Bug 2830

Summary: Add option to set TCP_USER_TIMEOUT on linux
Product: Portable OpenSSH Reporter: Julien Wallior <wallior>
Component: sshdAssignee: Assigned to nobody <unassigned-bugs>
Status: NEW ---    
Severity: enhancement CC: dtucker
Priority: P5    
Version: 7.6p1   
Hardware: Other   
OS: Linux   
Attachments:
Description Flags
Adds support for TCP_USER_TIMEOUT. none

Description Julien Wallior 2018-02-01 10:08:04 AEDT
Created attachment 3118 [details]
Adds support for TCP_USER_TIMEOUT.

Since 2010, Linux has had a socket option to be able to set a custom timeout of how long a TCP session can stay up if the link drops (default is ~15 set by tcp_retries1/2). https://patchwork.ozlabs.org/patch/62889/

The attached patch lets the user set the TCP_USER_TIMEOUT on both sshd and ssh.
Comment 1 Darren Tucker 2018-02-01 11:57:38 AEDT
I don't think we want to add support for a platform-specific socket option like this.

On the client side you can implement it as an external ProxyCommand dialer that sets the option and passes the connected socket back via ProxyUseFdpass.
Comment 2 Julien Wallior 2018-02-02 01:15:42 AEDT
> On the client side you can implement it as an external ProxyCommand
> dialer that sets the option and passes the connected socket back via
> ProxyUseFdpass.
I see how this will work on the client side. This socket option needs to be set on the server side too. Any suggestion how to do that?