multi: add new config option `upfront-shutdown-address`

diff --git a/config.go b/config.go
index 6d5bc54..e9ce410 100644
--- a/config.go
+++ b/config.go
@@ -537,6 +537,15 @@ type Config struct {
 	// NoDisconnectOnPongFailure controls if we'll disconnect if a peer
 	// doesn't respond to a pong in time.
 	NoDisconnectOnPongFailure bool `long:"no-disconnect-on-pong-failure" description:"If true, a peer will *not* be disconnected if a pong is not received in time or is mismatched. Defaults to false, meaning peers *will* be disconnected on pong failure."`
+
+	// UpfrontShutdownAddr specifies an address that our funds will be paid
+	// out to on cooperative channel close. This applies to all new channel
+	// opens unless overridden by an option in openchannel or by a channel
+	// acceptor.
+	// Note: If this field is set when opening a channel with a peer that
+	// does not advertise support for the upfront shutdown feature, the
+	// channel open will fail.
+	UpfrontShutdownAddr string `long:"upfront-shutdown-address" description:"The address to which funds will be paid out during a cooperative channel close. This applies to all channels opened after this option is set, unless overridden for a specific channel opening. Note: If this option is set, any channel opening will fail if the peer does not explicitly advertise support for the upfront-shutdown feature bit."`
 }
 
 // GRPCConfig holds the configuration options for the gRPC server.
diff --git a/funding/manager.go b/funding/manager.go
index 8176e6a..5711ed8 100644
--- a/funding/manager.go
+++ b/funding/manager.go
@@ -573,6 +573,10 @@ type Config struct {
 	// implementations to inject and process custom records over channel
 	// related wire messages.
 	AuxChannelNegotiator fn.Option[lnwallet.AuxChannelNegotiator]
+
+	// ShutdownScript is an optional upfront-shutdown script to which our
+	// funds should be paid on a cooperative close.
+	ShutdownScript fn.Option[lnwire.DeliveryAddress]
 }
 
 // Manager acts as an orchestrator/bridge between the wallet's
@@ -1760,12 +1764,24 @@ func (f *Manager) fundeeProcessOpenChannel(peer lnpeer.Peer,
 		return
 	}
 
+	// If the fundee didn't provide an upfront-shutdown address via
+	// the channel acceptor, fall back to the configured shutdown
+	// script (if any).
+	shutdownScript := acceptorResp.UpfrontShutdown
+	if len(shutdownScript) == 0 {
+		f.cfg.ShutdownScript.WhenSome(
+			func(script lnwire.DeliveryAddress) {
+				shutdownScript = script
+			},
+		)
+	}
+
 	// Check whether the peer supports upfront shutdown, and get a new
 	// wallet address if our node is configured to set shutdown addresses by
 	// default. We use the upfront shutdown script provided by our channel
 	// acceptor (if any) in lieu of user input.
 	shutdown, err := getUpfrontShutdownScript(
-		f.cfg.EnableUpfrontShutdown, peer, acceptorResp.UpfrontShutdown,
+		f.cfg.EnableUpfrontShutdown, peer, shutdownScript,
 		f.selectShutdownScript,
 	)
 	if err != nil {
@@ -4849,12 +4865,23 @@ func (f *Manager) handleInitFundingMsg(msg *InitFundingMsg) {
 		}
 	}
 
+	// If the funder did not provide an upfront-shutdown address, fall back
+	// to the configured shutdown script (if any).
+	shutdownScript := msg.ShutdownScript
+	if len(shutdownScript) == 0 {
+		f.cfg.ShutdownScript.WhenSome(
+			func(script lnwire.DeliveryAddress) {
+				shutdownScript = script
+			},
+		)
+	}
+
 	// Check whether the peer supports upfront shutdown, and get an address
 	// which should be used (either a user specified address or a new
 	// address from the wallet if our node is configured to set shutdown
 	// address by default).
 	shutdown, err := getUpfrontShutdownScript(
-		f.cfg.EnableUpfrontShutdown, msg.Peer, msg.ShutdownScript,
+		f.cfg.EnableUpfrontShutdown, msg.Peer, shutdownScript,
 		f.selectShutdownScript,
 	)
 	if err != nil {
diff --git a/peer/brontide.go b/peer/brontide.go
index 4a196fb..8d02ca6 100644
--- a/peer/brontide.go
+++ b/peer/brontide.go
@@ -3589,9 +3589,9 @@ func (p *Brontide) initNegotiateChanCloser(req *htlcswitch.ChanClose,
 	return nil
 }
 
-// chooseAddr returns the provided address if it is non-zero length, otherwise
+// ChooseAddr returns the provided address if it is non-zero length, otherwise
 // None.
-func chooseAddr(addr lnwire.DeliveryAddress) fn.Option[lnwire.DeliveryAddress] {
+func ChooseAddr(addr lnwire.DeliveryAddress) fn.Option[lnwire.DeliveryAddress] {
 	if len(addr) == 0 {
 		return fn.None[lnwire.DeliveryAddress]()
 	}
@@ -3930,10 +3930,10 @@ func (p *Brontide) initRbfChanCloser(
 		ChanType:       channel.ChanType(),
 		DefaultFeeRate: defaultFeePerKw.FeePerVByte(),
 		ThawHeight:     fn.Some(thawHeight),
-		RemoteUpfrontShutdown: chooseAddr(
+		RemoteUpfrontShutdown: ChooseAddr(
 			channel.RemoteUpfrontShutdownScript(),
 		),
-		LocalUpfrontShutdown: chooseAddr(
+		LocalUpfrontShutdown: ChooseAddr(
 			channel.LocalUpfrontShutdownScript(),
 		),
 		NewDeliveryScript: func() (lnwire.DeliveryAddress, error) {
diff --git a/sample-lnd.conf b/sample-lnd.conf
index c3b3a96..ed5dabd 100644
--- a/sample-lnd.conf
+++ b/sample-lnd.conf
@@ -589,6 +589,15 @@
 ; pong failure.
 ; no-disconnect-on-pong-failure=false
 
+; The address to which funds will be paid out during a cooperative channel
+; close. This applies to all channels opened after this option is set, unless
+; overridden for a specific channel opening.
+;
+; Note: If this option is set, any channel opening will fail if the peer does
+; not explicitly advertise support for the upfront-shutdown feature bit.
+; upfront-shutdown-address=
+
+
 [fee]
 
 ; Optional URL for external fee estimation. If no URL is specified, the method
diff --git a/server.go b/server.go
index d0289de..3c011f8 100644
--- a/server.go
+++ b/server.go
@@ -61,6 +61,7 @@ import (
 	"github.com/lightningnetwork/lnd/lnutils"
 	"github.com/lightningnetwork/lnd/lnwallet"
 	"github.com/lightningnetwork/lnd/lnwallet/chainfee"
+	"github.com/lightningnetwork/lnd/lnwallet/chancloser"
 	"github.com/lightningnetwork/lnd/lnwallet/chanfunding"
 	"github.com/lightningnetwork/lnd/lnwallet/rpcwallet"
 	"github.com/lightningnetwork/lnd/lnwire"
@@ -1445,6 +1446,15 @@ func newServer(ctx context.Context, cfg *Config, listenAddrs []net.Addr,
 			devCfg, reservationTimeout, zombieSweeperInterval)
 	}
 
+	// Attempt to parse the provided upfront-shutdown address (if any).
+	script, err := chancloser.ParseUpfrontShutdownAddress(
+		cfg.UpfrontShutdownAddr, cfg.ActiveNetParams.Params,
+	)
+	if err != nil {
+		return nil, fmt.Errorf("error parsing upfront shutdown: %w",
+			err)
+	}
+
 	//nolint:ll
 	s.fundingMgr, err = funding.NewFundingManager(funding.Config{
 		Dev:                devCfg,
@@ -1623,6 +1633,7 @@ func newServer(ctx context.Context, cfg *Config, listenAddrs []net.Addr,
 		AuxSigner:            implCfg.AuxSigner,
 		AuxResolver:          implCfg.AuxContractResolver,
 		AuxChannelNegotiator: implCfg.AuxChannelNegotiator,
+		ShutdownScript:       peer.ChooseAddr(script),
 	})
 	if err != nil {
 		return nil, err