-peer review
[oweals/gnunet.git] / src / include / gnunet_tun_lib.h
index 61eb8638919c5ce7dc6bcd76c3add9e09807126b..3bb1ea359a97689c435a69210dae09147872c7cb 100644 (file)
@@ -70,19 +70,56 @@ struct GNUNET_TUN_Layer2PacketHeader
  */
 struct GNUNET_TUN_IPv4Header
 {
-  unsigned header_length:4 GNUNET_PACKED;
-  unsigned version:4 GNUNET_PACKED;
+#if __BYTE_ORDER == __LITTLE_ENDIAN
+  unsigned int header_length:4 GNUNET_PACKED;
+  unsigned int version:4 GNUNET_PACKED;
+#elif __BYTE_ORDER == __BIG_ENDIAN
+  unsigned int version:4 GNUNET_PACKED;
+  unsigned int header_length:4 GNUNET_PACKED;
+#else
+  #error byteorder undefined
+#endif
   uint8_t diff_serv;
+
+  /**
+   * Length of the packet, including this header.
+   */
   uint16_t total_length GNUNET_PACKED;
+  
+  /**
+   * Unique random ID for matching up fragments.
+   */
   uint16_t identification GNUNET_PACKED;
-  unsigned flags:3 GNUNET_PACKED;
-  unsigned fragmentation_offset:13 GNUNET_PACKED;
+
+  unsigned int flags:3 GNUNET_PACKED;
+
+  unsigned int fragmentation_offset:13 GNUNET_PACKED;
+
+  /**
+   * How many more hops can this packet be forwarded?
+   */
   uint8_t ttl;
+
+  /**
+   * L4-protocol, for example, IPPROTO_UDP or IPPROTO_TCP.
+   */
   uint8_t protocol;
+
+  /**
+   * Checksum.
+   */
   uint16_t checksum GNUNET_PACKED;
+
+  /**
+   * Origin of the packet.
+   */ 
   struct in_addr source_address GNUNET_PACKED;
+
+  /**
+   * Destination of the packet.
+   */ 
   struct in_addr destination_address GNUNET_PACKED;
-};
+} GNUNET_GCC_STRUCT_LAYOUT;
 
 
 /**
@@ -90,55 +127,113 @@ struct GNUNET_TUN_IPv4Header
  */
 struct GNUNET_TUN_IPv6Header
 {
-  unsigned traffic_class_h:4 GNUNET_PACKED;
-  unsigned version:4 GNUNET_PACKED;
-  unsigned traffic_class_l:4 GNUNET_PACKED;
-  unsigned flow_label:20 GNUNET_PACKED;
+#if __BYTE_ORDER == __LITTLE_ENDIAN
+  unsigned int traffic_class_h:4 GNUNET_PACKED;
+  unsigned int version:4 GNUNET_PACKED;
+  unsigned int traffic_class_l:4 GNUNET_PACKED;
+  unsigned int flow_label:20 GNUNET_PACKED;
+#elif __BYTE_ORDER == __BIG_ENDIAN
+  unsigned int version:4 GNUNET_PACKED;
+  unsigned int traffic_class:8 GNUNET_PACKED;
+  unsigned int flow_label:20 GNUNET_PACKED;
+#else
+  #error byteorder undefined
+#endif
+  /**
+   * Length of the payload, excluding this header.
+   */
   uint16_t payload_length GNUNET_PACKED;
+
+  /**
+   * For example, IPPROTO_UDP or IPPROTO_TCP.
+   */
   uint8_t next_header;
+
+  /**
+   * How many more hops can this packet be forwarded?
+   */
   uint8_t hop_limit;
+
+  /**
+   * Origin of the packet.
+   */ 
   struct in6_addr source_address GNUNET_PACKED;
+
+  /**
+   * Destination of the packet.
+   */ 
   struct in6_addr destination_address GNUNET_PACKED;
-};
+} GNUNET_GCC_STRUCT_LAYOUT;
 
 
 /**
- * TCP packet header (FIXME: rename!)
+ * TCP packet header.
  */
 struct GNUNET_TUN_TcpHeader
 {
-  unsigned spt:16 GNUNET_PACKED;
-  unsigned dpt:16 GNUNET_PACKED;
-  unsigned seq:32 GNUNET_PACKED;
-  unsigned ack:32 GNUNET_PACKED;
+  uint16_t source_port GNUNET_PACKED;
+  uint16_t destination_port GNUNET_PACKED;
+
+  /**
+   * Sequence number.
+   */
+  uint32_t seq GNUNET_PACKED;
+
+  /**
+   * Acknowledgement number.
+   */
+  uint32_t ack GNUNET_PACKED;
+#if __BYTE_ORDER == __LITTLE_ENDIAN
   /**
-   * Reserved.
+   * Reserved.  Must be zero.
    */
-  unsigned rsv:4 GNUNET_PACKED;
+  unsigned int reserved : 4 GNUNET_PACKED;
   /**
    * Number of 32-bit words in TCP header.
    */
-  unsigned off:4 GNUNET_PACKED;
-  unsigned flg:8 GNUNET_PACKED;
+  unsigned int off : 4 GNUNET_PACKED;
+#elif __BYTE_ORDER == __BIG_ENDIAN
+  /**
+   * Number of 32-bit words in TCP header.
+   */
+  unsigned int off : 4 GNUNET_PACKED;
+  /**
+   * Reserved.  Must be zero.
+   */
+  unsigned int reserved : 4 GNUNET_PACKED;
+#else
+  #error byteorder undefined
+#endif        
+
+  /**
+   * Flags (SYN, FIN, ACK, etc.)
+   */
+  uint8_t flags;
+
   /**
    * Window size.
    */
-  unsigned wsz:16 GNUNET_PACKED;
-  unsigned crc:16 GNUNET_PACKED;
+  uint16_t window_size GNUNET_PACKED;
+
+  /**
+   * Checksum.
+   */
+  uint16_t crc GNUNET_PACKED;
+
   /**
    * Urgent pointer.
    */
-  unsigned urg:16 GNUNET_PACKED;
-};
+  uint16_t urgent_pointer GNUNET_PACKED;
+} GNUNET_GCC_STRUCT_LAYOUT;
 
 
 /**
- * UDP packet header  (FIXME: rename!)
+ * UDP packet header.
  */
 struct GNUNET_TUN_UdpHeader
 {
-  uint16_t spt GNUNET_PACKED;
-  uint16_t dpt GNUNET_PACKED;
+  uint16_t source_port GNUNET_PACKED;
+  uint16_t destination_port GNUNET_PACKED;
   uint16_t len GNUNET_PACKED;
   uint16_t crc GNUNET_PACKED;
 };
@@ -173,6 +268,7 @@ struct GNUNET_TUN_DnsHeader
 #define        GNUNET_TUN_ICMPTYPE6_ECHO_REQUEST 128
 #define        GNUNET_TUN_ICMPTYPE6_ECHO_REPLY 129
 
+
 /**
  * ICMP header.
  */