xref: /linux/tools/bpf/bpftool/map.c (revision 83a37b3292f4aca799b355179ad6fbdd78a08e10)
1 /*
2  * Copyright (C) 2017 Netronome Systems, Inc.
3  *
4  * This software is dual licensed under the GNU General License Version 2,
5  * June 1991 as shown in the file COPYING in the top-level directory of this
6  * source tree or the BSD 2-Clause License provided below.  You have the
7  * option to license this software under the complete terms of either license.
8  *
9  * The BSD 2-Clause License:
10  *
11  *     Redistribution and use in source and binary forms, with or
12  *     without modification, are permitted provided that the following
13  *     conditions are met:
14  *
15  *      1. Redistributions of source code must retain the above
16  *         copyright notice, this list of conditions and the following
17  *         disclaimer.
18  *
19  *      2. Redistributions in binary form must reproduce the above
20  *         copyright notice, this list of conditions and the following
21  *         disclaimer in the documentation and/or other materials
22  *         provided with the distribution.
23  *
24  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
25  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
26  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
27  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
28  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
29  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
30  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
31  * SOFTWARE.
32  */
33 
34 /* Author: Jakub Kicinski <kubakici@wp.pl> */
35 
36 #include <assert.h>
37 #include <ctype.h>
38 #include <errno.h>
39 #include <fcntl.h>
40 #include <stdbool.h>
41 #include <stdio.h>
42 #include <stdlib.h>
43 #include <string.h>
44 #include <unistd.h>
45 #include <sys/types.h>
46 #include <sys/stat.h>
47 
48 #include <bpf.h>
49 
50 #include "main.h"
51 
52 static const char * const map_type_name[] = {
53 	[BPF_MAP_TYPE_UNSPEC]		= "unspec",
54 	[BPF_MAP_TYPE_HASH]		= "hash",
55 	[BPF_MAP_TYPE_ARRAY]		= "array",
56 	[BPF_MAP_TYPE_PROG_ARRAY]	= "prog_array",
57 	[BPF_MAP_TYPE_PERF_EVENT_ARRAY]	= "perf_event_array",
58 	[BPF_MAP_TYPE_PERCPU_HASH]	= "percpu_hash",
59 	[BPF_MAP_TYPE_PERCPU_ARRAY]	= "percpu_array",
60 	[BPF_MAP_TYPE_STACK_TRACE]	= "stack_trace",
61 	[BPF_MAP_TYPE_CGROUP_ARRAY]	= "cgroup_array",
62 	[BPF_MAP_TYPE_LRU_HASH]		= "lru_hash",
63 	[BPF_MAP_TYPE_LRU_PERCPU_HASH]	= "lru_percpu_hash",
64 	[BPF_MAP_TYPE_LPM_TRIE]		= "lpm_trie",
65 	[BPF_MAP_TYPE_ARRAY_OF_MAPS]	= "array_of_maps",
66 	[BPF_MAP_TYPE_HASH_OF_MAPS]	= "hash_of_maps",
67 	[BPF_MAP_TYPE_DEVMAP]		= "devmap",
68 	[BPF_MAP_TYPE_SOCKMAP]		= "sockmap",
69 };
70 
71 static unsigned int get_possible_cpus(void)
72 {
73 	static unsigned int result;
74 	char buf[128];
75 	long int n;
76 	char *ptr;
77 	int fd;
78 
79 	if (result)
80 		return result;
81 
82 	fd = open("/sys/devices/system/cpu/possible", O_RDONLY);
83 	if (fd < 0) {
84 		err("can't open sysfs possible cpus\n");
85 		exit(-1);
86 	}
87 
88 	n = read(fd, buf, sizeof(buf));
89 	if (n < 2) {
90 		err("can't read sysfs possible cpus\n");
91 		exit(-1);
92 	}
93 	close(fd);
94 
95 	if (n == sizeof(buf)) {
96 		err("read sysfs possible cpus overflow\n");
97 		exit(-1);
98 	}
99 
100 	ptr = buf;
101 	n = 0;
102 	while (*ptr && *ptr != '\n') {
103 		unsigned int a, b;
104 
105 		if (sscanf(ptr, "%u-%u", &a, &b) == 2) {
106 			n += b - a + 1;
107 
108 			ptr = strchr(ptr, '-') + 1;
109 		} else if (sscanf(ptr, "%u", &a) == 1) {
110 			n++;
111 		} else {
112 			assert(0);
113 		}
114 
115 		while (isdigit(*ptr))
116 			ptr++;
117 		if (*ptr == ',')
118 			ptr++;
119 	}
120 
121 	result = n;
122 
123 	return result;
124 }
125 
126 static bool map_is_per_cpu(__u32 type)
127 {
128 	return type == BPF_MAP_TYPE_PERCPU_HASH ||
129 	       type == BPF_MAP_TYPE_PERCPU_ARRAY ||
130 	       type == BPF_MAP_TYPE_LRU_PERCPU_HASH;
131 }
132 
133 static bool map_is_map_of_maps(__u32 type)
134 {
135 	return type == BPF_MAP_TYPE_ARRAY_OF_MAPS ||
136 	       type == BPF_MAP_TYPE_HASH_OF_MAPS;
137 }
138 
139 static bool map_is_map_of_progs(__u32 type)
140 {
141 	return type == BPF_MAP_TYPE_PROG_ARRAY;
142 }
143 
144 static void *alloc_value(struct bpf_map_info *info)
145 {
146 	if (map_is_per_cpu(info->type))
147 		return malloc(info->value_size * get_possible_cpus());
148 	else
149 		return malloc(info->value_size);
150 }
151 
152 static int map_parse_fd(int *argc, char ***argv)
153 {
154 	int fd;
155 
156 	if (is_prefix(**argv, "id")) {
157 		unsigned int id;
158 		char *endptr;
159 
160 		NEXT_ARGP();
161 
162 		id = strtoul(**argv, &endptr, 0);
163 		if (*endptr) {
164 			err("can't parse %s as ID\n", **argv);
165 			return -1;
166 		}
167 		NEXT_ARGP();
168 
169 		fd = bpf_map_get_fd_by_id(id);
170 		if (fd < 0)
171 			err("get map by id (%u): %s\n", id, strerror(errno));
172 		return fd;
173 	} else if (is_prefix(**argv, "pinned")) {
174 		char *path;
175 
176 		NEXT_ARGP();
177 
178 		path = **argv;
179 		NEXT_ARGP();
180 
181 		return open_obj_pinned_any(path, BPF_OBJ_MAP);
182 	}
183 
184 	err("expected 'id' or 'pinned', got: '%s'?\n", **argv);
185 	return -1;
186 }
187 
188 static int
189 map_parse_fd_and_info(int *argc, char ***argv, void *info, __u32 *info_len)
190 {
191 	int err;
192 	int fd;
193 
194 	fd = map_parse_fd(argc, argv);
195 	if (fd < 0)
196 		return -1;
197 
198 	err = bpf_obj_get_info_by_fd(fd, info, info_len);
199 	if (err) {
200 		err("can't get map info: %s\n", strerror(errno));
201 		close(fd);
202 		return err;
203 	}
204 
205 	return fd;
206 }
207 
208 static void print_entry(struct bpf_map_info *info, unsigned char *key,
209 			unsigned char *value)
210 {
211 	if (!map_is_per_cpu(info->type)) {
212 		bool single_line, break_names;
213 
214 		break_names = info->key_size > 16 || info->value_size > 16;
215 		single_line = info->key_size + info->value_size <= 24 &&
216 			!break_names;
217 
218 		printf("key:%c", break_names ? '\n' : ' ');
219 		print_hex(key, info->key_size, " ");
220 
221 		printf(single_line ? "  " : "\n");
222 
223 		printf("value:%c", break_names ? '\n' : ' ');
224 		print_hex(value, info->value_size, " ");
225 
226 		printf("\n");
227 	} else {
228 		unsigned int i, n;
229 
230 		n = get_possible_cpus();
231 
232 		printf("key:\n");
233 		print_hex(key, info->key_size, " ");
234 		printf("\n");
235 		for (i = 0; i < n; i++) {
236 			printf("value (CPU %02d):%c",
237 			       i, info->value_size > 16 ? '\n' : ' ');
238 			print_hex(value + i * info->value_size,
239 				  info->value_size, " ");
240 			printf("\n");
241 		}
242 	}
243 }
244 
245 static char **parse_bytes(char **argv, const char *name, unsigned char *val,
246 			  unsigned int n)
247 {
248 	unsigned int i = 0;
249 	char *endptr;
250 
251 	while (i < n && argv[i]) {
252 		val[i] = strtoul(argv[i], &endptr, 0);
253 		if (*endptr) {
254 			err("error parsing byte: %s\n", argv[i]);
255 			break;
256 		}
257 		i++;
258 	}
259 
260 	if (i != n) {
261 		err("%s expected %d bytes got %d\n", name, n, i);
262 		return NULL;
263 	}
264 
265 	return argv + i;
266 }
267 
268 static int parse_elem(char **argv, struct bpf_map_info *info,
269 		      void *key, void *value, __u32 key_size, __u32 value_size,
270 		      __u32 *flags, __u32 **value_fd)
271 {
272 	if (!*argv) {
273 		if (!key && !value)
274 			return 0;
275 		err("did not find %s\n", key ? "key" : "value");
276 		return -1;
277 	}
278 
279 	if (is_prefix(*argv, "key")) {
280 		if (!key) {
281 			if (key_size)
282 				err("duplicate key\n");
283 			else
284 				err("unnecessary key\n");
285 			return -1;
286 		}
287 
288 		argv = parse_bytes(argv + 1, "key", key, key_size);
289 		if (!argv)
290 			return -1;
291 
292 		return parse_elem(argv, info, NULL, value, key_size, value_size,
293 				  flags, value_fd);
294 	} else if (is_prefix(*argv, "value")) {
295 		int fd;
296 
297 		if (!value) {
298 			if (value_size)
299 				err("duplicate value\n");
300 			else
301 				err("unnecessary value\n");
302 			return -1;
303 		}
304 
305 		argv++;
306 
307 		if (map_is_map_of_maps(info->type)) {
308 			int argc = 2;
309 
310 			if (value_size != 4) {
311 				err("value smaller than 4B for map in map?\n");
312 				return -1;
313 			}
314 			if (!argv[0] || !argv[1]) {
315 				err("not enough value arguments for map in map\n");
316 				return -1;
317 			}
318 
319 			fd = map_parse_fd(&argc, &argv);
320 			if (fd < 0)
321 				return -1;
322 
323 			*value_fd = value;
324 			**value_fd = fd;
325 		} else if (map_is_map_of_progs(info->type)) {
326 			int argc = 2;
327 
328 			if (value_size != 4) {
329 				err("value smaller than 4B for map of progs?\n");
330 				return -1;
331 			}
332 			if (!argv[0] || !argv[1]) {
333 				err("not enough value arguments for map of progs\n");
334 				return -1;
335 			}
336 
337 			fd = prog_parse_fd(&argc, &argv);
338 			if (fd < 0)
339 				return -1;
340 
341 			*value_fd = value;
342 			**value_fd = fd;
343 		} else {
344 			argv = parse_bytes(argv, "value", value, value_size);
345 			if (!argv)
346 				return -1;
347 		}
348 
349 		return parse_elem(argv, info, key, NULL, key_size, value_size,
350 				  flags, NULL);
351 	} else if (is_prefix(*argv, "any") || is_prefix(*argv, "noexist") ||
352 		   is_prefix(*argv, "exist")) {
353 		if (!flags) {
354 			err("flags specified multiple times: %s\n", *argv);
355 			return -1;
356 		}
357 
358 		if (is_prefix(*argv, "any"))
359 			*flags = BPF_ANY;
360 		else if (is_prefix(*argv, "noexist"))
361 			*flags = BPF_NOEXIST;
362 		else if (is_prefix(*argv, "exist"))
363 			*flags = BPF_EXIST;
364 
365 		return parse_elem(argv + 1, info, key, value, key_size,
366 				  value_size, NULL, value_fd);
367 	}
368 
369 	err("expected key or value, got: %s\n", *argv);
370 	return -1;
371 }
372 
373 static int show_map_close(int fd, struct bpf_map_info *info)
374 {
375 	char *memlock;
376 
377 	memlock = get_fdinfo(fd, "memlock");
378 	close(fd);
379 
380 	printf("%u: ", info->id);
381 	if (info->type < ARRAY_SIZE(map_type_name))
382 		printf("%s  ", map_type_name[info->type]);
383 	else
384 		printf("type %u  ", info->type);
385 
386 	if (*info->name)
387 		printf("name %s  ", info->name);
388 
389 	printf("flags 0x%x\n", info->map_flags);
390 	printf("\tkey %uB  value %uB  max_entries %u",
391 	       info->key_size, info->value_size, info->max_entries);
392 
393 	if (memlock)
394 		printf("  memlock %sB", memlock);
395 	free(memlock);
396 
397 	printf("\n");
398 
399 	return 0;
400 }
401 
402 static int do_show(int argc, char **argv)
403 {
404 	struct bpf_map_info info = {};
405 	__u32 len = sizeof(info);
406 	__u32 id = 0;
407 	int err;
408 	int fd;
409 
410 	if (argc == 2) {
411 		fd = map_parse_fd_and_info(&argc, &argv, &info, &len);
412 		if (fd < 0)
413 			return -1;
414 
415 		return show_map_close(fd, &info);
416 	}
417 
418 	if (argc)
419 		return BAD_ARG();
420 
421 	while (true) {
422 		err = bpf_map_get_next_id(id, &id);
423 		if (err) {
424 			if (errno == ENOENT)
425 				break;
426 			err("can't get next map: %s\n", strerror(errno));
427 			if (errno == EINVAL)
428 				err("kernel too old?\n");
429 			return -1;
430 		}
431 
432 		fd = bpf_map_get_fd_by_id(id);
433 		if (fd < 0) {
434 			err("can't get map by id (%u): %s\n",
435 			    id, strerror(errno));
436 			return -1;
437 		}
438 
439 		err = bpf_obj_get_info_by_fd(fd, &info, &len);
440 		if (err) {
441 			err("can't get map info: %s\n", strerror(errno));
442 			close(fd);
443 			return -1;
444 		}
445 
446 		show_map_close(fd, &info);
447 	}
448 
449 	return errno == ENOENT ? 0 : -1;
450 }
451 
452 static int do_dump(int argc, char **argv)
453 {
454 	void *key, *value, *prev_key;
455 	unsigned int num_elems = 0;
456 	struct bpf_map_info info = {};
457 	__u32 len = sizeof(info);
458 	int err;
459 	int fd;
460 
461 	if (argc != 2)
462 		usage();
463 
464 	fd = map_parse_fd_and_info(&argc, &argv, &info, &len);
465 	if (fd < 0)
466 		return -1;
467 
468 	if (map_is_map_of_maps(info.type) || map_is_map_of_progs(info.type)) {
469 		err("Dumping maps of maps and program maps not supported\n");
470 		close(fd);
471 		return -1;
472 	}
473 
474 	key = malloc(info.key_size);
475 	value = alloc_value(&info);
476 	if (!key || !value) {
477 		err("mem alloc failed\n");
478 		err = -1;
479 		goto exit_free;
480 	}
481 
482 	prev_key = NULL;
483 	while (true) {
484 		err = bpf_map_get_next_key(fd, prev_key, key);
485 		if (err) {
486 			if (errno == ENOENT)
487 				err = 0;
488 			break;
489 		}
490 
491 		if (!bpf_map_lookup_elem(fd, key, value)) {
492 			print_entry(&info, key, value);
493 		} else {
494 			info("can't lookup element with key: ");
495 			print_hex(key, info.key_size, " ");
496 			printf("\n");
497 		}
498 
499 		prev_key = key;
500 		num_elems++;
501 	}
502 
503 	printf("Found %u element%s\n", num_elems, num_elems != 1 ? "s" : "");
504 
505 exit_free:
506 	free(key);
507 	free(value);
508 	close(fd);
509 
510 	return err;
511 }
512 
513 static int do_update(int argc, char **argv)
514 {
515 	struct bpf_map_info info = {};
516 	__u32 len = sizeof(info);
517 	__u32 *value_fd = NULL;
518 	__u32 flags = BPF_ANY;
519 	void *key, *value;
520 	int fd, err;
521 
522 	if (argc < 2)
523 		usage();
524 
525 	fd = map_parse_fd_and_info(&argc, &argv, &info, &len);
526 	if (fd < 0)
527 		return -1;
528 
529 	key = malloc(info.key_size);
530 	value = alloc_value(&info);
531 	if (!key || !value) {
532 		err("mem alloc failed");
533 		err = -1;
534 		goto exit_free;
535 	}
536 
537 	err = parse_elem(argv, &info, key, value, info.key_size,
538 			 info.value_size, &flags, &value_fd);
539 	if (err)
540 		goto exit_free;
541 
542 	err = bpf_map_update_elem(fd, key, value, flags);
543 	if (err) {
544 		err("update failed: %s\n", strerror(errno));
545 		goto exit_free;
546 	}
547 
548 exit_free:
549 	if (value_fd)
550 		close(*value_fd);
551 	free(key);
552 	free(value);
553 	close(fd);
554 
555 	return err;
556 }
557 
558 static int do_lookup(int argc, char **argv)
559 {
560 	struct bpf_map_info info = {};
561 	__u32 len = sizeof(info);
562 	void *key, *value;
563 	int err;
564 	int fd;
565 
566 	if (argc < 2)
567 		usage();
568 
569 	fd = map_parse_fd_and_info(&argc, &argv, &info, &len);
570 	if (fd < 0)
571 		return -1;
572 
573 	key = malloc(info.key_size);
574 	value = alloc_value(&info);
575 	if (!key || !value) {
576 		err("mem alloc failed");
577 		err = -1;
578 		goto exit_free;
579 	}
580 
581 	err = parse_elem(argv, &info, key, NULL, info.key_size, 0, NULL, NULL);
582 	if (err)
583 		goto exit_free;
584 
585 	err = bpf_map_lookup_elem(fd, key, value);
586 	if (!err) {
587 		print_entry(&info, key, value);
588 	} else if (errno == ENOENT) {
589 		printf("key:\n");
590 		print_hex(key, info.key_size, " ");
591 		printf("\n\nNot found\n");
592 	} else {
593 		err("lookup failed: %s\n", strerror(errno));
594 	}
595 
596 exit_free:
597 	free(key);
598 	free(value);
599 	close(fd);
600 
601 	return err;
602 }
603 
604 static int do_getnext(int argc, char **argv)
605 {
606 	struct bpf_map_info info = {};
607 	__u32 len = sizeof(info);
608 	void *key, *nextkey;
609 	int err;
610 	int fd;
611 
612 	if (argc < 2)
613 		usage();
614 
615 	fd = map_parse_fd_and_info(&argc, &argv, &info, &len);
616 	if (fd < 0)
617 		return -1;
618 
619 	key = malloc(info.key_size);
620 	nextkey = malloc(info.key_size);
621 	if (!key || !nextkey) {
622 		err("mem alloc failed");
623 		err = -1;
624 		goto exit_free;
625 	}
626 
627 	if (argc) {
628 		err = parse_elem(argv, &info, key, NULL, info.key_size, 0,
629 				 NULL, NULL);
630 		if (err)
631 			goto exit_free;
632 	} else {
633 		free(key);
634 		key = NULL;
635 	}
636 
637 	err = bpf_map_get_next_key(fd, key, nextkey);
638 	if (err) {
639 		err("can't get next key: %s\n", strerror(errno));
640 		goto exit_free;
641 	}
642 
643 	if (key) {
644 		printf("key:\n");
645 		print_hex(key, info.key_size, " ");
646 		printf("\n");
647 	} else {
648 		printf("key: None\n");
649 	}
650 
651 	printf("next key:\n");
652 	print_hex(nextkey, info.key_size, " ");
653 	printf("\n");
654 
655 exit_free:
656 	free(nextkey);
657 	free(key);
658 	close(fd);
659 
660 	return err;
661 }
662 
663 static int do_delete(int argc, char **argv)
664 {
665 	struct bpf_map_info info = {};
666 	__u32 len = sizeof(info);
667 	void *key;
668 	int err;
669 	int fd;
670 
671 	if (argc < 2)
672 		usage();
673 
674 	fd = map_parse_fd_and_info(&argc, &argv, &info, &len);
675 	if (fd < 0)
676 		return -1;
677 
678 	key = malloc(info.key_size);
679 	if (!key) {
680 		err("mem alloc failed");
681 		err = -1;
682 		goto exit_free;
683 	}
684 
685 	err = parse_elem(argv, &info, key, NULL, info.key_size, 0, NULL, NULL);
686 	if (err)
687 		goto exit_free;
688 
689 	err = bpf_map_delete_elem(fd, key);
690 	if (err)
691 		err("delete failed: %s\n", strerror(errno));
692 
693 exit_free:
694 	free(key);
695 	close(fd);
696 
697 	return err;
698 }
699 
700 static int do_pin(int argc, char **argv)
701 {
702 	return do_pin_any(argc, argv, bpf_map_get_fd_by_id);
703 }
704 
705 static int do_help(int argc, char **argv)
706 {
707 	fprintf(stderr,
708 		"Usage: %s %s show   [MAP]\n"
709 		"       %s %s dump    MAP\n"
710 		"       %s %s update  MAP  key BYTES value VALUE [UPDATE_FLAGS]\n"
711 		"       %s %s lookup  MAP  key BYTES\n"
712 		"       %s %s getnext MAP [key BYTES]\n"
713 		"       %s %s delete  MAP  key BYTES\n"
714 		"       %s %s pin     MAP  FILE\n"
715 		"       %s %s help\n"
716 		"\n"
717 		"       MAP := { id MAP_ID | pinned FILE }\n"
718 		"       " HELP_SPEC_PROGRAM "\n"
719 		"       VALUE := { BYTES | MAP | PROG }\n"
720 		"       UPDATE_FLAGS := { any | exist | noexist }\n"
721 		"",
722 		bin_name, argv[-2], bin_name, argv[-2], bin_name, argv[-2],
723 		bin_name, argv[-2], bin_name, argv[-2], bin_name, argv[-2],
724 		bin_name, argv[-2], bin_name, argv[-2]);
725 
726 	return 0;
727 }
728 
729 static const struct cmd cmds[] = {
730 	{ "show",	do_show },
731 	{ "help",	do_help },
732 	{ "dump",	do_dump },
733 	{ "update",	do_update },
734 	{ "lookup",	do_lookup },
735 	{ "getnext",	do_getnext },
736 	{ "delete",	do_delete },
737 	{ "pin",	do_pin },
738 	{ 0 }
739 };
740 
741 int do_map(int argc, char **argv)
742 {
743 	return cmd_select(cmds, argc, argv, do_help);
744 }
745