// GetData retrieves requests objects with the specified hashes from the
// peer node that sent us ver. It returns the number of objects
// successfully received and an error if n < len(hashes).
func (nd *Node) GetData(ver *payload.Version, hashes [][]byte) (n int, err error) {
conn, err := net.DialTimeout("tcp", ver.FromAddr.Addr(), defaultTimeout)
if err != nil {
return n, err
}
defer conn.Close()
pay, err := payload.GetDataEncode(ver.Protocol(), hashes)
if err != nil {
panic(err)
}
m := msg.New(msg.Cgetdata, pay)
conn.Write(m.Encode())
for i := 0; i < len(hashes); i++ {
m, err := msg.Decode(conn)
if err != nil {
return n, err
}
switch m.Cmd() {
case msg.Cversion, msg.Cverack, msg.Caddr, msg.Cinv, msg.Cgetdata:
return n, fmt.Errorf("getdata resp contains invalid msg type %v", m.Cmd())
}
nd.ObjectsIn <- m
n++
}
return n, nil
}
func (n *Node) sendInvAndAddr(conn net.Conn, proto uint32) {
pay, err := payload.AddrEncode(proto, n.MyPeers...)
if err != nil {
panic(err)
}
am := msg.New(msg.Caddr, pay)
if _, err := conn.Write(am.Encode()); err != nil {
panic(err)
}
pay, err = payload.InventoryEncode(proto, n.invList())
if err != nil {
panic(err)
}
im := msg.New(msg.Cinv, pay)
if _, err := conn.Write(im.Encode()); err != nil {
panic(err)
}
}
func (n *Node) verOutVerackIn(conn net.Conn, to *payload.AddressInfo, proto uint32) {
vcopy := *n.MyVer
vcopy.Timestamp = time.Now()
vcopy.ToAddr = to
pay, err := vcopy.Encode(proto)
if err != nil {
panic(err)
}
m := msg.New(msg.Cversion, pay)
if _, err := conn.Write(m.Encode()); err != nil {
panic(err)
}
msg.Must(msg.ReadKind(conn, msg.Cverack))
}
func (n *Node) versionExchange(addr *payload.AddressInfo) {
resp := &VerDat{}
defer func() { n.VerIn <- resp }()
defer func() {
if r := recover(); r != nil {
resp.Err = fmt.Errorf("[ERR] version exchange did not complete (%v)", r)
n.Log.Print(resp.Err)
}
}()
n.Log.Printf("[INFO] version exchange with %v", addr.Addr())
conn, err := net.DialTimeout("tcp", addr.Addr(), defaultTimeout)
if err != nil {
panic(err)
}
defer conn.Close()
n.verOutVerackIn(conn, addr, payload.ProtocolVersion)
// wait for version message and send verack
m := msg.Must(msg.ReadKind(conn, msg.Cversion))
resp.Ver, err = payload.VersionDecode(m.Payload())
if err != nil {
panic(err)
}
if _, err := conn.Write(msg.New(msg.Cverack, []byte{}).Encode()); err != nil {
panic(err)
}
n.sendInvAndAddr(conn, resp.Ver.Protocol())
// wait for addr and inv messages
m = msg.Must(msg.ReadKind(conn, msg.Caddr))
resp.Peers, err = payload.AddrDecode(resp.Ver.Protocol(), m.Payload())
if err != nil {
panic(err)
}
m = msg.Must(msg.ReadKind(conn, msg.Cinv))
resp.Inv, err = payload.InventoryDecode(resp.Ver.Protocol(), m.Payload())
if err != nil {
panic(err)
}
n.Log.Printf("[INFO] version exchange with %v successful", addr.Addr())
}
func (n *Node) versionSequence(m *msg.Msg, conn net.Conn) {
resp := &VerDat{}
defer func() {
if r := recover(); r != nil {
resp.Err = fmt.Errorf("[ERR] version sequence did not complete (%v)", r)
n.Log.Print(resp.Err)
}
}()
var err error
n.Log.Printf("[INFO] version sequence with %v", conn.RemoteAddr())
resp.Ver, err = payload.VersionDecode(m.Payload())
if err != nil {
panic(err)
}
defer func() { n.VerIn <- resp }()
if _, err := conn.Write(msg.New(msg.Cverack, []byte{}).Encode()); err != nil {
panic(err)
}
n.verOutVerackIn(conn, resp.Ver.FromAddr, resp.Ver.Protocol())
n.sendInvAndAddr(conn, resp.Ver.Protocol())
// wait for addr and inv messages
m = msg.Must(msg.ReadKind(conn, msg.Caddr))
resp.Peers, err = payload.AddrDecode(resp.Ver.Protocol(), m.Payload())
if err != nil {
panic(err)
}
m = msg.Must(msg.ReadKind(conn, msg.Cinv))
resp.Inv, err = payload.InventoryDecode(resp.Ver.Protocol(), m.Payload())
if err != nil {
panic(err)
}
n.Log.Printf("[INFO] version sequence with %v successful", conn.RemoteAddr())
}