Allow setting the server hostname for TLS connection

[ameir]

When using SAN certs, hostname verification is enforced. If the server hostname in server_addr doesn't match one of the names in the cert, thenthe connection fails. This PR allows you to specify an allowed hostname. The use-case for this is that we have auto-generated certs per node in AWS,but are establishing the tunnel through an NLB. The NLB hostname does not match what is in the cert, so the connection fails without this patch.

[mmatczuk]

If the server hostname in server_addr doesn't match one of the names in the cert, thenthe connection fails.

In my view this is a generally expected behavior and adding the change would be confusing for other users.

I believe your problem shall be solved by a better cert generation and DNS service registration.

[ameir]

In my company, each host automatically gets a cert generated by our internal CA, and with an internal common name. That common name is not publicly resolvable, and we are not allowed to use any certificates other than these, as there's automation around revocation and renewal and such. The hosts can be made reachable via a load balancer, which will have an entirely different hostname. We need a way to override the name that's checked in the cert, and this patch accomplishes it. I think lots of folks use internal CAs, and this should definitely help.

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On Sun, Jul 15, 2018, 2:11 AM Michał Matczuk ***@***.***> wrote: If the server hostname in server_addr doesn't match one of the names in the cert, thenthe connection fails. In my view this is a generally expected behavior and adding the change would be confusing for other users. I believe your problem shall be solved by a better cert generation and DNS service registration. — You are receiving this because you authored the thread. Reply to this email directly, view it on GitHub <#83 (comment)>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AAW2OkAZCGyM9dJ2_uWPoT3BLLDOxi3Aks5uGt0YgaJpZM4VKt6g> .