Fix import-from-derivation in restricted eval mode

This relaxes restricted mode to allow access to anything in the
store. In the future, it would be better to allow access to only paths
that have been constructed in the current evaluation (so a hard-coded
/nix/store/blabla in a Nix expression would still be
rejected). However, note that reading /nix/store itself is still
rejected, so you can't use this so get access to things you don't know
about.

1 files changed, 7 insertions, 0 deletions

diff --git a/src/libexpr/eval.cc b/src/libexpr/eval.cc
index 301f991b7..88cf9f453 100644
--- a/src/libexpr/eval.cc
+++ b/src/libexpr/eval.cc
@@ -292,10 +292,17 @@ Path EvalState::checkSourcePath(const Path & path_)
         if (path == i.second || isInDir(path, i.second))
             return path;
 
+    /* To support import-from-derivation, allow access to anything in
+       the store. FIXME: only allow access to paths that have been
+       constructed by this evaluation. */
+    if (isInStore(path)) return path;
+
+#if 0
     /* Hack to support the chroot dependencies of corepkgs (see
        corepkgs/config.nix.in). */
     if (path == settings.nixPrefix && isStorePath(settings.nixPrefix))
         return path;
+#endif
 
     throw RestrictedPathError(format("access to path ‘%1%’ is forbidden in restricted mode") % path_);
 }