0

My request is to include option 17 sub-options 11, 12 and 13 in DHCPv6 solicit/request and I configured the same in dhclient6.conf on my Ubuntu as below.

send dhcp6.vendor-opts 00:00:0d:e9:00:0b:00:06:42:44:56:45:52:30:00:0c:00:03:6c:61:6e:00:0d:00:06:76:61:61:75:61:39;

From packet trace I can see option 17 in solicit/request but sub-options are not proper and I guess not encapsulated.

Output snippet from tshark:

Vendor-specific Information
    Option: Vendor-specific Information (17)
    Length: 31
    Value: 00000de9000b0006424456455230000c00036c616e000d00...
    Enterprise ID: The Broadband Forum (3561)
    option
        Option code: 11
        Option length: 6
        Option data: 424456455230
    option
        Option code: 12
        Option length: 3
        Option data: 6c616e
    option
        Option code: 13
        Option length: 6
        Option data: 766161756139

Can someone please help me on how to include sub-options in a correct format.

What I tried so far:

  1. Went through the RFC and configured as per the format by including option_code and option_len but got malformed packet.
  2. Referred similar type of question and configured option-17 sub-option 2 which is absolutely fine but problem occurs with sub-options 11, 12 and 13.

Any help would be appreciated.

Community
  • 1
kottesvaran m
  • 1
  • 1
  • Still looking for some assistance on the above question. Any help or leads would be appreciated.. – kottesvaran m Jan 06 '21 at 16:51
  • In your tshark damp everything is fine. But you have a mistake in dhcp6.vendor-opts line. You set option 12 twice. Replace 00:0c:00:06 with 00:0d:00:06. – Hedgehog Jan 12 '21 at 14:49
  • @Hedgehog Sorry, typo error and I edited the same. Below same device identity in DHCPv4 option 125 sub-option 1, 2 and 3 which looks fine whereas IPv6 DHCPv6 option 17 sub-option 11, 12 and 13 not. Did tshark is not parse/dissect those fields in v6 vendor opts? ----------------------------------------------------- Option: (125) V-I Vendor-specific Information Length: 26 Enterprise: The Broadband Forum (3561) Length: 21 Option 125 Suboption: (1) DeviceManufacturerOUI Length: 6 DeviceManufacturerOUI: 00:00:3a – kottesvaran m Jan 13 '21 at 21:32
  • I did not get your update. Your question was about DHCP IPv6. Tshark shows the values correctly. "BDVER0" and "lan" and "vaaua9" – Hedgehog Jan 14 '21 at 15:43
  • @Hedgehog First of all thank you for the response. I am trying to configure device identity option for both v4 and v6 (IPv4 is successful). If you see my previous comment IPv4 DHCP option 125 shows "Suboption (1) DeviceManufacturerOUI Length: 6 DeviceManufacturerOUI: 00:00:3c" on tshark and I am expecting similar for IPv6 option 17 (like "Suboption (11) DeviceManufacturerOUI Length: 6 DeviceManufacturerOUI: 00:00:3c"), but sub-options shows as option (plz see tshark dump on question) and no description like v4. Is there any limitation on tshark to parse v6 vendor opts ? – kottesvaran m Jan 15 '21 at 00:24
  • So the issue is only that tshark does not show sub-options names? From what I see in your DHCv6 config and tshark output the option 17 is correctly configured. I don't know if tshark supports naming for DHCPv6 option 17 especially for 3561. You may want to collect dump and open it with wireshark to see the names. Or you can try to see DHCPv6 server logs. – Hedgehog Jan 15 '21 at 14:24
  • @Hedgehog Thank you for you confirmation on DHCPv6 config. Wireshark also have the same result, no names, but I am clear now that the config is correct. – kottesvaran m Jan 17 '21 at 17:31

0 Answers0