diff options
| author | Florian Westphal <fw@strlen.de> | 2013-04-19 04:58:26 (GMT) |
|---|---|---|
| committer | Pablo Neira Ayuso <pablo@netfilter.org> | 2013-04-29 18:09:06 (GMT) |
| commit | 7237190df8c4129241697530a4eecabdc4ecc66e (patch) | |
| tree | ef91e17a9510d81f721f7870e5141403fc2ad503 | |
| parent | a5fedd43d5f6c94c71053a66e4c3d2e35f1731a2 (diff) | |
| download | linux-7237190df8c4129241697530a4eecabdc4ecc66e.tar.xz | |
netfilter: nfnetlink_queue: add skb info attribute
Once we allow userspace to receive gso/gro packets, userspace
needs to be able to determine when checksums appear to be
broken, but are not.
NFQA_SKB_CSUMNOTREADY means 'checksums will be fixed in kernel
later, pretend they are ok'.
NFQA_SKB_GSO could be used for statistics, or to determine when
packet size exceeds mtu.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
| -rw-r--r-- | include/uapi/linux/netfilter/nfnetlink_queue.h | 7 | ||||
| -rw-r--r-- | net/netfilter/nfnetlink_queue_core.c | 16 |
2 files changed, 23 insertions, 0 deletions
diff --git a/include/uapi/linux/netfilter/nfnetlink_queue.h b/include/uapi/linux/netfilter/nfnetlink_queue.h index 70ec8c2..0069da3 100644 --- a/include/uapi/linux/netfilter/nfnetlink_queue.h +++ b/include/uapi/linux/netfilter/nfnetlink_queue.h @@ -45,6 +45,7 @@ enum nfqnl_attr_type { NFQA_CT, /* nf_conntrack_netlink.h */ NFQA_CT_INFO, /* enum ip_conntrack_info */ NFQA_CAP_LEN, /* __u32 length of captured packet */ + NFQA_SKB_INFO, /* __u32 skb meta information */ __NFQA_MAX }; @@ -98,4 +99,10 @@ enum nfqnl_attr_config { #define NFQA_CFG_F_CONNTRACK (1 << 1) #define NFQA_CFG_F_MAX (1 << 2) +/* flags for NFQA_SKB_INFO */ +/* packet appears to have wrong checksums, but they are ok */ +#define NFQA_SKB_CSUMNOTREADY (1 << 0) +/* packet is GSO (i.e., exceeds device mtu) */ +#define NFQA_SKB_GSO (1 << 1) + #endif /* _NFNETLINK_QUEUE_H */ diff --git a/net/netfilter/nfnetlink_queue_core.c b/net/netfilter/nfnetlink_queue_core.c index edbae4c..d052cd6 100644 --- a/net/netfilter/nfnetlink_queue_core.c +++ b/net/netfilter/nfnetlink_queue_core.c @@ -272,6 +272,18 @@ nfqnl_zcopy(struct sk_buff *to, const struct sk_buff *from, int len, int hlen) skb_shinfo(to)->nr_frags = j; } +static int nfqnl_put_packet_info(struct sk_buff *nlskb, struct sk_buff *packet) +{ + __u32 flags = 0; + + if (packet->ip_summed == CHECKSUM_PARTIAL) + flags = NFQA_SKB_CSUMNOTREADY; + if (skb_is_gso(packet)) + flags |= NFQA_SKB_GSO; + + return flags ? nla_put_be32(nlskb, NFQA_SKB_INFO, htonl(flags)) : 0; +} + static struct sk_buff * nfqnl_build_packet_message(struct nfqnl_instance *queue, struct nf_queue_entry *entry, @@ -301,6 +313,7 @@ nfqnl_build_packet_message(struct nfqnl_instance *queue, #endif + nla_total_size(sizeof(u_int32_t)) /* mark */ + nla_total_size(sizeof(struct nfqnl_msg_packet_hw)) + + nla_total_size(sizeof(u_int32_t)) /* skbinfo */ + nla_total_size(sizeof(u_int32_t)); /* cap_len */ if (entskb->tstamp.tv64) @@ -454,6 +467,9 @@ nfqnl_build_packet_message(struct nfqnl_instance *queue, if (cap_len > 0 && nla_put_be32(skb, NFQA_CAP_LEN, htonl(cap_len))) goto nla_put_failure; + if (nfqnl_put_packet_info(skb, entskb)) + goto nla_put_failure; + if (data_len) { struct nlattr *nla; |