tcp: MD5: Use MIB counter instead of warning for MD5 mismatch.

From a report by Matti Aarnio, and preliminary patch by Adam Langley.

Signed-off-by: David S. Miller <davem@davemloft.net>

4 files changed, 14 insertions, 27 deletions

diff --git a/include/linux/snmp.h b/include/linux/snmp.h
index 5df62ef1280c..7a6e6bba4a71 100644
--- a/include/linux/snmp.h
+++ b/include/linux/snmp.h
@@ -214,6 +214,8 @@ enum
         LINUX_MIB_TCPDSACKIGNOREDOLD,           /* TCPSACKIgnoredOld */
         LINUX_MIB_TCPDSACKIGNOREDNOUNDO,        /* TCPSACKIgnoredNoUndo */
         LINUX_MIB_TCPSPURIOUSRTOS,              /* TCPSpuriousRTOs */
+        LINUX_MIB_TCPMD5NOTFOUND,               /* TCPMD5NotFound */
+        LINUX_MIB_TCPMD5UNEXPECTED,             /* TCPMD5Unexpected */
         __LINUX_MIB_MAX
 };
 
diff --git a/net/ipv4/proc.c b/net/ipv4/proc.c
index 834356ea99df..8f5a403f6f6b 100644
--- a/net/ipv4/proc.c
+++ b/net/ipv4/proc.c
@@ -232,6 +232,8 @@ static const struct snmp_mib snmp4_net_list[] = {
         SNMP_MIB_ITEM("TCPDSACKIgnoredOld", LINUX_MIB_TCPDSACKIGNOREDOLD),
         SNMP_MIB_ITEM("TCPDSACKIgnoredNoUndo", LINUX_MIB_TCPDSACKIGNOREDNOUNDO),
         SNMP_MIB_ITEM("TCPSpuriousRTOs", LINUX_MIB_TCPSPURIOUSRTOS),
+        SNMP_MIB_ITEM("TCPMD5NotFound", LINUX_MIB_TCPMD5NOTFOUND),
+        SNMP_MIB_ITEM("TCPMD5Unexpected", LINUX_MIB_TCPMD5UNEXPECTED),
         SNMP_MIB_SENTINEL
 };
 
diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c
index a2b06d0cc26b..b3875c0d83c7 100644
--- a/net/ipv4/tcp_ipv4.c
+++ b/net/ipv4/tcp_ipv4.c
@@ -1116,18 +1116,12 @@ static int tcp_v4_inbound_md5_hash(struct sock *sk, struct sk_buff *skb)
                 return 0;
 
         if (hash_expected && !hash_location) {
-                LIMIT_NETDEBUG(KERN_INFO "MD5 Hash expected but NOT found "
-                               "(" NIPQUAD_FMT ", %d)->(" NIPQUAD_FMT ", %d)\n",
-                               NIPQUAD(iph->saddr), ntohs(th->source),
-                               NIPQUAD(iph->daddr), ntohs(th->dest));
+                NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_TCPMD5NOTFOUND);
                 return 1;
         }
 
         if (!hash_expected && hash_location) {
-                LIMIT_NETDEBUG(KERN_INFO "MD5 Hash NOT expected but found "
-                               "(" NIPQUAD_FMT ", %d)->(" NIPQUAD_FMT ", %d)\n",
-                               NIPQUAD(iph->saddr), ntohs(th->source),
-                               NIPQUAD(iph->daddr), ntohs(th->dest));
+                NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_TCPMD5UNEXPECTED);
                 return 1;
         }
 
diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c
index cff778b23a7f..1db45216b232 100644
--- a/net/ipv6/tcp_ipv6.c
+++ b/net/ipv6/tcp_ipv6.c
@@ -849,28 +849,17 @@ static int tcp_v6_inbound_md5_hash (struct sock *sk, struct sk_buff *skb)
         hash_expected = tcp_v6_md5_do_lookup(sk, &ip6h->saddr);
         hash_location = tcp_parse_md5sig_option(th);
 
-        /* do we have a hash as expected? */
-        if (!hash_expected) {
-                if (!hash_location)
-                        return 0;
-                if (net_ratelimit()) {
-                        printk(KERN_INFO "MD5 Hash NOT expected but found "
-                               "(" NIP6_FMT ", %u)->"
-                               "(" NIP6_FMT ", %u)\n",
-                               NIP6(ip6h->saddr), ntohs(th->source),
-                               NIP6(ip6h->daddr), ntohs(th->dest));
-                }
+        /* We've parsed the options - do we have a hash? */
+        if (!hash_expected && !hash_location)
+                return 0;
+
+        if (hash_expected && !hash_location) {
+                NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_TCPMD5NOTFOUND);
                 return 1;
         }
 
-        if (!hash_location) {
-                if (net_ratelimit()) {
-                        printk(KERN_INFO "MD5 Hash expected but NOT found "
-                               "(" NIP6_FMT ", %u)->"
-                               "(" NIP6_FMT ", %u)\n",
-                               NIP6(ip6h->saddr), ntohs(th->source),
-                               NIP6(ip6h->daddr), ntohs(th->dest));
-                }
+        if (!hash_expected && hash_location) {
+                NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_TCPMD5UNEXPECTED);
                 return 1;
         }