A block read repeats one 32 bit word, so every offset yields a rotation and more
than one can pass the structural checks. A T5577 in direct/nrz carried both
00080040, the word on the tag, and 00080001, its ror19 - both master key 0,
reserved 0, RF/32, direct. test() answers with the first hit from a fixed floor,
so which one detect reported was scan order rather than evidence.
No structural check separates them: every bit of block 0 is a real field, and
the three the scan skips are otp, fast write and inverse data, all settable. The
tag can, though - maxblock has to account for what regular read mode cycles
through. So measure the broadcast period and keep the rotation that agrees,
reusing the constraint printConfiguration already applies to the psk2/psk3
pre-images. Costs one acquisition, and only when the reading is ambiguous.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
GetT55xxBlockData extracted every block at config.offset, a bit index into a
demod buffer cached by the last detect - a different capture. Demodulators do
not all start on the same bit, so a later read could return a rotation of the
block with nothing marking it as wrong: psk1 by four or five bits, fsk2a and
nrz by one, manchester and biphase never.
Record the boundary where it is stable instead. Every demodulator reports the
graph sample its first bit sits on, and turn_read_lf_on(137 * 8) makes the
firmware open each read acquisition at the same point, so the word boundary
lands on the same sample every time. Convert back per demodulation.
Block 0 re-anchors from its known value, and a write is now verified by the
value being anywhere in the repeating stream rather than at one cached offset -
which also fixes correct writes reporting as validation failures. A block 0
verify re-detects on a mismatch, not only on a decode failure: the pre-write
config can decode the post-write signal into garbage rather than failing.
Also fixes a -1 password sentinel truncated to 32 bits by a ternary, which made
that detect report a password that was never supplied.
Measured on a T5577 across psk1, fsk2a and direct/nrz: three consecutive dumps
agree field for field, against a baseline where psk1 corrupted 22 of 24.
Co-Authored-By: Claude Opus 5 (1M context)
# Updates
1. Updated `MEGACASH` vendor name from `Bank Mega` to `PT Bank Mega Tbk` *which is the vendor's full name*.
-r&y.
Signed-off-by: ry4000 <154689120+ry4000@users.noreply.github.com>
# Updates
1. Updated `Fermax` AID to reflect the parent company's name/country and DESFire PACS product.
Signed-off-by: ry4000 <154689120+ry4000@users.noreply.github.com>
# Updates
1. Changed `type` from `e-amusement` to `arcade` for:
- Bandai Namco Passport
- Konami e-amusement pass
- Sega Aime
- Taito NESiCA
2. Updated `description` to include the full name and `(AIC)` annotation to note that this information only applies to the Amusement IC Card variants as opposed to MFC/ICODE SLI/MFC/MFU, respectively.
-r&y.
Signed-off-by: ry4000 <154689120+ry4000@users.noreply.github.com>
Simulation now completes the full exchange with a genuine Paxton reader in
password mode, and crypto mode read/write passes Proxmark-to-Proxmark.
Firmware:
- SOF was one bit period short. The lead-in that compensated for the lost
head half bit was removed and nothing replaced it, so readers rejected
every answer with a second START_AUTH. Default is now 6.
- The edge-detect threshold was latched before being measured, so the value
chosen depended on whether the Proxmark was in a field when sim started.
It is now measured on field entry and re-armed when the reader leaves.
- The percentile walk latched on run-scoped variables, so one attempt made
outside a field poisoned every later one.
- Field loss was detected from TIMESTAMP, which is free-running MCU time and
never stalls. Detect it from receive silence instead.
- Frames of a length the protocol does not have no longer reach the state
machine; our own modulation tail was resetting the session and breaking
every write.
- A dropped edge merges two or three reader bit periods into one gap. Those
bits were discarded; they are now recovered by decomposition, which is what
made crypto mode work (AUTH decode 15% -> 100%).
- Threshold selection is limited to 20 and 32 and settles in under 25 ms.
Client:
- lf hitag info printed a hardcoded 0x06 and reported 'Password mode' for
every tag. It now reads page 3, takes -k (4 bytes password, 6 bytes
crypto), and says so when the config cannot be read.
- lf hitag restore: writes a dump back in dependency order - user pages,
then key material, then config last - validates the config byte, and
prints the credential the tag will require afterwards.
- lf hitag crack2 now reports why it failed instead of a bare 'fail'.
- trace list: bit count moved to its own column, relative mode shows a
Frame Delay Time row rather than renaming Start/End, --frame and -r
rejected together.
