xref: /linux/include/net/flow.h (revision 95db3b255fde4e830e5f8cc011eb404023f669d4)
1 /*
2  *
3  *	Generic internet FLOW.
4  *
5  */
6 
7 #ifndef _NET_FLOW_H
8 #define _NET_FLOW_H
9 
10 #include <linux/socket.h>
11 #include <linux/in6.h>
12 #include <linux/atomic.h>
13 #include <net/flow_dissector.h>
14 
15 /*
16  * ifindex generation is per-net namespace, and loopback is
17  * always the 1st device in ns (see net_dev_init), thus any
18  * loopback device should get ifindex 1
19  */
20 
21 #define LOOPBACK_IFINDEX	1
22 
23 struct flowi_tunnel {
24 	__be64			tun_id;
25 };
26 
27 struct flowi_common {
28 	int	flowic_oif;
29 	int	flowic_iif;
30 	__u32	flowic_mark;
31 	__u8	flowic_tos;
32 	__u8	flowic_scope;
33 	__u8	flowic_proto;
34 	__u8	flowic_flags;
35 #define FLOWI_FLAG_ANYSRC		0x01
36 #define FLOWI_FLAG_KNOWN_NH		0x02
37 #define FLOWI_FLAG_L3MDEV_SRC		0x04
38 #define FLOWI_FLAG_SKIP_NH_OIF		0x08
39 	__u32	flowic_secid;
40 	struct flowi_tunnel flowic_tun_key;
41 };
42 
43 union flowi_uli {
44 	struct {
45 		__be16	dport;
46 		__be16	sport;
47 	} ports;
48 
49 	struct {
50 		__u8	type;
51 		__u8	code;
52 	} icmpt;
53 
54 	struct {
55 		__le16	dport;
56 		__le16	sport;
57 	} dnports;
58 
59 	__be32		spi;
60 	__be32		gre_key;
61 
62 	struct {
63 		__u8	type;
64 	} mht;
65 };
66 
67 struct flowi4 {
68 	struct flowi_common	__fl_common;
69 #define flowi4_oif		__fl_common.flowic_oif
70 #define flowi4_iif		__fl_common.flowic_iif
71 #define flowi4_mark		__fl_common.flowic_mark
72 #define flowi4_tos		__fl_common.flowic_tos
73 #define flowi4_scope		__fl_common.flowic_scope
74 #define flowi4_proto		__fl_common.flowic_proto
75 #define flowi4_flags		__fl_common.flowic_flags
76 #define flowi4_secid		__fl_common.flowic_secid
77 #define flowi4_tun_key		__fl_common.flowic_tun_key
78 
79 	/* (saddr,daddr) must be grouped, same order as in IP header */
80 	__be32			saddr;
81 	__be32			daddr;
82 
83 	union flowi_uli		uli;
84 #define fl4_sport		uli.ports.sport
85 #define fl4_dport		uli.ports.dport
86 #define fl4_icmp_type		uli.icmpt.type
87 #define fl4_icmp_code		uli.icmpt.code
88 #define fl4_ipsec_spi		uli.spi
89 #define fl4_mh_type		uli.mht.type
90 #define fl4_gre_key		uli.gre_key
91 } __attribute__((__aligned__(BITS_PER_LONG/8)));
92 
93 static inline void flowi4_init_output(struct flowi4 *fl4, int oif,
94 				      __u32 mark, __u8 tos, __u8 scope,
95 				      __u8 proto, __u8 flags,
96 				      __be32 daddr, __be32 saddr,
97 				      __be16 dport, __be16 sport)
98 {
99 	fl4->flowi4_oif = oif;
100 	fl4->flowi4_iif = LOOPBACK_IFINDEX;
101 	fl4->flowi4_mark = mark;
102 	fl4->flowi4_tos = tos;
103 	fl4->flowi4_scope = scope;
104 	fl4->flowi4_proto = proto;
105 	fl4->flowi4_flags = flags;
106 	fl4->flowi4_secid = 0;
107 	fl4->flowi4_tun_key.tun_id = 0;
108 	fl4->daddr = daddr;
109 	fl4->saddr = saddr;
110 	fl4->fl4_dport = dport;
111 	fl4->fl4_sport = sport;
112 }
113 
114 /* Reset some input parameters after previous lookup */
115 static inline void flowi4_update_output(struct flowi4 *fl4, int oif, __u8 tos,
116 					__be32 daddr, __be32 saddr)
117 {
118 	fl4->flowi4_oif = oif;
119 	fl4->flowi4_tos = tos;
120 	fl4->daddr = daddr;
121 	fl4->saddr = saddr;
122 }
123 
124 
125 struct flowi6 {
126 	struct flowi_common	__fl_common;
127 #define flowi6_oif		__fl_common.flowic_oif
128 #define flowi6_iif		__fl_common.flowic_iif
129 #define flowi6_mark		__fl_common.flowic_mark
130 #define flowi6_scope		__fl_common.flowic_scope
131 #define flowi6_proto		__fl_common.flowic_proto
132 #define flowi6_flags		__fl_common.flowic_flags
133 #define flowi6_secid		__fl_common.flowic_secid
134 #define flowi6_tun_key		__fl_common.flowic_tun_key
135 	struct in6_addr		daddr;
136 	struct in6_addr		saddr;
137 	/* Note: flowi6_tos is encoded in flowlabel, too. */
138 	__be32			flowlabel;
139 	union flowi_uli		uli;
140 #define fl6_sport		uli.ports.sport
141 #define fl6_dport		uli.ports.dport
142 #define fl6_icmp_type		uli.icmpt.type
143 #define fl6_icmp_code		uli.icmpt.code
144 #define fl6_ipsec_spi		uli.spi
145 #define fl6_mh_type		uli.mht.type
146 #define fl6_gre_key		uli.gre_key
147 } __attribute__((__aligned__(BITS_PER_LONG/8)));
148 
149 struct flowidn {
150 	struct flowi_common	__fl_common;
151 #define flowidn_oif		__fl_common.flowic_oif
152 #define flowidn_iif		__fl_common.flowic_iif
153 #define flowidn_mark		__fl_common.flowic_mark
154 #define flowidn_scope		__fl_common.flowic_scope
155 #define flowidn_proto		__fl_common.flowic_proto
156 #define flowidn_flags		__fl_common.flowic_flags
157 	__le16			daddr;
158 	__le16			saddr;
159 	union flowi_uli		uli;
160 #define fld_sport		uli.ports.sport
161 #define fld_dport		uli.ports.dport
162 } __attribute__((__aligned__(BITS_PER_LONG/8)));
163 
164 struct flowi {
165 	union {
166 		struct flowi_common	__fl_common;
167 		struct flowi4		ip4;
168 		struct flowi6		ip6;
169 		struct flowidn		dn;
170 	} u;
171 #define flowi_oif	u.__fl_common.flowic_oif
172 #define flowi_iif	u.__fl_common.flowic_iif
173 #define flowi_mark	u.__fl_common.flowic_mark
174 #define flowi_tos	u.__fl_common.flowic_tos
175 #define flowi_scope	u.__fl_common.flowic_scope
176 #define flowi_proto	u.__fl_common.flowic_proto
177 #define flowi_flags	u.__fl_common.flowic_flags
178 #define flowi_secid	u.__fl_common.flowic_secid
179 #define flowi_tun_key	u.__fl_common.flowic_tun_key
180 } __attribute__((__aligned__(BITS_PER_LONG/8)));
181 
182 static inline struct flowi *flowi4_to_flowi(struct flowi4 *fl4)
183 {
184 	return container_of(fl4, struct flowi, u.ip4);
185 }
186 
187 static inline struct flowi *flowi6_to_flowi(struct flowi6 *fl6)
188 {
189 	return container_of(fl6, struct flowi, u.ip6);
190 }
191 
192 static inline struct flowi *flowidn_to_flowi(struct flowidn *fldn)
193 {
194 	return container_of(fldn, struct flowi, u.dn);
195 }
196 
197 typedef unsigned long flow_compare_t;
198 
199 static inline size_t flow_key_size(u16 family)
200 {
201 	switch (family) {
202 	case AF_INET:
203 		BUILD_BUG_ON(sizeof(struct flowi4) % sizeof(flow_compare_t));
204 		return sizeof(struct flowi4) / sizeof(flow_compare_t);
205 	case AF_INET6:
206 		BUILD_BUG_ON(sizeof(struct flowi6) % sizeof(flow_compare_t));
207 		return sizeof(struct flowi6) / sizeof(flow_compare_t);
208 	case AF_DECnet:
209 		BUILD_BUG_ON(sizeof(struct flowidn) % sizeof(flow_compare_t));
210 		return sizeof(struct flowidn) / sizeof(flow_compare_t);
211 	}
212 	return 0;
213 }
214 
215 #define FLOW_DIR_IN	0
216 #define FLOW_DIR_OUT	1
217 #define FLOW_DIR_FWD	2
218 
219 struct net;
220 struct sock;
221 struct flow_cache_ops;
222 
223 struct flow_cache_object {
224 	const struct flow_cache_ops *ops;
225 };
226 
227 struct flow_cache_ops {
228 	struct flow_cache_object *(*get)(struct flow_cache_object *);
229 	int (*check)(struct flow_cache_object *);
230 	void (*delete)(struct flow_cache_object *);
231 };
232 
233 typedef struct flow_cache_object *(*flow_resolve_t)(
234 		struct net *net, const struct flowi *key, u16 family,
235 		u8 dir, struct flow_cache_object *oldobj, void *ctx);
236 
237 struct flow_cache_object *flow_cache_lookup(struct net *net,
238 					    const struct flowi *key, u16 family,
239 					    u8 dir, flow_resolve_t resolver,
240 					    void *ctx);
241 int flow_cache_init(struct net *net);
242 void flow_cache_fini(struct net *net);
243 
244 void flow_cache_flush(struct net *net);
245 void flow_cache_flush_deferred(struct net *net);
246 extern atomic_t flow_cache_genid;
247 
248 __u32 __get_hash_from_flowi6(const struct flowi6 *fl6, struct flow_keys *keys);
249 
250 static inline __u32 get_hash_from_flowi6(const struct flowi6 *fl6)
251 {
252 	struct flow_keys keys;
253 
254 	return __get_hash_from_flowi6(fl6, &keys);
255 }
256 
257 __u32 __get_hash_from_flowi4(const struct flowi4 *fl4, struct flow_keys *keys);
258 
259 static inline __u32 get_hash_from_flowi4(const struct flowi4 *fl4)
260 {
261 	struct flow_keys keys;
262 
263 	return __get_hash_from_flowi4(fl4, &keys);
264 }
265 
266 #endif
267