xref: /linux/include/net/ip_vs.h (revision d39d0ed196aa1685bb24771e92f78633c66ac9cb)
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 
29 
30 /* Connections' size value needed by ip_vs_ctl.c */
31 extern int ip_vs_conn_tab_size;
32 
33 
34 struct ip_vs_iphdr {
35 	int len;
36 	__u8 protocol;
37 	union nf_inet_addr saddr;
38 	union nf_inet_addr daddr;
39 };
40 
41 static inline void
42 ip_vs_fill_iphdr(int af, const void *nh, struct ip_vs_iphdr *iphdr)
43 {
44 #ifdef CONFIG_IP_VS_IPV6
45 	if (af == AF_INET6) {
46 		const struct ipv6hdr *iph = nh;
47 		iphdr->len = sizeof(struct ipv6hdr);
48 		iphdr->protocol = iph->nexthdr;
49 		ipv6_addr_copy(&iphdr->saddr.in6, &iph->saddr);
50 		ipv6_addr_copy(&iphdr->daddr.in6, &iph->daddr);
51 	} else
52 #endif
53 	{
54 		const struct iphdr *iph = nh;
55 		iphdr->len = iph->ihl * 4;
56 		iphdr->protocol = iph->protocol;
57 		iphdr->saddr.ip = iph->saddr;
58 		iphdr->daddr.ip = iph->daddr;
59 	}
60 }
61 
62 static inline void ip_vs_addr_copy(int af, union nf_inet_addr *dst,
63 				   const union nf_inet_addr *src)
64 {
65 #ifdef CONFIG_IP_VS_IPV6
66 	if (af == AF_INET6)
67 		ipv6_addr_copy(&dst->in6, &src->in6);
68 	else
69 #endif
70 	dst->ip = src->ip;
71 }
72 
73 static inline int ip_vs_addr_equal(int af, const union nf_inet_addr *a,
74 				   const union nf_inet_addr *b)
75 {
76 #ifdef CONFIG_IP_VS_IPV6
77 	if (af == AF_INET6)
78 		return ipv6_addr_equal(&a->in6, &b->in6);
79 #endif
80 	return a->ip == b->ip;
81 }
82 
83 #ifdef CONFIG_IP_VS_DEBUG
84 #include <linux/net.h>
85 
86 extern int ip_vs_get_debug_level(void);
87 
88 static inline const char *ip_vs_dbg_addr(int af, char *buf, size_t buf_len,
89 					 const union nf_inet_addr *addr,
90 					 int *idx)
91 {
92 	int len;
93 #ifdef CONFIG_IP_VS_IPV6
94 	if (af == AF_INET6)
95 		len = snprintf(&buf[*idx], buf_len - *idx, "[%pI6]",
96 			       &addr->in6) + 1;
97 	else
98 #endif
99 		len = snprintf(&buf[*idx], buf_len - *idx, "%pI4",
100 			       &addr->ip) + 1;
101 
102 	*idx += len;
103 	BUG_ON(*idx > buf_len + 1);
104 	return &buf[*idx - len];
105 }
106 
107 #define IP_VS_DBG_BUF(level, msg, ...)					\
108 	do {								\
109 		char ip_vs_dbg_buf[160];				\
110 		int ip_vs_dbg_idx = 0;					\
111 		if (level <= ip_vs_get_debug_level())			\
112 			printk(KERN_DEBUG pr_fmt(msg), ##__VA_ARGS__);	\
113 	} while (0)
114 #define IP_VS_ERR_BUF(msg...)						\
115 	do {								\
116 		char ip_vs_dbg_buf[160];				\
117 		int ip_vs_dbg_idx = 0;					\
118 		pr_err(msg);						\
119 	} while (0)
120 
121 /* Only use from within IP_VS_DBG_BUF() or IP_VS_ERR_BUF macros */
122 #define IP_VS_DBG_ADDR(af, addr)					\
123 	ip_vs_dbg_addr(af, ip_vs_dbg_buf,				\
124 		       sizeof(ip_vs_dbg_buf), addr,			\
125 		       &ip_vs_dbg_idx)
126 
127 #define IP_VS_DBG(level, msg, ...)					\
128 	do {								\
129 		if (level <= ip_vs_get_debug_level())			\
130 			printk(KERN_DEBUG pr_fmt(msg), ##__VA_ARGS__);	\
131 	} while (0)
132 #define IP_VS_DBG_RL(msg, ...)						\
133 	do {								\
134 		if (net_ratelimit())					\
135 			printk(KERN_DEBUG pr_fmt(msg), ##__VA_ARGS__);	\
136 	} while (0)
137 #define IP_VS_DBG_PKT(level, pp, skb, ofs, msg)				\
138 	do {								\
139 		if (level <= ip_vs_get_debug_level())			\
140 			pp->debug_packet(pp, skb, ofs, msg);		\
141 	} while (0)
142 #define IP_VS_DBG_RL_PKT(level, pp, skb, ofs, msg)			\
143 	do {								\
144 		if (level <= ip_vs_get_debug_level() &&			\
145 		    net_ratelimit())					\
146 			pp->debug_packet(pp, skb, ofs, msg);		\
147 	} while (0)
148 #else	/* NO DEBUGGING at ALL */
149 #define IP_VS_DBG_BUF(level, msg...)  do {} while (0)
150 #define IP_VS_ERR_BUF(msg...)  do {} while (0)
151 #define IP_VS_DBG(level, msg...)  do {} while (0)
152 #define IP_VS_DBG_RL(msg...)  do {} while (0)
153 #define IP_VS_DBG_PKT(level, pp, skb, ofs, msg)		do {} while (0)
154 #define IP_VS_DBG_RL_PKT(level, pp, skb, ofs, msg)	do {} while (0)
155 #endif
156 
157 #define IP_VS_BUG() BUG()
158 #define IP_VS_ERR_RL(msg, ...)						\
159 	do {								\
160 		if (net_ratelimit())					\
161 			pr_err(msg, ##__VA_ARGS__);			\
162 	} while (0)
163 
164 #ifdef CONFIG_IP_VS_DEBUG
165 #define EnterFunction(level)						\
166 	do {								\
167 		if (level <= ip_vs_get_debug_level())			\
168 			printk(KERN_DEBUG				\
169 			       pr_fmt("Enter: %s, %s line %i\n"),	\
170 			       __func__, __FILE__, __LINE__);		\
171 	} while (0)
172 #define LeaveFunction(level)						\
173 	do {								\
174 		if (level <= ip_vs_get_debug_level())			\
175 			printk(KERN_DEBUG				\
176 			       pr_fmt("Leave: %s, %s line %i\n"),	\
177 			       __func__, __FILE__, __LINE__);		\
178 	} while (0)
179 #else
180 #define EnterFunction(level)   do {} while (0)
181 #define LeaveFunction(level)   do {} while (0)
182 #endif
183 
184 #define	IP_VS_WAIT_WHILE(expr)	while (expr) { cpu_relax(); }
185 
186 
187 /*
188  *      The port number of FTP service (in network order).
189  */
190 #define FTPPORT  cpu_to_be16(21)
191 #define FTPDATA  cpu_to_be16(20)
192 
193 /*
194  *      TCP State Values
195  */
196 enum {
197 	IP_VS_TCP_S_NONE = 0,
198 	IP_VS_TCP_S_ESTABLISHED,
199 	IP_VS_TCP_S_SYN_SENT,
200 	IP_VS_TCP_S_SYN_RECV,
201 	IP_VS_TCP_S_FIN_WAIT,
202 	IP_VS_TCP_S_TIME_WAIT,
203 	IP_VS_TCP_S_CLOSE,
204 	IP_VS_TCP_S_CLOSE_WAIT,
205 	IP_VS_TCP_S_LAST_ACK,
206 	IP_VS_TCP_S_LISTEN,
207 	IP_VS_TCP_S_SYNACK,
208 	IP_VS_TCP_S_LAST
209 };
210 
211 /*
212  *	UDP State Values
213  */
214 enum {
215 	IP_VS_UDP_S_NORMAL,
216 	IP_VS_UDP_S_LAST,
217 };
218 
219 /*
220  *	ICMP State Values
221  */
222 enum {
223 	IP_VS_ICMP_S_NORMAL,
224 	IP_VS_ICMP_S_LAST,
225 };
226 
227 /*
228  *	SCTP State Values
229  */
230 enum ip_vs_sctp_states {
231 	IP_VS_SCTP_S_NONE,
232 	IP_VS_SCTP_S_INIT_CLI,
233 	IP_VS_SCTP_S_INIT_SER,
234 	IP_VS_SCTP_S_INIT_ACK_CLI,
235 	IP_VS_SCTP_S_INIT_ACK_SER,
236 	IP_VS_SCTP_S_ECHO_CLI,
237 	IP_VS_SCTP_S_ECHO_SER,
238 	IP_VS_SCTP_S_ESTABLISHED,
239 	IP_VS_SCTP_S_SHUT_CLI,
240 	IP_VS_SCTP_S_SHUT_SER,
241 	IP_VS_SCTP_S_SHUT_ACK_CLI,
242 	IP_VS_SCTP_S_SHUT_ACK_SER,
243 	IP_VS_SCTP_S_CLOSED,
244 	IP_VS_SCTP_S_LAST
245 };
246 
247 /*
248  *	Delta sequence info structure
249  *	Each ip_vs_conn has 2 (output AND input seq. changes).
250  *      Only used in the VS/NAT.
251  */
252 struct ip_vs_seq {
253 	__u32			init_seq;	/* Add delta from this seq */
254 	__u32			delta;		/* Delta in sequence numbers */
255 	__u32			previous_delta;	/* Delta in sequence numbers
256 						   before last resized pkt */
257 };
258 
259 
260 /*
261  *	IPVS statistics objects
262  */
263 struct ip_vs_estimator {
264 	struct list_head	list;
265 
266 	u64			last_inbytes;
267 	u64			last_outbytes;
268 	u32			last_conns;
269 	u32			last_inpkts;
270 	u32			last_outpkts;
271 
272 	u32			cps;
273 	u32			inpps;
274 	u32			outpps;
275 	u32			inbps;
276 	u32			outbps;
277 };
278 
279 struct ip_vs_stats {
280 	struct ip_vs_stats_user	ustats;         /* statistics */
281 	struct ip_vs_estimator	est;		/* estimator */
282 
283 	spinlock_t              lock;           /* spin lock */
284 };
285 
286 struct dst_entry;
287 struct iphdr;
288 struct ip_vs_conn;
289 struct ip_vs_app;
290 struct sk_buff;
291 
292 struct ip_vs_protocol {
293 	struct ip_vs_protocol	*next;
294 	char			*name;
295 	u16			protocol;
296 	u16			num_states;
297 	int			dont_defrag;
298 	atomic_t		appcnt;		/* counter of proto app incs */
299 	int			*timeout_table;	/* protocol timeout table */
300 
301 	void (*init)(struct ip_vs_protocol *pp);
302 
303 	void (*exit)(struct ip_vs_protocol *pp);
304 
305 	int (*conn_schedule)(int af, struct sk_buff *skb,
306 			     struct ip_vs_protocol *pp,
307 			     int *verdict, struct ip_vs_conn **cpp);
308 
309 	struct ip_vs_conn *
310 	(*conn_in_get)(int af,
311 		       const struct sk_buff *skb,
312 		       struct ip_vs_protocol *pp,
313 		       const struct ip_vs_iphdr *iph,
314 		       unsigned int proto_off,
315 		       int inverse);
316 
317 	struct ip_vs_conn *
318 	(*conn_out_get)(int af,
319 			const struct sk_buff *skb,
320 			struct ip_vs_protocol *pp,
321 			const struct ip_vs_iphdr *iph,
322 			unsigned int proto_off,
323 			int inverse);
324 
325 	int (*snat_handler)(struct sk_buff *skb,
326 			    struct ip_vs_protocol *pp, struct ip_vs_conn *cp);
327 
328 	int (*dnat_handler)(struct sk_buff *skb,
329 			    struct ip_vs_protocol *pp, struct ip_vs_conn *cp);
330 
331 	int (*csum_check)(int af, struct sk_buff *skb,
332 			  struct ip_vs_protocol *pp);
333 
334 	const char *(*state_name)(int state);
335 
336 	int (*state_transition)(struct ip_vs_conn *cp, int direction,
337 				const struct sk_buff *skb,
338 				struct ip_vs_protocol *pp);
339 
340 	int (*register_app)(struct ip_vs_app *inc);
341 
342 	void (*unregister_app)(struct ip_vs_app *inc);
343 
344 	int (*app_conn_bind)(struct ip_vs_conn *cp);
345 
346 	void (*debug_packet)(struct ip_vs_protocol *pp,
347 			     const struct sk_buff *skb,
348 			     int offset,
349 			     const char *msg);
350 
351 	void (*timeout_change)(struct ip_vs_protocol *pp, int flags);
352 
353 	int (*set_state_timeout)(struct ip_vs_protocol *pp, char *sname, int to);
354 };
355 
356 extern struct ip_vs_protocol * ip_vs_proto_get(unsigned short proto);
357 
358 /*
359  *	IP_VS structure allocated for each dynamically scheduled connection
360  */
361 struct ip_vs_conn {
362 	struct list_head        c_list;         /* hashed list heads */
363 
364 	/* Protocol, addresses and port numbers */
365 	u16                      af;		/* address family */
366 	union nf_inet_addr       caddr;          /* client address */
367 	union nf_inet_addr       vaddr;          /* virtual address */
368 	union nf_inet_addr       daddr;          /* destination address */
369 	__be16                   cport;
370 	__be16                   vport;
371 	__be16                   dport;
372 	__u16                   protocol;       /* Which protocol (TCP/UDP) */
373 
374 	/* counter and timer */
375 	atomic_t		refcnt;		/* reference count */
376 	struct timer_list	timer;		/* Expiration timer */
377 	volatile unsigned long	timeout;	/* timeout */
378 
379 	/* Flags and state transition */
380 	spinlock_t              lock;           /* lock for state transition */
381 	volatile __u16          flags;          /* status flags */
382 	volatile __u16          state;          /* state info */
383 	volatile __u16          old_state;      /* old state, to be used for
384 						 * state transition triggerd
385 						 * synchronization
386 						 */
387 
388 	/* Control members */
389 	struct ip_vs_conn       *control;       /* Master control connection */
390 	atomic_t                n_control;      /* Number of controlled ones */
391 	struct ip_vs_dest       *dest;          /* real server */
392 	atomic_t                in_pkts;        /* incoming packet counter */
393 
394 	/* packet transmitter for different forwarding methods.  If it
395 	   mangles the packet, it must return NF_DROP or better NF_STOLEN,
396 	   otherwise this must be changed to a sk_buff **.
397 	 */
398 	int (*packet_xmit)(struct sk_buff *skb, struct ip_vs_conn *cp,
399 			   struct ip_vs_protocol *pp);
400 
401 	/* Note: we can group the following members into a structure,
402 	   in order to save more space, and the following members are
403 	   only used in VS/NAT anyway */
404 	struct ip_vs_app        *app;           /* bound ip_vs_app object */
405 	void                    *app_data;      /* Application private data */
406 	struct ip_vs_seq        in_seq;         /* incoming seq. struct */
407 	struct ip_vs_seq        out_seq;        /* outgoing seq. struct */
408 };
409 
410 
411 /*
412  *	Extended internal versions of struct ip_vs_service_user and
413  *	ip_vs_dest_user for IPv6 support.
414  *
415  *	We need these to conveniently pass around service and destination
416  *	options, but unfortunately, we also need to keep the old definitions to
417  *	maintain userspace backwards compatibility for the setsockopt interface.
418  */
419 struct ip_vs_service_user_kern {
420 	/* virtual service addresses */
421 	u16			af;
422 	u16			protocol;
423 	union nf_inet_addr	addr;		/* virtual ip address */
424 	u16			port;
425 	u32			fwmark;		/* firwall mark of service */
426 
427 	/* virtual service options */
428 	char			*sched_name;
429 	unsigned		flags;		/* virtual service flags */
430 	unsigned		timeout;	/* persistent timeout in sec */
431 	u32			netmask;	/* persistent netmask */
432 };
433 
434 
435 struct ip_vs_dest_user_kern {
436 	/* destination server address */
437 	union nf_inet_addr	addr;
438 	u16			port;
439 
440 	/* real server options */
441 	unsigned		conn_flags;	/* connection flags */
442 	int			weight;		/* destination weight */
443 
444 	/* thresholds for active connections */
445 	u32			u_threshold;	/* upper threshold */
446 	u32			l_threshold;	/* lower threshold */
447 };
448 
449 
450 /*
451  *	The information about the virtual service offered to the net
452  *	and the forwarding entries
453  */
454 struct ip_vs_service {
455 	struct list_head	s_list;   /* for normal service table */
456 	struct list_head	f_list;   /* for fwmark-based service table */
457 	atomic_t		refcnt;   /* reference counter */
458 	atomic_t		usecnt;   /* use counter */
459 
460 	u16			af;       /* address family */
461 	__u16			protocol; /* which protocol (TCP/UDP) */
462 	union nf_inet_addr	addr;	  /* IP address for virtual service */
463 	__be16			port;	  /* port number for the service */
464 	__u32                   fwmark;   /* firewall mark of the service */
465 	unsigned		flags;	  /* service status flags */
466 	unsigned		timeout;  /* persistent timeout in ticks */
467 	__be32			netmask;  /* grouping granularity */
468 
469 	struct list_head	destinations;  /* real server d-linked list */
470 	__u32			num_dests;     /* number of servers */
471 	struct ip_vs_stats      stats;         /* statistics for the service */
472 	struct ip_vs_app	*inc;	  /* bind conns to this app inc */
473 
474 	/* for scheduling */
475 	struct ip_vs_scheduler	*scheduler;    /* bound scheduler object */
476 	rwlock_t		sched_lock;    /* lock sched_data */
477 	void			*sched_data;   /* scheduler application data */
478 };
479 
480 
481 /*
482  *	The real server destination forwarding entry
483  *	with ip address, port number, and so on.
484  */
485 struct ip_vs_dest {
486 	struct list_head	n_list;   /* for the dests in the service */
487 	struct list_head	d_list;   /* for table with all the dests */
488 
489 	u16			af;		/* address family */
490 	union nf_inet_addr	addr;		/* IP address of the server */
491 	__be16			port;		/* port number of the server */
492 	volatile unsigned	flags;		/* dest status flags */
493 	atomic_t		conn_flags;	/* flags to copy to conn */
494 	atomic_t		weight;		/* server weight */
495 
496 	atomic_t		refcnt;		/* reference counter */
497 	struct ip_vs_stats      stats;          /* statistics */
498 
499 	/* connection counters and thresholds */
500 	atomic_t		activeconns;	/* active connections */
501 	atomic_t		inactconns;	/* inactive connections */
502 	atomic_t		persistconns;	/* persistent connections */
503 	__u32			u_threshold;	/* upper threshold */
504 	__u32			l_threshold;	/* lower threshold */
505 
506 	/* for destination cache */
507 	spinlock_t		dst_lock;	/* lock of dst_cache */
508 	struct dst_entry	*dst_cache;	/* destination cache entry */
509 	u32			dst_rtos;	/* RT_TOS(tos) for dst */
510 
511 	/* for virtual service */
512 	struct ip_vs_service	*svc;		/* service it belongs to */
513 	__u16			protocol;	/* which protocol (TCP/UDP) */
514 	union nf_inet_addr	vaddr;		/* virtual IP address */
515 	__be16			vport;		/* virtual port number */
516 	__u32			vfwmark;	/* firewall mark of service */
517 };
518 
519 
520 /*
521  *	The scheduler object
522  */
523 struct ip_vs_scheduler {
524 	struct list_head	n_list;		/* d-linked list head */
525 	char			*name;		/* scheduler name */
526 	atomic_t		refcnt;		/* reference counter */
527 	struct module		*module;	/* THIS_MODULE/NULL */
528 
529 	/* scheduler initializing service */
530 	int (*init_service)(struct ip_vs_service *svc);
531 	/* scheduling service finish */
532 	int (*done_service)(struct ip_vs_service *svc);
533 	/* scheduler updating service */
534 	int (*update_service)(struct ip_vs_service *svc);
535 
536 	/* selecting a server from the given service */
537 	struct ip_vs_dest* (*schedule)(struct ip_vs_service *svc,
538 				       const struct sk_buff *skb);
539 };
540 
541 
542 /*
543  *	The application module object (a.k.a. app incarnation)
544  */
545 struct ip_vs_app {
546 	struct list_head	a_list;		/* member in app list */
547 	int			type;		/* IP_VS_APP_TYPE_xxx */
548 	char			*name;		/* application module name */
549 	__u16			protocol;
550 	struct module		*module;	/* THIS_MODULE/NULL */
551 	struct list_head	incs_list;	/* list of incarnations */
552 
553 	/* members for application incarnations */
554 	struct list_head	p_list;		/* member in proto app list */
555 	struct ip_vs_app	*app;		/* its real application */
556 	__be16			port;		/* port number in net order */
557 	atomic_t		usecnt;		/* usage counter */
558 
559 	/* output hook: return false if can't linearize. diff set for TCP.  */
560 	int (*pkt_out)(struct ip_vs_app *, struct ip_vs_conn *,
561 		       struct sk_buff *, int *diff);
562 
563 	/* input hook: return false if can't linearize. diff set for TCP. */
564 	int (*pkt_in)(struct ip_vs_app *, struct ip_vs_conn *,
565 		      struct sk_buff *, int *diff);
566 
567 	/* ip_vs_app initializer */
568 	int (*init_conn)(struct ip_vs_app *, struct ip_vs_conn *);
569 
570 	/* ip_vs_app finish */
571 	int (*done_conn)(struct ip_vs_app *, struct ip_vs_conn *);
572 
573 
574 	/* not used now */
575 	int (*bind_conn)(struct ip_vs_app *, struct ip_vs_conn *,
576 			 struct ip_vs_protocol *);
577 
578 	void (*unbind_conn)(struct ip_vs_app *, struct ip_vs_conn *);
579 
580 	int *			timeout_table;
581 	int *			timeouts;
582 	int			timeouts_size;
583 
584 	int (*conn_schedule)(struct sk_buff *skb, struct ip_vs_app *app,
585 			     int *verdict, struct ip_vs_conn **cpp);
586 
587 	struct ip_vs_conn *
588 	(*conn_in_get)(const struct sk_buff *skb, struct ip_vs_app *app,
589 		       const struct iphdr *iph, unsigned int proto_off,
590 		       int inverse);
591 
592 	struct ip_vs_conn *
593 	(*conn_out_get)(const struct sk_buff *skb, struct ip_vs_app *app,
594 			const struct iphdr *iph, unsigned int proto_off,
595 			int inverse);
596 
597 	int (*state_transition)(struct ip_vs_conn *cp, int direction,
598 				const struct sk_buff *skb,
599 				struct ip_vs_app *app);
600 
601 	void (*timeout_change)(struct ip_vs_app *app, int flags);
602 };
603 
604 
605 /*
606  *      IPVS core functions
607  *      (from ip_vs_core.c)
608  */
609 extern const char *ip_vs_proto_name(unsigned proto);
610 extern void ip_vs_init_hash_table(struct list_head *table, int rows);
611 #define IP_VS_INIT_HASH_TABLE(t) ip_vs_init_hash_table((t), ARRAY_SIZE((t)))
612 
613 #define IP_VS_APP_TYPE_FTP	1
614 
615 /*
616  *     ip_vs_conn handling functions
617  *     (from ip_vs_conn.c)
618  */
619 
620 enum {
621 	IP_VS_DIR_INPUT = 0,
622 	IP_VS_DIR_OUTPUT,
623 	IP_VS_DIR_INPUT_ONLY,
624 	IP_VS_DIR_LAST,
625 };
626 
627 extern struct ip_vs_conn *ip_vs_conn_in_get
628 (int af, int protocol, const union nf_inet_addr *s_addr, __be16 s_port,
629  const union nf_inet_addr *d_addr, __be16 d_port);
630 
631 extern struct ip_vs_conn *ip_vs_ct_in_get
632 (int af, int protocol, const union nf_inet_addr *s_addr, __be16 s_port,
633  const union nf_inet_addr *d_addr, __be16 d_port);
634 
635 struct ip_vs_conn * ip_vs_conn_in_get_proto(int af, const struct sk_buff *skb,
636 					    struct ip_vs_protocol *pp,
637 					    const struct ip_vs_iphdr *iph,
638 					    unsigned int proto_off,
639 					    int inverse);
640 
641 extern struct ip_vs_conn *ip_vs_conn_out_get
642 (int af, int protocol, const union nf_inet_addr *s_addr, __be16 s_port,
643  const union nf_inet_addr *d_addr, __be16 d_port);
644 
645 struct ip_vs_conn * ip_vs_conn_out_get_proto(int af, const struct sk_buff *skb,
646 					     struct ip_vs_protocol *pp,
647 					     const struct ip_vs_iphdr *iph,
648 					     unsigned int proto_off,
649 					     int inverse);
650 
651 /* put back the conn without restarting its timer */
652 static inline void __ip_vs_conn_put(struct ip_vs_conn *cp)
653 {
654 	atomic_dec(&cp->refcnt);
655 }
656 extern void ip_vs_conn_put(struct ip_vs_conn *cp);
657 extern void ip_vs_conn_fill_cport(struct ip_vs_conn *cp, __be16 cport);
658 
659 extern struct ip_vs_conn *
660 ip_vs_conn_new(int af, int proto, const union nf_inet_addr *caddr, __be16 cport,
661 	       const union nf_inet_addr *vaddr, __be16 vport,
662 	       const union nf_inet_addr *daddr, __be16 dport, unsigned flags,
663 	       struct ip_vs_dest *dest);
664 extern void ip_vs_conn_expire_now(struct ip_vs_conn *cp);
665 
666 extern const char * ip_vs_state_name(__u16 proto, int state);
667 
668 extern void ip_vs_tcp_conn_listen(struct ip_vs_conn *cp);
669 extern int ip_vs_check_template(struct ip_vs_conn *ct);
670 extern void ip_vs_random_dropentry(void);
671 extern int ip_vs_conn_init(void);
672 extern void ip_vs_conn_cleanup(void);
673 
674 static inline void ip_vs_control_del(struct ip_vs_conn *cp)
675 {
676 	struct ip_vs_conn *ctl_cp = cp->control;
677 	if (!ctl_cp) {
678 		IP_VS_ERR_BUF("request control DEL for uncontrolled: "
679 			      "%s:%d to %s:%d\n",
680 			      IP_VS_DBG_ADDR(cp->af, &cp->caddr),
681 			      ntohs(cp->cport),
682 			      IP_VS_DBG_ADDR(cp->af, &cp->vaddr),
683 			      ntohs(cp->vport));
684 
685 		return;
686 	}
687 
688 	IP_VS_DBG_BUF(7, "DELeting control for: "
689 		      "cp.dst=%s:%d ctl_cp.dst=%s:%d\n",
690 		      IP_VS_DBG_ADDR(cp->af, &cp->caddr),
691 		      ntohs(cp->cport),
692 		      IP_VS_DBG_ADDR(cp->af, &ctl_cp->caddr),
693 		      ntohs(ctl_cp->cport));
694 
695 	cp->control = NULL;
696 	if (atomic_read(&ctl_cp->n_control) == 0) {
697 		IP_VS_ERR_BUF("BUG control DEL with n=0 : "
698 			      "%s:%d to %s:%d\n",
699 			      IP_VS_DBG_ADDR(cp->af, &cp->caddr),
700 			      ntohs(cp->cport),
701 			      IP_VS_DBG_ADDR(cp->af, &cp->vaddr),
702 			      ntohs(cp->vport));
703 
704 		return;
705 	}
706 	atomic_dec(&ctl_cp->n_control);
707 }
708 
709 static inline void
710 ip_vs_control_add(struct ip_vs_conn *cp, struct ip_vs_conn *ctl_cp)
711 {
712 	if (cp->control) {
713 		IP_VS_ERR_BUF("request control ADD for already controlled: "
714 			      "%s:%d to %s:%d\n",
715 			      IP_VS_DBG_ADDR(cp->af, &cp->caddr),
716 			      ntohs(cp->cport),
717 			      IP_VS_DBG_ADDR(cp->af, &cp->vaddr),
718 			      ntohs(cp->vport));
719 
720 		ip_vs_control_del(cp);
721 	}
722 
723 	IP_VS_DBG_BUF(7, "ADDing control for: "
724 		      "cp.dst=%s:%d ctl_cp.dst=%s:%d\n",
725 		      IP_VS_DBG_ADDR(cp->af, &cp->caddr),
726 		      ntohs(cp->cport),
727 		      IP_VS_DBG_ADDR(cp->af, &ctl_cp->caddr),
728 		      ntohs(ctl_cp->cport));
729 
730 	cp->control = ctl_cp;
731 	atomic_inc(&ctl_cp->n_control);
732 }
733 
734 
735 /*
736  *      IPVS application functions
737  *      (from ip_vs_app.c)
738  */
739 #define IP_VS_APP_MAX_PORTS  8
740 extern int register_ip_vs_app(struct ip_vs_app *app);
741 extern void unregister_ip_vs_app(struct ip_vs_app *app);
742 extern int ip_vs_bind_app(struct ip_vs_conn *cp, struct ip_vs_protocol *pp);
743 extern void ip_vs_unbind_app(struct ip_vs_conn *cp);
744 extern int
745 register_ip_vs_app_inc(struct ip_vs_app *app, __u16 proto, __u16 port);
746 extern int ip_vs_app_inc_get(struct ip_vs_app *inc);
747 extern void ip_vs_app_inc_put(struct ip_vs_app *inc);
748 
749 extern int ip_vs_app_pkt_out(struct ip_vs_conn *, struct sk_buff *skb);
750 extern int ip_vs_app_pkt_in(struct ip_vs_conn *, struct sk_buff *skb);
751 extern int ip_vs_app_init(void);
752 extern void ip_vs_app_cleanup(void);
753 
754 
755 /*
756  *	IPVS protocol functions (from ip_vs_proto.c)
757  */
758 extern int ip_vs_protocol_init(void);
759 extern void ip_vs_protocol_cleanup(void);
760 extern void ip_vs_protocol_timeout_change(int flags);
761 extern int *ip_vs_create_timeout_table(int *table, int size);
762 extern int
763 ip_vs_set_state_timeout(int *table, int num, const char *const *names,
764 			const char *name, int to);
765 extern void
766 ip_vs_tcpudp_debug_packet(struct ip_vs_protocol *pp, const struct sk_buff *skb,
767 			  int offset, const char *msg);
768 
769 extern struct ip_vs_protocol ip_vs_protocol_tcp;
770 extern struct ip_vs_protocol ip_vs_protocol_udp;
771 extern struct ip_vs_protocol ip_vs_protocol_icmp;
772 extern struct ip_vs_protocol ip_vs_protocol_esp;
773 extern struct ip_vs_protocol ip_vs_protocol_ah;
774 extern struct ip_vs_protocol ip_vs_protocol_sctp;
775 
776 /*
777  *      Registering/unregistering scheduler functions
778  *      (from ip_vs_sched.c)
779  */
780 extern int register_ip_vs_scheduler(struct ip_vs_scheduler *scheduler);
781 extern int unregister_ip_vs_scheduler(struct ip_vs_scheduler *scheduler);
782 extern int ip_vs_bind_scheduler(struct ip_vs_service *svc,
783 				struct ip_vs_scheduler *scheduler);
784 extern int ip_vs_unbind_scheduler(struct ip_vs_service *svc);
785 extern struct ip_vs_scheduler *ip_vs_scheduler_get(const char *sched_name);
786 extern void ip_vs_scheduler_put(struct ip_vs_scheduler *scheduler);
787 extern struct ip_vs_conn *
788 ip_vs_schedule(struct ip_vs_service *svc, const struct sk_buff *skb);
789 extern int ip_vs_leave(struct ip_vs_service *svc, struct sk_buff *skb,
790 			struct ip_vs_protocol *pp);
791 
792 
793 /*
794  *      IPVS control data and functions (from ip_vs_ctl.c)
795  */
796 extern int sysctl_ip_vs_cache_bypass;
797 extern int sysctl_ip_vs_expire_nodest_conn;
798 extern int sysctl_ip_vs_expire_quiescent_template;
799 extern int sysctl_ip_vs_sync_threshold[2];
800 extern int sysctl_ip_vs_nat_icmp_send;
801 extern struct ip_vs_stats ip_vs_stats;
802 extern const struct ctl_path net_vs_ctl_path[];
803 
804 extern struct ip_vs_service *
805 ip_vs_service_get(int af, __u32 fwmark, __u16 protocol,
806 		  const union nf_inet_addr *vaddr, __be16 vport);
807 
808 static inline void ip_vs_service_put(struct ip_vs_service *svc)
809 {
810 	atomic_dec(&svc->usecnt);
811 }
812 
813 extern struct ip_vs_dest *
814 ip_vs_lookup_real_service(int af, __u16 protocol,
815 			  const union nf_inet_addr *daddr, __be16 dport);
816 
817 extern int ip_vs_use_count_inc(void);
818 extern void ip_vs_use_count_dec(void);
819 extern int ip_vs_control_init(void);
820 extern void ip_vs_control_cleanup(void);
821 extern struct ip_vs_dest *
822 ip_vs_find_dest(int af, const union nf_inet_addr *daddr, __be16 dport,
823 		const union nf_inet_addr *vaddr, __be16 vport, __u16 protocol);
824 extern struct ip_vs_dest *ip_vs_try_bind_dest(struct ip_vs_conn *cp);
825 
826 
827 /*
828  *      IPVS sync daemon data and function prototypes
829  *      (from ip_vs_sync.c)
830  */
831 extern volatile int ip_vs_sync_state;
832 extern volatile int ip_vs_master_syncid;
833 extern volatile int ip_vs_backup_syncid;
834 extern char ip_vs_master_mcast_ifn[IP_VS_IFNAME_MAXLEN];
835 extern char ip_vs_backup_mcast_ifn[IP_VS_IFNAME_MAXLEN];
836 extern int start_sync_thread(int state, char *mcast_ifn, __u8 syncid);
837 extern int stop_sync_thread(int state);
838 extern void ip_vs_sync_conn(struct ip_vs_conn *cp);
839 
840 
841 /*
842  *      IPVS rate estimator prototypes (from ip_vs_est.c)
843  */
844 extern int ip_vs_estimator_init(void);
845 extern void ip_vs_estimator_cleanup(void);
846 extern void ip_vs_new_estimator(struct ip_vs_stats *stats);
847 extern void ip_vs_kill_estimator(struct ip_vs_stats *stats);
848 extern void ip_vs_zero_estimator(struct ip_vs_stats *stats);
849 
850 /*
851  *	Various IPVS packet transmitters (from ip_vs_xmit.c)
852  */
853 extern int ip_vs_null_xmit
854 (struct sk_buff *skb, struct ip_vs_conn *cp, struct ip_vs_protocol *pp);
855 extern int ip_vs_bypass_xmit
856 (struct sk_buff *skb, struct ip_vs_conn *cp, struct ip_vs_protocol *pp);
857 extern int ip_vs_nat_xmit
858 (struct sk_buff *skb, struct ip_vs_conn *cp, struct ip_vs_protocol *pp);
859 extern int ip_vs_tunnel_xmit
860 (struct sk_buff *skb, struct ip_vs_conn *cp, struct ip_vs_protocol *pp);
861 extern int ip_vs_dr_xmit
862 (struct sk_buff *skb, struct ip_vs_conn *cp, struct ip_vs_protocol *pp);
863 extern int ip_vs_icmp_xmit
864 (struct sk_buff *skb, struct ip_vs_conn *cp, struct ip_vs_protocol *pp, int offset);
865 extern void ip_vs_dst_reset(struct ip_vs_dest *dest);
866 
867 #ifdef CONFIG_IP_VS_IPV6
868 extern int ip_vs_bypass_xmit_v6
869 (struct sk_buff *skb, struct ip_vs_conn *cp, struct ip_vs_protocol *pp);
870 extern int ip_vs_nat_xmit_v6
871 (struct sk_buff *skb, struct ip_vs_conn *cp, struct ip_vs_protocol *pp);
872 extern int ip_vs_tunnel_xmit_v6
873 (struct sk_buff *skb, struct ip_vs_conn *cp, struct ip_vs_protocol *pp);
874 extern int ip_vs_dr_xmit_v6
875 (struct sk_buff *skb, struct ip_vs_conn *cp, struct ip_vs_protocol *pp);
876 extern int ip_vs_icmp_xmit_v6
877 (struct sk_buff *skb, struct ip_vs_conn *cp, struct ip_vs_protocol *pp,
878  int offset);
879 #endif
880 
881 /*
882  *	This is a simple mechanism to ignore packets when
883  *	we are loaded. Just set ip_vs_drop_rate to 'n' and
884  *	we start to drop 1/rate of the packets
885  */
886 extern int ip_vs_drop_rate;
887 extern int ip_vs_drop_counter;
888 
889 static __inline__ int ip_vs_todrop(void)
890 {
891 	if (!ip_vs_drop_rate) return 0;
892 	if (--ip_vs_drop_counter > 0) return 0;
893 	ip_vs_drop_counter = ip_vs_drop_rate;
894 	return 1;
895 }
896 
897 /*
898  *      ip_vs_fwd_tag returns the forwarding tag of the connection
899  */
900 #define IP_VS_FWD_METHOD(cp)  (cp->flags & IP_VS_CONN_F_FWD_MASK)
901 
902 static inline char ip_vs_fwd_tag(struct ip_vs_conn *cp)
903 {
904 	char fwd;
905 
906 	switch (IP_VS_FWD_METHOD(cp)) {
907 	case IP_VS_CONN_F_MASQ:
908 		fwd = 'M'; break;
909 	case IP_VS_CONN_F_LOCALNODE:
910 		fwd = 'L'; break;
911 	case IP_VS_CONN_F_TUNNEL:
912 		fwd = 'T'; break;
913 	case IP_VS_CONN_F_DROUTE:
914 		fwd = 'R'; break;
915 	case IP_VS_CONN_F_BYPASS:
916 		fwd = 'B'; break;
917 	default:
918 		fwd = '?'; break;
919 	}
920 	return fwd;
921 }
922 
923 extern void ip_vs_nat_icmp(struct sk_buff *skb, struct ip_vs_protocol *pp,
924 			   struct ip_vs_conn *cp, int dir);
925 
926 #ifdef CONFIG_IP_VS_IPV6
927 extern void ip_vs_nat_icmp_v6(struct sk_buff *skb, struct ip_vs_protocol *pp,
928 			      struct ip_vs_conn *cp, int dir);
929 #endif
930 
931 extern __sum16 ip_vs_checksum_complete(struct sk_buff *skb, int offset);
932 
933 static inline __wsum ip_vs_check_diff4(__be32 old, __be32 new, __wsum oldsum)
934 {
935 	__be32 diff[2] = { ~old, new };
936 
937 	return csum_partial(diff, sizeof(diff), oldsum);
938 }
939 
940 #ifdef CONFIG_IP_VS_IPV6
941 static inline __wsum ip_vs_check_diff16(const __be32 *old, const __be32 *new,
942 					__wsum oldsum)
943 {
944 	__be32 diff[8] = { ~old[3], ~old[2], ~old[1], ~old[0],
945 			    new[3],  new[2],  new[1],  new[0] };
946 
947 	return csum_partial(diff, sizeof(diff), oldsum);
948 }
949 #endif
950 
951 static inline __wsum ip_vs_check_diff2(__be16 old, __be16 new, __wsum oldsum)
952 {
953 	__be16 diff[2] = { ~old, new };
954 
955 	return csum_partial(diff, sizeof(diff), oldsum);
956 }
957 
958 #endif /* __KERNEL__ */
959 
960 #endif	/* _NET_IP_VS_H */
961