package discover

import "github.com/ethereum/go-ethereum/p2p/discover"

Package discover implements the Node Discovery Protocol.

The Node Discovery protocol provides a way to find RLPx nodes that can be connected to. It uses a Kademlia-like protocol to maintain a distributed database of the IDs and endpoints of all listening nodes.

Index ¶

• type Config
• type ReadPacket
• type Table
• func (tab *Table) ReadRandomNodes(buf []*enode.Node) (n int)
• type UDPConn
• type UDPv4
• func ListenUDP(c UDPConn, ln *enode.LocalNode, cfg Config) (*UDPv4, error)
• func ListenV4(c UDPConn, ln *enode.LocalNode, cfg Config) (*UDPv4, error)
• func (t *UDPv4) Close()
• func (t *UDPv4) LookupPubkey(key *ecdsa.PublicKey) []*enode.Node
• func (t *UDPv4) Ping(n *enode.Node) error
• func (t *UDPv4) RandomNodes() enode.Iterator
• func (t *UDPv4) RequestENR(n *enode.Node) (*enode.Node, error)
• func (t *UDPv4) Resolve(n *enode.Node) *enode.Node
• func (t *UDPv4) Self() *enode.Node

Package Files ¶

common.go lookup.go node.go ntp.go table.go v4_udp.go

type Config ¶ Uses

type Config struct {
    // These settings are required and configure the UDP listener:
    PrivateKey *ecdsa.PrivateKey

    // These settings are optional:
    NetRestrict *netutil.Netlist  // network whitelist
    Bootnodes   []*enode.Node     // list of bootstrap nodes
    Unhandled   chan<- ReadPacket // unhandled packets are sent on this channel
    Log         log.Logger        // if set, log messages go here
}

Config holds settings for the discovery listener.

type ReadPacket ¶ Uses

type ReadPacket struct {
    Data []byte
    Addr *net.UDPAddr
}

ReadPacket is a packet that couldn't be handled. Those packets are sent to the unhandled channel if configured. This is exported for internal use, do not use this type.

type Table ¶ Uses

type Table struct {
    // contains filtered or unexported fields
}

Table is the 'node table', a Kademlia-like index of neighbor nodes. The table keeps itself up-to-date by verifying the liveness of neighbors and requesting their node records when announcements of a new record version are received.

func (*Table) ReadRandomNodes ¶ Uses

func (tab *Table) ReadRandomNodes(buf []*enode.Node) (n int)

ReadRandomNodes fills the given slice with random nodes from the table. The results are guaranteed to be unique for a single invocation, no node will appear twice.

type UDPConn ¶ Uses

type UDPConn interface {
    ReadFromUDP(b []byte) (n int, addr *net.UDPAddr, err error)
    WriteToUDP(b []byte, addr *net.UDPAddr) (n int, err error)
    Close() error
    LocalAddr() net.Addr
}

UDPConn is a network connection on which discovery can operate.

type UDPv4 ¶ Uses

type UDPv4 struct {
    // contains filtered or unexported fields
}

UDPv4 implements the v4 wire protocol.

func ListenUDP ¶ Uses

func ListenUDP(c UDPConn, ln *enode.LocalNode, cfg Config) (*UDPv4, error)

ListenUDP starts listening for discovery packets on the given UDP socket.

func ListenV4 ¶ Uses

func ListenV4(c UDPConn, ln *enode.LocalNode, cfg Config) (*UDPv4, error)

func (*UDPv4) Close ¶ Uses

func (t *UDPv4) Close()

Close shuts down the socket and aborts any running queries.

func (*UDPv4) LookupPubkey ¶ Uses

func (t *UDPv4) LookupPubkey(key *ecdsa.PublicKey) []*enode.Node

LookupPubkey finds the closest nodes to the given public key.

func (*UDPv4) Ping ¶ Uses

func (t *UDPv4) Ping(n *enode.Node) error

Ping sends a ping message to the given node.

func (*UDPv4) RandomNodes ¶ Uses

func (t *UDPv4) RandomNodes() enode.Iterator

RandomNodes is an iterator yielding nodes from a random walk of the DHT.

func (*UDPv4) RequestENR ¶ Uses

func (t *UDPv4) RequestENR(n *enode.Node) (*enode.Node, error)

RequestENR sends enrRequest to the given node and waits for a response.

func (*UDPv4) Resolve ¶ Uses

func (t *UDPv4) Resolve(n *enode.Node) *enode.Node

Resolve searches for a specific node with the given ID and tries to get the most recent version of the node record for it. It returns n if the node could not be resolved.

func (*UDPv4) Self ¶ Uses

func (t *UDPv4) Self() *enode.Node

Self returns the local node.