1 #pragma once
2 #include <common/glib.h>
3 
4 // --> begin ==============EHDR=====================
5 // Reference: https://docs.oracle.com/cd/E23824_01/html/819-0690/chapter6-43405.html#scrolltoc
6 
7 // ====== ELF32 Header中的数据类型定义 ====
8 typedef uint32_t Elf32_Addr;
9 typedef uint16_t Elf32_Half;
10 typedef uint32_t Elf32_Off;
11 typedef uint32_t Elf32_SWord;
12 typedef uint32_t Elf32_Word;
13 
14 // ====== ELF64 Header中的数据类型定义 ====
15 typedef uint64_t Elf64_Addr;
16 typedef uint16_t Elf64_Half;
17 typedef uint64_t Elf64_Off;
18 typedef uint32_t Elf64_Sword;
19 typedef uint32_t Elf64_Word;
20 typedef uint64_t Elf64_Xword;
21 typedef uint64_t Elf64_Sxword;
22 
23 // ====== ELF Identification Index ======
24 // Purpose: File identification
25 #define EI_MAG0 0
26 #define EI_MAG1 1
27 #define EI_MAG2 2
28 #define EI_MAG3 3
29 // Purpose: File class
30 #define EI_CLASS 4
31 // Purpose: Data encoding
32 #define EI_DATA 5
33 // Purpose: File version
34 #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
35 
36 // Purpose: Operating system/ABI identification
37 #define EI_OSABI 7 // e_ident[EI_OSABI]指定了操作系统以及对象所对应的ABI
38 
39 // Purpose: ABI version
40 #define EI_ABIVERSION 8 // e_ident[EI_ABIVERSION] 指定了对象所对应的ABI版本.
41 
42 // Purpose: Start of padding bytes
43 #define EI_PAD 9 // 这个值标志了e_ident中未使用字节的的起始下标
44 // Purpose: Size of e_ident[]
45 #define EI_NIDENT 16
46 
47 // EI_MAG0 - EI_MAG3 这是一个4byte的 magic number
48 #define ELFMAG0 0x7f
49 #define ELFMAG1 'E'
50 #define ELFMAG2 'L'
51 #define ELFMAG3 'F'
52 
53 // EI_CLASS  e_ident[EI_CLASS]指明了文件的类型或capacity
54 #define ELFCLASSNONE 0 // Invalid class
55 #define ELFCLASS32 1   // 32–bit objects
56 #define ELFCLASS64 2   // 64–bit objects
57 
58 // EI_DATA e_ident[EI_DATA]指明了与处理器相关的数据的编码方式
59 #define ELFDATANONE 0
60 #define ELFDATA2LSB 1 //  小端对齐
61 #define ELFDATA2MSB 2 // 大端对齐
62 
63 // ELF e_type的类型定义
64 #define ET_NONE 0        // No file type
65 #define ET_REL 1         // Relocatable file
66 #define ET_EXEC 2        // Executable file
67 #define ET_DYN 3         // Shared object file
68 #define ET_CORE 4        // Core file
69 #define ET_LOPROC 0xff00 // Processor-specific
70 #define ET_HIPROC 0xffff // Processor-specific
71 
72 // e_machine的类型定义
73 #define EM_NONE 0         // No machine
74 #define EM_SPARC 2        // SPARC
75 #define EM_386 3          // Intel 80386
76 #define EM_SPARC32PLUS 18 // Sun SPARC 32+
77 #define EM_SPARCV9 43     // SPARC V9
78 #define EM_AMD64 62       // AMD 64
79 
80 // e_version的类型定义
81 #define EV_NONE 0 // Invalid Version
82 // EV_CURRENT: Value>=1 means current version
83 
84 // e_flags 定义
85 // e_flags for SPARC
86 #define EF_SPARC_EXT_MASK 0xffff00 // Vendor Extension mask
87 #define EF_SPARC_32PLUS 0x000100   // Generic V8+ features
88 #define EF_SPARC_SUN_US1 0x000200  // Sun UltraSPARC 1 Extensions
89 #define EF_SPARC_HAL_R1 0x000400   // HAL R1 Extensions
90 #define EF_SPARC_SUN_US3 0x000800  // Sun UltraSPARC 3 Extensions
91 #define EF_SPARCV9_MM 0x3          // Mask for Memory Model
92 #define EF_SPARCV9_TSO 0x0         // Total Store Ordering
93 #define EF_SPARCV9_PSO 0x1         // Partial Store Ordering
94 #define EF_SPARCV9_RMO 0x2         // Relaxed Memory Ordering
95 
96 #define PN_XNUM 0xffff
97 
98 typedef struct
99 {
100     unsigned char e_ident[EI_NIDENT];
101     Elf32_Half e_type;
102     Elf32_Half e_machine;
103     Elf32_Word e_version;
104     Elf32_Addr e_entry;
105     Elf32_Off e_phoff;
106     Elf32_Off e_shoff;
107     Elf32_Word e_flags;
108     Elf32_Half e_ehsize;
109     Elf32_Half e_phentsize;
110     Elf32_Half e_phnum;
111     Elf32_Half e_shentsize;
112     Elf32_Half e_shnum;
113     Elf32_Half e_shstrndx;
114 } Elf32_Ehdr;
115 
116 typedef struct
117 {
118     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
119     Elf64_Half e_type;                // 文件类型标志符
120     Elf64_Half e_machine;             // 该文件依赖的处理器架构类型
121     Elf64_Word e_version;             // 对象文件的版本
122     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
123     Elf64_Off e_phoff;                // The program header table's file offset in bytes. 若没有,则为0
124     Elf64_Off e_shoff;                // The section header table's file offset in bytes. 若没有,则为0
125     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
126     Elf64_Half e_ehsize;              // ELF Header的大小(单位:字节)
127     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)
128     Elf64_Half e_phnum;               // program header table的entry数量
129                                       // e_phentsize*e_phnum=program header table的大小
130                                       // 如果没有program header table,该值为0
131                                       // 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)
132                                       //  其他情况下,第一个section header entry的sh_info的值为0
133 
134     Elf64_Half e_shentsize; // 每个section header的大小(字节
135                             // 每个section header是section header table的一个entry
136 
137     Elf64_Half e_shnum; // section header table的entry数量
138                         // e_shentsize*e_shnum=section header table的大小
139                         // 如果没有section header table,那么该值为0
140                         // 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
141                         // section header at index 0的sh_size变量中,否则第一个sh_size为0
142 
143     Elf64_Half e_shstrndx; // 与section name string表相关联的section header table的entry的索引下标
144                            // 如果没有name string table,那么该值等于SHN_UNDEF
145                            // 如果对应的index>=SHN_LORESERVE(0xff00), 那么该变量值为SHN_XINDEX(0xffff)
146                            // 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
147                            // 否则初始section header entry的sh_link变量为0
148 } Elf64_Ehdr;
149 
150 // --> end ==============EHDR=====================
151 
152 // --> begin ==============SHDR=====================
153 
154 // reference: https://docs.oracle.com/cd/E23824_01/html/819-0690/chapter6-94076.html#scrolltoc
155 
156 // ===== ELF Special Section Indexes =====
157 #define SHN_UNDEF 0          // An undefined, missing, irrelevant, or otherwise meaningless section reference.
158 #define SHN_LORESERVE 0xff00 // The lower boundary of the range of reserved indexes.
159                              // The system reserves indexes between SHN_LORESERVE and SHN_HIRESERVE, inclusive.
160 #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
161 #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
162 #define SHN_AFTER 0xff01
163 #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.
164 #define SHN_HIPROC 0xff1f
165 #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
166 #define SHN_LOSUNW 0xff3f      // SHN_LOSUNW - SHN_HISUNW Values in this inclusive range are reserved for Sun-specific semantics.
167 #define SHN_SUNW_IGNORE 0xff3f // This section index provides a temporary symbol definition within relocatable objects. Reserved for internal use by dtrace(1M).
168 #define SHN_HISUNW 0xff3f
169 #define SHN_HIOS 0xff3f
170 #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.
171 #define SHN_COMMON 0xfff2 // Symbols defined relative to this section are common symbols
172 #define SHN_XINDEX 0xffff
173 #define SHN_HIRESERVE 0xffff // The upper boundary of the range of reserved indexes.
174 /*
175 Note -
176     Although index 0 is reserved as the undefined value,
177     the section header table contains an entry for index 0.
178     That is, if the e_shnum member of the ELF header indicates
179     a file has 6 entries in the section header table, the sections
180     have the indexes 0 through 5. The contents of the initial entry
181     are specified later in this section.
182 */
183 
184 typedef struct
185 {
186     Elf32_Word sh_name;
187     Elf32_Word sh_type;
188     Elf32_Word sh_flags;
189     Elf32_Addr sh_addr;
190     Elf32_Off sh_offset;
191     Elf32_Word sh_size;
192     Elf32_Word sh_link;
193     Elf32_Word sh_info;
194     Elf32_Word sh_addralign;
195     Elf32_Word sh_entsize;
196 } Elf32_Shdr;
197 
198 typedef struct
199 {
200     Elf64_Word sh_name; // 段名
201     Elf64_Word sh_type; // 段的类型(按照内容和语义来分类)
202     Elf64_Xword sh_flags;
203     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
204     Elf64_Off sh_offset;      // The byte offset from the beginning of the file to the first byte in the section
205                               // 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
206     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)
207     Elf64_Word sh_link;       // A section header table index link, whose interpretation depends on the section type.
208     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.
209     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。
210     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
211 } Elf64_Shdr;
212 
213 // ELF Section Types, sh_type
214 #define SHT_NULL 0
215 #define SHT_PROGBITS 1
216 #define SHT_SYMTAB 2 // Identifies a symbol table
217 #define SHT_STRTAB 3 // Identifies a string table.
218 #define SHT_RELA 4
219 #define SHT_HASH 5
220 #define SHT_DYNAMIC 6
221 #define SHT_NOTE 7
222 #define SHT_NOBITS 8
223 #define SHT_REL 9
224 #define SHT_SHLIB 10
225 #define SHT_DYNSYM 11 // Identifies a symbol table
226 #define SHT_INIT_ARRAY 14
227 #define SHT_FINI_ARRAY 15
228 #define SHT_PREINIT_ARRAY 16
229 #define SHT_GROUP 17
230 #define SHT_SYMTAB_SHNDX 18
231 #define SHT_LOOS 0x60000000
232 #define SHT_LOSUNW 0x6fffffef
233 #define SHT_SUNW_capchain 0x6fffffef
234 #define SHT_SUNW_capinfo 0x6ffffff0
235 #define SHT_SUNW_symsort 0x6ffffff1
236 #define SHT_SUNW_tlssort 0x6ffffff2
237 #define SHT_SUNW_LDYNSYM 0x6ffffff3 // Identifies a symbol table
238 #define SHT_SUNW_dof 0x6ffffff4
239 #define SHT_SUNW_cap 0x6ffffff5
240 #define SHT_SUNW_SIGNATURE 0x6ffffff6
241 #define SHT_SUNW_ANNOTATE 0x6ffffff7
242 #define SHT_SUNW_DEBUGSTR 0x6ffffff8
243 #define SHT_SUNW_DEBUG 0x6ffffff9
244 #define SHT_SUNW_move 0x6ffffffa
245 #define SHT_SUNW_COMDAT 0x6ffffffb
246 #define SHT_SUNW_syminfo 0x6ffffffc
247 #define SHT_SUNW_verdef 0x6ffffffd
248 #define SHT_SUNW_verneed 0x6ffffffe
249 #define SHT_SUNW_versym 0x6fffffff
250 #define SHT_HISUNW 0x6fffffff
251 #define SHT_HIOS 0x6fffffff
252 #define SHT_LOPROC 0x70000000
253 #define SHT_SPARC_GOTDATA 0x70000000
254 #define SHT_AMD64_UNWIND 0x70000001
255 #define SHT_HIPROC 0x7fffffff
256 #define SHT_LOUSER 0x80000000
257 #define SHT_HIUSER 0xffffffff
258 
259 // ELF Section Attribute Flags
260 #define SHF_WRITE 0x1     // Identifies a section that should be writable during process execution
261 #define SHF_ALLOC 0x2     // Identifies a section that occupies memory during process execution
262 #define SHF_EXECINSTR 0x4 // contains executable machine instructions
263 #define SHF_MERGE 0x10
264 #define SHF_STRINGS 0x20
265 #define SHF_INFO_LINK 0x40  // This section headers sh_info field holds a section header table index
266 #define SHF_LINK_ORDER 0x80 // This section adds special ordering requirements to the link-editor
267 #define SHF_OS_NONCONFORMING 0x100
268 #define SHF_GROUP 0x200
269 #define SHF_TLS 0x400
270 #define SHF_MASKOS 0x0ff00000
271 #define SHF_AMD64_LARGE 0x10000000 // identifies a section that can hold more than 2 Gbyte
272 #define SHF_ORDERED 0x40000000
273 #define SHF_EXCLUDE 0x80000000
274 #define SHF_MASKPROC 0xf0000000
275 
276 // --> end ==============SHDR=====================
277 
278 // --> begin ========== symbol table section ======
279 typedef struct
280 {
281     Elf32_Word st_name;
282     Elf32_Addr st_value;
283     Elf32_Word st_size;
284     unsigned char st_info;
285     unsigned char st_other;
286     Elf32_Half st_shndx;
287 } Elf32_Sym;
288 typedef struct
289 {
290     Elf64_Word st_name;
291     unsigned char st_info;
292     unsigned char st_other;
293     Elf64_Half st_shndx;
294     Elf64_Addr st_value;
295     Elf64_Xword st_size;
296 } Elf64_Sym;
297 
298 // --> end ========== symbol table section ======
299 
300 // --> begin ========== program header =========
301 // Ref: https://docs.oracle.com/cd/E23824_01/html/819-0690/chapter6-83432.html#scrolltoc
302 
303 typedef struct
304 {
305     Elf32_Word p_type;
306     Elf32_Off p_offset;
307     Elf32_Addr p_vaddr;
308     Elf32_Addr p_paddr;
309     Elf32_Word p_filesz;
310     Elf32_Word p_memsz;
311     Elf32_Word p_flags;
312     Elf32_Word p_align;
313 } Elf32_Phdr;
314 
315 typedef struct
316 {
317     Elf64_Word p_type;
318     Elf64_Word p_flags;
319     Elf64_Off p_offset;
320     Elf64_Addr p_vaddr;
321     Elf64_Addr p_paddr;
322     Elf64_Xword p_filesz;
323     Elf64_Xword p_memsz;
324     Elf64_Xword p_align;
325 } Elf64_Phdr;
326 
327 // ELF segment types
328 #define PT_NULL 0
329 #define PT_LOAD 1    // Specifies a loadable segment
330 #define PT_DYNAMIC 2 // Specifies dynamic linking information.
331 #define PT_INTERP 3  // Specifies the location and size of a null-terminated path name to invoke as an interpreter
332 #define PT_NOTE 4    // Specifies the location and size of auxiliary information
333 #define PT_SHLIB 5
334 #define PT_PHDR 6 // Specifies the location and size of the program header table
335 #define PT_TLS 7  // Specifies a thread-local storage template
336 /*
337 PT_LOOS - PT_HIOS
338 Values in this inclusive range are reserved for OS-specific semantics.
339 */
340 #define PT_LOOS 0x60000000
341 #define PT_SUNW_UNWIND 0x6464e550
342 #define PT_SUNW_EH_FRAME 0x6474e550
343 #define PT_LOSUNW 0x6ffffffa
344 #define PT_SUNWBSS 0x6ffffffa
345 #define PT_SUNWSTACK 0x6ffffffb
346 #define PT_SUNWDTRACE 0x6ffffffc
347 #define PT_SUNWCAP 0x6ffffffd
348 #define PT_HISUNW 0x6fffffff
349 #define PT_HIOS 0x6fffffff
350 #define PT_LOPROC 0x70000000
351 #define PT_HIPROC 0x7fffffff
352 
353 //  ELF Segment Flags
354 #define PF_X 0x1               // Execute
355 #define PF_W 0x2               // Write
356 #define PF_R 0x4               // Read
357 #define PF_MASKPROC 0xf0000000 // Unspecified
358 
359 
360 // --> end ========== program header =========
361 
362 /**
363  * @brief 校验是否为ELF文件
364  *
365  * @param ehdr
366  */
367 bool elf_check(void * ehdr);