Protocol ID abbreviation

go.mod

@@ -105,3 +105,6 @@ require (
 	gopkg.in/yaml.v3 v3.0.1 // indirect
 	lukechampine.com/blake3 v1.4.1 // indirect
 )
+
+// TODO: remove this when it's done
+replace github.com/multiformats/go-multistream => github.com/ppopth/go-multistream v0.0.0-20251120232627-f8839ce1ab11

go.sum

@@ -104,8 +104,6 @@ github.com/multiformats/go-multicodec v0.9.1/go.mod h1:LLWNMtyV5ithSBUo3vFIMaeDy
 github.com/multiformats/go-multihash v0.0.8/go.mod h1:YSLudS+Pi8NHE7o6tb3D8vrpKa63epEDmG8nTduyAew=
 github.com/multiformats/go-multihash v0.2.3 h1:7Lyc8XfX/IY2jWb/gI7JP+o7JEq9hOa7BFvVU9RSh+U=
 github.com/multiformats/go-multihash v0.2.3/go.mod h1:dXgKXCXjBzdscBLk9JkjINiEsCKRVch90MdaGiKsvSM=
-github.com/multiformats/go-multistream v0.6.1 h1:4aoX5v6T+yWmc2raBHsTvzmFhOI8WVOer28DeBBEYdQ=
-github.com/multiformats/go-multistream v0.6.1/go.mod h1:ksQf6kqHAb6zIsyw7Zm+gAuVo57Qbq84E27YlYqavqw=
 github.com/multiformats/go-varint v0.0.7 h1:sWSGR+f/eu5ABZA2ZpYKBILXTTs9JWpdEM/nEGOHFS8=
 github.com/multiformats/go-varint v0.0.7/go.mod h1:r8PUYw/fD/SjBCiKOoDlGF6QawOELpZAu9eioSos/OU=
 github.com/munnerz/goautoneg v0.0.0-20191010083416-a7dc8b61c822 h1:C3w9PqII01/Oq1c1nUAm88MOHcQC9l5mIlSMApZMrHA=
@@ -156,6 +154,8 @@ github.com/pion/webrtc/v4 v4.1.2 h1:mpuUo/EJ1zMNKGE79fAdYNFZBX790KE7kQQpLMjjR54=
 github.com/pion/webrtc/v4 v4.1.2/go.mod h1:xsCXiNAmMEjIdFxAYU0MbB3RwRieJsegSB2JZsGN+8U=
 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
+github.com/ppopth/go-multistream v0.0.0-20251120232627-f8839ce1ab11 h1:gMuSK7z8Tn0w9v4BEvWkpNREQ1ntq6pTJyleZdB9fXM=
+github.com/ppopth/go-multistream v0.0.0-20251120232627-f8839ce1ab11/go.mod h1:sIFlNOs3fTbw+XPuWqQ0MgfxtPcVu5N8R5Xg5+H/bcE=
 github.com/prometheus/client_golang v1.22.0 h1:rb93p9lokFEsctTys46VnV1kLCDpVZ0a/Y92Vm0Zc6Q=
 github.com/prometheus/client_golang v1.22.0/go.mod h1:R7ljNsLXhuQXYZYtw6GAE9AZg8Y7vEW5scdCXrWRXC0=
 github.com/prometheus/client_model v0.6.2 h1:oBsgwpGs7iVziMvrGhE53c/GrLUsZdHnqNwqPLxwZyk=

p2p/host/basic/basic_host.go

@@ -481,7 +481,12 @@ func (h *BasicHost) NewStream(ctx context.Context, p peer.ID, pids ...protocol.I
 		if err := s.SetProtocol(pref); err != nil {
 			return nil, err
 		}
-		lzcon := msmux.NewMSSelect(s, pref)
+		var lzcon msmux.LazyConn
+		if h.supportProtocolAbbreviation(p) {
+			lzcon = msmux.NewMSSelect2(s, pref, pids)
+		} else {
+			lzcon = msmux.NewMSSelect(s, pref)
+		}
 		return &streamWrapper{
 			Stream: s,
 			rw:     lzcon,
@@ -528,6 +533,19 @@ func (h *BasicHost) preferredProtocol(p peer.ID, pids []protocol.ID) (protocol.I
 	return out, nil
 }
 
+func (h *BasicHost) supportProtocolAbbreviation(p peer.ID) bool {
+	mv, err := h.Peerstore().Get(p, "MaxMultiselectVersion")
+	if err != nil {
+		// if there is no value, assume it's not supported.
+		return false
+	}
+	maxVersion, ok := mv.(uint32)
+	if !ok {
+		return false
+	}
+	return maxVersion >= msmux.AbbrevSupportedMSSVersion
+}
+
 // Connect ensures there is a connection between this host and the peer with
 // given peer.ID. If there is not an active connection, Connect will issue a
 // h.Network.Dial, and block until a connection is open, or an error is returned.

p2p/protocol/identify/id.go

@@ -44,6 +44,8 @@ const (
 	DefaultTimeout = 5 * time.Second
 	// ServiceName is the default identify service name
 	ServiceName = "libp2p.identify"
+	// Maximum multistream-select version this implementation supports
+	MaxMultiselectVersion = 2
 
 	legacyIDSize          = 2 * 1024
 	signedIDSize          = 8 * 1024
@@ -151,6 +153,8 @@ type idService struct {
 	UserAgent       string
 	ProtocolVersion string
 
+	MaxMultiselectVersion uint32
+
 	metricsTracer MetricsTracer
 
 	setupCompleted chan struct{} // is closed when Start has finished setting up
@@ -204,6 +208,7 @@ func NewIDService(h host.Host, opts ...Option) (*idService, error) {
 		Host:                    h,
 		UserAgent:               userAgent,
 		ProtocolVersion:         cfg.protocolVersion,
+		MaxMultiselectVersion:   MaxMultiselectVersion,
 		ctx:                     ctx,
 		ctxCancel:               cancel,
 		conns:                   make(map[network.Conn]entry),
@@ -679,6 +684,7 @@ func (ids *idService) createBaseIdentifyResponse(conn network.Conn, snapshot *id
 	// set protocol versions
 	mes.ProtocolVersion = &ids.ProtocolVersion
 	mes.AgentVersion = &ids.UserAgent
+	mes.MaxMultiselectVersion = &ids.MaxMultiselectVersion
 
 	return mes
 }
@@ -823,9 +829,11 @@ func (ids *idService) consumeMessage(mes *pb.Identify, c network.Conn, isPush bo
 	// get protocol versions
 	pv := mes.GetProtocolVersion()
 	av := mes.GetAgentVersion()
+	mv := mes.GetMaxMultiselectVersion()
 
 	ids.Host.Peerstore().Put(p, "ProtocolVersion", pv)
 	ids.Host.Peerstore().Put(p, "AgentVersion", av)
+	ids.Host.Peerstore().Put(p, "MaxMultiselectVersion", mv)
 
 	// get the key from the other side. we may not have it (no-auth transport)
 	ids.consumeReceivedPubKey(c, mes.PublicKey)

p2p/protocol/identify/pb/identify.proto

@@ -35,4 +35,8 @@ message Identify {
   // see github.com/libp2p/go-libp2p/core/record/pb/envelope.proto and
   // github.com/libp2p/go-libp2p/core/peer/pb/peer_record.proto for message definitions.
   optional bytes signedPeerRecord = 8;
+
+  // maxMultiselectVersion contains the maximum multistream-select version the node supports.
+  // If it's absent, we assume that it's 1.
+  optional uint32 maxMultiselectVersion = 9;
 }