xref: /linux/net/core/net_test.c (revision 3f41368fbfe1b3d5922d317fe1a0a0cab6846802)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 
3 #include <kunit/test.h>
4 
5 /* GSO */
6 
7 #include <linux/skbuff.h>
8 
9 static const char hdr[] = "abcdefgh";
10 #define GSO_TEST_SIZE 1000
11 
12 static void __init_skb(struct sk_buff *skb)
13 {
14 	skb_reset_mac_header(skb);
15 	memcpy(skb_mac_header(skb), hdr, sizeof(hdr));
16 
17 	/* skb_segment expects skb->data at start of payload */
18 	skb_pull(skb, sizeof(hdr));
19 	skb_reset_network_header(skb);
20 	skb_reset_transport_header(skb);
21 
22 	/* proto is arbitrary, as long as not ETH_P_TEB or vlan */
23 	skb->protocol = htons(ETH_P_ATALK);
24 	skb_shinfo(skb)->gso_size = GSO_TEST_SIZE;
25 }
26 
27 enum gso_test_nr {
28 	GSO_TEST_LINEAR,
29 	GSO_TEST_NO_GSO,
30 	GSO_TEST_FRAGS,
31 	GSO_TEST_FRAGS_PURE,
32 	GSO_TEST_GSO_PARTIAL,
33 	GSO_TEST_FRAG_LIST,
34 	GSO_TEST_FRAG_LIST_PURE,
35 	GSO_TEST_FRAG_LIST_NON_UNIFORM,
36 	GSO_TEST_GSO_BY_FRAGS,
37 };
38 
39 struct gso_test_case {
40 	enum gso_test_nr id;
41 	const char *name;
42 
43 	/* input */
44 	unsigned int linear_len;
45 	unsigned int nr_frags;
46 	const unsigned int *frags;
47 	unsigned int nr_frag_skbs;
48 	const unsigned int *frag_skbs;
49 
50 	/* output as expected */
51 	unsigned int nr_segs;
52 	const unsigned int *segs;
53 };
54 
55 static struct gso_test_case cases[] = {
56 	{
57 		.id = GSO_TEST_NO_GSO,
58 		.name = "no_gso",
59 		.linear_len = GSO_TEST_SIZE,
60 		.nr_segs = 1,
61 		.segs = (const unsigned int[]) { GSO_TEST_SIZE },
62 	},
63 	{
64 		.id = GSO_TEST_LINEAR,
65 		.name = "linear",
66 		.linear_len = GSO_TEST_SIZE + GSO_TEST_SIZE + 1,
67 		.nr_segs = 3,
68 		.segs = (const unsigned int[]) { GSO_TEST_SIZE, GSO_TEST_SIZE, 1 },
69 	},
70 	{
71 		.id = GSO_TEST_FRAGS,
72 		.name = "frags",
73 		.linear_len = GSO_TEST_SIZE,
74 		.nr_frags = 2,
75 		.frags = (const unsigned int[]) { GSO_TEST_SIZE, 1 },
76 		.nr_segs = 3,
77 		.segs = (const unsigned int[]) { GSO_TEST_SIZE, GSO_TEST_SIZE, 1 },
78 	},
79 	{
80 		.id = GSO_TEST_FRAGS_PURE,
81 		.name = "frags_pure",
82 		.nr_frags = 3,
83 		.frags = (const unsigned int[]) { GSO_TEST_SIZE, GSO_TEST_SIZE, 2 },
84 		.nr_segs = 3,
85 		.segs = (const unsigned int[]) { GSO_TEST_SIZE, GSO_TEST_SIZE, 2 },
86 	},
87 	{
88 		.id = GSO_TEST_GSO_PARTIAL,
89 		.name = "gso_partial",
90 		.linear_len = GSO_TEST_SIZE,
91 		.nr_frags = 2,
92 		.frags = (const unsigned int[]) { GSO_TEST_SIZE, 3 },
93 		.nr_segs = 2,
94 		.segs = (const unsigned int[]) { 2 * GSO_TEST_SIZE, 3 },
95 	},
96 	{
97 		/* commit 89319d3801d1: frag_list on mss boundaries */
98 		.id = GSO_TEST_FRAG_LIST,
99 		.name = "frag_list",
100 		.linear_len = GSO_TEST_SIZE,
101 		.nr_frag_skbs = 2,
102 		.frag_skbs = (const unsigned int[]) { GSO_TEST_SIZE, GSO_TEST_SIZE },
103 		.nr_segs = 3,
104 		.segs = (const unsigned int[]) { GSO_TEST_SIZE, GSO_TEST_SIZE, GSO_TEST_SIZE },
105 	},
106 	{
107 		.id = GSO_TEST_FRAG_LIST_PURE,
108 		.name = "frag_list_pure",
109 		.nr_frag_skbs = 2,
110 		.frag_skbs = (const unsigned int[]) { GSO_TEST_SIZE, GSO_TEST_SIZE },
111 		.nr_segs = 2,
112 		.segs = (const unsigned int[]) { GSO_TEST_SIZE, GSO_TEST_SIZE },
113 	},
114 	{
115 		/* commit 43170c4e0ba7: GRO of frag_list trains */
116 		.id = GSO_TEST_FRAG_LIST_NON_UNIFORM,
117 		.name = "frag_list_non_uniform",
118 		.linear_len = GSO_TEST_SIZE,
119 		.nr_frag_skbs = 4,
120 		.frag_skbs = (const unsigned int[]) { GSO_TEST_SIZE, 1, GSO_TEST_SIZE, 2 },
121 		.nr_segs = 4,
122 		.segs = (const unsigned int[]) { GSO_TEST_SIZE, GSO_TEST_SIZE, GSO_TEST_SIZE, 3 },
123 	},
124 	{
125 		/* commit 3953c46c3ac7 ("sk_buff: allow segmenting based on frag sizes") and
126 		 * commit 90017accff61 ("sctp: Add GSO support")
127 		 *
128 		 * "there will be a cover skb with protocol headers and
129 		 *  children ones containing the actual segments"
130 		 */
131 		.id = GSO_TEST_GSO_BY_FRAGS,
132 		.name = "gso_by_frags",
133 		.nr_frag_skbs = 4,
134 		.frag_skbs = (const unsigned int[]) { 100, 200, 300, 400 },
135 		.nr_segs = 4,
136 		.segs = (const unsigned int[]) { 100, 200, 300, 400 },
137 	},
138 };
139 
140 static void gso_test_case_to_desc(struct gso_test_case *t, char *desc)
141 {
142 	sprintf(desc, "%s", t->name);
143 }
144 
145 KUNIT_ARRAY_PARAM(gso_test, cases, gso_test_case_to_desc);
146 
147 static void gso_test_func(struct kunit *test)
148 {
149 	const int shinfo_size = SKB_DATA_ALIGN(sizeof(struct skb_shared_info));
150 	struct sk_buff *skb, *segs, *cur, *next, *last;
151 	const struct gso_test_case *tcase;
152 	netdev_features_t features;
153 	struct page *page;
154 	int i;
155 
156 	tcase = test->param_value;
157 
158 	page = alloc_page(GFP_KERNEL);
159 	KUNIT_ASSERT_NOT_NULL(test, page);
160 	skb = build_skb(page_address(page), sizeof(hdr) + tcase->linear_len + shinfo_size);
161 	KUNIT_ASSERT_NOT_NULL(test, skb);
162 	__skb_put(skb, sizeof(hdr) + tcase->linear_len);
163 
164 	__init_skb(skb);
165 
166 	if (tcase->nr_frags) {
167 		unsigned int pg_off = 0;
168 
169 		page = alloc_page(GFP_KERNEL);
170 		KUNIT_ASSERT_NOT_NULL(test, page);
171 		page_ref_add(page, tcase->nr_frags - 1);
172 
173 		for (i = 0; i < tcase->nr_frags; i++) {
174 			skb_fill_page_desc(skb, i, page, pg_off, tcase->frags[i]);
175 			pg_off += tcase->frags[i];
176 		}
177 
178 		KUNIT_ASSERT_LE(test, pg_off, PAGE_SIZE);
179 
180 		skb->data_len = pg_off;
181 		skb->len += skb->data_len;
182 		skb->truesize += skb->data_len;
183 	}
184 
185 	if (tcase->frag_skbs) {
186 		unsigned int total_size = 0, total_true_size = 0;
187 		struct sk_buff *frag_skb, *prev = NULL;
188 
189 		for (i = 0; i < tcase->nr_frag_skbs; i++) {
190 			unsigned int frag_size;
191 
192 			page = alloc_page(GFP_KERNEL);
193 			KUNIT_ASSERT_NOT_NULL(test, page);
194 
195 			frag_size = tcase->frag_skbs[i];
196 			frag_skb = build_skb(page_address(page),
197 					     frag_size + shinfo_size);
198 			KUNIT_ASSERT_NOT_NULL(test, frag_skb);
199 			__skb_put(frag_skb, frag_size);
200 
201 			if (prev)
202 				prev->next = frag_skb;
203 			else
204 				skb_shinfo(skb)->frag_list = frag_skb;
205 			prev = frag_skb;
206 
207 			total_size += frag_size;
208 			total_true_size += frag_skb->truesize;
209 		}
210 
211 		skb->len += total_size;
212 		skb->data_len += total_size;
213 		skb->truesize += total_true_size;
214 
215 		if (tcase->id == GSO_TEST_GSO_BY_FRAGS)
216 			skb_shinfo(skb)->gso_size = GSO_BY_FRAGS;
217 	}
218 
219 	features = NETIF_F_SG | NETIF_F_HW_CSUM;
220 	if (tcase->id == GSO_TEST_GSO_PARTIAL)
221 		features |= NETIF_F_GSO_PARTIAL;
222 
223 	/* TODO: this should also work with SG,
224 	 * rather than hit BUG_ON(i >= nfrags)
225 	 */
226 	if (tcase->id == GSO_TEST_FRAG_LIST_NON_UNIFORM)
227 		features &= ~NETIF_F_SG;
228 
229 	segs = skb_segment(skb, features);
230 	if (IS_ERR(segs)) {
231 		KUNIT_FAIL(test, "segs error %pe", segs);
232 		goto free_gso_skb;
233 	} else if (!segs) {
234 		KUNIT_FAIL(test, "no segments");
235 		goto free_gso_skb;
236 	}
237 
238 	last = segs->prev;
239 	for (cur = segs, i = 0; cur; cur = next, i++) {
240 		next = cur->next;
241 
242 		KUNIT_ASSERT_EQ(test, cur->len, sizeof(hdr) + tcase->segs[i]);
243 
244 		/* segs have skb->data pointing to the mac header */
245 		KUNIT_ASSERT_PTR_EQ(test, skb_mac_header(cur), cur->data);
246 		KUNIT_ASSERT_PTR_EQ(test, skb_network_header(cur), cur->data + sizeof(hdr));
247 
248 		/* header was copied to all segs */
249 		KUNIT_ASSERT_EQ(test, memcmp(skb_mac_header(cur), hdr, sizeof(hdr)), 0);
250 
251 		/* last seg can be found through segs->prev pointer */
252 		if (!next)
253 			KUNIT_ASSERT_PTR_EQ(test, cur, last);
254 
255 		consume_skb(cur);
256 	}
257 
258 	KUNIT_ASSERT_EQ(test, i, tcase->nr_segs);
259 
260 free_gso_skb:
261 	consume_skb(skb);
262 }
263 
264 /* IP tunnel flags */
265 
266 #include <net/ip_tunnels.h>
267 
268 struct ip_tunnel_flags_test {
269 	const char	*name;
270 
271 	const u16	*src_bits;
272 	const u16	*exp_bits;
273 	u8		src_num;
274 	u8		exp_num;
275 
276 	__be16		exp_val;
277 	bool		exp_comp;
278 };
279 
280 #define IP_TUNNEL_FLAGS_TEST(n, src, comp, eval, exp) {	\
281 	.name		= (n),				\
282 	.src_bits	= (src),			\
283 	.src_num	= ARRAY_SIZE(src),		\
284 	.exp_comp	= (comp),			\
285 	.exp_val	= (eval),			\
286 	.exp_bits	= (exp),			\
287 	.exp_num	= ARRAY_SIZE(exp),		\
288 }
289 
290 /* These are __be16-compatible and can be compared as is */
291 static const u16 ip_tunnel_flags_1[] = {
292 	IP_TUNNEL_KEY_BIT,
293 	IP_TUNNEL_STRICT_BIT,
294 	IP_TUNNEL_ERSPAN_OPT_BIT,
295 };
296 
297 /* Due to the previous flags design limitation, setting either
298  * ``IP_TUNNEL_CSUM_BIT`` (on Big Endian) or ``IP_TUNNEL_DONT_FRAGMENT_BIT``
299  * (on Little) also sets VTI/ISATAP bit. In the bitmap implementation, they
300  * correspond to ``BIT(16)``, which is bigger than ``U16_MAX``, but still is
301  * backward-compatible.
302  */
303 #ifdef __LITTLE_ENDIAN
304 #define IP_TUNNEL_CONFLICT_BIT	IP_TUNNEL_DONT_FRAGMENT_BIT
305 #else
306 #define IP_TUNNEL_CONFLICT_BIT	IP_TUNNEL_CSUM_BIT
307 #endif
308 
309 static const u16 ip_tunnel_flags_2_src[] = {
310 	IP_TUNNEL_CONFLICT_BIT,
311 };
312 
313 static const u16 ip_tunnel_flags_2_exp[] = {
314 	IP_TUNNEL_CONFLICT_BIT,
315 	IP_TUNNEL_SIT_ISATAP_BIT,
316 };
317 
318 /* Bits 17 and higher are not compatible with __be16 flags */
319 static const u16 ip_tunnel_flags_3_src[] = {
320 	IP_TUNNEL_VXLAN_OPT_BIT,
321 	17,
322 	18,
323 	20,
324 };
325 
326 static const u16 ip_tunnel_flags_3_exp[] = {
327 	IP_TUNNEL_VXLAN_OPT_BIT,
328 };
329 
330 static const struct ip_tunnel_flags_test ip_tunnel_flags_test[] = {
331 	IP_TUNNEL_FLAGS_TEST("compat", ip_tunnel_flags_1, true,
332 			     cpu_to_be16(BIT(IP_TUNNEL_KEY_BIT) |
333 					 BIT(IP_TUNNEL_STRICT_BIT) |
334 					 BIT(IP_TUNNEL_ERSPAN_OPT_BIT)),
335 			     ip_tunnel_flags_1),
336 	IP_TUNNEL_FLAGS_TEST("conflict", ip_tunnel_flags_2_src, true,
337 			     VTI_ISVTI, ip_tunnel_flags_2_exp),
338 	IP_TUNNEL_FLAGS_TEST("new", ip_tunnel_flags_3_src, false,
339 			     cpu_to_be16(BIT(IP_TUNNEL_VXLAN_OPT_BIT)),
340 			     ip_tunnel_flags_3_exp),
341 };
342 
343 static void
344 ip_tunnel_flags_test_case_to_desc(const struct ip_tunnel_flags_test *t,
345 				  char *desc)
346 {
347 	strscpy(desc, t->name, KUNIT_PARAM_DESC_SIZE);
348 }
349 KUNIT_ARRAY_PARAM(ip_tunnel_flags_test, ip_tunnel_flags_test,
350 		  ip_tunnel_flags_test_case_to_desc);
351 
352 static void ip_tunnel_flags_test_run(struct kunit *test)
353 {
354 	const struct ip_tunnel_flags_test *t = test->param_value;
355 	IP_TUNNEL_DECLARE_FLAGS(src) = { };
356 	IP_TUNNEL_DECLARE_FLAGS(exp) = { };
357 	IP_TUNNEL_DECLARE_FLAGS(out);
358 
359 	for (u32 j = 0; j < t->src_num; j++)
360 		__set_bit(t->src_bits[j], src);
361 	for (u32 j = 0; j < t->exp_num; j++)
362 		__set_bit(t->exp_bits[j], exp);
363 
364 	KUNIT_ASSERT_EQ(test, t->exp_comp,
365 			ip_tunnel_flags_is_be16_compat(src));
366 	KUNIT_ASSERT_EQ(test, (__force u16)t->exp_val,
367 			(__force u16)ip_tunnel_flags_to_be16(src));
368 
369 	ip_tunnel_flags_from_be16(out, t->exp_val);
370 	KUNIT_ASSERT_TRUE(test, __ipt_flag_op(bitmap_equal, exp, out));
371 }
372 
373 static struct kunit_case net_test_cases[] = {
374 	KUNIT_CASE_PARAM(gso_test_func, gso_test_gen_params),
375 	KUNIT_CASE_PARAM(ip_tunnel_flags_test_run,
376 			 ip_tunnel_flags_test_gen_params),
377 	{ },
378 };
379 
380 static struct kunit_suite net_test_suite = {
381 	.name		= "net_core",
382 	.test_cases	= net_test_cases,
383 };
384 kunit_test_suite(net_test_suite);
385 
386 MODULE_DESCRIPTION("KUnit tests for networking core");
387 MODULE_LICENSE("GPL");
388