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authorPatrick McHardy <kaber@trash.net>2007-07-14 20:48:44 -0700
committerDavid S. Miller <davem@davemloft.net>2007-07-14 20:48:44 -0700
commit59eecdfb166f6846ae356ddc744abed5820ad965 (patch)
tree5cfbafad5bcb8d5197b9f515f1e23387427cea29 /net
parent61075af51f252913401c41fbe94075b46c94e9f1 (diff)
[NETFILTER]: nf_conntrack: UDPLITE support
Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net')
-rw-r--r--net/netfilter/Kconfig10
-rw-r--r--net/netfilter/Makefile1
-rw-r--r--net/netfilter/nf_conntrack_proto_udplite.c266
3 files changed, 277 insertions, 0 deletions
diff --git a/net/netfilter/Kconfig b/net/netfilter/Kconfig
index 9415b9a5dba..3ac39f1ec77 100644
--- a/net/netfilter/Kconfig
+++ b/net/netfilter/Kconfig
@@ -102,6 +102,16 @@ config NF_CT_PROTO_SCTP
If you want to compile it as a module, say M here and read
<file:Documentation/kbuild/modules.txt>. If unsure, say `N'.
+config NF_CT_PROTO_UDPLITE
+ tristate 'UDP-Lite protocol connection tracking support (EXPERIMENTAL)'
+ depends on EXPERIMENTAL && NF_CONNTRACK
+ help
+ With this option enabled, the layer 3 independent connection
+ tracking code will be able to do state tracking on UDP-Lite
+ connections.
+
+ To compile it as a module, choose M here. If unsure, say N.
+
config NF_CONNTRACK_AMANDA
tristate "Amanda backup protocol support"
depends on NF_CONNTRACK
diff --git a/net/netfilter/Makefile b/net/netfilter/Makefile
index 3e4a16aeb04..0c054bf2797 100644
--- a/net/netfilter/Makefile
+++ b/net/netfilter/Makefile
@@ -16,6 +16,7 @@ obj-$(CONFIG_NF_CONNTRACK) += nf_conntrack.o
# SCTP protocol connection tracking
obj-$(CONFIG_NF_CT_PROTO_GRE) += nf_conntrack_proto_gre.o
obj-$(CONFIG_NF_CT_PROTO_SCTP) += nf_conntrack_proto_sctp.o
+obj-$(CONFIG_NF_CT_PROTO_UDPLITE) += nf_conntrack_proto_udplite.o
# netlink interface for nf_conntrack
obj-$(CONFIG_NF_CT_NETLINK) += nf_conntrack_netlink.o
diff --git a/net/netfilter/nf_conntrack_proto_udplite.c b/net/netfilter/nf_conntrack_proto_udplite.c
new file mode 100644
index 00000000000..93e747b5396
--- /dev/null
+++ b/net/netfilter/nf_conntrack_proto_udplite.c
@@ -0,0 +1,266 @@
+/* (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/netfilter.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>
+
+static unsigned int nf_ct_udplite_timeout __read_mostly = 30*HZ;
+static unsigned int nf_ct_udplite_timeout_stream __read_mostly = 180*HZ;
+
+static int udplite_pkt_to_tuple(const struct sk_buff *skb,
+ unsigned int dataoff,
+ struct nf_conntrack_tuple *tuple)
+{
+ struct udphdr _hdr, *hp;
+
+ hp = skb_header_pointer(skb, dataoff, sizeof(_hdr), &_hdr);
+ if (hp == NULL)
+ return 0;
+
+ tuple->src.u.udp.port = hp->source;
+ tuple->dst.u.udp.port = hp->dest;
+ return 1;
+}
+
+static int 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 1;
+}
+
+/* Print out the per-protocol part of the tuple. */
+static int udplite_print_tuple(struct seq_file *s,
+ const struct nf_conntrack_tuple *tuple)
+{
+ return seq_printf(s, "sport=%hu dport=%hu ",
+ ntohs(tuple->src.u.udp.port),
+ ntohs(tuple->dst.u.udp.port));
+}
+
+/* Print out the private part of the conntrack. */
+static int udplite_print_conntrack(struct seq_file *s,
+ const struct nf_conn *conntrack)
+{
+ return 0;
+}
+
+/* Returns verdict for packet, and may modify conntracktype */
+static int udplite_packet(struct nf_conn *conntrack,
+ const struct sk_buff *skb,
+ unsigned int dataoff,
+ enum ip_conntrack_info ctinfo,
+ int pf,
+ unsigned int hooknum)
+{
+ /* If we've seen traffic both ways, this is some kind of UDP
+ stream. Extend timeout. */
+ if (test_bit(IPS_SEEN_REPLY_BIT, &conntrack->status)) {
+ nf_ct_refresh_acct(conntrack, ctinfo, skb,
+ nf_ct_udplite_timeout_stream);
+ /* Also, more likely to be important, and not a probe */
+ if (!test_and_set_bit(IPS_ASSURED_BIT, &conntrack->status))
+ nf_conntrack_event_cache(IPCT_STATUS, skb);
+ } else
+ nf_ct_refresh_acct(conntrack, ctinfo, skb,
+ nf_ct_udplite_timeout);
+
+ return NF_ACCEPT;
+}
+
+/* Called when a new connection for this protocol found. */
+static int udplite_new(struct nf_conn *conntrack, const struct sk_buff *skb,
+ unsigned int dataoff)
+{
+ return 1;
+}
+
+static int udplite_error(struct sk_buff *skb, unsigned int dataoff,
+ enum ip_conntrack_info *ctinfo,
+ int pf,
+ unsigned int hooknum)
+{
+ unsigned int udplen = skb->len - dataoff;
+ struct udphdr _hdr, *hdr;
+ unsigned int cscov;
+
+ /* Header is too small? */
+ hdr = skb_header_pointer(skb, dataoff, sizeof(_hdr), &_hdr);
+ if (hdr == NULL) {
+ if (LOG_INVALID(IPPROTO_UDPLITE))
+ nf_log_packet(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(IPPROTO_UDPLITE))
+ nf_log_packet(pf, 0, skb, NULL, NULL, NULL,
+ "nf_ct_udplite: invalid checksum coverage ");
+ return -NF_ACCEPT;
+ }
+
+ /* UDPLITE mandates checksums */
+ if (!hdr->check) {
+ if (LOG_INVALID(IPPROTO_UDPLITE))
+ nf_log_packet(pf, 0, skb, NULL, NULL, NULL,
+ "nf_ct_udplite: checksum missing ");
+ return -NF_ACCEPT;
+ }
+
+ /* Checksum invalid? Ignore. */
+ if (nf_conntrack_checksum && !skb_csum_unnecessary(skb) &&
+ ((pf == PF_INET && hooknum == NF_IP_PRE_ROUTING) ||
+ (pf == PF_INET6 && hooknum == NF_IP6_PRE_ROUTING))) {
+ if (pf == PF_INET) {
+ struct iphdr *iph = ip_hdr(skb);
+
+ skb->csum = csum_tcpudp_nofold(iph->saddr, iph->daddr,
+ udplen, IPPROTO_UDPLITE, 0);
+ } else {
+ struct ipv6hdr *ipv6h = ipv6_hdr(skb);
+ __wsum hsum = skb_checksum(skb, 0, dataoff, 0);
+
+ skb->csum = ~csum_unfold(
+ csum_ipv6_magic(&ipv6h->saddr, &ipv6h->daddr,
+ udplen, IPPROTO_UDPLITE,
+ csum_sub(0, hsum)));
+ }
+
+ skb->ip_summed = CHECKSUM_NONE;
+ if (__skb_checksum_complete_head(skb, dataoff + cscov)) {
+ if (LOG_INVALID(IPPROTO_UDPLITE))
+ nf_log_packet(pf, 0, skb, NULL, NULL, NULL,
+ "nf_ct_udplite: bad UDPLite "
+ "checksum ");
+ return -NF_ACCEPT;
+ }
+ skb->ip_summed = CHECKSUM_UNNECESSARY;
+ }
+
+ return NF_ACCEPT;
+}
+
+#ifdef CONFIG_SYSCTL
+static unsigned int udplite_sysctl_table_users;
+static struct ctl_table_header *udplite_sysctl_header;
+static struct ctl_table udplite_sysctl_table[] = {
+ {
+ .ctl_name = CTL_UNNUMBERED,
+ .procname = "nf_conntrack_udplite_timeout",
+ .data = &nf_ct_udplite_timeout,
+ .maxlen = sizeof(unsigned int),
+ .mode = 0644,
+ .proc_handler = &proc_dointvec_jiffies,
+ },
+ {
+ .ctl_name = CTL_UNNUMBERED,
+ .procname = "nf_conntrack_udplite_timeout_stream",
+ .data = &nf_ct_udplite_timeout_stream,
+ .maxlen = sizeof(unsigned int),
+ .mode = 0644,
+ .proc_handler = &proc_dointvec_jiffies,
+ },
+ {
+ .ctl_name = 0
+ }
+};
+#endif /* CONFIG_SYSCTL */
+
+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,
+ .print_conntrack = udplite_print_conntrack,
+ .packet = udplite_packet,
+ .new = udplite_new,
+ .error = udplite_error,
+#if defined(CONFIG_NF_CT_NETLINK) || defined(CONFIG_NF_CT_NETLINK_MODULE)
+ .tuple_to_nfattr = nf_ct_port_tuple_to_nfattr,
+ .nfattr_to_tuple = nf_ct_port_nfattr_to_tuple,
+#endif
+#ifdef CONFIG_SYSCTL
+ .ctl_table_users = &udplite_sysctl_table_users,
+ .ctl_table_header = &udplite_sysctl_header,
+ .ctl_table = udplite_sysctl_table,
+#endif
+};
+
+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,
+ .print_conntrack = udplite_print_conntrack,
+ .packet = udplite_packet,
+ .new = udplite_new,
+ .error = udplite_error,
+#if defined(CONFIG_NF_CT_NETLINK) || defined(CONFIG_NF_CT_NETLINK_MODULE)
+ .tuple_to_nfattr = nf_ct_port_tuple_to_nfattr,
+ .nfattr_to_tuple = nf_ct_port_nfattr_to_tuple,
+#endif
+#ifdef CONFIG_SYSCTL
+ .ctl_table_users = &udplite_sysctl_table_users,
+ .ctl_table_header = &udplite_sysctl_header,
+ .ctl_table = udplite_sysctl_table,
+#endif
+};
+
+static int __init nf_conntrack_proto_udplite_init(void)
+{
+ int err;
+
+ err = nf_conntrack_l4proto_register(&nf_conntrack_l4proto_udplite4);
+ if (err < 0)
+ goto err1;
+ err = nf_conntrack_l4proto_register(&nf_conntrack_l4proto_udplite6);
+ if (err < 0)
+ goto err2;
+ return 0;
+err2:
+ nf_conntrack_l4proto_unregister(&nf_conntrack_l4proto_udplite4);
+err1:
+ return err;
+}
+
+static void __exit nf_conntrack_proto_udplite_exit(void)
+{
+ nf_conntrack_l4proto_unregister(&nf_conntrack_l4proto_udplite6);
+ nf_conntrack_l4proto_unregister(&nf_conntrack_l4proto_udplite4);
+}
+
+module_init(nf_conntrack_proto_udplite_init);
+module_exit(nf_conntrack_proto_udplite_exit);
+
+MODULE_LICENSE("GPL");