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Is UDP-Lite checksum correct (IPv6) ?

0

the packet
00 50 56 c0 00 01 //dst mac
00 0c 29 fb 59 a8 //src mac
86 dd
60 00 00 00 //ipv6
00 28 //payload length
88 //next header UDP-Lite
80 //hop limit
20 01 00 00 00 00 00 00 00 00 00 00 00 00 00 01 //src ip
20 01 00 00 00 00 00 00 00 00 00 00 00 00 00 02 //dst ip
80 00 //src port
94 90 //dst port
00 08 //checksum coverage
aa b1 //checksum
61 62 //data
63 64 65 66 67 68 69 6a 6b 6c 6d 6e 6f 70 71 72
73 74 75 76 77 61 62 63 64 65 66 67 68 69
//end
when I open the packet with wireshark 1.6.0, the checksum is correct. But wireshark 1.6.8 tells me that the checksum is incorrect, it should be 0xaa89. Does payload length include IPv6 header length(40 bytes) when check UDP-Lite checksum?

asked 10 Jun '12, 09:26

Wolf%20Wong's gravatar image

Wolf Wong
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edited 10 Jun '12, 09:36

One Answer:

1

The checksum is correct. A bug was introduced in r40387, which was made to fix bug 6711. However, at the time, I didn't realize the slight difference in the pseudo header between UDP and UDP-Lite, as pointed out in RFC 3828. I have committed a change in r43187 to fix this and I scheduled it to be backported to 1.8.0.rc2, 1.6.9 and 1.4.14.

answered 10 Jun '12, 12:52

cmaynard's gravatar image

cmaynard ♦♦
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