> 2021年3月4日 下午10:02，Willem de Bruijn <willemdebruijn.kernel@xxxxxxxxx> 写道：
>
> On Thu, Mar 4, 2021 at 1:42 AM Xuesen Huang <hxseverything@xxxxxxxxx> wrote:
>>
>> From: Xuesen Huang <huangxuesen@xxxxxxxxxxxx>
>>
>> Add BPF_F_ADJ_ROOM_ENCAP_L2_ETH flag to the existing tests which
>> encapsulates the ethernet as the inner l2 header.
>>
>> Update a vxlan encapsulation test case.
>>
>> Signed-off-by: Xuesen Huang <huangxuesen@xxxxxxxxxxxx>
>> Signed-off-by: Li Wang <wangli09@xxxxxxxxxxxx>
>> Signed-off-by: Willem de Bruijn <willemb@xxxxxxxxxx>
>
> Please mark patch target: [PATCH bpf-next]
>
Thanks.
>> ---
>> tools/testing/selftests/bpf/progs/test_tc_tunnel.c | 113 ++++++++++++++++++---
>> tools/testing/selftests/bpf/test_tc_tunnel.sh | 15 ++-
>> 2 files changed, 111 insertions(+), 17 deletions(-)
>
>
>> -static __always_inline int encap_ipv4(struct __sk_buff *skb, __u8 encap_proto,
>> - __u16 l2_proto)
>> +static __always_inline int __encap_ipv4(struct __sk_buff *skb, __u8 encap_proto,
>> + __u16 l2_proto, __u16 ext_proto)
>> {
>> __u16 udp_dst = UDP_PORT;
>> struct iphdr iph_inner;
>> struct v4hdr h_outer;
>> struct tcphdr tcph;
>> int olen, l2_len;
>> + __u8 *l2_hdr = NULL;
>> int tcp_off;
>> __u64 flags;
>>
>> @@ -141,7 +157,11 @@ static __always_inline int encap_ipv4(struct __sk_buff *skb, __u8 encap_proto,
>> break;
>> case ETH_P_TEB:
>> l2_len = ETH_HLEN;
>> - udp_dst = ETH_OVER_UDP_PORT;
>> + if (ext_proto & EXTPROTO_VXLAN) {
>> + udp_dst = VXLAN_UDP_PORT;
>> + l2_len += sizeof(struct vxlanhdr);
>> + } else
>> + udp_dst = ETH_OVER_UDP_PORT;
>> break;
>> }
>> flags |= BPF_F_ADJ_ROOM_ENCAP_L2(l2_len);
>> @@ -171,14 +191,26 @@ static __always_inline int encap_ipv4(struct __sk_buff *skb, __u8 encap_proto,
>> }
>>
>> /* add L2 encap (if specified) */
>> + l2_hdr = (__u8 *)&h_outer + olen;
>> switch (l2_proto) {
>> case ETH_P_MPLS_UC:
>> - *((__u32 *)((__u8 *)&h_outer + olen)) = mpls_label;
>> + *(__u32 *)l2_hdr = mpls_label;
>> break;
>> case ETH_P_TEB:
>> - if (bpf_skb_load_bytes(skb, 0, (__u8 *)&h_outer + olen,
>> - ETH_HLEN))
>> + flags |= BPF_F_ADJ_ROOM_ENCAP_L2_ETH;
>> +
>> + if (ext_proto & EXTPROTO_VXLAN) {
>> + struct vxlanhdr *vxlan_hdr = (struct vxlanhdr *)l2_hdr;
>> +
>> + vxlan_hdr->vx_flags = VXLAN_FLAGS;
>> + vxlan_hdr->vx_vni = bpf_htonl((VXLAN_VNI & VXLAN_VNI_MASK) << 8);
>> +
>> + l2_hdr += sizeof(struct vxlanhdr);
>
> should this be l2_len? (here and ipv6 below)
>
Should be l2_hdr.
It’s a little tricky. l2_len has already been modified above. We use l2_hdr here
to help us to find the address in h_outer to load original Ethernet header which
is different in (eth) and (vxlan + eth).
>> +SEC("encap_vxlan_eth")
>> +int __encap_vxlan_eth(struct __sk_buff *skb)
>> +{
>> + if (skb->protocol == __bpf_constant_htons(ETH_P_IP))
>> + return __encap_ipv4(skb, IPPROTO_UDP,
>> + ETH_P_TEB,
>> + EXTPROTO_VXLAN);
>
> non-standard indentation: align with the opening parenthesis. (here
> and ipv6 below)
Thanks.
