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-rw-r--r--p2p/discover/node.go422
1 files changed, 47 insertions, 375 deletions
diff --git a/p2p/discover/node.go b/p2p/discover/node.go
index 3b0c84115..7ddf04fe8 100644
--- a/p2p/discover/node.go
+++ b/p2p/discover/node.go
@@ -18,415 +18,87 @@ package discover
import (
"crypto/ecdsa"
- "crypto/elliptic"
- "encoding/hex"
"errors"
- "fmt"
"math/big"
- "math/rand"
"net"
- "net/url"
- "regexp"
- "strconv"
- "strings"
"time"
- "github.com/ethereum/go-ethereum/common"
+ "github.com/ethereum/go-ethereum/common/math"
"github.com/ethereum/go-ethereum/crypto"
"github.com/ethereum/go-ethereum/crypto/secp256k1"
+ "github.com/ethereum/go-ethereum/p2p/enode"
)
-const NodeIDBits = 512
-
-// Node represents a host on the network.
+// node represents a host on the network.
// The fields of Node may not be modified.
-type Node struct {
- IP net.IP // len 4 for IPv4 or 16 for IPv6
- UDP, TCP uint16 // port numbers
- ID NodeID // the node's public key
-
- // This is a cached copy of sha3(ID) which is used for node
- // distance calculations. This is part of Node in order to make it
- // possible to write tests that need a node at a certain distance.
- // In those tests, the content of sha will not actually correspond
- // with ID.
- sha common.Hash
-
- // Time when the node was added to the table.
- addedAt time.Time
-}
-
-// NewNode creates a new node. It is mostly meant to be used for
-// testing purposes.
-func NewNode(id NodeID, ip net.IP, udpPort, tcpPort uint16) *Node {
- if ipv4 := ip.To4(); ipv4 != nil {
- ip = ipv4
- }
- return &Node{
- IP: ip,
- UDP: udpPort,
- TCP: tcpPort,
- ID: id,
- sha: crypto.Keccak256Hash(id[:]),
- }
-}
-
-func (n *Node) addr() *net.UDPAddr {
- return &net.UDPAddr{IP: n.IP, Port: int(n.UDP)}
-}
-
-// Incomplete returns true for nodes with no IP address.
-func (n *Node) Incomplete() bool {
- return n.IP == nil
-}
-
-// checks whether n is a valid complete node.
-func (n *Node) validateComplete() error {
- if n.Incomplete() {
- return errors.New("incomplete node")
- }
- if n.UDP == 0 {
- return errors.New("missing UDP port")
- }
- if n.TCP == 0 {
- return errors.New("missing TCP port")
- }
- if n.IP.IsMulticast() || n.IP.IsUnspecified() {
- return errors.New("invalid IP (multicast/unspecified)")
- }
- _, err := n.ID.Pubkey() // validate the key (on curve, etc.)
- return err
-}
-
-// The string representation of a Node is a URL.
-// Please see ParseNode for a description of the format.
-func (n *Node) String() string {
- u := url.URL{Scheme: "enode"}
- if n.Incomplete() {
- u.Host = fmt.Sprintf("%x", n.ID[:])
- } else {
- addr := net.TCPAddr{IP: n.IP, Port: int(n.TCP)}
- u.User = url.User(fmt.Sprintf("%x", n.ID[:]))
- u.Host = addr.String()
- if n.UDP != n.TCP {
- u.RawQuery = "discport=" + strconv.Itoa(int(n.UDP))
- }
- }
- return u.String()
-}
-
-var incompleteNodeURL = regexp.MustCompile("(?i)^(?:enode://)?([0-9a-f]+)$")
-
-// 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
-//
-// 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 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 ParseNode(rawurl string) (*Node, error) {
- if m := incompleteNodeURL.FindStringSubmatch(rawurl); m != nil {
- id, err := HexID(m[1])
- if err != nil {
- return nil, fmt.Errorf("invalid node ID (%v)", err)
- }
- return NewNode(id, nil, 0, 0), nil
- }
- return parseComplete(rawurl)
+type node struct {
+ enode.Node
+ addedAt time.Time // time when the node was added to the table
}
-func parseComplete(rawurl string) (*Node, error) {
- var (
- id NodeID
- ip net.IP
- tcpPort, udpPort uint64
- )
- u, err := url.Parse(rawurl)
- if err != nil {
- return nil, err
- }
- if u.Scheme != "enode" {
- return nil, errors.New("invalid URL scheme, want \"enode\"")
- }
- // Parse the Node ID from the user portion.
- if u.User == nil {
- return nil, errors.New("does not contain node ID")
- }
- if id, err = HexID(u.User.String()); err != nil {
- return nil, fmt.Errorf("invalid node ID (%v)", err)
- }
- // Parse the IP address.
- host, port, err := net.SplitHostPort(u.Host)
- if err != nil {
- return nil, fmt.Errorf("invalid host: %v", err)
- }
- if ip = net.ParseIP(host); ip == nil {
- return nil, errors.New("invalid IP address")
- }
- // Ensure the IP is 4 bytes long for IPv4 addresses.
- if ipv4 := ip.To4(); ipv4 != nil {
- ip = ipv4
- }
- // Parse the port numbers.
- if tcpPort, err = strconv.ParseUint(port, 10, 16); err != nil {
- return nil, errors.New("invalid port")
- }
- udpPort = tcpPort
- qv := u.Query()
- if qv.Get("discport") != "" {
- udpPort, err = strconv.ParseUint(qv.Get("discport"), 10, 16)
- if err != nil {
- return nil, errors.New("invalid discport in query")
- }
- }
- return NewNode(id, ip, uint16(udpPort), uint16(tcpPort)), nil
-}
-
-// MustParseNode parses a node URL. It panics if the URL is not valid.
-func MustParseNode(rawurl string) *Node {
- n, err := ParseNode(rawurl)
- if err != nil {
- panic("invalid node URL: " + err.Error())
- }
- return n
-}
+type encPubkey [64]byte
-// MarshalText implements encoding.TextMarshaler.
-func (n *Node) MarshalText() ([]byte, error) {
- return []byte(n.String()), nil
+func encodePubkey(key *ecdsa.PublicKey) encPubkey {
+ var e encPubkey
+ math.ReadBits(key.X, e[:len(e)/2])
+ math.ReadBits(key.Y, e[len(e)/2:])
+ return e
}
-// UnmarshalText implements encoding.TextUnmarshaler.
-func (n *Node) UnmarshalText(text []byte) error {
- dec, err := ParseNode(string(text))
- if err == nil {
- *n = *dec
- }
- return err
-}
-
-// NodeID is a unique identifier for each node.
-// The node identifier is a marshaled elliptic curve public key.
-type NodeID [NodeIDBits / 8]byte
-
-// Bytes returns a byte slice representation of the NodeID
-func (n NodeID) Bytes() []byte {
- return n[:]
-}
-
-// NodeID prints as a long hexadecimal number.
-func (n NodeID) String() string {
- return fmt.Sprintf("%x", n[:])
-}
-
-// The Go syntax representation of a NodeID is a call to HexID.
-func (n NodeID) GoString() string {
- return fmt.Sprintf("discover.HexID(\"%x\")", n[:])
-}
-
-// TerminalString returns a shortened hex string for terminal logging.
-func (n NodeID) TerminalString() string {
- return hex.EncodeToString(n[:8])
-}
-
-// MarshalText implements the encoding.TextMarshaler interface.
-func (n NodeID) MarshalText() ([]byte, error) {
- return []byte(hex.EncodeToString(n[:])), nil
-}
-
-// UnmarshalText implements the encoding.TextUnmarshaler interface.
-func (n *NodeID) UnmarshalText(text []byte) error {
- id, err := HexID(string(text))
- if err != nil {
- return err
- }
- *n = id
- return nil
-}
-
-// BytesID converts a byte slice to a NodeID
-func BytesID(b []byte) (NodeID, error) {
- var id NodeID
- if len(b) != len(id) {
- return id, fmt.Errorf("wrong length, want %d bytes", len(id))
- }
- copy(id[:], b)
- return id, nil
-}
-
-// MustBytesID converts a byte slice to a NodeID.
-// It panics if the byte slice is not a valid NodeID.
-func MustBytesID(b []byte) NodeID {
- id, err := BytesID(b)
- if err != nil {
- panic(err)
+func decodePubkey(e encPubkey) (*ecdsa.PublicKey, error) {
+ p := &ecdsa.PublicKey{Curve: crypto.S256(), X: new(big.Int), Y: new(big.Int)}
+ half := len(e) / 2
+ p.X.SetBytes(e[:half])
+ p.Y.SetBytes(e[half:])
+ if !p.Curve.IsOnCurve(p.X, p.Y) {
+ return nil, errors.New("invalid secp256k1 curve point")
}
- return id
+ return p, nil
}
-// HexID converts a hex string to a NodeID.
-// The string may be prefixed with 0x.
-func HexID(in string) (NodeID, error) {
- var id NodeID
- b, err := hex.DecodeString(strings.TrimPrefix(in, "0x"))
- if err != nil {
- return id, err
- } else if len(b) != len(id) {
- return id, fmt.Errorf("wrong length, want %d hex chars", len(id)*2)
- }
- copy(id[:], b)
- return id, nil
+func (e encPubkey) id() enode.ID {
+ return enode.ID(crypto.Keccak256Hash(e[:]))
}
-// MustHexID converts a hex string to a NodeID.
-// It panics if the string is not a valid NodeID.
-func MustHexID(in string) NodeID {
- id, err := HexID(in)
+// recoverNodeKey computes the public key used to sign the
+// given hash from the signature.
+func recoverNodeKey(hash, sig []byte) (key encPubkey, err error) {
+ pubkey, err := secp256k1.RecoverPubkey(hash, sig)
if err != nil {
- panic(err)
+ return key, err
}
- return id
+ copy(key[:], pubkey[1:])
+ return key, nil
}
-// PubkeyID returns a marshaled representation of the given public key.
-func PubkeyID(pub *ecdsa.PublicKey) NodeID {
- var id NodeID
- pbytes := elliptic.Marshal(pub.Curve, pub.X, pub.Y)
- if len(pbytes)-1 != len(id) {
- panic(fmt.Errorf("need %d bit pubkey, got %d bits", (len(id)+1)*8, len(pbytes)))
- }
- copy(id[:], pbytes[1:])
- return id
+func wrapNode(n *enode.Node) *node {
+ return &node{Node: *n}
}
-// 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 (id NodeID) Pubkey() (*ecdsa.PublicKey, error) {
- p := &ecdsa.PublicKey{Curve: crypto.S256(), X: new(big.Int), Y: new(big.Int)}
- half := len(id) / 2
- p.X.SetBytes(id[:half])
- p.Y.SetBytes(id[half:])
- if !p.Curve.IsOnCurve(p.X, p.Y) {
- return nil, errors.New("id is invalid secp256k1 curve point")
+func wrapNodes(ns []*enode.Node) []*node {
+ result := make([]*node, len(ns))
+ for i, n := range ns {
+ result[i] = wrapNode(n)
}
- return p, nil
+ return result
}
-// recoverNodeID computes the public key used to sign the
-// given hash from the signature.
-func recoverNodeID(hash, sig []byte) (id NodeID, err error) {
- pubkey, err := secp256k1.RecoverPubkey(hash, sig)
- if err != nil {
- return id, err
- }
- if len(pubkey)-1 != len(id) {
- return id, fmt.Errorf("recovered pubkey has %d bits, want %d bits", len(pubkey)*8, (len(id)+1)*8)
- }
- for i := range id {
- id[i] = pubkey[i+1]
- }
- return id, nil
+func unwrapNode(n *node) *enode.Node {
+ return &n.Node
}
-// 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 distcmp(target, a, b common.Hash) int {
- for i := range target {
- da := a[i] ^ target[i]
- db := b[i] ^ target[i]
- if da > db {
- return 1
- } else if da < db {
- return -1
- }
+func unwrapNodes(ns []*node) []*enode.Node {
+ result := make([]*enode.Node, len(ns))
+ for i, n := range ns {
+ result[i] = unwrapNode(n)
}
- return 0
+ return result
}
-// table of leading zero counts for bytes [0..255]
-var lzcount = [256]int{
- 8, 7, 6, 6, 5, 5, 5, 5,
- 4, 4, 4, 4, 4, 4, 4, 4,
- 3, 3, 3, 3, 3, 3, 3, 3,
- 3, 3, 3, 3, 3, 3, 3, 3,
- 2, 2, 2, 2, 2, 2, 2, 2,
- 2, 2, 2, 2, 2, 2, 2, 2,
- 2, 2, 2, 2, 2, 2, 2, 2,
- 2, 2, 2, 2, 2, 2, 2, 2,
- 1, 1, 1, 1, 1, 1, 1, 1,
- 1, 1, 1, 1, 1, 1, 1, 1,
- 1, 1, 1, 1, 1, 1, 1, 1,
- 1, 1, 1, 1, 1, 1, 1, 1,
- 1, 1, 1, 1, 1, 1, 1, 1,
- 1, 1, 1, 1, 1, 1, 1, 1,
- 1, 1, 1, 1, 1, 1, 1, 1,
- 1, 1, 1, 1, 1, 1, 1, 1,
- 0, 0, 0, 0, 0, 0, 0, 0,
- 0, 0, 0, 0, 0, 0, 0, 0,
- 0, 0, 0, 0, 0, 0, 0, 0,
- 0, 0, 0, 0, 0, 0, 0, 0,
- 0, 0, 0, 0, 0, 0, 0, 0,
- 0, 0, 0, 0, 0, 0, 0, 0,
- 0, 0, 0, 0, 0, 0, 0, 0,
- 0, 0, 0, 0, 0, 0, 0, 0,
- 0, 0, 0, 0, 0, 0, 0, 0,
- 0, 0, 0, 0, 0, 0, 0, 0,
- 0, 0, 0, 0, 0, 0, 0, 0,
- 0, 0, 0, 0, 0, 0, 0, 0,
- 0, 0, 0, 0, 0, 0, 0, 0,
- 0, 0, 0, 0, 0, 0, 0, 0,
- 0, 0, 0, 0, 0, 0, 0, 0,
- 0, 0, 0, 0, 0, 0, 0, 0,
+func (n *node) addr() *net.UDPAddr {
+ return &net.UDPAddr{IP: n.IP(), Port: n.UDP()}
}
-// logdist returns the logarithmic distance between a and b, log2(a ^ b).
-func logdist(a, b common.Hash) int {
- lz := 0
- for i := range a {
- x := a[i] ^ b[i]
- if x == 0 {
- lz += 8
- } else {
- lz += lzcount[x]
- break
- }
- }
- return len(a)*8 - lz
-}
-
-// hashAtDistance returns a random hash such that logdist(a, b) == n
-func hashAtDistance(a common.Hash, n int) (b common.Hash) {
- if n == 0 {
- return a
- }
- // flip bit at position n, fill the rest with random bits
- b = a
- pos := len(a) - n/8 - 1
- bit := byte(0x01) << (byte(n%8) - 1)
- if bit == 0 {
- pos++
- bit = 0x80
- }
- b[pos] = a[pos]&^bit | ^a[pos]&bit // TODO: randomize end bits
- for i := pos + 1; i < len(a); i++ {
- b[i] = byte(rand.Intn(255))
- }
- return b
+func (n *node) String() string {
+ return n.Node.String()
}
generated by cgit (git 2.34.1) at 2024-11-12 19:59:53 +0800