diff options
Diffstat (limited to 'tools/testing/selftests/net/lib/xdp_metadata.bpf.c')
| -rw-r--r-- | tools/testing/selftests/net/lib/xdp_metadata.bpf.c | 163 |
1 files changed, 163 insertions, 0 deletions
diff --git a/tools/testing/selftests/net/lib/xdp_metadata.bpf.c b/tools/testing/selftests/net/lib/xdp_metadata.bpf.c new file mode 100644 index 000000000000..f71f59215239 --- /dev/null +++ b/tools/testing/selftests/net/lib/xdp_metadata.bpf.c @@ -0,0 +1,163 @@ +// SPDX-License-Identifier: GPL-2.0 + +#include <stddef.h> +#include <linux/bpf.h> +#include <linux/in.h> +#include <linux/if_ether.h> +#include <linux/ip.h> +#include <linux/ipv6.h> +#include <linux/udp.h> +#include <linux/tcp.h> +#include <bpf/bpf_endian.h> +#include <bpf/bpf_helpers.h> + +enum { + XDP_PORT = 1, + XDP_PROTO = 4, +} xdp_map_setup_keys; + +struct { + __uint(type, BPF_MAP_TYPE_ARRAY); + __uint(max_entries, 5); + __type(key, __u32); + __type(value, __s32); +} map_xdp_setup SEC(".maps"); + +/* RSS hash results: key 0 = hash, key 1 = hash type, + * key 2 = packet count, key 3 = error count. + */ +enum { + RSS_KEY_HASH = 0, + RSS_KEY_TYPE = 1, + RSS_KEY_PKT_CNT = 2, + RSS_KEY_ERR_CNT = 3, +}; + +struct { + __uint(type, BPF_MAP_TYPE_ARRAY); + __type(key, __u32); + __type(value, __u32); + __uint(max_entries, 4); +} map_rss SEC(".maps"); + +/* Mirror of enum xdp_rss_hash_type from include/net/xdp.h. + * Needed because the enum is not part of UAPI headers. + */ +enum xdp_rss_hash_type { + XDP_RSS_L3_IPV4 = 1U << 0, + XDP_RSS_L3_IPV6 = 1U << 1, + XDP_RSS_L3_DYNHDR = 1U << 2, + XDP_RSS_L4 = 1U << 3, + XDP_RSS_L4_TCP = 1U << 4, + XDP_RSS_L4_UDP = 1U << 5, + XDP_RSS_L4_SCTP = 1U << 6, + XDP_RSS_L4_IPSEC = 1U << 7, + XDP_RSS_L4_ICMP = 1U << 8, +}; + +extern int bpf_xdp_metadata_rx_hash(const struct xdp_md *ctx, __u32 *hash, + enum xdp_rss_hash_type *rss_type) __ksym; + +static __always_inline __u16 get_dest_port(void *l4, void *data_end, + __u8 protocol) +{ + if (protocol == IPPROTO_UDP) { + struct udphdr *udp = l4; + + if ((void *)(udp + 1) > data_end) + return 0; + return udp->dest; + } else if (protocol == IPPROTO_TCP) { + struct tcphdr *tcp = l4; + + if ((void *)(tcp + 1) > data_end) + return 0; + return tcp->dest; + } + + return 0; +} + +SEC("xdp") +int xdp_rss_hash(struct xdp_md *ctx) +{ + void *data_end = (void *)(long)ctx->data_end; + void *data = (void *)(long)ctx->data; + enum xdp_rss_hash_type rss_type = 0; + struct ethhdr *eth = data; + __u8 l4_proto = 0; + __u32 hash = 0; + __u32 key, val; + void *l4 = NULL; + __u32 *cnt; + int ret; + + if ((void *)(eth + 1) > data_end) + return XDP_PASS; + + if (eth->h_proto == bpf_htons(ETH_P_IP)) { + struct iphdr *iph = (void *)(eth + 1); + + if ((void *)(iph + 1) > data_end) + return XDP_PASS; + l4_proto = iph->protocol; + l4 = (void *)(iph + 1); + } else if (eth->h_proto == bpf_htons(ETH_P_IPV6)) { + struct ipv6hdr *ip6h = (void *)(eth + 1); + + if ((void *)(ip6h + 1) > data_end) + return XDP_PASS; + l4_proto = ip6h->nexthdr; + l4 = (void *)(ip6h + 1); + } + + if (!l4) + return XDP_PASS; + + /* Filter on the configured protocol (map_xdp_setup key XDP_PROTO). + * When set, only process packets matching the requested L4 protocol. + */ + key = XDP_PROTO; + __s32 *proto_cfg = bpf_map_lookup_elem(&map_xdp_setup, &key); + + if (proto_cfg && *proto_cfg != 0 && l4_proto != (__u8)*proto_cfg) + return XDP_PASS; + + /* Filter on the configured port (map_xdp_setup key XDP_PORT). + * Only applies to protocols with ports (UDP, TCP). + */ + key = XDP_PORT; + __s32 *port_cfg = bpf_map_lookup_elem(&map_xdp_setup, &key); + + if (port_cfg && *port_cfg != 0) { + __u16 dest = get_dest_port(l4, data_end, l4_proto); + + if (!dest || bpf_ntohs(dest) != (__u16)*port_cfg) + return XDP_PASS; + } + + ret = bpf_xdp_metadata_rx_hash(ctx, &hash, &rss_type); + if (ret < 0) { + key = RSS_KEY_ERR_CNT; + cnt = bpf_map_lookup_elem(&map_rss, &key); + if (cnt) + __sync_fetch_and_add(cnt, 1); + return XDP_PASS; + } + + key = RSS_KEY_HASH; + bpf_map_update_elem(&map_rss, &key, &hash, BPF_ANY); + + key = RSS_KEY_TYPE; + val = (__u32)rss_type; + bpf_map_update_elem(&map_rss, &key, &val, BPF_ANY); + + key = RSS_KEY_PKT_CNT; + cnt = bpf_map_lookup_elem(&map_rss, &key); + if (cnt) + __sync_fetch_and_add(cnt, 1); + + return XDP_PASS; +} + +char _license[] SEC("license") = "GPL"; |