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Diffstat (limited to 'pkg/tcpip/header/icmpv4.go')
-rw-r--r-- | pkg/tcpip/header/icmpv4.go | 108 |
1 files changed, 108 insertions, 0 deletions
diff --git a/pkg/tcpip/header/icmpv4.go b/pkg/tcpip/header/icmpv4.go new file mode 100644 index 000000000..782e1053c --- /dev/null +++ b/pkg/tcpip/header/icmpv4.go @@ -0,0 +1,108 @@ +// Copyright 2018 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package header + +import ( + "encoding/binary" + + "gvisor.googlesource.com/gvisor/pkg/tcpip" +) + +// ICMPv4 represents an ICMPv4 header stored in a byte array. +type ICMPv4 []byte + +const ( + // ICMPv4MinimumSize is the minimum size of a valid ICMP packet. + ICMPv4MinimumSize = 4 + + // ICMPv4EchoMinimumSize is the minimum size of a valid ICMP echo packet. + ICMPv4EchoMinimumSize = 6 + + // ICMPv4DstUnreachableMinimumSize is the minimum size of a valid ICMP + // destination unreachable packet. + ICMPv4DstUnreachableMinimumSize = ICMPv4MinimumSize + 4 + + // ICMPv4ProtocolNumber is the ICMP transport protocol number. + ICMPv4ProtocolNumber tcpip.TransportProtocolNumber = 1 +) + +// ICMPv4Type is the ICMP type field described in RFC 792. +type ICMPv4Type byte + +// Typical values of ICMPv4Type defined in RFC 792. +const ( + ICMPv4EchoReply ICMPv4Type = 0 + ICMPv4DstUnreachable ICMPv4Type = 3 + ICMPv4SrcQuench ICMPv4Type = 4 + ICMPv4Redirect ICMPv4Type = 5 + ICMPv4Echo ICMPv4Type = 8 + ICMPv4TimeExceeded ICMPv4Type = 11 + ICMPv4ParamProblem ICMPv4Type = 12 + ICMPv4Timestamp ICMPv4Type = 13 + ICMPv4TimestampReply ICMPv4Type = 14 + ICMPv4InfoRequest ICMPv4Type = 15 + ICMPv4InfoReply ICMPv4Type = 16 +) + +// Values for ICMP code as defined in RFC 792. +const ( + ICMPv4PortUnreachable = 3 + ICMPv4FragmentationNeeded = 4 +) + +// Type is the ICMP type field. +func (b ICMPv4) Type() ICMPv4Type { return ICMPv4Type(b[0]) } + +// SetType sets the ICMP type field. +func (b ICMPv4) SetType(t ICMPv4Type) { b[0] = byte(t) } + +// Code is the ICMP code field. Its meaning depends on the value of Type. +func (b ICMPv4) Code() byte { return b[1] } + +// SetCode sets the ICMP code field. +func (b ICMPv4) SetCode(c byte) { b[1] = c } + +// Checksum is the ICMP checksum field. +func (b ICMPv4) Checksum() uint16 { + return binary.BigEndian.Uint16(b[2:]) +} + +// SetChecksum sets the ICMP checksum field. +func (b ICMPv4) SetChecksum(checksum uint16) { + binary.BigEndian.PutUint16(b[2:], checksum) +} + +// SourcePort implements Transport.SourcePort. +func (ICMPv4) SourcePort() uint16 { + return 0 +} + +// DestinationPort implements Transport.DestinationPort. +func (ICMPv4) DestinationPort() uint16 { + return 0 +} + +// SetSourcePort implements Transport.SetSourcePort. +func (ICMPv4) SetSourcePort(uint16) { +} + +// SetDestinationPort implements Transport.SetDestinationPort. +func (ICMPv4) SetDestinationPort(uint16) { +} + +// Payload implements Transport.Payload. +func (b ICMPv4) Payload() []byte { + return b[ICMPv4MinimumSize:] +} |