readelf: GNU-style options

This commit is contained in:
K. Lange 2021-08-28 15:29:18 +09:00
parent 56eff9a3e2
commit 9e018d2932

View File

@ -8,8 +8,15 @@
#include <string.h> #include <string.h>
#include <stdlib.h> #include <stdlib.h>
#include <errno.h> #include <errno.h>
#include <getopt.h>
#include <kernel/elf.h> #include <kernel/elf.h>
#define SHOW_FILE_HEADER 0x0001
#define SHOW_SECTION_HEADERS 0x0002
#define SHOW_PROGRAM_HEADERS 0x0004
#define SHOW_SYMBOLS 0x0008
#define SHOW_DYNAMIC 0x0010
#define SHOW_RELOCATIONS 0x0020
static const char * elf_classToStr(unsigned char ei_class) { static const char * elf_classToStr(unsigned char ei_class) {
static char buf[64]; static char buf[64];
@ -391,298 +398,397 @@ static char * symbolBindToStr(int bind) {
} }
} }
static int usage(char * argv[]) {
fprintf(stderr,
"Usage: %s <option(s)> elf-file(s)\n"
" Displays information about ELF object files in a GNU binutils-compatible way.\n"
" Supported options:\n"
" -a --all Equivalent to -h -l -S -s -d -r\n"
" -h --file-header Display the ELF file header\n"
" -l --program-headers Display the program headers\n"
" -S --section-headers Display the section headers\n"
" -h --headers Equivalent to -h -l -S\n"
" -s --syms Display symbol able\n"
" -d --dynamic Display dynamic section\n"
" -r --relocs Display relocations\n"
" -H --help Show this help text\n"
" Aliases:\n"
" --segments Same as --file-header\n"
" --sections Same as --section-headers\n"
" --symbols Same as --syms\n"
, argv[0]);
return 1;
}
int main(int argc, char * argv[]) { int main(int argc, char * argv[]) {
if (argc < 2) {
fprintf(stderr, "%s: expected filename\n", argv[0]); static struct option long_opts[] = {
return 1; {"all", no_argument, 0, 'a'},
{"file-header", no_argument, 0, 'h'},
{"program-headers", no_argument, 0, 'l'},
{"section-headers", no_argument, 0, 'S'},
{"headers", no_argument, 0, 'e'},
{"syms", no_argument, 0, 's'},
{"dynamic", no_argument, 0, 'd'},
{"relocs", no_argument, 0, 'r'},
{"help", no_argument, 0, 'H'},
{"segments", no_argument, 0, 'l'}, /* Alias for --program-headers */
{"sections", no_argument, 0, 'S'}, /* Alias for --section-headers */
{"symbols", no_argument, 0, 's'}, /* Alias for --syms */
{0,0,0,0}
};
int show_bits = 0;
int index, c;
while ((c = getopt_long(argc, argv, "ahlSesdrH", long_opts, &index)) != -1) {
if (!c) {
if (long_opts[index].flag == 0) {
c = long_opts[index].val;
}
}
switch (c) {
case 'H':
return usage(argv);
case 'a':
show_bits |= SHOW_FILE_HEADER | SHOW_SECTION_HEADERS | SHOW_PROGRAM_HEADERS | SHOW_SYMBOLS | SHOW_DYNAMIC | SHOW_RELOCATIONS;
break;
case 'h':
show_bits |= SHOW_FILE_HEADER;
break;
case 'l':
show_bits |= SHOW_PROGRAM_HEADERS;
break;
case 'S':
show_bits |= SHOW_SECTION_HEADERS;
break;
case 'e':
show_bits |= SHOW_FILE_HEADER | SHOW_PROGRAM_HEADERS | SHOW_SECTION_HEADERS;
break;
case 's':
show_bits |= SHOW_SYMBOLS;
break;
case 'r':
show_bits |= SHOW_RELOCATIONS;
break;
default:
fprintf(stderr, "Unrecognized option: %c\n", c);
break;
}
} }
FILE * f = fopen(argv[1],"r"); if (optind >= argc || !show_bits) {
return usage(argv);
if (!f) {
fprintf(stderr, "%s: %s: %s\n", argv[0], argv[1], strerror(errno));
return 1;
} }
/** int out = 0;
* Validate header. int print_names = 0;
*/
Elf64_Header header;
fread(&header, sizeof(Elf64_Header), 1, f);
if (memcmp("\x7F" "ELF",&header,4)) { if (optind + 1 < argc) {
fprintf(stderr, "%s: %s: not an elf\n", argv[0], argv[1]); print_names = 1;
return 1;
} }
printf("ELF Header:\n"); for (; optind < argc; optind++) {
printf(" Magic: %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x\n", FILE * f = fopen(argv[optind],"r");
header.e_ident[0], header.e_ident[1], header.e_ident[2], header.e_ident[3],
header.e_ident[4], header.e_ident[5], header.e_ident[6], header.e_ident[7],
header.e_ident[8], header.e_ident[9], header.e_ident[10], header.e_ident[11],
header.e_ident[12], header.e_ident[13], header.e_ident[14], header.e_ident[15]);
printf(" Class: %s\n", elf_classToStr(header.e_ident[EI_CLASS]));
printf(" Data: %s\n", elf_dataToStr(header.e_ident[EI_DATA]));
printf(" Version: %s\n", elf_versionToStr(header.e_ident[EI_VERSION]));
printf(" OS/ABI: %s\n", elf_osabiToStr(header.e_ident[EI_OSABI]));
printf(" ABI Version: %u\n", header.e_ident[EI_ABIVERSION]);
if (header.e_ident[EI_CLASS] != ELFCLASS64) { if (!f) {
return 0; fprintf(stderr, "%s: %s: %s\n", argv[0], argv[optind], strerror(errno));
} out = 1;
continue;
}
/* Byte-order dependent from here on out... */ if (print_names) {
printf(" Type: %s\n", elf_typeToStr(header.e_type)); printf("\nFile: %s\n", argv[optind]);
printf(" Machine: %s\n", elf_machineToStr(header.e_machine)); }
printf(" Version: 0x%x\n", header.e_version);
printf(" Entry point address: 0x%lx\n", header.e_entry);
printf(" Start of program headers: %lu (bytes into file)\n", header.e_phoff);
printf(" Start of section headers: %lu (bytes into file)\n", header.e_shoff);
printf(" Flags: 0x%x\n", header.e_flags);
printf(" Size of this header: %u (bytes)\n", header.e_ehsize);
printf(" Size of program headers: %u (bytes)\n", header.e_phentsize);
printf(" Number of program headers: %u\n", header.e_phnum);
printf(" Size of section headers: %u (bytes)\n", header.e_shentsize);
printf(" Number of section headers: %u\n", header.e_shnum);
printf(" Section header string table index: %u\n", header.e_shstrndx);
/* Get the section header string table */ /**
Elf64_Shdr shstr_hdr; * Validate header.
fseek(f, header.e_shoff + header.e_shentsize * header.e_shstrndx, SEEK_SET); */
fread(&shstr_hdr, sizeof(Elf64_Shdr), 1, f); Elf64_Header header;
fread(&header, sizeof(Elf64_Header), 1, f);
char * stringTable = malloc(shstr_hdr.sh_size); if (memcmp("\x7F" "ELF",&header,4)) {
fseek(f, shstr_hdr.sh_offset, SEEK_SET); fprintf(stderr, "%s: %s: not an elf\n", argv[0], argv[optind]);
fread(stringTable, shstr_hdr.sh_size, 1, f); out = 1;
continue;
}
/** if (show_bits & SHOW_FILE_HEADER) {
* Section Headers printf("ELF Header:\n");
*/ printf(" Magic: %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x\n",
printf("\nSection Headers:\n"); header.e_ident[0], header.e_ident[1], header.e_ident[2], header.e_ident[3],
printf(" [Nr] Name Type Address Offset\n"); header.e_ident[4], header.e_ident[5], header.e_ident[6], header.e_ident[7],
printf(" Size EntSize Flags Link Info Align\n"); header.e_ident[8], header.e_ident[9], header.e_ident[10], header.e_ident[11],
for (unsigned int i = 0; i < header.e_shnum; ++i) { header.e_ident[12], header.e_ident[13], header.e_ident[14], header.e_ident[15]);
fseek(f, header.e_shoff + header.e_shentsize * i, SEEK_SET); printf(" Class: %s\n", elf_classToStr(header.e_ident[EI_CLASS]));
Elf64_Shdr sectionHeader; printf(" Data: %s\n", elf_dataToStr(header.e_ident[EI_DATA]));
fread(&sectionHeader, sizeof(Elf64_Shdr), 1, f); printf(" Version: %s\n", elf_versionToStr(header.e_ident[EI_VERSION]));
printf(" OS/ABI: %s\n", elf_osabiToStr(header.e_ident[EI_OSABI]));
printf(" ABI Version: %u\n", header.e_ident[EI_ABIVERSION]);
}
printf(" [%2d] %-17.17s %-16.16s %016lx %08lx\n", if (header.e_ident[EI_CLASS] != ELFCLASS64) {
i, stringTable + sectionHeader.sh_name, sectionHeaderTypeToStr(sectionHeader.sh_type), continue;
sectionHeader.sh_addr, sectionHeader.sh_offset); }
printf(" %016lx %016lx %4ld %6d %5d %5ld\n",
sectionHeader.sh_size, sectionHeader.sh_entsize, sectionHeader.sh_flags,
sectionHeader.sh_link, sectionHeader.sh_info, sectionHeader.sh_addralign);
}
/** if (show_bits & SHOW_FILE_HEADER) {
* Program Headers /* Byte-order dependent from here on out... */
*/ printf(" Type: %s\n", elf_typeToStr(header.e_type));
if (header.e_phoff && header.e_phnum) { printf(" Machine: %s\n", elf_machineToStr(header.e_machine));
printf("\nProgram Headers:\n"); printf(" Version: 0x%x\n", header.e_version);
printf(" Type Offset VirtAddr PhysAddr\n"); printf(" Entry point address: 0x%lx\n", header.e_entry);
printf(" FileSiz MemSiz Flags Align\n"); printf(" Start of program headers: %lu (bytes into file)\n", header.e_phoff);
for (unsigned int i = 0; i < header.e_phnum; ++i) { printf(" Start of section headers: %lu (bytes into file)\n", header.e_shoff);
fseek(f, header.e_phoff + header.e_phentsize * i, SEEK_SET); printf(" Flags: 0x%x\n", header.e_flags);
Elf64_Phdr programHeader; printf(" Size of this header: %u (bytes)\n", header.e_ehsize);
fread(&programHeader, sizeof(Elf64_Phdr), 1, f); printf(" Size of program headers: %u (bytes)\n", header.e_phentsize);
printf(" Number of program headers: %u\n", header.e_phnum);
printf(" Size of section headers: %u (bytes)\n", header.e_shentsize);
printf(" Number of section headers: %u\n", header.e_shnum);
printf(" Section header string table index: %u\n", header.e_shstrndx);
}
printf(" %-14.14s 0x%016lx 0x%016lx 0x%016lx\n", /* Get the section header string table */
programHeaderTypeToStr(programHeader.p_type), Elf64_Shdr shstr_hdr;
programHeader.p_offset, programHeader.p_vaddr, programHeader.p_paddr); fseek(f, header.e_shoff + header.e_shentsize * header.e_shstrndx, SEEK_SET);
printf(" 0x%016lx 0x%016lx %s 0x%lx\n", fread(&shstr_hdr, sizeof(Elf64_Shdr), 1, f);
programHeader.p_filesz, programHeader.p_memsz,
programHeaderFlagsToStr(programHeader.p_flags), programHeader.p_align); char * stringTable = malloc(shstr_hdr.sh_size);
fseek(f, shstr_hdr.sh_offset, SEEK_SET);
fread(stringTable, shstr_hdr.sh_size, 1, f);
/**
* Section Headers
*/
if (show_bits & SHOW_SECTION_HEADERS) {
printf("\nSection Headers:\n");
printf(" [Nr] Name Type Address Offset\n");
printf(" Size EntSize Flags Link Info Align\n");
for (unsigned int i = 0; i < header.e_shnum; ++i) {
fseek(f, header.e_shoff + header.e_shentsize * i, SEEK_SET);
Elf64_Shdr sectionHeader;
fread(&sectionHeader, sizeof(Elf64_Shdr), 1, f);
printf(" [%2d] %-17.17s %-16.16s %016lx %08lx\n",
i, stringTable + sectionHeader.sh_name, sectionHeaderTypeToStr(sectionHeader.sh_type),
sectionHeader.sh_addr, sectionHeader.sh_offset);
printf(" %016lx %016lx %4ld %6d %5d %5ld\n",
sectionHeader.sh_size, sectionHeader.sh_entsize, sectionHeader.sh_flags,
sectionHeader.sh_link, sectionHeader.sh_info, sectionHeader.sh_addralign);
}
}
/**
* Program Headers
*/
if (show_bits & SHOW_PROGRAM_HEADERS && header.e_phoff && header.e_phnum) {
printf("\nProgram Headers:\n");
printf(" Type Offset VirtAddr PhysAddr\n");
printf(" FileSiz MemSiz Flags Align\n");
for (unsigned int i = 0; i < header.e_phnum; ++i) {
fseek(f, header.e_phoff + header.e_phentsize * i, SEEK_SET);
Elf64_Phdr programHeader;
fread(&programHeader, sizeof(Elf64_Phdr), 1, f);
printf(" %-14.14s 0x%016lx 0x%016lx 0x%016lx\n",
programHeaderTypeToStr(programHeader.p_type),
programHeader.p_offset, programHeader.p_vaddr, programHeader.p_paddr);
printf(" 0x%016lx 0x%016lx %s 0x%lx\n",
programHeader.p_filesz, programHeader.p_memsz,
programHeaderFlagsToStr(programHeader.p_flags), programHeader.p_align);
if (programHeader.p_type == PT_INTERP) {
/* Read interpreter string */
char * tmp = malloc(programHeader.p_filesz);
fseek(f, programHeader.p_offset, SEEK_SET);
fread(tmp, programHeader.p_filesz, 1, f);
printf(" [Requesting program interpreter: %.*s]\n",
(int)programHeader.p_filesz, tmp);
free(tmp);
}
}
}
/* TODO Section to segment mapping? */
/**
* Dump section information.
*/
for (unsigned int i = 0; i < header.e_shnum; ++i) {
fseek(f, header.e_shoff + header.e_shentsize * i, SEEK_SET);
Elf64_Shdr sectionHeader;
fread(&sectionHeader, sizeof(Elf64_Shdr), 1, f);
/* I think there should only be one of these... */
switch (sectionHeader.sh_type) {
case SHT_DYNAMIC:
if (show_bits & SHOW_DYNAMIC) {
printf("\nDynamic section at offset 0x%lx contains (up to) %ld entries:\n",
sectionHeader.sh_offset, sectionHeader.sh_size / sectionHeader.sh_entsize);
printf(" Tag Type Name/Value\n");
/* Read the linked string table */
Elf64_Shdr dynstr;
fseek(f, header.e_shoff + header.e_shentsize * sectionHeader.sh_link, SEEK_SET);
fread(&dynstr, sizeof(Elf64_Shdr), 1, f);
char * dynStr = malloc(dynstr.sh_size);
fseek(f, dynstr.sh_offset, SEEK_SET);
fread(dynStr, dynstr.sh_size, 1, f);
char * dynTable = malloc(sectionHeader.sh_size);
fseek(f, sectionHeader.sh_offset, SEEK_SET);
fread(dynTable, sectionHeader.sh_size, 1, f);
for (unsigned int i = 0; i < sectionHeader.sh_size / sectionHeader.sh_entsize; i++) {
Elf64_Dyn * dynEntry = (Elf64_Dyn *)(dynTable + sectionHeader.sh_entsize * i);
printf(" 0x%016lx %s\n",
dynEntry->d_tag,
dynamicTagToStr(dynEntry, dynStr));
if (dynEntry->d_tag == DT_NULL) break;
}
free(dynStr);
free(dynTable);
}
break;
case SHT_RELA:
if (show_bits & SHOW_RELOCATIONS) {
printf("\nRelocation section '%s' at offset 0x%lx contains %ld entries.\n",
stringTable + sectionHeader.sh_name, sectionHeader.sh_offset,
sectionHeader.sh_size / sizeof(Elf64_Rela));
printf(" Offset Info Type Sym. Value Sym. Name + Addend\n");
/* Section this relocation is in */
Elf64_Shdr shdr_this;
fseek(f, header.e_shoff + header.e_shentsize * sectionHeader.sh_info, SEEK_SET);
fread(&shdr_this, sizeof(Elf64_Shdr), 1, f);
/* Symbol table link */
Elf64_Shdr shdr_symtab;
fseek(f, header.e_shoff + header.e_shentsize * sectionHeader.sh_link, SEEK_SET);
fread(&shdr_symtab, sizeof(Elf64_Shdr), 1, f);
Elf64_Sym * symtab = malloc(shdr_symtab.sh_size);
fseek(f, shdr_symtab.sh_offset, SEEK_SET);
fread(symtab, shdr_symtab.sh_size, 1, f);
/* Symbol table's string table link */
Elf64_Shdr shdr_strtab;
fseek(f, header.e_shoff + header.e_shentsize * shdr_symtab.sh_link, SEEK_SET);
fread(&shdr_strtab, sizeof(Elf64_Shdr), 1, f);
char * strtab = malloc(shdr_strtab.sh_size);
fseek(f, shdr_strtab.sh_offset, SEEK_SET);
fread(strtab, shdr_strtab.sh_size, 1, f);
/* Load relocations from file */
Elf64_Rela * relocations = malloc(sectionHeader.sh_size);
fseek(f, sectionHeader.sh_offset, SEEK_SET);
fread((void*)relocations, sectionHeader.sh_size, 1, f);
for (unsigned int i = 0; i < sectionHeader.sh_size / sizeof(Elf64_Rela); ++i) {
Elf64_Shdr shdr;
Elf64_Sym * this = &symtab[ELF64_R_SYM(relocations[i].r_info)];
char * symName;
/* Get symbol name for this relocation */
if ((this->st_info & 0xF) == STT_SECTION) {
fseek(f, header.e_shoff + header.e_shentsize * this->st_shndx, SEEK_SET);
fread(&shdr, sizeof(Elf64_Shdr), 1, f);
symName = stringTable + shdr.sh_name;
} else {
symName = strtab + this->st_name;
}
/* Get the value currently in the section data */
Elf64_Xword value = 0;
int valueSize = sizeOfRelocationValue(ELF64_R_TYPE(relocations[i].r_info));
fseek(f, shdr_this.sh_offset + relocations[i].r_offset, SEEK_SET);
switch (valueSize) {
case 8:
{
uint64_t val;
fread(&val, valueSize, 1, f);
value = val;
break;
}
case 4:
{
uint32_t val;
fread(&val, valueSize, 1, f);
value = val;
break;
}
case 2:
{
uint16_t val;
fread(&val, valueSize, 1, f);
value = val;
break;
}
case 1:
{
uint8_t val;
fread(&val, valueSize, 1, f);
value = val;
break;
}
default:
break;
}
printf("%012lx %012lx %-15.15s %016lx %s + %lx\n",
relocations[i].r_offset, relocations[i].r_info,
relocationInfoToStr(ELF64_R_TYPE(relocations[i].r_info)),
value,
symName,
relocations[i].r_addend);
}
free(relocations);
free(strtab);
free(symtab);
}
break;
case SHT_SYMTAB:
if (show_bits & SHOW_SYMBOLS) {
printf("\nSymbol table '%s' contains %ld entries.\n",
stringTable + sectionHeader.sh_name,
sectionHeader.sh_size / sizeof(Elf64_Sym));
printf(" Num: Value Size Type Bind Vis Ndx Name\n");
Elf64_Sym * symtab = malloc(sectionHeader.sh_size);
fseek(f, sectionHeader.sh_offset, SEEK_SET);
fread(symtab, sectionHeader.sh_size, 1, f);
Elf64_Shdr shdr_strtab;
fseek(f, header.e_shoff + header.e_shentsize * sectionHeader.sh_link, SEEK_SET);
fread(&shdr_strtab, sizeof(Elf64_Shdr), 1, f);
char * strtab = malloc(shdr_strtab.sh_size);
fseek(f, shdr_strtab.sh_offset, SEEK_SET);
fread(strtab, shdr_strtab.sh_size, 1, f);
for (unsigned int i = 0; i < sectionHeader.sh_size / sizeof(Elf64_Sym); ++i) {
printf("%6u: %016lx %6lu %-7.7s %-6.6s %-4d %6d %s\n",
i, symtab[i].st_value, symtab[i].st_size,
symbolTypeToStr(symtab[i].st_info & 0xF),
symbolBindToStr(symtab[i].st_info >> 4),
symtab[i].st_other,
symtab[i].st_shndx,
strtab + symtab[i].st_name);
}
free(strtab);
free(symtab);
}
break;
default:
break;
if (programHeader.p_type == PT_INTERP) {
/* Read interpreter string */
char * tmp = malloc(programHeader.p_filesz);
fseek(f, programHeader.p_offset, SEEK_SET);
fread(tmp, programHeader.p_filesz, 1, f);
printf(" [Requesting program interpreter: %.*s]\n",
(int)programHeader.p_filesz, tmp);
free(tmp);
} }
} }
} }
/* TODO Section to segment mapping? */ return out;
/**
* Dump section information.
*/
for (unsigned int i = 0; i < header.e_shnum; ++i) {
fseek(f, header.e_shoff + header.e_shentsize * i, SEEK_SET);
Elf64_Shdr sectionHeader;
fread(&sectionHeader, sizeof(Elf64_Shdr), 1, f);
/* I think there should only be one of these... */
switch (sectionHeader.sh_type) {
case SHT_DYNAMIC:
{
printf("\nDynamic section at offset 0x%lx contains (up to) %ld entries:\n",
sectionHeader.sh_offset, sectionHeader.sh_size / sectionHeader.sh_entsize);
printf(" Tag Type Name/Value\n");
/* Read the linked string table */
Elf64_Shdr dynstr;
fseek(f, header.e_shoff + header.e_shentsize * sectionHeader.sh_link, SEEK_SET);
fread(&dynstr, sizeof(Elf64_Shdr), 1, f);
char * dynStr = malloc(dynstr.sh_size);
fseek(f, dynstr.sh_offset, SEEK_SET);
fread(dynStr, dynstr.sh_size, 1, f);
char * dynTable = malloc(sectionHeader.sh_size);
fseek(f, sectionHeader.sh_offset, SEEK_SET);
fread(dynTable, sectionHeader.sh_size, 1, f);
for (unsigned int i = 0; i < sectionHeader.sh_size / sectionHeader.sh_entsize; i++) {
Elf64_Dyn * dynEntry = (Elf64_Dyn *)(dynTable + sectionHeader.sh_entsize * i);
printf(" 0x%016lx %s\n",
dynEntry->d_tag,
dynamicTagToStr(dynEntry, dynStr));
if (dynEntry->d_tag == DT_NULL) break;
}
free(dynStr);
free(dynTable);
}
break;
case SHT_RELA:
{
printf("\nRelocation section '%s' at offset 0x%lx contains %ld entries.\n",
stringTable + sectionHeader.sh_name, sectionHeader.sh_offset,
sectionHeader.sh_size / sizeof(Elf64_Rela));
printf(" Offset Info Type Sym. Value Sym. Name + Addend\n");
/* Section this relocation is in */
Elf64_Shdr shdr_this;
fseek(f, header.e_shoff + header.e_shentsize * sectionHeader.sh_info, SEEK_SET);
fread(&shdr_this, sizeof(Elf64_Shdr), 1, f);
/* Symbol table link */
Elf64_Shdr shdr_symtab;
fseek(f, header.e_shoff + header.e_shentsize * sectionHeader.sh_link, SEEK_SET);
fread(&shdr_symtab, sizeof(Elf64_Shdr), 1, f);
Elf64_Sym * symtab = malloc(shdr_symtab.sh_size);
fseek(f, shdr_symtab.sh_offset, SEEK_SET);
fread(symtab, shdr_symtab.sh_size, 1, f);
/* Symbol table's string table link */
Elf64_Shdr shdr_strtab;
fseek(f, header.e_shoff + header.e_shentsize * shdr_symtab.sh_link, SEEK_SET);
fread(&shdr_strtab, sizeof(Elf64_Shdr), 1, f);
char * strtab = malloc(shdr_strtab.sh_size);
fseek(f, shdr_strtab.sh_offset, SEEK_SET);
fread(strtab, shdr_strtab.sh_size, 1, f);
/* Load relocations from file */
Elf64_Rela * relocations = malloc(sectionHeader.sh_size);
fseek(f, sectionHeader.sh_offset, SEEK_SET);
fread((void*)relocations, sectionHeader.sh_size, 1, f);
for (unsigned int i = 0; i < sectionHeader.sh_size / sizeof(Elf64_Rela); ++i) {
Elf64_Shdr shdr;
Elf64_Sym * this = &symtab[ELF64_R_SYM(relocations[i].r_info)];
char * symName;
/* Get symbol name for this relocation */
if ((this->st_info & 0xF) == STT_SECTION) {
fseek(f, header.e_shoff + header.e_shentsize * this->st_shndx, SEEK_SET);
fread(&shdr, sizeof(Elf64_Shdr), 1, f);
symName = stringTable + shdr.sh_name;
} else {
symName = strtab + this->st_name;
}
/* Get the value currently in the section data */
Elf64_Xword value = 0;
int valueSize = sizeOfRelocationValue(ELF64_R_TYPE(relocations[i].r_info));
fseek(f, shdr_this.sh_offset + relocations[i].r_offset, SEEK_SET);
switch (valueSize) {
case 8:
{
uint64_t val;
fread(&val, valueSize, 1, f);
value = val;
break;
}
case 4:
{
uint32_t val;
fread(&val, valueSize, 1, f);
value = val;
break;
}
case 2:
{
uint16_t val;
fread(&val, valueSize, 1, f);
value = val;
break;
}
case 1:
{
uint8_t val;
fread(&val, valueSize, 1, f);
value = val;
break;
}
default:
break;
}
printf("%012lx %012lx %-15.15s %016lx %s + %lx\n",
relocations[i].r_offset, relocations[i].r_info,
relocationInfoToStr(ELF64_R_TYPE(relocations[i].r_info)),
value,
symName,
relocations[i].r_addend);
}
free(relocations);
free(strtab);
free(symtab);
}
break;
case SHT_SYMTAB:
{
printf("\nSymbol table '%s' contains %ld entries.\n",
stringTable + sectionHeader.sh_name,
sectionHeader.sh_size / sizeof(Elf64_Sym));
printf(" Num: Value Size Type Bind Vis Ndx Name\n");
Elf64_Sym * symtab = malloc(sectionHeader.sh_size);
fseek(f, sectionHeader.sh_offset, SEEK_SET);
fread(symtab, sectionHeader.sh_size, 1, f);
Elf64_Shdr shdr_strtab;
fseek(f, header.e_shoff + header.e_shentsize * sectionHeader.sh_link, SEEK_SET);
fread(&shdr_strtab, sizeof(Elf64_Shdr), 1, f);
char * strtab = malloc(shdr_strtab.sh_size);
fseek(f, shdr_strtab.sh_offset, SEEK_SET);
fread(strtab, shdr_strtab.sh_size, 1, f);
for (unsigned int i = 0; i < sectionHeader.sh_size / sizeof(Elf64_Sym); ++i) {
printf("%6u: %016lx %6lu %-7.7s %-6.6s %-4d %6d %s\n",
i, symtab[i].st_value, symtab[i].st_size,
symbolTypeToStr(symtab[i].st_info & 0xF),
symbolBindToStr(symtab[i].st_info >> 4),
symtab[i].st_other,
symtab[i].st_shndx,
strtab + symtab[i].st_name);
}
free(strtab);
free(symtab);
}
break;
default:
break;
}
}
return 0;
} }