Previously, it was possible to use Graphene without the main executable
(e.g. having only preloaded libraries). We aren't aware of anyone using
this weird option, but worse, it led to a very bad UX when the user made
mistakes - e.g. having a typo in the manifest or executable name could
lead to Graphene starting without errors, but doing nothing.
Supporting these options complicates the design of Graphene and loading
logic significantly, providing little useful functionality:
- loader.exec:
- the main user of it were our tests
- worked only for the first process spawned inside Graphene, as it
was a unidirectional manifest->binary mapping, so the child
process didn't know about the corresponding manifest.
- sgx.sigfile:
- probably all existing usages of it were completely redundant
- was resolved relatively to CWD instead of the executable location,
which made it mostly useless
From now on, the correct location of the files is:
- either place the manifest and sigfile next to the binary, with a
matching name, or
- create a symlink to the binary in the folder where manifests are
stored and launch it through this symlink
We don't use it in tests, plus it didn't work on SGX - there was a
warning about autogeneration inserted before the autogenerated shebang.
Also, test_106_manifest_with_shebang didn't actually test the shebang
but ran the binary through the loader, so it was meaningless. We'll need
to fix it and implement again after cleaning up Graphene invocation.
Michał Kowalczyk