Remove do_extra_mangle

Index: linux-2.6.10-rc2-bk1-Netfilter/net/ipv4/netfilter/ip_nat_core.c
===================================================================
@@ -179,27 +179,6 @@
 	return 0;
 }
 
-#ifdef CONFIG_IP_NF_NAT_LOCAL
-/* If it's really a local destination manip, it may need to do a
-   source manip too. */
-static void
-do_extra_mangle(u_int32_t var_ip, u_int32_t *other_ipp)
-{
-	struct flowi fl = { .nl_u = { .ip4_u = { .daddr = var_ip } } };
-	struct rtable *rt;
-
-	/* FIXME: IPTOS_TOS(iph->tos) --RR */
-	if (ip_route_output_key(&rt, &fl) != 0) {
-		DEBUGP("do_extra_mangle: Can't get route to %u.%u.%u.%u\n",
-		       NIPQUAD(var_ip));
-		return;
-	}
-
-	*other_ipp = rt->rt_src;
-	ip_rt_put(rt);
-}
-#endif
-
 /* Simple way to iterate through all. */
 static inline int fake_cmp(const struct ip_conntrack *ct,
 			   u_int32_t src, u_int32_t dst, u_int16_t protonum,

@@ -246,30 +225,32 @@
 {
 	unsigned int best_score = 0xFFFFFFFF;
 	struct ip_conntrack_tuple best_tuple = *tuple;
-	u_int32_t *var_ipp, *other_ipp, saved_ip, orig_dstip;
+	u_int32_t *var_ipp;
 	static unsigned int randomness;
 	/* Host order */
 	u_int32_t minip, maxip, j;
 
-	if (HOOK2MANIP(hooknum) == IP_NAT_MANIP_SRC) {
+	/* No IP mapping?  Do nothing. */
+	if (!(range->flags & IP_NAT_RANGE_MAP_IPS))
+		return;
+
+	if (HOOK2MANIP(hooknum) == IP_NAT_MANIP_SRC)
 		var_ipp = &tuple->src.ip;
-		saved_ip = tuple->dst.ip;
-		other_ipp = &tuple->dst.ip;
-	} else {
+	else
 		var_ipp = &tuple->dst.ip;
-		saved_ip = tuple->src.ip;
-		other_ipp = &tuple->src.ip;
+
+	/* Fast path: only one choice. */
+	if (range->min_ip == range->max_ip) {
+		*var_ipp = range->min_ip;
+		return;
 	}
-	/* Don't do do_extra_mangle unless necessary (overrides
-           explicit socket bindings, for example) */
-	orig_dstip = tuple->dst.ip;
-
-	if (range->flags & IP_NAT_RANGE_MAP_IPS) {
-		minip = ntohl(range->min_ip);
-		maxip = ntohl(range->max_ip);
-	} else
-		minip = maxip = ntohl(*var_ipp);
 
+	minip = ntohl(range->min_ip);
+	maxip = ntohl(range->max_ip);
+
+	/* FIXME: use hash of ips like ipt_SAME, not randomness.
+	   This way same pairs get same IP: think Internet Banking.
+	 */
 	randomness++;
 	for (j = 0; j < maxip - minip + 1; j++) {
 		unsigned int score;

@@ -277,16 +258,6 @@
 		*var_ipp = htonl(minip + (randomness + j) 
 				 % (maxip - minip + 1));
 
-		/* Reset the other ip in case it was mangled by
-		 * do_extra_mangle last time. */
-		*other_ipp = saved_ip;
-
-#ifdef CONFIG_IP_NF_NAT_LOCAL
-		if (hooknum == NF_IP_LOCAL_OUT
-		    && *var_ipp != orig_dstip)
-			do_extra_mangle(*var_ipp, other_ipp);
-#endif
-
 		/* Count how many others map onto this. */
 		score = count_maps(tuple->src.ip, tuple->dst.ip,
 				   tuple->dst.protonum, conntrack);

@@ -303,38 +274,6 @@
 	*tuple = best_tuple;
 }
 
-/* Fast version doesn't iterate through hash chains, but only handles
-   common case of single IP address (null NAT, masquerade) */
-static void
-find_best_ips_proto_fast(struct ip_conntrack_tuple *tuple,
-			 const struct ip_nat_range *range,
-			 const struct ip_conntrack *conntrack,
-			 unsigned int hooknum)
-{
-	/* Leave IP address alone if we're not to map IP addresses. */
-	if (!(range->flags & IP_NAT_RANGE_MAP_IPS))
-		return;
-
-	if (range->min_ip != range->max_ip) {
-		find_best_ips_proto(tuple, range, conntrack, hooknum);
-		return;
-	}
-
-	if (HOOK2MANIP(hooknum) == IP_NAT_MANIP_SRC)
-		tuple->src.ip = range->min_ip;
-	else {
-		/* Only do extra mangle when required (breaks socket
-		   binding) */
-#ifdef CONFIG_IP_NF_NAT_LOCAL
-		if (tuple->dst.ip != range->min_ip
-		    && hooknum == NF_IP_LOCAL_OUT)
-			do_extra_mangle(range->min_ip, &tuple->src.ip);
-		else
-#endif
-		tuple->dst.ip = range->min_ip;
-	}
-}
-
 /* 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

@@ -369,7 +308,7 @@
 	/* 2) Select the least-used IP/proto combination in the given
 	   range. */
 	*tuple = *orig_tuple;
-	find_best_ips_proto_fast(tuple, range, conntrack, hooknum);
+	find_best_ips_proto(tuple, range, conntrack, hooknum);
 
 	/* 3) The per-protocol part of the manip is made to map into
 	   the range to make a unique tuple. */

@@ -470,6 +409,9 @@
 
 	/* Has source changed?. */
 	if (!ip_ct_tuple_src_equal(&new_tuple, &orig_tp)) {
+		IP_NF_ASSERT(HOOK2MANIP(hooknum) == IP_NAT_MANIP_SRC);
+		IP_NF_ASSERT(ip_ct_tuple_dst_equal(&new_tuple, &orig_tp));
+
 		/* In this direction, a source manip. */
 		info->manips[info->num_manips++] =
 			((struct ip_nat_info_manip)

@@ -488,6 +430,8 @@
 
 	/* Has destination changed? */
 	if (!ip_ct_tuple_dst_equal(&new_tuple, &orig_tp)) {
+		IP_NF_ASSERT(HOOK2MANIP(hooknum) == IP_NAT_MANIP_DST);
+
 		/* In this direction, a destination manip */
 		info->manips[info->num_manips++] =
 			((struct ip_nat_info_manip)