57 lines
1.6 KiB
Go
57 lines
1.6 KiB
Go
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// SPDX-FileCopyrightText: 2023 The Pion community <https://pion.ly>
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// SPDX-License-Identifier: MIT
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package sctp
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import (
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"encoding/binary"
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"errors"
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)
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// This parameter is used to inform the receiver that a sender is willing to
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// accept zero as checksum if some other error detection method is used
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// instead.
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//
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// 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
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// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
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// | Type = 0x8001 (suggested) | Length = 8 |
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// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
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// | Error Detection Method Identifier (EDMID) |
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// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
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type paramZeroChecksumAcceptable struct {
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paramHeader
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// The Error Detection Method Identifier (EDMID) specifies an alternate
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// error detection method the sender of this parameter is willing to use for
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// received packets.
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edmid uint32
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}
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// Zero Checksum parameter error
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var (
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ErrZeroChecksumParamTooShort = errors.New("zero checksum parameter too short")
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)
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const (
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dtlsErrorDetectionMethod uint32 = 1
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)
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func (r *paramZeroChecksumAcceptable) marshal() ([]byte, error) {
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r.typ = zeroChecksumAcceptable
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r.raw = make([]byte, 4)
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binary.BigEndian.PutUint32(r.raw, r.edmid)
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return r.paramHeader.marshal()
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}
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func (r *paramZeroChecksumAcceptable) unmarshal(raw []byte) (param, error) {
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err := r.paramHeader.unmarshal(raw)
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if err != nil {
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return nil, err
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}
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if len(r.raw) < 4 {
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return nil, ErrZeroChecksumParamTooShort
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}
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r.edmid = binary.BigEndian.Uint32(r.raw)
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return r, nil
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}
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