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. */
29 struct 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. */
37 struct 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 
75 struct nf_conntrack_tuple_mask {
76 	struct {
77 		union nf_inet_addr u3;
78 		union nf_conntrack_man_proto u;
79 	} src;
80 };
81 
82 static 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 
92 static 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 
102 static 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 */
119 struct nf_conntrack_tuple_hash {
120 	struct hlist_nulls_node hnnode;
121 	struct nf_conntrack_tuple tuple;
122 };
123 
124 static 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 
132 static 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 
140 static 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 
147 static inline bool
148 nf_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 
155 static inline bool
156 nf_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 
178 static inline bool
179 nf_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