From 4da4785412451e2f2b1c75821beea64857c23771 Mon Sep 17 00:00:00 2001
From: cinap_lenrek <cinap_lenrek@gmx.de>
Date: Mon, 24 Jun 2013 22:47:07 +0200
Subject: [PATCH] wifi: signal ap deassociation to aux/wpa with a zero length
 read.

aux/wpa needs to reset its reply counter on deassociation to
properly restart key negotiation. we signal this with a zero
length read on the connections filtering for eapol protocol.
---
 sys/src/9/pc/wifi.c | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/sys/src/9/pc/wifi.c b/sys/src/9/pc/wifi.c
index a34ab39e9..2d7468115 100644
--- a/sys/src/9/pc/wifi.c
+++ b/sys/src/9/pc/wifi.c
@@ -346,6 +346,25 @@ recvbeacon(Wifi *, Wnode *wn, uchar *d, int len)
 	}
 }
 
+/* notify aux/wpa with a zero length write that we got deassociated from the ap */
+static void
+wifideassoc(Wifi *wifi)
+{
+	Ether *ether;
+	Netfile *f;
+	int i;
+
+	ether = wifi->ether;
+	for(i=0; i<ether->nfile; i++){
+		f = ether->f[i];
+		if(f == nil || f->in == nil || f->inuse == 0 || f->type != 0x888e)
+			continue;
+		if(wifi->debug)
+			print("#%d: wifideassoc: %#p\n", ether->ctlrno, f);
+		qwrite(f->in, 0, 0);
+	}
+}
+
 /* check if a node qualifies as our bss matching bssid and essid */
 static int
 goodbss(Wifi *wifi, Wnode *wn)
@@ -429,6 +448,7 @@ wifiproc(void *arg)
 			memset(wn->rxkey, 0, sizeof(wn->rxkey));
 			memset(wn->txkey, 0, sizeof(wn->txkey));
 			wn->aid = 0;
+			wifideassoc(wifi);
 			sendauth(wifi, wn);
 			break;
 		}