diff --git a/net/netfilter/nf_conntrack_proto_icmpv6.c b/net/netfilter/nf_conntrack_proto_icmpv6.c index facd8c64ec4e..f1a87de1c60e 100644 --- a/net/netfilter/nf_conntrack_proto_icmpv6.c +++ b/net/netfilter/nf_conntrack_proto_icmpv6.c @@ -130,6 +130,56 @@ static void icmpv6_error_log(const struct sk_buff *skb, IPPROTO_ICMPV6, "%s", msg); } +static noinline_for_stack int +nf_conntrack_icmpv6_redirect(struct nf_conn *tmpl, struct sk_buff *skb, + unsigned int dataoff, + const struct nf_hook_state *state) +{ + u8 hl = ipv6_hdr(skb)->hop_limit; + union nf_inet_addr outer_daddr; + union { + struct nd_opt_hdr nd_opt; + struct rd_msg rd_msg; + } tmp; + const struct nd_opt_hdr *nd_opt; + const struct rd_msg *rd_msg; + + rd_msg = skb_header_pointer(skb, dataoff, sizeof(*rd_msg), &tmp.rd_msg); + if (!rd_msg) { + icmpv6_error_log(skb, state, "short redirect"); + return -NF_ACCEPT; + } + + if (rd_msg->icmph.icmp6_code != 0) + return NF_ACCEPT; + + if (hl != 255 || !(ipv6_addr_type(&ipv6_hdr(skb)->saddr) & IPV6_ADDR_LINKLOCAL)) { + icmpv6_error_log(skb, state, "invalid saddr or hoplimit for redirect"); + return -NF_ACCEPT; + } + + dataoff += sizeof(*rd_msg); + + /* warning: rd_msg no longer usable after this call */ + nd_opt = skb_header_pointer(skb, dataoff, sizeof(*nd_opt), &tmp.nd_opt); + if (!nd_opt || nd_opt->nd_opt_len == 0) { + icmpv6_error_log(skb, state, "redirect without options"); + return -NF_ACCEPT; + } + + /* We could call ndisc_parse_options(), but it would need + * skb_linearize() and a bit more work. + */ + if (nd_opt->nd_opt_type != ND_OPT_REDIRECT_HDR) + return NF_ACCEPT; + + memcpy(&outer_daddr.ip6, &ipv6_hdr(skb)->daddr, + sizeof(outer_daddr.ip6)); + dataoff += 8; + return nf_conntrack_inet_error(tmpl, skb, dataoff, state, + IPPROTO_ICMPV6, &outer_daddr); +} + int nf_conntrack_icmpv6_error(struct nf_conn *tmpl, struct sk_buff *skb, unsigned int dataoff, @@ -160,6 +210,9 @@ int nf_conntrack_icmpv6_error(struct nf_conn *tmpl, return NF_ACCEPT; } + if (icmp6h->icmp6_type == NDISC_REDIRECT) + return nf_conntrack_icmpv6_redirect(tmpl, skb, dataoff, state); + /* is not error message ? */ if (icmp6h->icmp6_type >= 128) return NF_ACCEPT; diff --git a/tools/testing/selftests/netfilter/conntrack_icmp_related.sh b/tools/testing/selftests/netfilter/conntrack_icmp_related.sh index b48e1833bc89..76645aaf2b58 100755 --- a/tools/testing/selftests/netfilter/conntrack_icmp_related.sh +++ b/tools/testing/selftests/netfilter/conntrack_icmp_related.sh @@ -35,6 +35,8 @@ cleanup() { for i in 1 2;do ip netns del nsrouter$i;done } +trap cleanup EXIT + ipv4() { echo -n 192.168.$1.2 } @@ -146,11 +148,17 @@ ip netns exec nsclient1 nft -f - < /dev/null + +expect="packets 1 bytes 112" +check_counter nsclient1 "redir4" "$expect" +if [ $? -ne 0 ];then + ret=1 +fi + +ip netns exec "nsclient1" ping -c 1 dead:1::42 > /dev/null +expect="packets 1 bytes 192" +check_counter nsclient1 "redir6" "$expect" +if [ $? -ne 0 ];then + ret=1 +fi + +if [ $ret -eq 0 ];then + echo "PASS: icmp redirects had RELATED state" +else + echo "ERROR: icmp redirect RELATED state test has failed" +fi + exit $ret