[PATCH net-next 0/4] 6lowpan: cleanup header creation

[PATCH net-next 0/4] 6lowpan: cleanup header creation

[Alexander Aring]

This patch series cleanup the 6LoWPAN header creation and extend the use
of skb_*_header functions.

Patch 2/4 fix issues of parsing the mac header. The ieee802.15.4 header
has a dynamic size which depends on frame control bits. This patch replaces the
static mac header len calculation with a dynamic one.

Alexander Aring (4):
  6lowpan: remove unnecessary set of headers
  6lowpan: set and use mac_len for mac header length
  6lowpan: set 6lowpan network and transport header
  6lowpan: cleanup skb copy data

 net/ieee802154/6lowpan.c | 32 +++++++++++---------------------
 net/mac802154/wpan.c     |  2 ++
 2 files changed, 13 insertions(+), 21 deletions(-)

-- 
1.8.4.2

[PATCH net-next 1/4] 6lowpan: remove unnecessary set of headers

[Alexander Aring]

On receiving side we don't need to set any headers in skb because the
6LoWPAN layer do not access it. Currently these values will set twice
after calling netif_rx.

Signed-off-by: Alexander Aring <alex.aring-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
Reviewed-by: Werner Almesberger <werner-SEdMjqphH88wryQfseakQg@public.gmane.org>
---
 net/ieee802154/6lowpan.c | 4 ----
 1 file changed, 4 deletions(-)

diff --git a/net/ieee802154/6lowpan.c b/net/ieee802154/6lowpan.c
index fde90e6..6d67784 100644
--- a/net/ieee802154/6lowpan.c
+++ b/net/ieee802154/6lowpan.c
@@ -737,7 +737,6 @@ static int lowpan_skb_deliver(struct sk_buff *skb, struct ipv6hdr *hdr)
 		return -ENOMEM;
 
 	skb_push(new, sizeof(struct ipv6hdr));
-	skb_reset_network_header(new);
 	skb_copy_to_linear_data(new, hdr, sizeof(struct ipv6hdr));
 
 	new->protocol = htons(ETH_P_IPV6);
@@ -1059,7 +1058,6 @@ lowpan_process_data(struct sk_buff *skb)
 		skb = new;
 
 		skb_push(skb, sizeof(struct udphdr));
-		skb_reset_transport_header(skb);
 		skb_copy_to_linear_data(skb, &uh, sizeof(struct udphdr));
 
 		lowpan_raw_dump_table(__func__, "raw UDP header dump",
@@ -1323,8 +1321,6 @@ static int lowpan_rcv(struct sk_buff *skb, struct net_device *dev,
 
 		/* Pull off the 1-byte of 6lowpan header. */
 		skb_pull(local_skb, 1);
-		skb_reset_network_header(local_skb);
-		skb_set_transport_header(local_skb, sizeof(struct ipv6hdr));
 
 		lowpan_give_skb_to_devices(local_skb);
 
-- 
1.8.4.2


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[PATCH net-next 2/4] 6lowpan: set and use mac_len for mac header length

[Alexander Aring]

Set the mac header length while creating the 802.15.4 mac header.

Drop the function for recalculate mac header length in upper layers
which was static and works for intra pan communication only.

Signed-off-by: Alexander Aring <alex.aring-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
Reviewed-by: Werner Almesberger <werner-SEdMjqphH88wryQfseakQg@public.gmane.org>
---
 net/ieee802154/6lowpan.c | 13 +------------
 net/mac802154/wpan.c     |  2 ++
 2 files changed, 3 insertions(+), 12 deletions(-)

diff --git a/net/ieee802154/6lowpan.c b/net/ieee802154/6lowpan.c
index 6d67784..e6db1f5 100644
--- a/net/ieee802154/6lowpan.c
+++ b/net/ieee802154/6lowpan.c
@@ -1100,17 +1100,6 @@ static int lowpan_set_address(struct net_device *dev, void *p)
 	return 0;
 }
 
-static int lowpan_get_mac_header_length(struct sk_buff *skb)
-{
-	/*
-	 * Currently long addressing mode is supported only, so the overall
-	 * header size is 21:
-	 * FC SeqNum DPAN DA  SA  Sec
-	 * 2  +  1  +  2 + 8 + 8 + 0  = 21
-	 */
-	return 21;
-}
-
 static int
 lowpan_fragment_xmit(struct sk_buff *skb, u8 *head,
 			int mlen, int plen, int offset, int type)
@@ -1150,7 +1139,7 @@ lowpan_skb_fragmentation(struct sk_buff *skb, struct net_device *dev)
 	int  err, header_length, payload_length, tag, offset = 0;
 	u8 head[5];
 
-	header_length = lowpan_get_mac_header_length(skb);
+	header_length = skb->mac_len;
 	payload_length = skb->len - header_length;
 	tag = lowpan_dev_info(dev)->fragment_tag++;
 
diff --git a/net/mac802154/wpan.c b/net/mac802154/wpan.c
index 2ca2f4d..e24bcf9 100644
--- a/net/mac802154/wpan.c
+++ b/net/mac802154/wpan.c
@@ -208,6 +208,8 @@ static int mac802154_header_create(struct sk_buff *skb,
 	head[1] = fc >> 8;
 
 	memcpy(skb_push(skb, pos), head, pos);
+	skb_reset_mac_header(skb);
+	skb->mac_len = pos;
 
 	return pos;
 }
-- 
1.8.4.2


------------------------------------------------------------------------------
Android is increasing in popularity, but the open development platform that
developers love is also attractive to malware creators. Download this white
paper to learn more about secure code signing practices that can help keep
Android apps secure.
http://pubads.g.doubleclick.net/gampad/clk?id=65839951&iu=/4140/ostg.clktrk

[PATCH net-next 3/4] 6lowpan: set 6lowpan network and transport header

[Alexander Aring]

This is necessary to access network header with the skb_network_header
function instead of calculate the position with mac_len, etc.
Do the same for the transport header, when we replace the IPv6 header
with the 6LoWPAN header.

Signed-off-by: Alexander Aring <alex.aring@gmail.com>
Acked-by: Werner Almesberger <werner@almesberger.net>
---
 net/ieee802154/6lowpan.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/net/ieee802154/6lowpan.c b/net/ieee802154/6lowpan.c
index e6db1f5..58c07fd 100644
--- a/net/ieee802154/6lowpan.c
+++ b/net/ieee802154/6lowpan.c
@@ -654,7 +654,9 @@ static int lowpan_header_create(struct sk_buff *skb,
 	head[1] = iphc1;
 
 	skb_pull(skb, sizeof(struct ipv6hdr));
+	skb_reset_transport_header(skb);
 	memcpy(skb_push(skb, hc06_ptr - head), head, hc06_ptr - head);
+	skb_reset_network_header(skb);
 
 	lowpan_raw_dump_table(__func__, "raw skb data dump", skb->data,
 				skb->len);
-- 
1.8.4.2

[PATCH net-next 4/4] 6lowpan: cleanup skb copy data

[Alexander Aring]

This patch drops the direct memcpy on skb and uses the right skb
memcpy functions. Also remove an unnecessary check if plen is non zero.

Signed-off-by: Alexander Aring <alex.aring@gmail.com>
Reviewed-by: Werner Almesberger <werner@almesberger.net>
---
 net/ieee802154/6lowpan.c | 13 ++++++++-----
 1 file changed, 8 insertions(+), 5 deletions(-)

diff --git a/net/ieee802154/6lowpan.c b/net/ieee802154/6lowpan.c
index 58c07fd..9497c6f 100644
--- a/net/ieee802154/6lowpan.c
+++ b/net/ieee802154/6lowpan.c
@@ -1122,12 +1122,15 @@ lowpan_fragment_xmit(struct sk_buff *skb, u8 *head,
 	frag->priority = skb->priority;
 
 	/* copy header, MFR and payload */
-	memcpy(skb_put(frag, mlen), skb->data, mlen);
-	memcpy(skb_put(frag, hlen), head, hlen);
+	skb_put(frag, mlen);
+	skb_copy_to_linear_data(frag, skb_mac_header(skb), mlen);
 
-	if (plen)
-		skb_copy_from_linear_data_offset(skb, offset + mlen,
-					skb_put(frag, plen), plen);
+	skb_put(frag, hlen);
+	skb_copy_to_linear_data_offset(frag, mlen, head, hlen);
+
+	skb_put(frag, plen);
+	skb_copy_to_linear_data_offset(frag, mlen + hlen,
+				       skb_network_header(skb) + offset, plen);
 
 	lowpan_raw_dump_table(__func__, " raw fragment dump", frag->data,
 								frag->len);
-- 
1.8.4.2

Re: [PATCH net-next 0/4] 6lowpan: cleanup header creation

[David Miller]

From: Alexander Aring <alex.aring@gmail.com>
Date: Wed, 30 Oct 2013 09:18:20 +0100

> This patch series cleanup the 6LoWPAN header creation and extend the use
> of skb_*_header functions.
> 
> Patch 2/4 fix issues of parsing the mac header. The ieee802.15.4 header
> has a dynamic size which depends on frame control bits. This patch replaces the
> static mac header len calculation with a dynamic one.

Series applied, thanks.