[PATCH net-next v5 2/3] net/xfrm: Add inner_ipproto into sec_path
From: Huy Nguyen <hidden>
Date: 2021-06-14 14:34:08
Subsystem:
networking [general], networking [ipsec], the rest · Maintainers:
"David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Steffen Klassert, Herbert Xu, Linus Torvalds
The inner_ipproto saves the inner IP protocol of the plain text packet. This allows vendor's IPsec feature making offload decision at skb's features_check and configuring hardware at ndo_start_xmit. For example, ConnectX6-DX IPsec device needs the plaintext's IP protocol to support partial checksum offload on VXLAN/GENEVE packet over IPsec transport mode tunnel. Signed-off-by: Raed Salem <redacted> Signed-off-by: Huy Nguyen <redacted> Cc: Steffen Klassert <steffen.klassert@secunet.com> --- include/net/xfrm.h | 1 + net/xfrm/xfrm_output.c | 41 ++++++++++++++++++++++++++++++++++++++++- 2 files changed, 41 insertions(+), 1 deletion(-)
diff --git a/include/net/xfrm.h b/include/net/xfrm.h
index c8890da00b8a..30e94d98005b 100644
--- a/include/net/xfrm.h
+++ b/include/net/xfrm.h@@ -1022,6 +1022,7 @@ struct xfrm_offload { #define CRYPTO_INVALID_PROTOCOL 128 __u8 proto; + __u8 inner_ipproto; }; struct sec_path {
diff --git a/net/xfrm/xfrm_output.c b/net/xfrm/xfrm_output.c
index e14fca1fb003..1eac2c8565ed 100644
--- a/net/xfrm/xfrm_output.c
+++ b/net/xfrm/xfrm_output.c@@ -640,6 +640,42 @@ static int xfrm_output_gso(struct net *net, struct sock *sk, struct sk_buff *skb return 0; } +/* For partial checksum offload, the outer header checksum is calculated + * by software and the inner header checksum is calculated by hardware. + * This requires hardware to know the inner packet type to calculate + * the inner header checksum. Save inner ip protocol here to avoid + * traversing the packet in the vendor's xmit code. + * If the encap type is IPIP, just save skb->inner_ipproto. Otherwise, + * get the ip protocol from the IP header. + */ +static void xfrm_get_inner_ipproto(struct sk_buff *skb) +{ + struct xfrm_offload *xo = xfrm_offload(skb); + const struct ethhdr *eth; + + if (!xo) + return; + + if (skb->inner_protocol_type == ENCAP_TYPE_IPPROTO) { + xo->inner_ipproto = skb->inner_ipproto; + return; + } + + if (skb->inner_protocol_type != ENCAP_TYPE_ETHER) + return; + + eth = (struct ethhdr *)skb_inner_mac_header(skb); + + switch (ntohs(eth->h_proto)) { + case ETH_P_IPV6: + xo->inner_ipproto = inner_ipv6_hdr(skb)->nexthdr; + break; + case ETH_P_IP: + xo->inner_ipproto = inner_ip_hdr(skb)->protocol; + break; + } +} + int xfrm_output(struct sock *sk, struct sk_buff *skb) { struct net *net = dev_net(skb_dst(skb)->dev);
@@ -669,12 +705,15 @@ int xfrm_output(struct sock *sk, struct sk_buff *skb) kfree_skb(skb); return -ENOMEM; } - skb->encapsulation = 1; sp->olen++; sp->xvec[sp->len++] = x; xfrm_state_hold(x); + if (skb->encapsulation) + xfrm_get_inner_ipproto(skb); + skb->encapsulation = 1; + if (skb_is_gso(skb)) { if (skb->inner_protocol) return xfrm_output_gso(net, sk, skb);
--
2.24.1