BUG: _presence_ of valid openssl.cnf Option = 'ServerPreference' causes Dovecot submission relay FAIL: "failed: Failed to initialize SSL: ..."

[PGNet Dev]

bump

On 8/24/20 5:17 PM, PGNet Dev wrote:
>   I've
> 
> 	dovecot --version
> 		2.3.10.1 (a3d0e1171)
> 	openssl version
> 		OpenSSL 1.1.1g FIPS  21 Apr 2020
> 
> , atm on Fedora32.
> 
> I configure
> 
> 	/etc/pki/tls/openssl.cnf
> 
> to set preferences for apps' usage, e.g. Postfix etc; Typically, here
> 
> 	cat /etc/pki/tls/openssl.cnf
> 
> 		openssl_conf = default_conf
> 
> 		[default_conf]
> 		ssl_conf = ssl_sect
> 
> 		[ssl_sect]
> 		system_default = system_default_sect
> 
> 		[system_default_sect]
> 		MinProtocol = TLSv1.2
> 		Ciphersuites = TLS_CHACHA20_POLY1305_SHA256:TLS_AES_256_GCM_SHA384:TLS_AES_128_GCM_SHA256
> 		CipherString = ECDHE-ECDSA-CHACHA20-POLY1305:ECDHE-RSA-CHACHA20-POLY1305:ECDHE-ECDSA-AES256-GCM-SHA384:ECDHE-ECDSA-AES128-GCM-SHA256:ECDHE-RSA-AES256-GCM-SHA384:ECDHE-RSA-AES128-GCM-SHA256:ECDHE-ECDSA-AES256-SHA384:ECDHE-ECDSA-AES128-SHA256:ECDHE-RSA-AES256-SHA384:ECDHE-RSA-AES128-SHA256
> 		Options = PrioritizeChaCha,ServerPreference
> 
> However, any/all sends from local client via Dovecot submission -- from an instance on the same server --  FAILS with that^^ openssl.cnf,
> 
> 	==> /var/log/dovecot/dovecot.log <==
> 		...
> 		2020-08-24 17:04:42 submission(testuser at example.com)<D4c5c6itUg2sHgsH>: Error: smtp-client: conn int.mx.example.net:465 (10.0.4.65:465) [1]: connect(int.mx.example.net:465) failed: Failed to initialize SSL: Couldn't initialize SSL context: Can't load SSL certificate: error:14187180:SSL routines:ssl_do_config:bad value: section=system_default, cmd=Options, arg=ServerPreference,PrioritizeChaCha
> 		2020-08-24 17:04:42 submission(testuser at example.com)<D4c5c6itUg2sHgsH>: Error: Failed to establish relay connection: Failed to connect to remote server
> 		...
> 
> editing,
> 
> -		Options = PrioritizeChaCha,ServerPreference
> +		Options = PrioritizeChaCha
> 
> cures the error
> 
> 	==> /var/log/dovecot/dovecot.log <==
> 		...
> 		2020-08-24 17:08:04 submission(testuser at example.com)<Uow+f6itZg2sHgsH>: Info: Successfully relayed message: from=<testuser at example.com>, size=433, id=Mh4pJWRWRF9jHQAAVDn7pA, nrcpt=1, reply=`250 2.0.0 Ok: queued as 4Bb8TJ4VQbz7v6t'
> 		...
> 
> checking ssl docs
> 
> 	https://www.openssl.org/docs/man1.1.1/man3/SSL_CONF_cmd.html
> 
> BOTH are valid 'Options',
> 
> 	...
> 	ServerPreference: use server and not client preference order when determining which cipher suite, signature algorithm or elliptic curve to use for an incoming connection. Equivalent to SSL_OP_CIPHER_SERVER_PREFERENCE. Only used by servers.
> 
> 	PrioritizeChaCha: prioritizes ChaCha ciphers when the client has a ChaCha20 cipher at the top of its preference list. This usually indicates a mobile client is in use. Equivalent to SSL_OP_PRIORITIZE_CHACHA. Only used by servers.
> 	...
> 
> 
> The mere presence of that option in a system-wide openssl.cnf shouldn't cause a Dovecot submission failure.
>