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 	void				(*get)(struct nf_flowtable *ft);
66 	void				(*put)(struct nf_flowtable *ft);
67 	nf_hookfn			*hook;
68 	struct module			*owner;
69 };
70 
71 enum nf_flowtable_flags {
72 	NF_FLOWTABLE_HW_OFFLOAD		= 0x1,	/* NFT_FLOWTABLE_HW_OFFLOAD */
73 	NF_FLOWTABLE_COUNTER		= 0x2,	/* NFT_FLOWTABLE_COUNTER */
74 };
75 
76 struct nf_flowtable {
77 	struct list_head		list;
78 	struct rhashtable		rhashtable;
79 	int				priority;
80 	const struct nf_flowtable_type	*type;
81 	struct delayed_work		gc_work;
82 	unsigned int			flags;
83 	struct flow_block		flow_block;
84 	struct rw_semaphore		flow_block_lock; /* Guards flow_block */
85 	possible_net_t			net;
86 };
87 
nf_flowtable_hw_offload(struct nf_flowtable * flowtable)88 static inline bool nf_flowtable_hw_offload(struct nf_flowtable *flowtable)
89 {
90 	return flowtable->flags & NF_FLOWTABLE_HW_OFFLOAD;
91 }
92 
93 enum flow_offload_tuple_dir {
94 	FLOW_OFFLOAD_DIR_ORIGINAL = IP_CT_DIR_ORIGINAL,
95 	FLOW_OFFLOAD_DIR_REPLY = IP_CT_DIR_REPLY,
96 };
97 #define FLOW_OFFLOAD_DIR_MAX	IP_CT_DIR_MAX
98 
99 enum flow_offload_xmit_type {
100 	FLOW_OFFLOAD_XMIT_UNSPEC	= 0,
101 	FLOW_OFFLOAD_XMIT_NEIGH,
102 	FLOW_OFFLOAD_XMIT_XFRM,
103 	FLOW_OFFLOAD_XMIT_DIRECT,
104 	FLOW_OFFLOAD_XMIT_TC,
105 };
106 
107 #define NF_FLOW_TABLE_ENCAP_MAX		2
108 
109 struct flow_offload_tuple {
110 	union {
111 		struct in_addr		src_v4;
112 		struct in6_addr		src_v6;
113 	};
114 	union {
115 		struct in_addr		dst_v4;
116 		struct in6_addr		dst_v6;
117 	};
118 	struct {
119 		__be16			src_port;
120 		__be16			dst_port;
121 	};
122 
123 	int				iifidx;
124 
125 	u8				l3proto;
126 	u8				l4proto;
127 	struct {
128 		u16			id;
129 		__be16			proto;
130 	} encap[NF_FLOW_TABLE_ENCAP_MAX];
131 
132 	/* All members above are keys for lookups, see flow_offload_hash(). */
133 	struct { }			__hash;
134 
135 	u8				dir:2,
136 					xmit_type:3,
137 					encap_num:2,
138 					in_vlan_ingress:2;
139 	u16				mtu;
140 	union {
141 		struct {
142 			struct dst_entry *dst_cache;
143 			u32		dst_cookie;
144 		};
145 		struct {
146 			u32		ifidx;
147 			u32		hw_ifidx;
148 			u8		h_source[ETH_ALEN];
149 			u8		h_dest[ETH_ALEN];
150 		} out;
151 		struct {
152 			u32		iifidx;
153 		} tc;
154 	};
155 };
156 
157 struct flow_offload_tuple_rhash {
158 	struct rhash_head		node;
159 	struct flow_offload_tuple	tuple;
160 };
161 
162 enum nf_flow_flags {
163 	NF_FLOW_SNAT,
164 	NF_FLOW_DNAT,
165 	NF_FLOW_TEARDOWN,
166 	NF_FLOW_HW,
167 	NF_FLOW_HW_DYING,
168 	NF_FLOW_HW_DEAD,
169 	NF_FLOW_HW_PENDING,
170 	NF_FLOW_HW_BIDIRECTIONAL,
171 	NF_FLOW_HW_ESTABLISHED,
172 };
173 
174 enum flow_offload_type {
175 	NF_FLOW_OFFLOAD_UNSPEC	= 0,
176 	NF_FLOW_OFFLOAD_ROUTE,
177 };
178 
179 struct flow_offload {
180 	struct flow_offload_tuple_rhash		tuplehash[FLOW_OFFLOAD_DIR_MAX];
181 	struct nf_conn				*ct;
182 	unsigned long				flags;
183 	u16					type;
184 	u32					timeout;
185 	struct rcu_head				rcu_head;
186 };
187 
188 #define NF_FLOW_TIMEOUT (30 * HZ)
189 #define nf_flowtable_time_stamp	(u32)jiffies
190 
191 unsigned long flow_offload_get_timeout(struct flow_offload *flow);
192 
nf_flow_timeout_delta(unsigned int timeout)193 static inline __s32 nf_flow_timeout_delta(unsigned int timeout)
194 {
195 	return (__s32)(timeout - nf_flowtable_time_stamp);
196 }
197 
198 struct nf_flow_route {
199 	struct {
200 		struct dst_entry		*dst;
201 		struct {
202 			u32			ifindex;
203 			struct {
204 				u16		id;
205 				__be16		proto;
206 			} encap[NF_FLOW_TABLE_ENCAP_MAX];
207 			u8			num_encaps:2,
208 						ingress_vlans:2;
209 		} in;
210 		struct {
211 			u32			ifindex;
212 			u32			hw_ifindex;
213 			u8			h_source[ETH_ALEN];
214 			u8			h_dest[ETH_ALEN];
215 		} out;
216 		enum flow_offload_xmit_type	xmit_type;
217 	} tuple[FLOW_OFFLOAD_DIR_MAX];
218 };
219 
220 struct flow_offload *flow_offload_alloc(struct nf_conn *ct);
221 void flow_offload_free(struct flow_offload *flow);
222 
223 static inline int
nf_flow_table_offload_add_cb(struct nf_flowtable * flow_table,flow_setup_cb_t * cb,void * cb_priv)224 nf_flow_table_offload_add_cb(struct nf_flowtable *flow_table,
225 			     flow_setup_cb_t *cb, void *cb_priv)
226 {
227 	struct flow_block *block = &flow_table->flow_block;
228 	struct flow_block_cb *block_cb;
229 	int err = 0;
230 
231 	down_write(&flow_table->flow_block_lock);
232 	block_cb = flow_block_cb_lookup(block, cb, cb_priv);
233 	if (block_cb) {
234 		err = -EEXIST;
235 		goto unlock;
236 	}
237 
238 	block_cb = flow_block_cb_alloc(cb, cb_priv, cb_priv, NULL);
239 	if (IS_ERR(block_cb)) {
240 		err = PTR_ERR(block_cb);
241 		goto unlock;
242 	}
243 
244 	list_add_tail(&block_cb->list, &block->cb_list);
245 	up_write(&flow_table->flow_block_lock);
246 
247 	if (flow_table->type->get)
248 		flow_table->type->get(flow_table);
249 	return 0;
250 
251 unlock:
252 	up_write(&flow_table->flow_block_lock);
253 	return err;
254 }
255 
256 static inline void
nf_flow_table_offload_del_cb(struct nf_flowtable * flow_table,flow_setup_cb_t * cb,void * cb_priv)257 nf_flow_table_offload_del_cb(struct nf_flowtable *flow_table,
258 			     flow_setup_cb_t *cb, void *cb_priv)
259 {
260 	struct flow_block *block = &flow_table->flow_block;
261 	struct flow_block_cb *block_cb;
262 
263 	down_write(&flow_table->flow_block_lock);
264 	block_cb = flow_block_cb_lookup(block, cb, cb_priv);
265 	if (block_cb) {
266 		list_del(&block_cb->list);
267 		flow_block_cb_free(block_cb);
268 	} else {
269 		WARN_ON(true);
270 	}
271 	up_write(&flow_table->flow_block_lock);
272 
273 	if (flow_table->type->put)
274 		flow_table->type->put(flow_table);
275 }
276 
277 void flow_offload_route_init(struct flow_offload *flow,
278 			     struct nf_flow_route *route);
279 
280 int flow_offload_add(struct nf_flowtable *flow_table, struct flow_offload *flow);
281 void flow_offload_refresh(struct nf_flowtable *flow_table,
282 			  struct flow_offload *flow, bool force);
283 
284 struct flow_offload_tuple_rhash *flow_offload_lookup(struct nf_flowtable *flow_table,
285 						     struct flow_offload_tuple *tuple);
286 void nf_flow_table_gc_run(struct nf_flowtable *flow_table);
287 void nf_flow_table_gc_cleanup(struct nf_flowtable *flowtable,
288 			      struct net_device *dev);
289 void nf_flow_table_cleanup(struct net_device *dev);
290 
291 int nf_flow_table_init(struct nf_flowtable *flow_table);
292 void nf_flow_table_free(struct nf_flowtable *flow_table);
293 
294 void flow_offload_teardown(struct flow_offload *flow);
295 
296 void nf_flow_snat_port(const struct flow_offload *flow,
297 		       struct sk_buff *skb, unsigned int thoff,
298 		       u8 protocol, enum flow_offload_tuple_dir dir);
299 void nf_flow_dnat_port(const struct flow_offload *flow,
300 		       struct sk_buff *skb, unsigned int thoff,
301 		       u8 protocol, enum flow_offload_tuple_dir dir);
302 
303 struct flow_ports {
304 	__be16 source, dest;
305 };
306 
307 unsigned int nf_flow_offload_ip_hook(void *priv, struct sk_buff *skb,
308 				     const struct nf_hook_state *state);
309 unsigned int nf_flow_offload_ipv6_hook(void *priv, struct sk_buff *skb,
310 				       const struct nf_hook_state *state);
311 
312 #define MODULE_ALIAS_NF_FLOWTABLE(family)	\
313 	MODULE_ALIAS("nf-flowtable-" __stringify(family))
314 
315 void nf_flow_offload_add(struct nf_flowtable *flowtable,
316 			 struct flow_offload *flow);
317 void nf_flow_offload_del(struct nf_flowtable *flowtable,
318 			 struct flow_offload *flow);
319 void nf_flow_offload_stats(struct nf_flowtable *flowtable,
320 			   struct flow_offload *flow);
321 
322 void nf_flow_table_offload_flush(struct nf_flowtable *flowtable);
323 void nf_flow_table_offload_flush_cleanup(struct nf_flowtable *flowtable);
324 
325 int nf_flow_table_offload_setup(struct nf_flowtable *flowtable,
326 				struct net_device *dev,
327 				enum flow_block_command cmd);
328 int nf_flow_rule_route_ipv4(struct net *net, struct flow_offload *flow,
329 			    enum flow_offload_tuple_dir dir,
330 			    struct nf_flow_rule *flow_rule);
331 int nf_flow_rule_route_ipv6(struct net *net, struct flow_offload *flow,
332 			    enum flow_offload_tuple_dir dir,
333 			    struct nf_flow_rule *flow_rule);
334 
335 int nf_flow_table_offload_init(void);
336 void nf_flow_table_offload_exit(void);
337 
nf_flow_pppoe_proto(const struct sk_buff * skb)338 static inline __be16 nf_flow_pppoe_proto(const struct sk_buff *skb)
339 {
340 	__be16 proto;
341 
342 	proto = *((__be16 *)(skb_mac_header(skb) + ETH_HLEN +
343 			     sizeof(struct pppoe_hdr)));
344 	switch (proto) {
345 	case htons(PPP_IP):
346 		return htons(ETH_P_IP);
347 	case htons(PPP_IPV6):
348 		return htons(ETH_P_IPV6);
349 	}
350 
351 	return 0;
352 }
353 
354 #define NF_FLOW_TABLE_STAT_INC(net, count) __this_cpu_inc((net)->ft.stat->count)
355 #define NF_FLOW_TABLE_STAT_DEC(net, count) __this_cpu_dec((net)->ft.stat->count)
356 #define NF_FLOW_TABLE_STAT_INC_ATOMIC(net, count)	\
357 	this_cpu_inc((net)->ft.stat->count)
358 #define NF_FLOW_TABLE_STAT_DEC_ATOMIC(net, count)	\
359 	this_cpu_dec((net)->ft.stat->count)
360 
361 #ifdef CONFIG_NF_FLOW_TABLE_PROCFS
362 int nf_flow_table_init_proc(struct net *net);
363 void nf_flow_table_fini_proc(struct net *net);
364 #else
nf_flow_table_init_proc(struct net * net)365 static inline int nf_flow_table_init_proc(struct net *net)
366 {
367 	return 0;
368 }
369 
nf_flow_table_fini_proc(struct net * net)370 static inline void nf_flow_table_fini_proc(struct net *net)
371 {
372 }
373 #endif /* CONFIG_NF_FLOW_TABLE_PROCFS */
374 
375 #endif /* _NF_FLOW_TABLE_H */
376