61 lines
1.7 KiB
Go
61 lines
1.7 KiB
Go
|
// Copyright 2014 The Go Authors. All rights reserved.
|
||
|
|
// Use of this source code is governed by a BSD-style
|
||
|
|
// license that can be found in the LICENSE file.
|
||
|
|
|
||
|
|
package icmp
|
||
|
|
|
||
|
|
import "golang.org/x/net/internal/iana"
|
||
|
|
|
||
|
|
// A ParamProb represents an ICMP parameter problem message body.
|
||
|
|
type ParamProb struct {
|
||
|
|
Pointer uintptr // offset within the data where the error was detected
|
||
|
|
Data []byte // data, known as original datagram field
|
||
|
|
Extensions []Extension // extensions
|
||
|
|
}
|
||
|
|
|
||
|
|
// Len implements the Len method of MessageBody interface.
|
||
|
|
func (p *ParamProb) Len(proto int) int {
|
||
|
|
if p == nil {
|
||
|
|
return 0
|
||
|
|
}
|
||
|
|
l, _ := multipartMessageBodyDataLen(proto, p.Data, p.Extensions)
|
||
|
|
return 4 + l
|
||
|
|
}
|
||
|
|
|
||
|
|
// Marshal implements the Marshal method of MessageBody interface.
|
||
|
|
func (p *ParamProb) Marshal(proto int) ([]byte, error) {
|
||
|
|
if proto == iana.ProtocolIPv6ICMP {
|
||
|
|
b := make([]byte, p.Len(proto))
|
||
|
|
b[0], b[1], b[2], b[3] = byte(p.Pointer>>24), byte(p.Pointer>>16), byte(p.Pointer>>8), byte(p.Pointer)
|
||
|
|
copy(b[4:], p.Data)
|
||
|
|
return b, nil
|
||
|
|
}
|
||
|
|
b, err := marshalMultipartMessageBody(proto, p.Data, p.Extensions)
|
||
|
|
if err != nil {
|
||
|
|
return nil, err
|
||
|
|
}
|
||
|
|
b[0] = byte(p.Pointer)
|
||
|
|
return b, nil
|
||
|
|
}
|
||
|
|
|
||
|
|
// parseParamProb parses b as an ICMP parameter problem message body.
|
||
|
|
func parseParamProb(proto int, b []byte) (MessageBody, error) {
|
||
|
|
if len(b) < 4 {
|
||
|
|
return nil, errMessageTooShort
|
||
|
|
}
|
||
|
|
p := &ParamProb{}
|
||
|
|
if proto == iana.ProtocolIPv6ICMP {
|
||
|
|
p.Pointer = uintptr(b[0])<<24 | uintptr(b[1])<<16 | uintptr(b[2])<<8 | uintptr(b[3])
|
||
|
|
p.Data = make([]byte, len(b)-4)
|
||
|
|
copy(p.Data, b[4:])
|
||
|
|
return p, nil
|
||
|
|
}
|
||
|
|
p.Pointer = uintptr(b[0])
|
||
|
|
var err error
|
||
|
|
p.Data, p.Extensions, err = parseMultipartMessageBody(proto, b)
|
||
|
|
if err != nil {
|
||
|
|
return nil, err
|
||
|
|
}
|
||
|
|
return p, nil
|
||
|
|
}
|