73 lines
1.7 KiB
Go
73 lines
1.7 KiB
Go
// SPDX-FileCopyrightText: 2023 The Pion community <https://pion.ly>
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// SPDX-License-Identifier: MIT
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package proto
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import (
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"strconv"
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"github.com/pion/stun"
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)
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// Protocol is IANA assigned protocol number.
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type Protocol byte
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const (
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// ProtoTCP is IANA assigned protocol number for TCP.
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ProtoTCP Protocol = 6
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// ProtoUDP is IANA assigned protocol number for UDP.
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ProtoUDP Protocol = 17
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)
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func (p Protocol) String() string {
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switch p {
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case ProtoTCP:
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return "TCP"
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case ProtoUDP:
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return "UDP"
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default:
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return strconv.Itoa(int(p))
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}
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}
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// RequestedTransport represents REQUESTED-TRANSPORT attribute.
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//
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// This attribute is used by the client to request a specific transport
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// protocol for the allocated transport address. RFC 5766 only allows the use of
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// code point 17 (User Datagram Protocol).
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//
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// RFC 5766 Section 14.7
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type RequestedTransport struct {
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Protocol Protocol
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}
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func (t RequestedTransport) String() string {
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return "protocol: " + t.Protocol.String()
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}
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const requestedTransportSize = 4
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// AddTo adds REQUESTED-TRANSPORT to message.
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func (t RequestedTransport) AddTo(m *stun.Message) error {
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v := make([]byte, requestedTransportSize)
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v[0] = byte(t.Protocol)
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// b[1:4] is RFFU = 0.
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// The RFFU field MUST be set to zero on transmission and MUST be
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// ignored on reception. It is reserved for future uses.
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m.Add(stun.AttrRequestedTransport, v)
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return nil
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}
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// GetFrom decodes REQUESTED-TRANSPORT from message.
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func (t *RequestedTransport) GetFrom(m *stun.Message) error {
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v, err := m.Get(stun.AttrRequestedTransport)
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if err != nil {
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return err
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}
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if err = stun.CheckSize(stun.AttrRequestedTransport, len(v), requestedTransportSize); err != nil {
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return err
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}
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t.Protocol = Protocol(v[0])
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return nil
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}
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