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. */ |
1ee858dd | 353 | static inline bool unconditional(const struct arpt_entry *e) |
1da177e4 | 354 | { |
47901dc2 | 355 | static const struct arpt_arp uncond; |
1da177e4 | 356 | |
1ee858dd FW |
357 | return e->target_offset == sizeof(struct arpt_entry) && |
358 | memcmp(&e->arp, &uncond, sizeof(uncond)) == 0; | |
1da177e4 LT |
359 | } |
360 | ||
361 | /* Figures out from what hook each rule can be called: returns 0 if | |
362 | * there are loops. Puts hook bitmask in comefrom. | |
363 | */ | |
d5d1baa1 | 364 | static int mark_source_chains(const struct xt_table_info *newinfo, |
31836064 | 365 | unsigned int valid_hooks, void *entry0) |
1da177e4 LT |
366 | { |
367 | unsigned int hook; | |
368 | ||
369 | /* No recursion; use packet counter to save back ptrs (reset | |
370 | * to 0 as we leave), and comefrom to save source hook bitmask. | |
371 | */ | |
372 | for (hook = 0; hook < NF_ARP_NUMHOOKS; hook++) { | |
373 | unsigned int pos = newinfo->hook_entry[hook]; | |
374 | struct arpt_entry *e | |
31836064 | 375 | = (struct arpt_entry *)(entry0 + pos); |
1da177e4 LT |
376 | |
377 | if (!(valid_hooks & (1 << hook))) | |
378 | continue; | |
379 | ||
380 | /* Set initial back pointer. */ | |
381 | e->counters.pcnt = pos; | |
382 | ||
383 | for (;;) { | |
87a2e70d | 384 | const struct xt_standard_target *t |
d5d1baa1 | 385 | = (void *)arpt_get_target_c(e); |
e1b4b9f3 | 386 | int visited = e->comefrom & (1 << hook); |
1da177e4 LT |
387 | |
388 | if (e->comefrom & (1 << NF_ARP_NUMHOOKS)) { | |
654d0fbd | 389 | pr_notice("arptables: loop hook %u pos %u %08X.\n", |
1da177e4 LT |
390 | hook, pos, e->comefrom); |
391 | return 0; | |
392 | } | |
393 | e->comefrom | |
394 | |= ((1 << hook) | (1 << NF_ARP_NUMHOOKS)); | |
395 | ||
396 | /* Unconditional return/END. */ | |
1ee858dd | 397 | if ((unconditional(e) && |
3666ed1c | 398 | (strcmp(t->target.u.user.name, |
243bf6e2 | 399 | XT_STANDARD_TARGET) == 0) && |
1ee858dd | 400 | t->verdict < 0) || 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); |
82e2616a FW |
433 | if (pos + size >= newinfo->size) |
434 | return 0; | |
1da177e4 LT |
435 | e->counters.pcnt = pos; |
436 | pos += size; | |
437 | } else { | |
438 | int newpos = t->verdict; | |
439 | ||
440 | if (strcmp(t->target.u.user.name, | |
243bf6e2 | 441 | XT_STANDARD_TARGET) == 0 && |
3666ed1c | 442 | newpos >= 0) { |
74c9c0c1 DM |
443 | if (newpos > newinfo->size - |
444 | sizeof(struct arpt_entry)) { | |
445 | duprintf("mark_source_chains: " | |
446 | "bad verdict (%i)\n", | |
447 | newpos); | |
448 | return 0; | |
449 | } | |
450 | ||
1da177e4 LT |
451 | /* This a jump; chase it. */ |
452 | duprintf("Jump rule %u -> %u\n", | |
453 | pos, newpos); | |
454 | } else { | |
455 | /* ... this is a fallthru */ | |
456 | newpos = pos + e->next_offset; | |
82e2616a FW |
457 | if (newpos >= newinfo->size) |
458 | return 0; | |
1da177e4 LT |
459 | } |
460 | e = (struct arpt_entry *) | |
31836064 | 461 | (entry0 + newpos); |
1da177e4 LT |
462 | e->counters.pcnt = pos; |
463 | pos = newpos; | |
464 | } | |
465 | } | |
466 | next: | |
467 | duprintf("Finished chain %u\n", hook); | |
468 | } | |
469 | return 1; | |
470 | } | |
471 | ||
fb5b6095 PM |
472 | static inline int check_target(struct arpt_entry *e, const char *name) |
473 | { | |
87a2e70d | 474 | struct xt_entry_target *t = arpt_get_target(e); |
fb5b6095 | 475 | int ret; |
af5d6dc2 JE |
476 | struct xt_tgchk_param par = { |
477 | .table = name, | |
478 | .entryinfo = e, | |
479 | .target = t->u.kernel.target, | |
480 | .targinfo = t->data, | |
481 | .hook_mask = e->comefrom, | |
916a917d | 482 | .family = NFPROTO_ARP, |
af5d6dc2 JE |
483 | }; |
484 | ||
916a917d | 485 | ret = xt_check_target(&par, t->u.target_size - sizeof(*t), 0, false); |
367c6790 | 486 | if (ret < 0) { |
fb5b6095 PM |
487 | duprintf("arp_tables: check failed for `%s'.\n", |
488 | t->u.kernel.target->name); | |
367c6790 | 489 | return ret; |
fb5b6095 | 490 | } |
367c6790 | 491 | return 0; |
fb5b6095 PM |
492 | } |
493 | ||
494 | static inline int | |
0559518b | 495 | find_check_entry(struct arpt_entry *e, const char *name, unsigned int size) |
fb5b6095 | 496 | { |
87a2e70d | 497 | struct xt_entry_target *t; |
95eea855 | 498 | struct xt_target *target; |
fb5b6095 PM |
499 | int ret; |
500 | ||
fb5b6095 | 501 | t = arpt_get_target(e); |
d2a7b6ba JE |
502 | target = xt_request_find_target(NFPROTO_ARP, t->u.user.name, |
503 | t->u.user.revision); | |
504 | if (IS_ERR(target)) { | |
fb5b6095 | 505 | duprintf("find_check_entry: `%s' not found\n", t->u.user.name); |
d2a7b6ba | 506 | ret = PTR_ERR(target); |
1da177e4 LT |
507 | goto out; |
508 | } | |
1da177e4 | 509 | t->u.kernel.target = target; |
1da177e4 | 510 | |
fb5b6095 | 511 | ret = check_target(e, name); |
3cdc7c95 PM |
512 | if (ret) |
513 | goto err; | |
1da177e4 | 514 | return 0; |
3cdc7c95 PM |
515 | err: |
516 | module_put(t->u.kernel.target->me); | |
1da177e4 LT |
517 | out: |
518 | return ret; | |
519 | } | |
520 | ||
d5d1baa1 | 521 | static bool check_underflow(const struct arpt_entry *e) |
e2fe35c1 | 522 | { |
87a2e70d | 523 | const struct xt_entry_target *t; |
e2fe35c1 JE |
524 | unsigned int verdict; |
525 | ||
1ee858dd | 526 | if (!unconditional(e)) |
e2fe35c1 | 527 | return false; |
d5d1baa1 | 528 | t = arpt_get_target_c(e); |
e2fe35c1 JE |
529 | if (strcmp(t->u.user.name, XT_STANDARD_TARGET) != 0) |
530 | return false; | |
87a2e70d | 531 | verdict = ((struct xt_standard_target *)t)->verdict; |
e2fe35c1 JE |
532 | verdict = -verdict - 1; |
533 | return verdict == NF_DROP || verdict == NF_ACCEPT; | |
534 | } | |
535 | ||
1da177e4 | 536 | static inline int check_entry_size_and_hooks(struct arpt_entry *e, |
2e4e6a17 | 537 | struct xt_table_info *newinfo, |
d5d1baa1 JE |
538 | const unsigned char *base, |
539 | const unsigned char *limit, | |
1da177e4 LT |
540 | const unsigned int *hook_entries, |
541 | const unsigned int *underflows, | |
0559518b | 542 | unsigned int valid_hooks) |
1da177e4 LT |
543 | { |
544 | unsigned int h; | |
0608074c | 545 | int err; |
1da177e4 | 546 | |
3666ed1c | 547 | if ((unsigned long)e % __alignof__(struct arpt_entry) != 0 || |
74afad87 FW |
548 | (unsigned char *)e + sizeof(struct arpt_entry) >= limit || |
549 | (unsigned char *)e + e->next_offset > limit) { | |
1da177e4 LT |
550 | duprintf("Bad offset %p\n", e); |
551 | return -EINVAL; | |
552 | } | |
553 | ||
554 | if (e->next_offset | |
87a2e70d | 555 | < sizeof(struct arpt_entry) + sizeof(struct xt_entry_target)) { |
1da177e4 LT |
556 | duprintf("checking: element %p size %u\n", |
557 | e, e->next_offset); | |
558 | return -EINVAL; | |
559 | } | |
560 | ||
ea878a44 FW |
561 | if (!arp_checkentry(&e->arp)) |
562 | return -EINVAL; | |
563 | ||
71f72bbf FW |
564 | err = xt_check_entry_offsets(e, e->elems, e->target_offset, |
565 | e->next_offset); | |
0608074c FW |
566 | if (err) |
567 | return err; | |
568 | ||
1da177e4 LT |
569 | /* Check hooks & underflows */ |
570 | for (h = 0; h < NF_ARP_NUMHOOKS; h++) { | |
a7d51738 JE |
571 | if (!(valid_hooks & (1 << h))) |
572 | continue; | |
1da177e4 LT |
573 | if ((unsigned char *)e - base == hook_entries[h]) |
574 | newinfo->hook_entry[h] = hook_entries[h]; | |
90e7d4ab | 575 | if ((unsigned char *)e - base == underflows[h]) { |
e2fe35c1 | 576 | if (!check_underflow(e)) { |
1ee858dd FW |
577 | pr_debug("Underflows must be unconditional and " |
578 | "use the STANDARD target with " | |
579 | "ACCEPT/DROP\n"); | |
90e7d4ab JE |
580 | return -EINVAL; |
581 | } | |
1da177e4 | 582 | newinfo->underflow[h] = underflows[h]; |
90e7d4ab | 583 | } |
1da177e4 LT |
584 | } |
585 | ||
1da177e4 | 586 | /* Clear counters and comefrom */ |
2e4e6a17 | 587 | e->counters = ((struct xt_counters) { 0, 0 }); |
1da177e4 | 588 | e->comefrom = 0; |
1da177e4 LT |
589 | return 0; |
590 | } | |
591 | ||
0559518b | 592 | static inline void cleanup_entry(struct arpt_entry *e) |
1da177e4 | 593 | { |
a2df1648 | 594 | struct xt_tgdtor_param par; |
87a2e70d | 595 | struct xt_entry_target *t; |
1da177e4 | 596 | |
1da177e4 | 597 | t = arpt_get_target(e); |
a2df1648 JE |
598 | par.target = t->u.kernel.target; |
599 | par.targinfo = t->data; | |
916a917d | 600 | par.family = NFPROTO_ARP; |
a2df1648 JE |
601 | if (par.target->destroy != NULL) |
602 | par.target->destroy(&par); | |
603 | module_put(par.target->me); | |
1da177e4 LT |
604 | } |
605 | ||
606 | /* Checks and translates the user-supplied table segment (held in | |
607 | * newinfo). | |
608 | */ | |
0f234214 JE |
609 | static int translate_table(struct xt_table_info *newinfo, void *entry0, |
610 | const struct arpt_replace *repl) | |
1da177e4 | 611 | { |
72b2b1dd | 612 | struct arpt_entry *iter; |
1da177e4 | 613 | unsigned int i; |
72b2b1dd | 614 | int ret = 0; |
1da177e4 | 615 | |
0f234214 JE |
616 | newinfo->size = repl->size; |
617 | newinfo->number = repl->num_entries; | |
1da177e4 LT |
618 | |
619 | /* Init all hooks to impossible value. */ | |
620 | for (i = 0; i < NF_ARP_NUMHOOKS; i++) { | |
621 | newinfo->hook_entry[i] = 0xFFFFFFFF; | |
622 | newinfo->underflow[i] = 0xFFFFFFFF; | |
623 | } | |
624 | ||
625 | duprintf("translate_table: size %u\n", newinfo->size); | |
626 | i = 0; | |
627 | ||
628 | /* Walk through entries, checking offsets. */ | |
72b2b1dd JE |
629 | xt_entry_foreach(iter, entry0, newinfo->size) { |
630 | ret = check_entry_size_and_hooks(iter, newinfo, entry0, | |
6b4ff2d7 JE |
631 | entry0 + repl->size, |
632 | repl->hook_entry, | |
633 | repl->underflow, | |
634 | repl->valid_hooks); | |
72b2b1dd JE |
635 | if (ret != 0) |
636 | break; | |
0559518b | 637 | ++i; |
f3c5c1bf JE |
638 | if (strcmp(arpt_get_target(iter)->u.user.name, |
639 | XT_ERROR_TARGET) == 0) | |
640 | ++newinfo->stacksize; | |
72b2b1dd | 641 | } |
1da177e4 LT |
642 | duprintf("translate_table: ARPT_ENTRY_ITERATE gives %d\n", ret); |
643 | if (ret != 0) | |
644 | return ret; | |
645 | ||
0f234214 | 646 | if (i != repl->num_entries) { |
1da177e4 | 647 | duprintf("translate_table: %u not %u entries\n", |
0f234214 | 648 | i, repl->num_entries); |
1da177e4 LT |
649 | return -EINVAL; |
650 | } | |
651 | ||
652 | /* Check hooks all assigned */ | |
653 | for (i = 0; i < NF_ARP_NUMHOOKS; i++) { | |
654 | /* Only hooks which are valid */ | |
0f234214 | 655 | if (!(repl->valid_hooks & (1 << i))) |
1da177e4 LT |
656 | continue; |
657 | if (newinfo->hook_entry[i] == 0xFFFFFFFF) { | |
658 | duprintf("Invalid hook entry %u %u\n", | |
0f234214 | 659 | i, repl->hook_entry[i]); |
1da177e4 LT |
660 | return -EINVAL; |
661 | } | |
662 | if (newinfo->underflow[i] == 0xFFFFFFFF) { | |
663 | duprintf("Invalid underflow %u %u\n", | |
0f234214 | 664 | i, repl->underflow[i]); |
1da177e4 LT |
665 | return -EINVAL; |
666 | } | |
667 | } | |
668 | ||
82e2616a | 669 | if (!mark_source_chains(newinfo, repl->valid_hooks, entry0)) |
74c9c0c1 | 670 | return -ELOOP; |
74c9c0c1 | 671 | |
1da177e4 LT |
672 | /* Finally, each sanity check must pass */ |
673 | i = 0; | |
72b2b1dd | 674 | xt_entry_foreach(iter, entry0, newinfo->size) { |
0f234214 | 675 | ret = find_check_entry(iter, repl->name, repl->size); |
72b2b1dd JE |
676 | if (ret != 0) |
677 | break; | |
0559518b | 678 | ++i; |
72b2b1dd | 679 | } |
1da177e4 | 680 | |
74c9c0c1 | 681 | if (ret != 0) { |
0559518b JE |
682 | xt_entry_foreach(iter, entry0, newinfo->size) { |
683 | if (i-- == 0) | |
72b2b1dd | 684 | break; |
0559518b JE |
685 | cleanup_entry(iter); |
686 | } | |
74c9c0c1 | 687 | return ret; |
1da177e4 LT |
688 | } |
689 | ||
690 | /* And one copy for every other CPU */ | |
6f912042 | 691 | for_each_possible_cpu(i) { |
31836064 ED |
692 | if (newinfo->entries[i] && newinfo->entries[i] != entry0) |
693 | memcpy(newinfo->entries[i], entry0, newinfo->size); | |
1da177e4 LT |
694 | } |
695 | ||
696 | return ret; | |
697 | } | |
698 | ||
2e4e6a17 HW |
699 | static void get_counters(const struct xt_table_info *t, |
700 | struct xt_counters counters[]) | |
1da177e4 | 701 | { |
72b2b1dd | 702 | struct arpt_entry *iter; |
1da177e4 LT |
703 | unsigned int cpu; |
704 | unsigned int i; | |
705 | ||
6f912042 | 706 | for_each_possible_cpu(cpu) { |
7f5c6d4f | 707 | seqcount_t *s = &per_cpu(xt_recseq, cpu); |
83723d60 | 708 | |
1da177e4 | 709 | i = 0; |
0559518b | 710 | xt_entry_foreach(iter, t->entries[cpu], t->size) { |
83723d60 ED |
711 | u64 bcnt, pcnt; |
712 | unsigned int start; | |
713 | ||
714 | do { | |
7f5c6d4f | 715 | start = read_seqcount_begin(s); |
83723d60 ED |
716 | bcnt = iter->counters.bcnt; |
717 | pcnt = iter->counters.pcnt; | |
7f5c6d4f | 718 | } while (read_seqcount_retry(s, start)); |
83723d60 ED |
719 | |
720 | ADD_COUNTER(counters[i], bcnt, pcnt); | |
0559518b JE |
721 | ++i; |
722 | } | |
1da177e4 | 723 | } |
78454473 SH |
724 | } |
725 | ||
d5d1baa1 | 726 | static struct xt_counters *alloc_counters(const struct xt_table *table) |
1da177e4 | 727 | { |
27e2c26b | 728 | unsigned int countersize; |
2e4e6a17 | 729 | struct xt_counters *counters; |
d5d1baa1 | 730 | const struct xt_table_info *private = table->private; |
1da177e4 LT |
731 | |
732 | /* We need atomic snapshot of counters: rest doesn't change | |
733 | * (other than comefrom, which userspace doesn't care | |
734 | * about). | |
735 | */ | |
2e4e6a17 | 736 | countersize = sizeof(struct xt_counters) * private->number; |
83723d60 | 737 | counters = vzalloc(countersize); |
1da177e4 LT |
738 | |
739 | if (counters == NULL) | |
942e4a2b | 740 | return ERR_PTR(-ENOMEM); |
78454473 | 741 | |
942e4a2b | 742 | get_counters(private, counters); |
1da177e4 | 743 | |
27e2c26b PM |
744 | return counters; |
745 | } | |
746 | ||
747 | static int copy_entries_to_user(unsigned int total_size, | |
d5d1baa1 | 748 | const struct xt_table *table, |
27e2c26b PM |
749 | void __user *userptr) |
750 | { | |
751 | unsigned int off, num; | |
d5d1baa1 | 752 | const struct arpt_entry *e; |
27e2c26b | 753 | struct xt_counters *counters; |
4abff077 | 754 | struct xt_table_info *private = table->private; |
27e2c26b PM |
755 | int ret = 0; |
756 | void *loc_cpu_entry; | |
757 | ||
758 | counters = alloc_counters(table); | |
759 | if (IS_ERR(counters)) | |
760 | return PTR_ERR(counters); | |
761 | ||
2e4e6a17 | 762 | loc_cpu_entry = private->entries[raw_smp_processor_id()]; |
31836064 ED |
763 | /* ... then copy entire thing ... */ |
764 | if (copy_to_user(userptr, loc_cpu_entry, total_size) != 0) { | |
1da177e4 LT |
765 | ret = -EFAULT; |
766 | goto free_counters; | |
767 | } | |
768 | ||
769 | /* FIXME: use iterator macros --RR */ | |
770 | /* ... then go back and fix counters and names */ | |
771 | for (off = 0, num = 0; off < total_size; off += e->next_offset, num++){ | |
87a2e70d | 772 | const struct xt_entry_target *t; |
1da177e4 | 773 | |
31836064 | 774 | e = (struct arpt_entry *)(loc_cpu_entry + off); |
1da177e4 LT |
775 | if (copy_to_user(userptr + off |
776 | + offsetof(struct arpt_entry, counters), | |
777 | &counters[num], | |
778 | sizeof(counters[num])) != 0) { | |
779 | ret = -EFAULT; | |
780 | goto free_counters; | |
781 | } | |
782 | ||
d5d1baa1 | 783 | t = arpt_get_target_c(e); |
1da177e4 | 784 | if (copy_to_user(userptr + off + e->target_offset |
87a2e70d | 785 | + offsetof(struct xt_entry_target, |
1da177e4 LT |
786 | u.user.name), |
787 | t->u.kernel.target->name, | |
788 | strlen(t->u.kernel.target->name)+1) != 0) { | |
789 | ret = -EFAULT; | |
790 | goto free_counters; | |
791 | } | |
792 | } | |
793 | ||
794 | free_counters: | |
795 | vfree(counters); | |
796 | return ret; | |
797 | } | |
798 | ||
d6a2ba07 | 799 | #ifdef CONFIG_COMPAT |
739674fb | 800 | static void compat_standard_from_user(void *dst, const void *src) |
d6a2ba07 PM |
801 | { |
802 | int v = *(compat_int_t *)src; | |
803 | ||
804 | if (v > 0) | |
ee999d8b | 805 | v += xt_compat_calc_jump(NFPROTO_ARP, v); |
d6a2ba07 PM |
806 | memcpy(dst, &v, sizeof(v)); |
807 | } | |
808 | ||
739674fb | 809 | static int compat_standard_to_user(void __user *dst, const void *src) |
d6a2ba07 PM |
810 | { |
811 | compat_int_t cv = *(int *)src; | |
812 | ||
813 | if (cv > 0) | |
ee999d8b | 814 | cv -= xt_compat_calc_jump(NFPROTO_ARP, cv); |
d6a2ba07 PM |
815 | return copy_to_user(dst, &cv, sizeof(cv)) ? -EFAULT : 0; |
816 | } | |
817 | ||
d5d1baa1 | 818 | static int compat_calc_entry(const struct arpt_entry *e, |
d6a2ba07 | 819 | const struct xt_table_info *info, |
d5d1baa1 | 820 | const void *base, struct xt_table_info *newinfo) |
d6a2ba07 | 821 | { |
87a2e70d | 822 | const struct xt_entry_target *t; |
d6a2ba07 PM |
823 | unsigned int entry_offset; |
824 | int off, i, ret; | |
825 | ||
826 | off = sizeof(struct arpt_entry) - sizeof(struct compat_arpt_entry); | |
827 | entry_offset = (void *)e - base; | |
828 | ||
d5d1baa1 | 829 | t = arpt_get_target_c(e); |
d6a2ba07 PM |
830 | off += xt_compat_target_offset(t->u.kernel.target); |
831 | newinfo->size -= off; | |
ee999d8b | 832 | ret = xt_compat_add_offset(NFPROTO_ARP, entry_offset, off); |
d6a2ba07 PM |
833 | if (ret) |
834 | return ret; | |
835 | ||
836 | for (i = 0; i < NF_ARP_NUMHOOKS; i++) { | |
837 | if (info->hook_entry[i] && | |
838 | (e < (struct arpt_entry *)(base + info->hook_entry[i]))) | |
839 | newinfo->hook_entry[i] -= off; | |
840 | if (info->underflow[i] && | |
841 | (e < (struct arpt_entry *)(base + info->underflow[i]))) | |
842 | newinfo->underflow[i] -= off; | |
843 | } | |
844 | return 0; | |
845 | } | |
846 | ||
847 | static int compat_table_info(const struct xt_table_info *info, | |
848 | struct xt_table_info *newinfo) | |
849 | { | |
72b2b1dd | 850 | struct arpt_entry *iter; |
d6a2ba07 | 851 | void *loc_cpu_entry; |
0559518b | 852 | int ret; |
d6a2ba07 PM |
853 | |
854 | if (!newinfo || !info) | |
855 | return -EINVAL; | |
856 | ||
857 | /* we dont care about newinfo->entries[] */ | |
858 | memcpy(newinfo, info, offsetof(struct xt_table_info, entries)); | |
859 | newinfo->initial_entries = 0; | |
860 | loc_cpu_entry = info->entries[raw_smp_processor_id()]; | |
255d0dc3 | 861 | xt_compat_init_offsets(NFPROTO_ARP, info->number); |
72b2b1dd JE |
862 | xt_entry_foreach(iter, loc_cpu_entry, info->size) { |
863 | ret = compat_calc_entry(iter, info, loc_cpu_entry, newinfo); | |
864 | if (ret != 0) | |
0559518b | 865 | return ret; |
72b2b1dd | 866 | } |
0559518b | 867 | return 0; |
d6a2ba07 PM |
868 | } |
869 | #endif | |
870 | ||
d5d1baa1 JE |
871 | static int get_info(struct net *net, void __user *user, |
872 | const int *len, int compat) | |
41acd975 | 873 | { |
12b00c2c | 874 | char name[XT_TABLE_MAXNAMELEN]; |
4abff077 | 875 | struct xt_table *t; |
41acd975 PM |
876 | int ret; |
877 | ||
878 | if (*len != sizeof(struct arpt_getinfo)) { | |
879 | duprintf("length %u != %Zu\n", *len, | |
880 | sizeof(struct arpt_getinfo)); | |
881 | return -EINVAL; | |
882 | } | |
883 | ||
884 | if (copy_from_user(name, user, sizeof(name)) != 0) | |
885 | return -EFAULT; | |
886 | ||
12b00c2c | 887 | name[XT_TABLE_MAXNAMELEN-1] = '\0'; |
d6a2ba07 PM |
888 | #ifdef CONFIG_COMPAT |
889 | if (compat) | |
ee999d8b | 890 | xt_compat_lock(NFPROTO_ARP); |
d6a2ba07 | 891 | #endif |
ee999d8b | 892 | t = try_then_request_module(xt_find_table_lock(net, NFPROTO_ARP, name), |
41acd975 | 893 | "arptable_%s", name); |
0cc8d8df | 894 | if (!IS_ERR_OR_NULL(t)) { |
41acd975 | 895 | struct arpt_getinfo info; |
5452e425 | 896 | const struct xt_table_info *private = t->private; |
d6a2ba07 | 897 | #ifdef CONFIG_COMPAT |
14c7dbe0 AD |
898 | struct xt_table_info tmp; |
899 | ||
d6a2ba07 | 900 | if (compat) { |
d6a2ba07 | 901 | ret = compat_table_info(private, &tmp); |
ee999d8b | 902 | xt_compat_flush_offsets(NFPROTO_ARP); |
d6a2ba07 PM |
903 | private = &tmp; |
904 | } | |
905 | #endif | |
1a8b7a67 | 906 | memset(&info, 0, sizeof(info)); |
41acd975 PM |
907 | info.valid_hooks = t->valid_hooks; |
908 | memcpy(info.hook_entry, private->hook_entry, | |
909 | sizeof(info.hook_entry)); | |
910 | memcpy(info.underflow, private->underflow, | |
911 | sizeof(info.underflow)); | |
912 | info.num_entries = private->number; | |
913 | info.size = private->size; | |
914 | strcpy(info.name, name); | |
915 | ||
916 | if (copy_to_user(user, &info, *len) != 0) | |
917 | ret = -EFAULT; | |
918 | else | |
919 | ret = 0; | |
920 | xt_table_unlock(t); | |
921 | module_put(t->me); | |
922 | } else | |
923 | ret = t ? PTR_ERR(t) : -ENOENT; | |
d6a2ba07 PM |
924 | #ifdef CONFIG_COMPAT |
925 | if (compat) | |
ee999d8b | 926 | xt_compat_unlock(NFPROTO_ARP); |
d6a2ba07 | 927 | #endif |
41acd975 PM |
928 | return ret; |
929 | } | |
930 | ||
79df341a | 931 | static int get_entries(struct net *net, struct arpt_get_entries __user *uptr, |
d5d1baa1 | 932 | const int *len) |
1da177e4 LT |
933 | { |
934 | int ret; | |
11f6dff8 | 935 | struct arpt_get_entries get; |
4abff077 | 936 | struct xt_table *t; |
1da177e4 | 937 | |
11f6dff8 PM |
938 | if (*len < sizeof(get)) { |
939 | duprintf("get_entries: %u < %Zu\n", *len, sizeof(get)); | |
940 | return -EINVAL; | |
941 | } | |
942 | if (copy_from_user(&get, uptr, sizeof(get)) != 0) | |
943 | return -EFAULT; | |
944 | if (*len != sizeof(struct arpt_get_entries) + get.size) { | |
945 | duprintf("get_entries: %u != %Zu\n", *len, | |
946 | sizeof(struct arpt_get_entries) + get.size); | |
947 | return -EINVAL; | |
948 | } | |
949 | ||
ee999d8b | 950 | t = xt_find_table_lock(net, NFPROTO_ARP, get.name); |
0cc8d8df | 951 | if (!IS_ERR_OR_NULL(t)) { |
5452e425 JE |
952 | const struct xt_table_info *private = t->private; |
953 | ||
1da177e4 | 954 | duprintf("t->private->number = %u\n", |
2e4e6a17 | 955 | private->number); |
11f6dff8 | 956 | if (get.size == private->size) |
2e4e6a17 | 957 | ret = copy_entries_to_user(private->size, |
1da177e4 LT |
958 | t, uptr->entrytable); |
959 | else { | |
960 | duprintf("get_entries: I've got %u not %u!\n", | |
11f6dff8 | 961 | private->size, get.size); |
544473c1 | 962 | ret = -EAGAIN; |
1da177e4 | 963 | } |
6b7d31fc | 964 | module_put(t->me); |
2e4e6a17 | 965 | xt_table_unlock(t); |
1da177e4 | 966 | } else |
6b7d31fc | 967 | ret = t ? PTR_ERR(t) : -ENOENT; |
1da177e4 LT |
968 | |
969 | return ret; | |
970 | } | |
971 | ||
79df341a AD |
972 | static int __do_replace(struct net *net, const char *name, |
973 | unsigned int valid_hooks, | |
d6a2ba07 PM |
974 | struct xt_table_info *newinfo, |
975 | unsigned int num_counters, | |
976 | void __user *counters_ptr) | |
1da177e4 LT |
977 | { |
978 | int ret; | |
4abff077 | 979 | struct xt_table *t; |
d6a2ba07 | 980 | struct xt_table_info *oldinfo; |
2e4e6a17 | 981 | struct xt_counters *counters; |
d6a2ba07 | 982 | void *loc_cpu_old_entry; |
72b2b1dd | 983 | struct arpt_entry *iter; |
1da177e4 | 984 | |
d6a2ba07 | 985 | ret = 0; |
83723d60 | 986 | counters = vzalloc(num_counters * sizeof(struct xt_counters)); |
1da177e4 LT |
987 | if (!counters) { |
988 | ret = -ENOMEM; | |
d6a2ba07 | 989 | goto out; |
1da177e4 | 990 | } |
1da177e4 | 991 | |
ee999d8b | 992 | t = try_then_request_module(xt_find_table_lock(net, NFPROTO_ARP, name), |
d6a2ba07 | 993 | "arptable_%s", name); |
0cc8d8df | 994 | if (IS_ERR_OR_NULL(t)) { |
6b7d31fc | 995 | ret = t ? PTR_ERR(t) : -ENOENT; |
1da177e4 | 996 | goto free_newinfo_counters_untrans; |
6b7d31fc | 997 | } |
1da177e4 LT |
998 | |
999 | /* You lied! */ | |
d6a2ba07 | 1000 | if (valid_hooks != t->valid_hooks) { |
1da177e4 | 1001 | duprintf("Valid hook crap: %08X vs %08X\n", |
d6a2ba07 | 1002 | valid_hooks, t->valid_hooks); |
1da177e4 | 1003 | ret = -EINVAL; |
6b7d31fc | 1004 | goto put_module; |
1da177e4 LT |
1005 | } |
1006 | ||
d6a2ba07 | 1007 | oldinfo = xt_replace_table(t, num_counters, newinfo, &ret); |
1da177e4 LT |
1008 | if (!oldinfo) |
1009 | goto put_module; | |
1010 | ||
1011 | /* Update module usage count based on number of rules */ | |
1012 | duprintf("do_replace: oldnum=%u, initnum=%u, newnum=%u\n", | |
1013 | oldinfo->number, oldinfo->initial_entries, newinfo->number); | |
e905a9ed YH |
1014 | if ((oldinfo->number > oldinfo->initial_entries) || |
1015 | (newinfo->number <= oldinfo->initial_entries)) | |
1da177e4 LT |
1016 | module_put(t->me); |
1017 | if ((oldinfo->number > oldinfo->initial_entries) && | |
1018 | (newinfo->number <= oldinfo->initial_entries)) | |
1019 | module_put(t->me); | |
1020 | ||
942e4a2b | 1021 | /* Get the old counters, and synchronize with replace */ |
1da177e4 | 1022 | get_counters(oldinfo, counters); |
942e4a2b | 1023 | |
1da177e4 | 1024 | /* Decrease module usage counts and free resource */ |
31836064 | 1025 | loc_cpu_old_entry = oldinfo->entries[raw_smp_processor_id()]; |
72b2b1dd | 1026 | xt_entry_foreach(iter, loc_cpu_old_entry, oldinfo->size) |
0559518b | 1027 | cleanup_entry(iter); |
31836064 | 1028 | |
2e4e6a17 | 1029 | xt_free_table_info(oldinfo); |
d6a2ba07 | 1030 | if (copy_to_user(counters_ptr, counters, |
c5e4ef49 TG |
1031 | sizeof(struct xt_counters) * num_counters) != 0) { |
1032 | /* Silent error, can't fail, new table is already in place */ | |
1033 | net_warn_ratelimited("arptables: counters copy to user failed while replacing table\n"); | |
1034 | } | |
1da177e4 | 1035 | vfree(counters); |
2e4e6a17 | 1036 | xt_table_unlock(t); |
1da177e4 LT |
1037 | return ret; |
1038 | ||
1039 | put_module: | |
1040 | module_put(t->me); | |
2e4e6a17 | 1041 | xt_table_unlock(t); |
1da177e4 | 1042 | free_newinfo_counters_untrans: |
1da177e4 | 1043 | vfree(counters); |
d6a2ba07 PM |
1044 | out: |
1045 | return ret; | |
1046 | } | |
1047 | ||
d5d1baa1 JE |
1048 | static int do_replace(struct net *net, const void __user *user, |
1049 | unsigned int len) | |
d6a2ba07 PM |
1050 | { |
1051 | int ret; | |
1052 | struct arpt_replace tmp; | |
1053 | struct xt_table_info *newinfo; | |
1054 | void *loc_cpu_entry; | |
72b2b1dd | 1055 | struct arpt_entry *iter; |
d6a2ba07 PM |
1056 | |
1057 | if (copy_from_user(&tmp, user, sizeof(tmp)) != 0) | |
1058 | return -EFAULT; | |
1059 | ||
1060 | /* overflow check */ | |
1061 | if (tmp.num_counters >= INT_MAX / sizeof(struct xt_counters)) | |
1062 | return -ENOMEM; | |
42eab94f | 1063 | tmp.name[sizeof(tmp.name)-1] = 0; |
d6a2ba07 PM |
1064 | |
1065 | newinfo = xt_alloc_table_info(tmp.size); | |
1066 | if (!newinfo) | |
1067 | return -ENOMEM; | |
1068 | ||
1069 | /* choose the copy that is on our node/cpu */ | |
1070 | loc_cpu_entry = newinfo->entries[raw_smp_processor_id()]; | |
1071 | if (copy_from_user(loc_cpu_entry, user + sizeof(tmp), | |
1072 | tmp.size) != 0) { | |
1073 | ret = -EFAULT; | |
1074 | goto free_newinfo; | |
1075 | } | |
1076 | ||
0f234214 | 1077 | ret = translate_table(newinfo, loc_cpu_entry, &tmp); |
d6a2ba07 PM |
1078 | if (ret != 0) |
1079 | goto free_newinfo; | |
1080 | ||
1081 | duprintf("arp_tables: Translated table\n"); | |
1082 | ||
79df341a | 1083 | ret = __do_replace(net, tmp.name, tmp.valid_hooks, newinfo, |
d6a2ba07 PM |
1084 | tmp.num_counters, tmp.counters); |
1085 | if (ret) | |
1086 | goto free_newinfo_untrans; | |
1087 | return 0; | |
1088 | ||
1089 | free_newinfo_untrans: | |
72b2b1dd | 1090 | xt_entry_foreach(iter, loc_cpu_entry, newinfo->size) |
0559518b | 1091 | cleanup_entry(iter); |
1da177e4 | 1092 | free_newinfo: |
2e4e6a17 | 1093 | xt_free_table_info(newinfo); |
1da177e4 LT |
1094 | return ret; |
1095 | } | |
1096 | ||
d5d1baa1 JE |
1097 | static int do_add_counters(struct net *net, const void __user *user, |
1098 | unsigned int len, int compat) | |
1da177e4 | 1099 | { |
942e4a2b | 1100 | unsigned int i, curcpu; |
d6a2ba07 PM |
1101 | struct xt_counters_info tmp; |
1102 | struct xt_counters *paddc; | |
1103 | unsigned int num_counters; | |
5452e425 | 1104 | const char *name; |
d6a2ba07 PM |
1105 | int size; |
1106 | void *ptmp; | |
4abff077 | 1107 | struct xt_table *t; |
5452e425 | 1108 | const struct xt_table_info *private; |
6b7d31fc | 1109 | int ret = 0; |
31836064 | 1110 | void *loc_cpu_entry; |
72b2b1dd | 1111 | struct arpt_entry *iter; |
7f5c6d4f | 1112 | unsigned int addend; |
d6a2ba07 PM |
1113 | #ifdef CONFIG_COMPAT |
1114 | struct compat_xt_counters_info compat_tmp; | |
1da177e4 | 1115 | |
d6a2ba07 PM |
1116 | if (compat) { |
1117 | ptmp = &compat_tmp; | |
1118 | size = sizeof(struct compat_xt_counters_info); | |
1119 | } else | |
1120 | #endif | |
1121 | { | |
1122 | ptmp = &tmp; | |
1123 | size = sizeof(struct xt_counters_info); | |
1124 | } | |
1125 | ||
1126 | if (copy_from_user(ptmp, user, size) != 0) | |
1da177e4 LT |
1127 | return -EFAULT; |
1128 | ||
d6a2ba07 PM |
1129 | #ifdef CONFIG_COMPAT |
1130 | if (compat) { | |
1131 | num_counters = compat_tmp.num_counters; | |
1132 | name = compat_tmp.name; | |
1133 | } else | |
1134 | #endif | |
1135 | { | |
1136 | num_counters = tmp.num_counters; | |
1137 | name = tmp.name; | |
1138 | } | |
1139 | ||
1140 | if (len != size + num_counters * sizeof(struct xt_counters)) | |
1da177e4 LT |
1141 | return -EINVAL; |
1142 | ||
e12f8e29 | 1143 | paddc = vmalloc(len - size); |
1da177e4 LT |
1144 | if (!paddc) |
1145 | return -ENOMEM; | |
1146 | ||
d6a2ba07 | 1147 | if (copy_from_user(paddc, user + size, len - size) != 0) { |
1da177e4 LT |
1148 | ret = -EFAULT; |
1149 | goto free; | |
1150 | } | |
1151 | ||
ee999d8b | 1152 | t = xt_find_table_lock(net, NFPROTO_ARP, name); |
0cc8d8df | 1153 | if (IS_ERR_OR_NULL(t)) { |
6b7d31fc | 1154 | ret = t ? PTR_ERR(t) : -ENOENT; |
1da177e4 | 1155 | goto free; |
6b7d31fc | 1156 | } |
1da177e4 | 1157 | |
942e4a2b | 1158 | local_bh_disable(); |
2e4e6a17 | 1159 | private = t->private; |
d6a2ba07 | 1160 | if (private->number != num_counters) { |
1da177e4 LT |
1161 | ret = -EINVAL; |
1162 | goto unlock_up_free; | |
1163 | } | |
1164 | ||
1165 | i = 0; | |
31836064 | 1166 | /* Choose the copy that is on our node */ |
942e4a2b SH |
1167 | curcpu = smp_processor_id(); |
1168 | loc_cpu_entry = private->entries[curcpu]; | |
7f5c6d4f | 1169 | addend = xt_write_recseq_begin(); |
0559518b JE |
1170 | xt_entry_foreach(iter, loc_cpu_entry, private->size) { |
1171 | ADD_COUNTER(iter->counters, paddc[i].bcnt, paddc[i].pcnt); | |
1172 | ++i; | |
1173 | } | |
7f5c6d4f | 1174 | xt_write_recseq_end(addend); |
1da177e4 | 1175 | unlock_up_free: |
942e4a2b | 1176 | local_bh_enable(); |
2e4e6a17 | 1177 | xt_table_unlock(t); |
6b7d31fc | 1178 | module_put(t->me); |
1da177e4 LT |
1179 | free: |
1180 | vfree(paddc); | |
1181 | ||
1182 | return ret; | |
1183 | } | |
1184 | ||
d6a2ba07 | 1185 | #ifdef CONFIG_COMPAT |
b6694fc6 FW |
1186 | struct compat_arpt_replace { |
1187 | char name[XT_TABLE_MAXNAMELEN]; | |
1188 | u32 valid_hooks; | |
1189 | u32 num_entries; | |
1190 | u32 size; | |
1191 | u32 hook_entry[NF_ARP_NUMHOOKS]; | |
1192 | u32 underflow[NF_ARP_NUMHOOKS]; | |
1193 | u32 num_counters; | |
1194 | compat_uptr_t counters; | |
1195 | struct compat_arpt_entry entries[0]; | |
1196 | }; | |
1197 | ||
0559518b | 1198 | static inline void compat_release_entry(struct compat_arpt_entry *e) |
d6a2ba07 | 1199 | { |
87a2e70d | 1200 | struct xt_entry_target *t; |
d6a2ba07 | 1201 | |
d6a2ba07 PM |
1202 | t = compat_arpt_get_target(e); |
1203 | module_put(t->u.kernel.target->me); | |
d6a2ba07 PM |
1204 | } |
1205 | ||
1206 | static inline int | |
1207 | check_compat_entry_size_and_hooks(struct compat_arpt_entry *e, | |
1208 | struct xt_table_info *newinfo, | |
1209 | unsigned int *size, | |
d5d1baa1 JE |
1210 | const unsigned char *base, |
1211 | const unsigned char *limit, | |
1212 | const unsigned int *hook_entries, | |
b6694fc6 | 1213 | const unsigned int *underflows) |
d6a2ba07 | 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 | ||
ea878a44 FW |
1235 | if (!arp_checkentry(&e->arp)) |
1236 | return -EINVAL; | |
1237 | ||
71f72bbf | 1238 | ret = xt_compat_check_entry_offsets(e, e->elems, e->target_offset, |
30532332 | 1239 | e->next_offset); |
d6a2ba07 PM |
1240 | if (ret) |
1241 | return ret; | |
1242 | ||
1243 | off = sizeof(struct arpt_entry) - sizeof(struct compat_arpt_entry); | |
1244 | entry_offset = (void *)e - (void *)base; | |
1245 | ||
1246 | t = compat_arpt_get_target(e); | |
d2a7b6ba JE |
1247 | target = xt_request_find_target(NFPROTO_ARP, t->u.user.name, |
1248 | t->u.user.revision); | |
1249 | if (IS_ERR(target)) { | |
d6a2ba07 PM |
1250 | duprintf("check_compat_entry_size_and_hooks: `%s' not found\n", |
1251 | t->u.user.name); | |
d2a7b6ba | 1252 | ret = PTR_ERR(target); |
d6a2ba07 PM |
1253 | goto out; |
1254 | } | |
1255 | t->u.kernel.target = target; | |
1256 | ||
1257 | off += xt_compat_target_offset(target); | |
1258 | *size += off; | |
ee999d8b | 1259 | ret = xt_compat_add_offset(NFPROTO_ARP, entry_offset, off); |
d6a2ba07 PM |
1260 | if (ret) |
1261 | goto release_target; | |
1262 | ||
1263 | /* Check hooks & underflows */ | |
1264 | for (h = 0; h < NF_ARP_NUMHOOKS; h++) { | |
1265 | if ((unsigned char *)e - base == hook_entries[h]) | |
1266 | newinfo->hook_entry[h] = hook_entries[h]; | |
1267 | if ((unsigned char *)e - base == underflows[h]) | |
1268 | newinfo->underflow[h] = underflows[h]; | |
1269 | } | |
1270 | ||
1271 | /* Clear counters and comefrom */ | |
1272 | memset(&e->counters, 0, sizeof(e->counters)); | |
1273 | e->comefrom = 0; | |
d6a2ba07 PM |
1274 | return 0; |
1275 | ||
1276 | release_target: | |
1277 | module_put(t->u.kernel.target->me); | |
1278 | out: | |
1279 | return ret; | |
1280 | } | |
1281 | ||
fbe426f8 | 1282 | static void |
d6a2ba07 | 1283 | compat_copy_entry_from_user(struct compat_arpt_entry *e, void **dstptr, |
b6694fc6 | 1284 | unsigned int *size, |
d6a2ba07 PM |
1285 | struct xt_table_info *newinfo, unsigned char *base) |
1286 | { | |
87a2e70d | 1287 | struct xt_entry_target *t; |
d6a2ba07 PM |
1288 | struct xt_target *target; |
1289 | struct arpt_entry *de; | |
1290 | unsigned int origsize; | |
fbe426f8 | 1291 | int h; |
d6a2ba07 | 1292 | |
d6a2ba07 PM |
1293 | origsize = *size; |
1294 | de = (struct arpt_entry *)*dstptr; | |
1295 | memcpy(de, e, sizeof(struct arpt_entry)); | |
1296 | memcpy(&de->counters, &e->counters, sizeof(e->counters)); | |
1297 | ||
1298 | *dstptr += sizeof(struct arpt_entry); | |
1299 | *size += sizeof(struct arpt_entry) - sizeof(struct compat_arpt_entry); | |
1300 | ||
1301 | de->target_offset = e->target_offset - (origsize - *size); | |
1302 | t = compat_arpt_get_target(e); | |
1303 | target = t->u.kernel.target; | |
1304 | xt_compat_target_from_user(t, dstptr, size); | |
1305 | ||
1306 | de->next_offset = e->next_offset - (origsize - *size); | |
1307 | for (h = 0; h < NF_ARP_NUMHOOKS; h++) { | |
1308 | if ((unsigned char *)de - base < newinfo->hook_entry[h]) | |
1309 | newinfo->hook_entry[h] -= origsize - *size; | |
1310 | if ((unsigned char *)de - base < newinfo->underflow[h]) | |
1311 | newinfo->underflow[h] -= origsize - *size; | |
1312 | } | |
d6a2ba07 PM |
1313 | } |
1314 | ||
b6694fc6 | 1315 | static int translate_compat_table(struct xt_table_info **pinfo, |
d6a2ba07 | 1316 | void **pentry0, |
b6694fc6 | 1317 | const struct compat_arpt_replace *compatr) |
d6a2ba07 PM |
1318 | { |
1319 | unsigned int i, j; | |
1320 | struct xt_table_info *newinfo, *info; | |
1321 | void *pos, *entry0, *entry1; | |
72b2b1dd JE |
1322 | struct compat_arpt_entry *iter0; |
1323 | struct arpt_entry *iter1; | |
d6a2ba07 | 1324 | unsigned int size; |
72b2b1dd | 1325 | int ret = 0; |
d6a2ba07 PM |
1326 | |
1327 | info = *pinfo; | |
1328 | entry0 = *pentry0; | |
b6694fc6 FW |
1329 | size = compatr->size; |
1330 | info->number = compatr->num_entries; | |
d6a2ba07 PM |
1331 | |
1332 | /* Init all hooks to impossible value. */ | |
1333 | for (i = 0; i < NF_ARP_NUMHOOKS; i++) { | |
1334 | info->hook_entry[i] = 0xFFFFFFFF; | |
1335 | info->underflow[i] = 0xFFFFFFFF; | |
1336 | } | |
1337 | ||
1338 | duprintf("translate_compat_table: size %u\n", info->size); | |
1339 | j = 0; | |
ee999d8b | 1340 | xt_compat_lock(NFPROTO_ARP); |
b6694fc6 | 1341 | xt_compat_init_offsets(NFPROTO_ARP, compatr->num_entries); |
d6a2ba07 | 1342 | /* Walk through entries, checking offsets. */ |
b6694fc6 | 1343 | xt_entry_foreach(iter0, entry0, compatr->size) { |
72b2b1dd | 1344 | ret = check_compat_entry_size_and_hooks(iter0, info, &size, |
6b4ff2d7 | 1345 | entry0, |
b6694fc6 FW |
1346 | entry0 + compatr->size, |
1347 | compatr->hook_entry, | |
1348 | compatr->underflow); | |
72b2b1dd | 1349 | if (ret != 0) |
0559518b JE |
1350 | goto out_unlock; |
1351 | ++j; | |
72b2b1dd | 1352 | } |
d6a2ba07 PM |
1353 | |
1354 | ret = -EINVAL; | |
b6694fc6 | 1355 | if (j != compatr->num_entries) { |
d6a2ba07 | 1356 | duprintf("translate_compat_table: %u not %u entries\n", |
b6694fc6 | 1357 | j, compatr->num_entries); |
d6a2ba07 PM |
1358 | goto out_unlock; |
1359 | } | |
1360 | ||
1361 | /* Check hooks all assigned */ | |
1362 | for (i = 0; i < NF_ARP_NUMHOOKS; i++) { | |
1363 | /* Only hooks which are valid */ | |
b6694fc6 | 1364 | if (!(compatr->valid_hooks & (1 << i))) |
d6a2ba07 PM |
1365 | continue; |
1366 | if (info->hook_entry[i] == 0xFFFFFFFF) { | |
1367 | duprintf("Invalid hook entry %u %u\n", | |
b6694fc6 | 1368 | i, info->hook_entry[i]); |
d6a2ba07 PM |
1369 | goto out_unlock; |
1370 | } | |
1371 | if (info->underflow[i] == 0xFFFFFFFF) { | |
1372 | duprintf("Invalid underflow %u %u\n", | |
b6694fc6 | 1373 | i, info->underflow[i]); |
d6a2ba07 PM |
1374 | goto out_unlock; |
1375 | } | |
1376 | } | |
1377 | ||
1378 | ret = -ENOMEM; | |
1379 | newinfo = xt_alloc_table_info(size); | |
1380 | if (!newinfo) | |
1381 | goto out_unlock; | |
1382 | ||
b6694fc6 | 1383 | newinfo->number = compatr->num_entries; |
d6a2ba07 PM |
1384 | for (i = 0; i < NF_ARP_NUMHOOKS; i++) { |
1385 | newinfo->hook_entry[i] = info->hook_entry[i]; | |
1386 | newinfo->underflow[i] = info->underflow[i]; | |
1387 | } | |
1388 | entry1 = newinfo->entries[raw_smp_processor_id()]; | |
1389 | pos = entry1; | |
b6694fc6 | 1390 | size = compatr->size; |
fbe426f8 FW |
1391 | xt_entry_foreach(iter0, entry0, compatr->size) |
1392 | compat_copy_entry_from_user(iter0, &pos, &size, | |
1393 | newinfo, entry1); | |
ee999d8b JE |
1394 | xt_compat_flush_offsets(NFPROTO_ARP); |
1395 | xt_compat_unlock(NFPROTO_ARP); | |
d6a2ba07 PM |
1396 | |
1397 | ret = -ELOOP; | |
b6694fc6 | 1398 | if (!mark_source_chains(newinfo, compatr->valid_hooks, entry1)) |
d6a2ba07 PM |
1399 | goto free_newinfo; |
1400 | ||
1401 | i = 0; | |
72b2b1dd | 1402 | xt_entry_foreach(iter1, entry1, newinfo->size) { |
b6694fc6 | 1403 | ret = check_target(iter1, compatr->name); |
72b2b1dd JE |
1404 | if (ret != 0) |
1405 | break; | |
0559518b | 1406 | ++i; |
cca77b7c FW |
1407 | if (strcmp(arpt_get_target(iter1)->u.user.name, |
1408 | XT_ERROR_TARGET) == 0) | |
1409 | ++newinfo->stacksize; | |
72b2b1dd | 1410 | } |
d6a2ba07 | 1411 | if (ret) { |
72b2b1dd JE |
1412 | /* |
1413 | * The first i matches need cleanup_entry (calls ->destroy) | |
1414 | * because they had called ->check already. The other j-i | |
1415 | * entries need only release. | |
1416 | */ | |
1417 | int skip = i; | |
d6a2ba07 | 1418 | j -= i; |
72b2b1dd JE |
1419 | xt_entry_foreach(iter0, entry0, newinfo->size) { |
1420 | if (skip-- > 0) | |
1421 | continue; | |
0559518b | 1422 | if (j-- == 0) |
72b2b1dd | 1423 | break; |
0559518b | 1424 | compat_release_entry(iter0); |
72b2b1dd | 1425 | } |
0559518b JE |
1426 | xt_entry_foreach(iter1, entry1, newinfo->size) { |
1427 | if (i-- == 0) | |
72b2b1dd | 1428 | break; |
0559518b JE |
1429 | cleanup_entry(iter1); |
1430 | } | |
d6a2ba07 PM |
1431 | xt_free_table_info(newinfo); |
1432 | return ret; | |
1433 | } | |
1434 | ||
1435 | /* And one copy for every other CPU */ | |
1436 | for_each_possible_cpu(i) | |
1437 | if (newinfo->entries[i] && newinfo->entries[i] != entry1) | |
1438 | memcpy(newinfo->entries[i], entry1, newinfo->size); | |
1439 | ||
1440 | *pinfo = newinfo; | |
1441 | *pentry0 = entry1; | |
1442 | xt_free_table_info(info); | |
1443 | return 0; | |
1444 | ||
1445 | free_newinfo: | |
1446 | xt_free_table_info(newinfo); | |
1447 | out: | |
b6694fc6 | 1448 | xt_entry_foreach(iter0, entry0, compatr->size) { |
0559518b | 1449 | if (j-- == 0) |
72b2b1dd | 1450 | break; |
0559518b JE |
1451 | compat_release_entry(iter0); |
1452 | } | |
d6a2ba07 PM |
1453 | return ret; |
1454 | out_unlock: | |
ee999d8b JE |
1455 | xt_compat_flush_offsets(NFPROTO_ARP); |
1456 | xt_compat_unlock(NFPROTO_ARP); | |
d6a2ba07 PM |
1457 | goto out; |
1458 | } | |
1459 | ||
79df341a AD |
1460 | static int compat_do_replace(struct net *net, void __user *user, |
1461 | unsigned int len) | |
d6a2ba07 PM |
1462 | { |
1463 | int ret; | |
1464 | struct compat_arpt_replace tmp; | |
1465 | struct xt_table_info *newinfo; | |
1466 | void *loc_cpu_entry; | |
72b2b1dd | 1467 | struct arpt_entry *iter; |
d6a2ba07 PM |
1468 | |
1469 | if (copy_from_user(&tmp, user, sizeof(tmp)) != 0) | |
1470 | return -EFAULT; | |
1471 | ||
1472 | /* overflow check */ | |
1473 | if (tmp.size >= INT_MAX / num_possible_cpus()) | |
1474 | return -ENOMEM; | |
1475 | if (tmp.num_counters >= INT_MAX / sizeof(struct xt_counters)) | |
1476 | return -ENOMEM; | |
42eab94f | 1477 | tmp.name[sizeof(tmp.name)-1] = 0; |
d6a2ba07 PM |
1478 | |
1479 | newinfo = xt_alloc_table_info(tmp.size); | |
1480 | if (!newinfo) | |
1481 | return -ENOMEM; | |
1482 | ||
1483 | /* choose the copy that is on our node/cpu */ | |
1484 | loc_cpu_entry = newinfo->entries[raw_smp_processor_id()]; | |
1485 | if (copy_from_user(loc_cpu_entry, user + sizeof(tmp), tmp.size) != 0) { | |
1486 | ret = -EFAULT; | |
1487 | goto free_newinfo; | |
1488 | } | |
1489 | ||
b6694fc6 | 1490 | ret = translate_compat_table(&newinfo, &loc_cpu_entry, &tmp); |
d6a2ba07 PM |
1491 | if (ret != 0) |
1492 | goto free_newinfo; | |
1493 | ||
1494 | duprintf("compat_do_replace: Translated table\n"); | |
1495 | ||
79df341a | 1496 | ret = __do_replace(net, tmp.name, tmp.valid_hooks, newinfo, |
d6a2ba07 PM |
1497 | tmp.num_counters, compat_ptr(tmp.counters)); |
1498 | if (ret) | |
1499 | goto free_newinfo_untrans; | |
1500 | return 0; | |
1501 | ||
1502 | free_newinfo_untrans: | |
72b2b1dd | 1503 | xt_entry_foreach(iter, loc_cpu_entry, newinfo->size) |
0559518b | 1504 | cleanup_entry(iter); |
d6a2ba07 PM |
1505 | free_newinfo: |
1506 | xt_free_table_info(newinfo); | |
1507 | return ret; | |
1508 | } | |
1509 | ||
1510 | static int compat_do_arpt_set_ctl(struct sock *sk, int cmd, void __user *user, | |
1511 | unsigned int len) | |
1512 | { | |
1513 | int ret; | |
1514 | ||
52e804c6 | 1515 | if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) |
d6a2ba07 PM |
1516 | return -EPERM; |
1517 | ||
1518 | switch (cmd) { | |
1519 | case ARPT_SO_SET_REPLACE: | |
3b1e0a65 | 1520 | ret = compat_do_replace(sock_net(sk), user, len); |
d6a2ba07 PM |
1521 | break; |
1522 | ||
1523 | case ARPT_SO_SET_ADD_COUNTERS: | |
3b1e0a65 | 1524 | ret = do_add_counters(sock_net(sk), user, len, 1); |
d6a2ba07 PM |
1525 | break; |
1526 | ||
1527 | default: | |
1528 | duprintf("do_arpt_set_ctl: unknown request %i\n", cmd); | |
1529 | ret = -EINVAL; | |
1530 | } | |
1531 | ||
1532 | return ret; | |
1533 | } | |
1534 | ||
1535 | static int compat_copy_entry_to_user(struct arpt_entry *e, void __user **dstptr, | |
1536 | compat_uint_t *size, | |
1537 | struct xt_counters *counters, | |
0559518b | 1538 | unsigned int i) |
d6a2ba07 | 1539 | { |
87a2e70d | 1540 | struct xt_entry_target *t; |
d6a2ba07 PM |
1541 | struct compat_arpt_entry __user *ce; |
1542 | u_int16_t target_offset, next_offset; | |
1543 | compat_uint_t origsize; | |
1544 | int ret; | |
1545 | ||
d6a2ba07 PM |
1546 | origsize = *size; |
1547 | ce = (struct compat_arpt_entry __user *)*dstptr; | |
0559518b JE |
1548 | if (copy_to_user(ce, e, sizeof(struct arpt_entry)) != 0 || |
1549 | copy_to_user(&ce->counters, &counters[i], | |
1550 | sizeof(counters[i])) != 0) | |
1551 | return -EFAULT; | |
d6a2ba07 PM |
1552 | |
1553 | *dstptr += sizeof(struct compat_arpt_entry); | |
1554 | *size -= sizeof(struct arpt_entry) - sizeof(struct compat_arpt_entry); | |
1555 | ||
1556 | target_offset = e->target_offset - (origsize - *size); | |
1557 | ||
1558 | t = arpt_get_target(e); | |
1559 | ret = xt_compat_target_to_user(t, dstptr, size); | |
1560 | if (ret) | |
0559518b | 1561 | return ret; |
d6a2ba07 | 1562 | next_offset = e->next_offset - (origsize - *size); |
0559518b JE |
1563 | if (put_user(target_offset, &ce->target_offset) != 0 || |
1564 | put_user(next_offset, &ce->next_offset) != 0) | |
1565 | return -EFAULT; | |
d6a2ba07 | 1566 | return 0; |
d6a2ba07 PM |
1567 | } |
1568 | ||
1569 | static int compat_copy_entries_to_user(unsigned int total_size, | |
4abff077 | 1570 | struct xt_table *table, |
d6a2ba07 PM |
1571 | void __user *userptr) |
1572 | { | |
1573 | struct xt_counters *counters; | |
5452e425 | 1574 | const struct xt_table_info *private = table->private; |
d6a2ba07 PM |
1575 | void __user *pos; |
1576 | unsigned int size; | |
1577 | int ret = 0; | |
1578 | void *loc_cpu_entry; | |
1579 | unsigned int i = 0; | |
72b2b1dd | 1580 | struct arpt_entry *iter; |
d6a2ba07 PM |
1581 | |
1582 | counters = alloc_counters(table); | |
1583 | if (IS_ERR(counters)) | |
1584 | return PTR_ERR(counters); | |
1585 | ||
1586 | /* choose the copy on our node/cpu */ | |
1587 | loc_cpu_entry = private->entries[raw_smp_processor_id()]; | |
1588 | pos = userptr; | |
1589 | size = total_size; | |
72b2b1dd JE |
1590 | xt_entry_foreach(iter, loc_cpu_entry, total_size) { |
1591 | ret = compat_copy_entry_to_user(iter, &pos, | |
6b4ff2d7 | 1592 | &size, counters, i++); |
72b2b1dd JE |
1593 | if (ret != 0) |
1594 | break; | |
1595 | } | |
d6a2ba07 PM |
1596 | vfree(counters); |
1597 | return ret; | |
1598 | } | |
1599 | ||
1600 | struct compat_arpt_get_entries { | |
12b00c2c | 1601 | char name[XT_TABLE_MAXNAMELEN]; |
d6a2ba07 PM |
1602 | compat_uint_t size; |
1603 | struct compat_arpt_entry entrytable[0]; | |
1604 | }; | |
1605 | ||
79df341a AD |
1606 | static int compat_get_entries(struct net *net, |
1607 | struct compat_arpt_get_entries __user *uptr, | |
d6a2ba07 PM |
1608 | int *len) |
1609 | { | |
1610 | int ret; | |
1611 | struct compat_arpt_get_entries get; | |
4abff077 | 1612 | struct xt_table *t; |
d6a2ba07 PM |
1613 | |
1614 | if (*len < sizeof(get)) { | |
1615 | duprintf("compat_get_entries: %u < %zu\n", *len, sizeof(get)); | |
1616 | return -EINVAL; | |
1617 | } | |
1618 | if (copy_from_user(&get, uptr, sizeof(get)) != 0) | |
1619 | return -EFAULT; | |
1620 | if (*len != sizeof(struct compat_arpt_get_entries) + get.size) { | |
1621 | duprintf("compat_get_entries: %u != %zu\n", | |
1622 | *len, sizeof(get) + get.size); | |
1623 | return -EINVAL; | |
1624 | } | |
1625 | ||
ee999d8b JE |
1626 | xt_compat_lock(NFPROTO_ARP); |
1627 | t = xt_find_table_lock(net, NFPROTO_ARP, get.name); | |
0cc8d8df | 1628 | if (!IS_ERR_OR_NULL(t)) { |
5452e425 | 1629 | const struct xt_table_info *private = t->private; |
d6a2ba07 PM |
1630 | struct xt_table_info info; |
1631 | ||
1632 | duprintf("t->private->number = %u\n", private->number); | |
1633 | ret = compat_table_info(private, &info); | |
1634 | if (!ret && get.size == info.size) { | |
1635 | ret = compat_copy_entries_to_user(private->size, | |
1636 | t, uptr->entrytable); | |
1637 | } else if (!ret) { | |
1638 | duprintf("compat_get_entries: I've got %u not %u!\n", | |
1639 | private->size, get.size); | |
544473c1 | 1640 | ret = -EAGAIN; |
d6a2ba07 | 1641 | } |
ee999d8b | 1642 | xt_compat_flush_offsets(NFPROTO_ARP); |
d6a2ba07 PM |
1643 | module_put(t->me); |
1644 | xt_table_unlock(t); | |
1645 | } else | |
1646 | ret = t ? PTR_ERR(t) : -ENOENT; | |
1647 | ||
ee999d8b | 1648 | xt_compat_unlock(NFPROTO_ARP); |
d6a2ba07 PM |
1649 | return ret; |
1650 | } | |
1651 | ||
1652 | static int do_arpt_get_ctl(struct sock *, int, void __user *, int *); | |
1653 | ||
1654 | static int compat_do_arpt_get_ctl(struct sock *sk, int cmd, void __user *user, | |
1655 | int *len) | |
1656 | { | |
1657 | int ret; | |
1658 | ||
52e804c6 | 1659 | if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) |
d6a2ba07 PM |
1660 | return -EPERM; |
1661 | ||
1662 | switch (cmd) { | |
1663 | case ARPT_SO_GET_INFO: | |
3b1e0a65 | 1664 | ret = get_info(sock_net(sk), user, len, 1); |
d6a2ba07 PM |
1665 | break; |
1666 | case ARPT_SO_GET_ENTRIES: | |
3b1e0a65 | 1667 | ret = compat_get_entries(sock_net(sk), user, len); |
d6a2ba07 PM |
1668 | break; |
1669 | default: | |
1670 | ret = do_arpt_get_ctl(sk, cmd, user, len); | |
1671 | } | |
1672 | return ret; | |
1673 | } | |
1674 | #endif | |
1675 | ||
1da177e4 LT |
1676 | static int do_arpt_set_ctl(struct sock *sk, int cmd, void __user *user, unsigned int len) |
1677 | { | |
1678 | int ret; | |
1679 | ||
52e804c6 | 1680 | if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) |
1da177e4 LT |
1681 | return -EPERM; |
1682 | ||
1683 | switch (cmd) { | |
1684 | case ARPT_SO_SET_REPLACE: | |
3b1e0a65 | 1685 | ret = do_replace(sock_net(sk), user, len); |
1da177e4 LT |
1686 | break; |
1687 | ||
1688 | case ARPT_SO_SET_ADD_COUNTERS: | |
3b1e0a65 | 1689 | ret = do_add_counters(sock_net(sk), user, len, 0); |
1da177e4 LT |
1690 | break; |
1691 | ||
1692 | default: | |
1693 | duprintf("do_arpt_set_ctl: unknown request %i\n", cmd); | |
1694 | ret = -EINVAL; | |
1695 | } | |
1696 | ||
1697 | return ret; | |
1698 | } | |
1699 | ||
1700 | static int do_arpt_get_ctl(struct sock *sk, int cmd, void __user *user, int *len) | |
1701 | { | |
1702 | int ret; | |
1703 | ||
52e804c6 | 1704 | if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) |
1da177e4 LT |
1705 | return -EPERM; |
1706 | ||
1707 | switch (cmd) { | |
41acd975 | 1708 | case ARPT_SO_GET_INFO: |
3b1e0a65 | 1709 | ret = get_info(sock_net(sk), user, len, 0); |
41acd975 | 1710 | break; |
1da177e4 | 1711 | |
11f6dff8 | 1712 | case ARPT_SO_GET_ENTRIES: |
3b1e0a65 | 1713 | ret = get_entries(sock_net(sk), user, len); |
1da177e4 | 1714 | break; |
1da177e4 | 1715 | |
6b7d31fc | 1716 | case ARPT_SO_GET_REVISION_TARGET: { |
2e4e6a17 | 1717 | struct xt_get_revision rev; |
6b7d31fc HW |
1718 | |
1719 | if (*len != sizeof(rev)) { | |
1720 | ret = -EINVAL; | |
1721 | break; | |
1722 | } | |
1723 | if (copy_from_user(&rev, user, sizeof(rev)) != 0) { | |
1724 | ret = -EFAULT; | |
1725 | break; | |
1726 | } | |
42eab94f | 1727 | rev.name[sizeof(rev.name)-1] = 0; |
6b7d31fc | 1728 | |
ee999d8b | 1729 | try_then_request_module(xt_find_revision(NFPROTO_ARP, rev.name, |
2e4e6a17 | 1730 | rev.revision, 1, &ret), |
6b7d31fc HW |
1731 | "arpt_%s", rev.name); |
1732 | break; | |
1733 | } | |
1734 | ||
1da177e4 LT |
1735 | default: |
1736 | duprintf("do_arpt_get_ctl: unknown request %i\n", cmd); | |
1737 | ret = -EINVAL; | |
1738 | } | |
1739 | ||
1740 | return ret; | |
1741 | } | |
1742 | ||
35aad0ff JE |
1743 | struct xt_table *arpt_register_table(struct net *net, |
1744 | const struct xt_table *table, | |
4abff077 | 1745 | const struct arpt_replace *repl) |
1da177e4 LT |
1746 | { |
1747 | int ret; | |
2e4e6a17 | 1748 | struct xt_table_info *newinfo; |
f3c5c1bf | 1749 | struct xt_table_info bootstrap = {0}; |
31836064 | 1750 | void *loc_cpu_entry; |
a98da11d | 1751 | struct xt_table *new_table; |
1da177e4 | 1752 | |
2e4e6a17 | 1753 | newinfo = xt_alloc_table_info(repl->size); |
1da177e4 LT |
1754 | if (!newinfo) { |
1755 | ret = -ENOMEM; | |
44d34e72 | 1756 | goto out; |
1da177e4 | 1757 | } |
31836064 ED |
1758 | |
1759 | /* choose the copy on our node/cpu */ | |
1760 | loc_cpu_entry = newinfo->entries[raw_smp_processor_id()]; | |
1761 | memcpy(loc_cpu_entry, repl->entries, repl->size); | |
1da177e4 | 1762 | |
0f234214 | 1763 | ret = translate_table(newinfo, loc_cpu_entry, repl); |
1da177e4 | 1764 | duprintf("arpt_register_table: translate table gives %d\n", ret); |
44d34e72 AD |
1765 | if (ret != 0) |
1766 | goto out_free; | |
1da177e4 | 1767 | |
79df341a | 1768 | new_table = xt_register_table(net, table, &bootstrap, newinfo); |
a98da11d | 1769 | if (IS_ERR(new_table)) { |
44d34e72 AD |
1770 | ret = PTR_ERR(new_table); |
1771 | goto out_free; | |
1da177e4 | 1772 | } |
44d34e72 | 1773 | return new_table; |
1da177e4 | 1774 | |
44d34e72 AD |
1775 | out_free: |
1776 | xt_free_table_info(newinfo); | |
1777 | out: | |
1778 | return ERR_PTR(ret); | |
1da177e4 LT |
1779 | } |
1780 | ||
4abff077 | 1781 | void arpt_unregister_table(struct xt_table *table) |
1da177e4 | 1782 | { |
2e4e6a17 | 1783 | struct xt_table_info *private; |
31836064 | 1784 | void *loc_cpu_entry; |
df200969 | 1785 | struct module *table_owner = table->me; |
72b2b1dd | 1786 | struct arpt_entry *iter; |
31836064 | 1787 | |
2e4e6a17 | 1788 | private = xt_unregister_table(table); |
1da177e4 LT |
1789 | |
1790 | /* Decrease module usage counts and free resources */ | |
2e4e6a17 | 1791 | loc_cpu_entry = private->entries[raw_smp_processor_id()]; |
72b2b1dd | 1792 | xt_entry_foreach(iter, loc_cpu_entry, private->size) |
0559518b | 1793 | cleanup_entry(iter); |
df200969 AD |
1794 | if (private->number > private->initial_entries) |
1795 | module_put(table_owner); | |
2e4e6a17 | 1796 | xt_free_table_info(private); |
1da177e4 LT |
1797 | } |
1798 | ||
1799 | /* The built-in targets: standard (NULL) and error. */ | |
4538506b JE |
1800 | static struct xt_target arpt_builtin_tg[] __read_mostly = { |
1801 | { | |
243bf6e2 | 1802 | .name = XT_STANDARD_TARGET, |
4538506b JE |
1803 | .targetsize = sizeof(int), |
1804 | .family = NFPROTO_ARP, | |
d6a2ba07 | 1805 | #ifdef CONFIG_COMPAT |
4538506b JE |
1806 | .compatsize = sizeof(compat_int_t), |
1807 | .compat_from_user = compat_standard_from_user, | |
1808 | .compat_to_user = compat_standard_to_user, | |
d6a2ba07 | 1809 | #endif |
4538506b JE |
1810 | }, |
1811 | { | |
243bf6e2 | 1812 | .name = XT_ERROR_TARGET, |
4538506b | 1813 | .target = arpt_error, |
12b00c2c | 1814 | .targetsize = XT_FUNCTION_MAXNAMELEN, |
4538506b JE |
1815 | .family = NFPROTO_ARP, |
1816 | }, | |
1da177e4 LT |
1817 | }; |
1818 | ||
1819 | static struct nf_sockopt_ops arpt_sockopts = { | |
1820 | .pf = PF_INET, | |
1821 | .set_optmin = ARPT_BASE_CTL, | |
1822 | .set_optmax = ARPT_SO_SET_MAX+1, | |
1823 | .set = do_arpt_set_ctl, | |
d6a2ba07 PM |
1824 | #ifdef CONFIG_COMPAT |
1825 | .compat_set = compat_do_arpt_set_ctl, | |
1826 | #endif | |
1da177e4 LT |
1827 | .get_optmin = ARPT_BASE_CTL, |
1828 | .get_optmax = ARPT_SO_GET_MAX+1, | |
1829 | .get = do_arpt_get_ctl, | |
d6a2ba07 PM |
1830 | #ifdef CONFIG_COMPAT |
1831 | .compat_get = compat_do_arpt_get_ctl, | |
1832 | #endif | |
16fcec35 | 1833 | .owner = THIS_MODULE, |
1da177e4 LT |
1834 | }; |
1835 | ||
3cb609d5 AD |
1836 | static int __net_init arp_tables_net_init(struct net *net) |
1837 | { | |
ee999d8b | 1838 | return xt_proto_init(net, NFPROTO_ARP); |
3cb609d5 AD |
1839 | } |
1840 | ||
1841 | static void __net_exit arp_tables_net_exit(struct net *net) | |
1842 | { | |
ee999d8b | 1843 | xt_proto_fini(net, NFPROTO_ARP); |
3cb609d5 AD |
1844 | } |
1845 | ||
1846 | static struct pernet_operations arp_tables_net_ops = { | |
1847 | .init = arp_tables_net_init, | |
1848 | .exit = arp_tables_net_exit, | |
1849 | }; | |
1850 | ||
65b4b4e8 | 1851 | static int __init arp_tables_init(void) |
1da177e4 LT |
1852 | { |
1853 | int ret; | |
1854 | ||
3cb609d5 | 1855 | ret = register_pernet_subsys(&arp_tables_net_ops); |
0eff66e6 PM |
1856 | if (ret < 0) |
1857 | goto err1; | |
2e4e6a17 | 1858 | |
25985edc | 1859 | /* No one else will be downing sem now, so we won't sleep */ |
4538506b | 1860 | ret = xt_register_targets(arpt_builtin_tg, ARRAY_SIZE(arpt_builtin_tg)); |
0eff66e6 PM |
1861 | if (ret < 0) |
1862 | goto err2; | |
1da177e4 LT |
1863 | |
1864 | /* Register setsockopt */ | |
1865 | ret = nf_register_sockopt(&arpt_sockopts); | |
0eff66e6 PM |
1866 | if (ret < 0) |
1867 | goto err4; | |
1da177e4 | 1868 | |
a887c1c1 | 1869 | printk(KERN_INFO "arp_tables: (C) 2002 David S. Miller\n"); |
1da177e4 | 1870 | return 0; |
0eff66e6 PM |
1871 | |
1872 | err4: | |
4538506b | 1873 | xt_unregister_targets(arpt_builtin_tg, ARRAY_SIZE(arpt_builtin_tg)); |
0eff66e6 | 1874 | err2: |
3cb609d5 | 1875 | unregister_pernet_subsys(&arp_tables_net_ops); |
0eff66e6 PM |
1876 | err1: |
1877 | return ret; | |
1da177e4 LT |
1878 | } |
1879 | ||
65b4b4e8 | 1880 | static void __exit arp_tables_fini(void) |
1da177e4 LT |
1881 | { |
1882 | nf_unregister_sockopt(&arpt_sockopts); | |
4538506b | 1883 | xt_unregister_targets(arpt_builtin_tg, ARRAY_SIZE(arpt_builtin_tg)); |
3cb609d5 | 1884 | unregister_pernet_subsys(&arp_tables_net_ops); |
1da177e4 LT |
1885 | } |
1886 | ||
1887 | EXPORT_SYMBOL(arpt_register_table); | |
1888 | EXPORT_SYMBOL(arpt_unregister_table); | |
1889 | EXPORT_SYMBOL(arpt_do_table); | |
1da177e4 | 1890 | |
65b4b4e8 AM |
1891 | module_init(arp_tables_init); |
1892 | module_exit(arp_tables_fini); |