From: damien <damien@openbsd.org>
Date: Tue, 12 Aug 2008 17:53:13 +0000 (+0000)
Subject: Change the way we process EAPOL-Key frames.
X-Git-Url: http://artulab.com/gitweb/?a=commitdiff_plain;h=5027974404f02fbfad7ba28a15a517bceb26ee9c;p=openbsd

Change the way we process EAPOL-Key frames.
Free the mbuf in the ieee80211_eapol_key_input() function.
Do not assume the frame is contiguous, call m_pullup2() if it is not.
We need the frame to be contiguous to process KDEs efficiently in
EAPOL-Key frames (just like we process IEs in management frames).
However, there are drivers like upgt(4) that use m_devget() in the
RX path.  m_devget() can return fragmented mbuf chains.
Notice that we should do the same m_pullup2() for management frames.
This will be done later.
Remove the ic_recv_eapol callback.
---

diff --git a/sys/net80211/ieee80211_input.c b/sys/net80211/ieee80211_input.c
index 255f7b2352d..e643380dd14 100644
--- a/sys/net80211/ieee80211_input.c
+++ b/sys/net80211/ieee80211_input.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: ieee80211_input.c,v 1.89 2008/08/02 08:35:48 damien Exp $	*/
+/*	$OpenBSD: ieee80211_input.c,v 1.90 2008/08/12 17:53:13 damien Exp $	*/
 
 /*-
  * Copyright (c) 2001 Atsushi Onoe
@@ -426,10 +426,9 @@ ieee80211_input(struct ifnet *ifp, struct mbuf *m, struct ieee80211_node *ni,
 				bpf_mtap(ifp->if_bpf, m, BPF_DIRECTION_IN);
 #endif
 			if ((ic->ic_flags & IEEE80211_F_RSNON) &&
-			    eh->ether_type == htons(ETHERTYPE_PAE)) {
-				(*ic->ic_recv_eapol)(ic, m, ni);
-				m_freem(m);
-			} else
+			    eh->ether_type == htons(ETHERTYPE_PAE))
+				ieee80211_eapol_key_input(ic, m, ni);
+			else
 				ether_input_mbuf(ifp, m);
 		}
 		return;
diff --git a/sys/net80211/ieee80211_pae_input.c b/sys/net80211/ieee80211_pae_input.c
index 606a088c415..ca08d4e8ad3 100644
--- a/sys/net80211/ieee80211_pae_input.c
+++ b/sys/net80211/ieee80211_pae_input.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: ieee80211_pae_input.c,v 1.7 2008/08/12 16:14:05 damien Exp $	*/
+/*	$OpenBSD: ieee80211_pae_input.c,v 1.8 2008/08/12 17:53:13 damien Exp $	*/
 
 /*-
  * Copyright (c) 2007,2008 Damien Bergamini <damien.bergamini@free.fr>
@@ -66,55 +66,72 @@ void	ieee80211_recv_eapol_key_req(struct ieee80211com *,
  * EAPOL-Key frames with an IEEE 802.11 or WPA descriptor type.
  */
 void
-ieee80211_recv_eapol(struct ieee80211com *ic, struct mbuf *m0,
+ieee80211_eapol_key_input(struct ieee80211com *ic, struct mbuf *m0,
     struct ieee80211_node *ni)
 {
 	struct ifnet *ifp = &ic->ic_if;
 	struct ether_header *eh;
 	struct ieee80211_eapol_key *key;
 	u_int16_t info, desc;
+	int totlen;
 
 	ifp->if_ibytes += m0->m_pkthdr.len;
 
-	if (m0->m_len < sizeof(*eh) + sizeof(*key))
-		return;
 	eh = mtod(m0, struct ether_header *);
 	if (IEEE80211_IS_MULTICAST(eh->ether_dhost)) {
 		ifp->if_imcasts++;
-		return;
+		goto done;
 	}
 	m_adj(m0, sizeof(*eh));
+
+	if (m0->m_pkthdr.len < sizeof(*key))
+		goto done;
+	if (m0->m_len < sizeof(*key) &&
+	    (m0 = m_pullup(m0, sizeof(*key))) == NULL) {
+		ic->ic_stats.is_rx_nombuf++;
+		goto done;
+	}
+
+	ic->ic_stats.is_rx_eapol_key++;
 	key = mtod(m0, struct ieee80211_eapol_key *);
 
 	if (key->type != EAPOL_KEY)
-		return;
+		goto done;
 	ic->ic_stats.is_rx_eapol_key++;
 
 	if ((ni->ni_rsnprotos == IEEE80211_PROTO_RSN &&
 	     key->desc != EAPOL_KEY_DESC_IEEE80211) ||
 	    (ni->ni_rsnprotos == IEEE80211_PROTO_WPA &&
 	     key->desc != EAPOL_KEY_DESC_WPA))
-		return;
+		goto done;
 
 	/* check packet body length */
 	if (m0->m_len < 4 + BE_READ_2(key->len))
-		return;
+		goto done;
 
 	/* check key data length */
-	if (m0->m_len < sizeof(*key) + BE_READ_2(key->paylen))
-		return;
+	totlen = sizeof(*key) + BE_READ_2(key->paylen);
+	if (m0->m_pkthdr.len < totlen || totlen > MCLBYTES)
+		goto done;
 
 	info = BE_READ_2(key->info);
 
 	/* discard EAPOL-Key frames with an unknown descriptor version */
 	desc = info & EAPOL_KEY_VERSION_MASK;
 	if (desc != EAPOL_KEY_DESC_V1 && desc != EAPOL_KEY_DESC_V2)
-		return;
+		goto done;
 
 	if ((ni->ni_rsncipher == IEEE80211_CIPHER_CCMP ||
 	     ni->ni_rsngroupcipher == IEEE80211_CIPHER_CCMP) &&
 	    desc != EAPOL_KEY_DESC_V2)
-		return;
+		goto done;
+
+	/* make sure the key data field is contiguous */
+	if (m0->m_len < totlen && (m0 = m_pullup2(m0, totlen)) == NULL) {
+		ic->ic_stats.is_rx_nombuf++;
+		goto done;
+	}
+	key = mtod(m0, struct ieee80211_eapol_key *);
 
 	/* determine message type (see 8.5.3.7) */
 	if (info & EAPOL_KEY_REQUEST) {
@@ -133,7 +150,7 @@ ieee80211_recv_eapol(struct ieee80211com *ic, struct mbuf *m0,
 	} else {
 		/* Group Key Handshake */
 		if (!(info & EAPOL_KEY_KEYMIC))
-			return;
+			goto done;
 		if (info & EAPOL_KEY_KEYACK) {
 			if (key->desc == EAPOL_KEY_DESC_WPA)
 				ieee80211_recv_wpa_group_msg1(ic, key, ni);
@@ -142,6 +159,9 @@ ieee80211_recv_eapol(struct ieee80211com *ic, struct mbuf *m0,
 		} else
 			ieee80211_recv_group_msg2(ic, key, ni);
 	}
+ done:
+	if (m0 != NULL)
+		m_freem(m0);
 }
 
 /*
diff --git a/sys/net80211/ieee80211_proto.c b/sys/net80211/ieee80211_proto.c
index 5b8e8019b40..cef25e1495d 100644
--- a/sys/net80211/ieee80211_proto.c
+++ b/sys/net80211/ieee80211_proto.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: ieee80211_proto.c,v 1.29 2008/08/12 16:14:05 damien Exp $	*/
+/*	$OpenBSD: ieee80211_proto.c,v 1.30 2008/08/12 17:53:13 damien Exp $	*/
 /*	$NetBSD: ieee80211_proto.c,v 1.8 2004/04/30 23:58:20 dyoung Exp $	*/
 
 /*-
@@ -114,9 +114,6 @@ ieee80211_proto_attach(struct ifnet *ifp)
 	/* initialize management frame handlers */
 	ic->ic_recv_mgmt = ieee80211_recv_mgmt;
 	ic->ic_send_mgmt = ieee80211_send_mgmt;
-
-	/* initialize EAPOL frame handler */
-	ic->ic_recv_eapol = ieee80211_recv_eapol;
 }
 
 void
diff --git a/sys/net80211/ieee80211_proto.h b/sys/net80211/ieee80211_proto.h
index 1a5698a612e..51863c212cb 100644
--- a/sys/net80211/ieee80211_proto.h
+++ b/sys/net80211/ieee80211_proto.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: ieee80211_proto.h,v 1.31 2008/07/21 19:05:21 damien Exp $	*/
+/*	$OpenBSD: ieee80211_proto.h,v 1.32 2008/08/12 17:53:13 damien Exp $	*/
 /*	$NetBSD: ieee80211_proto.h,v 1.3 2003/10/13 04:23:56 dyoung Exp $	*/
 
 /*-
@@ -68,7 +68,7 @@ extern	void ieee80211_recv_mgmt(struct ieee80211com *, struct mbuf *,
 		struct ieee80211_node *, struct ieee80211_rxinfo *, int);
 extern	int ieee80211_send_mgmt(struct ieee80211com *, struct ieee80211_node *,
 		int, int);
-extern	void ieee80211_recv_eapol(struct ieee80211com *, struct mbuf *,
+extern	void ieee80211_eapol_key_input(struct ieee80211com *, struct mbuf *,
 		struct ieee80211_node *);
 extern	struct mbuf *ieee80211_encap(struct ifnet *, struct mbuf *,
 		struct ieee80211_node **);
diff --git a/sys/net80211/ieee80211_var.h b/sys/net80211/ieee80211_var.h
index b1bb482929b..c50d8c6257d 100644
--- a/sys/net80211/ieee80211_var.h
+++ b/sys/net80211/ieee80211_var.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: ieee80211_var.h,v 1.42 2008/07/28 19:42:13 damien Exp $	*/
+/*	$OpenBSD: ieee80211_var.h,v 1.43 2008/08/12 17:53:13 damien Exp $	*/
 /*	$NetBSD: ieee80211_var.h,v 1.7 2004/05/06 03:07:10 dyoung Exp $	*/
 
 /*-
@@ -178,8 +178,6 @@ struct ieee80211com {
 				    struct ieee80211_rxinfo *, int);
 	int			(*ic_send_mgmt)(struct ieee80211com *,
 				    struct ieee80211_node *, int, int);
-	void			(*ic_recv_eapol)(struct ieee80211com *,
-				    struct mbuf *, struct ieee80211_node *);
 	int			(*ic_newstate)(struct ieee80211com *,
 				    enum ieee80211_state, int);
 	void			(*ic_newassoc)(struct ieee80211com *,