Add lsetstat@openssh.com

encoding/ssh/filexfer/openssh/lsetstat.go

diff --git a/encoding/ssh/filexfer/openssh/lsetstat.go b/encoding/ssh/filexfer/openssh/lsetstat.go
new file mode 100644
index 0000000..2ef799e
--- /dev/null
+++ b/encoding/ssh/filexfer/openssh/lsetstat.go
@@ -0,0 +1,87 @@
+package openssh
+
+import (
+	sshfx "github.com/pkg/sftp/v2/encoding/ssh/filexfer"
+)
+
+const extensionLSetStat = "lsetstat@openssh.com"
+
+// ExtensionLSetStat returns an ExtensionPair suitable to append into an sshfx.InitPacket or sshfx.VersionPacket.
+func ExtensionLSetStat() *sshfx.ExtensionPair {
+	return &sshfx.ExtensionPair{
+		Name: extensionLSetStat,
+		Data: "1",
+	}
+}
+
+// LSetStatExtendedPacket defines the fsync@openssh.com extend packet.
+type LSetStatExtendedPacket struct {
+	Path  string
+	Attrs sshfx.Attributes
+}
+
+// Type returns the SSH_FXP_EXTENDED packet type.
+func (ep *LSetStatExtendedPacket) Type() sshfx.PacketType {
+	return sshfx.PacketTypeExtended
+}
+
+// MarshalSize returns the number of bytes that the extended request data would marshal into.
+func (ep *LSetStatExtendedPacket) MarshalSize() int {
+	// string(handle)
+	return 4 + len(ep.Path) + ep.Attrs.MarshalSize()
+}
+
+// ExtendedRequest returns the SSH_FXP_EXTENDED extended-request field associated with this packet type.
+func (ep *LSetStatExtendedPacket) ExtendedRequest() string {
+	return extensionLSetStat
+}
+
+// GetPath returns the path field of the packet.
+func (ep *LSetStatExtendedPacket) GetPath() string {
+	return ep.Path
+}
+
+// GetAttrs returns the attrs field of the packet.
+func (ep *LSetStatExtendedPacket) GetAttrs() *sshfx.Attributes {
+	return &ep.Attrs
+}
+
+// MarshalPacket returns ep as a two-part binary encoding of the full extended packet.
+func (ep *LSetStatExtendedPacket) MarshalPacket(reqid uint32, b []byte) (header, payload []byte, err error) {
+	p := &sshfx.ExtendedPacket{
+		ExtendedRequest: extensionLSetStat,
+
+		Data: ep,
+	}
+	return p.MarshalPacket(reqid, b)
+}
+
+// MarshalInto encodes ep into the binary encoding of the fsync@openssh.com extended packet-specific data.
+func (ep *LSetStatExtendedPacket) MarshalInto(buf *sshfx.Buffer) {
+	buf.AppendString(ep.Path)
+	ep.Attrs.MarshalInto(buf)
+}
+
+// MarshalBinary encodes ep into the binary encoding of the fsync@openssh.com extended packet-specific data.
+//
+// NOTE: This _only_ encodes the packet-specific data, it does not encode the full extended packet.
+func (ep *LSetStatExtendedPacket) MarshalBinary() ([]byte, error) {
+	buf := sshfx.NewMarshalBuffer(ep.MarshalSize())
+	ep.MarshalInto(buf)
+	return buf.Bytes(), nil
+}
+
+// UnmarshalFrom decodes the fsync@openssh.com extended packet-specific data from buf.
+func (ep *LSetStatExtendedPacket) UnmarshalFrom(buf *sshfx.Buffer) (err error) {
+	*ep = LSetStatExtendedPacket{
+		Path: buf.ConsumeString(),
+	}
+	ep.Attrs.UnmarshalFrom(buf)
+
+	return buf.Err
+}
+
+// UnmarshalBinary decodes the fsync@openssh.com extended packet-specific data into ep.
+func (ep *LSetStatExtendedPacket) UnmarshalBinary(data []byte) (err error) {
+	return ep.UnmarshalFrom(sshfx.NewBuffer(data))
+}