Commit | Line | Data |
---|---|---|
1da177e4 LT |
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) | |
f229f6ce | 9 | * Copyright (C) 2006-2009 Patrick McHardy <kaber@trash.net> |
1da177e4 LT |
10 | * |
11 | */ | |
90e7d4ab | 12 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
1da177e4 LT |
13 | #include <linux/kernel.h> |
14 | #include <linux/skbuff.h> | |
15 | #include <linux/netdevice.h> | |
4fc268d2 | 16 | #include <linux/capability.h> |
1da177e4 LT |
17 | #include <linux/if_arp.h> |
18 | #include <linux/kmod.h> | |
19 | #include <linux/vmalloc.h> | |
20 | #include <linux/proc_fs.h> | |
21 | #include <linux/module.h> | |
22 | #include <linux/init.h> | |
57b47a53 | 23 | #include <linux/mutex.h> |
d6a2ba07 PM |
24 | #include <linux/err.h> |
25 | #include <net/compat.h> | |
79df341a | 26 | #include <net/sock.h> |
d6a2ba07 | 27 | #include <asm/uaccess.h> |
1da177e4 | 28 | |
2e4e6a17 | 29 | #include <linux/netfilter/x_tables.h> |
1da177e4 | 30 | #include <linux/netfilter_arp/arp_tables.h> |
e3eaa991 | 31 | #include "../../netfilter/xt_repldata.h" |
1da177e4 LT |
32 | |
33 | MODULE_LICENSE("GPL"); | |
34 | MODULE_AUTHOR("David S. Miller <davem@redhat.com>"); | |
35 | MODULE_DESCRIPTION("arptables core"); | |
36 | ||
37 | /*#define DEBUG_ARP_TABLES*/ | |
38 | /*#define DEBUG_ARP_TABLES_USER*/ | |
39 | ||
40 | #ifdef DEBUG_ARP_TABLES | |
41 | #define dprintf(format, args...) printk(format , ## args) | |
42 | #else | |
43 | #define dprintf(format, args...) | |
44 | #endif | |
45 | ||
46 | #ifdef DEBUG_ARP_TABLES_USER | |
47 | #define duprintf(format, args...) printk(format , ## args) | |
48 | #else | |
49 | #define duprintf(format, args...) | |
50 | #endif | |
51 | ||
52 | #ifdef CONFIG_NETFILTER_DEBUG | |
af567603 | 53 | #define ARP_NF_ASSERT(x) WARN_ON(!(x)) |
1da177e4 LT |
54 | #else |
55 | #define ARP_NF_ASSERT(x) | |
56 | #endif | |
1da177e4 | 57 | |
e3eaa991 JE |
58 | void *arpt_alloc_initial_table(const struct xt_table *info) |
59 | { | |
60 | return xt_alloc_initial_table(arpt, ARPT); | |
61 | } | |
62 | EXPORT_SYMBOL_GPL(arpt_alloc_initial_table); | |
63 | ||
1da177e4 | 64 | static inline int arp_devaddr_compare(const struct arpt_devaddr_info *ap, |
5452e425 | 65 | const char *hdr_addr, int len) |
1da177e4 LT |
66 | { |
67 | int i, ret; | |
68 | ||
69 | if (len > ARPT_DEV_ADDR_LEN_MAX) | |
70 | len = ARPT_DEV_ADDR_LEN_MAX; | |
71 | ||
72 | ret = 0; | |
73 | for (i = 0; i < len; i++) | |
74 | ret |= (hdr_addr[i] ^ ap->addr[i]) & ap->mask[i]; | |
75 | ||
a02cec21 | 76 | return ret != 0; |
1da177e4 LT |
77 | } |
78 | ||
ddc214c4 | 79 | /* |
25985edc | 80 | * Unfortunately, _b and _mask are not aligned to an int (or long int) |
ddc214c4 | 81 | * Some arches dont care, unrolling the loop is a win on them. |
35c7f6de | 82 | * For other arches, we only have a 16bit alignement. |
ddc214c4 ED |
83 | */ |
84 | static unsigned long ifname_compare(const char *_a, const char *_b, const char *_mask) | |
85 | { | |
86 | #ifdef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS | |
b8dfe498 | 87 | unsigned long ret = ifname_compare_aligned(_a, _b, _mask); |
ddc214c4 ED |
88 | #else |
89 | unsigned long ret = 0; | |
35c7f6de ED |
90 | const u16 *a = (const u16 *)_a; |
91 | const u16 *b = (const u16 *)_b; | |
92 | const u16 *mask = (const u16 *)_mask; | |
ddc214c4 ED |
93 | int i; |
94 | ||
35c7f6de ED |
95 | for (i = 0; i < IFNAMSIZ/sizeof(u16); i++) |
96 | ret |= (a[i] ^ b[i]) & mask[i]; | |
ddc214c4 ED |
97 | #endif |
98 | return ret; | |
99 | } | |
100 | ||
1da177e4 LT |
101 | /* Returns whether packet matches rule or not. */ |
102 | static inline int arp_packet_match(const struct arphdr *arphdr, | |
103 | struct net_device *dev, | |
104 | const char *indev, | |
105 | const char *outdev, | |
106 | const struct arpt_arp *arpinfo) | |
107 | { | |
5452e425 JE |
108 | const char *arpptr = (char *)(arphdr + 1); |
109 | const char *src_devaddr, *tgt_devaddr; | |
59b8bfd8 | 110 | __be32 src_ipaddr, tgt_ipaddr; |
ddc214c4 | 111 | long ret; |
1da177e4 | 112 | |
e79ec50b | 113 | #define FWINV(bool, invflg) ((bool) ^ !!(arpinfo->invflags & (invflg))) |
1da177e4 LT |
114 | |
115 | if (FWINV((arphdr->ar_op & arpinfo->arpop_mask) != arpinfo->arpop, | |
116 | ARPT_INV_ARPOP)) { | |
117 | dprintf("ARP operation field mismatch.\n"); | |
118 | dprintf("ar_op: %04x info->arpop: %04x info->arpop_mask: %04x\n", | |
119 | arphdr->ar_op, arpinfo->arpop, arpinfo->arpop_mask); | |
120 | return 0; | |
121 | } | |
122 | ||
123 | if (FWINV((arphdr->ar_hrd & arpinfo->arhrd_mask) != arpinfo->arhrd, | |
124 | ARPT_INV_ARPHRD)) { | |
125 | dprintf("ARP hardware address format mismatch.\n"); | |
126 | dprintf("ar_hrd: %04x info->arhrd: %04x info->arhrd_mask: %04x\n", | |
127 | arphdr->ar_hrd, arpinfo->arhrd, arpinfo->arhrd_mask); | |
128 | return 0; | |
129 | } | |
130 | ||
131 | if (FWINV((arphdr->ar_pro & arpinfo->arpro_mask) != arpinfo->arpro, | |
132 | ARPT_INV_ARPPRO)) { | |
133 | dprintf("ARP protocol address format mismatch.\n"); | |
134 | dprintf("ar_pro: %04x info->arpro: %04x info->arpro_mask: %04x\n", | |
135 | arphdr->ar_pro, arpinfo->arpro, arpinfo->arpro_mask); | |
136 | return 0; | |
137 | } | |
138 | ||
139 | if (FWINV((arphdr->ar_hln & arpinfo->arhln_mask) != arpinfo->arhln, | |
140 | ARPT_INV_ARPHLN)) { | |
141 | dprintf("ARP hardware address length mismatch.\n"); | |
142 | dprintf("ar_hln: %02x info->arhln: %02x info->arhln_mask: %02x\n", | |
143 | arphdr->ar_hln, arpinfo->arhln, arpinfo->arhln_mask); | |
144 | return 0; | |
145 | } | |
146 | ||
147 | src_devaddr = arpptr; | |
148 | arpptr += dev->addr_len; | |
149 | memcpy(&src_ipaddr, arpptr, sizeof(u32)); | |
150 | arpptr += sizeof(u32); | |
151 | tgt_devaddr = arpptr; | |
152 | arpptr += dev->addr_len; | |
153 | memcpy(&tgt_ipaddr, arpptr, sizeof(u32)); | |
154 | ||
155 | if (FWINV(arp_devaddr_compare(&arpinfo->src_devaddr, src_devaddr, dev->addr_len), | |
156 | ARPT_INV_SRCDEVADDR) || | |
157 | FWINV(arp_devaddr_compare(&arpinfo->tgt_devaddr, tgt_devaddr, dev->addr_len), | |
158 | ARPT_INV_TGTDEVADDR)) { | |
159 | dprintf("Source or target device address mismatch.\n"); | |
160 | ||
161 | return 0; | |
162 | } | |
163 | ||
164 | if (FWINV((src_ipaddr & arpinfo->smsk.s_addr) != arpinfo->src.s_addr, | |
165 | ARPT_INV_SRCIP) || | |
166 | FWINV(((tgt_ipaddr & arpinfo->tmsk.s_addr) != arpinfo->tgt.s_addr), | |
167 | ARPT_INV_TGTIP)) { | |
168 | dprintf("Source or target IP address mismatch.\n"); | |
169 | ||
cffee385 HH |
170 | dprintf("SRC: %pI4. Mask: %pI4. Target: %pI4.%s\n", |
171 | &src_ipaddr, | |
172 | &arpinfo->smsk.s_addr, | |
173 | &arpinfo->src.s_addr, | |
1da177e4 | 174 | arpinfo->invflags & ARPT_INV_SRCIP ? " (INV)" : ""); |
cffee385 HH |
175 | dprintf("TGT: %pI4 Mask: %pI4 Target: %pI4.%s\n", |
176 | &tgt_ipaddr, | |
177 | &arpinfo->tmsk.s_addr, | |
178 | &arpinfo->tgt.s_addr, | |
1da177e4 LT |
179 | arpinfo->invflags & ARPT_INV_TGTIP ? " (INV)" : ""); |
180 | return 0; | |
181 | } | |
182 | ||
183 | /* Look for ifname matches. */ | |
ddc214c4 | 184 | ret = ifname_compare(indev, arpinfo->iniface, arpinfo->iniface_mask); |
1da177e4 LT |
185 | |
186 | if (FWINV(ret != 0, ARPT_INV_VIA_IN)) { | |
187 | dprintf("VIA in mismatch (%s vs %s).%s\n", | |
188 | indev, arpinfo->iniface, | |
189 | arpinfo->invflags&ARPT_INV_VIA_IN ?" (INV)":""); | |
190 | return 0; | |
191 | } | |
192 | ||
ddc214c4 | 193 | ret = ifname_compare(outdev, arpinfo->outiface, arpinfo->outiface_mask); |
1da177e4 LT |
194 | |
195 | if (FWINV(ret != 0, ARPT_INV_VIA_OUT)) { | |
196 | dprintf("VIA out mismatch (%s vs %s).%s\n", | |
197 | outdev, arpinfo->outiface, | |
198 | arpinfo->invflags&ARPT_INV_VIA_OUT ?" (INV)":""); | |
199 | return 0; | |
200 | } | |
201 | ||
202 | return 1; | |
e79ec50b | 203 | #undef FWINV |
1da177e4 LT |
204 | } |
205 | ||
206 | static inline int arp_checkentry(const struct arpt_arp *arp) | |
207 | { | |
208 | if (arp->flags & ~ARPT_F_MASK) { | |
209 | duprintf("Unknown flag bits set: %08X\n", | |
210 | arp->flags & ~ARPT_F_MASK); | |
211 | return 0; | |
212 | } | |
213 | if (arp->invflags & ~ARPT_INV_MASK) { | |
214 | duprintf("Unknown invflag bits set: %08X\n", | |
215 | arp->invflags & ~ARPT_INV_MASK); | |
216 | return 0; | |
217 | } | |
218 | ||
219 | return 1; | |
220 | } | |
221 | ||
7eb35586 | 222 | static unsigned int |
4b560b44 | 223 | arpt_error(struct sk_buff *skb, const struct xt_action_param *par) |
1da177e4 | 224 | { |
e87cc472 JP |
225 | net_err_ratelimited("arp_tables: error: '%s'\n", |
226 | (const char *)par->targinfo); | |
1da177e4 LT |
227 | |
228 | return NF_DROP; | |
229 | } | |
230 | ||
87a2e70d | 231 | static inline const struct xt_entry_target * |
d5d1baa1 JE |
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) | |
1da177e4 LT |
239 | { |
240 | return (struct arpt_entry *)(base + offset); | |
241 | } | |
242 | ||
98e86403 JE |
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 | ||
3db05fea | 249 | unsigned int arpt_do_table(struct sk_buff *skb, |
1da177e4 LT |
250 | unsigned int hook, |
251 | const struct net_device *in, | |
252 | const struct net_device *out, | |
4abff077 | 253 | struct xt_table *table) |
1da177e4 | 254 | { |
ddc214c4 | 255 | static const char nulldevname[IFNAMSIZ] __attribute__((aligned(sizeof(long)))); |
1da177e4 | 256 | unsigned int verdict = NF_DROP; |
5452e425 | 257 | const struct arphdr *arp; |
1da177e4 LT |
258 | struct arpt_entry *e, *back; |
259 | const char *indev, *outdev; | |
260 | void *table_base; | |
5452e425 | 261 | const struct xt_table_info *private; |
de74c169 | 262 | struct xt_action_param acpar; |
7f5c6d4f | 263 | unsigned int addend; |
1da177e4 | 264 | |
988b7050 | 265 | if (!pskb_may_pull(skb, arp_hdr_len(skb->dev))) |
1da177e4 LT |
266 | return NF_DROP; |
267 | ||
268 | indev = in ? in->name : nulldevname; | |
269 | outdev = out ? out->name : nulldevname; | |
270 | ||
7f5c6d4f ED |
271 | local_bh_disable(); |
272 | addend = xt_write_recseq_begin(); | |
942e4a2b SH |
273 | private = table->private; |
274 | table_base = private->entries[smp_processor_id()]; | |
78454473 | 275 | |
2e4e6a17 HW |
276 | e = get_entry(table_base, private->hook_entry[hook]); |
277 | back = get_entry(table_base, private->underflow[hook]); | |
1da177e4 | 278 | |
de74c169 JE |
279 | acpar.in = in; |
280 | acpar.out = out; | |
281 | acpar.hooknum = hook; | |
282 | acpar.family = NFPROTO_ARP; | |
b4ba2611 | 283 | acpar.hotdrop = false; |
7eb35586 | 284 | |
3db05fea | 285 | arp = arp_hdr(skb); |
1da177e4 | 286 | do { |
87a2e70d | 287 | const struct xt_entry_target *t; |
a1ff4ac8 JE |
288 | |
289 | if (!arp_packet_match(arp, skb->dev, indev, outdev, &e->arp)) { | |
290 | e = arpt_next_entry(e); | |
291 | continue; | |
292 | } | |
293 | ||
f667009e | 294 | ADD_COUNTER(e->counters, arp_hdr_len(skb->dev), 1); |
1da177e4 | 295 | |
d5d1baa1 | 296 | t = arpt_get_target_c(e); |
a1ff4ac8 JE |
297 | |
298 | /* Standard target? */ | |
299 | if (!t->u.kernel.target->target) { | |
300 | int v; | |
301 | ||
87a2e70d | 302 | v = ((struct xt_standard_target *)t)->verdict; |
a1ff4ac8 JE |
303 | if (v < 0) { |
304 | /* Pop from stack? */ | |
243bf6e2 | 305 | if (v != XT_RETURN) { |
95c96174 | 306 | verdict = (unsigned int)(-v) - 1; |
1da177e4 | 307 | break; |
a1ff4ac8 JE |
308 | } |
309 | e = back; | |
310 | back = get_entry(table_base, back->comefrom); | |
311 | continue; | |
1da177e4 | 312 | } |
a1ff4ac8 JE |
313 | if (table_base + v |
314 | != arpt_next_entry(e)) { | |
315 | /* Save old back ptr in next entry */ | |
316 | struct arpt_entry *next = arpt_next_entry(e); | |
317 | next->comefrom = (void *)back - table_base; | |
318 | ||
319 | /* set back pointer to next entry */ | |
320 | back = next; | |
321 | } | |
322 | ||
323 | e = get_entry(table_base, v); | |
7a6b1c46 | 324 | continue; |
1da177e4 | 325 | } |
7a6b1c46 JE |
326 | |
327 | /* Targets which reenter must return | |
328 | * abs. verdicts | |
329 | */ | |
de74c169 JE |
330 | acpar.target = t->u.kernel.target; |
331 | acpar.targinfo = t->data; | |
332 | verdict = t->u.kernel.target->target(skb, &acpar); | |
7a6b1c46 JE |
333 | |
334 | /* Target might have changed stuff. */ | |
335 | arp = arp_hdr(skb); | |
336 | ||
243bf6e2 | 337 | if (verdict == XT_CONTINUE) |
7a6b1c46 JE |
338 | e = arpt_next_entry(e); |
339 | else | |
340 | /* Verdict */ | |
341 | break; | |
b4ba2611 | 342 | } while (!acpar.hotdrop); |
7f5c6d4f ED |
343 | xt_write_recseq_end(addend); |
344 | local_bh_enable(); | |
1da177e4 | 345 | |
b4ba2611 | 346 | if (acpar.hotdrop) |
1da177e4 LT |
347 | return NF_DROP; |
348 | else | |
349 | return verdict; | |
350 | } | |
351 | ||
1da177e4 | 352 | /* All zeroes == unconditional rule. */ |
47901dc2 | 353 | static inline bool unconditional(const struct arpt_arp *arp) |
1da177e4 | 354 | { |
47901dc2 | 355 | static const struct arpt_arp uncond; |
1da177e4 | 356 | |
47901dc2 | 357 | return memcmp(arp, &uncond, sizeof(uncond)) == 0; |
1da177e4 LT |
358 | } |
359 | ||
360 | /* Figures out from what hook each rule can be called: returns 0 if | |
361 | * there are loops. Puts hook bitmask in comefrom. | |
362 | */ | |
d5d1baa1 | 363 | static int mark_source_chains(const struct xt_table_info *newinfo, |
31836064 | 364 | unsigned int valid_hooks, void *entry0) |
1da177e4 LT |
365 | { |
366 | unsigned int hook; | |
367 | ||
368 | /* No recursion; use packet counter to save back ptrs (reset | |
369 | * to 0 as we leave), and comefrom to save source hook bitmask. | |
370 | */ | |
371 | for (hook = 0; hook < NF_ARP_NUMHOOKS; hook++) { | |
372 | unsigned int pos = newinfo->hook_entry[hook]; | |
373 | struct arpt_entry *e | |
31836064 | 374 | = (struct arpt_entry *)(entry0 + pos); |
1da177e4 LT |
375 | |
376 | if (!(valid_hooks & (1 << hook))) | |
377 | continue; | |
378 | ||
379 | /* Set initial back pointer. */ | |
380 | e->counters.pcnt = pos; | |
381 | ||
382 | for (;;) { | |
87a2e70d | 383 | const struct xt_standard_target *t |
d5d1baa1 | 384 | = (void *)arpt_get_target_c(e); |
e1b4b9f3 | 385 | int visited = e->comefrom & (1 << hook); |
1da177e4 LT |
386 | |
387 | if (e->comefrom & (1 << NF_ARP_NUMHOOKS)) { | |
654d0fbd | 388 | pr_notice("arptables: loop hook %u pos %u %08X.\n", |
1da177e4 LT |
389 | hook, pos, e->comefrom); |
390 | return 0; | |
391 | } | |
392 | e->comefrom | |
393 | |= ((1 << hook) | (1 << NF_ARP_NUMHOOKS)); | |
394 | ||
395 | /* Unconditional return/END. */ | |
3666ed1c JP |
396 | if ((e->target_offset == sizeof(struct arpt_entry) && |
397 | (strcmp(t->target.u.user.name, | |
243bf6e2 | 398 | XT_STANDARD_TARGET) == 0) && |
3666ed1c JP |
399 | t->verdict < 0 && unconditional(&e->arp)) || |
400 | visited) { | |
1da177e4 LT |
401 | unsigned int oldpos, size; |
402 | ||
1f9352ae | 403 | if ((strcmp(t->target.u.user.name, |
243bf6e2 | 404 | XT_STANDARD_TARGET) == 0) && |
1f9352ae | 405 | t->verdict < -NF_MAX_VERDICT - 1) { |
74c9c0c1 DM |
406 | duprintf("mark_source_chains: bad " |
407 | "negative verdict (%i)\n", | |
408 | t->verdict); | |
409 | return 0; | |
410 | } | |
411 | ||
1da177e4 LT |
412 | /* Return: backtrack through the last |
413 | * big jump. | |
414 | */ | |
415 | do { | |
416 | e->comefrom ^= (1<<NF_ARP_NUMHOOKS); | |
417 | oldpos = pos; | |
418 | pos = e->counters.pcnt; | |
419 | e->counters.pcnt = 0; | |
420 | ||
421 | /* We're at the start. */ | |
422 | if (pos == oldpos) | |
423 | goto next; | |
424 | ||
425 | e = (struct arpt_entry *) | |
31836064 | 426 | (entry0 + pos); |
1da177e4 LT |
427 | } while (oldpos == pos + e->next_offset); |
428 | ||
429 | /* Move along one */ | |
430 | size = e->next_offset; | |
431 | e = (struct arpt_entry *) | |
31836064 | 432 | (entry0 + pos + size); |
1da177e4 LT |
433 | e->counters.pcnt = pos; |
434 | pos += size; | |
435 | } else { | |
436 | int newpos = t->verdict; | |
437 | ||
438 | if (strcmp(t->target.u.user.name, | |
243bf6e2 | 439 | XT_STANDARD_TARGET) == 0 && |
3666ed1c | 440 | newpos >= 0) { |
74c9c0c1 DM |
441 | if (newpos > newinfo->size - |
442 | sizeof(struct arpt_entry)) { | |
443 | duprintf("mark_source_chains: " | |
444 | "bad verdict (%i)\n", | |
445 | newpos); | |
446 | return 0; | |
447 | } | |
448 | ||
1da177e4 LT |
449 | /* This a jump; chase it. */ |
450 | duprintf("Jump rule %u -> %u\n", | |
451 | pos, newpos); | |
452 | } else { | |
453 | /* ... this is a fallthru */ | |
454 | newpos = pos + e->next_offset; | |
455 | } | |
456 | e = (struct arpt_entry *) | |
31836064 | 457 | (entry0 + newpos); |
1da177e4 LT |
458 | e->counters.pcnt = pos; |
459 | pos = newpos; | |
460 | } | |
461 | } | |
462 | next: | |
463 | duprintf("Finished chain %u\n", hook); | |
464 | } | |
465 | return 1; | |
466 | } | |
467 | ||
0608074c | 468 | static inline int check_entry(const struct arpt_entry *e) |
1da177e4 | 469 | { |
87a2e70d | 470 | const struct xt_entry_target *t; |
1da177e4 | 471 | |
0608074c | 472 | if (!arp_checkentry(&e->arp)) |
1da177e4 | 473 | return -EINVAL; |
1da177e4 | 474 | |
87a2e70d | 475 | if (e->target_offset + sizeof(struct xt_entry_target) > e->next_offset) |
590bdf7f DM |
476 | return -EINVAL; |
477 | ||
d5d1baa1 | 478 | t = arpt_get_target_c(e); |
590bdf7f DM |
479 | if (e->target_offset + t->u.target_size > e->next_offset) |
480 | return -EINVAL; | |
481 | ||
fb5b6095 PM |
482 | return 0; |
483 | } | |
484 | ||
485 | static inline int check_target(struct arpt_entry *e, const char *name) | |
486 | { | |
87a2e70d | 487 | struct xt_entry_target *t = arpt_get_target(e); |
fb5b6095 | 488 | int ret; |
af5d6dc2 JE |
489 | struct xt_tgchk_param par = { |
490 | .table = name, | |
491 | .entryinfo = e, | |
492 | .target = t->u.kernel.target, | |
493 | .targinfo = t->data, | |
494 | .hook_mask = e->comefrom, | |
916a917d | 495 | .family = NFPROTO_ARP, |
af5d6dc2 JE |
496 | }; |
497 | ||
916a917d | 498 | ret = xt_check_target(&par, t->u.target_size - sizeof(*t), 0, false); |
367c6790 | 499 | if (ret < 0) { |
fb5b6095 PM |
500 | duprintf("arp_tables: check failed for `%s'.\n", |
501 | t->u.kernel.target->name); | |
367c6790 | 502 | return ret; |
fb5b6095 | 503 | } |
367c6790 | 504 | return 0; |
fb5b6095 PM |
505 | } |
506 | ||
507 | static inline int | |
0559518b | 508 | find_check_entry(struct arpt_entry *e, const char *name, unsigned int size) |
fb5b6095 | 509 | { |
87a2e70d | 510 | struct xt_entry_target *t; |
95eea855 | 511 | struct xt_target *target; |
fb5b6095 PM |
512 | int ret; |
513 | ||
fb5b6095 | 514 | t = arpt_get_target(e); |
d2a7b6ba JE |
515 | target = xt_request_find_target(NFPROTO_ARP, t->u.user.name, |
516 | t->u.user.revision); | |
517 | if (IS_ERR(target)) { | |
fb5b6095 | 518 | duprintf("find_check_entry: `%s' not found\n", t->u.user.name); |
d2a7b6ba | 519 | ret = PTR_ERR(target); |
1da177e4 LT |
520 | goto out; |
521 | } | |
1da177e4 | 522 | t->u.kernel.target = target; |
1da177e4 | 523 | |
fb5b6095 | 524 | ret = check_target(e, name); |
3cdc7c95 PM |
525 | if (ret) |
526 | goto err; | |
1da177e4 | 527 | return 0; |
3cdc7c95 PM |
528 | err: |
529 | module_put(t->u.kernel.target->me); | |
1da177e4 LT |
530 | out: |
531 | return ret; | |
532 | } | |
533 | ||
d5d1baa1 | 534 | static bool check_underflow(const struct arpt_entry *e) |
e2fe35c1 | 535 | { |
87a2e70d | 536 | const struct xt_entry_target *t; |
e2fe35c1 JE |
537 | unsigned int verdict; |
538 | ||
539 | if (!unconditional(&e->arp)) | |
540 | return false; | |
d5d1baa1 | 541 | t = arpt_get_target_c(e); |
e2fe35c1 JE |
542 | if (strcmp(t->u.user.name, XT_STANDARD_TARGET) != 0) |
543 | return false; | |
87a2e70d | 544 | verdict = ((struct xt_standard_target *)t)->verdict; |
e2fe35c1 JE |
545 | verdict = -verdict - 1; |
546 | return verdict == NF_DROP || verdict == NF_ACCEPT; | |
547 | } | |
548 | ||
1da177e4 | 549 | static inline int check_entry_size_and_hooks(struct arpt_entry *e, |
2e4e6a17 | 550 | struct xt_table_info *newinfo, |
d5d1baa1 JE |
551 | const unsigned char *base, |
552 | const unsigned char *limit, | |
1da177e4 LT |
553 | const unsigned int *hook_entries, |
554 | const unsigned int *underflows, | |
0559518b | 555 | unsigned int valid_hooks) |
1da177e4 LT |
556 | { |
557 | unsigned int h; | |
0608074c | 558 | int err; |
1da177e4 | 559 | |
3666ed1c | 560 | if ((unsigned long)e % __alignof__(struct arpt_entry) != 0 || |
74afad87 FW |
561 | (unsigned char *)e + sizeof(struct arpt_entry) >= limit || |
562 | (unsigned char *)e + e->next_offset > limit) { | |
1da177e4 LT |
563 | duprintf("Bad offset %p\n", e); |
564 | return -EINVAL; | |
565 | } | |
566 | ||
567 | if (e->next_offset | |
87a2e70d | 568 | < sizeof(struct arpt_entry) + sizeof(struct xt_entry_target)) { |
1da177e4 LT |
569 | duprintf("checking: element %p size %u\n", |
570 | e, e->next_offset); | |
571 | return -EINVAL; | |
572 | } | |
573 | ||
0608074c FW |
574 | err = check_entry(e); |
575 | if (err) | |
576 | return err; | |
577 | ||
1da177e4 LT |
578 | /* Check hooks & underflows */ |
579 | for (h = 0; h < NF_ARP_NUMHOOKS; h++) { | |
a7d51738 JE |
580 | if (!(valid_hooks & (1 << h))) |
581 | continue; | |
1da177e4 LT |
582 | if ((unsigned char *)e - base == hook_entries[h]) |
583 | newinfo->hook_entry[h] = hook_entries[h]; | |
90e7d4ab | 584 | if ((unsigned char *)e - base == underflows[h]) { |
e2fe35c1 JE |
585 | if (!check_underflow(e)) { |
586 | pr_err("Underflows must be unconditional and " | |
587 | "use the STANDARD target with " | |
588 | "ACCEPT/DROP\n"); | |
90e7d4ab JE |
589 | return -EINVAL; |
590 | } | |
1da177e4 | 591 | newinfo->underflow[h] = underflows[h]; |
90e7d4ab | 592 | } |
1da177e4 LT |
593 | } |
594 | ||
1da177e4 | 595 | /* Clear counters and comefrom */ |
2e4e6a17 | 596 | e->counters = ((struct xt_counters) { 0, 0 }); |
1da177e4 | 597 | e->comefrom = 0; |
1da177e4 LT |
598 | return 0; |
599 | } | |
600 | ||
0559518b | 601 | static inline void cleanup_entry(struct arpt_entry *e) |
1da177e4 | 602 | { |
a2df1648 | 603 | struct xt_tgdtor_param par; |
87a2e70d | 604 | struct xt_entry_target *t; |
1da177e4 | 605 | |
1da177e4 | 606 | t = arpt_get_target(e); |
a2df1648 JE |
607 | par.target = t->u.kernel.target; |
608 | par.targinfo = t->data; | |
916a917d | 609 | par.family = NFPROTO_ARP; |
a2df1648 JE |
610 | if (par.target->destroy != NULL) |
611 | par.target->destroy(&par); | |
612 | module_put(par.target->me); | |
1da177e4 LT |
613 | } |
614 | ||
615 | /* Checks and translates the user-supplied table segment (held in | |
616 | * newinfo). | |
617 | */ | |
0f234214 JE |
618 | static int translate_table(struct xt_table_info *newinfo, void *entry0, |
619 | const struct arpt_replace *repl) | |
1da177e4 | 620 | { |
72b2b1dd | 621 | struct arpt_entry *iter; |
1da177e4 | 622 | unsigned int i; |
72b2b1dd | 623 | int ret = 0; |
1da177e4 | 624 | |
0f234214 JE |
625 | newinfo->size = repl->size; |
626 | newinfo->number = repl->num_entries; | |
1da177e4 LT |
627 | |
628 | /* Init all hooks to impossible value. */ | |
629 | for (i = 0; i < NF_ARP_NUMHOOKS; i++) { | |
630 | newinfo->hook_entry[i] = 0xFFFFFFFF; | |
631 | newinfo->underflow[i] = 0xFFFFFFFF; | |
632 | } | |
633 | ||
634 | duprintf("translate_table: size %u\n", newinfo->size); | |
635 | i = 0; | |
636 | ||
637 | /* Walk through entries, checking offsets. */ | |
72b2b1dd JE |
638 | xt_entry_foreach(iter, entry0, newinfo->size) { |
639 | ret = check_entry_size_and_hooks(iter, newinfo, entry0, | |
6b4ff2d7 JE |
640 | entry0 + repl->size, |
641 | repl->hook_entry, | |
642 | repl->underflow, | |
643 | repl->valid_hooks); | |
72b2b1dd JE |
644 | if (ret != 0) |
645 | break; | |
0559518b | 646 | ++i; |
f3c5c1bf JE |
647 | if (strcmp(arpt_get_target(iter)->u.user.name, |
648 | XT_ERROR_TARGET) == 0) | |
649 | ++newinfo->stacksize; | |
72b2b1dd | 650 | } |
1da177e4 LT |
651 | duprintf("translate_table: ARPT_ENTRY_ITERATE gives %d\n", ret); |
652 | if (ret != 0) | |
653 | return ret; | |
654 | ||
0f234214 | 655 | if (i != repl->num_entries) { |
1da177e4 | 656 | duprintf("translate_table: %u not %u entries\n", |
0f234214 | 657 | i, repl->num_entries); |
1da177e4 LT |
658 | return -EINVAL; |
659 | } | |
660 | ||
661 | /* Check hooks all assigned */ | |
662 | for (i = 0; i < NF_ARP_NUMHOOKS; i++) { | |
663 | /* Only hooks which are valid */ | |
0f234214 | 664 | if (!(repl->valid_hooks & (1 << i))) |
1da177e4 LT |
665 | continue; |
666 | if (newinfo->hook_entry[i] == 0xFFFFFFFF) { | |
667 | duprintf("Invalid hook entry %u %u\n", | |
0f234214 | 668 | i, repl->hook_entry[i]); |
1da177e4 LT |
669 | return -EINVAL; |
670 | } | |
671 | if (newinfo->underflow[i] == 0xFFFFFFFF) { | |
672 | duprintf("Invalid underflow %u %u\n", | |
0f234214 | 673 | i, repl->underflow[i]); |
1da177e4 LT |
674 | return -EINVAL; |
675 | } | |
676 | } | |
677 | ||
0f234214 | 678 | if (!mark_source_chains(newinfo, repl->valid_hooks, entry0)) { |
74c9c0c1 DM |
679 | duprintf("Looping hook\n"); |
680 | return -ELOOP; | |
681 | } | |
682 | ||
1da177e4 LT |
683 | /* Finally, each sanity check must pass */ |
684 | i = 0; | |
72b2b1dd | 685 | xt_entry_foreach(iter, entry0, newinfo->size) { |
0f234214 | 686 | ret = find_check_entry(iter, repl->name, repl->size); |
72b2b1dd JE |
687 | if (ret != 0) |
688 | break; | |
0559518b | 689 | ++i; |
72b2b1dd | 690 | } |
1da177e4 | 691 | |
74c9c0c1 | 692 | if (ret != 0) { |
0559518b JE |
693 | xt_entry_foreach(iter, entry0, newinfo->size) { |
694 | if (i-- == 0) | |
72b2b1dd | 695 | break; |
0559518b JE |
696 | cleanup_entry(iter); |
697 | } | |
74c9c0c1 | 698 | return ret; |
1da177e4 LT |
699 | } |
700 | ||
701 | /* And one copy for every other CPU */ | |
6f912042 | 702 | for_each_possible_cpu(i) { |
31836064 ED |
703 | if (newinfo->entries[i] && newinfo->entries[i] != entry0) |
704 | memcpy(newinfo->entries[i], entry0, newinfo->size); | |
1da177e4 LT |
705 | } |
706 | ||
707 | return ret; | |
708 | } | |
709 | ||
2e4e6a17 HW |
710 | static void get_counters(const struct xt_table_info *t, |
711 | struct xt_counters counters[]) | |
1da177e4 | 712 | { |
72b2b1dd | 713 | struct arpt_entry *iter; |
1da177e4 LT |
714 | unsigned int cpu; |
715 | unsigned int i; | |
716 | ||
6f912042 | 717 | for_each_possible_cpu(cpu) { |
7f5c6d4f | 718 | seqcount_t *s = &per_cpu(xt_recseq, cpu); |
83723d60 | 719 | |
1da177e4 | 720 | i = 0; |
0559518b | 721 | xt_entry_foreach(iter, t->entries[cpu], t->size) { |
83723d60 ED |
722 | u64 bcnt, pcnt; |
723 | unsigned int start; | |
724 | ||
725 | do { | |
7f5c6d4f | 726 | start = read_seqcount_begin(s); |
83723d60 ED |
727 | bcnt = iter->counters.bcnt; |
728 | pcnt = iter->counters.pcnt; | |
7f5c6d4f | 729 | } while (read_seqcount_retry(s, start)); |
83723d60 ED |
730 | |
731 | ADD_COUNTER(counters[i], bcnt, pcnt); | |
0559518b JE |
732 | ++i; |
733 | } | |
1da177e4 | 734 | } |
78454473 SH |
735 | } |
736 | ||
d5d1baa1 | 737 | static struct xt_counters *alloc_counters(const struct xt_table *table) |
1da177e4 | 738 | { |
27e2c26b | 739 | unsigned int countersize; |
2e4e6a17 | 740 | struct xt_counters *counters; |
d5d1baa1 | 741 | const struct xt_table_info *private = table->private; |
1da177e4 LT |
742 | |
743 | /* We need atomic snapshot of counters: rest doesn't change | |
744 | * (other than comefrom, which userspace doesn't care | |
745 | * about). | |
746 | */ | |
2e4e6a17 | 747 | countersize = sizeof(struct xt_counters) * private->number; |
83723d60 | 748 | counters = vzalloc(countersize); |
1da177e4 LT |
749 | |
750 | if (counters == NULL) | |
942e4a2b | 751 | return ERR_PTR(-ENOMEM); |
78454473 | 752 | |
942e4a2b | 753 | get_counters(private, counters); |
1da177e4 | 754 | |
27e2c26b PM |
755 | return counters; |
756 | } | |
757 | ||
758 | static int copy_entries_to_user(unsigned int total_size, | |
d5d1baa1 | 759 | const struct xt_table *table, |
27e2c26b PM |
760 | void __user *userptr) |
761 | { | |
762 | unsigned int off, num; | |
d5d1baa1 | 763 | const struct arpt_entry *e; |
27e2c26b | 764 | struct xt_counters *counters; |
4abff077 | 765 | struct xt_table_info *private = table->private; |
27e2c26b PM |
766 | int ret = 0; |
767 | void *loc_cpu_entry; | |
768 | ||
769 | counters = alloc_counters(table); | |
770 | if (IS_ERR(counters)) | |
771 | return PTR_ERR(counters); | |
772 | ||
2e4e6a17 | 773 | loc_cpu_entry = private->entries[raw_smp_processor_id()]; |
31836064 ED |
774 | /* ... then copy entire thing ... */ |
775 | if (copy_to_user(userptr, loc_cpu_entry, total_size) != 0) { | |
1da177e4 LT |
776 | ret = -EFAULT; |
777 | goto free_counters; | |
778 | } | |
779 | ||
780 | /* FIXME: use iterator macros --RR */ | |
781 | /* ... then go back and fix counters and names */ | |
782 | for (off = 0, num = 0; off < total_size; off += e->next_offset, num++){ | |
87a2e70d | 783 | const struct xt_entry_target *t; |
1da177e4 | 784 | |
31836064 | 785 | e = (struct arpt_entry *)(loc_cpu_entry + off); |
1da177e4 LT |
786 | if (copy_to_user(userptr + off |
787 | + offsetof(struct arpt_entry, counters), | |
788 | &counters[num], | |
789 | sizeof(counters[num])) != 0) { | |
790 | ret = -EFAULT; | |
791 | goto free_counters; | |
792 | } | |
793 | ||
d5d1baa1 | 794 | t = arpt_get_target_c(e); |
1da177e4 | 795 | if (copy_to_user(userptr + off + e->target_offset |
87a2e70d | 796 | + offsetof(struct xt_entry_target, |
1da177e4 LT |
797 | u.user.name), |
798 | t->u.kernel.target->name, | |
799 | strlen(t->u.kernel.target->name)+1) != 0) { | |
800 | ret = -EFAULT; | |
801 | goto free_counters; | |
802 | } | |
803 | } | |
804 | ||
805 | free_counters: | |
806 | vfree(counters); | |
807 | return ret; | |
808 | } | |
809 | ||
d6a2ba07 | 810 | #ifdef CONFIG_COMPAT |
739674fb | 811 | static void compat_standard_from_user(void *dst, const void *src) |
d6a2ba07 PM |
812 | { |
813 | int v = *(compat_int_t *)src; | |
814 | ||
815 | if (v > 0) | |
ee999d8b | 816 | v += xt_compat_calc_jump(NFPROTO_ARP, v); |
d6a2ba07 PM |
817 | memcpy(dst, &v, sizeof(v)); |
818 | } | |
819 | ||
739674fb | 820 | static int compat_standard_to_user(void __user *dst, const void *src) |
d6a2ba07 PM |
821 | { |
822 | compat_int_t cv = *(int *)src; | |
823 | ||
824 | if (cv > 0) | |
ee999d8b | 825 | cv -= xt_compat_calc_jump(NFPROTO_ARP, cv); |
d6a2ba07 PM |
826 | return copy_to_user(dst, &cv, sizeof(cv)) ? -EFAULT : 0; |
827 | } | |
828 | ||
d5d1baa1 | 829 | static int compat_calc_entry(const struct arpt_entry *e, |
d6a2ba07 | 830 | const struct xt_table_info *info, |
d5d1baa1 | 831 | const void *base, struct xt_table_info *newinfo) |
d6a2ba07 | 832 | { |
87a2e70d | 833 | const struct xt_entry_target *t; |
d6a2ba07 PM |
834 | unsigned int entry_offset; |
835 | int off, i, ret; | |
836 | ||
837 | off = sizeof(struct arpt_entry) - sizeof(struct compat_arpt_entry); | |
838 | entry_offset = (void *)e - base; | |
839 | ||
d5d1baa1 | 840 | t = arpt_get_target_c(e); |
d6a2ba07 PM |
841 | off += xt_compat_target_offset(t->u.kernel.target); |
842 | newinfo->size -= off; | |
ee999d8b | 843 | ret = xt_compat_add_offset(NFPROTO_ARP, entry_offset, off); |
d6a2ba07 PM |
844 | if (ret) |
845 | return ret; | |
846 | ||
847 | for (i = 0; i < NF_ARP_NUMHOOKS; i++) { | |
848 | if (info->hook_entry[i] && | |
849 | (e < (struct arpt_entry *)(base + info->hook_entry[i]))) | |
850 | newinfo->hook_entry[i] -= off; | |
851 | if (info->underflow[i] && | |
852 | (e < (struct arpt_entry *)(base + info->underflow[i]))) | |
853 | newinfo->underflow[i] -= off; | |
854 | } | |
855 | return 0; | |
856 | } | |
857 | ||
858 | static int compat_table_info(const struct xt_table_info *info, | |
859 | struct xt_table_info *newinfo) | |
860 | { | |
72b2b1dd | 861 | struct arpt_entry *iter; |
d6a2ba07 | 862 | void *loc_cpu_entry; |
0559518b | 863 | int ret; |
d6a2ba07 PM |
864 | |
865 | if (!newinfo || !info) | |
866 | return -EINVAL; | |
867 | ||
868 | /* we dont care about newinfo->entries[] */ | |
869 | memcpy(newinfo, info, offsetof(struct xt_table_info, entries)); | |
870 | newinfo->initial_entries = 0; | |
871 | loc_cpu_entry = info->entries[raw_smp_processor_id()]; | |
255d0dc3 | 872 | xt_compat_init_offsets(NFPROTO_ARP, info->number); |
72b2b1dd JE |
873 | xt_entry_foreach(iter, loc_cpu_entry, info->size) { |
874 | ret = compat_calc_entry(iter, info, loc_cpu_entry, newinfo); | |
875 | if (ret != 0) | |
0559518b | 876 | return ret; |
72b2b1dd | 877 | } |
0559518b | 878 | return 0; |
d6a2ba07 PM |
879 | } |
880 | #endif | |
881 | ||
d5d1baa1 JE |
882 | static int get_info(struct net *net, void __user *user, |
883 | const int *len, int compat) | |
41acd975 | 884 | { |
12b00c2c | 885 | char name[XT_TABLE_MAXNAMELEN]; |
4abff077 | 886 | struct xt_table *t; |
41acd975 PM |
887 | int ret; |
888 | ||
889 | if (*len != sizeof(struct arpt_getinfo)) { | |
890 | duprintf("length %u != %Zu\n", *len, | |
891 | sizeof(struct arpt_getinfo)); | |
892 | return -EINVAL; | |
893 | } | |
894 | ||
895 | if (copy_from_user(name, user, sizeof(name)) != 0) | |
896 | return -EFAULT; | |
897 | ||
12b00c2c | 898 | name[XT_TABLE_MAXNAMELEN-1] = '\0'; |
d6a2ba07 PM |
899 | #ifdef CONFIG_COMPAT |
900 | if (compat) | |
ee999d8b | 901 | xt_compat_lock(NFPROTO_ARP); |
d6a2ba07 | 902 | #endif |
ee999d8b | 903 | t = try_then_request_module(xt_find_table_lock(net, NFPROTO_ARP, name), |
41acd975 | 904 | "arptable_%s", name); |
0cc8d8df | 905 | if (!IS_ERR_OR_NULL(t)) { |
41acd975 | 906 | struct arpt_getinfo info; |
5452e425 | 907 | const struct xt_table_info *private = t->private; |
d6a2ba07 | 908 | #ifdef CONFIG_COMPAT |
14c7dbe0 AD |
909 | struct xt_table_info tmp; |
910 | ||
d6a2ba07 | 911 | if (compat) { |
d6a2ba07 | 912 | ret = compat_table_info(private, &tmp); |
ee999d8b | 913 | xt_compat_flush_offsets(NFPROTO_ARP); |
d6a2ba07 PM |
914 | private = &tmp; |
915 | } | |
916 | #endif | |
1a8b7a67 | 917 | memset(&info, 0, sizeof(info)); |
41acd975 PM |
918 | info.valid_hooks = t->valid_hooks; |
919 | memcpy(info.hook_entry, private->hook_entry, | |
920 | sizeof(info.hook_entry)); | |
921 | memcpy(info.underflow, private->underflow, | |
922 | sizeof(info.underflow)); | |
923 | info.num_entries = private->number; | |
924 | info.size = private->size; | |
925 | strcpy(info.name, name); | |
926 | ||
927 | if (copy_to_user(user, &info, *len) != 0) | |
928 | ret = -EFAULT; | |
929 | else | |
930 | ret = 0; | |
931 | xt_table_unlock(t); | |
932 | module_put(t->me); | |
933 | } else | |
934 | ret = t ? PTR_ERR(t) : -ENOENT; | |
d6a2ba07 PM |
935 | #ifdef CONFIG_COMPAT |
936 | if (compat) | |
ee999d8b | 937 | xt_compat_unlock(NFPROTO_ARP); |
d6a2ba07 | 938 | #endif |
41acd975 PM |
939 | return ret; |
940 | } | |
941 | ||
79df341a | 942 | static int get_entries(struct net *net, struct arpt_get_entries __user *uptr, |
d5d1baa1 | 943 | const int *len) |
1da177e4 LT |
944 | { |
945 | int ret; | |
11f6dff8 | 946 | struct arpt_get_entries get; |
4abff077 | 947 | struct xt_table *t; |
1da177e4 | 948 | |
11f6dff8 PM |
949 | if (*len < sizeof(get)) { |
950 | duprintf("get_entries: %u < %Zu\n", *len, sizeof(get)); | |
951 | return -EINVAL; | |
952 | } | |
953 | if (copy_from_user(&get, uptr, sizeof(get)) != 0) | |
954 | return -EFAULT; | |
955 | if (*len != sizeof(struct arpt_get_entries) + get.size) { | |
956 | duprintf("get_entries: %u != %Zu\n", *len, | |
957 | sizeof(struct arpt_get_entries) + get.size); | |
958 | return -EINVAL; | |
959 | } | |
960 | ||
ee999d8b | 961 | t = xt_find_table_lock(net, NFPROTO_ARP, get.name); |
0cc8d8df | 962 | if (!IS_ERR_OR_NULL(t)) { |
5452e425 JE |
963 | const struct xt_table_info *private = t->private; |
964 | ||
1da177e4 | 965 | duprintf("t->private->number = %u\n", |
2e4e6a17 | 966 | private->number); |
11f6dff8 | 967 | if (get.size == private->size) |
2e4e6a17 | 968 | ret = copy_entries_to_user(private->size, |
1da177e4 LT |
969 | t, uptr->entrytable); |
970 | else { | |
971 | duprintf("get_entries: I've got %u not %u!\n", | |
11f6dff8 | 972 | private->size, get.size); |
544473c1 | 973 | ret = -EAGAIN; |
1da177e4 | 974 | } |
6b7d31fc | 975 | module_put(t->me); |
2e4e6a17 | 976 | xt_table_unlock(t); |
1da177e4 | 977 | } else |
6b7d31fc | 978 | ret = t ? PTR_ERR(t) : -ENOENT; |
1da177e4 LT |
979 | |
980 | return ret; | |
981 | } | |
982 | ||
79df341a AD |
983 | static int __do_replace(struct net *net, const char *name, |
984 | unsigned int valid_hooks, | |
d6a2ba07 PM |
985 | struct xt_table_info *newinfo, |
986 | unsigned int num_counters, | |
987 | void __user *counters_ptr) | |
1da177e4 LT |
988 | { |
989 | int ret; | |
4abff077 | 990 | struct xt_table *t; |
d6a2ba07 | 991 | struct xt_table_info *oldinfo; |
2e4e6a17 | 992 | struct xt_counters *counters; |
d6a2ba07 | 993 | void *loc_cpu_old_entry; |
72b2b1dd | 994 | struct arpt_entry *iter; |
1da177e4 | 995 | |
d6a2ba07 | 996 | ret = 0; |
83723d60 | 997 | counters = vzalloc(num_counters * sizeof(struct xt_counters)); |
1da177e4 LT |
998 | if (!counters) { |
999 | ret = -ENOMEM; | |
d6a2ba07 | 1000 | goto out; |
1da177e4 | 1001 | } |
1da177e4 | 1002 | |
ee999d8b | 1003 | t = try_then_request_module(xt_find_table_lock(net, NFPROTO_ARP, name), |
d6a2ba07 | 1004 | "arptable_%s", name); |
0cc8d8df | 1005 | if (IS_ERR_OR_NULL(t)) { |
6b7d31fc | 1006 | ret = t ? PTR_ERR(t) : -ENOENT; |
1da177e4 | 1007 | goto free_newinfo_counters_untrans; |
6b7d31fc | 1008 | } |
1da177e4 LT |
1009 | |
1010 | /* You lied! */ | |
d6a2ba07 | 1011 | if (valid_hooks != t->valid_hooks) { |
1da177e4 | 1012 | duprintf("Valid hook crap: %08X vs %08X\n", |
d6a2ba07 | 1013 | valid_hooks, t->valid_hooks); |
1da177e4 | 1014 | ret = -EINVAL; |
6b7d31fc | 1015 | goto put_module; |
1da177e4 LT |
1016 | } |
1017 | ||
d6a2ba07 | 1018 | oldinfo = xt_replace_table(t, num_counters, newinfo, &ret); |
1da177e4 LT |
1019 | if (!oldinfo) |
1020 | goto put_module; | |
1021 | ||
1022 | /* Update module usage count based on number of rules */ | |
1023 | duprintf("do_replace: oldnum=%u, initnum=%u, newnum=%u\n", | |
1024 | oldinfo->number, oldinfo->initial_entries, newinfo->number); | |
e905a9ed YH |
1025 | if ((oldinfo->number > oldinfo->initial_entries) || |
1026 | (newinfo->number <= oldinfo->initial_entries)) | |
1da177e4 LT |
1027 | module_put(t->me); |
1028 | if ((oldinfo->number > oldinfo->initial_entries) && | |
1029 | (newinfo->number <= oldinfo->initial_entries)) | |
1030 | module_put(t->me); | |
1031 | ||
942e4a2b | 1032 | /* Get the old counters, and synchronize with replace */ |
1da177e4 | 1033 | get_counters(oldinfo, counters); |
942e4a2b | 1034 | |
1da177e4 | 1035 | /* Decrease module usage counts and free resource */ |
31836064 | 1036 | loc_cpu_old_entry = oldinfo->entries[raw_smp_processor_id()]; |
72b2b1dd | 1037 | xt_entry_foreach(iter, loc_cpu_old_entry, oldinfo->size) |
0559518b | 1038 | cleanup_entry(iter); |
31836064 | 1039 | |
2e4e6a17 | 1040 | xt_free_table_info(oldinfo); |
d6a2ba07 | 1041 | if (copy_to_user(counters_ptr, counters, |
c5e4ef49 TG |
1042 | sizeof(struct xt_counters) * num_counters) != 0) { |
1043 | /* Silent error, can't fail, new table is already in place */ | |
1044 | net_warn_ratelimited("arptables: counters copy to user failed while replacing table\n"); | |
1045 | } | |
1da177e4 | 1046 | vfree(counters); |
2e4e6a17 | 1047 | xt_table_unlock(t); |
1da177e4 LT |
1048 | return ret; |
1049 | ||
1050 | put_module: | |
1051 | module_put(t->me); | |
2e4e6a17 | 1052 | xt_table_unlock(t); |
1da177e4 | 1053 | free_newinfo_counters_untrans: |
1da177e4 | 1054 | vfree(counters); |
d6a2ba07 PM |
1055 | out: |
1056 | return ret; | |
1057 | } | |
1058 | ||
d5d1baa1 JE |
1059 | static int do_replace(struct net *net, const void __user *user, |
1060 | unsigned int len) | |
d6a2ba07 PM |
1061 | { |
1062 | int ret; | |
1063 | struct arpt_replace tmp; | |
1064 | struct xt_table_info *newinfo; | |
1065 | void *loc_cpu_entry; | |
72b2b1dd | 1066 | struct arpt_entry *iter; |
d6a2ba07 PM |
1067 | |
1068 | if (copy_from_user(&tmp, user, sizeof(tmp)) != 0) | |
1069 | return -EFAULT; | |
1070 | ||
1071 | /* overflow check */ | |
1072 | if (tmp.num_counters >= INT_MAX / sizeof(struct xt_counters)) | |
1073 | return -ENOMEM; | |
42eab94f | 1074 | tmp.name[sizeof(tmp.name)-1] = 0; |
d6a2ba07 PM |
1075 | |
1076 | newinfo = xt_alloc_table_info(tmp.size); | |
1077 | if (!newinfo) | |
1078 | return -ENOMEM; | |
1079 | ||
1080 | /* choose the copy that is on our node/cpu */ | |
1081 | loc_cpu_entry = newinfo->entries[raw_smp_processor_id()]; | |
1082 | if (copy_from_user(loc_cpu_entry, user + sizeof(tmp), | |
1083 | tmp.size) != 0) { | |
1084 | ret = -EFAULT; | |
1085 | goto free_newinfo; | |
1086 | } | |
1087 | ||
0f234214 | 1088 | ret = translate_table(newinfo, loc_cpu_entry, &tmp); |
d6a2ba07 PM |
1089 | if (ret != 0) |
1090 | goto free_newinfo; | |
1091 | ||
1092 | duprintf("arp_tables: Translated table\n"); | |
1093 | ||
79df341a | 1094 | ret = __do_replace(net, tmp.name, tmp.valid_hooks, newinfo, |
d6a2ba07 PM |
1095 | tmp.num_counters, tmp.counters); |
1096 | if (ret) | |
1097 | goto free_newinfo_untrans; | |
1098 | return 0; | |
1099 | ||
1100 | free_newinfo_untrans: | |
72b2b1dd | 1101 | xt_entry_foreach(iter, loc_cpu_entry, newinfo->size) |
0559518b | 1102 | cleanup_entry(iter); |
1da177e4 | 1103 | free_newinfo: |
2e4e6a17 | 1104 | xt_free_table_info(newinfo); |
1da177e4 LT |
1105 | return ret; |
1106 | } | |
1107 | ||
d5d1baa1 JE |
1108 | static int do_add_counters(struct net *net, const void __user *user, |
1109 | unsigned int len, int compat) | |
1da177e4 | 1110 | { |
942e4a2b | 1111 | unsigned int i, curcpu; |
d6a2ba07 PM |
1112 | struct xt_counters_info tmp; |
1113 | struct xt_counters *paddc; | |
1114 | unsigned int num_counters; | |
5452e425 | 1115 | const char *name; |
d6a2ba07 PM |
1116 | int size; |
1117 | void *ptmp; | |
4abff077 | 1118 | struct xt_table *t; |
5452e425 | 1119 | const struct xt_table_info *private; |
6b7d31fc | 1120 | int ret = 0; |
31836064 | 1121 | void *loc_cpu_entry; |
72b2b1dd | 1122 | struct arpt_entry *iter; |
7f5c6d4f | 1123 | unsigned int addend; |
d6a2ba07 PM |
1124 | #ifdef CONFIG_COMPAT |
1125 | struct compat_xt_counters_info compat_tmp; | |
1da177e4 | 1126 | |
d6a2ba07 PM |
1127 | if (compat) { |
1128 | ptmp = &compat_tmp; | |
1129 | size = sizeof(struct compat_xt_counters_info); | |
1130 | } else | |
1131 | #endif | |
1132 | { | |
1133 | ptmp = &tmp; | |
1134 | size = sizeof(struct xt_counters_info); | |
1135 | } | |
1136 | ||
1137 | if (copy_from_user(ptmp, user, size) != 0) | |
1da177e4 LT |
1138 | return -EFAULT; |
1139 | ||
d6a2ba07 PM |
1140 | #ifdef CONFIG_COMPAT |
1141 | if (compat) { | |
1142 | num_counters = compat_tmp.num_counters; | |
1143 | name = compat_tmp.name; | |
1144 | } else | |
1145 | #endif | |
1146 | { | |
1147 | num_counters = tmp.num_counters; | |
1148 | name = tmp.name; | |
1149 | } | |
1150 | ||
1151 | if (len != size + num_counters * sizeof(struct xt_counters)) | |
1da177e4 LT |
1152 | return -EINVAL; |
1153 | ||
e12f8e29 | 1154 | paddc = vmalloc(len - size); |
1da177e4 LT |
1155 | if (!paddc) |
1156 | return -ENOMEM; | |
1157 | ||
d6a2ba07 | 1158 | if (copy_from_user(paddc, user + size, len - size) != 0) { |
1da177e4 LT |
1159 | ret = -EFAULT; |
1160 | goto free; | |
1161 | } | |
1162 | ||
ee999d8b | 1163 | t = xt_find_table_lock(net, NFPROTO_ARP, name); |
0cc8d8df | 1164 | if (IS_ERR_OR_NULL(t)) { |
6b7d31fc | 1165 | ret = t ? PTR_ERR(t) : -ENOENT; |
1da177e4 | 1166 | goto free; |
6b7d31fc | 1167 | } |
1da177e4 | 1168 | |
942e4a2b | 1169 | local_bh_disable(); |
2e4e6a17 | 1170 | private = t->private; |
d6a2ba07 | 1171 | if (private->number != num_counters) { |
1da177e4 LT |
1172 | ret = -EINVAL; |
1173 | goto unlock_up_free; | |
1174 | } | |
1175 | ||
1176 | i = 0; | |
31836064 | 1177 | /* Choose the copy that is on our node */ |
942e4a2b SH |
1178 | curcpu = smp_processor_id(); |
1179 | loc_cpu_entry = private->entries[curcpu]; | |
7f5c6d4f | 1180 | addend = xt_write_recseq_begin(); |
0559518b JE |
1181 | xt_entry_foreach(iter, loc_cpu_entry, private->size) { |
1182 | ADD_COUNTER(iter->counters, paddc[i].bcnt, paddc[i].pcnt); | |
1183 | ++i; | |
1184 | } | |
7f5c6d4f | 1185 | xt_write_recseq_end(addend); |
1da177e4 | 1186 | unlock_up_free: |
942e4a2b | 1187 | local_bh_enable(); |
2e4e6a17 | 1188 | xt_table_unlock(t); |
6b7d31fc | 1189 | module_put(t->me); |
1da177e4 LT |
1190 | free: |
1191 | vfree(paddc); | |
1192 | ||
1193 | return ret; | |
1194 | } | |
1195 | ||
d6a2ba07 | 1196 | #ifdef CONFIG_COMPAT |
0559518b | 1197 | static inline void compat_release_entry(struct compat_arpt_entry *e) |
d6a2ba07 | 1198 | { |
87a2e70d | 1199 | struct xt_entry_target *t; |
d6a2ba07 | 1200 | |
d6a2ba07 PM |
1201 | t = compat_arpt_get_target(e); |
1202 | module_put(t->u.kernel.target->me); | |
d6a2ba07 PM |
1203 | } |
1204 | ||
1205 | static inline int | |
1206 | check_compat_entry_size_and_hooks(struct compat_arpt_entry *e, | |
1207 | struct xt_table_info *newinfo, | |
1208 | unsigned int *size, | |
d5d1baa1 JE |
1209 | const unsigned char *base, |
1210 | const unsigned char *limit, | |
1211 | const unsigned int *hook_entries, | |
1212 | const unsigned int *underflows, | |
d6a2ba07 PM |
1213 | const char *name) |
1214 | { | |
87a2e70d | 1215 | struct xt_entry_target *t; |
d6a2ba07 PM |
1216 | struct xt_target *target; |
1217 | unsigned int entry_offset; | |
1218 | int ret, off, h; | |
1219 | ||
1220 | duprintf("check_compat_entry_size_and_hooks %p\n", e); | |
3666ed1c | 1221 | if ((unsigned long)e % __alignof__(struct compat_arpt_entry) != 0 || |
74afad87 FW |
1222 | (unsigned char *)e + sizeof(struct compat_arpt_entry) >= limit || |
1223 | (unsigned char *)e + e->next_offset > limit) { | |
d6a2ba07 PM |
1224 | duprintf("Bad offset %p, limit = %p\n", e, limit); |
1225 | return -EINVAL; | |
1226 | } | |
1227 | ||
1228 | if (e->next_offset < sizeof(struct compat_arpt_entry) + | |
1229 | sizeof(struct compat_xt_entry_target)) { | |
1230 | duprintf("checking: element %p size %u\n", | |
1231 | e, e->next_offset); | |
1232 | return -EINVAL; | |
1233 | } | |
1234 | ||
1235 | /* For purposes of check_entry casting the compat entry is fine */ | |
0608074c | 1236 | ret = check_entry((struct arpt_entry *)e); |
d6a2ba07 PM |
1237 | if (ret) |
1238 | return ret; | |
1239 | ||
1240 | off = sizeof(struct arpt_entry) - sizeof(struct compat_arpt_entry); | |
1241 | entry_offset = (void *)e - (void *)base; | |
1242 | ||
1243 | t = compat_arpt_get_target(e); | |
d2a7b6ba JE |
1244 | target = xt_request_find_target(NFPROTO_ARP, t->u.user.name, |
1245 | t->u.user.revision); | |
1246 | if (IS_ERR(target)) { | |
d6a2ba07 PM |
1247 | duprintf("check_compat_entry_size_and_hooks: `%s' not found\n", |
1248 | t->u.user.name); | |
d2a7b6ba | 1249 | ret = PTR_ERR(target); |
d6a2ba07 PM |
1250 | goto out; |
1251 | } | |
1252 | t->u.kernel.target = target; | |
1253 | ||
1254 | off += xt_compat_target_offset(target); | |
1255 | *size += off; | |
ee999d8b | 1256 | ret = xt_compat_add_offset(NFPROTO_ARP, entry_offset, off); |
d6a2ba07 PM |
1257 | if (ret) |
1258 | goto release_target; | |
1259 | ||
1260 | /* Check hooks & underflows */ | |
1261 | for (h = 0; h < NF_ARP_NUMHOOKS; h++) { | |
1262 | if ((unsigned char *)e - base == hook_entries[h]) | |
1263 | newinfo->hook_entry[h] = hook_entries[h]; | |
1264 | if ((unsigned char *)e - base == underflows[h]) | |
1265 | newinfo->underflow[h] = underflows[h]; | |
1266 | } | |
1267 | ||
1268 | /* Clear counters and comefrom */ | |
1269 | memset(&e->counters, 0, sizeof(e->counters)); | |
1270 | e->comefrom = 0; | |
d6a2ba07 PM |
1271 | return 0; |
1272 | ||
1273 | release_target: | |
1274 | module_put(t->u.kernel.target->me); | |
1275 | out: | |
1276 | return ret; | |
1277 | } | |
1278 | ||
1279 | static int | |
1280 | compat_copy_entry_from_user(struct compat_arpt_entry *e, void **dstptr, | |
1281 | unsigned int *size, const char *name, | |
1282 | struct xt_table_info *newinfo, unsigned char *base) | |
1283 | { | |
87a2e70d | 1284 | struct xt_entry_target *t; |
d6a2ba07 PM |
1285 | struct xt_target *target; |
1286 | struct arpt_entry *de; | |
1287 | unsigned int origsize; | |
1288 | int ret, h; | |
1289 | ||
1290 | ret = 0; | |
1291 | origsize = *size; | |
1292 | de = (struct arpt_entry *)*dstptr; | |
1293 | memcpy(de, e, sizeof(struct arpt_entry)); | |
1294 | memcpy(&de->counters, &e->counters, sizeof(e->counters)); | |
1295 | ||
1296 | *dstptr += sizeof(struct arpt_entry); | |
1297 | *size += sizeof(struct arpt_entry) - sizeof(struct compat_arpt_entry); | |
1298 | ||
1299 | de->target_offset = e->target_offset - (origsize - *size); | |
1300 | t = compat_arpt_get_target(e); | |
1301 | target = t->u.kernel.target; | |
1302 | xt_compat_target_from_user(t, dstptr, size); | |
1303 | ||
1304 | de->next_offset = e->next_offset - (origsize - *size); | |
1305 | for (h = 0; h < NF_ARP_NUMHOOKS; h++) { | |
1306 | if ((unsigned char *)de - base < newinfo->hook_entry[h]) | |
1307 | newinfo->hook_entry[h] -= origsize - *size; | |
1308 | if ((unsigned char *)de - base < newinfo->underflow[h]) | |
1309 | newinfo->underflow[h] -= origsize - *size; | |
1310 | } | |
1311 | return ret; | |
1312 | } | |
1313 | ||
d6a2ba07 PM |
1314 | static int translate_compat_table(const char *name, |
1315 | unsigned int valid_hooks, | |
1316 | struct xt_table_info **pinfo, | |
1317 | void **pentry0, | |
1318 | unsigned int total_size, | |
1319 | unsigned int number, | |
1320 | unsigned int *hook_entries, | |
1321 | unsigned int *underflows) | |
1322 | { | |
1323 | unsigned int i, j; | |
1324 | struct xt_table_info *newinfo, *info; | |
1325 | void *pos, *entry0, *entry1; | |
72b2b1dd JE |
1326 | struct compat_arpt_entry *iter0; |
1327 | struct arpt_entry *iter1; | |
d6a2ba07 | 1328 | unsigned int size; |
72b2b1dd | 1329 | int ret = 0; |
d6a2ba07 PM |
1330 | |
1331 | info = *pinfo; | |
1332 | entry0 = *pentry0; | |
1333 | size = total_size; | |
1334 | info->number = number; | |
1335 | ||
1336 | /* Init all hooks to impossible value. */ | |
1337 | for (i = 0; i < NF_ARP_NUMHOOKS; i++) { | |
1338 | info->hook_entry[i] = 0xFFFFFFFF; | |
1339 | info->underflow[i] = 0xFFFFFFFF; | |
1340 | } | |
1341 | ||
1342 | duprintf("translate_compat_table: size %u\n", info->size); | |
1343 | j = 0; | |
ee999d8b | 1344 | xt_compat_lock(NFPROTO_ARP); |
255d0dc3 | 1345 | xt_compat_init_offsets(NFPROTO_ARP, number); |
d6a2ba07 | 1346 | /* Walk through entries, checking offsets. */ |
72b2b1dd JE |
1347 | xt_entry_foreach(iter0, entry0, total_size) { |
1348 | ret = check_compat_entry_size_and_hooks(iter0, info, &size, | |
6b4ff2d7 JE |
1349 | entry0, |
1350 | entry0 + total_size, | |
1351 | hook_entries, | |
1352 | underflows, | |
1353 | name); | |
72b2b1dd | 1354 | if (ret != 0) |
0559518b JE |
1355 | goto out_unlock; |
1356 | ++j; | |
72b2b1dd | 1357 | } |
d6a2ba07 PM |
1358 | |
1359 | ret = -EINVAL; | |
1360 | if (j != number) { | |
1361 | duprintf("translate_compat_table: %u not %u entries\n", | |
1362 | j, number); | |
1363 | goto out_unlock; | |
1364 | } | |
1365 | ||
1366 | /* Check hooks all assigned */ | |
1367 | for (i = 0; i < NF_ARP_NUMHOOKS; i++) { | |
1368 | /* Only hooks which are valid */ | |
1369 | if (!(valid_hooks & (1 << i))) | |
1370 | continue; | |
1371 | if (info->hook_entry[i] == 0xFFFFFFFF) { | |
1372 | duprintf("Invalid hook entry %u %u\n", | |
1373 | i, hook_entries[i]); | |
1374 | goto out_unlock; | |
1375 | } | |
1376 | if (info->underflow[i] == 0xFFFFFFFF) { | |
1377 | duprintf("Invalid underflow %u %u\n", | |
1378 | i, underflows[i]); | |
1379 | goto out_unlock; | |
1380 | } | |
1381 | } | |
1382 | ||
1383 | ret = -ENOMEM; | |
1384 | newinfo = xt_alloc_table_info(size); | |
1385 | if (!newinfo) | |
1386 | goto out_unlock; | |
1387 | ||
1388 | newinfo->number = number; | |
1389 | for (i = 0; i < NF_ARP_NUMHOOKS; i++) { | |
1390 | newinfo->hook_entry[i] = info->hook_entry[i]; | |
1391 | newinfo->underflow[i] = info->underflow[i]; | |
1392 | } | |
1393 | entry1 = newinfo->entries[raw_smp_processor_id()]; | |
1394 | pos = entry1; | |
1395 | size = total_size; | |
72b2b1dd | 1396 | xt_entry_foreach(iter0, entry0, total_size) { |
6b4ff2d7 JE |
1397 | ret = compat_copy_entry_from_user(iter0, &pos, &size, |
1398 | name, newinfo, entry1); | |
72b2b1dd JE |
1399 | if (ret != 0) |
1400 | break; | |
1401 | } | |
ee999d8b JE |
1402 | xt_compat_flush_offsets(NFPROTO_ARP); |
1403 | xt_compat_unlock(NFPROTO_ARP); | |
d6a2ba07 PM |
1404 | if (ret) |
1405 | goto free_newinfo; | |
1406 | ||
1407 | ret = -ELOOP; | |
1408 | if (!mark_source_chains(newinfo, valid_hooks, entry1)) | |
1409 | goto free_newinfo; | |
1410 | ||
1411 | i = 0; | |
72b2b1dd | 1412 | xt_entry_foreach(iter1, entry1, newinfo->size) { |
0559518b | 1413 | ret = check_target(iter1, name); |
72b2b1dd JE |
1414 | if (ret != 0) |
1415 | break; | |
0559518b | 1416 | ++i; |
cca77b7c FW |
1417 | if (strcmp(arpt_get_target(iter1)->u.user.name, |
1418 | XT_ERROR_TARGET) == 0) | |
1419 | ++newinfo->stacksize; | |
72b2b1dd | 1420 | } |
d6a2ba07 | 1421 | if (ret) { |
72b2b1dd JE |
1422 | /* |
1423 | * The first i matches need cleanup_entry (calls ->destroy) | |
1424 | * because they had called ->check already. The other j-i | |
1425 | * entries need only release. | |
1426 | */ | |
1427 | int skip = i; | |
d6a2ba07 | 1428 | j -= i; |
72b2b1dd JE |
1429 | xt_entry_foreach(iter0, entry0, newinfo->size) { |
1430 | if (skip-- > 0) | |
1431 | continue; | |
0559518b | 1432 | if (j-- == 0) |
72b2b1dd | 1433 | break; |
0559518b | 1434 | compat_release_entry(iter0); |
72b2b1dd | 1435 | } |
0559518b JE |
1436 | xt_entry_foreach(iter1, entry1, newinfo->size) { |
1437 | if (i-- == 0) | |
72b2b1dd | 1438 | break; |
0559518b JE |
1439 | cleanup_entry(iter1); |
1440 | } | |
d6a2ba07 PM |
1441 | xt_free_table_info(newinfo); |
1442 | return ret; | |
1443 | } | |
1444 | ||
1445 | /* And one copy for every other CPU */ | |
1446 | for_each_possible_cpu(i) | |
1447 | if (newinfo->entries[i] && newinfo->entries[i] != entry1) | |
1448 | memcpy(newinfo->entries[i], entry1, newinfo->size); | |
1449 | ||
1450 | *pinfo = newinfo; | |
1451 | *pentry0 = entry1; | |
1452 | xt_free_table_info(info); | |
1453 | return 0; | |
1454 | ||
1455 | free_newinfo: | |
1456 | xt_free_table_info(newinfo); | |
1457 | out: | |
0559518b JE |
1458 | xt_entry_foreach(iter0, entry0, total_size) { |
1459 | if (j-- == 0) | |
72b2b1dd | 1460 | break; |
0559518b JE |
1461 | compat_release_entry(iter0); |
1462 | } | |
d6a2ba07 PM |
1463 | return ret; |
1464 | out_unlock: | |
ee999d8b JE |
1465 | xt_compat_flush_offsets(NFPROTO_ARP); |
1466 | xt_compat_unlock(NFPROTO_ARP); | |
d6a2ba07 PM |
1467 | goto out; |
1468 | } | |
1469 | ||
1470 | struct compat_arpt_replace { | |
12b00c2c | 1471 | char name[XT_TABLE_MAXNAMELEN]; |
d6a2ba07 PM |
1472 | u32 valid_hooks; |
1473 | u32 num_entries; | |
1474 | u32 size; | |
1475 | u32 hook_entry[NF_ARP_NUMHOOKS]; | |
1476 | u32 underflow[NF_ARP_NUMHOOKS]; | |
1477 | u32 num_counters; | |
1478 | compat_uptr_t counters; | |
1479 | struct compat_arpt_entry entries[0]; | |
1480 | }; | |
1481 | ||
79df341a AD |
1482 | static int compat_do_replace(struct net *net, void __user *user, |
1483 | unsigned int len) | |
d6a2ba07 PM |
1484 | { |
1485 | int ret; | |
1486 | struct compat_arpt_replace tmp; | |
1487 | struct xt_table_info *newinfo; | |
1488 | void *loc_cpu_entry; | |
72b2b1dd | 1489 | struct arpt_entry *iter; |
d6a2ba07 PM |
1490 | |
1491 | if (copy_from_user(&tmp, user, sizeof(tmp)) != 0) | |
1492 | return -EFAULT; | |
1493 | ||
1494 | /* overflow check */ | |
1495 | if (tmp.size >= INT_MAX / num_possible_cpus()) | |
1496 | return -ENOMEM; | |
1497 | if (tmp.num_counters >= INT_MAX / sizeof(struct xt_counters)) | |
1498 | return -ENOMEM; | |
42eab94f | 1499 | tmp.name[sizeof(tmp.name)-1] = 0; |
d6a2ba07 PM |
1500 | |
1501 | newinfo = xt_alloc_table_info(tmp.size); | |
1502 | if (!newinfo) | |
1503 | return -ENOMEM; | |
1504 | ||
1505 | /* choose the copy that is on our node/cpu */ | |
1506 | loc_cpu_entry = newinfo->entries[raw_smp_processor_id()]; | |
1507 | if (copy_from_user(loc_cpu_entry, user + sizeof(tmp), tmp.size) != 0) { | |
1508 | ret = -EFAULT; | |
1509 | goto free_newinfo; | |
1510 | } | |
1511 | ||
1512 | ret = translate_compat_table(tmp.name, tmp.valid_hooks, | |
1513 | &newinfo, &loc_cpu_entry, tmp.size, | |
1514 | tmp.num_entries, tmp.hook_entry, | |
1515 | tmp.underflow); | |
1516 | if (ret != 0) | |
1517 | goto free_newinfo; | |
1518 | ||
1519 | duprintf("compat_do_replace: Translated table\n"); | |
1520 | ||
79df341a | 1521 | ret = __do_replace(net, tmp.name, tmp.valid_hooks, newinfo, |
d6a2ba07 PM |
1522 | tmp.num_counters, compat_ptr(tmp.counters)); |
1523 | if (ret) | |
1524 | goto free_newinfo_untrans; | |
1525 | return 0; | |
1526 | ||
1527 | free_newinfo_untrans: | |
72b2b1dd | 1528 | xt_entry_foreach(iter, loc_cpu_entry, newinfo->size) |
0559518b | 1529 | cleanup_entry(iter); |
d6a2ba07 PM |
1530 | free_newinfo: |
1531 | xt_free_table_info(newinfo); | |
1532 | return ret; | |
1533 | } | |
1534 | ||
1535 | static int compat_do_arpt_set_ctl(struct sock *sk, int cmd, void __user *user, | |
1536 | unsigned int len) | |
1537 | { | |
1538 | int ret; | |
1539 | ||
52e804c6 | 1540 | if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) |
d6a2ba07 PM |
1541 | return -EPERM; |
1542 | ||
1543 | switch (cmd) { | |
1544 | case ARPT_SO_SET_REPLACE: | |
3b1e0a65 | 1545 | ret = compat_do_replace(sock_net(sk), user, len); |
d6a2ba07 PM |
1546 | break; |
1547 | ||
1548 | case ARPT_SO_SET_ADD_COUNTERS: | |
3b1e0a65 | 1549 | ret = do_add_counters(sock_net(sk), user, len, 1); |
d6a2ba07 PM |
1550 | break; |
1551 | ||
1552 | default: | |
1553 | duprintf("do_arpt_set_ctl: unknown request %i\n", cmd); | |
1554 | ret = -EINVAL; | |
1555 | } | |
1556 | ||
1557 | return ret; | |
1558 | } | |
1559 | ||
1560 | static int compat_copy_entry_to_user(struct arpt_entry *e, void __user **dstptr, | |
1561 | compat_uint_t *size, | |
1562 | struct xt_counters *counters, | |
0559518b | 1563 | unsigned int i) |
d6a2ba07 | 1564 | { |
87a2e70d | 1565 | struct xt_entry_target *t; |
d6a2ba07 PM |
1566 | struct compat_arpt_entry __user *ce; |
1567 | u_int16_t target_offset, next_offset; | |
1568 | compat_uint_t origsize; | |
1569 | int ret; | |
1570 | ||
d6a2ba07 PM |
1571 | origsize = *size; |
1572 | ce = (struct compat_arpt_entry __user *)*dstptr; | |
0559518b JE |
1573 | if (copy_to_user(ce, e, sizeof(struct arpt_entry)) != 0 || |
1574 | copy_to_user(&ce->counters, &counters[i], | |
1575 | sizeof(counters[i])) != 0) | |
1576 | return -EFAULT; | |
d6a2ba07 PM |
1577 | |
1578 | *dstptr += sizeof(struct compat_arpt_entry); | |
1579 | *size -= sizeof(struct arpt_entry) - sizeof(struct compat_arpt_entry); | |
1580 | ||
1581 | target_offset = e->target_offset - (origsize - *size); | |
1582 | ||
1583 | t = arpt_get_target(e); | |
1584 | ret = xt_compat_target_to_user(t, dstptr, size); | |
1585 | if (ret) | |
0559518b | 1586 | return ret; |
d6a2ba07 | 1587 | next_offset = e->next_offset - (origsize - *size); |
0559518b JE |
1588 | if (put_user(target_offset, &ce->target_offset) != 0 || |
1589 | put_user(next_offset, &ce->next_offset) != 0) | |
1590 | return -EFAULT; | |
d6a2ba07 | 1591 | return 0; |
d6a2ba07 PM |
1592 | } |
1593 | ||
1594 | static int compat_copy_entries_to_user(unsigned int total_size, | |
4abff077 | 1595 | struct xt_table *table, |
d6a2ba07 PM |
1596 | void __user *userptr) |
1597 | { | |
1598 | struct xt_counters *counters; | |
5452e425 | 1599 | const struct xt_table_info *private = table->private; |
d6a2ba07 PM |
1600 | void __user *pos; |
1601 | unsigned int size; | |
1602 | int ret = 0; | |
1603 | void *loc_cpu_entry; | |
1604 | unsigned int i = 0; | |
72b2b1dd | 1605 | struct arpt_entry *iter; |
d6a2ba07 PM |
1606 | |
1607 | counters = alloc_counters(table); | |
1608 | if (IS_ERR(counters)) | |
1609 | return PTR_ERR(counters); | |
1610 | ||
1611 | /* choose the copy on our node/cpu */ | |
1612 | loc_cpu_entry = private->entries[raw_smp_processor_id()]; | |
1613 | pos = userptr; | |
1614 | size = total_size; | |
72b2b1dd JE |
1615 | xt_entry_foreach(iter, loc_cpu_entry, total_size) { |
1616 | ret = compat_copy_entry_to_user(iter, &pos, | |
6b4ff2d7 | 1617 | &size, counters, i++); |
72b2b1dd JE |
1618 | if (ret != 0) |
1619 | break; | |
1620 | } | |
d6a2ba07 PM |
1621 | vfree(counters); |
1622 | return ret; | |
1623 | } | |
1624 | ||
1625 | struct compat_arpt_get_entries { | |
12b00c2c | 1626 | char name[XT_TABLE_MAXNAMELEN]; |
d6a2ba07 PM |
1627 | compat_uint_t size; |
1628 | struct compat_arpt_entry entrytable[0]; | |
1629 | }; | |
1630 | ||
79df341a AD |
1631 | static int compat_get_entries(struct net *net, |
1632 | struct compat_arpt_get_entries __user *uptr, | |
d6a2ba07 PM |
1633 | int *len) |
1634 | { | |
1635 | int ret; | |
1636 | struct compat_arpt_get_entries get; | |
4abff077 | 1637 | struct xt_table *t; |
d6a2ba07 PM |
1638 | |
1639 | if (*len < sizeof(get)) { | |
1640 | duprintf("compat_get_entries: %u < %zu\n", *len, sizeof(get)); | |
1641 | return -EINVAL; | |
1642 | } | |
1643 | if (copy_from_user(&get, uptr, sizeof(get)) != 0) | |
1644 | return -EFAULT; | |
1645 | if (*len != sizeof(struct compat_arpt_get_entries) + get.size) { | |
1646 | duprintf("compat_get_entries: %u != %zu\n", | |
1647 | *len, sizeof(get) + get.size); | |
1648 | return -EINVAL; | |
1649 | } | |
1650 | ||
ee999d8b JE |
1651 | xt_compat_lock(NFPROTO_ARP); |
1652 | t = xt_find_table_lock(net, NFPROTO_ARP, get.name); | |
0cc8d8df | 1653 | if (!IS_ERR_OR_NULL(t)) { |
5452e425 | 1654 | const struct xt_table_info *private = t->private; |
d6a2ba07 PM |
1655 | struct xt_table_info info; |
1656 | ||
1657 | duprintf("t->private->number = %u\n", private->number); | |
1658 | ret = compat_table_info(private, &info); | |
1659 | if (!ret && get.size == info.size) { | |
1660 | ret = compat_copy_entries_to_user(private->size, | |
1661 | t, uptr->entrytable); | |
1662 | } else if (!ret) { | |
1663 | duprintf("compat_get_entries: I've got %u not %u!\n", | |
1664 | private->size, get.size); | |
544473c1 | 1665 | ret = -EAGAIN; |
d6a2ba07 | 1666 | } |
ee999d8b | 1667 | xt_compat_flush_offsets(NFPROTO_ARP); |
d6a2ba07 PM |
1668 | module_put(t->me); |
1669 | xt_table_unlock(t); | |
1670 | } else | |
1671 | ret = t ? PTR_ERR(t) : -ENOENT; | |
1672 | ||
ee999d8b | 1673 | xt_compat_unlock(NFPROTO_ARP); |
d6a2ba07 PM |
1674 | return ret; |
1675 | } | |
1676 | ||
1677 | static int do_arpt_get_ctl(struct sock *, int, void __user *, int *); | |
1678 | ||
1679 | static int compat_do_arpt_get_ctl(struct sock *sk, int cmd, void __user *user, | |
1680 | int *len) | |
1681 | { | |
1682 | int ret; | |
1683 | ||
52e804c6 | 1684 | if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) |
d6a2ba07 PM |
1685 | return -EPERM; |
1686 | ||
1687 | switch (cmd) { | |
1688 | case ARPT_SO_GET_INFO: | |
3b1e0a65 | 1689 | ret = get_info(sock_net(sk), user, len, 1); |
d6a2ba07 PM |
1690 | break; |
1691 | case ARPT_SO_GET_ENTRIES: | |
3b1e0a65 | 1692 | ret = compat_get_entries(sock_net(sk), user, len); |
d6a2ba07 PM |
1693 | break; |
1694 | default: | |
1695 | ret = do_arpt_get_ctl(sk, cmd, user, len); | |
1696 | } | |
1697 | return ret; | |
1698 | } | |
1699 | #endif | |
1700 | ||
1da177e4 LT |
1701 | static int do_arpt_set_ctl(struct sock *sk, int cmd, void __user *user, unsigned int len) |
1702 | { | |
1703 | int ret; | |
1704 | ||
52e804c6 | 1705 | if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) |
1da177e4 LT |
1706 | return -EPERM; |
1707 | ||
1708 | switch (cmd) { | |
1709 | case ARPT_SO_SET_REPLACE: | |
3b1e0a65 | 1710 | ret = do_replace(sock_net(sk), user, len); |
1da177e4 LT |
1711 | break; |
1712 | ||
1713 | case ARPT_SO_SET_ADD_COUNTERS: | |
3b1e0a65 | 1714 | ret = do_add_counters(sock_net(sk), user, len, 0); |
1da177e4 LT |
1715 | break; |
1716 | ||
1717 | default: | |
1718 | duprintf("do_arpt_set_ctl: unknown request %i\n", cmd); | |
1719 | ret = -EINVAL; | |
1720 | } | |
1721 | ||
1722 | return ret; | |
1723 | } | |
1724 | ||
1725 | static int do_arpt_get_ctl(struct sock *sk, int cmd, void __user *user, int *len) | |
1726 | { | |
1727 | int ret; | |
1728 | ||
52e804c6 | 1729 | if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) |
1da177e4 LT |
1730 | return -EPERM; |
1731 | ||
1732 | switch (cmd) { | |
41acd975 | 1733 | case ARPT_SO_GET_INFO: |
3b1e0a65 | 1734 | ret = get_info(sock_net(sk), user, len, 0); |
41acd975 | 1735 | break; |
1da177e4 | 1736 | |
11f6dff8 | 1737 | case ARPT_SO_GET_ENTRIES: |
3b1e0a65 | 1738 | ret = get_entries(sock_net(sk), user, len); |
1da177e4 | 1739 | break; |
1da177e4 | 1740 | |
6b7d31fc | 1741 | case ARPT_SO_GET_REVISION_TARGET: { |
2e4e6a17 | 1742 | struct xt_get_revision rev; |
6b7d31fc HW |
1743 | |
1744 | if (*len != sizeof(rev)) { | |
1745 | ret = -EINVAL; | |
1746 | break; | |
1747 | } | |
1748 | if (copy_from_user(&rev, user, sizeof(rev)) != 0) { | |
1749 | ret = -EFAULT; | |
1750 | break; | |
1751 | } | |
42eab94f | 1752 | rev.name[sizeof(rev.name)-1] = 0; |
6b7d31fc | 1753 | |
ee999d8b | 1754 | try_then_request_module(xt_find_revision(NFPROTO_ARP, rev.name, |
2e4e6a17 | 1755 | rev.revision, 1, &ret), |
6b7d31fc HW |
1756 | "arpt_%s", rev.name); |
1757 | break; | |
1758 | } | |
1759 | ||
1da177e4 LT |
1760 | default: |
1761 | duprintf("do_arpt_get_ctl: unknown request %i\n", cmd); | |
1762 | ret = -EINVAL; | |
1763 | } | |
1764 | ||
1765 | return ret; | |
1766 | } | |
1767 | ||
35aad0ff JE |
1768 | struct xt_table *arpt_register_table(struct net *net, |
1769 | const struct xt_table *table, | |
4abff077 | 1770 | const struct arpt_replace *repl) |
1da177e4 LT |
1771 | { |
1772 | int ret; | |
2e4e6a17 | 1773 | struct xt_table_info *newinfo; |
f3c5c1bf | 1774 | struct xt_table_info bootstrap = {0}; |
31836064 | 1775 | void *loc_cpu_entry; |
a98da11d | 1776 | struct xt_table *new_table; |
1da177e4 | 1777 | |
2e4e6a17 | 1778 | newinfo = xt_alloc_table_info(repl->size); |
1da177e4 LT |
1779 | if (!newinfo) { |
1780 | ret = -ENOMEM; | |
44d34e72 | 1781 | goto out; |
1da177e4 | 1782 | } |
31836064 ED |
1783 | |
1784 | /* choose the copy on our node/cpu */ | |
1785 | loc_cpu_entry = newinfo->entries[raw_smp_processor_id()]; | |
1786 | memcpy(loc_cpu_entry, repl->entries, repl->size); | |
1da177e4 | 1787 | |
0f234214 | 1788 | ret = translate_table(newinfo, loc_cpu_entry, repl); |
1da177e4 | 1789 | duprintf("arpt_register_table: translate table gives %d\n", ret); |
44d34e72 AD |
1790 | if (ret != 0) |
1791 | goto out_free; | |
1da177e4 | 1792 | |
79df341a | 1793 | new_table = xt_register_table(net, table, &bootstrap, newinfo); |
a98da11d | 1794 | if (IS_ERR(new_table)) { |
44d34e72 AD |
1795 | ret = PTR_ERR(new_table); |
1796 | goto out_free; | |
1da177e4 | 1797 | } |
44d34e72 | 1798 | return new_table; |
1da177e4 | 1799 | |
44d34e72 AD |
1800 | out_free: |
1801 | xt_free_table_info(newinfo); | |
1802 | out: | |
1803 | return ERR_PTR(ret); | |
1da177e4 LT |
1804 | } |
1805 | ||
4abff077 | 1806 | void arpt_unregister_table(struct xt_table *table) |
1da177e4 | 1807 | { |
2e4e6a17 | 1808 | struct xt_table_info *private; |
31836064 | 1809 | void *loc_cpu_entry; |
df200969 | 1810 | struct module *table_owner = table->me; |
72b2b1dd | 1811 | struct arpt_entry *iter; |
31836064 | 1812 | |
2e4e6a17 | 1813 | private = xt_unregister_table(table); |
1da177e4 LT |
1814 | |
1815 | /* Decrease module usage counts and free resources */ | |
2e4e6a17 | 1816 | loc_cpu_entry = private->entries[raw_smp_processor_id()]; |
72b2b1dd | 1817 | xt_entry_foreach(iter, loc_cpu_entry, private->size) |
0559518b | 1818 | cleanup_entry(iter); |
df200969 AD |
1819 | if (private->number > private->initial_entries) |
1820 | module_put(table_owner); | |
2e4e6a17 | 1821 | xt_free_table_info(private); |
1da177e4 LT |
1822 | } |
1823 | ||
1824 | /* The built-in targets: standard (NULL) and error. */ | |
4538506b JE |
1825 | static struct xt_target arpt_builtin_tg[] __read_mostly = { |
1826 | { | |
243bf6e2 | 1827 | .name = XT_STANDARD_TARGET, |
4538506b JE |
1828 | .targetsize = sizeof(int), |
1829 | .family = NFPROTO_ARP, | |
d6a2ba07 | 1830 | #ifdef CONFIG_COMPAT |
4538506b JE |
1831 | .compatsize = sizeof(compat_int_t), |
1832 | .compat_from_user = compat_standard_from_user, | |
1833 | .compat_to_user = compat_standard_to_user, | |
d6a2ba07 | 1834 | #endif |
4538506b JE |
1835 | }, |
1836 | { | |
243bf6e2 | 1837 | .name = XT_ERROR_TARGET, |
4538506b | 1838 | .target = arpt_error, |
12b00c2c | 1839 | .targetsize = XT_FUNCTION_MAXNAMELEN, |
4538506b JE |
1840 | .family = NFPROTO_ARP, |
1841 | }, | |
1da177e4 LT |
1842 | }; |
1843 | ||
1844 | static struct nf_sockopt_ops arpt_sockopts = { | |
1845 | .pf = PF_INET, | |
1846 | .set_optmin = ARPT_BASE_CTL, | |
1847 | .set_optmax = ARPT_SO_SET_MAX+1, | |
1848 | .set = do_arpt_set_ctl, | |
d6a2ba07 PM |
1849 | #ifdef CONFIG_COMPAT |
1850 | .compat_set = compat_do_arpt_set_ctl, | |
1851 | #endif | |
1da177e4 LT |
1852 | .get_optmin = ARPT_BASE_CTL, |
1853 | .get_optmax = ARPT_SO_GET_MAX+1, | |
1854 | .get = do_arpt_get_ctl, | |
d6a2ba07 PM |
1855 | #ifdef CONFIG_COMPAT |
1856 | .compat_get = compat_do_arpt_get_ctl, | |
1857 | #endif | |
16fcec35 | 1858 | .owner = THIS_MODULE, |
1da177e4 LT |
1859 | }; |
1860 | ||
3cb609d5 AD |
1861 | static int __net_init arp_tables_net_init(struct net *net) |
1862 | { | |
ee999d8b | 1863 | return xt_proto_init(net, NFPROTO_ARP); |
3cb609d5 AD |
1864 | } |
1865 | ||
1866 | static void __net_exit arp_tables_net_exit(struct net *net) | |
1867 | { | |
ee999d8b | 1868 | xt_proto_fini(net, NFPROTO_ARP); |
3cb609d5 AD |
1869 | } |
1870 | ||
1871 | static struct pernet_operations arp_tables_net_ops = { | |
1872 | .init = arp_tables_net_init, | |
1873 | .exit = arp_tables_net_exit, | |
1874 | }; | |
1875 | ||
65b4b4e8 | 1876 | static int __init arp_tables_init(void) |
1da177e4 LT |
1877 | { |
1878 | int ret; | |
1879 | ||
3cb609d5 | 1880 | ret = register_pernet_subsys(&arp_tables_net_ops); |
0eff66e6 PM |
1881 | if (ret < 0) |
1882 | goto err1; | |
2e4e6a17 | 1883 | |
25985edc | 1884 | /* No one else will be downing sem now, so we won't sleep */ |
4538506b | 1885 | ret = xt_register_targets(arpt_builtin_tg, ARRAY_SIZE(arpt_builtin_tg)); |
0eff66e6 PM |
1886 | if (ret < 0) |
1887 | goto err2; | |
1da177e4 LT |
1888 | |
1889 | /* Register setsockopt */ | |
1890 | ret = nf_register_sockopt(&arpt_sockopts); | |
0eff66e6 PM |
1891 | if (ret < 0) |
1892 | goto err4; | |
1da177e4 | 1893 | |
a887c1c1 | 1894 | printk(KERN_INFO "arp_tables: (C) 2002 David S. Miller\n"); |
1da177e4 | 1895 | return 0; |
0eff66e6 PM |
1896 | |
1897 | err4: | |
4538506b | 1898 | xt_unregister_targets(arpt_builtin_tg, ARRAY_SIZE(arpt_builtin_tg)); |
0eff66e6 | 1899 | err2: |
3cb609d5 | 1900 | unregister_pernet_subsys(&arp_tables_net_ops); |
0eff66e6 PM |
1901 | err1: |
1902 | return ret; | |
1da177e4 LT |
1903 | } |
1904 | ||
65b4b4e8 | 1905 | static void __exit arp_tables_fini(void) |
1da177e4 LT |
1906 | { |
1907 | nf_unregister_sockopt(&arpt_sockopts); | |
4538506b | 1908 | xt_unregister_targets(arpt_builtin_tg, ARRAY_SIZE(arpt_builtin_tg)); |
3cb609d5 | 1909 | unregister_pernet_subsys(&arp_tables_net_ops); |
1da177e4 LT |
1910 | } |
1911 | ||
1912 | EXPORT_SYMBOL(arpt_register_table); | |
1913 | EXPORT_SYMBOL(arpt_unregister_table); | |
1914 | EXPORT_SYMBOL(arpt_do_table); | |
1da177e4 | 1915 | |
65b4b4e8 AM |
1916 | module_init(arp_tables_init); |
1917 | module_exit(arp_tables_fini); |