diff options
| author | Florian Westphal <fw@strlen.de> | 2015-12-10 18:04:07 +0100 |
|---|---|---|
| committer | Pablo Neira Ayuso <pablo@netfilter.org> | 2015-12-18 14:12:56 +0100 |
| commit | b4aae759c22e71a3c32144f0b3bc4f2fa4aaae98 (patch) | |
| tree | b45a5994f419f696c3dbd3bde26a74a1ee7845e6 /net/netfilter | |
| parent | 9c55d3b5459bffe8ac098175e672a90260c0cfa4 (diff) | |
netfilter: meta: add support for setting skb->pkttype
This allows to redirect bridged packets to local machine:
ether type ip ether daddr set aa:53:08:12:34:56 meta pkttype set unicast
Without 'set unicast', ip stack discards PACKET_OTHERHOST skbs.
It is also useful to add support for a '-m cluster like' nft rule
(where switch floods packets to several nodes, and each cluster node
node processes a subset of packets for load distribution).
Mangling is restricted to HOST/OTHER/BROAD/MULTICAST, i.e. you cannot set
skb->pkt_type to PACKET_KERNEL or change PACKET_LOOPBACK to PACKET_HOST.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Diffstat (limited to 'net/netfilter')
| -rw-r--r-- | net/netfilter/nft_meta.c | 38 |
1 files changed, 38 insertions, 0 deletions
diff --git a/net/netfilter/nft_meta.c b/net/netfilter/nft_meta.c index 5bcd1b0cc2ec..fe885bf271c5 100644 --- a/net/netfilter/nft_meta.c +++ b/net/netfilter/nft_meta.c @@ -26,6 +26,8 @@ #include <net/netfilter/nf_tables_core.h> #include <net/netfilter/nft_meta.h> +#include <uapi/linux/netfilter_bridge.h> /* NF_BR_PRE_ROUTING */ + void nft_meta_get_eval(const struct nft_expr *expr, struct nft_regs *regs, const struct nft_pktinfo *pkt) @@ -190,6 +192,13 @@ err: } EXPORT_SYMBOL_GPL(nft_meta_get_eval); +/* don't change or set _LOOPBACK, _USER, etc. */ +static bool pkt_type_ok(u32 p) +{ + return p == PACKET_HOST || p == PACKET_BROADCAST || + p == PACKET_MULTICAST || p == PACKET_OTHERHOST; +} + void nft_meta_set_eval(const struct nft_expr *expr, struct nft_regs *regs, const struct nft_pktinfo *pkt) @@ -205,6 +214,11 @@ void nft_meta_set_eval(const struct nft_expr *expr, case NFT_META_PRIORITY: skb->priority = value; break; + case NFT_META_PKTTYPE: + if (skb->pkt_type != value && + pkt_type_ok(value) && pkt_type_ok(skb->pkt_type)) + skb->pkt_type = value; + break; case NFT_META_NFTRACE: skb->nf_trace = 1; break; @@ -273,6 +287,24 @@ int nft_meta_get_init(const struct nft_ctx *ctx, } EXPORT_SYMBOL_GPL(nft_meta_get_init); +static int nft_meta_set_init_pkttype(const struct nft_ctx *ctx) +{ + unsigned int hooks; + + switch (ctx->afi->family) { + case NFPROTO_BRIDGE: + hooks = 1 << NF_BR_PRE_ROUTING; + break; + case NFPROTO_NETDEV: + hooks = 1 << NF_NETDEV_INGRESS; + break; + default: + return -EOPNOTSUPP; + } + + return nft_chain_validate_hooks(ctx->chain, hooks); +} + int nft_meta_set_init(const struct nft_ctx *ctx, const struct nft_expr *expr, const struct nlattr * const tb[]) @@ -290,6 +322,12 @@ int nft_meta_set_init(const struct nft_ctx *ctx, case NFT_META_NFTRACE: len = sizeof(u8); break; + case NFT_META_PKTTYPE: + err = nft_meta_set_init_pkttype(ctx); + if (err) + return err; + len = sizeof(u8); + break; default: return -EOPNOTSUPP; } |