diff options
| author | alex.bluesman.smirnov@gmail.com <alex.bluesman.smirnov@gmail.com> | 2011-11-10 07:40:53 +0000 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2011-11-14 00:19:43 -0500 |
| commit | f8b1b5d231c6db03f87e9db195530156fde47c4b (patch) | |
| tree | e8292bc28ee50bcdb11f436f920a4ac3289757a1 /net/ieee802154/6lowpan.c | |
| parent | 3bd5b958c2a2dd1a9b4c8d21e75fb47b062fc941 (diff) | |
6LoWPAN: UDP header decompression
This patch provides possibility to decompress UDP headers.
Derived from Contiki OS.
Signed-off-by: Alexander Smirnov <alex.bluesman.smirnov@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/ieee802154/6lowpan.c')
| -rw-r--r-- | net/ieee802154/6lowpan.c | 61 |
1 files changed, 60 insertions, 1 deletions
diff --git a/net/ieee802154/6lowpan.c b/net/ieee802154/6lowpan.c index 9bf82d72bb9..602f318a8d6 100644 --- a/net/ieee802154/6lowpan.c +++ b/net/ieee802154/6lowpan.c @@ -311,6 +311,62 @@ static u16 lowpan_fetch_skb_u16(struct sk_buff *skb) return ret; } +static int +lowpan_uncompress_udp_header(struct sk_buff *skb) +{ + struct udphdr *uh = udp_hdr(skb); + u8 tmp; + + tmp = lowpan_fetch_skb_u8(skb); + + if ((tmp & LOWPAN_NHC_UDP_MASK) == LOWPAN_NHC_UDP_ID) { + pr_debug("(%s): UDP header uncompression\n", __func__); + switch (tmp & LOWPAN_NHC_UDP_CS_P_11) { + case LOWPAN_NHC_UDP_CS_P_00: + memcpy(&uh->source, &skb->data[0], 2); + memcpy(&uh->dest, &skb->data[2], 2); + skb_pull(skb, 4); + break; + case LOWPAN_NHC_UDP_CS_P_01: + memcpy(&uh->source, &skb->data[0], 2); + uh->dest = + skb->data[2] + LOWPAN_NHC_UDP_8BIT_PORT; + skb_pull(skb, 3); + break; + case LOWPAN_NHC_UDP_CS_P_10: + uh->source = skb->data[0] + LOWPAN_NHC_UDP_8BIT_PORT; + memcpy(&uh->dest, &skb->data[1], 2); + skb_pull(skb, 3); + break; + case LOWPAN_NHC_UDP_CS_P_11: + uh->source = + LOWPAN_NHC_UDP_4BIT_PORT + (skb->data[0] >> 4); + uh->dest = + LOWPAN_NHC_UDP_4BIT_PORT + (skb->data[0] & 0x0f); + skb_pull(skb, 1); + break; + default: + pr_debug("(%s) ERROR: unknown UDP format\n", __func__); + goto err; + break; + } + + pr_debug("(%s): uncompressed UDP ports: src = %d, dst = %d\n", + __func__, uh->source, uh->dest); + + /* copy checksum */ + memcpy(&uh->check, &skb->data[0], 2); + skb_pull(skb, 2); + } else { + pr_debug("(%s): ERROR: unsupported NH format\n", __func__); + goto err; + } + + return 0; +err: + return -EINVAL; +} + static int lowpan_header_create(struct sk_buff *skb, struct net_device *dev, unsigned short type, const void *_daddr, @@ -842,7 +898,10 @@ lowpan_process_data(struct sk_buff *skb) goto drop; } - /* TODO: UDP header parse */ + /* UDP data uncompression */ + if (iphc0 & LOWPAN_IPHC_NH_C) + if (lowpan_uncompress_udp_header(skb)) + goto drop; /* Not fragmented package */ hdr.payload_len = htons(skb->len); |