Generic solution to map Openssl to boringssl

[Sunidhi Gaonkar]

Hello,

We are working on building grpc on ppc64le architecture using OpenSSL instead of boringssl, as boringssl doesn't work on Power. We were able to avoid the boringssl dependency after using system installed openssl, as below:

https://github.com/ray-project/ray/commit/c6f9d6a3914b98c490913751c9e3c090b830264b

But there are third party dependencies like 'google_cloud_cpp' that use boringssl, which causes build failure. We can remove boringssl from that dependency too, but this will not be a long-term solution as if new dependency is added which brings in boringssl, and then the build will again fail on Power.
So, we are trying to implement a generic solution so that boringssl is mapped to system OpenSSL based on a conditional flag which will be set only for Power (as of now).We are also trying to use configurable build attribute(--define) to use openssl for power in bazel build.
Is there a way to use the system installed openssl in bazel for all dependencies instead of boringssl? Any pointers will be helpful. 

Link to issue opened in grpc repository: Generic solution to map Openssl to boringssl. · Issue #37910 · grpc/grpc (github.com)


Thank you,

Sunidhi Gaonkar.