[PATCH v6 0/6] Bluetooth: 6LoWPAN: Fix lladdr length

[PATCH v6 0/6] Bluetooth: 6LoWPAN: Fix lladdr length

[Luiz Augusto von Dentz]

From: Luiz Augusto von Dentz <luiz.von.dentz-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>

These patches fixes lladdr length to be 6 bytes long and not 8 which cause
neighbor advertisement to be sent with wrong lladdr including FF:FE filler
bytes for eui64.

Note: This does not fix some of the existing crashes which I hope to address
in a different set.

v2: Make all code paths that generate a link-local from lladdr use the same
code.
v3: Use lowpan_iphc_uncompress_eui48_lladdr to generate the remote ip address.
v4: Handle comments from Stefan Schmidt.
v5: Add patch to fix IID format for Bluetooth
v6: Fix addrconf_ifid_eui48 to follow IID format for Bluetooth

Alexander Aring (2):
  6lowpan: iphc: override l2 packet information
  ipv6: addrconf: fix 48 bit 6lowpan autoconfiguration

Luiz Augusto von Dentz (2):
  6lowpan: Use netdev addr_len to determine lladdr len
  6lowpan: Fix IID format for Bluetooth

Patrik Flykt (2):
  bluetooth: Set 6 byte device addresses
  6lowpan: Set MAC address length according to LOWPAN_LLTYPE

 include/net/6lowpan.h   |  15 ++++++
 include/net/addrconf.h  |   7 ++-
 net/6lowpan/core.c      |  11 +++-
 net/6lowpan/iphc.c      |  57 +++++++++++++++++----
 net/bluetooth/6lowpan.c | 130 ++++++++----------------------------------------
 net/ipv6/addrconf.c     |  17 +++++--
 6 files changed, 110 insertions(+), 127 deletions(-)

-- 
2.9.3

[PATCH v6 1/6] bluetooth: Set 6 byte device addresses

[Luiz Augusto von Dentz]

From: Patrik Flykt <patrik.flykt@linux.intel.com>

Set BTLE MAC addresses that are 6 bytes long and not 8 bytes
that are used in other places with 6lowpan.

Signed-off-by: Patrik Flykt <patrik.flykt@linux.intel.com>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Reviewed-by: Stefan Schmidt <stefan@osg.samsung.com>
---
 net/bluetooth/6lowpan.c | 19 ++++++++-----------
 1 file changed, 8 insertions(+), 11 deletions(-)

diff --git a/net/bluetooth/6lowpan.c b/net/bluetooth/6lowpan.c
index 1904a93..1456b01 100644
--- a/net/bluetooth/6lowpan.c
+++ b/net/bluetooth/6lowpan.c
@@ -80,6 +80,8 @@ struct lowpan_btle_dev {
 	struct delayed_work notify_peers;
 };
 
+static void set_addr(u8 *eui, u8 *addr, u8 addr_type);
+
 static inline struct lowpan_btle_dev *
 lowpan_btle_dev(const struct net_device *netdev)
 {
@@ -272,9 +274,10 @@ static int give_skb_to_upper(struct sk_buff *skb, struct net_device *dev)
 static int iphc_decompress(struct sk_buff *skb, struct net_device *netdev,
 			   struct l2cap_chan *chan)
 {
-	const u8 *saddr, *daddr;
+	const u8 *saddr;
 	struct lowpan_btle_dev *dev;
 	struct lowpan_peer *peer;
+	unsigned char eui64_daddr[EUI64_ADDR_LEN];
 
 	dev = lowpan_btle_dev(netdev);
 
@@ -285,9 +288,9 @@ static int iphc_decompress(struct sk_buff *skb, struct net_device *netdev,
 		return -EINVAL;
 
 	saddr = peer->eui64_addr;
-	daddr = dev->netdev->dev_addr;
+	set_addr(&eui64_daddr[0], chan->src.b, chan->src_type);
 
-	return lowpan_header_decompress(skb, netdev, daddr, saddr);
+	return lowpan_header_decompress(skb, netdev, &eui64_daddr, saddr);
 }
 
 static int recv_pkt(struct sk_buff *skb, struct net_device *dev,
@@ -681,13 +684,6 @@ static void set_addr(u8 *eui, u8 *addr, u8 addr_type)
 	BT_DBG("type %d addr %*phC", addr_type, 8, eui);
 }
 
-static void set_dev_addr(struct net_device *netdev, bdaddr_t *addr,
-		         u8 addr_type)
-{
-	netdev->addr_assign_type = NET_ADDR_PERM;
-	set_addr(netdev->dev_addr, addr->b, addr_type);
-}
-
 static void ifup(struct net_device *netdev)
 {
 	int err;
@@ -803,7 +799,8 @@ static int setup_netdev(struct l2cap_chan *chan, struct lowpan_btle_dev **dev)
 	if (!netdev)
 		return -ENOMEM;
 
-	set_dev_addr(netdev, &chan->src, chan->src_type);
+	netdev->addr_assign_type = NET_ADDR_PERM;
+	baswap((void *)netdev->dev_addr, &chan->src);
 
 	netdev->netdev_ops = &netdev_ops;
 	SET_NETDEV_DEV(netdev, &chan->conn->hcon->hdev->dev);
-- 
2.9.3

[PATCH v6 2/6] 6lowpan: Set MAC address length according to LOWPAN_LLTYPE

[Luiz Augusto von Dentz]

From: Patrik Flykt <patrik.flykt-VuQAYsv1563Yd54FQh9/CA@public.gmane.org>

Set MAC address length according to the 6LoWPAN link layer in use.
Bluetooth Low Energy uses 48 bit addressing while IEEE802.15.4 uses
64 bits.

Signed-off-by: Patrik Flykt <patrik.flykt-VuQAYsv1563Yd54FQh9/CA@public.gmane.org>
Reviewed-by: Stefan Schmidt <stefan-JPH+aEBZ4P+UEJcrhfAQsw@public.gmane.org>
---
 net/6lowpan/core.c | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/net/6lowpan/core.c b/net/6lowpan/core.c
index 5945f7e..5f9909a 100644
--- a/net/6lowpan/core.c
+++ b/net/6lowpan/core.c
@@ -23,7 +23,16 @@ int lowpan_register_netdevice(struct net_device *dev,
 {
 	int i, ret;
 
-	dev->addr_len = EUI64_ADDR_LEN;
+	switch (lltype) {
+	case LOWPAN_LLTYPE_IEEE802154:
+		dev->addr_len = EUI64_ADDR_LEN;
+		break;
+
+	case LOWPAN_LLTYPE_BTLE:
+		dev->addr_len = ETH_ALEN;
+		break;
+	}
+
 	dev->type = ARPHRD_6LOWPAN;
 	dev->mtu = IPV6_MIN_MTU;
 	dev->priv_flags |= IFF_NO_QUEUE;
-- 
2.9.3

[PATCH v6 3/6] 6lowpan: iphc: override l2 packet information

[Luiz Augusto von Dentz]

From: Alexander Aring <aar@pengutronix.de>

The skb->pkt_type need to be set by L2, but on 6LoWPAN there exists L2
e.g. BTLE which doesn't has multicast addressing. If it's a multicast or
not is detected by IPHC headers multicast bit. The IPv6 layer will
evaluate this pkt_type, so we force set this type while uncompressing.
Should be okay for 802.15.4 as well.

Signed-off-by: Alexander Aring <aar@pengutronix.de>
Reviewed-by: Stefan Schmidt <stefan@osg.samsung.com>
---
 net/6lowpan/iphc.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/net/6lowpan/iphc.c b/net/6lowpan/iphc.c
index 79f1fa2..fb5f6fa 100644
--- a/net/6lowpan/iphc.c
+++ b/net/6lowpan/iphc.c
@@ -666,6 +666,8 @@ int lowpan_header_decompress(struct sk_buff *skb, const struct net_device *dev,
 
 	switch (iphc1 & (LOWPAN_IPHC_M | LOWPAN_IPHC_DAC)) {
 	case LOWPAN_IPHC_M | LOWPAN_IPHC_DAC:
+		skb->pkt_type = PACKET_BROADCAST;
+
 		spin_lock_bh(&lowpan_dev(dev)->ctx.lock);
 		ci = lowpan_iphc_ctx_get_by_id(dev, LOWPAN_IPHC_CID_DCI(cid));
 		if (!ci) {
@@ -681,11 +683,15 @@ int lowpan_header_decompress(struct sk_buff *skb, const struct net_device *dev,
 		spin_unlock_bh(&lowpan_dev(dev)->ctx.lock);
 		break;
 	case LOWPAN_IPHC_M:
+		skb->pkt_type = PACKET_BROADCAST;
+
 		/* multicast */
 		err = lowpan_uncompress_multicast_daddr(skb, &hdr.daddr,
 							iphc1 & LOWPAN_IPHC_DAM_MASK);
 		break;
 	case LOWPAN_IPHC_DAC:
+		skb->pkt_type = PACKET_HOST;
+
 		spin_lock_bh(&lowpan_dev(dev)->ctx.lock);
 		ci = lowpan_iphc_ctx_get_by_id(dev, LOWPAN_IPHC_CID_DCI(cid));
 		if (!ci) {
@@ -701,6 +707,8 @@ int lowpan_header_decompress(struct sk_buff *skb, const struct net_device *dev,
 		spin_unlock_bh(&lowpan_dev(dev)->ctx.lock);
 		break;
 	default:
+		skb->pkt_type = PACKET_HOST;
+
 		err = lowpan_iphc_uncompress_addr(skb, dev, &hdr.daddr,
 						  iphc1 & LOWPAN_IPHC_DAM_MASK,
 						  daddr);
-- 
2.9.3

[PATCH v6 4/6] ipv6: addrconf: fix 48 bit 6lowpan autoconfiguration

[Luiz Augusto von Dentz]

From: Alexander Aring <aar@pengutronix.de>

This patch adds support for 48 bit 6LoWPAN address length
autoconfiguration which is the case for BTLE 6LoWPAN.

Signed-off-by: Alexander Aring <aar@pengutronix.de>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Reviewed-by: Stefan Schmidt <stefan@osg.samsung.com>
Acked-by: David S. Miller <davem@davemloft.net>
---
 net/ipv6/addrconf.c | 17 ++++++++++++-----
 1 file changed, 12 insertions(+), 5 deletions(-)

diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c
index 3a2025f..7756640 100644
--- a/net/ipv6/addrconf.c
+++ b/net/ipv6/addrconf.c
@@ -2052,12 +2052,19 @@ static void addrconf_leave_anycast(struct inet6_ifaddr *ifp)
 	__ipv6_dev_ac_dec(ifp->idev, &addr);
 }
 
-static int addrconf_ifid_eui64(u8 *eui, struct net_device *dev)
+static int addrconf_ifid_6lowpan(u8 *eui, struct net_device *dev)
 {
-	if (dev->addr_len != EUI64_ADDR_LEN)
+	switch (dev->addr_len) {
+	case ETH_ALEN:
+		return addrconf_ifid_eui48(eui, dev);
+	case EUI64_ADDR_LEN:
+		memcpy(eui, dev->dev_addr, EUI64_ADDR_LEN);
+		eui[0] ^= 2;
+		break;
+	default:
 		return -1;
-	memcpy(eui, dev->dev_addr, EUI64_ADDR_LEN);
-	eui[0] ^= 2;
+	}
+
 	return 0;
 }
 
@@ -2149,7 +2156,7 @@ static int ipv6_generate_eui64(u8 *eui, struct net_device *dev)
 	case ARPHRD_TUNNEL:
 		return addrconf_ifid_gre(eui, dev);
 	case ARPHRD_6LOWPAN:
-		return addrconf_ifid_eui64(eui, dev);
+		return addrconf_ifid_6lowpan(eui, dev);
 	case ARPHRD_IEEE1394:
 		return addrconf_ifid_ieee1394(eui, dev);
 	case ARPHRD_TUNNEL6:
-- 
2.9.3

[PATCH v6 5/6] 6lowpan: Use netdev addr_len to determine lladdr len

[Luiz Augusto von Dentz]

From: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>

This allow technologies such as Bluetooth to use its native lladdr which
is eui48 instead of eui64 which was expected by functions like
lowpan_header_decompress and lowpan_header_compress.

Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Reviewed-by: Stefan Schmidt <stefan@osg.samsung.com>
---
 include/net/6lowpan.h   | 19 +++++++++++++++++++
 net/6lowpan/iphc.c      | 49 ++++++++++++++++++++++++++++++++++++++-----------
 net/bluetooth/6lowpan.c | 42 ++++++------------------------------------
 3 files changed, 63 insertions(+), 47 deletions(-)

diff --git a/include/net/6lowpan.h b/include/net/6lowpan.h
index 5ab4c99..c5792cb 100644
--- a/include/net/6lowpan.h
+++ b/include/net/6lowpan.h
@@ -198,6 +198,25 @@ static inline void lowpan_iphc_uncompress_eui64_lladdr(struct in6_addr *ipaddr,
 	ipaddr->s6_addr[8] ^= 0x02;
 }
 
+static inline void lowpan_iphc_uncompress_eui48_lladdr(struct in6_addr *ipaddr,
+						       const void *lladdr)
+{
+	/* fe:80::XXXX:XXff:feXX:XXXX
+	 *        \_________________/
+	 *              hwaddr
+	 */
+	ipaddr->s6_addr[0] = 0xFE;
+	ipaddr->s6_addr[1] = 0x80;
+	memcpy(&ipaddr->s6_addr[8], lladdr, 3);
+	ipaddr->s6_addr[11] = 0xFF;
+	ipaddr->s6_addr[12] = 0xFE;
+	memcpy(&ipaddr->s6_addr[13], lladdr + 3, 3);
+	/* second bit-flip (Universe/Local)
+	 * is done according RFC2464
+	 */
+	ipaddr->s6_addr[8] ^= 0x02;
+}
+
 #ifdef DEBUG
 /* print data in line */
 static inline void raw_dump_inline(const char *caller, char *msg,
diff --git a/net/6lowpan/iphc.c b/net/6lowpan/iphc.c
index fb5f6fa..6b1042e 100644
--- a/net/6lowpan/iphc.c
+++ b/net/6lowpan/iphc.c
@@ -278,6 +278,23 @@ lowpan_iphc_ctx_get_by_mcast_addr(const struct net_device *dev,
 	return ret;
 }
 
+static void lowpan_iphc_uncompress_lladdr(const struct net_device *dev,
+					  struct in6_addr *ipaddr,
+					  const void *lladdr)
+{
+	switch (dev->addr_len) {
+	case ETH_ALEN:
+		lowpan_iphc_uncompress_eui48_lladdr(ipaddr, lladdr);
+		break;
+	case EUI64_ADDR_LEN:
+		lowpan_iphc_uncompress_eui64_lladdr(ipaddr, lladdr);
+		break;
+	default:
+		WARN_ON_ONCE(1);
+		break;
+	}
+}
+
 /* Uncompress address function for source and
  * destination address(non-multicast).
  *
@@ -320,7 +337,7 @@ static int lowpan_iphc_uncompress_addr(struct sk_buff *skb,
 			lowpan_iphc_uncompress_802154_lladdr(ipaddr, lladdr);
 			break;
 		default:
-			lowpan_iphc_uncompress_eui64_lladdr(ipaddr, lladdr);
+			lowpan_iphc_uncompress_lladdr(dev, ipaddr, lladdr);
 			break;
 		}
 		break;
@@ -381,7 +398,7 @@ static int lowpan_iphc_uncompress_ctx_addr(struct sk_buff *skb,
 			lowpan_iphc_uncompress_802154_lladdr(ipaddr, lladdr);
 			break;
 		default:
-			lowpan_iphc_uncompress_eui64_lladdr(ipaddr, lladdr);
+			lowpan_iphc_uncompress_lladdr(dev, ipaddr, lladdr);
 			break;
 		}
 		ipv6_addr_prefix_copy(ipaddr, &ctx->pfx, ctx->plen);
@@ -810,6 +827,21 @@ lowpan_iphc_compress_ctx_802154_lladdr(const struct in6_addr *ipaddr,
 	return lladdr_compress;
 }
 
+static bool lowpan_iphc_addr_equal(const struct net_device *dev,
+				   const struct lowpan_iphc_ctx *ctx,
+				   const struct in6_addr *ipaddr,
+				   const void *lladdr)
+{
+	struct in6_addr tmp = {};
+
+	lowpan_iphc_uncompress_lladdr(dev, &tmp, lladdr);
+
+	if (ctx)
+		ipv6_addr_prefix_copy(&tmp, &ctx->pfx, ctx->plen);
+
+	return ipv6_addr_equal(&tmp, ipaddr);
+}
+
 static u8 lowpan_compress_ctx_addr(u8 **hc_ptr, const struct net_device *dev,
 				   const struct in6_addr *ipaddr,
 				   const struct lowpan_iphc_ctx *ctx,
@@ -827,13 +859,7 @@ static u8 lowpan_compress_ctx_addr(u8 **hc_ptr, const struct net_device *dev,
 		}
 		break;
 	default:
-		/* check for SAM/DAM = 11 */
-		memcpy(&tmp.s6_addr[8], lladdr, EUI64_ADDR_LEN);
-		/* second bit-flip (Universe/Local) is done according RFC2464 */
-		tmp.s6_addr[8] ^= 0x02;
-		/* context information are always used */
-		ipv6_addr_prefix_copy(&tmp, &ctx->pfx, ctx->plen);
-		if (ipv6_addr_equal(&tmp, ipaddr)) {
+		if (lowpan_iphc_addr_equal(dev, ctx, ipaddr, lladdr)) {
 			dam = LOWPAN_IPHC_DAM_11;
 			goto out;
 		}
@@ -929,11 +955,12 @@ static u8 lowpan_compress_addr_64(u8 **hc_ptr, const struct net_device *dev,
 		}
 		break;
 	default:
-		if (is_addr_mac_addr_based(ipaddr, lladdr)) {
-			dam = LOWPAN_IPHC_DAM_11; /* 0-bits */
+		if (lowpan_iphc_addr_equal(dev, NULL, ipaddr, lladdr)) {
+			dam = LOWPAN_IPHC_DAM_11;
 			pr_debug("address compression 0 bits\n");
 			goto out;
 		}
+
 		break;
 	}
 
diff --git a/net/bluetooth/6lowpan.c b/net/bluetooth/6lowpan.c
index 1456b01..0b68cfc 100644
--- a/net/bluetooth/6lowpan.c
+++ b/net/bluetooth/6lowpan.c
@@ -64,7 +64,7 @@ struct lowpan_peer {
 	struct l2cap_chan *chan;
 
 	/* peer addresses in various formats */
-	unsigned char eui64_addr[EUI64_ADDR_LEN];
+	unsigned char lladdr[ETH_ALEN];
 	struct in6_addr peer_addr;
 };
 
@@ -80,8 +80,6 @@ struct lowpan_btle_dev {
 	struct delayed_work notify_peers;
 };
 
-static void set_addr(u8 *eui, u8 *addr, u8 addr_type);
-
 static inline struct lowpan_btle_dev *
 lowpan_btle_dev(const struct net_device *netdev)
 {
@@ -277,7 +275,6 @@ static int iphc_decompress(struct sk_buff *skb, struct net_device *netdev,
 	const u8 *saddr;
 	struct lowpan_btle_dev *dev;
 	struct lowpan_peer *peer;
-	unsigned char eui64_daddr[EUI64_ADDR_LEN];
 
 	dev = lowpan_btle_dev(netdev);
 
@@ -287,10 +284,9 @@ static int iphc_decompress(struct sk_buff *skb, struct net_device *netdev,
 	if (!peer)
 		return -EINVAL;
 
-	saddr = peer->eui64_addr;
-	set_addr(&eui64_daddr[0], chan->src.b, chan->src_type);
+	saddr = peer->lladdr;
 
-	return lowpan_header_decompress(skb, netdev, &eui64_daddr, saddr);
+	return lowpan_header_decompress(skb, netdev, netdev->dev_addr, saddr);
 }
 
 static int recv_pkt(struct sk_buff *skb, struct net_device *dev,
@@ -477,7 +473,7 @@ static int setup_header(struct sk_buff *skb, struct net_device *netdev,
 			}
 		}
 
-		daddr = peer->eui64_addr;
+		daddr = peer->lladdr;
 		*peer_addr = addr;
 		*peer_addr_type = addr_type;
 		lowpan_cb(skb)->chan = peer->chan;
@@ -663,27 +659,6 @@ static struct device_type bt_type = {
 	.name	= "bluetooth",
 };
 
-static void set_addr(u8 *eui, u8 *addr, u8 addr_type)
-{
-	/* addr is the BT address in little-endian format */
-	eui[0] = addr[5];
-	eui[1] = addr[4];
-	eui[2] = addr[3];
-	eui[3] = 0xFF;
-	eui[4] = 0xFE;
-	eui[5] = addr[2];
-	eui[6] = addr[1];
-	eui[7] = addr[0];
-
-	/* Universal/local bit set, BT 6lowpan draft ch. 3.2.1 */
-	if (addr_type == BDADDR_LE_PUBLIC)
-		eui[0] &= ~0x02;
-	else
-		eui[0] |= 0x02;
-
-	BT_DBG("type %d addr %*phC", addr_type, 8, eui);
-}
-
 static void ifup(struct net_device *netdev)
 {
 	int err;
@@ -762,14 +737,9 @@ static struct l2cap_chan *add_peer_chan(struct l2cap_chan *chan,
 	peer->chan = chan;
 	memset(&peer->peer_addr, 0, sizeof(struct in6_addr));
 
-	/* RFC 2464 ch. 5 */
-	peer->peer_addr.s6_addr[0] = 0xFE;
-	peer->peer_addr.s6_addr[1] = 0x80;
-	set_addr((u8 *)&peer->peer_addr.s6_addr + 8, chan->dst.b,
-		 chan->dst_type);
+	baswap((void *)peer->lladdr, &chan->dst);
 
-	memcpy(&peer->eui64_addr, (u8 *)&peer->peer_addr.s6_addr + 8,
-	       EUI64_ADDR_LEN);
+	lowpan_iphc_uncompress_eui48_lladdr(&peer->peer_addr, peer->lladdr);
 
 	/* IPv6 address needs to have the U/L bit set properly so toggle
 	 * it back here.
-- 
2.9.3

[PATCH v6 6/6] 6lowpan: Fix IID format for Bluetooth

[Luiz Augusto von Dentz]

From: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>

According to RFC 7668 U/L bit shall not be used:

https://wiki.tools.ietf.org/html/rfc7668#section-3.2.2 [Page 10]:

   In the figure, letter 'b' represents a bit from the
   Bluetooth device address, copied as is without any changes on any
   bit.  This means that no bit in the IID indicates whether the
   underlying Bluetooth device address is public or random.

   |0              1|1              3|3              4|4              6|
   |0              5|6              1|2              7|8              3|
   +----------------+----------------+----------------+----------------+
   |bbbbbbbbbbbbbbbb|bbbbbbbb11111111|11111110bbbbbbbb|bbbbbbbbbbbbbbbb|
   +----------------+----------------+----------------+----------------+

Because of this the code cannot figure out the address type from the IP
address anymore thus it makes no sense to use peer_lookup_ba as it needs
the peer address type.

Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Reviewed-by: Stefan Schmidt <stefan@osg.samsung.com>
Acked-by: Jukka Rissanen <jukka.rissanen@linux.intel.com>
---
 include/net/6lowpan.h   |  4 ---
 include/net/addrconf.h  |  7 ++++-
 net/bluetooth/6lowpan.c | 79 ++++++++-----------------------------------------
 3 files changed, 18 insertions(+), 72 deletions(-)

diff --git a/include/net/6lowpan.h b/include/net/6lowpan.h
index c5792cb..a713780 100644
--- a/include/net/6lowpan.h
+++ b/include/net/6lowpan.h
@@ -211,10 +211,6 @@ static inline void lowpan_iphc_uncompress_eui48_lladdr(struct in6_addr *ipaddr,
 	ipaddr->s6_addr[11] = 0xFF;
 	ipaddr->s6_addr[12] = 0xFE;
 	memcpy(&ipaddr->s6_addr[13], lladdr + 3, 3);
-	/* second bit-flip (Universe/Local)
-	 * is done according RFC2464
-	 */
-	ipaddr->s6_addr[8] ^= 0x02;
 }
 
 #ifdef DEBUG
diff --git a/include/net/addrconf.h b/include/net/addrconf.h
index 17c6fd8..3931fd2 100644
--- a/include/net/addrconf.h
+++ b/include/net/addrconf.h
@@ -129,7 +129,12 @@ static inline int addrconf_ifid_eui48(u8 *eui, struct net_device *dev)
 	} else {
 		eui[3] = 0xFF;
 		eui[4] = 0xFE;
-		eui[0] ^= 2;
+
+		/*
+		 * According to RFC 7668 U/L bit shall not be toggled.
+		 */
+		if (dev->type != ARPHRD_6LOWPAN)
+			eui[0] ^= 2;
 	}
 	return 0;
 }
diff --git a/net/bluetooth/6lowpan.c b/net/bluetooth/6lowpan.c
index 0b68cfc..ec89c55 100644
--- a/net/bluetooth/6lowpan.c
+++ b/net/bluetooth/6lowpan.c
@@ -398,37 +398,6 @@ static int chan_recv_cb(struct l2cap_chan *chan, struct sk_buff *skb)
 	return err;
 }
 
-static u8 get_addr_type_from_eui64(u8 byte)
-{
-	/* Is universal(0) or local(1) bit */
-	return ((byte & 0x02) ? BDADDR_LE_RANDOM : BDADDR_LE_PUBLIC);
-}
-
-static void copy_to_bdaddr(struct in6_addr *ip6_daddr, bdaddr_t *addr)
-{
-	u8 *eui64 = ip6_daddr->s6_addr + 8;
-
-	addr->b[0] = eui64[7];
-	addr->b[1] = eui64[6];
-	addr->b[2] = eui64[5];
-	addr->b[3] = eui64[2];
-	addr->b[4] = eui64[1];
-	addr->b[5] = eui64[0];
-}
-
-static void convert_dest_bdaddr(struct in6_addr *ip6_daddr,
-				bdaddr_t *addr, u8 *addr_type)
-{
-	copy_to_bdaddr(ip6_daddr, addr);
-
-	/* We need to toggle the U/L bit that we got from IPv6 address
-	 * so that we get the proper address and type of the BD address.
-	 */
-	addr->b[5] ^= 0x02;
-
-	*addr_type = get_addr_type_from_eui64(addr->b[5]);
-}
-
 static int setup_header(struct sk_buff *skb, struct net_device *netdev,
 			bdaddr_t *peer_addr, u8 *peer_addr_type)
 {
@@ -436,8 +405,7 @@ static int setup_header(struct sk_buff *skb, struct net_device *netdev,
 	struct ipv6hdr *hdr;
 	struct lowpan_btle_dev *dev;
 	struct lowpan_peer *peer;
-	bdaddr_t addr, *any = BDADDR_ANY;
-	u8 *daddr = any->b;
+	u8 *daddr;
 	int err, status = 0;
 
 	hdr = ipv6_hdr(skb);
@@ -448,34 +416,24 @@ static int setup_header(struct sk_buff *skb, struct net_device *netdev,
 
 	if (ipv6_addr_is_multicast(&ipv6_daddr)) {
 		lowpan_cb(skb)->chan = NULL;
+		daddr = NULL;
 	} else {
-		u8 addr_type;
+		BT_DBG("dest IP %pI6c", &ipv6_daddr);
 
-		/* Get destination BT device from skb.
-		 * If there is no such peer then discard the packet.
+		/* The packet might be sent to 6lowpan interface
+		 * because of routing (either via default route
+		 * or user set route) so get peer according to
+		 * the destination address.
 		 */
-		convert_dest_bdaddr(&ipv6_daddr, &addr, &addr_type);
-
-		BT_DBG("dest addr %pMR type %d IP %pI6c", &addr,
-		       addr_type, &ipv6_daddr);
-
-		peer = peer_lookup_ba(dev, &addr, addr_type);
+		peer = peer_lookup_dst(dev, &ipv6_daddr, skb);
 		if (!peer) {
-			/* The packet might be sent to 6lowpan interface
-			 * because of routing (either via default route
-			 * or user set route) so get peer according to
-			 * the destination address.
-			 */
-			peer = peer_lookup_dst(dev, &ipv6_daddr, skb);
-			if (!peer) {
-				BT_DBG("no such peer %pMR found", &addr);
-				return -ENOENT;
-			}
+			BT_DBG("no such peer");
+			return -ENOENT;
 		}
 
 		daddr = peer->lladdr;
-		*peer_addr = addr;
-		*peer_addr_type = addr_type;
+		peer_addr = &peer->chan->dst;
+		*peer_addr_type = peer->chan->dst_type;
 		lowpan_cb(skb)->chan = peer->chan;
 
 		status = 1;
@@ -717,14 +675,6 @@ static struct l2cap_chan *chan_create(void)
 	return chan;
 }
 
-static void set_ip_addr_bits(u8 addr_type, u8 *addr)
-{
-	if (addr_type == BDADDR_LE_PUBLIC)
-		*addr |= 0x02;
-	else
-		*addr &= ~0x02;
-}
-
 static struct l2cap_chan *add_peer_chan(struct l2cap_chan *chan,
 					struct lowpan_btle_dev *dev)
 {
@@ -741,11 +691,6 @@ static struct l2cap_chan *add_peer_chan(struct l2cap_chan *chan,
 
 	lowpan_iphc_uncompress_eui48_lladdr(&peer->peer_addr, peer->lladdr);
 
-	/* IPv6 address needs to have the U/L bit set properly so toggle
-	 * it back here.
-	 */
-	set_ip_addr_bits(chan->dst_type, (u8 *)&peer->peer_addr.s6_addr + 8);
-
 	spin_lock(&devices_lock);
 	INIT_LIST_HEAD(&peer->list);
 	peer_add(dev, peer);
-- 
2.9.3

Re: [PATCH v6 6/6] 6lowpan: Fix IID format for Bluetooth

[Alexander Aring]

Hi,

sorry, I decided now to take a look into the patch... Currently I have
no time to do anything... normally. That's why I simple said "everything
okay" in irc.

On 03/02/2017 02:23 PM, Luiz Augusto von Dentz wrote:
> From: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
> 
> According to RFC 7668 U/L bit shall not be used:
> 
> https://wiki.tools.ietf.org/html/rfc7668#section-3.2.2 [Page 10]:
> 
>    In the figure, letter 'b' represents a bit from the
>    Bluetooth device address, copied as is without any changes on any
>    bit.  This means that no bit in the IID indicates whether the
>    underlying Bluetooth device address is public or random.
> 
>    |0              1|1              3|3              4|4              6|
>    |0              5|6              1|2              7|8              3|
>    +----------------+----------------+----------------+----------------+
>    |bbbbbbbbbbbbbbbb|bbbbbbbb11111111|11111110bbbbbbbb|bbbbbbbbbbbbbbbb|
>    +----------------+----------------+----------------+----------------+
> 
> Because of this the code cannot figure out the address type from the IP
> address anymore thus it makes no sense to use peer_lookup_ba as it needs
> the peer address type.
> 
> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
> Reviewed-by: Stefan Schmidt <stefan@osg.samsung.com>
> Acked-by: Jukka Rissanen <jukka.rissanen@linux.intel.com>
> ---
>  include/net/6lowpan.h   |  4 ---
>  include/net/addrconf.h  |  7 ++++-
>  net/bluetooth/6lowpan.c | 79 ++++++++-----------------------------------------
>  3 files changed, 18 insertions(+), 72 deletions(-)
> 
> diff --git a/include/net/6lowpan.h b/include/net/6lowpan.h
> index c5792cb..a713780 100644
> --- a/include/net/6lowpan.h
> +++ b/include/net/6lowpan.h
> @@ -211,10 +211,6 @@ static inline void lowpan_iphc_uncompress_eui48_lladdr(struct in6_addr *ipaddr,
>  	ipaddr->s6_addr[11] = 0xFF;
>  	ipaddr->s6_addr[12] = 0xFE;
>  	memcpy(&ipaddr->s6_addr[13], lladdr + 3, 3);
> -	/* second bit-flip (Universe/Local)
> -	 * is done according RFC2464
> -	 */
> -	ipaddr->s6_addr[8] ^= 0x02;
>  }
>  
>  #ifdef DEBUG
> diff --git a/include/net/addrconf.h b/include/net/addrconf.h
> index 17c6fd8..3931fd2 100644
> --- a/include/net/addrconf.h
> +++ b/include/net/addrconf.h
> @@ -129,7 +129,12 @@ static inline int addrconf_ifid_eui48(u8 *eui, struct net_device *dev)
>  	} else {
>  		eui[3] = 0xFF;
>  		eui[4] = 0xFE;
> -		eui[0] ^= 2;
> +
> +		/*
> +		 * According to RFC 7668 U/L bit shall not be toggled.
> +		 */
> +		if (dev->type != ARPHRD_6LOWPAN)
> +			eui[0] ^= 2;
>  	}
>  	return 0;
>  }

I don't know why you make this in such function which is called by a lot
of others dev->types which are not ARPHRD_6LOWPAN.

What addrconf does now is a switch case over dev->type and then calling
addrconf_ifid_eui48 for some cases and recheck again dev->type for a
special case of ARPHRD_6LOWPAN.

ARPHRD_6LOWPAN is also somehow wrong because you need check on ARPHRD_6LOWPAN and
LLTYPE_BTLE. As I mentioned the IPv6-over-foo adaptation describes how
to generate IID and not the dev->addr_len.

---

Second thing is we bitflip u/l and then we bitflip again because we
don't want it and do it again...

---

Anyway, I see it will working for you... but it's very confusing for me.
Don't use addrconf_ifid_eui48 here, grab 2-3 code lines from which does:

1. copy first mac addr bytes
2. set FF FE
3. copy last mac addr bytes

and this according LLTYPE_BTLE and not dev->addr_len....

---

For me it's not acceptable because you doing dev->type handling which is
already evaluated before and other subsystems will do such check as
well. We can avoid this check on others subsystems. If your IID is
different generated than a normal EUI48, then simple don't use
addrconf_ifid_eui48.

---

We already talked about to place the 8 IID bytes into 6lowpan netdev private
space. If we do that later, we need to touch addrconf_ifid_eui48
again..

- Alex