xref: /linux/tools/testing/selftests/bpf/prog_tests/xdp_adjust_tail.c (revision d0d106a2bd21499901299160744e5fe9f4c83ddb)
1 // SPDX-License-Identifier: GPL-2.0
2 #include <test_progs.h>
3 #include <network_helpers.h>
4 
test_xdp_adjust_tail_shrink(void)5 static void test_xdp_adjust_tail_shrink(void)
6 {
7 	const char *file = "./test_xdp_adjust_tail_shrink.bpf.o";
8 	__u32 expect_sz;
9 	struct bpf_object *obj;
10 	int err, prog_fd;
11 	char buf[128];
12 	LIBBPF_OPTS(bpf_test_run_opts, topts,
13 		.data_in = &pkt_v4,
14 		.data_size_in = sizeof(pkt_v4),
15 		.data_out = buf,
16 		.data_size_out = sizeof(buf),
17 		.repeat = 1,
18 	);
19 
20 	err = bpf_prog_test_load(file, BPF_PROG_TYPE_XDP, &obj, &prog_fd);
21 	if (!ASSERT_OK(err, "test_xdp_adjust_tail_shrink"))
22 		return;
23 
24 	err = bpf_prog_test_run_opts(prog_fd, &topts);
25 	ASSERT_OK(err, "ipv4");
26 	ASSERT_EQ(topts.retval, XDP_DROP, "ipv4 retval");
27 
28 	expect_sz = sizeof(pkt_v6) - 20;  /* Test shrink with 20 bytes */
29 	topts.data_in = &pkt_v6;
30 	topts.data_size_in = sizeof(pkt_v6);
31 	topts.data_size_out = sizeof(buf);
32 	err = bpf_prog_test_run_opts(prog_fd, &topts);
33 	ASSERT_OK(err, "ipv6");
34 	ASSERT_EQ(topts.retval, XDP_TX, "ipv6 retval");
35 	ASSERT_EQ(topts.data_size_out, expect_sz, "ipv6 size");
36 
37 	bpf_object__close(obj);
38 }
39 
test_xdp_adjust_tail_grow(void)40 static void test_xdp_adjust_tail_grow(void)
41 {
42 	const char *file = "./test_xdp_adjust_tail_grow.bpf.o";
43 	struct bpf_object *obj;
44 	char buf[4096]; /* avoid segfault: large buf to hold grow results */
45 	__u32 expect_sz;
46 	int err, prog_fd;
47 	LIBBPF_OPTS(bpf_test_run_opts, topts,
48 		.data_in = &pkt_v4,
49 		.data_size_in = sizeof(pkt_v4),
50 		.data_out = buf,
51 		.data_size_out = sizeof(buf),
52 		.repeat = 1,
53 	);
54 
55 	err = bpf_prog_test_load(file, BPF_PROG_TYPE_XDP, &obj, &prog_fd);
56 	if (!ASSERT_OK(err, "test_xdp_adjust_tail_grow"))
57 		return;
58 
59 	err = bpf_prog_test_run_opts(prog_fd, &topts);
60 	ASSERT_OK(err, "ipv4");
61 	ASSERT_EQ(topts.retval, XDP_DROP, "ipv4 retval");
62 
63 	expect_sz = sizeof(pkt_v6) + 40; /* Test grow with 40 bytes */
64 	topts.data_in = &pkt_v6;
65 	topts.data_size_in = sizeof(pkt_v6);
66 	topts.data_size_out = sizeof(buf);
67 	err = bpf_prog_test_run_opts(prog_fd, &topts);
68 	ASSERT_OK(err, "ipv6");
69 	ASSERT_EQ(topts.retval, XDP_TX, "ipv6 retval");
70 	ASSERT_EQ(topts.data_size_out, expect_sz, "ipv6 size");
71 
72 	bpf_object__close(obj);
73 }
74 
test_xdp_adjust_tail_grow2(void)75 static void test_xdp_adjust_tail_grow2(void)
76 {
77 	const char *file = "./test_xdp_adjust_tail_grow.bpf.o";
78 	char buf[4096]; /* avoid segfault: large buf to hold grow results */
79 	struct bpf_object *obj;
80 	int err, cnt, i;
81 	int max_grow, prog_fd;
82 	/* SKB_DATA_ALIGN(sizeof(struct skb_shared_info)) */
83 #if defined(__s390x__)
84 	int tailroom = 512;
85 #elif defined(__powerpc__)
86 	int tailroom = 384;
87 #else
88 	int tailroom = 320;
89 #endif
90 
91 	LIBBPF_OPTS(bpf_test_run_opts, tattr,
92 		.repeat		= 1,
93 		.data_in	= &buf,
94 		.data_out	= &buf,
95 		.data_size_in	= 0, /* Per test */
96 		.data_size_out	= 0, /* Per test */
97 	);
98 
99 	err = bpf_prog_test_load(file, BPF_PROG_TYPE_XDP, &obj, &prog_fd);
100 	if (!ASSERT_OK(err, "test_xdp_adjust_tail_grow"))
101 		return;
102 
103 	/* Test case-64 */
104 	memset(buf, 1, sizeof(buf));
105 	tattr.data_size_in  =  64; /* Determine test case via pkt size */
106 	tattr.data_size_out = 128; /* Limit copy_size */
107 	/* Kernel side alloc packet memory area that is zero init */
108 	err = bpf_prog_test_run_opts(prog_fd, &tattr);
109 
110 	ASSERT_EQ(errno, ENOSPC, "case-64 errno"); /* Due limit copy_size in bpf_test_finish */
111 	ASSERT_EQ(tattr.retval, XDP_TX, "case-64 retval");
112 	ASSERT_EQ(tattr.data_size_out, 192, "case-64 data_size_out"); /* Expected grow size */
113 
114 	/* Extra checks for data contents */
115 	ASSERT_EQ(buf[0], 1, "case-64-data buf[0]"); /*  0-63  memset to 1 */
116 	ASSERT_EQ(buf[63], 1, "case-64-data buf[63]");
117 	ASSERT_EQ(buf[64], 0, "case-64-data buf[64]"); /* 64-127 memset to 0 */
118 	ASSERT_EQ(buf[127], 0, "case-64-data buf[127]");
119 	ASSERT_EQ(buf[128], 1, "case-64-data buf[128]"); /* 128-191 memset to 1 */
120 	ASSERT_EQ(buf[191], 1, "case-64-data buf[191]");
121 
122 	/* Test case-128 */
123 	memset(buf, 2, sizeof(buf));
124 	tattr.data_size_in  = 128; /* Determine test case via pkt size */
125 	tattr.data_size_out = sizeof(buf);   /* Copy everything */
126 	err = bpf_prog_test_run_opts(prog_fd, &tattr);
127 
128 	max_grow = 4096 - XDP_PACKET_HEADROOM -	tailroom; /* 3520 */
129 	ASSERT_OK(err, "case-128");
130 	ASSERT_EQ(tattr.retval, XDP_TX, "case-128 retval");
131 	ASSERT_EQ(tattr.data_size_out, max_grow, "case-128 data_size_out"); /* Expect max grow */
132 
133 	/* Extra checks for data content: Count grow size, will contain zeros */
134 	for (i = 0, cnt = 0; i < sizeof(buf); i++) {
135 		if (buf[i] == 0)
136 			cnt++;
137 	}
138 	ASSERT_EQ(cnt, max_grow - tattr.data_size_in, "case-128-data cnt"); /* Grow increase */
139 	ASSERT_EQ(tattr.data_size_out, max_grow, "case-128-data data_size_out"); /* Total grow */
140 
141 	bpf_object__close(obj);
142 }
143 
test_xdp_adjust_frags_tail_shrink(void)144 static void test_xdp_adjust_frags_tail_shrink(void)
145 {
146 	const char *file = "./test_xdp_adjust_tail_shrink.bpf.o";
147 	__u32 exp_size;
148 	struct bpf_program *prog;
149 	struct bpf_object *obj;
150 	int err, prog_fd;
151 	__u8 *buf;
152 	LIBBPF_OPTS(bpf_test_run_opts, topts);
153 
154 	/* For the individual test cases, the first byte in the packet
155 	 * indicates which test will be run.
156 	 */
157 	obj = bpf_object__open(file);
158 	if (libbpf_get_error(obj))
159 		return;
160 
161 	prog = bpf_object__next_program(obj, NULL);
162 	if (bpf_object__load(obj))
163 		return;
164 
165 	prog_fd = bpf_program__fd(prog);
166 
167 	buf = malloc(9000);
168 	if (!ASSERT_OK_PTR(buf, "alloc buf 9Kb"))
169 		goto out;
170 
171 	memset(buf, 0, 9000);
172 
173 	/* Test case removing 10 bytes from last frag, NOT freeing it */
174 	exp_size = 8990; /* 9000 - 10 */
175 	topts.data_in = buf;
176 	topts.data_out = buf;
177 	topts.data_size_in = 9000;
178 	topts.data_size_out = 9000;
179 	err = bpf_prog_test_run_opts(prog_fd, &topts);
180 
181 	ASSERT_OK(err, "9Kb-10b");
182 	ASSERT_EQ(topts.retval, XDP_TX, "9Kb-10b retval");
183 	ASSERT_EQ(topts.data_size_out, exp_size, "9Kb-10b size");
184 
185 	/* Test case removing one of two pages, assuming 4K pages */
186 	buf[0] = 1;
187 	exp_size = 4900; /* 9000 - 4100 */
188 
189 	topts.data_size_out = 9000; /* reset from previous invocation */
190 	err = bpf_prog_test_run_opts(prog_fd, &topts);
191 
192 	ASSERT_OK(err, "9Kb-4Kb");
193 	ASSERT_EQ(topts.retval, XDP_TX, "9Kb-4Kb retval");
194 	ASSERT_EQ(topts.data_size_out, exp_size, "9Kb-4Kb size");
195 
196 	/* Test case removing two pages resulting in a linear xdp_buff */
197 	buf[0] = 2;
198 	exp_size = 800; /* 9000 - 8200 */
199 	topts.data_size_out = 9000; /* reset from previous invocation */
200 	err = bpf_prog_test_run_opts(prog_fd, &topts);
201 
202 	ASSERT_OK(err, "9Kb-9Kb");
203 	ASSERT_EQ(topts.retval, XDP_TX, "9Kb-9Kb retval");
204 	ASSERT_EQ(topts.data_size_out, exp_size, "9Kb-9Kb size");
205 
206 	free(buf);
207 out:
208 	bpf_object__close(obj);
209 }
210 
test_xdp_adjust_frags_tail_grow(void)211 static void test_xdp_adjust_frags_tail_grow(void)
212 {
213 	const char *file = "./test_xdp_adjust_tail_grow.bpf.o";
214 	__u32 exp_size;
215 	struct bpf_program *prog;
216 	struct bpf_object *obj;
217 	int err, i, prog_fd;
218 	__u8 *buf;
219 	LIBBPF_OPTS(bpf_test_run_opts, topts);
220 
221 	obj = bpf_object__open(file);
222 	if (libbpf_get_error(obj))
223 		return;
224 
225 	prog = bpf_object__next_program(obj, NULL);
226 	if (bpf_object__load(obj))
227 		goto out;
228 
229 	prog_fd = bpf_program__fd(prog);
230 
231 	buf = malloc(16384);
232 	if (!ASSERT_OK_PTR(buf, "alloc buf 16Kb"))
233 		goto out;
234 
235 	/* Test case add 10 bytes to last frag */
236 	memset(buf, 1, 16384);
237 	exp_size = 9000 + 10;
238 
239 	topts.data_in = buf;
240 	topts.data_out = buf;
241 	topts.data_size_in = 9000;
242 	topts.data_size_out = 16384;
243 	err = bpf_prog_test_run_opts(prog_fd, &topts);
244 
245 	ASSERT_OK(err, "9Kb+10b");
246 	ASSERT_EQ(topts.retval, XDP_TX, "9Kb+10b retval");
247 	ASSERT_EQ(topts.data_size_out, exp_size, "9Kb+10b size");
248 
249 	for (i = 0; i < 9000; i++)
250 		ASSERT_EQ(buf[i], 1, "9Kb+10b-old");
251 
252 	for (i = 9000; i < 9010; i++)
253 		ASSERT_EQ(buf[i], 0, "9Kb+10b-new");
254 
255 	for (i = 9010; i < 16384; i++)
256 		ASSERT_EQ(buf[i], 1, "9Kb+10b-untouched");
257 
258 	/* Test a too large grow */
259 	memset(buf, 1, 16384);
260 	exp_size = 9001;
261 
262 	topts.data_in = topts.data_out = buf;
263 	topts.data_size_in = 9001;
264 	topts.data_size_out = 16384;
265 	err = bpf_prog_test_run_opts(prog_fd, &topts);
266 
267 	ASSERT_OK(err, "9Kb+10b");
268 	ASSERT_EQ(topts.retval, XDP_DROP, "9Kb+10b retval");
269 	ASSERT_EQ(topts.data_size_out, exp_size, "9Kb+10b size");
270 
271 	free(buf);
272 out:
273 	bpf_object__close(obj);
274 }
275 
test_xdp_adjust_tail(void)276 void test_xdp_adjust_tail(void)
277 {
278 	if (test__start_subtest("xdp_adjust_tail_shrink"))
279 		test_xdp_adjust_tail_shrink();
280 	if (test__start_subtest("xdp_adjust_tail_grow"))
281 		test_xdp_adjust_tail_grow();
282 	if (test__start_subtest("xdp_adjust_tail_grow2"))
283 		test_xdp_adjust_tail_grow2();
284 	if (test__start_subtest("xdp_adjust_frags_tail_shrink"))
285 		test_xdp_adjust_frags_tail_shrink();
286 	if (test__start_subtest("xdp_adjust_frags_tail_grow"))
287 		test_xdp_adjust_frags_tail_grow();
288 }
289