Added unban peer feature

banman/store.go

@@ -66,6 +66,9 @@ type Store interface {
 
 	// Status returns the ban status for a given IP network.
 	Status(*net.IPNet) (Status, error)
+
+	// UnbanIPNet removes the ban imposed on the specified peer.
+	UnbanIPNet(ipNet *net.IPNet) error
 }
 
 // NewStore returns a Store backed by a database.
@@ -136,6 +139,38 @@ func (s *banStore) BanIPNet(ipNet *net.IPNet, reason Reason, duration time.Durat
 	})
 }
 
+// UnbanIPNet removes a ban record for the IP network within the store.
+func (s *banStore) UnbanIPNet(ipNet *net.IPNet) error {
+	err := walletdb.Update(s.db, func(tx walletdb.ReadWriteTx) error {
+		banStore := tx.ReadWriteBucket(banStoreBucket)
+		if banStore == nil {
+			return ErrCorruptedStore
+		}
+
+		banIndex := banStore.NestedReadWriteBucket(banBucket)
+		if banIndex == nil {
+			return ErrCorruptedStore
+		}
+
+		reasonIndex := banStore.NestedReadWriteBucket(reasonBucket)
+		if reasonIndex == nil {
+			return ErrCorruptedStore
+		}
+
+		var ipNetBuf bytes.Buffer
+		if err := encodeIPNet(&ipNetBuf, ipNet); err != nil {
+			return fmt.Errorf("unable to encode %v: %v", ipNet,
+				err)
+		}
+
+		k := ipNetBuf.Bytes()
+
+		return removeBannedIPNet(banIndex, reasonIndex, k)
+	})
+
+	return err
+}
+
 // addBannedIPNet adds an entry to the ban store for the given IP network.
 func addBannedIPNet(banIndex, reasonIndex walletdb.ReadWriteBucket,
 	ipNetKey []byte, reason Reason, duration time.Duration) error {

banman/store_test.go

@@ -11,6 +11,7 @@ import (
 	"github.com/btcsuite/btcwallet/walletdb"
 	_ "github.com/btcsuite/btcwallet/walletdb/bdb"
 	"github.com/lightninglabs/neutrino/banman"
+	"github.com/stretchr/testify/require"
 )
 
 // createTestBanStore creates a test Store backed by a boltdb instance.
@@ -123,4 +124,10 @@ func TestBanStore(t *testing.T) {
 	// We'll query for second IP network again as it should now be unknown
 	// to the BanStore. We should expect not to find anything regarding it.
 	checkBanStore(ipNet2, false, 0, 0)
+
+	// Test UnbanIPNet.
+	require.NoError(t, banStore.UnbanIPNet(ipNet1))
+
+	// We would now check that ipNet1 is indeed unbanned.
+	checkBanStore(ipNet1, false, 0, 0)
 }

neutrino.go

@@ -1081,6 +1081,24 @@ func (s *ChainService) BanPeer(addr string, reason banman.Reason) error {
 	return s.banStore.BanIPNet(ipNet, reason, BanDuration)
 }
 
+// UnbanPeer connects and unbans a previously banned peer.
+func (s *ChainService) UnbanPeer(addr string, parmanent bool) error {
+	log.Infof("UnBanning peer %v", addr)
+
+	ipNet, err := banman.ParseIPNet(addr, nil)
+	if err != nil {
+		return fmt.Errorf("unable to parse IP network for peer %v: %v",
+			addr, err)
+	}
+
+	err = s.banStore.UnbanIPNet(ipNet)
+	if err != nil {
+		return fmt.Errorf("unable to unban peer: %v", err)
+	}
+
+	return s.ConnectNode(addr, parmanent)
+}
+
 // IsBanned returns true if the peer is banned, and false otherwise.
 func (s *ChainService) IsBanned(addr string) bool {
 	ipNet, err := banman.ParseIPNet(addr, nil)