Merge pull request #1015 from kamaroyl:feat/PsshVersion1

PiperOrigin-RevId: 603016920

libraries/extractor/src/main/java/androidx/media3/extractor/mp4/PsshAtomUtil.java

@@ -72,7 +72,9 @@ public final class PsshAtomUtil {
     if (data != null && data.length != 0) {
       psshBox.putInt(data.length);
       psshBox.put(data);
-    } // Else the last 4 bytes are a 0 DataSize.
+    } else {
+      psshBox.putInt(0);
+    }
     return psshBox.array();
   }
 
@@ -152,23 +154,25 @@ public final class PsshAtomUtil {
    * @return The parsed PSSH atom. Null if the input is not a valid PSSH atom, or if the PSSH atom
    *     has an unsupported version.
    */
-  // TODO: Support parsing of the key ids for version 1 PSSH atoms.
   @Nullable
-  private static PsshAtom parsePsshAtom(byte[] atom) {
+  public static PsshAtom parsePsshAtom(byte[] atom) {
     ParsableByteArray atomData = new ParsableByteArray(atom);
     if (atomData.limit() < Atom.FULL_HEADER_SIZE + 16 /* UUID */ + 4 /* DataSize */) {
       // Data too short.
       return null;
     }
     atomData.setPosition(0);
+    int bufferLength = atomData.bytesLeft();
     int atomSize = atomData.readInt();
-    if (atomSize != atomData.bytesLeft() + 4) {
+    if (atomSize != bufferLength) {
-      // Not an atom, or incorrect atom size.
+      Log.w(
+          TAG,
+          "Advertised atom size (" + atomSize + ") does not match buffer size: " + bufferLength);
       return null;
     }
     int atomType = atomData.readInt();
     if (atomType != Atom.TYPE_pssh) {
-      // Not an atom, or incorrect atom type.
+      Log.w(TAG, "Atom type is not pssh: " + atomType);
       return null;
     }
     int atomVersion = Atom.parseFullAtomVersion(atomData.readInt());
@@ -177,31 +181,46 @@ public final class PsshAtomUtil {
       return null;
     }
     UUID uuid = new UUID(atomData.readLong(), atomData.readLong());
+    UUID[] keyIds = null;
     if (atomVersion == 1) {
       int keyIdCount = atomData.readUnsignedIntToInt();
-      atomData.skipBytes(16 * keyIdCount);
+      keyIds = new UUID[keyIdCount];
+      for (int i = 0; i < keyIdCount; ++i) {
+        keyIds[i] = new UUID(atomData.readLong(), atomData.readLong());
+      }
     }
     int dataSize = atomData.readUnsignedIntToInt();
-    if (dataSize != atomData.bytesLeft()) {
+    bufferLength = atomData.bytesLeft();
-      // Incorrect dataSize.
+    if (dataSize != bufferLength) {
+      Log.w(
+          TAG, "Atom data size (" + dataSize + ") does not match the bytes left: " + bufferLength);
       return null;
     }
     byte[] data = new byte[dataSize];
     atomData.readBytes(data, 0, dataSize);
-    return new PsshAtom(uuid, atomVersion, data);
+    return new PsshAtom(uuid, atomVersion, data, keyIds);
   }
 
-  // TODO: Consider exposing this and making parsePsshAtom public.
+  /** A class representing the mp4 PSSH Atom as specified in ISO/IEC 23001-7. */
-  private static class PsshAtom {
+  public static final class PsshAtom {
 
-    private final UUID uuid;
+    /** The UUID of the encryption system as specified in ISO/IEC 23009-1 section 5.8.4.1. */
-    private final int version;
+    public final UUID uuid;
-    private final byte[] schemeData;
 
-    public PsshAtom(UUID uuid, int version, byte[] schemeData) {
+    /** The version of the PSSH atom, either 0 or 1. */
+    public final int version;
+
+    /** Binary scheme data. */
+    public final byte[] schemeData;
+
+    /** Array of key IDs. Always null for version 0 and non-null for version 1. */
+    @Nullable public final UUID[] keyIds;
+
+    /* package */ PsshAtom(UUID uuid, int version, byte[] schemeData, @Nullable UUID[] keyIds) {
       this.uuid = uuid;
       this.version = version;
       this.schemeData = schemeData;
+      this.keyIds = keyIds;
     }
   }
 }

libraries/extractor/src/test/java/androidx/media3/extractor/mp4/PsshAtomUtilTest.java

@@ -33,10 +33,11 @@ import org.junit.runner.RunWith;
 public final class PsshAtomUtilTest {
 
   @Test
-  public void buildPsshAtom() {
+  public void buildPsshAtom_version0_returnsCorrectBytes() {
     byte[] schemeData = new byte[] {0, 1, 2, 3, 4, 5};
+
     byte[] psshAtom = PsshAtomUtil.buildPsshAtom(C.WIDEVINE_UUID, schemeData);
-    // Read the PSSH atom back and assert its content is as expected.
+
     ParsableByteArray parsablePsshAtom = new ParsableByteArray(psshAtom);
     assertThat(parsablePsshAtom.readUnsignedIntToInt()).isEqualTo(psshAtom.length); // length
     assertThat(parsablePsshAtom.readInt()).isEqualTo(TYPE_pssh); // type
@@ -50,4 +51,208 @@ public final class PsshAtomUtilTest {
     parsablePsshAtom.readBytes(psshSchemeData, 0, schemeData.length);
     assertThat(psshSchemeData).isEqualTo(schemeData);
   }
+
+  @Test
+  public void buildPsshAtom_version1_returnsCorrectBytes() {
+    byte[] schemeData = new byte[] {0, 1, 2, 3, 4, 5};
+    UUID[] keyIds = new UUID[2];
+    keyIds[0] = UUID.fromString("edef8ba9-79d6-4ace-a3c8-27dcd51d21ed");
+    keyIds[1] = UUID.fromString("dc03d7f3-334d-b858-f114-9ab759a925fb");
+
+    byte[] psshAtom = PsshAtomUtil.buildPsshAtom(C.WIDEVINE_UUID, keyIds, schemeData);
+
+    ParsableByteArray parsablePsshAtom = new ParsableByteArray(psshAtom);
+    assertThat(parsablePsshAtom.readUnsignedIntToInt()).isEqualTo(psshAtom.length);
+    assertThat(parsablePsshAtom.readInt()).isEqualTo(TYPE_pssh); // type
+    int fullAtomInt = parsablePsshAtom.readInt(); // version + flags
+    assertThat(parseFullAtomVersion(fullAtomInt)).isEqualTo(1);
+    assertThat(parseFullAtomFlags(fullAtomInt)).isEqualTo(0);
+    UUID systemId = new UUID(parsablePsshAtom.readLong(), parsablePsshAtom.readLong());
+    assertThat(systemId).isEqualTo(WIDEVINE_UUID);
+    assertThat(parsablePsshAtom.readUnsignedIntToInt()).isEqualTo(2);
+    UUID keyId0 = new UUID(parsablePsshAtom.readLong(), parsablePsshAtom.readLong());
+    assertThat(keyId0).isEqualTo(keyIds[0]);
+    UUID keyId1 = new UUID(parsablePsshAtom.readLong(), parsablePsshAtom.readLong());
+    assertThat(keyId1).isEqualTo(keyIds[1]);
+    assertThat(parsablePsshAtom.readUnsignedIntToInt()).isEqualTo(schemeData.length);
+    byte[] psshSchemeData = new byte[schemeData.length];
+    parsablePsshAtom.readBytes(psshSchemeData, 0, schemeData.length);
+    assertThat(psshSchemeData).isEqualTo(schemeData);
+  }
+
+  @Test
+  public void parsePsshAtom_version0_parsesCorrectData() {
+    byte[] psshBuffer = {
+      // BMFF box header (36 bytes, 'pssh')
+      0x00,
+      0x00,
+      0x00,
+      0x24,
+      0x70,
+      0x73,
+      0x73,
+      0x68,
+      // Full box header (version = 0, flags = 0)
+      0x00,
+      0x00,
+      0x00,
+      0x00,
+      // SystemID
+      0x10,
+      0x77,
+      -0x11,
+      -0x14,
+      -0x40,
+      -0x4e,
+      0x4d,
+      0x02,
+      -0x54,
+      -0x1d,
+      0x3c,
+      0x1e,
+      0x52,
+      -0x1e,
+      -0x05,
+      0x4b,
+      // Size of Data (4)
+      0x00,
+      0x00,
+      0x00,
+      0x04,
+      // Data bytes
+      0x1a,
+      0x1b,
+      0x1c,
+      0x1d
+    };
+
+    PsshAtomUtil.PsshAtom psshAtom = PsshAtomUtil.parsePsshAtom(psshBuffer);
+
+    assertThat(psshAtom).isNotNull();
+    assertThat(psshAtom.version).isEqualTo(0);
+    assertThat(psshAtom.uuid).isEqualTo(UUID.fromString("1077efec-c0b2-4d02-ace3-3c1e52e2fb4b"));
+    assertThat(psshAtom.keyIds).isNull();
+    assertThat(psshAtom.schemeData).isEqualTo(new byte[] {0x1a, 0x1b, 0x1c, 0x1d});
+  }
+
+  @Test
+  public void parsePsshAtom_version1_parsesCorrectData() {
+    byte[] psshBuffer = {
+      // BMFF box header (68 bytes, 'pssh')
+      0x00,
+      0x00,
+      0x00,
+      0x44,
+      0x70,
+      0x73,
+      0x73,
+      0x68,
+      // Full box header (version = 1, flags = 0)
+      0x01,
+      0x00,
+      0x00,
+      0x00,
+      // SystemID
+      0x10,
+      0x77,
+      -0x11,
+      -0x14,
+      -0x40,
+      -0x4e,
+      0x4d,
+      0x02,
+      -0x54,
+      -0x1d,
+      0x3c,
+      0x1e,
+      0x52,
+      -0x1e,
+      -0x05,
+      0x4b,
+      // KID_count (2)
+      0x00,
+      0x00,
+      0x00,
+      0x02,
+      // First KID ("0123456789012345")
+      0x30,
+      0x31,
+      0x32,
+      0x33,
+      0x34,
+      0x35,
+      0x36,
+      0x37,
+      0x38,
+      0x39,
+      0x30,
+      0x31,
+      0x32,
+      0x33,
+      0x34,
+      0x35,
+      // Second KID ("ABCDEFGHIJKLMNOP")
+      0x41,
+      0x42,
+      0x43,
+      0x44,
+      0x45,
+      0x46,
+      0x47,
+      0x48,
+      0x49,
+      0x4a,
+      0x4b,
+      0x4c,
+      0x4d,
+      0x4e,
+      0x4f,
+      0x50,
+      // Size of Data (0)
+      0x00,
+      0x00,
+      0x00,
+      0x00,
+    };
+
+    PsshAtomUtil.PsshAtom psshAtom = PsshAtomUtil.parsePsshAtom(psshBuffer);
+
+    assertThat(psshAtom).isNotNull();
+    assertThat(psshAtom.version).isEqualTo(1);
+    assertThat(psshAtom.uuid).isEqualTo(UUID.fromString("1077efec-c0b2-4d02-ace3-3c1e52e2fb4b"));
+    assertThat(psshAtom.keyIds).isNotNull();
+    assertThat(psshAtom.keyIds).hasLength(2);
+    assertThat(psshAtom.schemeData).isEmpty();
+  }
+
+  @Test
+  public void parsePsshAtom_version0FromBuildPsshAtom_returnsEqualData() {
+    byte[] schemeData = new byte[] {0, 1, 2, 3, 4, 5};
+
+    PsshAtomUtil.PsshAtom parsedAtom =
+        PsshAtomUtil.parsePsshAtom(PsshAtomUtil.buildPsshAtom(C.WIDEVINE_UUID, schemeData));
+
+    assertThat(parsedAtom).isNotNull();
+    assertThat(parsedAtom.version).isEqualTo(0);
+    assertThat(parsedAtom.keyIds).isNull();
+    assertThat(parsedAtom.uuid).isEqualTo(C.WIDEVINE_UUID);
+    assertThat(parsedAtom.schemeData).isEqualTo(new byte[] {0, 1, 2, 3, 4, 5});
+  }
+
+  @Test
+  public void parsePsshAtom_version1FromBuildPsshAtom_returnsEqualData() {
+    byte[] schemeData = new byte[] {0, 1, 2, 3, 4, 5};
+    UUID[] keyIds = new UUID[2];
+    keyIds[0] = UUID.fromString("edef8ba9-79d6-4ace-a3c8-27dcd51d21ed");
+    keyIds[1] = UUID.fromString("dc03d7f3-334d-b858-f114-9ab759a925fb");
+
+    PsshAtomUtil.PsshAtom parsedAtom =
+        PsshAtomUtil.parsePsshAtom(PsshAtomUtil.buildPsshAtom(C.WIDEVINE_UUID, keyIds, schemeData));
+
+    assertThat(parsedAtom).isNotNull();
+    assertThat(parsedAtom.version).isEqualTo(1);
+    assertThat(parsedAtom.keyIds).isEqualTo(keyIds);
+    assertThat(parsedAtom.uuid).isEqualTo(C.WIDEVINE_UUID);
+    assertThat(parsedAtom.schemeData).isEqualTo(new byte[] {0, 1, 2, 3, 4, 5});
+  }
 }