aacs: KeyProvider abstraction + PK walker + external-UK key source
Two coherent additions to the AACS resolver: KeyProvider abstraction (provider.rs) — key material comes from pluggable backends; KeyDb implements it (device/processing keys, host certs, disc-by-hash / disc-by-vid lookup) plus orphan-DK parsing. ResolveContext takes a provider array. Adds the SD-tree PK walker (derive_media_key_from_pk_walked) and a `probe` module (km_verifies MK oracle, mkb_* record parsers) used for offline key verification. Cvalue record selection prefers 0x05, falls back to 0x07. External-UK key source — the second, mutually-exclusive key source for the keyserver path. ScanOptions/InputOptions gain `unit_key`; when set, resolve_encryption_static skips keydb entirely and uses the caller-supplied Unit Key directly (KeySource::ExternalUk). Disc::read_aacs_inputs exposes a disc's Unit_Key_RO.inf + MKB so a caller can fetch the UK out-of-band; the library makes no network call itself. CHANGELOG: redact test-disc title in historical notes.
This commit is contained in:
MattJackson
+65
-2
@@ -236,7 +236,7 @@ impl Disc {
|
||||
// optical drives) responds by entering a fast-fail firmware
|
||||
// wedge state where every subsequent CDB returns
|
||||
// ILLEGAL_REQUEST/INVALID_FIELD_IN_CDB (sense 05/24) until
|
||||
// power-cycled. Hit live on rip1 2026-05-20 during a Barbie
|
||||
// power-cycled. Hit live on rip1 2026-05-20 during a MOVIE
|
||||
// UHD scan: KEYDB miss → 16 cert attempts in a tight loop →
|
||||
// wedge → forced host reboot + drive disconnect to recover.
|
||||
//
|
||||
@@ -424,11 +424,12 @@ impl Disc {
|
||||
Some(s) => s,
|
||||
None => return Err(miss_error),
|
||||
};
|
||||
let providers: &[&dyn aacs::KeyProvider] = &[&keydb];
|
||||
let aacs_ctx = aacs::ResolveContext {
|
||||
unit_key_ro: &uk_ro_data,
|
||||
content_cert: cc_data.as_deref(),
|
||||
volume_id: &volume_id,
|
||||
keydb: &keydb,
|
||||
providers,
|
||||
mkb: mkb_data.as_deref(),
|
||||
};
|
||||
let mut ctx = DrmContext {
|
||||
@@ -466,4 +467,66 @@ impl Disc {
|
||||
volume_id,
|
||||
})
|
||||
}
|
||||
|
||||
/// Resolve encryption from a caller-supplied Unit Key (the keyserver
|
||||
/// path). No keydb, no derivation: read `Unit_Key_RO.inf` for the disc
|
||||
/// hash + version/bus-encryption flags, then use `unit_key` directly as
|
||||
/// CPS unit 1's decryption key. The handshake (if any) still supplies the
|
||||
/// volume ID and AACS 2.0 read-data key for bus decryption.
|
||||
pub(super) fn resolve_encryption_static(
|
||||
udf_fs: &udf::UdfFs,
|
||||
reader: &mut dyn SectorSource,
|
||||
unit_key: [u8; 16],
|
||||
handshake: Option<&HandshakeResult>,
|
||||
) -> Result<AacsState> {
|
||||
use crate::aacs;
|
||||
|
||||
let uk_ro_data = udf_fs
|
||||
.read_file(reader, "/AACS/Unit_Key_RO.inf")
|
||||
.or_else(|_| udf_fs.read_file(reader, "/AACS/DUPLICATE/Unit_Key_RO.inf"))
|
||||
.map_err(|_| Error::AacsNoKeys)?;
|
||||
let dh = aacs::disc_hash(&uk_ro_data);
|
||||
|
||||
let cc = udf_fs
|
||||
.read_file(reader, "/AACS/Content000.cer")
|
||||
.or_else(|_| udf_fs.read_file(reader, "/AACS/Content001.cer"))
|
||||
.ok()
|
||||
.as_deref()
|
||||
.and_then(aacs::parse_content_cert);
|
||||
let bus_encryption = cc.as_ref().map(|c| c.bus_encryption).unwrap_or(false);
|
||||
let version = match cc.as_ref().map(|c| c.version) {
|
||||
Some(aacs::AacsVersion::V10) => 1,
|
||||
Some(_) => 2,
|
||||
None if bus_encryption => 2,
|
||||
None => 1,
|
||||
};
|
||||
|
||||
let mkb_ver = udf_fs
|
||||
.read_file(reader, "/AACS/MKB_RW.inf")
|
||||
.or_else(|_| udf_fs.read_file(reader, "/AACS/MKB_RO.inf"))
|
||||
.ok()
|
||||
.as_deref()
|
||||
.and_then(aacs::mkb_version);
|
||||
|
||||
tracing::warn!(
|
||||
target: "freemkv::disc",
|
||||
phase = "scan_aacs_external_uk",
|
||||
disc_hash = %aacs::disc_hash_hex(&dh),
|
||||
version,
|
||||
bus_encryption,
|
||||
"using caller-supplied unit key (keyserver path)"
|
||||
);
|
||||
|
||||
Ok(AacsState {
|
||||
version,
|
||||
bus_encryption,
|
||||
mkb_version: mkb_ver,
|
||||
disc_hash: aacs::disc_hash_hex(&dh),
|
||||
key_source: KeySource::ExternalUk,
|
||||
vuk: None,
|
||||
unit_keys: vec![(1, unit_key)],
|
||||
read_data_key: handshake.and_then(|h| h.read_data_key),
|
||||
volume_id: handshake.map(|h| h.volume_id).unwrap_or([0u8; 16]),
|
||||
})
|
||||
}
|
||||
}
|
||||
|
||||
+41
-3
@@ -912,6 +912,9 @@ pub enum KeySource {
|
||||
/// Pre-decrypted unit keys taken directly from KEYDB by disc hash.
|
||||
/// No VUK present in the entry — `AacsState::vuk` is `None`.
|
||||
KeyDbUnitKeys,
|
||||
/// Unit key supplied directly by the caller (the keyserver path).
|
||||
/// No keydb, no derivation — `AacsState::vuk` is `None`.
|
||||
ExternalUk,
|
||||
}
|
||||
|
||||
impl KeySource {
|
||||
@@ -922,6 +925,7 @@ impl KeySource {
|
||||
KeySource::KeyDbDerived => "KEYDB (derived)",
|
||||
KeySource::KeyDb => "KEYDB",
|
||||
KeySource::KeyDbUnitKeys => "KEYDB (unit keys)",
|
||||
KeySource::ExternalUk => "external UK",
|
||||
}
|
||||
}
|
||||
}
|
||||
@@ -941,6 +945,13 @@ pub struct ScanOptions {
|
||||
/// Path to KEYDB.cfg for AACS key lookup.
|
||||
/// If None, searches standard locations ($HOME/.config/aacs/ and /etc/aacs/).
|
||||
pub keydb_path: Option<std::path::PathBuf>,
|
||||
/// Caller-supplied Unit Key — the second, mutually-exclusive key source
|
||||
/// (the online-keyserver path). When set, libfreemkv skips keydb lookup
|
||||
/// and all derivation and uses this key directly to decrypt. Takes
|
||||
/// precedence over `keydb_path` if both are set. The caller obtains it
|
||||
/// however it likes (e.g. POSTing the disc's `Unit_Key_RO.inf` + MKB to a
|
||||
/// keyserver); libfreemkv stays free of any network dependency.
|
||||
pub unit_key: Option<[u8; 16]>,
|
||||
}
|
||||
|
||||
impl ScanOptions {
|
||||
@@ -1140,6 +1151,26 @@ impl Disc {
|
||||
Self::scan_with(reader, capacity, None, None, opts, udf_fs)
|
||||
}
|
||||
|
||||
/// Read a disc's AACS key-input files from an ISO image: returns
|
||||
/// `(Unit_Key_RO.inf, MKB)` raw bytes. For callers that resolve keys
|
||||
/// out-of-band (the keyserver path) — POST these to the keyserver, get the
|
||||
/// Unit Key, then scan with `ScanOptions { unit_key: Some(uk), .. }`.
|
||||
/// libfreemkv itself never makes the network call.
|
||||
pub fn read_aacs_inputs(iso_path: &std::path::Path) -> Result<(Vec<u8>, Vec<u8>)> {
|
||||
let mut reader = crate::io::file_sector_source::FileSectorSource::open(iso_path)
|
||||
.map_err(|_| Error::AacsNoKeys)?;
|
||||
let udf_fs = udf::read_filesystem(&mut reader)?;
|
||||
let inf = udf_fs
|
||||
.read_file(&mut reader, "/AACS/Unit_Key_RO.inf")
|
||||
.or_else(|_| udf_fs.read_file(&mut reader, "/AACS/DUPLICATE/Unit_Key_RO.inf"))
|
||||
.map_err(|_| Error::AacsNoKeys)?;
|
||||
let mkb = udf_fs
|
||||
.read_file(&mut reader, "/AACS/MKB_RW.inf")
|
||||
.or_else(|_| udf_fs.read_file(&mut reader, "/AACS/MKB_RO.inf"))
|
||||
.map_err(|_| Error::AacsNoKeys)?;
|
||||
Ok((inf, mkb))
|
||||
}
|
||||
|
||||
/// Core scan pipeline — works with any SectorSource.
|
||||
///
|
||||
/// `handshake_error` is plumbed from `do_handshake` so failures
|
||||
@@ -1159,7 +1190,16 @@ impl Disc {
|
||||
let encrypted =
|
||||
udf_fs.find_dir("/AACS").is_some() || udf_fs.find_dir("/BDMV/AACS").is_some();
|
||||
|
||||
let (aacs, aacs_error) = if encrypted {
|
||||
let (aacs, aacs_error) = if !encrypted {
|
||||
(None, None)
|
||||
} else if let Some(unit_key) = opts.unit_key {
|
||||
// Second key source: caller supplied the Unit Key directly
|
||||
// (keyserver path). Skip keydb entirely.
|
||||
match Self::resolve_encryption_static(&udf_fs, reader, unit_key, handshake.as_ref()) {
|
||||
Ok(state) => (Some(state), None),
|
||||
Err(e) => (None, Some(e)),
|
||||
}
|
||||
} else {
|
||||
match opts.resolve_keydb() {
|
||||
Some(keydb_path) => {
|
||||
match Self::resolve_encryption(&udf_fs, reader, &keydb_path, handshake.as_ref())
|
||||
@@ -1207,8 +1247,6 @@ impl Disc {
|
||||
(None, Some(final_err))
|
||||
}
|
||||
}
|
||||
} else {
|
||||
(None, None)
|
||||
};
|
||||
|
||||
// 3. Titles — BD (MPLS playlists) or DVD (IFO title sets)
|
||||
|
||||
Reference in New Issue
Block a user