accept.go

/*
 * Copyright 2019 The CovenantSQL Authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package rpc

import (
	"context"
	"net"

	"github.com/CovenantSQL/CovenantSQL/crypto/etls"
	"github.com/CovenantSQL/CovenantSQL/utils/log"
)

// AcceptRawConn accepts raw connection without encryption or node-oriented mechanism.
//
// Corresponding dialer is net.Dial.
func AcceptRawConn(ctx context.Context, conn net.Conn) (net.Conn, error) {
	// TODO(leventeliu): pass context.
	return conn, nil
}

// NewAcceptCryptoConnFunc returns a AcceptConn function which accepts raw connection and uses the
// cipher handler to handle it as etls.CryptoConn.
//
// Corresponding dialer is crypto/etls.Dial.
func NewAcceptCryptoConnFunc(handler etls.CipherHandler) AcceptConn {
	return func(ctx context.Context, conn net.Conn) (net.Conn, error) {
		cryptoConn, err := handler(conn)
		if err != nil {
			_ = conn.Close()
			return nil, err
		}
		return cryptoConn, nil
	}
}

// AcceptNAConn accepts connection as a naconn.NAConn.
//
// Default accept function of RPC server, and also the only accept function for
// the connections from a NAConnPool.
//
// Corresponding dialer is naconn.Dial/naconn.DialEx.
func AcceptNAConn(ctx context.Context, conn net.Conn) (net.Conn, error) {
	naconn, err := Accept(conn)
	if err != nil {
		log.WithFields(log.Fields{
			"local":  conn.LocalAddr(),
			"remote": conn.RemoteAddr(),
		}).WithError(err).Error("failed to accept NAConn")
		_ = conn.Close()
		return nil, err
	}
	return naconn, nil
}