/**
* Searches for a holder public key certificate and verifies its
* certification path.
*
* @param attrCert the attribute certificate.
* @param pkixParams The PKIX parameters.
* @return The certificate path of the holder certificate.
* @throws Exception if
* <ul>
* <li>no public key certificate can be found although holder
* information is given by an entity name or a base certificate
* ID</li>
* <li>support classes cannot be created</li>
* <li>no certification path for the public key certificate can
* be built</li>
* </ul>
*/
internal static PkixCertPath ProcessAttrCert1(
IX509AttributeCertificate attrCert,
PkixParameters pkixParams)
{
PkixCertPathBuilderResult result = null;
// find holder PKCs
ISet holderPKCs = new HashSet();
if (attrCert.Holder.GetIssuer() != null)
{
X509CertStoreSelector selector = new X509CertStoreSelector();
selector.SerialNumber = attrCert.Holder.SerialNumber;
X509Name[] principals = attrCert.Holder.GetIssuer();
for (int i = 0; i < principals.Length; i++)
{
try
{
// if (principals[i] is X500Principal)
{
selector.Issuer = principals[i];
}
holderPKCs.AddAll(PkixCertPathValidatorUtilities
.FindCertificates(selector, pkixParams.GetStores()));
}
catch (Exception e)
{
throw new PkixCertPathValidatorException(
"Public key certificate for attribute certificate cannot be searched.",
e);
}
}
if (holderPKCs.IsEmpty)
{
throw new PkixCertPathValidatorException(
"Public key certificate specified in base certificate ID for attribute certificate cannot be found.");
}
}
if (attrCert.Holder.GetEntityNames() != null)
{
X509CertStoreSelector selector = new X509CertStoreSelector();
X509Name[] principals = attrCert.Holder.GetEntityNames();
for (int i = 0; i < principals.Length; i++)
{
try
{
// if (principals[i] is X500Principal)
{
selector.Issuer = principals[i];
}
holderPKCs.AddAll(PkixCertPathValidatorUtilities
.FindCertificates(selector, pkixParams.GetStores()));
}
catch (Exception e)
{
throw new PkixCertPathValidatorException(
"Public key certificate for attribute certificate cannot be searched.",
e);
}
}
if (holderPKCs.IsEmpty)
{
throw new PkixCertPathValidatorException(
"Public key certificate specified in entity name for attribute certificate cannot be found.");
}
}
// verify cert paths for PKCs
PkixBuilderParameters parameters = (PkixBuilderParameters)
PkixBuilderParameters.GetInstance(pkixParams);
PkixCertPathValidatorException lastException = null;
foreach (X509Certificate cert in holderPKCs)
{
X509CertStoreSelector selector = new X509CertStoreSelector();
selector.Certificate = cert;
parameters.SetTargetConstraints(selector);
PkixCertPathBuilder builder = new PkixCertPathBuilder();
try
{
result = builder.Build(PkixBuilderParameters.GetInstance(parameters));
}
catch (PkixCertPathBuilderException e)
{
lastException = new PkixCertPathValidatorException(
"Certification path for public key certificate of attribute certificate could not be build.",
e);
}
}
if (lastException != null)
{
throw lastException;
}
return result.CertPath;
}
/**
* Obtain and validate the certification path for the complete CRL issuer.
* If a key usage extension is present in the CRL issuer's certificate,
* verify that the cRLSign bit is set.
*
* @param crl CRL which contains revocation information for the certificate
* <code>cert</code>.
* @param cert The attribute certificate or certificate to check if it is
* revoked.
* @param defaultCRLSignCert The issuer certificate of the certificate <code>cert</code>.
* @param defaultCRLSignKey The public key of the issuer certificate
* <code>defaultCRLSignCert</code>.
* @param paramsPKIX paramsPKIX PKIX parameters.
* @param certPathCerts The certificates on the certification path.
* @return A <code>Set</code> with all keys of possible CRL issuer
* certificates.
* @throws AnnotatedException if the CRL is not valid or the status cannot be checked or
* some error occurs.
*/
internal static ISet ProcessCrlF(
X509Crl crl,
object cert,
X509Certificate defaultCRLSignCert,
AsymmetricKeyParameter defaultCRLSignKey,
PkixParameters paramsPKIX,
IList certPathCerts)
{
// (f)
// get issuer from CRL
X509CertStoreSelector selector = new X509CertStoreSelector();
try
{
selector.Subject = crl.IssuerDN;
}
catch (IOException e)
{
throw new Exception(
"Subject criteria for certificate selector to find issuer certificate for CRL could not be set.", e);
}
// get CRL signing certs
IList coll = Platform.CreateArrayList();
try
{
CollectionUtilities.AddRange(coll, PkixCertPathValidatorUtilities.FindCertificates(selector, paramsPKIX.GetStores()));
CollectionUtilities.AddRange(coll, PkixCertPathValidatorUtilities.FindCertificates(selector, paramsPKIX.GetAdditionalStores()));
}
catch (Exception e)
{
throw new Exception("Issuer certificate for CRL cannot be searched.", e);
}
coll.Add(defaultCRLSignCert);
IEnumerator cert_it = coll.GetEnumerator();
IList validCerts = Platform.CreateArrayList();
IList validKeys = Platform.CreateArrayList();
while (cert_it.MoveNext())
{
X509Certificate signingCert = (X509Certificate)cert_it.Current;
/*
* CA of the certificate, for which this CRL is checked, has also
* signed CRL, so skip the path validation, because is already done
*/
if (signingCert.Equals(defaultCRLSignCert))
{
validCerts.Add(signingCert);
validKeys.Add(defaultCRLSignKey);
continue;
}
try
{
// CertPathBuilder builder = CertPathBuilder.GetInstance("PKIX");
PkixCertPathBuilder builder = new PkixCertPathBuilder();
selector = new X509CertStoreSelector();
selector.Certificate = signingCert;
PkixParameters temp = (PkixParameters)paramsPKIX.Clone();
temp.SetTargetCertConstraints(selector);
PkixBuilderParameters parameters = (PkixBuilderParameters)
PkixBuilderParameters.GetInstance(temp);
/*
* if signingCert is placed not higher on the cert path a
* dependency loop results. CRL for cert is checked, but
* signingCert is needed for checking the CRL which is dependent
* on checking cert because it is higher in the cert path and so
* signing signingCert transitively. so, revocation is disabled,
* forgery attacks of the CRL are detected in this outer loop
* for all other it must be enabled to prevent forgery attacks
*/
if (certPathCerts.Contains(signingCert))
{
parameters.IsRevocationEnabled = false;
}
else
{
parameters.IsRevocationEnabled = true;
}
IList certs = builder.Build(parameters).CertPath.Certificates;
validCerts.Add(signingCert);
validKeys.Add(PkixCertPathValidatorUtilities.GetNextWorkingKey(certs, 0));
}
catch (PkixCertPathBuilderException e)
{
throw new Exception("Internal error.", e);
}
catch (PkixCertPathValidatorException e)
{
throw new Exception("Public key of issuer certificate of CRL could not be retrieved.", e);
}
//catch (Exception e)
//{
// throw new Exception(e.Message);
//}
}
ISet checkKeys = new HashSet();
Exception lastException = null;
for (int i = 0; i < validCerts.Count; i++)
{
X509Certificate signCert = (X509Certificate)validCerts[i];
bool[] keyusage = signCert.GetKeyUsage();
if (keyusage != null && (keyusage.Length < 7 || !keyusage[CRL_SIGN]))
{
lastException = new Exception(
"Issuer certificate key usage extension does not permit CRL signing.");
}
else
{
checkKeys.Add(validKeys[i]);
}
}
if ((checkKeys.Count == 0) && lastException == null)
{
throw new Exception("Cannot find a valid issuer certificate.");
}
if ((checkKeys.Count == 0) && lastException != null)
{
throw lastException;
}
return checkKeys;
}
/**
* Searches for a holder public key certificate and verifies its
* certification path.
*
* @param attrCert the attribute certificate.
* @param pkixParams The PKIX parameters.
* @return The certificate path of the holder certificate.
* @throws Exception if
* <ul>
* <li>no public key certificate can be found although holder
* information is given by an entity name or a base certificate
* ID</li>
* <li>support classes cannot be created</li>
* <li>no certification path for the public key certificate can
* be built</li>
* </ul>
*/
internal static PkixCertPath ProcessAttrCert1(
IX509AttributeCertificate attrCert,
PkixParameters pkixParams)
{
PkixCertPathBuilderResult result = null;
// find holder PKCs
ISet holderPKCs = new HashSet();
if (attrCert.Holder.GetIssuer() != null)
{
X509CertStoreSelector selector = new X509CertStoreSelector();
selector.SerialNumber = attrCert.Holder.SerialNumber;
X509Name[] principals = attrCert.Holder.GetIssuer();
for (int i = 0; i < principals.Length; i++)
{
try
{
// if (principals[i] is X500Principal)
{
selector.Issuer = principals[i];
}
holderPKCs.AddAll(PkixCertPathValidatorUtilities
.FindCertificates(selector, pkixParams.GetStores()));
}
catch (Exception e)
{
throw new PkixCertPathValidatorException(
"Public key certificate for attribute certificate cannot be searched.",
e);
}
}
if (holderPKCs.IsEmpty)
{
throw new PkixCertPathValidatorException(
"Public key certificate specified in base certificate ID for attribute certificate cannot be found.");
}
}
if (attrCert.Holder.GetEntityNames() != null)
{
X509CertStoreSelector selector = new X509CertStoreSelector();
X509Name[] principals = attrCert.Holder.GetEntityNames();
for (int i = 0; i < principals.Length; i++)
{
try
{
// if (principals[i] is X500Principal)
{
selector.Issuer = principals[i];
}
holderPKCs.AddAll(PkixCertPathValidatorUtilities
.FindCertificates(selector, pkixParams.GetStores()));
}
catch (Exception e)
{
throw new PkixCertPathValidatorException(
"Public key certificate for attribute certificate cannot be searched.",
e);
}
}
if (holderPKCs.IsEmpty)
{
throw new PkixCertPathValidatorException(
"Public key certificate specified in entity name for attribute certificate cannot be found.");
}
}
// verify cert paths for PKCs
PkixBuilderParameters parameters = (PkixBuilderParameters)
PkixBuilderParameters.GetInstance(pkixParams);
PkixCertPathValidatorException lastException = null;
foreach (X509Certificate cert in holderPKCs)
{
X509CertStoreSelector selector = new X509CertStoreSelector();
selector.Certificate = cert;
parameters.SetTargetConstraints(selector);
PkixCertPathBuilder builder = new PkixCertPathBuilder();
try
{
result = builder.Build(PkixBuilderParameters.GetInstance(parameters));
}
catch (PkixCertPathBuilderException e)
{
lastException = new PkixCertPathValidatorException(
"Certification path for public key certificate of attribute certificate could not be build.",
e);
}
}
if (lastException != null)
{
throw lastException;
}
return(result.CertPath);
}
