Cannot send with StartTLS on Postfix - email

Question

I setup a mailserver with a couple different tutorials of Postfix and Dovecot. None of them seemed to actually work 100%. I did get it working with IMAP with SSL on 993 and SMTP with StartTLS on 465. However, mxtoolbox said this might be an open relay.
I wanted to get rid of this error so I added in some smtp restrictions. It gets rid of the error, but now I cannot send via mail clients.
It just sits on sending for a long time and then times out. I pulled the restrictions off of a question here, including fixes to the tutorials to get it working before.
Here is the master.cf:
#
# Postfix master process configuration file. For details on the format
# of the file, see the master(5) manual page (command: "man 5 master" or
# on-line: http://www.postfix.org/master.5.html).
#
# Do not forget to execute "postfix reload" after editing this file.
#
# ==========================================================================
# service type private unpriv chroot wakeup maxproc command + args
# (yes) (yes) (no) (never) (100)
# ==========================================================================
smtp inet n - y - - smtpd
#smtp inet n - y - 1 postscreen
#smtpd pass - - y - - smtpd
#dnsblog unix - - y - 0 dnsblog
#tlsproxy unix - - y - 0 tlsproxy
submission inet n - y - - smtpd
# -o syslog_name=postfix/submission
# -o smtpd_tls_security_level=encrypt
# -o smtpd_sasl_auth_enable=yes
# -o smtpd_reject_unlisted_recipient=no
# -o smtpd_client_restrictions=$mua_client_restrictions
# -o smtpd_helo_restrictions=$mua_helo_restrictions
# -o smtpd_sender_restrictions=$mua_sender_restrictions
# -o smtpd_recipient_restrictions=
# -o smtpd_relay_restrictions=permit_sasl_authenticated,reject
# -o milter_macro_daemon_name=ORIGINATING
465 inet n - y - - smtpd
# -o syslog_name=postfix/smtps
# -o smtpd_tls_wrappermode=yes
# -o smtpd_sasl_auth_enable=yes
# -o smtpd_reject_unlisted_recipient=no
# -o smtpd_client_restrictions=$mua_client_restrictions
# -o smtpd_helo_restrictions=$mua_helo_restrictions
# -o smtpd_sender_restrictions=$mua_sender_restrictions
# -o smtpd_recipient_restrictions=
# -o smtpd_relay_restrictions=permit_sasl_authenticated,reject
# -o milter_macro_daemon_name=ORIGINATING
#628 inet n - y - - qmqpd
pickup unix n - y 60 1 pickup
cleanup unix n - y - 0 cleanup
qmgr unix n - n 300 1 qmgr
#qmgr unix n - n 300 1 oqmgr
tlsmgr unix - - y 1000? 1 tlsmgr
rewrite unix - - y - - trivial-rewrite
bounce unix - - y - 0 bounce
defer unix - - y - 0 bounce
trace unix - - y - 0 bounce
verify unix - - y - 1 verify
flush unix n - y 1000? 0 flush
proxymap unix - - n - - proxymap
proxywrite unix - - n - 1 proxymap
smtp unix - - y - - smtp
relay unix - - y - - smtp
# -o smtp_helo_timeout=5 -o smtp_connect_timeout=5
showq unix n - y - - showq
error unix - - y - - error
retry unix - - y - - error
discard unix - - y - - discard
local unix - n n - - local
virtual unix - n n - - virtual
lmtp unix - - y - - lmtp
anvil unix - - y - 1 anvil
scache unix - - y - 1 scache
#
# ====================================================================
# Interfaces to non-Postfix software. Be sure to examine the manual
# pages of the non-Postfix software to find out what options it wants.
#
# Many of the following services use the Postfix pipe(8) delivery
# agent. See the pipe(8) man page for information about ${recipient}
# and other message envelope options.
# ====================================================================
#
# maildrop. See the Postfix MAILDROP_README file for details.
# Also specify in main.cf: maildrop_destination_recipient_limit=1
#
maildrop unix - n n - - pipe
flags=DRhu user=vmail argv=/usr/bin/maildrop -d ${recipient}
#
# ====================================================================
#
# Recent Cyrus versions can use the existing "lmtp" master.cf entry.
#
# Specify in cyrus.conf:
# lmtp cmd="lmtpd -a" listen="localhost:lmtp" proto=tcp4
#
# Specify in main.cf one or more of the following:
# mailbox_transport = lmtp:inet:localhost
# virtual_transport = lmtp:inet:localhost
#
# ====================================================================
#
# Cyrus 2.1.5 (Amos Gouaux)
# Also specify in main.cf: cyrus_destination_recipient_limit=1
#
#cyrus unix - n n - - pipe
# user=cyrus argv=/cyrus/bin/deliver -e -r ${sender} -m ${extension}
${user}
#
# ====================================================================
# Old example of delivery via Cyrus.
#
#old-cyrus unix - n n - - pipe
# flags=R user=cyrus argv=/cyrus/bin/deliver -e -m ${extension} ${user}
#
# ====================================================================
#
# See the Postfix UUCP_README file for configuration details.
#
uucp unix - n n - - pipe
flags=Fqhu user=uucp argv=uux -r -n -z -a$sender - $nexthop!rmail
($recipient)
#
# Other external delivery methods.
#
ifmail unix - n n - - pipe
flags=F user=ftn argv=/usr/lib/ifmail/ifmail -r $nexthop ($recipient)
bsmtp unix - n n - - pipe
flags=Fq. user=bsmtp argv=/usr/lib/bsmtp/bsmtp -t$nexthop -f$sender
$recipient
scalemail-backend unix - n n - 2 pipe
flags=R user=scalemail argv=/usr/lib/scalemail/bin/scalemail-store
${nexthop} ${user} ${extension}
mailman unix - n n - - pipe
flags=FR user=list argv=/usr/lib/mailman/bin/postfix-to-mailman.py
${nexthop} ${user}
This is my main.cf
# See /usr/share/postfix/main.cf.dist for a commented, more complete version
# Debian specific: Specifying a file name will cause the first
# line of that file to be used as the name. The Debian default
# is /etc/mailname.
#myorigin = /etc/mailname
smtpd_banner = $myhostname ESMTP $mail_name (Raspbian) This is not an open
relay.
biff = no
# appending .domain is the MUA's job.
append_dot_mydomain = no
# Uncomment the next line to generate "delayed mail" warnings
#delay_warning_time = 4h
readme_directory = no
# TLS parameters
smtpd_tls_cert_file = /root/fullchain.pem
smtpd_tls_key_file = /root/privkey.pem
smtpd_use_tls = yes
smtpd_tls_auth_only = yes
smtpd_sasl_type = dovecot
smtpd_sasl_path = private/auth
smtpd_sasl_auth_enable = yes
smtpd_relay_restrictions =
# subject even authenticated users and trusted networks
# to the policy check
check_policy_service inet:127.0.0.1:10031
permit_mynetworks
reject_unknown_sender_domain
permit_sasl_authenticated
defer_unauth_destination
smtpd_recipient_restrictions =
permit_mynetworks
permit_sasl_authenticated
# we exclude our networks and SASL authenticated users
# from all further checks.
# since I don't know if the policy service is relevant
# for unauthenticated mail, I commented it out here
# check_policy_service inet:127.0.0.1:10031
warn_if_reject reject_non_fqdn_hostname
warn_if_reject reject_non_fqdn_sender
reject_invalid_hostname
reject_unknown_sender_domain
smtpd_data_restrictions = reject_unauth_pipelining
# See /usr/share/doc/postfix/TLS_README.gz in the postfix-doc package for
# information on enabling SSL in the smtp client.
myhostname = mail.smbecker.tk
alias_maps = hash:/etc/aliases
alias_database = hash:/etc/aliases
myorigin = /etc/mailname
mydestination = localhost
relayhost =
mynetworks = 0.0.0.0/0 [::ffff:127.0.0.0]/104 [::1]/128
mailbox_size_limit = 0
recipient_delimiter = +
inet_interfaces = all
#Handing off local delivery to Dovecot's LMTP, and telling it where to store
mail
virtual_transport = lmtp:unix:private/dovecot-lmtp
#Virtual domains, users, and aliases
virtual_mailbox_domains = mysql:/etc/postfix/mysql-virtual-mailbox-
domains.cf
virtual_mailbox_maps = mysql:/etc/postfix/mysql-virtual-mailbox-maps.cf
virtual_alias_maps = mysql:/etc/postfix/mysql-virtual-alias-maps.cf
inet_protocols = ipv4
Basically, I want to be able to send and receive mail from anywhere as long as the domain and user exist on the server and authenticate with IMAP SSL on 993 and SMTP StartTLS on 465. The RPI has no firewall setup, but has a hardware firewall to the web only allowing ports 25,993,465. The client I am having an issue with though is a local PC without a firewall in between.
Before I made the changes to main.cf regarding:
smtpd_relay_restrictions =
# subject even authenticated users and trusted networks
# to the policy check
check_policy_service inet:127.0.0.1:10031
permit_mynetworks
reject_unknown_sender_domain
permit_sasl_authenticated
defer_unauth_destination
smtpd_recipient_restrictions =
permit_mynetworks
permit_sasl_authenticated
# we exclude our networks and SASL authenticated users
# from all further checks.
# since I don't know if the policy service is relevant
# for unauthenticated mail, I commented it out here
# check_policy_service inet:127.0.0.1:10031
warn_if_reject reject_non_fqdn_hostname
warn_if_reject reject_non_fqdn_sender
reject_invalid_hostname
reject_unknown_sender_domain
smtpd_data_restrictions = reject_unauth_pipelining
# See /usr/share/doc/postfix/TLS_README.gz in the postfix-doc package for
# information on enabling SSL in the smtp client.
I was able to telnet on port 465. Now, I cannot. The mail log shows:
Jan 6 18:54:41 raspberrypi postfix/smtpd[30109]: lost connection after
CONNECT from unknown[10.100.100.1]
Before making changes, it just said:
smtpd_recipient_restrictions =
With nothing there.
Any one got any ideas on how to fix this?
Then I can start on Roundcube, DKIM, SFP, DMARC, and getting my ISP to create a PTR for me.

Answer 1

Basically, deployment of Postfix is a bit sophisticated.
My first Tip: I am using a wonderful set of Tools regarding deploy an open-source mail server called "Zimbra". It will take care of all you need and gives you a web Interface for management and UI.
Btw I can help you to fix your deployment fellow like this.
My second Tip: You may check firewalls, access permission and /etc/defaults if everything is fine. Sometimes simple Issue causes the Problem.

Answer 2

There is a tls log setting that will help with TLS issues:
http://www.postfix.org/TLS_README.html
Solution was to add:
smtpd_tls_loglevel = 2
which then showed me where the issue was.
Issue was here:
smtpd_relay_restrictions =
# subject even authenticated users and trusted networks
# to the policy check
check_policy_service inet:127.0.0.1:10031
I commented out the:
check_policy_service inet:127.0.0.1:10031
Now everything works and mxtoolbox shows it is not an open relay because it rejects their test message.