Add delete sync capability

integration-tests/src/main/java/org/signal/integration/TestUser.java

@@ -126,7 +126,7 @@ public class TestUser {
   }
 
   public AccountAttributes accountAttributes() {
-    return new AccountAttributes(true, registrationId, pniRegistrationId, "".getBytes(StandardCharsets.UTF_8), "", true, new Device.DeviceCapabilities(false, false, false))
+    return new AccountAttributes(true, registrationId, pniRegistrationId, "".getBytes(StandardCharsets.UTF_8), "", true, new Device.DeviceCapabilities(false, false, false, false))
         .withUnidentifiedAccessKey(unidentifiedAccessKey)
         .withRecoveryPassword(registrationPassword);
   }

service/src/main/java/org/whispersystems/textsecuregcm/controllers/DeviceController.java

@@ -232,6 +232,8 @@ public class DeviceController {
 
     if (capabilities == null) {
       throw new WebApplicationException(Response.status(422, "Missing device capabilities").build());
+    } else if (isCapabilityDowngrade(account, capabilities)) {
+      throw new WebApplicationException(Response.status(409).build());
     }
 
     final String signalAgent;
@@ -387,6 +389,10 @@ public class DeviceController {
     return Optional.of(aci);
   }
 
+  private static boolean isCapabilityDowngrade(Account account, DeviceCapabilities capabilities) {
+    return account.isDeleteSyncSupported() && !capabilities.deleteSync();
+  }
+
   private static String getUsedTokenKey(final String token) {
     return "usedToken::" + token;
   }

service/src/main/java/org/whispersystems/textsecuregcm/controllers/ProfileController.java

@@ -447,7 +447,7 @@ public class ProfileController {
     return new BaseProfileResponse(account.getIdentityKey(IdentityType.ACI),
         account.getUnidentifiedAccessKey().map(UnidentifiedAccessChecksum::generateFor).orElse(null),
         account.isUnrestrictedUnidentifiedAccess(),
-        new UserCapabilities(),
+        UserCapabilities.createForAccount(account),
         profileBadgeConverter.convert(
             getAcceptableLanguagesForRequest(containerRequestContext),
             account.getBadges(),
@@ -459,7 +459,7 @@ public class ProfileController {
     return new BaseProfileResponse(account.getIdentityKey(IdentityType.PNI),
         null,
         false,
-        new UserCapabilities(),
+        UserCapabilities.createForAccount(account),
         Collections.emptyList(),
         new PniServiceIdentifier(account.getPhoneNumberIdentifier()));
   }

service/src/main/java/org/whispersystems/textsecuregcm/entities/UserCapabilities.java

@@ -5,11 +5,14 @@
 
 package org.whispersystems.textsecuregcm.entities;
 
+import org.whispersystems.textsecuregcm.storage.Account;
+
 public record UserCapabilities(
     // TODO: Remove the paymentActivation capability entirely sometime soon after 2024-06-30
-    boolean paymentActivation) {
+    boolean paymentActivation,
+    boolean deleteSync) {
 
-  public UserCapabilities() {
+  public static UserCapabilities createForAccount(final Account account) {
-    this(true);
+    return new UserCapabilities(true, account.isDeleteSyncSupported());
   }
 }

service/src/main/java/org/whispersystems/textsecuregcm/grpc/DevicesGrpcService.java

@@ -201,7 +201,8 @@ public class DevicesGrpcService extends ReactorDevicesGrpc.DevicesImplBase {
                 d -> d.setCapabilities(new Device.DeviceCapabilities(
                     request.getStorage(),
                     request.getTransfer(),
-                    request.getPaymentActivation())))))
+                    request.getPaymentActivation(),
+                    request.getDeleteSync())))))
         .thenReturn(SetCapabilitiesResponse.newBuilder().build());
   }
 }

service/src/main/java/org/whispersystems/textsecuregcm/grpc/ProfileGrpcHelper.java

@@ -83,6 +83,7 @@ public class ProfileGrpcHelper {
   static UserCapabilities buildUserCapabilities(final org.whispersystems.textsecuregcm.entities.UserCapabilities capabilities) {
     return UserCapabilities.newBuilder()
         .setPaymentActivation(capabilities.paymentActivation())
+        .setDeleteSync(capabilities.deleteSync())
         .build();
   }
 
@@ -104,7 +105,7 @@ public class ProfileGrpcHelper {
       final ProfileBadgeConverter profileBadgeConverter) {
     final GetUnversionedProfileResponse.Builder responseBuilder = GetUnversionedProfileResponse.newBuilder()
         .setIdentityKey(ByteString.copyFrom(targetAccount.getIdentityKey(targetIdentifier.identityType()).serialize()))
-        .setCapabilities(buildUserCapabilities(new org.whispersystems.textsecuregcm.entities.UserCapabilities()));
+        .setCapabilities(buildUserCapabilities(org.whispersystems.textsecuregcm.entities.UserCapabilities.createForAccount(targetAccount)));
 
     switch (targetIdentifier.identityType()) {
       case ACI -> {

service/src/main/java/org/whispersystems/textsecuregcm/storage/Account.java

@@ -292,6 +292,10 @@ public class Account {
     return allEnabledDevicesHaveCapability(DeviceCapabilities::paymentActivation);
   }
 
+  public boolean isDeleteSyncSupported() {
+    return allEnabledDevicesHaveCapability(DeviceCapabilities::deleteSync);
+  }
+
   private boolean allEnabledDevicesHaveCapability(final Predicate<DeviceCapabilities> predicate) {
     requireNotStale();
 

service/src/main/java/org/whispersystems/textsecuregcm/storage/Device.java

@@ -248,6 +248,6 @@ public class Device {
     return this.userAgent;
   }
 
-  public record DeviceCapabilities(boolean storage, boolean transfer, boolean paymentActivation) {
+  public record DeviceCapabilities(boolean storage, boolean transfer, boolean paymentActivation, boolean deleteSync) {
   }
 }

service/src/main/proto/org/signal/chat/device.proto

@@ -148,6 +148,7 @@ message SetCapabilitiesRequest {
   bool storage = 1;
   bool transfer = 2;
   bool paymentActivation = 3;
+  bool deleteSync = 4;
 }
 
 message SetCapabilitiesResponse {}

service/src/main/proto/org/signal/chat/profile.proto

@@ -322,6 +322,10 @@ message UserCapabilities {
    * Whether all devices linked to the account support MobileCoin payments.
    */
   bool payment_activation = 1;
+  /**
+   * Whether all devices linked to the account support delete syncing
+   */
+  bool delete_sync = 2;
 }
 
 message Badge {

service/src/test/java/org/whispersystems/textsecuregcm/controllers/DeviceControllerTest.java

@@ -218,7 +218,8 @@ class DeviceControllerTest {
 
     when(asyncCommands.set(any(), any(), any())).thenReturn(MockRedisFuture.completedFuture(null));
 
-    final AccountAttributes accountAttributes = new AccountAttributes(fetchesMessages, 1234, 5678, null, null, true, new DeviceCapabilities(true, true, true));
+    final AccountAttributes accountAttributes = new AccountAttributes(fetchesMessages, 1234, 5678, null,
+        null, true, new DeviceCapabilities(true, true, true, false));
 
     final LinkDeviceRequest request = new LinkDeviceRequest(deviceCode.verificationCode(),
         accountAttributes,
@@ -264,6 +265,58 @@ class DeviceControllerTest {
     );
   }
 
+  @ParameterizedTest
+  @MethodSource
+  void deviceDowngradeDeleteSync(final boolean accountSupportsDeleteSync, final boolean deviceSupportsDeleteSync, final int expectedStatus) {
+    when(accountsManager.getByAccountIdentifier(AuthHelper.VALID_UUID)).thenReturn(Optional.of(account));
+    when(accountsManager.addDevice(any(), any()))
+            .thenReturn(CompletableFuture.completedFuture(new Pair<>(mock(Account.class), mock(Device.class))));
+
+    final Device primaryDevice = mock(Device.class);
+    when(primaryDevice.getId()).thenReturn(Device.PRIMARY_ID);
+    when(AuthHelper.VALID_ACCOUNT.getDevices()).thenReturn(List.of(primaryDevice));
+
+    final ECSignedPreKey aciSignedPreKey;
+    final ECSignedPreKey pniSignedPreKey;
+    final KEMSignedPreKey aciPqLastResortPreKey;
+    final KEMSignedPreKey pniPqLastResortPreKey;
+
+    final ECKeyPair aciIdentityKeyPair = Curve.generateKeyPair();
+    final ECKeyPair pniIdentityKeyPair = Curve.generateKeyPair();
+
+    aciSignedPreKey = KeysHelper.signedECPreKey(1, aciIdentityKeyPair);
+    pniSignedPreKey = KeysHelper.signedECPreKey(2, pniIdentityKeyPair);
+    aciPqLastResortPreKey = KeysHelper.signedKEMPreKey(3, aciIdentityKeyPair);
+    pniPqLastResortPreKey = KeysHelper.signedKEMPreKey(4, pniIdentityKeyPair);
+
+    when(account.getIdentityKey(IdentityType.ACI)).thenReturn(new IdentityKey(aciIdentityKeyPair.getPublicKey()));
+    when(account.getIdentityKey(IdentityType.PNI)).thenReturn(new IdentityKey(pniIdentityKeyPair.getPublicKey()));
+    when(account.isDeleteSyncSupported()).thenReturn(accountSupportsDeleteSync);
+
+    when(asyncCommands.set(any(), any(), any())).thenReturn(MockRedisFuture.completedFuture(null));
+
+    final LinkDeviceRequest request = new LinkDeviceRequest(deviceController.generateVerificationToken(AuthHelper.VALID_UUID),
+            new AccountAttributes(false, 1234, 5678, null, null, true, new DeviceCapabilities(true, true, true, deviceSupportsDeleteSync)),
+            new DeviceActivationRequest(aciSignedPreKey, pniSignedPreKey, aciPqLastResortPreKey, pniPqLastResortPreKey, Optional.empty(), Optional.of(new GcmRegistrationId("gcm-id"))));
+
+    try (final Response response = resources.getJerseyTest()
+            .target("/v1/devices/link")
+            .request()
+            .header("Authorization", AuthHelper.getProvisioningAuthHeader(AuthHelper.VALID_NUMBER, "password1"))
+            .put(Entity.entity(request, MediaType.APPLICATION_JSON_TYPE))) {
+
+      assertEquals(expectedStatus, response.getStatus());
+    }
+  }
+
+  private static List<Arguments> deviceDowngradeDeleteSync() {
+    return List.of(
+            Arguments.of(true, true, 200),
+            Arguments.of(true, false, 409),
+            Arguments.of(false, true, 200),
+            Arguments.of(false, false, 200));
+  }
+
   @Test
   void linkDeviceAtomicBadCredentials() {
     when(accountsManager.getByAccountIdentifier(AuthHelper.VALID_UUID)).thenReturn(Optional.of(account));
@@ -633,7 +686,7 @@ class DeviceControllerTest {
     when(asyncCommands.set(any(), any(), any())).thenReturn(MockRedisFuture.completedFuture(null));
 
     final LinkDeviceRequest request = new LinkDeviceRequest(deviceCode.verificationCode(),
-        new AccountAttributes(false, registrationId, pniRegistrationId, null, null, true, new DeviceCapabilities(true, true, true)),
+        new AccountAttributes(false, registrationId, pniRegistrationId, null, null, true, new DeviceCapabilities(true, true, true, false)),
         new DeviceActivationRequest(aciSignedPreKey, pniSignedPreKey, aciPqLastResortPreKey, pniPqLastResortPreKey, Optional.of(new ApnRegistrationId("apn", null)), Optional.empty()));
 
     try (final Response response = resources.getJerseyTest()
@@ -692,7 +745,7 @@ class DeviceControllerTest {
 
   @Test
   void putCapabilitiesSuccessTest() {
-    final DeviceCapabilities deviceCapabilities = new DeviceCapabilities(true, true, true);
+    final DeviceCapabilities deviceCapabilities = new DeviceCapabilities(true, true, true, false);
     final Response response = resources
         .getJerseyTest()
         .target("/v1/devices/capabilities")

service/src/test/java/org/whispersystems/textsecuregcm/controllers/ProfileControllerTest.java

@@ -144,6 +144,7 @@ class ProfileControllerTest {
 
   private DynamicPaymentsConfiguration dynamicPaymentsConfiguration;
   private Account profileAccount;
+  private Account capabilitiesAccount;
 
   private static final ResourceExtension resources = ResourceExtension.builder()
       .addProperty(ServerProperties.UNWRAP_COMPLETION_STAGE_IN_WRITER_ENABLE, Boolean.TRUE)
@@ -203,12 +204,11 @@ class ProfileControllerTest {
     when(profileAccount.getUsernameHash()).thenReturn(Optional.of(USERNAME_HASH));
     when(profileAccount.getUnidentifiedAccessKey()).thenReturn(Optional.of(UNIDENTIFIED_ACCESS_KEY));
 
-    Account capabilitiesAccount = mock(Account.class);
+    capabilitiesAccount = mock(Account.class);
 
     when(capabilitiesAccount.getUuid()).thenReturn(AuthHelper.VALID_UUID);
     when(capabilitiesAccount.getIdentityKey(IdentityType.ACI)).thenReturn(ACCOUNT_IDENTITY_KEY);
     when(capabilitiesAccount.getIdentityKey(IdentityType.PNI)).thenReturn(ACCOUNT_PHONE_NUMBER_IDENTITY_KEY);
-    when(capabilitiesAccount.isPaymentActivationSupported()).thenReturn(false);
     when(capabilitiesAccount.isEnabled()).thenReturn(true);
 
     when(accountsManager.getByServiceIdentifier(any())).thenReturn(Optional.empty());
@@ -439,14 +439,17 @@ class ProfileControllerTest {
     assertThat(response.getStatus()).isEqualTo(401);
   }
 
-  @Test
+  @ParameterizedTest
-  void testProfileCapabilities() {
+  @ValueSource(booleans = {true, false})
+  void testProfileCapabilities(final boolean isDeleteSyncSupported) {
+    when(capabilitiesAccount.isDeleteSyncSupported()).thenReturn(isDeleteSyncSupported);
     final BaseProfileResponse profile = resources.getJerseyTest()
         .target("/v1/profile/" + AuthHelper.VALID_UUID)
         .request()
         .header("Authorization", AuthHelper.getAuthHeader(AuthHelper.VALID_UUID, AuthHelper.VALID_PASSWORD))
         .get(BaseProfileResponse.class);
 
+    assertEquals(isDeleteSyncSupported, profile.getCapabilities().deleteSync());
     assertThat(profile.getCapabilities().paymentActivation()).isTrue();
   }
 

service/src/test/java/org/whispersystems/textsecuregcm/controllers/RegistrationControllerTest.java

@@ -477,10 +477,10 @@ class RegistrationControllerTest {
     }
 
     final AccountAttributes fetchesMessagesAccountAttributes =
-        new AccountAttributes(true, 1, 1, "test".getBytes(StandardCharsets.UTF_8), null, true, new Device.DeviceCapabilities(false, false, false));
+        new AccountAttributes(true, 1, 1, "test".getBytes(StandardCharsets.UTF_8), null, true, new Device.DeviceCapabilities(false, false, false, false));
 
     final AccountAttributes pushAccountAttributes =
-        new AccountAttributes(false, 1, 1, "test".getBytes(StandardCharsets.UTF_8), null, true, new Device.DeviceCapabilities(false, false, false));
+        new AccountAttributes(false, 1, 1, "test".getBytes(StandardCharsets.UTF_8), null, true, new Device.DeviceCapabilities(false, false, false, false));
 
     return Stream.of(
         // "Fetches messages" is true, but an APNs token is provided
@@ -566,7 +566,7 @@ class RegistrationControllerTest {
     }
 
     final AccountAttributes accountAttributes =
-        new AccountAttributes(true, 1, 1, "test".getBytes(StandardCharsets.UTF_8), null, true, new Device.DeviceCapabilities(false, false, false));
+        new AccountAttributes(true, 1, 1, "test".getBytes(StandardCharsets.UTF_8), null, true, new Device.DeviceCapabilities(false, false, false, false));
 
     return Stream.of(
         // Signed PNI EC pre-key is missing
@@ -736,13 +736,13 @@ class RegistrationControllerTest {
     final int registrationId = 1;
     final int pniRegistrationId = 2;
 
-    final Device.DeviceCapabilities deviceCapabilities = new Device.DeviceCapabilities(false, false, false);
+    final Device.DeviceCapabilities deviceCapabilities = new Device.DeviceCapabilities(false, false, false, false);
 
     final AccountAttributes fetchesMessagesAccountAttributes =
-        new AccountAttributes(true, registrationId, pniRegistrationId, "test".getBytes(StandardCharsets.UTF_8), null, true, new Device.DeviceCapabilities(false, false, false));
+        new AccountAttributes(true, registrationId, pniRegistrationId, "test".getBytes(StandardCharsets.UTF_8), null, true, new Device.DeviceCapabilities(false, false, false, false));
 
     final AccountAttributes pushAccountAttributes =
-        new AccountAttributes(false, registrationId, pniRegistrationId, "test".getBytes(StandardCharsets.UTF_8), null, true, new Device.DeviceCapabilities(false, false, false));
+        new AccountAttributes(false, registrationId, pniRegistrationId, "test".getBytes(StandardCharsets.UTF_8), null, true, new Device.DeviceCapabilities(false, false, false, false));
 
     final String apnsToken = "apns-token";
     final String apnsVoipToken = "apns-voip-token";
@@ -857,7 +857,7 @@ class RegistrationControllerTest {
     final IdentityKey pniIdentityKey = new IdentityKey(pniIdentityKeyPair.getPublicKey());
 
     final AccountAttributes accountAttributes = new AccountAttributes(true, registrationId, pniRegistrationId, "name".getBytes(StandardCharsets.UTF_8), "reglock",
-            true, new Device.DeviceCapabilities(true, true, true));
+            true, new Device.DeviceCapabilities(true, true, true, false));
 
     final RegistrationRequest request = new RegistrationRequest(
         Base64.getEncoder().encodeToString(sessionId.getBytes(StandardCharsets.UTF_8)),

service/src/test/java/org/whispersystems/textsecuregcm/grpc/DevicesGrpcServiceTest.java

@@ -393,7 +393,8 @@ class DevicesGrpcServiceTest extends SimpleBaseGrpcTest<DevicesGrpcService, Devi
       @CartesianTest.Values(bytes = {Device.PRIMARY_ID, Device.PRIMARY_ID + 1}) final byte deviceId,
       @CartesianTest.Values(booleans = {true, false}) final boolean storage,
       @CartesianTest.Values(booleans = {true, false}) final boolean transfer,
-      @CartesianTest.Values(booleans = {true, false}) final boolean paymentActivation) {
+      @CartesianTest.Values(booleans = {true, false}) final boolean paymentActivation,
+      @CartesianTest.Values(booleans = {true, false}) final boolean deleteSync) {
 
     mockAuthenticationInterceptor().setAuthenticatedDevice(AUTHENTICATED_ACI, deviceId);
 
@@ -404,12 +405,14 @@ class DevicesGrpcServiceTest extends SimpleBaseGrpcTest<DevicesGrpcService, Devi
             .setStorage(storage)
             .setTransfer(transfer)
             .setPaymentActivation(paymentActivation)
+            .setDeleteSync(deleteSync)
         .build());
 
     final Device.DeviceCapabilities expectedCapabilities = new Device.DeviceCapabilities(
         storage,
         transfer,
-        paymentActivation);
+        paymentActivation,
+        deleteSync);
 
     verify(device).setCapabilities(expectedCapabilities);
   }

service/src/test/java/org/whispersystems/textsecuregcm/grpc/ProfileAnonymousGrpcServiceTest.java

@@ -162,7 +162,7 @@ public class ProfileAnonymousGrpcServiceTest extends SimpleBaseGrpcTest<ProfileA
         .setIdentityKey(ByteString.copyFrom(identityKey.serialize()))
         .setUnidentifiedAccess(ByteString.copyFrom(unidentifiedAccessChecksum))
         .setUnrestrictedUnidentifiedAccess(false)
-        .setCapabilities(ProfileGrpcHelper.buildUserCapabilities(new UserCapabilities()))
+        .setCapabilities(ProfileGrpcHelper.buildUserCapabilities(UserCapabilities.createForAccount(account)))
         .addAllBadges(ProfileGrpcHelper.buildBadges(badges))
         .build();
 
@@ -214,7 +214,7 @@ public class ProfileAnonymousGrpcServiceTest extends SimpleBaseGrpcTest<ProfileA
     final GetUnversionedProfileResponse expectedResponse = GetUnversionedProfileResponse.newBuilder()
         .setIdentityKey(ByteString.copyFrom(identityKey.serialize()))
         .setUnrestrictedUnidentifiedAccess(false)
-        .setCapabilities(ProfileGrpcHelper.buildUserCapabilities(new UserCapabilities()))
+        .setCapabilities(ProfileGrpcHelper.buildUserCapabilities(UserCapabilities.createForAccount(account)))
         .addAllBadges(ProfileGrpcHelper.buildBadges(badges))
         .build();
 

service/src/test/java/org/whispersystems/textsecuregcm/grpc/ProfileGrpcServiceTest.java

@@ -436,7 +436,7 @@ public class ProfileGrpcServiceTest extends SimpleBaseGrpcTest<ProfileGrpcServic
         .setIdentityKey(ByteString.copyFrom(identityKey.serialize()))
         .setUnidentifiedAccess(ByteString.copyFrom(unidentifiedAccessChecksum))
         .setUnrestrictedUnidentifiedAccess(true)
-        .setCapabilities(ProfileGrpcHelper.buildUserCapabilities(new UserCapabilities()))
+        .setCapabilities(ProfileGrpcHelper.buildUserCapabilities(UserCapabilities.createForAccount(account)))
         .addAllBadges(ProfileGrpcHelper.buildBadges(badges))
         .build();
 

service/src/test/java/org/whispersystems/textsecuregcm/storage/AccountCreationDeletionIntegrationTest.java

@@ -184,6 +184,7 @@ public class AccountCreationDeletionIntegrationTest {
     final String registrationLockSecret = RandomStringUtils.randomAlphanumeric(16);
 
     final Device.DeviceCapabilities deviceCapabilities = new Device.DeviceCapabilities(
+        ThreadLocalRandom.current().nextBoolean(),
         ThreadLocalRandom.current().nextBoolean(),
         ThreadLocalRandom.current().nextBoolean(),
         ThreadLocalRandom.current().nextBoolean());
@@ -296,14 +297,14 @@ public class AccountCreationDeletionIntegrationTest {
       final KEMSignedPreKey pniPqLastResortPreKey = KeysHelper.signedKEMPreKey(4, pniKeyPair);
 
       final Account originalAccount = accountsManager.create(number,
-          new AccountAttributes(true, 1, 1, "name".getBytes(StandardCharsets.UTF_8), "registration-lock", false, new Device.DeviceCapabilities(false, false, false)),
+          new AccountAttributes(true, 1, 1, "name".getBytes(StandardCharsets.UTF_8), "registration-lock", false, new Device.DeviceCapabilities(false, false, false, false)),
           Collections.emptyList(),
           new IdentityKey(aciKeyPair.getPublicKey()),
           new IdentityKey(pniKeyPair.getPublicKey()),
           new DeviceSpec(null,
               "password?",
               "OWI",
-              new Device.DeviceCapabilities(false, false, false),
+              new Device.DeviceCapabilities(false, false, false, false),
               1,
               2,
               true,
@@ -325,6 +326,7 @@ public class AccountCreationDeletionIntegrationTest {
     final String registrationLockSecret = RandomStringUtils.randomAlphanumeric(16);
 
     final Device.DeviceCapabilities deviceCapabilities = new Device.DeviceCapabilities(
+        ThreadLocalRandom.current().nextBoolean(),
         ThreadLocalRandom.current().nextBoolean(),
         ThreadLocalRandom.current().nextBoolean(),
         ThreadLocalRandom.current().nextBoolean());
@@ -414,6 +416,7 @@ public class AccountCreationDeletionIntegrationTest {
     final String registrationLockSecret = RandomStringUtils.randomAlphanumeric(16);
 
     final Device.DeviceCapabilities deviceCapabilities = new Device.DeviceCapabilities(
+        ThreadLocalRandom.current().nextBoolean(),
         ThreadLocalRandom.current().nextBoolean(),
         ThreadLocalRandom.current().nextBoolean(),
         ThreadLocalRandom.current().nextBoolean());

service/src/test/java/org/whispersystems/textsecuregcm/storage/AccountTest.java

@@ -49,6 +49,8 @@ class AccountTest {
   private final Device paymentActivationCapableDevice = mock(Device.class);
   private final Device paymentActivationIncapableDevice = mock(Device.class);
   private final Device paymentActivationIncapableExpiredDevice = mock(Device.class);
+  private final Device deleteSyncCapableDevice = mock(Device.class);
+  private final Device deleteSyncIncapableDevice = mock(Device.class);
 
   @BeforeEach
   void setup() {
@@ -74,15 +76,24 @@ class AccountTest {
     when(oldSecondaryDevice.getId()).thenReturn(deviceId2);
 
     when(paymentActivationCapableDevice.getCapabilities()).thenReturn(
-        new DeviceCapabilities(true, true, true));
+        new DeviceCapabilities(true, true, true, false));
     when(paymentActivationCapableDevice.hasMessageDeliveryChannel()).thenReturn(true);
     when(paymentActivationIncapableDevice.getCapabilities()).thenReturn(
-        new DeviceCapabilities(true, true, false));
+        new DeviceCapabilities(true, true, false, false));
     when(paymentActivationIncapableDevice.hasMessageDeliveryChannel()).thenReturn(true);
     when(paymentActivationIncapableExpiredDevice.getCapabilities()).thenReturn(
-        new DeviceCapabilities(true, true, false));
+        new DeviceCapabilities(true, true, false, false));
     when(paymentActivationIncapableExpiredDevice.hasMessageDeliveryChannel()).thenReturn(false);
 
+    when(deleteSyncCapableDevice.getCapabilities()).thenReturn(
+        new DeviceCapabilities(true, true, true, true)
+    );
+    when(deleteSyncCapableDevice.hasMessageDeliveryChannel()).thenReturn(true);
+    when(deleteSyncIncapableDevice.getCapabilities()).thenReturn(
+        new DeviceCapabilities(true, true, true, false)
+    );
+    when(deleteSyncIncapableDevice.hasMessageDeliveryChannel()).thenReturn(true);
+
   }
 
   @Test
@@ -184,6 +195,16 @@ class AccountTest {
         "1234".getBytes(StandardCharsets.UTF_8)).isPaymentActivationSupported()).isTrue();
   }
 
+  @Test
+  void isDeleteSyncSupported() {
+    assertTrue(AccountsHelper.generateTestAccount("+18005551234", UUID.randomUUID(), UUID.randomUUID(),
+        List.of(deleteSyncCapableDevice),
+        "1234".getBytes(StandardCharsets.UTF_8)).isDeleteSyncSupported());
+    assertFalse(AccountsHelper.generateTestAccount("+18005551234", UUID.randomUUID(), UUID.randomUUID(),
+        List.of(deleteSyncCapableDevice, deleteSyncIncapableDevice),
+        "1234".getBytes(StandardCharsets.UTF_8)).isDeleteSyncSupported());
+  }
+
   @Test
   void stale() {
     final Account account = AccountsHelper.generateTestAccount("+14151234567", UUID.randomUUID(), UUID.randomUUID(), Collections.emptyList(),

service/src/test/java/org/whispersystems/textsecuregcm/storage/AccountsManagerChangeNumberIntegrationTest.java

@@ -193,7 +193,7 @@ class AccountsManagerChangeNumberIntegrationTest {
     final int rotatedPniRegistrationId = 17;
     final ECKeyPair rotatedPniIdentityKeyPair = Curve.generateKeyPair();
     final ECSignedPreKey rotatedSignedPreKey = KeysHelper.signedECPreKey(1L, rotatedPniIdentityKeyPair);
-    final AccountAttributes accountAttributes = new AccountAttributes(true, rotatedPniRegistrationId + 1, rotatedPniRegistrationId, "test".getBytes(StandardCharsets.UTF_8), null, true, new Device.DeviceCapabilities(false, false, false));
+    final AccountAttributes accountAttributes = new AccountAttributes(true, rotatedPniRegistrationId + 1, rotatedPniRegistrationId, "test".getBytes(StandardCharsets.UTF_8), null, true, new Device.DeviceCapabilities(false, false, false, false));
     final Account account = AccountsHelper.createAccount(accountsManager, originalNumber, accountAttributes);
 
     keysManager.storeEcSignedPreKeys(account.getIdentifier(IdentityType.ACI),

service/src/test/java/org/whispersystems/textsecuregcm/storage/AccountsManagerConcurrentModificationIntegrationTest.java

@@ -156,7 +156,7 @@ class AccountsManagerConcurrentModificationIntegrationTest {
                   null,
                   "password",
                   null,
-                  new Device.DeviceCapabilities(false, false, false),
+                  new Device.DeviceCapabilities(false, false, false, false),
                   1,
                   2,
                   true,

service/src/test/java/org/whispersystems/textsecuregcm/storage/AccountsManagerTest.java

@@ -876,7 +876,7 @@ class AccountsManagerTest {
   @ValueSource(booleans = {true, false})
   void testCreateWithStorageCapability(final boolean hasStorage) throws InterruptedException {
     final AccountAttributes attributes = new AccountAttributes(false, 1, 2, null, null,
-            true, new DeviceCapabilities(hasStorage, false, false));
+            true, new DeviceCapabilities(hasStorage, false, false, false));
 
     final Account account = createAccount("+18005550123", attributes);
 
@@ -901,7 +901,7 @@ class AccountsManagerTest {
     final byte[] deviceNameCiphertext = "device-name".getBytes(StandardCharsets.UTF_8);
     final String password = "password";
     final String signalAgent = "OWT";
-    final DeviceCapabilities deviceCapabilities = new DeviceCapabilities(true, true, true);
+    final DeviceCapabilities deviceCapabilities = new DeviceCapabilities(true, true, true, false);
     final int aciRegistrationId = 17;
     final int pniRegistrationId = 19;
     final ECSignedPreKey aciSignedPreKey = KeysHelper.signedECPreKey(1, aciKeyPair);

service/src/test/java/org/whispersystems/textsecuregcm/storage/AddRemoveDeviceIntegrationTest.java

@@ -172,7 +172,7 @@ public class AddRemoveDeviceIntegrationTest {
                 "device-name".getBytes(StandardCharsets.UTF_8),
                 "password",
                 "OWT",
-                new Device.DeviceCapabilities(true, true, true),
+                new Device.DeviceCapabilities(true, true, true, false),
                 1,
                 2,
                 true,
@@ -215,7 +215,7 @@ public class AddRemoveDeviceIntegrationTest {
                 "device-name".getBytes(StandardCharsets.UTF_8),
                 "password",
                 "OWT",
-                new Device.DeviceCapabilities(true, true, true),
+                new Device.DeviceCapabilities(true, true, true, false),
                 1,
                 2,
                 true,
@@ -268,7 +268,7 @@ public class AddRemoveDeviceIntegrationTest {
                 "device-name".getBytes(StandardCharsets.UTF_8),
                 "password",
                 "OWT",
-                new Device.DeviceCapabilities(true, true, true),
+                new Device.DeviceCapabilities(true, true, true, false),
                 1,
                 2,
                 true,

service/src/test/java/org/whispersystems/textsecuregcm/tests/util/AccountsHelper.java

@@ -149,6 +149,7 @@ public class AccountsHelper {
           case "isDiscoverableByPhoneNumber" -> when(updatedAccount.isDiscoverableByPhoneNumber()).thenAnswer(stubbing);
           case "getNextDeviceId" -> when(updatedAccount.getNextDeviceId()).thenAnswer(stubbing);
           case "isPaymentActivationSupported" -> when(updatedAccount.isPaymentActivationSupported()).thenAnswer(stubbing);
+          case "isDeleteSyncSupported" -> when(updatedAccount.isDeleteSyncSupported()).thenAnswer(stubbing);
           case "hasEnabledLinkedDevice" -> when(updatedAccount.hasEnabledLinkedDevice()).thenAnswer(stubbing);
           case "getRegistrationLock" -> when(updatedAccount.getRegistrationLock()).thenAnswer(stubbing);
           case "getIdentityKey" ->