```
CMake Error at CMakeLists.txt:4 (cmake_minimum_required):
Compatibility with CMake < 3.5 has been removed from CMake.
Update the VERSION argument <min> value. Or, use the <min>...<max> syntax
to tell CMake that the project requires at least <min> but has been updated
to work with policies introduced by <max> or earlier.
Or, add -DCMAKE_POLICY_VERSION_MINIMUM=3.5 to try configuring anyway.
```
This PR encompasses two complementing purposes:
A documentation on verifying an Intel SGX evidence as produced by WAMR,
including a guide for verification without an Intel SGX-enabled platform.
This also contains a small addition to the RA sample to extract specific
information, such as whether the enclave is running in debug mode.
A C# sample to verify evidence on trusted premises (and without Intel SGX).
Evidence is generated on untrusted environments, using Intel SGX.
The JSON evidence is allocated on the module instance heap, but no API
was given to dispose of this memory buffer. The sample mentions using
the function free, which behaves differently depending on the
execution context.
This fix provides a new function called librats_dispose_evidence_json,
enabling freeing the JSON evidence directly from the Wasm app.
Current SGX lib-rats wasm module hash is stored in a global buffer,
which may be overwritten if there are multiple wasm module loadings.
We move the module hash into the enclave module to resolve the issue.
And rename the SGX_IPFS macro/variable in Makefile and Enclave.edl to
make the code more consistent.
And refine the sgx-ra sample document.
The current implementation of remote attestation does not take into
account the integrity of the wasm module. The SHA256 of the wasm
module has been put into user_data to generate the quote, and more
parameters are exposed for further verification.
