Skip to content

Commit

Permalink
6lowpan: Use netdev addr_len to determine lladdr len
Browse files Browse the repository at this point in the history 
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 <[email protected]>
Reviewed-by: Stefan Schmidt <[email protected]>
Signed-off-by: Marcel Holtmann <[email protected]>
  • Loading branch information
@Vudentz @holtmann
Vudentz authored and holtmann committed Apr 12, 2017
1 parent 8a7a4b4 commit fa09ae6
Show file tree
Hide file tree
Showing 3 changed files with 63 additions and 47 deletions.
19 changes: 19 additions & 0 deletions include/net/6lowpan.h
View file
Original file line number Diff line number Diff line change
Expand Up @@ -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,
Expand Down
49 changes: 38 additions & 11 deletions net/6lowpan/iphc.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -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).
*
Expand Down Expand Up @@ -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;
Expand Down Expand Up @@ -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);
Expand Down Expand Up @@ -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,
Expand All @@ -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;
}
Expand Down Expand Up @@ -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;
}

Expand Down
42 changes: 6 additions & 36 deletions net/bluetooth/6lowpan.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -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;
};

Expand All @@ -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)
{
Expand Down Expand Up @@ -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);

Expand All @@ -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,
Expand Down Expand Up @@ -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;
Expand Down Expand Up @@ -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;
Expand Down Expand Up @@ -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.
Expand Down

0 comments on commit fa09ae6

Please sign in to comment.