Two problems, both invisible until the whole graph is looked at together.
DEAD: num-bigint, sha2, num-traits, num-integer, cmac and cbc are
declared here and referenced nowhere -- not in src, tests or benches.
They were being compiled, audited and offered version bumps forever for
no reason. Removing beats bumping.
cbc nearly survived the sweep: a substring search for "cbc" matches 44
occurrences of ycbcr_to_rgb in the DVD subtitle decoder, so it looked
used. Only a word-boundary search exposed it.
SKEW: this crate was the outlier on every shared dependency -- aes 0.8,
rand 0.8, base64 0.22.1 and zip 2 against 0.9 / 0.10 / 0.23 / 8
elsewhere. Cargo cannot unify across a major version, so it compiled
BOTH: 32 duplicated crates in the freemkv binary's graph, including two
complete AES implementations (aes 0.8 + 0.9, cipher 0.4 + 0.5), two
digest stacks and two getrandom. Two crypto stacks in one product is
worth removing on its own.
The aes bump is an API rename -- BlockCipher-prefixed traits, Array for
GenericArray -- and the obvious translation uses Array::from_slice,
which the new version deprecates and clippy's -D warnings would reject.
These use the From<[T; N]> conversion the crate points at instead.
3441 tests pass in debug and release. The AACS crypto here is covered by
known-answer tests, so a byte-order or sizing mistake in that rename
could not have passed.
descramble_region was fixed to require the MPEG-2 pack start code, but
descramble_sector — the PUBLIC per-sector entry point, and the one the
module-level example tells callers to use — still keyed on the byte 0x14 flag
bits alone. The crate own documented guidance therefore led straight back into
the defect this release exists to fix: a VIDEO_TS.IFO sector holding 0x15 at
0x14 while starting 00 26 00 00 loses 1912 of its 2048 bytes, and because that
sector carries TT_SRPT the disc enumerates 38 titles while an image decrypted
from it enumerates 10, at exit 0.
It has no callers inside the crate, which is exactly why it survived three
rounds: nothing exercised it. Putting the guard inside the function rather than
in each caller is what keeps the safe path the easy one.
The integration test that covers it built its sector from the flag byte alone,
which no real scrambled sector looks like, so it stopped representing the path
it names — the same fixture-realism gap already fixed in four other places this
release.
The 1.6.1 DVD fix removed the USE of the loose predicate but left the
predicate sitting there with the better name. Anyone asking "is this sector
scrambled?" finds is_scrambled before is_scrambled_pack, and reintroduces the
defect that destroyed 1912 bytes of a real VIDEO_TS.IFO — the sector carrying
TT_SRPT — so the disc enumerated 38 titles and an image decrypted from it
enumerated 10, silently, at exit 0.
Byte 0x14 only means "scrambling control" inside an MPEG-2 pack. In an IFO,
UDF or ISO 9660 sector it is whatever that format stores there. The new name
says what the function actually tests and nothing more, so the honest question
has the obvious name and the dangerous one has to be asked for deliberately.
Its doc comment also claimed a caller, decrypt::decrypt_sectors, that does not
exist — so the name was an invitation and the documentation was an argument
for accepting it. It has no production callers at all; it stays public because
an integration test asserts the flag extraction directly.
The keyserver protocol now returns all 32 index keys as an array for a
forensic content sample (and a single-element array for plain content).
resolve_fmts_key_map sends one forensic batch and maps array element i to
segment index i+1, replacing the per-index blind-probe collection loop
that repeatedly hit the key service. Segment/index parsing and the
aligned-unit content classification are reworked to support this:
- rename variant_select -> index_select (per-index, not per-variant)
- content classification moves to is_clean(buf, ContentFormat) so the
unit selector emits only units the key service accepts
- segment.rs: parse IndividualSegment.tbl index tags + SPN ranges,
build contiguous LBA key ranges from the resolved 32-key array
- decrypt/decorator plumbing for the resolved per-index keys
Fail loud (FmtsKeyMissing) when the forensic query returns < 32 keys or
any segment index stays unresolved.
decrypt:
- decrypt_sectors is now a pure decrypt (apply key, leave plaintext, report
unverified bytes); TS-structure is a separate primitive (is_clean_ts/ps) used
only for key selection and read-verify. The mux passes decrypted bytes through
(the demuxer drops non-conforming packets), ending the NULL-TS conceal loop and
the per-unit key-server refetch storm. Key-proof floor replaces the 75%
supermajority.
recovery:
- Removed the post-read decrypt-verify gate (verify.rs) that mis-aligned the
disc-absolute unit grid against clip-anchored AACS units and false-failed good
clips (e.g. Dunkirk's orphan-CPS clip). Bad sectors are marked by physical read
result; decryptability is proven at scan + mux time.
HD DVD (first-class AACS):
- Role-based candidate-list file sourcing so an HD DVD's /ANY!/ files
(MKBROM.AACS, VTKF000.AACS, CONTENT_CERT.AACS) are found with no disc-type
branch. parse_vtkf parses VTKF000.AACS into the same UnitKeyFile as a BD
Unit_Key_RO.inf, so the shared VUK unwrap applies unchanged. set_unit_base
clip-anchoring. Two decrypt-axis assumptions remain UNVERIFIED-HDDVD-DECRYPT
(no encrypted disc to test).
mux:
- MVC (Blu-ray 3D) track signals unified into one MVCDecoderConfigurationRecord;
release-safe track_vint (3-byte VINT) and pid_index (i32) guards.
hardening:
- Container-aware is_clean / encryption detection; bytes_bad_in_title fail-safe
on a corrupt mapfile; CSS crack gated on DiscFormat::Dvd (HD DVD excluded);
non-vacuous CSS tests; patch NOT_READY/HARDWARE/ILLEGAL_REQUEST/ABORTED
sense-path tests.
The facade removal (5ff0464) left tests/ calling aacs::disc_hash,
aacs::decrypt_unit, aacs::AacsVersion, etc. at the old flat paths,
so the branch did not compile its integration tests. Repoint each
to its real module (inf/derive/content/mkb). No logic change.
Post-read verify gate (new src/disc/verify.rs): UnitVerifier buffers/aligns the disc-absolute read stream into clip-file 6144-byte units, then makes one decryptability() decision per unit (CPI gate -> held keys -> key_fetch -> strict TS). POST_READ_VERIFY const kill-switch; fail-safe contract (only ever downgrades units it is confident are undecryptable; every doubt skips). Hooked into Disc::sweep (producer observes ciphertext -> WorkItem::MarkBad after the Good, FIFO-ordered) and Disc::patch (post-loop reverify_iso reads recovered units whole from the patched ISO). extract::clip_layouts enumerates AACS clips for the gate.
Standards-correct AACS verify: aacs::unit_is_clean_ts is a strict port of libaacs _verify_ts (all 32 TS syncs, not a majority vote); decrypt_unit accepts a key only on it; the majority verify_ts is removed. Deleted the Disc::verify_clips post-pass bolt-on (its primitive is absorbed by the read-path gate).
libaacs/DVD audit fixes: content-cert bus_encryption flag now read from bit 7 (was bit 0 - defeated the bus-key fail-loud gate); cc_id read from offset 14; title_cps_unit range-validated + 1->0 index-converted per libaacs. Corrected attack_crib ("functionally-equivalent" not "exact" port) and read_disc_key (READ DVD STRUCTURE 0xAD, not REPORT KEY) doc comments.
Also includes accumulated uncommitted work: key-fetch seam and TrueHD/DTS audio fix.
Rename is_unit_encrypted -> is_aacs_scrambled and decide encryption from the unit's MPEG-TS sync bytes (destroyed by the encrypted body) instead of the TP_extra copy-control (byte 0) or TS scrambling-control (byte 7) flags, which discs do not set reliably. One shared predicate now backs the decrypt gate and out-of-band key validation, so callers agree on what 'encrypted' means. Decryption restores the syncs, so a decrypted unit reads as clear and there is no flag to clear.
is_unit_encrypted read the TP_extra copy-control bits (byte 0), which are a
copy-permission flag, not an encryption flag. On discs whose sampled units are
clear navigation packets (PAT/PMT) those bits can be set while the unit is not
scrambled, so a correct Unit Key was used to 'decrypt' already-plaintext data,
produced garbage, and the key was wrongly treated as failing.
Read the actual flag instead: the TS transport_scrambling_control bits (top two
of TS-header byte 3 = byte 7 of the aligned unit, inside the clear seed). AACS
encrypts whole aligned units, so this one packet's TSC reflects the unit.
decrypt_unit now clears the TSC bits of every packet on the way out so the
result is valid unscrambled TS. Tests updated to the TSC flag.
- Introduce DrmScheme enum (Css/Aacs10/Aacs20/Aacs21) + drm module with
uniform detect/load dispatch across all four protection schemes.
- Land AACS 2.1 Media Key Variant framework in aacs::variants: chain
derivation, MKB record types 0x82/0x83, bit-0x02 SoftKCD and bit-0x04
online-challenge detection. Aacs21 dispatcher arm wired but commented
out pending validation against a Variant-scheme disc.
- Replace aacs2: bool with AacsVersion enum across ContentCertificate,
UnitKeyFile, ResolvedKeys. resolve_keys splits into _v1/_v2/_v21.
- Delete the libredrive raw-read VID shortcut from do_handshake; the
drive enforces the AGID requirement regardless of firmware-upload
state, so the shortcut spuriously dispatched E7017 instead of
surfacing the real downstream walls.
Audit pass against the project docs "no English text in library code" rule.
Found 9 call sites that violated the contract by stuffing English into
io::Error::new(kind, "…") or by abusing Error::DeviceNotFound { path }
as a free-form description field. Each is now a typed Error variant.
New variants and codes: ScsiInterfaceUnavailable (E1004), DeviceLocked
(E1005), IoKitPluginFailed (E1006), UnsupportedPlatform (E2003),
PlatformNotImplemented (E2004), MapfileInvalid (E6011), DiscUrlNotDirect
(E9009).
labels::apply() previously pushed Commentary/Descriptive/Score/IME and
" (Secondary)" English literals into AudioStream.label, leaking into
MKV titles + autorip UI. AudioStream now exposes structured `purpose:
LabelPurpose`, SubtitleStream `qualifier: LabelQualifier`. Callers
translate to localized text. label keeps codec-formatting only.
API hygiene: 11 mux/* modules dropped from `pub` to `pub(crate)` —
their *types* are still re-exported from lib.rs, but the modules were
leaking low-level EBML/TS/network primitives. Stream trait gets a real
rustdoc explaining read-vs-write split. lib.rs grouped re-exports into
documented sections. ScanOptions::with_keydb() removed (one-method-per-
action rule); use struct literal.
Dead-code sweep: removed lookahead.rs (orphan, never declared as mod),
tsreader.rs (TsDemuxReader unused), ebml::{write_int,read_vint,SEEK_*},
ts::{scan_first/last_pts,scan_duration,SCAN_HEAD/TAIL_SIZE,take/set_
remainder}, MkvMuxer codec_private_slots/filled fields and
fill_codec_private method (deferred-codecPrivate path never used since
the v0.10 PES rewrite). cargo clippy --all-targets -D warnings clean.
Tests: new error::tests for variant codes + Display "no English" guard +
io::ErrorKind mapping. 233 lib tests, all green (was 230).
Breaking: ScanOptions::with_keydb removed; mux/* modules pub(crate);
AudioStream and SubtitleStream gained required fields; UnsupportedDrive
{ product_revision: "Renesas not yet implemented" } no longer produced
(use PlatformNotImplemented).
- DVD PS path now calls parser.parse() like BD-TS path does
- MPEG-2 sequence headers extracted for codec_private
- Keyframe detection from parser instead of always-true
- Fix CSS roundtrip tests: descramble uses TAB1 permutation, not pure XOR
Stream trait: read() returns PesFrame, write() accepts PesFrame.
A stream is a stream — you read from it or write to it.
No separate Input/Output traits.
API: libfreemkv::input(url) and libfreemkv::output(url, title, codecs)
Returns Box<dyn Stream>.
Matthew Jackson