equip/init: read the selected EF directly, bound the startup drain

pySim's scc.read_binary/read_record call select_path(ef) first, so the
ICCID, network-state, EF.ARR and EF.PBR readers - which had already made a
parent-scoped selection and hold its FCP - sent a second SELECT per file
and per record.  _read_selected_ef() issues READ BINARY (chunked at
max_cmd_len from the FCP file size) / READ RECORD (b2<rec>04<len> at the
FCP record length) directly; the pySim helpers stay as the fallback when
the FCP lacks the value.

The startup TERMINAL PROFILE drain now breaks on the chain's idle SW
instead of polling STATUS once more.

Measured on the last startup: ~3.4 s traced init (netstate/ARR/PBR 271
APDUs / 1.26 s incl. 169 SELECTs; the card's own TP processing 1.58 s);
the change removes ~0.7-0.8 s of the read phase without touching any data
or the TP.

v3.38.1; tests: tests/test_read_selected.py (direct reads, chunking, the
fallback and the drain source pin) and the ARR/PBR/ICCID/netstate fakes.
1067 Python + 1075 frontend.  sw cache simple-v482.

pysim_simple_server/__main__.py

@@ -293,7 +293,11 @@ def main():
                 sys.stderr.write('INIT: drain STATUS -> %s\n' % st_sw)
                 if not st_sw.startswith('91'):
                     break
-                _handle_proactive_chain(scc, st_sw)
+                chain_sw = _handle_proactive_chain(scc, st_sw)
+                # the chain's trailing STATUS already proved the card idle;
+                # polling once more only costs an APDU (v3.38.1)
+                if chain_sw and not chain_sw.startswith('91'):
+                    break
             _tlog('terminal_profile_drain: %.0fms' % ((time.time() - t_phase) * 1000))
         except Exception as e:
             if _is_pcsc_error(e):

pysim_simple_server/server.py

@@ -37,7 +37,7 @@ from osmocom.tlv import BER_TLV_IE
 from osmocom.utils import rpad
 
 
-VERSION = '3.38.0'
+VERSION = '3.38.1'
 
 MAX_ENVELOPE_SEGMENTS = 5  # max SMS segments for outgoing C-APDU in ENVELOPE
 
@@ -483,6 +483,45 @@ def _decode_iccid(data_hex):
     return digits
 
 
+def _read_selected_ef(lchan, kind, rec=None, length=None, offset=0):
+    """Read the currently selected EF **without selecting it again**.
+
+    pySim's ``scc.read_binary``/``scc.read_record`` call ``select_path(ef)``
+    first.  Our callers have already made a parent-scoped selection and hold
+    its FCP, so that second SELECT is redundant (one per file read, one per
+    record).  A transparent file is read in ``max_cmd_len`` chunks from
+    ``offset`` (the whole file when ``length`` is None, using the FCP file
+    size); a record file reads record ``rec`` (1-based) at the FCP's record
+    length.  Returns ``(data, sw)`` like the pySim helpers; falls back to them
+    when the FCP lacks the needed value.
+
+    The caller must select the file first (``_select_path``/``_select_with_parent``)
+    and must not interleave another selection before the read."""
+    scc = getattr(lchan, 'scc', None)
+    if kind == 'record':
+        rec_len = lchan.selected_file_record_len()
+        if scc is not None and rec_len:
+            pdu = scc.cla_byte + 'b2%02x04%02x' % (int(rec), rec_len)
+            return scc.send_apdu_checksw(pdu)
+        return lchan.read_record(rec)
+    size = lchan.selected_file_size()
+    if scc is None or size is None:
+        return lchan.read_binary(length, offset)
+    if length is None:
+        length = size - offset
+    if length <= 0:
+        return '', '9000'
+    total, sw = '', ''
+    chunk = 0
+    while chunk < length:
+        n = min(scc.max_cmd_len, length - chunk)
+        pdu = scc.cla_byte + 'b0%04x%02x' % (offset + chunk, n)
+        data, sw = scc.send_apdu_checksw(pdu)
+        total += data or ''
+        chunk += n
+    return total, sw
+
+
 def _read_iccid(app):
     """Best-effort EF.ICCID (MF/2FE2) read: the E.118 digit string or None.
 
@@ -495,7 +534,7 @@ def _read_iccid(app):
     cleanup = None
     try:
         _, cleanup = _select_path(lchan, 'MF/2FE2', app)
-        data, _sw = lchan.read_binary()
+        data, _sw = _read_selected_ef(lchan, 'transparent')
         return _decode_iccid(data)
     except Exception:
         return None
@@ -536,7 +575,7 @@ def _read_arr(app):
             n = min(lchan.selected_file_num_of_rec() or 1, ARR_RECORD_LIMIT)
             records = []
             for i in range(1, n + 1):
-                rv = lchan.read_record(i)
+                rv = _read_selected_ef(lchan, 'record', i)
                 data = rv[0] if isinstance(rv, tuple) else rv
                 records.append((data or '').upper())
             out.append({'fid': path.rsplit('/', 1)[-1].upper(),
@@ -602,7 +641,7 @@ def _read_pbr(app):
             n = min(lchan.selected_file_num_of_rec() or 1, PBR_RECORD_LIMIT)
             records = []
             for i in range(1, n + 1):
-                rv = lchan.read_record(i)
+                rv = _read_selected_ef(lchan, 'record', i)
                 data = rv[0] if isinstance(rv, tuple) else rv
                 records.append((data or '').upper())
             out.append({'fid': path.rsplit('/', 1)[-1].upper(),
@@ -886,14 +925,14 @@ def _netstate_read(app, keys=None):
                     records = []
                     n = lchan.selected_file_num_of_rec() or 1
                     for i in range(1, n + 1):
-                        rv = lchan.read_record(i)
+                        rv = _read_selected_ef(lchan, 'record', i)
                         data = rv[0] if isinstance(rv, tuple) else rv
                         records.append({'num': i,
                                         'data': (data or '').upper()})
                     entry.update({'present': True, 'kind': 'record',
                                   'records': records})
                 else:
-                    rv = lchan.read_binary()
+                    rv = _read_selected_ef(lchan, 'transparent')
                     data = rv[0] if isinstance(rv, tuple) else rv
                     entry.update({'present': True, 'kind': 'transparent',
                                   'data': (data or '').upper()})