blob: 2cf47b2e1669c8ad39b490586d6088b2a7cc8572 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
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 *
Linus Torvalds1da177e2005-04-16 15:20:36 -07008 * Authors: Wensong Zhang <wensong@linuxvirtualserver.org>
9 *
10 * ip_vs_sync: sync connection info from master load balancer to backups
11 * through multicast
12 *
13 * Changes:
14 * Alexandre Cassen : Added master & backup support at a time.
15 * Alexandre Cassen : Added SyncID support for incoming sync
16 * messages filtering.
17 * Justin Ossevoort : Fix endian problem on sync message size.
18 */
19
20#include <linux/module.h>
21#include <linux/slab.h>
Arnaldo Carvalho de Melo14c85022005-12-27 02:43:12 -020022#include <linux/inetdevice.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070023#include <linux/net.h>
24#include <linux/completion.h>
25#include <linux/delay.h>
26#include <linux/skbuff.h>
27#include <linux/in.h>
28#include <linux/igmp.h> /* for ip_mc_join_group */
Arnaldo Carvalho de Melo14c85022005-12-27 02:43:12 -020029#include <linux/udp.h>
Sven Wegenere6dd7312008-07-16 11:13:43 +000030#include <linux/err.h>
Sven Wegener998e7a72008-07-16 11:13:50 +000031#include <linux/kthread.h>
Sven Wegenerba6fd852008-07-16 11:13:56 +000032#include <linux/wait.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070033
34#include <net/ip.h>
35#include <net/sock.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070036
37#include <net/ip_vs.h>
38
39#define IP_VS_SYNC_GROUP 0xe0000051 /* multicast addr - 224.0.0.81 */
40#define IP_VS_SYNC_PORT 8848 /* multicast port */
41
42
43/*
44 * IPVS sync connection entry
45 */
46struct ip_vs_sync_conn {
47 __u8 reserved;
48
49 /* Protocol, addresses and port numbers */
50 __u8 protocol; /* Which protocol (TCP/UDP) */
Al Viro014d7302006-09-28 14:29:52 -070051 __be16 cport;
52 __be16 vport;
53 __be16 dport;
54 __be32 caddr; /* client address */
55 __be32 vaddr; /* virtual address */
56 __be32 daddr; /* destination address */
Linus Torvalds1da177e2005-04-16 15:20:36 -070057
58 /* Flags and state transition */
Al Viro014d7302006-09-28 14:29:52 -070059 __be16 flags; /* status flags */
60 __be16 state; /* state info */
Linus Torvalds1da177e2005-04-16 15:20:36 -070061
62 /* The sequence options start here */
63};
64
65struct ip_vs_sync_conn_options {
66 struct ip_vs_seq in_seq; /* incoming seq. struct */
67 struct ip_vs_seq out_seq; /* outgoing seq. struct */
68};
69
Neil Hormancc0191a2007-06-18 22:33:20 -070070struct ip_vs_sync_thread_data {
Sven Wegener998e7a72008-07-16 11:13:50 +000071 struct socket *sock;
72 char *buf;
Neil Hormancc0191a2007-06-18 22:33:20 -070073};
74
Linus Torvalds1da177e2005-04-16 15:20:36 -070075#define SIMPLE_CONN_SIZE (sizeof(struct ip_vs_sync_conn))
76#define FULL_CONN_SIZE \
77(sizeof(struct ip_vs_sync_conn) + sizeof(struct ip_vs_sync_conn_options))
78
79
80/*
81 The master mulitcasts messages to the backup load balancers in the
82 following format.
83
84 0 1 2 3
85 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
86 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
87 | Count Conns | SyncID | Size |
88 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
89 | |
90 | IPVS Sync Connection (1) |
91 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
92 | . |
93 | . |
94 | . |
95 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
96 | |
97 | IPVS Sync Connection (n) |
98 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
99*/
100
101#define SYNC_MESG_HEADER_LEN 4
102
103struct ip_vs_sync_mesg {
104 __u8 nr_conns;
105 __u8 syncid;
106 __u16 size;
107
108 /* ip_vs_sync_conn entries start here */
109};
110
111/* the maximum length of sync (sending/receiving) message */
112static int sync_send_mesg_maxlen;
113static int sync_recv_mesg_maxlen;
114
115struct ip_vs_sync_buff {
116 struct list_head list;
117 unsigned long firstuse;
118
119 /* pointers for the message data */
120 struct ip_vs_sync_mesg *mesg;
121 unsigned char *head;
122 unsigned char *end;
123};
124
125
126/* the sync_buff list head and the lock */
127static LIST_HEAD(ip_vs_sync_queue);
128static DEFINE_SPINLOCK(ip_vs_sync_lock);
129
130/* current sync_buff for accepting new conn entries */
131static struct ip_vs_sync_buff *curr_sb = NULL;
132static DEFINE_SPINLOCK(curr_sb_lock);
133
134/* ipvs sync daemon state */
135volatile int ip_vs_sync_state = IP_VS_STATE_NONE;
136volatile int ip_vs_master_syncid = 0;
137volatile int ip_vs_backup_syncid = 0;
138
139/* multicast interface name */
140char ip_vs_master_mcast_ifn[IP_VS_IFNAME_MAXLEN];
141char ip_vs_backup_mcast_ifn[IP_VS_IFNAME_MAXLEN];
142
Sven Wegener998e7a72008-07-16 11:13:50 +0000143/* sync daemon tasks */
144static struct task_struct *sync_master_thread;
145static struct task_struct *sync_backup_thread;
146
Linus Torvalds1da177e2005-04-16 15:20:36 -0700147/* multicast addr */
Sven Wegenerd5640052008-07-16 11:13:35 +0000148static struct sockaddr_in mcast_addr = {
149 .sin_family = AF_INET,
150 .sin_port = __constant_htons(IP_VS_SYNC_PORT),
151 .sin_addr.s_addr = __constant_htonl(IP_VS_SYNC_GROUP),
152};
Linus Torvalds1da177e2005-04-16 15:20:36 -0700153
154
Sven Wegener998e7a72008-07-16 11:13:50 +0000155static inline struct ip_vs_sync_buff *sb_dequeue(void)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700156{
157 struct ip_vs_sync_buff *sb;
158
159 spin_lock_bh(&ip_vs_sync_lock);
160 if (list_empty(&ip_vs_sync_queue)) {
161 sb = NULL;
162 } else {
163 sb = list_entry(ip_vs_sync_queue.next,
164 struct ip_vs_sync_buff,
165 list);
166 list_del(&sb->list);
167 }
168 spin_unlock_bh(&ip_vs_sync_lock);
169
170 return sb;
171}
172
173static inline struct ip_vs_sync_buff * ip_vs_sync_buff_create(void)
174{
175 struct ip_vs_sync_buff *sb;
176
177 if (!(sb=kmalloc(sizeof(struct ip_vs_sync_buff), GFP_ATOMIC)))
178 return NULL;
179
180 if (!(sb->mesg=kmalloc(sync_send_mesg_maxlen, GFP_ATOMIC))) {
181 kfree(sb);
182 return NULL;
183 }
184 sb->mesg->nr_conns = 0;
185 sb->mesg->syncid = ip_vs_master_syncid;
186 sb->mesg->size = 4;
187 sb->head = (unsigned char *)sb->mesg + 4;
188 sb->end = (unsigned char *)sb->mesg + sync_send_mesg_maxlen;
189 sb->firstuse = jiffies;
190 return sb;
191}
192
193static inline void ip_vs_sync_buff_release(struct ip_vs_sync_buff *sb)
194{
195 kfree(sb->mesg);
196 kfree(sb);
197}
198
Sven Wegener998e7a72008-07-16 11:13:50 +0000199static inline void sb_queue_tail(struct ip_vs_sync_buff *sb)
200{
201 spin_lock(&ip_vs_sync_lock);
202 if (ip_vs_sync_state & IP_VS_STATE_MASTER)
203 list_add_tail(&sb->list, &ip_vs_sync_queue);
204 else
205 ip_vs_sync_buff_release(sb);
206 spin_unlock(&ip_vs_sync_lock);
207}
208
Linus Torvalds1da177e2005-04-16 15:20:36 -0700209/*
210 * Get the current sync buffer if it has been created for more
211 * than the specified time or the specified time is zero.
212 */
213static inline struct ip_vs_sync_buff *
214get_curr_sync_buff(unsigned long time)
215{
216 struct ip_vs_sync_buff *sb;
217
218 spin_lock_bh(&curr_sb_lock);
219 if (curr_sb && (time == 0 ||
220 time_before(jiffies - curr_sb->firstuse, time))) {
221 sb = curr_sb;
222 curr_sb = NULL;
223 } else
224 sb = NULL;
225 spin_unlock_bh(&curr_sb_lock);
226 return sb;
227}
228
229
230/*
231 * Add an ip_vs_conn information into the current sync_buff.
232 * Called by ip_vs_in.
233 */
234void ip_vs_sync_conn(struct ip_vs_conn *cp)
235{
236 struct ip_vs_sync_mesg *m;
237 struct ip_vs_sync_conn *s;
238 int len;
239
240 spin_lock(&curr_sb_lock);
241 if (!curr_sb) {
242 if (!(curr_sb=ip_vs_sync_buff_create())) {
243 spin_unlock(&curr_sb_lock);
244 IP_VS_ERR("ip_vs_sync_buff_create failed.\n");
245 return;
246 }
247 }
248
249 len = (cp->flags & IP_VS_CONN_F_SEQ_MASK) ? FULL_CONN_SIZE :
250 SIMPLE_CONN_SIZE;
251 m = curr_sb->mesg;
252 s = (struct ip_vs_sync_conn *)curr_sb->head;
253
254 /* copy members */
255 s->protocol = cp->protocol;
256 s->cport = cp->cport;
257 s->vport = cp->vport;
258 s->dport = cp->dport;
Julius Volze7ade462008-09-02 15:55:33 +0200259 s->caddr = cp->caddr.ip;
260 s->vaddr = cp->vaddr.ip;
261 s->daddr = cp->daddr.ip;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700262 s->flags = htons(cp->flags & ~IP_VS_CONN_F_HASHED);
263 s->state = htons(cp->state);
264 if (cp->flags & IP_VS_CONN_F_SEQ_MASK) {
265 struct ip_vs_sync_conn_options *opt =
266 (struct ip_vs_sync_conn_options *)&s[1];
267 memcpy(opt, &cp->in_seq, sizeof(*opt));
268 }
269
270 m->nr_conns++;
271 m->size += len;
272 curr_sb->head += len;
273
274 /* check if there is a space for next one */
275 if (curr_sb->head+FULL_CONN_SIZE > curr_sb->end) {
276 sb_queue_tail(curr_sb);
277 curr_sb = NULL;
278 }
279 spin_unlock(&curr_sb_lock);
280
281 /* synchronize its controller if it has */
282 if (cp->control)
283 ip_vs_sync_conn(cp->control);
284}
285
286
287/*
288 * Process received multicast message and create the corresponding
289 * ip_vs_conn entries.
290 */
291static void ip_vs_process_message(const char *buffer, const size_t buflen)
292{
293 struct ip_vs_sync_mesg *m = (struct ip_vs_sync_mesg *)buffer;
294 struct ip_vs_sync_conn *s;
295 struct ip_vs_sync_conn_options *opt;
296 struct ip_vs_conn *cp;
Andy Gospodarek5c818332007-10-29 04:35:45 -0700297 struct ip_vs_protocol *pp;
Rumen G. Bogdanovski1e356f92007-11-07 02:35:54 -0800298 struct ip_vs_dest *dest;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700299 char *p;
300 int i;
301
Julian Anastasov2ad17de2008-04-29 03:21:23 -0700302 if (buflen < sizeof(struct ip_vs_sync_mesg)) {
303 IP_VS_ERR_RL("sync message header too short\n");
304 return;
305 }
306
Linus Torvalds1da177e2005-04-16 15:20:36 -0700307 /* Convert size back to host byte order */
308 m->size = ntohs(m->size);
309
310 if (buflen != m->size) {
Julian Anastasov2ad17de2008-04-29 03:21:23 -0700311 IP_VS_ERR_RL("bogus sync message size\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700312 return;
313 }
314
315 /* SyncID sanity check */
316 if (ip_vs_backup_syncid != 0 && m->syncid != ip_vs_backup_syncid) {
317 IP_VS_DBG(7, "Ignoring incoming msg with syncid = %d\n",
318 m->syncid);
319 return;
320 }
321
322 p = (char *)buffer + sizeof(struct ip_vs_sync_mesg);
323 for (i=0; i<m->nr_conns; i++) {
Rumen G. Bogdanovskib2096392007-11-19 21:53:27 -0800324 unsigned flags, state;
Julian Anastasov87375ab2005-09-14 21:08:51 -0700325
Julian Anastasov2ad17de2008-04-29 03:21:23 -0700326 if (p + SIMPLE_CONN_SIZE > buffer+buflen) {
327 IP_VS_ERR_RL("bogus conn in sync message\n");
328 return;
329 }
330 s = (struct ip_vs_sync_conn *) p;
Rumen G. Bogdanovski7a4fbb12007-11-19 21:52:42 -0800331 flags = ntohs(s->flags) | IP_VS_CONN_F_SYNC;
Julian Anastasov2ad17de2008-04-29 03:21:23 -0700332 flags &= ~IP_VS_CONN_F_HASHED;
333 if (flags & IP_VS_CONN_F_SEQ_MASK) {
334 opt = (struct ip_vs_sync_conn_options *)&s[1];
335 p += FULL_CONN_SIZE;
336 if (p > buffer+buflen) {
337 IP_VS_ERR_RL("bogus conn options in sync message\n");
338 return;
339 }
340 } else {
341 opt = NULL;
342 p += SIMPLE_CONN_SIZE;
343 }
344
Rumen G. Bogdanovskib2096392007-11-19 21:53:27 -0800345 state = ntohs(s->state);
Julian Anastasov2ad17de2008-04-29 03:21:23 -0700346 if (!(flags & IP_VS_CONN_F_TEMPLATE)) {
347 pp = ip_vs_proto_get(s->protocol);
348 if (!pp) {
349 IP_VS_ERR_RL("Unsupported protocol %u in sync msg\n",
350 s->protocol);
351 continue;
352 }
353 if (state >= pp->num_states) {
354 IP_VS_DBG(2, "Invalid %s state %u in sync msg\n",
355 pp->name, state);
356 continue;
357 }
358 } else {
359 /* protocol in templates is not used for state/timeout */
360 pp = NULL;
361 if (state > 0) {
362 IP_VS_DBG(2, "Invalid template state %u in sync msg\n",
363 state);
364 state = 0;
365 }
366 }
367
Julian Anastasov87375ab2005-09-14 21:08:51 -0700368 if (!(flags & IP_VS_CONN_F_TEMPLATE))
369 cp = ip_vs_conn_in_get(s->protocol,
370 s->caddr, s->cport,
371 s->vaddr, s->vport);
372 else
373 cp = ip_vs_ct_in_get(s->protocol,
374 s->caddr, s->cport,
375 s->vaddr, s->vport);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700376 if (!cp) {
Rumen G. Bogdanovski1e356f92007-11-07 02:35:54 -0800377 /*
378 * Find the appropriate destination for the connection.
379 * If it is not found the connection will remain unbound
380 * but still handled.
381 */
382 dest = ip_vs_find_dest(s->daddr, s->dport,
383 s->vaddr, s->vport,
384 s->protocol);
Rumen G. Bogdanovskib2096392007-11-19 21:53:27 -0800385 /* Set the approprite ativity flag */
386 if (s->protocol == IPPROTO_TCP) {
387 if (state != IP_VS_TCP_S_ESTABLISHED)
388 flags |= IP_VS_CONN_F_INACTIVE;
389 else
390 flags &= ~IP_VS_CONN_F_INACTIVE;
391 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700392 cp = ip_vs_conn_new(s->protocol,
393 s->caddr, s->cport,
394 s->vaddr, s->vport,
395 s->daddr, s->dport,
Rumen G. Bogdanovski1e356f92007-11-07 02:35:54 -0800396 flags, dest);
397 if (dest)
398 atomic_dec(&dest->refcnt);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700399 if (!cp) {
400 IP_VS_ERR("ip_vs_conn_new failed\n");
401 return;
402 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700403 } else if (!cp->dest) {
Rumen G. Bogdanovski1e356f92007-11-07 02:35:54 -0800404 dest = ip_vs_try_bind_dest(cp);
Julian Anastasov2ad17de2008-04-29 03:21:23 -0700405 if (dest)
Rumen G. Bogdanovski1e356f92007-11-07 02:35:54 -0800406 atomic_dec(&dest->refcnt);
Rumen G. Bogdanovskib2096392007-11-19 21:53:27 -0800407 } else if ((cp->dest) && (cp->protocol == IPPROTO_TCP) &&
408 (cp->state != state)) {
409 /* update active/inactive flag for the connection */
410 dest = cp->dest;
411 if (!(cp->flags & IP_VS_CONN_F_INACTIVE) &&
412 (state != IP_VS_TCP_S_ESTABLISHED)) {
413 atomic_dec(&dest->activeconns);
414 atomic_inc(&dest->inactconns);
415 cp->flags |= IP_VS_CONN_F_INACTIVE;
416 } else if ((cp->flags & IP_VS_CONN_F_INACTIVE) &&
417 (state == IP_VS_TCP_S_ESTABLISHED)) {
418 atomic_inc(&dest->activeconns);
419 atomic_dec(&dest->inactconns);
420 cp->flags &= ~IP_VS_CONN_F_INACTIVE;
421 }
422 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700423
Julian Anastasov2ad17de2008-04-29 03:21:23 -0700424 if (opt)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700425 memcpy(&cp->in_seq, opt, sizeof(*opt));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700426 atomic_set(&cp->in_pkts, sysctl_ip_vs_sync_threshold[0]);
Rumen G. Bogdanovskib2096392007-11-19 21:53:27 -0800427 cp->state = state;
Julian Anastasov2ad17de2008-04-29 03:21:23 -0700428 cp->old_state = cp->state;
429 /*
430 * We can not recover the right timeout for templates
431 * in all cases, we can not find the right fwmark
432 * virtual service. If needed, we can do it for
433 * non-fwmark persistent services.
434 */
435 if (!(flags & IP_VS_CONN_F_TEMPLATE) && pp->timeout_table)
436 cp->timeout = pp->timeout_table[state];
437 else
438 cp->timeout = (3*60*HZ);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700439 ip_vs_conn_put(cp);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700440 }
441}
442
443
444/*
445 * Setup loopback of outgoing multicasts on a sending socket
446 */
447static void set_mcast_loop(struct sock *sk, u_char loop)
448{
449 struct inet_sock *inet = inet_sk(sk);
450
451 /* setsockopt(sock, SOL_IP, IP_MULTICAST_LOOP, &loop, sizeof(loop)); */
452 lock_sock(sk);
453 inet->mc_loop = loop ? 1 : 0;
454 release_sock(sk);
455}
456
457/*
458 * Specify TTL for outgoing multicasts on a sending socket
459 */
460static void set_mcast_ttl(struct sock *sk, u_char ttl)
461{
462 struct inet_sock *inet = inet_sk(sk);
463
464 /* setsockopt(sock, SOL_IP, IP_MULTICAST_TTL, &ttl, sizeof(ttl)); */
465 lock_sock(sk);
466 inet->mc_ttl = ttl;
467 release_sock(sk);
468}
469
470/*
471 * Specifiy default interface for outgoing multicasts
472 */
473static int set_mcast_if(struct sock *sk, char *ifname)
474{
475 struct net_device *dev;
476 struct inet_sock *inet = inet_sk(sk);
477
Eric W. Biederman881d9662007-09-17 11:56:21 -0700478 if ((dev = __dev_get_by_name(&init_net, ifname)) == NULL)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700479 return -ENODEV;
480
481 if (sk->sk_bound_dev_if && dev->ifindex != sk->sk_bound_dev_if)
482 return -EINVAL;
483
484 lock_sock(sk);
485 inet->mc_index = dev->ifindex;
486 /* inet->mc_addr = 0; */
487 release_sock(sk);
488
489 return 0;
490}
491
492
493/*
494 * Set the maximum length of sync message according to the
495 * specified interface's MTU.
496 */
497static int set_sync_mesg_maxlen(int sync_state)
498{
499 struct net_device *dev;
500 int num;
501
502 if (sync_state == IP_VS_STATE_MASTER) {
Eric W. Biederman881d9662007-09-17 11:56:21 -0700503 if ((dev = __dev_get_by_name(&init_net, ip_vs_master_mcast_ifn)) == NULL)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700504 return -ENODEV;
505
506 num = (dev->mtu - sizeof(struct iphdr) -
507 sizeof(struct udphdr) -
508 SYNC_MESG_HEADER_LEN - 20) / SIMPLE_CONN_SIZE;
509 sync_send_mesg_maxlen =
510 SYNC_MESG_HEADER_LEN + SIMPLE_CONN_SIZE * num;
511 IP_VS_DBG(7, "setting the maximum length of sync sending "
512 "message %d.\n", sync_send_mesg_maxlen);
513 } else if (sync_state == IP_VS_STATE_BACKUP) {
Eric W. Biederman881d9662007-09-17 11:56:21 -0700514 if ((dev = __dev_get_by_name(&init_net, ip_vs_backup_mcast_ifn)) == NULL)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700515 return -ENODEV;
516
517 sync_recv_mesg_maxlen = dev->mtu -
518 sizeof(struct iphdr) - sizeof(struct udphdr);
519 IP_VS_DBG(7, "setting the maximum length of sync receiving "
520 "message %d.\n", sync_recv_mesg_maxlen);
521 }
522
523 return 0;
524}
525
526
527/*
528 * Join a multicast group.
529 * the group is specified by a class D multicast address 224.0.0.0/8
530 * in the in_addr structure passed in as a parameter.
531 */
532static int
533join_mcast_group(struct sock *sk, struct in_addr *addr, char *ifname)
534{
535 struct ip_mreqn mreq;
536 struct net_device *dev;
537 int ret;
538
539 memset(&mreq, 0, sizeof(mreq));
540 memcpy(&mreq.imr_multiaddr, addr, sizeof(struct in_addr));
541
Eric W. Biederman881d9662007-09-17 11:56:21 -0700542 if ((dev = __dev_get_by_name(&init_net, ifname)) == NULL)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700543 return -ENODEV;
544 if (sk->sk_bound_dev_if && dev->ifindex != sk->sk_bound_dev_if)
545 return -EINVAL;
546
547 mreq.imr_ifindex = dev->ifindex;
548
549 lock_sock(sk);
550 ret = ip_mc_join_group(sk, &mreq);
551 release_sock(sk);
552
553 return ret;
554}
555
556
557static int bind_mcastif_addr(struct socket *sock, char *ifname)
558{
559 struct net_device *dev;
Al Viroa61ced52006-09-26 21:27:54 -0700560 __be32 addr;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700561 struct sockaddr_in sin;
562
Eric W. Biederman881d9662007-09-17 11:56:21 -0700563 if ((dev = __dev_get_by_name(&init_net, ifname)) == NULL)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700564 return -ENODEV;
565
566 addr = inet_select_addr(dev, 0, RT_SCOPE_UNIVERSE);
567 if (!addr)
568 IP_VS_ERR("You probably need to specify IP address on "
569 "multicast interface.\n");
570
571 IP_VS_DBG(7, "binding socket with (%s) %u.%u.%u.%u\n",
572 ifname, NIPQUAD(addr));
573
574 /* Now bind the socket with the address of multicast interface */
575 sin.sin_family = AF_INET;
576 sin.sin_addr.s_addr = addr;
577 sin.sin_port = 0;
578
579 return sock->ops->bind(sock, (struct sockaddr*)&sin, sizeof(sin));
580}
581
582/*
583 * Set up sending multicast socket over UDP
584 */
585static struct socket * make_send_sock(void)
586{
587 struct socket *sock;
Sven Wegenere6dd7312008-07-16 11:13:43 +0000588 int result;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700589
590 /* First create a socket */
Sven Wegenere6dd7312008-07-16 11:13:43 +0000591 result = sock_create_kern(PF_INET, SOCK_DGRAM, IPPROTO_UDP, &sock);
592 if (result < 0) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700593 IP_VS_ERR("Error during creation of socket; terminating\n");
Sven Wegenere6dd7312008-07-16 11:13:43 +0000594 return ERR_PTR(result);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700595 }
596
Sven Wegenere6dd7312008-07-16 11:13:43 +0000597 result = set_mcast_if(sock->sk, ip_vs_master_mcast_ifn);
598 if (result < 0) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700599 IP_VS_ERR("Error setting outbound mcast interface\n");
600 goto error;
601 }
602
603 set_mcast_loop(sock->sk, 0);
604 set_mcast_ttl(sock->sk, 1);
605
Sven Wegenere6dd7312008-07-16 11:13:43 +0000606 result = bind_mcastif_addr(sock, ip_vs_master_mcast_ifn);
607 if (result < 0) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700608 IP_VS_ERR("Error binding address of the mcast interface\n");
609 goto error;
610 }
611
Sven Wegenere6dd7312008-07-16 11:13:43 +0000612 result = sock->ops->connect(sock, (struct sockaddr *) &mcast_addr,
613 sizeof(struct sockaddr), 0);
614 if (result < 0) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700615 IP_VS_ERR("Error connecting to the multicast addr\n");
616 goto error;
617 }
618
619 return sock;
620
621 error:
622 sock_release(sock);
Sven Wegenere6dd7312008-07-16 11:13:43 +0000623 return ERR_PTR(result);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700624}
625
626
627/*
628 * Set up receiving multicast socket over UDP
629 */
630static struct socket * make_receive_sock(void)
631{
632 struct socket *sock;
Sven Wegenere6dd7312008-07-16 11:13:43 +0000633 int result;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700634
635 /* First create a socket */
Sven Wegenere6dd7312008-07-16 11:13:43 +0000636 result = sock_create_kern(PF_INET, SOCK_DGRAM, IPPROTO_UDP, &sock);
637 if (result < 0) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700638 IP_VS_ERR("Error during creation of socket; terminating\n");
Sven Wegenere6dd7312008-07-16 11:13:43 +0000639 return ERR_PTR(result);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700640 }
641
642 /* it is equivalent to the REUSEADDR option in user-space */
643 sock->sk->sk_reuse = 1;
644
Sven Wegenere6dd7312008-07-16 11:13:43 +0000645 result = sock->ops->bind(sock, (struct sockaddr *) &mcast_addr,
646 sizeof(struct sockaddr));
647 if (result < 0) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700648 IP_VS_ERR("Error binding to the multicast addr\n");
649 goto error;
650 }
651
652 /* join the multicast group */
Sven Wegenere6dd7312008-07-16 11:13:43 +0000653 result = join_mcast_group(sock->sk,
654 (struct in_addr *) &mcast_addr.sin_addr,
655 ip_vs_backup_mcast_ifn);
656 if (result < 0) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700657 IP_VS_ERR("Error joining to the multicast group\n");
658 goto error;
659 }
660
661 return sock;
662
663 error:
664 sock_release(sock);
Sven Wegenere6dd7312008-07-16 11:13:43 +0000665 return ERR_PTR(result);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700666}
667
668
669static int
670ip_vs_send_async(struct socket *sock, const char *buffer, const size_t length)
671{
672 struct msghdr msg = {.msg_flags = MSG_DONTWAIT|MSG_NOSIGNAL};
673 struct kvec iov;
674 int len;
675
676 EnterFunction(7);
677 iov.iov_base = (void *)buffer;
678 iov.iov_len = length;
679
680 len = kernel_sendmsg(sock, &msg, &iov, 1, (size_t)(length));
681
682 LeaveFunction(7);
683 return len;
684}
685
686static void
687ip_vs_send_sync_msg(struct socket *sock, struct ip_vs_sync_mesg *msg)
688{
689 int msize;
690
691 msize = msg->size;
692
693 /* Put size in network byte order */
694 msg->size = htons(msg->size);
695
696 if (ip_vs_send_async(sock, (char *)msg, msize) != msize)
697 IP_VS_ERR("ip_vs_send_async error\n");
698}
699
700static int
701ip_vs_receive(struct socket *sock, char *buffer, const size_t buflen)
702{
703 struct msghdr msg = {NULL,};
704 struct kvec iov;
705 int len;
706
707 EnterFunction(7);
708
709 /* Receive a packet */
710 iov.iov_base = buffer;
711 iov.iov_len = (size_t)buflen;
712
713 len = kernel_recvmsg(sock, &msg, &iov, 1, buflen, 0);
714
715 if (len < 0)
716 return -1;
717
718 LeaveFunction(7);
719 return len;
720}
721
722
Sven Wegener998e7a72008-07-16 11:13:50 +0000723static int sync_thread_master(void *data)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700724{
Sven Wegener998e7a72008-07-16 11:13:50 +0000725 struct ip_vs_sync_thread_data *tinfo = data;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700726 struct ip_vs_sync_buff *sb;
727
Linus Torvalds1da177e2005-04-16 15:20:36 -0700728 IP_VS_INFO("sync thread started: state = MASTER, mcast_ifn = %s, "
729 "syncid = %d\n",
730 ip_vs_master_mcast_ifn, ip_vs_master_syncid);
731
Sven Wegener998e7a72008-07-16 11:13:50 +0000732 while (!kthread_should_stop()) {
733 while ((sb = sb_dequeue())) {
734 ip_vs_send_sync_msg(tinfo->sock, sb->mesg);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700735 ip_vs_sync_buff_release(sb);
736 }
737
738 /* check if entries stay in curr_sb for 2 seconds */
Sven Wegener998e7a72008-07-16 11:13:50 +0000739 sb = get_curr_sync_buff(2 * HZ);
740 if (sb) {
741 ip_vs_send_sync_msg(tinfo->sock, sb->mesg);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700742 ip_vs_sync_buff_release(sb);
743 }
744
Sven Wegener375c6bb2008-07-16 11:14:03 +0000745 schedule_timeout_interruptible(HZ);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700746 }
747
748 /* clean up the sync_buff queue */
749 while ((sb=sb_dequeue())) {
750 ip_vs_sync_buff_release(sb);
751 }
752
753 /* clean up the current sync_buff */
754 if ((sb = get_curr_sync_buff(0))) {
755 ip_vs_sync_buff_release(sb);
756 }
757
758 /* release the sending multicast socket */
Sven Wegener998e7a72008-07-16 11:13:50 +0000759 sock_release(tinfo->sock);
760 kfree(tinfo);
761
762 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700763}
764
765
Sven Wegener998e7a72008-07-16 11:13:50 +0000766static int sync_thread_backup(void *data)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700767{
Sven Wegener998e7a72008-07-16 11:13:50 +0000768 struct ip_vs_sync_thread_data *tinfo = data;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700769 int len;
770
Linus Torvalds1da177e2005-04-16 15:20:36 -0700771 IP_VS_INFO("sync thread started: state = BACKUP, mcast_ifn = %s, "
772 "syncid = %d\n",
773 ip_vs_backup_mcast_ifn, ip_vs_backup_syncid);
774
Sven Wegener998e7a72008-07-16 11:13:50 +0000775 while (!kthread_should_stop()) {
Sven Wegenerba6fd852008-07-16 11:13:56 +0000776 wait_event_interruptible(*tinfo->sock->sk->sk_sleep,
777 !skb_queue_empty(&tinfo->sock->sk->sk_receive_queue)
778 || kthread_should_stop());
779
Sven Wegener998e7a72008-07-16 11:13:50 +0000780 /* do we have data now? */
781 while (!skb_queue_empty(&(tinfo->sock->sk->sk_receive_queue))) {
782 len = ip_vs_receive(tinfo->sock, tinfo->buf,
783 sync_recv_mesg_maxlen);
784 if (len <= 0) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700785 IP_VS_ERR("receiving message error\n");
786 break;
787 }
Sven Wegener998e7a72008-07-16 11:13:50 +0000788
789 /* disable bottom half, because it accesses the data
Linus Torvalds1da177e2005-04-16 15:20:36 -0700790 shared by softirq while getting/creating conns */
791 local_bh_disable();
Sven Wegener998e7a72008-07-16 11:13:50 +0000792 ip_vs_process_message(tinfo->buf, len);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700793 local_bh_enable();
794 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700795 }
796
797 /* release the sending multicast socket */
Sven Wegener998e7a72008-07-16 11:13:50 +0000798 sock_release(tinfo->sock);
799 kfree(tinfo->buf);
Neil Hormancc0191a2007-06-18 22:33:20 -0700800 kfree(tinfo);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700801
802 return 0;
803}
804
805
806int start_sync_thread(int state, char *mcast_ifn, __u8 syncid)
807{
Neil Hormancc0191a2007-06-18 22:33:20 -0700808 struct ip_vs_sync_thread_data *tinfo;
Sven Wegener998e7a72008-07-16 11:13:50 +0000809 struct task_struct **realtask, *task;
810 struct socket *sock;
811 char *name, *buf = NULL;
812 int (*threadfn)(void *data);
813 int result = -ENOMEM;
Neil Hormancc0191a2007-06-18 22:33:20 -0700814
Harvey Harrison0dc47872008-03-05 20:47:47 -0800815 IP_VS_DBG(7, "%s: pid %d\n", __func__, task_pid_nr(current));
Sven Wegener998e7a72008-07-16 11:13:50 +0000816 IP_VS_DBG(7, "Each ip_vs_sync_conn entry needs %Zd bytes\n",
Linus Torvalds1da177e2005-04-16 15:20:36 -0700817 sizeof(struct ip_vs_sync_conn));
818
Linus Torvalds1da177e2005-04-16 15:20:36 -0700819 if (state == IP_VS_STATE_MASTER) {
Sven Wegener998e7a72008-07-16 11:13:50 +0000820 if (sync_master_thread)
821 return -EEXIST;
822
Simon Horman37004af2006-12-10 22:36:18 -0800823 strlcpy(ip_vs_master_mcast_ifn, mcast_ifn,
824 sizeof(ip_vs_master_mcast_ifn));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700825 ip_vs_master_syncid = syncid;
Sven Wegener998e7a72008-07-16 11:13:50 +0000826 realtask = &sync_master_thread;
827 name = "ipvs_syncmaster";
828 threadfn = sync_thread_master;
829 sock = make_send_sock();
830 } else if (state == IP_VS_STATE_BACKUP) {
831 if (sync_backup_thread)
832 return -EEXIST;
833
Simon Horman37004af2006-12-10 22:36:18 -0800834 strlcpy(ip_vs_backup_mcast_ifn, mcast_ifn,
835 sizeof(ip_vs_backup_mcast_ifn));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700836 ip_vs_backup_syncid = syncid;
Sven Wegener998e7a72008-07-16 11:13:50 +0000837 realtask = &sync_backup_thread;
838 name = "ipvs_syncbackup";
839 threadfn = sync_thread_backup;
840 sock = make_receive_sock();
841 } else {
842 return -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700843 }
844
Sven Wegener998e7a72008-07-16 11:13:50 +0000845 if (IS_ERR(sock)) {
846 result = PTR_ERR(sock);
847 goto out;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700848 }
849
Sven Wegener998e7a72008-07-16 11:13:50 +0000850 set_sync_mesg_maxlen(state);
851 if (state == IP_VS_STATE_BACKUP) {
852 buf = kmalloc(sync_recv_mesg_maxlen, GFP_KERNEL);
853 if (!buf)
854 goto outsocket;
855 }
856
857 tinfo = kmalloc(sizeof(*tinfo), GFP_KERNEL);
858 if (!tinfo)
859 goto outbuf;
860
861 tinfo->sock = sock;
862 tinfo->buf = buf;
863
864 task = kthread_run(threadfn, tinfo, name);
865 if (IS_ERR(task)) {
866 result = PTR_ERR(task);
867 goto outtinfo;
868 }
869
870 /* mark as active */
871 *realtask = task;
872 ip_vs_sync_state |= state;
873
874 /* increase the module use count */
875 ip_vs_use_count_inc();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700876
877 return 0;
Sven Wegener998e7a72008-07-16 11:13:50 +0000878
879outtinfo:
880 kfree(tinfo);
881outbuf:
882 kfree(buf);
883outsocket:
884 sock_release(sock);
885out:
886 return result;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700887}
888
889
890int stop_sync_thread(int state)
891{
Harvey Harrison0dc47872008-03-05 20:47:47 -0800892 IP_VS_DBG(7, "%s: pid %d\n", __func__, task_pid_nr(current));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700893
Sven Wegener998e7a72008-07-16 11:13:50 +0000894 if (state == IP_VS_STATE_MASTER) {
895 if (!sync_master_thread)
896 return -ESRCH;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700897
Sven Wegener998e7a72008-07-16 11:13:50 +0000898 IP_VS_INFO("stopping master sync thread %d ...\n",
899 task_pid_nr(sync_master_thread));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700900
Sven Wegener998e7a72008-07-16 11:13:50 +0000901 /*
902 * The lock synchronizes with sb_queue_tail(), so that we don't
903 * add sync buffers to the queue, when we are already in
904 * progress of stopping the master sync daemon.
905 */
906
Sven Wegenerbc0fde22008-08-10 09:14:05 +0000907 spin_lock_bh(&ip_vs_sync_lock);
Sven Wegener998e7a72008-07-16 11:13:50 +0000908 ip_vs_sync_state &= ~IP_VS_STATE_MASTER;
Sven Wegenerbc0fde22008-08-10 09:14:05 +0000909 spin_unlock_bh(&ip_vs_sync_lock);
Sven Wegener998e7a72008-07-16 11:13:50 +0000910 kthread_stop(sync_master_thread);
911 sync_master_thread = NULL;
912 } else if (state == IP_VS_STATE_BACKUP) {
913 if (!sync_backup_thread)
914 return -ESRCH;
915
916 IP_VS_INFO("stopping backup sync thread %d ...\n",
917 task_pid_nr(sync_backup_thread));
918
919 ip_vs_sync_state &= ~IP_VS_STATE_BACKUP;
920 kthread_stop(sync_backup_thread);
921 sync_backup_thread = NULL;
922 } else {
923 return -EINVAL;
924 }
925
926 /* decrease the module use count */
927 ip_vs_use_count_dec();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700928
929 return 0;
930}