CourierIMAPSharedFolders

Courier-IMAP has 2 implementation for shared folders, virtual shared folders and filesystem permission-based shared folders. We choose virtual shared folders because we don't need and want our users to have shell access to the server. A project account will be used to put project folders in which will store the e-mail messages assigned to it's project. Virtual shared folders with Courier-IMAP requires an index file in /etc/courier/shared/ which contains a list with accounts whom have folder sharing enabled, we only need this line here:

project 103     104     /var/mail/      project@openprojectservices.org/

Where the values are (seperated by tabs):

• name of the account
• the uid of the owner of the mailboxes (usually postfix)
• the gid of the owner of the mailboxes (usually postfix)
• the virtual home dir of the account
• the mail dir path (we use e-mail address as folder name)

We only allow the project account to have shared folders, to allow other users to have shared folders too consult the Courier-IMAP documentation on shared folders.

Folders in the project mail dir are checked for ACL entries containing a users loginname and if one is found the user will gain access to that folder with the rights in the ACL entry.

More information about Courier-IMAP shared folders can be found here.

Note: The Create ACL Tool(create acl tool instructions) creates ACLs for usernames, this means people logging in with their e-mail address won't see the shared folders, they will only be visible when logged in with username.

-- BastiaanGrutters - 10 Nov 2005