On 08/12/2023 14:45 EET John Fawcett <john@voipsupport.it> wrote:

Hi

does anyone happen to know the username under which dovecot accesses the certificate and key files when connecting to a mariadb database with ssl? I can't seem to get dovecot to read the files without a "other" readable bit set.

I have dovecot users in mysql with the following connect string in dovecot-sql.conf.ext

connect = host=x.x.x host=y.y.y host=z.z.z dbname=maildb user=mailuser password=xxxxxx
ssl_ca=/etc/ssl/mysql/ca-cert.pem
ssl_cert=/etc/ssl/mysql/client-cert.pem
ssl_key=/etc/ssl/mysql/client-key.pem
ssl_verify_server_cert=yes

The certificate and key files in /etc/ssl/mysql/ are owned by root with group users:

ls -l /etc/ssl/mysql

total 12 -r--r--r--. 1 root root  2041 Jun 22 15:32 ca-cert.pem -r--r--r--. 1 root users 1907 Jun 22 15:32 client-cert.pem -r--r--r--. 1 root users 3272 Jun 22 15:32 client-key.pem

For my test dovecot, dovenull and vmail are all members of group users:

grep users /etc/group users:x:100:postfix,dovecot,dovenull,vmail

If I remove the "other" readable attribute on the certificate and key files, dovecot complains it can't connect to the db server:

auth: Error: mysql(x.x.x): Connect failed to database (maildb): TLS/SSL error: Permission denied (13) - waiting for 1 seconds before retry

I realize it only adds marginal security to not have these files world readable, but still it is puzzling why dovecot cannot read them in that case. Can anyone see what I am missing?

Thanks

John

The group depends on process, usually dovecot uses four different identities:

root, dovecot:dovecot, dovenull:dovenull and vmail:vmail (or per-user identity).

Any extra groups are removed during execution, but if you want, you can use

https://doc.dovecot.org/configuration_manual/service_configuration/#extra-gr...

like

service imap { ... extra_groups = users }

to grant the process users membership during execution.

Aki

John Fawcett skrev den 2023-12-08 13:45:

I realize it only adds marginal security to not have these files world readable, but still it is puzzling why dovecot cannot read them in that case. Can anyone see what I am missing?

dovecot does imho not run anywhere with users group ?

default in gentoo all users is default in /home group subdirs, did you make mistakes here ?

private & public keys should only be owned and grouped as root, why ?, dovecot runs on ports below 1024, so all auth is loaded as root where it drops priveleges later !

dont make secureity mistakes