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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 #define SYNC_MESG_HEADER_LEN	4
246 #define MAX_CONNS_PER_SYNCBUFF	255 /* nr_conns in ip_vs_sync_mesg is 8 bit */
247 
248 /* Version 0 header */
249 struct ip_vs_sync_mesg_v0 {
250 	__u8                    nr_conns;
251 	__u8                    syncid;
252 	__be16                  size;
253 
254 	/* ip_vs_sync_conn entries start here */
255 };
256 
257 /* Version 1 header */
258 struct ip_vs_sync_mesg {
259 	__u8			reserved;	/* must be zero */
260 	__u8			syncid;
261 	__be16			size;
262 	__u8			nr_conns;
263 	__s8			version;	/* SYNC_PROTO_VER  */
264 	__u16			spare;
265 	/* ip_vs_sync_conn entries start here */
266 };
267 
268 union ipvs_sockaddr {
269 	struct sockaddr_in	in;
270 	struct sockaddr_in6	in6;
271 };
272 
273 struct ip_vs_sync_buff {
274 	struct list_head        list;
275 	unsigned long           firstuse;
276 
277 	/* pointers for the message data */
278 	struct ip_vs_sync_mesg  *mesg;
279 	unsigned char           *head;
280 	unsigned char           *end;
281 };
282 
283 /*
284  * Copy of struct ip_vs_seq
285  * From unaligned network order to aligned host order
286  */
ntoh_seq(struct ip_vs_seq * no,struct ip_vs_seq * ho)287 static void ntoh_seq(struct ip_vs_seq *no, struct ip_vs_seq *ho)
288 {
289 	memset(ho, 0, sizeof(*ho));
290 	ho->init_seq       = get_unaligned_be32(&no->init_seq);
291 	ho->delta          = get_unaligned_be32(&no->delta);
292 	ho->previous_delta = get_unaligned_be32(&no->previous_delta);
293 }
294 
295 /*
296  * Copy of struct ip_vs_seq
297  * From Aligned host order to unaligned network order
298  */
hton_seq(struct ip_vs_seq * ho,struct ip_vs_seq * no)299 static void hton_seq(struct ip_vs_seq *ho, struct ip_vs_seq *no)
300 {
301 	put_unaligned_be32(ho->init_seq, &no->init_seq);
302 	put_unaligned_be32(ho->delta, &no->delta);
303 	put_unaligned_be32(ho->previous_delta, &no->previous_delta);
304 }
305 
306 static inline struct ip_vs_sync_buff *
sb_dequeue(struct netns_ipvs * ipvs,struct ipvs_master_sync_state * ms)307 sb_dequeue(struct netns_ipvs *ipvs, struct ipvs_master_sync_state *ms)
308 {
309 	struct ip_vs_sync_buff *sb;
310 
311 	spin_lock_bh(&ipvs->sync_lock);
312 	if (list_empty(&ms->sync_queue)) {
313 		sb = NULL;
314 		__set_current_state(TASK_INTERRUPTIBLE);
315 	} else {
316 		sb = list_entry(ms->sync_queue.next, struct ip_vs_sync_buff,
317 				list);
318 		list_del(&sb->list);
319 		ms->sync_queue_len--;
320 		if (!ms->sync_queue_len)
321 			ms->sync_queue_delay = 0;
322 	}
323 	spin_unlock_bh(&ipvs->sync_lock);
324 
325 	return sb;
326 }
327 
328 /*
329  * Create a new sync buffer for Version 1 proto.
330  */
331 static inline struct ip_vs_sync_buff *
ip_vs_sync_buff_create(struct netns_ipvs * ipvs,unsigned int len)332 ip_vs_sync_buff_create(struct netns_ipvs *ipvs, unsigned int len)
333 {
334 	struct ip_vs_sync_buff *sb;
335 
336 	if (!(sb=kmalloc(sizeof(struct ip_vs_sync_buff), GFP_ATOMIC)))
337 		return NULL;
338 
339 	len = max_t(unsigned int, len + sizeof(struct ip_vs_sync_mesg),
340 		    ipvs->mcfg.sync_maxlen);
341 	sb->mesg = kmalloc(len, GFP_ATOMIC);
342 	if (!sb->mesg) {
343 		kfree(sb);
344 		return NULL;
345 	}
346 	sb->mesg->reserved = 0;  /* old nr_conns i.e. must be zero now */
347 	sb->mesg->version = SYNC_PROTO_VER;
348 	sb->mesg->syncid = ipvs->mcfg.syncid;
349 	sb->mesg->size = htons(sizeof(struct ip_vs_sync_mesg));
350 	sb->mesg->nr_conns = 0;
351 	sb->mesg->spare = 0;
352 	sb->head = (unsigned char *)sb->mesg + sizeof(struct ip_vs_sync_mesg);
353 	sb->end = (unsigned char *)sb->mesg + len;
354 
355 	sb->firstuse = jiffies;
356 	return sb;
357 }
358 
ip_vs_sync_buff_release(struct ip_vs_sync_buff * sb)359 static inline void ip_vs_sync_buff_release(struct ip_vs_sync_buff *sb)
360 {
361 	kfree(sb->mesg);
362 	kfree(sb);
363 }
364 
sb_queue_tail(struct netns_ipvs * ipvs,struct ipvs_master_sync_state * ms)365 static inline void sb_queue_tail(struct netns_ipvs *ipvs,
366 				 struct ipvs_master_sync_state *ms)
367 {
368 	struct ip_vs_sync_buff *sb = ms->sync_buff;
369 
370 	spin_lock(&ipvs->sync_lock);
371 	if (ipvs->sync_state & IP_VS_STATE_MASTER &&
372 	    ms->sync_queue_len < sysctl_sync_qlen_max(ipvs)) {
373 		if (!ms->sync_queue_len)
374 			schedule_delayed_work(&ms->master_wakeup_work,
375 					      max(IPVS_SYNC_SEND_DELAY, 1));
376 		ms->sync_queue_len++;
377 		list_add_tail(&sb->list, &ms->sync_queue);
378 		if ((++ms->sync_queue_delay) == IPVS_SYNC_WAKEUP_RATE) {
379 			int id = (int)(ms - ipvs->ms);
380 
381 			wake_up_process(ipvs->master_tinfo[id].task);
382 		}
383 	} else
384 		ip_vs_sync_buff_release(sb);
385 	spin_unlock(&ipvs->sync_lock);
386 }
387 
388 /*
389  *	Get the current sync buffer if it has been created for more
390  *	than the specified time or the specified time is zero.
391  */
392 static inline struct ip_vs_sync_buff *
get_curr_sync_buff(struct netns_ipvs * ipvs,struct ipvs_master_sync_state * ms,unsigned long time)393 get_curr_sync_buff(struct netns_ipvs *ipvs, struct ipvs_master_sync_state *ms,
394 		   unsigned long time)
395 {
396 	struct ip_vs_sync_buff *sb;
397 
398 	spin_lock_bh(&ipvs->sync_buff_lock);
399 	sb = ms->sync_buff;
400 	if (sb && time_after_eq(jiffies - sb->firstuse, time)) {
401 		ms->sync_buff = NULL;
402 		__set_current_state(TASK_RUNNING);
403 	} else
404 		sb = NULL;
405 	spin_unlock_bh(&ipvs->sync_buff_lock);
406 	return sb;
407 }
408 
409 static inline int
select_master_thread_id(struct netns_ipvs * ipvs,struct ip_vs_conn * cp)410 select_master_thread_id(struct netns_ipvs *ipvs, struct ip_vs_conn *cp)
411 {
412 	return ((long) cp >> (1 + ilog2(sizeof(*cp)))) & ipvs->threads_mask;
413 }
414 
415 /*
416  * Create a new sync buffer for Version 0 proto.
417  */
418 static inline struct ip_vs_sync_buff *
ip_vs_sync_buff_create_v0(struct netns_ipvs * ipvs,unsigned int len)419 ip_vs_sync_buff_create_v0(struct netns_ipvs *ipvs, unsigned int len)
420 {
421 	struct ip_vs_sync_buff *sb;
422 	struct ip_vs_sync_mesg_v0 *mesg;
423 
424 	if (!(sb=kmalloc(sizeof(struct ip_vs_sync_buff), GFP_ATOMIC)))
425 		return NULL;
426 
427 	len = max_t(unsigned int, len + sizeof(struct ip_vs_sync_mesg_v0),
428 		    ipvs->mcfg.sync_maxlen);
429 	sb->mesg = kmalloc(len, GFP_ATOMIC);
430 	if (!sb->mesg) {
431 		kfree(sb);
432 		return NULL;
433 	}
434 	mesg = (struct ip_vs_sync_mesg_v0 *)sb->mesg;
435 	mesg->nr_conns = 0;
436 	mesg->syncid = ipvs->mcfg.syncid;
437 	mesg->size = htons(sizeof(struct ip_vs_sync_mesg_v0));
438 	sb->head = (unsigned char *)mesg + sizeof(struct ip_vs_sync_mesg_v0);
439 	sb->end = (unsigned char *)mesg + len;
440 	sb->firstuse = jiffies;
441 	return sb;
442 }
443 
444 /* Check if connection is controlled by persistence */
in_persistence(struct ip_vs_conn * cp)445 static inline bool in_persistence(struct ip_vs_conn *cp)
446 {
447 	for (cp = cp->control; cp; cp = cp->control) {
448 		if (cp->flags & IP_VS_CONN_F_TEMPLATE)
449 			return true;
450 	}
451 	return false;
452 }
453 
454 /* Check if conn should be synced.
455  * pkts: conn packets, use sysctl_sync_threshold to avoid packet check
456  * - (1) sync_refresh_period: reduce sync rate. Additionally, retry
457  *	sync_retries times with period of sync_refresh_period/8
458  * - (2) if both sync_refresh_period and sync_period are 0 send sync only
459  *	for state changes or only once when pkts matches sync_threshold
460  * - (3) templates: rate can be reduced only with sync_refresh_period or
461  *	with (2)
462  */
ip_vs_sync_conn_needed(struct netns_ipvs * ipvs,struct ip_vs_conn * cp,int pkts)463 static int ip_vs_sync_conn_needed(struct netns_ipvs *ipvs,
464 				  struct ip_vs_conn *cp, int pkts)
465 {
466 	unsigned long orig = READ_ONCE(cp->sync_endtime);
467 	unsigned long now = jiffies;
468 	unsigned long n = (now + cp->timeout) & ~3UL;
469 	unsigned int sync_refresh_period;
470 	int sync_period;
471 	int force;
472 
473 	/* Check if we sync in current state */
474 	if (unlikely(cp->flags & IP_VS_CONN_F_TEMPLATE))
475 		force = 0;
476 	else if (unlikely(sysctl_sync_persist_mode(ipvs) && in_persistence(cp)))
477 		return 0;
478 	else if (likely(cp->protocol == IPPROTO_TCP)) {
479 		if (!((1 << cp->state) &
480 		      ((1 << IP_VS_TCP_S_ESTABLISHED) |
481 		       (1 << IP_VS_TCP_S_FIN_WAIT) |
482 		       (1 << IP_VS_TCP_S_CLOSE) |
483 		       (1 << IP_VS_TCP_S_CLOSE_WAIT) |
484 		       (1 << IP_VS_TCP_S_TIME_WAIT))))
485 			return 0;
486 		force = cp->state != cp->old_state;
487 		if (force && cp->state != IP_VS_TCP_S_ESTABLISHED)
488 			goto set;
489 	} else if (unlikely(cp->protocol == IPPROTO_SCTP)) {
490 		if (!((1 << cp->state) &
491 		      ((1 << IP_VS_SCTP_S_ESTABLISHED) |
492 		       (1 << IP_VS_SCTP_S_SHUTDOWN_SENT) |
493 		       (1 << IP_VS_SCTP_S_SHUTDOWN_RECEIVED) |
494 		       (1 << IP_VS_SCTP_S_SHUTDOWN_ACK_SENT) |
495 		       (1 << IP_VS_SCTP_S_CLOSED))))
496 			return 0;
497 		force = cp->state != cp->old_state;
498 		if (force && cp->state != IP_VS_SCTP_S_ESTABLISHED)
499 			goto set;
500 	} else {
501 		/* UDP or another protocol with single state */
502 		force = 0;
503 	}
504 
505 	sync_refresh_period = sysctl_sync_refresh_period(ipvs);
506 	if (sync_refresh_period > 0) {
507 		long diff = n - orig;
508 		long min_diff = max(cp->timeout >> 1, 10UL * HZ);
509 
510 		/* Avoid sync if difference is below sync_refresh_period
511 		 * and below the half timeout.
512 		 */
513 		if (abs(diff) < min_t(long, sync_refresh_period, min_diff)) {
514 			int retries = orig & 3;
515 
516 			if (retries >= sysctl_sync_retries(ipvs))
517 				return 0;
518 			if (time_before(now, orig - cp->timeout +
519 					(sync_refresh_period >> 3)))
520 				return 0;
521 			n |= retries + 1;
522 		}
523 	}
524 	sync_period = sysctl_sync_period(ipvs);
525 	if (sync_period > 0) {
526 		if (!(cp->flags & IP_VS_CONN_F_TEMPLATE) &&
527 		    pkts % sync_period != sysctl_sync_threshold(ipvs))
528 			return 0;
529 	} else if (!sync_refresh_period &&
530 		   pkts != sysctl_sync_threshold(ipvs))
531 		return 0;
532 
533 set:
534 	cp->old_state = cp->state;
535 	n = cmpxchg(&cp->sync_endtime, orig, n);
536 	return n == orig || force;
537 }
538 
539 /*
540  *      Version 0 , could be switched in by sys_ctl.
541  *      Add an ip_vs_conn information into the current sync_buff.
542  */
ip_vs_sync_conn_v0(struct netns_ipvs * ipvs,struct ip_vs_conn * cp,int pkts)543 static void ip_vs_sync_conn_v0(struct netns_ipvs *ipvs, struct ip_vs_conn *cp,
544 			       int pkts)
545 {
546 	struct ip_vs_sync_mesg_v0 *m;
547 	struct ip_vs_sync_conn_v0 *s;
548 	struct ip_vs_sync_buff *buff;
549 	struct ipvs_master_sync_state *ms;
550 	int id;
551 	unsigned int len;
552 
553 	if (unlikely(cp->af != AF_INET))
554 		return;
555 	/* Do not sync ONE PACKET */
556 	if (cp->flags & IP_VS_CONN_F_ONE_PACKET)
557 		return;
558 
559 	if (!ip_vs_sync_conn_needed(ipvs, cp, pkts))
560 		return;
561 
562 	spin_lock_bh(&ipvs->sync_buff_lock);
563 	if (!(ipvs->sync_state & IP_VS_STATE_MASTER)) {
564 		spin_unlock_bh(&ipvs->sync_buff_lock);
565 		return;
566 	}
567 
568 	id = select_master_thread_id(ipvs, cp);
569 	ms = &ipvs->ms[id];
570 	buff = ms->sync_buff;
571 	len = (cp->flags & IP_VS_CONN_F_SEQ_MASK) ? FULL_CONN_SIZE :
572 		SIMPLE_CONN_SIZE;
573 	if (buff) {
574 		m = (struct ip_vs_sync_mesg_v0 *) buff->mesg;
575 		/* Send buffer if it is for v1 */
576 		if (buff->head + len > buff->end || !m->nr_conns) {
577 			sb_queue_tail(ipvs, ms);
578 			ms->sync_buff = NULL;
579 			buff = NULL;
580 		}
581 	}
582 	if (!buff) {
583 		buff = ip_vs_sync_buff_create_v0(ipvs, len);
584 		if (!buff) {
585 			spin_unlock_bh(&ipvs->sync_buff_lock);
586 			pr_err("ip_vs_sync_buff_create failed.\n");
587 			return;
588 		}
589 		ms->sync_buff = buff;
590 	}
591 
592 	m = (struct ip_vs_sync_mesg_v0 *) buff->mesg;
593 	s = (struct ip_vs_sync_conn_v0 *) buff->head;
594 
595 	/* copy members */
596 	s->reserved = 0;
597 	s->protocol = cp->protocol;
598 	s->cport = cp->cport;
599 	s->vport = cp->vport;
600 	s->dport = cp->dport;
601 	s->caddr = cp->caddr.ip;
602 	s->vaddr = cp->vaddr.ip;
603 	s->daddr = cp->daddr.ip;
604 	s->flags = htons(cp->flags & ~IP_VS_CONN_F_HASHED);
605 	s->state = htons(cp->state);
606 	if (cp->flags & IP_VS_CONN_F_SEQ_MASK) {
607 		struct ip_vs_sync_conn_options *opt =
608 			(struct ip_vs_sync_conn_options *)&s[1];
609 		memcpy(opt, &cp->in_seq, sizeof(*opt));
610 	}
611 
612 	m->nr_conns++;
613 	m->size = htons(ntohs(m->size) + len);
614 	buff->head += len;
615 	spin_unlock_bh(&ipvs->sync_buff_lock);
616 
617 	/* synchronize its controller if it has */
618 	cp = cp->control;
619 	if (cp) {
620 		if (cp->flags & IP_VS_CONN_F_TEMPLATE)
621 			pkts = atomic_add_return(1, &cp->in_pkts);
622 		else
623 			pkts = sysctl_sync_threshold(ipvs);
624 		ip_vs_sync_conn(ipvs, cp, pkts);
625 	}
626 }
627 
628 /*
629  *      Add an ip_vs_conn information into the current sync_buff.
630  *      Called by ip_vs_in.
631  *      Sending Version 1 messages
632  */
ip_vs_sync_conn(struct netns_ipvs * ipvs,struct ip_vs_conn * cp,int pkts)633 void ip_vs_sync_conn(struct netns_ipvs *ipvs, struct ip_vs_conn *cp, int pkts)
634 {
635 	struct ip_vs_sync_mesg *m;
636 	union ip_vs_sync_conn *s;
637 	struct ip_vs_sync_buff *buff;
638 	struct ipvs_master_sync_state *ms;
639 	int id;
640 	__u8 *p;
641 	unsigned int len, pe_name_len, pad;
642 
643 	/* Handle old version of the protocol */
644 	if (sysctl_sync_ver(ipvs) == 0) {
645 		ip_vs_sync_conn_v0(ipvs, cp, pkts);
646 		return;
647 	}
648 	/* Do not sync ONE PACKET */
649 	if (cp->flags & IP_VS_CONN_F_ONE_PACKET)
650 		goto control;
651 sloop:
652 	if (!ip_vs_sync_conn_needed(ipvs, cp, pkts))
653 		goto control;
654 
655 	/* Sanity checks */
656 	pe_name_len = 0;
657 	if (cp->pe_data_len) {
658 		if (!cp->pe_data || !cp->dest) {
659 			IP_VS_ERR_RL("SYNC, connection pe_data invalid\n");
660 			return;
661 		}
662 		pe_name_len = strnlen(cp->pe->name, IP_VS_PENAME_MAXLEN);
663 	}
664 
665 	spin_lock_bh(&ipvs->sync_buff_lock);
666 	if (!(ipvs->sync_state & IP_VS_STATE_MASTER)) {
667 		spin_unlock_bh(&ipvs->sync_buff_lock);
668 		return;
669 	}
670 
671 	id = select_master_thread_id(ipvs, cp);
672 	ms = &ipvs->ms[id];
673 
674 #ifdef CONFIG_IP_VS_IPV6
675 	if (cp->af == AF_INET6)
676 		len = sizeof(struct ip_vs_sync_v6);
677 	else
678 #endif
679 		len = sizeof(struct ip_vs_sync_v4);
680 
681 	if (cp->flags & IP_VS_CONN_F_SEQ_MASK)
682 		len += sizeof(struct ip_vs_sync_conn_options) + 2;
683 
684 	if (cp->pe_data_len)
685 		len += cp->pe_data_len + 2;	/* + Param hdr field */
686 	if (pe_name_len)
687 		len += pe_name_len + 2;
688 
689 	/* check if there is a space for this one  */
690 	pad = 0;
691 	buff = ms->sync_buff;
692 	if (buff) {
693 		m = buff->mesg;
694 		pad = (4 - (size_t) buff->head) & 3;
695 		/* Send buffer if it is for v0 */
696 		if (buff->head + len + pad > buff->end || m->reserved) {
697 			sb_queue_tail(ipvs, ms);
698 			ms->sync_buff = NULL;
699 			buff = NULL;
700 			pad = 0;
701 		}
702 	}
703 
704 	if (!buff) {
705 		buff = ip_vs_sync_buff_create(ipvs, len);
706 		if (!buff) {
707 			spin_unlock_bh(&ipvs->sync_buff_lock);
708 			pr_err("ip_vs_sync_buff_create failed.\n");
709 			return;
710 		}
711 		ms->sync_buff = buff;
712 		m = buff->mesg;
713 	}
714 
715 	p = buff->head;
716 	buff->head += pad + len;
717 	m->size = htons(ntohs(m->size) + pad + len);
718 	/* Add ev. padding from prev. sync_conn */
719 	while (pad--)
720 		*(p++) = 0;
721 
722 	s = (union ip_vs_sync_conn *)p;
723 
724 	/* Set message type  & copy members */
725 	s->v4.type = (cp->af == AF_INET6 ? STYPE_F_INET6 : 0);
726 	s->v4.ver_size = htons(len & SVER_MASK);	/* Version 0 */
727 	s->v4.flags = htonl(cp->flags & ~IP_VS_CONN_F_HASHED);
728 	s->v4.state = htons(cp->state);
729 	s->v4.protocol = cp->protocol;
730 	s->v4.cport = cp->cport;
731 	s->v4.vport = cp->vport;
732 	s->v4.dport = cp->dport;
733 	s->v4.fwmark = htonl(cp->fwmark);
734 	s->v4.timeout = htonl(cp->timeout / HZ);
735 	m->nr_conns++;
736 
737 #ifdef CONFIG_IP_VS_IPV6
738 	if (cp->af == AF_INET6) {
739 		p += sizeof(struct ip_vs_sync_v6);
740 		s->v6.caddr = cp->caddr.in6;
741 		s->v6.vaddr = cp->vaddr.in6;
742 		s->v6.daddr = cp->daddr.in6;
743 	} else
744 #endif
745 	{
746 		p += sizeof(struct ip_vs_sync_v4);	/* options ptr */
747 		s->v4.caddr = cp->caddr.ip;
748 		s->v4.vaddr = cp->vaddr.ip;
749 		s->v4.daddr = cp->daddr.ip;
750 	}
751 	if (cp->flags & IP_VS_CONN_F_SEQ_MASK) {
752 		*(p++) = IPVS_OPT_SEQ_DATA;
753 		*(p++) = sizeof(struct ip_vs_sync_conn_options);
754 		hton_seq((struct ip_vs_seq *)p, &cp->in_seq);
755 		p += sizeof(struct ip_vs_seq);
756 		hton_seq((struct ip_vs_seq *)p, &cp->out_seq);
757 		p += sizeof(struct ip_vs_seq);
758 	}
759 	/* Handle pe data */
760 	if (cp->pe_data_len && cp->pe_data) {
761 		*(p++) = IPVS_OPT_PE_DATA;
762 		*(p++) = cp->pe_data_len;
763 		memcpy(p, cp->pe_data, cp->pe_data_len);
764 		p += cp->pe_data_len;
765 		if (pe_name_len) {
766 			/* Add PE_NAME */
767 			*(p++) = IPVS_OPT_PE_NAME;
768 			*(p++) = pe_name_len;
769 			memcpy(p, cp->pe->name, pe_name_len);
770 			p += pe_name_len;
771 		}
772 	}
773 
774 	spin_unlock_bh(&ipvs->sync_buff_lock);
775 
776 control:
777 	/* synchronize its controller if it has */
778 	cp = cp->control;
779 	if (!cp)
780 		return;
781 	if (cp->flags & IP_VS_CONN_F_TEMPLATE)
782 		pkts = atomic_add_return(1, &cp->in_pkts);
783 	else
784 		pkts = sysctl_sync_threshold(ipvs);
785 	goto sloop;
786 }
787 
788 /*
789  *  fill_param used by version 1
790  */
791 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)792 ip_vs_conn_fill_param_sync(struct netns_ipvs *ipvs, int af, union ip_vs_sync_conn *sc,
793 			   struct ip_vs_conn_param *p,
794 			   __u8 *pe_data, unsigned int pe_data_len,
795 			   __u8 *pe_name, unsigned int pe_name_len)
796 {
797 #ifdef CONFIG_IP_VS_IPV6
798 	if (af == AF_INET6)
799 		ip_vs_conn_fill_param(ipvs, af, sc->v6.protocol,
800 				      (const union nf_inet_addr *)&sc->v6.caddr,
801 				      sc->v6.cport,
802 				      (const union nf_inet_addr *)&sc->v6.vaddr,
803 				      sc->v6.vport, p);
804 	else
805 #endif
806 		ip_vs_conn_fill_param(ipvs, af, sc->v4.protocol,
807 				      (const union nf_inet_addr *)&sc->v4.caddr,
808 				      sc->v4.cport,
809 				      (const union nf_inet_addr *)&sc->v4.vaddr,
810 				      sc->v4.vport, p);
811 	/* Handle pe data */
812 	if (pe_data_len) {
813 		if (pe_name_len) {
814 			char buff[IP_VS_PENAME_MAXLEN+1];
815 
816 			memcpy(buff, pe_name, pe_name_len);
817 			buff[pe_name_len]=0;
818 			p->pe = __ip_vs_pe_getbyname(buff);
819 			if (!p->pe) {
820 				IP_VS_DBG(3, "BACKUP, no %s engine found/loaded\n",
821 					     buff);
822 				return 1;
823 			}
824 		} else {
825 			IP_VS_ERR_RL("BACKUP, Invalid PE parameters\n");
826 			return 1;
827 		}
828 
829 		p->pe_data = kmemdup(pe_data, pe_data_len, GFP_ATOMIC);
830 		if (!p->pe_data) {
831 			module_put(p->pe->module);
832 			return -ENOMEM;
833 		}
834 		p->pe_data_len = pe_data_len;
835 	}
836 	return 0;
837 }
838 
839 /*
840  *  Connection Add / Update.
841  *  Common for version 0 and 1 reception of backup sync_conns.
842  *  Param: ...
843  *         timeout is in sec.
844  */
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)845 static void ip_vs_proc_conn(struct netns_ipvs *ipvs, struct ip_vs_conn_param *param,
846 			    unsigned int flags, unsigned int state,
847 			    unsigned int protocol, unsigned int type,
848 			    const union nf_inet_addr *daddr, __be16 dport,
849 			    unsigned long timeout, __u32 fwmark,
850 			    struct ip_vs_sync_conn_options *opt)
851 {
852 	struct ip_vs_dest *dest;
853 	struct ip_vs_conn *cp;
854 
855 	if (!(flags & IP_VS_CONN_F_TEMPLATE)) {
856 		cp = ip_vs_conn_in_get(param);
857 		if (cp && ((cp->dport != dport) ||
858 			   !ip_vs_addr_equal(cp->daf, &cp->daddr, daddr))) {
859 			if (!(flags & IP_VS_CONN_F_INACTIVE)) {
860 				ip_vs_conn_expire_now(cp);
861 				__ip_vs_conn_put(cp);
862 				cp = NULL;
863 			} else {
864 				/* This is the expiration message for the
865 				 * connection that was already replaced, so we
866 				 * just ignore it.
867 				 */
868 				__ip_vs_conn_put(cp);
869 				kfree(param->pe_data);
870 				return;
871 			}
872 		}
873 	} else {
874 		cp = ip_vs_ct_in_get(param);
875 	}
876 
877 	if (cp) {
878 		/* Free pe_data */
879 		kfree(param->pe_data);
880 
881 		dest = cp->dest;
882 		spin_lock_bh(&cp->lock);
883 		if ((cp->flags ^ flags) & IP_VS_CONN_F_INACTIVE &&
884 		    !(flags & IP_VS_CONN_F_TEMPLATE) && dest) {
885 			if (flags & IP_VS_CONN_F_INACTIVE) {
886 				atomic_dec(&dest->activeconns);
887 				atomic_inc(&dest->inactconns);
888 			} else {
889 				atomic_inc(&dest->activeconns);
890 				atomic_dec(&dest->inactconns);
891 			}
892 		}
893 		flags &= IP_VS_CONN_F_BACKUP_UPD_MASK;
894 		flags |= cp->flags & ~IP_VS_CONN_F_BACKUP_UPD_MASK;
895 		cp->flags = flags;
896 		spin_unlock_bh(&cp->lock);
897 		if (!dest)
898 			ip_vs_try_bind_dest(cp);
899 	} else {
900 		/*
901 		 * Find the appropriate destination for the connection.
902 		 * If it is not found the connection will remain unbound
903 		 * but still handled.
904 		 */
905 		rcu_read_lock();
906 		/* This function is only invoked by the synchronization
907 		 * code. We do not currently support heterogeneous pools
908 		 * with synchronization, so we can make the assumption that
909 		 * the svc_af is the same as the dest_af
910 		 */
911 		dest = ip_vs_find_dest(ipvs, type, type, daddr, dport,
912 				       param->vaddr, param->vport, protocol,
913 				       fwmark, flags);
914 
915 		cp = ip_vs_conn_new(param, type, daddr, dport, flags, dest,
916 				    fwmark);
917 		rcu_read_unlock();
918 		if (!cp) {
919 			kfree(param->pe_data);
920 			IP_VS_DBG(2, "BACKUP, add new conn. failed\n");
921 			return;
922 		}
923 		if (!(flags & IP_VS_CONN_F_TEMPLATE))
924 			kfree(param->pe_data);
925 	}
926 
927 	if (opt) {
928 		cp->in_seq = opt->in_seq;
929 		cp->out_seq = opt->out_seq;
930 	}
931 	atomic_set(&cp->in_pkts, sysctl_sync_threshold(ipvs));
932 	cp->state = state;
933 	cp->old_state = cp->state;
934 	/*
935 	 * For Ver 0 messages style
936 	 *  - Not possible to recover the right timeout for templates
937 	 *  - can not find the right fwmark
938 	 *    virtual service. If needed, we can do it for
939 	 *    non-fwmark persistent services.
940 	 * Ver 1 messages style.
941 	 *  - No problem.
942 	 */
943 	if (timeout) {
944 		if (timeout > MAX_SCHEDULE_TIMEOUT / HZ)
945 			timeout = MAX_SCHEDULE_TIMEOUT / HZ;
946 		cp->timeout = timeout*HZ;
947 	} else {
948 		struct ip_vs_proto_data *pd;
949 
950 		pd = ip_vs_proto_data_get(ipvs, protocol);
951 		if (!(flags & IP_VS_CONN_F_TEMPLATE) && pd && pd->timeout_table)
952 			cp->timeout = pd->timeout_table[state];
953 		else
954 			cp->timeout = (3*60*HZ);
955 	}
956 	ip_vs_conn_put(cp);
957 }
958 
959 /*
960  *  Process received multicast message for Version 0
961  */
ip_vs_process_message_v0(struct netns_ipvs * ipvs,const char * buffer,const size_t buflen)962 static void ip_vs_process_message_v0(struct netns_ipvs *ipvs, const char *buffer,
963 				     const size_t buflen)
964 {
965 	struct ip_vs_sync_mesg_v0 *m = (struct ip_vs_sync_mesg_v0 *)buffer;
966 	struct ip_vs_sync_conn_v0 *s;
967 	struct ip_vs_sync_conn_options *opt;
968 	struct ip_vs_protocol *pp;
969 	struct ip_vs_conn_param param;
970 	char *p;
971 	int i;
972 
973 	p = (char *)buffer + sizeof(struct ip_vs_sync_mesg_v0);
974 	for (i=0; i<m->nr_conns; i++) {
975 		unsigned int flags, state;
976 
977 		if (p + SIMPLE_CONN_SIZE > buffer+buflen) {
978 			IP_VS_ERR_RL("BACKUP v0, bogus conn\n");
979 			return;
980 		}
981 		s = (struct ip_vs_sync_conn_v0 *) p;
982 		flags = ntohs(s->flags) | IP_VS_CONN_F_SYNC;
983 		flags &= ~IP_VS_CONN_F_HASHED;
984 		if (flags & IP_VS_CONN_F_SEQ_MASK) {
985 			opt = (struct ip_vs_sync_conn_options *)&s[1];
986 			p += FULL_CONN_SIZE;
987 			if (p > buffer+buflen) {
988 				IP_VS_ERR_RL("BACKUP v0, Dropping buffer bogus conn options\n");
989 				return;
990 			}
991 		} else {
992 			opt = NULL;
993 			p += SIMPLE_CONN_SIZE;
994 		}
995 
996 		state = ntohs(s->state);
997 		if (!(flags & IP_VS_CONN_F_TEMPLATE)) {
998 			pp = ip_vs_proto_get(s->protocol);
999 			if (!pp) {
1000 				IP_VS_DBG(2, "BACKUP v0, Unsupported protocol %u\n",
1001 					s->protocol);
1002 				continue;
1003 			}
1004 			if (state >= pp->num_states) {
1005 				IP_VS_DBG(2, "BACKUP v0, Invalid %s state %u\n",
1006 					pp->name, state);
1007 				continue;
1008 			}
1009 		} else {
1010 			if (state >= IP_VS_CTPL_S_LAST)
1011 				IP_VS_DBG(7, "BACKUP v0, Invalid tpl state %u\n",
1012 					  state);
1013 		}
1014 
1015 		ip_vs_conn_fill_param(ipvs, AF_INET, s->protocol,
1016 				      (const union nf_inet_addr *)&s->caddr,
1017 				      s->cport,
1018 				      (const union nf_inet_addr *)&s->vaddr,
1019 				      s->vport, &param);
1020 
1021 		/* Send timeout as Zero */
1022 		ip_vs_proc_conn(ipvs, &param, flags, state, s->protocol, AF_INET,
1023 				(union nf_inet_addr *)&s->daddr, s->dport,
1024 				0, 0, opt);
1025 	}
1026 }
1027 
1028 /*
1029  * Handle options
1030  */
ip_vs_proc_seqopt(__u8 * p,unsigned int plen,__u32 * opt_flags,struct ip_vs_sync_conn_options * opt)1031 static inline int ip_vs_proc_seqopt(__u8 *p, unsigned int plen,
1032 				    __u32 *opt_flags,
1033 				    struct ip_vs_sync_conn_options *opt)
1034 {
1035 	struct ip_vs_sync_conn_options *topt;
1036 
1037 	topt = (struct ip_vs_sync_conn_options *)p;
1038 
1039 	if (plen != sizeof(struct ip_vs_sync_conn_options)) {
1040 		IP_VS_DBG(2, "BACKUP, bogus conn options length\n");
1041 		return -EINVAL;
1042 	}
1043 	if (*opt_flags & IPVS_OPT_F_SEQ_DATA) {
1044 		IP_VS_DBG(2, "BACKUP, conn options found twice\n");
1045 		return -EINVAL;
1046 	}
1047 	ntoh_seq(&topt->in_seq, &opt->in_seq);
1048 	ntoh_seq(&topt->out_seq, &opt->out_seq);
1049 	*opt_flags |= IPVS_OPT_F_SEQ_DATA;
1050 	return 0;
1051 }
1052 
ip_vs_proc_str(__u8 * p,unsigned int plen,unsigned int * data_len,__u8 ** data,unsigned int maxlen,__u32 * opt_flags,__u32 flag)1053 static int ip_vs_proc_str(__u8 *p, unsigned int plen, unsigned int *data_len,
1054 			  __u8 **data, unsigned int maxlen,
1055 			  __u32 *opt_flags, __u32 flag)
1056 {
1057 	if (plen > maxlen) {
1058 		IP_VS_DBG(2, "BACKUP, bogus par.data len > %d\n", maxlen);
1059 		return -EINVAL;
1060 	}
1061 	if (*opt_flags & flag) {
1062 		IP_VS_DBG(2, "BACKUP, Par.data found twice 0x%x\n", flag);
1063 		return -EINVAL;
1064 	}
1065 	*data_len = plen;
1066 	*data = p;
1067 	*opt_flags |= flag;
1068 	return 0;
1069 }
1070 /*
1071  *   Process a Version 1 sync. connection
1072  */
ip_vs_proc_sync_conn(struct netns_ipvs * ipvs,__u8 * p,__u8 * msg_end)1073 static inline int ip_vs_proc_sync_conn(struct netns_ipvs *ipvs, __u8 *p, __u8 *msg_end)
1074 {
1075 	struct ip_vs_sync_conn_options opt;
1076 	union  ip_vs_sync_conn *s;
1077 	struct ip_vs_protocol *pp;
1078 	struct ip_vs_conn_param param;
1079 	__u32 flags;
1080 	unsigned int af, state, pe_data_len=0, pe_name_len=0;
1081 	__u8 *pe_data=NULL, *pe_name=NULL;
1082 	__u32 opt_flags=0;
1083 	int retc=0;
1084 
1085 	s = (union ip_vs_sync_conn *) p;
1086 
1087 	if (s->v6.type & STYPE_F_INET6) {
1088 #ifdef CONFIG_IP_VS_IPV6
1089 		af = AF_INET6;
1090 		p += sizeof(struct ip_vs_sync_v6);
1091 #else
1092 		IP_VS_DBG(3,"BACKUP, IPv6 msg received, and IPVS is not compiled for IPv6\n");
1093 		retc = 10;
1094 		goto out;
1095 #endif
1096 	} else if (!s->v4.type) {
1097 		af = AF_INET;
1098 		p += sizeof(struct ip_vs_sync_v4);
1099 	} else {
1100 		return -10;
1101 	}
1102 	if (p > msg_end)
1103 		return -20;
1104 
1105 	/* Process optional params check Type & Len. */
1106 	while (p < msg_end) {
1107 		int ptype;
1108 		int plen;
1109 
1110 		if (p+2 > msg_end)
1111 			return -30;
1112 		ptype = *(p++);
1113 		plen  = *(p++);
1114 
1115 		if (!plen || ((p + plen) > msg_end))
1116 			return -40;
1117 		/* Handle seq option  p = param data */
1118 		switch (ptype & ~IPVS_OPT_F_PARAM) {
1119 		case IPVS_OPT_SEQ_DATA:
1120 			if (ip_vs_proc_seqopt(p, plen, &opt_flags, &opt))
1121 				return -50;
1122 			break;
1123 
1124 		case IPVS_OPT_PE_DATA:
1125 			if (ip_vs_proc_str(p, plen, &pe_data_len, &pe_data,
1126 					   IP_VS_PEDATA_MAXLEN, &opt_flags,
1127 					   IPVS_OPT_F_PE_DATA))
1128 				return -60;
1129 			break;
1130 
1131 		case IPVS_OPT_PE_NAME:
1132 			if (ip_vs_proc_str(p, plen,&pe_name_len, &pe_name,
1133 					   IP_VS_PENAME_MAXLEN, &opt_flags,
1134 					   IPVS_OPT_F_PE_NAME))
1135 				return -70;
1136 			break;
1137 
1138 		default:
1139 			/* Param data mandatory ? */
1140 			if (!(ptype & IPVS_OPT_F_PARAM)) {
1141 				IP_VS_DBG(3, "BACKUP, Unknown mandatory param %d found\n",
1142 					  ptype & ~IPVS_OPT_F_PARAM);
1143 				retc = 20;
1144 				goto out;
1145 			}
1146 		}
1147 		p += plen;  /* Next option */
1148 	}
1149 
1150 	/* Get flags and Mask off unsupported */
1151 	flags  = ntohl(s->v4.flags) & IP_VS_CONN_F_BACKUP_MASK;
1152 	flags |= IP_VS_CONN_F_SYNC;
1153 	state = ntohs(s->v4.state);
1154 
1155 	if (!(flags & IP_VS_CONN_F_TEMPLATE)) {
1156 		pp = ip_vs_proto_get(s->v4.protocol);
1157 		if (!pp) {
1158 			IP_VS_DBG(3,"BACKUP, Unsupported protocol %u\n",
1159 				s->v4.protocol);
1160 			retc = 30;
1161 			goto out;
1162 		}
1163 		if (state >= pp->num_states) {
1164 			IP_VS_DBG(3, "BACKUP, Invalid %s state %u\n",
1165 				pp->name, state);
1166 			retc = 40;
1167 			goto out;
1168 		}
1169 	} else {
1170 		if (state >= IP_VS_CTPL_S_LAST)
1171 			IP_VS_DBG(7, "BACKUP, Invalid tpl state %u\n",
1172 				  state);
1173 	}
1174 	if (ip_vs_conn_fill_param_sync(ipvs, af, s, &param, pe_data,
1175 				       pe_data_len, pe_name, pe_name_len)) {
1176 		retc = 50;
1177 		goto out;
1178 	}
1179 	/* If only IPv4, just silent skip IPv6 */
1180 	if (af == AF_INET)
1181 		ip_vs_proc_conn(ipvs, &param, flags, state, s->v4.protocol, af,
1182 				(union nf_inet_addr *)&s->v4.daddr, s->v4.dport,
1183 				ntohl(s->v4.timeout), ntohl(s->v4.fwmark),
1184 				(opt_flags & IPVS_OPT_F_SEQ_DATA ? &opt : NULL)
1185 				);
1186 #ifdef CONFIG_IP_VS_IPV6
1187 	else
1188 		ip_vs_proc_conn(ipvs, &param, flags, state, s->v6.protocol, af,
1189 				(union nf_inet_addr *)&s->v6.daddr, s->v6.dport,
1190 				ntohl(s->v6.timeout), ntohl(s->v6.fwmark),
1191 				(opt_flags & IPVS_OPT_F_SEQ_DATA ? &opt : NULL)
1192 				);
1193 #endif
1194 	ip_vs_pe_put(param.pe);
1195 	return 0;
1196 	/* Error exit */
1197 out:
1198 	IP_VS_DBG(2, "BACKUP, Single msg dropped err:%d\n", retc);
1199 	return retc;
1200 
1201 }
1202 /*
1203  *      Process received multicast message and create the corresponding
1204  *      ip_vs_conn entries.
1205  *      Handles Version 0 & 1
1206  */
ip_vs_process_message(struct netns_ipvs * ipvs,__u8 * buffer,const size_t buflen)1207 static void ip_vs_process_message(struct netns_ipvs *ipvs, __u8 *buffer,
1208 				  const size_t buflen)
1209 {
1210 	struct ip_vs_sync_mesg *m2 = (struct ip_vs_sync_mesg *)buffer;
1211 	__u8 *p, *msg_end;
1212 	int i, nr_conns;
1213 
1214 	if (buflen < sizeof(struct ip_vs_sync_mesg_v0)) {
1215 		IP_VS_DBG(2, "BACKUP, message header too short\n");
1216 		return;
1217 	}
1218 
1219 	if (buflen != ntohs(m2->size)) {
1220 		IP_VS_DBG(2, "BACKUP, bogus message size\n");
1221 		return;
1222 	}
1223 	/* SyncID sanity check */
1224 	if (ipvs->bcfg.syncid != 0 && m2->syncid != ipvs->bcfg.syncid) {
1225 		IP_VS_DBG(7, "BACKUP, Ignoring syncid = %d\n", m2->syncid);
1226 		return;
1227 	}
1228 	/* Handle version 1  message */
1229 	if ((m2->version == SYNC_PROTO_VER) && (m2->reserved == 0)
1230 	    && (m2->spare == 0)) {
1231 
1232 		msg_end = buffer + sizeof(struct ip_vs_sync_mesg);
1233 		nr_conns = m2->nr_conns;
1234 
1235 		for (i=0; i<nr_conns; i++) {
1236 			union ip_vs_sync_conn *s;
1237 			unsigned int size;
1238 			int retc;
1239 
1240 			p = msg_end;
1241 			if (p + sizeof(s->v4) > buffer+buflen) {
1242 				IP_VS_ERR_RL("BACKUP, Dropping buffer, to small\n");
1243 				return;
1244 			}
1245 			s = (union ip_vs_sync_conn *)p;
1246 			size = ntohs(s->v4.ver_size) & SVER_MASK;
1247 			msg_end = p + size;
1248 			/* Basic sanity checks */
1249 			if (msg_end  > buffer+buflen) {
1250 				IP_VS_ERR_RL("BACKUP, Dropping buffer, msg > buffer\n");
1251 				return;
1252 			}
1253 			if (ntohs(s->v4.ver_size) >> SVER_SHIFT) {
1254 				IP_VS_ERR_RL("BACKUP, Dropping buffer, Unknown version %d\n",
1255 					      ntohs(s->v4.ver_size) >> SVER_SHIFT);
1256 				return;
1257 			}
1258 			/* Process a single sync_conn */
1259 			retc = ip_vs_proc_sync_conn(ipvs, p, msg_end);
1260 			if (retc < 0) {
1261 				IP_VS_ERR_RL("BACKUP, Dropping buffer, Err: %d in decoding\n",
1262 					     retc);
1263 				return;
1264 			}
1265 			/* Make sure we have 32 bit alignment */
1266 			msg_end = p + ((size + 3) & ~3);
1267 		}
1268 	} else {
1269 		/* Old type of message */
1270 		ip_vs_process_message_v0(ipvs, buffer, buflen);
1271 		return;
1272 	}
1273 }
1274 
1275 
1276 /*
1277  *      Setup sndbuf (mode=1) or rcvbuf (mode=0)
1278  */
set_sock_size(struct sock * sk,int mode,int val)1279 static void set_sock_size(struct sock *sk, int mode, int val)
1280 {
1281 	/* setsockopt(sock, SOL_SOCKET, SO_SNDBUF, &val, sizeof(val)); */
1282 	/* setsockopt(sock, SOL_SOCKET, SO_RCVBUF, &val, sizeof(val)); */
1283 	lock_sock(sk);
1284 	if (mode) {
1285 		val = clamp_t(int, val, (SOCK_MIN_SNDBUF + 1) / 2,
1286 			      sysctl_wmem_max);
1287 		sk->sk_sndbuf = val * 2;
1288 		sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
1289 	} else {
1290 		val = clamp_t(int, val, (SOCK_MIN_RCVBUF + 1) / 2,
1291 			      sysctl_rmem_max);
1292 		sk->sk_rcvbuf = val * 2;
1293 		sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
1294 	}
1295 	release_sock(sk);
1296 }
1297 
1298 /*
1299  *      Setup loopback of outgoing multicasts on a sending socket
1300  */
set_mcast_loop(struct sock * sk,u_char loop)1301 static void set_mcast_loop(struct sock *sk, u_char loop)
1302 {
1303 	struct inet_sock *inet = inet_sk(sk);
1304 
1305 	/* setsockopt(sock, SOL_IP, IP_MULTICAST_LOOP, &loop, sizeof(loop)); */
1306 	lock_sock(sk);
1307 	inet->mc_loop = loop ? 1 : 0;
1308 #ifdef CONFIG_IP_VS_IPV6
1309 	if (sk->sk_family == AF_INET6) {
1310 		struct ipv6_pinfo *np = inet6_sk(sk);
1311 
1312 		/* IPV6_MULTICAST_LOOP */
1313 		np->mc_loop = loop ? 1 : 0;
1314 	}
1315 #endif
1316 	release_sock(sk);
1317 }
1318 
1319 /*
1320  *      Specify TTL for outgoing multicasts on a sending socket
1321  */
set_mcast_ttl(struct sock * sk,u_char ttl)1322 static void set_mcast_ttl(struct sock *sk, u_char ttl)
1323 {
1324 	struct inet_sock *inet = inet_sk(sk);
1325 
1326 	/* setsockopt(sock, SOL_IP, IP_MULTICAST_TTL, &ttl, sizeof(ttl)); */
1327 	lock_sock(sk);
1328 	inet->mc_ttl = ttl;
1329 #ifdef CONFIG_IP_VS_IPV6
1330 	if (sk->sk_family == AF_INET6) {
1331 		struct ipv6_pinfo *np = inet6_sk(sk);
1332 
1333 		/* IPV6_MULTICAST_HOPS */
1334 		np->mcast_hops = ttl;
1335 	}
1336 #endif
1337 	release_sock(sk);
1338 }
1339 
1340 /* Control fragmentation of messages */
set_mcast_pmtudisc(struct sock * sk,int val)1341 static void set_mcast_pmtudisc(struct sock *sk, int val)
1342 {
1343 	struct inet_sock *inet = inet_sk(sk);
1344 
1345 	/* setsockopt(sock, SOL_IP, IP_MTU_DISCOVER, &val, sizeof(val)); */
1346 	lock_sock(sk);
1347 	inet->pmtudisc = val;
1348 #ifdef CONFIG_IP_VS_IPV6
1349 	if (sk->sk_family == AF_INET6) {
1350 		struct ipv6_pinfo *np = inet6_sk(sk);
1351 
1352 		/* IPV6_MTU_DISCOVER */
1353 		np->pmtudisc = val;
1354 	}
1355 #endif
1356 	release_sock(sk);
1357 }
1358 
1359 /*
1360  *      Specifiy default interface for outgoing multicasts
1361  */
set_mcast_if(struct sock * sk,struct net_device * dev)1362 static int set_mcast_if(struct sock *sk, struct net_device *dev)
1363 {
1364 	struct inet_sock *inet = inet_sk(sk);
1365 
1366 	if (sk->sk_bound_dev_if && dev->ifindex != sk->sk_bound_dev_if)
1367 		return -EINVAL;
1368 
1369 	lock_sock(sk);
1370 	inet->mc_index = dev->ifindex;
1371 	/*  inet->mc_addr  = 0; */
1372 #ifdef CONFIG_IP_VS_IPV6
1373 	if (sk->sk_family == AF_INET6) {
1374 		struct ipv6_pinfo *np = inet6_sk(sk);
1375 
1376 		/* IPV6_MULTICAST_IF */
1377 		np->mcast_oif = dev->ifindex;
1378 	}
1379 #endif
1380 	release_sock(sk);
1381 
1382 	return 0;
1383 }
1384 
1385 
1386 /*
1387  *      Join a multicast group.
1388  *      the group is specified by a class D multicast address 224.0.0.0/8
1389  *      in the in_addr structure passed in as a parameter.
1390  */
1391 static int
join_mcast_group(struct sock * sk,struct in_addr * addr,struct net_device * dev)1392 join_mcast_group(struct sock *sk, struct in_addr *addr, struct net_device *dev)
1393 {
1394 	struct ip_mreqn mreq;
1395 	int ret;
1396 
1397 	memset(&mreq, 0, sizeof(mreq));
1398 	memcpy(&mreq.imr_multiaddr, addr, sizeof(struct in_addr));
1399 
1400 	if (sk->sk_bound_dev_if && dev->ifindex != sk->sk_bound_dev_if)
1401 		return -EINVAL;
1402 
1403 	mreq.imr_ifindex = dev->ifindex;
1404 
1405 	lock_sock(sk);
1406 	ret = ip_mc_join_group(sk, &mreq);
1407 	release_sock(sk);
1408 
1409 	return ret;
1410 }
1411 
1412 #ifdef CONFIG_IP_VS_IPV6
join_mcast_group6(struct sock * sk,struct in6_addr * addr,struct net_device * dev)1413 static int join_mcast_group6(struct sock *sk, struct in6_addr *addr,
1414 			     struct net_device *dev)
1415 {
1416 	int ret;
1417 
1418 	if (sk->sk_bound_dev_if && dev->ifindex != sk->sk_bound_dev_if)
1419 		return -EINVAL;
1420 
1421 	lock_sock(sk);
1422 	ret = ipv6_sock_mc_join(sk, dev->ifindex, addr);
1423 	release_sock(sk);
1424 
1425 	return ret;
1426 }
1427 #endif
1428 
bind_mcastif_addr(struct socket * sock,struct net_device * dev)1429 static int bind_mcastif_addr(struct socket *sock, struct net_device *dev)
1430 {
1431 	__be32 addr;
1432 	struct sockaddr_in sin;
1433 
1434 	addr = inet_select_addr(dev, 0, RT_SCOPE_UNIVERSE);
1435 	if (!addr)
1436 		pr_err("You probably need to specify IP address on "
1437 		       "multicast interface.\n");
1438 
1439 	IP_VS_DBG(7, "binding socket with (%s) %pI4\n",
1440 		  dev->name, &addr);
1441 
1442 	/* Now bind the socket with the address of multicast interface */
1443 	sin.sin_family	     = AF_INET;
1444 	sin.sin_addr.s_addr  = addr;
1445 	sin.sin_port         = 0;
1446 
1447 	return kernel_bind(sock, (struct sockaddr *)&sin, sizeof(sin));
1448 }
1449 
get_mcast_sockaddr(union ipvs_sockaddr * sa,int * salen,struct ipvs_sync_daemon_cfg * c,int id)1450 static void get_mcast_sockaddr(union ipvs_sockaddr *sa, int *salen,
1451 			       struct ipvs_sync_daemon_cfg *c, int id)
1452 {
1453 	if (AF_INET6 == c->mcast_af) {
1454 		sa->in6 = (struct sockaddr_in6) {
1455 			.sin6_family = AF_INET6,
1456 			.sin6_port = htons(c->mcast_port + id),
1457 		};
1458 		sa->in6.sin6_addr = c->mcast_group.in6;
1459 		*salen = sizeof(sa->in6);
1460 	} else {
1461 		sa->in = (struct sockaddr_in) {
1462 			.sin_family = AF_INET,
1463 			.sin_port = htons(c->mcast_port + id),
1464 		};
1465 		sa->in.sin_addr = c->mcast_group.in;
1466 		*salen = sizeof(sa->in);
1467 	}
1468 }
1469 
1470 /*
1471  *      Set up sending multicast socket over UDP
1472  */
make_send_sock(struct netns_ipvs * ipvs,int id,struct net_device * dev,struct socket ** sock_ret)1473 static int make_send_sock(struct netns_ipvs *ipvs, int id,
1474 			  struct net_device *dev, struct socket **sock_ret)
1475 {
1476 	/* multicast addr */
1477 	union ipvs_sockaddr mcast_addr;
1478 	struct socket *sock;
1479 	int result, salen;
1480 
1481 	/* First create a socket */
1482 	result = sock_create_kern(ipvs->net, ipvs->mcfg.mcast_af, SOCK_DGRAM,
1483 				  IPPROTO_UDP, &sock);
1484 	if (result < 0) {
1485 		pr_err("Error during creation of socket; terminating\n");
1486 		goto error;
1487 	}
1488 	*sock_ret = sock;
1489 	result = set_mcast_if(sock->sk, dev);
1490 	if (result < 0) {
1491 		pr_err("Error setting outbound mcast interface\n");
1492 		goto error;
1493 	}
1494 
1495 	set_mcast_loop(sock->sk, 0);
1496 	set_mcast_ttl(sock->sk, ipvs->mcfg.mcast_ttl);
1497 	/* Allow fragmentation if MTU changes */
1498 	set_mcast_pmtudisc(sock->sk, IP_PMTUDISC_DONT);
1499 	result = sysctl_sync_sock_size(ipvs);
1500 	if (result > 0)
1501 		set_sock_size(sock->sk, 1, result);
1502 
1503 	if (AF_INET == ipvs->mcfg.mcast_af)
1504 		result = bind_mcastif_addr(sock, dev);
1505 	else
1506 		result = 0;
1507 	if (result < 0) {
1508 		pr_err("Error binding address of the mcast interface\n");
1509 		goto error;
1510 	}
1511 
1512 	get_mcast_sockaddr(&mcast_addr, &salen, &ipvs->mcfg, id);
1513 	result = kernel_connect(sock, (struct sockaddr *)&mcast_addr,
1514 				salen, 0);
1515 	if (result < 0) {
1516 		pr_err("Error connecting to the multicast addr\n");
1517 		goto error;
1518 	}
1519 
1520 	return 0;
1521 
1522 error:
1523 	return result;
1524 }
1525 
1526 
1527 /*
1528  *      Set up receiving multicast socket over UDP
1529  */
make_receive_sock(struct netns_ipvs * ipvs,int id,struct net_device * dev,struct socket ** sock_ret)1530 static int make_receive_sock(struct netns_ipvs *ipvs, int id,
1531 			     struct net_device *dev, struct socket **sock_ret)
1532 {
1533 	/* multicast addr */
1534 	union ipvs_sockaddr mcast_addr;
1535 	struct socket *sock;
1536 	int result, salen;
1537 
1538 	/* First create a socket */
1539 	result = sock_create_kern(ipvs->net, ipvs->bcfg.mcast_af, SOCK_DGRAM,
1540 				  IPPROTO_UDP, &sock);
1541 	if (result < 0) {
1542 		pr_err("Error during creation of socket; terminating\n");
1543 		goto error;
1544 	}
1545 	*sock_ret = sock;
1546 	/* it is equivalent to the REUSEADDR option in user-space */
1547 	sock->sk->sk_reuse = SK_CAN_REUSE;
1548 	result = sysctl_sync_sock_size(ipvs);
1549 	if (result > 0)
1550 		set_sock_size(sock->sk, 0, result);
1551 
1552 	get_mcast_sockaddr(&mcast_addr, &salen, &ipvs->bcfg, id);
1553 	sock->sk->sk_bound_dev_if = dev->ifindex;
1554 	result = kernel_bind(sock, (struct sockaddr *)&mcast_addr, salen);
1555 	if (result < 0) {
1556 		pr_err("Error binding to the multicast addr\n");
1557 		goto error;
1558 	}
1559 
1560 	/* join the multicast group */
1561 #ifdef CONFIG_IP_VS_IPV6
1562 	if (ipvs->bcfg.mcast_af == AF_INET6)
1563 		result = join_mcast_group6(sock->sk, &mcast_addr.in6.sin6_addr,
1564 					   dev);
1565 	else
1566 #endif
1567 		result = join_mcast_group(sock->sk, &mcast_addr.in.sin_addr,
1568 					  dev);
1569 	if (result < 0) {
1570 		pr_err("Error joining to the multicast group\n");
1571 		goto error;
1572 	}
1573 
1574 	return 0;
1575 
1576 error:
1577 	return result;
1578 }
1579 
1580 
1581 static int
ip_vs_send_async(struct socket * sock,const char * buffer,const size_t length)1582 ip_vs_send_async(struct socket *sock, const char *buffer, const size_t length)
1583 {
1584 	struct msghdr	msg = {.msg_flags = MSG_DONTWAIT|MSG_NOSIGNAL};
1585 	struct kvec	iov;
1586 	int		len;
1587 
1588 	EnterFunction(7);
1589 	iov.iov_base     = (void *)buffer;
1590 	iov.iov_len      = length;
1591 
1592 	len = kernel_sendmsg(sock, &msg, &iov, 1, (size_t)(length));
1593 
1594 	LeaveFunction(7);
1595 	return len;
1596 }
1597 
1598 static int
ip_vs_send_sync_msg(struct socket * sock,struct ip_vs_sync_mesg * msg)1599 ip_vs_send_sync_msg(struct socket *sock, struct ip_vs_sync_mesg *msg)
1600 {
1601 	int msize;
1602 	int ret;
1603 
1604 	msize = ntohs(msg->size);
1605 
1606 	ret = ip_vs_send_async(sock, (char *)msg, msize);
1607 	if (ret >= 0 || ret == -EAGAIN)
1608 		return ret;
1609 	pr_err("ip_vs_send_async error %d\n", ret);
1610 	return 0;
1611 }
1612 
1613 static int
ip_vs_receive(struct socket * sock,char * buffer,const size_t buflen)1614 ip_vs_receive(struct socket *sock, char *buffer, const size_t buflen)
1615 {
1616 	struct msghdr		msg = {NULL,};
1617 	struct kvec		iov = {buffer, buflen};
1618 	int			len;
1619 
1620 	EnterFunction(7);
1621 
1622 	/* Receive a packet */
1623 	iov_iter_kvec(&msg.msg_iter, READ, &iov, 1, buflen);
1624 	len = sock_recvmsg(sock, &msg, MSG_DONTWAIT);
1625 	if (len < 0)
1626 		return len;
1627 
1628 	LeaveFunction(7);
1629 	return len;
1630 }
1631 
1632 /* Wakeup the master thread for sending */
master_wakeup_work_handler(struct work_struct * work)1633 static void master_wakeup_work_handler(struct work_struct *work)
1634 {
1635 	struct ipvs_master_sync_state *ms =
1636 		container_of(work, struct ipvs_master_sync_state,
1637 			     master_wakeup_work.work);
1638 	struct netns_ipvs *ipvs = ms->ipvs;
1639 
1640 	spin_lock_bh(&ipvs->sync_lock);
1641 	if (ms->sync_queue_len &&
1642 	    ms->sync_queue_delay < IPVS_SYNC_WAKEUP_RATE) {
1643 		int id = (int)(ms - ipvs->ms);
1644 
1645 		ms->sync_queue_delay = IPVS_SYNC_WAKEUP_RATE;
1646 		wake_up_process(ipvs->master_tinfo[id].task);
1647 	}
1648 	spin_unlock_bh(&ipvs->sync_lock);
1649 }
1650 
1651 /* Get next buffer to send */
1652 static inline struct ip_vs_sync_buff *
next_sync_buff(struct netns_ipvs * ipvs,struct ipvs_master_sync_state * ms)1653 next_sync_buff(struct netns_ipvs *ipvs, struct ipvs_master_sync_state *ms)
1654 {
1655 	struct ip_vs_sync_buff *sb;
1656 
1657 	sb = sb_dequeue(ipvs, ms);
1658 	if (sb)
1659 		return sb;
1660 	/* Do not delay entries in buffer for more than 2 seconds */
1661 	return get_curr_sync_buff(ipvs, ms, IPVS_SYNC_FLUSH_TIME);
1662 }
1663 
sync_thread_master(void * data)1664 static int sync_thread_master(void *data)
1665 {
1666 	struct ip_vs_sync_thread_data *tinfo = data;
1667 	struct netns_ipvs *ipvs = tinfo->ipvs;
1668 	struct ipvs_master_sync_state *ms = &ipvs->ms[tinfo->id];
1669 	struct sock *sk = tinfo->sock->sk;
1670 	struct ip_vs_sync_buff *sb;
1671 
1672 	pr_info("sync thread started: state = MASTER, mcast_ifn = %s, "
1673 		"syncid = %d, id = %d\n",
1674 		ipvs->mcfg.mcast_ifn, ipvs->mcfg.syncid, tinfo->id);
1675 
1676 	for (;;) {
1677 		sb = next_sync_buff(ipvs, ms);
1678 		if (unlikely(kthread_should_stop()))
1679 			break;
1680 		if (!sb) {
1681 			schedule_timeout(IPVS_SYNC_CHECK_PERIOD);
1682 			continue;
1683 		}
1684 		while (ip_vs_send_sync_msg(tinfo->sock, sb->mesg) < 0) {
1685 			/* (Ab)use interruptible sleep to avoid increasing
1686 			 * the load avg.
1687 			 */
1688 			__wait_event_interruptible(*sk_sleep(sk),
1689 						   sock_writeable(sk) ||
1690 						   kthread_should_stop());
1691 			if (unlikely(kthread_should_stop()))
1692 				goto done;
1693 		}
1694 		ip_vs_sync_buff_release(sb);
1695 	}
1696 
1697 done:
1698 	__set_current_state(TASK_RUNNING);
1699 	if (sb)
1700 		ip_vs_sync_buff_release(sb);
1701 
1702 	/* clean up the sync_buff queue */
1703 	while ((sb = sb_dequeue(ipvs, ms)))
1704 		ip_vs_sync_buff_release(sb);
1705 	__set_current_state(TASK_RUNNING);
1706 
1707 	/* clean up the current sync_buff */
1708 	sb = get_curr_sync_buff(ipvs, ms, 0);
1709 	if (sb)
1710 		ip_vs_sync_buff_release(sb);
1711 
1712 	return 0;
1713 }
1714 
1715 
sync_thread_backup(void * data)1716 static int sync_thread_backup(void *data)
1717 {
1718 	struct ip_vs_sync_thread_data *tinfo = data;
1719 	struct netns_ipvs *ipvs = tinfo->ipvs;
1720 	struct sock *sk = tinfo->sock->sk;
1721 	struct udp_sock *up = udp_sk(sk);
1722 	int len;
1723 
1724 	pr_info("sync thread started: state = BACKUP, mcast_ifn = %s, "
1725 		"syncid = %d, id = %d\n",
1726 		ipvs->bcfg.mcast_ifn, ipvs->bcfg.syncid, tinfo->id);
1727 
1728 	while (!kthread_should_stop()) {
1729 		wait_event_interruptible(*sk_sleep(sk),
1730 					 !skb_queue_empty_lockless(&sk->sk_receive_queue) ||
1731 					 !skb_queue_empty_lockless(&up->reader_queue) ||
1732 					 kthread_should_stop());
1733 
1734 		/* do we have data now? */
1735 		while (!skb_queue_empty_lockless(&sk->sk_receive_queue) ||
1736 		       !skb_queue_empty_lockless(&up->reader_queue)) {
1737 			len = ip_vs_receive(tinfo->sock, tinfo->buf,
1738 					ipvs->bcfg.sync_maxlen);
1739 			if (len <= 0) {
1740 				if (len != -EAGAIN)
1741 					pr_err("receiving message error\n");
1742 				break;
1743 			}
1744 
1745 			ip_vs_process_message(ipvs, tinfo->buf, len);
1746 		}
1747 	}
1748 
1749 	return 0;
1750 }
1751 
1752 
start_sync_thread(struct netns_ipvs * ipvs,struct ipvs_sync_daemon_cfg * c,int state)1753 int start_sync_thread(struct netns_ipvs *ipvs, struct ipvs_sync_daemon_cfg *c,
1754 		      int state)
1755 {
1756 	struct ip_vs_sync_thread_data *ti = NULL, *tinfo;
1757 	struct task_struct *task;
1758 	struct net_device *dev;
1759 	char *name;
1760 	int (*threadfn)(void *data);
1761 	int id = 0, count, hlen;
1762 	int result = -ENOMEM;
1763 	u16 mtu, min_mtu;
1764 
1765 	IP_VS_DBG(7, "%s(): pid %d\n", __func__, task_pid_nr(current));
1766 	IP_VS_DBG(7, "Each ip_vs_sync_conn entry needs %zd bytes\n",
1767 		  sizeof(struct ip_vs_sync_conn_v0));
1768 
1769 	/* increase the module use count */
1770 	if (!ip_vs_use_count_inc())
1771 		return -ENOPROTOOPT;
1772 
1773 	/* Do not hold one mutex and then to block on another */
1774 	for (;;) {
1775 		rtnl_lock();
1776 		if (mutex_trylock(&ipvs->sync_mutex))
1777 			break;
1778 		rtnl_unlock();
1779 		mutex_lock(&ipvs->sync_mutex);
1780 		if (rtnl_trylock())
1781 			break;
1782 		mutex_unlock(&ipvs->sync_mutex);
1783 	}
1784 
1785 	if (!ipvs->sync_state) {
1786 		count = clamp(sysctl_sync_ports(ipvs), 1, IPVS_SYNC_PORTS_MAX);
1787 		ipvs->threads_mask = count - 1;
1788 	} else
1789 		count = ipvs->threads_mask + 1;
1790 
1791 	if (c->mcast_af == AF_UNSPEC) {
1792 		c->mcast_af = AF_INET;
1793 		c->mcast_group.ip = cpu_to_be32(IP_VS_SYNC_GROUP);
1794 	}
1795 	if (!c->mcast_port)
1796 		c->mcast_port = IP_VS_SYNC_PORT;
1797 	if (!c->mcast_ttl)
1798 		c->mcast_ttl = 1;
1799 
1800 	dev = __dev_get_by_name(ipvs->net, c->mcast_ifn);
1801 	if (!dev) {
1802 		pr_err("Unknown mcast interface: %s\n", c->mcast_ifn);
1803 		result = -ENODEV;
1804 		goto out_early;
1805 	}
1806 	hlen = (AF_INET6 == c->mcast_af) ?
1807 	       sizeof(struct ipv6hdr) + sizeof(struct udphdr) :
1808 	       sizeof(struct iphdr) + sizeof(struct udphdr);
1809 	mtu = (state == IP_VS_STATE_BACKUP) ?
1810 		  clamp(dev->mtu, 1500U, 65535U) : 1500U;
1811 	min_mtu = (state == IP_VS_STATE_BACKUP) ? 1024 : 1;
1812 
1813 	if (c->sync_maxlen)
1814 		c->sync_maxlen = clamp_t(unsigned int,
1815 					 c->sync_maxlen, min_mtu,
1816 					 65535 - hlen);
1817 	else
1818 		c->sync_maxlen = mtu - hlen;
1819 
1820 	if (state == IP_VS_STATE_MASTER) {
1821 		result = -EEXIST;
1822 		if (ipvs->ms)
1823 			goto out_early;
1824 
1825 		ipvs->mcfg = *c;
1826 		name = "ipvs-m:%d:%d";
1827 		threadfn = sync_thread_master;
1828 	} else if (state == IP_VS_STATE_BACKUP) {
1829 		result = -EEXIST;
1830 		if (ipvs->backup_tinfo)
1831 			goto out_early;
1832 
1833 		ipvs->bcfg = *c;
1834 		name = "ipvs-b:%d:%d";
1835 		threadfn = sync_thread_backup;
1836 	} else {
1837 		result = -EINVAL;
1838 		goto out_early;
1839 	}
1840 
1841 	if (state == IP_VS_STATE_MASTER) {
1842 		struct ipvs_master_sync_state *ms;
1843 
1844 		result = -ENOMEM;
1845 		ipvs->ms = kcalloc(count, sizeof(ipvs->ms[0]), GFP_KERNEL);
1846 		if (!ipvs->ms)
1847 			goto out;
1848 		ms = ipvs->ms;
1849 		for (id = 0; id < count; id++, ms++) {
1850 			INIT_LIST_HEAD(&ms->sync_queue);
1851 			ms->sync_queue_len = 0;
1852 			ms->sync_queue_delay = 0;
1853 			INIT_DELAYED_WORK(&ms->master_wakeup_work,
1854 					  master_wakeup_work_handler);
1855 			ms->ipvs = ipvs;
1856 		}
1857 	}
1858 	result = -ENOMEM;
1859 	ti = kcalloc(count, sizeof(struct ip_vs_sync_thread_data),
1860 		     GFP_KERNEL);
1861 	if (!ti)
1862 		goto out;
1863 
1864 	for (id = 0; id < count; id++) {
1865 		tinfo = &ti[id];
1866 		tinfo->ipvs = ipvs;
1867 		if (state == IP_VS_STATE_BACKUP) {
1868 			result = -ENOMEM;
1869 			tinfo->buf = kmalloc(ipvs->bcfg.sync_maxlen,
1870 					     GFP_KERNEL);
1871 			if (!tinfo->buf)
1872 				goto out;
1873 		}
1874 		tinfo->id = id;
1875 		if (state == IP_VS_STATE_MASTER)
1876 			result = make_send_sock(ipvs, id, dev, &tinfo->sock);
1877 		else
1878 			result = make_receive_sock(ipvs, id, dev, &tinfo->sock);
1879 		if (result < 0)
1880 			goto out;
1881 
1882 		task = kthread_run(threadfn, tinfo, name, ipvs->gen, id);
1883 		if (IS_ERR(task)) {
1884 			result = PTR_ERR(task);
1885 			goto out;
1886 		}
1887 		tinfo->task = task;
1888 	}
1889 
1890 	/* mark as active */
1891 
1892 	if (state == IP_VS_STATE_MASTER)
1893 		ipvs->master_tinfo = ti;
1894 	else
1895 		ipvs->backup_tinfo = ti;
1896 	spin_lock_bh(&ipvs->sync_buff_lock);
1897 	ipvs->sync_state |= state;
1898 	spin_unlock_bh(&ipvs->sync_buff_lock);
1899 
1900 	mutex_unlock(&ipvs->sync_mutex);
1901 	rtnl_unlock();
1902 
1903 	return 0;
1904 
1905 out:
1906 	/* We do not need RTNL lock anymore, release it here so that
1907 	 * sock_release below can use rtnl_lock to leave the mcast group.
1908 	 */
1909 	rtnl_unlock();
1910 	id = min(id, count - 1);
1911 	if (ti) {
1912 		for (tinfo = ti + id; tinfo >= ti; tinfo--) {
1913 			if (tinfo->task)
1914 				kthread_stop(tinfo->task);
1915 		}
1916 	}
1917 	if (!(ipvs->sync_state & IP_VS_STATE_MASTER)) {
1918 		kfree(ipvs->ms);
1919 		ipvs->ms = NULL;
1920 	}
1921 	mutex_unlock(&ipvs->sync_mutex);
1922 
1923 	/* No more mutexes, release socks */
1924 	if (ti) {
1925 		for (tinfo = ti + id; tinfo >= ti; tinfo--) {
1926 			if (tinfo->sock)
1927 				sock_release(tinfo->sock);
1928 			kfree(tinfo->buf);
1929 		}
1930 		kfree(ti);
1931 	}
1932 
1933 	/* decrease the module use count */
1934 	ip_vs_use_count_dec();
1935 	return result;
1936 
1937 out_early:
1938 	mutex_unlock(&ipvs->sync_mutex);
1939 	rtnl_unlock();
1940 
1941 	/* decrease the module use count */
1942 	ip_vs_use_count_dec();
1943 	return result;
1944 }
1945 
1946 
stop_sync_thread(struct netns_ipvs * ipvs,int state)1947 int stop_sync_thread(struct netns_ipvs *ipvs, int state)
1948 {
1949 	struct ip_vs_sync_thread_data *ti, *tinfo;
1950 	int id;
1951 	int retc = -EINVAL;
1952 
1953 	IP_VS_DBG(7, "%s(): pid %d\n", __func__, task_pid_nr(current));
1954 
1955 	mutex_lock(&ipvs->sync_mutex);
1956 	if (state == IP_VS_STATE_MASTER) {
1957 		retc = -ESRCH;
1958 		if (!ipvs->ms)
1959 			goto err;
1960 		ti = ipvs->master_tinfo;
1961 
1962 		/*
1963 		 * The lock synchronizes with sb_queue_tail(), so that we don't
1964 		 * add sync buffers to the queue, when we are already in
1965 		 * progress of stopping the master sync daemon.
1966 		 */
1967 
1968 		spin_lock_bh(&ipvs->sync_buff_lock);
1969 		spin_lock(&ipvs->sync_lock);
1970 		ipvs->sync_state &= ~IP_VS_STATE_MASTER;
1971 		spin_unlock(&ipvs->sync_lock);
1972 		spin_unlock_bh(&ipvs->sync_buff_lock);
1973 
1974 		retc = 0;
1975 		for (id = ipvs->threads_mask; id >= 0; id--) {
1976 			struct ipvs_master_sync_state *ms = &ipvs->ms[id];
1977 			int ret;
1978 
1979 			tinfo = &ti[id];
1980 			pr_info("stopping master sync thread %d ...\n",
1981 				task_pid_nr(tinfo->task));
1982 			cancel_delayed_work_sync(&ms->master_wakeup_work);
1983 			ret = kthread_stop(tinfo->task);
1984 			if (retc >= 0)
1985 				retc = ret;
1986 		}
1987 		kfree(ipvs->ms);
1988 		ipvs->ms = NULL;
1989 		ipvs->master_tinfo = NULL;
1990 	} else if (state == IP_VS_STATE_BACKUP) {
1991 		retc = -ESRCH;
1992 		if (!ipvs->backup_tinfo)
1993 			goto err;
1994 		ti = ipvs->backup_tinfo;
1995 
1996 		ipvs->sync_state &= ~IP_VS_STATE_BACKUP;
1997 		retc = 0;
1998 		for (id = ipvs->threads_mask; id >= 0; id--) {
1999 			int ret;
2000 
2001 			tinfo = &ti[id];
2002 			pr_info("stopping backup sync thread %d ...\n",
2003 				task_pid_nr(tinfo->task));
2004 			ret = kthread_stop(tinfo->task);
2005 			if (retc >= 0)
2006 				retc = ret;
2007 		}
2008 		ipvs->backup_tinfo = NULL;
2009 	} else {
2010 		goto err;
2011 	}
2012 	id = ipvs->threads_mask;
2013 	mutex_unlock(&ipvs->sync_mutex);
2014 
2015 	/* No more mutexes, release socks */
2016 	for (tinfo = ti + id; tinfo >= ti; tinfo--) {
2017 		if (tinfo->sock)
2018 			sock_release(tinfo->sock);
2019 		kfree(tinfo->buf);
2020 	}
2021 	kfree(ti);
2022 
2023 	/* decrease the module use count */
2024 	ip_vs_use_count_dec();
2025 	return retc;
2026 
2027 err:
2028 	mutex_unlock(&ipvs->sync_mutex);
2029 	return retc;
2030 }
2031 
2032 /*
2033  * Initialize data struct for each netns
2034  */
ip_vs_sync_net_init(struct netns_ipvs * ipvs)2035 int __net_init ip_vs_sync_net_init(struct netns_ipvs *ipvs)
2036 {
2037 	__mutex_init(&ipvs->sync_mutex, "ipvs->sync_mutex", &__ipvs_sync_key);
2038 	spin_lock_init(&ipvs->sync_lock);
2039 	spin_lock_init(&ipvs->sync_buff_lock);
2040 	return 0;
2041 }
2042 
ip_vs_sync_net_cleanup(struct netns_ipvs * ipvs)2043 void ip_vs_sync_net_cleanup(struct netns_ipvs *ipvs)
2044 {
2045 	int retc;
2046 
2047 	retc = stop_sync_thread(ipvs, IP_VS_STATE_MASTER);
2048 	if (retc && retc != -ESRCH)
2049 		pr_err("Failed to stop Master Daemon\n");
2050 
2051 	retc = stop_sync_thread(ipvs, IP_VS_STATE_BACKUP);
2052 	if (retc && retc != -ESRCH)
2053 		pr_err("Failed to stop Backup Daemon\n");
2054 }
2055