xref: /openbmc/linux/net/netfilter/ipvs/ip_vs_sync.c (revision c889a99a)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * IPVS         An implementation of the IP virtual server support for the
4  *              LINUX operating system.  IPVS is now implemented as a module
5  *              over the NetFilter framework. IPVS can be used to build a
6  *              high-performance and highly available server based on a
7  *              cluster of servers.
8  *
9  * Version 1,   is capable of handling both version 0 and 1 messages.
10  *              Version 0 is the plain old format.
11  *              Note Version 0 receivers will just drop Ver 1 messages.
12  *              Version 1 is capable of handle IPv6, Persistence data,
13  *              time-outs, and firewall marks.
14  *              In ver.1 "ip_vs_sync_conn_options" will be sent in netw. order.
15  *              Ver. 0 can be turned on by sysctl -w net.ipv4.vs.sync_version=0
16  *
17  * Definitions  Message: is a complete datagram
18  *              Sync_conn: is a part of a Message
19  *              Param Data is an option to a Sync_conn.
20  *
21  * Authors:     Wensong Zhang <wensong@linuxvirtualserver.org>
22  *
23  * ip_vs_sync:  sync connection info from master load balancer to backups
24  *              through multicast
25  *
26  * Changes:
27  *	Alexandre Cassen	:	Added master & backup support at a time.
28  *	Alexandre Cassen	:	Added SyncID support for incoming sync
29  *					messages filtering.
30  *	Justin Ossevoort	:	Fix endian problem on sync message size.
31  *	Hans Schillstrom	:	Added Version 1: i.e. IPv6,
32  *					Persistence support, fwmark and time-out.
33  */
34 
35 #define KMSG_COMPONENT "IPVS"
36 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
37 
38 #include <linux/module.h>
39 #include <linux/slab.h>
40 #include <linux/inetdevice.h>
41 #include <linux/net.h>
42 #include <linux/completion.h>
43 #include <linux/delay.h>
44 #include <linux/skbuff.h>
45 #include <linux/in.h>
46 #include <linux/igmp.h>                 /* for ip_mc_join_group */
47 #include <linux/udp.h>
48 #include <linux/err.h>
49 #include <linux/kthread.h>
50 #include <linux/wait.h>
51 #include <linux/kernel.h>
52 #include <linux/sched/signal.h>
53 
54 #include <asm/unaligned.h>		/* Used for ntoh_seq and hton_seq */
55 
56 #include <net/ip.h>
57 #include <net/sock.h>
58 
59 #include <net/ip_vs.h>
60 
61 #define IP_VS_SYNC_GROUP 0xe0000051    /* multicast addr - 224.0.0.81 */
62 #define IP_VS_SYNC_PORT  8848          /* multicast port */
63 
64 #define SYNC_PROTO_VER  1		/* Protocol version in header */
65 
66 static struct lock_class_key __ipvs_sync_key;
67 /*
68  *	IPVS sync connection entry
69  *	Version 0, i.e. original version.
70  */
71 struct ip_vs_sync_conn_v0 {
72 	__u8			reserved;
73 
74 	/* Protocol, addresses and port numbers */
75 	__u8			protocol;       /* Which protocol (TCP/UDP) */
76 	__be16			cport;
77 	__be16                  vport;
78 	__be16                  dport;
79 	__be32                  caddr;          /* client address */
80 	__be32                  vaddr;          /* virtual address */
81 	__be32                  daddr;          /* destination address */
82 
83 	/* Flags and state transition */
84 	__be16                  flags;          /* status flags */
85 	__be16                  state;          /* state info */
86 
87 	/* The sequence options start here */
88 };
89 
90 struct ip_vs_sync_conn_options {
91 	struct ip_vs_seq        in_seq;         /* incoming seq. struct */
92 	struct ip_vs_seq        out_seq;        /* outgoing seq. struct */
93 };
94 
95 /*
96      Sync Connection format (sync_conn)
97 
98        0                   1                   2                   3
99        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
100       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
101       |    Type       |    Protocol   | Ver.  |        Size           |
102       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
103       |                             Flags                             |
104       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
105       |            State              |         cport                 |
106       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
107       |            vport              |         dport                 |
108       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
109       |                             fwmark                            |
110       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
111       |                             timeout  (in sec.)                |
112       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
113       |                              ...                              |
114       |                        IP-Addresses  (v4 or v6)               |
115       |                              ...                              |
116       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
117   Optional Parameters.
118       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
119       | Param. Type    | Param. Length |   Param. data                |
120       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+                               |
121       |                              ...                              |
122       |                               +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
123       |                               | Param Type    | Param. Length |
124       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
125       |                           Param  data                         |
126       |         Last Param data should be padded for 32 bit alignment |
127       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
128 */
129 
130 /*
131  *  Type 0, IPv4 sync connection format
132  */
133 struct ip_vs_sync_v4 {
134 	__u8			type;
135 	__u8			protocol;	/* Which protocol (TCP/UDP) */
136 	__be16			ver_size;	/* Version msb 4 bits */
137 	/* Flags and state transition */
138 	__be32			flags;		/* status flags */
139 	__be16			state;		/* state info 	*/
140 	/* Protocol, addresses and port numbers */
141 	__be16			cport;
142 	__be16			vport;
143 	__be16			dport;
144 	__be32			fwmark;		/* Firewall mark from skb */
145 	__be32			timeout;	/* cp timeout */
146 	__be32			caddr;		/* client address */
147 	__be32			vaddr;		/* virtual address */
148 	__be32			daddr;		/* destination address */
149 	/* The sequence options start here */
150 	/* PE data padded to 32bit alignment after seq. options */
151 };
152 /*
153  * Type 2 messages IPv6
154  */
155 struct ip_vs_sync_v6 {
156 	__u8			type;
157 	__u8			protocol;	/* Which protocol (TCP/UDP) */
158 	__be16			ver_size;	/* Version msb 4 bits */
159 	/* Flags and state transition */
160 	__be32			flags;		/* status flags */
161 	__be16			state;		/* state info 	*/
162 	/* Protocol, addresses and port numbers */
163 	__be16			cport;
164 	__be16			vport;
165 	__be16			dport;
166 	__be32			fwmark;		/* Firewall mark from skb */
167 	__be32			timeout;	/* cp timeout */
168 	struct in6_addr		caddr;		/* client address */
169 	struct in6_addr		vaddr;		/* virtual address */
170 	struct in6_addr		daddr;		/* destination address */
171 	/* The sequence options start here */
172 	/* PE data padded to 32bit alignment after seq. options */
173 };
174 
175 union ip_vs_sync_conn {
176 	struct ip_vs_sync_v4	v4;
177 	struct ip_vs_sync_v6	v6;
178 };
179 
180 /* Bits in Type field in above */
181 #define STYPE_INET6		0
182 #define STYPE_F_INET6		(1 << STYPE_INET6)
183 
184 #define SVER_SHIFT		12		/* Shift to get version */
185 #define SVER_MASK		0x0fff		/* Mask to strip version */
186 
187 #define IPVS_OPT_SEQ_DATA	1
188 #define IPVS_OPT_PE_DATA	2
189 #define IPVS_OPT_PE_NAME	3
190 #define IPVS_OPT_PARAM		7
191 
192 #define IPVS_OPT_F_SEQ_DATA	(1 << (IPVS_OPT_SEQ_DATA-1))
193 #define IPVS_OPT_F_PE_DATA	(1 << (IPVS_OPT_PE_DATA-1))
194 #define IPVS_OPT_F_PE_NAME	(1 << (IPVS_OPT_PE_NAME-1))
195 #define IPVS_OPT_F_PARAM	(1 << (IPVS_OPT_PARAM-1))
196 
197 struct ip_vs_sync_thread_data {
198 	struct task_struct *task;
199 	struct netns_ipvs *ipvs;
200 	struct socket *sock;
201 	char *buf;
202 	int id;
203 };
204 
205 /* Version 0 definition of packet sizes */
206 #define SIMPLE_CONN_SIZE  (sizeof(struct ip_vs_sync_conn_v0))
207 #define FULL_CONN_SIZE  \
208 (sizeof(struct ip_vs_sync_conn_v0) + sizeof(struct ip_vs_sync_conn_options))
209 
210 
211 /*
212   The master mulitcasts messages (Datagrams) to the backup load balancers
213   in the following format.
214 
215  Version 1:
216   Note, first byte should be Zero, so ver 0 receivers will drop the packet.
217 
218        0                   1                   2                   3
219        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
220       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
221       |      0        |    SyncID     |            Size               |
222       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
223       |  Count Conns  |    Version    |    Reserved, set to Zero      |
224       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
225       |                                                               |
226       |                    IPVS Sync Connection (1)                   |
227       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
228       |                            .                                  |
229       ~                            .                                  ~
230       |                            .                                  |
231       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
232       |                                                               |
233       |                    IPVS Sync Connection (n)                   |
234       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
235 
236  Version 0 Header
237        0                   1                   2                   3
238        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
239       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
240       |  Count Conns  |    SyncID     |            Size               |
241       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
242       |                    IPVS Sync Connection (1)                   |
243 */
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 union ipvs_sockaddr {
266 	struct sockaddr_in	in;
267 	struct sockaddr_in6	in6;
268 };
269 
270 struct ip_vs_sync_buff {
271 	struct list_head        list;
272 	unsigned long           firstuse;
273 
274 	/* pointers for the message data */
275 	struct ip_vs_sync_mesg  *mesg;
276 	unsigned char           *head;
277 	unsigned char           *end;
278 };
279 
280 /*
281  * Copy of struct ip_vs_seq
282  * From unaligned network order to aligned host order
283  */
ntoh_seq(struct ip_vs_seq * no,struct ip_vs_seq * ho)284 static void ntoh_seq(struct ip_vs_seq *no, struct ip_vs_seq *ho)
285 {
286 	memset(ho, 0, sizeof(*ho));
287 	ho->init_seq       = get_unaligned_be32(&no->init_seq);
288 	ho->delta          = get_unaligned_be32(&no->delta);
289 	ho->previous_delta = get_unaligned_be32(&no->previous_delta);
290 }
291 
292 /*
293  * Copy of struct ip_vs_seq
294  * From Aligned host order to unaligned network order
295  */
hton_seq(struct ip_vs_seq * ho,struct ip_vs_seq * no)296 static void hton_seq(struct ip_vs_seq *ho, struct ip_vs_seq *no)
297 {
298 	put_unaligned_be32(ho->init_seq, &no->init_seq);
299 	put_unaligned_be32(ho->delta, &no->delta);
300 	put_unaligned_be32(ho->previous_delta, &no->previous_delta);
301 }
302 
303 static inline struct ip_vs_sync_buff *
sb_dequeue(struct netns_ipvs * ipvs,struct ipvs_master_sync_state * ms)304 sb_dequeue(struct netns_ipvs *ipvs, struct ipvs_master_sync_state *ms)
305 {
306 	struct ip_vs_sync_buff *sb;
307 
308 	spin_lock_bh(&ipvs->sync_lock);
309 	if (list_empty(&ms->sync_queue)) {
310 		sb = NULL;
311 		__set_current_state(TASK_INTERRUPTIBLE);
312 	} else {
313 		sb = list_entry(ms->sync_queue.next, struct ip_vs_sync_buff,
314 				list);
315 		list_del(&sb->list);
316 		ms->sync_queue_len--;
317 		if (!ms->sync_queue_len)
318 			ms->sync_queue_delay = 0;
319 	}
320 	spin_unlock_bh(&ipvs->sync_lock);
321 
322 	return sb;
323 }
324 
325 /*
326  * Create a new sync buffer for Version 1 proto.
327  */
328 static inline struct ip_vs_sync_buff *
ip_vs_sync_buff_create(struct netns_ipvs * ipvs,unsigned int len)329 ip_vs_sync_buff_create(struct netns_ipvs *ipvs, unsigned int len)
330 {
331 	struct ip_vs_sync_buff *sb;
332 
333 	if (!(sb=kmalloc(sizeof(struct ip_vs_sync_buff), GFP_ATOMIC)))
334 		return NULL;
335 
336 	len = max_t(unsigned int, len + sizeof(struct ip_vs_sync_mesg),
337 		    ipvs->mcfg.sync_maxlen);
338 	sb->mesg = kmalloc(len, GFP_ATOMIC);
339 	if (!sb->mesg) {
340 		kfree(sb);
341 		return NULL;
342 	}
343 	sb->mesg->reserved = 0;  /* old nr_conns i.e. must be zero now */
344 	sb->mesg->version = SYNC_PROTO_VER;
345 	sb->mesg->syncid = ipvs->mcfg.syncid;
346 	sb->mesg->size = htons(sizeof(struct ip_vs_sync_mesg));
347 	sb->mesg->nr_conns = 0;
348 	sb->mesg->spare = 0;
349 	sb->head = (unsigned char *)sb->mesg + sizeof(struct ip_vs_sync_mesg);
350 	sb->end = (unsigned char *)sb->mesg + len;
351 
352 	sb->firstuse = jiffies;
353 	return sb;
354 }
355 
ip_vs_sync_buff_release(struct ip_vs_sync_buff * sb)356 static inline void ip_vs_sync_buff_release(struct ip_vs_sync_buff *sb)
357 {
358 	kfree(sb->mesg);
359 	kfree(sb);
360 }
361 
sb_queue_tail(struct netns_ipvs * ipvs,struct ipvs_master_sync_state * ms)362 static inline void sb_queue_tail(struct netns_ipvs *ipvs,
363 				 struct ipvs_master_sync_state *ms)
364 {
365 	struct ip_vs_sync_buff *sb = ms->sync_buff;
366 
367 	spin_lock(&ipvs->sync_lock);
368 	if (ipvs->sync_state & IP_VS_STATE_MASTER &&
369 	    ms->sync_queue_len < sysctl_sync_qlen_max(ipvs)) {
370 		if (!ms->sync_queue_len)
371 			schedule_delayed_work(&ms->master_wakeup_work,
372 					      max(IPVS_SYNC_SEND_DELAY, 1));
373 		ms->sync_queue_len++;
374 		list_add_tail(&sb->list, &ms->sync_queue);
375 		if ((++ms->sync_queue_delay) == IPVS_SYNC_WAKEUP_RATE) {
376 			int id = (int)(ms - ipvs->ms);
377 
378 			wake_up_process(ipvs->master_tinfo[id].task);
379 		}
380 	} else
381 		ip_vs_sync_buff_release(sb);
382 	spin_unlock(&ipvs->sync_lock);
383 }
384 
385 /*
386  *	Get the current sync buffer if it has been created for more
387  *	than the specified time or the specified time is zero.
388  */
389 static inline struct ip_vs_sync_buff *
get_curr_sync_buff(struct netns_ipvs * ipvs,struct ipvs_master_sync_state * ms,unsigned long time)390 get_curr_sync_buff(struct netns_ipvs *ipvs, struct ipvs_master_sync_state *ms,
391 		   unsigned long time)
392 {
393 	struct ip_vs_sync_buff *sb;
394 
395 	spin_lock_bh(&ipvs->sync_buff_lock);
396 	sb = ms->sync_buff;
397 	if (sb && time_after_eq(jiffies - sb->firstuse, time)) {
398 		ms->sync_buff = NULL;
399 		__set_current_state(TASK_RUNNING);
400 	} else
401 		sb = NULL;
402 	spin_unlock_bh(&ipvs->sync_buff_lock);
403 	return sb;
404 }
405 
406 static inline int
select_master_thread_id(struct netns_ipvs * ipvs,struct ip_vs_conn * cp)407 select_master_thread_id(struct netns_ipvs *ipvs, struct ip_vs_conn *cp)
408 {
409 	return ((long) cp >> (1 + ilog2(sizeof(*cp)))) & ipvs->threads_mask;
410 }
411 
412 /*
413  * Create a new sync buffer for Version 0 proto.
414  */
415 static inline struct ip_vs_sync_buff *
ip_vs_sync_buff_create_v0(struct netns_ipvs * ipvs,unsigned int len)416 ip_vs_sync_buff_create_v0(struct netns_ipvs *ipvs, unsigned int len)
417 {
418 	struct ip_vs_sync_buff *sb;
419 	struct ip_vs_sync_mesg_v0 *mesg;
420 
421 	if (!(sb=kmalloc(sizeof(struct ip_vs_sync_buff), GFP_ATOMIC)))
422 		return NULL;
423 
424 	len = max_t(unsigned int, len + sizeof(struct ip_vs_sync_mesg_v0),
425 		    ipvs->mcfg.sync_maxlen);
426 	sb->mesg = kmalloc(len, GFP_ATOMIC);
427 	if (!sb->mesg) {
428 		kfree(sb);
429 		return NULL;
430 	}
431 	mesg = (struct ip_vs_sync_mesg_v0 *)sb->mesg;
432 	mesg->nr_conns = 0;
433 	mesg->syncid = ipvs->mcfg.syncid;
434 	mesg->size = htons(sizeof(struct ip_vs_sync_mesg_v0));
435 	sb->head = (unsigned char *)mesg + sizeof(struct ip_vs_sync_mesg_v0);
436 	sb->end = (unsigned char *)mesg + len;
437 	sb->firstuse = jiffies;
438 	return sb;
439 }
440 
441 /* Check if connection is controlled by persistence */
in_persistence(struct ip_vs_conn * cp)442 static inline bool in_persistence(struct ip_vs_conn *cp)
443 {
444 	for (cp = cp->control; cp; cp = cp->control) {
445 		if (cp->flags & IP_VS_CONN_F_TEMPLATE)
446 			return true;
447 	}
448 	return false;
449 }
450 
451 /* Check if conn should be synced.
452  * pkts: conn packets, use sysctl_sync_threshold to avoid packet check
453  * - (1) sync_refresh_period: reduce sync rate. Additionally, retry
454  *	sync_retries times with period of sync_refresh_period/8
455  * - (2) if both sync_refresh_period and sync_period are 0 send sync only
456  *	for state changes or only once when pkts matches sync_threshold
457  * - (3) templates: rate can be reduced only with sync_refresh_period or
458  *	with (2)
459  */
ip_vs_sync_conn_needed(struct netns_ipvs * ipvs,struct ip_vs_conn * cp,int pkts)460 static int ip_vs_sync_conn_needed(struct netns_ipvs *ipvs,
461 				  struct ip_vs_conn *cp, int pkts)
462 {
463 	unsigned long orig = READ_ONCE(cp->sync_endtime);
464 	unsigned long now = jiffies;
465 	unsigned long n = (now + cp->timeout) & ~3UL;
466 	unsigned int sync_refresh_period;
467 	int sync_period;
468 	int force;
469 
470 	/* Check if we sync in current state */
471 	if (unlikely(cp->flags & IP_VS_CONN_F_TEMPLATE))
472 		force = 0;
473 	else if (unlikely(sysctl_sync_persist_mode(ipvs) && in_persistence(cp)))
474 		return 0;
475 	else if (likely(cp->protocol == IPPROTO_TCP)) {
476 		if (!((1 << cp->state) &
477 		      ((1 << IP_VS_TCP_S_ESTABLISHED) |
478 		       (1 << IP_VS_TCP_S_FIN_WAIT) |
479 		       (1 << IP_VS_TCP_S_CLOSE) |
480 		       (1 << IP_VS_TCP_S_CLOSE_WAIT) |
481 		       (1 << IP_VS_TCP_S_TIME_WAIT))))
482 			return 0;
483 		force = cp->state != cp->old_state;
484 		if (force && cp->state != IP_VS_TCP_S_ESTABLISHED)
485 			goto set;
486 	} else if (unlikely(cp->protocol == IPPROTO_SCTP)) {
487 		if (!((1 << cp->state) &
488 		      ((1 << IP_VS_SCTP_S_ESTABLISHED) |
489 		       (1 << IP_VS_SCTP_S_SHUTDOWN_SENT) |
490 		       (1 << IP_VS_SCTP_S_SHUTDOWN_RECEIVED) |
491 		       (1 << IP_VS_SCTP_S_SHUTDOWN_ACK_SENT) |
492 		       (1 << IP_VS_SCTP_S_CLOSED))))
493 			return 0;
494 		force = cp->state != cp->old_state;
495 		if (force && cp->state != IP_VS_SCTP_S_ESTABLISHED)
496 			goto set;
497 	} else {
498 		/* UDP or another protocol with single state */
499 		force = 0;
500 	}
501 
502 	sync_refresh_period = sysctl_sync_refresh_period(ipvs);
503 	if (sync_refresh_period > 0) {
504 		long diff = n - orig;
505 		long min_diff = max(cp->timeout >> 1, 10UL * HZ);
506 
507 		/* Avoid sync if difference is below sync_refresh_period
508 		 * and below the half timeout.
509 		 */
510 		if (abs(diff) < min_t(long, sync_refresh_period, min_diff)) {
511 			int retries = orig & 3;
512 
513 			if (retries >= sysctl_sync_retries(ipvs))
514 				return 0;
515 			if (time_before(now, orig - cp->timeout +
516 					(sync_refresh_period >> 3)))
517 				return 0;
518 			n |= retries + 1;
519 		}
520 	}
521 	sync_period = sysctl_sync_period(ipvs);
522 	if (sync_period > 0) {
523 		if (!(cp->flags & IP_VS_CONN_F_TEMPLATE) &&
524 		    pkts % sync_period != sysctl_sync_threshold(ipvs))
525 			return 0;
526 	} else if (!sync_refresh_period &&
527 		   pkts != sysctl_sync_threshold(ipvs))
528 		return 0;
529 
530 set:
531 	cp->old_state = cp->state;
532 	n = cmpxchg(&cp->sync_endtime, orig, n);
533 	return n == orig || force;
534 }
535 
536 /*
537  *      Version 0 , could be switched in by sys_ctl.
538  *      Add an ip_vs_conn information into the current sync_buff.
539  */
ip_vs_sync_conn_v0(struct netns_ipvs * ipvs,struct ip_vs_conn * cp,int pkts)540 static void ip_vs_sync_conn_v0(struct netns_ipvs *ipvs, struct ip_vs_conn *cp,
541 			       int pkts)
542 {
543 	struct ip_vs_sync_mesg_v0 *m;
544 	struct ip_vs_sync_conn_v0 *s;
545 	struct ip_vs_sync_buff *buff;
546 	struct ipvs_master_sync_state *ms;
547 	int id;
548 	unsigned int len;
549 
550 	if (unlikely(cp->af != AF_INET))
551 		return;
552 	/* Do not sync ONE PACKET */
553 	if (cp->flags & IP_VS_CONN_F_ONE_PACKET)
554 		return;
555 
556 	if (!ip_vs_sync_conn_needed(ipvs, cp, pkts))
557 		return;
558 
559 	spin_lock_bh(&ipvs->sync_buff_lock);
560 	if (!(ipvs->sync_state & IP_VS_STATE_MASTER)) {
561 		spin_unlock_bh(&ipvs->sync_buff_lock);
562 		return;
563 	}
564 
565 	id = select_master_thread_id(ipvs, cp);
566 	ms = &ipvs->ms[id];
567 	buff = ms->sync_buff;
568 	len = (cp->flags & IP_VS_CONN_F_SEQ_MASK) ? FULL_CONN_SIZE :
569 		SIMPLE_CONN_SIZE;
570 	if (buff) {
571 		m = (struct ip_vs_sync_mesg_v0 *) buff->mesg;
572 		/* Send buffer if it is for v1 */
573 		if (buff->head + len > buff->end || !m->nr_conns) {
574 			sb_queue_tail(ipvs, ms);
575 			ms->sync_buff = NULL;
576 			buff = NULL;
577 		}
578 	}
579 	if (!buff) {
580 		buff = ip_vs_sync_buff_create_v0(ipvs, len);
581 		if (!buff) {
582 			spin_unlock_bh(&ipvs->sync_buff_lock);
583 			pr_err("ip_vs_sync_buff_create failed.\n");
584 			return;
585 		}
586 		ms->sync_buff = buff;
587 	}
588 
589 	m = (struct ip_vs_sync_mesg_v0 *) buff->mesg;
590 	s = (struct ip_vs_sync_conn_v0 *) buff->head;
591 
592 	/* copy members */
593 	s->reserved = 0;
594 	s->protocol = cp->protocol;
595 	s->cport = cp->cport;
596 	s->vport = cp->vport;
597 	s->dport = cp->dport;
598 	s->caddr = cp->caddr.ip;
599 	s->vaddr = cp->vaddr.ip;
600 	s->daddr = cp->daddr.ip;
601 	s->flags = htons(cp->flags & ~IP_VS_CONN_F_HASHED);
602 	s->state = htons(cp->state);
603 	if (cp->flags & IP_VS_CONN_F_SEQ_MASK) {
604 		struct ip_vs_sync_conn_options *opt =
605 			(struct ip_vs_sync_conn_options *)&s[1];
606 		memcpy(opt, &cp->sync_conn_opt, sizeof(*opt));
607 	}
608 
609 	m->nr_conns++;
610 	m->size = htons(ntohs(m->size) + len);
611 	buff->head += len;
612 	spin_unlock_bh(&ipvs->sync_buff_lock);
613 
614 	/* synchronize its controller if it has */
615 	cp = cp->control;
616 	if (cp) {
617 		if (cp->flags & IP_VS_CONN_F_TEMPLATE)
618 			pkts = atomic_inc_return(&cp->in_pkts);
619 		else
620 			pkts = sysctl_sync_threshold(ipvs);
621 		ip_vs_sync_conn(ipvs, cp, pkts);
622 	}
623 }
624 
625 /*
626  *      Add an ip_vs_conn information into the current sync_buff.
627  *      Called by ip_vs_in.
628  *      Sending Version 1 messages
629  */
ip_vs_sync_conn(struct netns_ipvs * ipvs,struct ip_vs_conn * cp,int pkts)630 void ip_vs_sync_conn(struct netns_ipvs *ipvs, struct ip_vs_conn *cp, int pkts)
631 {
632 	struct ip_vs_sync_mesg *m;
633 	union ip_vs_sync_conn *s;
634 	struct ip_vs_sync_buff *buff;
635 	struct ipvs_master_sync_state *ms;
636 	int id;
637 	__u8 *p;
638 	unsigned int len, pe_name_len, pad;
639 
640 	/* Handle old version of the protocol */
641 	if (sysctl_sync_ver(ipvs) == 0) {
642 		ip_vs_sync_conn_v0(ipvs, cp, pkts);
643 		return;
644 	}
645 	/* Do not sync ONE PACKET */
646 	if (cp->flags & IP_VS_CONN_F_ONE_PACKET)
647 		goto control;
648 sloop:
649 	if (!ip_vs_sync_conn_needed(ipvs, cp, pkts))
650 		goto control;
651 
652 	/* Sanity checks */
653 	pe_name_len = 0;
654 	if (cp->pe_data_len) {
655 		if (!cp->pe_data || !cp->dest) {
656 			IP_VS_ERR_RL("SYNC, connection pe_data invalid\n");
657 			return;
658 		}
659 		pe_name_len = strnlen(cp->pe->name, IP_VS_PENAME_MAXLEN);
660 	}
661 
662 	spin_lock_bh(&ipvs->sync_buff_lock);
663 	if (!(ipvs->sync_state & IP_VS_STATE_MASTER)) {
664 		spin_unlock_bh(&ipvs->sync_buff_lock);
665 		return;
666 	}
667 
668 	id = select_master_thread_id(ipvs, cp);
669 	ms = &ipvs->ms[id];
670 
671 #ifdef CONFIG_IP_VS_IPV6
672 	if (cp->af == AF_INET6)
673 		len = sizeof(struct ip_vs_sync_v6);
674 	else
675 #endif
676 		len = sizeof(struct ip_vs_sync_v4);
677 
678 	if (cp->flags & IP_VS_CONN_F_SEQ_MASK)
679 		len += sizeof(struct ip_vs_sync_conn_options) + 2;
680 
681 	if (cp->pe_data_len)
682 		len += cp->pe_data_len + 2;	/* + Param hdr field */
683 	if (pe_name_len)
684 		len += pe_name_len + 2;
685 
686 	/* check if there is a space for this one  */
687 	pad = 0;
688 	buff = ms->sync_buff;
689 	if (buff) {
690 		m = buff->mesg;
691 		pad = (4 - (size_t) buff->head) & 3;
692 		/* Send buffer if it is for v0 */
693 		if (buff->head + len + pad > buff->end || m->reserved) {
694 			sb_queue_tail(ipvs, ms);
695 			ms->sync_buff = NULL;
696 			buff = NULL;
697 			pad = 0;
698 		}
699 	}
700 
701 	if (!buff) {
702 		buff = ip_vs_sync_buff_create(ipvs, len);
703 		if (!buff) {
704 			spin_unlock_bh(&ipvs->sync_buff_lock);
705 			pr_err("ip_vs_sync_buff_create failed.\n");
706 			return;
707 		}
708 		ms->sync_buff = buff;
709 		m = buff->mesg;
710 	}
711 
712 	p = buff->head;
713 	buff->head += pad + len;
714 	m->size = htons(ntohs(m->size) + pad + len);
715 	/* Add ev. padding from prev. sync_conn */
716 	while (pad--)
717 		*(p++) = 0;
718 
719 	s = (union ip_vs_sync_conn *)p;
720 
721 	/* Set message type  & copy members */
722 	s->v4.type = (cp->af == AF_INET6 ? STYPE_F_INET6 : 0);
723 	s->v4.ver_size = htons(len & SVER_MASK);	/* Version 0 */
724 	s->v4.flags = htonl(cp->flags & ~IP_VS_CONN_F_HASHED);
725 	s->v4.state = htons(cp->state);
726 	s->v4.protocol = cp->protocol;
727 	s->v4.cport = cp->cport;
728 	s->v4.vport = cp->vport;
729 	s->v4.dport = cp->dport;
730 	s->v4.fwmark = htonl(cp->fwmark);
731 	s->v4.timeout = htonl(cp->timeout / HZ);
732 	m->nr_conns++;
733 
734 #ifdef CONFIG_IP_VS_IPV6
735 	if (cp->af == AF_INET6) {
736 		p += sizeof(struct ip_vs_sync_v6);
737 		s->v6.caddr = cp->caddr.in6;
738 		s->v6.vaddr = cp->vaddr.in6;
739 		s->v6.daddr = cp->daddr.in6;
740 	} else
741 #endif
742 	{
743 		p += sizeof(struct ip_vs_sync_v4);	/* options ptr */
744 		s->v4.caddr = cp->caddr.ip;
745 		s->v4.vaddr = cp->vaddr.ip;
746 		s->v4.daddr = cp->daddr.ip;
747 	}
748 	if (cp->flags & IP_VS_CONN_F_SEQ_MASK) {
749 		*(p++) = IPVS_OPT_SEQ_DATA;
750 		*(p++) = sizeof(struct ip_vs_sync_conn_options);
751 		hton_seq((struct ip_vs_seq *)p, &cp->in_seq);
752 		p += sizeof(struct ip_vs_seq);
753 		hton_seq((struct ip_vs_seq *)p, &cp->out_seq);
754 		p += sizeof(struct ip_vs_seq);
755 	}
756 	/* Handle pe data */
757 	if (cp->pe_data_len && cp->pe_data) {
758 		*(p++) = IPVS_OPT_PE_DATA;
759 		*(p++) = cp->pe_data_len;
760 		memcpy(p, cp->pe_data, cp->pe_data_len);
761 		p += cp->pe_data_len;
762 		if (pe_name_len) {
763 			/* Add PE_NAME */
764 			*(p++) = IPVS_OPT_PE_NAME;
765 			*(p++) = pe_name_len;
766 			memcpy(p, cp->pe->name, pe_name_len);
767 			p += pe_name_len;
768 		}
769 	}
770 
771 	spin_unlock_bh(&ipvs->sync_buff_lock);
772 
773 control:
774 	/* synchronize its controller if it has */
775 	cp = cp->control;
776 	if (!cp)
777 		return;
778 	if (cp->flags & IP_VS_CONN_F_TEMPLATE)
779 		pkts = atomic_inc_return(&cp->in_pkts);
780 	else
781 		pkts = sysctl_sync_threshold(ipvs);
782 	goto sloop;
783 }
784 
785 /*
786  *  fill_param used by version 1
787  */
788 static inline int
ip_vs_conn_fill_param_sync(struct netns_ipvs * ipvs,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)789 ip_vs_conn_fill_param_sync(struct netns_ipvs *ipvs, int af, union ip_vs_sync_conn *sc,
790 			   struct ip_vs_conn_param *p,
791 			   __u8 *pe_data, unsigned int pe_data_len,
792 			   __u8 *pe_name, unsigned int pe_name_len)
793 {
794 #ifdef CONFIG_IP_VS_IPV6
795 	if (af == AF_INET6)
796 		ip_vs_conn_fill_param(ipvs, af, sc->v6.protocol,
797 				      (const union nf_inet_addr *)&sc->v6.caddr,
798 				      sc->v6.cport,
799 				      (const union nf_inet_addr *)&sc->v6.vaddr,
800 				      sc->v6.vport, p);
801 	else
802 #endif
803 		ip_vs_conn_fill_param(ipvs, af, sc->v4.protocol,
804 				      (const union nf_inet_addr *)&sc->v4.caddr,
805 				      sc->v4.cport,
806 				      (const union nf_inet_addr *)&sc->v4.vaddr,
807 				      sc->v4.vport, p);
808 	/* Handle pe data */
809 	if (pe_data_len) {
810 		if (pe_name_len) {
811 			char buff[IP_VS_PENAME_MAXLEN+1];
812 
813 			memcpy(buff, pe_name, pe_name_len);
814 			buff[pe_name_len]=0;
815 			p->pe = __ip_vs_pe_getbyname(buff);
816 			if (!p->pe) {
817 				IP_VS_DBG(3, "BACKUP, no %s engine found/loaded\n",
818 					     buff);
819 				return 1;
820 			}
821 		} else {
822 			IP_VS_ERR_RL("BACKUP, Invalid PE parameters\n");
823 			return 1;
824 		}
825 
826 		p->pe_data = kmemdup(pe_data, pe_data_len, GFP_ATOMIC);
827 		if (!p->pe_data) {
828 			module_put(p->pe->module);
829 			return -ENOMEM;
830 		}
831 		p->pe_data_len = pe_data_len;
832 	}
833 	return 0;
834 }
835 
836 /*
837  *  Connection Add / Update.
838  *  Common for version 0 and 1 reception of backup sync_conns.
839  *  Param: ...
840  *         timeout is in sec.
841  */
ip_vs_proc_conn(struct netns_ipvs * ipvs,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)842 static void ip_vs_proc_conn(struct netns_ipvs *ipvs, struct ip_vs_conn_param *param,
843 			    unsigned int flags, unsigned int state,
844 			    unsigned int protocol, unsigned int type,
845 			    const union nf_inet_addr *daddr, __be16 dport,
846 			    unsigned long timeout, __u32 fwmark,
847 			    struct ip_vs_sync_conn_options *opt)
848 {
849 	struct ip_vs_dest *dest;
850 	struct ip_vs_conn *cp;
851 
852 	if (!(flags & IP_VS_CONN_F_TEMPLATE)) {
853 		cp = ip_vs_conn_in_get(param);
854 		if (cp && ((cp->dport != dport) ||
855 			   !ip_vs_addr_equal(cp->daf, &cp->daddr, daddr))) {
856 			if (!(flags & IP_VS_CONN_F_INACTIVE)) {
857 				ip_vs_conn_expire_now(cp);
858 				__ip_vs_conn_put(cp);
859 				cp = NULL;
860 			} else {
861 				/* This is the expiration message for the
862 				 * connection that was already replaced, so we
863 				 * just ignore it.
864 				 */
865 				__ip_vs_conn_put(cp);
866 				kfree(param->pe_data);
867 				return;
868 			}
869 		}
870 	} else {
871 		cp = ip_vs_ct_in_get(param);
872 	}
873 
874 	if (cp) {
875 		/* Free pe_data */
876 		kfree(param->pe_data);
877 
878 		dest = cp->dest;
879 		spin_lock_bh(&cp->lock);
880 		if ((cp->flags ^ flags) & IP_VS_CONN_F_INACTIVE &&
881 		    !(flags & IP_VS_CONN_F_TEMPLATE) && dest) {
882 			if (flags & IP_VS_CONN_F_INACTIVE) {
883 				atomic_dec(&dest->activeconns);
884 				atomic_inc(&dest->inactconns);
885 			} else {
886 				atomic_inc(&dest->activeconns);
887 				atomic_dec(&dest->inactconns);
888 			}
889 		}
890 		flags &= IP_VS_CONN_F_BACKUP_UPD_MASK;
891 		flags |= cp->flags & ~IP_VS_CONN_F_BACKUP_UPD_MASK;
892 		cp->flags = flags;
893 		spin_unlock_bh(&cp->lock);
894 		if (!dest)
895 			ip_vs_try_bind_dest(cp);
896 	} else {
897 		/*
898 		 * Find the appropriate destination for the connection.
899 		 * If it is not found the connection will remain unbound
900 		 * but still handled.
901 		 */
902 		rcu_read_lock();
903 		/* This function is only invoked by the synchronization
904 		 * code. We do not currently support heterogeneous pools
905 		 * with synchronization, so we can make the assumption that
906 		 * the svc_af is the same as the dest_af
907 		 */
908 		dest = ip_vs_find_dest(ipvs, type, type, daddr, dport,
909 				       param->vaddr, param->vport, protocol,
910 				       fwmark, flags);
911 
912 		cp = ip_vs_conn_new(param, type, daddr, dport, flags, dest,
913 				    fwmark);
914 		rcu_read_unlock();
915 		if (!cp) {
916 			kfree(param->pe_data);
917 			IP_VS_DBG(2, "BACKUP, add new conn. failed\n");
918 			return;
919 		}
920 		if (!(flags & IP_VS_CONN_F_TEMPLATE))
921 			kfree(param->pe_data);
922 	}
923 
924 	if (opt) {
925 		cp->in_seq = opt->in_seq;
926 		cp->out_seq = opt->out_seq;
927 	}
928 	atomic_set(&cp->in_pkts, sysctl_sync_threshold(ipvs));
929 	cp->state = state;
930 	cp->old_state = cp->state;
931 	/*
932 	 * For Ver 0 messages style
933 	 *  - Not possible to recover the right timeout for templates
934 	 *  - can not find the right fwmark
935 	 *    virtual service. If needed, we can do it for
936 	 *    non-fwmark persistent services.
937 	 * Ver 1 messages style.
938 	 *  - No problem.
939 	 */
940 	if (timeout) {
941 		if (timeout > MAX_SCHEDULE_TIMEOUT / HZ)
942 			timeout = MAX_SCHEDULE_TIMEOUT / HZ;
943 		cp->timeout = timeout*HZ;
944 	} else {
945 		struct ip_vs_proto_data *pd;
946 
947 		pd = ip_vs_proto_data_get(ipvs, protocol);
948 		if (!(flags & IP_VS_CONN_F_TEMPLATE) && pd && pd->timeout_table)
949 			cp->timeout = pd->timeout_table[state];
950 		else
951 			cp->timeout = (3*60*HZ);
952 	}
953 	ip_vs_conn_put(cp);
954 }
955 
956 /*
957  *  Process received multicast message for Version 0
958  */
ip_vs_process_message_v0(struct netns_ipvs * ipvs,const char * buffer,const size_t buflen)959 static void ip_vs_process_message_v0(struct netns_ipvs *ipvs, const char *buffer,
960 				     const size_t buflen)
961 {
962 	struct ip_vs_sync_mesg_v0 *m = (struct ip_vs_sync_mesg_v0 *)buffer;
963 	struct ip_vs_sync_conn_v0 *s;
964 	struct ip_vs_sync_conn_options *opt;
965 	struct ip_vs_protocol *pp;
966 	struct ip_vs_conn_param param;
967 	char *p;
968 	int i;
969 
970 	p = (char *)buffer + sizeof(struct ip_vs_sync_mesg_v0);
971 	for (i=0; i<m->nr_conns; i++) {
972 		unsigned int flags, state;
973 
974 		if (p + SIMPLE_CONN_SIZE > buffer+buflen) {
975 			IP_VS_ERR_RL("BACKUP v0, bogus conn\n");
976 			return;
977 		}
978 		s = (struct ip_vs_sync_conn_v0 *) p;
979 		flags = ntohs(s->flags) | IP_VS_CONN_F_SYNC;
980 		flags &= ~IP_VS_CONN_F_HASHED;
981 		if (flags & IP_VS_CONN_F_SEQ_MASK) {
982 			opt = (struct ip_vs_sync_conn_options *)&s[1];
983 			p += FULL_CONN_SIZE;
984 			if (p > buffer+buflen) {
985 				IP_VS_ERR_RL("BACKUP v0, Dropping buffer bogus conn options\n");
986 				return;
987 			}
988 		} else {
989 			opt = NULL;
990 			p += SIMPLE_CONN_SIZE;
991 		}
992 
993 		state = ntohs(s->state);
994 		if (!(flags & IP_VS_CONN_F_TEMPLATE)) {
995 			pp = ip_vs_proto_get(s->protocol);
996 			if (!pp) {
997 				IP_VS_DBG(2, "BACKUP v0, Unsupported protocol %u\n",
998 					s->protocol);
999 				continue;
1000 			}
1001 			if (state >= pp->num_states) {
1002 				IP_VS_DBG(2, "BACKUP v0, Invalid %s state %u\n",
1003 					pp->name, state);
1004 				continue;
1005 			}
1006 		} else {
1007 			if (state >= IP_VS_CTPL_S_LAST)
1008 				IP_VS_DBG(7, "BACKUP v0, Invalid tpl state %u\n",
1009 					  state);
1010 		}
1011 
1012 		ip_vs_conn_fill_param(ipvs, AF_INET, s->protocol,
1013 				      (const union nf_inet_addr *)&s->caddr,
1014 				      s->cport,
1015 				      (const union nf_inet_addr *)&s->vaddr,
1016 				      s->vport, &param);
1017 
1018 		/* Send timeout as Zero */
1019 		ip_vs_proc_conn(ipvs, &param, flags, state, s->protocol, AF_INET,
1020 				(union nf_inet_addr *)&s->daddr, s->dport,
1021 				0, 0, opt);
1022 	}
1023 }
1024 
1025 /*
1026  * Handle options
1027  */
ip_vs_proc_seqopt(__u8 * p,unsigned int plen,__u32 * opt_flags,struct ip_vs_sync_conn_options * opt)1028 static inline int ip_vs_proc_seqopt(__u8 *p, unsigned int plen,
1029 				    __u32 *opt_flags,
1030 				    struct ip_vs_sync_conn_options *opt)
1031 {
1032 	struct ip_vs_sync_conn_options *topt;
1033 
1034 	topt = (struct ip_vs_sync_conn_options *)p;
1035 
1036 	if (plen != sizeof(struct ip_vs_sync_conn_options)) {
1037 		IP_VS_DBG(2, "BACKUP, bogus conn options length\n");
1038 		return -EINVAL;
1039 	}
1040 	if (*opt_flags & IPVS_OPT_F_SEQ_DATA) {
1041 		IP_VS_DBG(2, "BACKUP, conn options found twice\n");
1042 		return -EINVAL;
1043 	}
1044 	ntoh_seq(&topt->in_seq, &opt->in_seq);
1045 	ntoh_seq(&topt->out_seq, &opt->out_seq);
1046 	*opt_flags |= IPVS_OPT_F_SEQ_DATA;
1047 	return 0;
1048 }
1049 
ip_vs_proc_str(__u8 * p,unsigned int plen,unsigned int * data_len,__u8 ** data,unsigned int maxlen,__u32 * opt_flags,__u32 flag)1050 static int ip_vs_proc_str(__u8 *p, unsigned int plen, unsigned int *data_len,
1051 			  __u8 **data, unsigned int maxlen,
1052 			  __u32 *opt_flags, __u32 flag)
1053 {
1054 	if (plen > maxlen) {
1055 		IP_VS_DBG(2, "BACKUP, bogus par.data len > %d\n", maxlen);
1056 		return -EINVAL;
1057 	}
1058 	if (*opt_flags & flag) {
1059 		IP_VS_DBG(2, "BACKUP, Par.data found twice 0x%x\n", flag);
1060 		return -EINVAL;
1061 	}
1062 	*data_len = plen;
1063 	*data = p;
1064 	*opt_flags |= flag;
1065 	return 0;
1066 }
1067 /*
1068  *   Process a Version 1 sync. connection
1069  */
ip_vs_proc_sync_conn(struct netns_ipvs * ipvs,__u8 * p,__u8 * msg_end)1070 static inline int ip_vs_proc_sync_conn(struct netns_ipvs *ipvs, __u8 *p, __u8 *msg_end)
1071 {
1072 	struct ip_vs_sync_conn_options opt;
1073 	union  ip_vs_sync_conn *s;
1074 	struct ip_vs_protocol *pp;
1075 	struct ip_vs_conn_param param;
1076 	__u32 flags;
1077 	unsigned int af, state, pe_data_len=0, pe_name_len=0;
1078 	__u8 *pe_data=NULL, *pe_name=NULL;
1079 	__u32 opt_flags=0;
1080 	int retc=0;
1081 
1082 	s = (union ip_vs_sync_conn *) p;
1083 
1084 	if (s->v6.type & STYPE_F_INET6) {
1085 #ifdef CONFIG_IP_VS_IPV6
1086 		af = AF_INET6;
1087 		p += sizeof(struct ip_vs_sync_v6);
1088 #else
1089 		IP_VS_DBG(3,"BACKUP, IPv6 msg received, and IPVS is not compiled for IPv6\n");
1090 		retc = 10;
1091 		goto out;
1092 #endif
1093 	} else if (!s->v4.type) {
1094 		af = AF_INET;
1095 		p += sizeof(struct ip_vs_sync_v4);
1096 	} else {
1097 		return -10;
1098 	}
1099 	if (p > msg_end)
1100 		return -20;
1101 
1102 	/* Process optional params check Type & Len. */
1103 	while (p < msg_end) {
1104 		int ptype;
1105 		int plen;
1106 
1107 		if (p+2 > msg_end)
1108 			return -30;
1109 		ptype = *(p++);
1110 		plen  = *(p++);
1111 
1112 		if (!plen || ((p + plen) > msg_end))
1113 			return -40;
1114 		/* Handle seq option  p = param data */
1115 		switch (ptype & ~IPVS_OPT_F_PARAM) {
1116 		case IPVS_OPT_SEQ_DATA:
1117 			if (ip_vs_proc_seqopt(p, plen, &opt_flags, &opt))
1118 				return -50;
1119 			break;
1120 
1121 		case IPVS_OPT_PE_DATA:
1122 			if (ip_vs_proc_str(p, plen, &pe_data_len, &pe_data,
1123 					   IP_VS_PEDATA_MAXLEN, &opt_flags,
1124 					   IPVS_OPT_F_PE_DATA))
1125 				return -60;
1126 			break;
1127 
1128 		case IPVS_OPT_PE_NAME:
1129 			if (ip_vs_proc_str(p, plen,&pe_name_len, &pe_name,
1130 					   IP_VS_PENAME_MAXLEN, &opt_flags,
1131 					   IPVS_OPT_F_PE_NAME))
1132 				return -70;
1133 			break;
1134 
1135 		default:
1136 			/* Param data mandatory ? */
1137 			if (!(ptype & IPVS_OPT_F_PARAM)) {
1138 				IP_VS_DBG(3, "BACKUP, Unknown mandatory param %d found\n",
1139 					  ptype & ~IPVS_OPT_F_PARAM);
1140 				retc = 20;
1141 				goto out;
1142 			}
1143 		}
1144 		p += plen;  /* Next option */
1145 	}
1146 
1147 	/* Get flags and Mask off unsupported */
1148 	flags  = ntohl(s->v4.flags) & IP_VS_CONN_F_BACKUP_MASK;
1149 	flags |= IP_VS_CONN_F_SYNC;
1150 	state = ntohs(s->v4.state);
1151 
1152 	if (!(flags & IP_VS_CONN_F_TEMPLATE)) {
1153 		pp = ip_vs_proto_get(s->v4.protocol);
1154 		if (!pp) {
1155 			IP_VS_DBG(3,"BACKUP, Unsupported protocol %u\n",
1156 				s->v4.protocol);
1157 			retc = 30;
1158 			goto out;
1159 		}
1160 		if (state >= pp->num_states) {
1161 			IP_VS_DBG(3, "BACKUP, Invalid %s state %u\n",
1162 				pp->name, state);
1163 			retc = 40;
1164 			goto out;
1165 		}
1166 	} else {
1167 		if (state >= IP_VS_CTPL_S_LAST)
1168 			IP_VS_DBG(7, "BACKUP, Invalid tpl state %u\n",
1169 				  state);
1170 	}
1171 	if (ip_vs_conn_fill_param_sync(ipvs, af, s, &param, pe_data,
1172 				       pe_data_len, pe_name, pe_name_len)) {
1173 		retc = 50;
1174 		goto out;
1175 	}
1176 	/* If only IPv4, just silent skip IPv6 */
1177 	if (af == AF_INET)
1178 		ip_vs_proc_conn(ipvs, &param, flags, state, s->v4.protocol, af,
1179 				(union nf_inet_addr *)&s->v4.daddr, s->v4.dport,
1180 				ntohl(s->v4.timeout), ntohl(s->v4.fwmark),
1181 				(opt_flags & IPVS_OPT_F_SEQ_DATA ? &opt : NULL)
1182 				);
1183 #ifdef CONFIG_IP_VS_IPV6
1184 	else
1185 		ip_vs_proc_conn(ipvs, &param, flags, state, s->v6.protocol, af,
1186 				(union nf_inet_addr *)&s->v6.daddr, s->v6.dport,
1187 				ntohl(s->v6.timeout), ntohl(s->v6.fwmark),
1188 				(opt_flags & IPVS_OPT_F_SEQ_DATA ? &opt : NULL)
1189 				);
1190 #endif
1191 	ip_vs_pe_put(param.pe);
1192 	return 0;
1193 	/* Error exit */
1194 out:
1195 	IP_VS_DBG(2, "BACKUP, Single msg dropped err:%d\n", retc);
1196 	return retc;
1197 
1198 }
1199 /*
1200  *      Process received multicast message and create the corresponding
1201  *      ip_vs_conn entries.
1202  *      Handles Version 0 & 1
1203  */
ip_vs_process_message(struct netns_ipvs * ipvs,__u8 * buffer,const size_t buflen)1204 static void ip_vs_process_message(struct netns_ipvs *ipvs, __u8 *buffer,
1205 				  const size_t buflen)
1206 {
1207 	struct ip_vs_sync_mesg *m2 = (struct ip_vs_sync_mesg *)buffer;
1208 	__u8 *p, *msg_end;
1209 	int i, nr_conns;
1210 
1211 	if (buflen < sizeof(struct ip_vs_sync_mesg_v0)) {
1212 		IP_VS_DBG(2, "BACKUP, message header too short\n");
1213 		return;
1214 	}
1215 
1216 	if (buflen != ntohs(m2->size)) {
1217 		IP_VS_DBG(2, "BACKUP, bogus message size\n");
1218 		return;
1219 	}
1220 	/* SyncID sanity check */
1221 	if (ipvs->bcfg.syncid != 0 && m2->syncid != ipvs->bcfg.syncid) {
1222 		IP_VS_DBG(7, "BACKUP, Ignoring syncid = %d\n", m2->syncid);
1223 		return;
1224 	}
1225 	/* Handle version 1  message */
1226 	if ((m2->version == SYNC_PROTO_VER) && (m2->reserved == 0)
1227 	    && (m2->spare == 0)) {
1228 
1229 		msg_end = buffer + sizeof(struct ip_vs_sync_mesg);
1230 		nr_conns = m2->nr_conns;
1231 
1232 		for (i=0; i<nr_conns; i++) {
1233 			union ip_vs_sync_conn *s;
1234 			unsigned int size;
1235 			int retc;
1236 
1237 			p = msg_end;
1238 			if (p + sizeof(s->v4) > buffer+buflen) {
1239 				IP_VS_ERR_RL("BACKUP, Dropping buffer, too small\n");
1240 				return;
1241 			}
1242 			s = (union ip_vs_sync_conn *)p;
1243 			size = ntohs(s->v4.ver_size) & SVER_MASK;
1244 			msg_end = p + size;
1245 			/* Basic sanity checks */
1246 			if (msg_end  > buffer+buflen) {
1247 				IP_VS_ERR_RL("BACKUP, Dropping buffer, msg > buffer\n");
1248 				return;
1249 			}
1250 			if (ntohs(s->v4.ver_size) >> SVER_SHIFT) {
1251 				IP_VS_ERR_RL("BACKUP, Dropping buffer, Unknown version %d\n",
1252 					      ntohs(s->v4.ver_size) >> SVER_SHIFT);
1253 				return;
1254 			}
1255 			/* Process a single sync_conn */
1256 			retc = ip_vs_proc_sync_conn(ipvs, p, msg_end);
1257 			if (retc < 0) {
1258 				IP_VS_ERR_RL("BACKUP, Dropping buffer, Err: %d in decoding\n",
1259 					     retc);
1260 				return;
1261 			}
1262 			/* Make sure we have 32 bit alignment */
1263 			msg_end = p + ((size + 3) & ~3);
1264 		}
1265 	} else {
1266 		/* Old type of message */
1267 		ip_vs_process_message_v0(ipvs, buffer, buflen);
1268 		return;
1269 	}
1270 }
1271 
1272 
1273 /*
1274  *      Setup sndbuf (mode=1) or rcvbuf (mode=0)
1275  */
set_sock_size(struct sock * sk,int mode,int val)1276 static void set_sock_size(struct sock *sk, int mode, int val)
1277 {
1278 	/* setsockopt(sock, SOL_SOCKET, SO_SNDBUF, &val, sizeof(val)); */
1279 	/* setsockopt(sock, SOL_SOCKET, SO_RCVBUF, &val, sizeof(val)); */
1280 	lock_sock(sk);
1281 	if (mode) {
1282 		val = clamp_t(int, val, (SOCK_MIN_SNDBUF + 1) / 2,
1283 			      READ_ONCE(sysctl_wmem_max));
1284 		sk->sk_sndbuf = val * 2;
1285 		sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
1286 	} else {
1287 		val = clamp_t(int, val, (SOCK_MIN_RCVBUF + 1) / 2,
1288 			      READ_ONCE(sysctl_rmem_max));
1289 		sk->sk_rcvbuf = val * 2;
1290 		sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
1291 	}
1292 	release_sock(sk);
1293 }
1294 
1295 /*
1296  *      Setup loopback of outgoing multicasts on a sending socket
1297  */
set_mcast_loop(struct sock * sk,u_char loop)1298 static void set_mcast_loop(struct sock *sk, u_char loop)
1299 {
1300 	/* setsockopt(sock, SOL_IP, IP_MULTICAST_LOOP, &loop, sizeof(loop)); */
1301 	lock_sock(sk);
1302 	inet_assign_bit(MC_LOOP, sk, loop);
1303 #ifdef CONFIG_IP_VS_IPV6
1304 	if (sk->sk_family == AF_INET6) {
1305 		struct ipv6_pinfo *np = inet6_sk(sk);
1306 
1307 		/* IPV6_MULTICAST_LOOP */
1308 		np->mc_loop = loop ? 1 : 0;
1309 	}
1310 #endif
1311 	release_sock(sk);
1312 }
1313 
1314 /*
1315  *      Specify TTL for outgoing multicasts on a sending socket
1316  */
set_mcast_ttl(struct sock * sk,u_char ttl)1317 static void set_mcast_ttl(struct sock *sk, u_char ttl)
1318 {
1319 	struct inet_sock *inet = inet_sk(sk);
1320 
1321 	/* setsockopt(sock, SOL_IP, IP_MULTICAST_TTL, &ttl, sizeof(ttl)); */
1322 	lock_sock(sk);
1323 	inet->mc_ttl = ttl;
1324 #ifdef CONFIG_IP_VS_IPV6
1325 	if (sk->sk_family == AF_INET6) {
1326 		struct ipv6_pinfo *np = inet6_sk(sk);
1327 
1328 		/* IPV6_MULTICAST_HOPS */
1329 		np->mcast_hops = ttl;
1330 	}
1331 #endif
1332 	release_sock(sk);
1333 }
1334 
1335 /* Control fragmentation of messages */
set_mcast_pmtudisc(struct sock * sk,int val)1336 static void set_mcast_pmtudisc(struct sock *sk, int val)
1337 {
1338 	struct inet_sock *inet = inet_sk(sk);
1339 
1340 	/* setsockopt(sock, SOL_IP, IP_MTU_DISCOVER, &val, sizeof(val)); */
1341 	lock_sock(sk);
1342 	inet->pmtudisc = val;
1343 #ifdef CONFIG_IP_VS_IPV6
1344 	if (sk->sk_family == AF_INET6) {
1345 		struct ipv6_pinfo *np = inet6_sk(sk);
1346 
1347 		/* IPV6_MTU_DISCOVER */
1348 		np->pmtudisc = val;
1349 	}
1350 #endif
1351 	release_sock(sk);
1352 }
1353 
1354 /*
1355  *      Specifiy default interface for outgoing multicasts
1356  */
set_mcast_if(struct sock * sk,struct net_device * dev)1357 static int set_mcast_if(struct sock *sk, struct net_device *dev)
1358 {
1359 	struct inet_sock *inet = inet_sk(sk);
1360 
1361 	if (sk->sk_bound_dev_if && dev->ifindex != sk->sk_bound_dev_if)
1362 		return -EINVAL;
1363 
1364 	lock_sock(sk);
1365 	inet->mc_index = dev->ifindex;
1366 	/*  inet->mc_addr  = 0; */
1367 #ifdef CONFIG_IP_VS_IPV6
1368 	if (sk->sk_family == AF_INET6) {
1369 		struct ipv6_pinfo *np = inet6_sk(sk);
1370 
1371 		/* IPV6_MULTICAST_IF */
1372 		np->mcast_oif = dev->ifindex;
1373 	}
1374 #endif
1375 	release_sock(sk);
1376 
1377 	return 0;
1378 }
1379 
1380 
1381 /*
1382  *      Join a multicast group.
1383  *      the group is specified by a class D multicast address 224.0.0.0/8
1384  *      in the in_addr structure passed in as a parameter.
1385  */
1386 static int
join_mcast_group(struct sock * sk,struct in_addr * addr,struct net_device * dev)1387 join_mcast_group(struct sock *sk, struct in_addr *addr, struct net_device *dev)
1388 {
1389 	struct ip_mreqn mreq;
1390 	int ret;
1391 
1392 	memset(&mreq, 0, sizeof(mreq));
1393 	memcpy(&mreq.imr_multiaddr, addr, sizeof(struct in_addr));
1394 
1395 	if (sk->sk_bound_dev_if && dev->ifindex != sk->sk_bound_dev_if)
1396 		return -EINVAL;
1397 
1398 	mreq.imr_ifindex = dev->ifindex;
1399 
1400 	lock_sock(sk);
1401 	ret = ip_mc_join_group(sk, &mreq);
1402 	release_sock(sk);
1403 
1404 	return ret;
1405 }
1406 
1407 #ifdef CONFIG_IP_VS_IPV6
join_mcast_group6(struct sock * sk,struct in6_addr * addr,struct net_device * dev)1408 static int join_mcast_group6(struct sock *sk, struct in6_addr *addr,
1409 			     struct net_device *dev)
1410 {
1411 	int ret;
1412 
1413 	if (sk->sk_bound_dev_if && dev->ifindex != sk->sk_bound_dev_if)
1414 		return -EINVAL;
1415 
1416 	lock_sock(sk);
1417 	ret = ipv6_sock_mc_join(sk, dev->ifindex, addr);
1418 	release_sock(sk);
1419 
1420 	return ret;
1421 }
1422 #endif
1423 
bind_mcastif_addr(struct socket * sock,struct net_device * dev)1424 static int bind_mcastif_addr(struct socket *sock, struct net_device *dev)
1425 {
1426 	__be32 addr;
1427 	struct sockaddr_in sin;
1428 
1429 	addr = inet_select_addr(dev, 0, RT_SCOPE_UNIVERSE);
1430 	if (!addr)
1431 		pr_err("You probably need to specify IP address on "
1432 		       "multicast interface.\n");
1433 
1434 	IP_VS_DBG(7, "binding socket with (%s) %pI4\n",
1435 		  dev->name, &addr);
1436 
1437 	/* Now bind the socket with the address of multicast interface */
1438 	sin.sin_family	     = AF_INET;
1439 	sin.sin_addr.s_addr  = addr;
1440 	sin.sin_port         = 0;
1441 
1442 	return kernel_bind(sock, (struct sockaddr *)&sin, sizeof(sin));
1443 }
1444 
get_mcast_sockaddr(union ipvs_sockaddr * sa,int * salen,struct ipvs_sync_daemon_cfg * c,int id)1445 static void get_mcast_sockaddr(union ipvs_sockaddr *sa, int *salen,
1446 			       struct ipvs_sync_daemon_cfg *c, int id)
1447 {
1448 	if (AF_INET6 == c->mcast_af) {
1449 		sa->in6 = (struct sockaddr_in6) {
1450 			.sin6_family = AF_INET6,
1451 			.sin6_port = htons(c->mcast_port + id),
1452 		};
1453 		sa->in6.sin6_addr = c->mcast_group.in6;
1454 		*salen = sizeof(sa->in6);
1455 	} else {
1456 		sa->in = (struct sockaddr_in) {
1457 			.sin_family = AF_INET,
1458 			.sin_port = htons(c->mcast_port + id),
1459 		};
1460 		sa->in.sin_addr = c->mcast_group.in;
1461 		*salen = sizeof(sa->in);
1462 	}
1463 }
1464 
1465 /*
1466  *      Set up sending multicast socket over UDP
1467  */
make_send_sock(struct netns_ipvs * ipvs,int id,struct net_device * dev,struct socket ** sock_ret)1468 static int make_send_sock(struct netns_ipvs *ipvs, int id,
1469 			  struct net_device *dev, struct socket **sock_ret)
1470 {
1471 	/* multicast addr */
1472 	union ipvs_sockaddr mcast_addr;
1473 	struct socket *sock;
1474 	int result, salen;
1475 
1476 	/* First create a socket */
1477 	result = sock_create_kern(ipvs->net, ipvs->mcfg.mcast_af, SOCK_DGRAM,
1478 				  IPPROTO_UDP, &sock);
1479 	if (result < 0) {
1480 		pr_err("Error during creation of socket; terminating\n");
1481 		goto error;
1482 	}
1483 	*sock_ret = sock;
1484 	result = set_mcast_if(sock->sk, dev);
1485 	if (result < 0) {
1486 		pr_err("Error setting outbound mcast interface\n");
1487 		goto error;
1488 	}
1489 
1490 	set_mcast_loop(sock->sk, 0);
1491 	set_mcast_ttl(sock->sk, ipvs->mcfg.mcast_ttl);
1492 	/* Allow fragmentation if MTU changes */
1493 	set_mcast_pmtudisc(sock->sk, IP_PMTUDISC_DONT);
1494 	result = sysctl_sync_sock_size(ipvs);
1495 	if (result > 0)
1496 		set_sock_size(sock->sk, 1, result);
1497 
1498 	if (AF_INET == ipvs->mcfg.mcast_af)
1499 		result = bind_mcastif_addr(sock, dev);
1500 	else
1501 		result = 0;
1502 	if (result < 0) {
1503 		pr_err("Error binding address of the mcast interface\n");
1504 		goto error;
1505 	}
1506 
1507 	get_mcast_sockaddr(&mcast_addr, &salen, &ipvs->mcfg, id);
1508 	result = kernel_connect(sock, (struct sockaddr *)&mcast_addr,
1509 				salen, 0);
1510 	if (result < 0) {
1511 		pr_err("Error connecting to the multicast addr\n");
1512 		goto error;
1513 	}
1514 
1515 	return 0;
1516 
1517 error:
1518 	return result;
1519 }
1520 
1521 
1522 /*
1523  *      Set up receiving multicast socket over UDP
1524  */
make_receive_sock(struct netns_ipvs * ipvs,int id,struct net_device * dev,struct socket ** sock_ret)1525 static int make_receive_sock(struct netns_ipvs *ipvs, int id,
1526 			     struct net_device *dev, struct socket **sock_ret)
1527 {
1528 	/* multicast addr */
1529 	union ipvs_sockaddr mcast_addr;
1530 	struct socket *sock;
1531 	int result, salen;
1532 
1533 	/* First create a socket */
1534 	result = sock_create_kern(ipvs->net, ipvs->bcfg.mcast_af, SOCK_DGRAM,
1535 				  IPPROTO_UDP, &sock);
1536 	if (result < 0) {
1537 		pr_err("Error during creation of socket; terminating\n");
1538 		goto error;
1539 	}
1540 	*sock_ret = sock;
1541 	/* it is equivalent to the REUSEADDR option in user-space */
1542 	sock->sk->sk_reuse = SK_CAN_REUSE;
1543 	result = sysctl_sync_sock_size(ipvs);
1544 	if (result > 0)
1545 		set_sock_size(sock->sk, 0, result);
1546 
1547 	get_mcast_sockaddr(&mcast_addr, &salen, &ipvs->bcfg, id);
1548 	sock->sk->sk_bound_dev_if = dev->ifindex;
1549 	result = kernel_bind(sock, (struct sockaddr *)&mcast_addr, salen);
1550 	if (result < 0) {
1551 		pr_err("Error binding to the multicast addr\n");
1552 		goto error;
1553 	}
1554 
1555 	/* join the multicast group */
1556 #ifdef CONFIG_IP_VS_IPV6
1557 	if (ipvs->bcfg.mcast_af == AF_INET6)
1558 		result = join_mcast_group6(sock->sk, &mcast_addr.in6.sin6_addr,
1559 					   dev);
1560 	else
1561 #endif
1562 		result = join_mcast_group(sock->sk, &mcast_addr.in.sin_addr,
1563 					  dev);
1564 	if (result < 0) {
1565 		pr_err("Error joining to the multicast group\n");
1566 		goto error;
1567 	}
1568 
1569 	return 0;
1570 
1571 error:
1572 	return result;
1573 }
1574 
1575 
1576 static int
ip_vs_send_async(struct socket * sock,const char * buffer,const size_t length)1577 ip_vs_send_async(struct socket *sock, const char *buffer, const size_t length)
1578 {
1579 	struct msghdr	msg = {.msg_flags = MSG_DONTWAIT|MSG_NOSIGNAL};
1580 	struct kvec	iov;
1581 	int		len;
1582 
1583 	iov.iov_base     = (void *)buffer;
1584 	iov.iov_len      = length;
1585 
1586 	len = kernel_sendmsg(sock, &msg, &iov, 1, (size_t)(length));
1587 
1588 	return len;
1589 }
1590 
1591 static int
ip_vs_send_sync_msg(struct socket * sock,struct ip_vs_sync_mesg * msg)1592 ip_vs_send_sync_msg(struct socket *sock, struct ip_vs_sync_mesg *msg)
1593 {
1594 	int msize;
1595 	int ret;
1596 
1597 	msize = ntohs(msg->size);
1598 
1599 	ret = ip_vs_send_async(sock, (char *)msg, msize);
1600 	if (ret >= 0 || ret == -EAGAIN)
1601 		return ret;
1602 	pr_err("ip_vs_send_async error %d\n", ret);
1603 	return 0;
1604 }
1605 
1606 static int
ip_vs_receive(struct socket * sock,char * buffer,const size_t buflen)1607 ip_vs_receive(struct socket *sock, char *buffer, const size_t buflen)
1608 {
1609 	struct msghdr		msg = {NULL,};
1610 	struct kvec		iov = {buffer, buflen};
1611 	int			len;
1612 
1613 	/* Receive a packet */
1614 	iov_iter_kvec(&msg.msg_iter, ITER_DEST, &iov, 1, buflen);
1615 	len = sock_recvmsg(sock, &msg, MSG_DONTWAIT);
1616 	if (len < 0)
1617 		return len;
1618 
1619 	return len;
1620 }
1621 
1622 /* Wakeup the master thread for sending */
master_wakeup_work_handler(struct work_struct * work)1623 static void master_wakeup_work_handler(struct work_struct *work)
1624 {
1625 	struct ipvs_master_sync_state *ms =
1626 		container_of(work, struct ipvs_master_sync_state,
1627 			     master_wakeup_work.work);
1628 	struct netns_ipvs *ipvs = ms->ipvs;
1629 
1630 	spin_lock_bh(&ipvs->sync_lock);
1631 	if (ms->sync_queue_len &&
1632 	    ms->sync_queue_delay < IPVS_SYNC_WAKEUP_RATE) {
1633 		int id = (int)(ms - ipvs->ms);
1634 
1635 		ms->sync_queue_delay = IPVS_SYNC_WAKEUP_RATE;
1636 		wake_up_process(ipvs->master_tinfo[id].task);
1637 	}
1638 	spin_unlock_bh(&ipvs->sync_lock);
1639 }
1640 
1641 /* Get next buffer to send */
1642 static inline struct ip_vs_sync_buff *
next_sync_buff(struct netns_ipvs * ipvs,struct ipvs_master_sync_state * ms)1643 next_sync_buff(struct netns_ipvs *ipvs, struct ipvs_master_sync_state *ms)
1644 {
1645 	struct ip_vs_sync_buff *sb;
1646 
1647 	sb = sb_dequeue(ipvs, ms);
1648 	if (sb)
1649 		return sb;
1650 	/* Do not delay entries in buffer for more than 2 seconds */
1651 	return get_curr_sync_buff(ipvs, ms, IPVS_SYNC_FLUSH_TIME);
1652 }
1653 
sync_thread_master(void * data)1654 static int sync_thread_master(void *data)
1655 {
1656 	struct ip_vs_sync_thread_data *tinfo = data;
1657 	struct netns_ipvs *ipvs = tinfo->ipvs;
1658 	struct ipvs_master_sync_state *ms = &ipvs->ms[tinfo->id];
1659 	struct sock *sk = tinfo->sock->sk;
1660 	struct ip_vs_sync_buff *sb;
1661 
1662 	pr_info("sync thread started: state = MASTER, mcast_ifn = %s, "
1663 		"syncid = %d, id = %d\n",
1664 		ipvs->mcfg.mcast_ifn, ipvs->mcfg.syncid, tinfo->id);
1665 
1666 	for (;;) {
1667 		sb = next_sync_buff(ipvs, ms);
1668 		if (unlikely(kthread_should_stop()))
1669 			break;
1670 		if (!sb) {
1671 			schedule_timeout(IPVS_SYNC_CHECK_PERIOD);
1672 			continue;
1673 		}
1674 		while (ip_vs_send_sync_msg(tinfo->sock, sb->mesg) < 0) {
1675 			/* (Ab)use interruptible sleep to avoid increasing
1676 			 * the load avg.
1677 			 */
1678 			__wait_event_interruptible(*sk_sleep(sk),
1679 						   sock_writeable(sk) ||
1680 						   kthread_should_stop());
1681 			if (unlikely(kthread_should_stop()))
1682 				goto done;
1683 		}
1684 		ip_vs_sync_buff_release(sb);
1685 	}
1686 
1687 done:
1688 	__set_current_state(TASK_RUNNING);
1689 	if (sb)
1690 		ip_vs_sync_buff_release(sb);
1691 
1692 	/* clean up the sync_buff queue */
1693 	while ((sb = sb_dequeue(ipvs, ms)))
1694 		ip_vs_sync_buff_release(sb);
1695 	__set_current_state(TASK_RUNNING);
1696 
1697 	/* clean up the current sync_buff */
1698 	sb = get_curr_sync_buff(ipvs, ms, 0);
1699 	if (sb)
1700 		ip_vs_sync_buff_release(sb);
1701 
1702 	return 0;
1703 }
1704 
1705 
sync_thread_backup(void * data)1706 static int sync_thread_backup(void *data)
1707 {
1708 	struct ip_vs_sync_thread_data *tinfo = data;
1709 	struct netns_ipvs *ipvs = tinfo->ipvs;
1710 	struct sock *sk = tinfo->sock->sk;
1711 	struct udp_sock *up = udp_sk(sk);
1712 	int len;
1713 
1714 	pr_info("sync thread started: state = BACKUP, mcast_ifn = %s, "
1715 		"syncid = %d, id = %d\n",
1716 		ipvs->bcfg.mcast_ifn, ipvs->bcfg.syncid, tinfo->id);
1717 
1718 	while (!kthread_should_stop()) {
1719 		wait_event_interruptible(*sk_sleep(sk),
1720 					 !skb_queue_empty_lockless(&sk->sk_receive_queue) ||
1721 					 !skb_queue_empty_lockless(&up->reader_queue) ||
1722 					 kthread_should_stop());
1723 
1724 		/* do we have data now? */
1725 		while (!skb_queue_empty_lockless(&sk->sk_receive_queue) ||
1726 		       !skb_queue_empty_lockless(&up->reader_queue)) {
1727 			len = ip_vs_receive(tinfo->sock, tinfo->buf,
1728 					ipvs->bcfg.sync_maxlen);
1729 			if (len <= 0) {
1730 				if (len != -EAGAIN)
1731 					pr_err("receiving message error\n");
1732 				break;
1733 			}
1734 
1735 			ip_vs_process_message(ipvs, tinfo->buf, len);
1736 		}
1737 	}
1738 
1739 	return 0;
1740 }
1741 
1742 
start_sync_thread(struct netns_ipvs * ipvs,struct ipvs_sync_daemon_cfg * c,int state)1743 int start_sync_thread(struct netns_ipvs *ipvs, struct ipvs_sync_daemon_cfg *c,
1744 		      int state)
1745 {
1746 	struct ip_vs_sync_thread_data *ti = NULL, *tinfo;
1747 	struct task_struct *task;
1748 	struct net_device *dev;
1749 	char *name;
1750 	int (*threadfn)(void *data);
1751 	int id = 0, count, hlen;
1752 	int result = -ENOMEM;
1753 	u16 mtu, min_mtu;
1754 
1755 	IP_VS_DBG(7, "%s(): pid %d\n", __func__, task_pid_nr(current));
1756 	IP_VS_DBG(7, "Each ip_vs_sync_conn entry needs %zd bytes\n",
1757 		  sizeof(struct ip_vs_sync_conn_v0));
1758 
1759 	/* increase the module use count */
1760 	if (!ip_vs_use_count_inc())
1761 		return -ENOPROTOOPT;
1762 
1763 	/* Do not hold one mutex and then to block on another */
1764 	for (;;) {
1765 		rtnl_lock();
1766 		if (mutex_trylock(&ipvs->sync_mutex))
1767 			break;
1768 		rtnl_unlock();
1769 		mutex_lock(&ipvs->sync_mutex);
1770 		if (rtnl_trylock())
1771 			break;
1772 		mutex_unlock(&ipvs->sync_mutex);
1773 	}
1774 
1775 	if (!ipvs->sync_state) {
1776 		count = clamp(sysctl_sync_ports(ipvs), 1, IPVS_SYNC_PORTS_MAX);
1777 		ipvs->threads_mask = count - 1;
1778 	} else
1779 		count = ipvs->threads_mask + 1;
1780 
1781 	if (c->mcast_af == AF_UNSPEC) {
1782 		c->mcast_af = AF_INET;
1783 		c->mcast_group.ip = cpu_to_be32(IP_VS_SYNC_GROUP);
1784 	}
1785 	if (!c->mcast_port)
1786 		c->mcast_port = IP_VS_SYNC_PORT;
1787 	if (!c->mcast_ttl)
1788 		c->mcast_ttl = 1;
1789 
1790 	dev = __dev_get_by_name(ipvs->net, c->mcast_ifn);
1791 	if (!dev) {
1792 		pr_err("Unknown mcast interface: %s\n", c->mcast_ifn);
1793 		result = -ENODEV;
1794 		goto out_early;
1795 	}
1796 	hlen = (AF_INET6 == c->mcast_af) ?
1797 	       sizeof(struct ipv6hdr) + sizeof(struct udphdr) :
1798 	       sizeof(struct iphdr) + sizeof(struct udphdr);
1799 	mtu = (state == IP_VS_STATE_BACKUP) ?
1800 		  clamp(dev->mtu, 1500U, 65535U) : 1500U;
1801 	min_mtu = (state == IP_VS_STATE_BACKUP) ? 1024 : 1;
1802 
1803 	if (c->sync_maxlen)
1804 		c->sync_maxlen = clamp_t(unsigned int,
1805 					 c->sync_maxlen, min_mtu,
1806 					 65535 - hlen);
1807 	else
1808 		c->sync_maxlen = mtu - hlen;
1809 
1810 	if (state == IP_VS_STATE_MASTER) {
1811 		result = -EEXIST;
1812 		if (ipvs->ms)
1813 			goto out_early;
1814 
1815 		ipvs->mcfg = *c;
1816 		name = "ipvs-m:%d:%d";
1817 		threadfn = sync_thread_master;
1818 	} else if (state == IP_VS_STATE_BACKUP) {
1819 		result = -EEXIST;
1820 		if (ipvs->backup_tinfo)
1821 			goto out_early;
1822 
1823 		ipvs->bcfg = *c;
1824 		name = "ipvs-b:%d:%d";
1825 		threadfn = sync_thread_backup;
1826 	} else {
1827 		result = -EINVAL;
1828 		goto out_early;
1829 	}
1830 
1831 	if (state == IP_VS_STATE_MASTER) {
1832 		struct ipvs_master_sync_state *ms;
1833 
1834 		result = -ENOMEM;
1835 		ipvs->ms = kcalloc(count, sizeof(ipvs->ms[0]), GFP_KERNEL);
1836 		if (!ipvs->ms)
1837 			goto out;
1838 		ms = ipvs->ms;
1839 		for (id = 0; id < count; id++, ms++) {
1840 			INIT_LIST_HEAD(&ms->sync_queue);
1841 			ms->sync_queue_len = 0;
1842 			ms->sync_queue_delay = 0;
1843 			INIT_DELAYED_WORK(&ms->master_wakeup_work,
1844 					  master_wakeup_work_handler);
1845 			ms->ipvs = ipvs;
1846 		}
1847 	}
1848 	result = -ENOMEM;
1849 	ti = kcalloc(count, sizeof(struct ip_vs_sync_thread_data),
1850 		     GFP_KERNEL);
1851 	if (!ti)
1852 		goto out;
1853 
1854 	for (id = 0; id < count; id++) {
1855 		tinfo = &ti[id];
1856 		tinfo->ipvs = ipvs;
1857 		if (state == IP_VS_STATE_BACKUP) {
1858 			result = -ENOMEM;
1859 			tinfo->buf = kmalloc(ipvs->bcfg.sync_maxlen,
1860 					     GFP_KERNEL);
1861 			if (!tinfo->buf)
1862 				goto out;
1863 		}
1864 		tinfo->id = id;
1865 		if (state == IP_VS_STATE_MASTER)
1866 			result = make_send_sock(ipvs, id, dev, &tinfo->sock);
1867 		else
1868 			result = make_receive_sock(ipvs, id, dev, &tinfo->sock);
1869 		if (result < 0)
1870 			goto out;
1871 
1872 		task = kthread_run(threadfn, tinfo, name, ipvs->gen, id);
1873 		if (IS_ERR(task)) {
1874 			result = PTR_ERR(task);
1875 			goto out;
1876 		}
1877 		tinfo->task = task;
1878 	}
1879 
1880 	/* mark as active */
1881 
1882 	if (state == IP_VS_STATE_MASTER)
1883 		ipvs->master_tinfo = ti;
1884 	else
1885 		ipvs->backup_tinfo = ti;
1886 	spin_lock_bh(&ipvs->sync_buff_lock);
1887 	ipvs->sync_state |= state;
1888 	spin_unlock_bh(&ipvs->sync_buff_lock);
1889 
1890 	mutex_unlock(&ipvs->sync_mutex);
1891 	rtnl_unlock();
1892 
1893 	return 0;
1894 
1895 out:
1896 	/* We do not need RTNL lock anymore, release it here so that
1897 	 * sock_release below can use rtnl_lock to leave the mcast group.
1898 	 */
1899 	rtnl_unlock();
1900 	id = min(id, count - 1);
1901 	if (ti) {
1902 		for (tinfo = ti + id; tinfo >= ti; tinfo--) {
1903 			if (tinfo->task)
1904 				kthread_stop(tinfo->task);
1905 		}
1906 	}
1907 	if (!(ipvs->sync_state & IP_VS_STATE_MASTER)) {
1908 		kfree(ipvs->ms);
1909 		ipvs->ms = NULL;
1910 	}
1911 	mutex_unlock(&ipvs->sync_mutex);
1912 
1913 	/* No more mutexes, release socks */
1914 	if (ti) {
1915 		for (tinfo = ti + id; tinfo >= ti; tinfo--) {
1916 			if (tinfo->sock)
1917 				sock_release(tinfo->sock);
1918 			kfree(tinfo->buf);
1919 		}
1920 		kfree(ti);
1921 	}
1922 
1923 	/* decrease the module use count */
1924 	ip_vs_use_count_dec();
1925 	return result;
1926 
1927 out_early:
1928 	mutex_unlock(&ipvs->sync_mutex);
1929 	rtnl_unlock();
1930 
1931 	/* decrease the module use count */
1932 	ip_vs_use_count_dec();
1933 	return result;
1934 }
1935 
1936 
stop_sync_thread(struct netns_ipvs * ipvs,int state)1937 int stop_sync_thread(struct netns_ipvs *ipvs, int state)
1938 {
1939 	struct ip_vs_sync_thread_data *ti, *tinfo;
1940 	int id;
1941 	int retc = -EINVAL;
1942 
1943 	IP_VS_DBG(7, "%s(): pid %d\n", __func__, task_pid_nr(current));
1944 
1945 	mutex_lock(&ipvs->sync_mutex);
1946 	if (state == IP_VS_STATE_MASTER) {
1947 		retc = -ESRCH;
1948 		if (!ipvs->ms)
1949 			goto err;
1950 		ti = ipvs->master_tinfo;
1951 
1952 		/*
1953 		 * The lock synchronizes with sb_queue_tail(), so that we don't
1954 		 * add sync buffers to the queue, when we are already in
1955 		 * progress of stopping the master sync daemon.
1956 		 */
1957 
1958 		spin_lock_bh(&ipvs->sync_buff_lock);
1959 		spin_lock(&ipvs->sync_lock);
1960 		ipvs->sync_state &= ~IP_VS_STATE_MASTER;
1961 		spin_unlock(&ipvs->sync_lock);
1962 		spin_unlock_bh(&ipvs->sync_buff_lock);
1963 
1964 		retc = 0;
1965 		for (id = ipvs->threads_mask; id >= 0; id--) {
1966 			struct ipvs_master_sync_state *ms = &ipvs->ms[id];
1967 			int ret;
1968 
1969 			tinfo = &ti[id];
1970 			pr_info("stopping master sync thread %d ...\n",
1971 				task_pid_nr(tinfo->task));
1972 			cancel_delayed_work_sync(&ms->master_wakeup_work);
1973 			ret = kthread_stop(tinfo->task);
1974 			if (retc >= 0)
1975 				retc = ret;
1976 		}
1977 		kfree(ipvs->ms);
1978 		ipvs->ms = NULL;
1979 		ipvs->master_tinfo = NULL;
1980 	} else if (state == IP_VS_STATE_BACKUP) {
1981 		retc = -ESRCH;
1982 		if (!ipvs->backup_tinfo)
1983 			goto err;
1984 		ti = ipvs->backup_tinfo;
1985 
1986 		ipvs->sync_state &= ~IP_VS_STATE_BACKUP;
1987 		retc = 0;
1988 		for (id = ipvs->threads_mask; id >= 0; id--) {
1989 			int ret;
1990 
1991 			tinfo = &ti[id];
1992 			pr_info("stopping backup sync thread %d ...\n",
1993 				task_pid_nr(tinfo->task));
1994 			ret = kthread_stop(tinfo->task);
1995 			if (retc >= 0)
1996 				retc = ret;
1997 		}
1998 		ipvs->backup_tinfo = NULL;
1999 	} else {
2000 		goto err;
2001 	}
2002 	id = ipvs->threads_mask;
2003 	mutex_unlock(&ipvs->sync_mutex);
2004 
2005 	/* No more mutexes, release socks */
2006 	for (tinfo = ti + id; tinfo >= ti; tinfo--) {
2007 		if (tinfo->sock)
2008 			sock_release(tinfo->sock);
2009 		kfree(tinfo->buf);
2010 	}
2011 	kfree(ti);
2012 
2013 	/* decrease the module use count */
2014 	ip_vs_use_count_dec();
2015 	return retc;
2016 
2017 err:
2018 	mutex_unlock(&ipvs->sync_mutex);
2019 	return retc;
2020 }
2021 
2022 /*
2023  * Initialize data struct for each netns
2024  */
ip_vs_sync_net_init(struct netns_ipvs * ipvs)2025 int __net_init ip_vs_sync_net_init(struct netns_ipvs *ipvs)
2026 {
2027 	__mutex_init(&ipvs->sync_mutex, "ipvs->sync_mutex", &__ipvs_sync_key);
2028 	spin_lock_init(&ipvs->sync_lock);
2029 	spin_lock_init(&ipvs->sync_buff_lock);
2030 	return 0;
2031 }
2032 
ip_vs_sync_net_cleanup(struct netns_ipvs * ipvs)2033 void ip_vs_sync_net_cleanup(struct netns_ipvs *ipvs)
2034 {
2035 	int retc;
2036 
2037 	retc = stop_sync_thread(ipvs, IP_VS_STATE_MASTER);
2038 	if (retc && retc != -ESRCH)
2039 		pr_err("Failed to stop Master Daemon\n");
2040 
2041 	retc = stop_sync_thread(ipvs, IP_VS_STATE_BACKUP);
2042 	if (retc && retc != -ESRCH)
2043 		pr_err("Failed to stop Backup Daemon\n");
2044 }
2045