p2p/rlpx: reduce allocation and syscalls (#22899)

This change significantly improves the performance of RLPx message reads
and writes. In the previous implementation, reading and writing of
message frames performed multiple reads and writes on the underlying
network connection, and allocated a new []byte buffer for every read.

In the new implementation, reads and writes re-use buffers, and perform
much fewer system calls on the underlying connection. This doubles the
theoretically achievable throughput on a single connection, as shown by
the benchmark result:

    name             old speed      new speed       delta
    Throughput-8     70.3MB/s ± 0%  155.4MB/s ± 0%  +121.11%  (p=0.000 n=9+8)

The change also removes support for the legacy, pre-EIP-8 handshake encoding.
As of May 2021, no actively maintained client sends this format.
This commit is contained in:
Felix Lange 2021-05-27 10:19:13 +02:00 committed by GitHub
parent 2e7714f864
commit 7194c847b6
No known key found for this signature in database
GPG Key ID: 4AEE18F83AFDEB23
7 changed files with 480 additions and 229 deletions

127
p2p/rlpx/buffer.go Normal file
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@ -0,0 +1,127 @@
// Copyright 2021 The go-ethereum Authors
// This file is part of the go-ethereum library.
//
// The go-ethereum library is free software: you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// The go-ethereum library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
package rlpx
import (
"io"
)
// readBuffer implements buffering for network reads. This type is similar to bufio.Reader,
// with two crucial differences: the buffer slice is exposed, and the buffer keeps all
// read data available until reset.
//
// How to use this type:
//
// Keep a readBuffer b alongside the underlying network connection. When reading a packet
// from the connection, first call b.reset(). This empties b.data. Now perform reads
// through b.read() until the end of the packet is reached. The complete packet data is
// now available in b.data.
type readBuffer struct {
data []byte
end int
}
// reset removes all processed data which was read since the last call to reset.
// After reset, len(b.data) is zero.
func (b *readBuffer) reset() {
unprocessed := b.end - len(b.data)
copy(b.data[:unprocessed], b.data[len(b.data):b.end])
b.end = unprocessed
b.data = b.data[:0]
}
// read reads at least n bytes from r, returning the bytes.
// The returned slice is valid until the next call to reset.
func (b *readBuffer) read(r io.Reader, n int) ([]byte, error) {
offset := len(b.data)
have := b.end - len(b.data)
// If n bytes are available in the buffer, there is no need to read from r at all.
if have >= n {
b.data = b.data[:offset+n]
return b.data[offset : offset+n], nil
}
// Make buffer space available.
need := n - have
b.grow(need)
// Read.
rn, err := io.ReadAtLeast(r, b.data[b.end:cap(b.data)], need)
if err != nil {
return nil, err
}
b.end += rn
b.data = b.data[:offset+n]
return b.data[offset : offset+n], nil
}
// grow ensures the buffer has at least n bytes of unused space.
func (b *readBuffer) grow(n int) {
if cap(b.data)-b.end >= n {
return
}
need := n - (cap(b.data) - b.end)
offset := len(b.data)
b.data = append(b.data[:cap(b.data)], make([]byte, need)...)
b.data = b.data[:offset]
}
// writeBuffer implements buffering for network writes. This is essentially
// a convenience wrapper around a byte slice.
type writeBuffer struct {
data []byte
}
func (b *writeBuffer) reset() {
b.data = b.data[:0]
}
func (b *writeBuffer) appendZero(n int) []byte {
offset := len(b.data)
b.data = append(b.data, make([]byte, n)...)
return b.data[offset : offset+n]
}
func (b *writeBuffer) Write(data []byte) (int, error) {
b.data = append(b.data, data...)
return len(data), nil
}
const maxUint24 = int(^uint32(0) >> 8)
func readUint24(b []byte) uint32 {
return uint32(b[2]) | uint32(b[1])<<8 | uint32(b[0])<<16
}
func putUint24(v uint32, b []byte) {
b[0] = byte(v >> 16)
b[1] = byte(v >> 8)
b[2] = byte(v)
}
// growslice ensures b has the wanted length by either expanding it to its capacity
// or allocating a new slice if b has insufficient capacity.
func growslice(b []byte, wantLength int) []byte {
if len(b) >= wantLength {
return b
}
if cap(b) >= wantLength {
return b[:cap(b)]
}
return make([]byte, wantLength)
}

51
p2p/rlpx/buffer_test.go Normal file
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@ -0,0 +1,51 @@
// Copyright 2021 The go-ethereum Authors
// This file is part of the go-ethereum library.
//
// The go-ethereum library is free software: you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// The go-ethereum library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
package rlpx
import (
"bytes"
"testing"
"github.com/ethereum/go-ethereum/common/hexutil"
"github.com/stretchr/testify/assert"
)
func TestReadBufferReset(t *testing.T) {
reader := bytes.NewReader(hexutil.MustDecode("0x010202030303040505"))
var b readBuffer
s1, _ := b.read(reader, 1)
s2, _ := b.read(reader, 2)
s3, _ := b.read(reader, 3)
assert.Equal(t, []byte{1}, s1)
assert.Equal(t, []byte{2, 2}, s2)
assert.Equal(t, []byte{3, 3, 3}, s3)
b.reset()
s4, _ := b.read(reader, 1)
s5, _ := b.read(reader, 2)
assert.Equal(t, []byte{4}, s4)
assert.Equal(t, []byte{5, 5}, s5)
s6, err := b.read(reader, 2)
assert.EqualError(t, err, "EOF")
assert.Nil(t, s6)
}

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@ -48,19 +48,45 @@ import (
// This type is not generally safe for concurrent use, but reading and writing of messages
// may happen concurrently after the handshake.
type Conn struct {
dialDest *ecdsa.PublicKey
conn net.Conn
handshake *handshakeState
snappy bool
dialDest *ecdsa.PublicKey
conn net.Conn
session *sessionState
// These are the buffers for snappy compression.
// Compression is enabled if they are non-nil.
snappyReadBuffer []byte
snappyWriteBuffer []byte
}
type handshakeState struct {
// sessionState contains the session keys.
type sessionState struct {
enc cipher.Stream
dec cipher.Stream
macCipher cipher.Block
egressMAC hash.Hash
ingressMAC hash.Hash
egressMAC hashMAC
ingressMAC hashMAC
rbuf readBuffer
wbuf writeBuffer
}
// hashMAC holds the state of the RLPx v4 MAC contraption.
type hashMAC struct {
cipher cipher.Block
hash hash.Hash
aesBuffer [16]byte
hashBuffer [32]byte
seedBuffer [32]byte
}
func newHashMAC(cipher cipher.Block, h hash.Hash) hashMAC {
m := hashMAC{cipher: cipher, hash: h}
if cipher.BlockSize() != len(m.aesBuffer) {
panic(fmt.Errorf("invalid MAC cipher block size %d", cipher.BlockSize()))
}
if h.Size() != len(m.hashBuffer) {
panic(fmt.Errorf("invalid MAC digest size %d", h.Size()))
}
return m
}
// NewConn wraps the given network connection. If dialDest is non-nil, the connection
@ -76,7 +102,13 @@ func NewConn(conn net.Conn, dialDest *ecdsa.PublicKey) *Conn {
// after the devp2p Hello message exchange when the negotiated version indicates that
// compression is available on both ends of the connection.
func (c *Conn) SetSnappy(snappy bool) {
c.snappy = snappy
if snappy {
c.snappyReadBuffer = []byte{}
c.snappyWriteBuffer = []byte{}
} else {
c.snappyReadBuffer = nil
c.snappyWriteBuffer = nil
}
}
// SetReadDeadline sets the deadline for all future read operations.
@ -95,12 +127,13 @@ func (c *Conn) SetDeadline(time time.Time) error {
}
// Read reads a message from the connection.
// The returned data buffer is valid until the next call to Read.
func (c *Conn) Read() (code uint64, data []byte, wireSize int, err error) {
if c.handshake == nil {
if c.session == nil {
panic("can't ReadMsg before handshake")
}
frame, err := c.handshake.readFrame(c.conn)
frame, err := c.session.readFrame(c.conn)
if err != nil {
return 0, nil, 0, err
}
@ -111,7 +144,7 @@ func (c *Conn) Read() (code uint64, data []byte, wireSize int, err error) {
wireSize = len(data)
// If snappy is enabled, verify and decompress message.
if c.snappy {
if c.snappyReadBuffer != nil {
var actualSize int
actualSize, err = snappy.DecodedLen(data)
if err != nil {
@ -120,51 +153,55 @@ func (c *Conn) Read() (code uint64, data []byte, wireSize int, err error) {
if actualSize > maxUint24 {
return code, nil, 0, errPlainMessageTooLarge
}
data, err = snappy.Decode(nil, data)
c.snappyReadBuffer = growslice(c.snappyReadBuffer, actualSize)
data, err = snappy.Decode(c.snappyReadBuffer, data)
}
return code, data, wireSize, err
}
func (h *handshakeState) readFrame(conn io.Reader) ([]byte, error) {
// read the header
headbuf := make([]byte, 32)
if _, err := io.ReadFull(conn, headbuf); err != nil {
func (h *sessionState) readFrame(conn io.Reader) ([]byte, error) {
h.rbuf.reset()
// Read the frame header.
header, err := h.rbuf.read(conn, 32)
if err != nil {
return nil, err
}
// verify header mac
shouldMAC := updateMAC(h.ingressMAC, h.macCipher, headbuf[:16])
if !hmac.Equal(shouldMAC, headbuf[16:]) {
// Verify header MAC.
wantHeaderMAC := h.ingressMAC.computeHeader(header[:16])
if !hmac.Equal(wantHeaderMAC, header[16:]) {
return nil, errors.New("bad header MAC")
}
h.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
// Decrypt the frame header to get the frame size.
h.dec.XORKeyStream(header[:16], header[:16])
fsize := readUint24(header[:16])
// Frame size rounded up to 16 byte boundary for padding.
rsize := fsize
if padding := fsize % 16; padding > 0 {
rsize += 16 - padding
}
framebuf := make([]byte, rsize)
if _, err := io.ReadFull(conn, framebuf); err != nil {
// Read the frame content.
frame, err := h.rbuf.read(conn, int(rsize))
if err != nil {
return nil, err
}
// read and validate frame MAC. we can re-use headbuf for that.
h.ingressMAC.Write(framebuf)
fmacseed := h.ingressMAC.Sum(nil)
if _, err := io.ReadFull(conn, headbuf[:16]); err != nil {
// Validate frame MAC.
frameMAC, err := h.rbuf.read(conn, 16)
if err != nil {
return nil, err
}
shouldMAC = updateMAC(h.ingressMAC, h.macCipher, fmacseed)
if !hmac.Equal(shouldMAC, headbuf[:16]) {
wantFrameMAC := h.ingressMAC.computeFrame(frame)
if !hmac.Equal(wantFrameMAC, frameMAC) {
return nil, errors.New("bad frame MAC")
}
// decrypt frame content
h.dec.XORKeyStream(framebuf, framebuf)
return framebuf[:fsize], nil
// Decrypt the frame data.
h.dec.XORKeyStream(frame, frame)
return frame[:fsize], nil
}
// Write writes a message to the connection.
@ -172,83 +209,90 @@ func (h *handshakeState) readFrame(conn io.Reader) ([]byte, error) {
// Write returns the written size of the message data. This may be less than or equal to
// len(data) depending on whether snappy compression is enabled.
func (c *Conn) Write(code uint64, data []byte) (uint32, error) {
if c.handshake == nil {
if c.session == nil {
panic("can't WriteMsg before handshake")
}
if len(data) > maxUint24 {
return 0, errPlainMessageTooLarge
}
if c.snappy {
data = snappy.Encode(nil, data)
if c.snappyWriteBuffer != nil {
// Ensure the buffer has sufficient size.
// Package snappy will allocate its own buffer if the provided
// one is smaller than MaxEncodedLen.
c.snappyWriteBuffer = growslice(c.snappyWriteBuffer, snappy.MaxEncodedLen(len(data)))
data = snappy.Encode(c.snappyWriteBuffer, data)
}
wireSize := uint32(len(data))
err := c.handshake.writeFrame(c.conn, code, data)
err := c.session.writeFrame(c.conn, code, data)
return wireSize, err
}
func (h *handshakeState) writeFrame(conn io.Writer, code uint64, data []byte) error {
ptype, _ := rlp.EncodeToBytes(code)
func (h *sessionState) writeFrame(conn io.Writer, code uint64, data []byte) error {
h.wbuf.reset()
// write header
headbuf := make([]byte, 32)
fsize := len(ptype) + len(data)
// Write header.
fsize := rlp.IntSize(code) + len(data)
if fsize > maxUint24 {
return errPlainMessageTooLarge
}
putInt24(uint32(fsize), headbuf)
copy(headbuf[3:], zeroHeader)
h.enc.XORKeyStream(headbuf[:16], headbuf[:16]) // first half is now encrypted
header := h.wbuf.appendZero(16)
putUint24(uint32(fsize), header)
copy(header[3:], zeroHeader)
h.enc.XORKeyStream(header, header)
// write header MAC
copy(headbuf[16:], updateMAC(h.egressMAC, h.macCipher, headbuf[:16]))
if _, err := conn.Write(headbuf); err != nil {
return err
}
// Write header MAC.
h.wbuf.Write(h.egressMAC.computeHeader(header))
// write encrypted frame, updating the egress MAC hash with
// the data written to conn.
tee := cipher.StreamWriter{S: h.enc, W: io.MultiWriter(conn, h.egressMAC)}
if _, err := tee.Write(ptype); err != nil {
return err
}
if _, err := tee.Write(data); err != nil {
return err
}
// Encode and encrypt the frame data.
offset := len(h.wbuf.data)
h.wbuf.data = rlp.AppendUint64(h.wbuf.data, code)
h.wbuf.Write(data)
if padding := fsize % 16; padding > 0 {
if _, err := tee.Write(zero16[:16-padding]); err != nil {
return err
}
h.wbuf.appendZero(16 - padding)
}
framedata := h.wbuf.data[offset:]
h.enc.XORKeyStream(framedata, framedata)
// write frame MAC. egress MAC hash is up to date because
// frame content was written to it as well.
fmacseed := h.egressMAC.Sum(nil)
mac := updateMAC(h.egressMAC, h.macCipher, fmacseed)
_, err := conn.Write(mac)
// Write frame MAC.
h.wbuf.Write(h.egressMAC.computeFrame(framedata))
_, err := conn.Write(h.wbuf.data)
return err
}
func readInt24(b []byte) uint32 {
return uint32(b[2]) | uint32(b[1])<<8 | uint32(b[0])<<16
// computeHeader computes the MAC of a frame header.
func (m *hashMAC) computeHeader(header []byte) []byte {
sum1 := m.hash.Sum(m.hashBuffer[:0])
return m.compute(sum1, header)
}
func putInt24(v uint32, b []byte) {
b[0] = byte(v >> 16)
b[1] = byte(v >> 8)
b[2] = byte(v)
// computeFrame computes the MAC of framedata.
func (m *hashMAC) computeFrame(framedata []byte) []byte {
m.hash.Write(framedata)
seed := m.hash.Sum(m.seedBuffer[:0])
return m.compute(seed, seed[:16])
}
// 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]
// compute computes the MAC of a 16-byte 'seed'.
//
// To do this, it encrypts the current value of the hash state, then XORs the ciphertext
// with seed. The obtained value is written back into the hash state and hash output is
// taken again. The first 16 bytes of the resulting sum are the MAC value.
//
// This MAC construction is a horrible, legacy thing.
func (m *hashMAC) compute(sum1, seed []byte) []byte {
if len(seed) != len(m.aesBuffer) {
panic("invalid MAC seed")
}
mac.Write(aesbuf)
return mac.Sum(nil)[:16]
m.cipher.Encrypt(m.aesBuffer[:], sum1)
for i := range m.aesBuffer {
m.aesBuffer[i] ^= seed[i]
}
m.hash.Write(m.aesBuffer[:])
sum2 := m.hash.Sum(m.hashBuffer[:0])
return sum2[:16]
}
// Handshake performs the handshake. This must be called before any data is written
@ -257,23 +301,26 @@ func (c *Conn) Handshake(prv *ecdsa.PrivateKey) (*ecdsa.PublicKey, error) {
var (
sec Secrets
err error
h handshakeState
)
if c.dialDest != nil {
sec, err = initiatorEncHandshake(c.conn, prv, c.dialDest)
sec, err = h.runInitiator(c.conn, prv, c.dialDest)
} else {
sec, err = receiverEncHandshake(c.conn, prv)
sec, err = h.runRecipient(c.conn, prv)
}
if err != nil {
return nil, err
}
c.InitWithSecrets(sec)
c.session.rbuf = h.rbuf
c.session.wbuf = h.wbuf
return sec.remote, err
}
// InitWithSecrets injects connection secrets as if a handshake had
// been performed. This cannot be called after the handshake.
func (c *Conn) InitWithSecrets(sec Secrets) {
if c.handshake != nil {
if c.session != nil {
panic("can't handshake twice")
}
macc, err := aes.NewCipher(sec.MAC)
@ -287,12 +334,11 @@ func (c *Conn) InitWithSecrets(sec Secrets) {
// we use an all-zeroes IV for AES because the key used
// for encryption is ephemeral.
iv := make([]byte, encc.BlockSize())
c.handshake = &handshakeState{
c.session = &sessionState{
enc: cipher.NewCTR(encc, iv),
dec: cipher.NewCTR(encc, iv),
macCipher: macc,
egressMAC: sec.EgressMAC,
ingressMAC: sec.IngressMAC,
egressMAC: newHashMAC(macc, sec.EgressMAC),
ingressMAC: newHashMAC(macc, sec.IngressMAC),
}
}
@ -303,28 +349,18 @@ func (c *Conn) Close() error {
// Constants for the handshake.
const (
maxUint24 = int(^uint32(0) >> 8)
sskLen = 16 // ecies.MaxSharedKeyLength(pubKey) / 2
sigLen = crypto.SignatureLength // elliptic S256
pubLen = 64 // 512 bit pubkey in uncompressed representation without format byte
shaLen = 32 // hash length (for nonce etc)
authMsgLen = sigLen + shaLen + pubLen + shaLen + 1
authRespLen = pubLen + shaLen + 1
eciesOverhead = 65 /* pubkey */ + 16 /* IV */ + 32 /* MAC */
encAuthMsgLen = authMsgLen + eciesOverhead // size of encrypted pre-EIP-8 initiator handshake
encAuthRespLen = authRespLen + eciesOverhead // size of encrypted pre-EIP-8 handshake reply
)
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)
// errPlainMessageTooLarge is returned if a decompressed message length exceeds
// the allowed 24 bits (i.e. length >= 16MB).
@ -338,19 +374,20 @@ type Secrets struct {
remote *ecdsa.PublicKey
}
// encHandshake contains the state of the encryption handshake.
type encHandshake struct {
// handshakeState contains the state of the encryption handshake.
type handshakeState struct {
initiator bool
remote *ecies.PublicKey // remote-pubk
initNonce, respNonce []byte // nonce
randomPrivKey *ecies.PrivateKey // ecdhe-random
remoteRandomPub *ecies.PublicKey // ecdhe-random-pubk
rbuf readBuffer
wbuf writeBuffer
}
// RLPx v4 handshake auth (defined in EIP-8).
type authMsgV4 struct {
gotPlain bool // whether read packet had plain format.
Signature [sigLen]byte
InitiatorPubkey [pubLen]byte
Nonce [shaLen]byte
@ -370,17 +407,16 @@ type authRespV4 struct {
Rest []rlp.RawValue `rlp:"tail"`
}
// receiverEncHandshake negotiates a session token on conn.
// runRecipient negotiates a session token on conn.
// it should be called on the listening side of the connection.
//
// prv is the local client's private key.
func receiverEncHandshake(conn io.ReadWriter, prv *ecdsa.PrivateKey) (s Secrets, err error) {
func (h *handshakeState) runRecipient(conn io.ReadWriter, prv *ecdsa.PrivateKey) (s Secrets, err error) {
authMsg := new(authMsgV4)
authPacket, err := readHandshakeMsg(authMsg, encAuthMsgLen, prv, conn)
authPacket, err := h.readMsg(authMsg, prv, conn)
if err != nil {
return s, err
}
h := new(encHandshake)
if err := h.handleAuthMsg(authMsg, prv); err != nil {
return s, err
}
@ -389,22 +425,18 @@ func receiverEncHandshake(conn io.ReadWriter, prv *ecdsa.PrivateKey) (s Secrets,
if err != nil {
return s, err
}
var authRespPacket []byte
if authMsg.gotPlain {
authRespPacket, err = authRespMsg.sealPlain(h)
} else {
authRespPacket, err = sealEIP8(authRespMsg, h)
}
authRespPacket, err := h.sealEIP8(authRespMsg)
if err != nil {
return s, err
}
if _, err = conn.Write(authRespPacket); err != nil {
return s, err
}
return h.secrets(authPacket, authRespPacket)
}
func (h *encHandshake) handleAuthMsg(msg *authMsgV4, prv *ecdsa.PrivateKey) error {
func (h *handshakeState) handleAuthMsg(msg *authMsgV4, prv *ecdsa.PrivateKey) error {
// Import the remote identity.
rpub, err := importPublicKey(msg.InitiatorPubkey[:])
if err != nil {
@ -438,7 +470,7 @@ func (h *encHandshake) handleAuthMsg(msg *authMsgV4, prv *ecdsa.PrivateKey) erro
// 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) {
func (h *handshakeState) secrets(auth, authResp []byte) (Secrets, error) {
ecdheSecret, err := h.randomPrivKey.GenerateShared(h.remoteRandomPub, sskLen, sskLen)
if err != nil {
return Secrets{}, err
@ -471,21 +503,23 @@ func (h *encHandshake) secrets(auth, authResp []byte) (Secrets, error) {
// staticSharedSecret returns the static shared secret, the result
// of key agreement between the local and remote static node key.
func (h *encHandshake) staticSharedSecret(prv *ecdsa.PrivateKey) ([]byte, error) {
func (h *handshakeState) staticSharedSecret(prv *ecdsa.PrivateKey) ([]byte, error) {
return ecies.ImportECDSA(prv).GenerateShared(h.remote, sskLen, sskLen)
}
// initiatorEncHandshake negotiates a session token on conn.
// runInitiator negotiates a session token on conn.
// it should be called on the dialing side of the connection.
//
// prv is the local client's private key.
func initiatorEncHandshake(conn io.ReadWriter, prv *ecdsa.PrivateKey, remote *ecdsa.PublicKey) (s Secrets, err error) {
h := &encHandshake{initiator: true, remote: ecies.ImportECDSAPublic(remote)}
func (h *handshakeState) runInitiator(conn io.ReadWriter, prv *ecdsa.PrivateKey, remote *ecdsa.PublicKey) (s Secrets, err error) {
h.initiator = true
h.remote = ecies.ImportECDSAPublic(remote)
authMsg, err := h.makeAuthMsg(prv)
if err != nil {
return s, err
}
authPacket, err := sealEIP8(authMsg, h)
authPacket, err := h.sealEIP8(authMsg)
if err != nil {
return s, err
}
@ -495,18 +529,19 @@ func initiatorEncHandshake(conn io.ReadWriter, prv *ecdsa.PrivateKey, remote *ec
}
authRespMsg := new(authRespV4)
authRespPacket, err := readHandshakeMsg(authRespMsg, encAuthRespLen, prv, conn)
authRespPacket, err := h.readMsg(authRespMsg, prv, conn)
if err != nil {
return s, err
}
if err := h.handleAuthResp(authRespMsg); err != nil {
return s, err
}
return h.secrets(authPacket, authRespPacket)
}
// makeAuthMsg creates the initiator handshake message.
func (h *encHandshake) makeAuthMsg(prv *ecdsa.PrivateKey) (*authMsgV4, error) {
func (h *handshakeState) makeAuthMsg(prv *ecdsa.PrivateKey) (*authMsgV4, error) {
// Generate random initiator nonce.
h.initNonce = make([]byte, shaLen)
_, err := rand.Read(h.initNonce)
@ -538,13 +573,13 @@ func (h *encHandshake) makeAuthMsg(prv *ecdsa.PrivateKey) (*authMsgV4, error) {
return msg, nil
}
func (h *encHandshake) handleAuthResp(msg *authRespV4) (err error) {
func (h *handshakeState) handleAuthResp(msg *authRespV4) (err error) {
h.respNonce = msg.Nonce[:]
h.remoteRandomPub, err = importPublicKey(msg.RandomPubkey[:])
return err
}
func (h *encHandshake) makeAuthResp() (msg *authRespV4, err error) {
func (h *handshakeState) makeAuthResp() (msg *authRespV4, err error) {
// Generate random nonce.
h.respNonce = make([]byte, shaLen)
if _, err = rand.Read(h.respNonce); err != nil {
@ -558,79 +593,51 @@ func (h *encHandshake) makeAuthResp() (msg *authRespV4, err error) {
return msg, nil
}
func (msg *authMsgV4) decodePlain(input []byte) {
n := copy(msg.Signature[:], input)
n += shaLen // skip sha3(initiator-ephemeral-pubk)
n += copy(msg.InitiatorPubkey[:], input[n:])
copy(msg.Nonce[:], input[n:])
msg.Version = 4
msg.gotPlain = true
}
// readMsg reads an encrypted handshake message, decoding it into msg.
func (h *handshakeState) readMsg(msg interface{}, prv *ecdsa.PrivateKey, r io.Reader) ([]byte, error) {
h.rbuf.reset()
h.rbuf.grow(512)
func (msg *authRespV4) sealPlain(hs *encHandshake) ([]byte, error) {
buf := make([]byte, authRespLen)
n := copy(buf, msg.RandomPubkey[:])
copy(buf[n:], msg.Nonce[:])
return ecies.Encrypt(rand.Reader, hs.remote, buf, nil, nil)
}
func (msg *authRespV4) decodePlain(input []byte) {
n := copy(msg.RandomPubkey[:], input)
copy(msg.Nonce[:], input[n:])
msg.Version = 4
}
var padSpace = make([]byte, 300)
func sealEIP8(msg interface{}, h *encHandshake) ([]byte, error) {
buf := new(bytes.Buffer)
if err := rlp.Encode(buf, msg); err != nil {
// Read the size prefix.
prefix, err := h.rbuf.read(r, 2)
if err != nil {
return nil, err
}
// pad with random amount of data. the amount needs to be at least 100 bytes to make
// the message distinguishable from pre-EIP-8 handshakes.
pad := padSpace[:mrand.Intn(len(padSpace)-100)+100]
buf.Write(pad)
prefix := make([]byte, 2)
binary.BigEndian.PutUint16(prefix, uint16(buf.Len()+eciesOverhead))
enc, err := ecies.Encrypt(rand.Reader, h.remote, buf.Bytes(), nil, prefix)
return append(prefix, enc...), err
}
type plainDecoder interface {
decodePlain([]byte)
}
func readHandshakeMsg(msg plainDecoder, plainSize int, prv *ecdsa.PrivateKey, r io.Reader) ([]byte, error) {
buf := make([]byte, plainSize)
if _, err := io.ReadFull(r, buf); err != nil {
return buf, err
}
// Attempt decoding pre-EIP-8 "plain" format.
key := ecies.ImportECDSA(prv)
if dec, err := key.Decrypt(buf, nil, nil); err == nil {
msg.decodePlain(dec)
return buf, nil
}
// Could be EIP-8 format, try that.
prefix := buf[:2]
size := binary.BigEndian.Uint16(prefix)
if size < uint16(plainSize) {
return buf, fmt.Errorf("size underflow, need at least %d bytes", plainSize)
}
buf = append(buf, make([]byte, size-uint16(plainSize)+2)...)
if _, err := io.ReadFull(r, buf[plainSize:]); err != nil {
return buf, err
}
dec, err := key.Decrypt(buf[2:], nil, prefix)
// Read the handshake packet.
packet, err := h.rbuf.read(r, int(size))
if err != nil {
return buf, err
return nil, err
}
dec, err := ecies.ImportECDSA(prv).Decrypt(packet, nil, prefix)
if err != nil {
return nil, err
}
// Can't use rlp.DecodeBytes here because it rejects
// trailing data (forward-compatibility).
s := rlp.NewStream(bytes.NewReader(dec), 0)
return buf, s.Decode(msg)
err = s.Decode(msg)
return h.rbuf.data[:len(prefix)+len(packet)], err
}
// sealEIP8 encrypts a handshake message.
func (h *handshakeState) sealEIP8(msg interface{}) ([]byte, error) {
h.wbuf.reset()
// Write the message plaintext.
if err := rlp.Encode(&h.wbuf, msg); err != nil {
return nil, err
}
// Pad with random amount of data. the amount needs to be at least 100 bytes to make
// the message distinguishable from pre-EIP-8 handshakes.
h.wbuf.appendZero(mrand.Intn(100) + 100)
prefix := make([]byte, 2)
binary.BigEndian.PutUint16(prefix, uint16(len(h.wbuf.data)+eciesOverhead))
enc, err := ecies.Encrypt(rand.Reader, h.remote, h.wbuf.data, nil, prefix)
return append(prefix, enc...), err
}
// importPublicKey unmarshals 512 bit public keys.

View File

@ -22,6 +22,7 @@ import (
"encoding/hex"
"fmt"
"io"
"math/rand"
"net"
"reflect"
"strings"
@ -30,6 +31,7 @@ import (
"github.com/davecgh/go-spew/spew"
"github.com/ethereum/go-ethereum/crypto"
"github.com/ethereum/go-ethereum/crypto/ecies"
"github.com/ethereum/go-ethereum/p2p/simulations/pipes"
"github.com/ethereum/go-ethereum/rlp"
"github.com/stretchr/testify/assert"
)
@ -124,7 +126,7 @@ func TestFrameReadWrite(t *testing.T) {
IngressMAC: hash,
EgressMAC: hash,
})
h := conn.handshake
h := conn.session
golden := unhex(`
00828ddae471818bb0bfa6b551d1cb42
@ -166,27 +168,11 @@ func (h fakeHash) Sum(b []byte) []byte { return append(b, h...) }
type handshakeAuthTest struct {
input string
isPlain bool
wantVersion uint
wantRest []rlp.RawValue
}
var eip8HandshakeAuthTests = []handshakeAuthTest{
// (Auth₁) RLPx v4 plain encoding
{
input: `
048ca79ad18e4b0659fab4853fe5bc58eb83992980f4c9cc147d2aa31532efd29a3d3dc6a3d89eaf
913150cfc777ce0ce4af2758bf4810235f6e6ceccfee1acc6b22c005e9e3a49d6448610a58e98744
ba3ac0399e82692d67c1f58849050b3024e21a52c9d3b01d871ff5f210817912773e610443a9ef14
2e91cdba0bd77b5fdf0769b05671fc35f83d83e4d3b0b000c6b2a1b1bba89e0fc51bf4e460df3105
c444f14be226458940d6061c296350937ffd5e3acaceeaaefd3c6f74be8e23e0f45163cc7ebd7622
0f0128410fd05250273156d548a414444ae2f7dea4dfca2d43c057adb701a715bf59f6fb66b2d1d2
0f2c703f851cbf5ac47396d9ca65b6260bd141ac4d53e2de585a73d1750780db4c9ee4cd4d225173
a4592ee77e2bd94d0be3691f3b406f9bba9b591fc63facc016bfa8
`,
isPlain: true,
wantVersion: 4,
},
// (Auth₂) EIP-8 encoding
{
input: `
@ -233,18 +219,6 @@ type handshakeAckTest struct {
}
var eip8HandshakeRespTests = []handshakeAckTest{
// (Ack₁) RLPx v4 plain encoding
{
input: `
049f8abcfa9c0dc65b982e98af921bc0ba6e4243169348a236abe9df5f93aa69d99cadddaa387662
b0ff2c08e9006d5a11a278b1b3331e5aaabf0a32f01281b6f4ede0e09a2d5f585b26513cb794d963
5a57563921c04a9090b4f14ee42be1a5461049af4ea7a7f49bf4c97a352d39c8d02ee4acc416388c
1c66cec761d2bc1c72da6ba143477f049c9d2dde846c252c111b904f630ac98e51609b3b1f58168d
dca6505b7196532e5f85b259a20c45e1979491683fee108e9660edbf38f3add489ae73e3dda2c71b
d1497113d5c755e942d1
`,
wantVersion: 4,
},
// (Ack₂) EIP-8 encoding
{
input: `
@ -287,10 +261,13 @@ var eip8HandshakeRespTests = []handshakeAckTest{
},
}
var (
keyA, _ = crypto.HexToECDSA("49a7b37aa6f6645917e7b807e9d1c00d4fa71f18343b0d4122a4d2df64dd6fee")
keyB, _ = crypto.HexToECDSA("b71c71a67e1177ad4e901695e1b4b9ee17ae16c6668d313eac2f96dbcda3f291")
)
func TestHandshakeForwardCompatibility(t *testing.T) {
var (
keyA, _ = crypto.HexToECDSA("49a7b37aa6f6645917e7b807e9d1c00d4fa71f18343b0d4122a4d2df64dd6fee")
keyB, _ = crypto.HexToECDSA("b71c71a67e1177ad4e901695e1b4b9ee17ae16c6668d313eac2f96dbcda3f291")
pubA = crypto.FromECDSAPub(&keyA.PublicKey)[1:]
pubB = crypto.FromECDSAPub(&keyB.PublicKey)[1:]
ephA, _ = crypto.HexToECDSA("869d6ecf5211f1cc60418a13b9d870b22959d0c16f02bec714c960dd2298a32d")
@ -304,7 +281,7 @@ func TestHandshakeForwardCompatibility(t *testing.T) {
_ = authSignature
)
makeAuth := func(test handshakeAuthTest) *authMsgV4 {
msg := &authMsgV4{Version: test.wantVersion, Rest: test.wantRest, gotPlain: test.isPlain}
msg := &authMsgV4{Version: test.wantVersion, Rest: test.wantRest}
copy(msg.Signature[:], authSignature)
copy(msg.InitiatorPubkey[:], pubA)
copy(msg.Nonce[:], nonceA)
@ -319,9 +296,10 @@ func TestHandshakeForwardCompatibility(t *testing.T) {
// check auth msg parsing
for _, test := range eip8HandshakeAuthTests {
var h handshakeState
r := bytes.NewReader(unhex(test.input))
msg := new(authMsgV4)
ciphertext, err := readHandshakeMsg(msg, encAuthMsgLen, keyB, r)
ciphertext, err := h.readMsg(msg, keyB, r)
if err != nil {
t.Errorf("error for input %x:\n %v", unhex(test.input), err)
continue
@ -337,10 +315,11 @@ func TestHandshakeForwardCompatibility(t *testing.T) {
// check auth resp parsing
for _, test := range eip8HandshakeRespTests {
var h handshakeState
input := unhex(test.input)
r := bytes.NewReader(input)
msg := new(authRespV4)
ciphertext, err := readHandshakeMsg(msg, encAuthRespLen, keyA, r)
ciphertext, err := h.readMsg(msg, keyA, r)
if err != nil {
t.Errorf("error for input %x:\n %v", input, err)
continue
@ -356,14 +335,14 @@ func TestHandshakeForwardCompatibility(t *testing.T) {
// check derivation for (Auth₂, Ack₂) on recipient side
var (
hs = &encHandshake{
hs = &handshakeState{
initiator: false,
respNonce: nonceB,
randomPrivKey: ecies.ImportECDSA(ephB),
}
authCiphertext = unhex(eip8HandshakeAuthTests[1].input)
authRespCiphertext = unhex(eip8HandshakeRespTests[1].input)
authMsg = makeAuth(eip8HandshakeAuthTests[1])
authCiphertext = unhex(eip8HandshakeAuthTests[0].input)
authRespCiphertext = unhex(eip8HandshakeRespTests[0].input)
authMsg = makeAuth(eip8HandshakeAuthTests[0])
wantAES = unhex("80e8632c05fed6fc2a13b0f8d31a3cf645366239170ea067065aba8e28bac487")
wantMAC = unhex("2ea74ec5dae199227dff1af715362700e989d889d7a493cb0639691efb8e5f98")
wantFooIngressHash = unhex("0c7ec6340062cc46f5e9f1e3cf86f8c8c403c5a0964f5df0ebd34a75ddc86db5")
@ -388,6 +367,74 @@ func TestHandshakeForwardCompatibility(t *testing.T) {
}
}
func BenchmarkHandshakeRead(b *testing.B) {
var input = unhex(eip8HandshakeAuthTests[0].input)
for i := 0; i < b.N; i++ {
var (
h handshakeState
r = bytes.NewReader(input)
msg = new(authMsgV4)
)
if _, err := h.readMsg(msg, keyB, r); err != nil {
b.Fatal(err)
}
}
}
func BenchmarkThroughput(b *testing.B) {
pipe1, pipe2, err := pipes.TCPPipe()
if err != nil {
b.Fatal(err)
}
var (
conn1, conn2 = NewConn(pipe1, nil), NewConn(pipe2, &keyA.PublicKey)
handshakeDone = make(chan error, 1)
msgdata = make([]byte, 1024)
rand = rand.New(rand.NewSource(1337))
)
rand.Read(msgdata)
// Server side.
go func() {
defer conn1.Close()
// Perform handshake.
_, err := conn1.Handshake(keyA)
handshakeDone <- err
if err != nil {
return
}
conn1.SetSnappy(true)
// Keep sending messages until connection closed.
for {
if _, err := conn1.Write(0, msgdata); err != nil {
return
}
}
}()
// Set up client side.
defer conn2.Close()
if _, err := conn2.Handshake(keyB); err != nil {
b.Fatal("client handshake error:", err)
}
conn2.SetSnappy(true)
if err := <-handshakeDone; err != nil {
b.Fatal("server hanshake error:", err)
}
// Read N messages.
b.SetBytes(int64(len(msgdata)))
b.ReportAllocs()
for i := 0; i < b.N; i++ {
_, _, _, err := conn2.Read()
if err != nil {
b.Fatal("read error:", err)
}
}
}
func unhex(str string) []byte {
r := strings.NewReplacer("\t", "", " ", "", "\n", "")
b, err := hex.DecodeString(r.Replace(str))

View File

@ -25,6 +25,7 @@ import (
"sync"
"time"
"github.com/ethereum/go-ethereum/common"
"github.com/ethereum/go-ethereum/common/bitutil"
"github.com/ethereum/go-ethereum/metrics"
"github.com/ethereum/go-ethereum/p2p/rlpx"
@ -62,6 +63,10 @@ func (t *rlpxTransport) ReadMsg() (Msg, error) {
t.conn.SetReadDeadline(time.Now().Add(frameReadTimeout))
code, data, wireSize, err := t.conn.Read()
if err == nil {
// Protocol messages are dispatched to subprotocol handlers asynchronously,
// but package rlpx may reuse the returned 'data' buffer on the next call
// to Read. Copy the message data to avoid this being an issue.
data = common.CopyBytes(data)
msg = Msg{
ReceivedAt: time.Now(),
Code: code,

View File

@ -34,6 +34,14 @@ func ListSize(contentSize uint64) uint64 {
return uint64(headsize(contentSize)) + contentSize
}
// IntSize returns the encoded size of the integer x.
func IntSize(x uint64) int {
if x < 0x80 {
return 1
}
return 1 + intsize(x)
}
// Split returns the content of first RLP value and any
// bytes after the value as subslices of b.
func Split(b []byte) (k Kind, content, rest []byte, err error) {

View File

@ -263,6 +263,12 @@ func TestAppendUint64(t *testing.T) {
if !bytes.Equal(x, unhex(test.output)) {
t.Errorf("AppendUint64(%v, %d): got %x, want %s", test.slice, test.input, x, test.output)
}
// Check that IntSize returns the appended size.
length := len(x) - len(test.slice)
if s := IntSize(test.input); s != length {
t.Errorf("IntSize(%d): got %d, want %d", test.input, s, length)
}
}
}