netfilter: xt_CT: add alias flag

This patch adds the alias flag to support full NOTRACK target
aliasing.

Based on initial patch from Jozsef Kadlecsik.

Acked-by: Jozsef Kadlecsik <kadlec@blackhole.kfki.hi>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

1 files changed, 29 insertions, 3 deletions

diff --git a/net/netfilter/xt_CT.c b/net/netfilter/xt_CT.c
index d69f1c7532f7..a60261cb0e80 100644
--- a/net/netfilter/xt_CT.c
+++ b/net/netfilter/xt_CT.c
@@ -185,9 +185,6 @@ static int xt_ct_tg_check(const struct xt_tgchk_param *par,
         struct nf_conn *ct;
         int ret = -EOPNOTSUPP;
 
-        if (info->flags & ~XT_CT_NOTRACK)
-                return -EINVAL;
-
         if (info->flags & XT_CT_NOTRACK) {
                 ct = nf_ct_untracked_get();
                 atomic_inc(&ct->ct_general.use);
@@ -256,6 +253,9 @@ static int xt_ct_tg_check_v0(const struct xt_tgchk_param *par)
         };
         int ret;
 
+        if (info->flags & ~XT_CT_NOTRACK)
+                return -EINVAL;
+
         memcpy(info_v1.helper, info->helper, sizeof(info->helper));
 
         ret = xt_ct_tg_check(par, &info_v1);
@@ -269,6 +269,21 @@ static int xt_ct_tg_check_v0(const struct xt_tgchk_param *par)
 
 static int xt_ct_tg_check_v1(const struct xt_tgchk_param *par)
 {
+        struct xt_ct_target_info_v1 *info = par->targinfo;
+
+        if (info->flags & ~XT_CT_NOTRACK)
+                return -EINVAL;
+
+        return xt_ct_tg_check(par, par->targinfo);
+}
+
+static int xt_ct_tg_check_v2(const struct xt_tgchk_param *par)
+{
+        struct xt_ct_target_info_v1 *info = par->targinfo;
+
+        if (info->flags & ~XT_CT_MASK)
+                return -EINVAL;
+
         return xt_ct_tg_check(par, par->targinfo);
 }
 
@@ -350,6 +365,17 @@ static struct xt_target xt_ct_tg_reg[] __read_mostly = {
                 .table          = "raw",
                 .me             = THIS_MODULE,
         },
+        {
+                .name           = "CT",
+                .family         = NFPROTO_UNSPEC,
+                .revision       = 2,
+                .targetsize     = sizeof(struct xt_ct_target_info_v1),
+                .checkentry     = xt_ct_tg_check_v2,
+                .destroy        = xt_ct_tg_destroy_v1,
+                .target         = xt_ct_target_v1,
+                .table          = "raw",
+                .me             = THIS_MODULE,
+        },
 };
 
 static unsigned int