6lowpan: put mcast compression in an own function

This patch moves the mcast compression algorithmn to an own function
like all other compression/decompression methods in iphc.

Signed-off-by: Alexander Aring <alex.aring@gmail.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
This commit is contained in:
Alexander Aring 2015-10-20 08:31:26 +02:00 committed by Marcel Holtmann
parent b5af9bdbfe
commit 09bf420f10
1 changed files with 32 additions and 27 deletions

View File

@ -708,6 +708,37 @@ static u8 lowpan_iphc_tf_compress(u8 **hc_ptr, const struct ipv6hdr *hdr)
return val;
}
static u8 lowpan_iphc_mcast_addr_compress(u8 **hc_ptr,
const struct in6_addr *ipaddr)
{
u8 val;
if (lowpan_is_mcast_addr_compressable8(ipaddr)) {
pr_debug("compressed to 1 octet\n");
/* use last byte */
lowpan_push_hc_data(hc_ptr, &ipaddr->s6_addr[15], 1);
val = LOWPAN_IPHC_DAM_11;
} else if (lowpan_is_mcast_addr_compressable32(ipaddr)) {
pr_debug("compressed to 4 octets\n");
/* second byte + the last three */
lowpan_push_hc_data(hc_ptr, &ipaddr->s6_addr[1], 1);
lowpan_push_hc_data(hc_ptr, &ipaddr->s6_addr[13], 3);
val = LOWPAN_IPHC_DAM_10;
} else if (lowpan_is_mcast_addr_compressable48(ipaddr)) {
pr_debug("compressed to 6 octets\n");
/* second byte + the last five */
lowpan_push_hc_data(hc_ptr, &ipaddr->s6_addr[1], 1);
lowpan_push_hc_data(hc_ptr, &ipaddr->s6_addr[11], 5);
val = LOWPAN_IPHC_DAM_01;
} else {
pr_debug("using full address\n");
lowpan_push_hc_data(hc_ptr, ipaddr->s6_addr, 16);
val = LOWPAN_IPHC_DAM_00;
}
return val;
}
int lowpan_header_compress(struct sk_buff *skb, const struct net_device *dev,
const void *daddr, const void *saddr)
{
@ -804,33 +835,7 @@ int lowpan_header_compress(struct sk_buff *skb, const struct net_device *dev,
if (addr_type & IPV6_ADDR_MULTICAST) {
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 */
lowpan_push_hc_data(&hc_ptr,
&hdr->daddr.s6_addr[15], 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 */
lowpan_push_hc_data(&hc_ptr,
&hdr->daddr.s6_addr[1], 1);
lowpan_push_hc_data(&hc_ptr,
&hdr->daddr.s6_addr[13], 3);
} 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 */
lowpan_push_hc_data(&hc_ptr,
&hdr->daddr.s6_addr[1], 1);
lowpan_push_hc_data(&hc_ptr,
&hdr->daddr.s6_addr[11], 5);
} else {
pr_debug("using full address\n");
iphc1 |= LOWPAN_IPHC_DAM_00;
lowpan_push_hc_data(&hc_ptr, hdr->daddr.s6_addr, 16);
}
iphc1 |= lowpan_iphc_mcast_addr_compress(&hc_ptr, &hdr->daddr);
} else {
if (addr_type & IPV6_ADDR_LINKLOCAL) {
/* TODO: context lookup */