Merge pull request #226 from mozilla/bug-1641972-fixes

Miscellaneous fixes related to bug investigation

Author: baumanj

mp4parse/src/lib.rs

@@ -214,6 +214,8 @@ pub type Result<T> = std::result::Result<T, Error>;
 /// begins with a header describing the length of the box's data and a
 /// four-byte box type which identifies the type of the box. Together these
 /// are enough to interpret the contents of that section of the file.
+///
+/// See ISO 14496-12:2015 § 4.2
 #[derive(Debug, Clone, Copy)]
 struct BoxHeader {
     /// Box type.
@@ -226,6 +228,11 @@ struct BoxHeader {
     uuid: Option<[u8; 16]>,
 }
 
+impl BoxHeader {
+    const MIN_SIZE: u64 = 8; // 4-byte size + 4-byte type
+    const MIN_LARGE_SIZE: u64 = 16; // 4-byte size + 4-byte type + 16-byte size
+}
+
 /// File type box 'ftyp'.
 #[derive(Debug)]
 struct FileTypeBox {
@@ -367,6 +374,8 @@ pub enum SampleEntry {
     Unknown,
 }
 
+/// An Elementary Stream Descriptor
+/// See ISO 14496-1:2010 § 7.2.6.5
 #[allow(non_camel_case_types)]
 #[derive(Debug, Default)]
 pub struct ES_Descriptor {
@@ -1007,6 +1016,7 @@ impl Track {
     }
 }
 
+/// See ISO 14496-12:2015 § 4.2
 struct BMFFBox<'a, T: 'a> {
     head: BoxHeader,
     content: Take<&'a mut T>,
@@ -1115,6 +1125,8 @@ impl<'a, T> Drop for BMFFBox<'a, T> {
 /// and its length. Used internally for dispatching to specific
 /// parsers for the internal content, or to get the length to
 /// skip unknown or uninteresting boxes.
+///
+/// See ISO 14496-12:2015 § 4.2
 fn read_box_header<T: ReadBytesExt>(src: &mut T) -> Result<BoxHeader> {
     let size32 = be_u32(src)?;
     let name = BoxType::from(be_u32(src)?);
@@ -1123,17 +1135,21 @@ fn read_box_header<T: ReadBytesExt>(src: &mut T) -> Result<BoxHeader> {
         0 => return Err(Error::Unsupported("unknown sized box")),
         1 => {
             let size64 = be_u64(src)?;
-            if size64 < 16 {
+            if size64 < BoxHeader::MIN_LARGE_SIZE {
                 return Err(Error::InvalidData("malformed wide size"));
             }
             size64
         }
-        2..=7 => return Err(Error::InvalidData("malformed size")),
-        _ => u64::from(size32),
+        _ => {
+            if u64::from(size32) < BoxHeader::MIN_SIZE {
+                return Err(Error::InvalidData("malformed size"));
+            }
+            u64::from(size32)
+        }
     };
     let mut offset = match size32 {
-        1 => 4 + 4 + 8,
-        _ => 4 + 4,
+        1 => BoxHeader::MIN_LARGE_SIZE,
+        _ => BoxHeader::MIN_SIZE,
     };
     let uuid = if name == BoxType::UuidBox {
         if size >= offset + 16 {
@@ -2389,6 +2405,7 @@ fn read_flac_metadata<T: Read>(src: &mut BMFFBox<T>) -> Result<FLACMetadataBlock
     Ok(FLACMetadataBlock { block_type, data })
 }
 
+/// See ISO 14496-1:2010 § 7.2.6.5
 fn find_descriptor(data: &[u8], esds: &mut ES_Descriptor) -> Result<()> {
     // Tags for elementary stream description
     const ESDESCR_TAG: u8 = 0x03;
@@ -2402,6 +2419,8 @@ fn find_descriptor(data: &[u8], esds: &mut ES_Descriptor) -> Result<()> {
         let des = &mut Cursor::new(remains);
         let tag = des.read_u8()?;
 
+        // See ISO 14496-1:2010 § 8.3.3 for interpreting size of exandable classes
+
         let mut end: u32 = 0; // It's u8 without declaration type that is incorrect.
                               // MSB of extend_or_len indicates more bytes, up to 4 bytes.
         for _ in 0..4 {
@@ -2413,7 +2432,7 @@ fn find_descriptor(data: &[u8], esds: &mut ES_Descriptor) -> Result<()> {
             }
             let extend_or_len = des.read_u8()?;
             end = (end << 7) + u32::from(extend_or_len & 0x7F);
-            if (extend_or_len & 0x80) == 0 {
+            if (extend_or_len & 0b1000_0000) == 0 {
                 end += des.position() as u32;
                 break;
             }
@@ -2441,6 +2460,7 @@ fn find_descriptor(data: &[u8], esds: &mut ES_Descriptor) -> Result<()> {
         }
 
         remains = &remains[end.to_usize()..remains.len()];
+        debug!("remains.len(): {}", remains.len());
     }
 
     Ok(())
@@ -2457,6 +2477,7 @@ fn get_audio_object_type(bit_reader: &mut BitReader) -> Result<u16> {
     Ok(audio_object_type)
 }
 
+/// See ISO 14496-1:2010 § 7.2.6.7 and probably 14496-3 somewhere?
 fn read_ds_descriptor(data: &[u8], esds: &mut ES_Descriptor) -> Result<()> {
     let frequency_table = vec![
         (0x0, 96000),
@@ -2623,6 +2644,7 @@ fn read_surround_channel_count(bit_reader: &mut BitReader, channels: u8) -> Resu
     Ok(count)
 }
 
+/// See ISO 14496-1:2010 § 7.2.6.6
 fn read_dc_descriptor(data: &[u8], esds: &mut ES_Descriptor) -> Result<()> {
     let des = &mut Cursor::new(data);
     let object_profile = des.read_u8()?;
@@ -2643,6 +2665,7 @@ fn read_dc_descriptor(data: &[u8], esds: &mut ES_Descriptor) -> Result<()> {
     Ok(())
 }
 
+/// See ISO 14496-1:2010 § 7.2.6.5
 fn read_es_descriptor(data: &[u8], esds: &mut ES_Descriptor) -> Result<()> {
     let des = &mut Cursor::new(data);
 
@@ -2673,14 +2696,7 @@ fn read_es_descriptor(data: &[u8], esds: &mut ES_Descriptor) -> Result<()> {
 fn read_esds<T: Read>(src: &mut BMFFBox<T>) -> Result<ES_Descriptor> {
     let (_, _) = read_fullbox_extra(src)?;
 
-    // Subtract 4 extra to offset the members of fullbox not accounted for in
-    // head.offset
-    let esds_size = src
-        .head
-        .size
-        .checked_sub(src.head.offset + 4)
-        .expect("offset invalid");
-    let esds_array = read_buf(src, esds_size)?;
+    let esds_array = read_buf(src, src.bytes_left())?;
 
     let mut es_data = ES_Descriptor::default();
     find_descriptor(&esds_array, &mut es_data)?;
@@ -2983,6 +2999,7 @@ fn read_qt_wave_atom<T: Read>(src: &mut BMFFBox<T>) -> Result<ES_Descriptor> {
 }
 
 /// Parse an audio description inside an stsd box.
+/// See ISO 14496-12:2015 § 12.2.3
 fn read_audio_sample_entry<T: Read>(src: &mut BMFFBox<T>) -> Result<SampleEntry> {
     let name = src.get_header().name;
 
@@ -3115,6 +3132,7 @@ fn read_audio_sample_entry<T: Read>(src: &mut BMFFBox<T>) -> Result<SampleEntry>
 }
 
 /// Parse a stsd box.
+/// See ISO 14496-12:2015 § 8.5.2
 fn read_stsd<T: Read>(src: &mut BMFFBox<T>, track: &mut Track) -> Result<SampleDescriptionBox> {
     let (_, _) = read_fullbox_extra(src)?;
 

mp4parse_capi/examples/dump.rs

@@ -34,7 +34,7 @@ fn dump_file(filename: &str) {
         match rv {
             Mp4parseStatus::Ok => (),
             _ => {
-                println!("-- fail to parse, '-v' for more info");
+                println!("-- fail to parse: {:?}, '-v' for more info", rv);
                 return;
             }
         }
@@ -44,8 +44,8 @@ fn dump_file(filename: &str) {
             Mp4parseStatus::Ok => {
                 println!("-- mp4parse_fragment_info {:?}", frag_info);
             }
-            _ => {
-                println!("-- mp4parse_fragment_info failed");
+            rv => {
+                println!("-- mp4parse_fragment_info failed with {:?}", rv);
                 return;
             }
         }