/* binary (ELF) to shellcode converter */
/* by Dalnet SLACKo  slacko@mail.ru    */
#include <stdio.h>
#include <fcntl.h>
#include <sys/stat.h>
#include <sys/mman.h>
#include <linux/elf.h>
	int main(int argc,char **argv) {
		Elf32_Ehdr _ehdr;
		Elf32_Shdr _shdr;
		struct stat _info;
		unsigned long _mapped;
		unsigned long _offset;
		int fd,i,_shnum;
		int _nextsize = 0;
		stat(argv[1],&_info);
		if(argc!=2) { 
		fprintf(stderr,"Usage %s <binary-file>\n",argv[0]);
		exit(1);
			}
		if((fd = open(argv[1],O_RDWR,0)) == -1) {
			perror("open()");
			exit(1);
			}
		(void *)_mapped = mmap(0,_info.st_size,PROT_READ|PROT_WRITE,MAP_SHARED,fd,0);
		if( *(long *)_mapped !=  (long)0x464c457f)  {
			fprintf(stderr,"File is not an ELF binary file\n");
			exit(1);
			}
		_ehdr = *(Elf32_Ehdr *)_mapped;
		_shnum = _ehdr.e_shnum;
		_shdr = *(Elf32_Shdr *)(_mapped + _ehdr.e_shoff);
		_offset = _ehdr.e_entry - 0x08048000;
		for(i=0;i<_shnum;i++) {
			if(_shdr.sh_offset == _offset) 
				break; 
			else {
			_nextsize += sizeof(Elf32_Shdr); 
			_shdr = *(Elf32_Shdr *)(_mapped + _ehdr.e_shoff + _nextsize);
			}
		  }
		printf("Shellcode size %d bytes\n",_shdr.sh_size);
		for(i=0;i<_shdr.sh_size;i++) {
		  if(!(i % 10) && i!=0) 
			printf("\"\n\"");
		  if(i == 0) 
			printf("\n\"");
		printf("\\x%x",*(unsigned char *)(_mapped + _offset + i));
			}
		printf("\"\n\n");
		munmap((void *)_mapped,_info.st_size);
		close(fd);
		}