Return-Path: From: Jukka Rissanen To: linux-bluetooth@vger.kernel.org Subject: [PATCH v10 1/5] 6lowpan: Moving generic compression code into 6lowpan_iphc.c Date: Wed, 11 Dec 2013 17:05:34 +0200 Message-Id: <1386774338-2093-2-git-send-email-jukka.rissanen@linux.intel.com> In-Reply-To: <1386774338-2093-1-git-send-email-jukka.rissanen@linux.intel.com> References: <1386774338-2093-1-git-send-email-jukka.rissanen@linux.intel.com> Sender: linux-bluetooth-owner@vger.kernel.org List-ID: 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 Acked-by: Alexander Aring --- net/ieee802154/6lowpan.c | 753 ++------------------------------------- net/ieee802154/6lowpan.h | 32 ++ net/ieee802154/6lowpan_iphc.c | 807 ++++++++++++++++++++++++++++++++++++++++++ net/ieee802154/Makefile | 2 +- 4 files changed, 875 insertions(+), 719 deletions(-) create mode 100644 net/ieee802154/6lowpan_iphc.c diff --git a/net/ieee802154/6lowpan.c b/net/ieee802154/6lowpan.c index 459e200..53d0bd5 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; diff --git a/net/ieee802154/6lowpan.h b/net/ieee802154/6lowpan.h index 2869c05..535606d 100644 --- a/net/ieee802154/6lowpan.h +++ b/net/ieee802154/6lowpan.h @@ -232,6 +232,28 @@ dest = 16 bit inline */ #define LOWPAN_NHC_UDP_CS_P_11 0xF3 /* source & dest = 0xF0B + 4bit inline */ +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 inline bool lowpan_fetch_skb(struct sk_buff *skb, void *data, const unsigned int len) { @@ -244,4 +266,14 @@ static inline bool lowpan_fetch_skb(struct sk_buff *skb, return false; } +typedef int (*skb_delivery_cb)(struct sk_buff *skb, struct net_device *dev); + +int lowpan_process_data(struct sk_buff *skb, struct net_device *dev, + const u8 *saddr, const u8 saddr_type, const u8 saddr_len, + const u8 *daddr, const u8 daddr_type, const u8 daddr_len, + u8 iphc0, u8 iphc1, skb_delivery_cb skb_deliver); +int lowpan_header_compress(struct sk_buff *skb, struct net_device *dev, + unsigned short type, const void *_daddr, + const void *_saddr, unsigned int len); + #endif /* __6LOWPAN_H__ */ diff --git a/net/ieee802154/6lowpan_iphc.c b/net/ieee802154/6lowpan_iphc.c new file mode 100644 index 0000000..57c0b7a --- /dev/null +++ b/net/ieee802154/6lowpan_iphc.c @@ -0,0 +1,807 @@ +/* + * Copyright 2011, Siemens AG + * written by Alexander Smirnov + */ + +/* + * Based on patches from Jon Smirl + * Copyright (c) 2011 Jon Smirl + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 + * as published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License along + * with this program; if not, write to the Free Software Foundation, Inc., + * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. + */ + +/* Jon's code is based on 6lowpan implementation for Contiki which is: + * Copyright (c) 2008, Swedish Institute of Computer Science. + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. Neither the name of the Institute nor the names of its contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + */ + +#include +#include +#include +#include +#include + +#include "6lowpan.h" + +/* print data in line */ +static inline void raw_dump_inline(const char *caller, char *msg, + unsigned char *buf, int len) +{ + if (msg) + pr_debug("%s():%s: ", caller, msg); + print_hex_dump_debug("", DUMP_PREFIX_NONE, + 16, 1, buf, len, false); +} + +/* + * print data in a table format: + * + * addr: xx xx xx xx xx xx + * addr: xx xx xx xx xx xx + * ... + */ +static inline void raw_dump_table(const char *caller, char *msg, + unsigned char *buf, int len) +{ + if (msg) + pr_debug("%s():%s:\n", caller, msg); + print_hex_dump_debug("\t", DUMP_PREFIX_OFFSET, + 16, 1, buf, len, false); +} + +/* + * Uncompress address function for source and + * destination address(non-multicast). + * + * address_mode is sam value or dam value. + */ +static int uncompress_addr(struct sk_buff *skb, + struct in6_addr *ipaddr, const u8 address_mode, + const u8 *lladdr, const u8 addr_type, + const u8 addr_len) +{ + 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 (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, 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(*((u16 *)lladdr)); + 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; + } + + raw_dump_inline(NULL, "Reconstructed ipv6 addr is", + ipaddr->s6_addr, 16); + + return 0; +} + +/* + * Uncompress address function for source context + * based address(non-multicast). + */ +static int 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; + } + + raw_dump_inline(NULL, + "Reconstructed context based ipv6 src addr is", + ipaddr->s6_addr, 16); + + return 0; +} + +static int skb_deliver(struct sk_buff *skb, struct ipv6hdr *hdr, + struct net_device *dev, skb_delivery_cb deliver_skb) +{ + struct sk_buff *new; + int stat; + + 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_reset_network_header(new); + skb_copy_to_linear_data(new, hdr, sizeof(struct ipv6hdr)); + + new->protocol = htons(ETH_P_IPV6); + new->pkt_type = PACKET_HOST; + new->dev = dev; + + raw_dump_table(__func__, "raw skb data dump before receiving", + new->data, new->len); + + stat = deliver_skb(new, dev); + + kfree_skb(new); + + return stat; +} + +/* 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; + } + + raw_dump_inline(NULL, "Reconstructed ipv6 multicast addr is", + ipaddr->s6_addr, 16); + + return 0; +} + +static int +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; + break; + } + + 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; +} + +/* TTL uncompression values */ +static const u8 lowpan_ttl_values[] = { 0, 1, 64, 255 }; + +int lowpan_process_data(struct sk_buff *skb, struct net_device *dev, + const u8 *saddr, const u8 saddr_type, const u8 saddr_len, + const u8 *daddr, const u8 daddr_type, const u8 daddr_len, + u8 iphc0, u8 iphc1, skb_delivery_cb deliver_skb) +{ + struct ipv6hdr hdr = {}; + u8 tmp, num_context = 0; + int err; + + raw_dump_table(__func__, "raw skb data dump uncompressed", + skb->data, skb->len); + + /* 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 = uncompress_context_based_src_addr( + skb, &hdr.saddr, tmp); + } else { + /* Source address uncompression */ + pr_debug("source address stateless compression\n"); + err = uncompress_addr(skb, &hdr.saddr, tmp, saddr, + saddr_type, saddr_len); + } + + /* 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 { + err = uncompress_addr(skb, &hdr.daddr, tmp, daddr, + daddr_type, daddr_len); + pr_debug("dest: stateless compression mode %d dest %pI6c\n", + tmp, &hdr.daddr); + if (err) + goto drop; + } + + /* UDP data uncompression */ + if (iphc0 & LOWPAN_IPHC_NH_C) { + struct udphdr uh; + struct sk_buff *new; + if (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_reset_transport_header(skb); + skb_copy_to_linear_data(skb, &uh, sizeof(struct udphdr)); + + raw_dump_table(__func__, "raw UDP header dump", + (u8 *)&uh, sizeof(uh)); + + hdr.nexthdr = UIP_PROTO_UDP; + } + + 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\tdest = %pI6c\n", + hdr.version, ntohs(hdr.payload_len), hdr.nexthdr, + hdr.hop_limit, &hdr.daddr); + + raw_dump_table(__func__, "raw header dump", (u8 *)&hdr, + sizeof(hdr)); + + return skb_deliver(skb, &hdr, dev, deliver_skb); + +drop: + kfree_skb(skb); + return -EINVAL; +} +EXPORT_SYMBOL_GPL(lowpan_process_data); + +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 */ + pr_debug("address compression 0 bits\n"); + } 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 */ + raw_dump_inline(NULL, "Compressed ipv6 addr is (16 bits)", + *hc06_ptr - 2, 2); + } else { + /* do not compress IID => xxxx::IID */ + memcpy(*hc06_ptr, &ipaddr->s6_addr16[4], 8); + *hc06_ptr += 8; + val = 1; /* 64-bits */ + raw_dump_inline(NULL, "Compressed ipv6 addr is (64 bits)", + *hc06_ptr - 8, 8); + } + + return rol8(val, shift); +} + +static void 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)); +} + +int lowpan_header_compress(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; + u8 head[100] = {}; + + if (type != ETH_P_IPV6) + return -EINVAL; + + 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\tdest = %pI6c\n", + hdr->version, ntohs(hdr->payload_len), hdr->nexthdr, + hdr->hop_limit, &hdr->daddr); + + raw_dump_table(__func__, "raw skb network header dump", + skb_network_header(skb), sizeof(struct ipv6hdr)); + + /* + * 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 */ + + raw_dump_inline(__func__, "saddr", + (unsigned char *)_saddr, IEEE802154_ADDR_LEN); + raw_dump_inline(__func__, "daddr", + (unsigned char *)_daddr, IEEE802154_ADDR_LEN); + + raw_dump_table(__func__, + "sending raw skb network uncompressed packet", + skb->data, skb->len); + + /* + * 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)) { + iphc1 |= lowpan_compress_addr_64(&hc06_ptr, + LOWPAN_IPHC_SAM_BIT, &hdr->saddr, _saddr); + pr_debug("source address unicast link-local %pI6c " + "iphc1 0x%02x\n", &hdr->saddr, iphc1); + } 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)) { + iphc1 |= lowpan_compress_addr_64(&hc06_ptr, + LOWPAN_IPHC_DAM_BIT, &hdr->daddr, _daddr); + pr_debug("dest address unicast link-local %pI6c " + "iphc1 0x%02x\n", &hdr->daddr, iphc1); + } else { + pr_debug("dest address unicast %pI6c\n", &hdr->daddr); + memcpy(hc06_ptr, &hdr->daddr.s6_addr16[0], 16); + hc06_ptr += 16; + } + } + + /* UDP header compression */ + if (hdr->nexthdr == UIP_PROTO_UDP) + 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); + + pr_debug("header len %d skb %u\n", (int)(hc06_ptr - head), skb->len); + + raw_dump_table(__func__, "raw skb data dump compressed", + skb->data, skb->len); + return 0; +} +EXPORT_SYMBOL_GPL(lowpan_header_compress); diff --git a/net/ieee802154/Makefile b/net/ieee802154/Makefile index d7716d6..951a83e 100644 --- a/net/ieee802154/Makefile +++ b/net/ieee802154/Makefile @@ -1,5 +1,5 @@ obj-$(CONFIG_IEEE802154) += ieee802154.o af_802154.o -obj-$(CONFIG_IEEE802154_6LOWPAN) += 6lowpan.o +obj-$(CONFIG_IEEE802154_6LOWPAN) += 6lowpan.o 6lowpan_iphc.o ieee802154-y := netlink.o nl-mac.o nl-phy.o nl_policy.o wpan-class.o af_802154-y := af_ieee802154.o raw.o dgram.o -- 1.8.3.1