First-pass DP PR

[FishmanL]

The code is relatively simple -- I just used the RGSL package for laplacian noise which I generate, take the absolute value of, double (since I'm only taking 1 tail) and then subtract it from the distance before comparing it to the minimum.

[lacabra]

Thanks @FishmanL, I've taken a look at your PR. I've made some small adjustments but this PR won't compile because the RGSL library depends on features from the std library which are not available inside SGX, and that one cannot disable.

@reuvenpo do you have any suggestions?

[FishmanL]

https://software.intel.com/en-us/forums/intel-software-guard-extensions-intel-sgx/topic/748096 seems relevant?

[lacabra]

Possibly. That's outside my knowledge of SGX+Rust. That's why I tagged Reuven in my previous comment. I'll let him respond.

[assafmo]

Hi @FishmanL, we can only use no_std-enabled crates inside the enclave, so please use a GSL library with no_std support and make sure the project compiles on your machine. 😊