Expose full AACS state: version, key source, disc hash, all keys public

- AacsState now exposes: version (1/2), bus_encryption, mkb_version, disc_hash, key_source (KeyDb/KeyDbDerived/ProcessingKey/DeviceKey), vuk, unit_keys, read_data_key, volume_id - All keys are public — apps that contribute to KEYDB ecosystem can read VUK, unit keys, Volume ID, disc hash for database submission - resolve_keys reports which path succeeded (key_source 1-4) - Cleaned up resolve_keys with shared builder to reduce duplication
2026-04-07 11:25:04 -07:00
parent bac2e39ee5
commit 193b571967
2 changed files with 82 additions and 61 deletions
@@ -858,6 +858,8 @@ pub struct ResolvedKeys {
    pub aacs2: bool,
    /// Whether bus encryption is enabled (from Content Certificate)
    pub bus_encryption: bool,
+    /// Which resolution path succeeded (1=KEYDB, 2=KEYDB derived, 3=PK, 4=DK)
+    pub key_source: u8,
 }

 /// Resolve all AACS keys for a disc given:
@@ -893,22 +895,26 @@ pub fn resolve_keys(

    let hash_hex = disc_hash_hex(&uk_file.disc_hash);

-    // Path 1: Look up VUK by disc hash in KEYDB
-    if let Some(entry) = keydb.find_disc(&hash_hex) {
-        if let Some(vuk) = entry.vuk {
-            // Decrypt unit keys with VUK
+    // Helper to build result
+    let build = |vuk: [u8; 16], key_source: u8| -> ResolvedKeys {
        let unit_keys: Vec<(u32, [u8; 16])> = uk_file.encrypted_keys.iter()
            .map(|(num, enc_key)| (*num, decrypt_unit_key(&vuk, enc_key)))
            .collect();
-
-            return Some(ResolvedKeys {
+        ResolvedKeys {
            disc_hash: uk_file.disc_hash,
            vuk,
            unit_keys,
-                title_cps_unit: uk_file.title_cps_unit,
+            title_cps_unit: uk_file.title_cps_unit.clone(),
            aacs2,
            bus_encryption,
-            });
+            key_source,
+        }
+    };
+
+    // Path 1: Look up VUK by disc hash in KEYDB
+    if let Some(entry) = keydb.find_disc(&hash_hex) {
+        if let Some(vuk) = entry.vuk {
+            return Some(build(vuk, 1));
        }
    }

@@ -916,19 +922,7 @@ pub fn resolve_keys(
    for entry in keydb.disc_entries.values() {
        if let (Some(mk), Some(did)) = (entry.media_key, entry.disc_id) {
            if did == *volume_id {
-                let vuk = derive_vuk(&mk, volume_id);
-                let unit_keys: Vec<(u32, [u8; 16])> = uk_file.encrypted_keys.iter()
-                    .map(|(num, enc_key)| (*num, decrypt_unit_key(&vuk, enc_key)))
-                    .collect();
-
-                return Some(ResolvedKeys {
-                    disc_hash: uk_file.disc_hash,
-                    vuk,
-                    unit_keys,
-                    title_cps_unit: uk_file.title_cps_unit,
-                    aacs2,
-                    bus_encryption,
-                });
+                return Some(build(derive_vuk(&mk, volume_id), 2));
            }
        }
    }
@@ -936,36 +930,12 @@ pub fn resolve_keys(
    // Path 3: MKB + processing keys → media key → VUK
    if let Some(mkb) = mkb_data {
        if let Some(mk) = derive_media_key_from_pk(mkb, &keydb.processing_keys) {
-            let vuk = derive_vuk(&mk, volume_id);
-            let unit_keys: Vec<(u32, [u8; 16])> = uk_file.encrypted_keys.iter()
-                .map(|(num, enc_key)| (*num, decrypt_unit_key(&vuk, enc_key)))
-                .collect();
-
-            return Some(ResolvedKeys {
-                disc_hash: uk_file.disc_hash,
-                vuk,
-                unit_keys,
-                title_cps_unit: uk_file.title_cps_unit,
-                aacs2,
-                bus_encryption,
-            });
+            return Some(build(derive_vuk(&mk, volume_id), 3));
        }

        // Path 4: MKB + device keys → processing key → media key → VUK
        if let Some(mk) = derive_media_key_from_dk(mkb, &keydb.device_keys) {
-            let vuk = derive_vuk(&mk, volume_id);
-            let unit_keys: Vec<(u32, [u8; 16])> = uk_file.encrypted_keys.iter()
-                .map(|(num, enc_key)| (*num, decrypt_unit_key(&vuk, enc_key)))
-                .collect();
-
-            return Some(ResolvedKeys {
-                disc_hash: uk_file.disc_hash,
-                vuk,
-                unit_keys,
-                title_cps_unit: uk_file.title_cps_unit,
-                aacs2,
-                bus_encryption,
-            });
+            return Some(build(derive_vuk(&mk, volume_id), 4));
        }
    }

@@ -256,14 +256,48 @@ impl Stream {
 /// AACS decryption state for a disc.
 #[derive(Debug)]
 pub struct AacsState {
-    /// Volume Unique Key
-    pub vuk: [u8; 16],
-    /// Decrypted unit keys indexed by CPS unit number
-    pub unit_keys: Vec<(u32, [u8; 16])>,
-    /// Read data key (AACS 2.0 bus decryption) — None for AACS 1.0
-    pub read_data_key: Option<[u8; 16]>,
-    /// Whether bus encryption is enabled
+    /// AACS version (1 or 2)
+    pub version: u8,
+    /// Whether bus encryption is enabled (always true for AACS 2.0 / UHD)
    pub bus_encryption: bool,
+    /// MKB version from disc (e.g. 68, 77)
+    pub mkb_version: Option<u32>,
+    /// Disc hash (SHA1 of Unit_Key_RO.inf) — hex string with 0x prefix
+    pub disc_hash: String,
+    /// How keys were resolved
+    pub key_source: KeySource,
+    /// Volume Unique Key (16 bytes)
+    pub vuk: [u8; 16],
+    /// Decrypted unit keys (CPS unit number, key)
+    pub unit_keys: Vec<(u32, [u8; 16])>,
+    /// Read data key for AACS 2.0 bus decryption — None for AACS 1.0
+    pub read_data_key: Option<[u8; 16]>,
+    /// Volume ID (16 bytes) — from SCSI handshake
+    pub volume_id: [u8; 16],
+}
+
+/// How AACS keys were resolved.
+#[derive(Debug, Clone, Copy, PartialEq)]
+pub enum KeySource {
+    /// VUK found directly in KEYDB by disc hash
+    KeyDb,
+    /// Media key + Volume ID from KEYDB → derived VUK
+    KeyDbDerived,
+    /// MKB + processing keys → media key → VUK
+    ProcessingKey,
+    /// MKB + device keys → subset-difference tree → VUK
+    DeviceKey,
+}
+
+impl KeySource {
+    pub fn name(&self) -> &'static str {
+        match self {
+            KeySource::KeyDb => "KEYDB",
+            KeySource::KeyDbDerived => "KEYDB (derived)",
+            KeySource::ProcessingKey => "MKB + processing key",
+            KeySource::DeviceKey => "MKB + device key",
+        }
+    }
 }

 // ─── Disc scanning ──────────────────────────────────────────────────────────
@@ -428,21 +462,38 @@ impl Disc {
        //   Path 1: disc hash → KEYDB → VUK (fast, 99% of discs)
        //   Path 2: KEYDB media key + VID → VUK
        //   Path 3: MKB + processing keys → media key → VUK (fallback)
+        // Read MKB from drive
+        let mkb_data = aacs::read_mkb_from_drive(session).ok();
+        let mkb_ver = mkb_data.as_deref().and_then(aacs::mkb_version);
+
        let resolved = aacs::resolve_keys(
            &uk_ro_data,
            cc_data.as_deref(),
            &vid,
            &keydb,
-            aacs::read_mkb_from_drive(session).ok().as_deref(),
+            mkb_data.as_deref(),
        ).ok_or_else(|| Error::AacsError {
            detail: "failed to resolve AACS keys".into(),
        })?;

+        let key_source = match resolved.key_source {
+            1 => KeySource::KeyDb,
+            2 => KeySource::KeyDbDerived,
+            3 => KeySource::ProcessingKey,
+            4 => KeySource::DeviceKey,
+            _ => KeySource::KeyDb,
+        };
+
        Ok(AacsState {
+            version: if resolved.aacs2 { 2 } else { 1 },
+            bus_encryption: resolved.bus_encryption,
+            mkb_version: mkb_ver,
+            disc_hash: aacs::disc_hash_hex(&resolved.disc_hash),
+            key_source,
            vuk: resolved.vuk,
            unit_keys: resolved.unit_keys,
            read_data_key,
-            bus_encryption: resolved.bus_encryption,
+            volume_id: vid,
        })
    }