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Merge branch 'fjl-p2p-handshake-2' into poc-9

This commit is contained in:
obscuren 2015-03-05 17:26:41 +01:00
parent fabaf4f1f0 ba0c41436c
commit 12ca70537f
15 changed files with 786 additions and 770 deletions
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9
eth/backend.go
View File

@ -107,11 +107,9 @@ func (cfg *Config) nodeKey() (*ecdsa.PrivateKey, error) {
type Ethereum struct {
// Channel for shutting down the ethereum
shutdownChan chan bool
quit chan bool
// DB interface
db ethutil.Database
blacklist p2p.Blacklist
db ethutil.Database
//*** SERVICES ***
// State manager for processing new blocks and managing the over all states
@ -169,10 +167,8 @@ func New(config *Config) (*Ethereum, error) {
eth := &Ethereum{
shutdownChan: make(chan bool),
quit: make(chan bool),
db: db,
keyManager: keyManager,
blacklist: p2p.NewBlacklist(),
eventMux: &event.TypeMux{},
logger: ethlogger,
}
@ -205,7 +201,6 @@ func New(config *Config) (*Ethereum, error) {
Name: config.Name,
MaxPeers: config.MaxPeers,
Protocols: protocols,
Blacklist: eth.blacklist,
NAT: config.NAT,
NoDial: !config.Dial,
BootstrapNodes: config.parseBootNodes(),
@ -279,8 +274,6 @@ func (s *Ethereum) Stop() {
// Close the database
defer s.db.Close()
close(s.quit)
s.txSub.Unsubscribe() // quits txBroadcastLoop
s.blockSub.Unsubscribe() // quits blockBroadcastLoop

40
eth/protocol.go
View File

@ -3,7 +3,6 @@ package eth
import (
"bytes"
"fmt"
"io"
"math/big"
"github.com/ethereum/go-ethereum/core/types"
@ -188,33 +187,37 @@ func (self *ethProtocol) handle() error {
case BlockHashesMsg:
msgStream := rlp.NewStream(msg.Payload)
var err error
var i int
iter := func() (hash []byte, ok bool) {
hash, err = msgStream.Bytes()
if err == nil {
i++
ok = true
} else {
if err != io.EOF {
self.protoError(ErrDecode, "msg %v: after %v hashes : %v", msg, i, err)
}
}
return
if _, err := msgStream.List(); err != nil {
return err
}
var i int
iter := func() (hash []byte, ok bool) {
hash, err := msgStream.Bytes()
if err == rlp.EOL {
return nil, false
} else if err != nil {
self.protoError(ErrDecode, "msg %v: after %v hashes : %v", msg, i, err)
return nil, false
}
i++
return hash, true
}
self.blockPool.AddBlockHashes(iter, self.id)
case GetBlocksMsg:
msgStream := rlp.NewStream(msg.Payload)
if _, err := msgStream.List(); err != nil {
return err
}
var blocks []interface{}
var i int
for {
i++
var hash []byte
if err := msgStream.Decode(&hash); err != nil {
if err == io.EOF {
if err == rlp.EOL {
break
} else {
return self.protoError(ErrDecode, "msg %v: %v", msg, err)
@ -232,10 +235,13 @@ func (self *ethProtocol) handle() error {
case BlocksMsg:
msgStream := rlp.NewStream(msg.Payload)
if _, err := msgStream.List(); err != nil {
return err
}
for {
var block types.Block
if err := msgStream.Decode(&block); err != nil {
if err == io.EOF {
if err == rlp.EOL {
break
} else {
return self.protoError(ErrDecode, "msg %v: %v", msg, err)

15
p2p/discover/node.go
View File

@ -7,6 +7,7 @@ import (
"errors"
"fmt"
"io"
"math/big"
"math/rand"
"net"
"net/url"
@ -14,6 +15,7 @@ import (
"strings"
"time"
"github.com/ethereum/go-ethereum/crypto"
"github.com/ethereum/go-ethereum/crypto/secp256k1"
"github.com/ethereum/go-ethereum/rlp"
)
@ -187,6 +189,19 @@ func PubkeyID(pub *ecdsa.PublicKey) NodeID {
return id
}
// 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("not a point on the S256 curve")
}
return p, nil
}
// recoverNodeID computes the public key used to sign the
// given hash from the signature.
func recoverNodeID(hash, sig []byte) (id NodeID, err error) {

18
p2p/discover/node_test.go
View File

@ -133,6 +133,24 @@ func TestNodeID_recover(t *testing.T) {
if pub != recpub {
t.Errorf("recovered wrong pubkey:\ngot: %v\nwant: %v", recpub, pub)
}
ecdsa, err := pub.Pubkey()
if err != nil {
t.Errorf("Pubkey error: %v", err)
}
if !reflect.DeepEqual(ecdsa, &prv.PublicKey) {
t.Errorf("Pubkey mismatch:\n got: %#v\n want: %#v", ecdsa, &prv.PublicKey)
}
}
func TestNodeID_pubkeyBad(t *testing.T) {
ecdsa, err := NodeID{}.Pubkey()
if err == nil {
t.Error("expected error for zero ID")
}
if ecdsa != nil {
t.Error("expected nil result")
}
}
func TestNodeID_distcmp(t *testing.T) {

494
p2p/handshake.go
View File

@ -2,15 +2,18 @@ package p2p
import (
"crypto/ecdsa"
"crypto/elliptic"
"crypto/rand"
"errors"
"fmt"
"hash"
"io"
"net"
"github.com/ethereum/go-ethereum/crypto"
"github.com/ethereum/go-ethereum/crypto/ecies"
"github.com/ethereum/go-ethereum/crypto/secp256k1"
"github.com/ethereum/go-ethereum/crypto/sha3"
"github.com/ethereum/go-ethereum/p2p/discover"
"github.com/ethereum/go-ethereum/rlp"
)
@ -24,27 +27,33 @@ const (
authMsgLen = sigLen + shaLen + pubLen + shaLen + 1
authRespLen = pubLen + shaLen + 1
eciesBytes = 65 + 16 + 32
iHSLen = authMsgLen + eciesBytes // size of the final ECIES payload sent as initiator's handshake
rHSLen = authRespLen + eciesBytes // size of the final ECIES payload sent as receiver's handshake
eciesBytes = 65 + 16 + 32
encAuthMsgLen = authMsgLen + eciesBytes // size of the final ECIES payload sent as initiator's handshake
encAuthRespLen = authRespLen + eciesBytes // size of the final ECIES payload sent as receiver's handshake
)
// conn represents a remote connection after encryption handshake
// and protocol handshake have completed.
//
// The MsgReadWriter is usually layered as follows:
//
// netWrapper (I/O timeouts, thread-safe ReadMsg, WriteMsg)
// rlpxFrameRW (message encoding, encryption, authentication)
// bufio.ReadWriter (buffering)
// net.Conn (network I/O)
//
type conn struct {
*frameRW
MsgReadWriter
*protoHandshake
}
func newConn(fd net.Conn, hs *protoHandshake) *conn {
return &conn{newFrameRW(fd, msgWriteTimeout), hs}
}
// encHandshake represents information about the remote end
// of a connection that is negotiated during the encryption handshake.
type encHandshake struct {
ID discover.NodeID
IngressMAC []byte
EgressMAC []byte
Token []byte
// secrets represents the connection secrets
// which are negotiated during the encryption handshake.
type secrets struct {
RemoteID discover.NodeID
AES, MAC []byte
EgressMAC, IngressMAC hash.Hash
Token []byte
}
// protoHandshake is the RLP structure of the protocol handshake.
@ -68,15 +77,21 @@ func setupConn(fd net.Conn, prv *ecdsa.PrivateKey, our *protoHandshake, dial *di
}
func setupInboundConn(fd net.Conn, prv *ecdsa.PrivateKey, our *protoHandshake) (*conn, error) {
// var remotePubkey []byte
// sessionToken, remotePubkey, err = inboundEncHandshake(fd, prv, nil)
// copy(remoteID[:], remotePubkey)
secrets, err := receiverEncHandshake(fd, prv, nil)
if err != nil {
return nil, fmt.Errorf("encryption handshake failed: %v", err)
}
rw := newFrameRW(fd, msgWriteTimeout)
// Run the protocol handshake using authenticated messages.
rw := newRlpxFrameRW(fd, secrets)
rhs, err := readProtocolHandshake(rw, our)
if err != nil {
return nil, err
}
if rhs.ID != secrets.RemoteID {
return nil, errors.New("node ID in protocol handshake does not match encryption handshake")
}
// TODO: validate that handshake node ID matches
if err := writeProtocolHandshake(rw, our); err != nil {
return nil, fmt.Errorf("protocol write error: %v", err)
}
@ -84,10 +99,13 @@ func setupInboundConn(fd net.Conn, prv *ecdsa.PrivateKey, our *protoHandshake) (
}
func setupOutboundConn(fd net.Conn, prv *ecdsa.PrivateKey, our *protoHandshake, dial *discover.Node) (*conn, error) {
// remoteID = dial.ID
// sessionToken, err = outboundEncHandshake(fd, prv, remoteID[:], nil)
secrets, err := initiatorEncHandshake(fd, prv, dial.ID, nil)
if err != nil {
return nil, fmt.Errorf("encryption handshake failed: %v", err)
}
rw := newFrameRW(fd, msgWriteTimeout)
// Run the protocol handshake using authenticated messages.
rw := newRlpxFrameRW(fd, secrets)
if err := writeProtocolHandshake(rw, our); err != nil {
return nil, fmt.Errorf("protocol write error: %v", err)
}
@ -101,273 +119,256 @@ func setupOutboundConn(fd net.Conn, prv *ecdsa.PrivateKey, our *protoHandshake,
return &conn{rw, rhs}, nil
}
// outboundEncHandshake negotiates a session token on conn.
// encHandshake contains the state of the encryption handshake.
type encHandshake struct {
initiator bool
remoteID discover.NodeID
remotePub *ecies.PublicKey // remote-pubk
initNonce, respNonce []byte // nonce
randomPrivKey *ecies.PrivateKey // ecdhe-random
remoteRandomPub *ecies.PublicKey // ecdhe-random-pubk
}
// secrets is called after the handshake is completed.
// It extracts the connection secrets from the handshake values.
func (h *encHandshake) secrets(auth, authResp []byte) (secrets, error) {
ecdheSecret, err := h.randomPrivKey.GenerateShared(h.remoteRandomPub, sskLen, sskLen)
if err != nil {
return secrets{}, err
}
// derive base secrets from ephemeral key agreement
sharedSecret := crypto.Sha3(ecdheSecret, crypto.Sha3(h.respNonce, h.initNonce))
aesSecret := crypto.Sha3(ecdheSecret, sharedSecret)
s := secrets{
RemoteID: h.remoteID,
AES: aesSecret,
MAC: crypto.Sha3(ecdheSecret, aesSecret),
Token: crypto.Sha3(sharedSecret),
}
// setup sha3 instances for the MACs
mac1 := sha3.NewKeccak256()
mac1.Write(xor(s.MAC, h.respNonce))
mac1.Write(auth)
mac2 := sha3.NewKeccak256()
mac2.Write(xor(s.MAC, h.initNonce))
mac2.Write(authResp)
if h.initiator {
s.EgressMAC, s.IngressMAC = mac1, mac2
} else {
s.EgressMAC, s.IngressMAC = mac2, mac1
}
return s, nil
}
func (h *encHandshake) ecdhShared(prv *ecdsa.PrivateKey) ([]byte, error) {
return ecies.ImportECDSA(prv).GenerateShared(h.remotePub, sskLen, sskLen)
}
// initiatorEncHandshake negotiates a session token on conn.
// it should be called on the dialing side of the connection.
//
// privateKey is the local client's private key
// remotePublicKey is the remote peer's node ID
// sessionToken is the token from a previous session with this node.
func outboundEncHandshake(conn io.ReadWriter, prvKey *ecdsa.PrivateKey, remotePublicKey []byte, sessionToken []byte) (
newSessionToken []byte,
err error,
) {
auth, initNonce, randomPrivKey, err := authMsg(prvKey, remotePublicKey, sessionToken)
// prv is the local client's private key.
// token is the token from a previous session with this node.
func initiatorEncHandshake(conn io.ReadWriter, prv *ecdsa.PrivateKey, remoteID discover.NodeID, token []byte) (s secrets, err error) {
h, err := newInitiatorHandshake(remoteID)
if err != nil {
return nil, err
return s, err
}
auth, err := h.authMsg(prv, token)
if err != nil {
return s, err
}
if _, err = conn.Write(auth); err != nil {
return nil, err
return s, err
}
response := make([]byte, rHSLen)
response := make([]byte, encAuthRespLen)
if _, err = io.ReadFull(conn, response); err != nil {
return nil, err
return s, err
}
recNonce, remoteRandomPubKey, _, err := completeHandshake(response, prvKey)
if err != nil {
return nil, err
if err := h.decodeAuthResp(response, prv); err != nil {
return s, err
}
return newSession(initNonce, recNonce, randomPrivKey, remoteRandomPubKey)
return h.secrets(auth, response)
}
// authMsg creates the initiator handshake.
func authMsg(prvKey *ecdsa.PrivateKey, remotePubKeyS, sessionToken []byte) (
auth, initNonce []byte,
randomPrvKey *ecdsa.PrivateKey,
err error,
) {
// session init, common to both parties
remotePubKey, err := importPublicKey(remotePubKeyS)
if err != nil {
return
func newInitiatorHandshake(remoteID discover.NodeID) (*encHandshake, error) {
// generate random initiator nonce
n := make([]byte, shaLen)
if _, err := rand.Read(n); err != nil {
return nil, err
}
// generate random keypair to use for signing
randpriv, err := ecies.GenerateKey(rand.Reader, crypto.S256(), nil)
if err != nil {
return nil, err
}
rpub, err := remoteID.Pubkey()
if err != nil {
return nil, fmt.Errorf("bad remoteID: %v", err)
}
h := &encHandshake{
initiator: true,
remoteID: remoteID,
remotePub: ecies.ImportECDSAPublic(rpub),
initNonce: n,
randomPrivKey: randpriv,
}
return h, nil
}
var tokenFlag byte // = 0x00
if sessionToken == nil {
// authMsg creates an encrypted initiator handshake message.
func (h *encHandshake) authMsg(prv *ecdsa.PrivateKey, token []byte) ([]byte, error) {
var tokenFlag byte
if token == nil {
// no session token found means we need to generate shared secret.
// ecies shared secret is used as initial session token for new peers
// generate shared key from prv and remote pubkey
if sessionToken, err = ecies.ImportECDSA(prvKey).GenerateShared(ecies.ImportECDSAPublic(remotePubKey), sskLen, sskLen); err != nil {
return
var err error
if token, err = h.ecdhShared(prv); err != nil {
return nil, err
}
// tokenFlag = 0x00 // redundant
} else {
// for known peers, we use stored token from the previous session
tokenFlag = 0x01
}
//E(remote-pubk, S(ecdhe-random, ecdh-shared-secret^nonce) || H(ecdhe-random-pubk) || pubk || nonce || 0x0)
// E(remote-pubk, S(ecdhe-random, token^nonce) || H(ecdhe-random-pubk) || pubk || nonce || 0x1)
// allocate msgLen long message,
var msg []byte = make([]byte, authMsgLen)
initNonce = msg[authMsgLen-shaLen-1 : authMsgLen-1]
if _, err = rand.Read(initNonce); err != nil {
return
}
// create known message
// ecdh-shared-secret^nonce for new peers
// token^nonce for old peers
var sharedSecret = xor(sessionToken, initNonce)
// generate random keypair to use for signing
if randomPrvKey, err = crypto.GenerateKey(); err != nil {
return
}
// sign shared secret (message known to both parties): shared-secret
var signature []byte
// signature = sign(ecdhe-random, shared-secret)
// uses secp256k1.Sign
if signature, err = crypto.Sign(sharedSecret, randomPrvKey); err != nil {
return
// sign known message:
// ecdh-shared-secret^nonce for new peers
// token^nonce for old peers
signed := xor(token, h.initNonce)
signature, err := crypto.Sign(signed, h.randomPrivKey.ExportECDSA())
if err != nil {
return nil, err
}
// message
// signed-shared-secret || H(ecdhe-random-pubk) || pubk || nonce || 0x0
copy(msg, signature) // copy signed-shared-secret
// H(ecdhe-random-pubk)
var randomPubKey64 []byte
if randomPubKey64, err = exportPublicKey(&randomPrvKey.PublicKey); err != nil {
return
}
var pubKey64 []byte
if pubKey64, err = exportPublicKey(&prvKey.PublicKey); err != nil {
return
}
copy(msg[sigLen:sigLen+shaLen], crypto.Sha3(randomPubKey64))
// pubkey copied to the correct segment.
copy(msg[sigLen+shaLen:sigLen+shaLen+pubLen], pubKey64)
// nonce is already in the slice
// stick tokenFlag byte to the end
msg[authMsgLen-1] = tokenFlag
// encode auth message
// signature || sha3(ecdhe-random-pubk) || pubk || nonce || token-flag
msg := make([]byte, authMsgLen)
n := copy(msg, signature)
n += copy(msg[n:], crypto.Sha3(exportPubkey(&h.randomPrivKey.PublicKey)))
n += copy(msg[n:], crypto.FromECDSAPub(&prv.PublicKey)[1:])
n += copy(msg[n:], h.initNonce)
msg[n] = tokenFlag
// encrypt using remote-pubk
// auth = eciesEncrypt(remote-pubk, msg)
if auth, err = crypto.Encrypt(remotePubKey, msg); err != nil {
return
}
return
// encrypt auth message using remote-pubk
return ecies.Encrypt(rand.Reader, h.remotePub, msg, nil, nil)
}
// completeHandshake is called when the initiator receives an
// authentication response (aka receiver handshake). It completes the
// handshake by reading off parameters the remote peer provides needed
// to set up the secure session.
func completeHandshake(auth []byte, prvKey *ecdsa.PrivateKey) (
respNonce []byte,
remoteRandomPubKey *ecdsa.PublicKey,
tokenFlag bool,
err error,
) {
var msg []byte
// they prove that msg is meant for me,
// I prove I possess private key if i can read it
if msg, err = crypto.Decrypt(prvKey, auth); err != nil {
return
// decodeAuthResp decode an encrypted authentication response message.
func (h *encHandshake) decodeAuthResp(auth []byte, prv *ecdsa.PrivateKey) error {
msg, err := crypto.Decrypt(prv, auth)
if err != nil {
return fmt.Errorf("could not decrypt auth response (%v)", err)
}
respNonce = msg[pubLen : pubLen+shaLen]
var remoteRandomPubKeyS = msg[:pubLen]
if remoteRandomPubKey, err = importPublicKey(remoteRandomPubKeyS); err != nil {
return
h.respNonce = msg[pubLen : pubLen+shaLen]
h.remoteRandomPub, err = importPublicKey(msg[:pubLen])
if err != nil {
return err
}
if msg[authRespLen-1] == 0x01 {
tokenFlag = true
}
return
// ignore token flag for now
return nil
}
// inboundEncHandshake negotiates a session token on conn.
// receiverEncHandshake negotiates a session token on conn.
// it should be called on the listening side of the connection.
//
// privateKey is the local client's private key
// sessionToken is the token from a previous session with this node.
func inboundEncHandshake(conn io.ReadWriter, prvKey *ecdsa.PrivateKey, sessionToken []byte) (
token, remotePubKey []byte,
err error,
) {
// we are listening connection. we are responders in the
// handshake. Extract info from the authentication. The initiator
// starts by sending us a handshake that we need to respond to. so
// we read auth message first, then respond.
auth := make([]byte, iHSLen)
// prv is the local client's private key.
// token is the token from a previous session with this node.
func receiverEncHandshake(conn io.ReadWriter, prv *ecdsa.PrivateKey, token []byte) (s secrets, err error) {
// read remote auth sent by initiator.
auth := make([]byte, encAuthMsgLen)
if _, err := io.ReadFull(conn, auth); err != nil {
return nil, nil, err
return s, err
}
response, recNonce, initNonce, remotePubKey, randomPrivKey, remoteRandomPubKey, err := authResp(auth, sessionToken, prvKey)
h, err := decodeAuthMsg(prv, token, auth)
if err != nil {
return nil, nil, err
return s, err
}
if _, err = conn.Write(response); err != nil {
return nil, nil, err
// send auth response
resp, err := h.authResp(prv, token)
if err != nil {
return s, err
}
token, err = newSession(initNonce, recNonce, randomPrivKey, remoteRandomPubKey)
return token, remotePubKey, err
if _, err = conn.Write(resp); err != nil {
return s, err
}
return h.secrets(auth, resp)
}
// authResp is called by peer if it accepted (but not
// initiated) the connection from the remote. It is passed the initiator
// handshake received and the session token belonging to the
// remote initiator.
//
// The first return value is the authentication response (aka receiver
// handshake) that is to be sent to the remote initiator.
func authResp(auth, sessionToken []byte, prvKey *ecdsa.PrivateKey) (
authResp, respNonce, initNonce, remotePubKeyS []byte,
randomPrivKey *ecdsa.PrivateKey,
remoteRandomPubKey *ecdsa.PublicKey,
err error,
) {
// they prove that msg is meant for me,
// I prove I possess private key if i can read it
msg, err := crypto.Decrypt(prvKey, auth)
if err != nil {
return
}
remotePubKeyS = msg[sigLen+shaLen : sigLen+shaLen+pubLen]
remotePubKey, _ := importPublicKey(remotePubKeyS)
var tokenFlag byte
if sessionToken == nil {
// no session token found means we need to generate shared secret.
// ecies shared secret is used as initial session token for new peers
// generate shared key from prv and remote pubkey
if sessionToken, err = ecies.ImportECDSA(prvKey).GenerateShared(ecies.ImportECDSAPublic(remotePubKey), sskLen, sskLen); err != nil {
return
}
// tokenFlag = 0x00 // redundant
} else {
// for known peers, we use stored token from the previous session
tokenFlag = 0x01
}
// the initiator nonce is read off the end of the message
initNonce = msg[authMsgLen-shaLen-1 : authMsgLen-1]
// I prove that i own prv key (to derive shared secret, and read
// nonce off encrypted msg) and that I own shared secret they
// prove they own the private key belonging to ecdhe-random-pubk
// we can now reconstruct the signed message and recover the peers
// pubkey
var signedMsg = xor(sessionToken, initNonce)
var remoteRandomPubKeyS []byte
if remoteRandomPubKeyS, err = secp256k1.RecoverPubkey(signedMsg, msg[:sigLen]); err != nil {
return
}
// convert to ECDSA standard
if remoteRandomPubKey, err = importPublicKey(remoteRandomPubKeyS); err != nil {
return
}
// now we find ourselves a long task too, fill it random
var resp = make([]byte, authRespLen)
// generate shaLen long nonce
respNonce = resp[pubLen : pubLen+shaLen]
if _, err = rand.Read(respNonce); err != nil {
return
}
func decodeAuthMsg(prv *ecdsa.PrivateKey, token []byte, auth []byte) (*encHandshake, error) {
var err error
h := new(encHandshake)
// generate random keypair for session
if randomPrivKey, err = crypto.GenerateKey(); err != nil {
return
}
// responder auth message
// E(remote-pubk, ecdhe-random-pubk || nonce || 0x0)
var randomPubKeyS []byte
if randomPubKeyS, err = exportPublicKey(&randomPrivKey.PublicKey); err != nil {
return
}
copy(resp[:pubLen], randomPubKeyS)
// nonce is already in the slice
resp[authRespLen-1] = tokenFlag
// encrypt using remote-pubk
// auth = eciesEncrypt(remote-pubk, msg)
// why not encrypt with ecdhe-random-remote
if authResp, err = crypto.Encrypt(remotePubKey, resp); err != nil {
return
}
return
}
// newSession is called after the handshake is completed. The
// arguments are values negotiated in the handshake. The return value
// is a new session Token to be remembered for the next time we
// connect with this peer.
func newSession(initNonce, respNonce []byte, privKey *ecdsa.PrivateKey, remoteRandomPubKey *ecdsa.PublicKey) ([]byte, error) {
// 3) Now we can trust ecdhe-random-pubk to derive new keys
//ecdhe-shared-secret = ecdh.agree(ecdhe-random, remote-ecdhe-random-pubk)
pubKey := ecies.ImportECDSAPublic(remoteRandomPubKey)
dhSharedSecret, err := ecies.ImportECDSA(privKey).GenerateShared(pubKey, sskLen, sskLen)
h.randomPrivKey, err = ecies.GenerateKey(rand.Reader, crypto.S256(), nil)
if err != nil {
return nil, err
}
sharedSecret := crypto.Sha3(dhSharedSecret, crypto.Sha3(respNonce, initNonce))
sessionToken := crypto.Sha3(sharedSecret)
return sessionToken, nil
// generate random nonce
h.respNonce = make([]byte, shaLen)
if _, err = rand.Read(h.respNonce); err != nil {
return nil, err
}
msg, err := crypto.Decrypt(prv, auth)
if err != nil {
return nil, fmt.Errorf("could not decrypt auth message (%v)", err)
}
// decode message parameters
// signature || sha3(ecdhe-random-pubk) || pubk || nonce || token-flag
h.initNonce = msg[authMsgLen-shaLen-1 : authMsgLen-1]
copy(h.remoteID[:], msg[sigLen+shaLen:sigLen+shaLen+pubLen])
rpub, err := h.remoteID.Pubkey()
if err != nil {
return nil, fmt.Errorf("bad remoteID: %#v", err)
}
h.remotePub = ecies.ImportECDSAPublic(rpub)
// recover remote random pubkey from signed message.
if token == nil {
// TODO: it is an error if the initiator has a token and we don't. check that.
// no session token means we need to generate shared secret.
// ecies shared secret is used as initial session token for new peers.
// generate shared key from prv and remote pubkey.
if token, err = h.ecdhShared(prv); err != nil {
return nil, err
}
}
signedMsg := xor(token, h.initNonce)
remoteRandomPub, err := secp256k1.RecoverPubkey(signedMsg, msg[:sigLen])
if err != nil {
return nil, err
}
h.remoteRandomPub, _ = importPublicKey(remoteRandomPub)
return h, nil
}
// authResp generates the encrypted authentication response message.
func (h *encHandshake) authResp(prv *ecdsa.PrivateKey, token []byte) ([]byte, error) {
// responder auth message
// E(remote-pubk, ecdhe-random-pubk || nonce || 0x0)
resp := make([]byte, authRespLen)
n := copy(resp, exportPubkey(&h.randomPrivKey.PublicKey))
n += copy(resp[n:], h.respNonce)
if token == nil {
resp[n] = 0
} else {
resp[n] = 1
}
// encrypt using remote-pubk
return ecies.Encrypt(rand.Reader, h.remotePub, resp, nil, nil)
}
// importPublicKey unmarshals 512 bit public keys.
func importPublicKey(pubKey []byte) (pubKeyEC *ecdsa.PublicKey, err error) {
func importPublicKey(pubKey []byte) (*ecies.PublicKey, error) {
var pubKey65 []byte
switch len(pubKey) {
case 64:
@ -378,14 +379,15 @@ func importPublicKey(pubKey []byte) (pubKeyEC *ecdsa.PublicKey, err error) {
default:
return nil, fmt.Errorf("invalid public key length %v (expect 64/65)", len(pubKey))
}
return crypto.ToECDSAPub(pubKey65), nil
// TODO: fewer pointless conversions
return ecies.ImportECDSAPublic(crypto.ToECDSAPub(pubKey65)), nil
}
func exportPublicKey(pubKeyEC *ecdsa.PublicKey) (pubKey []byte, err error) {
if pubKeyEC == nil {
return nil, fmt.Errorf("no ECDSA public key given")
func exportPubkey(pub *ecies.PublicKey) []byte {
if pub == nil {
panic("nil pubkey")
}
return crypto.FromECDSAPub(pubKeyEC)[1:], nil
return elliptic.Marshal(pub.Curve, pub.X, pub.Y)[1:]
}
func xor(one, other []byte) (xor []byte) {

209
p2p/handshake_test.go
View File

@ -2,53 +2,18 @@ package p2p
import (
"bytes"
"crypto/ecdsa"
"crypto/rand"
"fmt"
"net"
"reflect"
"testing"
"time"
"github.com/ethereum/go-ethereum/crypto"
"github.com/ethereum/go-ethereum/crypto/ecies"
"github.com/ethereum/go-ethereum/p2p/discover"
)
func TestPublicKeyEncoding(t *testing.T) {
prv0, _ := crypto.GenerateKey() // = ecdsa.GenerateKey(crypto.S256(), rand.Reader)
pub0 := &prv0.PublicKey
pub0s := crypto.FromECDSAPub(pub0)
pub1, err := importPublicKey(pub0s)
if err != nil {
t.Errorf("%v", err)
}
eciesPub1 := ecies.ImportECDSAPublic(pub1)
if eciesPub1 == nil {
t.Errorf("invalid ecdsa public key")
}
pub1s, err := exportPublicKey(pub1)
if err != nil {
t.Errorf("%v", err)
}
if len(pub1s) != 64 {
t.Errorf("wrong length expect 64, got", len(pub1s))
}
pub2, err := importPublicKey(pub1s)
if err != nil {
t.Errorf("%v", err)
}
pub2s, err := exportPublicKey(pub2)
if err != nil {
t.Errorf("%v", err)
}
if !bytes.Equal(pub1s, pub2s) {
t.Errorf("exports dont match")
}
pub2sEC := crypto.FromECDSAPub(pub2)
if !bytes.Equal(pub0s, pub2sEC) {
t.Errorf("exports dont match")
}
}
func TestSharedSecret(t *testing.T) {
prv0, _ := crypto.GenerateKey() // = ecdsa.GenerateKey(crypto.S256(), rand.Reader)
pub0 := &prv0.PublicKey
@ -69,103 +34,85 @@ func TestSharedSecret(t *testing.T) {
}
}
func TestCryptoHandshake(t *testing.T) {
testCryptoHandshake(newkey(), newkey(), nil, t)
}
func TestCryptoHandshakeWithToken(t *testing.T) {
sessionToken := make([]byte, shaLen)
rand.Read(sessionToken)
testCryptoHandshake(newkey(), newkey(), sessionToken, t)
}
func testCryptoHandshake(prv0, prv1 *ecdsa.PrivateKey, sessionToken []byte, t *testing.T) {
var err error
// pub0 := &prv0.PublicKey
pub1 := &prv1.PublicKey
// pub0s := crypto.FromECDSAPub(pub0)
pub1s := crypto.FromECDSAPub(pub1)
// simulate handshake by feeding output to input
// initiator sends handshake 'auth'
auth, initNonce, randomPrivKey, err := authMsg(prv0, pub1s, sessionToken)
if err != nil {
t.Errorf("%v", err)
}
// t.Logf("-> %v", hexkey(auth))
// receiver reads auth and responds with response
response, remoteRecNonce, remoteInitNonce, _, remoteRandomPrivKey, remoteInitRandomPubKey, err := authResp(auth, sessionToken, prv1)
if err != nil {
t.Errorf("%v", err)
}
// t.Logf("<- %v\n", hexkey(response))
// initiator reads receiver's response and the key exchange completes
recNonce, remoteRandomPubKey, _, err := completeHandshake(response, prv0)
if err != nil {
t.Errorf("completeHandshake error: %v", err)
}
// now both parties should have the same session parameters
initSessionToken, err := newSession(initNonce, recNonce, randomPrivKey, remoteRandomPubKey)
if err != nil {
t.Errorf("newSession error: %v", err)
}
recSessionToken, err := newSession(remoteInitNonce, remoteRecNonce, remoteRandomPrivKey, remoteInitRandomPubKey)
if err != nil {
t.Errorf("newSession error: %v", err)
}
// fmt.Printf("\nauth (%v) %x\n\nresp (%v) %x\n\n", len(auth), auth, len(response), response)
// fmt.Printf("\nauth %x\ninitNonce %x\nresponse%x\nremoteRecNonce %x\nremoteInitNonce %x\nremoteRandomPubKey %x\nrecNonce %x\nremoteInitRandomPubKey %x\ninitSessionToken %x\n\n", auth, initNonce, response, remoteRecNonce, remoteInitNonce, remoteRandomPubKey, recNonce, remoteInitRandomPubKey, initSessionToken)
if !bytes.Equal(initNonce, remoteInitNonce) {
t.Errorf("nonces do not match")
}
if !bytes.Equal(recNonce, remoteRecNonce) {
t.Errorf("receiver nonces do not match")
}
if !bytes.Equal(initSessionToken, recSessionToken) {
t.Errorf("session tokens do not match")
}
}
func TestEncHandshake(t *testing.T) {
defer testlog(t).detach()
prv0, _ := crypto.GenerateKey()
prv1, _ := crypto.GenerateKey()
pub0s, _ := exportPublicKey(&prv0.PublicKey)
pub1s, _ := exportPublicKey(&prv1.PublicKey)
rw0, rw1 := net.Pipe()
tokens := make(chan []byte)
go func() {
token, err := outboundEncHandshake(rw0, prv0, pub1s, nil)
if err != nil {
t.Errorf("outbound side error: %v", err)
for i := 0; i < 20; i++ {
start := time.Now()
if err := testEncHandshake(nil); err != nil {
t.Fatalf("i=%d %v", i, err)
}
tokens <- token
}()
go func() {
token, remotePubkey, err := inboundEncHandshake(rw1, prv1, nil)
if err != nil {
t.Errorf("inbound side error: %v", err)
}
if !bytes.Equal(remotePubkey, pub0s) {
t.Errorf("inbound side returned wrong remote pubkey\n got: %x\n want: %x", remotePubkey, pub0s)
}
tokens <- token
}()
t1, t2 := <-tokens, <-tokens
if !bytes.Equal(t1, t2) {
t.Error("session token mismatch")
t.Logf("(without token) %d %v\n", i+1, time.Since(start))
}
for i := 0; i < 20; i++ {
tok := make([]byte, shaLen)
rand.Reader.Read(tok)
start := time.Now()
if err := testEncHandshake(tok); err != nil {
t.Fatalf("i=%d %v", i, err)
}
t.Logf("(with token) %d %v\n", i+1, time.Since(start))
}
}
func testEncHandshake(token []byte) error {
type result struct {
side string
s secrets
err error
}
var (
prv0, _ = crypto.GenerateKey()
prv1, _ = crypto.GenerateKey()
rw0, rw1 = net.Pipe()
output = make(chan result)
)
go func() {
r := result{side: "initiator"}
defer func() { output <- r }()
pub1s := discover.PubkeyID(&prv1.PublicKey)
r.s, r.err = initiatorEncHandshake(rw0, prv0, pub1s, token)
if r.err != nil {
return
}
id1 := discover.PubkeyID(&prv1.PublicKey)
if r.s.RemoteID != id1 {
r.err = fmt.Errorf("remote ID mismatch: got %v, want: %v", r.s.RemoteID, id1)
}
}()
go func() {
r := result{side: "receiver"}
defer func() { output <- r }()
r.s, r.err = receiverEncHandshake(rw1, prv1, token)
if r.err != nil {
return
}
id0 := discover.PubkeyID(&prv0.PublicKey)
if r.s.RemoteID != id0 {
r.err = fmt.Errorf("remote ID mismatch: got %v, want: %v", r.s.RemoteID, id0)
}
}()
// wait for results from both sides
r1, r2 := <-output, <-output
if r1.err != nil {
return fmt.Errorf("%s side error: %v", r1.side, r1.err)
}
if r2.err != nil {
return fmt.Errorf("%s side error: %v", r2.side, r2.err)
}
// don't compare remote node IDs
r1.s.RemoteID, r2.s.RemoteID = discover.NodeID{}, discover.NodeID{}
// flip MACs on one of them so they compare equal
r1.s.EgressMAC, r1.s.IngressMAC = r1.s.IngressMAC, r1.s.EgressMAC
if !reflect.DeepEqual(r1.s, r2.s) {
return fmt.Errorf("secrets mismatch:\n t1: %#v\n t2: %#v", r1.s, r2.s)
}
return nil
}
func TestSetupConn(t *testing.T) {

187
p2p/message.go
View File

@ -1,14 +1,11 @@
package p2p
import (
"bufio"
"bytes"
"encoding/binary"
"errors"
"fmt"
"io"
"io/ioutil"
"math/big"
"net"
"sync"
"sync/atomic"
@ -18,28 +15,6 @@ import (
"github.com/ethereum/go-ethereum/rlp"
)
// parameters for frameRW
const (
// maximum time allowed for reading a message header.
// this is effectively the amount of time a connection can be idle.
frameReadTimeout = 1 * time.Minute
// maximum time allowed for reading the payload data of a message.
// this is shorter than (and distinct from) frameReadTimeout because
// the connection is not considered idle while a message is transferred.
// this also limits the payload size of messages to how much the connection
// can transfer within the timeout.
payloadReadTimeout = 5 * time.Second
// maximum amount of time allowed for writing a complete message.
msgWriteTimeout = 5 * time.Second
// messages smaller than this many bytes will be read at
// once before passing them to a protocol. this increases
// concurrency in the processing.
wholePayloadSize = 64 * 1024
)
// Msg defines the structure of a p2p message.
//
// Note that a Msg can only be sent once since the Payload reader is
@ -55,19 +30,8 @@ type Msg struct {
// NewMsg creates an RLP-encoded message with the given code.
func NewMsg(code uint64, params ...interface{}) Msg {
buf := new(bytes.Buffer)
for _, p := range params {
buf.Write(ethutil.Encode(p))
}
return Msg{Code: code, Size: uint32(buf.Len()), Payload: buf}
}
func encodePayload(params ...interface{}) []byte {
buf := new(bytes.Buffer)
for _, p := range params {
buf.Write(ethutil.Encode(p))
}
return buf.Bytes()
p := bytes.NewReader(ethutil.Encode(params))
return Msg{Code: code, Size: uint32(p.Len()), Payload: p}
}
// Decode parse the RLP content of a message into
@ -75,8 +39,7 @@ func encodePayload(params ...interface{}) []byte {
//
// For the decoding rules, please see package rlp.
func (msg Msg) Decode(val interface{}) error {
s := rlp.NewListStream(msg.Payload, uint64(msg.Size))
if err := s.Decode(val); err != nil {
if err := rlp.Decode(msg.Payload, val); err != nil {
return newPeerError(errInvalidMsg, "(code %#x) (size %d) %v", msg.Code, msg.Size, err)
}
return nil
@ -119,138 +82,28 @@ func EncodeMsg(w MsgWriter, code uint64, data ...interface{}) error {
return w.WriteMsg(NewMsg(code, data...))
}
// frameRW is a MsgReadWriter that reads and writes devp2p message frames.
// As required by the interface, ReadMsg and WriteMsg can be called from
// multiple goroutines.
type frameRW struct {
net.Conn // make Conn methods available. be careful.
bufconn *bufio.ReadWriter
// netWrapper wrapsa MsgReadWriter with locks around
// ReadMsg/WriteMsg and applies read/write deadlines.
type netWrapper struct {
rmu, wmu sync.Mutex
// this channel is used to 'lend' bufconn to a caller of ReadMsg
// until the message payload has been consumed. the channel
// receives a value when EOF is reached on the payload, unblocking
// a pending call to ReadMsg.
rsync chan struct{}
// this mutex guards writes to bufconn.
writeMu sync.Mutex
rtimeout, wtimeout time.Duration
conn net.Conn
wrapped MsgReadWriter
}
func newFrameRW(conn net.Conn, timeout time.Duration) *frameRW {
rsync := make(chan struct{}, 1)
rsync <- struct{}{}
return &frameRW{
Conn: conn,
bufconn: bufio.NewReadWriter(bufio.NewReader(conn), bufio.NewWriter(conn)),
rsync: rsync,
}
func (rw *netWrapper) ReadMsg() (Msg, error) {
rw.rmu.Lock()
defer rw.rmu.Unlock()
rw.conn.SetReadDeadline(time.Now().Add(rw.rtimeout))
return rw.wrapped.ReadMsg()
}
var magicToken = []byte{34, 64, 8, 145}
func (rw *frameRW) WriteMsg(msg Msg) error {
rw.writeMu.Lock()
defer rw.writeMu.Unlock()
rw.SetWriteDeadline(time.Now().Add(msgWriteTimeout))
if err := writeMsg(rw.bufconn, msg); err != nil {
return err
}
return rw.bufconn.Flush()
}
func writeMsg(w io.Writer, msg Msg) error {
// TODO: handle case when Size + len(code) + len(listhdr) overflows uint32
code := ethutil.Encode(uint32(msg.Code))
listhdr := makeListHeader(msg.Size + uint32(len(code)))
payloadLen := uint32(len(listhdr)) + uint32(len(code)) + msg.Size
start := make([]byte, 8)
copy(start, magicToken)
binary.BigEndian.PutUint32(start[4:], payloadLen)
for _, b := range [][]byte{start, listhdr, code} {
if _, err := w.Write(b); err != nil {
return err
}
}
_, err := io.CopyN(w, msg.Payload, int64(msg.Size))
return err
}
func makeListHeader(length uint32) []byte {
if length < 56 {
return []byte{byte(length + 0xc0)}
}
enc := big.NewInt(int64(length)).Bytes()
lenb := byte(len(enc)) + 0xf7
return append([]byte{lenb}, enc...)
}
func (rw *frameRW) ReadMsg() (msg Msg, err error) {
<-rw.rsync // wait until bufconn is ours
rw.SetReadDeadline(time.Now().Add(frameReadTimeout))
// read magic and payload size
start := make([]byte, 8)
if _, err = io.ReadFull(rw.bufconn, start); err != nil {
return msg, err
}
if !bytes.HasPrefix(start, magicToken) {
return msg, fmt.Errorf("bad magic token %x", start[:4])
}
size := binary.BigEndian.Uint32(start[4:])
// decode start of RLP message to get the message code
posr := &postrack{rw.bufconn, 0}
s := rlp.NewStream(posr)
if _, err := s.List(); err != nil {
return msg, err
}
msg.Code, err = s.Uint()
if err != nil {
return msg, err
}
msg.Size = size - posr.p
rw.SetReadDeadline(time.Now().Add(payloadReadTimeout))
if msg.Size <= wholePayloadSize {
// msg is small, read all of it and move on to the next message.
pbuf := make([]byte, msg.Size)
if _, err := io.ReadFull(rw.bufconn, pbuf); err != nil {
return msg, err
}
rw.rsync <- struct{}{} // bufconn is available again
msg.Payload = bytes.NewReader(pbuf)
} else {
// lend bufconn to the caller until it has
// consumed the payload. eofSignal will send a value
// on rw.rsync when EOF is reached.
pr := &eofSignal{rw.bufconn, msg.Size, rw.rsync}
msg.Payload = pr
}
return msg, nil
}
// postrack wraps an rlp.ByteReader with a position counter.
type postrack struct {
r rlp.ByteReader
p uint32
}
func (r *postrack) Read(buf []byte) (int, error) {
n, err := r.r.Read(buf)
r.p += uint32(n)
return n, err
}
func (r *postrack) ReadByte() (byte, error) {
b, err := r.r.ReadByte()
if err == nil {
r.p++
}
return b, err
func (rw *netWrapper) WriteMsg(msg Msg) error {
rw.wmu.Lock()
defer rw.wmu.Unlock()
rw.conn.SetWriteDeadline(time.Now().Add(rw.wtimeout))
return rw.wrapped.WriteMsg(msg)
}
// eofSignal wraps a reader with eof signaling. the eof channel is

62
p2p/message_test.go
View File

@ -2,10 +2,12 @@ package p2p
import (
"bytes"
"encoding/hex"
"fmt"
"io"
"io/ioutil"
"runtime"
"strings"
"testing"
"time"
)
@ -15,62 +17,16 @@ func TestNewMsg(t *testing.T) {
if msg.Code != 3 {
t.Errorf("incorrect code %d, want %d", msg.Code)
}
if msg.Size != 5 {
t.Errorf("incorrect size %d, want %d", msg.Size, 5)
expect := unhex("c50183303030")
if msg.Size != uint32(len(expect)) {
t.Errorf("incorrect size %d, want %d", msg.Size, len(expect))
}
pl, _ := ioutil.ReadAll(msg.Payload)
expect := []byte{0x01, 0x83, 0x30, 0x30, 0x30}
if !bytes.Equal(pl, expect) {
t.Errorf("incorrect payload content, got %x, want %x", pl, expect)
}
}
// func TestEncodeDecodeMsg(t *testing.T) {
// msg := NewMsg(3, 1, "000")
// buf := new(bytes.Buffer)
// if err := writeMsg(buf, msg); err != nil {
// t.Fatalf("encodeMsg error: %v", err)
// }
// // t.Logf("encoded: %x", buf.Bytes())
// decmsg, err := readMsg(buf)
// if err != nil {
// t.Fatalf("readMsg error: %v", err)
// }
// if decmsg.Code != 3 {
// t.Errorf("incorrect code %d, want %d", decmsg.Code, 3)
// }
// if decmsg.Size != 5 {
// t.Errorf("incorrect size %d, want %d", decmsg.Size, 5)
// }
// var data struct {
// I uint
// S string
// }
// if err := decmsg.Decode(&data); err != nil {
// t.Fatalf("Decode error: %v", err)
// }
// if data.I != 1 {
// t.Errorf("incorrect data.I: got %v, expected %d", data.I, 1)
// }
// if data.S != "000" {
// t.Errorf("incorrect data.S: got %q, expected %q", data.S, "000")
// }
// }
// func TestDecodeRealMsg(t *testing.T) {
// data := ethutil.Hex2Bytes("2240089100000080f87e8002b5457468657265756d282b2b292f5065657220536572766572204f6e652f76302e372e382f52656c656173652f4c696e75782f672b2bc082765fb84086dd80b7aefd6a6d2e3b93f4f300a86bfb6ef7bdc97cb03f793db6bb")
// msg, err := readMsg(bytes.NewReader(data))
// if err != nil {
// t.Fatalf("unexpected error: %v", err)
// }
// if msg.Code != 0 {
// t.Errorf("incorrect code %d, want %d", msg.Code, 0)
// }
// }
func ExampleMsgPipe() {
rw1, rw2 := MsgPipe()
go func() {
@ -185,3 +141,11 @@ func TestEOFSignal(t *testing.T) {
default:
}
}
func unhex(str string) []byte {
b, err := hex.DecodeString(strings.Replace(str, "\n", "", -1))
if err != nil {
panic(fmt.Sprintf("invalid hex string: %q", str))
}
return b
}

28
p2p/peer.go
View File

@ -20,8 +20,8 @@ const (
baseProtocolLength = uint64(16)
baseProtocolMaxMsgSize = 10 * 1024 * 1024
disconnectGracePeriod = 2 * time.Second
pingInterval = 15 * time.Second
disconnectGracePeriod = 2 * time.Second
)
const (
@ -40,6 +40,7 @@ type Peer struct {
// Use them to display messages related to the peer.
*logger.Logger
conn net.Conn
rw *conn
running map[string]*protoRW
@ -52,8 +53,9 @@ type Peer struct {
// NewPeer returns a peer for testing purposes.
func NewPeer(id discover.NodeID, name string, caps []Cap) *Peer {
pipe, _ := net.Pipe()
conn := newConn(pipe, &protoHandshake{ID: id, Name: name, Caps: caps})
peer := newPeer(conn, nil)
msgpipe, _ := MsgPipe()
conn := &conn{msgpipe, &protoHandshake{ID: id, Name: name, Caps: caps}}
peer := newPeer(pipe, conn, nil)
close(peer.closed) // ensures Disconnect doesn't block
return peer
}
@ -76,12 +78,12 @@ func (p *Peer) Caps() []Cap {
// RemoteAddr returns the remote address of the network connection.
func (p *Peer) RemoteAddr() net.Addr {
return p.rw.RemoteAddr()
return p.conn.RemoteAddr()
}
// LocalAddr returns the local address of the network connection.
func (p *Peer) LocalAddr() net.Addr {
return p.rw.LocalAddr()
return p.conn.LocalAddr()
}
// Disconnect terminates the peer connection with the given reason.
@ -98,10 +100,11 @@ func (p *Peer) String() string {
return fmt.Sprintf("Peer %.8x %v", p.rw.ID[:], p.RemoteAddr())
}
func newPeer(conn *conn, protocols []Protocol) *Peer {
logtag := fmt.Sprintf("Peer %.8x %v", conn.ID[:], conn.RemoteAddr())
func newPeer(fd net.Conn, conn *conn, protocols []Protocol) *Peer {
logtag := fmt.Sprintf("Peer %.8x %v", conn.ID[:], fd.RemoteAddr())
p := &Peer{
Logger: logger.NewLogger(logtag),
conn: fd,
rw: conn,
running: matchProtocols(protocols, conn.Caps, conn),
disc: make(chan DiscReason),
@ -138,7 +141,7 @@ loop:
// We rely on protocols to abort if there is a write error. It
// might be more robust to handle them here as well.
p.DebugDetailf("Read error: %v\n", err)
p.rw.Close()
p.conn.Close()
return DiscNetworkError
case err := <-p.protoErr:
reason = discReasonForError(err)
@ -161,18 +164,19 @@ func (p *Peer) politeDisconnect(reason DiscReason) {
EncodeMsg(p.rw, discMsg, uint(reason))
// Wait for the other side to close the connection.
// Discard any data that they send until then.
io.Copy(ioutil.Discard, p.rw)
io.Copy(ioutil.Discard, p.conn)
close(done)
}()
select {
case <-done:
case <-time.After(disconnectGracePeriod):
}
p.rw.Close()
p.conn.Close()
}
func (p *Peer) readLoop() error {
for {
p.conn.SetDeadline(time.Now().Add(frameReadTimeout))
msg, err := p.rw.ReadMsg()
if err != nil {
return err
@ -190,12 +194,12 @@ func (p *Peer) handle(msg Msg) error {
msg.Discard()
go EncodeMsg(p.rw, pongMsg)
case msg.Code == discMsg:
var reason DiscReason
var reason [1]DiscReason
// no need to discard or for error checking, we'll close the
// connection after this.
rlp.Decode(msg.Payload, &reason)
p.Disconnect(DiscRequested)
return discRequestedError(reason)
return discRequestedError(reason[0])
case msg.Code < baseProtocolLength:
// ignore other base protocol messages
return msg.Discard()

75
p2p/peer_test.go
View File

@ -3,6 +3,7 @@ package p2p
import (
"bytes"
"fmt"
"io"
"io/ioutil"
"net"
"reflect"
@ -29,8 +30,8 @@ var discard = Protocol{
},
}
func testPeer(protos []Protocol) (*conn, *Peer, <-chan DiscReason) {
fd1, fd2 := net.Pipe()
func testPeer(protos []Protocol) (io.Closer, *conn, *Peer, <-chan DiscReason) {
fd1, _ := net.Pipe()
hs1 := &protoHandshake{ID: randomID(), Version: baseProtocolVersion}
hs2 := &protoHandshake{ID: randomID(), Version: baseProtocolVersion}
for _, p := range protos {
@ -38,11 +39,12 @@ func testPeer(protos []Protocol) (*conn, *Peer, <-chan DiscReason) {
hs2.Caps = append(hs2.Caps, p.cap())
}
peer := newPeer(newConn(fd1, hs1), protos)
p1, p2 := MsgPipe()
peer := newPeer(fd1, &conn{p1, hs1}, protos)
errc := make(chan DiscReason, 1)
go func() { errc <- peer.run() }()
return newConn(fd2, hs2), peer, errc
return p1, &conn{p2, hs2}, peer, errc
}
func TestPeerProtoReadMsg(t *testing.T) {
@ -67,8 +69,8 @@ func TestPeerProtoReadMsg(t *testing.T) {
},
}
rw, _, errc := testPeer([]Protocol{proto})
defer rw.Close()
closer, rw, _, errc := testPeer([]Protocol{proto})
defer closer.Close()
EncodeMsg(rw, baseProtocolLength+2, 1)
EncodeMsg(rw, baseProtocolLength+3, 2)
@ -83,41 +85,6 @@ func TestPeerProtoReadMsg(t *testing.T) {
}
}
func TestPeerProtoReadLargeMsg(t *testing.T) {
defer testlog(t).detach()
msgsize := uint32(10 * 1024 * 1024)
done := make(chan struct{})
proto := Protocol{
Name: "a",
Length: 5,
Run: func(peer *Peer, rw MsgReadWriter) error {
msg, err := rw.ReadMsg()
if err != nil {
t.Errorf("read error: %v", err)
}
if msg.Size != msgsize+4 {
t.Errorf("incorrect msg.Size, got %d, expected %d", msg.Size, msgsize)
}
msg.Discard()
close(done)
return nil
},
}
rw, _, errc := testPeer([]Protocol{proto})
defer rw.Close()
EncodeMsg(rw, 18, make([]byte, msgsize))
select {
case <-done:
case err := <-errc:
t.Errorf("peer returned: %v", err)
case <-time.After(2 * time.Second):
t.Errorf("receive timeout")
}
}
func TestPeerProtoEncodeMsg(t *testing.T) {
defer testlog(t).detach()
@ -134,8 +101,8 @@ func TestPeerProtoEncodeMsg(t *testing.T) {
return nil
},
}
rw, _, _ := testPeer([]Protocol{proto})
defer rw.Close()
closer, rw, _, _ := testPeer([]Protocol{proto})
defer closer.Close()
if err := expectMsg(rw, 17, []string{"foo", "bar"}); err != nil {
t.Error(err)
@ -145,8 +112,8 @@ func TestPeerProtoEncodeMsg(t *testing.T) {
func TestPeerWriteForBroadcast(t *testing.T) {
defer testlog(t).detach()
rw, peer, peerErr := testPeer([]Protocol{discard})
defer rw.Close()
closer, rw, peer, peerErr := testPeer([]Protocol{discard})
defer closer.Close()
// test write errors
if err := peer.writeProtoMsg("b", NewMsg(3)); err == nil {
@ -181,8 +148,8 @@ func TestPeerWriteForBroadcast(t *testing.T) {
func TestPeerPing(t *testing.T) {
defer testlog(t).detach()
rw, _, _ := testPeer(nil)
defer rw.Close()
closer, rw, _, _ := testPeer(nil)
defer closer.Close()
if err := EncodeMsg(rw, pingMsg); err != nil {
t.Fatal(err)
}
@ -194,15 +161,15 @@ func TestPeerPing(t *testing.T) {
func TestPeerDisconnect(t *testing.T) {
defer testlog(t).detach()
rw, _, disc := testPeer(nil)
defer rw.Close()
closer, rw, _, disc := testPeer(nil)
defer closer.Close()
if err := EncodeMsg(rw, discMsg, DiscQuitting); err != nil {
t.Fatal(err)
}
if err := expectMsg(rw, discMsg, []interface{}{DiscRequested}); err != nil {
t.Error(err)
}
rw.Close() // make test end faster
closer.Close() // make test end faster
if reason := <-disc; reason != DiscRequested {
t.Errorf("run returned wrong reason: got %v, want %v", reason, DiscRequested)
}
@ -244,13 +211,9 @@ func expectMsg(r MsgReader, code uint64, content interface{}) error {
if err != nil {
panic("content encode error: " + err.Error())
}
// skip over list header in encoded value. this is temporary.
contentEncR := bytes.NewReader(contentEnc)
if k, _, err := rlp.NewStream(contentEncR).Kind(); k != rlp.List || err != nil {
panic("content must encode as RLP list")
if int(msg.Size) != len(contentEnc) {
return fmt.Errorf("message size mismatch: got %d, want %d", msg.Size, len(contentEnc))
}
contentEnc = contentEnc[len(contentEnc)-contentEncR.Len():]
actualContent, err := ioutil.ReadAll(msg.Payload)
if err != nil {
return err

174
p2p/rlpx.go Normal file
View File

@ -0,0 +1,174 @@
package p2p
import (
"bytes"
"crypto/aes"
"crypto/cipher"
"crypto/hmac"
"errors"
"hash"
"io"
"github.com/ethereum/go-ethereum/rlp"
)
var (
// this is used in place of actual frame header data.
// TODO: replace this when Msg contains the protocol type code.
zeroHeader = []byte{0xC2, 0x80, 0x80}
// sixteen zero bytes
zero16 = make([]byte, 16)
maxUint24 = ^uint32(0) >> 8
)
// rlpxFrameRW implements a simplified version of RLPx framing.
// chunked messages are not supported and all headers are equal to
// zeroHeader.
//
// rlpxFrameRW is not safe for concurrent use from multiple goroutines.
type rlpxFrameRW struct {
conn io.ReadWriter
enc cipher.Stream
dec cipher.Stream
macCipher cipher.Block
egressMAC hash.Hash
ingressMAC hash.Hash
}
func newRlpxFrameRW(conn io.ReadWriter, s secrets) *rlpxFrameRW {
macc, err := aes.NewCipher(s.MAC)
if err != nil {
panic("invalid MAC secret: " + err.Error())
}
encc, err := aes.NewCipher(s.AES)
if err != nil {
panic("invalid AES secret: " + err.Error())
}
// we use an all-zeroes IV for AES because the key used
// for encryption is ephemeral.
iv := make([]byte, encc.BlockSize())
return &rlpxFrameRW{
conn: conn,
enc: cipher.NewCTR(encc, iv),
dec: cipher.NewCTR(encc, iv),
macCipher: macc,
egressMAC: s.EgressMAC,
ingressMAC: s.IngressMAC,
}
}
func (rw *rlpxFrameRW) WriteMsg(msg Msg) error {
ptype, _ := rlp.EncodeToBytes(msg.Code)
// write header
headbuf := make([]byte, 32)
fsize := uint32(len(ptype)) + msg.Size
if fsize > maxUint24 {
return errors.New("message size overflows uint24")
}
putInt24(fsize, headbuf) // TODO: check overflow
copy(headbuf[3:], zeroHeader)
rw.enc.XORKeyStream(headbuf[:16], headbuf[:16]) // first half is now encrypted
// write header MAC
copy(headbuf[16:], updateMAC(rw.egressMAC, rw.macCipher, headbuf[:16]))
if _, err := rw.conn.Write(headbuf); err != nil {
return err
}
// write encrypted frame, updating the egress MAC hash with
// the data written to conn.
tee := cipher.StreamWriter{S: rw.enc, W: io.MultiWriter(rw.conn, rw.egressMAC)}
if _, err := tee.Write(ptype); err != nil {
return err
}
if _, err := io.Copy(tee, msg.Payload); err != nil {
return err
}
if padding := fsize % 16; padding > 0 {
if _, err := tee.Write(zero16[:16-padding]); err != nil {
return err
}
}
// write frame MAC. egress MAC hash is up to date because
// frame content was written to it as well.
fmacseed := rw.egressMAC.Sum(nil)
mac := updateMAC(rw.egressMAC, rw.macCipher, fmacseed)
_, err := rw.conn.Write(mac)
return err
}
func (rw *rlpxFrameRW) ReadMsg() (msg Msg, err error) {
// read the header
headbuf := make([]byte, 32)
if _, err := io.ReadFull(rw.conn, headbuf); err != nil {
return msg, err
}
// verify header mac
shouldMAC := updateMAC(rw.ingressMAC, rw.macCipher, headbuf[:16])
if !hmac.Equal(shouldMAC, headbuf[16:]) {
return msg, errors.New("bad header MAC")
}
rw.dec.XORKeyStream(headbuf[:16], headbuf[:16]) // first half is now decrypted
fsize := readInt24(headbuf)
// ignore protocol type for now
// read the frame content
var rsize = fsize // frame size rounded up to 16 byte boundary
if padding := fsize % 16; padding > 0 {
rsize += 16 - padding
}
framebuf := make([]byte, rsize)
if _, err := io.ReadFull(rw.conn, framebuf); err != nil {
return msg, err
}
// read and validate frame MAC. we can re-use headbuf for that.
rw.ingressMAC.Write(framebuf)
fmacseed := rw.ingressMAC.Sum(nil)
if _, err := io.ReadFull(rw.conn, headbuf[:16]); err != nil {
return msg, err
}
shouldMAC = updateMAC(rw.ingressMAC, rw.macCipher, fmacseed)
if !hmac.Equal(shouldMAC, headbuf[:16]) {
return msg, errors.New("bad frame MAC")
}
// decrypt frame content
rw.dec.XORKeyStream(framebuf, framebuf)
// decode message code
content := bytes.NewReader(framebuf[:fsize])
if err := rlp.Decode(content, &msg.Code); err != nil {
return msg, err
}
msg.Size = uint32(content.Len())
msg.Payload = content
return msg, nil
}
// updateMAC reseeds the given hash with encrypted seed.
// it returns the first 16 bytes of the hash sum after seeding.
func updateMAC(mac hash.Hash, block cipher.Block, seed []byte) []byte {
aesbuf := make([]byte, aes.BlockSize)
block.Encrypt(aesbuf, mac.Sum(nil))
for i := range aesbuf {
aesbuf[i] ^= seed[i]
}
mac.Write(aesbuf)
return mac.Sum(nil)[:16]
}
func readInt24(b []byte) uint32 {
return uint32(b[2]) | uint32(b[1])<<8 | uint32(b[0])<<16
}
func putInt24(v uint32, b []byte) {
b[0] = byte(v >> 16)
b[1] = byte(v >> 8)
b[2] = byte(v)
}

124
p2p/rlpx_test.go Normal file
View File

@ -0,0 +1,124 @@
package p2p
import (
"bytes"
"crypto/rand"
"io/ioutil"
"strings"
"testing"
"github.com/ethereum/go-ethereum/crypto"
"github.com/ethereum/go-ethereum/crypto/sha3"
"github.com/ethereum/go-ethereum/rlp"
)
func TestRlpxFrameFake(t *testing.T) {
buf := new(bytes.Buffer)
hash := fakeHash([]byte{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})
rw := newRlpxFrameRW(buf, secrets{
AES: crypto.Sha3(),
MAC: crypto.Sha3(),
IngressMAC: hash,
EgressMAC: hash,
})
golden := unhex(`
00828ddae471818bb0bfa6b551d1cb42
01010101010101010101010101010101
ba628a4ba590cb43f7848f41c4382885
01010101010101010101010101010101
`)
// Check WriteMsg. This puts a message into the buffer.
if err := EncodeMsg(rw, 8, 1, 2, 3, 4); err != nil {
t.Fatalf("WriteMsg error: %v", err)
}
written := buf.Bytes()
if !bytes.Equal(written, golden) {
t.Fatalf("output mismatch:\n got: %x\n want: %x", written, golden)
}
// Check ReadMsg. It reads the message encoded by WriteMsg, which
// is equivalent to the golden message above.
msg, err := rw.ReadMsg()
if err != nil {
t.Fatalf("ReadMsg error: %v", err)
}
if msg.Size != 5 {
t.Errorf("msg size mismatch: got %d, want %d", msg.Size, 5)
}
if msg.Code != 8 {
t.Errorf("msg code mismatch: got %d, want %d", msg.Code, 8)
}
payload, _ := ioutil.ReadAll(msg.Payload)
wantPayload := unhex("C401020304")
if !bytes.Equal(payload, wantPayload) {
t.Errorf("msg payload mismatch:\ngot %x\nwant %x", payload, wantPayload)
}
}
type fakeHash []byte
func (fakeHash) Write(p []byte) (int, error) { return len(p), nil }
func (fakeHash) Reset() {}
func (fakeHash) BlockSize() int { return 0 }
func (h fakeHash) Size() int { return len(h) }
func (h fakeHash) Sum(b []byte) []byte { return append(b, h...) }
func TestRlpxFrameRW(t *testing.T) {
var (
aesSecret = make([]byte, 16)
macSecret = make([]byte, 16)
egressMACinit = make([]byte, 32)
ingressMACinit = make([]byte, 32)
)
for _, s := range [][]byte{aesSecret, macSecret, egressMACinit, ingressMACinit} {
rand.Read(s)
}
conn := new(bytes.Buffer)
s1 := secrets{
AES: aesSecret,
MAC: macSecret,
EgressMAC: sha3.NewKeccak256(),
IngressMAC: sha3.NewKeccak256(),
}
s1.EgressMAC.Write(egressMACinit)
s1.IngressMAC.Write(ingressMACinit)
rw1 := newRlpxFrameRW(conn, s1)
s2 := secrets{
AES: aesSecret,
MAC: macSecret,
EgressMAC: sha3.NewKeccak256(),
IngressMAC: sha3.NewKeccak256(),
}
s2.EgressMAC.Write(ingressMACinit)
s2.IngressMAC.Write(egressMACinit)
rw2 := newRlpxFrameRW(conn, s2)
// send some messages
for i := 0; i < 10; i++ {
// write message into conn buffer
wmsg := []interface{}{"foo", "bar", strings.Repeat("test", i)}
err := EncodeMsg(rw1, uint64(i), wmsg...)
if err != nil {
t.Fatalf("WriteMsg error (i=%d): %v", i, err)
}
// read message that rw1 just wrote
msg, err := rw2.ReadMsg()
if err != nil {
t.Fatalf("ReadMsg error (i=%d): %v", i, err)
}
if msg.Code != uint64(i) {
t.Fatalf("msg code mismatch: got %d, want %d", msg.Code, i)
}
payload, _ := ioutil.ReadAll(msg.Payload)
wantPayload, _ := rlp.EncodeToBytes(wmsg)
if !bytes.Equal(payload, wantPayload) {
t.Fatalf("msg payload mismatch:\ngot %x\nwant %x", payload, wantPayload)
}
}
}

81
p2p/server.go
View File

@ -10,15 +10,24 @@ import (
"sync"
"time"
"github.com/ethereum/go-ethereum/ethutil"
"github.com/ethereum/go-ethereum/logger"
"github.com/ethereum/go-ethereum/p2p/discover"
"github.com/ethereum/go-ethereum/p2p/nat"
)
const (
handshakeTimeout = 5 * time.Second
defaultDialTimeout = 10 * time.Second
refreshPeersInterval = 30 * time.Second
// total timeout for encryption handshake and protocol
// handshake in both directions.
handshakeTimeout = 5 * time.Second
// maximum time allowed for reading a complete message.
// this is effectively the amount of time a connection can be idle.
frameReadTimeout = 1 * time.Minute
// maximum amount of time allowed for writing a complete message.
frameWriteTimeout = 5 * time.Second
)
var srvlog = logger.NewLogger("P2P Server")
@ -57,10 +66,6 @@ type Server struct {
// each peer.
Protocols []Protocol
// If Blacklist is set to a non-nil value, the given Blacklist
// is used to verify peer connections.
Blacklist Blacklist
// If ListenAddr is set to a non-nil address, the server
// will listen for incoming connections.
//
@ -135,7 +140,7 @@ func (srv *Server) SuggestPeer(n *discover.Node) {
func (srv *Server) Broadcast(protocol string, code uint64, data ...interface{}) {
var payload []byte
if data != nil {
payload = encodePayload(data...)
payload = ethutil.Encode(data)
}
srv.lock.RLock()
defer srv.lock.RUnlock()
@ -174,9 +179,6 @@ func (srv *Server) Start() (err error) {
if srv.setupFunc == nil {
srv.setupFunc = setupConn
}
if srv.Blacklist == nil {
srv.Blacklist = NewBlacklist()
}
// node table
ntab, err := discover.ListenUDP(srv.PrivateKey, srv.ListenAddr, srv.NAT)
@ -365,7 +367,12 @@ func (srv *Server) startPeer(fd net.Conn, dest *discover.Node) {
srvlog.Debugf("Handshake with %v failed: %v", fd.RemoteAddr(), err)
return
}
p := newPeer(conn, srv.Protocols)
conn.MsgReadWriter = &netWrapper{
wrapped: conn.MsgReadWriter,
conn: fd, rtimeout: frameReadTimeout, wtimeout: frameWriteTimeout,
}
p := newPeer(fd, conn, srv.Protocols)
if ok, reason := srv.addPeer(conn.ID, p); !ok {
srvlog.DebugDetailf("Not adding %v (%v)\n", p, reason)
p.politeDisconnect(reason)
@ -375,7 +382,7 @@ func (srv *Server) startPeer(fd net.Conn, dest *discover.Node) {
srvlog.Debugf("Added %v\n", p)
srvjslog.LogJson(&logger.P2PConnected{
RemoteId: fmt.Sprintf("%x", conn.ID[:]),
RemoteAddress: conn.RemoteAddr().String(),
RemoteAddress: fd.RemoteAddr().String(),
RemoteVersionString: conn.Name,
NumConnections: srv.PeerCount(),
})
@ -403,8 +410,6 @@ func (srv *Server) addPeer(id discover.NodeID, p *Peer) (bool, DiscReason) {
return false, DiscTooManyPeers
case srv.peers[id] != nil:
return false, DiscAlreadyConnected
case srv.Blacklist.Exists(id[:]):
return false, DiscUselessPeer
case id == srv.ntab.Self():
return false, DiscSelf
}
@ -418,53 +423,3 @@ func (srv *Server) removePeer(p *Peer) {
srv.lock.Unlock()
srv.peerWG.Done()
}
type Blacklist interface {
Get([]byte) (bool, error)
Put([]byte) error
Delete([]byte) error
Exists(pubkey []byte) (ok bool)
}
type BlacklistMap struct {
blacklist map[string]bool
lock sync.RWMutex
}
func NewBlacklist() *BlacklistMap {
return &BlacklistMap{
blacklist: make(map[string]bool),
}
}
func (self *BlacklistMap) Get(pubkey []byte) (bool, error) {
self.lock.RLock()
defer self.lock.RUnlock()
v, ok := self.blacklist[string(pubkey)]
var err error
if !ok {
err = fmt.Errorf("not found")
}
return v, err
}
func (self *BlacklistMap) Exists(pubkey []byte) (ok bool) {
self.lock.RLock()
defer self.lock.RUnlock()
_, ok = self.blacklist[string(pubkey)]
return
}
func (self *BlacklistMap) Put(pubkey []byte) error {
self.lock.Lock()
defer self.lock.Unlock()
self.blacklist[string(pubkey)] = true
return nil
}
func (self *BlacklistMap) Delete(pubkey []byte) error {
self.lock.Lock()
defer self.lock.Unlock()
delete(self.blacklist, string(pubkey))
return nil
}

13
p2p/server_test.go
View File

@ -11,6 +11,7 @@ import (
"time"
"github.com/ethereum/go-ethereum/crypto"
"github.com/ethereum/go-ethereum/crypto/sha3"
"github.com/ethereum/go-ethereum/p2p/discover"
)
@ -23,8 +24,14 @@ func startTestServer(t *testing.T, pf newPeerHook) *Server {
newPeerHook: pf,
setupFunc: func(fd net.Conn, prv *ecdsa.PrivateKey, our *protoHandshake, dial *discover.Node) (*conn, error) {
id := randomID()
rw := newRlpxFrameRW(fd, secrets{
MAC: zero16,
AES: zero16,
IngressMAC: sha3.NewKeccak256(),
EgressMAC: sha3.NewKeccak256(),
})
return &conn{
frameRW: newFrameRW(fd, msgWriteTimeout),
MsgReadWriter: rw,
protoHandshake: &protoHandshake{ID: id, Version: baseProtocolVersion},
}, nil
},
@ -143,9 +150,7 @@ func TestServerBroadcast(t *testing.T) {
// broadcast one message
srv.Broadcast("discard", 0, "foo")
goldbuf := new(bytes.Buffer)
writeMsg(goldbuf, NewMsg(16, "foo"))
golden := goldbuf.Bytes()
golden := unhex("66e94d166f0a2c3b884cfa59ca34")
// check that the message has been written everywhere
for i, conn := range conns {

27
whisper/peer.go
View File

@ -2,10 +2,10 @@ package whisper
import (
"fmt"
"io/ioutil"
"time"
"github.com/ethereum/go-ethereum/p2p"
"github.com/ethereum/go-ethereum/rlp"
"gopkg.in/fatih/set.v0"
)
@ -77,8 +77,7 @@ func (self *peer) broadcast(envelopes []*Envelope) error {
}
if i > 0 {
msg := p2p.NewMsg(envelopesMsg, envs[:i]...)
if err := self.ws.WriteMsg(msg); err != nil {
if err := p2p.EncodeMsg(self.ws, envelopesMsg, envs[:i]...); err != nil {
return err
}
self.peer.DebugDetailln("broadcasted", i, "message(s)")
@ -93,34 +92,28 @@ func (self *peer) addKnown(envelope *Envelope) {
func (self *peer) handleStatus() error {
ws := self.ws
if err := ws.WriteMsg(self.statusMsg()); err != nil {
return err
}
msg, err := ws.ReadMsg()
if err != nil {
return err
}
if msg.Code != statusMsg {
return fmt.Errorf("peer send %x before status msg", msg.Code)
}
data, err := ioutil.ReadAll(msg.Payload)
s := rlp.NewStream(msg.Payload)
if _, err := s.List(); err != nil {
return fmt.Errorf("bad status message: %v", err)
}
pv, err := s.Uint()
if err != nil {
return err
return fmt.Errorf("bad status message: %v", err)
}
if len(data) == 0 {
return fmt.Errorf("malformed status. data len = 0")
}
if pv := data[0]; pv != protocolVersion {
if pv != protocolVersion {
return fmt.Errorf("protocol version mismatch %d != %d", pv, protocolVersion)
}
return nil
return msg.Discard() // ignore anything after protocol version
}
func (self *peer) statusMsg() p2p.Msg {