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author | Arturo Borrero Gonzalez <arturo.borrero.glez@gmail.com> | 2013-12-26 16:38:01 +0100 |
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committer | Pablo Neira Ayuso <pablo@netfilter.org> | 2013-12-28 14:02:12 +0100 |
commit | e035b77ac7be430a5fef8c9c23f60b6b50ec81c5 (patch) | |
tree | 39b4b80d82ab6a19d394c6ac529f1765230c463b /net/netfilter/nft_meta.c | |
parent | d8bcc768c80e73cf4e948cb327949174b4b5b9e7 (diff) | |
download | op-kernel-dev-e035b77ac7be430a5fef8c9c23f60b6b50ec81c5.zip op-kernel-dev-e035b77ac7be430a5fef8c9c23f60b6b50ec81c5.tar.gz |
netfilter: nf_tables: nft_meta module get/set ops
This patch adds kernel support for the meta expression in get/set
flavour. The set operation indicates that a given packet has to be
set with a property, currently one of mark, priority, nftrace.
The get op is what was currently working: evaluate the given
packet property.
In the nftrace case, the value is always 1. Such behaviour is copied
from net/netfilter/xt_TRACE.c
The NFTA_META_DREG and NFTA_META_SREG attributes are mutually
exclusives.
Signed-off-by: Arturo Borrero Gonzalez <arturo.borrero.glez@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Diffstat (limited to 'net/netfilter/nft_meta.c')
-rw-r--r-- | net/netfilter/nft_meta.c | 146 |
1 files changed, 123 insertions, 23 deletions
diff --git a/net/netfilter/nft_meta.c b/net/netfilter/nft_meta.c index 8c28220..1ceaaa6 100644 --- a/net/netfilter/nft_meta.c +++ b/net/netfilter/nft_meta.c @@ -21,12 +21,15 @@ struct nft_meta { enum nft_meta_keys key:8; - enum nft_registers dreg:8; + union { + enum nft_registers dreg:8; + enum nft_registers sreg:8; + }; }; -static void nft_meta_eval(const struct nft_expr *expr, - struct nft_data data[NFT_REG_MAX + 1], - const struct nft_pktinfo *pkt) +static void nft_meta_get_eval(const struct nft_expr *expr, + struct nft_data data[NFT_REG_MAX + 1], + const struct nft_pktinfo *pkt) { const struct nft_meta *priv = nft_expr_priv(expr); const struct sk_buff *skb = pkt->skb; @@ -132,23 +135,50 @@ err: data[NFT_REG_VERDICT].verdict = NFT_BREAK; } +static void nft_meta_set_eval(const struct nft_expr *expr, + struct nft_data data[NFT_REG_MAX + 1], + const struct nft_pktinfo *pkt) +{ + const struct nft_meta *meta = nft_expr_priv(expr); + struct sk_buff *skb = pkt->skb; + u32 value = data[meta->sreg].data[0]; + + switch (meta->key) { + case NFT_META_MARK: + skb->mark = value; + break; + case NFT_META_PRIORITY: + skb->priority = value; + break; + case NFT_META_NFTRACE: + skb->nf_trace = 1; + break; + default: + WARN_ON(1); + } +} + static const struct nla_policy nft_meta_policy[NFTA_META_MAX + 1] = { [NFTA_META_DREG] = { .type = NLA_U32 }, [NFTA_META_KEY] = { .type = NLA_U32 }, + [NFTA_META_SREG] = { .type = NLA_U32 }, }; -static int nft_meta_init(const struct nft_ctx *ctx, const struct nft_expr *expr, - const struct nlattr * const tb[]) +static int nft_meta_init_validate_set(uint32_t key) { - struct nft_meta *priv = nft_expr_priv(expr); - int err; - - if (tb[NFTA_META_DREG] == NULL || - tb[NFTA_META_KEY] == NULL) - return -EINVAL; + switch (key) { + case NFT_META_MARK: + case NFT_META_PRIORITY: + case NFT_META_NFTRACE: + return 0; + default: + return -EOPNOTSUPP; + } +} - priv->key = ntohl(nla_get_be32(tb[NFTA_META_KEY])); - switch (priv->key) { +static int nft_meta_init_validate_get(uint32_t key) +{ + switch (key) { case NFT_META_LEN: case NFT_META_PROTOCOL: case NFT_META_PRIORITY: @@ -167,26 +197,69 @@ static int nft_meta_init(const struct nft_ctx *ctx, const struct nft_expr *expr, #ifdef CONFIG_NETWORK_SECMARK case NFT_META_SECMARK: #endif - break; + return 0; default: return -EOPNOTSUPP; } - priv->dreg = ntohl(nla_get_be32(tb[NFTA_META_DREG])); - err = nft_validate_output_register(priv->dreg); +} + +static int nft_meta_init(const struct nft_ctx *ctx, const struct nft_expr *expr, + const struct nlattr * const tb[]) +{ + struct nft_meta *priv = nft_expr_priv(expr); + int err; + + priv->key = ntohl(nla_get_be32(tb[NFTA_META_KEY])); + + if (tb[NFTA_META_DREG]) { + err = nft_meta_init_validate_get(priv->key); + if (err < 0) + return err; + + priv->dreg = ntohl(nla_get_be32(tb[NFTA_META_DREG])); + err = nft_validate_output_register(priv->dreg); + if (err < 0) + return err; + + return nft_validate_data_load(ctx, priv->dreg, NULL, + NFT_DATA_VALUE); + } + + err = nft_meta_init_validate_set(priv->key); if (err < 0) return err; - return nft_validate_data_load(ctx, priv->dreg, NULL, NFT_DATA_VALUE); + + priv->sreg = ntohl(nla_get_be32(tb[NFTA_META_SREG])); + + return 0; } -static int nft_meta_dump(struct sk_buff *skb, const struct nft_expr *expr) +static int nft_meta_get_dump(struct sk_buff *skb, + const struct nft_expr *expr) { const struct nft_meta *priv = nft_expr_priv(expr); + if (nla_put_be32(skb, NFTA_META_KEY, htonl(priv->key))) + goto nla_put_failure; if (nla_put_be32(skb, NFTA_META_DREG, htonl(priv->dreg))) goto nla_put_failure; + return 0; + +nla_put_failure: + return -1; +} + +static int nft_meta_set_dump(struct sk_buff *skb, + const struct nft_expr *expr) +{ + const struct nft_meta *priv = nft_expr_priv(expr); + if (nla_put_be32(skb, NFTA_META_KEY, htonl(priv->key))) goto nla_put_failure; + if (nla_put_be32(skb, NFTA_META_SREG, htonl(priv->sreg))) + goto nla_put_failure; + return 0; nla_put_failure: @@ -194,17 +267,44 @@ nla_put_failure: } static struct nft_expr_type nft_meta_type; -static const struct nft_expr_ops nft_meta_ops = { +static const struct nft_expr_ops nft_meta_get_ops = { .type = &nft_meta_type, .size = NFT_EXPR_SIZE(sizeof(struct nft_meta)), - .eval = nft_meta_eval, + .eval = nft_meta_get_eval, .init = nft_meta_init, - .dump = nft_meta_dump, + .dump = nft_meta_get_dump, }; +static const struct nft_expr_ops nft_meta_set_ops = { + .type = &nft_meta_type, + .size = NFT_EXPR_SIZE(sizeof(struct nft_meta)), + .eval = nft_meta_set_eval, + .init = nft_meta_init, + .dump = nft_meta_set_dump, +}; + +static const struct nft_expr_ops * +nft_meta_select_ops(const struct nft_ctx *ctx, + const struct nlattr * const tb[]) +{ + if (tb[NFTA_META_KEY] == NULL) + return ERR_PTR(-EINVAL); + + if (tb[NFTA_META_DREG] && tb[NFTA_META_SREG]) + return ERR_PTR(-EINVAL); + + if (tb[NFTA_META_DREG]) + return &nft_meta_get_ops; + + if (tb[NFTA_META_SREG]) + return &nft_meta_set_ops; + + return ERR_PTR(-EINVAL); +} + static struct nft_expr_type nft_meta_type __read_mostly = { .name = "meta", - .ops = &nft_meta_ops, + .select_ops = &nft_meta_select_ops, .policy = nft_meta_policy, .maxattr = NFTA_META_MAX, .owner = THIS_MODULE, |