introduce skb_csum_hwoffload_help and use it as a replacement for
skb_checksum_help in validate_xmit_skb, to compute checksum using crc32c or
2-complement Internet Checksum (or leave the packet unchanged and let the
NIC do the checksum), depending on netdev checksum offloading capabilities
and on presence of IPPROTO_SCTP as protocol number in IPv4/IPv6 header.
Reviewed-by: Marcelo Ricardo Leitner <marcelo.leit...@gmail.com>
Signed-off-by: Davide Caratti <dcara...@redhat.com>
---
net/core/dev.c | 52 ++++++++++++++++++++++++++++++++++++++++++++++++++--
1 file changed, 50 insertions(+), 2 deletions(-)
diff --git a/net/core/dev.c b/net/core/dev.c
index 45cee84..f8cb3ba 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -140,6 +140,7 @@
#include <linux/hrtimer.h>
#include <linux/netfilter_ingress.h>
#include <linux/crash_dump.h>
+#include <linux/sctp.h>
#include "net-sysfs.h"
@@ -2960,6 +2961,54 @@ 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)
+{
+ bool encap = skb->encapsulation;
+ unsigned int offset = 0;
+ __be16 protocol;
+
+ if (likely((features & (NETIF_F_SCTP_CRC | NETIF_F_CSUM_MASK)) ==
+ (NETIF_F_SCTP_CRC | NETIF_F_CSUM_MASK)))
+ return 0;
+
+ if (skb->csum_offset != offsetof(struct sctphdr, checksum))
+ goto inet_csum;
+
+ if (encap) {
+ protocol = skb->inner_protocol;
+ if (skb->inner_protocol_type == ENCAP_TYPE_IPPROTO)
+ switch (protocol) {
+ case IPPROTO_IPV6:
+ protocol = ntohs(ETH_P_IPV6);
+ break;
+ case IPPROTO_IP:
+ protocol = ntohs(ETH_P_IP);
+ break;
+ default:
+ goto inet_csum;
+ }
+ } else {
+ protocol = vlan_get_protocol(skb);
+ }
+ switch (protocol) {
+ case ntohs(ETH_P_IP):
+ if ((encap ? inner_ip_hdr(skb) : ip_hdr(skb))->protocol ==
+ IPPROTO_SCTP)
+ goto sctp_csum;
+ break;
+ case ntohs(ETH_P_IPV6):
+ if (ipv6_find_hdr(skb, &offset, IPPROTO_SCTP, NULL, NULL) ==
+ IPPROTO_SCTP)
+ goto sctp_csum;
+ break;
+ }
+inet_csum:
+ return !(features & NETIF_F_CSUM_MASK) ? skb_checksum_help(skb) : 0;
+sctp_csum:
+ return !(features & NETIF_F_SCTP_CRC) ? skb_sctp_csum_help(skb) : 0;
+}
+
static struct sk_buff *validate_xmit_skb(struct sk_buff *skb, struct
net_device *dev)
{
netdev_features_t features;
@@ -2995,8 +3044,7 @@ 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;
}
}
--
2.7.4
