Add test to verify the XDP_TX functionality by generating traffic from a remote node on a specific UDP port and redirecting it back to the sender.
./drivers/net/xdp.py TAP version 13 1..5 ok 1 xdp.test_xdp_native_pass_sb ok 2 xdp.test_xdp_native_pass_mb ok 3 xdp.test_xdp_native_drop_sb ok 4 xdp.test_xdp_native_drop_mb ok 5 xdp.test_xdp_native_tx_mb
Signed-off-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Mohsin Bashir mohsin.bashr@gmail.com --- tools/testing/selftests/drivers/net/xdp.py | 34 ++++++++ .../selftests/net/lib/xdp_native.bpf.c | 80 +++++++++++++++++++ 2 files changed, 114 insertions(+)
diff --git a/tools/testing/selftests/drivers/net/xdp.py b/tools/testing/selftests/drivers/net/xdp.py index 79a8156ed416..b1611e5178a4 100755 --- a/tools/testing/selftests/drivers/net/xdp.py +++ b/tools/testing/selftests/drivers/net/xdp.py @@ -27,6 +27,7 @@ class XDPAction(Enum): """Enum for XDP actions.""" PASS = 0 # Pass the packet up to the stack DROP = 1 # Drop the packet + TX = 2 # Route the packet to the remote host
class XDPStats(Enum): @@ -34,6 +35,7 @@ class XDPStats(Enum): RX = 0 # Count of valid packets received for testing PASS = 1 # Count of packets passed up to the stack DROP = 2 # Count of packets dropped + TX = 3 # Count of incoming packets routed to the remote host
@dataclass @@ -180,6 +182,8 @@ def _get_stats(xdp_map_id): stats_formatted[XDPStats.PASS.value] = val elif stats_dump[key]["formatted"]["key"] == XDPStats.DROP.value: stats_formatted[XDPStats.DROP.value] = val + elif stats_dump[key]["formatted"]["key"] == XDPStats.TX.value: + stats_formatted[XDPStats.TX.value] = val
return stats_formatted
@@ -278,6 +282,35 @@ def test_xdp_native_drop_mb(cfg): _test_drop(cfg, bpf_info, 8000)
+def test_xdp_native_tx_mb(cfg): + """ + Tests the XDP_TX action for a multi-buff case. + + Args: + cfg: Configuration object containing network settings. + """ + cfg.require_cmd("socat", remote=True) + + bpf_info = BPFProgInfo("xdp_prog_frags", "xdp_native.bpf.o", "xdp.frags", 9000) + prog_info = _load_xdp_prog(cfg, bpf_info) + port = rand_port() + + _set_xdp_map("map_xdp_setup", TestConfig.MODE.value, XDPAction.TX.value) + _set_xdp_map("map_xdp_setup", TestConfig.PORT.value, port) + + test_string = ''.join(random.choice(string.ascii_lowercase) for _ in range(8000)) + rx_udp = f"socat -{cfg.addr_ipver} -T 2 -u UDP-RECV:{port},reuseport STDOUT" + tx_udp = f"echo {test_string} | socat -t 2 -u STDIN UDP:{cfg.baddr}:{port}" + + with bkg(rx_udp, host=cfg.remote, exit_wait=True) as rnc: + cmd(tx_udp, host=cfg.remote, shell=True) + + stats = _get_stats(prog_info['maps']['map_xdp_stats']) + + ksft_eq(rnc.stdout.strip(), test_string, "UDP packet exchange failed") + ksft_eq(stats[XDPStats.TX.value], 1, "TX stats mismatch") + + def main(): """ Main function to execute the XDP tests. @@ -294,6 +327,7 @@ def main(): test_xdp_native_pass_mb, test_xdp_native_drop_sb, test_xdp_native_drop_mb, + test_xdp_native_tx_mb, ], args=(cfg,)) ksft_exit() diff --git a/tools/testing/selftests/net/lib/xdp_native.bpf.c b/tools/testing/selftests/net/lib/xdp_native.bpf.c index 90b34b2a4fef..84376710d3fe 100644 --- a/tools/testing/selftests/net/lib/xdp_native.bpf.c +++ b/tools/testing/selftests/net/lib/xdp_native.bpf.c @@ -18,12 +18,14 @@ enum { enum { XDP_MODE_PASS = 0, XDP_MODE_DROP = 1, + XDP_MODE_TX = 2, } xdp_map_modes;
enum { STATS_RX = 0, STATS_PASS = 1, STATS_DROP = 2, + STATS_TX = 3, } xdp_stats;
struct { @@ -117,6 +119,82 @@ static int xdp_mode_drop_handler(struct xdp_md *ctx, __u16 port) return XDP_DROP; }
+static void swap_machdr(void *data) +{ + struct ethhdr *eth = data; + __u8 tmp_mac[ETH_ALEN]; + + __builtin_memcpy(tmp_mac, eth->h_source, ETH_ALEN); + __builtin_memcpy(eth->h_source, eth->h_dest, ETH_ALEN); + __builtin_memcpy(eth->h_dest, tmp_mac, ETH_ALEN); +} + +static int xdp_mode_tx_handler(struct xdp_md *ctx, __u16 port) +{ + void *data_end = (void *)(long)ctx->data_end; + void *data = (void *)(long)ctx->data; + struct udphdr *udph = NULL; + struct ethhdr *eth = data; + + if (data + sizeof(*eth) > data_end) + return XDP_PASS; + + if (eth->h_proto == bpf_htons(ETH_P_IP)) { + struct iphdr *iph = data + sizeof(*eth); + __be32 tmp_ip = iph->saddr; + + if (iph + 1 > (struct iphdr *)data_end || + iph->protocol != IPPROTO_UDP) + return XDP_PASS; + + udph = data + sizeof(*iph) + sizeof(*eth); + + if (udph + 1 > (struct udphdr *)data_end) + return XDP_PASS; + if (udph->dest != bpf_htons(port)) + return XDP_PASS; + + record_stats(ctx, STATS_RX); + swap_machdr((void *)eth); + + iph->saddr = iph->daddr; + iph->daddr = tmp_ip; + + record_stats(ctx, STATS_TX); + + return XDP_TX; + + } else if (eth->h_proto == bpf_htons(ETH_P_IPV6)) { + struct ipv6hdr *ipv6h = data + sizeof(*eth); + struct in6_addr tmp_ipv6; + + if (ipv6h + 1 > (struct ipv6hdr *)data_end || + ipv6h->nexthdr != IPPROTO_UDP) + return XDP_PASS; + + udph = data + sizeof(*ipv6h) + sizeof(*eth); + + if (udph + 1 > (struct udphdr *)data_end) + return XDP_PASS; + if (udph->dest != bpf_htons(port)) + return XDP_PASS; + + record_stats(ctx, STATS_RX); + swap_machdr((void *)eth); + + __builtin_memcpy(&tmp_ipv6, &ipv6h->saddr, sizeof(tmp_ipv6)); + __builtin_memcpy(&ipv6h->saddr, &ipv6h->daddr, + sizeof(tmp_ipv6)); + __builtin_memcpy(&ipv6h->daddr, &tmp_ipv6, sizeof(tmp_ipv6)); + + record_stats(ctx, STATS_TX); + + return XDP_TX; + } + + return XDP_PASS; +} + static int xdp_prog_common(struct xdp_md *ctx) { __u32 key, *port; @@ -137,6 +215,8 @@ static int xdp_prog_common(struct xdp_md *ctx) return xdp_mode_pass(ctx, (__u16)(*port)); case XDP_MODE_DROP: return xdp_mode_drop_handler(ctx, (__u16)(*port)); + case XDP_MODE_TX: + return xdp_mode_tx_handler(ctx, (__u16)(*port)); }
/* Default action is to simple pass */