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Commit | Line | Data |
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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 | 250 | unsigned int hook, |
b85c3dc9 | 251 | const struct nf_hook_state *state, |
4abff077 | 252 | struct xt_table *table) |
1da177e4 | 253 | { |
ddc214c4 | 254 | static const char nulldevname[IFNAMSIZ] __attribute__((aligned(sizeof(long)))); |
1da177e4 | 255 | unsigned int verdict = NF_DROP; |
5452e425 | 256 | const struct arphdr *arp; |
1da177e4 LT |
257 | struct arpt_entry *e, *back; |
258 | const char *indev, *outdev; | |
259 | void *table_base; | |
5452e425 | 260 | const struct xt_table_info *private; |
de74c169 | 261 | struct xt_action_param acpar; |
7f5c6d4f | 262 | unsigned int addend; |
1da177e4 | 263 | |
988b7050 | 264 | if (!pskb_may_pull(skb, arp_hdr_len(skb->dev))) |
1da177e4 LT |
265 | return NF_DROP; |
266 | ||
b85c3dc9 DM |
267 | indev = state->in ? state->in->name : nulldevname; |
268 | outdev = state->out ? state->out->name : nulldevname; | |
1da177e4 | 269 | |
7f5c6d4f ED |
270 | local_bh_disable(); |
271 | addend = xt_write_recseq_begin(); | |
942e4a2b | 272 | private = table->private; |
b416c144 WD |
273 | /* |
274 | * Ensure we load private-> members after we've fetched the base | |
275 | * pointer. | |
276 | */ | |
277 | smp_read_barrier_depends(); | |
482cfc31 | 278 | table_base = private->entries; |
78454473 | 279 | |
2e4e6a17 HW |
280 | e = get_entry(table_base, private->hook_entry[hook]); |
281 | back = get_entry(table_base, private->underflow[hook]); | |
1da177e4 | 282 | |
b85c3dc9 DM |
283 | acpar.in = state->in; |
284 | acpar.out = state->out; | |
de74c169 JE |
285 | acpar.hooknum = hook; |
286 | acpar.family = NFPROTO_ARP; | |
b4ba2611 | 287 | acpar.hotdrop = false; |
7eb35586 | 288 | |
3db05fea | 289 | arp = arp_hdr(skb); |
1da177e4 | 290 | do { |
87a2e70d | 291 | const struct xt_entry_target *t; |
71ae0dff | 292 | struct xt_counters *counter; |
a1ff4ac8 JE |
293 | |
294 | if (!arp_packet_match(arp, skb->dev, indev, outdev, &e->arp)) { | |
295 | e = arpt_next_entry(e); | |
296 | continue; | |
297 | } | |
298 | ||
71ae0dff FW |
299 | counter = xt_get_this_cpu_counter(&e->counters); |
300 | ADD_COUNTER(*counter, arp_hdr_len(skb->dev), 1); | |
1da177e4 | 301 | |
d5d1baa1 | 302 | t = arpt_get_target_c(e); |
a1ff4ac8 JE |
303 | |
304 | /* Standard target? */ | |
305 | if (!t->u.kernel.target->target) { | |
306 | int v; | |
307 | ||
87a2e70d | 308 | v = ((struct xt_standard_target *)t)->verdict; |
a1ff4ac8 JE |
309 | if (v < 0) { |
310 | /* Pop from stack? */ | |
243bf6e2 | 311 | if (v != XT_RETURN) { |
95c96174 | 312 | verdict = (unsigned int)(-v) - 1; |
1da177e4 | 313 | break; |
a1ff4ac8 JE |
314 | } |
315 | e = back; | |
316 | back = get_entry(table_base, back->comefrom); | |
317 | continue; | |
1da177e4 | 318 | } |
a1ff4ac8 JE |
319 | if (table_base + v |
320 | != arpt_next_entry(e)) { | |
321 | /* Save old back ptr in next entry */ | |
322 | struct arpt_entry *next = arpt_next_entry(e); | |
323 | next->comefrom = (void *)back - table_base; | |
324 | ||
325 | /* set back pointer to next entry */ | |
326 | back = next; | |
327 | } | |
328 | ||
329 | e = get_entry(table_base, v); | |
7a6b1c46 | 330 | continue; |
1da177e4 | 331 | } |
7a6b1c46 JE |
332 | |
333 | /* Targets which reenter must return | |
334 | * abs. verdicts | |
335 | */ | |
de74c169 JE |
336 | acpar.target = t->u.kernel.target; |
337 | acpar.targinfo = t->data; | |
338 | verdict = t->u.kernel.target->target(skb, &acpar); | |
7a6b1c46 JE |
339 | |
340 | /* Target might have changed stuff. */ | |
341 | arp = arp_hdr(skb); | |
342 | ||
243bf6e2 | 343 | if (verdict == XT_CONTINUE) |
7a6b1c46 JE |
344 | e = arpt_next_entry(e); |
345 | else | |
346 | /* Verdict */ | |
347 | break; | |
b4ba2611 | 348 | } while (!acpar.hotdrop); |
7f5c6d4f ED |
349 | xt_write_recseq_end(addend); |
350 | local_bh_enable(); | |
1da177e4 | 351 | |
b4ba2611 | 352 | if (acpar.hotdrop) |
1da177e4 LT |
353 | return NF_DROP; |
354 | else | |
355 | return verdict; | |
356 | } | |
357 | ||
1da177e4 | 358 | /* All zeroes == unconditional rule. */ |
47901dc2 | 359 | static inline bool unconditional(const struct arpt_arp *arp) |
1da177e4 | 360 | { |
47901dc2 | 361 | static const struct arpt_arp uncond; |
1da177e4 | 362 | |
47901dc2 | 363 | return memcmp(arp, &uncond, sizeof(uncond)) == 0; |
1da177e4 LT |
364 | } |
365 | ||
366 | /* Figures out from what hook each rule can be called: returns 0 if | |
367 | * there are loops. Puts hook bitmask in comefrom. | |
368 | */ | |
d5d1baa1 | 369 | static int mark_source_chains(const struct xt_table_info *newinfo, |
31836064 | 370 | unsigned int valid_hooks, void *entry0) |
1da177e4 LT |
371 | { |
372 | unsigned int hook; | |
373 | ||
374 | /* No recursion; use packet counter to save back ptrs (reset | |
375 | * to 0 as we leave), and comefrom to save source hook bitmask. | |
376 | */ | |
377 | for (hook = 0; hook < NF_ARP_NUMHOOKS; hook++) { | |
378 | unsigned int pos = newinfo->hook_entry[hook]; | |
379 | struct arpt_entry *e | |
31836064 | 380 | = (struct arpt_entry *)(entry0 + pos); |
1da177e4 LT |
381 | |
382 | if (!(valid_hooks & (1 << hook))) | |
383 | continue; | |
384 | ||
385 | /* Set initial back pointer. */ | |
386 | e->counters.pcnt = pos; | |
387 | ||
388 | for (;;) { | |
87a2e70d | 389 | const struct xt_standard_target *t |
d5d1baa1 | 390 | = (void *)arpt_get_target_c(e); |
e1b4b9f3 | 391 | int visited = e->comefrom & (1 << hook); |
1da177e4 LT |
392 | |
393 | if (e->comefrom & (1 << NF_ARP_NUMHOOKS)) { | |
654d0fbd | 394 | pr_notice("arptables: loop hook %u pos %u %08X.\n", |
1da177e4 LT |
395 | hook, pos, e->comefrom); |
396 | return 0; | |
397 | } | |
398 | e->comefrom | |
399 | |= ((1 << hook) | (1 << NF_ARP_NUMHOOKS)); | |
400 | ||
401 | /* Unconditional return/END. */ | |
3666ed1c JP |
402 | if ((e->target_offset == sizeof(struct arpt_entry) && |
403 | (strcmp(t->target.u.user.name, | |
243bf6e2 | 404 | XT_STANDARD_TARGET) == 0) && |
3666ed1c JP |
405 | t->verdict < 0 && unconditional(&e->arp)) || |
406 | visited) { | |
1da177e4 LT |
407 | unsigned int oldpos, size; |
408 | ||
1f9352ae | 409 | if ((strcmp(t->target.u.user.name, |
243bf6e2 | 410 | XT_STANDARD_TARGET) == 0) && |
1f9352ae | 411 | t->verdict < -NF_MAX_VERDICT - 1) { |
74c9c0c1 DM |
412 | duprintf("mark_source_chains: bad " |
413 | "negative verdict (%i)\n", | |
414 | t->verdict); | |
415 | return 0; | |
416 | } | |
417 | ||
1da177e4 LT |
418 | /* Return: backtrack through the last |
419 | * big jump. | |
420 | */ | |
421 | do { | |
422 | e->comefrom ^= (1<<NF_ARP_NUMHOOKS); | |
423 | oldpos = pos; | |
424 | pos = e->counters.pcnt; | |
425 | e->counters.pcnt = 0; | |
426 | ||
427 | /* We're at the start. */ | |
428 | if (pos == oldpos) | |
429 | goto next; | |
430 | ||
431 | e = (struct arpt_entry *) | |
31836064 | 432 | (entry0 + pos); |
1da177e4 LT |
433 | } while (oldpos == pos + e->next_offset); |
434 | ||
435 | /* Move along one */ | |
436 | size = e->next_offset; | |
437 | e = (struct arpt_entry *) | |
31836064 | 438 | (entry0 + pos + size); |
1da177e4 LT |
439 | e->counters.pcnt = pos; |
440 | pos += size; | |
441 | } else { | |
442 | int newpos = t->verdict; | |
443 | ||
444 | if (strcmp(t->target.u.user.name, | |
243bf6e2 | 445 | XT_STANDARD_TARGET) == 0 && |
3666ed1c | 446 | newpos >= 0) { |
74c9c0c1 DM |
447 | if (newpos > newinfo->size - |
448 | sizeof(struct arpt_entry)) { | |
449 | duprintf("mark_source_chains: " | |
450 | "bad verdict (%i)\n", | |
451 | newpos); | |
452 | return 0; | |
453 | } | |
454 | ||
1da177e4 LT |
455 | /* This a jump; chase it. */ |
456 | duprintf("Jump rule %u -> %u\n", | |
457 | pos, newpos); | |
458 | } else { | |
459 | /* ... this is a fallthru */ | |
460 | newpos = pos + e->next_offset; | |
461 | } | |
462 | e = (struct arpt_entry *) | |
31836064 | 463 | (entry0 + newpos); |
1da177e4 LT |
464 | e->counters.pcnt = pos; |
465 | pos = newpos; | |
466 | } | |
467 | } | |
468 | next: | |
469 | duprintf("Finished chain %u\n", hook); | |
470 | } | |
471 | return 1; | |
472 | } | |
473 | ||
d5d1baa1 | 474 | static inline int check_entry(const struct arpt_entry *e, const char *name) |
1da177e4 | 475 | { |
87a2e70d | 476 | const struct xt_entry_target *t; |
1da177e4 LT |
477 | |
478 | if (!arp_checkentry(&e->arp)) { | |
479 | duprintf("arp_tables: arp check failed %p %s.\n", e, name); | |
480 | return -EINVAL; | |
481 | } | |
482 | ||
87a2e70d | 483 | if (e->target_offset + sizeof(struct xt_entry_target) > e->next_offset) |
590bdf7f DM |
484 | return -EINVAL; |
485 | ||
d5d1baa1 | 486 | t = arpt_get_target_c(e); |
590bdf7f DM |
487 | if (e->target_offset + t->u.target_size > e->next_offset) |
488 | return -EINVAL; | |
489 | ||
fb5b6095 PM |
490 | return 0; |
491 | } | |
492 | ||
493 | static inline int check_target(struct arpt_entry *e, const char *name) | |
494 | { | |
87a2e70d | 495 | struct xt_entry_target *t = arpt_get_target(e); |
fb5b6095 | 496 | int ret; |
af5d6dc2 JE |
497 | struct xt_tgchk_param par = { |
498 | .table = name, | |
499 | .entryinfo = e, | |
500 | .target = t->u.kernel.target, | |
501 | .targinfo = t->data, | |
502 | .hook_mask = e->comefrom, | |
916a917d | 503 | .family = NFPROTO_ARP, |
af5d6dc2 JE |
504 | }; |
505 | ||
916a917d | 506 | ret = xt_check_target(&par, t->u.target_size - sizeof(*t), 0, false); |
367c6790 | 507 | if (ret < 0) { |
fb5b6095 PM |
508 | duprintf("arp_tables: check failed for `%s'.\n", |
509 | t->u.kernel.target->name); | |
367c6790 | 510 | return ret; |
fb5b6095 | 511 | } |
367c6790 | 512 | return 0; |
fb5b6095 PM |
513 | } |
514 | ||
515 | static inline int | |
0559518b | 516 | find_check_entry(struct arpt_entry *e, const char *name, unsigned int size) |
fb5b6095 | 517 | { |
87a2e70d | 518 | struct xt_entry_target *t; |
95eea855 | 519 | struct xt_target *target; |
fb5b6095 PM |
520 | int ret; |
521 | ||
522 | ret = check_entry(e, name); | |
523 | if (ret) | |
524 | return ret; | |
525 | ||
71ae0dff FW |
526 | e->counters.pcnt = xt_percpu_counter_alloc(); |
527 | if (IS_ERR_VALUE(e->counters.pcnt)) | |
528 | return -ENOMEM; | |
529 | ||
fb5b6095 | 530 | t = arpt_get_target(e); |
d2a7b6ba JE |
531 | target = xt_request_find_target(NFPROTO_ARP, t->u.user.name, |
532 | t->u.user.revision); | |
533 | if (IS_ERR(target)) { | |
fb5b6095 | 534 | duprintf("find_check_entry: `%s' not found\n", t->u.user.name); |
d2a7b6ba | 535 | ret = PTR_ERR(target); |
1da177e4 LT |
536 | goto out; |
537 | } | |
1da177e4 | 538 | t->u.kernel.target = target; |
1da177e4 | 539 | |
fb5b6095 | 540 | ret = check_target(e, name); |
3cdc7c95 PM |
541 | if (ret) |
542 | goto err; | |
1da177e4 | 543 | return 0; |
3cdc7c95 PM |
544 | err: |
545 | module_put(t->u.kernel.target->me); | |
1da177e4 | 546 | out: |
71ae0dff FW |
547 | xt_percpu_counter_free(e->counters.pcnt); |
548 | ||
1da177e4 LT |
549 | return ret; |
550 | } | |
551 | ||
d5d1baa1 | 552 | static bool check_underflow(const struct arpt_entry *e) |
e2fe35c1 | 553 | { |
87a2e70d | 554 | const struct xt_entry_target *t; |
e2fe35c1 JE |
555 | unsigned int verdict; |
556 | ||
557 | if (!unconditional(&e->arp)) | |
558 | return false; | |
d5d1baa1 | 559 | t = arpt_get_target_c(e); |
e2fe35c1 JE |
560 | if (strcmp(t->u.user.name, XT_STANDARD_TARGET) != 0) |
561 | return false; | |
87a2e70d | 562 | verdict = ((struct xt_standard_target *)t)->verdict; |
e2fe35c1 JE |
563 | verdict = -verdict - 1; |
564 | return verdict == NF_DROP || verdict == NF_ACCEPT; | |
565 | } | |
566 | ||
1da177e4 | 567 | static inline int check_entry_size_and_hooks(struct arpt_entry *e, |
2e4e6a17 | 568 | struct xt_table_info *newinfo, |
d5d1baa1 JE |
569 | const unsigned char *base, |
570 | const unsigned char *limit, | |
1da177e4 LT |
571 | const unsigned int *hook_entries, |
572 | const unsigned int *underflows, | |
0559518b | 573 | unsigned int valid_hooks) |
1da177e4 LT |
574 | { |
575 | unsigned int h; | |
576 | ||
3666ed1c JP |
577 | if ((unsigned long)e % __alignof__(struct arpt_entry) != 0 || |
578 | (unsigned char *)e + sizeof(struct arpt_entry) >= limit) { | |
1da177e4 LT |
579 | duprintf("Bad offset %p\n", e); |
580 | return -EINVAL; | |
581 | } | |
582 | ||
583 | if (e->next_offset | |
87a2e70d | 584 | < sizeof(struct arpt_entry) + sizeof(struct xt_entry_target)) { |
1da177e4 LT |
585 | duprintf("checking: element %p size %u\n", |
586 | e, e->next_offset); | |
587 | return -EINVAL; | |
588 | } | |
589 | ||
590 | /* Check hooks & underflows */ | |
591 | for (h = 0; h < NF_ARP_NUMHOOKS; h++) { | |
a7d51738 JE |
592 | if (!(valid_hooks & (1 << h))) |
593 | continue; | |
1da177e4 LT |
594 | if ((unsigned char *)e - base == hook_entries[h]) |
595 | newinfo->hook_entry[h] = hook_entries[h]; | |
90e7d4ab | 596 | if ((unsigned char *)e - base == underflows[h]) { |
e2fe35c1 JE |
597 | if (!check_underflow(e)) { |
598 | pr_err("Underflows must be unconditional and " | |
599 | "use the STANDARD target with " | |
600 | "ACCEPT/DROP\n"); | |
90e7d4ab JE |
601 | return -EINVAL; |
602 | } | |
1da177e4 | 603 | newinfo->underflow[h] = underflows[h]; |
90e7d4ab | 604 | } |
1da177e4 LT |
605 | } |
606 | ||
1da177e4 | 607 | /* Clear counters and comefrom */ |
2e4e6a17 | 608 | e->counters = ((struct xt_counters) { 0, 0 }); |
1da177e4 | 609 | e->comefrom = 0; |
1da177e4 LT |
610 | return 0; |
611 | } | |
612 | ||
0559518b | 613 | static inline void cleanup_entry(struct arpt_entry *e) |
1da177e4 | 614 | { |
a2df1648 | 615 | struct xt_tgdtor_param par; |
87a2e70d | 616 | struct xt_entry_target *t; |
1da177e4 | 617 | |
1da177e4 | 618 | t = arpt_get_target(e); |
a2df1648 JE |
619 | par.target = t->u.kernel.target; |
620 | par.targinfo = t->data; | |
916a917d | 621 | par.family = NFPROTO_ARP; |
a2df1648 JE |
622 | if (par.target->destroy != NULL) |
623 | par.target->destroy(&par); | |
624 | module_put(par.target->me); | |
71ae0dff | 625 | xt_percpu_counter_free(e->counters.pcnt); |
1da177e4 LT |
626 | } |
627 | ||
628 | /* Checks and translates the user-supplied table segment (held in | |
629 | * newinfo). | |
630 | */ | |
0f234214 JE |
631 | static int translate_table(struct xt_table_info *newinfo, void *entry0, |
632 | const struct arpt_replace *repl) | |
1da177e4 | 633 | { |
72b2b1dd | 634 | struct arpt_entry *iter; |
1da177e4 | 635 | unsigned int i; |
72b2b1dd | 636 | int ret = 0; |
1da177e4 | 637 | |
0f234214 JE |
638 | newinfo->size = repl->size; |
639 | newinfo->number = repl->num_entries; | |
1da177e4 LT |
640 | |
641 | /* Init all hooks to impossible value. */ | |
642 | for (i = 0; i < NF_ARP_NUMHOOKS; i++) { | |
643 | newinfo->hook_entry[i] = 0xFFFFFFFF; | |
644 | newinfo->underflow[i] = 0xFFFFFFFF; | |
645 | } | |
646 | ||
647 | duprintf("translate_table: size %u\n", newinfo->size); | |
648 | i = 0; | |
649 | ||
650 | /* Walk through entries, checking offsets. */ | |
72b2b1dd JE |
651 | xt_entry_foreach(iter, entry0, newinfo->size) { |
652 | ret = check_entry_size_and_hooks(iter, newinfo, entry0, | |
6b4ff2d7 JE |
653 | entry0 + repl->size, |
654 | repl->hook_entry, | |
655 | repl->underflow, | |
656 | repl->valid_hooks); | |
72b2b1dd JE |
657 | if (ret != 0) |
658 | break; | |
0559518b | 659 | ++i; |
f3c5c1bf JE |
660 | if (strcmp(arpt_get_target(iter)->u.user.name, |
661 | XT_ERROR_TARGET) == 0) | |
662 | ++newinfo->stacksize; | |
72b2b1dd | 663 | } |
1da177e4 LT |
664 | duprintf("translate_table: ARPT_ENTRY_ITERATE gives %d\n", ret); |
665 | if (ret != 0) | |
666 | return ret; | |
667 | ||
0f234214 | 668 | if (i != repl->num_entries) { |
1da177e4 | 669 | duprintf("translate_table: %u not %u entries\n", |
0f234214 | 670 | i, repl->num_entries); |
1da177e4 LT |
671 | return -EINVAL; |
672 | } | |
673 | ||
674 | /* Check hooks all assigned */ | |
675 | for (i = 0; i < NF_ARP_NUMHOOKS; i++) { | |
676 | /* Only hooks which are valid */ | |
0f234214 | 677 | if (!(repl->valid_hooks & (1 << i))) |
1da177e4 LT |
678 | continue; |
679 | if (newinfo->hook_entry[i] == 0xFFFFFFFF) { | |
680 | duprintf("Invalid hook entry %u %u\n", | |
0f234214 | 681 | i, repl->hook_entry[i]); |
1da177e4 LT |
682 | return -EINVAL; |
683 | } | |
684 | if (newinfo->underflow[i] == 0xFFFFFFFF) { | |
685 | duprintf("Invalid underflow %u %u\n", | |
0f234214 | 686 | i, repl->underflow[i]); |
1da177e4 LT |
687 | return -EINVAL; |
688 | } | |
689 | } | |
690 | ||
0f234214 | 691 | if (!mark_source_chains(newinfo, repl->valid_hooks, entry0)) { |
74c9c0c1 DM |
692 | duprintf("Looping hook\n"); |
693 | return -ELOOP; | |
694 | } | |
695 | ||
1da177e4 LT |
696 | /* Finally, each sanity check must pass */ |
697 | i = 0; | |
72b2b1dd | 698 | xt_entry_foreach(iter, entry0, newinfo->size) { |
0f234214 | 699 | ret = find_check_entry(iter, repl->name, repl->size); |
72b2b1dd JE |
700 | if (ret != 0) |
701 | break; | |
0559518b | 702 | ++i; |
72b2b1dd | 703 | } |
1da177e4 | 704 | |
74c9c0c1 | 705 | if (ret != 0) { |
0559518b JE |
706 | xt_entry_foreach(iter, entry0, newinfo->size) { |
707 | if (i-- == 0) | |
72b2b1dd | 708 | break; |
0559518b JE |
709 | cleanup_entry(iter); |
710 | } | |
74c9c0c1 | 711 | return ret; |
1da177e4 LT |
712 | } |
713 | ||
1da177e4 LT |
714 | return ret; |
715 | } | |
716 | ||
2e4e6a17 HW |
717 | static void get_counters(const struct xt_table_info *t, |
718 | struct xt_counters counters[]) | |
1da177e4 | 719 | { |
72b2b1dd | 720 | struct arpt_entry *iter; |
1da177e4 LT |
721 | unsigned int cpu; |
722 | unsigned int i; | |
723 | ||
6f912042 | 724 | for_each_possible_cpu(cpu) { |
7f5c6d4f | 725 | seqcount_t *s = &per_cpu(xt_recseq, cpu); |
83723d60 | 726 | |
1da177e4 | 727 | i = 0; |
482cfc31 | 728 | xt_entry_foreach(iter, t->entries, t->size) { |
71ae0dff | 729 | struct xt_counters *tmp; |
83723d60 ED |
730 | u64 bcnt, pcnt; |
731 | unsigned int start; | |
732 | ||
71ae0dff | 733 | tmp = xt_get_per_cpu_counter(&iter->counters, cpu); |
83723d60 | 734 | do { |
7f5c6d4f | 735 | start = read_seqcount_begin(s); |
71ae0dff FW |
736 | bcnt = tmp->bcnt; |
737 | pcnt = tmp->pcnt; | |
7f5c6d4f | 738 | } while (read_seqcount_retry(s, start)); |
83723d60 ED |
739 | |
740 | ADD_COUNTER(counters[i], bcnt, pcnt); | |
0559518b JE |
741 | ++i; |
742 | } | |
1da177e4 | 743 | } |
78454473 SH |
744 | } |
745 | ||
d5d1baa1 | 746 | static struct xt_counters *alloc_counters(const struct xt_table *table) |
1da177e4 | 747 | { |
27e2c26b | 748 | unsigned int countersize; |
2e4e6a17 | 749 | struct xt_counters *counters; |
d5d1baa1 | 750 | const struct xt_table_info *private = table->private; |
1da177e4 LT |
751 | |
752 | /* We need atomic snapshot of counters: rest doesn't change | |
753 | * (other than comefrom, which userspace doesn't care | |
754 | * about). | |
755 | */ | |
2e4e6a17 | 756 | countersize = sizeof(struct xt_counters) * private->number; |
83723d60 | 757 | counters = vzalloc(countersize); |
1da177e4 LT |
758 | |
759 | if (counters == NULL) | |
942e4a2b | 760 | return ERR_PTR(-ENOMEM); |
78454473 | 761 | |
942e4a2b | 762 | get_counters(private, counters); |
1da177e4 | 763 | |
27e2c26b PM |
764 | return counters; |
765 | } | |
766 | ||
767 | static int copy_entries_to_user(unsigned int total_size, | |
d5d1baa1 | 768 | const struct xt_table *table, |
27e2c26b PM |
769 | void __user *userptr) |
770 | { | |
771 | unsigned int off, num; | |
d5d1baa1 | 772 | const struct arpt_entry *e; |
27e2c26b | 773 | struct xt_counters *counters; |
4abff077 | 774 | struct xt_table_info *private = table->private; |
27e2c26b PM |
775 | int ret = 0; |
776 | void *loc_cpu_entry; | |
777 | ||
778 | counters = alloc_counters(table); | |
779 | if (IS_ERR(counters)) | |
780 | return PTR_ERR(counters); | |
781 | ||
482cfc31 | 782 | loc_cpu_entry = private->entries; |
31836064 ED |
783 | /* ... then copy entire thing ... */ |
784 | if (copy_to_user(userptr, loc_cpu_entry, total_size) != 0) { | |
1da177e4 LT |
785 | ret = -EFAULT; |
786 | goto free_counters; | |
787 | } | |
788 | ||
789 | /* FIXME: use iterator macros --RR */ | |
790 | /* ... then go back and fix counters and names */ | |
791 | for (off = 0, num = 0; off < total_size; off += e->next_offset, num++){ | |
87a2e70d | 792 | const struct xt_entry_target *t; |
1da177e4 | 793 | |
31836064 | 794 | e = (struct arpt_entry *)(loc_cpu_entry + off); |
1da177e4 LT |
795 | if (copy_to_user(userptr + off |
796 | + offsetof(struct arpt_entry, counters), | |
797 | &counters[num], | |
798 | sizeof(counters[num])) != 0) { | |
799 | ret = -EFAULT; | |
800 | goto free_counters; | |
801 | } | |
802 | ||
d5d1baa1 | 803 | t = arpt_get_target_c(e); |
1da177e4 | 804 | if (copy_to_user(userptr + off + e->target_offset |
87a2e70d | 805 | + offsetof(struct xt_entry_target, |
1da177e4 LT |
806 | u.user.name), |
807 | t->u.kernel.target->name, | |
808 | strlen(t->u.kernel.target->name)+1) != 0) { | |
809 | ret = -EFAULT; | |
810 | goto free_counters; | |
811 | } | |
812 | } | |
813 | ||
814 | free_counters: | |
815 | vfree(counters); | |
816 | return ret; | |
817 | } | |
818 | ||
d6a2ba07 | 819 | #ifdef CONFIG_COMPAT |
739674fb | 820 | static void compat_standard_from_user(void *dst, const void *src) |
d6a2ba07 PM |
821 | { |
822 | int v = *(compat_int_t *)src; | |
823 | ||
824 | if (v > 0) | |
ee999d8b | 825 | v += xt_compat_calc_jump(NFPROTO_ARP, v); |
d6a2ba07 PM |
826 | memcpy(dst, &v, sizeof(v)); |
827 | } | |
828 | ||
739674fb | 829 | static int compat_standard_to_user(void __user *dst, const void *src) |
d6a2ba07 PM |
830 | { |
831 | compat_int_t cv = *(int *)src; | |
832 | ||
833 | if (cv > 0) | |
ee999d8b | 834 | cv -= xt_compat_calc_jump(NFPROTO_ARP, cv); |
d6a2ba07 PM |
835 | return copy_to_user(dst, &cv, sizeof(cv)) ? -EFAULT : 0; |
836 | } | |
837 | ||
d5d1baa1 | 838 | static int compat_calc_entry(const struct arpt_entry *e, |
d6a2ba07 | 839 | const struct xt_table_info *info, |
d5d1baa1 | 840 | const void *base, struct xt_table_info *newinfo) |
d6a2ba07 | 841 | { |
87a2e70d | 842 | const struct xt_entry_target *t; |
d6a2ba07 PM |
843 | unsigned int entry_offset; |
844 | int off, i, ret; | |
845 | ||
846 | off = sizeof(struct arpt_entry) - sizeof(struct compat_arpt_entry); | |
847 | entry_offset = (void *)e - base; | |
848 | ||
d5d1baa1 | 849 | t = arpt_get_target_c(e); |
d6a2ba07 PM |
850 | off += xt_compat_target_offset(t->u.kernel.target); |
851 | newinfo->size -= off; | |
ee999d8b | 852 | ret = xt_compat_add_offset(NFPROTO_ARP, entry_offset, off); |
d6a2ba07 PM |
853 | if (ret) |
854 | return ret; | |
855 | ||
856 | for (i = 0; i < NF_ARP_NUMHOOKS; i++) { | |
857 | if (info->hook_entry[i] && | |
858 | (e < (struct arpt_entry *)(base + info->hook_entry[i]))) | |
859 | newinfo->hook_entry[i] -= off; | |
860 | if (info->underflow[i] && | |
861 | (e < (struct arpt_entry *)(base + info->underflow[i]))) | |
862 | newinfo->underflow[i] -= off; | |
863 | } | |
864 | return 0; | |
865 | } | |
866 | ||
867 | static int compat_table_info(const struct xt_table_info *info, | |
868 | struct xt_table_info *newinfo) | |
869 | { | |
72b2b1dd | 870 | struct arpt_entry *iter; |
d6a2ba07 | 871 | void *loc_cpu_entry; |
0559518b | 872 | int ret; |
d6a2ba07 PM |
873 | |
874 | if (!newinfo || !info) | |
875 | return -EINVAL; | |
876 | ||
482cfc31 | 877 | /* we dont care about newinfo->entries */ |
d6a2ba07 PM |
878 | memcpy(newinfo, info, offsetof(struct xt_table_info, entries)); |
879 | newinfo->initial_entries = 0; | |
482cfc31 | 880 | loc_cpu_entry = info->entries; |
255d0dc3 | 881 | xt_compat_init_offsets(NFPROTO_ARP, info->number); |
72b2b1dd JE |
882 | xt_entry_foreach(iter, loc_cpu_entry, info->size) { |
883 | ret = compat_calc_entry(iter, info, loc_cpu_entry, newinfo); | |
884 | if (ret != 0) | |
0559518b | 885 | return ret; |
72b2b1dd | 886 | } |
0559518b | 887 | return 0; |
d6a2ba07 PM |
888 | } |
889 | #endif | |
890 | ||
d5d1baa1 JE |
891 | static int get_info(struct net *net, void __user *user, |
892 | const int *len, int compat) | |
41acd975 | 893 | { |
12b00c2c | 894 | char name[XT_TABLE_MAXNAMELEN]; |
4abff077 | 895 | struct xt_table *t; |
41acd975 PM |
896 | int ret; |
897 | ||
898 | if (*len != sizeof(struct arpt_getinfo)) { | |
899 | duprintf("length %u != %Zu\n", *len, | |
900 | sizeof(struct arpt_getinfo)); | |
901 | return -EINVAL; | |
902 | } | |
903 | ||
904 | if (copy_from_user(name, user, sizeof(name)) != 0) | |
905 | return -EFAULT; | |
906 | ||
12b00c2c | 907 | name[XT_TABLE_MAXNAMELEN-1] = '\0'; |
d6a2ba07 PM |
908 | #ifdef CONFIG_COMPAT |
909 | if (compat) | |
ee999d8b | 910 | xt_compat_lock(NFPROTO_ARP); |
d6a2ba07 | 911 | #endif |
ee999d8b | 912 | t = try_then_request_module(xt_find_table_lock(net, NFPROTO_ARP, name), |
41acd975 | 913 | "arptable_%s", name); |
0cc8d8df | 914 | if (!IS_ERR_OR_NULL(t)) { |
41acd975 | 915 | struct arpt_getinfo info; |
5452e425 | 916 | const struct xt_table_info *private = t->private; |
d6a2ba07 | 917 | #ifdef CONFIG_COMPAT |
14c7dbe0 AD |
918 | struct xt_table_info tmp; |
919 | ||
d6a2ba07 | 920 | if (compat) { |
d6a2ba07 | 921 | ret = compat_table_info(private, &tmp); |
ee999d8b | 922 | xt_compat_flush_offsets(NFPROTO_ARP); |
d6a2ba07 PM |
923 | private = &tmp; |
924 | } | |
925 | #endif | |
1a8b7a67 | 926 | memset(&info, 0, sizeof(info)); |
41acd975 PM |
927 | info.valid_hooks = t->valid_hooks; |
928 | memcpy(info.hook_entry, private->hook_entry, | |
929 | sizeof(info.hook_entry)); | |
930 | memcpy(info.underflow, private->underflow, | |
931 | sizeof(info.underflow)); | |
932 | info.num_entries = private->number; | |
933 | info.size = private->size; | |
934 | strcpy(info.name, name); | |
935 | ||
936 | if (copy_to_user(user, &info, *len) != 0) | |
937 | ret = -EFAULT; | |
938 | else | |
939 | ret = 0; | |
940 | xt_table_unlock(t); | |
941 | module_put(t->me); | |
942 | } else | |
943 | ret = t ? PTR_ERR(t) : -ENOENT; | |
d6a2ba07 PM |
944 | #ifdef CONFIG_COMPAT |
945 | if (compat) | |
ee999d8b | 946 | xt_compat_unlock(NFPROTO_ARP); |
d6a2ba07 | 947 | #endif |
41acd975 PM |
948 | return ret; |
949 | } | |
950 | ||
79df341a | 951 | static int get_entries(struct net *net, struct arpt_get_entries __user *uptr, |
d5d1baa1 | 952 | const int *len) |
1da177e4 LT |
953 | { |
954 | int ret; | |
11f6dff8 | 955 | struct arpt_get_entries get; |
4abff077 | 956 | struct xt_table *t; |
1da177e4 | 957 | |
11f6dff8 PM |
958 | if (*len < sizeof(get)) { |
959 | duprintf("get_entries: %u < %Zu\n", *len, sizeof(get)); | |
960 | return -EINVAL; | |
961 | } | |
962 | if (copy_from_user(&get, uptr, sizeof(get)) != 0) | |
963 | return -EFAULT; | |
964 | if (*len != sizeof(struct arpt_get_entries) + get.size) { | |
965 | duprintf("get_entries: %u != %Zu\n", *len, | |
966 | sizeof(struct arpt_get_entries) + get.size); | |
967 | return -EINVAL; | |
968 | } | |
969 | ||
ee999d8b | 970 | t = xt_find_table_lock(net, NFPROTO_ARP, get.name); |
0cc8d8df | 971 | if (!IS_ERR_OR_NULL(t)) { |
5452e425 JE |
972 | const struct xt_table_info *private = t->private; |
973 | ||
1da177e4 | 974 | duprintf("t->private->number = %u\n", |
2e4e6a17 | 975 | private->number); |
11f6dff8 | 976 | if (get.size == private->size) |
2e4e6a17 | 977 | ret = copy_entries_to_user(private->size, |
1da177e4 LT |
978 | t, uptr->entrytable); |
979 | else { | |
980 | duprintf("get_entries: I've got %u not %u!\n", | |
11f6dff8 | 981 | private->size, get.size); |
544473c1 | 982 | ret = -EAGAIN; |
1da177e4 | 983 | } |
6b7d31fc | 984 | module_put(t->me); |
2e4e6a17 | 985 | xt_table_unlock(t); |
1da177e4 | 986 | } else |
6b7d31fc | 987 | ret = t ? PTR_ERR(t) : -ENOENT; |
1da177e4 LT |
988 | |
989 | return ret; | |
990 | } | |
991 | ||
79df341a AD |
992 | static int __do_replace(struct net *net, const char *name, |
993 | unsigned int valid_hooks, | |
d6a2ba07 PM |
994 | struct xt_table_info *newinfo, |
995 | unsigned int num_counters, | |
996 | void __user *counters_ptr) | |
1da177e4 LT |
997 | { |
998 | int ret; | |
4abff077 | 999 | struct xt_table *t; |
d6a2ba07 | 1000 | struct xt_table_info *oldinfo; |
2e4e6a17 | 1001 | struct xt_counters *counters; |
d6a2ba07 | 1002 | void *loc_cpu_old_entry; |
72b2b1dd | 1003 | struct arpt_entry *iter; |
1da177e4 | 1004 | |
d6a2ba07 | 1005 | ret = 0; |
83723d60 | 1006 | counters = vzalloc(num_counters * sizeof(struct xt_counters)); |
1da177e4 LT |
1007 | if (!counters) { |
1008 | ret = -ENOMEM; | |
d6a2ba07 | 1009 | goto out; |
1da177e4 | 1010 | } |
1da177e4 | 1011 | |
ee999d8b | 1012 | t = try_then_request_module(xt_find_table_lock(net, NFPROTO_ARP, name), |
d6a2ba07 | 1013 | "arptable_%s", name); |
0cc8d8df | 1014 | if (IS_ERR_OR_NULL(t)) { |
6b7d31fc | 1015 | ret = t ? PTR_ERR(t) : -ENOENT; |
1da177e4 | 1016 | goto free_newinfo_counters_untrans; |
6b7d31fc | 1017 | } |
1da177e4 LT |
1018 | |
1019 | /* You lied! */ | |
d6a2ba07 | 1020 | if (valid_hooks != t->valid_hooks) { |
1da177e4 | 1021 | duprintf("Valid hook crap: %08X vs %08X\n", |
d6a2ba07 | 1022 | valid_hooks, t->valid_hooks); |
1da177e4 | 1023 | ret = -EINVAL; |
6b7d31fc | 1024 | goto put_module; |
1da177e4 LT |
1025 | } |
1026 | ||
d6a2ba07 | 1027 | oldinfo = xt_replace_table(t, num_counters, newinfo, &ret); |
1da177e4 LT |
1028 | if (!oldinfo) |
1029 | goto put_module; | |
1030 | ||
1031 | /* Update module usage count based on number of rules */ | |
1032 | duprintf("do_replace: oldnum=%u, initnum=%u, newnum=%u\n", | |
1033 | oldinfo->number, oldinfo->initial_entries, newinfo->number); | |
e905a9ed YH |
1034 | if ((oldinfo->number > oldinfo->initial_entries) || |
1035 | (newinfo->number <= oldinfo->initial_entries)) | |
1da177e4 LT |
1036 | module_put(t->me); |
1037 | if ((oldinfo->number > oldinfo->initial_entries) && | |
1038 | (newinfo->number <= oldinfo->initial_entries)) | |
1039 | module_put(t->me); | |
1040 | ||
942e4a2b | 1041 | /* Get the old counters, and synchronize with replace */ |
1da177e4 | 1042 | get_counters(oldinfo, counters); |
942e4a2b | 1043 | |
1da177e4 | 1044 | /* Decrease module usage counts and free resource */ |
482cfc31 | 1045 | loc_cpu_old_entry = oldinfo->entries; |
72b2b1dd | 1046 | xt_entry_foreach(iter, loc_cpu_old_entry, oldinfo->size) |
0559518b | 1047 | cleanup_entry(iter); |
31836064 | 1048 | |
2e4e6a17 | 1049 | xt_free_table_info(oldinfo); |
d6a2ba07 | 1050 | if (copy_to_user(counters_ptr, counters, |
c58dd2dd TG |
1051 | sizeof(struct xt_counters) * num_counters) != 0) { |
1052 | /* Silent error, can't fail, new table is already in place */ | |
1053 | net_warn_ratelimited("arptables: counters copy to user failed while replacing table\n"); | |
1054 | } | |
1da177e4 | 1055 | vfree(counters); |
2e4e6a17 | 1056 | xt_table_unlock(t); |
1da177e4 LT |
1057 | return ret; |
1058 | ||
1059 | put_module: | |
1060 | module_put(t->me); | |
2e4e6a17 | 1061 | xt_table_unlock(t); |
1da177e4 | 1062 | free_newinfo_counters_untrans: |
1da177e4 | 1063 | vfree(counters); |
d6a2ba07 PM |
1064 | out: |
1065 | return ret; | |
1066 | } | |
1067 | ||
d5d1baa1 JE |
1068 | static int do_replace(struct net *net, const void __user *user, |
1069 | unsigned int len) | |
d6a2ba07 PM |
1070 | { |
1071 | int ret; | |
1072 | struct arpt_replace tmp; | |
1073 | struct xt_table_info *newinfo; | |
1074 | void *loc_cpu_entry; | |
72b2b1dd | 1075 | struct arpt_entry *iter; |
d6a2ba07 PM |
1076 | |
1077 | if (copy_from_user(&tmp, user, sizeof(tmp)) != 0) | |
1078 | return -EFAULT; | |
1079 | ||
1080 | /* overflow check */ | |
1081 | if (tmp.num_counters >= INT_MAX / sizeof(struct xt_counters)) | |
1082 | return -ENOMEM; | |
1086bbe9 DJ |
1083 | if (tmp.num_counters == 0) |
1084 | return -EINVAL; | |
1085 | ||
42eab94f | 1086 | tmp.name[sizeof(tmp.name)-1] = 0; |
d6a2ba07 PM |
1087 | |
1088 | newinfo = xt_alloc_table_info(tmp.size); | |
1089 | if (!newinfo) | |
1090 | return -ENOMEM; | |
1091 | ||
482cfc31 | 1092 | loc_cpu_entry = newinfo->entries; |
d6a2ba07 PM |
1093 | if (copy_from_user(loc_cpu_entry, user + sizeof(tmp), |
1094 | tmp.size) != 0) { | |
1095 | ret = -EFAULT; | |
1096 | goto free_newinfo; | |
1097 | } | |
1098 | ||
0f234214 | 1099 | ret = translate_table(newinfo, loc_cpu_entry, &tmp); |
d6a2ba07 PM |
1100 | if (ret != 0) |
1101 | goto free_newinfo; | |
1102 | ||
1103 | duprintf("arp_tables: Translated table\n"); | |
1104 | ||
79df341a | 1105 | ret = __do_replace(net, tmp.name, tmp.valid_hooks, newinfo, |
d6a2ba07 PM |
1106 | tmp.num_counters, tmp.counters); |
1107 | if (ret) | |
1108 | goto free_newinfo_untrans; | |
1109 | return 0; | |
1110 | ||
1111 | free_newinfo_untrans: | |
72b2b1dd | 1112 | xt_entry_foreach(iter, loc_cpu_entry, newinfo->size) |
0559518b | 1113 | cleanup_entry(iter); |
1da177e4 | 1114 | free_newinfo: |
2e4e6a17 | 1115 | xt_free_table_info(newinfo); |
1da177e4 LT |
1116 | return ret; |
1117 | } | |
1118 | ||
d5d1baa1 JE |
1119 | static int do_add_counters(struct net *net, const void __user *user, |
1120 | unsigned int len, int compat) | |
1da177e4 | 1121 | { |
482cfc31 | 1122 | unsigned int i; |
d6a2ba07 PM |
1123 | struct xt_counters_info tmp; |
1124 | struct xt_counters *paddc; | |
1125 | unsigned int num_counters; | |
5452e425 | 1126 | const char *name; |
d6a2ba07 PM |
1127 | int size; |
1128 | void *ptmp; | |
4abff077 | 1129 | struct xt_table *t; |
5452e425 | 1130 | const struct xt_table_info *private; |
6b7d31fc | 1131 | int ret = 0; |
72b2b1dd | 1132 | struct arpt_entry *iter; |
7f5c6d4f | 1133 | unsigned int addend; |
d6a2ba07 PM |
1134 | #ifdef CONFIG_COMPAT |
1135 | struct compat_xt_counters_info compat_tmp; | |
1da177e4 | 1136 | |
d6a2ba07 PM |
1137 | if (compat) { |
1138 | ptmp = &compat_tmp; | |
1139 | size = sizeof(struct compat_xt_counters_info); | |
1140 | } else | |
1141 | #endif | |
1142 | { | |
1143 | ptmp = &tmp; | |
1144 | size = sizeof(struct xt_counters_info); | |
1145 | } | |
1146 | ||
1147 | if (copy_from_user(ptmp, user, size) != 0) | |
1da177e4 LT |
1148 | return -EFAULT; |
1149 | ||
d6a2ba07 PM |
1150 | #ifdef CONFIG_COMPAT |
1151 | if (compat) { | |
1152 | num_counters = compat_tmp.num_counters; | |
1153 | name = compat_tmp.name; | |
1154 | } else | |
1155 | #endif | |
1156 | { | |
1157 | num_counters = tmp.num_counters; | |
1158 | name = tmp.name; | |
1159 | } | |
1160 | ||
1161 | if (len != size + num_counters * sizeof(struct xt_counters)) | |
1da177e4 LT |
1162 | return -EINVAL; |
1163 | ||
e12f8e29 | 1164 | paddc = vmalloc(len - size); |
1da177e4 LT |
1165 | if (!paddc) |
1166 | return -ENOMEM; | |
1167 | ||
d6a2ba07 | 1168 | if (copy_from_user(paddc, user + size, len - size) != 0) { |
1da177e4 LT |
1169 | ret = -EFAULT; |
1170 | goto free; | |
1171 | } | |
1172 | ||
ee999d8b | 1173 | t = xt_find_table_lock(net, NFPROTO_ARP, name); |
0cc8d8df | 1174 | if (IS_ERR_OR_NULL(t)) { |
6b7d31fc | 1175 | ret = t ? PTR_ERR(t) : -ENOENT; |
1da177e4 | 1176 | goto free; |
6b7d31fc | 1177 | } |
1da177e4 | 1178 | |
942e4a2b | 1179 | local_bh_disable(); |
2e4e6a17 | 1180 | private = t->private; |
d6a2ba07 | 1181 | if (private->number != num_counters) { |
1da177e4 LT |
1182 | ret = -EINVAL; |
1183 | goto unlock_up_free; | |
1184 | } | |
1185 | ||
1186 | i = 0; | |
482cfc31 | 1187 | |
7f5c6d4f | 1188 | addend = xt_write_recseq_begin(); |
482cfc31 | 1189 | xt_entry_foreach(iter, private->entries, private->size) { |
71ae0dff FW |
1190 | struct xt_counters *tmp; |
1191 | ||
1192 | tmp = xt_get_this_cpu_counter(&iter->counters); | |
1193 | ADD_COUNTER(*tmp, paddc[i].bcnt, paddc[i].pcnt); | |
0559518b JE |
1194 | ++i; |
1195 | } | |
7f5c6d4f | 1196 | xt_write_recseq_end(addend); |
1da177e4 | 1197 | unlock_up_free: |
942e4a2b | 1198 | local_bh_enable(); |
2e4e6a17 | 1199 | xt_table_unlock(t); |
6b7d31fc | 1200 | module_put(t->me); |
1da177e4 LT |
1201 | free: |
1202 | vfree(paddc); | |
1203 | ||
1204 | return ret; | |
1205 | } | |
1206 | ||
d6a2ba07 | 1207 | #ifdef CONFIG_COMPAT |
0559518b | 1208 | static inline void compat_release_entry(struct compat_arpt_entry *e) |
d6a2ba07 | 1209 | { |
87a2e70d | 1210 | struct xt_entry_target *t; |
d6a2ba07 | 1211 | |
d6a2ba07 PM |
1212 | t = compat_arpt_get_target(e); |
1213 | module_put(t->u.kernel.target->me); | |
d6a2ba07 PM |
1214 | } |
1215 | ||
1216 | static inline int | |
1217 | check_compat_entry_size_and_hooks(struct compat_arpt_entry *e, | |
1218 | struct xt_table_info *newinfo, | |
1219 | unsigned int *size, | |
d5d1baa1 JE |
1220 | const unsigned char *base, |
1221 | const unsigned char *limit, | |
1222 | const unsigned int *hook_entries, | |
1223 | const unsigned int *underflows, | |
d6a2ba07 PM |
1224 | const char *name) |
1225 | { | |
87a2e70d | 1226 | struct xt_entry_target *t; |
d6a2ba07 PM |
1227 | struct xt_target *target; |
1228 | unsigned int entry_offset; | |
1229 | int ret, off, h; | |
1230 | ||
1231 | duprintf("check_compat_entry_size_and_hooks %p\n", e); | |
3666ed1c JP |
1232 | if ((unsigned long)e % __alignof__(struct compat_arpt_entry) != 0 || |
1233 | (unsigned char *)e + sizeof(struct compat_arpt_entry) >= limit) { | |
d6a2ba07 PM |
1234 | duprintf("Bad offset %p, limit = %p\n", e, limit); |
1235 | return -EINVAL; | |
1236 | } | |
1237 | ||
1238 | if (e->next_offset < sizeof(struct compat_arpt_entry) + | |
1239 | sizeof(struct compat_xt_entry_target)) { | |
1240 | duprintf("checking: element %p size %u\n", | |
1241 | e, e->next_offset); | |
1242 | return -EINVAL; | |
1243 | } | |
1244 | ||
1245 | /* For purposes of check_entry casting the compat entry is fine */ | |
1246 | ret = check_entry((struct arpt_entry *)e, name); | |
1247 | if (ret) | |
1248 | return ret; | |
1249 | ||
1250 | off = sizeof(struct arpt_entry) - sizeof(struct compat_arpt_entry); | |
1251 | entry_offset = (void *)e - (void *)base; | |
1252 | ||
1253 | t = compat_arpt_get_target(e); | |
d2a7b6ba JE |
1254 | target = xt_request_find_target(NFPROTO_ARP, t->u.user.name, |
1255 | t->u.user.revision); | |
1256 | if (IS_ERR(target)) { | |
d6a2ba07 PM |
1257 | duprintf("check_compat_entry_size_and_hooks: `%s' not found\n", |
1258 | t->u.user.name); | |
d2a7b6ba | 1259 | ret = PTR_ERR(target); |
d6a2ba07 PM |
1260 | goto out; |
1261 | } | |
1262 | t->u.kernel.target = target; | |
1263 | ||
1264 | off += xt_compat_target_offset(target); | |
1265 | *size += off; | |
ee999d8b | 1266 | ret = xt_compat_add_offset(NFPROTO_ARP, entry_offset, off); |
d6a2ba07 PM |
1267 | if (ret) |
1268 | goto release_target; | |
1269 | ||
1270 | /* Check hooks & underflows */ | |
1271 | for (h = 0; h < NF_ARP_NUMHOOKS; h++) { | |
1272 | if ((unsigned char *)e - base == hook_entries[h]) | |
1273 | newinfo->hook_entry[h] = hook_entries[h]; | |
1274 | if ((unsigned char *)e - base == underflows[h]) | |
1275 | newinfo->underflow[h] = underflows[h]; | |
1276 | } | |
1277 | ||
1278 | /* Clear counters and comefrom */ | |
1279 | memset(&e->counters, 0, sizeof(e->counters)); | |
1280 | e->comefrom = 0; | |
d6a2ba07 PM |
1281 | return 0; |
1282 | ||
1283 | release_target: | |
1284 | module_put(t->u.kernel.target->me); | |
1285 | out: | |
1286 | return ret; | |
1287 | } | |
1288 | ||
1289 | static int | |
1290 | compat_copy_entry_from_user(struct compat_arpt_entry *e, void **dstptr, | |
1291 | unsigned int *size, const char *name, | |
1292 | struct xt_table_info *newinfo, unsigned char *base) | |
1293 | { | |
87a2e70d | 1294 | struct xt_entry_target *t; |
d6a2ba07 PM |
1295 | struct xt_target *target; |
1296 | struct arpt_entry *de; | |
1297 | unsigned int origsize; | |
1298 | int ret, h; | |
1299 | ||
1300 | ret = 0; | |
1301 | origsize = *size; | |
1302 | de = (struct arpt_entry *)*dstptr; | |
1303 | memcpy(de, e, sizeof(struct arpt_entry)); | |
1304 | memcpy(&de->counters, &e->counters, sizeof(e->counters)); | |
1305 | ||
1306 | *dstptr += sizeof(struct arpt_entry); | |
1307 | *size += sizeof(struct arpt_entry) - sizeof(struct compat_arpt_entry); | |
1308 | ||
1309 | de->target_offset = e->target_offset - (origsize - *size); | |
1310 | t = compat_arpt_get_target(e); | |
1311 | target = t->u.kernel.target; | |
1312 | xt_compat_target_from_user(t, dstptr, size); | |
1313 | ||
1314 | de->next_offset = e->next_offset - (origsize - *size); | |
1315 | for (h = 0; h < NF_ARP_NUMHOOKS; h++) { | |
1316 | if ((unsigned char *)de - base < newinfo->hook_entry[h]) | |
1317 | newinfo->hook_entry[h] -= origsize - *size; | |
1318 | if ((unsigned char *)de - base < newinfo->underflow[h]) | |
1319 | newinfo->underflow[h] -= origsize - *size; | |
1320 | } | |
1321 | return ret; | |
1322 | } | |
1323 | ||
d6a2ba07 PM |
1324 | static int translate_compat_table(const char *name, |
1325 | unsigned int valid_hooks, | |
1326 | struct xt_table_info **pinfo, | |
1327 | void **pentry0, | |
1328 | unsigned int total_size, | |
1329 | unsigned int number, | |
1330 | unsigned int *hook_entries, | |
1331 | unsigned int *underflows) | |
1332 | { | |
1333 | unsigned int i, j; | |
1334 | struct xt_table_info *newinfo, *info; | |
1335 | void *pos, *entry0, *entry1; | |
72b2b1dd JE |
1336 | struct compat_arpt_entry *iter0; |
1337 | struct arpt_entry *iter1; | |
d6a2ba07 | 1338 | unsigned int size; |
72b2b1dd | 1339 | int ret = 0; |
d6a2ba07 PM |
1340 | |
1341 | info = *pinfo; | |
1342 | entry0 = *pentry0; | |
1343 | size = total_size; | |
1344 | info->number = number; | |
1345 | ||
1346 | /* Init all hooks to impossible value. */ | |
1347 | for (i = 0; i < NF_ARP_NUMHOOKS; i++) { | |
1348 | info->hook_entry[i] = 0xFFFFFFFF; | |
1349 | info->underflow[i] = 0xFFFFFFFF; | |
1350 | } | |
1351 | ||
1352 | duprintf("translate_compat_table: size %u\n", info->size); | |
1353 | j = 0; | |
ee999d8b | 1354 | xt_compat_lock(NFPROTO_ARP); |
255d0dc3 | 1355 | xt_compat_init_offsets(NFPROTO_ARP, number); |
d6a2ba07 | 1356 | /* Walk through entries, checking offsets. */ |
72b2b1dd JE |
1357 | xt_entry_foreach(iter0, entry0, total_size) { |
1358 | ret = check_compat_entry_size_and_hooks(iter0, info, &size, | |
6b4ff2d7 JE |
1359 | entry0, |
1360 | entry0 + total_size, | |
1361 | hook_entries, | |
1362 | underflows, | |
1363 | name); | |
72b2b1dd | 1364 | if (ret != 0) |
0559518b JE |
1365 | goto out_unlock; |
1366 | ++j; | |
72b2b1dd | 1367 | } |
d6a2ba07 PM |
1368 | |
1369 | ret = -EINVAL; | |
1370 | if (j != number) { | |
1371 | duprintf("translate_compat_table: %u not %u entries\n", | |
1372 | j, number); | |
1373 | goto out_unlock; | |
1374 | } | |
1375 | ||
1376 | /* Check hooks all assigned */ | |
1377 | for (i = 0; i < NF_ARP_NUMHOOKS; i++) { | |
1378 | /* Only hooks which are valid */ | |
1379 | if (!(valid_hooks & (1 << i))) | |
1380 | continue; | |
1381 | if (info->hook_entry[i] == 0xFFFFFFFF) { | |
1382 | duprintf("Invalid hook entry %u %u\n", | |
1383 | i, hook_entries[i]); | |
1384 | goto out_unlock; | |
1385 | } | |
1386 | if (info->underflow[i] == 0xFFFFFFFF) { | |
1387 | duprintf("Invalid underflow %u %u\n", | |
1388 | i, underflows[i]); | |
1389 | goto out_unlock; | |
1390 | } | |
1391 | } | |
1392 | ||
1393 | ret = -ENOMEM; | |
1394 | newinfo = xt_alloc_table_info(size); | |
1395 | if (!newinfo) | |
1396 | goto out_unlock; | |
1397 | ||
1398 | newinfo->number = number; | |
1399 | for (i = 0; i < NF_ARP_NUMHOOKS; i++) { | |
1400 | newinfo->hook_entry[i] = info->hook_entry[i]; | |
1401 | newinfo->underflow[i] = info->underflow[i]; | |
1402 | } | |
482cfc31 | 1403 | entry1 = newinfo->entries; |
d6a2ba07 PM |
1404 | pos = entry1; |
1405 | size = total_size; | |
72b2b1dd | 1406 | xt_entry_foreach(iter0, entry0, total_size) { |
6b4ff2d7 JE |
1407 | ret = compat_copy_entry_from_user(iter0, &pos, &size, |
1408 | name, newinfo, entry1); | |
72b2b1dd JE |
1409 | if (ret != 0) |
1410 | break; | |
1411 | } | |
ee999d8b JE |
1412 | xt_compat_flush_offsets(NFPROTO_ARP); |
1413 | xt_compat_unlock(NFPROTO_ARP); | |
d6a2ba07 PM |
1414 | if (ret) |
1415 | goto free_newinfo; | |
1416 | ||
1417 | ret = -ELOOP; | |
1418 | if (!mark_source_chains(newinfo, valid_hooks, entry1)) | |
1419 | goto free_newinfo; | |
1420 | ||
1421 | i = 0; | |
72b2b1dd | 1422 | xt_entry_foreach(iter1, entry1, newinfo->size) { |
71ae0dff FW |
1423 | iter1->counters.pcnt = xt_percpu_counter_alloc(); |
1424 | if (IS_ERR_VALUE(iter1->counters.pcnt)) { | |
1425 | ret = -ENOMEM; | |
1426 | break; | |
1427 | } | |
1428 | ||
0559518b | 1429 | ret = check_target(iter1, name); |
71ae0dff FW |
1430 | if (ret != 0) { |
1431 | xt_percpu_counter_free(iter1->counters.pcnt); | |
72b2b1dd | 1432 | break; |
71ae0dff | 1433 | } |
0559518b | 1434 | ++i; |
cca77b7c FW |
1435 | if (strcmp(arpt_get_target(iter1)->u.user.name, |
1436 | XT_ERROR_TARGET) == 0) | |
1437 | ++newinfo->stacksize; | |
72b2b1dd | 1438 | } |
d6a2ba07 | 1439 | if (ret) { |
72b2b1dd JE |
1440 | /* |
1441 | * The first i matches need cleanup_entry (calls ->destroy) | |
1442 | * because they had called ->check already. The other j-i | |
1443 | * entries need only release. | |
1444 | */ | |
1445 | int skip = i; | |
d6a2ba07 | 1446 | j -= i; |
72b2b1dd JE |
1447 | xt_entry_foreach(iter0, entry0, newinfo->size) { |
1448 | if (skip-- > 0) | |
1449 | continue; | |
0559518b | 1450 | if (j-- == 0) |
72b2b1dd | 1451 | break; |
0559518b | 1452 | compat_release_entry(iter0); |
72b2b1dd | 1453 | } |
0559518b JE |
1454 | xt_entry_foreach(iter1, entry1, newinfo->size) { |
1455 | if (i-- == 0) | |
72b2b1dd | 1456 | break; |
0559518b JE |
1457 | cleanup_entry(iter1); |
1458 | } | |
d6a2ba07 PM |
1459 | xt_free_table_info(newinfo); |
1460 | return ret; | |
1461 | } | |
1462 | ||
d6a2ba07 PM |
1463 | *pinfo = newinfo; |
1464 | *pentry0 = entry1; | |
1465 | xt_free_table_info(info); | |
1466 | return 0; | |
1467 | ||
1468 | free_newinfo: | |
1469 | xt_free_table_info(newinfo); | |
1470 | out: | |
0559518b JE |
1471 | xt_entry_foreach(iter0, entry0, total_size) { |
1472 | if (j-- == 0) | |
72b2b1dd | 1473 | break; |
0559518b JE |
1474 | compat_release_entry(iter0); |
1475 | } | |
d6a2ba07 PM |
1476 | return ret; |
1477 | out_unlock: | |
ee999d8b JE |
1478 | xt_compat_flush_offsets(NFPROTO_ARP); |
1479 | xt_compat_unlock(NFPROTO_ARP); | |
d6a2ba07 PM |
1480 | goto out; |
1481 | } | |
1482 | ||
1483 | struct compat_arpt_replace { | |
12b00c2c | 1484 | char name[XT_TABLE_MAXNAMELEN]; |
d6a2ba07 PM |
1485 | u32 valid_hooks; |
1486 | u32 num_entries; | |
1487 | u32 size; | |
1488 | u32 hook_entry[NF_ARP_NUMHOOKS]; | |
1489 | u32 underflow[NF_ARP_NUMHOOKS]; | |
1490 | u32 num_counters; | |
1491 | compat_uptr_t counters; | |
1492 | struct compat_arpt_entry entries[0]; | |
1493 | }; | |
1494 | ||
79df341a AD |
1495 | static int compat_do_replace(struct net *net, void __user *user, |
1496 | unsigned int len) | |
d6a2ba07 PM |
1497 | { |
1498 | int ret; | |
1499 | struct compat_arpt_replace tmp; | |
1500 | struct xt_table_info *newinfo; | |
1501 | void *loc_cpu_entry; | |
72b2b1dd | 1502 | struct arpt_entry *iter; |
d6a2ba07 PM |
1503 | |
1504 | if (copy_from_user(&tmp, user, sizeof(tmp)) != 0) | |
1505 | return -EFAULT; | |
1506 | ||
1507 | /* overflow check */ | |
1508 | if (tmp.size >= INT_MAX / num_possible_cpus()) | |
1509 | return -ENOMEM; | |
1510 | if (tmp.num_counters >= INT_MAX / sizeof(struct xt_counters)) | |
1511 | return -ENOMEM; | |
1086bbe9 DJ |
1512 | if (tmp.num_counters == 0) |
1513 | return -EINVAL; | |
1514 | ||
42eab94f | 1515 | tmp.name[sizeof(tmp.name)-1] = 0; |
d6a2ba07 PM |
1516 | |
1517 | newinfo = xt_alloc_table_info(tmp.size); | |
1518 | if (!newinfo) | |
1519 | return -ENOMEM; | |
1520 | ||
482cfc31 | 1521 | loc_cpu_entry = newinfo->entries; |
d6a2ba07 PM |
1522 | if (copy_from_user(loc_cpu_entry, user + sizeof(tmp), tmp.size) != 0) { |
1523 | ret = -EFAULT; | |
1524 | goto free_newinfo; | |
1525 | } | |
1526 | ||
1527 | ret = translate_compat_table(tmp.name, tmp.valid_hooks, | |
1528 | &newinfo, &loc_cpu_entry, tmp.size, | |
1529 | tmp.num_entries, tmp.hook_entry, | |
1530 | tmp.underflow); | |
1531 | if (ret != 0) | |
1532 | goto free_newinfo; | |
1533 | ||
1534 | duprintf("compat_do_replace: Translated table\n"); | |
1535 | ||
79df341a | 1536 | ret = __do_replace(net, tmp.name, tmp.valid_hooks, newinfo, |
d6a2ba07 PM |
1537 | tmp.num_counters, compat_ptr(tmp.counters)); |
1538 | if (ret) | |
1539 | goto free_newinfo_untrans; | |
1540 | return 0; | |
1541 | ||
1542 | free_newinfo_untrans: | |
72b2b1dd | 1543 | xt_entry_foreach(iter, loc_cpu_entry, newinfo->size) |
0559518b | 1544 | cleanup_entry(iter); |
d6a2ba07 PM |
1545 | free_newinfo: |
1546 | xt_free_table_info(newinfo); | |
1547 | return ret; | |
1548 | } | |
1549 | ||
1550 | static int compat_do_arpt_set_ctl(struct sock *sk, int cmd, void __user *user, | |
1551 | unsigned int len) | |
1552 | { | |
1553 | int ret; | |
1554 | ||
52e804c6 | 1555 | if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) |
d6a2ba07 PM |
1556 | return -EPERM; |
1557 | ||
1558 | switch (cmd) { | |
1559 | case ARPT_SO_SET_REPLACE: | |
3b1e0a65 | 1560 | ret = compat_do_replace(sock_net(sk), user, len); |
d6a2ba07 PM |
1561 | break; |
1562 | ||
1563 | case ARPT_SO_SET_ADD_COUNTERS: | |
3b1e0a65 | 1564 | ret = do_add_counters(sock_net(sk), user, len, 1); |
d6a2ba07 PM |
1565 | break; |
1566 | ||
1567 | default: | |
1568 | duprintf("do_arpt_set_ctl: unknown request %i\n", cmd); | |
1569 | ret = -EINVAL; | |
1570 | } | |
1571 | ||
1572 | return ret; | |
1573 | } | |
1574 | ||
1575 | static int compat_copy_entry_to_user(struct arpt_entry *e, void __user **dstptr, | |
1576 | compat_uint_t *size, | |
1577 | struct xt_counters *counters, | |
0559518b | 1578 | unsigned int i) |
d6a2ba07 | 1579 | { |
87a2e70d | 1580 | struct xt_entry_target *t; |
d6a2ba07 PM |
1581 | struct compat_arpt_entry __user *ce; |
1582 | u_int16_t target_offset, next_offset; | |
1583 | compat_uint_t origsize; | |
1584 | int ret; | |
1585 | ||
d6a2ba07 PM |
1586 | origsize = *size; |
1587 | ce = (struct compat_arpt_entry __user *)*dstptr; | |
0559518b JE |
1588 | if (copy_to_user(ce, e, sizeof(struct arpt_entry)) != 0 || |
1589 | copy_to_user(&ce->counters, &counters[i], | |
1590 | sizeof(counters[i])) != 0) | |
1591 | return -EFAULT; | |
d6a2ba07 PM |
1592 | |
1593 | *dstptr += sizeof(struct compat_arpt_entry); | |
1594 | *size -= sizeof(struct arpt_entry) - sizeof(struct compat_arpt_entry); | |
1595 | ||
1596 | target_offset = e->target_offset - (origsize - *size); | |
1597 | ||
1598 | t = arpt_get_target(e); | |
1599 | ret = xt_compat_target_to_user(t, dstptr, size); | |
1600 | if (ret) | |
0559518b | 1601 | return ret; |
d6a2ba07 | 1602 | next_offset = e->next_offset - (origsize - *size); |
0559518b JE |
1603 | if (put_user(target_offset, &ce->target_offset) != 0 || |
1604 | put_user(next_offset, &ce->next_offset) != 0) | |
1605 | return -EFAULT; | |
d6a2ba07 | 1606 | return 0; |
d6a2ba07 PM |
1607 | } |
1608 | ||
1609 | static int compat_copy_entries_to_user(unsigned int total_size, | |
4abff077 | 1610 | struct xt_table *table, |
d6a2ba07 PM |
1611 | void __user *userptr) |
1612 | { | |
1613 | struct xt_counters *counters; | |
5452e425 | 1614 | const struct xt_table_info *private = table->private; |
d6a2ba07 PM |
1615 | void __user *pos; |
1616 | unsigned int size; | |
1617 | int ret = 0; | |
d6a2ba07 | 1618 | unsigned int i = 0; |
72b2b1dd | 1619 | struct arpt_entry *iter; |
d6a2ba07 PM |
1620 | |
1621 | counters = alloc_counters(table); | |
1622 | if (IS_ERR(counters)) | |
1623 | return PTR_ERR(counters); | |
1624 | ||
d6a2ba07 PM |
1625 | pos = userptr; |
1626 | size = total_size; | |
482cfc31 | 1627 | xt_entry_foreach(iter, private->entries, total_size) { |
72b2b1dd | 1628 | ret = compat_copy_entry_to_user(iter, &pos, |
6b4ff2d7 | 1629 | &size, counters, i++); |
72b2b1dd JE |
1630 | if (ret != 0) |
1631 | break; | |
1632 | } | |
d6a2ba07 PM |
1633 | vfree(counters); |
1634 | return ret; | |
1635 | } | |
1636 | ||
1637 | struct compat_arpt_get_entries { | |
12b00c2c | 1638 | char name[XT_TABLE_MAXNAMELEN]; |
d6a2ba07 PM |
1639 | compat_uint_t size; |
1640 | struct compat_arpt_entry entrytable[0]; | |
1641 | }; | |
1642 | ||
79df341a AD |
1643 | static int compat_get_entries(struct net *net, |
1644 | struct compat_arpt_get_entries __user *uptr, | |
d6a2ba07 PM |
1645 | int *len) |
1646 | { | |
1647 | int ret; | |
1648 | struct compat_arpt_get_entries get; | |
4abff077 | 1649 | struct xt_table *t; |
d6a2ba07 PM |
1650 | |
1651 | if (*len < sizeof(get)) { | |
1652 | duprintf("compat_get_entries: %u < %zu\n", *len, sizeof(get)); | |
1653 | return -EINVAL; | |
1654 | } | |
1655 | if (copy_from_user(&get, uptr, sizeof(get)) != 0) | |
1656 | return -EFAULT; | |
1657 | if (*len != sizeof(struct compat_arpt_get_entries) + get.size) { | |
1658 | duprintf("compat_get_entries: %u != %zu\n", | |
1659 | *len, sizeof(get) + get.size); | |
1660 | return -EINVAL; | |
1661 | } | |
1662 | ||
ee999d8b JE |
1663 | xt_compat_lock(NFPROTO_ARP); |
1664 | t = xt_find_table_lock(net, NFPROTO_ARP, get.name); | |
0cc8d8df | 1665 | if (!IS_ERR_OR_NULL(t)) { |
5452e425 | 1666 | const struct xt_table_info *private = t->private; |
d6a2ba07 PM |
1667 | struct xt_table_info info; |
1668 | ||
1669 | duprintf("t->private->number = %u\n", private->number); | |
1670 | ret = compat_table_info(private, &info); | |
1671 | if (!ret && get.size == info.size) { | |
1672 | ret = compat_copy_entries_to_user(private->size, | |
1673 | t, uptr->entrytable); | |
1674 | } else if (!ret) { | |
1675 | duprintf("compat_get_entries: I've got %u not %u!\n", | |
1676 | private->size, get.size); | |
544473c1 | 1677 | ret = -EAGAIN; |
d6a2ba07 | 1678 | } |
ee999d8b | 1679 | xt_compat_flush_offsets(NFPROTO_ARP); |
d6a2ba07 PM |
1680 | module_put(t->me); |
1681 | xt_table_unlock(t); | |
1682 | } else | |
1683 | ret = t ? PTR_ERR(t) : -ENOENT; | |
1684 | ||
ee999d8b | 1685 | xt_compat_unlock(NFPROTO_ARP); |
d6a2ba07 PM |
1686 | return ret; |
1687 | } | |
1688 | ||
1689 | static int do_arpt_get_ctl(struct sock *, int, void __user *, int *); | |
1690 | ||
1691 | static int compat_do_arpt_get_ctl(struct sock *sk, int cmd, void __user *user, | |
1692 | int *len) | |
1693 | { | |
1694 | int ret; | |
1695 | ||
52e804c6 | 1696 | if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) |
d6a2ba07 PM |
1697 | return -EPERM; |
1698 | ||
1699 | switch (cmd) { | |
1700 | case ARPT_SO_GET_INFO: | |
3b1e0a65 | 1701 | ret = get_info(sock_net(sk), user, len, 1); |
d6a2ba07 PM |
1702 | break; |
1703 | case ARPT_SO_GET_ENTRIES: | |
3b1e0a65 | 1704 | ret = compat_get_entries(sock_net(sk), user, len); |
d6a2ba07 PM |
1705 | break; |
1706 | default: | |
1707 | ret = do_arpt_get_ctl(sk, cmd, user, len); | |
1708 | } | |
1709 | return ret; | |
1710 | } | |
1711 | #endif | |
1712 | ||
1da177e4 LT |
1713 | static int do_arpt_set_ctl(struct sock *sk, int cmd, void __user *user, unsigned int len) |
1714 | { | |
1715 | int ret; | |
1716 | ||
52e804c6 | 1717 | if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) |
1da177e4 LT |
1718 | return -EPERM; |
1719 | ||
1720 | switch (cmd) { | |
1721 | case ARPT_SO_SET_REPLACE: | |
3b1e0a65 | 1722 | ret = do_replace(sock_net(sk), user, len); |
1da177e4 LT |
1723 | break; |
1724 | ||
1725 | case ARPT_SO_SET_ADD_COUNTERS: | |
3b1e0a65 | 1726 | ret = do_add_counters(sock_net(sk), user, len, 0); |
1da177e4 LT |
1727 | break; |
1728 | ||
1729 | default: | |
1730 | duprintf("do_arpt_set_ctl: unknown request %i\n", cmd); | |
1731 | ret = -EINVAL; | |
1732 | } | |
1733 | ||
1734 | return ret; | |
1735 | } | |
1736 | ||
1737 | static int do_arpt_get_ctl(struct sock *sk, int cmd, void __user *user, int *len) | |
1738 | { | |
1739 | int ret; | |
1740 | ||
52e804c6 | 1741 | if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) |
1da177e4 LT |
1742 | return -EPERM; |
1743 | ||
1744 | switch (cmd) { | |
41acd975 | 1745 | case ARPT_SO_GET_INFO: |
3b1e0a65 | 1746 | ret = get_info(sock_net(sk), user, len, 0); |
41acd975 | 1747 | break; |
1da177e4 | 1748 | |
11f6dff8 | 1749 | case ARPT_SO_GET_ENTRIES: |
3b1e0a65 | 1750 | ret = get_entries(sock_net(sk), user, len); |
1da177e4 | 1751 | break; |
1da177e4 | 1752 | |
6b7d31fc | 1753 | case ARPT_SO_GET_REVISION_TARGET: { |
2e4e6a17 | 1754 | struct xt_get_revision rev; |
6b7d31fc HW |
1755 | |
1756 | if (*len != sizeof(rev)) { | |
1757 | ret = -EINVAL; | |
1758 | break; | |
1759 | } | |
1760 | if (copy_from_user(&rev, user, sizeof(rev)) != 0) { | |
1761 | ret = -EFAULT; | |
1762 | break; | |
1763 | } | |
42eab94f | 1764 | rev.name[sizeof(rev.name)-1] = 0; |
6b7d31fc | 1765 | |
ee999d8b | 1766 | try_then_request_module(xt_find_revision(NFPROTO_ARP, rev.name, |
2e4e6a17 | 1767 | rev.revision, 1, &ret), |
6b7d31fc HW |
1768 | "arpt_%s", rev.name); |
1769 | break; | |
1770 | } | |
1771 | ||
1da177e4 LT |
1772 | default: |
1773 | duprintf("do_arpt_get_ctl: unknown request %i\n", cmd); | |
1774 | ret = -EINVAL; | |
1775 | } | |
1776 | ||
1777 | return ret; | |
1778 | } | |
1779 | ||
35aad0ff JE |
1780 | struct xt_table *arpt_register_table(struct net *net, |
1781 | const struct xt_table *table, | |
4abff077 | 1782 | const struct arpt_replace *repl) |
1da177e4 LT |
1783 | { |
1784 | int ret; | |
2e4e6a17 | 1785 | struct xt_table_info *newinfo; |
f3c5c1bf | 1786 | struct xt_table_info bootstrap = {0}; |
31836064 | 1787 | void *loc_cpu_entry; |
a98da11d | 1788 | struct xt_table *new_table; |
1da177e4 | 1789 | |
2e4e6a17 | 1790 | newinfo = xt_alloc_table_info(repl->size); |
1da177e4 LT |
1791 | if (!newinfo) { |
1792 | ret = -ENOMEM; | |
44d34e72 | 1793 | goto out; |
1da177e4 | 1794 | } |
31836064 | 1795 | |
482cfc31 | 1796 | loc_cpu_entry = newinfo->entries; |
31836064 | 1797 | memcpy(loc_cpu_entry, repl->entries, repl->size); |
1da177e4 | 1798 | |
0f234214 | 1799 | ret = translate_table(newinfo, loc_cpu_entry, repl); |
1da177e4 | 1800 | duprintf("arpt_register_table: translate table gives %d\n", ret); |
44d34e72 AD |
1801 | if (ret != 0) |
1802 | goto out_free; | |
1da177e4 | 1803 | |
79df341a | 1804 | new_table = xt_register_table(net, table, &bootstrap, newinfo); |
a98da11d | 1805 | if (IS_ERR(new_table)) { |
44d34e72 AD |
1806 | ret = PTR_ERR(new_table); |
1807 | goto out_free; | |
1da177e4 | 1808 | } |
44d34e72 | 1809 | return new_table; |
1da177e4 | 1810 | |
44d34e72 AD |
1811 | out_free: |
1812 | xt_free_table_info(newinfo); | |
1813 | out: | |
1814 | return ERR_PTR(ret); | |
1da177e4 LT |
1815 | } |
1816 | ||
4abff077 | 1817 | void arpt_unregister_table(struct xt_table *table) |
1da177e4 | 1818 | { |
2e4e6a17 | 1819 | struct xt_table_info *private; |
31836064 | 1820 | void *loc_cpu_entry; |
df200969 | 1821 | struct module *table_owner = table->me; |
72b2b1dd | 1822 | struct arpt_entry *iter; |
31836064 | 1823 | |
2e4e6a17 | 1824 | private = xt_unregister_table(table); |
1da177e4 LT |
1825 | |
1826 | /* Decrease module usage counts and free resources */ | |
482cfc31 | 1827 | loc_cpu_entry = private->entries; |
72b2b1dd | 1828 | xt_entry_foreach(iter, loc_cpu_entry, private->size) |
0559518b | 1829 | cleanup_entry(iter); |
df200969 AD |
1830 | if (private->number > private->initial_entries) |
1831 | module_put(table_owner); | |
2e4e6a17 | 1832 | xt_free_table_info(private); |
1da177e4 LT |
1833 | } |
1834 | ||
1835 | /* The built-in targets: standard (NULL) and error. */ | |
4538506b JE |
1836 | static struct xt_target arpt_builtin_tg[] __read_mostly = { |
1837 | { | |
243bf6e2 | 1838 | .name = XT_STANDARD_TARGET, |
4538506b JE |
1839 | .targetsize = sizeof(int), |
1840 | .family = NFPROTO_ARP, | |
d6a2ba07 | 1841 | #ifdef CONFIG_COMPAT |
4538506b JE |
1842 | .compatsize = sizeof(compat_int_t), |
1843 | .compat_from_user = compat_standard_from_user, | |
1844 | .compat_to_user = compat_standard_to_user, | |
d6a2ba07 | 1845 | #endif |
4538506b JE |
1846 | }, |
1847 | { | |
243bf6e2 | 1848 | .name = XT_ERROR_TARGET, |
4538506b | 1849 | .target = arpt_error, |
12b00c2c | 1850 | .targetsize = XT_FUNCTION_MAXNAMELEN, |
4538506b JE |
1851 | .family = NFPROTO_ARP, |
1852 | }, | |
1da177e4 LT |
1853 | }; |
1854 | ||
1855 | static struct nf_sockopt_ops arpt_sockopts = { | |
1856 | .pf = PF_INET, | |
1857 | .set_optmin = ARPT_BASE_CTL, | |
1858 | .set_optmax = ARPT_SO_SET_MAX+1, | |
1859 | .set = do_arpt_set_ctl, | |
d6a2ba07 PM |
1860 | #ifdef CONFIG_COMPAT |
1861 | .compat_set = compat_do_arpt_set_ctl, | |
1862 | #endif | |
1da177e4 LT |
1863 | .get_optmin = ARPT_BASE_CTL, |
1864 | .get_optmax = ARPT_SO_GET_MAX+1, | |
1865 | .get = do_arpt_get_ctl, | |
d6a2ba07 PM |
1866 | #ifdef CONFIG_COMPAT |
1867 | .compat_get = compat_do_arpt_get_ctl, | |
1868 | #endif | |
16fcec35 | 1869 | .owner = THIS_MODULE, |
1da177e4 LT |
1870 | }; |
1871 | ||
3cb609d5 AD |
1872 | static int __net_init arp_tables_net_init(struct net *net) |
1873 | { | |
ee999d8b | 1874 | return xt_proto_init(net, NFPROTO_ARP); |
3cb609d5 AD |
1875 | } |
1876 | ||
1877 | static void __net_exit arp_tables_net_exit(struct net *net) | |
1878 | { | |
ee999d8b | 1879 | xt_proto_fini(net, NFPROTO_ARP); |
3cb609d5 AD |
1880 | } |
1881 | ||
1882 | static struct pernet_operations arp_tables_net_ops = { | |
1883 | .init = arp_tables_net_init, | |
1884 | .exit = arp_tables_net_exit, | |
1885 | }; | |
1886 | ||
65b4b4e8 | 1887 | static int __init arp_tables_init(void) |
1da177e4 LT |
1888 | { |
1889 | int ret; | |
1890 | ||
3cb609d5 | 1891 | ret = register_pernet_subsys(&arp_tables_net_ops); |
0eff66e6 PM |
1892 | if (ret < 0) |
1893 | goto err1; | |
2e4e6a17 | 1894 | |
25985edc | 1895 | /* No one else will be downing sem now, so we won't sleep */ |
4538506b | 1896 | ret = xt_register_targets(arpt_builtin_tg, ARRAY_SIZE(arpt_builtin_tg)); |
0eff66e6 PM |
1897 | if (ret < 0) |
1898 | goto err2; | |
1da177e4 LT |
1899 | |
1900 | /* Register setsockopt */ | |
1901 | ret = nf_register_sockopt(&arpt_sockopts); | |
0eff66e6 PM |
1902 | if (ret < 0) |
1903 | goto err4; | |
1da177e4 | 1904 | |
a887c1c1 | 1905 | printk(KERN_INFO "arp_tables: (C) 2002 David S. Miller\n"); |
1da177e4 | 1906 | return 0; |
0eff66e6 PM |
1907 | |
1908 | err4: | |
4538506b | 1909 | xt_unregister_targets(arpt_builtin_tg, ARRAY_SIZE(arpt_builtin_tg)); |
0eff66e6 | 1910 | err2: |
3cb609d5 | 1911 | unregister_pernet_subsys(&arp_tables_net_ops); |
0eff66e6 PM |
1912 | err1: |
1913 | return ret; | |
1da177e4 LT |
1914 | } |
1915 | ||
65b4b4e8 | 1916 | static void __exit arp_tables_fini(void) |
1da177e4 LT |
1917 | { |
1918 | nf_unregister_sockopt(&arpt_sockopts); | |
4538506b | 1919 | xt_unregister_targets(arpt_builtin_tg, ARRAY_SIZE(arpt_builtin_tg)); |
3cb609d5 | 1920 | unregister_pernet_subsys(&arp_tables_net_ops); |
1da177e4 LT |
1921 | } |
1922 | ||
1923 | EXPORT_SYMBOL(arpt_register_table); | |
1924 | EXPORT_SYMBOL(arpt_unregister_table); | |
1925 | EXPORT_SYMBOL(arpt_do_table); | |
1da177e4 | 1926 | |
65b4b4e8 AM |
1927 | module_init(arp_tables_init); |
1928 | module_exit(arp_tables_fini); |