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) | |
9 | * | |
10 | */ | |
11 | ||
12 | #include <linux/config.h> | |
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> | |
23 | ||
24 | #include <asm/uaccess.h> | |
25 | #include <asm/semaphore.h> | |
26 | ||
27 | #include <linux/netfilter_arp/arp_tables.h> | |
28 | ||
29 | MODULE_LICENSE("GPL"); | |
30 | MODULE_AUTHOR("David S. Miller <davem@redhat.com>"); | |
31 | MODULE_DESCRIPTION("arptables core"); | |
32 | ||
33 | /*#define DEBUG_ARP_TABLES*/ | |
34 | /*#define DEBUG_ARP_TABLES_USER*/ | |
35 | ||
36 | #ifdef DEBUG_ARP_TABLES | |
37 | #define dprintf(format, args...) printk(format , ## args) | |
38 | #else | |
39 | #define dprintf(format, args...) | |
40 | #endif | |
41 | ||
42 | #ifdef DEBUG_ARP_TABLES_USER | |
43 | #define duprintf(format, args...) printk(format , ## args) | |
44 | #else | |
45 | #define duprintf(format, args...) | |
46 | #endif | |
47 | ||
48 | #ifdef CONFIG_NETFILTER_DEBUG | |
49 | #define ARP_NF_ASSERT(x) \ | |
50 | do { \ | |
51 | if (!(x)) \ | |
52 | printk("ARP_NF_ASSERT: %s:%s:%u\n", \ | |
53 | __FUNCTION__, __FILE__, __LINE__); \ | |
54 | } while(0) | |
55 | #else | |
56 | #define ARP_NF_ASSERT(x) | |
57 | #endif | |
58 | #define SMP_ALIGN(x) (((x) + SMP_CACHE_BYTES-1) & ~(SMP_CACHE_BYTES-1)) | |
59 | ||
60 | static DECLARE_MUTEX(arpt_mutex); | |
61 | ||
62 | #define ASSERT_READ_LOCK(x) ARP_NF_ASSERT(down_trylock(&arpt_mutex) != 0) | |
63 | #define ASSERT_WRITE_LOCK(x) ARP_NF_ASSERT(down_trylock(&arpt_mutex) != 0) | |
1da177e4 LT |
64 | #include <linux/netfilter_ipv4/listhelp.h> |
65 | ||
66 | struct arpt_table_info { | |
67 | unsigned int size; | |
68 | unsigned int number; | |
69 | unsigned int initial_entries; | |
70 | unsigned int hook_entry[NF_ARP_NUMHOOKS]; | |
71 | unsigned int underflow[NF_ARP_NUMHOOKS]; | |
31836064 | 72 | void *entries[NR_CPUS]; |
1da177e4 LT |
73 | }; |
74 | ||
75 | static LIST_HEAD(arpt_target); | |
76 | static LIST_HEAD(arpt_tables); | |
31836064 | 77 | #define SET_COUNTER(c,b,p) do { (c).bcnt = (b); (c).pcnt = (p); } while(0) |
1da177e4 LT |
78 | #define ADD_COUNTER(c,b,p) do { (c).bcnt += (b); (c).pcnt += (p); } while(0) |
79 | ||
1da177e4 LT |
80 | static inline int arp_devaddr_compare(const struct arpt_devaddr_info *ap, |
81 | char *hdr_addr, int len) | |
82 | { | |
83 | int i, ret; | |
84 | ||
85 | if (len > ARPT_DEV_ADDR_LEN_MAX) | |
86 | len = ARPT_DEV_ADDR_LEN_MAX; | |
87 | ||
88 | ret = 0; | |
89 | for (i = 0; i < len; i++) | |
90 | ret |= (hdr_addr[i] ^ ap->addr[i]) & ap->mask[i]; | |
91 | ||
92 | return (ret != 0); | |
93 | } | |
94 | ||
95 | /* Returns whether packet matches rule or not. */ | |
96 | static inline int arp_packet_match(const struct arphdr *arphdr, | |
97 | struct net_device *dev, | |
98 | const char *indev, | |
99 | const char *outdev, | |
100 | const struct arpt_arp *arpinfo) | |
101 | { | |
102 | char *arpptr = (char *)(arphdr + 1); | |
103 | char *src_devaddr, *tgt_devaddr; | |
104 | u32 src_ipaddr, tgt_ipaddr; | |
105 | int i, ret; | |
106 | ||
107 | #define FWINV(bool,invflg) ((bool) ^ !!(arpinfo->invflags & invflg)) | |
108 | ||
109 | if (FWINV((arphdr->ar_op & arpinfo->arpop_mask) != arpinfo->arpop, | |
110 | ARPT_INV_ARPOP)) { | |
111 | dprintf("ARP operation field mismatch.\n"); | |
112 | dprintf("ar_op: %04x info->arpop: %04x info->arpop_mask: %04x\n", | |
113 | arphdr->ar_op, arpinfo->arpop, arpinfo->arpop_mask); | |
114 | return 0; | |
115 | } | |
116 | ||
117 | if (FWINV((arphdr->ar_hrd & arpinfo->arhrd_mask) != arpinfo->arhrd, | |
118 | ARPT_INV_ARPHRD)) { | |
119 | dprintf("ARP hardware address format mismatch.\n"); | |
120 | dprintf("ar_hrd: %04x info->arhrd: %04x info->arhrd_mask: %04x\n", | |
121 | arphdr->ar_hrd, arpinfo->arhrd, arpinfo->arhrd_mask); | |
122 | return 0; | |
123 | } | |
124 | ||
125 | if (FWINV((arphdr->ar_pro & arpinfo->arpro_mask) != arpinfo->arpro, | |
126 | ARPT_INV_ARPPRO)) { | |
127 | dprintf("ARP protocol address format mismatch.\n"); | |
128 | dprintf("ar_pro: %04x info->arpro: %04x info->arpro_mask: %04x\n", | |
129 | arphdr->ar_pro, arpinfo->arpro, arpinfo->arpro_mask); | |
130 | return 0; | |
131 | } | |
132 | ||
133 | if (FWINV((arphdr->ar_hln & arpinfo->arhln_mask) != arpinfo->arhln, | |
134 | ARPT_INV_ARPHLN)) { | |
135 | dprintf("ARP hardware address length mismatch.\n"); | |
136 | dprintf("ar_hln: %02x info->arhln: %02x info->arhln_mask: %02x\n", | |
137 | arphdr->ar_hln, arpinfo->arhln, arpinfo->arhln_mask); | |
138 | return 0; | |
139 | } | |
140 | ||
141 | src_devaddr = arpptr; | |
142 | arpptr += dev->addr_len; | |
143 | memcpy(&src_ipaddr, arpptr, sizeof(u32)); | |
144 | arpptr += sizeof(u32); | |
145 | tgt_devaddr = arpptr; | |
146 | arpptr += dev->addr_len; | |
147 | memcpy(&tgt_ipaddr, arpptr, sizeof(u32)); | |
148 | ||
149 | if (FWINV(arp_devaddr_compare(&arpinfo->src_devaddr, src_devaddr, dev->addr_len), | |
150 | ARPT_INV_SRCDEVADDR) || | |
151 | FWINV(arp_devaddr_compare(&arpinfo->tgt_devaddr, tgt_devaddr, dev->addr_len), | |
152 | ARPT_INV_TGTDEVADDR)) { | |
153 | dprintf("Source or target device address mismatch.\n"); | |
154 | ||
155 | return 0; | |
156 | } | |
157 | ||
158 | if (FWINV((src_ipaddr & arpinfo->smsk.s_addr) != arpinfo->src.s_addr, | |
159 | ARPT_INV_SRCIP) || | |
160 | FWINV(((tgt_ipaddr & arpinfo->tmsk.s_addr) != arpinfo->tgt.s_addr), | |
161 | ARPT_INV_TGTIP)) { | |
162 | dprintf("Source or target IP address mismatch.\n"); | |
163 | ||
164 | dprintf("SRC: %u.%u.%u.%u. Mask: %u.%u.%u.%u. Target: %u.%u.%u.%u.%s\n", | |
165 | NIPQUAD(src_ipaddr), | |
166 | NIPQUAD(arpinfo->smsk.s_addr), | |
167 | NIPQUAD(arpinfo->src.s_addr), | |
168 | arpinfo->invflags & ARPT_INV_SRCIP ? " (INV)" : ""); | |
169 | dprintf("TGT: %u.%u.%u.%u Mask: %u.%u.%u.%u Target: %u.%u.%u.%u.%s\n", | |
170 | NIPQUAD(tgt_ipaddr), | |
171 | NIPQUAD(arpinfo->tmsk.s_addr), | |
172 | NIPQUAD(arpinfo->tgt.s_addr), | |
173 | arpinfo->invflags & ARPT_INV_TGTIP ? " (INV)" : ""); | |
174 | return 0; | |
175 | } | |
176 | ||
177 | /* Look for ifname matches. */ | |
178 | for (i = 0, ret = 0; i < IFNAMSIZ; i++) { | |
179 | ret |= (indev[i] ^ arpinfo->iniface[i]) | |
180 | & arpinfo->iniface_mask[i]; | |
181 | } | |
182 | ||
183 | if (FWINV(ret != 0, ARPT_INV_VIA_IN)) { | |
184 | dprintf("VIA in mismatch (%s vs %s).%s\n", | |
185 | indev, arpinfo->iniface, | |
186 | arpinfo->invflags&ARPT_INV_VIA_IN ?" (INV)":""); | |
187 | return 0; | |
188 | } | |
189 | ||
190 | for (i = 0, ret = 0; i < IFNAMSIZ/sizeof(unsigned long); i++) { | |
191 | unsigned long odev; | |
192 | memcpy(&odev, outdev + i*sizeof(unsigned long), | |
193 | sizeof(unsigned long)); | |
194 | ret |= (odev | |
195 | ^ ((const unsigned long *)arpinfo->outiface)[i]) | |
196 | & ((const unsigned long *)arpinfo->outiface_mask)[i]; | |
197 | } | |
198 | ||
199 | if (FWINV(ret != 0, ARPT_INV_VIA_OUT)) { | |
200 | dprintf("VIA out mismatch (%s vs %s).%s\n", | |
201 | outdev, arpinfo->outiface, | |
202 | arpinfo->invflags&ARPT_INV_VIA_OUT ?" (INV)":""); | |
203 | return 0; | |
204 | } | |
205 | ||
206 | return 1; | |
207 | } | |
208 | ||
209 | static inline int arp_checkentry(const struct arpt_arp *arp) | |
210 | { | |
211 | if (arp->flags & ~ARPT_F_MASK) { | |
212 | duprintf("Unknown flag bits set: %08X\n", | |
213 | arp->flags & ~ARPT_F_MASK); | |
214 | return 0; | |
215 | } | |
216 | if (arp->invflags & ~ARPT_INV_MASK) { | |
217 | duprintf("Unknown invflag bits set: %08X\n", | |
218 | arp->invflags & ~ARPT_INV_MASK); | |
219 | return 0; | |
220 | } | |
221 | ||
222 | return 1; | |
223 | } | |
224 | ||
225 | static unsigned int arpt_error(struct sk_buff **pskb, | |
226 | unsigned int hooknum, | |
227 | const struct net_device *in, | |
228 | const struct net_device *out, | |
229 | const void *targinfo, | |
230 | void *userinfo) | |
231 | { | |
232 | if (net_ratelimit()) | |
233 | printk("arp_tables: error: '%s'\n", (char *)targinfo); | |
234 | ||
235 | return NF_DROP; | |
236 | } | |
237 | ||
238 | static inline struct arpt_entry *get_entry(void *base, unsigned int offset) | |
239 | { | |
240 | return (struct arpt_entry *)(base + offset); | |
241 | } | |
242 | ||
243 | unsigned int arpt_do_table(struct sk_buff **pskb, | |
244 | unsigned int hook, | |
245 | const struct net_device *in, | |
246 | const struct net_device *out, | |
247 | struct arpt_table *table, | |
248 | void *userdata) | |
249 | { | |
250 | static const char nulldevname[IFNAMSIZ]; | |
251 | unsigned int verdict = NF_DROP; | |
252 | struct arphdr *arp; | |
253 | int hotdrop = 0; | |
254 | struct arpt_entry *e, *back; | |
255 | const char *indev, *outdev; | |
256 | void *table_base; | |
257 | ||
258 | /* ARP header, plus 2 device addresses, plus 2 IP addresses. */ | |
259 | if (!pskb_may_pull((*pskb), (sizeof(struct arphdr) + | |
260 | (2 * (*pskb)->dev->addr_len) + | |
261 | (2 * sizeof(u32))))) | |
262 | return NF_DROP; | |
263 | ||
264 | indev = in ? in->name : nulldevname; | |
265 | outdev = out ? out->name : nulldevname; | |
266 | ||
267 | read_lock_bh(&table->lock); | |
31836064 | 268 | table_base = (void *)table->private->entries[smp_processor_id()]; |
1da177e4 LT |
269 | e = get_entry(table_base, table->private->hook_entry[hook]); |
270 | back = get_entry(table_base, table->private->underflow[hook]); | |
271 | ||
272 | arp = (*pskb)->nh.arph; | |
273 | do { | |
274 | if (arp_packet_match(arp, (*pskb)->dev, indev, outdev, &e->arp)) { | |
275 | struct arpt_entry_target *t; | |
276 | int hdr_len; | |
277 | ||
278 | hdr_len = sizeof(*arp) + (2 * sizeof(struct in_addr)) + | |
279 | (2 * (*pskb)->dev->addr_len); | |
280 | ADD_COUNTER(e->counters, hdr_len, 1); | |
281 | ||
282 | t = arpt_get_target(e); | |
283 | ||
284 | /* Standard target? */ | |
285 | if (!t->u.kernel.target->target) { | |
286 | int v; | |
287 | ||
288 | v = ((struct arpt_standard_target *)t)->verdict; | |
289 | if (v < 0) { | |
290 | /* Pop from stack? */ | |
291 | if (v != ARPT_RETURN) { | |
292 | verdict = (unsigned)(-v) - 1; | |
293 | break; | |
294 | } | |
295 | e = back; | |
296 | back = get_entry(table_base, | |
297 | back->comefrom); | |
298 | continue; | |
299 | } | |
300 | if (table_base + v | |
301 | != (void *)e + e->next_offset) { | |
302 | /* Save old back ptr in next entry */ | |
303 | struct arpt_entry *next | |
304 | = (void *)e + e->next_offset; | |
305 | next->comefrom = | |
306 | (void *)back - table_base; | |
307 | ||
308 | /* set back pointer to next entry */ | |
309 | back = next; | |
310 | } | |
311 | ||
312 | e = get_entry(table_base, v); | |
313 | } else { | |
314 | /* Targets which reenter must return | |
315 | * abs. verdicts | |
316 | */ | |
317 | verdict = t->u.kernel.target->target(pskb, | |
318 | hook, | |
319 | in, out, | |
320 | t->data, | |
321 | userdata); | |
322 | ||
323 | /* Target might have changed stuff. */ | |
324 | arp = (*pskb)->nh.arph; | |
325 | ||
326 | if (verdict == ARPT_CONTINUE) | |
327 | e = (void *)e + e->next_offset; | |
328 | else | |
329 | /* Verdict */ | |
330 | break; | |
331 | } | |
332 | } else { | |
333 | e = (void *)e + e->next_offset; | |
334 | } | |
335 | } while (!hotdrop); | |
336 | read_unlock_bh(&table->lock); | |
337 | ||
338 | if (hotdrop) | |
339 | return NF_DROP; | |
340 | else | |
341 | return verdict; | |
342 | } | |
343 | ||
6b7d31fc HW |
344 | /* |
345 | * These are weird, but module loading must not be done with mutex | |
346 | * held (since they will register), and we have to have a single | |
347 | * function to use try_then_request_module(). | |
348 | */ | |
349 | ||
350 | /* Find table by name, grabs mutex & ref. Returns ERR_PTR() on error. */ | |
351 | static inline struct arpt_table *find_table_lock(const char *name) | |
1da177e4 | 352 | { |
6b7d31fc | 353 | struct arpt_table *t; |
1da177e4 | 354 | |
6b7d31fc HW |
355 | if (down_interruptible(&arpt_mutex) != 0) |
356 | return ERR_PTR(-EINTR); | |
1da177e4 | 357 | |
6b7d31fc HW |
358 | list_for_each_entry(t, &arpt_tables, list) |
359 | if (strcmp(t->name, name) == 0 && try_module_get(t->me)) | |
360 | return t; | |
361 | up(&arpt_mutex); | |
362 | return NULL; | |
1da177e4 LT |
363 | } |
364 | ||
1da177e4 | 365 | |
6b7d31fc HW |
366 | /* Find target, grabs ref. Returns ERR_PTR() on error. */ |
367 | static inline struct arpt_target *find_target(const char *name, u8 revision) | |
368 | { | |
369 | struct arpt_target *t; | |
370 | int err = 0; | |
371 | ||
372 | if (down_interruptible(&arpt_mutex) != 0) | |
373 | return ERR_PTR(-EINTR); | |
374 | ||
375 | list_for_each_entry(t, &arpt_target, list) { | |
376 | if (strcmp(t->name, name) == 0) { | |
377 | if (t->revision == revision) { | |
378 | if (try_module_get(t->me)) { | |
379 | up(&arpt_mutex); | |
380 | return t; | |
381 | } | |
382 | } else | |
383 | err = -EPROTOTYPE; /* Found something. */ | |
384 | } | |
1da177e4 | 385 | } |
6b7d31fc HW |
386 | up(&arpt_mutex); |
387 | return ERR_PTR(err); | |
388 | } | |
1da177e4 | 389 | |
6b7d31fc HW |
390 | struct arpt_target *arpt_find_target(const char *name, u8 revision) |
391 | { | |
392 | struct arpt_target *target; | |
393 | ||
394 | target = try_then_request_module(find_target(name, revision), | |
395 | "arpt_%s", name); | |
396 | if (IS_ERR(target) || !target) | |
397 | return NULL; | |
398 | return target; | |
1da177e4 | 399 | } |
1da177e4 | 400 | |
6b7d31fc | 401 | static int target_revfn(const char *name, u8 revision, int *bestp) |
1da177e4 | 402 | { |
6b7d31fc HW |
403 | struct arpt_target *t; |
404 | int have_rev = 0; | |
405 | ||
406 | list_for_each_entry(t, &arpt_target, list) { | |
407 | if (strcmp(t->name, name) == 0) { | |
408 | if (t->revision > *bestp) | |
409 | *bestp = t->revision; | |
410 | if (t->revision == revision) | |
411 | have_rev =1; | |
412 | } | |
413 | } | |
414 | return have_rev; | |
1da177e4 LT |
415 | } |
416 | ||
6b7d31fc HW |
417 | /* Returns true or false (if no such extension at all) */ |
418 | static inline int find_revision(const char *name, u8 revision, | |
419 | int (*revfn)(const char *, u8, int *), | |
420 | int *err) | |
1da177e4 | 421 | { |
6b7d31fc HW |
422 | int have_rev, best = -1; |
423 | ||
424 | if (down_interruptible(&arpt_mutex) != 0) { | |
425 | *err = -EINTR; | |
426 | return 1; | |
427 | } | |
428 | have_rev = revfn(name, revision, &best); | |
429 | up(&arpt_mutex); | |
430 | ||
431 | /* Nothing at all? Return 0 to try loading module. */ | |
432 | if (best == -1) { | |
433 | *err = -ENOENT; | |
434 | return 0; | |
435 | } | |
436 | ||
437 | *err = best; | |
438 | if (!have_rev) | |
439 | *err = -EPROTONOSUPPORT; | |
440 | return 1; | |
1da177e4 LT |
441 | } |
442 | ||
6b7d31fc | 443 | |
1da177e4 LT |
444 | /* All zeroes == unconditional rule. */ |
445 | static inline int unconditional(const struct arpt_arp *arp) | |
446 | { | |
447 | unsigned int i; | |
448 | ||
449 | for (i = 0; i < sizeof(*arp)/sizeof(__u32); i++) | |
450 | if (((__u32 *)arp)[i]) | |
451 | return 0; | |
452 | ||
453 | return 1; | |
454 | } | |
455 | ||
456 | /* Figures out from what hook each rule can be called: returns 0 if | |
457 | * there are loops. Puts hook bitmask in comefrom. | |
458 | */ | |
31836064 ED |
459 | static int mark_source_chains(struct arpt_table_info *newinfo, |
460 | unsigned int valid_hooks, void *entry0) | |
1da177e4 LT |
461 | { |
462 | unsigned int hook; | |
463 | ||
464 | /* No recursion; use packet counter to save back ptrs (reset | |
465 | * to 0 as we leave), and comefrom to save source hook bitmask. | |
466 | */ | |
467 | for (hook = 0; hook < NF_ARP_NUMHOOKS; hook++) { | |
468 | unsigned int pos = newinfo->hook_entry[hook]; | |
469 | struct arpt_entry *e | |
31836064 | 470 | = (struct arpt_entry *)(entry0 + pos); |
1da177e4 LT |
471 | |
472 | if (!(valid_hooks & (1 << hook))) | |
473 | continue; | |
474 | ||
475 | /* Set initial back pointer. */ | |
476 | e->counters.pcnt = pos; | |
477 | ||
478 | for (;;) { | |
479 | struct arpt_standard_target *t | |
480 | = (void *)arpt_get_target(e); | |
481 | ||
482 | if (e->comefrom & (1 << NF_ARP_NUMHOOKS)) { | |
483 | printk("arptables: loop hook %u pos %u %08X.\n", | |
484 | hook, pos, e->comefrom); | |
485 | return 0; | |
486 | } | |
487 | e->comefrom | |
488 | |= ((1 << hook) | (1 << NF_ARP_NUMHOOKS)); | |
489 | ||
490 | /* Unconditional return/END. */ | |
491 | if (e->target_offset == sizeof(struct arpt_entry) | |
492 | && (strcmp(t->target.u.user.name, | |
493 | ARPT_STANDARD_TARGET) == 0) | |
494 | && t->verdict < 0 | |
495 | && unconditional(&e->arp)) { | |
496 | unsigned int oldpos, size; | |
497 | ||
498 | /* Return: backtrack through the last | |
499 | * big jump. | |
500 | */ | |
501 | do { | |
502 | e->comefrom ^= (1<<NF_ARP_NUMHOOKS); | |
503 | oldpos = pos; | |
504 | pos = e->counters.pcnt; | |
505 | e->counters.pcnt = 0; | |
506 | ||
507 | /* We're at the start. */ | |
508 | if (pos == oldpos) | |
509 | goto next; | |
510 | ||
511 | e = (struct arpt_entry *) | |
31836064 | 512 | (entry0 + pos); |
1da177e4 LT |
513 | } while (oldpos == pos + e->next_offset); |
514 | ||
515 | /* Move along one */ | |
516 | size = e->next_offset; | |
517 | e = (struct arpt_entry *) | |
31836064 | 518 | (entry0 + pos + size); |
1da177e4 LT |
519 | e->counters.pcnt = pos; |
520 | pos += size; | |
521 | } else { | |
522 | int newpos = t->verdict; | |
523 | ||
524 | if (strcmp(t->target.u.user.name, | |
525 | ARPT_STANDARD_TARGET) == 0 | |
526 | && newpos >= 0) { | |
527 | /* This a jump; chase it. */ | |
528 | duprintf("Jump rule %u -> %u\n", | |
529 | pos, newpos); | |
530 | } else { | |
531 | /* ... this is a fallthru */ | |
532 | newpos = pos + e->next_offset; | |
533 | } | |
534 | e = (struct arpt_entry *) | |
31836064 | 535 | (entry0 + newpos); |
1da177e4 LT |
536 | e->counters.pcnt = pos; |
537 | pos = newpos; | |
538 | } | |
539 | } | |
540 | next: | |
541 | duprintf("Finished chain %u\n", hook); | |
542 | } | |
543 | return 1; | |
544 | } | |
545 | ||
546 | static inline int standard_check(const struct arpt_entry_target *t, | |
547 | unsigned int max_offset) | |
548 | { | |
549 | struct arpt_standard_target *targ = (void *)t; | |
550 | ||
551 | /* Check standard info. */ | |
552 | if (t->u.target_size | |
553 | != ARPT_ALIGN(sizeof(struct arpt_standard_target))) { | |
554 | duprintf("arpt_standard_check: target size %u != %Zu\n", | |
555 | t->u.target_size, | |
556 | ARPT_ALIGN(sizeof(struct arpt_standard_target))); | |
557 | return 0; | |
558 | } | |
559 | ||
560 | if (targ->verdict >= 0 | |
561 | && targ->verdict > max_offset - sizeof(struct arpt_entry)) { | |
562 | duprintf("arpt_standard_check: bad verdict (%i)\n", | |
563 | targ->verdict); | |
564 | return 0; | |
565 | } | |
566 | ||
567 | if (targ->verdict < -NF_MAX_VERDICT - 1) { | |
568 | duprintf("arpt_standard_check: bad negative verdict (%i)\n", | |
569 | targ->verdict); | |
570 | return 0; | |
571 | } | |
572 | return 1; | |
573 | } | |
574 | ||
575 | static struct arpt_target arpt_standard_target; | |
576 | ||
577 | static inline int check_entry(struct arpt_entry *e, const char *name, unsigned int size, | |
578 | unsigned int *i) | |
579 | { | |
580 | struct arpt_entry_target *t; | |
581 | struct arpt_target *target; | |
582 | int ret; | |
583 | ||
584 | if (!arp_checkentry(&e->arp)) { | |
585 | duprintf("arp_tables: arp check failed %p %s.\n", e, name); | |
586 | return -EINVAL; | |
587 | } | |
588 | ||
589 | t = arpt_get_target(e); | |
6b7d31fc HW |
590 | target = try_then_request_module(find_target(t->u.user.name, |
591 | t->u.user.revision), | |
592 | "arpt_%s", t->u.user.name); | |
593 | if (IS_ERR(target) || !target) { | |
1da177e4 | 594 | duprintf("check_entry: `%s' not found\n", t->u.user.name); |
6b7d31fc | 595 | ret = target ? PTR_ERR(target) : -ENOENT; |
1da177e4 LT |
596 | goto out; |
597 | } | |
1da177e4 | 598 | t->u.kernel.target = target; |
1da177e4 LT |
599 | |
600 | if (t->u.kernel.target == &arpt_standard_target) { | |
601 | if (!standard_check(t, size)) { | |
602 | ret = -EINVAL; | |
603 | goto out; | |
604 | } | |
605 | } else if (t->u.kernel.target->checkentry | |
606 | && !t->u.kernel.target->checkentry(name, e, t->data, | |
607 | t->u.target_size | |
608 | - sizeof(*t), | |
609 | e->comefrom)) { | |
610 | module_put(t->u.kernel.target->me); | |
611 | duprintf("arp_tables: check failed for `%s'.\n", | |
612 | t->u.kernel.target->name); | |
613 | ret = -EINVAL; | |
614 | goto out; | |
615 | } | |
616 | ||
617 | (*i)++; | |
618 | return 0; | |
619 | ||
1da177e4 LT |
620 | out: |
621 | return ret; | |
622 | } | |
623 | ||
624 | static inline int check_entry_size_and_hooks(struct arpt_entry *e, | |
625 | struct arpt_table_info *newinfo, | |
626 | unsigned char *base, | |
627 | unsigned char *limit, | |
628 | const unsigned int *hook_entries, | |
629 | const unsigned int *underflows, | |
630 | unsigned int *i) | |
631 | { | |
632 | unsigned int h; | |
633 | ||
634 | if ((unsigned long)e % __alignof__(struct arpt_entry) != 0 | |
635 | || (unsigned char *)e + sizeof(struct arpt_entry) >= limit) { | |
636 | duprintf("Bad offset %p\n", e); | |
637 | return -EINVAL; | |
638 | } | |
639 | ||
640 | if (e->next_offset | |
641 | < sizeof(struct arpt_entry) + sizeof(struct arpt_entry_target)) { | |
642 | duprintf("checking: element %p size %u\n", | |
643 | e, e->next_offset); | |
644 | return -EINVAL; | |
645 | } | |
646 | ||
647 | /* Check hooks & underflows */ | |
648 | for (h = 0; h < NF_ARP_NUMHOOKS; h++) { | |
649 | if ((unsigned char *)e - base == hook_entries[h]) | |
650 | newinfo->hook_entry[h] = hook_entries[h]; | |
651 | if ((unsigned char *)e - base == underflows[h]) | |
652 | newinfo->underflow[h] = underflows[h]; | |
653 | } | |
654 | ||
655 | /* FIXME: underflows must be unconditional, standard verdicts | |
656 | < 0 (not ARPT_RETURN). --RR */ | |
657 | ||
658 | /* Clear counters and comefrom */ | |
659 | e->counters = ((struct arpt_counters) { 0, 0 }); | |
660 | e->comefrom = 0; | |
661 | ||
662 | (*i)++; | |
663 | return 0; | |
664 | } | |
665 | ||
666 | static inline int cleanup_entry(struct arpt_entry *e, unsigned int *i) | |
667 | { | |
668 | struct arpt_entry_target *t; | |
669 | ||
670 | if (i && (*i)-- == 0) | |
671 | return 1; | |
672 | ||
673 | t = arpt_get_target(e); | |
674 | if (t->u.kernel.target->destroy) | |
675 | t->u.kernel.target->destroy(t->data, | |
676 | t->u.target_size - sizeof(*t)); | |
677 | module_put(t->u.kernel.target->me); | |
678 | return 0; | |
679 | } | |
680 | ||
681 | /* Checks and translates the user-supplied table segment (held in | |
682 | * newinfo). | |
683 | */ | |
684 | static int translate_table(const char *name, | |
685 | unsigned int valid_hooks, | |
686 | struct arpt_table_info *newinfo, | |
31836064 | 687 | void *entry0, |
1da177e4 LT |
688 | unsigned int size, |
689 | unsigned int number, | |
690 | const unsigned int *hook_entries, | |
691 | const unsigned int *underflows) | |
692 | { | |
693 | unsigned int i; | |
694 | int ret; | |
695 | ||
696 | newinfo->size = size; | |
697 | newinfo->number = number; | |
698 | ||
699 | /* Init all hooks to impossible value. */ | |
700 | for (i = 0; i < NF_ARP_NUMHOOKS; i++) { | |
701 | newinfo->hook_entry[i] = 0xFFFFFFFF; | |
702 | newinfo->underflow[i] = 0xFFFFFFFF; | |
703 | } | |
704 | ||
705 | duprintf("translate_table: size %u\n", newinfo->size); | |
706 | i = 0; | |
707 | ||
708 | /* Walk through entries, checking offsets. */ | |
31836064 | 709 | ret = ARPT_ENTRY_ITERATE(entry0, newinfo->size, |
1da177e4 LT |
710 | check_entry_size_and_hooks, |
711 | newinfo, | |
31836064 ED |
712 | entry0, |
713 | entry0 + size, | |
1da177e4 LT |
714 | hook_entries, underflows, &i); |
715 | duprintf("translate_table: ARPT_ENTRY_ITERATE gives %d\n", ret); | |
716 | if (ret != 0) | |
717 | return ret; | |
718 | ||
719 | if (i != number) { | |
720 | duprintf("translate_table: %u not %u entries\n", | |
721 | i, number); | |
722 | return -EINVAL; | |
723 | } | |
724 | ||
725 | /* Check hooks all assigned */ | |
726 | for (i = 0; i < NF_ARP_NUMHOOKS; i++) { | |
727 | /* Only hooks which are valid */ | |
728 | if (!(valid_hooks & (1 << i))) | |
729 | continue; | |
730 | if (newinfo->hook_entry[i] == 0xFFFFFFFF) { | |
731 | duprintf("Invalid hook entry %u %u\n", | |
732 | i, hook_entries[i]); | |
733 | return -EINVAL; | |
734 | } | |
735 | if (newinfo->underflow[i] == 0xFFFFFFFF) { | |
736 | duprintf("Invalid underflow %u %u\n", | |
737 | i, underflows[i]); | |
738 | return -EINVAL; | |
739 | } | |
740 | } | |
741 | ||
31836064 | 742 | if (!mark_source_chains(newinfo, valid_hooks, entry0)) { |
1da177e4 LT |
743 | duprintf("Looping hook\n"); |
744 | return -ELOOP; | |
745 | } | |
746 | ||
747 | /* Finally, each sanity check must pass */ | |
748 | i = 0; | |
31836064 | 749 | ret = ARPT_ENTRY_ITERATE(entry0, newinfo->size, |
1da177e4 LT |
750 | check_entry, name, size, &i); |
751 | ||
752 | if (ret != 0) { | |
31836064 | 753 | ARPT_ENTRY_ITERATE(entry0, newinfo->size, |
1da177e4 LT |
754 | cleanup_entry, &i); |
755 | return ret; | |
756 | } | |
757 | ||
758 | /* And one copy for every other CPU */ | |
c8923c6b | 759 | for_each_cpu(i) { |
31836064 ED |
760 | if (newinfo->entries[i] && newinfo->entries[i] != entry0) |
761 | memcpy(newinfo->entries[i], entry0, newinfo->size); | |
1da177e4 LT |
762 | } |
763 | ||
764 | return ret; | |
765 | } | |
766 | ||
767 | static struct arpt_table_info *replace_table(struct arpt_table *table, | |
768 | unsigned int num_counters, | |
769 | struct arpt_table_info *newinfo, | |
770 | int *error) | |
771 | { | |
772 | struct arpt_table_info *oldinfo; | |
773 | ||
774 | /* Do the substitution. */ | |
775 | write_lock_bh(&table->lock); | |
776 | /* Check inside lock: is the old number correct? */ | |
777 | if (num_counters != table->private->number) { | |
778 | duprintf("num_counters != table->private->number (%u/%u)\n", | |
779 | num_counters, table->private->number); | |
780 | write_unlock_bh(&table->lock); | |
781 | *error = -EAGAIN; | |
782 | return NULL; | |
783 | } | |
784 | oldinfo = table->private; | |
785 | table->private = newinfo; | |
786 | newinfo->initial_entries = oldinfo->initial_entries; | |
787 | write_unlock_bh(&table->lock); | |
788 | ||
789 | return oldinfo; | |
790 | } | |
791 | ||
792 | /* Gets counters. */ | |
793 | static inline int add_entry_to_counter(const struct arpt_entry *e, | |
794 | struct arpt_counters total[], | |
795 | unsigned int *i) | |
796 | { | |
797 | ADD_COUNTER(total[*i], e->counters.bcnt, e->counters.pcnt); | |
798 | ||
799 | (*i)++; | |
800 | return 0; | |
801 | } | |
802 | ||
31836064 ED |
803 | static inline int set_entry_to_counter(const struct arpt_entry *e, |
804 | struct arpt_counters total[], | |
805 | unsigned int *i) | |
806 | { | |
807 | SET_COUNTER(total[*i], e->counters.bcnt, e->counters.pcnt); | |
808 | ||
809 | (*i)++; | |
810 | return 0; | |
811 | } | |
812 | ||
1da177e4 LT |
813 | static void get_counters(const struct arpt_table_info *t, |
814 | struct arpt_counters counters[]) | |
815 | { | |
816 | unsigned int cpu; | |
817 | unsigned int i; | |
31836064 ED |
818 | unsigned int curcpu; |
819 | ||
820 | /* Instead of clearing (by a previous call to memset()) | |
821 | * the counters and using adds, we set the counters | |
822 | * with data used by 'current' CPU | |
823 | * We dont care about preemption here. | |
824 | */ | |
825 | curcpu = raw_smp_processor_id(); | |
826 | ||
827 | i = 0; | |
828 | ARPT_ENTRY_ITERATE(t->entries[curcpu], | |
829 | t->size, | |
830 | set_entry_to_counter, | |
831 | counters, | |
832 | &i); | |
1da177e4 | 833 | |
c8923c6b | 834 | for_each_cpu(cpu) { |
31836064 ED |
835 | if (cpu == curcpu) |
836 | continue; | |
1da177e4 | 837 | i = 0; |
31836064 | 838 | ARPT_ENTRY_ITERATE(t->entries[cpu], |
1da177e4 LT |
839 | t->size, |
840 | add_entry_to_counter, | |
841 | counters, | |
842 | &i); | |
843 | } | |
844 | } | |
845 | ||
846 | static int copy_entries_to_user(unsigned int total_size, | |
847 | struct arpt_table *table, | |
848 | void __user *userptr) | |
849 | { | |
850 | unsigned int off, num, countersize; | |
851 | struct arpt_entry *e; | |
852 | struct arpt_counters *counters; | |
853 | int ret = 0; | |
31836064 | 854 | void *loc_cpu_entry; |
1da177e4 LT |
855 | |
856 | /* We need atomic snapshot of counters: rest doesn't change | |
857 | * (other than comefrom, which userspace doesn't care | |
858 | * about). | |
859 | */ | |
860 | countersize = sizeof(struct arpt_counters) * table->private->number; | |
861 | counters = vmalloc(countersize); | |
862 | ||
863 | if (counters == NULL) | |
864 | return -ENOMEM; | |
865 | ||
866 | /* First, sum counters... */ | |
1da177e4 LT |
867 | write_lock_bh(&table->lock); |
868 | get_counters(table->private, counters); | |
869 | write_unlock_bh(&table->lock); | |
870 | ||
31836064 ED |
871 | loc_cpu_entry = table->private->entries[raw_smp_processor_id()]; |
872 | /* ... then copy entire thing ... */ | |
873 | if (copy_to_user(userptr, loc_cpu_entry, total_size) != 0) { | |
1da177e4 LT |
874 | ret = -EFAULT; |
875 | goto free_counters; | |
876 | } | |
877 | ||
878 | /* FIXME: use iterator macros --RR */ | |
879 | /* ... then go back and fix counters and names */ | |
880 | for (off = 0, num = 0; off < total_size; off += e->next_offset, num++){ | |
881 | struct arpt_entry_target *t; | |
882 | ||
31836064 | 883 | e = (struct arpt_entry *)(loc_cpu_entry + off); |
1da177e4 LT |
884 | if (copy_to_user(userptr + off |
885 | + offsetof(struct arpt_entry, counters), | |
886 | &counters[num], | |
887 | sizeof(counters[num])) != 0) { | |
888 | ret = -EFAULT; | |
889 | goto free_counters; | |
890 | } | |
891 | ||
892 | t = arpt_get_target(e); | |
893 | if (copy_to_user(userptr + off + e->target_offset | |
894 | + offsetof(struct arpt_entry_target, | |
895 | u.user.name), | |
896 | t->u.kernel.target->name, | |
897 | strlen(t->u.kernel.target->name)+1) != 0) { | |
898 | ret = -EFAULT; | |
899 | goto free_counters; | |
900 | } | |
901 | } | |
902 | ||
903 | free_counters: | |
904 | vfree(counters); | |
905 | return ret; | |
906 | } | |
907 | ||
908 | static int get_entries(const struct arpt_get_entries *entries, | |
909 | struct arpt_get_entries __user *uptr) | |
910 | { | |
911 | int ret; | |
912 | struct arpt_table *t; | |
913 | ||
6b7d31fc HW |
914 | t = find_table_lock(entries->name); |
915 | if (t || !IS_ERR(t)) { | |
1da177e4 LT |
916 | duprintf("t->private->number = %u\n", |
917 | t->private->number); | |
918 | if (entries->size == t->private->size) | |
919 | ret = copy_entries_to_user(t->private->size, | |
920 | t, uptr->entrytable); | |
921 | else { | |
922 | duprintf("get_entries: I've got %u not %u!\n", | |
923 | t->private->size, | |
924 | entries->size); | |
925 | ret = -EINVAL; | |
926 | } | |
6b7d31fc | 927 | module_put(t->me); |
1da177e4 LT |
928 | up(&arpt_mutex); |
929 | } else | |
6b7d31fc | 930 | ret = t ? PTR_ERR(t) : -ENOENT; |
1da177e4 LT |
931 | |
932 | return ret; | |
933 | } | |
934 | ||
31836064 ED |
935 | static void free_table_info(struct arpt_table_info *info) |
936 | { | |
937 | int cpu; | |
938 | for_each_cpu(cpu) { | |
939 | if (info->size <= PAGE_SIZE) | |
940 | kfree(info->entries[cpu]); | |
941 | else | |
942 | vfree(info->entries[cpu]); | |
943 | } | |
944 | kfree(info); | |
945 | } | |
946 | ||
947 | static struct arpt_table_info *alloc_table_info(unsigned int size) | |
948 | { | |
949 | struct arpt_table_info *newinfo; | |
950 | int cpu; | |
951 | ||
952 | newinfo = kzalloc(sizeof(struct arpt_table_info), GFP_KERNEL); | |
953 | if (!newinfo) | |
954 | return NULL; | |
955 | ||
956 | newinfo->size = size; | |
957 | ||
958 | for_each_cpu(cpu) { | |
959 | if (size <= PAGE_SIZE) | |
960 | newinfo->entries[cpu] = kmalloc_node(size, | |
961 | GFP_KERNEL, | |
962 | cpu_to_node(cpu)); | |
963 | else | |
964 | newinfo->entries[cpu] = vmalloc_node(size, | |
965 | cpu_to_node(cpu)); | |
966 | ||
967 | if (newinfo->entries[cpu] == NULL) { | |
968 | free_table_info(newinfo); | |
969 | return NULL; | |
970 | } | |
971 | } | |
972 | ||
973 | return newinfo; | |
974 | } | |
975 | ||
1da177e4 LT |
976 | static int do_replace(void __user *user, unsigned int len) |
977 | { | |
978 | int ret; | |
979 | struct arpt_replace tmp; | |
980 | struct arpt_table *t; | |
981 | struct arpt_table_info *newinfo, *oldinfo; | |
982 | struct arpt_counters *counters; | |
31836064 | 983 | void *loc_cpu_entry, *loc_cpu_old_entry; |
1da177e4 LT |
984 | |
985 | if (copy_from_user(&tmp, user, sizeof(tmp)) != 0) | |
986 | return -EFAULT; | |
987 | ||
988 | /* Hack: Causes ipchains to give correct error msg --RR */ | |
989 | if (len != sizeof(tmp) + tmp.size) | |
990 | return -ENOPROTOOPT; | |
991 | ||
992 | /* Pedantry: prevent them from hitting BUG() in vmalloc.c --RR */ | |
993 | if ((SMP_ALIGN(tmp.size) >> PAGE_SHIFT) + 2 > num_physpages) | |
994 | return -ENOMEM; | |
995 | ||
31836064 | 996 | newinfo = alloc_table_info(tmp.size); |
1da177e4 LT |
997 | if (!newinfo) |
998 | return -ENOMEM; | |
999 | ||
31836064 ED |
1000 | /* choose the copy that is on our node/cpu */ |
1001 | loc_cpu_entry = newinfo->entries[raw_smp_processor_id()]; | |
1002 | if (copy_from_user(loc_cpu_entry, user + sizeof(tmp), | |
1da177e4 LT |
1003 | tmp.size) != 0) { |
1004 | ret = -EFAULT; | |
1005 | goto free_newinfo; | |
1006 | } | |
1007 | ||
1008 | counters = vmalloc(tmp.num_counters * sizeof(struct arpt_counters)); | |
1009 | if (!counters) { | |
1010 | ret = -ENOMEM; | |
1011 | goto free_newinfo; | |
1012 | } | |
1da177e4 LT |
1013 | |
1014 | ret = translate_table(tmp.name, tmp.valid_hooks, | |
31836064 | 1015 | newinfo, loc_cpu_entry, tmp.size, tmp.num_entries, |
1da177e4 LT |
1016 | tmp.hook_entry, tmp.underflow); |
1017 | if (ret != 0) | |
1018 | goto free_newinfo_counters; | |
1019 | ||
1020 | duprintf("arp_tables: Translated table\n"); | |
1021 | ||
6b7d31fc HW |
1022 | t = try_then_request_module(find_table_lock(tmp.name), |
1023 | "arptable_%s", tmp.name); | |
1024 | if (!t || IS_ERR(t)) { | |
1025 | ret = t ? PTR_ERR(t) : -ENOENT; | |
1da177e4 | 1026 | goto free_newinfo_counters_untrans; |
6b7d31fc | 1027 | } |
1da177e4 LT |
1028 | |
1029 | /* You lied! */ | |
1030 | if (tmp.valid_hooks != t->valid_hooks) { | |
1031 | duprintf("Valid hook crap: %08X vs %08X\n", | |
1032 | tmp.valid_hooks, t->valid_hooks); | |
1033 | ret = -EINVAL; | |
6b7d31fc | 1034 | goto put_module; |
1da177e4 LT |
1035 | } |
1036 | ||
1037 | oldinfo = replace_table(t, tmp.num_counters, newinfo, &ret); | |
1038 | if (!oldinfo) | |
1039 | goto put_module; | |
1040 | ||
1041 | /* Update module usage count based on number of rules */ | |
1042 | duprintf("do_replace: oldnum=%u, initnum=%u, newnum=%u\n", | |
1043 | oldinfo->number, oldinfo->initial_entries, newinfo->number); | |
1044 | if ((oldinfo->number > oldinfo->initial_entries) || | |
1045 | (newinfo->number <= oldinfo->initial_entries)) | |
1046 | module_put(t->me); | |
1047 | if ((oldinfo->number > oldinfo->initial_entries) && | |
1048 | (newinfo->number <= oldinfo->initial_entries)) | |
1049 | module_put(t->me); | |
1050 | ||
1051 | /* Get the old counters. */ | |
1052 | get_counters(oldinfo, counters); | |
1053 | /* Decrease module usage counts and free resource */ | |
31836064 ED |
1054 | loc_cpu_old_entry = oldinfo->entries[raw_smp_processor_id()]; |
1055 | ARPT_ENTRY_ITERATE(loc_cpu_old_entry, oldinfo->size, cleanup_entry,NULL); | |
1056 | ||
1057 | free_table_info(oldinfo); | |
1da177e4 LT |
1058 | if (copy_to_user(tmp.counters, counters, |
1059 | sizeof(struct arpt_counters) * tmp.num_counters) != 0) | |
1060 | ret = -EFAULT; | |
1061 | vfree(counters); | |
1062 | up(&arpt_mutex); | |
1063 | return ret; | |
1064 | ||
1065 | put_module: | |
1066 | module_put(t->me); | |
1da177e4 LT |
1067 | up(&arpt_mutex); |
1068 | free_newinfo_counters_untrans: | |
31836064 | 1069 | ARPT_ENTRY_ITERATE(loc_cpu_entry, newinfo->size, cleanup_entry, NULL); |
1da177e4 LT |
1070 | free_newinfo_counters: |
1071 | vfree(counters); | |
1072 | free_newinfo: | |
31836064 | 1073 | free_table_info(newinfo); |
1da177e4 LT |
1074 | return ret; |
1075 | } | |
1076 | ||
1077 | /* We're lazy, and add to the first CPU; overflow works its fey magic | |
1078 | * and everything is OK. | |
1079 | */ | |
1080 | static inline int add_counter_to_entry(struct arpt_entry *e, | |
1081 | const struct arpt_counters addme[], | |
1082 | unsigned int *i) | |
1083 | { | |
1084 | ||
1085 | ADD_COUNTER(e->counters, addme[*i].bcnt, addme[*i].pcnt); | |
1086 | ||
1087 | (*i)++; | |
1088 | return 0; | |
1089 | } | |
1090 | ||
1091 | static int do_add_counters(void __user *user, unsigned int len) | |
1092 | { | |
1093 | unsigned int i; | |
1094 | struct arpt_counters_info tmp, *paddc; | |
1095 | struct arpt_table *t; | |
6b7d31fc | 1096 | int ret = 0; |
31836064 | 1097 | void *loc_cpu_entry; |
1da177e4 LT |
1098 | |
1099 | if (copy_from_user(&tmp, user, sizeof(tmp)) != 0) | |
1100 | return -EFAULT; | |
1101 | ||
1102 | if (len != sizeof(tmp) + tmp.num_counters*sizeof(struct arpt_counters)) | |
1103 | return -EINVAL; | |
1104 | ||
1105 | paddc = vmalloc(len); | |
1106 | if (!paddc) | |
1107 | return -ENOMEM; | |
1108 | ||
1109 | if (copy_from_user(paddc, user, len) != 0) { | |
1110 | ret = -EFAULT; | |
1111 | goto free; | |
1112 | } | |
1113 | ||
6b7d31fc HW |
1114 | t = find_table_lock(tmp.name); |
1115 | if (!t || IS_ERR(t)) { | |
1116 | ret = t ? PTR_ERR(t) : -ENOENT; | |
1da177e4 | 1117 | goto free; |
6b7d31fc | 1118 | } |
1da177e4 LT |
1119 | |
1120 | write_lock_bh(&t->lock); | |
1121 | if (t->private->number != paddc->num_counters) { | |
1122 | ret = -EINVAL; | |
1123 | goto unlock_up_free; | |
1124 | } | |
1125 | ||
1126 | i = 0; | |
31836064 ED |
1127 | /* Choose the copy that is on our node */ |
1128 | loc_cpu_entry = t->private->entries[smp_processor_id()]; | |
1129 | ARPT_ENTRY_ITERATE(loc_cpu_entry, | |
1da177e4 LT |
1130 | t->private->size, |
1131 | add_counter_to_entry, | |
1132 | paddc->counters, | |
1133 | &i); | |
1134 | unlock_up_free: | |
1135 | write_unlock_bh(&t->lock); | |
1136 | up(&arpt_mutex); | |
6b7d31fc | 1137 | module_put(t->me); |
1da177e4 LT |
1138 | free: |
1139 | vfree(paddc); | |
1140 | ||
1141 | return ret; | |
1142 | } | |
1143 | ||
1144 | static int do_arpt_set_ctl(struct sock *sk, int cmd, void __user *user, unsigned int len) | |
1145 | { | |
1146 | int ret; | |
1147 | ||
1148 | if (!capable(CAP_NET_ADMIN)) | |
1149 | return -EPERM; | |
1150 | ||
1151 | switch (cmd) { | |
1152 | case ARPT_SO_SET_REPLACE: | |
1153 | ret = do_replace(user, len); | |
1154 | break; | |
1155 | ||
1156 | case ARPT_SO_SET_ADD_COUNTERS: | |
1157 | ret = do_add_counters(user, len); | |
1158 | break; | |
1159 | ||
1160 | default: | |
1161 | duprintf("do_arpt_set_ctl: unknown request %i\n", cmd); | |
1162 | ret = -EINVAL; | |
1163 | } | |
1164 | ||
1165 | return ret; | |
1166 | } | |
1167 | ||
1168 | static int do_arpt_get_ctl(struct sock *sk, int cmd, void __user *user, int *len) | |
1169 | { | |
1170 | int ret; | |
1171 | ||
1172 | if (!capable(CAP_NET_ADMIN)) | |
1173 | return -EPERM; | |
1174 | ||
1175 | switch (cmd) { | |
1176 | case ARPT_SO_GET_INFO: { | |
1177 | char name[ARPT_TABLE_MAXNAMELEN]; | |
1178 | struct arpt_table *t; | |
1179 | ||
1180 | if (*len != sizeof(struct arpt_getinfo)) { | |
1181 | duprintf("length %u != %Zu\n", *len, | |
1182 | sizeof(struct arpt_getinfo)); | |
1183 | ret = -EINVAL; | |
1184 | break; | |
1185 | } | |
1186 | ||
1187 | if (copy_from_user(name, user, sizeof(name)) != 0) { | |
1188 | ret = -EFAULT; | |
1189 | break; | |
1190 | } | |
1191 | name[ARPT_TABLE_MAXNAMELEN-1] = '\0'; | |
6b7d31fc HW |
1192 | |
1193 | t = try_then_request_module(find_table_lock(name), | |
1194 | "arptable_%s", name); | |
1195 | if (t && !IS_ERR(t)) { | |
1da177e4 LT |
1196 | struct arpt_getinfo info; |
1197 | ||
1198 | info.valid_hooks = t->valid_hooks; | |
1199 | memcpy(info.hook_entry, t->private->hook_entry, | |
1200 | sizeof(info.hook_entry)); | |
1201 | memcpy(info.underflow, t->private->underflow, | |
1202 | sizeof(info.underflow)); | |
1203 | info.num_entries = t->private->number; | |
1204 | info.size = t->private->size; | |
1205 | strcpy(info.name, name); | |
1206 | ||
1207 | if (copy_to_user(user, &info, *len) != 0) | |
1208 | ret = -EFAULT; | |
1209 | else | |
1210 | ret = 0; | |
1da177e4 | 1211 | up(&arpt_mutex); |
6b7d31fc HW |
1212 | module_put(t->me); |
1213 | } else | |
1214 | ret = t ? PTR_ERR(t) : -ENOENT; | |
1da177e4 LT |
1215 | } |
1216 | break; | |
1217 | ||
1218 | case ARPT_SO_GET_ENTRIES: { | |
1219 | struct arpt_get_entries get; | |
1220 | ||
1221 | if (*len < sizeof(get)) { | |
1222 | duprintf("get_entries: %u < %Zu\n", *len, sizeof(get)); | |
1223 | ret = -EINVAL; | |
1224 | } else if (copy_from_user(&get, user, sizeof(get)) != 0) { | |
1225 | ret = -EFAULT; | |
1226 | } else if (*len != sizeof(struct arpt_get_entries) + get.size) { | |
1227 | duprintf("get_entries: %u != %Zu\n", *len, | |
1228 | sizeof(struct arpt_get_entries) + get.size); | |
1229 | ret = -EINVAL; | |
1230 | } else | |
1231 | ret = get_entries(&get, user); | |
1232 | break; | |
1233 | } | |
1234 | ||
6b7d31fc HW |
1235 | case ARPT_SO_GET_REVISION_TARGET: { |
1236 | struct arpt_get_revision rev; | |
1237 | ||
1238 | if (*len != sizeof(rev)) { | |
1239 | ret = -EINVAL; | |
1240 | break; | |
1241 | } | |
1242 | if (copy_from_user(&rev, user, sizeof(rev)) != 0) { | |
1243 | ret = -EFAULT; | |
1244 | break; | |
1245 | } | |
1246 | ||
1247 | try_then_request_module(find_revision(rev.name, rev.revision, | |
1248 | target_revfn, &ret), | |
1249 | "arpt_%s", rev.name); | |
1250 | break; | |
1251 | } | |
1252 | ||
1da177e4 LT |
1253 | default: |
1254 | duprintf("do_arpt_get_ctl: unknown request %i\n", cmd); | |
1255 | ret = -EINVAL; | |
1256 | } | |
1257 | ||
1258 | return ret; | |
1259 | } | |
1260 | ||
1261 | /* Registration hooks for targets. */ | |
1262 | int arpt_register_target(struct arpt_target *target) | |
1263 | { | |
1264 | int ret; | |
1265 | ||
1266 | ret = down_interruptible(&arpt_mutex); | |
1267 | if (ret != 0) | |
1268 | return ret; | |
1269 | ||
6b7d31fc | 1270 | list_add(&target->list, &arpt_target); |
1da177e4 | 1271 | up(&arpt_mutex); |
6b7d31fc | 1272 | |
1da177e4 LT |
1273 | return ret; |
1274 | } | |
1275 | ||
1276 | void arpt_unregister_target(struct arpt_target *target) | |
1277 | { | |
1278 | down(&arpt_mutex); | |
1279 | LIST_DELETE(&arpt_target, target); | |
1280 | up(&arpt_mutex); | |
1281 | } | |
1282 | ||
1283 | int arpt_register_table(struct arpt_table *table, | |
1284 | const struct arpt_replace *repl) | |
1285 | { | |
1286 | int ret; | |
1287 | struct arpt_table_info *newinfo; | |
1288 | static struct arpt_table_info bootstrap | |
1289 | = { 0, 0, 0, { 0 }, { 0 }, { } }; | |
31836064 | 1290 | void *loc_cpu_entry; |
1da177e4 | 1291 | |
31836064 | 1292 | newinfo = alloc_table_info(repl->size); |
1da177e4 LT |
1293 | if (!newinfo) { |
1294 | ret = -ENOMEM; | |
1295 | return ret; | |
1296 | } | |
31836064 ED |
1297 | |
1298 | /* choose the copy on our node/cpu */ | |
1299 | loc_cpu_entry = newinfo->entries[raw_smp_processor_id()]; | |
1300 | memcpy(loc_cpu_entry, repl->entries, repl->size); | |
1da177e4 LT |
1301 | |
1302 | ret = translate_table(table->name, table->valid_hooks, | |
31836064 | 1303 | newinfo, loc_cpu_entry, repl->size, |
1da177e4 LT |
1304 | repl->num_entries, |
1305 | repl->hook_entry, | |
1306 | repl->underflow); | |
1307 | duprintf("arpt_register_table: translate table gives %d\n", ret); | |
1308 | if (ret != 0) { | |
31836064 | 1309 | free_table_info(newinfo); |
1da177e4 LT |
1310 | return ret; |
1311 | } | |
1312 | ||
1313 | ret = down_interruptible(&arpt_mutex); | |
1314 | if (ret != 0) { | |
31836064 | 1315 | free_table_info(newinfo); |
1da177e4 LT |
1316 | return ret; |
1317 | } | |
1318 | ||
1319 | /* Don't autoload: we'd eat our tail... */ | |
1320 | if (list_named_find(&arpt_tables, table->name)) { | |
1321 | ret = -EEXIST; | |
1322 | goto free_unlock; | |
1323 | } | |
1324 | ||
1325 | /* Simplifies replace_table code. */ | |
1326 | table->private = &bootstrap; | |
1327 | if (!replace_table(table, 0, newinfo, &ret)) | |
1328 | goto free_unlock; | |
1329 | ||
1330 | duprintf("table->private->number = %u\n", | |
1331 | table->private->number); | |
1332 | ||
1333 | /* save number of initial entries */ | |
1334 | table->private->initial_entries = table->private->number; | |
1335 | ||
1336 | rwlock_init(&table->lock); | |
1337 | list_prepend(&arpt_tables, table); | |
1338 | ||
1339 | unlock: | |
1340 | up(&arpt_mutex); | |
1341 | return ret; | |
1342 | ||
1343 | free_unlock: | |
31836064 | 1344 | free_table_info(newinfo); |
1da177e4 LT |
1345 | goto unlock; |
1346 | } | |
1347 | ||
1348 | void arpt_unregister_table(struct arpt_table *table) | |
1349 | { | |
31836064 ED |
1350 | void *loc_cpu_entry; |
1351 | ||
1da177e4 LT |
1352 | down(&arpt_mutex); |
1353 | LIST_DELETE(&arpt_tables, table); | |
1354 | up(&arpt_mutex); | |
1355 | ||
1356 | /* Decrease module usage counts and free resources */ | |
31836064 ED |
1357 | loc_cpu_entry = table->private->entries[raw_smp_processor_id()]; |
1358 | ARPT_ENTRY_ITERATE(loc_cpu_entry, table->private->size, | |
1da177e4 | 1359 | cleanup_entry, NULL); |
31836064 | 1360 | free_table_info(table->private); |
1da177e4 LT |
1361 | } |
1362 | ||
1363 | /* The built-in targets: standard (NULL) and error. */ | |
1364 | static struct arpt_target arpt_standard_target = { | |
1365 | .name = ARPT_STANDARD_TARGET, | |
1366 | }; | |
1367 | ||
1368 | static struct arpt_target arpt_error_target = { | |
1369 | .name = ARPT_ERROR_TARGET, | |
1370 | .target = arpt_error, | |
1371 | }; | |
1372 | ||
1373 | static struct nf_sockopt_ops arpt_sockopts = { | |
1374 | .pf = PF_INET, | |
1375 | .set_optmin = ARPT_BASE_CTL, | |
1376 | .set_optmax = ARPT_SO_SET_MAX+1, | |
1377 | .set = do_arpt_set_ctl, | |
1378 | .get_optmin = ARPT_BASE_CTL, | |
1379 | .get_optmax = ARPT_SO_GET_MAX+1, | |
1380 | .get = do_arpt_get_ctl, | |
1381 | }; | |
1382 | ||
1383 | #ifdef CONFIG_PROC_FS | |
1384 | static inline int print_name(const struct arpt_table *t, | |
1385 | off_t start_offset, char *buffer, int length, | |
1386 | off_t *pos, unsigned int *count) | |
1387 | { | |
1388 | if ((*count)++ >= start_offset) { | |
1389 | unsigned int namelen; | |
1390 | ||
1391 | namelen = sprintf(buffer + *pos, "%s\n", t->name); | |
1392 | if (*pos + namelen > length) { | |
1393 | /* Stop iterating */ | |
1394 | return 1; | |
1395 | } | |
1396 | *pos += namelen; | |
1397 | } | |
1398 | return 0; | |
1399 | } | |
1400 | ||
1401 | static int arpt_get_tables(char *buffer, char **start, off_t offset, int length) | |
1402 | { | |
1403 | off_t pos = 0; | |
1404 | unsigned int count = 0; | |
1405 | ||
1406 | if (down_interruptible(&arpt_mutex) != 0) | |
1407 | return 0; | |
1408 | ||
1409 | LIST_FIND(&arpt_tables, print_name, struct arpt_table *, | |
1410 | offset, buffer, length, &pos, &count); | |
1411 | ||
1412 | up(&arpt_mutex); | |
1413 | ||
1414 | /* `start' hack - see fs/proc/generic.c line ~105 */ | |
1415 | *start=(char *)((unsigned long)count-offset); | |
1416 | return pos; | |
1417 | } | |
1418 | #endif /*CONFIG_PROC_FS*/ | |
1419 | ||
1420 | static int __init init(void) | |
1421 | { | |
1422 | int ret; | |
1423 | ||
1424 | /* Noone else will be downing sem now, so we won't sleep */ | |
1425 | down(&arpt_mutex); | |
1426 | list_append(&arpt_target, &arpt_standard_target); | |
1427 | list_append(&arpt_target, &arpt_error_target); | |
1428 | up(&arpt_mutex); | |
1429 | ||
1430 | /* Register setsockopt */ | |
1431 | ret = nf_register_sockopt(&arpt_sockopts); | |
1432 | if (ret < 0) { | |
1433 | duprintf("Unable to register sockopts.\n"); | |
1434 | return ret; | |
1435 | } | |
1436 | ||
1437 | #ifdef CONFIG_PROC_FS | |
1438 | { | |
1439 | struct proc_dir_entry *proc; | |
1440 | ||
1441 | proc = proc_net_create("arp_tables_names", 0, arpt_get_tables); | |
1442 | if (!proc) { | |
1443 | nf_unregister_sockopt(&arpt_sockopts); | |
1444 | return -ENOMEM; | |
1445 | } | |
1446 | proc->owner = THIS_MODULE; | |
1447 | } | |
1448 | #endif | |
1449 | ||
1450 | printk("arp_tables: (C) 2002 David S. Miller\n"); | |
1451 | return 0; | |
1452 | } | |
1453 | ||
1454 | static void __exit fini(void) | |
1455 | { | |
1456 | nf_unregister_sockopt(&arpt_sockopts); | |
1457 | #ifdef CONFIG_PROC_FS | |
1458 | proc_net_remove("arp_tables_names"); | |
1459 | #endif | |
1460 | } | |
1461 | ||
1462 | EXPORT_SYMBOL(arpt_register_table); | |
1463 | EXPORT_SYMBOL(arpt_unregister_table); | |
1464 | EXPORT_SYMBOL(arpt_do_table); | |
1465 | EXPORT_SYMBOL(arpt_register_target); | |
1466 | EXPORT_SYMBOL(arpt_unregister_target); | |
1467 | ||
1468 | module_init(init); | |
1469 | module_exit(fini); |