--- /dev/null
+/* (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");
Code Review / kvmfornfv.git / blobdiff