Add better logging for ovesized messages.

core/util-jvm/src/main/java/org/signal/core/util/ProtoExtensions.kt

@@ -12,8 +12,10 @@ import com.squareup.wire.Message
 import com.squareup.wire.ProtoAdapter
 import com.squareup.wire.ProtoReader
 import com.squareup.wire.ProtoWriter
+import com.squareup.wire.WireField
 import okio.Buffer
 import okio.ByteString
+import okio.utf8Size
 import org.signal.core.util.logging.Log
 import java.io.IOException
 import java.util.LinkedList
@@ -87,6 +89,96 @@ fun writeUnknownEnumValue(tag: Int, enumValue: Int): ByteString {
   return buffer.readByteString()
 }
 
+/**
+ * Builds a human-readable tree of serialized sizes for this proto message,
+ * recursively descending into all nested message fields. Useful for debugging
+ * oversized messages.
+ *
+ * Example output:
+ * ```
+ * Content(1234)
+ *   dataMessage(1100)
+ *     body(500)
+ *     groupV2(400)
+ *       groupChange(350)
+ *     attachments[2](200)
+ * ```
+ */
+fun Message<*, *>.buildSizeTree(name: String): String {
+  val sb = StringBuilder()
+  appendSizeTree(name, 0, sb)
+  return sb.toString()
+}
+
+@Suppress("UNCHECKED_CAST")
+private fun Message<*, *>.appendSizeTree(name: String, depth: Int, sb: StringBuilder) {
+  val totalSize = (adapter as ProtoAdapter<Message<*, *>>).encodedSize(this)
+  repeat(depth) { sb.append("  ") }
+  sb.append(name).append("(").append(totalSize).append(")")
+
+  for (field in this.javaClass.declaredFields) {
+    field.getAnnotation(WireField::class.java) ?: continue
+
+    val value = try {
+      field.get(this)
+    } catch (_: IllegalAccessException) {
+      continue
+    } ?: continue
+
+    val fieldName = field.name
+
+    when (value) {
+      is Message<*, *> -> {
+        sb.append("\n")
+        value.appendSizeTree(fieldName, depth + 1, sb)
+      }
+      is List<*> -> {
+        if (value.isNotEmpty()) {
+          var listTotalSize = 0
+          val isMessageList = value[0] is Message<*, *>
+          for (item in value) {
+            when (item) {
+              is Message<*, *> -> listTotalSize += (item.adapter as ProtoAdapter<Message<*, *>>).encodedSize(item)
+              is ByteString -> listTotalSize += item.size
+              is String -> listTotalSize += item.utf8Size().toInt()
+            }
+          }
+          sb.append("\n")
+          repeat(depth + 1) { sb.append("  ") }
+          sb.append(fieldName).append("[").append(value.size).append("](").append(listTotalSize).append(")")
+
+          if (isMessageList) {
+            for (i in value.indices) {
+              sb.append("\n")
+              (value[i] as Message<*, *>).appendSizeTree("${fieldName}[$i]", depth + 2, sb)
+            }
+          }
+        }
+      }
+      is ByteString -> {
+        if (value.size > 0) {
+          sb.append("\n")
+          repeat(depth + 1) { sb.append("  ") }
+          sb.append(fieldName).append("(").append(value.size).append(")")
+        }
+      }
+      is String -> {
+        if (value.isNotEmpty()) {
+          sb.append("\n")
+          repeat(depth + 1) { sb.append("  ") }
+          sb.append(fieldName).append("(").append(value.utf8Size().toInt()).append(")")
+        }
+      }
+    }
+  }
+
+  if (unknownFields.size > 0) {
+    sb.append("\n")
+    repeat(depth + 1) { sb.append("  ") }
+    sb.append("unknownFields(").append(unknownFields.size).append(")")
+  }
+}
+
 /**
  * Recursively retrieves all inner complex proto types inside a given proto.
  */

lib/libsignal-service/src/main/java/org/whispersystems/signalservice/api/SignalServiceMessageSender.java

@@ -8,6 +8,7 @@ package org.whispersystems.signalservice.api;
 import org.signal.core.models.ServiceId;
 import org.signal.core.models.ServiceId.PNI;
 import org.signal.core.util.Base64;
+import org.signal.core.util.ProtoUtil;
 import org.signal.core.util.UuidUtil;
 import org.signal.libsignal.metadata.certificate.SenderCertificate;
 import org.signal.libsignal.protocol.IdentityKey;
@@ -2981,6 +2982,7 @@ public class SignalServiceMessageSender {
       } else {
         message = buildContentTooLargeBreadcrumbs(content.getContent().get());
       }
+      Log.w(TAG, "About to crash for exceeding max envelope size (" + size + " > " + maxEnvelopeSize + ")\n" + message);
       throw new ContentTooLargeException(size, message);
     }
   }
@@ -2996,104 +2998,7 @@ public class SignalServiceMessageSender {
   }
 
   private String buildContentTooLargeBreadcrumbs(Content content) {
-    StringBuilder message = new StringBuilder();
-
-    if (content.dataMessage != null) {
-      message.append("Data message;");
-      if (content.dataMessage.body != null && !content.dataMessage.body.isEmpty()) {
-        message.append("Body(").append(content.dataMessage.body.length()).append(");");
-      }
-      if (content.dataMessage.groupV2 != null) {
-        if (content.dataMessage.groupV2.groupChange != null) {
-          message.append("GroupV2Change(").append(content.dataMessage.groupV2.groupChange.size()).append(");");
-        } else {
-          message.append("GroupV2NoChange;");
-        }
-      }
-      if (content.dataMessage.giftBadge != null) {
-        message.append("GiftBadge;");
-      }
-      if (content.dataMessage.pollCreate != null) {
-        message.append("PollCreate;");
-      }
-      if (content.dataMessage.pollTerminate != null) {
-        message.append("PollTerminate;");
-      }
-      if (content.dataMessage.pollVote != null) {
-        message.append("PollVote;");
-      }
-      if (content.dataMessage.pinMessage != null) {
-        message.append("PinMessage;");
-      }
-      if (content.dataMessage.unpinMessage != null) {
-        message.append("UnpinMessage;");
-      }
-      if (content.dataMessage.reaction != null) {
-        message.append("Reaction;");
-      }
-      if (content.dataMessage.profileKey != null && content.dataMessage.profileKey.size() > 0) {
-        message.append("ProfileKey(").append(content.dataMessage.profileKey.size()).append(");");
-      }
-      if (content.dataMessage.payment != null) {
-        message.append("Payment;");
-      }
-      if (!content.dataMessage.attachments.isEmpty()) {
-        message.append("Attachments(").append(content.dataMessage.attachments.size()).append(");");
-      }
-      if (!content.dataMessage.contact.isEmpty()) {
-        message.append("Contacts(").append(content.dataMessage.contact.size()).append(");");
-      }
-      if (!content.dataMessage.bodyRanges.isEmpty()) {
-        message.append("Ranges(").append(content.dataMessage.bodyRanges.size()).append(");");
-      }
-      if (content.dataMessage.quote != null) {
-        if (content.dataMessage.quote.text != null) {
-          message.append("Quote(").append(content.dataMessage.quote.text.length()).append(");");
-        } else {
-          message.append("Quote(No text);");
-        }
-      }
-    }
-
-    if (content.syncMessage != null) {
-      message.append("Sync message;");
-
-      if (content.syncMessage.sent != null) {
-        if (content.syncMessage.sent.storyMessage != null) {
-          message.append("StoryMessage(").append(content.syncMessage.sent.storyMessageRecipients.size()).append(");");
-        }
-        if (!content.syncMessage.sent.storyMessageRecipients.isEmpty()) {
-          message.append("StoryRecipients(").append(content.syncMessage.sent.storyMessageRecipients.size()).append(");");
-        }
-        if (content.syncMessage.blocked != null) {
-          message.append("Blocked-AciString(").append(content.syncMessage.blocked.acis.size()).append(");");
-          message.append("Blocked-AciBinary(").append(content.syncMessage.blocked.acisBinary.size()).append(");");
-          message.append("Blocked-GroupIds(").append(content.syncMessage.blocked.groupIds.size()).append(");");
-          message.append("Blocked-Numbers(").append(content.syncMessage.blocked.numbers.size()).append(");");
-        }
-        if (content.syncMessage.outgoingPayment != null) {
-          message.append("OutgoingPayment");
-        }
-        if (content.syncMessage.deleteForMe != null) {
-          message.append("DeleteForMe-Messages(").append(content.syncMessage.deleteForMe.messageDeletes.size()).append(");");
-          message.append("DeleteForMe-Attachments(").append(content.syncMessage.deleteForMe.attachmentDeletes.size()).append(");");
-          message.append("DeleteForMe-Conversations(").append(content.syncMessage.deleteForMe.conversationDeletes.size()).append(");");
-        }
-        if (!content.syncMessage.read.isEmpty()) {
-          message.append("Read(").append(content.syncMessage.read.size()).append(");");
-        }
-        if (!content.syncMessage.viewed.isEmpty()) {
-          message.append("Viewed(").append(content.syncMessage.read.size()).append(");");
-        }
-      }
-    }
-
-    if (content.receiptMessage != null) {
-      message.append("ReceiptMessage(").append(content.receiptMessage.timestamp.size()).append(");");
-      message.append("ReceiptMessage(").append(content.receiptMessage.type.getValue()).append(");");
-    }
-
-    return message.toString();
+    return ProtoUtil.buildSizeTree(content, "Content");
   }
 
   public interface EventListener {

lib/libsignal-service/src/test/java/org/signal/core/util/BuildSizeTreeTest.kt

@@ -0,0 +1,154 @@
+/*
+ * Copyright 2025 Signal Messenger, LLC
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+
+package org.signal.core.util
+
+import assertk.assertThat
+import assertk.assertions.contains
+import assertk.assertions.doesNotContain
+import assertk.assertions.isEqualTo
+import assertk.assertions.startsWith
+import okio.ByteString.Companion.toByteString
+import org.junit.Test
+import org.whispersystems.signalservice.internal.push.BodyRange
+import org.whispersystems.signalservice.internal.push.Content
+import org.whispersystems.signalservice.internal.push.DataMessage
+import org.whispersystems.signalservice.internal.push.GroupContextV2
+import org.whispersystems.signalservice.internal.push.SyncMessage
+
+class BuildSizeTreeTest {
+
+  @Test
+  fun `empty message has zero encoded size`() {
+    val msg = DataMessage()
+    val tree = msg.buildSizeTree("DataMessage")
+    assertThat(tree).isEqualTo("DataMessage(0)")
+  }
+
+  @Test
+  fun `string field shows utf8 byte size`() {
+    val msg = DataMessage(body = "hello")
+    val tree = msg.buildSizeTree("DataMessage")
+
+    assertThat(tree).startsWith("DataMessage(")
+    assertThat(tree).contains("\n  body(5)")
+  }
+
+  @Test
+  fun `multi-byte utf8 string shows correct byte size`() {
+    val msg = DataMessage(body = "\uD83D\uDE00") // emoji, 4 bytes in UTF-8
+    val tree = msg.buildSizeTree("DataMessage")
+
+    assertThat(tree).contains("body(4)")
+  }
+
+  @Test
+  fun `ByteString field shows raw byte size`() {
+    val bytes = ByteArray(100).toByteString()
+    val msg = DataMessage(profileKey = bytes)
+    val tree = msg.buildSizeTree("DataMessage")
+
+    assertThat(tree).contains("\n  profileKey(100)")
+  }
+
+  @Test
+  fun `null and empty fields are omitted`() {
+    val msg = DataMessage(body = "hi")
+    val tree = msg.buildSizeTree("DataMessage")
+
+    assertThat(tree).doesNotContain("profileKey")
+    assertThat(tree).doesNotContain("groupV2")
+    assertThat(tree).doesNotContain("attachments")
+    assertThat(tree).doesNotContain("bodyRanges")
+  }
+
+  @Test
+  fun `nested message field shows indented sub-tree`() {
+    val msg = Content(
+      dataMessage = DataMessage(body = "test")
+    )
+    val tree = msg.buildSizeTree("Content")
+
+    assertThat(tree).startsWith("Content(")
+    assertThat(tree).contains("\n  dataMessage(")
+    assertThat(tree).contains("\n    body(4)")
+  }
+
+  @Test
+  fun `repeated message field shows count and total size with elements`() {
+    val ranges = listOf(
+      BodyRange(start = 0, length = 5),
+      BodyRange(start = 10, length = 3)
+    )
+    val msg = DataMessage(bodyRanges = ranges)
+    val tree = msg.buildSizeTree("DataMessage")
+
+    assertThat(tree).contains("bodyRanges[2](")
+    assertThat(tree).contains("bodyRanges[0](")
+    assertThat(tree).contains("bodyRanges[1](")
+  }
+
+  @Test
+  fun `deeply nested structure shows correct indentation`() {
+    val groupChange = ByteArray(50).toByteString()
+    val masterKey = ByteArray(32).toByteString()
+    val msg = Content(
+      dataMessage = DataMessage(
+        body = "hi",
+        groupV2 = GroupContextV2(
+          masterKey = masterKey,
+          groupChange = groupChange,
+          revision = 5
+        )
+      )
+    )
+    val tree = msg.buildSizeTree("Content")
+
+    // depth 0
+    assertThat(tree).startsWith("Content(")
+    // depth 1
+    assertThat(tree).contains("\n  dataMessage(")
+    // depth 2
+    assertThat(tree).contains("\n    body(2)")
+    assertThat(tree).contains("\n    groupV2(")
+    // depth 3
+    assertThat(tree).contains("\n      masterKey(32)")
+    assertThat(tree).contains("\n      groupChange(50)")
+  }
+
+  @Test
+  fun `encoded sizes match wire adapter`() {
+    val msg = Content(
+      dataMessage = DataMessage(body = "hello world")
+    )
+    val tree = msg.buildSizeTree("Content")
+
+    val contentSize = Content.ADAPTER.encodedSize(msg)
+    val dataMessageSize = DataMessage.ADAPTER.encodedSize(msg.dataMessage!!)
+
+    assertThat(tree).startsWith("Content($contentSize)")
+    assertThat(tree).contains("\n  dataMessage($dataMessageSize)")
+  }
+
+  @Test
+  fun `multiple top-level fields are all included`() {
+    val msg = Content(
+      dataMessage = DataMessage(body = "hi"),
+      syncMessage = SyncMessage()
+    )
+    val tree = msg.buildSizeTree("Content")
+
+    assertThat(tree).contains("dataMessage(")
+    assertThat(tree).contains("syncMessage(")
+  }
+
+  @Test
+  fun `custom root name is used`() {
+    val msg = DataMessage(body = "x")
+    val tree = msg.buildSizeTree("MyCustomName")
+
+    assertThat(tree).startsWith("MyCustomName(")
+  }
+}