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Constants

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Variables

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var ValidSchemes = enr.SchemeMap{
	"v4": V4ID{},
}

    List of known secure identity schemes.

    View Source
    var ValidSchemesForTesting = enr.SchemeMap{
    	"v4":   V4ID{},
    	"null": NullID{},
    }

    Functions

    func DistCmp

    func DistCmp(target, a, b ID) int

      DistCmp compares the distances a->target and b->target. Returns -1 if a is closer to target, 1 if b is closer to target and 0 if they are equal.

      func LogDist

      func LogDist(a, b ID) int

        LogDist returns the logarithmic distance between a and b, log2(a ^ b).

        func SignV4

        func SignV4(r *enr.Record, privkey *ecdsa.PrivateKey) error

          SignV4 signs a record using the v4 scheme.

          Types

          type DB

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

            DB is the node database, storing previously seen nodes and any collected metadata about them for QoS purposes.

            func OpenDB

            func OpenDB(path string) (*DB, error)

              OpenDB opens a node database for storing and retrieving infos about known peers in the network. If no path is given an in-memory, temporary database is constructed.

              func (*DB) Close

              func (db *DB) Close()

                close flushes and closes the database files.

                func (*DB) DeleteNode

                func (db *DB) DeleteNode(id ID)

                  DeleteNode deletes all information associated with a node.

                  func (*DB) FindFails

                  func (db *DB) FindFails(id ID, ip net.IP) int

                    FindFails retrieves the number of findnode failures since bonding.

                    func (*DB) FindFailsV5

                    func (db *DB) FindFailsV5(id ID, ip net.IP) int

                      FindFailsV5 retrieves the discv5 findnode failure counter.

                      func (*DB) LastPingReceived

                      func (db *DB) LastPingReceived(id ID, ip net.IP) time.Time

                        LastPingReceived retrieves the time of the last ping packet received from a remote node.

                        func (*DB) LastPongReceived

                        func (db *DB) LastPongReceived(id ID, ip net.IP) time.Time

                          LastPongReceived retrieves the time of the last successful pong from remote node.

                          func (*DB) Node

                          func (db *DB) Node(id ID) *Node

                            Node retrieves a node with a given id from the database.

                            func (*DB) NodeSeq

                            func (db *DB) NodeSeq(id ID) uint64

                              NodeSeq returns the stored record sequence number of the given node.

                              func (*DB) QuerySeeds

                              func (db *DB) QuerySeeds(n int, maxAge time.Duration) []*Node

                                QuerySeeds retrieves random nodes to be used as potential seed nodes for bootstrapping.

                                func (*DB) Resolve

                                func (db *DB) Resolve(n *Node) *Node

                                  Resolve returns the stored record of the node if it has a larger sequence number than n.

                                  func (*DB) UpdateFindFails

                                  func (db *DB) UpdateFindFails(id ID, ip net.IP, fails int) error

                                    UpdateFindFails updates the number of findnode failures since bonding.

                                    func (*DB) UpdateFindFailsV5

                                    func (db *DB) UpdateFindFailsV5(id ID, ip net.IP, fails int) error

                                      UpdateFindFailsV5 stores the discv5 findnode failure counter.

                                      func (*DB) UpdateLastPingReceived

                                      func (db *DB) UpdateLastPingReceived(id ID, ip net.IP, instance time.Time) error

                                        UpdateLastPingReceived updates the last time we tried contacting a remote node.

                                        func (*DB) UpdateLastPongReceived

                                        func (db *DB) UpdateLastPongReceived(id ID, ip net.IP, instance time.Time) error

                                          UpdateLastPongReceived updates the last pong time of a node.

                                          func (*DB) UpdateNode

                                          func (db *DB) UpdateNode(node *Node) error

                                            UpdateNode inserts - potentially overwriting - a node into the peer database.

                                            type FairMix

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

                                              FairMix aggregates multiple node iterators. The mixer itself is an iterator which ends only when Close is called. Source iterators added via AddSource are removed from the mix when they end.

                                              The distribution of nodes returned by Next is approximately fair, i.e. FairMix attempts to draw from all sources equally often. However, if a certain source is slow and doesn't return a node within the configured timeout, a node from any other source will be returned.

                                              It's safe to call AddSource and Close concurrently with Next.

                                              func NewFairMix

                                              func NewFairMix(timeout time.Duration) *FairMix

                                                NewFairMix creates a mixer.

                                                The timeout specifies how long the mixer will wait for the next fairly-chosen source before giving up and taking a node from any other source. A good way to set the timeout is deciding how long you'd want to wait for a node on average. Passing a negative timeout makes the mixer completely fair.

                                                func (*FairMix) AddSource

                                                func (m *FairMix) AddSource(it Iterator)

                                                  AddSource adds a source of nodes.

                                                  func (*FairMix) Close

                                                  func (m *FairMix) Close()

                                                    Close shuts down the mixer and all current sources. Calling this is required to release resources associated with the mixer.

                                                    func (*FairMix) Next

                                                    func (m *FairMix) Next() bool

                                                      Next returns a node from a random source.

                                                      func (*FairMix) Node

                                                      func (m *FairMix) Node() *Node

                                                        Node returns the current node.

                                                        type ID

                                                        type ID [32]byte

                                                          ID is a unique identifier for each node.

                                                          func HexID

                                                          func HexID(in string) ID

                                                            HexID converts a hex string to an ID. The string may be prefixed with 0x. It panics if the string is not a valid ID.

                                                            func ParseID

                                                            func ParseID(in string) (ID, error)

                                                            func PubkeyToIDV4

                                                            func PubkeyToIDV4(key *ecdsa.PublicKey) ID

                                                              PubkeyToIDV4 derives the v4 node address from the given public key.

                                                              func (ID) Bytes

                                                              func (n ID) Bytes() []byte

                                                                Bytes returns a byte slice representation of the ID

                                                                func (ID) GoString

                                                                func (n ID) GoString() string

                                                                  The Go syntax representation of a ID is a call to HexID.

                                                                  func (ID) MarshalText

                                                                  func (n ID) MarshalText() ([]byte, error)

                                                                    MarshalText implements the encoding.TextMarshaler interface.

                                                                    func (ID) String

                                                                    func (n ID) String() string

                                                                      ID prints as a long hexadecimal number.

                                                                      func (ID) TerminalString

                                                                      func (n ID) TerminalString() string

                                                                        TerminalString returns a shortened hex string for terminal logging.

                                                                        func (*ID) UnmarshalText

                                                                        func (n *ID) UnmarshalText(text []byte) error

                                                                          UnmarshalText implements the encoding.TextUnmarshaler interface.

                                                                          type Iterator

                                                                          type Iterator interface {
                                                                          	Next() bool  // moves to next node
                                                                          	Node() *Node // returns current node
                                                                          	Close()      // ends the iterator
                                                                          }

                                                                            Iterator represents a sequence of nodes. The Next method moves to the next node in the sequence. It returns false when the sequence has ended or the iterator is closed. Close may be called concurrently with Next and Node, and interrupts Next if it is blocked.

                                                                            func CycleNodes

                                                                            func CycleNodes(nodes []*Node) Iterator

                                                                              CycleNodes makes an iterator which cycles through the given nodes indefinitely.

                                                                              func Filter

                                                                              func Filter(it Iterator, check func(*Node) bool) Iterator

                                                                                Filter wraps an iterator such that Next only returns nodes for which the 'check' function returns true.

                                                                                func IterNodes

                                                                                func IterNodes(nodes []*Node) Iterator

                                                                                  IterNodes makes an iterator which runs through the given nodes once.

                                                                                  type LocalNode

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

                                                                                    LocalNode produces the signed node record of a local node, i.e. a node run in the current process. Setting ENR entries via the Set method updates the record. A new version of the record is signed on demand when the Node method is called.

                                                                                    func NewLocalNode

                                                                                    func NewLocalNode(db *DB, key *ecdsa.PrivateKey) *LocalNode

                                                                                      NewLocalNode creates a local node.

                                                                                      func (*LocalNode) Database

                                                                                      func (ln *LocalNode) Database() *DB

                                                                                        Database returns the node database associated with the local node.

                                                                                        func (*LocalNode) Delete

                                                                                        func (ln *LocalNode) Delete(e enr.Entry)

                                                                                          Delete removes the given entry from the local record.

                                                                                          func (*LocalNode) ID

                                                                                          func (ln *LocalNode) ID() ID

                                                                                            ID returns the local node ID.

                                                                                            func (*LocalNode) Node

                                                                                            func (ln *LocalNode) Node() *Node

                                                                                              Node returns the current version of the local node record.

                                                                                              func (*LocalNode) Seq

                                                                                              func (ln *LocalNode) Seq() uint64

                                                                                                Seq returns the current sequence number of the local node record.

                                                                                                func (*LocalNode) Set

                                                                                                func (ln *LocalNode) Set(e enr.Entry)

                                                                                                  Set puts the given entry into the local record, overwriting any existing value. Use Set*IP and SetFallbackUDP to set IP addresses and UDP port, otherwise they'll be overwritten by the endpoint predictor.

                                                                                                  func (*LocalNode) SetFallbackIP

                                                                                                  func (ln *LocalNode) SetFallbackIP(ip net.IP)

                                                                                                    SetFallbackIP sets the last-resort IP address. This address is used if no endpoint prediction can be made and no static IP is set.

                                                                                                    func (*LocalNode) SetFallbackUDP

                                                                                                    func (ln *LocalNode) SetFallbackUDP(port int)

                                                                                                      SetFallbackUDP sets the last-resort UDP-on-IPv4 port. This port is used if no endpoint prediction can be made.

                                                                                                      func (*LocalNode) SetStaticIP

                                                                                                      func (ln *LocalNode) SetStaticIP(ip net.IP)

                                                                                                        SetStaticIP sets the local IP to the given one unconditionally. This disables endpoint prediction.

                                                                                                        func (*LocalNode) UDPContact

                                                                                                        func (ln *LocalNode) UDPContact(toaddr *net.UDPAddr)

                                                                                                          UDPContact should be called whenever the local node has announced itself to another node via UDP. It feeds the local endpoint predictor.

                                                                                                          func (*LocalNode) UDPEndpointStatement

                                                                                                          func (ln *LocalNode) UDPEndpointStatement(fromaddr, endpoint *net.UDPAddr)

                                                                                                            UDPEndpointStatement should be called whenever a statement about the local node's UDP endpoint is received. It feeds the local endpoint predictor.

                                                                                                            type Node

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

                                                                                                              Node represents a host on the network.

                                                                                                              func MustParse

                                                                                                              func MustParse(rawurl string) *Node

                                                                                                                MustParse parses a node record or enode:// URL. It panics if the input is invalid.

                                                                                                                func MustParseV4

                                                                                                                func MustParseV4(rawurl string) *Node

                                                                                                                  MustParseV4 parses a node URL. It panics if the URL is not valid.

                                                                                                                  func New

                                                                                                                  func New(validSchemes enr.IdentityScheme, r *enr.Record) (*Node, error)

                                                                                                                    New wraps a node record. The record must be valid according to the given identity scheme.

                                                                                                                    func NewV4

                                                                                                                    func NewV4(pubkey *ecdsa.PublicKey, ip net.IP, tcp, udp int) *Node

                                                                                                                      NewV4 creates a node from discovery v4 node information. The record contained in the node has a zero-length signature.

                                                                                                                      func Parse

                                                                                                                      func Parse(validSchemes enr.IdentityScheme, input string) (*Node, error)

                                                                                                                        Parse decodes and verifies a base64-encoded node record.

                                                                                                                        func ParseV4

                                                                                                                        func ParseV4(rawurl string) (*Node, error)

                                                                                                                          ParseV4 parses a node URL.

                                                                                                                          There are two basic forms of node URLs:

                                                                                                                          - incomplete nodes, which only have the public key (node ID)
                                                                                                                          - complete nodes, which contain the public key and IP/Port information
                                                                                                                          

                                                                                                                          For incomplete nodes, the designator must look like one of these

                                                                                                                          enode://<hex node id>
                                                                                                                          <hex node id>
                                                                                                                          

                                                                                                                          For complete nodes, the node ID is encoded in the username portion of the URL, separated from the host by an @ sign. The hostname can only be given as an IP address or using DNS domain name. The port in the host name section is the TCP listening port. If the TCP and UDP (discovery) ports differ, the UDP port is specified as query parameter "discport".

                                                                                                                          In the following example, the node URL describes a node with IP address 10.3.58.6, TCP listening port 30303 and UDP discovery port 30301.

                                                                                                                          enode://<hex node id>@10.3.58.6:30303?discport=30301
                                                                                                                          

                                                                                                                          func ReadNodes

                                                                                                                          func ReadNodes(it Iterator, n int) []*Node

                                                                                                                            ReadNodes reads at most n nodes from the given iterator. The return value contains no duplicates and no nil values. To prevent looping indefinitely for small repeating node sequences, this function calls Next at most n times.

                                                                                                                            func SignNull

                                                                                                                            func SignNull(r *enr.Record, id ID) *Node

                                                                                                                            func (*Node) ID

                                                                                                                            func (n *Node) ID() ID

                                                                                                                              ID returns the node identifier.

                                                                                                                              func (*Node) IP

                                                                                                                              func (n *Node) IP() net.IP

                                                                                                                                IP returns the IP address of the node. This prefers IPv4 addresses.

                                                                                                                                func (*Node) Incomplete

                                                                                                                                func (n *Node) Incomplete() bool

                                                                                                                                  Incomplete returns true for nodes with no IP address.

                                                                                                                                  func (*Node) Load

                                                                                                                                  func (n *Node) Load(k enr.Entry) error

                                                                                                                                    Load retrieves an entry from the underlying record.

                                                                                                                                    func (*Node) MarshalText

                                                                                                                                    func (n *Node) MarshalText() ([]byte, error)

                                                                                                                                      MarshalText implements encoding.TextMarshaler.

                                                                                                                                      func (*Node) Pubkey

                                                                                                                                      func (n *Node) Pubkey() *ecdsa.PublicKey

                                                                                                                                        Pubkey returns the secp256k1 public key of the node, if present.

                                                                                                                                        func (*Node) Record

                                                                                                                                        func (n *Node) Record() *enr.Record

                                                                                                                                          Record returns the node's record. The return value is a copy and may be modified by the caller.

                                                                                                                                          func (*Node) Seq

                                                                                                                                          func (n *Node) Seq() uint64

                                                                                                                                            Seq returns the sequence number of the underlying record.

                                                                                                                                            func (*Node) String

                                                                                                                                            func (n *Node) String() string

                                                                                                                                              String returns the text representation of the record.

                                                                                                                                              func (*Node) TCP

                                                                                                                                              func (n *Node) TCP() int

                                                                                                                                                UDP returns the TCP port of the node.

                                                                                                                                                func (*Node) UDP

                                                                                                                                                func (n *Node) UDP() int

                                                                                                                                                  UDP returns the UDP port of the node.

                                                                                                                                                  func (*Node) URLv4

                                                                                                                                                  func (n *Node) URLv4() string

                                                                                                                                                  func (*Node) UnmarshalText

                                                                                                                                                  func (n *Node) UnmarshalText(text []byte) error

                                                                                                                                                    UnmarshalText implements encoding.TextUnmarshaler.

                                                                                                                                                    func (*Node) ValidateComplete

                                                                                                                                                    func (n *Node) ValidateComplete() error

                                                                                                                                                      ValidateComplete checks whether n has a valid IP and UDP port. Deprecated: don't use this method.

                                                                                                                                                      type NullID

                                                                                                                                                      type NullID struct{}

                                                                                                                                                        NullID is the "null" ENR identity scheme. This scheme stores the node ID in the record without any signature.

                                                                                                                                                        func (NullID) NodeAddr

                                                                                                                                                        func (NullID) NodeAddr(r *enr.Record) []byte

                                                                                                                                                        func (NullID) Verify

                                                                                                                                                        func (NullID) Verify(r *enr.Record, sig []byte) error

                                                                                                                                                        type Secp256k1

                                                                                                                                                        type Secp256k1 ecdsa.PublicKey

                                                                                                                                                          Secp256k1 is the "secp256k1" key, which holds a public key.

                                                                                                                                                          func (*Secp256k1) DecodeRLP

                                                                                                                                                          func (v *Secp256k1) DecodeRLP(s *rlp.Stream) error

                                                                                                                                                            DecodeRLP implements rlp.Decoder.

                                                                                                                                                            func (Secp256k1) ENRKey

                                                                                                                                                            func (v Secp256k1) ENRKey() string

                                                                                                                                                            func (Secp256k1) EncodeRLP

                                                                                                                                                            func (v Secp256k1) EncodeRLP(w io.Writer) error

                                                                                                                                                              EncodeRLP implements rlp.Encoder.

                                                                                                                                                              type V4ID

                                                                                                                                                              type V4ID struct{}

                                                                                                                                                                v4ID is the "v4" identity scheme.

                                                                                                                                                                func (V4ID) NodeAddr

                                                                                                                                                                func (V4ID) NodeAddr(r *enr.Record) []byte

                                                                                                                                                                func (V4ID) Verify

                                                                                                                                                                func (V4ID) Verify(r *enr.Record, sig []byte) error