Prevent IAE when encountering non-UTF8 User-ID on a public key

Fixes #392

pgpainless-core/src/main/java/org/pgpainless/key/info/KeyRingInfo.java

@@ -42,6 +42,7 @@ import org.pgpainless.exception.KeyException;
 import org.pgpainless.key.OpenPgpFingerprint;
 import org.pgpainless.key.SubkeyIdentifier;
 import org.pgpainless.key.util.KeyIdUtil;
+import org.pgpainless.key.util.KeyRingUtils;
 import org.pgpainless.key.util.RevocationAttributes;
 import org.pgpainless.policy.Policy;
 import org.pgpainless.signature.SignatureUtils;
@@ -382,8 +383,7 @@ public class KeyRingInfo {
      */
     @Nonnull
     public List<String> getUserIds() {
-        Iterator<String> iterator = getPublicKey().getUserIDs();
+        return KeyRingUtils.getUserIdsIgnoringInvalidUTF8(keys.getPublicKey());
-        return iteratorToList(iterator);
     }
 
     /**
@@ -1284,8 +1284,8 @@ public class KeyRingInfo {
             subkeyRevocations = new HashMap<>();
             subkeyBindings = new HashMap<>();
 
-            for (Iterator<String> it = keyRing.getPublicKey().getUserIDs(); it.hasNext(); ) {
+            List<String> userIds = KeyRingUtils.getUserIdsIgnoringInvalidUTF8(keyRing.getPublicKey());
-                String userId = it.next();
+            for (String userId : userIds) {
                 PGPSignature revocation = SignaturePicker.pickCurrentUserIdRevocationSignature(keyRing, userId, policy, referenceDate);
                 if (revocation != null) {
                     userIdRevocations.put(userId, revocation);

pgpainless-core/src/main/java/org/pgpainless/key/util/KeyRingUtils.java

@@ -25,10 +25,13 @@ import org.bouncycastle.openpgp.PGPSecretKeyRing;
 import org.bouncycastle.openpgp.PGPSecretKeyRingCollection;
 import org.bouncycastle.openpgp.PGPSignature;
 import org.bouncycastle.openpgp.PGPUserAttributeSubpacketVector;
+import org.bouncycastle.util.Strings;
 import org.pgpainless.PGPainless;
 import org.pgpainless.implementation.ImplementationFactory;
 import org.pgpainless.key.protection.SecretKeyRingProtector;
 import org.pgpainless.key.protection.UnlockSecretKey;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 public final class KeyRingUtils {
 
@@ -36,6 +39,8 @@ public final class KeyRingUtils {
 
     }
 
+    private static final Logger LOGGER = LoggerFactory.getLogger(KeyRingUtils.class);
+
     /**
      * Return the primary {@link PGPSecretKey} from the provided {@link PGPSecretKeyRing}.
      * If it has no primary secret key, throw a {@link NoSuchElementException}.
@@ -485,4 +490,29 @@ public final class KeyRingUtils {
         // Parse the key back into an object
         return new PGPSecretKeyRing(encoded.toByteArray(), ImplementationFactory.getInstance().getKeyFingerprintCalculator());
     }
+
+    /**
+     * Strip all user-ids, user-attributes and signatures from the given public key.
+     *
+     * @param bloatedKey public key
+     * @return stripped public key
+     * @throws PGPException if the packet is faulty or the required calculations fail
+     */
+    public static PGPPublicKey getStrippedDownPublicKey(PGPPublicKey bloatedKey) throws PGPException {
+        return new PGPPublicKey(bloatedKey.getPublicKeyPacket(), ImplementationFactory.getInstance().getKeyFingerprintCalculator());
+    }
+
+    public static List<String> getUserIdsIgnoringInvalidUTF8(PGPPublicKey key) {
+        List<String> userIds = new ArrayList<>();
+        Iterator<byte[]> it = key.getRawUserIDs();
+        while (it.hasNext()) {
+            byte[] rawUserId = it.next();
+            try {
+                userIds.add(Strings.fromUTF8ByteArray(rawUserId));
+            } catch (IllegalArgumentException e) {
+                LOGGER.warn("Invalid UTF-8 user-ID encountered: " + new String(rawUserId));
+            }
+        }
+        return userIds;
+    }
 }

pgpainless-core/src/main/java/org/pgpainless/signature/consumer/CertificateValidator.java

@@ -23,6 +23,7 @@ import org.bouncycastle.openpgp.PGPSignature;
 import org.pgpainless.algorithm.KeyFlag;
 import org.pgpainless.algorithm.SignatureType;
 import org.pgpainless.exception.SignatureValidationException;
+import org.pgpainless.key.util.KeyRingUtils;
 import org.pgpainless.policy.Policy;
 import org.pgpainless.signature.SignatureUtils;
 import org.pgpainless.signature.subpackets.SignatureSubpacketsUtil;
@@ -113,11 +114,10 @@ public final class CertificateValidator {
         }
 
         // User-ID signatures (certifications, revocations)
-        Iterator<String> userIds = primaryKey.getUserIDs();
+        List<String> userIds = KeyRingUtils.getUserIdsIgnoringInvalidUTF8(primaryKey);
         Map<String, List<PGPSignature>> userIdSignatures = new ConcurrentHashMap<>();
-        while (userIds.hasNext()) {
+        for (String userId : userIds) {
             List<PGPSignature> signaturesOnUserId = new ArrayList<>();
-            String userId = userIds.next();
             Iterator<PGPSignature> userIdSigs = primaryKey.getSignaturesForID(userId);
             while (userIdSigs.hasNext()) {
                 PGPSignature userIdSig = userIdSigs.next();

pgpainless-core/src/main/java/org/pgpainless/util/ArmorUtils.java

@@ -32,6 +32,7 @@ import org.bouncycastle.util.io.Streams;
 import org.pgpainless.algorithm.HashAlgorithm;
 import org.pgpainless.decryption_verification.OpenPgpInputStream;
 import org.pgpainless.key.OpenPgpFingerprint;
+import org.pgpainless.key.util.KeyRingUtils;
 
 /**
  * Utility class for dealing with ASCII armored OpenPGP data.
@@ -388,13 +389,12 @@ public final class ArmorUtils {
         // Quickly determine the primary user-id + number of total user-ids
         // NOTE: THIS METHOD DOES NOT CRYPTOGRAPHICALLY VERIFY THE SIGNATURES
         // DO NOT RELY ON IT!
-        Iterator<String> userIds = publicKey.getUserIDs();
+        List<String> userIds = KeyRingUtils.getUserIdsIgnoringInvalidUTF8(publicKey);
         int countIdentities = 0;
         String first = null;
         String primary = null;
-        while (userIds.hasNext()) {
+        for (String userId : userIds) {
             countIdentities++;
-            String userId = userIds.next();
             // remember the first user-id
             if (first == null) {
                 first = userId;

pgpainless-core/src/main/java/org/pgpainless/util/selection/keyring/impl/ExactUserId.java

@@ -4,10 +4,11 @@
 
 package org.pgpainless.util.selection.keyring.impl;
 
-import java.util.Iterator;
+import java.util.List;
 
 import org.bouncycastle.openpgp.PGPPublicKeyRing;
 import org.bouncycastle.openpgp.PGPSecretKeyRing;
+import org.pgpainless.key.util.KeyRingUtils;
 import org.pgpainless.util.selection.keyring.PublicKeyRingSelectionStrategy;
 import org.pgpainless.util.selection.keyring.SecretKeyRingSelectionStrategy;
 
@@ -29,9 +30,9 @@ public final class ExactUserId {
 
         @Override
         public boolean accept(String identifier, PGPPublicKeyRing keyRing) {
-            Iterator<String> userIds = keyRing.getPublicKey().getUserIDs();
+            List<String> userIds = KeyRingUtils.getUserIdsIgnoringInvalidUTF8(keyRing.getPublicKey());
-            while (userIds.hasNext()) {
+            for (String userId : userIds) {
-                if (userIds.next().equals(identifier)) return true;
+                if (userId.equals(identifier)) return true;
             }
             return false;
         }
@@ -45,9 +46,9 @@ public final class ExactUserId {
 
         @Override
         public boolean accept(String identifier, PGPSecretKeyRing keyRing) {
-            Iterator<String> userIds = keyRing.getPublicKey().getUserIDs();
+            List<String> userIds = KeyRingUtils.getUserIdsIgnoringInvalidUTF8(keyRing.getPublicKey());
-            while (userIds.hasNext()) {
+            for (String userId : userIds) {
-                if (userIds.next().equals(identifier)) return true;
+                if (userId.equals(identifier)) return true;
             }
             return false;
         }