xref: /linux/tools/testing/selftests/bpf/prog_tests/xdp_adjust_tail.c (revision 260f6f4fda93c8485c8037865c941b42b9cba5d2)
1 // SPDX-License-Identifier: GPL-2.0
2 #include <test_progs.h>
3 #include <network_helpers.h>
4 
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 
40 static void test_xdp_adjust_tail_grow(bool is_64k_pagesize)
41 {
42 	const char *file = "./test_xdp_adjust_tail_grow.bpf.o";
43 	struct bpf_object *obj;
44 	char buf[8192]; /* 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_out = buf,
50 		.data_size_out = sizeof(buf),
51 		.repeat = 1,
52 	);
53 
54 	/* topts.data_size_in as a special signal to bpf prog */
55 	if (is_64k_pagesize)
56 		topts.data_size_in = sizeof(pkt_v4) - 1;
57 	else
58 		topts.data_size_in = sizeof(pkt_v4);
59 
60 	err = bpf_prog_test_load(file, BPF_PROG_TYPE_XDP, &obj, &prog_fd);
61 	if (!ASSERT_OK(err, "test_xdp_adjust_tail_grow"))
62 		return;
63 
64 	err = bpf_prog_test_run_opts(prog_fd, &topts);
65 	ASSERT_OK(err, "ipv4");
66 	ASSERT_EQ(topts.retval, XDP_DROP, "ipv4 retval");
67 
68 	expect_sz = sizeof(pkt_v6) + 40; /* Test grow with 40 bytes */
69 	topts.data_in = &pkt_v6;
70 	topts.data_size_in = sizeof(pkt_v6);
71 	topts.data_size_out = sizeof(buf);
72 	err = bpf_prog_test_run_opts(prog_fd, &topts);
73 	ASSERT_OK(err, "ipv6");
74 	ASSERT_EQ(topts.retval, XDP_TX, "ipv6 retval");
75 	ASSERT_EQ(topts.data_size_out, expect_sz, "ipv6 size");
76 
77 	bpf_object__close(obj);
78 }
79 
80 static void test_xdp_adjust_tail_grow2(void)
81 {
82 	const char *file = "./test_xdp_adjust_tail_grow.bpf.o";
83 	char buf[4096]; /* avoid segfault: large buf to hold grow results */
84 	struct bpf_object *obj;
85 	int err, cnt, i;
86 	int max_grow, prog_fd;
87 	/* SKB_DATA_ALIGN(sizeof(struct skb_shared_info)) */
88 #if defined(__s390x__)
89 	int tailroom = 512;
90 #elif defined(__powerpc__)
91 	int tailroom = 384;
92 #else
93 	int tailroom = 320;
94 #endif
95 
96 	LIBBPF_OPTS(bpf_test_run_opts, tattr,
97 		.repeat		= 1,
98 		.data_in	= &buf,
99 		.data_out	= &buf,
100 		.data_size_in	= 0, /* Per test */
101 		.data_size_out	= 0, /* Per test */
102 	);
103 
104 	err = bpf_prog_test_load(file, BPF_PROG_TYPE_XDP, &obj, &prog_fd);
105 	if (!ASSERT_OK(err, "test_xdp_adjust_tail_grow"))
106 		return;
107 
108 	/* Test case-64 */
109 	memset(buf, 1, sizeof(buf));
110 	tattr.data_size_in  =  64; /* Determine test case via pkt size */
111 	tattr.data_size_out = 128; /* Limit copy_size */
112 	/* Kernel side alloc packet memory area that is zero init */
113 	err = bpf_prog_test_run_opts(prog_fd, &tattr);
114 
115 	ASSERT_EQ(errno, ENOSPC, "case-64 errno"); /* Due limit copy_size in bpf_test_finish */
116 	ASSERT_EQ(tattr.retval, XDP_TX, "case-64 retval");
117 	ASSERT_EQ(tattr.data_size_out, 192, "case-64 data_size_out"); /* Expected grow size */
118 
119 	/* Extra checks for data contents */
120 	ASSERT_EQ(buf[0], 1, "case-64-data buf[0]"); /*  0-63  memset to 1 */
121 	ASSERT_EQ(buf[63], 1, "case-64-data buf[63]");
122 	ASSERT_EQ(buf[64], 0, "case-64-data buf[64]"); /* 64-127 memset to 0 */
123 	ASSERT_EQ(buf[127], 0, "case-64-data buf[127]");
124 	ASSERT_EQ(buf[128], 1, "case-64-data buf[128]"); /* 128-191 memset to 1 */
125 	ASSERT_EQ(buf[191], 1, "case-64-data buf[191]");
126 
127 	/* Test case-128 */
128 	memset(buf, 2, sizeof(buf));
129 	tattr.data_size_in  = 128; /* Determine test case via pkt size */
130 	tattr.data_size_out = sizeof(buf);   /* Copy everything */
131 	err = bpf_prog_test_run_opts(prog_fd, &tattr);
132 
133 	max_grow = 4096 - XDP_PACKET_HEADROOM -	tailroom; /* 3520 */
134 	ASSERT_OK(err, "case-128");
135 	ASSERT_EQ(tattr.retval, XDP_TX, "case-128 retval");
136 	ASSERT_EQ(tattr.data_size_out, max_grow, "case-128 data_size_out"); /* Expect max grow */
137 
138 	/* Extra checks for data content: Count grow size, will contain zeros */
139 	for (i = 0, cnt = 0; i < sizeof(buf); i++) {
140 		if (buf[i] == 0)
141 			cnt++;
142 	}
143 	ASSERT_EQ(cnt, max_grow - tattr.data_size_in, "case-128-data cnt"); /* Grow increase */
144 	ASSERT_EQ(tattr.data_size_out, max_grow, "case-128-data data_size_out"); /* Total grow */
145 
146 	bpf_object__close(obj);
147 }
148 
149 static void test_xdp_adjust_frags_tail_shrink(void)
150 {
151 	const char *file = "./test_xdp_adjust_tail_shrink.bpf.o";
152 	__u32 exp_size;
153 	struct bpf_program *prog;
154 	struct bpf_object *obj;
155 	int err, prog_fd;
156 	__u8 *buf;
157 	LIBBPF_OPTS(bpf_test_run_opts, topts);
158 
159 	/* For the individual test cases, the first byte in the packet
160 	 * indicates which test will be run.
161 	 */
162 	obj = bpf_object__open(file);
163 	if (libbpf_get_error(obj))
164 		return;
165 
166 	prog = bpf_object__next_program(obj, NULL);
167 	if (bpf_object__load(obj))
168 		return;
169 
170 	prog_fd = bpf_program__fd(prog);
171 
172 	buf = malloc(9000);
173 	if (!ASSERT_OK_PTR(buf, "alloc buf 9Kb"))
174 		goto out;
175 
176 	memset(buf, 0, 9000);
177 
178 	/* Test case removing 10 bytes from last frag, NOT freeing it */
179 	exp_size = 8990; /* 9000 - 10 */
180 	topts.data_in = buf;
181 	topts.data_out = buf;
182 	topts.data_size_in = 9000;
183 	topts.data_size_out = 9000;
184 	err = bpf_prog_test_run_opts(prog_fd, &topts);
185 
186 	ASSERT_OK(err, "9Kb-10b");
187 	ASSERT_EQ(topts.retval, XDP_TX, "9Kb-10b retval");
188 	ASSERT_EQ(topts.data_size_out, exp_size, "9Kb-10b size");
189 
190 	/* Test case removing one of two pages, assuming 4K pages */
191 	buf[0] = 1;
192 	exp_size = 4900; /* 9000 - 4100 */
193 
194 	topts.data_size_out = 9000; /* reset from previous invocation */
195 	err = bpf_prog_test_run_opts(prog_fd, &topts);
196 
197 	ASSERT_OK(err, "9Kb-4Kb");
198 	ASSERT_EQ(topts.retval, XDP_TX, "9Kb-4Kb retval");
199 	ASSERT_EQ(topts.data_size_out, exp_size, "9Kb-4Kb size");
200 
201 	/* Test case removing two pages resulting in a linear xdp_buff */
202 	buf[0] = 2;
203 	exp_size = 800; /* 9000 - 8200 */
204 	topts.data_size_out = 9000; /* reset from previous invocation */
205 	err = bpf_prog_test_run_opts(prog_fd, &topts);
206 
207 	ASSERT_OK(err, "9Kb-9Kb");
208 	ASSERT_EQ(topts.retval, XDP_TX, "9Kb-9Kb retval");
209 	ASSERT_EQ(topts.data_size_out, exp_size, "9Kb-9Kb size");
210 
211 	free(buf);
212 out:
213 	bpf_object__close(obj);
214 }
215 
216 static void test_xdp_adjust_frags_tail_grow_4k(void)
217 {
218 	const char *file = "./test_xdp_adjust_tail_grow.bpf.o";
219 	__u32 exp_size;
220 	struct bpf_program *prog;
221 	struct bpf_object *obj;
222 	int err, i, prog_fd;
223 	__u8 *buf;
224 	LIBBPF_OPTS(bpf_test_run_opts, topts);
225 
226 	obj = bpf_object__open(file);
227 	if (libbpf_get_error(obj))
228 		return;
229 
230 	prog = bpf_object__next_program(obj, NULL);
231 	if (bpf_object__load(obj))
232 		goto out;
233 
234 	prog_fd = bpf_program__fd(prog);
235 
236 	buf = malloc(16384);
237 	if (!ASSERT_OK_PTR(buf, "alloc buf 16Kb"))
238 		goto out;
239 
240 	/* Test case add 10 bytes to last frag */
241 	memset(buf, 1, 16384);
242 	exp_size = 9000 + 10;
243 
244 	topts.data_in = buf;
245 	topts.data_out = buf;
246 	topts.data_size_in = 9000;
247 	topts.data_size_out = 16384;
248 	err = bpf_prog_test_run_opts(prog_fd, &topts);
249 
250 	ASSERT_OK(err, "9Kb+10b");
251 	ASSERT_EQ(topts.retval, XDP_TX, "9Kb+10b retval");
252 	ASSERT_EQ(topts.data_size_out, exp_size, "9Kb+10b size");
253 
254 	for (i = 0; i < 9000; i++) {
255 		if (buf[i] != 1)
256 			ASSERT_EQ(buf[i], 1, "9Kb+10b-old");
257 	}
258 
259 	for (i = 9000; i < 9010; i++) {
260 		if (buf[i] != 0)
261 			ASSERT_EQ(buf[i], 0, "9Kb+10b-new");
262 	}
263 
264 	for (i = 9010; i < 16384; i++) {
265 		if (buf[i] != 1)
266 			ASSERT_EQ(buf[i], 1, "9Kb+10b-untouched");
267 	}
268 
269 	/* Test a too large grow */
270 	memset(buf, 1, 16384);
271 	exp_size = 9001;
272 
273 	topts.data_in = topts.data_out = buf;
274 	topts.data_size_in = 9001;
275 	topts.data_size_out = 16384;
276 	err = bpf_prog_test_run_opts(prog_fd, &topts);
277 
278 	ASSERT_OK(err, "9Kb+10b");
279 	ASSERT_EQ(topts.retval, XDP_DROP, "9Kb+10b retval");
280 	ASSERT_EQ(topts.data_size_out, exp_size, "9Kb+10b size");
281 
282 	free(buf);
283 out:
284 	bpf_object__close(obj);
285 }
286 
287 static void test_xdp_adjust_frags_tail_grow_64k(void)
288 {
289 	const char *file = "./test_xdp_adjust_tail_grow.bpf.o";
290 	__u32 exp_size;
291 	struct bpf_program *prog;
292 	struct bpf_object *obj;
293 	int err, i, prog_fd;
294 	__u8 *buf;
295 	LIBBPF_OPTS(bpf_test_run_opts, topts);
296 
297 	obj = bpf_object__open(file);
298 	if (libbpf_get_error(obj))
299 		return;
300 
301 	prog = bpf_object__next_program(obj, NULL);
302 	if (bpf_object__load(obj))
303 		goto out;
304 
305 	prog_fd = bpf_program__fd(prog);
306 
307 	buf = malloc(262144);
308 	if (!ASSERT_OK_PTR(buf, "alloc buf 256Kb"))
309 		goto out;
310 
311 	/* Test case add 10 bytes to last frag */
312 	memset(buf, 1, 262144);
313 	exp_size = 90000 + 10;
314 
315 	topts.data_in = buf;
316 	topts.data_out = buf;
317 	topts.data_size_in = 90000;
318 	topts.data_size_out = 262144;
319 	err = bpf_prog_test_run_opts(prog_fd, &topts);
320 
321 	ASSERT_OK(err, "90Kb+10b");
322 	ASSERT_EQ(topts.retval, XDP_TX, "90Kb+10b retval");
323 	ASSERT_EQ(topts.data_size_out, exp_size, "90Kb+10b size");
324 
325 	for (i = 0; i < 90000; i++) {
326 		if (buf[i] != 1)
327 			ASSERT_EQ(buf[i], 1, "90Kb+10b-old");
328 	}
329 
330 	for (i = 90000; i < 90010; i++) {
331 		if (buf[i] != 0)
332 			ASSERT_EQ(buf[i], 0, "90Kb+10b-new");
333 	}
334 
335 	for (i = 90010; i < 262144; i++) {
336 		if (buf[i] != 1)
337 			ASSERT_EQ(buf[i], 1, "90Kb+10b-untouched");
338 	}
339 
340 	/* Test a too large grow */
341 	memset(buf, 1, 262144);
342 	exp_size = 90001;
343 
344 	topts.data_in = topts.data_out = buf;
345 	topts.data_size_in = 90001;
346 	topts.data_size_out = 262144;
347 	err = bpf_prog_test_run_opts(prog_fd, &topts);
348 
349 	ASSERT_OK(err, "90Kb+10b");
350 	ASSERT_EQ(topts.retval, XDP_DROP, "90Kb+10b retval");
351 	ASSERT_EQ(topts.data_size_out, exp_size, "90Kb+10b size");
352 
353 	free(buf);
354 out:
355 	bpf_object__close(obj);
356 }
357 
358 void test_xdp_adjust_tail(void)
359 {
360 	int page_size = getpagesize();
361 
362 	if (test__start_subtest("xdp_adjust_tail_shrink"))
363 		test_xdp_adjust_tail_shrink();
364 	if (test__start_subtest("xdp_adjust_tail_grow"))
365 		test_xdp_adjust_tail_grow(page_size == 65536);
366 	if (test__start_subtest("xdp_adjust_tail_grow2"))
367 		test_xdp_adjust_tail_grow2();
368 	if (test__start_subtest("xdp_adjust_frags_tail_shrink"))
369 		test_xdp_adjust_frags_tail_shrink();
370 	if (test__start_subtest("xdp_adjust_frags_tail_grow")) {
371 		if (page_size == 65536)
372 			test_xdp_adjust_frags_tail_grow_64k();
373 		else
374 			test_xdp_adjust_frags_tail_grow_4k();
375 	}
376 }
377