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1 /*
2  * IPVS         An implementation of the IP virtual server support for the
3  *              LINUX operating system.  IPVS is now implemented as a module
4  *              over the NetFilter framework. IPVS can be used to build a
5  *              high-performance and highly available server based on a
6  *              cluster of servers.
7  *
8  * Version 1,   is capable of handling both version 0 and 1 messages.
9  *              Version 0 is the plain old format.
10  *              Note Version 0 receivers will just drop Ver 1 messages.
11  *              Version 1 is capable of handle IPv6, Persistence data,
12  *              time-outs, and firewall marks.
13  *              In ver.1 "ip_vs_sync_conn_options" will be sent in netw. order.
14  *              Ver. 0 can be turned on by sysctl -w net.ipv4.vs.sync_version=0
15  *
16  * Definitions  Message: is a complete datagram
17  *              Sync_conn: is a part of a Message
18  *              Param Data is an option to a Sync_conn.
19  *
20  * Authors:     Wensong Zhang <wensong@linuxvirtualserver.org>
21  *
22  * ip_vs_sync:  sync connection info from master load balancer to backups
23  *              through multicast
24  *
25  * Changes:
26  *	Alexandre Cassen	:	Added master & backup support at a time.
27  *	Alexandre Cassen	:	Added SyncID support for incoming sync
28  *					messages filtering.
29  *	Justin Ossevoort	:	Fix endian problem on sync message size.
30  *	Hans Schillstrom	:	Added Version 1: i.e. IPv6,
31  *					Persistence support, fwmark and time-out.
32  */
33 
34 #define KMSG_COMPONENT "IPVS"
35 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
36 
37 #include <linux/module.h>
38 #include <linux/slab.h>
39 #include <linux/inetdevice.h>
40 #include <linux/net.h>
41 #include <linux/completion.h>
42 #include <linux/delay.h>
43 #include <linux/skbuff.h>
44 #include <linux/in.h>
45 #include <linux/igmp.h>                 /* for ip_mc_join_group */
46 #include <linux/udp.h>
47 #include <linux/err.h>
48 #include <linux/kthread.h>
49 #include <linux/wait.h>
50 #include <linux/kernel.h>
51 
52 #include <asm/unaligned.h>		/* Used for ntoh_seq and hton_seq */
53 
54 #include <net/ip.h>
55 #include <net/sock.h>
56 
57 #include <net/ip_vs.h>
58 
59 #define IP_VS_SYNC_GROUP 0xe0000051    /* multicast addr - 224.0.0.81 */
60 #define IP_VS_SYNC_PORT  8848          /* multicast port */
61 
62 #define SYNC_PROTO_VER  1		/* Protocol version in header */
63 
64 static struct lock_class_key __ipvs_sync_key;
65 /*
66  *	IPVS sync connection entry
67  *	Version 0, i.e. original version.
68  */
69 struct ip_vs_sync_conn_v0 {
70 	__u8			reserved;
71 
72 	/* Protocol, addresses and port numbers */
73 	__u8			protocol;       /* Which protocol (TCP/UDP) */
74 	__be16			cport;
75 	__be16                  vport;
76 	__be16                  dport;
77 	__be32                  caddr;          /* client address */
78 	__be32                  vaddr;          /* virtual address */
79 	__be32                  daddr;          /* destination address */
80 
81 	/* Flags and state transition */
82 	__be16                  flags;          /* status flags */
83 	__be16                  state;          /* state info */
84 
85 	/* The sequence options start here */
86 };
87 
88 struct ip_vs_sync_conn_options {
89 	struct ip_vs_seq        in_seq;         /* incoming seq. struct */
90 	struct ip_vs_seq        out_seq;        /* outgoing seq. struct */
91 };
92 
93 /*
94      Sync Connection format (sync_conn)
95 
96        0                   1                   2                   3
97        0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
98       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
99       |    Type       |    Protocol   | Ver.  |        Size           |
100       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
101       |                             Flags                             |
102       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
103       |            State              |         cport                 |
104       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
105       |            vport              |         dport                 |
106       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
107       |                             fwmark                            |
108       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
109       |                             timeout  (in sec.)                |
110       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
111       |                              ...                              |
112       |                        IP-Addresses  (v4 or v6)               |
113       |                              ...                              |
114       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
115   Optional Parameters.
116       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
117       | Param. Type    | Param. Length |   Param. data                |
118       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+                               |
119       |                              ...                              |
120       |                               +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
121       |                               | Param Type    | Param. Length |
122       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
123       |                           Param  data                         |
124       |         Last Param data should be padded for 32 bit alignment |
125       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
126 */
127 
128 /*
129  *  Type 0, IPv4 sync connection format
130  */
131 struct ip_vs_sync_v4 {
132 	__u8			type;
133 	__u8			protocol;	/* Which protocol (TCP/UDP) */
134 	__be16			ver_size;	/* Version msb 4 bits */
135 	/* Flags and state transition */
136 	__be32			flags;		/* status flags */
137 	__be16			state;		/* state info 	*/
138 	/* Protocol, addresses and port numbers */
139 	__be16			cport;
140 	__be16			vport;
141 	__be16			dport;
142 	__be32			fwmark;		/* Firewall mark from skb */
143 	__be32			timeout;	/* cp timeout */
144 	__be32			caddr;		/* client address */
145 	__be32			vaddr;		/* virtual address */
146 	__be32			daddr;		/* destination address */
147 	/* The sequence options start here */
148 	/* PE data padded to 32bit alignment after seq. options */
149 };
150 /*
151  * Type 2 messages IPv6
152  */
153 struct ip_vs_sync_v6 {
154 	__u8			type;
155 	__u8			protocol;	/* Which protocol (TCP/UDP) */
156 	__be16			ver_size;	/* Version msb 4 bits */
157 	/* Flags and state transition */
158 	__be32			flags;		/* status flags */
159 	__be16			state;		/* state info 	*/
160 	/* Protocol, addresses and port numbers */
161 	__be16			cport;
162 	__be16			vport;
163 	__be16			dport;
164 	__be32			fwmark;		/* Firewall mark from skb */
165 	__be32			timeout;	/* cp timeout */
166 	struct in6_addr		caddr;		/* client address */
167 	struct in6_addr		vaddr;		/* virtual address */
168 	struct in6_addr		daddr;		/* destination address */
169 	/* The sequence options start here */
170 	/* PE data padded to 32bit alignment after seq. options */
171 };
172 
173 union ip_vs_sync_conn {
174 	struct ip_vs_sync_v4	v4;
175 	struct ip_vs_sync_v6	v6;
176 };
177 
178 /* Bits in Type field in above */
179 #define STYPE_INET6		0
180 #define STYPE_F_INET6		(1 << STYPE_INET6)
181 
182 #define SVER_SHIFT		12		/* Shift to get version */
183 #define SVER_MASK		0x0fff		/* Mask to strip version */
184 
185 #define IPVS_OPT_SEQ_DATA	1
186 #define IPVS_OPT_PE_DATA	2
187 #define IPVS_OPT_PE_NAME	3
188 #define IPVS_OPT_PARAM		7
189 
190 #define IPVS_OPT_F_SEQ_DATA	(1 << (IPVS_OPT_SEQ_DATA-1))
191 #define IPVS_OPT_F_PE_DATA	(1 << (IPVS_OPT_PE_DATA-1))
192 #define IPVS_OPT_F_PE_NAME	(1 << (IPVS_OPT_PE_NAME-1))
193 #define IPVS_OPT_F_PARAM	(1 << (IPVS_OPT_PARAM-1))
194 
195 struct ip_vs_sync_thread_data {
196 	struct net *net;
197 	struct socket *sock;
198 	char *buf;
199 	int id;
200 };
201 
202 /* Version 0 definition of packet sizes */
203 #define SIMPLE_CONN_SIZE  (sizeof(struct ip_vs_sync_conn_v0))
204 #define FULL_CONN_SIZE  \
205 (sizeof(struct ip_vs_sync_conn_v0) + sizeof(struct ip_vs_sync_conn_options))
206 
207 
208 /*
209   The master mulitcasts messages (Datagrams) to the backup load balancers
210   in the following format.
211 
212  Version 1:
213   Note, first byte should be Zero, so ver 0 receivers will drop the packet.
214 
215        0                   1                   2                   3
216        0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
217       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
218       |      0        |    SyncID     |            Size               |
219       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
220       |  Count Conns  |    Version    |    Reserved, set to Zero      |
221       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
222       |                                                               |
223       |                    IPVS Sync Connection (1)                   |
224       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
225       |                            .                                  |
226       ~                            .                                  ~
227       |                            .                                  |
228       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
229       |                                                               |
230       |                    IPVS Sync Connection (n)                   |
231       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
232 
233  Version 0 Header
234        0                   1                   2                   3
235        0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
236       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
237       |  Count Conns  |    SyncID     |            Size               |
238       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
239       |                    IPVS Sync Connection (1)                   |
240 */
241 
242 #define SYNC_MESG_HEADER_LEN	4
243 #define MAX_CONNS_PER_SYNCBUFF	255 /* nr_conns in ip_vs_sync_mesg is 8 bit */
244 
245 /* Version 0 header */
246 struct ip_vs_sync_mesg_v0 {
247 	__u8                    nr_conns;
248 	__u8                    syncid;
249 	__be16                  size;
250 
251 	/* ip_vs_sync_conn entries start here */
252 };
253 
254 /* Version 1 header */
255 struct ip_vs_sync_mesg {
256 	__u8			reserved;	/* must be zero */
257 	__u8			syncid;
258 	__be16			size;
259 	__u8			nr_conns;
260 	__s8			version;	/* SYNC_PROTO_VER  */
261 	__u16			spare;
262 	/* ip_vs_sync_conn entries start here */
263 };
264 
265 struct ip_vs_sync_buff {
266 	struct list_head        list;
267 	unsigned long           firstuse;
268 
269 	/* pointers for the message data */
270 	struct ip_vs_sync_mesg  *mesg;
271 	unsigned char           *head;
272 	unsigned char           *end;
273 };
274 
275 /*
276  * Copy of struct ip_vs_seq
277  * From unaligned network order to aligned host order
278  */
ntoh_seq(struct ip_vs_seq * no,struct ip_vs_seq * ho)279 static void ntoh_seq(struct ip_vs_seq *no, struct ip_vs_seq *ho)
280 {
281 	ho->init_seq       = get_unaligned_be32(&no->init_seq);
282 	ho->delta          = get_unaligned_be32(&no->delta);
283 	ho->previous_delta = get_unaligned_be32(&no->previous_delta);
284 }
285 
286 /*
287  * Copy of struct ip_vs_seq
288  * From Aligned host order to unaligned network order
289  */
hton_seq(struct ip_vs_seq * ho,struct ip_vs_seq * no)290 static void hton_seq(struct ip_vs_seq *ho, struct ip_vs_seq *no)
291 {
292 	put_unaligned_be32(ho->init_seq, &no->init_seq);
293 	put_unaligned_be32(ho->delta, &no->delta);
294 	put_unaligned_be32(ho->previous_delta, &no->previous_delta);
295 }
296 
297 static inline struct ip_vs_sync_buff *
sb_dequeue(struct netns_ipvs * ipvs,struct ipvs_master_sync_state * ms)298 sb_dequeue(struct netns_ipvs *ipvs, struct ipvs_master_sync_state *ms)
299 {
300 	struct ip_vs_sync_buff *sb;
301 
302 	spin_lock_bh(&ipvs->sync_lock);
303 	if (list_empty(&ms->sync_queue)) {
304 		sb = NULL;
305 		__set_current_state(TASK_INTERRUPTIBLE);
306 	} else {
307 		sb = list_entry(ms->sync_queue.next, struct ip_vs_sync_buff,
308 				list);
309 		list_del(&sb->list);
310 		ms->sync_queue_len--;
311 		if (!ms->sync_queue_len)
312 			ms->sync_queue_delay = 0;
313 	}
314 	spin_unlock_bh(&ipvs->sync_lock);
315 
316 	return sb;
317 }
318 
319 /*
320  * Create a new sync buffer for Version 1 proto.
321  */
322 static inline struct ip_vs_sync_buff *
ip_vs_sync_buff_create(struct netns_ipvs * ipvs)323 ip_vs_sync_buff_create(struct netns_ipvs *ipvs)
324 {
325 	struct ip_vs_sync_buff *sb;
326 
327 	if (!(sb=kmalloc(sizeof(struct ip_vs_sync_buff), GFP_ATOMIC)))
328 		return NULL;
329 
330 	sb->mesg = kmalloc(ipvs->send_mesg_maxlen, GFP_ATOMIC);
331 	if (!sb->mesg) {
332 		kfree(sb);
333 		return NULL;
334 	}
335 	sb->mesg->reserved = 0;  /* old nr_conns i.e. must be zero now */
336 	sb->mesg->version = SYNC_PROTO_VER;
337 	sb->mesg->syncid = ipvs->master_syncid;
338 	sb->mesg->size = htons(sizeof(struct ip_vs_sync_mesg));
339 	sb->mesg->nr_conns = 0;
340 	sb->mesg->spare = 0;
341 	sb->head = (unsigned char *)sb->mesg + sizeof(struct ip_vs_sync_mesg);
342 	sb->end = (unsigned char *)sb->mesg + ipvs->send_mesg_maxlen;
343 
344 	sb->firstuse = jiffies;
345 	return sb;
346 }
347 
ip_vs_sync_buff_release(struct ip_vs_sync_buff * sb)348 static inline void ip_vs_sync_buff_release(struct ip_vs_sync_buff *sb)
349 {
350 	kfree(sb->mesg);
351 	kfree(sb);
352 }
353 
sb_queue_tail(struct netns_ipvs * ipvs,struct ipvs_master_sync_state * ms)354 static inline void sb_queue_tail(struct netns_ipvs *ipvs,
355 				 struct ipvs_master_sync_state *ms)
356 {
357 	struct ip_vs_sync_buff *sb = ms->sync_buff;
358 
359 	spin_lock(&ipvs->sync_lock);
360 	if (ipvs->sync_state & IP_VS_STATE_MASTER &&
361 	    ms->sync_queue_len < sysctl_sync_qlen_max(ipvs)) {
362 		if (!ms->sync_queue_len)
363 			schedule_delayed_work(&ms->master_wakeup_work,
364 					      max(IPVS_SYNC_SEND_DELAY, 1));
365 		ms->sync_queue_len++;
366 		list_add_tail(&sb->list, &ms->sync_queue);
367 		if ((++ms->sync_queue_delay) == IPVS_SYNC_WAKEUP_RATE)
368 			wake_up_process(ms->master_thread);
369 	} else
370 		ip_vs_sync_buff_release(sb);
371 	spin_unlock(&ipvs->sync_lock);
372 }
373 
374 /*
375  *	Get the current sync buffer if it has been created for more
376  *	than the specified time or the specified time is zero.
377  */
378 static inline struct ip_vs_sync_buff *
get_curr_sync_buff(struct netns_ipvs * ipvs,struct ipvs_master_sync_state * ms,unsigned long time)379 get_curr_sync_buff(struct netns_ipvs *ipvs, struct ipvs_master_sync_state *ms,
380 		   unsigned long time)
381 {
382 	struct ip_vs_sync_buff *sb;
383 
384 	spin_lock_bh(&ipvs->sync_buff_lock);
385 	sb = ms->sync_buff;
386 	if (sb && time_after_eq(jiffies - sb->firstuse, time)) {
387 		ms->sync_buff = NULL;
388 		__set_current_state(TASK_RUNNING);
389 	} else
390 		sb = NULL;
391 	spin_unlock_bh(&ipvs->sync_buff_lock);
392 	return sb;
393 }
394 
395 static inline int
select_master_thread_id(struct netns_ipvs * ipvs,struct ip_vs_conn * cp)396 select_master_thread_id(struct netns_ipvs *ipvs, struct ip_vs_conn *cp)
397 {
398 	return ((long) cp >> (1 + ilog2(sizeof(*cp)))) & ipvs->threads_mask;
399 }
400 
401 /*
402  * Create a new sync buffer for Version 0 proto.
403  */
404 static inline struct ip_vs_sync_buff *
ip_vs_sync_buff_create_v0(struct netns_ipvs * ipvs)405 ip_vs_sync_buff_create_v0(struct netns_ipvs *ipvs)
406 {
407 	struct ip_vs_sync_buff *sb;
408 	struct ip_vs_sync_mesg_v0 *mesg;
409 
410 	if (!(sb=kmalloc(sizeof(struct ip_vs_sync_buff), GFP_ATOMIC)))
411 		return NULL;
412 
413 	sb->mesg = kmalloc(ipvs->send_mesg_maxlen, GFP_ATOMIC);
414 	if (!sb->mesg) {
415 		kfree(sb);
416 		return NULL;
417 	}
418 	mesg = (struct ip_vs_sync_mesg_v0 *)sb->mesg;
419 	mesg->nr_conns = 0;
420 	mesg->syncid = ipvs->master_syncid;
421 	mesg->size = htons(sizeof(struct ip_vs_sync_mesg_v0));
422 	sb->head = (unsigned char *)mesg + sizeof(struct ip_vs_sync_mesg_v0);
423 	sb->end = (unsigned char *)mesg + ipvs->send_mesg_maxlen;
424 	sb->firstuse = jiffies;
425 	return sb;
426 }
427 
428 /* Check if connection is controlled by persistence */
in_persistence(struct ip_vs_conn * cp)429 static inline bool in_persistence(struct ip_vs_conn *cp)
430 {
431 	for (cp = cp->control; cp; cp = cp->control) {
432 		if (cp->flags & IP_VS_CONN_F_TEMPLATE)
433 			return true;
434 	}
435 	return false;
436 }
437 
438 /* Check if conn should be synced.
439  * pkts: conn packets, use sysctl_sync_threshold to avoid packet check
440  * - (1) sync_refresh_period: reduce sync rate. Additionally, retry
441  *	sync_retries times with period of sync_refresh_period/8
442  * - (2) if both sync_refresh_period and sync_period are 0 send sync only
443  *	for state changes or only once when pkts matches sync_threshold
444  * - (3) templates: rate can be reduced only with sync_refresh_period or
445  *	with (2)
446  */
ip_vs_sync_conn_needed(struct netns_ipvs * ipvs,struct ip_vs_conn * cp,int pkts)447 static int ip_vs_sync_conn_needed(struct netns_ipvs *ipvs,
448 				  struct ip_vs_conn *cp, int pkts)
449 {
450 	unsigned long orig = ACCESS_ONCE(cp->sync_endtime);
451 	unsigned long now = jiffies;
452 	unsigned long n = (now + cp->timeout) & ~3UL;
453 	unsigned int sync_refresh_period;
454 	int sync_period;
455 	int force;
456 
457 	/* Check if we sync in current state */
458 	if (unlikely(cp->flags & IP_VS_CONN_F_TEMPLATE))
459 		force = 0;
460 	else if (unlikely(sysctl_sync_persist_mode(ipvs) && in_persistence(cp)))
461 		return 0;
462 	else if (likely(cp->protocol == IPPROTO_TCP)) {
463 		if (!((1 << cp->state) &
464 		      ((1 << IP_VS_TCP_S_ESTABLISHED) |
465 		       (1 << IP_VS_TCP_S_FIN_WAIT) |
466 		       (1 << IP_VS_TCP_S_CLOSE) |
467 		       (1 << IP_VS_TCP_S_CLOSE_WAIT) |
468 		       (1 << IP_VS_TCP_S_TIME_WAIT))))
469 			return 0;
470 		force = cp->state != cp->old_state;
471 		if (force && cp->state != IP_VS_TCP_S_ESTABLISHED)
472 			goto set;
473 	} else if (unlikely(cp->protocol == IPPROTO_SCTP)) {
474 		if (!((1 << cp->state) &
475 		      ((1 << IP_VS_SCTP_S_ESTABLISHED) |
476 		       (1 << IP_VS_SCTP_S_SHUTDOWN_SENT) |
477 		       (1 << IP_VS_SCTP_S_SHUTDOWN_RECEIVED) |
478 		       (1 << IP_VS_SCTP_S_SHUTDOWN_ACK_SENT) |
479 		       (1 << IP_VS_SCTP_S_CLOSED))))
480 			return 0;
481 		force = cp->state != cp->old_state;
482 		if (force && cp->state != IP_VS_SCTP_S_ESTABLISHED)
483 			goto set;
484 	} else {
485 		/* UDP or another protocol with single state */
486 		force = 0;
487 	}
488 
489 	sync_refresh_period = sysctl_sync_refresh_period(ipvs);
490 	if (sync_refresh_period > 0) {
491 		long diff = n - orig;
492 		long min_diff = max(cp->timeout >> 1, 10UL * HZ);
493 
494 		/* Avoid sync if difference is below sync_refresh_period
495 		 * and below the half timeout.
496 		 */
497 		if (abs(diff) < min_t(long, sync_refresh_period, min_diff)) {
498 			int retries = orig & 3;
499 
500 			if (retries >= sysctl_sync_retries(ipvs))
501 				return 0;
502 			if (time_before(now, orig - cp->timeout +
503 					(sync_refresh_period >> 3)))
504 				return 0;
505 			n |= retries + 1;
506 		}
507 	}
508 	sync_period = sysctl_sync_period(ipvs);
509 	if (sync_period > 0) {
510 		if (!(cp->flags & IP_VS_CONN_F_TEMPLATE) &&
511 		    pkts % sync_period != sysctl_sync_threshold(ipvs))
512 			return 0;
513 	} else if (sync_refresh_period <= 0 &&
514 		   pkts != sysctl_sync_threshold(ipvs))
515 		return 0;
516 
517 set:
518 	cp->old_state = cp->state;
519 	n = cmpxchg(&cp->sync_endtime, orig, n);
520 	return n == orig || force;
521 }
522 
523 /*
524  *      Version 0 , could be switched in by sys_ctl.
525  *      Add an ip_vs_conn information into the current sync_buff.
526  */
ip_vs_sync_conn_v0(struct net * net,struct ip_vs_conn * cp,int pkts)527 static void ip_vs_sync_conn_v0(struct net *net, struct ip_vs_conn *cp,
528 			       int pkts)
529 {
530 	struct netns_ipvs *ipvs = net_ipvs(net);
531 	struct ip_vs_sync_mesg_v0 *m;
532 	struct ip_vs_sync_conn_v0 *s;
533 	struct ip_vs_sync_buff *buff;
534 	struct ipvs_master_sync_state *ms;
535 	int id;
536 	int len;
537 
538 	if (unlikely(cp->af != AF_INET))
539 		return;
540 	/* Do not sync ONE PACKET */
541 	if (cp->flags & IP_VS_CONN_F_ONE_PACKET)
542 		return;
543 
544 	if (!ip_vs_sync_conn_needed(ipvs, cp, pkts))
545 		return;
546 
547 	spin_lock_bh(&ipvs->sync_buff_lock);
548 	if (!(ipvs->sync_state & IP_VS_STATE_MASTER)) {
549 		spin_unlock_bh(&ipvs->sync_buff_lock);
550 		return;
551 	}
552 
553 	id = select_master_thread_id(ipvs, cp);
554 	ms = &ipvs->ms[id];
555 	buff = ms->sync_buff;
556 	if (buff) {
557 		m = (struct ip_vs_sync_mesg_v0 *) buff->mesg;
558 		/* Send buffer if it is for v1 */
559 		if (!m->nr_conns) {
560 			sb_queue_tail(ipvs, ms);
561 			ms->sync_buff = NULL;
562 			buff = NULL;
563 		}
564 	}
565 	if (!buff) {
566 		buff = ip_vs_sync_buff_create_v0(ipvs);
567 		if (!buff) {
568 			spin_unlock_bh(&ipvs->sync_buff_lock);
569 			pr_err("ip_vs_sync_buff_create failed.\n");
570 			return;
571 		}
572 		ms->sync_buff = buff;
573 	}
574 
575 	len = (cp->flags & IP_VS_CONN_F_SEQ_MASK) ? FULL_CONN_SIZE :
576 		SIMPLE_CONN_SIZE;
577 	m = (struct ip_vs_sync_mesg_v0 *) buff->mesg;
578 	s = (struct ip_vs_sync_conn_v0 *) buff->head;
579 
580 	/* copy members */
581 	s->reserved = 0;
582 	s->protocol = cp->protocol;
583 	s->cport = cp->cport;
584 	s->vport = cp->vport;
585 	s->dport = cp->dport;
586 	s->caddr = cp->caddr.ip;
587 	s->vaddr = cp->vaddr.ip;
588 	s->daddr = cp->daddr.ip;
589 	s->flags = htons(cp->flags & ~IP_VS_CONN_F_HASHED);
590 	s->state = htons(cp->state);
591 	if (cp->flags & IP_VS_CONN_F_SEQ_MASK) {
592 		struct ip_vs_sync_conn_options *opt =
593 			(struct ip_vs_sync_conn_options *)&s[1];
594 		memcpy(opt, &cp->in_seq, sizeof(*opt));
595 	}
596 
597 	m->nr_conns++;
598 	m->size = htons(ntohs(m->size) + len);
599 	buff->head += len;
600 
601 	/* check if there is a space for next one */
602 	if (buff->head + FULL_CONN_SIZE > buff->end) {
603 		sb_queue_tail(ipvs, ms);
604 		ms->sync_buff = NULL;
605 	}
606 	spin_unlock_bh(&ipvs->sync_buff_lock);
607 
608 	/* synchronize its controller if it has */
609 	cp = cp->control;
610 	if (cp) {
611 		if (cp->flags & IP_VS_CONN_F_TEMPLATE)
612 			pkts = atomic_add_return(1, &cp->in_pkts);
613 		else
614 			pkts = sysctl_sync_threshold(ipvs);
615 		ip_vs_sync_conn(net, cp, pkts);
616 	}
617 }
618 
619 /*
620  *      Add an ip_vs_conn information into the current sync_buff.
621  *      Called by ip_vs_in.
622  *      Sending Version 1 messages
623  */
ip_vs_sync_conn(struct net * net,struct ip_vs_conn * cp,int pkts)624 void ip_vs_sync_conn(struct net *net, struct ip_vs_conn *cp, int pkts)
625 {
626 	struct netns_ipvs *ipvs = net_ipvs(net);
627 	struct ip_vs_sync_mesg *m;
628 	union ip_vs_sync_conn *s;
629 	struct ip_vs_sync_buff *buff;
630 	struct ipvs_master_sync_state *ms;
631 	int id;
632 	__u8 *p;
633 	unsigned int len, pe_name_len, pad;
634 
635 	/* Handle old version of the protocol */
636 	if (sysctl_sync_ver(ipvs) == 0) {
637 		ip_vs_sync_conn_v0(net, cp, pkts);
638 		return;
639 	}
640 	/* Do not sync ONE PACKET */
641 	if (cp->flags & IP_VS_CONN_F_ONE_PACKET)
642 		goto control;
643 sloop:
644 	if (!ip_vs_sync_conn_needed(ipvs, cp, pkts))
645 		goto control;
646 
647 	/* Sanity checks */
648 	pe_name_len = 0;
649 	if (cp->pe_data_len) {
650 		if (!cp->pe_data || !cp->dest) {
651 			IP_VS_ERR_RL("SYNC, connection pe_data invalid\n");
652 			return;
653 		}
654 		pe_name_len = strnlen(cp->pe->name, IP_VS_PENAME_MAXLEN);
655 	}
656 
657 	spin_lock_bh(&ipvs->sync_buff_lock);
658 	if (!(ipvs->sync_state & IP_VS_STATE_MASTER)) {
659 		spin_unlock_bh(&ipvs->sync_buff_lock);
660 		return;
661 	}
662 
663 	id = select_master_thread_id(ipvs, cp);
664 	ms = &ipvs->ms[id];
665 
666 #ifdef CONFIG_IP_VS_IPV6
667 	if (cp->af == AF_INET6)
668 		len = sizeof(struct ip_vs_sync_v6);
669 	else
670 #endif
671 		len = sizeof(struct ip_vs_sync_v4);
672 
673 	if (cp->flags & IP_VS_CONN_F_SEQ_MASK)
674 		len += sizeof(struct ip_vs_sync_conn_options) + 2;
675 
676 	if (cp->pe_data_len)
677 		len += cp->pe_data_len + 2;	/* + Param hdr field */
678 	if (pe_name_len)
679 		len += pe_name_len + 2;
680 
681 	/* check if there is a space for this one  */
682 	pad = 0;
683 	buff = ms->sync_buff;
684 	if (buff) {
685 		m = buff->mesg;
686 		pad = (4 - (size_t) buff->head) & 3;
687 		/* Send buffer if it is for v0 */
688 		if (buff->head + len + pad > buff->end || m->reserved) {
689 			sb_queue_tail(ipvs, ms);
690 			ms->sync_buff = NULL;
691 			buff = NULL;
692 			pad = 0;
693 		}
694 	}
695 
696 	if (!buff) {
697 		buff = ip_vs_sync_buff_create(ipvs);
698 		if (!buff) {
699 			spin_unlock_bh(&ipvs->sync_buff_lock);
700 			pr_err("ip_vs_sync_buff_create failed.\n");
701 			return;
702 		}
703 		ms->sync_buff = buff;
704 		m = buff->mesg;
705 	}
706 
707 	p = buff->head;
708 	buff->head += pad + len;
709 	m->size = htons(ntohs(m->size) + pad + len);
710 	/* Add ev. padding from prev. sync_conn */
711 	while (pad--)
712 		*(p++) = 0;
713 
714 	s = (union ip_vs_sync_conn *)p;
715 
716 	/* Set message type  & copy members */
717 	s->v4.type = (cp->af == AF_INET6 ? STYPE_F_INET6 : 0);
718 	s->v4.ver_size = htons(len & SVER_MASK);	/* Version 0 */
719 	s->v4.flags = htonl(cp->flags & ~IP_VS_CONN_F_HASHED);
720 	s->v4.state = htons(cp->state);
721 	s->v4.protocol = cp->protocol;
722 	s->v4.cport = cp->cport;
723 	s->v4.vport = cp->vport;
724 	s->v4.dport = cp->dport;
725 	s->v4.fwmark = htonl(cp->fwmark);
726 	s->v4.timeout = htonl(cp->timeout / HZ);
727 	m->nr_conns++;
728 
729 #ifdef CONFIG_IP_VS_IPV6
730 	if (cp->af == AF_INET6) {
731 		p += sizeof(struct ip_vs_sync_v6);
732 		s->v6.caddr = cp->caddr.in6;
733 		s->v6.vaddr = cp->vaddr.in6;
734 		s->v6.daddr = cp->daddr.in6;
735 	} else
736 #endif
737 	{
738 		p += sizeof(struct ip_vs_sync_v4);	/* options ptr */
739 		s->v4.caddr = cp->caddr.ip;
740 		s->v4.vaddr = cp->vaddr.ip;
741 		s->v4.daddr = cp->daddr.ip;
742 	}
743 	if (cp->flags & IP_VS_CONN_F_SEQ_MASK) {
744 		*(p++) = IPVS_OPT_SEQ_DATA;
745 		*(p++) = sizeof(struct ip_vs_sync_conn_options);
746 		hton_seq((struct ip_vs_seq *)p, &cp->in_seq);
747 		p += sizeof(struct ip_vs_seq);
748 		hton_seq((struct ip_vs_seq *)p, &cp->out_seq);
749 		p += sizeof(struct ip_vs_seq);
750 	}
751 	/* Handle pe data */
752 	if (cp->pe_data_len && cp->pe_data) {
753 		*(p++) = IPVS_OPT_PE_DATA;
754 		*(p++) = cp->pe_data_len;
755 		memcpy(p, cp->pe_data, cp->pe_data_len);
756 		p += cp->pe_data_len;
757 		if (pe_name_len) {
758 			/* Add PE_NAME */
759 			*(p++) = IPVS_OPT_PE_NAME;
760 			*(p++) = pe_name_len;
761 			memcpy(p, cp->pe->name, pe_name_len);
762 			p += pe_name_len;
763 		}
764 	}
765 
766 	spin_unlock_bh(&ipvs->sync_buff_lock);
767 
768 control:
769 	/* synchronize its controller if it has */
770 	cp = cp->control;
771 	if (!cp)
772 		return;
773 	if (cp->flags & IP_VS_CONN_F_TEMPLATE)
774 		pkts = atomic_add_return(1, &cp->in_pkts);
775 	else
776 		pkts = sysctl_sync_threshold(ipvs);
777 	goto sloop;
778 }
779 
780 /*
781  *  fill_param used by version 1
782  */
783 static inline int
ip_vs_conn_fill_param_sync(struct net * net,int af,union ip_vs_sync_conn * sc,struct ip_vs_conn_param * p,__u8 * pe_data,unsigned int pe_data_len,__u8 * pe_name,unsigned int pe_name_len)784 ip_vs_conn_fill_param_sync(struct net *net, int af, union ip_vs_sync_conn *sc,
785 			   struct ip_vs_conn_param *p,
786 			   __u8 *pe_data, unsigned int pe_data_len,
787 			   __u8 *pe_name, unsigned int pe_name_len)
788 {
789 #ifdef CONFIG_IP_VS_IPV6
790 	if (af == AF_INET6)
791 		ip_vs_conn_fill_param(net, af, sc->v6.protocol,
792 				      (const union nf_inet_addr *)&sc->v6.caddr,
793 				      sc->v6.cport,
794 				      (const union nf_inet_addr *)&sc->v6.vaddr,
795 				      sc->v6.vport, p);
796 	else
797 #endif
798 		ip_vs_conn_fill_param(net, af, sc->v4.protocol,
799 				      (const union nf_inet_addr *)&sc->v4.caddr,
800 				      sc->v4.cport,
801 				      (const union nf_inet_addr *)&sc->v4.vaddr,
802 				      sc->v4.vport, p);
803 	/* Handle pe data */
804 	if (pe_data_len) {
805 		if (pe_name_len) {
806 			char buff[IP_VS_PENAME_MAXLEN+1];
807 
808 			memcpy(buff, pe_name, pe_name_len);
809 			buff[pe_name_len]=0;
810 			p->pe = __ip_vs_pe_getbyname(buff);
811 			if (!p->pe) {
812 				IP_VS_DBG(3, "BACKUP, no %s engine found/loaded\n",
813 					     buff);
814 				return 1;
815 			}
816 		} else {
817 			IP_VS_ERR_RL("BACKUP, Invalid PE parameters\n");
818 			return 1;
819 		}
820 
821 		p->pe_data = kmemdup(pe_data, pe_data_len, GFP_ATOMIC);
822 		if (!p->pe_data) {
823 			if (p->pe->module)
824 				module_put(p->pe->module);
825 			return -ENOMEM;
826 		}
827 		p->pe_data_len = pe_data_len;
828 	}
829 	return 0;
830 }
831 
832 /*
833  *  Connection Add / Update.
834  *  Common for version 0 and 1 reception of backup sync_conns.
835  *  Param: ...
836  *         timeout is in sec.
837  */
ip_vs_proc_conn(struct net * net,struct ip_vs_conn_param * param,unsigned int flags,unsigned int state,unsigned int protocol,unsigned int type,const union nf_inet_addr * daddr,__be16 dport,unsigned long timeout,__u32 fwmark,struct ip_vs_sync_conn_options * opt)838 static void ip_vs_proc_conn(struct net *net, struct ip_vs_conn_param *param,
839 			    unsigned int flags, unsigned int state,
840 			    unsigned int protocol, unsigned int type,
841 			    const union nf_inet_addr *daddr, __be16 dport,
842 			    unsigned long timeout, __u32 fwmark,
843 			    struct ip_vs_sync_conn_options *opt)
844 {
845 	struct ip_vs_dest *dest;
846 	struct ip_vs_conn *cp;
847 	struct netns_ipvs *ipvs = net_ipvs(net);
848 
849 	if (!(flags & IP_VS_CONN_F_TEMPLATE))
850 		cp = ip_vs_conn_in_get(param);
851 	else
852 		cp = ip_vs_ct_in_get(param);
853 
854 	if (cp) {
855 		/* Free pe_data */
856 		kfree(param->pe_data);
857 
858 		dest = cp->dest;
859 		spin_lock_bh(&cp->lock);
860 		if ((cp->flags ^ flags) & IP_VS_CONN_F_INACTIVE &&
861 		    !(flags & IP_VS_CONN_F_TEMPLATE) && dest) {
862 			if (flags & IP_VS_CONN_F_INACTIVE) {
863 				atomic_dec(&dest->activeconns);
864 				atomic_inc(&dest->inactconns);
865 			} else {
866 				atomic_inc(&dest->activeconns);
867 				atomic_dec(&dest->inactconns);
868 			}
869 		}
870 		flags &= IP_VS_CONN_F_BACKUP_UPD_MASK;
871 		flags |= cp->flags & ~IP_VS_CONN_F_BACKUP_UPD_MASK;
872 		cp->flags = flags;
873 		spin_unlock_bh(&cp->lock);
874 		if (!dest)
875 			ip_vs_try_bind_dest(cp);
876 	} else {
877 		/*
878 		 * Find the appropriate destination for the connection.
879 		 * If it is not found the connection will remain unbound
880 		 * but still handled.
881 		 */
882 		rcu_read_lock();
883 		/* This function is only invoked by the synchronization
884 		 * code. We do not currently support heterogeneous pools
885 		 * with synchronization, so we can make the assumption that
886 		 * the svc_af is the same as the dest_af
887 		 */
888 		dest = ip_vs_find_dest(net, type, type, daddr, dport,
889 				       param->vaddr, param->vport, protocol,
890 				       fwmark, flags);
891 
892 		cp = ip_vs_conn_new(param, type, daddr, dport, flags, dest,
893 				    fwmark);
894 		rcu_read_unlock();
895 		if (!cp) {
896 			kfree(param->pe_data);
897 			IP_VS_DBG(2, "BACKUP, add new conn. failed\n");
898 			return;
899 		}
900 	}
901 
902 	if (opt)
903 		memcpy(&cp->in_seq, opt, sizeof(*opt));
904 	atomic_set(&cp->in_pkts, sysctl_sync_threshold(ipvs));
905 	cp->state = state;
906 	cp->old_state = cp->state;
907 	/*
908 	 * For Ver 0 messages style
909 	 *  - Not possible to recover the right timeout for templates
910 	 *  - can not find the right fwmark
911 	 *    virtual service. If needed, we can do it for
912 	 *    non-fwmark persistent services.
913 	 * Ver 1 messages style.
914 	 *  - No problem.
915 	 */
916 	if (timeout) {
917 		if (timeout > MAX_SCHEDULE_TIMEOUT / HZ)
918 			timeout = MAX_SCHEDULE_TIMEOUT / HZ;
919 		cp->timeout = timeout*HZ;
920 	} else {
921 		struct ip_vs_proto_data *pd;
922 
923 		pd = ip_vs_proto_data_get(net, protocol);
924 		if (!(flags & IP_VS_CONN_F_TEMPLATE) && pd && pd->timeout_table)
925 			cp->timeout = pd->timeout_table[state];
926 		else
927 			cp->timeout = (3*60*HZ);
928 	}
929 	ip_vs_conn_put(cp);
930 }
931 
932 /*
933  *  Process received multicast message for Version 0
934  */
ip_vs_process_message_v0(struct net * net,const char * buffer,const size_t buflen)935 static void ip_vs_process_message_v0(struct net *net, const char *buffer,
936 				     const size_t buflen)
937 {
938 	struct ip_vs_sync_mesg_v0 *m = (struct ip_vs_sync_mesg_v0 *)buffer;
939 	struct ip_vs_sync_conn_v0 *s;
940 	struct ip_vs_sync_conn_options *opt;
941 	struct ip_vs_protocol *pp;
942 	struct ip_vs_conn_param param;
943 	char *p;
944 	int i;
945 
946 	p = (char *)buffer + sizeof(struct ip_vs_sync_mesg_v0);
947 	for (i=0; i<m->nr_conns; i++) {
948 		unsigned int flags, state;
949 
950 		if (p + SIMPLE_CONN_SIZE > buffer+buflen) {
951 			IP_VS_ERR_RL("BACKUP v0, bogus conn\n");
952 			return;
953 		}
954 		s = (struct ip_vs_sync_conn_v0 *) p;
955 		flags = ntohs(s->flags) | IP_VS_CONN_F_SYNC;
956 		flags &= ~IP_VS_CONN_F_HASHED;
957 		if (flags & IP_VS_CONN_F_SEQ_MASK) {
958 			opt = (struct ip_vs_sync_conn_options *)&s[1];
959 			p += FULL_CONN_SIZE;
960 			if (p > buffer+buflen) {
961 				IP_VS_ERR_RL("BACKUP v0, Dropping buffer bogus conn options\n");
962 				return;
963 			}
964 		} else {
965 			opt = NULL;
966 			p += SIMPLE_CONN_SIZE;
967 		}
968 
969 		state = ntohs(s->state);
970 		if (!(flags & IP_VS_CONN_F_TEMPLATE)) {
971 			pp = ip_vs_proto_get(s->protocol);
972 			if (!pp) {
973 				IP_VS_DBG(2, "BACKUP v0, Unsupported protocol %u\n",
974 					s->protocol);
975 				continue;
976 			}
977 			if (state >= pp->num_states) {
978 				IP_VS_DBG(2, "BACKUP v0, Invalid %s state %u\n",
979 					pp->name, state);
980 				continue;
981 			}
982 		} else {
983 			/* protocol in templates is not used for state/timeout */
984 			if (state > 0) {
985 				IP_VS_DBG(2, "BACKUP v0, Invalid template state %u\n",
986 					state);
987 				state = 0;
988 			}
989 		}
990 
991 		ip_vs_conn_fill_param(net, AF_INET, s->protocol,
992 				      (const union nf_inet_addr *)&s->caddr,
993 				      s->cport,
994 				      (const union nf_inet_addr *)&s->vaddr,
995 				      s->vport, &param);
996 
997 		/* Send timeout as Zero */
998 		ip_vs_proc_conn(net, &param, flags, state, s->protocol, AF_INET,
999 				(union nf_inet_addr *)&s->daddr, s->dport,
1000 				0, 0, opt);
1001 	}
1002 }
1003 
1004 /*
1005  * Handle options
1006  */
ip_vs_proc_seqopt(__u8 * p,unsigned int plen,__u32 * opt_flags,struct ip_vs_sync_conn_options * opt)1007 static inline int ip_vs_proc_seqopt(__u8 *p, unsigned int plen,
1008 				    __u32 *opt_flags,
1009 				    struct ip_vs_sync_conn_options *opt)
1010 {
1011 	struct ip_vs_sync_conn_options *topt;
1012 
1013 	topt = (struct ip_vs_sync_conn_options *)p;
1014 
1015 	if (plen != sizeof(struct ip_vs_sync_conn_options)) {
1016 		IP_VS_DBG(2, "BACKUP, bogus conn options length\n");
1017 		return -EINVAL;
1018 	}
1019 	if (*opt_flags & IPVS_OPT_F_SEQ_DATA) {
1020 		IP_VS_DBG(2, "BACKUP, conn options found twice\n");
1021 		return -EINVAL;
1022 	}
1023 	ntoh_seq(&topt->in_seq, &opt->in_seq);
1024 	ntoh_seq(&topt->out_seq, &opt->out_seq);
1025 	*opt_flags |= IPVS_OPT_F_SEQ_DATA;
1026 	return 0;
1027 }
1028 
ip_vs_proc_str(__u8 * p,unsigned int plen,unsigned int * data_len,__u8 ** data,unsigned int maxlen,__u32 * opt_flags,__u32 flag)1029 static int ip_vs_proc_str(__u8 *p, unsigned int plen, unsigned int *data_len,
1030 			  __u8 **data, unsigned int maxlen,
1031 			  __u32 *opt_flags, __u32 flag)
1032 {
1033 	if (plen > maxlen) {
1034 		IP_VS_DBG(2, "BACKUP, bogus par.data len > %d\n", maxlen);
1035 		return -EINVAL;
1036 	}
1037 	if (*opt_flags & flag) {
1038 		IP_VS_DBG(2, "BACKUP, Par.data found twice 0x%x\n", flag);
1039 		return -EINVAL;
1040 	}
1041 	*data_len = plen;
1042 	*data = p;
1043 	*opt_flags |= flag;
1044 	return 0;
1045 }
1046 /*
1047  *   Process a Version 1 sync. connection
1048  */
ip_vs_proc_sync_conn(struct net * net,__u8 * p,__u8 * msg_end)1049 static inline int ip_vs_proc_sync_conn(struct net *net, __u8 *p, __u8 *msg_end)
1050 {
1051 	struct ip_vs_sync_conn_options opt;
1052 	union  ip_vs_sync_conn *s;
1053 	struct ip_vs_protocol *pp;
1054 	struct ip_vs_conn_param param;
1055 	__u32 flags;
1056 	unsigned int af, state, pe_data_len=0, pe_name_len=0;
1057 	__u8 *pe_data=NULL, *pe_name=NULL;
1058 	__u32 opt_flags=0;
1059 	int retc=0;
1060 
1061 	s = (union ip_vs_sync_conn *) p;
1062 
1063 	if (s->v6.type & STYPE_F_INET6) {
1064 #ifdef CONFIG_IP_VS_IPV6
1065 		af = AF_INET6;
1066 		p += sizeof(struct ip_vs_sync_v6);
1067 #else
1068 		IP_VS_DBG(3,"BACKUP, IPv6 msg received, and IPVS is not compiled for IPv6\n");
1069 		retc = 10;
1070 		goto out;
1071 #endif
1072 	} else if (!s->v4.type) {
1073 		af = AF_INET;
1074 		p += sizeof(struct ip_vs_sync_v4);
1075 	} else {
1076 		return -10;
1077 	}
1078 	if (p > msg_end)
1079 		return -20;
1080 
1081 	/* Process optional params check Type & Len. */
1082 	while (p < msg_end) {
1083 		int ptype;
1084 		int plen;
1085 
1086 		if (p+2 > msg_end)
1087 			return -30;
1088 		ptype = *(p++);
1089 		plen  = *(p++);
1090 
1091 		if (!plen || ((p + plen) > msg_end))
1092 			return -40;
1093 		/* Handle seq option  p = param data */
1094 		switch (ptype & ~IPVS_OPT_F_PARAM) {
1095 		case IPVS_OPT_SEQ_DATA:
1096 			if (ip_vs_proc_seqopt(p, plen, &opt_flags, &opt))
1097 				return -50;
1098 			break;
1099 
1100 		case IPVS_OPT_PE_DATA:
1101 			if (ip_vs_proc_str(p, plen, &pe_data_len, &pe_data,
1102 					   IP_VS_PEDATA_MAXLEN, &opt_flags,
1103 					   IPVS_OPT_F_PE_DATA))
1104 				return -60;
1105 			break;
1106 
1107 		case IPVS_OPT_PE_NAME:
1108 			if (ip_vs_proc_str(p, plen,&pe_name_len, &pe_name,
1109 					   IP_VS_PENAME_MAXLEN, &opt_flags,
1110 					   IPVS_OPT_F_PE_NAME))
1111 				return -70;
1112 			break;
1113 
1114 		default:
1115 			/* Param data mandatory ? */
1116 			if (!(ptype & IPVS_OPT_F_PARAM)) {
1117 				IP_VS_DBG(3, "BACKUP, Unknown mandatory param %d found\n",
1118 					  ptype & ~IPVS_OPT_F_PARAM);
1119 				retc = 20;
1120 				goto out;
1121 			}
1122 		}
1123 		p += plen;  /* Next option */
1124 	}
1125 
1126 	/* Get flags and Mask off unsupported */
1127 	flags  = ntohl(s->v4.flags) & IP_VS_CONN_F_BACKUP_MASK;
1128 	flags |= IP_VS_CONN_F_SYNC;
1129 	state = ntohs(s->v4.state);
1130 
1131 	if (!(flags & IP_VS_CONN_F_TEMPLATE)) {
1132 		pp = ip_vs_proto_get(s->v4.protocol);
1133 		if (!pp) {
1134 			IP_VS_DBG(3,"BACKUP, Unsupported protocol %u\n",
1135 				s->v4.protocol);
1136 			retc = 30;
1137 			goto out;
1138 		}
1139 		if (state >= pp->num_states) {
1140 			IP_VS_DBG(3, "BACKUP, Invalid %s state %u\n",
1141 				pp->name, state);
1142 			retc = 40;
1143 			goto out;
1144 		}
1145 	} else {
1146 		/* protocol in templates is not used for state/timeout */
1147 		if (state > 0) {
1148 			IP_VS_DBG(3, "BACKUP, Invalid template state %u\n",
1149 				state);
1150 			state = 0;
1151 		}
1152 	}
1153 	if (ip_vs_conn_fill_param_sync(net, af, s, &param, pe_data,
1154 				       pe_data_len, pe_name, pe_name_len)) {
1155 		retc = 50;
1156 		goto out;
1157 	}
1158 	/* If only IPv4, just silent skip IPv6 */
1159 	if (af == AF_INET)
1160 		ip_vs_proc_conn(net, &param, flags, state, s->v4.protocol, af,
1161 				(union nf_inet_addr *)&s->v4.daddr, s->v4.dport,
1162 				ntohl(s->v4.timeout), ntohl(s->v4.fwmark),
1163 				(opt_flags & IPVS_OPT_F_SEQ_DATA ? &opt : NULL)
1164 				);
1165 #ifdef CONFIG_IP_VS_IPV6
1166 	else
1167 		ip_vs_proc_conn(net, &param, flags, state, s->v6.protocol, af,
1168 				(union nf_inet_addr *)&s->v6.daddr, s->v6.dport,
1169 				ntohl(s->v6.timeout), ntohl(s->v6.fwmark),
1170 				(opt_flags & IPVS_OPT_F_SEQ_DATA ? &opt : NULL)
1171 				);
1172 #endif
1173 	return 0;
1174 	/* Error exit */
1175 out:
1176 	IP_VS_DBG(2, "BACKUP, Single msg dropped err:%d\n", retc);
1177 	return retc;
1178 
1179 }
1180 /*
1181  *      Process received multicast message and create the corresponding
1182  *      ip_vs_conn entries.
1183  *      Handles Version 0 & 1
1184  */
ip_vs_process_message(struct net * net,__u8 * buffer,const size_t buflen)1185 static void ip_vs_process_message(struct net *net, __u8 *buffer,
1186 				  const size_t buflen)
1187 {
1188 	struct netns_ipvs *ipvs = net_ipvs(net);
1189 	struct ip_vs_sync_mesg *m2 = (struct ip_vs_sync_mesg *)buffer;
1190 	__u8 *p, *msg_end;
1191 	int i, nr_conns;
1192 
1193 	if (buflen < sizeof(struct ip_vs_sync_mesg_v0)) {
1194 		IP_VS_DBG(2, "BACKUP, message header too short\n");
1195 		return;
1196 	}
1197 
1198 	if (buflen != ntohs(m2->size)) {
1199 		IP_VS_DBG(2, "BACKUP, bogus message size\n");
1200 		return;
1201 	}
1202 	/* SyncID sanity check */
1203 	if (ipvs->backup_syncid != 0 && m2->syncid != ipvs->backup_syncid) {
1204 		IP_VS_DBG(7, "BACKUP, Ignoring syncid = %d\n", m2->syncid);
1205 		return;
1206 	}
1207 	/* Handle version 1  message */
1208 	if ((m2->version == SYNC_PROTO_VER) && (m2->reserved == 0)
1209 	    && (m2->spare == 0)) {
1210 
1211 		msg_end = buffer + sizeof(struct ip_vs_sync_mesg);
1212 		nr_conns = m2->nr_conns;
1213 
1214 		for (i=0; i<nr_conns; i++) {
1215 			union ip_vs_sync_conn *s;
1216 			unsigned int size;
1217 			int retc;
1218 
1219 			p = msg_end;
1220 			if (p + sizeof(s->v4) > buffer+buflen) {
1221 				IP_VS_ERR_RL("BACKUP, Dropping buffer, to small\n");
1222 				return;
1223 			}
1224 			s = (union ip_vs_sync_conn *)p;
1225 			size = ntohs(s->v4.ver_size) & SVER_MASK;
1226 			msg_end = p + size;
1227 			/* Basic sanity checks */
1228 			if (msg_end  > buffer+buflen) {
1229 				IP_VS_ERR_RL("BACKUP, Dropping buffer, msg > buffer\n");
1230 				return;
1231 			}
1232 			if (ntohs(s->v4.ver_size) >> SVER_SHIFT) {
1233 				IP_VS_ERR_RL("BACKUP, Dropping buffer, Unknown version %d\n",
1234 					      ntohs(s->v4.ver_size) >> SVER_SHIFT);
1235 				return;
1236 			}
1237 			/* Process a single sync_conn */
1238 			retc = ip_vs_proc_sync_conn(net, p, msg_end);
1239 			if (retc < 0) {
1240 				IP_VS_ERR_RL("BACKUP, Dropping buffer, Err: %d in decoding\n",
1241 					     retc);
1242 				return;
1243 			}
1244 			/* Make sure we have 32 bit alignment */
1245 			msg_end = p + ((size + 3) & ~3);
1246 		}
1247 	} else {
1248 		/* Old type of message */
1249 		ip_vs_process_message_v0(net, buffer, buflen);
1250 		return;
1251 	}
1252 }
1253 
1254 
1255 /*
1256  *      Setup sndbuf (mode=1) or rcvbuf (mode=0)
1257  */
set_sock_size(struct sock * sk,int mode,int val)1258 static void set_sock_size(struct sock *sk, int mode, int val)
1259 {
1260 	/* setsockopt(sock, SOL_SOCKET, SO_SNDBUF, &val, sizeof(val)); */
1261 	/* setsockopt(sock, SOL_SOCKET, SO_RCVBUF, &val, sizeof(val)); */
1262 	lock_sock(sk);
1263 	if (mode) {
1264 		val = clamp_t(int, val, (SOCK_MIN_SNDBUF + 1) / 2,
1265 			      sysctl_wmem_max);
1266 		sk->sk_sndbuf = val * 2;
1267 		sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
1268 	} else {
1269 		val = clamp_t(int, val, (SOCK_MIN_RCVBUF + 1) / 2,
1270 			      sysctl_rmem_max);
1271 		sk->sk_rcvbuf = val * 2;
1272 		sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
1273 	}
1274 	release_sock(sk);
1275 }
1276 
1277 /*
1278  *      Setup loopback of outgoing multicasts on a sending socket
1279  */
set_mcast_loop(struct sock * sk,u_char loop)1280 static void set_mcast_loop(struct sock *sk, u_char loop)
1281 {
1282 	struct inet_sock *inet = inet_sk(sk);
1283 
1284 	/* setsockopt(sock, SOL_IP, IP_MULTICAST_LOOP, &loop, sizeof(loop)); */
1285 	lock_sock(sk);
1286 	inet->mc_loop = loop ? 1 : 0;
1287 	release_sock(sk);
1288 }
1289 
1290 /*
1291  *      Specify TTL for outgoing multicasts on a sending socket
1292  */
set_mcast_ttl(struct sock * sk,u_char ttl)1293 static void set_mcast_ttl(struct sock *sk, u_char ttl)
1294 {
1295 	struct inet_sock *inet = inet_sk(sk);
1296 
1297 	/* setsockopt(sock, SOL_IP, IP_MULTICAST_TTL, &ttl, sizeof(ttl)); */
1298 	lock_sock(sk);
1299 	inet->mc_ttl = ttl;
1300 	release_sock(sk);
1301 }
1302 
1303 /*
1304  *      Specifiy default interface for outgoing multicasts
1305  */
set_mcast_if(struct sock * sk,char * ifname)1306 static int set_mcast_if(struct sock *sk, char *ifname)
1307 {
1308 	struct net_device *dev;
1309 	struct inet_sock *inet = inet_sk(sk);
1310 	struct net *net = sock_net(sk);
1311 
1312 	dev = __dev_get_by_name(net, ifname);
1313 	if (!dev)
1314 		return -ENODEV;
1315 
1316 	if (sk->sk_bound_dev_if && dev->ifindex != sk->sk_bound_dev_if)
1317 		return -EINVAL;
1318 
1319 	lock_sock(sk);
1320 	inet->mc_index = dev->ifindex;
1321 	/*  inet->mc_addr  = 0; */
1322 	release_sock(sk);
1323 
1324 	return 0;
1325 }
1326 
1327 
1328 /*
1329  *	Set the maximum length of sync message according to the
1330  *	specified interface's MTU.
1331  */
set_sync_mesg_maxlen(struct net * net,int sync_state)1332 static int set_sync_mesg_maxlen(struct net *net, int sync_state)
1333 {
1334 	struct netns_ipvs *ipvs = net_ipvs(net);
1335 	struct net_device *dev;
1336 	int num;
1337 
1338 	if (sync_state == IP_VS_STATE_MASTER) {
1339 		dev = __dev_get_by_name(net, ipvs->master_mcast_ifn);
1340 		if (!dev)
1341 			return -ENODEV;
1342 
1343 		num = (dev->mtu - sizeof(struct iphdr) -
1344 		       sizeof(struct udphdr) -
1345 		       SYNC_MESG_HEADER_LEN - 20) / SIMPLE_CONN_SIZE;
1346 		ipvs->send_mesg_maxlen = SYNC_MESG_HEADER_LEN +
1347 			SIMPLE_CONN_SIZE * min(num, MAX_CONNS_PER_SYNCBUFF);
1348 		IP_VS_DBG(7, "setting the maximum length of sync sending "
1349 			  "message %d.\n", ipvs->send_mesg_maxlen);
1350 	} else if (sync_state == IP_VS_STATE_BACKUP) {
1351 		dev = __dev_get_by_name(net, ipvs->backup_mcast_ifn);
1352 		if (!dev)
1353 			return -ENODEV;
1354 
1355 		ipvs->recv_mesg_maxlen = dev->mtu -
1356 			sizeof(struct iphdr) - sizeof(struct udphdr);
1357 		IP_VS_DBG(7, "setting the maximum length of sync receiving "
1358 			  "message %d.\n", ipvs->recv_mesg_maxlen);
1359 	}
1360 
1361 	return 0;
1362 }
1363 
1364 
1365 /*
1366  *      Join a multicast group.
1367  *      the group is specified by a class D multicast address 224.0.0.0/8
1368  *      in the in_addr structure passed in as a parameter.
1369  */
1370 static int
join_mcast_group(struct sock * sk,struct in_addr * addr,char * ifname)1371 join_mcast_group(struct sock *sk, struct in_addr *addr, char *ifname)
1372 {
1373 	struct net *net = sock_net(sk);
1374 	struct ip_mreqn mreq;
1375 	struct net_device *dev;
1376 	int ret;
1377 
1378 	memset(&mreq, 0, sizeof(mreq));
1379 	memcpy(&mreq.imr_multiaddr, addr, sizeof(struct in_addr));
1380 
1381 	dev = __dev_get_by_name(net, ifname);
1382 	if (!dev)
1383 		return -ENODEV;
1384 	if (sk->sk_bound_dev_if && dev->ifindex != sk->sk_bound_dev_if)
1385 		return -EINVAL;
1386 
1387 	mreq.imr_ifindex = dev->ifindex;
1388 
1389 	lock_sock(sk);
1390 	ret = ip_mc_join_group(sk, &mreq);
1391 	release_sock(sk);
1392 
1393 	return ret;
1394 }
1395 
1396 
bind_mcastif_addr(struct socket * sock,char * ifname)1397 static int bind_mcastif_addr(struct socket *sock, char *ifname)
1398 {
1399 	struct net *net = sock_net(sock->sk);
1400 	struct net_device *dev;
1401 	__be32 addr;
1402 	struct sockaddr_in sin;
1403 
1404 	dev = __dev_get_by_name(net, ifname);
1405 	if (!dev)
1406 		return -ENODEV;
1407 
1408 	addr = inet_select_addr(dev, 0, RT_SCOPE_UNIVERSE);
1409 	if (!addr)
1410 		pr_err("You probably need to specify IP address on "
1411 		       "multicast interface.\n");
1412 
1413 	IP_VS_DBG(7, "binding socket with (%s) %pI4\n",
1414 		  ifname, &addr);
1415 
1416 	/* Now bind the socket with the address of multicast interface */
1417 	sin.sin_family	     = AF_INET;
1418 	sin.sin_addr.s_addr  = addr;
1419 	sin.sin_port         = 0;
1420 
1421 	return sock->ops->bind(sock, (struct sockaddr*)&sin, sizeof(sin));
1422 }
1423 
1424 /*
1425  *      Set up sending multicast socket over UDP
1426  */
make_send_sock(struct net * net,int id)1427 static struct socket *make_send_sock(struct net *net, int id)
1428 {
1429 	struct netns_ipvs *ipvs = net_ipvs(net);
1430 	/* multicast addr */
1431 	struct sockaddr_in mcast_addr = {
1432 		.sin_family		= AF_INET,
1433 		.sin_port		= cpu_to_be16(IP_VS_SYNC_PORT + id),
1434 		.sin_addr.s_addr	= cpu_to_be32(IP_VS_SYNC_GROUP),
1435 	};
1436 	struct socket *sock;
1437 	int result;
1438 
1439 	/* First create a socket move it to right name space later */
1440 	result = sock_create_kern(PF_INET, SOCK_DGRAM, IPPROTO_UDP, &sock);
1441 	if (result < 0) {
1442 		pr_err("Error during creation of socket; terminating\n");
1443 		return ERR_PTR(result);
1444 	}
1445 	/*
1446 	 * Kernel sockets that are a part of a namespace, should not
1447 	 * hold a reference to a namespace in order to allow to stop it.
1448 	 * After sk_change_net should be released using sk_release_kernel.
1449 	 */
1450 	sk_change_net(sock->sk, net);
1451 	result = set_mcast_if(sock->sk, ipvs->master_mcast_ifn);
1452 	if (result < 0) {
1453 		pr_err("Error setting outbound mcast interface\n");
1454 		goto error;
1455 	}
1456 
1457 	set_mcast_loop(sock->sk, 0);
1458 	set_mcast_ttl(sock->sk, 1);
1459 	result = sysctl_sync_sock_size(ipvs);
1460 	if (result > 0)
1461 		set_sock_size(sock->sk, 1, result);
1462 
1463 	result = bind_mcastif_addr(sock, ipvs->master_mcast_ifn);
1464 	if (result < 0) {
1465 		pr_err("Error binding address of the mcast interface\n");
1466 		goto error;
1467 	}
1468 
1469 	result = sock->ops->connect(sock, (struct sockaddr *) &mcast_addr,
1470 			sizeof(struct sockaddr), 0);
1471 	if (result < 0) {
1472 		pr_err("Error connecting to the multicast addr\n");
1473 		goto error;
1474 	}
1475 
1476 	return sock;
1477 
1478 error:
1479 	sk_release_kernel(sock->sk);
1480 	return ERR_PTR(result);
1481 }
1482 
1483 
1484 /*
1485  *      Set up receiving multicast socket over UDP
1486  */
make_receive_sock(struct net * net,int id)1487 static struct socket *make_receive_sock(struct net *net, int id)
1488 {
1489 	struct netns_ipvs *ipvs = net_ipvs(net);
1490 	/* multicast addr */
1491 	struct sockaddr_in mcast_addr = {
1492 		.sin_family		= AF_INET,
1493 		.sin_port		= cpu_to_be16(IP_VS_SYNC_PORT + id),
1494 		.sin_addr.s_addr	= cpu_to_be32(IP_VS_SYNC_GROUP),
1495 	};
1496 	struct socket *sock;
1497 	int result;
1498 
1499 	/* First create a socket */
1500 	result = sock_create_kern(PF_INET, SOCK_DGRAM, IPPROTO_UDP, &sock);
1501 	if (result < 0) {
1502 		pr_err("Error during creation of socket; terminating\n");
1503 		return ERR_PTR(result);
1504 	}
1505 	/*
1506 	 * Kernel sockets that are a part of a namespace, should not
1507 	 * hold a reference to a namespace in order to allow to stop it.
1508 	 * After sk_change_net should be released using sk_release_kernel.
1509 	 */
1510 	sk_change_net(sock->sk, net);
1511 	/* it is equivalent to the REUSEADDR option in user-space */
1512 	sock->sk->sk_reuse = SK_CAN_REUSE;
1513 	result = sysctl_sync_sock_size(ipvs);
1514 	if (result > 0)
1515 		set_sock_size(sock->sk, 0, result);
1516 
1517 	result = sock->ops->bind(sock, (struct sockaddr *) &mcast_addr,
1518 			sizeof(struct sockaddr));
1519 	if (result < 0) {
1520 		pr_err("Error binding to the multicast addr\n");
1521 		goto error;
1522 	}
1523 
1524 	/* join the multicast group */
1525 	result = join_mcast_group(sock->sk,
1526 			(struct in_addr *) &mcast_addr.sin_addr,
1527 			ipvs->backup_mcast_ifn);
1528 	if (result < 0) {
1529 		pr_err("Error joining to the multicast group\n");
1530 		goto error;
1531 	}
1532 
1533 	return sock;
1534 
1535 error:
1536 	sk_release_kernel(sock->sk);
1537 	return ERR_PTR(result);
1538 }
1539 
1540 
1541 static int
ip_vs_send_async(struct socket * sock,const char * buffer,const size_t length)1542 ip_vs_send_async(struct socket *sock, const char *buffer, const size_t length)
1543 {
1544 	struct msghdr	msg = {.msg_flags = MSG_DONTWAIT|MSG_NOSIGNAL};
1545 	struct kvec	iov;
1546 	int		len;
1547 
1548 	EnterFunction(7);
1549 	iov.iov_base     = (void *)buffer;
1550 	iov.iov_len      = length;
1551 
1552 	len = kernel_sendmsg(sock, &msg, &iov, 1, (size_t)(length));
1553 
1554 	LeaveFunction(7);
1555 	return len;
1556 }
1557 
1558 static int
ip_vs_send_sync_msg(struct socket * sock,struct ip_vs_sync_mesg * msg)1559 ip_vs_send_sync_msg(struct socket *sock, struct ip_vs_sync_mesg *msg)
1560 {
1561 	int msize;
1562 	int ret;
1563 
1564 	msize = ntohs(msg->size);
1565 
1566 	ret = ip_vs_send_async(sock, (char *)msg, msize);
1567 	if (ret >= 0 || ret == -EAGAIN)
1568 		return ret;
1569 	pr_err("ip_vs_send_async error %d\n", ret);
1570 	return 0;
1571 }
1572 
1573 static int
ip_vs_receive(struct socket * sock,char * buffer,const size_t buflen)1574 ip_vs_receive(struct socket *sock, char *buffer, const size_t buflen)
1575 {
1576 	struct msghdr		msg = {NULL,};
1577 	struct kvec		iov;
1578 	int			len;
1579 
1580 	EnterFunction(7);
1581 
1582 	/* Receive a packet */
1583 	iov.iov_base     = buffer;
1584 	iov.iov_len      = (size_t)buflen;
1585 
1586 	len = kernel_recvmsg(sock, &msg, &iov, 1, buflen, MSG_DONTWAIT);
1587 
1588 	if (len < 0)
1589 		return len;
1590 
1591 	LeaveFunction(7);
1592 	return len;
1593 }
1594 
1595 /* Wakeup the master thread for sending */
master_wakeup_work_handler(struct work_struct * work)1596 static void master_wakeup_work_handler(struct work_struct *work)
1597 {
1598 	struct ipvs_master_sync_state *ms =
1599 		container_of(work, struct ipvs_master_sync_state,
1600 			     master_wakeup_work.work);
1601 	struct netns_ipvs *ipvs = ms->ipvs;
1602 
1603 	spin_lock_bh(&ipvs->sync_lock);
1604 	if (ms->sync_queue_len &&
1605 	    ms->sync_queue_delay < IPVS_SYNC_WAKEUP_RATE) {
1606 		ms->sync_queue_delay = IPVS_SYNC_WAKEUP_RATE;
1607 		wake_up_process(ms->master_thread);
1608 	}
1609 	spin_unlock_bh(&ipvs->sync_lock);
1610 }
1611 
1612 /* Get next buffer to send */
1613 static inline struct ip_vs_sync_buff *
next_sync_buff(struct netns_ipvs * ipvs,struct ipvs_master_sync_state * ms)1614 next_sync_buff(struct netns_ipvs *ipvs, struct ipvs_master_sync_state *ms)
1615 {
1616 	struct ip_vs_sync_buff *sb;
1617 
1618 	sb = sb_dequeue(ipvs, ms);
1619 	if (sb)
1620 		return sb;
1621 	/* Do not delay entries in buffer for more than 2 seconds */
1622 	return get_curr_sync_buff(ipvs, ms, IPVS_SYNC_FLUSH_TIME);
1623 }
1624 
sync_thread_master(void * data)1625 static int sync_thread_master(void *data)
1626 {
1627 	struct ip_vs_sync_thread_data *tinfo = data;
1628 	struct netns_ipvs *ipvs = net_ipvs(tinfo->net);
1629 	struct ipvs_master_sync_state *ms = &ipvs->ms[tinfo->id];
1630 	struct sock *sk = tinfo->sock->sk;
1631 	struct ip_vs_sync_buff *sb;
1632 
1633 	pr_info("sync thread started: state = MASTER, mcast_ifn = %s, "
1634 		"syncid = %d, id = %d\n",
1635 		ipvs->master_mcast_ifn, ipvs->master_syncid, tinfo->id);
1636 
1637 	for (;;) {
1638 		sb = next_sync_buff(ipvs, ms);
1639 		if (unlikely(kthread_should_stop()))
1640 			break;
1641 		if (!sb) {
1642 			schedule_timeout(IPVS_SYNC_CHECK_PERIOD);
1643 			continue;
1644 		}
1645 		while (ip_vs_send_sync_msg(tinfo->sock, sb->mesg) < 0) {
1646 			/* (Ab)use interruptible sleep to avoid increasing
1647 			 * the load avg.
1648 			 */
1649 			__wait_event_interruptible(*sk_sleep(sk),
1650 						   sock_writeable(sk) ||
1651 						   kthread_should_stop());
1652 			if (unlikely(kthread_should_stop()))
1653 				goto done;
1654 		}
1655 		ip_vs_sync_buff_release(sb);
1656 	}
1657 
1658 done:
1659 	__set_current_state(TASK_RUNNING);
1660 	if (sb)
1661 		ip_vs_sync_buff_release(sb);
1662 
1663 	/* clean up the sync_buff queue */
1664 	while ((sb = sb_dequeue(ipvs, ms)))
1665 		ip_vs_sync_buff_release(sb);
1666 	__set_current_state(TASK_RUNNING);
1667 
1668 	/* clean up the current sync_buff */
1669 	sb = get_curr_sync_buff(ipvs, ms, 0);
1670 	if (sb)
1671 		ip_vs_sync_buff_release(sb);
1672 
1673 	/* release the sending multicast socket */
1674 	sk_release_kernel(tinfo->sock->sk);
1675 	kfree(tinfo);
1676 
1677 	return 0;
1678 }
1679 
1680 
sync_thread_backup(void * data)1681 static int sync_thread_backup(void *data)
1682 {
1683 	struct ip_vs_sync_thread_data *tinfo = data;
1684 	struct netns_ipvs *ipvs = net_ipvs(tinfo->net);
1685 	int len;
1686 
1687 	pr_info("sync thread started: state = BACKUP, mcast_ifn = %s, "
1688 		"syncid = %d, id = %d\n",
1689 		ipvs->backup_mcast_ifn, ipvs->backup_syncid, tinfo->id);
1690 
1691 	while (!kthread_should_stop()) {
1692 		wait_event_interruptible(*sk_sleep(tinfo->sock->sk),
1693 			 !skb_queue_empty(&tinfo->sock->sk->sk_receive_queue)
1694 			 || kthread_should_stop());
1695 
1696 		/* do we have data now? */
1697 		while (!skb_queue_empty(&(tinfo->sock->sk->sk_receive_queue))) {
1698 			len = ip_vs_receive(tinfo->sock, tinfo->buf,
1699 					ipvs->recv_mesg_maxlen);
1700 			if (len <= 0) {
1701 				if (len != -EAGAIN)
1702 					pr_err("receiving message error\n");
1703 				break;
1704 			}
1705 
1706 			ip_vs_process_message(tinfo->net, tinfo->buf, len);
1707 		}
1708 	}
1709 
1710 	/* release the sending multicast socket */
1711 	sk_release_kernel(tinfo->sock->sk);
1712 	kfree(tinfo->buf);
1713 	kfree(tinfo);
1714 
1715 	return 0;
1716 }
1717 
1718 
start_sync_thread(struct net * net,int state,char * mcast_ifn,__u8 syncid)1719 int start_sync_thread(struct net *net, int state, char *mcast_ifn, __u8 syncid)
1720 {
1721 	struct ip_vs_sync_thread_data *tinfo;
1722 	struct task_struct **array = NULL, *task;
1723 	struct socket *sock;
1724 	struct netns_ipvs *ipvs = net_ipvs(net);
1725 	char *name;
1726 	int (*threadfn)(void *data);
1727 	int id, count;
1728 	int result = -ENOMEM;
1729 
1730 	IP_VS_DBG(7, "%s(): pid %d\n", __func__, task_pid_nr(current));
1731 	IP_VS_DBG(7, "Each ip_vs_sync_conn entry needs %Zd bytes\n",
1732 		  sizeof(struct ip_vs_sync_conn_v0));
1733 
1734 	if (!ipvs->sync_state) {
1735 		count = clamp(sysctl_sync_ports(ipvs), 1, IPVS_SYNC_PORTS_MAX);
1736 		ipvs->threads_mask = count - 1;
1737 	} else
1738 		count = ipvs->threads_mask + 1;
1739 
1740 	if (state == IP_VS_STATE_MASTER) {
1741 		if (ipvs->ms)
1742 			return -EEXIST;
1743 
1744 		strlcpy(ipvs->master_mcast_ifn, mcast_ifn,
1745 			sizeof(ipvs->master_mcast_ifn));
1746 		ipvs->master_syncid = syncid;
1747 		name = "ipvs-m:%d:%d";
1748 		threadfn = sync_thread_master;
1749 	} else if (state == IP_VS_STATE_BACKUP) {
1750 		if (ipvs->backup_threads)
1751 			return -EEXIST;
1752 
1753 		strlcpy(ipvs->backup_mcast_ifn, mcast_ifn,
1754 			sizeof(ipvs->backup_mcast_ifn));
1755 		ipvs->backup_syncid = syncid;
1756 		name = "ipvs-b:%d:%d";
1757 		threadfn = sync_thread_backup;
1758 	} else {
1759 		return -EINVAL;
1760 	}
1761 
1762 	if (state == IP_VS_STATE_MASTER) {
1763 		struct ipvs_master_sync_state *ms;
1764 
1765 		ipvs->ms = kzalloc(count * sizeof(ipvs->ms[0]), GFP_KERNEL);
1766 		if (!ipvs->ms)
1767 			goto out;
1768 		ms = ipvs->ms;
1769 		for (id = 0; id < count; id++, ms++) {
1770 			INIT_LIST_HEAD(&ms->sync_queue);
1771 			ms->sync_queue_len = 0;
1772 			ms->sync_queue_delay = 0;
1773 			INIT_DELAYED_WORK(&ms->master_wakeup_work,
1774 					  master_wakeup_work_handler);
1775 			ms->ipvs = ipvs;
1776 		}
1777 	} else {
1778 		array = kzalloc(count * sizeof(struct task_struct *),
1779 				GFP_KERNEL);
1780 		if (!array)
1781 			goto out;
1782 	}
1783 	set_sync_mesg_maxlen(net, state);
1784 
1785 	tinfo = NULL;
1786 	for (id = 0; id < count; id++) {
1787 		if (state == IP_VS_STATE_MASTER)
1788 			sock = make_send_sock(net, id);
1789 		else
1790 			sock = make_receive_sock(net, id);
1791 		if (IS_ERR(sock)) {
1792 			result = PTR_ERR(sock);
1793 			goto outtinfo;
1794 		}
1795 		tinfo = kmalloc(sizeof(*tinfo), GFP_KERNEL);
1796 		if (!tinfo)
1797 			goto outsocket;
1798 		tinfo->net = net;
1799 		tinfo->sock = sock;
1800 		if (state == IP_VS_STATE_BACKUP) {
1801 			tinfo->buf = kmalloc(ipvs->recv_mesg_maxlen,
1802 					     GFP_KERNEL);
1803 			if (!tinfo->buf)
1804 				goto outtinfo;
1805 		} else {
1806 			tinfo->buf = NULL;
1807 		}
1808 		tinfo->id = id;
1809 
1810 		task = kthread_run(threadfn, tinfo, name, ipvs->gen, id);
1811 		if (IS_ERR(task)) {
1812 			result = PTR_ERR(task);
1813 			goto outtinfo;
1814 		}
1815 		tinfo = NULL;
1816 		if (state == IP_VS_STATE_MASTER)
1817 			ipvs->ms[id].master_thread = task;
1818 		else
1819 			array[id] = task;
1820 	}
1821 
1822 	/* mark as active */
1823 
1824 	if (state == IP_VS_STATE_BACKUP)
1825 		ipvs->backup_threads = array;
1826 	spin_lock_bh(&ipvs->sync_buff_lock);
1827 	ipvs->sync_state |= state;
1828 	spin_unlock_bh(&ipvs->sync_buff_lock);
1829 
1830 	/* increase the module use count */
1831 	ip_vs_use_count_inc();
1832 
1833 	return 0;
1834 
1835 outsocket:
1836 	sk_release_kernel(sock->sk);
1837 
1838 outtinfo:
1839 	if (tinfo) {
1840 		sk_release_kernel(tinfo->sock->sk);
1841 		kfree(tinfo->buf);
1842 		kfree(tinfo);
1843 	}
1844 	count = id;
1845 	while (count-- > 0) {
1846 		if (state == IP_VS_STATE_MASTER)
1847 			kthread_stop(ipvs->ms[count].master_thread);
1848 		else
1849 			kthread_stop(array[count]);
1850 	}
1851 	kfree(array);
1852 
1853 out:
1854 	if (!(ipvs->sync_state & IP_VS_STATE_MASTER)) {
1855 		kfree(ipvs->ms);
1856 		ipvs->ms = NULL;
1857 	}
1858 	return result;
1859 }
1860 
1861 
stop_sync_thread(struct net * net,int state)1862 int stop_sync_thread(struct net *net, int state)
1863 {
1864 	struct netns_ipvs *ipvs = net_ipvs(net);
1865 	struct task_struct **array;
1866 	int id;
1867 	int retc = -EINVAL;
1868 
1869 	IP_VS_DBG(7, "%s(): pid %d\n", __func__, task_pid_nr(current));
1870 
1871 	if (state == IP_VS_STATE_MASTER) {
1872 		if (!ipvs->ms)
1873 			return -ESRCH;
1874 
1875 		/*
1876 		 * The lock synchronizes with sb_queue_tail(), so that we don't
1877 		 * add sync buffers to the queue, when we are already in
1878 		 * progress of stopping the master sync daemon.
1879 		 */
1880 
1881 		spin_lock_bh(&ipvs->sync_buff_lock);
1882 		spin_lock(&ipvs->sync_lock);
1883 		ipvs->sync_state &= ~IP_VS_STATE_MASTER;
1884 		spin_unlock(&ipvs->sync_lock);
1885 		spin_unlock_bh(&ipvs->sync_buff_lock);
1886 
1887 		retc = 0;
1888 		for (id = ipvs->threads_mask; id >= 0; id--) {
1889 			struct ipvs_master_sync_state *ms = &ipvs->ms[id];
1890 			int ret;
1891 
1892 			pr_info("stopping master sync thread %d ...\n",
1893 				task_pid_nr(ms->master_thread));
1894 			cancel_delayed_work_sync(&ms->master_wakeup_work);
1895 			ret = kthread_stop(ms->master_thread);
1896 			if (retc >= 0)
1897 				retc = ret;
1898 		}
1899 		kfree(ipvs->ms);
1900 		ipvs->ms = NULL;
1901 	} else if (state == IP_VS_STATE_BACKUP) {
1902 		if (!ipvs->backup_threads)
1903 			return -ESRCH;
1904 
1905 		ipvs->sync_state &= ~IP_VS_STATE_BACKUP;
1906 		array = ipvs->backup_threads;
1907 		retc = 0;
1908 		for (id = ipvs->threads_mask; id >= 0; id--) {
1909 			int ret;
1910 
1911 			pr_info("stopping backup sync thread %d ...\n",
1912 				task_pid_nr(array[id]));
1913 			ret = kthread_stop(array[id]);
1914 			if (retc >= 0)
1915 				retc = ret;
1916 		}
1917 		kfree(array);
1918 		ipvs->backup_threads = NULL;
1919 	}
1920 
1921 	/* decrease the module use count */
1922 	ip_vs_use_count_dec();
1923 
1924 	return retc;
1925 }
1926 
1927 /*
1928  * Initialize data struct for each netns
1929  */
ip_vs_sync_net_init(struct net * net)1930 int __net_init ip_vs_sync_net_init(struct net *net)
1931 {
1932 	struct netns_ipvs *ipvs = net_ipvs(net);
1933 
1934 	__mutex_init(&ipvs->sync_mutex, "ipvs->sync_mutex", &__ipvs_sync_key);
1935 	spin_lock_init(&ipvs->sync_lock);
1936 	spin_lock_init(&ipvs->sync_buff_lock);
1937 	return 0;
1938 }
1939 
ip_vs_sync_net_cleanup(struct net * net)1940 void ip_vs_sync_net_cleanup(struct net *net)
1941 {
1942 	int retc;
1943 	struct netns_ipvs *ipvs = net_ipvs(net);
1944 
1945 	mutex_lock(&ipvs->sync_mutex);
1946 	retc = stop_sync_thread(net, IP_VS_STATE_MASTER);
1947 	if (retc && retc != -ESRCH)
1948 		pr_err("Failed to stop Master Daemon\n");
1949 
1950 	retc = stop_sync_thread(net, IP_VS_STATE_BACKUP);
1951 	if (retc && retc != -ESRCH)
1952 		pr_err("Failed to stop Backup Daemon\n");
1953 	mutex_unlock(&ipvs->sync_mutex);
1954 }
1955