Benjamin Beckmeyer <beb@xxxxxxxxxxxx> writes:
> Hi Toke,
>
>>> Hi all,
>>>
>>> I hope you could help me with a static variable problem in xdp.
>>> Here is my source:
>>>
>>> static __u32 last_xid = 0;
>>>
>>> static __always_inline int profinet_process_packet(struct xdp_md *ctx, __u64 off) {
>>> void *data_end = (void *)(long)ctx->data_end;
>>> void *data = (void *)(long)ctx->data;
>>> struct profinet_hdr *p_hdr;
>>> __u16 profinet_frame_id;
>>> // static __u32 last_xid;
>>>
>>> p_hdr = data + off;
>>>
>>> if (p_hdr + 1 > data_end)
>>> return XDP_DROP;
>>>
>>> profinet_frame_id = bpf_htons(p_hdr->frame_id);
>>>
>>> if ((profinet_frame_id >= 0x0100 && profinet_frame_id <=0x7fff) ||
>>> (profinet_frame_id == 0x0020) ||
>>> (profinet_frame_id == 0xbbff) ||
>>> (profinet_frame_id == 0xfefc) ||
>>> (profinet_frame_id == 0xf7ff))
>>> return XDP_DROP;
>>>
>>> if (p_hdr->xid == last_xid)
>>> return XDP_DROP;
>>> else
>>> last_xid = p_hdr->xid;
>>>
>>> return XDP_PASS;
>>> }
>>>
>>> At the moment I'm using kernel version 6.0.2 and iproute2-6.0.0.
>>> I also tried to load the the filter with xdp_loader (xdp_tools).
>>>
>>> Output from ip:
>>> $ ip link set dev eth0 xdpgeneric obj xdp_prog_kern.o sec
>>> eks_filter
>>>
>>> Prog section 'eks_filter' rejected: Permission denied (13)!
>>> - Type: 6
>>> - Instructions: 48 (0 over limit)
>>> - License: GPL
>>>
>>> Verifier analysis:
>>>
>>> Error fetching program/map!
>>>
>>> Output from xdp_loader:
>>> $ ./xdp_loader -deth0 -A --filename xdp_prog_kern.o --pro
>>> gsec eks_filter
>>> libbpf: failed to guess program type based on ELF section name 'eks_filter'
>>> libbpf: supported section(type) names are: socket kprobe/ uprobe/
>>> kretprobe/ uretprobe/ classifier action tracepoint/ tp/ raw_tracepoint/
>>> raw_tp/ tp_btf/ xdp perf_event lwt_in lwt_out lwt_xmit lwt_seg6local
>>> cgroup_skb/ingress cgroup_skb/egress cgroup/skb cgroup/sock
>>> cgroup/post_bind4 cgroup/post_bind6 cgroup/dev sockops sk_skb/stream_parser
>>> sk_skb/stream_verdict sk_skb sk_msg lirc_mode2 flow_dissector cgroup/bind4
>>> cgroup/bind6 cgroup/connect4 cgroup/connect6 cgroup/sendmsg4
>>> cgroup/sendmsg6 cgroup/recvmsg4 cgroup/recvmsg6 cgroup/sysctl
>>> cgroup/getsockopt cgroup/setsockopt
>>> Success: Loaded BPF-object(xdp_prog_kern.o) and used section(eks_filter)
>>> - XDP prog attached on device:eth0(ifindex:2)
>>> - Pinning maps in /sys/fs/bpf/eth0/
>>> libbpf: failed to pin map: Operation not permitted
>>> ERR: pinning maps
>> This does not look like the output of the xdp-loader from xdp-tools; are
>> you using the code from the xdp-tutorial? Try using the one from
>> xdp-tools instead...
>>
>> Also, there's a hint here:
>>
>>> libbpf: failed to guess program type based on ELF section name 'eks_filter'
>> You should use SEC("xdp") for XDP programs instead of custom section
>> names, those are deprecated...
>>
>> -Toke
>
> thanks for your reply. I forget about one thing. I'm cross compiling the xdp-loader
> for armv7. So far it looks good. I had a little fight with the xdp-loader but it
> seems to work now. The hint with SEC was really good.
>
> It seems that not the xdp program was the problem, it was more the problem which
> tool you use to load it.
>
> xdp-loader no problem, while ip throws still this output.
>
> Anyways, it works. Thanks for your help.
Cool! You're welcome! :)
-Toke
|