On 14/11/2023 14:59 EET Kees van Vloten <keesvanvloten@gmail.com> wrote:
Hi all,
After upgrading Debian Bullseye (Dovecot 2.3.13) to Bookworm (Dovcecot 2.3.19), submission-login returns an error on Kerberos authentication: "Client sent invalid command: Command line is too long".
When I initially set this up on Bullseye I have seen the same issue, but adding "imap_max_line_length = 2M" solved it.
Now with 2.3.19 kerberos authentication still works (with this setting) for imap connections but it stopped working for submission.
Is there a new config setting for submission-login that I missed? Or is this a bug in 2.3.19?
- Kees.
You are probably running into a client-side issue. SMTP RFC says that all commands, including sasl ir, must be at most 998 bytes. Can you check if the client is sending AUTH KERBEROS which is longer than 998 lines?
After AUTH KERBEROS you can send longer lines.
Aki