// Announce announces using UDP format
func (u UDPTracker) Announce(query url.Values, file data.FileRecord) []byte {
// Create UDP announce response
announce := udp.AnnounceResponse{
Action: 1,
TransID: u.TransID,
Interval: uint32(common.Static.Config.Interval),
Leechers: uint32(file.Leechers()),
Seeders: uint32(file.Seeders()),
}
// Convert to UDP byte buffer
announceBuf, err := announce.MarshalBinary()
if err != nil {
log.Println(err.Error())
return u.Error("Could not create UDP announce response")
}
// Numwant
numwant, err := strconv.Atoi(query.Get("numwant"))
if err != nil {
numwant = 50
}
// Add compact peer list
res := bytes.NewBuffer(announceBuf)
err = binary.Write(res, binary.BigEndian, file.PeerList(query.Get("ip"), numwant))
if err != nil {
log.Println(err.Error())
return u.Error("Could not create UDP announce response")
}
return res.Bytes()
}
// TestUDPAnnounce verifies that the UDP tracker announce output format is correct
func TestUDPAnnounce(t *testing.T) {
log.Println("TestUDPAnnounce()")
// Load config
config := common.LoadConfig()
common.Static.Config = config
// Generate mock data.FileRecord
file := data.FileRecord{
InfoHash: "6465616462656566",
Verified: true,
}
// Save mock file
if !file.Save() {
t.Fatalf("Failed to save mock file")
}
// Generate fake announce query
query := url.Values{}
query.Set("info_hash", "deadbeef")
query.Set("ip", "127.0.0.1")
query.Set("port", "5000")
query.Set("uploaded", "0")
query.Set("downloaded", "0")
query.Set("left", "0")
query.Set("numwant", "50")
// Create a UDP tracker, trigger an announce
tracker := UDPTracker{TransID: uint32(1234)}
res := tracker.Announce(query, file)
// Decode response
announce := new(udp.AnnounceResponse)
err := announce.UnmarshalBinary(res)
if err != nil {
t.Fatalf("Failed to decode UDP announce response")
}
log.Println(announce)
// Verify correct action
if announce.Action != 1 {
t.Fatalf("Incorrect UDP action, expected 1")
}
// Encode response, verify same as before
announceBuf, err := announce.MarshalBinary()
if err != nil {
t.Fatalf("Failed to encode UDP announce response")
}
if !bytes.Equal(res, announceBuf) {
t.Fatalf("Byte slices are not identical")
}
// Delete mock file
if !file.Delete() {
t.Fatalf("Failed to delete mock file")
}
}
// Announce announces using UDP format
func (u UDPTracker) Announce(query url.Values, file data.FileRecord) []byte {
// Create UDP announce response
announce := udp.AnnounceResponse{
Action: 1,
TransID: u.TransID,
Interval: uint32(common.Static.Config.Interval),
}
// Calculate file seeders and leechers
seeders, err := file.Seeders()
if err != nil {
log.Println(err.Error())
}
announce.Seeders = uint32(seeders)
leechers, err := file.Leechers()
if err != nil {
log.Println(err.Error())
}
announce.Leechers = uint32(leechers)
// Convert to UDP byte buffer
announceBuf, err := announce.MarshalBinary()
if err != nil {
log.Println(err.Error())
return u.Error(ErrAnnounceFailure.Error())
}
// Numwant
numwant, err := strconv.Atoi(query.Get("numwant"))
if err != nil {
numwant = 50
}
// Retrieve compact peer list
// Note: because we are UDP, we send the second parameter 'false' to get
// a "best guess" peer list, due to anonymous announces
peers, err := file.CompactPeerList(numwant, false)
if err != nil {
log.Println(err.Error())
return u.Error(ErrPeerListFailure.Error())
}
// Add compact peer list
res := bytes.NewBuffer(announceBuf)
err = binary.Write(res, binary.BigEndian, peers)
if err != nil {
log.Println(err.Error())
return u.Error(ErrPeerListFailure.Error())
}
return res.Bytes()
}
// TestUDPRouter verifies that the main UDP router is working properly
func TestUDPRouter(t *testing.T) {
log.Println("TestUDPRouter()")
// Load config
config, err := common.LoadConfig()
if err != nil {
t.Fatalf("Could not load configuration: %s", err.Error())
}
common.Static.Config = config
// Generate mock data.FileRecord
file := data.FileRecord{
InfoHash: "6465616462656566303030303030303030303030",
Verified: true,
}
// Save mock file
if err := file.Save(); err != nil {
t.Fatalf("Failed to save mock file: %s", err.Error())
}
// Fake UDP address
addr, err := net.ResolveUDPAddr("udp", "127.0.0.1:0")
if err != nil {
t.Fatalf("Failed to create fake UDP address")
}
// Connect packet with handshake
connect := udp.Packet{udpInitID, 0, 1234}
connectBuf, err := connect.MarshalBinary()
if err != nil {
t.Fatalf("Failed to create UDP connect packet")
}
// Perform connection handshake
res, err := parseUDP(connectBuf, addr)
if err != nil {
errRes := new(udp.ErrorResponse)
err2 := errRes.UnmarshalBinary(res)
if err2 != nil {
t.Fatalf(err.Error())
}
log.Println("ERROR:", errRes.Error)
t.Fatalf(err.Error())
}
// Retrieve response, get new connection ID, which will be expected by router
connRes := new(udp.ConnectResponse)
err = connRes.UnmarshalBinary(res)
if err != nil {
t.Fatalf(err.Error())
}
// Create announce request
announce := udp.AnnounceRequest{
ConnID: connRes.ConnID,
Action: 1,
TransID: connRes.TransID,
InfoHash: []byte("deadbeef000000000000"),
PeerID: []byte("00001111222233334444"),
Downloaded: 0,
Left: 0,
Uploaded: 0,
IP: 0,
Key: 1234,
Port: 5000,
}
// Get announce bytes
announceBuf, err := announce.MarshalBinary()
if err != nil {
t.Fatalf(err.Error())
}
// Send announce to UDP router
res, err = parseUDP(announceBuf, addr)
if err != nil {
errRes := new(udp.ErrorResponse)
err2 := errRes.UnmarshalBinary(res)
if err2 != nil {
t.Fatalf(err.Error())
}
log.Println("ERROR:", errRes.Error)
t.Fatalf(err.Error())
}
// Get UDP announce response
announceRes := new(udp.AnnounceResponse)
err = announceRes.UnmarshalBinary(res)
if err != nil {
errRes := new(udp.ErrorResponse)
err2 := errRes.UnmarshalBinary(res)
if err2 != nil {
t.Fatalf(err.Error())
}
log.Println("ERROR:", errRes.Error)
t.Fatalf(err.Error())
}
log.Println(announceRes)
// Create scrape request
scrape := udp.ScrapeRequest{
ConnID: connRes.ConnID,
Action: 2,
TransID: connRes.TransID,
InfoHashes: [][]byte{[]byte("deadbeef000000000000")},
}
// Get scrape bytes
scrapeBuf, err := scrape.MarshalBinary()
if err != nil {
t.Fatalf(err.Error())
}
// Send scrape to UDP router
res, err = parseUDP(scrapeBuf, addr)
if err != nil {
errRes := new(udp.ErrorResponse)
err2 := errRes.UnmarshalBinary(res)
if err2 != nil {
t.Fatalf(err.Error())
}
log.Println("ERROR:", errRes.Error)
t.Fatalf(err.Error())
}
// Get UDP scrape response
scrapeRes := new(udp.ScrapeResponse)
err = scrapeRes.UnmarshalBinary(res)
if err != nil {
errRes := new(udp.ErrorResponse)
err2 := errRes.UnmarshalBinary(res)
if err2 != nil {
t.Fatalf(err.Error())
}
log.Println("ERROR:", errRes.Error)
t.Fatalf(err.Error())
}
log.Println(scrapeRes)
// Delete mock file
if err := file.Delete(); err != nil {
t.Fatalf("Failed to delete mock file: %s", err.Error())
}
}