/* * Copyright (c) 2002, 2012, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. Oracle designates this * particular file as subject to the "Classpath" exception as provided * by Oracle in the LICENSE file that accompanied this code. * * This code is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. */ package sun.security.validator; import java.io.IOException; import java.util.*; import java.security.*; import java.security.cert.*; import javax.security.auth.x500.X500Principal; import sun.security.x509.X509CertImpl; import sun.security.x509.NetscapeCertTypeExtension; import sun.security.util.DerValue; import sun.security.util.DerInputStream; import sun.security.util.DerOutputStream; import sun.security.util.ObjectIdentifier; import sun.security.provider.certpath.AlgorithmChecker; import sun.security.provider.certpath.UntrustedChecker; /** * A simple validator implementation. It is based on code from the JSSE * X509TrustManagerImpl. This implementation is designed for compatibility with * deployed certificates and previous J2SE versions. It will never support * more advanced features and will be deemphasized in favor of the PKIX * validator going forward. *

* {@code SimpleValidator} objects are immutable once they have been created. * Please DO NOT add methods that can change the state of an instance once * it has been created. * * @author Andreas Sterbenz */ public final class SimpleValidator extends Validator { // Constants for the OIDs we need final static String OID_BASIC_CONSTRAINTS = "2.5.29.19"; final static String OID_NETSCAPE_CERT_TYPE = "2.16.840.1.113730.1.1"; final static String OID_KEY_USAGE = "2.5.29.15"; final static String OID_EXTENDED_KEY_USAGE = "2.5.29.37"; final static String OID_EKU_ANY_USAGE = "2.5.29.37.0"; final static ObjectIdentifier OBJID_NETSCAPE_CERT_TYPE = NetscapeCertTypeExtension.NetscapeCertType_Id; private final static String NSCT_SSL_CA = NetscapeCertTypeExtension.SSL_CA; private final static String NSCT_CODE_SIGNING_CA = NetscapeCertTypeExtension.OBJECT_SIGNING_CA; /** * The trusted certificates as: * Map (X500Principal)subject of trusted cert -> List of X509Certificate * The list is used because there may be multiple certificates * with an identical subject DN. */ private final Map> trustedX500Principals; /** * Set of the trusted certificates. Present only for * getTrustedCertificates(). */ private final Collection trustedCerts; SimpleValidator(String variant, Collection trustedCerts) { super(TYPE_SIMPLE, variant); this.trustedCerts = trustedCerts; trustedX500Principals = new HashMap>(); for (X509Certificate cert : trustedCerts) { X500Principal principal = cert.getSubjectX500Principal(); List list = trustedX500Principals.get(principal); if (list == null) { // this actually should be a set, but duplicate entries // are not a problem and we can avoid the Set overhead list = new ArrayList(2); trustedX500Principals.put(principal, list); } list.add(cert); } } public Collection getTrustedCertificates() { return trustedCerts; } /** * Perform simple validation of chain. The arguments otherCerts and * parameter are ignored. */ @Override X509Certificate[] engineValidate(X509Certificate[] chain, Collection otherCerts, AlgorithmConstraints constraints, Object parameter) throws CertificateException { if ((chain == null) || (chain.length == 0)) { throw new CertificateException ("null or zero-length certificate chain"); } // make sure chain includes a trusted cert chain = buildTrustedChain(chain); Date date = validationDate; if (date == null) { date = new Date(); } // create distrusted certificates checker UntrustedChecker untrustedChecker = new UntrustedChecker(); // create default algorithm constraints checker TrustAnchor anchor = new TrustAnchor(chain[chain.length - 1], null); AlgorithmChecker defaultAlgChecker = new AlgorithmChecker(anchor); // create application level algorithm constraints checker AlgorithmChecker appAlgChecker = null; if (constraints != null) { appAlgChecker = new AlgorithmChecker(anchor, constraints); } // verify top down, starting at the certificate issued by // the trust anchor int maxPathLength = chain.length - 1; for (int i = chain.length - 2; i >= 0; i--) { X509Certificate issuerCert = chain[i + 1]; X509Certificate cert = chain[i]; // check untrusted certificate try { // Untrusted checker does not care about the unresolved // critical extensions. untrustedChecker.check(cert, Collections.emptySet()); } catch (CertPathValidatorException cpve) { throw new ValidatorException( "Untrusted certificate: " + cert.getSubjectX500Principal(), ValidatorException.T_UNTRUSTED_CERT, cert, cpve); } // check certificate algorithm try { // Algorithm checker does not care about the unresolved // critical extensions. defaultAlgChecker.check(cert, Collections.emptySet()); if (appAlgChecker != null) { appAlgChecker.check(cert, Collections.emptySet()); } } catch (CertPathValidatorException cpve) { throw new ValidatorException (ValidatorException.T_ALGORITHM_DISABLED, cert, cpve); } // no validity check for code signing certs if ((variant.equals(VAR_CODE_SIGNING) == false) && (variant.equals(VAR_JCE_SIGNING) == false)) { cert.checkValidity(date); } // check name chaining if (cert.getIssuerX500Principal().equals( issuerCert.getSubjectX500Principal()) == false) { throw new ValidatorException (ValidatorException.T_NAME_CHAINING, cert); } // check signature try { cert.verify(issuerCert.getPublicKey()); } catch (GeneralSecurityException e) { throw new ValidatorException (ValidatorException.T_SIGNATURE_ERROR, cert, e); } // check extensions for CA certs if (i != 0) { maxPathLength = checkExtensions(cert, maxPathLength); } } return chain; } private int checkExtensions(X509Certificate cert, int maxPathLen) throws CertificateException { Set critSet = cert.getCriticalExtensionOIDs(); if (critSet == null) { critSet = Collections.emptySet(); } // Check the basic constraints extension int pathLenConstraint = checkBasicConstraints(cert, critSet, maxPathLen); // Check the key usage and extended key usage extensions checkKeyUsage(cert, critSet); // check Netscape certificate type extension checkNetscapeCertType(cert, critSet); if (!critSet.isEmpty()) { throw new ValidatorException ("Certificate contains unknown critical extensions: " + critSet, ValidatorException.T_CA_EXTENSIONS, cert); } return pathLenConstraint; } private void checkNetscapeCertType(X509Certificate cert, Set critSet) throws CertificateException { if (variant.equals(VAR_GENERIC)) { // nothing } else if (variant.equals(VAR_TLS_CLIENT) || variant.equals(VAR_TLS_SERVER)) { if (getNetscapeCertTypeBit(cert, NSCT_SSL_CA) == false) { throw new ValidatorException ("Invalid Netscape CertType extension for SSL CA " + "certificate", ValidatorException.T_CA_EXTENSIONS, cert); } critSet.remove(OID_NETSCAPE_CERT_TYPE); } else if (variant.equals(VAR_CODE_SIGNING) || variant.equals(VAR_JCE_SIGNING)) { if (getNetscapeCertTypeBit(cert, NSCT_CODE_SIGNING_CA) == false) { throw new ValidatorException ("Invalid Netscape CertType extension for code " + "signing CA certificate", ValidatorException.T_CA_EXTENSIONS, cert); } critSet.remove(OID_NETSCAPE_CERT_TYPE); } else { throw new CertificateException("Unknown variant " + variant); } } /** * Get the value of the specified bit in the Netscape certificate type * extension. If the extension is not present at all, we return true. */ static boolean getNetscapeCertTypeBit(X509Certificate cert, String type) { try { NetscapeCertTypeExtension ext; if (cert instanceof X509CertImpl) { X509CertImpl certImpl = (X509CertImpl)cert; ObjectIdentifier oid = OBJID_NETSCAPE_CERT_TYPE; ext = (NetscapeCertTypeExtension)certImpl.getExtension(oid); if (ext == null) { return true; } } else { byte[] extVal = cert.getExtensionValue(OID_NETSCAPE_CERT_TYPE); if (extVal == null) { return true; } DerInputStream in = new DerInputStream(extVal); byte[] encoded = in.getOctetString(); encoded = new DerValue(encoded).getUnalignedBitString() .toByteArray(); ext = new NetscapeCertTypeExtension(encoded); } Boolean val = (Boolean)ext.get(type); return val.booleanValue(); } catch (IOException e) { return false; } } private int checkBasicConstraints(X509Certificate cert, Set critSet, int maxPathLen) throws CertificateException { critSet.remove(OID_BASIC_CONSTRAINTS); int constraints = cert.getBasicConstraints(); // reject, if extension missing or not a CA (constraints == -1) if (constraints < 0) { throw new ValidatorException("End user tried to act as a CA", ValidatorException.T_CA_EXTENSIONS, cert); } // if the certificate is self-issued, ignore the pathLenConstraint // checking. if (!X509CertImpl.isSelfIssued(cert)) { if (maxPathLen <= 0) { throw new ValidatorException("Violated path length constraints", ValidatorException.T_CA_EXTENSIONS, cert); } maxPathLen--; } if (maxPathLen > constraints) { maxPathLen = constraints; } return maxPathLen; } /* * Verify the key usage and extended key usage for intermediate * certificates. */ private void checkKeyUsage(X509Certificate cert, Set critSet) throws CertificateException { critSet.remove(OID_KEY_USAGE); // EKU irrelevant in CA certificates critSet.remove(OID_EXTENDED_KEY_USAGE); // check key usage extension boolean[] keyUsageInfo = cert.getKeyUsage(); if (keyUsageInfo != null) { // keyUsageInfo[5] is for keyCertSign. if ((keyUsageInfo.length < 6) || (keyUsageInfo[5] == false)) { throw new ValidatorException ("Wrong key usage: expected keyCertSign", ValidatorException.T_CA_EXTENSIONS, cert); } } } /** * Build a trusted certificate chain. This method always returns a chain * with a trust anchor as the final cert in the chain. If no trust anchor * could be found, a CertificateException is thrown. */ private X509Certificate[] buildTrustedChain(X509Certificate[] chain) throws CertificateException { List c = new ArrayList(chain.length); // scan chain starting at EE cert // if a trusted certificate is found, append it and return for (int i = 0; i < chain.length; i++) { X509Certificate cert = chain[i]; X509Certificate trustedCert = getTrustedCertificate(cert); if (trustedCert != null) { c.add(trustedCert); return c.toArray(CHAIN0); } c.add(cert); } // check if we can append a trusted cert X509Certificate cert = chain[chain.length - 1]; X500Principal subject = cert.getSubjectX500Principal(); X500Principal issuer = cert.getIssuerX500Principal(); List list = trustedX500Principals.get(issuer); if (list != null) { X509Certificate trustedCert = list.iterator().next(); c.add(trustedCert); return c.toArray(CHAIN0); } // no trusted cert found, error throw new ValidatorException(ValidatorException.T_NO_TRUST_ANCHOR); } /** * Return a trusted certificate that matches the input certificate, * or null if no such certificate can be found. This method also handles * cases where a CA re-issues a trust anchor with the same public key and * same subject and issuer names but a new validity period, etc. */ private X509Certificate getTrustedCertificate(X509Certificate cert) { Principal certSubjectName = cert.getSubjectX500Principal(); List list = trustedX500Principals.get(certSubjectName); if (list == null) { return null; } Principal certIssuerName = cert.getIssuerX500Principal(); PublicKey certPublicKey = cert.getPublicKey(); for (X509Certificate mycert : list) { if (mycert.equals(cert)) { return cert; } if (!mycert.getIssuerX500Principal().equals(certIssuerName)) { continue; } if (!mycert.getPublicKey().equals(certPublicKey)) { continue; } // All tests pass, this must be the one to use... return mycert; } return null; } }