github.com/openziti/transport@v0.1.5/udp/listener.go (about)

     1  /*
     2  	Copyright NetFoundry, Inc.
     3  
     4  	Licensed under the Apache License, Version 2.0 (the "License");
     5  	you may not use this file except in compliance with the License.
     6  	You may obtain a copy of the License at
     7  
     8  	https://www.apache.org/licenses/LICENSE-2.0
     9  
    10  	Unless required by applicable law or agreed to in writing, software
    11  	distributed under the License is distributed on an "AS IS" BASIS,
    12  	WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    13  	See the License for the specific language governing permissions and
    14  	limitations under the License.
    15  */
    16  
    17  package udp
    18  
    19  import (
    20  	"bufio"
    21  	"github.com/michaelquigley/pfxlog"
    22  	"github.com/openziti/foundation/identity/identity"
    23  	"github.com/openziti/transport"
    24  	udp2 "github.com/openziti/foundation/udp"
    25  	"github.com/sirupsen/logrus"
    26  	"io"
    27  	"math"
    28  	"net"
    29  )
    30  
    31  func Listen(bindAddress *net.UDPAddr, name string, i *identity.TokenId, incoming chan transport.Connection) (io.Closer, error) {
    32  	log := pfxlog.ContextLogger(name + "/udp:" + bindAddress.String())
    33  
    34  	listener, err := udp2.Listen("udp", bindAddress)
    35  	if err != nil {
    36  		return nil, err
    37  	}
    38  
    39  	go acceptLoop(log.Entry, name, listener, incoming)
    40  
    41  	return listener, nil
    42  }
    43  
    44  func acceptLoop(log *logrus.Entry, name string, listener net.Listener, incoming chan transport.Connection) {
    45  	defer log.Error("exited")
    46  
    47  	for {
    48  		socket, err := listener.Accept()
    49  		if err != nil {
    50  			if netErr, ok := err.(net.Error); ok && !netErr.Temporary() {
    51  				log.WithField("err", err).Error("accept failed. Failure not recoverable. Exiting listen loop")
    52  				return
    53  			}
    54  			log.WithField("err", err).Error("accept failed")
    55  		} else {
    56  			log.Info("new udp connection accepted")
    57  			connection := &Connection{
    58  				detail: &transport.ConnectionDetail{
    59  					Address: "udp:" + socket.RemoteAddr().String(),
    60  					InBound: true,
    61  					Name:    name,
    62  				},
    63  				socket: socket,
    64  				reader: bufio.NewReaderSize(socket, math.MaxUint16),
    65  			}
    66  			incoming <- connection
    67  		}
    68  	}
    69  }