60 lines
1.5 KiB
Go
60 lines
1.5 KiB
Go
// Copyright 2014 The Go Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style
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// license that can be found in the LICENSE file.
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package icmp
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import (
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"golang.org/x/net/internal/iana"
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"golang.org/x/net/ipv4"
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"golang.org/x/net/ipv6"
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)
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// A DstUnreach represents an ICMP destination unreachable message
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// body.
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type DstUnreach struct {
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Data []byte // data, known as original datagram field
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Extensions []Extension // extensions
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}
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// Len implements the Len method of MessageBody interface.
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func (p *DstUnreach) Len(proto int) int {
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if p == nil {
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return 0
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}
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l, _ := multipartMessageBodyDataLen(proto, true, p.Data, p.Extensions)
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return l
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}
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// Marshal implements the Marshal method of MessageBody interface.
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func (p *DstUnreach) Marshal(proto int) ([]byte, error) {
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var typ Type
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switch proto {
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case iana.ProtocolICMP:
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typ = ipv4.ICMPTypeDestinationUnreachable
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case iana.ProtocolIPv6ICMP:
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typ = ipv6.ICMPTypeDestinationUnreachable
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default:
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return nil, errInvalidProtocol
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}
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if !validExtensions(typ, p.Extensions) {
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return nil, errInvalidExtension
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}
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return marshalMultipartMessageBody(proto, true, p.Data, p.Extensions)
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}
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// parseDstUnreach parses b as an ICMP destination unreachable message
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// body.
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func parseDstUnreach(proto int, typ Type, b []byte) (MessageBody, error) {
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if len(b) < 4 {
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return nil, errMessageTooShort
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}
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p := &DstUnreach{}
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var err error
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p.Data, p.Extensions, err = parseMultipartMessageBody(proto, typ, b)
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if err != nil {
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return nil, err
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}
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return p, nil
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}
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