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Diffstat (limited to 'vendor/object/src/write/coff/writer.rs')
| -rw-r--r-- | vendor/object/src/write/coff/writer.rs | 518 |
1 files changed, 0 insertions, 518 deletions
diff --git a/vendor/object/src/write/coff/writer.rs b/vendor/object/src/write/coff/writer.rs deleted file mode 100644 index 8c7ada3..0000000 --- a/vendor/object/src/write/coff/writer.rs +++ /dev/null @@ -1,518 +0,0 @@ -//! Helper for writing COFF files. -use alloc::string::String; -use alloc::vec::Vec; -use core::mem; - -use crate::endian::{LittleEndian as LE, U16Bytes, U32Bytes, U16, U32}; -use crate::pe; -use crate::write::string::{StringId, StringTable}; -use crate::write::util; -use crate::write::{Error, Result, WritableBuffer}; - -/// A helper for writing COFF files. -/// -/// Writing uses a two phase approach. The first phase builds up all of the information -/// that may need to be known ahead of time: -/// - build string table -/// - reserve section indices -/// - reserve symbol indices -/// - reserve file ranges for headers and sections -/// -/// Some of the information has ordering requirements. For example, strings must be added -/// to the string table before reserving the file range for the string table. There are debug -/// asserts to check some of these requirements. -/// -/// The second phase writes everything out in order. Thus the caller must ensure writing -/// is in the same order that file ranges were reserved. There are debug asserts to assist -/// with checking this. -#[allow(missing_debug_implementations)] -pub struct Writer<'a> { - buffer: &'a mut dyn WritableBuffer, - len: usize, - - section_num: u16, - - symtab_offset: u32, - symtab_num: u32, - - strtab: StringTable<'a>, - strtab_len: usize, - strtab_offset: u32, - strtab_data: Vec<u8>, -} - -impl<'a> Writer<'a> { - /// Create a new `Writer`. - pub fn new(buffer: &'a mut dyn WritableBuffer) -> Self { - Writer { - buffer, - len: 0, - - section_num: 0, - - symtab_offset: 0, - symtab_num: 0, - - strtab: StringTable::default(), - strtab_len: 0, - strtab_offset: 0, - strtab_data: Vec::new(), - } - } - - /// Return the current file length that has been reserved. - pub fn reserved_len(&self) -> usize { - self.len - } - - /// Return the current file length that has been written. - #[allow(clippy::len_without_is_empty)] - pub fn len(&self) -> usize { - self.buffer.len() - } - - /// Reserve a file range with the given size and starting alignment. - /// - /// Returns the aligned offset of the start of the range. - pub fn reserve(&mut self, len: usize, align_start: usize) -> u32 { - if align_start > 1 { - self.len = util::align(self.len, align_start); - } - let offset = self.len; - self.len += len; - offset as u32 - } - - /// Write alignment padding bytes. - pub fn write_align(&mut self, align_start: usize) { - if align_start > 1 { - util::write_align(self.buffer, align_start); - } - } - - /// Write data. - pub fn write(&mut self, data: &[u8]) { - self.buffer.write_bytes(data); - } - - /// Reserve the file range up to the given file offset. - pub fn reserve_until(&mut self, offset: usize) { - debug_assert!(self.len <= offset); - self.len = offset; - } - - /// Write padding up to the given file offset. - pub fn pad_until(&mut self, offset: usize) { - debug_assert!(self.buffer.len() <= offset); - self.buffer.resize(offset); - } - - /// Reserve the range for the file header. - /// - /// This must be at the start of the file. - pub fn reserve_file_header(&mut self) { - debug_assert_eq!(self.len, 0); - self.reserve(mem::size_of::<pe::ImageFileHeader>(), 1); - } - - /// Write the file header. - /// - /// This must be at the start of the file. - /// - /// Fields that can be derived from known information are automatically set by this function. - pub fn write_file_header(&mut self, header: FileHeader) -> Result<()> { - debug_assert_eq!(self.buffer.len(), 0); - - // Start writing. - self.buffer - .reserve(self.len) - .map_err(|_| Error(String::from("Cannot allocate buffer")))?; - - // Write file header. - let header = pe::ImageFileHeader { - machine: U16::new(LE, header.machine), - number_of_sections: U16::new(LE, self.section_num), - time_date_stamp: U32::new(LE, header.time_date_stamp), - pointer_to_symbol_table: U32::new(LE, self.symtab_offset), - number_of_symbols: U32::new(LE, self.symtab_num), - size_of_optional_header: U16::default(), - characteristics: U16::new(LE, header.characteristics), - }; - self.buffer.write(&header); - - Ok(()) - } - - /// Reserve the range for the section headers. - pub fn reserve_section_headers(&mut self, section_num: u16) { - debug_assert_eq!(self.section_num, 0); - self.section_num = section_num; - self.reserve( - section_num as usize * mem::size_of::<pe::ImageSectionHeader>(), - 1, - ); - } - - /// Write a section header. - pub fn write_section_header(&mut self, section: SectionHeader) { - let mut coff_section = pe::ImageSectionHeader { - name: [0; 8], - virtual_size: U32::default(), - virtual_address: U32::default(), - size_of_raw_data: U32::new(LE, section.size_of_raw_data), - pointer_to_raw_data: U32::new(LE, section.pointer_to_raw_data), - pointer_to_relocations: U32::new(LE, section.pointer_to_relocations), - pointer_to_linenumbers: U32::new(LE, section.pointer_to_linenumbers), - number_of_relocations: if section.number_of_relocations > 0xffff { - U16::new(LE, 0xffff) - } else { - U16::new(LE, section.number_of_relocations as u16) - }, - number_of_linenumbers: U16::default(), - characteristics: U32::new(LE, section.characteristics), - }; - match section.name { - Name::Short(name) => coff_section.name = name, - Name::Long(str_id) => { - let mut str_offset = self.strtab.get_offset(str_id); - if str_offset <= 9_999_999 { - let mut name = [0; 7]; - let mut len = 0; - if str_offset == 0 { - name[6] = b'0'; - len = 1; - } else { - while str_offset != 0 { - let rem = (str_offset % 10) as u8; - str_offset /= 10; - name[6 - len] = b'0' + rem; - len += 1; - } - } - coff_section.name = [0; 8]; - coff_section.name[0] = b'/'; - coff_section.name[1..][..len].copy_from_slice(&name[7 - len..]); - } else { - debug_assert!(str_offset as u64 <= 0xf_ffff_ffff); - coff_section.name[0] = b'/'; - coff_section.name[1] = b'/'; - for i in 0..6 { - let rem = (str_offset % 64) as u8; - str_offset /= 64; - let c = match rem { - 0..=25 => b'A' + rem, - 26..=51 => b'a' + rem - 26, - 52..=61 => b'0' + rem - 52, - 62 => b'+', - 63 => b'/', - _ => unreachable!(), - }; - coff_section.name[7 - i] = c; - } - } - } - } - self.buffer.write(&coff_section); - } - - /// Reserve the range for the section data. - /// - /// Returns the aligned offset of the start of the range. - /// Does nothing and returns 0 if the length is zero. - pub fn reserve_section(&mut self, len: usize) -> u32 { - if len == 0 { - return 0; - } - // TODO: not sure what alignment is required here, but this seems to match LLVM - self.reserve(len, 4) - } - - /// Write the alignment bytes prior to section data. - /// - /// This is unneeded if you are using `write_section` or `write_section_zeroes` - /// for the data. - pub fn write_section_align(&mut self) { - util::write_align(self.buffer, 4); - } - - /// Write the section data. - /// - /// Writes alignment bytes prior to the data. - /// Does nothing if the data is empty. - pub fn write_section(&mut self, data: &[u8]) { - if data.is_empty() { - return; - } - self.write_section_align(); - self.buffer.write_bytes(data); - } - - /// Write the section data using zero bytes. - /// - /// Writes alignment bytes prior to the data. - /// Does nothing if the length is zero. - pub fn write_section_zeroes(&mut self, len: usize) { - if len == 0 { - return; - } - self.write_section_align(); - self.buffer.resize(self.buffer.len() + len); - } - - /// Reserve a file range for the given number of relocations. - /// - /// This will automatically reserve an extra relocation if there are more than 0xffff. - /// - /// Returns the offset of the range. - /// Does nothing and returns 0 if the count is zero. - pub fn reserve_relocations(&mut self, mut count: usize) -> u32 { - if count == 0 { - return 0; - } - if count > 0xffff { - count += 1; - } - self.reserve(count * mem::size_of::<pe::ImageRelocation>(), 1) - } - - /// Write a relocation containing the count if required. - /// - /// This should be called before writing the first relocation for a section. - pub fn write_relocations_count(&mut self, count: usize) { - if count > 0xffff { - let coff_relocation = pe::ImageRelocation { - virtual_address: U32Bytes::new(LE, count as u32 + 1), - symbol_table_index: U32Bytes::new(LE, 0), - typ: U16Bytes::new(LE, 0), - }; - self.buffer.write(&coff_relocation); - } - } - - /// Write a relocation. - pub fn write_relocation(&mut self, reloc: Relocation) { - let coff_relocation = pe::ImageRelocation { - virtual_address: U32Bytes::new(LE, reloc.virtual_address), - symbol_table_index: U32Bytes::new(LE, reloc.symbol), - typ: U16Bytes::new(LE, reloc.typ), - }; - self.buffer.write(&coff_relocation); - } - - /// Reserve a symbol table entry. - /// - /// This must be called before [`Self::reserve_symtab_strtab`]. - pub fn reserve_symbol_index(&mut self) -> u32 { - debug_assert_eq!(self.symtab_offset, 0); - let index = self.symtab_num; - self.symtab_num += 1; - index - } - - /// Reserve a number of symbol table entries. - pub fn reserve_symbol_indices(&mut self, count: u32) { - debug_assert_eq!(self.symtab_offset, 0); - self.symtab_num += count; - } - - /// Write a symbol table entry. - pub fn write_symbol(&mut self, symbol: Symbol) { - let mut coff_symbol = pe::ImageSymbol { - name: [0; 8], - value: U32Bytes::new(LE, symbol.value), - section_number: U16Bytes::new(LE, symbol.section_number), - typ: U16Bytes::new(LE, symbol.typ), - storage_class: symbol.storage_class, - number_of_aux_symbols: symbol.number_of_aux_symbols, - }; - match symbol.name { - Name::Short(name) => coff_symbol.name = name, - Name::Long(str_id) => { - let str_offset = self.strtab.get_offset(str_id); - coff_symbol.name[4..8].copy_from_slice(&u32::to_le_bytes(str_offset as u32)); - } - } - self.buffer.write(&coff_symbol); - } - - /// Reserve auxiliary symbols for a file name. - /// - /// Returns the number of auxiliary symbols required. - /// - /// This must be called before [`Self::reserve_symtab_strtab`]. - pub fn reserve_aux_file_name(&mut self, name: &[u8]) -> u8 { - debug_assert_eq!(self.symtab_offset, 0); - let aux_count = (name.len() + pe::IMAGE_SIZEOF_SYMBOL - 1) / pe::IMAGE_SIZEOF_SYMBOL; - self.symtab_num += aux_count as u32; - aux_count as u8 - } - - /// Write auxiliary symbols for a file name. - pub fn write_aux_file_name(&mut self, name: &[u8], aux_count: u8) { - let aux_len = aux_count as usize * pe::IMAGE_SIZEOF_SYMBOL; - debug_assert!(aux_len >= name.len()); - let old_len = self.buffer.len(); - self.buffer.write_bytes(name); - self.buffer.resize(old_len + aux_len); - } - - /// Reserve an auxiliary symbol for a section. - /// - /// Returns the number of auxiliary symbols required. - /// - /// This must be called before [`Self::reserve_symtab_strtab`]. - pub fn reserve_aux_section(&mut self) -> u8 { - debug_assert_eq!(self.symtab_offset, 0); - self.symtab_num += 1; - 1 - } - - /// Write an auxiliary symbol for a section. - pub fn write_aux_section(&mut self, section: AuxSymbolSection) { - let aux = pe::ImageAuxSymbolSection { - length: U32Bytes::new(LE, section.length), - number_of_relocations: if section.number_of_relocations > 0xffff { - U16Bytes::new(LE, 0xffff) - } else { - U16Bytes::new(LE, section.number_of_relocations as u16) - }, - number_of_linenumbers: U16Bytes::new(LE, section.number_of_linenumbers), - check_sum: U32Bytes::new(LE, section.check_sum), - number: U16Bytes::new(LE, section.number as u16), - selection: section.selection, - reserved: 0, - high_number: U16Bytes::new(LE, (section.number >> 16) as u16), - }; - self.buffer.write(&aux); - } - - /// Return the number of reserved symbol table entries. - pub fn symbol_count(&self) -> u32 { - self.symtab_num - } - - /// Add a string to the string table. - /// - /// This must be called before [`Self::reserve_symtab_strtab`]. - pub fn add_string(&mut self, name: &'a [u8]) -> StringId { - debug_assert_eq!(self.strtab_offset, 0); - self.strtab.add(name) - } - - /// Add a section or symbol name to the string table if required. - /// - /// This must be called before [`Self::reserve_symtab_strtab`]. - pub fn add_name(&mut self, name: &'a [u8]) -> Name { - if name.len() > 8 { - Name::Long(self.add_string(name)) - } else { - let mut short_name = [0; 8]; - short_name[..name.len()].copy_from_slice(name); - Name::Short(short_name) - } - } - - /// Reserve the range for the symbol table and string table. - /// - /// This must be called after functions that reserve symbol - /// indices or add strings. - pub fn reserve_symtab_strtab(&mut self) { - debug_assert_eq!(self.symtab_offset, 0); - self.symtab_offset = self.reserve(self.symtab_num as usize * pe::IMAGE_SIZEOF_SYMBOL, 1); - - debug_assert_eq!(self.strtab_offset, 0); - // First 4 bytes of strtab are the length. - self.strtab.write(4, &mut self.strtab_data); - self.strtab_len = self.strtab_data.len() + 4; - self.strtab_offset = self.reserve(self.strtab_len, 1); - } - - /// Write the string table. - pub fn write_strtab(&mut self) { - debug_assert_eq!(self.strtab_offset, self.buffer.len() as u32); - self.buffer - .write_bytes(&u32::to_le_bytes(self.strtab_len as u32)); - self.buffer.write_bytes(&self.strtab_data); - } -} - -/// Shortened and native endian version of [`pe::ImageFileHeader`]. -#[allow(missing_docs)] -#[derive(Debug, Default, Clone)] -pub struct FileHeader { - pub machine: u16, - pub time_date_stamp: u32, - pub characteristics: u16, -} - -/// A section or symbol name. -#[derive(Debug, Clone, Copy)] -pub enum Name { - /// An inline name. - Short([u8; 8]), - /// An id of a string table entry. - Long(StringId), -} - -impl Default for Name { - fn default() -> Name { - Name::Short([0; 8]) - } -} - -// From isn't useful. -#[allow(clippy::from_over_into)] -impl<'a> Into<Name> for &'a [u8; 8] { - fn into(self) -> Name { - Name::Short(*self) - } -} - -/// Native endian version of [`pe::ImageSectionHeader`]. -#[allow(missing_docs)] -#[derive(Debug, Default, Clone)] -pub struct SectionHeader { - pub name: Name, - pub size_of_raw_data: u32, - pub pointer_to_raw_data: u32, - pub pointer_to_relocations: u32, - pub pointer_to_linenumbers: u32, - /// This will automatically be clamped if there are more than 0xffff. - pub number_of_relocations: u32, - pub number_of_linenumbers: u16, - pub characteristics: u32, -} - -/// Native endian version of [`pe::ImageSymbol`]. -#[allow(missing_docs)] -#[derive(Debug, Default, Clone)] -pub struct Symbol { - pub name: Name, - pub value: u32, - pub section_number: u16, - pub typ: u16, - pub storage_class: u8, - pub number_of_aux_symbols: u8, -} - -/// Native endian version of [`pe::ImageAuxSymbolSection`]. -#[allow(missing_docs)] -#[derive(Debug, Default, Clone)] -pub struct AuxSymbolSection { - pub length: u32, - /// This will automatically be clamped if there are more than 0xffff. - pub number_of_relocations: u32, - pub number_of_linenumbers: u16, - pub check_sum: u32, - pub number: u32, - pub selection: u8, -} - -/// Native endian version of [`pe::ImageRelocation`]. -#[allow(missing_docs)] -#[derive(Debug, Default, Clone)] -pub struct Relocation { - pub virtual_address: u32, - pub symbol: u32, - pub typ: u16, -} |