Documentation
¶
Overview ¶
Package icmp provides basic functions for the manipulation of messages used in the Internet Control Message Protocols, ICMPv4 and ICMPv6.
ICMPv4 and ICMPv6 are defined in RFC 792 and RFC 4443. Multi-part message support for ICMP is defined in RFC 4884. ICMP extensions for MPLS are defined in RFC 4950. ICMP extensions for interface and next-hop identification are defined in RFC 5837. PROBE: A utility for probing interfaces is defined in RFC 8335.
Index ¶
- Constants
- Variables
- func IPv6PseudoHeader(src, dst net.IP) []byte
- func ParseIPv4Header(b []byte) (*ipv4.Header, error)
- type DefaultMessageBodydeprecated
- type DstUnreach
- type Echo
- type ExtendedEchoReply
- type ExtendedEchoRequest
- type Extension
- type InterfaceIdent
- type InterfaceInfo
- type MPLSLabel
- type MPLSLabelStack
- type Message
- type MessageBody
- type PacketConn
- func (c *PacketConn) Close() error
- func (c *PacketConn) IPv4PacketConn() *ipv4.PacketConn
- func (c *PacketConn) IPv6PacketConn() *ipv6.PacketConn
- func (c *PacketConn) LocalAddr() net.Addr
- func (c *PacketConn) ReadFrom(b []byte) (int, net.Addr, error)
- func (c *PacketConn) SetDeadline(t time.Time) error
- func (c *PacketConn) SetReadDeadline(t time.Time) error
- func (c *PacketConn) SetWriteDeadline(t time.Time) error
- func (c *PacketConn) WriteTo(b []byte, dst net.Addr) (int, error)
- type PacketTooBig
- type ParamProb
- type RawBody
- type RawExtension
- type TimeExceeded
- type Timestamp
- type Type
- Bugs
Examples ¶
Constants ¶
const ( ProtocolIP = 0 // IPv4 encapsulation, pseudo protocol number ProtocolHOPOPT = 0 // IPv6 Hop-by-Hop Option ProtocolICMP = 1 // Internet Control Message ProtocolIGMP = 2 // Internet Group Management ProtocolGGP = 3 // Gateway-to-Gateway ProtocolIPv4 = 4 // IPv4 encapsulation ProtocolST = 5 // Stream ProtocolTCP = 6 // Transmission Control ProtocolCBT = 7 // CBT ProtocolEGP = 8 // Exterior Gateway Protocol ProtocolIGP = 9 // any private interior gateway (used by Cisco for their IGRP) ProtocolBBNRCCMON = 10 // BBN RCC Monitoring ProtocolNVPII = 11 // Network Voice Protocol ProtocolPUP = 12 // PUP ProtocolEMCON = 14 // EMCON ProtocolXNET = 15 // Cross Net Debugger ProtocolCHAOS = 16 // Chaos ProtocolUDP = 17 // User Datagram ProtocolMUX = 18 // Multiplexing ProtocolDCNMEAS = 19 // DCN Measurement Subsystems ProtocolHMP = 20 // Host Monitoring ProtocolPRM = 21 // Packet Radio Measurement ProtocolXNSIDP = 22 // XEROX NS IDP ProtocolTRUNK1 = 23 // Trunk-1 ProtocolTRUNK2 = 24 // Trunk-2 ProtocolLEAF1 = 25 // Leaf-1 ProtocolLEAF2 = 26 // Leaf-2 ProtocolRDP = 27 // Reliable Data Protocol ProtocolIRTP = 28 // Internet Reliable Transaction ProtocolISOTP4 = 29 // ISO Transport Protocol Class 4 ProtocolNETBLT = 30 // Bulk Data Transfer Protocol ProtocolMFENSP = 31 // MFE Network Services Protocol ProtocolMERITINP = 32 // MERIT Internodal Protocol ProtocolDCCP = 33 // Datagram Congestion Control Protocol Protocol3PC = 34 // Third Party Connect Protocol ProtocolIDPR = 35 // Inter-Domain Policy Routing Protocol ProtocolXTP = 36 // XTP ProtocolDDP = 37 // Datagram Delivery Protocol ProtocolIDPRCMTP = 38 // IDPR Control Message Transport Proto ProtocolTPPP = 39 // TP++ Transport Protocol ProtocolIL = 40 // IL Transport Protocol ProtocolIPv6 = 41 // IPv6 encapsulation ProtocolSDRP = 42 // Source Demand Routing Protocol ProtocolIPv6Route = 43 // Routing Header for IPv6 ProtocolIPv6Frag = 44 // Fragment Header for IPv6 ProtocolIDRP = 45 // Inter-Domain Routing Protocol ProtocolRSVP = 46 // Reservation Protocol ProtocolGRE = 47 // Generic Routing Encapsulation ProtocolDSR = 48 // Dynamic Source Routing Protocol ProtocolBNA = 49 // BNA ProtocolESP = 50 // Encap Security Payload ProtocolAH = 51 // Authentication Header ProtocolINLSP = 52 // Integrated Net Layer Security TUBA ProtocolNARP = 54 // NBMA Address Resolution Protocol ProtocolMOBILE = 55 // IP Mobility ProtocolTLSP = 56 // Transport Layer Security Protocol using Kryptonet key management ProtocolSKIP = 57 // SKIP ProtocolIPv6ICMP = 58 // ICMP for IPv6 ProtocolIPv6NoNxt = 59 // No Next Header for IPv6 ProtocolIPv6Opts = 60 // Destination Options for IPv6 ProtocolCFTP = 62 // CFTP ProtocolSATEXPAK = 64 // SATNET and Backroom EXPAK ProtocolKRYPTOLAN = 65 // Kryptolan ProtocolRVD = 66 // MIT Remote Virtual Disk Protocol ProtocolIPPC = 67 // Internet Pluribus Packet Core ProtocolSATMON = 69 // SATNET Monitoring ProtocolVISA = 70 // VISA Protocol ProtocolIPCV = 71 // Internet Packet Core Utility ProtocolCPNX = 72 // Computer Protocol Network Executive ProtocolCPHB = 73 // Computer Protocol Heart Beat ProtocolWSN = 74 // Wang Span Network ProtocolPVP = 75 // Packet Video Protocol ProtocolBRSATMON = 76 // Backroom SATNET Monitoring ProtocolSUNND = 77 // SUN ND PROTOCOL-Temporary ProtocolWBMON = 78 // WIDEBAND Monitoring ProtocolWBEXPAK = 79 // WIDEBAND EXPAK ProtocolISOIP = 80 // ISO Internet Protocol ProtocolVMTP = 81 // VMTP ProtocolSECUREVMTP = 82 // SECURE-VMTP ProtocolVINES = 83 // VINES ProtocolTTP = 84 // Transaction Transport Protocol ProtocolIPTM = 84 // Internet Protocol Traffic Manager ProtocolNSFNETIGP = 85 // NSFNET-IGP ProtocolDGP = 86 // Dissimilar Gateway Protocol ProtocolTCF = 87 // TCF ProtocolEIGRP = 88 // EIGRP ProtocolOSPFIGP = 89 // OSPFIGP ProtocolSpriteRPC = 90 // Sprite RPC Protocol ProtocolLARP = 91 // Locus Address Resolution Protocol ProtocolMTP = 92 // Multicast Transport Protocol ProtocolAX25 = 93 // AX.25 Frames ProtocolIPIP = 94 // IP-within-IP Encapsulation Protocol ProtocolSCCSP = 96 // Semaphore Communications Sec. Pro. ProtocolETHERIP = 97 // Ethernet-within-IP Encapsulation ProtocolENCAP = 98 // Encapsulation Header ProtocolGMTP = 100 // GMTP ProtocolIFMP = 101 // Ipsilon Flow Management Protocol ProtocolPNNI = 102 // PNNI over IP ProtocolPIM = 103 // Protocol Independent Multicast ProtocolARIS = 104 // ARIS ProtocolSCPS = 105 // SCPS ProtocolQNX = 106 // QNX ProtocolAN = 107 // Active Networks ProtocolIPComp = 108 // IP Payload Compression Protocol ProtocolSNP = 109 // Sitara Networks Protocol ProtocolCompaqPeer = 110 // Compaq Peer Protocol ProtocolIPXinIP = 111 // IPX in IP ProtocolVRRP = 112 // Virtual Router Redundancy Protocol ProtocolPGM = 113 // PGM Reliable Transport Protocol ProtocolL2TP = 115 // Layer Two Tunneling Protocol ProtocolDDX = 116 // D-II Data Exchange (DDX) ProtocolIATP = 117 // Interactive Agent Transfer Protocol ProtocolSTP = 118 // Schedule Transfer Protocol ProtocolSRP = 119 // SpectraLink Radio Protocol ProtocolUTI = 120 // UTI ProtocolSMP = 121 // Simple Message Protocol ProtocolPTP = 123 // Performance Transparency Protocol ProtocolISIS = 124 // ISIS over IPv4 ProtocolFIRE = 125 // FIRE ProtocolCRTP = 126 // Combat Radio Transport Protocol ProtocolCRUDP = 127 // Combat Radio User Datagram ProtocolSSCOPMCE = 128 // SSCOPMCE ProtocolIPLT = 129 // IPLT ProtocolSPS = 130 // Secure Packet Shield ProtocolPIPE = 131 // Private IP Encapsulation within IP ProtocolSCTP = 132 // Stream Control Transmission Protocol ProtocolFC = 133 // Fibre Channel ProtocolRSVPE2EIGNORE = 134 // RSVP-E2E-IGNORE ProtocolMobilityHeader = 135 // Mobility Header ProtocolUDPLite = 136 // UDPLite ProtocolMPLSinIP = 137 // MPLS-in-IP ProtocolMANET = 138 // MANET Protocols ProtocolHIP = 139 // Host Identity Protocol ProtocolShim6 = 140 // Shim6 Protocol ProtocolWESP = 141 // Wrapped Encapsulating Security Payload ProtocolROHC = 142 // Robust Header Compression ProtocolReserved = 255 // Reserved )
const ( AddrFamilyIPv4 = 1 // IP (IP version 4) AddrFamilyIPv6 = 2 // IP6 (IP version 6) AddrFamilyNSAP = 3 // NSAP AddrFamilyHDLC = 4 // HDLC (8-bit multidrop) AddrFamilyBBN1822 = 5 // BBN 1822 AddrFamily802 = 6 // 802 (includes all 802 media plus Ethernet "canonical format") AddrFamilyE163 = 7 // E.163 AddrFamilyE164 = 8 // E.164 (SMDS, Frame Relay, ATM) AddrFamilyF69 = 9 // F.69 (Telex) AddrFamilyX121 = 10 // X.121 (X.25, Frame Relay) AddrFamilyIPX = 11 // IPX AddrFamilyAppletalk = 12 // Appletalk AddrFamilyDecnetIV = 13 // Decnet IV AddrFamilyBanyanVines = 14 // Banyan Vines AddrFamilyE164withSubaddress = 15 // E.164 with NSAP format subaddress AddrFamilyDNS = 16 // DNS (Domain Name System) AddrFamilyDistinguishedName = 17 // Distinguished Name AddrFamilyASNumber = 18 // AS Number AddrFamilyXTPoverIPv4 = 19 // XTP over IP version 4 AddrFamilyXTPoverIPv6 = 20 // XTP over IP version 6 AddrFamilyXTPnativemodeXTP = 21 // XTP native mode XTP AddrFamilyFibreChannelWorldWidePortName = 22 // Fibre Channel World-Wide Port Name AddrFamilyFibreChannelWorldWideNodeName = 23 // Fibre Channel World-Wide Node Name AddrFamilyGWID = 24 // GWID AddrFamilyL2VPN = 25 // AFI for L2VPN information AddrFamilyMPLSTPSectionEndpointID = 26 // MPLS-TP Section Endpoint Identifier AddrFamilyMPLSTPLSPEndpointID = 27 // MPLS-TP LSP Endpoint Identifier AddrFamilyMPLSTPPseudowireEndpointID = 28 // MPLS-TP Pseudowire Endpoint Identifier AddrFamilyMTIPv4 = 29 // MT IP: Multi-Topology IP version 4 AddrFamilyMTIPv6 = 30 // MT IPv6: Multi-Topology IP version 6 AddrFamilyEIGRPCommonServiceFamily = 16384 // EIGRP Common Service Family AddrFamilyEIGRPIPv4ServiceFamily = 16385 // EIGRP IPv4 Service Family AddrFamilyEIGRPIPv6ServiceFamily = 16386 // EIGRP IPv6 Service Family AddrFamilyLISPCanonicalAddressFormat = 16387 // LISP Canonical Address Format (LCAF) AddrFamilyBGPLS = 16388 // BGP-LS AddrFamily48bitMAC = 16389 // 48-bit MAC AddrFamily64bitMAC = 16390 // 64-bit MAC AddrFamilyOUI = 16391 // OUI AddrFamilyMACFinal24bits = 16392 // MAC/24 AddrFamilyMACFinal40bits = 16393 // MAC/40 AddrFamilyIPv6Initial64bits = 16394 // IPv6/64 AddrFamilyRBridgePortID = 16395 // RBridge Port ID AddrFamilyTRILLNickname = 16396 // TRILL Nickname )
Variables ¶
var ( // NativeEndian is the machine native endian implementation of // ByteOrder. NativeEndian binary.ByteOrder )
Functions ¶
func IPv6PseudoHeader ¶
IPv6PseudoHeader returns an IPv6 pseudo header for checksum calculation.
func ParseIPv4Header ¶
ParseIPv4Header returns the IPv4 header of the IPv4 packet that triggered an ICMP error message. This is found in the Data field of the ICMP error message body.
The provided b must be in the format used by a raw ICMP socket on the local system. This may differ from the wire format, and the format used by a raw IP socket, depending on the system.
To parse an IPv6 header, use ipv6.ParseHeader.
Types ¶
type DefaultMessageBody
deprecated
type DefaultMessageBody = RawBody
A DefaultMessageBody represents the default message body.
Deprecated: Use RawBody instead.
type DstUnreach ¶
type DstUnreach struct {
Data []byte // data, known as original datagram field
Extensions []Extension // extensions
}
A DstUnreach represents an ICMP destination unreachable message body.
func (*DstUnreach) Len ¶
func (p *DstUnreach) Len(proto int) int
Len implements the Len method of MessageBody interface.
type Echo ¶
An Echo represents an ICMP echo request or reply message body.
type ExtendedEchoReply ¶
type ExtendedEchoReply struct {
ID int // identifier
Seq int // sequence number
State int // 3-bit state working together with Message.Code
Active bool // probed interface is active
IPv4 bool // probed interface runs IPv4
IPv6 bool // probed interface runs IPv6
}
An ExtendedEchoReply represents an ICMP extended echo reply message body.
func (*ExtendedEchoReply) Len ¶
func (p *ExtendedEchoReply) Len(proto int) int
Len implements the Len method of MessageBody interface.
type ExtendedEchoRequest ¶
type ExtendedEchoRequest struct {
ID int // identifier
Seq int // sequence number
Local bool // must be true when identifying by name or index
Extensions []Extension // extensions
}
An ExtendedEchoRequest represents an ICMP extended echo request message body.
func (*ExtendedEchoRequest) Len ¶
func (p *ExtendedEchoRequest) Len(proto int) int
Len implements the Len method of MessageBody interface.
type Extension ¶
type Extension interface {
// Len returns the length of ICMP extension.
// The provided proto must be either the ICMPv4 or ICMPv6
// protocol number.
Len(proto int) int
// Marshal returns the binary encoding of ICMP extension.
// The provided proto must be either the ICMPv4 or ICMPv6
// protocol number.
Marshal(proto int) ([]byte, error)
}
An Extension represents an ICMP extension.
type InterfaceIdent ¶
type InterfaceIdent struct {
Class int // extension object class number
Type int // extension object sub-type
Name string // interface name
Index int // interface index
AFI int // address family identifier; see address family numbers in IANA registry
Addr []byte // address
}
An InterfaceIdent represents interface identification.
func (*InterfaceIdent) Len ¶
func (ifi *InterfaceIdent) Len(_ int) int
Len implements the Len method of Extension interface.
type InterfaceInfo ¶
type InterfaceInfo struct {
Class int // extension object class number
Type int // extension object sub-type
Interface *net.Interface
Addr *net.IPAddr
}
An InterfaceInfo represents interface and next-hop identification.
func (*InterfaceInfo) Len ¶
func (ifi *InterfaceInfo) Len(proto int) int
Len implements the Len method of Extension interface.
type MPLSLabel ¶
type MPLSLabel struct {
Label int // label value
TC int // traffic class; formerly experimental use
S bool // bottom of stack
TTL int // time to live
}
MPLSLabel represents an MPLS label stack entry.
type MPLSLabelStack ¶
type MPLSLabelStack struct {
Class int // extension object class number
Type int // extension object sub-type
Labels []MPLSLabel
}
MPLSLabelStack represents an MPLS label stack.
func (*MPLSLabelStack) Len ¶
func (ls *MPLSLabelStack) Len(proto int) int
Len implements the Len method of Extension interface.
type Message ¶
type Message struct {
Type Type // type, either ipv4.ICMPType or ipv6.ICMPType
Code int // code
Checksum int // checksum
Body MessageBody // body
}
A Message represents an ICMP message.
func ParseMessage ¶
ParseMessage parses b as an ICMP message. The provided proto must be either the ICMPv4 or ICMPv6 protocol number.
func (*Message) Marshal ¶
Marshal returns the binary encoding of the ICMP message m.
For an ICMPv4 message, the returned message always contains the calculated checksum field.
For an ICMPv6 message, the returned message contains the calculated checksum field when psh is not nil, otherwise the kernel will compute the checksum field during the message transmission. When psh is not nil, it must be the pseudo header for IPv6.
type MessageBody ¶
type MessageBody interface {
// Len returns the length of ICMP message body.
// The provided proto must be either the ICMPv4 or ICMPv6
// protocol number.
Len(proto int) int
// Marshal returns the binary encoding of ICMP message body.
// The provided proto must be either the ICMPv4 or ICMPv6
// protocol number.
Marshal(proto int) ([]byte, error)
}
A MessageBody represents an ICMP message body.
type PacketConn ¶
type PacketConn struct {
// contains filtered or unexported fields
}
A PacketConn represents a packet network endpoint that uses either ICMPv4 or ICMPv6.
Example (NonPrivilegedPing) ¶
package main
import (
"log"
"net"
"os"
"runtime"
"golang.org/x/net/icmp"
"golang.org/x/net/ipv6"
)
func main() {
switch runtime.GOOS {
case "darwin":
case "linux":
log.Println("you may need to adjust the net.ipv4.ping_group_range kernel state")
default:
log.Println("not supported on", runtime.GOOS)
return
}
c, err := icmp.ListenPacket("udp6", "fe80::1%en0")
if err != nil {
log.Fatal(err)
}
defer c.Close()
wm := icmp.Message{
Type: ipv6.ICMPTypeEchoRequest, Code: 0,
Body: &icmp.Echo{
ID: os.Getpid() & 0xffff, Seq: 1,
Data: []byte("HELLO-R-U-THERE"),
},
}
wb, err := wm.Marshal(nil)
if err != nil {
log.Fatal(err)
}
if _, err := c.WriteTo(wb, &net.UDPAddr{IP: net.ParseIP("ff02::1"), Zone: "en0"}); err != nil {
log.Fatal(err)
}
rb := make([]byte, 1500)
n, peer, err := c.ReadFrom(rb)
if err != nil {
log.Fatal(err)
}
rm, err := icmp.ParseMessage(58, rb[:n])
if err != nil {
log.Fatal(err)
}
switch rm.Type {
case ipv6.ICMPTypeEchoReply:
log.Printf("got reflection from %v", peer)
default:
log.Printf("got %+v; want echo reply", rm)
}
}
Output:
func ListenPacket ¶
func ListenPacket(network, address string) (*PacketConn, error)
ListenPacket listens for incoming ICMP packets addressed to address. See net.Dial for the syntax of address.
For non-privileged datagram-oriented ICMP endpoints, network must be "udp4" or "udp6". The endpoint allows to read, write a few limited ICMP messages such as echo request and echo reply. Currently only Darwin and Linux support this.
Examples:
ListenPacket("udp4", "192.168.0.1")
ListenPacket("udp4", "0.0.0.0")
ListenPacket("udp6", "fe80::1%en0")
ListenPacket("udp6", "::")
For privileged raw ICMP endpoints, network must be "ip4" or "ip6" followed by a colon and an ICMP protocol number or name.
Examples:
ListenPacket("ip4:icmp", "192.168.0.1")
ListenPacket("ip4:1", "0.0.0.0")
ListenPacket("ip6:ipv6-icmp", "fe80::1%en0")
ListenPacket("ip6:58", "::")
func (*PacketConn) IPv4PacketConn ¶
func (c *PacketConn) IPv4PacketConn() *ipv4.PacketConn
IPv4PacketConn returns the ipv4.PacketConn of c. It returns nil when c is not created as the endpoint for ICMPv4.
func (*PacketConn) IPv6PacketConn ¶
func (c *PacketConn) IPv6PacketConn() *ipv6.PacketConn
IPv6PacketConn returns the ipv6.PacketConn of c. It returns nil when c is not created as the endpoint for ICMPv6.
func (*PacketConn) LocalAddr ¶
func (c *PacketConn) LocalAddr() net.Addr
LocalAddr returns the local network address.
func (*PacketConn) SetDeadline ¶
func (c *PacketConn) SetDeadline(t time.Time) error
SetDeadline sets the read and write deadlines associated with the endpoint.
func (*PacketConn) SetReadDeadline ¶
func (c *PacketConn) SetReadDeadline(t time.Time) error
SetReadDeadline sets the read deadline associated with the endpoint.
func (*PacketConn) SetWriteDeadline ¶
func (c *PacketConn) SetWriteDeadline(t time.Time) error
SetWriteDeadline sets the write deadline associated with the endpoint.
type PacketTooBig ¶
type PacketTooBig struct {
MTU int // maximum transmission unit of the nexthop link
Data []byte // data, known as original datagram field
}
A PacketTooBig represents an ICMP packet too big message body.
func (*PacketTooBig) Len ¶
func (p *PacketTooBig) Len(proto int) int
Len implements the Len method of MessageBody interface.
type ParamProb ¶
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
}
A ParamProb represents an ICMP parameter problem message body.
type RawBody ¶
type RawBody struct {
Data []byte // data
}
A RawBody represents a raw message body.
A raw message body is excluded from message processing and can be used to construct applications such as protocol conformance testing.
type RawExtension ¶
type RawExtension struct {
Data []byte // data
}
A RawExtension represents a raw extension.
A raw extension is excluded from message processing and can be used to construct applications such as protocol conformance testing.
func (*RawExtension) Len ¶
func (p *RawExtension) Len(proto int) int
Len implements the Len method of Extension interface.
type TimeExceeded ¶
type TimeExceeded struct {
Data []byte // data, known as original datagram field
Extensions []Extension // extensions
}
A TimeExceeded represents an ICMP time exceeded message body.
func (*TimeExceeded) Len ¶
func (p *TimeExceeded) Len(proto int) int
Len implements the Len method of MessageBody interface.
Notes ¶
Bugs ¶
This package is not implemented on JS, NaCl and Plan 9.
Source Files