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netfilter: xtables: make ip_tables reentrant
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / net / ipv4 / netfilter / arp_tables.c
blob07a699059390e06ab464afe5c33fa8e938c009e3
1 /*
2 * Packet matching code for ARP packets.
3 *
4 * Based heavily, if not almost entirely, upon ip_tables.c framework.
5 *
6 * Some ARP specific bits are:
7 *
8 * Copyright (C) 2002 David S. Miller (davem@redhat.com)
9 *
10 */
11 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
12 #include <linux/kernel.h>
13 #include <linux/skbuff.h>
14 #include <linux/netdevice.h>
15 #include <linux/capability.h>
16 #include <linux/if_arp.h>
17 #include <linux/kmod.h>
18 #include <linux/vmalloc.h>
19 #include <linux/proc_fs.h>
20 #include <linux/module.h>
21 #include <linux/init.h>
22 #include <linux/mutex.h>
23 #include <linux/err.h>
24 #include <net/compat.h>
25 #include <net/sock.h>
26 #include <asm/uaccess.h>
27
28 #include <linux/netfilter/x_tables.h>
29 #include <linux/netfilter_arp/arp_tables.h>
30 #include "../../netfilter/xt_repldata.h"
31
32 MODULE_LICENSE("GPL");
33 MODULE_AUTHOR("David S. Miller <davem@redhat.com>");
34 MODULE_DESCRIPTION("arptables core");
35
36 /*#define DEBUG_ARP_TABLES*/
37 /*#define DEBUG_ARP_TABLES_USER*/
38
39 #ifdef DEBUG_ARP_TABLES
40 #define dprintf(format, args...) printk(format , ## args)
41 #else
42 #define dprintf(format, args...)
43 #endif
44
45 #ifdef DEBUG_ARP_TABLES_USER
46 #define duprintf(format, args...) printk(format , ## args)
47 #else
48 #define duprintf(format, args...)
49 #endif
50
51 #ifdef CONFIG_NETFILTER_DEBUG
52 #define ARP_NF_ASSERT(x) \
53 do { \
54 if (!(x)) \
55 printk("ARP_NF_ASSERT: %s:%s:%u\n", \
56 __func__, __FILE__, __LINE__); \
57 } while(0)
58 #else
59 #define ARP_NF_ASSERT(x)
60 #endif
61
62 void *arpt_alloc_initial_table(const struct xt_table *info)
63 {
64 return xt_alloc_initial_table(arpt, ARPT);
65 }
66 EXPORT_SYMBOL_GPL(arpt_alloc_initial_table);
67
68 static inline int arp_devaddr_compare(const struct arpt_devaddr_info *ap,
69 const char *hdr_addr, int len)
70 {
71 int i, ret;
72
73 if (len > ARPT_DEV_ADDR_LEN_MAX)
74 len = ARPT_DEV_ADDR_LEN_MAX;
75
76 ret = 0;
77 for (i = 0; i < len; i++)
78 ret |= (hdr_addr[i] ^ ap->addr[i]) & ap->mask[i];
79
80 return (ret != 0);
81 }
82
83 /*
84 * Unfortunatly, _b and _mask are not aligned to an int (or long int)
85 * Some arches dont care, unrolling the loop is a win on them.
86 * For other arches, we only have a 16bit alignement.
87 */
88 static unsigned long ifname_compare(const char *_a, const char *_b, const char *_mask)
89 {
90 #ifdef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS
91 unsigned long ret = ifname_compare_aligned(_a, _b, _mask);
92 #else
93 unsigned long ret = 0;
94 const u16 *a = (const u16 *)_a;
95 const u16 *b = (const u16 *)_b;
96 const u16 *mask = (const u16 *)_mask;
97 int i;
98
99 for (i = 0; i < IFNAMSIZ/sizeof(u16); i++)
100 ret |= (a[i] ^ b[i]) & mask[i];
101 #endif
102 return ret;
103 }
104
105 /* Returns whether packet matches rule or not. */
106 static inline int arp_packet_match(const struct arphdr *arphdr,
107 struct net_device *dev,
108 const char *indev,
109 const char *outdev,
110 const struct arpt_arp *arpinfo)
111 {
112 const char *arpptr = (char *)(arphdr + 1);
113 const char *src_devaddr, *tgt_devaddr;
114 __be32 src_ipaddr, tgt_ipaddr;
115 long ret;
116
117 #define FWINV(bool, invflg) ((bool) ^ !!(arpinfo->invflags & (invflg)))
118
119 if (FWINV((arphdr->ar_op & arpinfo->arpop_mask) != arpinfo->arpop,
120 ARPT_INV_ARPOP)) {
121 dprintf("ARP operation field mismatch.\n");
122 dprintf("ar_op: %04x info->arpop: %04x info->arpop_mask: %04x\n",
123 arphdr->ar_op, arpinfo->arpop, arpinfo->arpop_mask);
124 return 0;
125 }
126
127 if (FWINV((arphdr->ar_hrd & arpinfo->arhrd_mask) != arpinfo->arhrd,
128 ARPT_INV_ARPHRD)) {
129 dprintf("ARP hardware address format mismatch.\n");
130 dprintf("ar_hrd: %04x info->arhrd: %04x info->arhrd_mask: %04x\n",
131 arphdr->ar_hrd, arpinfo->arhrd, arpinfo->arhrd_mask);
132 return 0;
133 }
134
135 if (FWINV((arphdr->ar_pro & arpinfo->arpro_mask) != arpinfo->arpro,
136 ARPT_INV_ARPPRO)) {
137 dprintf("ARP protocol address format mismatch.\n");
138 dprintf("ar_pro: %04x info->arpro: %04x info->arpro_mask: %04x\n",
139 arphdr->ar_pro, arpinfo->arpro, arpinfo->arpro_mask);
140 return 0;
141 }
142
143 if (FWINV((arphdr->ar_hln & arpinfo->arhln_mask) != arpinfo->arhln,
144 ARPT_INV_ARPHLN)) {
145 dprintf("ARP hardware address length mismatch.\n");
146 dprintf("ar_hln: %02x info->arhln: %02x info->arhln_mask: %02x\n",
147 arphdr->ar_hln, arpinfo->arhln, arpinfo->arhln_mask);
148 return 0;
149 }
150
151 src_devaddr = arpptr;
152 arpptr += dev->addr_len;
153 memcpy(&src_ipaddr, arpptr, sizeof(u32));
154 arpptr += sizeof(u32);
155 tgt_devaddr = arpptr;
156 arpptr += dev->addr_len;
157 memcpy(&tgt_ipaddr, arpptr, sizeof(u32));
158
159 if (FWINV(arp_devaddr_compare(&arpinfo->src_devaddr, src_devaddr, dev->addr_len),
160 ARPT_INV_SRCDEVADDR) ||
161 FWINV(arp_devaddr_compare(&arpinfo->tgt_devaddr, tgt_devaddr, dev->addr_len),
162 ARPT_INV_TGTDEVADDR)) {
163 dprintf("Source or target device address mismatch.\n");
164
165 return 0;
166 }
167
168 if (FWINV((src_ipaddr & arpinfo->smsk.s_addr) != arpinfo->src.s_addr,
169 ARPT_INV_SRCIP) ||
170 FWINV(((tgt_ipaddr & arpinfo->tmsk.s_addr) != arpinfo->tgt.s_addr),
171 ARPT_INV_TGTIP)) {
172 dprintf("Source or target IP address mismatch.\n");
173
174 dprintf("SRC: %pI4. Mask: %pI4. Target: %pI4.%s\n",
175 &src_ipaddr,
176 &arpinfo->smsk.s_addr,
177 &arpinfo->src.s_addr,
178 arpinfo->invflags & ARPT_INV_SRCIP ? " (INV)" : "");
179 dprintf("TGT: %pI4 Mask: %pI4 Target: %pI4.%s\n",
180 &tgt_ipaddr,
181 &arpinfo->tmsk.s_addr,
182 &arpinfo->tgt.s_addr,
183 arpinfo->invflags & ARPT_INV_TGTIP ? " (INV)" : "");
184 return 0;
185 }
186
187 /* Look for ifname matches. */
188 ret = ifname_compare(indev, arpinfo->iniface, arpinfo->iniface_mask);
189
190 if (FWINV(ret != 0, ARPT_INV_VIA_IN)) {
191 dprintf("VIA in mismatch (%s vs %s).%s\n",
192 indev, arpinfo->iniface,
193 arpinfo->invflags&ARPT_INV_VIA_IN ?" (INV)":"");
194 return 0;
195 }
196
197 ret = ifname_compare(outdev, arpinfo->outiface, arpinfo->outiface_mask);
198
199 if (FWINV(ret != 0, ARPT_INV_VIA_OUT)) {
200 dprintf("VIA out mismatch (%s vs %s).%s\n",
201 outdev, arpinfo->outiface,
202 arpinfo->invflags&ARPT_INV_VIA_OUT ?" (INV)":"");
203 return 0;
204 }
205
206 return 1;
207 #undef FWINV
208 }
209
210 static inline int arp_checkentry(const struct arpt_arp *arp)
211 {
212 if (arp->flags & ~ARPT_F_MASK) {
213 duprintf("Unknown flag bits set: %08X\n",
214 arp->flags & ~ARPT_F_MASK);
215 return 0;
216 }
217 if (arp->invflags & ~ARPT_INV_MASK) {
218 duprintf("Unknown invflag bits set: %08X\n",
219 arp->invflags & ~ARPT_INV_MASK);
220 return 0;
221 }
222
223 return 1;
224 }
225
226 static unsigned int
227 arpt_error(struct sk_buff *skb, const struct xt_target_param *par)
228 {
229 if (net_ratelimit())
230 printk("arp_tables: error: '%s'\n",
231 (const char *)par->targinfo);
232
233 return NF_DROP;
234 }
235
236 static inline const struct arpt_entry_target *
237 arpt_get_target_c(const struct arpt_entry *e)
238 {
239 return arpt_get_target((struct arpt_entry *)e);
240 }
241
242 static inline struct arpt_entry *
243 get_entry(const void *base, unsigned int offset)
244 {
245 return (struct arpt_entry *)(base + offset);
246 }
247
248 static inline __pure
249 struct arpt_entry *arpt_next_entry(const struct arpt_entry *entry)
250 {
251 return (void *)entry + entry->next_offset;
252 }
253
254 unsigned int arpt_do_table(struct sk_buff *skb,
255 unsigned int hook,
256 const struct net_device *in,
257 const struct net_device *out,
258 struct xt_table *table)
259 {
260 static const char nulldevname[IFNAMSIZ] __attribute__((aligned(sizeof(long))));
261 unsigned int verdict = NF_DROP;
262 const struct arphdr *arp;
263 bool hotdrop = false;
264 struct arpt_entry *e, *back;
265 const char *indev, *outdev;
266 void *table_base;
267 const struct xt_table_info *private;
268 struct xt_target_param tgpar;
269
270 if (!pskb_may_pull(skb, arp_hdr_len(skb->dev)))
271 return NF_DROP;
272
273 indev = in ? in->name : nulldevname;
274 outdev = out ? out->name : nulldevname;
275
276 xt_info_rdlock_bh();
277 private = table->private;
278 table_base = private->entries[smp_processor_id()];
279
280 e = get_entry(table_base, private->hook_entry[hook]);
281 back = get_entry(table_base, private->underflow[hook]);
282
283 tgpar.in = in;
284 tgpar.out = out;
285 tgpar.hooknum = hook;
286 tgpar.family = NFPROTO_ARP;
287
288 arp = arp_hdr(skb);
289 do {
290 const struct arpt_entry_target *t;
291 int hdr_len;
292
293 if (!arp_packet_match(arp, skb->dev, indev, outdev, &e->arp)) {
294 e = arpt_next_entry(e);
295 continue;
296 }
297
298 hdr_len = sizeof(*arp) + (2 * sizeof(struct in_addr)) +
299 (2 * skb->dev->addr_len);
300 ADD_COUNTER(e->counters, hdr_len, 1);
301
302 t = arpt_get_target_c(e);
303
304 /* Standard target? */
305 if (!t->u.kernel.target->target) {
306 int v;
307
308 v = ((struct arpt_standard_target *)t)->verdict;
309 if (v < 0) {
310 /* Pop from stack? */
311 if (v != ARPT_RETURN) {
312 verdict = (unsigned)(-v) - 1;
313 break;
314 }
315 e = back;
316 back = get_entry(table_base, back->comefrom);
317 continue;
318 }
319 if (table_base + v
320 != arpt_next_entry(e)) {
321 /* Save old back ptr in next entry */
322 struct arpt_entry *next = arpt_next_entry(e);
323 next->comefrom = (void *)back - table_base;
324
325 /* set back pointer to next entry */
326 back = next;
327 }
328
329 e = get_entry(table_base, v);
330 continue;
331 }
332
333 /* Targets which reenter must return
334 * abs. verdicts
335 */
336 tgpar.target = t->u.kernel.target;
337 tgpar.targinfo = t->data;
338 verdict = t->u.kernel.target->target(skb, &tgpar);
339
340 /* Target might have changed stuff. */
341 arp = arp_hdr(skb);
342
343 if (verdict == ARPT_CONTINUE)
344 e = arpt_next_entry(e);
345 else
346 /* Verdict */
347 break;
348 } while (!hotdrop);
349 xt_info_rdunlock_bh();
350
351 if (hotdrop)
352 return NF_DROP;
353 else
354 return verdict;
355 }
356
357 /* All zeroes == unconditional rule. */
358 static inline bool unconditional(const struct arpt_arp *arp)
359 {
360 static const struct arpt_arp uncond;
361
362 return memcmp(arp, &uncond, sizeof(uncond)) == 0;
363 }
364
365 /* Figures out from what hook each rule can be called: returns 0 if
366 * there are loops. Puts hook bitmask in comefrom.
367 */
368 static int mark_source_chains(const struct xt_table_info *newinfo,
369 unsigned int valid_hooks, void *entry0)
370 {
371 unsigned int hook;
372
373 /* No recursion; use packet counter to save back ptrs (reset
374 * to 0 as we leave), and comefrom to save source hook bitmask.
375 */
376 for (hook = 0; hook < NF_ARP_NUMHOOKS; hook++) {
377 unsigned int pos = newinfo->hook_entry[hook];
378 struct arpt_entry *e
379 = (struct arpt_entry *)(entry0 + pos);
380
381 if (!(valid_hooks & (1 << hook)))
382 continue;
383
384 /* Set initial back pointer. */
385 e->counters.pcnt = pos;
386
387 for (;;) {
388 const struct arpt_standard_target *t
389 = (void *)arpt_get_target_c(e);
390 int visited = e->comefrom & (1 << hook);
391
392 if (e->comefrom & (1 << NF_ARP_NUMHOOKS)) {
393 printk("arptables: loop hook %u pos %u %08X.\n",
394 hook, pos, e->comefrom);
395 return 0;
396 }
397 e->comefrom
398 |= ((1 << hook) | (1 << NF_ARP_NUMHOOKS));
399
400 /* Unconditional return/END. */
401 if ((e->target_offset == sizeof(struct arpt_entry) &&
402 (strcmp(t->target.u.user.name,
403 ARPT_STANDARD_TARGET) == 0) &&
404 t->verdict < 0 && unconditional(&e->arp)) ||
405 visited) {
406 unsigned int oldpos, size;
407
408 if ((strcmp(t->target.u.user.name,
409 ARPT_STANDARD_TARGET) == 0) &&
410 t->verdict < -NF_MAX_VERDICT - 1) {
411 duprintf("mark_source_chains: bad "
412 "negative verdict (%i)\n",
413 t->verdict);
414 return 0;
415 }
416
417 /* Return: backtrack through the last
418 * big jump.
419 */
420 do {
421 e->comefrom ^= (1<<NF_ARP_NUMHOOKS);
422 oldpos = pos;
423 pos = e->counters.pcnt;
424 e->counters.pcnt = 0;
425
426 /* We're at the start. */
427 if (pos == oldpos)
428 goto next;
429
430 e = (struct arpt_entry *)
431 (entry0 + pos);
432 } while (oldpos == pos + e->next_offset);
433
434 /* Move along one */
435 size = e->next_offset;
436 e = (struct arpt_entry *)
437 (entry0 + pos + size);
438 e->counters.pcnt = pos;
439 pos += size;
440 } else {
441 int newpos = t->verdict;
442
443 if (strcmp(t->target.u.user.name,
444 ARPT_STANDARD_TARGET) == 0 &&
445 newpos >= 0) {
446 if (newpos > newinfo->size -
447 sizeof(struct arpt_entry)) {
448 duprintf("mark_source_chains: "
449 "bad verdict (%i)\n",
450 newpos);
451 return 0;
452 }
453
454 /* This a jump; chase it. */
455 duprintf("Jump rule %u -> %u\n",
456 pos, newpos);
457 } else {
458 /* ... this is a fallthru */
459 newpos = pos + e->next_offset;
460 }
461 e = (struct arpt_entry *)
462 (entry0 + newpos);
463 e->counters.pcnt = pos;
464 pos = newpos;
465 }
466 }
467 next:
468 duprintf("Finished chain %u\n", hook);
469 }
470 return 1;
471 }
472
473 static inline int check_entry(const struct arpt_entry *e, const char *name)
474 {
475 const struct arpt_entry_target *t;
476
477 if (!arp_checkentry(&e->arp)) {
478 duprintf("arp_tables: arp check failed %p %s.\n", e, name);
479 return -EINVAL;
480 }
481
482 if (e->target_offset + sizeof(struct arpt_entry_target) > e->next_offset)
483 return -EINVAL;
484
485 t = arpt_get_target_c(e);
486 if (e->target_offset + t->u.target_size > e->next_offset)
487 return -EINVAL;
488
489 return 0;
490 }
491
492 static inline int check_target(struct arpt_entry *e, const char *name)
493 {
494 struct arpt_entry_target *t = arpt_get_target(e);
495 int ret;
496 struct xt_tgchk_param par = {
497 .table = name,
498 .entryinfo = e,
499 .target = t->u.kernel.target,
500 .targinfo = t->data,
501 .hook_mask = e->comefrom,
502 .family = NFPROTO_ARP,
503 };
504
505 ret = xt_check_target(&par, t->u.target_size - sizeof(*t), 0, false);
506 if (ret < 0) {
507 duprintf("arp_tables: check failed for `%s'.\n",
508 t->u.kernel.target->name);
509 return ret;
510 }
511 return 0;
512 }
513
514 static inline int
515 find_check_entry(struct arpt_entry *e, const char *name, unsigned int size)
516 {
517 struct arpt_entry_target *t;
518 struct xt_target *target;
519 int ret;
520
521 ret = check_entry(e, name);
522 if (ret)
523 return ret;
524
525 t = arpt_get_target(e);
526 target = xt_request_find_target(NFPROTO_ARP, t->u.user.name,
527 t->u.user.revision);
528 if (IS_ERR(target)) {
529 duprintf("find_check_entry: `%s' not found\n", t->u.user.name);
530 ret = PTR_ERR(target);
531 goto out;
532 }
533 t->u.kernel.target = target;
534
535 ret = check_target(e, name);
536 if (ret)
537 goto err;
538 return 0;
539 err:
540 module_put(t->u.kernel.target->me);
541 out:
542 return ret;
543 }
544
545 static bool check_underflow(const struct arpt_entry *e)
546 {
547 const struct arpt_entry_target *t;
548 unsigned int verdict;
549
550 if (!unconditional(&e->arp))
551 return false;
552 t = arpt_get_target_c(e);
553 if (strcmp(t->u.user.name, XT_STANDARD_TARGET) != 0)
554 return false;
555 verdict = ((struct arpt_standard_target *)t)->verdict;
556 verdict = -verdict - 1;
557 return verdict == NF_DROP || verdict == NF_ACCEPT;
558 }
559
560 static inline int check_entry_size_and_hooks(struct arpt_entry *e,
561 struct xt_table_info *newinfo,
562 const unsigned char *base,
563 const unsigned char *limit,
564 const unsigned int *hook_entries,
565 const unsigned int *underflows,
566 unsigned int valid_hooks)
567 {
568 unsigned int h;
569
570 if ((unsigned long)e % __alignof__(struct arpt_entry) != 0 ||
571 (unsigned char *)e + sizeof(struct arpt_entry) >= limit) {
572 duprintf("Bad offset %p\n", e);
573 return -EINVAL;
574 }
575
576 if (e->next_offset
577 < sizeof(struct arpt_entry) + sizeof(struct arpt_entry_target)) {
578 duprintf("checking: element %p size %u\n",
579 e, e->next_offset);
580 return -EINVAL;
581 }
582
583 /* Check hooks & underflows */
584 for (h = 0; h < NF_ARP_NUMHOOKS; h++) {
585 if (!(valid_hooks & (1 << h)))
586 continue;
587 if ((unsigned char *)e - base == hook_entries[h])
588 newinfo->hook_entry[h] = hook_entries[h];
589 if ((unsigned char *)e - base == underflows[h]) {
590 if (!check_underflow(e)) {
591 pr_err("Underflows must be unconditional and "
592 "use the STANDARD target with "
593 "ACCEPT/DROP\n");
594 return -EINVAL;
595 }
596 newinfo->underflow[h] = underflows[h];
597 }
598 }
599
600 /* Clear counters and comefrom */
601 e->counters = ((struct xt_counters) { 0, 0 });
602 e->comefrom = 0;
603 return 0;
604 }
605
606 static inline void cleanup_entry(struct arpt_entry *e)
607 {
608 struct xt_tgdtor_param par;
609 struct arpt_entry_target *t;
610
611 t = arpt_get_target(e);
612 par.target = t->u.kernel.target;
613 par.targinfo = t->data;
614 par.family = NFPROTO_ARP;
615 if (par.target->destroy != NULL)
616 par.target->destroy(&par);
617 module_put(par.target->me);
618 }
619
620 /* Checks and translates the user-supplied table segment (held in
621 * newinfo).
622 */
623 static int translate_table(struct xt_table_info *newinfo, void *entry0,
624 const struct arpt_replace *repl)
625 {
626 struct arpt_entry *iter;
627 unsigned int i;
628 int ret = 0;
629
630 newinfo->size = repl->size;
631 newinfo->number = repl->num_entries;
632
633 /* Init all hooks to impossible value. */
634 for (i = 0; i < NF_ARP_NUMHOOKS; i++) {
635 newinfo->hook_entry[i] = 0xFFFFFFFF;
636 newinfo->underflow[i] = 0xFFFFFFFF;
637 }
638
639 duprintf("translate_table: size %u\n", newinfo->size);
640 i = 0;
641
642 /* Walk through entries, checking offsets. */
643 xt_entry_foreach(iter, entry0, newinfo->size) {
644 ret = check_entry_size_and_hooks(iter, newinfo, entry0,
645 entry0 + repl->size,
646 repl->hook_entry,
647 repl->underflow,
648 repl->valid_hooks);
649 if (ret != 0)
650 break;
651 ++i;
652 if (strcmp(arpt_get_target(iter)->u.user.name,
653 XT_ERROR_TARGET) == 0)
654 ++newinfo->stacksize;
655 }
656 duprintf("translate_table: ARPT_ENTRY_ITERATE gives %d\n", ret);
657 if (ret != 0)
658 return ret;
659
660 if (i != repl->num_entries) {
661 duprintf("translate_table: %u not %u entries\n",
662 i, repl->num_entries);
663 return -EINVAL;
664 }
665
666 /* Check hooks all assigned */
667 for (i = 0; i < NF_ARP_NUMHOOKS; i++) {
668 /* Only hooks which are valid */
669 if (!(repl->valid_hooks & (1 << i)))
670 continue;
671 if (newinfo->hook_entry[i] == 0xFFFFFFFF) {
672 duprintf("Invalid hook entry %u %u\n",
673 i, repl->hook_entry[i]);
674 return -EINVAL;
675 }
676 if (newinfo->underflow[i] == 0xFFFFFFFF) {
677 duprintf("Invalid underflow %u %u\n",
678 i, repl->underflow[i]);
679 return -EINVAL;
680 }
681 }
682
683 if (!mark_source_chains(newinfo, repl->valid_hooks, entry0)) {
684 duprintf("Looping hook\n");
685 return -ELOOP;
686 }
687
688 /* Finally, each sanity check must pass */
689 i = 0;
690 xt_entry_foreach(iter, entry0, newinfo->size) {
691 ret = find_check_entry(iter, repl->name, repl->size);
692 if (ret != 0)
693 break;
694 ++i;
695 }
696
697 if (ret != 0) {
698 xt_entry_foreach(iter, entry0, newinfo->size) {
699 if (i-- == 0)
700 break;
701 cleanup_entry(iter);
702 }
703 return ret;
704 }
705
706 /* And one copy for every other CPU */
707 for_each_possible_cpu(i) {
708 if (newinfo->entries[i] && newinfo->entries[i] != entry0)
709 memcpy(newinfo->entries[i], entry0, newinfo->size);
710 }
711
712 return ret;
713 }
714
715 static void get_counters(const struct xt_table_info *t,
716 struct xt_counters counters[])
717 {
718 struct arpt_entry *iter;
719 unsigned int cpu;
720 unsigned int i;
721 unsigned int curcpu;
722
723 /* Instead of clearing (by a previous call to memset())
724 * the counters and using adds, we set the counters
725 * with data used by 'current' CPU
726 *
727 * Bottom half has to be disabled to prevent deadlock
728 * if new softirq were to run and call ipt_do_table
729 */
730 local_bh_disable();
731 curcpu = smp_processor_id();
732
733 i = 0;
734 xt_entry_foreach(iter, t->entries[curcpu], t->size) {
735 SET_COUNTER(counters[i], iter->counters.bcnt,
736 iter->counters.pcnt);
737 ++i;
738 }
739
740 for_each_possible_cpu(cpu) {
741 if (cpu == curcpu)
742 continue;
743 i = 0;
744 xt_info_wrlock(cpu);
745 xt_entry_foreach(iter, t->entries[cpu], t->size) {
746 ADD_COUNTER(counters[i], iter->counters.bcnt,
747 iter->counters.pcnt);
748 ++i;
749 }
750 xt_info_wrunlock(cpu);
751 }
752 local_bh_enable();
753 }
754
755 static struct xt_counters *alloc_counters(const struct xt_table *table)
756 {
757 unsigned int countersize;
758 struct xt_counters *counters;
759 const struct xt_table_info *private = table->private;
760
761 /* We need atomic snapshot of counters: rest doesn't change
762 * (other than comefrom, which userspace doesn't care
763 * about).
764 */
765 countersize = sizeof(struct xt_counters) * private->number;
766 counters = vmalloc_node(countersize, numa_node_id());
767
768 if (counters == NULL)
769 return ERR_PTR(-ENOMEM);
770
771 get_counters(private, counters);
772
773 return counters;
774 }
775
776 static int copy_entries_to_user(unsigned int total_size,
777 const struct xt_table *table,
778 void __user *userptr)
779 {
780 unsigned int off, num;
781 const struct arpt_entry *e;
782 struct xt_counters *counters;
783 struct xt_table_info *private = table->private;
784 int ret = 0;
785 void *loc_cpu_entry;
786
787 counters = alloc_counters(table);
788 if (IS_ERR(counters))
789 return PTR_ERR(counters);
790
791 loc_cpu_entry = private->entries[raw_smp_processor_id()];
792 /* ... then copy entire thing ... */
793 if (copy_to_user(userptr, loc_cpu_entry, total_size) != 0) {
794 ret = -EFAULT;
795 goto free_counters;
796 }
797
798 /* FIXME: use iterator macros --RR */
799 /* ... then go back and fix counters and names */
800 for (off = 0, num = 0; off < total_size; off += e->next_offset, num++){
801 const struct arpt_entry_target *t;
802
803 e = (struct arpt_entry *)(loc_cpu_entry + off);
804 if (copy_to_user(userptr + off
805 + offsetof(struct arpt_entry, counters),
806 &counters[num],
807 sizeof(counters[num])) != 0) {
808 ret = -EFAULT;
809 goto free_counters;
810 }
811
812 t = arpt_get_target_c(e);
813 if (copy_to_user(userptr + off + e->target_offset
814 + offsetof(struct arpt_entry_target,
815 u.user.name),
816 t->u.kernel.target->name,
817 strlen(t->u.kernel.target->name)+1) != 0) {
818 ret = -EFAULT;
819 goto free_counters;
820 }
821 }
822
823 free_counters:
824 vfree(counters);
825 return ret;
826 }
827
828 #ifdef CONFIG_COMPAT
829 static void compat_standard_from_user(void *dst, const void *src)
830 {
831 int v = *(compat_int_t *)src;
832
833 if (v > 0)
834 v += xt_compat_calc_jump(NFPROTO_ARP, v);
835 memcpy(dst, &v, sizeof(v));
836 }
837
838 static int compat_standard_to_user(void __user *dst, const void *src)
839 {
840 compat_int_t cv = *(int *)src;
841
842 if (cv > 0)
843 cv -= xt_compat_calc_jump(NFPROTO_ARP, cv);
844 return copy_to_user(dst, &cv, sizeof(cv)) ? -EFAULT : 0;
845 }
846
847 static int compat_calc_entry(const struct arpt_entry *e,
848 const struct xt_table_info *info,
849 const void *base, struct xt_table_info *newinfo)
850 {
851 const struct arpt_entry_target *t;
852 unsigned int entry_offset;
853 int off, i, ret;
854
855 off = sizeof(struct arpt_entry) - sizeof(struct compat_arpt_entry);
856 entry_offset = (void *)e - base;
857
858 t = arpt_get_target_c(e);
859 off += xt_compat_target_offset(t->u.kernel.target);
860 newinfo->size -= off;
861 ret = xt_compat_add_offset(NFPROTO_ARP, entry_offset, off);
862 if (ret)
863 return ret;
864
865 for (i = 0; i < NF_ARP_NUMHOOKS; i++) {
866 if (info->hook_entry[i] &&
867 (e < (struct arpt_entry *)(base + info->hook_entry[i])))
868 newinfo->hook_entry[i] -= off;
869 if (info->underflow[i] &&
870 (e < (struct arpt_entry *)(base + info->underflow[i])))
871 newinfo->underflow[i] -= off;
872 }
873 return 0;
874 }
875
876 static int compat_table_info(const struct xt_table_info *info,
877 struct xt_table_info *newinfo)
878 {
879 struct arpt_entry *iter;
880 void *loc_cpu_entry;
881 int ret;
882
883 if (!newinfo || !info)
884 return -EINVAL;
885
886 /* we dont care about newinfo->entries[] */
887 memcpy(newinfo, info, offsetof(struct xt_table_info, entries));
888 newinfo->initial_entries = 0;
889 loc_cpu_entry = info->entries[raw_smp_processor_id()];
890 xt_entry_foreach(iter, loc_cpu_entry, info->size) {
891 ret = compat_calc_entry(iter, info, loc_cpu_entry, newinfo);
892 if (ret != 0)
893 return ret;
894 }
895 return 0;
896 }
897 #endif
898
899 static int get_info(struct net *net, void __user *user,
900 const int *len, int compat)
901 {
902 char name[ARPT_TABLE_MAXNAMELEN];
903 struct xt_table *t;
904 int ret;
905
906 if (*len != sizeof(struct arpt_getinfo)) {
907 duprintf("length %u != %Zu\n", *len,
908 sizeof(struct arpt_getinfo));
909 return -EINVAL;
910 }
911
912 if (copy_from_user(name, user, sizeof(name)) != 0)
913 return -EFAULT;
914
915 name[ARPT_TABLE_MAXNAMELEN-1] = '\0';
916 #ifdef CONFIG_COMPAT
917 if (compat)
918 xt_compat_lock(NFPROTO_ARP);
919 #endif
920 t = try_then_request_module(xt_find_table_lock(net, NFPROTO_ARP, name),
921 "arptable_%s", name);
922 if (t && !IS_ERR(t)) {
923 struct arpt_getinfo info;
924 const struct xt_table_info *private = t->private;
925 #ifdef CONFIG_COMPAT
926 struct xt_table_info tmp;
927
928 if (compat) {
929 ret = compat_table_info(private, &tmp);
930 xt_compat_flush_offsets(NFPROTO_ARP);
931 private = &tmp;
932 }
933 #endif
934 info.valid_hooks = t->valid_hooks;
935 memcpy(info.hook_entry, private->hook_entry,
936 sizeof(info.hook_entry));
937 memcpy(info.underflow, private->underflow,
938 sizeof(info.underflow));
939 info.num_entries = private->number;
940 info.size = private->size;
941 strcpy(info.name, name);
942
943 if (copy_to_user(user, &info, *len) != 0)
944 ret = -EFAULT;
945 else
946 ret = 0;
947 xt_table_unlock(t);
948 module_put(t->me);
949 } else
950 ret = t ? PTR_ERR(t) : -ENOENT;
951 #ifdef CONFIG_COMPAT
952 if (compat)
953 xt_compat_unlock(NFPROTO_ARP);
954 #endif
955 return ret;
956 }
957
958 static int get_entries(struct net *net, struct arpt_get_entries __user *uptr,
959 const int *len)
960 {
961 int ret;
962 struct arpt_get_entries get;
963 struct xt_table *t;
964
965 if (*len < sizeof(get)) {
966 duprintf("get_entries: %u < %Zu\n", *len, sizeof(get));
967 return -EINVAL;
968 }
969 if (copy_from_user(&get, uptr, sizeof(get)) != 0)
970 return -EFAULT;
971 if (*len != sizeof(struct arpt_get_entries) + get.size) {
972 duprintf("get_entries: %u != %Zu\n", *len,
973 sizeof(struct arpt_get_entries) + get.size);
974 return -EINVAL;
975 }
976
977 t = xt_find_table_lock(net, NFPROTO_ARP, get.name);
978 if (t && !IS_ERR(t)) {
979 const struct xt_table_info *private = t->private;
980
981 duprintf("t->private->number = %u\n",
982 private->number);
983 if (get.size == private->size)
984 ret = copy_entries_to_user(private->size,
985 t, uptr->entrytable);
986 else {
987 duprintf("get_entries: I've got %u not %u!\n",
988 private->size, get.size);
989 ret = -EAGAIN;
990 }
991 module_put(t->me);
992 xt_table_unlock(t);
993 } else
994 ret = t ? PTR_ERR(t) : -ENOENT;
995
996 return ret;
997 }
998
999 static int __do_replace(struct net *net, const char *name,
1000 unsigned int valid_hooks,
1001 struct xt_table_info *newinfo,
1002 unsigned int num_counters,
1003 void __user *counters_ptr)
1004 {
1005 int ret;
1006 struct xt_table *t;
1007 struct xt_table_info *oldinfo;
1008 struct xt_counters *counters;
1009 void *loc_cpu_old_entry;
1010 struct arpt_entry *iter;
1011
1012 ret = 0;
1013 counters = vmalloc_node(num_counters * sizeof(struct xt_counters),
1014 numa_node_id());
1015 if (!counters) {
1016 ret = -ENOMEM;
1017 goto out;
1018 }
1019
1020 t = try_then_request_module(xt_find_table_lock(net, NFPROTO_ARP, name),
1021 "arptable_%s", name);
1022 if (!t || IS_ERR(t)) {
1023 ret = t ? PTR_ERR(t) : -ENOENT;
1024 goto free_newinfo_counters_untrans;
1025 }
1026
1027 /* You lied! */
1028 if (valid_hooks != t->valid_hooks) {
1029 duprintf("Valid hook crap: %08X vs %08X\n",
1030 valid_hooks, t->valid_hooks);
1031 ret = -EINVAL;
1032 goto put_module;
1033 }
1034
1035 oldinfo = xt_replace_table(t, num_counters, newinfo, &ret);
1036 if (!oldinfo)
1037 goto put_module;
1038
1039 /* Update module usage count based on number of rules */
1040 duprintf("do_replace: oldnum=%u, initnum=%u, newnum=%u\n",
1041 oldinfo->number, oldinfo->initial_entries, newinfo->number);
1042 if ((oldinfo->number > oldinfo->initial_entries) ||
1043 (newinfo->number <= oldinfo->initial_entries))
1044 module_put(t->me);
1045 if ((oldinfo->number > oldinfo->initial_entries) &&
1046 (newinfo->number <= oldinfo->initial_entries))
1047 module_put(t->me);
1048
1049 /* Get the old counters, and synchronize with replace */
1050 get_counters(oldinfo, counters);
1051
1052 /* Decrease module usage counts and free resource */
1053 loc_cpu_old_entry = oldinfo->entries[raw_smp_processor_id()];
1054 xt_entry_foreach(iter, loc_cpu_old_entry, oldinfo->size)
1055 cleanup_entry(iter);
1056
1057 xt_free_table_info(oldinfo);
1058 if (copy_to_user(counters_ptr, counters,
1059 sizeof(struct xt_counters) * num_counters) != 0)
1060 ret = -EFAULT;
1061 vfree(counters);
1062 xt_table_unlock(t);
1063 return ret;
1064
1065 put_module:
1066 module_put(t->me);
1067 xt_table_unlock(t);
1068 free_newinfo_counters_untrans:
1069 vfree(counters);
1070 out:
1071 return ret;
1072 }
1073
1074 static int do_replace(struct net *net, const void __user *user,
1075 unsigned int len)
1076 {
1077 int ret;
1078 struct arpt_replace tmp;
1079 struct xt_table_info *newinfo;
1080 void *loc_cpu_entry;
1081 struct arpt_entry *iter;
1082
1083 if (copy_from_user(&tmp, user, sizeof(tmp)) != 0)
1084 return -EFAULT;
1085
1086 /* overflow check */
1087 if (tmp.num_counters >= INT_MAX / sizeof(struct xt_counters))
1088 return -ENOMEM;
1089
1090 newinfo = xt_alloc_table_info(tmp.size);
1091 if (!newinfo)
1092 return -ENOMEM;
1093
1094 /* choose the copy that is on our node/cpu */
1095 loc_cpu_entry = newinfo->entries[raw_smp_processor_id()];
1096 if (copy_from_user(loc_cpu_entry, user + sizeof(tmp),
1097 tmp.size) != 0) {
1098 ret = -EFAULT;
1099 goto free_newinfo;
1100 }
1101
1102 ret = translate_table(newinfo, loc_cpu_entry, &tmp);
1103 if (ret != 0)
1104 goto free_newinfo;
1105
1106 duprintf("arp_tables: Translated table\n");
1107
1108 ret = __do_replace(net, tmp.name, tmp.valid_hooks, newinfo,
1109 tmp.num_counters, tmp.counters);
1110 if (ret)
1111 goto free_newinfo_untrans;
1112 return 0;
1113
1114 free_newinfo_untrans:
1115 xt_entry_foreach(iter, loc_cpu_entry, newinfo->size)
1116 cleanup_entry(iter);
1117 free_newinfo:
1118 xt_free_table_info(newinfo);
1119 return ret;
1120 }
1121
1122 static int do_add_counters(struct net *net, const void __user *user,
1123 unsigned int len, int compat)
1124 {
1125 unsigned int i, curcpu;
1126 struct xt_counters_info tmp;
1127 struct xt_counters *paddc;
1128 unsigned int num_counters;
1129 const char *name;
1130 int size;
1131 void *ptmp;
1132 struct xt_table *t;
1133 const struct xt_table_info *private;
1134 int ret = 0;
1135 void *loc_cpu_entry;
1136 struct arpt_entry *iter;
1137 #ifdef CONFIG_COMPAT
1138 struct compat_xt_counters_info compat_tmp;
1139
1140 if (compat) {
1141 ptmp = &compat_tmp;
1142 size = sizeof(struct compat_xt_counters_info);
1143 } else
1144 #endif
1145 {
1146 ptmp = &tmp;
1147 size = sizeof(struct xt_counters_info);
1148 }
1149
1150 if (copy_from_user(ptmp, user, size) != 0)
1151 return -EFAULT;
1152
1153 #ifdef CONFIG_COMPAT
1154 if (compat) {
1155 num_counters = compat_tmp.num_counters;
1156 name = compat_tmp.name;
1157 } else
1158 #endif
1159 {
1160 num_counters = tmp.num_counters;
1161 name = tmp.name;
1162 }
1163
1164 if (len != size + num_counters * sizeof(struct xt_counters))
1165 return -EINVAL;
1166
1167 paddc = vmalloc_node(len - size, numa_node_id());
1168 if (!paddc)
1169 return -ENOMEM;
1170
1171 if (copy_from_user(paddc, user + size, len - size) != 0) {
1172 ret = -EFAULT;
1173 goto free;
1174 }
1175
1176 t = xt_find_table_lock(net, NFPROTO_ARP, name);
1177 if (!t || IS_ERR(t)) {
1178 ret = t ? PTR_ERR(t) : -ENOENT;
1179 goto free;
1180 }
1181
1182 local_bh_disable();
1183 private = t->private;
1184 if (private->number != num_counters) {
1185 ret = -EINVAL;
1186 goto unlock_up_free;
1187 }
1188
1189 i = 0;
1190 /* Choose the copy that is on our node */
1191 curcpu = smp_processor_id();
1192 loc_cpu_entry = private->entries[curcpu];
1193 xt_info_wrlock(curcpu);
1194 xt_entry_foreach(iter, loc_cpu_entry, private->size) {
1195 ADD_COUNTER(iter->counters, paddc[i].bcnt, paddc[i].pcnt);
1196 ++i;
1197 }
1198 xt_info_wrunlock(curcpu);
1199 unlock_up_free:
1200 local_bh_enable();
1201 xt_table_unlock(t);
1202 module_put(t->me);
1203 free:
1204 vfree(paddc);
1205
1206 return ret;
1207 }
1208
1209 #ifdef CONFIG_COMPAT
1210 static inline void compat_release_entry(struct compat_arpt_entry *e)
1211 {
1212 struct arpt_entry_target *t;
1213
1214 t = compat_arpt_get_target(e);
1215 module_put(t->u.kernel.target->me);
1216 }
1217
1218 static inline int
1219 check_compat_entry_size_and_hooks(struct compat_arpt_entry *e,
1220 struct xt_table_info *newinfo,
1221 unsigned int *size,
1222 const unsigned char *base,
1223 const unsigned char *limit,
1224 const unsigned int *hook_entries,
1225 const unsigned int *underflows,
1226 const char *name)
1227 {
1228 struct arpt_entry_target *t;
1229 struct xt_target *target;
1230 unsigned int entry_offset;
1231 int ret, off, h;
1232
1233 duprintf("check_compat_entry_size_and_hooks %p\n", e);
1234 if ((unsigned long)e % __alignof__(struct compat_arpt_entry) != 0 ||
1235 (unsigned char *)e + sizeof(struct compat_arpt_entry) >= limit) {
1236 duprintf("Bad offset %p, limit = %p\n", e, limit);
1237 return -EINVAL;
1238 }
1239
1240 if (e->next_offset < sizeof(struct compat_arpt_entry) +
1241 sizeof(struct compat_xt_entry_target)) {
1242 duprintf("checking: element %p size %u\n",
1243 e, e->next_offset);
1244 return -EINVAL;
1245 }
1246
1247 /* For purposes of check_entry casting the compat entry is fine */
1248 ret = check_entry((struct arpt_entry *)e, name);
1249 if (ret)
1250 return ret;
1251
1252 off = sizeof(struct arpt_entry) - sizeof(struct compat_arpt_entry);
1253 entry_offset = (void *)e - (void *)base;
1254
1255 t = compat_arpt_get_target(e);
1256 target = xt_request_find_target(NFPROTO_ARP, t->u.user.name,
1257 t->u.user.revision);
1258 if (IS_ERR(target)) {
1259 duprintf("check_compat_entry_size_and_hooks: `%s' not found\n",
1260 t->u.user.name);
1261 ret = PTR_ERR(target);
1262 goto out;
1263 }
1264 t->u.kernel.target = target;
1265
1266 off += xt_compat_target_offset(target);
1267 *size += off;
1268 ret = xt_compat_add_offset(NFPROTO_ARP, entry_offset, off);
1269 if (ret)
1270 goto release_target;
1271
1272 /* Check hooks & underflows */
1273 for (h = 0; h < NF_ARP_NUMHOOKS; h++) {
1274 if ((unsigned char *)e - base == hook_entries[h])
1275 newinfo->hook_entry[h] = hook_entries[h];
1276 if ((unsigned char *)e - base == underflows[h])
1277 newinfo->underflow[h] = underflows[h];
1278 }
1279
1280 /* Clear counters and comefrom */
1281 memset(&e->counters, 0, sizeof(e->counters));
1282 e->comefrom = 0;
1283 return 0;
1284
1285 release_target:
1286 module_put(t->u.kernel.target->me);
1287 out:
1288 return ret;
1289 }
1290
1291 static int
1292 compat_copy_entry_from_user(struct compat_arpt_entry *e, void **dstptr,
1293 unsigned int *size, const char *name,
1294 struct xt_table_info *newinfo, unsigned char *base)
1295 {
1296 struct arpt_entry_target *t;
1297 struct xt_target *target;
1298 struct arpt_entry *de;
1299 unsigned int origsize;
1300 int ret, h;
1301
1302 ret = 0;
1303 origsize = *size;
1304 de = (struct arpt_entry *)*dstptr;
1305 memcpy(de, e, sizeof(struct arpt_entry));
1306 memcpy(&de->counters, &e->counters, sizeof(e->counters));
1307
1308 *dstptr += sizeof(struct arpt_entry);
1309 *size += sizeof(struct arpt_entry) - sizeof(struct compat_arpt_entry);
1310
1311 de->target_offset = e->target_offset - (origsize - *size);
1312 t = compat_arpt_get_target(e);
1313 target = t->u.kernel.target;
1314 xt_compat_target_from_user(t, dstptr, size);
1315
1316 de->next_offset = e->next_offset - (origsize - *size);
1317 for (h = 0; h < NF_ARP_NUMHOOKS; h++) {
1318 if ((unsigned char *)de - base < newinfo->hook_entry[h])
1319 newinfo->hook_entry[h] -= origsize - *size;
1320 if ((unsigned char *)de - base < newinfo->underflow[h])
1321 newinfo->underflow[h] -= origsize - *size;
1322 }
1323 return ret;
1324 }
1325
1326 static int translate_compat_table(const char *name,
1327 unsigned int valid_hooks,
1328 struct xt_table_info **pinfo,
1329 void **pentry0,
1330 unsigned int total_size,
1331 unsigned int number,
1332 unsigned int *hook_entries,
1333 unsigned int *underflows)
1334 {
1335 unsigned int i, j;
1336 struct xt_table_info *newinfo, *info;
1337 void *pos, *entry0, *entry1;
1338 struct compat_arpt_entry *iter0;
1339 struct arpt_entry *iter1;
1340 unsigned int size;
1341 int ret = 0;
1342
1343 info = *pinfo;
1344 entry0 = *pentry0;
1345 size = total_size;
1346 info->number = number;
1347
1348 /* Init all hooks to impossible value. */
1349 for (i = 0; i < NF_ARP_NUMHOOKS; i++) {
1350 info->hook_entry[i] = 0xFFFFFFFF;
1351 info->underflow[i] = 0xFFFFFFFF;
1352 }
1353
1354 duprintf("translate_compat_table: size %u\n", info->size);
1355 j = 0;
1356 xt_compat_lock(NFPROTO_ARP);
1357 /* Walk through entries, checking offsets. */
1358 xt_entry_foreach(iter0, entry0, total_size) {
1359 ret = check_compat_entry_size_and_hooks(iter0, info, &size,
1360 entry0,
1361 entry0 + total_size,
1362 hook_entries,
1363 underflows,
1364 name);
1365 if (ret != 0)
1366 goto out_unlock;
1367 ++j;
1368 }
1369
1370 ret = -EINVAL;
1371 if (j != number) {
1372 duprintf("translate_compat_table: %u not %u entries\n",
1373 j, number);
1374 goto out_unlock;
1375 }
1376
1377 /* Check hooks all assigned */
1378 for (i = 0; i < NF_ARP_NUMHOOKS; i++) {
1379 /* Only hooks which are valid */
1380 if (!(valid_hooks & (1 << i)))
1381 continue;
1382 if (info->hook_entry[i] == 0xFFFFFFFF) {
1383 duprintf("Invalid hook entry %u %u\n",
1384 i, hook_entries[i]);
1385 goto out_unlock;
1386 }
1387 if (info->underflow[i] == 0xFFFFFFFF) {
1388 duprintf("Invalid underflow %u %u\n",
1389 i, underflows[i]);
1390 goto out_unlock;
1391 }
1392 }
1393
1394 ret = -ENOMEM;
1395 newinfo = xt_alloc_table_info(size);
1396 if (!newinfo)
1397 goto out_unlock;
1398
1399 newinfo->number = number;
1400 for (i = 0; i < NF_ARP_NUMHOOKS; i++) {
1401 newinfo->hook_entry[i] = info->hook_entry[i];
1402 newinfo->underflow[i] = info->underflow[i];
1403 }
1404 entry1 = newinfo->entries[raw_smp_processor_id()];
1405 pos = entry1;
1406 size = total_size;
1407 xt_entry_foreach(iter0, entry0, total_size) {
1408 ret = compat_copy_entry_from_user(iter0, &pos, &size,
1409 name, newinfo, entry1);
1410 if (ret != 0)
1411 break;
1412 }
1413 xt_compat_flush_offsets(NFPROTO_ARP);
1414 xt_compat_unlock(NFPROTO_ARP);
1415 if (ret)
1416 goto free_newinfo;
1417
1418 ret = -ELOOP;
1419 if (!mark_source_chains(newinfo, valid_hooks, entry1))
1420 goto free_newinfo;
1421
1422 i = 0;
1423 xt_entry_foreach(iter1, entry1, newinfo->size) {
1424 ret = check_target(iter1, name);
1425 if (ret != 0)
1426 break;
1427 ++i;
1428 }
1429 if (ret) {
1430 /*
1431 * The first i matches need cleanup_entry (calls ->destroy)
1432 * because they had called ->check already. The other j-i
1433 * entries need only release.
1434 */
1435 int skip = i;
1436 j -= i;
1437 xt_entry_foreach(iter0, entry0, newinfo->size) {
1438 if (skip-- > 0)
1439 continue;
1440 if (j-- == 0)
1441 break;
1442 compat_release_entry(iter0);
1443 }
1444 xt_entry_foreach(iter1, entry1, newinfo->size) {
1445 if (i-- == 0)
1446 break;
1447 cleanup_entry(iter1);
1448 }
1449 xt_free_table_info(newinfo);
1450 return ret;
1451 }
1452
1453 /* And one copy for every other CPU */
1454 for_each_possible_cpu(i)
1455 if (newinfo->entries[i] && newinfo->entries[i] != entry1)
1456 memcpy(newinfo->entries[i], entry1, newinfo->size);
1457
1458 *pinfo = newinfo;
1459 *pentry0 = entry1;
1460 xt_free_table_info(info);
1461 return 0;
1462
1463 free_newinfo:
1464 xt_free_table_info(newinfo);
1465 out:
1466 xt_entry_foreach(iter0, entry0, total_size) {
1467 if (j-- == 0)
1468 break;
1469 compat_release_entry(iter0);
1470 }
1471 return ret;
1472 out_unlock:
1473 xt_compat_flush_offsets(NFPROTO_ARP);
1474 xt_compat_unlock(NFPROTO_ARP);
1475 goto out;
1476 }
1477
1478 struct compat_arpt_replace {
1479 char name[ARPT_TABLE_MAXNAMELEN];
1480 u32 valid_hooks;
1481 u32 num_entries;
1482 u32 size;
1483 u32 hook_entry[NF_ARP_NUMHOOKS];
1484 u32 underflow[NF_ARP_NUMHOOKS];
1485 u32 num_counters;
1486 compat_uptr_t counters;
1487 struct compat_arpt_entry entries[0];
1488 };
1489
1490 static int compat_do_replace(struct net *net, void __user *user,
1491 unsigned int len)
1492 {
1493 int ret;
1494 struct compat_arpt_replace tmp;
1495 struct xt_table_info *newinfo;
1496 void *loc_cpu_entry;
1497 struct arpt_entry *iter;
1498
1499 if (copy_from_user(&tmp, user, sizeof(tmp)) != 0)
1500 return -EFAULT;
1501
1502 /* overflow check */
1503 if (tmp.size >= INT_MAX / num_possible_cpus())
1504 return -ENOMEM;
1505 if (tmp.num_counters >= INT_MAX / sizeof(struct xt_counters))
1506 return -ENOMEM;
1507
1508 newinfo = xt_alloc_table_info(tmp.size);
1509 if (!newinfo)
1510 return -ENOMEM;
1511
1512 /* choose the copy that is on our node/cpu */
1513 loc_cpu_entry = newinfo->entries[raw_smp_processor_id()];
1514 if (copy_from_user(loc_cpu_entry, user + sizeof(tmp), tmp.size) != 0) {
1515 ret = -EFAULT;
1516 goto free_newinfo;
1517 }
1518
1519 ret = translate_compat_table(tmp.name, tmp.valid_hooks,
1520 &newinfo, &loc_cpu_entry, tmp.size,
1521 tmp.num_entries, tmp.hook_entry,
1522 tmp.underflow);
1523 if (ret != 0)
1524 goto free_newinfo;
1525
1526 duprintf("compat_do_replace: Translated table\n");
1527
1528 ret = __do_replace(net, tmp.name, tmp.valid_hooks, newinfo,
1529 tmp.num_counters, compat_ptr(tmp.counters));
1530 if (ret)
1531 goto free_newinfo_untrans;
1532 return 0;
1533
1534 free_newinfo_untrans:
1535 xt_entry_foreach(iter, loc_cpu_entry, newinfo->size)
1536 cleanup_entry(iter);
1537 free_newinfo:
1538 xt_free_table_info(newinfo);
1539 return ret;
1540 }
1541
1542 static int compat_do_arpt_set_ctl(struct sock *sk, int cmd, void __user *user,
1543 unsigned int len)
1544 {
1545 int ret;
1546
1547 if (!capable(CAP_NET_ADMIN))
1548 return -EPERM;
1549
1550 switch (cmd) {
1551 case ARPT_SO_SET_REPLACE:
1552 ret = compat_do_replace(sock_net(sk), user, len);
1553 break;
1554
1555 case ARPT_SO_SET_ADD_COUNTERS:
1556 ret = do_add_counters(sock_net(sk), user, len, 1);
1557 break;
1558
1559 default:
1560 duprintf("do_arpt_set_ctl: unknown request %i\n", cmd);
1561 ret = -EINVAL;
1562 }
1563
1564 return ret;
1565 }
1566
1567 static int compat_copy_entry_to_user(struct arpt_entry *e, void __user **dstptr,
1568 compat_uint_t *size,
1569 struct xt_counters *counters,
1570 unsigned int i)
1571 {
1572 struct arpt_entry_target *t;
1573 struct compat_arpt_entry __user *ce;
1574 u_int16_t target_offset, next_offset;
1575 compat_uint_t origsize;
1576 int ret;
1577
1578 origsize = *size;
1579 ce = (struct compat_arpt_entry __user *)*dstptr;
1580 if (copy_to_user(ce, e, sizeof(struct arpt_entry)) != 0 ||
1581 copy_to_user(&ce->counters, &counters[i],
1582 sizeof(counters[i])) != 0)
1583 return -EFAULT;
1584
1585 *dstptr += sizeof(struct compat_arpt_entry);
1586 *size -= sizeof(struct arpt_entry) - sizeof(struct compat_arpt_entry);
1587
1588 target_offset = e->target_offset - (origsize - *size);
1589
1590 t = arpt_get_target(e);
1591 ret = xt_compat_target_to_user(t, dstptr, size);
1592 if (ret)
1593 return ret;
1594 next_offset = e->next_offset - (origsize - *size);
1595 if (put_user(target_offset, &ce->target_offset) != 0 ||
1596 put_user(next_offset, &ce->next_offset) != 0)
1597 return -EFAULT;
1598 return 0;
1599 }
1600
1601 static int compat_copy_entries_to_user(unsigned int total_size,
1602 struct xt_table *table,
1603 void __user *userptr)
1604 {
1605 struct xt_counters *counters;
1606 const struct xt_table_info *private = table->private;
1607 void __user *pos;
1608 unsigned int size;
1609 int ret = 0;
1610 void *loc_cpu_entry;
1611 unsigned int i = 0;
1612 struct arpt_entry *iter;
1613
1614 counters = alloc_counters(table);
1615 if (IS_ERR(counters))
1616 return PTR_ERR(counters);
1617
1618 /* choose the copy on our node/cpu */
1619 loc_cpu_entry = private->entries[raw_smp_processor_id()];
1620 pos = userptr;
1621 size = total_size;
1622 xt_entry_foreach(iter, loc_cpu_entry, total_size) {
1623 ret = compat_copy_entry_to_user(iter, &pos,
1624 &size, counters, i++);
1625 if (ret != 0)
1626 break;
1627 }
1628 vfree(counters);
1629 return ret;
1630 }
1631
1632 struct compat_arpt_get_entries {
1633 char name[ARPT_TABLE_MAXNAMELEN];
1634 compat_uint_t size;
1635 struct compat_arpt_entry entrytable[0];
1636 };
1637
1638 static int compat_get_entries(struct net *net,
1639 struct compat_arpt_get_entries __user *uptr,
1640 int *len)
1641 {
1642 int ret;
1643 struct compat_arpt_get_entries get;
1644 struct xt_table *t;
1645
1646 if (*len < sizeof(get)) {
1647 duprintf("compat_get_entries: %u < %zu\n", *len, sizeof(get));
1648 return -EINVAL;
1649 }
1650 if (copy_from_user(&get, uptr, sizeof(get)) != 0)
1651 return -EFAULT;
1652 if (*len != sizeof(struct compat_arpt_get_entries) + get.size) {
1653 duprintf("compat_get_entries: %u != %zu\n",
1654 *len, sizeof(get) + get.size);
1655 return -EINVAL;
1656 }
1657
1658 xt_compat_lock(NFPROTO_ARP);
1659 t = xt_find_table_lock(net, NFPROTO_ARP, get.name);
1660 if (t && !IS_ERR(t)) {
1661 const struct xt_table_info *private = t->private;
1662 struct xt_table_info info;
1663
1664 duprintf("t->private->number = %u\n", private->number);
1665 ret = compat_table_info(private, &info);
1666 if (!ret && get.size == info.size) {
1667 ret = compat_copy_entries_to_user(private->size,
1668 t, uptr->entrytable);
1669 } else if (!ret) {
1670 duprintf("compat_get_entries: I've got %u not %u!\n",
1671 private->size, get.size);
1672 ret = -EAGAIN;
1673 }
1674 xt_compat_flush_offsets(NFPROTO_ARP);
1675 module_put(t->me);
1676 xt_table_unlock(t);
1677 } else
1678 ret = t ? PTR_ERR(t) : -ENOENT;
1679
1680 xt_compat_unlock(NFPROTO_ARP);
1681 return ret;
1682 }
1683
1684 static int do_arpt_get_ctl(struct sock *, int, void __user *, int *);
1685
1686 static int compat_do_arpt_get_ctl(struct sock *sk, int cmd, void __user *user,
1687 int *len)
1688 {
1689 int ret;
1690
1691 if (!capable(CAP_NET_ADMIN))
1692 return -EPERM;
1693
1694 switch (cmd) {
1695 case ARPT_SO_GET_INFO:
1696 ret = get_info(sock_net(sk), user, len, 1);
1697 break;
1698 case ARPT_SO_GET_ENTRIES:
1699 ret = compat_get_entries(sock_net(sk), user, len);
1700 break;
1701 default:
1702 ret = do_arpt_get_ctl(sk, cmd, user, len);
1703 }
1704 return ret;
1705 }
1706 #endif
1707
1708 static int do_arpt_set_ctl(struct sock *sk, int cmd, void __user *user, unsigned int len)
1709 {
1710 int ret;
1711
1712 if (!capable(CAP_NET_ADMIN))
1713 return -EPERM;
1714
1715 switch (cmd) {
1716 case ARPT_SO_SET_REPLACE:
1717 ret = do_replace(sock_net(sk), user, len);
1718 break;
1719
1720 case ARPT_SO_SET_ADD_COUNTERS:
1721 ret = do_add_counters(sock_net(sk), user, len, 0);
1722 break;
1723
1724 default:
1725 duprintf("do_arpt_set_ctl: unknown request %i\n", cmd);
1726 ret = -EINVAL;
1727 }
1728
1729 return ret;
1730 }
1731
1732 static int do_arpt_get_ctl(struct sock *sk, int cmd, void __user *user, int *len)
1733 {
1734 int ret;
1735
1736 if (!capable(CAP_NET_ADMIN))
1737 return -EPERM;
1738
1739 switch (cmd) {
1740 case ARPT_SO_GET_INFO:
1741 ret = get_info(sock_net(sk), user, len, 0);
1742 break;
1743
1744 case ARPT_SO_GET_ENTRIES:
1745 ret = get_entries(sock_net(sk), user, len);
1746 break;
1747
1748 case ARPT_SO_GET_REVISION_TARGET: {
1749 struct xt_get_revision rev;
1750
1751 if (*len != sizeof(rev)) {
1752 ret = -EINVAL;
1753 break;
1754 }
1755 if (copy_from_user(&rev, user, sizeof(rev)) != 0) {
1756 ret = -EFAULT;
1757 break;
1758 }
1759
1760 try_then_request_module(xt_find_revision(NFPROTO_ARP, rev.name,
1761 rev.revision, 1, &ret),
1762 "arpt_%s", rev.name);
1763 break;
1764 }
1765
1766 default:
1767 duprintf("do_arpt_get_ctl: unknown request %i\n", cmd);
1768 ret = -EINVAL;
1769 }
1770
1771 return ret;
1772 }
1773
1774 struct xt_table *arpt_register_table(struct net *net,
1775 const struct xt_table *table,
1776 const struct arpt_replace *repl)
1777 {
1778 int ret;
1779 struct xt_table_info *newinfo;
1780 struct xt_table_info bootstrap = {0};
1781 void *loc_cpu_entry;
1782 struct xt_table *new_table;
1783
1784 newinfo = xt_alloc_table_info(repl->size);
1785 if (!newinfo) {
1786 ret = -ENOMEM;
1787 goto out;
1788 }
1789
1790 /* choose the copy on our node/cpu */
1791 loc_cpu_entry = newinfo->entries[raw_smp_processor_id()];
1792 memcpy(loc_cpu_entry, repl->entries, repl->size);
1793
1794 ret = translate_table(newinfo, loc_cpu_entry, repl);
1795 duprintf("arpt_register_table: translate table gives %d\n", ret);
1796 if (ret != 0)
1797 goto out_free;
1798
1799 new_table = xt_register_table(net, table, &bootstrap, newinfo);
1800 if (IS_ERR(new_table)) {
1801 ret = PTR_ERR(new_table);
1802 goto out_free;
1803 }
1804 return new_table;
1805
1806 out_free:
1807 xt_free_table_info(newinfo);
1808 out:
1809 return ERR_PTR(ret);
1810 }
1811
1812 void arpt_unregister_table(struct xt_table *table)
1813 {
1814 struct xt_table_info *private;
1815 void *loc_cpu_entry;
1816 struct module *table_owner = table->me;
1817 struct arpt_entry *iter;
1818
1819 private = xt_unregister_table(table);
1820
1821 /* Decrease module usage counts and free resources */
1822 loc_cpu_entry = private->entries[raw_smp_processor_id()];
1823 xt_entry_foreach(iter, loc_cpu_entry, private->size)
1824 cleanup_entry(iter);
1825 if (private->number > private->initial_entries)
1826 module_put(table_owner);
1827 xt_free_table_info(private);
1828 }
1829
1830 /* The built-in targets: standard (NULL) and error. */
1831 static struct xt_target arpt_standard_target __read_mostly = {
1832 .name = ARPT_STANDARD_TARGET,
1833 .targetsize = sizeof(int),
1834 .family = NFPROTO_ARP,
1835 #ifdef CONFIG_COMPAT
1836 .compatsize = sizeof(compat_int_t),
1837 .compat_from_user = compat_standard_from_user,
1838 .compat_to_user = compat_standard_to_user,
1839 #endif
1840 };
1841
1842 static struct xt_target arpt_error_target __read_mostly = {
1843 .name = ARPT_ERROR_TARGET,
1844 .target = arpt_error,
1845 .targetsize = ARPT_FUNCTION_MAXNAMELEN,
1846 .family = NFPROTO_ARP,
1847 };
1848
1849 static struct nf_sockopt_ops arpt_sockopts = {
1850 .pf = PF_INET,
1851 .set_optmin = ARPT_BASE_CTL,
1852 .set_optmax = ARPT_SO_SET_MAX+1,
1853 .set = do_arpt_set_ctl,
1854 #ifdef CONFIG_COMPAT
1855 .compat_set = compat_do_arpt_set_ctl,
1856 #endif
1857 .get_optmin = ARPT_BASE_CTL,
1858 .get_optmax = ARPT_SO_GET_MAX+1,
1859 .get = do_arpt_get_ctl,
1860 #ifdef CONFIG_COMPAT
1861 .compat_get = compat_do_arpt_get_ctl,
1862 #endif
1863 .owner = THIS_MODULE,
1864 };
1865
1866 static int __net_init arp_tables_net_init(struct net *net)
1867 {
1868 return xt_proto_init(net, NFPROTO_ARP);
1869 }
1870
1871 static void __net_exit arp_tables_net_exit(struct net *net)
1872 {
1873 xt_proto_fini(net, NFPROTO_ARP);
1874 }
1875
1876 static struct pernet_operations arp_tables_net_ops = {
1877 .init = arp_tables_net_init,
1878 .exit = arp_tables_net_exit,
1879 };
1880
1881 static int __init arp_tables_init(void)
1882 {
1883 int ret;
1884
1885 ret = register_pernet_subsys(&arp_tables_net_ops);
1886 if (ret < 0)
1887 goto err1;
1888
1889 /* Noone else will be downing sem now, so we won't sleep */
1890 ret = xt_register_target(&arpt_standard_target);
1891 if (ret < 0)
1892 goto err2;
1893 ret = xt_register_target(&arpt_error_target);
1894 if (ret < 0)
1895 goto err3;
1896
1897 /* Register setsockopt */
1898 ret = nf_register_sockopt(&arpt_sockopts);
1899 if (ret < 0)
1900 goto err4;
1901
1902 printk(KERN_INFO "arp_tables: (C) 2002 David S. Miller\n");
1903 return 0;
1904
1905 err4:
1906 xt_unregister_target(&arpt_error_target);
1907 err3:
1908 xt_unregister_target(&arpt_standard_target);
1909 err2:
1910 unregister_pernet_subsys(&arp_tables_net_ops);
1911 err1:
1912 return ret;
1913 }
1914
1915 static void __exit arp_tables_fini(void)
1916 {
1917 nf_unregister_sockopt(&arpt_sockopts);
1918 xt_unregister_target(&arpt_error_target);
1919 xt_unregister_target(&arpt_standard_target);
1920 unregister_pernet_subsys(&arp_tables_net_ops);
1921 }
1922
1923 EXPORT_SYMBOL(arpt_register_table);
1924 EXPORT_SYMBOL(arpt_unregister_table);
1925 EXPORT_SYMBOL(arpt_do_table);
1926
1927 module_init(arp_tables_init);
1928 module_exit(arp_tables_fini);
Linux 2.6 ibm-acpi/thinkpad-acpi driver git tree