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我想知道二进制文本部分的确切字节位置，最好通过算法检查它。我试过使用size，但这似乎只给了我部分的大小，而不是它们的位置，我试过使用readelf，但坦率地说，这给了我太多信息。

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的输出readelf -S如下所示：

There are 21 section headers, starting at offset 0x1fcdc:

Section Headers:
  [Nr] Name              Type            Addr     Off    Size   ES Flg Lk Inf Al
  [ 0]                   NULL            00000000 000000 000000 00      0   0  0
  [ 1] .hash             HASH            000000b4 0000b4 0008e0 04   A  2   0  4
  [ 2] .dynsym           DYNSYM          00000994 000994 0012f0 10   A  3   3  4
  [ 3] .dynstr           STRTAB          00001c84 001c84 0016a4 00   A  0   0  1
  [ 4] .gnu.version      VERSYM          00003328 003328 00025e 02   A  2   0  2
  [ 5] .gnu.version_d    VERDEF          00003588 003588 000118 00   A  3  10  4
  [ 6] .gnu.version_r    VERNEED         000036a0 0036a0 000110 00   A  3   2  4
  [ 7] .rel.dyn          REL             000037b0 0037b0 001428 08   A  2   0  4
  [ 8] .rel.plt          REL             00004bd8 004bd8 0006e0 08   A  2   9  4
  [ 9] .plt              PROGBITS        000052b8 0052b8 000a64 04  AX  0   0  4
  [10] .text             PROGBITS        00005d1c 005d1c 0141d0 00  AX  0   0  4
  [11] .rodata           PROGBITS        00019eec 019eec 004121 00   A  0   0  4
  [12] .data.rel.ro      PROGBITS        0001f010 01e010 00119c 00  WA  0   0  4
  [13] .dynamic          DYNAMIC         000201ac 01f1ac 000110 08  WA  3   0  4
  [14] .got              PROGBITS        000202bc 01f2bc 00045c 04  WA  0   0  4
  [15] .data             PROGBITS        00020718 01f718 0002d0 00  WA  0   0  4
  [16] .bss              NOBITS          000209e8 01f9e8 0005d8 00  WA  0   0  4
  [17] .comment          PROGBITS        00000000 01f9e8 0001f8 00      0   0  1
  [18] .ARM.attributes   ARM_ATTRIBUTES  00000000 01fbe0 00002b 00      0   0  1
  [19] .gnu_debuglink    PROGBITS        00000000 01fc0b 000014 00      0   0  1
  [20] .shstrtab         STRTAB          00000000 01fc1f 0000ba 00      0   0  1
Key to Flags:
  W (write), A (alloc), X (execute), M (merge), S (strings)
  I (info), L (link order), G (group), T (TLS), E (exclude), x (unknown)
  O (extra OS processing required) o (OS specific), p (processor specific)

线[10]是.text截面。该Addr列给出了加载该节的虚拟地址，该Off列给出了文件内该节的偏移量，该Size列给出了该节的大小。所有数字均以十六进制表示。

elf.h以编程方式，您可以通过使用中定义的结构解析文件来获取有关任何部分的信息。这是一个示例（为简单起见，省略了错误检查和清理）：

int fd = open(..., O_RDONLY);

/* map ELF file into memory for easier manipulation */
struct stat statbuf;
fstat(fd, &statbuf);
char *fbase = mmap(NULL, statbuf.st_size, PROT_READ, MAP_SHARED, fd, 0);

Elf32_Ehdr *ehdr = (Elf32_Ehdr *)fbase;
Elf32_Shdr *sects = (Elf32_Shdr *)(fbase + ehdr->e_shoff);
int shsize = ehdr->e_shentsize;
int shnum = ehdr->e_shnum;
int shstrndx = ehdr->e_shstrndx;

/* get string table index */
Elf32_Shdr *shstrsect = &sects[shstrndx];
char *shstrtab = fbase + shstrsect->sh_offset;

int i;
for(i=0; i<shnum; i++) {
    if(!strcmp(shstrtab+sects[i].sh_name, ".text")) {
        /* found the text section: inspect sects[i].sh_offset, sects[i].sh_size */
    }
}
于 2013-08-24T13:00:48.340 回答