xref: /openbmc/linux/lib/test_bpf.c (revision 64a8946b)
1 /*
2  * Testsuite for BPF interpreter and BPF JIT compiler
3  *
4  * Copyright (c) 2011-2014 PLUMgrid, http://plumgrid.com
5  *
6  * This program is free software; you can redistribute it and/or
7  * modify it under the terms of version 2 of the GNU General Public
8  * License as published by the Free Software Foundation.
9  *
10  * This program is distributed in the hope that it will be useful, but
11  * WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13  * General Public License for more details.
14  */
15 
16 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
17 
18 #include <linux/init.h>
19 #include <linux/module.h>
20 #include <linux/filter.h>
21 #include <linux/skbuff.h>
22 #include <linux/netdevice.h>
23 #include <linux/if_vlan.h>
24 
25 #define MAX_SUBTESTS	3
26 #define MAX_DATA	128
27 #define MAX_INSNS	512
28 #define MAX_K		0xffffFFFF
29 
30 /* define few constants used to init test 'skb' */
31 #define SKB_TYPE	3
32 #define SKB_MARK	0x1234aaaa
33 #define SKB_HASH	0x1234aaab
34 #define SKB_QUEUE_MAP	123
35 #define SKB_VLAN_TCI	0xffff
36 #define SKB_DEV_IFINDEX	577
37 #define SKB_DEV_TYPE	588
38 
39 /* redefine REGs to make tests less verbose */
40 #define R0 BPF_REG_0
41 #define R1 BPF_REG_1
42 #define R2 BPF_REG_2
43 #define R3 BPF_REG_3
44 #define R4 BPF_REG_4
45 #define R5 BPF_REG_5
46 #define R6 BPF_REG_6
47 #define R7 BPF_REG_7
48 #define R8 BPF_REG_8
49 #define R9 BPF_REG_9
50 #define R10 BPF_REG_10
51 
52 struct bpf_test {
53 	const char *descr;
54 	union {
55 		struct sock_filter insns[MAX_INSNS];
56 		struct sock_filter_int insns_int[MAX_INSNS];
57 	};
58 	enum {
59 		NO_DATA,
60 		EXPECTED_FAIL,
61 		SKB,
62 		SKB_INT
63 	} data_type;
64 	__u8 data[MAX_DATA];
65 	struct {
66 		int data_size;
67 		__u32 result;
68 	} test[MAX_SUBTESTS];
69 };
70 
71 static struct bpf_test tests[] = {
72 	{
73 		"TAX",
74 		.insns = {
75 			BPF_STMT(BPF_LD | BPF_IMM, 1),
76 			BPF_STMT(BPF_MISC | BPF_TAX, 0),
77 			BPF_STMT(BPF_LD | BPF_IMM, 2),
78 			BPF_STMT(BPF_ALU | BPF_ADD | BPF_X, 0),
79 			BPF_STMT(BPF_ALU | BPF_NEG, 0), /* A == -3 */
80 			BPF_STMT(BPF_MISC | BPF_TAX, 0),
81 			BPF_STMT(BPF_LD | BPF_LEN, 0),
82 			BPF_STMT(BPF_ALU | BPF_ADD | BPF_X, 0),
83 			BPF_STMT(BPF_MISC | BPF_TAX, 0), /* X == len - 3 */
84 			BPF_STMT(BPF_LD | BPF_B | BPF_IND, 1),
85 			BPF_STMT(BPF_RET | BPF_A, 0)
86 		},
87 		SKB,
88 		{ 10, 20, 30, 40, 50 },
89 		{ { 2, 10 }, { 3, 20 }, { 4, 30 } },
90 	},
91 	{
92 		"tcpdump port 22",
93 		.insns = {
94 			{ 0x28,  0,  0, 0x0000000c },
95 			{ 0x15,  0,  8, 0x000086dd },
96 			{ 0x30,  0,  0, 0x00000014 },
97 			{ 0x15,  2,  0, 0x00000084 },
98 			{ 0x15,  1,  0, 0x00000006 },
99 			{ 0x15,  0, 17, 0x00000011 },
100 			{ 0x28,  0,  0, 0x00000036 },
101 			{ 0x15, 14,  0, 0x00000016 },
102 			{ 0x28,  0,  0, 0x00000038 },
103 			{ 0x15, 12, 13, 0x00000016 },
104 			{ 0x15,  0, 12, 0x00000800 },
105 			{ 0x30,  0,  0, 0x00000017 },
106 			{ 0x15,  2,  0, 0x00000084 },
107 			{ 0x15,  1,  0, 0x00000006 },
108 			{ 0x15,  0,  8, 0x00000011 },
109 			{ 0x28,  0,  0, 0x00000014 },
110 			{ 0x45,  6,  0, 0x00001fff },
111 			{ 0xb1,  0,  0, 0x0000000e },
112 			{ 0x48,  0,  0, 0x0000000e },
113 			{ 0x15,  2,  0, 0x00000016 },
114 			{ 0x48,  0,  0, 0x00000010 },
115 			{ 0x15,  0,  1, 0x00000016 },
116 			{ 0x06,  0,  0, 0x0000ffff },
117 			{ 0x06,  0,  0, 0x00000000 },
118 		},
119 		SKB,
120 		/* 3c:07:54:43:e5:76 > 10:bf:48:d6:43:d6, ethertype IPv4(0x0800)
121 		 * length 114: 10.1.1.149.49700 > 10.1.2.10.22: Flags [P.],
122 		 * seq 1305692979:1305693027, ack 3650467037, win 65535,
123 		 * options [nop,nop,TS val 2502645400 ecr 3971138], length 48
124 		 */
125 		{ 0x10, 0xbf, 0x48, 0xd6, 0x43, 0xd6,
126 		  0x3c, 0x07, 0x54, 0x43, 0xe5, 0x76,
127 		  0x08, 0x00,
128 		  0x45, 0x10, 0x00, 0x64, 0x75, 0xb5,
129 		  0x40, 0x00, 0x40, 0x06, 0xad, 0x2e, /* IP header */
130 		  0x0a, 0x01, 0x01, 0x95, /* ip src */
131 		  0x0a, 0x01, 0x02, 0x0a, /* ip dst */
132 		  0xc2, 0x24,
133 		  0x00, 0x16 /* dst port */ },
134 		{ { 10, 0 }, { 30, 0 }, { 100, 65535 } },
135 	},
136 	{
137 		"INT: DIV + ABS",
138 		.insns_int = {
139 			BPF_ALU64_REG(BPF_MOV, R6, R1),
140 			BPF_LD_ABS(BPF_B, 3),
141 			BPF_ALU64_IMM(BPF_MOV, R2, 2),
142 			BPF_ALU32_REG(BPF_DIV, R0, R2),
143 			BPF_ALU64_REG(BPF_MOV, R8, R0),
144 			BPF_LD_ABS(BPF_B, 4),
145 			BPF_ALU64_REG(BPF_ADD, R8, R0),
146 			BPF_LD_IND(BPF_B, R8, -70),
147 			BPF_EXIT_INSN(),
148 		},
149 		SKB_INT,
150 		{ 10, 20, 30, 40, 50 },
151 		{ { 4, 0 }, { 5, 10 } }
152 	},
153 	{
154 		"check: missing ret",
155 		.insns = {
156 			BPF_STMT(BPF_LD | BPF_IMM, 1),
157 		},
158 		EXPECTED_FAIL,
159 		{ },
160 		{ }
161 	},
162 };
163 
164 static int get_length(struct sock_filter *fp)
165 {
166 	int len = 0;
167 
168 	while (fp->code != 0 || fp->k != 0) {
169 		fp++;
170 		len++;
171 	}
172 
173 	return len;
174 }
175 
176 struct net_device dev;
177 struct sk_buff *populate_skb(char *buf, int size)
178 {
179 	struct sk_buff *skb;
180 
181 	if (size >= MAX_DATA)
182 		return NULL;
183 
184 	skb = alloc_skb(MAX_DATA, GFP_KERNEL);
185 	if (!skb)
186 		return NULL;
187 
188 	memcpy(__skb_put(skb, size), buf, size);
189 	skb_reset_mac_header(skb);
190 	skb->protocol = htons(ETH_P_IP);
191 	skb->pkt_type = SKB_TYPE;
192 	skb->mark = SKB_MARK;
193 	skb->hash = SKB_HASH;
194 	skb->queue_mapping = SKB_QUEUE_MAP;
195 	skb->vlan_tci = SKB_VLAN_TCI;
196 	skb->dev = &dev;
197 	skb->dev->ifindex = SKB_DEV_IFINDEX;
198 	skb->dev->type = SKB_DEV_TYPE;
199 	skb_set_network_header(skb, min(size, ETH_HLEN));
200 
201 	return skb;
202 }
203 
204 static int run_one(struct sk_filter *fp, struct bpf_test *t)
205 {
206 	u64 start, finish, res, cnt = 100000;
207 	int err_cnt = 0, err, i, j;
208 	u32 ret = 0;
209 	void *data;
210 
211 	for (i = 0; i < MAX_SUBTESTS; i++) {
212 		if (t->test[i].data_size == 0 &&
213 		    t->test[i].result == 0)
214 			break;
215 		if (t->data_type == SKB ||
216 		    t->data_type == SKB_INT) {
217 			data = populate_skb(t->data, t->test[i].data_size);
218 			if (!data)
219 				return -ENOMEM;
220 		} else {
221 			data = NULL;
222 		}
223 
224 		start = ktime_to_us(ktime_get());
225 		for (j = 0; j < cnt; j++)
226 			ret = SK_RUN_FILTER(fp, data);
227 		finish = ktime_to_us(ktime_get());
228 
229 		res = (finish - start) * 1000;
230 		do_div(res, cnt);
231 
232 		err = ret != t->test[i].result;
233 		if (!err)
234 			pr_cont("%lld ", res);
235 
236 		if (t->data_type == SKB || t->data_type == SKB_INT)
237 			kfree_skb(data);
238 
239 		if (err) {
240 			pr_cont("ret %d != %d ", ret, t->test[i].result);
241 			err_cnt++;
242 		}
243 	}
244 
245 	return err_cnt;
246 }
247 
248 static __init int test_bpf(void)
249 {
250 	struct sk_filter *fp, *fp_ext = NULL;
251 	struct sock_fprog fprog;
252 	int err, i, err_cnt = 0;
253 
254 	for (i = 0; i < ARRAY_SIZE(tests); i++) {
255 		pr_info("#%d %s ", i, tests[i].descr);
256 
257 		fprog.filter = tests[i].insns;
258 		fprog.len = get_length(fprog.filter);
259 
260 		if (tests[i].data_type == SKB_INT) {
261 			fp_ext = kzalloc(4096, GFP_KERNEL);
262 			if (!fp_ext)
263 				return -ENOMEM;
264 			fp = fp_ext;
265 			memcpy(fp_ext->insns, tests[i].insns_int,
266 			       fprog.len * 8);
267 			fp->len = fprog.len;
268 			fp->bpf_func = sk_run_filter_int_skb;
269 		} else {
270 			err = sk_unattached_filter_create(&fp, &fprog);
271 			if (tests[i].data_type == EXPECTED_FAIL) {
272 				if (err == -EINVAL) {
273 					pr_cont("PASS\n");
274 					continue;
275 				} else {
276 					pr_cont("UNEXPECTED_PASS\n");
277 					/* verifier didn't reject the test
278 					 * that's bad enough, just return
279 					 */
280 					return -EINVAL;
281 				}
282 			}
283 			if (err) {
284 				pr_cont("FAIL to attach err=%d len=%d\n",
285 					err, fprog.len);
286 				return err;
287 			}
288 		}
289 
290 		err = run_one(fp, &tests[i]);
291 
292 		if (tests[i].data_type != SKB_INT)
293 			sk_unattached_filter_destroy(fp);
294 		else
295 			kfree(fp);
296 
297 		if (err) {
298 			pr_cont("FAIL %d\n", err);
299 			err_cnt++;
300 		} else {
301 			pr_cont("PASS\n");
302 		}
303 	}
304 
305 	if (err_cnt)
306 		return -EINVAL;
307 	else
308 		return 0;
309 }
310 
311 static int __init test_bpf_init(void)
312 {
313 	return test_bpf();
314 }
315 
316 static void __exit test_bpf_exit(void)
317 {
318 }
319 
320 module_init(test_bpf_init);
321 module_exit(test_bpf_exit);
322 MODULE_LICENSE("GPL");
323