The unlocker performs the DVD bus-auth that clears the drive's
scrambled-read barrier, letting a protected DVD be read at all. That is
a property of the DVD medium, not of the CSS scheme — the descramble key
is recovered keylessly downstream — so naming it "CSS" conflated the
read-enable with the encryption. Rename the struct to DvdUnlocker, its
registry name to "DVD", and the tests to match. Bump 1.5.2.
Replace the single matches()+unlock() contract with two capability methods — unlock_features (drive riplock/speed/OEM VID at drive-prep) and unlock_bus (AACS/CSS bus-encryption removal for the mounted disc) — each defaulting to NotApplicable so an unlocker implements only what it does.
Add the renesis module: the Renesas-platform unlocker (Pioneer + HL-DT-ST Renesas), detected via the READ_BUFFER 0x02/0xF1 identity probe (ASCII "SAT" marker). Features only; the cert handles the bus.
Add product_id to DriveId. Bump to 1.2.3.
Each unlocker now carries its own stable name() (the single source; apps
never hardcode it) and a report-only applies_to() — phase-independent
'would this apply to this drive+disc', distinct from the dispatch-gated
matches(). LibreDrive overrides applies_to to report on drive identity
regardless of disc kind (its matches() is gated to the Unknown-kind init
phase). Enables a registry-driven unlocker matrix.
Stage 3: the CSS bus-authentication (the challenge-response that sets the
drive's ASF=1 to unlock scrambled-sector reads, plus crypt_key + the CSS
tables) moves out of libfreemkv into the self-contained src/css module, with
its own error type. CssUnlocker impls crate::Unlocker — matches DiscKind::Css,
self-guards against a non-DVD profile, runs the bus-auth, and returns an empty
Unlocked (CSS yields no VID/bus key; the keyless Stevenson descramble stays in
libfreemkv). The keyless descramble (lfsr/stevenson) is NOT moved — that's
content decryption, the consumer's job.
all_unlockers() now returns [LibreDrive, AacsCert, CssUnlocker] — the entire
unlock layer is built. libfreemkv rewires onto it in stage 4. 89 tests pass.