Initial vendor packages

Signed-off-by: Valentin Popov <valentin@popov.link>

1 files changed, 344 insertions, 0 deletions

diff --git a/vendor/object/src/read/macho/dyld_cache.rs b/vendor/object/src/read/macho/dyld_cache.rs
new file mode 100644
index 0000000..0f5dfc5
--- /dev/null
+++ b/vendor/object/src/read/macho/dyld_cache.rs
@@ -0,0 +1,344 @@
+use alloc::vec::Vec;
+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,
+    subcaches: Vec<DyldSubCache<'data, E, R>>,
+    mappings: &'data [macho::DyldCacheMappingInfo<E>],
+    images: &'data [macho::DyldCacheImageInfo<E>],
+    arch: Architecture,
+}
+
+/// Information about a subcache.
+#[derive(Debug)]
+pub struct DyldSubCache<'data, E = Endianness, R = &'data [u8]>
+where
+    E: Endian,
+    R: ReadRef<'data>,
+{
+    data: R,
+    mappings: &'data [macho::DyldCacheMappingInfo<E>],
+}
+
+// This is the offset of the images_across_all_subcaches_count field.
+const MIN_HEADER_SIZE_SUBCACHES: u32 = 0x1c4;
+
+impl<'data, E, R> DyldCache<'data, E, R>
+where
+    E: Endian,
+    R: ReadRef<'data>,
+{
+    /// Parse the raw dyld shared cache data.
+    ///
+    /// For shared caches from macOS 12 / iOS 15 and above, the subcache files need to be
+    /// supplied as well, in the correct order, with the `.symbols` subcache last (if present).
+    /// For example, `data` would be the data for `dyld_shared_cache_x86_64`,
+    /// and `subcache_data` would be the data for `[dyld_shared_cache_x86_64.1, dyld_shared_cache_x86_64.2, ...]`.
+    pub fn parse(data: R, subcache_data: &[R]) -> Result<Self> {
+        let header = macho::DyldCacheHeader::parse(data)?;
+        let (arch, endian) = header.parse_magic()?;
+        let mappings = header.mappings(endian, data)?;
+
+        let symbols_subcache_uuid = header.symbols_subcache_uuid(endian);
+        let subcaches_info = header.subcaches(endian, data)?.unwrap_or(&[]);
+
+        if subcache_data.len() != subcaches_info.len() + symbols_subcache_uuid.is_some() as usize {
+            return Err(Error("Incorrect number of SubCaches"));
+        }
+
+        // Split out the .symbols subcache data from the other subcaches.
+        let (symbols_subcache_data_and_uuid, subcache_data) =
+            if let Some(symbols_uuid) = symbols_subcache_uuid {
+                let (sym_data, rest_data) = subcache_data.split_last().unwrap();
+                (Some((*sym_data, symbols_uuid)), rest_data)
+            } else {
+                (None, subcache_data)
+            };
+
+        // Read the regular SubCaches (.1, .2, ...), if present.
+        let mut subcaches = Vec::new();
+        for (&data, info) in subcache_data.iter().zip(subcaches_info.iter()) {
+            let sc_header = macho::DyldCacheHeader::<E>::parse(data)?;
+            if sc_header.uuid != info.uuid {
+                return Err(Error("Unexpected SubCache UUID"));
+            }
+            let mappings = sc_header.mappings(endian, data)?;
+            subcaches.push(DyldSubCache { data, mappings });
+        }
+
+        // Read the .symbols SubCache, if present.
+        // Other than the UUID verification, the symbols SubCache is currently unused.
+        let _symbols_subcache = match symbols_subcache_data_and_uuid {
+            Some((data, uuid)) => {
+                let sc_header = macho::DyldCacheHeader::<E>::parse(data)?;
+                if sc_header.uuid != uuid {
+                    return Err(Error("Unexpected .symbols SubCache UUID"));
+                }
+                let mappings = sc_header.mappings(endian, data)?;
+                Some(DyldSubCache { data, mappings })
+            }
+            None => None,
+        };
+
+        let images = header.images(endian, data)?;
+        Ok(DyldCache {
+            endian,
+            data,
+            subcaches,
+            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(),
+        }
+    }
+
+    /// Find the address in a mapping and return the cache or subcache data it was found in,
+    /// together with the translated file offset.
+    pub fn data_and_offset_for_address(&self, address: u64) -> Option<(R, u64)> {
+        if let Some(file_offset) = address_to_file_offset(address, self.endian, self.mappings) {
+            return Some((self.data, file_offset));
+        }
+        for subcache in &self.subcaches {
+            if let Some(file_offset) =
+                address_to_file_offset(address, self.endian, subcache.mappings)
+            {
+                return Some((subcache.data, file_offset));
+            }
+        }
+        None
+    }
+}
+
+/// 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, 'cache, E, R>;
+
+    fn next(&mut self) -> Option<DyldCacheImage<'data, 'cache, E, R>> {
+        let image_info = self.iter.next()?;
+        Some(DyldCacheImage {
+            cache: self.cache,
+            image_info,
+        })
+    }
+}
+
+/// One image (dylib) from inside the dyld shared cache.
+#[derive(Debug)]
+pub struct DyldCacheImage<'data, 'cache, E = Endianness, R = &'data [u8]>
+where
+    E: Endian,
+    R: ReadRef<'data>,
+{
+    pub(crate) cache: &'cache DyldCache<'data, E, R>,
+    image_info: &'data macho::DyldCacheImageInfo<E>,
+}
+
+impl<'data, 'cache, E, R> DyldCacheImage<'data, 'cache, 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.cache.endian, self.cache.data)?;
+        // The path should always be ascii, so from_utf8 should always succeed.
+        let path = core::str::from_utf8(path).map_err(|_| Error("Path string not valid utf-8"))?;
+        Ok(path)
+    }
+
+    /// The subcache data which contains the Mach-O header for this image,
+    /// together with the file offset at which this image starts.
+    pub fn image_data_and_offset(&self) -> Result<(R, u64)> {
+        let address = self.image_info.address.get(self.cache.endian);
+        self.cache
+            .data_and_offset_for_address(address)
+            .ok_or(Error("Address not found in any mapping"))
+    }
+
+    /// Parse this image into an Object.
+    pub fn parse_object(&self) -> Result<File<'data, R>> {
+        File::parse_dyld_cache_image(self)
+    }
+}
+
+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 information about subcaches, if present.
+    pub fn subcaches<'data, R: ReadRef<'data>>(
+        &self,
+        endian: E,
+        data: R,
+    ) -> Result<Option<&'data [macho::DyldSubCacheInfo<E>]>> {
+        if self.mapping_offset.get(endian) >= MIN_HEADER_SIZE_SUBCACHES {
+            let subcaches = data
+                .read_slice_at::<macho::DyldSubCacheInfo<E>>(
+                    self.subcaches_offset.get(endian).into(),
+                    self.subcaches_count.get(endian) as usize,
+                )
+                .read_error("Invalid dyld subcaches size or alignment")?;
+            Ok(Some(subcaches))
+        } else {
+            Ok(None)
+        }
+    }
+
+    /// Return the UUID for the .symbols subcache, if present.
+    pub fn symbols_subcache_uuid(&self, endian: E) -> Option<[u8; 16]> {
+        if self.mapping_offset.get(endian) >= MIN_HEADER_SIZE_SUBCACHES {
+            let uuid = self.symbols_subcache_uuid;
+            if uuid != [0; 16] {
+                return Some(uuid);
+            }
+        }
+        None
+    }
+
+    /// Return the image information table.
+    pub fn images<'data, R: ReadRef<'data>>(
+        &self,
+        endian: E,
+        data: R,
+    ) -> Result<&'data [macho::DyldCacheImageInfo<E>]> {
+        if self.mapping_offset.get(endian) >= MIN_HEADER_SIZE_SUBCACHES {
+            data.read_slice_at::<macho::DyldCacheImageInfo<E>>(
+                self.images_across_all_subcaches_offset.get(endian).into(),
+                self.images_across_all_subcaches_count.get(endian) as usize,
+            )
+            .read_error("Invalid dyld cache image size or alignment")
+        } else {
+            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);
+        address_to_file_offset(address, endian, mappings)
+            .read_error("Invalid dyld cache image address")
+    }
+}
+
+/// Find the file offset of the image by looking up its address in the mappings.
+pub fn address_to_file_offset<E: Endian>(
+    address: u64,
+    endian: E,
+    mappings: &[macho::DyldCacheMappingInfo<E>],
+) -> Option<u64> {
+    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 Some(address - mapping_address + mapping.file_offset.get(endian));
+        }
+    }
+    None
+}