ftp.c

 */

static
CURLcode ftp_use_port(struct connectdata *conn)
{
  struct SessionHandle *data=conn->data;
  int portsock=-1;
  ssize_t nread;
  int ftpcode; /* receive FTP response codes in this */
  CURLcode result;

#ifdef ENABLE_IPV6
  /******************************************************************
   *
   * Here's a piece of IPv6-specific code coming up
   *
   */

  struct addrinfo hints, *res, *ai;
  struct sockaddr_storage ss;
  socklen_t sslen;
  char hbuf[NI_MAXHOST];

  struct sockaddr *sa=(struct sockaddr *)&ss;
#ifdef NI_WITHSCOPEID
  const int niflags = NI_NUMERICHOST | NI_NUMERICSERV | NI_WITHSCOPEID;
#else
  const int niflags = NI_NUMERICHOST | NI_NUMERICSERV;
#endif
  unsigned char *ap;
  unsigned char *pp;
  char portmsgbuf[4096], tmp[4096];

  const char *mode[] = { "EPRT", "LPRT", "PORT", NULL };
  char **modep;

  /*
   * we should use Curl_if2ip?  given pickiness of recent ftpd,
   * I believe we should use the same address as the control connection.
   */
  sslen = sizeof(ss);
  if (getsockname(conn->firstsocket, (struct sockaddr *)&ss, &sslen) < 0)
    return CURLE_FTP_PORT_FAILED;
  
  if (getnameinfo((struct sockaddr *)&ss, sslen, hbuf, sizeof(hbuf), NULL, 0,
                  niflags))
    return CURLE_FTP_PORT_FAILED;

  memset(&hints, 0, sizeof(hints));
  hints.ai_family = sa->sa_family;
  /*hints.ai_family = ss.ss_family;
    this way can be used if sockaddr_storage is properly defined, as glibc 
    2.1.X doesn't do*/
  hints.ai_socktype = SOCK_STREAM;
  hints.ai_flags = AI_PASSIVE;

  if (getaddrinfo(hbuf, (char *)"0", &hints, &res))
    return CURLE_FTP_PORT_FAILED;
  
  portsock = -1;
  for (ai = res; ai; ai = ai->ai_next) {
    portsock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
    if (portsock < 0)
      continue;

    if (bind(portsock, ai->ai_addr, ai->ai_addrlen) < 0) {
      sclose(portsock);
      portsock = -1;
      continue;
    }
      
    if (listen(portsock, 1) < 0) {
      sclose(portsock);
      portsock = -1;
      continue;
    }
    
    break;
  }
  freeaddrinfo(res);
  if (portsock < 0) {
    failf(data, "%s", strerror(errno));
    return CURLE_FTP_PORT_FAILED;
  }

  sslen = sizeof(ss);
  if (getsockname(portsock, sa, &sslen) < 0) {
    failf(data, "%s", strerror(errno));
    return CURLE_FTP_PORT_FAILED;
  }

  for (modep = (char **)(data->set.ftp_use_eprt?&mode[0]:&mode[2]);
       modep && *modep; modep++) {
    int lprtaf, eprtaf;
    int alen=0, plen=0;
    
    switch (sa->sa_family) {
    case AF_INET:
      ap = (unsigned char *)&((struct sockaddr_in *)&ss)->sin_addr;
      alen = sizeof(((struct sockaddr_in *)&ss)->sin_addr);
      pp = (unsigned char *)&((struct sockaddr_in *)&ss)->sin_port;
      plen = sizeof(((struct sockaddr_in *)&ss)->sin_port);
      lprtaf = 4;
      eprtaf = 1;
      break;
    case AF_INET6:
      ap = (unsigned char *)&((struct sockaddr_in6 *)&ss)->sin6_addr;
      alen = sizeof(((struct sockaddr_in6 *)&ss)->sin6_addr);
      pp = (unsigned char *)&((struct sockaddr_in6 *)&ss)->sin6_port;
      plen = sizeof(((struct sockaddr_in6 *)&ss)->sin6_port);
      lprtaf = 6;
      eprtaf = 2;
      break;
    default:
      ap = pp = NULL;
      lprtaf = eprtaf = -1;
      break;
    }

    if (strcmp(*modep, "EPRT") == 0) {
      if (eprtaf < 0)
        continue;
      if (getnameinfo((struct sockaddr *)&ss, sslen,
                      portmsgbuf, sizeof(portmsgbuf), tmp, sizeof(tmp), niflags))
        continue;

      /* do not transmit IPv6 scope identifier to the wire */
      if (sa->sa_family == AF_INET6) {
        char *q = strchr(portmsgbuf, '%');
          if (q)
            *q = '\0';
      }

      result = Curl_ftpsendf(conn, "%s |%d|%s|%s|", *modep, eprtaf,
                             portmsgbuf, tmp);
      if(result)
        return result;
    } else if (strcmp(*modep, "LPRT") == 0 ||
               strcmp(*modep, "PORT") == 0) {
      int i;
      
      if (strcmp(*modep, "LPRT") == 0 && lprtaf < 0)
        continue;
      if (strcmp(*modep, "PORT") == 0 && sa->sa_family != AF_INET)
        continue;

      portmsgbuf[0] = '\0';
      if (strcmp(*modep, "LPRT") == 0) {
        snprintf(tmp, sizeof(tmp), "%d,%d", lprtaf, alen);
        if (strlcat(portmsgbuf, tmp, sizeof(portmsgbuf)) >=
            sizeof(portmsgbuf)) {
          continue;
        }
      }

      for (i = 0; i < alen; i++) {
        if (portmsgbuf[0])
          snprintf(tmp, sizeof(tmp), ",%u", ap[i]);
        else
          snprintf(tmp, sizeof(tmp), "%u", ap[i]);
        
        if (strlcat(portmsgbuf, tmp, sizeof(portmsgbuf)) >=
            sizeof(portmsgbuf)) {
          continue;
        }
      }
      
      if (strcmp(*modep, "LPRT") == 0) {
        snprintf(tmp, sizeof(tmp), ",%d", plen);
        
        if (strlcat(portmsgbuf, tmp, sizeof(portmsgbuf)) >= sizeof(portmsgbuf))
          continue;
      }

      for (i = 0; i < plen; i++) {
        snprintf(tmp, sizeof(tmp), ",%u", pp[i]);
        
        if (strlcat(portmsgbuf, tmp, sizeof(portmsgbuf)) >=
            sizeof(portmsgbuf)) {
          continue;
        }
      }
      
      result = Curl_ftpsendf(conn, "%s %s", *modep, portmsgbuf);
      if(result)
        return result;
    }
    
    result = Curl_GetFTPResponse(&nread, conn, &ftpcode);
    if(result)
      return result;
    
    if (ftpcode != 200) {
      continue;
    }
    else
      break;
  }
  
  if (!*modep) {
    sclose(portsock);
    failf(data, "PORT command attempts failed");
    return CURLE_FTP_PORT_FAILED;
  }
  /* we set the secondary socket variable to this for now, it
     is only so that the cleanup function will close it in case
     we fail before the true secondary stuff is made */
  conn->secondarysocket = portsock;
  
#else
  /******************************************************************
   *
   * Here's a piece of IPv4-specific code coming up
   *
   */
  struct sockaddr_in sa;
  struct Curl_dns_entry *h=NULL;
  unsigned short porttouse;
  char myhost[256] = "";
  bool sa_filled_in = FALSE;

  if(data->set.ftpport) {
    in_addr_t in;
    int rc;

    /* First check if the given name is an IP address */
    in=inet_addr(data->set.ftpport);

    if((in == CURL_INADDR_NONE) &&
       Curl_if2ip(data->set.ftpport, myhost, sizeof(myhost))) {
      rc = Curl_resolv(conn, myhost, 0, &h);
      if(rc == 1)
        rc = Curl_wait_for_resolv(conn, &h);
    }
    else {
      int len = strlen(data->set.ftpport);
      if(len>1) {
        rc = Curl_resolv(conn, data->set.ftpport, 0, &h);
        if(rc == 1)
          rc = Curl_wait_for_resolv(conn, &h);
      }
      if(h)
        strcpy(myhost, data->set.ftpport); /* buffer overflow risk */
    }
  }
  if(! *myhost) {
    /* pick a suitable default here */

    socklen_t sslen;
    
    sslen = sizeof(sa);
    if (getsockname(conn->firstsocket, (struct sockaddr *)&sa, &sslen) < 0) {
      failf(data, "getsockname() failed");
      return CURLE_FTP_PORT_FAILED;
    }

    sa_filled_in = TRUE; /* the sa struct is filled in */
  }

  if(h)
    /* when we return from here, we can forget about this */
    Curl_resolv_unlock(data, h);

  if ( h || sa_filled_in) {
    if( (portsock = socket(AF_INET, SOCK_STREAM, 0)) >= 0 ) {
      int size;
      
      /* we set the secondary socket variable to this for now, it
         is only so that the cleanup function will close it in case
         we fail before the true secondary stuff is made */
      conn->secondarysocket = portsock;

      if(!sa_filled_in) {
        memset((char *)&sa, 0, sizeof(sa));
        memcpy((char *)&sa.sin_addr,
               h->addr->h_addr,
               h->addr->h_length);
        sa.sin_family = AF_INET;
        sa.sin_addr.s_addr = INADDR_ANY;
      }

      sa.sin_port = 0;
      size = sizeof(sa);
      
      if(bind(portsock, (struct sockaddr *)&sa, size) >= 0) {
        /* we succeeded to bind */
        struct sockaddr_in add;
        socklen_t socksize = sizeof(add);

        if(getsockname(portsock, (struct sockaddr *) &add,
                       &socksize)<0) {
          failf(data, "getsockname() failed");
          return CURLE_FTP_PORT_FAILED;
        }
        porttouse = ntohs(add.sin_port);
        
        if ( listen(portsock, 1) < 0 ) {
          failf(data, "listen(2) failed on socket");
          return CURLE_FTP_PORT_FAILED;
        }
      }
      else {
        failf(data, "bind(2) failed on socket");
        return CURLE_FTP_PORT_FAILED;
      }
    }
    else {
      failf(data, "socket(2) failed (%s)");
      return CURLE_FTP_PORT_FAILED;
    }
  }
  else {
    failf(data, "could't find my own IP address (%s)", myhost);
    return CURLE_FTP_PORT_FAILED;
  }
  {
#ifdef HAVE_INET_NTOA_R
    char ntoa_buf[64];
#endif
    struct in_addr in;
    unsigned short ip[5];
    (void) memcpy(&in.s_addr,
                  h?*h->addr->h_addr_list:(char *)&sa.sin_addr.s_addr,
                  sizeof (in.s_addr));

#ifdef HAVE_INET_NTOA_R
    /* ignore the return code from inet_ntoa_r() as it is int or
       char * depending on system */
    inet_ntoa_r(in, ntoa_buf, sizeof(ntoa_buf));
    sscanf( ntoa_buf, "%hu.%hu.%hu.%hu",
            &ip[0], &ip[1], &ip[2], &ip[3]);
#else
    sscanf( inet_ntoa(in), "%hu.%hu.%hu.%hu",
            &ip[0], &ip[1], &ip[2], &ip[3]);
#endif
    infof(data, "Telling server to connect to %d.%d.%d.%d:%d\n",
          ip[0], ip[1], ip[2], ip[3], porttouse);
  
    result=Curl_ftpsendf(conn, "PORT %d,%d,%d,%d,%d,%d",
                         ip[0], ip[1], ip[2], ip[3],
                         porttouse >> 8,
                         porttouse & 255);
    if(result)
      return result;
  }

  result = Curl_GetFTPResponse(&nread, conn, &ftpcode);
  if(result)
    return result;

  if(ftpcode != 200) {
    failf(data, "Server does not grok PORT, try without it!");
    return CURLE_FTP_PORT_FAILED;
  }
#endif /* end of ipv4-specific code */

  return CURLE_OK;
}

/***********************************************************************
 *
 * ftp_use_pasv()
 *
 * Send the PASV command. PASV is the ftp client's way of asking the server to
 * open a second port that we can connect to (for the data transfer). This is
 * the opposite of PORT.
 */

static
CURLcode ftp_use_pasv(struct connectdata *conn,
                      bool *connected)
{
  struct SessionHandle *data = conn->data;
  ssize_t nread;
  char *buf = data->state.buffer; /* this is our buffer */
  int ftpcode; /* receive FTP response codes in this */
  CURLcode result;
  struct Curl_dns_entry *addr=NULL;
  Curl_ipconnect *conninfo;
  int rc;

  /*
    Here's the excecutive summary on what to do:

    PASV is RFC959, expect:
    227 Entering Passive Mode (a1,a2,a3,a4,p1,p2)

    LPSV is RFC1639, expect:
    228 Entering Long Passive Mode (4,4,a1,a2,a3,a4,2,p1,p2)

    EPSV is RFC2428, expect:
    229 Entering Extended Passive Mode (|||port|)

  */

  const char *mode[] = { "EPSV", "PASV", NULL };
  int results[] = { 229, 227, 0 };
  int modeoff;
  unsigned short connectport; /* the local port connect() should use! */
  unsigned short newport=0; /* remote port, not necessary the local one */
  
  /* newhost must be able to hold a full IP-style address in ASCII, which
     in the IPv6 case means 5*8-1 = 39 letters */
  char newhost[48];
  char *newhostp=NULL;
  
  for (modeoff = (data->set.ftp_use_epsv?0:1);
       mode[modeoff]; modeoff++) {
    result = Curl_ftpsendf(conn, "%s", mode[modeoff]);
    if(result)
      return result;
    result = Curl_GetFTPResponse(&nread, conn, &ftpcode);
    if(result)
      return result;
    if (ftpcode == results[modeoff])
      break;
  }

  if (!mode[modeoff]) {
    failf(data, "Odd return code after PASV");
    return CURLE_FTP_WEIRD_PASV_REPLY;
  }
  else if (227 == results[modeoff]) {
    int ip[4];
    int port[2];
    char *str=buf;

    /*
     * New 227-parser June 3rd 1999.
     * It now scans for a sequence of six comma-separated numbers and
     * will take them as IP+port indicators.
     *
     * Found reply-strings include:
     * "227 Entering Passive Mode (127,0,0,1,4,51)"
     * "227 Data transfer will passively listen to 127,0,0,1,4,51"
     * "227 Entering passive mode. 127,0,0,1,4,51"
     */
      
    while(*str) {
      if (6 == sscanf(str, "%d,%d,%d,%d,%d,%d",
                      &ip[0], &ip[1], &ip[2], &ip[3],
                      &port[0], &port[1]))
        break;
      str++;
    }

    if(!*str) {
      failf(data, "Couldn't interpret this 227-reply: %s", buf);
      return CURLE_FTP_WEIRD_227_FORMAT;
    }

    sprintf(newhost, "%d.%d.%d.%d", ip[0], ip[1], ip[2], ip[3]);
    newhostp = newhost;
    newport = (port[0]<<8) + port[1];
  }
  else if (229 == results[modeoff]) {
    char *ptr = strchr(buf, '(');
    if(ptr) {
      unsigned int num;
      char separator[4];
      ptr++;
      if(5  == sscanf(ptr, "%c%c%c%u%c",
                      &separator[0],
                      &separator[1],
                      &separator[2],
                      &num,
                      &separator[3])) {
        char sep1 = separator[0];
        int i;

        /* The four separators should be identical, or else this is an oddly
           formatted reply and we bail out immediately. */
        for(i=1; i<4; i++) {
          if(separator[i] != sep1) {
            ptr=NULL; /* set to NULL to signal error */
            break;
          }
        }
        if(ptr) {
          newport = num;

          /* we should use the same host we already are connected to */
          newhostp = conn->name;
        }
      }                      
      else
        ptr=NULL;
    }
    if(!ptr) {
      failf(data, "Weirdly formatted EPSV reply");
      return CURLE_FTP_WEIRD_PASV_REPLY;
    }
  }
  else
    return CURLE_FTP_CANT_RECONNECT;

  if(data->change.proxy && *data->change.proxy) {
    /*
     * This is a tunnel through a http proxy and we need to connect to the
     * proxy again here.
     *
     * We don't want to rely on a former host lookup that might've expired
     * now, instead we remake the lookup here and now!
     */
    rc = Curl_resolv(conn, conn->proxyhost, conn->port, &addr);
    if(rc == 1)
      rc = Curl_wait_for_resolv(conn, &addr);

    connectport =
      (unsigned short)conn->port; /* we connect to the proxy's port */    

  }
  else {
    /* normal, direct, ftp connection */
    rc = Curl_resolv(conn, newhostp, newport, &addr);
    if(rc == 1)
      rc = Curl_wait_for_resolv(conn, &addr);

    if(!addr) {
      failf(data, "Can't resolve new host %s:%d", newhostp, newport);
      return CURLE_FTP_CANT_GET_HOST;
    }
    connectport = newport; /* we connect to the remote port */
  }
    
  result = Curl_connecthost(conn,
                            addr,
                            connectport,
                            &conn->secondarysocket,
                            &conninfo,
                            connected);

  Curl_resolv_unlock(data, addr); /* we're done using this address */

  if(result)
    return result;

  /*
   * When this is used from the multi interface, this might've returned with
   * the 'connected' set to FALSE and thus we are now awaiting a non-blocking
   * connect to connect and we should not be "hanging" here waiting.
   */
  
  if(data->set.verbose)
    /* this just dumps information about this second connection */
    ftp_pasv_verbose(conn, conninfo, newhostp, connectport);
  
  if (data->set.tunnel_thru_httpproxy) {
    /* We want "seamless" FTP operations through HTTP proxy tunnel */
    result = Curl_ConnectHTTPProxyTunnel(conn, conn->secondarysocket,
                                         newhostp, newport);
    if(CURLE_OK != result)
      return result;
  }

  return CURLE_OK;
}

/*
 * Curl_ftp_nextconnect()
 *
 * This function shall be called when the second FTP connection has been
 * established and is confirmed connected.
 */

CURLcode Curl_ftp_nextconnect(struct connectdata *conn)
{
  struct SessionHandle *data=conn->data;
  char *buf = data->state.buffer; /* this is our buffer */
  CURLcode result;
  ssize_t nread;
  int ftpcode; /* for ftp status */

  /* the ftp struct is already inited in Curl_ftp_connect() */
  struct FTP *ftp = conn->proto.ftp;
  long *bytecountp = ftp->bytecountp;

  if(data->set.upload) {

    /* Set type to binary (unless specified ASCII) */
    result = ftp_transfertype(conn, data->set.ftp_ascii);
    if(result)
      return result;

    /* Send any PREQUOTE strings after transfer type is set? (Wesley Laxton)*/
    if(data->set.prequote) {
      if ((result = ftp_sendquote(conn, data->set.prequote)) != CURLE_OK)
        return result;
    }

    if(conn->resume_from) {
      /* we're about to continue the uploading of a file */
      /* 1. get already existing file's size. We use the SIZE
         command for this which may not exist in the server!
         The SIZE command is not in RFC959. */

      /* 2. This used to set REST. But since we can do append, we
         don't another ftp command. We just skip the source file
         offset and then we APPEND the rest on the file instead */

      /* 3. pass file-size number of bytes in the source file */
      /* 4. lower the infilesize counter */
      /* => transfer as usual */

      if(conn->resume_from < 0 ) {
        /* we could've got a specified offset from the command line,
           but now we know we didn't */
        ssize_t gottensize;

        if(CURLE_OK != ftp_getsize(conn, ftp->file, &gottensize)) {
          failf(data, "Couldn't get remote file size");
          return CURLE_FTP_COULDNT_GET_SIZE;
        }
        conn->resume_from = gottensize;
      }

      if(conn->resume_from) {
        /* do we still game? */
        int passed=0;
        /* enable append instead */
        data->set.ftp_append = 1;

        /* Now, let's read off the proper amount of bytes from the
           input. If we knew it was a proper file we could've just
           fseek()ed but we only have a stream here */
        do {
          int readthisamountnow = (conn->resume_from - passed);
          int actuallyread;

          if(readthisamountnow > BUFSIZE)
            readthisamountnow = BUFSIZE;

          actuallyread =
            conn->fread(data->state.buffer, 1, readthisamountnow,
                        conn->fread_in);

          passed += actuallyread;
          if(actuallyread != readthisamountnow) {
            failf(data, "Could only read %d bytes from the input", passed);
            return CURLE_FTP_COULDNT_USE_REST;
          }
        }
        while(passed != conn->resume_from);

        /* now, decrease the size of the read */
        if(data->set.infilesize>0) {
          data->set.infilesize -= conn->resume_from;

          if(data->set.infilesize <= 0) {
            infof(data, "File already completely uploaded\n");

            /* no data to transfer */
            result=Curl_Transfer(conn, -1, -1, FALSE, NULL, -1, NULL);
            
            /* Set no_transfer so that we won't get any error in
             * Curl_ftp_done() because we didn't transfer anything! */
            ftp->no_transfer = TRUE; 

            return CURLE_OK;
          }
        }
        /* we've passed, proceed as normal */
      }
    }

    /* Send everything on data->state.in to the socket */
    if(data->set.ftp_append) {
      /* we append onto the file instead of rewriting it */
      FTPSENDF(conn, "APPE %s", ftp->file);
    }
    else {
      FTPSENDF(conn, "STOR %s", ftp->file);
    }

    result = Curl_GetFTPResponse(&nread, conn, &ftpcode);
    if(result)
      return result;

    if(ftpcode>=400) {
      failf(data, "Failed FTP upload:%s", buf+3);
      /* oops, we never close the sockets! */
      return CURLE_FTP_COULDNT_STOR_FILE;
    }

    if(data->set.ftp_use_port) {
      /* PORT means we are now awaiting the server to connect to us. */
      result = AllowServerConnect(data, conn, conn->secondarysocket);
      if( result )
        return result;
    }

    *bytecountp=0;

    /* When we know we're uploading a specified file, we can get the file
       size prior to the actual upload. */

    Curl_pgrsSetUploadSize(data, data->set.infilesize);

    result = Curl_Transfer(conn, -1, -1, FALSE, NULL, /* no download */
                      conn->secondarysocket, bytecountp);
    if(result)
      return result;
      
  }
  else if(!data->set.no_body) {
    /* Retrieve file or directory */
    bool dirlist=FALSE;
    long downloadsize=-1;

    if(conn->bits.use_range && conn->range) {
      long from, to;
      int totalsize=-1;
      char *ptr;
      char *ptr2;

      from=strtol(conn->range, &ptr, 0);
      while(ptr && *ptr && (isspace((int)*ptr) || (*ptr=='-')))
        ptr++;
      to=strtol(ptr, &ptr2, 0);
      if(ptr == ptr2) {
        /* we didn't get any digit */
        to=-1;
      }
      if((-1 == to) && (from>=0)) {
        /* X - */
        conn->resume_from = from;
        infof(data, "FTP RANGE %d to end of file\n", from);
      }
      else if(from < 0) {
        /* -Y */
        totalsize = -from;
        conn->maxdownload = -from;
        conn->resume_from = from;
        infof(data, "FTP RANGE the last %d bytes\n", totalsize);
      }
      else {
        /* X-Y */
        totalsize = to-from;
        conn->maxdownload = totalsize+1; /* include the last mentioned byte */
        conn->resume_from = from;
        infof(data, "FTP RANGE from %d getting %d bytes\n", from,
              conn->maxdownload);
      }
      infof(data, "range-download from %d to %d, totally %d bytes\n",
            from, to, totalsize);
      ftp->dont_check = TRUE; /* dont check for successful transfer */
    }

    if((data->set.ftp_list_only) || !ftp->file) {
      /* The specified path ends with a slash, and therefore we think this
         is a directory that is requested, use LIST. But before that we
         need to set ASCII transfer mode. */
      dirlist = TRUE;

      /* Set type to ASCII */
      result = ftp_transfertype(conn, TRUE /* ASCII enforced */);
      if(result)
        return result;

      /* if this output is to be machine-parsed, the NLST command will be
         better used since the LIST command output is not specified or
         standard in any way */

      FTPSENDF(conn, "%s",
            data->set.customrequest?data->set.customrequest:
            (data->set.ftp_list_only?"NLST":"LIST"));
    }
    else {
      ssize_t foundsize;

      /* Set type to binary (unless specified ASCII) */
      result = ftp_transfertype(conn, data->set.ftp_ascii);
      if(result)
        return result;

      /* Send any PREQUOTE strings after transfer type is set? */
      if(data->set.prequote) {
        if ((result = ftp_sendquote(conn, data->set.prequote)) != CURLE_OK)
          return result;
      }

      /* Attempt to get the size, it'll be useful in some cases: for resumed
         downloads and when talking to servers that don't give away the size
         in the RETR response line. */
      result = ftp_getsize(conn, ftp->file, &foundsize);
      if(CURLE_OK == result) {
        if (data->set.max_filesize && foundsize > data->set.max_filesize) {
          failf(data, "Maximum file size exceeded");
          return CURLE_FILESIZE_EXCEEDED;
        }
        downloadsize = foundsize;
      }

      if(conn->resume_from) {

        /* Daniel: (August 4, 1999)
         *
         * We start with trying to use the SIZE command to figure out the size
         * of the file we're gonna get. If we can get the size, this is by far
         * the best way to know if we're trying to resume beyond the EOF.
         *
         * Daniel, November 28, 2001. We *always* get the size on downloads
         * now, so it is done before this even when not doing resumes. I saved
         * the comment above for nostalgical reasons! ;-)
         */
        if(CURLE_OK != result) {
          infof(data, "ftp server doesn't support SIZE\n");
          /* We couldn't get the size and therefore we can't know if there
             really is a part of the file left to get, although the server
             will just close the connection when we start the connection so it
             won't cause us any harm, just not make us exit as nicely. */
        }
        else {
          /* We got a file size report, so we check that there actually is a
             part of the file left to get, or else we go home.  */
          if(conn->resume_from< 0) {
            /* We're supposed to download the last abs(from) bytes */
            if(foundsize < -conn->resume_from) {
              failf(data, "Offset (%d) was beyond file size (%d)",
                    conn->resume_from, foundsize);
              return CURLE_FTP_BAD_DOWNLOAD_RESUME;
            }
            /* convert to size to download */
            downloadsize = -conn->resume_from;
            /* download from where? */
            conn->resume_from = foundsize - downloadsize;
          }
          else {
            if(foundsize < conn->resume_from) {
              failf(data, "Offset (%d) was beyond file size (%d)",
                    conn->resume_from, foundsize);
              return CURLE_FTP_BAD_DOWNLOAD_RESUME;
            }
            /* Now store the number of bytes we are expected to download */
            downloadsize = foundsize-conn->resume_from;
          }
        }

        if (downloadsize == 0) {
          /* no data to transfer */
          result=Curl_Transfer(conn, -1, -1, FALSE, NULL, -1, NULL);
          infof(data, "File already completely downloaded\n");

          /* Set no_transfer so that we won't get any error in Curl_ftp_done()
           * because we didn't transfer the any file */
          ftp->no_transfer = TRUE;
          return CURLE_OK;
        }
	
        /* Set resume file transfer offset */
        infof(data, "Instructs server to resume from offset %d\n",
              conn->resume_from);

        FTPSENDF(conn, "REST %d", conn->resume_from);

        result = Curl_GetFTPResponse(&nread, conn, &ftpcode);
        if(result)
          return result;

        if(ftpcode != 350) {
          failf(data, "Couldn't use REST: %s", buf+4);
          return CURLE_FTP_COULDNT_USE_REST;
        }
      }

      FTPSENDF(conn, "RETR %s", ftp->file);
    }

    result = Curl_GetFTPResponse(&nread, conn, &ftpcode);
    if(result)
      return result;

    if((ftpcode == 150) || (ftpcode == 125)) {

      /*
        A;
        150 Opening BINARY mode data connection for /etc/passwd (2241
        bytes).  (ok, the file is being transfered)
	
        B:
        150 Opening ASCII mode data connection for /bin/ls 

        C:
        150 ASCII data connection for /bin/ls (137.167.104.91,37445) (0 bytes).

        D:
        150 Opening ASCII mode data connection for /linux/fisk/kpanelrc (0.0.0.0,0) (545 bytes).
          
        E:
        125 Data connection already open; Transfer starting. */

      int size=-1; /* default unknown size */


      /*
       * It appears that there are FTP-servers that return size 0 for files
       * when SIZE is used on the file while being in BINARY mode. To work
       * around that (stupid) behavior, we attempt to parse the RETR response
       * even if the SIZE returned size zero.
       *
       * Debugging help from Salvatore Sorrentino on February 26, 2003.
       */

      if(!dirlist &&
         !data->set.ftp_ascii &&
         (downloadsize < 1)) {
        /*
         * It seems directory listings either don't show the size or very
         * often uses size 0 anyway. ASCII transfers may very well turn out
         * that the transfered amount of data is not the same as this line
         * tells, why using this number in those cases only confuses us.
         *
         * Example D above makes this parsing a little tricky */
        char *bytes;
        bytes=strstr(buf, " bytes");
        if(bytes--) {
          int in=bytes-buf;
          /* this is a hint there is size information in there! ;-) */
          while(--in) {
            /* scan for the parenthesis and break there */
            if('(' == *bytes)
              break;
            /* if only skip digits, or else we're in deep trouble */
            if(!isdigit((int)*bytes)) {
              bytes=NULL;
              break;
            }
            /* one more estep backwards */
            bytes--;
          }
          /* only if we have nothing but digits: */
          if(bytes++) {
            /* get the number! */
            size = atoi(bytes);
          }
            
        }
      }
      else if(downloadsize > -1)
        size = downloadsize;

      if(data->set.ftp_use_port) {
        result = AllowServerConnect(data, conn, conn->secondarysocket);
        if( result )
          return result;
      }

      infof(data, "Getting file with size: %d\n", size);

      /* FTP download: */
      result=Curl_Transfer(conn, conn->secondarysocket, size, FALSE,
                           bytecountp,
                           -1, NULL); /* no upload here */
      if(result)
        return result;
    }
    else {
      if(dirlist && (ftpcode == 450)) {
        /* simply no matching files */
        ftp->no_transfer = TRUE; /* don't think we should download anything */
      }
      else {
        failf(data, "%s", buf+4);
        return CURLE_FTP_COULDNT_RETR_FILE;
      }
    }
	
  }
  /* end of transfer */

  return CURLE_OK;
}

/***********************************************************************
 *
 * ftp_perform()
 *
 * This is the actual DO function for FTP. Get a file/directory according to
 * the options previously setup.
 */

static
CURLcode ftp_perform(struct connectdata *conn,
                     bool *connected)  /* for the TCP connect status after
                                          PASV / PORT */
{
  /* this is FTP and no proxy */
  CURLcode result=CURLE_OK;
  struct SessionHandle *data=conn->data;
  char *buf = data->state.buffer; /* this is our buffer */

  /* the ftp struct is already inited in Curl_ftp_connect() */
  struct FTP *ftp = conn->proto.ftp;

  /* Send any QUOTE strings? */
  if(data->set.quote) {
    if ((result = ftp_sendquote(conn, data->set.quote)) != CURLE_OK)
      return result;
  }