xref: /openbmc/linux/include/net/ip_vs.h (revision 9344dade)
1 /*
2  *      IP Virtual Server
3  *      data structure and functionality definitions
4  */
5 
6 #ifndef _NET_IP_VS_H
7 #define _NET_IP_VS_H
8 
9 #include <linux/ip_vs.h>                /* definitions shared with userland */
10 
11 #include <asm/types.h>                  /* for __uXX types */
12 
13 #include <linux/list.h>                 /* for struct list_head */
14 #include <linux/spinlock.h>             /* for struct rwlock_t */
15 #include <linux/atomic.h>                 /* for struct atomic_t */
16 #include <linux/compiler.h>
17 #include <linux/timer.h>
18 #include <linux/bug.h>
19 
20 #include <net/checksum.h>
21 #include <linux/netfilter.h>		/* for union nf_inet_addr */
22 #include <linux/ip.h>
23 #include <linux/ipv6.h>			/* for struct ipv6hdr */
24 #include <net/ipv6.h>
25 #if IS_ENABLED(CONFIG_IP_VS_IPV6)
26 #include <linux/netfilter_ipv6/ip6_tables.h>
27 #endif
28 #if IS_ENABLED(CONFIG_NF_CONNTRACK)
29 #include <net/netfilter/nf_conntrack.h>
30 #endif
31 #include <net/net_namespace.h>		/* Netw namespace */
32 
33 /*
34  * Generic access of ipvs struct
35  */
36 static inline struct netns_ipvs *net_ipvs(struct net* net)
37 {
38 	return net->ipvs;
39 }
40 /*
41  * Get net ptr from skb in traffic cases
42  * use skb_sknet when call is from userland (ioctl or netlink)
43  */
44 static inline struct net *skb_net(const struct sk_buff *skb)
45 {
46 #ifdef CONFIG_NET_NS
47 #ifdef CONFIG_IP_VS_DEBUG
48 	/*
49 	 * This is used for debug only.
50 	 * Start with the most likely hit
51 	 * End with BUG
52 	 */
53 	if (likely(skb->dev && skb->dev->nd_net))
54 		return dev_net(skb->dev);
55 	if (skb_dst(skb) && skb_dst(skb)->dev)
56 		return dev_net(skb_dst(skb)->dev);
57 	WARN(skb->sk, "Maybe skb_sknet should be used in %s() at line:%d\n",
58 		      __func__, __LINE__);
59 	if (likely(skb->sk && skb->sk->sk_net))
60 		return sock_net(skb->sk);
61 	pr_err("There is no net ptr to find in the skb in %s() line:%d\n",
62 		__func__, __LINE__);
63 	BUG();
64 #else
65 	return dev_net(skb->dev ? : skb_dst(skb)->dev);
66 #endif
67 #else
68 	return &init_net;
69 #endif
70 }
71 
72 static inline struct net *skb_sknet(const struct sk_buff *skb)
73 {
74 #ifdef CONFIG_NET_NS
75 #ifdef CONFIG_IP_VS_DEBUG
76 	/* Start with the most likely hit */
77 	if (likely(skb->sk && skb->sk->sk_net))
78 		return sock_net(skb->sk);
79 	WARN(skb->dev, "Maybe skb_net should be used instead in %s() line:%d\n",
80 		       __func__, __LINE__);
81 	if (likely(skb->dev && skb->dev->nd_net))
82 		return dev_net(skb->dev);
83 	pr_err("There is no net ptr to find in the skb in %s() line:%d\n",
84 		__func__, __LINE__);
85 	BUG();
86 #else
87 	return sock_net(skb->sk);
88 #endif
89 #else
90 	return &init_net;
91 #endif
92 }
93 /*
94  * This one needed for single_open_net since net is stored directly in
95  * private not as a struct i.e. seq_file_net can't be used.
96  */
97 static inline struct net *seq_file_single_net(struct seq_file *seq)
98 {
99 #ifdef CONFIG_NET_NS
100 	return (struct net *)seq->private;
101 #else
102 	return &init_net;
103 #endif
104 }
105 
106 /* Connections' size value needed by ip_vs_ctl.c */
107 extern int ip_vs_conn_tab_size;
108 
109 struct ip_vs_iphdr {
110 	__u32 len;	/* IPv4 simply where L4 starts
111 			   IPv6 where L4 Transport Header starts */
112 	__u32 thoff_reasm; /* Transport Header Offset in nfct_reasm skb */
113 	__u16 fragoffs; /* IPv6 fragment offset, 0 if first frag (or not frag)*/
114 	__s16 protocol;
115 	__s32 flags;
116 	union nf_inet_addr saddr;
117 	union nf_inet_addr daddr;
118 };
119 
120 /* Dependency to module: nf_defrag_ipv6 */
121 #if defined(CONFIG_NF_DEFRAG_IPV6) || defined(CONFIG_NF_DEFRAG_IPV6_MODULE)
122 static inline struct sk_buff *skb_nfct_reasm(const struct sk_buff *skb)
123 {
124 	return skb->nfct_reasm;
125 }
126 static inline void *frag_safe_skb_hp(const struct sk_buff *skb, int offset,
127 				      int len, void *buffer,
128 				      const struct ip_vs_iphdr *ipvsh)
129 {
130 	if (unlikely(ipvsh->fragoffs && skb_nfct_reasm(skb)))
131 		return skb_header_pointer(skb_nfct_reasm(skb),
132 					  ipvsh->thoff_reasm, len, buffer);
133 
134 	return skb_header_pointer(skb, offset, len, buffer);
135 }
136 #else
137 static inline struct sk_buff *skb_nfct_reasm(const struct sk_buff *skb)
138 {
139 	return NULL;
140 }
141 static inline void *frag_safe_skb_hp(const struct sk_buff *skb, int offset,
142 				      int len, void *buffer,
143 				      const struct ip_vs_iphdr *ipvsh)
144 {
145 	return skb_header_pointer(skb, offset, len, buffer);
146 }
147 #endif
148 
149 static inline void
150 ip_vs_fill_ip4hdr(const void *nh, struct ip_vs_iphdr *iphdr)
151 {
152 	const struct iphdr *iph = nh;
153 
154 	iphdr->len	= iph->ihl * 4;
155 	iphdr->fragoffs	= 0;
156 	iphdr->protocol	= iph->protocol;
157 	iphdr->saddr.ip	= iph->saddr;
158 	iphdr->daddr.ip	= iph->daddr;
159 }
160 
161 /* This function handles filling *ip_vs_iphdr, both for IPv4 and IPv6.
162  * IPv6 requires some extra work, as finding proper header position,
163  * depend on the IPv6 extension headers.
164  */
165 static inline void
166 ip_vs_fill_iph_skb(int af, const struct sk_buff *skb, struct ip_vs_iphdr *iphdr)
167 {
168 #ifdef CONFIG_IP_VS_IPV6
169 	if (af == AF_INET6) {
170 		const struct ipv6hdr *iph =
171 			(struct ipv6hdr *)skb_network_header(skb);
172 		iphdr->saddr.in6 = iph->saddr;
173 		iphdr->daddr.in6 = iph->daddr;
174 		/* ipv6_find_hdr() updates len, flags, thoff_reasm */
175 		iphdr->thoff_reasm = 0;
176 		iphdr->len	 = 0;
177 		iphdr->flags	 = 0;
178 		iphdr->protocol  = ipv6_find_hdr(skb, &iphdr->len, -1,
179 						 &iphdr->fragoffs,
180 						 &iphdr->flags);
181 		/* get proto from re-assembled packet and it's offset */
182 		if (skb_nfct_reasm(skb))
183 			iphdr->protocol = ipv6_find_hdr(skb_nfct_reasm(skb),
184 							&iphdr->thoff_reasm,
185 							-1, NULL, NULL);
186 
187 	} else
188 #endif
189 	{
190 		const struct iphdr *iph =
191 			(struct iphdr *)skb_network_header(skb);
192 		iphdr->len	= iph->ihl * 4;
193 		iphdr->fragoffs	= 0;
194 		iphdr->protocol	= iph->protocol;
195 		iphdr->saddr.ip	= iph->saddr;
196 		iphdr->daddr.ip	= iph->daddr;
197 	}
198 }
199 
200 static inline void ip_vs_addr_copy(int af, union nf_inet_addr *dst,
201 				   const union nf_inet_addr *src)
202 {
203 #ifdef CONFIG_IP_VS_IPV6
204 	if (af == AF_INET6)
205 		dst->in6 = src->in6;
206 	else
207 #endif
208 	dst->ip = src->ip;
209 }
210 
211 static inline void ip_vs_addr_set(int af, union nf_inet_addr *dst,
212 				  const union nf_inet_addr *src)
213 {
214 #ifdef CONFIG_IP_VS_IPV6
215 	if (af == AF_INET6) {
216 		dst->in6 = src->in6;
217 		return;
218 	}
219 #endif
220 	dst->ip = src->ip;
221 	dst->all[1] = 0;
222 	dst->all[2] = 0;
223 	dst->all[3] = 0;
224 }
225 
226 static inline int ip_vs_addr_equal(int af, const union nf_inet_addr *a,
227 				   const union nf_inet_addr *b)
228 {
229 #ifdef CONFIG_IP_VS_IPV6
230 	if (af == AF_INET6)
231 		return ipv6_addr_equal(&a->in6, &b->in6);
232 #endif
233 	return a->ip == b->ip;
234 }
235 
236 #ifdef CONFIG_IP_VS_DEBUG
237 #include <linux/net.h>
238 
239 extern int ip_vs_get_debug_level(void);
240 
241 static inline const char *ip_vs_dbg_addr(int af, char *buf, size_t buf_len,
242 					 const union nf_inet_addr *addr,
243 					 int *idx)
244 {
245 	int len;
246 #ifdef CONFIG_IP_VS_IPV6
247 	if (af == AF_INET6)
248 		len = snprintf(&buf[*idx], buf_len - *idx, "[%pI6c]",
249 			       &addr->in6) + 1;
250 	else
251 #endif
252 		len = snprintf(&buf[*idx], buf_len - *idx, "%pI4",
253 			       &addr->ip) + 1;
254 
255 	*idx += len;
256 	BUG_ON(*idx > buf_len + 1);
257 	return &buf[*idx - len];
258 }
259 
260 #define IP_VS_DBG_BUF(level, msg, ...)					\
261 	do {								\
262 		char ip_vs_dbg_buf[160];				\
263 		int ip_vs_dbg_idx = 0;					\
264 		if (level <= ip_vs_get_debug_level())			\
265 			printk(KERN_DEBUG pr_fmt(msg), ##__VA_ARGS__);	\
266 	} while (0)
267 #define IP_VS_ERR_BUF(msg...)						\
268 	do {								\
269 		char ip_vs_dbg_buf[160];				\
270 		int ip_vs_dbg_idx = 0;					\
271 		pr_err(msg);						\
272 	} while (0)
273 
274 /* Only use from within IP_VS_DBG_BUF() or IP_VS_ERR_BUF macros */
275 #define IP_VS_DBG_ADDR(af, addr)					\
276 	ip_vs_dbg_addr(af, ip_vs_dbg_buf,				\
277 		       sizeof(ip_vs_dbg_buf), addr,			\
278 		       &ip_vs_dbg_idx)
279 
280 #define IP_VS_DBG(level, msg, ...)					\
281 	do {								\
282 		if (level <= ip_vs_get_debug_level())			\
283 			printk(KERN_DEBUG pr_fmt(msg), ##__VA_ARGS__);	\
284 	} while (0)
285 #define IP_VS_DBG_RL(msg, ...)						\
286 	do {								\
287 		if (net_ratelimit())					\
288 			printk(KERN_DEBUG pr_fmt(msg), ##__VA_ARGS__);	\
289 	} while (0)
290 #define IP_VS_DBG_PKT(level, af, pp, skb, ofs, msg)			\
291 	do {								\
292 		if (level <= ip_vs_get_debug_level())			\
293 			pp->debug_packet(af, pp, skb, ofs, msg);	\
294 	} while (0)
295 #define IP_VS_DBG_RL_PKT(level, af, pp, skb, ofs, msg)			\
296 	do {								\
297 		if (level <= ip_vs_get_debug_level() &&			\
298 		    net_ratelimit())					\
299 			pp->debug_packet(af, pp, skb, ofs, msg);	\
300 	} while (0)
301 #else	/* NO DEBUGGING at ALL */
302 #define IP_VS_DBG_BUF(level, msg...)  do {} while (0)
303 #define IP_VS_ERR_BUF(msg...)  do {} while (0)
304 #define IP_VS_DBG(level, msg...)  do {} while (0)
305 #define IP_VS_DBG_RL(msg...)  do {} while (0)
306 #define IP_VS_DBG_PKT(level, af, pp, skb, ofs, msg)	do {} while (0)
307 #define IP_VS_DBG_RL_PKT(level, af, pp, skb, ofs, msg)	do {} while (0)
308 #endif
309 
310 #define IP_VS_BUG() BUG()
311 #define IP_VS_ERR_RL(msg, ...)						\
312 	do {								\
313 		if (net_ratelimit())					\
314 			pr_err(msg, ##__VA_ARGS__);			\
315 	} while (0)
316 
317 #ifdef CONFIG_IP_VS_DEBUG
318 #define EnterFunction(level)						\
319 	do {								\
320 		if (level <= ip_vs_get_debug_level())			\
321 			printk(KERN_DEBUG				\
322 			       pr_fmt("Enter: %s, %s line %i\n"),	\
323 			       __func__, __FILE__, __LINE__);		\
324 	} while (0)
325 #define LeaveFunction(level)						\
326 	do {								\
327 		if (level <= ip_vs_get_debug_level())			\
328 			printk(KERN_DEBUG				\
329 			       pr_fmt("Leave: %s, %s line %i\n"),	\
330 			       __func__, __FILE__, __LINE__);		\
331 	} while (0)
332 #else
333 #define EnterFunction(level)   do {} while (0)
334 #define LeaveFunction(level)   do {} while (0)
335 #endif
336 
337 
338 /*
339  *      The port number of FTP service (in network order).
340  */
341 #define FTPPORT  cpu_to_be16(21)
342 #define FTPDATA  cpu_to_be16(20)
343 
344 /*
345  *      TCP State Values
346  */
347 enum {
348 	IP_VS_TCP_S_NONE = 0,
349 	IP_VS_TCP_S_ESTABLISHED,
350 	IP_VS_TCP_S_SYN_SENT,
351 	IP_VS_TCP_S_SYN_RECV,
352 	IP_VS_TCP_S_FIN_WAIT,
353 	IP_VS_TCP_S_TIME_WAIT,
354 	IP_VS_TCP_S_CLOSE,
355 	IP_VS_TCP_S_CLOSE_WAIT,
356 	IP_VS_TCP_S_LAST_ACK,
357 	IP_VS_TCP_S_LISTEN,
358 	IP_VS_TCP_S_SYNACK,
359 	IP_VS_TCP_S_LAST
360 };
361 
362 /*
363  *	UDP State Values
364  */
365 enum {
366 	IP_VS_UDP_S_NORMAL,
367 	IP_VS_UDP_S_LAST,
368 };
369 
370 /*
371  *	ICMP State Values
372  */
373 enum {
374 	IP_VS_ICMP_S_NORMAL,
375 	IP_VS_ICMP_S_LAST,
376 };
377 
378 /*
379  *	SCTP State Values
380  */
381 enum ip_vs_sctp_states {
382 	IP_VS_SCTP_S_NONE,
383 	IP_VS_SCTP_S_INIT1,
384 	IP_VS_SCTP_S_INIT,
385 	IP_VS_SCTP_S_COOKIE_SENT,
386 	IP_VS_SCTP_S_COOKIE_REPLIED,
387 	IP_VS_SCTP_S_COOKIE_WAIT,
388 	IP_VS_SCTP_S_COOKIE,
389 	IP_VS_SCTP_S_COOKIE_ECHOED,
390 	IP_VS_SCTP_S_ESTABLISHED,
391 	IP_VS_SCTP_S_SHUTDOWN_SENT,
392 	IP_VS_SCTP_S_SHUTDOWN_RECEIVED,
393 	IP_VS_SCTP_S_SHUTDOWN_ACK_SENT,
394 	IP_VS_SCTP_S_REJECTED,
395 	IP_VS_SCTP_S_CLOSED,
396 	IP_VS_SCTP_S_LAST
397 };
398 
399 /*
400  *	Delta sequence info structure
401  *	Each ip_vs_conn has 2 (output AND input seq. changes).
402  *      Only used in the VS/NAT.
403  */
404 struct ip_vs_seq {
405 	__u32			init_seq;	/* Add delta from this seq */
406 	__u32			delta;		/* Delta in sequence numbers */
407 	__u32			previous_delta;	/* Delta in sequence numbers
408 						   before last resized pkt */
409 };
410 
411 /*
412  * counters per cpu
413  */
414 struct ip_vs_counters {
415 	__u32		conns;		/* connections scheduled */
416 	__u32		inpkts;		/* incoming packets */
417 	__u32		outpkts;	/* outgoing packets */
418 	__u64		inbytes;	/* incoming bytes */
419 	__u64		outbytes;	/* outgoing bytes */
420 };
421 /*
422  * Stats per cpu
423  */
424 struct ip_vs_cpu_stats {
425 	struct ip_vs_counters   ustats;
426 	struct u64_stats_sync   syncp;
427 };
428 
429 /*
430  *	IPVS statistics objects
431  */
432 struct ip_vs_estimator {
433 	struct list_head	list;
434 
435 	u64			last_inbytes;
436 	u64			last_outbytes;
437 	u32			last_conns;
438 	u32			last_inpkts;
439 	u32			last_outpkts;
440 
441 	u32			cps;
442 	u32			inpps;
443 	u32			outpps;
444 	u32			inbps;
445 	u32			outbps;
446 };
447 
448 struct ip_vs_stats {
449 	struct ip_vs_stats_user	ustats;		/* statistics */
450 	struct ip_vs_estimator	est;		/* estimator */
451 	struct ip_vs_cpu_stats __percpu	*cpustats;	/* per cpu counters */
452 	spinlock_t		lock;		/* spin lock */
453 	struct ip_vs_stats_user	ustats0;	/* reset values */
454 };
455 
456 struct dst_entry;
457 struct iphdr;
458 struct ip_vs_conn;
459 struct ip_vs_app;
460 struct sk_buff;
461 struct ip_vs_proto_data;
462 
463 struct ip_vs_protocol {
464 	struct ip_vs_protocol	*next;
465 	char			*name;
466 	u16			protocol;
467 	u16			num_states;
468 	int			dont_defrag;
469 
470 	void (*init)(struct ip_vs_protocol *pp);
471 
472 	void (*exit)(struct ip_vs_protocol *pp);
473 
474 	int (*init_netns)(struct net *net, struct ip_vs_proto_data *pd);
475 
476 	void (*exit_netns)(struct net *net, struct ip_vs_proto_data *pd);
477 
478 	int (*conn_schedule)(int af, struct sk_buff *skb,
479 			     struct ip_vs_proto_data *pd,
480 			     int *verdict, struct ip_vs_conn **cpp,
481 			     struct ip_vs_iphdr *iph);
482 
483 	struct ip_vs_conn *
484 	(*conn_in_get)(int af,
485 		       const struct sk_buff *skb,
486 		       const struct ip_vs_iphdr *iph,
487 		       int inverse);
488 
489 	struct ip_vs_conn *
490 	(*conn_out_get)(int af,
491 			const struct sk_buff *skb,
492 			const struct ip_vs_iphdr *iph,
493 			int inverse);
494 
495 	int (*snat_handler)(struct sk_buff *skb, struct ip_vs_protocol *pp,
496 			    struct ip_vs_conn *cp, struct ip_vs_iphdr *iph);
497 
498 	int (*dnat_handler)(struct sk_buff *skb, struct ip_vs_protocol *pp,
499 			    struct ip_vs_conn *cp, struct ip_vs_iphdr *iph);
500 
501 	int (*csum_check)(int af, struct sk_buff *skb,
502 			  struct ip_vs_protocol *pp);
503 
504 	const char *(*state_name)(int state);
505 
506 	void (*state_transition)(struct ip_vs_conn *cp, int direction,
507 				 const struct sk_buff *skb,
508 				 struct ip_vs_proto_data *pd);
509 
510 	int (*register_app)(struct net *net, struct ip_vs_app *inc);
511 
512 	void (*unregister_app)(struct net *net, struct ip_vs_app *inc);
513 
514 	int (*app_conn_bind)(struct ip_vs_conn *cp);
515 
516 	void (*debug_packet)(int af, struct ip_vs_protocol *pp,
517 			     const struct sk_buff *skb,
518 			     int offset,
519 			     const char *msg);
520 
521 	void (*timeout_change)(struct ip_vs_proto_data *pd, int flags);
522 };
523 
524 /*
525  * protocol data per netns
526  */
527 struct ip_vs_proto_data {
528 	struct ip_vs_proto_data	*next;
529 	struct ip_vs_protocol	*pp;
530 	int			*timeout_table;	/* protocol timeout table */
531 	atomic_t		appcnt;		/* counter of proto app incs. */
532 	struct tcp_states_t	*tcp_state_table;
533 };
534 
535 extern struct ip_vs_protocol   *ip_vs_proto_get(unsigned short proto);
536 extern struct ip_vs_proto_data *ip_vs_proto_data_get(struct net *net,
537 						     unsigned short proto);
538 
539 struct ip_vs_conn_param {
540 	struct net			*net;
541 	const union nf_inet_addr	*caddr;
542 	const union nf_inet_addr	*vaddr;
543 	__be16				cport;
544 	__be16				vport;
545 	__u16				protocol;
546 	u16				af;
547 
548 	const struct ip_vs_pe		*pe;
549 	char				*pe_data;
550 	__u8				pe_data_len;
551 };
552 
553 /*
554  *	IP_VS structure allocated for each dynamically scheduled connection
555  */
556 struct ip_vs_conn {
557 	struct hlist_node	c_list;         /* hashed list heads */
558 	/* Protocol, addresses and port numbers */
559 	__be16                  cport;
560 	__be16                  dport;
561 	__be16                  vport;
562 	u16			af;		/* address family */
563 	union nf_inet_addr      caddr;          /* client address */
564 	union nf_inet_addr      vaddr;          /* virtual address */
565 	union nf_inet_addr      daddr;          /* destination address */
566 	volatile __u32          flags;          /* status flags */
567 	__u16                   protocol;       /* Which protocol (TCP/UDP) */
568 #ifdef CONFIG_NET_NS
569 	struct net              *net;           /* Name space */
570 #endif
571 
572 	/* counter and timer */
573 	atomic_t		refcnt;		/* reference count */
574 	struct timer_list	timer;		/* Expiration timer */
575 	volatile unsigned long	timeout;	/* timeout */
576 
577 	/* Flags and state transition */
578 	spinlock_t              lock;           /* lock for state transition */
579 	volatile __u16          state;          /* state info */
580 	volatile __u16          old_state;      /* old state, to be used for
581 						 * state transition triggerd
582 						 * synchronization
583 						 */
584 	__u32			fwmark;		/* Fire wall mark from skb */
585 	unsigned long		sync_endtime;	/* jiffies + sent_retries */
586 
587 	/* Control members */
588 	struct ip_vs_conn       *control;       /* Master control connection */
589 	atomic_t                n_control;      /* Number of controlled ones */
590 	struct ip_vs_dest       *dest;          /* real server */
591 	atomic_t                in_pkts;        /* incoming packet counter */
592 
593 	/* packet transmitter for different forwarding methods.  If it
594 	   mangles the packet, it must return NF_DROP or better NF_STOLEN,
595 	   otherwise this must be changed to a sk_buff **.
596 	   NF_ACCEPT can be returned when destination is local.
597 	 */
598 	int (*packet_xmit)(struct sk_buff *skb, struct ip_vs_conn *cp,
599 			   struct ip_vs_protocol *pp, struct ip_vs_iphdr *iph);
600 
601 	/* Note: we can group the following members into a structure,
602 	   in order to save more space, and the following members are
603 	   only used in VS/NAT anyway */
604 	struct ip_vs_app        *app;           /* bound ip_vs_app object */
605 	void                    *app_data;      /* Application private data */
606 	struct ip_vs_seq        in_seq;         /* incoming seq. struct */
607 	struct ip_vs_seq        out_seq;        /* outgoing seq. struct */
608 
609 	const struct ip_vs_pe	*pe;
610 	char			*pe_data;
611 	__u8			pe_data_len;
612 
613 	struct rcu_head		rcu_head;
614 };
615 
616 /*
617  *  To save some memory in conn table when name space is disabled.
618  */
619 static inline struct net *ip_vs_conn_net(const struct ip_vs_conn *cp)
620 {
621 #ifdef CONFIG_NET_NS
622 	return cp->net;
623 #else
624 	return &init_net;
625 #endif
626 }
627 static inline void ip_vs_conn_net_set(struct ip_vs_conn *cp, struct net *net)
628 {
629 #ifdef CONFIG_NET_NS
630 	cp->net = net;
631 #endif
632 }
633 
634 static inline int ip_vs_conn_net_eq(const struct ip_vs_conn *cp,
635 				    struct net *net)
636 {
637 #ifdef CONFIG_NET_NS
638 	return cp->net == net;
639 #else
640 	return 1;
641 #endif
642 }
643 
644 /*
645  *	Extended internal versions of struct ip_vs_service_user and
646  *	ip_vs_dest_user for IPv6 support.
647  *
648  *	We need these to conveniently pass around service and destination
649  *	options, but unfortunately, we also need to keep the old definitions to
650  *	maintain userspace backwards compatibility for the setsockopt interface.
651  */
652 struct ip_vs_service_user_kern {
653 	/* virtual service addresses */
654 	u16			af;
655 	u16			protocol;
656 	union nf_inet_addr	addr;		/* virtual ip address */
657 	__be16			port;
658 	u32			fwmark;		/* firwall mark of service */
659 
660 	/* virtual service options */
661 	char			*sched_name;
662 	char			*pe_name;
663 	unsigned int		flags;		/* virtual service flags */
664 	unsigned int		timeout;	/* persistent timeout in sec */
665 	__be32			netmask;	/* persistent netmask or plen */
666 };
667 
668 
669 struct ip_vs_dest_user_kern {
670 	/* destination server address */
671 	union nf_inet_addr	addr;
672 	__be16			port;
673 
674 	/* real server options */
675 	unsigned int		conn_flags;	/* connection flags */
676 	int			weight;		/* destination weight */
677 
678 	/* thresholds for active connections */
679 	u32			u_threshold;	/* upper threshold */
680 	u32			l_threshold;	/* lower threshold */
681 };
682 
683 
684 /*
685  *	The information about the virtual service offered to the net
686  *	and the forwarding entries
687  */
688 struct ip_vs_service {
689 	struct hlist_node	s_list;   /* for normal service table */
690 	struct hlist_node	f_list;   /* for fwmark-based service table */
691 	atomic_t		refcnt;   /* reference counter */
692 
693 	u16			af;       /* address family */
694 	__u16			protocol; /* which protocol (TCP/UDP) */
695 	union nf_inet_addr	addr;	  /* IP address for virtual service */
696 	__be16			port;	  /* port number for the service */
697 	__u32                   fwmark;   /* firewall mark of the service */
698 	unsigned int		flags;	  /* service status flags */
699 	unsigned int		timeout;  /* persistent timeout in ticks */
700 	__be32			netmask;  /* grouping granularity, mask/plen */
701 	struct net		*net;
702 
703 	struct list_head	destinations;  /* real server d-linked list */
704 	__u32			num_dests;     /* number of servers */
705 	struct ip_vs_stats      stats;         /* statistics for the service */
706 
707 	/* for scheduling */
708 	struct ip_vs_scheduler __rcu *scheduler; /* bound scheduler object */
709 	spinlock_t		sched_lock;    /* lock sched_data */
710 	void			*sched_data;   /* scheduler application data */
711 
712 	/* alternate persistence engine */
713 	struct ip_vs_pe __rcu	*pe;
714 
715 	struct rcu_head		rcu_head;
716 };
717 
718 /* Information for cached dst */
719 struct ip_vs_dest_dst {
720 	struct dst_entry	*dst_cache;	/* destination cache entry */
721 	u32			dst_cookie;
722 	union nf_inet_addr	dst_saddr;
723 	struct rcu_head		rcu_head;
724 };
725 
726 /* In grace period after removing */
727 #define IP_VS_DEST_STATE_REMOVING	0x01
728 /*
729  *	The real server destination forwarding entry
730  *	with ip address, port number, and so on.
731  */
732 struct ip_vs_dest {
733 	struct list_head	n_list;   /* for the dests in the service */
734 	struct hlist_node	d_list;   /* for table with all the dests */
735 
736 	u16			af;		/* address family */
737 	__be16			port;		/* port number of the server */
738 	union nf_inet_addr	addr;		/* IP address of the server */
739 	volatile unsigned int	flags;		/* dest status flags */
740 	atomic_t		conn_flags;	/* flags to copy to conn */
741 	atomic_t		weight;		/* server weight */
742 
743 	atomic_t		refcnt;		/* reference counter */
744 	struct ip_vs_stats      stats;          /* statistics */
745 	unsigned long		state;		/* state flags */
746 
747 	/* connection counters and thresholds */
748 	atomic_t		activeconns;	/* active connections */
749 	atomic_t		inactconns;	/* inactive connections */
750 	atomic_t		persistconns;	/* persistent connections */
751 	__u32			u_threshold;	/* upper threshold */
752 	__u32			l_threshold;	/* lower threshold */
753 
754 	/* for destination cache */
755 	spinlock_t		dst_lock;	/* lock of dst_cache */
756 	struct ip_vs_dest_dst __rcu *dest_dst;	/* cached dst info */
757 
758 	/* for virtual service */
759 	struct ip_vs_service	*svc;		/* service it belongs to */
760 	__u16			protocol;	/* which protocol (TCP/UDP) */
761 	__be16			vport;		/* virtual port number */
762 	union nf_inet_addr	vaddr;		/* virtual IP address */
763 	__u32			vfwmark;	/* firewall mark of service */
764 
765 	struct list_head	t_list;		/* in dest_trash */
766 	struct rcu_head		rcu_head;
767 	unsigned int		in_rs_table:1;	/* we are in rs_table */
768 };
769 
770 
771 /*
772  *	The scheduler object
773  */
774 struct ip_vs_scheduler {
775 	struct list_head	n_list;		/* d-linked list head */
776 	char			*name;		/* scheduler name */
777 	atomic_t		refcnt;		/* reference counter */
778 	struct module		*module;	/* THIS_MODULE/NULL */
779 
780 	/* scheduler initializing service */
781 	int (*init_service)(struct ip_vs_service *svc);
782 	/* scheduling service finish */
783 	void (*done_service)(struct ip_vs_service *svc);
784 	/* dest is linked */
785 	int (*add_dest)(struct ip_vs_service *svc, struct ip_vs_dest *dest);
786 	/* dest is unlinked */
787 	int (*del_dest)(struct ip_vs_service *svc, struct ip_vs_dest *dest);
788 	/* dest is updated */
789 	int (*upd_dest)(struct ip_vs_service *svc, struct ip_vs_dest *dest);
790 
791 	/* selecting a server from the given service */
792 	struct ip_vs_dest* (*schedule)(struct ip_vs_service *svc,
793 				       const struct sk_buff *skb,
794 				       struct ip_vs_iphdr *iph);
795 };
796 
797 /* The persistence engine object */
798 struct ip_vs_pe {
799 	struct list_head	n_list;		/* d-linked list head */
800 	char			*name;		/* scheduler name */
801 	atomic_t		refcnt;		/* reference counter */
802 	struct module		*module;	/* THIS_MODULE/NULL */
803 
804 	/* get the connection template, if any */
805 	int (*fill_param)(struct ip_vs_conn_param *p, struct sk_buff *skb);
806 	bool (*ct_match)(const struct ip_vs_conn_param *p,
807 			 struct ip_vs_conn *ct);
808 	u32 (*hashkey_raw)(const struct ip_vs_conn_param *p, u32 initval,
809 			   bool inverse);
810 	int (*show_pe_data)(const struct ip_vs_conn *cp, char *buf);
811 };
812 
813 /*
814  *	The application module object (a.k.a. app incarnation)
815  */
816 struct ip_vs_app {
817 	struct list_head	a_list;		/* member in app list */
818 	int			type;		/* IP_VS_APP_TYPE_xxx */
819 	char			*name;		/* application module name */
820 	__u16			protocol;
821 	struct module		*module;	/* THIS_MODULE/NULL */
822 	struct list_head	incs_list;	/* list of incarnations */
823 
824 	/* members for application incarnations */
825 	struct list_head	p_list;		/* member in proto app list */
826 	struct ip_vs_app	*app;		/* its real application */
827 	__be16			port;		/* port number in net order */
828 	atomic_t		usecnt;		/* usage counter */
829 	struct rcu_head		rcu_head;
830 
831 	/*
832 	 * output hook: Process packet in inout direction, diff set for TCP.
833 	 * Return: 0=Error, 1=Payload Not Mangled/Mangled but checksum is ok,
834 	 *	   2=Mangled but checksum was not updated
835 	 */
836 	int (*pkt_out)(struct ip_vs_app *, struct ip_vs_conn *,
837 		       struct sk_buff *, int *diff);
838 
839 	/*
840 	 * input hook: Process packet in outin direction, diff set for TCP.
841 	 * Return: 0=Error, 1=Payload Not Mangled/Mangled but checksum is ok,
842 	 *	   2=Mangled but checksum was not updated
843 	 */
844 	int (*pkt_in)(struct ip_vs_app *, struct ip_vs_conn *,
845 		      struct sk_buff *, int *diff);
846 
847 	/* ip_vs_app initializer */
848 	int (*init_conn)(struct ip_vs_app *, struct ip_vs_conn *);
849 
850 	/* ip_vs_app finish */
851 	int (*done_conn)(struct ip_vs_app *, struct ip_vs_conn *);
852 
853 
854 	/* not used now */
855 	int (*bind_conn)(struct ip_vs_app *, struct ip_vs_conn *,
856 			 struct ip_vs_protocol *);
857 
858 	void (*unbind_conn)(struct ip_vs_app *, struct ip_vs_conn *);
859 
860 	int *			timeout_table;
861 	int *			timeouts;
862 	int			timeouts_size;
863 
864 	int (*conn_schedule)(struct sk_buff *skb, struct ip_vs_app *app,
865 			     int *verdict, struct ip_vs_conn **cpp);
866 
867 	struct ip_vs_conn *
868 	(*conn_in_get)(const struct sk_buff *skb, struct ip_vs_app *app,
869 		       const struct iphdr *iph, int inverse);
870 
871 	struct ip_vs_conn *
872 	(*conn_out_get)(const struct sk_buff *skb, struct ip_vs_app *app,
873 			const struct iphdr *iph, int inverse);
874 
875 	int (*state_transition)(struct ip_vs_conn *cp, int direction,
876 				const struct sk_buff *skb,
877 				struct ip_vs_app *app);
878 
879 	void (*timeout_change)(struct ip_vs_app *app, int flags);
880 };
881 
882 struct ipvs_master_sync_state {
883 	struct list_head	sync_queue;
884 	struct ip_vs_sync_buff	*sync_buff;
885 	unsigned long		sync_queue_len;
886 	unsigned int		sync_queue_delay;
887 	struct task_struct	*master_thread;
888 	struct delayed_work	master_wakeup_work;
889 	struct netns_ipvs	*ipvs;
890 };
891 
892 /* How much time to keep dests in trash */
893 #define IP_VS_DEST_TRASH_PERIOD		(120 * HZ)
894 
895 /* IPVS in network namespace */
896 struct netns_ipvs {
897 	int			gen;		/* Generation */
898 	int			enable;		/* enable like nf_hooks do */
899 	/*
900 	 *	Hash table: for real service lookups
901 	 */
902 	#define IP_VS_RTAB_BITS 4
903 	#define IP_VS_RTAB_SIZE (1 << IP_VS_RTAB_BITS)
904 	#define IP_VS_RTAB_MASK (IP_VS_RTAB_SIZE - 1)
905 
906 	struct hlist_head	rs_table[IP_VS_RTAB_SIZE];
907 	/* ip_vs_app */
908 	struct list_head	app_list;
909 	/* ip_vs_proto */
910 	#define IP_VS_PROTO_TAB_SIZE	32	/* must be power of 2 */
911 	struct ip_vs_proto_data *proto_data_table[IP_VS_PROTO_TAB_SIZE];
912 	/* ip_vs_proto_tcp */
913 #ifdef CONFIG_IP_VS_PROTO_TCP
914 	#define	TCP_APP_TAB_BITS	4
915 	#define	TCP_APP_TAB_SIZE	(1 << TCP_APP_TAB_BITS)
916 	#define	TCP_APP_TAB_MASK	(TCP_APP_TAB_SIZE - 1)
917 	struct list_head	tcp_apps[TCP_APP_TAB_SIZE];
918 #endif
919 	/* ip_vs_proto_udp */
920 #ifdef CONFIG_IP_VS_PROTO_UDP
921 	#define	UDP_APP_TAB_BITS	4
922 	#define	UDP_APP_TAB_SIZE	(1 << UDP_APP_TAB_BITS)
923 	#define	UDP_APP_TAB_MASK	(UDP_APP_TAB_SIZE - 1)
924 	struct list_head	udp_apps[UDP_APP_TAB_SIZE];
925 #endif
926 	/* ip_vs_proto_sctp */
927 #ifdef CONFIG_IP_VS_PROTO_SCTP
928 	#define SCTP_APP_TAB_BITS	4
929 	#define SCTP_APP_TAB_SIZE	(1 << SCTP_APP_TAB_BITS)
930 	#define SCTP_APP_TAB_MASK	(SCTP_APP_TAB_SIZE - 1)
931 	/* Hash table for SCTP application incarnations	 */
932 	struct list_head	sctp_apps[SCTP_APP_TAB_SIZE];
933 #endif
934 	/* ip_vs_conn */
935 	atomic_t		conn_count;      /*  connection counter */
936 
937 	/* ip_vs_ctl */
938 	struct ip_vs_stats		tot_stats;  /* Statistics & est. */
939 
940 	int			num_services;    /* no of virtual services */
941 
942 	/* Trash for destinations */
943 	struct list_head	dest_trash;
944 	spinlock_t		dest_trash_lock;
945 	struct timer_list	dest_trash_timer; /* expiration timer */
946 	/* Service counters */
947 	atomic_t		ftpsvc_counter;
948 	atomic_t		nullsvc_counter;
949 
950 #ifdef CONFIG_SYSCTL
951 	/* 1/rate drop and drop-entry variables */
952 	struct delayed_work	defense_work;   /* Work handler */
953 	int			drop_rate;
954 	int			drop_counter;
955 	atomic_t		dropentry;
956 	/* locks in ctl.c */
957 	spinlock_t		dropentry_lock;  /* drop entry handling */
958 	spinlock_t		droppacket_lock; /* drop packet handling */
959 	spinlock_t		securetcp_lock;  /* state and timeout tables */
960 
961 	/* sys-ctl struct */
962 	struct ctl_table_header	*sysctl_hdr;
963 	struct ctl_table	*sysctl_tbl;
964 #endif
965 
966 	/* sysctl variables */
967 	int			sysctl_amemthresh;
968 	int			sysctl_am_droprate;
969 	int			sysctl_drop_entry;
970 	int			sysctl_drop_packet;
971 	int			sysctl_secure_tcp;
972 #ifdef CONFIG_IP_VS_NFCT
973 	int			sysctl_conntrack;
974 #endif
975 	int			sysctl_snat_reroute;
976 	int			sysctl_sync_ver;
977 	int			sysctl_sync_ports;
978 	int			sysctl_sync_persist_mode;
979 	unsigned long		sysctl_sync_qlen_max;
980 	int			sysctl_sync_sock_size;
981 	int			sysctl_cache_bypass;
982 	int			sysctl_expire_nodest_conn;
983 	int			sysctl_sloppy_tcp;
984 	int			sysctl_sloppy_sctp;
985 	int			sysctl_expire_quiescent_template;
986 	int			sysctl_sync_threshold[2];
987 	unsigned int		sysctl_sync_refresh_period;
988 	int			sysctl_sync_retries;
989 	int			sysctl_nat_icmp_send;
990 	int			sysctl_pmtu_disc;
991 	int			sysctl_backup_only;
992 
993 	/* ip_vs_lblc */
994 	int			sysctl_lblc_expiration;
995 	struct ctl_table_header	*lblc_ctl_header;
996 	struct ctl_table	*lblc_ctl_table;
997 	/* ip_vs_lblcr */
998 	int			sysctl_lblcr_expiration;
999 	struct ctl_table_header	*lblcr_ctl_header;
1000 	struct ctl_table	*lblcr_ctl_table;
1001 	/* ip_vs_est */
1002 	struct list_head	est_list;	/* estimator list */
1003 	spinlock_t		est_lock;
1004 	struct timer_list	est_timer;	/* Estimation timer */
1005 	/* ip_vs_sync */
1006 	spinlock_t		sync_lock;
1007 	struct ipvs_master_sync_state *ms;
1008 	spinlock_t		sync_buff_lock;
1009 	struct task_struct	**backup_threads;
1010 	int			threads_mask;
1011 	int			send_mesg_maxlen;
1012 	int			recv_mesg_maxlen;
1013 	volatile int		sync_state;
1014 	volatile int		master_syncid;
1015 	volatile int		backup_syncid;
1016 	struct mutex		sync_mutex;
1017 	/* multicast interface name */
1018 	char			master_mcast_ifn[IP_VS_IFNAME_MAXLEN];
1019 	char			backup_mcast_ifn[IP_VS_IFNAME_MAXLEN];
1020 	/* net name space ptr */
1021 	struct net		*net;            /* Needed by timer routines */
1022 };
1023 
1024 #define DEFAULT_SYNC_THRESHOLD	3
1025 #define DEFAULT_SYNC_PERIOD	50
1026 #define DEFAULT_SYNC_VER	1
1027 #define DEFAULT_SLOPPY_TCP	0
1028 #define DEFAULT_SLOPPY_SCTP	0
1029 #define DEFAULT_SYNC_REFRESH_PERIOD	(0U * HZ)
1030 #define DEFAULT_SYNC_RETRIES		0
1031 #define IPVS_SYNC_WAKEUP_RATE	8
1032 #define IPVS_SYNC_QLEN_MAX	(IPVS_SYNC_WAKEUP_RATE * 4)
1033 #define IPVS_SYNC_SEND_DELAY	(HZ / 50)
1034 #define IPVS_SYNC_CHECK_PERIOD	HZ
1035 #define IPVS_SYNC_FLUSH_TIME	(HZ * 2)
1036 #define IPVS_SYNC_PORTS_MAX	(1 << 6)
1037 
1038 #ifdef CONFIG_SYSCTL
1039 
1040 static inline int sysctl_sync_threshold(struct netns_ipvs *ipvs)
1041 {
1042 	return ipvs->sysctl_sync_threshold[0];
1043 }
1044 
1045 static inline int sysctl_sync_period(struct netns_ipvs *ipvs)
1046 {
1047 	return ACCESS_ONCE(ipvs->sysctl_sync_threshold[1]);
1048 }
1049 
1050 static inline unsigned int sysctl_sync_refresh_period(struct netns_ipvs *ipvs)
1051 {
1052 	return ACCESS_ONCE(ipvs->sysctl_sync_refresh_period);
1053 }
1054 
1055 static inline int sysctl_sync_retries(struct netns_ipvs *ipvs)
1056 {
1057 	return ipvs->sysctl_sync_retries;
1058 }
1059 
1060 static inline int sysctl_sync_ver(struct netns_ipvs *ipvs)
1061 {
1062 	return ipvs->sysctl_sync_ver;
1063 }
1064 
1065 static inline int sysctl_sloppy_tcp(struct netns_ipvs *ipvs)
1066 {
1067 	return ipvs->sysctl_sloppy_tcp;
1068 }
1069 
1070 static inline int sysctl_sloppy_sctp(struct netns_ipvs *ipvs)
1071 {
1072 	return ipvs->sysctl_sloppy_sctp;
1073 }
1074 
1075 static inline int sysctl_sync_ports(struct netns_ipvs *ipvs)
1076 {
1077 	return ACCESS_ONCE(ipvs->sysctl_sync_ports);
1078 }
1079 
1080 static inline int sysctl_sync_persist_mode(struct netns_ipvs *ipvs)
1081 {
1082 	return ipvs->sysctl_sync_persist_mode;
1083 }
1084 
1085 static inline unsigned long sysctl_sync_qlen_max(struct netns_ipvs *ipvs)
1086 {
1087 	return ipvs->sysctl_sync_qlen_max;
1088 }
1089 
1090 static inline int sysctl_sync_sock_size(struct netns_ipvs *ipvs)
1091 {
1092 	return ipvs->sysctl_sync_sock_size;
1093 }
1094 
1095 static inline int sysctl_pmtu_disc(struct netns_ipvs *ipvs)
1096 {
1097 	return ipvs->sysctl_pmtu_disc;
1098 }
1099 
1100 static inline int sysctl_backup_only(struct netns_ipvs *ipvs)
1101 {
1102 	return ipvs->sync_state & IP_VS_STATE_BACKUP &&
1103 	       ipvs->sysctl_backup_only;
1104 }
1105 
1106 #else
1107 
1108 static inline int sysctl_sync_threshold(struct netns_ipvs *ipvs)
1109 {
1110 	return DEFAULT_SYNC_THRESHOLD;
1111 }
1112 
1113 static inline int sysctl_sync_period(struct netns_ipvs *ipvs)
1114 {
1115 	return DEFAULT_SYNC_PERIOD;
1116 }
1117 
1118 static inline unsigned int sysctl_sync_refresh_period(struct netns_ipvs *ipvs)
1119 {
1120 	return DEFAULT_SYNC_REFRESH_PERIOD;
1121 }
1122 
1123 static inline int sysctl_sync_retries(struct netns_ipvs *ipvs)
1124 {
1125 	return DEFAULT_SYNC_RETRIES & 3;
1126 }
1127 
1128 static inline int sysctl_sync_ver(struct netns_ipvs *ipvs)
1129 {
1130 	return DEFAULT_SYNC_VER;
1131 }
1132 
1133 static inline int sysctl_sloppy_tcp(struct netns_ipvs *ipvs)
1134 {
1135 	return DEFAULT_SLOPPY_TCP;
1136 }
1137 
1138 static inline int sysctl_sloppy_sctp(struct netns_ipvs *ipvs)
1139 {
1140 	return DEFAULT_SLOPPY_SCTP;
1141 }
1142 
1143 static inline int sysctl_sync_ports(struct netns_ipvs *ipvs)
1144 {
1145 	return 1;
1146 }
1147 
1148 static inline int sysctl_sync_persist_mode(struct netns_ipvs *ipvs)
1149 {
1150 	return 0;
1151 }
1152 
1153 static inline unsigned long sysctl_sync_qlen_max(struct netns_ipvs *ipvs)
1154 {
1155 	return IPVS_SYNC_QLEN_MAX;
1156 }
1157 
1158 static inline int sysctl_sync_sock_size(struct netns_ipvs *ipvs)
1159 {
1160 	return 0;
1161 }
1162 
1163 static inline int sysctl_pmtu_disc(struct netns_ipvs *ipvs)
1164 {
1165 	return 1;
1166 }
1167 
1168 static inline int sysctl_backup_only(struct netns_ipvs *ipvs)
1169 {
1170 	return 0;
1171 }
1172 
1173 #endif
1174 
1175 /*
1176  *      IPVS core functions
1177  *      (from ip_vs_core.c)
1178  */
1179 extern const char *ip_vs_proto_name(unsigned int proto);
1180 extern void ip_vs_init_hash_table(struct list_head *table, int rows);
1181 #define IP_VS_INIT_HASH_TABLE(t) ip_vs_init_hash_table((t), ARRAY_SIZE((t)))
1182 
1183 #define IP_VS_APP_TYPE_FTP	1
1184 
1185 /*
1186  *     ip_vs_conn handling functions
1187  *     (from ip_vs_conn.c)
1188  */
1189 
1190 enum {
1191 	IP_VS_DIR_INPUT = 0,
1192 	IP_VS_DIR_OUTPUT,
1193 	IP_VS_DIR_INPUT_ONLY,
1194 	IP_VS_DIR_LAST,
1195 };
1196 
1197 static inline void ip_vs_conn_fill_param(struct net *net, int af, int protocol,
1198 					 const union nf_inet_addr *caddr,
1199 					 __be16 cport,
1200 					 const union nf_inet_addr *vaddr,
1201 					 __be16 vport,
1202 					 struct ip_vs_conn_param *p)
1203 {
1204 	p->net = net;
1205 	p->af = af;
1206 	p->protocol = protocol;
1207 	p->caddr = caddr;
1208 	p->cport = cport;
1209 	p->vaddr = vaddr;
1210 	p->vport = vport;
1211 	p->pe = NULL;
1212 	p->pe_data = NULL;
1213 }
1214 
1215 struct ip_vs_conn *ip_vs_conn_in_get(const struct ip_vs_conn_param *p);
1216 struct ip_vs_conn *ip_vs_ct_in_get(const struct ip_vs_conn_param *p);
1217 
1218 struct ip_vs_conn * ip_vs_conn_in_get_proto(int af, const struct sk_buff *skb,
1219 					    const struct ip_vs_iphdr *iph,
1220 					    int inverse);
1221 
1222 struct ip_vs_conn *ip_vs_conn_out_get(const struct ip_vs_conn_param *p);
1223 
1224 struct ip_vs_conn * ip_vs_conn_out_get_proto(int af, const struct sk_buff *skb,
1225 					     const struct ip_vs_iphdr *iph,
1226 					     int inverse);
1227 
1228 /* Get reference to gain full access to conn.
1229  * By default, RCU read-side critical sections have access only to
1230  * conn fields and its PE data, see ip_vs_conn_rcu_free() for reference.
1231  */
1232 static inline bool __ip_vs_conn_get(struct ip_vs_conn *cp)
1233 {
1234 	return atomic_inc_not_zero(&cp->refcnt);
1235 }
1236 
1237 /* put back the conn without restarting its timer */
1238 static inline void __ip_vs_conn_put(struct ip_vs_conn *cp)
1239 {
1240 	smp_mb__before_atomic_dec();
1241 	atomic_dec(&cp->refcnt);
1242 }
1243 extern void ip_vs_conn_put(struct ip_vs_conn *cp);
1244 extern void ip_vs_conn_fill_cport(struct ip_vs_conn *cp, __be16 cport);
1245 
1246 struct ip_vs_conn *ip_vs_conn_new(const struct ip_vs_conn_param *p,
1247 				  const union nf_inet_addr *daddr,
1248 				  __be16 dport, unsigned int flags,
1249 				  struct ip_vs_dest *dest, __u32 fwmark);
1250 extern void ip_vs_conn_expire_now(struct ip_vs_conn *cp);
1251 
1252 extern const char * ip_vs_state_name(__u16 proto, int state);
1253 
1254 extern void ip_vs_tcp_conn_listen(struct net *net, struct ip_vs_conn *cp);
1255 extern int ip_vs_check_template(struct ip_vs_conn *ct);
1256 extern void ip_vs_random_dropentry(struct net *net);
1257 extern int ip_vs_conn_init(void);
1258 extern void ip_vs_conn_cleanup(void);
1259 
1260 static inline void ip_vs_control_del(struct ip_vs_conn *cp)
1261 {
1262 	struct ip_vs_conn *ctl_cp = cp->control;
1263 	if (!ctl_cp) {
1264 		IP_VS_ERR_BUF("request control DEL for uncontrolled: "
1265 			      "%s:%d to %s:%d\n",
1266 			      IP_VS_DBG_ADDR(cp->af, &cp->caddr),
1267 			      ntohs(cp->cport),
1268 			      IP_VS_DBG_ADDR(cp->af, &cp->vaddr),
1269 			      ntohs(cp->vport));
1270 
1271 		return;
1272 	}
1273 
1274 	IP_VS_DBG_BUF(7, "DELeting control for: "
1275 		      "cp.dst=%s:%d ctl_cp.dst=%s:%d\n",
1276 		      IP_VS_DBG_ADDR(cp->af, &cp->caddr),
1277 		      ntohs(cp->cport),
1278 		      IP_VS_DBG_ADDR(cp->af, &ctl_cp->caddr),
1279 		      ntohs(ctl_cp->cport));
1280 
1281 	cp->control = NULL;
1282 	if (atomic_read(&ctl_cp->n_control) == 0) {
1283 		IP_VS_ERR_BUF("BUG control DEL with n=0 : "
1284 			      "%s:%d to %s:%d\n",
1285 			      IP_VS_DBG_ADDR(cp->af, &cp->caddr),
1286 			      ntohs(cp->cport),
1287 			      IP_VS_DBG_ADDR(cp->af, &cp->vaddr),
1288 			      ntohs(cp->vport));
1289 
1290 		return;
1291 	}
1292 	atomic_dec(&ctl_cp->n_control);
1293 }
1294 
1295 static inline void
1296 ip_vs_control_add(struct ip_vs_conn *cp, struct ip_vs_conn *ctl_cp)
1297 {
1298 	if (cp->control) {
1299 		IP_VS_ERR_BUF("request control ADD for already controlled: "
1300 			      "%s:%d to %s:%d\n",
1301 			      IP_VS_DBG_ADDR(cp->af, &cp->caddr),
1302 			      ntohs(cp->cport),
1303 			      IP_VS_DBG_ADDR(cp->af, &cp->vaddr),
1304 			      ntohs(cp->vport));
1305 
1306 		ip_vs_control_del(cp);
1307 	}
1308 
1309 	IP_VS_DBG_BUF(7, "ADDing control for: "
1310 		      "cp.dst=%s:%d ctl_cp.dst=%s:%d\n",
1311 		      IP_VS_DBG_ADDR(cp->af, &cp->caddr),
1312 		      ntohs(cp->cport),
1313 		      IP_VS_DBG_ADDR(cp->af, &ctl_cp->caddr),
1314 		      ntohs(ctl_cp->cport));
1315 
1316 	cp->control = ctl_cp;
1317 	atomic_inc(&ctl_cp->n_control);
1318 }
1319 
1320 /*
1321  * IPVS netns init & cleanup functions
1322  */
1323 extern int ip_vs_estimator_net_init(struct net *net);
1324 extern int ip_vs_control_net_init(struct net *net);
1325 extern int ip_vs_protocol_net_init(struct net *net);
1326 extern int ip_vs_app_net_init(struct net *net);
1327 extern int ip_vs_conn_net_init(struct net *net);
1328 extern int ip_vs_sync_net_init(struct net *net);
1329 extern void ip_vs_conn_net_cleanup(struct net *net);
1330 extern void ip_vs_app_net_cleanup(struct net *net);
1331 extern void ip_vs_protocol_net_cleanup(struct net *net);
1332 extern void ip_vs_control_net_cleanup(struct net *net);
1333 extern void ip_vs_estimator_net_cleanup(struct net *net);
1334 extern void ip_vs_sync_net_cleanup(struct net *net);
1335 extern void ip_vs_service_net_cleanup(struct net *net);
1336 
1337 /*
1338  *      IPVS application functions
1339  *      (from ip_vs_app.c)
1340  */
1341 #define IP_VS_APP_MAX_PORTS  8
1342 extern struct ip_vs_app *register_ip_vs_app(struct net *net,
1343 					    struct ip_vs_app *app);
1344 extern void unregister_ip_vs_app(struct net *net, struct ip_vs_app *app);
1345 extern int ip_vs_bind_app(struct ip_vs_conn *cp, struct ip_vs_protocol *pp);
1346 extern void ip_vs_unbind_app(struct ip_vs_conn *cp);
1347 extern int register_ip_vs_app_inc(struct net *net, struct ip_vs_app *app,
1348 				  __u16 proto, __u16 port);
1349 extern int ip_vs_app_inc_get(struct ip_vs_app *inc);
1350 extern void ip_vs_app_inc_put(struct ip_vs_app *inc);
1351 
1352 extern int ip_vs_app_pkt_out(struct ip_vs_conn *, struct sk_buff *skb);
1353 extern int ip_vs_app_pkt_in(struct ip_vs_conn *, struct sk_buff *skb);
1354 
1355 int register_ip_vs_pe(struct ip_vs_pe *pe);
1356 int unregister_ip_vs_pe(struct ip_vs_pe *pe);
1357 struct ip_vs_pe *ip_vs_pe_getbyname(const char *name);
1358 struct ip_vs_pe *__ip_vs_pe_getbyname(const char *pe_name);
1359 
1360 /*
1361  * Use a #define to avoid all of module.h just for these trivial ops
1362  */
1363 #define ip_vs_pe_get(pe)			\
1364 	if (pe && pe->module)			\
1365 		__module_get(pe->module);
1366 
1367 #define ip_vs_pe_put(pe)			\
1368 	if (pe && pe->module)			\
1369 		module_put(pe->module);
1370 
1371 /*
1372  *	IPVS protocol functions (from ip_vs_proto.c)
1373  */
1374 extern int ip_vs_protocol_init(void);
1375 extern void ip_vs_protocol_cleanup(void);
1376 extern void ip_vs_protocol_timeout_change(struct netns_ipvs *ipvs, int flags);
1377 extern int *ip_vs_create_timeout_table(int *table, int size);
1378 extern int
1379 ip_vs_set_state_timeout(int *table, int num, const char *const *names,
1380 			const char *name, int to);
1381 extern void
1382 ip_vs_tcpudp_debug_packet(int af, struct ip_vs_protocol *pp,
1383 			  const struct sk_buff *skb,
1384 			  int offset, const char *msg);
1385 
1386 extern struct ip_vs_protocol ip_vs_protocol_tcp;
1387 extern struct ip_vs_protocol ip_vs_protocol_udp;
1388 extern struct ip_vs_protocol ip_vs_protocol_icmp;
1389 extern struct ip_vs_protocol ip_vs_protocol_esp;
1390 extern struct ip_vs_protocol ip_vs_protocol_ah;
1391 extern struct ip_vs_protocol ip_vs_protocol_sctp;
1392 
1393 /*
1394  *      Registering/unregistering scheduler functions
1395  *      (from ip_vs_sched.c)
1396  */
1397 extern int register_ip_vs_scheduler(struct ip_vs_scheduler *scheduler);
1398 extern int unregister_ip_vs_scheduler(struct ip_vs_scheduler *scheduler);
1399 extern int ip_vs_bind_scheduler(struct ip_vs_service *svc,
1400 				struct ip_vs_scheduler *scheduler);
1401 extern void ip_vs_unbind_scheduler(struct ip_vs_service *svc,
1402 				   struct ip_vs_scheduler *sched);
1403 extern struct ip_vs_scheduler *ip_vs_scheduler_get(const char *sched_name);
1404 extern void ip_vs_scheduler_put(struct ip_vs_scheduler *scheduler);
1405 extern struct ip_vs_conn *
1406 ip_vs_schedule(struct ip_vs_service *svc, struct sk_buff *skb,
1407 	       struct ip_vs_proto_data *pd, int *ignored,
1408 	       struct ip_vs_iphdr *iph);
1409 extern int ip_vs_leave(struct ip_vs_service *svc, struct sk_buff *skb,
1410 			struct ip_vs_proto_data *pd, struct ip_vs_iphdr *iph);
1411 
1412 extern void ip_vs_scheduler_err(struct ip_vs_service *svc, const char *msg);
1413 
1414 
1415 /*
1416  *      IPVS control data and functions (from ip_vs_ctl.c)
1417  */
1418 extern struct ip_vs_stats ip_vs_stats;
1419 extern int sysctl_ip_vs_sync_ver;
1420 
1421 extern struct ip_vs_service *
1422 ip_vs_service_find(struct net *net, int af, __u32 fwmark, __u16 protocol,
1423 		  const union nf_inet_addr *vaddr, __be16 vport);
1424 
1425 extern bool
1426 ip_vs_has_real_service(struct net *net, int af, __u16 protocol,
1427 		       const union nf_inet_addr *daddr, __be16 dport);
1428 
1429 extern int ip_vs_use_count_inc(void);
1430 extern void ip_vs_use_count_dec(void);
1431 extern int ip_vs_register_nl_ioctl(void);
1432 extern void ip_vs_unregister_nl_ioctl(void);
1433 extern int ip_vs_control_init(void);
1434 extern void ip_vs_control_cleanup(void);
1435 extern struct ip_vs_dest *
1436 ip_vs_find_dest(struct net *net, int af, const union nf_inet_addr *daddr,
1437 		__be16 dport, const union nf_inet_addr *vaddr, __be16 vport,
1438 		__u16 protocol, __u32 fwmark, __u32 flags);
1439 extern void ip_vs_try_bind_dest(struct ip_vs_conn *cp);
1440 
1441 static inline void ip_vs_dest_hold(struct ip_vs_dest *dest)
1442 {
1443 	atomic_inc(&dest->refcnt);
1444 }
1445 
1446 static inline void ip_vs_dest_put(struct ip_vs_dest *dest)
1447 {
1448 	smp_mb__before_atomic_dec();
1449 	atomic_dec(&dest->refcnt);
1450 }
1451 
1452 /*
1453  *      IPVS sync daemon data and function prototypes
1454  *      (from ip_vs_sync.c)
1455  */
1456 extern int start_sync_thread(struct net *net, int state, char *mcast_ifn,
1457 			     __u8 syncid);
1458 extern int stop_sync_thread(struct net *net, int state);
1459 extern void ip_vs_sync_conn(struct net *net, struct ip_vs_conn *cp, int pkts);
1460 
1461 
1462 /*
1463  *      IPVS rate estimator prototypes (from ip_vs_est.c)
1464  */
1465 extern void ip_vs_start_estimator(struct net *net, struct ip_vs_stats *stats);
1466 extern void ip_vs_stop_estimator(struct net *net, struct ip_vs_stats *stats);
1467 extern void ip_vs_zero_estimator(struct ip_vs_stats *stats);
1468 extern void ip_vs_read_estimator(struct ip_vs_stats_user *dst,
1469 				 struct ip_vs_stats *stats);
1470 
1471 /*
1472  *	Various IPVS packet transmitters (from ip_vs_xmit.c)
1473  */
1474 extern int ip_vs_null_xmit(struct sk_buff *skb, struct ip_vs_conn *cp,
1475 			   struct ip_vs_protocol *pp, struct ip_vs_iphdr *iph);
1476 extern int ip_vs_bypass_xmit(struct sk_buff *skb, struct ip_vs_conn *cp,
1477 			     struct ip_vs_protocol *pp,
1478 			     struct ip_vs_iphdr *iph);
1479 extern int ip_vs_nat_xmit(struct sk_buff *skb, struct ip_vs_conn *cp,
1480 			  struct ip_vs_protocol *pp, struct ip_vs_iphdr *iph);
1481 extern int ip_vs_tunnel_xmit(struct sk_buff *skb, struct ip_vs_conn *cp,
1482 			     struct ip_vs_protocol *pp,
1483 			     struct ip_vs_iphdr *iph);
1484 extern int ip_vs_dr_xmit(struct sk_buff *skb, struct ip_vs_conn *cp,
1485 			 struct ip_vs_protocol *pp, struct ip_vs_iphdr *iph);
1486 extern int ip_vs_icmp_xmit(struct sk_buff *skb, struct ip_vs_conn *cp,
1487 			   struct ip_vs_protocol *pp, int offset,
1488 			   unsigned int hooknum, struct ip_vs_iphdr *iph);
1489 extern void ip_vs_dest_dst_rcu_free(struct rcu_head *head);
1490 
1491 #ifdef CONFIG_IP_VS_IPV6
1492 extern int ip_vs_bypass_xmit_v6(struct sk_buff *skb, struct ip_vs_conn *cp,
1493 				struct ip_vs_protocol *pp,
1494 				struct ip_vs_iphdr *iph);
1495 extern int ip_vs_nat_xmit_v6(struct sk_buff *skb, struct ip_vs_conn *cp,
1496 			     struct ip_vs_protocol *pp,
1497 			     struct ip_vs_iphdr *iph);
1498 extern int ip_vs_tunnel_xmit_v6(struct sk_buff *skb, struct ip_vs_conn *cp,
1499 				struct ip_vs_protocol *pp,
1500 				struct ip_vs_iphdr *iph);
1501 extern int ip_vs_dr_xmit_v6(struct sk_buff *skb, struct ip_vs_conn *cp,
1502 			    struct ip_vs_protocol *pp, struct ip_vs_iphdr *iph);
1503 extern int ip_vs_icmp_xmit_v6(struct sk_buff *skb, struct ip_vs_conn *cp,
1504 			      struct ip_vs_protocol *pp, int offset,
1505 			      unsigned int hooknum, struct ip_vs_iphdr *iph);
1506 #endif
1507 
1508 #ifdef CONFIG_SYSCTL
1509 /*
1510  *	This is a simple mechanism to ignore packets when
1511  *	we are loaded. Just set ip_vs_drop_rate to 'n' and
1512  *	we start to drop 1/rate of the packets
1513  */
1514 
1515 static inline int ip_vs_todrop(struct netns_ipvs *ipvs)
1516 {
1517 	if (!ipvs->drop_rate)
1518 		return 0;
1519 	if (--ipvs->drop_counter > 0)
1520 		return 0;
1521 	ipvs->drop_counter = ipvs->drop_rate;
1522 	return 1;
1523 }
1524 #else
1525 static inline int ip_vs_todrop(struct netns_ipvs *ipvs) { return 0; }
1526 #endif
1527 
1528 /*
1529  *      ip_vs_fwd_tag returns the forwarding tag of the connection
1530  */
1531 #define IP_VS_FWD_METHOD(cp)  (cp->flags & IP_VS_CONN_F_FWD_MASK)
1532 
1533 static inline char ip_vs_fwd_tag(struct ip_vs_conn *cp)
1534 {
1535 	char fwd;
1536 
1537 	switch (IP_VS_FWD_METHOD(cp)) {
1538 	case IP_VS_CONN_F_MASQ:
1539 		fwd = 'M'; break;
1540 	case IP_VS_CONN_F_LOCALNODE:
1541 		fwd = 'L'; break;
1542 	case IP_VS_CONN_F_TUNNEL:
1543 		fwd = 'T'; break;
1544 	case IP_VS_CONN_F_DROUTE:
1545 		fwd = 'R'; break;
1546 	case IP_VS_CONN_F_BYPASS:
1547 		fwd = 'B'; break;
1548 	default:
1549 		fwd = '?'; break;
1550 	}
1551 	return fwd;
1552 }
1553 
1554 extern void ip_vs_nat_icmp(struct sk_buff *skb, struct ip_vs_protocol *pp,
1555 			   struct ip_vs_conn *cp, int dir);
1556 
1557 #ifdef CONFIG_IP_VS_IPV6
1558 extern void ip_vs_nat_icmp_v6(struct sk_buff *skb, struct ip_vs_protocol *pp,
1559 			      struct ip_vs_conn *cp, int dir);
1560 #endif
1561 
1562 extern __sum16 ip_vs_checksum_complete(struct sk_buff *skb, int offset);
1563 
1564 static inline __wsum ip_vs_check_diff4(__be32 old, __be32 new, __wsum oldsum)
1565 {
1566 	__be32 diff[2] = { ~old, new };
1567 
1568 	return csum_partial(diff, sizeof(diff), oldsum);
1569 }
1570 
1571 #ifdef CONFIG_IP_VS_IPV6
1572 static inline __wsum ip_vs_check_diff16(const __be32 *old, const __be32 *new,
1573 					__wsum oldsum)
1574 {
1575 	__be32 diff[8] = { ~old[3], ~old[2], ~old[1], ~old[0],
1576 			    new[3],  new[2],  new[1],  new[0] };
1577 
1578 	return csum_partial(diff, sizeof(diff), oldsum);
1579 }
1580 #endif
1581 
1582 static inline __wsum ip_vs_check_diff2(__be16 old, __be16 new, __wsum oldsum)
1583 {
1584 	__be16 diff[2] = { ~old, new };
1585 
1586 	return csum_partial(diff, sizeof(diff), oldsum);
1587 }
1588 
1589 /*
1590  * Forget current conntrack (unconfirmed) and attach notrack entry
1591  */
1592 static inline void ip_vs_notrack(struct sk_buff *skb)
1593 {
1594 #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
1595 	enum ip_conntrack_info ctinfo;
1596 	struct nf_conn *ct = nf_ct_get(skb, &ctinfo);
1597 
1598 	if (!ct || !nf_ct_is_untracked(ct)) {
1599 		nf_conntrack_put(skb->nfct);
1600 		skb->nfct = &nf_ct_untracked_get()->ct_general;
1601 		skb->nfctinfo = IP_CT_NEW;
1602 		nf_conntrack_get(skb->nfct);
1603 	}
1604 #endif
1605 }
1606 
1607 #ifdef CONFIG_IP_VS_NFCT
1608 /*
1609  *      Netfilter connection tracking
1610  *      (from ip_vs_nfct.c)
1611  */
1612 static inline int ip_vs_conntrack_enabled(struct netns_ipvs *ipvs)
1613 {
1614 #ifdef CONFIG_SYSCTL
1615 	return ipvs->sysctl_conntrack;
1616 #else
1617 	return 0;
1618 #endif
1619 }
1620 
1621 extern void ip_vs_update_conntrack(struct sk_buff *skb, struct ip_vs_conn *cp,
1622 				   int outin);
1623 extern int ip_vs_confirm_conntrack(struct sk_buff *skb);
1624 extern void ip_vs_nfct_expect_related(struct sk_buff *skb, struct nf_conn *ct,
1625 				      struct ip_vs_conn *cp, u_int8_t proto,
1626 				      const __be16 port, int from_rs);
1627 extern void ip_vs_conn_drop_conntrack(struct ip_vs_conn *cp);
1628 
1629 #else
1630 
1631 static inline int ip_vs_conntrack_enabled(struct netns_ipvs *ipvs)
1632 {
1633 	return 0;
1634 }
1635 
1636 static inline void ip_vs_update_conntrack(struct sk_buff *skb,
1637 					  struct ip_vs_conn *cp, int outin)
1638 {
1639 }
1640 
1641 static inline int ip_vs_confirm_conntrack(struct sk_buff *skb)
1642 {
1643 	return NF_ACCEPT;
1644 }
1645 
1646 static inline void ip_vs_conn_drop_conntrack(struct ip_vs_conn *cp)
1647 {
1648 }
1649 /* CONFIG_IP_VS_NFCT */
1650 #endif
1651 
1652 static inline unsigned int
1653 ip_vs_dest_conn_overhead(struct ip_vs_dest *dest)
1654 {
1655 	/*
1656 	 * We think the overhead of processing active connections is 256
1657 	 * times higher than that of inactive connections in average. (This
1658 	 * 256 times might not be accurate, we will change it later) We
1659 	 * use the following formula to estimate the overhead now:
1660 	 *		  dest->activeconns*256 + dest->inactconns
1661 	 */
1662 	return (atomic_read(&dest->activeconns) << 8) +
1663 		atomic_read(&dest->inactconns);
1664 }
1665 
1666 #endif	/* _NET_IP_VS_H */
1667