Files
simtrace-analyser/simtrace_analyser/filetrack.py
T
catarrh cad3999307 Files view: change details with before/after images (v2.4.0)
- the timeline's Δ glyph became a **Details** button, and it now appears on
  Update rows too (not just card-side changes); EN "Changed (card)" ->
  "Changed on card", RU "Изменено (картой)" -> "Изменено картой"
- the details modal shows the affected unit — the whole file, or the single
  record that changed — **before and after** the change as hex views (16 bytes
  per row, ASCII column, never-observed bytes as `--`), with the bytes that
  changed and the bytes the operation *first observed* highlighted in two
  different colours, plus the changed/new byte counts and the APDU reference;
  the old before/after byte table is gone
- `GET /api/sessions/<id>/files/image?key=…&change=…` returns those two views
  (segments with offsets) plus the change's metadata; the images are
  reconstructed from the current image by undoing the later changes
  (`FileTracker.change_images`), so nothing is duplicated per event — every
  value change is an event, hence the values are exact (a byte only first
  observed later can appear as known in both views)
- tracker: change events carry `observed_ranges` (bytes that were unknown
  before the operation) next to `ranges`; an update that only observes new
  bytes now records an event (so it can be inspected); record-file ranges are
  in-record byte offsets (the record number stays in its own field), which the
  previous "record number as position" could not express for a hex highlight
- tests: change-images reconstruction (before/after per event, later changes
  undone, records isolated, observation-only events, unknown gaps), the image
  endpoint (200/404/400), and Node tests for the hex-image helper (highlight
  classes, unknown gaps, ASCII, row limit) and the modal rendering
- v2.4.0; SW cache simtrace-analyser-v65
2026-10-17 21:19:14 +03:00

589 lines
23 KiB
Python

"""Per-file tracking over a recorded session (the Files view's data model).
Unlike the per-channel selection state in ``database.py`` — which only answers
"what is selected right now" and is wiped by every reset — this tracker keeps a
**trace-wide registry keyed by (DF, FID)**: access counters, a sparse image of
the observed contents, and the change log. It is built in a single pass over
the session's decoded messages (``Database.track_files``).
What is tracked
---------------
* **Counters** ``select``/``read``/``update``, successful operations only
(``database._SUCCESS_SW1``), unaffected by card resets.
* **Image** — the bytes we believe the file holds: reads and updates both fill
it (transparent files by offset, record files by record number). Only
*observed* bytes exist; never-read regions stay unknown.
* **Changes**
- *device* — an UPDATE (D6/DC) that modified bytes we already knew, applied
to the image and logged at its own APDU (``no_change`` flags a provable
no-op: every written byte was known and identical);
- *card* — a READ whose bytes differ from the image **on bytes we already
knew**; logged at the read that surfaced it, with the changed ranges and
the before/after bytes for the UI's diff. Bytes we never saw just fill the
image (an observation, not a change).
Registration happens on a successful SELECT **or** on any successfully
attributed read/update — including SFI-addressed operations. SFI → FID
relations come from the normative table (``decode._SFI_BY_DF``) and from every
surfaced FCI (the FCP's ``88`` tag); an SFI access that precedes its relation
gets a provisional ``(DF, 'SFI:n')`` entry which is merged into the resolved
``(DF, FID)`` entry when the relation is learned (counters, image and change
log move over — one file, one image, one change log, whatever the access
path).
Bounds: at most ``IMAGE_CAP`` observed bytes per file (the file is frozen
afterwards — comparing against a partial image would produce fake card-change
signals) and at most ``EVENTS_CAP`` change events per file (``changes_total``
keeps counting).
"""
from .database import _SUCCESS_SW1
from .decode import (_is_df_fid, select_target_fid, selected_df_fid, sfi_table)
IMAGE_CAP = 64 * 1024 # observed bytes kept per file
EVENTS_CAP = 1000 # change events kept per file
_READ_INS = (0xB0, 0xB1, 0xB2) # binary/record reads (SEARCH RECORD is not
_UPDATE_INS = (0xD6, 0xDC) # a content read — it returns record numbers)
_GR_READ_FOR = ('READ BINARY', 'READ RECORD')
def _success(d):
"""True when the message's status word means success (incl. 61xx)."""
sw1 = (d.get('sw') or {}).get('sw1')
return sw1 in _SUCCESS_SW1
def _body_bytes(d):
return bytes.fromhex((d.get('body') or {}).get('hex') or '')
def _file_label(d):
"""The display name of an operation's file (same vocabulary as the Map
view: the EF name, the FID, or the SFI placeholder)."""
f = d.get('file') or {}
if f.get('ef'):
return f['ef']
if f.get('fid'):
return f['fid'].upper()
if f.get('sfi') is not None:
return f'SFI {f["sfi"]}'
return None
def _key_str(key):
df, fid = key
return f'{df}/{fid}'
def _parse_key(key):
df, _sep, fid = (key or '').rpartition('/')
return df, fid
def _apply_hex(buf, ranges, hex_str):
"""Write a concatenated hex string into *buf* at the given ranges."""
at = 0
for pos, length in ranges or []:
chunk = bytes.fromhex(hex_str[at:at + length * 2])
at += length * 2
if len(buf) < pos + length:
buf.extend(b'\x00' * (pos + length - len(buf)))
buf[pos:pos + length] = chunk
def _segments(buf, mask):
"""Observed runs of the image: ``[{'offset': n, 'hex': '…'}, …]``."""
out = []
i = 0
while i < len(mask):
if not mask[i]:
i += 1
continue
start = i
while i < len(mask) and mask[i]:
i += 1
out.append({'offset': start, 'hex': bytes(buf[start:i]).hex()})
return out
class _FileEntry:
"""One tracked file: counters, sparse image, change log."""
def __init__(self, key, df, fid, name, image_cap=IMAGE_CAP):
self.key = key
self.df = df
self.fid = fid
self.name = name
self.image_cap = image_cap
self.sfi = None
self.structure = None
self.size = None
self.record_len = None
self.n_records = None
self.counters = {'select': 0, 'read': 0, 'update': 0}
self.changes = []
self.changes_total = 0
self.image_truncated = False
# Observed contents: transparent files in one buffer indexed by the
# byte offset; record files per record number. The masks mark the
# bytes that came from an observation (everything else is unknown).
self.buf = bytearray()
self.mask = bytearray()
self.records = {}
self.rec_mask = {}
# -- image ----------------------------------------------------------
def _tracked_bytes(self):
return len(self.buf) + sum(len(r) for r in self.records.values())
def apply(self, record, offset, data):
"""Apply observed bytes.
Returns ``(diffs, observed, compared_all)``:
* *diffs* — ``[(pos, before, after)]`` for positions whose known value
differed (pos = the byte offset in the file, or *in the record* for
record files);
* *observed* — ``[(pos, len)]`` runs whose bytes were not known before
this operation (a first observation);
* *compared_all* — every written byte was already known (so an empty
diff proves a no-op).
"""
if self.image_truncated:
return [], [], False
if record is None:
buf, mask, base = self.buf, self.mask, offset
needed = base + len(data)
else:
buf = self.records.setdefault(record, bytearray())
mask = self.rec_mask.setdefault(record, bytearray())
base = 0
needed = len(data)
if (needed > len(buf)
and self._tracked_bytes() + (needed - len(buf)) > self.image_cap):
self.image_truncated = True
return [], [], False
if len(buf) < needed:
buf.extend(b'\x00' * (needed - len(buf)))
mask.extend(b'\x00' * (needed - len(mask)))
diffs = []
observed = []
compared_all = True
i = 0
while i < len(data):
pos = base + i
if not mask[pos]:
compared_all = False
start = pos
while i < len(data) and not mask[base + i]:
buf[base + i] = data[i]
mask[base + i] = 1
i += 1
observed.append((start, i - (start - base)))
continue
if buf[pos] == data[i]:
i += 1
continue
start = pos
before = bytearray()
after = bytearray()
while i < len(data) and mask[base + i] and buf[base + i] != data[i]:
before.append(buf[base + i])
after.append(data[i])
buf[base + i] = data[i]
i += 1
diffs.append((start, bytes(before), bytes(after)))
return diffs, observed, compared_all
def coverage(self):
known = sum(self.mask) + sum(sum(m) for m in self.rec_mask.values())
return {'known': known, 'observed': self._tracked_bytes(),
'size': self.size}
class FileTracker:
"""Builds the per-file registry from a session's decoded messages."""
def __init__(self, image_cap=IMAGE_CAP, events_cap=EVENTS_CAP):
self._image_cap = image_cap
self._events_cap = events_cap
self.files = {} # key -> _FileEntry
self.timeline = [] # one item per read/update/card change
self.sfi_relations = {} # df -> {sfi: fid}
self.aid_labels = {} # AID (upper hex) -> application label
self._index = 0
self._pending_read = {} # channel -> {'d', 'df'} read awaiting its data
# -- observation ----------------------------------------------------
def observe(self, msg, state, channel=0):
"""Observe one decoded message; *state* is the channel state before it."""
index = self._index
self._index += 1
d = msg.get('decoded')
if msg.get('type') != 'tpdu' or not d or not d.get('ins_hex'):
return
ins_hex = d['ins_hex']
df = state.get('df') or '3f00'
if ins_hex == 'c0':
self._observe_get_response(d, state, channel, index, msg)
return
self._pending_read.pop(channel, None)
ins = int(ins_hex, 16)
if ins == 0xA4:
self._observe_select(d, df)
elif ins in _UPDATE_INS:
self._observe_write(d, df, index, msg)
elif ins in _READ_INS:
self._observe_read(d, df, channel, index, msg)
# -- file registry ---------------------------------------------------
def _entry(self, df, fid, name=None):
key = (df, fid)
entry = self.files.get(key)
if entry is None:
entry = _FileEntry(key, df, fid,
name or (fid.upper() if fid else '?'),
image_cap=self._image_cap)
self.files[key] = entry
elif name:
placeholders = {entry.fid, entry.fid.upper(), '', '?'}
if entry.sfi is not None:
placeholders.add(f'SFI {entry.sfi}')
placeholders.add(f'SFI:{entry.sfi}')
if entry.name in placeholders:
entry.name = name
return entry
def _resolve_sfi(self, df, sfi):
rel = self.sfi_relations.get(df, {})
if sfi in rel:
return rel[sfi]
return sfi_table(df).get(sfi)
def _learn_sfi(self, df, sfi, fid, entry=None):
self.sfi_relations.setdefault(df, {})[sfi] = fid
if entry is not None:
entry.sfi = sfi
self._merge_provisional(df, sfi, fid)
def _file_ref(self, d, df):
"""(fid-or-provisional-key, sfi) for an operation's file."""
f = d.get('file') or {}
sfi = f.get('sfi')
if sfi is None:
sfi = (d.get('p1p2') or {}).get('sfi')
if sfi is None:
sfi = (d.get('p2') or {}).get('sfi')
fid = f.get('fid')
if fid:
return fid, sfi
if sfi is not None:
resolved = self._resolve_sfi(df, sfi)
if resolved:
self._learn_sfi(df, sfi, resolved)
return resolved, sfi
return f'SFI:{sfi}', sfi
return None, None
def _merge_provisional(self, df, sfi, fid):
"""Fold a provisional (df, 'SFI:n') entry into the resolved one."""
provisional = self.files.get((df, f'SFI:{sfi}'))
if provisional is None:
return
del self.files[(df, f'SFI:{sfi}')]
real = self.files.get((df, fid))
if real is None:
provisional.key = (df, fid)
provisional.fid = fid
provisional.sfi = sfi
self.files[(df, fid)] = provisional
target = provisional
else:
real.sfi = sfi
for kind in ('select', 'read', 'update'):
real.counters[kind] += provisional.counters[kind]
_merge_image(real, provisional)
real.changes = sorted(real.changes + provisional.changes,
key=lambda c: c['index'])
real.changes_total += provisional.changes_total
target = real
for item in self.timeline:
if item.get('entry') is provisional:
item['entry'] = target
item['file'] = self._file_json(target)
def _file_json(self, entry):
return {'key': _key_str(entry.key), 'name': entry.name,
'fid': entry.fid, 'df': entry.df, 'sfi': entry.sfi}
def _push(self, kind, entry, index, msg, **extra):
item = {'kind': kind, 'entry': entry, 'index': index,
'msg_id': msg.get('id'), 'elapsed': msg.get('elapsed'),
'file': self._file_json(entry)}
item.update(extra)
self.timeline.append(item)
return item
def _add_change(self, entry, kind, index, msg, op, diffs, observed=(),
record=None):
entry.changes_total += 1
if len(entry.changes) >= self._events_cap:
return None
event = {
'kind': kind, 'op': op, 'index': index, 'msg_id': msg.get('id'),
'elapsed': msg.get('elapsed'), 'record': record,
'ranges': [[pos, len(before)] for pos, before, _after in diffs],
'observed_ranges': [[pos, length] for pos, length in observed],
'before_hex': b''.join(b for _p, b, _a in diffs).hex(),
'after_hex': b''.join(a for _p, _b, a in diffs).hex(),
}
entry.changes.append(event)
return len(entry.changes) - 1
# -- operations ------------------------------------------------------
def _observe_select(self, d, df):
fid = select_target_fid(d)
if not fid or _is_df_fid(fid) or not _success(d):
return
# A path selection of an EF also enters the EF's parent DF
# (TS 102 221 §8.4.1) — key the file by that DF, not the one the
# channel was in before the SELECT.
effective = selected_df_fid(d, df) or df
self._entry(effective, fid).counters['select'] += 1
def _observe_get_response(self, d, state, channel, index, msg):
response = d.get('response') or {}
if d.get('response_for') == 'SELECT' and response:
# The FCP of the selected file: learn the SFI relation and the
# file facts (structure/size/records).
fid = (state.get('sel') or {}).get('fid')
if not fid or _is_df_fid(fid):
return
df = state.get('df') or '3f00'
entry = self._entry(df, fid)
fd = response.get('file_descriptor')
if isinstance(fd, dict):
entry.structure = fd.get('structure', entry.structure)
entry.record_len = fd.get('record_length', entry.record_len)
entry.n_records = fd.get('num_records', entry.n_records)
if response.get('file_size') is not None:
entry.size = response['file_size']
elif response.get('total_file_size') is not None:
entry.size = response['total_file_size']
if response.get('sfi') is not None:
self._learn_sfi(df, response['sfi'], fid, entry)
return
if d.get('response_for') in _GR_READ_FOR:
pending = self._pending_read.pop(channel, None)
# Prefer the data-bearing GET RESPONSE's own attribution; an
# SFI-addressed command keeps its context (the response's
# attribution resolves against the current selection, not the SFI).
src, src_df = d, state.get('df') or '3f00'
if pending:
_fid, sfi = self._file_ref(pending['d'], pending['df'])
if sfi is not None:
src, src_df = pending['d'], pending['df']
self._apply_read(src, src_df, index, msg, _body_bytes(d))
def _observe_read(self, d, df, channel, index, msg):
if not _success(d):
return
if not _body_bytes(d):
# Data pending (T=0): the GET RESPONSE will carry it.
self._pending_read[channel] = {'d': d, 'df': df}
return
self._apply_read(d, df, index, msg, _body_bytes(d))
def _apply_read(self, d, df, index, msg, data):
if not data:
return
fid, sfi = self._file_ref(d, df)
if fid is None:
return
entry = self._entry(df, fid, _file_label(d))
if sfi is not None and entry.sfi is None:
entry.sfi = sfi
entry.counters['read'] += 1
record = self._record_number(d)
diffs, observed, _compared = entry.apply(record, self._offset(d, record), data)
if entry.image_truncated:
return
if diffs:
idx = self._add_change(entry, 'card', index, msg,
d.get('ins_name') or '', diffs,
observed=observed, record=record)
self._push('card_change', entry, index, msg, record=record,
change_ref={'file': _key_str(entry.key), 'idx': idx}
if idx is not None else None)
else:
self._push('read', entry, index, msg, record=record)
self._note_dir_content(d)
def _observe_write(self, d, df, index, msg):
data = _body_bytes(d)
if not data or not _success(d):
return
fid, sfi = self._file_ref(d, df)
if fid is None:
return
entry = self._entry(df, fid, _file_label(d))
if sfi is not None and entry.sfi is None:
entry.sfi = sfi
entry.counters['update'] += 1
record = self._record_number(d)
diffs, observed, compared_all = entry.apply(record, self._offset(d, record), data)
if entry.image_truncated:
return
change_ref = None
if diffs or observed:
idx = self._add_change(entry, 'device', index, msg,
d.get('ins_name') or '', diffs,
observed=observed, record=record)
if idx is not None:
change_ref = {'file': _key_str(entry.key), 'idx': idx}
self._push('update', entry, index, msg, record=record, change_ref=change_ref,
no_change=(not diffs and compared_all))
# -- helpers ---------------------------------------------------------
def _offset(self, d, record):
if record is not None:
return 0
return (d.get('p1p2') or {}).get('offset', 0)
def _record_number(self, d):
if d.get('ins_hex') not in ('b2', 'dc'):
return None
raw = (d.get('p1') or {}).get('raw')
return int(raw, 16) if raw is not None else None
def _note_dir_content(self, d):
"""Harvest AID -> label pairs from a surfaced EF.DIR."""
apps = (d.get('file') or {}).get('applications')
if not apps:
return
for app in apps:
aid = (app.get('aid') or '').upper()
if aid and app.get('label'):
self.aid_labels[aid] = app['label']
# -- result ----------------------------------------------------------
def change_images(self, key, idx):
"""Before/after images of the unit affected by change *idx* of *key*.
The unit is the whole file for transparent files, the changed record
for record files. The images are reconstructed from the current image
by undoing the later events' changed bytes (every value change is an
event, so the values are exact; a byte that was only *first observed*
later can appear as known in both views). The requested event's own
``observed_ranges`` are shown as unknown in the *before* view — that is
what "newly observed" means.
"""
entry = self.files.get(_parse_key(key))
if entry is None or not 0 <= idx < len(entry.changes):
return None
event = entry.changes[idx]
record = event.get('record')
if record is None:
buf = bytearray(entry.buf)
mask = bytearray(entry.mask)
else:
buf = bytearray(entry.records.get(record, b''))
mask = bytearray(entry.rec_mask.get(record, b''))
for later in reversed(entry.changes[idx:]): # the event itself included
if later.get('record') != record:
continue
_apply_hex(buf, later['ranges'], later['before_hex'])
# The before view: this event's newly observed bytes were unknown then.
for pos, length in event.get('observed_ranges') or []:
for i in range(pos, min(pos + length, len(mask))):
mask[i] = 0
before = _segments(buf, mask)
# The after view: this event's changed bytes and its observations.
_apply_hex(buf, event['ranges'], event['after_hex'])
for pos, length in event.get('observed_ranges') or []:
for i in range(pos, min(pos + length, len(mask))):
mask[i] = 1
after = _segments(buf, mask)
return {
'key': _key_str(entry.key),
'name': entry.name,
'df': entry.df,
'fid': entry.fid,
'structure': entry.structure,
'size': entry.size,
'record_len': entry.record_len,
'n_records': entry.n_records,
'record': record,
'image_truncated': entry.image_truncated,
'coverage': entry.coverage(),
'kind': event['kind'],
'op': event['op'],
'index': event['index'],
'msg_id': event.get('msg_id'),
'elapsed': event.get('elapsed'),
'ranges': event['ranges'],
'observed_ranges': event.get('observed_ranges') or [],
'before': before,
'after': after,
}
def result(self, include_images=False):
files = {}
for key, entry in self.files.items():
files[_key_str(key)] = {
'name': entry.name,
'df': entry.df,
'fid': entry.fid,
'sfi': entry.sfi,
'structure': entry.structure,
'size': entry.size,
'record_len': entry.record_len,
'n_records': entry.n_records,
'counters': dict(entry.counters),
'coverage': entry.coverage(),
'image_truncated': entry.image_truncated,
'changes_total': entry.changes_total,
'changes': entry.changes,
}
timeline = [{k: v for k, v in item.items() if k != 'entry'}
for item in self.timeline]
return {
'timeline': timeline,
'timeline_total': len(timeline),
'files': files,
'sfi_relations': {df: {str(k): v for k, v in m.items()}
for df, m in self.sfi_relations.items()},
'aid_labels': dict(self.aid_labels),
}
def _merge_image(target, source):
"""Merge *source*'s observed image into *target* (used when a provisional
SFI entry joins its resolved counterpart)."""
if len(target.buf) < len(source.buf):
target.buf.extend(b'\x00' * (len(source.buf) - len(target.buf)))
target.mask.extend(b'\x00' * (len(source.buf) - len(target.mask)))
for i, value in enumerate(source.buf):
if source.mask[i] and not target.mask[i]:
target.buf[i] = value
target.mask[i] = 1
for record, buf in source.records.items():
mask = source.rec_mask[record]
dst = target.records.setdefault(record, bytearray())
dst_mask = target.rec_mask.setdefault(record, bytearray())
if len(dst) < len(buf):
dst.extend(b'\x00' * (len(buf) - len(dst)))
dst_mask.extend(b'\x00' * (len(buf) - len(dst_mask)))
for i, value in enumerate(buf):
if mask[i] and not dst_mask[i]:
dst[i] = value
dst_mask[i] = 1