diff options
Diffstat (limited to 'tools/testing/selftests/bpf/progs/xsk_xdp_progs.c')
| -rw-r--r-- | tools/testing/selftests/bpf/progs/xsk_xdp_progs.c | 50 |
1 files changed, 50 insertions, 0 deletions
diff --git a/tools/testing/selftests/bpf/progs/xsk_xdp_progs.c b/tools/testing/selftests/bpf/progs/xsk_xdp_progs.c index ccde6a4c6319..683306db8594 100644 --- a/tools/testing/selftests/bpf/progs/xsk_xdp_progs.c +++ b/tools/testing/selftests/bpf/progs/xsk_xdp_progs.c @@ -4,6 +4,8 @@ #include <linux/bpf.h> #include <bpf/bpf_helpers.h> #include <linux/if_ether.h> +#include <linux/ip.h> +#include <linux/errno.h> #include "xsk_xdp_common.h" struct { @@ -14,6 +16,7 @@ struct { } xsk SEC(".maps"); static unsigned int idx; +int adjust_value = 0; int count = 0; SEC("xdp.frags") int xsk_def_prog(struct xdp_md *xdp) @@ -70,4 +73,51 @@ SEC("xdp") int xsk_xdp_shared_umem(struct xdp_md *xdp) return bpf_redirect_map(&xsk, idx, XDP_DROP); } +SEC("xdp.frags") int xsk_xdp_adjust_tail(struct xdp_md *xdp) +{ + __u32 buff_len, curr_buff_len; + int ret; + + buff_len = bpf_xdp_get_buff_len(xdp); + if (buff_len == 0) + return XDP_DROP; + + ret = bpf_xdp_adjust_tail(xdp, adjust_value); + if (ret < 0) { + /* Handle unsupported cases */ + if (ret == -EOPNOTSUPP) { + /* Set adjust_value to -EOPNOTSUPP to indicate to userspace that this case + * is unsupported + */ + adjust_value = -EOPNOTSUPP; + return bpf_redirect_map(&xsk, 0, XDP_DROP); + } + + return XDP_DROP; + } + + curr_buff_len = bpf_xdp_get_buff_len(xdp); + if (curr_buff_len != buff_len + adjust_value) + return XDP_DROP; + + if (curr_buff_len > buff_len) { + __u32 *pkt_data = (void *)(long)xdp->data; + __u32 len, words_to_end, seq_num; + + len = curr_buff_len - PKT_HDR_ALIGN; + words_to_end = len / sizeof(*pkt_data) - 1; + seq_num = words_to_end; + + /* Convert sequence number to network byte order. Store this in the last 4 bytes of + * the packet. Use 'adjust_value' to determine the position at the end of the + * packet for storing the sequence number. + */ + seq_num = __constant_htonl(words_to_end); + bpf_xdp_store_bytes(xdp, curr_buff_len - sizeof(seq_num), &seq_num, + sizeof(seq_num)); + } + + return bpf_redirect_map(&xsk, 0, XDP_DROP); +} + char _license[] SEC("license") = "GPL"; |