--- /dev/null
+/*
+ * Copyright (C)2004 USAGI/WIDE Project
+ *
+ * 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.
+ *
+ * Author:
+ * Yasuyuki Kozakai @USAGI <yasuyuki.kozakai@toshiba.co.jp>
+ *
+ * 16 Dec 2003: Yasuyuki Kozakai @USAGI <yasuyuki.kozakai@toshiba.co.jp>
+ * - support Layer 3 protocol independent connection tracking.
+ * Based on the original ip_conntrack code which had the following
+ * copyright information:
+ * (C) 1999-2001 Paul `Rusty' Russell
+ * (C) 2002-2004 Netfilter Core Team <coreteam@netfilter.org>
+ *
+ * 23 Mar 2004: Yasuyuki Kozakai @USAGI <yasuyuki.kozakai@toshiba.co.jp>
+ * - add get_features() to support various size of conntrack
+ * structures.
+ */
+
+#include <linux/config.h>
+#include <linux/types.h>
+#include <linux/ipv6.h>
+#include <linux/in6.h>
+#include <linux/netfilter.h>
+#include <linux/module.h>
+#include <linux/skbuff.h>
+#include <linux/icmp.h>
+#include <linux/sysctl.h>
+#include <net/ipv6.h>
+
+#include <linux/netfilter_ipv6.h>
+#include <net/netfilter/nf_conntrack.h>
+#include <net/netfilter/nf_conntrack_helper.h>
+#include <net/netfilter/nf_conntrack_protocol.h>
+#include <net/netfilter/nf_conntrack_l3proto.h>
+#include <net/netfilter/nf_conntrack_core.h>
+
+#if 0
+#define DEBUGP printk
+#else
+#define DEBUGP(format, args...)
+#endif
+
+DECLARE_PER_CPU(struct ip_conntrack_stat, nf_conntrack_stat);
+
+static int ipv6_pkt_to_tuple(const struct sk_buff *skb, unsigned int nhoff,
+ struct nf_conntrack_tuple *tuple)
+{
+ u_int32_t _addrs[8], *ap;
+
+ ap = skb_header_pointer(skb, nhoff + offsetof(struct ipv6hdr, saddr),
+ sizeof(_addrs), _addrs);
+ if (ap == NULL)
+ return 0;
+
+ memcpy(tuple->src.u3.ip6, ap, sizeof(tuple->src.u3.ip6));
+ memcpy(tuple->dst.u3.ip6, ap + 4, sizeof(tuple->dst.u3.ip6));
+
+ return 1;
+}
+
+static int ipv6_invert_tuple(struct nf_conntrack_tuple *tuple,
+ const struct nf_conntrack_tuple *orig)
+{
+ memcpy(tuple->src.u3.ip6, orig->dst.u3.ip6, sizeof(tuple->src.u3.ip6));
+ memcpy(tuple->dst.u3.ip6, orig->src.u3.ip6, sizeof(tuple->dst.u3.ip6));
+
+ return 1;
+}
+
+static int ipv6_print_tuple(struct seq_file *s,
+ const struct nf_conntrack_tuple *tuple)
+{
+ return seq_printf(s, "src=" NIP6_FMT " dst=" NIP6_FMT " ",
+ NIP6(*((struct in6_addr *)tuple->src.u3.ip6)),
+ NIP6(*((struct in6_addr *)tuple->dst.u3.ip6)));
+}
+
+static int ipv6_print_conntrack(struct seq_file *s,
+ const struct nf_conn *conntrack)
+{
+ return 0;
+}
+
+/*
+ * Based on ipv6_skip_exthdr() in net/ipv6/exthdr.c
+ *
+ * This function parses (probably truncated) exthdr set "hdr"
+ * of length "len". "nexthdrp" initially points to some place,
+ * where type of the first header can be found.
+ *
+ * It skips all well-known exthdrs, and returns pointer to the start
+ * of unparsable area i.e. the first header with unknown type.
+ * if success, *nexthdr is updated by type/protocol of this header.
+ *
+ * NOTES: - it may return pointer pointing beyond end of packet,
+ * if the last recognized header is truncated in the middle.
+ * - if packet is truncated, so that all parsed headers are skipped,
+ * it returns -1.
+ * - if packet is fragmented, return pointer of the fragment header.
+ * - ESP is unparsable for now and considered like
+ * normal payload protocol.
+ * - Note also special handling of AUTH header. Thanks to IPsec wizards.
+ */
+
+int nf_ct_ipv6_skip_exthdr(struct sk_buff *skb, int start, u8 *nexthdrp,
+ int len)
+{
+ u8 nexthdr = *nexthdrp;
+
+ while (ipv6_ext_hdr(nexthdr)) {
+ struct ipv6_opt_hdr hdr;
+ int hdrlen;
+
+ if (len < (int)sizeof(struct ipv6_opt_hdr))
+ return -1;
+ if (nexthdr == NEXTHDR_NONE)
+ break;
+ if (nexthdr == NEXTHDR_FRAGMENT)
+ break;
+ if (skb_copy_bits(skb, start, &hdr, sizeof(hdr)))
+ BUG();
+ if (nexthdr == NEXTHDR_AUTH)
+ hdrlen = (hdr.hdrlen+2)<<2;
+ else
+ hdrlen = ipv6_optlen(&hdr);
+
+ nexthdr = hdr.nexthdr;
+ len -= hdrlen;
+ start += hdrlen;
+ }
+
+ *nexthdrp = nexthdr;
+ return start;
+}
+
+static int
+ipv6_prepare(struct sk_buff **pskb, unsigned int hooknum, unsigned int *dataoff,
+ u_int8_t *protonum)
+{
+ unsigned int extoff;
+ unsigned char pnum;
+ int protoff;
+
+ extoff = (u8*)((*pskb)->nh.ipv6h + 1) - (*pskb)->data;
+ pnum = (*pskb)->nh.ipv6h->nexthdr;
+
+ protoff = nf_ct_ipv6_skip_exthdr(*pskb, extoff, &pnum,
+ (*pskb)->len - extoff);
+
+ /*
+ * (protoff == (*pskb)->len) mean that the packet doesn't have no data
+ * except of IPv6 & ext headers. but it's tracked anyway. - YK
+ */
+ if ((protoff < 0) || (protoff > (*pskb)->len)) {
+ DEBUGP("ip6_conntrack_core: can't find proto in pkt\n");
+ NF_CT_STAT_INC(error);
+ NF_CT_STAT_INC(invalid);
+ return -NF_ACCEPT;
+ }
+
+ *dataoff = protoff;
+ *protonum = pnum;
+ return NF_ACCEPT;
+}
+
+static u_int32_t ipv6_get_features(const struct nf_conntrack_tuple *tuple)
+{
+ return NF_CT_F_BASIC;
+}
+
+static unsigned int ipv6_confirm(unsigned int hooknum,
+ struct sk_buff **pskb,
+ const struct net_device *in,
+ const struct net_device *out,
+ int (*okfn)(struct sk_buff *))
+{
+ struct nf_conn *ct;
+ struct nf_conn_help *help;
+ enum ip_conntrack_info ctinfo;
+ unsigned int ret, protoff;
+ unsigned int extoff = (u8*)((*pskb)->nh.ipv6h + 1)
+ - (*pskb)->data;
+ unsigned char pnum = (*pskb)->nh.ipv6h->nexthdr;
+
+
+ /* This is where we call the helper: as the packet goes out. */
+ ct = nf_ct_get(*pskb, &ctinfo);
+ if (!ct)
+ goto out;
+
+ help = nfct_help(ct);
+ if (!help || !help->helper)
+ goto out;
+
+ protoff = nf_ct_ipv6_skip_exthdr(*pskb, extoff, &pnum,
+ (*pskb)->len - extoff);
+ if (protoff < 0 || protoff > (*pskb)->len ||
+ pnum == NEXTHDR_FRAGMENT) {
+ DEBUGP("proto header not found\n");
+ return NF_ACCEPT;
+ }
+
+ ret = help->helper->help(pskb, protoff, ct, ctinfo);
+ if (ret != NF_ACCEPT)
+ return ret;
+out:
+ /* We've seen it coming out the other side: confirm it */
+ return nf_conntrack_confirm(pskb);
+}
+
+extern struct sk_buff *nf_ct_frag6_gather(struct sk_buff *skb);
+extern void nf_ct_frag6_output(unsigned int hooknum, struct sk_buff *skb,
+ struct net_device *in,
+ struct net_device *out,
+ int (*okfn)(struct sk_buff *));
+static unsigned int ipv6_defrag(unsigned int hooknum,
+ struct sk_buff **pskb,
+ const struct net_device *in,
+ const struct net_device *out,
+ int (*okfn)(struct sk_buff *))
+{
+ struct sk_buff *reasm;
+
+ /* Previously seen (loopback)? */
+ if ((*pskb)->nfct)
+ return NF_ACCEPT;
+
+ reasm = nf_ct_frag6_gather(*pskb);
+
+ /* queued */
+ if (reasm == NULL)
+ return NF_STOLEN;
+
+ /* error occured or not fragmented */
+ if (reasm == *pskb)
+ return NF_ACCEPT;
+
+ nf_ct_frag6_output(hooknum, reasm, (struct net_device *)in,
+ (struct net_device *)out, okfn);
+
+ return NF_STOLEN;
+}
+
+static unsigned int ipv6_conntrack_in(unsigned int hooknum,
+ struct sk_buff **pskb,
+ const struct net_device *in,
+ const struct net_device *out,
+ int (*okfn)(struct sk_buff *))
+{
+ struct sk_buff *reasm = (*pskb)->nfct_reasm;
+
+ /* This packet is fragmented and has reassembled packet. */
+ if (reasm) {
+ /* Reassembled packet isn't parsed yet ? */
+ if (!reasm->nfct) {
+ unsigned int ret;
+
+ ret = nf_conntrack_in(PF_INET6, hooknum, &reasm);
+ if (ret != NF_ACCEPT)
+ return ret;
+ }
+ nf_conntrack_get(reasm->nfct);
+ (*pskb)->nfct = reasm->nfct;
+ return NF_ACCEPT;
+ }
+
+ return nf_conntrack_in(PF_INET6, hooknum, pskb);
+}
+
+static unsigned int ipv6_conntrack_local(unsigned int hooknum,
+ struct sk_buff **pskb,
+ const struct net_device *in,
+ const struct net_device *out,
+ int (*okfn)(struct sk_buff *))
+{
+ /* root is playing with raw sockets. */
+ if ((*pskb)->len < sizeof(struct ipv6hdr)) {
+ if (net_ratelimit())
+ printk("ipv6_conntrack_local: packet too short\n");
+ return NF_ACCEPT;
+ }
+ return ipv6_conntrack_in(hooknum, pskb, in, out, okfn);
+}
+
+static struct nf_hook_ops ipv6_conntrack_ops[] = {
+ {
+ .hook = ipv6_defrag,
+ .owner = THIS_MODULE,
+ .pf = PF_INET6,
+ .hooknum = NF_IP6_PRE_ROUTING,
+ .priority = NF_IP6_PRI_CONNTRACK_DEFRAG,
+ },
+ {
+ .hook = ipv6_conntrack_in,
+ .owner = THIS_MODULE,
+ .pf = PF_INET6,
+ .hooknum = NF_IP6_PRE_ROUTING,
+ .priority = NF_IP6_PRI_CONNTRACK,
+ },
+ {
+ .hook = ipv6_conntrack_local,
+ .owner = THIS_MODULE,
+ .pf = PF_INET6,
+ .hooknum = NF_IP6_LOCAL_OUT,
+ .priority = NF_IP6_PRI_CONNTRACK,
+ },
+ {
+ .hook = ipv6_defrag,
+ .owner = THIS_MODULE,
+ .pf = PF_INET6,
+ .hooknum = NF_IP6_LOCAL_OUT,
+ .priority = NF_IP6_PRI_CONNTRACK_DEFRAG,
+ },
+ {
+ .hook = ipv6_confirm,
+ .owner = THIS_MODULE,
+ .pf = PF_INET6,
+ .hooknum = NF_IP6_POST_ROUTING,
+ .priority = NF_IP6_PRI_LAST,
+ },
+ {
+ .hook = ipv6_confirm,
+ .owner = THIS_MODULE,
+ .pf = PF_INET6,
+ .hooknum = NF_IP6_LOCAL_IN,
+ .priority = NF_IP6_PRI_LAST-1,
+ },
+};
+
+#ifdef CONFIG_SYSCTL
+
+/* From nf_conntrack_proto_icmpv6.c */
+extern unsigned int nf_ct_icmpv6_timeout;
+
+/* From nf_conntrack_frag6.c */
+extern unsigned int nf_ct_frag6_timeout;
+extern unsigned int nf_ct_frag6_low_thresh;
+extern unsigned int nf_ct_frag6_high_thresh;
+
+static struct ctl_table_header *nf_ct_ipv6_sysctl_header;
+
+static ctl_table nf_ct_sysctl_table[] = {
+ {
+ .ctl_name = NET_NF_CONNTRACK_ICMPV6_TIMEOUT,
+ .procname = "nf_conntrack_icmpv6_timeout",
+ .data = &nf_ct_icmpv6_timeout,
+ .maxlen = sizeof(unsigned int),
+ .mode = 0644,
+ .proc_handler = &proc_dointvec_jiffies,
+ },
+ {
+ .ctl_name = NET_NF_CONNTRACK_FRAG6_TIMEOUT,
+ .procname = "nf_conntrack_frag6_timeout",
+ .data = &nf_ct_frag6_timeout,
+ .maxlen = sizeof(unsigned int),
+ .mode = 0644,
+ .proc_handler = &proc_dointvec_jiffies,
+ },
+ {
+ .ctl_name = NET_NF_CONNTRACK_FRAG6_LOW_THRESH,
+ .procname = "nf_conntrack_frag6_low_thresh",
+ .data = &nf_ct_frag6_low_thresh,
+ .maxlen = sizeof(unsigned int),
+ .mode = 0644,
+ .proc_handler = &proc_dointvec,
+ },
+ {
+ .ctl_name = NET_NF_CONNTRACK_FRAG6_HIGH_THRESH,
+ .procname = "nf_conntrack_frag6_high_thresh",
+ .data = &nf_ct_frag6_high_thresh,
+ .maxlen = sizeof(unsigned int),
+ .mode = 0644,
+ .proc_handler = &proc_dointvec,
+ },
+ { .ctl_name = 0 }
+};
+
+static ctl_table nf_ct_netfilter_table[] = {
+ {
+ .ctl_name = NET_NETFILTER,
+ .procname = "netfilter",
+ .mode = 0555,
+ .child = nf_ct_sysctl_table,
+ },
+ { .ctl_name = 0 }
+};
+
+static ctl_table nf_ct_net_table[] = {
+ {
+ .ctl_name = CTL_NET,
+ .procname = "net",
+ .mode = 0555,
+ .child = nf_ct_netfilter_table,
+ },
+ { .ctl_name = 0 }
+};
+#endif
+
+#if defined(CONFIG_NF_CT_NETLINK) || \
+ defined(CONFIG_NF_CT_NETLINK_MODULE)
+
+#include <linux/netfilter/nfnetlink.h>
+#include <linux/netfilter/nfnetlink_conntrack.h>
+
+static int ipv6_tuple_to_nfattr(struct sk_buff *skb,
+ const struct nf_conntrack_tuple *tuple)
+{
+ NFA_PUT(skb, CTA_IP_V6_SRC, sizeof(u_int32_t) * 4,
+ &tuple->src.u3.ip6);
+ NFA_PUT(skb, CTA_IP_V6_DST, sizeof(u_int32_t) * 4,
+ &tuple->dst.u3.ip6);
+ return 0;
+
+nfattr_failure:
+ return -1;
+}
+
+static const size_t cta_min_ip[CTA_IP_MAX] = {
+ [CTA_IP_V6_SRC-1] = sizeof(u_int32_t)*4,
+ [CTA_IP_V6_DST-1] = sizeof(u_int32_t)*4,
+};
+
+static int ipv6_nfattr_to_tuple(struct nfattr *tb[],
+ struct nf_conntrack_tuple *t)
+{
+ if (!tb[CTA_IP_V6_SRC-1] || !tb[CTA_IP_V6_DST-1])
+ return -EINVAL;
+
+ if (nfattr_bad_size(tb, CTA_IP_MAX, cta_min_ip))
+ return -EINVAL;
+
+ memcpy(&t->src.u3.ip6, NFA_DATA(tb[CTA_IP_V6_SRC-1]),
+ sizeof(u_int32_t) * 4);
+ memcpy(&t->dst.u3.ip6, NFA_DATA(tb[CTA_IP_V6_DST-1]),
+ sizeof(u_int32_t) * 4);
+
+ return 0;
+}
+#endif
+
+struct nf_conntrack_l3proto nf_conntrack_l3proto_ipv6 = {
+ .l3proto = PF_INET6,
+ .name = "ipv6",
+ .pkt_to_tuple = ipv6_pkt_to_tuple,
+ .invert_tuple = ipv6_invert_tuple,
+ .print_tuple = ipv6_print_tuple,
+ .print_conntrack = ipv6_print_conntrack,
+ .prepare = ipv6_prepare,
+#if defined(CONFIG_NF_CT_NETLINK) || \
+ defined(CONFIG_NF_CT_NETLINK_MODULE)
+ .tuple_to_nfattr = ipv6_tuple_to_nfattr,
+ .nfattr_to_tuple = ipv6_nfattr_to_tuple,
+#endif
+ .get_features = ipv6_get_features,
+ .me = THIS_MODULE,
+};
+
+extern struct nf_conntrack_protocol nf_conntrack_protocol_tcp6;
+extern struct nf_conntrack_protocol nf_conntrack_protocol_udp6;
+extern struct nf_conntrack_protocol nf_conntrack_protocol_icmpv6;
+extern int nf_ct_frag6_init(void);
+extern void nf_ct_frag6_cleanup(void);
+
+MODULE_ALIAS("nf_conntrack-" __stringify(AF_INET6));
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Yasuyuki KOZAKAI @USAGI <yasuyuki.kozakai@toshiba.co.jp>");
+
+static int __init nf_conntrack_l3proto_ipv6_init(void)
+{
+ int ret = 0;
+
+ need_conntrack();
+
+ ret = nf_ct_frag6_init();
+ if (ret < 0) {
+ printk("nf_conntrack_ipv6: can't initialize frag6.\n");
+ return ret;
+ }
+ ret = nf_conntrack_protocol_register(&nf_conntrack_protocol_tcp6);
+ if (ret < 0) {
+ printk("nf_conntrack_ipv6: can't register tcp.\n");
+ goto cleanup_frag6;
+ }
+
+ ret = nf_conntrack_protocol_register(&nf_conntrack_protocol_udp6);
+ if (ret < 0) {
+ printk("nf_conntrack_ipv6: can't register udp.\n");
+ goto cleanup_tcp;
+ }
+
+ ret = nf_conntrack_protocol_register(&nf_conntrack_protocol_icmpv6);
+ if (ret < 0) {
+ printk("nf_conntrack_ipv6: can't register icmpv6.\n");
+ goto cleanup_udp;
+ }
+
+ ret = nf_conntrack_l3proto_register(&nf_conntrack_l3proto_ipv6);
+ if (ret < 0) {
+ printk("nf_conntrack_ipv6: can't register ipv6\n");
+ goto cleanup_icmpv6;
+ }
+
+ ret = nf_register_hooks(ipv6_conntrack_ops,
+ ARRAY_SIZE(ipv6_conntrack_ops));
+ if (ret < 0) {
+ printk("nf_conntrack_ipv6: can't register pre-routing defrag "
+ "hook.\n");
+ goto cleanup_ipv6;
+ }
+#ifdef CONFIG_SYSCTL
+ nf_ct_ipv6_sysctl_header = register_sysctl_table(nf_ct_net_table, 0);
+ if (nf_ct_ipv6_sysctl_header == NULL) {
+ printk("nf_conntrack: can't register to sysctl.\n");
+ ret = -ENOMEM;
+ goto cleanup_hooks;
+ }
+#endif
+ return ret;
+
+#ifdef CONFIG_SYSCTL
+ cleanup_hooks:
+ nf_unregister_hooks(ipv6_conntrack_ops, ARRAY_SIZE(ipv6_conntrack_ops));
+#endif
+ cleanup_ipv6:
+ nf_conntrack_l3proto_unregister(&nf_conntrack_l3proto_ipv6);
+ cleanup_icmpv6:
+ nf_conntrack_protocol_unregister(&nf_conntrack_protocol_icmpv6);
+ cleanup_udp:
+ nf_conntrack_protocol_unregister(&nf_conntrack_protocol_udp6);
+ cleanup_tcp:
+ nf_conntrack_protocol_unregister(&nf_conntrack_protocol_tcp6);
+ cleanup_frag6:
+ nf_ct_frag6_cleanup();
+ return ret;
+}
+
+static void __exit nf_conntrack_l3proto_ipv6_fini(void)
+{
+ synchronize_net();
+#ifdef CONFIG_SYSCTL
+ unregister_sysctl_table(nf_ct_ipv6_sysctl_header);
+#endif
+ nf_unregister_hooks(ipv6_conntrack_ops, ARRAY_SIZE(ipv6_conntrack_ops));
+ nf_conntrack_l3proto_unregister(&nf_conntrack_l3proto_ipv6);
+ nf_conntrack_protocol_unregister(&nf_conntrack_protocol_icmpv6);
+ nf_conntrack_protocol_unregister(&nf_conntrack_protocol_udp6);
+ nf_conntrack_protocol_unregister(&nf_conntrack_protocol_tcp6);
+ nf_ct_frag6_cleanup();
+}
+
+module_init(nf_conntrack_l3proto_ipv6_init);
+module_exit(nf_conntrack_l3proto_ipv6_fini);
git://git.onelab.eu / linux-2.6.git / blobdiff