include/linux/netfilter_ipv4/ip_conntrack_tuple.h

   1 #ifndef _IP_CONNTRACK_TUPLE_H
   2 #define _IP_CONNTRACK_TUPLE_H
   3
   4 /* A `tuple' is a structure containing the information to uniquely
   5   identify a connection.  ie. if two packets have the same tuple, they
   6   are in the same connection; if not, they are not.
   7
   8   We divide the structure along "manipulatable" and
   9   "non-manipulatable" lines, for the benefit of the NAT code.
  10 */
  11
  12 /* The protocol-specific manipulable parts of the tuple: always in
  13    network order! */
  14 union ip_conntrack_manip_proto
  15 {
  16         /* Add other protocols here. */
  17         u_int16_t all;
  18
  19         struct {
  20                 u_int16_t port;
  21         } tcp;
  22         struct {
  23                 u_int16_t port;
  24         } udp;
  25         struct {
  26                 u_int16_t id;
  27         } icmp;
  28         struct {
  29                 u_int16_t port;
  30         } sctp;
  31         struct {
  32                 u_int16_t key;  /* key is 32bit, pptp only uses 16 */
  33         } gre;
  34 };
  35
  36 /* The manipulable part of the tuple. */
  37 struct ip_conntrack_manip
  38 {
  39         u_int32_t ip;
  40         union ip_conntrack_manip_proto u;
  41 };
  42
  43 /* This contains the information to distinguish a connection. */
  44 struct ip_conntrack_tuple
  45 {
  46         struct ip_conntrack_manip src;
  47
  48         /* These are the parts of the tuple which are fixed. */
  49         struct {
  50                 u_int32_t ip;
  51                 union {
  52                         /* Add other protocols here. */
  53                         u_int16_t all;
  54
  55                         struct {
  56                                 u_int16_t port;
  57                         } tcp;
  58                         struct {
  59                                 u_int16_t port;
  60                         } udp;
  61                         struct {
  62                                 u_int8_t type, code;
  63                         } icmp;
  64                         struct {
  65                                 u_int16_t port;
  66                         } sctp;
  67                         struct {
  68                                 u_int16_t key;  /* key is 32bit,
  69                                                  * pptp only uses 16 */
  70                         } gre;
  71                 } u;
  72
  73                 /* The protocol. */
  74                 u_int8_t protonum;
  75
  76                 /* The direction (for tuplehash) */
  77                 u_int8_t dir;
  78         } dst;
  79 };
  80
  81 /* This is optimized opposed to a memset of the whole structure.  Everything we
  82  * really care about is the  source/destination unions */
  83 #define IP_CT_TUPLE_U_BLANK(tuple)                              \
  84         do {                                                    \
  85                 (tuple)->src.u.all = 0;                         \
  86                 (tuple)->dst.u.all = 0;                         \
  87         } while (0)
  88
  89 enum ip_conntrack_dir
  90 {
  91         IP_CT_DIR_ORIGINAL,
  92         IP_CT_DIR_REPLY,
  93         IP_CT_DIR_MAX
  94 };
  95
  96 #ifdef __KERNEL__
  97
  98 #define DUMP_TUPLE(tp)                                          \
  99 DEBUGP("tuple %p: %u %u.%u.%u.%u:%hu -> %u.%u.%u.%u:%hu\n",     \
 100        (tp), (tp)->dst.protonum,                                \
 101        NIPQUAD((tp)->src.ip), ntohs((tp)->src.u.all),           \
 102        NIPQUAD((tp)->dst.ip), ntohs((tp)->dst.u.all))
 103
 104 #define CTINFO2DIR(ctinfo) ((ctinfo) >= IP_CT_IS_REPLY ? IP_CT_DIR_REPLY : IP_CT_DIR_ORIGINAL)
 105
 106 /* If we're the first tuple, it's the original dir. */
 107 #define DIRECTION(h) ((enum ip_conntrack_dir)(h)->tuple.dst.dir)
 108
 109 /* Connections have two entries in the hash table: one for each way */
 110 struct ip_conntrack_tuple_hash
 111 {
 112         struct list_head list;
 113
 114         struct ip_conntrack_tuple tuple;
 115 };
 116
 117 #endif /* __KERNEL__ */
 118
 119 static inline int ip_ct_tuple_src_equal(const struct ip_conntrack_tuple *t1,
 120                                         const struct ip_conntrack_tuple *t2)
 121 {
 122         return t1->src.ip == t2->src.ip
 123                 && t1->src.u.all == t2->src.u.all;
 124 }
 125
 126 static inline int ip_ct_tuple_dst_equal(const struct ip_conntrack_tuple *t1,
 127                                         const struct ip_conntrack_tuple *t2)
 128 {
 129         return t1->dst.ip == t2->dst.ip
 130                 && t1->dst.u.all == t2->dst.u.all
 131                 && t1->dst.protonum == t2->dst.protonum;
 132 }
 133
 134 static inline int ip_ct_tuple_equal(const struct ip_conntrack_tuple *t1,
 135                                     const struct ip_conntrack_tuple *t2)
 136 {
 137         return ip_ct_tuple_src_equal(t1, t2) && ip_ct_tuple_dst_equal(t1, t2);
 138 }
 139
 140 static inline int ip_ct_tuple_mask_cmp(const struct ip_conntrack_tuple *t,
 141                                        const struct ip_conntrack_tuple *tuple,
 142                                        const struct ip_conntrack_tuple *mask)
 143 {
 144         return !(((t->src.ip ^ tuple->src.ip) & mask->src.ip)
 145                  || ((t->dst.ip ^ tuple->dst.ip) & mask->dst.ip)
 146                  || ((t->src.u.all ^ tuple->src.u.all) & mask->src.u.all)
 147                  || ((t->dst.u.all ^ tuple->dst.u.all) & mask->dst.u.all)
 148                  || ((t->dst.protonum ^ tuple->dst.protonum)
 149                      & mask->dst.protonum));
 150 }
 151
 152 #endif /* _IP_CONNTRACK_TUPLE_H */