X-Git-Url: https://git.nmode.ca/signal-cli/blobdiff_plain/591c0fe8a3744608575a6dcb1f6f4f9f818948d2..5c754b6f5d5bd3273b3c0722cf3eabbcd02c20b9:/src/main/java/org/asamk/signal/manager/GroupUtils.java

diff --git a/src/main/java/org/asamk/signal/manager/GroupUtils.java b/src/main/java/org/asamk/signal/manager/GroupUtils.java
index f4398f94..d86dfbe9 100644
--- a/src/main/java/org/asamk/signal/manager/GroupUtils.java
+++ b/src/main/java/org/asamk/signal/manager/GroupUtils.java
@@ -3,8 +3,13 @@ package org.asamk.signal.manager;
 import org.asamk.signal.storage.groups.GroupInfo;
 import org.asamk.signal.storage.groups.GroupInfoV1;
 import org.asamk.signal.storage.groups.GroupInfoV2;
+import org.signal.zkgroup.InvalidInputException;
+import org.signal.zkgroup.groups.GroupMasterKey;
+import org.signal.zkgroup.groups.GroupSecretParams;
+import org.whispersystems.libsignal.kdf.HKDFv3;
 import org.whispersystems.signalservice.api.messages.SignalServiceDataMessage;
 import org.whispersystems.signalservice.api.messages.SignalServiceGroup;
+import org.whispersystems.signalservice.api.messages.SignalServiceGroupContext;
 import org.whispersystems.signalservice.api.messages.SignalServiceGroupV2;
 
 public class GroupUtils {
@@ -14,7 +19,7 @@ public class GroupUtils {
     ) {
         if (groupInfo instanceof GroupInfoV1) {
             SignalServiceGroup group = SignalServiceGroup.newBuilder(SignalServiceGroup.Type.DELIVER)
-                    .withId(groupInfo.groupId)
+                    .withId(groupInfo.getGroupId().serialize())
                     .build();
             messageBuilder.asGroupMessage(group);
         } else {
@@ -25,4 +30,39 @@ public class GroupUtils {
             messageBuilder.asGroupMessage(group);
         }
     }
+
+    public static GroupId getGroupId(SignalServiceGroupContext context) {
+        if (context.getGroupV1().isPresent()) {
+            return GroupId.v1(context.getGroupV1().get().getGroupId());
+        } else if (context.getGroupV2().isPresent()) {
+            return getGroupIdV2(context.getGroupV2().get().getMasterKey());
+        } else {
+            return null;
+        }
+    }
+
+    public static GroupIdV2 getGroupIdV2(GroupSecretParams groupSecretParams) {
+        return GroupId.v2(groupSecretParams.getPublicParams().getGroupIdentifier().serialize());
+    }
+
+    public static GroupIdV2 getGroupIdV2(GroupMasterKey groupMasterKey) {
+        final GroupSecretParams groupSecretParams = GroupSecretParams.deriveFromMasterKey(groupMasterKey);
+        return getGroupIdV2(groupSecretParams);
+    }
+
+    public static GroupIdV2 getGroupIdV2(GroupIdV1 groupIdV1) {
+        final GroupSecretParams groupSecretParams = GroupSecretParams.deriveFromMasterKey(deriveV2MigrationMasterKey(
+                groupIdV1));
+        return getGroupIdV2(groupSecretParams);
+    }
+
+    private static GroupMasterKey deriveV2MigrationMasterKey(GroupIdV1 groupIdV1) {
+        try {
+            return new GroupMasterKey(new HKDFv3().deriveSecrets(groupIdV1.serialize(),
+                    "GV2 Migration".getBytes(),
+                    GroupMasterKey.SIZE));
+        } catch (InvalidInputException e) {
+            throw new AssertionError(e);
+        }
+    }
 }