xref: /linux/tools/bpf/bpftool/map.c (revision c12a03766788befbb65fc2a87891c9ece8abad07)
1 // SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
2 /* Copyright (C) 2017-2018 Netronome Systems, Inc. */
3 
4 #include <assert.h>
5 #include <errno.h>
6 #include <fcntl.h>
7 #include <linux/err.h>
8 #include <linux/kernel.h>
9 #include <net/if.h>
10 #include <stdbool.h>
11 #include <stdio.h>
12 #include <stdlib.h>
13 #include <string.h>
14 #include <unistd.h>
15 #include <sys/types.h>
16 #include <sys/stat.h>
17 
18 #include <bpf/bpf.h>
19 #include <bpf/btf.h>
20 #include <bpf/hashmap.h>
21 
22 #include "json_writer.h"
23 #include "main.h"
24 
25 static struct hashmap *map_table;
26 
27 static bool map_is_per_cpu(__u32 type)
28 {
29 	return type == BPF_MAP_TYPE_PERCPU_HASH ||
30 	       type == BPF_MAP_TYPE_PERCPU_ARRAY ||
31 	       type == BPF_MAP_TYPE_LRU_PERCPU_HASH ||
32 	       type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE;
33 }
34 
35 static bool map_is_map_of_maps(__u32 type)
36 {
37 	return type == BPF_MAP_TYPE_ARRAY_OF_MAPS ||
38 	       type == BPF_MAP_TYPE_HASH_OF_MAPS;
39 }
40 
41 static bool map_is_map_of_progs(__u32 type)
42 {
43 	return type == BPF_MAP_TYPE_PROG_ARRAY;
44 }
45 
46 static int map_type_from_str(const char *type)
47 {
48 	const char *map_type_str;
49 	unsigned int i;
50 
51 	for (i = 0; ; i++) {
52 		map_type_str = libbpf_bpf_map_type_str(i);
53 		if (!map_type_str)
54 			break;
55 
56 		/* Don't allow prefixing in case of possible future shadowing */
57 		if (!strcmp(map_type_str, type))
58 			return i;
59 	}
60 	return -1;
61 }
62 
63 static void *alloc_value(struct bpf_map_info *info)
64 {
65 	if (map_is_per_cpu(info->type))
66 		return malloc(round_up(info->value_size, 8) *
67 			      get_possible_cpus());
68 	else
69 		return malloc(info->value_size);
70 }
71 
72 static int do_dump_btf(const struct btf_dumper *d,
73 		       struct bpf_map_info *map_info, void *key,
74 		       void *value)
75 {
76 	__u32 value_id;
77 	int ret = 0;
78 
79 	/* start of key-value pair */
80 	jsonw_start_object(d->jw);
81 
82 	if (map_info->btf_key_type_id) {
83 		jsonw_name(d->jw, "key");
84 
85 		ret = btf_dumper_type(d, map_info->btf_key_type_id, key);
86 		if (ret)
87 			goto err_end_obj;
88 	}
89 
90 	value_id = map_info->btf_vmlinux_value_type_id ?
91 		: map_info->btf_value_type_id;
92 
93 	if (!map_is_per_cpu(map_info->type)) {
94 		jsonw_name(d->jw, "value");
95 		ret = btf_dumper_type(d, value_id, value);
96 	} else {
97 		unsigned int i, n, step;
98 
99 		jsonw_name(d->jw, "values");
100 		jsonw_start_array(d->jw);
101 		n = get_possible_cpus();
102 		step = round_up(map_info->value_size, 8);
103 		for (i = 0; i < n; i++) {
104 			jsonw_start_object(d->jw);
105 			jsonw_int_field(d->jw, "cpu", i);
106 			jsonw_name(d->jw, "value");
107 			ret = btf_dumper_type(d, value_id, value + i * step);
108 			jsonw_end_object(d->jw);
109 			if (ret)
110 				break;
111 		}
112 		jsonw_end_array(d->jw);
113 	}
114 
115 err_end_obj:
116 	/* end of key-value pair */
117 	jsonw_end_object(d->jw);
118 
119 	return ret;
120 }
121 
122 static json_writer_t *get_btf_writer(void)
123 {
124 	json_writer_t *jw = jsonw_new(stdout);
125 
126 	if (!jw)
127 		return NULL;
128 	jsonw_pretty(jw, true);
129 
130 	return jw;
131 }
132 
133 static void print_entry_json(struct bpf_map_info *info, unsigned char *key,
134 			     unsigned char *value, struct btf *btf)
135 {
136 	jsonw_start_object(json_wtr);
137 
138 	if (!map_is_per_cpu(info->type)) {
139 		jsonw_name(json_wtr, "key");
140 		print_hex_data_json(key, info->key_size);
141 		jsonw_name(json_wtr, "value");
142 		print_hex_data_json(value, info->value_size);
143 		if (btf) {
144 			struct btf_dumper d = {
145 				.btf = btf,
146 				.jw = json_wtr,
147 				.is_plain_text = false,
148 			};
149 
150 			jsonw_name(json_wtr, "formatted");
151 			do_dump_btf(&d, info, key, value);
152 		}
153 	} else {
154 		unsigned int i, n, step;
155 
156 		n = get_possible_cpus();
157 		step = round_up(info->value_size, 8);
158 
159 		jsonw_name(json_wtr, "key");
160 		print_hex_data_json(key, info->key_size);
161 
162 		jsonw_name(json_wtr, "values");
163 		jsonw_start_array(json_wtr);
164 		for (i = 0; i < n; i++) {
165 			jsonw_start_object(json_wtr);
166 
167 			jsonw_int_field(json_wtr, "cpu", i);
168 
169 			jsonw_name(json_wtr, "value");
170 			print_hex_data_json(value + i * step,
171 					    info->value_size);
172 
173 			jsonw_end_object(json_wtr);
174 		}
175 		jsonw_end_array(json_wtr);
176 		if (btf) {
177 			struct btf_dumper d = {
178 				.btf = btf,
179 				.jw = json_wtr,
180 				.is_plain_text = false,
181 			};
182 
183 			jsonw_name(json_wtr, "formatted");
184 			do_dump_btf(&d, info, key, value);
185 		}
186 	}
187 
188 	jsonw_end_object(json_wtr);
189 }
190 
191 static void
192 print_entry_error_msg(struct bpf_map_info *info, unsigned char *key,
193 		      const char *error_msg)
194 {
195 	int msg_size = strlen(error_msg);
196 	bool single_line, break_names;
197 
198 	break_names = info->key_size > 16 || msg_size > 16;
199 	single_line = info->key_size + msg_size <= 24 && !break_names;
200 
201 	printf("key:%c", break_names ? '\n' : ' ');
202 	fprint_hex(stdout, key, info->key_size, " ");
203 
204 	printf(single_line ? "  " : "\n");
205 
206 	printf("value:%c%s", break_names ? '\n' : ' ', error_msg);
207 
208 	printf("\n");
209 }
210 
211 static void
212 print_entry_error(struct bpf_map_info *map_info, void *key, int lookup_errno)
213 {
214 	/* For prog_array maps or arrays of maps, failure to lookup the value
215 	 * means there is no entry for that key. Do not print an error message
216 	 * in that case.
217 	 */
218 	if ((map_is_map_of_maps(map_info->type) ||
219 	     map_is_map_of_progs(map_info->type)) && lookup_errno == ENOENT)
220 		return;
221 
222 	if (json_output) {
223 		jsonw_start_object(json_wtr);	/* entry */
224 		jsonw_name(json_wtr, "key");
225 		print_hex_data_json(key, map_info->key_size);
226 		jsonw_name(json_wtr, "value");
227 		jsonw_start_object(json_wtr);	/* error */
228 		jsonw_string_field(json_wtr, "error", strerror(lookup_errno));
229 		jsonw_end_object(json_wtr);	/* error */
230 		jsonw_end_object(json_wtr);	/* entry */
231 	} else {
232 		const char *msg = NULL;
233 
234 		if (lookup_errno == ENOENT)
235 			msg = "<no entry>";
236 		else if (lookup_errno == ENOSPC &&
237 			 map_info->type == BPF_MAP_TYPE_REUSEPORT_SOCKARRAY)
238 			msg = "<cannot read>";
239 
240 		print_entry_error_msg(map_info, key,
241 				      msg ? : strerror(lookup_errno));
242 	}
243 }
244 
245 static void print_entry_plain(struct bpf_map_info *info, unsigned char *key,
246 			      unsigned char *value)
247 {
248 	if (!map_is_per_cpu(info->type)) {
249 		bool single_line, break_names;
250 
251 		break_names = info->key_size > 16 || info->value_size > 16;
252 		single_line = info->key_size + info->value_size <= 24 &&
253 			!break_names;
254 
255 		if (info->key_size) {
256 			printf("key:%c", break_names ? '\n' : ' ');
257 			fprint_hex(stdout, key, info->key_size, " ");
258 
259 			printf(single_line ? "  " : "\n");
260 		}
261 
262 		if (info->value_size) {
263 			printf("value:%c", break_names ? '\n' : ' ');
264 			fprint_hex(stdout, value, info->value_size, " ");
265 		}
266 
267 		printf("\n");
268 	} else {
269 		unsigned int i, n, step;
270 
271 		n = get_possible_cpus();
272 		step = round_up(info->value_size, 8);
273 
274 		if (info->key_size) {
275 			printf("key:\n");
276 			fprint_hex(stdout, key, info->key_size, " ");
277 			printf("\n");
278 		}
279 		if (info->value_size) {
280 			for (i = 0; i < n; i++) {
281 				printf("value (CPU %02d):%c",
282 				       i, info->value_size > 16 ? '\n' : ' ');
283 				fprint_hex(stdout, value + i * step,
284 					   info->value_size, " ");
285 				printf("\n");
286 			}
287 		}
288 	}
289 }
290 
291 static char **parse_bytes(char **argv, const char *name, unsigned char *val,
292 			  unsigned int n)
293 {
294 	unsigned int i = 0, base = 0;
295 	char *endptr;
296 
297 	if (is_prefix(*argv, "hex")) {
298 		base = 16;
299 		argv++;
300 	}
301 
302 	while (i < n && argv[i]) {
303 		val[i] = strtoul(argv[i], &endptr, base);
304 		if (*endptr) {
305 			p_err("error parsing byte: %s", argv[i]);
306 			return NULL;
307 		}
308 		i++;
309 	}
310 
311 	if (i != n) {
312 		p_err("%s expected %d bytes got %d", name, n, i);
313 		return NULL;
314 	}
315 
316 	return argv + i;
317 }
318 
319 /* on per cpu maps we must copy the provided value on all value instances */
320 static void fill_per_cpu_value(struct bpf_map_info *info, void *value)
321 {
322 	unsigned int i, n, step;
323 
324 	if (!map_is_per_cpu(info->type))
325 		return;
326 
327 	n = get_possible_cpus();
328 	step = round_up(info->value_size, 8);
329 	for (i = 1; i < n; i++)
330 		memcpy(value + i * step, value, info->value_size);
331 }
332 
333 static int parse_elem(char **argv, struct bpf_map_info *info,
334 		      void *key, void *value, __u32 key_size, __u32 value_size,
335 		      __u32 *flags, __u32 **value_fd)
336 {
337 	if (!*argv) {
338 		if (!key && !value)
339 			return 0;
340 		p_err("did not find %s", key ? "key" : "value");
341 		return -1;
342 	}
343 
344 	if (is_prefix(*argv, "key")) {
345 		if (!key) {
346 			if (key_size)
347 				p_err("duplicate key");
348 			else
349 				p_err("unnecessary key");
350 			return -1;
351 		}
352 
353 		argv = parse_bytes(argv + 1, "key", key, key_size);
354 		if (!argv)
355 			return -1;
356 
357 		return parse_elem(argv, info, NULL, value, key_size, value_size,
358 				  flags, value_fd);
359 	} else if (is_prefix(*argv, "value")) {
360 		int fd;
361 
362 		if (!value) {
363 			if (value_size)
364 				p_err("duplicate value");
365 			else
366 				p_err("unnecessary value");
367 			return -1;
368 		}
369 
370 		argv++;
371 
372 		if (map_is_map_of_maps(info->type)) {
373 			int argc = 2;
374 
375 			if (value_size != 4) {
376 				p_err("value smaller than 4B for map in map?");
377 				return -1;
378 			}
379 			if (!argv[0] || !argv[1]) {
380 				p_err("not enough value arguments for map in map");
381 				return -1;
382 			}
383 
384 			fd = map_parse_fd(&argc, &argv);
385 			if (fd < 0)
386 				return -1;
387 
388 			*value_fd = value;
389 			**value_fd = fd;
390 		} else if (map_is_map_of_progs(info->type)) {
391 			int argc = 2;
392 
393 			if (value_size != 4) {
394 				p_err("value smaller than 4B for map of progs?");
395 				return -1;
396 			}
397 			if (!argv[0] || !argv[1]) {
398 				p_err("not enough value arguments for map of progs");
399 				return -1;
400 			}
401 			if (is_prefix(*argv, "id"))
402 				p_info("Warning: updating program array via MAP_ID, make sure this map is kept open\n"
403 				       "         by some process or pinned otherwise update will be lost");
404 
405 			fd = prog_parse_fd(&argc, &argv);
406 			if (fd < 0)
407 				return -1;
408 
409 			*value_fd = value;
410 			**value_fd = fd;
411 		} else {
412 			argv = parse_bytes(argv, "value", value, value_size);
413 			if (!argv)
414 				return -1;
415 
416 			fill_per_cpu_value(info, value);
417 		}
418 
419 		return parse_elem(argv, info, key, NULL, key_size, value_size,
420 				  flags, NULL);
421 	} else if (is_prefix(*argv, "any") || is_prefix(*argv, "noexist") ||
422 		   is_prefix(*argv, "exist")) {
423 		if (!flags) {
424 			p_err("flags specified multiple times: %s", *argv);
425 			return -1;
426 		}
427 
428 		if (is_prefix(*argv, "any"))
429 			*flags = BPF_ANY;
430 		else if (is_prefix(*argv, "noexist"))
431 			*flags = BPF_NOEXIST;
432 		else if (is_prefix(*argv, "exist"))
433 			*flags = BPF_EXIST;
434 
435 		return parse_elem(argv + 1, info, key, value, key_size,
436 				  value_size, NULL, value_fd);
437 	}
438 
439 	p_err("expected key or value, got: %s", *argv);
440 	return -1;
441 }
442 
443 static void show_map_header_json(struct bpf_map_info *info, json_writer_t *wtr)
444 {
445 	const char *map_type_str;
446 
447 	jsonw_uint_field(wtr, "id", info->id);
448 	map_type_str = libbpf_bpf_map_type_str(info->type);
449 	if (map_type_str)
450 		jsonw_string_field(wtr, "type", map_type_str);
451 	else
452 		jsonw_uint_field(wtr, "type", info->type);
453 
454 	if (*info->name)
455 		jsonw_string_field(wtr, "name", info->name);
456 
457 	jsonw_name(wtr, "flags");
458 	jsonw_printf(wtr, "%d", info->map_flags);
459 }
460 
461 static int show_map_close_json(int fd, struct bpf_map_info *info)
462 {
463 	char *memlock, *frozen_str;
464 	int frozen = 0;
465 
466 	memlock = get_fdinfo(fd, "memlock");
467 	frozen_str = get_fdinfo(fd, "frozen");
468 
469 	jsonw_start_object(json_wtr);
470 
471 	show_map_header_json(info, json_wtr);
472 
473 	print_dev_json(info->ifindex, info->netns_dev, info->netns_ino);
474 
475 	jsonw_uint_field(json_wtr, "bytes_key", info->key_size);
476 	jsonw_uint_field(json_wtr, "bytes_value", info->value_size);
477 	jsonw_uint_field(json_wtr, "max_entries", info->max_entries);
478 
479 	if (memlock)
480 		jsonw_int_field(json_wtr, "bytes_memlock", atoll(memlock));
481 	free(memlock);
482 
483 	if (info->type == BPF_MAP_TYPE_PROG_ARRAY) {
484 		char *owner_prog_type = get_fdinfo(fd, "owner_prog_type");
485 		char *owner_jited = get_fdinfo(fd, "owner_jited");
486 
487 		if (owner_prog_type) {
488 			unsigned int prog_type = atoi(owner_prog_type);
489 			const char *prog_type_str;
490 
491 			prog_type_str = libbpf_bpf_prog_type_str(prog_type);
492 			if (prog_type_str)
493 				jsonw_string_field(json_wtr, "owner_prog_type",
494 						   prog_type_str);
495 			else
496 				jsonw_uint_field(json_wtr, "owner_prog_type",
497 						 prog_type);
498 		}
499 		if (owner_jited)
500 			jsonw_bool_field(json_wtr, "owner_jited",
501 					 !!atoi(owner_jited));
502 
503 		free(owner_prog_type);
504 		free(owner_jited);
505 	}
506 	close(fd);
507 
508 	if (frozen_str) {
509 		frozen = atoi(frozen_str);
510 		free(frozen_str);
511 	}
512 	jsonw_int_field(json_wtr, "frozen", frozen);
513 
514 	if (info->btf_id)
515 		jsonw_int_field(json_wtr, "btf_id", info->btf_id);
516 
517 	if (!hashmap__empty(map_table)) {
518 		struct hashmap_entry *entry;
519 
520 		jsonw_name(json_wtr, "pinned");
521 		jsonw_start_array(json_wtr);
522 		hashmap__for_each_key_entry(map_table, entry,
523 					    u32_as_hash_field(info->id))
524 			jsonw_string(json_wtr, entry->value);
525 		jsonw_end_array(json_wtr);
526 	}
527 
528 	emit_obj_refs_json(refs_table, info->id, json_wtr);
529 
530 	jsonw_end_object(json_wtr);
531 
532 	return 0;
533 }
534 
535 static void show_map_header_plain(struct bpf_map_info *info)
536 {
537 	const char *map_type_str;
538 
539 	printf("%u: ", info->id);
540 
541 	map_type_str = libbpf_bpf_map_type_str(info->type);
542 	if (map_type_str)
543 		printf("%s  ", map_type_str);
544 	else
545 		printf("type %u  ", info->type);
546 
547 	if (*info->name)
548 		printf("name %s  ", info->name);
549 
550 	printf("flags 0x%x", info->map_flags);
551 	print_dev_plain(info->ifindex, info->netns_dev, info->netns_ino);
552 	printf("\n");
553 }
554 
555 static int show_map_close_plain(int fd, struct bpf_map_info *info)
556 {
557 	char *memlock, *frozen_str;
558 	int frozen = 0;
559 
560 	memlock = get_fdinfo(fd, "memlock");
561 	frozen_str = get_fdinfo(fd, "frozen");
562 
563 	show_map_header_plain(info);
564 	printf("\tkey %uB  value %uB  max_entries %u",
565 	       info->key_size, info->value_size, info->max_entries);
566 
567 	if (memlock)
568 		printf("  memlock %sB", memlock);
569 	free(memlock);
570 
571 	if (info->type == BPF_MAP_TYPE_PROG_ARRAY) {
572 		char *owner_prog_type = get_fdinfo(fd, "owner_prog_type");
573 		char *owner_jited = get_fdinfo(fd, "owner_jited");
574 
575 		if (owner_prog_type || owner_jited)
576 			printf("\n\t");
577 		if (owner_prog_type) {
578 			unsigned int prog_type = atoi(owner_prog_type);
579 			const char *prog_type_str;
580 
581 			prog_type_str = libbpf_bpf_prog_type_str(prog_type);
582 			if (prog_type_str)
583 				printf("owner_prog_type %s  ", prog_type_str);
584 			else
585 				printf("owner_prog_type %d  ", prog_type);
586 		}
587 		if (owner_jited)
588 			printf("owner%s jited",
589 			       atoi(owner_jited) ? "" : " not");
590 
591 		free(owner_prog_type);
592 		free(owner_jited);
593 	}
594 	close(fd);
595 
596 	if (!hashmap__empty(map_table)) {
597 		struct hashmap_entry *entry;
598 
599 		hashmap__for_each_key_entry(map_table, entry,
600 					    u32_as_hash_field(info->id))
601 			printf("\n\tpinned %s", (char *)entry->value);
602 	}
603 
604 	if (frozen_str) {
605 		frozen = atoi(frozen_str);
606 		free(frozen_str);
607 	}
608 
609 	if (info->btf_id || frozen)
610 		printf("\n\t");
611 
612 	if (info->btf_id)
613 		printf("btf_id %d", info->btf_id);
614 
615 	if (frozen)
616 		printf("%sfrozen", info->btf_id ? "  " : "");
617 
618 	emit_obj_refs_plain(refs_table, info->id, "\n\tpids ");
619 
620 	printf("\n");
621 	return 0;
622 }
623 
624 static int do_show_subset(int argc, char **argv)
625 {
626 	struct bpf_map_info info = {};
627 	__u32 len = sizeof(info);
628 	int *fds = NULL;
629 	int nb_fds, i;
630 	int err = -1;
631 
632 	fds = malloc(sizeof(int));
633 	if (!fds) {
634 		p_err("mem alloc failed");
635 		return -1;
636 	}
637 	nb_fds = map_parse_fds(&argc, &argv, &fds);
638 	if (nb_fds < 1)
639 		goto exit_free;
640 
641 	if (json_output && nb_fds > 1)
642 		jsonw_start_array(json_wtr);	/* root array */
643 	for (i = 0; i < nb_fds; i++) {
644 		err = bpf_obj_get_info_by_fd(fds[i], &info, &len);
645 		if (err) {
646 			p_err("can't get map info: %s",
647 			      strerror(errno));
648 			for (; i < nb_fds; i++)
649 				close(fds[i]);
650 			break;
651 		}
652 
653 		if (json_output)
654 			show_map_close_json(fds[i], &info);
655 		else
656 			show_map_close_plain(fds[i], &info);
657 
658 		close(fds[i]);
659 	}
660 	if (json_output && nb_fds > 1)
661 		jsonw_end_array(json_wtr);	/* root array */
662 
663 exit_free:
664 	free(fds);
665 	return err;
666 }
667 
668 static int do_show(int argc, char **argv)
669 {
670 	struct bpf_map_info info = {};
671 	__u32 len = sizeof(info);
672 	__u32 id = 0;
673 	int err;
674 	int fd;
675 
676 	if (show_pinned) {
677 		map_table = hashmap__new(hash_fn_for_key_as_id,
678 					 equal_fn_for_key_as_id, NULL);
679 		if (IS_ERR(map_table)) {
680 			p_err("failed to create hashmap for pinned paths");
681 			return -1;
682 		}
683 		build_pinned_obj_table(map_table, BPF_OBJ_MAP);
684 	}
685 	build_obj_refs_table(&refs_table, BPF_OBJ_MAP);
686 
687 	if (argc == 2)
688 		return do_show_subset(argc, argv);
689 
690 	if (argc)
691 		return BAD_ARG();
692 
693 	if (json_output)
694 		jsonw_start_array(json_wtr);
695 	while (true) {
696 		err = bpf_map_get_next_id(id, &id);
697 		if (err) {
698 			if (errno == ENOENT)
699 				break;
700 			p_err("can't get next map: %s%s", strerror(errno),
701 			      errno == EINVAL ? " -- kernel too old?" : "");
702 			break;
703 		}
704 
705 		fd = bpf_map_get_fd_by_id(id);
706 		if (fd < 0) {
707 			if (errno == ENOENT)
708 				continue;
709 			p_err("can't get map by id (%u): %s",
710 			      id, strerror(errno));
711 			break;
712 		}
713 
714 		err = bpf_obj_get_info_by_fd(fd, &info, &len);
715 		if (err) {
716 			p_err("can't get map info: %s", strerror(errno));
717 			close(fd);
718 			break;
719 		}
720 
721 		if (json_output)
722 			show_map_close_json(fd, &info);
723 		else
724 			show_map_close_plain(fd, &info);
725 	}
726 	if (json_output)
727 		jsonw_end_array(json_wtr);
728 
729 	delete_obj_refs_table(refs_table);
730 
731 	if (show_pinned)
732 		delete_pinned_obj_table(map_table);
733 
734 	return errno == ENOENT ? 0 : -1;
735 }
736 
737 static int dump_map_elem(int fd, void *key, void *value,
738 			 struct bpf_map_info *map_info, struct btf *btf,
739 			 json_writer_t *btf_wtr)
740 {
741 	if (bpf_map_lookup_elem(fd, key, value)) {
742 		print_entry_error(map_info, key, errno);
743 		return -1;
744 	}
745 
746 	if (json_output) {
747 		print_entry_json(map_info, key, value, btf);
748 	} else if (btf) {
749 		struct btf_dumper d = {
750 			.btf = btf,
751 			.jw = btf_wtr,
752 			.is_plain_text = true,
753 		};
754 
755 		do_dump_btf(&d, map_info, key, value);
756 	} else {
757 		print_entry_plain(map_info, key, value);
758 	}
759 
760 	return 0;
761 }
762 
763 static int maps_have_btf(int *fds, int nb_fds)
764 {
765 	struct bpf_map_info info = {};
766 	__u32 len = sizeof(info);
767 	int err, i;
768 
769 	for (i = 0; i < nb_fds; i++) {
770 		err = bpf_obj_get_info_by_fd(fds[i], &info, &len);
771 		if (err) {
772 			p_err("can't get map info: %s", strerror(errno));
773 			return -1;
774 		}
775 
776 		if (!info.btf_id)
777 			return 0;
778 	}
779 
780 	return 1;
781 }
782 
783 static struct btf *btf_vmlinux;
784 
785 static int get_map_kv_btf(const struct bpf_map_info *info, struct btf **btf)
786 {
787 	int err = 0;
788 
789 	if (info->btf_vmlinux_value_type_id) {
790 		if (!btf_vmlinux) {
791 			btf_vmlinux = libbpf_find_kernel_btf();
792 			err = libbpf_get_error(btf_vmlinux);
793 			if (err) {
794 				p_err("failed to get kernel btf");
795 				return err;
796 			}
797 		}
798 		*btf = btf_vmlinux;
799 	} else if (info->btf_value_type_id) {
800 		*btf = btf__load_from_kernel_by_id(info->btf_id);
801 		err = libbpf_get_error(*btf);
802 		if (err)
803 			p_err("failed to get btf");
804 	} else {
805 		*btf = NULL;
806 	}
807 
808 	return err;
809 }
810 
811 static void free_map_kv_btf(struct btf *btf)
812 {
813 	if (!libbpf_get_error(btf) && btf != btf_vmlinux)
814 		btf__free(btf);
815 }
816 
817 static void free_btf_vmlinux(void)
818 {
819 	if (!libbpf_get_error(btf_vmlinux))
820 		btf__free(btf_vmlinux);
821 }
822 
823 static int
824 map_dump(int fd, struct bpf_map_info *info, json_writer_t *wtr,
825 	 bool show_header)
826 {
827 	void *key, *value, *prev_key;
828 	unsigned int num_elems = 0;
829 	struct btf *btf = NULL;
830 	int err;
831 
832 	key = malloc(info->key_size);
833 	value = alloc_value(info);
834 	if (!key || !value) {
835 		p_err("mem alloc failed");
836 		err = -1;
837 		goto exit_free;
838 	}
839 
840 	prev_key = NULL;
841 
842 	if (wtr) {
843 		err = get_map_kv_btf(info, &btf);
844 		if (err) {
845 			goto exit_free;
846 		}
847 
848 		if (show_header) {
849 			jsonw_start_object(wtr);	/* map object */
850 			show_map_header_json(info, wtr);
851 			jsonw_name(wtr, "elements");
852 		}
853 		jsonw_start_array(wtr);		/* elements */
854 	} else if (show_header) {
855 		show_map_header_plain(info);
856 	}
857 
858 	if (info->type == BPF_MAP_TYPE_REUSEPORT_SOCKARRAY &&
859 	    info->value_size != 8) {
860 		const char *map_type_str;
861 
862 		map_type_str = libbpf_bpf_map_type_str(info->type);
863 		p_info("Warning: cannot read values from %s map with value_size != 8",
864 		       map_type_str);
865 	}
866 	while (true) {
867 		err = bpf_map_get_next_key(fd, prev_key, key);
868 		if (err) {
869 			if (errno == ENOENT)
870 				err = 0;
871 			break;
872 		}
873 		if (!dump_map_elem(fd, key, value, info, btf, wtr))
874 			num_elems++;
875 		prev_key = key;
876 	}
877 
878 	if (wtr) {
879 		jsonw_end_array(wtr);	/* elements */
880 		if (show_header)
881 			jsonw_end_object(wtr);	/* map object */
882 	} else {
883 		printf("Found %u element%s\n", num_elems,
884 		       num_elems != 1 ? "s" : "");
885 	}
886 
887 exit_free:
888 	free(key);
889 	free(value);
890 	close(fd);
891 	free_map_kv_btf(btf);
892 
893 	return err;
894 }
895 
896 static int do_dump(int argc, char **argv)
897 {
898 	json_writer_t *wtr = NULL, *btf_wtr = NULL;
899 	struct bpf_map_info info = {};
900 	int nb_fds, i = 0;
901 	__u32 len = sizeof(info);
902 	int *fds = NULL;
903 	int err = -1;
904 
905 	if (argc != 2)
906 		usage();
907 
908 	fds = malloc(sizeof(int));
909 	if (!fds) {
910 		p_err("mem alloc failed");
911 		return -1;
912 	}
913 	nb_fds = map_parse_fds(&argc, &argv, &fds);
914 	if (nb_fds < 1)
915 		goto exit_free;
916 
917 	if (json_output) {
918 		wtr = json_wtr;
919 	} else {
920 		int do_plain_btf;
921 
922 		do_plain_btf = maps_have_btf(fds, nb_fds);
923 		if (do_plain_btf < 0)
924 			goto exit_close;
925 
926 		if (do_plain_btf) {
927 			btf_wtr = get_btf_writer();
928 			wtr = btf_wtr;
929 			if (!btf_wtr)
930 				p_info("failed to create json writer for btf. falling back to plain output");
931 		}
932 	}
933 
934 	if (wtr && nb_fds > 1)
935 		jsonw_start_array(wtr);	/* root array */
936 	for (i = 0; i < nb_fds; i++) {
937 		if (bpf_obj_get_info_by_fd(fds[i], &info, &len)) {
938 			p_err("can't get map info: %s", strerror(errno));
939 			break;
940 		}
941 		err = map_dump(fds[i], &info, wtr, nb_fds > 1);
942 		if (!wtr && i != nb_fds - 1)
943 			printf("\n");
944 
945 		if (err)
946 			break;
947 		close(fds[i]);
948 	}
949 	if (wtr && nb_fds > 1)
950 		jsonw_end_array(wtr);	/* root array */
951 
952 	if (btf_wtr)
953 		jsonw_destroy(&btf_wtr);
954 exit_close:
955 	for (; i < nb_fds; i++)
956 		close(fds[i]);
957 exit_free:
958 	free(fds);
959 	free_btf_vmlinux();
960 	return err;
961 }
962 
963 static int alloc_key_value(struct bpf_map_info *info, void **key, void **value)
964 {
965 	*key = NULL;
966 	*value = NULL;
967 
968 	if (info->key_size) {
969 		*key = malloc(info->key_size);
970 		if (!*key) {
971 			p_err("key mem alloc failed");
972 			return -1;
973 		}
974 	}
975 
976 	if (info->value_size) {
977 		*value = alloc_value(info);
978 		if (!*value) {
979 			p_err("value mem alloc failed");
980 			free(*key);
981 			*key = NULL;
982 			return -1;
983 		}
984 	}
985 
986 	return 0;
987 }
988 
989 static int do_update(int argc, char **argv)
990 {
991 	struct bpf_map_info info = {};
992 	__u32 len = sizeof(info);
993 	__u32 *value_fd = NULL;
994 	__u32 flags = BPF_ANY;
995 	void *key, *value;
996 	int fd, err;
997 
998 	if (argc < 2)
999 		usage();
1000 
1001 	fd = map_parse_fd_and_info(&argc, &argv, &info, &len);
1002 	if (fd < 0)
1003 		return -1;
1004 
1005 	err = alloc_key_value(&info, &key, &value);
1006 	if (err)
1007 		goto exit_free;
1008 
1009 	err = parse_elem(argv, &info, key, value, info.key_size,
1010 			 info.value_size, &flags, &value_fd);
1011 	if (err)
1012 		goto exit_free;
1013 
1014 	err = bpf_map_update_elem(fd, key, value, flags);
1015 	if (err) {
1016 		p_err("update failed: %s", strerror(errno));
1017 		goto exit_free;
1018 	}
1019 
1020 exit_free:
1021 	if (value_fd)
1022 		close(*value_fd);
1023 	free(key);
1024 	free(value);
1025 	close(fd);
1026 
1027 	if (!err && json_output)
1028 		jsonw_null(json_wtr);
1029 	return err;
1030 }
1031 
1032 static void print_key_value(struct bpf_map_info *info, void *key,
1033 			    void *value)
1034 {
1035 	json_writer_t *btf_wtr;
1036 	struct btf *btf;
1037 
1038 	if (get_map_kv_btf(info, &btf))
1039 		return;
1040 
1041 	if (json_output) {
1042 		print_entry_json(info, key, value, btf);
1043 	} else if (btf) {
1044 		/* if here json_wtr wouldn't have been initialised,
1045 		 * so let's create separate writer for btf
1046 		 */
1047 		btf_wtr = get_btf_writer();
1048 		if (!btf_wtr) {
1049 			p_info("failed to create json writer for btf. falling back to plain output");
1050 			btf__free(btf);
1051 			btf = NULL;
1052 			print_entry_plain(info, key, value);
1053 		} else {
1054 			struct btf_dumper d = {
1055 				.btf = btf,
1056 				.jw = btf_wtr,
1057 				.is_plain_text = true,
1058 			};
1059 
1060 			do_dump_btf(&d, info, key, value);
1061 			jsonw_destroy(&btf_wtr);
1062 		}
1063 	} else {
1064 		print_entry_plain(info, key, value);
1065 	}
1066 	btf__free(btf);
1067 }
1068 
1069 static int do_lookup(int argc, char **argv)
1070 {
1071 	struct bpf_map_info info = {};
1072 	__u32 len = sizeof(info);
1073 	void *key, *value;
1074 	int err;
1075 	int fd;
1076 
1077 	if (argc < 2)
1078 		usage();
1079 
1080 	fd = map_parse_fd_and_info(&argc, &argv, &info, &len);
1081 	if (fd < 0)
1082 		return -1;
1083 
1084 	err = alloc_key_value(&info, &key, &value);
1085 	if (err)
1086 		goto exit_free;
1087 
1088 	err = parse_elem(argv, &info, key, NULL, info.key_size, 0, NULL, NULL);
1089 	if (err)
1090 		goto exit_free;
1091 
1092 	err = bpf_map_lookup_elem(fd, key, value);
1093 	if (err) {
1094 		if (errno == ENOENT) {
1095 			if (json_output) {
1096 				jsonw_null(json_wtr);
1097 			} else {
1098 				printf("key:\n");
1099 				fprint_hex(stdout, key, info.key_size, " ");
1100 				printf("\n\nNot found\n");
1101 			}
1102 		} else {
1103 			p_err("lookup failed: %s", strerror(errno));
1104 		}
1105 
1106 		goto exit_free;
1107 	}
1108 
1109 	/* here means bpf_map_lookup_elem() succeeded */
1110 	print_key_value(&info, key, value);
1111 
1112 exit_free:
1113 	free(key);
1114 	free(value);
1115 	close(fd);
1116 
1117 	return err;
1118 }
1119 
1120 static int do_getnext(int argc, char **argv)
1121 {
1122 	struct bpf_map_info info = {};
1123 	__u32 len = sizeof(info);
1124 	void *key, *nextkey;
1125 	int err;
1126 	int fd;
1127 
1128 	if (argc < 2)
1129 		usage();
1130 
1131 	fd = map_parse_fd_and_info(&argc, &argv, &info, &len);
1132 	if (fd < 0)
1133 		return -1;
1134 
1135 	key = malloc(info.key_size);
1136 	nextkey = malloc(info.key_size);
1137 	if (!key || !nextkey) {
1138 		p_err("mem alloc failed");
1139 		err = -1;
1140 		goto exit_free;
1141 	}
1142 
1143 	if (argc) {
1144 		err = parse_elem(argv, &info, key, NULL, info.key_size, 0,
1145 				 NULL, NULL);
1146 		if (err)
1147 			goto exit_free;
1148 	} else {
1149 		free(key);
1150 		key = NULL;
1151 	}
1152 
1153 	err = bpf_map_get_next_key(fd, key, nextkey);
1154 	if (err) {
1155 		p_err("can't get next key: %s", strerror(errno));
1156 		goto exit_free;
1157 	}
1158 
1159 	if (json_output) {
1160 		jsonw_start_object(json_wtr);
1161 		if (key) {
1162 			jsonw_name(json_wtr, "key");
1163 			print_hex_data_json(key, info.key_size);
1164 		} else {
1165 			jsonw_null_field(json_wtr, "key");
1166 		}
1167 		jsonw_name(json_wtr, "next_key");
1168 		print_hex_data_json(nextkey, info.key_size);
1169 		jsonw_end_object(json_wtr);
1170 	} else {
1171 		if (key) {
1172 			printf("key:\n");
1173 			fprint_hex(stdout, key, info.key_size, " ");
1174 			printf("\n");
1175 		} else {
1176 			printf("key: None\n");
1177 		}
1178 		printf("next key:\n");
1179 		fprint_hex(stdout, nextkey, info.key_size, " ");
1180 		printf("\n");
1181 	}
1182 
1183 exit_free:
1184 	free(nextkey);
1185 	free(key);
1186 	close(fd);
1187 
1188 	return err;
1189 }
1190 
1191 static int do_delete(int argc, char **argv)
1192 {
1193 	struct bpf_map_info info = {};
1194 	__u32 len = sizeof(info);
1195 	void *key;
1196 	int err;
1197 	int fd;
1198 
1199 	if (argc < 2)
1200 		usage();
1201 
1202 	fd = map_parse_fd_and_info(&argc, &argv, &info, &len);
1203 	if (fd < 0)
1204 		return -1;
1205 
1206 	key = malloc(info.key_size);
1207 	if (!key) {
1208 		p_err("mem alloc failed");
1209 		err = -1;
1210 		goto exit_free;
1211 	}
1212 
1213 	err = parse_elem(argv, &info, key, NULL, info.key_size, 0, NULL, NULL);
1214 	if (err)
1215 		goto exit_free;
1216 
1217 	err = bpf_map_delete_elem(fd, key);
1218 	if (err)
1219 		p_err("delete failed: %s", strerror(errno));
1220 
1221 exit_free:
1222 	free(key);
1223 	close(fd);
1224 
1225 	if (!err && json_output)
1226 		jsonw_null(json_wtr);
1227 	return err;
1228 }
1229 
1230 static int do_pin(int argc, char **argv)
1231 {
1232 	int err;
1233 
1234 	err = do_pin_any(argc, argv, map_parse_fd);
1235 	if (!err && json_output)
1236 		jsonw_null(json_wtr);
1237 	return err;
1238 }
1239 
1240 static int do_create(int argc, char **argv)
1241 {
1242 	LIBBPF_OPTS(bpf_map_create_opts, attr);
1243 	enum bpf_map_type map_type = BPF_MAP_TYPE_UNSPEC;
1244 	__u32 key_size = 0, value_size = 0, max_entries = 0;
1245 	const char *map_name = NULL;
1246 	const char *pinfile;
1247 	int err = -1, fd;
1248 
1249 	if (!REQ_ARGS(7))
1250 		return -1;
1251 	pinfile = GET_ARG();
1252 
1253 	while (argc) {
1254 		if (!REQ_ARGS(2))
1255 			return -1;
1256 
1257 		if (is_prefix(*argv, "type")) {
1258 			NEXT_ARG();
1259 
1260 			if (map_type) {
1261 				p_err("map type already specified");
1262 				goto exit;
1263 			}
1264 
1265 			map_type = map_type_from_str(*argv);
1266 			if ((int)map_type < 0) {
1267 				p_err("unrecognized map type: %s", *argv);
1268 				goto exit;
1269 			}
1270 			NEXT_ARG();
1271 		} else if (is_prefix(*argv, "name")) {
1272 			NEXT_ARG();
1273 			map_name = GET_ARG();
1274 		} else if (is_prefix(*argv, "key")) {
1275 			if (parse_u32_arg(&argc, &argv, &key_size,
1276 					  "key size"))
1277 				goto exit;
1278 		} else if (is_prefix(*argv, "value")) {
1279 			if (parse_u32_arg(&argc, &argv, &value_size,
1280 					  "value size"))
1281 				goto exit;
1282 		} else if (is_prefix(*argv, "entries")) {
1283 			if (parse_u32_arg(&argc, &argv, &max_entries,
1284 					  "max entries"))
1285 				goto exit;
1286 		} else if (is_prefix(*argv, "flags")) {
1287 			if (parse_u32_arg(&argc, &argv, &attr.map_flags,
1288 					  "flags"))
1289 				goto exit;
1290 		} else if (is_prefix(*argv, "dev")) {
1291 			NEXT_ARG();
1292 
1293 			if (attr.map_ifindex) {
1294 				p_err("offload device already specified");
1295 				goto exit;
1296 			}
1297 
1298 			attr.map_ifindex = if_nametoindex(*argv);
1299 			if (!attr.map_ifindex) {
1300 				p_err("unrecognized netdevice '%s': %s",
1301 				      *argv, strerror(errno));
1302 				goto exit;
1303 			}
1304 			NEXT_ARG();
1305 		} else if (is_prefix(*argv, "inner_map")) {
1306 			struct bpf_map_info info = {};
1307 			__u32 len = sizeof(info);
1308 			int inner_map_fd;
1309 
1310 			NEXT_ARG();
1311 			if (!REQ_ARGS(2))
1312 				usage();
1313 			inner_map_fd = map_parse_fd_and_info(&argc, &argv,
1314 							     &info, &len);
1315 			if (inner_map_fd < 0)
1316 				return -1;
1317 			attr.inner_map_fd = inner_map_fd;
1318 		} else {
1319 			p_err("unknown arg %s", *argv);
1320 			goto exit;
1321 		}
1322 	}
1323 
1324 	if (!map_name) {
1325 		p_err("map name not specified");
1326 		goto exit;
1327 	}
1328 
1329 	set_max_rlimit();
1330 
1331 	fd = bpf_map_create(map_type, map_name, key_size, value_size, max_entries, &attr);
1332 	if (fd < 0) {
1333 		p_err("map create failed: %s", strerror(errno));
1334 		goto exit;
1335 	}
1336 
1337 	err = do_pin_fd(fd, pinfile);
1338 	close(fd);
1339 	if (err)
1340 		goto exit;
1341 
1342 	if (json_output)
1343 		jsonw_null(json_wtr);
1344 
1345 exit:
1346 	if (attr.inner_map_fd > 0)
1347 		close(attr.inner_map_fd);
1348 
1349 	return err;
1350 }
1351 
1352 static int do_pop_dequeue(int argc, char **argv)
1353 {
1354 	struct bpf_map_info info = {};
1355 	__u32 len = sizeof(info);
1356 	void *key, *value;
1357 	int err;
1358 	int fd;
1359 
1360 	if (argc < 2)
1361 		usage();
1362 
1363 	fd = map_parse_fd_and_info(&argc, &argv, &info, &len);
1364 	if (fd < 0)
1365 		return -1;
1366 
1367 	err = alloc_key_value(&info, &key, &value);
1368 	if (err)
1369 		goto exit_free;
1370 
1371 	err = bpf_map_lookup_and_delete_elem(fd, key, value);
1372 	if (err) {
1373 		if (errno == ENOENT) {
1374 			if (json_output)
1375 				jsonw_null(json_wtr);
1376 			else
1377 				printf("Error: empty map\n");
1378 		} else {
1379 			p_err("pop failed: %s", strerror(errno));
1380 		}
1381 
1382 		goto exit_free;
1383 	}
1384 
1385 	print_key_value(&info, key, value);
1386 
1387 exit_free:
1388 	free(key);
1389 	free(value);
1390 	close(fd);
1391 
1392 	return err;
1393 }
1394 
1395 static int do_freeze(int argc, char **argv)
1396 {
1397 	int err, fd;
1398 
1399 	if (!REQ_ARGS(2))
1400 		return -1;
1401 
1402 	fd = map_parse_fd(&argc, &argv);
1403 	if (fd < 0)
1404 		return -1;
1405 
1406 	if (argc) {
1407 		close(fd);
1408 		return BAD_ARG();
1409 	}
1410 
1411 	err = bpf_map_freeze(fd);
1412 	close(fd);
1413 	if (err) {
1414 		p_err("failed to freeze map: %s", strerror(errno));
1415 		return err;
1416 	}
1417 
1418 	if (json_output)
1419 		jsonw_null(json_wtr);
1420 
1421 	return 0;
1422 }
1423 
1424 static int do_help(int argc, char **argv)
1425 {
1426 	if (json_output) {
1427 		jsonw_null(json_wtr);
1428 		return 0;
1429 	}
1430 
1431 	fprintf(stderr,
1432 		"Usage: %1$s %2$s { show | list }   [MAP]\n"
1433 		"       %1$s %2$s create     FILE type TYPE key KEY_SIZE value VALUE_SIZE \\\n"
1434 		"                                  entries MAX_ENTRIES name NAME [flags FLAGS] \\\n"
1435 		"                                  [inner_map MAP] [dev NAME]\n"
1436 		"       %1$s %2$s dump       MAP\n"
1437 		"       %1$s %2$s update     MAP [key DATA] [value VALUE] [UPDATE_FLAGS]\n"
1438 		"       %1$s %2$s lookup     MAP [key DATA]\n"
1439 		"       %1$s %2$s getnext    MAP [key DATA]\n"
1440 		"       %1$s %2$s delete     MAP  key DATA\n"
1441 		"       %1$s %2$s pin        MAP  FILE\n"
1442 		"       %1$s %2$s event_pipe MAP [cpu N index M]\n"
1443 		"       %1$s %2$s peek       MAP\n"
1444 		"       %1$s %2$s push       MAP value VALUE\n"
1445 		"       %1$s %2$s pop        MAP\n"
1446 		"       %1$s %2$s enqueue    MAP value VALUE\n"
1447 		"       %1$s %2$s dequeue    MAP\n"
1448 		"       %1$s %2$s freeze     MAP\n"
1449 		"       %1$s %2$s help\n"
1450 		"\n"
1451 		"       " HELP_SPEC_MAP "\n"
1452 		"       DATA := { [hex] BYTES }\n"
1453 		"       " HELP_SPEC_PROGRAM "\n"
1454 		"       VALUE := { DATA | MAP | PROG }\n"
1455 		"       UPDATE_FLAGS := { any | exist | noexist }\n"
1456 		"       TYPE := { hash | array | prog_array | perf_event_array | percpu_hash |\n"
1457 		"                 percpu_array | stack_trace | cgroup_array | lru_hash |\n"
1458 		"                 lru_percpu_hash | lpm_trie | array_of_maps | hash_of_maps |\n"
1459 		"                 devmap | devmap_hash | sockmap | cpumap | xskmap | sockhash |\n"
1460 		"                 cgroup_storage | reuseport_sockarray | percpu_cgroup_storage |\n"
1461 		"                 queue | stack | sk_storage | struct_ops | ringbuf | inode_storage |\n"
1462 		"                 task_storage | bloom_filter | user_ringbuf }\n"
1463 		"       " HELP_SPEC_OPTIONS " |\n"
1464 		"                    {-f|--bpffs} | {-n|--nomount} }\n"
1465 		"",
1466 		bin_name, argv[-2]);
1467 
1468 	return 0;
1469 }
1470 
1471 static const struct cmd cmds[] = {
1472 	{ "show",	do_show },
1473 	{ "list",	do_show },
1474 	{ "help",	do_help },
1475 	{ "dump",	do_dump },
1476 	{ "update",	do_update },
1477 	{ "lookup",	do_lookup },
1478 	{ "getnext",	do_getnext },
1479 	{ "delete",	do_delete },
1480 	{ "pin",	do_pin },
1481 	{ "event_pipe",	do_event_pipe },
1482 	{ "create",	do_create },
1483 	{ "peek",	do_lookup },
1484 	{ "push",	do_update },
1485 	{ "enqueue",	do_update },
1486 	{ "pop",	do_pop_dequeue },
1487 	{ "dequeue",	do_pop_dequeue },
1488 	{ "freeze",	do_freeze },
1489 	{ 0 }
1490 };
1491 
1492 int do_map(int argc, char **argv)
1493 {
1494 	return cmd_select(cmds, argc, argv, do_help);
1495 }
1496