ipvs: sloppy TCP and SCTP

This adds support for sloppy TCP and SCTP modes to IPVS.

When enabled (sysctls net.ipv4.vs.sloppy_tcp and
net.ipv4.vs.sloppy_sctp), allows IPVS to create connection state on any
packet, not just a TCP SYN (or SCTP INIT).

This allows connections to fail over from one IPVS director to another
mid-flight.

Signed-off-by: Alexander Frolkin <avf@eldamar.org.uk>
Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Simon Horman <horms@verge.net.au>

1 files changed, 24 insertions, 0 deletions

diff --git a/include/net/ip_vs.h b/include/net/ip_vs.h
index f5faf859876e..95860dfdfbe3 100644
--- a/include/net/ip_vs.h
+++ b/include/net/ip_vs.h
@@ -978,6 +978,8 @@ struct netns_ipvs {
         int                     sysctl_sync_sock_size;
         int                     sysctl_cache_bypass;
         int                     sysctl_expire_nodest_conn;
+        int                     sysctl_sloppy_tcp;
+        int                     sysctl_sloppy_sctp;
         int                     sysctl_expire_quiescent_template;
         int                     sysctl_sync_threshold[2];
         unsigned int            sysctl_sync_refresh_period;
@@ -1020,6 +1022,8 @@ struct netns_ipvs {
 #define DEFAULT_SYNC_THRESHOLD  3
 #define DEFAULT_SYNC_PERIOD     50
 #define DEFAULT_SYNC_VER        1
+#define DEFAULT_SLOPPY_TCP      0
+#define DEFAULT_SLOPPY_SCTP     0
 #define DEFAULT_SYNC_REFRESH_PERIOD     (0U * HZ)
 #define DEFAULT_SYNC_RETRIES            0
 #define IPVS_SYNC_WAKEUP_RATE   8
@@ -1056,6 +1060,16 @@ static inline int sysctl_sync_ver(struct netns_ipvs *ipvs)
         return ipvs->sysctl_sync_ver;
 }
 
+static inline int sysctl_sloppy_tcp(struct netns_ipvs *ipvs)
+{
+        return ipvs->sysctl_sloppy_tcp;
+}
+
+static inline int sysctl_sloppy_sctp(struct netns_ipvs *ipvs)
+{
+        return ipvs->sysctl_sloppy_sctp;
+}
+
 static inline int sysctl_sync_ports(struct netns_ipvs *ipvs)
 {
         return ACCESS_ONCE(ipvs->sysctl_sync_ports);
@@ -1109,6 +1123,16 @@ static inline int sysctl_sync_ver(struct netns_ipvs *ipvs)
         return DEFAULT_SYNC_VER;
 }
 
+static inline int sysctl_sloppy_tcp(struct netns_ipvs *ipvs)
+{
+        return DEFAULT_SLOPPY_TCP;
+}
+
+static inline int sysctl_sloppy_sctp(struct netns_ipvs *ipvs)
+{
+        return DEFAULT_SLOPPY_SCTP;
+}
+
 static inline int sysctl_sync_ports(struct netns_ipvs *ipvs)
 {
         return 1;