Add WhatsApp contacts module and fix InteractionC contact resolution (#882)

* Add WhatsappContacts module to extract WhatsApp disappearing messages state

WhatsApp on iOS stores the disappearing messages timer for 1:1 chats on
the contact records in ContactsV2.sqlite, not in ChatStorage.sqlite. Add
a new WhatsappContacts module which extracts contact records from this
database, including phone numbers, WhatsApp and LID identifiers, and the
per-contact disappearing messages duration, and emits a timeline event
when a disappearing messages timer was set.

The database is often missing from incremental backups, so the module
logs a clear warning and returns no results instead of failing. Columns
are selected based on the actual table schema to tolerate changes across
WhatsApp versions, and if the disappearing messages column is absent the
state is reported as unknown rather than off.

The test fixture is a synthetic ContactsV2.sqlite with fictional
contacts, stored under the backup file ID derived from the WhatsApp
shared app group domain.

* Fix InteractionC contact resolution and resolve WhatsApp LIDs to contacts

The two primary InteractionC queries contained a SQL syntax error in
their direction CASE expression (a double column alias), so they always
failed and the module silently fell back to a reduced query without the
recipient join. As a result outgoing messages were serialized with no
counterpart at all ("from None (None)"). Fix the syntax so recipient
names and identifiers are extracted again, and normalize the raw 0/1
direction values from the fallback queries to INCOMING/OUTGOING.

WhatsApp identifies chat peers in interactionC.db by LID and stores the
peer LID in the domain identifier, which InteractionC could not map to a
person. Declare a dependency on the WhatsappContacts module and resolve
sender, recipient and domain identifiers (LID, JID or phone number)
against the WhatsApp contacts database, adding resolved phone number and
name fields to WhatsApp records.

Rewrite the timeline serialization to use the resolved values, fall back
to the chat peer from the domain identifier when no recipient was
recorded, label the local user instead of printing None, and include the
message direction and group name.

* Add timeline events for all WhatsApp contact timestamps

Extract ZABOUTEXPIRATIONTIMESTAMP and emit a timeline event for each
timestamp stored on a WhatsApp contact record: disappearing messages
timer changes, "about" text changes and scheduled expiry, and contact
record updates. ContactsV2.sqlite stores no other date attributes in
any released schema version.

* Add first and last interaction timeline events for WhatsApp chats

Extract one record per ZWACHATSESSION with the first and last stored
message dates, the session's own last-message date, the group creation
date and message counts. Each chat produces chat_first_message and
chat_last_message timeline events, and groups a group_created event.
The session last-message date is preferred over the newest stored
message because it survives message deletion.

* Resolve WhatsApp LID chat identifiers via the LID pair table

Recent WhatsApp versions key 1:1 chat sessions by an opaque LID rather
than the contact's phone number. Extract the ZWAPHONENUMBERLIDPAIR
table from the dedicated LID.sqlite database (or from ChatStorage
itself in versions that store it there) and use it to populate
partner_resolved_phone_number on chat session records and in timeline
events, without requiring the often-missing ContactsV2.sqlite. Each
pair is also extracted as a record and produces a lid_pair_recorded
timeline event marking when the association was learned.

* Reduce duplicate InteractionC timeline events

The interaction record's creation date normally trails its start date
by milliseconds, so serializing both nearly doubled the timeline with
duplicate entries. Only emit the creation date when it diverges from
the start date by more than an hour, with explicit wording, since a
record created long after its event indicates backfill by sync,
restore or tampering.

Per-contact aggregate dates from ZCONTACTS repeat on every interaction
row of the same contact and carried that row's message text. Serialize
them with contact-centric data strings instead, so timeline
de-duplication collapses them into one first/last-seen event per
contact.

tests/ios_backup/test_interactionc.py

@@ -0,0 +1,105 @@
+# Mobile Verification Toolkit (MVT)
+# Copyright (c) 2021-2026 The MVT Authors.
+# Use of this software is governed by the MVT License 1.1 that can be found at
+#   https://license.mvt.re/1.1/
+
+from mvt.common.module import run_module
+from mvt.ios.modules.mixed.interactionc import InteractionC
+from mvt.ios.modules.mixed.whatsapp_contacts import WhatsappContacts
+
+from ..utils import get_ios_backup_folder
+
+
+class TestInteractionCModule:
+    def test_extraction_with_whatsapp_contacts(self):
+        contacts = WhatsappContacts(target_path=get_ios_backup_folder())
+        run_module(contacts)
+
+        m = InteractionC(target_path=get_ios_backup_folder())
+        m.dependency_modules = {WhatsappContacts: contacts}
+        run_module(m)
+
+        assert len(m.results) == 3
+
+        incoming = next(
+            r for r in m.results if r["sender_identifier"] == "100000000000001@lid"
+        )
+        assert incoming["direction"] == "INCOMING"
+        assert incoming["sender_resolved_phone_number"] == "+14155550100"
+        assert incoming["sender_resolved_name"] == "Alice Example"
+
+        outgoing = next(
+            r for r in m.results if r["direction"] == "OUTGOING"
+        )
+        assert outgoing["recipient_identifier"] == "+14155550100"
+        assert outgoing["recipient_resolved_name"] == "Alice Example"
+        assert outgoing["domain_resolved_phone_number"] == "+14155550100"
+        assert outgoing["domain_resolved_name"] == "Alice Example"
+
+        sms = next(
+            r for r in m.results if r["bundle_id"] == "com.apple.MobileSMS"
+        )
+        assert sms.get("sender_resolved_name") is None
+        assert sms["sender_display_name"] == "Bob Example"
+
+        events = [entry["data"] for entry in m.timeline]
+        assert (
+            "[net.whatsapp.WhatsApp] INCOMING from "
+            "Alice Example (+14155550100) to local user" in events
+        )
+        assert (
+            "[net.whatsapp.WhatsApp] OUTGOING from local user to "
+            "Alice Example (+14155550100)" in events
+        )
+        assert (
+            "[com.apple.MobileSMS] INCOMING from "
+            "Bob Example (+14155550101) to local user" in events
+        )
+
+        # The creation date is only serialized when it diverges from the
+        # start date; the SMS record was created 90 days after the event.
+        creation_events = [
+            entry
+            for entry in m.timeline
+            if entry["event"] == "interactions_creation_date"
+        ]
+        assert len(creation_events) == 1
+        assert creation_events[0]["timestamp"] == "2025-12-09 12:26:40.000000"
+        assert creation_events[0]["data"] == (
+            "Interaction record created 90 days after the event: "
+            "[com.apple.MobileSMS] INCOMING from "
+            "Bob Example (+14155550101) to local user"
+        )
+
+        # Per-contact aggregate dates use contact-centric data strings.
+        first_seen = [
+            entry
+            for entry in m.timeline
+            if entry["event"] == "first_incoming_sender_date"
+        ]
+        assert len(first_seen) == 1
+        assert first_seen[0]["timestamp"] == "2025-09-03 13:46:40.000000"
+        assert first_seen[0]["data"] == (
+            "First incoming interaction from Bob Example (+14155550101)"
+        )
+        assert (
+            "Last incoming interaction from Bob Example (+14155550101)"
+            in events
+        )
+
+    def test_extraction_without_whatsapp_contacts(self):
+        # Without the WhatsappContacts dependency the module still runs, and
+        # unresolvable LIDs are shown as-is.
+        m = InteractionC(target_path=get_ios_backup_folder())
+        run_module(m)
+
+        assert len(m.results) == 3
+        events = [entry["data"] for entry in m.timeline]
+        assert (
+            "[net.whatsapp.WhatsApp] INCOMING from "
+            "100000000000001@lid to local user" in events
+        )
+        assert (
+            "[net.whatsapp.WhatsApp] OUTGOING from local user to "
+            "+14155550100" in events
+        )

tests/ios_backup/test_whatsapp.py

@@ -6,8 +6,79 @@
 import logging
 
 from mvt.common.indicators import Indicators
+from mvt.common.module import run_module
 from mvt.ios.modules.mixed.whatsapp import Whatsapp
 
+from ..utils import get_ios_backup_folder
+
+
+def test_extraction():
+    m = Whatsapp(target_path=get_ios_backup_folder())
+    run_module(m)
+
+    messages = [r for r in m.results if "ZTEXT" in r]
+    sessions = [r for r in m.results if r.get("record_type") == "chat_session"]
+    pairs = [
+        r for r in m.results
+        if r.get("record_type") == "lid_phone_number_pair"
+    ]
+    assert len(messages) == 3
+    assert len(sessions) == 2
+    assert len(pairs) == 1
+
+    assert pairs[0]["lid"] == "100000000000001"
+    assert pairs[0]["phone_number"] == "14155550100"
+    assert pairs[0]["pair_timestamp"] == "2025-08-25 07:33:20.000000"
+
+    linked = next(r for r in messages if r.get("links"))
+    assert linked["links"] == ["https://example.org/news"]
+
+    alice = next(s for s in sessions if s["partner_name"] == "Alice Example")
+    assert alice["contact_jid"] == "100000000000001@lid"
+    assert alice["partner_resolved_phone_number"] == "+14155550100"
+    assert alice["first_stored_message_date"] == "2025-08-27 15:06:40.000000"
+    assert alice["last_message_date"] == "2025-08-28 18:53:20.000000"
+    assert alice["group_creation_date"] is None
+    assert alice["stored_message_count"] == 2
+
+    group = next(s for s in sessions if s["partner_name"] == "Example Group")
+    assert group["group_creation_date"] == "2025-08-21 20:13:20.000000"
+    assert group["first_stored_message_date"] == "2025-08-29 22:40:00.000000"
+    # The last stored message predates the session's own last-message date:
+    # the newest message in this chat was deleted.
+    assert group["last_stored_message_date"] == "2025-08-29 22:40:00.000000"
+    assert group["last_message_date"] == "2025-08-31 02:26:40.000000"
+
+    # 3 message events, first/last per chat, the group creation and the
+    # LID-phone number pair.
+    assert len(m.timeline) == 9
+    events = {
+        (entry["event"], entry["timestamp"]): entry["data"]
+        for entry in m.timeline
+    }
+    # Alice's session is keyed by LID but labelled with the phone number
+    # resolved through LID.sqlite.
+    assert events[("chat_first_message", "2025-08-27 15:06:40.000000")] == (
+        "First stored message in WhatsApp chat with "
+        "'Alice Example' (+14155550100)"
+    )
+    assert events[("chat_last_message", "2025-08-28 18:53:20.000000")] == (
+        "Last message in WhatsApp chat with "
+        "'Alice Example' (+14155550100)"
+    )
+    assert events[("lid_pair_recorded", "2025-08-25 07:33:20.000000")] == (
+        "WhatsApp associated LID 100000000000001 with "
+        "phone number 14155550100"
+    )
+    assert events[("group_created", "2025-08-21 20:13:20.000000")] == (
+        "WhatsApp group chat 'Example Group' "
+        "(120000000000000001@g.us) was created"
+    )
+    assert ("chat_first_message", "2025-08-29 22:40:00.000000") in events
+    assert ("chat_last_message", "2025-08-31 02:26:40.000000") in events
+
+    assert len(m.alertstore.alerts) == 0
+
 
 def test_collect_url_results_includes_expansion():
     module = Whatsapp(

tests/ios_backup/test_whatsapp_contacts.py

@@ -0,0 +1,83 @@
+# Mobile Verification Toolkit (MVT)
+# Copyright (c) 2021-2026 The MVT Authors.
+# Use of this software is governed by the MVT License 1.1 that can be found at
+#   https://license.mvt.re/1.1/
+
+from mvt.common.module import run_module
+from mvt.ios.modules.mixed.whatsapp_contacts import WhatsappContacts
+
+from ..utils import get_ios_backup_folder
+
+
+class TestWhatsappContactsModule:
+    def test_extraction(self):
+        m = WhatsappContacts(target_path=get_ios_backup_folder())
+        run_module(m)
+        assert len(m.results) == 2
+
+        alice = next(r for r in m.results if r["given_name"] == "Alice")
+        assert alice["full_name"] == "Alice Example"
+        assert alice["phone_number"] == "+14155550100"
+        assert alice["whatsapp_id"] == "14155550100@s.whatsapp.net"
+        assert alice["lid"] == "100000000000001@lid"
+        assert alice["user_name"] == "alice.example"
+        assert alice["disappearing_mode_duration"] == 86400.0
+        assert alice["disappearing_mode_is_on"] is True
+        assert alice["disappearing_mode_label"] == "24 hours"
+        assert alice["disappearing_mode_timestamp"] == "2025-07-23 21:46:40.000000"
+        assert alice["about_timestamp"] == "2025-07-12 08:00:00.000000"
+        assert alice["about_expiration_timestamp"] == "2025-08-16 01:20:00.000000"
+        assert alice["last_updated"] == "2025-08-04 11:33:20.000000"
+
+        bob = next(r for r in m.results if r["given_name"] == "Bob")
+        assert bob["lid"] is None
+        assert bob["disappearing_mode_duration"] is None
+        assert bob["disappearing_mode_is_on"] is False
+        assert bob["disappearing_mode_label"] == "off"
+        assert bob["disappearing_mode_timestamp"] is None
+
+        # Alice: disappearing_mode_set, about_changed, about_expiration and
+        # contact_last_updated. Bob: contact_last_updated only.
+        assert len(m.timeline) == 5
+
+        events = {
+            (entry["event"], entry["timestamp"]): entry["data"]
+            for entry in m.timeline
+        }
+        assert (
+            "24 hours"
+            in events[("disappearing_mode_set", "2025-07-23 21:46:40.000000")]
+        )
+        assert (
+            "14155550100@s.whatsapp.net (Alice Example)"
+            in events[("disappearing_mode_set", "2025-07-23 21:46:40.000000")]
+        )
+        assert (
+            'changed to "Hey there! I am using WhatsApp."'
+            in events[("about_changed", "2025-07-12 08:00:00.000000")]
+        )
+        assert (
+            "scheduled to expire"
+            in events[("about_expiration", "2025-08-16 01:20:00.000000")]
+        )
+
+        updated = [
+            entry["data"]
+            for entry in m.timeline
+            if entry["event"] == "contact_last_updated"
+        ]
+        assert len(updated) == 2
+        assert all(
+            entry["timestamp"] == "2025-08-04 11:33:20.000000"
+            for entry in m.timeline
+            if entry["event"] == "contact_last_updated"
+        )
+        assert any("14155550101@s.whatsapp.net (Bob Example)" in d for d in updated)
+
+        assert len(m.alertstore.alerts) == 0
+
+    def test_missing_database(self, tmp_path):
+        m = WhatsappContacts(target_path=str(tmp_path))
+        run_module(m)
+        assert m.results == []
+        assert len(m.alertstore.alerts) == 0

tests/ios_fs/test_filesystem.py

@@ -15,8 +15,8 @@ class TestFilesystem:
     def test_filesystem(self):
         m = Filesystem(target_path=get_ios_backup_folder())
         run_module(m)
-        assert len(m.results) == 15
-        assert len(m.timeline) == 15
+        assert len(m.results) == 23
+        assert len(m.timeline) == 23
         assert len(m.alertstore.alerts) == 0
 
     def test_detection(self, indicator_file):
@@ -29,6 +29,6 @@ class TestFilesystem:
         )
         m.indicators = ind
         run_module(m)
-        assert len(m.results) == 15
-        assert len(m.timeline) == 15
+        assert len(m.results) == 23
+        assert len(m.timeline) == 23
         assert len(m.alertstore.alerts) == 1