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Diffstat (limited to 'kernel/net/ipv6/netfilter/nf_conntrack_proto_icmpv6.c')
-rw-r--r--kernel/net/ipv6/netfilter/nf_conntrack_proto_icmpv6.c396
1 files changed, 396 insertions, 0 deletions
diff --git a/kernel/net/ipv6/netfilter/nf_conntrack_proto_icmpv6.c b/kernel/net/ipv6/netfilter/nf_conntrack_proto_icmpv6.c
new file mode 100644
index 000000000..90388d606
--- /dev/null
+++ b/kernel/net/ipv6/netfilter/nf_conntrack_proto_icmpv6.c
@@ -0,0 +1,396 @@
+/*
+ * Copyright (C)2003,2004 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>
+ */
+
+#include <linux/types.h>
+#include <linux/timer.h>
+#include <linux/module.h>
+#include <linux/netfilter.h>
+#include <linux/in6.h>
+#include <linux/icmpv6.h>
+#include <linux/ipv6.h>
+#include <net/ipv6.h>
+#include <net/ip6_checksum.h>
+#include <linux/seq_file.h>
+#include <linux/netfilter_ipv6.h>
+#include <net/netfilter/nf_conntrack_tuple.h>
+#include <net/netfilter/nf_conntrack_l4proto.h>
+#include <net/netfilter/nf_conntrack_core.h>
+#include <net/netfilter/nf_conntrack_zones.h>
+#include <net/netfilter/ipv6/nf_conntrack_icmpv6.h>
+#include <net/netfilter/nf_log.h>
+
+static unsigned int nf_ct_icmpv6_timeout __read_mostly = 30*HZ;
+
+static inline struct nf_icmp_net *icmpv6_pernet(struct net *net)
+{
+ return &net->ct.nf_ct_proto.icmpv6;
+}
+
+static bool icmpv6_pkt_to_tuple(const struct sk_buff *skb,
+ unsigned int dataoff,
+ struct nf_conntrack_tuple *tuple)
+{
+ const struct icmp6hdr *hp;
+ struct icmp6hdr _hdr;
+
+ hp = skb_header_pointer(skb, dataoff, sizeof(_hdr), &_hdr);
+ if (hp == NULL)
+ return false;
+ tuple->dst.u.icmp.type = hp->icmp6_type;
+ tuple->src.u.icmp.id = hp->icmp6_identifier;
+ tuple->dst.u.icmp.code = hp->icmp6_code;
+
+ return true;
+}
+
+/* Add 1; spaces filled with 0. */
+static const u_int8_t invmap[] = {
+ [ICMPV6_ECHO_REQUEST - 128] = ICMPV6_ECHO_REPLY + 1,
+ [ICMPV6_ECHO_REPLY - 128] = ICMPV6_ECHO_REQUEST + 1,
+ [ICMPV6_NI_QUERY - 128] = ICMPV6_NI_REPLY + 1,
+ [ICMPV6_NI_REPLY - 128] = ICMPV6_NI_QUERY +1
+};
+
+static const u_int8_t noct_valid_new[] = {
+ [ICMPV6_MGM_QUERY - 130] = 1,
+ [ICMPV6_MGM_REPORT -130] = 1,
+ [ICMPV6_MGM_REDUCTION - 130] = 1,
+ [NDISC_ROUTER_SOLICITATION - 130] = 1,
+ [NDISC_ROUTER_ADVERTISEMENT - 130] = 1,
+ [NDISC_NEIGHBOUR_SOLICITATION - 130] = 1,
+ [NDISC_NEIGHBOUR_ADVERTISEMENT - 130] = 1,
+ [ICMPV6_MLD2_REPORT - 130] = 1
+};
+
+static bool icmpv6_invert_tuple(struct nf_conntrack_tuple *tuple,
+ const struct nf_conntrack_tuple *orig)
+{
+ int type = orig->dst.u.icmp.type - 128;
+ if (type < 0 || type >= sizeof(invmap) || !invmap[type])
+ return false;
+
+ tuple->src.u.icmp.id = orig->src.u.icmp.id;
+ tuple->dst.u.icmp.type = invmap[type] - 1;
+ tuple->dst.u.icmp.code = orig->dst.u.icmp.code;
+ return true;
+}
+
+/* Print out the per-protocol part of the tuple. */
+static void icmpv6_print_tuple(struct seq_file *s,
+ const struct nf_conntrack_tuple *tuple)
+{
+ seq_printf(s, "type=%u code=%u id=%u ",
+ tuple->dst.u.icmp.type,
+ tuple->dst.u.icmp.code,
+ ntohs(tuple->src.u.icmp.id));
+}
+
+static unsigned int *icmpv6_get_timeouts(struct net *net)
+{
+ return &icmpv6_pernet(net)->timeout;
+}
+
+/* Returns verdict for packet, or -1 for invalid. */
+static int icmpv6_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 *timeout)
+{
+ /* Do not immediately delete the connection after the first
+ successful reply to avoid excessive conntrackd traffic
+ and also to handle correctly ICMP echo reply duplicates. */
+ nf_ct_refresh_acct(ct, ctinfo, skb, *timeout);
+
+ return NF_ACCEPT;
+}
+
+/* Called when a new connection for this protocol found. */
+static bool icmpv6_new(struct nf_conn *ct, const struct sk_buff *skb,
+ unsigned int dataoff, unsigned int *timeouts)
+{
+ static const u_int8_t valid_new[] = {
+ [ICMPV6_ECHO_REQUEST - 128] = 1,
+ [ICMPV6_NI_QUERY - 128] = 1
+ };
+ int type = ct->tuplehash[0].tuple.dst.u.icmp.type - 128;
+
+ if (type < 0 || type >= sizeof(valid_new) || !valid_new[type]) {
+ /* Can't create a new ICMPv6 `conn' with this. */
+ pr_debug("icmpv6: can't create new conn with type %u\n",
+ type + 128);
+ nf_ct_dump_tuple_ipv6(&ct->tuplehash[0].tuple);
+ if (LOG_INVALID(nf_ct_net(ct), IPPROTO_ICMPV6))
+ nf_log_packet(nf_ct_net(ct), PF_INET6, 0, skb, NULL,
+ NULL, NULL,
+ "nf_ct_icmpv6: invalid new with type %d ",
+ type + 128);
+ return false;
+ }
+ return true;
+}
+
+static int
+icmpv6_error_message(struct net *net, struct nf_conn *tmpl,
+ struct sk_buff *skb,
+ unsigned int icmp6off,
+ enum ip_conntrack_info *ctinfo,
+ unsigned int hooknum)
+{
+ struct nf_conntrack_tuple intuple, origtuple;
+ const struct nf_conntrack_tuple_hash *h;
+ const struct nf_conntrack_l4proto *inproto;
+ u16 zone = tmpl ? nf_ct_zone(tmpl) : NF_CT_DEFAULT_ZONE;
+
+ NF_CT_ASSERT(skb->nfct == NULL);
+
+ /* Are they talking about one of our connections? */
+ if (!nf_ct_get_tuplepr(skb,
+ skb_network_offset(skb)
+ + sizeof(struct ipv6hdr)
+ + sizeof(struct icmp6hdr),
+ PF_INET6, &origtuple)) {
+ pr_debug("icmpv6_error: Can't get tuple\n");
+ return -NF_ACCEPT;
+ }
+
+ /* rcu_read_lock()ed by nf_hook_slow */
+ inproto = __nf_ct_l4proto_find(PF_INET6, origtuple.dst.protonum);
+
+ /* Ordinarily, we'd expect the inverted tupleproto, but it's
+ been preserved inside the ICMP. */
+ if (!nf_ct_invert_tuple(&intuple, &origtuple,
+ &nf_conntrack_l3proto_ipv6, inproto)) {
+ pr_debug("icmpv6_error: Can't invert tuple\n");
+ return -NF_ACCEPT;
+ }
+
+ *ctinfo = IP_CT_RELATED;
+
+ h = nf_conntrack_find_get(net, zone, &intuple);
+ if (!h) {
+ pr_debug("icmpv6_error: no match\n");
+ return -NF_ACCEPT;
+ } else {
+ if (NF_CT_DIRECTION(h) == IP_CT_DIR_REPLY)
+ *ctinfo += IP_CT_IS_REPLY;
+ }
+
+ /* Update skb to refer to this connection */
+ skb->nfct = &nf_ct_tuplehash_to_ctrack(h)->ct_general;
+ skb->nfctinfo = *ctinfo;
+ return NF_ACCEPT;
+}
+
+static int
+icmpv6_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)
+{
+ const struct icmp6hdr *icmp6h;
+ struct icmp6hdr _ih;
+ int type;
+
+ icmp6h = skb_header_pointer(skb, dataoff, sizeof(_ih), &_ih);
+ if (icmp6h == NULL) {
+ if (LOG_INVALID(net, IPPROTO_ICMPV6))
+ nf_log_packet(net, PF_INET6, 0, skb, NULL, NULL, NULL,
+ "nf_ct_icmpv6: short packet ");
+ return -NF_ACCEPT;
+ }
+
+ if (net->ct.sysctl_checksum && hooknum == NF_INET_PRE_ROUTING &&
+ nf_ip6_checksum(skb, hooknum, dataoff, IPPROTO_ICMPV6)) {
+ if (LOG_INVALID(net, IPPROTO_ICMPV6))
+ nf_log_packet(net, PF_INET6, 0, skb, NULL, NULL, NULL,
+ "nf_ct_icmpv6: ICMPv6 checksum failed ");
+ return -NF_ACCEPT;
+ }
+
+ type = icmp6h->icmp6_type - 130;
+ if (type >= 0 && type < sizeof(noct_valid_new) &&
+ noct_valid_new[type]) {
+ skb->nfct = &nf_ct_untracked_get()->ct_general;
+ skb->nfctinfo = IP_CT_NEW;
+ nf_conntrack_get(skb->nfct);
+ return NF_ACCEPT;
+ }
+
+ /* is not error message ? */
+ if (icmp6h->icmp6_type >= 128)
+ return NF_ACCEPT;
+
+ return icmpv6_error_message(net, tmpl, skb, dataoff, ctinfo, hooknum);
+}
+
+#if IS_ENABLED(CONFIG_NF_CT_NETLINK)
+
+#include <linux/netfilter/nfnetlink.h>
+#include <linux/netfilter/nfnetlink_conntrack.h>
+static int icmpv6_tuple_to_nlattr(struct sk_buff *skb,
+ const struct nf_conntrack_tuple *t)
+{
+ if (nla_put_be16(skb, CTA_PROTO_ICMPV6_ID, t->src.u.icmp.id) ||
+ nla_put_u8(skb, CTA_PROTO_ICMPV6_TYPE, t->dst.u.icmp.type) ||
+ nla_put_u8(skb, CTA_PROTO_ICMPV6_CODE, t->dst.u.icmp.code))
+ goto nla_put_failure;
+ return 0;
+
+nla_put_failure:
+ return -1;
+}
+
+static const struct nla_policy icmpv6_nla_policy[CTA_PROTO_MAX+1] = {
+ [CTA_PROTO_ICMPV6_TYPE] = { .type = NLA_U8 },
+ [CTA_PROTO_ICMPV6_CODE] = { .type = NLA_U8 },
+ [CTA_PROTO_ICMPV6_ID] = { .type = NLA_U16 },
+};
+
+static int icmpv6_nlattr_to_tuple(struct nlattr *tb[],
+ struct nf_conntrack_tuple *tuple)
+{
+ if (!tb[CTA_PROTO_ICMPV6_TYPE] ||
+ !tb[CTA_PROTO_ICMPV6_CODE] ||
+ !tb[CTA_PROTO_ICMPV6_ID])
+ return -EINVAL;
+
+ tuple->dst.u.icmp.type = nla_get_u8(tb[CTA_PROTO_ICMPV6_TYPE]);
+ tuple->dst.u.icmp.code = nla_get_u8(tb[CTA_PROTO_ICMPV6_CODE]);
+ tuple->src.u.icmp.id = nla_get_be16(tb[CTA_PROTO_ICMPV6_ID]);
+
+ if (tuple->dst.u.icmp.type < 128 ||
+ tuple->dst.u.icmp.type - 128 >= sizeof(invmap) ||
+ !invmap[tuple->dst.u.icmp.type - 128])
+ return -EINVAL;
+
+ return 0;
+}
+
+static int icmpv6_nlattr_tuple_size(void)
+{
+ return nla_policy_len(icmpv6_nla_policy, CTA_PROTO_MAX + 1);
+}
+#endif
+
+#if IS_ENABLED(CONFIG_NF_CT_NETLINK_TIMEOUT)
+
+#include <linux/netfilter/nfnetlink.h>
+#include <linux/netfilter/nfnetlink_cttimeout.h>
+
+static int icmpv6_timeout_nlattr_to_obj(struct nlattr *tb[],
+ struct net *net, void *data)
+{
+ unsigned int *timeout = data;
+ struct nf_icmp_net *in = icmpv6_pernet(net);
+
+ if (tb[CTA_TIMEOUT_ICMPV6_TIMEOUT]) {
+ *timeout =
+ ntohl(nla_get_be32(tb[CTA_TIMEOUT_ICMPV6_TIMEOUT])) * HZ;
+ } else {
+ /* Set default ICMPv6 timeout. */
+ *timeout = in->timeout;
+ }
+ return 0;
+}
+
+static int
+icmpv6_timeout_obj_to_nlattr(struct sk_buff *skb, const void *data)
+{
+ const unsigned int *timeout = data;
+
+ if (nla_put_be32(skb, CTA_TIMEOUT_ICMPV6_TIMEOUT, htonl(*timeout / HZ)))
+ goto nla_put_failure;
+ return 0;
+
+nla_put_failure:
+ return -ENOSPC;
+}
+
+static const struct nla_policy
+icmpv6_timeout_nla_policy[CTA_TIMEOUT_ICMPV6_MAX+1] = {
+ [CTA_TIMEOUT_ICMPV6_TIMEOUT] = { .type = NLA_U32 },
+};
+#endif /* CONFIG_NF_CT_NETLINK_TIMEOUT */
+
+#ifdef CONFIG_SYSCTL
+static struct ctl_table icmpv6_sysctl_table[] = {
+ {
+ .procname = "nf_conntrack_icmpv6_timeout",
+ .maxlen = sizeof(unsigned int),
+ .mode = 0644,
+ .proc_handler = proc_dointvec_jiffies,
+ },
+ { }
+};
+#endif /* CONFIG_SYSCTL */
+
+static int icmpv6_kmemdup_sysctl_table(struct nf_proto_net *pn,
+ struct nf_icmp_net *in)
+{
+#ifdef CONFIG_SYSCTL
+ pn->ctl_table = kmemdup(icmpv6_sysctl_table,
+ sizeof(icmpv6_sysctl_table),
+ GFP_KERNEL);
+ if (!pn->ctl_table)
+ return -ENOMEM;
+
+ pn->ctl_table[0].data = &in->timeout;
+#endif
+ return 0;
+}
+
+static int icmpv6_init_net(struct net *net, u_int16_t proto)
+{
+ struct nf_icmp_net *in = icmpv6_pernet(net);
+ struct nf_proto_net *pn = &in->pn;
+
+ in->timeout = nf_ct_icmpv6_timeout;
+
+ return icmpv6_kmemdup_sysctl_table(pn, in);
+}
+
+static struct nf_proto_net *icmpv6_get_net_proto(struct net *net)
+{
+ return &net->ct.nf_ct_proto.icmpv6.pn;
+}
+
+struct nf_conntrack_l4proto nf_conntrack_l4proto_icmpv6 __read_mostly =
+{
+ .l3proto = PF_INET6,
+ .l4proto = IPPROTO_ICMPV6,
+ .name = "icmpv6",
+ .pkt_to_tuple = icmpv6_pkt_to_tuple,
+ .invert_tuple = icmpv6_invert_tuple,
+ .print_tuple = icmpv6_print_tuple,
+ .packet = icmpv6_packet,
+ .get_timeouts = icmpv6_get_timeouts,
+ .new = icmpv6_new,
+ .error = icmpv6_error,
+#if IS_ENABLED(CONFIG_NF_CT_NETLINK)
+ .tuple_to_nlattr = icmpv6_tuple_to_nlattr,
+ .nlattr_tuple_size = icmpv6_nlattr_tuple_size,
+ .nlattr_to_tuple = icmpv6_nlattr_to_tuple,
+ .nla_policy = icmpv6_nla_policy,
+#endif
+#if IS_ENABLED(CONFIG_NF_CT_NETLINK_TIMEOUT)
+ .ctnl_timeout = {
+ .nlattr_to_obj = icmpv6_timeout_nlattr_to_obj,
+ .obj_to_nlattr = icmpv6_timeout_obj_to_nlattr,
+ .nlattr_max = CTA_TIMEOUT_ICMP_MAX,
+ .obj_size = sizeof(unsigned int),
+ .nla_policy = icmpv6_timeout_nla_policy,
+ },
+#endif /* CONFIG_NF_CT_NETLINK_TIMEOUT */
+ .init_net = icmpv6_init_net,
+ .get_net_proto = icmpv6_get_net_proto,
+};