Three things learned from probing a live card, plus the capability they enabled:
1. Counter tracking follows SPI1.b5b4 (TS 102 225 5.1.1): with 00 the counter
is "present, ignored, never updated", so a packet without a counter check
must leave every counter untouched. _counter_tracked() now guards
/api/send-ota (no final_cntr, no persistence, a log line), the RAM step
sender and the test runner; _preset_counter_persist() requires a non-zero
key version (the "single keyset" fallback could advance a keyset spuriously
for a keyless send). The PWA advances the form counter only when the server
reports final_cntr and says "counter not tracked" otherwise.
2. The spec's no-security form builds again: _ota_keyset() refused the valid
KIc/KID '00' (TS 102 225 A.2: '00' is legal with SPI1.b3=0 for KIc and
SPI1.b2b1=00 for KID) because pySim wants an algorithm. An unknown nibble
is now refused only when the algorithm is actually used (ciphering / a
ciphered PoR for KIc, RC/CC/DS / a MAC'd PoR for KID) and 'implicit' codes
the nibble as 0 otherwise - POST /api/send-ota {apdu, spi1:"00", kic:"00",
kid:"00"} now builds 0D00010000B0000000000000010000A40000, the exact packet
the card accepted (a fake 15/15 was refused with 6200). A no-security PoR
is decodable again too, and a requested-but-missing PoR sets por_missing
on the plain path as well.
3. TAR probe (POST /api/tar-probe, RAM op "Probe TARs"): one secured packet per
TAR - the standard allocations of TS 101 220 V18.3.0 Annex D, Table D.1
(TAR_PROBE_TARS), or a custom list - carrying a harmless C-APDU (SELECT MF)
with the preset's keyset and SPI 16/01. Each TAR is classified
(registered / no_answer / no_por / refused) from the ENVELOPE verdict and
the application's PoR, counters advance and persist normally, and the run is
refused when SPI1 has no counter check. Live on a card: 000000, B00000 and
B00001 registered (compact-format applications, answering 6D00 / 6B00),
the expanded-format TARs, USAT, multiplexing and CASD refused with 6200 -
with the keyless form the same card accepted every TAR and answered no PoR.
Docs (api.md, help EN/RU, AGENTS), sw cache simple-v337. Tests: 618 Python
(no-security build, the algorithm-only-when-used rule, the tracking rule, the
persist guard, the probe classification) and 736 Node (the probe renderer and
wiring, spCounterTracked).
A card usually holds several OTA key sets, and the SCP80 counter is tracked
per key version on the card, so a preset now carries one keyset per
GlobalPlatform key version - the b8..b5 nibble of KIc/KID (TS 102 225
5.1.2/A.2), the version is implicit in the bytes. The spec is explicit:
"a dedicated counter shall be associated to each key version" (Annex A.1) and
"the key version number indicated in the KIc and KID (bits b8..b5) fields
shall be identical when different from 0" - a mismatch is rejected by the card
with "Unidentified security error" (A.2).
Server (presets.py, schema 2):
- a preset carries `keysets: [{kic, kid, kicKey, kidKey, cntr}]`; validation
refuses a KIc/KID version mismatch (A.2), a version outside 01-0F ('00'
means "no security" and is a packet-level choice, not a keyset), duplicate
versions and missing keys/counters; a v3.8.0 flat preset converts into one
keyset on load and on import;
- `set_counter(..., kvn)` writes the counter of that keyset (monotonic per
keyset), the audit line carries the kvn, and `find_keyset()` serves the
lookups;
- the operations derive the key version from the request's KIc byte and
persist into that keyset: /api/send-ota, the RAM install/install-app/compat
steps (_ram_send_gp_apdu) and the test runner's SCP80 steps (which may name
a `kvn` per step and keep one working counter per keyset);
- a non-zero key version the named preset does not define, or a KIc/KID
mismatch, is refused before anything is built (_preset_keyset_check /
_keyset_guard: 400, or a step error in the test runner). Without a
preset_id only the mismatch rule applies.
PWA:
- the Cards form's KIc/KID/counter/keys inputs become a keyset editor (one row
per version: KIc, KID, both keys, that version's counter, Add/Remove; the
version is shown derived from the bytes and a mismatch is flagged);
- the SCP80 and RAM views get a Key-version selector beside the preset
selector, driving the KIc/KID bytes and loading that keyset's keys and
counter; the packet builder refuses a version the preset does not define
(spKeysetCheck/spKeysetGuard, pure and unit-tested);
- the counter syncs are per keyset (spCntrLocalSync/ramSaveCntr), the SCP80
form's counter edit posts the keysets, and the test-run write-back syncs
every counter the server reports (scp80_counters).
Docs/help/AGENTS updated; sw cache simple-v335. Tests: 610 Python (store
keysets, endpoint refusals, the counter landing in the right keyset) and 726
Node (keysets.test.js plus the updated harnesses).
catarrh