[JAMES-3788] Support for HAProxy Proxy Protocol

• Type: New Feature
• Status: Closed
• Priority: Minor
• Resolution: Fixed
• Fix Version/s: 3.8.0
• Component/s: protocols
• Assignee: Unassigned
• Reporter: ouvtam
• Created: 06/Jul/22 06:07
• Updated: 20/Aug/22 06:10
• Resolved: 20/Aug/22 06:10

Description

As proposed in the gitter channel I would like to add support for HAProxy's PROXY protocol (https://www.haproxy.org/download/2.7/doc/proxy-protocol.txt).

This allows to run James behind HAProxy (i.e. load balancing multiple James instances). In order to properly support the proxy protocol James needs to parse the provided PROXY arguments from HAProxy (remote ip address, remote port etc.) and store it in the SMTPSession for further processing (e.g. DNSRBL check, Authorized Networks etc.). Otherwise James uses HAProxy's address (e.g. localhost) as remote address.

For instance, HAProxy sends following line after connecting:

"PROXY TCP4 255.255.255.255 255.255.255.255 65535 65535\r\n" 

Netty already provides a codec for HAProxy's protocol (io.netty.handler.codec.haproxy), so this can be implemented in the transport layer of James.

Issue Links

• requires: JAMES-3715 Upgrade to Netty 4.1
• links to: GitHub Pull Request #1132
• links to: GitHub Pull Request #1138