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Significant edit pass over ICMPv6 code.

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Matti, more per mail.
This commit is contained in:
Robin Sommer 2011-01-25 17:54:20 -08:00
parent cb64bb6874
commit 50181edd84
10 changed files with 424 additions and 719 deletions
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39
src/net_util.cc
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@ -86,14 +86,8 @@ int udp_checksum(const struct ip* ip, const struct udphdr* up, int len)
#ifdef BROv6
int udp6_checksum(const struct ip6_hdr* ip6, const struct udphdr* up, int len)
{
/**From RFC for udp4 (same for udp6, except for different pseudoheader which is same as for icmp6)
Computed as the 16-bit one's complement of the one's complement sum of a
pseudo header of information from the IP header, the UDP header, and the
data, padded as needed with zero bytes at the end to make a multiple of
two bytes. If the checksum is cleared to zero, then checksuming is
disabled. If the computed checksum is zero, then this field must be set
to 0xFFFF.
**/
// UDP over IPv6 uses the same checksum function as over IPv4 but a
// different pseuod-header over which it is computed.
uint32 sum;
if ( len % 2 == 1 )
@ -108,23 +102,18 @@ int udp6_checksum(const struct ip6_hdr* ip6, const struct udphdr* up, int len)
uint32 l = htonl(len);
sum = ones_complement_checksum((void*) &l, 4, sum);
uint32 addl_pseudo = htons(IPPROTO_UDP);
sum = ones_complement_checksum((void*) &addl_pseudo, 4, sum);
sum = ones_complement_checksum((void*) up, len, sum);
//printf("checksum, calculated for UDP6: %d\n",sum);
return sum;
}
int icmp6_checksum(const struct icmp* icmpp, const struct ip6_hdr* ip6, int len)
{
/**From RFC
Checksum that covers the ICMPv6 message. This field contains the 16-bit one's
complement of the one's complement sum of the entire ICMPv6 message starting
with the ICMPv6 message type field, prepended with a pseudo-header of IPv6
header fields.
**/
// ICMP6 uses the same checksum function as over ICMP4 but a different
// pseuod-header over which it is computed.
uint32 sum;
if ( len % 2 == 1 )
@ -133,19 +122,17 @@ int icmp6_checksum(const struct icmp* icmpp, const struct ip6_hdr* ip6, int len)
else
sum = 0;
//pseudoheader as in udp6 above
// Pseudo-header as for UDP over IPv6 above.
sum = ones_complement_checksum((void*) ip6->ip6_src.s6_addr, 16, sum);
sum = ones_complement_checksum((void*) ip6->ip6_dst.s6_addr, 16, sum);
uint32 l = htonl(len);
sum = ones_complement_checksum((void*) &l, 4, sum);
uint32 addl_pseudo = htons(IPPROTO_ICMPV6);
sum = ones_complement_checksum((void*) &addl_pseudo, 4, sum);
//pseudoheader complete
sum = ones_complement_checksum((void*) icmpp, len, sum);
//printf("checksum, calculated for ICMP6: %d\n",sum);
return sum;
}
@ -153,12 +140,6 @@ int icmp6_checksum(const struct icmp* icmpp, const struct ip6_hdr* ip6, int len)
int icmp_checksum(const struct icmp* icmpp, int len)
{
/**From RFC
Checksum that covers the ICMP message. This is the 16-bit one's
complement of the one's complement sum of the ICMP message starting
with the Type field. The checksum field should be cleared to zero
before generating the checksum.
**/
uint32 sum;
if ( len % 2 == 1 )
// Add in pad byte.
@ -168,15 +149,9 @@ int icmp_checksum(const struct icmp* icmpp, int len)
sum = ones_complement_checksum((void*) icmpp, len, sum);
//printf("checksum, calculated for ICMP4: %d\n",sum);
return sum;
}
#define CLASS_A 0x00000000
#define CLASS_B 0x80000000
#define CLASS_C 0xc0000000