Specifically, an ASN.1 NumericString in the certificate CN will fail UTF-8 conversion
and result in a negative return value, which the "x509 -checkhost" command-line option
incorrectly interpreted as success.
Also update X509_check_host docs to reflect reality.
Thanks to Sean Burford (Google) for reporting this issue.
Reviewed-by: Richard Levitte <levitte@openssl.org>
Reduces number of silly casts in OpenSSL code and likely most
applications. Consistent with (char *) for "peername" value from
X509_check_host() and X509_VERIFY_PARAM_get0_peername().
A client reference identity of ".example.com" matches a server
certificate presented identity that is any sub-domain of "example.com"
(e.g. "www.sub.example.com).
With the X509_CHECK_FLAG_SINGLE_LABEL_SUBDOMAINS flag, it matches
only direct child sub-domains (e.g. "www.sub.example.com").
Contributed by: Florian Weimer <fweimer@redhat.com>
Fixes to X509 hostname and email address checking. Wildcard matching support.
New test program and manual page.
