xref: /openbmc/linux/include/net/ip_vs.h (revision 87c2ce3b)
1 /*
2  *      IP Virtual Server
3  *      data structure and functionality definitions
4  */
5 
6 #ifndef _IP_VS_H
7 #define _IP_VS_H
8 
9 #include <asm/types.h>		/* For __uXX types */
10 
11 #define IP_VS_VERSION_CODE	0x010201
12 #define NVERSION(version)			\
13 	(version >> 16) & 0xFF,			\
14 	(version >> 8) & 0xFF,			\
15 	version & 0xFF
16 
17 /*
18  *      Virtual Service Flags
19  */
20 #define IP_VS_SVC_F_PERSISTENT	0x0001		/* persistent port */
21 #define IP_VS_SVC_F_HASHED	0x0002		/* hashed entry */
22 
23 /*
24  *      Destination Server Flags
25  */
26 #define IP_VS_DEST_F_AVAILABLE	0x0001		/* server is available */
27 #define IP_VS_DEST_F_OVERLOAD	0x0002		/* server is overloaded */
28 
29 /*
30  *      IPVS sync daemon states
31  */
32 #define IP_VS_STATE_NONE	0x0000		/* daemon is stopped */
33 #define IP_VS_STATE_MASTER	0x0001		/* started as master */
34 #define IP_VS_STATE_BACKUP	0x0002		/* started as backup */
35 
36 /*
37  *      IPVS socket options
38  */
39 #define IP_VS_BASE_CTL		(64+1024+64)		/* base */
40 
41 #define IP_VS_SO_SET_NONE	IP_VS_BASE_CTL		/* just peek */
42 #define IP_VS_SO_SET_INSERT	(IP_VS_BASE_CTL+1)
43 #define IP_VS_SO_SET_ADD	(IP_VS_BASE_CTL+2)
44 #define IP_VS_SO_SET_EDIT	(IP_VS_BASE_CTL+3)
45 #define IP_VS_SO_SET_DEL	(IP_VS_BASE_CTL+4)
46 #define IP_VS_SO_SET_FLUSH	(IP_VS_BASE_CTL+5)
47 #define IP_VS_SO_SET_LIST	(IP_VS_BASE_CTL+6)
48 #define IP_VS_SO_SET_ADDDEST	(IP_VS_BASE_CTL+7)
49 #define IP_VS_SO_SET_DELDEST	(IP_VS_BASE_CTL+8)
50 #define IP_VS_SO_SET_EDITDEST	(IP_VS_BASE_CTL+9)
51 #define IP_VS_SO_SET_TIMEOUT	(IP_VS_BASE_CTL+10)
52 #define IP_VS_SO_SET_STARTDAEMON (IP_VS_BASE_CTL+11)
53 #define IP_VS_SO_SET_STOPDAEMON (IP_VS_BASE_CTL+12)
54 #define IP_VS_SO_SET_RESTORE    (IP_VS_BASE_CTL+13)
55 #define IP_VS_SO_SET_SAVE       (IP_VS_BASE_CTL+14)
56 #define IP_VS_SO_SET_ZERO	(IP_VS_BASE_CTL+15)
57 #define IP_VS_SO_SET_MAX	IP_VS_SO_SET_ZERO
58 
59 #define IP_VS_SO_GET_VERSION	IP_VS_BASE_CTL
60 #define IP_VS_SO_GET_INFO	(IP_VS_BASE_CTL+1)
61 #define IP_VS_SO_GET_SERVICES	(IP_VS_BASE_CTL+2)
62 #define IP_VS_SO_GET_SERVICE	(IP_VS_BASE_CTL+3)
63 #define IP_VS_SO_GET_DESTS	(IP_VS_BASE_CTL+4)
64 #define IP_VS_SO_GET_DEST	(IP_VS_BASE_CTL+5)	/* not used now */
65 #define IP_VS_SO_GET_TIMEOUT	(IP_VS_BASE_CTL+6)
66 #define IP_VS_SO_GET_DAEMON	(IP_VS_BASE_CTL+7)
67 #define IP_VS_SO_GET_MAX	IP_VS_SO_GET_DAEMON
68 
69 
70 /*
71  *      IPVS Connection Flags
72  */
73 #define IP_VS_CONN_F_FWD_MASK	0x0007		/* mask for the fwd methods */
74 #define IP_VS_CONN_F_MASQ	0x0000		/* masquerading/NAT */
75 #define IP_VS_CONN_F_LOCALNODE	0x0001		/* local node */
76 #define IP_VS_CONN_F_TUNNEL	0x0002		/* tunneling */
77 #define IP_VS_CONN_F_DROUTE	0x0003		/* direct routing */
78 #define IP_VS_CONN_F_BYPASS	0x0004		/* cache bypass */
79 #define IP_VS_CONN_F_SYNC	0x0020		/* entry created by sync */
80 #define IP_VS_CONN_F_HASHED	0x0040		/* hashed entry */
81 #define IP_VS_CONN_F_NOOUTPUT	0x0080		/* no output packets */
82 #define IP_VS_CONN_F_INACTIVE	0x0100		/* not established */
83 #define IP_VS_CONN_F_OUT_SEQ	0x0200		/* must do output seq adjust */
84 #define IP_VS_CONN_F_IN_SEQ	0x0400		/* must do input seq adjust */
85 #define IP_VS_CONN_F_SEQ_MASK	0x0600		/* in/out sequence mask */
86 #define IP_VS_CONN_F_NO_CPORT	0x0800		/* no client port set yet */
87 #define IP_VS_CONN_F_TEMPLATE	0x1000		/* template, not connection */
88 
89 /* Move it to better place one day, for now keep it unique */
90 #define NFC_IPVS_PROPERTY	0x10000
91 
92 #define IP_VS_SCHEDNAME_MAXLEN	16
93 #define IP_VS_IFNAME_MAXLEN	16
94 
95 
96 /*
97  *	The struct ip_vs_service_user and struct ip_vs_dest_user are
98  *	used to set IPVS rules through setsockopt.
99  */
100 struct ip_vs_service_user {
101 	/* virtual service addresses */
102 	u_int16_t		protocol;
103 	u_int32_t		addr;		/* virtual ip address */
104 	u_int16_t		port;
105 	u_int32_t		fwmark;		/* firwall mark of service */
106 
107 	/* virtual service options */
108 	char			sched_name[IP_VS_SCHEDNAME_MAXLEN];
109 	unsigned		flags;		/* virtual service flags */
110 	unsigned		timeout;	/* persistent timeout in sec */
111 	u_int32_t		netmask;	/* persistent netmask */
112 };
113 
114 
115 struct ip_vs_dest_user {
116 	/* destination server address */
117 	u_int32_t		addr;
118 	u_int16_t		port;
119 
120 	/* real server options */
121 	unsigned		conn_flags;	/* connection flags */
122 	int			weight;		/* destination weight */
123 
124 	/* thresholds for active connections */
125 	u_int32_t		u_threshold;	/* upper threshold */
126 	u_int32_t		l_threshold;	/* lower threshold */
127 };
128 
129 
130 /*
131  *	IPVS statistics object (for user space)
132  */
133 struct ip_vs_stats_user
134 {
135 	__u32                   conns;          /* connections scheduled */
136 	__u32                   inpkts;         /* incoming packets */
137 	__u32                   outpkts;        /* outgoing packets */
138 	__u64                   inbytes;        /* incoming bytes */
139 	__u64                   outbytes;       /* outgoing bytes */
140 
141 	__u32			cps;		/* current connection rate */
142 	__u32			inpps;		/* current in packet rate */
143 	__u32			outpps;		/* current out packet rate */
144 	__u32			inbps;		/* current in byte rate */
145 	__u32			outbps;		/* current out byte rate */
146 };
147 
148 
149 /* The argument to IP_VS_SO_GET_INFO */
150 struct ip_vs_getinfo {
151 	/* version number */
152 	unsigned int		version;
153 
154 	/* size of connection hash table */
155 	unsigned int		size;
156 
157 	/* number of virtual services */
158 	unsigned int		num_services;
159 };
160 
161 
162 /* The argument to IP_VS_SO_GET_SERVICE */
163 struct ip_vs_service_entry {
164 	/* which service: user fills in these */
165 	u_int16_t		protocol;
166 	u_int32_t		addr;		/* virtual address */
167 	u_int16_t		port;
168 	u_int32_t		fwmark;		/* firwall mark of service */
169 
170 	/* service options */
171 	char			sched_name[IP_VS_SCHEDNAME_MAXLEN];
172 	unsigned		flags;          /* virtual service flags */
173 	unsigned		timeout;	/* persistent timeout */
174 	u_int32_t		netmask;	/* persistent netmask */
175 
176 	/* number of real servers */
177 	unsigned int		num_dests;
178 
179 	/* statistics */
180 	struct ip_vs_stats_user stats;
181 };
182 
183 
184 struct ip_vs_dest_entry {
185 	u_int32_t		addr;		/* destination address */
186 	u_int16_t		port;
187 	unsigned		conn_flags;	/* connection flags */
188 	int			weight;		/* destination weight */
189 
190 	u_int32_t		u_threshold;	/* upper threshold */
191 	u_int32_t		l_threshold;	/* lower threshold */
192 
193 	u_int32_t		activeconns;	/* active connections */
194 	u_int32_t		inactconns;	/* inactive connections */
195 	u_int32_t		persistconns;	/* persistent connections */
196 
197 	/* statistics */
198 	struct ip_vs_stats_user stats;
199 };
200 
201 
202 /* The argument to IP_VS_SO_GET_DESTS */
203 struct ip_vs_get_dests {
204 	/* which service: user fills in these */
205 	u_int16_t		protocol;
206 	u_int32_t		addr;		/* virtual address */
207 	u_int16_t		port;
208 	u_int32_t		fwmark;		/* firwall mark of service */
209 
210 	/* number of real servers */
211 	unsigned int		num_dests;
212 
213 	/* the real servers */
214 	struct ip_vs_dest_entry	entrytable[0];
215 };
216 
217 
218 /* The argument to IP_VS_SO_GET_SERVICES */
219 struct ip_vs_get_services {
220 	/* number of virtual services */
221 	unsigned int		num_services;
222 
223 	/* service table */
224 	struct ip_vs_service_entry entrytable[0];
225 };
226 
227 
228 /* The argument to IP_VS_SO_GET_TIMEOUT */
229 struct ip_vs_timeout_user {
230 	int			tcp_timeout;
231 	int			tcp_fin_timeout;
232 	int			udp_timeout;
233 };
234 
235 
236 /* The argument to IP_VS_SO_GET_DAEMON */
237 struct ip_vs_daemon_user {
238 	/* sync daemon state (master/backup) */
239 	int			state;
240 
241 	/* multicast interface name */
242 	char			mcast_ifn[IP_VS_IFNAME_MAXLEN];
243 
244 	/* SyncID we belong to */
245 	int			syncid;
246 };
247 
248 
249 #ifdef __KERNEL__
250 
251 #include <linux/config.h>
252 #include <linux/list.h>                 /* for struct list_head */
253 #include <linux/spinlock.h>             /* for struct rwlock_t */
254 #include <asm/atomic.h>                 /* for struct atomic_t */
255 #include <linux/compiler.h>
256 #include <linux/timer.h>
257 
258 #include <net/checksum.h>
259 
260 #ifdef CONFIG_IP_VS_DEBUG
261 #include <linux/net.h>
262 
263 extern int ip_vs_get_debug_level(void);
264 #define IP_VS_DBG(level, msg...)			\
265     do {						\
266 	    if (level <= ip_vs_get_debug_level())	\
267 		    printk(KERN_DEBUG "IPVS: " msg);	\
268     } while (0)
269 #define IP_VS_DBG_RL(msg...)				\
270     do {						\
271 	    if (net_ratelimit())			\
272 		    printk(KERN_DEBUG "IPVS: " msg);	\
273     } while (0)
274 #define IP_VS_DBG_PKT(level, pp, skb, ofs, msg)		\
275     do {						\
276 	    if (level <= ip_vs_get_debug_level())	\
277 		pp->debug_packet(pp, skb, ofs, msg);	\
278     } while (0)
279 #define IP_VS_DBG_RL_PKT(level, pp, skb, ofs, msg)	\
280     do {						\
281 	    if (level <= ip_vs_get_debug_level() &&	\
282 		net_ratelimit())			\
283 		pp->debug_packet(pp, skb, ofs, msg);	\
284     } while (0)
285 #else	/* NO DEBUGGING at ALL */
286 #define IP_VS_DBG(level, msg...)  do {} while (0)
287 #define IP_VS_DBG_RL(msg...)  do {} while (0)
288 #define IP_VS_DBG_PKT(level, pp, skb, ofs, msg)		do {} while (0)
289 #define IP_VS_DBG_RL_PKT(level, pp, skb, ofs, msg)	do {} while (0)
290 #endif
291 
292 #define IP_VS_BUG() BUG()
293 #define IP_VS_ERR(msg...) printk(KERN_ERR "IPVS: " msg)
294 #define IP_VS_INFO(msg...) printk(KERN_INFO "IPVS: " msg)
295 #define IP_VS_WARNING(msg...) \
296 	printk(KERN_WARNING "IPVS: " msg)
297 #define IP_VS_ERR_RL(msg...)				\
298     do {						\
299 	    if (net_ratelimit())			\
300 		    printk(KERN_ERR "IPVS: " msg);	\
301     } while (0)
302 
303 #ifdef CONFIG_IP_VS_DEBUG
304 #define EnterFunction(level)						\
305     do {								\
306 	    if (level <= ip_vs_get_debug_level())			\
307 		    printk(KERN_DEBUG "Enter: %s, %s line %i\n",	\
308 			   __FUNCTION__, __FILE__, __LINE__);		\
309     } while (0)
310 #define LeaveFunction(level)                                            \
311     do {                                                                \
312 	    if (level <= ip_vs_get_debug_level())                       \
313 			printk(KERN_DEBUG "Leave: %s, %s line %i\n",    \
314 			       __FUNCTION__, __FILE__, __LINE__);       \
315     } while (0)
316 #else
317 #define EnterFunction(level)   do {} while (0)
318 #define LeaveFunction(level)   do {} while (0)
319 #endif
320 
321 #define	IP_VS_WAIT_WHILE(expr)	while (expr) { cpu_relax(); }
322 
323 
324 /*
325  *      The port number of FTP service (in network order).
326  */
327 #define FTPPORT  __constant_htons(21)
328 #define FTPDATA  __constant_htons(20)
329 
330 /*
331  *      IPVS sysctl variables under the /proc/sys/net/ipv4/vs/
332  */
333 #define NET_IPV4_VS              21
334 
335 enum {
336 	NET_IPV4_VS_DEBUG_LEVEL=1,
337 	NET_IPV4_VS_AMEMTHRESH=2,
338 	NET_IPV4_VS_AMDROPRATE=3,
339 	NET_IPV4_VS_DROP_ENTRY=4,
340 	NET_IPV4_VS_DROP_PACKET=5,
341 	NET_IPV4_VS_SECURE_TCP=6,
342 	NET_IPV4_VS_TO_ES=7,
343 	NET_IPV4_VS_TO_SS=8,
344 	NET_IPV4_VS_TO_SR=9,
345 	NET_IPV4_VS_TO_FW=10,
346 	NET_IPV4_VS_TO_TW=11,
347 	NET_IPV4_VS_TO_CL=12,
348 	NET_IPV4_VS_TO_CW=13,
349 	NET_IPV4_VS_TO_LA=14,
350 	NET_IPV4_VS_TO_LI=15,
351 	NET_IPV4_VS_TO_SA=16,
352 	NET_IPV4_VS_TO_UDP=17,
353 	NET_IPV4_VS_TO_ICMP=18,
354 	NET_IPV4_VS_LBLC_EXPIRE=19,
355 	NET_IPV4_VS_LBLCR_EXPIRE=20,
356 	NET_IPV4_VS_CACHE_BYPASS=22,
357 	NET_IPV4_VS_EXPIRE_NODEST_CONN=23,
358 	NET_IPV4_VS_SYNC_THRESHOLD=24,
359 	NET_IPV4_VS_NAT_ICMP_SEND=25,
360 	NET_IPV4_VS_EXPIRE_QUIESCENT_TEMPLATE=26,
361 	NET_IPV4_VS_LAST
362 };
363 
364 /*
365  *      TCP State Values
366  */
367 enum {
368 	IP_VS_TCP_S_NONE = 0,
369 	IP_VS_TCP_S_ESTABLISHED,
370 	IP_VS_TCP_S_SYN_SENT,
371 	IP_VS_TCP_S_SYN_RECV,
372 	IP_VS_TCP_S_FIN_WAIT,
373 	IP_VS_TCP_S_TIME_WAIT,
374 	IP_VS_TCP_S_CLOSE,
375 	IP_VS_TCP_S_CLOSE_WAIT,
376 	IP_VS_TCP_S_LAST_ACK,
377 	IP_VS_TCP_S_LISTEN,
378 	IP_VS_TCP_S_SYNACK,
379 	IP_VS_TCP_S_LAST
380 };
381 
382 /*
383  *	UDP State Values
384  */
385 enum {
386 	IP_VS_UDP_S_NORMAL,
387 	IP_VS_UDP_S_LAST,
388 };
389 
390 /*
391  *	ICMP State Values
392  */
393 enum {
394 	IP_VS_ICMP_S_NORMAL,
395 	IP_VS_ICMP_S_LAST,
396 };
397 
398 /*
399  *	Delta sequence info structure
400  *	Each ip_vs_conn has 2 (output AND input seq. changes).
401  *      Only used in the VS/NAT.
402  */
403 struct ip_vs_seq {
404 	__u32			init_seq;	/* Add delta from this seq */
405 	__u32			delta;		/* Delta in sequence numbers */
406 	__u32			previous_delta;	/* Delta in sequence numbers
407 						   before last resized pkt */
408 };
409 
410 
411 /*
412  *	IPVS statistics object
413  */
414 struct ip_vs_stats
415 {
416 	__u32                   conns;          /* connections scheduled */
417 	__u32                   inpkts;         /* incoming packets */
418 	__u32                   outpkts;        /* outgoing packets */
419 	__u64                   inbytes;        /* incoming bytes */
420 	__u64                   outbytes;       /* outgoing bytes */
421 
422 	__u32			cps;		/* current connection rate */
423 	__u32			inpps;		/* current in packet rate */
424 	__u32			outpps;		/* current out packet rate */
425 	__u32			inbps;		/* current in byte rate */
426 	__u32			outbps;		/* current out byte rate */
427 
428 	spinlock_t              lock;           /* spin lock */
429 };
430 
431 struct dst_entry;
432 struct iphdr;
433 struct ip_vs_conn;
434 struct ip_vs_app;
435 struct sk_buff;
436 
437 struct ip_vs_protocol {
438 	struct ip_vs_protocol	*next;
439 	char			*name;
440 	__u16			protocol;
441 	int			dont_defrag;
442 	atomic_t		appcnt;		/* counter of proto app incs */
443 	int			*timeout_table;	/* protocol timeout table */
444 
445 	void (*init)(struct ip_vs_protocol *pp);
446 
447 	void (*exit)(struct ip_vs_protocol *pp);
448 
449 	int (*conn_schedule)(struct sk_buff *skb,
450 			     struct ip_vs_protocol *pp,
451 			     int *verdict, struct ip_vs_conn **cpp);
452 
453 	struct ip_vs_conn *
454 	(*conn_in_get)(const struct sk_buff *skb,
455 		       struct ip_vs_protocol *pp,
456 		       const struct iphdr *iph,
457 		       unsigned int proto_off,
458 		       int inverse);
459 
460 	struct ip_vs_conn *
461 	(*conn_out_get)(const struct sk_buff *skb,
462 			struct ip_vs_protocol *pp,
463 			const struct iphdr *iph,
464 			unsigned int proto_off,
465 			int inverse);
466 
467 	int (*snat_handler)(struct sk_buff **pskb,
468 			    struct ip_vs_protocol *pp, struct ip_vs_conn *cp);
469 
470 	int (*dnat_handler)(struct sk_buff **pskb,
471 			    struct ip_vs_protocol *pp, struct ip_vs_conn *cp);
472 
473 	int (*csum_check)(struct sk_buff *skb, struct ip_vs_protocol *pp);
474 
475 	const char *(*state_name)(int state);
476 
477 	int (*state_transition)(struct ip_vs_conn *cp, int direction,
478 				const struct sk_buff *skb,
479 				struct ip_vs_protocol *pp);
480 
481 	int (*register_app)(struct ip_vs_app *inc);
482 
483 	void (*unregister_app)(struct ip_vs_app *inc);
484 
485 	int (*app_conn_bind)(struct ip_vs_conn *cp);
486 
487 	void (*debug_packet)(struct ip_vs_protocol *pp,
488 			     const struct sk_buff *skb,
489 			     int offset,
490 			     const char *msg);
491 
492 	void (*timeout_change)(struct ip_vs_protocol *pp, int flags);
493 
494 	int (*set_state_timeout)(struct ip_vs_protocol *pp, char *sname, int to);
495 };
496 
497 extern struct ip_vs_protocol * ip_vs_proto_get(unsigned short proto);
498 
499 /*
500  *	IP_VS structure allocated for each dynamically scheduled connection
501  */
502 struct ip_vs_conn {
503 	struct list_head        c_list;         /* hashed list heads */
504 
505 	/* Protocol, addresses and port numbers */
506 	__u32                   caddr;          /* client address */
507 	__u32                   vaddr;          /* virtual address */
508 	__u32                   daddr;          /* destination address */
509 	__u16                   cport;
510 	__u16                   vport;
511 	__u16                   dport;
512 	__u16                   protocol;       /* Which protocol (TCP/UDP) */
513 
514 	/* counter and timer */
515 	atomic_t		refcnt;		/* reference count */
516 	struct timer_list	timer;		/* Expiration timer */
517 	volatile unsigned long	timeout;	/* timeout */
518 
519 	/* Flags and state transition */
520 	spinlock_t              lock;           /* lock for state transition */
521 	volatile __u16          flags;          /* status flags */
522 	volatile __u16          state;          /* state info */
523 
524 	/* Control members */
525 	struct ip_vs_conn       *control;       /* Master control connection */
526 	atomic_t                n_control;      /* Number of controlled ones */
527 	struct ip_vs_dest       *dest;          /* real server */
528 	atomic_t                in_pkts;        /* incoming packet counter */
529 
530 	/* packet transmitter for different forwarding methods.  If it
531 	   mangles the packet, it must return NF_DROP or better NF_STOLEN,
532 	   otherwise this must be changed to a sk_buff **.
533 	 */
534 	int (*packet_xmit)(struct sk_buff *skb, struct ip_vs_conn *cp,
535 			   struct ip_vs_protocol *pp);
536 
537 	/* Note: we can group the following members into a structure,
538 	   in order to save more space, and the following members are
539 	   only used in VS/NAT anyway */
540 	struct ip_vs_app        *app;           /* bound ip_vs_app object */
541 	void                    *app_data;      /* Application private data */
542 	struct ip_vs_seq        in_seq;         /* incoming seq. struct */
543 	struct ip_vs_seq        out_seq;        /* outgoing seq. struct */
544 };
545 
546 
547 /*
548  *	The information about the virtual service offered to the net
549  *	and the forwarding entries
550  */
551 struct ip_vs_service {
552 	struct list_head	s_list;   /* for normal service table */
553 	struct list_head	f_list;   /* for fwmark-based service table */
554 	atomic_t		refcnt;   /* reference counter */
555 	atomic_t		usecnt;   /* use counter */
556 
557 	__u16			protocol; /* which protocol (TCP/UDP) */
558 	__u32			addr;	  /* IP address for virtual service */
559 	__u16			port;	  /* port number for the service */
560 	__u32                   fwmark;   /* firewall mark of the service */
561 	unsigned		flags;	  /* service status flags */
562 	unsigned		timeout;  /* persistent timeout in ticks */
563 	__u32			netmask;  /* grouping granularity */
564 
565 	struct list_head	destinations;  /* real server d-linked list */
566 	__u32			num_dests;     /* number of servers */
567 	struct ip_vs_stats      stats;         /* statistics for the service */
568 	struct ip_vs_app	*inc;	  /* bind conns to this app inc */
569 
570 	/* for scheduling */
571 	struct ip_vs_scheduler	*scheduler;    /* bound scheduler object */
572 	rwlock_t		sched_lock;    /* lock sched_data */
573 	void			*sched_data;   /* scheduler application data */
574 };
575 
576 
577 /*
578  *	The real server destination forwarding entry
579  *	with ip address, port number, and so on.
580  */
581 struct ip_vs_dest {
582 	struct list_head	n_list;   /* for the dests in the service */
583 	struct list_head	d_list;   /* for table with all the dests */
584 
585 	__u32			addr;		/* IP address of the server */
586 	__u16			port;		/* port number of the server */
587 	volatile unsigned	flags;		/* dest status flags */
588 	atomic_t		conn_flags;	/* flags to copy to conn */
589 	atomic_t		weight;		/* server weight */
590 
591 	atomic_t		refcnt;		/* reference counter */
592 	struct ip_vs_stats      stats;          /* statistics */
593 
594 	/* connection counters and thresholds */
595 	atomic_t		activeconns;	/* active connections */
596 	atomic_t		inactconns;	/* inactive connections */
597 	atomic_t		persistconns;	/* persistent connections */
598 	__u32			u_threshold;	/* upper threshold */
599 	__u32			l_threshold;	/* lower threshold */
600 
601 	/* for destination cache */
602 	spinlock_t		dst_lock;	/* lock of dst_cache */
603 	struct dst_entry	*dst_cache;	/* destination cache entry */
604 	u32			dst_rtos;	/* RT_TOS(tos) for dst */
605 
606 	/* for virtual service */
607 	struct ip_vs_service	*svc;		/* service it belongs to */
608 	__u16			protocol;	/* which protocol (TCP/UDP) */
609 	__u32			vaddr;		/* virtual IP address */
610 	__u16			vport;		/* virtual port number */
611 	__u32			vfwmark;	/* firewall mark of service */
612 };
613 
614 
615 /*
616  *	The scheduler object
617  */
618 struct ip_vs_scheduler {
619 	struct list_head	n_list;		/* d-linked list head */
620 	char			*name;		/* scheduler name */
621 	atomic_t		refcnt;		/* reference counter */
622 	struct module		*module;	/* THIS_MODULE/NULL */
623 
624 	/* scheduler initializing service */
625 	int (*init_service)(struct ip_vs_service *svc);
626 	/* scheduling service finish */
627 	int (*done_service)(struct ip_vs_service *svc);
628 	/* scheduler updating service */
629 	int (*update_service)(struct ip_vs_service *svc);
630 
631 	/* selecting a server from the given service */
632 	struct ip_vs_dest* (*schedule)(struct ip_vs_service *svc,
633 				       const struct sk_buff *skb);
634 };
635 
636 
637 /*
638  *	The application module object (a.k.a. app incarnation)
639  */
640 struct ip_vs_app
641 {
642 	struct list_head	a_list;		/* member in app list */
643 	int			type;		/* IP_VS_APP_TYPE_xxx */
644 	char			*name;		/* application module name */
645 	__u16			protocol;
646 	struct module		*module;	/* THIS_MODULE/NULL */
647 	struct list_head	incs_list;	/* list of incarnations */
648 
649 	/* members for application incarnations */
650 	struct list_head	p_list;		/* member in proto app list */
651 	struct ip_vs_app	*app;		/* its real application */
652 	__u16			port;		/* port number in net order */
653 	atomic_t		usecnt;		/* usage counter */
654 
655 	/* output hook: return false if can't linearize. diff set for TCP.  */
656 	int (*pkt_out)(struct ip_vs_app *, struct ip_vs_conn *,
657 		       struct sk_buff **, int *diff);
658 
659 	/* input hook: return false if can't linearize. diff set for TCP. */
660 	int (*pkt_in)(struct ip_vs_app *, struct ip_vs_conn *,
661 		      struct sk_buff **, int *diff);
662 
663 	/* ip_vs_app initializer */
664 	int (*init_conn)(struct ip_vs_app *, struct ip_vs_conn *);
665 
666 	/* ip_vs_app finish */
667 	int (*done_conn)(struct ip_vs_app *, struct ip_vs_conn *);
668 
669 
670 	/* not used now */
671 	int (*bind_conn)(struct ip_vs_app *, struct ip_vs_conn *,
672 			 struct ip_vs_protocol *);
673 
674 	void (*unbind_conn)(struct ip_vs_app *, struct ip_vs_conn *);
675 
676 	int *			timeout_table;
677 	int *			timeouts;
678 	int			timeouts_size;
679 
680 	int (*conn_schedule)(struct sk_buff *skb, struct ip_vs_app *app,
681 			     int *verdict, struct ip_vs_conn **cpp);
682 
683 	struct ip_vs_conn *
684 	(*conn_in_get)(const struct sk_buff *skb, struct ip_vs_app *app,
685 		       const struct iphdr *iph, unsigned int proto_off,
686 		       int inverse);
687 
688 	struct ip_vs_conn *
689 	(*conn_out_get)(const struct sk_buff *skb, struct ip_vs_app *app,
690 			const struct iphdr *iph, unsigned int proto_off,
691 			int inverse);
692 
693 	int (*state_transition)(struct ip_vs_conn *cp, int direction,
694 				const struct sk_buff *skb,
695 				struct ip_vs_app *app);
696 
697 	void (*timeout_change)(struct ip_vs_app *app, int flags);
698 };
699 
700 
701 /*
702  *      IPVS core functions
703  *      (from ip_vs_core.c)
704  */
705 extern const char *ip_vs_proto_name(unsigned proto);
706 extern void ip_vs_init_hash_table(struct list_head *table, int rows);
707 #define IP_VS_INIT_HASH_TABLE(t) ip_vs_init_hash_table(t, sizeof(t)/sizeof(t[0]))
708 
709 #define IP_VS_APP_TYPE_UNSPEC	0
710 #define IP_VS_APP_TYPE_FTP	1
711 
712 /*
713  *     ip_vs_conn handling functions
714  *     (from ip_vs_conn.c)
715  */
716 
717 /*
718  *     IPVS connection entry hash table
719  */
720 #ifndef CONFIG_IP_VS_TAB_BITS
721 #define CONFIG_IP_VS_TAB_BITS   12
722 #endif
723 /* make sure that IP_VS_CONN_TAB_BITS is located in [8, 20] */
724 #if CONFIG_IP_VS_TAB_BITS < 8
725 #define IP_VS_CONN_TAB_BITS	8
726 #endif
727 #if CONFIG_IP_VS_TAB_BITS > 20
728 #define IP_VS_CONN_TAB_BITS	20
729 #endif
730 #if 8 <= CONFIG_IP_VS_TAB_BITS && CONFIG_IP_VS_TAB_BITS <= 20
731 #define IP_VS_CONN_TAB_BITS	CONFIG_IP_VS_TAB_BITS
732 #endif
733 #define IP_VS_CONN_TAB_SIZE     (1 << IP_VS_CONN_TAB_BITS)
734 #define IP_VS_CONN_TAB_MASK     (IP_VS_CONN_TAB_SIZE - 1)
735 
736 enum {
737 	IP_VS_DIR_INPUT = 0,
738 	IP_VS_DIR_OUTPUT,
739 	IP_VS_DIR_INPUT_ONLY,
740 	IP_VS_DIR_LAST,
741 };
742 
743 extern struct ip_vs_conn *ip_vs_conn_in_get
744 (int protocol, __u32 s_addr, __u16 s_port, __u32 d_addr, __u16 d_port);
745 extern struct ip_vs_conn *ip_vs_ct_in_get
746 (int protocol, __u32 s_addr, __u16 s_port, __u32 d_addr, __u16 d_port);
747 extern struct ip_vs_conn *ip_vs_conn_out_get
748 (int protocol, __u32 s_addr, __u16 s_port, __u32 d_addr, __u16 d_port);
749 
750 /* put back the conn without restarting its timer */
751 static inline void __ip_vs_conn_put(struct ip_vs_conn *cp)
752 {
753 	atomic_dec(&cp->refcnt);
754 }
755 extern void ip_vs_conn_put(struct ip_vs_conn *cp);
756 extern void ip_vs_conn_fill_cport(struct ip_vs_conn *cp, __u16 cport);
757 
758 extern struct ip_vs_conn *
759 ip_vs_conn_new(int proto, __u32 caddr, __u16 cport, __u32 vaddr, __u16 vport,
760 	       __u32 daddr, __u16 dport, unsigned flags,
761 	       struct ip_vs_dest *dest);
762 extern void ip_vs_conn_expire_now(struct ip_vs_conn *cp);
763 
764 extern const char * ip_vs_state_name(__u16 proto, int state);
765 
766 extern void ip_vs_tcp_conn_listen(struct ip_vs_conn *cp);
767 extern int ip_vs_check_template(struct ip_vs_conn *ct);
768 extern void ip_vs_secure_tcp_set(int on);
769 extern void ip_vs_random_dropentry(void);
770 extern int ip_vs_conn_init(void);
771 extern void ip_vs_conn_cleanup(void);
772 
773 static inline void ip_vs_control_del(struct ip_vs_conn *cp)
774 {
775 	struct ip_vs_conn *ctl_cp = cp->control;
776 	if (!ctl_cp) {
777 		IP_VS_ERR("request control DEL for uncontrolled: "
778 			  "%d.%d.%d.%d:%d to %d.%d.%d.%d:%d\n",
779 			  NIPQUAD(cp->caddr),ntohs(cp->cport),
780 			  NIPQUAD(cp->vaddr),ntohs(cp->vport));
781 		return;
782 	}
783 
784 	IP_VS_DBG(7, "DELeting control for: "
785 		  "cp.dst=%d.%d.%d.%d:%d ctl_cp.dst=%d.%d.%d.%d:%d\n",
786 		  NIPQUAD(cp->caddr),ntohs(cp->cport),
787 		  NIPQUAD(ctl_cp->caddr),ntohs(ctl_cp->cport));
788 
789 	cp->control = NULL;
790 	if (atomic_read(&ctl_cp->n_control) == 0) {
791 		IP_VS_ERR("BUG control DEL with n=0 : "
792 			  "%d.%d.%d.%d:%d to %d.%d.%d.%d:%d\n",
793 			  NIPQUAD(cp->caddr),ntohs(cp->cport),
794 			  NIPQUAD(cp->vaddr),ntohs(cp->vport));
795 		return;
796 	}
797 	atomic_dec(&ctl_cp->n_control);
798 }
799 
800 static inline void
801 ip_vs_control_add(struct ip_vs_conn *cp, struct ip_vs_conn *ctl_cp)
802 {
803 	if (cp->control) {
804 		IP_VS_ERR("request control ADD for already controlled: "
805 			  "%d.%d.%d.%d:%d to %d.%d.%d.%d:%d\n",
806 			  NIPQUAD(cp->caddr),ntohs(cp->cport),
807 			  NIPQUAD(cp->vaddr),ntohs(cp->vport));
808 		ip_vs_control_del(cp);
809 	}
810 
811 	IP_VS_DBG(7, "ADDing control for: "
812 		  "cp.dst=%d.%d.%d.%d:%d ctl_cp.dst=%d.%d.%d.%d:%d\n",
813 		  NIPQUAD(cp->caddr),ntohs(cp->cport),
814 		  NIPQUAD(ctl_cp->caddr),ntohs(ctl_cp->cport));
815 
816 	cp->control = ctl_cp;
817 	atomic_inc(&ctl_cp->n_control);
818 }
819 
820 
821 /*
822  *      IPVS application functions
823  *      (from ip_vs_app.c)
824  */
825 #define IP_VS_APP_MAX_PORTS  8
826 extern int register_ip_vs_app(struct ip_vs_app *app);
827 extern void unregister_ip_vs_app(struct ip_vs_app *app);
828 extern int ip_vs_bind_app(struct ip_vs_conn *cp, struct ip_vs_protocol *pp);
829 extern void ip_vs_unbind_app(struct ip_vs_conn *cp);
830 extern int
831 register_ip_vs_app_inc(struct ip_vs_app *app, __u16 proto, __u16 port);
832 extern int ip_vs_app_inc_get(struct ip_vs_app *inc);
833 extern void ip_vs_app_inc_put(struct ip_vs_app *inc);
834 
835 extern int ip_vs_app_pkt_out(struct ip_vs_conn *, struct sk_buff **pskb);
836 extern int ip_vs_app_pkt_in(struct ip_vs_conn *, struct sk_buff **pskb);
837 extern int ip_vs_skb_replace(struct sk_buff *skb, gfp_t pri,
838 			     char *o_buf, int o_len, char *n_buf, int n_len);
839 extern int ip_vs_app_init(void);
840 extern void ip_vs_app_cleanup(void);
841 
842 
843 /*
844  *	IPVS protocol functions (from ip_vs_proto.c)
845  */
846 extern int ip_vs_protocol_init(void);
847 extern void ip_vs_protocol_cleanup(void);
848 extern void ip_vs_protocol_timeout_change(int flags);
849 extern int *ip_vs_create_timeout_table(int *table, int size);
850 extern int
851 ip_vs_set_state_timeout(int *table, int num, char **names, char *name, int to);
852 extern void
853 ip_vs_tcpudp_debug_packet(struct ip_vs_protocol *pp, const struct sk_buff *skb,
854 			  int offset, const char *msg);
855 
856 extern struct ip_vs_protocol ip_vs_protocol_tcp;
857 extern struct ip_vs_protocol ip_vs_protocol_udp;
858 extern struct ip_vs_protocol ip_vs_protocol_icmp;
859 extern struct ip_vs_protocol ip_vs_protocol_esp;
860 extern struct ip_vs_protocol ip_vs_protocol_ah;
861 
862 
863 /*
864  *      Registering/unregistering scheduler functions
865  *      (from ip_vs_sched.c)
866  */
867 extern int register_ip_vs_scheduler(struct ip_vs_scheduler *scheduler);
868 extern int unregister_ip_vs_scheduler(struct ip_vs_scheduler *scheduler);
869 extern int ip_vs_bind_scheduler(struct ip_vs_service *svc,
870 				struct ip_vs_scheduler *scheduler);
871 extern int ip_vs_unbind_scheduler(struct ip_vs_service *svc);
872 extern struct ip_vs_scheduler *ip_vs_scheduler_get(const char *sched_name);
873 extern void ip_vs_scheduler_put(struct ip_vs_scheduler *scheduler);
874 extern struct ip_vs_conn *
875 ip_vs_schedule(struct ip_vs_service *svc, const struct sk_buff *skb);
876 extern int ip_vs_leave(struct ip_vs_service *svc, struct sk_buff *skb,
877 			struct ip_vs_protocol *pp);
878 
879 
880 /*
881  *      IPVS control data and functions (from ip_vs_ctl.c)
882  */
883 extern int sysctl_ip_vs_cache_bypass;
884 extern int sysctl_ip_vs_expire_nodest_conn;
885 extern int sysctl_ip_vs_expire_quiescent_template;
886 extern int sysctl_ip_vs_sync_threshold[2];
887 extern int sysctl_ip_vs_nat_icmp_send;
888 extern struct ip_vs_stats ip_vs_stats;
889 
890 extern struct ip_vs_service *
891 ip_vs_service_get(__u32 fwmark, __u16 protocol, __u32 vaddr, __u16 vport);
892 
893 static inline void ip_vs_service_put(struct ip_vs_service *svc)
894 {
895 	atomic_dec(&svc->usecnt);
896 }
897 
898 extern struct ip_vs_dest *
899 ip_vs_lookup_real_service(__u16 protocol, __u32 daddr, __u16 dport);
900 extern int ip_vs_use_count_inc(void);
901 extern void ip_vs_use_count_dec(void);
902 extern int ip_vs_control_init(void);
903 extern void ip_vs_control_cleanup(void);
904 
905 
906 /*
907  *      IPVS sync daemon data and function prototypes
908  *      (from ip_vs_sync.c)
909  */
910 extern volatile int ip_vs_sync_state;
911 extern volatile int ip_vs_master_syncid;
912 extern volatile int ip_vs_backup_syncid;
913 extern char ip_vs_master_mcast_ifn[IP_VS_IFNAME_MAXLEN];
914 extern char ip_vs_backup_mcast_ifn[IP_VS_IFNAME_MAXLEN];
915 extern int start_sync_thread(int state, char *mcast_ifn, __u8 syncid);
916 extern int stop_sync_thread(int state);
917 extern void ip_vs_sync_conn(struct ip_vs_conn *cp);
918 
919 
920 /*
921  *      IPVS rate estimator prototypes (from ip_vs_est.c)
922  */
923 extern int ip_vs_new_estimator(struct ip_vs_stats *stats);
924 extern void ip_vs_kill_estimator(struct ip_vs_stats *stats);
925 extern void ip_vs_zero_estimator(struct ip_vs_stats *stats);
926 
927 /*
928  *	Various IPVS packet transmitters (from ip_vs_xmit.c)
929  */
930 extern int ip_vs_null_xmit
931 (struct sk_buff *skb, struct ip_vs_conn *cp, struct ip_vs_protocol *pp);
932 extern int ip_vs_bypass_xmit
933 (struct sk_buff *skb, struct ip_vs_conn *cp, struct ip_vs_protocol *pp);
934 extern int ip_vs_nat_xmit
935 (struct sk_buff *skb, struct ip_vs_conn *cp, struct ip_vs_protocol *pp);
936 extern int ip_vs_tunnel_xmit
937 (struct sk_buff *skb, struct ip_vs_conn *cp, struct ip_vs_protocol *pp);
938 extern int ip_vs_dr_xmit
939 (struct sk_buff *skb, struct ip_vs_conn *cp, struct ip_vs_protocol *pp);
940 extern int ip_vs_icmp_xmit
941 (struct sk_buff *skb, struct ip_vs_conn *cp, struct ip_vs_protocol *pp, int offset);
942 extern void ip_vs_dst_reset(struct ip_vs_dest *dest);
943 
944 
945 /*
946  *	This is a simple mechanism to ignore packets when
947  *	we are loaded. Just set ip_vs_drop_rate to 'n' and
948  *	we start to drop 1/rate of the packets
949  */
950 extern int ip_vs_drop_rate;
951 extern int ip_vs_drop_counter;
952 
953 static __inline__ int ip_vs_todrop(void)
954 {
955 	if (!ip_vs_drop_rate) return 0;
956 	if (--ip_vs_drop_counter > 0) return 0;
957 	ip_vs_drop_counter = ip_vs_drop_rate;
958 	return 1;
959 }
960 
961 /*
962  *      ip_vs_fwd_tag returns the forwarding tag of the connection
963  */
964 #define IP_VS_FWD_METHOD(cp)  (cp->flags & IP_VS_CONN_F_FWD_MASK)
965 
966 static inline char ip_vs_fwd_tag(struct ip_vs_conn *cp)
967 {
968 	char fwd;
969 
970 	switch (IP_VS_FWD_METHOD(cp)) {
971 	case IP_VS_CONN_F_MASQ:
972 		fwd = 'M'; break;
973 	case IP_VS_CONN_F_LOCALNODE:
974 		fwd = 'L'; break;
975 	case IP_VS_CONN_F_TUNNEL:
976 		fwd = 'T'; break;
977 	case IP_VS_CONN_F_DROUTE:
978 		fwd = 'R'; break;
979 	case IP_VS_CONN_F_BYPASS:
980 		fwd = 'B'; break;
981 	default:
982 		fwd = '?'; break;
983 	}
984 	return fwd;
985 }
986 
987 extern int ip_vs_make_skb_writable(struct sk_buff **pskb, int len);
988 extern void ip_vs_nat_icmp(struct sk_buff *skb, struct ip_vs_protocol *pp,
989 		struct ip_vs_conn *cp, int dir);
990 
991 extern u16 ip_vs_checksum_complete(struct sk_buff *skb, int offset);
992 
993 static inline u16 ip_vs_check_diff(u32 old, u32 new, u16 oldsum)
994 {
995 	u32 diff[2] = { old, new };
996 
997 	return csum_fold(csum_partial((char *) diff, sizeof(diff),
998 				      oldsum ^ 0xFFFF));
999 }
1000 
1001 #endif /* __KERNEL__ */
1002 
1003 #endif	/* _IP_VS_H */
1004