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3fac340a28d5394bd95bd649d5bcee3dcb3d24df
[GitHub/mt8127/android_kernel_alcatel_ttab.git] / net / ipv4 / netfilter / arp_tables.c
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) WARN_ON(!(x))
53 #else
54 #define ARP_NF_ASSERT(x)
55 #endif
56
57 void *arpt_alloc_initial_table(const struct xt_table *info)
58 {
59 return xt_alloc_initial_table(arpt, ARPT);
60 }
61 EXPORT_SYMBOL_GPL(arpt_alloc_initial_table);
62
63 static inline int arp_devaddr_compare(const struct arpt_devaddr_info *ap,
64 const char *hdr_addr, int len)
65 {
66 int i, ret;
67
68 if (len > ARPT_DEV_ADDR_LEN_MAX)
69 len = ARPT_DEV_ADDR_LEN_MAX;
70
71 ret = 0;
72 for (i = 0; i < len; i++)
73 ret |= (hdr_addr[i] ^ ap->addr[i]) & ap->mask[i];
74
75 return ret != 0;
76 }
77
78 /*
79 * Unfortunatly, _b and _mask are not aligned to an int (or long int)
80 * Some arches dont care, unrolling the loop is a win on them.
81 * For other arches, we only have a 16bit alignement.
82 */
83 static unsigned long ifname_compare(const char *_a, const char *_b, const char *_mask)
84 {
85 #ifdef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS
86 unsigned long ret = ifname_compare_aligned(_a, _b, _mask);
87 #else
88 unsigned long ret = 0;
89 const u16 *a = (const u16 *)_a;
90 const u16 *b = (const u16 *)_b;
91 const u16 *mask = (const u16 *)_mask;
92 int i;
93
94 for (i = 0; i < IFNAMSIZ/sizeof(u16); i++)
95 ret |= (a[i] ^ b[i]) & mask[i];
96 #endif
97 return ret;
98 }
99
100 /* Returns whether packet matches rule or not. */
101 static inline int arp_packet_match(const struct arphdr *arphdr,
102 struct net_device *dev,
103 const char *indev,
104 const char *outdev,
105 const struct arpt_arp *arpinfo)
106 {
107 const char *arpptr = (char *)(arphdr + 1);
108 const char *src_devaddr, *tgt_devaddr;
109 __be32 src_ipaddr, tgt_ipaddr;
110 long ret;
111
112 #define FWINV(bool, invflg) ((bool) ^ !!(arpinfo->invflags & (invflg)))
113
114 if (FWINV((arphdr->ar_op & arpinfo->arpop_mask) != arpinfo->arpop,
115 ARPT_INV_ARPOP)) {
116 dprintf("ARP operation field mismatch.\n");
117 dprintf("ar_op: %04x info->arpop: %04x info->arpop_mask: %04x\n",
118 arphdr->ar_op, arpinfo->arpop, arpinfo->arpop_mask);
119 return 0;
120 }
121
122 if (FWINV((arphdr->ar_hrd & arpinfo->arhrd_mask) != arpinfo->arhrd,
123 ARPT_INV_ARPHRD)) {
124 dprintf("ARP hardware address format mismatch.\n");
125 dprintf("ar_hrd: %04x info->arhrd: %04x info->arhrd_mask: %04x\n",
126 arphdr->ar_hrd, arpinfo->arhrd, arpinfo->arhrd_mask);
127 return 0;
128 }
129
130 if (FWINV((arphdr->ar_pro & arpinfo->arpro_mask) != arpinfo->arpro,
131 ARPT_INV_ARPPRO)) {
132 dprintf("ARP protocol address format mismatch.\n");
133 dprintf("ar_pro: %04x info->arpro: %04x info->arpro_mask: %04x\n",
134 arphdr->ar_pro, arpinfo->arpro, arpinfo->arpro_mask);
135 return 0;
136 }
137
138 if (FWINV((arphdr->ar_hln & arpinfo->arhln_mask) != arpinfo->arhln,
139 ARPT_INV_ARPHLN)) {
140 dprintf("ARP hardware address length mismatch.\n");
141 dprintf("ar_hln: %02x info->arhln: %02x info->arhln_mask: %02x\n",
142 arphdr->ar_hln, arpinfo->arhln, arpinfo->arhln_mask);
143 return 0;
144 }
145
146 src_devaddr = arpptr;
147 arpptr += dev->addr_len;
148 memcpy(&src_ipaddr, arpptr, sizeof(u32));
149 arpptr += sizeof(u32);
150 tgt_devaddr = arpptr;
151 arpptr += dev->addr_len;
152 memcpy(&tgt_ipaddr, arpptr, sizeof(u32));
153
154 if (FWINV(arp_devaddr_compare(&arpinfo->src_devaddr, src_devaddr, dev->addr_len),
155 ARPT_INV_SRCDEVADDR) ||
156 FWINV(arp_devaddr_compare(&arpinfo->tgt_devaddr, tgt_devaddr, dev->addr_len),
157 ARPT_INV_TGTDEVADDR)) {
158 dprintf("Source or target device address mismatch.\n");
159
160 return 0;
161 }
162
163 if (FWINV((src_ipaddr & arpinfo->smsk.s_addr) != arpinfo->src.s_addr,
164 ARPT_INV_SRCIP) ||
165 FWINV(((tgt_ipaddr & arpinfo->tmsk.s_addr) != arpinfo->tgt.s_addr),
166 ARPT_INV_TGTIP)) {
167 dprintf("Source or target IP address mismatch.\n");
168
169 dprintf("SRC: %pI4. Mask: %pI4. Target: %pI4.%s\n",
170 &src_ipaddr,
171 &arpinfo->smsk.s_addr,
172 &arpinfo->src.s_addr,
173 arpinfo->invflags & ARPT_INV_SRCIP ? " (INV)" : "");
174 dprintf("TGT: %pI4 Mask: %pI4 Target: %pI4.%s\n",
175 &tgt_ipaddr,
176 &arpinfo->tmsk.s_addr,
177 &arpinfo->tgt.s_addr,
178 arpinfo->invflags & ARPT_INV_TGTIP ? " (INV)" : "");
179 return 0;
180 }
181
182 /* Look for ifname matches. */
183 ret = ifname_compare(indev, arpinfo->iniface, arpinfo->iniface_mask);
184
185 if (FWINV(ret != 0, ARPT_INV_VIA_IN)) {
186 dprintf("VIA in mismatch (%s vs %s).%s\n",
187 indev, arpinfo->iniface,
188 arpinfo->invflags&ARPT_INV_VIA_IN ?" (INV)":"");
189 return 0;
190 }
191
192 ret = ifname_compare(outdev, arpinfo->outiface, arpinfo->outiface_mask);
193
194 if (FWINV(ret != 0, ARPT_INV_VIA_OUT)) {
195 dprintf("VIA out mismatch (%s vs %s).%s\n",
196 outdev, arpinfo->outiface,
197 arpinfo->invflags&ARPT_INV_VIA_OUT ?" (INV)":"");
198 return 0;
199 }
200
201 return 1;
202 #undef FWINV
203 }
204
205 static inline int arp_checkentry(const struct arpt_arp *arp)
206 {
207 if (arp->flags & ~ARPT_F_MASK) {
208 duprintf("Unknown flag bits set: %08X\n",
209 arp->flags & ~ARPT_F_MASK);
210 return 0;
211 }
212 if (arp->invflags & ~ARPT_INV_MASK) {
213 duprintf("Unknown invflag bits set: %08X\n",
214 arp->invflags & ~ARPT_INV_MASK);
215 return 0;
216 }
217
218 return 1;
219 }
220
221 static unsigned int
222 arpt_error(struct sk_buff *skb, const struct xt_action_param *par)
223 {
224 if (net_ratelimit())
225 pr_err("arp_tables: error: '%s'\n",
226 (const char *)par->targinfo);
227
228 return NF_DROP;
229 }
230
231 static inline const struct xt_entry_target *
232 arpt_get_target_c(const struct arpt_entry *e)
233 {
234 return arpt_get_target((struct arpt_entry *)e);
235 }
236
237 static inline struct arpt_entry *
238 get_entry(const void *base, unsigned int offset)
239 {
240 return (struct arpt_entry *)(base + offset);
241 }
242
243 static inline __pure
244 struct arpt_entry *arpt_next_entry(const struct arpt_entry *entry)
245 {
246 return (void *)entry + entry->next_offset;
247 }
248
249 unsigned int arpt_do_table(struct sk_buff *skb,
250 unsigned int hook,
251 const struct net_device *in,
252 const struct net_device *out,
253 struct xt_table *table)
254 {
255 static const char nulldevname[IFNAMSIZ] __attribute__((aligned(sizeof(long))));
256 unsigned int verdict = NF_DROP;
257 const struct arphdr *arp;
258 struct arpt_entry *e, *back;
259 const char *indev, *outdev;
260 void *table_base;
261 const struct xt_table_info *private;
262 struct xt_action_param acpar;
263
264 if (!pskb_may_pull(skb, arp_hdr_len(skb->dev)))
265 return NF_DROP;
266
267 indev = in ? in->name : nulldevname;
268 outdev = out ? out->name : nulldevname;
269
270 xt_info_rdlock_bh();
271 private = table->private;
272 table_base = private->entries[smp_processor_id()];
273
274 e = get_entry(table_base, private->hook_entry[hook]);
275 back = get_entry(table_base, private->underflow[hook]);
276
277 acpar.in = in;
278 acpar.out = out;
279 acpar.hooknum = hook;
280 acpar.family = NFPROTO_ARP;
281 acpar.hotdrop = false;
282
283 arp = arp_hdr(skb);
284 do {
285 const struct xt_entry_target *t;
286
287 if (!arp_packet_match(arp, skb->dev, indev, outdev, &e->arp)) {
288 e = arpt_next_entry(e);
289 continue;
290 }
291
292 ADD_COUNTER(e->counters, arp_hdr_len(skb->dev), 1);
293
294 t = arpt_get_target_c(e);
295
296 /* Standard target? */
297 if (!t->u.kernel.target->target) {
298 int v;
299
300 v = ((struct xt_standard_target *)t)->verdict;
301 if (v < 0) {
302 /* Pop from stack? */
303 if (v != XT_RETURN) {
304 verdict = (unsigned)(-v) - 1;
305 break;
306 }
307 e = back;
308 back = get_entry(table_base, back->comefrom);
309 continue;
310 }
311 if (table_base + v
312 != arpt_next_entry(e)) {
313 /* Save old back ptr in next entry */
314 struct arpt_entry *next = arpt_next_entry(e);
315 next->comefrom = (void *)back - table_base;
316
317 /* set back pointer to next entry */
318 back = next;
319 }
320
321 e = get_entry(table_base, v);
322 continue;
323 }
324
325 /* Targets which reenter must return
326 * abs. verdicts
327 */
328 acpar.target = t->u.kernel.target;
329 acpar.targinfo = t->data;
330 verdict = t->u.kernel.target->target(skb, &acpar);
331
332 /* Target might have changed stuff. */
333 arp = arp_hdr(skb);
334
335 if (verdict == XT_CONTINUE)
336 e = arpt_next_entry(e);
337 else
338 /* Verdict */
339 break;
340 } while (!acpar.hotdrop);
341 xt_info_rdunlock_bh();
342
343 if (acpar.hotdrop)
344 return NF_DROP;
345 else
346 return verdict;
347 }
348
349 /* All zeroes == unconditional rule. */
350 static inline bool unconditional(const struct arpt_arp *arp)
351 {
352 static const struct arpt_arp uncond;
353
354 return memcmp(arp, &uncond, sizeof(uncond)) == 0;
355 }
356
357 /* Figures out from what hook each rule can be called: returns 0 if
358 * there are loops. Puts hook bitmask in comefrom.
359 */
360 static int mark_source_chains(const struct xt_table_info *newinfo,
361 unsigned int valid_hooks, void *entry0)
362 {
363 unsigned int hook;
364
365 /* No recursion; use packet counter to save back ptrs (reset
366 * to 0 as we leave), and comefrom to save source hook bitmask.
367 */
368 for (hook = 0; hook < NF_ARP_NUMHOOKS; hook++) {
369 unsigned int pos = newinfo->hook_entry[hook];
370 struct arpt_entry *e
371 = (struct arpt_entry *)(entry0 + pos);
372
373 if (!(valid_hooks & (1 << hook)))
374 continue;
375
376 /* Set initial back pointer. */
377 e->counters.pcnt = pos;
378
379 for (;;) {
380 const struct xt_standard_target *t
381 = (void *)arpt_get_target_c(e);
382 int visited = e->comefrom & (1 << hook);
383
384 if (e->comefrom & (1 << NF_ARP_NUMHOOKS)) {
385 pr_notice("arptables: loop hook %u pos %u %08X.\n",
386 hook, pos, e->comefrom);
387 return 0;
388 }
389 e->comefrom
390 |= ((1 << hook) | (1 << NF_ARP_NUMHOOKS));
391
392 /* Unconditional return/END. */
393 if ((e->target_offset == sizeof(struct arpt_entry) &&
394 (strcmp(t->target.u.user.name,
395 XT_STANDARD_TARGET) == 0) &&
396 t->verdict < 0 && unconditional(&e->arp)) ||
397 visited) {
398 unsigned int oldpos, size;
399
400 if ((strcmp(t->target.u.user.name,
401 XT_STANDARD_TARGET) == 0) &&
402 t->verdict < -NF_MAX_VERDICT - 1) {
403 duprintf("mark_source_chains: bad "
404 "negative verdict (%i)\n",
405 t->verdict);
406 return 0;
407 }
408
409 /* Return: backtrack through the last
410 * big jump.
411 */
412 do {
413 e->comefrom ^= (1<<NF_ARP_NUMHOOKS);
414 oldpos = pos;
415 pos = e->counters.pcnt;
416 e->counters.pcnt = 0;
417
418 /* We're at the start. */
419 if (pos == oldpos)
420 goto next;
421
422 e = (struct arpt_entry *)
423 (entry0 + pos);
424 } while (oldpos == pos + e->next_offset);
425
426 /* Move along one */
427 size = e->next_offset;
428 e = (struct arpt_entry *)
429 (entry0 + pos + size);
430 e->counters.pcnt = pos;
431 pos += size;
432 } else {
433 int newpos = t->verdict;
434
435 if (strcmp(t->target.u.user.name,
436 XT_STANDARD_TARGET) == 0 &&
437 newpos >= 0) {
438 if (newpos > newinfo->size -
439 sizeof(struct arpt_entry)) {
440 duprintf("mark_source_chains: "
441 "bad verdict (%i)\n",
442 newpos);
443 return 0;
444 }
445
446 /* This a jump; chase it. */
447 duprintf("Jump rule %u -> %u\n",
448 pos, newpos);
449 } else {
450 /* ... this is a fallthru */
451 newpos = pos + e->next_offset;
452 }
453 e = (struct arpt_entry *)
454 (entry0 + newpos);
455 e->counters.pcnt = pos;
456 pos = newpos;
457 }
458 }
459 next:
460 duprintf("Finished chain %u\n", hook);
461 }
462 return 1;
463 }
464
465 static inline int check_entry(const struct arpt_entry *e, const char *name)
466 {
467 const struct xt_entry_target *t;
468
469 if (!arp_checkentry(&e->arp)) {
470 duprintf("arp_tables: arp check failed %p %s.\n", e, name);
471 return -EINVAL;
472 }
473
474 if (e->target_offset + sizeof(struct xt_entry_target) > e->next_offset)
475 return -EINVAL;
476
477 t = arpt_get_target_c(e);
478 if (e->target_offset + t->u.target_size > e->next_offset)
479 return -EINVAL;
480
481 return 0;
482 }
483
484 static inline int check_target(struct arpt_entry *e, const char *name)
485 {
486 struct xt_entry_target *t = arpt_get_target(e);
487 int ret;
488 struct xt_tgchk_param par = {
489 .table = name,
490 .entryinfo = e,
491 .target = t->u.kernel.target,
492 .targinfo = t->data,
493 .hook_mask = e->comefrom,
494 .family = NFPROTO_ARP,
495 };
496
497 ret = xt_check_target(&par, t->u.target_size - sizeof(*t), 0, false);
498 if (ret < 0) {
499 duprintf("arp_tables: check failed for `%s'.\n",
500 t->u.kernel.target->name);
501 return ret;
502 }
503 return 0;
504 }
505
506 static inline int
507 find_check_entry(struct arpt_entry *e, const char *name, unsigned int size)
508 {
509 struct xt_entry_target *t;
510 struct xt_target *target;
511 int ret;
512
513 ret = check_entry(e, name);
514 if (ret)
515 return ret;
516
517 t = arpt_get_target(e);
518 target = xt_request_find_target(NFPROTO_ARP, t->u.user.name,
519 t->u.user.revision);
520 if (IS_ERR(target)) {
521 duprintf("find_check_entry: `%s' not found\n", t->u.user.name);
522 ret = PTR_ERR(target);
523 goto out;
524 }
525 t->u.kernel.target = target;
526
527 ret = check_target(e, name);
528 if (ret)
529 goto err;
530 return 0;
531 err:
532 module_put(t->u.kernel.target->me);
533 out:
534 return ret;
535 }
536
537 static bool check_underflow(const struct arpt_entry *e)
538 {
539 const struct xt_entry_target *t;
540 unsigned int verdict;
541
542 if (!unconditional(&e->arp))
543 return false;
544 t = arpt_get_target_c(e);
545 if (strcmp(t->u.user.name, XT_STANDARD_TARGET) != 0)
546 return false;
547 verdict = ((struct xt_standard_target *)t)->verdict;
548 verdict = -verdict - 1;
549 return verdict == NF_DROP || verdict == NF_ACCEPT;
550 }
551
552 static inline int check_entry_size_and_hooks(struct arpt_entry *e,
553 struct xt_table_info *newinfo,
554 const unsigned char *base,
555 const unsigned char *limit,
556 const unsigned int *hook_entries,
557 const unsigned int *underflows,
558 unsigned int valid_hooks)
559 {
560 unsigned int h;
561
562 if ((unsigned long)e % __alignof__(struct arpt_entry) != 0 ||
563 (unsigned char *)e + sizeof(struct arpt_entry) >= limit) {
564 duprintf("Bad offset %p\n", e);
565 return -EINVAL;
566 }
567
568 if (e->next_offset
569 < sizeof(struct arpt_entry) + sizeof(struct xt_entry_target)) {
570 duprintf("checking: element %p size %u\n",
571 e, e->next_offset);
572 return -EINVAL;
573 }
574
575 /* Check hooks & underflows */
576 for (h = 0; h < NF_ARP_NUMHOOKS; h++) {
577 if (!(valid_hooks & (1 << h)))
578 continue;
579 if ((unsigned char *)e - base == hook_entries[h])
580 newinfo->hook_entry[h] = hook_entries[h];
581 if ((unsigned char *)e - base == underflows[h]) {
582 if (!check_underflow(e)) {
583 pr_err("Underflows must be unconditional and "
584 "use the STANDARD target with "
585 "ACCEPT/DROP\n");
586 return -EINVAL;
587 }
588 newinfo->underflow[h] = underflows[h];
589 }
590 }
591
592 /* Clear counters and comefrom */
593 e->counters = ((struct xt_counters) { 0, 0 });
594 e->comefrom = 0;
595 return 0;
596 }
597
598 static inline void cleanup_entry(struct arpt_entry *e)
599 {
600 struct xt_tgdtor_param par;
601 struct xt_entry_target *t;
602
603 t = arpt_get_target(e);
604 par.target = t->u.kernel.target;
605 par.targinfo = t->data;
606 par.family = NFPROTO_ARP;
607 if (par.target->destroy != NULL)
608 par.target->destroy(&par);
609 module_put(par.target->me);
610 }
611
612 /* Checks and translates the user-supplied table segment (held in
613 * newinfo).
614 */
615 static int translate_table(struct xt_table_info *newinfo, void *entry0,
616 const struct arpt_replace *repl)
617 {
618 struct arpt_entry *iter;
619 unsigned int i;
620 int ret = 0;
621
622 newinfo->size = repl->size;
623 newinfo->number = repl->num_entries;
624
625 /* Init all hooks to impossible value. */
626 for (i = 0; i < NF_ARP_NUMHOOKS; i++) {
627 newinfo->hook_entry[i] = 0xFFFFFFFF;
628 newinfo->underflow[i] = 0xFFFFFFFF;
629 }
630
631 duprintf("translate_table: size %u\n", newinfo->size);
632 i = 0;
633
634 /* Walk through entries, checking offsets. */
635 xt_entry_foreach(iter, entry0, newinfo->size) {
636 ret = check_entry_size_and_hooks(iter, newinfo, entry0,
637 entry0 + repl->size,
638 repl->hook_entry,
639 repl->underflow,
640 repl->valid_hooks);
641 if (ret != 0)
642 break;
643 ++i;
644 if (strcmp(arpt_get_target(iter)->u.user.name,
645 XT_ERROR_TARGET) == 0)
646 ++newinfo->stacksize;
647 }
648 duprintf("translate_table: ARPT_ENTRY_ITERATE gives %d\n", ret);
649 if (ret != 0)
650 return ret;
651
652 if (i != repl->num_entries) {
653 duprintf("translate_table: %u not %u entries\n",
654 i, repl->num_entries);
655 return -EINVAL;
656 }
657
658 /* Check hooks all assigned */
659 for (i = 0; i < NF_ARP_NUMHOOKS; i++) {
660 /* Only hooks which are valid */
661 if (!(repl->valid_hooks & (1 << i)))
662 continue;
663 if (newinfo->hook_entry[i] == 0xFFFFFFFF) {
664 duprintf("Invalid hook entry %u %u\n",
665 i, repl->hook_entry[i]);
666 return -EINVAL;
667 }
668 if (newinfo->underflow[i] == 0xFFFFFFFF) {
669 duprintf("Invalid underflow %u %u\n",
670 i, repl->underflow[i]);
671 return -EINVAL;
672 }
673 }
674
675 if (!mark_source_chains(newinfo, repl->valid_hooks, entry0)) {
676 duprintf("Looping hook\n");
677 return -ELOOP;
678 }
679
680 /* Finally, each sanity check must pass */
681 i = 0;
682 xt_entry_foreach(iter, entry0, newinfo->size) {
683 ret = find_check_entry(iter, repl->name, repl->size);
684 if (ret != 0)
685 break;
686 ++i;
687 }
688
689 if (ret != 0) {
690 xt_entry_foreach(iter, entry0, newinfo->size) {
691 if (i-- == 0)
692 break;
693 cleanup_entry(iter);
694 }
695 return ret;
696 }
697
698 /* And one copy for every other CPU */
699 for_each_possible_cpu(i) {
700 if (newinfo->entries[i] && newinfo->entries[i] != entry0)
701 memcpy(newinfo->entries[i], entry0, newinfo->size);
702 }
703
704 return ret;
705 }
706
707 static void get_counters(const struct xt_table_info *t,
708 struct xt_counters counters[])
709 {
710 struct arpt_entry *iter;
711 unsigned int cpu;
712 unsigned int i;
713 unsigned int curcpu = get_cpu();
714
715 /* Instead of clearing (by a previous call to memset())
716 * the counters and using adds, we set the counters
717 * with data used by 'current' CPU
718 *
719 * Bottom half has to be disabled to prevent deadlock
720 * if new softirq were to run and call ipt_do_table
721 */
722 local_bh_disable();
723 i = 0;
724 xt_entry_foreach(iter, t->entries[curcpu], t->size) {
725 SET_COUNTER(counters[i], iter->counters.bcnt,
726 iter->counters.pcnt);
727 ++i;
728 }
729 local_bh_enable();
730 /* Processing counters from other cpus, we can let bottom half enabled,
731 * (preemption is disabled)
732 */
733
734 for_each_possible_cpu(cpu) {
735 if (cpu == curcpu)
736 continue;
737 i = 0;
738 local_bh_disable();
739 xt_info_wrlock(cpu);
740 xt_entry_foreach(iter, t->entries[cpu], t->size) {
741 ADD_COUNTER(counters[i], iter->counters.bcnt,
742 iter->counters.pcnt);
743 ++i;
744 }
745 xt_info_wrunlock(cpu);
746 local_bh_enable();
747 }
748 put_cpu();
749 }
750
751 static struct xt_counters *alloc_counters(const struct xt_table *table)
752 {
753 unsigned int countersize;
754 struct xt_counters *counters;
755 const struct xt_table_info *private = table->private;
756
757 /* We need atomic snapshot of counters: rest doesn't change
758 * (other than comefrom, which userspace doesn't care
759 * about).
760 */
761 countersize = sizeof(struct xt_counters) * private->number;
762 counters = vmalloc(countersize);
763
764 if (counters == NULL)
765 return ERR_PTR(-ENOMEM);
766
767 get_counters(private, counters);
768
769 return counters;
770 }
771
772 static int copy_entries_to_user(unsigned int total_size,
773 const struct xt_table *table,
774 void __user *userptr)
775 {
776 unsigned int off, num;
777 const struct arpt_entry *e;
778 struct xt_counters *counters;
779 struct xt_table_info *private = table->private;
780 int ret = 0;
781 void *loc_cpu_entry;
782
783 counters = alloc_counters(table);
784 if (IS_ERR(counters))
785 return PTR_ERR(counters);
786
787 loc_cpu_entry = private->entries[raw_smp_processor_id()];
788 /* ... then copy entire thing ... */
789 if (copy_to_user(userptr, loc_cpu_entry, total_size) != 0) {
790 ret = -EFAULT;
791 goto free_counters;
792 }
793
794 /* FIXME: use iterator macros --RR */
795 /* ... then go back and fix counters and names */
796 for (off = 0, num = 0; off < total_size; off += e->next_offset, num++){
797 const struct xt_entry_target *t;
798
799 e = (struct arpt_entry *)(loc_cpu_entry + off);
800 if (copy_to_user(userptr + off
801 + offsetof(struct arpt_entry, counters),
802 &counters[num],
803 sizeof(counters[num])) != 0) {
804 ret = -EFAULT;
805 goto free_counters;
806 }
807
808 t = arpt_get_target_c(e);
809 if (copy_to_user(userptr + off + e->target_offset
810 + offsetof(struct xt_entry_target,
811 u.user.name),
812 t->u.kernel.target->name,
813 strlen(t->u.kernel.target->name)+1) != 0) {
814 ret = -EFAULT;
815 goto free_counters;
816 }
817 }
818
819 free_counters:
820 vfree(counters);
821 return ret;
822 }
823
824 #ifdef CONFIG_COMPAT
825 static void compat_standard_from_user(void *dst, const void *src)
826 {
827 int v = *(compat_int_t *)src;
828
829 if (v > 0)
830 v += xt_compat_calc_jump(NFPROTO_ARP, v);
831 memcpy(dst, &v, sizeof(v));
832 }
833
834 static int compat_standard_to_user(void __user *dst, const void *src)
835 {
836 compat_int_t cv = *(int *)src;
837
838 if (cv > 0)
839 cv -= xt_compat_calc_jump(NFPROTO_ARP, cv);
840 return copy_to_user(dst, &cv, sizeof(cv)) ? -EFAULT : 0;
841 }
842
843 static int compat_calc_entry(const struct arpt_entry *e,
844 const struct xt_table_info *info,
845 const void *base, struct xt_table_info *newinfo)
846 {
847 const struct xt_entry_target *t;
848 unsigned int entry_offset;
849 int off, i, ret;
850
851 off = sizeof(struct arpt_entry) - sizeof(struct compat_arpt_entry);
852 entry_offset = (void *)e - base;
853
854 t = arpt_get_target_c(e);
855 off += xt_compat_target_offset(t->u.kernel.target);
856 newinfo->size -= off;
857 ret = xt_compat_add_offset(NFPROTO_ARP, entry_offset, off);
858 if (ret)
859 return ret;
860
861 for (i = 0; i < NF_ARP_NUMHOOKS; i++) {
862 if (info->hook_entry[i] &&
863 (e < (struct arpt_entry *)(base + info->hook_entry[i])))
864 newinfo->hook_entry[i] -= off;
865 if (info->underflow[i] &&
866 (e < (struct arpt_entry *)(base + info->underflow[i])))
867 newinfo->underflow[i] -= off;
868 }
869 return 0;
870 }
871
872 static int compat_table_info(const struct xt_table_info *info,
873 struct xt_table_info *newinfo)
874 {
875 struct arpt_entry *iter;
876 void *loc_cpu_entry;
877 int ret;
878
879 if (!newinfo || !info)
880 return -EINVAL;
881
882 /* we dont care about newinfo->entries[] */
883 memcpy(newinfo, info, offsetof(struct xt_table_info, entries));
884 newinfo->initial_entries = 0;
885 loc_cpu_entry = info->entries[raw_smp_processor_id()];
886 xt_entry_foreach(iter, loc_cpu_entry, info->size) {
887 ret = compat_calc_entry(iter, info, loc_cpu_entry, newinfo);
888 if (ret != 0)
889 return ret;
890 }
891 return 0;
892 }
893 #endif
894
895 static int get_info(struct net *net, void __user *user,
896 const int *len, int compat)
897 {
898 char name[XT_TABLE_MAXNAMELEN];
899 struct xt_table *t;
900 int ret;
901
902 if (*len != sizeof(struct arpt_getinfo)) {
903 duprintf("length %u != %Zu\n", *len,
904 sizeof(struct arpt_getinfo));
905 return -EINVAL;
906 }
907
908 if (copy_from_user(name, user, sizeof(name)) != 0)
909 return -EFAULT;
910
911 name[XT_TABLE_MAXNAMELEN-1] = '\0';
912 #ifdef CONFIG_COMPAT
913 if (compat)
914 xt_compat_lock(NFPROTO_ARP);
915 #endif
916 t = try_then_request_module(xt_find_table_lock(net, NFPROTO_ARP, name),
917 "arptable_%s", name);
918 if (t && !IS_ERR(t)) {
919 struct arpt_getinfo info;
920 const struct xt_table_info *private = t->private;
921 #ifdef CONFIG_COMPAT
922 struct xt_table_info tmp;
923
924 if (compat) {
925 ret = compat_table_info(private, &tmp);
926 xt_compat_flush_offsets(NFPROTO_ARP);
927 private = &tmp;
928 }
929 #endif
930 memset(&info, 0, sizeof(info));
931 info.valid_hooks = t->valid_hooks;
932 memcpy(info.hook_entry, private->hook_entry,
933 sizeof(info.hook_entry));
934 memcpy(info.underflow, private->underflow,
935 sizeof(info.underflow));
936 info.num_entries = private->number;
937 info.size = private->size;
938 strcpy(info.name, name);
939
940 if (copy_to_user(user, &info, *len) != 0)
941 ret = -EFAULT;
942 else
943 ret = 0;
944 xt_table_unlock(t);
945 module_put(t->me);
946 } else
947 ret = t ? PTR_ERR(t) : -ENOENT;
948 #ifdef CONFIG_COMPAT
949 if (compat)
950 xt_compat_unlock(NFPROTO_ARP);
951 #endif
952 return ret;
953 }
954
955 static int get_entries(struct net *net, struct arpt_get_entries __user *uptr,
956 const int *len)
957 {
958 int ret;
959 struct arpt_get_entries get;
960 struct xt_table *t;
961
962 if (*len < sizeof(get)) {
963 duprintf("get_entries: %u < %Zu\n", *len, sizeof(get));
964 return -EINVAL;
965 }
966 if (copy_from_user(&get, uptr, sizeof(get)) != 0)
967 return -EFAULT;
968 if (*len != sizeof(struct arpt_get_entries) + get.size) {
969 duprintf("get_entries: %u != %Zu\n", *len,
970 sizeof(struct arpt_get_entries) + get.size);
971 return -EINVAL;
972 }
973
974 t = xt_find_table_lock(net, NFPROTO_ARP, get.name);
975 if (t && !IS_ERR(t)) {
976 const struct xt_table_info *private = t->private;
977
978 duprintf("t->private->number = %u\n",
979 private->number);
980 if (get.size == private->size)
981 ret = copy_entries_to_user(private->size,
982 t, uptr->entrytable);
983 else {
984 duprintf("get_entries: I've got %u not %u!\n",
985 private->size, get.size);
986 ret = -EAGAIN;
987 }
988 module_put(t->me);
989 xt_table_unlock(t);
990 } else
991 ret = t ? PTR_ERR(t) : -ENOENT;
992
993 return ret;
994 }
995
996 static int __do_replace(struct net *net, const char *name,
997 unsigned int valid_hooks,
998 struct xt_table_info *newinfo,
999 unsigned int num_counters,
1000 void __user *counters_ptr)
1001 {
1002 int ret;
1003 struct xt_table *t;
1004 struct xt_table_info *oldinfo;
1005 struct xt_counters *counters;
1006 void *loc_cpu_old_entry;
1007 struct arpt_entry *iter;
1008
1009 ret = 0;
1010 counters = vmalloc(num_counters * sizeof(struct xt_counters));
1011 if (!counters) {
1012 ret = -ENOMEM;
1013 goto out;
1014 }
1015
1016 t = try_then_request_module(xt_find_table_lock(net, NFPROTO_ARP, name),
1017 "arptable_%s", name);
1018 if (!t || IS_ERR(t)) {
1019 ret = t ? PTR_ERR(t) : -ENOENT;
1020 goto free_newinfo_counters_untrans;
1021 }
1022
1023 /* You lied! */
1024 if (valid_hooks != t->valid_hooks) {
1025 duprintf("Valid hook crap: %08X vs %08X\n",
1026 valid_hooks, t->valid_hooks);
1027 ret = -EINVAL;
1028 goto put_module;
1029 }
1030
1031 oldinfo = xt_replace_table(t, num_counters, newinfo, &ret);
1032 if (!oldinfo)
1033 goto put_module;
1034
1035 /* Update module usage count based on number of rules */
1036 duprintf("do_replace: oldnum=%u, initnum=%u, newnum=%u\n",
1037 oldinfo->number, oldinfo->initial_entries, newinfo->number);
1038 if ((oldinfo->number > oldinfo->initial_entries) ||
1039 (newinfo->number <= oldinfo->initial_entries))
1040 module_put(t->me);
1041 if ((oldinfo->number > oldinfo->initial_entries) &&
1042 (newinfo->number <= oldinfo->initial_entries))
1043 module_put(t->me);
1044
1045 /* Get the old counters, and synchronize with replace */
1046 get_counters(oldinfo, counters);
1047
1048 /* Decrease module usage counts and free resource */
1049 loc_cpu_old_entry = oldinfo->entries[raw_smp_processor_id()];
1050 xt_entry_foreach(iter, loc_cpu_old_entry, oldinfo->size)
1051 cleanup_entry(iter);
1052
1053 xt_free_table_info(oldinfo);
1054 if (copy_to_user(counters_ptr, counters,
1055 sizeof(struct xt_counters) * num_counters) != 0)
1056 ret = -EFAULT;
1057 vfree(counters);
1058 xt_table_unlock(t);
1059 return ret;
1060
1061 put_module:
1062 module_put(t->me);
1063 xt_table_unlock(t);
1064 free_newinfo_counters_untrans:
1065 vfree(counters);
1066 out:
1067 return ret;
1068 }
1069
1070 static int do_replace(struct net *net, const void __user *user,
1071 unsigned int len)
1072 {
1073 int ret;
1074 struct arpt_replace tmp;
1075 struct xt_table_info *newinfo;
1076 void *loc_cpu_entry;
1077 struct arpt_entry *iter;
1078
1079 if (copy_from_user(&tmp, user, sizeof(tmp)) != 0)
1080 return -EFAULT;
1081
1082 /* overflow check */
1083 if (tmp.num_counters >= INT_MAX / sizeof(struct xt_counters))
1084 return -ENOMEM;
1085
1086 newinfo = xt_alloc_table_info(tmp.size);
1087 if (!newinfo)
1088 return -ENOMEM;
1089
1090 /* choose the copy that is on our node/cpu */
1091 loc_cpu_entry = newinfo->entries[raw_smp_processor_id()];
1092 if (copy_from_user(loc_cpu_entry, user + sizeof(tmp),
1093 tmp.size) != 0) {
1094 ret = -EFAULT;
1095 goto free_newinfo;
1096 }
1097
1098 ret = translate_table(newinfo, loc_cpu_entry, &tmp);
1099 if (ret != 0)
1100 goto free_newinfo;
1101
1102 duprintf("arp_tables: Translated table\n");
1103
1104 ret = __do_replace(net, tmp.name, tmp.valid_hooks, newinfo,
1105 tmp.num_counters, tmp.counters);
1106 if (ret)
1107 goto free_newinfo_untrans;
1108 return 0;
1109
1110 free_newinfo_untrans:
1111 xt_entry_foreach(iter, loc_cpu_entry, newinfo->size)
1112 cleanup_entry(iter);
1113 free_newinfo:
1114 xt_free_table_info(newinfo);
1115 return ret;
1116 }
1117
1118 static int do_add_counters(struct net *net, const void __user *user,
1119 unsigned int len, int compat)
1120 {
1121 unsigned int i, curcpu;
1122 struct xt_counters_info tmp;
1123 struct xt_counters *paddc;
1124 unsigned int num_counters;
1125 const char *name;
1126 int size;
1127 void *ptmp;
1128 struct xt_table *t;
1129 const struct xt_table_info *private;
1130 int ret = 0;
1131 void *loc_cpu_entry;
1132 struct arpt_entry *iter;
1133 #ifdef CONFIG_COMPAT
1134 struct compat_xt_counters_info compat_tmp;
1135
1136 if (compat) {
1137 ptmp = &compat_tmp;
1138 size = sizeof(struct compat_xt_counters_info);
1139 } else
1140 #endif
1141 {
1142 ptmp = &tmp;
1143 size = sizeof(struct xt_counters_info);
1144 }
1145
1146 if (copy_from_user(ptmp, user, size) != 0)
1147 return -EFAULT;
1148
1149 #ifdef CONFIG_COMPAT
1150 if (compat) {
1151 num_counters = compat_tmp.num_counters;
1152 name = compat_tmp.name;
1153 } else
1154 #endif
1155 {
1156 num_counters = tmp.num_counters;
1157 name = tmp.name;
1158 }
1159
1160 if (len != size + num_counters * sizeof(struct xt_counters))
1161 return -EINVAL;
1162
1163 paddc = vmalloc(len - size);
1164 if (!paddc)
1165 return -ENOMEM;
1166
1167 if (copy_from_user(paddc, user + size, len - size) != 0) {
1168 ret = -EFAULT;
1169 goto free;
1170 }
1171
1172 t = xt_find_table_lock(net, NFPROTO_ARP, name);
1173 if (!t || IS_ERR(t)) {
1174 ret = t ? PTR_ERR(t) : -ENOENT;
1175 goto free;
1176 }
1177
1178 local_bh_disable();
1179 private = t->private;
1180 if (private->number != num_counters) {
1181 ret = -EINVAL;
1182 goto unlock_up_free;
1183 }
1184
1185 i = 0;
1186 /* Choose the copy that is on our node */
1187 curcpu = smp_processor_id();
1188 loc_cpu_entry = private->entries[curcpu];
1189 xt_info_wrlock(curcpu);
1190 xt_entry_foreach(iter, loc_cpu_entry, private->size) {
1191 ADD_COUNTER(iter->counters, paddc[i].bcnt, paddc[i].pcnt);
1192 ++i;
1193 }
1194 xt_info_wrunlock(curcpu);
1195 unlock_up_free:
1196 local_bh_enable();
1197 xt_table_unlock(t);
1198 module_put(t->me);
1199 free:
1200 vfree(paddc);
1201
1202 return ret;
1203 }
1204
1205 #ifdef CONFIG_COMPAT
1206 static inline void compat_release_entry(struct compat_arpt_entry *e)
1207 {
1208 struct xt_entry_target *t;
1209
1210 t = compat_arpt_get_target(e);
1211 module_put(t->u.kernel.target->me);
1212 }
1213
1214 static inline int
1215 check_compat_entry_size_and_hooks(struct compat_arpt_entry *e,
1216 struct xt_table_info *newinfo,
1217 unsigned int *size,
1218 const unsigned char *base,
1219 const unsigned char *limit,
1220 const unsigned int *hook_entries,
1221 const unsigned int *underflows,
1222 const char *name)
1223 {
1224 struct xt_entry_target *t;
1225 struct xt_target *target;
1226 unsigned int entry_offset;
1227 int ret, off, h;
1228
1229 duprintf("check_compat_entry_size_and_hooks %p\n", e);
1230 if ((unsigned long)e % __alignof__(struct compat_arpt_entry) != 0 ||
1231 (unsigned char *)e + sizeof(struct compat_arpt_entry) >= limit) {
1232 duprintf("Bad offset %p, limit = %p\n", e, limit);
1233 return -EINVAL;
1234 }
1235
1236 if (e->next_offset < sizeof(struct compat_arpt_entry) +
1237 sizeof(struct compat_xt_entry_target)) {
1238 duprintf("checking: element %p size %u\n",
1239 e, e->next_offset);
1240 return -EINVAL;
1241 }
1242
1243 /* For purposes of check_entry casting the compat entry is fine */
1244 ret = check_entry((struct arpt_entry *)e, name);
1245 if (ret)
1246 return ret;
1247
1248 off = sizeof(struct arpt_entry) - sizeof(struct compat_arpt_entry);
1249 entry_offset = (void *)e - (void *)base;
1250
1251 t = compat_arpt_get_target(e);
1252 target = xt_request_find_target(NFPROTO_ARP, t->u.user.name,
1253 t->u.user.revision);
1254 if (IS_ERR(target)) {
1255 duprintf("check_compat_entry_size_and_hooks: `%s' not found\n",
1256 t->u.user.name);
1257 ret = PTR_ERR(target);
1258 goto out;
1259 }
1260 t->u.kernel.target = target;
1261
1262 off += xt_compat_target_offset(target);
1263 *size += off;
1264 ret = xt_compat_add_offset(NFPROTO_ARP, entry_offset, off);
1265 if (ret)
1266 goto release_target;
1267
1268 /* Check hooks & underflows */
1269 for (h = 0; h < NF_ARP_NUMHOOKS; h++) {
1270 if ((unsigned char *)e - base == hook_entries[h])
1271 newinfo->hook_entry[h] = hook_entries[h];
1272 if ((unsigned char *)e - base == underflows[h])
1273 newinfo->underflow[h] = underflows[h];
1274 }
1275
1276 /* Clear counters and comefrom */
1277 memset(&e->counters, 0, sizeof(e->counters));
1278 e->comefrom = 0;
1279 return 0;
1280
1281 release_target:
1282 module_put(t->u.kernel.target->me);
1283 out:
1284 return ret;
1285 }
1286
1287 static int
1288 compat_copy_entry_from_user(struct compat_arpt_entry *e, void **dstptr,
1289 unsigned int *size, const char *name,
1290 struct xt_table_info *newinfo, unsigned char *base)
1291 {
1292 struct xt_entry_target *t;
1293 struct xt_target *target;
1294 struct arpt_entry *de;
1295 unsigned int origsize;
1296 int ret, h;
1297
1298 ret = 0;
1299 origsize = *size;
1300 de = (struct arpt_entry *)*dstptr;
1301 memcpy(de, e, sizeof(struct arpt_entry));
1302 memcpy(&de->counters, &e->counters, sizeof(e->counters));
1303
1304 *dstptr += sizeof(struct arpt_entry);
1305 *size += sizeof(struct arpt_entry) - sizeof(struct compat_arpt_entry);
1306
1307 de->target_offset = e->target_offset - (origsize - *size);
1308 t = compat_arpt_get_target(e);
1309 target = t->u.kernel.target;
1310 xt_compat_target_from_user(t, dstptr, size);
1311
1312 de->next_offset = e->next_offset - (origsize - *size);
1313 for (h = 0; h < NF_ARP_NUMHOOKS; h++) {
1314 if ((unsigned char *)de - base < newinfo->hook_entry[h])
1315 newinfo->hook_entry[h] -= origsize - *size;
1316 if ((unsigned char *)de - base < newinfo->underflow[h])
1317 newinfo->underflow[h] -= origsize - *size;
1318 }
1319 return ret;
1320 }
1321
1322 static int translate_compat_table(const char *name,
1323 unsigned int valid_hooks,
1324 struct xt_table_info **pinfo,
1325 void **pentry0,
1326 unsigned int total_size,
1327 unsigned int number,
1328 unsigned int *hook_entries,
1329 unsigned int *underflows)
1330 {
1331 unsigned int i, j;
1332 struct xt_table_info *newinfo, *info;
1333 void *pos, *entry0, *entry1;
1334 struct compat_arpt_entry *iter0;
1335 struct arpt_entry *iter1;
1336 unsigned int size;
1337 int ret = 0;
1338
1339 info = *pinfo;
1340 entry0 = *pentry0;
1341 size = total_size;
1342 info->number = number;
1343
1344 /* Init all hooks to impossible value. */
1345 for (i = 0; i < NF_ARP_NUMHOOKS; i++) {
1346 info->hook_entry[i] = 0xFFFFFFFF;
1347 info->underflow[i] = 0xFFFFFFFF;
1348 }
1349
1350 duprintf("translate_compat_table: size %u\n", info->size);
1351 j = 0;
1352 xt_compat_lock(NFPROTO_ARP);
1353 /* Walk through entries, checking offsets. */
1354 xt_entry_foreach(iter0, entry0, total_size) {
1355 ret = check_compat_entry_size_and_hooks(iter0, info, &size,
1356 entry0,
1357 entry0 + total_size,
1358 hook_entries,
1359 underflows,
1360 name);
1361 if (ret != 0)
1362 goto out_unlock;
1363 ++j;
1364 }
1365
1366 ret = -EINVAL;
1367 if (j != number) {
1368 duprintf("translate_compat_table: %u not %u entries\n",
1369 j, number);
1370 goto out_unlock;
1371 }
1372
1373 /* Check hooks all assigned */
1374 for (i = 0; i < NF_ARP_NUMHOOKS; i++) {
1375 /* Only hooks which are valid */
1376 if (!(valid_hooks & (1 << i)))
1377 continue;
1378 if (info->hook_entry[i] == 0xFFFFFFFF) {
1379 duprintf("Invalid hook entry %u %u\n",
1380 i, hook_entries[i]);
1381 goto out_unlock;
1382 }
1383 if (info->underflow[i] == 0xFFFFFFFF) {
1384 duprintf("Invalid underflow %u %u\n",
1385 i, underflows[i]);
1386 goto out_unlock;
1387 }
1388 }
1389
1390 ret = -ENOMEM;
1391 newinfo = xt_alloc_table_info(size);
1392 if (!newinfo)
1393 goto out_unlock;
1394
1395 newinfo->number = number;
1396 for (i = 0; i < NF_ARP_NUMHOOKS; i++) {
1397 newinfo->hook_entry[i] = info->hook_entry[i];
1398 newinfo->underflow[i] = info->underflow[i];
1399 }
1400 entry1 = newinfo->entries[raw_smp_processor_id()];
1401 pos = entry1;
1402 size = total_size;
1403 xt_entry_foreach(iter0, entry0, total_size) {
1404 ret = compat_copy_entry_from_user(iter0, &pos, &size,
1405 name, newinfo, entry1);
1406 if (ret != 0)
1407 break;
1408 }
1409 xt_compat_flush_offsets(NFPROTO_ARP);
1410 xt_compat_unlock(NFPROTO_ARP);
1411 if (ret)
1412 goto free_newinfo;
1413
1414 ret = -ELOOP;
1415 if (!mark_source_chains(newinfo, valid_hooks, entry1))
1416 goto free_newinfo;
1417
1418 i = 0;
1419 xt_entry_foreach(iter1, entry1, newinfo->size) {
1420 ret = check_target(iter1, name);
1421 if (ret != 0)
1422 break;
1423 ++i;
1424 if (strcmp(arpt_get_target(iter1)->u.user.name,
1425 XT_ERROR_TARGET) == 0)
1426 ++newinfo->stacksize;
1427 }
1428 if (ret) {
1429 /*
1430 * The first i matches need cleanup_entry (calls ->destroy)
1431 * because they had called ->check already. The other j-i
1432 * entries need only release.
1433 */
1434 int skip = i;
1435 j -= i;
1436 xt_entry_foreach(iter0, entry0, newinfo->size) {
1437 if (skip-- > 0)
1438 continue;
1439 if (j-- == 0)
1440 break;
1441 compat_release_entry(iter0);
1442 }
1443 xt_entry_foreach(iter1, entry1, newinfo->size) {
1444 if (i-- == 0)
1445 break;
1446 cleanup_entry(iter1);
1447 }
1448 xt_free_table_info(newinfo);
1449 return ret;
1450 }
1451
1452 /* And one copy for every other CPU */
1453 for_each_possible_cpu(i)
1454 if (newinfo->entries[i] && newinfo->entries[i] != entry1)
1455 memcpy(newinfo->entries[i], entry1, newinfo->size);
1456
1457 *pinfo = newinfo;
1458 *pentry0 = entry1;
1459 xt_free_table_info(info);
1460 return 0;
1461
1462 free_newinfo:
1463 xt_free_table_info(newinfo);
1464 out:
1465 xt_entry_foreach(iter0, entry0, total_size) {
1466 if (j-- == 0)
1467 break;
1468 compat_release_entry(iter0);
1469 }
1470 return ret;
1471 out_unlock:
1472 xt_compat_flush_offsets(NFPROTO_ARP);
1473 xt_compat_unlock(NFPROTO_ARP);
1474 goto out;
1475 }
1476
1477 struct compat_arpt_replace {
1478 char name[XT_TABLE_MAXNAMELEN];
1479 u32 valid_hooks;
1480 u32 num_entries;
1481 u32 size;
1482 u32 hook_entry[NF_ARP_NUMHOOKS];
1483 u32 underflow[NF_ARP_NUMHOOKS];
1484 u32 num_counters;
1485 compat_uptr_t counters;
1486 struct compat_arpt_entry entries[0];
1487 };
1488
1489 static int compat_do_replace(struct net *net, void __user *user,
1490 unsigned int len)
1491 {
1492 int ret;
1493 struct compat_arpt_replace tmp;
1494 struct xt_table_info *newinfo;
1495 void *loc_cpu_entry;
1496 struct arpt_entry *iter;
1497
1498 if (copy_from_user(&tmp, user, sizeof(tmp)) != 0)
1499 return -EFAULT;
1500
1501 /* overflow check */
1502 if (tmp.size >= INT_MAX / num_possible_cpus())
1503 return -ENOMEM;
1504 if (tmp.num_counters >= INT_MAX / sizeof(struct xt_counters))
1505 return -ENOMEM;
1506
1507 newinfo = xt_alloc_table_info(tmp.size);
1508 if (!newinfo)
1509 return -ENOMEM;
1510
1511 /* choose the copy that is on our node/cpu */
1512 loc_cpu_entry = newinfo->entries[raw_smp_processor_id()];
1513 if (copy_from_user(loc_cpu_entry, user + sizeof(tmp), tmp.size) != 0) {
1514 ret = -EFAULT;
1515 goto free_newinfo;
1516 }
1517
1518 ret = translate_compat_table(tmp.name, tmp.valid_hooks,
1519 &newinfo, &loc_cpu_entry, tmp.size,
1520 tmp.num_entries, tmp.hook_entry,
1521 tmp.underflow);
1522 if (ret != 0)
1523 goto free_newinfo;
1524
1525 duprintf("compat_do_replace: Translated table\n");
1526
1527 ret = __do_replace(net, tmp.name, tmp.valid_hooks, newinfo,
1528 tmp.num_counters, compat_ptr(tmp.counters));
1529 if (ret)
1530 goto free_newinfo_untrans;
1531 return 0;
1532
1533 free_newinfo_untrans:
1534 xt_entry_foreach(iter, loc_cpu_entry, newinfo->size)
1535 cleanup_entry(iter);
1536 free_newinfo:
1537 xt_free_table_info(newinfo);
1538 return ret;
1539 }
1540
1541 static int compat_do_arpt_set_ctl(struct sock *sk, int cmd, void __user *user,
1542 unsigned int len)
1543 {
1544 int ret;
1545
1546 if (!capable(CAP_NET_ADMIN))
1547 return -EPERM;
1548
1549 switch (cmd) {
1550 case ARPT_SO_SET_REPLACE:
1551 ret = compat_do_replace(sock_net(sk), user, len);
1552 break;
1553
1554 case ARPT_SO_SET_ADD_COUNTERS:
1555 ret = do_add_counters(sock_net(sk), user, len, 1);
1556 break;
1557
1558 default:
1559 duprintf("do_arpt_set_ctl: unknown request %i\n", cmd);
1560 ret = -EINVAL;
1561 }
1562
1563 return ret;
1564 }
1565
1566 static int compat_copy_entry_to_user(struct arpt_entry *e, void __user **dstptr,
1567 compat_uint_t *size,
1568 struct xt_counters *counters,
1569 unsigned int i)
1570 {
1571 struct xt_entry_target *t;
1572 struct compat_arpt_entry __user *ce;
1573 u_int16_t target_offset, next_offset;
1574 compat_uint_t origsize;
1575 int ret;
1576
1577 origsize = *size;
1578 ce = (struct compat_arpt_entry __user *)*dstptr;
1579 if (copy_to_user(ce, e, sizeof(struct arpt_entry)) != 0 ||
1580 copy_to_user(&ce->counters, &counters[i],
1581 sizeof(counters[i])) != 0)
1582 return -EFAULT;
1583
1584 *dstptr += sizeof(struct compat_arpt_entry);
1585 *size -= sizeof(struct arpt_entry) - sizeof(struct compat_arpt_entry);
1586
1587 target_offset = e->target_offset - (origsize - *size);
1588
1589 t = arpt_get_target(e);
1590 ret = xt_compat_target_to_user(t, dstptr, size);
1591 if (ret)
1592 return ret;
1593 next_offset = e->next_offset - (origsize - *size);
1594 if (put_user(target_offset, &ce->target_offset) != 0 ||
1595 put_user(next_offset, &ce->next_offset) != 0)
1596 return -EFAULT;
1597 return 0;
1598 }
1599
1600 static int compat_copy_entries_to_user(unsigned int total_size,
1601 struct xt_table *table,
1602 void __user *userptr)
1603 {
1604 struct xt_counters *counters;
1605 const struct xt_table_info *private = table->private;
1606 void __user *pos;
1607 unsigned int size;
1608 int ret = 0;
1609 void *loc_cpu_entry;
1610 unsigned int i = 0;
1611 struct arpt_entry *iter;
1612
1613 counters = alloc_counters(table);
1614 if (IS_ERR(counters))
1615 return PTR_ERR(counters);
1616
1617 /* choose the copy on our node/cpu */
1618 loc_cpu_entry = private->entries[raw_smp_processor_id()];
1619 pos = userptr;
1620 size = total_size;
1621 xt_entry_foreach(iter, loc_cpu_entry, total_size) {
1622 ret = compat_copy_entry_to_user(iter, &pos,
1623 &size, counters, i++);
1624 if (ret != 0)
1625 break;
1626 }
1627 vfree(counters);
1628 return ret;
1629 }
1630
1631 struct compat_arpt_get_entries {
1632 char name[XT_TABLE_MAXNAMELEN];
1633 compat_uint_t size;
1634 struct compat_arpt_entry entrytable[0];
1635 };
1636
1637 static int compat_get_entries(struct net *net,
1638 struct compat_arpt_get_entries __user *uptr,
1639 int *len)
1640 {
1641 int ret;
1642 struct compat_arpt_get_entries get;
1643 struct xt_table *t;
1644
1645 if (*len < sizeof(get)) {
1646 duprintf("compat_get_entries: %u < %zu\n", *len, sizeof(get));
1647 return -EINVAL;
1648 }
1649 if (copy_from_user(&get, uptr, sizeof(get)) != 0)
1650 return -EFAULT;
1651 if (*len != sizeof(struct compat_arpt_get_entries) + get.size) {
1652 duprintf("compat_get_entries: %u != %zu\n",
1653 *len, sizeof(get) + get.size);
1654 return -EINVAL;
1655 }
1656
1657 xt_compat_lock(NFPROTO_ARP);
1658 t = xt_find_table_lock(net, NFPROTO_ARP, get.name);
1659 if (t && !IS_ERR(t)) {
1660 const struct xt_table_info *private = t->private;
1661 struct xt_table_info info;
1662
1663 duprintf("t->private->number = %u\n", private->number);
1664 ret = compat_table_info(private, &info);
1665 if (!ret && get.size == info.size) {
1666 ret = compat_copy_entries_to_user(private->size,
1667 t, uptr->entrytable);
1668 } else if (!ret) {
1669 duprintf("compat_get_entries: I've got %u not %u!\n",
1670 private->size, get.size);
1671 ret = -EAGAIN;
1672 }
1673 xt_compat_flush_offsets(NFPROTO_ARP);
1674 module_put(t->me);
1675 xt_table_unlock(t);
1676 } else
1677 ret = t ? PTR_ERR(t) : -ENOENT;
1678
1679 xt_compat_unlock(NFPROTO_ARP);
1680 return ret;
1681 }
1682
1683 static int do_arpt_get_ctl(struct sock *, int, void __user *, int *);
1684
1685 static int compat_do_arpt_get_ctl(struct sock *sk, int cmd, void __user *user,
1686 int *len)
1687 {
1688 int ret;
1689
1690 if (!capable(CAP_NET_ADMIN))
1691 return -EPERM;
1692
1693 switch (cmd) {
1694 case ARPT_SO_GET_INFO:
1695 ret = get_info(sock_net(sk), user, len, 1);
1696 break;
1697 case ARPT_SO_GET_ENTRIES:
1698 ret = compat_get_entries(sock_net(sk), user, len);
1699 break;
1700 default:
1701 ret = do_arpt_get_ctl(sk, cmd, user, len);
1702 }
1703 return ret;
1704 }
1705 #endif
1706
1707 static int do_arpt_set_ctl(struct sock *sk, int cmd, void __user *user, unsigned int len)
1708 {
1709 int ret;
1710
1711 if (!capable(CAP_NET_ADMIN))
1712 return -EPERM;
1713
1714 switch (cmd) {
1715 case ARPT_SO_SET_REPLACE:
1716 ret = do_replace(sock_net(sk), user, len);
1717 break;
1718
1719 case ARPT_SO_SET_ADD_COUNTERS:
1720 ret = do_add_counters(sock_net(sk), user, len, 0);
1721 break;
1722
1723 default:
1724 duprintf("do_arpt_set_ctl: unknown request %i\n", cmd);
1725 ret = -EINVAL;
1726 }
1727
1728 return ret;
1729 }
1730
1731 static int do_arpt_get_ctl(struct sock *sk, int cmd, void __user *user, int *len)
1732 {
1733 int ret;
1734
1735 if (!capable(CAP_NET_ADMIN))
1736 return -EPERM;
1737
1738 switch (cmd) {
1739 case ARPT_SO_GET_INFO:
1740 ret = get_info(sock_net(sk), user, len, 0);
1741 break;
1742
1743 case ARPT_SO_GET_ENTRIES:
1744 ret = get_entries(sock_net(sk), user, len);
1745 break;
1746
1747 case ARPT_SO_GET_REVISION_TARGET: {
1748 struct xt_get_revision rev;
1749
1750 if (*len != sizeof(rev)) {
1751 ret = -EINVAL;
1752 break;
1753 }
1754 if (copy_from_user(&rev, user, sizeof(rev)) != 0) {
1755 ret = -EFAULT;
1756 break;
1757 }
1758
1759 try_then_request_module(xt_find_revision(NFPROTO_ARP, rev.name,
1760 rev.revision, 1, &ret),
1761 "arpt_%s", rev.name);
1762 break;
1763 }
1764
1765 default:
1766 duprintf("do_arpt_get_ctl: unknown request %i\n", cmd);
1767 ret = -EINVAL;
1768 }
1769
1770 return ret;
1771 }
1772
1773 struct xt_table *arpt_register_table(struct net *net,
1774 const struct xt_table *table,
1775 const struct arpt_replace *repl)
1776 {
1777 int ret;
1778 struct xt_table_info *newinfo;
1779 struct xt_table_info bootstrap = {0};
1780 void *loc_cpu_entry;
1781 struct xt_table *new_table;
1782
1783 newinfo = xt_alloc_table_info(repl->size);
1784 if (!newinfo) {
1785 ret = -ENOMEM;
1786 goto out;
1787 }
1788
1789 /* choose the copy on our node/cpu */
1790 loc_cpu_entry = newinfo->entries[raw_smp_processor_id()];
1791 memcpy(loc_cpu_entry, repl->entries, repl->size);
1792
1793 ret = translate_table(newinfo, loc_cpu_entry, repl);
1794 duprintf("arpt_register_table: translate table gives %d\n", ret);
1795 if (ret != 0)
1796 goto out_free;
1797
1798 new_table = xt_register_table(net, table, &bootstrap, newinfo);
1799 if (IS_ERR(new_table)) {
1800 ret = PTR_ERR(new_table);
1801 goto out_free;
1802 }
1803 return new_table;
1804
1805 out_free:
1806 xt_free_table_info(newinfo);
1807 out:
1808 return ERR_PTR(ret);
1809 }
1810
1811 void arpt_unregister_table(struct xt_table *table)
1812 {
1813 struct xt_table_info *private;
1814 void *loc_cpu_entry;
1815 struct module *table_owner = table->me;
1816 struct arpt_entry *iter;
1817
1818 private = xt_unregister_table(table);
1819
1820 /* Decrease module usage counts and free resources */
1821 loc_cpu_entry = private->entries[raw_smp_processor_id()];
1822 xt_entry_foreach(iter, loc_cpu_entry, private->size)
1823 cleanup_entry(iter);
1824 if (private->number > private->initial_entries)
1825 module_put(table_owner);
1826 xt_free_table_info(private);
1827 }
1828
1829 /* The built-in targets: standard (NULL) and error. */
1830 static struct xt_target arpt_builtin_tg[] __read_mostly = {
1831 {
1832 .name = XT_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 .name = XT_ERROR_TARGET,
1843 .target = arpt_error,
1844 .targetsize = XT_FUNCTION_MAXNAMELEN,
1845 .family = NFPROTO_ARP,
1846 },
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_targets(arpt_builtin_tg, ARRAY_SIZE(arpt_builtin_tg));
1891 if (ret < 0)
1892 goto err2;
1893
1894 /* Register setsockopt */
1895 ret = nf_register_sockopt(&arpt_sockopts);
1896 if (ret < 0)
1897 goto err4;
1898
1899 printk(KERN_INFO "arp_tables: (C) 2002 David S. Miller\n");
1900 return 0;
1901
1902 err4:
1903 xt_unregister_targets(arpt_builtin_tg, ARRAY_SIZE(arpt_builtin_tg));
1904 err2:
1905 unregister_pernet_subsys(&arp_tables_net_ops);
1906 err1:
1907 return ret;
1908 }
1909
1910 static void __exit arp_tables_fini(void)
1911 {
1912 nf_unregister_sockopt(&arpt_sockopts);
1913 xt_unregister_targets(arpt_builtin_tg, ARRAY_SIZE(arpt_builtin_tg));
1914 unregister_pernet_subsys(&arp_tables_net_ops);
1915 }
1916
1917 EXPORT_SYMBOL(arpt_register_table);
1918 EXPORT_SYMBOL(arpt_unregister_table);
1919 EXPORT_SYMBOL(arpt_do_table);
1920
1921 module_init(arp_tables_init);
1922 module_exit(arp_tables_fini);
kernel source for telekom puls (alcatel/mediatek)