xref: /openbmc/linux/include/net/ip_vs.h (revision d2ba09c1)
1 /* SPDX-License-Identifier: GPL-2.0 */
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/refcount.h>             /* for struct refcount_t */
17 
18 #include <linux/compiler.h>
19 #include <linux/timer.h>
20 #include <linux/bug.h>
21 
22 #include <net/checksum.h>
23 #include <linux/netfilter.h>		/* for union nf_inet_addr */
24 #include <linux/ip.h>
25 #include <linux/ipv6.h>			/* for struct ipv6hdr */
26 #include <net/ipv6.h>
27 #if IS_ENABLED(CONFIG_IP_VS_IPV6)
28 #include <linux/netfilter_ipv6/ip6_tables.h>
29 #endif
30 #if IS_ENABLED(CONFIG_NF_CONNTRACK)
31 #include <net/netfilter/nf_conntrack.h>
32 #endif
33 #include <net/net_namespace.h>		/* Netw namespace */
34 
35 #define IP_VS_HDR_INVERSE	1
36 #define IP_VS_HDR_ICMP		2
37 
38 /* Generic access of ipvs struct */
39 static inline struct netns_ipvs *net_ipvs(struct net* net)
40 {
41 	return net->ipvs;
42 }
43 
44 /* This one needed for single_open_net since net is stored directly in
45  * private not as a struct i.e. seq_file_net can't be used.
46  */
47 static inline struct net *seq_file_single_net(struct seq_file *seq)
48 {
49 #ifdef CONFIG_NET_NS
50 	return (struct net *)seq->private;
51 #else
52 	return &init_net;
53 #endif
54 }
55 
56 /* Connections' size value needed by ip_vs_ctl.c */
57 extern int ip_vs_conn_tab_size;
58 
59 struct ip_vs_iphdr {
60 	int hdr_flags;	/* ipvs flags */
61 	__u32 off;	/* Where IP or IPv4 header starts */
62 	__u32 len;	/* IPv4 simply where L4 starts
63 			 * IPv6 where L4 Transport Header starts */
64 	__u16 fragoffs; /* IPv6 fragment offset, 0 if first frag (or not frag)*/
65 	__s16 protocol;
66 	__s32 flags;
67 	union nf_inet_addr saddr;
68 	union nf_inet_addr daddr;
69 };
70 
71 static inline void *frag_safe_skb_hp(const struct sk_buff *skb, int offset,
72 				      int len, void *buffer)
73 {
74 	return skb_header_pointer(skb, offset, len, buffer);
75 }
76 
77 /* This function handles filling *ip_vs_iphdr, both for IPv4 and IPv6.
78  * IPv6 requires some extra work, as finding proper header position,
79  * depend on the IPv6 extension headers.
80  */
81 static inline int
82 ip_vs_fill_iph_skb_off(int af, const struct sk_buff *skb, int offset,
83 		       int hdr_flags, struct ip_vs_iphdr *iphdr)
84 {
85 	iphdr->hdr_flags = hdr_flags;
86 	iphdr->off = offset;
87 
88 #ifdef CONFIG_IP_VS_IPV6
89 	if (af == AF_INET6) {
90 		struct ipv6hdr _iph;
91 		const struct ipv6hdr *iph = skb_header_pointer(
92 			skb, offset, sizeof(_iph), &_iph);
93 		if (!iph)
94 			return 0;
95 
96 		iphdr->saddr.in6 = iph->saddr;
97 		iphdr->daddr.in6 = iph->daddr;
98 		/* ipv6_find_hdr() updates len, flags */
99 		iphdr->len	 = offset;
100 		iphdr->flags	 = 0;
101 		iphdr->protocol  = ipv6_find_hdr(skb, &iphdr->len, -1,
102 						 &iphdr->fragoffs,
103 						 &iphdr->flags);
104 		if (iphdr->protocol < 0)
105 			return 0;
106 	} else
107 #endif
108 	{
109 		struct iphdr _iph;
110 		const struct iphdr *iph = skb_header_pointer(
111 			skb, offset, sizeof(_iph), &_iph);
112 		if (!iph)
113 			return 0;
114 
115 		iphdr->len	= offset + iph->ihl * 4;
116 		iphdr->fragoffs	= 0;
117 		iphdr->protocol	= iph->protocol;
118 		iphdr->saddr.ip	= iph->saddr;
119 		iphdr->daddr.ip	= iph->daddr;
120 	}
121 
122 	return 1;
123 }
124 
125 static inline int
126 ip_vs_fill_iph_skb_icmp(int af, const struct sk_buff *skb, int offset,
127 			bool inverse, struct ip_vs_iphdr *iphdr)
128 {
129 	int hdr_flags = IP_VS_HDR_ICMP;
130 
131 	if (inverse)
132 		hdr_flags |= IP_VS_HDR_INVERSE;
133 
134 	return ip_vs_fill_iph_skb_off(af, skb, offset, hdr_flags, iphdr);
135 }
136 
137 static inline int
138 ip_vs_fill_iph_skb(int af, const struct sk_buff *skb, bool inverse,
139 		   struct ip_vs_iphdr *iphdr)
140 {
141 	int hdr_flags = 0;
142 
143 	if (inverse)
144 		hdr_flags |= IP_VS_HDR_INVERSE;
145 
146 	return ip_vs_fill_iph_skb_off(af, skb, skb_network_offset(skb),
147 				      hdr_flags, iphdr);
148 }
149 
150 static inline bool
151 ip_vs_iph_inverse(const struct ip_vs_iphdr *iph)
152 {
153 	return !!(iph->hdr_flags & IP_VS_HDR_INVERSE);
154 }
155 
156 static inline bool
157 ip_vs_iph_icmp(const struct ip_vs_iphdr *iph)
158 {
159 	return !!(iph->hdr_flags & IP_VS_HDR_ICMP);
160 }
161 
162 static inline void ip_vs_addr_copy(int af, union nf_inet_addr *dst,
163 				   const union nf_inet_addr *src)
164 {
165 #ifdef CONFIG_IP_VS_IPV6
166 	if (af == AF_INET6)
167 		dst->in6 = src->in6;
168 	else
169 #endif
170 	dst->ip = src->ip;
171 }
172 
173 static inline void ip_vs_addr_set(int af, union nf_inet_addr *dst,
174 				  const union nf_inet_addr *src)
175 {
176 #ifdef CONFIG_IP_VS_IPV6
177 	if (af == AF_INET6) {
178 		dst->in6 = src->in6;
179 		return;
180 	}
181 #endif
182 	dst->ip = src->ip;
183 	dst->all[1] = 0;
184 	dst->all[2] = 0;
185 	dst->all[3] = 0;
186 }
187 
188 static inline int ip_vs_addr_equal(int af, const union nf_inet_addr *a,
189 				   const union nf_inet_addr *b)
190 {
191 #ifdef CONFIG_IP_VS_IPV6
192 	if (af == AF_INET6)
193 		return ipv6_addr_equal(&a->in6, &b->in6);
194 #endif
195 	return a->ip == b->ip;
196 }
197 
198 #ifdef CONFIG_IP_VS_DEBUG
199 #include <linux/net.h>
200 
201 int ip_vs_get_debug_level(void);
202 
203 static inline const char *ip_vs_dbg_addr(int af, char *buf, size_t buf_len,
204 					 const union nf_inet_addr *addr,
205 					 int *idx)
206 {
207 	int len;
208 #ifdef CONFIG_IP_VS_IPV6
209 	if (af == AF_INET6)
210 		len = snprintf(&buf[*idx], buf_len - *idx, "[%pI6c]",
211 			       &addr->in6) + 1;
212 	else
213 #endif
214 		len = snprintf(&buf[*idx], buf_len - *idx, "%pI4",
215 			       &addr->ip) + 1;
216 
217 	*idx += len;
218 	BUG_ON(*idx > buf_len + 1);
219 	return &buf[*idx - len];
220 }
221 
222 #define IP_VS_DBG_BUF(level, msg, ...)					\
223 	do {								\
224 		char ip_vs_dbg_buf[160];				\
225 		int ip_vs_dbg_idx = 0;					\
226 		if (level <= ip_vs_get_debug_level())			\
227 			printk(KERN_DEBUG pr_fmt(msg), ##__VA_ARGS__);	\
228 	} while (0)
229 #define IP_VS_ERR_BUF(msg...)						\
230 	do {								\
231 		char ip_vs_dbg_buf[160];				\
232 		int ip_vs_dbg_idx = 0;					\
233 		pr_err(msg);						\
234 	} while (0)
235 
236 /* Only use from within IP_VS_DBG_BUF() or IP_VS_ERR_BUF macros */
237 #define IP_VS_DBG_ADDR(af, addr)					\
238 	ip_vs_dbg_addr(af, ip_vs_dbg_buf,				\
239 		       sizeof(ip_vs_dbg_buf), addr,			\
240 		       &ip_vs_dbg_idx)
241 
242 #define IP_VS_DBG(level, msg, ...)					\
243 	do {								\
244 		if (level <= ip_vs_get_debug_level())			\
245 			printk(KERN_DEBUG pr_fmt(msg), ##__VA_ARGS__);	\
246 	} while (0)
247 #define IP_VS_DBG_RL(msg, ...)						\
248 	do {								\
249 		if (net_ratelimit())					\
250 			printk(KERN_DEBUG pr_fmt(msg), ##__VA_ARGS__);	\
251 	} while (0)
252 #define IP_VS_DBG_PKT(level, af, pp, skb, ofs, msg)			\
253 	do {								\
254 		if (level <= ip_vs_get_debug_level())			\
255 			pp->debug_packet(af, pp, skb, ofs, msg);	\
256 	} while (0)
257 #define IP_VS_DBG_RL_PKT(level, af, pp, skb, ofs, msg)			\
258 	do {								\
259 		if (level <= ip_vs_get_debug_level() &&			\
260 		    net_ratelimit())					\
261 			pp->debug_packet(af, pp, skb, ofs, msg);	\
262 	} while (0)
263 #else	/* NO DEBUGGING at ALL */
264 #define IP_VS_DBG_BUF(level, msg...)  do {} while (0)
265 #define IP_VS_ERR_BUF(msg...)  do {} while (0)
266 #define IP_VS_DBG(level, msg...)  do {} while (0)
267 #define IP_VS_DBG_RL(msg...)  do {} while (0)
268 #define IP_VS_DBG_PKT(level, af, pp, skb, ofs, msg)	do {} while (0)
269 #define IP_VS_DBG_RL_PKT(level, af, pp, skb, ofs, msg)	do {} while (0)
270 #endif
271 
272 #define IP_VS_BUG() BUG()
273 #define IP_VS_ERR_RL(msg, ...)						\
274 	do {								\
275 		if (net_ratelimit())					\
276 			pr_err(msg, ##__VA_ARGS__);			\
277 	} while (0)
278 
279 #ifdef CONFIG_IP_VS_DEBUG
280 #define EnterFunction(level)						\
281 	do {								\
282 		if (level <= ip_vs_get_debug_level())			\
283 			printk(KERN_DEBUG				\
284 			       pr_fmt("Enter: %s, %s line %i\n"),	\
285 			       __func__, __FILE__, __LINE__);		\
286 	} while (0)
287 #define LeaveFunction(level)						\
288 	do {								\
289 		if (level <= ip_vs_get_debug_level())			\
290 			printk(KERN_DEBUG				\
291 			       pr_fmt("Leave: %s, %s line %i\n"),	\
292 			       __func__, __FILE__, __LINE__);		\
293 	} while (0)
294 #else
295 #define EnterFunction(level)   do {} while (0)
296 #define LeaveFunction(level)   do {} while (0)
297 #endif
298 
299 /* The port number of FTP service (in network order). */
300 #define FTPPORT  cpu_to_be16(21)
301 #define FTPDATA  cpu_to_be16(20)
302 
303 /* TCP State Values */
304 enum {
305 	IP_VS_TCP_S_NONE = 0,
306 	IP_VS_TCP_S_ESTABLISHED,
307 	IP_VS_TCP_S_SYN_SENT,
308 	IP_VS_TCP_S_SYN_RECV,
309 	IP_VS_TCP_S_FIN_WAIT,
310 	IP_VS_TCP_S_TIME_WAIT,
311 	IP_VS_TCP_S_CLOSE,
312 	IP_VS_TCP_S_CLOSE_WAIT,
313 	IP_VS_TCP_S_LAST_ACK,
314 	IP_VS_TCP_S_LISTEN,
315 	IP_VS_TCP_S_SYNACK,
316 	IP_VS_TCP_S_LAST
317 };
318 
319 /* UDP State Values */
320 enum {
321 	IP_VS_UDP_S_NORMAL,
322 	IP_VS_UDP_S_LAST,
323 };
324 
325 /* ICMP State Values */
326 enum {
327 	IP_VS_ICMP_S_NORMAL,
328 	IP_VS_ICMP_S_LAST,
329 };
330 
331 /* SCTP State Values */
332 enum ip_vs_sctp_states {
333 	IP_VS_SCTP_S_NONE,
334 	IP_VS_SCTP_S_INIT1,
335 	IP_VS_SCTP_S_INIT,
336 	IP_VS_SCTP_S_COOKIE_SENT,
337 	IP_VS_SCTP_S_COOKIE_REPLIED,
338 	IP_VS_SCTP_S_COOKIE_WAIT,
339 	IP_VS_SCTP_S_COOKIE,
340 	IP_VS_SCTP_S_COOKIE_ECHOED,
341 	IP_VS_SCTP_S_ESTABLISHED,
342 	IP_VS_SCTP_S_SHUTDOWN_SENT,
343 	IP_VS_SCTP_S_SHUTDOWN_RECEIVED,
344 	IP_VS_SCTP_S_SHUTDOWN_ACK_SENT,
345 	IP_VS_SCTP_S_REJECTED,
346 	IP_VS_SCTP_S_CLOSED,
347 	IP_VS_SCTP_S_LAST
348 };
349 
350 /* Delta sequence info structure
351  * Each ip_vs_conn has 2 (output AND input seq. changes).
352  * Only used in the VS/NAT.
353  */
354 struct ip_vs_seq {
355 	__u32			init_seq;	/* Add delta from this seq */
356 	__u32			delta;		/* Delta in sequence numbers */
357 	__u32			previous_delta;	/* Delta in sequence numbers
358 						 * before last resized pkt */
359 };
360 
361 /* counters per cpu */
362 struct ip_vs_counters {
363 	__u64		conns;		/* connections scheduled */
364 	__u64		inpkts;		/* incoming packets */
365 	__u64		outpkts;	/* outgoing packets */
366 	__u64		inbytes;	/* incoming bytes */
367 	__u64		outbytes;	/* outgoing bytes */
368 };
369 /* Stats per cpu */
370 struct ip_vs_cpu_stats {
371 	struct ip_vs_counters   cnt;
372 	struct u64_stats_sync   syncp;
373 };
374 
375 /* IPVS statistics objects */
376 struct ip_vs_estimator {
377 	struct list_head	list;
378 
379 	u64			last_inbytes;
380 	u64			last_outbytes;
381 	u64			last_conns;
382 	u64			last_inpkts;
383 	u64			last_outpkts;
384 
385 	u64			cps;
386 	u64			inpps;
387 	u64			outpps;
388 	u64			inbps;
389 	u64			outbps;
390 };
391 
392 /*
393  * IPVS statistics object, 64-bit kernel version of struct ip_vs_stats_user
394  */
395 struct ip_vs_kstats {
396 	u64			conns;		/* connections scheduled */
397 	u64			inpkts;		/* incoming packets */
398 	u64			outpkts;	/* outgoing packets */
399 	u64			inbytes;	/* incoming bytes */
400 	u64			outbytes;	/* outgoing bytes */
401 
402 	u64			cps;		/* current connection rate */
403 	u64			inpps;		/* current in packet rate */
404 	u64			outpps;		/* current out packet rate */
405 	u64			inbps;		/* current in byte rate */
406 	u64			outbps;		/* current out byte rate */
407 };
408 
409 struct ip_vs_stats {
410 	struct ip_vs_kstats	kstats;		/* kernel statistics */
411 	struct ip_vs_estimator	est;		/* estimator */
412 	struct ip_vs_cpu_stats __percpu	*cpustats;	/* per cpu counters */
413 	spinlock_t		lock;		/* spin lock */
414 	struct ip_vs_kstats	kstats0;	/* reset values */
415 };
416 
417 struct dst_entry;
418 struct iphdr;
419 struct ip_vs_conn;
420 struct ip_vs_app;
421 struct sk_buff;
422 struct ip_vs_proto_data;
423 
424 struct ip_vs_protocol {
425 	struct ip_vs_protocol	*next;
426 	char			*name;
427 	u16			protocol;
428 	u16			num_states;
429 	int			dont_defrag;
430 
431 	void (*init)(struct ip_vs_protocol *pp);
432 
433 	void (*exit)(struct ip_vs_protocol *pp);
434 
435 	int (*init_netns)(struct netns_ipvs *ipvs, struct ip_vs_proto_data *pd);
436 
437 	void (*exit_netns)(struct netns_ipvs *ipvs, struct ip_vs_proto_data *pd);
438 
439 	int (*conn_schedule)(struct netns_ipvs *ipvs,
440 			     int af, struct sk_buff *skb,
441 			     struct ip_vs_proto_data *pd,
442 			     int *verdict, struct ip_vs_conn **cpp,
443 			     struct ip_vs_iphdr *iph);
444 
445 	struct ip_vs_conn *
446 	(*conn_in_get)(struct netns_ipvs *ipvs,
447 		       int af,
448 		       const struct sk_buff *skb,
449 		       const struct ip_vs_iphdr *iph);
450 
451 	struct ip_vs_conn *
452 	(*conn_out_get)(struct netns_ipvs *ipvs,
453 			int af,
454 			const struct sk_buff *skb,
455 			const struct ip_vs_iphdr *iph);
456 
457 	int (*snat_handler)(struct sk_buff *skb, struct ip_vs_protocol *pp,
458 			    struct ip_vs_conn *cp, struct ip_vs_iphdr *iph);
459 
460 	int (*dnat_handler)(struct sk_buff *skb, struct ip_vs_protocol *pp,
461 			    struct ip_vs_conn *cp, struct ip_vs_iphdr *iph);
462 
463 	int (*csum_check)(int af, struct sk_buff *skb,
464 			  struct ip_vs_protocol *pp);
465 
466 	const char *(*state_name)(int state);
467 
468 	void (*state_transition)(struct ip_vs_conn *cp, int direction,
469 				 const struct sk_buff *skb,
470 				 struct ip_vs_proto_data *pd);
471 
472 	int (*register_app)(struct netns_ipvs *ipvs, struct ip_vs_app *inc);
473 
474 	void (*unregister_app)(struct netns_ipvs *ipvs, struct ip_vs_app *inc);
475 
476 	int (*app_conn_bind)(struct ip_vs_conn *cp);
477 
478 	void (*debug_packet)(int af, struct ip_vs_protocol *pp,
479 			     const struct sk_buff *skb,
480 			     int offset,
481 			     const char *msg);
482 
483 	void (*timeout_change)(struct ip_vs_proto_data *pd, int flags);
484 };
485 
486 /* protocol data per netns */
487 struct ip_vs_proto_data {
488 	struct ip_vs_proto_data	*next;
489 	struct ip_vs_protocol	*pp;
490 	int			*timeout_table;	/* protocol timeout table */
491 	atomic_t		appcnt;		/* counter of proto app incs. */
492 	struct tcp_states_t	*tcp_state_table;
493 };
494 
495 struct ip_vs_protocol   *ip_vs_proto_get(unsigned short proto);
496 struct ip_vs_proto_data *ip_vs_proto_data_get(struct netns_ipvs *ipvs,
497 					      unsigned short proto);
498 
499 struct ip_vs_conn_param {
500 	struct netns_ipvs		*ipvs;
501 	const union nf_inet_addr	*caddr;
502 	const union nf_inet_addr	*vaddr;
503 	__be16				cport;
504 	__be16				vport;
505 	__u16				protocol;
506 	u16				af;
507 
508 	const struct ip_vs_pe		*pe;
509 	char				*pe_data;
510 	__u8				pe_data_len;
511 };
512 
513 /* IP_VS structure allocated for each dynamically scheduled connection */
514 struct ip_vs_conn {
515 	struct hlist_node	c_list;         /* hashed list heads */
516 	/* Protocol, addresses and port numbers */
517 	__be16                  cport;
518 	__be16                  dport;
519 	__be16                  vport;
520 	u16			af;		/* address family */
521 	union nf_inet_addr      caddr;          /* client address */
522 	union nf_inet_addr      vaddr;          /* virtual address */
523 	union nf_inet_addr      daddr;          /* destination address */
524 	volatile __u32          flags;          /* status flags */
525 	__u16                   protocol;       /* Which protocol (TCP/UDP) */
526 	__u16			daf;		/* Address family of the dest */
527 	struct netns_ipvs	*ipvs;
528 
529 	/* counter and timer */
530 	refcount_t		refcnt;		/* reference count */
531 	struct timer_list	timer;		/* Expiration timer */
532 	volatile unsigned long	timeout;	/* timeout */
533 
534 	/* Flags and state transition */
535 	spinlock_t              lock;           /* lock for state transition */
536 	volatile __u16          state;          /* state info */
537 	volatile __u16          old_state;      /* old state, to be used for
538 						 * state transition triggerd
539 						 * synchronization
540 						 */
541 	__u32			fwmark;		/* Fire wall mark from skb */
542 	unsigned long		sync_endtime;	/* jiffies + sent_retries */
543 
544 	/* Control members */
545 	struct ip_vs_conn       *control;       /* Master control connection */
546 	atomic_t                n_control;      /* Number of controlled ones */
547 	struct ip_vs_dest       *dest;          /* real server */
548 	atomic_t                in_pkts;        /* incoming packet counter */
549 
550 	/* Packet transmitter for different forwarding methods.  If it
551 	 * mangles the packet, it must return NF_DROP or better NF_STOLEN,
552 	 * otherwise this must be changed to a sk_buff **.
553 	 * NF_ACCEPT can be returned when destination is local.
554 	 */
555 	int (*packet_xmit)(struct sk_buff *skb, struct ip_vs_conn *cp,
556 			   struct ip_vs_protocol *pp, struct ip_vs_iphdr *iph);
557 
558 	/* Note: we can group the following members into a structure,
559 	 * in order to save more space, and the following members are
560 	 * only used in VS/NAT anyway
561 	 */
562 	struct ip_vs_app        *app;           /* bound ip_vs_app object */
563 	void                    *app_data;      /* Application private data */
564 	struct ip_vs_seq        in_seq;         /* incoming seq. struct */
565 	struct ip_vs_seq        out_seq;        /* outgoing seq. struct */
566 
567 	const struct ip_vs_pe	*pe;
568 	char			*pe_data;
569 	__u8			pe_data_len;
570 
571 	struct rcu_head		rcu_head;
572 };
573 
574 /* Extended internal versions of struct ip_vs_service_user and ip_vs_dest_user
575  * for IPv6 support.
576  *
577  * We need these to conveniently pass around service and destination
578  * options, but unfortunately, we also need to keep the old definitions to
579  * maintain userspace backwards compatibility for the setsockopt interface.
580  */
581 struct ip_vs_service_user_kern {
582 	/* virtual service addresses */
583 	u16			af;
584 	u16			protocol;
585 	union nf_inet_addr	addr;		/* virtual ip address */
586 	__be16			port;
587 	u32			fwmark;		/* firwall mark of service */
588 
589 	/* virtual service options */
590 	char			*sched_name;
591 	char			*pe_name;
592 	unsigned int		flags;		/* virtual service flags */
593 	unsigned int		timeout;	/* persistent timeout in sec */
594 	__be32			netmask;	/* persistent netmask or plen */
595 };
596 
597 
598 struct ip_vs_dest_user_kern {
599 	/* destination server address */
600 	union nf_inet_addr	addr;
601 	__be16			port;
602 
603 	/* real server options */
604 	unsigned int		conn_flags;	/* connection flags */
605 	int			weight;		/* destination weight */
606 
607 	/* thresholds for active connections */
608 	u32			u_threshold;	/* upper threshold */
609 	u32			l_threshold;	/* lower threshold */
610 
611 	/* Address family of addr */
612 	u16			af;
613 };
614 
615 
616 /*
617  * The information about the virtual service offered to the net and the
618  * forwarding entries.
619  */
620 struct ip_vs_service {
621 	struct hlist_node	s_list;   /* for normal service table */
622 	struct hlist_node	f_list;   /* for fwmark-based service table */
623 	atomic_t		refcnt;   /* reference counter */
624 
625 	u16			af;       /* address family */
626 	__u16			protocol; /* which protocol (TCP/UDP) */
627 	union nf_inet_addr	addr;	  /* IP address for virtual service */
628 	__be16			port;	  /* port number for the service */
629 	__u32                   fwmark;   /* firewall mark of the service */
630 	unsigned int		flags;	  /* service status flags */
631 	unsigned int		timeout;  /* persistent timeout in ticks */
632 	__be32			netmask;  /* grouping granularity, mask/plen */
633 	struct netns_ipvs	*ipvs;
634 
635 	struct list_head	destinations;  /* real server d-linked list */
636 	__u32			num_dests;     /* number of servers */
637 	struct ip_vs_stats      stats;         /* statistics for the service */
638 
639 	/* for scheduling */
640 	struct ip_vs_scheduler __rcu *scheduler; /* bound scheduler object */
641 	spinlock_t		sched_lock;    /* lock sched_data */
642 	void			*sched_data;   /* scheduler application data */
643 
644 	/* alternate persistence engine */
645 	struct ip_vs_pe __rcu	*pe;
646 
647 	struct rcu_head		rcu_head;
648 };
649 
650 /* Information for cached dst */
651 struct ip_vs_dest_dst {
652 	struct dst_entry	*dst_cache;	/* destination cache entry */
653 	u32			dst_cookie;
654 	union nf_inet_addr	dst_saddr;
655 	struct rcu_head		rcu_head;
656 };
657 
658 /* The real server destination forwarding entry with ip address, port number,
659  * and so on.
660  */
661 struct ip_vs_dest {
662 	struct list_head	n_list;   /* for the dests in the service */
663 	struct hlist_node	d_list;   /* for table with all the dests */
664 
665 	u16			af;		/* address family */
666 	__be16			port;		/* port number of the server */
667 	union nf_inet_addr	addr;		/* IP address of the server */
668 	volatile unsigned int	flags;		/* dest status flags */
669 	atomic_t		conn_flags;	/* flags to copy to conn */
670 	atomic_t		weight;		/* server weight */
671 	atomic_t		last_weight;	/* server latest weight */
672 
673 	refcount_t		refcnt;		/* reference counter */
674 	struct ip_vs_stats      stats;          /* statistics */
675 	unsigned long		idle_start;	/* start time, jiffies */
676 
677 	/* connection counters and thresholds */
678 	atomic_t		activeconns;	/* active connections */
679 	atomic_t		inactconns;	/* inactive connections */
680 	atomic_t		persistconns;	/* persistent connections */
681 	__u32			u_threshold;	/* upper threshold */
682 	__u32			l_threshold;	/* lower threshold */
683 
684 	/* for destination cache */
685 	spinlock_t		dst_lock;	/* lock of dst_cache */
686 	struct ip_vs_dest_dst __rcu *dest_dst;	/* cached dst info */
687 
688 	/* for virtual service */
689 	struct ip_vs_service __rcu *svc;	/* service it belongs to */
690 	__u16			protocol;	/* which protocol (TCP/UDP) */
691 	__be16			vport;		/* virtual port number */
692 	union nf_inet_addr	vaddr;		/* virtual IP address */
693 	__u32			vfwmark;	/* firewall mark of service */
694 
695 	struct list_head	t_list;		/* in dest_trash */
696 	unsigned int		in_rs_table:1;	/* we are in rs_table */
697 };
698 
699 /* The scheduler object */
700 struct ip_vs_scheduler {
701 	struct list_head	n_list;		/* d-linked list head */
702 	char			*name;		/* scheduler name */
703 	atomic_t		refcnt;		/* reference counter */
704 	struct module		*module;	/* THIS_MODULE/NULL */
705 
706 	/* scheduler initializing service */
707 	int (*init_service)(struct ip_vs_service *svc);
708 	/* scheduling service finish */
709 	void (*done_service)(struct ip_vs_service *svc);
710 	/* dest is linked */
711 	int (*add_dest)(struct ip_vs_service *svc, struct ip_vs_dest *dest);
712 	/* dest is unlinked */
713 	int (*del_dest)(struct ip_vs_service *svc, struct ip_vs_dest *dest);
714 	/* dest is updated */
715 	int (*upd_dest)(struct ip_vs_service *svc, struct ip_vs_dest *dest);
716 
717 	/* selecting a server from the given service */
718 	struct ip_vs_dest* (*schedule)(struct ip_vs_service *svc,
719 				       const struct sk_buff *skb,
720 				       struct ip_vs_iphdr *iph);
721 };
722 
723 /* The persistence engine object */
724 struct ip_vs_pe {
725 	struct list_head	n_list;		/* d-linked list head */
726 	char			*name;		/* scheduler name */
727 	atomic_t		refcnt;		/* reference counter */
728 	struct module		*module;	/* THIS_MODULE/NULL */
729 
730 	/* get the connection template, if any */
731 	int (*fill_param)(struct ip_vs_conn_param *p, struct sk_buff *skb);
732 	bool (*ct_match)(const struct ip_vs_conn_param *p,
733 			 struct ip_vs_conn *ct);
734 	u32 (*hashkey_raw)(const struct ip_vs_conn_param *p, u32 initval,
735 			   bool inverse);
736 	int (*show_pe_data)(const struct ip_vs_conn *cp, char *buf);
737 	/* create connections for real-server outgoing packets */
738 	struct ip_vs_conn* (*conn_out)(struct ip_vs_service *svc,
739 				       struct ip_vs_dest *dest,
740 				       struct sk_buff *skb,
741 				       const struct ip_vs_iphdr *iph,
742 				       __be16 dport, __be16 cport);
743 };
744 
745 /* The application module object (a.k.a. app incarnation) */
746 struct ip_vs_app {
747 	struct list_head	a_list;		/* member in app list */
748 	int			type;		/* IP_VS_APP_TYPE_xxx */
749 	char			*name;		/* application module name */
750 	__u16			protocol;
751 	struct module		*module;	/* THIS_MODULE/NULL */
752 	struct list_head	incs_list;	/* list of incarnations */
753 
754 	/* members for application incarnations */
755 	struct list_head	p_list;		/* member in proto app list */
756 	struct ip_vs_app	*app;		/* its real application */
757 	__be16			port;		/* port number in net order */
758 	atomic_t		usecnt;		/* usage counter */
759 	struct rcu_head		rcu_head;
760 
761 	/* output hook: Process packet in inout direction, diff set for TCP.
762 	 * Return: 0=Error, 1=Payload Not Mangled/Mangled but checksum is ok,
763 	 *	   2=Mangled but checksum was not updated
764 	 */
765 	int (*pkt_out)(struct ip_vs_app *, struct ip_vs_conn *,
766 		       struct sk_buff *, int *diff);
767 
768 	/* input hook: Process packet in outin direction, diff set for TCP.
769 	 * Return: 0=Error, 1=Payload Not Mangled/Mangled but checksum is ok,
770 	 *	   2=Mangled but checksum was not updated
771 	 */
772 	int (*pkt_in)(struct ip_vs_app *, struct ip_vs_conn *,
773 		      struct sk_buff *, int *diff);
774 
775 	/* ip_vs_app initializer */
776 	int (*init_conn)(struct ip_vs_app *, struct ip_vs_conn *);
777 
778 	/* ip_vs_app finish */
779 	int (*done_conn)(struct ip_vs_app *, struct ip_vs_conn *);
780 
781 
782 	/* not used now */
783 	int (*bind_conn)(struct ip_vs_app *, struct ip_vs_conn *,
784 			 struct ip_vs_protocol *);
785 
786 	void (*unbind_conn)(struct ip_vs_app *, struct ip_vs_conn *);
787 
788 	int *			timeout_table;
789 	int *			timeouts;
790 	int			timeouts_size;
791 
792 	int (*conn_schedule)(struct sk_buff *skb, struct ip_vs_app *app,
793 			     int *verdict, struct ip_vs_conn **cpp);
794 
795 	struct ip_vs_conn *
796 	(*conn_in_get)(const struct sk_buff *skb, struct ip_vs_app *app,
797 		       const struct iphdr *iph, int inverse);
798 
799 	struct ip_vs_conn *
800 	(*conn_out_get)(const struct sk_buff *skb, struct ip_vs_app *app,
801 			const struct iphdr *iph, int inverse);
802 
803 	int (*state_transition)(struct ip_vs_conn *cp, int direction,
804 				const struct sk_buff *skb,
805 				struct ip_vs_app *app);
806 
807 	void (*timeout_change)(struct ip_vs_app *app, int flags);
808 };
809 
810 struct ipvs_master_sync_state {
811 	struct list_head	sync_queue;
812 	struct ip_vs_sync_buff	*sync_buff;
813 	unsigned long		sync_queue_len;
814 	unsigned int		sync_queue_delay;
815 	struct task_struct	*master_thread;
816 	struct delayed_work	master_wakeup_work;
817 	struct netns_ipvs	*ipvs;
818 };
819 
820 /* How much time to keep dests in trash */
821 #define IP_VS_DEST_TRASH_PERIOD		(120 * HZ)
822 
823 struct ipvs_sync_daemon_cfg {
824 	union nf_inet_addr	mcast_group;
825 	int			syncid;
826 	u16			sync_maxlen;
827 	u16			mcast_port;
828 	u8			mcast_af;
829 	u8			mcast_ttl;
830 	/* multicast interface name */
831 	char			mcast_ifn[IP_VS_IFNAME_MAXLEN];
832 };
833 
834 /* IPVS in network namespace */
835 struct netns_ipvs {
836 	int			gen;		/* Generation */
837 	int			enable;		/* enable like nf_hooks do */
838 	/* Hash table: for real service lookups */
839 	#define IP_VS_RTAB_BITS 4
840 	#define IP_VS_RTAB_SIZE (1 << IP_VS_RTAB_BITS)
841 	#define IP_VS_RTAB_MASK (IP_VS_RTAB_SIZE - 1)
842 
843 	struct hlist_head	rs_table[IP_VS_RTAB_SIZE];
844 	/* ip_vs_app */
845 	struct list_head	app_list;
846 	/* ip_vs_proto */
847 	#define IP_VS_PROTO_TAB_SIZE	32	/* must be power of 2 */
848 	struct ip_vs_proto_data *proto_data_table[IP_VS_PROTO_TAB_SIZE];
849 	/* ip_vs_proto_tcp */
850 #ifdef CONFIG_IP_VS_PROTO_TCP
851 	#define	TCP_APP_TAB_BITS	4
852 	#define	TCP_APP_TAB_SIZE	(1 << TCP_APP_TAB_BITS)
853 	#define	TCP_APP_TAB_MASK	(TCP_APP_TAB_SIZE - 1)
854 	struct list_head	tcp_apps[TCP_APP_TAB_SIZE];
855 #endif
856 	/* ip_vs_proto_udp */
857 #ifdef CONFIG_IP_VS_PROTO_UDP
858 	#define	UDP_APP_TAB_BITS	4
859 	#define	UDP_APP_TAB_SIZE	(1 << UDP_APP_TAB_BITS)
860 	#define	UDP_APP_TAB_MASK	(UDP_APP_TAB_SIZE - 1)
861 	struct list_head	udp_apps[UDP_APP_TAB_SIZE];
862 #endif
863 	/* ip_vs_proto_sctp */
864 #ifdef CONFIG_IP_VS_PROTO_SCTP
865 	#define SCTP_APP_TAB_BITS	4
866 	#define SCTP_APP_TAB_SIZE	(1 << SCTP_APP_TAB_BITS)
867 	#define SCTP_APP_TAB_MASK	(SCTP_APP_TAB_SIZE - 1)
868 	/* Hash table for SCTP application incarnations	 */
869 	struct list_head	sctp_apps[SCTP_APP_TAB_SIZE];
870 #endif
871 	/* ip_vs_conn */
872 	atomic_t		conn_count;      /* connection counter */
873 
874 	/* ip_vs_ctl */
875 	struct ip_vs_stats		tot_stats;  /* Statistics & est. */
876 
877 	int			num_services;    /* no of virtual services */
878 
879 	/* Trash for destinations */
880 	struct list_head	dest_trash;
881 	spinlock_t		dest_trash_lock;
882 	struct timer_list	dest_trash_timer; /* expiration timer */
883 	/* Service counters */
884 	atomic_t		ftpsvc_counter;
885 	atomic_t		nullsvc_counter;
886 	atomic_t		conn_out_counter;
887 
888 #ifdef CONFIG_SYSCTL
889 	/* 1/rate drop and drop-entry variables */
890 	struct delayed_work	defense_work;   /* Work handler */
891 	int			drop_rate;
892 	int			drop_counter;
893 	atomic_t		dropentry;
894 	/* locks in ctl.c */
895 	spinlock_t		dropentry_lock;  /* drop entry handling */
896 	spinlock_t		droppacket_lock; /* drop packet handling */
897 	spinlock_t		securetcp_lock;  /* state and timeout tables */
898 
899 	/* sys-ctl struct */
900 	struct ctl_table_header	*sysctl_hdr;
901 	struct ctl_table	*sysctl_tbl;
902 #endif
903 
904 	/* sysctl variables */
905 	int			sysctl_amemthresh;
906 	int			sysctl_am_droprate;
907 	int			sysctl_drop_entry;
908 	int			sysctl_drop_packet;
909 	int			sysctl_secure_tcp;
910 #ifdef CONFIG_IP_VS_NFCT
911 	int			sysctl_conntrack;
912 #endif
913 	int			sysctl_snat_reroute;
914 	int			sysctl_sync_ver;
915 	int			sysctl_sync_ports;
916 	int			sysctl_sync_persist_mode;
917 	unsigned long		sysctl_sync_qlen_max;
918 	int			sysctl_sync_sock_size;
919 	int			sysctl_cache_bypass;
920 	int			sysctl_expire_nodest_conn;
921 	int			sysctl_sloppy_tcp;
922 	int			sysctl_sloppy_sctp;
923 	int			sysctl_expire_quiescent_template;
924 	int			sysctl_sync_threshold[2];
925 	unsigned int		sysctl_sync_refresh_period;
926 	int			sysctl_sync_retries;
927 	int			sysctl_nat_icmp_send;
928 	int			sysctl_pmtu_disc;
929 	int			sysctl_backup_only;
930 	int			sysctl_conn_reuse_mode;
931 	int			sysctl_schedule_icmp;
932 	int			sysctl_ignore_tunneled;
933 
934 	/* ip_vs_lblc */
935 	int			sysctl_lblc_expiration;
936 	struct ctl_table_header	*lblc_ctl_header;
937 	struct ctl_table	*lblc_ctl_table;
938 	/* ip_vs_lblcr */
939 	int			sysctl_lblcr_expiration;
940 	struct ctl_table_header	*lblcr_ctl_header;
941 	struct ctl_table	*lblcr_ctl_table;
942 	/* ip_vs_est */
943 	struct list_head	est_list;	/* estimator list */
944 	spinlock_t		est_lock;
945 	struct timer_list	est_timer;	/* Estimation timer */
946 	/* ip_vs_sync */
947 	spinlock_t		sync_lock;
948 	struct ipvs_master_sync_state *ms;
949 	spinlock_t		sync_buff_lock;
950 	struct task_struct	**backup_threads;
951 	int			threads_mask;
952 	volatile int		sync_state;
953 	struct mutex		sync_mutex;
954 	struct ipvs_sync_daemon_cfg	mcfg;	/* Master Configuration */
955 	struct ipvs_sync_daemon_cfg	bcfg;	/* Backup Configuration */
956 	/* net name space ptr */
957 	struct net		*net;            /* Needed by timer routines */
958 	/* Number of heterogeneous destinations, needed becaus heterogeneous
959 	 * are not supported when synchronization is enabled.
960 	 */
961 	unsigned int		mixed_address_family_dests;
962 };
963 
964 #define DEFAULT_SYNC_THRESHOLD	3
965 #define DEFAULT_SYNC_PERIOD	50
966 #define DEFAULT_SYNC_VER	1
967 #define DEFAULT_SLOPPY_TCP	0
968 #define DEFAULT_SLOPPY_SCTP	0
969 #define DEFAULT_SYNC_REFRESH_PERIOD	(0U * HZ)
970 #define DEFAULT_SYNC_RETRIES		0
971 #define IPVS_SYNC_WAKEUP_RATE	8
972 #define IPVS_SYNC_QLEN_MAX	(IPVS_SYNC_WAKEUP_RATE * 4)
973 #define IPVS_SYNC_SEND_DELAY	(HZ / 50)
974 #define IPVS_SYNC_CHECK_PERIOD	HZ
975 #define IPVS_SYNC_FLUSH_TIME	(HZ * 2)
976 #define IPVS_SYNC_PORTS_MAX	(1 << 6)
977 
978 #ifdef CONFIG_SYSCTL
979 
980 static inline int sysctl_sync_threshold(struct netns_ipvs *ipvs)
981 {
982 	return ipvs->sysctl_sync_threshold[0];
983 }
984 
985 static inline int sysctl_sync_period(struct netns_ipvs *ipvs)
986 {
987 	return READ_ONCE(ipvs->sysctl_sync_threshold[1]);
988 }
989 
990 static inline unsigned int sysctl_sync_refresh_period(struct netns_ipvs *ipvs)
991 {
992 	return READ_ONCE(ipvs->sysctl_sync_refresh_period);
993 }
994 
995 static inline int sysctl_sync_retries(struct netns_ipvs *ipvs)
996 {
997 	return ipvs->sysctl_sync_retries;
998 }
999 
1000 static inline int sysctl_sync_ver(struct netns_ipvs *ipvs)
1001 {
1002 	return ipvs->sysctl_sync_ver;
1003 }
1004 
1005 static inline int sysctl_sloppy_tcp(struct netns_ipvs *ipvs)
1006 {
1007 	return ipvs->sysctl_sloppy_tcp;
1008 }
1009 
1010 static inline int sysctl_sloppy_sctp(struct netns_ipvs *ipvs)
1011 {
1012 	return ipvs->sysctl_sloppy_sctp;
1013 }
1014 
1015 static inline int sysctl_sync_ports(struct netns_ipvs *ipvs)
1016 {
1017 	return READ_ONCE(ipvs->sysctl_sync_ports);
1018 }
1019 
1020 static inline int sysctl_sync_persist_mode(struct netns_ipvs *ipvs)
1021 {
1022 	return ipvs->sysctl_sync_persist_mode;
1023 }
1024 
1025 static inline unsigned long sysctl_sync_qlen_max(struct netns_ipvs *ipvs)
1026 {
1027 	return ipvs->sysctl_sync_qlen_max;
1028 }
1029 
1030 static inline int sysctl_sync_sock_size(struct netns_ipvs *ipvs)
1031 {
1032 	return ipvs->sysctl_sync_sock_size;
1033 }
1034 
1035 static inline int sysctl_pmtu_disc(struct netns_ipvs *ipvs)
1036 {
1037 	return ipvs->sysctl_pmtu_disc;
1038 }
1039 
1040 static inline int sysctl_backup_only(struct netns_ipvs *ipvs)
1041 {
1042 	return ipvs->sync_state & IP_VS_STATE_BACKUP &&
1043 	       ipvs->sysctl_backup_only;
1044 }
1045 
1046 static inline int sysctl_conn_reuse_mode(struct netns_ipvs *ipvs)
1047 {
1048 	return ipvs->sysctl_conn_reuse_mode;
1049 }
1050 
1051 static inline int sysctl_schedule_icmp(struct netns_ipvs *ipvs)
1052 {
1053 	return ipvs->sysctl_schedule_icmp;
1054 }
1055 
1056 static inline int sysctl_ignore_tunneled(struct netns_ipvs *ipvs)
1057 {
1058 	return ipvs->sysctl_ignore_tunneled;
1059 }
1060 
1061 static inline int sysctl_cache_bypass(struct netns_ipvs *ipvs)
1062 {
1063 	return ipvs->sysctl_cache_bypass;
1064 }
1065 
1066 #else
1067 
1068 static inline int sysctl_sync_threshold(struct netns_ipvs *ipvs)
1069 {
1070 	return DEFAULT_SYNC_THRESHOLD;
1071 }
1072 
1073 static inline int sysctl_sync_period(struct netns_ipvs *ipvs)
1074 {
1075 	return DEFAULT_SYNC_PERIOD;
1076 }
1077 
1078 static inline unsigned int sysctl_sync_refresh_period(struct netns_ipvs *ipvs)
1079 {
1080 	return DEFAULT_SYNC_REFRESH_PERIOD;
1081 }
1082 
1083 static inline int sysctl_sync_retries(struct netns_ipvs *ipvs)
1084 {
1085 	return DEFAULT_SYNC_RETRIES & 3;
1086 }
1087 
1088 static inline int sysctl_sync_ver(struct netns_ipvs *ipvs)
1089 {
1090 	return DEFAULT_SYNC_VER;
1091 }
1092 
1093 static inline int sysctl_sloppy_tcp(struct netns_ipvs *ipvs)
1094 {
1095 	return DEFAULT_SLOPPY_TCP;
1096 }
1097 
1098 static inline int sysctl_sloppy_sctp(struct netns_ipvs *ipvs)
1099 {
1100 	return DEFAULT_SLOPPY_SCTP;
1101 }
1102 
1103 static inline int sysctl_sync_ports(struct netns_ipvs *ipvs)
1104 {
1105 	return 1;
1106 }
1107 
1108 static inline int sysctl_sync_persist_mode(struct netns_ipvs *ipvs)
1109 {
1110 	return 0;
1111 }
1112 
1113 static inline unsigned long sysctl_sync_qlen_max(struct netns_ipvs *ipvs)
1114 {
1115 	return IPVS_SYNC_QLEN_MAX;
1116 }
1117 
1118 static inline int sysctl_sync_sock_size(struct netns_ipvs *ipvs)
1119 {
1120 	return 0;
1121 }
1122 
1123 static inline int sysctl_pmtu_disc(struct netns_ipvs *ipvs)
1124 {
1125 	return 1;
1126 }
1127 
1128 static inline int sysctl_backup_only(struct netns_ipvs *ipvs)
1129 {
1130 	return 0;
1131 }
1132 
1133 static inline int sysctl_conn_reuse_mode(struct netns_ipvs *ipvs)
1134 {
1135 	return 1;
1136 }
1137 
1138 static inline int sysctl_schedule_icmp(struct netns_ipvs *ipvs)
1139 {
1140 	return 0;
1141 }
1142 
1143 static inline int sysctl_ignore_tunneled(struct netns_ipvs *ipvs)
1144 {
1145 	return 0;
1146 }
1147 
1148 static inline int sysctl_cache_bypass(struct netns_ipvs *ipvs)
1149 {
1150 	return 0;
1151 }
1152 
1153 #endif
1154 
1155 /* IPVS core functions
1156  * (from ip_vs_core.c)
1157  */
1158 const char *ip_vs_proto_name(unsigned int proto);
1159 void ip_vs_init_hash_table(struct list_head *table, int rows);
1160 struct ip_vs_conn *ip_vs_new_conn_out(struct ip_vs_service *svc,
1161 				      struct ip_vs_dest *dest,
1162 				      struct sk_buff *skb,
1163 				      const struct ip_vs_iphdr *iph,
1164 				      __be16 dport,
1165 				      __be16 cport);
1166 #define IP_VS_INIT_HASH_TABLE(t) ip_vs_init_hash_table((t), ARRAY_SIZE((t)))
1167 
1168 #define IP_VS_APP_TYPE_FTP	1
1169 
1170 /* ip_vs_conn handling functions
1171  * (from ip_vs_conn.c)
1172  */
1173 enum {
1174 	IP_VS_DIR_INPUT = 0,
1175 	IP_VS_DIR_OUTPUT,
1176 	IP_VS_DIR_INPUT_ONLY,
1177 	IP_VS_DIR_LAST,
1178 };
1179 
1180 static inline void ip_vs_conn_fill_param(struct netns_ipvs *ipvs, int af, int protocol,
1181 					 const union nf_inet_addr *caddr,
1182 					 __be16 cport,
1183 					 const union nf_inet_addr *vaddr,
1184 					 __be16 vport,
1185 					 struct ip_vs_conn_param *p)
1186 {
1187 	p->ipvs = ipvs;
1188 	p->af = af;
1189 	p->protocol = protocol;
1190 	p->caddr = caddr;
1191 	p->cport = cport;
1192 	p->vaddr = vaddr;
1193 	p->vport = vport;
1194 	p->pe = NULL;
1195 	p->pe_data = NULL;
1196 }
1197 
1198 struct ip_vs_conn *ip_vs_conn_in_get(const struct ip_vs_conn_param *p);
1199 struct ip_vs_conn *ip_vs_ct_in_get(const struct ip_vs_conn_param *p);
1200 
1201 struct ip_vs_conn * ip_vs_conn_in_get_proto(struct netns_ipvs *ipvs, int af,
1202 					    const struct sk_buff *skb,
1203 					    const struct ip_vs_iphdr *iph);
1204 
1205 struct ip_vs_conn *ip_vs_conn_out_get(const struct ip_vs_conn_param *p);
1206 
1207 struct ip_vs_conn * ip_vs_conn_out_get_proto(struct netns_ipvs *ipvs, int af,
1208 					     const struct sk_buff *skb,
1209 					     const struct ip_vs_iphdr *iph);
1210 
1211 /* Get reference to gain full access to conn.
1212  * By default, RCU read-side critical sections have access only to
1213  * conn fields and its PE data, see ip_vs_conn_rcu_free() for reference.
1214  */
1215 static inline bool __ip_vs_conn_get(struct ip_vs_conn *cp)
1216 {
1217 	return refcount_inc_not_zero(&cp->refcnt);
1218 }
1219 
1220 /* put back the conn without restarting its timer */
1221 static inline void __ip_vs_conn_put(struct ip_vs_conn *cp)
1222 {
1223 	smp_mb__before_atomic();
1224 	refcount_dec(&cp->refcnt);
1225 }
1226 void ip_vs_conn_put(struct ip_vs_conn *cp);
1227 void ip_vs_conn_fill_cport(struct ip_vs_conn *cp, __be16 cport);
1228 
1229 struct ip_vs_conn *ip_vs_conn_new(const struct ip_vs_conn_param *p, int dest_af,
1230 				  const union nf_inet_addr *daddr,
1231 				  __be16 dport, unsigned int flags,
1232 				  struct ip_vs_dest *dest, __u32 fwmark);
1233 void ip_vs_conn_expire_now(struct ip_vs_conn *cp);
1234 
1235 const char *ip_vs_state_name(__u16 proto, int state);
1236 
1237 void ip_vs_tcp_conn_listen(struct ip_vs_conn *cp);
1238 int ip_vs_check_template(struct ip_vs_conn *ct, struct ip_vs_dest *cdest);
1239 void ip_vs_random_dropentry(struct netns_ipvs *ipvs);
1240 int ip_vs_conn_init(void);
1241 void ip_vs_conn_cleanup(void);
1242 
1243 static inline void ip_vs_control_del(struct ip_vs_conn *cp)
1244 {
1245 	struct ip_vs_conn *ctl_cp = cp->control;
1246 	if (!ctl_cp) {
1247 		IP_VS_ERR_BUF("request control DEL for uncontrolled: "
1248 			      "%s:%d to %s:%d\n",
1249 			      IP_VS_DBG_ADDR(cp->af, &cp->caddr),
1250 			      ntohs(cp->cport),
1251 			      IP_VS_DBG_ADDR(cp->af, &cp->vaddr),
1252 			      ntohs(cp->vport));
1253 
1254 		return;
1255 	}
1256 
1257 	IP_VS_DBG_BUF(7, "DELeting control for: "
1258 		      "cp.dst=%s:%d ctl_cp.dst=%s:%d\n",
1259 		      IP_VS_DBG_ADDR(cp->af, &cp->caddr),
1260 		      ntohs(cp->cport),
1261 		      IP_VS_DBG_ADDR(cp->af, &ctl_cp->caddr),
1262 		      ntohs(ctl_cp->cport));
1263 
1264 	cp->control = NULL;
1265 	if (atomic_read(&ctl_cp->n_control) == 0) {
1266 		IP_VS_ERR_BUF("BUG control DEL with n=0 : "
1267 			      "%s:%d to %s:%d\n",
1268 			      IP_VS_DBG_ADDR(cp->af, &cp->caddr),
1269 			      ntohs(cp->cport),
1270 			      IP_VS_DBG_ADDR(cp->af, &cp->vaddr),
1271 			      ntohs(cp->vport));
1272 
1273 		return;
1274 	}
1275 	atomic_dec(&ctl_cp->n_control);
1276 }
1277 
1278 static inline void
1279 ip_vs_control_add(struct ip_vs_conn *cp, struct ip_vs_conn *ctl_cp)
1280 {
1281 	if (cp->control) {
1282 		IP_VS_ERR_BUF("request control ADD for already controlled: "
1283 			      "%s:%d to %s:%d\n",
1284 			      IP_VS_DBG_ADDR(cp->af, &cp->caddr),
1285 			      ntohs(cp->cport),
1286 			      IP_VS_DBG_ADDR(cp->af, &cp->vaddr),
1287 			      ntohs(cp->vport));
1288 
1289 		ip_vs_control_del(cp);
1290 	}
1291 
1292 	IP_VS_DBG_BUF(7, "ADDing control for: "
1293 		      "cp.dst=%s:%d ctl_cp.dst=%s:%d\n",
1294 		      IP_VS_DBG_ADDR(cp->af, &cp->caddr),
1295 		      ntohs(cp->cport),
1296 		      IP_VS_DBG_ADDR(cp->af, &ctl_cp->caddr),
1297 		      ntohs(ctl_cp->cport));
1298 
1299 	cp->control = ctl_cp;
1300 	atomic_inc(&ctl_cp->n_control);
1301 }
1302 
1303 /* IPVS netns init & cleanup functions */
1304 int ip_vs_estimator_net_init(struct netns_ipvs *ipvs);
1305 int ip_vs_control_net_init(struct netns_ipvs *ipvs);
1306 int ip_vs_protocol_net_init(struct netns_ipvs *ipvs);
1307 int ip_vs_app_net_init(struct netns_ipvs *ipvs);
1308 int ip_vs_conn_net_init(struct netns_ipvs *ipvs);
1309 int ip_vs_sync_net_init(struct netns_ipvs *ipvs);
1310 void ip_vs_conn_net_cleanup(struct netns_ipvs *ipvs);
1311 void ip_vs_app_net_cleanup(struct netns_ipvs *ipvs);
1312 void ip_vs_protocol_net_cleanup(struct netns_ipvs *ipvs);
1313 void ip_vs_control_net_cleanup(struct netns_ipvs *ipvs);
1314 void ip_vs_estimator_net_cleanup(struct netns_ipvs *ipvs);
1315 void ip_vs_sync_net_cleanup(struct netns_ipvs *ipvs);
1316 void ip_vs_service_net_cleanup(struct netns_ipvs *ipvs);
1317 
1318 /* IPVS application functions
1319  * (from ip_vs_app.c)
1320  */
1321 #define IP_VS_APP_MAX_PORTS  8
1322 struct ip_vs_app *register_ip_vs_app(struct netns_ipvs *ipvs, struct ip_vs_app *app);
1323 void unregister_ip_vs_app(struct netns_ipvs *ipvs, struct ip_vs_app *app);
1324 int ip_vs_bind_app(struct ip_vs_conn *cp, struct ip_vs_protocol *pp);
1325 void ip_vs_unbind_app(struct ip_vs_conn *cp);
1326 int register_ip_vs_app_inc(struct netns_ipvs *ipvs, struct ip_vs_app *app, __u16 proto,
1327 			   __u16 port);
1328 int ip_vs_app_inc_get(struct ip_vs_app *inc);
1329 void ip_vs_app_inc_put(struct ip_vs_app *inc);
1330 
1331 int ip_vs_app_pkt_out(struct ip_vs_conn *, struct sk_buff *skb);
1332 int ip_vs_app_pkt_in(struct ip_vs_conn *, struct sk_buff *skb);
1333 
1334 int register_ip_vs_pe(struct ip_vs_pe *pe);
1335 int unregister_ip_vs_pe(struct ip_vs_pe *pe);
1336 struct ip_vs_pe *ip_vs_pe_getbyname(const char *name);
1337 struct ip_vs_pe *__ip_vs_pe_getbyname(const char *pe_name);
1338 
1339 /* Use a #define to avoid all of module.h just for these trivial ops */
1340 #define ip_vs_pe_get(pe)			\
1341 	if (pe && pe->module)			\
1342 		__module_get(pe->module);
1343 
1344 #define ip_vs_pe_put(pe)			\
1345 	if (pe && pe->module)			\
1346 		module_put(pe->module);
1347 
1348 /* IPVS protocol functions (from ip_vs_proto.c) */
1349 int ip_vs_protocol_init(void);
1350 void ip_vs_protocol_cleanup(void);
1351 void ip_vs_protocol_timeout_change(struct netns_ipvs *ipvs, int flags);
1352 int *ip_vs_create_timeout_table(int *table, int size);
1353 void ip_vs_tcpudp_debug_packet(int af, struct ip_vs_protocol *pp,
1354 			       const struct sk_buff *skb, int offset,
1355 			       const char *msg);
1356 
1357 extern struct ip_vs_protocol ip_vs_protocol_tcp;
1358 extern struct ip_vs_protocol ip_vs_protocol_udp;
1359 extern struct ip_vs_protocol ip_vs_protocol_icmp;
1360 extern struct ip_vs_protocol ip_vs_protocol_esp;
1361 extern struct ip_vs_protocol ip_vs_protocol_ah;
1362 extern struct ip_vs_protocol ip_vs_protocol_sctp;
1363 
1364 /* Registering/unregistering scheduler functions
1365  * (from ip_vs_sched.c)
1366  */
1367 int register_ip_vs_scheduler(struct ip_vs_scheduler *scheduler);
1368 int unregister_ip_vs_scheduler(struct ip_vs_scheduler *scheduler);
1369 int ip_vs_bind_scheduler(struct ip_vs_service *svc,
1370 			 struct ip_vs_scheduler *scheduler);
1371 void ip_vs_unbind_scheduler(struct ip_vs_service *svc,
1372 			    struct ip_vs_scheduler *sched);
1373 struct ip_vs_scheduler *ip_vs_scheduler_get(const char *sched_name);
1374 void ip_vs_scheduler_put(struct ip_vs_scheduler *scheduler);
1375 struct ip_vs_conn *
1376 ip_vs_schedule(struct ip_vs_service *svc, struct sk_buff *skb,
1377 	       struct ip_vs_proto_data *pd, int *ignored,
1378 	       struct ip_vs_iphdr *iph);
1379 int ip_vs_leave(struct ip_vs_service *svc, struct sk_buff *skb,
1380 		struct ip_vs_proto_data *pd, struct ip_vs_iphdr *iph);
1381 
1382 void ip_vs_scheduler_err(struct ip_vs_service *svc, const char *msg);
1383 
1384 /* IPVS control data and functions (from ip_vs_ctl.c) */
1385 extern struct ip_vs_stats ip_vs_stats;
1386 extern int sysctl_ip_vs_sync_ver;
1387 
1388 struct ip_vs_service *
1389 ip_vs_service_find(struct netns_ipvs *ipvs, int af, __u32 fwmark, __u16 protocol,
1390 		  const union nf_inet_addr *vaddr, __be16 vport);
1391 
1392 bool ip_vs_has_real_service(struct netns_ipvs *ipvs, int af, __u16 protocol,
1393 			    const union nf_inet_addr *daddr, __be16 dport);
1394 
1395 struct ip_vs_dest *
1396 ip_vs_find_real_service(struct netns_ipvs *ipvs, int af, __u16 protocol,
1397 			const union nf_inet_addr *daddr, __be16 dport);
1398 
1399 int ip_vs_use_count_inc(void);
1400 void ip_vs_use_count_dec(void);
1401 int ip_vs_register_nl_ioctl(void);
1402 void ip_vs_unregister_nl_ioctl(void);
1403 int ip_vs_control_init(void);
1404 void ip_vs_control_cleanup(void);
1405 struct ip_vs_dest *
1406 ip_vs_find_dest(struct netns_ipvs *ipvs, int svc_af, int dest_af,
1407 		const union nf_inet_addr *daddr, __be16 dport,
1408 		const union nf_inet_addr *vaddr, __be16 vport,
1409 		__u16 protocol, __u32 fwmark, __u32 flags);
1410 void ip_vs_try_bind_dest(struct ip_vs_conn *cp);
1411 
1412 static inline void ip_vs_dest_hold(struct ip_vs_dest *dest)
1413 {
1414 	refcount_inc(&dest->refcnt);
1415 }
1416 
1417 static inline void ip_vs_dest_put(struct ip_vs_dest *dest)
1418 {
1419 	smp_mb__before_atomic();
1420 	refcount_dec(&dest->refcnt);
1421 }
1422 
1423 static inline void ip_vs_dest_put_and_free(struct ip_vs_dest *dest)
1424 {
1425 	if (refcount_dec_and_test(&dest->refcnt))
1426 		kfree(dest);
1427 }
1428 
1429 /* IPVS sync daemon data and function prototypes
1430  * (from ip_vs_sync.c)
1431  */
1432 int start_sync_thread(struct netns_ipvs *ipvs, struct ipvs_sync_daemon_cfg *cfg,
1433 		      int state);
1434 int stop_sync_thread(struct netns_ipvs *ipvs, int state);
1435 void ip_vs_sync_conn(struct netns_ipvs *ipvs, struct ip_vs_conn *cp, int pkts);
1436 
1437 /* IPVS rate estimator prototypes (from ip_vs_est.c) */
1438 void ip_vs_start_estimator(struct netns_ipvs *ipvs, struct ip_vs_stats *stats);
1439 void ip_vs_stop_estimator(struct netns_ipvs *ipvs, struct ip_vs_stats *stats);
1440 void ip_vs_zero_estimator(struct ip_vs_stats *stats);
1441 void ip_vs_read_estimator(struct ip_vs_kstats *dst, struct ip_vs_stats *stats);
1442 
1443 /* Various IPVS packet transmitters (from ip_vs_xmit.c) */
1444 int ip_vs_null_xmit(struct sk_buff *skb, struct ip_vs_conn *cp,
1445 		    struct ip_vs_protocol *pp, struct ip_vs_iphdr *iph);
1446 int ip_vs_bypass_xmit(struct sk_buff *skb, struct ip_vs_conn *cp,
1447 		      struct ip_vs_protocol *pp, struct ip_vs_iphdr *iph);
1448 int ip_vs_nat_xmit(struct sk_buff *skb, struct ip_vs_conn *cp,
1449 		   struct ip_vs_protocol *pp, struct ip_vs_iphdr *iph);
1450 int ip_vs_tunnel_xmit(struct sk_buff *skb, struct ip_vs_conn *cp,
1451 		      struct ip_vs_protocol *pp, struct ip_vs_iphdr *iph);
1452 int ip_vs_dr_xmit(struct sk_buff *skb, struct ip_vs_conn *cp,
1453 		  struct ip_vs_protocol *pp, struct ip_vs_iphdr *iph);
1454 int ip_vs_icmp_xmit(struct sk_buff *skb, struct ip_vs_conn *cp,
1455 		    struct ip_vs_protocol *pp, int offset,
1456 		    unsigned int hooknum, struct ip_vs_iphdr *iph);
1457 void ip_vs_dest_dst_rcu_free(struct rcu_head *head);
1458 
1459 #ifdef CONFIG_IP_VS_IPV6
1460 int ip_vs_bypass_xmit_v6(struct sk_buff *skb, struct ip_vs_conn *cp,
1461 			 struct ip_vs_protocol *pp, struct ip_vs_iphdr *iph);
1462 int ip_vs_nat_xmit_v6(struct sk_buff *skb, struct ip_vs_conn *cp,
1463 		      struct ip_vs_protocol *pp, struct ip_vs_iphdr *iph);
1464 int ip_vs_tunnel_xmit_v6(struct sk_buff *skb, struct ip_vs_conn *cp,
1465 			 struct ip_vs_protocol *pp, struct ip_vs_iphdr *iph);
1466 int ip_vs_dr_xmit_v6(struct sk_buff *skb, struct ip_vs_conn *cp,
1467 		     struct ip_vs_protocol *pp, struct ip_vs_iphdr *iph);
1468 int ip_vs_icmp_xmit_v6(struct sk_buff *skb, struct ip_vs_conn *cp,
1469 		       struct ip_vs_protocol *pp, int offset,
1470 		       unsigned int hooknum, struct ip_vs_iphdr *iph);
1471 #endif
1472 
1473 #ifdef CONFIG_SYSCTL
1474 /* This is a simple mechanism to ignore packets when
1475  * we are loaded. Just set ip_vs_drop_rate to 'n' and
1476  * we start to drop 1/rate of the packets
1477  */
1478 static inline int ip_vs_todrop(struct netns_ipvs *ipvs)
1479 {
1480 	if (!ipvs->drop_rate)
1481 		return 0;
1482 	if (--ipvs->drop_counter > 0)
1483 		return 0;
1484 	ipvs->drop_counter = ipvs->drop_rate;
1485 	return 1;
1486 }
1487 #else
1488 static inline int ip_vs_todrop(struct netns_ipvs *ipvs) { return 0; }
1489 #endif
1490 
1491 /* ip_vs_fwd_tag returns the forwarding tag of the connection */
1492 #define IP_VS_FWD_METHOD(cp)  (cp->flags & IP_VS_CONN_F_FWD_MASK)
1493 
1494 static inline char ip_vs_fwd_tag(struct ip_vs_conn *cp)
1495 {
1496 	char fwd;
1497 
1498 	switch (IP_VS_FWD_METHOD(cp)) {
1499 	case IP_VS_CONN_F_MASQ:
1500 		fwd = 'M'; break;
1501 	case IP_VS_CONN_F_LOCALNODE:
1502 		fwd = 'L'; break;
1503 	case IP_VS_CONN_F_TUNNEL:
1504 		fwd = 'T'; break;
1505 	case IP_VS_CONN_F_DROUTE:
1506 		fwd = 'R'; break;
1507 	case IP_VS_CONN_F_BYPASS:
1508 		fwd = 'B'; break;
1509 	default:
1510 		fwd = '?'; break;
1511 	}
1512 	return fwd;
1513 }
1514 
1515 void ip_vs_nat_icmp(struct sk_buff *skb, struct ip_vs_protocol *pp,
1516 		    struct ip_vs_conn *cp, int dir);
1517 
1518 #ifdef CONFIG_IP_VS_IPV6
1519 void ip_vs_nat_icmp_v6(struct sk_buff *skb, struct ip_vs_protocol *pp,
1520 		       struct ip_vs_conn *cp, int dir);
1521 #endif
1522 
1523 __sum16 ip_vs_checksum_complete(struct sk_buff *skb, int offset);
1524 
1525 static inline __wsum ip_vs_check_diff4(__be32 old, __be32 new, __wsum oldsum)
1526 {
1527 	__be32 diff[2] = { ~old, new };
1528 
1529 	return csum_partial(diff, sizeof(diff), oldsum);
1530 }
1531 
1532 #ifdef CONFIG_IP_VS_IPV6
1533 static inline __wsum ip_vs_check_diff16(const __be32 *old, const __be32 *new,
1534 					__wsum oldsum)
1535 {
1536 	__be32 diff[8] = { ~old[3], ~old[2], ~old[1], ~old[0],
1537 			    new[3],  new[2],  new[1],  new[0] };
1538 
1539 	return csum_partial(diff, sizeof(diff), oldsum);
1540 }
1541 #endif
1542 
1543 static inline __wsum ip_vs_check_diff2(__be16 old, __be16 new, __wsum oldsum)
1544 {
1545 	__be16 diff[2] = { ~old, new };
1546 
1547 	return csum_partial(diff, sizeof(diff), oldsum);
1548 }
1549 
1550 /* Forget current conntrack (unconfirmed) and attach notrack entry */
1551 static inline void ip_vs_notrack(struct sk_buff *skb)
1552 {
1553 #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
1554 	enum ip_conntrack_info ctinfo;
1555 	struct nf_conn *ct = nf_ct_get(skb, &ctinfo);
1556 
1557 	if (ct) {
1558 		nf_conntrack_put(&ct->ct_general);
1559 		nf_ct_set(skb, NULL, IP_CT_UNTRACKED);
1560 	}
1561 #endif
1562 }
1563 
1564 #ifdef CONFIG_IP_VS_NFCT
1565 /* Netfilter connection tracking
1566  * (from ip_vs_nfct.c)
1567  */
1568 static inline int ip_vs_conntrack_enabled(struct netns_ipvs *ipvs)
1569 {
1570 #ifdef CONFIG_SYSCTL
1571 	return ipvs->sysctl_conntrack;
1572 #else
1573 	return 0;
1574 #endif
1575 }
1576 
1577 void ip_vs_update_conntrack(struct sk_buff *skb, struct ip_vs_conn *cp,
1578 			    int outin);
1579 int ip_vs_confirm_conntrack(struct sk_buff *skb);
1580 void ip_vs_nfct_expect_related(struct sk_buff *skb, struct nf_conn *ct,
1581 			       struct ip_vs_conn *cp, u_int8_t proto,
1582 			       const __be16 port, int from_rs);
1583 void ip_vs_conn_drop_conntrack(struct ip_vs_conn *cp);
1584 
1585 #else
1586 
1587 static inline int ip_vs_conntrack_enabled(struct netns_ipvs *ipvs)
1588 {
1589 	return 0;
1590 }
1591 
1592 static inline void ip_vs_update_conntrack(struct sk_buff *skb,
1593 					  struct ip_vs_conn *cp, int outin)
1594 {
1595 }
1596 
1597 static inline int ip_vs_confirm_conntrack(struct sk_buff *skb)
1598 {
1599 	return NF_ACCEPT;
1600 }
1601 
1602 static inline void ip_vs_conn_drop_conntrack(struct ip_vs_conn *cp)
1603 {
1604 }
1605 #endif /* CONFIG_IP_VS_NFCT */
1606 
1607 /* Really using conntrack? */
1608 static inline bool ip_vs_conn_uses_conntrack(struct ip_vs_conn *cp,
1609 					     struct sk_buff *skb)
1610 {
1611 #ifdef CONFIG_IP_VS_NFCT
1612 	enum ip_conntrack_info ctinfo;
1613 	struct nf_conn *ct;
1614 
1615 	if (!(cp->flags & IP_VS_CONN_F_NFCT))
1616 		return false;
1617 	ct = nf_ct_get(skb, &ctinfo);
1618 	if (ct)
1619 		return true;
1620 #endif
1621 	return false;
1622 }
1623 
1624 static inline int
1625 ip_vs_dest_conn_overhead(struct ip_vs_dest *dest)
1626 {
1627 	/* We think the overhead of processing active connections is 256
1628 	 * times higher than that of inactive connections in average. (This
1629 	 * 256 times might not be accurate, we will change it later) We
1630 	 * use the following formula to estimate the overhead now:
1631 	 *		  dest->activeconns*256 + dest->inactconns
1632 	 */
1633 	return (atomic_read(&dest->activeconns) << 8) +
1634 		atomic_read(&dest->inactconns);
1635 }
1636 
1637 #endif	/* _NET_IP_VS_H */
1638