postlogin.c

文件传输协议linux 下vsftpd2.1.0.tar.gz

}

static int
port_active(struct vsf_session* p_sess)
{
  int ret = 0;
  if (p_sess->p_port_sockaddr != 0)
  {
    ret = 1;
    if (pasv_active(p_sess))
    {
      bug("port and pasv both active");
    }
  }
  return ret;
}

static int
pasv_active(struct vsf_session* p_sess)
{
  int ret = 0;
  if (p_sess->pasv_listen_fd != -1)
  {
    ret = 1;
    if (port_active(p_sess))
    {
      bug("pasv and port both active");
    }
  }
  return ret;
}

static void
port_cleanup(struct vsf_session* p_sess)
{
  vsf_sysutil_sockaddr_clear(&p_sess->p_port_sockaddr);
}

static void
pasv_cleanup(struct vsf_session* p_sess)
{
  if (p_sess->pasv_listen_fd != -1)
  {
    vsf_sysutil_close(p_sess->pasv_listen_fd);
    p_sess->pasv_listen_fd = -1;
  }
}

static void
handle_pasv(struct vsf_session* p_sess, int is_epsv)
{
  static struct mystr s_pasv_res_str;
  static struct vsf_sysutil_sockaddr* s_p_sockaddr;
  int bind_retries = 10;
  unsigned short the_port = 0;
  /* IPPORT_RESERVED */
  unsigned short min_port = 1024;
  unsigned short max_port = 65535;
  int is_ipv6 = vsf_sysutil_sockaddr_is_ipv6(p_sess->p_local_addr);
  if (is_epsv && !str_isempty(&p_sess->ftp_arg_str))
  {
    int argval;
    str_upper(&p_sess->ftp_arg_str);
    if (str_equal_text(&p_sess->ftp_arg_str, "ALL"))
    {
      p_sess->epsv_all = 1;
      vsf_cmdio_write(p_sess, FTP_EPSVALLOK, "EPSV ALL ok.");
      return;
    }
    argval = vsf_sysutil_atoi(str_getbuf(&p_sess->ftp_arg_str));
    if (argval < 1 || argval > 2 || (!is_ipv6 && argval == 2))
    {
      vsf_cmdio_write(p_sess, FTP_EPSVBAD, "Bad network protocol.");
      return;
    }
  }
  pasv_cleanup(p_sess);
  port_cleanup(p_sess);
  if (is_ipv6)
  {
    p_sess->pasv_listen_fd = vsf_sysutil_get_ipv6_sock();
  }
  else
  {
    p_sess->pasv_listen_fd = vsf_sysutil_get_ipv4_sock();
  }
  vsf_sysutil_activate_reuseaddr(p_sess->pasv_listen_fd);

  if (tunable_pasv_min_port > min_port && tunable_pasv_min_port <= max_port)
  {
    min_port = tunable_pasv_min_port;
  }
  if (tunable_pasv_max_port >= min_port && tunable_pasv_max_port < max_port)
  {
    max_port = tunable_pasv_max_port;
  }

  while (--bind_retries)
  {
    int retval;
    double scaled_port;
    the_port = vsf_sysutil_get_random_byte();
    the_port <<= 8;
    the_port |= vsf_sysutil_get_random_byte();
    scaled_port = (double) min_port;
    scaled_port += ((double) the_port / (double) 65536) *
                   ((double) max_port - min_port + 1);
    the_port = (unsigned short) scaled_port;
    vsf_sysutil_sockaddr_clone(&s_p_sockaddr, p_sess->p_local_addr);
    vsf_sysutil_sockaddr_set_port(s_p_sockaddr, the_port);
    retval = vsf_sysutil_bind(p_sess->pasv_listen_fd, s_p_sockaddr);
    if (!vsf_sysutil_retval_is_error(retval))
    {
      retval = vsf_sysutil_listen(p_sess->pasv_listen_fd, 1);
      if (!vsf_sysutil_retval_is_error(retval))
      {
        break;
      }
    }
    /* SELinux systems can give you an inopportune EACCES, it seems. */
    if (vsf_sysutil_get_error() == kVSFSysUtilErrADDRINUSE ||
        vsf_sysutil_get_error() == kVSFSysUtilErrACCES)
    {
      continue;
    }
    die("vsf_sysutil_bind / listen");
  }
  if (!bind_retries)
  {
    die("vsf_sysutil_bind");
  }
  if (is_epsv)
  {
    str_alloc_text(&s_pasv_res_str, "Entering Extended Passive Mode (|||");
    str_append_ulong(&s_pasv_res_str, (unsigned long) the_port);
    str_append_text(&s_pasv_res_str, "|).");
    vsf_cmdio_write_str(p_sess, FTP_EPSVOK, &s_pasv_res_str);
    return;
  }
  if (tunable_pasv_address != 0)
  {
    /* Report passive address as specified in configuration */
    if (vsf_sysutil_inet_aton(tunable_pasv_address, s_p_sockaddr) == 0)
    {
      die("invalid pasv_address");
    }
  }
  str_alloc_text(&s_pasv_res_str, "Entering Passive Mode (");
  if (!is_ipv6)
  {
    str_append_text(&s_pasv_res_str, vsf_sysutil_inet_ntop(s_p_sockaddr));
  }
  else
  {
    const void* p_v4addr = vsf_sysutil_sockaddr_ipv6_v4(s_p_sockaddr);
    if (p_v4addr)
    {
      str_append_text(&s_pasv_res_str, vsf_sysutil_inet_ntoa(p_v4addr));
    }
    else
    {
      str_append_text(&s_pasv_res_str, "0,0,0,0");
    }
  }
  str_replace_char(&s_pasv_res_str, '.', ',');
  str_append_text(&s_pasv_res_str, ",");
  str_append_ulong(&s_pasv_res_str, the_port >> 8);
  str_append_text(&s_pasv_res_str, ",");
  str_append_ulong(&s_pasv_res_str, the_port & 255);
  str_append_text(&s_pasv_res_str, ").");
  vsf_cmdio_write_str(p_sess, FTP_PASVOK, &s_pasv_res_str);
}

static void
handle_retr(struct vsf_session* p_sess)
{
  static struct mystr s_mark_str;
  static struct vsf_sysutil_statbuf* s_p_statbuf;
  struct vsf_transfer_ret trans_ret;
  int remote_fd;
  int opened_file;
  int is_ascii = 0;
  filesize_t offset = p_sess->restart_pos;
  p_sess->restart_pos = 0;
  if (!data_transfer_checks_ok(p_sess))
  {
    return;
  }
  if (p_sess->is_ascii && offset != 0)
  {
    vsf_cmdio_write(p_sess, FTP_FILEFAIL,
                    "No support for resume of ASCII transfer.");
    return;
  }
  resolve_tilde(&p_sess->ftp_arg_str, p_sess);
  vsf_log_start_entry(p_sess, kVSFLogEntryDownload);
  str_copy(&p_sess->log_str, &p_sess->ftp_arg_str);
  prepend_path_to_filename(&p_sess->log_str);
  if (!vsf_access_check_file(&p_sess->ftp_arg_str))
  {
    vsf_cmdio_write(p_sess, FTP_NOPERM, "Permission denied.");
    return;
  }
  opened_file = str_open(&p_sess->ftp_arg_str, kVSFSysStrOpenReadOnly);
  if (vsf_sysutil_retval_is_error(opened_file))
  {
    vsf_cmdio_write(p_sess, FTP_FILEFAIL, "Failed to open file.");
    return;
  }
  /* Lock file if required */
  if (tunable_lock_upload_files)
  {
    vsf_sysutil_lock_file_read(opened_file);
  }
  vsf_sysutil_fstat(opened_file, &s_p_statbuf);
  /* No games please */
  if (!vsf_sysutil_statbuf_is_regfile(s_p_statbuf))
  {
    /* Note - pretend open failed */
    vsf_cmdio_write(p_sess, FTP_FILEFAIL, "Failed to open file.");
    /* Irritating FireFox does RETR on directories, so avoid logging this
     * very common and noisy case.
     */
    if (vsf_sysutil_statbuf_is_dir(s_p_statbuf))
    {
      vsf_log_clear_entry(p_sess);
    }
    goto file_close_out;
  }
  /* Now deactive O_NONBLOCK, otherwise we have a problem on DMAPI filesystems
   * such as XFS DMAPI.
   */
  vsf_sysutil_deactivate_noblock(opened_file);
  /* Optionally, we'll be paranoid and only serve publicly readable stuff */
  if (p_sess->is_anonymous && tunable_anon_world_readable_only &&
      !vsf_sysutil_statbuf_is_readable_other(s_p_statbuf))
  {
    vsf_cmdio_write(p_sess, FTP_FILEFAIL, "Failed to open file.");
    goto file_close_out;
  }
  /* Set the download offset (from REST) if any */
  if (offset != 0)
  {
    vsf_sysutil_lseek_to(opened_file, offset);
  }
  str_alloc_text(&s_mark_str, "Opening ");
  if (tunable_ascii_download_enable && p_sess->is_ascii)
  {
    str_append_text(&s_mark_str, "ASCII");
    is_ascii = 1;
  }
  else
  {
    str_append_text(&s_mark_str, "BINARY");
  }
  str_append_text(&s_mark_str, " mode data connection for ");
  str_append_str(&s_mark_str, &p_sess->ftp_arg_str);
  str_append_text(&s_mark_str, " (");
  str_append_filesize_t(&s_mark_str,
                        vsf_sysutil_statbuf_get_size(s_p_statbuf));
  str_append_text(&s_mark_str, " bytes).");
  remote_fd = get_remote_transfer_fd(p_sess, str_getbuf(&s_mark_str));
  if (vsf_sysutil_retval_is_error(remote_fd))
  {
    goto port_pasv_cleanup_out;
  }
  trans_ret = vsf_ftpdataio_transfer_file(p_sess, remote_fd,
                                          opened_file, 0, is_ascii);
  if (vsf_ftpdataio_dispose_transfer_fd(p_sess) != 1 && trans_ret.retval == 0)
  {
    trans_ret.retval = -2;
  }
  p_sess->transfer_size = trans_ret.transferred;
  /* Log _after_ the blocking dispose call, so we get transfer times right */
  if (trans_ret.retval == 0)
  {
    vsf_log_do_log(p_sess, 1);
  }
  /* Emit status message _after_ blocking dispose call to avoid buggy FTP
   * clients truncating the transfer.
   */
  if (trans_ret.retval == -1)
  {
    vsf_cmdio_write(p_sess, FTP_BADSENDFILE, "Failure reading local file.");
  }
  else if (trans_ret.retval == -2)
  {
    vsf_cmdio_write(p_sess, FTP_BADSENDNET, "Failure writing network stream.");
  }
  else
  {
    vsf_cmdio_write(p_sess, FTP_TRANSFEROK, "File send OK.");
  }
  check_abor(p_sess);
port_pasv_cleanup_out:
  port_cleanup(p_sess);
  pasv_cleanup(p_sess);
file_close_out:
  vsf_sysutil_close(opened_file);
}

static void
handle_list(struct vsf_session* p_sess)
{
  handle_dir_common(p_sess, 1, 0);
}

static void
handle_dir_common(struct vsf_session* p_sess, int full_details, int stat_cmd)
{
  static struct mystr s_option_str;
  static struct mystr s_filter_str;
  static struct mystr s_dir_name_str;
  static struct vsf_sysutil_statbuf* s_p_dirstat;
  int dir_allow_read = 1;
  struct vsf_sysutil_dir* p_dir = 0;
  int retval = 0;
  int use_control = 0;
  str_empty(&s_option_str);
  str_empty(&s_filter_str);
  /* By default open the current directory */
  str_alloc_text(&s_dir_name_str, ".");
  if (!stat_cmd && !data_transfer_checks_ok(p_sess))
  {
    return;
  }
  /* Do we have an option? Going to be strict here - the option must come
   * first. e.g. "ls -a .." fine, "ls .. -a" not fine
   */
  if (!str_isempty(&p_sess->ftp_arg_str) &&
      str_get_char_at(&p_sess->ftp_arg_str, 0) == '-')
  {
    /* Chop off the '-' */
    str_mid_to_end(&p_sess->ftp_arg_str, &s_option_str, 1);
    /* A space will separate options from filter (if any) */
    str_split_char(&s_option_str, &s_filter_str, ' ');
  }
  else
  {
    /* The argument, if any, is just a filter */
    str_copy(&s_filter_str, &p_sess->ftp_arg_str);
  }
  if (!str_isempty(&s_filter_str))
  {
    resolve_tilde(&s_filter_str, p_sess);
    if (!vsf_access_check_file(&s_filter_str))
    {
      vsf_cmdio_write(p_sess, FTP_NOPERM, "Permission denied.");
      return;
    }
    /* First check - is it an outright directory, as in "ls /pub" */
    p_dir = str_opendir(&s_filter_str);
    if (p_dir != 0)
    {
      /* Listing a directory! */
      str_copy(&s_dir_name_str, &s_filter_str);
      str_free(&s_filter_str);
    }
    else
    {
      struct str_locate_result locate_result =
        str_locate_char(&s_filter_str, '/');
      if (locate_result.found)
      {
        /* Includes a path! Reverse scan for / in the arg, to get the
         * base directory and filter (if any)
         */
        str_copy(&s_dir_name_str, &s_filter_str);
        str_split_char_reverse(&s_dir_name_str, &s_filter_str, '/');
        /* If we have e.g. "ls /.message", we just ripped off the leading
         * slash because it is the only one!
         */
        if (str_isempty(&s_dir_name_str))
        {
          str_alloc_text(&s_dir_name_str, "/");
        }
      }
    }
  }
  if (p_dir == 0)
  {
    /* NOTE - failure check done below, it's not forgotten */
    p_dir = str_opendir(&s_dir_name_str);
  }
  /* Fine, do it */
  if (stat_cmd)
  {
    use_control = 1;
    str_append_char(&s_option_str, 'a');
    vsf_cmdio_write_hyphen(p_sess, FTP_STATFILE_OK, "Status follows:");
  }
  else
  {
    int remote_fd = get_remote_transfer_fd(
      p_sess, "Here comes the directory listing.");
    if (vsf_sysutil_retval_is_error(remote_fd))
    {
      goto dir_close_out;
    }
  }
  if (p_sess->is_anonymous && p_dir && tunable_anon_world_readable_only)
  {
    vsf_sysutil_dir_stat(p_dir, &s_p_dirstat);
    if (!vsf_sysutil_statbuf_is_readable_other(s_p_dirstat))
    {
      dir_allow_read = 0;
    }
  }
  if (p_dir != 0 && dir_allow_read)
  {
    retval = vsf_ftpdataio_transfer_dir(p_sess, use_control, p_dir,
                                        &s_dir_name_str, &s_option_str,
                                        &s_filter_str, full_details);
  }
  if (!stat_cmd)
  {
    if (vsf_ftpdataio_dispose_transfer_fd(p_sess) != 1 && retval == 0)
    {
      retval = -1;
    }
  }
  if (stat_cmd)
  {
    vsf_cmdio_write(p_sess, FTP_STATFILE_OK, "End of status");
  }
  else if (p_dir == 0 || !dir_allow_read)
  {
    vsf_cmdio_write(p_sess, FTP_TRANSFEROK,
                    "Transfer done (but failed to open directory).");
  }
  else if (retval == 0)
  {
    vsf_cmdio_write(p_sess, FTP_TRANSFEROK, "Directory send OK.");
  }
  else
  {
    vsf_cmdio_write(p_sess, FTP_BADSENDNET, "Failure writing network stream.");
  }
  check_abor(p_sess);
dir_close_out:
  if (p_dir)
  {
    vsf_sysutil_closedir(p_dir);
  }
  if (!stat_cmd)
  {
    port_cleanup(p_sess);
    pasv_cleanup(p_sess);
  }
}

static void
handle_type(struct vsf_session* p_sess)
{
  str_upper(&p_sess->ftp_arg_str);
  if (str_equal_text(&p_sess->ftp_arg_str, "I") ||
      str_equal_text(&p_sess->ftp_arg_str, "L8") ||
      str_equal_text(&p_sess->ftp_arg_str, "L 8"))
  {
    p_sess->is_ascii = 0;
    vsf_cmdio_write(p_sess, FTP_TYPEOK, "Switching to Binary mode.");
  }
  else if (str_equal_text(&p_sess->ftp_arg_str, "A") ||
           str_equal_text(&p_sess->ftp_arg_str, "A N"))
  {
    p_sess->is_ascii = 1;
    vsf_cmdio_write(p_sess, FTP_TYPEOK, "Switching to ASCII mode.");
  }
  else
  {
    vsf_cmdio_write(p_sess, FTP_BADCMD, "Unrecognised TYPE command.");
  }
}

static void
handle_port(struct vsf_session* p_sess)
{
  unsigned short the_port;
  unsigned char vals[6];
  const unsigned char* p_raw;
  pasv_cleanup(p_sess);
  port_cleanup(p_sess);
  p_raw = vsf_sysutil_parse_uchar_string_sep(&p_sess->ftp_arg_str, ',', vals,
                                             sizeof(vals));