[ELY-1446] Add utility methods for converting an unordered array of certificates into an ordered X.509 certificate chain and for creating an X.509 certificate chain from a map of certificates

src/main/java/org/wildfly/security/_private/ElytronMessages.java

@@ -1918,6 +1918,18 @@ public interface ElytronMessages extends BasicLogger {
     @Message(id = 10024, value = "Invalid X.509 certificate extension string value")
     IllegalArgumentException invalidCertificateExtensionStringValue();
 
+    @Message(id = 10025, value = "Non-X.509 certificate found in certificate array")
+    IllegalArgumentException nonX509CertificateInCertificateArray();
+
+    @Message(id = 10026, value = "Starting public key not found in certificate array")
+    IllegalArgumentException startingPublicKeyNotFoundInCertificateArray();
+
+    @Message(id = 10027, value = "Incomplete certificate array")
+    IllegalArgumentException incompleteCertificateArray();
+
+    @Message(id = 10028, value = "Unable to create X.509 certificate chain from map of certificates")
+    IllegalArgumentException unableToCreateCertificateChainFromCertificateMap();
+
     /* Audit Exceptions */
 
     // 11000 - Unused in any Final release

src/main/java/org/wildfly/security/x500/X500.java

@@ -18,8 +18,19 @@
 
 package org.wildfly.security.x500;
 
+import static org.wildfly.security._private.ElytronMessages.log;
+
+import java.security.Principal;
+import java.security.PublicKey;
+import java.security.cert.Certificate;
 import java.security.cert.X509Certificate;
+import java.util.ArrayList;
 import java.util.Arrays;
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.HashSet;
+
+import org.wildfly.common.Assert;
 
 /**
  * Useful X500 constants and utilities.
@@ -137,4 +148,113 @@ public static X509Certificate[] asX509CertificateArray(Object[] certificates) th
             return Arrays.copyOf(certificates, certificates.length, X509Certificate[].class);
         }
     }
+
+    /**
+     * Convert an unordered array of certificates into an ordered X.509 certificate chain.
+     *
+     * @param firstPublicKey the public key that should be in the first certificate in the ordered X.509 certificate
+     *                       chain (may not be {@code null})
+     * @param certificates the unordered array of certificates (may not be {@code null})
+     * @return the ordered X.509 certificate chain, as an array
+     * @throws IllegalArgumentException if the given unordered array of certificates cannot be converted into an ordered X.509 certificate chain
+     */
+    public static X509Certificate[] asOrderedX509CertificateChain(PublicKey firstPublicKey, Certificate[] certificates) throws IllegalArgumentException {
+        Assert.checkNotNullParam("firstPublicKey", firstPublicKey);
+        Assert.checkNotNullParam("certificates", certificates);
+        X509Certificate[] x509Certificates;
+        try {
+            x509Certificates = asX509CertificateArray(certificates);
+        } catch (ArrayStoreException e) {
+            throw log.nonX509CertificateInCertificateArray();
+        }
+        boolean foundFirstCertificate = false;
+        for (int i = 0; i < x509Certificates.length; i++) {
+            if (x509Certificates[i].getPublicKey().equals(firstPublicKey)) {
+                foundFirstCertificate = true;
+                swapCertificates(x509Certificates, 0, i);
+                break;
+            }
+        }
+        if (! foundFirstCertificate) {
+            throw log.startingPublicKeyNotFoundInCertificateArray();
+        }
+        X509Certificate currentCertificate = x509Certificates[0];
+        for (int i = 1; i < x509Certificates.length - 1; i++) {
+            boolean issuerCertificateFound = false;
+            for (int j = i; j < x509Certificates.length; j++) {
+                if (issuedBy(currentCertificate, x509Certificates[j])) {
+                    swapCertificates(x509Certificates, i, j);
+                    issuerCertificateFound = true;
+                    currentCertificate = x509Certificates[i];
+                    break;
+                }
+            }
+            if (! issuerCertificateFound) {
+                throw log.incompleteCertificateArray();
+            }
+        }
+        return x509Certificates;
+    }
+
+    /**
+     * Create an X.509 certificate chain given the first certificate that should be in the chain and a map of certificates.
+     *
+     * @param firstCertificate the certificate that should be first in the newly created X.509 certificate chain
+     * @param certificatesMap a map of distinguished names to certificates to use to create the X.509 certificate chain
+     * @return the newly created X.509 certificate chain, as an array
+     * @throws IllegalArgumentException if the X.509 certificate chain could not be created
+     */
+    public static X509Certificate[] createX509CertificateChain(final X509Certificate firstCertificate,
+                                                               final HashMap<Principal, HashSet<X509Certificate>> certificatesMap) throws IllegalArgumentException {
+        Assert.checkNotNullParam("firstCertificate", firstCertificate);
+        Assert.checkNotNullParam("certificatesMap", certificatesMap);
+        final ArrayList<X509Certificate> certificateChain = new ArrayList<>();
+        if (createX509CertificateChain(firstCertificate, certificateChain, certificatesMap)) {
+            Collections.reverse(certificateChain);
+            return certificateChain.toArray(new X509Certificate[certificateChain.size()]);
+        }
+        throw log.unableToCreateCertificateChainFromCertificateMap();
+    }
+
+    private static void swapCertificates(Certificate[] certificates, int i, int j) {
+        Certificate tempCertificate = certificates[i];
+        certificates[i] = certificates[j];
+        certificates[j] = tempCertificate;
+    }
+
+    private static boolean issuedBy(final X509Certificate certificate, X509Certificate issuer) {
+        if (issuer.getSubjectDN().equals(certificate.getIssuerDN())) {
+            try {
+                certificate.verify(issuer.getPublicKey());
+                return true;
+            } catch (Exception e) {
+                return false;
+            }
+        }
+        return false;
+    }
+
+    private static boolean createX509CertificateChain(final X509Certificate firstCertificate, final ArrayList<X509Certificate> certificateChain,
+                                                      final HashMap<Principal, HashSet<X509Certificate>> certificatesMap) {
+        if (issuedBy(firstCertificate, firstCertificate)) {
+            // self-signed
+            certificateChain.add(firstCertificate);
+            return true;
+        }
+        final HashSet<X509Certificate> issuerCertificates = certificatesMap.get(firstCertificate.getIssuerDN());
+        if (issuerCertificates == null || issuerCertificates.isEmpty()) {
+            return false;
+        }
+        for (X509Certificate issuerCertificate : issuerCertificates) {
+            if (issuedBy(firstCertificate, issuerCertificate)) {
+                // recurse
+                if (createX509CertificateChain(issuerCertificate, certificateChain, certificatesMap)) {
+                    certificateChain.add(firstCertificate);
+                    return true;
+                }
+            }
+        }
+        return false;
+    }
+
 }

src/test/java/org/wildfly/security/x500/X500Test.java

@@ -0,0 +1,159 @@
+/*
+ * JBoss, Home of Professional Open Source.
+ * Copyright 2017 Red Hat, Inc., and individual contributors
+ * as indicated by the @author tags.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS,
+ *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ */
+
+package org.wildfly.security.x500;
+
+import static org.junit.Assert.*;
+
+import java.security.KeyPair;
+import java.security.KeyPairGenerator;
+import java.security.NoSuchAlgorithmException;
+import java.security.Principal;
+import java.security.cert.X509Certificate;
+import java.util.Arrays;
+import java.util.HashMap;
+import java.util.HashSet;
+
+import javax.security.auth.x500.X500Principal;
+
+import org.junit.Test;
+import org.wildfly.security.asn1.ASN1Encodable;
+import org.wildfly.security.x500.cert.X509CertificateBuilder;
+
+/**
+ * Tests for X500 utilities.
+ *
+ * @author <a href="mailto:fjuma@redhat.com">Farah Juma</a>
+ */
+public class X500Test {
+
+    private static X509Certificate[] populateCertificateChain() throws Exception {
+        KeyPairGenerator keyPairGenerator;
+        try {
+            keyPairGenerator = KeyPairGenerator.getInstance("RSA");
+        } catch (NoSuchAlgorithmException e) {
+            throw new Error(e);
+        }
+        final KeyPair[] keyPairs = new KeyPair[5];
+        for (int i = 0; i < keyPairs.length; i++) {
+            keyPairs[i] = keyPairGenerator.generateKeyPair();
+        }
+        final X509Certificate[] orderedCertificates = new X509Certificate[5];
+        for (int i = 0; i < orderedCertificates.length; i++) {
+            X509CertificateBuilder builder = new X509CertificateBuilder();
+            X500PrincipalBuilder principalBuilder = new X500PrincipalBuilder();
+            principalBuilder.addItem(X500AttributeTypeAndValue.create(X500.OID_AT_COMMON_NAME,
+                    ASN1Encodable.ofUtf8String("bob" + i)));
+            X500Principal dn = principalBuilder.build();
+            builder.setSubjectDn(dn);
+            if (i == orderedCertificates.length - 1) {
+                // self-signed
+                builder.setIssuerDn(dn);
+                builder.setSigningKey(keyPairs[i].getPrivate());
+            } else {
+                principalBuilder = new X500PrincipalBuilder();
+                principalBuilder.addItem(X500AttributeTypeAndValue.create(X500.OID_AT_COMMON_NAME,
+                        ASN1Encodable.ofUtf8String("bob" + (i + 1))));
+                X500Principal issuerDn = principalBuilder.build();
+                builder.setIssuerDn(issuerDn);
+                builder.setSigningKey(keyPairs[i + 1].getPrivate());
+            }
+            builder.setSignatureAlgorithmName("SHA256withRSA");
+            builder.setPublicKey(keyPairs[i].getPublic());
+            orderedCertificates[i] = builder.build();
+        }
+        return orderedCertificates;
+    }
+
+    @Test
+    public void testAsOrderedX509CertificateChain() throws Exception {
+        final X509Certificate[] orderedCertificates = populateCertificateChain();
+
+        X509Certificate[] unorderedCertificates = new X509Certificate[1];
+        unorderedCertificates[0] = orderedCertificates[4];
+        assertArrayEquals(new X509Certificate[] { orderedCertificates[4] }, X500.asOrderedX509CertificateChain(orderedCertificates[4].getPublicKey(), unorderedCertificates));
+
+        unorderedCertificates = new X509Certificate[5];
+        unorderedCertificates[0] = orderedCertificates[3];
+        unorderedCertificates[1] = orderedCertificates[0];
+        unorderedCertificates[2] = orderedCertificates[4];
+        unorderedCertificates[3] = orderedCertificates[1];
+        unorderedCertificates[4] = orderedCertificates[2];
+        assertArrayEquals(orderedCertificates, X500.asOrderedX509CertificateChain(orderedCertificates[0].getPublicKey(), unorderedCertificates));
+    }
+
+    @Test
+    public void testAsOrderedX509CertificateChainInvalidValues() throws Exception {
+        final X509Certificate[] orderedCertificates = populateCertificateChain();
+        try {
+            // without starting public key
+            X500.asOrderedX509CertificateChain(orderedCertificates[0].getPublicKey(), new X509Certificate[] { orderedCertificates[3], orderedCertificates[1], orderedCertificates[2] });
+            fail("Expected IllegalArgumentException not thrown");
+        } catch (IllegalArgumentException expected) {
+        }
+
+        try {
+            // incomplete array
+            X500.asOrderedX509CertificateChain(orderedCertificates[0].getPublicKey(), new X509Certificate[] { orderedCertificates[4], orderedCertificates[0], orderedCertificates[3], orderedCertificates[1] });
+            fail("Expected IllegalArgumentException not thrown");
+        } catch (IllegalArgumentException expected) {
+        }
+    }
+
+    @Test
+    public void testCreateX509CertificateChain() throws Exception {
+        final X509Certificate[] orderedCertificates = populateCertificateChain();
+        HashMap<Principal, HashSet<X509Certificate>> certificatesMap = new HashMap<>();
+
+        certificatesMap = new HashMap<>();
+        certificatesMap.put(orderedCertificates[4].getSubjectDN(), new HashSet<> (Arrays.asList(orderedCertificates[4])));
+        assertArrayEquals(new X509Certificate[] { orderedCertificates[4] }, X500.createX509CertificateChain(orderedCertificates[4], certificatesMap));
+
+        certificatesMap = new HashMap<>();
+        for (int i = 0; i < orderedCertificates.length; i++) {
+            certificatesMap.put(orderedCertificates[i].getSubjectDN(), new HashSet<> (Arrays.asList(orderedCertificates[i])));
+        }
+        assertArrayEquals(orderedCertificates, X500.createX509CertificateChain(orderedCertificates[0], certificatesMap));
+    }
+
+    @Test
+    public void testCreateX509CertificateChainInvalidValues() throws Exception {
+        final X509Certificate[] orderedCertificates = populateCertificateChain();
+        HashMap<Principal, HashSet<X509Certificate>> certificatesMap = new HashMap<>();
+
+        // incomplete map
+        for (int i = 0; i < orderedCertificates.length; i+=2) {
+            certificatesMap.put(orderedCertificates[i].getSubjectDN(), new HashSet<> (Arrays.asList(orderedCertificates[i])));
+        }
+        try {
+            X500.createX509CertificateChain(orderedCertificates[0], certificatesMap);
+            fail("Expected IllegalArgumentException not thrown");
+        } catch (IllegalArgumentException expected) {
+        }
+
+        // invalid starting certificate
+        for (int i = 2; i < orderedCertificates.length; i++) {
+            certificatesMap.put(orderedCertificates[i].getSubjectDN(), new HashSet<> (Arrays.asList(orderedCertificates[i])));
+        }
+        try {
+            X500.createX509CertificateChain(orderedCertificates[0], certificatesMap);
+            fail("Expected IllegalArgumentException not thrown");
+        } catch (IllegalArgumentException expected) {
+        }
+    }
+}