ftp.c

    for (modeoff = 0; mode[modeoff]; modeoff++) {
      ftpsendf(data->firstsocket, conn, mode[modeoff]);
      nread = Curl_GetFTPResponse(data->firstsocket, buf, conn, &ftpcode);
      if(nread < 0)
	return CURLE_OPERATION_TIMEOUTED;

      if (ftpcode == results[modeoff])
	break;
    }

    if (!mode[modeoff]) {
      failf(data, "Odd return code after PASV");
      return CURLE_FTP_WEIRD_PASV_REPLY;
    }
    else if (strcmp(mode[modeoff], "PASV") == 0) {
      int ip[4];
      int port[2];
      unsigned short newport; /* remote port, not necessary the local one */
      unsigned short connectport; /* the local port connect() should use! */
      char newhost[32];
#ifdef ENABLE_IPV6
      struct addrinfo *res;
#else
      struct hostent *he;
#endif
      char *str=buf,*ip_addr;
      char *hostdataptr=NULL;

      /*
       * 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]);
      newport = (port[0]<<8) + port[1];
      if(data->bits.httpproxy) {
        /*
         * This is a tunnel through a http proxy and we need to connect to the
         * proxy again here. We already have the name info for it since the
         * previous lookup.
         */
#ifdef ENABLE_IPV6
        res = conn->res;
#else
        he = conn->hp;
#endif
        connectport =
          (unsigned short)data->port; /* we connect to the proxy's port */
      }
      else {
        /* normal, direct, ftp connection */
#ifdef ENABLE_IPV6
        res = Curl_getaddrinfo(data, newhost, newport);
        if(!res)
#else
        he = Curl_gethost(data, newhost, &hostdataptr);
        if(!he)
#endif
        {
          failf(data, "Can't resolve new host %s", newhost);
          return CURLE_FTP_CANT_GET_HOST;
        }
        connectport = newport; /* we connect to the remote port */
      }
	
#ifdef ENABLE_IPV6
      data->secondarysocket = -1;
      for (ai = res; ai; ai = ai->ai_next) {
	/* XXX for now, we can do IPv4 only */
	if (ai->ai_family != AF_INET)
	  continue;

	data->secondarysocket = socket(ai->ai_family, ai->ai_socktype,
	    ai->ai_protocol);
	if (data->secondarysocket < 0)
	  continue;

	if(data->bits.verbose) {
	  char hbuf[NI_MAXHOST];
	  char nbuf[NI_MAXHOST];
	  char sbuf[NI_MAXSERV];
#ifdef NI_WITHSCOPEID
	  const int niflags = NI_NUMERICHOST | NI_NUMERICSERV | NI_WITHSCOPEID;
#else
	  const int niflags = NI_NUMERICHOST | NI_NUMERICSERV;
#endif
	  if (getnameinfo(res->ai_addr, res->ai_addrlen, nbuf, sizeof(nbuf),
	      sbuf, sizeof(sbuf), niflags)) {
	    snprintf(nbuf, sizeof(nbuf), "?");
	    snprintf(sbuf, sizeof(sbuf), "?");
	  }
	  if (getnameinfo(res->ai_addr, res->ai_addrlen, hbuf, sizeof(hbuf),
	      NULL, 0, 0)) {
	    infof(data, "Connecting to %s port %s\n", nbuf, sbuf);
	  } else {
	    infof(data, "Connecting to %s (%s) port %s\n", hbuf, nbuf, sbuf);
	  }
	}

	if (connect(data->secondarysocket, ai->ai_addr, ai->ai_addrlen) < 0) {
	  close(data->secondarysocket);
	  data->secondarysocket = -1;
	  continue;
	}

	break;
      }

      if (data->secondarysocket < 0) {
	failf(data, strerror(errno));
        return CURLE_FTP_CANT_RECONNECT;
      }
#else
      data->secondarysocket = socket(AF_INET, SOCK_STREAM, 0);

      memset((char *) &serv_addr, '\0', sizeof(serv_addr));
      memcpy((char *)&(serv_addr.sin_addr), he->h_addr, he->h_length);
      serv_addr.sin_family = he->h_addrtype;

      serv_addr.sin_port = htons(connectport);

      if(data->bits.verbose) {
        struct in_addr in;
        struct hostent * answer;

#if defined(HAVE_INET_ADDR)
        unsigned long address;
# if defined(HAVE_GETHOSTBYADDR_R)
        int h_errnop;
# endif

        address = inet_addr(newhost);
# ifdef HAVE_GETHOSTBYADDR_R

#  ifdef HAVE_GETHOSTBYADDR_R_5
        /* AIX, Digital Unix style:
           extern int gethostbyaddr_r(char *addr, size_t len, int type,
           struct hostent *htent, struct hostent_data *ht_data); */

        /* Fred Noz helped me try this out, now it at least compiles! */

        if(gethostbyaddr_r((char *) &address,
                           sizeof(address), AF_INET,
                           (struct hostent *)hostent_buf,
                           hostent_buf + sizeof(*answer)))
           answer=NULL;
                           
#  endif
#  ifdef HAVE_GETHOSTBYADDR_R_7
        /* Solaris and IRIX */
        answer = gethostbyaddr_r((char *) &address, sizeof(address), AF_INET,
                                 (struct hostent *)hostent_buf,
                                 hostent_buf + sizeof(*answer),
                                 sizeof(hostent_buf) - sizeof(*answer),
                                 &h_errnop);
#  endif
#  ifdef HAVE_GETHOSTBYADDR_R_8
        /* Linux style */
        if(gethostbyaddr_r((char *) &address, sizeof(address), AF_INET,
                           (struct hostent *)hostent_buf,
                           hostent_buf + sizeof(*answer),
                           sizeof(hostent_buf) - sizeof(*answer),
                           &answer,
                           &h_errnop))
           answer=NULL; /* error */
#  endif
        
# else
        answer = gethostbyaddr((char *) &address, sizeof(address), AF_INET);
# endif
#else
        answer = NULL;
#endif
        (void) memcpy(&in.s_addr, *he->h_addr_list, sizeof (in.s_addr));
        infof(data, "Connecting to %s (%s) port %u\n",
              answer?answer->h_name:newhost,
#if defined(HAVE_INET_NTOA_R)
              inet_ntoa_r(in, ip_addr=ntoa_buf, sizeof(ntoa_buf)),
#else
              ip_addr = inet_ntoa(in),
#endif
              connectport);
      }
	
      if(hostdataptr)
        free(hostdataptr);

      if (connect(data->secondarysocket, (struct sockaddr *) &serv_addr,
                  sizeof(serv_addr)) < 0) {
        switch(errno) {
#ifdef ECONNREFUSED
          /* this should be made nicer */
        case ECONNREFUSED:
          failf(data, "Connection refused by ftp server");
          break;
#endif
#ifdef EINTR
        case EINTR:
          failf(data, "Connection timeouted to ftp server");
          break;
#endif
        default:
          failf(data, "Can't connect to ftp server");
          break;
        }
        return CURLE_FTP_CANT_RECONNECT;
      }
#endif /*ENABLE_IPV6*/

      if (data->bits.tunnel_thru_httpproxy) {
        /* We want "seamless" FTP operations through HTTP proxy tunnel */
        result = Curl_ConnectHTTPProxyTunnel(conn, data->secondarysocket,
                                             newhost, newport);
        if(CURLE_OK != result)
          return result;
      }
    } else {
      return CURLE_FTP_CANT_RECONNECT;
    }
  }
  /* we have the (new) data connection ready */
  infof(data, "Connected the data stream!\n");

  if(data->bits.upload) {

    /* Set type to binary (unless specified ASCII) */
    ftpsendf(data->firstsocket, conn, "TYPE %s",
          (data->bits.ftp_ascii)?"A":"I");

    nread = Curl_GetFTPResponse(data->firstsocket, buf, conn, &ftpcode);
    if(nread < 0)
      return CURLE_OPERATION_TIMEOUTED;

    if(ftpcode != 200) {
      failf(data, "Couldn't set %s mode",
            (data->bits.ftp_ascii)?"ASCII":"binary");
      return (data->bits.ftp_ascii)? CURLE_FTP_COULDNT_SET_ASCII:
        CURLE_FTP_COULDNT_SET_BINARY;
    }

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

        ftpsendf(data->firstsocket, conn, "SIZE %s", ftp->file);

        nread = Curl_GetFTPResponse(data->firstsocket, buf, conn, &ftpcode);
        if(nread < 0)
          return CURLE_OPERATION_TIMEOUTED;

        if(ftpcode != 213) {
          failf(data, "Couldn't get file size: %s", buf+4);
          return CURLE_FTP_COULDNT_GET_SIZE;
        }

        /* get the size from the ascii string: */
        data->resume_from = atoi(buf+4);
      }

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

          if(readthisamountnow > BUFSIZE)
            readthisamountnow = BUFSIZE;

          actuallyread =
            data->fread(data->buffer, 1, readthisamountnow, data->in);

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

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

          if(data->infilesize <= 0) {
            failf(data, "File already completely uploaded\n");
            return CURLE_FTP_COULDNT_STOR_FILE;
          }
        }
        /* we've passed, proceed as normal */
      }
    }

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

    nread = Curl_GetFTPResponse(data->firstsocket, buf, conn, &ftpcode);
    if(nread < 0)
      return CURLE_OPERATION_TIMEOUTED;

    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->bits.ftp_use_port) {
      result = AllowServerConnect(data, portsock);
      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->infilesize);

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

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

      from=strtol(data->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 - */
        data->resume_from = from;
        infof(data, "FTP RANGE %d to end of file\n", from);
      }
      else if(from < 0) {
        /* -Y */
        totalsize = -from;
        data->maxdownload = -from;
        data->resume_from = from;
        infof(data, "FTP RANGE the last %d bytes\n", totalsize);
      }
      else {
        /* X-Y */
        totalsize = to-from;
        data->maxdownload = totalsize+1; /* include the last mentioned byte */
        data->resume_from = from;
        infof(data, "FTP RANGE from %d getting %d bytes\n", from, data->maxdownload);
      }
      infof(data, "range-download from %d to %d, totally %d bytes\n",
            from, to, totalsize);
    }

    if((data->bits.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 */
      ftpsendf(data->firstsocket, conn, "TYPE A");
	
      nread = Curl_GetFTPResponse(data->firstsocket, buf, conn, &ftpcode);
      if(nread < 0)
        return CURLE_OPERATION_TIMEOUTED;
	
      if(ftpcode != 200) {
        failf(data, "Couldn't set ascii mode");
        return CURLE_FTP_COULDNT_SET_ASCII;
      }

      /* 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(data->firstsocket, conn, "%s",
            data->customrequest?data->customrequest:
            (data->bits.ftp_list_only?"NLST":"LIST"));
    }
    else {
      /* Set type to binary (unless specified ASCII) */
      ftpsendf(data->firstsocket, conn, "TYPE %s",
               (data->bits.ftp_ascii)?"A":"I");

      nread = Curl_GetFTPResponse(data->firstsocket, buf, conn, &ftpcode);
      if(nread < 0)
        return CURLE_OPERATION_TIMEOUTED;

      if(ftpcode != 200) {
        failf(data, "Couldn't set %s mode",
              (data->bits.ftp_ascii)?"ASCII":"binary");
        return (data->bits.ftp_ascii)? CURLE_FTP_COULDNT_SET_ASCII:
          CURLE_FTP_COULDNT_SET_BINARY;
      }

      if(data->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.  */

        ftpsendf(data->firstsocket, conn, "SIZE %s", ftp->file);

        nread = Curl_GetFTPResponse(data->firstsocket, buf, conn, &ftpcode);
        if(nread < 0)
          return CURLE_OPERATION_TIMEOUTED;

        if(ftpcode != 213) {
          infof(data, "server doesn't support SIZE: %s", buf+4);
          /* 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 {
          int foundsize=atoi(buf+4);
          /* 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(data->resume_from< 0) {
            /* We're supposed to download the last abs(from) bytes */
            if(foundsize < -data->resume_from) {
              failf(data, "Offset (%d) was beyond file size (%d)",
                    data->resume_from, foundsize);
              return CURLE_FTP_BAD_DOWNLOAD_RESUME;
            }
            /* convert to size to download */
            downloadsize = -data->resume_from;
            /* download from where? */
            data->resume_from = foundsize - downloadsize;
          }
          else {
            if(foundsize <= data->resume_from) {
              failf(data, "Offset (%d) was beyond file size (%d)",
                    data->resume_from, foundsize);
              return CURLE_FTP_BAD_DOWNLOAD_RESUME;
            }
            /* Now store the number of bytes we are expected to download */
            downloadsize = foundsize-data->resume_from;
          }
        }

        /* Set resume file transfer offset */
        infof(data, "Instructs server to resume from offset %d\n",
              data->resume_from);

        ftpsendf(data->firstsocket, conn, "REST %d", data->resume_from);

        nread = Curl_GetFTPResponse(data->firstsocket, buf, conn, &ftpcode);
        if(nread < 0)
          return CURLE_OPERATION_TIMEOUTED;

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

      ftpsendf(data->firstsocket, conn, "RETR %s", ftp->file);
    }

    nread = Curl_GetFTPResponse(data->firstsocket, buf, conn, &ftpcode);
    if(nread < 0)
      return CURLE_OPERATION_TIMEOUTED;

    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 */

      if(!dirlist &&
         !data->bits.ftp_ascii &&
         (-1 == downloadsize)) {
        /*
         * 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 index=bytes-buf;
          /* this is a hint there is size information in there! ;-) */
          while(--index) {
            /* 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->bits.ftp_use_port) {
        result = AllowServerConnect(data, portsock);
        if( result )
          return result;
      }

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

      /* FTP download: */
      result=Curl_Transfer(conn, data->secondarysocket, size, FALSE,
                      bytecountp,
                      -1, NULL); /* no upload here */
      if(result)
        return result;
    }
    else {
      failf(data, "%s", buf+4);
      return CURLE_FTP_COULDNT_RETR_FILE;
    }
	
  }
  /* end of transfer */

  return CURLE_OK;
}

/* -- deal with the ftp server!  -- */

/* argument is already checked for validity */
CURLcode Curl_ftp(struct connectdata *conn)
{
  CURLcode retcode;

  struct UrlData *data = conn->data;
  struct FTP *ftp;
  int dirlength=0; /* 0 forces strlen() */

  /* the ftp struct is already inited in ftp_connect() */
  ftp = data->proto.ftp;

  /* We split the path into dir and file parts *before* we URLdecode
     it */
  ftp->file = strrchr(conn->ppath, '/');
  if(ftp->file) {
    if(ftp->file != conn->ppath)
      dirlength=ftp->file-conn->ppath; /* don't count the traling slash */

    ftp->file++; /* point to the first letter in the file name part or
                    remain NULL */
  }
  else {
    ftp->file = conn->ppath; /* there's only a file part */
  }

  if(*ftp->file) {
    ftp->file = curl_unescape(ftp->file, 0);
    if(NULL == ftp->file) {
      failf(data, "no memory");
      return CURLE_OUT_OF_MEMORY;
    }
  }
  else
    ftp->file=NULL; /* instead of point to a zero byte, we make it a NULL
                       pointer */

  ftp->urlpath = conn->ppath;
  if(dirlength) {
    ftp->dir = curl_unescape(ftp->urlpath, dirlength);
    if(NULL == ftp->dir) {
      if(ftp->file)
        free(ftp->file);
      failf(data, "no memory");
      return CURLE_OUT_OF_MEMORY; /* failure */
    }
  }
  else
    ftp->dir = NULL;

  retcode = _ftp(conn);

  /* clean up here, success or error doesn't matter */
  if(ftp->file)
    free(ftp->file);
  if(ftp->dir)
    free(ftp->dir);

  ftp->file = ftp->dir = NULL; /* zero */

  return retcode;
}

/*
 * ftpsendf() sends the formated string as a ftp command to a ftp server
 *
 * NOTE: we build the command in a fixed-length buffer, which sets length
 * restrictions on the command!
 *
 */
size_t Curl_ftpsendf(int fd, struct connectdata *conn, char *fmt, ...)
{
  size_t bytes_written;
  char s[256];

  va_list ap;
  va_start(ap, fmt);
  vsnprintf(s, 250, fmt, ap);
  va_end(ap);

  if(conn->data->bits.verbose)
    fprintf(conn->data->err, "> %s\n", s);

  strcat(s, "\r\n"); /* append a trailing CRLF */

#ifdef KRB4
  if(conn->sec_complete && conn->data->cmdchannel) {
    bytes_written = sec_fprintf(conn, conn->data->cmdchannel, s);
    fflush(conn->data->cmdchannel);
  }
  else
#endif /* KRB4 */
    {
      bytes_written = swrite(fd, s, strlen(s));
    }
  return(bytes_written);
}