[src/trunk]: src/sys/net80211 802.11 Control/multicast/broadcast packets are ...

[dyoung <dyoung%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/e3b325dc94fc
branches:  trunk
changeset: 572247:e3b325dc94fc
user:      dyoung <dyoung%NetBSD.org@localhost>
date:      Mon Dec 27 09:25:05 2004 +0000

description:
802.11 Control/multicast/broadcast packets are not acknowledged.
Set a shorter 802.11 Duration field, accordingly.

XXX We expect CTS/ACK at 1 Mb/s for 1 & 2 Mb/s stations; and CTS/ACK
at 2 Mb/s for 5.5 & 11 Mb/s stations.  We need to check with the
802.11 standard.  Rate negotiation may need to be overhauld for
standards compliance, too.

diffstat:

 sys/net80211/ieee80211_output.c |  27 +++++++++++++++++----------
 1 files changed, 17 insertions(+), 10 deletions(-)

diffs (83 lines):

diff -r 555c045002ed -r e3b325dc94fc sys/net80211/ieee80211_output.c
--- a/sys/net80211/ieee80211_output.c   Mon Dec 27 08:59:16 2004 +0000
+++ b/sys/net80211/ieee80211_output.c   Mon Dec 27 09:25:05 2004 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: ieee80211_output.c,v 1.22 2004/12/27 05:35:33 mycroft Exp $    */
+/*     $NetBSD: ieee80211_output.c,v 1.23 2004/12/27 09:25:05 dyoung Exp $     */
 /*-
  * Copyright (c) 2001 Atsushi Onoe
  * Copyright (c) 2002, 2003 Sam Leffler, Errno Consulting
@@ -35,7 +35,7 @@
 #ifdef __FreeBSD__
 __FBSDID("$FreeBSD: src/sys/net80211/ieee80211_output.c,v 1.10 2004/04/02 23:25:39 sam Exp $");
 #else
-__KERNEL_RCSID(0, "$NetBSD: ieee80211_output.c,v 1.22 2004/12/27 05:35:33 mycroft Exp $");
+__KERNEL_RCSID(0, "$NetBSD: ieee80211_output.c,v 1.23 2004/12/27 09:25:05 dyoung Exp $");
 #endif
 
 #include "opt_inet.h"
@@ -293,11 +293,11 @@
  *          residual octets at end of data slot
  */
 static int
-ieee80211_compute_duration1(int len, uint32_t flags, int rate,
+ieee80211_compute_duration1(int len, int use_ack, uint32_t flags, int rate,
     struct ieee80211_duration *d)
 {
        int pre, ctsrate;
-       int bitlen, data_dur, remainder;
+       int ack, bitlen, data_dur, remainder;
 
        /* RTS reserves medium for SIFS | CTS | SIFS | (DATA) | SIFS | ACK
         * DATA reserves medium for SIFS | ACK
@@ -344,13 +344,14 @@
 
        d->d_plcp_len = data_dur;
 
+       ack = (use_ack) ? pre + (IEEE80211_DUR_DS_SLOW_ACK * 2) / ctsrate : 0;
+
        d->d_rts_dur =
            pre + (IEEE80211_DUR_DS_SLOW_CTS * 2) / ctsrate +
            pre + data_dur +
-           pre + (IEEE80211_DUR_DS_SLOW_ACK * 2) / ctsrate;
+           ack;
 
-       d->d_data_dur =
-           pre + (IEEE80211_DUR_DS_SLOW_ACK * 2) / rate;
+       d->d_data_dur = ack;
 
        return 0;
 }
@@ -384,7 +385,7 @@
     uint32_t flags, int fraglen, int rate, struct ieee80211_duration *d0,
     struct ieee80211_duration *dn, int *npktp, int debug)
 {
-       int rc;
+       int ack, rc;
        int firstlen, hdrlen, lastlen, lastlen0, npkt, overlen, paylen;
 
        if ((wh->i_fc[1] & IEEE80211_FC1_DIR_MASK) == IEEE80211_FC1_DIR_DSTODS)
@@ -435,7 +436,12 @@
                    __func__, npkt, firstlen, lastlen0, lastlen, fraglen,
                    overlen, len, rate, flags);
        }
-       rc = ieee80211_compute_duration1(firstlen + hdrlen, flags, rate, d0);
+
+       ack = !IEEE80211_IS_MULTICAST(wh->i_addr1) &&
+           (wh->i_fc[1] & IEEE80211_FC0_TYPE_MASK) != IEEE80211_FC0_TYPE_CTL;
+
+       rc = ieee80211_compute_duration1(firstlen + hdrlen,
+           ack, flags, rate, d0);
        if (rc == -1)
                return rc;
 
@@ -443,7 +449,8 @@
                *dn = *d0;
                return 0;
        }
-       return ieee80211_compute_duration1(lastlen + hdrlen, flags, rate, dn);
+       return ieee80211_compute_duration1(lastlen + hdrlen, ack, flags, rate,
+           dn);
 }
 
 /*