src: add initial ct helper support

This adds initial support for defining conntrack helper objects
which can then be assigned to connections using the objref infrastructure:

table ip filter {
  ct helper ftp-standard {
    type "ftp" protocol tcp
  }
  chain y {
	 tcp dport 21 ct helper set "ftp-standard"
  }
}

Signed-off-by: Florian Westphal <fw@strlen.de>
Acked-by: Pablo Neira Ayuso <pablo@netfilter.org>

1 files changed, 10 insertions, 0 deletions

diff --git a/src/ct.c b/src/ct.c
index 83fceff6..fd8ca87a 100644
--- a/src/ct.c
+++ b/src/ct.c
@@ -353,6 +353,16 @@ struct error_record *ct_key_parse(const struct location *loc, const char *str,
 	return error(loc, "syntax error, unexpected %s, known keys are %s", str, buf);
 }
 
+struct error_record *ct_objtype_parse(const struct location *loc, const char *str, int *type)
+{
+	if (strcmp(str, "helper") == 0) {
+		*type = NFT_OBJECT_CT_HELPER;
+		return NULL;
+	}
+
+	return error(loc, "unknown ct class '%s', want 'helper'", str);
+}
+
 struct expr *ct_expr_alloc(const struct location *loc, enum nft_ct_keys key,
 			   int8_t direction)
 {