[Dovecot] namespaces and behaviour of LIST and SELECT with leading ~

Hi

One weirdness when going through the code:

(We are migrating from WU-IMAP and have users with a mixture of ~/IMAP/ and ~/Mail/ for storing mail - but all user INBOX=~/.email thankfully. IMAP client config is even more random and we have 1800 users.

I have been playing with namespaces to translate various prefixes ala:

default_mail_env = mbox:%h/:INBOX=%h/.email:INDEX=/var/cache/dovecot/%n # Note lack of IMAP ^^^ (So clients can use ~/IMAP or ~/Mail - we have a # historic mixture) full_filesystem_access = no namespace private { separator = / inbox = yes prefix = hidden = no location = mbox:.email } namespace private { separator = / prefix = hidden = no location = mbox:IMAP/ } namespace private { separator = / prefix = IMAP/ hidden = no location = mbox:IMAP/ } namespace private { separator = / prefix = ~/IMAP/ hidden = no location = mbox:IMAP/ }

User tstest has INBOX in ~/.email and mail folders in ~/IMAP/ all in mbox format:

Here's a sample conversation:

• OK dovecot ready. 1 login tstest ******* 1 OK Logged in. 1 list "" %

• LIST (\NoInferiors \UnMarked) "/" INBOX

• LIST (\NoInferiors) "/" "Trash"

• LIST (\NoInferiors) "/" "Queue"

• LIST (\NoInferiors) "/" "Sent"

• LIST (\NoInferiors) "/" "Drafts"

• LIST (\NoInferiors) "/" "Blah" 1 OK List completed.

  Good

1 list "" IMAP/%

• LIST (\NoInferiors) "/" "IMAP/Trash"

• LIST (\NoInferiors) "/" "IMAP/Queue"

• LIST (\NoInferiors) "/" "IMAP/Sent"

• LIST (\NoInferiors) "/" "IMAP/Drafts"

• LIST (\NoInferiors) "/" "IMAP/Blah" 1 OK List completed.

  Good

1 list "" ~/IMAP/% 1 OK List completed.

Oops (being caught by mbox_is_valid_mask as prefix begins with ~ and

the client supplied prefix is being tested, not the virtual one after namespace prefix substitution)

But...

1 select Blah

• FLAGS (\Answered \Flagged \Deleted \Seen \Draft)

• OK [PERMANENTFLAGS (\Answered \Flagged \Deleted \Seen \Draft \*)] Flags permitted.* 5 EXISTS

• 0 RECENT

• OK [UNSEEN 1] First unseen.

• OK [UIDVALIDITY 1090326264] UIDs valid

• OK [UIDNEXT 6] Predicted next UID 1 OK [READ-WRITE] Select completed.

  Yes

1 select IMAP/Blah

• FLAGS (\Answered \Flagged \Deleted \Seen \Draft)

• OK [PERMANENTFLAGS (\Answered \Flagged \Deleted \Seen \Draft \*)] Flags permitted.* 5 EXISTS

• 0 RECENT

• OK [UNSEEN 1] First unseen.

• OK [UIDVALIDITY 1090326264] UIDs valid

• OK [UIDNEXT 6] Predicted next UID 1 OK [READ-WRITE] Select completed.

  Yes

1 select ~/IMAP/Blah

• FLAGS (\Answered \Flagged \Deleted \Seen \Draft)

• OK [PERMANENTFLAGS (\Answered \Flagged \Deleted \Seen \Draft \*)] Flags permitted.* 5 EXISTS

• 0 RECENT

• OK [UNSEEN 1] First unseen.

• OK [UIDVALIDITY 1090326264] UIDs valid

• OK [UIDNEXT 6] Predicted next UID 1 OK [READ-WRITE] Select completed.

  Oo - this works despite the ~

I would argue that with namespace {} directives, the behaviour of SELECT is correct. I would suggest that it may be better to test the final translated path thus:

if full_filesystem_access = yes let anything go. else make sure that final translated mail path is identical OR a subpath of the default_mail_env mbox folder path. (INBOX is a special case and can be matched as well)

This is a suggestion - what do you think? I'd have a go myself but I don't yet feel competant with the dovecot code.

Best wishes

Tim

Tim J Southerwood