1// SPDX-License-Identifier: GPL-2.0
  2#include <test_progs.h>
  3#include <network_helpers.h>
  4#include <net/if.h>
  5#include "empty_skb.skel.h"
  6
  7void test_empty_skb(void)
  8{
  9	LIBBPF_OPTS(bpf_test_run_opts, tattr);
 10	struct empty_skb *bpf_obj = NULL;
 11	struct nstoken *tok = NULL;
 12	struct bpf_program *prog;
 13	char eth_hlen_pp[15];
 14	char eth_hlen[14];
 15	int veth_ifindex;
 16	int ipip_ifindex;
 17	int err;
 18	int i;
 19
 20	struct {
 21		const char *msg;
 22		const void *data_in;
 23		__u32 data_size_in;
 24		int *ifindex;
 25		int err;
 26		int ret;
 27		int lwt_egress_ret; /* expected retval at lwt/egress */
 28		bool success_on_tc;
 29	} tests[] = {
 30		/* Empty packets are always rejected. */
 31
 32		{
 33			/* BPF_PROG_RUN ETH_HLEN size check */
 34			.msg = "veth empty ingress packet",
 35			.data_in = NULL,
 36			.data_size_in = 0,
 37			.ifindex = &veth_ifindex,
 38			.err = -EINVAL,
 39		},
 40		{
 41			/* BPF_PROG_RUN ETH_HLEN size check */
 42			.msg = "ipip empty ingress packet",
 43			.data_in = NULL,
 44			.data_size_in = 0,
 45			.ifindex = &ipip_ifindex,
 46			.err = -EINVAL,
 47		},
 48
 49		/* ETH_HLEN-sized packets:
 50		 * - can not be redirected at LWT_XMIT
 51		 * - can be redirected at TC to non-tunneling dest
 52		 */
 53
 54		{
 55			/* __bpf_redirect_common */
 56			.msg = "veth ETH_HLEN packet ingress",
 57			.data_in = eth_hlen,
 58			.data_size_in = sizeof(eth_hlen),
 59			.ifindex = &veth_ifindex,
 60			.ret = -ERANGE,
 61			.lwt_egress_ret = -ERANGE,
 62			.success_on_tc = true,
 63		},
 64		{
 65			/* __bpf_redirect_no_mac
 66			 *
 67			 * lwt: skb->len=0 <= skb_network_offset=0
 68			 * tc: skb->len=14 <= skb_network_offset=14
 69			 */
 70			.msg = "ipip ETH_HLEN packet ingress",
 71			.data_in = eth_hlen,
 72			.data_size_in = sizeof(eth_hlen),
 73			.ifindex = &ipip_ifindex,
 74			.ret = -ERANGE,
 75			.lwt_egress_ret = -ERANGE,
 76		},
 77
 78		/* ETH_HLEN+1-sized packet should be redirected. */
 79
 80		{
 81			.msg = "veth ETH_HLEN+1 packet ingress",
 82			.data_in = eth_hlen_pp,
 83			.data_size_in = sizeof(eth_hlen_pp),
 84			.ifindex = &veth_ifindex,
 85			.lwt_egress_ret = 1, /* veth_xmit NET_XMIT_DROP */
 86		},
 87		{
 88			.msg = "ipip ETH_HLEN+1 packet ingress",
 89			.data_in = eth_hlen_pp,
 90			.data_size_in = sizeof(eth_hlen_pp),
 91			.ifindex = &ipip_ifindex,
 92		},
 93	};
 94
 95	SYS(out, "ip netns add empty_skb");
 96	tok = open_netns("empty_skb");
 97	if (!ASSERT_OK_PTR(tok, "setns"))
 98		goto out;
 99	SYS(out, "ip link add veth0 type veth peer veth1");
100	SYS(out, "ip link set dev veth0 up");
101	SYS(out, "ip link set dev veth1 up");
102	SYS(out, "ip addr add 10.0.0.1/8 dev veth0");
103	SYS(out, "ip addr add 10.0.0.2/8 dev veth1");
104	veth_ifindex = if_nametoindex("veth0");
105
106	SYS(out, "ip link add ipip0 type ipip local 10.0.0.1 remote 10.0.0.2");
107	SYS(out, "ip link set ipip0 up");
108	SYS(out, "ip addr add 192.168.1.1/16 dev ipip0");
109	ipip_ifindex = if_nametoindex("ipip0");
110
111	bpf_obj = empty_skb__open_and_load();
112	if (!ASSERT_OK_PTR(bpf_obj, "open skeleton"))
113		goto out;
114
115	for (i = 0; i < ARRAY_SIZE(tests); i++) {
116		bpf_object__for_each_program(prog, bpf_obj->obj) {
117			bool at_egress = strstr(bpf_program__name(prog), "egress") != NULL;
118			bool at_tc = !strncmp(bpf_program__section_name(prog), "tc", 2);
119			int expected_ret;
120			char buf[128];
121
122			expected_ret = at_egress && !at_tc ? tests[i].lwt_egress_ret : tests[i].ret;
123
124			tattr.data_in = tests[i].data_in;
125			tattr.data_size_in = tests[i].data_size_in;
126
127			tattr.data_size_out = 0;
128			bpf_obj->bss->ifindex = *tests[i].ifindex;
129			bpf_obj->bss->ret = 0;
130			err = bpf_prog_test_run_opts(bpf_program__fd(prog), &tattr);
131			sprintf(buf, "err: %s [%s]", tests[i].msg, bpf_program__name(prog));
132
133			if (at_tc && tests[i].success_on_tc)
134				ASSERT_GE(err, 0, buf);
135			else
136				ASSERT_EQ(err, tests[i].err, buf);
137			sprintf(buf, "ret: %s [%s]", tests[i].msg, bpf_program__name(prog));
138			if (at_tc && tests[i].success_on_tc)
139				ASSERT_GE(bpf_obj->bss->ret, 0, buf);
140			else
141				ASSERT_EQ(bpf_obj->bss->ret, expected_ret, buf);
142		}
143	}
144
145out:
146	if (bpf_obj)
147		empty_skb__destroy(bpf_obj);
148	if (tok)
149		close_netns(tok);
150	SYS_NOFAIL("ip netns del empty_skb");
151}