This reverts commit a030abdefc54470394a2a44008e02f3b3d0510ec.
This commit causes a connection to be leaked if there is a race with
another concurrent RPC.
* In connection pool, there is no guarantee that .reap() cannot execute the same time as .Shutdown() is called. It also did not benefit to eval shutdown when a select is run on the shutdown channel.
* In server, same principle applies to handleConsulConn. Since we also have a shutdown channel, it makes more to use this than to loop on a bool variable.
Namely, don't check the DNS names in TLS certificates when connecting to
other servers.
As of golang 1.3, crypto/tls no longer natively supports doing partial
verification (verifying the cert issuer but not the hostname), so we
have to disable verification entirely and then do the issuer
verification ourselves. Fortunately, crypto/x509 makes this relatively
straightforward.
If the "server_name" configuration option is passed, we preserve the
existing behavior of checking that server name everywhere.
No option is provided to retain the current behavior of checking the
remote certificate against the local node name, since that behavior
seems clearly buggy and unintentional, and I have difficulty imagining
it is actually being used anywhere. It would be relatively
straightforward to restore if desired, however.