16-bit addr compression fix

This commit is contained in:
Joakim Eriksson 2011-03-06 22:34:16 +01:00
parent ca831a1553
commit 972c1992d2
2 changed files with 13 additions and 7 deletions

View file

@ -268,7 +268,7 @@ static uint8_t *hc06_ptr;
/* Uncompression of linklocal */
/* 0 -> 16 bytes from packet */
/* 1 -> 2 bytes from prefix - bunch of zeroes and 8 from packet */
/* 2 -> 2 bytes from prefix - zeroes + 2 from packet */
/* 2 -> 2 bytes from prefix - 0000::00ff:fe00:XXXX from packet */
/* 3 -> 2 bytes from prefix - infer 8 bytes from lladdr */
/* NOTE: => the uncompress function does change 0xf to 0x10 */
/* NOTE: 0x00 => no-autoconfig => unspecified */
@ -277,7 +277,7 @@ const uint8_t unc_llconf[] = {0x0f,0x28,0x22,0x20};
/* Uncompression of ctx-based */
/* 0 -> 0 bits from packet [unspecified / reserved] */
/* 1 -> 8 bytes from prefix - bunch of zeroes and 8 from packet */
/* 2 -> 8 bytes from prefix - zeroes + 2 from packet */
/* 2 -> 8 bytes from prefix - 0000::00ff:fe00:XXXX + 2 from packet */
/* 3 -> 8 bytes from prefix - infer 8 bytes from lladdr */
const uint8_t unc_ctxconf[] = {0x00,0x88,0x82,0x80};
@ -338,7 +338,7 @@ compress_addr_64(uint8_t bitpos, uip_ipaddr_t *ipaddr, uip_lladdr_t *lladdr)
if(uip_is_addr_mac_addr_based(ipaddr, lladdr)) {
return 3 << bitpos; /* 0-bits */
} else if(sicslowpan_is_iid_16_bit_compressable(ipaddr)) {
/* compress IID to 16 bits xxxx::XXXX */
/* compress IID to 16 bits xxxx::0000:00ff:fe00:XXXX */
memcpy(hc06_ptr, &ipaddr->u16[7], 2);
hc06_ptr += 2;
return 2 << bitpos; /* 16-bits */
@ -377,6 +377,11 @@ uncompress_addr(uip_ipaddr_t *ipaddr, uint8_t const prefix[],
}
if(postcount > 0) {
memcpy(&ipaddr->u8[16 - postcount], hc06_ptr, postcount);
if(postcount == 2 && prefcount < 11) {
/* 16 bits uncompression => 0000:00ff:fe00:XXXX */
ipaddr->u8[11] = 0xff;
ipaddr->u8[12] = 0xfe;
}
hc06_ptr += postcount;
} else if (prefcount > 0) {
/* no IID based configuration if no prefix and no data => unspec */

View file

@ -233,13 +233,14 @@ struct sicslowpan_addr_context {
* \brief check whether we can compress the IID in
* address 'a' to 16 bits.
* This is used for unicast addresses only, and is true
* if first 49 bits of IID are 0
* the address is on the format ::0000:00ff:fe00:XXXX
*/
#define sicslowpan_is_iid_16_bit_compressable(a) \
((((a)->u16[4]) == 0) && \
(((a)->u16[5]) == 0) && \
(((a)->u16[6]) == 0) && \
((((a)->u8[14]) & 0x80) == 0))
(((a)->u8[10]) == 0) && \
(((a)->u8[11]) == 0xff) && \
(((a)->u8[12]) == 0xfe) && \
(((a)->u8[13]) == 0))
/**
* \brief check whether the 9-bit group-id of the