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