/**
* Check if the certificate allows use of the given DNS name.
*
* <p>From RFC2818: If a subjectAltName extension of type dNSName is present, that MUST be used as
* the identity. Otherwise, the (most specific) Common Name field in the Subject field of the
* certificate MUST be used. Although the use of the Common Name is existing practice, it is
* deprecated and Certification Authorities are encouraged to use the dNSName instead.
*
* <p>Matching is performed using the matching rules specified by [RFC2459]. If more than one
* identity of a given type is present in the certificate (e.g., more than one dNSName name, a
* match in any one of the set is considered acceptable.)
*/
private void matchDNS(String expectedName, X509Certificate cert) throws CertificateException {
Collection<List<?>> subjAltNames = cert.getSubjectAlternativeNames();
if (subjAltNames != null) {
boolean foundDNS = false;
for (List<?> next : subjAltNames) {
if (((Integer) next.get(0)).intValue() == ALTNAME_DNS) {
foundDNS = true;
String dnsName = (String) next.get(1);
if (isMatched(expectedName, dnsName)) {
return;
}
}
}
if (foundDNS) {
// if certificate contains any subject alt names of type DNS
// but none match, reject
throw new CertificateException(
"No subject alternative DNS " + "name matching " + expectedName + " found.");
}
}
X500Name subjectName = getSubjectX500Name(cert);
DerValue derValue = subjectName.findMostSpecificAttribute(X500Name.commonName_oid);
if (derValue != null) {
try {
if (isMatched(expectedName, derValue.getAsString())) {
return;
}
} catch (IOException e) {
// ignore
}
}
String msg = "No name matching " + expectedName + " found";
throw new CertificateException(msg);
}
