RFC 2245 (rfc2245) - Page 2 of 5

Anonymous SASL Mechanism

RFC 2245                Anonymous SASL Mechanism           November 1997


   A server which permits anonymous access will announce support for the
   ANONYMOUS mechanism, and allow anyone to log in using that mechanism,
   usually with restricted access.

   The formal grammar for the client message using Augmented BNF [ABNF]
   follows.

   message         = [email / token]

   TCHAR           = %x20-3F / %x41-7E
                     ;; any printable US-ASCII character except '@'

   email           = addr-spec
                     ;; as defined in [IMAIL], except with no free
                     ;; insertion of linear-white-space, and the
                     ;; local-part MUST either be entirely enclosed in
                     ;; quotes or entirely unquoted

   token           = 1*255TCHAR

3. Example


   Here is a sample anonymous login between an IMAP client and server.
   In this example, "C:" and "S:" indicate lines sent by the client and
   server respectively.  If such lines are wrapped without a new "C:" or
   "S:" label, then the wrapping is for editorial clarity and is not
   part of the command.

   Note that this example uses the IMAP profile [IMAP4] of SASL.  The
   base64 encoding of challenges and responses, as well as the "+ "
   preceding the responses are part of the IMAP4 profile, not part of
   SASL itself.  Newer profiles of SASL will include the client message
   with the AUTHENTICATE command itself so the extra round trip below
   (the server response with an empty "+ ") can be eliminated.

   In this example, the user's opaque identification token is "sirhc".

        S: * OK IMAP4 server ready
        C: A001 CAPABILITY
        S: * CAPABILITY IMAP4 IMAP4rev1 AUTH=CRAM-MD5 AUTH=ANONYMOUS
        S: A001 OK done
        C: A002 AUTHENTICATE ANONYMOUS
        S: +
        C: c2lyaGM=
        S: A003 OK Welcome, trace information has been logged.





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