/include/net/netfilter/nf_conntrack_tuple.h

  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 protocol-specific manipulable parts of the tuple: always in
 28   network order! */
 29union nf_conntrack_man_proto {
 30	/* Add other protocols here. */
 31	__be16 all;
 32
 33	struct {
 34		__be16 port;
 35	} tcp;
 36	struct {
 37		__be16 port;
 38	} udp;
 39	struct {
 40		__be16 id;
 41	} icmp;
 42	struct {
 43		__be16 port;
 44	} dccp;
 45	struct {
 46		__be16 port;
 47	} sctp;
 48	struct {
 49		__be16 key;	/* GRE key is 32bit, PPtP only uses 16bit */
 50	} gre;
 51};
 52
 53/* The manipulable part of the tuple. */
 54struct nf_conntrack_man {
 55	union nf_inet_addr u3;
 56	union nf_conntrack_man_proto u;
 57	/* Layer 3 protocol */
 58	u_int16_t l3num;
 59};
 60
 61/* This contains the information to distinguish a connection. */
 62struct nf_conntrack_tuple {
 63	struct nf_conntrack_man src;
 64
 65	/* These are the parts of the tuple which are fixed. */
 66	struct {
 67		union nf_inet_addr u3;
 68		union {
 69			/* Add other protocols here. */
 70			__be16 all;
 71
 72			struct {
 73				__be16 port;
 74			} tcp;
 75			struct {
 76				__be16 port;
 77			} udp;
 78			struct {
 79				u_int8_t type, code;
 80			} icmp;
 81			struct {
 82				__be16 port;
 83			} dccp;
 84			struct {
 85				__be16 port;
 86			} sctp;
 87			struct {
 88				__be16 key;
 89			} gre;
 90		} u;
 91
 92		/* The protocol. */
 93		u_int8_t protonum;
 94
 95		/* The direction (for tuplehash) */
 96		u_int8_t dir;
 97	} dst;
 98};
 99
100struct nf_conntrack_tuple_mask {
101	struct {
102		union nf_inet_addr u3;
103		union nf_conntrack_man_proto u;
104	} src;
105};
106
107#ifdef __KERNEL__
108
109static inline void nf_ct_dump_tuple_ip(const struct nf_conntrack_tuple *t)
110{
111#ifdef DEBUG
112	printk("tuple %p: %u %pI4:%hu -> %pI4:%hu\n",
113	       t, t->dst.protonum,
114	       &t->src.u3.ip, ntohs(t->src.u.all),
115	       &t->dst.u3.ip, ntohs(t->dst.u.all));
116#endif
117}
118
119static inline void nf_ct_dump_tuple_ipv6(const struct nf_conntrack_tuple *t)
120{
121#ifdef DEBUG
122	printk("tuple %p: %u %pI6 %hu -> %pI6 %hu\n",
123	       t, t->dst.protonum,
124	       t->src.u3.all, ntohs(t->src.u.all),
125	       t->dst.u3.all, ntohs(t->dst.u.all));
126#endif
127}
128
129static inline void nf_ct_dump_tuple(const struct nf_conntrack_tuple *t)
130{
131	switch (t->src.l3num) {
132	case AF_INET:
133		nf_ct_dump_tuple_ip(t);
134		break;
135	case AF_INET6:
136		nf_ct_dump_tuple_ipv6(t);
137		break;
138	}
139}
140
141/* If we're the first tuple, it's the original dir. */
142#define NF_CT_DIRECTION(h)						\
143	((enum ip_conntrack_dir)(h)->tuple.dst.dir)
144
145/* Connections have two entries in the hash table: one for each way */
146struct nf_conntrack_tuple_hash {
147	struct hlist_nulls_node hnnode;
148	struct nf_conntrack_tuple tuple;
149};
150
151#endif /* __KERNEL__ */
152
153static inline bool __nf_ct_tuple_src_equal(const struct nf_conntrack_tuple *t1,
154					   const struct nf_conntrack_tuple *t2)
155{ 
156	return (nf_inet_addr_cmp(&t1->src.u3, &t2->src.u3) &&
157		t1->src.u.all == t2->src.u.all &&
158		t1->src.l3num == t2->src.l3num);
159}
160
161static inline bool __nf_ct_tuple_dst_equal(const struct nf_conntrack_tuple *t1,
162					   const struct nf_conntrack_tuple *t2)
163{
164	return (nf_inet_addr_cmp(&t1->dst.u3, &t2->dst.u3) &&
165		t1->dst.u.all == t2->dst.u.all &&
166		t1->dst.protonum == t2->dst.protonum);
167}
168
169static inline bool nf_ct_tuple_equal(const struct nf_conntrack_tuple *t1,
170				     const struct nf_conntrack_tuple *t2)
171{
172	return __nf_ct_tuple_src_equal(t1, t2) &&
173	       __nf_ct_tuple_dst_equal(t1, t2);
174}
175
176static inline bool
177nf_ct_tuple_mask_equal(const struct nf_conntrack_tuple_mask *m1,
178		       const struct nf_conntrack_tuple_mask *m2)
179{
180	return (nf_inet_addr_cmp(&m1->src.u3, &m2->src.u3) &&
181		m1->src.u.all == m2->src.u.all);
182}
183
184static inline bool
185nf_ct_tuple_src_mask_cmp(const struct nf_conntrack_tuple *t1,
186			 const struct nf_conntrack_tuple *t2,
187			 const struct nf_conntrack_tuple_mask *mask)
188{
189	int count;
190
191	for (count = 0; count < NF_CT_TUPLE_L3SIZE; count++) {
192		if ((t1->src.u3.all[count] ^ t2->src.u3.all[count]) &
193		    mask->src.u3.all[count])
194			return false;
195	}
196
197	if ((t1->src.u.all ^ t2->src.u.all) & mask->src.u.all)
198		return false;
199
200	if (t1->src.l3num != t2->src.l3num ||
201	    t1->dst.protonum != t2->dst.protonum)
202		return false;
203
204	return true;
205}
206
207static inline bool
208nf_ct_tuple_mask_cmp(const struct nf_conntrack_tuple *t,
209		     const struct nf_conntrack_tuple *tuple,
210		     const struct nf_conntrack_tuple_mask *mask)
211{
212	return nf_ct_tuple_src_mask_cmp(t, tuple, mask) &&
213	       __nf_ct_tuple_dst_equal(t, tuple);
214}
215
216#endif /* _NF_CONNTRACK_TUPLE_H */