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1da177e4 LT |
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 | * | |
1da177e4 LT |
8 | * 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> | |
14c85021 | 22 | #include <linux/inetdevice.h> |
1da177e4 LT |
23 | #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 */ | |
14c85021 | 29 | #include <linux/udp.h> |
1da177e4 LT |
30 | |
31 | #include <net/ip.h> | |
32 | #include <net/sock.h> | |
33 | #include <asm/uaccess.h> /* for get_fs and set_fs */ | |
34 | ||
35 | #include <net/ip_vs.h> | |
36 | ||
37 | #define IP_VS_SYNC_GROUP 0xe0000051 /* multicast addr - 224.0.0.81 */ | |
38 | #define IP_VS_SYNC_PORT 8848 /* multicast port */ | |
39 | ||
40 | ||
41 | /* | |
42 | * IPVS sync connection entry | |
43 | */ | |
44 | struct ip_vs_sync_conn { | |
45 | __u8 reserved; | |
46 | ||
47 | /* Protocol, addresses and port numbers */ | |
48 | __u8 protocol; /* Which protocol (TCP/UDP) */ | |
014d730d AV |
49 | __be16 cport; |
50 | __be16 vport; | |
51 | __be16 dport; | |
52 | __be32 caddr; /* client address */ | |
53 | __be32 vaddr; /* virtual address */ | |
54 | __be32 daddr; /* destination address */ | |
1da177e4 LT |
55 | |
56 | /* Flags and state transition */ | |
014d730d AV |
57 | __be16 flags; /* status flags */ |
58 | __be16 state; /* state info */ | |
1da177e4 LT |
59 | |
60 | /* The sequence options start here */ | |
61 | }; | |
62 | ||
63 | struct ip_vs_sync_conn_options { | |
64 | struct ip_vs_seq in_seq; /* incoming seq. struct */ | |
65 | struct ip_vs_seq out_seq; /* outgoing seq. struct */ | |
66 | }; | |
67 | ||
cc0191ae NH |
68 | struct ip_vs_sync_thread_data { |
69 | struct completion *startup; | |
70 | int state; | |
71 | }; | |
72 | ||
1da177e4 LT |
73 | #define SIMPLE_CONN_SIZE (sizeof(struct ip_vs_sync_conn)) |
74 | #define FULL_CONN_SIZE \ | |
75 | (sizeof(struct ip_vs_sync_conn) + sizeof(struct ip_vs_sync_conn_options)) | |
76 | ||
77 | ||
78 | /* | |
79 | The master mulitcasts messages to the backup load balancers in the | |
80 | following format. | |
81 | ||
82 | 0 1 2 3 | |
83 | 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 | |
84 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
85 | | Count Conns | SyncID | Size | | |
86 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
87 | | | | |
88 | | IPVS Sync Connection (1) | | |
89 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
90 | | . | | |
91 | | . | | |
92 | | . | | |
93 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
94 | | | | |
95 | | IPVS Sync Connection (n) | | |
96 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
97 | */ | |
98 | ||
99 | #define SYNC_MESG_HEADER_LEN 4 | |
100 | ||
101 | struct ip_vs_sync_mesg { | |
102 | __u8 nr_conns; | |
103 | __u8 syncid; | |
104 | __u16 size; | |
105 | ||
106 | /* ip_vs_sync_conn entries start here */ | |
107 | }; | |
108 | ||
109 | /* the maximum length of sync (sending/receiving) message */ | |
110 | static int sync_send_mesg_maxlen; | |
111 | static int sync_recv_mesg_maxlen; | |
112 | ||
113 | struct ip_vs_sync_buff { | |
114 | struct list_head list; | |
115 | unsigned long firstuse; | |
116 | ||
117 | /* pointers for the message data */ | |
118 | struct ip_vs_sync_mesg *mesg; | |
119 | unsigned char *head; | |
120 | unsigned char *end; | |
121 | }; | |
122 | ||
123 | ||
124 | /* the sync_buff list head and the lock */ | |
125 | static LIST_HEAD(ip_vs_sync_queue); | |
126 | static DEFINE_SPINLOCK(ip_vs_sync_lock); | |
127 | ||
128 | /* current sync_buff for accepting new conn entries */ | |
129 | static struct ip_vs_sync_buff *curr_sb = NULL; | |
130 | static DEFINE_SPINLOCK(curr_sb_lock); | |
131 | ||
132 | /* ipvs sync daemon state */ | |
133 | volatile int ip_vs_sync_state = IP_VS_STATE_NONE; | |
134 | volatile int ip_vs_master_syncid = 0; | |
135 | volatile int ip_vs_backup_syncid = 0; | |
136 | ||
137 | /* multicast interface name */ | |
138 | char ip_vs_master_mcast_ifn[IP_VS_IFNAME_MAXLEN]; | |
139 | char ip_vs_backup_mcast_ifn[IP_VS_IFNAME_MAXLEN]; | |
140 | ||
141 | /* multicast addr */ | |
142 | static struct sockaddr_in mcast_addr; | |
143 | ||
144 | ||
145 | static inline void sb_queue_tail(struct ip_vs_sync_buff *sb) | |
146 | { | |
147 | spin_lock(&ip_vs_sync_lock); | |
148 | list_add_tail(&sb->list, &ip_vs_sync_queue); | |
149 | spin_unlock(&ip_vs_sync_lock); | |
150 | } | |
151 | ||
152 | static inline struct ip_vs_sync_buff * sb_dequeue(void) | |
153 | { | |
154 | struct ip_vs_sync_buff *sb; | |
155 | ||
156 | spin_lock_bh(&ip_vs_sync_lock); | |
157 | if (list_empty(&ip_vs_sync_queue)) { | |
158 | sb = NULL; | |
159 | } else { | |
160 | sb = list_entry(ip_vs_sync_queue.next, | |
161 | struct ip_vs_sync_buff, | |
162 | list); | |
163 | list_del(&sb->list); | |
164 | } | |
165 | spin_unlock_bh(&ip_vs_sync_lock); | |
166 | ||
167 | return sb; | |
168 | } | |
169 | ||
170 | static inline struct ip_vs_sync_buff * ip_vs_sync_buff_create(void) | |
171 | { | |
172 | struct ip_vs_sync_buff *sb; | |
173 | ||
174 | if (!(sb=kmalloc(sizeof(struct ip_vs_sync_buff), GFP_ATOMIC))) | |
175 | return NULL; | |
176 | ||
177 | if (!(sb->mesg=kmalloc(sync_send_mesg_maxlen, GFP_ATOMIC))) { | |
178 | kfree(sb); | |
179 | return NULL; | |
180 | } | |
181 | sb->mesg->nr_conns = 0; | |
182 | sb->mesg->syncid = ip_vs_master_syncid; | |
183 | sb->mesg->size = 4; | |
184 | sb->head = (unsigned char *)sb->mesg + 4; | |
185 | sb->end = (unsigned char *)sb->mesg + sync_send_mesg_maxlen; | |
186 | sb->firstuse = jiffies; | |
187 | return sb; | |
188 | } | |
189 | ||
190 | static inline void ip_vs_sync_buff_release(struct ip_vs_sync_buff *sb) | |
191 | { | |
192 | kfree(sb->mesg); | |
193 | kfree(sb); | |
194 | } | |
195 | ||
196 | /* | |
197 | * Get the current sync buffer if it has been created for more | |
198 | * than the specified time or the specified time is zero. | |
199 | */ | |
200 | static inline struct ip_vs_sync_buff * | |
201 | get_curr_sync_buff(unsigned long time) | |
202 | { | |
203 | struct ip_vs_sync_buff *sb; | |
204 | ||
205 | spin_lock_bh(&curr_sb_lock); | |
206 | if (curr_sb && (time == 0 || | |
207 | time_before(jiffies - curr_sb->firstuse, time))) { | |
208 | sb = curr_sb; | |
209 | curr_sb = NULL; | |
210 | } else | |
211 | sb = NULL; | |
212 | spin_unlock_bh(&curr_sb_lock); | |
213 | return sb; | |
214 | } | |
215 | ||
216 | ||
217 | /* | |
218 | * Add an ip_vs_conn information into the current sync_buff. | |
219 | * Called by ip_vs_in. | |
220 | */ | |
221 | void ip_vs_sync_conn(struct ip_vs_conn *cp) | |
222 | { | |
223 | struct ip_vs_sync_mesg *m; | |
224 | struct ip_vs_sync_conn *s; | |
225 | int len; | |
226 | ||
227 | spin_lock(&curr_sb_lock); | |
228 | if (!curr_sb) { | |
229 | if (!(curr_sb=ip_vs_sync_buff_create())) { | |
230 | spin_unlock(&curr_sb_lock); | |
231 | IP_VS_ERR("ip_vs_sync_buff_create failed.\n"); | |
232 | return; | |
233 | } | |
234 | } | |
235 | ||
236 | len = (cp->flags & IP_VS_CONN_F_SEQ_MASK) ? FULL_CONN_SIZE : | |
237 | SIMPLE_CONN_SIZE; | |
238 | m = curr_sb->mesg; | |
239 | s = (struct ip_vs_sync_conn *)curr_sb->head; | |
240 | ||
241 | /* copy members */ | |
242 | s->protocol = cp->protocol; | |
243 | s->cport = cp->cport; | |
244 | s->vport = cp->vport; | |
245 | s->dport = cp->dport; | |
246 | s->caddr = cp->caddr; | |
247 | s->vaddr = cp->vaddr; | |
248 | s->daddr = cp->daddr; | |
249 | s->flags = htons(cp->flags & ~IP_VS_CONN_F_HASHED); | |
250 | s->state = htons(cp->state); | |
251 | if (cp->flags & IP_VS_CONN_F_SEQ_MASK) { | |
252 | struct ip_vs_sync_conn_options *opt = | |
253 | (struct ip_vs_sync_conn_options *)&s[1]; | |
254 | memcpy(opt, &cp->in_seq, sizeof(*opt)); | |
255 | } | |
256 | ||
257 | m->nr_conns++; | |
258 | m->size += len; | |
259 | curr_sb->head += len; | |
260 | ||
261 | /* check if there is a space for next one */ | |
262 | if (curr_sb->head+FULL_CONN_SIZE > curr_sb->end) { | |
263 | sb_queue_tail(curr_sb); | |
264 | curr_sb = NULL; | |
265 | } | |
266 | spin_unlock(&curr_sb_lock); | |
267 | ||
268 | /* synchronize its controller if it has */ | |
269 | if (cp->control) | |
270 | ip_vs_sync_conn(cp->control); | |
271 | } | |
272 | ||
273 | ||
274 | /* | |
275 | * Process received multicast message and create the corresponding | |
276 | * ip_vs_conn entries. | |
277 | */ | |
278 | static void ip_vs_process_message(const char *buffer, const size_t buflen) | |
279 | { | |
280 | struct ip_vs_sync_mesg *m = (struct ip_vs_sync_mesg *)buffer; | |
281 | struct ip_vs_sync_conn *s; | |
282 | struct ip_vs_sync_conn_options *opt; | |
283 | struct ip_vs_conn *cp; | |
5c81833c | 284 | struct ip_vs_protocol *pp; |
1e356f9c | 285 | struct ip_vs_dest *dest; |
1da177e4 LT |
286 | char *p; |
287 | int i; | |
288 | ||
2ad17def JA |
289 | if (buflen < sizeof(struct ip_vs_sync_mesg)) { |
290 | IP_VS_ERR_RL("sync message header too short\n"); | |
291 | return; | |
292 | } | |
293 | ||
1da177e4 LT |
294 | /* Convert size back to host byte order */ |
295 | m->size = ntohs(m->size); | |
296 | ||
297 | if (buflen != m->size) { | |
2ad17def | 298 | IP_VS_ERR_RL("bogus sync message size\n"); |
1da177e4 LT |
299 | return; |
300 | } | |
301 | ||
302 | /* SyncID sanity check */ | |
303 | if (ip_vs_backup_syncid != 0 && m->syncid != ip_vs_backup_syncid) { | |
304 | IP_VS_DBG(7, "Ignoring incoming msg with syncid = %d\n", | |
305 | m->syncid); | |
306 | return; | |
307 | } | |
308 | ||
309 | p = (char *)buffer + sizeof(struct ip_vs_sync_mesg); | |
310 | for (i=0; i<m->nr_conns; i++) { | |
b209639e | 311 | unsigned flags, state; |
87375ab4 | 312 | |
2ad17def JA |
313 | if (p + SIMPLE_CONN_SIZE > buffer+buflen) { |
314 | IP_VS_ERR_RL("bogus conn in sync message\n"); | |
315 | return; | |
316 | } | |
317 | s = (struct ip_vs_sync_conn *) p; | |
7a4fbb1f | 318 | flags = ntohs(s->flags) | IP_VS_CONN_F_SYNC; |
2ad17def JA |
319 | flags &= ~IP_VS_CONN_F_HASHED; |
320 | if (flags & IP_VS_CONN_F_SEQ_MASK) { | |
321 | opt = (struct ip_vs_sync_conn_options *)&s[1]; | |
322 | p += FULL_CONN_SIZE; | |
323 | if (p > buffer+buflen) { | |
324 | IP_VS_ERR_RL("bogus conn options in sync message\n"); | |
325 | return; | |
326 | } | |
327 | } else { | |
328 | opt = NULL; | |
329 | p += SIMPLE_CONN_SIZE; | |
330 | } | |
331 | ||
b209639e | 332 | state = ntohs(s->state); |
2ad17def JA |
333 | if (!(flags & IP_VS_CONN_F_TEMPLATE)) { |
334 | pp = ip_vs_proto_get(s->protocol); | |
335 | if (!pp) { | |
336 | IP_VS_ERR_RL("Unsupported protocol %u in sync msg\n", | |
337 | s->protocol); | |
338 | continue; | |
339 | } | |
340 | if (state >= pp->num_states) { | |
341 | IP_VS_DBG(2, "Invalid %s state %u in sync msg\n", | |
342 | pp->name, state); | |
343 | continue; | |
344 | } | |
345 | } else { | |
346 | /* protocol in templates is not used for state/timeout */ | |
347 | pp = NULL; | |
348 | if (state > 0) { | |
349 | IP_VS_DBG(2, "Invalid template state %u in sync msg\n", | |
350 | state); | |
351 | state = 0; | |
352 | } | |
353 | } | |
354 | ||
87375ab4 JA |
355 | if (!(flags & IP_VS_CONN_F_TEMPLATE)) |
356 | cp = ip_vs_conn_in_get(s->protocol, | |
357 | s->caddr, s->cport, | |
358 | s->vaddr, s->vport); | |
359 | else | |
360 | cp = ip_vs_ct_in_get(s->protocol, | |
361 | s->caddr, s->cport, | |
362 | s->vaddr, s->vport); | |
1da177e4 | 363 | if (!cp) { |
1e356f9c RB |
364 | /* |
365 | * Find the appropriate destination for the connection. | |
366 | * If it is not found the connection will remain unbound | |
367 | * but still handled. | |
368 | */ | |
369 | dest = ip_vs_find_dest(s->daddr, s->dport, | |
370 | s->vaddr, s->vport, | |
371 | s->protocol); | |
b209639e RB |
372 | /* Set the approprite ativity flag */ |
373 | if (s->protocol == IPPROTO_TCP) { | |
374 | if (state != IP_VS_TCP_S_ESTABLISHED) | |
375 | flags |= IP_VS_CONN_F_INACTIVE; | |
376 | else | |
377 | flags &= ~IP_VS_CONN_F_INACTIVE; | |
378 | } | |
1da177e4 LT |
379 | cp = ip_vs_conn_new(s->protocol, |
380 | s->caddr, s->cport, | |
381 | s->vaddr, s->vport, | |
382 | s->daddr, s->dport, | |
1e356f9c RB |
383 | flags, dest); |
384 | if (dest) | |
385 | atomic_dec(&dest->refcnt); | |
1da177e4 LT |
386 | if (!cp) { |
387 | IP_VS_ERR("ip_vs_conn_new failed\n"); | |
388 | return; | |
389 | } | |
1da177e4 | 390 | } else if (!cp->dest) { |
1e356f9c | 391 | dest = ip_vs_try_bind_dest(cp); |
2ad17def | 392 | if (dest) |
1e356f9c | 393 | atomic_dec(&dest->refcnt); |
b209639e RB |
394 | } else if ((cp->dest) && (cp->protocol == IPPROTO_TCP) && |
395 | (cp->state != state)) { | |
396 | /* update active/inactive flag for the connection */ | |
397 | dest = cp->dest; | |
398 | if (!(cp->flags & IP_VS_CONN_F_INACTIVE) && | |
399 | (state != IP_VS_TCP_S_ESTABLISHED)) { | |
400 | atomic_dec(&dest->activeconns); | |
401 | atomic_inc(&dest->inactconns); | |
402 | cp->flags |= IP_VS_CONN_F_INACTIVE; | |
403 | } else if ((cp->flags & IP_VS_CONN_F_INACTIVE) && | |
404 | (state == IP_VS_TCP_S_ESTABLISHED)) { | |
405 | atomic_inc(&dest->activeconns); | |
406 | atomic_dec(&dest->inactconns); | |
407 | cp->flags &= ~IP_VS_CONN_F_INACTIVE; | |
408 | } | |
409 | } | |
1da177e4 | 410 | |
2ad17def | 411 | if (opt) |
1da177e4 | 412 | memcpy(&cp->in_seq, opt, sizeof(*opt)); |
1da177e4 | 413 | atomic_set(&cp->in_pkts, sysctl_ip_vs_sync_threshold[0]); |
b209639e | 414 | cp->state = state; |
2ad17def JA |
415 | cp->old_state = cp->state; |
416 | /* | |
417 | * We can not recover the right timeout for templates | |
418 | * in all cases, we can not find the right fwmark | |
419 | * virtual service. If needed, we can do it for | |
420 | * non-fwmark persistent services. | |
421 | */ | |
422 | if (!(flags & IP_VS_CONN_F_TEMPLATE) && pp->timeout_table) | |
423 | cp->timeout = pp->timeout_table[state]; | |
424 | else | |
425 | cp->timeout = (3*60*HZ); | |
1da177e4 | 426 | ip_vs_conn_put(cp); |
1da177e4 LT |
427 | } |
428 | } | |
429 | ||
430 | ||
431 | /* | |
432 | * Setup loopback of outgoing multicasts on a sending socket | |
433 | */ | |
434 | static void set_mcast_loop(struct sock *sk, u_char loop) | |
435 | { | |
436 | struct inet_sock *inet = inet_sk(sk); | |
437 | ||
438 | /* setsockopt(sock, SOL_IP, IP_MULTICAST_LOOP, &loop, sizeof(loop)); */ | |
439 | lock_sock(sk); | |
440 | inet->mc_loop = loop ? 1 : 0; | |
441 | release_sock(sk); | |
442 | } | |
443 | ||
444 | /* | |
445 | * Specify TTL for outgoing multicasts on a sending socket | |
446 | */ | |
447 | static void set_mcast_ttl(struct sock *sk, u_char ttl) | |
448 | { | |
449 | struct inet_sock *inet = inet_sk(sk); | |
450 | ||
451 | /* setsockopt(sock, SOL_IP, IP_MULTICAST_TTL, &ttl, sizeof(ttl)); */ | |
452 | lock_sock(sk); | |
453 | inet->mc_ttl = ttl; | |
454 | release_sock(sk); | |
455 | } | |
456 | ||
457 | /* | |
458 | * Specifiy default interface for outgoing multicasts | |
459 | */ | |
460 | static int set_mcast_if(struct sock *sk, char *ifname) | |
461 | { | |
462 | struct net_device *dev; | |
463 | struct inet_sock *inet = inet_sk(sk); | |
464 | ||
881d966b | 465 | if ((dev = __dev_get_by_name(&init_net, ifname)) == NULL) |
1da177e4 LT |
466 | return -ENODEV; |
467 | ||
468 | if (sk->sk_bound_dev_if && dev->ifindex != sk->sk_bound_dev_if) | |
469 | return -EINVAL; | |
470 | ||
471 | lock_sock(sk); | |
472 | inet->mc_index = dev->ifindex; | |
473 | /* inet->mc_addr = 0; */ | |
474 | release_sock(sk); | |
475 | ||
476 | return 0; | |
477 | } | |
478 | ||
479 | ||
480 | /* | |
481 | * Set the maximum length of sync message according to the | |
482 | * specified interface's MTU. | |
483 | */ | |
484 | static int set_sync_mesg_maxlen(int sync_state) | |
485 | { | |
486 | struct net_device *dev; | |
487 | int num; | |
488 | ||
489 | if (sync_state == IP_VS_STATE_MASTER) { | |
881d966b | 490 | if ((dev = __dev_get_by_name(&init_net, ip_vs_master_mcast_ifn)) == NULL) |
1da177e4 LT |
491 | return -ENODEV; |
492 | ||
493 | num = (dev->mtu - sizeof(struct iphdr) - | |
494 | sizeof(struct udphdr) - | |
495 | SYNC_MESG_HEADER_LEN - 20) / SIMPLE_CONN_SIZE; | |
496 | sync_send_mesg_maxlen = | |
497 | SYNC_MESG_HEADER_LEN + SIMPLE_CONN_SIZE * num; | |
498 | IP_VS_DBG(7, "setting the maximum length of sync sending " | |
499 | "message %d.\n", sync_send_mesg_maxlen); | |
500 | } else if (sync_state == IP_VS_STATE_BACKUP) { | |
881d966b | 501 | if ((dev = __dev_get_by_name(&init_net, ip_vs_backup_mcast_ifn)) == NULL) |
1da177e4 LT |
502 | return -ENODEV; |
503 | ||
504 | sync_recv_mesg_maxlen = dev->mtu - | |
505 | sizeof(struct iphdr) - sizeof(struct udphdr); | |
506 | IP_VS_DBG(7, "setting the maximum length of sync receiving " | |
507 | "message %d.\n", sync_recv_mesg_maxlen); | |
508 | } | |
509 | ||
510 | return 0; | |
511 | } | |
512 | ||
513 | ||
514 | /* | |
515 | * Join a multicast group. | |
516 | * the group is specified by a class D multicast address 224.0.0.0/8 | |
517 | * in the in_addr structure passed in as a parameter. | |
518 | */ | |
519 | static int | |
520 | join_mcast_group(struct sock *sk, struct in_addr *addr, char *ifname) | |
521 | { | |
522 | struct ip_mreqn mreq; | |
523 | struct net_device *dev; | |
524 | int ret; | |
525 | ||
526 | memset(&mreq, 0, sizeof(mreq)); | |
527 | memcpy(&mreq.imr_multiaddr, addr, sizeof(struct in_addr)); | |
528 | ||
881d966b | 529 | if ((dev = __dev_get_by_name(&init_net, ifname)) == NULL) |
1da177e4 LT |
530 | return -ENODEV; |
531 | if (sk->sk_bound_dev_if && dev->ifindex != sk->sk_bound_dev_if) | |
532 | return -EINVAL; | |
533 | ||
534 | mreq.imr_ifindex = dev->ifindex; | |
535 | ||
536 | lock_sock(sk); | |
537 | ret = ip_mc_join_group(sk, &mreq); | |
538 | release_sock(sk); | |
539 | ||
540 | return ret; | |
541 | } | |
542 | ||
543 | ||
544 | static int bind_mcastif_addr(struct socket *sock, char *ifname) | |
545 | { | |
546 | struct net_device *dev; | |
a61ced5d | 547 | __be32 addr; |
1da177e4 LT |
548 | struct sockaddr_in sin; |
549 | ||
881d966b | 550 | if ((dev = __dev_get_by_name(&init_net, ifname)) == NULL) |
1da177e4 LT |
551 | return -ENODEV; |
552 | ||
553 | addr = inet_select_addr(dev, 0, RT_SCOPE_UNIVERSE); | |
554 | if (!addr) | |
555 | IP_VS_ERR("You probably need to specify IP address on " | |
556 | "multicast interface.\n"); | |
557 | ||
558 | IP_VS_DBG(7, "binding socket with (%s) %u.%u.%u.%u\n", | |
559 | ifname, NIPQUAD(addr)); | |
560 | ||
561 | /* Now bind the socket with the address of multicast interface */ | |
562 | sin.sin_family = AF_INET; | |
563 | sin.sin_addr.s_addr = addr; | |
564 | sin.sin_port = 0; | |
565 | ||
566 | return sock->ops->bind(sock, (struct sockaddr*)&sin, sizeof(sin)); | |
567 | } | |
568 | ||
569 | /* | |
570 | * Set up sending multicast socket over UDP | |
571 | */ | |
572 | static struct socket * make_send_sock(void) | |
573 | { | |
574 | struct socket *sock; | |
575 | ||
576 | /* First create a socket */ | |
577 | if (sock_create_kern(PF_INET, SOCK_DGRAM, IPPROTO_UDP, &sock) < 0) { | |
578 | IP_VS_ERR("Error during creation of socket; terminating\n"); | |
579 | return NULL; | |
580 | } | |
581 | ||
582 | if (set_mcast_if(sock->sk, ip_vs_master_mcast_ifn) < 0) { | |
583 | IP_VS_ERR("Error setting outbound mcast interface\n"); | |
584 | goto error; | |
585 | } | |
586 | ||
587 | set_mcast_loop(sock->sk, 0); | |
588 | set_mcast_ttl(sock->sk, 1); | |
589 | ||
590 | if (bind_mcastif_addr(sock, ip_vs_master_mcast_ifn) < 0) { | |
591 | IP_VS_ERR("Error binding address of the mcast interface\n"); | |
592 | goto error; | |
593 | } | |
594 | ||
595 | if (sock->ops->connect(sock, | |
596 | (struct sockaddr*)&mcast_addr, | |
597 | sizeof(struct sockaddr), 0) < 0) { | |
598 | IP_VS_ERR("Error connecting to the multicast addr\n"); | |
599 | goto error; | |
600 | } | |
601 | ||
602 | return sock; | |
603 | ||
604 | error: | |
605 | sock_release(sock); | |
606 | return NULL; | |
607 | } | |
608 | ||
609 | ||
610 | /* | |
611 | * Set up receiving multicast socket over UDP | |
612 | */ | |
613 | static struct socket * make_receive_sock(void) | |
614 | { | |
615 | struct socket *sock; | |
616 | ||
617 | /* First create a socket */ | |
618 | if (sock_create_kern(PF_INET, SOCK_DGRAM, IPPROTO_UDP, &sock) < 0) { | |
619 | IP_VS_ERR("Error during creation of socket; terminating\n"); | |
620 | return NULL; | |
621 | } | |
622 | ||
623 | /* it is equivalent to the REUSEADDR option in user-space */ | |
624 | sock->sk->sk_reuse = 1; | |
625 | ||
626 | if (sock->ops->bind(sock, | |
627 | (struct sockaddr*)&mcast_addr, | |
628 | sizeof(struct sockaddr)) < 0) { | |
629 | IP_VS_ERR("Error binding to the multicast addr\n"); | |
630 | goto error; | |
631 | } | |
632 | ||
633 | /* join the multicast group */ | |
634 | if (join_mcast_group(sock->sk, | |
635 | (struct in_addr*)&mcast_addr.sin_addr, | |
636 | ip_vs_backup_mcast_ifn) < 0) { | |
637 | IP_VS_ERR("Error joining to the multicast group\n"); | |
638 | goto error; | |
639 | } | |
640 | ||
641 | return sock; | |
642 | ||
643 | error: | |
644 | sock_release(sock); | |
645 | return NULL; | |
646 | } | |
647 | ||
648 | ||
649 | static int | |
650 | ip_vs_send_async(struct socket *sock, const char *buffer, const size_t length) | |
651 | { | |
652 | struct msghdr msg = {.msg_flags = MSG_DONTWAIT|MSG_NOSIGNAL}; | |
653 | struct kvec iov; | |
654 | int len; | |
655 | ||
656 | EnterFunction(7); | |
657 | iov.iov_base = (void *)buffer; | |
658 | iov.iov_len = length; | |
659 | ||
660 | len = kernel_sendmsg(sock, &msg, &iov, 1, (size_t)(length)); | |
661 | ||
662 | LeaveFunction(7); | |
663 | return len; | |
664 | } | |
665 | ||
666 | static void | |
667 | ip_vs_send_sync_msg(struct socket *sock, struct ip_vs_sync_mesg *msg) | |
668 | { | |
669 | int msize; | |
670 | ||
671 | msize = msg->size; | |
672 | ||
673 | /* Put size in network byte order */ | |
674 | msg->size = htons(msg->size); | |
675 | ||
676 | if (ip_vs_send_async(sock, (char *)msg, msize) != msize) | |
677 | IP_VS_ERR("ip_vs_send_async error\n"); | |
678 | } | |
679 | ||
680 | static int | |
681 | ip_vs_receive(struct socket *sock, char *buffer, const size_t buflen) | |
682 | { | |
683 | struct msghdr msg = {NULL,}; | |
684 | struct kvec iov; | |
685 | int len; | |
686 | ||
687 | EnterFunction(7); | |
688 | ||
689 | /* Receive a packet */ | |
690 | iov.iov_base = buffer; | |
691 | iov.iov_len = (size_t)buflen; | |
692 | ||
693 | len = kernel_recvmsg(sock, &msg, &iov, 1, buflen, 0); | |
694 | ||
695 | if (len < 0) | |
696 | return -1; | |
697 | ||
698 | LeaveFunction(7); | |
699 | return len; | |
700 | } | |
701 | ||
702 | ||
703 | static DECLARE_WAIT_QUEUE_HEAD(sync_wait); | |
704 | static pid_t sync_master_pid = 0; | |
705 | static pid_t sync_backup_pid = 0; | |
706 | ||
707 | static DECLARE_WAIT_QUEUE_HEAD(stop_sync_wait); | |
708 | static int stop_master_sync = 0; | |
709 | static int stop_backup_sync = 0; | |
710 | ||
711 | static void sync_master_loop(void) | |
712 | { | |
713 | struct socket *sock; | |
714 | struct ip_vs_sync_buff *sb; | |
715 | ||
716 | /* create the sending multicast socket */ | |
717 | sock = make_send_sock(); | |
718 | if (!sock) | |
719 | return; | |
720 | ||
721 | IP_VS_INFO("sync thread started: state = MASTER, mcast_ifn = %s, " | |
722 | "syncid = %d\n", | |
723 | ip_vs_master_mcast_ifn, ip_vs_master_syncid); | |
724 | ||
725 | for (;;) { | |
726 | while ((sb=sb_dequeue())) { | |
727 | ip_vs_send_sync_msg(sock, sb->mesg); | |
728 | ip_vs_sync_buff_release(sb); | |
729 | } | |
730 | ||
731 | /* check if entries stay in curr_sb for 2 seconds */ | |
732 | if ((sb = get_curr_sync_buff(2*HZ))) { | |
733 | ip_vs_send_sync_msg(sock, sb->mesg); | |
734 | ip_vs_sync_buff_release(sb); | |
735 | } | |
736 | ||
737 | if (stop_master_sync) | |
738 | break; | |
739 | ||
89eaeb09 | 740 | msleep_interruptible(1000); |
1da177e4 LT |
741 | } |
742 | ||
743 | /* clean up the sync_buff queue */ | |
744 | while ((sb=sb_dequeue())) { | |
745 | ip_vs_sync_buff_release(sb); | |
746 | } | |
747 | ||
748 | /* clean up the current sync_buff */ | |
749 | if ((sb = get_curr_sync_buff(0))) { | |
750 | ip_vs_sync_buff_release(sb); | |
751 | } | |
752 | ||
753 | /* release the sending multicast socket */ | |
754 | sock_release(sock); | |
755 | } | |
756 | ||
757 | ||
758 | static void sync_backup_loop(void) | |
759 | { | |
760 | struct socket *sock; | |
761 | char *buf; | |
762 | int len; | |
763 | ||
764 | if (!(buf = kmalloc(sync_recv_mesg_maxlen, GFP_ATOMIC))) { | |
765 | IP_VS_ERR("sync_backup_loop: kmalloc error\n"); | |
766 | return; | |
767 | } | |
768 | ||
769 | /* create the receiving multicast socket */ | |
770 | sock = make_receive_sock(); | |
771 | if (!sock) | |
772 | goto out; | |
773 | ||
774 | IP_VS_INFO("sync thread started: state = BACKUP, mcast_ifn = %s, " | |
775 | "syncid = %d\n", | |
776 | ip_vs_backup_mcast_ifn, ip_vs_backup_syncid); | |
777 | ||
778 | for (;;) { | |
779 | /* do you have data now? */ | |
780 | while (!skb_queue_empty(&(sock->sk->sk_receive_queue))) { | |
781 | if ((len = | |
782 | ip_vs_receive(sock, buf, | |
783 | sync_recv_mesg_maxlen)) <= 0) { | |
784 | IP_VS_ERR("receiving message error\n"); | |
785 | break; | |
786 | } | |
787 | /* disable bottom half, because it accessed the data | |
788 | shared by softirq while getting/creating conns */ | |
789 | local_bh_disable(); | |
790 | ip_vs_process_message(buf, len); | |
791 | local_bh_enable(); | |
792 | } | |
793 | ||
794 | if (stop_backup_sync) | |
795 | break; | |
796 | ||
89eaeb09 | 797 | msleep_interruptible(1000); |
1da177e4 LT |
798 | } |
799 | ||
800 | /* release the sending multicast socket */ | |
801 | sock_release(sock); | |
802 | ||
803 | out: | |
804 | kfree(buf); | |
805 | } | |
806 | ||
807 | ||
808 | static void set_sync_pid(int sync_state, pid_t sync_pid) | |
809 | { | |
810 | if (sync_state == IP_VS_STATE_MASTER) | |
811 | sync_master_pid = sync_pid; | |
812 | else if (sync_state == IP_VS_STATE_BACKUP) | |
813 | sync_backup_pid = sync_pid; | |
814 | } | |
815 | ||
816 | static void set_stop_sync(int sync_state, int set) | |
817 | { | |
818 | if (sync_state == IP_VS_STATE_MASTER) | |
819 | stop_master_sync = set; | |
820 | else if (sync_state == IP_VS_STATE_BACKUP) | |
821 | stop_backup_sync = set; | |
822 | else { | |
823 | stop_master_sync = set; | |
824 | stop_backup_sync = set; | |
825 | } | |
826 | } | |
827 | ||
828 | static int sync_thread(void *startup) | |
829 | { | |
830 | DECLARE_WAITQUEUE(wait, current); | |
831 | mm_segment_t oldmm; | |
832 | int state; | |
833 | const char *name; | |
cc0191ae | 834 | struct ip_vs_sync_thread_data *tinfo = startup; |
1da177e4 LT |
835 | |
836 | /* increase the module use count */ | |
837 | ip_vs_use_count_inc(); | |
838 | ||
839 | if (ip_vs_sync_state & IP_VS_STATE_MASTER && !sync_master_pid) { | |
840 | state = IP_VS_STATE_MASTER; | |
841 | name = "ipvs_syncmaster"; | |
842 | } else if (ip_vs_sync_state & IP_VS_STATE_BACKUP && !sync_backup_pid) { | |
843 | state = IP_VS_STATE_BACKUP; | |
844 | name = "ipvs_syncbackup"; | |
845 | } else { | |
846 | IP_VS_BUG(); | |
847 | ip_vs_use_count_dec(); | |
848 | return -EINVAL; | |
849 | } | |
850 | ||
851 | daemonize(name); | |
852 | ||
853 | oldmm = get_fs(); | |
854 | set_fs(KERNEL_DS); | |
855 | ||
856 | /* Block all signals */ | |
857 | spin_lock_irq(¤t->sighand->siglock); | |
858 | siginitsetinv(¤t->blocked, 0); | |
859 | recalc_sigpending(); | |
860 | spin_unlock_irq(¤t->sighand->siglock); | |
861 | ||
862 | /* set the maximum length of sync message */ | |
863 | set_sync_mesg_maxlen(state); | |
864 | ||
865 | /* set up multicast address */ | |
866 | mcast_addr.sin_family = AF_INET; | |
867 | mcast_addr.sin_port = htons(IP_VS_SYNC_PORT); | |
868 | mcast_addr.sin_addr.s_addr = htonl(IP_VS_SYNC_GROUP); | |
869 | ||
870 | add_wait_queue(&sync_wait, &wait); | |
871 | ||
6651fd56 | 872 | set_sync_pid(state, task_pid_nr(current)); |
cc0191ae NH |
873 | complete(tinfo->startup); |
874 | ||
875 | /* | |
876 | * once we call the completion queue above, we should | |
877 | * null out that reference, since its allocated on the | |
878 | * stack of the creating kernel thread | |
879 | */ | |
880 | tinfo->startup = NULL; | |
1da177e4 LT |
881 | |
882 | /* processing master/backup loop here */ | |
883 | if (state == IP_VS_STATE_MASTER) | |
884 | sync_master_loop(); | |
885 | else if (state == IP_VS_STATE_BACKUP) | |
886 | sync_backup_loop(); | |
887 | else IP_VS_BUG(); | |
888 | ||
889 | remove_wait_queue(&sync_wait, &wait); | |
890 | ||
891 | /* thread exits */ | |
cc0191ae NH |
892 | |
893 | /* | |
894 | * If we weren't explicitly stopped, then we | |
895 | * exited in error, and should undo our state | |
896 | */ | |
897 | if ((!stop_master_sync) && (!stop_backup_sync)) | |
898 | ip_vs_sync_state -= tinfo->state; | |
899 | ||
1da177e4 LT |
900 | set_sync_pid(state, 0); |
901 | IP_VS_INFO("sync thread stopped!\n"); | |
902 | ||
903 | set_fs(oldmm); | |
904 | ||
905 | /* decrease the module use count */ | |
906 | ip_vs_use_count_dec(); | |
907 | ||
908 | set_stop_sync(state, 0); | |
909 | wake_up(&stop_sync_wait); | |
910 | ||
cc0191ae NH |
911 | /* |
912 | * we need to free the structure that was allocated | |
913 | * for us in start_sync_thread | |
914 | */ | |
915 | kfree(tinfo); | |
1da177e4 LT |
916 | return 0; |
917 | } | |
918 | ||
919 | ||
920 | static int fork_sync_thread(void *startup) | |
921 | { | |
922 | pid_t pid; | |
923 | ||
924 | /* fork the sync thread here, then the parent process of the | |
925 | sync thread is the init process after this thread exits. */ | |
926 | repeat: | |
927 | if ((pid = kernel_thread(sync_thread, startup, 0)) < 0) { | |
928 | IP_VS_ERR("could not create sync_thread due to %d... " | |
929 | "retrying.\n", pid); | |
89eaeb09 | 930 | msleep_interruptible(1000); |
1da177e4 LT |
931 | goto repeat; |
932 | } | |
933 | ||
934 | return 0; | |
935 | } | |
936 | ||
937 | ||
938 | int start_sync_thread(int state, char *mcast_ifn, __u8 syncid) | |
939 | { | |
6e9a4738 | 940 | DECLARE_COMPLETION_ONSTACK(startup); |
1da177e4 | 941 | pid_t pid; |
cc0191ae | 942 | struct ip_vs_sync_thread_data *tinfo; |
1da177e4 LT |
943 | |
944 | if ((state == IP_VS_STATE_MASTER && sync_master_pid) || | |
945 | (state == IP_VS_STATE_BACKUP && sync_backup_pid)) | |
946 | return -EEXIST; | |
947 | ||
cc0191ae NH |
948 | /* |
949 | * Note that tinfo will be freed in sync_thread on exit | |
950 | */ | |
951 | tinfo = kmalloc(sizeof(struct ip_vs_sync_thread_data), GFP_KERNEL); | |
952 | if (!tinfo) | |
953 | return -ENOMEM; | |
954 | ||
0dc47877 | 955 | IP_VS_DBG(7, "%s: pid %d\n", __func__, task_pid_nr(current)); |
1da177e4 LT |
956 | IP_VS_DBG(7, "Each ip_vs_sync_conn entry need %Zd bytes\n", |
957 | sizeof(struct ip_vs_sync_conn)); | |
958 | ||
959 | ip_vs_sync_state |= state; | |
960 | if (state == IP_VS_STATE_MASTER) { | |
37004af3 SH |
961 | strlcpy(ip_vs_master_mcast_ifn, mcast_ifn, |
962 | sizeof(ip_vs_master_mcast_ifn)); | |
1da177e4 LT |
963 | ip_vs_master_syncid = syncid; |
964 | } else { | |
37004af3 SH |
965 | strlcpy(ip_vs_backup_mcast_ifn, mcast_ifn, |
966 | sizeof(ip_vs_backup_mcast_ifn)); | |
1da177e4 LT |
967 | ip_vs_backup_syncid = syncid; |
968 | } | |
969 | ||
cc0191ae NH |
970 | tinfo->state = state; |
971 | tinfo->startup = &startup; | |
972 | ||
1da177e4 | 973 | repeat: |
cc0191ae | 974 | if ((pid = kernel_thread(fork_sync_thread, tinfo, 0)) < 0) { |
1da177e4 LT |
975 | IP_VS_ERR("could not create fork_sync_thread due to %d... " |
976 | "retrying.\n", pid); | |
89eaeb09 | 977 | msleep_interruptible(1000); |
1da177e4 LT |
978 | goto repeat; |
979 | } | |
980 | ||
981 | wait_for_completion(&startup); | |
982 | ||
983 | return 0; | |
984 | } | |
985 | ||
986 | ||
987 | int stop_sync_thread(int state) | |
988 | { | |
989 | DECLARE_WAITQUEUE(wait, current); | |
990 | ||
991 | if ((state == IP_VS_STATE_MASTER && !sync_master_pid) || | |
992 | (state == IP_VS_STATE_BACKUP && !sync_backup_pid)) | |
993 | return -ESRCH; | |
994 | ||
0dc47877 | 995 | IP_VS_DBG(7, "%s: pid %d\n", __func__, task_pid_nr(current)); |
1da177e4 | 996 | IP_VS_INFO("stopping sync thread %d ...\n", |
37004af3 SH |
997 | (state == IP_VS_STATE_MASTER) ? |
998 | sync_master_pid : sync_backup_pid); | |
1da177e4 LT |
999 | |
1000 | __set_current_state(TASK_UNINTERRUPTIBLE); | |
1001 | add_wait_queue(&stop_sync_wait, &wait); | |
1002 | set_stop_sync(state, 1); | |
1003 | ip_vs_sync_state -= state; | |
1004 | wake_up(&sync_wait); | |
1005 | schedule(); | |
1006 | __set_current_state(TASK_RUNNING); | |
1007 | remove_wait_queue(&stop_sync_wait, &wait); | |
1008 | ||
1009 | /* Note: no need to reap the sync thread, because its parent | |
1010 | process is the init process */ | |
1011 | ||
1012 | if ((state == IP_VS_STATE_MASTER && stop_master_sync) || | |
1013 | (state == IP_VS_STATE_BACKUP && stop_backup_sync)) | |
1014 | IP_VS_BUG(); | |
1015 | ||
1016 | return 0; | |
1017 | } |