Hi,
On 02/09/2017 03:55 PM, Luiz Augusto von Dentz wrote:
> From: Luiz Augusto von Dentz <luiz.von.dentz@xxxxxxxxx>
>
> 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@xxxxxxxxx>
> ---
> net/6lowpan/iphc.c | 17 +++++++++++++++--
> net/bluetooth/6lowpan.c | 43 ++++++++++---------------------------------
> 2 files changed, 25 insertions(+), 35 deletions(-)
>
> diff --git a/net/6lowpan/iphc.c b/net/6lowpan/iphc.c
> index fb5f6fa..ee88feb 100644
> --- a/net/6lowpan/iphc.c
> +++ b/net/6lowpan/iphc.c
> @@ -827,8 +827,21 @@ 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);
> + switch (dev->addr_len) {
> + case ETH_ALEN:
> + memcpy(&tmp.s6_addr[8], lladdr, 3);
> + tmp.s6_addr[11] = 0xFF;
> + tmp.s6_addr[12] = 0xFE;
> + memcpy(&tmp.s6_addr[13], lladdr + 3, 3);
> + break;
> + case EUI64_ADDR_LEN:
> + memcpy(&tmp.s6_addr[8], lladdr, EUI64_ADDR_LEN);
> + break;
> + default:
> + dam = LOWPAN_IPHC_DAM_11;
> + goto out;
> + }
> +
> /* second bit-flip (Universe/Local) is done according RFC2464 */
> tmp.s6_addr[8] ^= 0x02;
move this handling in per link-layer layer decision, see below.
> /* context information are always used */
PLEASE... and this is one of my rant!
PLEASE LOOK WHAT I HAVE DONE IN THIS FILE IN MY RFC PATCH SERIES YOU
NEED TO FIX MORE THAN JUST CONTEXT BASED COMPRESSION.
e.g. stateless un/compression
Now I for this, I want to see a link-layer evaluation not address length based.
Please do so also for the other patch which fixing some behaviour in ipv6.
The reason is here that uncompress/compress addresses are defined by RFC
6LoWPAN adapation.
There is already a link-layer case, so please add BTLE LLTYPE there! Not
move your handling in default, add some WARN_ONCE there...
btw:
here exists also a cleanup to not always implement the same stuff. We
need for stateful/stateless compression one function, because and
remember my words if you want to make this cleanup:
Stateless compression is stateful compression with prefix fe80::/64 as
context.
---
Sorry for my rant, but I am somehow pissed off because intel people
doesn't look what I did there in my RFC.
... I think now I know why linux kernel people do sometimes a rant. :-)
Thanks.
> diff --git a/net/bluetooth/6lowpan.c b/net/bluetooth/6lowpan.c
> index 1456b01..d2a1aa5 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);
This looks not right, you are sure that netdev->dev_addr is the
_destination_ address? It looks very confusing, because dev_addr is
normally the source address of the netdevice interface.
> }
>
> 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);
> -}
> -
YAY, this function is totally wrong! :-)
> static void ifup(struct net_device *netdev)
> {
> int err;
> @@ -762,14 +737,16 @@ static struct l2cap_chan *add_peer_chan(struct l2cap_chan *chan,
> peer->chan = chan;
> memset(&peer->peer_addr, 0, sizeof(struct in6_addr));
>
> + baswap((void *)peer->lladdr, &chan->dst);
> +
> /* 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);
>
> - memcpy(&peer->eui64_addr, (u8 *)&peer->peer_addr.s6_addr + 8,
> - EUI64_ADDR_LEN);
> + memcpy(&peer->peer_addr.s6_addr[8], peer->lladdr, 3);
> + peer->peer_addr.s6_addr[11] = 0xFF;
> + peer->peer_addr.s6_addr[12] = 0xFE;
> + memcpy(&peer->peer_addr.s6_addr[13], peer->lladdr + 3, 3);
>
What the hell is that? I suppose this is to handling something correct
to a behaviour which is another big thing which is totally broken in the
BTLE 6LoWPAN code.
> /* IPv6 address needs to have the U/L bit set properly so toggle
> * it back here.
>
- Alex
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