Implement hostname checking.
* src/x509.c (struct dn_array_s): New. (release_dn_array): New. (parse_dn_part): New. (parse_dn): New. (check_hostname): New. (_ntbtls_x509_check_hostname): New. * src/protocol.c (_ntbtls_read_certificate): Add hostname check.
The functions parse_dn and parse_dn_part are taken from current
gnupg/sm/certdump.c.
- Signed-off-by: Werner Koch <wk@gnupg.org>