#pragma once #include // --> begin ==============EHDR===================== // Reference: https://docs.oracle.com/cd/E23824_01/html/819-0690/chapter6-43405.html#scrolltoc // ====== ELF32 Header中的数据类型定义 ==== typedef uint32_t Elf32_Addr; typedef uint16_t Elf32_Half; typedef uint32_t Elf32_Off; typedef uint32_t Elf32_SWord; typedef uint32_t Elf32_Word; // ====== ELF64 Header中的数据类型定义 ==== typedef uint64_t Elf64_Addr; typedef uint16_t Elf64_Half; typedef uint64_t Elf64_Off; typedef uint32_t Elf64_Sword; typedef uint32_t Elf64_Word; typedef uint64_t Elf64_Xword; typedef uint64_t Elf64_Sxword; // ====== ELF Identification Index ====== // Purpose: File identification #define EI_MAG0 0 #define EI_MAG1 1 #define EI_MAG2 2 #define EI_MAG3 3 // Purpose: File class #define EI_CLASS 4 // Purpose: Data encoding #define EI_DATA 5 // Purpose: File version #define EI_VERSION 6 // e_ident[EI_VERSION]指定了ELF header的版本号 当前这个值必须是EV_CURRENT // Purpose: Operating system/ABI identification #define EI_OSABI 7 // e_ident[EI_OSABI]指定了操作系统以及对象所对应的ABI // Purpose: ABI version #define EI_ABIVERSION 8 // e_ident[EI_ABIVERSION] 指定了对象所对应的ABI版本. // Purpose: Start of padding bytes #define EI_PAD 9 // 这个值标志了e_ident中未使用字节的的起始下标 // Purpose: Size of e_ident[] #define EI_NIDENT 16 // EI_MAG0 - EI_MAG3 这是一个4byte的 magic number #define ELFMAG0 0x7f #define ELFMAG1 'E' #define ELFMAG2 'L' #define ELFMAG3 'F' // EI_CLASS e_ident[EI_CLASS]指明了文件的类型或capacity #define ELFCLASSNONE 0 // Invalid class #define ELFCLASS32 1 // 32–bit objects #define ELFCLASS64 2 // 64–bit objects // EI_DATA e_ident[EI_DATA]指明了与处理器相关的数据的编码方式 #define ELFDATANONE 0 #define ELFDATA2LSB 1 // 小端对齐 #define ELFDATA2MSB 2 // 大端对齐 // ELF e_type的类型定义 #define ET_NONE 0 // No file type #define ET_REL 1 // Relocatable file #define ET_EXEC 2 // Executable file #define ET_DYN 3 // Shared object file #define ET_CORE 4 // Core file #define ET_LOPROC 0xff00 // Processor-specific #define ET_HIPROC 0xffff // Processor-specific // e_machine的类型定义 #define EM_NONE 0 // No machine #define EM_SPARC 2 // SPARC #define EM_386 3 // Intel 80386 #define EM_SPARC32PLUS 18 // Sun SPARC 32+ #define EM_SPARCV9 43 // SPARC V9 #define EM_AMD64 62 // AMD 64 // e_version的类型定义 #define EV_NONE 0 // Invalid Version // EV_CURRENT: Value>=1 means current version // e_flags 定义 // e_flags for SPARC #define EF_SPARC_EXT_MASK 0xffff00 // Vendor Extension mask #define EF_SPARC_32PLUS 0x000100 // Generic V8+ features #define EF_SPARC_SUN_US1 0x000200 // Sun UltraSPARC 1 Extensions #define EF_SPARC_HAL_R1 0x000400 // HAL R1 Extensions #define EF_SPARC_SUN_US3 0x000800 // Sun UltraSPARC 3 Extensions #define EF_SPARCV9_MM 0x3 // Mask for Memory Model #define EF_SPARCV9_TSO 0x0 // Total Store Ordering #define EF_SPARCV9_PSO 0x1 // Partial Store Ordering #define EF_SPARCV9_RMO 0x2 // Relaxed Memory Ordering #define PN_XNUM 0xffff typedef struct { unsigned char e_ident[EI_NIDENT]; Elf32_Half e_type; Elf32_Half e_machine; Elf32_Word e_version; Elf32_Addr e_entry; Elf32_Off e_phoff; Elf32_Off e_shoff; Elf32_Word e_flags; Elf32_Half e_ehsize; Elf32_Half e_phentsize; Elf32_Half e_phnum; Elf32_Half e_shentsize; Elf32_Half e_shnum; Elf32_Half e_shstrndx; } Elf32_Ehdr; typedef struct { unsigned char e_ident[EI_NIDENT]; // 标志字节，这些字节与机器架构类型无关。目的是为了告诉我们如何解析这个文件的内容 Elf64_Half e_type; // 文件类型标志符 Elf64_Half e_machine; // 该文件依赖的处理器架构类型 Elf64_Word e_version; // 对象文件的版本 Elf64_Addr e_entry; // 进程的虚拟地址入点，使用字节偏移量表示。如果没有entry point，则该值为0 Elf64_Off e_phoff; // The program header table's file offset in bytes. 若没有，则为0 Elf64_Off e_shoff; // The section header table's file offset in bytes. 若没有，则为0 Elf64_Word e_flags; // 与处理器相关联的flags。格式为： EF_machine_flag 如果是x86架构，那么该值为0 Elf64_Half e_ehsize; // ELF Header的大小（单位：字节） Elf64_Half e_phentsize; // 程序的program header table中的一个entry的大小（所有的entry大小相同） Elf64_Half e_phnum; // program header table的entry数量 // e_phentsize*e_phnum=program header table的大小 // 如果没有program header table，该值为0 // 如果entry num>=PN_XNUM(0xffff), 那么该值为0xffff，且真实的pht的entry数量存储在section header的sh_info中（index=0） // 其他情况下，第一个section header entry的sh_info的值为0 Elf64_Half e_shentsize; // 每个section header的大小（字节 // 每个section header是section header table的一个entry Elf64_Half e_shnum; // section header table的entry数量 // e_shentsize*e_shnum=section header table的大小 // 如果没有section header table，那么该值为0 // 如果section的数量>=SHN_LORESERVE(0xff00)，那么该值为0，且真实的section数量存储在 // section header at index 0的sh_size变量中，否则第一个sh_size为0 Elf64_Half e_shstrndx; // 与section name string表相关联的section header table的entry的索引下标 // 如果没有name string table,那么该值等于SHN_UNDEF // 如果对应的index>=SHN_LORESERVE(0xff00)， 那么该变量值为SHN_XINDEX(0xffff) // 且真正的section name string table的index被存放在section header的index=0处的sh_link变量中 // 否则初始section header entry的sh_link变量为0 } Elf64_Ehdr; // --> end ==============EHDR===================== // --> begin ==============SHDR===================== // reference: https://docs.oracle.com/cd/E23824_01/html/819-0690/chapter6-94076.html#scrolltoc // ===== ELF Special Section Indexes ===== #define SHN_UNDEF 0 // An undefined, missing, irrelevant, or otherwise meaningless section reference. #define SHN_LORESERVE 0xff00 // The lower boundary of the range of reserved indexes. // The system reserves indexes between SHN_LORESERVE and SHN_HIRESERVE, inclusive. #define SHN_LOPROC 0xff00 // SHN_LOPROC - SHN_HIPROC 这个范围以内的数据为处理器特定的语义所保留 #define SHN_BEFORE 0xff00 // SHN_BEFORE, SHN_AFTER 与SHF_LINK_ORDER及SHF_ORDERED section flags一起，提供初始和终止section的 #define SHN_AFTER 0xff01 #define SHN_AMD64_LCOMMON 0xff02 // x64 specific common block label. This label is similar to SHN_COMMON, but provides for identifying a large common block. #define SHN_HIPROC 0xff1f #define SHN_LOOS 0xff20 // SHN_LOOS - SHN_HIOS 这个范围你的数为操作系统特定的语义所保留 #define SHN_LOSUNW 0xff3f // SHN_LOSUNW - SHN_HISUNW Values in this inclusive range are reserved for Sun-specific semantics. #define SHN_SUNW_IGNORE 0xff3f // This section index provides a temporary symbol definition within relocatable objects. Reserved for internal use by dtrace(1M). #define SHN_HISUNW 0xff3f #define SHN_HIOS 0xff3f #define SHN_ABS 0xfff1 // 对应的引用的绝对值。 举个例子，symbols defined relative to section number SHN_ABS have absolute values and are not affected by relocation. #define SHN_COMMON 0xfff2 // Symbols defined relative to this section are common symbols #define SHN_XINDEX 0xffff #define SHN_HIRESERVE 0xffff // The upper boundary of the range of reserved indexes. /* Note - Although index 0 is reserved as the undefined value, the section header table contains an entry for index 0. That is, if the e_shnum member of the ELF header indicates a file has 6 entries in the section header table, the sections have the indexes 0 through 5. The contents of the initial entry are specified later in this section. */ typedef struct { Elf32_Word sh_name; Elf32_Word sh_type; Elf32_Word sh_flags; Elf32_Addr sh_addr; Elf32_Off sh_offset; Elf32_Word sh_size; Elf32_Word sh_link; Elf32_Word sh_info; Elf32_Word sh_addralign; Elf32_Word sh_entsize; } Elf32_Shdr; typedef struct { Elf64_Word sh_name; // 段名 Elf64_Word sh_type; // 段的类型（按照内容和语义来分类） Elf64_Xword sh_flags; Elf64_Addr sh_addr; // 该section在进程的内存空间中的基地址。如果该段不需要出现在内存中，该值为0 Elf64_Off sh_offset; // The byte offset from the beginning of the file to the first byte in the section // 对于一个 SHT_NOBITS section，这个变量指的是概念上的偏移量。因为这种段并不是真正存在于文件中 Elf64_Xword sh_size; // The section's size in bytes(如果是SHT_NOBITS类型的section，section不会在文件中真正占用sh_size的空间) Elf64_Word sh_link; // A section header table index link, whose interpretation depends on the section type. Elf64_Word sh_info; // 依赖于section type来解析的额外的信息。如果sh_flags有SHF_INFO_LINK属性，那么这个变量代表一个section header table index. Elf64_Xword sh_addralign; // 地址按照多少bytes对齐。只允许使用2的n次幂的值。如果值为0或1，则意味着地址没有对齐要求。 Elf64_Xword sh_entsize; // 如果某个段拥有指定size的entry，则在这里指定，否则为0 } Elf64_Shdr; // ELF Section Types, sh_type #define SHT_NULL 0 #define SHT_PROGBITS 1 #define SHT_SYMTAB 2 // Identifies a symbol table #define SHT_STRTAB 3 // Identifies a string table. #define SHT_RELA 4 #define SHT_HASH 5 #define SHT_DYNAMIC 6 #define SHT_NOTE 7 #define SHT_NOBITS 8 #define SHT_REL 9 #define SHT_SHLIB 10 #define SHT_DYNSYM 11 // Identifies a symbol table #define SHT_INIT_ARRAY 14 #define SHT_FINI_ARRAY 15 #define SHT_PREINIT_ARRAY 16 #define SHT_GROUP 17 #define SHT_SYMTAB_SHNDX 18 #define SHT_LOOS 0x60000000 #define SHT_LOSUNW 0x6fffffef #define SHT_SUNW_capchain 0x6fffffef #define SHT_SUNW_capinfo 0x6ffffff0 #define SHT_SUNW_symsort 0x6ffffff1 #define SHT_SUNW_tlssort 0x6ffffff2 #define SHT_SUNW_LDYNSYM 0x6ffffff3 // Identifies a symbol table #define SHT_SUNW_dof 0x6ffffff4 #define SHT_SUNW_cap 0x6ffffff5 #define SHT_SUNW_SIGNATURE 0x6ffffff6 #define SHT_SUNW_ANNOTATE 0x6ffffff7 #define SHT_SUNW_DEBUGSTR 0x6ffffff8 #define SHT_SUNW_DEBUG 0x6ffffff9 #define SHT_SUNW_move 0x6ffffffa #define SHT_SUNW_COMDAT 0x6ffffffb #define SHT_SUNW_syminfo 0x6ffffffc #define SHT_SUNW_verdef 0x6ffffffd #define SHT_SUNW_verneed 0x6ffffffe #define SHT_SUNW_versym 0x6fffffff #define SHT_HISUNW 0x6fffffff #define SHT_HIOS 0x6fffffff #define SHT_LOPROC 0x70000000 #define SHT_SPARC_GOTDATA 0x70000000 #define SHT_AMD64_UNWIND 0x70000001 #define SHT_HIPROC 0x7fffffff #define SHT_LOUSER 0x80000000 #define SHT_HIUSER 0xffffffff // ELF Section Attribute Flags #define SHF_WRITE 0x1 // Identifies a section that should be writable during process execution #define SHF_ALLOC 0x2 // Identifies a section that occupies memory during process execution #define SHF_EXECINSTR 0x4 // contains executable machine instructions #define SHF_MERGE 0x10 #define SHF_STRINGS 0x20 #define SHF_INFO_LINK 0x40 // This section headers sh_info field holds a section header table index #define SHF_LINK_ORDER 0x80 // This section adds special ordering requirements to the link-editor #define SHF_OS_NONCONFORMING 0x100 #define SHF_GROUP 0x200 #define SHF_TLS 0x400 #define SHF_MASKOS 0x0ff00000 #define SHF_AMD64_LARGE 0x10000000 // identifies a section that can hold more than 2 Gbyte #define SHF_ORDERED 0x40000000 #define SHF_EXCLUDE 0x80000000 #define SHF_MASKPROC 0xf0000000 // --> end ==============SHDR===================== // --> begin ========== symbol table section ====== typedef struct { Elf32_Word st_name; Elf32_Addr st_value; Elf32_Word st_size; unsigned char st_info; unsigned char st_other; Elf32_Half st_shndx; } Elf32_Sym; typedef struct { Elf64_Word st_name; unsigned char st_info; unsigned char st_other; Elf64_Half st_shndx; Elf64_Addr st_value; Elf64_Xword st_size; } Elf64_Sym; // --> end ========== symbol table section ====== // --> begin ========== program header ========= // Ref: https://docs.oracle.com/cd/E23824_01/html/819-0690/chapter6-83432.html#scrolltoc typedef struct { Elf32_Word p_type; Elf32_Off p_offset; Elf32_Addr p_vaddr; Elf32_Addr p_paddr; Elf32_Word p_filesz; Elf32_Word p_memsz; Elf32_Word p_flags; Elf32_Word p_align; } Elf32_Phdr; typedef struct { Elf64_Word p_type; Elf64_Word p_flags; Elf64_Off p_offset; Elf64_Addr p_vaddr; Elf64_Addr p_paddr; Elf64_Xword p_filesz; Elf64_Xword p_memsz; Elf64_Xword p_align; } Elf64_Phdr; // ELF segment types #define PT_NULL 0 #define PT_LOAD 1 // Specifies a loadable segment #define PT_DYNAMIC 2 // Specifies dynamic linking information. #define PT_INTERP 3 // Specifies the location and size of a null-terminated path name to invoke as an interpreter #define PT_NOTE 4 // Specifies the location and size of auxiliary information #define PT_SHLIB 5 #define PT_PHDR 6 // Specifies the location and size of the program header table #define PT_TLS 7 // Specifies a thread-local storage template /* PT_LOOS - PT_HIOS Values in this inclusive range are reserved for OS-specific semantics. */ #define PT_LOOS 0x60000000 #define PT_SUNW_UNWIND 0x6464e550 #define PT_SUNW_EH_FRAME 0x6474e550 #define PT_LOSUNW 0x6ffffffa #define PT_SUNWBSS 0x6ffffffa #define PT_SUNWSTACK 0x6ffffffb #define PT_SUNWDTRACE 0x6ffffffc #define PT_SUNWCAP 0x6ffffffd #define PT_HISUNW 0x6fffffff #define PT_HIOS 0x6fffffff #define PT_LOPROC 0x70000000 #define PT_HIPROC 0x7fffffff // ELF Segment Flags #define PF_X 0x1 // Execute #define PF_W 0x2 // Write #define PF_R 0x4 // Read #define PF_MASKPROC 0xf0000000 // Unspecified // --> end ========== program header ========= /** * @brief 校验是否为ELF文件 * * @param ehdr */ bool elf_check(void * ehdr);