From 08d1c71c94498f2bf15050deaa436b7d45905bbe Mon Sep 17 00:00:00 2001 From: Stephen Wilson Date: Tue, 13 Jul 2010 00:24:59 +0000 Subject: [PATCH] Bring ELF64 on par with ELF32, add a few magic constants and support ".dynamic" section entries. llvm-svn: 108221 --- llvm/include/llvm/Support/ELF.h | 134 +++++++++++++++++++++++++++++--- 1 file changed, 123 insertions(+), 11 deletions(-) diff --git a/llvm/include/llvm/Support/ELF.h b/llvm/include/llvm/Support/ELF.h index eadb4283a645..6f939e7e3435 100644 --- a/llvm/include/llvm/Support/ELF.h +++ b/llvm/include/llvm/Support/ELF.h @@ -10,11 +10,10 @@ // This header contains common, non-processor-specific data structures and // constants for the ELF file format. // -// The details of the ELF32 bits in this file are largely based on -// the Tool Interface Standard (TIS) Executable and Linking Format -// (ELF) Specification Version 1.2, May 1995. The ELF64 stuff is not -// standardized, as far as I can tell. It was largely based on information -// I found in OpenBSD header files. +// The details of the ELF32 bits in this file are largely based on the Tool +// Interface Standard (TIS) Executable and Linking Format (ELF) Specification +// Version 1.2, May 1995. The ELF64 stuff is based on ELF-64 Object File Format +// Version 1.5, Draft 2, May 1998 as well as OpenBSD header files. // //===----------------------------------------------------------------------===// @@ -47,8 +46,23 @@ typedef uint16_t Elf64_Quarter; // Object file magic string. static const char ElfMagic[] = { 0x7f, 'E', 'L', 'F', '\0' }; +// e_ident size and indices. +enum { + EI_MAG0 = 0, // File identification index. + EI_MAG1 = 1, // File identification index. + EI_MAG2 = 2, // File identification index. + EI_MAG3 = 3, // File identification index. + EI_CLASS = 4, // File class. + EI_DATA = 5, // Data encoding. + EI_VERSION = 6, // File version. + EI_OSABI = 7, // OS/ABI identification. + EI_ABIVERSION = 8, // ABI version. + EI_PAD = 9, // Start of padding bytes. + EI_NIDENT = 16 // Number of bytes in e_ident. +}; + struct Elf32_Ehdr { - unsigned char e_ident[16]; // ELF Identification bytes + unsigned char e_ident[EI_NIDENT]; // ELF Identification bytes Elf32_Half e_type; // Type of file (see ET_* below) Elf32_Half e_machine; // Required architecture for this file (see EM_*) Elf32_Word e_version; // Must be equal to 1 @@ -65,14 +79,14 @@ struct Elf32_Ehdr { bool checkMagic() const { return (memcmp(e_ident, ElfMagic, strlen(ElfMagic))) == 0; } - unsigned char getFileClass() const { return e_ident[4]; } - unsigned char getDataEncoding() { return e_ident[5]; } + unsigned char getFileClass() const { return e_ident[EI_CLASS]; } + unsigned char getDataEncoding() const { return e_ident[EI_DATA]; } }; // 64-bit ELF header. Fields are the same as for ELF32, but with different // types (see above). struct Elf64_Ehdr { - unsigned char e_ident[16]; + unsigned char e_ident[EI_NIDENT]; Elf64_Quarter e_type; Elf64_Quarter e_machine; Elf64_Half e_version; @@ -86,6 +100,11 @@ struct Elf64_Ehdr { Elf64_Quarter e_shentsize; Elf64_Quarter e_shnum; Elf64_Quarter e_shstrndx; + bool checkMagic() const { + return (memcmp(e_ident, ElfMagic, strlen(ElfMagic))) == 0; + } + unsigned char getFileClass() const { return e_ident[EI_CLASS]; } + unsigned char getDataEncoding() const { return e_ident[EI_DATA]; } }; // File types @@ -117,6 +136,7 @@ enum { EM_860 = 7, // Intel 80860 EM_MIPS = 8, // MIPS R3000 EM_PPC = 20, // PowerPC + EM_PPC64 = 21, // PowerPC64 EM_ARM = 40, // ARM EM_ALPHA = 41, // DEC Alpha EM_SPARCV9 = 43, // SPARC V9 @@ -131,6 +151,7 @@ enum { // Object file byte orderings. enum { + ELFDATANONE = 0, // Invalid data encoding. ELFDATA2LSB = 1, // Little-endian object file ELFDATA2MSB = 2 // Big-endian object file }; @@ -262,7 +283,7 @@ enum { SHF_MASKPROC = 0xf0000000 // Bits indicating processor-specific flags. }; -// Symbol table entries. +// Symbol table entries for ELF32. struct Elf32_Sym { Elf32_Word st_name; // Symbol name (index into string table) Elf32_Addr st_value; // Value or address associated with the symbol @@ -282,6 +303,26 @@ struct Elf32_Sym { } }; +// Symbol table entries for ELF64. +struct Elf64_Sym { + Elf64_Word st_name; // Symbol name (index into string table) + unsigned char st_info; // Symbol's type and binding attributes + unsigned char st_other; // Must be zero; reserved + Elf64_Half st_shndx; // Which section (header table index) it's defined in + Elf64_Addr st_value; // Value or address associated with the symbol + Elf64_Xword st_size; // Size of the symbol + + // These accessors and mutators are identical to those defined for ELF32 + // symbol table entries. + unsigned char getBinding() const { return st_info >> 4; } + unsigned char getType() const { return st_info & 0x0f; } + void setBinding(unsigned char b) { setBindingAndType(b, getType()); } + void setType(unsigned char t) { setBindingAndType(getBinding(), t); } + void setBindingAndType(unsigned char b, unsigned char t) { + st_info = (b << 4) + (t & 0x0f); + } +}; + // Symbol bindings. enum { STB_LOCAL = 0, // Local symbol, not visible outside obj file containing def @@ -372,7 +413,7 @@ struct Elf64_Rela { }; }; -// Program header. +// Program header for ELF32. struct Elf32_Phdr { Elf32_Word p_type; // Type of segment Elf32_Off p_offset; // File offset where segment is located, in bytes @@ -384,6 +425,18 @@ struct Elf32_Phdr { Elf32_Word p_align; // Segment alignment constraint }; +// Program header for ELF64. +struct Elf64_Phdr { + Elf64_Word p_type; // Type of segment + Elf64_Word p_flags; // Segment flags + Elf64_Off p_offset; // File offset where segment is located, in bytes + Elf64_Addr p_vaddr; // Virtual address of beginning of segment + Elf64_Addr p_paddr; // Physical address of beginning of segment (OS-specific) + Elf64_Xword p_filesz; // Num. of bytes in file image of segment (may be zero) + Elf64_Xword p_memsz; // Num. of bytes in mem image of segment (may be zero) + Elf64_Xword p_align; // Segment alignment constraint +}; + // Segment types. enum { PT_NULL = 0, // Unused segment. @@ -405,6 +458,65 @@ enum { PF_MASKPROC = 0xf0000000 // Unspecified }; +// Dynamic table entry for ELF32. +struct Elf32_Dyn +{ + Elf32_Sword d_tag; // Type of dynamic table entry. + union + { + Elf32_Word d_val; // Integer value of entry. + Elf32_Addr d_ptr; // Pointer value of entry. + } d_un; +}; + +// Dynamic table entry for ELF64. +struct Elf64_Dyn +{ + Elf64_Sxword d_tag; // Type of dynamic table entry. + union + { + Elf64_Xword d_val; // Integer value of entry. + Elf64_Addr d_ptr; // Pointer value of entry. + } d_un; +}; + +// Dynamic table entry tags. +enum { + DT_NULL = 0, // Marks end of dynamic array. + DT_NEEDED = 1, // String table offset of needed library. + DT_PLTRELSZ = 2, // Size of relocation entries in PLT. + DT_PLTGOT = 3, // Address associated with linkage table. + DT_HASH = 4, // Address of symbolic hash table. + DT_STRTAB = 5, // Address of dynamic string table. + DT_SYMTAB = 6, // Address of dynamic symbol table. + DT_RELA = 7, // Address of relocation table (Rela entries). + DT_RELASZ = 8, // Size of Rela relocation table. + DT_RELAENT = 9, // Size of a Rela relocation entry. + DT_STRSZ = 10, // Total size of the string table. + DT_SYMENT = 11, // Size of a symbol table entry. + DT_INIT = 12, // Address of initialization function. + DT_FINI = 13, // Address of termination function. + DT_SONAME = 14, // String table offset of a shared objects name. + DT_RPATH = 15, // String table offset of library search path. + DT_SYMBOLIC = 16, // Changes symbol resolution algorithm. + DT_REL = 17, // Address of relocation table (Rel entries). + DT_RELSZ = 18, // Size of Rel relocation table. + DT_RELENT = 19, // Size of a Rel relocation entry. + DT_PLTREL = 20, // Type of relocation entry used for linking. + DT_DEBUG = 21, // Reserved for debugger. + DT_TEXTREL = 22, // Relocations exist for non-writable segements. + DT_JMPREL = 23, // Address of relocations associated with PLT. + DT_BIND_NOW = 24, // Process all relocations before execution. + DT_INIT_ARRAY = 25, // Pointer to array of initialization functions. + DT_FINI_ARRAY = 26, // Pointer to array of termination functions. + DT_INIT_ARRAYSZ = 27, // Size of DT_INIT_ARRAY. + DT_FINI_ARRAYSZ = 28, // Size of DT_FINI_ARRAY. + DT_LOOS = 0x60000000, // Start of environment specific tags. + DT_HIOS = 0x6FFFFFFF, // End of environment specific tags. + DT_LOPROC = 0x70000000, // Start of processor specific tags. + DT_HIPROC = 0x7FFFFFFF // End of processor specific tags. +}; + } // end namespace ELF } // end namespace llvm