From eab560e58208730ec47e1e0461b8db1049d5d176 Mon Sep 17 00:00:00 2001 From: Alexander Aring Date: Wed, 15 Jun 2016 21:20:27 +0200 Subject: 6lowpan: add support for 802.15.4 short addr handling This patch adds necessary handling for use the short address for 802.15.4 6lowpan. It contains support for IPHC address compression and new matching algorithmn to decide which link layer address will be used for 802.15.4 frame. Reviewed-by: Stefan Schmidt Signed-off-by: Alexander Aring Signed-off-by: David S. Miller --- net/6lowpan/iphc.c | 167 +++++++++++++++++++++++++++++++++++++++++++---------- 1 file changed, 138 insertions(+), 29 deletions(-) (limited to 'net/6lowpan') diff --git a/net/6lowpan/iphc.c b/net/6lowpan/iphc.c index 8501dd532fe1..79f1fa22509a 100644 --- a/net/6lowpan/iphc.c +++ b/net/6lowpan/iphc.c @@ -761,22 +761,75 @@ static const u8 lowpan_iphc_dam_to_sam_value[] = { [LOWPAN_IPHC_DAM_11] = LOWPAN_IPHC_SAM_11, }; -static u8 lowpan_compress_ctx_addr(u8 **hc_ptr, const struct in6_addr *ipaddr, +static inline bool +lowpan_iphc_compress_ctx_802154_lladdr(const struct in6_addr *ipaddr, + const struct lowpan_iphc_ctx *ctx, + const void *lladdr) +{ + const struct ieee802154_addr *addr = lladdr; + unsigned char extended_addr[EUI64_ADDR_LEN]; + bool lladdr_compress = false; + struct in6_addr tmp = {}; + + switch (addr->mode) { + case IEEE802154_ADDR_LONG: + ieee802154_le64_to_be64(&extended_addr, &addr->extended_addr); + /* check for SAM/DAM = 11 */ + memcpy(&tmp.s6_addr[8], &extended_addr, EUI64_ADDR_LEN); + /* second bit-flip (Universe/Local) is done according RFC2464 */ + tmp.s6_addr[8] ^= 0x02; + /* context information are always used */ + ipv6_addr_prefix_copy(&tmp, &ctx->pfx, ctx->plen); + if (ipv6_addr_equal(&tmp, ipaddr)) + lladdr_compress = true; + break; + case IEEE802154_ADDR_SHORT: + tmp.s6_addr[11] = 0xFF; + tmp.s6_addr[12] = 0xFE; + ieee802154_le16_to_be16(&tmp.s6_addr16[7], + &addr->short_addr); + /* context information are always used */ + ipv6_addr_prefix_copy(&tmp, &ctx->pfx, ctx->plen); + if (ipv6_addr_equal(&tmp, ipaddr)) + lladdr_compress = true; + break; + default: + /* should never handled and filtered by 802154 6lowpan */ + WARN_ON_ONCE(1); + break; + } + + return lladdr_compress; +} + +static u8 lowpan_compress_ctx_addr(u8 **hc_ptr, const struct net_device *dev, + const struct in6_addr *ipaddr, const struct lowpan_iphc_ctx *ctx, const unsigned char *lladdr, bool sam) { struct in6_addr tmp = {}; u8 dam; - /* check for SAM/DAM = 11 */ - memcpy(&tmp.s6_addr[8], lladdr, 8); - /* second bit-flip (Universe/Local) is done according RFC2464 */ - tmp.s6_addr[8] ^= 0x02; - /* context information are always used */ - ipv6_addr_prefix_copy(&tmp, &ctx->pfx, ctx->plen); - if (ipv6_addr_equal(&tmp, ipaddr)) { - dam = LOWPAN_IPHC_DAM_11; - goto out; + switch (lowpan_dev(dev)->lltype) { + case LOWPAN_LLTYPE_IEEE802154: + if (lowpan_iphc_compress_ctx_802154_lladdr(ipaddr, ctx, + lladdr)) { + dam = LOWPAN_IPHC_DAM_11; + goto out; + } + break; + default: + /* check for SAM/DAM = 11 */ + memcpy(&tmp.s6_addr[8], lladdr, EUI64_ADDR_LEN); + /* second bit-flip (Universe/Local) is done according RFC2464 */ + tmp.s6_addr[8] ^= 0x02; + /* context information are always used */ + ipv6_addr_prefix_copy(&tmp, &ctx->pfx, ctx->plen); + if (ipv6_addr_equal(&tmp, ipaddr)) { + dam = LOWPAN_IPHC_DAM_11; + goto out; + } + break; } memset(&tmp, 0, sizeof(tmp)); @@ -813,28 +866,85 @@ out: return dam; } -static u8 lowpan_compress_addr_64(u8 **hc_ptr, const struct in6_addr *ipaddr, +static inline bool +lowpan_iphc_compress_802154_lladdr(const struct in6_addr *ipaddr, + const void *lladdr) +{ + const struct ieee802154_addr *addr = lladdr; + unsigned char extended_addr[EUI64_ADDR_LEN]; + bool lladdr_compress = false; + struct in6_addr tmp = {}; + + switch (addr->mode) { + case IEEE802154_ADDR_LONG: + ieee802154_le64_to_be64(&extended_addr, &addr->extended_addr); + if (is_addr_mac_addr_based(ipaddr, extended_addr)) + lladdr_compress = true; + break; + case IEEE802154_ADDR_SHORT: + /* fe:80::ff:fe00:XXXX + * \__/ + * short_addr + * + * Universe/Local bit is zero. + */ + tmp.s6_addr[0] = 0xFE; + tmp.s6_addr[1] = 0x80; + tmp.s6_addr[11] = 0xFF; + tmp.s6_addr[12] = 0xFE; + ieee802154_le16_to_be16(&tmp.s6_addr16[7], + &addr->short_addr); + if (ipv6_addr_equal(&tmp, ipaddr)) + lladdr_compress = true; + break; + default: + /* should never handled and filtered by 802154 6lowpan */ + WARN_ON_ONCE(1); + break; + } + + return lladdr_compress; +} + +static u8 lowpan_compress_addr_64(u8 **hc_ptr, const struct net_device *dev, + const struct in6_addr *ipaddr, const unsigned char *lladdr, bool sam) { - u8 dam = LOWPAN_IPHC_DAM_00; + u8 dam = LOWPAN_IPHC_DAM_01; - if (is_addr_mac_addr_based(ipaddr, lladdr)) { - dam = LOWPAN_IPHC_DAM_11; /* 0-bits */ - pr_debug("address compression 0 bits\n"); - } else if (lowpan_is_iid_16_bit_compressable(ipaddr)) { + switch (lowpan_dev(dev)->lltype) { + case LOWPAN_LLTYPE_IEEE802154: + if (lowpan_iphc_compress_802154_lladdr(ipaddr, lladdr)) { + dam = LOWPAN_IPHC_DAM_11; /* 0-bits */ + pr_debug("address compression 0 bits\n"); + goto out; + } + break; + default: + if (is_addr_mac_addr_based(ipaddr, lladdr)) { + dam = LOWPAN_IPHC_DAM_11; /* 0-bits */ + pr_debug("address compression 0 bits\n"); + goto out; + } + break; + } + + if (lowpan_is_iid_16_bit_compressable(ipaddr)) { /* compress IID to 16 bits xxxx::XXXX */ lowpan_push_hc_data(hc_ptr, &ipaddr->s6_addr16[7], 2); dam = LOWPAN_IPHC_DAM_10; /* 16-bits */ raw_dump_inline(NULL, "Compressed ipv6 addr is (16 bits)", *hc_ptr - 2, 2); - } else { - /* do not compress IID => xxxx::IID */ - lowpan_push_hc_data(hc_ptr, &ipaddr->s6_addr16[4], 8); - dam = LOWPAN_IPHC_DAM_01; /* 64-bits */ - raw_dump_inline(NULL, "Compressed ipv6 addr is (64 bits)", - *hc_ptr - 8, 8); + goto out; } + /* do not compress IID => xxxx::IID */ + lowpan_push_hc_data(hc_ptr, &ipaddr->s6_addr16[4], 8); + raw_dump_inline(NULL, "Compressed ipv6 addr is (64 bits)", + *hc_ptr - 8, 8); + +out: + if (sam) return lowpan_iphc_dam_to_sam_value[dam]; else @@ -1013,9 +1123,6 @@ int lowpan_header_compress(struct sk_buff *skb, const struct net_device *dev, iphc0 = LOWPAN_DISPATCH_IPHC; iphc1 = 0; - raw_dump_inline(__func__, "saddr", saddr, EUI64_ADDR_LEN); - raw_dump_inline(__func__, "daddr", daddr, EUI64_ADDR_LEN); - raw_dump_table(__func__, "sending raw skb network uncompressed packet", skb->data, skb->len); @@ -1088,14 +1195,15 @@ int lowpan_header_compress(struct sk_buff *skb, const struct net_device *dev, iphc1 |= LOWPAN_IPHC_SAC; } else { if (sci) { - iphc1 |= lowpan_compress_ctx_addr(&hc_ptr, &hdr->saddr, + iphc1 |= lowpan_compress_ctx_addr(&hc_ptr, dev, + &hdr->saddr, &sci_entry, saddr, true); iphc1 |= LOWPAN_IPHC_SAC; } else { if (ipv6_saddr_type & IPV6_ADDR_LINKLOCAL && lowpan_is_linklocal_zero_padded(hdr->saddr)) { - iphc1 |= lowpan_compress_addr_64(&hc_ptr, + iphc1 |= lowpan_compress_addr_64(&hc_ptr, dev, &hdr->saddr, saddr, true); pr_debug("source address unicast link-local %pI6c iphc1 0x%02x\n", @@ -1123,14 +1231,15 @@ int lowpan_header_compress(struct sk_buff *skb, const struct net_device *dev, } } else { if (dci) { - iphc1 |= lowpan_compress_ctx_addr(&hc_ptr, &hdr->daddr, + iphc1 |= lowpan_compress_ctx_addr(&hc_ptr, dev, + &hdr->daddr, &dci_entry, daddr, false); iphc1 |= LOWPAN_IPHC_DAC; } else { if (ipv6_daddr_type & IPV6_ADDR_LINKLOCAL && lowpan_is_linklocal_zero_padded(hdr->daddr)) { - iphc1 |= lowpan_compress_addr_64(&hc_ptr, + iphc1 |= lowpan_compress_addr_64(&hc_ptr, dev, &hdr->daddr, daddr, false); pr_debug("dest address unicast link-local %pI6c iphc1 0x%02x\n", -- cgit v1.2.3-59-g8ed1b