1// SPDX-License-Identifier: GPL-2.0
2/* Copyright (c) 2023 Meta Platforms, Inc. and affiliates. */
3
4#include <linux/rtnetlink.h>
5#include <sys/types.h>
6#include <net/if.h>
7
8#include "test_progs.h"
9#include "network_helpers.h"
10#include "fib_lookup.skel.h"
11
12#define NS_TEST			"fib_lookup_ns"
13#define IPV6_IFACE_ADDR		"face::face"
14#define IPV6_IFACE_ADDR_SEC	"cafe::cafe"
15#define IPV6_ADDR_DST		"face::3"
16#define IPV6_NUD_FAILED_ADDR	"face::1"
17#define IPV6_NUD_STALE_ADDR	"face::2"
18#define IPV4_IFACE_ADDR		"10.0.0.254"
19#define IPV4_IFACE_ADDR_SEC	"10.1.0.254"
20#define IPV4_ADDR_DST		"10.2.0.254"
21#define IPV4_NUD_FAILED_ADDR	"10.0.0.1"
22#define IPV4_NUD_STALE_ADDR	"10.0.0.2"
23#define IPV4_TBID_ADDR		"172.0.0.254"
24#define IPV4_TBID_NET		"172.0.0.0"
25#define IPV4_TBID_DST		"172.0.0.2"
26#define IPV6_TBID_ADDR		"fd00::FFFF"
27#define IPV6_TBID_NET		"fd00::"
28#define IPV6_TBID_DST		"fd00::2"
29#define DMAC			"11:11:11:11:11:11"
30#define DMAC_INIT { 0x11, 0x11, 0x11, 0x11, 0x11, 0x11, }
31#define DMAC2			"01:01:01:01:01:01"
32#define DMAC_INIT2 { 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, }
33
34struct fib_lookup_test {
35	const char *desc;
36	const char *daddr;
37	int expected_ret;
38	const char *expected_src;
39	int lookup_flags;
40	__u32 tbid;
41	__u8 dmac[6];
42};
43
44static const struct fib_lookup_test tests[] = {
45	{ .desc = "IPv6 failed neigh",
46	  .daddr = IPV6_NUD_FAILED_ADDR, .expected_ret = BPF_FIB_LKUP_RET_NO_NEIGH, },
47	{ .desc = "IPv6 stale neigh",
48	  .daddr = IPV6_NUD_STALE_ADDR, .expected_ret = BPF_FIB_LKUP_RET_SUCCESS,
49	  .dmac = DMAC_INIT, },
50	{ .desc = "IPv6 skip neigh",
51	  .daddr = IPV6_NUD_FAILED_ADDR, .expected_ret = BPF_FIB_LKUP_RET_SUCCESS,
52	  .lookup_flags = BPF_FIB_LOOKUP_SKIP_NEIGH, },
53	{ .desc = "IPv4 failed neigh",
54	  .daddr = IPV4_NUD_FAILED_ADDR, .expected_ret = BPF_FIB_LKUP_RET_NO_NEIGH, },
55	{ .desc = "IPv4 stale neigh",
56	  .daddr = IPV4_NUD_STALE_ADDR, .expected_ret = BPF_FIB_LKUP_RET_SUCCESS,
57	  .dmac = DMAC_INIT, },
58	{ .desc = "IPv4 skip neigh",
59	  .daddr = IPV4_NUD_FAILED_ADDR, .expected_ret = BPF_FIB_LKUP_RET_SUCCESS,
60	  .lookup_flags = BPF_FIB_LOOKUP_SKIP_NEIGH, },
61	{ .desc = "IPv4 TBID lookup failure",
62	  .daddr = IPV4_TBID_DST, .expected_ret = BPF_FIB_LKUP_RET_NOT_FWDED,
63	  .lookup_flags = BPF_FIB_LOOKUP_DIRECT | BPF_FIB_LOOKUP_TBID,
64	  .tbid = RT_TABLE_MAIN, },
65	{ .desc = "IPv4 TBID lookup success",
66	  .daddr = IPV4_TBID_DST, .expected_ret = BPF_FIB_LKUP_RET_SUCCESS,
67	  .lookup_flags = BPF_FIB_LOOKUP_DIRECT | BPF_FIB_LOOKUP_TBID, .tbid = 100,
68	  .dmac = DMAC_INIT2, },
69	{ .desc = "IPv6 TBID lookup failure",
70	  .daddr = IPV6_TBID_DST, .expected_ret = BPF_FIB_LKUP_RET_NOT_FWDED,
71	  .lookup_flags = BPF_FIB_LOOKUP_DIRECT | BPF_FIB_LOOKUP_TBID,
72	  .tbid = RT_TABLE_MAIN, },
73	{ .desc = "IPv6 TBID lookup success",
74	  .daddr = IPV6_TBID_DST, .expected_ret = BPF_FIB_LKUP_RET_SUCCESS,
75	  .lookup_flags = BPF_FIB_LOOKUP_DIRECT | BPF_FIB_LOOKUP_TBID, .tbid = 100,
76	  .dmac = DMAC_INIT2, },
77	{ .desc = "IPv4 set src addr from netdev",
78	  .daddr = IPV4_NUD_FAILED_ADDR, .expected_ret = BPF_FIB_LKUP_RET_SUCCESS,
79	  .expected_src = IPV4_IFACE_ADDR,
80	  .lookup_flags = BPF_FIB_LOOKUP_SRC | BPF_FIB_LOOKUP_SKIP_NEIGH, },
81	{ .desc = "IPv6 set src addr from netdev",
82	  .daddr = IPV6_NUD_FAILED_ADDR, .expected_ret = BPF_FIB_LKUP_RET_SUCCESS,
83	  .expected_src = IPV6_IFACE_ADDR,
84	  .lookup_flags = BPF_FIB_LOOKUP_SRC | BPF_FIB_LOOKUP_SKIP_NEIGH, },
85	{ .desc = "IPv4 set prefsrc addr from route",
86	  .daddr = IPV4_ADDR_DST, .expected_ret = BPF_FIB_LKUP_RET_SUCCESS,
87	  .expected_src = IPV4_IFACE_ADDR_SEC,
88	  .lookup_flags = BPF_FIB_LOOKUP_SRC | BPF_FIB_LOOKUP_SKIP_NEIGH, },
89	{ .desc = "IPv6 set prefsrc addr route",
90	  .daddr = IPV6_ADDR_DST, .expected_ret = BPF_FIB_LKUP_RET_SUCCESS,
91	  .expected_src = IPV6_IFACE_ADDR_SEC,
92	  .lookup_flags = BPF_FIB_LOOKUP_SRC | BPF_FIB_LOOKUP_SKIP_NEIGH, },
93};
94
95static int ifindex;
96
97static int setup_netns(void)
98{
99	int err;
100
101	SYS(fail, "ip link add veth1 type veth peer name veth2");
102	SYS(fail, "ip link set dev veth1 up");
103	SYS(fail, "ip link set dev veth2 up");
104
105	err = write_sysctl("/proc/sys/net/ipv4/neigh/veth1/gc_stale_time", "900");
106	if (!ASSERT_OK(err, "write_sysctl(net.ipv4.neigh.veth1.gc_stale_time)"))
107		goto fail;
108
109	err = write_sysctl("/proc/sys/net/ipv6/neigh/veth1/gc_stale_time", "900");
110	if (!ASSERT_OK(err, "write_sysctl(net.ipv6.neigh.veth1.gc_stale_time)"))
111		goto fail;
112
113	SYS(fail, "ip addr add %s/64 dev veth1 nodad", IPV6_IFACE_ADDR);
114	SYS(fail, "ip neigh add %s dev veth1 nud failed", IPV6_NUD_FAILED_ADDR);
115	SYS(fail, "ip neigh add %s dev veth1 lladdr %s nud stale", IPV6_NUD_STALE_ADDR, DMAC);
116
117	SYS(fail, "ip addr add %s/24 dev veth1", IPV4_IFACE_ADDR);
118	SYS(fail, "ip neigh add %s dev veth1 nud failed", IPV4_NUD_FAILED_ADDR);
119	SYS(fail, "ip neigh add %s dev veth1 lladdr %s nud stale", IPV4_NUD_STALE_ADDR, DMAC);
120
121	/* Setup for prefsrc IP addr selection */
122	SYS(fail, "ip addr add %s/24 dev veth1", IPV4_IFACE_ADDR_SEC);
123	SYS(fail, "ip route add %s/32 dev veth1 src %s", IPV4_ADDR_DST, IPV4_IFACE_ADDR_SEC);
124
125	SYS(fail, "ip addr add %s/64 dev veth1 nodad", IPV6_IFACE_ADDR_SEC);
126	SYS(fail, "ip route add %s/128 dev veth1 src %s", IPV6_ADDR_DST, IPV6_IFACE_ADDR_SEC);
127
128	/* Setup for tbid lookup tests */
129	SYS(fail, "ip addr add %s/24 dev veth2", IPV4_TBID_ADDR);
130	SYS(fail, "ip route del %s/24 dev veth2", IPV4_TBID_NET);
131	SYS(fail, "ip route add table 100 %s/24 dev veth2", IPV4_TBID_NET);
132	SYS(fail, "ip neigh add %s dev veth2 lladdr %s nud stale", IPV4_TBID_DST, DMAC2);
133
134	SYS(fail, "ip addr add %s/64 dev veth2", IPV6_TBID_ADDR);
135	SYS(fail, "ip -6 route del %s/64 dev veth2", IPV6_TBID_NET);
136	SYS(fail, "ip -6 route add table 100 %s/64 dev veth2", IPV6_TBID_NET);
137	SYS(fail, "ip neigh add %s dev veth2 lladdr %s nud stale", IPV6_TBID_DST, DMAC2);
138
139	err = write_sysctl("/proc/sys/net/ipv4/conf/veth1/forwarding", "1");
140	if (!ASSERT_OK(err, "write_sysctl(net.ipv4.conf.veth1.forwarding)"))
141		goto fail;
142
143	err = write_sysctl("/proc/sys/net/ipv6/conf/veth1/forwarding", "1");
144	if (!ASSERT_OK(err, "write_sysctl(net.ipv6.conf.veth1.forwarding)"))
145		goto fail;
146
147	return 0;
148fail:
149	return -1;
150}
151
152static int set_lookup_params(struct bpf_fib_lookup *params, const struct fib_lookup_test *test)
153{
154	int ret;
155
156	memset(params, 0, sizeof(*params));
157
158	params->l4_protocol = IPPROTO_TCP;
159	params->ifindex = ifindex;
160	params->tbid = test->tbid;
161
162	if (inet_pton(AF_INET6, test->daddr, params->ipv6_dst) == 1) {
163		params->family = AF_INET6;
164		if (!(test->lookup_flags & BPF_FIB_LOOKUP_SRC)) {
165			ret = inet_pton(AF_INET6, IPV6_IFACE_ADDR, params->ipv6_src);
166			if (!ASSERT_EQ(ret, 1, "inet_pton(IPV6_IFACE_ADDR)"))
167				return -1;
168		}
169
170		return 0;
171	}
172
173	ret = inet_pton(AF_INET, test->daddr, &params->ipv4_dst);
174	if (!ASSERT_EQ(ret, 1, "convert IP[46] address"))
175		return -1;
176	params->family = AF_INET;
177
178	if (!(test->lookup_flags & BPF_FIB_LOOKUP_SRC)) {
179		ret = inet_pton(AF_INET, IPV4_IFACE_ADDR, &params->ipv4_src);
180		if (!ASSERT_EQ(ret, 1, "inet_pton(IPV4_IFACE_ADDR)"))
181			return -1;
182	}
183
184	return 0;
185}
186
187static void mac_str(char *b, const __u8 *mac)
188{
189	sprintf(b, "%02X:%02X:%02X:%02X:%02X:%02X",
190		mac[0], mac[1], mac[2], mac[3], mac[4], mac[5]);
191}
192
193static void assert_src_ip(struct bpf_fib_lookup *fib_params, const char *expected_src)
194{
195	int ret;
196	__u32 src6[4];
197	__be32 src4;
198
199	switch (fib_params->family) {
200	case AF_INET6:
201		ret = inet_pton(AF_INET6, expected_src, src6);
202		ASSERT_EQ(ret, 1, "inet_pton(expected_src)");
203
204		ret = memcmp(src6, fib_params->ipv6_src, sizeof(fib_params->ipv6_src));
205		if (!ASSERT_EQ(ret, 0, "fib_lookup ipv6 src")) {
206			char str_src6[64];
207
208			inet_ntop(AF_INET6, fib_params->ipv6_src, str_src6,
209				  sizeof(str_src6));
210			printf("ipv6 expected %s actual %s ", expected_src,
211			       str_src6);
212		}
213
214		break;
215	case AF_INET:
216		ret = inet_pton(AF_INET, expected_src, &src4);
217		ASSERT_EQ(ret, 1, "inet_pton(expected_src)");
218
219		ASSERT_EQ(fib_params->ipv4_src, src4, "fib_lookup ipv4 src");
220
221		break;
222	default:
223		PRINT_FAIL("invalid addr family: %d", fib_params->family);
224	}
225}
226
227void test_fib_lookup(void)
228{
229	struct bpf_fib_lookup *fib_params;
230	struct nstoken *nstoken = NULL;
231	struct __sk_buff skb = { };
232	struct fib_lookup *skel;
233	int prog_fd, err, ret, i;
234
235	/* The test does not use the skb->data, so
236	 * use pkt_v6 for both v6 and v4 test.
237	 */
238	LIBBPF_OPTS(bpf_test_run_opts, run_opts,
239		    .data_in = &pkt_v6,
240		    .data_size_in = sizeof(pkt_v6),
241		    .ctx_in = &skb,
242		    .ctx_size_in = sizeof(skb),
243	);
244
245	skel = fib_lookup__open_and_load();
246	if (!ASSERT_OK_PTR(skel, "skel open_and_load"))
247		return;
248	prog_fd = bpf_program__fd(skel->progs.fib_lookup);
249
250	SYS(fail, "ip netns add %s", NS_TEST);
251
252	nstoken = open_netns(NS_TEST);
253	if (!ASSERT_OK_PTR(nstoken, "open_netns"))
254		goto fail;
255
256	if (setup_netns())
257		goto fail;
258
259	ifindex = if_nametoindex("veth1");
260	skb.ifindex = ifindex;
261	fib_params = &skel->bss->fib_params;
262
263	for (i = 0; i < ARRAY_SIZE(tests); i++) {
264		printf("Testing %s ", tests[i].desc);
265
266		if (set_lookup_params(fib_params, &tests[i]))
267			continue;
268		skel->bss->fib_lookup_ret = -1;
269		skel->bss->lookup_flags = tests[i].lookup_flags;
270
271		err = bpf_prog_test_run_opts(prog_fd, &run_opts);
272		if (!ASSERT_OK(err, "bpf_prog_test_run_opts"))
273			continue;
274
275		ASSERT_EQ(skel->bss->fib_lookup_ret, tests[i].expected_ret,
276			  "fib_lookup_ret");
277
278		if (tests[i].expected_src)
279			assert_src_ip(fib_params, tests[i].expected_src);
280
281		ret = memcmp(tests[i].dmac, fib_params->dmac, sizeof(tests[i].dmac));
282		if (!ASSERT_EQ(ret, 0, "dmac not match")) {
283			char expected[18], actual[18];
284
285			mac_str(expected, tests[i].dmac);
286			mac_str(actual, fib_params->dmac);
287			printf("dmac expected %s actual %s ", expected, actual);
288		}
289
290		// ensure tbid is zero'd out after fib lookup.
291		if (tests[i].lookup_flags & BPF_FIB_LOOKUP_DIRECT) {
292			if (!ASSERT_EQ(skel->bss->fib_params.tbid, 0,
293					"expected fib_params.tbid to be zero"))
294				goto fail;
295		}
296	}
297
298fail:
299	if (nstoken)
300		close_netns(nstoken);
301	SYS_NOFAIL("ip netns del " NS_TEST);
302	fib_lookup__destroy(skel);
303}
304