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-rw-r--r--vendor/image/src/codecs/ico/decoder.rs470
1 files changed, 470 insertions, 0 deletions
diff --git a/vendor/image/src/codecs/ico/decoder.rs b/vendor/image/src/codecs/ico/decoder.rs
new file mode 100644
index 0000000..4f02787
--- /dev/null
+++ b/vendor/image/src/codecs/ico/decoder.rs
@@ -0,0 +1,470 @@
+use byteorder::{LittleEndian, ReadBytesExt};
+use std::convert::TryFrom;
+use std::io::{self, Cursor, Read, Seek, SeekFrom};
+use std::marker::PhantomData;
+use std::{error, fmt, mem};
+
+use crate::color::ColorType;
+use crate::error::{
+ DecodingError, ImageError, ImageResult, UnsupportedError, UnsupportedErrorKind,
+};
+use crate::image::{self, ImageDecoder, ImageFormat};
+
+use self::InnerDecoder::*;
+use crate::codecs::bmp::BmpDecoder;
+use crate::codecs::png::{PngDecoder, PNG_SIGNATURE};
+
+/// Errors that can occur during decoding and parsing an ICO image or one of its enclosed images.
+#[derive(Debug, Copy, Clone, Hash, PartialEq, Eq, PartialOrd, Ord)]
+enum DecoderError {
+ /// The ICO directory is empty
+ NoEntries,
+ /// The number of color planes (0 or 1), or the horizontal coordinate of the hotspot for CUR files too big.
+ IcoEntryTooManyPlanesOrHotspot,
+ /// The bit depth (may be 0 meaning unspecified), or the vertical coordinate of the hotspot for CUR files too big.
+ IcoEntryTooManyBitsPerPixelOrHotspot,
+
+ /// The entry is in PNG format and specified a length that is shorter than PNG header.
+ PngShorterThanHeader,
+ /// The enclosed PNG is not in RGBA, which is invalid: https://blogs.msdn.microsoft.com/oldnewthing/20101022-00/?p=12473/.
+ PngNotRgba,
+
+ /// The entry is in BMP format and specified a data size that is not correct for the image and optional mask data.
+ InvalidDataSize,
+
+ /// The dimensions specified by the entry does not match the dimensions in the header of the enclosed image.
+ ImageEntryDimensionMismatch {
+ /// The mismatched subimage's type
+ format: IcoEntryImageFormat,
+ /// The dimensions specified by the entry
+ entry: (u16, u16),
+ /// The dimensions of the image itself
+ image: (u32, u32),
+ },
+}
+
+impl fmt::Display for DecoderError {
+ fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+ match self {
+ DecoderError::NoEntries => f.write_str("ICO directory contains no image"),
+ DecoderError::IcoEntryTooManyPlanesOrHotspot => {
+ f.write_str("ICO image entry has too many color planes or too large hotspot value")
+ }
+ DecoderError::IcoEntryTooManyBitsPerPixelOrHotspot => f.write_str(
+ "ICO image entry has too many bits per pixel or too large hotspot value",
+ ),
+ DecoderError::PngShorterThanHeader => {
+ f.write_str("Entry specified a length that is shorter than PNG header!")
+ }
+ DecoderError::PngNotRgba => f.write_str("The PNG is not in RGBA format!"),
+ DecoderError::InvalidDataSize => {
+ f.write_str("ICO image data size did not match expected size")
+ }
+ DecoderError::ImageEntryDimensionMismatch {
+ format,
+ entry,
+ image,
+ } => f.write_fmt(format_args!(
+ "Entry{:?} and {}{:?} dimensions do not match!",
+ entry, format, image
+ )),
+ }
+ }
+}
+
+impl From<DecoderError> for ImageError {
+ fn from(e: DecoderError) -> ImageError {
+ ImageError::Decoding(DecodingError::new(ImageFormat::Ico.into(), e))
+ }
+}
+
+impl error::Error for DecoderError {}
+
+/// The image formats an ICO may contain
+#[derive(Debug, Copy, Clone, Hash, PartialEq, Eq, PartialOrd, Ord)]
+enum IcoEntryImageFormat {
+ /// PNG in ARGB
+ Png,
+ /// BMP with optional alpha mask
+ Bmp,
+}
+
+impl fmt::Display for IcoEntryImageFormat {
+ fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+ f.write_str(match self {
+ IcoEntryImageFormat::Png => "PNG",
+ IcoEntryImageFormat::Bmp => "BMP",
+ })
+ }
+}
+
+impl From<IcoEntryImageFormat> for ImageFormat {
+ fn from(val: IcoEntryImageFormat) -> Self {
+ match val {
+ IcoEntryImageFormat::Png => ImageFormat::Png,
+ IcoEntryImageFormat::Bmp => ImageFormat::Bmp,
+ }
+ }
+}
+
+/// An ico decoder
+pub struct IcoDecoder<R: Read> {
+ selected_entry: DirEntry,
+ inner_decoder: InnerDecoder<R>,
+}
+
+enum InnerDecoder<R: Read> {
+ Bmp(BmpDecoder<R>),
+ Png(Box<PngDecoder<R>>),
+}
+
+#[derive(Clone, Copy, Default)]
+struct DirEntry {
+ width: u8,
+ height: u8,
+ // We ignore some header fields as they will be replicated in the PNG, BMP and they are not
+ // necessary for determining the best_entry.
+ #[allow(unused)]
+ color_count: u8,
+ // Wikipedia has this to say:
+ // Although Microsoft's technical documentation states that this value must be zero, the icon
+ // encoder built into .NET (System.Drawing.Icon.Save) sets this value to 255. It appears that
+ // the operating system ignores this value altogether.
+ #[allow(unused)]
+ reserved: u8,
+
+ // We ignore some header fields as they will be replicated in the PNG, BMP and they are not
+ // necessary for determining the best_entry.
+ #[allow(unused)]
+ num_color_planes: u16,
+ bits_per_pixel: u16,
+
+ image_length: u32,
+ image_offset: u32,
+}
+
+impl<R: Read + Seek> IcoDecoder<R> {
+ /// Create a new decoder that decodes from the stream ```r```
+ pub fn new(mut r: R) -> ImageResult<IcoDecoder<R>> {
+ let entries = read_entries(&mut r)?;
+ let entry = best_entry(entries)?;
+ let decoder = entry.decoder(r)?;
+
+ Ok(IcoDecoder {
+ selected_entry: entry,
+ inner_decoder: decoder,
+ })
+ }
+}
+
+fn read_entries<R: Read>(r: &mut R) -> ImageResult<Vec<DirEntry>> {
+ let _reserved = r.read_u16::<LittleEndian>()?;
+ let _type = r.read_u16::<LittleEndian>()?;
+ let count = r.read_u16::<LittleEndian>()?;
+ (0..count).map(|_| read_entry(r)).collect()
+}
+
+fn read_entry<R: Read>(r: &mut R) -> ImageResult<DirEntry> {
+ Ok(DirEntry {
+ width: r.read_u8()?,
+ height: r.read_u8()?,
+ color_count: r.read_u8()?,
+ reserved: r.read_u8()?,
+ num_color_planes: {
+ // This may be either the number of color planes (0 or 1), or the horizontal coordinate
+ // of the hotspot for CUR files.
+ let num = r.read_u16::<LittleEndian>()?;
+ if num > 256 {
+ return Err(DecoderError::IcoEntryTooManyPlanesOrHotspot.into());
+ }
+ num
+ },
+ bits_per_pixel: {
+ // This may be either the bit depth (may be 0 meaning unspecified),
+ // or the vertical coordinate of the hotspot for CUR files.
+ let num = r.read_u16::<LittleEndian>()?;
+ if num > 256 {
+ return Err(DecoderError::IcoEntryTooManyBitsPerPixelOrHotspot.into());
+ }
+ num
+ },
+ image_length: r.read_u32::<LittleEndian>()?,
+ image_offset: r.read_u32::<LittleEndian>()?,
+ })
+}
+
+/// Find the entry with the highest (color depth, size).
+fn best_entry(mut entries: Vec<DirEntry>) -> ImageResult<DirEntry> {
+ let mut best = entries.pop().ok_or(DecoderError::NoEntries)?;
+
+ let mut best_score = (
+ best.bits_per_pixel,
+ u32::from(best.real_width()) * u32::from(best.real_height()),
+ );
+
+ for entry in entries {
+ let score = (
+ entry.bits_per_pixel,
+ u32::from(entry.real_width()) * u32::from(entry.real_height()),
+ );
+ if score > best_score {
+ best = entry;
+ best_score = score;
+ }
+ }
+ Ok(best)
+}
+
+impl DirEntry {
+ fn real_width(&self) -> u16 {
+ match self.width {
+ 0 => 256,
+ w => u16::from(w),
+ }
+ }
+
+ fn real_height(&self) -> u16 {
+ match self.height {
+ 0 => 256,
+ h => u16::from(h),
+ }
+ }
+
+ fn matches_dimensions(&self, width: u32, height: u32) -> bool {
+ u32::from(self.real_width()) == width.min(256)
+ && u32::from(self.real_height()) == height.min(256)
+ }
+
+ fn seek_to_start<R: Read + Seek>(&self, r: &mut R) -> ImageResult<()> {
+ r.seek(SeekFrom::Start(u64::from(self.image_offset)))?;
+ Ok(())
+ }
+
+ fn is_png<R: Read + Seek>(&self, r: &mut R) -> ImageResult<bool> {
+ self.seek_to_start(r)?;
+
+ // Read the first 8 bytes to sniff the image.
+ let mut signature = [0u8; 8];
+ r.read_exact(&mut signature)?;
+
+ Ok(signature == PNG_SIGNATURE)
+ }
+
+ fn decoder<R: Read + Seek>(&self, mut r: R) -> ImageResult<InnerDecoder<R>> {
+ let is_png = self.is_png(&mut r)?;
+ self.seek_to_start(&mut r)?;
+
+ if is_png {
+ Ok(Png(Box::new(PngDecoder::new(r)?)))
+ } else {
+ Ok(Bmp(BmpDecoder::new_with_ico_format(r)?))
+ }
+ }
+}
+
+/// Wrapper struct around a `Cursor<Vec<u8>>`
+pub struct IcoReader<R>(Cursor<Vec<u8>>, PhantomData<R>);
+impl<R> Read for IcoReader<R> {
+ fn read(&mut self, buf: &mut [u8]) -> io::Result<usize> {
+ self.0.read(buf)
+ }
+ fn read_to_end(&mut self, buf: &mut Vec<u8>) -> io::Result<usize> {
+ if self.0.position() == 0 && buf.is_empty() {
+ mem::swap(buf, self.0.get_mut());
+ Ok(buf.len())
+ } else {
+ self.0.read_to_end(buf)
+ }
+ }
+}
+
+impl<'a, R: 'a + Read + Seek> ImageDecoder<'a> for IcoDecoder<R> {
+ type Reader = IcoReader<R>;
+
+ fn dimensions(&self) -> (u32, u32) {
+ match self.inner_decoder {
+ Bmp(ref decoder) => decoder.dimensions(),
+ Png(ref decoder) => decoder.dimensions(),
+ }
+ }
+
+ fn color_type(&self) -> ColorType {
+ match self.inner_decoder {
+ Bmp(ref decoder) => decoder.color_type(),
+ Png(ref decoder) => decoder.color_type(),
+ }
+ }
+
+ fn into_reader(self) -> ImageResult<Self::Reader> {
+ Ok(IcoReader(
+ Cursor::new(image::decoder_to_vec(self)?),
+ PhantomData,
+ ))
+ }
+
+ fn read_image(self, buf: &mut [u8]) -> ImageResult<()> {
+ assert_eq!(u64::try_from(buf.len()), Ok(self.total_bytes()));
+ match self.inner_decoder {
+ Png(decoder) => {
+ if self.selected_entry.image_length < PNG_SIGNATURE.len() as u32 {
+ return Err(DecoderError::PngShorterThanHeader.into());
+ }
+
+ // Check if the image dimensions match the ones in the image data.
+ let (width, height) = decoder.dimensions();
+ if !self.selected_entry.matches_dimensions(width, height) {
+ return Err(DecoderError::ImageEntryDimensionMismatch {
+ format: IcoEntryImageFormat::Png,
+ entry: (
+ self.selected_entry.real_width(),
+ self.selected_entry.real_height(),
+ ),
+ image: (width, height),
+ }
+ .into());
+ }
+
+ // Embedded PNG images can only be of the 32BPP RGBA format.
+ // https://blogs.msdn.microsoft.com/oldnewthing/20101022-00/?p=12473/
+ if decoder.color_type() != ColorType::Rgba8 {
+ return Err(DecoderError::PngNotRgba.into());
+ }
+
+ decoder.read_image(buf)
+ }
+ Bmp(mut decoder) => {
+ let (width, height) = decoder.dimensions();
+ if !self.selected_entry.matches_dimensions(width, height) {
+ return Err(DecoderError::ImageEntryDimensionMismatch {
+ format: IcoEntryImageFormat::Bmp,
+ entry: (
+ self.selected_entry.real_width(),
+ self.selected_entry.real_height(),
+ ),
+ image: (width, height),
+ }
+ .into());
+ }
+
+ // The ICO decoder needs an alpha channel to apply the AND mask.
+ if decoder.color_type() != ColorType::Rgba8 {
+ return Err(ImageError::Unsupported(
+ UnsupportedError::from_format_and_kind(
+ ImageFormat::Bmp.into(),
+ UnsupportedErrorKind::Color(decoder.color_type().into()),
+ ),
+ ));
+ }
+
+ decoder.read_image_data(buf)?;
+
+ let r = decoder.reader();
+ let image_end = r.stream_position()?;
+ let data_end = u64::from(self.selected_entry.image_offset)
+ + u64::from(self.selected_entry.image_length);
+
+ let mask_row_bytes = ((width + 31) / 32) * 4;
+ let mask_length = u64::from(mask_row_bytes) * u64::from(height);
+
+ // data_end should be image_end + the mask length (mask_row_bytes * height).
+ // According to
+ // https://devblogs.microsoft.com/oldnewthing/20101021-00/?p=12483
+ // the mask is required, but according to Wikipedia
+ // https://en.wikipedia.org/wiki/ICO_(file_format)
+ // the mask is not required. Unfortunately, Wikipedia does not have a citation
+ // for that claim, so we can't be sure which is correct.
+ if data_end >= image_end + mask_length {
+ // If there's an AND mask following the image, read and apply it.
+ for y in 0..height {
+ let mut x = 0;
+ for _ in 0..mask_row_bytes {
+ // Apply the bits of each byte until we reach the end of the row.
+ let mask_byte = r.read_u8()?;
+ for bit in (0..8).rev() {
+ if x >= width {
+ break;
+ }
+ if mask_byte & (1 << bit) != 0 {
+ // Set alpha channel to transparent.
+ buf[((height - y - 1) * width + x) as usize * 4 + 3] = 0;
+ }
+ x += 1;
+ }
+ }
+ }
+
+ Ok(())
+ } else if data_end == image_end {
+ // accept images with no mask data
+ Ok(())
+ } else {
+ Err(DecoderError::InvalidDataSize.into())
+ }
+ }
+ }
+ }
+}
+
+#[cfg(test)]
+mod test {
+ use super::*;
+
+ // Test if BMP images without alpha channel inside ICOs don't panic.
+ // Because the test data is invalid decoding should produce an error.
+ #[test]
+ fn bmp_16_with_missing_alpha_channel() {
+ let data = vec![
+ 0x00, 0x00, 0x01, 0x00, 0x01, 0x00, 0x0e, 0x04, 0xc3, 0x7e, 0x00, 0x00, 0x00, 0x00,
+ 0x7c, 0x00, 0x00, 0x00, 0x0e, 0x00, 0x00, 0x00, 0xf8, 0xff, 0xff, 0xff, 0x01, 0x00,
+ 0x10, 0x00, 0x00, 0x00, 0x00, 0x00, 0x12, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+ 0x00, 0x00, 0x00, 0x8f, 0xf6, 0xff, 0xff, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+ 0x20, 0x66, 0x74, 0x83, 0x70, 0x61, 0x76, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02,
+ 0x00, 0x00, 0x00, 0x00, 0xff, 0xff, 0xff, 0xeb, 0x00, 0x9b, 0x00, 0x00, 0x00, 0x00,
+ 0x00, 0x00, 0x00, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x4e, 0x47, 0x0d,
+ 0x0a, 0x1a, 0x0a, 0x00, 0x00, 0x00, 0x62, 0x49, 0x48, 0x44, 0x52, 0x00, 0x00, 0x00,
+ 0x00, 0x00, 0x00, 0x00, 0x00, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02, 0x0c,
+ 0x00, 0x00, 0x00, 0xc3, 0x3f, 0x94, 0x61, 0xaa, 0x17, 0x4d, 0x8d, 0x79, 0x1d, 0x8b,
+ 0x10, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x14, 0x2e, 0x28, 0x40, 0xe5, 0x9f,
+ 0x4b, 0x4d, 0xe9, 0x87, 0xd3, 0xda, 0xd6, 0x89, 0x81, 0xc5, 0xa4, 0xa1, 0x60, 0x98,
+ 0x31, 0xc7, 0x1d, 0xb6, 0x8f, 0x20, 0xc8, 0x3e, 0xee, 0xd8, 0xe4, 0x8f, 0xee, 0x7b,
+ 0x48, 0x9b, 0x88, 0x25, 0x13, 0xda, 0xa4, 0x13, 0xa4, 0x00, 0x00, 0x00, 0x00, 0x40,
+ 0x16, 0x01, 0xff, 0xff, 0xff, 0xff, 0xe9, 0x0c, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+ 0x00, 0x00, 0xa3, 0x66, 0x64, 0x41, 0x54, 0xa3, 0xa3, 0x00, 0x00, 0x00, 0xb8, 0x00,
+ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xa3, 0x66, 0x64, 0x41, 0x54, 0xa3, 0xa3,
+ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x8f, 0xf6, 0xff, 0xff,
+ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x20, 0x66, 0x74, 0x83, 0x70, 0x61, 0x76,
+ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02, 0x00, 0x00, 0x00, 0x00, 0xff, 0xff, 0xff,
+ 0xeb, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x08, 0x00, 0x00, 0x00, 0x00,
+ 0x00, 0x00, 0x00, 0x4e, 0x47, 0x0d, 0x0a, 0x1a, 0x0a, 0x00, 0x00, 0x00, 0x62, 0x49,
+ 0x48, 0x44, 0x52, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x08, 0x00, 0x00,
+ 0x00, 0x00, 0x00, 0xff, 0xff, 0x94, 0xc8, 0x00, 0x02, 0x0c, 0x00, 0xff, 0xff, 0xc6,
+ 0x84, 0x00, 0x2a, 0x75, 0x03, 0xa3, 0x05, 0xfb, 0xe1, 0x6e, 0xe8, 0x27, 0xd6, 0xd3,
+ 0x96, 0xc1, 0xe4, 0x30, 0x0c, 0x05, 0xb9, 0xa3, 0x8b, 0x29, 0xda, 0xa4, 0xf1, 0x4d,
+ 0xf3, 0xb2, 0x98, 0x2b, 0xe6, 0x93, 0x07, 0xf9, 0xca, 0x2b, 0xc2, 0x39, 0x20, 0xba,
+ 0x7c, 0xa0, 0xb1, 0x43, 0xe6, 0xf9, 0xdc, 0xd1, 0xc2, 0x52, 0xdc, 0x41, 0xc1, 0x2f,
+ 0x29, 0xf7, 0x46, 0x32, 0xda, 0x1b, 0x72, 0x8c, 0xe6, 0x2b, 0x01, 0xe5, 0x49, 0x21,
+ 0x89, 0x89, 0xe4, 0x3d, 0xa1, 0xdb, 0x3b, 0x4a, 0x0b, 0x52, 0x86, 0x52, 0x33, 0x9d,
+ 0xb2, 0xcf, 0x4a, 0x86, 0x53, 0xd7, 0xa9, 0x4b, 0xaf, 0x62, 0x06, 0x49, 0x53, 0x00,
+ 0xc3, 0x3f, 0x94, 0x61, 0xaa, 0x17, 0x4d, 0x8d, 0x79, 0x1d, 0x8b, 0x10, 0x00, 0x00,
+ 0x00, 0x00, 0x00, 0x00, 0x00, 0x14, 0x2e, 0x28, 0x40, 0xe5, 0x9f, 0x4b, 0x4d, 0xe9,
+ 0x87, 0xd3, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xe7, 0xc5, 0x00,
+ 0x02, 0x00, 0x00, 0x00, 0x06, 0x00, 0x0b, 0x00, 0x50, 0x31, 0x00, 0x00, 0x00, 0x00,
+ 0x00, 0x00, 0x00, 0x00, 0x00, 0x06, 0x76, 0x76, 0x01, 0x00, 0x00, 0x00, 0x76, 0x00,
+ 0x00, 0x23, 0x3f, 0x52, 0x41, 0x44, 0x49, 0x41, 0x4e, 0x43, 0x45, 0x61, 0x50, 0x35,
+ 0x00, 0x00, 0x00, 0x00, 0x00, 0x03, 0x4d, 0x47, 0x49, 0x46, 0x38, 0x37, 0x61, 0x05,
+ 0x50, 0x37, 0x00, 0x00, 0x00, 0x00, 0x00, 0xc7, 0x37, 0x61,
+ ];
+
+ let decoder = IcoDecoder::new(Cursor::new(&data)).unwrap();
+ let mut buf = vec![0; usize::try_from(decoder.total_bytes()).unwrap()];
+ assert!(decoder.read_image(&mut buf).is_err());
+ }
+}
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