diff options
Diffstat (limited to 'third_party/rust/object/src/read/pe/resource.rs')
-rw-r--r-- | third_party/rust/object/src/read/pe/resource.rs | 207 |
1 files changed, 207 insertions, 0 deletions
diff --git a/third_party/rust/object/src/read/pe/resource.rs b/third_party/rust/object/src/read/pe/resource.rs new file mode 100644 index 0000000000..646eaefaaa --- /dev/null +++ b/third_party/rust/object/src/read/pe/resource.rs @@ -0,0 +1,207 @@ +use alloc::string::String; +use core::char; + +use crate::read::{ReadError, ReadRef, Result}; +use crate::{pe, LittleEndian as LE, U16Bytes}; + +/// The `.rsrc` section of a PE file. +#[derive(Debug, Clone, Copy)] +pub struct ResourceDirectory<'data> { + data: &'data [u8], +} + +impl<'data> ResourceDirectory<'data> { + /// Construct from the data of the `.rsrc` section. + pub fn new(data: &'data [u8]) -> Self { + ResourceDirectory { data } + } + + /// Parses the root resource directory. + pub fn root(&self) -> Result<ResourceDirectoryTable<'data>> { + ResourceDirectoryTable::parse(self.data, 0) + } +} + +/// A table of resource entries. +#[derive(Debug, Clone)] +pub struct ResourceDirectoryTable<'data> { + /// The table header. + pub header: &'data pe::ImageResourceDirectory, + /// The table entries. + pub entries: &'data [pe::ImageResourceDirectoryEntry], +} + +impl<'data> ResourceDirectoryTable<'data> { + fn parse(data: &'data [u8], offset: u32) -> Result<Self> { + let mut offset = u64::from(offset); + let header = data + .read::<pe::ImageResourceDirectory>(&mut offset) + .read_error("Invalid resource table header")?; + let entries_count = header.number_of_id_entries.get(LE) as usize + + header.number_of_named_entries.get(LE) as usize; + let entries = data + .read_slice::<pe::ImageResourceDirectoryEntry>(&mut offset, entries_count) + .read_error("Invalid resource table entries")?; + Ok(Self { header, entries }) + } +} + +impl pe::ImageResourceDirectoryEntry { + /// Returns true if the entry has a name, rather than an ID. + pub fn has_name(&self) -> bool { + self.name_or_id.get(LE) & pe::IMAGE_RESOURCE_NAME_IS_STRING != 0 + } + + /// Returns the section offset of the name. + /// + /// Valid if `has_name()` returns true. + fn name(&self) -> ResourceName { + let offset = self.name_or_id.get(LE) & !pe::IMAGE_RESOURCE_NAME_IS_STRING; + ResourceName { offset } + } + + /// Returns the ID. + /// + /// Valid if `has_string_name()` returns false. + fn id(&self) -> u16 { + (self.name_or_id.get(LE) & 0x0000_FFFF) as u16 + } + + /// Returns the entry name + pub fn name_or_id(&self) -> ResourceNameOrId { + if self.has_name() { + ResourceNameOrId::Name(self.name()) + } else { + ResourceNameOrId::Id(self.id()) + } + } + + /// Returns true if the entry is a subtable. + pub fn is_table(&self) -> bool { + self.offset_to_data_or_directory.get(LE) & pe::IMAGE_RESOURCE_DATA_IS_DIRECTORY != 0 + } + + /// Returns the section offset of the associated table or data. + pub fn data_offset(&self) -> u32 { + self.offset_to_data_or_directory.get(LE) & !pe::IMAGE_RESOURCE_DATA_IS_DIRECTORY + } + + /// Returns the data associated to this directory entry. + pub fn data<'data>( + &self, + section: ResourceDirectory<'data>, + ) -> Result<ResourceDirectoryEntryData<'data>> { + if self.is_table() { + ResourceDirectoryTable::parse(section.data, self.data_offset()) + .map(ResourceDirectoryEntryData::Table) + } else { + section + .data + .read_at::<pe::ImageResourceDataEntry>(self.data_offset().into()) + .read_error("Invalid resource entry") + .map(ResourceDirectoryEntryData::Data) + } + } +} + +/// Data associated with a resource directory entry. +#[derive(Debug, Clone)] +pub enum ResourceDirectoryEntryData<'data> { + /// A subtable entry. + Table(ResourceDirectoryTable<'data>), + /// A resource data entry. + Data(&'data pe::ImageResourceDataEntry), +} + +impl<'data> ResourceDirectoryEntryData<'data> { + /// Converts to an option of table. + /// + /// Helper for iterator filtering. + pub fn table(self) -> Option<ResourceDirectoryTable<'data>> { + match self { + Self::Table(dir) => Some(dir), + _ => None, + } + } + + /// Converts to an option of data entry. + /// + /// Helper for iterator filtering. + pub fn data(self) -> Option<&'data pe::ImageResourceDataEntry> { + match self { + Self::Data(rsc) => Some(rsc), + _ => None, + } + } +} + +/// A resource name. +#[derive(Debug, Clone, Copy)] +pub struct ResourceName { + offset: u32, +} + +impl ResourceName { + /// Converts to a `String`. + pub fn to_string_lossy(&self, directory: ResourceDirectory<'_>) -> Result<String> { + let d = self.data(directory)?.iter().map(|c| c.get(LE)); + + Ok(char::decode_utf16(d) + .map(|r| r.unwrap_or(char::REPLACEMENT_CHARACTER)) + .collect::<String>()) + } + + /// Returns the string unicode buffer. + pub fn data<'data>( + &self, + directory: ResourceDirectory<'data>, + ) -> Result<&'data [U16Bytes<LE>]> { + let mut offset = u64::from(self.offset); + let len = directory + .data + .read::<U16Bytes<LE>>(&mut offset) + .read_error("Invalid resource name offset")?; + directory + .data + .read_slice::<U16Bytes<LE>>(&mut offset, len.get(LE).into()) + .read_error("Invalid resource name length") + } + + /// Returns the string buffer as raw bytes. + pub fn raw_data<'data>(&self, directory: ResourceDirectory<'data>) -> Result<&'data [u8]> { + self.data(directory).map(crate::pod::bytes_of_slice) + } +} + +/// A resource name or ID. +/// +/// Can be either a string or a numeric ID. +#[derive(Debug)] +pub enum ResourceNameOrId { + /// A resource name. + Name(ResourceName), + /// A resource ID. + Id(u16), +} + +impl ResourceNameOrId { + /// Converts to an option of name. + /// + /// Helper for iterator filtering. + pub fn name(self) -> Option<ResourceName> { + match self { + Self::Name(name) => Some(name), + _ => None, + } + } + + /// Converts to an option of ID. + /// + /// Helper for iterator filtering. + pub fn id(self) -> Option<u16> { + match self { + Self::Id(id) => Some(id), + _ => None, + } + } +} |