xds_end2end_test fail with OpenSSL

[Sunidhi-Gaonkar1]

What version of gRPC and what language are you using?

v1.68.2

What operating system (Linux, Windows,...) and version?

Ubuntu 22.04.5

What runtime / compiler are you using (e.g. python version or version of gcc)

gcc version 11.4.0

What did you do?

Hi Team,
We are working on building and testing grpc from source using openssl instead of borinngssl using CMake
I was able to build grpc using CMake, but noticed the follwoing test failure for xds_end2end_test.

What did you expect to see?

Test passing successfully.

What did you see instead?

Faced the following test failure:

/grpc/test/cpp/end2end/xds/xds_end2end_test.cc:1118: Failure
Value of: status.error_message()
Expected: matches regular expression "failed to connect to all addresses; last error: (UNKNOWN|UNAVAILABLE): (ipv6:%5B::1%5D|ipv4:127.0.0.1):[0-9]+: (Failed 
to connect to remote host: )?Tls handshake failed \\(TSI_PROTOCOL_FAILURE\\): SSL_ERROR_SSL: error:1000007d:SSL routines:OPENSSL_internal:CERTIFICATE_VERIFY_FAILED(: .*)?"
  Actual: "failed to connect to all addresses; last error: UNKNOWN: ipv4:127.0.0.1:2832: Tls handshake failed (TSI_PROTOCOL_FAILURE): SSL_ERROR_SSL: error:0A000086:SSL routines::certificate verify failed: self-signed certificate"
  

Attaching detailed logs below.
Any pointers regarding this will be helpful.Thank you.
logs_grpc_x86.txt

Anything else we should know about your project / environment?

[matthewstevenson88]

@gtcooke94 Can you take a look at this failure?

[gtcooke94]

Taking a look - looking at the failure, it looks like maybe we are expecting too specific of a string in the status

[matthewstevenson88]

Good eye! Yes agreed, it's likely just the different error string coming from the different SSL library. Maybe we can change the regex / expected string so that we no longer care about anything past SSL_ERROR_SSL? WDYT?

[yashykt]

I've been dealing with the flakiness in this test suite, and yes, this is one of the remaining ones.

[yashykt]

Oh, I see. You are using openssl instead of boringssl, and the expected error messages are just slightly different. These tests are usually for our CI to run, so we wouldnt expect our tests to run perfectly on all possible systems, but in this case, the change seems small enough that we can add it.