Introduce skb->csum_not_inet to identify not-yet-checksummed SCTP packets.
Use this bit in combination with netdev feature bit in validate_xmit_skb,
to discriminate whether skb needs crc32c or 2-complement Internet Checksum
(or none of the two, when the underlying device can do checksum offload).
Signed-off-by: Davide Caratti <dcara...@redhat.com>
---
include/linux/skbuff.h | 1 +
net/core/dev.c | 14 ++++++++++++--
net/netfilter/ipvs/ip_vs_proto_sctp.c | 1 +
net/netfilter/nf_nat_proto_sctp.c | 1 +
net/sched/act_csum.c | 1 +
net/sctp/output.c | 1 +
6 files changed, 17 insertions(+), 2 deletions(-)
diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
index 0671131..236b7d9 100644
--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -759,6 +759,7 @@ struct sk_buff {
__u8 tc_redirected:1;
__u8 tc_from_ingress:1;
#endif
+ __u8 csum_not_inet:1;
#ifdef CONFIG_NET_SCHED
__u16 tc_index; /* traffic control index */
diff --git a/net/core/dev.c b/net/core/dev.c
index b9fb843..fae3217 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -2614,6 +2614,7 @@ int skb_sctp_csum_help(struct sk_buff *skb)
}
*(__le32 *)(skb->data + offset) = crc32c_csum;
skb->ip_summed = CHECKSUM_NONE;
+ skb->csum_not_inet = 0;
out:
return ret;
}
@@ -2960,6 +2961,16 @@ static struct sk_buff *validate_xmit_vlan(struct sk_buff
*skb,
return skb;
}
+static int skb_csum_hwoffload_help(struct sk_buff *skb,
+ netdev_features_t features)
+{
+ if (unlikely(skb->csum_not_inet))
+ return !(features & NETIF_F_SCTP_CRC) ?
+ skb_sctp_csum_help(skb) : 0;
+
+ return !(features & NETIF_F_CSUM_MASK) ? skb_checksum_help(skb) : 0;
+}
+
static struct sk_buff *validate_xmit_skb(struct sk_buff *skb, struct
net_device *dev)
{
netdev_features_t features;
@@ -2995,8 +3006,7 @@ static struct sk_buff *validate_xmit_skb(struct sk_buff
*skb, struct net_device
else
skb_set_transport_header(skb,
skb_checksum_start_offset(skb));
- if (!(features & NETIF_F_CSUM_MASK) &&
- skb_checksum_help(skb))
+ if (skb_csum_hwoffload_help(skb, features))
goto out_kfree_skb;
}
}
diff --git a/net/netfilter/ipvs/ip_vs_proto_sctp.c
b/net/netfilter/ipvs/ip_vs_proto_sctp.c
index d952d67..4972a60 100644
--- a/net/netfilter/ipvs/ip_vs_proto_sctp.c
+++ b/net/netfilter/ipvs/ip_vs_proto_sctp.c
@@ -81,6 +81,7 @@ static void sctp_nat_csum(struct sk_buff *skb, sctp_sctphdr_t
*sctph,
unsigned int sctphoff)
{
sctph->checksum = sctp_compute_cksum(skb, sctphoff);
+ skb->csum_not_inet = 0;
skb->ip_summed = CHECKSUM_UNNECESSARY;
}
diff --git a/net/netfilter/nf_nat_proto_sctp.c
b/net/netfilter/nf_nat_proto_sctp.c
index 31d3586..9459b88 100644
--- a/net/netfilter/nf_nat_proto_sctp.c
+++ b/net/netfilter/nf_nat_proto_sctp.c
@@ -49,6 +49,7 @@ sctp_manip_pkt(struct sk_buff *skb,
if (skb->ip_summed != CHECKSUM_PARTIAL) {
hdr->checksum = sctp_compute_cksum(skb, hdroff);
+ skb->csum_not_inet = 0;
skb->ip_summed = CHECKSUM_NONE;
}
diff --git a/net/sched/act_csum.c b/net/sched/act_csum.c
index e978ccd4..85cb150 100644
--- a/net/sched/act_csum.c
+++ b/net/sched/act_csum.c
@@ -337,6 +337,7 @@ static int tcf_csum_sctp(struct sk_buff *skb, unsigned int
ihl,
sctph->checksum = sctp_compute_cksum(skb,
skb_network_offset(skb) + ihl);
+ skb->csum_not_inet = 0;
skb->ip_summed = CHECKSUM_NONE;
return 1;
diff --git a/net/sctp/output.c b/net/sctp/output.c
index 814eac0..0dc227b 100644
--- a/net/sctp/output.c
+++ b/net/sctp/output.c
@@ -528,6 +528,7 @@ static int sctp_packet_pack(struct sctp_packet *packet,
} else {
chksum:
head->ip_summed = CHECKSUM_PARTIAL;
+ head->csum_not_inet = 1;
head->csum_start = skb_transport_header(head) - head->head;
head->csum_offset = offsetof(struct sctphdr, checksum);
}
--
2.7.4
