support encryption subkeys with future signature dates

OpenKeychain/src/main/java/org/sufficientlysecure/keychain/KeychainDatabase.java

@@ -48,7 +48,7 @@ import timber.log.Timber;
  */
 public class KeychainDatabase {
     private static final String DATABASE_NAME = "openkeychain.db";
-    private static final int DATABASE_VERSION = 31;
+    private static final int DATABASE_VERSION = 32;
     private final SupportSQLiteOpenHelper supportSQLiteOpenHelper;
 
     private static KeychainDatabase sInstance;
@@ -348,6 +348,20 @@ public class KeychainDatabase {
 
             case 30:
                 // ignore. this case only came up in an unreleased beta.
+
+            case 31:
+                addSubkeyValidFromField(db);
+        }
+    }
+
+    private void addSubkeyValidFromField(SupportSQLiteDatabase db) {
+        try {
+            db.beginTransaction();
+            db.execSQL("ALTER TABLE keys ADD COLUMN validFrom INTEGER NOT NULL DEFAULT 0;");
+            db.execSQL("UPDATE keys SET validFrom = creation");
+            db.setTransactionSuccessful();
+        } finally {
+            db.endTransaction();
         }
     }
 

OpenKeychain/src/main/java/org/sufficientlysecure/keychain/daos/KeyRepository.java

@@ -313,6 +313,11 @@ public class KeyRepository extends AbstractDao {
         return mapSingleRowOrThrow(query, SubKey.FACTORY.selectEffectiveAuthKeyIdByMasterKeyIdMapper());
     }
 
+    public List<Long> getPublicEncryptionIds(long masterKeyId) {
+        SqlDelightQuery query = SubKey.FACTORY.selectEffectiveEncryptionKeyIdsByMasterKeyId(masterKeyId);
+        return mapAllRows(query, SubKey.FACTORY.selectEffectiveEncryptionKeyIdsByMasterKeyIdMapper());
+    }
+
     public static class NotFoundException extends Exception {
         public NotFoundException() {
         }

OpenKeychain/src/main/java/org/sufficientlysecure/keychain/daos/KeyWritableRepository.java

@@ -225,6 +225,7 @@ public class KeyWritableRepository extends KeyRepository {
                     }
 
                     Date creation = key.getCreationTime();
+                    Date bindingSignatureTime = key.getBindingSignatureTime();
                     Date expiry = key.getExpiryTime();
                     if (expiry != null) {
                         if (key.isExpired()) {
@@ -240,7 +241,7 @@ public class KeyWritableRepository extends KeyRepository {
 
                     SubKey subKey = SubKey.create(masterKeyId, rank, key.getKeyId(),
                             key.getBitStrength(), key.getCurveOid(), key.getAlgorithm(), key.getFingerprint(),
-                            c, s, e, a, key.isRevoked(), SecretKeyType.UNAVAILABLE, key.isSecure(), creation, expiry);
+                            c, s, e, a, key.isRevoked(), SecretKeyType.UNAVAILABLE, key.isSecure(), creation, expiry, bindingSignatureTime);
                     operations.add(DatabaseBatchInteractor.createInsertSubKey(subKey));
 
                     ++rank;

OpenKeychain/src/main/java/org/sufficientlysecure/keychain/model/SubKey.java

@@ -31,11 +31,13 @@ public abstract class SubKey implements KeysModel {
 
     public static SubKey create(long masterKeyId, long rank, long keyId, Integer keySize, String keyCurveOid,
             int algorithm, byte[] fingerprint, boolean canCertify, boolean canSign, boolean canEncrypt, boolean canAuth,
-            boolean isRevoked, SecretKeyType hasSecret, boolean isSecure, Date creation, Date expiry) {
+            boolean isRevoked, SecretKeyType hasSecret, boolean isSecure, Date creation, Date expiry,
+            Date validFrom) {
         long creationUnixTime = creation.getTime() / 1000;
         Long expiryUnixTime = expiry != null ? expiry.getTime() / 1000 : null;
+        long validFromTime = validFrom.getTime() / 1000;
         return new AutoValue_SubKey(masterKeyId, rank, keyId, keySize, keyCurveOid, algorithm, fingerprint, canCertify,
-                canSign, canEncrypt, canAuth, isRevoked, hasSecret, isSecure, creationUnixTime, expiryUnixTime);
+                canSign, canEncrypt, canAuth, isRevoked, hasSecret, isSecure, creationUnixTime, expiryUnixTime, validFromTime);
     }
 
     public static InsertKey createInsertStatement(SupportSQLiteDatabase db) {
@@ -53,7 +55,7 @@ public abstract class SubKey implements KeysModel {
     public void bindTo(InsertKey statement) {
         statement.bind(master_key_id(), rank(), key_id(), key_size(), key_curve_oid(), algorithm(), fingerprint(),
                 can_certify(), can_sign(), can_encrypt(), can_authenticate(), is_revoked(), has_secret(), is_secure(),
-                creation(), expiry());
+                creation(), expiry(), validFrom());
     }
 
     @AutoValue

OpenKeychain/src/main/java/org/sufficientlysecure/keychain/operations/results/OperationResult.java

@@ -455,7 +455,6 @@ public abstract class OperationResult implements Parcelable {
         MSG_KC_SUB_BAD_ERR(LogLevel.WARN, R.string.msg_kc_sub_bad_err),
         MSG_KC_SUB_BAD_LOCAL(LogLevel.WARN, R.string.msg_kc_sub_bad_local),
         MSG_KC_SUB_BAD_KEYID(LogLevel.WARN, R.string.msg_kc_sub_bad_keyid),
-        MSG_KC_SUB_BAD_TIME(LogLevel.WARN, R.string.msg_kc_sub_bad_time),
         MSG_KC_SUB_BAD_TIME_EARLY(LogLevel.WARN, R.string.msg_kc_sub_bad_time_early),
         MSG_KC_SUB_BAD_TYPE(LogLevel.WARN, R.string.msg_kc_sub_bad_type),
         MSG_KC_SUB_DUP (LogLevel.DEBUG, R.string.msg_kc_sub_dup),

OpenKeychain/src/main/java/org/sufficientlysecure/keychain/pgp/CanonicalizedPublicKey.java

@@ -134,11 +134,33 @@ public class CanonicalizedPublicKey extends UncachedPublicKey {
                 : PGPSignature.SUBKEY_REVOCATION).hasNext();
     }
 
-    public boolean isExpired () {
+    public boolean isExpired() {
         Date expiry = getExpiryTime();
         return expiry != null && expiry.before(new Date());
     }
 
+    private boolean hasFutureSigningDate() {
+        if (isMasterKey()) {
+            return false;
+        }
+
+        WrappedSignature subkeyBindingSignature = getSubkeyBindingSignature();
+        return subkeyBindingSignature.getCreationTime().after(new Date());
+    }
+
+    private WrappedSignature getSubkeyBindingSignature() {
+        Iterator subkeyBindingSignatures = mPublicKey.getSignaturesOfType(PGPSignature.SUBKEY_BINDING);
+        PGPSignature singleSubkeyBindingsignature = (PGPSignature) subkeyBindingSignatures.next();
+        if (subkeyBindingSignatures.hasNext()) {
+            throw new IllegalStateException();
+        }
+        return new WrappedSignature(singleSubkeyBindingsignature);
+    }
+
+    public Date getBindingSignatureTime() {
+        return isMasterKey() ? getCreationTime() : getSubkeyBindingSignature().getCreationTime();
+    }
+
     public boolean isSecure() {
         return PgpSecurityConstants.checkForSecurityProblems(this) == null;
     }
@@ -206,7 +228,7 @@ public class CanonicalizedPublicKey extends UncachedPublicKey {
 
     /** Returns whether this key is valid, ie not expired or revoked. */
     public boolean isValid() {
-        return !isRevoked() && !isExpired();
+        return !isRevoked() && !isExpired() && !hasFutureSigningDate();
     }
 
     // For use in key export only; returns the public key in a JCA compatible format.

OpenKeychain/src/main/java/org/sufficientlysecure/keychain/pgp/PgpSignEncryptOperation.java

@@ -32,7 +32,7 @@ import java.io.UnsupportedEncodingException;
 import java.security.SignatureException;
 import java.util.Collection;
 import java.util.Date;
-import java.util.Set;
+import java.util.List;
 import java.util.concurrent.atomic.AtomicBoolean;
 
 import android.content.Context;
@@ -651,7 +651,7 @@ public class PgpSignEncryptOperation extends BaseOperation<PgpSignEncryptInputPa
             PGPEncryptedDataGenerator cPk, long encryptMasterKeyId) {
         try {
             CanonicalizedPublicKeyRing keyRing = mKeyRepository.getCanonicalizedPublicKeyRing(encryptMasterKeyId);
-            Set<Long> encryptSubKeyIds = keyRing.getEncryptIds();
+            List<Long> encryptSubKeyIds = mKeyRepository.getPublicEncryptionIds(encryptMasterKeyId);
             for (Long subKeyId : encryptSubKeyIds) {
                 CanonicalizedPublicKey key = keyRing.getPublicKey(subKeyId);
                 cPk.addMethod(key.getPubKeyEncryptionGenerator(data.isHiddenRecipients()));

OpenKeychain/src/main/java/org/sufficientlysecure/keychain/pgp/UncachedKeyRing.java

@@ -912,13 +912,6 @@ public class UncachedKeyRing {
                     continue;
                 }
 
-                if (cert.getCreationTime().after(nowPlusOneDay)) {
-                    // Creation date in the future? No way!
-                    log.add(LogType.MSG_KC_SUB_BAD_TIME, indent);
-                    badCerts += 1;
-                    continue;
-                }
-
                 if (cert.getCreationTime().before(keyCreationTime)) {
                     // Signature is earlier than key creation time
                     log.add(LogType.MSG_KC_SUB_BAD_TIME_EARLY, indent);

OpenKeychain/src/main/sqldelight/org/sufficientlysecure/keychain/Keys.sq

@@ -18,6 +18,7 @@ CREATE TABLE IF NOT EXISTS keys (
     is_secure INTEGER AS Boolean NOT NULL,
     creation INTEGER NOT NULL,
     expiry INTEGER,
+    validFrom INTEGER NOT NULL,
     PRIMARY KEY(master_key_id, rank),
     FOREIGN KEY(master_key_id) REFERENCES
     keyrings_public(master_key_id) ON DELETE CASCADE
@@ -27,8 +28,8 @@ insertKey:
 INSERT INTO keys (
         master_key_id, rank, key_id, key_size, key_curve_oid, algorithm, fingerprint,
         can_certify, can_sign, can_encrypt, can_authenticate,
-        is_revoked, has_secret, is_secure, creation, expiry
+        is_revoked, has_secret, is_secure, creation, expiry, validFrom
-    ) VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?);
+    ) VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?);
 
 updateHasSecretByMasterKeyId:
 UPDATE keys
@@ -91,7 +92,7 @@ SELECT master_key_id
     WHERE key_id = ?;
 
 selectSubkeysByMasterKeyId:
-SELECT master_key_id, rank, key_id, key_size, key_curve_oid, algorithm, fingerprint, can_certify, can_sign, can_encrypt, can_authenticate, is_revoked, has_secret, is_secure, creation, expiry
+SELECT master_key_id, rank, key_id, key_size, key_curve_oid, algorithm, fingerprint, can_certify, can_sign, can_encrypt, can_authenticate, is_revoked, has_secret, is_secure, creation, expiry, validFrom
     FROM keys
     WHERE master_key_id = ?
     ORDER BY rank ASC;
@@ -106,6 +107,12 @@ SELECT fingerprint
     FROM keys
     WHERE key_id = ?;
 
+selectEffectiveEncryptionKeyIdsByMasterKeyId:
+SELECT key_id
+    FROM keys
+    WHERE is_revoked = 0 AND is_secure = 1 AND ( expiry IS NULL OR expiry >= strftime('%s', 'now') ) AND validFrom <= strftime('%s', 'now')
+        AND can_encrypt = 1 AND master_key_id = ?;
+
 selectEffectiveSignKeyIdByMasterKeyId:
 SELECT key_id
     FROM keys