datapath: conntrack NF_NAT_RANGE_PROTO_RANDOM_FULLY compat code.

Linux kernel 3.13 and older do not have
NF_NAT_RANGE_PROTO_RANDOM_FULLY (unless backported by the
distribution).  Silently fall back to NF_NAT_RANGE_PROTO_RANDOM to
maintain OVS API compatibility.

Signed-off-by: Jarno Rajahalme <jarno@ovn.org>
Acked-by: Jesse Gross <jesse@kernel.org>

diff --git a/datapath/conntrack.c b/datapath/conntrack.c
index df60fa5..7d7982b 100644 (file)
--- a/datapath/conntrack.c
+++ b/datapath/conntrack.c
@@ -71,6 +71,7 @@ struct ovs_conntrack_info {
        struct nf_conn *ct;
        u8 commit : 1;
        u8 nat : 3;                 /* enum ovs_ct_nat */
+       u8 random_fully_compat : 1; /* bool */
        u16 family;
        struct md_mark mark;
        struct md_labels labels;
@@ -1048,7 +1049,12 @@ static int parse_nat(const struct nlattr *attr,
                        break;
 
                case OVS_NAT_ATTR_PROTO_RANDOM:
+#ifdef NF_NAT_RANGE_PROTO_RANDOM_FULLY
                        info->range.flags |= NF_NAT_RANGE_PROTO_RANDOM_FULLY;
+#else
+                       info->range.flags |= NF_NAT_RANGE_PROTO_RANDOM;
+                       info->random_fully_compat = true;
+#endif
                        break;
 
                default:
@@ -1322,11 +1328,15 @@ static bool ovs_ct_nat_to_attr(const struct ovs_conntrack_info *info,
            nla_put_flag(skb, OVS_NAT_ATTR_PERSISTENT))
                return false;
        if (info->range.flags & NF_NAT_RANGE_PROTO_RANDOM &&
-           nla_put_flag(skb, OVS_NAT_ATTR_PROTO_HASH))
+           nla_put_flag(skb, info->random_fully_compat
+                        ? OVS_NAT_ATTR_PROTO_RANDOM
+                        : OVS_NAT_ATTR_PROTO_HASH))
                return false;
+#ifdef NF_NAT_RANGE_PROTO_RANDOM_FULLY
        if (info->range.flags & NF_NAT_RANGE_PROTO_RANDOM_FULLY &&
            nla_put_flag(skb, OVS_NAT_ATTR_PROTO_RANDOM))
                return false;
+#endif
 out:
        nla_nest_end(skb, start);