Move the encrypted sample reader and the key-resolution loop into libfreemkv
(they read the disc and validate keys — decryption mechanism, not lookup). A
key source now only looks a key up and hands it back.
Each source implements next_key (a cursor over its candidates) instead of
returning them all at once. The keydb hands its per-disc candidates out
UK-first (UK > VK > MK > DK) so a stale/wrong VUK never pre-empts a good UK in
the same entry; online and mapfile are one-shot. MultiSource composes sources
in the caller's chosen order and resolve_and_apply drives the
next_key -> decrypt_with loop, stopping at the first key that decrypts.
read_sample_units moves here so the CLI and autorip share one content sampler.
OnlineSource: the remote key-service client (moved out of autorip), posting the
disc's Unit_Key_RO.inf + MKB + Volume ID + encrypted content samples to the
service and returning the resolved unit key as a terminal Key::Unit candidate.
Kept out of libfreemkv so the library stays network-free. Source-internal
failures (unreachable / status / parse) are logged and surface as "no
candidate" so the next source is tried.
MapfileSource: reads a rip mapfile's persisted unit keys (the resume / deferred-
mux fast path) and offers them as a Key::Unit candidate. Keyed by mapfile path.
DiscInputs gained an app-populated `samples` field for sources that validate
against ciphertext server-side (OnlineSource); local sources ignore it.
The published key-source layer for libfreemkv. libfreemkv does no lookup; it
is handed a Key and derives down. This crate provides the KeySource impls that
do the lookup and hand a Key in. Applications choose and order the sources.
This first cut ships:
- KeydbSource: parses a local keydb.cfg and enumerates its material as ordered
candidate keys (per-disc VUK/unit/media first, then the universal device-key,
processing-key, and media-key pools). It does no derivation — the library
walks the MKB and verifies media keys. Candidate ordering lets the library
try each path a keydb can satisfy.
- resolve_first: tries each source's candidates in order and returns the first
the caller's validator accepts (validate-before-return), so a stale entry
falls through to the next source.
OnlineSource (remote key service) and MapfileSource (cached unit key) land with
the application wiring, where the sample-read and mapfile paths already live.
Matthew Jackson