BDAT to DATA translation on submission service when checkpassword is involved

[Aki Tuomi]

> On 23/07/2021 01:22 Dan Conway <darkc0de at archnix6.net> wrote:
> 
>  
> Hello,
> 
> I'm having issues with Dovecot translating "BDAT" commands (CHUNKING) 
> into "DATA" commands when the backend does not support it in the 
> submission service. I use "checkpassword" to authenticate users and 
> judging by older mailing list entries the presence of "submission_*" 
> directives must be in place for Dovecot to translate. Even with these 
> directives set, the translation doesn't seem to occur.
> 
> checkpassword returns "director_tag=remote_smtp" (along with other 
> fields such as nopassword=y proxy=y) which in turn sets the backend host 
> to relay the connection to. I have a feeling the use of checkpassword 
> has something to do with this lack of translation.
> 
> If the "submission_*" directives must be in place for this translation 
> to occur, which ones are they? Can I return these fields from checkpassword?
> 
> 
> Output of doveconf -n:
> 
> # 2.3.15 (0503334ab1): /etc/dovecot/dovecot.conf
> # OS: Linux 4.15.0-147-generic x86_64 Ubuntu 18.04.5 LTS
> # Hostname: xyz
> auth_debug = yes
> auth_debug_passwords = yes
> auth_mechanisms = plain login
> auth_verbose = yes
> director_mail_servers = x.x.x.x at remote_smtp
> director_servers = x.x.x.x
> disable_plaintext_auth = no
> mail_log_prefix = "%Us(%u) [%r]: "
> passdb {
>    args = /usr/local/bin/checkpassword
>    driver = checkpassword
> }
> protocols = " imap pop3 submission"
> service anvil {
>    client_limit = 3553
> }
> service auth {
>    client_limit = 3550
> }
> service director {
>    fifo_listener login/proxy-notify {
>      mode = 0600
>      user = $default_login_user
>    }
>    inet_listener {
>      address = x.x.x.x
>      port = 9090
>    }
>    unix_listener director-admin {
>      mode = 0600
>    }
>    unix_listener login/director {
>      mode = 0666
>    }
> }
> service imap-login {
>    executable = imap-login director
>    inet_listener imap {
>      address = x.x.x.x
>      port = 143
>    }
>    inet_listener imaps {
>      address = x.x.x.x
>      port = 993
>      ssl = yes
>    }
>    process_limit = 1000
>    process_min_avail = 0
>    service_count = 1
> }
> service imap {
>    process_limit = 2048
>    process_min_avail = 0
>    service_count = 1
>    vsz_limit = 384 M
> }
> service pop3-login {
>    executable = pop3-login director
>    inet_listener pop3 {
>      address = x.x.x.x
>      port = 110
>    }
>    inet_listener pop3s {
>      address = x.x.x.x
>      port = 995
>      ssl = yes
>    }
>    process_limit = 450
> }
> service pop3 {
>    process_limit = 190
>    process_min_avail = 0
>    service_count = 1
> }
> service submission-login {
>    executable = submission-login director
>    inet_listener smtp {
>      address = x.x.x.x
>      port = 25
>    }
>    inet_listener smtps {
>      address = x.x.x.x
>      port = 465
>      ssl = yes
>    }
>    inet_listener submission {
>      address = x.x.x.x
>      port = 587
>    }
>    process_limit = 2000
> }
> ssl_cert = </etc/...
> ssl_dh = # hidden, use -P to show it
> ssl_key = # hidden, use -P to show it
> ssl_min_protocol = TLSv1.1
> submission_backend_capabilities =
> submission_host = x.x.x.x
> submission_relay_host = x.x.x.x
> submission_relay_port = 465
> submission_relay_ssl = smtps
> submission_relay_trusted = yes
> userdb {
>    args = /etc/dovecot/userdb.conf
>    driver = ldap
> }
> protocol imap {
>    imap_logout_format = bytes=%i/%o, del=%e
>    mail_max_userip_connections = 20
> }
> protocol pop3 {
>    mail_max_userip_connections = 20
>    pop3_logout_format = top=%t/%p, retr=%r/%b, del=%d/%m, size=%s
> }
> protocol submission {
>    mail_max_userip_connections = 10
> }
> local_name *.domain.com {
>    ssl_cert = </etc/...
>    ssl_key = # hidden, use -P to show it
> }

Hi!

Submission service works from backend, not proxy. 

Aki