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[NETFILTER]: convert nfmark and conntrack mark to 32bit
[linux-2.6/btrfs-unstable.git] / net / ipv4 / netfilter / ipt_CLUSTERIP.c
blob2d05cafec22120ecae24351e31f4a5f17431433a
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 #include <linux/module.h>
13 #include <linux/config.h>
14 #include <linux/proc_fs.h>
15 #include <linux/jhash.h>
16 #include <linux/skbuff.h>
17 #include <linux/ip.h>
18 #include <linux/tcp.h>
19 #include <linux/udp.h>
20 #include <linux/icmp.h>
21 #include <linux/if_arp.h>
22 #include <linux/proc_fs.h>
23 #include <linux/seq_file.h>
24
25 #include <net/checksum.h>
26
27 #include <linux/netfilter_arp.h>
28
29 #include <linux/netfilter_ipv4/ip_tables.h>
30 #include <linux/netfilter_ipv4/ipt_CLUSTERIP.h>
31 #include <linux/netfilter_ipv4/ip_conntrack.h>
32
33 #define CLUSTERIP_VERSION "0.7"
34
35 #define DEBUG_CLUSTERIP
36
37 #ifdef DEBUG_CLUSTERIP
38 #define DEBUGP printk
39 #else
40 #define DEBUGP
41 #endif
42
43 #define ASSERT_READ_LOCK(x)
44
45 MODULE_LICENSE("GPL");
46 MODULE_AUTHOR("Harald Welte <laforge@netfilter.org>");
47 MODULE_DESCRIPTION("iptables target for CLUSTERIP");
48
49 struct clusterip_config {
50 struct list_head list; /* list of all configs */
51 atomic_t refcount; /* reference count */
52
53 u_int32_t clusterip; /* the IP address */
54 u_int8_t clustermac[ETH_ALEN]; /* the MAC address */
55 struct net_device *dev; /* device */
56 u_int16_t num_total_nodes; /* total number of nodes */
57 u_int16_t num_local_nodes; /* number of local nodes */
58 u_int16_t local_nodes[CLUSTERIP_MAX_NODES]; /* node number array */
59
60 #ifdef CONFIG_PROC_FS
61 struct proc_dir_entry *pde; /* proc dir entry */
62 #endif
63 enum clusterip_hashmode hash_mode; /* which hashing mode */
64 u_int32_t hash_initval; /* hash initialization */
65 };
66
67 static LIST_HEAD(clusterip_configs);
68
69 /* clusterip_lock protects the clusterip_configs list _AND_ the configurable
70 * data within all structurses (num_local_nodes, local_nodes[]) */
71 static DEFINE_RWLOCK(clusterip_lock);
72
73 #ifdef CONFIG_PROC_FS
74 static struct file_operations clusterip_proc_fops;
75 static struct proc_dir_entry *clusterip_procdir;
76 #endif
77
78 static inline void
79 clusterip_config_get(struct clusterip_config *c) {
80 atomic_inc(&c->refcount);
81 }
82
83 static inline void
84 clusterip_config_put(struct clusterip_config *c) {
85 if (atomic_dec_and_test(&c->refcount)) {
86 write_lock_bh(&clusterip_lock);
87 list_del(&c->list);
88 write_unlock_bh(&clusterip_lock);
89 dev_mc_delete(c->dev, c->clustermac, ETH_ALEN, 0);
90 dev_put(c->dev);
91 kfree(c);
92 }
93 }
94
95
96 static struct clusterip_config *
97 __clusterip_config_find(u_int32_t clusterip)
98 {
99 struct list_head *pos;
100
101 ASSERT_READ_LOCK(&clusterip_lock);
102 list_for_each(pos, &clusterip_configs) {
103 struct clusterip_config *c = list_entry(pos,
104 struct clusterip_config, list);
105 if (c->clusterip == clusterip) {
106 return c;
107 }
108 }
109
110 return NULL;
111 }
112
113 static inline struct clusterip_config *
114 clusterip_config_find_get(u_int32_t clusterip)
115 {
116 struct clusterip_config *c;
117
118 read_lock_bh(&clusterip_lock);
119 c = __clusterip_config_find(clusterip);
120 if (!c) {
121 read_unlock_bh(&clusterip_lock);
122 return NULL;
123 }
124 atomic_inc(&c->refcount);
125 read_unlock_bh(&clusterip_lock);
126
127 return c;
128 }
129
130 static struct clusterip_config *
131 clusterip_config_init(struct ipt_clusterip_tgt_info *i, u_int32_t ip,
132 struct net_device *dev)
133 {
134 struct clusterip_config *c;
135 char buffer[16];
136
137 c = kmalloc(sizeof(*c), GFP_ATOMIC);
138 if (!c)
139 return NULL;
140
141 memset(c, 0, sizeof(*c));
142 c->dev = dev;
143 c->clusterip = ip;
144 memcpy(&c->clustermac, &i->clustermac, ETH_ALEN);
145 c->num_total_nodes = i->num_total_nodes;
146 c->num_local_nodes = i->num_local_nodes;
147 memcpy(&c->local_nodes, &i->local_nodes, sizeof(&c->local_nodes));
148 c->hash_mode = i->hash_mode;
149 c->hash_initval = i->hash_initval;
150 atomic_set(&c->refcount, 1);
151
152 #ifdef CONFIG_PROC_FS
153 /* create proc dir entry */
154 sprintf(buffer, "%u.%u.%u.%u", NIPQUAD(ip));
155 c->pde = create_proc_entry(buffer, S_IWUSR|S_IRUSR, clusterip_procdir);
156 if (!c->pde) {
157 kfree(c);
158 return NULL;
159 }
160 c->pde->proc_fops = &clusterip_proc_fops;
161 c->pde->data = c;
162 #endif
163
164 write_lock_bh(&clusterip_lock);
165 list_add(&c->list, &clusterip_configs);
166 write_unlock_bh(&clusterip_lock);
167
168 return c;
169 }
170
171 static int
172 clusterip_add_node(struct clusterip_config *c, u_int16_t nodenum)
173 {
174 int i;
175
176 write_lock_bh(&clusterip_lock);
177
178 if (c->num_local_nodes >= CLUSTERIP_MAX_NODES
179 || nodenum > CLUSTERIP_MAX_NODES) {
180 write_unlock_bh(&clusterip_lock);
181 return 1;
182 }
183
184 /* check if we alrady have this number in our array */
185 for (i = 0; i < c->num_local_nodes; i++) {
186 if (c->local_nodes[i] == nodenum) {
187 write_unlock_bh(&clusterip_lock);
188 return 1;
189 }
190 }
191
192 c->local_nodes[c->num_local_nodes++] = nodenum;
193
194 write_unlock_bh(&clusterip_lock);
195 return 0;
196 }
197
198 static int
199 clusterip_del_node(struct clusterip_config *c, u_int16_t nodenum)
200 {
201 int i;
202
203 write_lock_bh(&clusterip_lock);
204
205 if (c->num_local_nodes <= 1 || nodenum > CLUSTERIP_MAX_NODES) {
206 write_unlock_bh(&clusterip_lock);
207 return 1;
208 }
209
210 for (i = 0; i < c->num_local_nodes; i++) {
211 if (c->local_nodes[i] == nodenum) {
212 int size = sizeof(u_int16_t)*(c->num_local_nodes-(i+1));
213 memmove(&c->local_nodes[i], &c->local_nodes[i+1], size);
214 c->num_local_nodes--;
215 write_unlock_bh(&clusterip_lock);
216 return 0;
217 }
218 }
219
220 write_unlock_bh(&clusterip_lock);
221 return 1;
222 }
223
224 static inline u_int32_t
225 clusterip_hashfn(struct sk_buff *skb, struct clusterip_config *config)
226 {
227 struct iphdr *iph = skb->nh.iph;
228 unsigned long hashval;
229 u_int16_t sport, dport;
230 struct tcphdr *th;
231 struct udphdr *uh;
232 struct icmphdr *ih;
233
234 switch (iph->protocol) {
235 case IPPROTO_TCP:
236 th = (void *)iph+iph->ihl*4;
237 sport = ntohs(th->source);
238 dport = ntohs(th->dest);
239 break;
240 case IPPROTO_UDP:
241 uh = (void *)iph+iph->ihl*4;
242 sport = ntohs(uh->source);
243 dport = ntohs(uh->dest);
244 break;
245 case IPPROTO_ICMP:
246 ih = (void *)iph+iph->ihl*4;
247 sport = ntohs(ih->un.echo.id);
248 dport = (ih->type<<8)|ih->code;
249 break;
250 default:
251 if (net_ratelimit()) {
252 printk(KERN_NOTICE "CLUSTERIP: unknown protocol `%u'\n",
253 iph->protocol);
254 }
255 sport = dport = 0;
256 }
257
258 switch (config->hash_mode) {
259 case CLUSTERIP_HASHMODE_SIP:
260 hashval = jhash_1word(ntohl(iph->saddr),
261 config->hash_initval);
262 break;
263 case CLUSTERIP_HASHMODE_SIP_SPT:
264 hashval = jhash_2words(ntohl(iph->saddr), sport,
265 config->hash_initval);
266 break;
267 case CLUSTERIP_HASHMODE_SIP_SPT_DPT:
268 hashval = jhash_3words(ntohl(iph->saddr), sport, dport,
269 config->hash_initval);
270 break;
271 default:
272 /* to make gcc happy */
273 hashval = 0;
274 /* This cannot happen, unless the check function wasn't called
275 * at rule load time */
276 printk("CLUSTERIP: unknown mode `%u'\n", config->hash_mode);
277 BUG();
278 break;
279 }
280
281 /* node numbers are 1..n, not 0..n */
282 return ((hashval % config->num_total_nodes)+1);
283 }
284
285 static inline int
286 clusterip_responsible(struct clusterip_config *config, u_int32_t hash)
287 {
288 int i;
289
290 read_lock_bh(&clusterip_lock);
291
292 if (config->num_local_nodes == 0) {
293 read_unlock_bh(&clusterip_lock);
294 return 0;
295 }
296
297 for (i = 0; i < config->num_local_nodes; i++) {
298 if (config->local_nodes[i] == hash) {
299 read_unlock_bh(&clusterip_lock);
300 return 1;
301 }
302 }
303
304 read_unlock_bh(&clusterip_lock);
305
306 return 0;
307 }
308
309 /***********************************************************************
310 * IPTABLES TARGET
311 ***********************************************************************/
312
313 static unsigned int
314 target(struct sk_buff **pskb,
315 const struct net_device *in,
316 const struct net_device *out,
317 unsigned int hooknum,
318 const void *targinfo,
319 void *userinfo)
320 {
321 const struct ipt_clusterip_tgt_info *cipinfo = targinfo;
322 enum ip_conntrack_info ctinfo;
323 struct ip_conntrack *ct = ip_conntrack_get((*pskb), &ctinfo);
324 u_int32_t hash;
325
326 /* don't need to clusterip_config_get() here, since refcount
327 * is only decremented by destroy() - and ip_tables guarantees
328 * that the ->target() function isn't called after ->destroy() */
329
330 if (!ct) {
331 printk(KERN_ERR "CLUSTERIP: no conntrack!\n");
332 /* FIXME: need to drop invalid ones, since replies
333 * to outgoing connections of other nodes will be
334 * marked as INVALID */
335 return NF_DROP;
336 }
337
338 /* special case: ICMP error handling. conntrack distinguishes between
339 * error messages (RELATED) and information requests (see below) */
340 if ((*pskb)->nh.iph->protocol == IPPROTO_ICMP
341 && (ctinfo == IP_CT_RELATED
342 || ctinfo == IP_CT_RELATED+IP_CT_IS_REPLY))
343 return IPT_CONTINUE;
344
345 /* ip_conntrack_icmp guarantees us that we only have ICMP_ECHO,
346 * TIMESTAMP, INFO_REQUEST or ADDRESS type icmp packets from here
347 * on, which all have an ID field [relevant for hashing]. */
348
349 hash = clusterip_hashfn(*pskb, cipinfo->config);
350
351 switch (ctinfo) {
352 case IP_CT_NEW:
353 ct->mark = hash;
354 break;
355 case IP_CT_RELATED:
356 case IP_CT_RELATED+IP_CT_IS_REPLY:
357 /* FIXME: we don't handle expectations at the
358 * moment. they can arrive on a different node than
359 * the master connection (e.g. FTP passive mode) */
360 case IP_CT_ESTABLISHED:
361 case IP_CT_ESTABLISHED+IP_CT_IS_REPLY:
362 break;
363 default:
364 break;
365 }
366
367 #ifdef DEBUG_CLUSTERP
368 DUMP_TUPLE(&ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple);
369 #endif
370 DEBUGP("hash=%u ct_hash=%u ", hash, ct->mark);
371 if (!clusterip_responsible(cipinfo->config, hash)) {
372 DEBUGP("not responsible\n");
373 return NF_DROP;
374 }
375 DEBUGP("responsible\n");
376
377 /* despite being received via linklayer multicast, this is
378 * actually a unicast IP packet. TCP doesn't like PACKET_MULTICAST */
379 (*pskb)->pkt_type = PACKET_HOST;
380
381 return IPT_CONTINUE;
382 }
383
384 static int
385 checkentry(const char *tablename,
386 const struct ipt_entry *e,
387 void *targinfo,
388 unsigned int targinfosize,
389 unsigned int hook_mask)
390 {
391 struct ipt_clusterip_tgt_info *cipinfo = targinfo;
392
393 struct clusterip_config *config;
394
395 if (targinfosize != IPT_ALIGN(sizeof(struct ipt_clusterip_tgt_info))) {
396 printk(KERN_WARNING "CLUSTERIP: targinfosize %u != %Zu\n",
397 targinfosize,
398 IPT_ALIGN(sizeof(struct ipt_clusterip_tgt_info)));
399 return 0;
400 }
401
402 if (cipinfo->hash_mode != CLUSTERIP_HASHMODE_SIP &&
403 cipinfo->hash_mode != CLUSTERIP_HASHMODE_SIP_SPT &&
404 cipinfo->hash_mode != CLUSTERIP_HASHMODE_SIP_SPT_DPT) {
405 printk(KERN_WARNING "CLUSTERIP: unknown mode `%u'\n",
406 cipinfo->hash_mode);
407 return 0;
408
409 }
410 if (e->ip.dmsk.s_addr != 0xffffffff
411 || e->ip.dst.s_addr == 0) {
412 printk(KERN_ERR "CLUSTERIP: Please specify destination IP\n");
413 return 0;
414 }
415
416 /* FIXME: further sanity checks */
417
418 config = clusterip_config_find_get(e->ip.dst.s_addr);
419 if (!config) {
420 if (!(cipinfo->flags & CLUSTERIP_FLAG_NEW)) {
421 printk(KERN_WARNING "CLUSTERIP: no config found for %u.%u.%u.%u, need 'new'\n", NIPQUAD(e->ip.dst.s_addr));
422 return 0;
423 } else {
424 struct net_device *dev;
425
426 if (e->ip.iniface[0] == '\0') {
427 printk(KERN_WARNING "CLUSTERIP: Please specify an interface name\n");
428 return 0;
429 }
430
431 dev = dev_get_by_name(e->ip.iniface);
432 if (!dev) {
433 printk(KERN_WARNING "CLUSTERIP: no such interface %s\n", e->ip.iniface);
434 return 0;
435 }
436
437 config = clusterip_config_init(cipinfo,
438 e->ip.dst.s_addr, dev);
439 if (!config) {
440 printk(KERN_WARNING "CLUSTERIP: cannot allocate config\n");
441 dev_put(dev);
442 return 0;
443 }
444 dev_mc_add(config->dev,config->clustermac, ETH_ALEN, 0);
445 }
446 }
447
448 cipinfo->config = config;
449
450 return 1;
451 }
452
453 /* drop reference count of cluster config when rule is deleted */
454 static void destroy(void *matchinfo, unsigned int matchinfosize)
455 {
456 struct ipt_clusterip_tgt_info *cipinfo = matchinfo;
457
458 /* we first remove the proc entry and then drop the reference
459 * count. In case anyone still accesses the file, the open/close
460 * functions are also incrementing the refcount on their own */
461 #ifdef CONFIG_PROC_FS
462 remove_proc_entry(cipinfo->config->pde->name,
463 cipinfo->config->pde->parent);
464 #endif
465 clusterip_config_put(cipinfo->config);
466 }
467
468 static struct ipt_target clusterip_tgt = {
469 .name = "CLUSTERIP",
470 .target = &target,
471 .checkentry = &checkentry,
472 .destroy = &destroy,
473 .me = THIS_MODULE
474 };
475
476
477 /***********************************************************************
478 * ARP MANGLING CODE
479 ***********************************************************************/
480
481 /* hardcoded for 48bit ethernet and 32bit ipv4 addresses */
482 struct arp_payload {
483 u_int8_t src_hw[ETH_ALEN];
484 u_int32_t src_ip;
485 u_int8_t dst_hw[ETH_ALEN];
486 u_int32_t dst_ip;
487 } __attribute__ ((packed));
488
489 #ifdef CLUSTERIP_DEBUG
490 static void arp_print(struct arp_payload *payload)
491 {
492 #define HBUFFERLEN 30
493 char hbuffer[HBUFFERLEN];
494 int j,k;
495 const char hexbuf[]= "0123456789abcdef";
496
497 for (k=0, j=0; k < HBUFFERLEN-3 && j < ETH_ALEN; j++) {
498 hbuffer[k++]=hexbuf[(payload->src_hw[j]>>4)&15];
499 hbuffer[k++]=hexbuf[payload->src_hw[j]&15];
500 hbuffer[k++]=':';
501 }
502 hbuffer[--k]='\0';
503
504 printk("src %u.%u.%u.%u@%s, dst %u.%u.%u.%u\n",
505 NIPQUAD(payload->src_ip), hbuffer,
506 NIPQUAD(payload->dst_ip));
507 }
508 #endif
509
510 static unsigned int
511 arp_mangle(unsigned int hook,
512 struct sk_buff **pskb,
513 const struct net_device *in,
514 const struct net_device *out,
515 int (*okfn)(struct sk_buff *))
516 {
517 struct arphdr *arp = (*pskb)->nh.arph;
518 struct arp_payload *payload;
519 struct clusterip_config *c;
520
521 /* we don't care about non-ethernet and non-ipv4 ARP */
522 if (arp->ar_hrd != htons(ARPHRD_ETHER)
523 || arp->ar_pro != htons(ETH_P_IP)
524 || arp->ar_pln != 4 || arp->ar_hln != ETH_ALEN)
525 return NF_ACCEPT;
526
527 /* we only want to mangle arp requests and replies */
528 if (arp->ar_op != htons(ARPOP_REPLY)
529 && arp->ar_op != htons(ARPOP_REQUEST))
530 return NF_ACCEPT;
531
532 payload = (void *)(arp+1);
533
534 /* if there is no clusterip configuration for the arp reply's
535 * source ip, we don't want to mangle it */
536 c = clusterip_config_find_get(payload->src_ip);
537 if (!c)
538 return NF_ACCEPT;
539
540 /* normally the linux kernel always replies to arp queries of
541 * addresses on different interfacs. However, in the CLUSTERIP case
542 * this wouldn't work, since we didn't subscribe the mcast group on
543 * other interfaces */
544 if (c->dev != out) {
545 DEBUGP("CLUSTERIP: not mangling arp reply on different "
546 "interface: cip'%s'-skb'%s'\n", c->dev->name, out->name);
547 clusterip_config_put(c);
548 return NF_ACCEPT;
549 }
550
551 /* mangle reply hardware address */
552 memcpy(payload->src_hw, c->clustermac, arp->ar_hln);
553
554 #ifdef CLUSTERIP_DEBUG
555 DEBUGP(KERN_DEBUG "CLUSTERIP mangled arp reply: ");
556 arp_print(payload);
557 #endif
558
559 clusterip_config_put(c);
560
561 return NF_ACCEPT;
562 }
563
564 static struct nf_hook_ops cip_arp_ops = {
565 .hook = arp_mangle,
566 .pf = NF_ARP,
567 .hooknum = NF_ARP_OUT,
568 .priority = -1
569 };
570
571 /***********************************************************************
572 * PROC DIR HANDLING
573 ***********************************************************************/
574
575 #ifdef CONFIG_PROC_FS
576
577 static void *clusterip_seq_start(struct seq_file *s, loff_t *pos)
578 {
579 struct proc_dir_entry *pde = s->private;
580 struct clusterip_config *c = pde->data;
581 unsigned int *nodeidx;
582
583 read_lock_bh(&clusterip_lock);
584 if (*pos >= c->num_local_nodes)
585 return NULL;
586
587 nodeidx = kmalloc(sizeof(unsigned int), GFP_KERNEL);
588 if (!nodeidx)
589 return ERR_PTR(-ENOMEM);
590
591 *nodeidx = *pos;
592 return nodeidx;
593 }
594
595 static void *clusterip_seq_next(struct seq_file *s, void *v, loff_t *pos)
596 {
597 struct proc_dir_entry *pde = s->private;
598 struct clusterip_config *c = pde->data;
599 unsigned int *nodeidx = (unsigned int *)v;
600
601 *pos = ++(*nodeidx);
602 if (*pos >= c->num_local_nodes) {
603 kfree(v);
604 return NULL;
605 }
606 return nodeidx;
607 }
608
609 static void clusterip_seq_stop(struct seq_file *s, void *v)
610 {
611 kfree(v);
612
613 read_unlock_bh(&clusterip_lock);
614 }
615
616 static int clusterip_seq_show(struct seq_file *s, void *v)
617 {
618 struct proc_dir_entry *pde = s->private;
619 struct clusterip_config *c = pde->data;
620 unsigned int *nodeidx = (unsigned int *)v;
621
622 if (*nodeidx != 0)
623 seq_putc(s, ',');
624 seq_printf(s, "%u", c->local_nodes[*nodeidx]);
625
626 if (*nodeidx == c->num_local_nodes-1)
627 seq_putc(s, '\n');
628
629 return 0;
630 }
631
632 static struct seq_operations clusterip_seq_ops = {
633 .start = clusterip_seq_start,
634 .next = clusterip_seq_next,
635 .stop = clusterip_seq_stop,
636 .show = clusterip_seq_show,
637 };
638
639 static int clusterip_proc_open(struct inode *inode, struct file *file)
640 {
641 int ret = seq_open(file, &clusterip_seq_ops);
642
643 if (!ret) {
644 struct seq_file *sf = file->private_data;
645 struct proc_dir_entry *pde = PDE(inode);
646 struct clusterip_config *c = pde->data;
647
648 sf->private = pde;
649
650 clusterip_config_get(c);
651 }
652
653 return ret;
654 }
655
656 static int clusterip_proc_release(struct inode *inode, struct file *file)
657 {
658 struct proc_dir_entry *pde = PDE(inode);
659 struct clusterip_config *c = pde->data;
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 #define PROC_WRITELEN 10
674 char buffer[PROC_WRITELEN+1];
675 struct proc_dir_entry *pde = PDE(file->f_dentry->d_inode);
676 struct clusterip_config *c = pde->data;
677 unsigned long nodenum;
678
679 if (copy_from_user(buffer, input, PROC_WRITELEN))
680 return -EFAULT;
681
682 if (*buffer == '+') {
683 nodenum = simple_strtoul(buffer+1, NULL, 10);
684 if (clusterip_add_node(c, nodenum))
685 return -ENOMEM;
686 } else if (*buffer == '-') {
687 nodenum = simple_strtoul(buffer+1, NULL,10);
688 if (clusterip_del_node(c, nodenum))
689 return -ENOENT;
690 } else
691 return -EIO;
692
693 return size;
694 }
695
696 static struct file_operations clusterip_proc_fops = {
697 .owner = THIS_MODULE,
698 .open = clusterip_proc_open,
699 .read = seq_read,
700 .write = clusterip_proc_write,
701 .llseek = seq_lseek,
702 .release = clusterip_proc_release,
703 };
704
705 #endif /* CONFIG_PROC_FS */
706
707 static int init_or_cleanup(int fini)
708 {
709 int ret;
710
711 if (fini)
712 goto cleanup;
713
714 if (ipt_register_target(&clusterip_tgt)) {
715 ret = -EINVAL;
716 goto cleanup_none;
717 }
718
719 if (nf_register_hook(&cip_arp_ops) < 0) {
720 ret = -EINVAL;
721 goto cleanup_target;
722 }
723
724 #ifdef CONFIG_PROC_FS
725 clusterip_procdir = proc_mkdir("ipt_CLUSTERIP", proc_net);
726 if (!clusterip_procdir) {
727 printk(KERN_ERR "CLUSTERIP: Unable to proc dir entry\n");
728 ret = -ENOMEM;
729 goto cleanup_hook;
730 }
731 #endif /* CONFIG_PROC_FS */
732
733 printk(KERN_NOTICE "ClusterIP Version %s loaded successfully\n",
734 CLUSTERIP_VERSION);
735
736 return 0;
737
738 cleanup:
739 printk(KERN_NOTICE "ClusterIP Version %s unloading\n",
740 CLUSTERIP_VERSION);
741 #ifdef CONFIG_PROC_FS
742 remove_proc_entry(clusterip_procdir->name, clusterip_procdir->parent);
743 #endif
744 cleanup_hook:
745 nf_unregister_hook(&cip_arp_ops);
746 cleanup_target:
747 ipt_unregister_target(&clusterip_tgt);
748 cleanup_none:
749 return -EINVAL;
750 }
751
752 static int __init init(void)
753 {
754 return init_or_cleanup(0);
755 }
756
757 static void __exit fini(void)
758 {
759 init_or_cleanup(1);
760 }
761
762 module_init(init);
763 module_exit(fini);
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