Merge pull request #2389 from vitorpamplona/claude/fix-marmot-group-persistence-6Cfb7

Fix GCM IV length in KeyStore decryption

amethyst/src/main/java/com/vitorpamplona/amethyst/model/preferences/KeyStoreEncryption.kt

@@ -38,6 +38,7 @@ class KeyStoreEncryption {
         private const val TRANSFORMATION = "$ALGORITHM/$BLOCK_MODE/$PADDING"
         private const val PURPOSE = KeyProperties.PURPOSE_ENCRYPT or KeyProperties.PURPOSE_DECRYPT
         private const val KEY_ALIAS = "AMETHYST_AES_KEY"
+        private const val GCM_IV_LENGTH = 12
     }
 
     private val cipher = Cipher.getInstance(TRANSFORMATION)
@@ -93,9 +94,11 @@ class KeyStoreEncryption {
     }
 
     fun decrypt(bytes: ByteArray): ByteArray? {
-        // Extracts IV and decrypts the data
+        // Extracts IV and decrypts the data. GCM mode uses a 12-byte IV,
-        val iv = bytes.copyOfRange(0, cipher.blockSize)
+        // which is what cipher.iv returns in encrypt() — not the AES block
-        val data = bytes.copyOfRange(cipher.blockSize, bytes.size)
+        // size (16), which is what cipher.blockSize would return.
+        val iv = bytes.copyOfRange(0, GCM_IV_LENGTH)
+        val data = bytes.copyOfRange(GCM_IV_LENGTH, bytes.size)
         cipher.init(Cipher.DECRYPT_MODE, getKey(), IvParameterSpec(iv))
         return cipher.doFinal(data)
     }

quartz/src/commonMain/kotlin/com/vitorpamplona/quartz/marmot/MarmotInboundProcessor.kt

@@ -35,6 +35,8 @@ import com.vitorpamplona.quartz.marmot.mls.group.MlsGroupManager
 import com.vitorpamplona.quartz.nip01Core.core.Event
 import com.vitorpamplona.quartz.nip01Core.core.HexKey
 import com.vitorpamplona.quartz.nip01Core.core.hexToByteArray
+import kotlinx.coroutines.sync.Mutex
+import kotlinx.coroutines.sync.withLock
 import kotlin.io.encoding.Base64
 import kotlin.io.encoding.ExperimentalEncodingApi
 
@@ -126,7 +128,7 @@ class MarmotInboundProcessor(
     private val keyPackageRotationManager: KeyPackageRotationManager,
 ) {
     private val commitTracker = CommitOrdering.EpochCommitTracker()
-    private val processedIdsLock = Any()
+    private val processedIdsMutex = Mutex()
     private val processedEventIds = LinkedHashSet<String>()
 
     companion object {
@@ -156,11 +158,12 @@ class MarmotInboundProcessor(
     suspend fun processGroupEvent(groupEvent: GroupEvent): GroupEventResult {
         // Deduplicate already-processed events (thread-safe)
         val eventId = groupEvent.id
-        synchronized(processedIdsLock) {
+        val alreadyProcessed =
-            if (eventId in processedEventIds) {
+            processedIdsMutex.withLock {
-                val gId = groupEvent.groupId()
+                eventId in processedEventIds
-                return GroupEventResult.Duplicate(gId ?: "")
             }
+        if (alreadyProcessed) {
+            return GroupEventResult.Duplicate(groupEvent.groupId() ?: "")
         }
 
         val groupId =
@@ -189,7 +192,7 @@ class MarmotInboundProcessor(
             }
 
         // Track ALL processed events for deduplication (including errors to prevent replay DoS)
-        synchronized(processedIdsLock) {
+        processedIdsMutex.withLock {
             processedEventIds.add(eventId)
             // Trim the set if it exceeds the max size
             if (processedEventIds.size > MAX_PROCESSED_IDS) {
@@ -288,12 +291,12 @@ class MarmotInboundProcessor(
     /**
      * Get all (group, epoch) keys that have pending unresolved commits.
      */
-    fun pendingCommitGroupEpochs(): Set<CommitOrdering.GroupEpochKey> = commitTracker.pendingGroupEpochs()
+    suspend fun pendingCommitGroupEpochs(): Set<CommitOrdering.GroupEpochKey> = commitTracker.pendingGroupEpochs()
 
     /**
      * Clear all pending commit state.
      */
-    fun clearPendingCommits() {
+    suspend fun clearPendingCommits() {
         commitTracker.clear()
     }
 

quartz/src/commonMain/kotlin/com/vitorpamplona/quartz/marmot/mip03GroupMessages/CommitOrdering.kt

@@ -20,6 +20,9 @@
  */
 package com.vitorpamplona.quartz.marmot.mip03GroupMessages
 
+import kotlinx.coroutines.sync.Mutex
+import kotlinx.coroutines.sync.withLock
+
 /**
  * Deterministic commit conflict resolution for MLS over Nostr (MIP-03).
  *
@@ -82,7 +85,7 @@ object CommitOrdering {
      * to determine which commit wins for each (group, epoch).
      */
     class EpochCommitTracker {
-        private val lock = Any()
+        private val mutex = Mutex()
         private val pendingByGroupEpoch = mutableMapOf<GroupEpochKey, MutableList<GroupEvent>>()
 
         companion object {
@@ -97,11 +100,11 @@ object CommitOrdering {
          * @param epoch the MLS epoch number this commit targets
          * @param commit the GroupEvent containing the commit
          */
-        fun addCommit(
+        suspend fun addCommit(
             groupId: String,
             epoch: Long,
             commit: GroupEvent,
-        ) = synchronized(lock) {
+        ) = mutex.withLock {
             val key = GroupEpochKey(groupId, epoch)
             pendingByGroupEpoch.getOrPut(key) { mutableListOf() }.add(commit)
 
@@ -120,11 +123,11 @@ object CommitOrdering {
         /**
          * Returns pending commits for a specific group and epoch.
          */
-        fun pendingForEpoch(
+        suspend fun pendingForEpoch(
             groupId: String,
             epoch: Long,
         ): List<GroupEvent> =
-            synchronized(lock) {
+            mutex.withLock {
                 pendingByGroupEpoch[GroupEpochKey(groupId, epoch)]?.toList() ?: emptyList()
             }
 
@@ -135,37 +138,38 @@ object CommitOrdering {
          * @param epoch the MLS epoch to resolve
          * @return the winning commit, or null if no commits exist for this (group, epoch)
          */
-        fun resolve(
+        suspend fun resolve(
             groupId: String,
             epoch: Long,
         ): GroupEvent? =
-            synchronized(lock) {
+            mutex.withLock {
                 selectWinner(pendingByGroupEpoch[GroupEpochKey(groupId, epoch)] ?: emptyList())
             }
 
         /**
          * Clears pending commits for a (group, epoch) after it has been resolved.
          */
-        fun clearEpoch(
+        suspend fun clearEpoch(
             groupId: String,
             epoch: Long,
-        ) = synchronized(lock) {
+        ) = mutex.withLock {
             pendingByGroupEpoch.remove(GroupEpochKey(groupId, epoch))
+            Unit
         }
 
         /**
          * Returns all (group, epoch) keys that have pending commits.
          */
-        fun pendingGroupEpochs(): Set<GroupEpochKey> =
+        suspend fun pendingGroupEpochs(): Set<GroupEpochKey> =
-            synchronized(lock) {
+            mutex.withLock {
                 pendingByGroupEpoch.keys.toSet()
             }
 
         /**
          * Clears all pending state.
          */
-        fun clear() =
+        suspend fun clear() =
-            synchronized(lock) {
+            mutex.withLock {
                 pendingByGroupEpoch.clear()
             }
     }

quartz/src/commonTest/kotlin/com/vitorpamplona/quartz/marmot/CommitOrderingTest.kt

@@ -22,6 +22,7 @@ package com.vitorpamplona.quartz.marmot
 
 import com.vitorpamplona.quartz.marmot.mip03GroupMessages.CommitOrdering
 import com.vitorpamplona.quartz.marmot.mip03GroupMessages.GroupEvent
+import kotlinx.coroutines.test.runTest
 import kotlin.test.Test
 import kotlin.test.assertEquals
 import kotlin.test.assertFalse
@@ -134,7 +135,8 @@ class CommitOrderingTest {
     // ===== EpochCommitTracker =====
 
     @Test
-    fun testEpochCommitTracker_Basic() {
+    fun testEpochCommitTracker_Basic() =
+        runTest {
             val tracker = CommitOrdering.EpochCommitTracker()
             val epoch1Commit1 = makeGroupEvent("bbb", 1000)
             val epoch1Commit2 = makeGroupEvent("aaa", 1001)
@@ -151,7 +153,8 @@ class CommitOrderingTest {
         }
 
     @Test
-    fun testEpochCommitTracker_MultipleEpochs() {
+    fun testEpochCommitTracker_MultipleEpochs() =
+        runTest {
             val tracker = CommitOrdering.EpochCommitTracker()
             val e1 = makeGroupEvent("aaa", 1000)
             val e2 = makeGroupEvent("bbb", 2000)
@@ -171,7 +174,8 @@ class CommitOrderingTest {
         }
 
     @Test
-    fun testEpochCommitTracker_ClearAll() {
+    fun testEpochCommitTracker_ClearAll() =
+        runTest {
             val tracker = CommitOrdering.EpochCommitTracker()
             tracker.addCommit(groupId, 1L, makeGroupEvent("aaa", 1000))
             tracker.addCommit(groupId, 2L, makeGroupEvent("bbb", 2000))
@@ -183,7 +187,8 @@ class CommitOrderingTest {
         }
 
     @Test
-    fun testEpochCommitTracker_ResolveEmpty() {
+    fun testEpochCommitTracker_ResolveEmpty() =
+        runTest {
             val tracker = CommitOrdering.EpochCommitTracker()
             assertNull(tracker.resolve(groupId, 999L))
         }