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