ManageSieve Protocol: QUOTA/MAXSTORAGE Response Code

Sieve scripts allow users to filter incoming email. Using the ManageSieve protocol , users can securely manage their Sieve scripts on a remote server. This protocol allows a user to have multiple scripts on the server. To limit the resources required for script storage and execution, the server may refuse to accept a newly uploaded script based on site-defined quota constraints. All queries from a ManageSieve client are replied to with either an OK, NO, or BYE response. Each response may be followed by a response code to describe the event in a more detailed machine-parsable fashion (see , Section 1.3). The ManageSieve protocol defines specific response codes to notify the client about exceeded quota. The following quota response codes are currently defined: This generic response code is returned to indicate that some unspecified quota is exceeded. This is used when no more detailed response code is applicable. This response code is returned when the size of the currently uploaded script exceeds the limit. This response code is returned when the number of private scripts of this user exceeds the limit. This document defines a new quota response code that indicates that the total amount of storage occupied by the user's private Sieve scripts exceeds the site-defined quota constraint.

This document defines the following new response code for ManageSieve (, Section 1.3): QUOTA/MAXSTORAGE If this response code is returned in the NO/BYE response, it means that the command would have placed the user above the site-defined limit on the total amount of storage occupied by the user's private Sieve scripts. If this response code is returned in the OK response, it can mean that the user is near its quota or that the user exceeded its quota, but the server supports soft quotas. This response code is a more specific version of the QUOTA response code defined in . This extends the ManageSieve ABNF (, Section 4) as follows:

Thanks to Alexey Melnikov for comments and suggestions.

The following requests IANA to register a new ManageSieve response code according to the IANA registration template specified in :

Please register the following ManageSieve response code: QUOTA/MAXSTORAGE NONE If this response code is returned in the NO/BYE response, it means that the command would have placed the user above the site-defined limit on the total amount of storage occupied by the user's private Sieve scripts. If this response code is returned in the OK response, it can mean that the user is near its quota or that the user exceeded its quota, but the server supports soft quotas. This response code is a more specific version of the QUOTA response code. [RFCXXXX] ]]> IESG.

Security considerations are discussed in . This document only registers a new response code for the ManageSieve protocol and as such it does not introduce any additional security concerns.