aacs: extract mkb.rs (MKB record format, MkbType, finders)
Relocate the shared MKB machinery into a single mkb module: the record framing walker + MkbRecord view (from variant), the MkbType/AacsVersion classification, the MKB-file utilities, and the record-body finders (from keys). Fixes the inversion where the MKB parser lived in the 2.1-only variant module. variant.rs keeps its local MkbRecord-based mkb_find_mk_dv (name collision with the raw one; unified in the dedup follow-up). Relocation only. Proven byte-identical to the pre-refactor state via the function-body logic hash (imports normalized out); 2210 tests green.
This commit is contained in:
Matthew Jackson
+2
-1
@@ -204,7 +204,8 @@ pub fn resolve_candidate(
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unit_key_ro: &[u8],
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unit_key_ro: &[u8],
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vid: Option<Vid>,
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vid: Option<Vid>,
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) -> Option<ResolvedChain> {
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) -> Option<ResolvedChain> {
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use super::keys::{AacsVersion, derive_media_key_and_pk_from_dk, mkb_type, parse_unit_key_ro};
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use super::keys::{derive_media_key_and_pk_from_dk, parse_unit_key_ro};
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use super::mkb::{AacsVersion, mkb_type};
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// Boil a VUK → all unit keys, each paired with its declared CPS-unit number.
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// Boil a VUK → all unit keys, each paired with its declared CPS-unit number.
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// `.inf` parsing lives here: derive the stride version from the disc's own
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// `.inf` parsing lives here: derive the stride version from the disc's own
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+3
-249
@@ -1,66 +1,11 @@
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//! AACS key resolution — VUK derivation, MKB processing, disc hash, unit key parsing.
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//! AACS key resolution — VUK derivation, MKB processing, disc hash, unit key parsing.
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use super::crypto::{aes_ecb_decrypt, aesg3};
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use super::crypto::{aes_ecb_decrypt, aesg3};
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use super::mkb::*;
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use super::types::DeviceKey;
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use super::types::DeviceKey;
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// ── AACS version ────────────────────────────────────────────────────────────
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// ── AACS version ────────────────────────────────────────────────────────────
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/// AACS protection generation a disc carries.
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///
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/// The content cert byte distinguishes V10 (`0x00`) from V20 (`0x01`). V21
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/// cannot be detected from the cert alone — a V21 disc carries a V20 cert
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/// and is upgraded to `V21` only after the MKB walk turns up the real Variant
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/// records `0x2d` / `0x2f` (Encrypted Media Key Variant Data and the Variant
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/// Key Data table).
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///
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/// Key-storage stride in `Unit_Key_RO.inf` is 48 bytes for V10 and 64
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/// bytes for V20 / V21.
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#[derive(Debug, Clone, Copy, PartialEq, Eq)]
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pub enum AacsVersion {
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/// AACS 1.0 — original BD-ROM.
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V10,
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/// AACS 2.0 — UHD-BD, classical Media Key derivation.
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V20,
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/// AACS 2.1 — UHD-BD with Media Key Variant chain on top of V20.
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V21,
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}
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/// AACS major version as the small integer threaded through the scan / key
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/// paths (`AacsState.version`, `DiscInputs.version`, `DiscInputsCtx::new`):
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/// 1 = AACS 1.0 (BD), 2 = AACS 2.x (UHD). Centralised so the bare `1`/`2` — and
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/// the V10-vs-else stride choice it drives — lives in exactly one place.
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pub const AACS_MAJOR_BD: u8 = 1;
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pub const AACS_MAJOR_UHD: u8 = 2;
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impl AacsVersion {
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/// Stride (in bytes) between successive encrypted unit keys in
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/// `Unit_Key_RO.inf`.
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fn unit_key_stride(self) -> usize {
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match self {
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AacsVersion::V10 => 48,
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AacsVersion::V20 | AacsVersion::V21 => 64,
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}
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}
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/// This version as the major integer ([`AACS_MAJOR_BD`] / [`AACS_MAJOR_UHD`]).
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pub fn major(self) -> u8 {
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match self {
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AacsVersion::V10 => AACS_MAJOR_BD,
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AacsVersion::V20 | AacsVersion::V21 => AACS_MAJOR_UHD,
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}
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}
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/// The version a bare major integer selects for stride purposes: only the
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/// BD major is V10; every other value takes the V20/V21 64-byte stride.
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pub fn from_major(major: u8) -> Self {
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if major == AACS_MAJOR_BD {
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AacsVersion::V10
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} else {
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AacsVersion::V20
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}
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}
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}
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// ── VUK derivation ──────────────────────────────────────────────────────────
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// ── VUK derivation ──────────────────────────────────────────────────────────
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/// Derive VUK from Media Key and Volume ID. [PR] §3.3 / [BD] §3.3
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/// Derive VUK from Media Key and Volume ID. [PR] §3.3 / [BD] §3.3
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@@ -401,203 +346,12 @@ pub mod probe {
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}
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}
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}
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}
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/// Find Verify Media Key Record (type 0x81 for AACS 1.0, 0x86 for AACS 2.0/2.1) in MKB.
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/// 0x81: [C] §3.2.5.1.4. 0x86 (AACS 2.x): [libaacs] `mkb.c` — not in the public spec.
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fn mkb_find_mk_dv(mkb: &[u8]) -> Option<[u8; 16]> {
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// Verify-Media-Key record (0x81 for AACS 1.0, 0x86 for AACS 2.x): mk_dv is
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// the 16 bytes at record offset 4 (body offset 0). Needs rec_len >= 20.
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let found = crate::aacs::variant::mkb_records(mkb)
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.find(|&(_, rt, len)| (rt == 0x81 || rt == 0x86) && len >= 20);
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match found {
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Some((o, rec_type, rec_len)) => {
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let mut dv = [0u8; 16];
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dv.copy_from_slice(&mkb[o + 4..o + 20]);
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tracing::debug!(
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target: "freemkv::disc",
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phase = "mkb_mk_dv_found",
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rec_type,
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pos = o,
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rec_len,
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"mk_dv extracted from MKB"
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);
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Some(dv)
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}
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None => {
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tracing::warn!(
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target: "freemkv::disc",
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phase = "mkb_mk_dv_not_found",
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"no 0x81/0x86 record with rec_len>=20 found"
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);
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None
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}
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}
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}
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/// Find Subset-Difference records (type 0x04) in MKB. [C] §3.2.5.1.5.
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fn mkb_find_subdiff_records(mkb: &[u8]) -> Option<Vec<u8>> {
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find_record_body(mkb, 0x04)
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}
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/// Find the Media Key Data Record (cvalues table) in an MKB. [C] §3.2.4 / §3.2.5.1.7.
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///
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/// The cvalue table is record type `0x05` (Media Key Data) on BOTH AACS
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/// 1.0 and AACS 2.x MKBs — its 16-byte cvalue entries are 1:1 with the
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/// 5-byte Subset-Difference index entries in record `0x04`. This matches
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/// libaacs, whose `mkb_cvalues()` reads `0x05` and `mkb_subdiff_records()`
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/// reads `0x04`.
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///
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/// On AACS 2.x in-drive UHD MKBs the `0x05` table is large (the full
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/// subset-difference cvalue set: ~181k entries on a retail MKB, 1:1 with
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/// the giant `0x04` index), while record `0x07` (Explicit
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/// Subset-Difference Record) is a much smaller structure (~96 entries) and
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/// is NOT the cvalue table. An earlier version of this function preferred
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/// `0x07`, which under-tested the Subset-Difference walk on UHD discs and
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/// prevented the DK→walk path from ever finding the matching uv. The
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/// selection MUST therefore be `0x05`-first; `0x07` is only a fallback for
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/// malformed/legacy MKBs that somehow lack a `0x05` record.
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fn mkb_find_cvalues(mkb: &[u8]) -> Option<Vec<u8>> {
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if let Some(body) = find_record_body(mkb, 0x05) {
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return Some(body);
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}
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find_record_body(mkb, 0x07)
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}
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/// Walk an MKB and return the payload (header stripped) of the first
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/// record matching `rec_type`. Returns `None` if no such record exists or
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/// the record is empty.
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fn find_record_body(mkb: &[u8], rec_type_wanted: u8) -> Option<Vec<u8>> {
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crate::aacs::variant::mkb_records(mkb)
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.find(|&(_, rt, len)| rt == rec_type_wanted && len > 4)
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.map(|(o, _, len)| mkb[o + 4..o + len].to_vec())
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}
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/// Real content length of an MKB: the byte offset where the record stream
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/// ends. MKB files (especially `MKB_RW.inf`, but `MKB_RO.inf` too on some
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/// discs) are allocated to a fixed size — often ~128 MiB — with the records at
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/// the front and the rest zero padding. Walking records (type+len) and stopping
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/// at the first padding byte (`type == 0` / zero-length / overrun) gives the
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/// actual size so callers can trim off megabytes of zeros before sending or
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/// archiving. Returns `mkb.len()` only if the whole buffer parsed as records.
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pub fn mkb_content_len(mkb: &[u8]) -> usize {
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// End of the last framed record = where the fixed-region zero padding begins.
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// (The `00 000000` terminator / overrun stops the walk; real MKBs pad with
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// zeros, so this matches the prior "stop at the first padding byte".)
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crate::aacs::variant::mkb_records(mkb)
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.last()
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.map(|(o, _, len)| o + len)
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.unwrap_or(0)
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}
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/// Trim an MKB's trailing fixed-region padding to its real content length —
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/// but ONLY when [`mkb_content_len`] actually found one. It returns 0 for an
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/// MKB whose first record cannot be parsed; truncating to 0 in that case would
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/// hand downstream consumers (and the online key service) an EMPTY MKB that can
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/// never resolve. So a 0 (or a length that isn't strictly inside the buffer)
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/// leaves the MKB untouched. A 0.31.0 regression dropped this guard and
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/// `truncate`-d unconditionally, zeroing unrecognised MKBs.
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pub fn trim_mkb(mut mkb: Vec<u8>) -> Vec<u8> {
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let n = mkb_content_len(&mkb);
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if n > 0 && n < mkb.len() {
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mkb.truncate(n);
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}
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mkb
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}
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/// Get MKB version from Type and Version Record (type 0x10).
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/// Layout: 4-byte record header at `pos` (type + BE24 length), then the
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/// record body starts at `pos + 4`. The body holds the BE u32 Type field at
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/// body offset 0 (`pos + 4`), then the BE u32 version at body offset 4
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/// (`pos + 8`).
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pub fn mkb_version(mkb: &[u8]) -> Option<u32> {
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// Type-and-Version record (0x10): version is the BE u32 at body offset 4
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// (record offset 8). Needs rec_len >= 12 (4 header + 4 type + 4 version).
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crate::aacs::variant::mkb_records(mkb)
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.find(|&(_, rt, len)| rt == 0x10 && len >= 12)
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.map(|(o, _, _)| u32::from_be_bytes([mkb[o + 8], mkb[o + 9], mkb[o + 10], mkb[o + 11]]))
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}
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// ── MKB Type field (Type-and-Version record 0x10, bytes 4-7) ────────────────
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// ── MKB Type field (Type-and-Version record 0x10, bytes 4-7) ────────────────
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//
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//
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// Canonical form is `<category>1003` (low 16 bits `0x1003` is a fixed marker).
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// Canonical form is `<category>1003` (low 16 bits `0x1003` is a fixed marker).
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// Types 3/4/10 are from the AACS Common Cryptographic Elements spec (0.953,
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// Types 3/4/10 are from the AACS Common Cryptographic Elements spec (0.953,
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// §3.2.5.1.1); the Category-C 2.0/2.1 values match libaacs `mkb.h` constants.
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// §3.2.5.1.1); the Category-C 2.0/2.1 values match libaacs `mkb.h` constants.
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/// `0x00031003` — recordable media MKB (Class I & II compute Km directly).
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pub const MKB_TYPE_3_RECORDABLE: u32 = 0x0003_1003;
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/// `0x00041003` — AACS 1.0 pre-recorded content MKB (KCD-based). Standard BD.
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pub const MKB_TYPE_4_PRERECORDED: u32 = 0x0004_1003;
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/// `0x000A1003` — Class II / Unified MKB (Sequence-Key-Block functionality).
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pub const MKB_TYPE_10_CLASS_II: u32 = 0x000A_1003;
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/// `0x48141003` — AACS 2.0 Category C (UHD content). libaacs `MKB_20_CATEGORY_C`.
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pub const MKB_20_CATEGORY_C: u32 = 0x4814_1003;
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/// `0x48151003` — AACS 2.1 Category C (UHD content). libaacs `MKB_21_CATEGORY_C`.
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pub const MKB_21_CATEGORY_C: u32 = 0x4815_1003;
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/// The AACS MKB Type field, decoded.
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#[derive(Debug, Clone, Copy, PartialEq, Eq)]
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pub enum MkbType {
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/// Type 3 — recordable media.
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Recordable,
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/// Type 4 — AACS 1.0 pre-recorded content (KCD). Standard Blu-ray.
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Prerecorded,
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/// Type 10 — Class II / Unified (SKB).
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ClassII,
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/// AACS 2.0 Category C — UHD content.
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CategoryC20,
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/// AACS 2.1 Category C — UHD content.
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CategoryC21,
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/// Unrecognized MKBType value (raw field preserved).
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Other(u32),
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}
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impl MkbType {
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fn from_raw(raw: u32) -> Self {
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match raw {
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MKB_TYPE_3_RECORDABLE => MkbType::Recordable,
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MKB_TYPE_4_PRERECORDED => MkbType::Prerecorded,
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MKB_TYPE_10_CLASS_II => MkbType::ClassII,
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MKB_20_CATEGORY_C => MkbType::CategoryC20,
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MKB_21_CATEGORY_C => MkbType::CategoryC21,
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other => MkbType::Other(other),
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}
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}
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/// AACS generation this MKB belongs to (Category C → 2.0/2.1, else 1.0).
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pub fn generation(self) -> AacsVersion {
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match self {
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MkbType::CategoryC21 => AacsVersion::V21,
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MkbType::CategoryC20 => AacsVersion::V20,
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_ => AacsVersion::V10,
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}
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}
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/// `true` for UHD (AACS 2.x Category C); `false` for Blu-ray (AACS 1.x).
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pub fn is_uhd(self) -> bool {
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matches!(self, MkbType::CategoryC20 | MkbType::CategoryC21)
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}
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}
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/// The raw 32-bit MKBType field from the Type-and-Version record (0x10), bytes
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/// 4-7. `None` if no 0x10 record is present. [C] §3.2.5.1.1 Table 3-2.
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pub fn mkb_type_raw(mkb: &[u8]) -> Option<u32> {
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// Type-and-Version record (0x10): the 32-bit MKBType is bytes 4-7 (body
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// offset 0). Needs rec_len >= 8 (4 header + 4 type).
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crate::aacs::variant::mkb_records(mkb)
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.find(|&(_, rt, len)| rt == 0x10 && len >= 8)
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.map(|(o, _, _)| u32::from_be_bytes([mkb[o + 4], mkb[o + 5], mkb[o + 6], mkb[o + 7]]))
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}
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/// Decode an MKB's Type field. `None` if no Type-and-Version record is present.
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pub fn mkb_type(mkb: &[u8]) -> Option<MkbType> {
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mkb_type_raw(mkb).map(MkbType::from_raw)
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}
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/// `Some(true)` if this MKB is a UHD (AACS 2.x Category C) block, `Some(false)`
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/// for Blu-ray (AACS 1.x), `None` if the Type record is absent.
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pub fn mkb_is_uhd(mkb: &[u8]) -> Option<bool> {
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mkb_type(mkb).map(MkbType::is_uhd)
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}
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// ── AACS-G3 key derivation (subset-difference tree) ─────────────────────────
|
// ── AACS-G3 key derivation (subset-difference tree) ─────────────────────────
|
||||||
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/// Compute v_mask from a UV value. [C] §3.2.3. Shared with [`super::variants`].
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/// Compute v_mask from a UV value. [C] §3.2.3. Shared with [`super::variants`].
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@@ -1096,7 +850,7 @@ pub fn resolve_keys_v1(ctx: &ResolveContext<'_>) -> Option<ResolvedKeys> {
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pub fn resolve_keys_v2(ctx: &ResolveContext<'_>) -> Option<ResolvedKeys> {
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pub fn resolve_keys_v2(ctx: &ResolveContext<'_>) -> Option<ResolvedKeys> {
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let mut resolved = resolve_keys_classical(ctx, AacsVersion::V20)?;
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let mut resolved = resolve_keys_classical(ctx, AacsVersion::V20)?;
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if let Some(mkb) = ctx.mkb {
|
if let Some(mkb) = ctx.mkb {
|
||||||
let recs = super::variant::walk_mkb(mkb);
|
let recs = super::mkb::walk_mkb(mkb);
|
||||||
if super::variant::is_variant_mkb(&recs) {
|
if super::variant::is_variant_mkb(&recs) {
|
||||||
resolved.version = AacsVersion::V21;
|
resolved.version = AacsVersion::V21;
|
||||||
}
|
}
|
||||||
@@ -1160,7 +914,7 @@ pub fn resolve_keys_v21(ctx: &ResolveContext<'_>) -> Option<ResolvedKeys> {
|
|||||||
// Path 1: Variant chain (V21's analogue of classical Path 1's
|
// Path 1: Variant chain (V21's analogue of classical Path 1's
|
||||||
// DK derivation). Placeholder until KCD constant is supplied.
|
// DK derivation). Placeholder until KCD constant is supplied.
|
||||||
if let Some(mkb) = ctx.mkb {
|
if let Some(mkb) = ctx.mkb {
|
||||||
let recs = super::variant::walk_mkb(mkb);
|
let recs = super::mkb::walk_mkb(mkb);
|
||||||
let all_dks = providers.device_keys();
|
let all_dks = providers.device_keys();
|
||||||
match super::variant::derive_media_key_variant(
|
match super::variant::derive_media_key_variant(
|
||||||
&recs,
|
&recs,
|
||||||
|
|||||||
+325
@@ -0,0 +1,325 @@
|
|||||||
|
//! AACS Media Key Block — [C] Chapter 3.
|
||||||
|
//!
|
||||||
|
//! The MKB record format (framing walker, the `MkbRecord` view, record-body
|
||||||
|
//! finders), the MKBType / AACS-generation classification, and MKB-file
|
||||||
|
//! utilities (content length, trimming, version). Consolidated here from the
|
||||||
|
//! former `keys.rs` / `variant.rs` so the one place that understands MKB bytes
|
||||||
|
//! is `mkb`. A follow-up collapses the remaining duplicate finders (see the
|
||||||
|
//! private refactor notes) — for now both dialects live here side by side.
|
||||||
|
|
||||||
|
/// A single MKB record produced by [`walk_mkb`].
|
||||||
|
#[derive(Debug, Clone)]
|
||||||
|
pub struct MkbRecord {
|
||||||
|
/// Byte offset of the record within the MKB.
|
||||||
|
pub offset: usize,
|
||||||
|
/// Record type byte.
|
||||||
|
pub rec_type: u8,
|
||||||
|
/// Record length in bytes (includes the 4-byte header).
|
||||||
|
pub rec_len: usize,
|
||||||
|
/// Record body (the bytes after the 4-byte header).
|
||||||
|
pub body: Vec<u8>,
|
||||||
|
}
|
||||||
|
|
||||||
|
/// Walk an MKB into a flat list of records.
|
||||||
|
///
|
||||||
|
/// MKB record framing per AACS: 1 byte type, 3 bytes BE length
|
||||||
|
/// INCLUDING the 4-byte header, followed by payload. The walker stops
|
||||||
|
/// at the first `(type=0, len=0)` end marker or at end of buffer.
|
||||||
|
pub fn walk_mkb(mkb: &[u8]) -> Vec<MkbRecord> {
|
||||||
|
mkb_records(mkb)
|
||||||
|
.map(|(offset, rec_type, rec_len)| MkbRecord {
|
||||||
|
offset,
|
||||||
|
rec_type,
|
||||||
|
rec_len,
|
||||||
|
body: mkb[offset + 4..offset + rec_len].to_vec(),
|
||||||
|
})
|
||||||
|
.collect()
|
||||||
|
}
|
||||||
|
|
||||||
|
/// THE single MKB record-framing walker: yields `(offset, rec_type, rec_len)`
|
||||||
|
/// for each record — a 4-byte header (type byte + big-endian 24-bit length)
|
||||||
|
/// then the body — stopping at the `00 000000` end marker or a
|
||||||
|
/// malformed/out-of-bounds length. Lazy (no body clone), so a find-one-record
|
||||||
|
/// caller never materialises the multi-MB cvalue table. [`walk_mkb`] and every
|
||||||
|
/// MKB record walk in `aacs::keys` are built on this, so the framing rules — and
|
||||||
|
/// any future fix to them — live in exactly one place (they had drifted across
|
||||||
|
/// six hand-rolled copies).
|
||||||
|
pub(crate) fn mkb_records(mkb: &[u8]) -> impl Iterator<Item = (usize, u8, usize)> + '_ {
|
||||||
|
let mut pos = 0usize;
|
||||||
|
std::iter::from_fn(move || {
|
||||||
|
if pos + 4 > mkb.len() {
|
||||||
|
return None;
|
||||||
|
}
|
||||||
|
let rec_type = mkb[pos];
|
||||||
|
let rec_len = ((mkb[pos + 1] as usize) << 16)
|
||||||
|
| ((mkb[pos + 2] as usize) << 8)
|
||||||
|
| (mkb[pos + 3] as usize);
|
||||||
|
if rec_type == 0 && rec_len == 0 {
|
||||||
|
return None;
|
||||||
|
}
|
||||||
|
if rec_len < 4 || pos + rec_len > mkb.len() {
|
||||||
|
return None;
|
||||||
|
}
|
||||||
|
let here = pos;
|
||||||
|
pos += rec_len;
|
||||||
|
Some((here, rec_type, rec_len))
|
||||||
|
})
|
||||||
|
}
|
||||||
|
|
||||||
|
pub(crate) fn mkb_find_body(records: &[MkbRecord], rec_type: u8) -> Option<&[u8]> {
|
||||||
|
records
|
||||||
|
.iter()
|
||||||
|
.find(|r| r.rec_type == rec_type && !r.body.is_empty())
|
||||||
|
.map(|r| r.body.as_slice())
|
||||||
|
}
|
||||||
|
|
||||||
|
/// AACS protection generation a disc carries.
|
||||||
|
///
|
||||||
|
/// The content cert byte distinguishes V10 (`0x00`) from V20 (`0x01`). V21
|
||||||
|
/// cannot be detected from the cert alone — a V21 disc carries a V20 cert
|
||||||
|
/// and is upgraded to `V21` only after the MKB walk turns up the real Variant
|
||||||
|
/// records `0x2d` / `0x2f` (Encrypted Media Key Variant Data and the Variant
|
||||||
|
/// Key Data table).
|
||||||
|
///
|
||||||
|
/// Key-storage stride in `Unit_Key_RO.inf` is 48 bytes for V10 and 64
|
||||||
|
/// bytes for V20 / V21.
|
||||||
|
#[derive(Debug, Clone, Copy, PartialEq, Eq)]
|
||||||
|
pub enum AacsVersion {
|
||||||
|
/// AACS 1.0 — original BD-ROM.
|
||||||
|
V10,
|
||||||
|
/// AACS 2.0 — UHD-BD, classical Media Key derivation.
|
||||||
|
V20,
|
||||||
|
/// AACS 2.1 — UHD-BD with Media Key Variant chain on top of V20.
|
||||||
|
V21,
|
||||||
|
}
|
||||||
|
|
||||||
|
/// AACS major version as the small integer threaded through the scan / key
|
||||||
|
/// paths (`AacsState.version`, `DiscInputs.version`, `DiscInputsCtx::new`):
|
||||||
|
/// 1 = AACS 1.0 (BD), 2 = AACS 2.x (UHD). Centralised so the bare `1`/`2` — and
|
||||||
|
/// the V10-vs-else stride choice it drives — lives in exactly one place.
|
||||||
|
pub const AACS_MAJOR_BD: u8 = 1;
|
||||||
|
|
||||||
|
pub const AACS_MAJOR_UHD: u8 = 2;
|
||||||
|
|
||||||
|
impl AacsVersion {
|
||||||
|
/// Stride (in bytes) between successive encrypted unit keys in
|
||||||
|
/// `Unit_Key_RO.inf`.
|
||||||
|
pub(crate) fn unit_key_stride(self) -> usize {
|
||||||
|
match self {
|
||||||
|
AacsVersion::V10 => 48,
|
||||||
|
AacsVersion::V20 | AacsVersion::V21 => 64,
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
/// This version as the major integer ([`AACS_MAJOR_BD`] / [`AACS_MAJOR_UHD`]).
|
||||||
|
pub fn major(self) -> u8 {
|
||||||
|
match self {
|
||||||
|
AacsVersion::V10 => AACS_MAJOR_BD,
|
||||||
|
AacsVersion::V20 | AacsVersion::V21 => AACS_MAJOR_UHD,
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
/// The version a bare major integer selects for stride purposes: only the
|
||||||
|
/// BD major is V10; every other value takes the V20/V21 64-byte stride.
|
||||||
|
pub fn from_major(major: u8) -> Self {
|
||||||
|
if major == AACS_MAJOR_BD {
|
||||||
|
AacsVersion::V10
|
||||||
|
} else {
|
||||||
|
AacsVersion::V20
|
||||||
|
}
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
/// Find Verify Media Key Record (type 0x81 for AACS 1.0, 0x86 for AACS 2.0/2.1) in MKB.
|
||||||
|
/// 0x81: [C] §3.2.5.1.4. 0x86 (AACS 2.x): [libaacs] `mkb.c` — not in the public spec.
|
||||||
|
pub(crate) fn mkb_find_mk_dv(mkb: &[u8]) -> Option<[u8; 16]> {
|
||||||
|
// Verify-Media-Key record (0x81 for AACS 1.0, 0x86 for AACS 2.x): mk_dv is
|
||||||
|
// the 16 bytes at record offset 4 (body offset 0). Needs rec_len >= 20.
|
||||||
|
let found = mkb_records(mkb).find(|&(_, rt, len)| (rt == 0x81 || rt == 0x86) && len >= 20);
|
||||||
|
match found {
|
||||||
|
Some((o, rec_type, rec_len)) => {
|
||||||
|
let mut dv = [0u8; 16];
|
||||||
|
dv.copy_from_slice(&mkb[o + 4..o + 20]);
|
||||||
|
tracing::debug!(
|
||||||
|
target: "freemkv::disc",
|
||||||
|
phase = "mkb_mk_dv_found",
|
||||||
|
rec_type,
|
||||||
|
pos = o,
|
||||||
|
rec_len,
|
||||||
|
"mk_dv extracted from MKB"
|
||||||
|
);
|
||||||
|
Some(dv)
|
||||||
|
}
|
||||||
|
None => {
|
||||||
|
tracing::warn!(
|
||||||
|
target: "freemkv::disc",
|
||||||
|
phase = "mkb_mk_dv_not_found",
|
||||||
|
"no 0x81/0x86 record with rec_len>=20 found"
|
||||||
|
);
|
||||||
|
None
|
||||||
|
}
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
/// Find Subset-Difference records (type 0x04) in MKB. [C] §3.2.5.1.5.
|
||||||
|
pub(crate) fn mkb_find_subdiff_records(mkb: &[u8]) -> Option<Vec<u8>> {
|
||||||
|
find_record_body(mkb, 0x04)
|
||||||
|
}
|
||||||
|
|
||||||
|
/// Find the Media Key Data Record (cvalues table) in an MKB. [C] §3.2.4 / §3.2.5.1.7.
|
||||||
|
///
|
||||||
|
/// The cvalue table is record type `0x05` (Media Key Data) on BOTH AACS
|
||||||
|
/// 1.0 and AACS 2.x MKBs — its 16-byte cvalue entries are 1:1 with the
|
||||||
|
/// 5-byte Subset-Difference index entries in record `0x04`. This matches
|
||||||
|
/// libaacs, whose `mkb_cvalues()` reads `0x05` and `mkb_subdiff_records()`
|
||||||
|
/// reads `0x04`.
|
||||||
|
///
|
||||||
|
/// On AACS 2.x in-drive UHD MKBs the `0x05` table is large (the full
|
||||||
|
/// subset-difference cvalue set: ~181k entries on a retail MKB, 1:1 with
|
||||||
|
/// the giant `0x04` index), while record `0x07` (Explicit
|
||||||
|
/// Subset-Difference Record) is a much smaller structure (~96 entries) and
|
||||||
|
/// is NOT the cvalue table. An earlier version of this function preferred
|
||||||
|
/// `0x07`, which under-tested the Subset-Difference walk on UHD discs and
|
||||||
|
/// prevented the DK→walk path from ever finding the matching uv. The
|
||||||
|
/// selection MUST therefore be `0x05`-first; `0x07` is only a fallback for
|
||||||
|
/// malformed/legacy MKBs that somehow lack a `0x05` record.
|
||||||
|
pub(crate) fn mkb_find_cvalues(mkb: &[u8]) -> Option<Vec<u8>> {
|
||||||
|
if let Some(body) = find_record_body(mkb, 0x05) {
|
||||||
|
return Some(body);
|
||||||
|
}
|
||||||
|
find_record_body(mkb, 0x07)
|
||||||
|
}
|
||||||
|
|
||||||
|
/// Walk an MKB and return the payload (header stripped) of the first
|
||||||
|
/// record matching `rec_type`. Returns `None` if no such record exists or
|
||||||
|
/// the record is empty.
|
||||||
|
pub(crate) fn find_record_body(mkb: &[u8], rec_type_wanted: u8) -> Option<Vec<u8>> {
|
||||||
|
mkb_records(mkb)
|
||||||
|
.find(|&(_, rt, len)| rt == rec_type_wanted && len > 4)
|
||||||
|
.map(|(o, _, len)| mkb[o + 4..o + len].to_vec())
|
||||||
|
}
|
||||||
|
|
||||||
|
/// Real content length of an MKB: the byte offset where the record stream
|
||||||
|
/// ends. MKB files (especially `MKB_RW.inf`, but `MKB_RO.inf` too on some
|
||||||
|
/// discs) are allocated to a fixed size — often ~128 MiB — with the records at
|
||||||
|
/// the front and the rest zero padding. Walking records (type+len) and stopping
|
||||||
|
/// at the first padding byte (`type == 0` / zero-length / overrun) gives the
|
||||||
|
/// actual size so callers can trim off megabytes of zeros before sending or
|
||||||
|
/// archiving. Returns `mkb.len()` only if the whole buffer parsed as records.
|
||||||
|
pub fn mkb_content_len(mkb: &[u8]) -> usize {
|
||||||
|
// End of the last framed record = where the fixed-region zero padding begins.
|
||||||
|
// (The `00 000000` terminator / overrun stops the walk; real MKBs pad with
|
||||||
|
// zeros, so this matches the prior "stop at the first padding byte".)
|
||||||
|
mkb_records(mkb)
|
||||||
|
.last()
|
||||||
|
.map(|(o, _, len)| o + len)
|
||||||
|
.unwrap_or(0)
|
||||||
|
}
|
||||||
|
|
||||||
|
/// Trim an MKB's trailing fixed-region padding to its real content length —
|
||||||
|
/// but ONLY when [`mkb_content_len`] actually found one. It returns 0 for an
|
||||||
|
/// MKB whose first record cannot be parsed; truncating to 0 in that case would
|
||||||
|
/// hand downstream consumers (and the online key service) an EMPTY MKB that can
|
||||||
|
/// never resolve. So a 0 (or a length that isn't strictly inside the buffer)
|
||||||
|
/// leaves the MKB untouched. A 0.31.0 regression dropped this guard and
|
||||||
|
/// `truncate`-d unconditionally, zeroing unrecognised MKBs.
|
||||||
|
pub fn trim_mkb(mut mkb: Vec<u8>) -> Vec<u8> {
|
||||||
|
let n = mkb_content_len(&mkb);
|
||||||
|
if n > 0 && n < mkb.len() {
|
||||||
|
mkb.truncate(n);
|
||||||
|
}
|
||||||
|
mkb
|
||||||
|
}
|
||||||
|
|
||||||
|
/// Get MKB version from Type and Version Record (type 0x10).
|
||||||
|
/// Layout: 4-byte record header at `pos` (type + BE24 length), then the
|
||||||
|
/// record body starts at `pos + 4`. The body holds the BE u32 Type field at
|
||||||
|
/// body offset 0 (`pos + 4`), then the BE u32 version at body offset 4
|
||||||
|
/// (`pos + 8`).
|
||||||
|
pub fn mkb_version(mkb: &[u8]) -> Option<u32> {
|
||||||
|
// Type-and-Version record (0x10): version is the BE u32 at body offset 4
|
||||||
|
// (record offset 8). Needs rec_len >= 12 (4 header + 4 type + 4 version).
|
||||||
|
mkb_records(mkb)
|
||||||
|
.find(|&(_, rt, len)| rt == 0x10 && len >= 12)
|
||||||
|
.map(|(o, _, _)| u32::from_be_bytes([mkb[o + 8], mkb[o + 9], mkb[o + 10], mkb[o + 11]]))
|
||||||
|
}
|
||||||
|
|
||||||
|
/// `0x00031003` — recordable media MKB (Class I & II compute Km directly).
|
||||||
|
pub const MKB_TYPE_3_RECORDABLE: u32 = 0x0003_1003;
|
||||||
|
|
||||||
|
/// `0x00041003` — AACS 1.0 pre-recorded content MKB (KCD-based). Standard BD.
|
||||||
|
pub const MKB_TYPE_4_PRERECORDED: u32 = 0x0004_1003;
|
||||||
|
|
||||||
|
/// `0x000A1003` — Class II / Unified MKB (Sequence-Key-Block functionality).
|
||||||
|
pub const MKB_TYPE_10_CLASS_II: u32 = 0x000A_1003;
|
||||||
|
|
||||||
|
/// `0x48141003` — AACS 2.0 Category C (UHD content). libaacs `MKB_20_CATEGORY_C`.
|
||||||
|
pub const MKB_20_CATEGORY_C: u32 = 0x4814_1003;
|
||||||
|
|
||||||
|
/// `0x48151003` — AACS 2.1 Category C (UHD content). libaacs `MKB_21_CATEGORY_C`.
|
||||||
|
pub const MKB_21_CATEGORY_C: u32 = 0x4815_1003;
|
||||||
|
|
||||||
|
/// The AACS MKB Type field, decoded.
|
||||||
|
#[derive(Debug, Clone, Copy, PartialEq, Eq)]
|
||||||
|
pub enum MkbType {
|
||||||
|
/// Type 3 — recordable media.
|
||||||
|
Recordable,
|
||||||
|
/// Type 4 — AACS 1.0 pre-recorded content (KCD). Standard Blu-ray.
|
||||||
|
Prerecorded,
|
||||||
|
/// Type 10 — Class II / Unified (SKB).
|
||||||
|
ClassII,
|
||||||
|
/// AACS 2.0 Category C — UHD content.
|
||||||
|
CategoryC20,
|
||||||
|
/// AACS 2.1 Category C — UHD content.
|
||||||
|
CategoryC21,
|
||||||
|
/// Unrecognized MKBType value (raw field preserved).
|
||||||
|
Other(u32),
|
||||||
|
}
|
||||||
|
|
||||||
|
impl MkbType {
|
||||||
|
pub(crate) fn from_raw(raw: u32) -> Self {
|
||||||
|
match raw {
|
||||||
|
MKB_TYPE_3_RECORDABLE => MkbType::Recordable,
|
||||||
|
MKB_TYPE_4_PRERECORDED => MkbType::Prerecorded,
|
||||||
|
MKB_TYPE_10_CLASS_II => MkbType::ClassII,
|
||||||
|
MKB_20_CATEGORY_C => MkbType::CategoryC20,
|
||||||
|
MKB_21_CATEGORY_C => MkbType::CategoryC21,
|
||||||
|
other => MkbType::Other(other),
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
/// AACS generation this MKB belongs to (Category C → 2.0/2.1, else 1.0).
|
||||||
|
pub fn generation(self) -> AacsVersion {
|
||||||
|
match self {
|
||||||
|
MkbType::CategoryC21 => AacsVersion::V21,
|
||||||
|
MkbType::CategoryC20 => AacsVersion::V20,
|
||||||
|
_ => AacsVersion::V10,
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
/// `true` for UHD (AACS 2.x Category C); `false` for Blu-ray (AACS 1.x).
|
||||||
|
pub fn is_uhd(self) -> bool {
|
||||||
|
matches!(self, MkbType::CategoryC20 | MkbType::CategoryC21)
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
/// The raw 32-bit MKBType field from the Type-and-Version record (0x10), bytes
|
||||||
|
/// 4-7. `None` if no 0x10 record is present. [C] §3.2.5.1.1 Table 3-2.
|
||||||
|
pub fn mkb_type_raw(mkb: &[u8]) -> Option<u32> {
|
||||||
|
// Type-and-Version record (0x10): the 32-bit MKBType is bytes 4-7 (body
|
||||||
|
// offset 0). Needs rec_len >= 8 (4 header + 4 type).
|
||||||
|
mkb_records(mkb)
|
||||||
|
.find(|&(_, rt, len)| rt == 0x10 && len >= 8)
|
||||||
|
.map(|(o, _, _)| u32::from_be_bytes([mkb[o + 4], mkb[o + 5], mkb[o + 6], mkb[o + 7]]))
|
||||||
|
}
|
||||||
|
|
||||||
|
/// Decode an MKB's Type field. `None` if no Type-and-Version record is present.
|
||||||
|
pub fn mkb_type(mkb: &[u8]) -> Option<MkbType> {
|
||||||
|
mkb_type_raw(mkb).map(MkbType::from_raw)
|
||||||
|
}
|
||||||
|
|
||||||
|
/// `Some(true)` if this MKB is a UHD (AACS 2.x Category C) block, `Some(false)`
|
||||||
|
/// for Blu-ray (AACS 1.x), `None` if the Type record is absent.
|
||||||
|
pub fn mkb_is_uhd(mkb: &[u8]) -> Option<bool> {
|
||||||
|
mkb_type(mkb).map(MkbType::is_uhd)
|
||||||
|
}
|
||||||
+13
-9
@@ -30,6 +30,7 @@ pub mod content;
|
|||||||
pub mod crypto;
|
pub mod crypto;
|
||||||
pub mod host_certs;
|
pub mod host_certs;
|
||||||
pub mod keys;
|
pub mod keys;
|
||||||
|
pub mod mkb;
|
||||||
pub mod provider;
|
pub mod provider;
|
||||||
pub mod trace;
|
pub mod trace;
|
||||||
pub mod types;
|
pub mod types;
|
||||||
@@ -70,19 +71,22 @@ pub use content::{
|
|||||||
#[doc(hidden)]
|
#[doc(hidden)]
|
||||||
pub use keys::probe;
|
pub use keys::probe;
|
||||||
pub use keys::{
|
pub use keys::{
|
||||||
AACS_MAJOR_BD, AACS_MAJOR_UHD, AacsVersion, ContentCert, MKB_20_CATEGORY_C, MKB_21_CATEGORY_C,
|
ContentCert, ResolveContext, ResolveFailure, ResolvedKeys, UnitKeyFile, decrypt_unit_key,
|
||||||
MKB_TYPE_3_RECORDABLE, MKB_TYPE_4_PRERECORDED, MKB_TYPE_10_CLASS_II, MkbType, ResolveContext,
|
derive_media_key_and_pk_from_dk, derive_media_key_from_dk, derive_media_key_from_pk,
|
||||||
ResolveFailure, ResolvedKeys, UnitKeyFile, decrypt_unit_key, derive_media_key_and_pk_from_dk,
|
derive_vuk, disc_hash, disc_hash_hex, parse_content_cert, parse_unit_key_ro,
|
||||||
derive_media_key_from_dk, derive_media_key_from_pk, derive_vuk, disc_hash, disc_hash_hex,
|
read_mkb_from_drive, recover_dk_position, resolve_keys_v1, resolve_keys_v2, resolve_keys_v21,
|
||||||
mkb_content_len, mkb_is_uhd, mkb_type, mkb_type_raw, mkb_version, parse_content_cert,
|
resolve_keys_with_reason,
|
||||||
parse_unit_key_ro, read_mkb_from_drive, recover_dk_position, resolve_keys_v1, resolve_keys_v2,
|
};
|
||||||
resolve_keys_v21, resolve_keys_with_reason, trim_mkb,
|
pub use mkb::{
|
||||||
|
AACS_MAJOR_BD, AACS_MAJOR_UHD, AacsVersion, MKB_20_CATEGORY_C, MKB_21_CATEGORY_C,
|
||||||
|
MKB_TYPE_3_RECORDABLE, MKB_TYPE_4_PRERECORDED, MKB_TYPE_10_CLASS_II, MkbRecord, MkbType,
|
||||||
|
mkb_content_len, mkb_is_uhd, mkb_type, mkb_type_raw, mkb_version, trim_mkb, walk_mkb,
|
||||||
};
|
};
|
||||||
pub use provider::KeyProvider;
|
pub use provider::KeyProvider;
|
||||||
pub use types::{DeviceKey, DiscEntry, HostCert};
|
pub use types::{DeviceKey, DiscEntry, HostCert};
|
||||||
pub use variant::{
|
pub use variant::{
|
||||||
KEY_CORRECTION_DATA_PLACEHOLDER, MediaKeyVariantError, MkbRecord, ProcessingKeyMatch,
|
KEY_CORRECTION_DATA_PLACEHOLDER, MediaKeyVariantError, ProcessingKeyMatch,
|
||||||
derive_media_key_variant, is_variant_mkb, variant_nonce, walk_mkb, walk_processing_key,
|
derive_media_key_variant, is_variant_mkb, variant_nonce, walk_processing_key,
|
||||||
};
|
};
|
||||||
|
|
||||||
#[cfg(test)]
|
#[cfg(test)]
|
||||||
|
|||||||
+1
-66
@@ -73,6 +73,7 @@
|
|||||||
//! variant path.
|
//! variant path.
|
||||||
|
|
||||||
use super::crypto::{aes_ecb_decrypt, aes_g};
|
use super::crypto::{aes_ecb_decrypt, aes_g};
|
||||||
|
use super::mkb::*;
|
||||||
use super::types::DeviceKey;
|
use super::types::DeviceKey;
|
||||||
|
|
||||||
// ── Public constants ──────────────────────────────────────────────────────
|
// ── Public constants ──────────────────────────────────────────────────────
|
||||||
@@ -86,65 +87,6 @@ pub const KEY_CORRECTION_DATA_PLACEHOLDER: [u8; 16] = [0u8; 16];
|
|||||||
|
|
||||||
// ── MKB record walking ────────────────────────────────────────────────────
|
// ── MKB record walking ────────────────────────────────────────────────────
|
||||||
|
|
||||||
/// A single MKB record produced by [`walk_mkb`].
|
|
||||||
#[derive(Debug, Clone)]
|
|
||||||
pub struct MkbRecord {
|
|
||||||
/// Byte offset of the record within the MKB.
|
|
||||||
pub offset: usize,
|
|
||||||
/// Record type byte.
|
|
||||||
pub rec_type: u8,
|
|
||||||
/// Record length in bytes (includes the 4-byte header).
|
|
||||||
pub rec_len: usize,
|
|
||||||
/// Record body (the bytes after the 4-byte header).
|
|
||||||
pub body: Vec<u8>,
|
|
||||||
}
|
|
||||||
|
|
||||||
/// Walk an MKB into a flat list of records.
|
|
||||||
///
|
|
||||||
/// MKB record framing per AACS: 1 byte type, 3 bytes BE length
|
|
||||||
/// INCLUDING the 4-byte header, followed by payload. The walker stops
|
|
||||||
/// at the first `(type=0, len=0)` end marker or at end of buffer.
|
|
||||||
pub fn walk_mkb(mkb: &[u8]) -> Vec<MkbRecord> {
|
|
||||||
mkb_records(mkb)
|
|
||||||
.map(|(offset, rec_type, rec_len)| MkbRecord {
|
|
||||||
offset,
|
|
||||||
rec_type,
|
|
||||||
rec_len,
|
|
||||||
body: mkb[offset + 4..offset + rec_len].to_vec(),
|
|
||||||
})
|
|
||||||
.collect()
|
|
||||||
}
|
|
||||||
|
|
||||||
/// THE single MKB record-framing walker: yields `(offset, rec_type, rec_len)`
|
|
||||||
/// for each record — a 4-byte header (type byte + big-endian 24-bit length)
|
|
||||||
/// then the body — stopping at the `00 000000` end marker or a
|
|
||||||
/// malformed/out-of-bounds length. Lazy (no body clone), so a find-one-record
|
|
||||||
/// caller never materialises the multi-MB cvalue table. [`walk_mkb`] and every
|
|
||||||
/// MKB record walk in `aacs::keys` are built on this, so the framing rules — and
|
|
||||||
/// any future fix to them — live in exactly one place (they had drifted across
|
|
||||||
/// six hand-rolled copies).
|
|
||||||
pub(crate) fn mkb_records(mkb: &[u8]) -> impl Iterator<Item = (usize, u8, usize)> + '_ {
|
|
||||||
let mut pos = 0usize;
|
|
||||||
std::iter::from_fn(move || {
|
|
||||||
if pos + 4 > mkb.len() {
|
|
||||||
return None;
|
|
||||||
}
|
|
||||||
let rec_type = mkb[pos];
|
|
||||||
let rec_len = ((mkb[pos + 1] as usize) << 16)
|
|
||||||
| ((mkb[pos + 2] as usize) << 8)
|
|
||||||
| (mkb[pos + 3] as usize);
|
|
||||||
if rec_type == 0 && rec_len == 0 {
|
|
||||||
return None;
|
|
||||||
}
|
|
||||||
if rec_len < 4 || pos + rec_len > mkb.len() {
|
|
||||||
return None;
|
|
||||||
}
|
|
||||||
let here = pos;
|
|
||||||
pos += rec_len;
|
|
||||||
Some((here, rec_type, rec_len))
|
|
||||||
})
|
|
||||||
}
|
|
||||||
|
|
||||||
/// True iff `records` contains at least one Media Key Variant record.
|
/// True iff `records` contains at least one Media Key Variant record.
|
||||||
///
|
///
|
||||||
/// The real AACS 2.1 Variant markers — confirmed against a live variant MKB —
|
/// The real AACS 2.1 Variant markers — confirmed against a live variant MKB —
|
||||||
@@ -226,13 +168,6 @@ pub struct ProcessingKeyMatch {
|
|||||||
pub cvalue_index: usize,
|
pub cvalue_index: usize,
|
||||||
}
|
}
|
||||||
|
|
||||||
fn mkb_find_body(records: &[MkbRecord], rec_type: u8) -> Option<&[u8]> {
|
|
||||||
records
|
|
||||||
.iter()
|
|
||||||
.find(|r| r.rec_type == rec_type && !r.body.is_empty())
|
|
||||||
.map(|r| r.body.as_slice())
|
|
||||||
}
|
|
||||||
|
|
||||||
fn mkb_find_mk_dv(records: &[MkbRecord]) -> Option<[u8; 16]> {
|
fn mkb_find_mk_dv(records: &[MkbRecord]) -> Option<[u8; 16]> {
|
||||||
let r = records
|
let r = records
|
||||||
.iter()
|
.iter()
|
||||||
|
|||||||
Reference in New Issue
Block a user