xref: /openbmc/linux/include/net/ip_vs.h (revision 5b628549)
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 /* Connections' size value needed by ip_vs_ctl.c */
45 extern int ip_vs_conn_tab_size;
46 
47 struct ip_vs_iphdr {
48 	int hdr_flags;	/* ipvs flags */
49 	__u32 off;	/* Where IP or IPv4 header starts */
50 	__u32 len;	/* IPv4 simply where L4 starts
51 			 * IPv6 where L4 Transport Header starts */
52 	__u16 fragoffs; /* IPv6 fragment offset, 0 if first frag (or not frag)*/
53 	__s16 protocol;
54 	__s32 flags;
55 	union nf_inet_addr saddr;
56 	union nf_inet_addr daddr;
57 };
58 
59 static inline void *frag_safe_skb_hp(const struct sk_buff *skb, int offset,
60 				      int len, void *buffer)
61 {
62 	return skb_header_pointer(skb, offset, len, buffer);
63 }
64 
65 /* This function handles filling *ip_vs_iphdr, both for IPv4 and IPv6.
66  * IPv6 requires some extra work, as finding proper header position,
67  * depend on the IPv6 extension headers.
68  */
69 static inline int
70 ip_vs_fill_iph_skb_off(int af, const struct sk_buff *skb, int offset,
71 		       int hdr_flags, struct ip_vs_iphdr *iphdr)
72 {
73 	iphdr->hdr_flags = hdr_flags;
74 	iphdr->off = offset;
75 
76 #ifdef CONFIG_IP_VS_IPV6
77 	if (af == AF_INET6) {
78 		struct ipv6hdr _iph;
79 		const struct ipv6hdr *iph = skb_header_pointer(
80 			skb, offset, sizeof(_iph), &_iph);
81 		if (!iph)
82 			return 0;
83 
84 		iphdr->saddr.in6 = iph->saddr;
85 		iphdr->daddr.in6 = iph->daddr;
86 		/* ipv6_find_hdr() updates len, flags */
87 		iphdr->len	 = offset;
88 		iphdr->flags	 = 0;
89 		iphdr->protocol  = ipv6_find_hdr(skb, &iphdr->len, -1,
90 						 &iphdr->fragoffs,
91 						 &iphdr->flags);
92 		if (iphdr->protocol < 0)
93 			return 0;
94 	} else
95 #endif
96 	{
97 		struct iphdr _iph;
98 		const struct iphdr *iph = skb_header_pointer(
99 			skb, offset, sizeof(_iph), &_iph);
100 		if (!iph)
101 			return 0;
102 
103 		iphdr->len	= offset + iph->ihl * 4;
104 		iphdr->fragoffs	= 0;
105 		iphdr->protocol	= iph->protocol;
106 		iphdr->saddr.ip	= iph->saddr;
107 		iphdr->daddr.ip	= iph->daddr;
108 	}
109 
110 	return 1;
111 }
112 
113 static inline int
114 ip_vs_fill_iph_skb_icmp(int af, const struct sk_buff *skb, int offset,
115 			bool inverse, struct ip_vs_iphdr *iphdr)
116 {
117 	int hdr_flags = IP_VS_HDR_ICMP;
118 
119 	if (inverse)
120 		hdr_flags |= IP_VS_HDR_INVERSE;
121 
122 	return ip_vs_fill_iph_skb_off(af, skb, offset, hdr_flags, iphdr);
123 }
124 
125 static inline int
126 ip_vs_fill_iph_skb(int af, const struct sk_buff *skb, bool inverse,
127 		   struct ip_vs_iphdr *iphdr)
128 {
129 	int hdr_flags = 0;
130 
131 	if (inverse)
132 		hdr_flags |= IP_VS_HDR_INVERSE;
133 
134 	return ip_vs_fill_iph_skb_off(af, skb, skb_network_offset(skb),
135 				      hdr_flags, iphdr);
136 }
137 
138 static inline bool
139 ip_vs_iph_inverse(const struct ip_vs_iphdr *iph)
140 {
141 	return !!(iph->hdr_flags & IP_VS_HDR_INVERSE);
142 }
143 
144 static inline bool
145 ip_vs_iph_icmp(const struct ip_vs_iphdr *iph)
146 {
147 	return !!(iph->hdr_flags & IP_VS_HDR_ICMP);
148 }
149 
150 static inline void ip_vs_addr_copy(int af, union nf_inet_addr *dst,
151 				   const union nf_inet_addr *src)
152 {
153 #ifdef CONFIG_IP_VS_IPV6
154 	if (af == AF_INET6)
155 		dst->in6 = src->in6;
156 	else
157 #endif
158 	dst->ip = src->ip;
159 }
160 
161 static inline void ip_vs_addr_set(int af, union nf_inet_addr *dst,
162 				  const union nf_inet_addr *src)
163 {
164 #ifdef CONFIG_IP_VS_IPV6
165 	if (af == AF_INET6) {
166 		dst->in6 = src->in6;
167 		return;
168 	}
169 #endif
170 	dst->ip = src->ip;
171 	dst->all[1] = 0;
172 	dst->all[2] = 0;
173 	dst->all[3] = 0;
174 }
175 
176 static inline int ip_vs_addr_equal(int af, const union nf_inet_addr *a,
177 				   const union nf_inet_addr *b)
178 {
179 #ifdef CONFIG_IP_VS_IPV6
180 	if (af == AF_INET6)
181 		return ipv6_addr_equal(&a->in6, &b->in6);
182 #endif
183 	return a->ip == b->ip;
184 }
185 
186 #ifdef CONFIG_IP_VS_DEBUG
187 #include <linux/net.h>
188 
189 int ip_vs_get_debug_level(void);
190 
191 static inline const char *ip_vs_dbg_addr(int af, char *buf, size_t buf_len,
192 					 const union nf_inet_addr *addr,
193 					 int *idx)
194 {
195 	int len;
196 #ifdef CONFIG_IP_VS_IPV6
197 	if (af == AF_INET6)
198 		len = snprintf(&buf[*idx], buf_len - *idx, "[%pI6c]",
199 			       &addr->in6) + 1;
200 	else
201 #endif
202 		len = snprintf(&buf[*idx], buf_len - *idx, "%pI4",
203 			       &addr->ip) + 1;
204 
205 	*idx += len;
206 	BUG_ON(*idx > buf_len + 1);
207 	return &buf[*idx - len];
208 }
209 
210 #define IP_VS_DBG_BUF(level, msg, ...)					\
211 	do {								\
212 		char ip_vs_dbg_buf[160];				\
213 		int ip_vs_dbg_idx = 0;					\
214 		if (level <= ip_vs_get_debug_level())			\
215 			printk(KERN_DEBUG pr_fmt(msg), ##__VA_ARGS__);	\
216 	} while (0)
217 #define IP_VS_ERR_BUF(msg...)						\
218 	do {								\
219 		char ip_vs_dbg_buf[160];				\
220 		int ip_vs_dbg_idx = 0;					\
221 		pr_err(msg);						\
222 	} while (0)
223 
224 /* Only use from within IP_VS_DBG_BUF() or IP_VS_ERR_BUF macros */
225 #define IP_VS_DBG_ADDR(af, addr)					\
226 	ip_vs_dbg_addr(af, ip_vs_dbg_buf,				\
227 		       sizeof(ip_vs_dbg_buf), addr,			\
228 		       &ip_vs_dbg_idx)
229 
230 #define IP_VS_DBG(level, msg, ...)					\
231 	do {								\
232 		if (level <= ip_vs_get_debug_level())			\
233 			printk(KERN_DEBUG pr_fmt(msg), ##__VA_ARGS__);	\
234 	} while (0)
235 #define IP_VS_DBG_RL(msg, ...)						\
236 	do {								\
237 		if (net_ratelimit())					\
238 			printk(KERN_DEBUG pr_fmt(msg), ##__VA_ARGS__);	\
239 	} while (0)
240 #define IP_VS_DBG_PKT(level, af, pp, skb, ofs, msg)			\
241 	do {								\
242 		if (level <= ip_vs_get_debug_level())			\
243 			pp->debug_packet(af, pp, skb, ofs, msg);	\
244 	} while (0)
245 #define IP_VS_DBG_RL_PKT(level, af, pp, skb, ofs, msg)			\
246 	do {								\
247 		if (level <= ip_vs_get_debug_level() &&			\
248 		    net_ratelimit())					\
249 			pp->debug_packet(af, pp, skb, ofs, msg);	\
250 	} while (0)
251 #else	/* NO DEBUGGING at ALL */
252 #define IP_VS_DBG_BUF(level, msg...)  do {} while (0)
253 #define IP_VS_ERR_BUF(msg...)  do {} while (0)
254 #define IP_VS_DBG(level, msg...)  do {} while (0)
255 #define IP_VS_DBG_RL(msg...)  do {} while (0)
256 #define IP_VS_DBG_PKT(level, af, pp, skb, ofs, msg)	do {} while (0)
257 #define IP_VS_DBG_RL_PKT(level, af, pp, skb, ofs, msg)	do {} while (0)
258 #endif
259 
260 #define IP_VS_BUG() BUG()
261 #define IP_VS_ERR_RL(msg, ...)						\
262 	do {								\
263 		if (net_ratelimit())					\
264 			pr_err(msg, ##__VA_ARGS__);			\
265 	} while (0)
266 
267 #ifdef CONFIG_IP_VS_DEBUG
268 #define EnterFunction(level)						\
269 	do {								\
270 		if (level <= ip_vs_get_debug_level())			\
271 			printk(KERN_DEBUG				\
272 			       pr_fmt("Enter: %s, %s line %i\n"),	\
273 			       __func__, __FILE__, __LINE__);		\
274 	} while (0)
275 #define LeaveFunction(level)						\
276 	do {								\
277 		if (level <= ip_vs_get_debug_level())			\
278 			printk(KERN_DEBUG				\
279 			       pr_fmt("Leave: %s, %s line %i\n"),	\
280 			       __func__, __FILE__, __LINE__);		\
281 	} while (0)
282 #else
283 #define EnterFunction(level)   do {} while (0)
284 #define LeaveFunction(level)   do {} while (0)
285 #endif
286 
287 /* The port number of FTP service (in network order). */
288 #define FTPPORT  cpu_to_be16(21)
289 #define FTPDATA  cpu_to_be16(20)
290 
291 /* TCP State Values */
292 enum {
293 	IP_VS_TCP_S_NONE = 0,
294 	IP_VS_TCP_S_ESTABLISHED,
295 	IP_VS_TCP_S_SYN_SENT,
296 	IP_VS_TCP_S_SYN_RECV,
297 	IP_VS_TCP_S_FIN_WAIT,
298 	IP_VS_TCP_S_TIME_WAIT,
299 	IP_VS_TCP_S_CLOSE,
300 	IP_VS_TCP_S_CLOSE_WAIT,
301 	IP_VS_TCP_S_LAST_ACK,
302 	IP_VS_TCP_S_LISTEN,
303 	IP_VS_TCP_S_SYNACK,
304 	IP_VS_TCP_S_LAST
305 };
306 
307 /* UDP State Values */
308 enum {
309 	IP_VS_UDP_S_NORMAL,
310 	IP_VS_UDP_S_LAST,
311 };
312 
313 /* ICMP State Values */
314 enum {
315 	IP_VS_ICMP_S_NORMAL,
316 	IP_VS_ICMP_S_LAST,
317 };
318 
319 /* SCTP State Values */
320 enum ip_vs_sctp_states {
321 	IP_VS_SCTP_S_NONE,
322 	IP_VS_SCTP_S_INIT1,
323 	IP_VS_SCTP_S_INIT,
324 	IP_VS_SCTP_S_COOKIE_SENT,
325 	IP_VS_SCTP_S_COOKIE_REPLIED,
326 	IP_VS_SCTP_S_COOKIE_WAIT,
327 	IP_VS_SCTP_S_COOKIE,
328 	IP_VS_SCTP_S_COOKIE_ECHOED,
329 	IP_VS_SCTP_S_ESTABLISHED,
330 	IP_VS_SCTP_S_SHUTDOWN_SENT,
331 	IP_VS_SCTP_S_SHUTDOWN_RECEIVED,
332 	IP_VS_SCTP_S_SHUTDOWN_ACK_SENT,
333 	IP_VS_SCTP_S_REJECTED,
334 	IP_VS_SCTP_S_CLOSED,
335 	IP_VS_SCTP_S_LAST
336 };
337 
338 /* Connection templates use bits from state */
339 #define IP_VS_CTPL_S_NONE		0x0000
340 #define IP_VS_CTPL_S_ASSURED		0x0001
341 #define IP_VS_CTPL_S_LAST		0x0002
342 
343 /* Delta sequence info structure
344  * Each ip_vs_conn has 2 (output AND input seq. changes).
345  * Only used in the VS/NAT.
346  */
347 struct ip_vs_seq {
348 	__u32			init_seq;	/* Add delta from this seq */
349 	__u32			delta;		/* Delta in sequence numbers */
350 	__u32			previous_delta;	/* Delta in sequence numbers
351 						 * before last resized pkt */
352 };
353 
354 /* counters per cpu */
355 struct ip_vs_counters {
356 	__u64		conns;		/* connections scheduled */
357 	__u64		inpkts;		/* incoming packets */
358 	__u64		outpkts;	/* outgoing packets */
359 	__u64		inbytes;	/* incoming bytes */
360 	__u64		outbytes;	/* outgoing bytes */
361 };
362 /* Stats per cpu */
363 struct ip_vs_cpu_stats {
364 	struct ip_vs_counters   cnt;
365 	struct u64_stats_sync   syncp;
366 };
367 
368 /* IPVS statistics objects */
369 struct ip_vs_estimator {
370 	struct list_head	list;
371 
372 	u64			last_inbytes;
373 	u64			last_outbytes;
374 	u64			last_conns;
375 	u64			last_inpkts;
376 	u64			last_outpkts;
377 
378 	u64			cps;
379 	u64			inpps;
380 	u64			outpps;
381 	u64			inbps;
382 	u64			outbps;
383 };
384 
385 /*
386  * IPVS statistics object, 64-bit kernel version of struct ip_vs_stats_user
387  */
388 struct ip_vs_kstats {
389 	u64			conns;		/* connections scheduled */
390 	u64			inpkts;		/* incoming packets */
391 	u64			outpkts;	/* outgoing packets */
392 	u64			inbytes;	/* incoming bytes */
393 	u64			outbytes;	/* outgoing bytes */
394 
395 	u64			cps;		/* current connection rate */
396 	u64			inpps;		/* current in packet rate */
397 	u64			outpps;		/* current out packet rate */
398 	u64			inbps;		/* current in byte rate */
399 	u64			outbps;		/* current out byte rate */
400 };
401 
402 struct ip_vs_stats {
403 	struct ip_vs_kstats	kstats;		/* kernel statistics */
404 	struct ip_vs_estimator	est;		/* estimator */
405 	struct ip_vs_cpu_stats __percpu	*cpustats;	/* per cpu counters */
406 	spinlock_t		lock;		/* spin lock */
407 	struct ip_vs_kstats	kstats0;	/* reset values */
408 };
409 
410 struct dst_entry;
411 struct iphdr;
412 struct ip_vs_conn;
413 struct ip_vs_app;
414 struct sk_buff;
415 struct ip_vs_proto_data;
416 
417 struct ip_vs_protocol {
418 	struct ip_vs_protocol	*next;
419 	char			*name;
420 	u16			protocol;
421 	u16			num_states;
422 	int			dont_defrag;
423 
424 	void (*init)(struct ip_vs_protocol *pp);
425 
426 	void (*exit)(struct ip_vs_protocol *pp);
427 
428 	int (*init_netns)(struct netns_ipvs *ipvs, struct ip_vs_proto_data *pd);
429 
430 	void (*exit_netns)(struct netns_ipvs *ipvs, struct ip_vs_proto_data *pd);
431 
432 	int (*conn_schedule)(struct netns_ipvs *ipvs,
433 			     int af, struct sk_buff *skb,
434 			     struct ip_vs_proto_data *pd,
435 			     int *verdict, struct ip_vs_conn **cpp,
436 			     struct ip_vs_iphdr *iph);
437 
438 	struct ip_vs_conn *
439 	(*conn_in_get)(struct netns_ipvs *ipvs,
440 		       int af,
441 		       const struct sk_buff *skb,
442 		       const struct ip_vs_iphdr *iph);
443 
444 	struct ip_vs_conn *
445 	(*conn_out_get)(struct netns_ipvs *ipvs,
446 			int af,
447 			const struct sk_buff *skb,
448 			const struct ip_vs_iphdr *iph);
449 
450 	int (*snat_handler)(struct sk_buff *skb, struct ip_vs_protocol *pp,
451 			    struct ip_vs_conn *cp, struct ip_vs_iphdr *iph);
452 
453 	int (*dnat_handler)(struct sk_buff *skb, struct ip_vs_protocol *pp,
454 			    struct ip_vs_conn *cp, struct ip_vs_iphdr *iph);
455 
456 	const char *(*state_name)(int state);
457 
458 	void (*state_transition)(struct ip_vs_conn *cp, int direction,
459 				 const struct sk_buff *skb,
460 				 struct ip_vs_proto_data *pd);
461 
462 	int (*register_app)(struct netns_ipvs *ipvs, struct ip_vs_app *inc);
463 
464 	void (*unregister_app)(struct netns_ipvs *ipvs, struct ip_vs_app *inc);
465 
466 	int (*app_conn_bind)(struct ip_vs_conn *cp);
467 
468 	void (*debug_packet)(int af, struct ip_vs_protocol *pp,
469 			     const struct sk_buff *skb,
470 			     int offset,
471 			     const char *msg);
472 
473 	void (*timeout_change)(struct ip_vs_proto_data *pd, int flags);
474 };
475 
476 /* protocol data per netns */
477 struct ip_vs_proto_data {
478 	struct ip_vs_proto_data	*next;
479 	struct ip_vs_protocol	*pp;
480 	int			*timeout_table;	/* protocol timeout table */
481 	atomic_t		appcnt;		/* counter of proto app incs. */
482 	struct tcp_states_t	*tcp_state_table;
483 };
484 
485 struct ip_vs_protocol   *ip_vs_proto_get(unsigned short proto);
486 struct ip_vs_proto_data *ip_vs_proto_data_get(struct netns_ipvs *ipvs,
487 					      unsigned short proto);
488 
489 struct ip_vs_conn_param {
490 	struct netns_ipvs		*ipvs;
491 	const union nf_inet_addr	*caddr;
492 	const union nf_inet_addr	*vaddr;
493 	__be16				cport;
494 	__be16				vport;
495 	__u16				protocol;
496 	u16				af;
497 
498 	const struct ip_vs_pe		*pe;
499 	char				*pe_data;
500 	__u8				pe_data_len;
501 };
502 
503 /* IP_VS structure allocated for each dynamically scheduled connection */
504 struct ip_vs_conn {
505 	struct hlist_node	c_list;         /* hashed list heads */
506 	/* Protocol, addresses and port numbers */
507 	__be16                  cport;
508 	__be16                  dport;
509 	__be16                  vport;
510 	u16			af;		/* address family */
511 	union nf_inet_addr      caddr;          /* client address */
512 	union nf_inet_addr      vaddr;          /* virtual address */
513 	union nf_inet_addr      daddr;          /* destination address */
514 	volatile __u32          flags;          /* status flags */
515 	__u16                   protocol;       /* Which protocol (TCP/UDP) */
516 	__u16			daf;		/* Address family of the dest */
517 	struct netns_ipvs	*ipvs;
518 
519 	/* counter and timer */
520 	refcount_t		refcnt;		/* reference count */
521 	struct timer_list	timer;		/* Expiration timer */
522 	volatile unsigned long	timeout;	/* timeout */
523 
524 	/* Flags and state transition */
525 	spinlock_t              lock;           /* lock for state transition */
526 	volatile __u16          state;          /* state info */
527 	volatile __u16          old_state;      /* old state, to be used for
528 						 * state transition triggerd
529 						 * synchronization
530 						 */
531 	__u32			fwmark;		/* Fire wall mark from skb */
532 	unsigned long		sync_endtime;	/* jiffies + sent_retries */
533 
534 	/* Control members */
535 	struct ip_vs_conn       *control;       /* Master control connection */
536 	atomic_t                n_control;      /* Number of controlled ones */
537 	struct ip_vs_dest       *dest;          /* real server */
538 	atomic_t                in_pkts;        /* incoming packet counter */
539 
540 	/* Packet transmitter for different forwarding methods.  If it
541 	 * mangles the packet, it must return NF_DROP or better NF_STOLEN,
542 	 * otherwise this must be changed to a sk_buff **.
543 	 * NF_ACCEPT can be returned when destination is local.
544 	 */
545 	int (*packet_xmit)(struct sk_buff *skb, struct ip_vs_conn *cp,
546 			   struct ip_vs_protocol *pp, struct ip_vs_iphdr *iph);
547 
548 	/* Note: we can group the following members into a structure,
549 	 * in order to save more space, and the following members are
550 	 * only used in VS/NAT anyway
551 	 */
552 	struct ip_vs_app        *app;           /* bound ip_vs_app object */
553 	void                    *app_data;      /* Application private data */
554 	struct ip_vs_seq        in_seq;         /* incoming seq. struct */
555 	struct ip_vs_seq        out_seq;        /* outgoing seq. struct */
556 
557 	const struct ip_vs_pe	*pe;
558 	char			*pe_data;
559 	__u8			pe_data_len;
560 
561 	struct rcu_head		rcu_head;
562 };
563 
564 /* Extended internal versions of struct ip_vs_service_user and ip_vs_dest_user
565  * for IPv6 support.
566  *
567  * We need these to conveniently pass around service and destination
568  * options, but unfortunately, we also need to keep the old definitions to
569  * maintain userspace backwards compatibility for the setsockopt interface.
570  */
571 struct ip_vs_service_user_kern {
572 	/* virtual service addresses */
573 	u16			af;
574 	u16			protocol;
575 	union nf_inet_addr	addr;		/* virtual ip address */
576 	__be16			port;
577 	u32			fwmark;		/* firwall mark of service */
578 
579 	/* virtual service options */
580 	char			*sched_name;
581 	char			*pe_name;
582 	unsigned int		flags;		/* virtual service flags */
583 	unsigned int		timeout;	/* persistent timeout in sec */
584 	__be32			netmask;	/* persistent netmask or plen */
585 };
586 
587 
588 struct ip_vs_dest_user_kern {
589 	/* destination server address */
590 	union nf_inet_addr	addr;
591 	__be16			port;
592 
593 	/* real server options */
594 	unsigned int		conn_flags;	/* connection flags */
595 	int			weight;		/* destination weight */
596 
597 	/* thresholds for active connections */
598 	u32			u_threshold;	/* upper threshold */
599 	u32			l_threshold;	/* lower threshold */
600 
601 	/* Address family of addr */
602 	u16			af;
603 };
604 
605 
606 /*
607  * The information about the virtual service offered to the net and the
608  * forwarding entries.
609  */
610 struct ip_vs_service {
611 	struct hlist_node	s_list;   /* for normal service table */
612 	struct hlist_node	f_list;   /* for fwmark-based service table */
613 	atomic_t		refcnt;   /* reference counter */
614 
615 	u16			af;       /* address family */
616 	__u16			protocol; /* which protocol (TCP/UDP) */
617 	union nf_inet_addr	addr;	  /* IP address for virtual service */
618 	__be16			port;	  /* port number for the service */
619 	__u32                   fwmark;   /* firewall mark of the service */
620 	unsigned int		flags;	  /* service status flags */
621 	unsigned int		timeout;  /* persistent timeout in ticks */
622 	__be32			netmask;  /* grouping granularity, mask/plen */
623 	struct netns_ipvs	*ipvs;
624 
625 	struct list_head	destinations;  /* real server d-linked list */
626 	__u32			num_dests;     /* number of servers */
627 	struct ip_vs_stats      stats;         /* statistics for the service */
628 
629 	/* for scheduling */
630 	struct ip_vs_scheduler __rcu *scheduler; /* bound scheduler object */
631 	spinlock_t		sched_lock;    /* lock sched_data */
632 	void			*sched_data;   /* scheduler application data */
633 
634 	/* alternate persistence engine */
635 	struct ip_vs_pe __rcu	*pe;
636 	int			conntrack_afmask;
637 
638 	struct rcu_head		rcu_head;
639 };
640 
641 /* Information for cached dst */
642 struct ip_vs_dest_dst {
643 	struct dst_entry	*dst_cache;	/* destination cache entry */
644 	u32			dst_cookie;
645 	union nf_inet_addr	dst_saddr;
646 	struct rcu_head		rcu_head;
647 };
648 
649 /* The real server destination forwarding entry with ip address, port number,
650  * and so on.
651  */
652 struct ip_vs_dest {
653 	struct list_head	n_list;   /* for the dests in the service */
654 	struct hlist_node	d_list;   /* for table with all the dests */
655 
656 	u16			af;		/* address family */
657 	__be16			port;		/* port number of the server */
658 	union nf_inet_addr	addr;		/* IP address of the server */
659 	volatile unsigned int	flags;		/* dest status flags */
660 	atomic_t		conn_flags;	/* flags to copy to conn */
661 	atomic_t		weight;		/* server weight */
662 	atomic_t		last_weight;	/* server latest weight */
663 
664 	refcount_t		refcnt;		/* reference counter */
665 	struct ip_vs_stats      stats;          /* statistics */
666 	unsigned long		idle_start;	/* start time, jiffies */
667 
668 	/* connection counters and thresholds */
669 	atomic_t		activeconns;	/* active connections */
670 	atomic_t		inactconns;	/* inactive connections */
671 	atomic_t		persistconns;	/* persistent connections */
672 	__u32			u_threshold;	/* upper threshold */
673 	__u32			l_threshold;	/* lower threshold */
674 
675 	/* for destination cache */
676 	spinlock_t		dst_lock;	/* lock of dst_cache */
677 	struct ip_vs_dest_dst __rcu *dest_dst;	/* cached dst info */
678 
679 	/* for virtual service */
680 	struct ip_vs_service __rcu *svc;	/* service it belongs to */
681 	__u16			protocol;	/* which protocol (TCP/UDP) */
682 	__be16			vport;		/* virtual port number */
683 	union nf_inet_addr	vaddr;		/* virtual IP address */
684 	__u32			vfwmark;	/* firewall mark of service */
685 
686 	struct list_head	t_list;		/* in dest_trash */
687 	unsigned int		in_rs_table:1;	/* we are in rs_table */
688 };
689 
690 /* The scheduler object */
691 struct ip_vs_scheduler {
692 	struct list_head	n_list;		/* d-linked list head */
693 	char			*name;		/* scheduler name */
694 	atomic_t		refcnt;		/* reference counter */
695 	struct module		*module;	/* THIS_MODULE/NULL */
696 
697 	/* scheduler initializing service */
698 	int (*init_service)(struct ip_vs_service *svc);
699 	/* scheduling service finish */
700 	void (*done_service)(struct ip_vs_service *svc);
701 	/* dest is linked */
702 	int (*add_dest)(struct ip_vs_service *svc, struct ip_vs_dest *dest);
703 	/* dest is unlinked */
704 	int (*del_dest)(struct ip_vs_service *svc, struct ip_vs_dest *dest);
705 	/* dest is updated */
706 	int (*upd_dest)(struct ip_vs_service *svc, struct ip_vs_dest *dest);
707 
708 	/* selecting a server from the given service */
709 	struct ip_vs_dest* (*schedule)(struct ip_vs_service *svc,
710 				       const struct sk_buff *skb,
711 				       struct ip_vs_iphdr *iph);
712 };
713 
714 /* The persistence engine object */
715 struct ip_vs_pe {
716 	struct list_head	n_list;		/* d-linked list head */
717 	char			*name;		/* scheduler name */
718 	atomic_t		refcnt;		/* reference counter */
719 	struct module		*module;	/* THIS_MODULE/NULL */
720 
721 	/* get the connection template, if any */
722 	int (*fill_param)(struct ip_vs_conn_param *p, struct sk_buff *skb);
723 	bool (*ct_match)(const struct ip_vs_conn_param *p,
724 			 struct ip_vs_conn *ct);
725 	u32 (*hashkey_raw)(const struct ip_vs_conn_param *p, u32 initval,
726 			   bool inverse);
727 	int (*show_pe_data)(const struct ip_vs_conn *cp, char *buf);
728 	/* create connections for real-server outgoing packets */
729 	struct ip_vs_conn* (*conn_out)(struct ip_vs_service *svc,
730 				       struct ip_vs_dest *dest,
731 				       struct sk_buff *skb,
732 				       const struct ip_vs_iphdr *iph,
733 				       __be16 dport, __be16 cport);
734 };
735 
736 /* The application module object (a.k.a. app incarnation) */
737 struct ip_vs_app {
738 	struct list_head	a_list;		/* member in app list */
739 	int			type;		/* IP_VS_APP_TYPE_xxx */
740 	char			*name;		/* application module name */
741 	__u16			protocol;
742 	struct module		*module;	/* THIS_MODULE/NULL */
743 	struct list_head	incs_list;	/* list of incarnations */
744 
745 	/* members for application incarnations */
746 	struct list_head	p_list;		/* member in proto app list */
747 	struct ip_vs_app	*app;		/* its real application */
748 	__be16			port;		/* port number in net order */
749 	atomic_t		usecnt;		/* usage counter */
750 	struct rcu_head		rcu_head;
751 
752 	/* output hook: Process packet in inout direction, diff set for TCP.
753 	 * Return: 0=Error, 1=Payload Not Mangled/Mangled but checksum is ok,
754 	 *	   2=Mangled but checksum was not updated
755 	 */
756 	int (*pkt_out)(struct ip_vs_app *, struct ip_vs_conn *,
757 		       struct sk_buff *, int *diff, struct ip_vs_iphdr *ipvsh);
758 
759 	/* input hook: Process packet in outin direction, diff set for TCP.
760 	 * Return: 0=Error, 1=Payload Not Mangled/Mangled but checksum is ok,
761 	 *	   2=Mangled but checksum was not updated
762 	 */
763 	int (*pkt_in)(struct ip_vs_app *, struct ip_vs_conn *,
764 		      struct sk_buff *, int *diff, struct ip_vs_iphdr *ipvsh);
765 
766 	/* ip_vs_app initializer */
767 	int (*init_conn)(struct ip_vs_app *, struct ip_vs_conn *);
768 
769 	/* ip_vs_app finish */
770 	int (*done_conn)(struct ip_vs_app *, struct ip_vs_conn *);
771 
772 
773 	/* not used now */
774 	int (*bind_conn)(struct ip_vs_app *, struct ip_vs_conn *,
775 			 struct ip_vs_protocol *);
776 
777 	void (*unbind_conn)(struct ip_vs_app *, struct ip_vs_conn *);
778 
779 	int *			timeout_table;
780 	int *			timeouts;
781 	int			timeouts_size;
782 
783 	int (*conn_schedule)(struct sk_buff *skb, struct ip_vs_app *app,
784 			     int *verdict, struct ip_vs_conn **cpp);
785 
786 	struct ip_vs_conn *
787 	(*conn_in_get)(const struct sk_buff *skb, struct ip_vs_app *app,
788 		       const struct iphdr *iph, int inverse);
789 
790 	struct ip_vs_conn *
791 	(*conn_out_get)(const struct sk_buff *skb, struct ip_vs_app *app,
792 			const struct iphdr *iph, int inverse);
793 
794 	int (*state_transition)(struct ip_vs_conn *cp, int direction,
795 				const struct sk_buff *skb,
796 				struct ip_vs_app *app);
797 
798 	void (*timeout_change)(struct ip_vs_app *app, int flags);
799 };
800 
801 struct ipvs_master_sync_state {
802 	struct list_head	sync_queue;
803 	struct ip_vs_sync_buff	*sync_buff;
804 	unsigned long		sync_queue_len;
805 	unsigned int		sync_queue_delay;
806 	struct task_struct	*master_thread;
807 	struct delayed_work	master_wakeup_work;
808 	struct netns_ipvs	*ipvs;
809 };
810 
811 /* How much time to keep dests in trash */
812 #define IP_VS_DEST_TRASH_PERIOD		(120 * HZ)
813 
814 struct ipvs_sync_daemon_cfg {
815 	union nf_inet_addr	mcast_group;
816 	int			syncid;
817 	u16			sync_maxlen;
818 	u16			mcast_port;
819 	u8			mcast_af;
820 	u8			mcast_ttl;
821 	/* multicast interface name */
822 	char			mcast_ifn[IP_VS_IFNAME_MAXLEN];
823 };
824 
825 /* IPVS in network namespace */
826 struct netns_ipvs {
827 	int			gen;		/* Generation */
828 	int			enable;		/* enable like nf_hooks do */
829 	/* Hash table: for real service lookups */
830 	#define IP_VS_RTAB_BITS 4
831 	#define IP_VS_RTAB_SIZE (1 << IP_VS_RTAB_BITS)
832 	#define IP_VS_RTAB_MASK (IP_VS_RTAB_SIZE - 1)
833 
834 	struct hlist_head	rs_table[IP_VS_RTAB_SIZE];
835 	/* ip_vs_app */
836 	struct list_head	app_list;
837 	/* ip_vs_proto */
838 	#define IP_VS_PROTO_TAB_SIZE	32	/* must be power of 2 */
839 	struct ip_vs_proto_data *proto_data_table[IP_VS_PROTO_TAB_SIZE];
840 	/* ip_vs_proto_tcp */
841 #ifdef CONFIG_IP_VS_PROTO_TCP
842 	#define	TCP_APP_TAB_BITS	4
843 	#define	TCP_APP_TAB_SIZE	(1 << TCP_APP_TAB_BITS)
844 	#define	TCP_APP_TAB_MASK	(TCP_APP_TAB_SIZE - 1)
845 	struct list_head	tcp_apps[TCP_APP_TAB_SIZE];
846 #endif
847 	/* ip_vs_proto_udp */
848 #ifdef CONFIG_IP_VS_PROTO_UDP
849 	#define	UDP_APP_TAB_BITS	4
850 	#define	UDP_APP_TAB_SIZE	(1 << UDP_APP_TAB_BITS)
851 	#define	UDP_APP_TAB_MASK	(UDP_APP_TAB_SIZE - 1)
852 	struct list_head	udp_apps[UDP_APP_TAB_SIZE];
853 #endif
854 	/* ip_vs_proto_sctp */
855 #ifdef CONFIG_IP_VS_PROTO_SCTP
856 	#define SCTP_APP_TAB_BITS	4
857 	#define SCTP_APP_TAB_SIZE	(1 << SCTP_APP_TAB_BITS)
858 	#define SCTP_APP_TAB_MASK	(SCTP_APP_TAB_SIZE - 1)
859 	/* Hash table for SCTP application incarnations	 */
860 	struct list_head	sctp_apps[SCTP_APP_TAB_SIZE];
861 #endif
862 	/* ip_vs_conn */
863 	atomic_t		conn_count;      /* connection counter */
864 
865 	/* ip_vs_ctl */
866 	struct ip_vs_stats		tot_stats;  /* Statistics & est. */
867 
868 	int			num_services;    /* no of virtual services */
869 
870 	/* Trash for destinations */
871 	struct list_head	dest_trash;
872 	spinlock_t		dest_trash_lock;
873 	struct timer_list	dest_trash_timer; /* expiration timer */
874 	/* Service counters */
875 	atomic_t		ftpsvc_counter;
876 	atomic_t		nullsvc_counter;
877 	atomic_t		conn_out_counter;
878 
879 #ifdef CONFIG_SYSCTL
880 	/* 1/rate drop and drop-entry variables */
881 	struct delayed_work	defense_work;   /* Work handler */
882 	int			drop_rate;
883 	int			drop_counter;
884 	atomic_t		dropentry;
885 	/* locks in ctl.c */
886 	spinlock_t		dropentry_lock;  /* drop entry handling */
887 	spinlock_t		droppacket_lock; /* drop packet handling */
888 	spinlock_t		securetcp_lock;  /* state and timeout tables */
889 
890 	/* sys-ctl struct */
891 	struct ctl_table_header	*sysctl_hdr;
892 	struct ctl_table	*sysctl_tbl;
893 #endif
894 
895 	/* sysctl variables */
896 	int			sysctl_amemthresh;
897 	int			sysctl_am_droprate;
898 	int			sysctl_drop_entry;
899 	int			sysctl_drop_packet;
900 	int			sysctl_secure_tcp;
901 #ifdef CONFIG_IP_VS_NFCT
902 	int			sysctl_conntrack;
903 #endif
904 	int			sysctl_snat_reroute;
905 	int			sysctl_sync_ver;
906 	int			sysctl_sync_ports;
907 	int			sysctl_sync_persist_mode;
908 	unsigned long		sysctl_sync_qlen_max;
909 	int			sysctl_sync_sock_size;
910 	int			sysctl_cache_bypass;
911 	int			sysctl_expire_nodest_conn;
912 	int			sysctl_sloppy_tcp;
913 	int			sysctl_sloppy_sctp;
914 	int			sysctl_expire_quiescent_template;
915 	int			sysctl_sync_threshold[2];
916 	unsigned int		sysctl_sync_refresh_period;
917 	int			sysctl_sync_retries;
918 	int			sysctl_nat_icmp_send;
919 	int			sysctl_pmtu_disc;
920 	int			sysctl_backup_only;
921 	int			sysctl_conn_reuse_mode;
922 	int			sysctl_schedule_icmp;
923 	int			sysctl_ignore_tunneled;
924 
925 	/* ip_vs_lblc */
926 	int			sysctl_lblc_expiration;
927 	struct ctl_table_header	*lblc_ctl_header;
928 	struct ctl_table	*lblc_ctl_table;
929 	/* ip_vs_lblcr */
930 	int			sysctl_lblcr_expiration;
931 	struct ctl_table_header	*lblcr_ctl_header;
932 	struct ctl_table	*lblcr_ctl_table;
933 	/* ip_vs_est */
934 	struct list_head	est_list;	/* estimator list */
935 	spinlock_t		est_lock;
936 	struct timer_list	est_timer;	/* Estimation timer */
937 	/* ip_vs_sync */
938 	spinlock_t		sync_lock;
939 	struct ipvs_master_sync_state *ms;
940 	spinlock_t		sync_buff_lock;
941 	struct task_struct	**backup_threads;
942 	int			threads_mask;
943 	volatile int		sync_state;
944 	struct mutex		sync_mutex;
945 	struct ipvs_sync_daemon_cfg	mcfg;	/* Master Configuration */
946 	struct ipvs_sync_daemon_cfg	bcfg;	/* Backup Configuration */
947 	/* net name space ptr */
948 	struct net		*net;            /* Needed by timer routines */
949 	/* Number of heterogeneous destinations, needed becaus heterogeneous
950 	 * are not supported when synchronization is enabled.
951 	 */
952 	unsigned int		mixed_address_family_dests;
953 };
954 
955 #define DEFAULT_SYNC_THRESHOLD	3
956 #define DEFAULT_SYNC_PERIOD	50
957 #define DEFAULT_SYNC_VER	1
958 #define DEFAULT_SLOPPY_TCP	0
959 #define DEFAULT_SLOPPY_SCTP	0
960 #define DEFAULT_SYNC_REFRESH_PERIOD	(0U * HZ)
961 #define DEFAULT_SYNC_RETRIES		0
962 #define IPVS_SYNC_WAKEUP_RATE	8
963 #define IPVS_SYNC_QLEN_MAX	(IPVS_SYNC_WAKEUP_RATE * 4)
964 #define IPVS_SYNC_SEND_DELAY	(HZ / 50)
965 #define IPVS_SYNC_CHECK_PERIOD	HZ
966 #define IPVS_SYNC_FLUSH_TIME	(HZ * 2)
967 #define IPVS_SYNC_PORTS_MAX	(1 << 6)
968 
969 #ifdef CONFIG_SYSCTL
970 
971 static inline int sysctl_sync_threshold(struct netns_ipvs *ipvs)
972 {
973 	return ipvs->sysctl_sync_threshold[0];
974 }
975 
976 static inline int sysctl_sync_period(struct netns_ipvs *ipvs)
977 {
978 	return READ_ONCE(ipvs->sysctl_sync_threshold[1]);
979 }
980 
981 static inline unsigned int sysctl_sync_refresh_period(struct netns_ipvs *ipvs)
982 {
983 	return READ_ONCE(ipvs->sysctl_sync_refresh_period);
984 }
985 
986 static inline int sysctl_sync_retries(struct netns_ipvs *ipvs)
987 {
988 	return ipvs->sysctl_sync_retries;
989 }
990 
991 static inline int sysctl_sync_ver(struct netns_ipvs *ipvs)
992 {
993 	return ipvs->sysctl_sync_ver;
994 }
995 
996 static inline int sysctl_sloppy_tcp(struct netns_ipvs *ipvs)
997 {
998 	return ipvs->sysctl_sloppy_tcp;
999 }
1000 
1001 static inline int sysctl_sloppy_sctp(struct netns_ipvs *ipvs)
1002 {
1003 	return ipvs->sysctl_sloppy_sctp;
1004 }
1005 
1006 static inline int sysctl_sync_ports(struct netns_ipvs *ipvs)
1007 {
1008 	return READ_ONCE(ipvs->sysctl_sync_ports);
1009 }
1010 
1011 static inline int sysctl_sync_persist_mode(struct netns_ipvs *ipvs)
1012 {
1013 	return ipvs->sysctl_sync_persist_mode;
1014 }
1015 
1016 static inline unsigned long sysctl_sync_qlen_max(struct netns_ipvs *ipvs)
1017 {
1018 	return ipvs->sysctl_sync_qlen_max;
1019 }
1020 
1021 static inline int sysctl_sync_sock_size(struct netns_ipvs *ipvs)
1022 {
1023 	return ipvs->sysctl_sync_sock_size;
1024 }
1025 
1026 static inline int sysctl_pmtu_disc(struct netns_ipvs *ipvs)
1027 {
1028 	return ipvs->sysctl_pmtu_disc;
1029 }
1030 
1031 static inline int sysctl_backup_only(struct netns_ipvs *ipvs)
1032 {
1033 	return ipvs->sync_state & IP_VS_STATE_BACKUP &&
1034 	       ipvs->sysctl_backup_only;
1035 }
1036 
1037 static inline int sysctl_conn_reuse_mode(struct netns_ipvs *ipvs)
1038 {
1039 	return ipvs->sysctl_conn_reuse_mode;
1040 }
1041 
1042 static inline int sysctl_schedule_icmp(struct netns_ipvs *ipvs)
1043 {
1044 	return ipvs->sysctl_schedule_icmp;
1045 }
1046 
1047 static inline int sysctl_ignore_tunneled(struct netns_ipvs *ipvs)
1048 {
1049 	return ipvs->sysctl_ignore_tunneled;
1050 }
1051 
1052 static inline int sysctl_cache_bypass(struct netns_ipvs *ipvs)
1053 {
1054 	return ipvs->sysctl_cache_bypass;
1055 }
1056 
1057 #else
1058 
1059 static inline int sysctl_sync_threshold(struct netns_ipvs *ipvs)
1060 {
1061 	return DEFAULT_SYNC_THRESHOLD;
1062 }
1063 
1064 static inline int sysctl_sync_period(struct netns_ipvs *ipvs)
1065 {
1066 	return DEFAULT_SYNC_PERIOD;
1067 }
1068 
1069 static inline unsigned int sysctl_sync_refresh_period(struct netns_ipvs *ipvs)
1070 {
1071 	return DEFAULT_SYNC_REFRESH_PERIOD;
1072 }
1073 
1074 static inline int sysctl_sync_retries(struct netns_ipvs *ipvs)
1075 {
1076 	return DEFAULT_SYNC_RETRIES & 3;
1077 }
1078 
1079 static inline int sysctl_sync_ver(struct netns_ipvs *ipvs)
1080 {
1081 	return DEFAULT_SYNC_VER;
1082 }
1083 
1084 static inline int sysctl_sloppy_tcp(struct netns_ipvs *ipvs)
1085 {
1086 	return DEFAULT_SLOPPY_TCP;
1087 }
1088 
1089 static inline int sysctl_sloppy_sctp(struct netns_ipvs *ipvs)
1090 {
1091 	return DEFAULT_SLOPPY_SCTP;
1092 }
1093 
1094 static inline int sysctl_sync_ports(struct netns_ipvs *ipvs)
1095 {
1096 	return 1;
1097 }
1098 
1099 static inline int sysctl_sync_persist_mode(struct netns_ipvs *ipvs)
1100 {
1101 	return 0;
1102 }
1103 
1104 static inline unsigned long sysctl_sync_qlen_max(struct netns_ipvs *ipvs)
1105 {
1106 	return IPVS_SYNC_QLEN_MAX;
1107 }
1108 
1109 static inline int sysctl_sync_sock_size(struct netns_ipvs *ipvs)
1110 {
1111 	return 0;
1112 }
1113 
1114 static inline int sysctl_pmtu_disc(struct netns_ipvs *ipvs)
1115 {
1116 	return 1;
1117 }
1118 
1119 static inline int sysctl_backup_only(struct netns_ipvs *ipvs)
1120 {
1121 	return 0;
1122 }
1123 
1124 static inline int sysctl_conn_reuse_mode(struct netns_ipvs *ipvs)
1125 {
1126 	return 1;
1127 }
1128 
1129 static inline int sysctl_schedule_icmp(struct netns_ipvs *ipvs)
1130 {
1131 	return 0;
1132 }
1133 
1134 static inline int sysctl_ignore_tunneled(struct netns_ipvs *ipvs)
1135 {
1136 	return 0;
1137 }
1138 
1139 static inline int sysctl_cache_bypass(struct netns_ipvs *ipvs)
1140 {
1141 	return 0;
1142 }
1143 
1144 #endif
1145 
1146 /* IPVS core functions
1147  * (from ip_vs_core.c)
1148  */
1149 const char *ip_vs_proto_name(unsigned int proto);
1150 void ip_vs_init_hash_table(struct list_head *table, int rows);
1151 struct ip_vs_conn *ip_vs_new_conn_out(struct ip_vs_service *svc,
1152 				      struct ip_vs_dest *dest,
1153 				      struct sk_buff *skb,
1154 				      const struct ip_vs_iphdr *iph,
1155 				      __be16 dport,
1156 				      __be16 cport);
1157 #define IP_VS_INIT_HASH_TABLE(t) ip_vs_init_hash_table((t), ARRAY_SIZE((t)))
1158 
1159 #define IP_VS_APP_TYPE_FTP	1
1160 
1161 /* ip_vs_conn handling functions
1162  * (from ip_vs_conn.c)
1163  */
1164 enum {
1165 	IP_VS_DIR_INPUT = 0,
1166 	IP_VS_DIR_OUTPUT,
1167 	IP_VS_DIR_INPUT_ONLY,
1168 	IP_VS_DIR_LAST,
1169 };
1170 
1171 static inline void ip_vs_conn_fill_param(struct netns_ipvs *ipvs, int af, int protocol,
1172 					 const union nf_inet_addr *caddr,
1173 					 __be16 cport,
1174 					 const union nf_inet_addr *vaddr,
1175 					 __be16 vport,
1176 					 struct ip_vs_conn_param *p)
1177 {
1178 	p->ipvs = ipvs;
1179 	p->af = af;
1180 	p->protocol = protocol;
1181 	p->caddr = caddr;
1182 	p->cport = cport;
1183 	p->vaddr = vaddr;
1184 	p->vport = vport;
1185 	p->pe = NULL;
1186 	p->pe_data = NULL;
1187 }
1188 
1189 struct ip_vs_conn *ip_vs_conn_in_get(const struct ip_vs_conn_param *p);
1190 struct ip_vs_conn *ip_vs_ct_in_get(const struct ip_vs_conn_param *p);
1191 
1192 struct ip_vs_conn * ip_vs_conn_in_get_proto(struct netns_ipvs *ipvs, int af,
1193 					    const struct sk_buff *skb,
1194 					    const struct ip_vs_iphdr *iph);
1195 
1196 struct ip_vs_conn *ip_vs_conn_out_get(const struct ip_vs_conn_param *p);
1197 
1198 struct ip_vs_conn * ip_vs_conn_out_get_proto(struct netns_ipvs *ipvs, int af,
1199 					     const struct sk_buff *skb,
1200 					     const struct ip_vs_iphdr *iph);
1201 
1202 /* Get reference to gain full access to conn.
1203  * By default, RCU read-side critical sections have access only to
1204  * conn fields and its PE data, see ip_vs_conn_rcu_free() for reference.
1205  */
1206 static inline bool __ip_vs_conn_get(struct ip_vs_conn *cp)
1207 {
1208 	return refcount_inc_not_zero(&cp->refcnt);
1209 }
1210 
1211 /* put back the conn without restarting its timer */
1212 static inline void __ip_vs_conn_put(struct ip_vs_conn *cp)
1213 {
1214 	smp_mb__before_atomic();
1215 	refcount_dec(&cp->refcnt);
1216 }
1217 void ip_vs_conn_put(struct ip_vs_conn *cp);
1218 void ip_vs_conn_fill_cport(struct ip_vs_conn *cp, __be16 cport);
1219 
1220 struct ip_vs_conn *ip_vs_conn_new(const struct ip_vs_conn_param *p, int dest_af,
1221 				  const union nf_inet_addr *daddr,
1222 				  __be16 dport, unsigned int flags,
1223 				  struct ip_vs_dest *dest, __u32 fwmark);
1224 void ip_vs_conn_expire_now(struct ip_vs_conn *cp);
1225 
1226 const char *ip_vs_state_name(const struct ip_vs_conn *cp);
1227 
1228 void ip_vs_tcp_conn_listen(struct ip_vs_conn *cp);
1229 int ip_vs_check_template(struct ip_vs_conn *ct, struct ip_vs_dest *cdest);
1230 void ip_vs_random_dropentry(struct netns_ipvs *ipvs);
1231 int ip_vs_conn_init(void);
1232 void ip_vs_conn_cleanup(void);
1233 
1234 static inline void ip_vs_control_del(struct ip_vs_conn *cp)
1235 {
1236 	struct ip_vs_conn *ctl_cp = cp->control;
1237 	if (!ctl_cp) {
1238 		IP_VS_ERR_BUF("request control DEL for uncontrolled: "
1239 			      "%s:%d to %s:%d\n",
1240 			      IP_VS_DBG_ADDR(cp->af, &cp->caddr),
1241 			      ntohs(cp->cport),
1242 			      IP_VS_DBG_ADDR(cp->af, &cp->vaddr),
1243 			      ntohs(cp->vport));
1244 
1245 		return;
1246 	}
1247 
1248 	IP_VS_DBG_BUF(7, "DELeting control for: "
1249 		      "cp.dst=%s:%d ctl_cp.dst=%s:%d\n",
1250 		      IP_VS_DBG_ADDR(cp->af, &cp->caddr),
1251 		      ntohs(cp->cport),
1252 		      IP_VS_DBG_ADDR(cp->af, &ctl_cp->caddr),
1253 		      ntohs(ctl_cp->cport));
1254 
1255 	cp->control = NULL;
1256 	if (atomic_read(&ctl_cp->n_control) == 0) {
1257 		IP_VS_ERR_BUF("BUG control DEL with n=0 : "
1258 			      "%s:%d to %s:%d\n",
1259 			      IP_VS_DBG_ADDR(cp->af, &cp->caddr),
1260 			      ntohs(cp->cport),
1261 			      IP_VS_DBG_ADDR(cp->af, &cp->vaddr),
1262 			      ntohs(cp->vport));
1263 
1264 		return;
1265 	}
1266 	atomic_dec(&ctl_cp->n_control);
1267 }
1268 
1269 static inline void
1270 ip_vs_control_add(struct ip_vs_conn *cp, struct ip_vs_conn *ctl_cp)
1271 {
1272 	if (cp->control) {
1273 		IP_VS_ERR_BUF("request control ADD for already controlled: "
1274 			      "%s:%d to %s:%d\n",
1275 			      IP_VS_DBG_ADDR(cp->af, &cp->caddr),
1276 			      ntohs(cp->cport),
1277 			      IP_VS_DBG_ADDR(cp->af, &cp->vaddr),
1278 			      ntohs(cp->vport));
1279 
1280 		ip_vs_control_del(cp);
1281 	}
1282 
1283 	IP_VS_DBG_BUF(7, "ADDing control for: "
1284 		      "cp.dst=%s:%d ctl_cp.dst=%s:%d\n",
1285 		      IP_VS_DBG_ADDR(cp->af, &cp->caddr),
1286 		      ntohs(cp->cport),
1287 		      IP_VS_DBG_ADDR(cp->af, &ctl_cp->caddr),
1288 		      ntohs(ctl_cp->cport));
1289 
1290 	cp->control = ctl_cp;
1291 	atomic_inc(&ctl_cp->n_control);
1292 }
1293 
1294 /* Mark our template as assured */
1295 static inline void
1296 ip_vs_control_assure_ct(struct ip_vs_conn *cp)
1297 {
1298 	struct ip_vs_conn *ct = cp->control;
1299 
1300 	if (ct && !(ct->state & IP_VS_CTPL_S_ASSURED) &&
1301 	    (ct->flags & IP_VS_CONN_F_TEMPLATE))
1302 		ct->state |= IP_VS_CTPL_S_ASSURED;
1303 }
1304 
1305 /* IPVS netns init & cleanup functions */
1306 int ip_vs_estimator_net_init(struct netns_ipvs *ipvs);
1307 int ip_vs_control_net_init(struct netns_ipvs *ipvs);
1308 int ip_vs_protocol_net_init(struct netns_ipvs *ipvs);
1309 int ip_vs_app_net_init(struct netns_ipvs *ipvs);
1310 int ip_vs_conn_net_init(struct netns_ipvs *ipvs);
1311 int ip_vs_sync_net_init(struct netns_ipvs *ipvs);
1312 void ip_vs_conn_net_cleanup(struct netns_ipvs *ipvs);
1313 void ip_vs_app_net_cleanup(struct netns_ipvs *ipvs);
1314 void ip_vs_protocol_net_cleanup(struct netns_ipvs *ipvs);
1315 void ip_vs_control_net_cleanup(struct netns_ipvs *ipvs);
1316 void ip_vs_estimator_net_cleanup(struct netns_ipvs *ipvs);
1317 void ip_vs_sync_net_cleanup(struct netns_ipvs *ipvs);
1318 void ip_vs_service_net_cleanup(struct netns_ipvs *ipvs);
1319 
1320 /* IPVS application functions
1321  * (from ip_vs_app.c)
1322  */
1323 #define IP_VS_APP_MAX_PORTS  8
1324 struct ip_vs_app *register_ip_vs_app(struct netns_ipvs *ipvs, struct ip_vs_app *app);
1325 void unregister_ip_vs_app(struct netns_ipvs *ipvs, struct ip_vs_app *app);
1326 int ip_vs_bind_app(struct ip_vs_conn *cp, struct ip_vs_protocol *pp);
1327 void ip_vs_unbind_app(struct ip_vs_conn *cp);
1328 int register_ip_vs_app_inc(struct netns_ipvs *ipvs, struct ip_vs_app *app, __u16 proto,
1329 			   __u16 port);
1330 int ip_vs_app_inc_get(struct ip_vs_app *inc);
1331 void ip_vs_app_inc_put(struct ip_vs_app *inc);
1332 
1333 int ip_vs_app_pkt_out(struct ip_vs_conn *, struct sk_buff *skb,
1334 		      struct ip_vs_iphdr *ipvsh);
1335 int ip_vs_app_pkt_in(struct ip_vs_conn *, struct sk_buff *skb,
1336 		     struct ip_vs_iphdr *ipvsh);
1337 
1338 int register_ip_vs_pe(struct ip_vs_pe *pe);
1339 int unregister_ip_vs_pe(struct ip_vs_pe *pe);
1340 struct ip_vs_pe *ip_vs_pe_getbyname(const char *name);
1341 struct ip_vs_pe *__ip_vs_pe_getbyname(const char *pe_name);
1342 
1343 /* Use a #define to avoid all of module.h just for these trivial ops */
1344 #define ip_vs_pe_get(pe)			\
1345 	if (pe && pe->module)			\
1346 		__module_get(pe->module);
1347 
1348 #define ip_vs_pe_put(pe)			\
1349 	if (pe && pe->module)			\
1350 		module_put(pe->module);
1351 
1352 /* IPVS protocol functions (from ip_vs_proto.c) */
1353 int ip_vs_protocol_init(void);
1354 void ip_vs_protocol_cleanup(void);
1355 void ip_vs_protocol_timeout_change(struct netns_ipvs *ipvs, int flags);
1356 int *ip_vs_create_timeout_table(int *table, int size);
1357 void ip_vs_tcpudp_debug_packet(int af, struct ip_vs_protocol *pp,
1358 			       const struct sk_buff *skb, int offset,
1359 			       const char *msg);
1360 
1361 extern struct ip_vs_protocol ip_vs_protocol_tcp;
1362 extern struct ip_vs_protocol ip_vs_protocol_udp;
1363 extern struct ip_vs_protocol ip_vs_protocol_icmp;
1364 extern struct ip_vs_protocol ip_vs_protocol_esp;
1365 extern struct ip_vs_protocol ip_vs_protocol_ah;
1366 extern struct ip_vs_protocol ip_vs_protocol_sctp;
1367 
1368 /* Registering/unregistering scheduler functions
1369  * (from ip_vs_sched.c)
1370  */
1371 int register_ip_vs_scheduler(struct ip_vs_scheduler *scheduler);
1372 int unregister_ip_vs_scheduler(struct ip_vs_scheduler *scheduler);
1373 int ip_vs_bind_scheduler(struct ip_vs_service *svc,
1374 			 struct ip_vs_scheduler *scheduler);
1375 void ip_vs_unbind_scheduler(struct ip_vs_service *svc,
1376 			    struct ip_vs_scheduler *sched);
1377 struct ip_vs_scheduler *ip_vs_scheduler_get(const char *sched_name);
1378 void ip_vs_scheduler_put(struct ip_vs_scheduler *scheduler);
1379 struct ip_vs_conn *
1380 ip_vs_schedule(struct ip_vs_service *svc, struct sk_buff *skb,
1381 	       struct ip_vs_proto_data *pd, int *ignored,
1382 	       struct ip_vs_iphdr *iph);
1383 int ip_vs_leave(struct ip_vs_service *svc, struct sk_buff *skb,
1384 		struct ip_vs_proto_data *pd, struct ip_vs_iphdr *iph);
1385 
1386 void ip_vs_scheduler_err(struct ip_vs_service *svc, const char *msg);
1387 
1388 /* IPVS control data and functions (from ip_vs_ctl.c) */
1389 extern struct ip_vs_stats ip_vs_stats;
1390 extern int sysctl_ip_vs_sync_ver;
1391 
1392 struct ip_vs_service *
1393 ip_vs_service_find(struct netns_ipvs *ipvs, int af, __u32 fwmark, __u16 protocol,
1394 		  const union nf_inet_addr *vaddr, __be16 vport);
1395 
1396 bool ip_vs_has_real_service(struct netns_ipvs *ipvs, int af, __u16 protocol,
1397 			    const union nf_inet_addr *daddr, __be16 dport);
1398 
1399 struct ip_vs_dest *
1400 ip_vs_find_real_service(struct netns_ipvs *ipvs, int af, __u16 protocol,
1401 			const union nf_inet_addr *daddr, __be16 dport);
1402 
1403 int ip_vs_use_count_inc(void);
1404 void ip_vs_use_count_dec(void);
1405 int ip_vs_register_nl_ioctl(void);
1406 void ip_vs_unregister_nl_ioctl(void);
1407 int ip_vs_control_init(void);
1408 void ip_vs_control_cleanup(void);
1409 struct ip_vs_dest *
1410 ip_vs_find_dest(struct netns_ipvs *ipvs, int svc_af, int dest_af,
1411 		const union nf_inet_addr *daddr, __be16 dport,
1412 		const union nf_inet_addr *vaddr, __be16 vport,
1413 		__u16 protocol, __u32 fwmark, __u32 flags);
1414 void ip_vs_try_bind_dest(struct ip_vs_conn *cp);
1415 
1416 static inline void ip_vs_dest_hold(struct ip_vs_dest *dest)
1417 {
1418 	refcount_inc(&dest->refcnt);
1419 }
1420 
1421 static inline void ip_vs_dest_put(struct ip_vs_dest *dest)
1422 {
1423 	smp_mb__before_atomic();
1424 	refcount_dec(&dest->refcnt);
1425 }
1426 
1427 static inline void ip_vs_dest_put_and_free(struct ip_vs_dest *dest)
1428 {
1429 	if (refcount_dec_and_test(&dest->refcnt))
1430 		kfree(dest);
1431 }
1432 
1433 /* IPVS sync daemon data and function prototypes
1434  * (from ip_vs_sync.c)
1435  */
1436 int start_sync_thread(struct netns_ipvs *ipvs, struct ipvs_sync_daemon_cfg *cfg,
1437 		      int state);
1438 int stop_sync_thread(struct netns_ipvs *ipvs, int state);
1439 void ip_vs_sync_conn(struct netns_ipvs *ipvs, struct ip_vs_conn *cp, int pkts);
1440 
1441 /* IPVS rate estimator prototypes (from ip_vs_est.c) */
1442 void ip_vs_start_estimator(struct netns_ipvs *ipvs, struct ip_vs_stats *stats);
1443 void ip_vs_stop_estimator(struct netns_ipvs *ipvs, struct ip_vs_stats *stats);
1444 void ip_vs_zero_estimator(struct ip_vs_stats *stats);
1445 void ip_vs_read_estimator(struct ip_vs_kstats *dst, struct ip_vs_stats *stats);
1446 
1447 /* Various IPVS packet transmitters (from ip_vs_xmit.c) */
1448 int ip_vs_null_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_bypass_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_nat_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_tunnel_xmit(struct sk_buff *skb, struct ip_vs_conn *cp,
1455 		      struct ip_vs_protocol *pp, struct ip_vs_iphdr *iph);
1456 int ip_vs_dr_xmit(struct sk_buff *skb, struct ip_vs_conn *cp,
1457 		  struct ip_vs_protocol *pp, struct ip_vs_iphdr *iph);
1458 int ip_vs_icmp_xmit(struct sk_buff *skb, struct ip_vs_conn *cp,
1459 		    struct ip_vs_protocol *pp, int offset,
1460 		    unsigned int hooknum, struct ip_vs_iphdr *iph);
1461 void ip_vs_dest_dst_rcu_free(struct rcu_head *head);
1462 
1463 #ifdef CONFIG_IP_VS_IPV6
1464 int ip_vs_bypass_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_nat_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_tunnel_xmit_v6(struct sk_buff *skb, struct ip_vs_conn *cp,
1469 			 struct ip_vs_protocol *pp, struct ip_vs_iphdr *iph);
1470 int ip_vs_dr_xmit_v6(struct sk_buff *skb, struct ip_vs_conn *cp,
1471 		     struct ip_vs_protocol *pp, struct ip_vs_iphdr *iph);
1472 int ip_vs_icmp_xmit_v6(struct sk_buff *skb, struct ip_vs_conn *cp,
1473 		       struct ip_vs_protocol *pp, int offset,
1474 		       unsigned int hooknum, struct ip_vs_iphdr *iph);
1475 #endif
1476 
1477 #ifdef CONFIG_SYSCTL
1478 /* This is a simple mechanism to ignore packets when
1479  * we are loaded. Just set ip_vs_drop_rate to 'n' and
1480  * we start to drop 1/rate of the packets
1481  */
1482 static inline int ip_vs_todrop(struct netns_ipvs *ipvs)
1483 {
1484 	if (!ipvs->drop_rate)
1485 		return 0;
1486 	if (--ipvs->drop_counter > 0)
1487 		return 0;
1488 	ipvs->drop_counter = ipvs->drop_rate;
1489 	return 1;
1490 }
1491 #else
1492 static inline int ip_vs_todrop(struct netns_ipvs *ipvs) { return 0; }
1493 #endif
1494 
1495 /* ip_vs_fwd_tag returns the forwarding tag of the connection */
1496 #define IP_VS_FWD_METHOD(cp)  (cp->flags & IP_VS_CONN_F_FWD_MASK)
1497 
1498 static inline char ip_vs_fwd_tag(struct ip_vs_conn *cp)
1499 {
1500 	char fwd;
1501 
1502 	switch (IP_VS_FWD_METHOD(cp)) {
1503 	case IP_VS_CONN_F_MASQ:
1504 		fwd = 'M'; break;
1505 	case IP_VS_CONN_F_LOCALNODE:
1506 		fwd = 'L'; break;
1507 	case IP_VS_CONN_F_TUNNEL:
1508 		fwd = 'T'; break;
1509 	case IP_VS_CONN_F_DROUTE:
1510 		fwd = 'R'; break;
1511 	case IP_VS_CONN_F_BYPASS:
1512 		fwd = 'B'; break;
1513 	default:
1514 		fwd = '?'; break;
1515 	}
1516 	return fwd;
1517 }
1518 
1519 void ip_vs_nat_icmp(struct sk_buff *skb, struct ip_vs_protocol *pp,
1520 		    struct ip_vs_conn *cp, int dir);
1521 
1522 #ifdef CONFIG_IP_VS_IPV6
1523 void ip_vs_nat_icmp_v6(struct sk_buff *skb, struct ip_vs_protocol *pp,
1524 		       struct ip_vs_conn *cp, int dir);
1525 #endif
1526 
1527 __sum16 ip_vs_checksum_complete(struct sk_buff *skb, int offset);
1528 
1529 static inline __wsum ip_vs_check_diff4(__be32 old, __be32 new, __wsum oldsum)
1530 {
1531 	__be32 diff[2] = { ~old, new };
1532 
1533 	return csum_partial(diff, sizeof(diff), oldsum);
1534 }
1535 
1536 #ifdef CONFIG_IP_VS_IPV6
1537 static inline __wsum ip_vs_check_diff16(const __be32 *old, const __be32 *new,
1538 					__wsum oldsum)
1539 {
1540 	__be32 diff[8] = { ~old[3], ~old[2], ~old[1], ~old[0],
1541 			    new[3],  new[2],  new[1],  new[0] };
1542 
1543 	return csum_partial(diff, sizeof(diff), oldsum);
1544 }
1545 #endif
1546 
1547 static inline __wsum ip_vs_check_diff2(__be16 old, __be16 new, __wsum oldsum)
1548 {
1549 	__be16 diff[2] = { ~old, new };
1550 
1551 	return csum_partial(diff, sizeof(diff), oldsum);
1552 }
1553 
1554 /* Forget current conntrack (unconfirmed) and attach notrack entry */
1555 static inline void ip_vs_notrack(struct sk_buff *skb)
1556 {
1557 #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
1558 	enum ip_conntrack_info ctinfo;
1559 	struct nf_conn *ct = nf_ct_get(skb, &ctinfo);
1560 
1561 	if (ct) {
1562 		nf_conntrack_put(&ct->ct_general);
1563 		nf_ct_set(skb, NULL, IP_CT_UNTRACKED);
1564 	}
1565 #endif
1566 }
1567 
1568 #ifdef CONFIG_IP_VS_NFCT
1569 /* Netfilter connection tracking
1570  * (from ip_vs_nfct.c)
1571  */
1572 static inline int ip_vs_conntrack_enabled(struct netns_ipvs *ipvs)
1573 {
1574 #ifdef CONFIG_SYSCTL
1575 	return ipvs->sysctl_conntrack;
1576 #else
1577 	return 0;
1578 #endif
1579 }
1580 
1581 void ip_vs_update_conntrack(struct sk_buff *skb, struct ip_vs_conn *cp,
1582 			    int outin);
1583 int ip_vs_confirm_conntrack(struct sk_buff *skb);
1584 void ip_vs_nfct_expect_related(struct sk_buff *skb, struct nf_conn *ct,
1585 			       struct ip_vs_conn *cp, u_int8_t proto,
1586 			       const __be16 port, int from_rs);
1587 void ip_vs_conn_drop_conntrack(struct ip_vs_conn *cp);
1588 
1589 #else
1590 
1591 static inline int ip_vs_conntrack_enabled(struct netns_ipvs *ipvs)
1592 {
1593 	return 0;
1594 }
1595 
1596 static inline void ip_vs_update_conntrack(struct sk_buff *skb,
1597 					  struct ip_vs_conn *cp, int outin)
1598 {
1599 }
1600 
1601 static inline int ip_vs_confirm_conntrack(struct sk_buff *skb)
1602 {
1603 	return NF_ACCEPT;
1604 }
1605 
1606 static inline void ip_vs_conn_drop_conntrack(struct ip_vs_conn *cp)
1607 {
1608 }
1609 #endif /* CONFIG_IP_VS_NFCT */
1610 
1611 /* Really using conntrack? */
1612 static inline bool ip_vs_conn_uses_conntrack(struct ip_vs_conn *cp,
1613 					     struct sk_buff *skb)
1614 {
1615 #ifdef CONFIG_IP_VS_NFCT
1616 	enum ip_conntrack_info ctinfo;
1617 	struct nf_conn *ct;
1618 
1619 	if (!(cp->flags & IP_VS_CONN_F_NFCT))
1620 		return false;
1621 	ct = nf_ct_get(skb, &ctinfo);
1622 	if (ct)
1623 		return true;
1624 #endif
1625 	return false;
1626 }
1627 
1628 static inline int ip_vs_register_conntrack(struct ip_vs_service *svc)
1629 {
1630 #if IS_ENABLED(CONFIG_NF_CONNTRACK)
1631 	int afmask = (svc->af == AF_INET6) ? 2 : 1;
1632 	int ret = 0;
1633 
1634 	if (!(svc->conntrack_afmask & afmask)) {
1635 		ret = nf_ct_netns_get(svc->ipvs->net, svc->af);
1636 		if (ret >= 0)
1637 			svc->conntrack_afmask |= afmask;
1638 	}
1639 	return ret;
1640 #else
1641 	return 0;
1642 #endif
1643 }
1644 
1645 static inline void ip_vs_unregister_conntrack(struct ip_vs_service *svc)
1646 {
1647 #if IS_ENABLED(CONFIG_NF_CONNTRACK)
1648 	int afmask = (svc->af == AF_INET6) ? 2 : 1;
1649 
1650 	if (svc->conntrack_afmask & afmask) {
1651 		nf_ct_netns_put(svc->ipvs->net, svc->af);
1652 		svc->conntrack_afmask &= ~afmask;
1653 	}
1654 #endif
1655 }
1656 
1657 static inline int
1658 ip_vs_dest_conn_overhead(struct ip_vs_dest *dest)
1659 {
1660 	/* We think the overhead of processing active connections is 256
1661 	 * times higher than that of inactive connections in average. (This
1662 	 * 256 times might not be accurate, we will change it later) We
1663 	 * use the following formula to estimate the overhead now:
1664 	 *		  dest->activeconns*256 + dest->inactconns
1665 	 */
1666 	return (atomic_read(&dest->activeconns) << 8) +
1667 		atomic_read(&dest->inactconns);
1668 }
1669 
1670 #endif	/* _NET_IP_VS_H */
1671