Add TLS certificate for email relaying in lists.alpinelinux.org
As subject states, lists.alpinelinux.org doesn’t offer a certificate for using STARTTLS in MTA to MTA communication. This can be checked by:
$ openssl s_client -connect lists.alpinelinux.org:25 -starttls smtp CONNECTED(00000003) didn't find starttls in server response, try anyway... 22101338425312:error:1400410B:SSL routines:CONNECT_CR_SRVR_HELLO:wrong version number:/usr/src/lib/libssl/ssl_pkt.c:386: --- no peer certificate available --- No client certificate CA names sent --- SSL handshake has read 208 bytes and written 0 bytes --- New, (NONE), Cipher is (NONE) Secure Renegotiation IS NOT supported Compression: NONE Expansion: NONE No ALPN negotiated SSL-Session: Protocol : TLSv1.2 Cipher : 0000 Session-ID: Session-ID-ctx: Master-Key: Start Time: 1540317980 Timeout : 7200 (sec) Verify return code: 0 (ok) ---
Under some email servers setups such as mine, email isn’t relayed if the remote doesn’t provides STARTTLS.
(from redmine: issue id 9573, created on 2018-10-24)