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_NUD_FAILED_ADDR	"face::1"
15 #define IPV6_NUD_STALE_ADDR	"face::2"
16 #define IPV4_IFACE_ADDR		"10.0.0.254"
17 #define IPV4_NUD_FAILED_ADDR	"10.0.0.1"
18 #define IPV4_NUD_STALE_ADDR	"10.0.0.2"
19 #define IPV4_TBID_ADDR		"172.0.0.254"
20 #define IPV4_TBID_NET		"172.0.0.0"
21 #define IPV4_TBID_DST		"172.0.0.2"
22 #define IPV6_TBID_ADDR		"fd00::FFFF"
23 #define IPV6_TBID_NET		"fd00::"
24 #define IPV6_TBID_DST		"fd00::2"
25 #define DMAC			"11:11:11:11:11:11"
26 #define DMAC_INIT { 0x11, 0x11, 0x11, 0x11, 0x11, 0x11, }
27 #define DMAC2			"01:01:01:01:01:01"
28 #define DMAC_INIT2 { 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, }
29 
30 struct fib_lookup_test {
31 	const char *desc;
32 	const char *daddr;
33 	int expected_ret;
34 	int lookup_flags;
35 	__u32 tbid;
36 	__u8 dmac[6];
37 };
38 
39 static const struct fib_lookup_test tests[] = {
40 	{ .desc = "IPv6 failed neigh",
41 	  .daddr = IPV6_NUD_FAILED_ADDR, .expected_ret = BPF_FIB_LKUP_RET_NO_NEIGH, },
42 	{ .desc = "IPv6 stale neigh",
43 	  .daddr = IPV6_NUD_STALE_ADDR, .expected_ret = BPF_FIB_LKUP_RET_SUCCESS,
44 	  .dmac = DMAC_INIT, },
45 	{ .desc = "IPv6 skip neigh",
46 	  .daddr = IPV6_NUD_FAILED_ADDR, .expected_ret = BPF_FIB_LKUP_RET_SUCCESS,
47 	  .lookup_flags = BPF_FIB_LOOKUP_SKIP_NEIGH, },
48 	{ .desc = "IPv4 failed neigh",
49 	  .daddr = IPV4_NUD_FAILED_ADDR, .expected_ret = BPF_FIB_LKUP_RET_NO_NEIGH, },
50 	{ .desc = "IPv4 stale neigh",
51 	  .daddr = IPV4_NUD_STALE_ADDR, .expected_ret = BPF_FIB_LKUP_RET_SUCCESS,
52 	  .dmac = DMAC_INIT, },
53 	{ .desc = "IPv4 skip neigh",
54 	  .daddr = IPV4_NUD_FAILED_ADDR, .expected_ret = BPF_FIB_LKUP_RET_SUCCESS,
55 	  .lookup_flags = BPF_FIB_LOOKUP_SKIP_NEIGH, },
56 	{ .desc = "IPv4 TBID lookup failure",
57 	  .daddr = IPV4_TBID_DST, .expected_ret = BPF_FIB_LKUP_RET_NOT_FWDED,
58 	  .lookup_flags = BPF_FIB_LOOKUP_DIRECT | BPF_FIB_LOOKUP_TBID,
59 	  .tbid = RT_TABLE_MAIN, },
60 	{ .desc = "IPv4 TBID lookup success",
61 	  .daddr = IPV4_TBID_DST, .expected_ret = BPF_FIB_LKUP_RET_SUCCESS,
62 	  .lookup_flags = BPF_FIB_LOOKUP_DIRECT | BPF_FIB_LOOKUP_TBID, .tbid = 100,
63 	  .dmac = DMAC_INIT2, },
64 	{ .desc = "IPv6 TBID lookup failure",
65 	  .daddr = IPV6_TBID_DST, .expected_ret = BPF_FIB_LKUP_RET_NOT_FWDED,
66 	  .lookup_flags = BPF_FIB_LOOKUP_DIRECT | BPF_FIB_LOOKUP_TBID,
67 	  .tbid = RT_TABLE_MAIN, },
68 	{ .desc = "IPv6 TBID lookup success",
69 	  .daddr = IPV6_TBID_DST, .expected_ret = BPF_FIB_LKUP_RET_SUCCESS,
70 	  .lookup_flags = BPF_FIB_LOOKUP_DIRECT | BPF_FIB_LOOKUP_TBID, .tbid = 100,
71 	  .dmac = DMAC_INIT2, },
72 };
73 
74 static int ifindex;
75 
setup_netns(void)76 static int setup_netns(void)
77 {
78 	int err;
79 
80 	SYS(fail, "ip link add veth1 type veth peer name veth2");
81 	SYS(fail, "ip link set dev veth1 up");
82 	SYS(fail, "ip link set dev veth2 up");
83 
84 	err = write_sysctl("/proc/sys/net/ipv4/neigh/veth1/gc_stale_time", "900");
85 	if (!ASSERT_OK(err, "write_sysctl(net.ipv4.neigh.veth1.gc_stale_time)"))
86 		goto fail;
87 
88 	err = write_sysctl("/proc/sys/net/ipv6/neigh/veth1/gc_stale_time", "900");
89 	if (!ASSERT_OK(err, "write_sysctl(net.ipv6.neigh.veth1.gc_stale_time)"))
90 		goto fail;
91 
92 	SYS(fail, "ip addr add %s/64 dev veth1 nodad", IPV6_IFACE_ADDR);
93 	SYS(fail, "ip neigh add %s dev veth1 nud failed", IPV6_NUD_FAILED_ADDR);
94 	SYS(fail, "ip neigh add %s dev veth1 lladdr %s nud stale", IPV6_NUD_STALE_ADDR, DMAC);
95 
96 	SYS(fail, "ip addr add %s/24 dev veth1", IPV4_IFACE_ADDR);
97 	SYS(fail, "ip neigh add %s dev veth1 nud failed", IPV4_NUD_FAILED_ADDR);
98 	SYS(fail, "ip neigh add %s dev veth1 lladdr %s nud stale", IPV4_NUD_STALE_ADDR, DMAC);
99 
100 	/* Setup for tbid lookup tests */
101 	SYS(fail, "ip addr add %s/24 dev veth2", IPV4_TBID_ADDR);
102 	SYS(fail, "ip route del %s/24 dev veth2", IPV4_TBID_NET);
103 	SYS(fail, "ip route add table 100 %s/24 dev veth2", IPV4_TBID_NET);
104 	SYS(fail, "ip neigh add %s dev veth2 lladdr %s nud stale", IPV4_TBID_DST, DMAC2);
105 
106 	SYS(fail, "ip addr add %s/64 dev veth2", IPV6_TBID_ADDR);
107 	SYS(fail, "ip -6 route del %s/64 dev veth2", IPV6_TBID_NET);
108 	SYS(fail, "ip -6 route add table 100 %s/64 dev veth2", IPV6_TBID_NET);
109 	SYS(fail, "ip neigh add %s dev veth2 lladdr %s nud stale", IPV6_TBID_DST, DMAC2);
110 
111 	err = write_sysctl("/proc/sys/net/ipv4/conf/veth1/forwarding", "1");
112 	if (!ASSERT_OK(err, "write_sysctl(net.ipv4.conf.veth1.forwarding)"))
113 		goto fail;
114 
115 	err = write_sysctl("/proc/sys/net/ipv6/conf/veth1/forwarding", "1");
116 	if (!ASSERT_OK(err, "write_sysctl(net.ipv6.conf.veth1.forwarding)"))
117 		goto fail;
118 
119 	return 0;
120 fail:
121 	return -1;
122 }
123 
set_lookup_params(struct bpf_fib_lookup * params,const struct fib_lookup_test * test)124 static int set_lookup_params(struct bpf_fib_lookup *params, const struct fib_lookup_test *test)
125 {
126 	int ret;
127 
128 	memset(params, 0, sizeof(*params));
129 
130 	params->l4_protocol = IPPROTO_TCP;
131 	params->ifindex = ifindex;
132 	params->tbid = test->tbid;
133 
134 	if (inet_pton(AF_INET6, test->daddr, params->ipv6_dst) == 1) {
135 		params->family = AF_INET6;
136 		ret = inet_pton(AF_INET6, IPV6_IFACE_ADDR, params->ipv6_src);
137 		if (!ASSERT_EQ(ret, 1, "inet_pton(IPV6_IFACE_ADDR)"))
138 			return -1;
139 		return 0;
140 	}
141 
142 	ret = inet_pton(AF_INET, test->daddr, &params->ipv4_dst);
143 	if (!ASSERT_EQ(ret, 1, "convert IP[46] address"))
144 		return -1;
145 	params->family = AF_INET;
146 	ret = inet_pton(AF_INET, IPV4_IFACE_ADDR, &params->ipv4_src);
147 	if (!ASSERT_EQ(ret, 1, "inet_pton(IPV4_IFACE_ADDR)"))
148 		return -1;
149 
150 	return 0;
151 }
152 
mac_str(char * b,const __u8 * mac)153 static void mac_str(char *b, const __u8 *mac)
154 {
155 	sprintf(b, "%02X:%02X:%02X:%02X:%02X:%02X",
156 		mac[0], mac[1], mac[2], mac[3], mac[4], mac[5]);
157 }
158 
test_fib_lookup(void)159 void test_fib_lookup(void)
160 {
161 	struct bpf_fib_lookup *fib_params;
162 	struct nstoken *nstoken = NULL;
163 	struct __sk_buff skb = { };
164 	struct fib_lookup *skel;
165 	int prog_fd, err, ret, i;
166 
167 	/* The test does not use the skb->data, so
168 	 * use pkt_v6 for both v6 and v4 test.
169 	 */
170 	LIBBPF_OPTS(bpf_test_run_opts, run_opts,
171 		    .data_in = &pkt_v6,
172 		    .data_size_in = sizeof(pkt_v6),
173 		    .ctx_in = &skb,
174 		    .ctx_size_in = sizeof(skb),
175 	);
176 
177 	skel = fib_lookup__open_and_load();
178 	if (!ASSERT_OK_PTR(skel, "skel open_and_load"))
179 		return;
180 	prog_fd = bpf_program__fd(skel->progs.fib_lookup);
181 
182 	SYS(fail, "ip netns add %s", NS_TEST);
183 
184 	nstoken = open_netns(NS_TEST);
185 	if (!ASSERT_OK_PTR(nstoken, "open_netns"))
186 		goto fail;
187 
188 	if (setup_netns())
189 		goto fail;
190 
191 	ifindex = if_nametoindex("veth1");
192 	skb.ifindex = ifindex;
193 	fib_params = &skel->bss->fib_params;
194 
195 	for (i = 0; i < ARRAY_SIZE(tests); i++) {
196 		printf("Testing %s ", tests[i].desc);
197 
198 		if (set_lookup_params(fib_params, &tests[i]))
199 			continue;
200 		skel->bss->fib_lookup_ret = -1;
201 		skel->bss->lookup_flags = tests[i].lookup_flags;
202 
203 		err = bpf_prog_test_run_opts(prog_fd, &run_opts);
204 		if (!ASSERT_OK(err, "bpf_prog_test_run_opts"))
205 			continue;
206 
207 		ASSERT_EQ(skel->bss->fib_lookup_ret, tests[i].expected_ret,
208 			  "fib_lookup_ret");
209 
210 		ret = memcmp(tests[i].dmac, fib_params->dmac, sizeof(tests[i].dmac));
211 		if (!ASSERT_EQ(ret, 0, "dmac not match")) {
212 			char expected[18], actual[18];
213 
214 			mac_str(expected, tests[i].dmac);
215 			mac_str(actual, fib_params->dmac);
216 			printf("dmac expected %s actual %s ", expected, actual);
217 		}
218 
219 		// ensure tbid is zero'd out after fib lookup.
220 		if (tests[i].lookup_flags & BPF_FIB_LOOKUP_DIRECT) {
221 			if (!ASSERT_EQ(skel->bss->fib_params.tbid, 0,
222 					"expected fib_params.tbid to be zero"))
223 				goto fail;
224 		}
225 	}
226 
227 fail:
228 	if (nstoken)
229 		close_netns(nstoken);
230 	SYS_NOFAIL("ip netns del " NS_TEST " &> /dev/null");
231 	fib_lookup__destroy(skel);
232 }
233