[PATCH 3/3] net/colo-compare: Add handler for passthrough connection

[Zhang Chen <chen.zhang@intel.com >]

From: Zhang Chen <chen.zhang@intel.com>

Currently, we just use guest's TCP/UDP source port as the key
to bypass certain network traffic.

Signed-off-by: Zhang Chen <chen.zhang@intel.com>
---
 net/colo-compare.c | 49 ++++++++++++++++++++++++++++++++++++++++++++++
 net/colo-compare.h |  2 ++
 net/net.c          | 27 +++++++++++++++++++++++++
 3 files changed, 78 insertions(+)

diff --git a/net/colo-compare.c b/net/colo-compare.c
index 337025b44f..11a32caa9b 100644
--- a/net/colo-compare.c
+++ b/net/colo-compare.c
@@ -46,6 +46,9 @@ static QTAILQ_HEAD(, CompareState) net_compares =
 static NotifierList colo_compare_notifiers =
     NOTIFIER_LIST_INITIALIZER(colo_compare_notifiers);
 
+static QLIST_HEAD(, PassthroughEntry) passthroughlist =
+    QLIST_HEAD_INITIALIZER(passthroughlist);
+
 #define COMPARE_READ_LEN_MAX NET_BUFSIZE
 #define MAX_QUEUE_SIZE 1024
 
@@ -103,6 +106,12 @@ typedef struct SendEntry {
     uint8_t *buf;
 } SendEntry;
 
+typedef struct PassthroughEntry {
+    bool is_tcp;
+    uint16_t port;
+    QLIST_ENTRY(PassthroughEntry) node;
+} PassthroughEntry;
+
 struct CompareState {
     Object parent;
 
@@ -247,6 +256,7 @@ static int packet_enqueue(CompareState *s, int mode, Connection **con)
     ConnectionKey key;
     Packet *pkt = NULL;
     Connection *conn;
+    PassthroughEntry *bypass, *next;
     int ret;
 
     if (mode == PRIMARY_IN) {
@@ -264,8 +274,23 @@ static int packet_enqueue(CompareState *s, int mode, Connection **con)
         pkt = NULL;
         return -1;
     }
+
     fill_connection_key(pkt, &key);
 
+    /* Check COLO passthrough connenction */
+    if (!QLIST_EMPTY(&passthroughlist)) {
+        QLIST_FOREACH_SAFE(bypass, &passthroughlist, node, next) {
+            if (((key.ip_proto == IPPROTO_TCP) && bypass->is_tcp) ||
+                ((key.ip_proto == IPPROTO_UDP) && !bypass->is_tcp)) {
+                if (bypass->port == key.src_port) {
+                    packet_destroy(pkt, NULL);
+                    pkt = NULL;
+                    return -1;
+                }
+            }
+        }
+    }
+
     conn = connection_get(s->connection_track_table,
                           &key,
                           &s->conn_list);
@@ -1373,6 +1398,30 @@ static void colo_flush_packets(void *opaque, void *user_data)
     }
 }
 
+void colo_compare_passthrough_add(bool is_tcp, const uint16_t port)
+{
+    PassthroughEntry *bypass = NULL;
+
+    bypass = g_new0(PassthroughEntry, 1);
+    bypass->is_tcp = is_tcp;
+    bypass->port = port;
+    QLIST_INSERT_HEAD(&passthroughlist, bypass, node);
+}
+
+void colo_compare_passthrough_del(bool is_tcp, const uint16_t port)
+{
+    PassthroughEntry *bypass = NULL, *next = NULL;
+
+    if (!QLIST_EMPTY(&passthroughlist)) {
+        QLIST_FOREACH_SAFE(bypass, &passthroughlist, node, next) {
+            if ((bypass->is_tcp == is_tcp) && (bypass->port == port)) {
+                QLIST_REMOVE(bypass, node);
+                g_free(bypass);
+            }
+        }
+    }
+}
+
 static void colo_compare_class_init(ObjectClass *oc, void *data)
 {
     UserCreatableClass *ucc = USER_CREATABLE_CLASS(oc);
diff --git a/net/colo-compare.h b/net/colo-compare.h
index 22ddd512e2..1fa026c85e 100644
--- a/net/colo-compare.h
+++ b/net/colo-compare.h
@@ -20,5 +20,7 @@
 void colo_notify_compares_event(void *opaque, int event, Error **errp);
 void colo_compare_register_notifier(Notifier *notify);
 void colo_compare_unregister_notifier(Notifier *notify);
+void colo_compare_passthrough_add(bool is_tcp, const uint16_t port);
+void colo_compare_passthrough_del(bool is_tcp, const uint16_t port);
 
 #endif /* QEMU_COLO_COMPARE_H */
diff --git a/net/net.c b/net/net.c
index eac7a92618..1f303e8309 100644
--- a/net/net.c
+++ b/net/net.c
@@ -55,6 +55,7 @@
 #include "sysemu/sysemu.h"
 #include "net/filter.h"
 #include "qapi/string-output-visitor.h"
+#include "net/colo-compare.h"
 
 /* Net bridge is currently not supported for W32. */
 #if !defined(_WIN32)
@@ -1155,12 +1156,38 @@ void qmp_colo_passthrough_add(const char *prot, const uint32_t port,
                               Error **errp)
 {
     /* Setup passthrough connection */
+    if (port > 65536) {
+        error_setg(errp, "COLO pass through get wrong port");
+        return;
+    }
+
+    if (!strcmp(prot, "tcp") || !strcmp(prot, "TCP")) {
+        colo_compare_passthrough_add(true, (uint16_t)port);
+    } else if (!strcmp(prot, "udp") || !strcmp(prot, "UDP")) {
+        colo_compare_passthrough_add(false, (uint16_t)port);
+    } else {
+        error_setg(errp, "COLO pass through just support tcp or udp protocol");
+        return;
+    }
 }
 
 void qmp_colo_passthrough_del(const char *prot, const uint32_t port,
                               Error **errp)
 {
     /* Delete passthrough connection */
+    if (port > 65536) {
+        error_setg(errp, "COLO pass through get wrong port");
+        return;
+    }
+
+    if (!strcmp(prot, "tcp") || !strcmp(prot, "TCP")) {
+        colo_compare_passthrough_del(true, (uint16_t)port);
+    } else if (!strcmp(prot, "udp") || !strcmp(prot, "UDP")) {
+        colo_compare_passthrough_del(false, (uint16_t)port);
+    } else {
+        error_setg(errp, "COLO pass through just support tcp or udp protocol");
+        return;
+    }
 }
 
 static void netfilter_print_info(Monitor *mon, NetFilterState *nf)
-- 
2.17.1