

Define more QoS-related bits for the RSN Capabilities field of RSN IE
(will be used later).

1 files changed, 17 insertions, 32 deletions

diff --git a/sys/net80211/ieee80211_input.c b/sys/net80211/ieee80211_input.c
index a98174527c0..38428f009a0 100644
--- a/sys/net80211/ieee80211_input.c
+++ b/sys/net80211/ieee80211_input.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: ieee80211_input.c,v 1.104 2008/09/01 19:41:10 damien Exp $	*/
+/*	$OpenBSD: ieee80211_input.c,v 1.105 2008/09/27 15:00:08 damien Exp $	*/
 
 /*-
  * Copyright (c) 2001 Atsushi Onoe
@@ -102,24 +102,19 @@ void	ieee80211_recv_action(struct ieee80211com *, struct mbuf *,
  * Retrieve the length in bytes of a 802.11 header.
  */
 u_int
-ieee80211_get_hdrlen(const void *data)
+ieee80211_get_hdrlen(const struct ieee80211_frame *wh)
 {
-	const u_int8_t *fc = data;
-	u_int size = sizeof(struct ieee80211_frame);
-
-	/* NB: doesn't work with control frames */
-	KASSERT((fc[0] & IEEE80211_FC0_TYPE_MASK) != IEEE80211_FC0_TYPE_CTL);
-
-	if ((fc[1] & IEEE80211_FC1_DIR_MASK) == IEEE80211_FC1_DIR_DSTODS)
-		size += IEEE80211_ADDR_LEN;		/* i_addr4 */
-	if ((fc[0] & (IEEE80211_FC0_TYPE_MASK | IEEE80211_FC0_SUBTYPE_QOS)) ==
-	    (IEEE80211_FC0_TYPE_DATA | IEEE80211_FC0_SUBTYPE_QOS)) {
-		size += sizeof(u_int16_t);		/* i_qos */
-		if (fc[1] & IEEE80211_FC1_ORDER)
-			size += sizeof(u_int32_t);	/* i_ht */
-	} else if ((fc[0] & IEEE80211_FC0_TYPE_MASK) ==
-	     IEEE80211_FC0_TYPE_MGT && (fc[1] & IEEE80211_FC1_ORDER))
-		size += sizeof(u_int32_t);		/* i_ht */
+	u_int size = sizeof(*wh);
+
+	/* NB: does not work with control frames */
+	KASSERT(ieee80211_has_seq(wh));
+
+	if (ieee80211_has_addr4(wh))
+		size += IEEE80211_ADDR_LEN;	/* i_addr4 */
+	if (ieee80211_has_qos(wh))
+		size += sizeof(u_int16_t);	/* i_qos */
+	if (ieee80211_has_htc(wh))
+		size += sizeof(u_int32_t);	/* i_ht */
 	return size;
 }
 
@@ -181,22 +176,12 @@ ieee80211_input(struct ifnet *ifp, struct mbuf *m, struct ieee80211_node *ni,
 		}
 	}
 	/* check and save sequence control field, if present */
-	if (ic->ic_state != IEEE80211_S_SCAN &&
-	    type != IEEE80211_FC0_TYPE_CTL) {
+	if (ieee80211_has_seq(wh) &&
+	    ic->ic_state != IEEE80211_S_SCAN) {
 		nrxseq = letoh16(*(u_int16_t *)wh->i_seq) >>
 		    IEEE80211_SEQ_SEQ_SHIFT;
-		if ((wh->i_fc[0] &
-		    (IEEE80211_FC0_TYPE_MASK | IEEE80211_FC0_SUBTYPE_QOS)) ==
-		    (IEEE80211_FC0_TYPE_DATA | IEEE80211_FC0_SUBTYPE_QOS)) {
-			if (dir == IEEE80211_FC1_DIR_DSTODS) {
-				struct ieee80211_qosframe_addr4 *qwh4 =
-				    (struct ieee80211_qosframe_addr4 *)wh;
-				tid = qwh4->i_qos[0] & 0x0f;
-			} else {
-				struct ieee80211_qosframe *qwh =
-				    (struct ieee80211_qosframe *)wh;
-				tid = qwh->i_qos[0] & 0x0f;
-			}
+		if (ieee80211_has_qos(wh)) {
+			tid = ieee80211_get_qos(wh) & IEEE80211_QOS_TID;
 			orxseq = &ni->ni_qos_rxseqs[tid];
 		} else
 			orxseq = &ni->ni_rxseq;