Boring SSL added the SSL_CTX_set_strict_cipher_list api a few years back this with explanation:
First, typos in cipher lists can go undetected for a long time, and
can have surprising consequences when silently ignored.
Second, there is a tendency to use superstition in the construction of
cipher lists, for example by "turning off" things that do not actually
exist. This leads to the corrosive belief that DEFAULT and ALL ought
not to be trusted. This belief is false.
This is the function here: https://github.com/google/boringssl/blob/main/include/openssl/ssl.h#L1693 . It's not present in openssl.
I think it make sense to expose it in the rust binding.