nf_flow_table.h

  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
 16struct nf_flowtable;
 17struct nf_flow_rule;
 18struct flow_offload;
 19enum flow_offload_tuple_dir;
 20
 21struct 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
 41struct nf_flow_match {
 42	struct flow_dissector	dissector;
 43	struct nf_flow_key	key;
 44	struct nf_flow_key	mask;
 45};
 46
 47struct nf_flow_rule {
 48	struct nf_flow_match	match;
 49	struct flow_rule	*rule;
 50};
 51
 52struct 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
 71enum nf_flowtable_flags {
 72	NF_FLOWTABLE_HW_OFFLOAD		= 0x1,	/* NFT_FLOWTABLE_HW_OFFLOAD */
 73	NF_FLOWTABLE_COUNTER		= 0x2,	/* NFT_FLOWTABLE_COUNTER */
 74};
 75
 76struct nf_flowtable {
 77	unsigned int			flags;		/* readonly in datapath */
 78	int				priority;	/* control path (padding hole) */
 79	struct rhashtable		rhashtable;	/* datapath, read-mostly members come first */
 80
 81	struct list_head		list;		/* slowpath parts */
 82	const struct nf_flowtable_type	*type;
 83	struct delayed_work		gc_work;
 84	struct flow_block		flow_block;
 85	struct rw_semaphore		flow_block_lock; /* Guards flow_block */
 86	possible_net_t			net;
 87};
 88
 89static inline bool nf_flowtable_hw_offload(struct nf_flowtable *flowtable)
 90{
 91	return flowtable->flags & NF_FLOWTABLE_HW_OFFLOAD;
 92}
 93
 94enum flow_offload_tuple_dir {
 95	FLOW_OFFLOAD_DIR_ORIGINAL = IP_CT_DIR_ORIGINAL,
 96	FLOW_OFFLOAD_DIR_REPLY = IP_CT_DIR_REPLY,
 97};
 98#define FLOW_OFFLOAD_DIR_MAX	IP_CT_DIR_MAX
 99
100enum flow_offload_xmit_type {
101	FLOW_OFFLOAD_XMIT_UNSPEC	= 0,
102	FLOW_OFFLOAD_XMIT_NEIGH,
103	FLOW_OFFLOAD_XMIT_XFRM,
104	FLOW_OFFLOAD_XMIT_DIRECT,
105	FLOW_OFFLOAD_XMIT_TC,
106};
107
108#define NF_FLOW_TABLE_ENCAP_MAX		2
109
110struct flow_offload_tunnel {
111	union {
112		struct in_addr	src_v4;
113		struct in6_addr	src_v6;
114	};
115	union {
116		struct in_addr	dst_v4;
117		struct in6_addr	dst_v6;
118	};
119
120	u8	l3_proto;
121};
122
123struct flow_offload_tuple {
124	union {
125		struct in_addr		src_v4;
126		struct in6_addr		src_v6;
127	};
128	union {
129		struct in_addr		dst_v4;
130		struct in6_addr		dst_v6;
131	};
132	struct {
133		__be16			src_port;
134		__be16			dst_port;
135	};
136
137	int				iifidx;
138
139	u8				l3proto;
140	u8				l4proto;
141	struct {
142		u16			id;
143		__be16			proto;
144	} encap[NF_FLOW_TABLE_ENCAP_MAX];
145
146	struct flow_offload_tunnel	tun;
147
148	/* All members above are keys for lookups, see flow_offload_hash(). */
149	struct { }			__hash;
150
151	u8				dir:2,
152					xmit_type:3,
153					encap_num:2,
154					tun_num:2,
155					in_vlan_ingress:2;
156	u16				mtu;
157	union {
158		struct {
159			struct dst_entry *dst_cache;
160			u32		ifidx;
161			u32		dst_cookie;
162		};
163		struct {
164			u32		ifidx;
165			u8		h_source[ETH_ALEN];
166			u8		h_dest[ETH_ALEN];
167		} out;
168		struct {
169			u32		iifidx;
170		} tc;
171	};
172};
173
174struct flow_offload_tuple_rhash {
175	struct rhash_head		node;
176	struct flow_offload_tuple	tuple;
177};
178
179enum nf_flow_flags {
180	NF_FLOW_SNAT,
181	NF_FLOW_DNAT,
182	NF_FLOW_CLOSING,
183	NF_FLOW_TEARDOWN,
184	NF_FLOW_HW,
185	NF_FLOW_HW_DYING,
186	NF_FLOW_HW_DEAD,
187	NF_FLOW_HW_PENDING,
188	NF_FLOW_HW_BIDIRECTIONAL,
189	NF_FLOW_HW_ESTABLISHED,
190};
191
192enum flow_offload_type {
193	NF_FLOW_OFFLOAD_UNSPEC	= 0,
194	NF_FLOW_OFFLOAD_ROUTE,
195};
196
197struct flow_offload {
198	struct flow_offload_tuple_rhash		tuplehash[FLOW_OFFLOAD_DIR_MAX];
199	struct nf_conn				*ct;
200	unsigned long				flags;
201	u16					type;
202	u32					timeout;
203	struct rcu_head				rcu_head;
204};
205
206#define NF_FLOW_TIMEOUT (30 * HZ)
207#define nf_flowtable_time_stamp	(u32)jiffies
208
209unsigned long flow_offload_get_timeout(struct flow_offload *flow);
210
211static inline __s32 nf_flow_timeout_delta(unsigned int timeout)
212{
213	return (__s32)(timeout - nf_flowtable_time_stamp);
214}
215
216struct nf_flow_route {
217	struct {
218		struct dst_entry		*dst;
219		struct {
220			u32			ifindex;
221			struct {
222				u16		id;
223				__be16		proto;
224			} encap[NF_FLOW_TABLE_ENCAP_MAX];
225			struct flow_offload_tunnel tun;
226			u8			num_encaps:2,
227						num_tuns:2,
228						ingress_vlans:2;
229		} in;
230		struct {
231			u32			ifindex;
232			u32			hw_ifindex;
233			u8			h_source[ETH_ALEN];
234			u8			h_dest[ETH_ALEN];
235		} out;
236		enum flow_offload_xmit_type	xmit_type;
237	} tuple[FLOW_OFFLOAD_DIR_MAX];
238};
239
240struct flow_offload *flow_offload_alloc(struct nf_conn *ct);
241void flow_offload_free(struct flow_offload *flow);
242
243struct nft_flowtable;
244struct nft_pktinfo;
245int nft_flow_route(const struct nft_pktinfo *pkt, const struct nf_conn *ct,
246		   struct nf_flow_route *route, enum ip_conntrack_dir dir,
247		   struct nft_flowtable *ft);
248
249static inline int
250nf_flow_table_offload_add_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	int err = 0;
256
257	down_write(&flow_table->flow_block_lock);
258	block_cb = flow_block_cb_lookup(block, cb, cb_priv);
259	if (block_cb) {
260		err = -EEXIST;
261		goto unlock;
262	}
263
264	block_cb = flow_block_cb_alloc(cb, cb_priv, cb_priv, NULL);
265	if (IS_ERR(block_cb)) {
266		err = PTR_ERR(block_cb);
267		goto unlock;
268	}
269
270	list_add_tail(&block_cb->list, &block->cb_list);
271	up_write(&flow_table->flow_block_lock);
272
273	if (flow_table->type->get)
274		flow_table->type->get(flow_table);
275	return 0;
276
277unlock:
278	up_write(&flow_table->flow_block_lock);
279	return err;
280}
281
282static inline void
283nf_flow_table_offload_del_cb(struct nf_flowtable *flow_table,
284			     flow_setup_cb_t *cb, void *cb_priv)
285{
286	struct flow_block *block = &flow_table->flow_block;
287	struct flow_block_cb *block_cb;
288
289	down_write(&flow_table->flow_block_lock);
290	block_cb = flow_block_cb_lookup(block, cb, cb_priv);
291	if (block_cb) {
292		list_del(&block_cb->list);
293		flow_block_cb_free(block_cb);
294	} else {
295		WARN_ON(true);
296	}
297	up_write(&flow_table->flow_block_lock);
298
299	if (flow_table->type->put)
300		flow_table->type->put(flow_table);
301}
302
303void flow_offload_route_init(struct flow_offload *flow,
304			     struct nf_flow_route *route);
305
306int flow_offload_add(struct nf_flowtable *flow_table, struct flow_offload *flow);
307void flow_offload_refresh(struct nf_flowtable *flow_table,
308			  struct flow_offload *flow, bool force);
309
310struct flow_offload_tuple_rhash *flow_offload_lookup(struct nf_flowtable *flow_table,
311						     struct flow_offload_tuple *tuple);
312void nf_flow_table_gc_run(struct nf_flowtable *flow_table);
313void nf_flow_table_gc_cleanup(struct nf_flowtable *flowtable,
314			      struct net_device *dev);
315void nf_flow_table_cleanup(struct net_device *dev);
316
317int nf_flow_table_init(struct nf_flowtable *flow_table);
318void nf_flow_table_free(struct nf_flowtable *flow_table);
319
320void flow_offload_teardown(struct flow_offload *flow);
321
322void nf_flow_snat_port(const struct flow_offload *flow,
323		       struct sk_buff *skb, unsigned int thoff,
324		       u8 protocol, enum flow_offload_tuple_dir dir);
325void nf_flow_dnat_port(const struct flow_offload *flow,
326		       struct sk_buff *skb, unsigned int thoff,
327		       u8 protocol, enum flow_offload_tuple_dir dir);
328
329struct flow_ports {
330	__be16 source, dest;
331};
332
333struct nf_flowtable *nf_flowtable_by_dev(const struct net_device *dev);
334int nf_flow_offload_xdp_setup(struct nf_flowtable *flowtable,
335			      struct net_device *dev,
336			      enum flow_block_command cmd);
337
338unsigned int nf_flow_offload_ip_hook(void *priv, struct sk_buff *skb,
339				     const struct nf_hook_state *state);
340unsigned int nf_flow_offload_ipv6_hook(void *priv, struct sk_buff *skb,
341				       const struct nf_hook_state *state);
342
343#if (IS_BUILTIN(CONFIG_NF_FLOW_TABLE) && IS_ENABLED(CONFIG_DEBUG_INFO_BTF)) || \
344    (IS_MODULE(CONFIG_NF_FLOW_TABLE) && IS_ENABLED(CONFIG_DEBUG_INFO_BTF_MODULES))
345extern int nf_flow_register_bpf(void);
346#else
347static inline int nf_flow_register_bpf(void)
348{
349	return 0;
350}
351#endif
352
353#define MODULE_ALIAS_NF_FLOWTABLE(family)	\
354	MODULE_ALIAS("nf-flowtable-" __stringify(family))
355
356void nf_flow_offload_add(struct nf_flowtable *flowtable,
357			 struct flow_offload *flow);
358void nf_flow_offload_del(struct nf_flowtable *flowtable,
359			 struct flow_offload *flow);
360void nf_flow_offload_stats(struct nf_flowtable *flowtable,
361			   struct flow_offload *flow);
362
363void nf_flow_table_offload_flush(struct nf_flowtable *flowtable);
364void nf_flow_table_offload_flush_cleanup(struct nf_flowtable *flowtable);
365
366int nf_flow_table_offload_setup(struct nf_flowtable *flowtable,
367				struct net_device *dev,
368				enum flow_block_command cmd);
369int nf_flow_rule_route_ipv4(struct net *net, struct flow_offload *flow,
370			    enum flow_offload_tuple_dir dir,
371			    struct nf_flow_rule *flow_rule);
372int nf_flow_rule_route_ipv6(struct net *net, struct flow_offload *flow,
373			    enum flow_offload_tuple_dir dir,
374			    struct nf_flow_rule *flow_rule);
375
376int nf_flow_table_offload_init(void);
377void nf_flow_table_offload_exit(void);
378
379static inline __be16 __nf_flow_pppoe_proto(const struct sk_buff *skb)
380{
381	__be16 proto;
382
383	proto = *((__be16 *)(skb_mac_header(skb) + ETH_HLEN +
384			     sizeof(struct pppoe_hdr)));
385	switch (proto) {
386	case htons(PPP_IP):
387		return htons(ETH_P_IP);
388	case htons(PPP_IPV6):
389		return htons(ETH_P_IPV6);
390	}
391
392	return 0;
393}
394
395static inline bool nf_flow_pppoe_proto(struct sk_buff *skb, __be16 *inner_proto)
396{
397	if (!pskb_may_pull(skb, ETH_HLEN + PPPOE_SES_HLEN))
398		return false;
399
400	*inner_proto = __nf_flow_pppoe_proto(skb);
401
402	return true;
403}
404
405#define NF_FLOW_TABLE_STAT_INC(net, count) __this_cpu_inc((net)->ft.stat->count)
406#define NF_FLOW_TABLE_STAT_DEC(net, count) __this_cpu_dec((net)->ft.stat->count)
407#define NF_FLOW_TABLE_STAT_INC_ATOMIC(net, count)	\
408	this_cpu_inc((net)->ft.stat->count)
409#define NF_FLOW_TABLE_STAT_DEC_ATOMIC(net, count)	\
410	this_cpu_dec((net)->ft.stat->count)
411
412#ifdef CONFIG_NF_FLOW_TABLE_PROCFS
413int nf_flow_table_init_proc(struct net *net);
414void nf_flow_table_fini_proc(struct net *net);
415#else
416static inline int nf_flow_table_init_proc(struct net *net)
417{
418	return 0;
419}
420
421static inline void nf_flow_table_fini_proc(struct net *net)
422{
423}
424#endif /* CONFIG_NF_FLOW_TABLE_PROCFS */
425
426#endif /* _NF_FLOW_TABLE_H */