OK, I found it. I changed the "DIR_MODE" directive in file /etc/adduser.conf from 0755 to 02770 and "USERGROUPS" directive from "yes" to "no". Now all new users belong to the same group and their home directories have 2770 permissions, which Maildir inherits. Since their shell is /usr/sbin/nologin this probably isn't a big security hole. I can even unset "mail_access_groups".
I know this wasn't Dovecot-specific, but sometimes we Linux novices thank a helping hand...
El 13/04/18 a les 08:31, Aki Tuomi ha escrit:
Dovecot will copy the mail root permissions when creating directories & folders.
Aki
On 12.04.2018 22:45, Rubén Fernández Asensio wrote:
Hello all,
I'm setting up an IMAP server with dovecot. I've set up system users with PAM authentication and Maildir maiboxes.
I'd like to share mailboxes among them, but regardless of what I try, I bump into filesystem permissions.
I want to have Maildirs created for new users with the right permissions. I even changed "UMASK" in file /etc/login.defs from 022 to 002, but the Maildirs are still created with 700 permissions:
ls -l /home/ximplet2/ total 4 drwx------ 9 ximplet2 users 4096 Apr 12 19:10 Maildir
Really there's no better way than running "chmod -R g=u /home/ximplet2/Maildir" and "chmod g+s /home/ximplet2/Maildir" for every user? Really??
I read that, before v.2, Dovecot had a "umask" option to do precisely want I need, but it was removed.
How are we supposed to use ACL with system users nowadays?
Rubeno
P.S: my doveconf -n:
# 2.2.31 (65cde28): /etc/dovecot/dovecot.conf # Pigeonhole version 0.4.19 (e5c7051) # OS: Linux 4.4.0-119-generic x86_64 Ubuntu 16.04.4 LTS auth_mechanisms = plain login auth_verbose = yes auth_verbose_passwords = plain mail_access_groups = kundividantoj mail_location = maildir:~/Maildir:LAYOUT=fs mail_plugins = acl managesieve_notify_capability = mailto managesieve_sieve_capability = fileinto reject envelope encoded-character vacation subaddress comparator-i;ascii-numeric relational regex imap4flags copy include variables body enotify environment mailbox date index ihave duplicate mime foreverypart extracttext imapsieve vnd.dovecot.imapsieve namespace { list = yes location = maildir:%%h/Maildir:INDEXPVT=~/Maildir/Komunujo/%%n prefix = Komunujo/%%n/ subscriptions = no type = shared } namespace inbox { inbox = yes location = mailbox Malnetujo { auto = subscribe comment = Mesaĝoj ne finitaj nek senditaj special_use = \Drafts } mailbox Rubujo { auto = subscribe autoexpunge = 120 days comment = Ĉi tien iras la forviŝitaj mesaĝoj special_use = \Trash } mailbox Senditujo { auto = subscribe special_use = \Sent } mailbox Spamujo { auto = create autoexpunge = 30 days comment = Mesaĝoj markitaj kiel ne deziritaj special_use = \Junk } prefix = subscriptions = yes type = private } passdb { driver = pam } plugin { acl = vfile acl_shared_dict = file:/var/lib/dovecot/kundividitaj/shared-mailboxes imapsieve_mailbox1_before = file:/etc/dovecot/sieve/imapsieve/report-spam.sieve imapsieve_mailbox1_causes = COPY FLAG imapsieve_mailbox1_name = Spamujo imapsieve_mailbox2_before = file:/etc/dovecot/sieve/imapsieve/report-ham.sieve imapsieve_mailbox2_causes = COPY imapsieve_mailbox2_from = Spamujo imapsieve_mailbox2_name = * sieve = file:~/sieve;active=~/.dovecot.sieve sieve_after = /etc/dovecot/sieve/final sieve_extensions = +vnd.dovecot.pipe +vnd.dovecot.debug sieve_global_extensions = +vnd.dovecot.pipe +vnd.dovecot.debug sieve_pipe_bin_dir = /usr/bin sieve_plugins = sieve_imapsieve sieve_extprograms } protocols = " imap lmtp sieve" service auth { unix_listener /var/spool/postfix/private/auth { group = postfix mode = 0660 user = postfix } unix_listener auth-userdb { group = mode = 0777 user = } } ssl = required ssl_cert = </etc/ssl/certs/ssl-cert-snakeoil.pem ssl_key = # hidden, use -P to show it userdb { driver = passwd } protocol lda { mail_plugins = acl sieve } protocol imap { mail_plugins = acl imap_acl imap_sieve
}