nft: split gen_payload() to allocate register and initialize expression

Add __gen_payload(), in preparation for the dynamic register allocation.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

diff --git a/iptables/nft.c b/iptables/nft.c
index bdfef0244b38eb9f27dbb2c81a3bb7ef45f90882..07653ee1a3d6baa29011e2e4fa4c740ea9b85c40 100644 (file)
--- a/iptables/nft.c
+++ b/iptables/nft.c
@@ -1090,20 +1090,30 @@ static struct nftnl_set *add_anon_set(struct nft_handle *h, const char *table,
 }
 
 static struct nftnl_expr *
-gen_payload(struct nft_handle *h, uint32_t base, uint32_t offset, uint32_t len,
-           uint8_t *dreg)
+__gen_payload(uint32_t base, uint32_t offset, uint32_t len, uint8_t reg)
 {
        struct nftnl_expr *e = nftnl_expr_alloc("payload");
-       uint8_t reg;
 
        if (!e)
                return NULL;
 
-       reg = NFT_REG_1;
        nftnl_expr_set_u32(e, NFTNL_EXPR_PAYLOAD_BASE, base);
        nftnl_expr_set_u32(e, NFTNL_EXPR_PAYLOAD_OFFSET, offset);
        nftnl_expr_set_u32(e, NFTNL_EXPR_PAYLOAD_LEN, len);
        nftnl_expr_set_u32(e, NFTNL_EXPR_PAYLOAD_DREG, reg);
+
+       return e;
+}
+
+static struct nftnl_expr *
+gen_payload(struct nft_handle *h, uint32_t base, uint32_t offset, uint32_t len,
+           uint8_t *dreg)
+{
+       struct nftnl_expr *e;
+       uint8_t reg;
+
+       reg = NFT_REG_1;
+       e = __gen_payload(base, offset, len, reg);
        *dreg = reg;
 
        return e;