add various checks for malformedness to static check_chain_extensions() in x509_vfc.c
improve error reporting of X509v3_cache_extensions() in v3_purp.c
add error reporting to x509_init_sig_info() in x509_set.c
improve static setup_dp() and related functions in v3_purp.c and v3_crld.c
add test case for non-conforming cert from https://tools.ietf.org/html/rfc8410#section-10.2
Reviewed-by: Kurt Roeckx <kurt@roeckx.be>
Reviewed-by: Tomas Mraz <tmraz@fedoraproject.org>
(Merged from https://github.com/openssl/openssl/pull/12478)
