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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
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* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
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*
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* 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).
*
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package sun.security.provider.certpath;
import java.io.IOException;
import java.security.AccessController;
import java.security.GeneralSecurityException;
import java.security.cert.*;
import java.util.*;
import javax.security.auth.x500.X500Principal;
import sun.security.action.GetBooleanAction;
import sun.security.util.Debug;
import sun.security.x509.GeneralNames;
import sun.security.x509.GeneralNameInterface;
import sun.security.x509.GeneralSubtrees;
import sun.security.x509.NameConstraintsExtension;
import sun.security.x509.SubjectAlternativeNameExtension;
import sun.security.x509.X500Name;
import sun.security.x509.X509CertImpl;
/**
* Abstract class representing a builder, which is able to retrieve
* matching certificates and is able to verify a particular certificate.
*
* @since 1.4
* @author Sean Mullan
* @author Yassir Elley
*/
public abstract class Builder {
private static final Debug debug = Debug.getInstance("certpath");
private Set<String> matchingPolicies;
final PKIXBuilderParameters buildParams;
final X500Principal targetSubjectDN;
final Date date;
final X509CertSelector targetCertConstraints;
/**
* Flag indicating whether support for the caIssuers field of the
* Authority Information Access extension shall be enabled. Currently
* disabled by default for compatibility reasons.
*/
final static boolean USE_AIA = AccessController.doPrivileged
(new GetBooleanAction("com.sun.security.enableAIAcaIssuers"));
/**
* Initialize the builder with the input parameters.
*
* @param params the parameter set used to build a certification path
*/
Builder(PKIXBuilderParameters buildParams, X500Principal targetSubjectDN) {
this.buildParams = buildParams;
this.targetSubjectDN = targetSubjectDN;
// Initialize date if not specified
Date paramsDate = buildParams.getDate();
this.date = paramsDate != null ? paramsDate : new Date();
this.targetCertConstraints =
(X509CertSelector) buildParams.getTargetCertConstraints();
}
/**
* Retrieves certificates from the list of certStores using the buildParams
* and the currentState as a filter
*
* @param currentState the current State
* @param certStores list of CertStores
*/
abstract Collection<X509Certificate> getMatchingCerts
(State currentState, List<CertStore> certStores)
throws CertStoreException, CertificateException, IOException;
/**
* Verifies the cert against the currentState, using the certPathList
* generated thus far to help with loop detection
*
* @param cert the certificate to be verified
* @param currentState the current state against which the cert is verified
* @param certPathList the certPathList generated thus far
*/
abstract void verifyCert(X509Certificate cert, State currentState,
List<X509Certificate> certPathList) throws GeneralSecurityException;
/**
* Verifies whether the input certificate completes the path.
* When building forward, a trust anchor will complete the path.
* When building reverse, the target certificate will complete the path.
*
* @param cert the certificate to test
* @return a boolean value indicating whether the cert completes the path.
*/
abstract boolean isPathCompleted(X509Certificate cert);
/**
* Adds the certificate to the certPathList
*
* @param cert the certificate to be added
* @param certPathList the certification path list
*/
abstract void addCertToPath(X509Certificate cert,
LinkedList<X509Certificate> certPathList);
/**
* Removes final certificate from the certPathList
*
* @param certPathList the certification path list
*/
abstract void removeFinalCertFromPath
(LinkedList<X509Certificate> certPathList);
/**
* get distance of one GeneralName from another
*
* @param base GeneralName at base of subtree
* @param test GeneralName to be tested against base
* @param incomparable the value to return if the names are
* incomparable
* @return distance of test name from base, where 0
* means exact match, 1 means test is an immediate
* child of base, 2 means test is a grandchild, etc.
* -1 means test is a parent of base, -2 means test
* is a grandparent, etc.
*/
static int distance(GeneralNameInterface base,
GeneralNameInterface test, int incomparable) {
switch (base.constrains(test)) {
case GeneralNameInterface.NAME_DIFF_TYPE:
if (debug != null) {
debug.println("Builder.distance(): Names are different types");
}
case GeneralNameInterface.NAME_SAME_TYPE:
if (debug != null) {
debug.println("Builder.distance(): Names are same type but " +
"in different subtrees");
}
return incomparable;
case GeneralNameInterface.NAME_MATCH:
return 0;
case GeneralNameInterface.NAME_WIDENS:
break;
case GeneralNameInterface.NAME_NARROWS:
break;
default: // should never occur
return incomparable;
}
/* names are in same subtree */
return test.subtreeDepth() - base.subtreeDepth();
}
/**
* get hop distance of one GeneralName from another in links where
* the names need not have an ancestor/descendant relationship.
* For example, the hop distance from ou=D,ou=C,o=B,c=US to
* ou=F,ou=E,ou=C,o=B,c=US is 3: D->C, C->E, E->F. The hop distance
* from ou=C,o=B,c=US to ou=D,ou=C,o=B,c=US is -1: C->D
*
* @param base GeneralName
* @param test GeneralName to be tested against base
* @param incomparable the value to return if the names are
* incomparable
* @return distance of test name from base measured in hops in the
* namespace hierarchy, where 0 means exact match. Result
* is positive if path is some number of up hops followed by
* some number of down hops; result is negative if path is
* some number of down hops.
*/
static int hops(GeneralNameInterface base, GeneralNameInterface test,
int incomparable) {
int baseRtest = base.constrains(test);
switch (baseRtest) {
case GeneralNameInterface.NAME_DIFF_TYPE:
if (debug != null) {
debug.println("Builder.hops(): Names are different types");
}
return incomparable;
case GeneralNameInterface.NAME_SAME_TYPE:
/* base and test are in different subtrees */
break;
case GeneralNameInterface.NAME_MATCH:
/* base matches test */
return 0;
case GeneralNameInterface.NAME_WIDENS:
/* base is ancestor of test */
return (test.subtreeDepth()-base.subtreeDepth());
case GeneralNameInterface.NAME_NARROWS:
/* base is descendant of test */
return (test.subtreeDepth()-base.subtreeDepth());
default: // should never occur
return incomparable;
}
/* names are in different subtrees */
if (base.getType() != GeneralNameInterface.NAME_DIRECTORY) {
if (debug != null) {
debug.println("Builder.hops(): hopDistance not implemented " +
"for this name type");
}
return incomparable;
}
X500Name baseName = (X500Name)base;
X500Name testName = (X500Name)test;
X500Name commonName = baseName.commonAncestor(testName);
if (commonName == null) {
if (debug != null) {
debug.println("Builder.hops(): Names are in different " +
"namespaces");
}
return incomparable;
} else {
int commonDistance = commonName.subtreeDepth();
int baseDistance = baseName.subtreeDepth();
int testDistance = testName.subtreeDepth();
return (baseDistance + testDistance - (2 * commonDistance));
}
}
/**
* Determine how close a given certificate gets you toward
* a given target.
*
* @param constraints Current NameConstraints; if null,
* then caller must verify NameConstraints
* independently, realizing that this certificate
* may not actually lead to the target at all.
* @param cert Candidate certificate for chain
* @param target GeneralNameInterface name of target
* @return distance from this certificate to target:
* <ul>
* <li>-1 means certificate could be CA for target, but
* there are no NameConstraints limiting how close
* <li> 0 means certificate subject or subjectAltName
* matches target
* <li> 1 means certificate is permitted to be CA for
* target.
* <li> 2 means certificate is permitted to be CA for
* parent of target.
* <li>>0 in general, means certificate is permitted
* to be a CA for this distance higher in the naming
* hierarchy than the target, plus 1.
* </ul>
* <p>Note that the subject and/or subjectAltName of the
* candidate cert does not have to be an ancestor of the
* target in order to be a CA that can issue a certificate to
* the target. In these cases, the target distance is calculated
* by inspecting the NameConstraints extension in the candidate
* certificate. For example, suppose the target is an X.500 DN with
* a value of "CN=mullan,OU=ireland,O=sun,C=us" and the
* NameConstraints extension in the candidate certificate
* includes a permitted component of "O=sun,C=us", which implies
* that the candidate certificate is allowed to issue certs in
* the "O=sun,C=us" namespace. The target distance is 3
* ((distance of permitted NC from target) + 1).
* The (+1) is added to distinguish the result from the case
* which returns (0).
* @throws IOException if certificate does not get closer
*/
static int targetDistance(NameConstraintsExtension constraints,
X509Certificate cert, GeneralNameInterface target)
throws IOException {
/* ensure that certificate satisfies existing name constraints */
if (constraints != null && !constraints.verify(cert)) {
throw new IOException("certificate does not satisfy existing name "
+ "constraints");
}
X509CertImpl certImpl;
try {
certImpl = X509CertImpl.toImpl(cert);
} catch (CertificateException e) {
throw (IOException)new IOException("Invalid certificate").initCause(e);
}
/* see if certificate subject matches target */
X500Name subject = X500Name.asX500Name(certImpl.getSubjectX500Principal());
if (subject.equals(target)) {
/* match! */
return 0;
}
SubjectAlternativeNameExtension altNameExt =
certImpl.getSubjectAlternativeNameExtension();
if (altNameExt != null) {
GeneralNames altNames =
(GeneralNames)altNameExt.get(altNameExt.SUBJECT_NAME);
/* see if any alternative name matches target */
if (altNames != null) {
for (int j = 0, n = altNames.size(); j < n; j++) {
GeneralNameInterface altName = altNames.get(j).getName();
if (altName.equals(target)) {
return 0;
}
}
}
}
/* no exact match; see if certificate can get us to target */
/* first, get NameConstraints out of certificate */
NameConstraintsExtension ncExt = certImpl.getNameConstraintsExtension();
if (ncExt == null) {
return -1;
}
/* merge certificate's NameConstraints with current NameConstraints */
if (constraints != null) {
constraints.merge(ncExt);
} else {
// Make sure we do a clone here, because we're probably
// going to modify this object later and we don't want to
// be sharing it with a Certificate object!
constraints = (NameConstraintsExtension) ncExt.clone();
}
if (debug != null) {
debug.println("Builder.targetDistance() merged constraints: "
+ String.valueOf(constraints));
}
/* reduce permitted by excluded */
GeneralSubtrees permitted = (GeneralSubtrees)
constraints.get(constraints.PERMITTED_SUBTREES);
GeneralSubtrees excluded = (GeneralSubtrees)
constraints.get(constraints.EXCLUDED_SUBTREES);
if (permitted != null) {
permitted.reduce(excluded);
}
if (debug != null) {
debug.println("Builder.targetDistance() reduced constraints: "
+ permitted);
}
/* see if new merged constraints allow target */
if (!constraints.verify(target)) {
throw new IOException("New certificate not allowed to sign "
+ "certificate for target");
}
/* find distance to target, if any, in permitted */
if (permitted == null) {
/* certificate is unconstrained; could sign for anything */
return -1;
}
for (int i = 0, n = permitted.size(); i < n; i++) {
GeneralNameInterface perName = permitted.get(i).getName().getName();
int distance = distance(perName, target, -1);
if (distance >= 0) {
return (distance + 1);
}
}
/* no matching type in permitted; cert holder could certify target */
return -1;
}
/**
* This method can be used as an optimization to filter out
* certificates that do not have policies which are valid.
* It returns the set of policies (String OIDs) that should exist in
* the certificate policies extension of the certificate that is
* needed by the builder. The logic applied is as follows:
* <p>
* 1) If some initial policies have been set *and* policy mappings are
* inhibited, then acceptable certificates are those that include
* the ANY_POLICY OID or with policies that intersect with the
* initial policies.
* 2) If no initial policies have been set *or* policy mappings are
* not inhibited then we don't have much to work with. All we know is
* that a certificate must have *some* policy because if it didn't
* have any policy then the policy tree would become null (and validation
* would fail).
*
* @return the Set of policies any of which must exist in a
* cert's certificate policies extension in order for a cert to be selected.
*/
Set<String> getMatchingPolicies() {
if (matchingPolicies != null) {
Set<String> initialPolicies = buildParams.getInitialPolicies();
if ((!initialPolicies.isEmpty()) &&
(!initialPolicies.contains(PolicyChecker.ANY_POLICY)) &&
(buildParams.isPolicyMappingInhibited()))
{
initialPolicies.add(PolicyChecker.ANY_POLICY);
matchingPolicies = initialPolicies;
} else {
// we just return an empty set to make sure that there is
// at least a certificate policies extension in the cert
matchingPolicies = Collections.<String>emptySet();
}
}
return matchingPolicies;
}
/**
* Search the specified CertStores and add all certificates matching
* selector to resultCerts. Self-signed certs are not useful here
* and therefore ignored.
*
* If the targetCert criterion of the selector is set, only that cert
* is examined and the CertStores are not searched.
*
* If checkAll is true, all CertStores are searched for matching certs.
* If false, the method returns as soon as the first CertStore returns
* a matching cert(s).
*
* Returns true iff resultCerts changed (a cert was added to the collection)
*/
boolean addMatchingCerts(X509CertSelector selector,
Collection<CertStore> certStores,
Collection<X509Certificate> resultCerts, boolean checkAll) {
X509Certificate targetCert = selector.getCertificate();
if (targetCert != null) {
// no need to search CertStores
if (selector.match(targetCert) && !X509CertImpl.isSelfSigned
(targetCert, buildParams.getSigProvider())) {
if (debug != null) {
debug.println("Builder.addMatchingCerts: adding target cert");
}
return resultCerts.add(targetCert);
}
return false;
}
boolean add = false;
for (CertStore store : certStores) {
try {
Collection<? extends Certificate> certs =
store.getCertificates(selector);
for (Certificate cert : certs) {
if (!X509CertImpl.isSelfSigned
((X509Certificate)cert, buildParams.getSigProvider())) {
if (resultCerts.add((X509Certificate)cert)) {
add = true;
}
}
}
if (!checkAll && add) {
return true;
}
} catch (CertStoreException cse) {
// if getCertificates throws a CertStoreException, we ignore
// it and move on to the next CertStore
if (debug != null) {
debug.println("Builder.addMatchingCerts, non-fatal " +
"exception retrieving certs: " + cse);
cse.printStackTrace();
}
}
}
return add;
}
/**
* Returns true if CertStore is local. Currently, returns true if
* type is Collection or if it has been initialized with
* CollectionCertStoreParameters. A new API method should be added
* to CertStore that returns local or remote.
*/
static boolean isLocalCertStore(CertStore certStore) {
return (certStore.getType().equals("Collection") ||
certStore.getCertStoreParameters() instanceof
CollectionCertStoreParameters);
}
}