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fail/src/core/util/elfinfo/elfinfo.cc
hoffmann 609ac58c8f ElfReader now supports section information. 
ElfReader can now get Section start address,
end address and size by its name.
Or the according section name to any address within
a section

See ElfReader.hpp for API.

git-svn-id: https://www4.informatik.uni-erlangen.de/i4svn/danceos/trunk/devel/fail@2070 8c4709b5-6ec9-48aa-a5cd-a96041d1645a
2013-02-07 00:51:25 +00:00

346 lines
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/* DISCLAIMER :This is a FREE SOFTWARE You can Use it at your own RISK
that is if you are screwed by using this software, then
accept the fact that you screwed yourself.
## THIS HAS BEEN DEVELOPED AND TESTED UNDER FEDORA-9 HOPEFULLY IT WILL
## WORK ON OTHER SYSTEMS
======================================================================
elfinfo.c - Copyright (C)2008 Ashok Shankar Das ashok.s.das@gmail.com
This code is free software; you can redistribute it and/or
modify it under the terms of the GNU Library General Public
License as published by the Free Software Foundation; either
version 2 of the License, or (at your option) any later version.
This code is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Library General Public License for more details.
You should have received a copy of the GNU Library General Public
License along with this library; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include <stdio.h>
#include <stdlib.h>
#include <fcntl.h>
#include <string.h>
#include <elf.h>
void read_ELF_file_header(FILE* fp,Elf32_Ehdr *filehdr)
{
//rewind(fp);
fread(filehdr,sizeof(Elf32_Ehdr),1,fp);
}
int is_ELF(Elf32_Ehdr *hdr)
{
if(strncmp(reinterpret_cast<const char*>(hdr->e_ident),"\177ELF",4)==0)
return 1;
else
return -1;
}
int read_ELF_section_header(int sect_num,Elf32_Shdr *sect_hdr,FILE *fp)
{
int numsect;
Elf32_Ehdr elfhdr;
off_t sect_hdr_off;
fseek(fp,(off_t)0,SEEK_SET);
read_ELF_file_header(fp,&elfhdr);
numsect=elfhdr.e_shnum;
if ((numsect<sect_num)||(sect_num<0))
return -1;
sect_hdr_off=elfhdr.e_shoff;
//rewind(fp);
sect_hdr_off+=elfhdr.e_shentsize*sect_num;
fseek(fp,(off_t)sect_hdr_off,SEEK_SET);
fread(sect_hdr,sizeof(Elf32_Shdr),1,fp);
return 1;
}
void process_sect_hdr(Elf32_Shdr *sect_hdr,char *sect_name_buff)
{
int idx;
idx=sect_hdr->sh_name;
printf(" %-20s (0x%x++0x%x) ",sect_name_buff+idx, sect_hdr->sh_addr, sect_hdr->sh_size);
if(sect_hdr->sh_entsize)
printf(" %c ",'*');
else
printf(" %c ",' ');
switch(sect_hdr->sh_type)
{
case 0: printf("NULL \t");
break;
case 1: printf("PROGBITS \t");
break;
case 2: printf("SYMTAB \t");
break;
case 3: printf("STRTAB \t");
break;
case 4: printf("RELOC ADN \t");
break;
case 5: printf("HASH \t");
break;
case 6: printf("SYMTAB \t");
break;
case 7: printf("NOTE \t");
break;
case 8: printf("NOBIT \t");
break;
case 9: printf("RELOC \t");
break;
case 10: printf("*reserved* \t");
break;
case 11: printf("DYNSYM \t");
break;
case 14: printf("INITARR \t");
break;
case 15: printf("FINIARR \t");
break;
case 16: printf("PREINIT \t");
break;
case 17: printf("SECTGRP \t");
break;
case 18: printf("EXT-SHNDX \t");
break;
case 19: printf("NUM-DEF-TYP \t");
break;
case 0x60000000: printf("OS SPECIFIC \t");
break;
case 0x6ffffff5: printf("GNU_ATTR \t");
break;
case 0x6ffffff6: printf("GNU_HASH \t");
break;
case 0x6ffffff7: printf("PRELNKLIBLST \t");
break;
case 0x6ffffff8: printf("CKSUM \t");
break;
case 0x6ffffffa: printf("SUN SPECIFIC \t");
break;
case 0x6ffffffb: printf("SUNCOMDAT \t");
break;
case 0x6ffffffc: printf("SUNSYMINFO \t");
break;
case 0x6ffffffd: printf("GNUVERDEF \t");
break;
case 0x6ffffffe: printf("GNUVERNEED \t");
break;
case 0x6fffffff: printf("GNUVERSYM \t");
break;
case 0x70000000: printf("LOPROC \t");
break;
case 0x7fffffff: printf("HIPROC \t");
break;
case 0x80000000: printf("APP beg \t");
break;
case 0x8fffffff: printf("APP end \t");
break;
}
printf("linked to %3d sect\n",sect_hdr->sh_link);
}
void display_sections(FILE *fp)
{
Elf32_Ehdr ehdr;
Elf32_Shdr sec_hdr;
int num_hdrs,i;
char *buff=NULL;
fseek(fp,(off_t)0,SEEK_SET);
read_ELF_file_header(fp, &ehdr);
if(is_ELF(&ehdr)==-1)
{
printf("Not an ELF file\n");
exit(0);
}
num_hdrs=ehdr.e_shnum;
if(read_ELF_section_header(ehdr.e_shstrndx,&sec_hdr,fp)==-1)
{
printf("Error: reading section string table sect_num= %d\n",ehdr.e_shstrndx);
exit(0);
}
//we read the shstrtab
// read content from the file
buff=(char*)malloc(sec_hdr.sh_size);
if (!buff)
{
printf("Malloc failed to allocate buffer for shstrtab\n");
exit(0);
}
//seek to the offset in the file,
fseek(fp,(off_t)sec_hdr.sh_offset,SEEK_SET);
fread(buff,sec_hdr.sh_size,1,fp);
printf("There are [%d] sections\n",num_hdrs);
for(i=0;i<num_hdrs;i++)
{
if(read_ELF_section_header(i,&sec_hdr,fp)==-1)
{
printf("Wrong Section to read\n");
}
else
{
printf("[section %3d] ",i);
process_sect_hdr(&sec_hdr,buff);
}
}
if(buff)
free(buff);
}
int process_symtab(int sect_num,FILE *fp)
{
Elf32_Shdr sect_hdr;
Elf32_Sym mysym;
char *name_buf=NULL;
int num_sym,link,i,idx;
off_t sym_data_offset;
int sym_data_size;
if(read_ELF_section_header(sect_num,&sect_hdr,fp)==-1)
{
return -1;
}
//we have to check to which strtab it is linked
link=sect_hdr.sh_link;
sym_data_offset=sect_hdr.sh_offset;
sym_data_size=sect_hdr.sh_size;
num_sym=sym_data_size/sizeof(Elf32_Sym);
//read the coresponding strtab
if(read_ELF_section_header(link,&sect_hdr,fp)==-1)
{
return -1;
}
//get the size of strtab in file and allocate a buffer
name_buf=(char*)malloc(sect_hdr.sh_size);
if(!name_buf)
return -1;
//get the offset of strtab in file and seek to it
fseek(fp,sect_hdr.sh_offset,SEEK_SET);
//read all data from the section to the buffer.
fread(name_buf,sect_hdr.sh_size,1,fp);
//so we have the namebuf now seek to symtab data
fseek(fp,sym_data_offset,SEEK_SET);
printf("[%d] symbols\n",num_sym);
for(i=0;i<num_sym;i++)
{
//memcpy((char *)&mysym,(char *)sym_buf,sizeof(Elf32_Sym));
fread(&mysym,sizeof(Elf32_Sym),1,fp);
//dump_sym(&mysym);
idx=mysym.st_name;
//printf("symbol %d index in strtab %d\n",i,idx);
printf("[%3d] %s ",i,name_buf+idx);
switch(ELF32_ST_BIND(mysym.st_info))
{
case 0: printf(" LOCAL ");
break;
case 1: printf(" GLOBAL ");
break;
case 2: printf(" WEAK ");
break;
case 3: printf(" NUM ");
break;
case 10: printf(" OS-specific-start ");
break;
case 12: printf(" OS-specific-end ");
break;
case 13: printf(" CPU-specific-start ");
break;
case 15: printf("CPU-specific-end ");
break;
}
switch(ELF32_ST_TYPE(mysym.st_info))
{
case 0: printf(" NOTYPE ");
break;
case 1: printf(" OBJECT ");
break;
case 2: printf(" FUNC ");
break;
case 3: printf(" SECTION ");
break;
case 4: printf(" FILE ");
break;
case 5: printf(" COMMON ");
break;
case 6: printf(" TLS ");
break;
case 7: printf(" NUM ");
break;
case 10: printf(" OS-specific-start ");
break;
break;
case 12: printf(" OS-specific-end ");
break;
case 13: printf(" CPU-specific-start ");
break;
break;
case 15: printf(" CPU-specific-end ");
break;
}
switch(mysym.st_shndx)
{
case SHN_UNDEF: printf(" UNDEF ");
break;
case SHN_LOPROC: printf(" CPU-specific-start ");
break;
case SHN_HIPROC: printf(" CPU-specific-end ");
break;
case SHN_LOOS: printf(" OS-specific-start ");
break;
case SHN_HIOS: printf(" OS-specific-end ");
break;
case SHN_ABS: printf(" ABSOLUTE ");
break;
case SHN_COMMON: printf(" COMMON ");
break;
case SHN_XINDEX: printf(" XINDEX ");
break;
}
printf("\n");
}
if(name_buf)
free(name_buf);
return 0;
}
void dump_symbols(FILE *fp)
{
Elf32_Ehdr ehdr;
Elf32_Shdr sec_hdr;
int num_hdrs,i;
fseek(fp,(off_t)0,SEEK_SET);
read_ELF_file_header(fp, &ehdr);
num_hdrs=ehdr.e_shnum;
for(i=0;i<num_hdrs;i++)
{
if(read_ELF_section_header(i,&sec_hdr,fp)==-1)
{
printf("Wrong Section to read\n");
}
else
{
if((sec_hdr.sh_type==SHT_SYMTAB)||(sec_hdr.sh_type==SHT_DYNSYM))
{
printf("\n[section %3d] contains ",i);
process_symtab(i,fp);
}
else
continue;
}
}
}
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