| /* NAT for netfilter; shared with compatibility layer. */ |
| |
| /* (C) 1999-2001 Paul `Rusty' Russell |
| * (C) 2002-2004 Netfilter Core Team <coreteam@netfilter.org> |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License version 2 as |
| * published by the Free Software Foundation. |
| */ |
| |
| #include <linux/module.h> |
| #include <linux/types.h> |
| #include <linux/timer.h> |
| #include <linux/skbuff.h> |
| #include <linux/netfilter_ipv4.h> |
| #include <linux/vmalloc.h> |
| #include <net/checksum.h> |
| #include <net/icmp.h> |
| #include <net/ip.h> |
| #include <net/tcp.h> /* For tcp_prot in getorigdst */ |
| #include <linux/icmp.h> |
| #include <linux/udp.h> |
| #include <linux/jhash.h> |
| |
| #include <linux/netfilter_ipv4/ip_conntrack.h> |
| #include <linux/netfilter_ipv4/ip_conntrack_core.h> |
| #include <linux/netfilter_ipv4/ip_conntrack_protocol.h> |
| #include <linux/netfilter_ipv4/ip_nat.h> |
| #include <linux/netfilter_ipv4/ip_nat_protocol.h> |
| #include <linux/netfilter_ipv4/ip_nat_core.h> |
| #include <linux/netfilter_ipv4/ip_nat_helper.h> |
| #include <linux/netfilter_ipv4/ip_conntrack_helper.h> |
| |
| #if 0 |
| #define DEBUGP printk |
| #else |
| #define DEBUGP(format, args...) |
| #endif |
| |
| DEFINE_RWLOCK(ip_nat_lock); |
| |
| /* Calculated at init based on memory size */ |
| static unsigned int ip_nat_htable_size; |
| |
| static struct list_head *bysource; |
| |
| #define MAX_IP_NAT_PROTO 256 |
| static struct ip_nat_protocol *ip_nat_protos[MAX_IP_NAT_PROTO]; |
| |
| static inline struct ip_nat_protocol * |
| __ip_nat_proto_find(u_int8_t protonum) |
| { |
| return ip_nat_protos[protonum]; |
| } |
| |
| struct ip_nat_protocol * |
| ip_nat_proto_find_get(u_int8_t protonum) |
| { |
| struct ip_nat_protocol *p; |
| |
| /* we need to disable preemption to make sure 'p' doesn't get |
| * removed until we've grabbed the reference */ |
| preempt_disable(); |
| p = __ip_nat_proto_find(protonum); |
| if (!try_module_get(p->me)) |
| p = &ip_nat_unknown_protocol; |
| preempt_enable(); |
| |
| return p; |
| } |
| EXPORT_SYMBOL_GPL(ip_nat_proto_find_get); |
| |
| void |
| ip_nat_proto_put(struct ip_nat_protocol *p) |
| { |
| module_put(p->me); |
| } |
| EXPORT_SYMBOL_GPL(ip_nat_proto_put); |
| |
| /* We keep an extra hash for each conntrack, for fast searching. */ |
| static inline unsigned int |
| hash_by_src(const struct ip_conntrack_tuple *tuple) |
| { |
| /* Original src, to ensure we map it consistently if poss. */ |
| return jhash_3words((__force u32)tuple->src.ip, tuple->src.u.all, |
| tuple->dst.protonum, 0) % ip_nat_htable_size; |
| } |
| |
| /* Noone using conntrack by the time this called. */ |
| static void ip_nat_cleanup_conntrack(struct ip_conntrack *conn) |
| { |
| if (!(conn->status & IPS_NAT_DONE_MASK)) |
| return; |
| |
| write_lock_bh(&ip_nat_lock); |
| list_del(&conn->nat.info.bysource); |
| write_unlock_bh(&ip_nat_lock); |
| } |
| |
| /* Is this tuple already taken? (not by us) */ |
| int |
| ip_nat_used_tuple(const struct ip_conntrack_tuple *tuple, |
| const struct ip_conntrack *ignored_conntrack) |
| { |
| /* Conntrack tracking doesn't keep track of outgoing tuples; only |
| incoming ones. NAT means they don't have a fixed mapping, |
| so we invert the tuple and look for the incoming reply. |
| |
| We could keep a separate hash if this proves too slow. */ |
| struct ip_conntrack_tuple reply; |
| |
| invert_tuplepr(&reply, tuple); |
| return ip_conntrack_tuple_taken(&reply, ignored_conntrack); |
| } |
| EXPORT_SYMBOL(ip_nat_used_tuple); |
| |
| /* If we source map this tuple so reply looks like reply_tuple, will |
| * that meet the constraints of range. */ |
| static int |
| in_range(const struct ip_conntrack_tuple *tuple, |
| const struct ip_nat_range *range) |
| { |
| struct ip_nat_protocol *proto = |
| __ip_nat_proto_find(tuple->dst.protonum); |
| |
| /* If we are supposed to map IPs, then we must be in the |
| range specified, otherwise let this drag us onto a new src IP. */ |
| if (range->flags & IP_NAT_RANGE_MAP_IPS) { |
| if (ntohl(tuple->src.ip) < ntohl(range->min_ip) |
| || ntohl(tuple->src.ip) > ntohl(range->max_ip)) |
| return 0; |
| } |
| |
| if (!(range->flags & IP_NAT_RANGE_PROTO_SPECIFIED) |
| || proto->in_range(tuple, IP_NAT_MANIP_SRC, |
| &range->min, &range->max)) |
| return 1; |
| |
| return 0; |
| } |
| |
| static inline int |
| same_src(const struct ip_conntrack *ct, |
| const struct ip_conntrack_tuple *tuple) |
| { |
| return (ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.protonum |
| == tuple->dst.protonum |
| && ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.ip |
| == tuple->src.ip |
| && ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.u.all |
| == tuple->src.u.all); |
| } |
| |
| /* Only called for SRC manip */ |
| static int |
| find_appropriate_src(const struct ip_conntrack_tuple *tuple, |
| struct ip_conntrack_tuple *result, |
| const struct ip_nat_range *range) |
| { |
| unsigned int h = hash_by_src(tuple); |
| struct ip_conntrack *ct; |
| |
| read_lock_bh(&ip_nat_lock); |
| list_for_each_entry(ct, &bysource[h], nat.info.bysource) { |
| if (same_src(ct, tuple)) { |
| /* Copy source part from reply tuple. */ |
| invert_tuplepr(result, |
| &ct->tuplehash[IP_CT_DIR_REPLY].tuple); |
| result->dst = tuple->dst; |
| |
| if (in_range(result, range)) { |
| read_unlock_bh(&ip_nat_lock); |
| return 1; |
| } |
| } |
| } |
| read_unlock_bh(&ip_nat_lock); |
| return 0; |
| } |
| |
| /* For [FUTURE] fragmentation handling, we want the least-used |
| src-ip/dst-ip/proto triple. Fairness doesn't come into it. Thus |
| if the range specifies 1.2.3.4 ports 10000-10005 and 1.2.3.5 ports |
| 1-65535, we don't do pro-rata allocation based on ports; we choose |
| the ip with the lowest src-ip/dst-ip/proto usage. |
| */ |
| static void |
| find_best_ips_proto(struct ip_conntrack_tuple *tuple, |
| const struct ip_nat_range *range, |
| const struct ip_conntrack *conntrack, |
| enum ip_nat_manip_type maniptype) |
| { |
| __be32 *var_ipp; |
| /* Host order */ |
| u_int32_t minip, maxip, j; |
| |
| /* No IP mapping? Do nothing. */ |
| if (!(range->flags & IP_NAT_RANGE_MAP_IPS)) |
| return; |
| |
| if (maniptype == IP_NAT_MANIP_SRC) |
| var_ipp = &tuple->src.ip; |
| else |
| var_ipp = &tuple->dst.ip; |
| |
| /* Fast path: only one choice. */ |
| if (range->min_ip == range->max_ip) { |
| *var_ipp = range->min_ip; |
| return; |
| } |
| |
| /* Hashing source and destination IPs gives a fairly even |
| * spread in practice (if there are a small number of IPs |
| * involved, there usually aren't that many connections |
| * anyway). The consistency means that servers see the same |
| * client coming from the same IP (some Internet Banking sites |
| * like this), even across reboots. */ |
| minip = ntohl(range->min_ip); |
| maxip = ntohl(range->max_ip); |
| j = jhash_2words((__force u32)tuple->src.ip, (__force u32)tuple->dst.ip, 0); |
| *var_ipp = htonl(minip + j % (maxip - minip + 1)); |
| } |
| |
| /* Manipulate the tuple into the range given. For NF_IP_POST_ROUTING, |
| * we change the source to map into the range. For NF_IP_PRE_ROUTING |
| * and NF_IP_LOCAL_OUT, we change the destination to map into the |
| * range. It might not be possible to get a unique tuple, but we try. |
| * At worst (or if we race), we will end up with a final duplicate in |
| * __ip_conntrack_confirm and drop the packet. */ |
| static void |
| get_unique_tuple(struct ip_conntrack_tuple *tuple, |
| const struct ip_conntrack_tuple *orig_tuple, |
| const struct ip_nat_range *range, |
| struct ip_conntrack *conntrack, |
| enum ip_nat_manip_type maniptype) |
| { |
| struct ip_nat_protocol *proto; |
| |
| /* 1) If this srcip/proto/src-proto-part is currently mapped, |
| and that same mapping gives a unique tuple within the given |
| range, use that. |
| |
| This is only required for source (ie. NAT/masq) mappings. |
| So far, we don't do local source mappings, so multiple |
| manips not an issue. */ |
| if (maniptype == IP_NAT_MANIP_SRC) { |
| if (find_appropriate_src(orig_tuple, tuple, range)) { |
| DEBUGP("get_unique_tuple: Found current src map\n"); |
| if (!ip_nat_used_tuple(tuple, conntrack)) |
| return; |
| } |
| } |
| |
| /* 2) Select the least-used IP/proto combination in the given |
| range. */ |
| *tuple = *orig_tuple; |
| find_best_ips_proto(tuple, range, conntrack, maniptype); |
| |
| /* 3) The per-protocol part of the manip is made to map into |
| the range to make a unique tuple. */ |
| |
| proto = ip_nat_proto_find_get(orig_tuple->dst.protonum); |
| |
| /* Only bother mapping if it's not already in range and unique */ |
| if ((!(range->flags & IP_NAT_RANGE_PROTO_SPECIFIED) |
| || proto->in_range(tuple, maniptype, &range->min, &range->max)) |
| && !ip_nat_used_tuple(tuple, conntrack)) { |
| ip_nat_proto_put(proto); |
| return; |
| } |
| |
| /* Last change: get protocol to try to obtain unique tuple. */ |
| proto->unique_tuple(tuple, range, maniptype, conntrack); |
| |
| ip_nat_proto_put(proto); |
| } |
| |
| unsigned int |
| ip_nat_setup_info(struct ip_conntrack *conntrack, |
| const struct ip_nat_range *range, |
| unsigned int hooknum) |
| { |
| struct ip_conntrack_tuple curr_tuple, new_tuple; |
| struct ip_nat_info *info = &conntrack->nat.info; |
| int have_to_hash = !(conntrack->status & IPS_NAT_DONE_MASK); |
| enum ip_nat_manip_type maniptype = HOOK2MANIP(hooknum); |
| |
| IP_NF_ASSERT(hooknum == NF_IP_PRE_ROUTING |
| || hooknum == NF_IP_POST_ROUTING |
| || hooknum == NF_IP_LOCAL_IN |
| || hooknum == NF_IP_LOCAL_OUT); |
| BUG_ON(ip_nat_initialized(conntrack, maniptype)); |
| |
| /* What we've got will look like inverse of reply. Normally |
| this is what is in the conntrack, except for prior |
| manipulations (future optimization: if num_manips == 0, |
| orig_tp = |
| conntrack->tuplehash[IP_CT_DIR_ORIGINAL].tuple) */ |
| invert_tuplepr(&curr_tuple, |
| &conntrack->tuplehash[IP_CT_DIR_REPLY].tuple); |
| |
| get_unique_tuple(&new_tuple, &curr_tuple, range, conntrack, maniptype); |
| |
| if (!ip_ct_tuple_equal(&new_tuple, &curr_tuple)) { |
| struct ip_conntrack_tuple reply; |
| |
| /* Alter conntrack table so will recognize replies. */ |
| invert_tuplepr(&reply, &new_tuple); |
| ip_conntrack_alter_reply(conntrack, &reply); |
| |
| /* Non-atomic: we own this at the moment. */ |
| if (maniptype == IP_NAT_MANIP_SRC) |
| conntrack->status |= IPS_SRC_NAT; |
| else |
| conntrack->status |= IPS_DST_NAT; |
| } |
| |
| /* Place in source hash if this is the first time. */ |
| if (have_to_hash) { |
| unsigned int srchash |
| = hash_by_src(&conntrack->tuplehash[IP_CT_DIR_ORIGINAL] |
| .tuple); |
| write_lock_bh(&ip_nat_lock); |
| list_add(&info->bysource, &bysource[srchash]); |
| write_unlock_bh(&ip_nat_lock); |
| } |
| |
| /* It's done. */ |
| if (maniptype == IP_NAT_MANIP_DST) |
| set_bit(IPS_DST_NAT_DONE_BIT, &conntrack->status); |
| else |
| set_bit(IPS_SRC_NAT_DONE_BIT, &conntrack->status); |
| |
| return NF_ACCEPT; |
| } |
| EXPORT_SYMBOL(ip_nat_setup_info); |
| |
| /* Returns true if succeeded. */ |
| static int |
| manip_pkt(u_int16_t proto, |
| struct sk_buff **pskb, |
| unsigned int iphdroff, |
| const struct ip_conntrack_tuple *target, |
| enum ip_nat_manip_type maniptype) |
| { |
| struct iphdr *iph; |
| struct ip_nat_protocol *p; |
| |
| if (!skb_make_writable(pskb, iphdroff + sizeof(*iph))) |
| return 0; |
| |
| iph = (void *)(*pskb)->data + iphdroff; |
| |
| /* Manipulate protcol part. */ |
| p = ip_nat_proto_find_get(proto); |
| if (!p->manip_pkt(pskb, iphdroff, target, maniptype)) { |
| ip_nat_proto_put(p); |
| return 0; |
| } |
| ip_nat_proto_put(p); |
| |
| iph = (void *)(*pskb)->data + iphdroff; |
| |
| if (maniptype == IP_NAT_MANIP_SRC) { |
| nf_csum_replace4(&iph->check, iph->saddr, target->src.ip); |
| iph->saddr = target->src.ip; |
| } else { |
| nf_csum_replace4(&iph->check, iph->daddr, target->dst.ip); |
| iph->daddr = target->dst.ip; |
| } |
| return 1; |
| } |
| |
| /* Do packet manipulations according to ip_nat_setup_info. */ |
| unsigned int ip_nat_packet(struct ip_conntrack *ct, |
| enum ip_conntrack_info ctinfo, |
| unsigned int hooknum, |
| struct sk_buff **pskb) |
| { |
| enum ip_conntrack_dir dir = CTINFO2DIR(ctinfo); |
| unsigned long statusbit; |
| enum ip_nat_manip_type mtype = HOOK2MANIP(hooknum); |
| |
| if (mtype == IP_NAT_MANIP_SRC) |
| statusbit = IPS_SRC_NAT; |
| else |
| statusbit = IPS_DST_NAT; |
| |
| /* Invert if this is reply dir. */ |
| if (dir == IP_CT_DIR_REPLY) |
| statusbit ^= IPS_NAT_MASK; |
| |
| /* Non-atomic: these bits don't change. */ |
| if (ct->status & statusbit) { |
| struct ip_conntrack_tuple target; |
| |
| /* We are aiming to look like inverse of other direction. */ |
| invert_tuplepr(&target, &ct->tuplehash[!dir].tuple); |
| |
| if (!manip_pkt(target.dst.protonum, pskb, 0, &target, mtype)) |
| return NF_DROP; |
| } |
| return NF_ACCEPT; |
| } |
| EXPORT_SYMBOL_GPL(ip_nat_packet); |
| |
| /* Dir is direction ICMP is coming from (opposite to packet it contains) */ |
| int ip_nat_icmp_reply_translation(struct ip_conntrack *ct, |
| enum ip_conntrack_info ctinfo, |
| unsigned int hooknum, |
| struct sk_buff **pskb) |
| { |
| struct { |
| struct icmphdr icmp; |
| struct iphdr ip; |
| } *inside; |
| struct ip_conntrack_tuple inner, target; |
| int hdrlen = (*pskb)->nh.iph->ihl * 4; |
| enum ip_conntrack_dir dir = CTINFO2DIR(ctinfo); |
| unsigned long statusbit; |
| enum ip_nat_manip_type manip = HOOK2MANIP(hooknum); |
| |
| if (!skb_make_writable(pskb, hdrlen + sizeof(*inside))) |
| return 0; |
| |
| inside = (void *)(*pskb)->data + (*pskb)->nh.iph->ihl*4; |
| |
| /* We're actually going to mangle it beyond trivial checksum |
| adjustment, so make sure the current checksum is correct. */ |
| if (nf_ip_checksum(*pskb, hooknum, hdrlen, 0)) |
| return 0; |
| |
| /* Must be RELATED */ |
| IP_NF_ASSERT((*pskb)->nfctinfo == IP_CT_RELATED || |
| (*pskb)->nfctinfo == IP_CT_RELATED+IP_CT_IS_REPLY); |
| |
| /* Redirects on non-null nats must be dropped, else they'll |
| start talking to each other without our translation, and be |
| confused... --RR */ |
| if (inside->icmp.type == ICMP_REDIRECT) { |
| /* If NAT isn't finished, assume it and drop. */ |
| if ((ct->status & IPS_NAT_DONE_MASK) != IPS_NAT_DONE_MASK) |
| return 0; |
| |
| if (ct->status & IPS_NAT_MASK) |
| return 0; |
| } |
| |
| DEBUGP("icmp_reply_translation: translating error %p manp %u dir %s\n", |
| *pskb, manip, dir == IP_CT_DIR_ORIGINAL ? "ORIG" : "REPLY"); |
| |
| if (!ip_ct_get_tuple(&inside->ip, *pskb, (*pskb)->nh.iph->ihl*4 + |
| sizeof(struct icmphdr) + inside->ip.ihl*4, |
| &inner, |
| __ip_conntrack_proto_find(inside->ip.protocol))) |
| return 0; |
| |
| /* Change inner back to look like incoming packet. We do the |
| opposite manip on this hook to normal, because it might not |
| pass all hooks (locally-generated ICMP). Consider incoming |
| packet: PREROUTING (DST manip), routing produces ICMP, goes |
| through POSTROUTING (which must correct the DST manip). */ |
| if (!manip_pkt(inside->ip.protocol, pskb, |
| (*pskb)->nh.iph->ihl*4 |
| + sizeof(inside->icmp), |
| &ct->tuplehash[!dir].tuple, |
| !manip)) |
| return 0; |
| |
| if ((*pskb)->ip_summed != CHECKSUM_PARTIAL) { |
| /* Reloading "inside" here since manip_pkt inner. */ |
| inside = (void *)(*pskb)->data + (*pskb)->nh.iph->ihl*4; |
| inside->icmp.checksum = 0; |
| inside->icmp.checksum = csum_fold(skb_checksum(*pskb, hdrlen, |
| (*pskb)->len - hdrlen, |
| 0)); |
| } |
| |
| /* Change outer to look the reply to an incoming packet |
| * (proto 0 means don't invert per-proto part). */ |
| if (manip == IP_NAT_MANIP_SRC) |
| statusbit = IPS_SRC_NAT; |
| else |
| statusbit = IPS_DST_NAT; |
| |
| /* Invert if this is reply dir. */ |
| if (dir == IP_CT_DIR_REPLY) |
| statusbit ^= IPS_NAT_MASK; |
| |
| if (ct->status & statusbit) { |
| invert_tuplepr(&target, &ct->tuplehash[!dir].tuple); |
| if (!manip_pkt(0, pskb, 0, &target, manip)) |
| return 0; |
| } |
| |
| return 1; |
| } |
| EXPORT_SYMBOL_GPL(ip_nat_icmp_reply_translation); |
| |
| /* Protocol registration. */ |
| int ip_nat_protocol_register(struct ip_nat_protocol *proto) |
| { |
| int ret = 0; |
| |
| write_lock_bh(&ip_nat_lock); |
| if (ip_nat_protos[proto->protonum] != &ip_nat_unknown_protocol) { |
| ret = -EBUSY; |
| goto out; |
| } |
| ip_nat_protos[proto->protonum] = proto; |
| out: |
| write_unlock_bh(&ip_nat_lock); |
| return ret; |
| } |
| EXPORT_SYMBOL(ip_nat_protocol_register); |
| |
| /* Noone stores the protocol anywhere; simply delete it. */ |
| void ip_nat_protocol_unregister(struct ip_nat_protocol *proto) |
| { |
| write_lock_bh(&ip_nat_lock); |
| ip_nat_protos[proto->protonum] = &ip_nat_unknown_protocol; |
| write_unlock_bh(&ip_nat_lock); |
| |
| /* Someone could be still looking at the proto in a bh. */ |
| synchronize_net(); |
| } |
| EXPORT_SYMBOL(ip_nat_protocol_unregister); |
| |
| #if defined(CONFIG_IP_NF_CONNTRACK_NETLINK) || \ |
| defined(CONFIG_IP_NF_CONNTRACK_NETLINK_MODULE) |
| int |
| ip_nat_port_range_to_nfattr(struct sk_buff *skb, |
| const struct ip_nat_range *range) |
| { |
| NFA_PUT(skb, CTA_PROTONAT_PORT_MIN, sizeof(__be16), |
| &range->min.tcp.port); |
| NFA_PUT(skb, CTA_PROTONAT_PORT_MAX, sizeof(__be16), |
| &range->max.tcp.port); |
| |
| return 0; |
| |
| nfattr_failure: |
| return -1; |
| } |
| |
| int |
| ip_nat_port_nfattr_to_range(struct nfattr *tb[], struct ip_nat_range *range) |
| { |
| int ret = 0; |
| |
| /* we have to return whether we actually parsed something or not */ |
| |
| if (tb[CTA_PROTONAT_PORT_MIN-1]) { |
| ret = 1; |
| range->min.tcp.port = |
| *(__be16 *)NFA_DATA(tb[CTA_PROTONAT_PORT_MIN-1]); |
| } |
| |
| if (!tb[CTA_PROTONAT_PORT_MAX-1]) { |
| if (ret) |
| range->max.tcp.port = range->min.tcp.port; |
| } else { |
| ret = 1; |
| range->max.tcp.port = |
| *(__be16 *)NFA_DATA(tb[CTA_PROTONAT_PORT_MAX-1]); |
| } |
| |
| return ret; |
| } |
| EXPORT_SYMBOL_GPL(ip_nat_port_nfattr_to_range); |
| EXPORT_SYMBOL_GPL(ip_nat_port_range_to_nfattr); |
| #endif |
| |
| static int __init ip_nat_init(void) |
| { |
| size_t i; |
| |
| /* Leave them the same for the moment. */ |
| ip_nat_htable_size = ip_conntrack_htable_size; |
| |
| /* One vmalloc for both hash tables */ |
| bysource = vmalloc(sizeof(struct list_head) * ip_nat_htable_size); |
| if (!bysource) |
| return -ENOMEM; |
| |
| /* Sew in builtin protocols. */ |
| write_lock_bh(&ip_nat_lock); |
| for (i = 0; i < MAX_IP_NAT_PROTO; i++) |
| ip_nat_protos[i] = &ip_nat_unknown_protocol; |
| ip_nat_protos[IPPROTO_TCP] = &ip_nat_protocol_tcp; |
| ip_nat_protos[IPPROTO_UDP] = &ip_nat_protocol_udp; |
| ip_nat_protos[IPPROTO_ICMP] = &ip_nat_protocol_icmp; |
| write_unlock_bh(&ip_nat_lock); |
| |
| for (i = 0; i < ip_nat_htable_size; i++) { |
| INIT_LIST_HEAD(&bysource[i]); |
| } |
| |
| /* FIXME: Man, this is a hack. <SIGH> */ |
| IP_NF_ASSERT(ip_conntrack_destroyed == NULL); |
| ip_conntrack_destroyed = &ip_nat_cleanup_conntrack; |
| |
| /* Initialize fake conntrack so that NAT will skip it */ |
| ip_conntrack_untracked.status |= IPS_NAT_DONE_MASK; |
| return 0; |
| } |
| |
| /* Clear NAT section of all conntracks, in case we're loaded again. */ |
| static int clean_nat(struct ip_conntrack *i, void *data) |
| { |
| memset(&i->nat, 0, sizeof(i->nat)); |
| i->status &= ~(IPS_NAT_MASK | IPS_NAT_DONE_MASK | IPS_SEQ_ADJUST); |
| return 0; |
| } |
| |
| static void __exit ip_nat_cleanup(void) |
| { |
| ip_ct_iterate_cleanup(&clean_nat, NULL); |
| ip_conntrack_destroyed = NULL; |
| vfree(bysource); |
| } |
| |
| MODULE_LICENSE("GPL"); |
| |
| module_init(ip_nat_init); |
| module_exit(ip_nat_cleanup); |