| Message ID | 1366126328-25874-5-git-send-email-fw@strlen.de |
|---|---|
| State | Superseded |
| Headers | show |
On Tue, 2013-04-16 at 17:32 +0200, Florian Westphal wrote: > 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. > > Cc: Eric Dumazet <eric.dumazet@gmail.com> > Signed-off-by: Florian Westphal <fw@strlen.de> > --- > > +static int nfqnl_put_packet_info(struct sk_buff *nlskb, struct sk_buff *packet) > +{ > + __u32 flags = 0; > + > + if (skb_is_gso(packet)) > + flags = NFQA_SKB_GSO; > + if (packet->ip_summed == CHECKSUM_PARTIAL) > + flags |= NFQA_SKB_CSUMNOTREADY; > + > + return nla_put_be32(nlskb, NFQA_SKB_INFO, htonl(flags)); Maybe you could avoid sending NFQA_SKB_INFO if flags == 0 ? -- To unsubscribe from this list: send the line "unsubscribe netfilter-devel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Eric Dumazet <eric.dumazet@gmail.com> wrote: > On Tue, 2013-04-16 at 17:32 +0200, Florian Westphal wrote: > > 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. [..] > > +static int nfqnl_put_packet_info(struct sk_buff *nlskb, struct sk_buff *packet) > > +{ > > + __u32 flags = 0; > > + > > + if (skb_is_gso(packet)) > > + flags = NFQA_SKB_GSO; > > > + if (packet->ip_summed == CHECKSUM_PARTIAL) > > + flags |= NFQA_SKB_CSUMNOTREADY; > > + > > + return nla_put_be32(nlskb, NFQA_SKB_INFO, htonl(flags)); > > Maybe you could avoid sending NFQA_SKB_INFO if flags == 0 ? Sure, will change it in the next round. -- To unsubscribe from this list: send the line "unsubscribe netfilter-devel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
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 8ccaece..839c65b 100644 --- a/net/netfilter/nfnetlink_queue_core.c +++ b/net/netfilter/nfnetlink_queue_core.c @@ -275,6 +275,18 @@ 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 (skb_is_gso(packet)) + flags = NFQA_SKB_GSO; + if (packet->ip_summed == CHECKSUM_PARTIAL) + flags |= NFQA_SKB_CSUMNOTREADY; + + return nla_put_be32(nlskb, NFQA_SKB_INFO, htonl(flags)); +} + static struct sk_buff * nfqnl_build_packet_message(struct nfqnl_instance *queue, struct nf_queue_entry *entry, @@ -304,6 +316,7 @@ 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) @@ -456,6 +469,9 @@ 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;
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. Cc: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: Florian Westphal <fw@strlen.de> --- include/uapi/linux/netfilter/nfnetlink_queue.h | 7 +++++++ net/netfilter/nfnetlink_queue_core.c | 16 ++++++++++++++++ 2 files changed, 23 insertions(+), 0 deletions(-)