Anonymous mode:
Implementations MAY advertise the ANONYMOUS SASL mechanism
[SASL-ANON]. This indicates that the server supports ANONYMOUS
SIEVE
script syntax verification. Only the CAPABILITY, PUTSCRIPT and
LOGOUT commands are available to the anonymous user. All other
commands defined in the base ManageSieve protocol MUST give NO
responses, however ManageSieve extensions MAY allow other commands
in
the ANONYMOUS Sieve script verification mode. Furthermore the
PUTSCRIPT command MUST NOT persistently store any data. In this
mode
a positive response to the PUTSCRIPT command indicates that the
given
script does not have any syntax errors.
This conflates two things (which is generally bad for extensibility):
anonymous authentication, with script syntax verification. It would
be better not to conflate these things, in case there is ever any
other purpose to anonymous mode, or any need for script syntax
verification while authenticated. How about a TRYSCRIPT method that
acts as PUTSCRIPT but never stores the script? Then the anonymous
mode can be defined, in this version of managesieve, as allowing
TRYSCRIPT but not PUTSCRIPT.
Lisa