xref: /linux/include/net/flow.h (revision 93d90ad708b8da6efc0e487b66111aa9db7f70c7)
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 
14 /*
15  * ifindex generation is per-net namespace, and loopback is
16  * always the 1st device in ns (see net_dev_init), thus any
17  * loopback device should get ifindex 1
18  */
19 
20 #define LOOPBACK_IFINDEX	1
21 
22 struct flowi_common {
23 	int	flowic_oif;
24 	int	flowic_iif;
25 	__u32	flowic_mark;
26 	__u8	flowic_tos;
27 	__u8	flowic_scope;
28 	__u8	flowic_proto;
29 	__u8	flowic_flags;
30 #define FLOWI_FLAG_ANYSRC		0x01
31 #define FLOWI_FLAG_KNOWN_NH		0x02
32 	__u32	flowic_secid;
33 };
34 
35 union flowi_uli {
36 	struct {
37 		__be16	dport;
38 		__be16	sport;
39 	} ports;
40 
41 	struct {
42 		__u8	type;
43 		__u8	code;
44 	} icmpt;
45 
46 	struct {
47 		__le16	dport;
48 		__le16	sport;
49 	} dnports;
50 
51 	__be32		spi;
52 	__be32		gre_key;
53 
54 	struct {
55 		__u8	type;
56 	} mht;
57 };
58 
59 struct flowi4 {
60 	struct flowi_common	__fl_common;
61 #define flowi4_oif		__fl_common.flowic_oif
62 #define flowi4_iif		__fl_common.flowic_iif
63 #define flowi4_mark		__fl_common.flowic_mark
64 #define flowi4_tos		__fl_common.flowic_tos
65 #define flowi4_scope		__fl_common.flowic_scope
66 #define flowi4_proto		__fl_common.flowic_proto
67 #define flowi4_flags		__fl_common.flowic_flags
68 #define flowi4_secid		__fl_common.flowic_secid
69 
70 	/* (saddr,daddr) must be grouped, same order as in IP header */
71 	__be32			saddr;
72 	__be32			daddr;
73 
74 	union flowi_uli		uli;
75 #define fl4_sport		uli.ports.sport
76 #define fl4_dport		uli.ports.dport
77 #define fl4_icmp_type		uli.icmpt.type
78 #define fl4_icmp_code		uli.icmpt.code
79 #define fl4_ipsec_spi		uli.spi
80 #define fl4_mh_type		uli.mht.type
81 #define fl4_gre_key		uli.gre_key
82 } __attribute__((__aligned__(BITS_PER_LONG/8)));
83 
84 static inline void flowi4_init_output(struct flowi4 *fl4, int oif,
85 				      __u32 mark, __u8 tos, __u8 scope,
86 				      __u8 proto, __u8 flags,
87 				      __be32 daddr, __be32 saddr,
88 				      __be16 dport, __be16 sport)
89 {
90 	fl4->flowi4_oif = oif;
91 	fl4->flowi4_iif = LOOPBACK_IFINDEX;
92 	fl4->flowi4_mark = mark;
93 	fl4->flowi4_tos = tos;
94 	fl4->flowi4_scope = scope;
95 	fl4->flowi4_proto = proto;
96 	fl4->flowi4_flags = flags;
97 	fl4->flowi4_secid = 0;
98 	fl4->daddr = daddr;
99 	fl4->saddr = saddr;
100 	fl4->fl4_dport = dport;
101 	fl4->fl4_sport = sport;
102 }
103 
104 /* Reset some input parameters after previous lookup */
105 static inline void flowi4_update_output(struct flowi4 *fl4, int oif, __u8 tos,
106 					__be32 daddr, __be32 saddr)
107 {
108 	fl4->flowi4_oif = oif;
109 	fl4->flowi4_tos = tos;
110 	fl4->daddr = daddr;
111 	fl4->saddr = saddr;
112 }
113 
114 
115 struct flowi6 {
116 	struct flowi_common	__fl_common;
117 #define flowi6_oif		__fl_common.flowic_oif
118 #define flowi6_iif		__fl_common.flowic_iif
119 #define flowi6_mark		__fl_common.flowic_mark
120 #define flowi6_tos		__fl_common.flowic_tos
121 #define flowi6_scope		__fl_common.flowic_scope
122 #define flowi6_proto		__fl_common.flowic_proto
123 #define flowi6_flags		__fl_common.flowic_flags
124 #define flowi6_secid		__fl_common.flowic_secid
125 	struct in6_addr		daddr;
126 	struct in6_addr		saddr;
127 	__be32			flowlabel;
128 	union flowi_uli		uli;
129 #define fl6_sport		uli.ports.sport
130 #define fl6_dport		uli.ports.dport
131 #define fl6_icmp_type		uli.icmpt.type
132 #define fl6_icmp_code		uli.icmpt.code
133 #define fl6_ipsec_spi		uli.spi
134 #define fl6_mh_type		uli.mht.type
135 #define fl6_gre_key		uli.gre_key
136 } __attribute__((__aligned__(BITS_PER_LONG/8)));
137 
138 struct flowidn {
139 	struct flowi_common	__fl_common;
140 #define flowidn_oif		__fl_common.flowic_oif
141 #define flowidn_iif		__fl_common.flowic_iif
142 #define flowidn_mark		__fl_common.flowic_mark
143 #define flowidn_scope		__fl_common.flowic_scope
144 #define flowidn_proto		__fl_common.flowic_proto
145 #define flowidn_flags		__fl_common.flowic_flags
146 	__le16			daddr;
147 	__le16			saddr;
148 	union flowi_uli		uli;
149 #define fld_sport		uli.ports.sport
150 #define fld_dport		uli.ports.dport
151 } __attribute__((__aligned__(BITS_PER_LONG/8)));
152 
153 struct flowi {
154 	union {
155 		struct flowi_common	__fl_common;
156 		struct flowi4		ip4;
157 		struct flowi6		ip6;
158 		struct flowidn		dn;
159 	} u;
160 #define flowi_oif	u.__fl_common.flowic_oif
161 #define flowi_iif	u.__fl_common.flowic_iif
162 #define flowi_mark	u.__fl_common.flowic_mark
163 #define flowi_tos	u.__fl_common.flowic_tos
164 #define flowi_scope	u.__fl_common.flowic_scope
165 #define flowi_proto	u.__fl_common.flowic_proto
166 #define flowi_flags	u.__fl_common.flowic_flags
167 #define flowi_secid	u.__fl_common.flowic_secid
168 } __attribute__((__aligned__(BITS_PER_LONG/8)));
169 
170 static inline struct flowi *flowi4_to_flowi(struct flowi4 *fl4)
171 {
172 	return container_of(fl4, struct flowi, u.ip4);
173 }
174 
175 static inline struct flowi *flowi6_to_flowi(struct flowi6 *fl6)
176 {
177 	return container_of(fl6, struct flowi, u.ip6);
178 }
179 
180 static inline struct flowi *flowidn_to_flowi(struct flowidn *fldn)
181 {
182 	return container_of(fldn, struct flowi, u.dn);
183 }
184 
185 typedef unsigned long flow_compare_t;
186 
187 static inline size_t flow_key_size(u16 family)
188 {
189 	switch (family) {
190 	case AF_INET:
191 		BUILD_BUG_ON(sizeof(struct flowi4) % sizeof(flow_compare_t));
192 		return sizeof(struct flowi4) / sizeof(flow_compare_t);
193 	case AF_INET6:
194 		BUILD_BUG_ON(sizeof(struct flowi6) % sizeof(flow_compare_t));
195 		return sizeof(struct flowi6) / sizeof(flow_compare_t);
196 	case AF_DECnet:
197 		BUILD_BUG_ON(sizeof(struct flowidn) % sizeof(flow_compare_t));
198 		return sizeof(struct flowidn) / sizeof(flow_compare_t);
199 	}
200 	return 0;
201 }
202 
203 #define FLOW_DIR_IN	0
204 #define FLOW_DIR_OUT	1
205 #define FLOW_DIR_FWD	2
206 
207 struct net;
208 struct sock;
209 struct flow_cache_ops;
210 
211 struct flow_cache_object {
212 	const struct flow_cache_ops *ops;
213 };
214 
215 struct flow_cache_ops {
216 	struct flow_cache_object *(*get)(struct flow_cache_object *);
217 	int (*check)(struct flow_cache_object *);
218 	void (*delete)(struct flow_cache_object *);
219 };
220 
221 typedef struct flow_cache_object *(*flow_resolve_t)(
222 		struct net *net, const struct flowi *key, u16 family,
223 		u8 dir, struct flow_cache_object *oldobj, void *ctx);
224 
225 struct flow_cache_object *flow_cache_lookup(struct net *net,
226 					    const struct flowi *key, u16 family,
227 					    u8 dir, flow_resolve_t resolver,
228 					    void *ctx);
229 int flow_cache_init(struct net *net);
230 void flow_cache_fini(struct net *net);
231 
232 void flow_cache_flush(struct net *net);
233 void flow_cache_flush_deferred(struct net *net);
234 extern atomic_t flow_cache_genid;
235 
236 #endif
237