From: Stanislav Fomichev sdf@google.com
[ Upstream commit 68f8e3d4b916531ea3bb8b83e35138cf78f2fce5 ]
LWT_XMIT to test L3 case, TC to test L2 case.
v2: - s/veth_ifindex/ipip_ifindex/ in two places (Martin) - add comment about which condition triggers the rejection (Martin)
Signed-off-by: Stanislav Fomichev sdf@google.com Link: https://lore.kernel.org/r/20221121180340.1983627-2-sdf@google.com Signed-off-by: Martin KaFai Lau martin.lau@kernel.org Stable-dep-of: 8ac88eece800 ("selftests/bpf: Mount debugfs in setns_by_fd") Signed-off-by: Sasha Levin sashal@kernel.org --- .../selftests/bpf/prog_tests/empty_skb.c | 146 ++++++++++++++++++ tools/testing/selftests/bpf/progs/empty_skb.c | 37 +++++ 2 files changed, 183 insertions(+) create mode 100644 tools/testing/selftests/bpf/prog_tests/empty_skb.c create mode 100644 tools/testing/selftests/bpf/progs/empty_skb.c
diff --git a/tools/testing/selftests/bpf/prog_tests/empty_skb.c b/tools/testing/selftests/bpf/prog_tests/empty_skb.c new file mode 100644 index 000000000000..32dd731e9070 --- /dev/null +++ b/tools/testing/selftests/bpf/prog_tests/empty_skb.c @@ -0,0 +1,146 @@ +// SPDX-License-Identifier: GPL-2.0 +#include <test_progs.h> +#include <network_helpers.h> +#include <net/if.h> +#include "empty_skb.skel.h" + +#define SYS(cmd) ({ \ + if (!ASSERT_OK(system(cmd), (cmd))) \ + goto out; \ +}) + +void test_empty_skb(void) +{ + LIBBPF_OPTS(bpf_test_run_opts, tattr); + struct empty_skb *bpf_obj = NULL; + struct nstoken *tok = NULL; + struct bpf_program *prog; + char eth_hlen_pp[15]; + char eth_hlen[14]; + int veth_ifindex; + int ipip_ifindex; + int err; + int i; + + struct { + const char *msg; + const void *data_in; + __u32 data_size_in; + int *ifindex; + int err; + int ret; + bool success_on_tc; + } tests[] = { + /* Empty packets are always rejected. */ + + { + /* BPF_PROG_RUN ETH_HLEN size check */ + .msg = "veth empty ingress packet", + .data_in = NULL, + .data_size_in = 0, + .ifindex = &veth_ifindex, + .err = -EINVAL, + }, + { + /* BPF_PROG_RUN ETH_HLEN size check */ + .msg = "ipip empty ingress packet", + .data_in = NULL, + .data_size_in = 0, + .ifindex = &ipip_ifindex, + .err = -EINVAL, + }, + + /* ETH_HLEN-sized packets: + * - can not be redirected at LWT_XMIT + * - can be redirected at TC to non-tunneling dest + */ + + { + /* __bpf_redirect_common */ + .msg = "veth ETH_HLEN packet ingress", + .data_in = eth_hlen, + .data_size_in = sizeof(eth_hlen), + .ifindex = &veth_ifindex, + .ret = -ERANGE, + .success_on_tc = true, + }, + { + /* __bpf_redirect_no_mac + * + * lwt: skb->len=0 <= skb_network_offset=0 + * tc: skb->len=14 <= skb_network_offset=14 + */ + .msg = "ipip ETH_HLEN packet ingress", + .data_in = eth_hlen, + .data_size_in = sizeof(eth_hlen), + .ifindex = &ipip_ifindex, + .ret = -ERANGE, + }, + + /* ETH_HLEN+1-sized packet should be redirected. */ + + { + .msg = "veth ETH_HLEN+1 packet ingress", + .data_in = eth_hlen_pp, + .data_size_in = sizeof(eth_hlen_pp), + .ifindex = &veth_ifindex, + }, + { + .msg = "ipip ETH_HLEN+1 packet ingress", + .data_in = eth_hlen_pp, + .data_size_in = sizeof(eth_hlen_pp), + .ifindex = &ipip_ifindex, + }, + }; + + SYS("ip netns add empty_skb"); + tok = open_netns("empty_skb"); + SYS("ip link add veth0 type veth peer veth1"); + SYS("ip link set dev veth0 up"); + SYS("ip link set dev veth1 up"); + SYS("ip addr add 10.0.0.1/8 dev veth0"); + SYS("ip addr add 10.0.0.2/8 dev veth1"); + veth_ifindex = if_nametoindex("veth0"); + + SYS("ip link add ipip0 type ipip local 10.0.0.1 remote 10.0.0.2"); + SYS("ip link set ipip0 up"); + SYS("ip addr add 192.168.1.1/16 dev ipip0"); + ipip_ifindex = if_nametoindex("ipip0"); + + bpf_obj = empty_skb__open_and_load(); + if (!ASSERT_OK_PTR(bpf_obj, "open skeleton")) + goto out; + + for (i = 0; i < ARRAY_SIZE(tests); i++) { + bpf_object__for_each_program(prog, bpf_obj->obj) { + char buf[128]; + bool at_tc = !strncmp(bpf_program__section_name(prog), "tc", 2); + + tattr.data_in = tests[i].data_in; + tattr.data_size_in = tests[i].data_size_in; + + tattr.data_size_out = 0; + bpf_obj->bss->ifindex = *tests[i].ifindex; + bpf_obj->bss->ret = 0; + err = bpf_prog_test_run_opts(bpf_program__fd(prog), &tattr); + sprintf(buf, "err: %s [%s]", tests[i].msg, bpf_program__name(prog)); + + if (at_tc && tests[i].success_on_tc) + ASSERT_GE(err, 0, buf); + else + ASSERT_EQ(err, tests[i].err, buf); + sprintf(buf, "ret: %s [%s]", tests[i].msg, bpf_program__name(prog)); + if (at_tc && tests[i].success_on_tc) + ASSERT_GE(bpf_obj->bss->ret, 0, buf); + else + ASSERT_EQ(bpf_obj->bss->ret, tests[i].ret, buf); + } + } + +out: + if (bpf_obj) + empty_skb__destroy(bpf_obj); + if (tok) + close_netns(tok); + system("ip netns del empty_skb"); +} diff --git a/tools/testing/selftests/bpf/progs/empty_skb.c b/tools/testing/selftests/bpf/progs/empty_skb.c new file mode 100644 index 000000000000..4b0cd6753251 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/empty_skb.c @@ -0,0 +1,37 @@ +// SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause +#include <linux/bpf.h> +#include <bpf/bpf_helpers.h> +#include <bpf/bpf_endian.h> + +char _license[] SEC("license") = "GPL"; + +int ifindex; +int ret; + +SEC("lwt_xmit") +int redirect_ingress(struct __sk_buff *skb) +{ + ret = bpf_clone_redirect(skb, ifindex, BPF_F_INGRESS); + return 0; +} + +SEC("lwt_xmit") +int redirect_egress(struct __sk_buff *skb) +{ + ret = bpf_clone_redirect(skb, ifindex, 0); + return 0; +} + +SEC("tc") +int tc_redirect_ingress(struct __sk_buff *skb) +{ + ret = bpf_clone_redirect(skb, ifindex, BPF_F_INGRESS); + return 0; +} + +SEC("tc") +int tc_redirect_egress(struct __sk_buff *skb) +{ + ret = bpf_clone_redirect(skb, ifindex, 0); + return 0; +}