* nix-store --import': import an archive created by nix-store

--export' into the Nix store, and optionally check the cryptographic
  signatures against /nix/etc/nix/signing-key.pub.  (TODO: verify
  against a set of public keys.)

src/libstore/local-store.hh

@@ -59,6 +59,8 @@ public:
     void exportPath(const Path & path, bool sign,
         Sink & sink);
 
+    Path importPath(bool requireSignature, Source & source);
+    
     void buildDerivations(const PathSet & drvPaths);
 
     void ensurePath(const Path & path);