diff options
Diffstat (limited to 'samples/bpf/xdp_rxq_info_kern.c')
| -rw-r--r-- | samples/bpf/xdp_rxq_info_kern.c | 43 |
1 files changed, 43 insertions, 0 deletions
diff --git a/samples/bpf/xdp_rxq_info_kern.c b/samples/bpf/xdp_rxq_info_kern.c index 3fd209291653..222a83eed1cb 100644 --- a/samples/bpf/xdp_rxq_info_kern.c +++ b/samples/bpf/xdp_rxq_info_kern.c @@ -4,6 +4,8 @@ * Example howto extract XDP RX-queue info */ #include <uapi/linux/bpf.h> +#include <uapi/linux/if_ether.h> +#include <uapi/linux/in.h> #include "bpf_helpers.h" /* Config setup from with userspace @@ -14,6 +16,12 @@ struct config { __u32 action; int ifindex; + __u32 options; +}; +enum cfg_options_flags { + NO_TOUCH = 0x0U, + READ_MEM = 0x1U, + SWAP_MAC = 0x2U, }; struct bpf_map_def SEC("maps") config_map = { .type = BPF_MAP_TYPE_ARRAY, @@ -45,6 +53,23 @@ struct bpf_map_def SEC("maps") rx_queue_index_map = { .max_entries = MAX_RXQs + 1, }; +static __always_inline +void swap_src_dst_mac(void *data) +{ + unsigned short *p = data; + unsigned short dst[3]; + + dst[0] = p[0]; + dst[1] = p[1]; + dst[2] = p[2]; + p[0] = p[3]; + p[1] = p[4]; + p[2] = p[5]; + p[3] = dst[0]; + p[4] = dst[1]; + p[5] = dst[2]; +} + SEC("xdp_prog0") int xdp_prognum0(struct xdp_md *ctx) { @@ -90,6 +115,24 @@ int xdp_prognum0(struct xdp_md *ctx) if (key == MAX_RXQs) rxq_rec->issue++; + /* Default: Don't touch packet data, only count packets */ + if (unlikely(config->options & (READ_MEM|SWAP_MAC))) { + struct ethhdr *eth = data; + + if (eth + 1 > data_end) + return XDP_ABORTED; + + /* Avoid compiler removing this: Drop non 802.3 Ethertypes */ + if (ntohs(eth->h_proto) < ETH_P_802_3_MIN) + return XDP_ABORTED; + + /* XDP_TX requires changing MAC-addrs, else HW may drop. + * Can also be enabled with --swapmac (for test purposes) + */ + if (unlikely(config->options & SWAP_MAC)) + swap_src_dst_mac(data); + } + return config->action; } |