6lowpan: Moving generic compression code into 6lowpan_iphc.c

Because the IEEE 802154 and Bluetooth share the IP header compression
and uncompression code, the common code is moved to 6lowpan_iphc.c
file.

Signed-off-by: Jukka Rissanen <jukka.rissanen@linux.intel.com>
Acked-by: Alexander Aring <alex.aring@gmail.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

1 files changed, 35 insertions, 718 deletions

diff --git a/net/ieee802154/6lowpan.c b/net/ieee802154/6lowpan.c
index 459e200c08a4..53d0bd58ed8d 100644
--- a/net/ieee802154/6lowpan.c
+++ b/net/ieee802154/6lowpan.c
@@ -62,9 +62,6 @@
 
 #include "6lowpan.h"
 
-/* TTL uncompression values */
-static const u8 lowpan_ttl_values[] = {0, 1, 64, 255};
-
 static LIST_HEAD(lowpan_devices);
 
 /* private device info */
@@ -135,347 +132,14 @@ static inline void lowpan_raw_dump_table(const char *caller, char *msg,
 #endif /* DEBUG */
 }
 
-static u8
-lowpan_compress_addr_64(u8 **hc06_ptr, u8 shift, const struct in6_addr *ipaddr,
-                 const unsigned char *lladdr)
-{
-        u8 val = 0;
-
-        if (is_addr_mac_addr_based(ipaddr, lladdr))
-                val = 3; /* 0-bits */
-        else if (lowpan_is_iid_16_bit_compressable(ipaddr)) {
-                /* compress IID to 16 bits xxxx::XXXX */
-                memcpy(*hc06_ptr, &ipaddr->s6_addr16[7], 2);
-                *hc06_ptr += 2;
-                val = 2; /* 16-bits */
-        } else {
-                /* do not compress IID => xxxx::IID */
-                memcpy(*hc06_ptr, &ipaddr->s6_addr16[4], 8);
-                *hc06_ptr += 8;
-                val = 1; /* 64-bits */
-        }
-
-        return rol8(val, shift);
-}
-
-/*
- * Uncompress address function for source and
- * destination address(non-multicast).
- *
- * address_mode is sam value or dam value.
- */
-static int
-lowpan_uncompress_addr(struct sk_buff *skb,
-                struct in6_addr *ipaddr,
-                const u8 address_mode,
-                const struct ieee802154_addr *lladdr)
-{
-        bool fail;
-
-        switch (address_mode) {
-        case LOWPAN_IPHC_ADDR_00:
-                /* for global link addresses */
-                fail = lowpan_fetch_skb(skb, ipaddr->s6_addr, 16);
-                break;
-        case LOWPAN_IPHC_ADDR_01:
-                /* fe:80::XXXX:XXXX:XXXX:XXXX */
-                ipaddr->s6_addr[0] = 0xFE;
-                ipaddr->s6_addr[1] = 0x80;
-                fail = lowpan_fetch_skb(skb, &ipaddr->s6_addr[8], 8);
-                break;
-        case LOWPAN_IPHC_ADDR_02:
-                /* fe:80::ff:fe00:XXXX */
-                ipaddr->s6_addr[0] = 0xFE;
-                ipaddr->s6_addr[1] = 0x80;
-                ipaddr->s6_addr[11] = 0xFF;
-                ipaddr->s6_addr[12] = 0xFE;
-                fail = lowpan_fetch_skb(skb, &ipaddr->s6_addr[14], 2);
-                break;
-        case LOWPAN_IPHC_ADDR_03:
-                fail = false;
-                switch (lladdr->addr_type) {
-                case IEEE802154_ADDR_LONG:
-                        /* fe:80::XXXX:XXXX:XXXX:XXXX
-                         *        \_________________/
-                         *              hwaddr
-                         */
-                        ipaddr->s6_addr[0] = 0xFE;
-                        ipaddr->s6_addr[1] = 0x80;
-                        memcpy(&ipaddr->s6_addr[8], lladdr->hwaddr,
-                                        IEEE802154_ADDR_LEN);
-                        /* second bit-flip (Universe/Local)
-                         * is done according RFC2464
-                         */
-                        ipaddr->s6_addr[8] ^= 0x02;
-                        break;
-                case IEEE802154_ADDR_SHORT:
-                        /* fe:80::ff:fe00:XXXX
-                         *                \__/
-                         *             short_addr
-                         *
-                         * Universe/Local bit is zero.
-                         */
-                        ipaddr->s6_addr[0] = 0xFE;
-                        ipaddr->s6_addr[1] = 0x80;
-                        ipaddr->s6_addr[11] = 0xFF;
-                        ipaddr->s6_addr[12] = 0xFE;
-                        ipaddr->s6_addr16[7] = htons(lladdr->short_addr);
-                        break;
-                default:
-                        pr_debug("Invalid addr_type set\n");
-                        return -EINVAL;
-                }
-                break;
-        default:
-                pr_debug("Invalid address mode value: 0x%x\n", address_mode);
-                return -EINVAL;
-        }
-
-        if (fail) {
-                pr_debug("Failed to fetch skb data\n");
-                return -EIO;
-        }
-
-        lowpan_raw_dump_inline(NULL, "Reconstructed ipv6 addr is:\n",
-                        ipaddr->s6_addr, 16);
-
-        return 0;
-}
-
-/* Uncompress address function for source context
- * based address(non-multicast).
- */
-static int
-lowpan_uncompress_context_based_src_addr(struct sk_buff *skb,
-                struct in6_addr *ipaddr,
-                const u8 sam)
-{
-        switch (sam) {
-        case LOWPAN_IPHC_ADDR_00:
-                /* unspec address ::
-                 * Do nothing, address is already ::
-                 */
-                break;
-        case LOWPAN_IPHC_ADDR_01:
-                /* TODO */
-        case LOWPAN_IPHC_ADDR_02:
-                /* TODO */
-        case LOWPAN_IPHC_ADDR_03:
-                /* TODO */
-                netdev_warn(skb->dev, "SAM value 0x%x not supported\n", sam);
-                return -EINVAL;
-        default:
-                pr_debug("Invalid sam value: 0x%x\n", sam);
-                return -EINVAL;
-        }
-
-        lowpan_raw_dump_inline(NULL,
-                        "Reconstructed context based ipv6 src addr is:\n",
-                        ipaddr->s6_addr, 16);
-
-        return 0;
-}
-
-/* Uncompress function for multicast destination address,
- * when M bit is set.
- */
-static int
-lowpan_uncompress_multicast_daddr(struct sk_buff *skb,
-                struct in6_addr *ipaddr,
-                const u8 dam)
-{
-        bool fail;
-
-        switch (dam) {
-        case LOWPAN_IPHC_DAM_00:
-                /* 00:  128 bits.  The full address
-                 * is carried in-line.
-                 */
-                fail = lowpan_fetch_skb(skb, ipaddr->s6_addr, 16);
-                break;
-        case LOWPAN_IPHC_DAM_01:
-                /* 01:  48 bits.  The address takes
-                 * the form ffXX::00XX:XXXX:XXXX.
-                 */
-                ipaddr->s6_addr[0] = 0xFF;
-                fail = lowpan_fetch_skb(skb, &ipaddr->s6_addr[1], 1);
-                fail |= lowpan_fetch_skb(skb, &ipaddr->s6_addr[11], 5);
-                break;
-        case LOWPAN_IPHC_DAM_10:
-                /* 10:  32 bits.  The address takes
-                 * the form ffXX::00XX:XXXX.
-                 */
-                ipaddr->s6_addr[0] = 0xFF;
-                fail = lowpan_fetch_skb(skb, &ipaddr->s6_addr[1], 1);
-                fail |= lowpan_fetch_skb(skb, &ipaddr->s6_addr[13], 3);
-                break;
-        case LOWPAN_IPHC_DAM_11:
-                /* 11:  8 bits.  The address takes
-                 * the form ff02::00XX.
-                 */
-                ipaddr->s6_addr[0] = 0xFF;
-                ipaddr->s6_addr[1] = 0x02;
-                fail = lowpan_fetch_skb(skb, &ipaddr->s6_addr[15], 1);
-                break;
-        default:
-                pr_debug("DAM value has a wrong value: 0x%x\n", dam);
-                return -EINVAL;
-        }
-
-        if (fail) {
-                pr_debug("Failed to fetch skb data\n");
-                return -EIO;
-        }
-
-        lowpan_raw_dump_inline(NULL, "Reconstructed ipv6 multicast addr is:\n",
-                        ipaddr->s6_addr, 16);
-
-        return 0;
-}
-
-static void
-lowpan_compress_udp_header(u8 **hc06_ptr, struct sk_buff *skb)
-{
-        struct udphdr *uh = udp_hdr(skb);
-
-        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("UDP header: both ports compression to 4 bits\n");
-                **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("UDP header: remove 8 bits of dest\n");
-                **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("UDP header: remove 8 bits of source\n");
-                **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("UDP header: can't compress\n");
-                **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;
-
-        /* skip the UDP header */
-        skb_pull(skb, sizeof(struct udphdr));
-}
-
-static inline int lowpan_fetch_skb_u8(struct sk_buff *skb, u8 *val)
-{
-        if (unlikely(!pskb_may_pull(skb, 1)))
-                return -EINVAL;
-
-        *val = skb->data[0];
-        skb_pull(skb, 1);
-
-        return 0;
-}
-
-static inline int lowpan_fetch_skb_u16(struct sk_buff *skb, u16 *val)
-{
-        if (unlikely(!pskb_may_pull(skb, 2)))
-                return -EINVAL;
-
-        *val = (skb->data[0] << 8) | skb->data[1];
-        skb_pull(skb, 2);
-
-        return 0;
-}
-
-static int
-lowpan_uncompress_udp_header(struct sk_buff *skb, struct udphdr *uh)
-{
-        u8 tmp;
-
-        if (!uh)
-                goto err;
-
-        if (lowpan_fetch_skb_u8(skb, &tmp))
-                goto err;
-
-        if ((tmp & LOWPAN_NHC_UDP_MASK) == LOWPAN_NHC_UDP_ID) {
-                pr_debug("UDP header uncompression\n");
-                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("ERROR: unknown UDP format\n");
-                        goto err;
-                }
-
-                pr_debug("uncompressed UDP ports: src = %d, dst = %d\n",
-                         uh->source, uh->dest);
-
-                /* copy checksum */
-                memcpy(&uh->check, &skb->data[0], 2);
-                skb_pull(skb, 2);
-
-                /*
-                 * UDP lenght needs to be infered from the lower layers
-                 * here, we obtain the hint from the remaining size of the
-                 * frame
-                 */
-                uh->len = htons(skb->len + sizeof(struct udphdr));
-                pr_debug("uncompressed UDP length: src = %d", uh->len);
-        } else {
-                pr_debug("ERROR: unsupported NH format\n");
-                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,
                            const void *_saddr, unsigned int len)
 {
-        u8 tmp, iphc0, iphc1, *hc06_ptr;
         struct ipv6hdr *hdr;
         const u8 *saddr = _saddr;
         const u8 *daddr = _daddr;
-        u8 head[100];
         struct ieee802154_addr sa, da;
 
         /* TODO:
@@ -485,181 +149,14 @@ static int lowpan_header_create(struct sk_buff *skb,
                 return 0;
 
         hdr = ipv6_hdr(skb);
-        hc06_ptr = head + 2;
-
-        pr_debug("IPv6 header dump:\n\tversion = %d\n\tlength  = %d\n"
-                 "\tnexthdr = 0x%02x\n\thop_lim = %d\n", hdr->version,
-                 ntohs(hdr->payload_len), hdr->nexthdr, hdr->hop_limit);
-
-        lowpan_raw_dump_table(__func__, "raw skb network header dump",
-                skb_network_header(skb), sizeof(struct ipv6hdr));
 
         if (!saddr)
                 saddr = dev->dev_addr;
 
         lowpan_raw_dump_inline(__func__, "saddr", (unsigned char *)saddr, 8);
-
-        /*
-         * As we copy some bit-length fields, in the IPHC encoding bytes,
-         * we sometimes use |=
-         * If the field is 0, and the current bit value in memory is 1,
-         * this does not work. We therefore reset the IPHC encoding here
-         */
-        iphc0 = LOWPAN_DISPATCH_IPHC;
-        iphc1 = 0;
-
-        /* TODO: context lookup */
-
         lowpan_raw_dump_inline(__func__, "daddr", (unsigned char *)daddr, 8);
 
-        /*
-         * Traffic class, flow label
-         * If flow label is 0, compress it. If traffic class is 0, compress it
-         * We have to process both in the same time as the offset of traffic
-         * class depends on the presence of version and flow label
-         */
-
-        /* hc06 format of TC is ECN | DSCP , original one is DSCP | ECN */
-        tmp = (hdr->priority << 4) | (hdr->flow_lbl[0] >> 4);
-        tmp = ((tmp & 0x03) << 6) | (tmp >> 2);
-
-        if (((hdr->flow_lbl[0] & 0x0F) == 0) &&
-             (hdr->flow_lbl[1] == 0) && (hdr->flow_lbl[2] == 0)) {
-                /* flow label can be compressed */
-                iphc0 |= LOWPAN_IPHC_FL_C;
-                if ((hdr->priority == 0) &&
-                   ((hdr->flow_lbl[0] & 0xF0) == 0)) {
-                        /* compress (elide) all */
-                        iphc0 |= LOWPAN_IPHC_TC_C;
-                } else {
-                        /* compress only the flow label */
-                        *hc06_ptr = tmp;
-                        hc06_ptr += 1;
-                }
-        } else {
-                /* Flow label cannot be compressed */
-                if ((hdr->priority == 0) &&
-                   ((hdr->flow_lbl[0] & 0xF0) == 0)) {
-                        /* compress only traffic class */
-                        iphc0 |= LOWPAN_IPHC_TC_C;
-                        *hc06_ptr = (tmp & 0xc0) | (hdr->flow_lbl[0] & 0x0F);
-                        memcpy(hc06_ptr + 1, &hdr->flow_lbl[1], 2);
-                        hc06_ptr += 3;
-                } else {
-                        /* compress nothing */
-                        memcpy(hc06_ptr, &hdr, 4);
-                        /* replace the top byte with new ECN | DSCP format */
-                        *hc06_ptr = tmp;
-                        hc06_ptr += 4;
-                }
-        }
-
-        /* NOTE: payload length is always compressed */
-
-        /* Next Header is compress if UDP */
-        if (hdr->nexthdr == UIP_PROTO_UDP)
-                iphc0 |= LOWPAN_IPHC_NH_C;
-
-        if ((iphc0 & LOWPAN_IPHC_NH_C) == 0) {
-                *hc06_ptr = hdr->nexthdr;
-                hc06_ptr += 1;
-        }
-
-        /*
-         * Hop limit
-         * if 1:   compress, encoding is 01
-         * if 64:  compress, encoding is 10
-         * if 255: compress, encoding is 11
-         * else do not compress
-         */
-        switch (hdr->hop_limit) {
-        case 1:
-                iphc0 |= LOWPAN_IPHC_TTL_1;
-                break;
-        case 64:
-                iphc0 |= LOWPAN_IPHC_TTL_64;
-                break;
-        case 255:
-                iphc0 |= LOWPAN_IPHC_TTL_255;
-                break;
-        default:
-                *hc06_ptr = hdr->hop_limit;
-                hc06_ptr += 1;
-                break;
-        }
-
-        /* source address compression */
-        if (is_addr_unspecified(&hdr->saddr)) {
-                pr_debug("source address is unspecified, setting SAC\n");
-                iphc1 |= LOWPAN_IPHC_SAC;
-        /* TODO: context lookup */
-        } else if (is_addr_link_local(&hdr->saddr)) {
-                pr_debug("source address is link-local\n");
-                iphc1 |= lowpan_compress_addr_64(&hc06_ptr,
-                                LOWPAN_IPHC_SAM_BIT, &hdr->saddr, saddr);
-        } else {
-                pr_debug("send the full source address\n");
-                memcpy(hc06_ptr, &hdr->saddr.s6_addr16[0], 16);
-                hc06_ptr += 16;
-        }
-
-        /* destination address compression */
-        if (is_addr_mcast(&hdr->daddr)) {
-                pr_debug("destination address is multicast: ");
-                iphc1 |= LOWPAN_IPHC_M;
-                if (lowpan_is_mcast_addr_compressable8(&hdr->daddr)) {
-                        pr_debug("compressed to 1 octet\n");
-                        iphc1 |= LOWPAN_IPHC_DAM_11;
-                        /* use last byte */
-                        *hc06_ptr = hdr->daddr.s6_addr[15];
-                        hc06_ptr += 1;
-                } else if (lowpan_is_mcast_addr_compressable32(&hdr->daddr)) {
-                        pr_debug("compressed to 4 octets\n");
-                        iphc1 |= LOWPAN_IPHC_DAM_10;
-                        /* second byte + the last three */
-                        *hc06_ptr = hdr->daddr.s6_addr[1];
-                        memcpy(hc06_ptr + 1, &hdr->daddr.s6_addr[13], 3);
-                        hc06_ptr += 4;
-                } else if (lowpan_is_mcast_addr_compressable48(&hdr->daddr)) {
-                        pr_debug("compressed to 6 octets\n");
-                        iphc1 |= LOWPAN_IPHC_DAM_01;
-                        /* second byte + the last five */
-                        *hc06_ptr = hdr->daddr.s6_addr[1];
-                        memcpy(hc06_ptr + 1, &hdr->daddr.s6_addr[11], 5);
-                        hc06_ptr += 6;
-                } else {
-                        pr_debug("using full address\n");
-                        iphc1 |= LOWPAN_IPHC_DAM_00;
-                        memcpy(hc06_ptr, &hdr->daddr.s6_addr[0], 16);
-                        hc06_ptr += 16;
-                }
-        } else {
-                /* TODO: context lookup */
-                if (is_addr_link_local(&hdr->daddr)) {
-                        pr_debug("dest address is unicast and link-local\n");
-                        iphc1 |= lowpan_compress_addr_64(&hc06_ptr,
-                                LOWPAN_IPHC_DAM_BIT, &hdr->daddr, daddr);
-                } else {
-                        pr_debug("dest address is unicast: using full one\n");
-                        memcpy(hc06_ptr, &hdr->daddr.s6_addr16[0], 16);
-                        hc06_ptr += 16;
-                }
-        }
-
-        /* UDP header compression */
-        if (hdr->nexthdr == UIP_PROTO_UDP)
-                lowpan_compress_udp_header(&hc06_ptr, skb);
-
-        head[0] = iphc0;
-        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);
+        lowpan_header_compress(skb, dev, type, daddr, saddr, len);
 
         /*
          * NOTE1: I'm still unsure about the fact that compression and WPAN
@@ -671,39 +168,38 @@ static int lowpan_header_create(struct sk_buff *skb,
          * from MAC subif of the 'dev' and 'real_dev' network devices, but
          * this isn't implemented in mainline yet, so currently we assign 0xff
          */
-        {
-                mac_cb(skb)->flags = IEEE802154_FC_TYPE_DATA;
-                mac_cb(skb)->seq = ieee802154_mlme_ops(dev)->get_dsn(dev);
+        mac_cb(skb)->flags = IEEE802154_FC_TYPE_DATA;
+        mac_cb(skb)->seq = ieee802154_mlme_ops(dev)->get_dsn(dev);
 
-                /* prepare wpan address data */
-                sa.addr_type = IEEE802154_ADDR_LONG;
-                sa.pan_id = ieee802154_mlme_ops(dev)->get_pan_id(dev);
+        /* prepare wpan address data */
+        sa.addr_type = IEEE802154_ADDR_LONG;
+        sa.pan_id = ieee802154_mlme_ops(dev)->get_pan_id(dev);
 
-                memcpy(&(sa.hwaddr), saddr, 8);
-                /* intra-PAN communications */
-                da.pan_id = ieee802154_mlme_ops(dev)->get_pan_id(dev);
+        memcpy(&(sa.hwaddr), saddr, 8);
+        /* intra-PAN communications */
+        da.pan_id = ieee802154_mlme_ops(dev)->get_pan_id(dev);
 
-                /*
-                 * if the destination address is the broadcast address, use the
-                 * corresponding short address
-                 */
-                if (lowpan_is_addr_broadcast(daddr)) {
-                        da.addr_type = IEEE802154_ADDR_SHORT;
-                        da.short_addr = IEEE802154_ADDR_BROADCAST;
-                } else {
-                        da.addr_type = IEEE802154_ADDR_LONG;
-                        memcpy(&(da.hwaddr), daddr, IEEE802154_ADDR_LEN);
-
-                        /* request acknowledgment */
-                        mac_cb(skb)->flags |= MAC_CB_FLAG_ACKREQ;
-                }
+        /*
+         * if the destination address is the broadcast address, use the
+         * corresponding short address
+         */
+        if (lowpan_is_addr_broadcast(daddr)) {
+                da.addr_type = IEEE802154_ADDR_SHORT;
+                da.short_addr = IEEE802154_ADDR_BROADCAST;
+        } else {
+                da.addr_type = IEEE802154_ADDR_LONG;
+                memcpy(&(da.hwaddr), daddr, IEEE802154_ADDR_LEN);
 
-                return dev_hard_header(skb, lowpan_dev_info(dev)->real_dev,
-                                type, (void *)&da, (void *)&sa, skb->len);
+                /* request acknowledgment */
+                mac_cb(skb)->flags |= MAC_CB_FLAG_ACKREQ;
         }
+
+        return dev_hard_header(skb, lowpan_dev_info(dev)->real_dev,
+                        type, (void *)&da, (void *)&sa, skb->len);
 }
 
-static int lowpan_give_skb_to_devices(struct sk_buff *skb)
+static int lowpan_give_skb_to_devices(struct sk_buff *skb,
+                                        struct net_device *dev)
 {
         struct lowpan_dev_record *entry;
         struct sk_buff *skb_cp;
@@ -726,31 +222,6 @@ static int lowpan_give_skb_to_devices(struct sk_buff *skb)
         return stat;
 }
 
-static int lowpan_skb_deliver(struct sk_buff *skb, struct ipv6hdr *hdr)
-{
-        struct sk_buff *new;
-        int stat = NET_RX_SUCCESS;
-
-        new = skb_copy_expand(skb, sizeof(struct ipv6hdr), skb_tailroom(skb),
-                                                                GFP_ATOMIC);
-        kfree_skb(skb);
-
-        if (!new)
-                return -ENOMEM;
-
-        skb_push(new, sizeof(struct ipv6hdr));
-        skb_copy_to_linear_data(new, hdr, sizeof(struct ipv6hdr));
-
-        new->protocol = htons(ETH_P_IPV6);
-        new->pkt_type = PACKET_HOST;
-
-        stat = lowpan_give_skb_to_devices(new);
-
-        kfree_skb(new);
-
-        return stat;
-}
-
 static void lowpan_fragment_timer_expired(unsigned long entry_addr)
 {
         struct lowpan_fragment *entry = (struct lowpan_fragment *)entry_addr;
@@ -814,13 +285,10 @@ frame_err:
         return NULL;
 }
 
-static int
-lowpan_process_data(struct sk_buff *skb)
+static int process_data(struct sk_buff *skb)
 {
-        struct ipv6hdr hdr = {};
-        u8 tmp, iphc0, iphc1, num_context = 0;
+        u8 iphc0, iphc1;
         const struct ieee802154_addr *_saddr, *_daddr;
-        int err;
 
         lowpan_raw_dump_table(__func__, "raw skb data dump", skb->data,
                                 skb->len);
@@ -925,162 +393,11 @@ lowpan_process_data(struct sk_buff *skb)
         _saddr = &mac_cb(skb)->sa;
         _daddr = &mac_cb(skb)->da;
 
-        pr_debug("iphc0 = %02x, iphc1 = %02x\n", iphc0, iphc1);
-
-        /* another if the CID flag is set */
-        if (iphc1 & LOWPAN_IPHC_CID) {
-                pr_debug("CID flag is set, increase header with one\n");
-                if (lowpan_fetch_skb_u8(skb, &num_context))
-                        goto drop;
-        }
-
-        hdr.version = 6;
-
-        /* Traffic Class and Flow Label */
-        switch ((iphc0 & LOWPAN_IPHC_TF) >> 3) {
-        /*
-         * Traffic Class and FLow Label carried in-line
-         * ECN + DSCP + 4-bit Pad + Flow Label (4 bytes)
-         */
-        case 0: /* 00b */
-                if (lowpan_fetch_skb_u8(skb, &tmp))
-                        goto drop;
-
-                memcpy(&hdr.flow_lbl, &skb->data[0], 3);
-                skb_pull(skb, 3);
-                hdr.priority = ((tmp >> 2) & 0x0f);
-                hdr.flow_lbl[0] = ((tmp >> 2) & 0x30) | (tmp << 6) |
-                                        (hdr.flow_lbl[0] & 0x0f);
-                break;
-        /*
-         * Traffic class carried in-line
-         * ECN + DSCP (1 byte), Flow Label is elided
-         */
-        case 2: /* 10b */
-                if (lowpan_fetch_skb_u8(skb, &tmp))
-                        goto drop;
-
-                hdr.priority = ((tmp >> 2) & 0x0f);
-                hdr.flow_lbl[0] = ((tmp << 6) & 0xC0) | ((tmp >> 2) & 0x30);
-                break;
-        /*
-         * Flow Label carried in-line
-         * ECN + 2-bit Pad + Flow Label (3 bytes), DSCP is elided
-         */
-        case 1: /* 01b */
-                if (lowpan_fetch_skb_u8(skb, &tmp))
-                        goto drop;
-
-                hdr.flow_lbl[0] = (skb->data[0] & 0x0F) | ((tmp >> 2) & 0x30);
-                memcpy(&hdr.flow_lbl[1], &skb->data[0], 2);
-                skb_pull(skb, 2);
-                break;
-        /* Traffic Class and Flow Label are elided */
-        case 3: /* 11b */
-                break;
-        default:
-                break;
-        }
-
-        /* Next Header */
-        if ((iphc0 & LOWPAN_IPHC_NH_C) == 0) {
-                /* Next header is carried inline */
-                if (lowpan_fetch_skb_u8(skb, &(hdr.nexthdr)))
-                        goto drop;
-
-                pr_debug("NH flag is set, next header carried inline: %02x\n",
-                         hdr.nexthdr);
-        }
-
-        /* Hop Limit */
-        if ((iphc0 & 0x03) != LOWPAN_IPHC_TTL_I)
-                hdr.hop_limit = lowpan_ttl_values[iphc0 & 0x03];
-        else {
-                if (lowpan_fetch_skb_u8(skb, &(hdr.hop_limit)))
-                        goto drop;
-        }
-
-        /* Extract SAM to the tmp variable */
-        tmp = ((iphc1 & LOWPAN_IPHC_SAM) >> LOWPAN_IPHC_SAM_BIT) & 0x03;
-
-        if (iphc1 & LOWPAN_IPHC_SAC) {
-                /* Source address context based uncompression */
-                pr_debug("SAC bit is set. Handle context based source address.\n");
-                err = lowpan_uncompress_context_based_src_addr(
-                                skb, &hdr.saddr, tmp);
-        } else {
-                /* Source address uncompression */
-                pr_debug("source address stateless compression\n");
-                err = lowpan_uncompress_addr(skb, &hdr.saddr, tmp, _saddr);
-        }
-
-        /* Check on error of previous branch */
-        if (err)
-                goto drop;
-
-        /* Extract DAM to the tmp variable */
-        tmp = ((iphc1 & LOWPAN_IPHC_DAM_11) >> LOWPAN_IPHC_DAM_BIT) & 0x03;
-
-        /* check for Multicast Compression */
-        if (iphc1 & LOWPAN_IPHC_M) {
-                if (iphc1 & LOWPAN_IPHC_DAC) {
-                        pr_debug("dest: context-based mcast compression\n");
-                        /* TODO: implement this */
-                } else {
-                        err = lowpan_uncompress_multicast_daddr(
-                                        skb, &hdr.daddr, tmp);
-                        if (err)
-                                goto drop;
-                }
-        } else {
-                pr_debug("dest: stateless compression\n");
-                err = lowpan_uncompress_addr(skb, &hdr.daddr, tmp, _daddr);
-                if (err)
-                        goto drop;
-        }
-
-        /* UDP data uncompression */
-        if (iphc0 & LOWPAN_IPHC_NH_C) {
-                struct udphdr uh;
-                struct sk_buff *new;
-                if (lowpan_uncompress_udp_header(skb, &uh))
-                        goto drop;
-
-                /*
-                 * replace the compressed UDP head by the uncompressed UDP
-                 * header
-                 */
-                new = skb_copy_expand(skb, sizeof(struct udphdr),
-                                      skb_tailroom(skb), GFP_ATOMIC);
-                kfree_skb(skb);
-
-                if (!new)
-                        return -ENOMEM;
-
-                skb = new;
-
-                skb_push(skb, sizeof(struct udphdr));
-                skb_copy_to_linear_data(skb, &uh, sizeof(struct udphdr));
-
-                lowpan_raw_dump_table(__func__, "raw UDP header dump",
-                                      (u8 *)&uh, sizeof(uh));
-
-                hdr.nexthdr = UIP_PROTO_UDP;
-        }
-
-        /* Not fragmented package */
-        hdr.payload_len = htons(skb->len);
-
-        pr_debug("skb headroom size = %d, data length = %d\n",
-                 skb_headroom(skb), skb->len);
-
-        pr_debug("IPv6 header dump:\n\tversion = %d\n\tlength  = %d\n\t"
-                 "nexthdr = 0x%02x\n\thop_lim = %d\n", hdr.version,
-                 ntohs(hdr.payload_len), hdr.nexthdr, hdr.hop_limit);
-
-        lowpan_raw_dump_table(__func__, "raw header dump", (u8 *)&hdr,
-                                                        sizeof(hdr));
-        return lowpan_skb_deliver(skb, &hdr);
+        return lowpan_process_data(skb, skb->dev, (u8 *)_saddr->hwaddr,
+                                _saddr->addr_type, IEEE802154_ADDR_LEN,
+                                (u8 *)_daddr->hwaddr, _daddr->addr_type,
+                                IEEE802154_ADDR_LEN, iphc0, iphc1,
+                                lowpan_give_skb_to_devices);
 
 unlock_and_drop:
         spin_unlock_bh(&flist_lock);
@@ -1316,7 +633,7 @@ 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);
 
-                lowpan_give_skb_to_devices(local_skb);
+                lowpan_give_skb_to_devices(local_skb, NULL);
 
                 kfree_skb(local_skb);
                 kfree_skb(skb);
@@ -1328,7 +645,7 @@ static int lowpan_rcv(struct sk_buff *skb, struct net_device *dev,
                         local_skb = skb_clone(skb, GFP_ATOMIC);
                         if (!local_skb)
                                 goto drop;
-                        lowpan_process_data(local_skb);
+                        process_data(local_skb);
 
                         kfree_skb(skb);
                         break;