mp4: Skip unexpected or empty "data" ilst atoms

This commit is contained in:
Uwe Klotz 2023-10-02 13:50:37 +02:00 committed by Alex
parent be0f24b9e6
commit 2b814cdc4a
4 changed files with 95 additions and 36 deletions

View file

@ -782,7 +782,7 @@ mod tests {
let cursor = Cursor::new(tag);
let mut reader = AtomReader::new(cursor).unwrap();
super::read::parse_ilst(&mut reader, len as u64).unwrap()
super::read::parse_ilst(&mut reader, crate::ParsingMode::Strict, len as u64).unwrap()
}
fn verify_atom(ilst: &Ilst, ident: [u8; 4], data: &AtomData) {
@ -850,7 +850,8 @@ mod tests {
let cursor = Cursor::new(tag);
let mut reader = AtomReader::new(cursor).unwrap();
let parsed_tag = super::read::parse_ilst(&mut reader, len as u64).unwrap();
let parsed_tag =
super::read::parse_ilst(&mut reader, crate::ParsingMode::Strict, len as u64).unwrap();
assert_eq!(expected_tag, parsed_tag);
}
@ -866,8 +867,12 @@ mod tests {
let mut reader = AtomReader::new(cursor).unwrap();
// Remove the ilst identifier and size
let temp_parsed_tag =
super::read::parse_ilst(&mut reader, (writer.len() - 8) as u64).unwrap();
let temp_parsed_tag = super::read::parse_ilst(
&mut reader,
crate::ParsingMode::Strict,
(writer.len() - 8) as u64,
)
.unwrap();
assert_eq!(parsed_tag, temp_parsed_tag);
}
@ -880,7 +885,8 @@ mod tests {
let cursor = Cursor::new(tag);
let mut reader = AtomReader::new(cursor).unwrap();
let ilst = super::read::parse_ilst(&mut reader, len as u64).unwrap();
let ilst =
super::read::parse_ilst(&mut reader, crate::ParsingMode::Strict, len as u64).unwrap();
let tag: Tag = ilst.into();
@ -999,7 +1005,12 @@ mod tests {
let cursor = Cursor::new(ilst_bytes);
let mut reader = AtomReader::new(cursor).unwrap();
ilst = super::read::parse_ilst(&mut reader, ilst_bytes.len() as u64).unwrap();
ilst = super::read::parse_ilst(
&mut reader,
crate::ParsingMode::Strict,
ilst_bytes.len() as u64,
)
.unwrap();
}
let mut file = tempfile::tempfile().unwrap();

View file

@ -10,11 +10,16 @@ use crate::mp4::ilst::atom::AtomDataStorage;
use crate::mp4::read::{skip_unneeded, AtomReader};
use crate::picture::{MimeType, Picture, PictureType};
use crate::util::text::utf16_decode;
use crate::ParsingMode;
use std::borrow::Cow;
use std::io::{Cursor, Read, Seek, SeekFrom};
pub(in crate::mp4) fn parse_ilst<R>(reader: &mut AtomReader<R>, len: u64) -> Result<Ilst>
pub(in crate::mp4) fn parse_ilst<R>(
reader: &mut AtomReader<R>,
parsing_mode: ParsingMode,
len: u64,
) -> Result<Ilst>
where
R: Read + Seek,
{
@ -35,12 +40,14 @@ where
continue;
},
b"covr" => {
handle_covr(&mut ilst_reader, &mut tag, &atom)?;
handle_covr(&mut ilst_reader, parsing_mode, &mut tag, &atom)?;
continue;
},
// Upgrade this to a \xa9gen atom
b"gnre" => {
if let Some(atom_data) = parse_data_inner(&mut ilst_reader, &atom)? {
if let Some(atom_data) =
parse_data_inner(&mut ilst_reader, parsing_mode, &atom)?
{
let mut data = Vec::new();
for (_, content) in atom_data {
@ -70,7 +77,9 @@ where
// Special case the "Album ID", as it has the code "BE signed integer" (21), but
// must be interpreted as a "BE 64-bit Signed Integer" (74)
b"plID" => {
if let Some(atom_data) = parse_data_inner(&mut ilst_reader, &atom)? {
if let Some(atom_data) =
parse_data_inner(&mut ilst_reader, parsing_mode, &atom)?
{
let mut data = Vec::new();
for (code, content) in atom_data {
@ -98,7 +107,9 @@ where
continue;
},
b"cpil" | b"hdvd" | b"pcst" | b"pgap" | b"shwm" => {
if let Some(atom_data) = parse_data_inner(&mut ilst_reader, &atom)? {
if let Some(atom_data) =
parse_data_inner(&mut ilst_reader, parsing_mode, &atom)?
{
if let Some((_, content)) = atom_data.first() {
let data = match content[..] {
[0, ..] => AtomData::Bool(false),
@ -118,17 +129,22 @@ where
}
}
parse_data(&mut ilst_reader, &mut tag, atom)?;
parse_data(&mut ilst_reader, parsing_mode, &mut tag, atom)?;
}
Ok(tag)
}
fn parse_data<R>(reader: &mut AtomReader<R>, tag: &mut Ilst, atom_info: AtomInfo) -> Result<()>
fn parse_data<R>(
reader: &mut AtomReader<R>,
parsing_mode: ParsingMode,
tag: &mut Ilst,
atom_info: AtomInfo,
) -> Result<()>
where
R: Read + Seek,
{
if let Some(mut atom_data) = parse_data_inner(reader, &atom_info)? {
if let Some(mut atom_data) = parse_data_inner(reader, parsing_mode, &atom_info)? {
// Most atoms we encounter are only going to have 1 value, so store them as such
if atom_data.len() == 1 {
let (flags, content) = atom_data.remove(0);
@ -157,8 +173,11 @@ where
Ok(())
}
const DATA_ATOM_IDENT: AtomIdent<'static> = AtomIdent::Fourcc(*b"data");
fn parse_data_inner<R>(
reader: &mut AtomReader<R>,
parsing_mode: ParsingMode,
atom_info: &AtomInfo,
) -> Result<Option<Vec<(u32, Vec<u8>)>>>
where
@ -170,11 +189,7 @@ where
let to_read = (atom_info.start + atom_info.len) - reader.stream_position()?;
let mut pos = 0;
while pos < to_read {
let data_atom = reader.next()?;
match data_atom.ident {
AtomIdent::Fourcc(ref name) if name == b"data" => {},
_ => err!(BadAtom("Expected atom \"data\" to follow name")),
}
let next_atom = reader.next()?;
// We don't care about the version
let _version = reader.read_u8()?;
@ -187,17 +202,32 @@ where
// We don't care about the locale
reader.seek(SeekFrom::Current(4))?;
let content_len = (data_atom.len - 16) as usize;
if content_len == 0 {
// We won't add empty atoms
return Ok(None);
match next_atom.ident {
DATA_ATOM_IDENT => {
debug_assert!(next_atom.len >= 16);
let content_len = (next_atom.len - 16) as usize;
if content_len > 0 {
let mut content = try_vec![0; content_len];
reader.read_exact(&mut content)?;
ret.push((flags, content));
} else {
log::warn!("Skipping empty \"data\" atom");
}
},
_ => match parsing_mode {
ParsingMode::Strict => {
err!(BadAtom("Expected atom \"data\" to follow name"))
},
ParsingMode::BestAttempt | ParsingMode::Relaxed => {
log::warn!(
"Skipping unexpected atom {actual_ident:?}, expected {expected_ident:?}",
actual_ident = next_atom.ident,
expected_ident = DATA_ATOM_IDENT
)
},
},
}
let mut content = try_vec![0; content_len];
reader.read_exact(&mut content)?;
pos += data_atom.len;
ret.push((flags, content));
pos += next_atom.len;
}
let ret = if ret.is_empty() { None } else { Some(ret) };
@ -228,11 +258,16 @@ fn parse_int(bytes: &[u8]) -> Result<i32> {
})
}
fn handle_covr<R>(reader: &mut AtomReader<R>, tag: &mut Ilst, atom_info: &AtomInfo) -> Result<()>
fn handle_covr<R>(
reader: &mut AtomReader<R>,
parsing_mode: ParsingMode,
tag: &mut Ilst,
atom_info: &AtomInfo,
) -> Result<()>
where
R: Read + Seek,
{
if let Some(atom_data) = parse_data_inner(reader, atom_info)? {
if let Some(atom_data) = parse_data_inner(reader, parsing_mode, atom_info)? {
let mut data = Vec::new();
let len = atom_data.len();

View file

@ -4,6 +4,7 @@ use super::ilst::Ilst;
use super::read::{meta_is_full, nested_atom, skip_unneeded, AtomReader};
use crate::error::Result;
use crate::macros::decode_err;
use crate::ParsingMode;
use std::io::{Read, Seek};
@ -33,7 +34,11 @@ impl Moov {
moov.ok_or_else(|| decode_err!(Mp4, "No \"moov\" atom found"))
}
pub(super) fn parse<R>(reader: &mut AtomReader<R>, read_properties: bool) -> Result<Self>
pub(super) fn parse<R>(
reader: &mut AtomReader<R>,
parsing_mode: ParsingMode,
read_properties: bool,
) -> Result<Self>
where
R: Read + Seek,
{
@ -51,7 +56,7 @@ impl Moov {
}
},
b"udta" => {
meta = meta_from_udta(reader, atom.len - 8)?;
meta = meta_from_udta(reader, parsing_mode, atom.len - 8)?;
},
_ => skip_unneeded(reader, atom.extended, atom.len)?,
}
@ -66,7 +71,11 @@ impl Moov {
}
}
fn meta_from_udta<R>(reader: &mut AtomReader<R>, len: u64) -> Result<Option<Ilst>>
fn meta_from_udta<R>(
reader: &mut AtomReader<R>,
parsing_mode: ParsingMode,
len: u64,
) -> Result<Option<Ilst>>
where
R: Read + Seek,
{
@ -118,7 +127,7 @@ where
}
if found_ilst {
return parse_ilst(reader, ilst_atom_size - 8).map(Some);
return parse_ilst(reader, parsing_mode, ilst_atom_size - 8).map(Some);
}
Ok(None)

View file

@ -178,7 +178,11 @@ where
let moov_info = Moov::find(&mut reader)?;
reader.reset_bounds(moov_info.start + 8, moov_info.len - 8);
let moov = Moov::parse(&mut reader, parse_options.read_properties)?;
let moov = Moov::parse(
&mut reader,
parse_options.parsing_mode,
parse_options.read_properties,
)?;
Ok(Mp4File {
ftyp,