def _dnsname_match(dn, hostname, max_wildcards=1):
 pats = []
 if (not dn):
  return False
 parts = dn.split('.')
 leftmost = parts[0]
 wildcards = leftmost.count('*')
 if (wildcards > max_wildcards):
  raise CertificateError(('too many wildcards in certificate DNS name: ' + repr(dn)))
 if (not wildcards):
  return (dn.lower() == hostname.lower())
 if (leftmost == '*'):
  pats.append('[^.]+')
 elif (leftmost.startswith('xn--') or hostname.startswith('xn--')):
  pats.append(re.escape(leftmost))
 else:
  pats.append(re.escape(leftmost).replace('\\*', '[^.]*'))
 for frag in parts[1:]:
  pats.append(re.escape(frag))
 pat = re.compile((('\\A' + '\\.'.join(pats)) + '\\Z'), re.IGNORECASE)
 return pat.match(hostname)

def _dnsname_match ( dn , hostname , max_wildcards = 1 ) : pats = [ ] if ( not dn ) : return False parts = dn . split ( '.' ) leftmost = parts [ 0 ] wildcards = leftmost . count ( '*' ) if ( wildcards > max_wildcards ) : raise CertificateError ( ( 'too many wildcards in certificate DNS name: ' + repr ( dn ) ) ) if ( not wildcards ) : return ( dn . lower ( ) == hostname . lower ( ) ) if ( leftmost == '*' ) : pats . append ( '[^.]+' ) elif ( leftmost . startswith ( 'xn--' ) or hostname . startswith ( 'xn--' ) ) : pats . append ( re . escape ( leftmost ) ) else : pats . append ( re . escape ( leftmost ) . replace ( '\\*' , '[^.]*' ) ) for frag in parts [ 1 : ] : pats . append ( re . escape ( frag ) ) pat = re . compile ( ( ( '\\A' + '\\.' . join ( pats ) ) + '\\Z' ) , re . IGNORECASE ) return pat . match ( hostname )
matching according to rfc 6125 .