#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <unistd.h>
#include <elf.h>

void print_banner(void);
void die(int line,char *err,int code);
int is_elf(Elf32_Ehdr *elf);
char* check_type(Elf32_Ehdr *elf);

int main(int argc,char *argv[])
{
	int fd;
	unsigned int size;
	unsigned char * buf;
        struct stat stats;
        
        /* Elf32 Structure */
        Elf32_Ehdr *elf_header;
        
	if (!argv[1])
		die(__LINE__,"bad usage",-1);
	
	print_banner();
	
	printf( "@ File name           \t: %s .\n", argv[1] );
	
	if ((fd = open(argv[1],0x00)) < 0 ) /* Apro il file in modalità solo lettura O_RDONLY (fcntl.h) */
		die(__LINE__,"error opening file",-1);

	printf( "@ File descriptor     \t: %d .\n", fd );
	
        if( stat( argv[1], &stats ) < 0 ) /* Trovo la grandezza del file tramite stat */
		die(__LINE__,"error getting file size",-1);

        size = stats.st_size;
        
 	printf( "@ File size           \t: %d bytes .\n", size );
        
        buf = (char*)malloc(sizeof(char)*size+1); /* Alloco tot memoria quanto è grande il file */
        
	if ( read(fd,buf,size) != size) /* Leggo tanti bytes dal file quanto è grande */
		die(__LINE__,"error reading bytes",-1);

	close(fd);
	
        elf_header = (Elf32_Ehdr *)buf; /* Copio il buffer nella struttura Elf32_Ehdr */

	if (is_elf(elf_header) == -1)
		die(__LINE__,"bad elf file",-1);
        
        printf("@ Entry point      \t: 0x%X .\n", elf_header->e_entry ); /* Ed ecco l'entry point del nostro file */
	
	printf("@ Type                 \t: %s .\n",check_type(elf_header));
	
	free(buf); /* Libero la memoria del buffer */
	
	return 0;
}

void die(int line,char *err,int code)
{
	printf("[-]Line %d: %s.\n",line,err);
	exit(code);
}

void print_banner(void)
{
	printf("\t~~~ .text Finder 0.0.1 ~~~\nnex { www.0x80cd.netsons.org }\nReleased Under GNU Public License 3.0\n\n");
}

int is_elf(Elf32_Ehdr *elf)
{
	if ((elf->e_ident[0] != 0x7f) ||
	    (elf->e_ident[1] != 'E' ) ||
	    (elf->e_ident[2] != 'L' ) ||
	    (elf->e_ident[3] != 'F' ) ||
	    (elf->e_ident[4] !=  1  ) ||
	    (elf->e_ident[5] !=  1  ))
	return -1;
	return 0;
}

char* check_type(Elf32_Ehdr *elf)
{
	char *types[] = { "None" , "Relocatable" , "Executable" , "Shared Object" , "Core" , "Defined Types" };
	if (is_elf(elf) == 0)
	{
		return (char*)types[elf->e_type];
	}
	return NULL;
}