switch to Go modules

vendor/golang.org/x/crypto/ssh/server.go

@@ -404,7 +404,7 @@ userAuthLoop:
 			perms, authErr = config.PasswordCallback(s, password)
 		case "keyboard-interactive":
 			if config.KeyboardInteractiveCallback == nil {
-				authErr = errors.New("ssh: keyboard-interactive auth not configubred")
+				authErr = errors.New("ssh: keyboard-interactive auth not configured")
 				break
 			}
 
@@ -484,6 +484,7 @@ userAuthLoop:
 				// sig.Format.  This is usually the same, but
 				// for certs, the names differ.
 				if !isAcceptableAlgo(sig.Format) {
+					authErr = fmt.Errorf("ssh: algorithm %q not accepted", sig.Format)
 					break
 				}
 				signedData := buildDataSignedForAuth(sessionID, userAuthReq, algoBytes, pubKeyData)