v1.6.0: bump version (unified release)

The fvi provenance fix, the key-service outage codes, the settings BOM
data-loss fix and the per-track-kind picker rows all landed on dev without a
changelog line. A release that ships undocumented fixes is one nobody can
audit later.

.github/workflows/ci.yml

@@ -2,35 +2,172 @@ name: CI
 
 on:
   push:
-    branches: [main]
+    # `dev` is where work lands and where CI must be green. `main` only ever
+    # moves at release time, to the tagged commit, so a push to it is the
+    # release validation run rather than day-to-day feedback.
+    branches: [main, dev]
   pull_request:
 
-# freemkv-keysources depends on libfreemkv from crates.io (see Cargo.toml).
-# No sibling-repo checkout is needed.
+# WHY THE SIBLING CHECKOUTS — this is NOT a monorepo.
+#
+# The committed Cargo.toml resolves libfreemkv from a git TAG (it is off
+# crates.io). That means CI was building this branch against the LAST RELEASE
+# of libfreemkv, never against libfreemkv's dev tip — so a coordinated change
+# across the two repos could not be verified until release.sh cut the tags.
+# Green here meant "compiles against last month's library".
+#
+# The fix mirrors the developer's local layout. Every repo is checked out into
+# a subdirectory of $GITHUB_WORKSPACE, reproducing
+# ~/Developer/freemkv/{freemkv-keysources,libfreemkv,freemkv-unlock}, and a
+# generated .cargo/config.toml redirects the git-tag patch to those paths.
+# Config-level [patch.crates-io] wins over the manifest one, which is the same
+# mechanism local development already uses (see the note in Cargo.toml).
+#
+# Subdirectories rather than `../libfreemkv` because actions/checkout refuses
+# any `path:` outside $GITHUB_WORKSPACE, and the workspace IS the repo dir.
+# Repos stay separate, tags stay separate, the release cascade is untouched.
+#
+# libfreemkv path-deps ../freemkv-unlock, which resolves to the workspace root
+# under this layout — hence the third checkout.
+#
+# `--locked` is deliberately absent: Cargo.lock is gitignored here (library
+# convention), so there is nothing to lock against and it fails rather than
+# resolves. That is what was breaking this workflow. The lock that has to hold
+# is the one release.sh regenerates in each consuming binary.
 
 jobs:
   lint:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v5
-      - uses: dtolnay/rust-toolchain@1.86.0
+        with:
+          path: freemkv-keysources
+      - uses: actions/checkout@v5
+        with:
+          repository: freemkv/libfreemkv
+          ref: dev
+          path: libfreemkv
+      - uses: actions/checkout@v5
+        with:
+          repository: freemkv/freemkv-unlock
+          ref: dev
+          path: freemkv-unlock
+      - name: Resolve siblings from their dev tips
+        shell: bash
+        working-directory: freemkv-keysources
+        run: |
+          mkdir -p .cargo
+          cat > .cargo/config.toml <<'EOF'
+          [patch.crates-io]
+          libfreemkv = { path = "../libfreemkv" }
+          EOF
+      - uses: dtolnay/rust-toolchain@1.97.0
         with:
           components: clippy, rustfmt
-      # Cache ~/.cargo/registry + target/ across runs. Saves ~30-60s
-      # of crates.io index download per job; incremental compilation
-      # helps on re-runs that don't bump Cargo.lock.
       - uses: Swatinem/rust-cache@v2
         with:
-          shared-key: freemkv-keysources-ci
+          workspaces: freemkv-keysources
       - run: cargo fmt --check
-      - run: cargo clippy -- -D warnings
+        working-directory: freemkv-keysources
+      # --all-targets so the test code is linted too, not just the library.
+      - run: cargo clippy --all-targets -- -D warnings
+        working-directory: freemkv-keysources
 
   test:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v5
-      - uses: dtolnay/rust-toolchain@1.86.0
+        with:
+          path: freemkv-keysources
+      - uses: actions/checkout@v5
+        with:
+          repository: freemkv/libfreemkv
+          ref: dev
+          path: libfreemkv
+      - uses: actions/checkout@v5
+        with:
+          repository: freemkv/freemkv-unlock
+          ref: dev
+          path: freemkv-unlock
+      - name: Resolve siblings from their dev tips
+        shell: bash
+        working-directory: freemkv-keysources
+        run: |
+          mkdir -p .cargo
+          cat > .cargo/config.toml <<'EOF'
+          [patch.crates-io]
+          libfreemkv = { path = "../libfreemkv" }
+          EOF
+      - uses: dtolnay/rust-toolchain@1.97.0
       - uses: Swatinem/rust-cache@v2
         with:
-          shared-key: freemkv-keysources-ci
-      - run: cargo test --locked
+          workspaces: freemkv-keysources
+      - run: cargo test --tests
+        working-directory: freemkv-keysources
+
+  # This crate ships wherever freemkv and autorip ship, and it drags in all of
+  # libfreemkv's platform code (SCSI transports included). Build the tests, not
+  # `cargo check` — check skips codegen and never compiles test-only code.
+  check-macos:
+    runs-on: macos-latest
+    steps:
+      - uses: actions/checkout@v5
+        with:
+          path: freemkv-keysources
+      - uses: actions/checkout@v5
+        with:
+          repository: freemkv/libfreemkv
+          ref: dev
+          path: libfreemkv
+      - uses: actions/checkout@v5
+        with:
+          repository: freemkv/freemkv-unlock
+          ref: dev
+          path: freemkv-unlock
+      - name: Resolve siblings from their dev tips
+        shell: bash
+        working-directory: freemkv-keysources
+        run: |
+          mkdir -p .cargo
+          cat > .cargo/config.toml <<'EOF'
+          [patch.crates-io]
+          libfreemkv = { path = "../libfreemkv" }
+          EOF
+      - uses: dtolnay/rust-toolchain@1.97.0
+      - uses: Swatinem/rust-cache@v2
+        with:
+          workspaces: freemkv-keysources
+      - run: cargo build --tests
+        working-directory: freemkv-keysources
+
+  check-windows:
+    runs-on: windows-latest
+    steps:
+      - uses: actions/checkout@v5
+        with:
+          path: freemkv-keysources
+      - uses: actions/checkout@v5
+        with:
+          repository: freemkv/libfreemkv
+          ref: dev
+          path: libfreemkv
+      - uses: actions/checkout@v5
+        with:
+          repository: freemkv/freemkv-unlock
+          ref: dev
+          path: freemkv-unlock
+      - name: Resolve siblings from their dev tips
+        shell: bash
+        working-directory: freemkv-keysources
+        run: |
+          mkdir -p .cargo
+          cat > .cargo/config.toml <<'EOF'
+          [patch.crates-io]
+          libfreemkv = { path = "../libfreemkv" }
+          EOF
+      - uses: dtolnay/rust-toolchain@1.97.0
+      - uses: Swatinem/rust-cache@v2
+        with:
+          workspaces: freemkv-keysources
+      - run: cargo build --tests
+        working-directory: freemkv-keysources

.github/workflows/release.yml

@@ -36,7 +36,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v5
-      - uses: dtolnay/rust-toolchain@1.86.0
+      - uses: dtolnay/rust-toolchain@1.97.0
       - uses: Swatinem/rust-cache@v2
       - run: cargo test
 

CHANGELOG.md

@@ -1,5 +1,58 @@
 # Changelog
 
+## [1.6.0] — 2026-08-03
+
+### Fixed
+
+- **Key-service failures are no longer indistinguishable from "no key for this
+  disc".** `query` returned an empty vector for a 502, a 401, a 429, a
+  transport error and an unparseable body alike — the same value a successful
+  lookup with no match returns. It now returns a typed error, and the HTTP
+  status is classified into the operator action it implies: 401/403 the token,
+  429 back off, any other non-2xx the service. A genuine miss is a 200 with no
+  key, so every non-2xx is a failure by definition. A DNS failure or timeout
+  now counts as unreachable rather than as a bad URL.
+
+Version sync with the workspace (freemkv-engine split release). No source change
+in this crate; it remains a pluggable AACS key-source provider consumed by the
+`freemkv` CLI and libfreemkv's key resolver.
+
+## [1.5.2] — 2026-07-22
+
+Version sync with the workspace; inherits libfreemkv 1.5.2 (CSS DVD descramble
+fix). No source change in this crate.
+
+## [1.4.5] — 2026-07-18
+
+Version sync; inherits libfreemkv 1.4.5. `KeySource` split into `get_unit_keys` +
+`get_fmts_indexes`, and a keydb device-key parse bug on an uppercase `0X` hex
+prefix was fixed (case-insensitive hex parsing across the toolchain).
+
+## [1.4.4] — 2026-07-17
+
+Version sync; inherits libfreemkv 1.4.4. The online `/decode` request is built from
+a `DecodeSampleSet` proven sufficient by type rather than a runtime length check.
+
+## [1.4.3] — 2026-07-17
+
+Version sync; inherits libfreemkv 1.4.3. The online unit-key reply is parsed as a
+list (one key for an ordinary disc, the ordered set for a forensic-variant disc),
+and `MIN_SAMPLE_UNITS` is re-exported from libfreemkv.
+
+## [1.4.2] — 2026-07-15
+
+Version sync with the workspace; inherits libfreemkv 1.4.2. The keydb test that
+feeds real key material into the AACS crypto was adapted to the segregated
+`decrypt_unit` + `is_clean` primitives (behaviour unchanged).
+
+## [1.4.1] — 2026-07-14
+
+Version sync with the workspace; inherits libfreemkv 1.4.1.
+
+## [1.4.0] — 2026-07-13
+
+Version sync with the workspace; inherits libfreemkv 1.4.0.
+
 ## [1.3.2] — 2026-07-10
 
 ### Changed

CODE_OF_CONDUCT.md

@@ -36,7 +36,7 @@ This Code of Conduct applies within all community spaces, and also applies when
 
 ## Enforcement
 
-Instances of abusive, harassing, or otherwise unacceptable behavior may be reported to the community leaders responsible for enforcement at owner@example.invalid. All complaints will be reviewed and investigated promptly and fairly.
+Instances of abusive, harassing, or otherwise unacceptable behavior may be reported privately to the project maintainer via GitHub at https://github.com/MattJackson. All complaints will be reviewed and investigated promptly and fairly.
 
 All community leaders are obligated to respect the privacy and security of the reporter of any incident.
 

Cargo.toml

@@ -1,10 +1,10 @@
 [package]
 name = "freemkv-keysources"
-version = "1.3.2"
+version = "1.6.0"
 edition = "2024"
-rust-version = "1.86"
+rust-version = "1.97"
 license = "MIT"
-description = "Pluggable AACS key sources (keydb, online key service) for libfreemkv. Each source looks a disc up and hands libfreemkv its terminal Unit Keys via get_uk; the library does all derivation."
+description = "Pluggable AACS key sources (keydb, online key service) for libfreemkv. Each source looks a disc up and hands libfreemkv its terminal Unit Keys via get_unit_keys; the library does all derivation."
 repository = "https://github.com/freemkv/freemkv-keysources"
 keywords = ["aacs", "blu-ray", "uhd", "decryption", "keydb"]
 categories = ["multimedia"]
@@ -17,7 +17,7 @@ publish = false
 # The crate provides the `KeySource` trait + `Key`/`DiscInputs` types these impls fill.
 # libfreemkv is git-only now; the committed [patch.crates-io] below redirects this
 # bare version req to the libfreemkv git tag (local dev overrides it to a path).
-libfreemkv = "1.3"
+libfreemkv = "1.6"
 # OnlineSource: POST disc inputs + samples to a key service over HTTP.
 ureq = { version = "2", features = ["json"] }
 serde_json = "1"
@@ -34,10 +34,10 @@ tracing = "0.1"
 lto = "thin"
 codegen-units = 1
 
-# libfreemkv is git-only (off crates.io). Redirect the bare `libfreemkv = "1.2"`
+# libfreemkv is git-only (off crates.io). Redirect the bare `libfreemkv = "1.5"`
 # req above to the git tag — committed and CI-visible. The release script
 # rewrites this tag to the new version before regenerating Cargo.lock. Local dev
 # overrides it with a path patch via the gitignored .cargo/config.toml (a
 # config-level [patch.crates-io] wins over this manifest one for the same crate).
 [patch.crates-io]
-libfreemkv = { git = "https://github.com/freemkv/libfreemkv", tag = "v1.3.2" }
+libfreemkv = { git = "https://github.com/freemkv/libfreemkv", tag = "v1.6.0" }

src/keydb.rs

@@ -41,9 +41,11 @@ use libfreemkv::{Error, KeySource};
 use crate::keydb_format::KeyDb;
 
 /// Upper bound on decompressed keydb size. The published keydb is a few MiB;
-/// 64 MiB is a generous ceiling that still caps a decompression bomb (a tiny
-/// zip/gz can otherwise inflate to GiB and OOM the daily refresh thread).
-const MAX_KEYDB_BYTES: u64 = 64 * 1024 * 1024;
+/// 128 MiB is a generous ceiling that still caps a decompression bomb (a tiny
+/// zip/gz can otherwise inflate to GiB and OOM the daily refresh thread). The
+/// public UHD keydb is ~62 MiB and growing, so 64 MiB was getting tight;
+/// 128 MiB leaves years of headroom.
+const MAX_KEYDB_BYTES: u64 = 128 * 1024 * 1024;
 
 /// Result of a KEYDB save/update -- path written, entry count, and byte size.
 #[derive(Debug)]
@@ -328,10 +330,14 @@ fn write_atomic(path: &Path, text: &str) -> Result<(), Error> {
 }
 
 impl KeySource for KeydbSource {
-    /// Resolve this disc's terminal Unit Keys from the keydb. A missing /
+    /// Resolve this disc's base per-CPS-unit Unit Keys from the keydb. A missing /
     /// unreadable keydb is not an error — it simply yields no keys (another
     /// source may have them), the same as the library's own loader.
-    fn get_uk(&self, ctx: &dyn ResolveCtx) -> Result<Vec<UnitKey>, Error> {
+    ///
+    /// The keydb carries no AACS 2.1 forensic index keys today, so it does not
+    /// override `get_fmts_indexes` — the default (empty) opts it out, and an FMTS
+    /// disc's forensic set comes from the online source.
+    fn get_unit_keys(&self, ctx: &dyn ResolveCtx) -> Result<Vec<UnitKey>, Error> {
         match KeyDb::load(&self.path) {
             Ok(db) => Ok(Self::unit_keys_from(&db, ctx)),
             Err(_) => Ok(Vec::new()),
@@ -363,7 +369,7 @@ mod tests {
     use libfreemkv::aacs::types::DeviceKey;
     use std::collections::HashMap;
 
-    // ── A test ResolveCtx, so get_uk's path selection can be exercised without
+    // ── A test ResolveCtx, so get_unit_keys's path selection can be exercised without
     //    a real Disc. Each accessor returns exactly what a case needs. ──────────
     struct MockCtx {
         disc_hash: String,
@@ -748,7 +754,7 @@ mod tests {
     fn get_uk_missing_keydb_is_ok_empty() {
         let src = KeydbSource::new("/nonexistent/path/keydb.cfg");
         let got = src
-            .get_uk(&ctx(HASH, Vec::new(), None))
+            .get_unit_keys(&ctx(HASH, Vec::new(), None))
             .expect("missing keydb is not an error");
         assert!(got.is_empty());
     }

src/keydb_format.rs

@@ -23,9 +23,10 @@ use libfreemkv::aacs::types::{DeviceKey, HostCert};
 pub type NumberedUnitKey = (u32, [u8; 16]);
 
 /// Upper bound on the on-disk keydb.cfg size accepted by [`KeyDb::load`].
-/// The real public UHD keydb is a few MiB; 64 MiB is generous headroom while
-/// still bounding the worst-case allocation from a hostile/corrupt file.
-const MAX_KEYDB_BYTES: u64 = 64 * 1024 * 1024;
+/// The public UHD keydb is ~62 MiB and growing; 128 MiB is generous
+/// headroom while still bounding the worst-case allocation from a hostile or
+/// corrupt file.
+const MAX_KEYDB_BYTES: u64 = 128 * 1024 * 1024;
 
 /// Upper bound on parsed disc entries. The real public keydb carries
 /// ~170k+ entries, so the cap sits well above that while still bounding
@@ -264,22 +265,33 @@ impl KeyDb {
     /// [`KeyDb`] rather than an error — callers needing a non-empty db must
     /// check the parsed contents.
     pub fn load(path: &std::path::Path) -> std::io::Result<Self> {
-        // Stat-and-cap before reading so a hostile/corrupt file can't force an
-        // unbounded allocation. A file strictly over the cap is rejected (a
-        // file exactly at MAX_KEYDB_BYTES is accepted, matching the `>` guard
-        // and libfreemkv's original at-cap-is-allowed semantics).
-        if let Ok(meta) = std::fs::metadata(path) {
-            if meta.len() > MAX_KEYDB_BYTES {
-                return Err(std::io::Error::new(
-                    std::io::ErrorKind::InvalidData,
-                    format!(
-                        "keydb.cfg exceeds {MAX_KEYDB_BYTES} byte cap: {}",
-                        path.display()
-                    ),
-                ));
-            }
+        // Read through a hard `take` cap rather than trusting a stat. A
+        // `metadata` pre-check is only advisory: it is skipped entirely when the
+        // stat fails, and it reports len 0 for a FIFO or character device, so
+        // `--keydb /dev/zero` passed the guard and then read forever (NUL is
+        // valid UTF-8, so it did not even fail the decode — it just grew until
+        // the process was OOM-killed). Reading one byte past the cap accepts an
+        // exactly-at-cap file and rejects anything larger, matching
+        // `read_capped_to_string` on the download path.
+        use std::io::Read;
+        let f = std::fs::File::open(path)?;
+        let mut buf = Vec::new();
+        f.take(MAX_KEYDB_BYTES + 1).read_to_end(&mut buf)?;
+        if buf.len() as u64 > MAX_KEYDB_BYTES {
+            return Err(std::io::Error::new(
+                std::io::ErrorKind::InvalidData,
+                format!(
+                    "keydb.cfg exceeds {MAX_KEYDB_BYTES} byte cap: {}",
+                    path.display()
+                ),
+            ));
         }
-        let data = std::fs::read_to_string(path)?;
+        let data = String::from_utf8(buf).map_err(|_| {
+            std::io::Error::new(
+                std::io::ErrorKind::InvalidData,
+                format!("keydb.cfg is not valid UTF-8: {}", path.display()),
+            )
+        })?;
         Ok(Self::parse(&data))
     }
 
@@ -506,9 +518,12 @@ impl KeyDb {
 
         Some(DeviceKey {
             key: parse_hex16(key_str)?,
-            node: u16::from_str_radix(node_str.trim_start_matches("0x"), 16).ok()?,
-            uv: u32::from_str_radix(uv_str.trim_start_matches("0x"), 16).ok()?,
-            u_mask_shift: u8::from_str_radix(shift_str.trim_start_matches("0x"), 16).ok()?,
+            // Canonical hex parsers (one prefix/case rule for the whole workspace)
+            // — NOT an ad-hoc `from_str_radix(trim_start_matches("0x"))`, whose
+            // case-sensitive strip silently dropped an uppercase-`0X` value.
+            node: libfreemkv::hex::parse_hex_u16(node_str)?,
+            uv: libfreemkv::hex::parse_hex_u32(uv_str)?,
+            u_mask_shift: libfreemkv::hex::parse_hex_u8(shift_str)?,
         })
     }
 
@@ -683,22 +698,19 @@ impl KeyDb {
                         i += 1;
                     }
                 }
-                "U" => {
-                    if i + 1 < parts.len() {
-                        // Unit keys: "1-0xKEY" or "1-0xKEY ; comment"
-                        let uk_str = parts[i + 1].split(';').next().unwrap_or("").trim();
-                        for uk in uk_str.split(' ') {
-                            let uk = uk.trim();
-                            if let Some((num, key)) = uk.split_once('-') {
-                                if let Ok(n) = num.parse::<u32>() {
-                                    if let Some(k) = parse_hex16(key) {
-                                        unit_keys.push((n, k));
-                                    }
-                                }
-                            }
+                "U" if i + 1 < parts.len() => {
+                    // Unit keys: "1-0xKEY" or "1-0xKEY ; comment"
+                    let uk_str = parts[i + 1].split(';').next().unwrap_or("").trim();
+                    for uk in uk_str.split(' ') {
+                        let uk = uk.trim();
+                        if let Some((num, key)) = uk.split_once('-')
+                            && let Ok(n) = num.parse::<u32>()
+                            && let Some(k) = parse_hex16(key)
+                        {
+                            unit_keys.push((n, k));
                         }
-                        i += 1;
                     }
+                    i += 1;
                 }
                 _ => {}
             }
@@ -723,6 +735,43 @@ impl KeyDb {
 mod tests {
     use super::*;
 
+    /// `load` must enforce `MAX_KEYDB_BYTES` through a bounded read, not a stat.
+    ///
+    /// Regression: the cap used to be a `std::fs::metadata` pre-check followed by
+    /// an unbounded `read_to_string`. That is not a cap — it is skipped when the
+    /// stat fails, and a FIFO or character device reports len 0, so the guard
+    /// passed and the read never terminated. NUL bytes are valid UTF-8, so
+    /// `--keydb /dev/zero` did not even fail the decode; it allocated until the
+    /// process died. Asserts both edges of the boundary so a future cap change
+    /// cannot quietly re-introduce an off-by-one.
+    #[test]
+    fn load_enforces_the_size_cap_at_both_edges() {
+        let dir = std::env::temp_dir()
+            .join("fmkv-keydb-cap")
+            .join(format!("{}", std::process::id()));
+        std::fs::create_dir_all(&dir).unwrap();
+
+        // Exactly at the cap is accepted. Use a comment line so `parse` is happy
+        // and the content is valid UTF-8 of a known length.
+        let at = dir.join("at_cap.cfg");
+        let body = vec![b'#'; MAX_KEYDB_BYTES as usize];
+        std::fs::write(&at, &body).unwrap();
+        assert!(
+            KeyDb::load(&at).is_ok(),
+            "a file exactly at MAX_KEYDB_BYTES must load"
+        );
+
+        // One byte over is rejected as InvalidData, not truncated and not OOM.
+        let over = dir.join("over_cap.cfg");
+        let mut body = vec![b'#'; MAX_KEYDB_BYTES as usize];
+        body.push(b'#');
+        std::fs::write(&over, &body).unwrap();
+        let err = KeyDb::load(&over).expect_err("over-cap file must be rejected");
+        assert_eq!(err.kind(), std::io::ErrorKind::InvalidData);
+
+        std::fs::remove_dir_all(&dir).ok();
+    }
+
     /// `to_keydb_cfg` is the exact inverse of `parse`: parse a known line set,
     /// serialize it, re-parse, and every field survives — device key, processing
     /// key, host cert (priv key + cert + revocation), and the per-disc M/I(vid)/V/U
@@ -730,11 +779,7 @@ mod tests {
     /// internal key forms (e.g. the `0x`-prefixed disc-hash) match by construction.
     #[test]
     fn to_keydb_cfg_round_trips_through_parse() {
-        let h = |b: u8, n: usize| {
-            std::iter::repeat(format!("{b:02x}"))
-                .take(n)
-                .collect::<String>()
-        };
+        let h = |b: u8, n: usize| format!("{b:02x}").repeat(n);
         let cert = h(0x99, 92); // AACS 1.0 host cert is 92 bytes
         let src = format!(
             "| HC | HOST_PRIV_KEY 0x{priv20} | HOST_CERT 0x{cert} ; Revoked in MKBv72\n\
@@ -1219,6 +1264,20 @@ mod tests {
         assert!(db.processing_keys.is_empty());
     }
 
+    #[test]
+    fn parse_device_key_accepts_uppercase_0x_prefix() {
+        // Regression: node/uv/shift parsed via a case-sensitive
+        // `trim_start_matches("0x")`, so an uppercase `0X` prefix was not
+        // stripped, `from_str_radix` failed, and the WHOLE device key was
+        // silently dropped. All four fields must parse regardless of prefix case.
+        let line = "| DK | DEVICE_KEY 0x000102030405060708090A0B0C0D0E0F \
+                    | DEVICE_NODE 0X0001 | KEY_UV 0X00000002 | KEY_U_MASK_SHIFT 0X03";
+        let dk = KeyDb::parse_device_key(line).expect("uppercase 0X prefix must parse");
+        assert_eq!(dk.node, 1);
+        assert_eq!(dk.uv, 2);
+        assert_eq!(dk.u_mask_shift, 3);
+    }
+
     #[test]
     fn parse_host_cert_v2_rejects_wrong_priv_len_and_short_cert() {
         // v2 priv must be exactly 32 bytes; cert must be >= 132.
@@ -1412,7 +1471,7 @@ mod tests {
     //
     // These exercise the parser (KeyDb::load) end-to-end against a real
     // keydb.cfg and feed its material into libfreemkv's AACS crypto
-    // (derive_vuk / decrypt_unit_try_keys). They live here now that the
+    // (derive_vuk, then decrypt_unit + is_clean_ts). They live here now that the
     // parser lives here. All are KEYDB_PATH-env-gated and no-op in CI when
     // the env is unset; they must still COMPILE.
     // ════════════════════════════════════════════════════════════════════
@@ -1466,7 +1525,7 @@ mod tests {
         let original = std::fs::read(&unit_path).unwrap();
         assert_eq!(original.len(), libfreemkv::aacs::content::ALIGNED_UNIT_LEN);
         assert!(
-            libfreemkv::aacs::content::ts_sync_destroyed(&original),
+            !libfreemkv::aacs::content::is_clean(&original, libfreemkv::disc::ContentFormat::BdTs),
             "Unit should be encrypted"
         );
 
@@ -1485,20 +1544,20 @@ mod tests {
 
         eprintln!("Found {} entries with unit keys", candidate_entries.len());
 
-        // Try each entry's unit keys
+        // Try each entry's unit keys: apply the key, then ask whether it opened
+        // the unit (the segregated primitives — decrypt, then structural check).
         for entry in &candidate_entries {
-            let keys: Vec<[u8; 16]> = entry.unit_keys.iter().map(|(_, k)| *k).collect();
-            let mut unit = original.clone();
-
-            if let Some(res) = libfreemkv::aacs::content::decrypt_unit_try_keys(&mut unit, &keys) {
-                eprintln!(
-                    "SUCCESS: Decrypted with entry {} ({res:?})",
-                    entry.disc_hash
-                );
-                // Count TS sync bytes
-                let ts = (0..32).filter(|&i| unit[4 + i * 192] == 0x47).count();
-                eprintln!("  TS sync bytes: {}/32", ts);
-                return;
+            for (_, key) in &entry.unit_keys {
+                let mut unit = original.clone();
+                libfreemkv::aacs::content::decrypt_unit(&mut unit, key);
+                if libfreemkv::aacs::content::is_clean(&unit, libfreemkv::disc::ContentFormat::BdTs)
+                {
+                    eprintln!("SUCCESS: Decrypted with entry {}", entry.disc_hash);
+                    // Count TS sync bytes
+                    let ts = (0..32).filter(|&i| unit[4 + i * 192] == 0x47).count();
+                    eprintln!("  TS sync bytes: {}/32", ts);
+                    return;
+                }
             }
         }
 
@@ -1527,7 +1586,7 @@ mod tests {
         let entry = entry.unwrap();
         let vuk = entry.vuk.unwrap();
         let vid = entry.vid.unwrap();
-        let hash_hex = format!("0x{}", entry.disc_hash.trim_start_matches("0x"));
+        let hash_hex = format!("0x{}", libfreemkv::hex::strip_hex_prefix(&entry.disc_hash));
 
         // We need the actual Unit_Key_RO.inf from the disc to compute disc hash.
         // Since we don't have it, we can at least test that the KEYDB lookup

src/lib.rs

@@ -12,7 +12,7 @@
 //! in — then resolve and hand the resulting key to `Disc::decrypt_with`.
 //!
 //! Each source resolves a disc's terminal **Unit Keys** in one shot via
-//! [`KeySource::get_uk`], driving libfreemkv's boil-down crypto primitives for
+//! [`KeySource::get_unit_keys`], driving libfreemkv's boil-down crypto primitives for
 //! whatever level of material it holds. Compose several with [`MultiSource`] in
 //! the caller's chosen order. Reading the encrypted content-sample units a key
 //! server validates on, and applying the resolved keys against a disc, is
@@ -30,7 +30,7 @@ mod paths;
 
 pub use keydb::{KeydbSource, UpdateResult};
 pub use keydb_format::{DiscEntry, KeyDb};
-pub use online::{OnlineSource, validate_keyserver_url};
+pub use online::{MIN_SAMPLE_UNITS, OnlineSource, validate_keyserver_url};
 pub use paths::{default_keydb_path, existing_keydb_path, keydb_search_paths};
 
 // Re-exported for downstream convenience so apps need only depend on this crate
@@ -51,9 +51,11 @@ pub(crate) fn uks_from_vuk(vuk: &[u8; 16], enc_title_keys: &[[u8; 16]]) -> Vec<U
         .collect()
 }
 
-/// An ordered composition of key sources, driven as one. [`MultiSource::get_uk`]
-/// tries each inner source in order and returns the first non-empty Unit Key
-/// set. **The caller supplies the list AND the order** — local-first `[Keydb,
+/// An ordered composition of key sources, driven as one.
+/// [`MultiSource::get_unit_keys`] tries each inner source in order and returns
+/// the first non-empty Unit Key set (and [`MultiSource::get_fmts_indexes`] does
+/// the same for the forensic set). **The caller supplies the list AND the
+/// order** — local-first `[Keydb,
 /// Online]`, online-first `[Online, Keydb]`, etc. —
 /// so the "which sources, in what order" policy lives entirely with the
 /// application, not the library. `MultiSource` is itself a [`KeySource`], so it
@@ -70,16 +72,31 @@ impl MultiSource {
 }
 
 impl KeySource for MultiSource {
-    /// Try each inner source in order; the FIRST to return a non-empty Unit Key
-    /// set wins. An inner source that returns empty OR errors is treated as "no
-    /// key here" and the next is tried (a single source failure never blocks the
-    /// chain). All sources exhausted → empty.
-    fn get_uk(&self, ctx: &dyn ResolveCtx) -> Result<Vec<UnitKey>, libfreemkv::Error> {
+    /// Try each inner source in order; the FIRST to return a non-empty base Unit
+    /// Key set wins. An inner source that returns empty OR errors is treated as
+    /// "no key here" and the next is tried (a single source failure never blocks
+    /// the chain). All sources exhausted → empty.
+    fn get_unit_keys(&self, ctx: &dyn ResolveCtx) -> Result<Vec<UnitKey>, libfreemkv::Error> {
         for s in &self.sources {
-            if let Ok(uks) = s.get_uk(ctx) {
-                if !uks.is_empty() {
-                    return Ok(uks);
-                }
+            if let Ok(uks) = s.get_unit_keys(ctx)
+                && !uks.is_empty()
+            {
+                return Ok(uks);
+            }
+        }
+        Ok(Vec::new())
+    }
+
+    /// Forensic-index counterpart: try each inner source's `get_fmts_indexes` in
+    /// the same order and return the first non-empty set. A source with no
+    /// forensic material (the keydb, via the trait default) contributes empty and
+    /// is skipped; on today's discs the online source answers.
+    fn get_fmts_indexes(&self, ctx: &dyn ResolveCtx) -> Result<Vec<UnitKey>, libfreemkv::Error> {
+        for s in &self.sources {
+            if let Ok(uks) = s.get_fmts_indexes(ctx)
+                && !uks.is_empty()
+            {
+                return Ok(uks);
             }
         }
         Ok(Vec::new())

src/online.rs

@@ -7,7 +7,7 @@ use std::time::Duration;
 use crate::uks_from_vuk;
 use base64::Engine;
 use libfreemkv::aacs::types::UnitKey;
-use libfreemkv::keysource::ResolveCtx;
+use libfreemkv::keysource::{DecodeSampleSet, ResolveCtx};
 use libfreemkv::{Error, KeySource};
 
 // Upper bound on the MKB forwarded to the key service — kept in lockstep with
@@ -16,6 +16,19 @@ use libfreemkv::{Error, KeySource};
 // record stream is normally a few MiB; this is headroom, not an expected size).
 const MAX_MKB_BYTES: usize = 64 * 1024 * 1024;
 const TIMEOUT_SECS: u64 = 180;
+/// Minimum encrypted-content samples the online source will send in one key
+/// request — re-exported from the base crate ([`libfreemkv::keysource::MIN_SAMPLE_UNITS`])
+/// so this crate and libfreemkv's own FMTS forensic query share ONE value.
+///
+/// The service identifies the key by which of the submitted units it decrypts,
+/// so too few samples — especially on FMTS, where a segment interleaves several
+/// variants at the unit level — can return a key that matches an incidental unit
+/// rather than the one asked about (a false positive). A request carrying fewer
+/// is refused (empty result → the resolver moves to the next source) rather than
+/// sent and trusted. Kept public so callers that GATHER the samples (the CLI,
+/// autorip) sample at least this many — sampling fewer guarantees the request is
+/// skipped and the online source never consulted.
+pub use libfreemkv::keysource::MIN_SAMPLE_UNITS;
 /// Hard cap on the key-service response body. A real unit-key reply is a few
 /// hundred bytes; bound the read so a malicious/compromised server can't drive
 /// the client to OOM with an unbounded body.
@@ -74,34 +87,59 @@ fn is_blocked_ip(ip: &IpAddr) -> bool {
     }
 }
 
+/// Why [`resolve_and_guard`] rejected a URL. The two halves demand OPPOSITE
+/// operator actions, so they must not be collapsed: a `Config` rejection is a
+/// standing misconfiguration that will never fix itself, while `Unreachable` is
+/// the key service being down right now — exactly the condition this module's
+/// callers must not report as "this disc has no key".
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+enum GuardFail {
+    /// Malformed URL, bad scheme, or a host that is (or resolves to) a
+    /// non-public address. Operator configuration; retrying changes nothing.
+    Config,
+    /// The host did not resolve — DNS failure or DNS timeout. The service is
+    /// unreachable; nothing is known about this disc's key. Transient.
+    Unreachable,
+}
+
 /// Resolve `url`'s host and validate every resulting address against the SSRF
 /// guard. Returns the pinned socket addresses (for use with a custom ureq
-/// resolver) on success, or an error message on rejection.
-fn resolve_and_guard(url: &str) -> Result<Vec<SocketAddr>, String> {
+/// resolver) on success, or the rejection reason plus an explanatory message.
+///
+/// SECURITY: the message names the resolved address on an SSRF rejection and is
+/// for the CONFIG-time caller only — never log it (see the call site in
+/// [`OnlineSource::query`]).
+fn resolve_and_guard(url: &str) -> Result<Vec<SocketAddr>, (GuardFail, String)> {
     let rest = if let Some(r) = url.strip_prefix("https://") {
         (r, 443u16)
     } else if let Some(r) = url.strip_prefix("http://") {
         (r, 80u16)
     } else {
-        return Err("URL must start with http:// or https://".into());
+        return Err((
+            GuardFail::Config,
+            "URL must start with http:// or https://".into(),
+        ));
     };
     let (authority, default_port) = rest;
     let authority = authority.split(['/', '?', '#']).next().unwrap_or(authority);
     let authority = authority.rsplit('@').next().unwrap_or(authority);
     if authority.is_empty() {
-        return Err("URL has no host".into());
+        return Err((GuardFail::Config, "URL has no host".into()));
     }
     let (host, port): (String, u16) = if let Some(stripped) = authority.strip_prefix('[') {
         match stripped.split_once(']') {
             Some((h, after)) => {
                 let p = after
                     .strip_prefix(':')
-                    .map(|s| s.parse::<u16>().map_err(|_| "invalid port".to_string()))
+                    .map(|s| {
+                        s.parse::<u16>()
+                            .map_err(|_| (GuardFail::Config, "invalid port".to_string()))
+                    })
                     .transpose()?
                     .unwrap_or(default_port);
                 (h.to_string(), p)
             }
-            None => return Err("malformed IPv6 host".into()),
+            None => return Err((GuardFail::Config, "malformed IPv6 host".into())),
         }
     } else if let Some((h, p)) = authority.rsplit_once(':') {
         match p.parse::<u16>() {
@@ -112,7 +150,7 @@ fn resolve_and_guard(url: &str) -> Result<Vec<SocketAddr>, String> {
         (authority.to_string(), default_port)
     };
     if host.is_empty() {
-        return Err("URL has no host".into());
+        return Err((GuardFail::Config, "URL has no host".into()));
     }
     // `to_socket_addrs` is a BLOCKING DNS lookup that can hang for the OS
     // resolver timeout (tens of seconds) and freeze the rip thread that called
@@ -133,18 +171,29 @@ fn resolve_and_guard(url: &str) -> Result<Vec<SocketAddr>, String> {
         });
         match rx.recv_timeout(DNS_TIMEOUT) {
             Ok(Ok(addrs)) => addrs,
-            Ok(Err(e)) => return Err(format!("could not resolve host: {e}")),
-            Err(_) => return Err("DNS resolution timed out".into()),
+            Ok(Err(e)) => {
+                return Err((
+                    GuardFail::Unreachable,
+                    format!("could not resolve host: {e}"),
+                ));
+            }
+            Err(_) => return Err((GuardFail::Unreachable, "DNS resolution timed out".into())),
         }
     };
     if addrs.is_empty() {
-        return Err("host did not resolve to any address".into());
+        return Err((
+            GuardFail::Unreachable,
+            "host did not resolve to any address".into(),
+        ));
     }
     for a in &addrs {
         if is_blocked_ip(&a.ip()) {
-            return Err(format!(
-                "refusing to connect to non-public address {} (SSRF guard)",
-                a.ip()
+            return Err((
+                GuardFail::Config,
+                format!(
+                    "refusing to connect to non-public address {} (SSRF guard)",
+                    a.ip()
+                ),
             ));
         }
     }
@@ -165,7 +214,7 @@ fn resolve_and_guard(url: &str) -> Result<Vec<SocketAddr>, String> {
 /// SAME bounded-resolve, so their verdicts never diverge — the reason this lives
 /// here, in the key-source crate, rather than being re-rolled per application.
 pub fn validate_keyserver_url(url: &str) -> Result<(), String> {
-    resolve_and_guard(url).map(|_| ())
+    resolve_and_guard(url).map(|_| ()).map_err(|(_, msg)| msg)
 }
 
 /// Build a ureq agent that follows zero redirects (so a public URL can't
@@ -193,18 +242,54 @@ impl OnlineSource {
         }
     }
 
-    /// The server-resolved Unit Keys for this disc, or an empty `Vec`. Runs
-    /// exactly one network round-trip. The service returns either a terminal
-    /// `UK` (used directly) or a `VUK` (derived to Unit Keys locally via the
-    /// disc's encrypted title keys from `ctx`). Any failure — no service,
-    /// over-cap MKB, network/parse error, or no key for this disc — yields an
-    /// empty `Vec` (the resolver tries the next source). `&self`: one-shot is
-    /// the resolver's contract (each source's `get_uk` is called once), so no
-    /// per-call latch is needed.
-    fn query(&self, ctx: &dyn ResolveCtx) -> Vec<UnitKey> {
+    /// The server-resolved Unit Keys for this disc. Runs exactly one network
+    /// round-trip. The service returns either a terminal `UK` (used directly) or
+    /// a `VUK` (derived to Unit Keys locally via the disc's encrypted title keys
+    /// from `ctx`).
+    ///
+    /// The return type draws THE distinction this source exists to draw:
+    ///
+    /// * `Ok(non-empty)` — the service answered with a key.
+    /// * `Ok(empty)` — the service ANSWERED and holds no key for this disc, or
+    ///   this source had nothing to ask with (no service configured, a
+    ///   misconfigured URL, an over-cap MKB, too few samples). A genuine miss;
+    ///   the resolver moves to the next source and `E7022` is the right verdict.
+    /// * `Err(..)` — the service could not answer: unreachable, timed out, DNS
+    ///   failed, returned 5xx, rejected the token (401/403), rate-limited (429),
+    ///   or replied with something unreadable. NOTHING is known about whether a
+    ///   key exists. Collapsing this into `Ok(empty)` is the bug this signature
+    ///   fixes: a seven-hour run of HTTP 502s was reported to operators as
+    ///   `E7022 No key source has a decryption key for this disc`, and they went
+    ///   hunting for a VUK when the correct action was to wait.
+    ///
+    /// `&self`: one-shot is the resolver's contract (each source's
+    /// `get_unit_keys` is called once), so no per-call latch is needed.
+    fn query(&self, ctx: &dyn ResolveCtx) -> Result<Vec<UnitKey>, Error> {
         // No configured service: nothing to resolve.
         if self.base_url.is_empty() {
-            return Vec::new();
+            return Ok(Vec::new());
+        }
+        // Refuse to transmit over plaintext. The request body always carries
+        // base64 AACS key material (inf/mkb/units/vid) and, when configured, a
+        // bearer token in a header — so an `http://` POST hands both to any
+        // on-path observer, and the token is replayable.
+        //
+        // There is no legitimate plaintext deployment to preserve here: the
+        // address guard below rejects loopback, RFC1918, ULA and link-local, so
+        // an `http://` URL can only ever reach the PUBLIC internet — the single
+        // worst case for cleartext. A self-hosted keyserver on a LAN is already
+        // impossible by that guard, whatever its scheme.
+        //
+        // Falls through to the next key source (a local keydb) rather than
+        // failing the rip, and says why — misconfiguration should be visible,
+        // not silently indistinguishable from "this disc has no key".
+        if !self.base_url.starts_with("https://") {
+            tracing::warn!(
+                target: "freemkv::keysource",
+                "key-service URL is not https:// — refusing to send key material \
+                 and credentials in cleartext; skipping the online source"
+            );
+            return Ok(Vec::new());
         }
         let mkb = ctx.mkb().unwrap_or(&[]);
         // An over-cap MKB cannot be forwarded — bound the body. Log it: a silent
@@ -217,8 +302,25 @@ impl OnlineSource {
                 cap = MAX_MKB_BYTES,
                 "MKB exceeds the key-service forward cap; skipping the online source for this disc (no key from online)"
             );
-            return Vec::new();
+            return Ok(Vec::new());
         }
+        // Gather encrypted-content samples and prove the minimum by TYPE: a
+        // `DecodeSampleSet` only exists with >= MIN_SAMPLE_UNITS units, so from here
+        // on the request cannot be built under-sized. The service resolves a key by
+        // which submitted unit it decrypts, so a request carrying too few can return
+        // a key matching an incidental unit (a false positive, seen on FMTS variant
+        // units) — too few → skip this source and fall through to the next.
+        let gathered = ctx.samples(64).unwrap_or_default();
+        let n = gathered.len();
+        let Some(samples) = DecodeSampleSet::new(gathered) else {
+            tracing::info!(
+                target: "freemkv::keysource",
+                samples = n,
+                min = MIN_SAMPLE_UNITS,
+                "too few content samples for a reliable online key request; skipping the online source"
+            );
+            return Ok(Vec::new());
+        };
         let b64 = base64::engine::general_purpose::STANDARD;
         let mut body = serde_json::json!({
             // Raw Unit_Key_RO.inf, verbatim — the server does its own parse /
@@ -229,24 +331,21 @@ impl OnlineSource {
         if let Some(vid) = ctx.vid() {
             body["vid_b64"] = serde_json::Value::String(b64.encode(vid.0));
         }
-        // Up to a generous cap of encrypted content samples for server-side
-        // ciphertext validation.
-        if let Ok(samples) = ctx.samples(64) {
-            if !samples.is_empty() {
-                body["units_b64"] = serde_json::Value::Array(
-                    samples
-                        .iter()
-                        .map(|u| serde_json::Value::String(b64.encode(u)))
-                        .collect(),
-                );
-            }
-        }
+        // Encrypted-content samples for server-side ciphertext validation (already
+        // gathered + minimum-checked above).
+        body["units_b64"] = serde_json::Value::Array(
+            samples
+                .units()
+                .iter()
+                .map(|u| serde_json::Value::String(b64.encode(u)))
+                .collect(),
+        );
         // The disc's own title (UDF/ISO volume id), plain text. The key service
         // catalogs it by disc_hash (its disc-titles.json) — independent of keydb.
-        if let Some(label) = ctx.title().map(str::trim) {
-            if !label.is_empty() {
-                body["title"] = serde_json::Value::String(label.to_string());
-            }
+        if let Some(label) = ctx.title().map(str::trim)
+            && !label.is_empty()
+        {
+            body["title"] = serde_json::Value::String(label.to_string());
         }
         // Resolve + SSRF-guard the host just before the POST; pin the
         // validated addresses into a redirect-disabled agent so a DNS
@@ -254,7 +353,33 @@ impl OnlineSource {
         // request (and the bearer token) to an internal/metadata host.
         let pinned = match resolve_and_guard(&self.base_url) {
             Ok(addrs) => addrs,
-            Err(_) => return Vec::new(),
+            // A host that did not RESOLVE is the service being unreachable, not a
+            // bad URL — DNS failure and DNS timeout are exactly what a key-service
+            // outage looks like from here, and reporting them as a genuine miss is
+            // the same conflation as reporting a 502 that way.
+            Err((GuardFail::Unreachable, _)) => {
+                tracing::warn!(
+                    target: "freemkv::keysource",
+                    phase = "keyserver_post",
+                    "key-service host did not resolve (DNS failure or timeout); \
+                     the service is unreachable, not out of keys"
+                );
+                return Err(Error::KeyServiceUnavailable);
+            }
+            Err((GuardFail::Config, _)) => {
+                // Log THAT the URL was rejected, never WHY: the guard's message
+                // names the resolved address, and an internal address must not
+                // reach a log an operator may paste into a bug report. The
+                // static label is enough to separate "misconfigured/blocked
+                // key-service URL" from "this disc has no key", which is the
+                // only distinction the operator needs here.
+                tracing::warn!(
+                    target: "freemkv::keysource",
+                    phase = "keyserver_post",
+                    "key-service URL failed the address guard; skipping the online source"
+                );
+                return Ok(Vec::new());
+            }
         };
         let agent = hardened_agent(pinned);
         let mut req = agent.post(&self.base_url);
@@ -269,59 +394,226 @@ impl OnlineSource {
         // material.
         tracing::info!(target: "freemkv::keysource", phase = "keyserver_post", "begin");
         let post_t0 = std::time::Instant::now();
-        let resp = match req.send_json(body) {
-            Ok(r) => r,
-            Err(_) => {
-                tracing::warn!(
-                    target: "freemkv::keysource",
-                    phase = "keyserver_post",
-                    elapsed_ms = post_t0.elapsed().as_millis() as u64,
-                    "keyserver request failed (timeout, network, or HTTP error)"
-                );
-                return Vec::new();
-            }
-        };
-        tracing::info!(
-            target: "freemkv::keysource",
-            phase = "keyserver_post",
-            elapsed_ms = post_t0.elapsed().as_millis() as u64,
-            "end"
-        );
-        // Bounded read: cap the body so a hostile server can't OOM the client.
-        // Reading MAX_RESPONSE_BYTES+1 lets us detect (and reject) an over-cap body.
-        let mut buf = Vec::new();
-        if resp
-            .into_reader()
-            .take(MAX_RESPONSE_BYTES as u64 + 1)
-            .read_to_end(&mut buf)
-            .is_err()
-            || buf.len() > MAX_RESPONSE_BYTES
-        {
-            return Vec::new();
-        }
-        let json: serde_json::Value = match serde_json::from_slice(&buf) {
-            Ok(j) => j,
-            Err(_) => return Vec::new(),
-        };
-        // A terminal UK is used directly (CPS unit 0 → committed cps 1, matching
-        // the old `Key::Unit(vec![(1, uk)])`).
-        if let Some(uk) = json.get("UK").and_then(|u| u.as_str()).and_then(parse_uk) {
-            return vec![UnitKey::new(0, uk)];
-        }
-        // A VUK is derived to the terminal keys locally, via the disc's
-        // encrypted title keys from the context — the library owns the crypto.
-        if let Some(vuk) = json.get("VUK").and_then(|u| u.as_str()).and_then(parse_uk) {
-            if let Ok(enc) = ctx.enc_title_keys() {
-                return uks_from_vuk(&vuk, enc);
-            }
-        }
-        Vec::new()
+        let sent = req.send_json(body);
+        interpret_reply(sent, ctx, post_t0.elapsed().as_millis() as u64)
     }
 }
 
+/// Map a key-service HTTP status the client never asked for into the operator
+/// action it implies. THE table this fix exists for — each arm is a different
+/// thing for a person to do, and none of them is "your disc has no key":
+///
+/// * 401 / 403 → the token is wrong or expired. Fix the credentials.
+/// * 429 → rate limited. Back off and retry more slowly.
+/// * 5xx → the service is down. Wait; this is the seven-hour-502 case.
+/// * anything else non-2xx → the service is misbehaving in a way this client
+///   cannot interpret. Treated as unavailable, deliberately: the genuine miss is
+///   a **200 with no key in the body**, so a non-2xx status is never evidence
+///   about this disc, and guessing "no key" from one is the original bug.
+fn classify_http_status(code: u16) -> Error {
+    match code {
+        401 | 403 => Error::KeyServiceUnauthorized,
+        429 => Error::KeyServiceRateLimited,
+        _ => Error::KeyServiceUnavailable,
+    }
+}
+
+/// Turn the raw outcome of the key-service POST into this source's answer.
+///
+/// Split out of [`OnlineSource::query`] so the reply → verdict mapping is
+/// testable WITHOUT a network: the SSRF guard in `resolve_and_guard` blocks
+/// loopback by design, so a stub HTTP server on 127.0.0.1 can never be reached
+/// through `query`, and this seam is the only honest way to drive "the service
+/// returned 502" and "the service returned 200 with no entry" through the same
+/// code the rip uses.
+///
+/// `elapsed_ms` is the round-trip time, for the timing logs only.
+///
+/// SECURITY: logs status codes, byte counts and static labels only. The request
+/// body carries base64 AACS key material and the reply carries keys — neither is
+/// ever logged, and nor is a serde parse error (it quotes the offending input).
+fn interpret_reply(
+    sent: Result<ureq::Response, ureq::Error>,
+    ctx: &dyn ResolveCtx,
+    elapsed_ms: u64,
+) -> Result<Vec<UnitKey>, Error> {
+    let resp = match sent {
+        Ok(r) => r,
+        Err(e) => {
+            // Record the HTTP status when the service actually answered:
+            // 401/403 (bad or expired token), 429 (rate limited) and
+            // 5xx (service down) are completely different operator actions,
+            // and collapsing them into one line is why a 502 was read as
+            // "this disc has no key". The status is the service's own
+            // response code — it carries no key material and no address.
+            // A transport error has no status; report it as such rather
+            // than inventing one.
+            //
+            // Each arm now RETURNS the classified error instead of an empty
+            // vec, so the distinction survives past this function.
+            return Err(match e {
+                ureq::Error::Status(code, _) => {
+                    let err = classify_http_status(code);
+                    tracing::warn!(
+                        target: "freemkv::keysource",
+                        phase = "keyserver_post",
+                        http_status = code,
+                        error_code = err.code(),
+                        elapsed_ms,
+                        "key service returned an HTTP error; no ANSWER from online (not a missing key)"
+                    );
+                    err
+                }
+                ureq::Error::Transport(_) => {
+                    tracing::warn!(
+                        target: "freemkv::keysource",
+                        phase = "keyserver_post",
+                        elapsed_ms,
+                        "key service unreachable (connect/timeout/TLS); no ANSWER from online (not a missing key)"
+                    );
+                    Error::KeyServiceUnavailable
+                }
+            });
+        }
+    };
+    tracing::info!(
+        target: "freemkv::keysource",
+        phase = "keyserver_post",
+        elapsed_ms,
+        "end"
+    );
+    // Bounded read: cap the body so a hostile server can't OOM the client.
+    // Reading MAX_RESPONSE_BYTES+1 lets us detect (and reject) an over-cap body.
+    let mut buf = Vec::new();
+    if resp
+        .into_reader()
+        .take(MAX_RESPONSE_BYTES as u64 + 1)
+        .read_to_end(&mut buf)
+        .is_err()
+        || buf.len() > MAX_RESPONSE_BYTES
+    {
+        // Length only — never the body, which carries base64 key material.
+        // A truncated / over-cap body is the service failing mid-answer: the
+        // question went unanswered, so this is a source failure, not a miss.
+        tracing::warn!(
+            target: "freemkv::keysource",
+            phase = "keyserver_post",
+            cap = MAX_RESPONSE_BYTES,
+            "key-service reply was unreadable or over the size cap; no ANSWER from online"
+        );
+        return Err(Error::KeyServiceUnavailable);
+    }
+    let json: serde_json::Value = match serde_json::from_slice(&buf) {
+        Ok(j) => j,
+        Err(_) => {
+            // Never log the parse error or the payload: a serde message
+            // quotes the offending input, which here is key material.
+            // Unparseable is not "no key" — it is the service answering in a
+            // language this client does not speak. Transient / a service bug.
+            tracing::warn!(
+                target: "freemkv::keysource",
+                phase = "keyserver_post",
+                "key-service reply was not valid JSON; no ANSWER from online"
+            );
+            return Err(Error::KeyServiceUnavailable);
+        }
+    };
+    // `UK` is an ARRAY of hex keys (the service always returns an array now,
+    // even of one). A single element is the base Unit Key. A full set (one per
+    // forensic index, ordered index 1..N) is returned for a forensic sample.
+    // Preserve array order and tag each key with its array position, so the
+    // caller can map position → index (element i = index i+1). A bare string is
+    // still accepted for backward compatibility.
+    if let Some(uk) = json.get("UK") {
+        let mut out = Vec::new();
+        if let Some(s) = uk.as_str() {
+            if let Some(k) = parse_uk(s) {
+                out.push(UnitKey::new(0, k));
+            }
+        } else if let Some(arr) = uk.as_array() {
+            // A forensic set is only usable COMPLETE: the mux trusts any
+            // non-empty result as the whole set and never assumes 32 (see
+            // `get_fmts_indexes`). Skipping an unparseable element would
+            // hand back a short set that silently omits an index, so a
+            // malformed element rejects the whole reply — that is a service
+            // bug, not a usable answer, and therefore a source FAILURE.
+            let mut bad = false;
+            for (i, v) in arr.iter().enumerate() {
+                match v.as_str().and_then(parse_uk) {
+                    Some(k) => out.push(UnitKey::new(i as u32, k)),
+                    None => {
+                        bad = true;
+                        break;
+                    }
+                }
+            }
+            if bad {
+                tracing::warn!(
+                    target: "freemkv::keysource",
+                    phase = "keyserver_post",
+                    keys = arr.len(),
+                    "key-service returned a malformed key in the UK set; rejecting the whole reply"
+                );
+                return Err(Error::KeyServiceUnavailable);
+            }
+        }
+        if !out.is_empty() {
+            return Ok(out);
+        }
+    }
+    // A VUK is derived to the terminal keys locally, via the disc's
+    // encrypted title keys from the context — the library owns the crypto.
+    if let Some(vuk) = json.get("VUK").and_then(|u| u.as_str()).and_then(parse_uk) {
+        match ctx.enc_title_keys() {
+            Ok(enc) => return Ok(uks_from_vuk(&vuk, enc)),
+            Err(_) => {
+                // The SERVICE answered correctly; the DISC's encrypted title keys
+                // are what could not be read. Not a service failure, so not an
+                // `Err` from this source — the disc-side reason is the library's
+                // to report.
+                tracing::warn!(
+                    target: "freemkv::keysource",
+                    phase = "keyserver_post",
+                    "key-service returned a VUK but the disc's encrypted title keys \
+                     are unreadable; cannot derive unit keys"
+                );
+                return Ok(Vec::new());
+            }
+        }
+    }
+    // The genuine miss — and the ONLY path that returns `Ok(empty)` from a
+    // completed round-trip. Logged distinctly from every failure above so an
+    // operator can tell "the service has no key for this disc" from "the
+    // service did not answer"; collapsing the two is what made a 502 look like
+    // a missing key. This is the one case where `E7022` is the truth.
+    tracing::info!(
+        target: "freemkv::keysource",
+        phase = "keyserver_post",
+        "key service has no key for this disc"
+    );
+    Ok(Vec::new())
+}
+
 impl KeySource for OnlineSource {
-    fn get_uk(&self, ctx: &dyn ResolveCtx) -> Result<Vec<UnitKey>, Error> {
-        Ok(self.query(ctx))
+    /// Base per-CPS-unit Unit Keys: submit the ctx's content samples and take the
+    /// service's reply (a terminal `UK`, or a `VUK` derived locally). One network
+    /// round-trip. An empty `Ok` means the service ANSWERED and holds no key; an
+    /// `Err` means it could not answer (see [`OnlineSource::query`]). Both let the
+    /// resolver try the next source — the difference is what the operator is told
+    /// when no source has one.
+    fn get_unit_keys(&self, ctx: &dyn ResolveCtx) -> Result<Vec<UnitKey>, Error> {
+        self.query(ctx)
+    }
+
+    /// AACS 2.1 forensic index set: the mux injects an index-1 single-phase anchor
+    /// batch as the ctx's samples; the service maps it to the full ordered set of
+    /// forensic index keys, tagged by array position (element `i` → forensic index
+    /// `i + 1`). Same one round-trip as [`get_unit_keys`](Self::get_unit_keys) —
+    /// the difference is purely which samples the mux gathered and how the caller
+    /// reads the reply. The count is whatever the service returns; the mux trusts
+    /// any non-empty result as the complete set and never assumes 32.
+    fn get_fmts_indexes(&self, ctx: &dyn ResolveCtx) -> Result<Vec<UnitKey>, Error> {
+        self.query(ctx)
     }
 
     fn label(&self) -> &'static str {
@@ -488,6 +780,196 @@ mod tests {
         assert!(validate_keyserver_url("https://8.8.8.8/keys").is_ok());
     }
 
+    // ── the reply → verdict mapping (THE defect) ───────────────────────────
+    //
+    // Driven through `interpret_reply`, the seam `query` hands its round-trip
+    // to. A stub HTTP server is NOT usable here: `resolve_and_guard` blocks
+    // loopback by design (SSRF guard), so 127.0.0.1 can never be reached through
+    // `query`, and pointing the test at a public host would make it a network
+    // test. Everything from the response onward is this function.
+
+    /// A `ResolveCtx` that carries nothing — enough for the reply paths that do
+    /// not derive from a VUK.
+    struct BareCtx;
+    impl ResolveCtx for BareCtx {
+        fn disc_hash(&self) -> &str {
+            "0x422EB"
+        }
+        fn title(&self) -> Option<&str> {
+            None
+        }
+        fn vid(&self) -> Option<libfreemkv::aacs::types::Vid> {
+            None
+        }
+        fn mkb(&self) -> Result<&[u8], Error> {
+            Ok(&[])
+        }
+        fn enc_title_keys(&self) -> Result<&[[u8; 16]], Error> {
+            Ok(&[])
+        }
+        fn samples(&self, _n: usize) -> Result<Vec<Vec<u8>>, Error> {
+            Ok(Vec::new())
+        }
+    }
+
+    fn reply(status: u16, body: &str) -> ureq::Response {
+        ureq::Response::new(status, "stub", body).expect("stub response")
+    }
+
+    /// THE regression. The key service returned HTTP 502 for ~seven hours and
+    /// the CLI told operators the disc had no key, so they went hunting for a
+    /// VUK that was never missing. A 5xx must be a source FAILURE, and it must
+    /// be distinguishable from the service answering 200 with no entry.
+    #[test]
+    fn http_5xx_is_a_source_failure_not_a_missing_key() {
+        for status in [500u16, 502, 503, 504] {
+            let out = interpret_reply(
+                Err(ureq::Error::Status(status, reply(status, ""))),
+                &BareCtx,
+                7,
+            );
+            assert_eq!(
+                out.expect_err("a 5xx must not look like an answer").code(),
+                libfreemkv::error::E_KEY_SERVICE_UNAVAILABLE,
+                "HTTP {status} must report the service as unavailable"
+            );
+        }
+
+        // The contrast case, through the SAME function: the service answered,
+        // and genuinely holds nothing for this disc.
+        let miss = interpret_reply(Ok(reply(200, "{}")), &BareCtx, 7)
+            .expect("a 200 with no key is an ANSWER, not a failure");
+        assert!(miss.is_empty(), "no key in the body → no keys out");
+
+        // And the two must not be the same outcome — the whole point.
+        let down = interpret_reply(Err(ureq::Error::Status(502, reply(502, ""))), &BareCtx, 7);
+        assert!(
+            down.is_err(),
+            "502 and 200-with-no-entry must not collapse to the same result"
+        );
+    }
+
+    /// Each status the service can return maps to a DIFFERENT operator action:
+    /// fix the token (401/403), back off (429), wait (5xx). A non-2xx status is
+    /// never evidence about this disc, so anything else is "unavailable" too —
+    /// guessing "no key" from a status code is the original bug.
+    #[test]
+    fn http_status_maps_to_the_operator_action() {
+        let cases: &[(u16, u16)] = &[
+            (401, libfreemkv::error::E_KEY_SERVICE_UNAUTHORIZED),
+            (403, libfreemkv::error::E_KEY_SERVICE_UNAUTHORIZED),
+            (429, libfreemkv::error::E_KEY_SERVICE_RATE_LIMITED),
+            (500, libfreemkv::error::E_KEY_SERVICE_UNAVAILABLE),
+            (502, libfreemkv::error::E_KEY_SERVICE_UNAVAILABLE),
+            (400, libfreemkv::error::E_KEY_SERVICE_UNAVAILABLE),
+            (404, libfreemkv::error::E_KEY_SERVICE_UNAVAILABLE),
+        ];
+        for (status, want) in cases {
+            assert_eq!(
+                classify_http_status(*status).code(),
+                *want,
+                "HTTP {status} classified wrongly"
+            );
+            assert_ne!(
+                classify_http_status(*status).code(),
+                libfreemkv::error::E_NO_DISC_KEY,
+                "no HTTP status may ever mean \"this disc has no key\""
+            );
+        }
+    }
+
+    /// A transport failure — nothing answered at all — is the same verdict as a
+    /// 5xx and equally not a missing key. Uses a refused connection to
+    /// 127.0.0.1:1 to obtain a REAL `ureq::Error::Transport` (which has no public
+    /// constructor); this touches no network and never reaches `query`, so the
+    /// SSRF guard is not involved.
+    #[test]
+    fn transport_failure_is_a_source_failure() {
+        let sent = ureq::AgentBuilder::new()
+            .timeout_connect(Duration::from_secs(2))
+            .build()
+            .post("http://127.0.0.1:1/")
+            .send_string("{}");
+        assert!(
+            matches!(sent, Err(ureq::Error::Transport(_))),
+            "a refused connection must surface as a ureq transport error"
+        );
+        assert_eq!(
+            interpret_reply(sent, &BareCtx, 3)
+                .expect_err("an unreachable service must not look like an answer")
+                .code(),
+            libfreemkv::error::E_KEY_SERVICE_UNAVAILABLE,
+        );
+    }
+
+    /// A reply the client cannot read is the service failing mid-answer, not an
+    /// answer of "no key".
+    #[test]
+    fn unparseable_reply_is_a_source_failure() {
+        assert_eq!(
+            interpret_reply(Ok(reply(200, "<html>gateway error</html>")), &BareCtx, 1)
+                .expect_err("non-JSON is not an answer")
+                .code(),
+            libfreemkv::error::E_KEY_SERVICE_UNAVAILABLE,
+        );
+        // A malformed element in the UK set rejects the whole reply (a partial
+        // forensic set silently omits an index) — also a service fault.
+        assert_eq!(
+            interpret_reply(
+                Ok(reply(
+                    200,
+                    r#"{"UK":["000102030405060708090a0b0c0d0e0f","zz"]}"#
+                )),
+                &BareCtx,
+                1
+            )
+            .expect_err("a malformed key in the set is not an answer")
+            .code(),
+            libfreemkv::error::E_KEY_SERVICE_UNAVAILABLE,
+        );
+    }
+
+    /// Regression pin (passes before and after): a service that DOES hold the
+    /// key still resolves it, and array order is preserved as the forensic index
+    /// order. The Result-returning signature must not have changed the happy path.
+    #[test]
+    fn service_with_a_key_still_resolves_it_in_order() {
+        let keys = interpret_reply(
+            Ok(reply(
+                200,
+                r#"{"UK":["000102030405060708090a0b0c0d0e0f","0f0e0d0c0b0a09080706050403020100"]}"#,
+            )),
+            &BareCtx,
+            1,
+        )
+        .expect("a 200 carrying keys resolves");
+        assert_eq!(keys.len(), 2);
+        assert_eq!(keys[0].idx, 0);
+        assert_eq!(keys[1].idx, 1);
+        assert_eq!(keys[0].key[0], 0x00);
+        assert_eq!(keys[1].key[0], 0x0f);
+    }
+
+    /// A URL that fails the ADDRESS guard is operator configuration, not the
+    /// service being down — the two must stay separable, since only one of them
+    /// is worth retrying.
+    #[test]
+    fn address_guard_rejections_are_config_not_unreachable() {
+        for url in [
+            "http://127.0.0.1/keys",
+            "http://169.254.169.254/latest/meta-data/",
+            "ftp://example.com/keys",
+            "not a url",
+            "",
+        ] {
+            assert_eq!(
+                resolve_and_guard(url).expect_err("must be rejected").0,
+                GuardFail::Config,
+                "{url} is a configuration fault, not an outage"
+            );
+        }
+    }
+
     /// Finding #9 regression: parse_uk must reject any non-hex byte up front so
     /// sign prefixes / whitespace can't slip through the windowed 2-char parse
     /// (`u8::from_str_radix` accepts "+5", "-A", etc.).

tests/key_sources.rs

@@ -1,8 +1,8 @@
 //! Fixture-based integration tests for the published key sources.
 //!
 //! These exercise the *public* surface of `freemkv-keysources` end-to-end —
-//! real files on disk, the real `KeyDb`/`Mapfile` parsers from libfreemkv, and
-//! the `KeySource` trait (`get_uk` over a `ResolveCtx`) the applications drive.
+//! real files on disk, the real `KeyDb` parser from libfreemkv, and
+//! the `KeySource` trait (`get_unit_keys` over a `ResolveCtx`) the applications drive.
 //!
 //! Covered:
 //! - `KeydbSource`: terminal unit-key lookup by disc hash through a real
@@ -71,8 +71,8 @@ fn inputs(hash: &str) -> DiscInputs {
 /// Resolve a source through the public trait over a `DiscInputsCtx`.
 fn resolve(src: &dyn KeySource, inp: &DiscInputs) -> Vec<UnitKey> {
     let ctx = DiscInputsCtx::new(inp);
-    src.get_uk(&ctx)
-        .expect("get_uk must not error for these fixtures")
+    src.get_unit_keys(&ctx)
+        .expect("get_unit_keys must not error for these fixtures")
 }
 
 // ── KeydbSource: real-file lookup by disc hash ──────────────────────────────
@@ -130,7 +130,7 @@ fn keydb_source_missing_file_is_silent_ok_empty() {
     let inp = inputs(DISC_HASH);
     let ctx = DiscInputsCtx::new(&inp);
     assert!(
-        src.get_uk(&ctx)
+        src.get_unit_keys(&ctx)
             .expect("missing keydb is Ok, not Err")
             .is_empty()
     );
@@ -258,7 +258,7 @@ impl ScriptedSource {
 }
 
 impl KeySource for ScriptedSource {
-    fn get_uk(&self, _ctx: &dyn ResolveCtx) -> Result<Vec<UnitKey>, libfreemkv::Error> {
+    fn get_unit_keys(&self, _ctx: &dyn ResolveCtx) -> Result<Vec<UnitKey>, libfreemkv::Error> {
         Ok(self.keys.clone())
     }
     fn label(&self) -> &'static str {