netfilter: nft_ct: split nft_ct_init() into two functions for get/set

For value spanning multiple registers, we need to validate the length
of data loads. In order to add this to nft_ct, we need the length from
key validation. Split the nft_ct_init() function into two functions
for the get and set operations as preparation for that.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

diff --git a/net/netfilter/nft_ct.c b/net/netfilter/nft_ct.c
index a2c45bd8691c405fa0f12cff496344f5a3bbf7d6..cc5603016242ea8e1f5cdce1d633e3a2687276ae 100644 (file)
--- a/net/netfilter/nft_ct.c
+++ b/net/netfilter/nft_ct.c
@@ -215,22 +215,14 @@ static void nft_ct_l3proto_module_put(uint8_t family)
                nf_ct_l3proto_module_put(family);
 }
 
-static int nft_ct_init_validate_get(const struct nft_expr *expr,
-                                   const struct nlattr * const tb[])
+static int nft_ct_get_init(const struct nft_ctx *ctx,
+                          const struct nft_expr *expr,
+                          const struct nlattr * const tb[])
 {
        struct nft_ct *priv = nft_expr_priv(expr);
+       int err;
 
-       if (tb[NFTA_CT_DIRECTION] != NULL) {
-               priv->dir = nla_get_u8(tb[NFTA_CT_DIRECTION]);
-               switch (priv->dir) {
-               case IP_CT_DIR_ORIGINAL:
-               case IP_CT_DIR_REPLY:
-                       break;
-               default:
-                       return -EINVAL;
-               }
-       }
-
+       priv->key = ntohl(nla_get_be32(tb[NFTA_CT_KEY]));
        switch (priv->key) {
        case NFT_CT_STATE:
        case NFT_CT_DIRECTION:
@@ -262,12 +254,42 @@ static int nft_ct_init_validate_get(const struct nft_expr *expr,
                return -EOPNOTSUPP;
        }
 
+       if (tb[NFTA_CT_DIRECTION] != NULL) {
+               priv->dir = nla_get_u8(tb[NFTA_CT_DIRECTION]);
+               switch (priv->dir) {
+               case IP_CT_DIR_ORIGINAL:
+               case IP_CT_DIR_REPLY:
+                       break;
+               default:
+                       return -EINVAL;
+               }
+       }
+
+       priv->dreg = ntohl(nla_get_be32(tb[NFTA_CT_DREG]));
+       err = nft_validate_output_register(priv->dreg);
+       if (err < 0)
+               return err;
+
+       err = nft_validate_data_load(ctx, priv->dreg, NULL, NFT_DATA_VALUE);
+       if (err < 0)
+               return err;
+
+       err = nft_ct_l3proto_try_module_get(ctx->afi->family);
+       if (err < 0)
+               return err;
+
        return 0;
 }
 
-static int nft_ct_init_validate_set(uint32_t key)
+static int nft_ct_set_init(const struct nft_ctx *ctx,
+                          const struct nft_expr *expr,
+                          const struct nlattr * const tb[])
 {
-       switch (key) {
+       struct nft_ct *priv = nft_expr_priv(expr);
+       int err;
+
+       priv->key = ntohl(nla_get_be32(tb[NFTA_CT_KEY]));
+       switch (priv->key) {
 #ifdef CONFIG_NF_CONNTRACK_MARK
        case NFT_CT_MARK:
                break;
@@ -276,42 +298,10 @@ static int nft_ct_init_validate_set(uint32_t key)
                return -EOPNOTSUPP;
        }
 
-       return 0;
-}
-
-static int nft_ct_init(const struct nft_ctx *ctx,
-                      const struct nft_expr *expr,
-                      const struct nlattr * const tb[])
-{
-       struct nft_ct *priv = nft_expr_priv(expr);
-       int err;
-
-       priv->key = ntohl(nla_get_be32(tb[NFTA_CT_KEY]));
-
-       if (tb[NFTA_CT_DREG]) {
-               err = nft_ct_init_validate_get(expr, tb);
-               if (err < 0)
-                       return err;
-
-               priv->dreg = ntohl(nla_get_be32(tb[NFTA_CT_DREG]));
-               err = nft_validate_output_register(priv->dreg);
-               if (err < 0)
-                       return err;
-
-               err = nft_validate_data_load(ctx, priv->dreg, NULL,
-                                            NFT_DATA_VALUE);
-               if (err < 0)
-                       return err;
-       } else {
-               err = nft_ct_init_validate_set(priv->key);
-               if (err < 0)
-                       return err;
-
-               priv->sreg = ntohl(nla_get_be32(tb[NFTA_CT_SREG]));
-               err = nft_validate_input_register(priv->sreg);
-               if (err < 0)
-                       return err;
-       }
+       priv->sreg = ntohl(nla_get_be32(tb[NFTA_CT_SREG]));
+       err = nft_validate_input_register(priv->sreg);
+       if (err < 0)
+               return err;
 
        err = nft_ct_l3proto_try_module_get(ctx->afi->family);
        if (err < 0)
@@ -372,7 +362,7 @@ static const struct nft_expr_ops nft_ct_get_ops = {
        .type           = &nft_ct_type,
        .size           = NFT_EXPR_SIZE(sizeof(struct nft_ct)),
        .eval           = nft_ct_get_eval,
-       .init           = nft_ct_init,
+       .init           = nft_ct_get_init,
        .destroy        = nft_ct_destroy,
        .dump           = nft_ct_get_dump,
 };
@@ -381,7 +371,7 @@ static const struct nft_expr_ops nft_ct_set_ops = {
        .type           = &nft_ct_type,
        .size           = NFT_EXPR_SIZE(sizeof(struct nft_ct)),
        .eval           = nft_ct_set_eval,
-       .init           = nft_ct_init,
+       .init           = nft_ct_set_init,
        .destroy        = nft_ct_destroy,
        .dump           = nft_ct_set_dump,
 };