64 lines
2.0 KiB
Go
64 lines
2.0 KiB
Go
package ice
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import (
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"net"
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"github.com/google/uuid"
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"github.com/pion/logging"
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"github.com/pion/mdns"
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"golang.org/x/net/ipv4"
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)
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// MulticastDNSMode represents the different Multicast modes ICE can run in
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type MulticastDNSMode byte
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// MulticastDNSMode enum
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const (
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// MulticastDNSModeDisabled means remote mDNS candidates will be discarded, and local host candidates will use IPs
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MulticastDNSModeDisabled MulticastDNSMode = iota + 1
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// MulticastDNSModeQueryOnly means remote mDNS candidates will be accepted, and local host candidates will use IPs
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MulticastDNSModeQueryOnly
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// MulticastDNSModeQueryAndGather means remote mDNS candidates will be accepted, and local host candidates will use mDNS
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MulticastDNSModeQueryAndGather
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)
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func generateMulticastDNSName() (string, error) {
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// https://tools.ietf.org/id/draft-ietf-rtcweb-mdns-ice-candidates-02.html#gathering
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// The unique name MUST consist of a version 4 UUID as defined in [RFC4122], followed by “.local”.
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u, err := uuid.NewRandom()
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return u.String() + ".local", err
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}
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func createMulticastDNS(mDNSMode MulticastDNSMode, mDNSName string, log logging.LeveledLogger) (*mdns.Conn, MulticastDNSMode, error) {
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if mDNSMode == MulticastDNSModeDisabled {
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return nil, mDNSMode, nil
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}
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addr, mdnsErr := net.ResolveUDPAddr("udp4", mdns.DefaultAddress)
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if mdnsErr != nil {
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return nil, mDNSMode, mdnsErr
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}
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l, mdnsErr := net.ListenUDP("udp4", addr)
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if mdnsErr != nil {
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// If ICE fails to start MulticastDNS server just warn the user and continue
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log.Errorf("Failed to enable mDNS, continuing in mDNS disabled mode: (%s)", mdnsErr)
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return nil, MulticastDNSModeDisabled, nil
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}
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switch mDNSMode {
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case MulticastDNSModeQueryOnly:
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conn, err := mdns.Server(ipv4.NewPacketConn(l), &mdns.Config{})
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return conn, mDNSMode, err
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case MulticastDNSModeQueryAndGather:
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conn, err := mdns.Server(ipv4.NewPacketConn(l), &mdns.Config{
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LocalNames: []string{mDNSName},
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})
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return conn, mDNSMode, err
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default:
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return nil, mDNSMode, nil
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}
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}
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