Michał Kowalczyk
3d31f2d18d
This is the next part of the great loader rework, with a lot of breaking changes: - Complete removal of the "trusted children" thing - now children processes can be spawned arbitrarily and from arbitrary mountpoint types, without any additional configuration needed. - There's a new, required option in the manifest: `libos.entrypoint` - it specifies the URI to the entry binary in the first process. There's no need anymore to name the manifest and the first binary identically. - On SGX, the main binary is not measured in MRENCLAVE anymore - only PAL, LibOS and the manifest are measured. This is enough to bind MRENCLAVE to a specific entrypoint user executable if wanted - it just has to be mounted as a trusted file. - All Graphene SGX enclaves have now exactly the same MRENCLAVE. This is a hash of a "Graphene stub", which can "fork" into one of two states in runtime: initial process or child. The initial process creates a new "Graphene namespace" with a clean state, it can also be attested remotely (contrary to child processes). The initial process can spawn children processes by spawning a Graphene stub and directing it to start in the child mode. It then attests it locally, and if successful, establishes an encrypted pipe, "connects" to its own namespace and treats as trusted (including sending protected files key). - Now, there's only one, central manifest describing the initial state of a Graphene instance which can be spawned from it (previously, each process required a separate manifest which could have different configuration - which wasn't actually supported and didn't make sense design-wise). One downside of central manifests is that all processes require the same enclave configuration (e.g. size), but that was already the case so far because of broken checkpointing code. Also, this is only a temporary problem, which will cease to exist after the introduction of EDMM. - `sgx.static_address` was renamed to `sgx.nonpie_binary` and now has to be inserted manually by users (`sgx_sign` tools doesn't know about the binaries run inside, which can be even provided or generated in runtime by the user's workload). - Caveat: the memory gap for non-PIE executables was removed because it requires adding a new option to the manifest to be cleanly implemented. This is left for some future loader rework PR.
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Introduction
TODO: this example should be reworked to use a standalone gcc version, not the one from the system and readded to Jenkins
This directory contains a Makefile and template manifests to run gcc and its related tools on Graphene. We tested with gcc version 5.5.0 and binutils (as, ld) version 2.26.1 on Ubuntu 16.04. We also tested on Ubuntu 18.04 with gcc version 7.4.0 and binutils version 2.30. This example uses the package version of gcc and related tools (as, cc1, collect2, ld) installed on the system instead of compiling them from source as some of the other examples do.
The Makefile and the template manifest contain comments to hopefully make them easier to understand.
Quick Start
To run the regression tests execute make check. To do the same for SGX, execute SGX=1 make check. The regression tests build three sample programs - helloworld.c, bzip2.c and gzip.c - and
test their functionality.
By looking at the Makefile "check" target you can see how gcc is invoked to compile individual source files under the hood. If you want to compile different and/or more complex applications, you would likely need to tweak the manifest files to whitelist additional files.