3 files changed, 19 insertions, 0 deletions
diff --git a/internal/fusefrontend/args.go b/internal/fusefrontend/args.go
index 5781db8..37f4463 100644
--- a/internal/fusefrontend/args.go
+++ b/internal/fusefrontend/args.go
@@ -1,6 +1,7 @@
 package fusefrontend
 
 import (
+	"github.com/hanwen/go-fuse/fuse"
 	"github.com/rfjakob/gocryptfs/internal/cryptocore"
 )
 
@@ -16,6 +17,12 @@ type Args struct {
 	// Should we chown a file after it has been created?
 	// This only makes sense if (1) allow_other is set and (2) we run as root.
 	PreserveOwner bool
+	// Should we force ownership to be presented with a given user and group?
+	// This only makes sense if allow_other is set. In *most* cases, it also
+	// only makes sense with PreserveOwner set, but can also make sense without
+	// PreserveOwner if the underlying filesystem acting as backing store
+	// enforces ownership itself.
+	ForceOwner *fuse.Owner
 	// ConfigCustom is true when the user select a non-default config file
 	// location. If it is false, reverse mode maps ".gocryptfs.reverse.conf"
 	// to "gocryptfs.conf" in the plaintext dir.
diff --git a/internal/fusefrontend/fs.go b/internal/fusefrontend/fs.go
index c589302..16707d6 100644
--- a/internal/fusefrontend/fs.go
+++ b/internal/fusefrontend/fs.go
@@ -77,6 +77,9 @@ func (fs *FS) GetAttr(name string, context *fuse.Context) (*fuse.Attr, fuse.Stat
 		target, _ := fs.Readlink(name, context)
 		a.Size = uint64(len(target))
 	}
+	if fs.args.ForceOwner != nil {
+		a.Owner = *fs.args.ForceOwner
+	}
 	return a, status
 }
 
diff --git a/internal/fusefrontend_reverse/rfs.go b/internal/fusefrontend_reverse/rfs.go
index 63384ac..3c84e15 100644
--- a/internal/fusefrontend_reverse/rfs.go
+++ b/internal/fusefrontend_reverse/rfs.go
@@ -115,6 +115,9 @@ func (rfs *ReverseFS) GetAttr(relPath string, context *fuse.Context) (*fuse.Attr
 		}
 		var a fuse.Attr
 		a.FromStat(&st)
+		if rfs.args.ForceOwner != nil {
+			a.Owner = *rfs.args.ForceOwner
+		}
 		return &a, fuse.OK
 	}
 	// Handle virtual files (gocryptfs.diriv, *.name)
@@ -136,6 +139,9 @@ func (rfs *ReverseFS) GetAttr(relPath string, context *fuse.Context) (*fuse.Attr
 		}
 		var a fuse.Attr
 		status = f.GetAttr(&a)
+		if rfs.args.ForceOwner != nil {
+			a.Owner = *rfs.args.ForceOwner
+		}
 		return &a, status
 	}
 	// Decrypt path to "plaintext relative path"
@@ -177,6 +183,9 @@ func (rfs *ReverseFS) GetAttr(relPath string, context *fuse.Context) (*fuse.Attr
 
 		a.Size = uint64(len(linkTarget))
 	}
+	if rfs.args.ForceOwner != nil {
+		a.Owner = *rfs.args.ForceOwner
+	}
 	return &a, fuse.OK
 }