Compatibility code is modified not to rely on kernel version numbers

Instead the kernel source code is checked to verify the different
compatibility issues for the supported kernel releases.

This way hopefully backported features will be handled properly.

3 files changed, 42 insertions, 6 deletions

diff --git a/kernel/net/netfilter/ipset/ip_set_core.c b/kernel/net/netfilter/ipset/ip_set_core.c
index 9506973..c1989d9 100644
--- a/kernel/net/netfilter/ipset/ip_set_core.c
+++ b/kernel/net/netfilter/ipset/ip_set_core.c
@@ -1388,11 +1388,11 @@ ip_set_dump(struct sock *ctnl, struct sk_buff *skb,
 	if (unlikely(protocol_failed(attr)))
 		return -IPSET_ERR_PROTOCOL;
 
-#if LINUX_VERSION_CODE < KERNEL_VERSION(3, 1, 0)
+#if HAVE_NETLINK_DUMP_START_ARGS == 5
 	return netlink_dump_start(ctnl, skb, nlh,
 				  ip_set_dump_start,
 				  ip_set_dump_done);
-#elif LINUX_VERSION_CODE < KERNEL_VERSION(3, 4, 0)
+#elif HAVE_NETLINK_DUMP_START_ARGS == 6
 	return netlink_dump_start(ctnl, skb, nlh,
 				  ip_set_dump_start,
 				  ip_set_dump_done, 0);
@@ -1977,20 +1977,42 @@ static struct nf_sockopt_ops so_set __read_mostly = {
 static int __net_init
 ip_set_net_init(struct net *net)
 {
-	struct ip_set_net *inst = ip_set_pernet(net);
+	struct ip_set_net *inst;
 	struct ip_set **list;
 
+#ifdef HAVE_NET_OPS_ID
+	inst = ip_set_pernet(net);
+#else
+	int err;
+
+	inst = kzalloc(sizeof(struct ip_set_net), GFP_KERNEL);
+	if (!inst)
+		return -ENOMEM;
+	err = net_assign_generic(net, ip_set_net_id, inst);
+	if (err < 0)
+		goto err_alloc;
+#endif
 	inst->ip_set_max = max_sets ? max_sets : CONFIG_IP_SET_MAX;
 	if (inst->ip_set_max >= IPSET_INVALID_ID)
 		inst->ip_set_max = IPSET_INVALID_ID - 1;
 
 	list = kzalloc(sizeof(struct ip_set *) * inst->ip_set_max, GFP_KERNEL);
 	if (!list)
+#ifdef HAVE_NET_OPS_ID
 		return -ENOMEM;
+#else
+		goto err_alloc;
+#endif
 	inst->is_deleted = 0;
 	rcu_assign_pointer(inst->ip_set_list, list);
 	pr_notice("ip_set: protocol %u\n", IPSET_PROTOCOL);
 	return 0;
+
+#ifndef HAVE_NET_OPS_ID
+err_alloc:
+	kfree(inst);
+	return err;
+#endif
 }
 
 static void __net_exit
@@ -2009,13 +2031,18 @@ ip_set_net_exit(struct net *net)
 			ip_set_destroy_set(inst, i);
 	}
 	kfree(rcu_dereference_protected(inst->ip_set_list, 1));
+#ifndef HAVE_NET_OPS_ID
+	kfree(inst);
+#endif
 }
 
 static struct pernet_operations ip_set_net_ops = {
 	.init	= ip_set_net_init,
 	.exit   = ip_set_net_exit,
+#ifdef HAVE_NET_OPS_ID
 	.id	= &ip_set_net_id,
 	.size	= sizeof(struct ip_set_net)
+#endif
 };
 
 
@@ -2033,7 +2060,11 @@ ip_set_init(void)
 		nfnetlink_subsys_unregister(&ip_set_netlink_subsys);
 		return ret;
 	}
+#ifdef HAVE_NET_OPS_ID
 	ret = register_pernet_subsys(&ip_set_net_ops);
+#else
+	ret = register_pernet_gen_device(&ip_set_net_id, &ip_set_net_ops);
+#endif
 	if (ret) {
 		pr_err("ip_set: cannot register pernet_subsys.\n");
 		nf_unregister_sockopt(&so_set);
@@ -2046,7 +2077,11 @@ ip_set_init(void)
 static void __exit
 ip_set_fini(void)
 {
+#ifdef HAVE_NET_OPS_ID
 	unregister_pernet_subsys(&ip_set_net_ops);
+#else
+	unregister_pernet_gen_device(ip_set_net_id, &ip_set_net_ops);
+#endif
 	nf_unregister_sockopt(&so_set);
 	nfnetlink_subsys_unregister(&ip_set_netlink_subsys);
 	pr_debug("these are the famous last words\n");
diff --git a/kernel/net/netfilter/ipset/ip_set_getport.c b/kernel/net/netfilter/ipset/ip_set_getport.c
index a0d96eb..5d5ff82 100644
--- a/kernel/net/netfilter/ipset/ip_set_getport.c
+++ b/kernel/net/netfilter/ipset/ip_set_getport.c
@@ -8,7 +8,7 @@
 /* Get Layer-4 data from the packets */
 
 #include <linux/version.h>
-#if LINUX_VERSION_CODE >= KERNEL_VERSION(3, 2, 0)
+#ifdef HAVE_EXPORT_H
 #include <linux/export.h>
 #endif
 #include <linux/ip.h>
@@ -21,6 +21,7 @@
 #include <net/ipv6.h>
 
 #include <linux/netfilter/ipset/ip_set_getport.h>
+#include <linux/netfilter/ipset/ip_set_compat.h>
 
 /* We must handle non-linear skbs */
 static bool
@@ -138,7 +139,7 @@ ip_set_get_ip6_port(const struct sk_buff *skb, bool src,
 	__be16 frag_off = 0;
 
 	nexthdr = ipv6_hdr(skb)->nexthdr;
-#if LINUX_VERSION_CODE >= KERNEL_VERSION(3, 3, 0)
+#if HAVE_IPV6_SKIP_EXTHDR_ARGS == 4
 	protoff = ipv6_skip_exthdr(skb, sizeof(struct ipv6hdr), &nexthdr,
 				   &frag_off);
 #else
diff --git a/kernel/net/netfilter/ipset/pfxlen.c b/kernel/net/netfilter/ipset/pfxlen.c
index 1fe890f..e69f5ef 100644
--- a/kernel/net/netfilter/ipset/pfxlen.c
+++ b/kernel/net/netfilter/ipset/pfxlen.c
@@ -1,5 +1,5 @@
 #include <linux/version.h>
-#if LINUX_VERSION_CODE >= KERNEL_VERSION(3, 2, 0)
+#ifdef HAVE_EXPORT_H
 #include <linux/export.h>
 #endif
 #include <linux/netfilter/ipset/pfxlen.h>