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> | |
16 | #include <linux/if_arp.h> | |
17 | #include <linux/kmod.h> | |
18 | #include <linux/vmalloc.h> | |
19 | #include <linux/proc_fs.h> | |
20 | #include <linux/module.h> | |
21 | #include <linux/init.h> | |
22 | ||
23 | #include <asm/uaccess.h> | |
24 | #include <asm/semaphore.h> | |
25 | ||
26 | #include <linux/netfilter_arp/arp_tables.h> | |
27 | ||
28 | MODULE_LICENSE("GPL"); | |
29 | MODULE_AUTHOR("David S. Miller <davem@redhat.com>"); | |
30 | MODULE_DESCRIPTION("arptables core"); | |
31 | ||
32 | /*#define DEBUG_ARP_TABLES*/ | |
33 | /*#define DEBUG_ARP_TABLES_USER*/ | |
34 | ||
35 | #ifdef DEBUG_ARP_TABLES | |
36 | #define dprintf(format, args...) printk(format , ## args) | |
37 | #else | |
38 | #define dprintf(format, args...) | |
39 | #endif | |
40 | ||
41 | #ifdef DEBUG_ARP_TABLES_USER | |
42 | #define duprintf(format, args...) printk(format , ## args) | |
43 | #else | |
44 | #define duprintf(format, args...) | |
45 | #endif | |
46 | ||
47 | #ifdef CONFIG_NETFILTER_DEBUG | |
48 | #define ARP_NF_ASSERT(x) \ | |
49 | do { \ | |
50 | if (!(x)) \ | |
51 | printk("ARP_NF_ASSERT: %s:%s:%u\n", \ | |
52 | __FUNCTION__, __FILE__, __LINE__); \ | |
53 | } while(0) | |
54 | #else | |
55 | #define ARP_NF_ASSERT(x) | |
56 | #endif | |
57 | #define SMP_ALIGN(x) (((x) + SMP_CACHE_BYTES-1) & ~(SMP_CACHE_BYTES-1)) | |
58 | ||
59 | static DECLARE_MUTEX(arpt_mutex); | |
60 | ||
61 | #define ASSERT_READ_LOCK(x) ARP_NF_ASSERT(down_trylock(&arpt_mutex) != 0) | |
62 | #define ASSERT_WRITE_LOCK(x) ARP_NF_ASSERT(down_trylock(&arpt_mutex) != 0) | |
1da177e4 LT |
63 | #include <linux/netfilter_ipv4/listhelp.h> |
64 | ||
65 | struct arpt_table_info { | |
66 | unsigned int size; | |
67 | unsigned int number; | |
68 | unsigned int initial_entries; | |
69 | unsigned int hook_entry[NF_ARP_NUMHOOKS]; | |
70 | unsigned int underflow[NF_ARP_NUMHOOKS]; | |
31836064 | 71 | void *entries[NR_CPUS]; |
1da177e4 LT |
72 | }; |
73 | ||
74 | static LIST_HEAD(arpt_target); | |
75 | static LIST_HEAD(arpt_tables); | |
31836064 | 76 | #define SET_COUNTER(c,b,p) do { (c).bcnt = (b); (c).pcnt = (p); } while(0) |
1da177e4 LT |
77 | #define ADD_COUNTER(c,b,p) do { (c).bcnt += (b); (c).pcnt += (p); } while(0) |
78 | ||
1da177e4 LT |
79 | static inline int arp_devaddr_compare(const struct arpt_devaddr_info *ap, |
80 | char *hdr_addr, int len) | |
81 | { | |
82 | int i, ret; | |
83 | ||
84 | if (len > ARPT_DEV_ADDR_LEN_MAX) | |
85 | len = ARPT_DEV_ADDR_LEN_MAX; | |
86 | ||
87 | ret = 0; | |
88 | for (i = 0; i < len; i++) | |
89 | ret |= (hdr_addr[i] ^ ap->addr[i]) & ap->mask[i]; | |
90 | ||
91 | return (ret != 0); | |
92 | } | |
93 | ||
94 | /* Returns whether packet matches rule or not. */ | |
95 | static inline int arp_packet_match(const struct arphdr *arphdr, | |
96 | struct net_device *dev, | |
97 | const char *indev, | |
98 | const char *outdev, | |
99 | const struct arpt_arp *arpinfo) | |
100 | { | |
101 | char *arpptr = (char *)(arphdr + 1); | |
102 | char *src_devaddr, *tgt_devaddr; | |
103 | u32 src_ipaddr, tgt_ipaddr; | |
104 | int i, ret; | |
105 | ||
106 | #define FWINV(bool,invflg) ((bool) ^ !!(arpinfo->invflags & invflg)) | |
107 | ||
108 | if (FWINV((arphdr->ar_op & arpinfo->arpop_mask) != arpinfo->arpop, | |
109 | ARPT_INV_ARPOP)) { | |
110 | dprintf("ARP operation field mismatch.\n"); | |
111 | dprintf("ar_op: %04x info->arpop: %04x info->arpop_mask: %04x\n", | |
112 | arphdr->ar_op, arpinfo->arpop, arpinfo->arpop_mask); | |
113 | return 0; | |
114 | } | |
115 | ||
116 | if (FWINV((arphdr->ar_hrd & arpinfo->arhrd_mask) != arpinfo->arhrd, | |
117 | ARPT_INV_ARPHRD)) { | |
118 | dprintf("ARP hardware address format mismatch.\n"); | |
119 | dprintf("ar_hrd: %04x info->arhrd: %04x info->arhrd_mask: %04x\n", | |
120 | arphdr->ar_hrd, arpinfo->arhrd, arpinfo->arhrd_mask); | |
121 | return 0; | |
122 | } | |
123 | ||
124 | if (FWINV((arphdr->ar_pro & arpinfo->arpro_mask) != arpinfo->arpro, | |
125 | ARPT_INV_ARPPRO)) { | |
126 | dprintf("ARP protocol address format mismatch.\n"); | |
127 | dprintf("ar_pro: %04x info->arpro: %04x info->arpro_mask: %04x\n", | |
128 | arphdr->ar_pro, arpinfo->arpro, arpinfo->arpro_mask); | |
129 | return 0; | |
130 | } | |
131 | ||
132 | if (FWINV((arphdr->ar_hln & arpinfo->arhln_mask) != arpinfo->arhln, | |
133 | ARPT_INV_ARPHLN)) { | |
134 | dprintf("ARP hardware address length mismatch.\n"); | |
135 | dprintf("ar_hln: %02x info->arhln: %02x info->arhln_mask: %02x\n", | |
136 | arphdr->ar_hln, arpinfo->arhln, arpinfo->arhln_mask); | |
137 | return 0; | |
138 | } | |
139 | ||
140 | src_devaddr = arpptr; | |
141 | arpptr += dev->addr_len; | |
142 | memcpy(&src_ipaddr, arpptr, sizeof(u32)); | |
143 | arpptr += sizeof(u32); | |
144 | tgt_devaddr = arpptr; | |
145 | arpptr += dev->addr_len; | |
146 | memcpy(&tgt_ipaddr, arpptr, sizeof(u32)); | |
147 | ||
148 | if (FWINV(arp_devaddr_compare(&arpinfo->src_devaddr, src_devaddr, dev->addr_len), | |
149 | ARPT_INV_SRCDEVADDR) || | |
150 | FWINV(arp_devaddr_compare(&arpinfo->tgt_devaddr, tgt_devaddr, dev->addr_len), | |
151 | ARPT_INV_TGTDEVADDR)) { | |
152 | dprintf("Source or target device address mismatch.\n"); | |
153 | ||
154 | return 0; | |
155 | } | |
156 | ||
157 | if (FWINV((src_ipaddr & arpinfo->smsk.s_addr) != arpinfo->src.s_addr, | |
158 | ARPT_INV_SRCIP) || | |
159 | FWINV(((tgt_ipaddr & arpinfo->tmsk.s_addr) != arpinfo->tgt.s_addr), | |
160 | ARPT_INV_TGTIP)) { | |
161 | dprintf("Source or target IP address mismatch.\n"); | |
162 | ||
163 | dprintf("SRC: %u.%u.%u.%u. Mask: %u.%u.%u.%u. Target: %u.%u.%u.%u.%s\n", | |
164 | NIPQUAD(src_ipaddr), | |
165 | NIPQUAD(arpinfo->smsk.s_addr), | |
166 | NIPQUAD(arpinfo->src.s_addr), | |
167 | arpinfo->invflags & ARPT_INV_SRCIP ? " (INV)" : ""); | |
168 | dprintf("TGT: %u.%u.%u.%u Mask: %u.%u.%u.%u Target: %u.%u.%u.%u.%s\n", | |
169 | NIPQUAD(tgt_ipaddr), | |
170 | NIPQUAD(arpinfo->tmsk.s_addr), | |
171 | NIPQUAD(arpinfo->tgt.s_addr), | |
172 | arpinfo->invflags & ARPT_INV_TGTIP ? " (INV)" : ""); | |
173 | return 0; | |
174 | } | |
175 | ||
176 | /* Look for ifname matches. */ | |
177 | for (i = 0, ret = 0; i < IFNAMSIZ; i++) { | |
178 | ret |= (indev[i] ^ arpinfo->iniface[i]) | |
179 | & arpinfo->iniface_mask[i]; | |
180 | } | |
181 | ||
182 | if (FWINV(ret != 0, ARPT_INV_VIA_IN)) { | |
183 | dprintf("VIA in mismatch (%s vs %s).%s\n", | |
184 | indev, arpinfo->iniface, | |
185 | arpinfo->invflags&ARPT_INV_VIA_IN ?" (INV)":""); | |
186 | return 0; | |
187 | } | |
188 | ||
189 | for (i = 0, ret = 0; i < IFNAMSIZ/sizeof(unsigned long); i++) { | |
190 | unsigned long odev; | |
191 | memcpy(&odev, outdev + i*sizeof(unsigned long), | |
192 | sizeof(unsigned long)); | |
193 | ret |= (odev | |
194 | ^ ((const unsigned long *)arpinfo->outiface)[i]) | |
195 | & ((const unsigned long *)arpinfo->outiface_mask)[i]; | |
196 | } | |
197 | ||
198 | if (FWINV(ret != 0, ARPT_INV_VIA_OUT)) { | |
199 | dprintf("VIA out mismatch (%s vs %s).%s\n", | |
200 | outdev, arpinfo->outiface, | |
201 | arpinfo->invflags&ARPT_INV_VIA_OUT ?" (INV)":""); | |
202 | return 0; | |
203 | } | |
204 | ||
205 | return 1; | |
206 | } | |
207 | ||
208 | static inline int arp_checkentry(const struct arpt_arp *arp) | |
209 | { | |
210 | if (arp->flags & ~ARPT_F_MASK) { | |
211 | duprintf("Unknown flag bits set: %08X\n", | |
212 | arp->flags & ~ARPT_F_MASK); | |
213 | return 0; | |
214 | } | |
215 | if (arp->invflags & ~ARPT_INV_MASK) { | |
216 | duprintf("Unknown invflag bits set: %08X\n", | |
217 | arp->invflags & ~ARPT_INV_MASK); | |
218 | return 0; | |
219 | } | |
220 | ||
221 | return 1; | |
222 | } | |
223 | ||
224 | static unsigned int arpt_error(struct sk_buff **pskb, | |
225 | unsigned int hooknum, | |
226 | const struct net_device *in, | |
227 | const struct net_device *out, | |
228 | const void *targinfo, | |
229 | void *userinfo) | |
230 | { | |
231 | if (net_ratelimit()) | |
232 | printk("arp_tables: error: '%s'\n", (char *)targinfo); | |
233 | ||
234 | return NF_DROP; | |
235 | } | |
236 | ||
237 | static inline struct arpt_entry *get_entry(void *base, unsigned int offset) | |
238 | { | |
239 | return (struct arpt_entry *)(base + offset); | |
240 | } | |
241 | ||
242 | unsigned int arpt_do_table(struct sk_buff **pskb, | |
243 | unsigned int hook, | |
244 | const struct net_device *in, | |
245 | const struct net_device *out, | |
246 | struct arpt_table *table, | |
247 | void *userdata) | |
248 | { | |
249 | static const char nulldevname[IFNAMSIZ]; | |
250 | unsigned int verdict = NF_DROP; | |
251 | struct arphdr *arp; | |
252 | int hotdrop = 0; | |
253 | struct arpt_entry *e, *back; | |
254 | const char *indev, *outdev; | |
255 | void *table_base; | |
256 | ||
257 | /* ARP header, plus 2 device addresses, plus 2 IP addresses. */ | |
258 | if (!pskb_may_pull((*pskb), (sizeof(struct arphdr) + | |
259 | (2 * (*pskb)->dev->addr_len) + | |
260 | (2 * sizeof(u32))))) | |
261 | return NF_DROP; | |
262 | ||
263 | indev = in ? in->name : nulldevname; | |
264 | outdev = out ? out->name : nulldevname; | |
265 | ||
266 | read_lock_bh(&table->lock); | |
31836064 | 267 | table_base = (void *)table->private->entries[smp_processor_id()]; |
1da177e4 LT |
268 | e = get_entry(table_base, table->private->hook_entry[hook]); |
269 | back = get_entry(table_base, table->private->underflow[hook]); | |
270 | ||
271 | arp = (*pskb)->nh.arph; | |
272 | do { | |
273 | if (arp_packet_match(arp, (*pskb)->dev, indev, outdev, &e->arp)) { | |
274 | struct arpt_entry_target *t; | |
275 | int hdr_len; | |
276 | ||
277 | hdr_len = sizeof(*arp) + (2 * sizeof(struct in_addr)) + | |
278 | (2 * (*pskb)->dev->addr_len); | |
279 | ADD_COUNTER(e->counters, hdr_len, 1); | |
280 | ||
281 | t = arpt_get_target(e); | |
282 | ||
283 | /* Standard target? */ | |
284 | if (!t->u.kernel.target->target) { | |
285 | int v; | |
286 | ||
287 | v = ((struct arpt_standard_target *)t)->verdict; | |
288 | if (v < 0) { | |
289 | /* Pop from stack? */ | |
290 | if (v != ARPT_RETURN) { | |
291 | verdict = (unsigned)(-v) - 1; | |
292 | break; | |
293 | } | |
294 | e = back; | |
295 | back = get_entry(table_base, | |
296 | back->comefrom); | |
297 | continue; | |
298 | } | |
299 | if (table_base + v | |
300 | != (void *)e + e->next_offset) { | |
301 | /* Save old back ptr in next entry */ | |
302 | struct arpt_entry *next | |
303 | = (void *)e + e->next_offset; | |
304 | next->comefrom = | |
305 | (void *)back - table_base; | |
306 | ||
307 | /* set back pointer to next entry */ | |
308 | back = next; | |
309 | } | |
310 | ||
311 | e = get_entry(table_base, v); | |
312 | } else { | |
313 | /* Targets which reenter must return | |
314 | * abs. verdicts | |
315 | */ | |
316 | verdict = t->u.kernel.target->target(pskb, | |
317 | hook, | |
318 | in, out, | |
319 | t->data, | |
320 | userdata); | |
321 | ||
322 | /* Target might have changed stuff. */ | |
323 | arp = (*pskb)->nh.arph; | |
324 | ||
325 | if (verdict == ARPT_CONTINUE) | |
326 | e = (void *)e + e->next_offset; | |
327 | else | |
328 | /* Verdict */ | |
329 | break; | |
330 | } | |
331 | } else { | |
332 | e = (void *)e + e->next_offset; | |
333 | } | |
334 | } while (!hotdrop); | |
335 | read_unlock_bh(&table->lock); | |
336 | ||
337 | if (hotdrop) | |
338 | return NF_DROP; | |
339 | else | |
340 | return verdict; | |
341 | } | |
342 | ||
6b7d31fc HW |
343 | /* |
344 | * These are weird, but module loading must not be done with mutex | |
345 | * held (since they will register), and we have to have a single | |
346 | * function to use try_then_request_module(). | |
347 | */ | |
348 | ||
349 | /* Find table by name, grabs mutex & ref. Returns ERR_PTR() on error. */ | |
350 | static inline struct arpt_table *find_table_lock(const char *name) | |
1da177e4 | 351 | { |
6b7d31fc | 352 | struct arpt_table *t; |
1da177e4 | 353 | |
6b7d31fc HW |
354 | if (down_interruptible(&arpt_mutex) != 0) |
355 | return ERR_PTR(-EINTR); | |
1da177e4 | 356 | |
6b7d31fc HW |
357 | list_for_each_entry(t, &arpt_tables, list) |
358 | if (strcmp(t->name, name) == 0 && try_module_get(t->me)) | |
359 | return t; | |
360 | up(&arpt_mutex); | |
361 | return NULL; | |
1da177e4 LT |
362 | } |
363 | ||
1da177e4 | 364 | |
6b7d31fc HW |
365 | /* Find target, grabs ref. Returns ERR_PTR() on error. */ |
366 | static inline struct arpt_target *find_target(const char *name, u8 revision) | |
367 | { | |
368 | struct arpt_target *t; | |
369 | int err = 0; | |
370 | ||
371 | if (down_interruptible(&arpt_mutex) != 0) | |
372 | return ERR_PTR(-EINTR); | |
373 | ||
374 | list_for_each_entry(t, &arpt_target, list) { | |
375 | if (strcmp(t->name, name) == 0) { | |
376 | if (t->revision == revision) { | |
377 | if (try_module_get(t->me)) { | |
378 | up(&arpt_mutex); | |
379 | return t; | |
380 | } | |
381 | } else | |
382 | err = -EPROTOTYPE; /* Found something. */ | |
383 | } | |
1da177e4 | 384 | } |
6b7d31fc HW |
385 | up(&arpt_mutex); |
386 | return ERR_PTR(err); | |
387 | } | |
1da177e4 | 388 | |
6b7d31fc HW |
389 | struct arpt_target *arpt_find_target(const char *name, u8 revision) |
390 | { | |
391 | struct arpt_target *target; | |
392 | ||
393 | target = try_then_request_module(find_target(name, revision), | |
394 | "arpt_%s", name); | |
395 | if (IS_ERR(target) || !target) | |
396 | return NULL; | |
397 | return target; | |
1da177e4 | 398 | } |
1da177e4 | 399 | |
6b7d31fc | 400 | static int target_revfn(const char *name, u8 revision, int *bestp) |
1da177e4 | 401 | { |
6b7d31fc HW |
402 | struct arpt_target *t; |
403 | int have_rev = 0; | |
404 | ||
405 | list_for_each_entry(t, &arpt_target, list) { | |
406 | if (strcmp(t->name, name) == 0) { | |
407 | if (t->revision > *bestp) | |
408 | *bestp = t->revision; | |
409 | if (t->revision == revision) | |
410 | have_rev =1; | |
411 | } | |
412 | } | |
413 | return have_rev; | |
1da177e4 LT |
414 | } |
415 | ||
6b7d31fc HW |
416 | /* Returns true or false (if no such extension at all) */ |
417 | static inline int find_revision(const char *name, u8 revision, | |
418 | int (*revfn)(const char *, u8, int *), | |
419 | int *err) | |
1da177e4 | 420 | { |
6b7d31fc HW |
421 | int have_rev, best = -1; |
422 | ||
423 | if (down_interruptible(&arpt_mutex) != 0) { | |
424 | *err = -EINTR; | |
425 | return 1; | |
426 | } | |
427 | have_rev = revfn(name, revision, &best); | |
428 | up(&arpt_mutex); | |
429 | ||
430 | /* Nothing at all? Return 0 to try loading module. */ | |
431 | if (best == -1) { | |
432 | *err = -ENOENT; | |
433 | return 0; | |
434 | } | |
435 | ||
436 | *err = best; | |
437 | if (!have_rev) | |
438 | *err = -EPROTONOSUPPORT; | |
439 | return 1; | |
1da177e4 LT |
440 | } |
441 | ||
6b7d31fc | 442 | |
1da177e4 LT |
443 | /* All zeroes == unconditional rule. */ |
444 | static inline int unconditional(const struct arpt_arp *arp) | |
445 | { | |
446 | unsigned int i; | |
447 | ||
448 | for (i = 0; i < sizeof(*arp)/sizeof(__u32); i++) | |
449 | if (((__u32 *)arp)[i]) | |
450 | return 0; | |
451 | ||
452 | return 1; | |
453 | } | |
454 | ||
455 | /* Figures out from what hook each rule can be called: returns 0 if | |
456 | * there are loops. Puts hook bitmask in comefrom. | |
457 | */ | |
31836064 ED |
458 | static int mark_source_chains(struct arpt_table_info *newinfo, |
459 | unsigned int valid_hooks, void *entry0) | |
1da177e4 LT |
460 | { |
461 | unsigned int hook; | |
462 | ||
463 | /* No recursion; use packet counter to save back ptrs (reset | |
464 | * to 0 as we leave), and comefrom to save source hook bitmask. | |
465 | */ | |
466 | for (hook = 0; hook < NF_ARP_NUMHOOKS; hook++) { | |
467 | unsigned int pos = newinfo->hook_entry[hook]; | |
468 | struct arpt_entry *e | |
31836064 | 469 | = (struct arpt_entry *)(entry0 + pos); |
1da177e4 LT |
470 | |
471 | if (!(valid_hooks & (1 << hook))) | |
472 | continue; | |
473 | ||
474 | /* Set initial back pointer. */ | |
475 | e->counters.pcnt = pos; | |
476 | ||
477 | for (;;) { | |
478 | struct arpt_standard_target *t | |
479 | = (void *)arpt_get_target(e); | |
480 | ||
481 | if (e->comefrom & (1 << NF_ARP_NUMHOOKS)) { | |
482 | printk("arptables: loop hook %u pos %u %08X.\n", | |
483 | hook, pos, e->comefrom); | |
484 | return 0; | |
485 | } | |
486 | e->comefrom | |
487 | |= ((1 << hook) | (1 << NF_ARP_NUMHOOKS)); | |
488 | ||
489 | /* Unconditional return/END. */ | |
490 | if (e->target_offset == sizeof(struct arpt_entry) | |
491 | && (strcmp(t->target.u.user.name, | |
492 | ARPT_STANDARD_TARGET) == 0) | |
493 | && t->verdict < 0 | |
494 | && unconditional(&e->arp)) { | |
495 | unsigned int oldpos, size; | |
496 | ||
497 | /* Return: backtrack through the last | |
498 | * big jump. | |
499 | */ | |
500 | do { | |
501 | e->comefrom ^= (1<<NF_ARP_NUMHOOKS); | |
502 | oldpos = pos; | |
503 | pos = e->counters.pcnt; | |
504 | e->counters.pcnt = 0; | |
505 | ||
506 | /* We're at the start. */ | |
507 | if (pos == oldpos) | |
508 | goto next; | |
509 | ||
510 | e = (struct arpt_entry *) | |
31836064 | 511 | (entry0 + pos); |
1da177e4 LT |
512 | } while (oldpos == pos + e->next_offset); |
513 | ||
514 | /* Move along one */ | |
515 | size = e->next_offset; | |
516 | e = (struct arpt_entry *) | |
31836064 | 517 | (entry0 + pos + size); |
1da177e4 LT |
518 | e->counters.pcnt = pos; |
519 | pos += size; | |
520 | } else { | |
521 | int newpos = t->verdict; | |
522 | ||
523 | if (strcmp(t->target.u.user.name, | |
524 | ARPT_STANDARD_TARGET) == 0 | |
525 | && newpos >= 0) { | |
526 | /* This a jump; chase it. */ | |
527 | duprintf("Jump rule %u -> %u\n", | |
528 | pos, newpos); | |
529 | } else { | |
530 | /* ... this is a fallthru */ | |
531 | newpos = pos + e->next_offset; | |
532 | } | |
533 | e = (struct arpt_entry *) | |
31836064 | 534 | (entry0 + newpos); |
1da177e4 LT |
535 | e->counters.pcnt = pos; |
536 | pos = newpos; | |
537 | } | |
538 | } | |
539 | next: | |
540 | duprintf("Finished chain %u\n", hook); | |
541 | } | |
542 | return 1; | |
543 | } | |
544 | ||
545 | static inline int standard_check(const struct arpt_entry_target *t, | |
546 | unsigned int max_offset) | |
547 | { | |
548 | struct arpt_standard_target *targ = (void *)t; | |
549 | ||
550 | /* Check standard info. */ | |
551 | if (t->u.target_size | |
552 | != ARPT_ALIGN(sizeof(struct arpt_standard_target))) { | |
553 | duprintf("arpt_standard_check: target size %u != %Zu\n", | |
554 | t->u.target_size, | |
555 | ARPT_ALIGN(sizeof(struct arpt_standard_target))); | |
556 | return 0; | |
557 | } | |
558 | ||
559 | if (targ->verdict >= 0 | |
560 | && targ->verdict > max_offset - sizeof(struct arpt_entry)) { | |
561 | duprintf("arpt_standard_check: bad verdict (%i)\n", | |
562 | targ->verdict); | |
563 | return 0; | |
564 | } | |
565 | ||
566 | if (targ->verdict < -NF_MAX_VERDICT - 1) { | |
567 | duprintf("arpt_standard_check: bad negative verdict (%i)\n", | |
568 | targ->verdict); | |
569 | return 0; | |
570 | } | |
571 | return 1; | |
572 | } | |
573 | ||
574 | static struct arpt_target arpt_standard_target; | |
575 | ||
576 | static inline int check_entry(struct arpt_entry *e, const char *name, unsigned int size, | |
577 | unsigned int *i) | |
578 | { | |
579 | struct arpt_entry_target *t; | |
580 | struct arpt_target *target; | |
581 | int ret; | |
582 | ||
583 | if (!arp_checkentry(&e->arp)) { | |
584 | duprintf("arp_tables: arp check failed %p %s.\n", e, name); | |
585 | return -EINVAL; | |
586 | } | |
587 | ||
588 | t = arpt_get_target(e); | |
6b7d31fc HW |
589 | target = try_then_request_module(find_target(t->u.user.name, |
590 | t->u.user.revision), | |
591 | "arpt_%s", t->u.user.name); | |
592 | if (IS_ERR(target) || !target) { | |
1da177e4 | 593 | duprintf("check_entry: `%s' not found\n", t->u.user.name); |
6b7d31fc | 594 | ret = target ? PTR_ERR(target) : -ENOENT; |
1da177e4 LT |
595 | goto out; |
596 | } | |
1da177e4 | 597 | t->u.kernel.target = target; |
1da177e4 LT |
598 | |
599 | if (t->u.kernel.target == &arpt_standard_target) { | |
600 | if (!standard_check(t, size)) { | |
601 | ret = -EINVAL; | |
602 | goto out; | |
603 | } | |
604 | } else if (t->u.kernel.target->checkentry | |
605 | && !t->u.kernel.target->checkentry(name, e, t->data, | |
606 | t->u.target_size | |
607 | - sizeof(*t), | |
608 | e->comefrom)) { | |
609 | module_put(t->u.kernel.target->me); | |
610 | duprintf("arp_tables: check failed for `%s'.\n", | |
611 | t->u.kernel.target->name); | |
612 | ret = -EINVAL; | |
613 | goto out; | |
614 | } | |
615 | ||
616 | (*i)++; | |
617 | return 0; | |
618 | ||
1da177e4 LT |
619 | out: |
620 | return ret; | |
621 | } | |
622 | ||
623 | static inline int check_entry_size_and_hooks(struct arpt_entry *e, | |
624 | struct arpt_table_info *newinfo, | |
625 | unsigned char *base, | |
626 | unsigned char *limit, | |
627 | const unsigned int *hook_entries, | |
628 | const unsigned int *underflows, | |
629 | unsigned int *i) | |
630 | { | |
631 | unsigned int h; | |
632 | ||
633 | if ((unsigned long)e % __alignof__(struct arpt_entry) != 0 | |
634 | || (unsigned char *)e + sizeof(struct arpt_entry) >= limit) { | |
635 | duprintf("Bad offset %p\n", e); | |
636 | return -EINVAL; | |
637 | } | |
638 | ||
639 | if (e->next_offset | |
640 | < sizeof(struct arpt_entry) + sizeof(struct arpt_entry_target)) { | |
641 | duprintf("checking: element %p size %u\n", | |
642 | e, e->next_offset); | |
643 | return -EINVAL; | |
644 | } | |
645 | ||
646 | /* Check hooks & underflows */ | |
647 | for (h = 0; h < NF_ARP_NUMHOOKS; h++) { | |
648 | if ((unsigned char *)e - base == hook_entries[h]) | |
649 | newinfo->hook_entry[h] = hook_entries[h]; | |
650 | if ((unsigned char *)e - base == underflows[h]) | |
651 | newinfo->underflow[h] = underflows[h]; | |
652 | } | |
653 | ||
654 | /* FIXME: underflows must be unconditional, standard verdicts | |
655 | < 0 (not ARPT_RETURN). --RR */ | |
656 | ||
657 | /* Clear counters and comefrom */ | |
658 | e->counters = ((struct arpt_counters) { 0, 0 }); | |
659 | e->comefrom = 0; | |
660 | ||
661 | (*i)++; | |
662 | return 0; | |
663 | } | |
664 | ||
665 | static inline int cleanup_entry(struct arpt_entry *e, unsigned int *i) | |
666 | { | |
667 | struct arpt_entry_target *t; | |
668 | ||
669 | if (i && (*i)-- == 0) | |
670 | return 1; | |
671 | ||
672 | t = arpt_get_target(e); | |
673 | if (t->u.kernel.target->destroy) | |
674 | t->u.kernel.target->destroy(t->data, | |
675 | t->u.target_size - sizeof(*t)); | |
676 | module_put(t->u.kernel.target->me); | |
677 | return 0; | |
678 | } | |
679 | ||
680 | /* Checks and translates the user-supplied table segment (held in | |
681 | * newinfo). | |
682 | */ | |
683 | static int translate_table(const char *name, | |
684 | unsigned int valid_hooks, | |
685 | struct arpt_table_info *newinfo, | |
31836064 | 686 | void *entry0, |
1da177e4 LT |
687 | unsigned int size, |
688 | unsigned int number, | |
689 | const unsigned int *hook_entries, | |
690 | const unsigned int *underflows) | |
691 | { | |
692 | unsigned int i; | |
693 | int ret; | |
694 | ||
695 | newinfo->size = size; | |
696 | newinfo->number = number; | |
697 | ||
698 | /* Init all hooks to impossible value. */ | |
699 | for (i = 0; i < NF_ARP_NUMHOOKS; i++) { | |
700 | newinfo->hook_entry[i] = 0xFFFFFFFF; | |
701 | newinfo->underflow[i] = 0xFFFFFFFF; | |
702 | } | |
703 | ||
704 | duprintf("translate_table: size %u\n", newinfo->size); | |
705 | i = 0; | |
706 | ||
707 | /* Walk through entries, checking offsets. */ | |
31836064 | 708 | ret = ARPT_ENTRY_ITERATE(entry0, newinfo->size, |
1da177e4 LT |
709 | check_entry_size_and_hooks, |
710 | newinfo, | |
31836064 ED |
711 | entry0, |
712 | entry0 + size, | |
1da177e4 LT |
713 | hook_entries, underflows, &i); |
714 | duprintf("translate_table: ARPT_ENTRY_ITERATE gives %d\n", ret); | |
715 | if (ret != 0) | |
716 | return ret; | |
717 | ||
718 | if (i != number) { | |
719 | duprintf("translate_table: %u not %u entries\n", | |
720 | i, number); | |
721 | return -EINVAL; | |
722 | } | |
723 | ||
724 | /* Check hooks all assigned */ | |
725 | for (i = 0; i < NF_ARP_NUMHOOKS; i++) { | |
726 | /* Only hooks which are valid */ | |
727 | if (!(valid_hooks & (1 << i))) | |
728 | continue; | |
729 | if (newinfo->hook_entry[i] == 0xFFFFFFFF) { | |
730 | duprintf("Invalid hook entry %u %u\n", | |
731 | i, hook_entries[i]); | |
732 | return -EINVAL; | |
733 | } | |
734 | if (newinfo->underflow[i] == 0xFFFFFFFF) { | |
735 | duprintf("Invalid underflow %u %u\n", | |
736 | i, underflows[i]); | |
737 | return -EINVAL; | |
738 | } | |
739 | } | |
740 | ||
31836064 | 741 | if (!mark_source_chains(newinfo, valid_hooks, entry0)) { |
1da177e4 LT |
742 | duprintf("Looping hook\n"); |
743 | return -ELOOP; | |
744 | } | |
745 | ||
746 | /* Finally, each sanity check must pass */ | |
747 | i = 0; | |
31836064 | 748 | ret = ARPT_ENTRY_ITERATE(entry0, newinfo->size, |
1da177e4 LT |
749 | check_entry, name, size, &i); |
750 | ||
751 | if (ret != 0) { | |
31836064 | 752 | ARPT_ENTRY_ITERATE(entry0, newinfo->size, |
1da177e4 LT |
753 | cleanup_entry, &i); |
754 | return ret; | |
755 | } | |
756 | ||
757 | /* And one copy for every other CPU */ | |
c8923c6b | 758 | for_each_cpu(i) { |
31836064 ED |
759 | if (newinfo->entries[i] && newinfo->entries[i] != entry0) |
760 | memcpy(newinfo->entries[i], entry0, newinfo->size); | |
1da177e4 LT |
761 | } |
762 | ||
763 | return ret; | |
764 | } | |
765 | ||
766 | static struct arpt_table_info *replace_table(struct arpt_table *table, | |
767 | unsigned int num_counters, | |
768 | struct arpt_table_info *newinfo, | |
769 | int *error) | |
770 | { | |
771 | struct arpt_table_info *oldinfo; | |
772 | ||
773 | /* Do the substitution. */ | |
774 | write_lock_bh(&table->lock); | |
775 | /* Check inside lock: is the old number correct? */ | |
776 | if (num_counters != table->private->number) { | |
777 | duprintf("num_counters != table->private->number (%u/%u)\n", | |
778 | num_counters, table->private->number); | |
779 | write_unlock_bh(&table->lock); | |
780 | *error = -EAGAIN; | |
781 | return NULL; | |
782 | } | |
783 | oldinfo = table->private; | |
784 | table->private = newinfo; | |
785 | newinfo->initial_entries = oldinfo->initial_entries; | |
786 | write_unlock_bh(&table->lock); | |
787 | ||
788 | return oldinfo; | |
789 | } | |
790 | ||
791 | /* Gets counters. */ | |
792 | static inline int add_entry_to_counter(const struct arpt_entry *e, | |
793 | struct arpt_counters total[], | |
794 | unsigned int *i) | |
795 | { | |
796 | ADD_COUNTER(total[*i], e->counters.bcnt, e->counters.pcnt); | |
797 | ||
798 | (*i)++; | |
799 | return 0; | |
800 | } | |
801 | ||
31836064 ED |
802 | static inline int set_entry_to_counter(const struct arpt_entry *e, |
803 | struct arpt_counters total[], | |
804 | unsigned int *i) | |
805 | { | |
806 | SET_COUNTER(total[*i], e->counters.bcnt, e->counters.pcnt); | |
807 | ||
808 | (*i)++; | |
809 | return 0; | |
810 | } | |
811 | ||
1da177e4 LT |
812 | static void get_counters(const struct arpt_table_info *t, |
813 | struct arpt_counters counters[]) | |
814 | { | |
815 | unsigned int cpu; | |
816 | unsigned int i; | |
31836064 ED |
817 | unsigned int curcpu; |
818 | ||
819 | /* Instead of clearing (by a previous call to memset()) | |
820 | * the counters and using adds, we set the counters | |
821 | * with data used by 'current' CPU | |
822 | * We dont care about preemption here. | |
823 | */ | |
824 | curcpu = raw_smp_processor_id(); | |
825 | ||
826 | i = 0; | |
827 | ARPT_ENTRY_ITERATE(t->entries[curcpu], | |
828 | t->size, | |
829 | set_entry_to_counter, | |
830 | counters, | |
831 | &i); | |
1da177e4 | 832 | |
c8923c6b | 833 | for_each_cpu(cpu) { |
31836064 ED |
834 | if (cpu == curcpu) |
835 | continue; | |
1da177e4 | 836 | i = 0; |
31836064 | 837 | ARPT_ENTRY_ITERATE(t->entries[cpu], |
1da177e4 LT |
838 | t->size, |
839 | add_entry_to_counter, | |
840 | counters, | |
841 | &i); | |
842 | } | |
843 | } | |
844 | ||
845 | static int copy_entries_to_user(unsigned int total_size, | |
846 | struct arpt_table *table, | |
847 | void __user *userptr) | |
848 | { | |
849 | unsigned int off, num, countersize; | |
850 | struct arpt_entry *e; | |
851 | struct arpt_counters *counters; | |
852 | int ret = 0; | |
31836064 | 853 | void *loc_cpu_entry; |
1da177e4 LT |
854 | |
855 | /* We need atomic snapshot of counters: rest doesn't change | |
856 | * (other than comefrom, which userspace doesn't care | |
857 | * about). | |
858 | */ | |
859 | countersize = sizeof(struct arpt_counters) * table->private->number; | |
860 | counters = vmalloc(countersize); | |
861 | ||
862 | if (counters == NULL) | |
863 | return -ENOMEM; | |
864 | ||
865 | /* First, sum counters... */ | |
1da177e4 LT |
866 | write_lock_bh(&table->lock); |
867 | get_counters(table->private, counters); | |
868 | write_unlock_bh(&table->lock); | |
869 | ||
31836064 ED |
870 | loc_cpu_entry = table->private->entries[raw_smp_processor_id()]; |
871 | /* ... then copy entire thing ... */ | |
872 | if (copy_to_user(userptr, loc_cpu_entry, total_size) != 0) { | |
1da177e4 LT |
873 | ret = -EFAULT; |
874 | goto free_counters; | |
875 | } | |
876 | ||
877 | /* FIXME: use iterator macros --RR */ | |
878 | /* ... then go back and fix counters and names */ | |
879 | for (off = 0, num = 0; off < total_size; off += e->next_offset, num++){ | |
880 | struct arpt_entry_target *t; | |
881 | ||
31836064 | 882 | e = (struct arpt_entry *)(loc_cpu_entry + off); |
1da177e4 LT |
883 | if (copy_to_user(userptr + off |
884 | + offsetof(struct arpt_entry, counters), | |
885 | &counters[num], | |
886 | sizeof(counters[num])) != 0) { | |
887 | ret = -EFAULT; | |
888 | goto free_counters; | |
889 | } | |
890 | ||
891 | t = arpt_get_target(e); | |
892 | if (copy_to_user(userptr + off + e->target_offset | |
893 | + offsetof(struct arpt_entry_target, | |
894 | u.user.name), | |
895 | t->u.kernel.target->name, | |
896 | strlen(t->u.kernel.target->name)+1) != 0) { | |
897 | ret = -EFAULT; | |
898 | goto free_counters; | |
899 | } | |
900 | } | |
901 | ||
902 | free_counters: | |
903 | vfree(counters); | |
904 | return ret; | |
905 | } | |
906 | ||
907 | static int get_entries(const struct arpt_get_entries *entries, | |
908 | struct arpt_get_entries __user *uptr) | |
909 | { | |
910 | int ret; | |
911 | struct arpt_table *t; | |
912 | ||
6b7d31fc HW |
913 | t = find_table_lock(entries->name); |
914 | if (t || !IS_ERR(t)) { | |
1da177e4 LT |
915 | duprintf("t->private->number = %u\n", |
916 | t->private->number); | |
917 | if (entries->size == t->private->size) | |
918 | ret = copy_entries_to_user(t->private->size, | |
919 | t, uptr->entrytable); | |
920 | else { | |
921 | duprintf("get_entries: I've got %u not %u!\n", | |
922 | t->private->size, | |
923 | entries->size); | |
924 | ret = -EINVAL; | |
925 | } | |
6b7d31fc | 926 | module_put(t->me); |
1da177e4 LT |
927 | up(&arpt_mutex); |
928 | } else | |
6b7d31fc | 929 | ret = t ? PTR_ERR(t) : -ENOENT; |
1da177e4 LT |
930 | |
931 | return ret; | |
932 | } | |
933 | ||
31836064 ED |
934 | static void free_table_info(struct arpt_table_info *info) |
935 | { | |
936 | int cpu; | |
937 | for_each_cpu(cpu) { | |
938 | if (info->size <= PAGE_SIZE) | |
939 | kfree(info->entries[cpu]); | |
940 | else | |
941 | vfree(info->entries[cpu]); | |
942 | } | |
943 | kfree(info); | |
944 | } | |
945 | ||
946 | static struct arpt_table_info *alloc_table_info(unsigned int size) | |
947 | { | |
948 | struct arpt_table_info *newinfo; | |
949 | int cpu; | |
950 | ||
951 | newinfo = kzalloc(sizeof(struct arpt_table_info), GFP_KERNEL); | |
952 | if (!newinfo) | |
953 | return NULL; | |
954 | ||
955 | newinfo->size = size; | |
956 | ||
957 | for_each_cpu(cpu) { | |
958 | if (size <= PAGE_SIZE) | |
959 | newinfo->entries[cpu] = kmalloc_node(size, | |
960 | GFP_KERNEL, | |
961 | cpu_to_node(cpu)); | |
962 | else | |
963 | newinfo->entries[cpu] = vmalloc_node(size, | |
964 | cpu_to_node(cpu)); | |
965 | ||
966 | if (newinfo->entries[cpu] == NULL) { | |
967 | free_table_info(newinfo); | |
968 | return NULL; | |
969 | } | |
970 | } | |
971 | ||
972 | return newinfo; | |
973 | } | |
974 | ||
1da177e4 LT |
975 | static int do_replace(void __user *user, unsigned int len) |
976 | { | |
977 | int ret; | |
978 | struct arpt_replace tmp; | |
979 | struct arpt_table *t; | |
980 | struct arpt_table_info *newinfo, *oldinfo; | |
981 | struct arpt_counters *counters; | |
31836064 | 982 | void *loc_cpu_entry, *loc_cpu_old_entry; |
1da177e4 LT |
983 | |
984 | if (copy_from_user(&tmp, user, sizeof(tmp)) != 0) | |
985 | return -EFAULT; | |
986 | ||
987 | /* Hack: Causes ipchains to give correct error msg --RR */ | |
988 | if (len != sizeof(tmp) + tmp.size) | |
989 | return -ENOPROTOOPT; | |
990 | ||
991 | /* Pedantry: prevent them from hitting BUG() in vmalloc.c --RR */ | |
992 | if ((SMP_ALIGN(tmp.size) >> PAGE_SHIFT) + 2 > num_physpages) | |
993 | return -ENOMEM; | |
994 | ||
31836064 | 995 | newinfo = alloc_table_info(tmp.size); |
1da177e4 LT |
996 | if (!newinfo) |
997 | return -ENOMEM; | |
998 | ||
31836064 ED |
999 | /* choose the copy that is on our node/cpu */ |
1000 | loc_cpu_entry = newinfo->entries[raw_smp_processor_id()]; | |
1001 | if (copy_from_user(loc_cpu_entry, user + sizeof(tmp), | |
1da177e4 LT |
1002 | tmp.size) != 0) { |
1003 | ret = -EFAULT; | |
1004 | goto free_newinfo; | |
1005 | } | |
1006 | ||
1007 | counters = vmalloc(tmp.num_counters * sizeof(struct arpt_counters)); | |
1008 | if (!counters) { | |
1009 | ret = -ENOMEM; | |
1010 | goto free_newinfo; | |
1011 | } | |
1da177e4 LT |
1012 | |
1013 | ret = translate_table(tmp.name, tmp.valid_hooks, | |
31836064 | 1014 | newinfo, loc_cpu_entry, tmp.size, tmp.num_entries, |
1da177e4 LT |
1015 | tmp.hook_entry, tmp.underflow); |
1016 | if (ret != 0) | |
1017 | goto free_newinfo_counters; | |
1018 | ||
1019 | duprintf("arp_tables: Translated table\n"); | |
1020 | ||
6b7d31fc HW |
1021 | t = try_then_request_module(find_table_lock(tmp.name), |
1022 | "arptable_%s", tmp.name); | |
1023 | if (!t || IS_ERR(t)) { | |
1024 | ret = t ? PTR_ERR(t) : -ENOENT; | |
1da177e4 | 1025 | goto free_newinfo_counters_untrans; |
6b7d31fc | 1026 | } |
1da177e4 LT |
1027 | |
1028 | /* You lied! */ | |
1029 | if (tmp.valid_hooks != t->valid_hooks) { | |
1030 | duprintf("Valid hook crap: %08X vs %08X\n", | |
1031 | tmp.valid_hooks, t->valid_hooks); | |
1032 | ret = -EINVAL; | |
6b7d31fc | 1033 | goto put_module; |
1da177e4 LT |
1034 | } |
1035 | ||
1036 | oldinfo = replace_table(t, tmp.num_counters, newinfo, &ret); | |
1037 | if (!oldinfo) | |
1038 | goto put_module; | |
1039 | ||
1040 | /* Update module usage count based on number of rules */ | |
1041 | duprintf("do_replace: oldnum=%u, initnum=%u, newnum=%u\n", | |
1042 | oldinfo->number, oldinfo->initial_entries, newinfo->number); | |
1043 | if ((oldinfo->number > oldinfo->initial_entries) || | |
1044 | (newinfo->number <= oldinfo->initial_entries)) | |
1045 | module_put(t->me); | |
1046 | if ((oldinfo->number > oldinfo->initial_entries) && | |
1047 | (newinfo->number <= oldinfo->initial_entries)) | |
1048 | module_put(t->me); | |
1049 | ||
1050 | /* Get the old counters. */ | |
1051 | get_counters(oldinfo, counters); | |
1052 | /* Decrease module usage counts and free resource */ | |
31836064 ED |
1053 | loc_cpu_old_entry = oldinfo->entries[raw_smp_processor_id()]; |
1054 | ARPT_ENTRY_ITERATE(loc_cpu_old_entry, oldinfo->size, cleanup_entry,NULL); | |
1055 | ||
1056 | free_table_info(oldinfo); | |
1da177e4 LT |
1057 | if (copy_to_user(tmp.counters, counters, |
1058 | sizeof(struct arpt_counters) * tmp.num_counters) != 0) | |
1059 | ret = -EFAULT; | |
1060 | vfree(counters); | |
1061 | up(&arpt_mutex); | |
1062 | return ret; | |
1063 | ||
1064 | put_module: | |
1065 | module_put(t->me); | |
1da177e4 LT |
1066 | up(&arpt_mutex); |
1067 | free_newinfo_counters_untrans: | |
31836064 | 1068 | ARPT_ENTRY_ITERATE(loc_cpu_entry, newinfo->size, cleanup_entry, NULL); |
1da177e4 LT |
1069 | free_newinfo_counters: |
1070 | vfree(counters); | |
1071 | free_newinfo: | |
31836064 | 1072 | free_table_info(newinfo); |
1da177e4 LT |
1073 | return ret; |
1074 | } | |
1075 | ||
1076 | /* We're lazy, and add to the first CPU; overflow works its fey magic | |
1077 | * and everything is OK. | |
1078 | */ | |
1079 | static inline int add_counter_to_entry(struct arpt_entry *e, | |
1080 | const struct arpt_counters addme[], | |
1081 | unsigned int *i) | |
1082 | { | |
1083 | ||
1084 | ADD_COUNTER(e->counters, addme[*i].bcnt, addme[*i].pcnt); | |
1085 | ||
1086 | (*i)++; | |
1087 | return 0; | |
1088 | } | |
1089 | ||
1090 | static int do_add_counters(void __user *user, unsigned int len) | |
1091 | { | |
1092 | unsigned int i; | |
1093 | struct arpt_counters_info tmp, *paddc; | |
1094 | struct arpt_table *t; | |
6b7d31fc | 1095 | int ret = 0; |
31836064 | 1096 | void *loc_cpu_entry; |
1da177e4 LT |
1097 | |
1098 | if (copy_from_user(&tmp, user, sizeof(tmp)) != 0) | |
1099 | return -EFAULT; | |
1100 | ||
1101 | if (len != sizeof(tmp) + tmp.num_counters*sizeof(struct arpt_counters)) | |
1102 | return -EINVAL; | |
1103 | ||
1104 | paddc = vmalloc(len); | |
1105 | if (!paddc) | |
1106 | return -ENOMEM; | |
1107 | ||
1108 | if (copy_from_user(paddc, user, len) != 0) { | |
1109 | ret = -EFAULT; | |
1110 | goto free; | |
1111 | } | |
1112 | ||
6b7d31fc HW |
1113 | t = find_table_lock(tmp.name); |
1114 | if (!t || IS_ERR(t)) { | |
1115 | ret = t ? PTR_ERR(t) : -ENOENT; | |
1da177e4 | 1116 | goto free; |
6b7d31fc | 1117 | } |
1da177e4 LT |
1118 | |
1119 | write_lock_bh(&t->lock); | |
1120 | if (t->private->number != paddc->num_counters) { | |
1121 | ret = -EINVAL; | |
1122 | goto unlock_up_free; | |
1123 | } | |
1124 | ||
1125 | i = 0; | |
31836064 ED |
1126 | /* Choose the copy that is on our node */ |
1127 | loc_cpu_entry = t->private->entries[smp_processor_id()]; | |
1128 | ARPT_ENTRY_ITERATE(loc_cpu_entry, | |
1da177e4 LT |
1129 | t->private->size, |
1130 | add_counter_to_entry, | |
1131 | paddc->counters, | |
1132 | &i); | |
1133 | unlock_up_free: | |
1134 | write_unlock_bh(&t->lock); | |
1135 | up(&arpt_mutex); | |
6b7d31fc | 1136 | module_put(t->me); |
1da177e4 LT |
1137 | free: |
1138 | vfree(paddc); | |
1139 | ||
1140 | return ret; | |
1141 | } | |
1142 | ||
1143 | static int do_arpt_set_ctl(struct sock *sk, int cmd, void __user *user, unsigned int len) | |
1144 | { | |
1145 | int ret; | |
1146 | ||
1147 | if (!capable(CAP_NET_ADMIN)) | |
1148 | return -EPERM; | |
1149 | ||
1150 | switch (cmd) { | |
1151 | case ARPT_SO_SET_REPLACE: | |
1152 | ret = do_replace(user, len); | |
1153 | break; | |
1154 | ||
1155 | case ARPT_SO_SET_ADD_COUNTERS: | |
1156 | ret = do_add_counters(user, len); | |
1157 | break; | |
1158 | ||
1159 | default: | |
1160 | duprintf("do_arpt_set_ctl: unknown request %i\n", cmd); | |
1161 | ret = -EINVAL; | |
1162 | } | |
1163 | ||
1164 | return ret; | |
1165 | } | |
1166 | ||
1167 | static int do_arpt_get_ctl(struct sock *sk, int cmd, void __user *user, int *len) | |
1168 | { | |
1169 | int ret; | |
1170 | ||
1171 | if (!capable(CAP_NET_ADMIN)) | |
1172 | return -EPERM; | |
1173 | ||
1174 | switch (cmd) { | |
1175 | case ARPT_SO_GET_INFO: { | |
1176 | char name[ARPT_TABLE_MAXNAMELEN]; | |
1177 | struct arpt_table *t; | |
1178 | ||
1179 | if (*len != sizeof(struct arpt_getinfo)) { | |
1180 | duprintf("length %u != %Zu\n", *len, | |
1181 | sizeof(struct arpt_getinfo)); | |
1182 | ret = -EINVAL; | |
1183 | break; | |
1184 | } | |
1185 | ||
1186 | if (copy_from_user(name, user, sizeof(name)) != 0) { | |
1187 | ret = -EFAULT; | |
1188 | break; | |
1189 | } | |
1190 | name[ARPT_TABLE_MAXNAMELEN-1] = '\0'; | |
6b7d31fc HW |
1191 | |
1192 | t = try_then_request_module(find_table_lock(name), | |
1193 | "arptable_%s", name); | |
1194 | if (t && !IS_ERR(t)) { | |
1da177e4 LT |
1195 | struct arpt_getinfo info; |
1196 | ||
1197 | info.valid_hooks = t->valid_hooks; | |
1198 | memcpy(info.hook_entry, t->private->hook_entry, | |
1199 | sizeof(info.hook_entry)); | |
1200 | memcpy(info.underflow, t->private->underflow, | |
1201 | sizeof(info.underflow)); | |
1202 | info.num_entries = t->private->number; | |
1203 | info.size = t->private->size; | |
1204 | strcpy(info.name, name); | |
1205 | ||
1206 | if (copy_to_user(user, &info, *len) != 0) | |
1207 | ret = -EFAULT; | |
1208 | else | |
1209 | ret = 0; | |
1da177e4 | 1210 | up(&arpt_mutex); |
6b7d31fc HW |
1211 | module_put(t->me); |
1212 | } else | |
1213 | ret = t ? PTR_ERR(t) : -ENOENT; | |
1da177e4 LT |
1214 | } |
1215 | break; | |
1216 | ||
1217 | case ARPT_SO_GET_ENTRIES: { | |
1218 | struct arpt_get_entries get; | |
1219 | ||
1220 | if (*len < sizeof(get)) { | |
1221 | duprintf("get_entries: %u < %Zu\n", *len, sizeof(get)); | |
1222 | ret = -EINVAL; | |
1223 | } else if (copy_from_user(&get, user, sizeof(get)) != 0) { | |
1224 | ret = -EFAULT; | |
1225 | } else if (*len != sizeof(struct arpt_get_entries) + get.size) { | |
1226 | duprintf("get_entries: %u != %Zu\n", *len, | |
1227 | sizeof(struct arpt_get_entries) + get.size); | |
1228 | ret = -EINVAL; | |
1229 | } else | |
1230 | ret = get_entries(&get, user); | |
1231 | break; | |
1232 | } | |
1233 | ||
6b7d31fc HW |
1234 | case ARPT_SO_GET_REVISION_TARGET: { |
1235 | struct arpt_get_revision rev; | |
1236 | ||
1237 | if (*len != sizeof(rev)) { | |
1238 | ret = -EINVAL; | |
1239 | break; | |
1240 | } | |
1241 | if (copy_from_user(&rev, user, sizeof(rev)) != 0) { | |
1242 | ret = -EFAULT; | |
1243 | break; | |
1244 | } | |
1245 | ||
1246 | try_then_request_module(find_revision(rev.name, rev.revision, | |
1247 | target_revfn, &ret), | |
1248 | "arpt_%s", rev.name); | |
1249 | break; | |
1250 | } | |
1251 | ||
1da177e4 LT |
1252 | default: |
1253 | duprintf("do_arpt_get_ctl: unknown request %i\n", cmd); | |
1254 | ret = -EINVAL; | |
1255 | } | |
1256 | ||
1257 | return ret; | |
1258 | } | |
1259 | ||
1260 | /* Registration hooks for targets. */ | |
1261 | int arpt_register_target(struct arpt_target *target) | |
1262 | { | |
1263 | int ret; | |
1264 | ||
1265 | ret = down_interruptible(&arpt_mutex); | |
1266 | if (ret != 0) | |
1267 | return ret; | |
1268 | ||
6b7d31fc | 1269 | list_add(&target->list, &arpt_target); |
1da177e4 | 1270 | up(&arpt_mutex); |
6b7d31fc | 1271 | |
1da177e4 LT |
1272 | return ret; |
1273 | } | |
1274 | ||
1275 | void arpt_unregister_target(struct arpt_target *target) | |
1276 | { | |
1277 | down(&arpt_mutex); | |
1278 | LIST_DELETE(&arpt_target, target); | |
1279 | up(&arpt_mutex); | |
1280 | } | |
1281 | ||
1282 | int arpt_register_table(struct arpt_table *table, | |
1283 | const struct arpt_replace *repl) | |
1284 | { | |
1285 | int ret; | |
1286 | struct arpt_table_info *newinfo; | |
1287 | static struct arpt_table_info bootstrap | |
1288 | = { 0, 0, 0, { 0 }, { 0 }, { } }; | |
31836064 | 1289 | void *loc_cpu_entry; |
1da177e4 | 1290 | |
31836064 | 1291 | newinfo = alloc_table_info(repl->size); |
1da177e4 LT |
1292 | if (!newinfo) { |
1293 | ret = -ENOMEM; | |
1294 | return ret; | |
1295 | } | |
31836064 ED |
1296 | |
1297 | /* choose the copy on our node/cpu */ | |
1298 | loc_cpu_entry = newinfo->entries[raw_smp_processor_id()]; | |
1299 | memcpy(loc_cpu_entry, repl->entries, repl->size); | |
1da177e4 LT |
1300 | |
1301 | ret = translate_table(table->name, table->valid_hooks, | |
31836064 | 1302 | newinfo, loc_cpu_entry, repl->size, |
1da177e4 LT |
1303 | repl->num_entries, |
1304 | repl->hook_entry, | |
1305 | repl->underflow); | |
1306 | duprintf("arpt_register_table: translate table gives %d\n", ret); | |
1307 | if (ret != 0) { | |
31836064 | 1308 | free_table_info(newinfo); |
1da177e4 LT |
1309 | return ret; |
1310 | } | |
1311 | ||
1312 | ret = down_interruptible(&arpt_mutex); | |
1313 | if (ret != 0) { | |
31836064 | 1314 | free_table_info(newinfo); |
1da177e4 LT |
1315 | return ret; |
1316 | } | |
1317 | ||
1318 | /* Don't autoload: we'd eat our tail... */ | |
1319 | if (list_named_find(&arpt_tables, table->name)) { | |
1320 | ret = -EEXIST; | |
1321 | goto free_unlock; | |
1322 | } | |
1323 | ||
1324 | /* Simplifies replace_table code. */ | |
1325 | table->private = &bootstrap; | |
1326 | if (!replace_table(table, 0, newinfo, &ret)) | |
1327 | goto free_unlock; | |
1328 | ||
1329 | duprintf("table->private->number = %u\n", | |
1330 | table->private->number); | |
1331 | ||
1332 | /* save number of initial entries */ | |
1333 | table->private->initial_entries = table->private->number; | |
1334 | ||
1335 | rwlock_init(&table->lock); | |
1336 | list_prepend(&arpt_tables, table); | |
1337 | ||
1338 | unlock: | |
1339 | up(&arpt_mutex); | |
1340 | return ret; | |
1341 | ||
1342 | free_unlock: | |
31836064 | 1343 | free_table_info(newinfo); |
1da177e4 LT |
1344 | goto unlock; |
1345 | } | |
1346 | ||
1347 | void arpt_unregister_table(struct arpt_table *table) | |
1348 | { | |
31836064 ED |
1349 | void *loc_cpu_entry; |
1350 | ||
1da177e4 LT |
1351 | down(&arpt_mutex); |
1352 | LIST_DELETE(&arpt_tables, table); | |
1353 | up(&arpt_mutex); | |
1354 | ||
1355 | /* Decrease module usage counts and free resources */ | |
31836064 ED |
1356 | loc_cpu_entry = table->private->entries[raw_smp_processor_id()]; |
1357 | ARPT_ENTRY_ITERATE(loc_cpu_entry, table->private->size, | |
1da177e4 | 1358 | cleanup_entry, NULL); |
31836064 | 1359 | free_table_info(table->private); |
1da177e4 LT |
1360 | } |
1361 | ||
1362 | /* The built-in targets: standard (NULL) and error. */ | |
1363 | static struct arpt_target arpt_standard_target = { | |
1364 | .name = ARPT_STANDARD_TARGET, | |
1365 | }; | |
1366 | ||
1367 | static struct arpt_target arpt_error_target = { | |
1368 | .name = ARPT_ERROR_TARGET, | |
1369 | .target = arpt_error, | |
1370 | }; | |
1371 | ||
1372 | static struct nf_sockopt_ops arpt_sockopts = { | |
1373 | .pf = PF_INET, | |
1374 | .set_optmin = ARPT_BASE_CTL, | |
1375 | .set_optmax = ARPT_SO_SET_MAX+1, | |
1376 | .set = do_arpt_set_ctl, | |
1377 | .get_optmin = ARPT_BASE_CTL, | |
1378 | .get_optmax = ARPT_SO_GET_MAX+1, | |
1379 | .get = do_arpt_get_ctl, | |
1380 | }; | |
1381 | ||
1382 | #ifdef CONFIG_PROC_FS | |
1383 | static inline int print_name(const struct arpt_table *t, | |
1384 | off_t start_offset, char *buffer, int length, | |
1385 | off_t *pos, unsigned int *count) | |
1386 | { | |
1387 | if ((*count)++ >= start_offset) { | |
1388 | unsigned int namelen; | |
1389 | ||
1390 | namelen = sprintf(buffer + *pos, "%s\n", t->name); | |
1391 | if (*pos + namelen > length) { | |
1392 | /* Stop iterating */ | |
1393 | return 1; | |
1394 | } | |
1395 | *pos += namelen; | |
1396 | } | |
1397 | return 0; | |
1398 | } | |
1399 | ||
1400 | static int arpt_get_tables(char *buffer, char **start, off_t offset, int length) | |
1401 | { | |
1402 | off_t pos = 0; | |
1403 | unsigned int count = 0; | |
1404 | ||
1405 | if (down_interruptible(&arpt_mutex) != 0) | |
1406 | return 0; | |
1407 | ||
1408 | LIST_FIND(&arpt_tables, print_name, struct arpt_table *, | |
1409 | offset, buffer, length, &pos, &count); | |
1410 | ||
1411 | up(&arpt_mutex); | |
1412 | ||
1413 | /* `start' hack - see fs/proc/generic.c line ~105 */ | |
1414 | *start=(char *)((unsigned long)count-offset); | |
1415 | return pos; | |
1416 | } | |
1417 | #endif /*CONFIG_PROC_FS*/ | |
1418 | ||
1419 | static int __init init(void) | |
1420 | { | |
1421 | int ret; | |
1422 | ||
1423 | /* Noone else will be downing sem now, so we won't sleep */ | |
1424 | down(&arpt_mutex); | |
1425 | list_append(&arpt_target, &arpt_standard_target); | |
1426 | list_append(&arpt_target, &arpt_error_target); | |
1427 | up(&arpt_mutex); | |
1428 | ||
1429 | /* Register setsockopt */ | |
1430 | ret = nf_register_sockopt(&arpt_sockopts); | |
1431 | if (ret < 0) { | |
1432 | duprintf("Unable to register sockopts.\n"); | |
1433 | return ret; | |
1434 | } | |
1435 | ||
1436 | #ifdef CONFIG_PROC_FS | |
1437 | { | |
1438 | struct proc_dir_entry *proc; | |
1439 | ||
1440 | proc = proc_net_create("arp_tables_names", 0, arpt_get_tables); | |
1441 | if (!proc) { | |
1442 | nf_unregister_sockopt(&arpt_sockopts); | |
1443 | return -ENOMEM; | |
1444 | } | |
1445 | proc->owner = THIS_MODULE; | |
1446 | } | |
1447 | #endif | |
1448 | ||
1449 | printk("arp_tables: (C) 2002 David S. Miller\n"); | |
1450 | return 0; | |
1451 | } | |
1452 | ||
1453 | static void __exit fini(void) | |
1454 | { | |
1455 | nf_unregister_sockopt(&arpt_sockopts); | |
1456 | #ifdef CONFIG_PROC_FS | |
1457 | proc_net_remove("arp_tables_names"); | |
1458 | #endif | |
1459 | } | |
1460 | ||
1461 | EXPORT_SYMBOL(arpt_register_table); | |
1462 | EXPORT_SYMBOL(arpt_unregister_table); | |
1463 | EXPORT_SYMBOL(arpt_do_table); | |
1464 | EXPORT_SYMBOL(arpt_register_target); | |
1465 | EXPORT_SYMBOL(arpt_unregister_target); | |
1466 | ||
1467 | module_init(init); | |
1468 | module_exit(fini); |