LXR linux/include/net/netfilter/nf_conntrack

   1/* SPDX-License-Identifier: GPL-2.0 */
   2/*
   3 * Definitions and Declarations for tuple.
   4 *
   5 * 16 Dec 2003: Yasuyuki Kozakai @USAGI <yasuyuki.kozakai@toshiba.co.jp>
   6 *      - generalize L3 protocol dependent part.
   7 *
   8 * Derived from include/linux/netfiter_ipv4/ip_conntrack_tuple.h
   9 */
  10
  11#ifndef _NF_CONNTRACK_TUPLE_H
  12#define _NF_CONNTRACK_TUPLE_H
  13
  14#include <linux/netfilter/x_tables.h>
  15#include <linux/netfilter/nf_conntrack_tuple_common.h>
  16#include <linux/list_nulls.h>
  17
  18/* A `tuple' is a structure containing the information to uniquely
  19  identify a connection.  ie. if two packets have the same tuple, they
  20  are in the same connection; if not, they are not.
  21
  22  We divide the structure along "manipulatable" and
  23  "non-manipulatable" lines, for the benefit of the NAT code.
  24*/
  25
  26#define NF_CT_TUPLE_L3SIZE      ARRAY_SIZE(((union nf_inet_addr *)NULL)->all)
  27
  28/* The manipulable part of the tuple. */
  29struct nf_conntrack_man {
  30        union nf_inet_addr u3;
  31        union nf_conntrack_man_proto u;
  32        /* Layer 3 protocol */
  33        u_int16_t l3num;
  34};
  35
  36/* This contains the information to distinguish a connection. */
  37struct nf_conntrack_tuple {
  38        struct nf_conntrack_man src;
  39
  40        /* These are the parts of the tuple which are fixed. */
  41        struct {
  42                union nf_inet_addr u3;
  43                union {
  44                        /* Add other protocols here. */
  45                        __be16 all;
  46
  47                        struct {
  48                                __be16 port;
  49                        } tcp;
  50                        struct {
  51                                __be16 port;
  52                        } udp;
  53                        struct {
  54                                u_int8_t type, code;
  55                        } icmp;
  56                        struct {
  57                                __be16 port;
  58                        } dccp;
  59                        struct {
  60                                __be16 port;
  61                        } sctp;
  62                        struct {
  63                                __be16 key;
  64                        } gre;
  65                } u;
  66
  67                /* The protocol. */
  68                u_int8_t protonum;
  69
  70                /* The direction (for tuplehash) */
  71                u_int8_t dir;
  72        } dst;
  73};
  74
  75struct nf_conntrack_tuple_mask {
  76        struct {
  77                union nf_inet_addr u3;
  78                union nf_conntrack_man_proto u;
  79        } src;
  80};
  81
  82static inline void nf_ct_dump_tuple_ip(const struct nf_conntrack_tuple *t)
  83{
  84#ifdef DEBUG
  85        printk("tuple %p: %u %pI4:%hu -> %pI4:%hu\n",
  86               t, t->dst.protonum,
  87               &t->src.u3.ip, ntohs(t->src.u.all),
  88               &t->dst.u3.ip, ntohs(t->dst.u.all));
  89#endif
  90}
  91
  92static inline void nf_ct_dump_tuple_ipv6(const struct nf_conntrack_tuple *t)
  93{
  94#ifdef DEBUG
  95        printk("tuple %p: %u %pI6 %hu -> %pI6 %hu\n",
  96               t, t->dst.protonum,
  97               t->src.u3.all, ntohs(t->src.u.all),
  98               t->dst.u3.all, ntohs(t->dst.u.all));
  99#endif
 100}
 101
 102static inline void nf_ct_dump_tuple(const struct nf_conntrack_tuple *t)
 103{
 104        switch (t->src.l3num) {
 105        case AF_INET:
 106                nf_ct_dump_tuple_ip(t);
 107                break;
 108        case AF_INET6:
 109                nf_ct_dump_tuple_ipv6(t);
 110                break;
 111        }
 112}
 113
 114/* If we're the first tuple, it's the original dir. */
 115#define NF_CT_DIRECTION(h)                                              \
 116        ((enum ip_conntrack_dir)(h)->tuple.dst.dir)
 117
 118/* Connections have two entries in the hash table: one for each way */
 119struct nf_conntrack_tuple_hash {
 120        struct hlist_nulls_node hnnode;
 121        struct nf_conntrack_tuple tuple;
 122};
 123
 124static inline bool __nf_ct_tuple_src_equal(const struct nf_conntrack_tuple *t1,
 125                                           const struct nf_conntrack_tuple *t2)
 126{ 
 127        return (nf_inet_addr_cmp(&t1->src.u3, &t2->src.u3) &&
 128                t1->src.u.all == t2->src.u.all &&
 129                t1->src.l3num == t2->src.l3num);
 130}
 131
 132static inline bool __nf_ct_tuple_dst_equal(const struct nf_conntrack_tuple *t1,
 133                                           const struct nf_conntrack_tuple *t2)
 134{
 135        return (nf_inet_addr_cmp(&t1->dst.u3, &t2->dst.u3) &&
 136                t1->dst.u.all == t2->dst.u.all &&
 137                t1->dst.protonum == t2->dst.protonum);
 138}
 139
 140static inline bool nf_ct_tuple_equal(const struct nf_conntrack_tuple *t1,
 141                                     const struct nf_conntrack_tuple *t2)
 142{
 143        return __nf_ct_tuple_src_equal(t1, t2) &&
 144               __nf_ct_tuple_dst_equal(t1, t2);
 145}
 146
 147static inline bool
 148nf_ct_tuple_mask_equal(const struct nf_conntrack_tuple_mask *m1,
 149                       const struct nf_conntrack_tuple_mask *m2)
 150{
 151        return (nf_inet_addr_cmp(&m1->src.u3, &m2->src.u3) &&
 152                m1->src.u.all == m2->src.u.all);
 153}
 154
 155static inline bool
 156nf_ct_tuple_src_mask_cmp(const struct nf_conntrack_tuple *t1,
 157                         const struct nf_conntrack_tuple *t2,
 158                         const struct nf_conntrack_tuple_mask *mask)
 159{
 160        int count;
 161
 162        for (count = 0; count < NF_CT_TUPLE_L3SIZE; count++) {
 163                if ((t1->src.u3.all[count] ^ t2->src.u3.all[count]) &
 164                    mask->src.u3.all[count])
 165                        return false;
 166        }
 167
 168        if ((t1->src.u.all ^ t2->src.u.all) & mask->src.u.all)
 169                return false;
 170
 171        if (t1->src.l3num != t2->src.l3num ||
 172            t1->dst.protonum != t2->dst.protonum)
 173                return false;
 174
 175        return true;
 176}
 177
 178static inline bool
 179nf_ct_tuple_mask_cmp(const struct nf_conntrack_tuple *t,
 180                     const struct nf_conntrack_tuple *tuple,
 181                     const struct nf_conntrack_tuple_mask *mask)
 182{
 183        return nf_ct_tuple_src_mask_cmp(t, tuple, mask) &&
 184               __nf_ct_tuple_dst_equal(t, tuple);
 185}
 186
 187#endif /* _NF_CONNTRACK_TUPLE_H */
 188