pull: Add OSTREE_REPO_PULL_FLAGS_UNTRUSTED flag

If this is set we verify all objects we pull, even for local remotes,
and we avoid hard-linking into local source repos.

https://bugzilla.gnome.org/show_bug.cgi?id=764125

Closes: #221
Approved by: cgwalters

src/libostree/ostree-repo.h

@@ -423,6 +423,14 @@ gboolean      ostree_repo_import_object_from (OstreeRepo           *self,
                                               const char           *checksum,
                                               GCancellable         *cancellable,
                                               GError              **error);
+_OSTREE_PUBLIC
+gboolean      ostree_repo_import_object_from_with_trust (OstreeRepo           *self,
+                                                         OstreeRepo           *source,
+                                                         OstreeObjectType      objtype,
+                                                         const char           *checksum,
+                                                         gboolean              trusted,
+                                                         GCancellable         *cancellable,
+                                                         GError              **error);
 
 _OSTREE_PUBLIC
 gboolean      ostree_repo_delete_object (OstreeRepo           *self,
@@ -891,11 +899,13 @@ gboolean ostree_repo_prune (OstreeRepo        *self,
  * @OSTREE_REPO_PULL_FLAGS_NONE: No special options for pull
  * @OSTREE_REPO_PULL_FLAGS_MIRROR: Write out refs suitable for mirrors
  * @OSTREE_REPO_PULL_FLAGS_COMMIT_ONLY: Fetch only the commit metadata
+ * @OSTREE_REPO_PULL_FLAGS_UNTRUSTED: Don't trust local remote
  */
 typedef enum {
   OSTREE_REPO_PULL_FLAGS_NONE,
   OSTREE_REPO_PULL_FLAGS_MIRROR = (1 << 0),
-  OSTREE_REPO_PULL_FLAGS_COMMIT_ONLY = (1 << 1)
+  OSTREE_REPO_PULL_FLAGS_COMMIT_ONLY = (1 << 1),
+  OSTREE_REPO_PULL_FLAGS_UNTRUSTED = (1 << 2)
 } OstreeRepoPullFlags;
 
 _OSTREE_PUBLIC