Attribute non-SFI READ/UPDATE to the selected file even without a content decoder

mobileid_activate_setpin_resetpin_20201222 regression: UPDATE BINARY
(plain offset addressing) after an SMS-PP DOWNLOAD / proactive group
showed "Writes: —" in the map view, although selection tracking kept
EF_SMSS selected the whole time.

Root cause: the sel-based branch only emitted result['file'] when
_decode_file_data() produced content — files without a registered
content decoder (EF_SMSS 6F43) silently lost attribution. The first
write only displayed via the frontend's SELECT-note fallback, which
masked the bug until a proactive group split the RW run.

Fix: decouple attribution from content decoding in both the command
branch and the GET RESPONSE branch — when the selected file has no
content decoder (or the offset is non-zero, where content decode is
intentionally skipped), emit {fid, ef} so the map, list, and detail
views always name the file. Content decoders still take priority.

Session 63 now decodes all three UPDATE BINARY ops as ADF/EF_SMSS.
Tests: +4 TestFileAttribution, one expectation updated to the new
contract — 342 total. Version 1.16.1, SW cache v23.

frontend/index.html

@@ -1881,7 +1881,7 @@ function onFilterChange() {
 }
 
 // ──────────────────── Versioning ────────────────────
-const PWA_VERSION = '1.16.0';
+const PWA_VERSION = '1.16.1';
 const MIN_SERVER_VERSION = '1.0.0';
 
 function parseVersion(v) {

frontend/sw.js

@@ -1,4 +1,4 @@
-const CACHE = 'simtrace-analyser-v22';
+const CACHE = 'simtrace-analyser-v23';
 
 const PRECACHE = [
     'index.html',

pyproject.toml

@@ -4,7 +4,7 @@ build-backend = "setuptools.backends._legacy:_Backend"
 
 [project]
 name = "simtrace2-pysniff"
-version = "1.16.0"
+version = "1.16.1"
 description = "Python-based sniffing tool for SIMtrace2 hardware (SIM card communication sniffer)"
 readme = {file = "README.md", content-type = "text/markdown"}
 license = {text = "GPL-2.0-or-later"}

simtrace2_pysniff/__init__.py

@@ -6,7 +6,7 @@ from .gsmtap import GsmtapSender, GsmtapReceiver
 from .pcap import PcapWriter
 from .dump import FileDumper, format_message
 
-__version__ = '1.16.0'
+__version__ = '1.16.1'
 __all__ = [
     'SniffSession',
     'DeviceDisconnected',

simtrace2_pysniff/server/decode.py

@@ -3858,13 +3858,22 @@ def decode_message(raw_data, prev=None):
                 result['file'] = {'sfi': rec_sfi, 'unknown': True, 'ef': f'SFI {rec_sfi}'}
         elif ins in (0xB0, 0xB2, 0xD6, 0xDC) and prev and prev.get('sel'):
             offset = p1p2.get('offset', 0)
-            if ins in (0xB2, 0xDC) or offset == 0:
             if ins in (0xB2, 0xDC) and not _is_record_file(prev['sel']):
                 result['file'] = _stale_file_note(prev['sel'])
             else:
+                file_dec = None
+                if ins in (0xB2, 0xDC) or offset == 0:
                     file_dec = _decode_file_data(prev['sel']['fid'], body, p1=p1)
                 if file_dec:
                     result['file'] = file_dec
+                else:
+                    # Known file, no content decoder (or non-zero offset) —
+                    # still attribute the operation to the selected file.
+                    result['file'] = {
+                        'fid': prev['sel']['fid'],
+                        'ef': KNOWN_FIDS.get(prev['sel']['fid'],
+                                             prev['sel']['fid'].upper()),
+                    }
 
     # SW
     if sw_bytes:
@@ -3884,6 +3893,13 @@ def decode_message(raw_data, prev=None):
                         file_dec = _decode_file_data(prev['sel']['fid'], remaining[:cmd_body_len])
                         if file_dec:
                             result['file'] = file_dec
+                        else:
+                            # Known file, no content decoder — attribute anyway.
+                            fid = prev['sel']['fid']
+                            result['file'] = {
+                                'fid': fid,
+                                'ef': KNOWN_FIDS.get(fid, fid.upper()),
+                            }
                 elif prev_ins == 0xA2 and prev.get('sel') and prev.get('file_ok'):
                     if not _is_record_file(prev['sel']):
                         result['file'] = _stale_file_note(prev['sel'])

tests/test_decode.py

@@ -1143,10 +1143,13 @@ class TestFileDecoders(unittest.TestCase):
         self.assertIn('IMSI 250011234567890', r['summary'])
 
     def test_read_binary_offset_skip(self):
+        # Non-zero offset: content decode is skipped (data starts mid-file)
+        # but the operation is still attributed to the selected file.
         r = decode_message(bytes.fromhex('00b00100') +
                            bytes.fromhex('082905102143658709') + bytes.fromhex('9000'),
                            prev={'sel': {'fid': '6f07'}})
-        self.assertNotIn('file', r)
+        self.assertEqual(r['file'], {'fid': '6f07', 'ef': 'EF_IMSI'})
+        self.assertNotIn('imsi', r['file'])
 
     def test_read_binary_offset_form(self):
         # b8 of P1 = 0 → offset = b7..b1 << 8 | P2.
@@ -2129,6 +2132,47 @@ class TestApduSpecCoverage(unittest.TestCase):
         self.assertEqual(r, 'MANAGE LSI')
 
 
+class TestFileAttribution(unittest.TestCase):
+    """Non-SFI READ/UPDATE attribute to the last file selected in the
+    channel — even when the file has no content decoder (mobileid
+    session 63 regression: UPDATE BINARY after a proactive group)."""
+
+    SEL_SMSS = {'sel': {'fid': '6f43', 'name': 'EF_SMSS', 'structure': 'transparent'}}
+
+    def _upd(self, prev):
+        raw = bytes.fromhex('00d6000004aabbccdd' + '9000')
+        return decode_message(raw, prev=prev)
+
+    def test_update_atributed_without_content_decoder(self):
+        # EF_SMSS (6F43) has no FILE_DECODERS entry — attribution must
+        # still carry the file name.
+        r = self._upd(dict(self.SEL_SMSS, ins=0xB0, ins_name='SELECT', sw1='61'))
+        self.assertEqual(r['file'], {'fid': '6f43', 'ef': 'EF_SMSS'})
+
+    def test_update_with_content_decoder_wins(self):
+        prev = dict(self.SEL_SMSS, ins=0xB0, ins_name='SELECT', sw1='61')
+        prev['sel'] = {'fid': '6f7e', 'name': 'EF_LOCI', 'structure': 'transparent'}
+        raw = bytes.fromhex('00d600000b' + '00' * 11 + '9000')
+        r = decode_message(raw, prev=prev)
+        self.assertEqual(r['file']['ef'], 'EF_LOCI')
+        self.assertIn('mcc', r['file'])
+
+    def test_update_nonzero_offset_attributed(self):
+        # Content decode skipped for non-zero offset, attribution kept.
+        raw = bytes.fromhex('00d6001004aabbccdd' + '9000')
+        r = decode_message(raw, prev=dict(self.SEL_SMSS, ins=0xB0,
+                                          ins_name='SELECT', sw1='61'))
+        self.assertEqual(r['file']['ef'], 'EF_SMSS')
+
+    def test_get_response_attribution(self):
+        # READ BINARY (61 XX) → GET RESPONSE on a decoder-less file
+        prev = dict(self.SEL_SMSS, ins=0xB0, ins_name='READ BINARY', sw1='61',
+                    file_ok=True)
+        raw = bytes.fromhex('00c0000002' + 'cafe' + '9000')
+        r = decode_message(raw, prev=prev)
+        self.assertEqual(r['file'], {'fid': '6f43', 'ef': 'EF_SMSS'})
+
+
 class TestClaDecode(unittest.TestCase):
     """ISO 7816-4 §5.1.1 first/further interindustry CLA coding."""
 

tests/test_pcap_import.py

@@ -197,7 +197,7 @@ class TestImportEndpoint(unittest.TestCase):
 class TestVersion(unittest.TestCase):
     def test_package_version(self):
         from simtrace2_pysniff import __version__
-        self.assertEqual(__version__, '1.16.0')
+        self.assertEqual(__version__, '1.16.1')
 
     def test_status_includes_version(self):
         import os