1 files changed, 405 insertions, 0 deletions
diff --git a/net/netfilter/nf_conntrack_proto_udplite.c b/net/netfilter/nf_conntrack_proto_udplite.c
new file mode 100644
index 000000000..c5903d164
--- /dev/null
+++ b/net/netfilter/nf_conntrack_proto_udplite.c
@@ -0,0 +1,405 @@
+/* (C) 1999-2001 Paul `Rusty' Russell
+ * (C) 2002-2004 Netfilter Core Team <coreteam@netfilter.org>
+ * (C) 2007 Patrick McHardy <kaber@trash.net>
+ *
+ * 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/types.h>
+#include <linux/timer.h>
+#include <linux/module.h>
+#include <linux/udp.h>
+#include <linux/seq_file.h>
+#include <linux/skbuff.h>
+#include <linux/ipv6.h>
+#include <net/ip6_checksum.h>
+#include <net/checksum.h>
+
+#include <linux/netfilter.h>
+#include <linux/netfilter_ipv4.h>
+#include <linux/netfilter_ipv6.h>
+#include <net/netfilter/nf_conntrack_l4proto.h>
+#include <net/netfilter/nf_conntrack_ecache.h>
+#include <net/netfilter/nf_log.h>
+
+enum udplite_conntrack {
+	UDPLITE_CT_UNREPLIED,
+	UDPLITE_CT_REPLIED,
+	UDPLITE_CT_MAX
+};
+
+static unsigned int udplite_timeouts[UDPLITE_CT_MAX] = {
+	[UDPLITE_CT_UNREPLIED]	= 30*HZ,
+	[UDPLITE_CT_REPLIED]	= 180*HZ,
+};
+
+static int udplite_net_id __read_mostly;
+struct udplite_net {
+	struct nf_proto_net pn;
+	unsigned int timeouts[UDPLITE_CT_MAX];
+};
+
+static inline struct udplite_net *udplite_pernet(struct net *net)
+{
+	return net_generic(net, udplite_net_id);
+}
+
+static bool udplite_pkt_to_tuple(const struct sk_buff *skb,
+				 unsigned int dataoff,
+				 struct nf_conntrack_tuple *tuple)
+{
+	const struct udphdr *hp;
+	struct udphdr _hdr;
+
+	hp = skb_header_pointer(skb, dataoff, sizeof(_hdr), &_hdr);
+	if (hp == NULL)
+		return false;
+
+	tuple->src.u.udp.port = hp->source;
+	tuple->dst.u.udp.port = hp->dest;
+	return true;
+}
+
+static bool udplite_invert_tuple(struct nf_conntrack_tuple *tuple,
+				 const struct nf_conntrack_tuple *orig)
+{
+	tuple->src.u.udp.port = orig->dst.u.udp.port;
+	tuple->dst.u.udp.port = orig->src.u.udp.port;
+	return true;
+}
+
+/* Print out the per-protocol part of the tuple. */
+static void udplite_print_tuple(struct seq_file *s,
+				const struct nf_conntrack_tuple *tuple)
+{
+	seq_printf(s, "sport=%hu dport=%hu ",
+		   ntohs(tuple->src.u.udp.port),
+		   ntohs(tuple->dst.u.udp.port));
+}
+
+static unsigned int *udplite_get_timeouts(struct net *net)
+{
+	return udplite_pernet(net)->timeouts;
+}
+
+/* Returns verdict for packet, and may modify conntracktype */
+static int udplite_packet(struct nf_conn *ct,
+			  const struct sk_buff *skb,
+			  unsigned int dataoff,
+			  enum ip_conntrack_info ctinfo,
+			  u_int8_t pf,
+			  unsigned int hooknum,
+			  unsigned int *timeouts)
+{
+	/* If we've seen traffic both ways, this is some kind of UDP
+	   stream.  Extend timeout. */
+	if (test_bit(IPS_SEEN_REPLY_BIT, &ct->status)) {
+		nf_ct_refresh_acct(ct, ctinfo, skb,
+				   timeouts[UDPLITE_CT_REPLIED]);
+		/* Also, more likely to be important, and not a probe */
+		if (!test_and_set_bit(IPS_ASSURED_BIT, &ct->status))
+			nf_conntrack_event_cache(IPCT_ASSURED, ct);
+	} else {
+		nf_ct_refresh_acct(ct, ctinfo, skb,
+				   timeouts[UDPLITE_CT_UNREPLIED]);
+	}
+	return NF_ACCEPT;
+}
+
+/* Called when a new connection for this protocol found. */
+static bool udplite_new(struct nf_conn *ct, const struct sk_buff *skb,
+			unsigned int dataoff, unsigned int *timeouts)
+{
+	return true;
+}
+
+static int udplite_error(struct net *net, struct nf_conn *tmpl,
+			 struct sk_buff *skb,
+			 unsigned int dataoff,
+			 enum ip_conntrack_info *ctinfo,
+			 u_int8_t pf,
+			 unsigned int hooknum)
+{
+	unsigned int udplen = skb->len - dataoff;
+	const struct udphdr *hdr;
+	struct udphdr _hdr;
+	unsigned int cscov;
+
+	/* Header is too small? */
+	hdr = skb_header_pointer(skb, dataoff, sizeof(_hdr), &_hdr);
+	if (hdr == NULL) {
+		if (LOG_INVALID(net, IPPROTO_UDPLITE))
+			nf_log_packet(net, pf, 0, skb, NULL, NULL, NULL,
+				      "nf_ct_udplite: short packet ");
+		return -NF_ACCEPT;
+	}
+
+	cscov = ntohs(hdr->len);
+	if (cscov == 0)
+		cscov = udplen;
+	else if (cscov < sizeof(*hdr) || cscov > udplen) {
+		if (LOG_INVALID(net, IPPROTO_UDPLITE))
+			nf_log_packet(net, pf, 0, skb, NULL, NULL, NULL,
+				"nf_ct_udplite: invalid checksum coverage ");
+		return -NF_ACCEPT;
+	}
+
+	/* UDPLITE mandates checksums */
+	if (!hdr->check) {
+		if (LOG_INVALID(net, IPPROTO_UDPLITE))
+			nf_log_packet(net, pf, 0, skb, NULL, NULL, NULL,
+				      "nf_ct_udplite: checksum missing ");
+		return -NF_ACCEPT;
+	}
+
+	/* Checksum invalid? Ignore. */
+	if (net->ct.sysctl_checksum && hooknum == NF_INET_PRE_ROUTING &&
+	    nf_checksum_partial(skb, hooknum, dataoff, cscov, IPPROTO_UDP,
+	    			pf)) {
+		if (LOG_INVALID(net, IPPROTO_UDPLITE))
+			nf_log_packet(net, pf, 0, skb, NULL, NULL, NULL,
+				      "nf_ct_udplite: bad UDPLite checksum ");
+		return -NF_ACCEPT;
+	}
+
+	return NF_ACCEPT;
+}
+
+#if IS_ENABLED(CONFIG_NF_CT_NETLINK_TIMEOUT)
+
+#include <linux/netfilter/nfnetlink.h>
+#include <linux/netfilter/nfnetlink_cttimeout.h>
+
+static int udplite_timeout_nlattr_to_obj(struct nlattr *tb[],
+					 struct net *net, void *data)
+{
+	unsigned int *timeouts = data;
+	struct udplite_net *un = udplite_pernet(net);
+
+	/* set default timeouts for UDPlite. */
+	timeouts[UDPLITE_CT_UNREPLIED] = un->timeouts[UDPLITE_CT_UNREPLIED];
+	timeouts[UDPLITE_CT_REPLIED] = un->timeouts[UDPLITE_CT_REPLIED];
+
+	if (tb[CTA_TIMEOUT_UDPLITE_UNREPLIED]) {
+		timeouts[UDPLITE_CT_UNREPLIED] =
+		  ntohl(nla_get_be32(tb[CTA_TIMEOUT_UDPLITE_UNREPLIED])) * HZ;
+	}
+	if (tb[CTA_TIMEOUT_UDPLITE_REPLIED]) {
+		timeouts[UDPLITE_CT_REPLIED] =
+		  ntohl(nla_get_be32(tb[CTA_TIMEOUT_UDPLITE_REPLIED])) * HZ;
+	}
+	return 0;
+}
+
+static int
+udplite_timeout_obj_to_nlattr(struct sk_buff *skb, const void *data)
+{
+	const unsigned int *timeouts = data;
+
+	if (nla_put_be32(skb, CTA_TIMEOUT_UDPLITE_UNREPLIED,
+			 htonl(timeouts[UDPLITE_CT_UNREPLIED] / HZ)) ||
+	    nla_put_be32(skb, CTA_TIMEOUT_UDPLITE_REPLIED,
+			 htonl(timeouts[UDPLITE_CT_REPLIED] / HZ)))
+		goto nla_put_failure;
+	return 0;
+
+nla_put_failure:
+	return -ENOSPC;
+}
+
+static const struct nla_policy
+udplite_timeout_nla_policy[CTA_TIMEOUT_UDPLITE_MAX+1] = {
+	[CTA_TIMEOUT_UDPLITE_UNREPLIED]	= { .type = NLA_U32 },
+	[CTA_TIMEOUT_UDPLITE_REPLIED]	= { .type = NLA_U32 },
+};
+#endif /* CONFIG_NF_CT_NETLINK_TIMEOUT */
+
+#ifdef CONFIG_SYSCTL
+static struct ctl_table udplite_sysctl_table[] = {
+	{
+		.procname	= "nf_conntrack_udplite_timeout",
+		.maxlen		= sizeof(unsigned int),
+		.mode		= 0644,
+		.proc_handler	= proc_dointvec_jiffies,
+	},
+	{
+		.procname	= "nf_conntrack_udplite_timeout_stream",
+		.maxlen		= sizeof(unsigned int),
+		.mode		= 0644,
+		.proc_handler	= proc_dointvec_jiffies,
+	},
+	{ }
+};
+#endif /* CONFIG_SYSCTL */
+
+static int udplite_kmemdup_sysctl_table(struct nf_proto_net *pn,
+					struct udplite_net *un)
+{
+#ifdef CONFIG_SYSCTL
+	if (pn->ctl_table)
+		return 0;
+
+	pn->ctl_table = kmemdup(udplite_sysctl_table,
+				sizeof(udplite_sysctl_table),
+				GFP_KERNEL);
+	if (!pn->ctl_table)
+		return -ENOMEM;
+
+	pn->ctl_table[0].data = &un->timeouts[UDPLITE_CT_UNREPLIED];
+	pn->ctl_table[1].data = &un->timeouts[UDPLITE_CT_REPLIED];
+#endif
+	return 0;
+}
+
+static int udplite_init_net(struct net *net, u_int16_t proto)
+{
+	struct udplite_net *un = udplite_pernet(net);
+	struct nf_proto_net *pn = &un->pn;
+
+	if (!pn->users) {
+		int i;
+
+		for (i = 0 ; i < UDPLITE_CT_MAX; i++)
+			un->timeouts[i] = udplite_timeouts[i];
+	}
+
+	return udplite_kmemdup_sysctl_table(pn, un);
+}
+
+static struct nf_conntrack_l4proto nf_conntrack_l4proto_udplite4 __read_mostly =
+{
+	.l3proto		= PF_INET,
+	.l4proto		= IPPROTO_UDPLITE,
+	.name			= "udplite",
+	.pkt_to_tuple		= udplite_pkt_to_tuple,
+	.invert_tuple		= udplite_invert_tuple,
+	.print_tuple		= udplite_print_tuple,
+	.packet			= udplite_packet,
+	.get_timeouts		= udplite_get_timeouts,
+	.new			= udplite_new,
+	.error			= udplite_error,
+#if IS_ENABLED(CONFIG_NF_CT_NETLINK)
+	.tuple_to_nlattr	= nf_ct_port_tuple_to_nlattr,
+	.nlattr_tuple_size	= nf_ct_port_nlattr_tuple_size,
+	.nlattr_to_tuple	= nf_ct_port_nlattr_to_tuple,
+	.nla_policy		= nf_ct_port_nla_policy,
+#endif
+#if IS_ENABLED(CONFIG_NF_CT_NETLINK_TIMEOUT)
+	.ctnl_timeout		= {
+		.nlattr_to_obj	= udplite_timeout_nlattr_to_obj,
+		.obj_to_nlattr	= udplite_timeout_obj_to_nlattr,
+		.nlattr_max	= CTA_TIMEOUT_UDPLITE_MAX,
+		.obj_size	= sizeof(unsigned int) *
+					CTA_TIMEOUT_UDPLITE_MAX,
+		.nla_policy	= udplite_timeout_nla_policy,
+	},
+#endif /* CONFIG_NF_CT_NETLINK_TIMEOUT */
+	.net_id			= &udplite_net_id,
+	.init_net		= udplite_init_net,
+};
+
+static struct nf_conntrack_l4proto nf_conntrack_l4proto_udplite6 __read_mostly =
+{
+	.l3proto		= PF_INET6,
+	.l4proto		= IPPROTO_UDPLITE,
+	.name			= "udplite",
+	.pkt_to_tuple		= udplite_pkt_to_tuple,
+	.invert_tuple		= udplite_invert_tuple,
+	.print_tuple		= udplite_print_tuple,
+	.packet			= udplite_packet,
+	.get_timeouts		= udplite_get_timeouts,
+	.new			= udplite_new,
+	.error			= udplite_error,
+#if IS_ENABLED(CONFIG_NF_CT_NETLINK)
+	.tuple_to_nlattr	= nf_ct_port_tuple_to_nlattr,
+	.nlattr_tuple_size	= nf_ct_port_nlattr_tuple_size,
+	.nlattr_to_tuple	= nf_ct_port_nlattr_to_tuple,
+	.nla_policy		= nf_ct_port_nla_policy,
+#endif
+#if IS_ENABLED(CONFIG_NF_CT_NETLINK_TIMEOUT)
+	.ctnl_timeout		= {
+		.nlattr_to_obj	= udplite_timeout_nlattr_to_obj,
+		.obj_to_nlattr	= udplite_timeout_obj_to_nlattr,
+		.nlattr_max	= CTA_TIMEOUT_UDPLITE_MAX,
+		.obj_size	= sizeof(unsigned int) *
+					CTA_TIMEOUT_UDPLITE_MAX,
+		.nla_policy	= udplite_timeout_nla_policy,
+	},
+#endif /* CONFIG_NF_CT_NETLINK_TIMEOUT */
+	.net_id			= &udplite_net_id,
+	.init_net		= udplite_init_net,
+};
+
+static int udplite_net_init(struct net *net)
+{
+	int ret = 0;
+
+	ret = nf_ct_l4proto_pernet_register(net, &nf_conntrack_l4proto_udplite4);
+	if (ret < 0) {
+		pr_err("nf_conntrack_udplite4: pernet registration failed.\n");
+		goto out;
+	}
+	ret = nf_ct_l4proto_pernet_register(net, &nf_conntrack_l4proto_udplite6);
+	if (ret < 0) {
+		pr_err("nf_conntrack_udplite6: pernet registration failed.\n");
+		goto cleanup_udplite4;
+	}
+	return 0;
+
+cleanup_udplite4:
+	nf_ct_l4proto_pernet_unregister(net, &nf_conntrack_l4proto_udplite4);
+out:
+	return ret;
+}
+
+static void udplite_net_exit(struct net *net)
+{
+	nf_ct_l4proto_pernet_unregister(net, &nf_conntrack_l4proto_udplite6);
+	nf_ct_l4proto_pernet_unregister(net, &nf_conntrack_l4proto_udplite4);
+}
+
+static struct pernet_operations udplite_net_ops = {
+	.init = udplite_net_init,
+	.exit = udplite_net_exit,
+	.id   = &udplite_net_id,
+	.size = sizeof(struct udplite_net),
+};
+
+static int __init nf_conntrack_proto_udplite_init(void)
+{
+	int ret;
+
+	ret = register_pernet_subsys(&udplite_net_ops);
+	if (ret < 0)
+		goto out_pernet;
+
+	ret = nf_ct_l4proto_register(&nf_conntrack_l4proto_udplite4);
+	if (ret < 0)
+		goto out_udplite4;
+
+	ret = nf_ct_l4proto_register(&nf_conntrack_l4proto_udplite6);
+	if (ret < 0)
+		goto out_udplite6;
+
+	return 0;
+out_udplite6:
+	nf_ct_l4proto_unregister(&nf_conntrack_l4proto_udplite4);
+out_udplite4:
+	unregister_pernet_subsys(&udplite_net_ops);
+out_pernet:
+	return ret;
+}
+
+static void __exit nf_conntrack_proto_udplite_exit(void)
+{
+	nf_ct_l4proto_unregister(&nf_conntrack_l4proto_udplite6);
+	nf_ct_l4proto_unregister(&nf_conntrack_l4proto_udplite4);
+	unregister_pernet_subsys(&udplite_net_ops);
+}
+
+module_init(nf_conntrack_proto_udplite_init);
+module_exit(nf_conntrack_proto_udplite_exit);
+
+MODULE_LICENSE("GPL");