/*
 * ~[ fm-dmpsc.c ]  
 *
 * Dump the opcodes from a file, starting from an offset provided.
 *
 * written by -( nemo @ felinemenace.org )-
 *
 *                    _,'|             _.-''``-...___..--';)
 *                    /_ \'.      __..-' ,      ,--...--'''
 *                   <\    .`--'''       `     /'
 *                   `-';'               ;   ; ;
 *              __...--''     ___...--_..'  .;.'
 *          fL (,__....----'''       (,..--''  
 *     -( http://www.felinemenace.org )-
 *
 */

#include <stdio.h>
#include <errno.h>

#define MAXSC  10000

void usage(char *file)
{
  printf("usage: %s <file> <offset1> [<offset2>]\n",file);
  exit(1);
}

int main(int ac, char **av)
{
  char shellcode[MAXSC] = "char shellcode[] = {\n\"";
  unsigned int curr,offset1,offset2 = 0xffffffff;
  FILE *fp;
  char *ptr = shellcode + strlen(shellcode) - 1;
  unsigned char hex;
  int cnt = 0;

  if(ac < 3 || ac > 4)
    usage(*av);
  sscanf(av[2],"%p",&offset1);
  if(av[3])
    sscanf(av[3],"%p",&offset2);
  if(offset2 <= offset1) 
    usage(*av);
  if(!(fp = fopen(av[1],"r+"))) {
    printf("Error opening file.\n");
    exit(1);
  }
  if(fseek(fp,offset1,SEEK_SET) == -1){
    printf("Error seeking to offset1.\n");
    exit(1);
  }
  do {
    if((offset1 + cnt) >= offset2) {
      break;
    }
    if(cnt && !(cnt % 16))  {
      strcat(ptr,"\"\n\"");
      ptr+=3;
    }
    strcat(ptr,"\\x");
    if(!(fread(&hex, 1,1,fp) ==1)) {
      if(errno) {
        printf("An error has occured reading from the file.\n");
        exit(1);
      }  
      break;
    }
    ptr+=3;
    sprintf(ptr,"%02x",hex);  
    cnt++;
  } while(ptr++ < (shellcode + MAXSC - 4)) ;
  strcat(ptr,"\"\n};\n");  
  printf("// shellcode generated by -( nemo@felinemenace.org )-\n");
  printf("%s\n",shellcode);

  return 0;
}