/*
* Copyright (c) 2002-2009 Nokia Corporation and/or its subsidiary(-ies).
* All rights reserved.
* This component and the accompanying materials are made available
* under the terms of the License "Eclipse Public License v1.0"
* which accompanies this distribution, and is available
* at the URL "http://www.eclipse.org/legal/epl-v10.html".
*
* Initial Contributors:
* Nokia Corporation - initial contribution.
*
* Contributors:
*
* Description:
*
*/
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <elfdefs.h>
#include <sys/stat.h>
#if defined(__MSVCDOTNET__) || defined(__TOOLS2__)
#include <iostream>
#include <iomanip>
using namespace std;
#else //(!__MSVCDOTNET__ && !__TOOLS2__)
#include <iostream.h>
#include <iomanip.h>
#endif //__MSVCDOTNET__
#define ADDR(rtype, p, o) (rtype *)(((char *)p) + o)
bool ignoreSomeSections;
void hexdump(unsigned char* data, int aSize, int offset)
// print hex dump of relevant sections
{
int i=0;
int p=0;
while (i<aSize)
{
int count=0;
if(p==0){printf("\t%06x ",offset);} // offset into section
while (i<aSize && count<4)
{
printf("%02X", *data); // print 4 lots of %08x for the data expresed as 32-bit word
data++;
i++;
count++;
offset++;
}
printf(" ");
p++;
if (p==4)
{
data=data-16;
for (int i=0;i<16;i++) //print 16 bytes of memory interpreted
{ //as ASCII characters with all non-printing
if (*data>32 && *data <127) //characters converted to dots
{
printf("%1c",*data);
}
else
{
printf(".");
}
data++;
}
p=0;
printf(" \n ");
}
}
printf(" \n\n ");
}
void print_directive(unsigned char* data, int size)
// print formatted text of directive section
{
printf ("\t");
for (int i=0; i<size; i++)
{
if ((char)data[i]>31 && (char)data[i]<127)
{
printf ("%c", (char)data[i]);
}
if ((char)data[i]=='\n')
{
printf ("\n\t");
}
}
printf ("\n");
}
void print_reloc(Elf32_Ehdr* eh, Elf32_Sym* symT, unsigned char* strtab)
// print relocation section
{
Elf32_Shdr* shdr = ADDR(Elf32_Shdr, eh, eh->e_shoff);
for (int j=0;j< eh->e_shnum;j++)
{
char* sname = ADDR(char, eh, shdr[eh->e_shstrndx].sh_offset);
if ( (shdr[j].sh_type==9) &&
( (!ignoreSomeSections) ||
(strncmp(".rel.debug_", &sname[shdr[j].sh_name], 11))
)
)
{
unsigned char* data = ADDR(unsigned char, eh, shdr[j].sh_offset);
int noOfReloc=shdr[j].sh_size / shdr[j].sh_entsize;
printf("\n\n\n\t\t\t%s\n", &sname[shdr[j].sh_name]);
Elf32_Rel* rl=(Elf32_Rel*)data; // pointer to relocation section
for (int i=0;i<noOfReloc;i++)
{
unsigned char* symbolName = strtab; // pointer to firest element of string // table which holds symbol names
Elf32_Sym* sym = symT; // pointer to symbol table
int symTIndx= ELF32_R_SYM(rl->r_info); // symbol Tableindex
sym=sym+symTIndx;
symbolName=symbolName+sym->st_name; // index into string table section
// with symbol names
printf("\t0x%08x \t", rl->r_offset); // prints offset into relocation section
printf("%d", symTIndx); // symbol table index
printf("\t%s\n",symbolName); // symbol name
rl++;
}
}
}
}
void print_GlSymbols(Elf32_Ehdr* eh, Elf32_Sym* symT, unsigned char* strtab)
// print global symbols from Symbol Table
{
Elf32_Shdr* shdr = ADDR(Elf32_Shdr, eh, eh->e_shoff);
char* sname = ADDR(char, eh, shdr[eh->e_shstrndx].sh_offset);
for (int i=0;i< eh->e_shnum;i++)
{
if (!strcmp(".symtab", &sname[shdr[i].sh_name]))
{
int noOfSym=shdr[i].sh_size / shdr[i].sh_entsize; // number of symbols
const char *symName =(const char *)strtab;
int count = 1;
printf("Global symbols:\n");
printf("=================\n\n");
for (int l=0;l< noOfSym ;l++)
{
symT=symT+1;
if( ELF32_ST_BIND(symT->st_info) == 1) // searching for global symbols
{
symName = symName + symT->st_name; // index into string table section
printf("%d ",count);
printf(symName);
printf("\n");
symName = symName - symT->st_name; // back to pointing to first byte of string table
count++;
}
}
}
}
}
void print_elf_header(Elf32_Ehdr* eh)
{
// print elf header
if (eh->e_version==1)
printf("\tHeader version: EV_CURRENT (Current version)\n");
else
printf("\tInvalid version: EV_NONE (Invalid version)\n");
if (eh->e_type==0)
printf("\tFile Type: ET_NONE (No file type) (0)\n");
else if (eh->e_type==1)
printf("\tFile Type: ET_REL (Relocatable object) (1)\n");
else if (eh->e_type==2)
printf("\tFile Type: ET_EXEC (Executable file) (2)\n");
else if (eh->e_type==3)
printf("\tFile Type: ET_DYN (Shared object file) (3)\n");
else if (eh->e_type==4)
printf("\tFile Type: ET_CORE (Core File) (4)\n");
else if (eh->e_type==65280)
printf("\tFile Type: ET_LOPROC (Precessor Specific) (ff00)\n");
else
printf("\tFile Type: ET_HIPROC (Precessor Specific) (ffff)\n");
if (eh->e_machine==40)
printf("\tMachine: EM_ARM (ARM)\n");
else
printf("\tERROR:\tUnexpected machine\n");
printf("\tEntry offset (in SHF_ENTRYSECT section):0x%08x \n",eh->e_entry);
printf("\tProgram header entries : %d\n",eh->e_phnum);
printf("\tSection header entries : %d\n",eh->e_shnum);
printf("\tProgram header offset : %d",eh->e_phoff);
printf(" bytes (0x%08X",eh->e_phoff);
printf(")\n");
printf("\tSection header offset : %d",eh->e_shoff);
printf(" bytes (0x%08X",eh->e_shoff);
printf(")\n");
printf("\tProgram header entry size : %d",eh->e_phentsize);
printf(" bytes (0x%02X",eh->e_phentsize);
printf(")\n");
printf("\tSection header entry size : %d",eh->e_shentsize);
printf(" bytes (0x%02X",eh->e_shentsize);
printf(")\n");
printf("\tSection header string table index: %d \n", eh->e_shstrndx);
printf("\tHeader size: %d", eh->e_ehsize);
printf(" bytes (0x%02X",eh->e_ehsize);
printf(")\n");
}
void print_sect_header(char* sname, Elf32_Shdr* shdr, int count)
// print section header names
{
static const char* KtypeName[]={"0","SHT_PROGBITS (1)","SHT_SYMTAB (2)","SHT_STRTAB (3)",
"SHT_RELA (4)","5", "SHT_DINAMIC (6)","7","8","SHT_REL (9)",
"10","SHT_DINSYM (11)"};
printf("\n\n\tName\t\t:%1s\n ",&sname[shdr[count].sh_name]);
printf("\tType\t\t: %s\n", KtypeName[shdr[count].sh_type]);
printf("\tAddr\t\t: 0x%08X\n",shdr[count].sh_addr);
printf("\tSize\t\t: %1d", shdr[count].sh_size);
printf(" bytes (0x%X",shdr[count].sh_size);
printf(")\n");
printf("\tEntry Size\t: %1d\n",shdr[count].sh_entsize);
printf("\tAligment\t: %1d\n\n\n",shdr[count].sh_addralign);
}
unsigned char* findSymbolStringT(Elf32_Ehdr* eh)
//calculate and return pointer to the first byte of string table(the one with symbol names)
{
Elf32_Shdr* shdr = ADDR(Elf32_Shdr, eh, eh->e_shoff);
char* sname = ADDR(char, eh, shdr[eh->e_shstrndx].sh_offset);
for (int i=0;i < eh->e_shnum; i++)
{
if (!strcmp(".strtab", &sname[shdr[i].sh_name]))
{
unsigned char* data = ADDR(unsigned char, eh, shdr[i].sh_offset);
return data; //pointer to the first byte of string table section
}
}
return NULL; //if not found
}
Elf32_Sym* findSymbolT(Elf32_Ehdr* eh)
//calculate and return pointer to the first element of symbol table
{
Elf32_Shdr* shdr = ADDR(Elf32_Shdr, eh, eh->e_shoff);
for (int i=0;i < eh->e_shnum;i++)
{
if (shdr[i].sh_type==2)
{
unsigned char* data = ADDR(unsigned char, eh, shdr[i].sh_offset);
Elf32_Sym* sym=(Elf32_Sym*)data;
return sym; //pointer to the first element of symbol table.
}
}
return NULL; // if not found
}
void print_Summary(Elf32_Ehdr* eh)
{
//print section names
Elf32_Shdr* shdr = ADDR(Elf32_Shdr, eh, eh->e_shoff);
char* sname = ADDR(char, eh, shdr[eh->e_shstrndx].sh_offset);
printf("\nSummary: \n");
printf("==========\n");
for (int i=0;i< eh->e_shnum;i++)
{
printf(&sname[shdr[i].sh_name]);
printf("\n");
}
}
bool printAll;
int do_elf_file(char* buffer, char* name)
{
Elf32_Ehdr* eh=(Elf32_Ehdr *)buffer; //elf header
if (eh->e_ident[EI_MAG0] !=0x7f || eh->e_ident[EI_MAG1] != 0x45 || eh->e_ident[EI_MAG2] !=0x4c || eh->e_ident[EI_MAG3] != 0x46)
{
// EI_MAG0 to EI_MAG3 - A files' first 4 bytes hold a 'magic number', identifying the file as an ELF object file.
cout << "Error: " << name << " is not a valid ELF file";
return 1;
}
if (eh->e_ident[EI_DATA] == 2)
{
// ELF Header size should be 52 bytes or converted into Big-Endian system 13312
if (eh->e_ehsize != 13312)
{
printf("\tERROR:\tELF Header contains invalid file type\n");
exit(1);
}
// e_ident[EI_DATA] specifies the data encoding of the processor-specific data in the object file.
printf("\tERROR:\tData encoding ELFDATA2MSB (Big-Endian) not supported\n");
exit(1);
}
if (eh->e_ehsize != 52)
{
// ELF Header size should be 52 bytes
printf("\tERROR:\tELF Header contains invalid file type\n");
exit(1);
}
int shoff = eh->e_shoff; // offset of section header table
Elf32_Shdr* shdr = ADDR(Elf32_Shdr, eh, shoff); // calculating pointer to Secton Header Table
// Elf32_Shdr * shdr = (Elf32_Shdr *)(buffer+shoff);
int shnum = eh->e_shnum; // number of section headers
int shstrndx = eh->e_shstrndx;
int snameoffset = shdr[shstrndx].sh_offset; // offset in file of sections' names
char* sname = ADDR(char, eh, snameoffset); // pointer to String Table which holds section names
// char * sname = (char *)(buffer+snameoffset);
print_elf_header(eh); // print Elf Header
Elf32_Sym* symT= findSymbolT(eh); // pointer to Symbol table
if (symT==NULL)
{
printf("\nSymbol table not found\n");
}
unsigned char* strtab=findSymbolStringT(eh); // pointer to String table which holds symbol names
if (strtab==NULL)
{
printf("\nString (the one which holds symbol names) table not found\n");
}
print_reloc(eh,symT, strtab); // print relocation info showing symbol names and
// and the name of section in which the relocaton occurs.
for(int i = 0; i < shnum; i++)
{
unsigned char* data = ADDR(unsigned char, eh, shdr[i].sh_offset); //pointer to the first byte in the section
//unsigned char * data = (unsigned char * )(buffer+shdr[i].sh_offset);
int size = shdr[i].sh_size; // section size in bytes
//print directive section
if (!strcmp(".directive", &sname[shdr[i].sh_name]))
{
print_sect_header(sname, shdr, i);
print_directive(data,size);
}
if (!strcmp(".symtab", &sname[shdr[i].sh_name]))
{
print_sect_header(sname, shdr, i);
// print global symbols
print_GlSymbols(eh,symT, strtab);
}
//print relevant section header names
//print hex dump of relevant sections
if (shdr[i].sh_type==1 || shdr[i].sh_type==4 || shdr[i].sh_type==6 ||
shdr[i].sh_type==9 || shdr[i].sh_type==11)
{
if (strcmp(".comment", &sname[shdr[i].sh_name])&&
strcmp(".line", &sname[shdr[i].sh_name]) &&
strcmp(".hash", &sname[shdr[i].sh_name]) &&
strcmp(".note", &sname[shdr[i].sh_name]) &&
strcmp(".directive", &sname[shdr[i].sh_name]) &&
strncmp(".debug",&sname[shdr[i].sh_name] ,6))
{
if ( ! ( (ignoreSomeSections) &&
(strncmp(".rel.debug_", &sname[shdr[i].sh_name], 11)==0)
)
)
{
print_sect_header(sname, shdr, i);
hexdump(data,size,i);
}
}
}
if (printAll) // displays extra information
{
if(i!=0)
{
print_sect_header(sname, shdr, i);
hexdump(data,size,i);
}
}
}
print_Summary(eh); // print section names
return 0;
}
int read_ar_element_header(char* ptr)
{
int length = strtol(ptr+48,0,10);
if (strncmp(ptr+58, "\x60\x0A", 2) != 0)
{
return -1;
}
return length;
}
int main(int argc, char* argv[])
{
char* arg;
int numberOfOptions=2;
printAll=0;
ignoreSomeSections=0;
if (argc<2)
{
cout << "File not specified";
exit(1);
}
else if (argc>numberOfOptions+2)
{
cout << "Too many arguments";
exit(1);
}
else
{
for (int i=1;i<=argc-2;i++)
{
if ( strcmp("-i", argv[i]) ==0 )
{
ignoreSomeSections=1;
}
else if ( strcmp("-a", argv[i]) ==0 )
{
printAll=1;
}
}
arg=argv[argc-1];
}
struct stat results;
stat(arg, &results);
FILE *elffile;
if((elffile = fopen(arg, "rb" )) == NULL)
{
cout << "Error opening file " << arg;
exit (1);
}
char* buffer=new char [results.st_size];//allocating enough memory
fread( buffer, sizeof( char ), results.st_size, elffile);
fclose(elffile);
if (strncmp(buffer, "!<arch>\x0A", 8) != 0)
{
// plain ELF file
if (do_elf_file(buffer, arg) != 0)
{
return 1;
}
return 0;
}
// library file
char* nextfile = buffer;
int remainder = results.st_size;
#define ADVANCE(n) nextfile+=(n); remainder-=(n);
ADVANCE(8);
while (remainder > 0)
{
int element_length = read_ar_element_header(nextfile);
ADVANCE(60);
if (element_length < 0 || element_length > remainder)
{
cout << "Error: archive file corrupt";
return 1;
}
if (strncmp(nextfile, "\x7F\x45\x4C\x46",4) == 0)
{
if (do_elf_file(nextfile, "archive_element") != 0)
{
return 1;
}
}
element_length += element_length&1; // round up to a multiple of 2
ADVANCE(element_length);
}
return 0;
}