OpenSSL 1.1.0: Missing setters in X509_STORE_CTX

In OpenSSL 1.1.0 the following getter functions exist for the X509_STORE_CTX (see include/openssl/x509_vfy.h):

X509_STORE_CTX_verify_fn X509_STORE_CTX_get_verify(X509_STORE_CTX *ctx);
X509_STORE_CTX_get_issuer_fn X509_STORE_CTX_get_get_issuer(X509_STORE_CTX *ctx);
X509_STORE_CTX_check_issued_fn X509_STORE_CTX_get_check_issued(X509_STORE_CTX *ctx);
X509_STORE_CTX_check_revocation_fn X509_STORE_CTX_get_check_revocation(X509_STORE_CTX *ctx);
X509_STORE_CTX_get_crl_fn X509_STORE_CTX_get_get_crl(X509_STORE_CTX *ctx);
X509_STORE_CTX_check_crl_fn X509_STORE_CTX_get_check_crl(X509_STORE_CTX *ctx);
X509_STORE_CTX_cert_crl_fn X509_STORE_CTX_get_cert_crl(X509_STORE_CTX *ctx);
X509_STORE_CTX_check_policy_fn X509_STORE_CTX_get_check_policy(X509_STORE_CTX *ctx);
X509_STORE_CTX_lookup_certs_fn X509_STORE_CTX_get_lookup_certs(X509_STORE_CTX *ctx);
X509_STORE_CTX_lookup_crls_fn X509_STORE_CTX_get_lookup_crls(X509_STORE_CTX *ctx);
X509_STORE_CTX_cleanup_fn X509_STORE_CTX_get_cleanup(X509_STORE_CTX *ctx);

But there are no corresponding setter functions. My concrete use case is to retrieve the cert_crl function pointer and wrap it into a function of my own. This was possible with OpenSSL 1.0.2, but no longer with OpenSSL 1.1.0.

See also the discussion with @richsalz on the openssl-users mailing list.

Start with the X509_STORE_CTX callback declarations in include/openssl/x509_vfy.h and read the linked openssl-users discussion for the API context. Review the existing getter set, then determine the corresponding setter coverage needed for callbacks such as cert_crl. Done means the requested setters are available and the stated cert_crl wrapping use case is supported.