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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 conn should be synced.
429  * pkts: conn packets, use sysctl_sync_threshold to avoid packet check
430  * - (1) sync_refresh_period: reduce sync rate. Additionally, retry
431  *	sync_retries times with period of sync_refresh_period/8
432  * - (2) if both sync_refresh_period and sync_period are 0 send sync only
433  *	for state changes or only once when pkts matches sync_threshold
434  * - (3) templates: rate can be reduced only with sync_refresh_period or
435  *	with (2)
436  */
ip_vs_sync_conn_needed(struct netns_ipvs * ipvs,struct ip_vs_conn * cp,int pkts)437 static int ip_vs_sync_conn_needed(struct netns_ipvs *ipvs,
438 				  struct ip_vs_conn *cp, int pkts)
439 {
440 	unsigned long orig = ACCESS_ONCE(cp->sync_endtime);
441 	unsigned long now = jiffies;
442 	unsigned long n = (now + cp->timeout) & ~3UL;
443 	unsigned int sync_refresh_period;
444 	int sync_period;
445 	int force;
446 
447 	/* Check if we sync in current state */
448 	if (unlikely(cp->flags & IP_VS_CONN_F_TEMPLATE))
449 		force = 0;
450 	else if (likely(cp->protocol == IPPROTO_TCP)) {
451 		if (!((1 << cp->state) &
452 		      ((1 << IP_VS_TCP_S_ESTABLISHED) |
453 		       (1 << IP_VS_TCP_S_FIN_WAIT) |
454 		       (1 << IP_VS_TCP_S_CLOSE) |
455 		       (1 << IP_VS_TCP_S_CLOSE_WAIT) |
456 		       (1 << IP_VS_TCP_S_TIME_WAIT))))
457 			return 0;
458 		force = cp->state != cp->old_state;
459 		if (force && cp->state != IP_VS_TCP_S_ESTABLISHED)
460 			goto set;
461 	} else if (unlikely(cp->protocol == IPPROTO_SCTP)) {
462 		if (!((1 << cp->state) &
463 		      ((1 << IP_VS_SCTP_S_ESTABLISHED) |
464 		       (1 << IP_VS_SCTP_S_CLOSED) |
465 		       (1 << IP_VS_SCTP_S_SHUT_ACK_CLI) |
466 		       (1 << IP_VS_SCTP_S_SHUT_ACK_SER))))
467 			return 0;
468 		force = cp->state != cp->old_state;
469 		if (force && cp->state != IP_VS_SCTP_S_ESTABLISHED)
470 			goto set;
471 	} else {
472 		/* UDP or another protocol with single state */
473 		force = 0;
474 	}
475 
476 	sync_refresh_period = sysctl_sync_refresh_period(ipvs);
477 	if (sync_refresh_period > 0) {
478 		long diff = n - orig;
479 		long min_diff = max(cp->timeout >> 1, 10UL * HZ);
480 
481 		/* Avoid sync if difference is below sync_refresh_period
482 		 * and below the half timeout.
483 		 */
484 		if (abs(diff) < min_t(long, sync_refresh_period, min_diff)) {
485 			int retries = orig & 3;
486 
487 			if (retries >= sysctl_sync_retries(ipvs))
488 				return 0;
489 			if (time_before(now, orig - cp->timeout +
490 					(sync_refresh_period >> 3)))
491 				return 0;
492 			n |= retries + 1;
493 		}
494 	}
495 	sync_period = sysctl_sync_period(ipvs);
496 	if (sync_period > 0) {
497 		if (!(cp->flags & IP_VS_CONN_F_TEMPLATE) &&
498 		    pkts % sync_period != sysctl_sync_threshold(ipvs))
499 			return 0;
500 	} else if (sync_refresh_period <= 0 &&
501 		   pkts != sysctl_sync_threshold(ipvs))
502 		return 0;
503 
504 set:
505 	cp->old_state = cp->state;
506 	n = cmpxchg(&cp->sync_endtime, orig, n);
507 	return n == orig || force;
508 }
509 
510 /*
511  *      Version 0 , could be switched in by sys_ctl.
512  *      Add an ip_vs_conn information into the current sync_buff.
513  */
ip_vs_sync_conn_v0(struct net * net,struct ip_vs_conn * cp,int pkts)514 static void ip_vs_sync_conn_v0(struct net *net, struct ip_vs_conn *cp,
515 			       int pkts)
516 {
517 	struct netns_ipvs *ipvs = net_ipvs(net);
518 	struct ip_vs_sync_mesg_v0 *m;
519 	struct ip_vs_sync_conn_v0 *s;
520 	struct ip_vs_sync_buff *buff;
521 	struct ipvs_master_sync_state *ms;
522 	int id;
523 	int len;
524 
525 	if (unlikely(cp->af != AF_INET))
526 		return;
527 	/* Do not sync ONE PACKET */
528 	if (cp->flags & IP_VS_CONN_F_ONE_PACKET)
529 		return;
530 
531 	if (!ip_vs_sync_conn_needed(ipvs, cp, pkts))
532 		return;
533 
534 	spin_lock_bh(&ipvs->sync_buff_lock);
535 	if (!(ipvs->sync_state & IP_VS_STATE_MASTER)) {
536 		spin_unlock_bh(&ipvs->sync_buff_lock);
537 		return;
538 	}
539 
540 	id = select_master_thread_id(ipvs, cp);
541 	ms = &ipvs->ms[id];
542 	buff = ms->sync_buff;
543 	if (buff) {
544 		m = (struct ip_vs_sync_mesg_v0 *) buff->mesg;
545 		/* Send buffer if it is for v1 */
546 		if (!m->nr_conns) {
547 			sb_queue_tail(ipvs, ms);
548 			ms->sync_buff = NULL;
549 			buff = NULL;
550 		}
551 	}
552 	if (!buff) {
553 		buff = ip_vs_sync_buff_create_v0(ipvs);
554 		if (!buff) {
555 			spin_unlock_bh(&ipvs->sync_buff_lock);
556 			pr_err("ip_vs_sync_buff_create failed.\n");
557 			return;
558 		}
559 		ms->sync_buff = buff;
560 	}
561 
562 	len = (cp->flags & IP_VS_CONN_F_SEQ_MASK) ? FULL_CONN_SIZE :
563 		SIMPLE_CONN_SIZE;
564 	m = (struct ip_vs_sync_mesg_v0 *) buff->mesg;
565 	s = (struct ip_vs_sync_conn_v0 *) buff->head;
566 
567 	/* copy members */
568 	s->reserved = 0;
569 	s->protocol = cp->protocol;
570 	s->cport = cp->cport;
571 	s->vport = cp->vport;
572 	s->dport = cp->dport;
573 	s->caddr = cp->caddr.ip;
574 	s->vaddr = cp->vaddr.ip;
575 	s->daddr = cp->daddr.ip;
576 	s->flags = htons(cp->flags & ~IP_VS_CONN_F_HASHED);
577 	s->state = htons(cp->state);
578 	if (cp->flags & IP_VS_CONN_F_SEQ_MASK) {
579 		struct ip_vs_sync_conn_options *opt =
580 			(struct ip_vs_sync_conn_options *)&s[1];
581 		memcpy(opt, &cp->in_seq, sizeof(*opt));
582 	}
583 
584 	m->nr_conns++;
585 	m->size = htons(ntohs(m->size) + len);
586 	buff->head += len;
587 
588 	/* check if there is a space for next one */
589 	if (buff->head + FULL_CONN_SIZE > buff->end) {
590 		sb_queue_tail(ipvs, ms);
591 		ms->sync_buff = NULL;
592 	}
593 	spin_unlock_bh(&ipvs->sync_buff_lock);
594 
595 	/* synchronize its controller if it has */
596 	cp = cp->control;
597 	if (cp) {
598 		if (cp->flags & IP_VS_CONN_F_TEMPLATE)
599 			pkts = atomic_add_return(1, &cp->in_pkts);
600 		else
601 			pkts = sysctl_sync_threshold(ipvs);
602 		ip_vs_sync_conn(net, cp->control, pkts);
603 	}
604 }
605 
606 /*
607  *      Add an ip_vs_conn information into the current sync_buff.
608  *      Called by ip_vs_in.
609  *      Sending Version 1 messages
610  */
ip_vs_sync_conn(struct net * net,struct ip_vs_conn * cp,int pkts)611 void ip_vs_sync_conn(struct net *net, struct ip_vs_conn *cp, int pkts)
612 {
613 	struct netns_ipvs *ipvs = net_ipvs(net);
614 	struct ip_vs_sync_mesg *m;
615 	union ip_vs_sync_conn *s;
616 	struct ip_vs_sync_buff *buff;
617 	struct ipvs_master_sync_state *ms;
618 	int id;
619 	__u8 *p;
620 	unsigned int len, pe_name_len, pad;
621 
622 	/* Handle old version of the protocol */
623 	if (sysctl_sync_ver(ipvs) == 0) {
624 		ip_vs_sync_conn_v0(net, cp, pkts);
625 		return;
626 	}
627 	/* Do not sync ONE PACKET */
628 	if (cp->flags & IP_VS_CONN_F_ONE_PACKET)
629 		goto control;
630 sloop:
631 	if (!ip_vs_sync_conn_needed(ipvs, cp, pkts))
632 		goto control;
633 
634 	/* Sanity checks */
635 	pe_name_len = 0;
636 	if (cp->pe_data_len) {
637 		if (!cp->pe_data || !cp->dest) {
638 			IP_VS_ERR_RL("SYNC, connection pe_data invalid\n");
639 			return;
640 		}
641 		pe_name_len = strnlen(cp->pe->name, IP_VS_PENAME_MAXLEN);
642 	}
643 
644 	spin_lock_bh(&ipvs->sync_buff_lock);
645 	if (!(ipvs->sync_state & IP_VS_STATE_MASTER)) {
646 		spin_unlock_bh(&ipvs->sync_buff_lock);
647 		return;
648 	}
649 
650 	id = select_master_thread_id(ipvs, cp);
651 	ms = &ipvs->ms[id];
652 
653 #ifdef CONFIG_IP_VS_IPV6
654 	if (cp->af == AF_INET6)
655 		len = sizeof(struct ip_vs_sync_v6);
656 	else
657 #endif
658 		len = sizeof(struct ip_vs_sync_v4);
659 
660 	if (cp->flags & IP_VS_CONN_F_SEQ_MASK)
661 		len += sizeof(struct ip_vs_sync_conn_options) + 2;
662 
663 	if (cp->pe_data_len)
664 		len += cp->pe_data_len + 2;	/* + Param hdr field */
665 	if (pe_name_len)
666 		len += pe_name_len + 2;
667 
668 	/* check if there is a space for this one  */
669 	pad = 0;
670 	buff = ms->sync_buff;
671 	if (buff) {
672 		m = buff->mesg;
673 		pad = (4 - (size_t) buff->head) & 3;
674 		/* Send buffer if it is for v0 */
675 		if (buff->head + len + pad > buff->end || m->reserved) {
676 			sb_queue_tail(ipvs, ms);
677 			ms->sync_buff = NULL;
678 			buff = NULL;
679 			pad = 0;
680 		}
681 	}
682 
683 	if (!buff) {
684 		buff = ip_vs_sync_buff_create(ipvs);
685 		if (!buff) {
686 			spin_unlock_bh(&ipvs->sync_buff_lock);
687 			pr_err("ip_vs_sync_buff_create failed.\n");
688 			return;
689 		}
690 		ms->sync_buff = buff;
691 		m = buff->mesg;
692 	}
693 
694 	p = buff->head;
695 	buff->head += pad + len;
696 	m->size = htons(ntohs(m->size) + pad + len);
697 	/* Add ev. padding from prev. sync_conn */
698 	while (pad--)
699 		*(p++) = 0;
700 
701 	s = (union ip_vs_sync_conn *)p;
702 
703 	/* Set message type  & copy members */
704 	s->v4.type = (cp->af == AF_INET6 ? STYPE_F_INET6 : 0);
705 	s->v4.ver_size = htons(len & SVER_MASK);	/* Version 0 */
706 	s->v4.flags = htonl(cp->flags & ~IP_VS_CONN_F_HASHED);
707 	s->v4.state = htons(cp->state);
708 	s->v4.protocol = cp->protocol;
709 	s->v4.cport = cp->cport;
710 	s->v4.vport = cp->vport;
711 	s->v4.dport = cp->dport;
712 	s->v4.fwmark = htonl(cp->fwmark);
713 	s->v4.timeout = htonl(cp->timeout / HZ);
714 	m->nr_conns++;
715 
716 #ifdef CONFIG_IP_VS_IPV6
717 	if (cp->af == AF_INET6) {
718 		p += sizeof(struct ip_vs_sync_v6);
719 		s->v6.caddr = cp->caddr.in6;
720 		s->v6.vaddr = cp->vaddr.in6;
721 		s->v6.daddr = cp->daddr.in6;
722 	} else
723 #endif
724 	{
725 		p += sizeof(struct ip_vs_sync_v4);	/* options ptr */
726 		s->v4.caddr = cp->caddr.ip;
727 		s->v4.vaddr = cp->vaddr.ip;
728 		s->v4.daddr = cp->daddr.ip;
729 	}
730 	if (cp->flags & IP_VS_CONN_F_SEQ_MASK) {
731 		*(p++) = IPVS_OPT_SEQ_DATA;
732 		*(p++) = sizeof(struct ip_vs_sync_conn_options);
733 		hton_seq((struct ip_vs_seq *)p, &cp->in_seq);
734 		p += sizeof(struct ip_vs_seq);
735 		hton_seq((struct ip_vs_seq *)p, &cp->out_seq);
736 		p += sizeof(struct ip_vs_seq);
737 	}
738 	/* Handle pe data */
739 	if (cp->pe_data_len && cp->pe_data) {
740 		*(p++) = IPVS_OPT_PE_DATA;
741 		*(p++) = cp->pe_data_len;
742 		memcpy(p, cp->pe_data, cp->pe_data_len);
743 		p += cp->pe_data_len;
744 		if (pe_name_len) {
745 			/* Add PE_NAME */
746 			*(p++) = IPVS_OPT_PE_NAME;
747 			*(p++) = pe_name_len;
748 			memcpy(p, cp->pe->name, pe_name_len);
749 			p += pe_name_len;
750 		}
751 	}
752 
753 	spin_unlock_bh(&ipvs->sync_buff_lock);
754 
755 control:
756 	/* synchronize its controller if it has */
757 	cp = cp->control;
758 	if (!cp)
759 		return;
760 	if (cp->flags & IP_VS_CONN_F_TEMPLATE)
761 		pkts = atomic_add_return(1, &cp->in_pkts);
762 	else
763 		pkts = sysctl_sync_threshold(ipvs);
764 	goto sloop;
765 }
766 
767 /*
768  *  fill_param used by version 1
769  */
770 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)771 ip_vs_conn_fill_param_sync(struct net *net, int af, union ip_vs_sync_conn *sc,
772 			   struct ip_vs_conn_param *p,
773 			   __u8 *pe_data, unsigned int pe_data_len,
774 			   __u8 *pe_name, unsigned int pe_name_len)
775 {
776 #ifdef CONFIG_IP_VS_IPV6
777 	if (af == AF_INET6)
778 		ip_vs_conn_fill_param(net, af, sc->v6.protocol,
779 				      (const union nf_inet_addr *)&sc->v6.caddr,
780 				      sc->v6.cport,
781 				      (const union nf_inet_addr *)&sc->v6.vaddr,
782 				      sc->v6.vport, p);
783 	else
784 #endif
785 		ip_vs_conn_fill_param(net, af, sc->v4.protocol,
786 				      (const union nf_inet_addr *)&sc->v4.caddr,
787 				      sc->v4.cport,
788 				      (const union nf_inet_addr *)&sc->v4.vaddr,
789 				      sc->v4.vport, p);
790 	/* Handle pe data */
791 	if (pe_data_len) {
792 		if (pe_name_len) {
793 			char buff[IP_VS_PENAME_MAXLEN+1];
794 
795 			memcpy(buff, pe_name, pe_name_len);
796 			buff[pe_name_len]=0;
797 			p->pe = __ip_vs_pe_getbyname(buff);
798 			if (!p->pe) {
799 				IP_VS_DBG(3, "BACKUP, no %s engine found/loaded\n",
800 					     buff);
801 				return 1;
802 			}
803 		} else {
804 			IP_VS_ERR_RL("BACKUP, Invalid PE parameters\n");
805 			return 1;
806 		}
807 
808 		p->pe_data = kmemdup(pe_data, pe_data_len, GFP_ATOMIC);
809 		if (!p->pe_data) {
810 			if (p->pe->module)
811 				module_put(p->pe->module);
812 			return -ENOMEM;
813 		}
814 		p->pe_data_len = pe_data_len;
815 	}
816 	return 0;
817 }
818 
819 /*
820  *  Connection Add / Update.
821  *  Common for version 0 and 1 reception of backup sync_conns.
822  *  Param: ...
823  *         timeout is in sec.
824  */
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)825 static void ip_vs_proc_conn(struct net *net, struct ip_vs_conn_param *param,
826 			    unsigned int flags, unsigned int state,
827 			    unsigned int protocol, unsigned int type,
828 			    const union nf_inet_addr *daddr, __be16 dport,
829 			    unsigned long timeout, __u32 fwmark,
830 			    struct ip_vs_sync_conn_options *opt)
831 {
832 	struct ip_vs_dest *dest;
833 	struct ip_vs_conn *cp;
834 	struct netns_ipvs *ipvs = net_ipvs(net);
835 
836 	if (!(flags & IP_VS_CONN_F_TEMPLATE))
837 		cp = ip_vs_conn_in_get(param);
838 	else
839 		cp = ip_vs_ct_in_get(param);
840 
841 	if (cp) {
842 		/* Free pe_data */
843 		kfree(param->pe_data);
844 
845 		dest = cp->dest;
846 		spin_lock_bh(&cp->lock);
847 		if ((cp->flags ^ flags) & IP_VS_CONN_F_INACTIVE &&
848 		    !(flags & IP_VS_CONN_F_TEMPLATE) && dest) {
849 			if (flags & IP_VS_CONN_F_INACTIVE) {
850 				atomic_dec(&dest->activeconns);
851 				atomic_inc(&dest->inactconns);
852 			} else {
853 				atomic_inc(&dest->activeconns);
854 				atomic_dec(&dest->inactconns);
855 			}
856 		}
857 		flags &= IP_VS_CONN_F_BACKUP_UPD_MASK;
858 		flags |= cp->flags & ~IP_VS_CONN_F_BACKUP_UPD_MASK;
859 		cp->flags = flags;
860 		spin_unlock_bh(&cp->lock);
861 		if (!dest)
862 			ip_vs_try_bind_dest(cp);
863 	} else {
864 		/*
865 		 * Find the appropriate destination for the connection.
866 		 * If it is not found the connection will remain unbound
867 		 * but still handled.
868 		 */
869 		rcu_read_lock();
870 		dest = ip_vs_find_dest(net, type, daddr, dport, param->vaddr,
871 				       param->vport, protocol, fwmark, flags);
872 
873 		cp = ip_vs_conn_new(param, daddr, dport, flags, dest, fwmark);
874 		rcu_read_unlock();
875 		if (!cp) {
876 			if (param->pe_data)
877 				kfree(param->pe_data);
878 			IP_VS_DBG(2, "BACKUP, add new conn. failed\n");
879 			return;
880 		}
881 	}
882 
883 	if (opt)
884 		memcpy(&cp->in_seq, opt, sizeof(*opt));
885 	atomic_set(&cp->in_pkts, sysctl_sync_threshold(ipvs));
886 	cp->state = state;
887 	cp->old_state = cp->state;
888 	/*
889 	 * For Ver 0 messages style
890 	 *  - Not possible to recover the right timeout for templates
891 	 *  - can not find the right fwmark
892 	 *    virtual service. If needed, we can do it for
893 	 *    non-fwmark persistent services.
894 	 * Ver 1 messages style.
895 	 *  - No problem.
896 	 */
897 	if (timeout) {
898 		if (timeout > MAX_SCHEDULE_TIMEOUT / HZ)
899 			timeout = MAX_SCHEDULE_TIMEOUT / HZ;
900 		cp->timeout = timeout*HZ;
901 	} else {
902 		struct ip_vs_proto_data *pd;
903 
904 		pd = ip_vs_proto_data_get(net, protocol);
905 		if (!(flags & IP_VS_CONN_F_TEMPLATE) && pd && pd->timeout_table)
906 			cp->timeout = pd->timeout_table[state];
907 		else
908 			cp->timeout = (3*60*HZ);
909 	}
910 	ip_vs_conn_put(cp);
911 }
912 
913 /*
914  *  Process received multicast message for Version 0
915  */
ip_vs_process_message_v0(struct net * net,const char * buffer,const size_t buflen)916 static void ip_vs_process_message_v0(struct net *net, const char *buffer,
917 				     const size_t buflen)
918 {
919 	struct ip_vs_sync_mesg_v0 *m = (struct ip_vs_sync_mesg_v0 *)buffer;
920 	struct ip_vs_sync_conn_v0 *s;
921 	struct ip_vs_sync_conn_options *opt;
922 	struct ip_vs_protocol *pp;
923 	struct ip_vs_conn_param param;
924 	char *p;
925 	int i;
926 
927 	p = (char *)buffer + sizeof(struct ip_vs_sync_mesg_v0);
928 	for (i=0; i<m->nr_conns; i++) {
929 		unsigned int flags, state;
930 
931 		if (p + SIMPLE_CONN_SIZE > buffer+buflen) {
932 			IP_VS_ERR_RL("BACKUP v0, bogus conn\n");
933 			return;
934 		}
935 		s = (struct ip_vs_sync_conn_v0 *) p;
936 		flags = ntohs(s->flags) | IP_VS_CONN_F_SYNC;
937 		flags &= ~IP_VS_CONN_F_HASHED;
938 		if (flags & IP_VS_CONN_F_SEQ_MASK) {
939 			opt = (struct ip_vs_sync_conn_options *)&s[1];
940 			p += FULL_CONN_SIZE;
941 			if (p > buffer+buflen) {
942 				IP_VS_ERR_RL("BACKUP v0, Dropping buffer bogus conn options\n");
943 				return;
944 			}
945 		} else {
946 			opt = NULL;
947 			p += SIMPLE_CONN_SIZE;
948 		}
949 
950 		state = ntohs(s->state);
951 		if (!(flags & IP_VS_CONN_F_TEMPLATE)) {
952 			pp = ip_vs_proto_get(s->protocol);
953 			if (!pp) {
954 				IP_VS_DBG(2, "BACKUP v0, Unsupported protocol %u\n",
955 					s->protocol);
956 				continue;
957 			}
958 			if (state >= pp->num_states) {
959 				IP_VS_DBG(2, "BACKUP v0, Invalid %s state %u\n",
960 					pp->name, state);
961 				continue;
962 			}
963 		} else {
964 			/* protocol in templates is not used for state/timeout */
965 			if (state > 0) {
966 				IP_VS_DBG(2, "BACKUP v0, Invalid template state %u\n",
967 					state);
968 				state = 0;
969 			}
970 		}
971 
972 		ip_vs_conn_fill_param(net, AF_INET, s->protocol,
973 				      (const union nf_inet_addr *)&s->caddr,
974 				      s->cport,
975 				      (const union nf_inet_addr *)&s->vaddr,
976 				      s->vport, &param);
977 
978 		/* Send timeout as Zero */
979 		ip_vs_proc_conn(net, &param, flags, state, s->protocol, AF_INET,
980 				(union nf_inet_addr *)&s->daddr, s->dport,
981 				0, 0, opt);
982 	}
983 }
984 
985 /*
986  * Handle options
987  */
ip_vs_proc_seqopt(__u8 * p,unsigned int plen,__u32 * opt_flags,struct ip_vs_sync_conn_options * opt)988 static inline int ip_vs_proc_seqopt(__u8 *p, unsigned int plen,
989 				    __u32 *opt_flags,
990 				    struct ip_vs_sync_conn_options *opt)
991 {
992 	struct ip_vs_sync_conn_options *topt;
993 
994 	topt = (struct ip_vs_sync_conn_options *)p;
995 
996 	if (plen != sizeof(struct ip_vs_sync_conn_options)) {
997 		IP_VS_DBG(2, "BACKUP, bogus conn options length\n");
998 		return -EINVAL;
999 	}
1000 	if (*opt_flags & IPVS_OPT_F_SEQ_DATA) {
1001 		IP_VS_DBG(2, "BACKUP, conn options found twice\n");
1002 		return -EINVAL;
1003 	}
1004 	ntoh_seq(&topt->in_seq, &opt->in_seq);
1005 	ntoh_seq(&topt->out_seq, &opt->out_seq);
1006 	*opt_flags |= IPVS_OPT_F_SEQ_DATA;
1007 	return 0;
1008 }
1009 
ip_vs_proc_str(__u8 * p,unsigned int plen,unsigned int * data_len,__u8 ** data,unsigned int maxlen,__u32 * opt_flags,__u32 flag)1010 static int ip_vs_proc_str(__u8 *p, unsigned int plen, unsigned int *data_len,
1011 			  __u8 **data, unsigned int maxlen,
1012 			  __u32 *opt_flags, __u32 flag)
1013 {
1014 	if (plen > maxlen) {
1015 		IP_VS_DBG(2, "BACKUP, bogus par.data len > %d\n", maxlen);
1016 		return -EINVAL;
1017 	}
1018 	if (*opt_flags & flag) {
1019 		IP_VS_DBG(2, "BACKUP, Par.data found twice 0x%x\n", flag);
1020 		return -EINVAL;
1021 	}
1022 	*data_len = plen;
1023 	*data = p;
1024 	*opt_flags |= flag;
1025 	return 0;
1026 }
1027 /*
1028  *   Process a Version 1 sync. connection
1029  */
ip_vs_proc_sync_conn(struct net * net,__u8 * p,__u8 * msg_end)1030 static inline int ip_vs_proc_sync_conn(struct net *net, __u8 *p, __u8 *msg_end)
1031 {
1032 	struct ip_vs_sync_conn_options opt;
1033 	union  ip_vs_sync_conn *s;
1034 	struct ip_vs_protocol *pp;
1035 	struct ip_vs_conn_param param;
1036 	__u32 flags;
1037 	unsigned int af, state, pe_data_len=0, pe_name_len=0;
1038 	__u8 *pe_data=NULL, *pe_name=NULL;
1039 	__u32 opt_flags=0;
1040 	int retc=0;
1041 
1042 	s = (union ip_vs_sync_conn *) p;
1043 
1044 	if (s->v6.type & STYPE_F_INET6) {
1045 #ifdef CONFIG_IP_VS_IPV6
1046 		af = AF_INET6;
1047 		p += sizeof(struct ip_vs_sync_v6);
1048 #else
1049 		IP_VS_DBG(3,"BACKUP, IPv6 msg received, and IPVS is not compiled for IPv6\n");
1050 		retc = 10;
1051 		goto out;
1052 #endif
1053 	} else if (!s->v4.type) {
1054 		af = AF_INET;
1055 		p += sizeof(struct ip_vs_sync_v4);
1056 	} else {
1057 		return -10;
1058 	}
1059 	if (p > msg_end)
1060 		return -20;
1061 
1062 	/* Process optional params check Type & Len. */
1063 	while (p < msg_end) {
1064 		int ptype;
1065 		int plen;
1066 
1067 		if (p+2 > msg_end)
1068 			return -30;
1069 		ptype = *(p++);
1070 		plen  = *(p++);
1071 
1072 		if (!plen || ((p + plen) > msg_end))
1073 			return -40;
1074 		/* Handle seq option  p = param data */
1075 		switch (ptype & ~IPVS_OPT_F_PARAM) {
1076 		case IPVS_OPT_SEQ_DATA:
1077 			if (ip_vs_proc_seqopt(p, plen, &opt_flags, &opt))
1078 				return -50;
1079 			break;
1080 
1081 		case IPVS_OPT_PE_DATA:
1082 			if (ip_vs_proc_str(p, plen, &pe_data_len, &pe_data,
1083 					   IP_VS_PEDATA_MAXLEN, &opt_flags,
1084 					   IPVS_OPT_F_PE_DATA))
1085 				return -60;
1086 			break;
1087 
1088 		case IPVS_OPT_PE_NAME:
1089 			if (ip_vs_proc_str(p, plen,&pe_name_len, &pe_name,
1090 					   IP_VS_PENAME_MAXLEN, &opt_flags,
1091 					   IPVS_OPT_F_PE_NAME))
1092 				return -70;
1093 			break;
1094 
1095 		default:
1096 			/* Param data mandatory ? */
1097 			if (!(ptype & IPVS_OPT_F_PARAM)) {
1098 				IP_VS_DBG(3, "BACKUP, Unknown mandatory param %d found\n",
1099 					  ptype & ~IPVS_OPT_F_PARAM);
1100 				retc = 20;
1101 				goto out;
1102 			}
1103 		}
1104 		p += plen;  /* Next option */
1105 	}
1106 
1107 	/* Get flags and Mask off unsupported */
1108 	flags  = ntohl(s->v4.flags) & IP_VS_CONN_F_BACKUP_MASK;
1109 	flags |= IP_VS_CONN_F_SYNC;
1110 	state = ntohs(s->v4.state);
1111 
1112 	if (!(flags & IP_VS_CONN_F_TEMPLATE)) {
1113 		pp = ip_vs_proto_get(s->v4.protocol);
1114 		if (!pp) {
1115 			IP_VS_DBG(3,"BACKUP, Unsupported protocol %u\n",
1116 				s->v4.protocol);
1117 			retc = 30;
1118 			goto out;
1119 		}
1120 		if (state >= pp->num_states) {
1121 			IP_VS_DBG(3, "BACKUP, Invalid %s state %u\n",
1122 				pp->name, state);
1123 			retc = 40;
1124 			goto out;
1125 		}
1126 	} else {
1127 		/* protocol in templates is not used for state/timeout */
1128 		if (state > 0) {
1129 			IP_VS_DBG(3, "BACKUP, Invalid template state %u\n",
1130 				state);
1131 			state = 0;
1132 		}
1133 	}
1134 	if (ip_vs_conn_fill_param_sync(net, af, s, &param, pe_data,
1135 				       pe_data_len, pe_name, pe_name_len)) {
1136 		retc = 50;
1137 		goto out;
1138 	}
1139 	/* If only IPv4, just silent skip IPv6 */
1140 	if (af == AF_INET)
1141 		ip_vs_proc_conn(net, &param, flags, state, s->v4.protocol, af,
1142 				(union nf_inet_addr *)&s->v4.daddr, s->v4.dport,
1143 				ntohl(s->v4.timeout), ntohl(s->v4.fwmark),
1144 				(opt_flags & IPVS_OPT_F_SEQ_DATA ? &opt : NULL)
1145 				);
1146 #ifdef CONFIG_IP_VS_IPV6
1147 	else
1148 		ip_vs_proc_conn(net, &param, flags, state, s->v6.protocol, af,
1149 				(union nf_inet_addr *)&s->v6.daddr, s->v6.dport,
1150 				ntohl(s->v6.timeout), ntohl(s->v6.fwmark),
1151 				(opt_flags & IPVS_OPT_F_SEQ_DATA ? &opt : NULL)
1152 				);
1153 #endif
1154 	return 0;
1155 	/* Error exit */
1156 out:
1157 	IP_VS_DBG(2, "BACKUP, Single msg dropped err:%d\n", retc);
1158 	return retc;
1159 
1160 }
1161 /*
1162  *      Process received multicast message and create the corresponding
1163  *      ip_vs_conn entries.
1164  *      Handles Version 0 & 1
1165  */
ip_vs_process_message(struct net * net,__u8 * buffer,const size_t buflen)1166 static void ip_vs_process_message(struct net *net, __u8 *buffer,
1167 				  const size_t buflen)
1168 {
1169 	struct netns_ipvs *ipvs = net_ipvs(net);
1170 	struct ip_vs_sync_mesg *m2 = (struct ip_vs_sync_mesg *)buffer;
1171 	__u8 *p, *msg_end;
1172 	int i, nr_conns;
1173 
1174 	if (buflen < sizeof(struct ip_vs_sync_mesg_v0)) {
1175 		IP_VS_DBG(2, "BACKUP, message header too short\n");
1176 		return;
1177 	}
1178 
1179 	if (buflen != ntohs(m2->size)) {
1180 		IP_VS_DBG(2, "BACKUP, bogus message size\n");
1181 		return;
1182 	}
1183 	/* SyncID sanity check */
1184 	if (ipvs->backup_syncid != 0 && m2->syncid != ipvs->backup_syncid) {
1185 		IP_VS_DBG(7, "BACKUP, Ignoring syncid = %d\n", m2->syncid);
1186 		return;
1187 	}
1188 	/* Handle version 1  message */
1189 	if ((m2->version == SYNC_PROTO_VER) && (m2->reserved == 0)
1190 	    && (m2->spare == 0)) {
1191 
1192 		msg_end = buffer + sizeof(struct ip_vs_sync_mesg);
1193 		nr_conns = m2->nr_conns;
1194 
1195 		for (i=0; i<nr_conns; i++) {
1196 			union ip_vs_sync_conn *s;
1197 			unsigned int size;
1198 			int retc;
1199 
1200 			p = msg_end;
1201 			if (p + sizeof(s->v4) > buffer+buflen) {
1202 				IP_VS_ERR_RL("BACKUP, Dropping buffer, to small\n");
1203 				return;
1204 			}
1205 			s = (union ip_vs_sync_conn *)p;
1206 			size = ntohs(s->v4.ver_size) & SVER_MASK;
1207 			msg_end = p + size;
1208 			/* Basic sanity checks */
1209 			if (msg_end  > buffer+buflen) {
1210 				IP_VS_ERR_RL("BACKUP, Dropping buffer, msg > buffer\n");
1211 				return;
1212 			}
1213 			if (ntohs(s->v4.ver_size) >> SVER_SHIFT) {
1214 				IP_VS_ERR_RL("BACKUP, Dropping buffer, Unknown version %d\n",
1215 					      ntohs(s->v4.ver_size) >> SVER_SHIFT);
1216 				return;
1217 			}
1218 			/* Process a single sync_conn */
1219 			retc = ip_vs_proc_sync_conn(net, p, msg_end);
1220 			if (retc < 0) {
1221 				IP_VS_ERR_RL("BACKUP, Dropping buffer, Err: %d in decoding\n",
1222 					     retc);
1223 				return;
1224 			}
1225 			/* Make sure we have 32 bit alignment */
1226 			msg_end = p + ((size + 3) & ~3);
1227 		}
1228 	} else {
1229 		/* Old type of message */
1230 		ip_vs_process_message_v0(net, buffer, buflen);
1231 		return;
1232 	}
1233 }
1234 
1235 
1236 /*
1237  *      Setup sndbuf (mode=1) or rcvbuf (mode=0)
1238  */
set_sock_size(struct sock * sk,int mode,int val)1239 static void set_sock_size(struct sock *sk, int mode, int val)
1240 {
1241 	/* setsockopt(sock, SOL_SOCKET, SO_SNDBUF, &val, sizeof(val)); */
1242 	/* setsockopt(sock, SOL_SOCKET, SO_RCVBUF, &val, sizeof(val)); */
1243 	lock_sock(sk);
1244 	if (mode) {
1245 		val = clamp_t(int, val, (SOCK_MIN_SNDBUF + 1) / 2,
1246 			      sysctl_wmem_max);
1247 		sk->sk_sndbuf = val * 2;
1248 		sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
1249 	} else {
1250 		val = clamp_t(int, val, (SOCK_MIN_RCVBUF + 1) / 2,
1251 			      sysctl_rmem_max);
1252 		sk->sk_rcvbuf = val * 2;
1253 		sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
1254 	}
1255 	release_sock(sk);
1256 }
1257 
1258 /*
1259  *      Setup loopback of outgoing multicasts on a sending socket
1260  */
set_mcast_loop(struct sock * sk,u_char loop)1261 static void set_mcast_loop(struct sock *sk, u_char loop)
1262 {
1263 	struct inet_sock *inet = inet_sk(sk);
1264 
1265 	/* setsockopt(sock, SOL_IP, IP_MULTICAST_LOOP, &loop, sizeof(loop)); */
1266 	lock_sock(sk);
1267 	inet->mc_loop = loop ? 1 : 0;
1268 	release_sock(sk);
1269 }
1270 
1271 /*
1272  *      Specify TTL for outgoing multicasts on a sending socket
1273  */
set_mcast_ttl(struct sock * sk,u_char ttl)1274 static void set_mcast_ttl(struct sock *sk, u_char ttl)
1275 {
1276 	struct inet_sock *inet = inet_sk(sk);
1277 
1278 	/* setsockopt(sock, SOL_IP, IP_MULTICAST_TTL, &ttl, sizeof(ttl)); */
1279 	lock_sock(sk);
1280 	inet->mc_ttl = ttl;
1281 	release_sock(sk);
1282 }
1283 
1284 /*
1285  *      Specifiy default interface for outgoing multicasts
1286  */
set_mcast_if(struct sock * sk,char * ifname)1287 static int set_mcast_if(struct sock *sk, char *ifname)
1288 {
1289 	struct net_device *dev;
1290 	struct inet_sock *inet = inet_sk(sk);
1291 	struct net *net = sock_net(sk);
1292 
1293 	dev = __dev_get_by_name(net, ifname);
1294 	if (!dev)
1295 		return -ENODEV;
1296 
1297 	if (sk->sk_bound_dev_if && dev->ifindex != sk->sk_bound_dev_if)
1298 		return -EINVAL;
1299 
1300 	lock_sock(sk);
1301 	inet->mc_index = dev->ifindex;
1302 	/*  inet->mc_addr  = 0; */
1303 	release_sock(sk);
1304 
1305 	return 0;
1306 }
1307 
1308 
1309 /*
1310  *	Set the maximum length of sync message according to the
1311  *	specified interface's MTU.
1312  */
set_sync_mesg_maxlen(struct net * net,int sync_state)1313 static int set_sync_mesg_maxlen(struct net *net, int sync_state)
1314 {
1315 	struct netns_ipvs *ipvs = net_ipvs(net);
1316 	struct net_device *dev;
1317 	int num;
1318 
1319 	if (sync_state == IP_VS_STATE_MASTER) {
1320 		dev = __dev_get_by_name(net, ipvs->master_mcast_ifn);
1321 		if (!dev)
1322 			return -ENODEV;
1323 
1324 		num = (dev->mtu - sizeof(struct iphdr) -
1325 		       sizeof(struct udphdr) -
1326 		       SYNC_MESG_HEADER_LEN - 20) / SIMPLE_CONN_SIZE;
1327 		ipvs->send_mesg_maxlen = SYNC_MESG_HEADER_LEN +
1328 			SIMPLE_CONN_SIZE * min(num, MAX_CONNS_PER_SYNCBUFF);
1329 		IP_VS_DBG(7, "setting the maximum length of sync sending "
1330 			  "message %d.\n", ipvs->send_mesg_maxlen);
1331 	} else if (sync_state == IP_VS_STATE_BACKUP) {
1332 		dev = __dev_get_by_name(net, ipvs->backup_mcast_ifn);
1333 		if (!dev)
1334 			return -ENODEV;
1335 
1336 		ipvs->recv_mesg_maxlen = dev->mtu -
1337 			sizeof(struct iphdr) - sizeof(struct udphdr);
1338 		IP_VS_DBG(7, "setting the maximum length of sync receiving "
1339 			  "message %d.\n", ipvs->recv_mesg_maxlen);
1340 	}
1341 
1342 	return 0;
1343 }
1344 
1345 
1346 /*
1347  *      Join a multicast group.
1348  *      the group is specified by a class D multicast address 224.0.0.0/8
1349  *      in the in_addr structure passed in as a parameter.
1350  */
1351 static int
join_mcast_group(struct sock * sk,struct in_addr * addr,char * ifname)1352 join_mcast_group(struct sock *sk, struct in_addr *addr, char *ifname)
1353 {
1354 	struct net *net = sock_net(sk);
1355 	struct ip_mreqn mreq;
1356 	struct net_device *dev;
1357 	int ret;
1358 
1359 	memset(&mreq, 0, sizeof(mreq));
1360 	memcpy(&mreq.imr_multiaddr, addr, sizeof(struct in_addr));
1361 
1362 	dev = __dev_get_by_name(net, ifname);
1363 	if (!dev)
1364 		return -ENODEV;
1365 	if (sk->sk_bound_dev_if && dev->ifindex != sk->sk_bound_dev_if)
1366 		return -EINVAL;
1367 
1368 	mreq.imr_ifindex = dev->ifindex;
1369 
1370 	lock_sock(sk);
1371 	ret = ip_mc_join_group(sk, &mreq);
1372 	release_sock(sk);
1373 
1374 	return ret;
1375 }
1376 
1377 
bind_mcastif_addr(struct socket * sock,char * ifname)1378 static int bind_mcastif_addr(struct socket *sock, char *ifname)
1379 {
1380 	struct net *net = sock_net(sock->sk);
1381 	struct net_device *dev;
1382 	__be32 addr;
1383 	struct sockaddr_in sin;
1384 
1385 	dev = __dev_get_by_name(net, ifname);
1386 	if (!dev)
1387 		return -ENODEV;
1388 
1389 	addr = inet_select_addr(dev, 0, RT_SCOPE_UNIVERSE);
1390 	if (!addr)
1391 		pr_err("You probably need to specify IP address on "
1392 		       "multicast interface.\n");
1393 
1394 	IP_VS_DBG(7, "binding socket with (%s) %pI4\n",
1395 		  ifname, &addr);
1396 
1397 	/* Now bind the socket with the address of multicast interface */
1398 	sin.sin_family	     = AF_INET;
1399 	sin.sin_addr.s_addr  = addr;
1400 	sin.sin_port         = 0;
1401 
1402 	return sock->ops->bind(sock, (struct sockaddr*)&sin, sizeof(sin));
1403 }
1404 
1405 /*
1406  *      Set up sending multicast socket over UDP
1407  */
make_send_sock(struct net * net,int id)1408 static struct socket *make_send_sock(struct net *net, int id)
1409 {
1410 	struct netns_ipvs *ipvs = net_ipvs(net);
1411 	/* multicast addr */
1412 	struct sockaddr_in mcast_addr = {
1413 		.sin_family		= AF_INET,
1414 		.sin_port		= cpu_to_be16(IP_VS_SYNC_PORT + id),
1415 		.sin_addr.s_addr	= cpu_to_be32(IP_VS_SYNC_GROUP),
1416 	};
1417 	struct socket *sock;
1418 	int result;
1419 
1420 	/* First create a socket move it to right name space later */
1421 	result = sock_create_kern(PF_INET, SOCK_DGRAM, IPPROTO_UDP, &sock);
1422 	if (result < 0) {
1423 		pr_err("Error during creation of socket; terminating\n");
1424 		return ERR_PTR(result);
1425 	}
1426 	/*
1427 	 * Kernel sockets that are a part of a namespace, should not
1428 	 * hold a reference to a namespace in order to allow to stop it.
1429 	 * After sk_change_net should be released using sk_release_kernel.
1430 	 */
1431 	sk_change_net(sock->sk, net);
1432 	result = set_mcast_if(sock->sk, ipvs->master_mcast_ifn);
1433 	if (result < 0) {
1434 		pr_err("Error setting outbound mcast interface\n");
1435 		goto error;
1436 	}
1437 
1438 	set_mcast_loop(sock->sk, 0);
1439 	set_mcast_ttl(sock->sk, 1);
1440 	result = sysctl_sync_sock_size(ipvs);
1441 	if (result > 0)
1442 		set_sock_size(sock->sk, 1, result);
1443 
1444 	result = bind_mcastif_addr(sock, ipvs->master_mcast_ifn);
1445 	if (result < 0) {
1446 		pr_err("Error binding address of the mcast interface\n");
1447 		goto error;
1448 	}
1449 
1450 	result = sock->ops->connect(sock, (struct sockaddr *) &mcast_addr,
1451 			sizeof(struct sockaddr), 0);
1452 	if (result < 0) {
1453 		pr_err("Error connecting to the multicast addr\n");
1454 		goto error;
1455 	}
1456 
1457 	return sock;
1458 
1459 error:
1460 	sk_release_kernel(sock->sk);
1461 	return ERR_PTR(result);
1462 }
1463 
1464 
1465 /*
1466  *      Set up receiving multicast socket over UDP
1467  */
make_receive_sock(struct net * net,int id)1468 static struct socket *make_receive_sock(struct net *net, int id)
1469 {
1470 	struct netns_ipvs *ipvs = net_ipvs(net);
1471 	/* multicast addr */
1472 	struct sockaddr_in mcast_addr = {
1473 		.sin_family		= AF_INET,
1474 		.sin_port		= cpu_to_be16(IP_VS_SYNC_PORT + id),
1475 		.sin_addr.s_addr	= cpu_to_be32(IP_VS_SYNC_GROUP),
1476 	};
1477 	struct socket *sock;
1478 	int result;
1479 
1480 	/* First create a socket */
1481 	result = sock_create_kern(PF_INET, SOCK_DGRAM, IPPROTO_UDP, &sock);
1482 	if (result < 0) {
1483 		pr_err("Error during creation of socket; terminating\n");
1484 		return ERR_PTR(result);
1485 	}
1486 	/*
1487 	 * Kernel sockets that are a part of a namespace, should not
1488 	 * hold a reference to a namespace in order to allow to stop it.
1489 	 * After sk_change_net should be released using sk_release_kernel.
1490 	 */
1491 	sk_change_net(sock->sk, net);
1492 	/* it is equivalent to the REUSEADDR option in user-space */
1493 	sock->sk->sk_reuse = SK_CAN_REUSE;
1494 	result = sysctl_sync_sock_size(ipvs);
1495 	if (result > 0)
1496 		set_sock_size(sock->sk, 0, result);
1497 
1498 	result = sock->ops->bind(sock, (struct sockaddr *) &mcast_addr,
1499 			sizeof(struct sockaddr));
1500 	if (result < 0) {
1501 		pr_err("Error binding to the multicast addr\n");
1502 		goto error;
1503 	}
1504 
1505 	/* join the multicast group */
1506 	result = join_mcast_group(sock->sk,
1507 			(struct in_addr *) &mcast_addr.sin_addr,
1508 			ipvs->backup_mcast_ifn);
1509 	if (result < 0) {
1510 		pr_err("Error joining to the multicast group\n");
1511 		goto error;
1512 	}
1513 
1514 	return sock;
1515 
1516 error:
1517 	sk_release_kernel(sock->sk);
1518 	return ERR_PTR(result);
1519 }
1520 
1521 
1522 static int
ip_vs_send_async(struct socket * sock,const char * buffer,const size_t length)1523 ip_vs_send_async(struct socket *sock, const char *buffer, const size_t length)
1524 {
1525 	struct msghdr	msg = {.msg_flags = MSG_DONTWAIT|MSG_NOSIGNAL};
1526 	struct kvec	iov;
1527 	int		len;
1528 
1529 	EnterFunction(7);
1530 	iov.iov_base     = (void *)buffer;
1531 	iov.iov_len      = length;
1532 
1533 	len = kernel_sendmsg(sock, &msg, &iov, 1, (size_t)(length));
1534 
1535 	LeaveFunction(7);
1536 	return len;
1537 }
1538 
1539 static int
ip_vs_send_sync_msg(struct socket * sock,struct ip_vs_sync_mesg * msg)1540 ip_vs_send_sync_msg(struct socket *sock, struct ip_vs_sync_mesg *msg)
1541 {
1542 	int msize;
1543 	int ret;
1544 
1545 	msize = ntohs(msg->size);
1546 
1547 	ret = ip_vs_send_async(sock, (char *)msg, msize);
1548 	if (ret >= 0 || ret == -EAGAIN)
1549 		return ret;
1550 	pr_err("ip_vs_send_async error %d\n", ret);
1551 	return 0;
1552 }
1553 
1554 static int
ip_vs_receive(struct socket * sock,char * buffer,const size_t buflen)1555 ip_vs_receive(struct socket *sock, char *buffer, const size_t buflen)
1556 {
1557 	struct msghdr		msg = {NULL,};
1558 	struct kvec		iov;
1559 	int			len;
1560 
1561 	EnterFunction(7);
1562 
1563 	/* Receive a packet */
1564 	iov.iov_base     = buffer;
1565 	iov.iov_len      = (size_t)buflen;
1566 
1567 	len = kernel_recvmsg(sock, &msg, &iov, 1, buflen, MSG_DONTWAIT);
1568 
1569 	if (len < 0)
1570 		return len;
1571 
1572 	LeaveFunction(7);
1573 	return len;
1574 }
1575 
1576 /* Wakeup the master thread for sending */
master_wakeup_work_handler(struct work_struct * work)1577 static void master_wakeup_work_handler(struct work_struct *work)
1578 {
1579 	struct ipvs_master_sync_state *ms =
1580 		container_of(work, struct ipvs_master_sync_state,
1581 			     master_wakeup_work.work);
1582 	struct netns_ipvs *ipvs = ms->ipvs;
1583 
1584 	spin_lock_bh(&ipvs->sync_lock);
1585 	if (ms->sync_queue_len &&
1586 	    ms->sync_queue_delay < IPVS_SYNC_WAKEUP_RATE) {
1587 		ms->sync_queue_delay = IPVS_SYNC_WAKEUP_RATE;
1588 		wake_up_process(ms->master_thread);
1589 	}
1590 	spin_unlock_bh(&ipvs->sync_lock);
1591 }
1592 
1593 /* Get next buffer to send */
1594 static inline struct ip_vs_sync_buff *
next_sync_buff(struct netns_ipvs * ipvs,struct ipvs_master_sync_state * ms)1595 next_sync_buff(struct netns_ipvs *ipvs, struct ipvs_master_sync_state *ms)
1596 {
1597 	struct ip_vs_sync_buff *sb;
1598 
1599 	sb = sb_dequeue(ipvs, ms);
1600 	if (sb)
1601 		return sb;
1602 	/* Do not delay entries in buffer for more than 2 seconds */
1603 	return get_curr_sync_buff(ipvs, ms, IPVS_SYNC_FLUSH_TIME);
1604 }
1605 
sync_thread_master(void * data)1606 static int sync_thread_master(void *data)
1607 {
1608 	struct ip_vs_sync_thread_data *tinfo = data;
1609 	struct netns_ipvs *ipvs = net_ipvs(tinfo->net);
1610 	struct ipvs_master_sync_state *ms = &ipvs->ms[tinfo->id];
1611 	struct sock *sk = tinfo->sock->sk;
1612 	struct ip_vs_sync_buff *sb;
1613 
1614 	pr_info("sync thread started: state = MASTER, mcast_ifn = %s, "
1615 		"syncid = %d, id = %d\n",
1616 		ipvs->master_mcast_ifn, ipvs->master_syncid, tinfo->id);
1617 
1618 	for (;;) {
1619 		sb = next_sync_buff(ipvs, ms);
1620 		if (unlikely(kthread_should_stop()))
1621 			break;
1622 		if (!sb) {
1623 			schedule_timeout(IPVS_SYNC_CHECK_PERIOD);
1624 			continue;
1625 		}
1626 		while (ip_vs_send_sync_msg(tinfo->sock, sb->mesg) < 0) {
1627 			int ret = 0;
1628 
1629 			__wait_event_interruptible(*sk_sleep(sk),
1630 						   sock_writeable(sk) ||
1631 						   kthread_should_stop(),
1632 						   ret);
1633 			if (unlikely(kthread_should_stop()))
1634 				goto done;
1635 		}
1636 		ip_vs_sync_buff_release(sb);
1637 	}
1638 
1639 done:
1640 	__set_current_state(TASK_RUNNING);
1641 	if (sb)
1642 		ip_vs_sync_buff_release(sb);
1643 
1644 	/* clean up the sync_buff queue */
1645 	while ((sb = sb_dequeue(ipvs, ms)))
1646 		ip_vs_sync_buff_release(sb);
1647 	__set_current_state(TASK_RUNNING);
1648 
1649 	/* clean up the current sync_buff */
1650 	sb = get_curr_sync_buff(ipvs, ms, 0);
1651 	if (sb)
1652 		ip_vs_sync_buff_release(sb);
1653 
1654 	/* release the sending multicast socket */
1655 	sk_release_kernel(tinfo->sock->sk);
1656 	kfree(tinfo);
1657 
1658 	return 0;
1659 }
1660 
1661 
sync_thread_backup(void * data)1662 static int sync_thread_backup(void *data)
1663 {
1664 	struct ip_vs_sync_thread_data *tinfo = data;
1665 	struct netns_ipvs *ipvs = net_ipvs(tinfo->net);
1666 	int len;
1667 
1668 	pr_info("sync thread started: state = BACKUP, mcast_ifn = %s, "
1669 		"syncid = %d, id = %d\n",
1670 		ipvs->backup_mcast_ifn, ipvs->backup_syncid, tinfo->id);
1671 
1672 	while (!kthread_should_stop()) {
1673 		wait_event_interruptible(*sk_sleep(tinfo->sock->sk),
1674 			 !skb_queue_empty(&tinfo->sock->sk->sk_receive_queue)
1675 			 || kthread_should_stop());
1676 
1677 		/* do we have data now? */
1678 		while (!skb_queue_empty(&(tinfo->sock->sk->sk_receive_queue))) {
1679 			len = ip_vs_receive(tinfo->sock, tinfo->buf,
1680 					ipvs->recv_mesg_maxlen);
1681 			if (len <= 0) {
1682 				if (len != -EAGAIN)
1683 					pr_err("receiving message error\n");
1684 				break;
1685 			}
1686 
1687 			ip_vs_process_message(tinfo->net, tinfo->buf, len);
1688 		}
1689 	}
1690 
1691 	/* release the sending multicast socket */
1692 	sk_release_kernel(tinfo->sock->sk);
1693 	kfree(tinfo->buf);
1694 	kfree(tinfo);
1695 
1696 	return 0;
1697 }
1698 
1699 
start_sync_thread(struct net * net,int state,char * mcast_ifn,__u8 syncid)1700 int start_sync_thread(struct net *net, int state, char *mcast_ifn, __u8 syncid)
1701 {
1702 	struct ip_vs_sync_thread_data *tinfo;
1703 	struct task_struct **array = NULL, *task;
1704 	struct socket *sock;
1705 	struct netns_ipvs *ipvs = net_ipvs(net);
1706 	char *name;
1707 	int (*threadfn)(void *data);
1708 	int id, count;
1709 	int result = -ENOMEM;
1710 
1711 	IP_VS_DBG(7, "%s(): pid %d\n", __func__, task_pid_nr(current));
1712 	IP_VS_DBG(7, "Each ip_vs_sync_conn entry needs %Zd bytes\n",
1713 		  sizeof(struct ip_vs_sync_conn_v0));
1714 
1715 	if (!ipvs->sync_state) {
1716 		count = clamp(sysctl_sync_ports(ipvs), 1, IPVS_SYNC_PORTS_MAX);
1717 		ipvs->threads_mask = count - 1;
1718 	} else
1719 		count = ipvs->threads_mask + 1;
1720 
1721 	if (state == IP_VS_STATE_MASTER) {
1722 		if (ipvs->ms)
1723 			return -EEXIST;
1724 
1725 		strlcpy(ipvs->master_mcast_ifn, mcast_ifn,
1726 			sizeof(ipvs->master_mcast_ifn));
1727 		ipvs->master_syncid = syncid;
1728 		name = "ipvs-m:%d:%d";
1729 		threadfn = sync_thread_master;
1730 	} else if (state == IP_VS_STATE_BACKUP) {
1731 		if (ipvs->backup_threads)
1732 			return -EEXIST;
1733 
1734 		strlcpy(ipvs->backup_mcast_ifn, mcast_ifn,
1735 			sizeof(ipvs->backup_mcast_ifn));
1736 		ipvs->backup_syncid = syncid;
1737 		name = "ipvs-b:%d:%d";
1738 		threadfn = sync_thread_backup;
1739 	} else {
1740 		return -EINVAL;
1741 	}
1742 
1743 	if (state == IP_VS_STATE_MASTER) {
1744 		struct ipvs_master_sync_state *ms;
1745 
1746 		ipvs->ms = kzalloc(count * sizeof(ipvs->ms[0]), GFP_KERNEL);
1747 		if (!ipvs->ms)
1748 			goto out;
1749 		ms = ipvs->ms;
1750 		for (id = 0; id < count; id++, ms++) {
1751 			INIT_LIST_HEAD(&ms->sync_queue);
1752 			ms->sync_queue_len = 0;
1753 			ms->sync_queue_delay = 0;
1754 			INIT_DELAYED_WORK(&ms->master_wakeup_work,
1755 					  master_wakeup_work_handler);
1756 			ms->ipvs = ipvs;
1757 		}
1758 	} else {
1759 		array = kzalloc(count * sizeof(struct task_struct *),
1760 				GFP_KERNEL);
1761 		if (!array)
1762 			goto out;
1763 	}
1764 	set_sync_mesg_maxlen(net, state);
1765 
1766 	tinfo = NULL;
1767 	for (id = 0; id < count; id++) {
1768 		if (state == IP_VS_STATE_MASTER)
1769 			sock = make_send_sock(net, id);
1770 		else
1771 			sock = make_receive_sock(net, id);
1772 		if (IS_ERR(sock)) {
1773 			result = PTR_ERR(sock);
1774 			goto outtinfo;
1775 		}
1776 		tinfo = kmalloc(sizeof(*tinfo), GFP_KERNEL);
1777 		if (!tinfo)
1778 			goto outsocket;
1779 		tinfo->net = net;
1780 		tinfo->sock = sock;
1781 		if (state == IP_VS_STATE_BACKUP) {
1782 			tinfo->buf = kmalloc(ipvs->recv_mesg_maxlen,
1783 					     GFP_KERNEL);
1784 			if (!tinfo->buf)
1785 				goto outtinfo;
1786 		} else {
1787 			tinfo->buf = NULL;
1788 		}
1789 		tinfo->id = id;
1790 
1791 		task = kthread_run(threadfn, tinfo, name, ipvs->gen, id);
1792 		if (IS_ERR(task)) {
1793 			result = PTR_ERR(task);
1794 			goto outtinfo;
1795 		}
1796 		tinfo = NULL;
1797 		if (state == IP_VS_STATE_MASTER)
1798 			ipvs->ms[id].master_thread = task;
1799 		else
1800 			array[id] = task;
1801 	}
1802 
1803 	/* mark as active */
1804 
1805 	if (state == IP_VS_STATE_BACKUP)
1806 		ipvs->backup_threads = array;
1807 	spin_lock_bh(&ipvs->sync_buff_lock);
1808 	ipvs->sync_state |= state;
1809 	spin_unlock_bh(&ipvs->sync_buff_lock);
1810 
1811 	/* increase the module use count */
1812 	ip_vs_use_count_inc();
1813 
1814 	return 0;
1815 
1816 outsocket:
1817 	sk_release_kernel(sock->sk);
1818 
1819 outtinfo:
1820 	if (tinfo) {
1821 		sk_release_kernel(tinfo->sock->sk);
1822 		kfree(tinfo->buf);
1823 		kfree(tinfo);
1824 	}
1825 	count = id;
1826 	while (count-- > 0) {
1827 		if (state == IP_VS_STATE_MASTER)
1828 			kthread_stop(ipvs->ms[count].master_thread);
1829 		else
1830 			kthread_stop(array[count]);
1831 	}
1832 	kfree(array);
1833 
1834 out:
1835 	if (!(ipvs->sync_state & IP_VS_STATE_MASTER)) {
1836 		kfree(ipvs->ms);
1837 		ipvs->ms = NULL;
1838 	}
1839 	return result;
1840 }
1841 
1842 
stop_sync_thread(struct net * net,int state)1843 int stop_sync_thread(struct net *net, int state)
1844 {
1845 	struct netns_ipvs *ipvs = net_ipvs(net);
1846 	struct task_struct **array;
1847 	int id;
1848 	int retc = -EINVAL;
1849 
1850 	IP_VS_DBG(7, "%s(): pid %d\n", __func__, task_pid_nr(current));
1851 
1852 	if (state == IP_VS_STATE_MASTER) {
1853 		if (!ipvs->ms)
1854 			return -ESRCH;
1855 
1856 		/*
1857 		 * The lock synchronizes with sb_queue_tail(), so that we don't
1858 		 * add sync buffers to the queue, when we are already in
1859 		 * progress of stopping the master sync daemon.
1860 		 */
1861 
1862 		spin_lock_bh(&ipvs->sync_buff_lock);
1863 		spin_lock(&ipvs->sync_lock);
1864 		ipvs->sync_state &= ~IP_VS_STATE_MASTER;
1865 		spin_unlock(&ipvs->sync_lock);
1866 		spin_unlock_bh(&ipvs->sync_buff_lock);
1867 
1868 		retc = 0;
1869 		for (id = ipvs->threads_mask; id >= 0; id--) {
1870 			struct ipvs_master_sync_state *ms = &ipvs->ms[id];
1871 			int ret;
1872 
1873 			pr_info("stopping master sync thread %d ...\n",
1874 				task_pid_nr(ms->master_thread));
1875 			cancel_delayed_work_sync(&ms->master_wakeup_work);
1876 			ret = kthread_stop(ms->master_thread);
1877 			if (retc >= 0)
1878 				retc = ret;
1879 		}
1880 		kfree(ipvs->ms);
1881 		ipvs->ms = NULL;
1882 	} else if (state == IP_VS_STATE_BACKUP) {
1883 		if (!ipvs->backup_threads)
1884 			return -ESRCH;
1885 
1886 		ipvs->sync_state &= ~IP_VS_STATE_BACKUP;
1887 		array = ipvs->backup_threads;
1888 		retc = 0;
1889 		for (id = ipvs->threads_mask; id >= 0; id--) {
1890 			int ret;
1891 
1892 			pr_info("stopping backup sync thread %d ...\n",
1893 				task_pid_nr(array[id]));
1894 			ret = kthread_stop(array[id]);
1895 			if (retc >= 0)
1896 				retc = ret;
1897 		}
1898 		kfree(array);
1899 		ipvs->backup_threads = NULL;
1900 	}
1901 
1902 	/* decrease the module use count */
1903 	ip_vs_use_count_dec();
1904 
1905 	return retc;
1906 }
1907 
1908 /*
1909  * Initialize data struct for each netns
1910  */
ip_vs_sync_net_init(struct net * net)1911 int __net_init ip_vs_sync_net_init(struct net *net)
1912 {
1913 	struct netns_ipvs *ipvs = net_ipvs(net);
1914 
1915 	__mutex_init(&ipvs->sync_mutex, "ipvs->sync_mutex", &__ipvs_sync_key);
1916 	spin_lock_init(&ipvs->sync_lock);
1917 	spin_lock_init(&ipvs->sync_buff_lock);
1918 	return 0;
1919 }
1920 
ip_vs_sync_net_cleanup(struct net * net)1921 void ip_vs_sync_net_cleanup(struct net *net)
1922 {
1923 	int retc;
1924 	struct netns_ipvs *ipvs = net_ipvs(net);
1925 
1926 	mutex_lock(&ipvs->sync_mutex);
1927 	retc = stop_sync_thread(net, IP_VS_STATE_MASTER);
1928 	if (retc && retc != -ESRCH)
1929 		pr_err("Failed to stop Master Daemon\n");
1930 
1931 	retc = stop_sync_thread(net, IP_VS_STATE_BACKUP);
1932 	if (retc && retc != -ESRCH)
1933 		pr_err("Failed to stop Backup Daemon\n");
1934 	mutex_unlock(&ipvs->sync_mutex);
1935 }
1936