1 #ifndef _NF_FLOW_TABLE_H
2 #define _NF_FLOW_TABLE_H
3 
4 #include <linux/in.h>
5 #include <linux/in6.h>
6 #include <linux/netdevice.h>
7 #include <linux/rhashtable-types.h>
8 #include <linux/rcupdate.h>
9 #include <linux/netfilter.h>
10 #include <linux/netfilter/nf_conntrack_tuple_common.h>
11 #include <net/flow_offload.h>
12 #include <net/dst.h>
13 #include <linux/if_pppox.h>
14 #include <linux/ppp_defs.h>
15 
16 struct nf_flowtable;
17 struct nf_flow_rule;
18 struct flow_offload;
19 enum flow_offload_tuple_dir;
20 
21 struct nf_flow_key {
22 	struct flow_dissector_key_meta			meta;
23 	struct flow_dissector_key_control		control;
24 	struct flow_dissector_key_control		enc_control;
25 	struct flow_dissector_key_basic			basic;
26 	struct flow_dissector_key_vlan			vlan;
27 	struct flow_dissector_key_vlan			cvlan;
28 	union {
29 		struct flow_dissector_key_ipv4_addrs	ipv4;
30 		struct flow_dissector_key_ipv6_addrs	ipv6;
31 	};
32 	struct flow_dissector_key_keyid			enc_key_id;
33 	union {
34 		struct flow_dissector_key_ipv4_addrs	enc_ipv4;
35 		struct flow_dissector_key_ipv6_addrs	enc_ipv6;
36 	};
37 	struct flow_dissector_key_tcp			tcp;
38 	struct flow_dissector_key_ports			tp;
39 } __aligned(BITS_PER_LONG / 8); /* Ensure that we can do comparisons as longs. */
40 
41 struct nf_flow_match {
42 	struct flow_dissector	dissector;
43 	struct nf_flow_key	key;
44 	struct nf_flow_key	mask;
45 };
46 
47 struct nf_flow_rule {
48 	struct nf_flow_match	match;
49 	struct flow_rule	*rule;
50 };
51 
52 struct nf_flowtable_type {
53 	struct list_head		list;
54 	int				family;
55 	int				(*init)(struct nf_flowtable *ft);
56 	bool				(*gc)(const struct flow_offload *flow);
57 	int				(*setup)(struct nf_flowtable *ft,
58 						 struct net_device *dev,
59 						 enum flow_block_command cmd);
60 	int				(*action)(struct net *net,
61 						  struct flow_offload *flow,
62 						  enum flow_offload_tuple_dir dir,
63 						  struct nf_flow_rule *flow_rule);
64 	void				(*free)(struct nf_flowtable *ft);
65 	nf_hookfn			*hook;
66 	struct module			*owner;
67 };
68 
69 enum nf_flowtable_flags {
70 	NF_FLOWTABLE_HW_OFFLOAD		= 0x1,	/* NFT_FLOWTABLE_HW_OFFLOAD */
71 	NF_FLOWTABLE_COUNTER		= 0x2,	/* NFT_FLOWTABLE_COUNTER */
72 };
73 
74 struct nf_flowtable {
75 	struct list_head		list;
76 	struct rhashtable		rhashtable;
77 	int				priority;
78 	const struct nf_flowtable_type	*type;
79 	struct delayed_work		gc_work;
80 	unsigned int			flags;
81 	struct flow_block		flow_block;
82 	struct rw_semaphore		flow_block_lock; /* Guards flow_block */
83 	possible_net_t			net;
84 };
85 
86 static inline bool nf_flowtable_hw_offload(struct nf_flowtable *flowtable)
87 {
88 	return flowtable->flags & NF_FLOWTABLE_HW_OFFLOAD;
89 }
90 
91 enum flow_offload_tuple_dir {
92 	FLOW_OFFLOAD_DIR_ORIGINAL = IP_CT_DIR_ORIGINAL,
93 	FLOW_OFFLOAD_DIR_REPLY = IP_CT_DIR_REPLY,
94 };
95 #define FLOW_OFFLOAD_DIR_MAX	IP_CT_DIR_MAX
96 
97 enum flow_offload_xmit_type {
98 	FLOW_OFFLOAD_XMIT_UNSPEC	= 0,
99 	FLOW_OFFLOAD_XMIT_NEIGH,
100 	FLOW_OFFLOAD_XMIT_XFRM,
101 	FLOW_OFFLOAD_XMIT_DIRECT,
102 	FLOW_OFFLOAD_XMIT_TC,
103 };
104 
105 #define NF_FLOW_TABLE_ENCAP_MAX		2
106 
107 struct flow_offload_tuple {
108 	union {
109 		struct in_addr		src_v4;
110 		struct in6_addr		src_v6;
111 	};
112 	union {
113 		struct in_addr		dst_v4;
114 		struct in6_addr		dst_v6;
115 	};
116 	struct {
117 		__be16			src_port;
118 		__be16			dst_port;
119 	};
120 
121 	int				iifidx;
122 
123 	u8				l3proto;
124 	u8				l4proto;
125 	struct {
126 		u16			id;
127 		__be16			proto;
128 	} encap[NF_FLOW_TABLE_ENCAP_MAX];
129 
130 	/* All members above are keys for lookups, see flow_offload_hash(). */
131 	struct { }			__hash;
132 
133 	u8				dir:2,
134 					xmit_type:3,
135 					encap_num:2,
136 					in_vlan_ingress:2;
137 	u16				mtu;
138 	union {
139 		struct {
140 			struct dst_entry *dst_cache;
141 			u32		dst_cookie;
142 		};
143 		struct {
144 			u32		ifidx;
145 			u32		hw_ifidx;
146 			u8		h_source[ETH_ALEN];
147 			u8		h_dest[ETH_ALEN];
148 		} out;
149 		struct {
150 			u32		iifidx;
151 		} tc;
152 	};
153 };
154 
155 struct flow_offload_tuple_rhash {
156 	struct rhash_head		node;
157 	struct flow_offload_tuple	tuple;
158 };
159 
160 enum nf_flow_flags {
161 	NF_FLOW_SNAT,
162 	NF_FLOW_DNAT,
163 	NF_FLOW_TEARDOWN,
164 	NF_FLOW_HW,
165 	NF_FLOW_HW_DYING,
166 	NF_FLOW_HW_DEAD,
167 	NF_FLOW_HW_PENDING,
168 	NF_FLOW_HW_BIDIRECTIONAL,
169 	NF_FLOW_HW_ESTABLISHED,
170 };
171 
172 enum flow_offload_type {
173 	NF_FLOW_OFFLOAD_UNSPEC	= 0,
174 	NF_FLOW_OFFLOAD_ROUTE,
175 };
176 
177 struct flow_offload {
178 	struct flow_offload_tuple_rhash		tuplehash[FLOW_OFFLOAD_DIR_MAX];
179 	struct nf_conn				*ct;
180 	unsigned long				flags;
181 	u16					type;
182 	u32					timeout;
183 	struct rcu_head				rcu_head;
184 };
185 
186 #define NF_FLOW_TIMEOUT (30 * HZ)
187 #define nf_flowtable_time_stamp	(u32)jiffies
188 
189 unsigned long flow_offload_get_timeout(struct flow_offload *flow);
190 
191 static inline __s32 nf_flow_timeout_delta(unsigned int timeout)
192 {
193 	return (__s32)(timeout - nf_flowtable_time_stamp);
194 }
195 
196 struct nf_flow_route {
197 	struct {
198 		struct dst_entry		*dst;
199 		struct {
200 			u32			ifindex;
201 			struct {
202 				u16		id;
203 				__be16		proto;
204 			} encap[NF_FLOW_TABLE_ENCAP_MAX];
205 			u8			num_encaps:2,
206 						ingress_vlans:2;
207 		} in;
208 		struct {
209 			u32			ifindex;
210 			u32			hw_ifindex;
211 			u8			h_source[ETH_ALEN];
212 			u8			h_dest[ETH_ALEN];
213 		} out;
214 		enum flow_offload_xmit_type	xmit_type;
215 	} tuple[FLOW_OFFLOAD_DIR_MAX];
216 };
217 
218 struct flow_offload *flow_offload_alloc(struct nf_conn *ct);
219 void flow_offload_free(struct flow_offload *flow);
220 
221 static inline int
222 nf_flow_table_offload_add_cb(struct nf_flowtable *flow_table,
223 			     flow_setup_cb_t *cb, void *cb_priv)
224 {
225 	struct flow_block *block = &flow_table->flow_block;
226 	struct flow_block_cb *block_cb;
227 	int err = 0;
228 
229 	down_write(&flow_table->flow_block_lock);
230 	block_cb = flow_block_cb_lookup(block, cb, cb_priv);
231 	if (block_cb) {
232 		err = -EEXIST;
233 		goto unlock;
234 	}
235 
236 	block_cb = flow_block_cb_alloc(cb, cb_priv, cb_priv, NULL);
237 	if (IS_ERR(block_cb)) {
238 		err = PTR_ERR(block_cb);
239 		goto unlock;
240 	}
241 
242 	list_add_tail(&block_cb->list, &block->cb_list);
243 
244 unlock:
245 	up_write(&flow_table->flow_block_lock);
246 	return err;
247 }
248 
249 static inline void
250 nf_flow_table_offload_del_cb(struct nf_flowtable *flow_table,
251 			     flow_setup_cb_t *cb, void *cb_priv)
252 {
253 	struct flow_block *block = &flow_table->flow_block;
254 	struct flow_block_cb *block_cb;
255 
256 	down_write(&flow_table->flow_block_lock);
257 	block_cb = flow_block_cb_lookup(block, cb, cb_priv);
258 	if (block_cb) {
259 		list_del(&block_cb->list);
260 		flow_block_cb_free(block_cb);
261 	} else {
262 		WARN_ON(true);
263 	}
264 	up_write(&flow_table->flow_block_lock);
265 }
266 
267 void flow_offload_route_init(struct flow_offload *flow,
268 			     const struct nf_flow_route *route);
269 
270 int flow_offload_add(struct nf_flowtable *flow_table, struct flow_offload *flow);
271 void flow_offload_refresh(struct nf_flowtable *flow_table,
272 			  struct flow_offload *flow, bool force);
273 
274 struct flow_offload_tuple_rhash *flow_offload_lookup(struct nf_flowtable *flow_table,
275 						     struct flow_offload_tuple *tuple);
276 void nf_flow_table_gc_run(struct nf_flowtable *flow_table);
277 void nf_flow_table_gc_cleanup(struct nf_flowtable *flowtable,
278 			      struct net_device *dev);
279 void nf_flow_table_cleanup(struct net_device *dev);
280 
281 int nf_flow_table_init(struct nf_flowtable *flow_table);
282 void nf_flow_table_free(struct nf_flowtable *flow_table);
283 
284 void flow_offload_teardown(struct flow_offload *flow);
285 
286 void nf_flow_snat_port(const struct flow_offload *flow,
287 		       struct sk_buff *skb, unsigned int thoff,
288 		       u8 protocol, enum flow_offload_tuple_dir dir);
289 void nf_flow_dnat_port(const struct flow_offload *flow,
290 		       struct sk_buff *skb, unsigned int thoff,
291 		       u8 protocol, enum flow_offload_tuple_dir dir);
292 
293 struct flow_ports {
294 	__be16 source, dest;
295 };
296 
297 unsigned int nf_flow_offload_ip_hook(void *priv, struct sk_buff *skb,
298 				     const struct nf_hook_state *state);
299 unsigned int nf_flow_offload_ipv6_hook(void *priv, struct sk_buff *skb,
300 				       const struct nf_hook_state *state);
301 
302 #define MODULE_ALIAS_NF_FLOWTABLE(family)	\
303 	MODULE_ALIAS("nf-flowtable-" __stringify(family))
304 
305 void nf_flow_offload_add(struct nf_flowtable *flowtable,
306 			 struct flow_offload *flow);
307 void nf_flow_offload_del(struct nf_flowtable *flowtable,
308 			 struct flow_offload *flow);
309 void nf_flow_offload_stats(struct nf_flowtable *flowtable,
310 			   struct flow_offload *flow);
311 
312 void nf_flow_table_offload_flush(struct nf_flowtable *flowtable);
313 void nf_flow_table_offload_flush_cleanup(struct nf_flowtable *flowtable);
314 
315 int nf_flow_table_offload_setup(struct nf_flowtable *flowtable,
316 				struct net_device *dev,
317 				enum flow_block_command cmd);
318 int nf_flow_rule_route_ipv4(struct net *net, struct flow_offload *flow,
319 			    enum flow_offload_tuple_dir dir,
320 			    struct nf_flow_rule *flow_rule);
321 int nf_flow_rule_route_ipv6(struct net *net, struct flow_offload *flow,
322 			    enum flow_offload_tuple_dir dir,
323 			    struct nf_flow_rule *flow_rule);
324 
325 int nf_flow_table_offload_init(void);
326 void nf_flow_table_offload_exit(void);
327 
328 static inline __be16 nf_flow_pppoe_proto(const struct sk_buff *skb)
329 {
330 	__be16 proto;
331 
332 	proto = *((__be16 *)(skb_mac_header(skb) + ETH_HLEN +
333 			     sizeof(struct pppoe_hdr)));
334 	switch (proto) {
335 	case htons(PPP_IP):
336 		return htons(ETH_P_IP);
337 	case htons(PPP_IPV6):
338 		return htons(ETH_P_IPV6);
339 	}
340 
341 	return 0;
342 }
343 
344 #define NF_FLOW_TABLE_STAT_INC(net, count) __this_cpu_inc((net)->ft.stat->count)
345 #define NF_FLOW_TABLE_STAT_DEC(net, count) __this_cpu_dec((net)->ft.stat->count)
346 #define NF_FLOW_TABLE_STAT_INC_ATOMIC(net, count)	\
347 	this_cpu_inc((net)->ft.stat->count)
348 #define NF_FLOW_TABLE_STAT_DEC_ATOMIC(net, count)	\
349 	this_cpu_dec((net)->ft.stat->count)
350 
351 #ifdef CONFIG_NF_FLOW_TABLE_PROCFS
352 int nf_flow_table_init_proc(struct net *net);
353 void nf_flow_table_fini_proc(struct net *net);
354 #else
355 static inline int nf_flow_table_init_proc(struct net *net)
356 {
357 	return 0;
358 }
359 
360 static inline void nf_flow_table_fini_proc(struct net *net)
361 {
362 }
363 #endif /* CONFIG_NF_FLOW_TABLE_PROCFS */
364 
365 #endif /* _NF_FLOW_TABLE_H */
366