fix asymmetric path support (still some open concerns)

2 files changed, 63 insertions, 4 deletions

diff --git a/src/cache_wt.c b/src/cache_wt.c
index 8ff8fae..65eb3fe 100644
--- a/src/cache_wt.c
+++ b/src/cache_wt.c
@@ -16,30 +16,58 @@
  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  */
 
+#include "conntrackd.h"
 #include "cache.h"
 #include "netlink.h"
 #include "us-conntrack.h"
+#include "log.h"
 
 #include <string.h>
+#include <errno.h>
 
-static void add_update(struct us_conntrack *u)
+static void add_wt(struct us_conntrack *u)
+{
+	int ret;
+	char __ct[nfct_maxsize()];
+	struct nf_conntrack *ct = (struct nf_conntrack *)(void*) __ct;
+
+	ret = nl_exist_conntrack(u->ct);
+	switch (ret) {
+	case -1:
+		dlog(LOG_ERR, "cache_wt problem: %s", strerror(errno));
+		break;
+	case 0:
+		memcpy(ct, u->ct, nfct_maxsize());
+		if (nl_create_conntrack(ct) == -1)
+			dlog(LOG_ERR, "cache_wt create: %s", strerror(errno));
+		break;
+	case 1:
+		memcpy(ct, u->ct, nfct_maxsize());
+		if (nl_update_conntrack(ct) == -1)
+			dlog(LOG_ERR, "cache_wt crt-upd: %s", strerror(errno));
+		break;
+	}
+}
+
+static void upd_wt(struct us_conntrack *u)
 {
 	char __ct[nfct_maxsize()];
 	struct nf_conntrack *ct = (struct nf_conntrack *)(void*) __ct;
 
 	memcpy(ct, u->ct, nfct_maxsize());
 
-	nl_create_conntrack(ct);
+	if (nl_update_conntrack(ct) == -1)
+		dlog(LOG_ERR, "cache_wt update:%s", strerror(errno));
 }
 
 static void writethrough_add(struct us_conntrack *u, void *data)
 {
-	add_update(u);
+	add_wt(u);
 }
 
 static void writethrough_update(struct us_conntrack *u, void *data)
 {
-	add_update(u);
+	upd_wt(u);
 }
 
 static void writethrough_destroy(struct us_conntrack *u, void *data)
diff --git a/src/netlink.c b/src/netlink.c
index f6a2378..1ab75e4 100644
--- a/src/netlink.c
+++ b/src/netlink.c
@@ -23,6 +23,8 @@
 #include "log.h"
 #include "debug.h"
 
+#include <errno.h>
+
 int ignore_conntrack(struct nf_conntrack *ct)
 {
 	/* ignore a certain protocol */
@@ -193,6 +195,17 @@ int nl_dump_conntrack_table(void)
 	return nfct_query(STATE(dump), NFCT_Q_DUMP, &CONFIG(family));
 }
 
+int nl_exist_conntrack(struct nf_conntrack *ct)
+{
+	int ret;
+
+	ret = nfct_query(STATE(dump), NFCT_Q_GET, ct);
+	if (ret == -1)
+		return errno == ENOENT ? 0 : -1;
+
+	return 1;
+}
+
 /* This function modifies the conntrack passed as argument! */
 int nl_create_conntrack(struct nf_conntrack *ct)
 {
@@ -219,6 +232,24 @@ int nl_create_conntrack(struct nf_conntrack *ct)
 	return nfct_query(STATE(dump), NFCT_Q_CREATE_UPDATE, ct);
 }
 
+/* This function modifies the conntrack passed as argument! */
+int nl_update_conntrack(struct nf_conntrack *ct)
+{
+	/* unset NAT info, otherwise we hit error */
+	nfct_attr_unset(ct, ATTR_SNAT_IPV4);
+	nfct_attr_unset(ct, ATTR_DNAT_IPV4);
+	nfct_attr_unset(ct, ATTR_SNAT_PORT);
+	nfct_attr_unset(ct, ATTR_DNAT_PORT);
+
+	if (nfct_attr_is_set(ct, ATTR_STATUS)) {
+		uint32_t status = nfct_get_attr_u32(ct, ATTR_STATUS);
+		status &= ~IPS_NAT_MASK;
+		nfct_set_attr_u32(ct, ATTR_STATUS, status);
+	}
+
+	return nl_create_conntrack(ct);
+}
+
 int nl_destroy_conntrack(struct nf_conntrack *ct)
 {
 	return nfct_query(STATE(dump), NFCT_Q_DESTROY, ct);