sbradclient

Setup utility for a certain BB in Japan.
Original repo: https://github.com/kruton/sofutobanku

Normal setup flow

1. ICMPv6 Router Solicitation
   1. Receive MTU information from router (i.e., 1500 bytes; see section 2.4.2.1.5 of FLETS)
2. IPv6 DHCP exchange (Internet)
   • Request:
     1. Client ID must be of the DUID-LL (Link Layer) type (see section 2.4.2.1.4 of FLETS)
        • Format is 00:03:00:01:<6-byte MAC address>
     2. Request should include Prefix Delegation (PD) (see section 2.4.2.1.2 of FLETS)
   • Response:
     1. Vendor-specific information (NTT):
        1. MAC address (option 201)
        2. Hikari Denwa telephone number (option 202)
        3. SIP domain (option 204)
        4. Route information (option 210; not needed?)
     2. Identity Assocation for Prefix Delegation (IA-PD)
        • Sends a /64 address (/56 PD prefix if Hikari Denwa is available or CROSS type)
        • A certain network interface must add an address like this:
          [NEXT] xxxx:xxxx:xxxx:xx00:1111:1111:1111:1111/64 (not on the interface it received the delegation from)
          [CROSS] xxxx:xxxx:xxxx:xx00:yy:yyyy:yy00:0 (yy:yyyy:yy is the hex format of tunnel local IPv4 address)
3. IPv6 RADIUS exchange (IPv4-over-IPv6 setup)
   • Access-Request (1) packet:
     1. RADIUS Shared Secret and Password is needed
     2. Contains a special IPv6 address as username
        • Format is
          [NEXT] xxxx:xxxx:xxxx:xx00:1111:1111:1111:1111
          [CROSS] xxxx:xxxx:xxxx:xx00
     3. Must contain Vendor Specific Attributes (VSA)
        • CPE MAC address (1)
        • CPE vendor name (2)
        • CPE product name (3)
        • CPE hardware version (4)
          NOTE: In CROSS type, CPE MAC address must be the LAN side MAC of HGW and all of VSA must be in the same AVP.
     4. CHAP authentication
        • Uses CHAP-Challenge (60) attribute
        • Password and secret are shared.
   • Access-Accept (2) packet:
     1. Contains Vendor Specific Attributes (VSA)
        • CPE WAN IPv4 address (204)
        • IPv6 gateway address (207)
     2. Other attributes don't appear to be useful
4. IPv4-over-IPv6 tunnel setup
   1. Use parameters discovered in IPv6 RADIUS exchange
   2. Must NOT have Tunnel Encapsulation Limit Option