MobileIP (RFC3012)

[joshua1909]

Hi,

I've been looking into some labbed mobile communication. It's a HMAC-MD5 made up of the following:
hmac_md5(data, datalen, Key, KeyLength, authenticator)

I've never looked into building a custom hash format. Would appreciate any tips or pointers?

Code:

where the Type, Length, Subtype, and SPI are as shown in section 5.
  The resulting function call, as described in [5], would be:

      hmac_md5(data, datalen, Key, KeyLength, authenticator);

  Each mobile node MUST support the ability to produce the
  authenticator by using HMAC-MD5 as shown.  Just as with Mobile IP,
  this default algorithm MUST be able to be configured for selection at
  any arbitrary 32-bit SPI outside of the SPIs in the reserved range
  0-255.

Code:

      0                  1                  2                  3
      0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |    Type      |    Subtype    |            Length            |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                              SPI                              |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                        Authenticator ...
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

      Figure 3: The Generalized Mobile IP Authentication Extension

      Type            36 (not skippable) (see [8])

      Subtype        a number assigned to identify the kind of
                      endpoints or characteristics of the particular
                      authentication strategy

      Length          4 plus the number of bytes in the Authenticator;
                      MUST be at least 20.

      SPI            Security Parameters Index

      Authenticator  The variable length Authenticator field

Cheers,
Josh

[joshua1909]

If anyone is willing to take this on, I am happy to pay to get this implemented.