Fix Restore file to read-only node (DecomposedFS) (#1913)

changelog/unreleased/restore-readonly.md

@@ -0,0 +1,7 @@
+Bugfix: Logic to restore files to readonly nodes
+
+This impacts solely the DecomposedFS. Prior to these changes there was no validation when a user tried to restore a file from the trashbin to a share location (i.e any folder under `/Shares`).
+
+With this patch if the user restoring the resource has write permissions on the share, restore is possible.
+
+https://github.com/cs3org/reva/pull/1913

pkg/errtypes/errtypes.go

@@ -183,7 +183,7 @@ type IsChecksumMismatch interface {
 }
 
 // IsInsufficientStorage is the interface to implement
-// to specify that a there is insufficient storage.
+// to specify that there is insufficient storage.
 type IsInsufficientStorage interface {
 	IsInsufficientStorage()
 }

pkg/rgrpc/status/status.go

@@ -143,6 +143,15 @@ func NewInvalidArg(ctx context.Context, msg string) *rpc.Status {
 	}
 }
 
+// NewConflict returns a Status with Code_CODE_ABORTED and logs the msg.
+func NewConflict(ctx context.Context, err error, msg string) *rpc.Status {
+	return &rpc.Status{
+		Code:    rpc.Code_CODE_ABORTED,
+		Message: msg,
+		Trace:   getTrace(ctx),
+	}
+}
+
 // NewStatusFromErrType returns a status that corresponds to the given errtype
 func NewStatusFromErrType(ctx context.Context, msg string, err error) *rpc.Status {
 	switch e := err.(type) {

pkg/storage/utils/decomposedfs/decomposedfs.go

@@ -70,7 +70,7 @@ type Tree interface {
 	// CreateReference(ctx context.Context, node *node.Node, targetURI *url.URL) error
 	Move(ctx context.Context, oldNode *node.Node, newNode *node.Node) (err error)
 	Delete(ctx context.Context, node *node.Node) (err error)
-	RestoreRecycleItemFunc(ctx context.Context, key, trashPath, restorePath string) (*node.Node, func() error, error) // FIXME REFERENCE use ref instead of path
+	RestoreRecycleItemFunc(ctx context.Context, key, trashPath, restorePath string) (*node.Node, *node.Node, func() error, error) // FIXME REFERENCE use ref instead of path
 	PurgeRecycleItemFunc(ctx context.Context, key, purgePath string) (*node.Node, func() error, error)
 
 	WriteBlob(key string, reader io.Reader) error
@@ -191,7 +191,7 @@ func (fs *Decomposedfs) CreateHome(ctx context.Context) (err error) {
 	if n, err = fs.lu.RootNode(ctx); err != nil {
 		return
 	}
-	h, err = fs.lu.WalkPath(ctx, n, fs.lu.mustGetUserLayout(ctx), func(ctx context.Context, n *node.Node) error {
+	h, err = fs.lu.WalkPath(ctx, n, fs.lu.mustGetUserLayout(ctx), false, func(ctx context.Context, n *node.Node) error {
 		if !n.Exists {
 			if err := fs.tp.CreateDir(ctx, n); err != nil {
 				return err
@@ -344,7 +344,7 @@ func (fs *Decomposedfs) CreateReference(ctx context.Context, p string, targetURI
 
 	// create Shares folder if it does not exist
 	var n *node.Node
-	if n, err = fs.lu.NodeFromPath(ctx, fs.o.ShareFolder); err != nil {
+	if n, err = fs.lu.NodeFromPath(ctx, fs.o.ShareFolder, false); err != nil {
 		return errtypes.InternalError(err.Error())
 	} else if !n.Exists {
 		if err = fs.tp.CreateDir(ctx, n); err != nil {

pkg/storage/utils/decomposedfs/grants_test.go

@@ -102,7 +102,7 @@ var _ = Describe("Grants", func() {
 
 		Describe("AddGrant", func() {
 			It("adds grants", func() {
-				n, err := env.Lookup.NodeFromPath(env.Ctx, "/dir1")
+				n, err := env.Lookup.NodeFromPath(env.Ctx, "/dir1", false)
 				Expect(err).ToNot(HaveOccurred())
 
 				err = env.Fs.AddGrant(env.Ctx, ref, grant)

pkg/storage/utils/decomposedfs/lookup.go

@@ -30,7 +30,9 @@ import (
 	"github.com/cs3org/reva/pkg/errtypes"
 	"github.com/cs3org/reva/pkg/storage/utils/decomposedfs/node"
 	"github.com/cs3org/reva/pkg/storage/utils/decomposedfs/options"
+	"github.com/cs3org/reva/pkg/storage/utils/decomposedfs/xattrs"
 	"github.com/cs3org/reva/pkg/storage/utils/templates"
+	"github.com/pkg/xattr"
 )
 
 // Lookup implements transformations from filepath to node and back
@@ -51,7 +53,7 @@ func (lu *Lookup) NodeFromResource(ctx context.Context, ref *provider.Reference)
 		p := filepath.Clean(ref.Path)
 		if p != "." {
 			// walk the relative path
-			n, err = lu.WalkPath(ctx, n, p, func(ctx context.Context, n *node.Node) error {
+			n, err = lu.WalkPath(ctx, n, p, false, func(ctx context.Context, n *node.Node) error {
 				return nil
 			})
 			if err != nil {
@@ -64,15 +66,15 @@ func (lu *Lookup) NodeFromResource(ctx context.Context, ref *provider.Reference)
 	}
 
 	if ref.Path != "" {
-		return lu.NodeFromPath(ctx, ref.GetPath())
+		return lu.NodeFromPath(ctx, ref.GetPath(), false)
 	}
 
 	// reference is invalid
 	return nil, fmt.Errorf("invalid reference %+v. at least resource_id or path must be set", ref)
 }
 
 // NodeFromPath converts a filename into a Node
-func (lu *Lookup) NodeFromPath(ctx context.Context, fn string) (*node.Node, error) {
+func (lu *Lookup) NodeFromPath(ctx context.Context, fn string, followReferences bool) (*node.Node, error) {
 	log := appctx.GetLogger(ctx)
 	log.Debug().Interface("fn", fn).Msg("NodeFromPath()")
 
@@ -84,7 +86,7 @@ func (lu *Lookup) NodeFromPath(ctx context.Context, fn string) (*node.Node, erro
 	// TODO collect permissions of the current user on every segment
 	fn = filepath.Clean(fn)
 	if fn != "/" && fn != "." {
-		n, err = lu.WalkPath(ctx, n, fn, func(ctx context.Context, n *node.Node) error {
+		n, err = lu.WalkPath(ctx, n, fn, followReferences, func(ctx context.Context, n *node.Node) error {
 			log.Debug().Interface("node", n).Msg("NodeFromPath() walk")
 			return nil
 		})
@@ -139,20 +141,36 @@ func (lu *Lookup) HomeNode(ctx context.Context) (node *node.Node, err error) {
 	if node, err = lu.RootNode(ctx); err != nil {
 		return
 	}
-	node, err = lu.WalkPath(ctx, node, lu.mustGetUserLayout(ctx), nil)
+	node, err = lu.WalkPath(ctx, node, lu.mustGetUserLayout(ctx), false, nil)
 	return
 }
 
-// WalkPath calls n.Child(segment) on every path segment in p starting at the node r
-// If a function f is given it will be executed for every segment node, but not the root node r
-func (lu *Lookup) WalkPath(ctx context.Context, r *node.Node, p string, f func(ctx context.Context, n *node.Node) error) (*node.Node, error) {
+// WalkPath calls n.Child(segment) on every path segment in p starting at the node r.
+// If a function f is given it will be executed for every segment node, but not the root node r.
+// If followReferences is given the current visited reference node is replaced by the referenced node.
+func (lu *Lookup) WalkPath(ctx context.Context, r *node.Node, p string, followReferences bool, f func(ctx context.Context, n *node.Node) error) (*node.Node, error) {
 	segments := strings.Split(strings.Trim(p, "/"), "/")
 	var err error
 	for i := range segments {
 		if r, err = r.Child(ctx, segments[i]); err != nil {
 			return r, err
 		}
-		// if an intermediate node is missing return not found
+
+		if followReferences {
+			if attrBytes, err := xattr.Get(r.InternalPath(), xattrs.ReferenceAttr); err == nil {
+				realNodeID := attrBytes
+				ref, err := xattrs.ReferenceFromAttr(realNodeID)
+				if err != nil {
+					return nil, err
+				}
+
+				r, err = lu.NodeFromID(ctx, ref.ResourceId)
+				if err != nil {
+					return nil, err
+				}
+			}
+		}
+
 		if !r.Exists && i < len(segments)-1 {
 			return r, errtypes.NotFound(segments[i])
 		}

pkg/storage/utils/decomposedfs/lookup_test.go

@@ -20,6 +20,7 @@ package decomposedfs_test
 
 import (
 	helpers "github.com/cs3org/reva/pkg/storage/utils/decomposedfs/testhelpers"
+	"github.com/cs3org/reva/pkg/storage/utils/decomposedfs/xattrs"
 
 	. "github.com/onsi/ginkgo"
 	. "github.com/onsi/gomega"
@@ -40,16 +41,28 @@ var _ = Describe("Lookup", func() {
 		if env != nil {
 			env.Cleanup()
 		}
+
 	})
 
 	Describe("Path", func() {
 		It("returns the path including a leading slash", func() {
-			n, err := env.Lookup.NodeFromPath(env.Ctx, "/dir1/file1")
+			n, err := env.Lookup.NodeFromPath(env.Ctx, "/dir1/file1", false)
 			Expect(err).ToNot(HaveOccurred())
 
 			path, err := env.Lookup.Path(env.Ctx, n)
 			Expect(err).ToNot(HaveOccurred())
 			Expect(path).To(Equal("/dir1/file1"))
 		})
 	})
+
+	Describe("Reference Parsing", func() {
+		It("parses a valid cs3 reference", func() {
+			in := []byte("cs3:bede11a0-ea3d-11eb-a78b-bf907adce8ed/c402d01c-ea3d-11eb-a0fc-c32f9d32528f")
+			ref, err := xattrs.ReferenceFromAttr(in)
+
+			Expect(err).ToNot(HaveOccurred())
+			Expect(ref.ResourceId.StorageId).To(Equal("bede11a0-ea3d-11eb-a78b-bf907adce8ed"))
+			Expect(ref.ResourceId.OpaqueId).To(Equal("c402d01c-ea3d-11eb-a0fc-c32f9d32528f"))
+		})
+	})
 })

pkg/storage/utils/decomposedfs/node/node.go

@@ -103,6 +103,23 @@ func New(id, parentID, name string, blobsize int64, blobID string, owner *userpb
 	}
 }
 
+// ChangeOwner sets the owner of n to newOwner
+func (n *Node) ChangeOwner(new *userpb.UserId) (err error) {
+	nodePath := n.InternalPath()
+	n.owner = new
+	if err = xattr.Set(nodePath, xattrs.OwnerIDAttr, []byte(new.OpaqueId)); err != nil {
+		return errors.Wrap(err, "Decomposedfs: could not reset owner id attribute")
+	}
+	if err = xattr.Set(nodePath, xattrs.OwnerIDPAttr, []byte(new.Idp)); err != nil {
+		return errors.Wrap(err, "Decomposedfs: could not reset owner idp attribute")
+	}
+	if err = xattr.Set(nodePath, xattrs.OwnerTypeAttr, []byte(utils.UserTypeToString(new.Type))); err != nil {
+		return errors.Wrap(err, "Decomposedfs: could not reset owner idp attribute")
+	}
+
+	return
+}
+
 // WriteMetadata writes the Node metadata to disk
 func (n *Node) WriteMetadata(owner *userpb.UserId) (err error) {
 	nodePath := n.InternalPath()

pkg/storage/utils/decomposedfs/node/node_test.go

@@ -64,7 +64,7 @@ var _ = Describe("Node", func() {
 
 	Describe("ReadNode", func() {
 		It("reads the blobID from the xattrs", func() {
-			lookupNode, err := env.Lookup.NodeFromPath(env.Ctx, "/dir1/file1")
+			lookupNode, err := env.Lookup.NodeFromPath(env.Ctx, "/dir1/file1", false)
 			Expect(err).ToNot(HaveOccurred())
 
 			n, err := node.ReadNode(env.Ctx, env.Lookup, lookupNode.ID)
@@ -75,7 +75,7 @@ var _ = Describe("Node", func() {
 
 	Describe("WriteMetadata", func() {
 		It("writes all xattrs", func() {
-			n, err := env.Lookup.NodeFromPath(env.Ctx, "/dir1/file1")
+			n, err := env.Lookup.NodeFromPath(env.Ctx, "/dir1/file1", false)
 			Expect(err).ToNot(HaveOccurred())
 
 			blobsize := 239485734
@@ -90,7 +90,7 @@ var _ = Describe("Node", func() {
 
 			err = n.WriteMetadata(owner)
 			Expect(err).ToNot(HaveOccurred())
-			n2, err := env.Lookup.NodeFromPath(env.Ctx, "/dir1/file1")
+			n2, err := env.Lookup.NodeFromPath(env.Ctx, "/dir1/file1", false)
 			Expect(err).ToNot(HaveOccurred())
 			Expect(n2.Name).To(Equal("TestName"))
 			Expect(n2.BlobID).To(Equal("TestBlobID"))
@@ -100,7 +100,7 @@ var _ = Describe("Node", func() {
 
 	Describe("Parent", func() {
 		It("returns the parent node", func() {
-			child, err := env.Lookup.NodeFromPath(env.Ctx, "/dir1/subdir1")
+			child, err := env.Lookup.NodeFromPath(env.Ctx, "/dir1/subdir1", false)
 			Expect(err).ToNot(HaveOccurred())
 			Expect(child).ToNot(BeNil())
 
@@ -118,7 +118,7 @@ var _ = Describe("Node", func() {
 
 		BeforeEach(func() {
 			var err error
-			parent, err = env.Lookup.NodeFromPath(env.Ctx, "/dir1")
+			parent, err = env.Lookup.NodeFromPath(env.Ctx, "/dir1", false)
 			Expect(err).ToNot(HaveOccurred())
 			Expect(parent).ToNot(BeNil())
 		})
@@ -165,7 +165,7 @@ var _ = Describe("Node", func() {
 
 		BeforeEach(func() {
 			var err error
-			n, err = env.Lookup.NodeFromPath(env.Ctx, "dir1/file1")
+			n, err = env.Lookup.NodeFromPath(env.Ctx, "dir1/file1", false)
 			Expect(err).ToNot(HaveOccurred())
 		})
 

pkg/storage/utils/decomposedfs/recycle.go

@@ -262,7 +262,7 @@ func (fs *Decomposedfs) RestoreRecycleItem(ctx context.Context, key, path string
 	if restoreRef == nil {
 		restoreRef = &provider.Reference{}
 	}
-	rn, restoreFunc, err := fs.tp.RestoreRecycleItemFunc(ctx, key, path, restoreRef.Path)
+	rn, p, restoreFunc, err := fs.tp.RestoreRecycleItemFunc(ctx, key, path, restoreRef.Path)
 	if err != nil {
 		return err
 	}
@@ -278,6 +278,16 @@ func (fs *Decomposedfs) RestoreRecycleItem(ctx context.Context, key, path string
 		return errtypes.PermissionDenied(key)
 	}
 
+	ps, err := fs.p.AssemblePermissions(ctx, p)
+	if err != nil {
+		return errtypes.InternalError(err.Error())
+	}
+
+	// share receiver cannot restore to a shared resource to which she does not have write permissions.
+	if !ps.InitiateFileUpload {
+		return errtypes.PermissionDenied(key)
+	}
+
 	// Run the restore func
 	return restoreFunc()
 }

pkg/storage/utils/decomposedfs/testhelpers/helpers.go

@@ -150,7 +150,7 @@ func (t *TestEnv) CreateTestDir(name string) (*node.Node, error) {
 	if err != nil {
 		return nil, err
 	}
-	n, err := t.Lookup.NodeFromPath(t.Ctx, name)
+	n, err := t.Lookup.NodeFromPath(t.Ctx, name, false)
 	if err != nil {
 		return nil, err
 	}

pkg/storage/utils/decomposedfs/tree/tree.go

@@ -59,7 +59,7 @@ type Blobstore interface {
 
 // PathLookup defines the interface for the lookup component
 type PathLookup interface {
-	NodeFromPath(ctx context.Context, fn string) (*node.Node, error)
+	NodeFromPath(ctx context.Context, fn string, followReferences bool) (*node.Node, error)
 	NodeFromID(ctx context.Context, id *provider.ResourceId) (n *node.Node, err error)
 	RootNode(ctx context.Context) (node *node.Node, err error)
 	HomeOrRootNode(ctx context.Context) (node *node.Node, err error)
@@ -446,25 +446,35 @@ func (t *Tree) Delete(ctx context.Context, n *node.Node) (err error) {
 	return t.Propagate(ctx, n)
 }
 
-// RestoreRecycleItemFunc returns a node and a function to restore it from the trash
-func (t *Tree) RestoreRecycleItemFunc(ctx context.Context, key, trashPath, restorePath string) (*node.Node, func() error, error) {
+// RestoreRecycleItemFunc returns a node and a function to restore it from the trash.
+func (t *Tree) RestoreRecycleItemFunc(ctx context.Context, key, trashPath, restorePath string) (*node.Node, *node.Node, func() error, error) {
 	rn, trashItem, deletedNodePath, origin, err := t.readRecycleItem(ctx, key, trashPath)
 	if err != nil {
-		return nil, nil, err
+		return nil, nil, nil, err
 	}
 
 	if restorePath == "" {
 		restorePath = origin
 	}
 
+	var target *node.Node
+	target, err = t.lookup.NodeFromPath(ctx, restorePath, true)
+	if err != nil {
+		return nil, nil, nil, err
+	}
+
+	p, err := target.Parent()
+	if err != nil {
+		return nil, nil, nil, err
+	}
+
 	fn := func() error {
 		// link to origin
 		var n *node.Node
-		n, err = t.lookup.NodeFromPath(ctx, restorePath)
+		n, err = t.lookup.NodeFromPath(ctx, restorePath, true)
 		if err != nil {
 			return err
 		}
-
 		if n.Exists {
 			return errtypes.AlreadyExists("origin already exists")
 		}
@@ -486,6 +496,21 @@ func (t *Tree) RestoreRecycleItemFunc(ctx context.Context, key, trashPath, resto
 			}
 		}
 
+		// the new node will inherit the permissions of its parent
+		p, err := n.Parent()
+		if err != nil {
+			return err
+		}
+
+		po, err := p.Owner()
+		if err != nil {
+			return err
+		}
+
+		if err := rn.ChangeOwner(po); err != nil {
+			return err
+		}
+
 		n.Exists = true
 		// update name attribute
 		if err := xattr.Set(nodePath, xattrs.NameAttr, []byte(n.Name)); err != nil {
@@ -505,7 +530,7 @@ func (t *Tree) RestoreRecycleItemFunc(ctx context.Context, key, trashPath, resto
 		}
 		return t.Propagate(ctx, n)
 	}
-	return rn, fn, nil
+	return rn, p, fn, nil
 }
 
 // PurgeRecycleItemFunc returns a node and a function to purge it from the trash