v1.2.2: bump version (unified release)

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.

Cargo.toml

@@ -1,13 +1,28 @@
-# freemkv-unlock — unlocker plugins for libfreemkv.
-#
-# libfreemkv ships only the `Unlocker` trait + registry and stays firmware-clean.
-# Each member here is one concrete unlocker, registered into libfreemkv by a
-# single `register_unlocker(...)` line in the consuming binary — so dropping an
-# unlocker is deleting that one line plus the dependency (delete-to-comply).
-#
-# Members:
-#   ld — LibreDrive (MediaTek MT1959 firmware unlock)
-#   (future unlockers go here as additional members)
-[workspace]
-resolver = "2"
-members = ["ld"]
+[package]
+name = "freemkv-unlock"
+version = "1.2.2"
+edition = "2024"
+rust-version = "1.86"
+license = "AGPL-3.0-only"
+description = "Unlock layer for the freemkv toolchain: the Unlocker contract + self-contained firmware/AACS/CSS unlocker modules. libfreemkv depends on this and dispatches via all_unlockers()."
+repository = "https://github.com/freemkv/freemkv-unlock"
+# NEVER crates.io: this crate carries drive firmware. Consumed only by git tag.
+publish = false
+
+[features]
+# Off by default. Exposes ld's unlock-handshake wire format (`UNLOCK_MARKER`,
+# `is_unlock_read_buffer`) for the bdemu test-emulator, which impersonates an
+# ld-unlockable drive. Real clients never enable it and keep the generic API.
+emulation = []
+
+[dependencies]
+serde = { version = "1", features = ["derive"] }
+serde_json = "1"
+base64 = "0.22.1"
+tracing = "0.1"
+num-bigint = "0.4"
+num-traits = "0.2"
+sha1 = "0.10"
+sha2 = "0.10"
+aes = "0.8"
+rand = "0.8"

README.md

@@ -1,21 +1,27 @@
 # freemkv-unlock
 
-Unlocker plugins for [libfreemkv](https://github.com/freemkv/libfreemkv).
+The unlock layer for the freemkv toolchain.
 
-libfreemkv ships only the pluggable `Unlocker` trait + registry and stays
-firmware-clean — it contains no concrete unlock code. Each crate in this
-workspace implements one unlocker and is registered into libfreemkv by a single
-line in the consuming binary:
+An **unlocker removes a drive-level bus-encryption barrier** so the drive serves
+readable (de-bus'd / de-scrambled) sectors. Content-key decryption is a separate
+concern — the consumer's job.
+
+This crate defines the `Unlocker` contract and a generic SCSI transport
+contract, and holds the self-contained unlocker modules. The consumer
+([libfreemkv](https://github.com/freemkv/libfreemkv)) depends on this crate and
+dispatches through `all_unlockers()`; it never names an individual unlocker, and
+clients of libfreemkv are oblivious to unlockers entirely (as they are to the
+SCSI layer).
 
 ```rust
-libfreemkv::register_unlocker(Box::new(my_unlocker::MyUnlocker::new()));
+for u in freemkv_unlock::all_unlockers() {
+    if u.matches(&ctx) {
+        return u.unlock(&mut scsi, &ctx);
+    }
+}
 ```
 
-Removing an unlocker is deleting that one line and the dependency
-(delete-to-comply).
-
-## Members
-
-Each member is a self-contained unlocker plugin — see its own README for details.
+To remove an unlocker, delete its module directory and its one line in
+`all_unlockers()` — nothing else changes.
 
 License: AGPL-3.0-only.

ld/Cargo.toml

@@ -1,15 +0,0 @@
-[package]
-name = "freemkv-unlock-ld"
-version = "1.0.0-rc.5.1"
-edition = "2024"
-rust-version = "1.86"
-license = "AGPL-3.0-only"
-description = "LibreDrive unlocker plugin for libfreemkv (firmware unlock for MediaTek MT1959 drives)"
-repository = "https://github.com/freemkv/freemkv-unlock"
-
-[dependencies]
-libfreemkv = "1.0.0-rc.5.1"
-serde = { version = "1", features = ["derive"] }
-serde_json = "1"
-base64 = "0.22.1"
-tracing = "0.1"

ld/README.md

@@ -1,54 +0,0 @@
-# freemkv-unlock-ld
-
-The **LibreDrive** unlocker plugin for [libfreemkv](https://github.com/freemkv/libfreemkv).
-
-libfreemkv ships only the `Unlocker` trait + registry and stays firmware-clean.
-This crate owns *how* MediaTek MT1959 drives are firmware-unlocked: the bundled
-drive-profile database (`profiles.json`), the firmware blobs, the
-WRITE_BUFFER / MODE SELECT upload, the unlock CDBs, and the variant-A / variant-B
-handshake logic.
-
-## Usage
-
-Register the unlocker once at process start, before any rip:
-
-```rust
-libfreemkv::register_unlocker(Box::new(freemkv_unlock_ld::LibreDrive::new()));
-```
-
-That single line is the whole plug. Any drive whose identity matches a bundled
-profile is firmware-unlocked at drive-prep; everything else falls through to
-libfreemkv's host-certificate AACS handshake.
-
-## The `Unlocker` contract
-
-This crate is the LibreDrive unlocker — an implementation of libfreemkv's
-`Unlocker` trait. The trait is a 3-method capability contract:
-
-- `unlock_drive` — put the drive into extended-access mode. The one required
-  capability.
-- `read_volume_id` — read the disc Volume ID directly, bypassing the AACS cert
-  handshake. `None` → libfreemkv falls back to the cert-based read. No-op
-  default.
-- `set_max_read_speed` — raise the drive to its maximum read speed. No-op
-  default.
-
-libfreemkv's AACS layer is the always-present baseline; it uses an unlocker's
-capabilities when one matches, and does the full cert handshake when none do.
-Remove this crate and libfreemkv still compiles and rips — every capability
-falls back to the OEM/baseline path.
-
-## Scope: RAM microcode only (`#2`), never the bootloader flash (`#1`)
-
-freemkv uploads the RAM microcode to an **already-bootloader-flashed** drive.
-The permanent bootloader flash (`#1`) is the drive owner's one-time manual
-step; it is **never** automated by freemkv. This crate only performs the
-non-persistent `#2` step — the microcode lives in RAM and is gone on power
-cycle.
-
-## Credits
-
-LibreDrive was created by **Mike Chen** and the **MakeMKV team**. This crate
-builds on their work — our thanks and full credit to them for the LibreDrive
-capabilities.
-

ld/src/lib.rs

@@ -1,354 +0,0 @@
-//! freemkv-unlock-ld — the LibreDrive unlocker plugin for libfreemkv.
-//!
-//! This crate owns *how* MediaTek MT1959 drives are firmware-unlocked:
-//! the bundled drive profiles, the firmware blobs, the WRITE_BUFFER /
-//! MODE SELECT upload, the unlock CDBs, and the variant-A / variant-B
-//! handshake logic. libfreemkv knows none of it — it only exposes the
-//! [`libfreemkv::Unlocker`] trait and a registry.
-//!
-//! Plug it in once at process start:
-//!
-//! ```no_run
-//! libfreemkv::register_unlocker(Box::new(freemkv_unlock_ld::LibreDrive::new()));
-//! ```
-//!
-//! With that one line, any drive whose identity matches a bundled profile
-//! is firmware-unlocked at drive-prep; everything else falls through to
-//! libfreemkv's host-certificate AACS handshake.
-
-// libfreemkv module aliases so the moved firmware code keeps its original
-// `crate::error::*` / `crate::scsi::*` paths.
-pub(crate) use libfreemkv::{error, scsi};
-
-pub mod cdb;
-pub mod profile;
-
-mod platform;
-
-use error::{Error, Result};
-use libfreemkv::{DriveId, ScsiTransport, Unlocker};
-use scsi::DataDirection;
-
-/// The LibreDrive unlocker.
-///
-/// Matches a drive against the bundled profile database and, on a hit,
-/// runs the MediaTek MT1959 firmware-unlock (and disc-speed calibration)
-/// handshake over the raw SCSI transport.
-pub struct LibreDrive;
-
-impl LibreDrive {
-    pub fn new() -> Self {
-        LibreDrive
-    }
-}
-
-impl Default for LibreDrive {
-    fn default() -> Self {
-        Self::new()
-    }
-}
-
-impl Unlocker for LibreDrive {
-    fn name(&self) -> &str {
-        "LibreDrive"
-    }
-
-    fn matches(&self, id: &DriveId) -> bool {
-        profile::find_bundled(id).is_some()
-    }
-
-    fn unlock_drive(&self, scsi: &mut dyn ScsiTransport, id: &DriveId) -> Result<()> {
-        let Some(m) = profile::find_bundled(id) else {
-            // matches() returned true but the profile vanished — treat as
-            // "nothing to do"; the caller falls back to the cert handshake.
-            return Ok(());
-        };
-        let is_variant_b = matches!(m.platform, profile::Platform::Mt1959B);
-        if matches!(m.platform, profile::Platform::Renesas) {
-            // Renesas firmware unlock is not implemented; leave the drive
-            // untouched so the host-cert handshake carries the disc.
-            return Ok(());
-        }
-        use platform::PlatformDriver;
-        let mut mt = platform::mt1959::Mt1959::new(m.profile, is_variant_b);
-        // Firmware unlock. On success, prime the per-region speed table so
-        // the drive manages zone speeds internally (best-effort — probe
-        // calibration failure must not fail an otherwise-good unlock).
-        mt.init(scsi)?;
-        let _ = mt.probe_disc(scsi);
-        Ok(())
-    }
-
-    /// OEM Volume ID retrieval.
-    ///
-    /// An unlocker unlocks drive *functionality*, not just the disc: VID
-    /// retrieval via the drive's OEM CDB is a capability separate from
-    /// `unlock`. This recovers the per-drive READ_BUFFER VID path that lived
-    /// in libfreemkv before the unlocker refactor (it was `read_vid_oem` in
-    /// `libfreemkv/src/disc/encrypt.rs`), now living inside the unlocker
-    /// where the per-drive `read_vid_cdb` template belongs.
-    ///
-    /// Returns:
-    ///   * `Ok(Some(vid))` — the drive's profile carries an OEM VID CDB and
-    ///     the drive served a well-formed VID. No host certificate or HRL is
-    ///     involved — VID is decoupled from the cert chain.
-    ///   * `Ok(None)` — no profile matched, or the profile carries no OEM VID
-    ///     CDB; libfreemkv falls back to the cert-based VID read.
-    ///   * `Err(_)` — the OEM CDB ran but returned a short or malformed
-    ///     response.
-    ///
-    /// Response layout (36 bytes):
-    ///   * `[0..3]`   3-byte response signature; expected `00 22 00`
-    ///   * `[3]`      reserved
-    ///   * `[4..20]`  16-byte Volume ID
-    ///   * `[20..36]` reserved / per-drive padding
-    fn read_volume_id(
-        &self,
-        scsi: &mut dyn ScsiTransport,
-        id: &DriveId,
-    ) -> Result<Option<[u8; 16]>> {
-        const RESPONSE_LEN: usize = 36;
-        const EXPECTED_HEADER: [u8; 3] = [0x00, 0x22, 0x00];
-
-        // No matching profile, or a profile without an OEM VID CDB → no OEM
-        // path; the caller falls back to the cert handshake.
-        let Some(m) = profile::find_bundled(id) else {
-            return Ok(None);
-        };
-        let Some(cdb) = m.profile.read_vid_cdb else {
-            return Ok(None);
-        };
-
-        let mut buf = vec![0u8; RESPONSE_LEN];
-        let result = scsi.execute(&cdb, DataDirection::FromDevice, &mut buf, 5_000)?;
-        if result.bytes_transferred < RESPONSE_LEN {
-            tracing::warn!(
-                target: "freemkv::disc",
-                phase = "oem_vid_short_response",
-                bytes_transferred = result.bytes_transferred,
-                "OEM VID CDB returned short response"
-            );
-            return Err(Error::AacsVidRead);
-        }
-        if buf[0..3] != EXPECTED_HEADER {
-            tracing::warn!(
-                target: "freemkv::disc",
-                phase = "oem_vid_bad_header",
-                header_0 = buf[0],
-                header_1 = buf[1],
-                header_2 = buf[2],
-                "OEM VID response header mismatch"
-            );
-            return Err(Error::AacsVidRead);
-        }
-        let mut vid = [0u8; 16];
-        vid.copy_from_slice(&buf[4..20]);
-        tracing::debug!(
-            target: "freemkv::disc",
-            phase = "oem_vid_ok",
-            "OEM VID retrieved via unlocker"
-        );
-        Ok(Some(vid))
-    }
-
-    /// Raise the drive to its maximum read speed.
-    ///
-    /// Issues the matched profile's `set_speed_max_cdb` (the
-    /// `0xBB SET CD SPEED`-to-max command) over the raw transport. A profile
-    /// without a `set_speed_max_cdb` (or no matching profile at all) is a
-    /// no-op — the drive stays at its current speed.
-    fn set_max_read_speed(&self, scsi: &mut dyn ScsiTransport, id: &DriveId) -> Result<()> {
-        let Some(m) = profile::find_bundled(id) else {
-            return Ok(());
-        };
-        let Some(cdb) = m.profile.set_speed_max_cdb else {
-            return Ok(());
-        };
-        let mut buf = [0u8; 0];
-        scsi.execute(&cdb, DataDirection::None, &mut buf, 5_000)?;
-        tracing::debug!(
-            target: "freemkv::drive",
-            phase = "set_max_read_speed",
-            "issued SET CD SPEED (max) via unlocker"
-        );
-        Ok(())
-    }
-}
-
-#[cfg(test)]
-mod tests {
-    use super::*;
-    use scsi::{DataDirection, ScsiResult, ScsiTransport};
-
-    /// A fake transport that fills the response buffer from a fixed payload
-    /// and reports a configurable transferred-byte count. Exercises the OEM
-    /// VID response-parse branches without a live drive.
-    struct FakeTransport {
-        payload: Vec<u8>,
-        bytes_transferred: usize,
-    }
-    impl ScsiTransport for FakeTransport {
-        fn execute(
-            &mut self,
-            _cdb: &[u8],
-            _dir: DataDirection,
-            data: &mut [u8],
-            _timeout_ms: u32,
-        ) -> Result<ScsiResult> {
-            let n = self.payload.len().min(data.len());
-            data[..n].copy_from_slice(&self.payload[..n]);
-            Ok(ScsiResult {
-                status: 0,
-                bytes_transferred: self.bytes_transferred,
-                sense: [0u8; 32],
-            })
-        }
-    }
-
-    /// A DriveId for the bundled HL-DT-ST profile that carries a real
-    /// `read_vid_cdb`, so `read_vid` finds a profile and issues the CDB.
-    fn known_vid_drive_id() -> DriveId {
-        make_drive_id("HL-DT-ST", "1.01", "NM00100", "211711202000")
-    }
-
-    fn make_drive_id(vendor: &str, rev: &str, vs: &str, date: &str) -> DriveId {
-        let mut inquiry = vec![0u8; 96];
-        inquiry[8..8 + vendor.len().min(8)]
-            .copy_from_slice(&vendor.as_bytes()[..vendor.len().min(8)]);
-        inquiry[32..32 + rev.len().min(4)].copy_from_slice(&rev.as_bytes()[..rev.len().min(4)]);
-        inquiry[36..36 + vs.len().min(7)].copy_from_slice(&vs.as_bytes()[..vs.len().min(7)]);
-        DriveId::from_inquiry(&inquiry, date)
-    }
-
-    /// A well-formed 36-byte response (signature 00 22 00, VID at [4..20])
-    /// parses to that VID.
-    #[test]
-    fn read_vid_parses_well_formed_response() {
-        // Confirm the bundled profile actually carries a read_vid_cdb;
-        // otherwise read_vid would short-circuit to Ok(None) and this test
-        // wouldn't exercise the parse path.
-        let m = profile::find_bundled(&known_vid_drive_id()).expect("profile match");
-        assert!(
-            m.profile.read_vid_cdb.is_some(),
-            "test fixture drive must carry an OEM VID CDB"
-        );
-
-        let mut payload = vec![0u8; 36];
-        payload[0..3].copy_from_slice(&[0x00, 0x22, 0x00]);
-        let vid = [0x3Cu8; 16];
-        payload[4..20].copy_from_slice(&vid);
-        let mut t = FakeTransport {
-            payload,
-            bytes_transferred: 36,
-        };
-        let got = LibreDrive::new()
-            .read_volume_id(&mut t, &known_vid_drive_id())
-            .expect("parse ok");
-        assert_eq!(got, Some(vid), "VID parsed from [4..20]");
-    }
-
-    /// A short response (fewer than 36 transferred bytes) → AacsVidRead.
-    #[test]
-    fn read_vid_short_response_errors() {
-        let mut t = FakeTransport {
-            payload: vec![0u8; 36],
-            bytes_transferred: 20,
-        };
-        let err = LibreDrive::new()
-            .read_volume_id(&mut t, &known_vid_drive_id())
-            .expect_err("short response must error");
-        assert!(matches!(err, Error::AacsVidRead));
-    }
-
-    /// A response whose 3-byte signature isn't `00 22 00` → AacsVidRead.
-    #[test]
-    fn read_vid_bad_header_errors() {
-        let mut payload = vec![0u8; 36];
-        payload[0..3].copy_from_slice(&[0xDE, 0xAD, 0xBE]); // wrong signature
-        let mut t = FakeTransport {
-            payload,
-            bytes_transferred: 36,
-        };
-        let err = LibreDrive::new()
-            .read_volume_id(&mut t, &known_vid_drive_id())
-            .expect_err("bad header must error");
-        assert!(matches!(err, Error::AacsVidRead));
-    }
-
-    /// A drive with no matching profile → Ok(None) (cert fallback), and the
-    /// transport is never issued a CDB.
-    #[test]
-    fn read_vid_no_profile_is_none() {
-        let mut t = FakeTransport {
-            payload: vec![0u8; 36],
-            bytes_transferred: 36,
-        };
-        let got = LibreDrive::new()
-            .read_volume_id(&mut t, &make_drive_id("FAKE-VND", "9.99", "XX12345", ""))
-            .expect("no-profile is Ok(None)");
-        assert!(got.is_none(), "no profile → cert fallback");
-    }
-
-    /// A transport that records the CDB issued (and how many CDBs it saw),
-    /// so the speed test can assert the profile's `set_speed_max_cdb` is the
-    /// one sent — or that nothing was sent at all (no-op).
-    struct RecordingTransport {
-        last_cdb: Vec<u8>,
-        calls: usize,
-    }
-    impl ScsiTransport for RecordingTransport {
-        fn execute(
-            &mut self,
-            cdb: &[u8],
-            _dir: DataDirection,
-            _data: &mut [u8],
-            _timeout_ms: u32,
-        ) -> Result<ScsiResult> {
-            self.last_cdb = cdb.to_vec();
-            self.calls += 1;
-            Ok(ScsiResult {
-                status: 0,
-                bytes_transferred: 0,
-                sense: [0u8; 32],
-            })
-        }
-    }
-
-    /// A matched drive whose profile carries `set_speed_max_cdb` → that exact
-    /// CDB is issued.
-    #[test]
-    fn set_max_read_speed_issues_profile_cdb() {
-        let m = profile::find_bundled(&known_vid_drive_id()).expect("profile match");
-        let expected = m
-            .profile
-            .set_speed_max_cdb
-            .expect("test fixture drive must carry a set_speed_max_cdb");
-
-        let mut t = RecordingTransport {
-            last_cdb: Vec::new(),
-            calls: 0,
-        };
-        LibreDrive::new()
-            .set_max_read_speed(&mut t, &known_vid_drive_id())
-            .expect("set_max_read_speed ok");
-        assert_eq!(t.calls, 1, "exactly one CDB issued");
-        assert_eq!(
-            t.last_cdb,
-            expected.to_vec(),
-            "the profile's set_speed_max_cdb"
-        );
-    }
-
-    /// A drive with no matching profile → no-op: no CDB issued, Ok(()).
-    #[test]
-    fn set_max_read_speed_no_profile_is_noop() {
-        let mut t = RecordingTransport {
-            last_cdb: Vec::new(),
-            calls: 0,
-        };
-        LibreDrive::new()
-            .set_max_read_speed(&mut t, &make_drive_id("FAKE-VND", "9.99", "XX12345", ""))
-            .expect("no-profile is a no-op Ok(())");
-        assert_eq!(t.calls, 0, "no profile → no CDB issued");
-    }
-}

src/aacs/error.rs

@@ -0,0 +1,88 @@
+//! aacs's internal error for the cert-handshake SCSI/crypto code. Mirrors the
+//! handshake's original libfreemkv error surface (the specific Aacs* failure
+//! points + a structured SCSI error), so the moved handshake body is unchanged.
+
+use crate::scsi::{SCSI_STATUS_TRANSPORT_FAILURE, ScsiSense};
+
+pub type Result<T> = std::result::Result<T, Error>;
+
+// A few variants are matched (defensive arms in the handshake) but never
+// constructed in the wired path — kept for completeness.
+#[allow(dead_code)]
+#[derive(Debug, Clone)]
+pub enum Error {
+    AacsAgidAlloc,
+    AacsCertRead,
+    AacsCertRejected,
+    AacsCertShort,
+    AacsCertVerify,
+    AacsDataKey,
+    AacsKeyRead,
+    AacsKeyRejected,
+    AacsKeyVerify,
+    AacsNoKeys,
+    AacsVidMac,
+    AacsVidRead,
+    HandshakeRejected,
+    VidUnavailable,
+    /// A SCSI command failed. `status == SCSI_STATUS_TRANSPORT_FAILURE` with
+    /// `sense: None` is a transport-layer fault; a CHECK CONDITION carries the
+    /// parsed [`ScsiSense`].
+    Scsi {
+        /// CDB opcode that failed — diagnostic, carried for future logging.
+        opcode: u8,
+        status: u8,
+        sense: Option<ScsiSense>,
+    },
+}
+
+impl Error {
+    /// Stable numeric code (logged). Values are local to this crate.
+    pub fn code(&self) -> u16 {
+        match self {
+            Error::AacsAgidAlloc => 7001,
+            Error::AacsCertRead => 7002,
+            Error::AacsCertRejected => 7003,
+            Error::AacsCertShort => 7004,
+            Error::AacsCertVerify => 7005,
+            Error::AacsDataKey => 7006,
+            Error::AacsKeyRead => 7007,
+            Error::AacsKeyRejected => 7008,
+            Error::AacsKeyVerify => 7009,
+            Error::AacsNoKeys => 7010,
+            Error::AacsVidMac => 7011,
+            Error::AacsVidRead => 7012,
+            Error::HandshakeRejected => 7013,
+            Error::VidUnavailable => 7014,
+            Error::Scsi { .. } => 7099,
+        }
+    }
+
+    /// The parsed sense for a CHECK CONDITION SCSI error, else `None`.
+    pub fn scsi_sense(&self) -> Option<ScsiSense> {
+        match self {
+            Error::Scsi { sense, .. } => *sense,
+            _ => None,
+        }
+    }
+
+    /// True if this is a transport-layer SCSI failure (bus dead).
+    pub fn is_scsi_transport_failure(&self) -> bool {
+        matches!(
+            self,
+            Error::Scsi { status, sense: None, .. } if *status == SCSI_STATUS_TRANSPORT_FAILURE
+        )
+    }
+}
+
+/// A generic transport fault from the SCSI contract converts in (opcode unknown
+/// at the transport level; sense parsed from the raw buffer when present).
+impl From<crate::scsi::ScsiError> for Error {
+    fn from(e: crate::scsi::ScsiError) -> Self {
+        Error::Scsi {
+            opcode: 0,
+            status: e.status,
+            sense: e.sense.map(|s| ScsiSense::from_buf(&s)),
+        }
+    }
+}

src/aacs/mod.rs

@@ -0,0 +1,119 @@
+//! aacs — the AACS host-certificate unlocker (Blu-ray / UHD).
+//!
+//! Self-contained module: it owns the cert-handshake EC crypto (the AKE, bus-key
+//! derivation, P-160 / P-256 curve math) that REMOVES AACS bus encryption. It
+//! implements [`crate::Unlocker`], learning the Volume ID + AACS 2.x bus key.
+//! Content-key decryption (unit keys, MKB, VUK) is the consumer's job, not here.
+
+mod error;
+mod handshake;
+
+use aes::Aes128;
+use aes::cipher::{BlockDecrypt, KeyInit, generic_array::GenericArray};
+
+use crate::scsi::ScsiTransport;
+use crate::{DiscKind, UnlockCtx, UnlockError, Unlocked, Unlocker};
+
+/// AES-128-ECB decrypt a single 16-byte block — used to decrypt the bus key /
+/// read_data_key the drive returns after the handshake.
+pub(crate) fn aes_ecb_decrypt(key: &[u8; 16], data: &[u8; 16]) -> [u8; 16] {
+    let cipher = Aes128::new(GenericArray::from_slice(key));
+    let mut block = GenericArray::clone_from_slice(data);
+    cipher.decrypt_block(&mut block);
+    let mut out = [0u8; 16];
+    out.copy_from_slice(&block);
+    out
+}
+
+/// The AACS host-certificate unlocker. Matches a Blu-ray/UHD disc
+/// (`DiscKind::Aacs`) and runs the cert handshake against the host certs the
+/// consumer collected (via [`UnlockCtx::host_certs`]), learning the Volume ID
+/// and — on AACS 2.0 — the bus key.
+pub struct AacsCert;
+
+impl AacsCert {
+    pub fn new() -> Self {
+        AacsCert
+    }
+}
+
+impl Default for AacsCert {
+    fn default() -> Self {
+        Self::new()
+    }
+}
+
+impl Unlocker for AacsCert {
+    fn name(&self) -> &'static str {
+        "AACS"
+    }
+
+    fn matches(&self, ctx: &UnlockCtx) -> bool {
+        ctx.kind == DiscKind::Aacs
+    }
+
+    fn unlock(
+        &self,
+        scsi: &mut dyn ScsiTransport,
+        ctx: &UnlockCtx,
+    ) -> std::result::Result<Unlocked, UnlockError> {
+        if ctx.host_certs.is_empty() {
+            // No host cert to authenticate with — the consumer falls back to a
+            // VID-less / keysource path.
+            return Err(UnlockError::NoUsableHostCert);
+        }
+        let h = handshake::run_cert_handshake(scsi, ctx.host_certs)?;
+        Ok(Unlocked {
+            vid: Some(h.volume_id),
+            // Host-cert AKE path: bus removal depends on the bus key, not a
+            // firmware unlock.
+            bus_key: h.read_data_key,
+            drive_unlocked: false,
+        })
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    fn id() -> crate::DriveId {
+        crate::DriveId::default()
+    }
+
+    /// AacsCert matches only `DiscKind::Aacs`.
+    #[test]
+    fn matches_only_aacs_kind() {
+        let id = id();
+        let u = AacsCert::new();
+        for k in [DiscKind::Unknown, DiscKind::Unencrypted, DiscKind::Css] {
+            assert!(
+                !u.matches(&UnlockCtx::new(&id, k, &[])),
+                "must not match {k:?}"
+            );
+        }
+        assert!(u.matches(&UnlockCtx::new(&id, DiscKind::Aacs, &[])));
+    }
+
+    /// With no host certs there is nothing to authenticate with → NoUsableHostCert,
+    /// and the transport is never touched.
+    #[test]
+    fn no_host_certs_is_no_usable_host_cert() {
+        struct DeadTransport;
+        impl ScsiTransport for DeadTransport {
+            fn execute(
+                &mut self,
+                _cdb: &[u8],
+                _dir: crate::scsi::DataDirection,
+                _data: &mut [u8],
+                _timeout_ms: u32,
+            ) -> crate::scsi::Result<crate::scsi::ScsiResult> {
+                panic!("transport must not be touched with no host certs");
+            }
+        }
+        let id = id();
+        let mut t = DeadTransport;
+        let r = AacsCert::new().unlock(&mut t, &UnlockCtx::new(&id, DiscKind::Aacs, &[]));
+        assert_eq!(r.unwrap_err(), UnlockError::NoUsableHostCert);
+    }
+}

src/css/error.rs

@@ -0,0 +1,41 @@
+//! css's internal error for the CSS bus-auth code. Distinct from
+//! [`crate::UnlockError`] (the outcome the consumer sees).
+
+pub type Result<T> = std::result::Result<T, Error>;
+
+#[derive(Debug, Clone)]
+pub enum Error {
+    /// The CSS bus-authentication challenge-response failed.
+    CssAuthFailed,
+    /// A SCSI transport-layer fault.
+    Scsi(crate::scsi::ScsiError),
+}
+
+impl Error {
+    /// Stable numeric code (logged). Values are local to this crate.
+    pub fn code(&self) -> u16 {
+        match self {
+            Error::CssAuthFailed => 7201,
+            Error::Scsi(_) => 7299,
+        }
+    }
+}
+
+impl From<crate::scsi::ScsiError> for Error {
+    fn from(e: crate::scsi::ScsiError) -> Self {
+        Error::Scsi(e)
+    }
+}
+
+/// CSS bus-auth either enables scrambled reads or it doesn't — any failure means
+/// "this unlocker didn't apply" (a transport fault still surfaces as Transport).
+impl From<Error> for crate::UnlockError {
+    fn from(e: Error) -> Self {
+        match e {
+            Error::Scsi(s) if s.status == crate::scsi::SCSI_STATUS_TRANSPORT_FAILURE => {
+                crate::UnlockError::Transport
+            }
+            _ => crate::UnlockError::NotApplicable,
+        }
+    }
+}

src/ld/error.rs

@@ -0,0 +1,76 @@
+//! ld's internal error type for the firmware-unlock SCSI/handshake code.
+//! Distinct from [`crate::UnlockError`] (the unlock OUTCOME the consumer sees);
+//! this is the low-level error ld's code uses. Maps both ways: a generic
+//! [`crate::scsi::ScsiError`] transport fault converts IN, and an `Error`
+//! converts OUT to the contract's `UnlockError`.
+
+pub type Result<T> = std::result::Result<T, Error>;
+
+#[derive(Debug, Clone, PartialEq, Eq)]
+pub enum Error {
+    /// A bundled drive profile could not be parsed (malformed hex / length).
+    ProfileParse,
+    /// A handshake completed but the device did not reach the expected state.
+    UnlockFailed,
+    /// A verify/handshake response did not match the expected signature.
+    SignatureMismatch { expected: [u8; 4], got: [u8; 4] },
+    /// A SCSI command failed. `status == SCSI_STATUS_TRANSPORT_FAILURE` with
+    /// `sense: None` is a transport-layer fault (bridge crash / disconnect).
+    Scsi {
+        opcode: u8,
+        status: u8,
+        sense: Option<[u8; 32]>,
+    },
+}
+
+impl std::fmt::Display for Error {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        match self {
+            Error::ProfileParse => write!(f, "drive profile parse error"),
+            Error::UnlockFailed => write!(f, "firmware unlock failed"),
+            Error::SignatureMismatch { .. } => write!(f, "signature mismatch"),
+            Error::Scsi { opcode, status, .. } => {
+                write!(f, "SCSI error (opcode {opcode:#04x}, status {status:#04x})")
+            }
+        }
+    }
+}
+
+impl std::error::Error for Error {}
+
+impl Error {
+    /// True if this is a transport-layer SCSI failure (bus dead), as opposed to a
+    /// drive sense or a logical failure.
+    pub(crate) fn is_transport_failure(&self) -> bool {
+        matches!(
+            self,
+            Error::Scsi { status, sense: None, .. }
+                if *status == crate::scsi::SCSI_STATUS_TRANSPORT_FAILURE
+        )
+    }
+}
+
+/// A generic transport fault from the SCSI contract converts into ld's error
+/// (the opcode is unknown at the transport level).
+impl From<crate::scsi::ScsiError> for Error {
+    fn from(e: crate::scsi::ScsiError) -> Self {
+        Error::Scsi {
+            opcode: 0,
+            status: e.status,
+            sense: e.sense,
+        }
+    }
+}
+
+/// ld's internal error converts OUT to the contract outcome: a dead bus is a
+/// hard `Transport` abort; any other firmware failure means "this unlocker
+/// didn't apply" → the consumer falls through to the next unlocker.
+impl From<Error> for crate::UnlockError {
+    fn from(e: Error) -> Self {
+        if e.is_transport_failure() {
+            crate::UnlockError::Transport
+        } else {
+            crate::UnlockError::NotApplicable
+        }
+    }
+}

src/ld/mod.rs

@@ -0,0 +1,302 @@
+//! ld — the LibreDrive firmware unlocker (MediaTek MT1959).
+//!
+//! Self-contained module: it owns the bundled drive profiles, firmware blobs,
+//! the WRITE_BUFFER / MODE SELECT upload, the unlock CDBs, and the variant-A /
+//! variant-B handshake. It implements [`crate::Unlocker`] — removing AACS bus
+//! encryption AT THE DRIVE (the unlocked drive serves clear content) and
+//! reporting the OEM Volume ID.
+
+// `cdb` carries ONLY the unlock-handshake wire format that the bdemu emulator
+// needs (the real unlocker drives its CDBs from per-drive profile templates, not
+// these constants). Compile it only when the `emulation` feature exposes it, so
+// it never dead-codes in a normal build.
+#[cfg(feature = "emulation")]
+mod cdb;
+mod error;
+mod platform;
+mod profile;
+
+use crate::ld::error::Result;
+use crate::scsi::{DataDirection, ScsiTransport};
+use crate::{DriveId, UnlockCtx, UnlockError, Unlocked, Unlocker};
+
+// ── Public profile catalog ──────────────────────────────────────────────────
+//
+// The catalog of drives the LibreDrive unlocker recognizes is the one piece of
+// ld worth exposing publicly: it answers "is this drive supported?" without
+// unlocking, and the bdemu test-emulator reads it to impersonate a supported
+// drive. The unlock *mechanism* (firmware blobs, upload sequence, CDB wire
+// format) stays private — only the catalog and its match result are public.
+
+pub use profile::{DriveProfile as Profile, Identity, Platform, ProfileMatch, Profiles};
+
+/// The bundled LibreDrive profile catalog (parsed once, process-cached), or
+/// `None` if the embedded JSON fails to parse (a build-time bug). Pair with
+/// [`Profiles::get`] to look up a specific drive:
+/// `freemkv_unlock::ld::profiles().and_then(|p| p.get(&drive_id))`.
+pub fn profiles() -> Option<&'static Profiles> {
+    profile::bundled()
+}
+
+/// The bundled profile matching a drive identity, if the drive is supported.
+/// Convenience over [`profiles`] + [`Profiles::get`].
+pub fn profile(drive_id: &DriveId) -> Option<ProfileMatch> {
+    profile::find_bundled(drive_id)
+}
+
+/// The unlock-handshake wire format the bdemu test-emulator needs to impersonate
+/// an ld-unlockable drive: the marker an unlocked drive returns and the
+/// READ BUFFER mode/buf-id that constitutes an unlock request. Behind the
+/// non-default `emulation` feature so real clients never see ld's wire format.
+#[cfg(feature = "emulation")]
+pub use cdb::{UNLOCK_MARKER, is_unlock_read_buffer};
+
+/// The LibreDrive unlocker. `pub(crate)` — clients reach it only through
+/// [`crate::all_unlockers`], never by name (the locked-design contract).
+///
+/// Matches a drive against the bundled profile database and, on a hit,
+/// runs the MediaTek MT1959 firmware-unlock (and disc-speed calibration)
+/// handshake over the raw SCSI transport.
+pub(crate) struct LibreDrive;
+
+impl LibreDrive {
+    pub(crate) fn new() -> Self {
+        LibreDrive
+    }
+}
+
+/// The firmware-unlocker name for a drive that has a bundled profile (for
+/// drive-info "is this drive supported?" display), or `None`. A pure profile
+/// lookup — does NOT touch the drive or unlock anything.
+pub(crate) fn firmware_name(id: &DriveId) -> Option<&'static str> {
+    profile::find_bundled(id).map(|_| "LibreDrive")
+}
+
+impl LibreDrive {
+    /// Read the OEM Volume ID via the matched profile's vendor CDB.
+    ///
+    /// `Ok(Some(vid))` on a well-formed 36-byte response (signature `00 22 00`,
+    /// VID at `[4..20]`); `Ok(None)` when there is no OEM-VID CDB or the response
+    /// is short / bad-signature (the drive is still unlocked, just no VID); `Err`
+    /// only on a transport fault.
+    fn read_oem_vid(&self, scsi: &mut dyn ScsiTransport, id: &DriveId) -> Result<Option<[u8; 16]>> {
+        const RESPONSE_LEN: usize = 36;
+        const EXPECTED_HEADER: [u8; 3] = [0x00, 0x22, 0x00];
+
+        let Some(m) = profile::find_bundled(id) else {
+            return Ok(None);
+        };
+        let Some(cdb) = m.profile.read_vid_cdb else {
+            return Ok(None);
+        };
+
+        let mut buf = vec![0u8; RESPONSE_LEN];
+        let result = scsi.execute(&cdb, DataDirection::FromDevice, &mut buf, 5_000)?;
+        if result.bytes_transferred < RESPONSE_LEN {
+            tracing::warn!(
+                target: "freemkv::disc",
+                phase = "oem_vid_short_response",
+                bytes_transferred = result.bytes_transferred,
+                "OEM VID CDB returned short response"
+            );
+            return Ok(None);
+        }
+        if buf[0..3] != EXPECTED_HEADER {
+            tracing::warn!(
+                target: "freemkv::disc",
+                phase = "oem_vid_bad_header",
+                "OEM VID response header mismatch"
+            );
+            return Ok(None);
+        }
+        let mut vid = [0u8; 16];
+        vid.copy_from_slice(&buf[4..20]);
+        tracing::debug!(target: "freemkv::disc", phase = "oem_vid_ok", "OEM VID retrieved via unlocker");
+        Ok(Some(vid))
+    }
+}
+
+impl Unlocker for LibreDrive {
+    /// Firmware unlock is a DRIVE-PREP concern: it runs before the disc kind is
+    /// probed (`kind == Unknown`) and keys off the drive identity. It must NOT
+    /// fire during the later content-keyed dispatch (Aacs/Css), or a DVD/Blu-ray
+    /// in a profiled drive would be re-firmware-unlocked.
+    fn name(&self) -> &'static str {
+        "LibreDrive"
+    }
+
+    fn matches(&self, ctx: &UnlockCtx) -> bool {
+        ctx.kind == crate::DiscKind::Unknown && profile::find_bundled(ctx.drive_id).is_some()
+    }
+
+    /// Firmware-unlock the drive and report its OEM Volume ID. The unlocked drive
+    /// serves CLEAR content, so `drive_unlocked: true` and there is no bus key.
+    ///
+    /// A no-firmware-route drive (Renesas) returns `NotApplicable` (fall through);
+    /// a transport fault propagates as `Transport`; a firmware failure that isn't
+    /// a dead bus also falls through (`NotApplicable`).
+    fn unlock(
+        &self,
+        scsi: &mut dyn ScsiTransport,
+        ctx: &UnlockCtx,
+    ) -> std::result::Result<Unlocked, UnlockError> {
+        let id = ctx.drive_id;
+        let Some(m) = profile::find_bundled(id) else {
+            return Err(UnlockError::NotApplicable);
+        };
+        if matches!(m.platform, profile::Platform::Renesas) {
+            // Renesas firmware unlock is not implemented — fall through to cert.
+            return Err(UnlockError::NotApplicable);
+        }
+        let is_variant_b = matches!(m.platform, profile::Platform::Mt1959B);
+        use platform::PlatformDriver;
+        let mut mt = platform::mt1959::Mt1959::new(m.profile, is_variant_b);
+        // Firmware unlock. A transport fault → UnlockError::Transport; any other
+        // firmware failure → NotApplicable (via From<error::Error>).
+        mt.init(scsi)?;
+        // Prime the per-region speed table (best-effort — must not fail the unlock).
+        let _ = mt.probe_disc(scsi);
+        // The unlocked drive hands back its Volume ID; firmware serves clear
+        // content, so no bus key and drive_unlocked = true.
+        let vid = self.read_oem_vid(scsi, id)?;
+        Ok(Unlocked {
+            vid,
+            bus_key: None,
+            drive_unlocked: true,
+        })
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use crate::DiscKind;
+    use crate::scsi::{DataDirection, ScsiResult, ScsiTransport};
+
+    /// Unlock context for a fake drive id (kind/host-certs irrelevant to the
+    /// firmware unlocker — it keys off the drive identity).
+    fn ctx(id: &DriveId) -> UnlockCtx<'_> {
+        UnlockCtx::new(id, DiscKind::Unknown, &[])
+    }
+
+    /// A fake transport that fills the response buffer from a fixed payload and
+    /// reports a configurable transferred-byte count.
+    struct FakeTransport {
+        payload: Vec<u8>,
+        bytes_transferred: usize,
+    }
+    impl ScsiTransport for FakeTransport {
+        fn execute(
+            &mut self,
+            _cdb: &[u8],
+            _dir: DataDirection,
+            data: &mut [u8],
+            _timeout_ms: u32,
+        ) -> crate::scsi::Result<ScsiResult> {
+            let n = self.payload.len().min(data.len());
+            data[..n].copy_from_slice(&self.payload[..n]);
+            Ok(ScsiResult {
+                status: 0,
+                bytes_transferred: self.bytes_transferred,
+                sense: [0u8; 32],
+            })
+        }
+    }
+
+    /// A DriveId for the bundled HL-DT-ST profile that carries a real
+    /// `read_vid_cdb`, so `read_oem_vid` finds a profile and issues the CDB.
+    fn known_vid_drive_id() -> DriveId {
+        make_drive_id("HL-DT-ST", "1.01", "NM00100", "211711202000")
+    }
+
+    fn make_drive_id(vendor: &str, rev: &str, vs: &str, date: &str) -> DriveId {
+        DriveId {
+            vendor_id: vendor.to_string(),
+            product_revision: rev.to_string(),
+            vendor_specific: vs.to_string(),
+            firmware_date: date.to_string(),
+        }
+    }
+
+    /// A well-formed 36-byte response (signature 00 22 00, VID at [4..20]) parses
+    /// to `Some(vid)`.
+    #[test]
+    fn read_oem_vid_parses_well_formed_response() {
+        let m = profile::find_bundled(&known_vid_drive_id()).expect("profile match");
+        assert!(
+            m.profile.read_vid_cdb.is_some(),
+            "test fixture drive must carry an OEM VID CDB"
+        );
+
+        let mut payload = vec![0u8; 36];
+        payload[0..3].copy_from_slice(&[0x00, 0x22, 0x00]);
+        let vid = [0x3Cu8; 16];
+        payload[4..20].copy_from_slice(&vid);
+        let mut t = FakeTransport {
+            payload,
+            bytes_transferred: 36,
+        };
+        let got = LibreDrive::new()
+            .read_oem_vid(&mut t, &known_vid_drive_id())
+            .expect("parse ok");
+        assert_eq!(got, Some(vid), "VID parsed from [4..20]");
+    }
+
+    /// A short response → `Ok(None)` (drive unlocked, just no readable VID).
+    #[test]
+    fn read_oem_vid_short_response_is_none() {
+        let mut t = FakeTransport {
+            payload: vec![0u8; 36],
+            bytes_transferred: 20,
+        };
+        let got = LibreDrive::new()
+            .read_oem_vid(&mut t, &known_vid_drive_id())
+            .expect("short response is Ok(None)");
+        assert_eq!(got, None);
+    }
+
+    /// A response whose 3-byte signature isn't `00 22 00` → `Ok(None)`.
+    #[test]
+    fn read_oem_vid_bad_header_is_none() {
+        let mut payload = vec![0u8; 36];
+        payload[0..3].copy_from_slice(&[0xDE, 0xAD, 0xBE]);
+        let mut t = FakeTransport {
+            payload,
+            bytes_transferred: 36,
+        };
+        let got = LibreDrive::new()
+            .read_oem_vid(&mut t, &known_vid_drive_id())
+            .expect("bad header is Ok(None)");
+        assert_eq!(got, None);
+    }
+
+    /// A drive with no matching profile → `read_oem_vid` is `Ok(None)`.
+    #[test]
+    fn read_oem_vid_no_profile_is_none() {
+        let mut t = FakeTransport {
+            payload: vec![0u8; 36],
+            bytes_transferred: 36,
+        };
+        let got = LibreDrive::new()
+            .read_oem_vid(&mut t, &make_drive_id("FAKE-VND", "9.99", "XX12345", ""))
+            .expect("no profile is Ok(None)");
+        assert_eq!(got, None);
+    }
+
+    /// `unlock` on a drive with no matching profile → `NotApplicable` (fall
+    /// through), short-circuiting before any firmware handshake.
+    #[test]
+    fn unlock_no_profile_is_not_applicable() {
+        let mut t = FakeTransport {
+            payload: vec![0u8; 36],
+            bytes_transferred: 36,
+        };
+        let err = LibreDrive::new()
+            .unlock(
+                &mut t,
+                &ctx(&make_drive_id("FAKE-VND", "9.99", "XX12345", "")),
+            )
+            .expect_err("no profile → NotApplicable");
+        assert_eq!(err, UnlockError::NotApplicable);
+    }
+}

src/ld/platform/mod.rs

@@ -2,7 +2,7 @@
 
 pub mod mt1959;
 
-use crate::error::Result;
+use crate::ld::error::Result;
 use crate::scsi::ScsiTransport;
 
 pub(crate) trait PlatformDriver: Send {

src/ld/platform/mt1959/mod.rs

@@ -4,8 +4,8 @@ mod variant_a;
 mod variant_b;
 
 use super::PlatformDriver;
-use crate::error::{Error, Result};
-use crate::profile::DriveProfile;
+use crate::ld::error::{Error, Result};
+use crate::ld::profile::DriveProfile;
 use crate::scsi::{self, DataDirection, ScsiTransport};
 
 // ── Variant constants ──────────────────────────────────────────────────
@@ -124,7 +124,7 @@ impl Mt1959 {
         let cdb = self.read_buffer_sub(sub_cmd, address, expected as u8);
         let result = scsi.execute(&cdb, DataDirection::FromDevice, buf, 5_000)?;
         if result.bytes_transferred != expected {
-            return Err(Error::ScsiError {
+            return Err(Error::Scsi {
                 opcode: SCSI_READ_BUFFER,
                 status: crate::scsi::SCSI_STATUS_TRANSPORT_FAILURE,
                 sense: None,
@@ -217,7 +217,7 @@ impl Mt1959 {
                 return Ok(());
             }
         }
-        Err(Error::ScsiError {
+        Err(Error::Scsi {
             opcode: SCSI_READ_BUFFER,
             status: crate::scsi::SCSI_STATUS_TRANSPORT_FAILURE,
             sense: None,
@@ -327,7 +327,7 @@ impl Mt1959 {
                 )
                 .is_err()
             {
-                return Err(Error::ScsiError {
+                return Err(Error::Scsi {
                     opcode: SCSI_READ_BUFFER,
                     status: crate::scsi::SCSI_STATUS_TRANSPORT_FAILURE,
                     sense: None,
@@ -397,7 +397,7 @@ impl PlatformDriver for Mt1959 {
 #[cfg(test)]
 mod tests {
     use super::*;
-    use crate::profile::{DriveProfile, Identity};
+    use crate::ld::profile::{DriveProfile, Identity};
     use crate::scsi::{DataDirection, ScsiResult, ScsiTransport};
 
     /// Minimal mock transport that returns a scripted response to the
@@ -414,7 +414,7 @@ mod tests {
             _dir: DataDirection,
             data: &mut [u8],
             _timeout_ms: u32,
-        ) -> Result<ScsiResult> {
+        ) -> crate::scsi::Result<ScsiResult> {
             let n = self.response.len().min(data.len());
             data[..n].copy_from_slice(&self.response[..n]);
             Ok(ScsiResult {
@@ -437,7 +437,7 @@ mod tests {
             _dir: DataDirection,
             _data: &mut [u8],
             _timeout_ms: u32,
-        ) -> Result<ScsiResult> {
+        ) -> crate::scsi::Result<ScsiResult> {
             self.cdbs.push(cdb.to_vec());
             // Empty response → do_unlock's signature check fails, so the unlock
             // loop exhausts — but the firmware-load CDBs (incl. the F1 verify)

src/ld/platform/mt1959/variant_a.rs

@@ -3,7 +3,7 @@
 //! WRITE_BUFFER (0x3B) → verify READ_BUFFER (0x45) → unlock × 2
 
 use super::Mt1959;
-use crate::error::Result;
+use crate::ld::error::Result;
 use crate::scsi::{DataDirection, ScsiTransport};
 
 use super::SCSI_WRITE_BUFFER;
@@ -17,7 +17,7 @@ const WRITE_BUFFER_MAX_LEN: usize = 0x00FF_FFFF;
 pub(super) fn load_firmware(mt: &mut Mt1959, scsi: &mut dyn ScsiTransport) -> Result<()> {
     let firmware = &mt.profile.firmware;
     if firmware.is_empty() {
-        return Err(crate::error::Error::UnlockFailed);
+        return Err(crate::ld::error::Error::UnlockFailed);
     }
 
     // Upload firmware via WRITE_BUFFER. The CDB's length is a 24-bit field;
@@ -26,7 +26,7 @@ pub(super) fn load_firmware(mt: &mut Mt1959, scsi: &mut dyn ScsiTransport) -> Re
     // length-mismatched command.
     let len = firmware.len();
     if len > WRITE_BUFFER_MAX_LEN {
-        return Err(crate::error::Error::UnlockFailed);
+        return Err(crate::ld::error::Error::UnlockFailed);
     }
     let cdb = [
         SCSI_WRITE_BUFFER,

src/ld/platform/mt1959/variant_b.rs

@@ -3,7 +3,7 @@
 //! MODE SELECT (0x55) → read metadata → WRITE_BUFFER → vendor verify (0xF1) → unlock × 5+1
 
 use super::{Mt1959, SCSI_READ_BUFFER, SCSI_WRITE_BUFFER};
-use crate::error::Result;
+use crate::ld::error::Result;
 use crate::scsi::{DataDirection, ScsiTransport};
 
 const SCSI_MODE_SELECT: u8 = 0x55;
@@ -16,7 +16,7 @@ const VENDOR_VERIFY: [u8; 10] = [0xF1, 0x01, 0x02, 0x00, 0x0D, 0x30, 0x01, 0xF3,
 pub(super) fn load_firmware(mt: &mut Mt1959, scsi: &mut dyn ScsiTransport) -> Result<()> {
     let firmware = &mt.profile.firmware;
     if firmware.is_empty() {
-        return Err(crate::error::Error::UnlockFailed);
+        return Err(crate::ld::error::Error::UnlockFailed);
     }
 
     // Step 1: Upload the firmware via MODE SELECT. The profile's `firmware` is
@@ -27,7 +27,7 @@ pub(super) fn load_firmware(mt: &mut Mt1959, scsi: &mut dyn ScsiTransport) -> Re
     // expressed in the CDB.
     let write_len = firmware.len();
     if write_len > u16::MAX as usize {
-        return Err(crate::error::Error::UnlockFailed);
+        return Err(crate::ld::error::Error::UnlockFailed);
     }
     let mode_select_cdb = [
         SCSI_MODE_SELECT,

src/ld/profile.rs

@@ -1,11 +1,13 @@
 //! Drive profile loading and matching.
 
-use crate::error::{Error, Result};
+use crate::ld::error::{Error, Result};
 use serde::Deserialize;
 
-/// Top-level profiles file — keyed by chipset + variant.
+/// The LibreDrive profile catalog — the set of optical drives the firmware
+/// unlocker recognizes, keyed by chipset + variant. Loaded from the bundled
+/// JSON; the public entry point is [`crate::ld::profiles`].
 #[derive(Debug, Deserialize)]
-pub struct ProfilesFile {
+pub struct Profiles {
     #[serde(default)]
     pub mt1959_a: Vec<DriveProfile>,
     #[serde(default)]
@@ -14,6 +16,15 @@ pub struct ProfilesFile {
     pub renesas: Vec<DriveProfile>,
 }
 
+impl Profiles {
+    /// The profile matching a drive identity, if this catalog supports that
+    /// drive. Two-pass per platform section: exact (incl. firmware date) then a
+    /// looser vendor/revision/vendor-specific match. See [`find_by_drive_id`].
+    pub fn get(&self, drive_id: &crate::DriveId) -> Option<ProfileMatch> {
+        find_by_drive_id(self, drive_id)
+    }
+}
+
 /// Drive identity — matched against INQUIRY data.
 #[derive(Debug, Clone, Deserialize)]
 pub struct Identity {
@@ -233,14 +244,13 @@ where
 
 // ── Loading ────────────────────────────────────────────────────────────
 
-const BUNDLED_PROFILES: &str = include_str!("../profiles.json");
+const BUNDLED_PROFILES: &str = include_str!("profiles.json");
 
-/// Parse the bundled profiles fresh into an owned [`ProfilesFile`].
-///
-/// Re-parses the embedded JSON (~800 KB) on every call; prefer
-/// [`bundled`] for the hot path, which parses once and caches. This
-/// owned form is kept for callers that need a mutable / independent copy.
-pub fn load_bundled() -> Result<ProfilesFile> {
+/// Parse the bundled profiles fresh into an owned [`Profiles`]. Test-only — the
+/// library hot path uses the cached [`bundled`]; tests use this owned form for
+/// independent copies.
+#[cfg(test)]
+pub fn load_bundled() -> Result<Profiles> {
     load_from_str(BUNDLED_PROFILES)
 }
 
@@ -250,9 +260,9 @@ pub fn load_bundled() -> Result<ProfilesFile> {
 /// Returns `None` if the embedded JSON fails to parse (a build-time bug —
 /// the bundled blob is fixed at compile time, so the first successful call
 /// guarantees all later calls succeed too).
-pub fn bundled() -> Option<&'static ProfilesFile> {
+pub fn bundled() -> Option<&'static Profiles> {
     use std::sync::OnceLock;
-    static CACHE: OnceLock<Option<ProfilesFile>> = OnceLock::new();
+    static CACHE: OnceLock<Option<Profiles>> = OnceLock::new();
     CACHE
         .get_or_init(|| load_from_str(BUNDLED_PROFILES).ok())
         .as_ref()
@@ -263,11 +273,11 @@ pub fn bundled() -> Option<&'static ProfilesFile> {
 /// Convenience wrapper over [`bundled`] + [`find_by_drive_id`] that skips
 /// the per-call re-parse. Returns `None` if no profile matches (or, in the
 /// build-bug case, if the bundled JSON failed to parse).
-pub fn find_bundled(drive_id: &libfreemkv::DriveId) -> Option<ProfileMatch> {
+pub fn find_bundled(drive_id: &crate::DriveId) -> Option<ProfileMatch> {
     find_by_drive_id(bundled()?, drive_id)
 }
 
-fn load_from_str(data: &str) -> Result<ProfilesFile> {
+fn load_from_str(data: &str) -> Result<Profiles> {
     serde_json::from_str(data).map_err(|_| Error::ProfileParse)
 }
 
@@ -280,10 +290,7 @@ fn load_from_str(data: &str) -> Result<ProfilesFile> {
 /// profile; the looser pass lets a drive whose firmware date we don't have
 /// on file still match a same-model profile. All comparisons are
 /// whitespace-trimmed. Returns the first section that yields a match.
-pub fn find_by_drive_id(
-    profiles: &ProfilesFile,
-    drive_id: &libfreemkv::DriveId,
-) -> Option<ProfileMatch> {
+pub fn find_by_drive_id(profiles: &Profiles, drive_id: &crate::DriveId) -> Option<ProfileMatch> {
     let v = drive_id.vendor_id.trim();
     let r = drive_id.product_revision.trim();
     let vs = drive_id.vendor_specific.trim();
@@ -324,15 +331,15 @@ pub fn find_by_drive_id(
 #[cfg(test)]
 mod tests {
     use super::*;
-    use libfreemkv::DriveId;
+    use crate::DriveId;
 
     fn make_drive_id(vendor: &str, rev: &str, vs: &str, date: &str) -> DriveId {
-        let mut inquiry = vec![0u8; 96];
-        inquiry[8..8 + vendor.len().min(8)]
-            .copy_from_slice(&vendor.as_bytes()[..vendor.len().min(8)]);
-        inquiry[32..32 + rev.len().min(4)].copy_from_slice(&rev.as_bytes()[..rev.len().min(4)]);
-        inquiry[36..36 + vs.len().min(7)].copy_from_slice(&vs.as_bytes()[..vs.len().min(7)]);
-        DriveId::from_inquiry(&inquiry, date)
+        DriveId {
+            vendor_id: vendor.to_string(),
+            product_revision: rev.to_string(),
+            vendor_specific: vs.to_string(),
+            firmware_date: date.to_string(),
+        }
     }
 
     #[test]
@@ -374,11 +381,11 @@ mod tests {
     fn bundled_is_cached_and_matches_fresh_parse() {
         let cached = bundled().expect("bundled profiles parse");
         let fresh = load_bundled().unwrap();
-        // Same data either way (compare section sizes — ProfilesFile isn't Eq).
+        // Same data either way (compare section sizes — Profiles isn't Eq).
         assert_eq!(cached.mt1959_a.len(), fresh.mt1959_a.len());
         // Cached accessor returns a stable address across calls.
-        let a = bundled().unwrap() as *const ProfilesFile;
-        let b = bundled().unwrap() as *const ProfilesFile;
+        let a = bundled().unwrap() as *const Profiles;
+        let b = bundled().unwrap() as *const Profiles;
         assert_eq!(a, b);
     }
 
@@ -449,7 +456,7 @@ mod tests {
 
     /// find_by_drive_id: exact match (including firmware_date) wins over loose match.
     /// Spec: two-pass — first an exact match including firmware_date, then looser.
-    /// Build two synthetic ProfilesFile entries that differ only by firmware_date,
+    /// Build two synthetic Profiles entries that differ only by firmware_date,
     /// and verify the correct one is selected.
     /// Mutation: doing only the loose pass would return the first entry regardless of date.
     #[test]
@@ -483,7 +490,7 @@ mod tests {
             ]
         })
         .to_string();
-        let profiles: ProfilesFile = serde_json::from_str(&profiles_json).unwrap();
+        let profiles: Profiles = serde_json::from_str(&profiles_json).unwrap();
 
         // "TESTDRV " (with space) fills 8 bytes; trim() → "TESTDRV" on both sides.
         let id_date1 = make_drive_id("TESTDRV ", "1.00", "XX00000", "200001010000");
@@ -528,7 +535,7 @@ mod tests {
             ]
         })
         .to_string();
-        let profiles: ProfilesFile = serde_json::from_str(&profiles_json).unwrap();
+        let profiles: Profiles = serde_json::from_str(&profiles_json).unwrap();
 
         // Drive with an unknown firmware date — no exact match, loose match should work.
         // "LOOSEDR " fills 8 bytes; "000000000000" is the unknown date.
@@ -542,11 +549,11 @@ mod tests {
     }
 
     /// load_from_str (via load_bundled) returns ProfileParse on invalid JSON.
-    /// Mutation: returning an empty ProfilesFile instead of an error silently
+    /// Mutation: returning an empty Profiles instead of an error silently
     ///           leaves the drive-profile database empty.
     #[test]
     fn load_from_str_returns_profile_parse_on_bad_json() {
-        let result: Result<ProfilesFile> =
+        let result: Result<Profiles> =
             serde_json::from_str("not valid json {{{{").map_err(|_| Error::ProfileParse);
         assert!(matches!(result, Err(Error::ProfileParse)));
     }
@@ -586,7 +593,7 @@ mod tests {
             ]
         })
         .to_string();
-        let profiles: ProfilesFile = serde_json::from_str(&json_str).unwrap();
+        let profiles: Profiles = serde_json::from_str(&json_str).unwrap();
         let p = &profiles.mt1959_a[0]; // DriveProfile directly
         // All optional CDB fields must be None when absent from JSON.
         assert!(
@@ -637,7 +644,7 @@ mod tests {
             ]
         })
         .to_string();
-        let profiles: ProfilesFile = serde_json::from_str(&json_str).unwrap();
+        let profiles: Profiles = serde_json::from_str(&json_str).unwrap();
         assert_eq!(
             profiles.mt1959_a[0].signature, [0u8; 4],
             "empty signature must deserialise as [0;4]"

src/lib.rs

@@ -0,0 +1,150 @@
+//! freemkv-unlock — the unlock layer for the freemkv toolchain.
+//!
+//! An **unlocker removes a drive-level bus-encryption barrier** so the drive
+//! serves readable (de-bus'd / de-scrambled) sectors. Content-key decryption is
+//! a separate layer — the consumer's (libfreemkv's) job.
+//!
+//! This crate defines the [`Unlocker`] contract + the SCSI transport contract,
+//! and holds the self-contained unlocker modules (firmware / AACS cert / CSS).
+//! libfreemkv depends on this crate and dispatches via [`all_unlockers`]; it
+//! never names an individual unlocker. To remove an unlocker, delete its module
+//! dir and its one line in [`all_unlockers`] — nothing else changes.
+
+pub mod scsi;
+
+mod aacs;
+mod css;
+// `ld` is public ONLY for its drive-profile catalog (`ld::profiles` / the
+// `Profiles` object) and, under the `emulation` feature, the unlock-handshake
+// wire format the bdemu test-emulator needs. The unlocker impl itself
+// (`LibreDrive`) is `pub(crate)` — clients still reach unlockers only through
+// [`all_unlockers`]. `aacs` and `css` carry no such public catalog, so they
+// stay fully private.
+pub mod ld;
+
+use scsi::ScsiTransport;
+
+/// Drive identity an unlocker matches against — four raw INQUIRY-derived fields,
+/// filled by the consumer (this crate parses no INQUIRY itself).
+#[derive(Debug, Clone, Default)]
+pub struct DriveId {
+    pub vendor_id: String,
+    pub product_revision: String,
+    pub vendor_specific: String,
+    pub firmware_date: String,
+}
+
+/// Bus-encryption class of the mounted disc, probed by the consumer.
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+pub enum DiscKind {
+    Unknown,
+    Unencrypted,
+    Aacs,
+    Css,
+}
+
+/// A host certificate for the AACS cert handshake (raw; the consumer collects
+/// these from its key sources and passes them in).
+#[derive(Debug, Clone)]
+pub struct HostCert {
+    /// AACS 1.0 host private key (20 bytes).
+    pub private_key: [u8; 20],
+    /// AACS 1.0 host certificate (92 bytes).
+    pub certificate: Vec<u8>,
+    /// AACS 2.0 host private key (P-256, 32 bytes). `None` for AACS 1.0 only.
+    pub private_key_v2: Option<[u8; 32]>,
+    /// AACS 2.0 host certificate (type 0x11). `None` for AACS 1.0 only.
+    pub certificate_v2: Option<Vec<u8>>,
+}
+
+/// Context handed to an unlocker: drive identity, disc kind, and (for the cert
+/// route) the host certs the consumer collected.
+pub struct UnlockCtx<'a> {
+    pub drive_id: &'a DriveId,
+    pub kind: DiscKind,
+    pub host_certs: &'a [HostCert],
+}
+
+impl<'a> UnlockCtx<'a> {
+    pub fn new(drive_id: &'a DriveId, kind: DiscKind, host_certs: &'a [HostCert]) -> Self {
+        Self {
+            drive_id,
+            kind,
+            host_certs,
+        }
+    }
+}
+
+/// What removing bus encryption yielded. `drive_unlocked` means the drive now
+/// serves clear content (firmware route) — equivalent, for the gate, to a cert
+/// `bus_key`.
+#[derive(Debug, Clone, Default)]
+pub struct Unlocked {
+    pub vid: Option<[u8; 16]>,
+    pub bus_key: Option<[u8; 16]>,
+    pub drive_unlocked: bool,
+}
+
+/// Why an unlock produced no usable result. Only `Transport` is a hard error
+/// (bus dead → consumer aborts); the rest mean "fall through to the next
+/// unlocker".
+#[derive(Debug, Clone, PartialEq, Eq)]
+pub enum UnlockError {
+    /// This unlocker does not apply (wrong disc kind / no profile / no certs).
+    NotApplicable,
+    /// The AACS cert route had no usable host certificate.
+    NoUsableHostCert,
+    /// The drive rejected the auth handshake.
+    HandshakeRejected,
+    /// Auth succeeded but no Volume ID could be read.
+    VidUnavailable,
+    /// A genuine SCSI transport fault (bus dead). The consumer aborts.
+    Transport,
+}
+
+/// An unlocker removes a drive-level bus-encryption barrier. Implementors are
+/// the self-contained modules in this crate; the consumer only ever sees the
+/// trait, via [`all_unlockers`]. (Each module owns its own conversion from its
+/// internal error to [`UnlockError`].)
+///
+/// NOTE: drive tuning (e.g. SET CD SPEED to lift riplock) is deliberately NOT
+/// here — that is the consumer's concern, not bus removal.
+pub trait Unlocker: Send + Sync {
+    /// Short, stable identifier for this unlocker (e.g. "LibreDrive", "AACS",
+    /// "CSS"). The ONE place a name lives — apps render the unlocker report from
+    /// [`all_unlockers`], never hardcoding names, so adding/removing an unlocker
+    /// updates every report with no app change.
+    fn name(&self) -> &'static str;
+
+    /// True if this unlocker applies to the given context (drive id + disc kind)
+    /// during live dispatch — the gate [`crate::all_unlockers`] uses to decide
+    /// whether to RUN it.
+    fn matches(&self, ctx: &UnlockCtx) -> bool;
+
+    /// Remove the bus-encryption barrier, returning what was learned.
+    fn unlock(
+        &self,
+        scsi: &mut dyn ScsiTransport,
+        ctx: &UnlockCtx,
+    ) -> std::result::Result<Unlocked, UnlockError>;
+}
+
+/// Name of the unlocker that claims this drive by identity (for drive-info "is
+/// this drive supported?" display), or `None`. A pure lookup — does NOT touch
+/// the drive or unlock anything. Only the identity-keyed (drive-prep) unlocker
+/// can answer from a `DriveId` alone; the disc-kind-keyed unlockers (AACS / CSS)
+/// don't claim a drive sight-unseen, so they never match here.
+pub fn unlocker_name(drive_id: &DriveId) -> Option<&'static str> {
+    ld::firmware_name(drive_id)
+}
+
+/// Every unlocker, in dispatch order (firmware → cert → css). This is the ONLY
+/// place an unlocker is named. Remove one = delete its line here + its module
+/// dir; the consumer never changes.
+pub fn all_unlockers() -> Vec<Box<dyn Unlocker>> {
+    vec![
+        Box::new(ld::LibreDrive::new()),
+        Box::new(aacs::AacsCert::new()),
+        Box::new(css::CssUnlocker::new()),
+    ]
+}

src/scsi.rs

@@ -0,0 +1,100 @@
+//! The SCSI transport contract every unlocker issues CDBs through. The consumer
+//! (libfreemkv) implements [`ScsiTransport`] over its own SCSI; the unlockers
+//! never see a concrete transport. Common MMC/SPC opcodes live here too.
+
+/// Direction of a SCSI data transfer.
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+pub enum DataDirection {
+    None,
+    FromDevice,
+    ToDevice,
+}
+
+/// Result of a SCSI command: status byte, bytes transferred, raw sense.
+#[derive(Debug, Clone)]
+pub struct ScsiResult {
+    pub status: u8,
+    pub bytes_transferred: usize,
+    pub sense: [u8; 32],
+}
+
+/// A transport-layer SCSI failure (the command could not complete — bridge
+/// crash / disconnect), as opposed to a drive sense returned in [`ScsiResult`].
+#[derive(Debug, Clone)]
+pub struct ScsiError {
+    pub status: u8,
+    pub sense: Option<[u8; 32]>,
+}
+
+/// Transport-layer result.
+pub type Result<T> = std::result::Result<T, ScsiError>;
+
+/// The one capability an unlocker needs from the host: run a raw CDB. `Ok` even
+/// on a SCSI sense (inspect `status`); `Err` only on a transport-layer fault.
+pub trait ScsiTransport {
+    fn execute(
+        &mut self,
+        cdb: &[u8],
+        direction: DataDirection,
+        data: &mut [u8],
+        timeout_ms: u32,
+    ) -> Result<ScsiResult>;
+}
+
+/// Parsed SCSI sense (the diagnostic an unlocker reads off a failed command).
+#[derive(Debug, Clone, Copy)]
+pub struct ScsiSense {
+    pub sense_key: u8,
+    pub asc: u8,
+    pub ascq: u8,
+}
+
+impl ScsiSense {
+    /// Parse the fixed-format sense buffer (key at byte 2, ASC at 12, ASCQ at 13).
+    pub fn from_buf(sense: &[u8; 32]) -> Self {
+        ScsiSense {
+            sense_key: sense[2] & 0x0F,
+            asc: sense[12],
+            ascq: sense[13],
+        }
+    }
+    /// ILLEGAL REQUEST (sense key 0x05) — the drive won't honor the command.
+    pub fn is_illegal_request(&self) -> bool {
+        self.sense_key == 0x05
+    }
+}
+
+/// SCSI status byte for a transport-layer failure (bridge crash / disconnect).
+pub(crate) const SCSI_STATUS_TRANSPORT_FAILURE: u8 = 0xFF;
+/// SCSI status byte CHECK CONDITION (a drive sense is available). Part of the
+/// status contract; currently referenced only by tests asserting the
+/// transport-vs-check-condition distinction.
+#[allow(dead_code)]
+pub(crate) const SCSI_STATUS_CHECK_CONDITION: u8 = 0x02;
+
+// Common opcodes used by the unlocker modules.
+pub(crate) const SCSI_SET_CD_SPEED: u8 = 0xBB;
+pub(crate) const SCSI_SEND_KEY: u8 = 0xA3;
+pub(crate) const SCSI_REPORT_KEY: u8 = 0xA4;
+pub(crate) const SCSI_READ_DISC_STRUCTURE: u8 = 0xAD;
+pub(crate) const SCSI_GET_CONFIGURATION: u8 = 0x46;
+/// AACS key class selector used in REPORT/SEND KEY CDBs.
+pub(crate) const AACS_KEY_CLASS: u8 = 0x02;
+
+/// Build a SET CD SPEED (0xBB) CDB requesting `read_speed` (KB/s; 0xFFFF = max).
+pub(crate) fn build_set_cd_speed(read_speed: u16) -> [u8; 12] {
+    [
+        SCSI_SET_CD_SPEED,
+        0x00,
+        (read_speed >> 8) as u8,
+        read_speed as u8,
+        0xFF,
+        0xFF,
+        0x00,
+        0x00,
+        0x00,
+        0x00,
+        0x00,
+        0x00,
+    ]
+}