diff options
Diffstat (limited to 'vendor/object-0.26.2/src/read/macho/dyld_cache.rs')
-rw-r--r-- | vendor/object-0.26.2/src/read/macho/dyld_cache.rs | 218 |
1 files changed, 218 insertions, 0 deletions
diff --git a/vendor/object-0.26.2/src/read/macho/dyld_cache.rs b/vendor/object-0.26.2/src/read/macho/dyld_cache.rs new file mode 100644 index 000000000..ee758ce0c --- /dev/null +++ b/vendor/object-0.26.2/src/read/macho/dyld_cache.rs @@ -0,0 +1,218 @@ +use core::slice; + +use crate::read::{Error, File, ReadError, ReadRef, Result}; +use crate::{macho, Architecture, Endian, Endianness}; + +/// A parsed representation of the dyld shared cache. +#[derive(Debug)] +pub struct DyldCache<'data, E = Endianness, R = &'data [u8]> +where + E: Endian, + R: ReadRef<'data>, +{ + endian: E, + data: R, + header: &'data macho::DyldCacheHeader<E>, + mappings: &'data [macho::DyldCacheMappingInfo<E>], + images: &'data [macho::DyldCacheImageInfo<E>], + arch: Architecture, +} + +impl<'data, E, R> DyldCache<'data, E, R> +where + E: Endian, + R: ReadRef<'data>, +{ + /// Parse the raw dyld shared cache data. + pub fn parse(data: R) -> Result<Self> { + let header = macho::DyldCacheHeader::parse(data)?; + let (arch, endian) = header.parse_magic()?; + let mappings = header.mappings(endian, data)?; + let images = header.images(endian, data)?; + Ok(DyldCache { + endian, + data, + header, + mappings, + images, + arch, + }) + } + + /// Get the architecture type of the file. + pub fn architecture(&self) -> Architecture { + self.arch + } + + /// Get the endianness of the file. + #[inline] + pub fn endianness(&self) -> Endianness { + if self.is_little_endian() { + Endianness::Little + } else { + Endianness::Big + } + } + + /// Return true if the file is little endian, false if it is big endian. + pub fn is_little_endian(&self) -> bool { + self.endian.is_little_endian() + } + + /// Iterate over the images in this cache. + pub fn images<'cache>(&'cache self) -> DyldCacheImageIterator<'data, 'cache, E, R> { + DyldCacheImageIterator { + cache: self, + iter: self.images.iter(), + } + } +} + +/// An iterator over all the images (dylibs) in the dyld shared cache. +#[derive(Debug)] +pub struct DyldCacheImageIterator<'data, 'cache, E = Endianness, R = &'data [u8]> +where + E: Endian, + R: ReadRef<'data>, +{ + cache: &'cache DyldCache<'data, E, R>, + iter: slice::Iter<'data, macho::DyldCacheImageInfo<E>>, +} + +impl<'data, 'cache, E, R> Iterator for DyldCacheImageIterator<'data, 'cache, E, R> +where + E: Endian, + R: ReadRef<'data>, +{ + type Item = DyldCacheImage<'data, E, R>; + + fn next(&mut self) -> Option<DyldCacheImage<'data, E, R>> { + let image_info = self.iter.next()?; + Some(DyldCacheImage { + endian: self.cache.endian, + data: self.cache.data, + mappings: self.cache.mappings, + image_info, + }) + } +} + +/// One image (dylib) from inside the dyld shared cache. +#[derive(Debug)] +pub struct DyldCacheImage<'data, E = Endianness, R = &'data [u8]> +where + E: Endian, + R: ReadRef<'data>, +{ + endian: E, + data: R, + mappings: &'data [macho::DyldCacheMappingInfo<E>], + image_info: &'data macho::DyldCacheImageInfo<E>, +} + +impl<'data, E, R> DyldCacheImage<'data, E, R> +where + E: Endian, + R: ReadRef<'data>, +{ + /// The file system path of this image. + pub fn path(&self) -> Result<&'data str> { + let path = self.image_info.path(self.endian, self.data)?; + // The path should always be ascii, so from_utf8 should alway succeed. + let path = core::str::from_utf8(path).map_err(|_| Error("Path string not valid utf-8"))?; + Ok(path) + } + + /// The offset in the dyld cache file where this image starts. + pub fn file_offset(&self) -> Result<u64> { + self.image_info.file_offset(self.endian, self.mappings) + } + + /// Parse this image into an Object. + pub fn parse_object(&self) -> Result<File<'data, R>> { + File::parse_at(self.data, self.file_offset()?) + } +} + +impl<E: Endian> macho::DyldCacheHeader<E> { + /// Read the dyld cache header. + pub fn parse<'data, R: ReadRef<'data>>(data: R) -> Result<&'data Self> { + data.read_at::<macho::DyldCacheHeader<E>>(0) + .read_error("Invalid dyld cache header size or alignment") + } + + /// Returns (arch, endian) based on the magic string. + pub fn parse_magic(&self) -> Result<(Architecture, E)> { + let (arch, is_big_endian) = match &self.magic { + b"dyld_v1 i386\0" => (Architecture::I386, false), + b"dyld_v1 x86_64\0" => (Architecture::X86_64, false), + b"dyld_v1 x86_64h\0" => (Architecture::X86_64, false), + b"dyld_v1 ppc\0" => (Architecture::PowerPc, true), + b"dyld_v1 armv6\0" => (Architecture::Arm, false), + b"dyld_v1 armv7\0" => (Architecture::Arm, false), + b"dyld_v1 armv7f\0" => (Architecture::Arm, false), + b"dyld_v1 armv7s\0" => (Architecture::Arm, false), + b"dyld_v1 armv7k\0" => (Architecture::Arm, false), + b"dyld_v1 arm64\0" => (Architecture::Aarch64, false), + b"dyld_v1 arm64e\0" => (Architecture::Aarch64, false), + _ => return Err(Error("Unrecognized dyld cache magic")), + }; + let endian = + E::from_big_endian(is_big_endian).read_error("Unsupported dyld cache endian")?; + Ok((arch, endian)) + } + + /// Return the mapping information table. + pub fn mappings<'data, R: ReadRef<'data>>( + &self, + endian: E, + data: R, + ) -> Result<&'data [macho::DyldCacheMappingInfo<E>]> { + data.read_slice_at::<macho::DyldCacheMappingInfo<E>>( + self.mapping_offset.get(endian).into(), + self.mapping_count.get(endian) as usize, + ) + .read_error("Invalid dyld cache mapping size or alignment") + } + + /// Return the image information table. + pub fn images<'data, R: ReadRef<'data>>( + &self, + endian: E, + data: R, + ) -> Result<&'data [macho::DyldCacheImageInfo<E>]> { + data.read_slice_at::<macho::DyldCacheImageInfo<E>>( + self.images_offset.get(endian).into(), + self.images_count.get(endian) as usize, + ) + .read_error("Invalid dyld cache image size or alignment") + } +} + +impl<E: Endian> macho::DyldCacheImageInfo<E> { + /// The file system path of this image. + pub fn path<'data, R: ReadRef<'data>>(&self, endian: E, data: R) -> Result<&'data [u8]> { + let r_start = self.path_file_offset.get(endian).into(); + let r_end = data.len().read_error("Couldn't get data len()")?; + data.read_bytes_at_until(r_start..r_end, 0) + .read_error("Couldn't read dyld cache image path") + } + + /// Find the file offset of the image by looking up its address in the mappings. + pub fn file_offset( + &self, + endian: E, + mappings: &[macho::DyldCacheMappingInfo<E>], + ) -> Result<u64> { + let address = self.address.get(endian); + for mapping in mappings { + let mapping_address = mapping.address.get(endian); + if address >= mapping_address + && address < mapping_address.wrapping_add(mapping.size.get(endian)) + { + return Ok(address - mapping_address + mapping.file_offset.get(endian)); + } + } + Err(Error("Invalid dyld cache image address")) + } +} |