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Merge tag 'gpio-v3.13-3' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw...
[linux-2.6.git] / net / ipv4 / netfilter / ipt_CLUSTERIP.c
blob2510c02c2d2168ffcd27f286c7eab3ca75165f26
1 /* Cluster IP hashmark target
2 * (C) 2003-2004 by Harald Welte <laforge@netfilter.org>
3 * based on ideas of Fabio Olive Leite <olive@unixforge.org>
4 *
5 * Development of this code funded by SuSE Linux AG, http://www.suse.com/
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License version 2 as
9 * published by the Free Software Foundation.
10 *
11 */
12 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
13 #include <linux/module.h>
14 #include <linux/proc_fs.h>
15 #include <linux/jhash.h>
16 #include <linux/bitops.h>
17 #include <linux/skbuff.h>
18 #include <linux/slab.h>
19 #include <linux/ip.h>
20 #include <linux/tcp.h>
21 #include <linux/udp.h>
22 #include <linux/icmp.h>
23 #include <linux/if_arp.h>
24 #include <linux/seq_file.h>
25 #include <linux/netfilter_arp.h>
26 #include <linux/netfilter/x_tables.h>
27 #include <linux/netfilter_ipv4/ip_tables.h>
28 #include <linux/netfilter_ipv4/ipt_CLUSTERIP.h>
29 #include <net/netfilter/nf_conntrack.h>
30 #include <net/net_namespace.h>
31 #include <net/netns/generic.h>
32 #include <net/checksum.h>
33 #include <net/ip.h>
34
35 #define CLUSTERIP_VERSION "0.8"
36
37 MODULE_LICENSE("GPL");
38 MODULE_AUTHOR("Harald Welte <laforge@netfilter.org>");
39 MODULE_DESCRIPTION("Xtables: CLUSTERIP target");
40
41 struct clusterip_config {
42 struct list_head list; /* list of all configs */
43 atomic_t refcount; /* reference count */
44 atomic_t entries; /* number of entries/rules
45 * referencing us */
46
47 __be32 clusterip; /* the IP address */
48 u_int8_t clustermac[ETH_ALEN]; /* the MAC address */
49 struct net_device *dev; /* device */
50 u_int16_t num_total_nodes; /* total number of nodes */
51 unsigned long local_nodes; /* node number array */
52
53 #ifdef CONFIG_PROC_FS
54 struct proc_dir_entry *pde; /* proc dir entry */
55 #endif
56 enum clusterip_hashmode hash_mode; /* which hashing mode */
57 u_int32_t hash_initval; /* hash initialization */
58 struct rcu_head rcu;
59 };
60
61 #ifdef CONFIG_PROC_FS
62 static const struct file_operations clusterip_proc_fops;
63 #endif
64
65 static int clusterip_net_id __read_mostly;
66
67 struct clusterip_net {
68 struct list_head configs;
69 /* lock protects the configs list */
70 spinlock_t lock;
71
72 #ifdef CONFIG_PROC_FS
73 struct proc_dir_entry *procdir;
74 #endif
75 };
76
77 static inline void
78 clusterip_config_get(struct clusterip_config *c)
79 {
80 atomic_inc(&c->refcount);
81 }
82
83
84 static void clusterip_config_rcu_free(struct rcu_head *head)
85 {
86 kfree(container_of(head, struct clusterip_config, rcu));
87 }
88
89 static inline void
90 clusterip_config_put(struct clusterip_config *c)
91 {
92 if (atomic_dec_and_test(&c->refcount))
93 call_rcu_bh(&c->rcu, clusterip_config_rcu_free);
94 }
95
96 /* decrease the count of entries using/referencing this config. If last
97 * entry(rule) is removed, remove the config from lists, but don't free it
98 * yet, since proc-files could still be holding references */
99 static inline void
100 clusterip_config_entry_put(struct clusterip_config *c)
101 {
102 struct net *net = dev_net(c->dev);
103 struct clusterip_net *cn = net_generic(net, clusterip_net_id);
104
105 local_bh_disable();
106 if (atomic_dec_and_lock(&c->entries, &cn->lock)) {
107 list_del_rcu(&c->list);
108 spin_unlock(&cn->lock);
109 local_bh_enable();
110
111 dev_mc_del(c->dev, c->clustermac);
112 dev_put(c->dev);
113
114 /* In case anyone still accesses the file, the open/close
115 * functions are also incrementing the refcount on their own,
116 * so it's safe to remove the entry even if it's in use. */
117 #ifdef CONFIG_PROC_FS
118 proc_remove(c->pde);
119 #endif
120 return;
121 }
122 local_bh_enable();
123 }
124
125 static struct clusterip_config *
126 __clusterip_config_find(struct net *net, __be32 clusterip)
127 {
128 struct clusterip_config *c;
129 struct clusterip_net *cn = net_generic(net, clusterip_net_id);
130
131 list_for_each_entry_rcu(c, &cn->configs, list) {
132 if (c->clusterip == clusterip)
133 return c;
134 }
135
136 return NULL;
137 }
138
139 static inline struct clusterip_config *
140 clusterip_config_find_get(struct net *net, __be32 clusterip, int entry)
141 {
142 struct clusterip_config *c;
143
144 rcu_read_lock_bh();
145 c = __clusterip_config_find(net, clusterip);
146 if (c) {
147 if (unlikely(!atomic_inc_not_zero(&c->refcount)))
148 c = NULL;
149 else if (entry)
150 atomic_inc(&c->entries);
151 }
152 rcu_read_unlock_bh();
153
154 return c;
155 }
156
157 static void
158 clusterip_config_init_nodelist(struct clusterip_config *c,
159 const struct ipt_clusterip_tgt_info *i)
160 {
161 int n;
162
163 for (n = 0; n < i->num_local_nodes; n++)
164 set_bit(i->local_nodes[n] - 1, &c->local_nodes);
165 }
166
167 static struct clusterip_config *
168 clusterip_config_init(const struct ipt_clusterip_tgt_info *i, __be32 ip,
169 struct net_device *dev)
170 {
171 struct clusterip_config *c;
172 struct clusterip_net *cn = net_generic(dev_net(dev), clusterip_net_id);
173
174 c = kzalloc(sizeof(*c), GFP_ATOMIC);
175 if (!c)
176 return NULL;
177
178 c->dev = dev;
179 c->clusterip = ip;
180 memcpy(&c->clustermac, &i->clustermac, ETH_ALEN);
181 c->num_total_nodes = i->num_total_nodes;
182 clusterip_config_init_nodelist(c, i);
183 c->hash_mode = i->hash_mode;
184 c->hash_initval = i->hash_initval;
185 atomic_set(&c->refcount, 1);
186 atomic_set(&c->entries, 1);
187
188 #ifdef CONFIG_PROC_FS
189 {
190 char buffer[16];
191
192 /* create proc dir entry */
193 sprintf(buffer, "%pI4", &ip);
194 c->pde = proc_create_data(buffer, S_IWUSR|S_IRUSR,
195 cn->procdir,
196 &clusterip_proc_fops, c);
197 if (!c->pde) {
198 kfree(c);
199 return NULL;
200 }
201 }
202 #endif
203
204 spin_lock_bh(&cn->lock);
205 list_add_rcu(&c->list, &cn->configs);
206 spin_unlock_bh(&cn->lock);
207
208 return c;
209 }
210
211 #ifdef CONFIG_PROC_FS
212 static int
213 clusterip_add_node(struct clusterip_config *c, u_int16_t nodenum)
214 {
215
216 if (nodenum == 0 ||
217 nodenum > c->num_total_nodes)
218 return 1;
219
220 /* check if we already have this number in our bitfield */
221 if (test_and_set_bit(nodenum - 1, &c->local_nodes))
222 return 1;
223
224 return 0;
225 }
226
227 static bool
228 clusterip_del_node(struct clusterip_config *c, u_int16_t nodenum)
229 {
230 if (nodenum == 0 ||
231 nodenum > c->num_total_nodes)
232 return true;
233
234 if (test_and_clear_bit(nodenum - 1, &c->local_nodes))
235 return false;
236
237 return true;
238 }
239 #endif
240
241 static inline u_int32_t
242 clusterip_hashfn(const struct sk_buff *skb,
243 const struct clusterip_config *config)
244 {
245 const struct iphdr *iph = ip_hdr(skb);
246 unsigned long hashval;
247 u_int16_t sport = 0, dport = 0;
248 int poff;
249
250 poff = proto_ports_offset(iph->protocol);
251 if (poff >= 0) {
252 const u_int16_t *ports;
253 u16 _ports[2];
254
255 ports = skb_header_pointer(skb, iph->ihl * 4 + poff, 4, _ports);
256 if (ports) {
257 sport = ports[0];
258 dport = ports[1];
259 }
260 } else {
261 net_info_ratelimited("unknown protocol %u\n", iph->protocol);
262 }
263
264 switch (config->hash_mode) {
265 case CLUSTERIP_HASHMODE_SIP:
266 hashval = jhash_1word(ntohl(iph->saddr),
267 config->hash_initval);
268 break;
269 case CLUSTERIP_HASHMODE_SIP_SPT:
270 hashval = jhash_2words(ntohl(iph->saddr), sport,
271 config->hash_initval);
272 break;
273 case CLUSTERIP_HASHMODE_SIP_SPT_DPT:
274 hashval = jhash_3words(ntohl(iph->saddr), sport, dport,
275 config->hash_initval);
276 break;
277 default:
278 /* to make gcc happy */
279 hashval = 0;
280 /* This cannot happen, unless the check function wasn't called
281 * at rule load time */
282 pr_info("unknown mode %u\n", config->hash_mode);
283 BUG();
284 break;
285 }
286
287 /* node numbers are 1..n, not 0..n */
288 return (((u64)hashval * config->num_total_nodes) >> 32) + 1;
289 }
290
291 static inline int
292 clusterip_responsible(const struct clusterip_config *config, u_int32_t hash)
293 {
294 return test_bit(hash - 1, &config->local_nodes);
295 }
296
297 /***********************************************************************
298 * IPTABLES TARGET
299 ***********************************************************************/
300
301 static unsigned int
302 clusterip_tg(struct sk_buff *skb, const struct xt_action_param *par)
303 {
304 const struct ipt_clusterip_tgt_info *cipinfo = par->targinfo;
305 struct nf_conn *ct;
306 enum ip_conntrack_info ctinfo;
307 u_int32_t hash;
308
309 /* don't need to clusterip_config_get() here, since refcount
310 * is only decremented by destroy() - and ip_tables guarantees
311 * that the ->target() function isn't called after ->destroy() */
312
313 ct = nf_ct_get(skb, &ctinfo);
314 if (ct == NULL)
315 return NF_DROP;
316
317 /* special case: ICMP error handling. conntrack distinguishes between
318 * error messages (RELATED) and information requests (see below) */
319 if (ip_hdr(skb)->protocol == IPPROTO_ICMP &&
320 (ctinfo == IP_CT_RELATED ||
321 ctinfo == IP_CT_RELATED_REPLY))
322 return XT_CONTINUE;
323
324 /* ip_conntrack_icmp guarantees us that we only have ICMP_ECHO,
325 * TIMESTAMP, INFO_REQUEST or ADDRESS type icmp packets from here
326 * on, which all have an ID field [relevant for hashing]. */
327
328 hash = clusterip_hashfn(skb, cipinfo->config);
329
330 switch (ctinfo) {
331 case IP_CT_NEW:
332 ct->mark = hash;
333 break;
334 case IP_CT_RELATED:
335 case IP_CT_RELATED_REPLY:
336 /* FIXME: we don't handle expectations at the moment.
337 * They can arrive on a different node than
338 * the master connection (e.g. FTP passive mode) */
339 case IP_CT_ESTABLISHED:
340 case IP_CT_ESTABLISHED_REPLY:
341 break;
342 default: /* Prevent gcc warnings */
343 break;
344 }
345
346 #ifdef DEBUG
347 nf_ct_dump_tuple_ip(&ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple);
348 #endif
349 pr_debug("hash=%u ct_hash=%u ", hash, ct->mark);
350 if (!clusterip_responsible(cipinfo->config, hash)) {
351 pr_debug("not responsible\n");
352 return NF_DROP;
353 }
354 pr_debug("responsible\n");
355
356 /* despite being received via linklayer multicast, this is
357 * actually a unicast IP packet. TCP doesn't like PACKET_MULTICAST */
358 skb->pkt_type = PACKET_HOST;
359
360 return XT_CONTINUE;
361 }
362
363 static int clusterip_tg_check(const struct xt_tgchk_param *par)
364 {
365 struct ipt_clusterip_tgt_info *cipinfo = par->targinfo;
366 const struct ipt_entry *e = par->entryinfo;
367 struct clusterip_config *config;
368 int ret;
369
370 if (cipinfo->hash_mode != CLUSTERIP_HASHMODE_SIP &&
371 cipinfo->hash_mode != CLUSTERIP_HASHMODE_SIP_SPT &&
372 cipinfo->hash_mode != CLUSTERIP_HASHMODE_SIP_SPT_DPT) {
373 pr_info("unknown mode %u\n", cipinfo->hash_mode);
374 return -EINVAL;
375
376 }
377 if (e->ip.dmsk.s_addr != htonl(0xffffffff) ||
378 e->ip.dst.s_addr == 0) {
379 pr_info("Please specify destination IP\n");
380 return -EINVAL;
381 }
382
383 /* FIXME: further sanity checks */
384
385 config = clusterip_config_find_get(par->net, e->ip.dst.s_addr, 1);
386 if (!config) {
387 if (!(cipinfo->flags & CLUSTERIP_FLAG_NEW)) {
388 pr_info("no config found for %pI4, need 'new'\n",
389 &e->ip.dst.s_addr);
390 return -EINVAL;
391 } else {
392 struct net_device *dev;
393
394 if (e->ip.iniface[0] == '\0') {
395 pr_info("Please specify an interface name\n");
396 return -EINVAL;
397 }
398
399 dev = dev_get_by_name(par->net, e->ip.iniface);
400 if (!dev) {
401 pr_info("no such interface %s\n",
402 e->ip.iniface);
403 return -ENOENT;
404 }
405
406 config = clusterip_config_init(cipinfo,
407 e->ip.dst.s_addr, dev);
408 if (!config) {
409 dev_put(dev);
410 return -ENOMEM;
411 }
412 dev_mc_add(config->dev, config->clustermac);
413 }
414 }
415 cipinfo->config = config;
416
417 ret = nf_ct_l3proto_try_module_get(par->family);
418 if (ret < 0)
419 pr_info("cannot load conntrack support for proto=%u\n",
420 par->family);
421 return ret;
422 }
423
424 /* drop reference count of cluster config when rule is deleted */
425 static void clusterip_tg_destroy(const struct xt_tgdtor_param *par)
426 {
427 const struct ipt_clusterip_tgt_info *cipinfo = par->targinfo;
428
429 /* if no more entries are referencing the config, remove it
430 * from the list and destroy the proc entry */
431 clusterip_config_entry_put(cipinfo->config);
432
433 clusterip_config_put(cipinfo->config);
434
435 nf_ct_l3proto_module_put(par->family);
436 }
437
438 #ifdef CONFIG_COMPAT
439 struct compat_ipt_clusterip_tgt_info
440 {
441 u_int32_t flags;
442 u_int8_t clustermac[6];
443 u_int16_t num_total_nodes;
444 u_int16_t num_local_nodes;
445 u_int16_t local_nodes[CLUSTERIP_MAX_NODES];
446 u_int32_t hash_mode;
447 u_int32_t hash_initval;
448 compat_uptr_t config;
449 };
450 #endif /* CONFIG_COMPAT */
451
452 static struct xt_target clusterip_tg_reg __read_mostly = {
453 .name = "CLUSTERIP",
454 .family = NFPROTO_IPV4,
455 .target = clusterip_tg,
456 .checkentry = clusterip_tg_check,
457 .destroy = clusterip_tg_destroy,
458 .targetsize = sizeof(struct ipt_clusterip_tgt_info),
459 #ifdef CONFIG_COMPAT
460 .compatsize = sizeof(struct compat_ipt_clusterip_tgt_info),
461 #endif /* CONFIG_COMPAT */
462 .me = THIS_MODULE
463 };
464
465
466 /***********************************************************************
467 * ARP MANGLING CODE
468 ***********************************************************************/
469
470 /* hardcoded for 48bit ethernet and 32bit ipv4 addresses */
471 struct arp_payload {
472 u_int8_t src_hw[ETH_ALEN];
473 __be32 src_ip;
474 u_int8_t dst_hw[ETH_ALEN];
475 __be32 dst_ip;
476 } __packed;
477
478 #ifdef DEBUG
479 static void arp_print(struct arp_payload *payload)
480 {
481 #define HBUFFERLEN 30
482 char hbuffer[HBUFFERLEN];
483 int j,k;
484
485 for (k=0, j=0; k < HBUFFERLEN-3 && j < ETH_ALEN; j++) {
486 hbuffer[k++] = hex_asc_hi(payload->src_hw[j]);
487 hbuffer[k++] = hex_asc_lo(payload->src_hw[j]);
488 hbuffer[k++]=':';
489 }
490 hbuffer[--k]='\0';
491
492 pr_debug("src %pI4@%s, dst %pI4\n",
493 &payload->src_ip, hbuffer, &payload->dst_ip);
494 }
495 #endif
496
497 static unsigned int
498 arp_mangle(const struct nf_hook_ops *ops,
499 struct sk_buff *skb,
500 const struct net_device *in,
501 const struct net_device *out,
502 int (*okfn)(struct sk_buff *))
503 {
504 struct arphdr *arp = arp_hdr(skb);
505 struct arp_payload *payload;
506 struct clusterip_config *c;
507 struct net *net = dev_net(in ? in : out);
508
509 /* we don't care about non-ethernet and non-ipv4 ARP */
510 if (arp->ar_hrd != htons(ARPHRD_ETHER) ||
511 arp->ar_pro != htons(ETH_P_IP) ||
512 arp->ar_pln != 4 || arp->ar_hln != ETH_ALEN)
513 return NF_ACCEPT;
514
515 /* we only want to mangle arp requests and replies */
516 if (arp->ar_op != htons(ARPOP_REPLY) &&
517 arp->ar_op != htons(ARPOP_REQUEST))
518 return NF_ACCEPT;
519
520 payload = (void *)(arp+1);
521
522 /* if there is no clusterip configuration for the arp reply's
523 * source ip, we don't want to mangle it */
524 c = clusterip_config_find_get(net, payload->src_ip, 0);
525 if (!c)
526 return NF_ACCEPT;
527
528 /* normally the linux kernel always replies to arp queries of
529 * addresses on different interfacs. However, in the CLUSTERIP case
530 * this wouldn't work, since we didn't subscribe the mcast group on
531 * other interfaces */
532 if (c->dev != out) {
533 pr_debug("not mangling arp reply on different "
534 "interface: cip'%s'-skb'%s'\n",
535 c->dev->name, out->name);
536 clusterip_config_put(c);
537 return NF_ACCEPT;
538 }
539
540 /* mangle reply hardware address */
541 memcpy(payload->src_hw, c->clustermac, arp->ar_hln);
542
543 #ifdef DEBUG
544 pr_debug("mangled arp reply: ");
545 arp_print(payload);
546 #endif
547
548 clusterip_config_put(c);
549
550 return NF_ACCEPT;
551 }
552
553 static struct nf_hook_ops cip_arp_ops __read_mostly = {
554 .hook = arp_mangle,
555 .pf = NFPROTO_ARP,
556 .hooknum = NF_ARP_OUT,
557 .priority = -1
558 };
559
560 /***********************************************************************
561 * PROC DIR HANDLING
562 ***********************************************************************/
563
564 #ifdef CONFIG_PROC_FS
565
566 struct clusterip_seq_position {
567 unsigned int pos; /* position */
568 unsigned int weight; /* number of bits set == size */
569 unsigned int bit; /* current bit */
570 unsigned long val; /* current value */
571 };
572
573 static void *clusterip_seq_start(struct seq_file *s, loff_t *pos)
574 {
575 struct clusterip_config *c = s->private;
576 unsigned int weight;
577 u_int32_t local_nodes;
578 struct clusterip_seq_position *idx;
579
580 /* FIXME: possible race */
581 local_nodes = c->local_nodes;
582 weight = hweight32(local_nodes);
583 if (*pos >= weight)
584 return NULL;
585
586 idx = kmalloc(sizeof(struct clusterip_seq_position), GFP_KERNEL);
587 if (!idx)
588 return ERR_PTR(-ENOMEM);
589
590 idx->pos = *pos;
591 idx->weight = weight;
592 idx->bit = ffs(local_nodes);
593 idx->val = local_nodes;
594 clear_bit(idx->bit - 1, &idx->val);
595
596 return idx;
597 }
598
599 static void *clusterip_seq_next(struct seq_file *s, void *v, loff_t *pos)
600 {
601 struct clusterip_seq_position *idx = v;
602
603 *pos = ++idx->pos;
604 if (*pos >= idx->weight) {
605 kfree(v);
606 return NULL;
607 }
608 idx->bit = ffs(idx->val);
609 clear_bit(idx->bit - 1, &idx->val);
610 return idx;
611 }
612
613 static void clusterip_seq_stop(struct seq_file *s, void *v)
614 {
615 if (!IS_ERR(v))
616 kfree(v);
617 }
618
619 static int clusterip_seq_show(struct seq_file *s, void *v)
620 {
621 struct clusterip_seq_position *idx = v;
622
623 if (idx->pos != 0)
624 seq_putc(s, ',');
625
626 seq_printf(s, "%u", idx->bit);
627
628 if (idx->pos == idx->weight - 1)
629 seq_putc(s, '\n');
630
631 return 0;
632 }
633
634 static const struct seq_operations clusterip_seq_ops = {
635 .start = clusterip_seq_start,
636 .next = clusterip_seq_next,
637 .stop = clusterip_seq_stop,
638 .show = clusterip_seq_show,
639 };
640
641 static int clusterip_proc_open(struct inode *inode, struct file *file)
642 {
643 int ret = seq_open(file, &clusterip_seq_ops);
644
645 if (!ret) {
646 struct seq_file *sf = file->private_data;
647 struct clusterip_config *c = PDE_DATA(inode);
648
649 sf->private = c;
650
651 clusterip_config_get(c);
652 }
653
654 return ret;
655 }
656
657 static int clusterip_proc_release(struct inode *inode, struct file *file)
658 {
659 struct clusterip_config *c = PDE_DATA(inode);
660 int ret;
661
662 ret = seq_release(inode, file);
663
664 if (!ret)
665 clusterip_config_put(c);
666
667 return ret;
668 }
669
670 static ssize_t clusterip_proc_write(struct file *file, const char __user *input,
671 size_t size, loff_t *ofs)
672 {
673 struct clusterip_config *c = PDE_DATA(file_inode(file));
674 #define PROC_WRITELEN 10
675 char buffer[PROC_WRITELEN+1];
676 unsigned long nodenum;
677 int rc;
678
679 if (size > PROC_WRITELEN)
680 return -EIO;
681 if (copy_from_user(buffer, input, size))
682 return -EFAULT;
683 buffer[size] = 0;
684
685 if (*buffer == '+') {
686 rc = kstrtoul(buffer+1, 10, &nodenum);
687 if (rc)
688 return rc;
689 if (clusterip_add_node(c, nodenum))
690 return -ENOMEM;
691 } else if (*buffer == '-') {
692 rc = kstrtoul(buffer+1, 10, &nodenum);
693 if (rc)
694 return rc;
695 if (clusterip_del_node(c, nodenum))
696 return -ENOENT;
697 } else
698 return -EIO;
699
700 return size;
701 }
702
703 static const struct file_operations clusterip_proc_fops = {
704 .owner = THIS_MODULE,
705 .open = clusterip_proc_open,
706 .read = seq_read,
707 .write = clusterip_proc_write,
708 .llseek = seq_lseek,
709 .release = clusterip_proc_release,
710 };
711
712 #endif /* CONFIG_PROC_FS */
713
714 static int clusterip_net_init(struct net *net)
715 {
716 struct clusterip_net *cn = net_generic(net, clusterip_net_id);
717
718 INIT_LIST_HEAD(&cn->configs);
719
720 spin_lock_init(&cn->lock);
721
722 #ifdef CONFIG_PROC_FS
723 cn->procdir = proc_mkdir("ipt_CLUSTERIP", net->proc_net);
724 if (!cn->procdir) {
725 pr_err("Unable to proc dir entry\n");
726 return -ENOMEM;
727 }
728 #endif /* CONFIG_PROC_FS */
729
730 return 0;
731 }
732
733 static void clusterip_net_exit(struct net *net)
734 {
735 #ifdef CONFIG_PROC_FS
736 struct clusterip_net *cn = net_generic(net, clusterip_net_id);
737 proc_remove(cn->procdir);
738 #endif
739 }
740
741 static struct pernet_operations clusterip_net_ops = {
742 .init = clusterip_net_init,
743 .exit = clusterip_net_exit,
744 .id = &clusterip_net_id,
745 .size = sizeof(struct clusterip_net),
746 };
747
748 static int __init clusterip_tg_init(void)
749 {
750 int ret;
751
752 ret = register_pernet_subsys(&clusterip_net_ops);
753 if (ret < 0)
754 return ret;
755
756 ret = xt_register_target(&clusterip_tg_reg);
757 if (ret < 0)
758 goto cleanup_subsys;
759
760 ret = nf_register_hook(&cip_arp_ops);
761 if (ret < 0)
762 goto cleanup_target;
763
764 pr_info("ClusterIP Version %s loaded successfully\n",
765 CLUSTERIP_VERSION);
766
767 return 0;
768
769 cleanup_target:
770 xt_unregister_target(&clusterip_tg_reg);
771 cleanup_subsys:
772 unregister_pernet_subsys(&clusterip_net_ops);
773 return ret;
774 }
775
776 static void __exit clusterip_tg_exit(void)
777 {
778 pr_info("ClusterIP Version %s unloading\n", CLUSTERIP_VERSION);
779
780 nf_unregister_hook(&cip_arp_ops);
781 xt_unregister_target(&clusterip_tg_reg);
782 unregister_pernet_subsys(&clusterip_net_ops);
783
784 /* Wait for completion of call_rcu_bh()'s (clusterip_config_rcu_free) */
785 rcu_barrier_bh();
786 }
787
788 module_init(clusterip_tg_init);
789 module_exit(clusterip_tg_exit);
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