Fix sslinline for connections after the first one.

The sslinline functionality would delete the required keys after
upgrading the first connection.
This commit adds the sslinine key to
the isDriverSetting so that it is not sent to
Posgres which would cause a crash.
It also removes the delete of the keys necessary for sslinline to allow
SSL upgrades for connections after the first one.

conn.go

@@ -1106,7 +1106,7 @@ func isDriverSetting(key string) bool {
 		return true
 	case "password":
 		return true
-	case "sslmode", "sslcert", "sslkey", "sslrootcert":
+	case "sslmode", "sslcert", "sslkey", "sslrootcert", "sslinline":
 		return true
 	case "fallback_application_name":
 		return true

ssl.go

@@ -59,9 +59,6 @@ func ssl(o values) (func(net.Conn) (net.Conn, error), error) {
 		return nil, err
 	}
 
-	// This pseudo-parameter is not recognized by the PostgreSQL server, so let's delete it after use.
-	delete(o, "sslinline")
-
 	// Accept renegotiation requests initiated by the backend.
 	//
 	// Renegotiation was deprecated then removed from PostgreSQL 9.5, but
@@ -89,9 +86,6 @@ func sslClientCertificates(tlsConf *tls.Config, o values) error {
 	sslinline := o["sslinline"]
 	if sslinline == "true" {
 		cert, err := tls.X509KeyPair([]byte(o["sslcert"]), []byte(o["sslkey"]))
-		// Clear out these params, in case they were to be sent to the PostgreSQL server by mistake
-		o["sslcert"] = ""
-		o["sslkey"] = ""
 		if err != nil {
 			return err
 		}
@@ -157,8 +151,6 @@ func sslCertificateAuthority(tlsConf *tls.Config, o values) error {
 
 		var cert []byte
 		if sslinline == "true" {
-			// // Clear out this param, in case it were to be sent to the PostgreSQL server by mistake
-			o["sslrootcert"] = ""
 			cert = []byte(sslrootcert)
 		} else {
 			var err error