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@@ -0,0 +1,647 @@
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+/* NAT for netfilter; shared with compatibility layer. */
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+
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+/* (C) 1999-2001 Paul `Rusty' Russell
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+ * (C) 2002-2006 Netfilter Core Team <coreteam@netfilter.org>
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+ *
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+ * This program is free software; you can redistribute it and/or modify
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+ * it under the terms of the GNU General Public License version 2 as
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+ * published by the Free Software Foundation.
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+ */
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+
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+#include <linux/module.h>
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+#include <linux/types.h>
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+#include <linux/timer.h>
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+#include <linux/skbuff.h>
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+#include <linux/vmalloc.h>
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+#include <net/checksum.h>
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+#include <net/icmp.h>
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+#include <net/ip.h>
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+#include <net/tcp.h> /* For tcp_prot in getorigdst */
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+#include <linux/icmp.h>
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+#include <linux/udp.h>
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+#include <linux/jhash.h>
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+
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+#include <linux/netfilter_ipv4.h>
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+#include <net/netfilter/nf_conntrack.h>
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+#include <net/netfilter/nf_conntrack_core.h>
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+#include <net/netfilter/nf_nat.h>
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+#include <net/netfilter/nf_nat_protocol.h>
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+#include <net/netfilter/nf_nat_core.h>
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+#include <net/netfilter/nf_nat_helper.h>
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+#include <net/netfilter/nf_conntrack_helper.h>
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+#include <net/netfilter/nf_conntrack_l3proto.h>
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+#include <net/netfilter/nf_conntrack_l4proto.h>
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+
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+#if 0
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+#define DEBUGP printk
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+#else
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+#define DEBUGP(format, args...)
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+#endif
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+
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+static DEFINE_RWLOCK(nf_nat_lock);
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+
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+static struct nf_conntrack_l3proto *l3proto = NULL;
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+
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+/* Calculated at init based on memory size */
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+static unsigned int nf_nat_htable_size;
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+
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+static struct list_head *bysource;
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+
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+#define MAX_IP_NAT_PROTO 256
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+static struct nf_nat_protocol *nf_nat_protos[MAX_IP_NAT_PROTO];
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+
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+static inline struct nf_nat_protocol *
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+__nf_nat_proto_find(u_int8_t protonum)
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+{
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+ return nf_nat_protos[protonum];
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+}
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+
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+struct nf_nat_protocol *
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+nf_nat_proto_find_get(u_int8_t protonum)
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+{
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+ struct nf_nat_protocol *p;
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+
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+ /* we need to disable preemption to make sure 'p' doesn't get
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+ * removed until we've grabbed the reference */
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+ preempt_disable();
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+ p = __nf_nat_proto_find(protonum);
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+ if (!try_module_get(p->me))
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+ p = &nf_nat_unknown_protocol;
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+ preempt_enable();
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+
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+ return p;
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+}
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+EXPORT_SYMBOL_GPL(nf_nat_proto_find_get);
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+
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+void
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+nf_nat_proto_put(struct nf_nat_protocol *p)
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+{
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+ module_put(p->me);
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+}
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+EXPORT_SYMBOL_GPL(nf_nat_proto_put);
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+
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+/* We keep an extra hash for each conntrack, for fast searching. */
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+static inline unsigned int
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+hash_by_src(const struct nf_conntrack_tuple *tuple)
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+{
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+ /* Original src, to ensure we map it consistently if poss. */
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+ return jhash_3words((__force u32)tuple->src.u3.ip, tuple->src.u.all,
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+ tuple->dst.protonum, 0) % nf_nat_htable_size;
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+}
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+
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+/* Noone using conntrack by the time this called. */
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+static void nf_nat_cleanup_conntrack(struct nf_conn *conn)
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+{
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+ struct nf_conn_nat *nat;
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+ if (!(conn->status & IPS_NAT_DONE_MASK))
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+ return;
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+
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+ nat = nfct_nat(conn);
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+ write_lock_bh(&nf_nat_lock);
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+ list_del(&nat->info.bysource);
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+ write_unlock_bh(&nf_nat_lock);
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+}
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+
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+/* Is this tuple already taken? (not by us) */
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+int
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+nf_nat_used_tuple(const struct nf_conntrack_tuple *tuple,
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+ const struct nf_conn *ignored_conntrack)
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+{
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+ /* Conntrack tracking doesn't keep track of outgoing tuples; only
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+ incoming ones. NAT means they don't have a fixed mapping,
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+ so we invert the tuple and look for the incoming reply.
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+
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+ We could keep a separate hash if this proves too slow. */
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+ struct nf_conntrack_tuple reply;
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+
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+ nf_ct_invert_tuplepr(&reply, tuple);
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+ return nf_conntrack_tuple_taken(&reply, ignored_conntrack);
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+}
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+EXPORT_SYMBOL(nf_nat_used_tuple);
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+
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+/* If we source map this tuple so reply looks like reply_tuple, will
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+ * that meet the constraints of range. */
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+static int
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+in_range(const struct nf_conntrack_tuple *tuple,
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+ const struct nf_nat_range *range)
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+{
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+ struct nf_nat_protocol *proto;
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+
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+ proto = __nf_nat_proto_find(tuple->dst.protonum);
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+ /* If we are supposed to map IPs, then we must be in the
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+ range specified, otherwise let this drag us onto a new src IP. */
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+ if (range->flags & IP_NAT_RANGE_MAP_IPS) {
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+ if (ntohl(tuple->src.u3.ip) < ntohl(range->min_ip) ||
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+ ntohl(tuple->src.u3.ip) > ntohl(range->max_ip))
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+ return 0;
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+ }
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+
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+ if (!(range->flags & IP_NAT_RANGE_PROTO_SPECIFIED) ||
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+ proto->in_range(tuple, IP_NAT_MANIP_SRC,
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+ &range->min, &range->max))
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+ return 1;
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+
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+ return 0;
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+}
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+
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+static inline int
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+same_src(const struct nf_conn *ct,
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+ const struct nf_conntrack_tuple *tuple)
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+{
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+ const struct nf_conntrack_tuple *t;
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+
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+ t = &ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple;
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+ return (t->dst.protonum == tuple->dst.protonum &&
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+ t->src.u3.ip == tuple->src.u3.ip &&
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+ t->src.u.all == tuple->src.u.all);
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+}
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+
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+/* Only called for SRC manip */
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+static int
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+find_appropriate_src(const struct nf_conntrack_tuple *tuple,
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+ struct nf_conntrack_tuple *result,
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+ const struct nf_nat_range *range)
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+{
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+ unsigned int h = hash_by_src(tuple);
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+ struct nf_conn_nat *nat;
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+ struct nf_conn *ct;
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+
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+ read_lock_bh(&nf_nat_lock);
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+ list_for_each_entry(nat, &bysource[h], info.bysource) {
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+ ct = (struct nf_conn *)((char *)nat - offsetof(struct nf_conn, data));
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+ if (same_src(ct, tuple)) {
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+ /* Copy source part from reply tuple. */
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+ nf_ct_invert_tuplepr(result,
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+ &ct->tuplehash[IP_CT_DIR_REPLY].tuple);
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+ result->dst = tuple->dst;
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+
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+ if (in_range(result, range)) {
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+ read_unlock_bh(&nf_nat_lock);
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+ return 1;
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+ }
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+ }
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+ }
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+ read_unlock_bh(&nf_nat_lock);
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+ return 0;
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+}
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+
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+/* For [FUTURE] fragmentation handling, we want the least-used
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+ src-ip/dst-ip/proto triple. Fairness doesn't come into it. Thus
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+ if the range specifies 1.2.3.4 ports 10000-10005 and 1.2.3.5 ports
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+ 1-65535, we don't do pro-rata allocation based on ports; we choose
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+ the ip with the lowest src-ip/dst-ip/proto usage.
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+*/
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+static void
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+find_best_ips_proto(struct nf_conntrack_tuple *tuple,
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+ const struct nf_nat_range *range,
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+ const struct nf_conn *ct,
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+ enum nf_nat_manip_type maniptype)
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+{
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+ __be32 *var_ipp;
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+ /* Host order */
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+ u_int32_t minip, maxip, j;
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+
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+ /* No IP mapping? Do nothing. */
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+ if (!(range->flags & IP_NAT_RANGE_MAP_IPS))
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+ return;
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+
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+ if (maniptype == IP_NAT_MANIP_SRC)
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+ var_ipp = &tuple->src.u3.ip;
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+ else
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+ var_ipp = &tuple->dst.u3.ip;
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+
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+ /* Fast path: only one choice. */
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+ if (range->min_ip == range->max_ip) {
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+ *var_ipp = range->min_ip;
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+ return;
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+ }
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+
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+ /* Hashing source and destination IPs gives a fairly even
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+ * spread in practice (if there are a small number of IPs
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+ * involved, there usually aren't that many connections
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+ * anyway). The consistency means that servers see the same
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+ * client coming from the same IP (some Internet Banking sites
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+ * like this), even across reboots. */
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+ minip = ntohl(range->min_ip);
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+ maxip = ntohl(range->max_ip);
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+ j = jhash_2words((__force u32)tuple->src.u3.ip,
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+ (__force u32)tuple->dst.u3.ip, 0);
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+ *var_ipp = htonl(minip + j % (maxip - minip + 1));
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+}
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+
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+/* Manipulate the tuple into the range given. For NF_IP_POST_ROUTING,
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+ * we change the source to map into the range. For NF_IP_PRE_ROUTING
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+ * and NF_IP_LOCAL_OUT, we change the destination to map into the
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+ * range. It might not be possible to get a unique tuple, but we try.
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+ * At worst (or if we race), we will end up with a final duplicate in
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+ * __ip_conntrack_confirm and drop the packet. */
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+static void
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+get_unique_tuple(struct nf_conntrack_tuple *tuple,
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+ const struct nf_conntrack_tuple *orig_tuple,
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+ const struct nf_nat_range *range,
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+ struct nf_conn *ct,
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+ enum nf_nat_manip_type maniptype)
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+{
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+ struct nf_nat_protocol *proto;
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+
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+ /* 1) If this srcip/proto/src-proto-part is currently mapped,
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+ and that same mapping gives a unique tuple within the given
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+ range, use that.
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+
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+ This is only required for source (ie. NAT/masq) mappings.
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+ So far, we don't do local source mappings, so multiple
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+ manips not an issue. */
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+ if (maniptype == IP_NAT_MANIP_SRC) {
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+ if (find_appropriate_src(orig_tuple, tuple, range)) {
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+ DEBUGP("get_unique_tuple: Found current src map\n");
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+ if (!nf_nat_used_tuple(tuple, ct))
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+ return;
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+ }
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+ }
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+
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+ /* 2) Select the least-used IP/proto combination in the given
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+ range. */
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+ *tuple = *orig_tuple;
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+ find_best_ips_proto(tuple, range, ct, maniptype);
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+
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+ /* 3) The per-protocol part of the manip is made to map into
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+ the range to make a unique tuple. */
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+
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+ proto = nf_nat_proto_find_get(orig_tuple->dst.protonum);
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+
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+ /* Only bother mapping if it's not already in range and unique */
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+ if ((!(range->flags & IP_NAT_RANGE_PROTO_SPECIFIED) ||
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+ proto->in_range(tuple, maniptype, &range->min, &range->max)) &&
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+ !nf_nat_used_tuple(tuple, ct)) {
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+ nf_nat_proto_put(proto);
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+ return;
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+ }
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+
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+ /* Last change: get protocol to try to obtain unique tuple. */
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+ proto->unique_tuple(tuple, range, maniptype, ct);
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+
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+ nf_nat_proto_put(proto);
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+}
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+
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+unsigned int
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+nf_nat_setup_info(struct nf_conn *ct,
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+ const struct nf_nat_range *range,
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+ unsigned int hooknum)
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+{
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+ struct nf_conntrack_tuple curr_tuple, new_tuple;
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+ struct nf_conn_nat *nat = nfct_nat(ct);
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+ struct nf_nat_info *info = &nat->info;
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+ int have_to_hash = !(ct->status & IPS_NAT_DONE_MASK);
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+ enum nf_nat_manip_type maniptype = HOOK2MANIP(hooknum);
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+
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+ NF_CT_ASSERT(hooknum == NF_IP_PRE_ROUTING ||
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+ hooknum == NF_IP_POST_ROUTING ||
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+ hooknum == NF_IP_LOCAL_IN ||
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+ hooknum == NF_IP_LOCAL_OUT);
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+ BUG_ON(nf_nat_initialized(ct, maniptype));
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+
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+ /* What we've got will look like inverse of reply. Normally
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+ this is what is in the conntrack, except for prior
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+ manipulations (future optimization: if num_manips == 0,
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+ orig_tp =
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+ conntrack->tuplehash[IP_CT_DIR_ORIGINAL].tuple) */
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+ nf_ct_invert_tuplepr(&curr_tuple,
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+ &ct->tuplehash[IP_CT_DIR_REPLY].tuple);
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+
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+ get_unique_tuple(&new_tuple, &curr_tuple, range, ct, maniptype);
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+
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+ if (!nf_ct_tuple_equal(&new_tuple, &curr_tuple)) {
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+ struct nf_conntrack_tuple reply;
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+
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+ /* Alter conntrack table so will recognize replies. */
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+ nf_ct_invert_tuplepr(&reply, &new_tuple);
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+ nf_conntrack_alter_reply(ct, &reply);
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+
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+ /* Non-atomic: we own this at the moment. */
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+ if (maniptype == IP_NAT_MANIP_SRC)
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+ ct->status |= IPS_SRC_NAT;
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+ else
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+ ct->status |= IPS_DST_NAT;
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+ }
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+
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+ /* Place in source hash if this is the first time. */
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+ if (have_to_hash) {
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+ unsigned int srchash;
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+
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+ srchash = hash_by_src(&ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple);
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+ write_lock_bh(&nf_nat_lock);
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+ list_add(&info->bysource, &bysource[srchash]);
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+ write_unlock_bh(&nf_nat_lock);
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+ }
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+
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+ /* It's done. */
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+ if (maniptype == IP_NAT_MANIP_DST)
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+ set_bit(IPS_DST_NAT_DONE_BIT, &ct->status);
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+ else
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+ set_bit(IPS_SRC_NAT_DONE_BIT, &ct->status);
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+
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+ return NF_ACCEPT;
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+}
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+EXPORT_SYMBOL(nf_nat_setup_info);
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+
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+/* Returns true if succeeded. */
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+static int
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+manip_pkt(u_int16_t proto,
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+ struct sk_buff **pskb,
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+ unsigned int iphdroff,
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+ const struct nf_conntrack_tuple *target,
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+ enum nf_nat_manip_type maniptype)
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+{
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+ struct iphdr *iph;
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+ struct nf_nat_protocol *p;
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+
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+ if (!skb_make_writable(pskb, iphdroff + sizeof(*iph)))
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+ return 0;
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+
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+ iph = (void *)(*pskb)->data + iphdroff;
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+
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+ /* Manipulate protcol part. */
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+ p = nf_nat_proto_find_get(proto);
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+ if (!p->manip_pkt(pskb, iphdroff, target, maniptype)) {
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+ nf_nat_proto_put(p);
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+ return 0;
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+ }
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+ nf_nat_proto_put(p);
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+
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+ iph = (void *)(*pskb)->data + iphdroff;
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+
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+ if (maniptype == IP_NAT_MANIP_SRC) {
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+ nf_csum_replace4(&iph->check, iph->saddr, target->src.u3.ip);
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+ iph->saddr = target->src.u3.ip;
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+ } else {
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+ nf_csum_replace4(&iph->check, iph->daddr, target->dst.u3.ip);
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+ iph->daddr = target->dst.u3.ip;
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+ }
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|
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+ return 1;
|
|
|
+}
|
|
|
+
|
|
|
+/* Do packet manipulations according to nf_nat_setup_info. */
|
|
|
+unsigned int nf_nat_packet(struct nf_conn *ct,
|
|
|
+ enum ip_conntrack_info ctinfo,
|
|
|
+ unsigned int hooknum,
|
|
|
+ struct sk_buff **pskb)
|
|
|
+{
|
|
|
+ enum ip_conntrack_dir dir = CTINFO2DIR(ctinfo);
|
|
|
+ unsigned long statusbit;
|
|
|
+ enum nf_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 nf_conntrack_tuple target;
|
|
|
+
|
|
|
+ /* We are aiming to look like inverse of other direction. */
|
|
|
+ nf_ct_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(nf_nat_packet);
|
|
|
+
|
|
|
+/* Dir is direction ICMP is coming from (opposite to packet it contains) */
|
|
|
+int nf_nat_icmp_reply_translation(struct nf_conn *ct,
|
|
|
+ enum ip_conntrack_info ctinfo,
|
|
|
+ unsigned int hooknum,
|
|
|
+ struct sk_buff **pskb)
|
|
|
+{
|
|
|
+ struct {
|
|
|
+ struct icmphdr icmp;
|
|
|
+ struct iphdr ip;
|
|
|
+ } *inside;
|
|
|
+ struct nf_conntrack_tuple inner, target;
|
|
|
+ int hdrlen = (*pskb)->nh.iph->ihl * 4;
|
|
|
+ enum ip_conntrack_dir dir = CTINFO2DIR(ctinfo);
|
|
|
+ unsigned long statusbit;
|
|
|
+ enum nf_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 */
|
|
|
+ NF_CT_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 (!nf_ct_get_tuple(*pskb,
|
|
|
+ (*pskb)->nh.iph->ihl*4 + sizeof(struct icmphdr),
|
|
|
+ (*pskb)->nh.iph->ihl*4 +
|
|
|
+ sizeof(struct icmphdr) + inside->ip.ihl*4,
|
|
|
+ (u_int16_t)AF_INET,
|
|
|
+ inside->ip.protocol,
|
|
|
+ &inner,
|
|
|
+ l3proto,
|
|
|
+ __nf_ct_l4proto_find((u_int16_t)PF_INET,
|
|
|
+ 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) {
|
|
|
+ nf_ct_invert_tuplepr(&target, &ct->tuplehash[!dir].tuple);
|
|
|
+ if (!manip_pkt(0, pskb, 0, &target, manip))
|
|
|
+ return 0;
|
|
|
+ }
|
|
|
+
|
|
|
+ return 1;
|
|
|
+}
|
|
|
+EXPORT_SYMBOL_GPL(nf_nat_icmp_reply_translation);
|
|
|
+
|
|
|
+/* Protocol registration. */
|
|
|
+int nf_nat_protocol_register(struct nf_nat_protocol *proto)
|
|
|
+{
|
|
|
+ int ret = 0;
|
|
|
+
|
|
|
+ write_lock_bh(&nf_nat_lock);
|
|
|
+ if (nf_nat_protos[proto->protonum] != &nf_nat_unknown_protocol) {
|
|
|
+ ret = -EBUSY;
|
|
|
+ goto out;
|
|
|
+ }
|
|
|
+ nf_nat_protos[proto->protonum] = proto;
|
|
|
+ out:
|
|
|
+ write_unlock_bh(&nf_nat_lock);
|
|
|
+ return ret;
|
|
|
+}
|
|
|
+EXPORT_SYMBOL(nf_nat_protocol_register);
|
|
|
+
|
|
|
+/* Noone stores the protocol anywhere; simply delete it. */
|
|
|
+void nf_nat_protocol_unregister(struct nf_nat_protocol *proto)
|
|
|
+{
|
|
|
+ write_lock_bh(&nf_nat_lock);
|
|
|
+ nf_nat_protos[proto->protonum] = &nf_nat_unknown_protocol;
|
|
|
+ write_unlock_bh(&nf_nat_lock);
|
|
|
+
|
|
|
+ /* Someone could be still looking at the proto in a bh. */
|
|
|
+ synchronize_net();
|
|
|
+}
|
|
|
+EXPORT_SYMBOL(nf_nat_protocol_unregister);
|
|
|
+
|
|
|
+#if defined(CONFIG_IP_NF_CONNTRACK_NETLINK) || \
|
|
|
+ defined(CONFIG_IP_NF_CONNTRACK_NETLINK_MODULE)
|
|
|
+int
|
|
|
+nf_nat_port_range_to_nfattr(struct sk_buff *skb,
|
|
|
+ const struct nf_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;
|
|
|
+}
|
|
|
+EXPORT_SYMBOL_GPL(nf_nat_port_nfattr_to_range);
|
|
|
+
|
|
|
+int
|
|
|
+nf_nat_port_nfattr_to_range(struct nfattr *tb[], struct nf_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(nf_nat_port_range_to_nfattr);
|
|
|
+#endif
|
|
|
+
|
|
|
+static int __init nf_nat_init(void)
|
|
|
+{
|
|
|
+ size_t i;
|
|
|
+
|
|
|
+ /* Leave them the same for the moment. */
|
|
|
+ nf_nat_htable_size = nf_conntrack_htable_size;
|
|
|
+
|
|
|
+ /* One vmalloc for both hash tables */
|
|
|
+ bysource = vmalloc(sizeof(struct list_head) * nf_nat_htable_size);
|
|
|
+ if (!bysource)
|
|
|
+ return -ENOMEM;
|
|
|
+
|
|
|
+ /* Sew in builtin protocols. */
|
|
|
+ write_lock_bh(&nf_nat_lock);
|
|
|
+ for (i = 0; i < MAX_IP_NAT_PROTO; i++)
|
|
|
+ nf_nat_protos[i] = &nf_nat_unknown_protocol;
|
|
|
+ nf_nat_protos[IPPROTO_TCP] = &nf_nat_protocol_tcp;
|
|
|
+ nf_nat_protos[IPPROTO_UDP] = &nf_nat_protocol_udp;
|
|
|
+ nf_nat_protos[IPPROTO_ICMP] = &nf_nat_protocol_icmp;
|
|
|
+ write_unlock_bh(&nf_nat_lock);
|
|
|
+
|
|
|
+ for (i = 0; i < nf_nat_htable_size; i++) {
|
|
|
+ INIT_LIST_HEAD(&bysource[i]);
|
|
|
+ }
|
|
|
+
|
|
|
+ /* FIXME: Man, this is a hack. <SIGH> */
|
|
|
+ NF_CT_ASSERT(nf_conntrack_destroyed == NULL);
|
|
|
+ nf_conntrack_destroyed = &nf_nat_cleanup_conntrack;
|
|
|
+
|
|
|
+ /* Initialize fake conntrack so that NAT will skip it */
|
|
|
+ nf_conntrack_untracked.status |= IPS_NAT_DONE_MASK;
|
|
|
+
|
|
|
+ l3proto = nf_ct_l3proto_find_get((u_int16_t)AF_INET);
|
|
|
+ return 0;
|
|
|
+}
|
|
|
+
|
|
|
+/* Clear NAT section of all conntracks, in case we're loaded again. */
|
|
|
+static int clean_nat(struct nf_conn *i, void *data)
|
|
|
+{
|
|
|
+ struct nf_conn_nat *nat = nfct_nat(i);
|
|
|
+
|
|
|
+ if (!nat)
|
|
|
+ return 0;
|
|
|
+ memset(nat, 0, sizeof(nat));
|
|
|
+ i->status &= ~(IPS_NAT_MASK | IPS_NAT_DONE_MASK | IPS_SEQ_ADJUST);
|
|
|
+ return 0;
|
|
|
+}
|
|
|
+
|
|
|
+static void __exit nf_nat_cleanup(void)
|
|
|
+{
|
|
|
+ nf_ct_iterate_cleanup(&clean_nat, NULL);
|
|
|
+ nf_conntrack_destroyed = NULL;
|
|
|
+ vfree(bysource);
|
|
|
+ nf_ct_l3proto_put(l3proto);
|
|
|
+}
|
|
|
+
|
|
|
+MODULE_LICENSE("GPL");
|
|
|
+
|
|
|
+module_init(nf_nat_init);
|
|
|
+module_exit(nf_nat_cleanup);
|