コード例 #1
0
ファイル: packets.c プロジェクト: tvon/freeciv-web
/**************************************************************************
  ...
**************************************************************************/
void check_packet(struct data_in *din, struct connection *pc)
{
  size_t rem = dio_input_remaining(din);

  if (din->bad_string || din->bad_bit_string || rem != 0) {
    char from[MAX_LEN_ADDR + MAX_LEN_NAME + 128];
    int type, len;

    assert(pc != NULL);
    my_snprintf(from, sizeof(from), " from %s", conn_description(pc));

    dio_input_rewind(din);
    dio_get_uint16(din, &len);
    dio_get_uint8(din, &type);

    if (din->bad_string) {
      freelog(LOG_ERROR,
	      "received bad string in packet (type %d, len %d)%s",
	      type, len, from);
    }

    if (din->bad_bit_string) {
      freelog(LOG_ERROR,
	      "received bad bit string in packet (type %d, len %d)%s",
	      type, len, from);
    }

    if (din->too_short) {
      freelog(LOG_ERROR, "received short packet (type %d, len %d)%s",
	      type, len, from);
    }

    if (rem > 0) {
      /* This may be ok, eg a packet from a newer version with extra info
       * which we should just ignore */
      freelog(LOG_VERBOSE,
	      "received long packet (type %d, len %d, rem %lu)%s", type,
	      len, (unsigned long)rem, from);
    }
  }
}
コード例 #2
0
ファイル: packets.c プロジェクト: 4nakin/freeciv-android
/**************************************************************************
presult indicates if there is more packets in the cache. We return result
instead of just testing if the returning package is NULL as we sometimes
return a NULL packet even if everything is OK (receive_packet_goto_route).
**************************************************************************/
void *get_packet_from_connection(struct connection *pc,
				 enum packet_type *ptype, bool * presult)
{
  int len_read;
  int whole_packet_len;
  struct {
    enum packet_type type;
    int itype;
  } utype;
  struct data_in din;
#ifdef USE_COMPRESSION
  bool compressed_packet = FALSE;
  int header_size = 0;
#endif

  *presult = FALSE;

  if (!pc->used) {
    return NULL;		/* connection was closed, stop reading */
  }
  
  if (pc->buffer->ndata < 3) {
    return NULL;           /* length and type not read */
  }

  dio_input_init(&din, pc->buffer->data, pc->buffer->ndata);
  dio_get_uint16(&din, &len_read);

  /* The non-compressed case */
  whole_packet_len = len_read;

#ifdef USE_COMPRESSION
  if (len_read == JUMBO_SIZE) {
    compressed_packet = TRUE;
    header_size = 6;
    if (dio_input_remaining(&din) >= 4) {
      dio_get_uint32(&din, &whole_packet_len);
      log_compress("COMPRESS: got a jumbo packet of size %d",
                   whole_packet_len);
    } else {
      /* to return NULL below */
      whole_packet_len = 6;
    }
  } else if (len_read >= COMPRESSION_BORDER) {
    compressed_packet = TRUE;
    header_size = 2;
    whole_packet_len = len_read - COMPRESSION_BORDER;
    log_compress("COMPRESS: got a normal packet of size %d",
                 whole_packet_len);
  }
#endif

  if ((unsigned)whole_packet_len > pc->buffer->ndata) {
    return NULL;		/* not all data has been read */
  }

#ifdef USE_COMPRESSION
  if (compressed_packet) {
    uLong compressed_size = whole_packet_len - header_size;
    /* 
     * We don't know the decompressed size. We assume a bad case
     * here: an expansion by an factor of 100. 
     */
    unsigned long int decompressed_size = 100 * compressed_size;
    void *decompressed = fc_malloc(decompressed_size);
    int error;
    struct socket_packet_buffer *buffer = pc->buffer;
    
    error =
	uncompress(decompressed, &decompressed_size,
		   ADD_TO_POINTER(buffer->data, header_size), 
		   compressed_size);
    if (error != Z_OK) {
      log_verbose("Uncompressing of the packet stream failed. "
                  "The connection will be closed now.");
      connection_close(pc, _("decoding error"));
      return NULL;
    }

    buffer->ndata -= whole_packet_len;
    /* 
     * Remove the packet with the compressed data and shift all the
     * remaining data to the front. 
     */
    memmove(buffer->data, buffer->data + whole_packet_len, buffer->ndata);

    if (buffer->ndata + decompressed_size > buffer->nsize) {
      buffer->nsize += decompressed_size;
      buffer->data = fc_realloc(buffer->data, buffer->nsize);
    }

    /*
     * Make place for the uncompressed data by moving the remaining
     * data.
     */
    memmove(buffer->data + decompressed_size, buffer->data, buffer->ndata);

    /* 
     * Copy the uncompressed data.
     */
    memcpy(buffer->data, decompressed, decompressed_size);

    free(decompressed);

    buffer->ndata += decompressed_size;
    
    log_compress("COMPRESS: decompressed %ld into %ld",
                 compressed_size, decompressed_size);

    return get_packet_from_connection(pc, ptype, presult);
  }
#endif

  /*
   * At this point the packet is a plain uncompressed one. These have
   * to have to be at least 3 bytes in size.
   */
  if (whole_packet_len < 3) {
    log_verbose("The packet stream is corrupt. The connection "
                "will be closed now.");
    connection_close(pc, _("decoding error"));
    return NULL;
  }

  dio_get_uint8(&din, &utype.itype);

  utype.type = utype.itype;

  log_packet("got packet type=(%s)%d len=%d from %s",
             packet_name(utype.type), utype.itype, whole_packet_len,
             is_server() ? pc->username : "******");

  *ptype = utype.type;
  *presult = TRUE;

  if (pc->incoming_packet_notify) {
    pc->incoming_packet_notify(pc, utype.type, whole_packet_len);
  }

#if PACKET_SIZE_STATISTICS 
  {
    static struct {
      int counter;
      int size;
    } packets_stats[PACKET_LAST];
    static int packet_counter = 0;

    int packet_type = utype.itype;
    int size = whole_packet_len;

    if (!packet_counter) {
      int i;

      for (i = 0; i < PACKET_LAST; i++) {
	packets_stats[i].counter = 0;
	packets_stats[i].size = 0;
      }
    }

    packets_stats[packet_type].counter++;
    packets_stats[packet_type].size += size;

    packet_counter++;
    if (packet_counter % 100 == 0) {
      int i, sum = 0;

      log_test("Received packets:");
      for (i = 0; i < PACKET_LAST; i++) {
	if (packets_stats[i].counter == 0)
	  continue;
	sum += packets_stats[i].size;
        log_test("  [%-25.25s %3d]: %6d packets; %8d bytes total; "
                 "%5d bytes/packet average",
                 packet_name(i), i, packets_stats[i].counter,
                 packets_stats[i].size,
                 packets_stats[i].size / packets_stats[i].counter);
      }
      log_test("received %d bytes in %d packets;average size "
               "per packet %d bytes",
               sum, packet_counter, sum / packet_counter);
    }
  }
#endif
  return get_packet_from_connection_helper(pc, utype.type);
}