xref: /linux/tools/testing/selftests/net/psock_fanout.c (revision c532de5a67a70f8533d495f8f2aaa9a0491c3ad0)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright 2013 Google Inc.
4  * Author: Willem de Bruijn (willemb@google.com)
5  *
6  * A basic test of packet socket fanout behavior.
7  *
8  * Control:
9  * - create fanout fails as expected with illegal flag combinations
10  * - join   fanout fails as expected with diverging types or flags
11  *
12  * Datapath:
13  *   Open a pair of packet sockets and a pair of INET sockets, send a known
14  *   number of packets across the two INET sockets and count the number of
15  *   packets enqueued onto the two packet sockets.
16  *
17  *   The test currently runs for
18  *   - PACKET_FANOUT_HASH
19  *   - PACKET_FANOUT_HASH with PACKET_FANOUT_FLAG_ROLLOVER
20  *   - PACKET_FANOUT_LB
21  *   - PACKET_FANOUT_CPU
22  *   - PACKET_FANOUT_ROLLOVER
23  *   - PACKET_FANOUT_CBPF
24  *   - PACKET_FANOUT_EBPF
25  *
26  * Todo:
27  * - functionality: PACKET_FANOUT_FLAG_DEFRAG
28  */
29 
30 #define _GNU_SOURCE		/* for sched_setaffinity */
31 
32 #include <arpa/inet.h>
33 #include <errno.h>
34 #include <fcntl.h>
35 #include <linux/unistd.h>	/* for __NR_bpf */
36 #include <linux/filter.h>
37 #include <linux/bpf.h>
38 #include <linux/if_packet.h>
39 #include <net/if.h>
40 #include <net/ethernet.h>
41 #include <netinet/ip.h>
42 #include <netinet/udp.h>
43 #include <poll.h>
44 #include <sched.h>
45 #include <stdint.h>
46 #include <stdio.h>
47 #include <stdlib.h>
48 #include <string.h>
49 #include <sys/mman.h>
50 #include <sys/socket.h>
51 #include <sys/stat.h>
52 #include <sys/types.h>
53 #include <unistd.h>
54 
55 #include "psock_lib.h"
56 #include "../kselftest.h"
57 
58 #define RING_NUM_FRAMES			20
59 
60 static uint32_t cfg_max_num_members;
61 
62 /* Open a socket in a given fanout mode.
63  * @return -1 if mode is bad, a valid socket otherwise */
64 static int sock_fanout_open(uint16_t typeflags, uint16_t group_id)
65 {
66 	struct sockaddr_ll addr = {0};
67 	struct fanout_args args;
68 	int fd, val, err;
69 
70 	fd = socket(PF_PACKET, SOCK_RAW, 0);
71 	if (fd < 0) {
72 		perror("socket packet");
73 		exit(1);
74 	}
75 
76 	pair_udp_setfilter(fd);
77 
78 	addr.sll_family = AF_PACKET;
79 	addr.sll_protocol = htons(ETH_P_IP);
80 	addr.sll_ifindex = if_nametoindex("lo");
81 	if (addr.sll_ifindex == 0) {
82 		perror("if_nametoindex");
83 		exit(1);
84 	}
85 	if (bind(fd, (void *) &addr, sizeof(addr))) {
86 		perror("bind packet");
87 		exit(1);
88 	}
89 
90 	if (cfg_max_num_members) {
91 		args.id = group_id;
92 		args.type_flags = typeflags;
93 		args.max_num_members = cfg_max_num_members;
94 		err = setsockopt(fd, SOL_PACKET, PACKET_FANOUT, &args,
95 				 sizeof(args));
96 	} else {
97 		val = (((int) typeflags) << 16) | group_id;
98 		err = setsockopt(fd, SOL_PACKET, PACKET_FANOUT, &val,
99 				 sizeof(val));
100 	}
101 	if (err) {
102 		if (close(fd)) {
103 			perror("close packet");
104 			exit(1);
105 		}
106 		return -1;
107 	}
108 
109 	return fd;
110 }
111 
112 static void sock_fanout_set_cbpf(int fd)
113 {
114 	struct sock_filter bpf_filter[] = {
115 		BPF_STMT(BPF_LD | BPF_B | BPF_ABS, 80),	      /* ldb [80] */
116 		BPF_STMT(BPF_RET | BPF_A, 0),		      /* ret A */
117 	};
118 	struct sock_fprog bpf_prog;
119 
120 	bpf_prog.filter = bpf_filter;
121 	bpf_prog.len = ARRAY_SIZE(bpf_filter);
122 
123 	if (setsockopt(fd, SOL_PACKET, PACKET_FANOUT_DATA, &bpf_prog,
124 		       sizeof(bpf_prog))) {
125 		perror("fanout data cbpf");
126 		exit(1);
127 	}
128 }
129 
130 static void sock_fanout_getopts(int fd, uint16_t *typeflags, uint16_t *group_id)
131 {
132 	int sockopt;
133 	socklen_t sockopt_len = sizeof(sockopt);
134 
135 	if (getsockopt(fd, SOL_PACKET, PACKET_FANOUT,
136 		       &sockopt, &sockopt_len)) {
137 		perror("failed to getsockopt");
138 		exit(1);
139 	}
140 	*typeflags = sockopt >> 16;
141 	*group_id = sockopt & 0xfffff;
142 }
143 
144 static void sock_fanout_set_ebpf(int fd)
145 {
146 	static char log_buf[65536];
147 
148 	const int len_off = __builtin_offsetof(struct __sk_buff, len);
149 	struct bpf_insn prog[] = {
150 		{ BPF_ALU64 | BPF_MOV | BPF_X,   6, 1, 0, 0 },
151 		{ BPF_LDX   | BPF_W   | BPF_MEM, 0, 6, len_off, 0 },
152 		{ BPF_JMP   | BPF_JGE | BPF_K,   0, 0, 1, DATA_LEN },
153 		{ BPF_JMP   | BPF_JA  | BPF_K,   0, 0, 4, 0 },
154 		{ BPF_LD    | BPF_B   | BPF_ABS, 0, 0, 0, 0x50 },
155 		{ BPF_JMP   | BPF_JEQ | BPF_K,   0, 0, 2, DATA_CHAR },
156 		{ BPF_JMP   | BPF_JEQ | BPF_K,   0, 0, 1, DATA_CHAR_1 },
157 		{ BPF_ALU   | BPF_MOV | BPF_K,   0, 0, 0, 0 },
158 		{ BPF_JMP   | BPF_EXIT,          0, 0, 0, 0 }
159 	};
160 	union bpf_attr attr;
161 	int pfd;
162 
163 	memset(&attr, 0, sizeof(attr));
164 	attr.prog_type = BPF_PROG_TYPE_SOCKET_FILTER;
165 	attr.insns = (unsigned long) prog;
166 	attr.insn_cnt = ARRAY_SIZE(prog);
167 	attr.license = (unsigned long) "GPL";
168 	attr.log_buf = (unsigned long) log_buf;
169 	attr.log_size = sizeof(log_buf);
170 	attr.log_level = 1;
171 
172 	pfd = syscall(__NR_bpf, BPF_PROG_LOAD, &attr, sizeof(attr));
173 	if (pfd < 0) {
174 		perror("bpf");
175 		fprintf(stderr, "bpf verifier:\n%s\n", log_buf);
176 		exit(1);
177 	}
178 
179 	if (setsockopt(fd, SOL_PACKET, PACKET_FANOUT_DATA, &pfd, sizeof(pfd))) {
180 		perror("fanout data ebpf");
181 		exit(1);
182 	}
183 
184 	if (close(pfd)) {
185 		perror("close ebpf");
186 		exit(1);
187 	}
188 }
189 
190 static char *sock_fanout_open_ring(int fd)
191 {
192 	struct tpacket_req req = {
193 		.tp_block_size = getpagesize(),
194 		.tp_frame_size = getpagesize(),
195 		.tp_block_nr   = RING_NUM_FRAMES,
196 		.tp_frame_nr   = RING_NUM_FRAMES,
197 	};
198 	char *ring;
199 	int val = TPACKET_V2;
200 
201 	if (setsockopt(fd, SOL_PACKET, PACKET_VERSION, (void *) &val,
202 		       sizeof(val))) {
203 		perror("packetsock ring setsockopt version");
204 		exit(1);
205 	}
206 	if (setsockopt(fd, SOL_PACKET, PACKET_RX_RING, (void *) &req,
207 		       sizeof(req))) {
208 		perror("packetsock ring setsockopt");
209 		exit(1);
210 	}
211 
212 	ring = mmap(0, req.tp_block_size * req.tp_block_nr,
213 		    PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);
214 	if (ring == MAP_FAILED) {
215 		perror("packetsock ring mmap");
216 		exit(1);
217 	}
218 
219 	return ring;
220 }
221 
222 static int sock_fanout_read_ring(int fd, void *ring)
223 {
224 	struct tpacket2_hdr *header = ring;
225 	int count = 0;
226 
227 	while (count < RING_NUM_FRAMES && header->tp_status & TP_STATUS_USER) {
228 		count++;
229 		header = ring + (count * getpagesize());
230 	}
231 
232 	return count;
233 }
234 
235 static int sock_fanout_read(int fds[], char *rings[], const int expect[])
236 {
237 	int ret[2];
238 
239 	ret[0] = sock_fanout_read_ring(fds[0], rings[0]);
240 	ret[1] = sock_fanout_read_ring(fds[1], rings[1]);
241 
242 	fprintf(stderr, "info: count=%d,%d, expect=%d,%d\n",
243 			ret[0], ret[1], expect[0], expect[1]);
244 
245 	if ((!(ret[0] == expect[0] && ret[1] == expect[1])) &&
246 	    (!(ret[0] == expect[1] && ret[1] == expect[0]))) {
247 		fprintf(stderr, "warning: incorrect queue lengths\n");
248 		return 1;
249 	}
250 
251 	return 0;
252 }
253 
254 /* Test illegal mode + flag combination */
255 static void test_control_single(void)
256 {
257 	fprintf(stderr, "test: control single socket\n");
258 
259 	if (sock_fanout_open(PACKET_FANOUT_ROLLOVER |
260 			       PACKET_FANOUT_FLAG_ROLLOVER, 0) != -1) {
261 		fprintf(stderr, "ERROR: opened socket with dual rollover\n");
262 		exit(1);
263 	}
264 }
265 
266 /* Test illegal group with different modes or flags */
267 static void test_control_group(void)
268 {
269 	int fds[2];
270 
271 	fprintf(stderr, "test: control multiple sockets\n");
272 
273 	fds[0] = sock_fanout_open(PACKET_FANOUT_HASH, 0);
274 	if (fds[0] == -1) {
275 		fprintf(stderr, "ERROR: failed to open HASH socket\n");
276 		exit(1);
277 	}
278 	if (sock_fanout_open(PACKET_FANOUT_HASH |
279 			       PACKET_FANOUT_FLAG_DEFRAG, 0) != -1) {
280 		fprintf(stderr, "ERROR: joined group with wrong flag defrag\n");
281 		exit(1);
282 	}
283 	if (sock_fanout_open(PACKET_FANOUT_HASH |
284 			       PACKET_FANOUT_FLAG_ROLLOVER, 0) != -1) {
285 		fprintf(stderr, "ERROR: joined group with wrong flag ro\n");
286 		exit(1);
287 	}
288 	if (sock_fanout_open(PACKET_FANOUT_CPU, 0) != -1) {
289 		fprintf(stderr, "ERROR: joined group with wrong mode\n");
290 		exit(1);
291 	}
292 	fds[1] = sock_fanout_open(PACKET_FANOUT_HASH, 0);
293 	if (fds[1] == -1) {
294 		fprintf(stderr, "ERROR: failed to join group\n");
295 		exit(1);
296 	}
297 	if (close(fds[1]) || close(fds[0])) {
298 		fprintf(stderr, "ERROR: closing sockets\n");
299 		exit(1);
300 	}
301 }
302 
303 /* Test illegal max_num_members values */
304 static void test_control_group_max_num_members(void)
305 {
306 	int fds[3];
307 
308 	fprintf(stderr, "test: control multiple sockets, max_num_members\n");
309 
310 	/* expected failure on greater than PACKET_FANOUT_MAX */
311 	cfg_max_num_members = (1 << 16) + 1;
312 	if (sock_fanout_open(PACKET_FANOUT_HASH, 0) != -1) {
313 		fprintf(stderr, "ERROR: max_num_members > PACKET_FANOUT_MAX\n");
314 		exit(1);
315 	}
316 
317 	cfg_max_num_members = 256;
318 	fds[0] = sock_fanout_open(PACKET_FANOUT_HASH, 0);
319 	if (fds[0] == -1) {
320 		fprintf(stderr, "ERROR: failed open\n");
321 		exit(1);
322 	}
323 
324 	/* expected failure on joining group with different max_num_members */
325 	cfg_max_num_members = 257;
326 	if (sock_fanout_open(PACKET_FANOUT_HASH, 0) != -1) {
327 		fprintf(stderr, "ERROR: set different max_num_members\n");
328 		exit(1);
329 	}
330 
331 	/* success on joining group with same max_num_members */
332 	cfg_max_num_members = 256;
333 	fds[1] = sock_fanout_open(PACKET_FANOUT_HASH, 0);
334 	if (fds[1] == -1) {
335 		fprintf(stderr, "ERROR: failed to join group\n");
336 		exit(1);
337 	}
338 
339 	/* success on joining group with max_num_members unspecified */
340 	cfg_max_num_members = 0;
341 	fds[2] = sock_fanout_open(PACKET_FANOUT_HASH, 0);
342 	if (fds[2] == -1) {
343 		fprintf(stderr, "ERROR: failed to join group\n");
344 		exit(1);
345 	}
346 
347 	if (close(fds[2]) || close(fds[1]) || close(fds[0])) {
348 		fprintf(stderr, "ERROR: closing sockets\n");
349 		exit(1);
350 	}
351 }
352 
353 /* Test creating a unique fanout group ids */
354 static void test_unique_fanout_group_ids(void)
355 {
356 	int fds[3];
357 	uint16_t typeflags, first_group_id, second_group_id;
358 
359 	fprintf(stderr, "test: unique ids\n");
360 
361 	fds[0] = sock_fanout_open(PACKET_FANOUT_HASH |
362 				  PACKET_FANOUT_FLAG_UNIQUEID, 0);
363 	if (fds[0] == -1) {
364 		fprintf(stderr, "ERROR: failed to create a unique id group.\n");
365 		exit(1);
366 	}
367 
368 	sock_fanout_getopts(fds[0], &typeflags, &first_group_id);
369 	if (typeflags != PACKET_FANOUT_HASH) {
370 		fprintf(stderr, "ERROR: unexpected typeflags %x\n", typeflags);
371 		exit(1);
372 	}
373 
374 	if (sock_fanout_open(PACKET_FANOUT_CPU, first_group_id) != -1) {
375 		fprintf(stderr, "ERROR: joined group with wrong type.\n");
376 		exit(1);
377 	}
378 
379 	fds[1] = sock_fanout_open(PACKET_FANOUT_HASH, first_group_id);
380 	if (fds[1] == -1) {
381 		fprintf(stderr,
382 			"ERROR: failed to join previously created group.\n");
383 		exit(1);
384 	}
385 
386 	fds[2] = sock_fanout_open(PACKET_FANOUT_HASH |
387 				  PACKET_FANOUT_FLAG_UNIQUEID, 0);
388 	if (fds[2] == -1) {
389 		fprintf(stderr,
390 			"ERROR: failed to create a second unique id group.\n");
391 		exit(1);
392 	}
393 
394 	sock_fanout_getopts(fds[2], &typeflags, &second_group_id);
395 	if (sock_fanout_open(PACKET_FANOUT_HASH | PACKET_FANOUT_FLAG_UNIQUEID,
396 			     second_group_id) != -1) {
397 		fprintf(stderr,
398 			"ERROR: specified a group id when requesting unique id\n");
399 		exit(1);
400 	}
401 
402 	if (close(fds[0]) || close(fds[1]) || close(fds[2])) {
403 		fprintf(stderr, "ERROR: closing sockets\n");
404 		exit(1);
405 	}
406 }
407 
408 static int test_datapath(uint16_t typeflags, int port_off,
409 			 const int expect1[], const int expect2[])
410 {
411 	const int expect0[] = { 0, 0 };
412 	char *rings[2];
413 	uint8_t type = typeflags & 0xFF;
414 	int fds[2], fds_udp[2][2], ret;
415 
416 	fprintf(stderr, "\ntest: datapath 0x%hx ports %hu,%hu\n",
417 		typeflags, (uint16_t)PORT_BASE,
418 		(uint16_t)(PORT_BASE + port_off));
419 
420 	fds[0] = sock_fanout_open(typeflags, 0);
421 	fds[1] = sock_fanout_open(typeflags, 0);
422 	if (fds[0] == -1 || fds[1] == -1) {
423 		fprintf(stderr, "ERROR: failed open\n");
424 		exit(1);
425 	}
426 	if (type == PACKET_FANOUT_CBPF)
427 		sock_fanout_set_cbpf(fds[0]);
428 	else if (type == PACKET_FANOUT_EBPF)
429 		sock_fanout_set_ebpf(fds[0]);
430 
431 	rings[0] = sock_fanout_open_ring(fds[0]);
432 	rings[1] = sock_fanout_open_ring(fds[1]);
433 	pair_udp_open(fds_udp[0], PORT_BASE);
434 	pair_udp_open(fds_udp[1], PORT_BASE + port_off);
435 	sock_fanout_read(fds, rings, expect0);
436 
437 	/* Send data, but not enough to overflow a queue */
438 	pair_udp_send(fds_udp[0], 15);
439 	pair_udp_send_char(fds_udp[1], 5, DATA_CHAR_1);
440 	ret = sock_fanout_read(fds, rings, expect1);
441 
442 	/* Send more data, overflow the queue */
443 	pair_udp_send_char(fds_udp[0], 15, DATA_CHAR_1);
444 	/* TODO: ensure consistent order between expect1 and expect2 */
445 	ret |= sock_fanout_read(fds, rings, expect2);
446 
447 	if (munmap(rings[1], RING_NUM_FRAMES * getpagesize()) ||
448 	    munmap(rings[0], RING_NUM_FRAMES * getpagesize())) {
449 		fprintf(stderr, "close rings\n");
450 		exit(1);
451 	}
452 	if (close(fds_udp[1][1]) || close(fds_udp[1][0]) ||
453 	    close(fds_udp[0][1]) || close(fds_udp[0][0]) ||
454 	    close(fds[1]) || close(fds[0])) {
455 		fprintf(stderr, "close datapath\n");
456 		exit(1);
457 	}
458 
459 	return ret;
460 }
461 
462 static int set_cpuaffinity(int cpuid)
463 {
464 	cpu_set_t mask;
465 
466 	CPU_ZERO(&mask);
467 	CPU_SET(cpuid, &mask);
468 	if (sched_setaffinity(0, sizeof(mask), &mask)) {
469 		if (errno != EINVAL) {
470 			fprintf(stderr, "setaffinity %d\n", cpuid);
471 			exit(1);
472 		}
473 		return 1;
474 	}
475 
476 	return 0;
477 }
478 
479 int main(int argc, char **argv)
480 {
481 	const int expect_hash[2][2]	= { { 15, 5 },  { 20, 5 } };
482 	const int expect_hash_rb[2][2]	= { { 15, 5 },  { 20, 15 } };
483 	const int expect_lb[2][2]	= { { 10, 10 }, { 18, 17 } };
484 	const int expect_rb[2][2]	= { { 15, 5 },  { 20, 15 } };
485 	const int expect_cpu0[2][2]	= { { 20, 0 },  { 20, 0 } };
486 	const int expect_cpu1[2][2]	= { { 0, 20 },  { 0, 20 } };
487 	const int expect_bpf[2][2]	= { { 15, 5 },  { 15, 20 } };
488 	const int expect_uniqueid[2][2] = { { 20, 20},  { 20, 20 } };
489 	int port_off = 2, tries = 20, ret;
490 
491 	test_control_single();
492 	test_control_group();
493 	test_control_group_max_num_members();
494 	test_unique_fanout_group_ids();
495 
496 	/* PACKET_FANOUT_MAX */
497 	cfg_max_num_members = 1 << 16;
498 	/* find a set of ports that do not collide onto the same socket */
499 	ret = test_datapath(PACKET_FANOUT_HASH, port_off,
500 			    expect_hash[0], expect_hash[1]);
501 	while (ret) {
502 		fprintf(stderr, "info: trying alternate ports (%d)\n", tries);
503 		ret = test_datapath(PACKET_FANOUT_HASH, ++port_off,
504 				    expect_hash[0], expect_hash[1]);
505 		if (!--tries) {
506 			fprintf(stderr, "too many collisions\n");
507 			return 1;
508 		}
509 	}
510 
511 	ret |= test_datapath(PACKET_FANOUT_HASH | PACKET_FANOUT_FLAG_ROLLOVER,
512 			     port_off, expect_hash_rb[0], expect_hash_rb[1]);
513 	ret |= test_datapath(PACKET_FANOUT_LB,
514 			     port_off, expect_lb[0], expect_lb[1]);
515 	ret |= test_datapath(PACKET_FANOUT_ROLLOVER,
516 			     port_off, expect_rb[0], expect_rb[1]);
517 
518 	ret |= test_datapath(PACKET_FANOUT_CBPF,
519 			     port_off, expect_bpf[0], expect_bpf[1]);
520 	ret |= test_datapath(PACKET_FANOUT_EBPF,
521 			     port_off, expect_bpf[0], expect_bpf[1]);
522 
523 	set_cpuaffinity(0);
524 	ret |= test_datapath(PACKET_FANOUT_CPU, port_off,
525 			     expect_cpu0[0], expect_cpu0[1]);
526 	if (!set_cpuaffinity(1))
527 		/* TODO: test that choice alternates with previous */
528 		ret |= test_datapath(PACKET_FANOUT_CPU, port_off,
529 				     expect_cpu1[0], expect_cpu1[1]);
530 
531 	ret |= test_datapath(PACKET_FANOUT_FLAG_UNIQUEID, port_off,
532 			     expect_uniqueid[0], expect_uniqueid[1]);
533 
534 	if (ret)
535 		return 1;
536 
537 	printf("OK. All tests passed\n");
538 	return 0;
539 }
540