Patrick McHardy | c7232c9 | 2012-08-26 19:14:06 +0200 | [diff] [blame] | 1 | /* |
| 2 | * (C) 1999-2001 Paul `Rusty' Russell |
| 3 | * (C) 2002-2006 Netfilter Core Team <coreteam@netfilter.org> |
| 4 | * (C) 2011 Patrick McHardy <kaber@trash.net> |
| 5 | * |
| 6 | * This program is free software; you can redistribute it and/or modify |
| 7 | * it under the terms of the GNU General Public License version 2 as |
| 8 | * published by the Free Software Foundation. |
| 9 | */ |
| 10 | |
| 11 | #include <linux/module.h> |
| 12 | #include <linux/types.h> |
| 13 | #include <linux/timer.h> |
| 14 | #include <linux/skbuff.h> |
| 15 | #include <linux/gfp.h> |
| 16 | #include <net/xfrm.h> |
| 17 | #include <linux/jhash.h> |
| 18 | #include <linux/rtnetlink.h> |
| 19 | |
| 20 | #include <net/netfilter/nf_conntrack.h> |
| 21 | #include <net/netfilter/nf_conntrack_core.h> |
| 22 | #include <net/netfilter/nf_nat.h> |
| 23 | #include <net/netfilter/nf_nat_l3proto.h> |
| 24 | #include <net/netfilter/nf_nat_l4proto.h> |
| 25 | #include <net/netfilter/nf_nat_core.h> |
| 26 | #include <net/netfilter/nf_nat_helper.h> |
| 27 | #include <net/netfilter/nf_conntrack_helper.h> |
Patrick McHardy | 41d73ec | 2013-08-27 08:50:12 +0200 | [diff] [blame] | 28 | #include <net/netfilter/nf_conntrack_seqadj.h> |
Patrick McHardy | c7232c9 | 2012-08-26 19:14:06 +0200 | [diff] [blame] | 29 | #include <net/netfilter/nf_conntrack_l3proto.h> |
| 30 | #include <net/netfilter/nf_conntrack_zones.h> |
| 31 | #include <linux/netfilter/nf_nat.h> |
| 32 | |
| 33 | static DEFINE_SPINLOCK(nf_nat_lock); |
| 34 | |
| 35 | static DEFINE_MUTEX(nf_nat_proto_mutex); |
| 36 | static const struct nf_nat_l3proto __rcu *nf_nat_l3protos[NFPROTO_NUMPROTO] |
| 37 | __read_mostly; |
| 38 | static const struct nf_nat_l4proto __rcu **nf_nat_l4protos[NFPROTO_NUMPROTO] |
| 39 | __read_mostly; |
| 40 | |
| 41 | |
| 42 | inline const struct nf_nat_l3proto * |
| 43 | __nf_nat_l3proto_find(u8 family) |
| 44 | { |
| 45 | return rcu_dereference(nf_nat_l3protos[family]); |
| 46 | } |
| 47 | |
| 48 | inline const struct nf_nat_l4proto * |
| 49 | __nf_nat_l4proto_find(u8 family, u8 protonum) |
| 50 | { |
| 51 | return rcu_dereference(nf_nat_l4protos[family][protonum]); |
| 52 | } |
| 53 | EXPORT_SYMBOL_GPL(__nf_nat_l4proto_find); |
| 54 | |
| 55 | #ifdef CONFIG_XFRM |
| 56 | static void __nf_nat_decode_session(struct sk_buff *skb, struct flowi *fl) |
| 57 | { |
| 58 | const struct nf_nat_l3proto *l3proto; |
| 59 | const struct nf_conn *ct; |
| 60 | enum ip_conntrack_info ctinfo; |
| 61 | enum ip_conntrack_dir dir; |
| 62 | unsigned long statusbit; |
| 63 | u8 family; |
| 64 | |
| 65 | ct = nf_ct_get(skb, &ctinfo); |
| 66 | if (ct == NULL) |
| 67 | return; |
| 68 | |
| 69 | family = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.l3num; |
| 70 | rcu_read_lock(); |
| 71 | l3proto = __nf_nat_l3proto_find(family); |
| 72 | if (l3proto == NULL) |
| 73 | goto out; |
| 74 | |
| 75 | dir = CTINFO2DIR(ctinfo); |
| 76 | if (dir == IP_CT_DIR_ORIGINAL) |
| 77 | statusbit = IPS_DST_NAT; |
| 78 | else |
| 79 | statusbit = IPS_SRC_NAT; |
| 80 | |
| 81 | l3proto->decode_session(skb, ct, dir, statusbit, fl); |
| 82 | out: |
| 83 | rcu_read_unlock(); |
| 84 | } |
| 85 | |
| 86 | int nf_xfrm_me_harder(struct sk_buff *skb, unsigned int family) |
| 87 | { |
| 88 | struct flowi fl; |
| 89 | unsigned int hh_len; |
| 90 | struct dst_entry *dst; |
Patrick McHardy | aaa795a | 2013-04-05 06:41:12 +0000 | [diff] [blame] | 91 | int err; |
Patrick McHardy | c7232c9 | 2012-08-26 19:14:06 +0200 | [diff] [blame] | 92 | |
Patrick McHardy | aaa795a | 2013-04-05 06:41:12 +0000 | [diff] [blame] | 93 | err = xfrm_decode_session(skb, &fl, family); |
Dan Carpenter | e7e6f63 | 2013-04-24 05:11:51 +0000 | [diff] [blame] | 94 | if (err < 0) |
Patrick McHardy | aaa795a | 2013-04-05 06:41:12 +0000 | [diff] [blame] | 95 | return err; |
Patrick McHardy | c7232c9 | 2012-08-26 19:14:06 +0200 | [diff] [blame] | 96 | |
| 97 | dst = skb_dst(skb); |
| 98 | if (dst->xfrm) |
| 99 | dst = ((struct xfrm_dst *)dst)->route; |
| 100 | dst_hold(dst); |
| 101 | |
| 102 | dst = xfrm_lookup(dev_net(dst->dev), dst, &fl, skb->sk, 0); |
| 103 | if (IS_ERR(dst)) |
Patrick McHardy | aaa795a | 2013-04-05 06:41:12 +0000 | [diff] [blame] | 104 | return PTR_ERR(dst); |
Patrick McHardy | c7232c9 | 2012-08-26 19:14:06 +0200 | [diff] [blame] | 105 | |
| 106 | skb_dst_drop(skb); |
| 107 | skb_dst_set(skb, dst); |
| 108 | |
| 109 | /* Change in oif may mean change in hh_len. */ |
| 110 | hh_len = skb_dst(skb)->dev->hard_header_len; |
| 111 | if (skb_headroom(skb) < hh_len && |
| 112 | pskb_expand_head(skb, hh_len - skb_headroom(skb), 0, GFP_ATOMIC)) |
Patrick McHardy | aaa795a | 2013-04-05 06:41:12 +0000 | [diff] [blame] | 113 | return -ENOMEM; |
Patrick McHardy | c7232c9 | 2012-08-26 19:14:06 +0200 | [diff] [blame] | 114 | return 0; |
| 115 | } |
| 116 | EXPORT_SYMBOL(nf_xfrm_me_harder); |
| 117 | #endif /* CONFIG_XFRM */ |
| 118 | |
| 119 | /* We keep an extra hash for each conntrack, for fast searching. */ |
| 120 | static inline unsigned int |
| 121 | hash_by_src(const struct net *net, u16 zone, |
| 122 | const struct nf_conntrack_tuple *tuple) |
| 123 | { |
| 124 | unsigned int hash; |
| 125 | |
| 126 | /* Original src, to ensure we map it consistently if poss. */ |
| 127 | hash = jhash2((u32 *)&tuple->src, sizeof(tuple->src) / sizeof(u32), |
| 128 | tuple->dst.protonum ^ zone ^ nf_conntrack_hash_rnd); |
Daniel Borkmann | 8fc54f6 | 2014-08-23 20:58:54 +0200 | [diff] [blame] | 129 | |
| 130 | return reciprocal_scale(hash, net->ct.nat_htable_size); |
Patrick McHardy | c7232c9 | 2012-08-26 19:14:06 +0200 | [diff] [blame] | 131 | } |
| 132 | |
| 133 | /* Is this tuple already taken? (not by us) */ |
| 134 | int |
| 135 | nf_nat_used_tuple(const struct nf_conntrack_tuple *tuple, |
| 136 | const struct nf_conn *ignored_conntrack) |
| 137 | { |
| 138 | /* Conntrack tracking doesn't keep track of outgoing tuples; only |
| 139 | * incoming ones. NAT means they don't have a fixed mapping, |
| 140 | * so we invert the tuple and look for the incoming reply. |
| 141 | * |
| 142 | * We could keep a separate hash if this proves too slow. |
| 143 | */ |
| 144 | struct nf_conntrack_tuple reply; |
| 145 | |
| 146 | nf_ct_invert_tuplepr(&reply, tuple); |
| 147 | return nf_conntrack_tuple_taken(&reply, ignored_conntrack); |
| 148 | } |
| 149 | EXPORT_SYMBOL(nf_nat_used_tuple); |
| 150 | |
| 151 | /* If we source map this tuple so reply looks like reply_tuple, will |
| 152 | * that meet the constraints of range. |
| 153 | */ |
| 154 | static int in_range(const struct nf_nat_l3proto *l3proto, |
| 155 | const struct nf_nat_l4proto *l4proto, |
| 156 | const struct nf_conntrack_tuple *tuple, |
| 157 | const struct nf_nat_range *range) |
| 158 | { |
| 159 | /* If we are supposed to map IPs, then we must be in the |
| 160 | * range specified, otherwise let this drag us onto a new src IP. |
| 161 | */ |
| 162 | if (range->flags & NF_NAT_RANGE_MAP_IPS && |
| 163 | !l3proto->in_range(tuple, range)) |
| 164 | return 0; |
| 165 | |
| 166 | if (!(range->flags & NF_NAT_RANGE_PROTO_SPECIFIED) || |
| 167 | l4proto->in_range(tuple, NF_NAT_MANIP_SRC, |
| 168 | &range->min_proto, &range->max_proto)) |
| 169 | return 1; |
| 170 | |
| 171 | return 0; |
| 172 | } |
| 173 | |
| 174 | static inline int |
| 175 | same_src(const struct nf_conn *ct, |
| 176 | const struct nf_conntrack_tuple *tuple) |
| 177 | { |
| 178 | const struct nf_conntrack_tuple *t; |
| 179 | |
| 180 | t = &ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple; |
| 181 | return (t->dst.protonum == tuple->dst.protonum && |
| 182 | nf_inet_addr_cmp(&t->src.u3, &tuple->src.u3) && |
| 183 | t->src.u.all == tuple->src.u.all); |
| 184 | } |
| 185 | |
| 186 | /* Only called for SRC manip */ |
| 187 | static int |
| 188 | find_appropriate_src(struct net *net, u16 zone, |
| 189 | const struct nf_nat_l3proto *l3proto, |
| 190 | const struct nf_nat_l4proto *l4proto, |
| 191 | const struct nf_conntrack_tuple *tuple, |
| 192 | struct nf_conntrack_tuple *result, |
| 193 | const struct nf_nat_range *range) |
| 194 | { |
| 195 | unsigned int h = hash_by_src(net, zone, tuple); |
| 196 | const struct nf_conn_nat *nat; |
| 197 | const struct nf_conn *ct; |
Patrick McHardy | c7232c9 | 2012-08-26 19:14:06 +0200 | [diff] [blame] | 198 | |
Sasha Levin | b67bfe0 | 2013-02-27 17:06:00 -0800 | [diff] [blame] | 199 | hlist_for_each_entry_rcu(nat, &net->ct.nat_bysource[h], bysource) { |
Patrick McHardy | c7232c9 | 2012-08-26 19:14:06 +0200 | [diff] [blame] | 200 | ct = nat->ct; |
| 201 | if (same_src(ct, tuple) && nf_ct_zone(ct) == zone) { |
| 202 | /* Copy source part from reply tuple. */ |
| 203 | nf_ct_invert_tuplepr(result, |
| 204 | &ct->tuplehash[IP_CT_DIR_REPLY].tuple); |
| 205 | result->dst = tuple->dst; |
| 206 | |
Ulrich Weber | 136251d | 2012-09-20 03:52:04 +0000 | [diff] [blame] | 207 | if (in_range(l3proto, l4proto, result, range)) |
Patrick McHardy | c7232c9 | 2012-08-26 19:14:06 +0200 | [diff] [blame] | 208 | return 1; |
Patrick McHardy | c7232c9 | 2012-08-26 19:14:06 +0200 | [diff] [blame] | 209 | } |
| 210 | } |
| 211 | return 0; |
| 212 | } |
| 213 | |
| 214 | /* For [FUTURE] fragmentation handling, we want the least-used |
| 215 | * src-ip/dst-ip/proto triple. Fairness doesn't come into it. Thus |
| 216 | * if the range specifies 1.2.3.4 ports 10000-10005 and 1.2.3.5 ports |
| 217 | * 1-65535, we don't do pro-rata allocation based on ports; we choose |
| 218 | * the ip with the lowest src-ip/dst-ip/proto usage. |
| 219 | */ |
| 220 | static void |
| 221 | find_best_ips_proto(u16 zone, struct nf_conntrack_tuple *tuple, |
| 222 | const struct nf_nat_range *range, |
| 223 | const struct nf_conn *ct, |
| 224 | enum nf_nat_manip_type maniptype) |
| 225 | { |
| 226 | union nf_inet_addr *var_ipp; |
| 227 | unsigned int i, max; |
| 228 | /* Host order */ |
| 229 | u32 minip, maxip, j, dist; |
| 230 | bool full_range; |
| 231 | |
| 232 | /* No IP mapping? Do nothing. */ |
| 233 | if (!(range->flags & NF_NAT_RANGE_MAP_IPS)) |
| 234 | return; |
| 235 | |
| 236 | if (maniptype == NF_NAT_MANIP_SRC) |
| 237 | var_ipp = &tuple->src.u3; |
| 238 | else |
| 239 | var_ipp = &tuple->dst.u3; |
| 240 | |
| 241 | /* Fast path: only one choice. */ |
| 242 | if (nf_inet_addr_cmp(&range->min_addr, &range->max_addr)) { |
| 243 | *var_ipp = range->min_addr; |
| 244 | return; |
| 245 | } |
| 246 | |
| 247 | if (nf_ct_l3num(ct) == NFPROTO_IPV4) |
| 248 | max = sizeof(var_ipp->ip) / sizeof(u32) - 1; |
| 249 | else |
| 250 | max = sizeof(var_ipp->ip6) / sizeof(u32) - 1; |
| 251 | |
| 252 | /* Hashing source and destination IPs gives a fairly even |
| 253 | * spread in practice (if there are a small number of IPs |
| 254 | * involved, there usually aren't that many connections |
| 255 | * anyway). The consistency means that servers see the same |
| 256 | * client coming from the same IP (some Internet Banking sites |
| 257 | * like this), even across reboots. |
| 258 | */ |
Florian Westphal | 5693d68 | 2012-09-05 10:10:28 +0000 | [diff] [blame] | 259 | j = jhash2((u32 *)&tuple->src.u3, sizeof(tuple->src.u3) / sizeof(u32), |
Patrick McHardy | c7232c9 | 2012-08-26 19:14:06 +0200 | [diff] [blame] | 260 | range->flags & NF_NAT_RANGE_PERSISTENT ? |
| 261 | 0 : (__force u32)tuple->dst.u3.all[max] ^ zone); |
| 262 | |
| 263 | full_range = false; |
| 264 | for (i = 0; i <= max; i++) { |
| 265 | /* If first bytes of the address are at the maximum, use the |
| 266 | * distance. Otherwise use the full range. |
| 267 | */ |
| 268 | if (!full_range) { |
| 269 | minip = ntohl((__force __be32)range->min_addr.all[i]); |
| 270 | maxip = ntohl((__force __be32)range->max_addr.all[i]); |
| 271 | dist = maxip - minip + 1; |
| 272 | } else { |
| 273 | minip = 0; |
| 274 | dist = ~0; |
| 275 | } |
| 276 | |
| 277 | var_ipp->all[i] = (__force __u32) |
Daniel Borkmann | 8fc54f6 | 2014-08-23 20:58:54 +0200 | [diff] [blame] | 278 | htonl(minip + reciprocal_scale(j, dist)); |
Patrick McHardy | c7232c9 | 2012-08-26 19:14:06 +0200 | [diff] [blame] | 279 | if (var_ipp->all[i] != range->max_addr.all[i]) |
| 280 | full_range = true; |
| 281 | |
| 282 | if (!(range->flags & NF_NAT_RANGE_PERSISTENT)) |
| 283 | j ^= (__force u32)tuple->dst.u3.all[i]; |
| 284 | } |
| 285 | } |
| 286 | |
| 287 | /* Manipulate the tuple into the range given. For NF_INET_POST_ROUTING, |
| 288 | * we change the source to map into the range. For NF_INET_PRE_ROUTING |
| 289 | * and NF_INET_LOCAL_OUT, we change the destination to map into the |
| 290 | * range. It might not be possible to get a unique tuple, but we try. |
| 291 | * At worst (or if we race), we will end up with a final duplicate in |
| 292 | * __ip_conntrack_confirm and drop the packet. */ |
| 293 | static void |
| 294 | get_unique_tuple(struct nf_conntrack_tuple *tuple, |
| 295 | const struct nf_conntrack_tuple *orig_tuple, |
| 296 | const struct nf_nat_range *range, |
| 297 | struct nf_conn *ct, |
| 298 | enum nf_nat_manip_type maniptype) |
| 299 | { |
| 300 | const struct nf_nat_l3proto *l3proto; |
| 301 | const struct nf_nat_l4proto *l4proto; |
| 302 | struct net *net = nf_ct_net(ct); |
| 303 | u16 zone = nf_ct_zone(ct); |
| 304 | |
| 305 | rcu_read_lock(); |
| 306 | l3proto = __nf_nat_l3proto_find(orig_tuple->src.l3num); |
| 307 | l4proto = __nf_nat_l4proto_find(orig_tuple->src.l3num, |
| 308 | orig_tuple->dst.protonum); |
| 309 | |
| 310 | /* 1) If this srcip/proto/src-proto-part is currently mapped, |
| 311 | * and that same mapping gives a unique tuple within the given |
| 312 | * range, use that. |
| 313 | * |
| 314 | * This is only required for source (ie. NAT/masq) mappings. |
| 315 | * So far, we don't do local source mappings, so multiple |
| 316 | * manips not an issue. |
| 317 | */ |
| 318 | if (maniptype == NF_NAT_MANIP_SRC && |
Daniel Borkmann | 34ce324 | 2013-12-20 22:40:29 +0100 | [diff] [blame] | 319 | !(range->flags & NF_NAT_RANGE_PROTO_RANDOM_ALL)) { |
Patrick McHardy | c7232c9 | 2012-08-26 19:14:06 +0200 | [diff] [blame] | 320 | /* try the original tuple first */ |
| 321 | if (in_range(l3proto, l4proto, orig_tuple, range)) { |
| 322 | if (!nf_nat_used_tuple(orig_tuple, ct)) { |
| 323 | *tuple = *orig_tuple; |
| 324 | goto out; |
| 325 | } |
| 326 | } else if (find_appropriate_src(net, zone, l3proto, l4proto, |
| 327 | orig_tuple, tuple, range)) { |
| 328 | pr_debug("get_unique_tuple: Found current src map\n"); |
| 329 | if (!nf_nat_used_tuple(tuple, ct)) |
| 330 | goto out; |
| 331 | } |
| 332 | } |
| 333 | |
| 334 | /* 2) Select the least-used IP/proto combination in the given range */ |
| 335 | *tuple = *orig_tuple; |
| 336 | find_best_ips_proto(zone, tuple, range, ct, maniptype); |
| 337 | |
| 338 | /* 3) The per-protocol part of the manip is made to map into |
| 339 | * the range to make a unique tuple. |
| 340 | */ |
| 341 | |
| 342 | /* Only bother mapping if it's not already in range and unique */ |
Daniel Borkmann | 34ce324 | 2013-12-20 22:40:29 +0100 | [diff] [blame] | 343 | if (!(range->flags & NF_NAT_RANGE_PROTO_RANDOM_ALL)) { |
Patrick McHardy | c7232c9 | 2012-08-26 19:14:06 +0200 | [diff] [blame] | 344 | if (range->flags & NF_NAT_RANGE_PROTO_SPECIFIED) { |
| 345 | if (l4proto->in_range(tuple, maniptype, |
| 346 | &range->min_proto, |
| 347 | &range->max_proto) && |
| 348 | (range->min_proto.all == range->max_proto.all || |
| 349 | !nf_nat_used_tuple(tuple, ct))) |
| 350 | goto out; |
| 351 | } else if (!nf_nat_used_tuple(tuple, ct)) { |
| 352 | goto out; |
| 353 | } |
| 354 | } |
| 355 | |
| 356 | /* Last change: get protocol to try to obtain unique tuple. */ |
| 357 | l4proto->unique_tuple(l3proto, tuple, range, maniptype, ct); |
| 358 | out: |
| 359 | rcu_read_unlock(); |
| 360 | } |
| 361 | |
Florian Westphal | f768e5b | 2014-04-28 21:09:50 +0200 | [diff] [blame] | 362 | struct nf_conn_nat *nf_ct_nat_ext_add(struct nf_conn *ct) |
| 363 | { |
| 364 | struct nf_conn_nat *nat = nfct_nat(ct); |
| 365 | if (nat) |
| 366 | return nat; |
| 367 | |
| 368 | if (!nf_ct_is_confirmed(ct)) |
| 369 | nat = nf_ct_ext_add(ct, NF_CT_EXT_NAT, GFP_ATOMIC); |
| 370 | |
| 371 | return nat; |
| 372 | } |
| 373 | EXPORT_SYMBOL_GPL(nf_ct_nat_ext_add); |
| 374 | |
Patrick McHardy | c7232c9 | 2012-08-26 19:14:06 +0200 | [diff] [blame] | 375 | unsigned int |
| 376 | nf_nat_setup_info(struct nf_conn *ct, |
| 377 | const struct nf_nat_range *range, |
| 378 | enum nf_nat_manip_type maniptype) |
| 379 | { |
| 380 | struct net *net = nf_ct_net(ct); |
| 381 | struct nf_conntrack_tuple curr_tuple, new_tuple; |
| 382 | struct nf_conn_nat *nat; |
| 383 | |
| 384 | /* nat helper or nfctnetlink also setup binding */ |
Florian Westphal | f768e5b | 2014-04-28 21:09:50 +0200 | [diff] [blame] | 385 | nat = nf_ct_nat_ext_add(ct); |
| 386 | if (nat == NULL) |
| 387 | return NF_ACCEPT; |
Patrick McHardy | c7232c9 | 2012-08-26 19:14:06 +0200 | [diff] [blame] | 388 | |
| 389 | NF_CT_ASSERT(maniptype == NF_NAT_MANIP_SRC || |
| 390 | maniptype == NF_NAT_MANIP_DST); |
| 391 | BUG_ON(nf_nat_initialized(ct, maniptype)); |
| 392 | |
| 393 | /* What we've got will look like inverse of reply. Normally |
| 394 | * this is what is in the conntrack, except for prior |
| 395 | * manipulations (future optimization: if num_manips == 0, |
| 396 | * orig_tp = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple) |
| 397 | */ |
| 398 | nf_ct_invert_tuplepr(&curr_tuple, |
| 399 | &ct->tuplehash[IP_CT_DIR_REPLY].tuple); |
| 400 | |
| 401 | get_unique_tuple(&new_tuple, &curr_tuple, range, ct, maniptype); |
| 402 | |
| 403 | if (!nf_ct_tuple_equal(&new_tuple, &curr_tuple)) { |
| 404 | struct nf_conntrack_tuple reply; |
| 405 | |
| 406 | /* Alter conntrack table so will recognize replies. */ |
| 407 | nf_ct_invert_tuplepr(&reply, &new_tuple); |
| 408 | nf_conntrack_alter_reply(ct, &reply); |
| 409 | |
| 410 | /* Non-atomic: we own this at the moment. */ |
| 411 | if (maniptype == NF_NAT_MANIP_SRC) |
| 412 | ct->status |= IPS_SRC_NAT; |
| 413 | else |
| 414 | ct->status |= IPS_DST_NAT; |
Patrick McHardy | 41d73ec | 2013-08-27 08:50:12 +0200 | [diff] [blame] | 415 | |
| 416 | if (nfct_help(ct)) |
| 417 | nfct_seqadj_ext_add(ct); |
Patrick McHardy | c7232c9 | 2012-08-26 19:14:06 +0200 | [diff] [blame] | 418 | } |
| 419 | |
| 420 | if (maniptype == NF_NAT_MANIP_SRC) { |
| 421 | unsigned int srchash; |
| 422 | |
| 423 | srchash = hash_by_src(net, nf_ct_zone(ct), |
| 424 | &ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple); |
| 425 | spin_lock_bh(&nf_nat_lock); |
| 426 | /* nf_conntrack_alter_reply might re-allocate extension aera */ |
| 427 | nat = nfct_nat(ct); |
| 428 | nat->ct = ct; |
| 429 | hlist_add_head_rcu(&nat->bysource, |
| 430 | &net->ct.nat_bysource[srchash]); |
| 431 | spin_unlock_bh(&nf_nat_lock); |
| 432 | } |
| 433 | |
| 434 | /* It's done. */ |
| 435 | if (maniptype == NF_NAT_MANIP_DST) |
| 436 | ct->status |= IPS_DST_NAT_DONE; |
| 437 | else |
| 438 | ct->status |= IPS_SRC_NAT_DONE; |
| 439 | |
| 440 | return NF_ACCEPT; |
| 441 | } |
| 442 | EXPORT_SYMBOL(nf_nat_setup_info); |
| 443 | |
Pablo Neira Ayuso | 0eba801 | 2014-02-16 12:15:43 +0100 | [diff] [blame] | 444 | static unsigned int |
| 445 | __nf_nat_alloc_null_binding(struct nf_conn *ct, enum nf_nat_manip_type manip) |
Pablo Neira Ayuso | f59cb04 | 2013-10-14 10:57:04 +0200 | [diff] [blame] | 446 | { |
| 447 | /* Force range to this IP; let proto decide mapping for |
| 448 | * per-proto parts (hence not IP_NAT_RANGE_PROTO_SPECIFIED). |
| 449 | * Use reply in case it's already been mangled (eg local packet). |
| 450 | */ |
| 451 | union nf_inet_addr ip = |
Pablo Neira Ayuso | 0eba801 | 2014-02-16 12:15:43 +0100 | [diff] [blame] | 452 | (manip == NF_NAT_MANIP_SRC ? |
Pablo Neira Ayuso | f59cb04 | 2013-10-14 10:57:04 +0200 | [diff] [blame] | 453 | ct->tuplehash[IP_CT_DIR_REPLY].tuple.dst.u3 : |
| 454 | ct->tuplehash[IP_CT_DIR_REPLY].tuple.src.u3); |
| 455 | struct nf_nat_range range = { |
| 456 | .flags = NF_NAT_RANGE_MAP_IPS, |
| 457 | .min_addr = ip, |
| 458 | .max_addr = ip, |
| 459 | }; |
Pablo Neira Ayuso | 0eba801 | 2014-02-16 12:15:43 +0100 | [diff] [blame] | 460 | return nf_nat_setup_info(ct, &range, manip); |
| 461 | } |
| 462 | |
| 463 | unsigned int |
| 464 | nf_nat_alloc_null_binding(struct nf_conn *ct, unsigned int hooknum) |
| 465 | { |
| 466 | return __nf_nat_alloc_null_binding(ct, HOOK2MANIP(hooknum)); |
Pablo Neira Ayuso | f59cb04 | 2013-10-14 10:57:04 +0200 | [diff] [blame] | 467 | } |
| 468 | EXPORT_SYMBOL_GPL(nf_nat_alloc_null_binding); |
| 469 | |
Patrick McHardy | c7232c9 | 2012-08-26 19:14:06 +0200 | [diff] [blame] | 470 | /* Do packet manipulations according to nf_nat_setup_info. */ |
| 471 | unsigned int nf_nat_packet(struct nf_conn *ct, |
| 472 | enum ip_conntrack_info ctinfo, |
| 473 | unsigned int hooknum, |
| 474 | struct sk_buff *skb) |
| 475 | { |
| 476 | const struct nf_nat_l3proto *l3proto; |
| 477 | const struct nf_nat_l4proto *l4proto; |
| 478 | enum ip_conntrack_dir dir = CTINFO2DIR(ctinfo); |
| 479 | unsigned long statusbit; |
| 480 | enum nf_nat_manip_type mtype = HOOK2MANIP(hooknum); |
| 481 | |
| 482 | if (mtype == NF_NAT_MANIP_SRC) |
| 483 | statusbit = IPS_SRC_NAT; |
| 484 | else |
| 485 | statusbit = IPS_DST_NAT; |
| 486 | |
| 487 | /* Invert if this is reply dir. */ |
| 488 | if (dir == IP_CT_DIR_REPLY) |
| 489 | statusbit ^= IPS_NAT_MASK; |
| 490 | |
| 491 | /* Non-atomic: these bits don't change. */ |
| 492 | if (ct->status & statusbit) { |
| 493 | struct nf_conntrack_tuple target; |
| 494 | |
| 495 | /* We are aiming to look like inverse of other direction. */ |
| 496 | nf_ct_invert_tuplepr(&target, &ct->tuplehash[!dir].tuple); |
| 497 | |
| 498 | l3proto = __nf_nat_l3proto_find(target.src.l3num); |
| 499 | l4proto = __nf_nat_l4proto_find(target.src.l3num, |
| 500 | target.dst.protonum); |
| 501 | if (!l3proto->manip_pkt(skb, 0, l4proto, &target, mtype)) |
| 502 | return NF_DROP; |
| 503 | } |
| 504 | return NF_ACCEPT; |
| 505 | } |
| 506 | EXPORT_SYMBOL_GPL(nf_nat_packet); |
| 507 | |
| 508 | struct nf_nat_proto_clean { |
| 509 | u8 l3proto; |
| 510 | u8 l4proto; |
Patrick McHardy | c7232c9 | 2012-08-26 19:14:06 +0200 | [diff] [blame] | 511 | }; |
| 512 | |
Florian Westphal | c2d421e | 2013-04-11 04:22:39 +0000 | [diff] [blame] | 513 | /* kill conntracks with affected NAT section */ |
| 514 | static int nf_nat_proto_remove(struct nf_conn *i, void *data) |
Patrick McHardy | c7232c9 | 2012-08-26 19:14:06 +0200 | [diff] [blame] | 515 | { |
| 516 | const struct nf_nat_proto_clean *clean = data; |
| 517 | struct nf_conn_nat *nat = nfct_nat(i); |
| 518 | |
| 519 | if (!nat) |
| 520 | return 0; |
Florian Westphal | c2d421e | 2013-04-11 04:22:39 +0000 | [diff] [blame] | 521 | |
Patrick McHardy | c7232c9 | 2012-08-26 19:14:06 +0200 | [diff] [blame] | 522 | if ((clean->l3proto && nf_ct_l3num(i) != clean->l3proto) || |
| 523 | (clean->l4proto && nf_ct_protonum(i) != clean->l4proto)) |
| 524 | return 0; |
| 525 | |
Florian Westphal | c2d421e | 2013-04-11 04:22:39 +0000 | [diff] [blame] | 526 | return i->status & IPS_NAT_MASK ? 1 : 0; |
Patrick McHardy | c7232c9 | 2012-08-26 19:14:06 +0200 | [diff] [blame] | 527 | } |
| 528 | |
Florian Westphal | 945b2b2 | 2014-06-07 21:17:04 +0200 | [diff] [blame] | 529 | static int nf_nat_proto_clean(struct nf_conn *ct, void *data) |
| 530 | { |
| 531 | struct nf_conn_nat *nat = nfct_nat(ct); |
| 532 | |
| 533 | if (nf_nat_proto_remove(ct, data)) |
| 534 | return 1; |
| 535 | |
| 536 | if (!nat || !nat->ct) |
| 537 | return 0; |
| 538 | |
| 539 | /* This netns is being destroyed, and conntrack has nat null binding. |
| 540 | * Remove it from bysource hash, as the table will be freed soon. |
| 541 | * |
| 542 | * Else, when the conntrack is destoyed, nf_nat_cleanup_conntrack() |
| 543 | * will delete entry from already-freed table. |
| 544 | */ |
| 545 | if (!del_timer(&ct->timeout)) |
| 546 | return 1; |
| 547 | |
| 548 | spin_lock_bh(&nf_nat_lock); |
| 549 | hlist_del_rcu(&nat->bysource); |
| 550 | ct->status &= ~IPS_NAT_DONE_MASK; |
| 551 | nat->ct = NULL; |
| 552 | spin_unlock_bh(&nf_nat_lock); |
| 553 | |
| 554 | add_timer(&ct->timeout); |
| 555 | |
| 556 | /* don't delete conntrack. Although that would make things a lot |
| 557 | * simpler, we'd end up flushing all conntracks on nat rmmod. |
| 558 | */ |
| 559 | return 0; |
| 560 | } |
| 561 | |
Patrick McHardy | c7232c9 | 2012-08-26 19:14:06 +0200 | [diff] [blame] | 562 | static void nf_nat_l4proto_clean(u8 l3proto, u8 l4proto) |
| 563 | { |
| 564 | struct nf_nat_proto_clean clean = { |
| 565 | .l3proto = l3proto, |
| 566 | .l4proto = l4proto, |
| 567 | }; |
| 568 | struct net *net; |
| 569 | |
| 570 | rtnl_lock(); |
Patrick McHardy | c7232c9 | 2012-08-26 19:14:06 +0200 | [diff] [blame] | 571 | for_each_net(net) |
Florian Westphal | c655bc6 | 2013-07-29 15:41:55 +0200 | [diff] [blame] | 572 | nf_ct_iterate_cleanup(net, nf_nat_proto_remove, &clean, 0, 0); |
Patrick McHardy | c7232c9 | 2012-08-26 19:14:06 +0200 | [diff] [blame] | 573 | rtnl_unlock(); |
| 574 | } |
| 575 | |
| 576 | static void nf_nat_l3proto_clean(u8 l3proto) |
| 577 | { |
| 578 | struct nf_nat_proto_clean clean = { |
| 579 | .l3proto = l3proto, |
| 580 | }; |
| 581 | struct net *net; |
| 582 | |
| 583 | rtnl_lock(); |
Patrick McHardy | c7232c9 | 2012-08-26 19:14:06 +0200 | [diff] [blame] | 584 | |
Patrick McHardy | c7232c9 | 2012-08-26 19:14:06 +0200 | [diff] [blame] | 585 | for_each_net(net) |
Florian Westphal | c655bc6 | 2013-07-29 15:41:55 +0200 | [diff] [blame] | 586 | nf_ct_iterate_cleanup(net, nf_nat_proto_remove, &clean, 0, 0); |
Patrick McHardy | c7232c9 | 2012-08-26 19:14:06 +0200 | [diff] [blame] | 587 | rtnl_unlock(); |
| 588 | } |
| 589 | |
| 590 | /* Protocol registration. */ |
| 591 | int nf_nat_l4proto_register(u8 l3proto, const struct nf_nat_l4proto *l4proto) |
| 592 | { |
| 593 | const struct nf_nat_l4proto **l4protos; |
| 594 | unsigned int i; |
| 595 | int ret = 0; |
| 596 | |
| 597 | mutex_lock(&nf_nat_proto_mutex); |
| 598 | if (nf_nat_l4protos[l3proto] == NULL) { |
| 599 | l4protos = kmalloc(IPPROTO_MAX * sizeof(struct nf_nat_l4proto *), |
| 600 | GFP_KERNEL); |
| 601 | if (l4protos == NULL) { |
| 602 | ret = -ENOMEM; |
| 603 | goto out; |
| 604 | } |
| 605 | |
| 606 | for (i = 0; i < IPPROTO_MAX; i++) |
| 607 | RCU_INIT_POINTER(l4protos[i], &nf_nat_l4proto_unknown); |
| 608 | |
| 609 | /* Before making proto_array visible to lockless readers, |
| 610 | * we must make sure its content is committed to memory. |
| 611 | */ |
| 612 | smp_wmb(); |
| 613 | |
| 614 | nf_nat_l4protos[l3proto] = l4protos; |
| 615 | } |
| 616 | |
| 617 | if (rcu_dereference_protected( |
| 618 | nf_nat_l4protos[l3proto][l4proto->l4proto], |
| 619 | lockdep_is_held(&nf_nat_proto_mutex) |
| 620 | ) != &nf_nat_l4proto_unknown) { |
| 621 | ret = -EBUSY; |
| 622 | goto out; |
| 623 | } |
| 624 | RCU_INIT_POINTER(nf_nat_l4protos[l3proto][l4proto->l4proto], l4proto); |
| 625 | out: |
| 626 | mutex_unlock(&nf_nat_proto_mutex); |
| 627 | return ret; |
| 628 | } |
| 629 | EXPORT_SYMBOL_GPL(nf_nat_l4proto_register); |
| 630 | |
| 631 | /* No one stores the protocol anywhere; simply delete it. */ |
| 632 | void nf_nat_l4proto_unregister(u8 l3proto, const struct nf_nat_l4proto *l4proto) |
| 633 | { |
| 634 | mutex_lock(&nf_nat_proto_mutex); |
| 635 | RCU_INIT_POINTER(nf_nat_l4protos[l3proto][l4proto->l4proto], |
| 636 | &nf_nat_l4proto_unknown); |
| 637 | mutex_unlock(&nf_nat_proto_mutex); |
| 638 | synchronize_rcu(); |
| 639 | |
| 640 | nf_nat_l4proto_clean(l3proto, l4proto->l4proto); |
| 641 | } |
| 642 | EXPORT_SYMBOL_GPL(nf_nat_l4proto_unregister); |
| 643 | |
| 644 | int nf_nat_l3proto_register(const struct nf_nat_l3proto *l3proto) |
| 645 | { |
| 646 | int err; |
| 647 | |
| 648 | err = nf_ct_l3proto_try_module_get(l3proto->l3proto); |
| 649 | if (err < 0) |
| 650 | return err; |
| 651 | |
| 652 | mutex_lock(&nf_nat_proto_mutex); |
| 653 | RCU_INIT_POINTER(nf_nat_l4protos[l3proto->l3proto][IPPROTO_TCP], |
| 654 | &nf_nat_l4proto_tcp); |
| 655 | RCU_INIT_POINTER(nf_nat_l4protos[l3proto->l3proto][IPPROTO_UDP], |
| 656 | &nf_nat_l4proto_udp); |
| 657 | mutex_unlock(&nf_nat_proto_mutex); |
| 658 | |
| 659 | RCU_INIT_POINTER(nf_nat_l3protos[l3proto->l3proto], l3proto); |
| 660 | return 0; |
| 661 | } |
| 662 | EXPORT_SYMBOL_GPL(nf_nat_l3proto_register); |
| 663 | |
| 664 | void nf_nat_l3proto_unregister(const struct nf_nat_l3proto *l3proto) |
| 665 | { |
| 666 | mutex_lock(&nf_nat_proto_mutex); |
| 667 | RCU_INIT_POINTER(nf_nat_l3protos[l3proto->l3proto], NULL); |
| 668 | mutex_unlock(&nf_nat_proto_mutex); |
| 669 | synchronize_rcu(); |
| 670 | |
| 671 | nf_nat_l3proto_clean(l3proto->l3proto); |
| 672 | nf_ct_l3proto_module_put(l3proto->l3proto); |
| 673 | } |
| 674 | EXPORT_SYMBOL_GPL(nf_nat_l3proto_unregister); |
| 675 | |
| 676 | /* No one using conntrack by the time this called. */ |
| 677 | static void nf_nat_cleanup_conntrack(struct nf_conn *ct) |
| 678 | { |
| 679 | struct nf_conn_nat *nat = nf_ct_ext_find(ct, NF_CT_EXT_NAT); |
| 680 | |
| 681 | if (nat == NULL || nat->ct == NULL) |
| 682 | return; |
| 683 | |
| 684 | NF_CT_ASSERT(nat->ct->status & IPS_SRC_NAT_DONE); |
| 685 | |
| 686 | spin_lock_bh(&nf_nat_lock); |
| 687 | hlist_del_rcu(&nat->bysource); |
| 688 | spin_unlock_bh(&nf_nat_lock); |
| 689 | } |
| 690 | |
| 691 | static void nf_nat_move_storage(void *new, void *old) |
| 692 | { |
| 693 | struct nf_conn_nat *new_nat = new; |
| 694 | struct nf_conn_nat *old_nat = old; |
| 695 | struct nf_conn *ct = old_nat->ct; |
| 696 | |
| 697 | if (!ct || !(ct->status & IPS_SRC_NAT_DONE)) |
| 698 | return; |
| 699 | |
| 700 | spin_lock_bh(&nf_nat_lock); |
| 701 | hlist_replace_rcu(&old_nat->bysource, &new_nat->bysource); |
| 702 | spin_unlock_bh(&nf_nat_lock); |
| 703 | } |
| 704 | |
| 705 | static struct nf_ct_ext_type nat_extend __read_mostly = { |
| 706 | .len = sizeof(struct nf_conn_nat), |
| 707 | .align = __alignof__(struct nf_conn_nat), |
| 708 | .destroy = nf_nat_cleanup_conntrack, |
| 709 | .move = nf_nat_move_storage, |
| 710 | .id = NF_CT_EXT_NAT, |
| 711 | .flags = NF_CT_EXT_F_PREALLOC, |
| 712 | }; |
| 713 | |
Duan Jiong | 24de3d3 | 2014-06-30 09:19:32 +0800 | [diff] [blame] | 714 | #if IS_ENABLED(CONFIG_NF_CT_NETLINK) |
Patrick McHardy | c7232c9 | 2012-08-26 19:14:06 +0200 | [diff] [blame] | 715 | |
| 716 | #include <linux/netfilter/nfnetlink.h> |
| 717 | #include <linux/netfilter/nfnetlink_conntrack.h> |
| 718 | |
| 719 | static const struct nla_policy protonat_nla_policy[CTA_PROTONAT_MAX+1] = { |
| 720 | [CTA_PROTONAT_PORT_MIN] = { .type = NLA_U16 }, |
| 721 | [CTA_PROTONAT_PORT_MAX] = { .type = NLA_U16 }, |
| 722 | }; |
| 723 | |
| 724 | static int nfnetlink_parse_nat_proto(struct nlattr *attr, |
| 725 | const struct nf_conn *ct, |
| 726 | struct nf_nat_range *range) |
| 727 | { |
| 728 | struct nlattr *tb[CTA_PROTONAT_MAX+1]; |
| 729 | const struct nf_nat_l4proto *l4proto; |
| 730 | int err; |
| 731 | |
| 732 | err = nla_parse_nested(tb, CTA_PROTONAT_MAX, attr, protonat_nla_policy); |
| 733 | if (err < 0) |
| 734 | return err; |
| 735 | |
| 736 | l4proto = __nf_nat_l4proto_find(nf_ct_l3num(ct), nf_ct_protonum(ct)); |
| 737 | if (l4proto->nlattr_to_range) |
| 738 | err = l4proto->nlattr_to_range(tb, range); |
| 739 | |
| 740 | return err; |
| 741 | } |
| 742 | |
| 743 | static const struct nla_policy nat_nla_policy[CTA_NAT_MAX+1] = { |
| 744 | [CTA_NAT_V4_MINIP] = { .type = NLA_U32 }, |
| 745 | [CTA_NAT_V4_MAXIP] = { .type = NLA_U32 }, |
Patrick McHardy | 58a317f | 2012-08-26 19:14:12 +0200 | [diff] [blame] | 746 | [CTA_NAT_V6_MINIP] = { .len = sizeof(struct in6_addr) }, |
| 747 | [CTA_NAT_V6_MAXIP] = { .len = sizeof(struct in6_addr) }, |
Patrick McHardy | c7232c9 | 2012-08-26 19:14:06 +0200 | [diff] [blame] | 748 | [CTA_NAT_PROTO] = { .type = NLA_NESTED }, |
| 749 | }; |
| 750 | |
| 751 | static int |
| 752 | nfnetlink_parse_nat(const struct nlattr *nat, |
Pablo Neira Ayuso | 0eba801 | 2014-02-16 12:15:43 +0100 | [diff] [blame] | 753 | const struct nf_conn *ct, struct nf_nat_range *range, |
| 754 | const struct nf_nat_l3proto *l3proto) |
Patrick McHardy | c7232c9 | 2012-08-26 19:14:06 +0200 | [diff] [blame] | 755 | { |
Patrick McHardy | c7232c9 | 2012-08-26 19:14:06 +0200 | [diff] [blame] | 756 | struct nlattr *tb[CTA_NAT_MAX+1]; |
| 757 | int err; |
| 758 | |
| 759 | memset(range, 0, sizeof(*range)); |
| 760 | |
| 761 | err = nla_parse_nested(tb, CTA_NAT_MAX, nat, nat_nla_policy); |
| 762 | if (err < 0) |
| 763 | return err; |
| 764 | |
Patrick McHardy | c7232c9 | 2012-08-26 19:14:06 +0200 | [diff] [blame] | 765 | err = l3proto->nlattr_to_range(tb, range); |
| 766 | if (err < 0) |
Pablo Neira Ayuso | 0eba801 | 2014-02-16 12:15:43 +0100 | [diff] [blame] | 767 | return err; |
Patrick McHardy | c7232c9 | 2012-08-26 19:14:06 +0200 | [diff] [blame] | 768 | |
| 769 | if (!tb[CTA_NAT_PROTO]) |
Pablo Neira Ayuso | 0eba801 | 2014-02-16 12:15:43 +0100 | [diff] [blame] | 770 | return 0; |
Patrick McHardy | c7232c9 | 2012-08-26 19:14:06 +0200 | [diff] [blame] | 771 | |
Pablo Neira Ayuso | 0eba801 | 2014-02-16 12:15:43 +0100 | [diff] [blame] | 772 | return nfnetlink_parse_nat_proto(tb[CTA_NAT_PROTO], ct, range); |
Patrick McHardy | c7232c9 | 2012-08-26 19:14:06 +0200 | [diff] [blame] | 773 | } |
| 774 | |
Pablo Neira Ayuso | 0eba801 | 2014-02-16 12:15:43 +0100 | [diff] [blame] | 775 | /* This function is called under rcu_read_lock() */ |
Patrick McHardy | c7232c9 | 2012-08-26 19:14:06 +0200 | [diff] [blame] | 776 | static int |
| 777 | nfnetlink_parse_nat_setup(struct nf_conn *ct, |
| 778 | enum nf_nat_manip_type manip, |
| 779 | const struct nlattr *attr) |
| 780 | { |
| 781 | struct nf_nat_range range; |
Pablo Neira Ayuso | 0eba801 | 2014-02-16 12:15:43 +0100 | [diff] [blame] | 782 | const struct nf_nat_l3proto *l3proto; |
Patrick McHardy | c7232c9 | 2012-08-26 19:14:06 +0200 | [diff] [blame] | 783 | int err; |
| 784 | |
Pablo Neira Ayuso | 0eba801 | 2014-02-16 12:15:43 +0100 | [diff] [blame] | 785 | /* Should not happen, restricted to creating new conntracks |
| 786 | * via ctnetlink. |
| 787 | */ |
| 788 | if (WARN_ON_ONCE(nf_nat_initialized(ct, manip))) |
| 789 | return -EEXIST; |
| 790 | |
| 791 | /* Make sure that L3 NAT is there by when we call nf_nat_setup_info to |
| 792 | * attach the null binding, otherwise this may oops. |
| 793 | */ |
| 794 | l3proto = __nf_nat_l3proto_find(nf_ct_l3num(ct)); |
| 795 | if (l3proto == NULL) |
| 796 | return -EAGAIN; |
| 797 | |
| 798 | /* No NAT information has been passed, allocate the null-binding */ |
| 799 | if (attr == NULL) |
| 800 | return __nf_nat_alloc_null_binding(ct, manip); |
| 801 | |
| 802 | err = nfnetlink_parse_nat(attr, ct, &range, l3proto); |
Patrick McHardy | c7232c9 | 2012-08-26 19:14:06 +0200 | [diff] [blame] | 803 | if (err < 0) |
| 804 | return err; |
Patrick McHardy | c7232c9 | 2012-08-26 19:14:06 +0200 | [diff] [blame] | 805 | |
| 806 | return nf_nat_setup_info(ct, &range, manip); |
| 807 | } |
| 808 | #else |
| 809 | static int |
| 810 | nfnetlink_parse_nat_setup(struct nf_conn *ct, |
| 811 | enum nf_nat_manip_type manip, |
| 812 | const struct nlattr *attr) |
| 813 | { |
| 814 | return -EOPNOTSUPP; |
| 815 | } |
| 816 | #endif |
| 817 | |
| 818 | static int __net_init nf_nat_net_init(struct net *net) |
| 819 | { |
| 820 | /* Leave them the same for the moment. */ |
| 821 | net->ct.nat_htable_size = net->ct.htable_size; |
| 822 | net->ct.nat_bysource = nf_ct_alloc_hashtable(&net->ct.nat_htable_size, 0); |
| 823 | if (!net->ct.nat_bysource) |
| 824 | return -ENOMEM; |
| 825 | return 0; |
| 826 | } |
| 827 | |
| 828 | static void __net_exit nf_nat_net_exit(struct net *net) |
| 829 | { |
| 830 | struct nf_nat_proto_clean clean = {}; |
| 831 | |
Florian Westphal | 945b2b2 | 2014-06-07 21:17:04 +0200 | [diff] [blame] | 832 | nf_ct_iterate_cleanup(net, nf_nat_proto_clean, &clean, 0, 0); |
Patrick McHardy | c7232c9 | 2012-08-26 19:14:06 +0200 | [diff] [blame] | 833 | synchronize_rcu(); |
| 834 | nf_ct_free_hashtable(net->ct.nat_bysource, net->ct.nat_htable_size); |
| 835 | } |
| 836 | |
| 837 | static struct pernet_operations nf_nat_net_ops = { |
| 838 | .init = nf_nat_net_init, |
| 839 | .exit = nf_nat_net_exit, |
| 840 | }; |
| 841 | |
| 842 | static struct nf_ct_helper_expectfn follow_master_nat = { |
| 843 | .name = "nat-follow-master", |
| 844 | .expectfn = nf_nat_follow_master, |
| 845 | }; |
| 846 | |
Patrick McHardy | c7232c9 | 2012-08-26 19:14:06 +0200 | [diff] [blame] | 847 | static int __init nf_nat_init(void) |
| 848 | { |
| 849 | int ret; |
| 850 | |
| 851 | ret = nf_ct_extend_register(&nat_extend); |
| 852 | if (ret < 0) { |
| 853 | printk(KERN_ERR "nf_nat_core: Unable to register extension\n"); |
| 854 | return ret; |
| 855 | } |
| 856 | |
| 857 | ret = register_pernet_subsys(&nf_nat_net_ops); |
| 858 | if (ret < 0) |
| 859 | goto cleanup_extend; |
| 860 | |
| 861 | nf_ct_helper_expectfn_register(&follow_master_nat); |
| 862 | |
| 863 | /* Initialize fake conntrack so that NAT will skip it */ |
| 864 | nf_ct_untracked_status_or(IPS_NAT_DONE_MASK); |
| 865 | |
Patrick McHardy | c7232c9 | 2012-08-26 19:14:06 +0200 | [diff] [blame] | 866 | BUG_ON(nfnetlink_parse_nat_setup_hook != NULL); |
| 867 | RCU_INIT_POINTER(nfnetlink_parse_nat_setup_hook, |
| 868 | nfnetlink_parse_nat_setup); |
Patrick McHardy | c7232c9 | 2012-08-26 19:14:06 +0200 | [diff] [blame] | 869 | #ifdef CONFIG_XFRM |
| 870 | BUG_ON(nf_nat_decode_session_hook != NULL); |
| 871 | RCU_INIT_POINTER(nf_nat_decode_session_hook, __nf_nat_decode_session); |
| 872 | #endif |
| 873 | return 0; |
| 874 | |
| 875 | cleanup_extend: |
| 876 | nf_ct_extend_unregister(&nat_extend); |
| 877 | return ret; |
| 878 | } |
| 879 | |
| 880 | static void __exit nf_nat_cleanup(void) |
| 881 | { |
| 882 | unsigned int i; |
| 883 | |
| 884 | unregister_pernet_subsys(&nf_nat_net_ops); |
| 885 | nf_ct_extend_unregister(&nat_extend); |
| 886 | nf_ct_helper_expectfn_unregister(&follow_master_nat); |
Patrick McHardy | c7232c9 | 2012-08-26 19:14:06 +0200 | [diff] [blame] | 887 | RCU_INIT_POINTER(nfnetlink_parse_nat_setup_hook, NULL); |
Patrick McHardy | c7232c9 | 2012-08-26 19:14:06 +0200 | [diff] [blame] | 888 | #ifdef CONFIG_XFRM |
| 889 | RCU_INIT_POINTER(nf_nat_decode_session_hook, NULL); |
| 890 | #endif |
| 891 | for (i = 0; i < NFPROTO_NUMPROTO; i++) |
| 892 | kfree(nf_nat_l4protos[i]); |
| 893 | synchronize_net(); |
| 894 | } |
| 895 | |
| 896 | MODULE_LICENSE("GPL"); |
| 897 | |
| 898 | module_init(nf_nat_init); |
| 899 | module_exit(nf_nat_cleanup); |