Documentation ¶
Overview ¶
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 ¶
- Constants
- func NewSimpleStorage(nodeType NodeType, noDiscover bool, max int, authorizedNodes []*Node) *simpleStorage
- func StringNodeType(nType NodeType) string
- type Config
- type Discovery
- type DiscoveryType
- type KademliaStorage
- type Node
- type NodeID
- func (n NodeID) Bytes() []byte
- func (n NodeID) GoString() string
- func (n NodeID) MarshalText() ([]byte, error)
- func (id NodeID) Pubkey() (*ecdsa.PublicKey, error)
- func (n NodeID) ShortString() string
- func (n NodeID) String() string
- func (n NodeID) TerminalString() string
- func (n *NodeID) UnmarshalText(text []byte) error
- type NodeType
- type ReadPacket
- type Table
- func (tab *Table) Bond(pinged bool, id NodeID, addr *net.UDPAddr, tcpPort uint16, nType NodeType) (*Node, error)
- func (tab *Table) Close()
- func (tab *Table) CreateUpdateNodeOnDB(n *Node) error
- func (tab *Table) CreateUpdateNodeOnTable(n *Node) error
- func (tab *Table) DeleteAuthorizedNodes(nodes []*Node)
- func (tab *Table) DeleteNodeFromDB(n *Node) error
- func (tab *Table) DeleteNodeFromTable(n *Node) error
- func (tab *Table) GetAuthorizedNodes() []*Node
- func (tab *Table) GetBucketEntries() []*Node
- func (tab *Table) GetNodeFromDB(id NodeID) (*Node, error)
- func (tab *Table) GetNodes(targetNT NodeType, max int) []*Node
- func (tab *Table) GetReplacements() []*Node
- func (tab *Table) HasBond(id NodeID) bool
- func (tab *Table) IsAuthorized(fromID NodeID, nType NodeType) bool
- func (tab *Table) Lookup(targetID NodeID, targetType NodeType) []*Node
- func (tab *Table) Name() string
- func (tab *Table) PutAuthorizedNodes(nodes []*Node)
- func (tab *Table) ReadRandomNodes(buf []*Node, nType NodeType) (n int)
- func (tab *Table) Resolve(targetID NodeID, targetType NodeType) *Node
- func (tab *Table) RetrieveNodes(target common.Hash, nType NodeType, nresults int) []*Node
- func (tab *Table) Self() *Node
Examples ¶
Constants ¶
const ( NodeTypeUnknown = NodeType(iota) NodeTypeCN NodeTypePN NodeTypeEN NodeTypeBN )
Node types
const NodeIDBits = 512
const Version = 4
Variables ¶
This section is empty.
Functions ¶
func NewSimpleStorage ¶
func StringNodeType ¶
StringNodeType converts NodeType to string
Types ¶
type Config ¶
type Config struct { NetworkID uint64 // These settings are required and configure the UDP listener: PrivateKey *ecdsa.PrivateKey // These settings are optional: AnnounceAddr *net.UDPAddr // local address announced in the DHT NodeDBPath string // if set, the node database is stored at this filesystem location NetRestrict *netutil.Netlist // network whitelist Bootnodes []*Node // list of bootstrap nodes Unhandled chan<- ReadPacket // unhandled packets are sent on this channel // These settings are required for create Table and UDP Id NodeID Addr *net.UDPAddr Conn conn NodeType NodeType // These settings are required for discovery packet control MaxNeighborsNode uint AuthorizedNodes []*Node // contains filtered or unexported fields }
Config holds Table-related settings.
type Discovery ¶
type Discovery interface { Self() *Node Close() Resolve(target NodeID, targetType NodeType) *Node Lookup(target NodeID, targetType NodeType) []*Node GetNodes(targetType NodeType, max int) []*Node ReadRandomNodes([]*Node, NodeType) int RetrieveNodes(target common.Hash, nType NodeType, nresults int) []*Node // replace of closest():Table HasBond(id NodeID) bool Bond(pinged bool, id NodeID, addr *net.UDPAddr, tcpPort uint16, nType NodeType) (*Node, error) IsAuthorized(fromID NodeID, nType NodeType) bool // interfaces for API Name() string CreateUpdateNodeOnDB(n *Node) error CreateUpdateNodeOnTable(n *Node) error GetNodeFromDB(id NodeID) (*Node, error) DeleteNodeFromDB(n *Node) error DeleteNodeFromTable(n *Node) error GetBucketEntries() []*Node GetReplacements() []*Node GetAuthorizedNodes() []*Node PutAuthorizedNodes(nodes []*Node) DeleteAuthorizedNodes(nodes []*Node) }
func NewDiscovery ¶
type DiscoveryType ¶
type DiscoveryType uint8
type KademliaStorage ¶
type KademliaStorage struct {
// contains filtered or unexported fields
}
type Node ¶
type Node struct { IP net.IP // len 4 for IPv4 or 16 for IPv6 UDP uint16 // discovery port numbers TCP uint16 // TCP listening port number TCPs []uint16 // TCP listening port number including both main port and subports ID NodeID // the node's public key NType NodeType // the node's type (cn, pn, en, bn) // PortOrder is the order of the ports that should be connected in multi-channel. PortOrder uint16 // contains filtered or unexported fields }
Node represents a host on the network. The fields of Node may not be modified.
func MustParseNode ¶
MustParseNode parses a node URL. It panics if the URL is not valid.
func NewNode ¶
func NewNode(id NodeID, ip net.IP, udpPort, tcpPort uint16, tcpSubports []uint16, nType NodeType) *Node
NewNode creates a new node. It is mostly meant to be used for testing purposes.
Example ¶
id := MustHexID("1dd9d65c4552b5eb43d5ad55a2ee3f56c6cbc1c64a5c8d659f51fcd51bace24351232b8d7821617d2b29b54b81cdefb9b3e9c37d7fd5f63270bcc9e1a6f6a439") // Complete nodes contain UDP and TCP endpoints: n1 := NewNode(id, net.ParseIP("2001:db8:3c4d:15::abcd:ef12"), 52150, 30303, nil, NodeTypeUnknown) fmt.Println("n1:", n1) fmt.Println("n1.Incomplete() ->", n1.Incomplete()) // An incomplete node can be created by passing zero values // for all parameters except id. n2 := NewNode(id, nil, 0, 0, nil, NodeTypeUnknown) fmt.Println("n2:", n2) fmt.Println("n2.Incomplete() ->", n2.Incomplete())
Output: n1: kni://1dd9d65c4552b5eb43d5ad55a2ee3f56c6cbc1c64a5c8d659f51fcd51bace24351232b8d7821617d2b29b54b81cdefb9b3e9c37d7fd5f63270bcc9e1a6f6a439@[2001:db8:3c4d:15::abcd:ef12]:30303?discport=52150 n1.Incomplete() -> false n2: kni://1dd9d65c4552b5eb43d5ad55a2ee3f56c6cbc1c64a5c8d659f51fcd51bace24351232b8d7821617d2b29b54b81cdefb9b3e9c37d7fd5f63270bcc9e1a6f6a439 n2.Incomplete() -> true
func ParseNode ¶
ParseNode parses a node designator.
There are two basic forms of node designators
- 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
kni://<hex node id> or 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, DNS domain names are not allowed. 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 examples, the node URL describes a node with IP address 10.3.58.6, TCP listening port 30303 and UDP discovery port 30301.
kni://<hex node id>@10.3.58.6:30303?&subport=30304&discport=30301[&ntype=cn|pn|en|bn] enode://<hex node id>@10.3.58.6:30303?discport=30301[&ntype=cn|pn|en|bn]
func (*Node) AddSubport ¶
AddSubport adds a new port to TCPs TCPs contains unique ports
func (*Node) CompareNode ¶
CompareNode implements the compare the all node field and return its result
func (*Node) Incomplete ¶
Incomplete returns true for nodes with no IP address.
func (*Node) MarshalText ¶
MarshalText implements encoding.TextMarshaler.
func (*Node) String ¶
The string representation of a Node is a URL. Please see ParseNode for a description of the format.
func (*Node) UnmarshalText ¶
UnmarshalText implements encoding.TextUnmarshaler.
type NodeID ¶
type NodeID [NodeIDBits / 8]byte
NodeID is a unique identifier for each node. The node identifier is a marshaled elliptic curve public key.
func MustBytesID ¶
MustBytesID converts a byte slice to a NodeID. It panics if the byte slice is not a valid NodeID.
func MustHexID ¶
MustHexID converts a hex string to a NodeID. It panics if the string is not a valid NodeID.
func (NodeID) MarshalText ¶
MarshalText implements the encoding.TextMarshaler interface.
func (NodeID) Pubkey ¶
Pubkey returns the public key represented by the node ID. It returns an error if the ID is not a point on the curve.
func (NodeID) ShortString ¶
ShortString returns a shortened 4 digits hex string for logging
func (NodeID) TerminalString ¶
TerminalString returns a shortened hex string for terminal logging.
func (*NodeID) UnmarshalText ¶
UnmarshalText implements the encoding.TextUnmarshaler interface.
type ReadPacket ¶
ReadPacket is sent to the unhandled channel when it could not be processed
type Table ¶
type Table struct {
// contains filtered or unexported fields
}
func (*Table) Bond ¶
func (tab *Table) Bond(pinged bool, id NodeID, addr *net.UDPAddr, tcpPort uint16, nType NodeType) (*Node, error)
Bond ensures the local node has a bond with the given remote node. It also attempts to insert the node into the table if bonding succeeds. The caller must not hold tab.mutex.
A bond is must be established before sending findnode requests. Both sides must have completed a ping/pong exchange for a bond to exist. The total number of active bonding processes is limited in order to restrain network use.
bond is meant to operate idempotently in that bonding with a remote node which still remembers a previously established bond will work. The remote node will simply not send a ping back, causing waitping to time out.
If pinged is true, the remote node has just pinged us and one half of the process can be skipped.
func (*Table) Close ¶
func (tab *Table) Close()
Close terminates the network listener and flushes the node database.
func (*Table) CreateUpdateNodeOnDB ¶
CreateUpdateNodeOnDB inserts - potentially overwriting - a node into the peer database.
func (*Table) CreateUpdateNodeOnTable ¶
CreateUpdateNodeOnDB inserts - potentially overwriting - a node into the associated storage.
func (*Table) DeleteAuthorizedNodes ¶
func (*Table) DeleteNodeFromDB ¶
DeleteNodeFromDB deletes node which has id in peer database.
func (*Table) DeleteNodeFromTable ¶
DeleteNodeFromDB deletes node which has id in the associated table.
func (*Table) GetAuthorizedNodes ¶
func (*Table) GetBucketEntries ¶
GetBucketEntries returns nodes in peer databases.
func (*Table) GetNodeFromDB ¶
GetNodeFromDB returns a node which has id in peer database.
func (*Table) GetReplacements ¶
GetBucketEntries returns nodes which place in replacements in peer databases.
func (*Table) Lookup ¶
Lookup performs a network search for nodes close to the given target. It approaches the target by querying nodes that are closer to it on each iteration. The given target does not need to be an actual node identifier.
func (*Table) PutAuthorizedNodes ¶
func (*Table) ReadRandomNodes ¶
ReadRandomNodes fills the given slice with random nodes from the table. It will not write the same node more than once. The nodes in the slice are copies and can be modified by the caller.
func (*Table) Resolve ¶
Resolve searches for a specific node with the given ID. It returns nil if the node could not be found.
func (*Table) RetrieveNodes ¶
RetrieveNodes returns node list except bootnode. This method is used to make a result of FINDNODE request.