github.com/openziti/transport@v0.1.5/dialer.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 transport 18 19 import ( 20 "fmt" 21 "github.com/pkg/errors" 22 "net" 23 "time" 24 ) 25 26 // Creates a dialer and sets the local ip used for dialing 27 // 28 func NewDialerWithLocalBinding(addressType string, timeout time.Duration, localBinding string) (*net.Dialer, error) { 29 30 dialer := &net.Dialer{ 31 Timeout: timeout, 32 } 33 34 if localBinding != "" { 35 iface, err := ResolveInterface(localBinding) 36 37 if err != nil { 38 return nil, err 39 } 40 41 addrs, err := iface.Addrs() 42 43 if err != nil { 44 return nil, err 45 } 46 47 if len(addrs) == 0 { 48 return nil, errors.New(fmt.Sprintf("no ip addresses assigned to interface %s", localBinding)) 49 } 50 51 switch addressType { 52 case "udp": 53 dialer.LocalAddr = &net.UDPAddr{ 54 IP: addrs[0].(*net.IPNet).IP, 55 } 56 case "tcp", "tls": 57 dialer.LocalAddr = &net.TCPAddr{ 58 IP: addrs[0].(*net.IPNet).IP, 59 } 60 default: 61 return nil, errors.New(fmt.Sprintf("Unsupported addressType: %s", addressType)) 62 } 63 } 64 65 return dialer, nil 66 }