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authorEric Dumazet <edumazet@google.com>2015-03-26 01:08:47 +0300
committerDavid S. Miller <davem@davemloft.net>2015-03-29 22:17:18 +0300
commit41d25fe0927aabb1d4b671871a99a55bcd203257 (patch)
tree745072871a02c09835f1b0ca4d8f8472eef17d52 /net/ipv4/tcp_input.c
parent1fb7cd4ef02bea6416b5afd60617d12ceb3533c1 (diff)
downloadlinux-41d25fe0927aabb1d4b671871a99a55bcd203257.tar.xz
tcp: tcp_syn_flood_action() can be static
After commit 1fb6f159fd21 ("tcp: add tcp_conn_request"), tcp_syn_flood_action() is no longer used from IPv6. We can make it static, by moving it above tcp_conn_request() Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Octavian Purdila <octavian.purdila@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/ipv4/tcp_input.c')
-rw-r--r--net/ipv4/tcp_input.c29
1 files changed, 29 insertions, 0 deletions
diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c
index 023196f7ec37..18b80e8bc533 100644
--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c
@@ -5987,6 +5987,35 @@ struct request_sock *inet_reqsk_alloc(const struct request_sock_ops *ops,
}
EXPORT_SYMBOL(inet_reqsk_alloc);
+/*
+ * Return true if a syncookie should be sent
+ */
+static bool tcp_syn_flood_action(struct sock *sk,
+ const struct sk_buff *skb,
+ const char *proto)
+{
+ const char *msg = "Dropping request";
+ bool want_cookie = false;
+ struct listen_sock *lopt;
+
+#ifdef CONFIG_SYN_COOKIES
+ if (sysctl_tcp_syncookies) {
+ msg = "Sending cookies";
+ want_cookie = true;
+ NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_TCPREQQFULLDOCOOKIES);
+ } else
+#endif
+ NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_TCPREQQFULLDROP);
+
+ lopt = inet_csk(sk)->icsk_accept_queue.listen_opt;
+ if (!lopt->synflood_warned && sysctl_tcp_syncookies != 2) {
+ lopt->synflood_warned = 1;
+ pr_info("%s: Possible SYN flooding on port %d. %s. Check SNMP counters.\n",
+ proto, ntohs(tcp_hdr(skb)->dest), msg);
+ }
+ return want_cookie;
+}
+
int tcp_conn_request(struct request_sock_ops *rsk_ops,
const struct tcp_request_sock_ops *af_ops,
struct sock *sk, struct sk_buff *skb)