AacsState (public via Disc.aacs) and Key (the decrypt_with key-transport enum)
are crate-root re-exported and carried VUK/unit/read-data keys + volume id on
#[derive(Debug)]; HandshakeResult carried the VID + AACS 2.0 bus key. Manual
Debug impls print shape only, guarded by red->green tests.
These carry raw unit-key / VUK / processing-key bytes on their Debug; manual impls
print shape only (unit_keys_len, redacted markers). Each has a red→green test.
Round-7 findings from the 10-phase release audit (no HIGH; convergence):
- Cap DtsParser.pts_marks (MAX_PTS_MARKS): a run of zero-length timed PES
packets grew no buffer bytes, so the drain_front mark-prune never ran —
the deque could accumulate without bound on hostile PS input.
- detect_disc_format tested HVDVD_TS before BDMV while the title-scan
dispatch tests BDMV first, so a disc with both trees would be classified
HD-DVD but enumerated as Blu-ray. Align both to BDMV → HVDVD_TS →
VIDEO_TS.
- Document why the DTS new-PES re-base can emit a locally-decreasing PTS
(the muxer's block_ts applies the strictly-monotonic audio nudge, tested
in mkv.rs) — this is by design, not a mux defect.
- Fix stale aacs/keys.rs comment references (functions moved to
aacs/inf.rs / aacs::resolve/derive in the module split).
Round-2 findings from the 10-phase release audit:
- parse_vti_clip_order bucketed hits by residue with an O(stride*hits)
rescan and no hit cap, so a crafted HD-DVD VTI packed with millions of
`.EVO` tokens (up to the 64 MiB UDF read cap) could burn seconds of CPU
on a routine scan. Bucket in a single O(hits) pass and cap collected
hits at MAX_VTI_HITS (a real table holds a few dozen).
- Fix the stale `super::keys::…` intra-doc links left by the aacs module
rename: the referenced fns live in `super::derive`.
Round-1 findings from the 10-phase release audit:
- SparsePtsReorder buffered its current GOP with no bound, draining only on
a keyframe — an open-GOP or crafted program stream that never signals one
could hold the whole title in RAM. Force-complete the GOP at
MAX_GOP_FRAMES, matching the MPEG-2 parser's backstop.
- inject_unit_keys labelled a 2.1 FMTS disc as AACS 1.0 / bus-encryption
off; FMTS is UHD-family, so synthesize the UHD version + bus encryption.
- The compiled Key Correction Data was a non-zero 16-byte constant fed into
the Media Key derivation. Per the no-compiled-keys rule it is now all-zero;
the chain still cannot complete on a real disc (documented), so this is
behaviour-neutral — all variant tests pass unchanged.
- Fix stale doc references (broken `super::variants` intra-doc links, and
`aacs::keys` comments) left by the module rename.
Correct the variant Media Key chain against two real variant MKBs
(Zombieland v70, Stand By Me v70): C for Kmp is the per-slot block of
the 0x0c cvalue table indexed by the matched subset-difference, not the
0x2d head. The 0x2d record is the VARIANTS table (leading body-16 bytes,
one big-endian u16 per subset-difference) followed by a trailing 16-byte
Nonce, with no leading header. VKD stays at 0x2f.
Route record-type selection through the named REC_* consts in mkb rather
than bare hex, and document that Key Correction Data is per-licensee: no
universal constant exists and none is compiled in, so on a real disc the
chain yields a wrong Media Key that the Verify-Media-Key gate rejects
rather than emitting a bad key. This is a key-acquisition gap, not a
code gap.
- aacs/resolve: a media-keys-only provider missing the VID classifies as
VidUnavailable, not NoMaterial (an MK derives the VUK once the VID
arrives).
- disc/bluray: mark a clip seen only after its .clpi parses, so a
transient parse failure on the first PlayItem cannot suppress the
clip's extents for a later PlayItem referencing it that succeeds.
- disc/patch: log rather than swallow mapfile record/flush failures on a
reverify downgrade, so a failed persist cannot silently mismark a bad
unit good on resume.
- mux/ts: flag a discontinuity when a partial PES is dropped, matching
the other partial-drop paths.
- mux/demux_thread: the no-demuxer branch forwards an empty batch for
early consumer-disconnect detection instead of reading the whole disc.
- io/pipeline: correct the send-timing log (as_secs_f64, not as_micros
printed as ms).
- aacs/derive, aacs/variant, disc/read_error, keysource: comment/doc
accuracy. sector/prefetched, udf: remove dead fields/functions.
- mux/disc: assert unit-aligned read counts in the test.
Redesign derive_media_key_variant to the minimal derivation surface:
derive_media_key_variant(mkb_records, pk) -> Km
- PK-input only. Deriving Kp from device keys (DK -> PK) is a separate
concern (walk_processing_key); a leaked 2.1 key is a PK, and the chain
starts at Kp. A bare PK arrives without its subset-difference slot, so
the primitive tries it against every slot and returns the Km for the
slot that passes the MKB's Verify-Media-Key record -- mirroring the
classical bare-PK derive_media_key_from_pk, gated by the chain's own
verify so an unverified key is never returned.
- VID-free: the Media Key is MKB-scoped. VUK stays the separate
derive_vuk(Km, VID) step.
- KCD is a fixed algorithm constant compiled in, not a caller parameter
(removes the kcd argument, the placeholder const, and KcdNotProvided).
- Soft-correction / online-challenge slots are treated as non-covering;
surfaced over the generic miss so a disc needing those modes is
distinguishable from a non-covering key.
resolve_keys_v21 updated to walk DK -> PK first, then call the primitive
and derive the VUK from Km + VID. Module + helper docs refreshed to the
pinned record layout; tests reworked for the PK-only signature.
variants_for_uv previously returned None (placeholder), dead-stopping the
Media Key Variant chain at VariantsTableUnavailable on any real disc. Layout
now pinned against two real 2.1 variant MKBs (Zombieland v70, Stand By Me v70):
the 0x2d Encrypted-Media-Key-Variant-Data body is sd_count u16 VARIANTS entries
(1:1 with 0x0c cvalues / 0x04 subset-diffs) followed by the 16-byte per-disc
Nonce at the tail. variants_for_uv reads the sd_slot_index-th u16.
With this the chain runs fully: Kmp -> Kpnew(=Kmp^KCD, extracted CyberLink
constant) -> VKD(0x2f) -> Km -> Kvu. The only remaining input is a covering
2.1 Processing Key to validate against a known answer; until then the final
Verify-Media-Key (0x86) gate rejects any wrong layout pick, so a bad key can
never be emitted. Tests updated to reflect the wired lookup; 1.86 precommit
green (fmt+clippy+tests).
The volume_key module was only 34 lines and is just the tail of the same
DK/PK -> MK -> VUK -> UK derivation ladder as media_key. Fold both into one
derive module so every aacs module is a substantial, distinct responsibility
(crypto/mkb/derive/inf/content/variant/resolve). Relocation only; logic hash
identical (95fb9924); 2210 tests green.
Break the 2800-line keys.rs into four responsibility-scoped modules:
- media_key.rs: DK/PK -> Media Key subset-difference walk (+ probe harness)
- volume_key.rs: VUK derivation, unit-key unwrap
- inf.rs: Unit_Key_RO.inf parsing, disc_hash, content cert, in-drive MKB read
- resolve.rs: the resolve_keys_* orchestration (keys.rs renamed)
Relocation only; the (white-box) test suite stays in resolve.rs and pulls
the moved items via glob imports. Proven byte-identical to the pre-refactor
state via the logic hash (95fb9924); 2210 tests green.
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.
Relocate the shared low-level primitives into a single crypto module:
aes_ecb_encrypt/decrypt, aes_cbc_decrypt, aes_g (from content/variant) and
aesg3 + AESG3_SEED (from keys), plus AACS_IV. Fixes the scatter where AES-G
lived in the 2.1 file and AES-G3 in keys. Relocation only — no rename, no
logic change (logic-hash identical to baseline; 277 items; 2210 tests green).
Pure file+module-path rename. 'content' names the AACS unit-decrypt layer
(distinct from the top-level sector-decrypt driver crate::decrypt), and
'variant' (singular, spec term 'Media Key Variant') names the 2.1 chain.
Logic-hash identical to baseline; 277 items intact; tests green.
Matthew Jackson