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