From: Matt Joiner <anacrolix@gmail.com>
Date: Thu, 14 Aug 2025 02:30:34 +0000 (+1000)
Subject: Don't close webseed peers for bad data
X-Git-Tag: v1.59.0~2^2~9
X-Git-Url: http://www.git.stargrave.org/?a=commitdiff_plain;h=4031ab24b007c36944d1b24016147e4ac3d2619d;p=btrtrc.git

Don't close webseed peers for bad data
---

diff --git a/peer-impl.go b/peer-impl.go
index 27be7b06..25fe5a72 100644
--- a/peer-impl.go
+++ b/peer-impl.go
@@ -31,7 +31,7 @@ type legacyPeerImpl interface {
 	// Drop connection. This may be a no-op if there is no connection.
 	drop()
 	// Rebuke the peer
-	ban()
+	providedBadData()
 	String() string
 	// Per peer-impl lines for WriteStatus.
 	peerImplStatusLines() []string
diff --git a/peerconn.go b/peerconn.go
index 9758cbd2..573ae30e 100644
--- a/peerconn.go
+++ b/peerconn.go
@@ -1165,7 +1165,7 @@ func (cn *PeerConn) drop() {
 	cn.t.dropConnection(cn)
 }
 
-func (cn *PeerConn) ban() {
+func (cn *PeerConn) providedBadData() {
 	cn.t.cl.banPeerIP(cn.remoteIp())
 }
 
diff --git a/smartban.go b/smartban.go
index 857ca291..dd7d6662 100644
--- a/smartban.go
+++ b/smartban.go
@@ -11,6 +11,7 @@ import (
 
 type bannableAddr = netip.Addr
 
+// TODO: Should be keyed on weak[Peer].
 type smartBanCache = smartban.Cache[bannableAddr, RequestIndex, uint64]
 
 type blockCheckingWriter struct {
diff --git a/torrent.go b/torrent.go
index 2f6b7b98..d66d51da 100644
--- a/torrent.go
+++ b/torrent.go
@@ -1232,7 +1232,8 @@ func (t *Torrent) countBytesHashed(n int64) {
 
 func (t *Torrent) hashPiece(piece pieceIndex) (
 	correct bool,
-	// These are peers that sent us blocks that differ from what we hash here.
+	// These are peers that sent us blocks that differ from what we hash here. TODO: Track Peer not
+	// bannable addr for peer types that are rebuked differently.
 	differingPeers map[bannableAddr]struct{},
 	err error,
 ) {
@@ -2625,7 +2626,7 @@ func (t *Torrent) pieceHashed(piece pieceIndex, passed bool, hashIoErr error) {
 						"piece failed hash. banning peer",
 						"piece", piece,
 						"peer", c)
-					c.ban()
+					c.providedBadData()
 					// TODO: Check if we now have no available peers for pieces we want.
 				}
 			}
diff --git a/webseed-peer.go b/webseed-peer.go
index 19ace314..2ebfd66c 100644
--- a/webseed-peer.go
+++ b/webseed-peer.go
@@ -23,15 +23,30 @@ import (
 
 type webseedPeer struct {
 	// First field for stats alignment.
-	peer             Peer
-	logger           *slog.Logger
-	client           webseed.Client
-	activeRequests   map[*webseedRequest]struct{}
-	locker           sync.Locker
-	lastUnhandledErr time.Time
-	hostKey          webseedHostKeyHandle
+	peer           Peer
+	logger         *slog.Logger
+	client         webseed.Client
+	activeRequests map[*webseedRequest]struct{}
+	locker         sync.Locker
+	hostKey        webseedHostKeyHandle
 	// We need this to look ourselves up in the Client.activeWebseedRequests map.
 	url webseedUrlKey
+
+	// When requests are allowed to resume. If Zero, then anytime.
+	penanceComplete time.Time
+	lastCrime       error
+}
+
+func (me *webseedPeer) suspended() bool {
+	return me.lastCrime != nil && time.Now().Before(me.penanceComplete)
+}
+
+func (me *webseedPeer) convict(err error, term time.Duration) {
+	if me.suspended() {
+		return
+	}
+	me.lastCrime = err
+	me.penanceComplete = time.Now().Add(term)
 }
 
 func (*webseedPeer) allConnStatsImplField(stats *AllConnStats) *ConnStats {
@@ -78,7 +93,12 @@ var _ legacyPeerImpl = (*webseedPeer)(nil)
 func (me *webseedPeer) peerImplStatusLines() []string {
 	lines := []string{
 		me.client.Url,
-		fmt.Sprintf("last unhandled error: %v", eventAgeString(me.lastUnhandledErr)),
+	}
+	if me.lastCrime != nil {
+		lines = append(lines, fmt.Sprintf("last crime: %v", me.lastCrime))
+	}
+	if me.suspended() {
+		lines = append(lines, fmt.Sprintf("suspended for %v more", time.Until(me.penanceComplete)))
 	}
 	if len(me.activeRequests) > 0 {
 		elems := make([]string, 0, len(me.activeRequests))
@@ -238,8 +258,8 @@ func (ws *webseedPeer) connectionFlags() string {
 // Maybe this should drop all existing connections, or something like that.
 func (ws *webseedPeer) drop() {}
 
-func (cn *webseedPeer) ban() {
-	cn.peer.close()
+func (cn *webseedPeer) providedBadData() {
+	cn.convict(errors.New("provided bad data"), time.Minute)
 }
 
 func (ws *webseedPeer) onClose() {
diff --git a/webseed-requesting.go b/webseed-requesting.go
index 3bd95f50..4cc9ccb4 100644
--- a/webseed-requesting.go
+++ b/webseed-requesting.go
@@ -384,6 +384,9 @@ func (cl *Client) iterPossibleWebseedRequests() iter.Seq2[webseedUniqueRequestKe
 					panicif.GreaterThanOrEqual(firstRequest, t.maxEndRequest())
 					webseedSliceIndex := t.requestIndexToWebseedSliceIndex(firstRequest)
 					for url, ws := range t.webSeeds {
+						if ws.suspended() {
+							continue
+						}
 						// Return value from this function (RequestPieceFunc) doesn't terminate
 						// iteration, so propagate that to not handling the yield return value.
 						if !yield(