From 03f1eccc7a69c965351e6bee41c62afa2844752f Mon Sep 17 00:00:00 2001 From: Stephen Suryaputra Date: Tue, 19 Mar 2019 12:37:12 -0400 Subject: ipv6: Add icmp_echo_ignore_multicast support for ICMPv6 IPv4 has icmp_echo_ignore_broadcast to prevent responding to broadcast pings. IPv6 needs a similar mechanism. v1->v2: - Remove NET_IPV6_ICMP_ECHO_IGNORE_MULTICAST. Signed-off-by: Stephen Suryaputra Signed-off-by: David S. Miller --- Documentation/networking/ip-sysctl.txt | 5 +++++ include/net/netns/ipv6.h | 1 + net/ipv6/af_inet6.c | 1 + net/ipv6/icmp.c | 12 ++++++++++++ 4 files changed, 19 insertions(+) diff --git a/Documentation/networking/ip-sysctl.txt b/Documentation/networking/ip-sysctl.txt index acdfb5d2bcaa..55ea7def46be 100644 --- a/Documentation/networking/ip-sysctl.txt +++ b/Documentation/networking/ip-sysctl.txt @@ -1918,6 +1918,11 @@ echo_ignore_all - BOOLEAN requests sent to it over the IPv6 protocol. Default: 0 +echo_ignore_multicast - BOOLEAN + If set non-zero, then the kernel will ignore all ICMP ECHO + requests sent to it over the IPv6 protocol via multicast. + Default: 0 + xfrm6_gc_thresh - INTEGER The threshold at which we will start garbage collecting for IPv6 destination cache entries. At twice this value the system will diff --git a/include/net/netns/ipv6.h b/include/net/netns/ipv6.h index b028a1dc150d..e29aff15acc9 100644 --- a/include/net/netns/ipv6.h +++ b/include/net/netns/ipv6.h @@ -33,6 +33,7 @@ struct netns_sysctl_ipv6 { int auto_flowlabels; int icmpv6_time; int icmpv6_echo_ignore_all; + int icmpv6_echo_ignore_multicast; int anycast_src_echo_reply; int ip_nonlocal_bind; int fwmark_reflect; diff --git a/net/ipv6/af_inet6.c b/net/ipv6/af_inet6.c index 2f45d2a3e3a3..fdc117de849c 100644 --- a/net/ipv6/af_inet6.c +++ b/net/ipv6/af_inet6.c @@ -847,6 +847,7 @@ static int __net_init inet6_net_init(struct net *net) net->ipv6.sysctl.bindv6only = 0; net->ipv6.sysctl.icmpv6_time = 1*HZ; net->ipv6.sysctl.icmpv6_echo_ignore_all = 0; + net->ipv6.sysctl.icmpv6_echo_ignore_multicast = 0; net->ipv6.sysctl.flowlabel_consistency = 1; net->ipv6.sysctl.auto_flowlabels = IP6_DEFAULT_AUTO_FLOW_LABELS; net->ipv6.sysctl.idgen_retries = 3; diff --git a/net/ipv6/icmp.c b/net/ipv6/icmp.c index 802faa2fcc0e..0907bcede5e5 100644 --- a/net/ipv6/icmp.c +++ b/net/ipv6/icmp.c @@ -684,6 +684,10 @@ static void icmpv6_echo_reply(struct sk_buff *skb) struct ipcm6_cookie ipc6; u32 mark = IP6_REPLY_MARK(net, skb->mark); + if (ipv6_addr_is_multicast(&ipv6_hdr(skb)->daddr) && + net->ipv6.sysctl.icmpv6_echo_ignore_multicast) + return; + saddr = &ipv6_hdr(skb)->daddr; if (!ipv6_unicast_destination(skb) && @@ -1115,6 +1119,13 @@ static struct ctl_table ipv6_icmp_table_template[] = { .mode = 0644, .proc_handler = proc_dointvec, }, + { + .procname = "echo_ignore_multicast", + .data = &init_net.ipv6.sysctl.icmpv6_echo_ignore_multicast, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = proc_dointvec, + }, { }, }; @@ -1129,6 +1140,7 @@ struct ctl_table * __net_init ipv6_icmp_sysctl_init(struct net *net) if (table) { table[0].data = &net->ipv6.sysctl.icmpv6_time; table[1].data = &net->ipv6.sysctl.icmpv6_echo_ignore_all; + table[2].data = &net->ipv6.sysctl.icmpv6_echo_ignore_multicast; } return table; } -- cgit v1.2.3-59-g8ed1b