2 files changed, 80 insertions, 2 deletions
diff --git a/internal/fusefrontend/node_helpers.go b/internal/fusefrontend/node_helpers.go
index 96c0961..3102275 100644
--- a/internal/fusefrontend/node_helpers.go
+++ b/internal/fusefrontend/node_helpers.go
@@ -53,9 +53,9 @@ func (n *Node) readlink(dirfd int, cName string) (out []byte, errno syscall.Errn
 	return []byte(target), 0
 }
 
-// translateSize translates the ciphertext size in `out` into plaintext size.
+// translateSize translates the ciphertext size cSize into plaintext size.
 // Handles regular files & symlinks (and finds out what is what by looking at
-// `out.Mode`).
+// mode).
 func (n *Node) translateSize(dirfd int, cName string, mode uint32, cSize uint64) (pSize uint64) {
 	switch mode & syscall.S_IFMT {
 	case syscall.S_IFREG:
diff --git a/internal/fusefrontend/statx_linux.go b/internal/fusefrontend/statx_linux.go
new file mode 100644
index 0000000..f9f87cf
--- /dev/null
+++ b/internal/fusefrontend/statx_linux.go
@@ -0,0 +1,78 @@
+package fusefrontend
+
+import (
+	"context"
+	"syscall"
+
+	"github.com/hanwen/go-fuse/v2/fs"
+	"github.com/hanwen/go-fuse/v2/fuse"
+	"golang.org/x/sys/unix"
+
+	"github.com/rfjakob/gocryptfs/v2/internal/inomap"
+	"github.com/rfjakob/gocryptfs/v2/internal/syscallcompat"
+)
+
+var _ = (fs.NodeStatxer)((*Node)(nil))
+var _ = (fs.FileStatxer)((*File)(nil))
+
+// Statx is the Linux statx equivalent of Getattr.
+func (n *Node) Statx(ctx context.Context, f fs.FileHandle, flags uint32, mask uint32, out *fuse.StatxOut) (errno syscall.Errno) {
+	// If the kernel gives us a file handle, use it. Current Linux kernels do
+	// not send one with FUSE_STATX, but keep this for future compatibility.
+	if f != nil {
+		if fsx, ok := f.(fs.FileStatxer); ok {
+			return fsx.Statx(ctx, flags, mask, out)
+		}
+	}
+
+	dirfd, cName, errno := n.prepareAtSyscallMyself()
+	if errno != 0 {
+		return errno
+	}
+	defer syscall.Close(dirfd)
+
+	var st unix.Statx_t
+	err := syscallcompat.Statx(dirfd, cName, int(flags)|unix.AT_SYMLINK_NOFOLLOW, int(mask), &st)
+	if err != nil {
+		return fs.ToErrno(err)
+	}
+
+	// fix inode number, size, owner
+	rn := n.rootNode()
+	st.Ino = rn.inoMap.Translate(inomap.NewQIno(unix.Mkdev(st.Dev_major, st.Dev_minor), 0, st.Ino))
+	st.Size = rn.translateSize(dirfd, cName, uint32(st.Mode), st.Size)
+	if rn.args.ForceOwner != nil {
+		st.Uid = rn.args.ForceOwner.Uid
+		st.Gid = rn.args.ForceOwner.Gid
+	}
+
+	out.FromStatx(&st)
+	return 0
+}
+
+// Statx returns statx information for an open backing file. Current Linux
+// kernels do not send a file handle with FUSE_STATX, so this is not reached yet.
+func (f *File) Statx(_ context.Context, flags uint32, mask uint32, out *fuse.StatxOut) syscall.Errno {
+	f.fdLock.RLock()
+	defer f.fdLock.RUnlock()
+
+	var st unix.Statx_t
+	err := syscallcompat.Statx(f.intFd(), "", int(flags)|unix.AT_EMPTY_PATH, int(mask), &st)
+	if err != nil {
+		return fs.ToErrno(err)
+	}
+
+	// fix inode number, size, owner
+	rn := f.rootNode
+	st.Ino = rn.inoMap.Translate(inomap.NewQIno(unix.Mkdev(st.Dev_major, st.Dev_minor), 0, st.Ino))
+	if uint32(st.Mode)&syscall.S_IFMT == syscall.S_IFREG {
+		st.Size = rn.contentEnc.CipherSizeToPlainSize(st.Size)
+	}
+	if rn.args.ForceOwner != nil {
+		st.Uid = rn.args.ForceOwner.Uid
+		st.Gid = rn.args.ForceOwner.Gid
+	}
+
+	out.FromStatx(&st)
+	return 0
+}