From d317dfc06923318b1033c4dbdada7bf8f7776e6f Mon Sep 17 00:00:00 2001
From: Jimmy Zelinskie <jimmyzelinskie@gmail.com>
Date: Sat, 4 Apr 2015 15:41:58 -0400
Subject: [PATCH] udp: implement BEP45 response
---
udp/protocol.go | 1 +
udp/writer.go | 54 ++++++++++++++++++++++++++++++++++++++++---------
2 files changed, 45 insertions(+), 10 deletions(-)
diff --git a/udp/protocol.go b/udp/protocol.go
index ae40632..c236e79 100644
--- a/udp/protocol.go
+++ b/udp/protocol.go
@@ -18,6 +18,7 @@ const (
announceActionID
scrapeActionID
errorActionID
+ announceDualStackActionID
)
var (
diff --git a/udp/writer.go b/udp/writer.go
index b28fd8a..86e0d50 100644
--- a/udp/writer.go
+++ b/udp/writer.go
@@ -28,14 +28,33 @@ func (w *Writer) WriteError(err error) error {
return nil
}
-// WriteAnnounce encodes an announce response according to the UDP spec.
-func (w *Writer) WriteAnnounce(res *models.AnnounceResponse) error {
- w.writeHeader(announceActionID)
- binary.Write(w.buf, binary.BigEndian, uint32(res.Interval/time.Second))
- binary.Write(w.buf, binary.BigEndian, uint32(res.Incomplete))
- binary.Write(w.buf, binary.BigEndian, uint32(res.Complete))
+// WriteAnnounce encodes an announce response by selecting the proper announce
+// format based on the BitTorrent spec.
+func (w *Writer) WriteAnnounce(resp *models.AnnounceResponse) (err error) {
+ if resp.Announce.HasIPv6() {
+ err = w.WriteAnnounceIPv6(resp)
+ } else {
+ err = w.WriteAnnounceIPv4(resp)
+ }
- for _, peer := range res.IPv4Peers {
+ return
+}
+
+// WriteAnnounceIPv6 encodes an announce response according to BEP45.
+func (w *Writer) WriteAnnounceIPv6(resp *models.AnnounceResponse) error {
+ w.writeHeader(announceDualStackActionID)
+ binary.Write(w.buf, binary.BigEndian, uint32(resp.Interval/time.Second))
+ binary.Write(w.buf, binary.BigEndian, uint32(resp.Incomplete))
+ binary.Write(w.buf, binary.BigEndian, uint32(resp.Complete))
+ binary.Write(w.buf, binary.BigEndian, uint32(len(resp.IPv4Peers)))
+ binary.Write(w.buf, binary.BigEndian, uint32(len(resp.IPv6Peers)))
+
+ for _, peer := range resp.IPv4Peers {
+ w.buf.Write(peer.IP)
+ binary.Write(w.buf, binary.BigEndian, peer.Port)
+ }
+
+ for _, peer := range resp.IPv6Peers {
w.buf.Write(peer.IP)
binary.Write(w.buf, binary.BigEndian, peer.Port)
}
@@ -43,11 +62,26 @@ func (w *Writer) WriteAnnounce(res *models.AnnounceResponse) error {
return nil
}
-// WriteScrape encodes a scrape response according to the UDP spec.
-func (w *Writer) WriteScrape(res *models.ScrapeResponse) error {
+// WriteAnnounceIPv4 encodes an announce response according to BEP15.
+func (w *Writer) WriteAnnounceIPv4(resp *models.AnnounceResponse) error {
+ w.writeHeader(announceActionID)
+ binary.Write(w.buf, binary.BigEndian, uint32(resp.Interval/time.Second))
+ binary.Write(w.buf, binary.BigEndian, uint32(resp.Incomplete))
+ binary.Write(w.buf, binary.BigEndian, uint32(resp.Complete))
+
+ for _, peer := range resp.IPv4Peers {
+ w.buf.Write(peer.IP)
+ binary.Write(w.buf, binary.BigEndian, peer.Port)
+ }
+
+ return nil
+}
+
+// WriteScrape encodes a scrape response according to BEP15.
+func (w *Writer) WriteScrape(resp *models.ScrapeResponse) error {
w.writeHeader(scrapeActionID)
- for _, torrent := range res.Files {
+ for _, torrent := range resp.Files {
binary.Write(w.buf, binary.BigEndian, uint32(torrent.Seeders.Len()))
binary.Write(w.buf, binary.BigEndian, uint32(torrent.Snatches))
binary.Write(w.buf, binary.BigEndian, uint32(torrent.Leechers.Len()))