diff options
| -rw-r--r-- | net/ieee802154/6lowpan.c | 51 | ||||
| -rw-r--r-- | net/ieee802154/6lowpan.h | 5 |
2 files changed, 52 insertions, 4 deletions
diff --git a/net/ieee802154/6lowpan.c b/net/ieee802154/6lowpan.c index 39ec6e0..9bf82d7 100644 --- a/net/ieee802154/6lowpan.c +++ b/net/ieee802154/6lowpan.c @@ -246,6 +246,50 @@ lowpan_uncompress_addr(struct sk_buff *skb, struct in6_addr *ipaddr, return 0; } +static void +lowpan_compress_udp_header(u8 **hc06_ptr, struct sk_buff *skb) +{ + struct udphdr *uh = udp_hdr(skb); + + pr_debug("(%s): UDP header compression\n", __func__); + + if (((uh->source & LOWPAN_NHC_UDP_4BIT_MASK) == + LOWPAN_NHC_UDP_4BIT_PORT) && + ((uh->dest & LOWPAN_NHC_UDP_4BIT_MASK) == + LOWPAN_NHC_UDP_4BIT_PORT)) { + pr_debug("(%s): both ports compression to 4 bits\n", __func__); + **hc06_ptr = LOWPAN_NHC_UDP_CS_P_11; + **(hc06_ptr + 1) = /* subtraction is faster */ + (u8)((uh->dest - LOWPAN_NHC_UDP_4BIT_PORT) + + ((uh->source & LOWPAN_NHC_UDP_4BIT_PORT) << 4)); + *hc06_ptr += 2; + } else if ((uh->dest & LOWPAN_NHC_UDP_8BIT_MASK) == + LOWPAN_NHC_UDP_8BIT_PORT) { + pr_debug("(%s): remove 8 bits of dest\n", __func__); + **hc06_ptr = LOWPAN_NHC_UDP_CS_P_01; + memcpy(*hc06_ptr + 1, &uh->source, 2); + **(hc06_ptr + 3) = (u8)(uh->dest - LOWPAN_NHC_UDP_8BIT_PORT); + *hc06_ptr += 4; + } else if ((uh->source & LOWPAN_NHC_UDP_8BIT_MASK) == + LOWPAN_NHC_UDP_8BIT_PORT) { + pr_debug("(%s): remove 8 bits of source\n", __func__); + **hc06_ptr = LOWPAN_NHC_UDP_CS_P_10; + memcpy(*hc06_ptr + 1, &uh->dest, 2); + **(hc06_ptr + 3) = (u8)(uh->source - LOWPAN_NHC_UDP_8BIT_PORT); + *hc06_ptr += 4; + } else { + pr_debug("(%s): can't compress header\n", __func__); + **hc06_ptr = LOWPAN_NHC_UDP_CS_P_00; + memcpy(*hc06_ptr + 1, &uh->source, 2); + memcpy(*hc06_ptr + 3, &uh->dest, 2); + *hc06_ptr += 5; + } + + /* checksum is always inline */ + memcpy(*hc06_ptr, &uh->check, 2); + *hc06_ptr += 2; +} + static u8 lowpan_fetch_skb_u8(struct sk_buff *skb) { u8 ret; @@ -365,8 +409,6 @@ static int lowpan_header_create(struct sk_buff *skb, if (hdr->nexthdr == UIP_PROTO_UDP) iphc0 |= LOWPAN_IPHC_NH_C; -/* TODO: next header compression */ - if ((iphc0 & LOWPAN_IPHC_NH_C) == 0) { *hc06_ptr = hdr->nexthdr; hc06_ptr += 1; @@ -454,8 +496,9 @@ static int lowpan_header_create(struct sk_buff *skb, } } - /* TODO: UDP header compression */ - /* TODO: Next Header compression */ + /* UDP header compression */ + if (hdr->nexthdr == UIP_PROTO_UDP) + lowpan_compress_udp_header(&hc06_ptr, skb); head[0] = iphc0; head[1] = iphc1; diff --git a/net/ieee802154/6lowpan.h b/net/ieee802154/6lowpan.h index 5d2e5a0..aeff3f3 100644 --- a/net/ieee802154/6lowpan.h +++ b/net/ieee802154/6lowpan.h @@ -219,6 +219,11 @@ #define LOWPAN_NHC_UDP_CHECKSUMC 0x04 #define LOWPAN_NHC_UDP_CHECKSUMI 0x00 +#define LOWPAN_NHC_UDP_4BIT_PORT 0xF0B0 +#define LOWPAN_NHC_UDP_4BIT_MASK 0xFFF0 +#define LOWPAN_NHC_UDP_8BIT_PORT 0xF000 +#define LOWPAN_NHC_UDP_8BIT_MASK 0xFF00 + /* values for port compression, _with checksum_ ie bit 5 set to 0 */ #define LOWPAN_NHC_UDP_CS_P_00 0xF0 /* all inline */ #define LOWPAN_NHC_UDP_CS_P_01 0xF1 /* source 16bit inline, |
