status-go/vendor/github.com/pion/sctp/param_zero_checksum.go

57 lines
1.6 KiB
Go

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