eth: time out status message exchange after 5s

This commit is contained in:
Felix Lange 2015-10-22 22:22:04 +02:00
parent 77878f76a9
commit 3cf74336c9

@ -21,6 +21,7 @@ import (
"fmt"
"math/big"
"sync"
"time"
"github.com/ethereum/go-ethereum/common"
"github.com/ethereum/go-ethereum/core/types"
@ -40,6 +41,7 @@ var (
const (
maxKnownTxs = 32768 // Maximum transactions hashes to keep in the known list (prevent DOS)
maxKnownBlocks = 1024 // Maximum block hashes to keep in the known list (prevent DOS)
handshakeTimeout = 5 * time.Second
)
type peer struct {
@ -267,8 +269,8 @@ func (p *peer) RequestReceipts(hashes []common.Hash) error {
// Handshake executes the eth protocol handshake, negotiating version number,
// network IDs, difficulties, head and genesis blocks.
func (p *peer) Handshake(td *big.Int, head common.Hash, genesis common.Hash) error {
// Send out own handshake in a new thread
errc := make(chan error, 1)
errc := make(chan error, 2)
var status statusData // safe to read after two values have been received from errc
go func() {
errc <- p2p.Send(p.rw, StatusMsg, &statusData{
ProtocolVersion: uint32(p.version),
@ -278,7 +280,26 @@ func (p *peer) Handshake(td *big.Int, head common.Hash, genesis common.Hash) err
GenesisBlock: genesis,
})
}()
// In the mean time retrieve the remote status message
go func() {
errc <- p.readStatus(&status, genesis)
}()
timeout := time.NewTimer(handshakeTimeout)
defer timeout.Stop()
for i := 0; i < 2; i++ {
select {
case err := <-errc:
if err != nil {
return err
}
case <-timeout.C:
return p2p.DiscReadTimeout
}
}
p.td, p.head = status.TD, status.CurrentBlock
return nil
}
func (p *peer) readStatus(status *statusData, genesis common.Hash) (err error) {
msg, err := p.rw.ReadMsg()
if err != nil {
return err
@ -290,7 +311,6 @@ func (p *peer) Handshake(td *big.Int, head common.Hash, genesis common.Hash) err
return errResp(ErrMsgTooLarge, "%v > %v", msg.Size, ProtocolMaxMsgSize)
}
// Decode the handshake and make sure everything matches
var status statusData
if err := msg.Decode(&status); err != nil {
return errResp(ErrDecode, "msg %v: %v", msg, err)
}
@ -303,9 +323,7 @@ func (p *peer) Handshake(td *big.Int, head common.Hash, genesis common.Hash) err
if int(status.ProtocolVersion) != p.version {
return errResp(ErrProtocolVersionMismatch, "%d (!= %d)", status.ProtocolVersion, p.version)
}
// Configure the remote peer, and sanity check out handshake too
p.td, p.head = status.TD, status.CurrentBlock
return <-errc
return nil
}
// String implements fmt.Stringer.