diff options
| -rw-r--r-- | net/ieee802154/6lowpan.c | 78 |
1 files changed, 59 insertions, 19 deletions
diff --git a/net/ieee802154/6lowpan.c b/net/ieee802154/6lowpan.c index 632b3fdf46a4..9aea7ce8b83d 100644 --- a/net/ieee802154/6lowpan.c +++ b/net/ieee802154/6lowpan.c @@ -88,15 +88,6 @@ static const u8 lowpan_unc_llconf[] = {0x0f, 0x28, 0x22, 0x20}; */ static const u8 lowpan_unc_ctxconf[] = {0x00, 0x88, 0x82, 0x80}; -/* - * Uncompression of ctx-base - * 0 -> 0 bits from packet - * 1 -> 2 bytes from prefix - bunch of zeroes 5 from packet - * 2 -> 2 bytes from prefix - zeroes + 3 from packet - * 3 -> 2 bytes from prefix - infer 1 bytes from lladdr - */ -static const u8 lowpan_unc_mxconf[] = {0x0f, 0x25, 0x23, 0x21}; - /* Link local prefix */ static const u8 lowpan_llprefix[] = {0xfe, 0x80}; @@ -240,6 +231,63 @@ lowpan_uncompress_addr(struct sk_buff *skb, struct in6_addr *ipaddr, 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) { @@ -927,16 +975,8 @@ lowpan_process_data(struct sk_buff *skb) pr_debug("dest: context-based mcast compression\n"); /* TODO: implement this */ } else { - u8 prefix[] = {0xff, 0x02}; - - pr_debug("dest: non context-based mcast compression\n"); - if (0 < tmp && tmp < 3) { - if (lowpan_fetch_skb_u8(skb, &prefix[1])) - goto drop; - } - - err = lowpan_uncompress_addr(skb, &hdr.daddr, prefix, - lowpan_unc_mxconf[tmp], NULL); + err = lowpan_uncompress_multicast_daddr( + skb, &hdr.daddr, tmp); if (err) goto drop; } |