diff options
Diffstat (limited to 'third_party/rust/object/src/write/elf/object.rs')
-rw-r--r-- | third_party/rust/object/src/write/elf/object.rs | 903 |
1 files changed, 903 insertions, 0 deletions
diff --git a/third_party/rust/object/src/write/elf/object.rs b/third_party/rust/object/src/write/elf/object.rs new file mode 100644 index 0000000000..acc820c9ec --- /dev/null +++ b/third_party/rust/object/src/write/elf/object.rs @@ -0,0 +1,903 @@ +use alloc::vec::Vec; + +use crate::write::elf::writer::*; +use crate::write::string::StringId; +use crate::write::*; +use crate::AddressSize; +use crate::{elf, pod}; + +#[derive(Clone, Copy)] +struct ComdatOffsets { + offset: usize, + str_id: StringId, +} + +#[derive(Clone, Copy)] +struct SectionOffsets { + index: SectionIndex, + offset: usize, + str_id: StringId, + reloc_offset: usize, + reloc_str_id: Option<StringId>, +} + +#[derive(Default, Clone, Copy)] +struct SymbolOffsets { + index: SymbolIndex, + str_id: Option<StringId>, +} + +// Public methods. +impl<'a> Object<'a> { + /// Add a property with a u32 value to the ELF ".note.gnu.property" section. + /// + /// Requires `feature = "elf"`. + pub fn add_elf_gnu_property_u32(&mut self, property: u32, value: u32) { + if self.format != BinaryFormat::Elf { + return; + } + + let align = if self.elf_is_64() { 8 } else { 4 }; + let mut data = Vec::with_capacity(32); + let n_name = b"GNU\0"; + data.extend_from_slice(pod::bytes_of(&elf::NoteHeader32 { + n_namesz: U32::new(self.endian, n_name.len() as u32), + n_descsz: U32::new(self.endian, util::align(3 * 4, align) as u32), + n_type: U32::new(self.endian, elf::NT_GNU_PROPERTY_TYPE_0), + })); + data.extend_from_slice(n_name); + // This happens to already be aligned correctly. + debug_assert_eq!(util::align(data.len(), align), data.len()); + data.extend_from_slice(pod::bytes_of(&U32::new(self.endian, property))); + // Value size + data.extend_from_slice(pod::bytes_of(&U32::new(self.endian, 4))); + data.extend_from_slice(pod::bytes_of(&U32::new(self.endian, value))); + util::write_align(&mut data, align); + + let section = self.section_id(StandardSection::GnuProperty); + self.append_section_data(section, &data, align as u64); + } +} + +// Private methods. +impl<'a> Object<'a> { + pub(crate) fn elf_section_info( + &self, + section: StandardSection, + ) -> (&'static [u8], &'static [u8], SectionKind, SectionFlags) { + match section { + StandardSection::Text => (&[], &b".text"[..], SectionKind::Text, SectionFlags::None), + StandardSection::Data => (&[], &b".data"[..], SectionKind::Data, SectionFlags::None), + StandardSection::ReadOnlyData | StandardSection::ReadOnlyString => ( + &[], + &b".rodata"[..], + SectionKind::ReadOnlyData, + SectionFlags::None, + ), + StandardSection::ReadOnlyDataWithRel => ( + &[], + b".data.rel.ro", + SectionKind::ReadOnlyDataWithRel, + SectionFlags::None, + ), + StandardSection::UninitializedData => ( + &[], + &b".bss"[..], + SectionKind::UninitializedData, + SectionFlags::None, + ), + StandardSection::Tls => (&[], &b".tdata"[..], SectionKind::Tls, SectionFlags::None), + StandardSection::UninitializedTls => ( + &[], + &b".tbss"[..], + SectionKind::UninitializedTls, + SectionFlags::None, + ), + StandardSection::TlsVariables => { + // Unsupported section. + (&[], &[], SectionKind::TlsVariables, SectionFlags::None) + } + StandardSection::Common => { + // Unsupported section. + (&[], &[], SectionKind::Common, SectionFlags::None) + } + StandardSection::GnuProperty => ( + &[], + &b".note.gnu.property"[..], + SectionKind::Note, + SectionFlags::Elf { + sh_flags: u64::from(elf::SHF_ALLOC), + }, + ), + } + } + + pub(crate) fn elf_subsection_name(&self, section: &[u8], value: &[u8]) -> Vec<u8> { + let mut name = section.to_vec(); + name.push(b'.'); + name.extend_from_slice(value); + name + } + + fn elf_has_relocation_addend(&self) -> Result<bool> { + Ok(match self.architecture { + Architecture::Aarch64 => true, + Architecture::Aarch64_Ilp32 => true, + Architecture::Arm => false, + Architecture::Avr => true, + Architecture::Bpf => false, + Architecture::Csky => true, + Architecture::I386 => false, + Architecture::X86_64 => true, + Architecture::X86_64_X32 => true, + Architecture::Hexagon => true, + Architecture::LoongArch64 => true, + Architecture::Mips => false, + Architecture::Mips64 => true, + Architecture::Msp430 => true, + Architecture::PowerPc => true, + Architecture::PowerPc64 => true, + Architecture::Riscv64 => true, + Architecture::Riscv32 => true, + Architecture::S390x => true, + Architecture::Sbf => false, + Architecture::Sparc64 => true, + Architecture::Xtensa => true, + _ => { + return Err(Error(format!( + "unimplemented architecture {:?}", + self.architecture + ))); + } + }) + } + + pub(crate) fn elf_fixup_relocation(&mut self, mut relocation: &mut Relocation) -> Result<i64> { + // Return true if we should use a section symbol to avoid preemption. + fn want_section_symbol(relocation: &Relocation, symbol: &Symbol) -> bool { + if symbol.scope != SymbolScope::Dynamic { + // Only dynamic symbols can be preemptible. + return false; + } + match symbol.kind { + SymbolKind::Text | SymbolKind::Data => {} + _ => return false, + } + match relocation.kind { + // Anything using GOT or PLT is preemptible. + // We also require that `Other` relocations must already be correct. + RelocationKind::Got + | RelocationKind::GotRelative + | RelocationKind::GotBaseRelative + | RelocationKind::PltRelative + | RelocationKind::Elf(_) => return false, + // Absolute relocations are preemptible for non-local data. + // TODO: not sure if this rule is exactly correct + // This rule was added to handle global data references in debuginfo. + // Maybe this should be a new relocation kind so that the caller can decide. + RelocationKind::Absolute => { + if symbol.kind == SymbolKind::Data { + return false; + } + } + _ => {} + } + true + } + + // Use section symbols for relocations where required to avoid preemption. + // Otherwise, the linker will fail with: + // relocation R_X86_64_PC32 against symbol `SomeSymbolName' can not be used when + // making a shared object; recompile with -fPIC + let symbol = &self.symbols[relocation.symbol.0]; + if want_section_symbol(relocation, symbol) { + if let Some(section) = symbol.section.id() { + relocation.addend += symbol.value as i64; + relocation.symbol = self.section_symbol(section); + } + } + + // Determine whether the addend is stored in the relocation or the data. + if self.elf_has_relocation_addend()? { + Ok(0) + } else { + let constant = relocation.addend; + relocation.addend = 0; + Ok(constant) + } + } + + pub(crate) fn elf_is_64(&self) -> bool { + match self.architecture.address_size().unwrap() { + AddressSize::U8 | AddressSize::U16 | AddressSize::U32 => false, + AddressSize::U64 => true, + } + } + + pub(crate) fn elf_write(&self, buffer: &mut dyn WritableBuffer) -> Result<()> { + // Create reloc section header names so we can reference them. + let is_rela = self.elf_has_relocation_addend()?; + let reloc_names: Vec<_> = self + .sections + .iter() + .map(|section| { + let mut reloc_name = Vec::with_capacity( + if is_rela { ".rela".len() } else { ".rel".len() } + section.name.len(), + ); + if !section.relocations.is_empty() { + reloc_name.extend_from_slice(if is_rela { + &b".rela"[..] + } else { + &b".rel"[..] + }); + reloc_name.extend_from_slice(§ion.name); + } + reloc_name + }) + .collect(); + + // Start calculating offsets of everything. + let mut writer = Writer::new(self.endian, self.elf_is_64(), buffer); + writer.reserve_file_header(); + + // Calculate size of section data. + let mut comdat_offsets = Vec::with_capacity(self.comdats.len()); + for comdat in &self.comdats { + if comdat.kind != ComdatKind::Any { + return Err(Error(format!( + "unsupported COMDAT symbol `{}` kind {:?}", + self.symbols[comdat.symbol.0].name().unwrap_or(""), + comdat.kind + ))); + } + + writer.reserve_section_index(); + let offset = writer.reserve_comdat(comdat.sections.len()); + let str_id = writer.add_section_name(b".group"); + comdat_offsets.push(ComdatOffsets { offset, str_id }); + } + let mut section_offsets = Vec::with_capacity(self.sections.len()); + for (section, reloc_name) in self.sections.iter().zip(reloc_names.iter()) { + let index = writer.reserve_section_index(); + let offset = writer.reserve(section.data.len(), section.align as usize); + let str_id = writer.add_section_name(§ion.name); + let mut reloc_str_id = None; + if !section.relocations.is_empty() { + writer.reserve_section_index(); + reloc_str_id = Some(writer.add_section_name(reloc_name)); + } + section_offsets.push(SectionOffsets { + index, + offset, + str_id, + // Relocation data is reserved later. + reloc_offset: 0, + reloc_str_id, + }); + } + + // Calculate index of symbols and add symbol strings to strtab. + let mut symbol_offsets = vec![SymbolOffsets::default(); self.symbols.len()]; + writer.reserve_null_symbol_index(); + // Local symbols must come before global. + for (index, symbol) in self.symbols.iter().enumerate() { + if symbol.is_local() { + let section_index = symbol.section.id().map(|s| section_offsets[s.0].index); + symbol_offsets[index].index = writer.reserve_symbol_index(section_index); + } + } + let symtab_num_local = writer.symbol_count(); + for (index, symbol) in self.symbols.iter().enumerate() { + if !symbol.is_local() { + let section_index = symbol.section.id().map(|s| section_offsets[s.0].index); + symbol_offsets[index].index = writer.reserve_symbol_index(section_index); + } + } + for (index, symbol) in self.symbols.iter().enumerate() { + if symbol.kind != SymbolKind::Section && !symbol.name.is_empty() { + symbol_offsets[index].str_id = Some(writer.add_string(&symbol.name)); + } + } + + // Calculate size of symbols. + writer.reserve_symtab_section_index(); + writer.reserve_symtab(); + if writer.symtab_shndx_needed() { + writer.reserve_symtab_shndx_section_index(); + } + writer.reserve_symtab_shndx(); + writer.reserve_strtab_section_index(); + writer.reserve_strtab(); + + // Calculate size of relocations. + for (index, section) in self.sections.iter().enumerate() { + let count = section.relocations.len(); + if count != 0 { + section_offsets[index].reloc_offset = writer.reserve_relocations(count, is_rela); + } + } + + // Calculate size of section headers. + writer.reserve_shstrtab_section_index(); + writer.reserve_shstrtab(); + writer.reserve_section_headers(); + + // Start writing. + let e_type = elf::ET_REL; + let e_machine = match self.architecture { + Architecture::Aarch64 => elf::EM_AARCH64, + Architecture::Aarch64_Ilp32 => elf::EM_AARCH64, + Architecture::Arm => elf::EM_ARM, + Architecture::Avr => elf::EM_AVR, + Architecture::Bpf => elf::EM_BPF, + Architecture::Csky => elf::EM_CSKY, + Architecture::I386 => elf::EM_386, + Architecture::X86_64 => elf::EM_X86_64, + Architecture::X86_64_X32 => elf::EM_X86_64, + Architecture::Hexagon => elf::EM_HEXAGON, + Architecture::LoongArch64 => elf::EM_LOONGARCH, + Architecture::Mips => elf::EM_MIPS, + Architecture::Mips64 => elf::EM_MIPS, + Architecture::Msp430 => elf::EM_MSP430, + Architecture::PowerPc => elf::EM_PPC, + Architecture::PowerPc64 => elf::EM_PPC64, + Architecture::Riscv32 => elf::EM_RISCV, + Architecture::Riscv64 => elf::EM_RISCV, + Architecture::S390x => elf::EM_S390, + Architecture::Sbf => elf::EM_SBF, + Architecture::Sparc64 => elf::EM_SPARCV9, + Architecture::Xtensa => elf::EM_XTENSA, + _ => { + return Err(Error(format!( + "unimplemented architecture {:?}", + self.architecture + ))); + } + }; + let (os_abi, abi_version, e_flags) = if let FileFlags::Elf { + os_abi, + abi_version, + e_flags, + } = self.flags + { + (os_abi, abi_version, e_flags) + } else { + (elf::ELFOSABI_NONE, 0, 0) + }; + writer.write_file_header(&FileHeader { + os_abi, + abi_version, + e_type, + e_machine, + e_entry: 0, + e_flags, + })?; + + // Write section data. + for comdat in &self.comdats { + writer.write_comdat_header(); + for section in &comdat.sections { + writer.write_comdat_entry(section_offsets[section.0].index); + } + } + for (index, section) in self.sections.iter().enumerate() { + writer.write_align(section.align as usize); + debug_assert_eq!(section_offsets[index].offset, writer.len()); + writer.write(§ion.data); + } + + // Write symbols. + writer.write_null_symbol(); + let mut write_symbol = |index: usize, symbol: &Symbol| -> Result<()> { + let st_info = if let SymbolFlags::Elf { st_info, .. } = symbol.flags { + st_info + } else { + let st_type = match symbol.kind { + SymbolKind::Null => elf::STT_NOTYPE, + SymbolKind::Text => { + if symbol.is_undefined() { + elf::STT_NOTYPE + } else { + elf::STT_FUNC + } + } + SymbolKind::Data => { + if symbol.is_undefined() { + elf::STT_NOTYPE + } else if symbol.is_common() { + elf::STT_COMMON + } else { + elf::STT_OBJECT + } + } + SymbolKind::Section => elf::STT_SECTION, + SymbolKind::File => elf::STT_FILE, + SymbolKind::Tls => elf::STT_TLS, + SymbolKind::Label => elf::STT_NOTYPE, + SymbolKind::Unknown => { + if symbol.is_undefined() { + elf::STT_NOTYPE + } else { + return Err(Error(format!( + "unimplemented symbol `{}` kind {:?}", + symbol.name().unwrap_or(""), + symbol.kind + ))); + } + } + }; + let st_bind = if symbol.weak { + elf::STB_WEAK + } else if symbol.is_undefined() { + elf::STB_GLOBAL + } else if symbol.is_local() { + elf::STB_LOCAL + } else { + elf::STB_GLOBAL + }; + (st_bind << 4) + st_type + }; + let st_other = if let SymbolFlags::Elf { st_other, .. } = symbol.flags { + st_other + } else if symbol.scope == SymbolScope::Linkage { + elf::STV_HIDDEN + } else { + elf::STV_DEFAULT + }; + let (st_shndx, section) = match symbol.section { + SymbolSection::None => { + debug_assert_eq!(symbol.kind, SymbolKind::File); + (elf::SHN_ABS, None) + } + SymbolSection::Undefined => (elf::SHN_UNDEF, None), + SymbolSection::Absolute => (elf::SHN_ABS, None), + SymbolSection::Common => (elf::SHN_COMMON, None), + SymbolSection::Section(id) => (0, Some(section_offsets[id.0].index)), + }; + writer.write_symbol(&Sym { + name: symbol_offsets[index].str_id, + section, + st_info, + st_other, + st_shndx, + st_value: symbol.value, + st_size: symbol.size, + }); + Ok(()) + }; + for (index, symbol) in self.symbols.iter().enumerate() { + if symbol.is_local() { + write_symbol(index, symbol)?; + } + } + for (index, symbol) in self.symbols.iter().enumerate() { + if !symbol.is_local() { + write_symbol(index, symbol)?; + } + } + writer.write_symtab_shndx(); + writer.write_strtab(); + + // Write relocations. + for (index, section) in self.sections.iter().enumerate() { + if !section.relocations.is_empty() { + writer.write_align_relocation(); + debug_assert_eq!(section_offsets[index].reloc_offset, writer.len()); + for reloc in §ion.relocations { + let r_type = match self.architecture { + Architecture::Aarch64 => match (reloc.kind, reloc.encoding, reloc.size) { + (RelocationKind::Absolute, RelocationEncoding::Generic, 64) => { + elf::R_AARCH64_ABS64 + } + (RelocationKind::Absolute, RelocationEncoding::Generic, 32) => { + elf::R_AARCH64_ABS32 + } + (RelocationKind::Absolute, RelocationEncoding::Generic, 16) => { + elf::R_AARCH64_ABS16 + } + (RelocationKind::Relative, RelocationEncoding::Generic, 64) => { + elf::R_AARCH64_PREL64 + } + (RelocationKind::Relative, RelocationEncoding::Generic, 32) => { + elf::R_AARCH64_PREL32 + } + (RelocationKind::Relative, RelocationEncoding::Generic, 16) => { + elf::R_AARCH64_PREL16 + } + (RelocationKind::Relative, RelocationEncoding::AArch64Call, 26) + | (RelocationKind::PltRelative, RelocationEncoding::AArch64Call, 26) => { + elf::R_AARCH64_CALL26 + } + (RelocationKind::Elf(x), _, _) => x, + _ => { + return Err(Error(format!("unimplemented relocation {:?}", reloc))); + } + }, + Architecture::Aarch64_Ilp32 => { + match (reloc.kind, reloc.encoding, reloc.size) { + (RelocationKind::Absolute, RelocationEncoding::Generic, 32) => { + elf::R_AARCH64_P32_ABS32 + } + (RelocationKind::Elf(x), _, _) => x, + _ => { + return Err(Error(format!( + "unimplemented relocation {:?}", + reloc + ))); + } + } + } + Architecture::Arm => match (reloc.kind, reloc.encoding, reloc.size) { + (RelocationKind::Absolute, _, 32) => elf::R_ARM_ABS32, + (RelocationKind::Elf(x), _, _) => x, + _ => { + return Err(Error(format!("unimplemented relocation {:?}", reloc))); + } + }, + Architecture::Avr => match (reloc.kind, reloc.encoding, reloc.size) { + (RelocationKind::Absolute, _, 32) => elf::R_AVR_32, + (RelocationKind::Absolute, _, 16) => elf::R_AVR_16, + (RelocationKind::Elf(x), _, _) => x, + _ => { + return Err(Error(format!("unimplemented relocation {:?}", reloc))); + } + }, + Architecture::Bpf => match (reloc.kind, reloc.encoding, reloc.size) { + (RelocationKind::Absolute, _, 64) => elf::R_BPF_64_64, + (RelocationKind::Absolute, _, 32) => elf::R_BPF_64_32, + (RelocationKind::Elf(x), _, _) => x, + _ => { + return Err(Error(format!("unimplemented relocation {:?}", reloc))); + } + }, + Architecture::Csky => match (reloc.kind, reloc.encoding, reloc.size) { + (RelocationKind::Absolute, _, 32) => elf::R_CKCORE_ADDR32, + (RelocationKind::Relative, RelocationEncoding::Generic, 32) => { + elf::R_CKCORE_PCREL32 + } + (RelocationKind::Elf(x), _, _) => x, + _ => { + return Err(Error(format!("unimplemented relocation {:?}", reloc))); + } + }, + Architecture::I386 => match (reloc.kind, reloc.size) { + (RelocationKind::Absolute, 32) => elf::R_386_32, + (RelocationKind::Relative, 32) => elf::R_386_PC32, + (RelocationKind::Got, 32) => elf::R_386_GOT32, + (RelocationKind::PltRelative, 32) => elf::R_386_PLT32, + (RelocationKind::GotBaseOffset, 32) => elf::R_386_GOTOFF, + (RelocationKind::GotBaseRelative, 32) => elf::R_386_GOTPC, + (RelocationKind::Absolute, 16) => elf::R_386_16, + (RelocationKind::Relative, 16) => elf::R_386_PC16, + (RelocationKind::Absolute, 8) => elf::R_386_8, + (RelocationKind::Relative, 8) => elf::R_386_PC8, + (RelocationKind::Elf(x), _) => x, + _ => { + return Err(Error(format!("unimplemented relocation {:?}", reloc))); + } + }, + Architecture::X86_64 | Architecture::X86_64_X32 => { + match (reloc.kind, reloc.encoding, reloc.size) { + (RelocationKind::Absolute, RelocationEncoding::Generic, 64) => { + elf::R_X86_64_64 + } + (RelocationKind::Relative, _, 32) => elf::R_X86_64_PC32, + (RelocationKind::Got, _, 32) => elf::R_X86_64_GOT32, + (RelocationKind::PltRelative, _, 32) => elf::R_X86_64_PLT32, + (RelocationKind::GotRelative, _, 32) => elf::R_X86_64_GOTPCREL, + (RelocationKind::Absolute, RelocationEncoding::Generic, 32) => { + elf::R_X86_64_32 + } + (RelocationKind::Absolute, RelocationEncoding::X86Signed, 32) => { + elf::R_X86_64_32S + } + (RelocationKind::Absolute, _, 16) => elf::R_X86_64_16, + (RelocationKind::Relative, _, 16) => elf::R_X86_64_PC16, + (RelocationKind::Absolute, _, 8) => elf::R_X86_64_8, + (RelocationKind::Relative, _, 8) => elf::R_X86_64_PC8, + (RelocationKind::Elf(x), _, _) => x, + _ => { + return Err(Error(format!( + "unimplemented relocation {:?}", + reloc + ))); + } + } + } + Architecture::Hexagon => match (reloc.kind, reloc.encoding, reloc.size) { + (RelocationKind::Absolute, _, 32) => elf::R_HEX_32, + (RelocationKind::Elf(x), _, _) => x, + _ => { + return Err(Error(format!("unimplemented relocation {:?}", reloc))); + } + }, + Architecture::LoongArch64 => match (reloc.kind, reloc.encoding, reloc.size) + { + (RelocationKind::Absolute, _, 32) => elf::R_LARCH_32, + (RelocationKind::Absolute, _, 64) => elf::R_LARCH_64, + (RelocationKind::Relative, _, 32) => elf::R_LARCH_32_PCREL, + (RelocationKind::Relative, RelocationEncoding::LoongArchBranch, 16) + | ( + RelocationKind::PltRelative, + RelocationEncoding::LoongArchBranch, + 16, + ) => elf::R_LARCH_B16, + (RelocationKind::Relative, RelocationEncoding::LoongArchBranch, 21) + | ( + RelocationKind::PltRelative, + RelocationEncoding::LoongArchBranch, + 21, + ) => elf::R_LARCH_B21, + (RelocationKind::Relative, RelocationEncoding::LoongArchBranch, 26) + | ( + RelocationKind::PltRelative, + RelocationEncoding::LoongArchBranch, + 26, + ) => elf::R_LARCH_B26, + (RelocationKind::Elf(x), _, _) => x, + _ => { + return Err(Error(format!("unimplemented relocation {:?}", reloc))); + } + }, + Architecture::Mips | Architecture::Mips64 => { + match (reloc.kind, reloc.encoding, reloc.size) { + (RelocationKind::Absolute, _, 16) => elf::R_MIPS_16, + (RelocationKind::Absolute, _, 32) => elf::R_MIPS_32, + (RelocationKind::Absolute, _, 64) => elf::R_MIPS_64, + (RelocationKind::Elf(x), _, _) => x, + _ => { + return Err(Error(format!( + "unimplemented relocation {:?}", + reloc + ))); + } + } + } + Architecture::Msp430 => match (reloc.kind, reloc.encoding, reloc.size) { + (RelocationKind::Absolute, _, 32) => elf::R_MSP430_32, + (RelocationKind::Absolute, _, 16) => elf::R_MSP430_16_BYTE, + (RelocationKind::Elf(x), _, _) => x, + _ => { + return Err(Error(format!("unimplemented relocation {:?}", reloc))); + } + }, + Architecture::PowerPc => match (reloc.kind, reloc.encoding, reloc.size) { + (RelocationKind::Absolute, _, 32) => elf::R_PPC_ADDR32, + (RelocationKind::Elf(x), _, _) => x, + _ => { + return Err(Error(format!("unimplemented relocation {:?}", reloc))); + } + }, + Architecture::PowerPc64 => match (reloc.kind, reloc.encoding, reloc.size) { + (RelocationKind::Absolute, _, 32) => elf::R_PPC64_ADDR32, + (RelocationKind::Absolute, _, 64) => elf::R_PPC64_ADDR64, + (RelocationKind::Elf(x), _, _) => x, + _ => { + return Err(Error(format!("unimplemented relocation {:?}", reloc))); + } + }, + Architecture::Riscv32 | Architecture::Riscv64 => { + match (reloc.kind, reloc.encoding, reloc.size) { + (RelocationKind::Absolute, _, 32) => elf::R_RISCV_32, + (RelocationKind::Absolute, _, 64) => elf::R_RISCV_64, + (RelocationKind::Relative, RelocationEncoding::Generic, 32) => { + elf::R_RISCV_32_PCREL + } + (RelocationKind::Elf(x), _, _) => x, + _ => { + return Err(Error(format!( + "unimplemented relocation {:?}", + reloc + ))); + } + } + } + Architecture::S390x => match (reloc.kind, reloc.encoding, reloc.size) { + (RelocationKind::Absolute, RelocationEncoding::Generic, 8) => { + elf::R_390_8 + } + (RelocationKind::Absolute, RelocationEncoding::Generic, 16) => { + elf::R_390_16 + } + (RelocationKind::Absolute, RelocationEncoding::Generic, 32) => { + elf::R_390_32 + } + (RelocationKind::Absolute, RelocationEncoding::Generic, 64) => { + elf::R_390_64 + } + (RelocationKind::Relative, RelocationEncoding::Generic, 16) => { + elf::R_390_PC16 + } + (RelocationKind::Relative, RelocationEncoding::Generic, 32) => { + elf::R_390_PC32 + } + (RelocationKind::Relative, RelocationEncoding::Generic, 64) => { + elf::R_390_PC64 + } + (RelocationKind::Relative, RelocationEncoding::S390xDbl, 16) => { + elf::R_390_PC16DBL + } + (RelocationKind::Relative, RelocationEncoding::S390xDbl, 32) => { + elf::R_390_PC32DBL + } + (RelocationKind::PltRelative, RelocationEncoding::S390xDbl, 16) => { + elf::R_390_PLT16DBL + } + (RelocationKind::PltRelative, RelocationEncoding::S390xDbl, 32) => { + elf::R_390_PLT32DBL + } + (RelocationKind::Got, RelocationEncoding::Generic, 16) => { + elf::R_390_GOT16 + } + (RelocationKind::Got, RelocationEncoding::Generic, 32) => { + elf::R_390_GOT32 + } + (RelocationKind::Got, RelocationEncoding::Generic, 64) => { + elf::R_390_GOT64 + } + (RelocationKind::GotRelative, RelocationEncoding::S390xDbl, 32) => { + elf::R_390_GOTENT + } + (RelocationKind::GotBaseOffset, RelocationEncoding::Generic, 16) => { + elf::R_390_GOTOFF16 + } + (RelocationKind::GotBaseOffset, RelocationEncoding::Generic, 32) => { + elf::R_390_GOTOFF32 + } + (RelocationKind::GotBaseOffset, RelocationEncoding::Generic, 64) => { + elf::R_390_GOTOFF64 + } + (RelocationKind::GotBaseRelative, RelocationEncoding::Generic, 64) => { + elf::R_390_GOTPC + } + (RelocationKind::GotBaseRelative, RelocationEncoding::S390xDbl, 32) => { + elf::R_390_GOTPCDBL + } + (RelocationKind::Elf(x), _, _) => x, + _ => { + return Err(Error(format!("unimplemented relocation {:?}", reloc))); + } + }, + Architecture::Sbf => match (reloc.kind, reloc.encoding, reloc.size) { + (RelocationKind::Absolute, _, 64) => elf::R_SBF_64_64, + (RelocationKind::Absolute, _, 32) => elf::R_SBF_64_32, + (RelocationKind::Elf(x), _, _) => x, + _ => { + return Err(Error(format!("unimplemented relocation {:?}", reloc))); + } + }, + Architecture::Sparc64 => match (reloc.kind, reloc.encoding, reloc.size) { + // TODO: use R_SPARC_32/R_SPARC_64 if aligned. + (RelocationKind::Absolute, _, 32) => elf::R_SPARC_UA32, + (RelocationKind::Absolute, _, 64) => elf::R_SPARC_UA64, + (RelocationKind::Elf(x), _, _) => x, + _ => { + return Err(Error(format!("unimplemented relocation {:?}", reloc))); + } + }, + Architecture::Xtensa => match (reloc.kind, reloc.encoding, reloc.size) { + (RelocationKind::Absolute, _, 32) => elf::R_XTENSA_32, + (RelocationKind::Relative, RelocationEncoding::Generic, 32) => { + elf::R_XTENSA_32_PCREL + } + (RelocationKind::Elf(x), _, _) => x, + _ => { + return Err(Error(format!("unimplemented relocation {:?}", reloc))); + } + }, + _ => { + if let RelocationKind::Elf(x) = reloc.kind { + x + } else { + return Err(Error(format!("unimplemented relocation {:?}", reloc))); + } + } + }; + let r_sym = symbol_offsets[reloc.symbol.0].index.0; + writer.write_relocation( + is_rela, + &Rel { + r_offset: reloc.offset, + r_sym, + r_type, + r_addend: reloc.addend, + }, + ); + } + } + } + + writer.write_shstrtab(); + + // Write section headers. + writer.write_null_section_header(); + + let symtab_index = writer.symtab_index(); + for (comdat, comdat_offset) in self.comdats.iter().zip(comdat_offsets.iter()) { + writer.write_comdat_section_header( + comdat_offset.str_id, + symtab_index, + symbol_offsets[comdat.symbol.0].index, + comdat_offset.offset, + comdat.sections.len(), + ); + } + for (index, section) in self.sections.iter().enumerate() { + let sh_type = match section.kind { + SectionKind::UninitializedData | SectionKind::UninitializedTls => elf::SHT_NOBITS, + SectionKind::Note => elf::SHT_NOTE, + SectionKind::Elf(sh_type) => sh_type, + _ => elf::SHT_PROGBITS, + }; + let sh_flags = if let SectionFlags::Elf { sh_flags } = section.flags { + sh_flags + } else { + match section.kind { + SectionKind::Text => elf::SHF_ALLOC | elf::SHF_EXECINSTR, + SectionKind::Data | SectionKind::ReadOnlyDataWithRel => { + elf::SHF_ALLOC | elf::SHF_WRITE + } + SectionKind::Tls => elf::SHF_ALLOC | elf::SHF_WRITE | elf::SHF_TLS, + SectionKind::UninitializedData => elf::SHF_ALLOC | elf::SHF_WRITE, + SectionKind::UninitializedTls => elf::SHF_ALLOC | elf::SHF_WRITE | elf::SHF_TLS, + SectionKind::ReadOnlyData => elf::SHF_ALLOC, + SectionKind::ReadOnlyString => { + elf::SHF_ALLOC | elf::SHF_STRINGS | elf::SHF_MERGE + } + SectionKind::OtherString => elf::SHF_STRINGS | elf::SHF_MERGE, + SectionKind::Other + | SectionKind::Debug + | SectionKind::Metadata + | SectionKind::Linker + | SectionKind::Note + | SectionKind::Elf(_) => 0, + SectionKind::Unknown | SectionKind::Common | SectionKind::TlsVariables => { + return Err(Error(format!( + "unimplemented section `{}` kind {:?}", + section.name().unwrap_or(""), + section.kind + ))); + } + } + .into() + }; + // TODO: not sure if this is correct, maybe user should determine this + let sh_entsize = match section.kind { + SectionKind::ReadOnlyString | SectionKind::OtherString => 1, + _ => 0, + }; + writer.write_section_header(&SectionHeader { + name: Some(section_offsets[index].str_id), + sh_type, + sh_flags, + sh_addr: 0, + sh_offset: section_offsets[index].offset as u64, + sh_size: section.size, + sh_link: 0, + sh_info: 0, + sh_addralign: section.align, + sh_entsize, + }); + + if !section.relocations.is_empty() { + writer.write_relocation_section_header( + section_offsets[index].reloc_str_id.unwrap(), + section_offsets[index].index, + symtab_index, + section_offsets[index].reloc_offset, + section.relocations.len(), + is_rela, + ); + } + } + + writer.write_symtab_section_header(symtab_num_local); + writer.write_symtab_shndx_section_header(); + writer.write_strtab_section_header(); + writer.write_shstrtab_section_header(); + + debug_assert_eq!(writer.reserved_len(), writer.len()); + + Ok(()) + } +} |