expr: nat: add nft_str2nat function

Add function that will be use in the JSON parser.

Signed-off-by: Alvaro Neira Ayuso Ayuso <alvaroneay@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

diff --git a/src/expr/nat.c b/src/expr/nat.c
index 654d4d74fbdb92077382cabb393f2f4cd6ffb26c..c81dc7f4e8b89aee9cbf56fbdb3375005eb21a8c 100644 (file)
--- a/src/expr/nat.c
+++ b/src/expr/nat.c
@@ -15,6 +15,7 @@
 #include <stdio.h>
 #include <stdint.h>
 #include <limits.h>
+#include <string.h>
 #include <errno.h>
 #include <arpa/inet.h>
 #include <libmnl/libmnl.h>
@@ -183,6 +184,17 @@ nft_rule_expr_nat_build(struct nlmsghdr *nlh, struct nft_rule_expr *e)
                                 htonl(nat->sreg_proto_max));
 }
 
+static inline int nft_str2nat(const char *nat)
+{
+       if (strcmp(nat, "snat") == 0)
+               return NFT_NAT_SNAT;
+       else if (strcmp(nat, "dnat") == 0)
+               return NFT_NAT_DNAT;
+       else {
+               errno = EINVAL;
+               return -1;
+       }
+}
 
 static int nft_rule_expr_nat_xml_parse(struct nft_rule_expr *e, mxml_node_t *tree)
 {
@@ -190,19 +202,17 @@ static int nft_rule_expr_nat_xml_parse(struct nft_rule_expr *e, mxml_node_t *tre
        struct nft_expr_nat *nat = nft_expr_data(e);
        const char *nat_type;
        int32_t reg;
-       int family;
+       int family, nat_type_value;
 
        nat_type = nft_mxml_str_parse(tree, "nat_type", MXML_DESCEND_FIRST);
        if (nat_type == NULL)
                return -1;
 
-       if (strcmp(nat_type, "snat") == 0) {
-               nat->type = NFT_NAT_SNAT;
-       } else if (strcmp(nat_type, "dnat") == 0) {
-               nat->type = NFT_NAT_DNAT;
-       } else
-               goto err;
+       nat_type_value = nft_str2nat(nat_type);
+       if (nat_type_value < 0)
+               return -1;
 
+       nat->type = nat_type_value;
        e->flags |= (1 << NFT_EXPR_NAT_TYPE);
 
        family = nft_mxml_family_parse(tree, "family", MXML_DESCEND_FIRST);
@@ -243,9 +253,6 @@ static int nft_rule_expr_nat_xml_parse(struct nft_rule_expr *e, mxml_node_t *tre
        e->flags |= (1 << NFT_EXPR_NAT_REG_PROTO_MAX);
 
        return 0;
-err:
-       errno = EINVAL;
-       return -1;
 #else
        errno = EOPNOTSUPP;
        return -1;