[NETFILTER]: conntrack: add sysctl to disable checksumming

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

5 files changed, 15 insertions, 4 deletions

diff --git a/net/ipv4/netfilter/ip_conntrack_proto_icmp.c b/net/ipv4/netfilter/ip_conntrack_proto_icmp.c
index d8b14a9010a6..23f1c504586d 100644
--- a/net/ipv4/netfilter/ip_conntrack_proto_icmp.c
+++ b/net/ipv4/netfilter/ip_conntrack_proto_icmp.c
@@ -224,7 +224,7 @@ icmp_error(struct sk_buff *skb, enum ip_conntrack_info *ctinfo,
         }
 
         /* See ip_conntrack_proto_tcp.c */
-        if (hooknum == NF_IP_PRE_ROUTING &&
+        if (ip_conntrack_checksum && hooknum == NF_IP_PRE_ROUTING &&
             nf_ip_checksum(skb, hooknum, skb->nh.iph->ihl * 4, 0)) {
                 if (LOG_INVALID(IPPROTO_ICMP))
                         nf_log_packet(PF_INET, 0, skb, NULL, NULL, NULL,
diff --git a/net/ipv4/netfilter/ip_conntrack_proto_tcp.c b/net/ipv4/netfilter/ip_conntrack_proto_tcp.c
index 062b252b58ad..c5c2ce5cdeb8 100644
--- a/net/ipv4/netfilter/ip_conntrack_proto_tcp.c
+++ b/net/ipv4/netfilter/ip_conntrack_proto_tcp.c
@@ -870,7 +870,7 @@ static int tcp_error(struct sk_buff *skb,
          * and moreover root might send raw packets.
          */
         /* FIXME: Source route IP option packets --RR */
-        if (hooknum == NF_IP_PRE_ROUTING &&
+        if (ip_conntrack_checksum && hooknum == NF_IP_PRE_ROUTING &&
             nf_ip_checksum(skb, hooknum, iph->ihl * 4, IPPROTO_TCP)) {
                 if (LOG_INVALID(IPPROTO_TCP))
                         nf_log_packet(PF_INET, 0, skb, NULL, NULL, NULL,
diff --git a/net/ipv4/netfilter/ip_conntrack_proto_udp.c b/net/ipv4/netfilter/ip_conntrack_proto_udp.c
index 70899868783b..9b2c16b4d2ff 100644
--- a/net/ipv4/netfilter/ip_conntrack_proto_udp.c
+++ b/net/ipv4/netfilter/ip_conntrack_proto_udp.c
@@ -120,7 +120,7 @@ static int udp_error(struct sk_buff *skb, enum ip_conntrack_info *ctinfo,
          * because the semantic of CHECKSUM_HW is different there 
          * and moreover root might send raw packets.
          * FIXME: Source route IP option packets --RR */
-        if (hooknum == NF_IP_PRE_ROUTING &&
+        if (ip_conntrack_checksum && hooknum == NF_IP_PRE_ROUTING &&
             nf_ip_checksum(skb, hooknum, iph->ihl * 4, IPPROTO_UDP)) {
                 if (LOG_INVALID(IPPROTO_UDP))
                         nf_log_packet(PF_INET, 0, skb, NULL, NULL, NULL,
diff --git a/net/ipv4/netfilter/ip_conntrack_standalone.c b/net/ipv4/netfilter/ip_conntrack_standalone.c
index f0cc7feb0da3..6cb9b989d14c 100644
--- a/net/ipv4/netfilter/ip_conntrack_standalone.c
+++ b/net/ipv4/netfilter/ip_conntrack_standalone.c
@@ -564,6 +564,8 @@ extern unsigned int ip_ct_generic_timeout;
 static int log_invalid_proto_min = 0;
 static int log_invalid_proto_max = 255;
 
+int ip_conntrack_checksum = 1;
+
 static struct ctl_table_header *ip_ct_sysctl_header;
 
 static ctl_table ip_ct_sysctl_table[] = {
@@ -592,6 +594,14 @@ static ctl_table ip_ct_sysctl_table[] = {
                 .proc_handler   = &proc_dointvec,
         },
         {
+                .ctl_name       = NET_IPV4_NF_CONNTRACK_CHECKSUM,
+                .procname       = "ip_conntrack_checksum",
+                .data           = &ip_conntrack_checksum,
+                .maxlen         = sizeof(int),
+                .mode           = 0644,
+                .proc_handler   = &proc_dointvec,
+        },
+        {
                 .ctl_name       = NET_IPV4_NF_CONNTRACK_TCP_TIMEOUT_SYN_SENT,
                 .procname       = "ip_conntrack_tcp_timeout_syn_sent",
                 .data           = &ip_ct_tcp_timeout_syn_sent,
@@ -946,6 +956,7 @@ EXPORT_SYMBOL_GPL(__ip_conntrack_helper_find_byname);
 EXPORT_SYMBOL_GPL(ip_conntrack_proto_find_get);
 EXPORT_SYMBOL_GPL(ip_conntrack_proto_put);
 EXPORT_SYMBOL_GPL(__ip_conntrack_proto_find);
+EXPORT_SYMBOL_GPL(ip_conntrack_checksum);
 #if defined(CONFIG_IP_NF_CONNTRACK_NETLINK) || \
     defined(CONFIG_IP_NF_CONNTRACK_NETLINK_MODULE)
 EXPORT_SYMBOL_GPL(ip_ct_port_tuple_to_nfattr);
diff --git a/net/ipv4/netfilter/nf_conntrack_proto_icmp.c b/net/ipv4/netfilter/nf_conntrack_proto_icmp.c
index 4b0d361cc6e6..663a73ee3f2f 100644
--- a/net/ipv4/netfilter/nf_conntrack_proto_icmp.c
+++ b/net/ipv4/netfilter/nf_conntrack_proto_icmp.c
@@ -235,7 +235,7 @@ icmp_error(struct sk_buff *skb, unsigned int dataoff,
         }
 
         /* See ip_conntrack_proto_tcp.c */
-        if (hooknum == NF_IP_PRE_ROUTING &&
+        if (nf_conntrack_checksum && hooknum == NF_IP_PRE_ROUTING &&
             nf_ip_checksum(skb, hooknum, dataoff, 0)) {
                 if (LOG_INVALID(IPPROTO_ICMP))
                         nf_log_packet(PF_INET, 0, skb, NULL, NULL, NULL,