[3/3] cfg80211: disallow bridging managed/adhoc interfaces

Commit Message

Johannes Berg Nov. 18, 2009, 11:56 p.m. UTC

None

Patch

--- wireless-testing.orig/include/linux/if.h	2009-11-19 00:22:18.000000000 +0100
+++ wireless-testing/include/linux/if.h	2009-11-19 00:23:17.000000000 +0100
@@ -70,6 +70,7 @@ 
 #define IFF_XMIT_DST_RELEASE 0x400	/* dev_hard_start_xmit() is allowed to
 					 * release skb->dst
 					 */
+#define IFF_DONT_BRIDGE 0x800		/* disallow bridging this ether dev */
 
 #define IF_GET_IFACE	0x0001		/* for querying only */
 #define IF_GET_PROTO	0x0002
--- wireless-testing.orig/net/bridge/br_if.c	2009-11-19 00:22:18.000000000 +0100
+++ wireless-testing/net/bridge/br_if.c	2009-11-19 00:23:17.000000000 +0100
@@ -390,6 +390,10 @@  int br_add_if(struct net_bridge *br, str
 	if (dev->br_port != NULL)
 		return -EBUSY;
 
+	/* No bridging devices that dislike that (e.g. wireless) */
+	if (dev->priv_flags & IFF_DONT_BRIDGE)
+		return -EOPNOTSUPP;
+
 	p = new_nbp(br, dev);
 	if (IS_ERR(p))
 		return PTR_ERR(p);
--- wireless-testing.orig/net/wireless/util.c	2009-11-19 00:22:18.000000000 +0100
+++ wireless-testing/net/wireless/util.c	2009-11-19 00:23:17.000000000 +0100
@@ -658,6 +658,11 @@  int cfg80211_change_iface(struct cfg8021
 	    !(rdev->wiphy.interface_modes & (1 << ntype)))
 		return -EOPNOTSUPP;
 
+	/* if it's part of a bridge, reject changing type to station/ibss */
+	if (dev->br_port && (ntype == NL80211_IFTYPE_ADHOC ||
+			     ntype == NL80211_IFTYPE_STATION))
+		return -EBUSY;
+
 	if (ntype != otype) {
 		dev->ieee80211_ptr->use_4addr = false;
 
@@ -687,5 +692,31 @@  int cfg80211_change_iface(struct cfg8021
 	if (!err && params && params->use_4addr != -1)
 		dev->ieee80211_ptr->use_4addr = params->use_4addr;
 
+	if (!err) {
+		dev->priv_flags &= ~IFF_DONT_BRIDGE;
+		switch (ntype) {
+		case NL80211_IFTYPE_STATION:
+			if (dev->ieee80211_ptr->use_4addr)
+				break;
+			/* fall through */
+		case NL80211_IFTYPE_ADHOC:
+			dev->priv_flags |= IFF_DONT_BRIDGE;
+			break;
+		case NL80211_IFTYPE_AP:
+		case NL80211_IFTYPE_AP_VLAN:
+		case NL80211_IFTYPE_WDS:
+		case NL80211_IFTYPE_MESH_POINT:
+			/* bridging OK */
+			break;
+		case NL80211_IFTYPE_MONITOR:
+			/* monitor can't bridge anyway */
+			break;
+		case NL80211_IFTYPE_UNSPECIFIED:
+		case __NL80211_IFTYPE_AFTER_LAST:
+			/* not happening */
+			break;
+		}
+	}
+
 	return err;
 }
--- wireless-testing.orig/net/wireless/core.c	2009-11-19 00:22:18.000000000 +0100
+++ wireless-testing/net/wireless/core.c	2009-11-19 00:23:17.000000000 +0100
@@ -691,6 +691,10 @@  static int cfg80211_netdev_notifier_call
 #endif
 		if (!dev->ethtool_ops)
 			dev->ethtool_ops = &cfg80211_ethtool_ops;
+
+		if ((wdev->iftype == NL80211_IFTYPE_STATION ||
+		     wdev->iftype == NL80211_IFTYPE_ADHOC) && !wdev->use_4addr)
+			dev->priv_flags |= IFF_DONT_BRIDGE;
 		break;
 	case NETDEV_GOING_DOWN:
 		switch (wdev->iftype) {
--- wireless-testing.orig/net/wireless/nl80211.c	2009-11-19 00:23:43.000000000 +0100
+++ wireless-testing/net/wireless/nl80211.c	2009-11-19 00:26:04.000000000 +0100
@@ -969,10 +969,14 @@  static int parse_monitor_flags(struct nl
 }
 
 static int nl80211_valid_4addr(struct cfg80211_registered_device *rdev,
-			       u8 use_4addr, enum nl80211_iftype iftype)
+			       struct net_device *netdev, u8 use_4addr,
+			       enum nl80211_iftype iftype)
 {
-	if (!use_4addr)
+	if (!use_4addr) {
+		if (netdev && netdev->br_port)
+			return -EBUSY;
 		return 0;
+	}
 
 	switch (iftype) {
 	case NL80211_IFTYPE_AP_VLAN:
@@ -1033,7 +1037,7 @@  static int nl80211_set_interface(struct 
 	if (info->attrs[NL80211_ATTR_4ADDR]) {
 		params.use_4addr = !!nla_get_u8(info->attrs[NL80211_ATTR_4ADDR]);
 		change = true;
-		err = nl80211_valid_4addr(rdev, params.use_4addr, ntype);
+		err = nl80211_valid_4addr(rdev, dev, params.use_4addr, ntype);
 		if (err)
 			goto unlock;
 	} else {
@@ -1111,7 +1115,7 @@  static int nl80211_new_interface(struct 
 
 	if (info->attrs[NL80211_ATTR_4ADDR]) {
 		params.use_4addr = !!nla_get_u8(info->attrs[NL80211_ATTR_4ADDR]);
-		err = nl80211_valid_4addr(rdev, params.use_4addr, type);
+		err = nl80211_valid_4addr(rdev, NULL, params.use_4addr, type);
 		if (err)
 			goto unlock;
 	}