mirror of
https://github.com/soypat/lneto.git
synced 2026-08-15 04:13:44 +00:00
Pat Whittingslow
198db3789b
* begin adding dns pcap functionality * improve question formatting * work on capturing answers as well * finalize DNS printing * increase subfield limits * add FlagContainer type * prettier DNS printing
134 lines
3.3 KiB
Go
134 lines
3.3 KiB
Go
package icmpv4
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import (
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"encoding/binary"
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"github.com/soypat/lneto"
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)
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//go:generate stringer -type=Type,CodeDestinationUnreachable,CodeRedirect -linecomment -output stringers.go
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const (
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sizeHeader = 8
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)
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type Type uint8
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const (
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TypeEchoReply Type = 0 // echo reply
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TypeEcho Type = 8 // echo
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TypeDestinationUnreachable Type = 3 // destination unreachable
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TypeSourceQuench Type = 4 // source quench
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TypeRedirect Type = 5 // redirect
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TypeTimeExceeded Type = 11 // time exceeded
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TypeParameterProblem Type = 12 // parameter problem
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TypeTimestamp Type = 13 // timestamp
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TypeTimestampReply Type = 14 // timestamp reply
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TypeInfoRequest Type = 15 // information request
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TypeInfoRequestReply Type = 16 // information request reply
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)
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type CodeTimeExceeded uint8
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const (
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CodeExceededInTransit CodeTimeExceeded = iota // TTL exceeded
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CodeFragmentReassembly // fragment reassembly time exceeded
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)
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type CodeDestinationUnreachable uint8
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const (
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CodeNetUnreachable CodeDestinationUnreachable = iota // net unreachable
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CodeHostUnreachable // host unreachable
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CodeProtoUnreachable // protocol unreachable
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CodePortUnreachable // port unreachable
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CodeFragNeededAndDFSet // fragmentation needed and DF set
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CodeSourceRouteFailed // source route failed
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)
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type CodeRedirect uint8
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const (
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CodeRedirectForNetwork CodeRedirect = iota // redirect for network
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CodeRedirectForHost // redirect for host
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CodeRedirectForToSAndNetwork // redirect for ToS+network
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CodeRedirectToSAndHost // redirect for ToS+host
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)
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func NewFrame(buf []byte) (Frame, error) {
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if len(buf) < sizeHeader {
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return Frame{}, lneto.ErrTruncatedFrame
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}
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return Frame{buf: buf}, nil
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}
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type Frame struct {
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buf []byte
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}
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func (frm Frame) Type() Type { return Type(frm.buf[0]) }
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func (frm Frame) SetType(t Type) { frm.buf[0] = uint8(t) }
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func (frm Frame) Code() uint8 { return frm.buf[1] }
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func (frm Frame) SetCode(code uint8) { frm.buf[1] = code }
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// CRC returns the checksum field of the frame.
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func (frm Frame) CRC() uint16 {
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return binary.BigEndian.Uint16(frm.buf[2:4])
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}
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// SetCRC sets the checksum field of the frame.
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func (frm Frame) SetCRC(crc uint16) {
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binary.BigEndian.PutUint16(frm.buf[2:4], crc)
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}
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func (frm Frame) payload() []byte {
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return frm.buf[4:]
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}
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type FrameDestinationUnreachable struct {
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Frame
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}
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func (frm FrameDestinationUnreachable) Code() CodeDestinationUnreachable {
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return CodeDestinationUnreachable(frm.Frame.Code())
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}
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func (frm FrameDestinationUnreachable) SetCode(code CodeDestinationUnreachable) {
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frm.Frame.SetCode(uint8(code))
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}
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type FrameEcho struct {
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Frame
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}
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func (frm FrameEcho) Identifier() uint16 {
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return binary.BigEndian.Uint16(frm.buf[4:6])
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}
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func (frm FrameEcho) SetIdentifier(id uint16) {
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binary.BigEndian.PutUint16(frm.buf[4:6], id)
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}
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func (frm FrameEcho) SequenceNumber() uint16 {
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return binary.BigEndian.Uint16(frm.buf[6:8])
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}
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func (frm FrameEcho) SetSequenceNumber(seq uint16) {
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binary.BigEndian.PutUint16(frm.buf[6:8], seq)
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}
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func (frm FrameEcho) Data() []byte {
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return frm.buf[8:]
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}
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func (frm FrameEcho) RawData() []byte {
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return frm.buf
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}
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