dhcpcd-discuss

Re: [dhcpcd-discuss] dhcpcd.duid - timestamp being changed in solicit
From: Roger James roger@xxxxxxxxxxxxxxxxxxxxx
To: Roy Marples roy@xxxxxxxxxxxx
Sunday, 17 March 2019, 10:59




Just reached the same conclusion myself. I have been  using tcpdump and 
have just added the option to dump the undecoded link layer data as well as 
the decode.








 12 10:44:39.466951 c2:56:27:d4:a7:52 > b8:27:eb:cb:66:97, ethertype IPv6 
(0x86dd), length 182: (flowlabel 0x351c4, hlim 64, next-header UDP (17) 
payload length: 128) fe80::c056:27ff:fed4:a752.547 > 
fe80::ef44:891d:808e:b0da.546: [udp sum ok] dhcp6 reply (xid=b8d5e3 
(server-ID hwaddr type 1 c25627d4a752) (client-ID vid f0ef37dd7fa54bac) 
(opt_82) (rapid-commit) (DNS-server fda0:4d7f:afbb:4c2f::1) 
(reconfigure-accept) (IA_NA IAID:3955975831 T1:21600 T2:34560 (IA_ADDR 
fda0:4d7f:afbb:4c2f::798 pltime:4294967295 vltime:4294967295)))
      0x0000: 6003 51c4 0080 1140 fe80 0000 0000 0000
      0x0010: c056 27ff fed4 a752 fe80 0000 0000 0000
      0x0020: ef44 891d 808e b0da 0223 0222 0080 fa8f
      0x0030: 07b8 d5e3 0002 000a 0003 0001 c256 27d4
      0x0040: a752 0001 0012 0002 f0ef 37dd 7fa5 4bac
      0x0050: 94fa fb6c 08bb 09b8 0052 0004 0000 003c
      0x0060: 000e 0000 0017 0010 fda0 4d7f afbb 4c2f
      0x0070: 0000 0000 0000 0001 0014 0000 0003 0028
      0x0080: ebcb 6697 0000 5460 0000 8700 0005 0018
      0x0090: fda0 4d7f afbb 4c2f 0000 0000 0000 0798
      0x00a0: ffff ffff ffff ffff




The client id decode truncates the data but the data dump shows the full 
duid in the packet (offset 0x4c).








Argh!!!!!!








Roger