Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * ebtables |
| 3 | * |
| 4 | * Author: |
| 5 | * Bart De Schuymer <bdschuym@pandora.be> |
| 6 | * |
| 7 | * ebtables.c,v 2.0, July, 2002 |
| 8 | * |
| 9 | * This code is stongly inspired on the iptables code which is |
| 10 | * Copyright (C) 1999 Paul `Rusty' Russell & Michael J. Neuling |
| 11 | * |
| 12 | * This program is free software; you can redistribute it and/or |
| 13 | * modify it under the terms of the GNU General Public License |
| 14 | * as published by the Free Software Foundation; either version |
| 15 | * 2 of the License, or (at your option) any later version. |
| 16 | */ |
| 17 | |
| 18 | /* used for print_string */ |
| 19 | #include <linux/sched.h> |
| 20 | #include <linux/tty.h> |
| 21 | |
| 22 | #include <linux/kmod.h> |
| 23 | #include <linux/module.h> |
| 24 | #include <linux/vmalloc.h> |
| 25 | #include <linux/netfilter_bridge/ebtables.h> |
| 26 | #include <linux/spinlock.h> |
Patrick McHardy | df0933d | 2006-09-20 11:57:53 -0700 | [diff] [blame] | 27 | #include <linux/mutex.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 28 | #include <asm/uaccess.h> |
| 29 | #include <linux/smp.h> |
David S. Miller | c8923c6 | 2005-10-13 14:41:23 -0700 | [diff] [blame] | 30 | #include <linux/cpumask.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 31 | #include <net/sock.h> |
| 32 | /* needed for logical [in,out]-dev filtering */ |
| 33 | #include "../br_private.h" |
| 34 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 35 | #define BUGPRINT(format, args...) printk("kernel msg: ebtables bug: please "\ |
| 36 | "report to author: "format, ## args) |
| 37 | /* #define BUGPRINT(format, args...) */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 38 | #define MEMPRINT(format, args...) printk("kernel msg: ebtables "\ |
| 39 | ": out of memory: "format, ## args) |
| 40 | /* #define MEMPRINT(format, args...) */ |
| 41 | |
| 42 | |
| 43 | |
| 44 | /* |
| 45 | * Each cpu has its own set of counters, so there is no need for write_lock in |
| 46 | * the softirq |
| 47 | * For reading or updating the counters, the user context needs to |
| 48 | * get a write_lock |
| 49 | */ |
| 50 | |
| 51 | /* The size of each set of counters is altered to get cache alignment */ |
| 52 | #define SMP_ALIGN(x) (((x) + SMP_CACHE_BYTES-1) & ~(SMP_CACHE_BYTES-1)) |
| 53 | #define COUNTER_OFFSET(n) (SMP_ALIGN(n * sizeof(struct ebt_counter))) |
| 54 | #define COUNTER_BASE(c, n, cpu) ((struct ebt_counter *)(((char *)c) + \ |
| 55 | COUNTER_OFFSET(n) * cpu)) |
| 56 | |
| 57 | |
| 58 | |
Ingo Molnar | 57b47a5 | 2006-03-20 22:35:41 -0800 | [diff] [blame] | 59 | static DEFINE_MUTEX(ebt_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 60 | static LIST_HEAD(ebt_tables); |
| 61 | static LIST_HEAD(ebt_targets); |
| 62 | static LIST_HEAD(ebt_matches); |
| 63 | static LIST_HEAD(ebt_watchers); |
| 64 | |
| 65 | static struct ebt_target ebt_standard_target = |
| 66 | { {NULL, NULL}, EBT_STANDARD_TARGET, NULL, NULL, NULL, NULL}; |
| 67 | |
| 68 | static inline int ebt_do_watcher (struct ebt_entry_watcher *w, |
| 69 | const struct sk_buff *skb, unsigned int hooknr, const struct net_device *in, |
| 70 | const struct net_device *out) |
| 71 | { |
| 72 | w->u.watcher->watcher(skb, hooknr, in, out, w->data, |
| 73 | w->watcher_size); |
| 74 | /* watchers don't give a verdict */ |
| 75 | return 0; |
| 76 | } |
| 77 | |
| 78 | static inline int ebt_do_match (struct ebt_entry_match *m, |
| 79 | const struct sk_buff *skb, const struct net_device *in, |
| 80 | const struct net_device *out) |
| 81 | { |
| 82 | return m->u.match->match(skb, in, out, m->data, |
| 83 | m->match_size); |
| 84 | } |
| 85 | |
| 86 | static inline int ebt_dev_check(char *entry, const struct net_device *device) |
| 87 | { |
| 88 | int i = 0; |
Meelis Roos | 6f5b7ef | 2006-11-01 18:07:27 -0800 | [diff] [blame] | 89 | const char *devname = device->name; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 90 | |
| 91 | if (*entry == '\0') |
| 92 | return 0; |
| 93 | if (!device) |
| 94 | return 1; |
| 95 | /* 1 is the wildcard token */ |
| 96 | while (entry[i] != '\0' && entry[i] != 1 && entry[i] == devname[i]) |
| 97 | i++; |
| 98 | return (devname[i] != entry[i] && entry[i] != 1); |
| 99 | } |
| 100 | |
| 101 | #define FWINV2(bool,invflg) ((bool) ^ !!(e->invflags & invflg)) |
| 102 | /* process standard matches */ |
| 103 | static inline int ebt_basic_match(struct ebt_entry *e, struct ethhdr *h, |
| 104 | const struct net_device *in, const struct net_device *out) |
| 105 | { |
| 106 | int verdict, i; |
| 107 | |
| 108 | if (e->bitmask & EBT_802_3) { |
| 109 | if (FWINV2(ntohs(h->h_proto) >= 1536, EBT_IPROTO)) |
| 110 | return 1; |
| 111 | } else if (!(e->bitmask & EBT_NOPROTO) && |
| 112 | FWINV2(e->ethproto != h->h_proto, EBT_IPROTO)) |
| 113 | return 1; |
| 114 | |
| 115 | if (FWINV2(ebt_dev_check(e->in, in), EBT_IIN)) |
| 116 | return 1; |
| 117 | if (FWINV2(ebt_dev_check(e->out, out), EBT_IOUT)) |
| 118 | return 1; |
| 119 | if ((!in || !in->br_port) ? 0 : FWINV2(ebt_dev_check( |
| 120 | e->logical_in, in->br_port->br->dev), EBT_ILOGICALIN)) |
| 121 | return 1; |
| 122 | if ((!out || !out->br_port) ? 0 : FWINV2(ebt_dev_check( |
| 123 | e->logical_out, out->br_port->br->dev), EBT_ILOGICALOUT)) |
| 124 | return 1; |
| 125 | |
| 126 | if (e->bitmask & EBT_SOURCEMAC) { |
| 127 | verdict = 0; |
| 128 | for (i = 0; i < 6; i++) |
| 129 | verdict |= (h->h_source[i] ^ e->sourcemac[i]) & |
| 130 | e->sourcemsk[i]; |
| 131 | if (FWINV2(verdict != 0, EBT_ISOURCE) ) |
| 132 | return 1; |
| 133 | } |
| 134 | if (e->bitmask & EBT_DESTMAC) { |
| 135 | verdict = 0; |
| 136 | for (i = 0; i < 6; i++) |
| 137 | verdict |= (h->h_dest[i] ^ e->destmac[i]) & |
| 138 | e->destmsk[i]; |
| 139 | if (FWINV2(verdict != 0, EBT_IDEST) ) |
| 140 | return 1; |
| 141 | } |
| 142 | return 0; |
| 143 | } |
| 144 | |
| 145 | /* Do some firewalling */ |
| 146 | unsigned int ebt_do_table (unsigned int hook, struct sk_buff **pskb, |
| 147 | const struct net_device *in, const struct net_device *out, |
| 148 | struct ebt_table *table) |
| 149 | { |
| 150 | int i, nentries; |
| 151 | struct ebt_entry *point; |
| 152 | struct ebt_counter *counter_base, *cb_base; |
| 153 | struct ebt_entry_target *t; |
| 154 | int verdict, sp = 0; |
| 155 | struct ebt_chainstack *cs; |
| 156 | struct ebt_entries *chaininfo; |
| 157 | char *base; |
| 158 | struct ebt_table_info *private; |
| 159 | |
| 160 | read_lock_bh(&table->lock); |
| 161 | private = table->private; |
| 162 | cb_base = COUNTER_BASE(private->counters, private->nentries, |
| 163 | smp_processor_id()); |
| 164 | if (private->chainstack) |
| 165 | cs = private->chainstack[smp_processor_id()]; |
| 166 | else |
| 167 | cs = NULL; |
| 168 | chaininfo = private->hook_entry[hook]; |
| 169 | nentries = private->hook_entry[hook]->nentries; |
| 170 | point = (struct ebt_entry *)(private->hook_entry[hook]->data); |
| 171 | counter_base = cb_base + private->hook_entry[hook]->counter_offset; |
| 172 | /* base for chain jumps */ |
| 173 | base = private->entries; |
| 174 | i = 0; |
| 175 | while (i < nentries) { |
| 176 | if (ebt_basic_match(point, eth_hdr(*pskb), in, out)) |
| 177 | goto letscontinue; |
| 178 | |
| 179 | if (EBT_MATCH_ITERATE(point, ebt_do_match, *pskb, in, out) != 0) |
| 180 | goto letscontinue; |
| 181 | |
| 182 | /* increase counter */ |
| 183 | (*(counter_base + i)).pcnt++; |
| 184 | (*(counter_base + i)).bcnt+=(**pskb).len; |
| 185 | |
| 186 | /* these should only watch: not modify, nor tell us |
| 187 | what to do with the packet */ |
| 188 | EBT_WATCHER_ITERATE(point, ebt_do_watcher, *pskb, hook, in, |
| 189 | out); |
| 190 | |
| 191 | t = (struct ebt_entry_target *) |
| 192 | (((char *)point) + point->target_offset); |
| 193 | /* standard target */ |
| 194 | if (!t->u.target->target) |
| 195 | verdict = ((struct ebt_standard_target *)t)->verdict; |
| 196 | else |
| 197 | verdict = t->u.target->target(pskb, hook, |
| 198 | in, out, t->data, t->target_size); |
| 199 | if (verdict == EBT_ACCEPT) { |
| 200 | read_unlock_bh(&table->lock); |
| 201 | return NF_ACCEPT; |
| 202 | } |
| 203 | if (verdict == EBT_DROP) { |
| 204 | read_unlock_bh(&table->lock); |
| 205 | return NF_DROP; |
| 206 | } |
| 207 | if (verdict == EBT_RETURN) { |
| 208 | letsreturn: |
| 209 | #ifdef CONFIG_NETFILTER_DEBUG |
| 210 | if (sp == 0) { |
| 211 | BUGPRINT("RETURN on base chain"); |
| 212 | /* act like this is EBT_CONTINUE */ |
| 213 | goto letscontinue; |
| 214 | } |
| 215 | #endif |
| 216 | sp--; |
| 217 | /* put all the local variables right */ |
| 218 | i = cs[sp].n; |
| 219 | chaininfo = cs[sp].chaininfo; |
| 220 | nentries = chaininfo->nentries; |
| 221 | point = cs[sp].e; |
| 222 | counter_base = cb_base + |
| 223 | chaininfo->counter_offset; |
| 224 | continue; |
| 225 | } |
| 226 | if (verdict == EBT_CONTINUE) |
| 227 | goto letscontinue; |
| 228 | #ifdef CONFIG_NETFILTER_DEBUG |
| 229 | if (verdict < 0) { |
| 230 | BUGPRINT("bogus standard verdict\n"); |
| 231 | read_unlock_bh(&table->lock); |
| 232 | return NF_DROP; |
| 233 | } |
| 234 | #endif |
| 235 | /* jump to a udc */ |
| 236 | cs[sp].n = i + 1; |
| 237 | cs[sp].chaininfo = chaininfo; |
| 238 | cs[sp].e = (struct ebt_entry *) |
| 239 | (((char *)point) + point->next_offset); |
| 240 | i = 0; |
| 241 | chaininfo = (struct ebt_entries *) (base + verdict); |
| 242 | #ifdef CONFIG_NETFILTER_DEBUG |
| 243 | if (chaininfo->distinguisher) { |
| 244 | BUGPRINT("jump to non-chain\n"); |
| 245 | read_unlock_bh(&table->lock); |
| 246 | return NF_DROP; |
| 247 | } |
| 248 | #endif |
| 249 | nentries = chaininfo->nentries; |
| 250 | point = (struct ebt_entry *)chaininfo->data; |
| 251 | counter_base = cb_base + chaininfo->counter_offset; |
| 252 | sp++; |
| 253 | continue; |
| 254 | letscontinue: |
| 255 | point = (struct ebt_entry *) |
| 256 | (((char *)point) + point->next_offset); |
| 257 | i++; |
| 258 | } |
| 259 | |
| 260 | /* I actually like this :) */ |
| 261 | if (chaininfo->policy == EBT_RETURN) |
| 262 | goto letsreturn; |
| 263 | if (chaininfo->policy == EBT_ACCEPT) { |
| 264 | read_unlock_bh(&table->lock); |
| 265 | return NF_ACCEPT; |
| 266 | } |
| 267 | read_unlock_bh(&table->lock); |
| 268 | return NF_DROP; |
| 269 | } |
| 270 | |
| 271 | /* If it succeeds, returns element and locks mutex */ |
| 272 | static inline void * |
| 273 | find_inlist_lock_noload(struct list_head *head, const char *name, int *error, |
Ingo Molnar | 57b47a5 | 2006-03-20 22:35:41 -0800 | [diff] [blame] | 274 | struct mutex *mutex) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 275 | { |
Patrick McHardy | df0933d | 2006-09-20 11:57:53 -0700 | [diff] [blame] | 276 | struct { |
| 277 | struct list_head list; |
| 278 | char name[EBT_FUNCTION_MAXNAMELEN]; |
| 279 | } *e; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 280 | |
Ingo Molnar | 57b47a5 | 2006-03-20 22:35:41 -0800 | [diff] [blame] | 281 | *error = mutex_lock_interruptible(mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 282 | if (*error != 0) |
| 283 | return NULL; |
| 284 | |
Patrick McHardy | df0933d | 2006-09-20 11:57:53 -0700 | [diff] [blame] | 285 | list_for_each_entry(e, head, list) { |
| 286 | if (strcmp(e->name, name) == 0) |
| 287 | return e; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 288 | } |
Patrick McHardy | df0933d | 2006-09-20 11:57:53 -0700 | [diff] [blame] | 289 | *error = -ENOENT; |
| 290 | mutex_unlock(mutex); |
| 291 | return NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 292 | } |
| 293 | |
| 294 | #ifndef CONFIG_KMOD |
| 295 | #define find_inlist_lock(h,n,p,e,m) find_inlist_lock_noload((h),(n),(e),(m)) |
| 296 | #else |
| 297 | static void * |
| 298 | find_inlist_lock(struct list_head *head, const char *name, const char *prefix, |
Ingo Molnar | 57b47a5 | 2006-03-20 22:35:41 -0800 | [diff] [blame] | 299 | int *error, struct mutex *mutex) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 300 | { |
| 301 | void *ret; |
| 302 | |
| 303 | ret = find_inlist_lock_noload(head, name, error, mutex); |
| 304 | if (!ret) { |
| 305 | request_module("%s%s", prefix, name); |
| 306 | ret = find_inlist_lock_noload(head, name, error, mutex); |
| 307 | } |
| 308 | return ret; |
| 309 | } |
| 310 | #endif |
| 311 | |
| 312 | static inline struct ebt_table * |
Ingo Molnar | 57b47a5 | 2006-03-20 22:35:41 -0800 | [diff] [blame] | 313 | find_table_lock(const char *name, int *error, struct mutex *mutex) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 314 | { |
| 315 | return find_inlist_lock(&ebt_tables, name, "ebtable_", error, mutex); |
| 316 | } |
| 317 | |
| 318 | static inline struct ebt_match * |
Ingo Molnar | 57b47a5 | 2006-03-20 22:35:41 -0800 | [diff] [blame] | 319 | find_match_lock(const char *name, int *error, struct mutex *mutex) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 320 | { |
| 321 | return find_inlist_lock(&ebt_matches, name, "ebt_", error, mutex); |
| 322 | } |
| 323 | |
| 324 | static inline struct ebt_watcher * |
Ingo Molnar | 57b47a5 | 2006-03-20 22:35:41 -0800 | [diff] [blame] | 325 | find_watcher_lock(const char *name, int *error, struct mutex *mutex) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 326 | { |
| 327 | return find_inlist_lock(&ebt_watchers, name, "ebt_", error, mutex); |
| 328 | } |
| 329 | |
| 330 | static inline struct ebt_target * |
Ingo Molnar | 57b47a5 | 2006-03-20 22:35:41 -0800 | [diff] [blame] | 331 | find_target_lock(const char *name, int *error, struct mutex *mutex) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 332 | { |
| 333 | return find_inlist_lock(&ebt_targets, name, "ebt_", error, mutex); |
| 334 | } |
| 335 | |
| 336 | static inline int |
| 337 | ebt_check_match(struct ebt_entry_match *m, struct ebt_entry *e, |
| 338 | const char *name, unsigned int hookmask, unsigned int *cnt) |
| 339 | { |
| 340 | struct ebt_match *match; |
Al Viro | 14197d5 | 2006-11-30 19:25:21 -0800 | [diff] [blame] | 341 | size_t left = ((char *)e + e->watchers_offset) - (char *)m; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 342 | int ret; |
| 343 | |
Al Viro | 14197d5 | 2006-11-30 19:25:21 -0800 | [diff] [blame] | 344 | if (left < sizeof(struct ebt_entry_match) || |
| 345 | left - sizeof(struct ebt_entry_match) < m->match_size) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 346 | return -EINVAL; |
| 347 | match = find_match_lock(m->u.name, &ret, &ebt_mutex); |
| 348 | if (!match) |
| 349 | return ret; |
| 350 | m->u.match = match; |
| 351 | if (!try_module_get(match->me)) { |
Ingo Molnar | 57b47a5 | 2006-03-20 22:35:41 -0800 | [diff] [blame] | 352 | mutex_unlock(&ebt_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 353 | return -ENOENT; |
| 354 | } |
Ingo Molnar | 57b47a5 | 2006-03-20 22:35:41 -0800 | [diff] [blame] | 355 | mutex_unlock(&ebt_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 356 | if (match->check && |
| 357 | match->check(name, hookmask, e, m->data, m->match_size) != 0) { |
| 358 | BUGPRINT("match->check failed\n"); |
| 359 | module_put(match->me); |
| 360 | return -EINVAL; |
| 361 | } |
| 362 | (*cnt)++; |
| 363 | return 0; |
| 364 | } |
| 365 | |
| 366 | static inline int |
| 367 | ebt_check_watcher(struct ebt_entry_watcher *w, struct ebt_entry *e, |
| 368 | const char *name, unsigned int hookmask, unsigned int *cnt) |
| 369 | { |
| 370 | struct ebt_watcher *watcher; |
Al Viro | 14197d5 | 2006-11-30 19:25:21 -0800 | [diff] [blame] | 371 | size_t left = ((char *)e + e->target_offset) - (char *)w; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 372 | int ret; |
| 373 | |
Al Viro | 14197d5 | 2006-11-30 19:25:21 -0800 | [diff] [blame] | 374 | if (left < sizeof(struct ebt_entry_watcher) || |
| 375 | left - sizeof(struct ebt_entry_watcher) < w->watcher_size) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 376 | return -EINVAL; |
| 377 | watcher = find_watcher_lock(w->u.name, &ret, &ebt_mutex); |
| 378 | if (!watcher) |
| 379 | return ret; |
| 380 | w->u.watcher = watcher; |
| 381 | if (!try_module_get(watcher->me)) { |
Ingo Molnar | 57b47a5 | 2006-03-20 22:35:41 -0800 | [diff] [blame] | 382 | mutex_unlock(&ebt_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 383 | return -ENOENT; |
| 384 | } |
Ingo Molnar | 57b47a5 | 2006-03-20 22:35:41 -0800 | [diff] [blame] | 385 | mutex_unlock(&ebt_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 386 | if (watcher->check && |
| 387 | watcher->check(name, hookmask, e, w->data, w->watcher_size) != 0) { |
| 388 | BUGPRINT("watcher->check failed\n"); |
| 389 | module_put(watcher->me); |
| 390 | return -EINVAL; |
| 391 | } |
| 392 | (*cnt)++; |
| 393 | return 0; |
| 394 | } |
| 395 | |
Al Viro | 70fe9af | 2006-11-30 19:26:14 -0800 | [diff] [blame] | 396 | static int ebt_verify_pointers(struct ebt_replace *repl, |
| 397 | struct ebt_table_info *newinfo) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 398 | { |
Al Viro | 70fe9af | 2006-11-30 19:26:14 -0800 | [diff] [blame] | 399 | unsigned int limit = repl->entries_size; |
| 400 | unsigned int valid_hooks = repl->valid_hooks; |
| 401 | unsigned int offset = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 402 | int i; |
| 403 | |
Al Viro | e4fd77d | 2006-11-30 19:26:35 -0800 | [diff] [blame] | 404 | for (i = 0; i < NF_BR_NUMHOOKS; i++) |
| 405 | newinfo->hook_entry[i] = NULL; |
| 406 | |
| 407 | newinfo->entries_size = repl->entries_size; |
| 408 | newinfo->nentries = repl->nentries; |
| 409 | |
Al Viro | 70fe9af | 2006-11-30 19:26:14 -0800 | [diff] [blame] | 410 | while (offset < limit) { |
| 411 | size_t left = limit - offset; |
| 412 | struct ebt_entry *e = (void *)newinfo->entries + offset; |
Al Viro | bb2ef25 | 2006-11-30 19:22:42 -0800 | [diff] [blame] | 413 | |
Al Viro | 70fe9af | 2006-11-30 19:26:14 -0800 | [diff] [blame] | 414 | if (left < sizeof(unsigned int)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 415 | break; |
Al Viro | 22b440b | 2006-11-30 19:25:51 -0800 | [diff] [blame] | 416 | |
Al Viro | 70fe9af | 2006-11-30 19:26:14 -0800 | [diff] [blame] | 417 | for (i = 0; i < NF_BR_NUMHOOKS; i++) { |
| 418 | if ((valid_hooks & (1 << i)) == 0) |
| 419 | continue; |
| 420 | if ((char *)repl->hook_entry[i] == repl->entries + offset) |
| 421 | break; |
| 422 | } |
| 423 | |
| 424 | if (i != NF_BR_NUMHOOKS || !(e->bitmask & EBT_ENTRY_OR_ENTRIES)) { |
| 425 | if (e->bitmask != 0) { |
| 426 | /* we make userspace set this right, |
| 427 | so there is no misunderstanding */ |
| 428 | BUGPRINT("EBT_ENTRY_OR_ENTRIES shouldn't be set " |
| 429 | "in distinguisher\n"); |
| 430 | return -EINVAL; |
| 431 | } |
| 432 | if (i != NF_BR_NUMHOOKS) |
| 433 | newinfo->hook_entry[i] = (struct ebt_entries *)e; |
| 434 | if (left < sizeof(struct ebt_entries)) |
| 435 | break; |
| 436 | offset += sizeof(struct ebt_entries); |
| 437 | } else { |
| 438 | if (left < sizeof(struct ebt_entry)) |
| 439 | break; |
| 440 | if (left < e->next_offset) |
| 441 | break; |
| 442 | offset += e->next_offset; |
| 443 | } |
| 444 | } |
| 445 | if (offset != limit) { |
| 446 | BUGPRINT("entries_size too small\n"); |
| 447 | return -EINVAL; |
| 448 | } |
Al Viro | e4fd77d | 2006-11-30 19:26:35 -0800 | [diff] [blame] | 449 | |
| 450 | /* check if all valid hooks have a chain */ |
| 451 | for (i = 0; i < NF_BR_NUMHOOKS; i++) { |
| 452 | if (!newinfo->hook_entry[i] && |
| 453 | (valid_hooks & (1 << i))) { |
| 454 | BUGPRINT("Valid hook without chain\n"); |
| 455 | return -EINVAL; |
| 456 | } |
| 457 | } |
Al Viro | 70fe9af | 2006-11-30 19:26:14 -0800 | [diff] [blame] | 458 | return 0; |
Al Viro | 22b440b | 2006-11-30 19:25:51 -0800 | [diff] [blame] | 459 | } |
| 460 | |
| 461 | /* |
| 462 | * this one is very careful, as it is the first function |
| 463 | * to parse the userspace data |
| 464 | */ |
| 465 | static inline int |
| 466 | ebt_check_entry_size_and_hooks(struct ebt_entry *e, |
Al Viro | 0e79553 | 2006-11-30 19:27:13 -0800 | [diff] [blame] | 467 | struct ebt_table_info *newinfo, |
| 468 | unsigned int *n, unsigned int *cnt, |
| 469 | unsigned int *totalcnt, unsigned int *udc_cnt) |
Al Viro | 22b440b | 2006-11-30 19:25:51 -0800 | [diff] [blame] | 470 | { |
Al Viro | 22b440b | 2006-11-30 19:25:51 -0800 | [diff] [blame] | 471 | int i; |
| 472 | |
| 473 | for (i = 0; i < NF_BR_NUMHOOKS; i++) { |
Al Viro | 0e79553 | 2006-11-30 19:27:13 -0800 | [diff] [blame] | 474 | if ((void *)e == (void *)newinfo->hook_entry[i]) |
Al Viro | 22b440b | 2006-11-30 19:25:51 -0800 | [diff] [blame] | 475 | break; |
| 476 | } |
| 477 | /* beginning of a new chain |
| 478 | if i == NF_BR_NUMHOOKS it must be a user defined chain */ |
| 479 | if (i != NF_BR_NUMHOOKS || !e->bitmask) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 480 | /* this checks if the previous chain has as many entries |
| 481 | as it said it has */ |
| 482 | if (*n != *cnt) { |
| 483 | BUGPRINT("nentries does not equal the nr of entries " |
| 484 | "in the chain\n"); |
| 485 | return -EINVAL; |
| 486 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 487 | if (((struct ebt_entries *)e)->policy != EBT_DROP && |
| 488 | ((struct ebt_entries *)e)->policy != EBT_ACCEPT) { |
| 489 | /* only RETURN from udc */ |
| 490 | if (i != NF_BR_NUMHOOKS || |
| 491 | ((struct ebt_entries *)e)->policy != EBT_RETURN) { |
| 492 | BUGPRINT("bad policy\n"); |
| 493 | return -EINVAL; |
| 494 | } |
| 495 | } |
| 496 | if (i == NF_BR_NUMHOOKS) /* it's a user defined chain */ |
| 497 | (*udc_cnt)++; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 498 | if (((struct ebt_entries *)e)->counter_offset != *totalcnt) { |
| 499 | BUGPRINT("counter_offset != totalcnt"); |
| 500 | return -EINVAL; |
| 501 | } |
| 502 | *n = ((struct ebt_entries *)e)->nentries; |
| 503 | *cnt = 0; |
| 504 | return 0; |
| 505 | } |
| 506 | /* a plain old entry, heh */ |
| 507 | if (sizeof(struct ebt_entry) > e->watchers_offset || |
| 508 | e->watchers_offset > e->target_offset || |
| 509 | e->target_offset >= e->next_offset) { |
| 510 | BUGPRINT("entry offsets not in right order\n"); |
| 511 | return -EINVAL; |
| 512 | } |
| 513 | /* this is not checked anywhere else */ |
| 514 | if (e->next_offset - e->target_offset < sizeof(struct ebt_entry_target)) { |
| 515 | BUGPRINT("target size too small\n"); |
| 516 | return -EINVAL; |
| 517 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 518 | (*cnt)++; |
| 519 | (*totalcnt)++; |
| 520 | return 0; |
| 521 | } |
| 522 | |
| 523 | struct ebt_cl_stack |
| 524 | { |
| 525 | struct ebt_chainstack cs; |
| 526 | int from; |
| 527 | unsigned int hookmask; |
| 528 | }; |
| 529 | |
| 530 | /* |
| 531 | * we need these positions to check that the jumps to a different part of the |
| 532 | * entries is a jump to the beginning of a new chain. |
| 533 | */ |
| 534 | static inline int |
| 535 | ebt_get_udc_positions(struct ebt_entry *e, struct ebt_table_info *newinfo, |
Al Viro | 177abc3 | 2006-11-30 19:27:32 -0800 | [diff] [blame^] | 536 | unsigned int *n, struct ebt_cl_stack *udc) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 537 | { |
| 538 | int i; |
| 539 | |
| 540 | /* we're only interested in chain starts */ |
Al Viro | 40642f9 | 2006-11-30 19:24:12 -0800 | [diff] [blame] | 541 | if (e->bitmask) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 542 | return 0; |
| 543 | for (i = 0; i < NF_BR_NUMHOOKS; i++) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 544 | if (newinfo->hook_entry[i] == (struct ebt_entries *)e) |
| 545 | break; |
| 546 | } |
| 547 | /* only care about udc */ |
| 548 | if (i != NF_BR_NUMHOOKS) |
| 549 | return 0; |
| 550 | |
| 551 | udc[*n].cs.chaininfo = (struct ebt_entries *)e; |
| 552 | /* these initialisations are depended on later in check_chainloops() */ |
| 553 | udc[*n].cs.n = 0; |
| 554 | udc[*n].hookmask = 0; |
| 555 | |
| 556 | (*n)++; |
| 557 | return 0; |
| 558 | } |
| 559 | |
| 560 | static inline int |
| 561 | ebt_cleanup_match(struct ebt_entry_match *m, unsigned int *i) |
| 562 | { |
| 563 | if (i && (*i)-- == 0) |
| 564 | return 1; |
| 565 | if (m->u.match->destroy) |
| 566 | m->u.match->destroy(m->data, m->match_size); |
| 567 | module_put(m->u.match->me); |
| 568 | |
| 569 | return 0; |
| 570 | } |
| 571 | |
| 572 | static inline int |
| 573 | ebt_cleanup_watcher(struct ebt_entry_watcher *w, unsigned int *i) |
| 574 | { |
| 575 | if (i && (*i)-- == 0) |
| 576 | return 1; |
| 577 | if (w->u.watcher->destroy) |
| 578 | w->u.watcher->destroy(w->data, w->watcher_size); |
| 579 | module_put(w->u.watcher->me); |
| 580 | |
| 581 | return 0; |
| 582 | } |
| 583 | |
| 584 | static inline int |
| 585 | ebt_cleanup_entry(struct ebt_entry *e, unsigned int *cnt) |
| 586 | { |
| 587 | struct ebt_entry_target *t; |
| 588 | |
Al Viro | 40642f9 | 2006-11-30 19:24:12 -0800 | [diff] [blame] | 589 | if (e->bitmask == 0) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 590 | return 0; |
| 591 | /* we're done */ |
| 592 | if (cnt && (*cnt)-- == 0) |
| 593 | return 1; |
| 594 | EBT_WATCHER_ITERATE(e, ebt_cleanup_watcher, NULL); |
| 595 | EBT_MATCH_ITERATE(e, ebt_cleanup_match, NULL); |
| 596 | t = (struct ebt_entry_target *)(((char *)e) + e->target_offset); |
| 597 | if (t->u.target->destroy) |
| 598 | t->u.target->destroy(t->data, t->target_size); |
| 599 | module_put(t->u.target->me); |
| 600 | |
| 601 | return 0; |
| 602 | } |
| 603 | |
| 604 | static inline int |
| 605 | ebt_check_entry(struct ebt_entry *e, struct ebt_table_info *newinfo, |
| 606 | const char *name, unsigned int *cnt, unsigned int valid_hooks, |
| 607 | struct ebt_cl_stack *cl_s, unsigned int udc_cnt) |
| 608 | { |
| 609 | struct ebt_entry_target *t; |
| 610 | struct ebt_target *target; |
| 611 | unsigned int i, j, hook = 0, hookmask = 0; |
Al Viro | 14197d5 | 2006-11-30 19:25:21 -0800 | [diff] [blame] | 612 | size_t gap = e->next_offset - e->target_offset; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 613 | int ret; |
| 614 | |
| 615 | /* don't mess with the struct ebt_entries */ |
Al Viro | 40642f9 | 2006-11-30 19:24:12 -0800 | [diff] [blame] | 616 | if (e->bitmask == 0) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 617 | return 0; |
| 618 | |
| 619 | if (e->bitmask & ~EBT_F_MASK) { |
| 620 | BUGPRINT("Unknown flag for bitmask\n"); |
| 621 | return -EINVAL; |
| 622 | } |
| 623 | if (e->invflags & ~EBT_INV_MASK) { |
| 624 | BUGPRINT("Unknown flag for inv bitmask\n"); |
| 625 | return -EINVAL; |
| 626 | } |
| 627 | if ( (e->bitmask & EBT_NOPROTO) && (e->bitmask & EBT_802_3) ) { |
| 628 | BUGPRINT("NOPROTO & 802_3 not allowed\n"); |
| 629 | return -EINVAL; |
| 630 | } |
| 631 | /* what hook do we belong to? */ |
| 632 | for (i = 0; i < NF_BR_NUMHOOKS; i++) { |
| 633 | if ((valid_hooks & (1 << i)) == 0) |
| 634 | continue; |
| 635 | if ((char *)newinfo->hook_entry[i] < (char *)e) |
| 636 | hook = i; |
| 637 | else |
| 638 | break; |
| 639 | } |
| 640 | /* (1 << NF_BR_NUMHOOKS) tells the check functions the rule is on |
| 641 | a base chain */ |
| 642 | if (i < NF_BR_NUMHOOKS) |
| 643 | hookmask = (1 << hook) | (1 << NF_BR_NUMHOOKS); |
| 644 | else { |
| 645 | for (i = 0; i < udc_cnt; i++) |
| 646 | if ((char *)(cl_s[i].cs.chaininfo) > (char *)e) |
| 647 | break; |
| 648 | if (i == 0) |
| 649 | hookmask = (1 << hook) | (1 << NF_BR_NUMHOOKS); |
| 650 | else |
| 651 | hookmask = cl_s[i - 1].hookmask; |
| 652 | } |
| 653 | i = 0; |
| 654 | ret = EBT_MATCH_ITERATE(e, ebt_check_match, e, name, hookmask, &i); |
| 655 | if (ret != 0) |
| 656 | goto cleanup_matches; |
| 657 | j = 0; |
| 658 | ret = EBT_WATCHER_ITERATE(e, ebt_check_watcher, e, name, hookmask, &j); |
| 659 | if (ret != 0) |
| 660 | goto cleanup_watchers; |
| 661 | t = (struct ebt_entry_target *)(((char *)e) + e->target_offset); |
| 662 | target = find_target_lock(t->u.name, &ret, &ebt_mutex); |
| 663 | if (!target) |
| 664 | goto cleanup_watchers; |
| 665 | if (!try_module_get(target->me)) { |
Ingo Molnar | 57b47a5 | 2006-03-20 22:35:41 -0800 | [diff] [blame] | 666 | mutex_unlock(&ebt_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 667 | ret = -ENOENT; |
| 668 | goto cleanup_watchers; |
| 669 | } |
Ingo Molnar | 57b47a5 | 2006-03-20 22:35:41 -0800 | [diff] [blame] | 670 | mutex_unlock(&ebt_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 671 | |
| 672 | t->u.target = target; |
| 673 | if (t->u.target == &ebt_standard_target) { |
Al Viro | 14197d5 | 2006-11-30 19:25:21 -0800 | [diff] [blame] | 674 | if (gap < sizeof(struct ebt_standard_target)) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 675 | BUGPRINT("Standard target size too big\n"); |
| 676 | ret = -EFAULT; |
| 677 | goto cleanup_watchers; |
| 678 | } |
| 679 | if (((struct ebt_standard_target *)t)->verdict < |
| 680 | -NUM_STANDARD_TARGETS) { |
| 681 | BUGPRINT("Invalid standard target\n"); |
| 682 | ret = -EFAULT; |
| 683 | goto cleanup_watchers; |
| 684 | } |
Al Viro | 14197d5 | 2006-11-30 19:25:21 -0800 | [diff] [blame] | 685 | } else if (t->target_size > gap - sizeof(struct ebt_entry_target) || |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 686 | (t->u.target->check && |
| 687 | t->u.target->check(name, hookmask, e, t->data, t->target_size) != 0)){ |
| 688 | module_put(t->u.target->me); |
| 689 | ret = -EFAULT; |
| 690 | goto cleanup_watchers; |
| 691 | } |
| 692 | (*cnt)++; |
| 693 | return 0; |
| 694 | cleanup_watchers: |
| 695 | EBT_WATCHER_ITERATE(e, ebt_cleanup_watcher, &j); |
| 696 | cleanup_matches: |
| 697 | EBT_MATCH_ITERATE(e, ebt_cleanup_match, &i); |
| 698 | return ret; |
| 699 | } |
| 700 | |
| 701 | /* |
| 702 | * checks for loops and sets the hook mask for udc |
| 703 | * the hook mask for udc tells us from which base chains the udc can be |
| 704 | * accessed. This mask is a parameter to the check() functions of the extensions |
| 705 | */ |
| 706 | static int check_chainloops(struct ebt_entries *chain, struct ebt_cl_stack *cl_s, |
| 707 | unsigned int udc_cnt, unsigned int hooknr, char *base) |
| 708 | { |
| 709 | int i, chain_nr = -1, pos = 0, nentries = chain->nentries, verdict; |
| 710 | struct ebt_entry *e = (struct ebt_entry *)chain->data; |
| 711 | struct ebt_entry_target *t; |
| 712 | |
| 713 | while (pos < nentries || chain_nr != -1) { |
| 714 | /* end of udc, go back one 'recursion' step */ |
| 715 | if (pos == nentries) { |
| 716 | /* put back values of the time when this chain was called */ |
| 717 | e = cl_s[chain_nr].cs.e; |
| 718 | if (cl_s[chain_nr].from != -1) |
| 719 | nentries = |
| 720 | cl_s[cl_s[chain_nr].from].cs.chaininfo->nentries; |
| 721 | else |
| 722 | nentries = chain->nentries; |
| 723 | pos = cl_s[chain_nr].cs.n; |
| 724 | /* make sure we won't see a loop that isn't one */ |
| 725 | cl_s[chain_nr].cs.n = 0; |
| 726 | chain_nr = cl_s[chain_nr].from; |
| 727 | if (pos == nentries) |
| 728 | continue; |
| 729 | } |
| 730 | t = (struct ebt_entry_target *) |
| 731 | (((char *)e) + e->target_offset); |
| 732 | if (strcmp(t->u.name, EBT_STANDARD_TARGET)) |
| 733 | goto letscontinue; |
| 734 | if (e->target_offset + sizeof(struct ebt_standard_target) > |
| 735 | e->next_offset) { |
| 736 | BUGPRINT("Standard target size too big\n"); |
| 737 | return -1; |
| 738 | } |
| 739 | verdict = ((struct ebt_standard_target *)t)->verdict; |
| 740 | if (verdict >= 0) { /* jump to another chain */ |
| 741 | struct ebt_entries *hlp2 = |
| 742 | (struct ebt_entries *)(base + verdict); |
| 743 | for (i = 0; i < udc_cnt; i++) |
| 744 | if (hlp2 == cl_s[i].cs.chaininfo) |
| 745 | break; |
| 746 | /* bad destination or loop */ |
| 747 | if (i == udc_cnt) { |
| 748 | BUGPRINT("bad destination\n"); |
| 749 | return -1; |
| 750 | } |
| 751 | if (cl_s[i].cs.n) { |
| 752 | BUGPRINT("loop\n"); |
| 753 | return -1; |
| 754 | } |
Al Viro | 98a0824 | 2006-11-30 19:24:49 -0800 | [diff] [blame] | 755 | if (cl_s[i].hookmask & (1 << hooknr)) |
| 756 | goto letscontinue; |
| 757 | /* this can't be 0, so the loop test is correct */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 758 | cl_s[i].cs.n = pos + 1; |
| 759 | pos = 0; |
| 760 | cl_s[i].cs.e = ((void *)e + e->next_offset); |
| 761 | e = (struct ebt_entry *)(hlp2->data); |
| 762 | nentries = hlp2->nentries; |
| 763 | cl_s[i].from = chain_nr; |
| 764 | chain_nr = i; |
| 765 | /* this udc is accessible from the base chain for hooknr */ |
| 766 | cl_s[i].hookmask |= (1 << hooknr); |
| 767 | continue; |
| 768 | } |
| 769 | letscontinue: |
| 770 | e = (void *)e + e->next_offset; |
| 771 | pos++; |
| 772 | } |
| 773 | return 0; |
| 774 | } |
| 775 | |
| 776 | /* do the parsing of the table/chains/entries/matches/watchers/targets, heh */ |
| 777 | static int translate_table(struct ebt_replace *repl, |
| 778 | struct ebt_table_info *newinfo) |
| 779 | { |
| 780 | unsigned int i, j, k, udc_cnt; |
| 781 | int ret; |
| 782 | struct ebt_cl_stack *cl_s = NULL; /* used in the checking for chain loops */ |
| 783 | |
Al Viro | e4fd77d | 2006-11-30 19:26:35 -0800 | [diff] [blame] | 784 | ret = ebt_verify_pointers(repl, newinfo); |
| 785 | if (ret != 0) |
| 786 | return ret; |
| 787 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 788 | i = 0; |
Al Viro | 1f072c9 | 2006-11-30 19:26:53 -0800 | [diff] [blame] | 789 | while (i < NF_BR_NUMHOOKS && !newinfo->hook_entry[i]) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 790 | i++; |
| 791 | if (i == NF_BR_NUMHOOKS) { |
| 792 | BUGPRINT("No valid hooks specified\n"); |
| 793 | return -EINVAL; |
| 794 | } |
Al Viro | 1f072c9 | 2006-11-30 19:26:53 -0800 | [diff] [blame] | 795 | if (newinfo->hook_entry[i] != (struct ebt_entries *)newinfo->entries) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 796 | BUGPRINT("Chains don't start at beginning\n"); |
| 797 | return -EINVAL; |
| 798 | } |
| 799 | /* make sure chains are ordered after each other in same order |
| 800 | as their corresponding hooks */ |
| 801 | for (j = i + 1; j < NF_BR_NUMHOOKS; j++) { |
Al Viro | 1f072c9 | 2006-11-30 19:26:53 -0800 | [diff] [blame] | 802 | if (!newinfo->hook_entry[j]) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 803 | continue; |
Al Viro | 1f072c9 | 2006-11-30 19:26:53 -0800 | [diff] [blame] | 804 | if (newinfo->hook_entry[j] <= newinfo->hook_entry[i]) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 805 | BUGPRINT("Hook order must be followed\n"); |
| 806 | return -EINVAL; |
| 807 | } |
| 808 | i = j; |
| 809 | } |
| 810 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 811 | /* do some early checkings and initialize some things */ |
| 812 | i = 0; /* holds the expected nr. of entries for the chain */ |
| 813 | j = 0; /* holds the up to now counted entries for the chain */ |
| 814 | k = 0; /* holds the total nr. of entries, should equal |
| 815 | newinfo->nentries afterwards */ |
| 816 | udc_cnt = 0; /* will hold the nr. of user defined chains (udc) */ |
| 817 | ret = EBT_ENTRY_ITERATE(newinfo->entries, newinfo->entries_size, |
Al Viro | 0e79553 | 2006-11-30 19:27:13 -0800 | [diff] [blame] | 818 | ebt_check_entry_size_and_hooks, newinfo, |
| 819 | &i, &j, &k, &udc_cnt); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 820 | |
| 821 | if (ret != 0) |
| 822 | return ret; |
| 823 | |
| 824 | if (i != j) { |
| 825 | BUGPRINT("nentries does not equal the nr of entries in the " |
| 826 | "(last) chain\n"); |
| 827 | return -EINVAL; |
| 828 | } |
| 829 | if (k != newinfo->nentries) { |
| 830 | BUGPRINT("Total nentries is wrong\n"); |
| 831 | return -EINVAL; |
| 832 | } |
| 833 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 834 | /* get the location of the udc, put them in an array |
| 835 | while we're at it, allocate the chainstack */ |
| 836 | if (udc_cnt) { |
| 837 | /* this will get free'd in do_replace()/ebt_register_table() |
| 838 | if an error occurs */ |
Jayachandran C | 7ad4d2f | 2006-04-11 17:25:38 -0700 | [diff] [blame] | 839 | newinfo->chainstack = |
| 840 | vmalloc((highest_possible_processor_id()+1) |
| 841 | * sizeof(*(newinfo->chainstack))); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 842 | if (!newinfo->chainstack) |
| 843 | return -ENOMEM; |
KAMEZAWA Hiroyuki | 6f91204 | 2006-04-10 22:52:50 -0700 | [diff] [blame] | 844 | for_each_possible_cpu(i) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 845 | newinfo->chainstack[i] = |
Jayachandran C | 18bc89a | 2006-04-20 00:14:49 -0700 | [diff] [blame] | 846 | vmalloc(udc_cnt * sizeof(*(newinfo->chainstack[0]))); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 847 | if (!newinfo->chainstack[i]) { |
| 848 | while (i) |
| 849 | vfree(newinfo->chainstack[--i]); |
| 850 | vfree(newinfo->chainstack); |
| 851 | newinfo->chainstack = NULL; |
| 852 | return -ENOMEM; |
| 853 | } |
| 854 | } |
| 855 | |
Jayachandran C | 18bc89a | 2006-04-20 00:14:49 -0700 | [diff] [blame] | 856 | cl_s = vmalloc(udc_cnt * sizeof(*cl_s)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 857 | if (!cl_s) |
| 858 | return -ENOMEM; |
| 859 | i = 0; /* the i'th udc */ |
| 860 | EBT_ENTRY_ITERATE(newinfo->entries, newinfo->entries_size, |
Al Viro | 177abc3 | 2006-11-30 19:27:32 -0800 | [diff] [blame^] | 861 | ebt_get_udc_positions, newinfo, &i, cl_s); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 862 | /* sanity check */ |
| 863 | if (i != udc_cnt) { |
| 864 | BUGPRINT("i != udc_cnt\n"); |
| 865 | vfree(cl_s); |
| 866 | return -EFAULT; |
| 867 | } |
| 868 | } |
| 869 | |
| 870 | /* Check for loops */ |
| 871 | for (i = 0; i < NF_BR_NUMHOOKS; i++) |
Al Viro | 1f072c9 | 2006-11-30 19:26:53 -0800 | [diff] [blame] | 872 | if (newinfo->hook_entry[i]) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 873 | if (check_chainloops(newinfo->hook_entry[i], |
| 874 | cl_s, udc_cnt, i, newinfo->entries)) { |
James Lamanna | 68d3187 | 2005-06-22 22:12:57 -0700 | [diff] [blame] | 875 | vfree(cl_s); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 876 | return -EINVAL; |
| 877 | } |
| 878 | |
| 879 | /* we now know the following (along with E=mc²): |
| 880 | - the nr of entries in each chain is right |
| 881 | - the size of the allocated space is right |
| 882 | - all valid hooks have a corresponding chain |
| 883 | - there are no loops |
| 884 | - wrong data can still be on the level of a single entry |
| 885 | - could be there are jumps to places that are not the |
| 886 | beginning of a chain. This can only occur in chains that |
| 887 | are not accessible from any base chains, so we don't care. */ |
| 888 | |
| 889 | /* used to know what we need to clean up if something goes wrong */ |
| 890 | i = 0; |
| 891 | ret = EBT_ENTRY_ITERATE(newinfo->entries, newinfo->entries_size, |
| 892 | ebt_check_entry, newinfo, repl->name, &i, repl->valid_hooks, |
| 893 | cl_s, udc_cnt); |
| 894 | if (ret != 0) { |
| 895 | EBT_ENTRY_ITERATE(newinfo->entries, newinfo->entries_size, |
| 896 | ebt_cleanup_entry, &i); |
| 897 | } |
James Lamanna | 68d3187 | 2005-06-22 22:12:57 -0700 | [diff] [blame] | 898 | vfree(cl_s); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 899 | return ret; |
| 900 | } |
| 901 | |
| 902 | /* called under write_lock */ |
| 903 | static void get_counters(struct ebt_counter *oldcounters, |
| 904 | struct ebt_counter *counters, unsigned int nentries) |
| 905 | { |
| 906 | int i, cpu; |
| 907 | struct ebt_counter *counter_base; |
| 908 | |
| 909 | /* counters of cpu 0 */ |
| 910 | memcpy(counters, oldcounters, |
David S. Miller | c8923c6 | 2005-10-13 14:41:23 -0700 | [diff] [blame] | 911 | sizeof(struct ebt_counter) * nentries); |
| 912 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 913 | /* add other counters to those of cpu 0 */ |
KAMEZAWA Hiroyuki | 6f91204 | 2006-04-10 22:52:50 -0700 | [diff] [blame] | 914 | for_each_possible_cpu(cpu) { |
David S. Miller | c8923c6 | 2005-10-13 14:41:23 -0700 | [diff] [blame] | 915 | if (cpu == 0) |
| 916 | continue; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 917 | counter_base = COUNTER_BASE(oldcounters, nentries, cpu); |
| 918 | for (i = 0; i < nentries; i++) { |
| 919 | counters[i].pcnt += counter_base[i].pcnt; |
| 920 | counters[i].bcnt += counter_base[i].bcnt; |
| 921 | } |
| 922 | } |
| 923 | } |
| 924 | |
| 925 | /* replace the table */ |
| 926 | static int do_replace(void __user *user, unsigned int len) |
| 927 | { |
| 928 | int ret, i, countersize; |
| 929 | struct ebt_table_info *newinfo; |
| 930 | struct ebt_replace tmp; |
| 931 | struct ebt_table *t; |
| 932 | struct ebt_counter *counterstmp = NULL; |
| 933 | /* used to be able to unlock earlier */ |
| 934 | struct ebt_table_info *table; |
| 935 | |
| 936 | if (copy_from_user(&tmp, user, sizeof(tmp)) != 0) |
| 937 | return -EFAULT; |
| 938 | |
| 939 | if (len != sizeof(tmp) + tmp.entries_size) { |
| 940 | BUGPRINT("Wrong len argument\n"); |
| 941 | return -EINVAL; |
| 942 | } |
| 943 | |
| 944 | if (tmp.entries_size == 0) { |
| 945 | BUGPRINT("Entries_size never zero\n"); |
| 946 | return -EINVAL; |
| 947 | } |
Kirill Korotaev | ee4bb81 | 2006-02-04 02:16:56 -0800 | [diff] [blame] | 948 | /* overflow check */ |
| 949 | if (tmp.nentries >= ((INT_MAX - sizeof(struct ebt_table_info)) / NR_CPUS - |
| 950 | SMP_CACHE_BYTES) / sizeof(struct ebt_counter)) |
| 951 | return -ENOMEM; |
| 952 | if (tmp.num_counters >= INT_MAX / sizeof(struct ebt_counter)) |
| 953 | return -ENOMEM; |
| 954 | |
David S. Miller | c8923c6 | 2005-10-13 14:41:23 -0700 | [diff] [blame] | 955 | countersize = COUNTER_OFFSET(tmp.nentries) * |
| 956 | (highest_possible_processor_id()+1); |
Jayachandran C | 18bc89a | 2006-04-20 00:14:49 -0700 | [diff] [blame] | 957 | newinfo = vmalloc(sizeof(*newinfo) + countersize); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 958 | if (!newinfo) |
| 959 | return -ENOMEM; |
| 960 | |
| 961 | if (countersize) |
| 962 | memset(newinfo->counters, 0, countersize); |
| 963 | |
Kris Katterjohn | 8b3a700 | 2006-01-11 15:56:43 -0800 | [diff] [blame] | 964 | newinfo->entries = vmalloc(tmp.entries_size); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 965 | if (!newinfo->entries) { |
| 966 | ret = -ENOMEM; |
| 967 | goto free_newinfo; |
| 968 | } |
| 969 | if (copy_from_user( |
| 970 | newinfo->entries, tmp.entries, tmp.entries_size) != 0) { |
| 971 | BUGPRINT("Couldn't copy entries from userspace\n"); |
| 972 | ret = -EFAULT; |
| 973 | goto free_entries; |
| 974 | } |
| 975 | |
| 976 | /* the user wants counters back |
| 977 | the check on the size is done later, when we have the lock */ |
| 978 | if (tmp.num_counters) { |
Jayachandran C | 18bc89a | 2006-04-20 00:14:49 -0700 | [diff] [blame] | 979 | counterstmp = vmalloc(tmp.num_counters * sizeof(*counterstmp)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 980 | if (!counterstmp) { |
| 981 | ret = -ENOMEM; |
| 982 | goto free_entries; |
| 983 | } |
| 984 | } |
| 985 | else |
| 986 | counterstmp = NULL; |
| 987 | |
| 988 | /* this can get initialized by translate_table() */ |
| 989 | newinfo->chainstack = NULL; |
| 990 | ret = translate_table(&tmp, newinfo); |
| 991 | |
| 992 | if (ret != 0) |
| 993 | goto free_counterstmp; |
| 994 | |
| 995 | t = find_table_lock(tmp.name, &ret, &ebt_mutex); |
| 996 | if (!t) { |
| 997 | ret = -ENOENT; |
| 998 | goto free_iterate; |
| 999 | } |
| 1000 | |
| 1001 | /* the table doesn't like it */ |
| 1002 | if (t->check && (ret = t->check(newinfo, tmp.valid_hooks))) |
| 1003 | goto free_unlock; |
| 1004 | |
| 1005 | if (tmp.num_counters && tmp.num_counters != t->private->nentries) { |
| 1006 | BUGPRINT("Wrong nr. of counters requested\n"); |
| 1007 | ret = -EINVAL; |
| 1008 | goto free_unlock; |
| 1009 | } |
| 1010 | |
| 1011 | /* we have the mutex lock, so no danger in reading this pointer */ |
| 1012 | table = t->private; |
| 1013 | /* make sure the table can only be rmmod'ed if it contains no rules */ |
| 1014 | if (!table->nentries && newinfo->nentries && !try_module_get(t->me)) { |
| 1015 | ret = -ENOENT; |
| 1016 | goto free_unlock; |
| 1017 | } else if (table->nentries && !newinfo->nentries) |
| 1018 | module_put(t->me); |
| 1019 | /* we need an atomic snapshot of the counters */ |
| 1020 | write_lock_bh(&t->lock); |
| 1021 | if (tmp.num_counters) |
| 1022 | get_counters(t->private->counters, counterstmp, |
| 1023 | t->private->nentries); |
| 1024 | |
| 1025 | t->private = newinfo; |
| 1026 | write_unlock_bh(&t->lock); |
Ingo Molnar | 57b47a5 | 2006-03-20 22:35:41 -0800 | [diff] [blame] | 1027 | mutex_unlock(&ebt_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1028 | /* so, a user can change the chains while having messed up her counter |
| 1029 | allocation. Only reason why this is done is because this way the lock |
| 1030 | is held only once, while this doesn't bring the kernel into a |
| 1031 | dangerous state. */ |
| 1032 | if (tmp.num_counters && |
| 1033 | copy_to_user(tmp.counters, counterstmp, |
| 1034 | tmp.num_counters * sizeof(struct ebt_counter))) { |
| 1035 | BUGPRINT("Couldn't copy counters to userspace\n"); |
| 1036 | ret = -EFAULT; |
| 1037 | } |
| 1038 | else |
| 1039 | ret = 0; |
| 1040 | |
| 1041 | /* decrease module count and free resources */ |
| 1042 | EBT_ENTRY_ITERATE(table->entries, table->entries_size, |
| 1043 | ebt_cleanup_entry, NULL); |
| 1044 | |
| 1045 | vfree(table->entries); |
| 1046 | if (table->chainstack) { |
KAMEZAWA Hiroyuki | 6f91204 | 2006-04-10 22:52:50 -0700 | [diff] [blame] | 1047 | for_each_possible_cpu(i) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1048 | vfree(table->chainstack[i]); |
| 1049 | vfree(table->chainstack); |
| 1050 | } |
| 1051 | vfree(table); |
| 1052 | |
James Lamanna | 68d3187 | 2005-06-22 22:12:57 -0700 | [diff] [blame] | 1053 | vfree(counterstmp); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1054 | return ret; |
| 1055 | |
| 1056 | free_unlock: |
Ingo Molnar | 57b47a5 | 2006-03-20 22:35:41 -0800 | [diff] [blame] | 1057 | mutex_unlock(&ebt_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1058 | free_iterate: |
| 1059 | EBT_ENTRY_ITERATE(newinfo->entries, newinfo->entries_size, |
| 1060 | ebt_cleanup_entry, NULL); |
| 1061 | free_counterstmp: |
James Lamanna | 68d3187 | 2005-06-22 22:12:57 -0700 | [diff] [blame] | 1062 | vfree(counterstmp); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1063 | /* can be initialized in translate_table() */ |
| 1064 | if (newinfo->chainstack) { |
KAMEZAWA Hiroyuki | 6f91204 | 2006-04-10 22:52:50 -0700 | [diff] [blame] | 1065 | for_each_possible_cpu(i) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1066 | vfree(newinfo->chainstack[i]); |
| 1067 | vfree(newinfo->chainstack); |
| 1068 | } |
| 1069 | free_entries: |
James Lamanna | 68d3187 | 2005-06-22 22:12:57 -0700 | [diff] [blame] | 1070 | vfree(newinfo->entries); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1071 | free_newinfo: |
James Lamanna | 68d3187 | 2005-06-22 22:12:57 -0700 | [diff] [blame] | 1072 | vfree(newinfo); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1073 | return ret; |
| 1074 | } |
| 1075 | |
| 1076 | int ebt_register_target(struct ebt_target *target) |
| 1077 | { |
Patrick McHardy | df0933d | 2006-09-20 11:57:53 -0700 | [diff] [blame] | 1078 | struct ebt_target *t; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1079 | int ret; |
| 1080 | |
Ingo Molnar | 57b47a5 | 2006-03-20 22:35:41 -0800 | [diff] [blame] | 1081 | ret = mutex_lock_interruptible(&ebt_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1082 | if (ret != 0) |
| 1083 | return ret; |
Patrick McHardy | df0933d | 2006-09-20 11:57:53 -0700 | [diff] [blame] | 1084 | list_for_each_entry(t, &ebt_targets, list) { |
| 1085 | if (strcmp(t->name, target->name) == 0) { |
| 1086 | mutex_unlock(&ebt_mutex); |
| 1087 | return -EEXIST; |
| 1088 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1089 | } |
Patrick McHardy | df0933d | 2006-09-20 11:57:53 -0700 | [diff] [blame] | 1090 | list_add(&target->list, &ebt_targets); |
Ingo Molnar | 57b47a5 | 2006-03-20 22:35:41 -0800 | [diff] [blame] | 1091 | mutex_unlock(&ebt_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1092 | |
| 1093 | return 0; |
| 1094 | } |
| 1095 | |
| 1096 | void ebt_unregister_target(struct ebt_target *target) |
| 1097 | { |
Ingo Molnar | 57b47a5 | 2006-03-20 22:35:41 -0800 | [diff] [blame] | 1098 | mutex_lock(&ebt_mutex); |
Patrick McHardy | df0933d | 2006-09-20 11:57:53 -0700 | [diff] [blame] | 1099 | list_del(&target->list); |
Ingo Molnar | 57b47a5 | 2006-03-20 22:35:41 -0800 | [diff] [blame] | 1100 | mutex_unlock(&ebt_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1101 | } |
| 1102 | |
| 1103 | int ebt_register_match(struct ebt_match *match) |
| 1104 | { |
Patrick McHardy | df0933d | 2006-09-20 11:57:53 -0700 | [diff] [blame] | 1105 | struct ebt_match *m; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1106 | int ret; |
| 1107 | |
Ingo Molnar | 57b47a5 | 2006-03-20 22:35:41 -0800 | [diff] [blame] | 1108 | ret = mutex_lock_interruptible(&ebt_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1109 | if (ret != 0) |
| 1110 | return ret; |
Patrick McHardy | df0933d | 2006-09-20 11:57:53 -0700 | [diff] [blame] | 1111 | list_for_each_entry(m, &ebt_matches, list) { |
| 1112 | if (strcmp(m->name, match->name) == 0) { |
| 1113 | mutex_unlock(&ebt_mutex); |
| 1114 | return -EEXIST; |
| 1115 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1116 | } |
Patrick McHardy | df0933d | 2006-09-20 11:57:53 -0700 | [diff] [blame] | 1117 | list_add(&match->list, &ebt_matches); |
Ingo Molnar | 57b47a5 | 2006-03-20 22:35:41 -0800 | [diff] [blame] | 1118 | mutex_unlock(&ebt_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1119 | |
| 1120 | return 0; |
| 1121 | } |
| 1122 | |
| 1123 | void ebt_unregister_match(struct ebt_match *match) |
| 1124 | { |
Ingo Molnar | 57b47a5 | 2006-03-20 22:35:41 -0800 | [diff] [blame] | 1125 | mutex_lock(&ebt_mutex); |
Patrick McHardy | df0933d | 2006-09-20 11:57:53 -0700 | [diff] [blame] | 1126 | list_del(&match->list); |
Ingo Molnar | 57b47a5 | 2006-03-20 22:35:41 -0800 | [diff] [blame] | 1127 | mutex_unlock(&ebt_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1128 | } |
| 1129 | |
| 1130 | int ebt_register_watcher(struct ebt_watcher *watcher) |
| 1131 | { |
Patrick McHardy | df0933d | 2006-09-20 11:57:53 -0700 | [diff] [blame] | 1132 | struct ebt_watcher *w; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1133 | int ret; |
| 1134 | |
Ingo Molnar | 57b47a5 | 2006-03-20 22:35:41 -0800 | [diff] [blame] | 1135 | ret = mutex_lock_interruptible(&ebt_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1136 | if (ret != 0) |
| 1137 | return ret; |
Patrick McHardy | df0933d | 2006-09-20 11:57:53 -0700 | [diff] [blame] | 1138 | list_for_each_entry(w, &ebt_watchers, list) { |
| 1139 | if (strcmp(w->name, watcher->name) == 0) { |
| 1140 | mutex_unlock(&ebt_mutex); |
| 1141 | return -EEXIST; |
| 1142 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1143 | } |
Patrick McHardy | df0933d | 2006-09-20 11:57:53 -0700 | [diff] [blame] | 1144 | list_add(&watcher->list, &ebt_watchers); |
Ingo Molnar | 57b47a5 | 2006-03-20 22:35:41 -0800 | [diff] [blame] | 1145 | mutex_unlock(&ebt_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1146 | |
| 1147 | return 0; |
| 1148 | } |
| 1149 | |
| 1150 | void ebt_unregister_watcher(struct ebt_watcher *watcher) |
| 1151 | { |
Ingo Molnar | 57b47a5 | 2006-03-20 22:35:41 -0800 | [diff] [blame] | 1152 | mutex_lock(&ebt_mutex); |
Patrick McHardy | df0933d | 2006-09-20 11:57:53 -0700 | [diff] [blame] | 1153 | list_del(&watcher->list); |
Ingo Molnar | 57b47a5 | 2006-03-20 22:35:41 -0800 | [diff] [blame] | 1154 | mutex_unlock(&ebt_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1155 | } |
| 1156 | |
| 1157 | int ebt_register_table(struct ebt_table *table) |
| 1158 | { |
| 1159 | struct ebt_table_info *newinfo; |
Patrick McHardy | df0933d | 2006-09-20 11:57:53 -0700 | [diff] [blame] | 1160 | struct ebt_table *t; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1161 | int ret, i, countersize; |
| 1162 | |
| 1163 | if (!table || !table->table ||!table->table->entries || |
| 1164 | table->table->entries_size == 0 || |
| 1165 | table->table->counters || table->private) { |
| 1166 | BUGPRINT("Bad table data for ebt_register_table!!!\n"); |
| 1167 | return -EINVAL; |
| 1168 | } |
| 1169 | |
David S. Miller | c8923c6 | 2005-10-13 14:41:23 -0700 | [diff] [blame] | 1170 | countersize = COUNTER_OFFSET(table->table->nentries) * |
| 1171 | (highest_possible_processor_id()+1); |
Jayachandran C | 18bc89a | 2006-04-20 00:14:49 -0700 | [diff] [blame] | 1172 | newinfo = vmalloc(sizeof(*newinfo) + countersize); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1173 | ret = -ENOMEM; |
| 1174 | if (!newinfo) |
| 1175 | return -ENOMEM; |
| 1176 | |
Kris Katterjohn | 8b3a700 | 2006-01-11 15:56:43 -0800 | [diff] [blame] | 1177 | newinfo->entries = vmalloc(table->table->entries_size); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1178 | if (!(newinfo->entries)) |
| 1179 | goto free_newinfo; |
| 1180 | |
| 1181 | memcpy(newinfo->entries, table->table->entries, |
| 1182 | table->table->entries_size); |
| 1183 | |
| 1184 | if (countersize) |
| 1185 | memset(newinfo->counters, 0, countersize); |
| 1186 | |
| 1187 | /* fill in newinfo and parse the entries */ |
| 1188 | newinfo->chainstack = NULL; |
| 1189 | ret = translate_table(table->table, newinfo); |
| 1190 | if (ret != 0) { |
| 1191 | BUGPRINT("Translate_table failed\n"); |
| 1192 | goto free_chainstack; |
| 1193 | } |
| 1194 | |
| 1195 | if (table->check && table->check(newinfo, table->valid_hooks)) { |
| 1196 | BUGPRINT("The table doesn't like its own initial data, lol\n"); |
| 1197 | return -EINVAL; |
| 1198 | } |
| 1199 | |
| 1200 | table->private = newinfo; |
| 1201 | rwlock_init(&table->lock); |
Ingo Molnar | 57b47a5 | 2006-03-20 22:35:41 -0800 | [diff] [blame] | 1202 | ret = mutex_lock_interruptible(&ebt_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1203 | if (ret != 0) |
| 1204 | goto free_chainstack; |
| 1205 | |
Patrick McHardy | df0933d | 2006-09-20 11:57:53 -0700 | [diff] [blame] | 1206 | list_for_each_entry(t, &ebt_tables, list) { |
| 1207 | if (strcmp(t->name, table->name) == 0) { |
| 1208 | ret = -EEXIST; |
| 1209 | BUGPRINT("Table name already exists\n"); |
| 1210 | goto free_unlock; |
| 1211 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1212 | } |
| 1213 | |
| 1214 | /* Hold a reference count if the chains aren't empty */ |
| 1215 | if (newinfo->nentries && !try_module_get(table->me)) { |
| 1216 | ret = -ENOENT; |
| 1217 | goto free_unlock; |
| 1218 | } |
Patrick McHardy | df0933d | 2006-09-20 11:57:53 -0700 | [diff] [blame] | 1219 | list_add(&table->list, &ebt_tables); |
Ingo Molnar | 57b47a5 | 2006-03-20 22:35:41 -0800 | [diff] [blame] | 1220 | mutex_unlock(&ebt_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1221 | return 0; |
| 1222 | free_unlock: |
Ingo Molnar | 57b47a5 | 2006-03-20 22:35:41 -0800 | [diff] [blame] | 1223 | mutex_unlock(&ebt_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1224 | free_chainstack: |
| 1225 | if (newinfo->chainstack) { |
KAMEZAWA Hiroyuki | 6f91204 | 2006-04-10 22:52:50 -0700 | [diff] [blame] | 1226 | for_each_possible_cpu(i) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1227 | vfree(newinfo->chainstack[i]); |
| 1228 | vfree(newinfo->chainstack); |
| 1229 | } |
| 1230 | vfree(newinfo->entries); |
| 1231 | free_newinfo: |
| 1232 | vfree(newinfo); |
| 1233 | return ret; |
| 1234 | } |
| 1235 | |
| 1236 | void ebt_unregister_table(struct ebt_table *table) |
| 1237 | { |
| 1238 | int i; |
| 1239 | |
| 1240 | if (!table) { |
| 1241 | BUGPRINT("Request to unregister NULL table!!!\n"); |
| 1242 | return; |
| 1243 | } |
Ingo Molnar | 57b47a5 | 2006-03-20 22:35:41 -0800 | [diff] [blame] | 1244 | mutex_lock(&ebt_mutex); |
Patrick McHardy | df0933d | 2006-09-20 11:57:53 -0700 | [diff] [blame] | 1245 | list_del(&table->list); |
Ingo Molnar | 57b47a5 | 2006-03-20 22:35:41 -0800 | [diff] [blame] | 1246 | mutex_unlock(&ebt_mutex); |
James Lamanna | 68d3187 | 2005-06-22 22:12:57 -0700 | [diff] [blame] | 1247 | vfree(table->private->entries); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1248 | if (table->private->chainstack) { |
KAMEZAWA Hiroyuki | 6f91204 | 2006-04-10 22:52:50 -0700 | [diff] [blame] | 1249 | for_each_possible_cpu(i) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1250 | vfree(table->private->chainstack[i]); |
| 1251 | vfree(table->private->chainstack); |
| 1252 | } |
| 1253 | vfree(table->private); |
| 1254 | } |
| 1255 | |
| 1256 | /* userspace just supplied us with counters */ |
| 1257 | static int update_counters(void __user *user, unsigned int len) |
| 1258 | { |
| 1259 | int i, ret; |
| 1260 | struct ebt_counter *tmp; |
| 1261 | struct ebt_replace hlp; |
| 1262 | struct ebt_table *t; |
| 1263 | |
| 1264 | if (copy_from_user(&hlp, user, sizeof(hlp))) |
| 1265 | return -EFAULT; |
| 1266 | |
| 1267 | if (len != sizeof(hlp) + hlp.num_counters * sizeof(struct ebt_counter)) |
| 1268 | return -EINVAL; |
| 1269 | if (hlp.num_counters == 0) |
| 1270 | return -EINVAL; |
| 1271 | |
Jayachandran C | 18bc89a | 2006-04-20 00:14:49 -0700 | [diff] [blame] | 1272 | if (!(tmp = vmalloc(hlp.num_counters * sizeof(*tmp)))) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1273 | MEMPRINT("Update_counters && nomemory\n"); |
| 1274 | return -ENOMEM; |
| 1275 | } |
| 1276 | |
| 1277 | t = find_table_lock(hlp.name, &ret, &ebt_mutex); |
| 1278 | if (!t) |
| 1279 | goto free_tmp; |
| 1280 | |
| 1281 | if (hlp.num_counters != t->private->nentries) { |
| 1282 | BUGPRINT("Wrong nr of counters\n"); |
| 1283 | ret = -EINVAL; |
| 1284 | goto unlock_mutex; |
| 1285 | } |
| 1286 | |
| 1287 | if ( copy_from_user(tmp, hlp.counters, |
| 1288 | hlp.num_counters * sizeof(struct ebt_counter)) ) { |
| 1289 | BUGPRINT("Updata_counters && !cfu\n"); |
| 1290 | ret = -EFAULT; |
| 1291 | goto unlock_mutex; |
| 1292 | } |
| 1293 | |
| 1294 | /* we want an atomic add of the counters */ |
| 1295 | write_lock_bh(&t->lock); |
| 1296 | |
| 1297 | /* we add to the counters of the first cpu */ |
| 1298 | for (i = 0; i < hlp.num_counters; i++) { |
| 1299 | t->private->counters[i].pcnt += tmp[i].pcnt; |
| 1300 | t->private->counters[i].bcnt += tmp[i].bcnt; |
| 1301 | } |
| 1302 | |
| 1303 | write_unlock_bh(&t->lock); |
| 1304 | ret = 0; |
| 1305 | unlock_mutex: |
Ingo Molnar | 57b47a5 | 2006-03-20 22:35:41 -0800 | [diff] [blame] | 1306 | mutex_unlock(&ebt_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1307 | free_tmp: |
| 1308 | vfree(tmp); |
| 1309 | return ret; |
| 1310 | } |
| 1311 | |
| 1312 | static inline int ebt_make_matchname(struct ebt_entry_match *m, |
| 1313 | char *base, char *ubase) |
| 1314 | { |
| 1315 | char *hlp = ubase - base + (char *)m; |
| 1316 | if (copy_to_user(hlp, m->u.match->name, EBT_FUNCTION_MAXNAMELEN)) |
| 1317 | return -EFAULT; |
| 1318 | return 0; |
| 1319 | } |
| 1320 | |
| 1321 | static inline int ebt_make_watchername(struct ebt_entry_watcher *w, |
| 1322 | char *base, char *ubase) |
| 1323 | { |
| 1324 | char *hlp = ubase - base + (char *)w; |
| 1325 | if (copy_to_user(hlp , w->u.watcher->name, EBT_FUNCTION_MAXNAMELEN)) |
| 1326 | return -EFAULT; |
| 1327 | return 0; |
| 1328 | } |
| 1329 | |
| 1330 | static inline int ebt_make_names(struct ebt_entry *e, char *base, char *ubase) |
| 1331 | { |
| 1332 | int ret; |
| 1333 | char *hlp; |
| 1334 | struct ebt_entry_target *t; |
| 1335 | |
Al Viro | 40642f9 | 2006-11-30 19:24:12 -0800 | [diff] [blame] | 1336 | if (e->bitmask == 0) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1337 | return 0; |
| 1338 | |
| 1339 | hlp = ubase - base + (char *)e + e->target_offset; |
| 1340 | t = (struct ebt_entry_target *)(((char *)e) + e->target_offset); |
| 1341 | |
| 1342 | ret = EBT_MATCH_ITERATE(e, ebt_make_matchname, base, ubase); |
| 1343 | if (ret != 0) |
| 1344 | return ret; |
| 1345 | ret = EBT_WATCHER_ITERATE(e, ebt_make_watchername, base, ubase); |
| 1346 | if (ret != 0) |
| 1347 | return ret; |
| 1348 | if (copy_to_user(hlp, t->u.target->name, EBT_FUNCTION_MAXNAMELEN)) |
| 1349 | return -EFAULT; |
| 1350 | return 0; |
| 1351 | } |
| 1352 | |
Ingo Molnar | 57b47a5 | 2006-03-20 22:35:41 -0800 | [diff] [blame] | 1353 | /* called with ebt_mutex locked */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1354 | static int copy_everything_to_user(struct ebt_table *t, void __user *user, |
| 1355 | int *len, int cmd) |
| 1356 | { |
| 1357 | struct ebt_replace tmp; |
| 1358 | struct ebt_counter *counterstmp, *oldcounters; |
| 1359 | unsigned int entries_size, nentries; |
| 1360 | char *entries; |
| 1361 | |
| 1362 | if (cmd == EBT_SO_GET_ENTRIES) { |
| 1363 | entries_size = t->private->entries_size; |
| 1364 | nentries = t->private->nentries; |
| 1365 | entries = t->private->entries; |
| 1366 | oldcounters = t->private->counters; |
| 1367 | } else { |
| 1368 | entries_size = t->table->entries_size; |
| 1369 | nentries = t->table->nentries; |
| 1370 | entries = t->table->entries; |
| 1371 | oldcounters = t->table->counters; |
| 1372 | } |
| 1373 | |
| 1374 | if (copy_from_user(&tmp, user, sizeof(tmp))) { |
| 1375 | BUGPRINT("Cfu didn't work\n"); |
| 1376 | return -EFAULT; |
| 1377 | } |
| 1378 | |
| 1379 | if (*len != sizeof(struct ebt_replace) + entries_size + |
| 1380 | (tmp.num_counters? nentries * sizeof(struct ebt_counter): 0)) { |
| 1381 | BUGPRINT("Wrong size\n"); |
| 1382 | return -EINVAL; |
| 1383 | } |
| 1384 | |
| 1385 | if (tmp.nentries != nentries) { |
| 1386 | BUGPRINT("Nentries wrong\n"); |
| 1387 | return -EINVAL; |
| 1388 | } |
| 1389 | |
| 1390 | if (tmp.entries_size != entries_size) { |
| 1391 | BUGPRINT("Wrong size\n"); |
| 1392 | return -EINVAL; |
| 1393 | } |
| 1394 | |
| 1395 | /* userspace might not need the counters */ |
| 1396 | if (tmp.num_counters) { |
| 1397 | if (tmp.num_counters != nentries) { |
| 1398 | BUGPRINT("Num_counters wrong\n"); |
| 1399 | return -EINVAL; |
| 1400 | } |
Jayachandran C | 18bc89a | 2006-04-20 00:14:49 -0700 | [diff] [blame] | 1401 | counterstmp = vmalloc(nentries * sizeof(*counterstmp)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1402 | if (!counterstmp) { |
| 1403 | MEMPRINT("Couldn't copy counters, out of memory\n"); |
| 1404 | return -ENOMEM; |
| 1405 | } |
| 1406 | write_lock_bh(&t->lock); |
| 1407 | get_counters(oldcounters, counterstmp, nentries); |
| 1408 | write_unlock_bh(&t->lock); |
| 1409 | |
| 1410 | if (copy_to_user(tmp.counters, counterstmp, |
| 1411 | nentries * sizeof(struct ebt_counter))) { |
| 1412 | BUGPRINT("Couldn't copy counters to userspace\n"); |
| 1413 | vfree(counterstmp); |
| 1414 | return -EFAULT; |
| 1415 | } |
| 1416 | vfree(counterstmp); |
| 1417 | } |
| 1418 | |
| 1419 | if (copy_to_user(tmp.entries, entries, entries_size)) { |
| 1420 | BUGPRINT("Couldn't copy entries to userspace\n"); |
| 1421 | return -EFAULT; |
| 1422 | } |
| 1423 | /* set the match/watcher/target names right */ |
| 1424 | return EBT_ENTRY_ITERATE(entries, entries_size, |
| 1425 | ebt_make_names, entries, tmp.entries); |
| 1426 | } |
| 1427 | |
| 1428 | static int do_ebt_set_ctl(struct sock *sk, |
| 1429 | int cmd, void __user *user, unsigned int len) |
| 1430 | { |
| 1431 | int ret; |
| 1432 | |
| 1433 | switch(cmd) { |
| 1434 | case EBT_SO_SET_ENTRIES: |
| 1435 | ret = do_replace(user, len); |
| 1436 | break; |
| 1437 | case EBT_SO_SET_COUNTERS: |
| 1438 | ret = update_counters(user, len); |
| 1439 | break; |
| 1440 | default: |
| 1441 | ret = -EINVAL; |
| 1442 | } |
| 1443 | return ret; |
| 1444 | } |
| 1445 | |
| 1446 | static int do_ebt_get_ctl(struct sock *sk, int cmd, void __user *user, int *len) |
| 1447 | { |
| 1448 | int ret; |
| 1449 | struct ebt_replace tmp; |
| 1450 | struct ebt_table *t; |
| 1451 | |
| 1452 | if (copy_from_user(&tmp, user, sizeof(tmp))) |
| 1453 | return -EFAULT; |
| 1454 | |
| 1455 | t = find_table_lock(tmp.name, &ret, &ebt_mutex); |
| 1456 | if (!t) |
| 1457 | return ret; |
| 1458 | |
| 1459 | switch(cmd) { |
| 1460 | case EBT_SO_GET_INFO: |
| 1461 | case EBT_SO_GET_INIT_INFO: |
| 1462 | if (*len != sizeof(struct ebt_replace)){ |
| 1463 | ret = -EINVAL; |
Ingo Molnar | 57b47a5 | 2006-03-20 22:35:41 -0800 | [diff] [blame] | 1464 | mutex_unlock(&ebt_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1465 | break; |
| 1466 | } |
| 1467 | if (cmd == EBT_SO_GET_INFO) { |
| 1468 | tmp.nentries = t->private->nentries; |
| 1469 | tmp.entries_size = t->private->entries_size; |
| 1470 | tmp.valid_hooks = t->valid_hooks; |
| 1471 | } else { |
| 1472 | tmp.nentries = t->table->nentries; |
| 1473 | tmp.entries_size = t->table->entries_size; |
| 1474 | tmp.valid_hooks = t->table->valid_hooks; |
| 1475 | } |
Ingo Molnar | 57b47a5 | 2006-03-20 22:35:41 -0800 | [diff] [blame] | 1476 | mutex_unlock(&ebt_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1477 | if (copy_to_user(user, &tmp, *len) != 0){ |
| 1478 | BUGPRINT("c2u Didn't work\n"); |
| 1479 | ret = -EFAULT; |
| 1480 | break; |
| 1481 | } |
| 1482 | ret = 0; |
| 1483 | break; |
| 1484 | |
| 1485 | case EBT_SO_GET_ENTRIES: |
| 1486 | case EBT_SO_GET_INIT_ENTRIES: |
| 1487 | ret = copy_everything_to_user(t, user, len, cmd); |
Ingo Molnar | 57b47a5 | 2006-03-20 22:35:41 -0800 | [diff] [blame] | 1488 | mutex_unlock(&ebt_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1489 | break; |
| 1490 | |
| 1491 | default: |
Ingo Molnar | 57b47a5 | 2006-03-20 22:35:41 -0800 | [diff] [blame] | 1492 | mutex_unlock(&ebt_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1493 | ret = -EINVAL; |
| 1494 | } |
| 1495 | |
| 1496 | return ret; |
| 1497 | } |
| 1498 | |
| 1499 | static struct nf_sockopt_ops ebt_sockopts = |
Andrew Morton | 74ca4e5a | 2006-03-20 22:55:02 -0800 | [diff] [blame] | 1500 | { |
| 1501 | .pf = PF_INET, |
| 1502 | .set_optmin = EBT_BASE_CTL, |
| 1503 | .set_optmax = EBT_SO_SET_MAX + 1, |
| 1504 | .set = do_ebt_set_ctl, |
| 1505 | .get_optmin = EBT_BASE_CTL, |
| 1506 | .get_optmax = EBT_SO_GET_MAX + 1, |
| 1507 | .get = do_ebt_get_ctl, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1508 | }; |
| 1509 | |
Andrew Morton | 65b4b4e | 2006-03-28 16:37:06 -0800 | [diff] [blame] | 1510 | static int __init ebtables_init(void) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1511 | { |
| 1512 | int ret; |
| 1513 | |
Ingo Molnar | 57b47a5 | 2006-03-20 22:35:41 -0800 | [diff] [blame] | 1514 | mutex_lock(&ebt_mutex); |
Patrick McHardy | df0933d | 2006-09-20 11:57:53 -0700 | [diff] [blame] | 1515 | list_add(&ebt_standard_target.list, &ebt_targets); |
Ingo Molnar | 57b47a5 | 2006-03-20 22:35:41 -0800 | [diff] [blame] | 1516 | mutex_unlock(&ebt_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1517 | if ((ret = nf_register_sockopt(&ebt_sockopts)) < 0) |
| 1518 | return ret; |
| 1519 | |
| 1520 | printk(KERN_NOTICE "Ebtables v2.0 registered\n"); |
| 1521 | return 0; |
| 1522 | } |
| 1523 | |
Andrew Morton | 65b4b4e | 2006-03-28 16:37:06 -0800 | [diff] [blame] | 1524 | static void __exit ebtables_fini(void) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1525 | { |
| 1526 | nf_unregister_sockopt(&ebt_sockopts); |
| 1527 | printk(KERN_NOTICE "Ebtables v2.0 unregistered\n"); |
| 1528 | } |
| 1529 | |
| 1530 | EXPORT_SYMBOL(ebt_register_table); |
| 1531 | EXPORT_SYMBOL(ebt_unregister_table); |
| 1532 | EXPORT_SYMBOL(ebt_register_match); |
| 1533 | EXPORT_SYMBOL(ebt_unregister_match); |
| 1534 | EXPORT_SYMBOL(ebt_register_watcher); |
| 1535 | EXPORT_SYMBOL(ebt_unregister_watcher); |
| 1536 | EXPORT_SYMBOL(ebt_register_target); |
| 1537 | EXPORT_SYMBOL(ebt_unregister_target); |
| 1538 | EXPORT_SYMBOL(ebt_do_table); |
Andrew Morton | 65b4b4e | 2006-03-28 16:37:06 -0800 | [diff] [blame] | 1539 | module_init(ebtables_init); |
| 1540 | module_exit(ebtables_fini); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1541 | MODULE_LICENSE("GPL"); |