p2p: move rlpx into separate package (#21464)

This change moves the RLPx protocol implementation into a separate package,
p2p/rlpx. The new package can be used to establish RLPx connections for
protocol testing purposes.

Co-authored-by: Felix Lange <fjl@twurst.com>

p2p/transport_test.go

@@ -0,0 +1,148 @@
+// Copyright 2015 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 p2p
+
+import (
+	"errors"
+	"reflect"
+	"sync"
+	"testing"
+
+	"github.com/davecgh/go-spew/spew"
+	"github.com/ethereum/go-ethereum/crypto"
+	"github.com/ethereum/go-ethereum/p2p/simulations/pipes"
+)
+
+func TestProtocolHandshake(t *testing.T) {
+	var (
+		prv0, _ = crypto.GenerateKey()
+		pub0    = crypto.FromECDSAPub(&prv0.PublicKey)[1:]
+		hs0     = &protoHandshake{Version: 3, ID: pub0, Caps: []Cap{{"a", 0}, {"b", 2}}}
+
+		prv1, _ = crypto.GenerateKey()
+		pub1    = crypto.FromECDSAPub(&prv1.PublicKey)[1:]
+		hs1     = &protoHandshake{Version: 3, ID: pub1, Caps: []Cap{{"c", 1}, {"d", 3}}}
+
+		wg sync.WaitGroup
+	)
+
+	fd0, fd1, err := pipes.TCPPipe()
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	wg.Add(2)
+	go func() {
+		defer wg.Done()
+		defer fd0.Close()
+		frame := newRLPX(fd0, &prv1.PublicKey)
+		rpubkey, err := frame.doEncHandshake(prv0)
+		if err != nil {
+			t.Errorf("dial side enc handshake failed: %v", err)
+			return
+		}
+		if !reflect.DeepEqual(rpubkey, &prv1.PublicKey) {
+			t.Errorf("dial side remote pubkey mismatch: got %v, want %v", rpubkey, &prv1.PublicKey)
+			return
+		}
+
+		phs, err := frame.doProtoHandshake(hs0)
+		if err != nil {
+			t.Errorf("dial side proto handshake error: %v", err)
+			return
+		}
+		phs.Rest = nil
+		if !reflect.DeepEqual(phs, hs1) {
+			t.Errorf("dial side proto handshake mismatch:\ngot: %s\nwant: %s\n", spew.Sdump(phs), spew.Sdump(hs1))
+			return
+		}
+		frame.close(DiscQuitting)
+	}()
+	go func() {
+		defer wg.Done()
+		defer fd1.Close()
+		rlpx := newRLPX(fd1, nil)
+		rpubkey, err := rlpx.doEncHandshake(prv1)
+		if err != nil {
+			t.Errorf("listen side enc handshake failed: %v", err)
+			return
+		}
+		if !reflect.DeepEqual(rpubkey, &prv0.PublicKey) {
+			t.Errorf("listen side remote pubkey mismatch: got %v, want %v", rpubkey, &prv0.PublicKey)
+			return
+		}
+
+		phs, err := rlpx.doProtoHandshake(hs1)
+		if err != nil {
+			t.Errorf("listen side proto handshake error: %v", err)
+			return
+		}
+		phs.Rest = nil
+		if !reflect.DeepEqual(phs, hs0) {
+			t.Errorf("listen side proto handshake mismatch:\ngot: %s\nwant: %s\n", spew.Sdump(phs), spew.Sdump(hs0))
+			return
+		}
+
+		if err := ExpectMsg(rlpx, discMsg, []DiscReason{DiscQuitting}); err != nil {
+			t.Errorf("error receiving disconnect: %v", err)
+		}
+	}()
+	wg.Wait()
+}
+
+func TestProtocolHandshakeErrors(t *testing.T) {
+	tests := []struct {
+		code uint64
+		msg  interface{}
+		err  error
+	}{
+		{
+			code: discMsg,
+			msg:  []DiscReason{DiscQuitting},
+			err:  DiscQuitting,
+		},
+		{
+			code: 0x989898,
+			msg:  []byte{1},
+			err:  errors.New("expected handshake, got 989898"),
+		},
+		{
+			code: handshakeMsg,
+			msg:  make([]byte, baseProtocolMaxMsgSize+2),
+			err:  errors.New("message too big"),
+		},
+		{
+			code: handshakeMsg,
+			msg:  []byte{1, 2, 3},
+			err:  newPeerError(errInvalidMsg, "(code 0) (size 4) rlp: expected input list for p2p.protoHandshake"),
+		},
+		{
+			code: handshakeMsg,
+			msg:  &protoHandshake{Version: 3},
+			err:  DiscInvalidIdentity,
+		},
+	}
+
+	for i, test := range tests {
+		p1, p2 := MsgPipe()
+		go Send(p1, test.code, test.msg)
+		_, err := readProtocolHandshake(p2)
+		if !reflect.DeepEqual(err, test.err) {
+			t.Errorf("test %d: error mismatch: got %q, want %q", i, err, test.err)
+		}
+	}
+}