xref: /linux/include/net/ip_vs.h (revision c54ea4918c2b7722d7242ea53271356501988a9b)
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 /* old ipvsadm versions still include this file directly */
12 #ifdef __KERNEL__
13 
14 #include <asm/types.h>                  /* for __uXX types */
15 
16 #include <linux/sysctl.h>               /* for ctl_path */
17 #include <linux/list.h>                 /* for struct list_head */
18 #include <linux/spinlock.h>             /* for struct rwlock_t */
19 #include <asm/atomic.h>                 /* for struct atomic_t */
20 #include <linux/compiler.h>
21 #include <linux/timer.h>
22 
23 #include <net/checksum.h>
24 #include <linux/netfilter.h>		/* for union nf_inet_addr */
25 #include <linux/ip.h>
26 #include <linux/ipv6.h>			/* for struct ipv6hdr */
27 #include <net/ipv6.h>			/* for ipv6_addr_copy */
28 #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
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)->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 cant 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 
110 struct ip_vs_iphdr {
111 	int len;
112 	__u8 protocol;
113 	union nf_inet_addr saddr;
114 	union nf_inet_addr daddr;
115 };
116 
117 static inline void
118 ip_vs_fill_iphdr(int af, const void *nh, struct ip_vs_iphdr *iphdr)
119 {
120 #ifdef CONFIG_IP_VS_IPV6
121 	if (af == AF_INET6) {
122 		const struct ipv6hdr *iph = nh;
123 		iphdr->len = sizeof(struct ipv6hdr);
124 		iphdr->protocol = iph->nexthdr;
125 		ipv6_addr_copy(&iphdr->saddr.in6, &iph->saddr);
126 		ipv6_addr_copy(&iphdr->daddr.in6, &iph->daddr);
127 	} else
128 #endif
129 	{
130 		const struct iphdr *iph = nh;
131 		iphdr->len = iph->ihl * 4;
132 		iphdr->protocol = iph->protocol;
133 		iphdr->saddr.ip = iph->saddr;
134 		iphdr->daddr.ip = iph->daddr;
135 	}
136 }
137 
138 static inline void ip_vs_addr_copy(int af, union nf_inet_addr *dst,
139 				   const union nf_inet_addr *src)
140 {
141 #ifdef CONFIG_IP_VS_IPV6
142 	if (af == AF_INET6)
143 		ipv6_addr_copy(&dst->in6, &src->in6);
144 	else
145 #endif
146 	dst->ip = src->ip;
147 }
148 
149 static inline int ip_vs_addr_equal(int af, const union nf_inet_addr *a,
150 				   const union nf_inet_addr *b)
151 {
152 #ifdef CONFIG_IP_VS_IPV6
153 	if (af == AF_INET6)
154 		return ipv6_addr_equal(&a->in6, &b->in6);
155 #endif
156 	return a->ip == b->ip;
157 }
158 
159 #ifdef CONFIG_IP_VS_DEBUG
160 #include <linux/net.h>
161 
162 extern int ip_vs_get_debug_level(void);
163 
164 static inline const char *ip_vs_dbg_addr(int af, char *buf, size_t buf_len,
165 					 const union nf_inet_addr *addr,
166 					 int *idx)
167 {
168 	int len;
169 #ifdef CONFIG_IP_VS_IPV6
170 	if (af == AF_INET6)
171 		len = snprintf(&buf[*idx], buf_len - *idx, "[%pI6]",
172 			       &addr->in6) + 1;
173 	else
174 #endif
175 		len = snprintf(&buf[*idx], buf_len - *idx, "%pI4",
176 			       &addr->ip) + 1;
177 
178 	*idx += len;
179 	BUG_ON(*idx > buf_len + 1);
180 	return &buf[*idx - len];
181 }
182 
183 #define IP_VS_DBG_BUF(level, msg, ...)					\
184 	do {								\
185 		char ip_vs_dbg_buf[160];				\
186 		int ip_vs_dbg_idx = 0;					\
187 		if (level <= ip_vs_get_debug_level())			\
188 			printk(KERN_DEBUG pr_fmt(msg), ##__VA_ARGS__);	\
189 	} while (0)
190 #define IP_VS_ERR_BUF(msg...)						\
191 	do {								\
192 		char ip_vs_dbg_buf[160];				\
193 		int ip_vs_dbg_idx = 0;					\
194 		pr_err(msg);						\
195 	} while (0)
196 
197 /* Only use from within IP_VS_DBG_BUF() or IP_VS_ERR_BUF macros */
198 #define IP_VS_DBG_ADDR(af, addr)					\
199 	ip_vs_dbg_addr(af, ip_vs_dbg_buf,				\
200 		       sizeof(ip_vs_dbg_buf), addr,			\
201 		       &ip_vs_dbg_idx)
202 
203 #define IP_VS_DBG(level, msg, ...)					\
204 	do {								\
205 		if (level <= ip_vs_get_debug_level())			\
206 			printk(KERN_DEBUG pr_fmt(msg), ##__VA_ARGS__);	\
207 	} while (0)
208 #define IP_VS_DBG_RL(msg, ...)						\
209 	do {								\
210 		if (net_ratelimit())					\
211 			printk(KERN_DEBUG pr_fmt(msg), ##__VA_ARGS__);	\
212 	} while (0)
213 #define IP_VS_DBG_PKT(level, af, pp, skb, ofs, msg)			\
214 	do {								\
215 		if (level <= ip_vs_get_debug_level())			\
216 			pp->debug_packet(af, pp, skb, ofs, msg);	\
217 	} while (0)
218 #define IP_VS_DBG_RL_PKT(level, af, pp, skb, ofs, msg)			\
219 	do {								\
220 		if (level <= ip_vs_get_debug_level() &&			\
221 		    net_ratelimit())					\
222 			pp->debug_packet(af, pp, skb, ofs, msg);	\
223 	} while (0)
224 #else	/* NO DEBUGGING at ALL */
225 #define IP_VS_DBG_BUF(level, msg...)  do {} while (0)
226 #define IP_VS_ERR_BUF(msg...)  do {} while (0)
227 #define IP_VS_DBG(level, msg...)  do {} while (0)
228 #define IP_VS_DBG_RL(msg...)  do {} while (0)
229 #define IP_VS_DBG_PKT(level, af, pp, skb, ofs, msg)	do {} while (0)
230 #define IP_VS_DBG_RL_PKT(level, af, pp, skb, ofs, msg)	do {} while (0)
231 #endif
232 
233 #define IP_VS_BUG() BUG()
234 #define IP_VS_ERR_RL(msg, ...)						\
235 	do {								\
236 		if (net_ratelimit())					\
237 			pr_err(msg, ##__VA_ARGS__);			\
238 	} while (0)
239 
240 #ifdef CONFIG_IP_VS_DEBUG
241 #define EnterFunction(level)						\
242 	do {								\
243 		if (level <= ip_vs_get_debug_level())			\
244 			printk(KERN_DEBUG				\
245 			       pr_fmt("Enter: %s, %s line %i\n"),	\
246 			       __func__, __FILE__, __LINE__);		\
247 	} while (0)
248 #define LeaveFunction(level)						\
249 	do {								\
250 		if (level <= ip_vs_get_debug_level())			\
251 			printk(KERN_DEBUG				\
252 			       pr_fmt("Leave: %s, %s line %i\n"),	\
253 			       __func__, __FILE__, __LINE__);		\
254 	} while (0)
255 #else
256 #define EnterFunction(level)   do {} while (0)
257 #define LeaveFunction(level)   do {} while (0)
258 #endif
259 
260 #define	IP_VS_WAIT_WHILE(expr)	while (expr) { cpu_relax(); }
261 
262 
263 /*
264  *      The port number of FTP service (in network order).
265  */
266 #define FTPPORT  cpu_to_be16(21)
267 #define FTPDATA  cpu_to_be16(20)
268 
269 /*
270  *      TCP State Values
271  */
272 enum {
273 	IP_VS_TCP_S_NONE = 0,
274 	IP_VS_TCP_S_ESTABLISHED,
275 	IP_VS_TCP_S_SYN_SENT,
276 	IP_VS_TCP_S_SYN_RECV,
277 	IP_VS_TCP_S_FIN_WAIT,
278 	IP_VS_TCP_S_TIME_WAIT,
279 	IP_VS_TCP_S_CLOSE,
280 	IP_VS_TCP_S_CLOSE_WAIT,
281 	IP_VS_TCP_S_LAST_ACK,
282 	IP_VS_TCP_S_LISTEN,
283 	IP_VS_TCP_S_SYNACK,
284 	IP_VS_TCP_S_LAST
285 };
286 
287 /*
288  *	UDP State Values
289  */
290 enum {
291 	IP_VS_UDP_S_NORMAL,
292 	IP_VS_UDP_S_LAST,
293 };
294 
295 /*
296  *	ICMP State Values
297  */
298 enum {
299 	IP_VS_ICMP_S_NORMAL,
300 	IP_VS_ICMP_S_LAST,
301 };
302 
303 /*
304  *	SCTP State Values
305  */
306 enum ip_vs_sctp_states {
307 	IP_VS_SCTP_S_NONE,
308 	IP_VS_SCTP_S_INIT_CLI,
309 	IP_VS_SCTP_S_INIT_SER,
310 	IP_VS_SCTP_S_INIT_ACK_CLI,
311 	IP_VS_SCTP_S_INIT_ACK_SER,
312 	IP_VS_SCTP_S_ECHO_CLI,
313 	IP_VS_SCTP_S_ECHO_SER,
314 	IP_VS_SCTP_S_ESTABLISHED,
315 	IP_VS_SCTP_S_SHUT_CLI,
316 	IP_VS_SCTP_S_SHUT_SER,
317 	IP_VS_SCTP_S_SHUT_ACK_CLI,
318 	IP_VS_SCTP_S_SHUT_ACK_SER,
319 	IP_VS_SCTP_S_CLOSED,
320 	IP_VS_SCTP_S_LAST
321 };
322 
323 /*
324  *	Delta sequence info structure
325  *	Each ip_vs_conn has 2 (output AND input seq. changes).
326  *      Only used in the VS/NAT.
327  */
328 struct ip_vs_seq {
329 	__u32			init_seq;	/* Add delta from this seq */
330 	__u32			delta;		/* Delta in sequence numbers */
331 	__u32			previous_delta;	/* Delta in sequence numbers
332 						   before last resized pkt */
333 };
334 
335 /*
336  * counters per cpu
337  */
338 struct ip_vs_counters {
339 	__u32		conns;		/* connections scheduled */
340 	__u32		inpkts;		/* incoming packets */
341 	__u32		outpkts;	/* outgoing packets */
342 	__u64		inbytes;	/* incoming bytes */
343 	__u64		outbytes;	/* outgoing bytes */
344 };
345 /*
346  * Stats per cpu
347  */
348 struct ip_vs_cpu_stats {
349 	struct ip_vs_counters   ustats;
350 	struct u64_stats_sync   syncp;
351 };
352 
353 /*
354  *	IPVS statistics objects
355  */
356 struct ip_vs_estimator {
357 	struct list_head	list;
358 
359 	u64			last_inbytes;
360 	u64			last_outbytes;
361 	u32			last_conns;
362 	u32			last_inpkts;
363 	u32			last_outpkts;
364 
365 	u32			cps;
366 	u32			inpps;
367 	u32			outpps;
368 	u32			inbps;
369 	u32			outbps;
370 };
371 
372 struct ip_vs_stats {
373 	struct ip_vs_stats_user	ustats;		/* statistics */
374 	struct ip_vs_estimator	est;		/* estimator */
375 	struct ip_vs_cpu_stats	*cpustats;	/* per cpu counters */
376 	spinlock_t		lock;		/* spin lock */
377 	struct ip_vs_stats_user	ustats0;	/* reset values */
378 };
379 
380 struct dst_entry;
381 struct iphdr;
382 struct ip_vs_conn;
383 struct ip_vs_app;
384 struct sk_buff;
385 struct ip_vs_proto_data;
386 
387 struct ip_vs_protocol {
388 	struct ip_vs_protocol	*next;
389 	char			*name;
390 	u16			protocol;
391 	u16			num_states;
392 	int			dont_defrag;
393 
394 	void (*init)(struct ip_vs_protocol *pp);
395 
396 	void (*exit)(struct ip_vs_protocol *pp);
397 
398 	void (*init_netns)(struct net *net, struct ip_vs_proto_data *pd);
399 
400 	void (*exit_netns)(struct net *net, struct ip_vs_proto_data *pd);
401 
402 	int (*conn_schedule)(int af, struct sk_buff *skb,
403 			     struct ip_vs_proto_data *pd,
404 			     int *verdict, struct ip_vs_conn **cpp);
405 
406 	struct ip_vs_conn *
407 	(*conn_in_get)(int af,
408 		       const struct sk_buff *skb,
409 		       const struct ip_vs_iphdr *iph,
410 		       unsigned int proto_off,
411 		       int inverse);
412 
413 	struct ip_vs_conn *
414 	(*conn_out_get)(int af,
415 			const struct sk_buff *skb,
416 			const struct ip_vs_iphdr *iph,
417 			unsigned int proto_off,
418 			int inverse);
419 
420 	int (*snat_handler)(struct sk_buff *skb,
421 			    struct ip_vs_protocol *pp, struct ip_vs_conn *cp);
422 
423 	int (*dnat_handler)(struct sk_buff *skb,
424 			    struct ip_vs_protocol *pp, struct ip_vs_conn *cp);
425 
426 	int (*csum_check)(int af, struct sk_buff *skb,
427 			  struct ip_vs_protocol *pp);
428 
429 	const char *(*state_name)(int state);
430 
431 	int (*state_transition)(struct ip_vs_conn *cp, int direction,
432 				const struct sk_buff *skb,
433 				struct ip_vs_proto_data *pd);
434 
435 	int (*register_app)(struct net *net, struct ip_vs_app *inc);
436 
437 	void (*unregister_app)(struct net *net, struct ip_vs_app *inc);
438 
439 	int (*app_conn_bind)(struct ip_vs_conn *cp);
440 
441 	void (*debug_packet)(int af, struct ip_vs_protocol *pp,
442 			     const struct sk_buff *skb,
443 			     int offset,
444 			     const char *msg);
445 
446 	void (*timeout_change)(struct ip_vs_proto_data *pd, int flags);
447 };
448 
449 /*
450  * protocol data per netns
451  */
452 struct ip_vs_proto_data {
453 	struct ip_vs_proto_data	*next;
454 	struct ip_vs_protocol	*pp;
455 	int			*timeout_table;	/* protocol timeout table */
456 	atomic_t		appcnt;		/* counter of proto app incs. */
457 	struct tcp_states_t	*tcp_state_table;
458 };
459 
460 extern struct ip_vs_protocol   *ip_vs_proto_get(unsigned short proto);
461 extern struct ip_vs_proto_data *ip_vs_proto_data_get(struct net *net,
462 						     unsigned short proto);
463 
464 struct ip_vs_conn_param {
465 	struct net			*net;
466 	const union nf_inet_addr	*caddr;
467 	const union nf_inet_addr	*vaddr;
468 	__be16				cport;
469 	__be16				vport;
470 	__u16				protocol;
471 	u16				af;
472 
473 	const struct ip_vs_pe		*pe;
474 	char				*pe_data;
475 	__u8				pe_data_len;
476 };
477 
478 /*
479  *	IP_VS structure allocated for each dynamically scheduled connection
480  */
481 struct ip_vs_conn {
482 	struct hlist_node	c_list;         /* hashed list heads */
483 #ifdef CONFIG_NET_NS
484 	struct net              *net;           /* Name space */
485 #endif
486 	/* Protocol, addresses and port numbers */
487 	u16                     af;             /* address family */
488 	__be16                  cport;
489 	__be16                  vport;
490 	__be16                  dport;
491 	__u32                   fwmark;         /* Fire wall mark from skb */
492 	union nf_inet_addr      caddr;          /* client address */
493 	union nf_inet_addr      vaddr;          /* virtual address */
494 	union nf_inet_addr      daddr;          /* destination address */
495 	volatile __u32          flags;          /* status flags */
496 	__u16                   protocol;       /* Which protocol (TCP/UDP) */
497 
498 	/* counter and timer */
499 	atomic_t		refcnt;		/* reference count */
500 	struct timer_list	timer;		/* Expiration timer */
501 	volatile unsigned long	timeout;	/* timeout */
502 
503 	/* Flags and state transition */
504 	spinlock_t              lock;           /* lock for state transition */
505 	volatile __u16          state;          /* state info */
506 	volatile __u16          old_state;      /* old state, to be used for
507 						 * state transition triggerd
508 						 * synchronization
509 						 */
510 
511 	/* Control members */
512 	struct ip_vs_conn       *control;       /* Master control connection */
513 	atomic_t                n_control;      /* Number of controlled ones */
514 	struct ip_vs_dest       *dest;          /* real server */
515 	atomic_t                in_pkts;        /* incoming packet counter */
516 
517 	/* packet transmitter for different forwarding methods.  If it
518 	   mangles the packet, it must return NF_DROP or better NF_STOLEN,
519 	   otherwise this must be changed to a sk_buff **.
520 	   NF_ACCEPT can be returned when destination is local.
521 	 */
522 	int (*packet_xmit)(struct sk_buff *skb, struct ip_vs_conn *cp,
523 			   struct ip_vs_protocol *pp);
524 
525 	/* Note: we can group the following members into a structure,
526 	   in order to save more space, and the following members are
527 	   only used in VS/NAT anyway */
528 	struct ip_vs_app        *app;           /* bound ip_vs_app object */
529 	void                    *app_data;      /* Application private data */
530 	struct ip_vs_seq        in_seq;         /* incoming seq. struct */
531 	struct ip_vs_seq        out_seq;        /* outgoing seq. struct */
532 
533 	const struct ip_vs_pe	*pe;
534 	char			*pe_data;
535 	__u8			pe_data_len;
536 };
537 
538 /*
539  *  To save some memory in conn table when name space is disabled.
540  */
541 static inline struct net *ip_vs_conn_net(const struct ip_vs_conn *cp)
542 {
543 #ifdef CONFIG_NET_NS
544 	return cp->net;
545 #else
546 	return &init_net;
547 #endif
548 }
549 static inline void ip_vs_conn_net_set(struct ip_vs_conn *cp, struct net *net)
550 {
551 #ifdef CONFIG_NET_NS
552 	cp->net = net;
553 #endif
554 }
555 
556 static inline int ip_vs_conn_net_eq(const struct ip_vs_conn *cp,
557 				    struct net *net)
558 {
559 #ifdef CONFIG_NET_NS
560 	return cp->net == net;
561 #else
562 	return 1;
563 #endif
564 }
565 
566 /*
567  *	Extended internal versions of struct ip_vs_service_user and
568  *	ip_vs_dest_user for IPv6 support.
569  *
570  *	We need these to conveniently pass around service and destination
571  *	options, but unfortunately, we also need to keep the old definitions to
572  *	maintain userspace backwards compatibility for the setsockopt interface.
573  */
574 struct ip_vs_service_user_kern {
575 	/* virtual service addresses */
576 	u16			af;
577 	u16			protocol;
578 	union nf_inet_addr	addr;		/* virtual ip address */
579 	u16			port;
580 	u32			fwmark;		/* firwall mark of service */
581 
582 	/* virtual service options */
583 	char			*sched_name;
584 	char			*pe_name;
585 	unsigned		flags;		/* virtual service flags */
586 	unsigned		timeout;	/* persistent timeout in sec */
587 	u32			netmask;	/* persistent netmask */
588 };
589 
590 
591 struct ip_vs_dest_user_kern {
592 	/* destination server address */
593 	union nf_inet_addr	addr;
594 	u16			port;
595 
596 	/* real server options */
597 	unsigned		conn_flags;	/* connection flags */
598 	int			weight;		/* destination weight */
599 
600 	/* thresholds for active connections */
601 	u32			u_threshold;	/* upper threshold */
602 	u32			l_threshold;	/* lower threshold */
603 };
604 
605 
606 /*
607  *	The information about the virtual service offered to the net
608  *	and the forwarding entries
609  */
610 struct ip_vs_service {
611 	struct list_head	s_list;   /* for normal service table */
612 	struct list_head	f_list;   /* for fwmark-based service table */
613 	atomic_t		refcnt;   /* reference counter */
614 	atomic_t		usecnt;   /* use counter */
615 
616 	u16			af;       /* address family */
617 	__u16			protocol; /* which protocol (TCP/UDP) */
618 	union nf_inet_addr	addr;	  /* IP address for virtual service */
619 	__be16			port;	  /* port number for the service */
620 	__u32                   fwmark;   /* firewall mark of the service */
621 	unsigned		flags;	  /* service status flags */
622 	unsigned		timeout;  /* persistent timeout in ticks */
623 	__be32			netmask;  /* grouping granularity */
624 	struct net		*net;
625 
626 	struct list_head	destinations;  /* real server d-linked list */
627 	__u32			num_dests;     /* number of servers */
628 	struct ip_vs_stats      stats;         /* statistics for the service */
629 	struct ip_vs_app	*inc;	  /* bind conns to this app inc */
630 
631 	/* for scheduling */
632 	struct ip_vs_scheduler	*scheduler;    /* bound scheduler object */
633 	rwlock_t		sched_lock;    /* lock sched_data */
634 	void			*sched_data;   /* scheduler application data */
635 
636 	/* alternate persistence engine */
637 	struct ip_vs_pe		*pe;
638 };
639 
640 
641 /*
642  *	The real server destination forwarding entry
643  *	with ip address, port number, and so on.
644  */
645 struct ip_vs_dest {
646 	struct list_head	n_list;   /* for the dests in the service */
647 	struct list_head	d_list;   /* for table with all the dests */
648 
649 	u16			af;		/* address family */
650 	__be16			port;		/* port number of the server */
651 	union nf_inet_addr	addr;		/* IP address of the server */
652 	volatile unsigned	flags;		/* dest status flags */
653 	atomic_t		conn_flags;	/* flags to copy to conn */
654 	atomic_t		weight;		/* server weight */
655 
656 	atomic_t		refcnt;		/* reference counter */
657 	struct ip_vs_stats      stats;          /* statistics */
658 
659 	/* connection counters and thresholds */
660 	atomic_t		activeconns;	/* active connections */
661 	atomic_t		inactconns;	/* inactive connections */
662 	atomic_t		persistconns;	/* persistent connections */
663 	__u32			u_threshold;	/* upper threshold */
664 	__u32			l_threshold;	/* lower threshold */
665 
666 	/* for destination cache */
667 	spinlock_t		dst_lock;	/* lock of dst_cache */
668 	struct dst_entry	*dst_cache;	/* destination cache entry */
669 	u32			dst_rtos;	/* RT_TOS(tos) for dst */
670 	u32			dst_cookie;
671 #ifdef CONFIG_IP_VS_IPV6
672 	struct in6_addr		dst_saddr;
673 #endif
674 
675 	/* for virtual service */
676 	struct ip_vs_service	*svc;		/* service it belongs to */
677 	__u16			protocol;	/* which protocol (TCP/UDP) */
678 	__be16			vport;		/* virtual port number */
679 	union nf_inet_addr	vaddr;		/* virtual IP address */
680 	__u32			vfwmark;	/* firewall mark of service */
681 };
682 
683 
684 /*
685  *	The scheduler object
686  */
687 struct ip_vs_scheduler {
688 	struct list_head	n_list;		/* d-linked list head */
689 	char			*name;		/* scheduler name */
690 	atomic_t		refcnt;		/* reference counter */
691 	struct module		*module;	/* THIS_MODULE/NULL */
692 
693 	/* scheduler initializing service */
694 	int (*init_service)(struct ip_vs_service *svc);
695 	/* scheduling service finish */
696 	int (*done_service)(struct ip_vs_service *svc);
697 	/* scheduler updating service */
698 	int (*update_service)(struct ip_vs_service *svc);
699 
700 	/* selecting a server from the given service */
701 	struct ip_vs_dest* (*schedule)(struct ip_vs_service *svc,
702 				       const struct sk_buff *skb);
703 };
704 
705 /* The persistence engine object */
706 struct ip_vs_pe {
707 	struct list_head	n_list;		/* d-linked list head */
708 	char			*name;		/* scheduler name */
709 	atomic_t		refcnt;		/* reference counter */
710 	struct module		*module;	/* THIS_MODULE/NULL */
711 
712 	/* get the connection template, if any */
713 	int (*fill_param)(struct ip_vs_conn_param *p, struct sk_buff *skb);
714 	bool (*ct_match)(const struct ip_vs_conn_param *p,
715 			 struct ip_vs_conn *ct);
716 	u32 (*hashkey_raw)(const struct ip_vs_conn_param *p, u32 initval,
717 			   bool inverse);
718 	int (*show_pe_data)(const struct ip_vs_conn *cp, char *buf);
719 };
720 
721 /*
722  *	The application module object (a.k.a. app incarnation)
723  */
724 struct ip_vs_app {
725 	struct list_head	a_list;		/* member in app list */
726 	int			type;		/* IP_VS_APP_TYPE_xxx */
727 	char			*name;		/* application module name */
728 	__u16			protocol;
729 	struct module		*module;	/* THIS_MODULE/NULL */
730 	struct list_head	incs_list;	/* list of incarnations */
731 
732 	/* members for application incarnations */
733 	struct list_head	p_list;		/* member in proto app list */
734 	struct ip_vs_app	*app;		/* its real application */
735 	__be16			port;		/* port number in net order */
736 	atomic_t		usecnt;		/* usage counter */
737 
738 	/*
739 	 * output hook: Process packet in inout direction, diff set for TCP.
740 	 * Return: 0=Error, 1=Payload Not Mangled/Mangled but checksum is ok,
741 	 *	   2=Mangled but checksum was not updated
742 	 */
743 	int (*pkt_out)(struct ip_vs_app *, struct ip_vs_conn *,
744 		       struct sk_buff *, int *diff);
745 
746 	/*
747 	 * input hook: Process packet in outin direction, diff set for TCP.
748 	 * Return: 0=Error, 1=Payload Not Mangled/Mangled but checksum is ok,
749 	 *	   2=Mangled but checksum was not updated
750 	 */
751 	int (*pkt_in)(struct ip_vs_app *, struct ip_vs_conn *,
752 		      struct sk_buff *, int *diff);
753 
754 	/* ip_vs_app initializer */
755 	int (*init_conn)(struct ip_vs_app *, struct ip_vs_conn *);
756 
757 	/* ip_vs_app finish */
758 	int (*done_conn)(struct ip_vs_app *, struct ip_vs_conn *);
759 
760 
761 	/* not used now */
762 	int (*bind_conn)(struct ip_vs_app *, struct ip_vs_conn *,
763 			 struct ip_vs_protocol *);
764 
765 	void (*unbind_conn)(struct ip_vs_app *, struct ip_vs_conn *);
766 
767 	int *			timeout_table;
768 	int *			timeouts;
769 	int			timeouts_size;
770 
771 	int (*conn_schedule)(struct sk_buff *skb, struct ip_vs_app *app,
772 			     int *verdict, struct ip_vs_conn **cpp);
773 
774 	struct ip_vs_conn *
775 	(*conn_in_get)(const struct sk_buff *skb, struct ip_vs_app *app,
776 		       const struct iphdr *iph, unsigned int proto_off,
777 		       int inverse);
778 
779 	struct ip_vs_conn *
780 	(*conn_out_get)(const struct sk_buff *skb, struct ip_vs_app *app,
781 			const struct iphdr *iph, unsigned int proto_off,
782 			int inverse);
783 
784 	int (*state_transition)(struct ip_vs_conn *cp, int direction,
785 				const struct sk_buff *skb,
786 				struct ip_vs_app *app);
787 
788 	void (*timeout_change)(struct ip_vs_app *app, int flags);
789 };
790 
791 /* IPVS in network namespace */
792 struct netns_ipvs {
793 	int			gen;		/* Generation */
794 	/*
795 	 *	Hash table: for real service lookups
796 	 */
797 	#define IP_VS_RTAB_BITS 4
798 	#define IP_VS_RTAB_SIZE (1 << IP_VS_RTAB_BITS)
799 	#define IP_VS_RTAB_MASK (IP_VS_RTAB_SIZE - 1)
800 
801 	struct list_head	rs_table[IP_VS_RTAB_SIZE];
802 	/* ip_vs_app */
803 	struct list_head	app_list;
804 	struct mutex		app_mutex;
805 	struct lock_class_key	app_key;	/* mutex debuging */
806 
807 	/* ip_vs_proto */
808 	#define IP_VS_PROTO_TAB_SIZE	32	/* must be power of 2 */
809 	struct ip_vs_proto_data *proto_data_table[IP_VS_PROTO_TAB_SIZE];
810 	/* ip_vs_proto_tcp */
811 #ifdef CONFIG_IP_VS_PROTO_TCP
812 	#define	TCP_APP_TAB_BITS	4
813 	#define	TCP_APP_TAB_SIZE	(1 << TCP_APP_TAB_BITS)
814 	#define	TCP_APP_TAB_MASK	(TCP_APP_TAB_SIZE - 1)
815 	struct list_head	tcp_apps[TCP_APP_TAB_SIZE];
816 	spinlock_t		tcp_app_lock;
817 #endif
818 	/* ip_vs_proto_udp */
819 #ifdef CONFIG_IP_VS_PROTO_UDP
820 	#define	UDP_APP_TAB_BITS	4
821 	#define	UDP_APP_TAB_SIZE	(1 << UDP_APP_TAB_BITS)
822 	#define	UDP_APP_TAB_MASK	(UDP_APP_TAB_SIZE - 1)
823 	struct list_head	udp_apps[UDP_APP_TAB_SIZE];
824 	spinlock_t		udp_app_lock;
825 #endif
826 	/* ip_vs_proto_sctp */
827 #ifdef CONFIG_IP_VS_PROTO_SCTP
828 	#define SCTP_APP_TAB_BITS	4
829 	#define SCTP_APP_TAB_SIZE	(1 << SCTP_APP_TAB_BITS)
830 	#define SCTP_APP_TAB_MASK	(SCTP_APP_TAB_SIZE - 1)
831 	/* Hash table for SCTP application incarnations	 */
832 	struct list_head	sctp_apps[SCTP_APP_TAB_SIZE];
833 	spinlock_t		sctp_app_lock;
834 #endif
835 	/* ip_vs_conn */
836 	atomic_t		conn_count;      /*  connection counter */
837 
838 	/* ip_vs_ctl */
839 	struct ip_vs_stats		tot_stats;  /* Statistics & est. */
840 
841 	int			num_services;    /* no of virtual services */
842 
843 	rwlock_t		rs_lock;         /* real services table */
844 	/* semaphore for IPVS sockopts. And, [gs]etsockopt may sleep. */
845 	struct lock_class_key	ctl_key;	/* ctl_mutex debuging */
846 	/* Trash for destinations */
847 	struct list_head	dest_trash;
848 	/* Service counters */
849 	atomic_t		ftpsvc_counter;
850 	atomic_t		nullsvc_counter;
851 
852 #ifdef CONFIG_SYSCTL
853 	/* 1/rate drop and drop-entry variables */
854 	struct delayed_work	defense_work;   /* Work handler */
855 	int			drop_rate;
856 	int			drop_counter;
857 	atomic_t		dropentry;
858 	/* locks in ctl.c */
859 	spinlock_t		dropentry_lock;  /* drop entry handling */
860 	spinlock_t		droppacket_lock; /* drop packet handling */
861 	spinlock_t		securetcp_lock;  /* state and timeout tables */
862 
863 	/* sys-ctl struct */
864 	struct ctl_table_header	*sysctl_hdr;
865 	struct ctl_table	*sysctl_tbl;
866 #endif
867 
868 	/* sysctl variables */
869 	int			sysctl_amemthresh;
870 	int			sysctl_am_droprate;
871 	int			sysctl_drop_entry;
872 	int			sysctl_drop_packet;
873 	int			sysctl_secure_tcp;
874 #ifdef CONFIG_IP_VS_NFCT
875 	int			sysctl_conntrack;
876 #endif
877 	int			sysctl_snat_reroute;
878 	int			sysctl_sync_ver;
879 	int			sysctl_cache_bypass;
880 	int			sysctl_expire_nodest_conn;
881 	int			sysctl_expire_quiescent_template;
882 	int			sysctl_sync_threshold[2];
883 	int			sysctl_nat_icmp_send;
884 
885 	/* ip_vs_lblc */
886 	int			sysctl_lblc_expiration;
887 	struct ctl_table_header	*lblc_ctl_header;
888 	struct ctl_table	*lblc_ctl_table;
889 	/* ip_vs_lblcr */
890 	int			sysctl_lblcr_expiration;
891 	struct ctl_table_header	*lblcr_ctl_header;
892 	struct ctl_table	*lblcr_ctl_table;
893 	/* ip_vs_est */
894 	struct list_head	est_list;	/* estimator list */
895 	spinlock_t		est_lock;
896 	struct timer_list	est_timer;	/* Estimation timer */
897 	/* ip_vs_sync */
898 	struct list_head	sync_queue;
899 	spinlock_t		sync_lock;
900 	struct ip_vs_sync_buff  *sync_buff;
901 	spinlock_t		sync_buff_lock;
902 	struct sockaddr_in	sync_mcast_addr;
903 	struct task_struct	*master_thread;
904 	struct task_struct	*backup_thread;
905 	int			send_mesg_maxlen;
906 	int			recv_mesg_maxlen;
907 	volatile int		sync_state;
908 	volatile int		master_syncid;
909 	volatile int		backup_syncid;
910 	/* multicast interface name */
911 	char			master_mcast_ifn[IP_VS_IFNAME_MAXLEN];
912 	char			backup_mcast_ifn[IP_VS_IFNAME_MAXLEN];
913 	/* net name space ptr */
914 	struct net		*net;            /* Needed by timer routines */
915 };
916 
917 #define DEFAULT_SYNC_THRESHOLD	3
918 #define DEFAULT_SYNC_PERIOD	50
919 #define DEFAULT_SYNC_VER	1
920 
921 #ifdef CONFIG_SYSCTL
922 
923 static inline int sysctl_sync_threshold(struct netns_ipvs *ipvs)
924 {
925 	return ipvs->sysctl_sync_threshold[0];
926 }
927 
928 static inline int sysctl_sync_period(struct netns_ipvs *ipvs)
929 {
930 	return ipvs->sysctl_sync_threshold[1];
931 }
932 
933 static inline int sysctl_sync_ver(struct netns_ipvs *ipvs)
934 {
935 	return ipvs->sysctl_sync_ver;
936 }
937 
938 #else
939 
940 static inline int sysctl_sync_threshold(struct netns_ipvs *ipvs)
941 {
942 	return DEFAULT_SYNC_THRESHOLD;
943 }
944 
945 static inline int sysctl_sync_period(struct netns_ipvs *ipvs)
946 {
947 	return DEFAULT_SYNC_PERIOD;
948 }
949 
950 static inline int sysctl_sync_ver(struct netns_ipvs *ipvs)
951 {
952 	return DEFAULT_SYNC_VER;
953 }
954 
955 #endif
956 
957 /*
958  *      IPVS core functions
959  *      (from ip_vs_core.c)
960  */
961 extern const char *ip_vs_proto_name(unsigned proto);
962 extern void ip_vs_init_hash_table(struct list_head *table, int rows);
963 #define IP_VS_INIT_HASH_TABLE(t) ip_vs_init_hash_table((t), ARRAY_SIZE((t)))
964 
965 #define IP_VS_APP_TYPE_FTP	1
966 
967 /*
968  *     ip_vs_conn handling functions
969  *     (from ip_vs_conn.c)
970  */
971 
972 enum {
973 	IP_VS_DIR_INPUT = 0,
974 	IP_VS_DIR_OUTPUT,
975 	IP_VS_DIR_INPUT_ONLY,
976 	IP_VS_DIR_LAST,
977 };
978 
979 static inline void ip_vs_conn_fill_param(struct net *net, int af, int protocol,
980 					 const union nf_inet_addr *caddr,
981 					 __be16 cport,
982 					 const union nf_inet_addr *vaddr,
983 					 __be16 vport,
984 					 struct ip_vs_conn_param *p)
985 {
986 	p->net = net;
987 	p->af = af;
988 	p->protocol = protocol;
989 	p->caddr = caddr;
990 	p->cport = cport;
991 	p->vaddr = vaddr;
992 	p->vport = vport;
993 	p->pe = NULL;
994 	p->pe_data = NULL;
995 }
996 
997 struct ip_vs_conn *ip_vs_conn_in_get(const struct ip_vs_conn_param *p);
998 struct ip_vs_conn *ip_vs_ct_in_get(const struct ip_vs_conn_param *p);
999 
1000 struct ip_vs_conn * ip_vs_conn_in_get_proto(int af, const struct sk_buff *skb,
1001 					    const struct ip_vs_iphdr *iph,
1002 					    unsigned int proto_off,
1003 					    int inverse);
1004 
1005 struct ip_vs_conn *ip_vs_conn_out_get(const struct ip_vs_conn_param *p);
1006 
1007 struct ip_vs_conn * ip_vs_conn_out_get_proto(int af, const struct sk_buff *skb,
1008 					     const struct ip_vs_iphdr *iph,
1009 					     unsigned int proto_off,
1010 					     int inverse);
1011 
1012 /* put back the conn without restarting its timer */
1013 static inline void __ip_vs_conn_put(struct ip_vs_conn *cp)
1014 {
1015 	atomic_dec(&cp->refcnt);
1016 }
1017 extern void ip_vs_conn_put(struct ip_vs_conn *cp);
1018 extern void ip_vs_conn_fill_cport(struct ip_vs_conn *cp, __be16 cport);
1019 
1020 struct ip_vs_conn *ip_vs_conn_new(const struct ip_vs_conn_param *p,
1021 				  const union nf_inet_addr *daddr,
1022 				  __be16 dport, unsigned flags,
1023 				  struct ip_vs_dest *dest, __u32 fwmark);
1024 extern void ip_vs_conn_expire_now(struct ip_vs_conn *cp);
1025 
1026 extern const char * ip_vs_state_name(__u16 proto, int state);
1027 
1028 extern void ip_vs_tcp_conn_listen(struct net *net, struct ip_vs_conn *cp);
1029 extern int ip_vs_check_template(struct ip_vs_conn *ct);
1030 extern void ip_vs_random_dropentry(struct net *net);
1031 extern int ip_vs_conn_init(void);
1032 extern void ip_vs_conn_cleanup(void);
1033 
1034 static inline void ip_vs_control_del(struct ip_vs_conn *cp)
1035 {
1036 	struct ip_vs_conn *ctl_cp = cp->control;
1037 	if (!ctl_cp) {
1038 		IP_VS_ERR_BUF("request control DEL for uncontrolled: "
1039 			      "%s:%d to %s:%d\n",
1040 			      IP_VS_DBG_ADDR(cp->af, &cp->caddr),
1041 			      ntohs(cp->cport),
1042 			      IP_VS_DBG_ADDR(cp->af, &cp->vaddr),
1043 			      ntohs(cp->vport));
1044 
1045 		return;
1046 	}
1047 
1048 	IP_VS_DBG_BUF(7, "DELeting control for: "
1049 		      "cp.dst=%s:%d ctl_cp.dst=%s:%d\n",
1050 		      IP_VS_DBG_ADDR(cp->af, &cp->caddr),
1051 		      ntohs(cp->cport),
1052 		      IP_VS_DBG_ADDR(cp->af, &ctl_cp->caddr),
1053 		      ntohs(ctl_cp->cport));
1054 
1055 	cp->control = NULL;
1056 	if (atomic_read(&ctl_cp->n_control) == 0) {
1057 		IP_VS_ERR_BUF("BUG control DEL with n=0 : "
1058 			      "%s:%d to %s:%d\n",
1059 			      IP_VS_DBG_ADDR(cp->af, &cp->caddr),
1060 			      ntohs(cp->cport),
1061 			      IP_VS_DBG_ADDR(cp->af, &cp->vaddr),
1062 			      ntohs(cp->vport));
1063 
1064 		return;
1065 	}
1066 	atomic_dec(&ctl_cp->n_control);
1067 }
1068 
1069 static inline void
1070 ip_vs_control_add(struct ip_vs_conn *cp, struct ip_vs_conn *ctl_cp)
1071 {
1072 	if (cp->control) {
1073 		IP_VS_ERR_BUF("request control ADD for already controlled: "
1074 			      "%s:%d to %s:%d\n",
1075 			      IP_VS_DBG_ADDR(cp->af, &cp->caddr),
1076 			      ntohs(cp->cport),
1077 			      IP_VS_DBG_ADDR(cp->af, &cp->vaddr),
1078 			      ntohs(cp->vport));
1079 
1080 		ip_vs_control_del(cp);
1081 	}
1082 
1083 	IP_VS_DBG_BUF(7, "ADDing control for: "
1084 		      "cp.dst=%s:%d ctl_cp.dst=%s:%d\n",
1085 		      IP_VS_DBG_ADDR(cp->af, &cp->caddr),
1086 		      ntohs(cp->cport),
1087 		      IP_VS_DBG_ADDR(cp->af, &ctl_cp->caddr),
1088 		      ntohs(ctl_cp->cport));
1089 
1090 	cp->control = ctl_cp;
1091 	atomic_inc(&ctl_cp->n_control);
1092 }
1093 
1094 
1095 /*
1096  *      IPVS application functions
1097  *      (from ip_vs_app.c)
1098  */
1099 #define IP_VS_APP_MAX_PORTS  8
1100 extern int register_ip_vs_app(struct net *net, struct ip_vs_app *app);
1101 extern void unregister_ip_vs_app(struct net *net, struct ip_vs_app *app);
1102 extern int ip_vs_bind_app(struct ip_vs_conn *cp, struct ip_vs_protocol *pp);
1103 extern void ip_vs_unbind_app(struct ip_vs_conn *cp);
1104 extern int register_ip_vs_app_inc(struct net *net, struct ip_vs_app *app,
1105 				  __u16 proto, __u16 port);
1106 extern int ip_vs_app_inc_get(struct ip_vs_app *inc);
1107 extern void ip_vs_app_inc_put(struct ip_vs_app *inc);
1108 
1109 extern int ip_vs_app_pkt_out(struct ip_vs_conn *, struct sk_buff *skb);
1110 extern int ip_vs_app_pkt_in(struct ip_vs_conn *, struct sk_buff *skb);
1111 extern int ip_vs_app_init(void);
1112 extern void ip_vs_app_cleanup(void);
1113 
1114 void ip_vs_bind_pe(struct ip_vs_service *svc, struct ip_vs_pe *pe);
1115 void ip_vs_unbind_pe(struct ip_vs_service *svc);
1116 int register_ip_vs_pe(struct ip_vs_pe *pe);
1117 int unregister_ip_vs_pe(struct ip_vs_pe *pe);
1118 struct ip_vs_pe *ip_vs_pe_getbyname(const char *name);
1119 struct ip_vs_pe *__ip_vs_pe_getbyname(const char *pe_name);
1120 
1121 static inline void ip_vs_pe_get(const struct ip_vs_pe *pe)
1122 {
1123 	if (pe && pe->module)
1124 		__module_get(pe->module);
1125 }
1126 
1127 static inline void ip_vs_pe_put(const struct ip_vs_pe *pe)
1128 {
1129 	if (pe && pe->module)
1130 		module_put(pe->module);
1131 }
1132 
1133 /*
1134  *	IPVS protocol functions (from ip_vs_proto.c)
1135  */
1136 extern int ip_vs_protocol_init(void);
1137 extern void ip_vs_protocol_cleanup(void);
1138 extern void ip_vs_protocol_timeout_change(struct netns_ipvs *ipvs, int flags);
1139 extern int *ip_vs_create_timeout_table(int *table, int size);
1140 extern int
1141 ip_vs_set_state_timeout(int *table, int num, const char *const *names,
1142 			const char *name, int to);
1143 extern void
1144 ip_vs_tcpudp_debug_packet(int af, struct ip_vs_protocol *pp,
1145 			  const struct sk_buff *skb,
1146 			  int offset, const char *msg);
1147 
1148 extern struct ip_vs_protocol ip_vs_protocol_tcp;
1149 extern struct ip_vs_protocol ip_vs_protocol_udp;
1150 extern struct ip_vs_protocol ip_vs_protocol_icmp;
1151 extern struct ip_vs_protocol ip_vs_protocol_esp;
1152 extern struct ip_vs_protocol ip_vs_protocol_ah;
1153 extern struct ip_vs_protocol ip_vs_protocol_sctp;
1154 
1155 /*
1156  *      Registering/unregistering scheduler functions
1157  *      (from ip_vs_sched.c)
1158  */
1159 extern int register_ip_vs_scheduler(struct ip_vs_scheduler *scheduler);
1160 extern int unregister_ip_vs_scheduler(struct ip_vs_scheduler *scheduler);
1161 extern int ip_vs_bind_scheduler(struct ip_vs_service *svc,
1162 				struct ip_vs_scheduler *scheduler);
1163 extern int ip_vs_unbind_scheduler(struct ip_vs_service *svc);
1164 extern struct ip_vs_scheduler *ip_vs_scheduler_get(const char *sched_name);
1165 extern void ip_vs_scheduler_put(struct ip_vs_scheduler *scheduler);
1166 extern struct ip_vs_conn *
1167 ip_vs_schedule(struct ip_vs_service *svc, struct sk_buff *skb,
1168 	       struct ip_vs_proto_data *pd, int *ignored);
1169 extern int ip_vs_leave(struct ip_vs_service *svc, struct sk_buff *skb,
1170 			struct ip_vs_proto_data *pd);
1171 
1172 extern void ip_vs_scheduler_err(struct ip_vs_service *svc, const char *msg);
1173 
1174 
1175 /*
1176  *      IPVS control data and functions (from ip_vs_ctl.c)
1177  */
1178 extern struct ip_vs_stats ip_vs_stats;
1179 extern const struct ctl_path net_vs_ctl_path[];
1180 extern int sysctl_ip_vs_sync_ver;
1181 
1182 extern void ip_vs_sync_switch_mode(struct net *net, int mode);
1183 extern struct ip_vs_service *
1184 ip_vs_service_get(struct net *net, int af, __u32 fwmark, __u16 protocol,
1185 		  const union nf_inet_addr *vaddr, __be16 vport);
1186 
1187 static inline void ip_vs_service_put(struct ip_vs_service *svc)
1188 {
1189 	atomic_dec(&svc->usecnt);
1190 }
1191 
1192 extern struct ip_vs_dest *
1193 ip_vs_lookup_real_service(struct net *net, int af, __u16 protocol,
1194 			  const union nf_inet_addr *daddr, __be16 dport);
1195 
1196 extern int ip_vs_use_count_inc(void);
1197 extern void ip_vs_use_count_dec(void);
1198 extern int ip_vs_control_init(void);
1199 extern void ip_vs_control_cleanup(void);
1200 extern struct ip_vs_dest *
1201 ip_vs_find_dest(struct net *net, int af, const union nf_inet_addr *daddr,
1202 		__be16 dport, const union nf_inet_addr *vaddr, __be16 vport,
1203 		__u16 protocol, __u32 fwmark);
1204 extern struct ip_vs_dest *ip_vs_try_bind_dest(struct ip_vs_conn *cp);
1205 
1206 
1207 /*
1208  *      IPVS sync daemon data and function prototypes
1209  *      (from ip_vs_sync.c)
1210  */
1211 extern int start_sync_thread(struct net *net, int state, char *mcast_ifn,
1212 			     __u8 syncid);
1213 extern int stop_sync_thread(struct net *net, int state);
1214 extern void ip_vs_sync_conn(struct net *net, struct ip_vs_conn *cp);
1215 extern int ip_vs_sync_init(void);
1216 extern void ip_vs_sync_cleanup(void);
1217 
1218 
1219 /*
1220  *      IPVS rate estimator prototypes (from ip_vs_est.c)
1221  */
1222 extern int ip_vs_estimator_init(void);
1223 extern void ip_vs_estimator_cleanup(void);
1224 extern void ip_vs_start_estimator(struct net *net, struct ip_vs_stats *stats);
1225 extern void ip_vs_stop_estimator(struct net *net, struct ip_vs_stats *stats);
1226 extern void ip_vs_zero_estimator(struct ip_vs_stats *stats);
1227 extern void ip_vs_read_estimator(struct ip_vs_stats_user *dst,
1228 				 struct ip_vs_stats *stats);
1229 
1230 /*
1231  *	Various IPVS packet transmitters (from ip_vs_xmit.c)
1232  */
1233 extern int ip_vs_null_xmit
1234 (struct sk_buff *skb, struct ip_vs_conn *cp, struct ip_vs_protocol *pp);
1235 extern int ip_vs_bypass_xmit
1236 (struct sk_buff *skb, struct ip_vs_conn *cp, struct ip_vs_protocol *pp);
1237 extern int ip_vs_nat_xmit
1238 (struct sk_buff *skb, struct ip_vs_conn *cp, struct ip_vs_protocol *pp);
1239 extern int ip_vs_tunnel_xmit
1240 (struct sk_buff *skb, struct ip_vs_conn *cp, struct ip_vs_protocol *pp);
1241 extern int ip_vs_dr_xmit
1242 (struct sk_buff *skb, struct ip_vs_conn *cp, struct ip_vs_protocol *pp);
1243 extern int ip_vs_icmp_xmit
1244 (struct sk_buff *skb, struct ip_vs_conn *cp, struct ip_vs_protocol *pp, int offset);
1245 extern void ip_vs_dst_reset(struct ip_vs_dest *dest);
1246 
1247 #ifdef CONFIG_IP_VS_IPV6
1248 extern int ip_vs_bypass_xmit_v6
1249 (struct sk_buff *skb, struct ip_vs_conn *cp, struct ip_vs_protocol *pp);
1250 extern int ip_vs_nat_xmit_v6
1251 (struct sk_buff *skb, struct ip_vs_conn *cp, struct ip_vs_protocol *pp);
1252 extern int ip_vs_tunnel_xmit_v6
1253 (struct sk_buff *skb, struct ip_vs_conn *cp, struct ip_vs_protocol *pp);
1254 extern int ip_vs_dr_xmit_v6
1255 (struct sk_buff *skb, struct ip_vs_conn *cp, struct ip_vs_protocol *pp);
1256 extern int ip_vs_icmp_xmit_v6
1257 (struct sk_buff *skb, struct ip_vs_conn *cp, struct ip_vs_protocol *pp,
1258  int offset);
1259 #endif
1260 
1261 #ifdef CONFIG_SYSCTL
1262 /*
1263  *	This is a simple mechanism to ignore packets when
1264  *	we are loaded. Just set ip_vs_drop_rate to 'n' and
1265  *	we start to drop 1/rate of the packets
1266  */
1267 
1268 static inline int ip_vs_todrop(struct netns_ipvs *ipvs)
1269 {
1270 	if (!ipvs->drop_rate)
1271 		return 0;
1272 	if (--ipvs->drop_counter > 0)
1273 		return 0;
1274 	ipvs->drop_counter = ipvs->drop_rate;
1275 	return 1;
1276 }
1277 #else
1278 static inline int ip_vs_todrop(struct netns_ipvs *ipvs) { return 0; }
1279 #endif
1280 
1281 /*
1282  *      ip_vs_fwd_tag returns the forwarding tag of the connection
1283  */
1284 #define IP_VS_FWD_METHOD(cp)  (cp->flags & IP_VS_CONN_F_FWD_MASK)
1285 
1286 static inline char ip_vs_fwd_tag(struct ip_vs_conn *cp)
1287 {
1288 	char fwd;
1289 
1290 	switch (IP_VS_FWD_METHOD(cp)) {
1291 	case IP_VS_CONN_F_MASQ:
1292 		fwd = 'M'; break;
1293 	case IP_VS_CONN_F_LOCALNODE:
1294 		fwd = 'L'; break;
1295 	case IP_VS_CONN_F_TUNNEL:
1296 		fwd = 'T'; break;
1297 	case IP_VS_CONN_F_DROUTE:
1298 		fwd = 'R'; break;
1299 	case IP_VS_CONN_F_BYPASS:
1300 		fwd = 'B'; break;
1301 	default:
1302 		fwd = '?'; break;
1303 	}
1304 	return fwd;
1305 }
1306 
1307 extern void ip_vs_nat_icmp(struct sk_buff *skb, struct ip_vs_protocol *pp,
1308 			   struct ip_vs_conn *cp, int dir);
1309 
1310 #ifdef CONFIG_IP_VS_IPV6
1311 extern void ip_vs_nat_icmp_v6(struct sk_buff *skb, struct ip_vs_protocol *pp,
1312 			      struct ip_vs_conn *cp, int dir);
1313 #endif
1314 
1315 extern __sum16 ip_vs_checksum_complete(struct sk_buff *skb, int offset);
1316 
1317 static inline __wsum ip_vs_check_diff4(__be32 old, __be32 new, __wsum oldsum)
1318 {
1319 	__be32 diff[2] = { ~old, new };
1320 
1321 	return csum_partial(diff, sizeof(diff), oldsum);
1322 }
1323 
1324 #ifdef CONFIG_IP_VS_IPV6
1325 static inline __wsum ip_vs_check_diff16(const __be32 *old, const __be32 *new,
1326 					__wsum oldsum)
1327 {
1328 	__be32 diff[8] = { ~old[3], ~old[2], ~old[1], ~old[0],
1329 			    new[3],  new[2],  new[1],  new[0] };
1330 
1331 	return csum_partial(diff, sizeof(diff), oldsum);
1332 }
1333 #endif
1334 
1335 static inline __wsum ip_vs_check_diff2(__be16 old, __be16 new, __wsum oldsum)
1336 {
1337 	__be16 diff[2] = { ~old, new };
1338 
1339 	return csum_partial(diff, sizeof(diff), oldsum);
1340 }
1341 
1342 /*
1343  * Forget current conntrack (unconfirmed) and attach notrack entry
1344  */
1345 static inline void ip_vs_notrack(struct sk_buff *skb)
1346 {
1347 #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
1348 	enum ip_conntrack_info ctinfo;
1349 	struct nf_conn *ct = nf_ct_get(skb, &ctinfo);
1350 
1351 	if (!ct || !nf_ct_is_untracked(ct)) {
1352 		nf_reset(skb);
1353 		skb->nfct = &nf_ct_untracked_get()->ct_general;
1354 		skb->nfctinfo = IP_CT_NEW;
1355 		nf_conntrack_get(skb->nfct);
1356 	}
1357 #endif
1358 }
1359 
1360 #ifdef CONFIG_IP_VS_NFCT
1361 /*
1362  *      Netfilter connection tracking
1363  *      (from ip_vs_nfct.c)
1364  */
1365 static inline int ip_vs_conntrack_enabled(struct netns_ipvs *ipvs)
1366 {
1367 #ifdef CONFIG_SYSCTL
1368 	return ipvs->sysctl_conntrack;
1369 #else
1370 	return 0;
1371 #endif
1372 }
1373 
1374 extern void ip_vs_update_conntrack(struct sk_buff *skb, struct ip_vs_conn *cp,
1375 				   int outin);
1376 extern int ip_vs_confirm_conntrack(struct sk_buff *skb, struct ip_vs_conn *cp);
1377 extern void ip_vs_nfct_expect_related(struct sk_buff *skb, struct nf_conn *ct,
1378 				      struct ip_vs_conn *cp, u_int8_t proto,
1379 				      const __be16 port, int from_rs);
1380 extern void ip_vs_conn_drop_conntrack(struct ip_vs_conn *cp);
1381 
1382 #else
1383 
1384 static inline int ip_vs_conntrack_enabled(struct netns_ipvs *ipvs)
1385 {
1386 	return 0;
1387 }
1388 
1389 static inline void ip_vs_update_conntrack(struct sk_buff *skb,
1390 					  struct ip_vs_conn *cp, int outin)
1391 {
1392 }
1393 
1394 static inline int ip_vs_confirm_conntrack(struct sk_buff *skb,
1395 					  struct ip_vs_conn *cp)
1396 {
1397 	return NF_ACCEPT;
1398 }
1399 
1400 static inline void ip_vs_conn_drop_conntrack(struct ip_vs_conn *cp)
1401 {
1402 }
1403 /* CONFIG_IP_VS_NFCT */
1404 #endif
1405 
1406 static inline unsigned int
1407 ip_vs_dest_conn_overhead(struct ip_vs_dest *dest)
1408 {
1409 	/*
1410 	 * We think the overhead of processing active connections is 256
1411 	 * times higher than that of inactive connections in average. (This
1412 	 * 256 times might not be accurate, we will change it later) We
1413 	 * use the following formula to estimate the overhead now:
1414 	 *		  dest->activeconns*256 + dest->inactconns
1415 	 */
1416 	return (atomic_read(&dest->activeconns) << 8) +
1417 		atomic_read(&dest->inactconns);
1418 }
1419 
1420 #endif /* __KERNEL__ */
1421 
1422 #endif	/* _NET_IP_VS_H */
1423