diff options
Diffstat (limited to 'tools/gen_fixture_wrap.py')
| -rw-r--r-- | tools/gen_fixture_wrap.py | 15 |
1 files changed, 11 insertions, 4 deletions
diff --git a/tools/gen_fixture_wrap.py b/tools/gen_fixture_wrap.py index 6eb207a..9daca94 100644 --- a/tools/gen_fixture_wrap.py +++ b/tools/gen_fixture_wrap.py @@ -1,6 +1,6 @@ #!/usr/bin/env python3 # Author: cirakg & claude ai -# Summary: Compute the UI-test fixture's PIN wrap (fake PIN 1234) so the watch needn't run PBKDF2 at start-up. +# Summary: Compute the UI-test fixtures' PIN wraps (fake PINs 1234 and legacy 123456): no PBKDF2 on the watch at start. """Print the fake PIN wrap that source/app/Fixtures.mc stores in the UI-test build. The wrap follows docs/SECURITY.md ("PIN wrap, version 1") with fixed, fake @@ -11,8 +11,12 @@ the fixture stores this precomputed value instead. The app's own unlock code then checks it like any other wrap, which also cross-checks the format. The fixture also stores the 4-digit PIN marker (KeyManager.PIN_LENGTH_KEY = PIN_DIGITS), so the PIN isn't treated as a legacy 4-to-10-digit one. +The extra UI-test scenario stores LEGACY_WRAP instead, the same master key +under the 6-digit PIN 123456 and without the marker: a PIN from before the +4-digit rule, which unlocks with OK and is then replaced. -Usage: gen_fixture_wrap.py (prints FIXTURE_PIN, FIXTURE_WRAP and FIXTURE_MASTER_KEY in hex, +Usage: gen_fixture_wrap.py (prints FIXTURE_PIN, FIXTURE_WRAP, FIXTURE_MASTER_KEY, + FIXTURE_LEGACY_PIN and FIXTURE_LEGACY_WRAP in hex, and the marker the fixture stores) """ @@ -24,6 +28,7 @@ import struct import subprocess PIN = b"1234" +LEGACY_PIN = b"123456" # the extra scenario's PIN from before the 4-digit rule PIN_DIGITS = 4 # source/storage/KeyManager.mc: every new PIN, and the marker value PIN_LENGTH_KEY = "wl" # source/storage/KeyManager.mc ITERATIONS = 2000 @@ -61,8 +66,8 @@ def sealed_box(enc_key: bytes, mac_key: bytes, aad: bytes, plaintext: bytes) -> return body + tag -def fixture_wrap() -> bytes: - pin_key = hashlib.pbkdf2_hmac("sha256", PIN, SALT, ITERATIONS, 32) +def fixture_wrap(pin: bytes = PIN) -> bytes: + pin_key = hashlib.pbkdf2_hmac("sha256", pin, SALT, ITERATIONS, 32) enc_key, mac_key = hkdf(pin_key, b"OTPW enc v1"), hkdf(pin_key, b"OTPW mac v1") count = struct.pack(">I", ITERATIONS) aad = b"OTPW-WRAP-1" + SALT + count @@ -74,6 +79,8 @@ def main() -> None: print("FIXTURE_PIN =", PIN.decode()) print("FIXTURE_WRAP =", fixture_wrap().hex()) print("FIXTURE_MASTER_KEY =", MASTER_KEY.hex()) + print("FIXTURE_LEGACY_PIN =", LEGACY_PIN.decode()) + print("FIXTURE_LEGACY_WRAP =", fixture_wrap(LEGACY_PIN).hex()) print(f"marker: {PIN_LENGTH_KEY} = {PIN_DIGITS}") |