xref: /linux/tools/bpf/bpftool/map.c (revision 60a2f25de7b8b785baee2932db932ae9a5b8c86d)
1 // SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
2 /* Copyright (C) 2017-2018 Netronome Systems, Inc. */
3 
4 #include <errno.h>
5 #include <fcntl.h>
6 #include <linux/err.h>
7 #include <linux/kernel.h>
8 #include <net/if.h>
9 #include <stdbool.h>
10 #include <stdio.h>
11 #include <stdlib.h>
12 #include <string.h>
13 #include <unistd.h>
14 #include <sys/types.h>
15 #include <sys/stat.h>
16 
17 #include <bpf/bpf.h>
18 #include <bpf/btf.h>
19 #include <bpf/hashmap.h>
20 
21 #include "json_writer.h"
22 #include "main.h"
23 
24 static struct hashmap *map_table;
25 
26 static bool map_is_per_cpu(__u32 type)
27 {
28 	return type == BPF_MAP_TYPE_PERCPU_HASH ||
29 	       type == BPF_MAP_TYPE_PERCPU_ARRAY ||
30 	       type == BPF_MAP_TYPE_LRU_PERCPU_HASH ||
31 	       type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE;
32 }
33 
34 static bool map_is_map_of_maps(__u32 type)
35 {
36 	return type == BPF_MAP_TYPE_ARRAY_OF_MAPS ||
37 	       type == BPF_MAP_TYPE_HASH_OF_MAPS;
38 }
39 
40 static bool map_is_map_of_progs(__u32 type)
41 {
42 	return type == BPF_MAP_TYPE_PROG_ARRAY;
43 }
44 
45 static int map_type_from_str(const char *type)
46 {
47 	const char *map_type_str;
48 	unsigned int i;
49 
50 	for (i = 0; ; i++) {
51 		map_type_str = libbpf_bpf_map_type_str(i);
52 		if (!map_type_str)
53 			break;
54 
55 		/* Don't allow prefixing in case of possible future shadowing */
56 		if (!strcmp(map_type_str, type))
57 			return i;
58 	}
59 	return -1;
60 }
61 
62 static void *alloc_value(struct bpf_map_info *info)
63 {
64 	if (map_is_per_cpu(info->type))
65 		return malloc(round_up(info->value_size, 8) *
66 			      get_possible_cpus());
67 	else
68 		return malloc(info->value_size);
69 }
70 
71 static int do_dump_btf(const struct btf_dumper *d,
72 		       struct bpf_map_info *map_info, void *key,
73 		       void *value)
74 {
75 	__u32 value_id;
76 	int ret = 0;
77 
78 	/* start of key-value pair */
79 	jsonw_start_object(d->jw);
80 
81 	if (map_info->btf_key_type_id) {
82 		jsonw_name(d->jw, "key");
83 
84 		ret = btf_dumper_type(d, map_info->btf_key_type_id, key);
85 		if (ret)
86 			goto err_end_obj;
87 	}
88 
89 	value_id = map_info->btf_vmlinux_value_type_id ?
90 		: map_info->btf_value_type_id;
91 
92 	if (!map_is_per_cpu(map_info->type)) {
93 		jsonw_name(d->jw, "value");
94 		ret = btf_dumper_type(d, value_id, value);
95 	} else {
96 		unsigned int i, n, step;
97 
98 		jsonw_name(d->jw, "values");
99 		jsonw_start_array(d->jw);
100 		n = get_possible_cpus();
101 		step = round_up(map_info->value_size, 8);
102 		for (i = 0; i < n; i++) {
103 			jsonw_start_object(d->jw);
104 			jsonw_int_field(d->jw, "cpu", i);
105 			jsonw_name(d->jw, "value");
106 			ret = btf_dumper_type(d, value_id, value + i * step);
107 			jsonw_end_object(d->jw);
108 			if (ret)
109 				break;
110 		}
111 		jsonw_end_array(d->jw);
112 	}
113 
114 err_end_obj:
115 	/* end of key-value pair */
116 	jsonw_end_object(d->jw);
117 
118 	return ret;
119 }
120 
121 static json_writer_t *get_btf_writer(void)
122 {
123 	json_writer_t *jw = jsonw_new(stdout);
124 
125 	if (!jw)
126 		return NULL;
127 	jsonw_pretty(jw, true);
128 
129 	return jw;
130 }
131 
132 static void print_entry_json(struct bpf_map_info *info, unsigned char *key,
133 			     unsigned char *value, struct btf *btf)
134 {
135 	jsonw_start_object(json_wtr);
136 
137 	if (!map_is_per_cpu(info->type)) {
138 		jsonw_name(json_wtr, "key");
139 		print_hex_data_json(key, info->key_size);
140 		jsonw_name(json_wtr, "value");
141 		print_hex_data_json(value, info->value_size);
142 		if (map_is_map_of_maps(info->type))
143 			jsonw_uint_field(json_wtr, "inner_map_id",
144 					 *(unsigned int *)value);
145 		if (btf) {
146 			struct btf_dumper d = {
147 				.btf = btf,
148 				.jw = json_wtr,
149 				.is_plain_text = false,
150 			};
151 
152 			jsonw_name(json_wtr, "formatted");
153 			do_dump_btf(&d, info, key, value);
154 		}
155 	} else {
156 		unsigned int i, n, step;
157 
158 		n = get_possible_cpus();
159 		step = round_up(info->value_size, 8);
160 
161 		jsonw_name(json_wtr, "key");
162 		print_hex_data_json(key, info->key_size);
163 
164 		jsonw_name(json_wtr, "values");
165 		jsonw_start_array(json_wtr);
166 		for (i = 0; i < n; i++) {
167 			jsonw_start_object(json_wtr);
168 
169 			jsonw_int_field(json_wtr, "cpu", i);
170 
171 			jsonw_name(json_wtr, "value");
172 			print_hex_data_json(value + i * step,
173 					    info->value_size);
174 
175 			jsonw_end_object(json_wtr);
176 		}
177 		jsonw_end_array(json_wtr);
178 		if (btf) {
179 			struct btf_dumper d = {
180 				.btf = btf,
181 				.jw = json_wtr,
182 				.is_plain_text = false,
183 			};
184 
185 			jsonw_name(json_wtr, "formatted");
186 			do_dump_btf(&d, info, key, value);
187 		}
188 	}
189 
190 	jsonw_end_object(json_wtr);
191 }
192 
193 static void
194 print_entry_error_msg(struct bpf_map_info *info, unsigned char *key,
195 		      const char *error_msg)
196 {
197 	int msg_size = strlen(error_msg);
198 	bool single_line, break_names;
199 
200 	break_names = info->key_size > 16 || msg_size > 16;
201 	single_line = info->key_size + msg_size <= 24 && !break_names;
202 
203 	printf("key:%c", break_names ? '\n' : ' ');
204 	fprint_hex(stdout, key, info->key_size, " ");
205 
206 	printf(single_line ? "  " : "\n");
207 
208 	printf("value:%c%s", break_names ? '\n' : ' ', error_msg);
209 
210 	printf("\n");
211 }
212 
213 static void
214 print_entry_error(struct bpf_map_info *map_info, void *key, int lookup_errno)
215 {
216 	/* For prog_array maps or arrays of maps, failure to lookup the value
217 	 * means there is no entry for that key. Do not print an error message
218 	 * in that case.
219 	 */
220 	if ((map_is_map_of_maps(map_info->type) ||
221 	     map_is_map_of_progs(map_info->type)) && lookup_errno == ENOENT)
222 		return;
223 
224 	if (json_output) {
225 		jsonw_start_object(json_wtr);	/* entry */
226 		jsonw_name(json_wtr, "key");
227 		print_hex_data_json(key, map_info->key_size);
228 		jsonw_name(json_wtr, "value");
229 		jsonw_start_object(json_wtr);	/* error */
230 		jsonw_string_field(json_wtr, "error", strerror(lookup_errno));
231 		jsonw_end_object(json_wtr);	/* error */
232 		jsonw_end_object(json_wtr);	/* entry */
233 	} else {
234 		const char *msg = NULL;
235 
236 		if (lookup_errno == ENOENT)
237 			msg = "<no entry>";
238 		else if (lookup_errno == ENOSPC &&
239 			 map_info->type == BPF_MAP_TYPE_REUSEPORT_SOCKARRAY)
240 			msg = "<cannot read>";
241 
242 		print_entry_error_msg(map_info, key,
243 				      msg ? : strerror(lookup_errno));
244 	}
245 }
246 
247 static void print_entry_plain(struct bpf_map_info *info, unsigned char *key,
248 			      unsigned char *value)
249 {
250 	if (!map_is_per_cpu(info->type)) {
251 		bool single_line, break_names;
252 
253 		break_names = info->key_size > 16 || info->value_size > 16;
254 		single_line = info->key_size + info->value_size <= 24 &&
255 			!break_names;
256 
257 		if (info->key_size) {
258 			printf("key:%c", break_names ? '\n' : ' ');
259 			fprint_hex(stdout, key, info->key_size, " ");
260 
261 			printf(single_line ? "  " : "\n");
262 		}
263 
264 		if (info->value_size) {
265 			if (map_is_map_of_maps(info->type)) {
266 				printf("inner_map_id:%c", break_names ? '\n' : ' ');
267 				printf("%u ", *(unsigned int *)value);
268 			} else {
269 				printf("value:%c", break_names ? '\n' : ' ');
270 				fprint_hex(stdout, value, info->value_size, " ");
271 			}
272 		}
273 
274 		printf("\n");
275 	} else {
276 		unsigned int i, n, step;
277 
278 		n = get_possible_cpus();
279 		step = round_up(info->value_size, 8);
280 
281 		if (info->key_size) {
282 			printf("key:\n");
283 			fprint_hex(stdout, key, info->key_size, " ");
284 			printf("\n");
285 		}
286 		if (info->value_size) {
287 			for (i = 0; i < n; i++) {
288 				printf("value (CPU %02d):%c",
289 				       i, info->value_size > 16 ? '\n' : ' ');
290 				fprint_hex(stdout, value + i * step,
291 					   info->value_size, " ");
292 				printf("\n");
293 			}
294 		}
295 	}
296 }
297 
298 static char **parse_bytes(char **argv, const char *name, unsigned char *val,
299 			  unsigned int n)
300 {
301 	unsigned int i = 0, base = 0;
302 	char *endptr;
303 
304 	if (is_prefix(*argv, "hex")) {
305 		base = 16;
306 		argv++;
307 	}
308 
309 	while (i < n && argv[i]) {
310 		val[i] = strtoul(argv[i], &endptr, base);
311 		if (*endptr) {
312 			p_err("error parsing byte: %s", argv[i]);
313 			return NULL;
314 		}
315 		i++;
316 	}
317 
318 	if (i != n) {
319 		p_err("%s expected %d bytes got %d", name, n, i);
320 		return NULL;
321 	}
322 
323 	return argv + i;
324 }
325 
326 /* on per cpu maps we must copy the provided value on all value instances */
327 static void fill_per_cpu_value(struct bpf_map_info *info, void *value)
328 {
329 	unsigned int i, n, step;
330 
331 	if (!map_is_per_cpu(info->type))
332 		return;
333 
334 	n = get_possible_cpus();
335 	step = round_up(info->value_size, 8);
336 	for (i = 1; i < n; i++)
337 		memcpy(value + i * step, value, info->value_size);
338 }
339 
340 static int parse_elem(char **argv, struct bpf_map_info *info,
341 		      void *key, void *value, __u32 key_size, __u32 value_size,
342 		      __u32 *flags, __u32 **value_fd)
343 {
344 	if (!*argv) {
345 		if (!key && !value)
346 			return 0;
347 		p_err("did not find %s", key ? "key" : "value");
348 		return -1;
349 	}
350 
351 	if (is_prefix(*argv, "key")) {
352 		if (!key) {
353 			if (key_size)
354 				p_err("duplicate key");
355 			else
356 				p_err("unnecessary key");
357 			return -1;
358 		}
359 
360 		argv = parse_bytes(argv + 1, "key", key, key_size);
361 		if (!argv)
362 			return -1;
363 
364 		return parse_elem(argv, info, NULL, value, key_size, value_size,
365 				  flags, value_fd);
366 	} else if (is_prefix(*argv, "value")) {
367 		int fd;
368 
369 		if (!value) {
370 			if (value_size)
371 				p_err("duplicate value");
372 			else
373 				p_err("unnecessary value");
374 			return -1;
375 		}
376 
377 		argv++;
378 
379 		if (map_is_map_of_maps(info->type)) {
380 			int argc = 2;
381 
382 			if (value_size != 4) {
383 				p_err("value smaller than 4B for map in map?");
384 				return -1;
385 			}
386 			if (!argv[0] || !argv[1]) {
387 				p_err("not enough value arguments for map in map");
388 				return -1;
389 			}
390 
391 			fd = map_parse_fd(&argc, &argv);
392 			if (fd < 0)
393 				return -1;
394 
395 			*value_fd = value;
396 			**value_fd = fd;
397 		} else if (map_is_map_of_progs(info->type)) {
398 			int argc = 2;
399 
400 			if (value_size != 4) {
401 				p_err("value smaller than 4B for map of progs?");
402 				return -1;
403 			}
404 			if (!argv[0] || !argv[1]) {
405 				p_err("not enough value arguments for map of progs");
406 				return -1;
407 			}
408 			if (is_prefix(*argv, "id"))
409 				p_info("Warning: updating program array via MAP_ID, make sure this map is kept open\n"
410 				       "         by some process or pinned otherwise update will be lost");
411 
412 			fd = prog_parse_fd(&argc, &argv);
413 			if (fd < 0)
414 				return -1;
415 
416 			*value_fd = value;
417 			**value_fd = fd;
418 		} else {
419 			argv = parse_bytes(argv, "value", value, value_size);
420 			if (!argv)
421 				return -1;
422 
423 			fill_per_cpu_value(info, value);
424 		}
425 
426 		return parse_elem(argv, info, key, NULL, key_size, value_size,
427 				  flags, NULL);
428 	} else if (is_prefix(*argv, "any") || is_prefix(*argv, "noexist") ||
429 		   is_prefix(*argv, "exist")) {
430 		if (!flags) {
431 			p_err("flags specified multiple times: %s", *argv);
432 			return -1;
433 		}
434 
435 		if (is_prefix(*argv, "any"))
436 			*flags = BPF_ANY;
437 		else if (is_prefix(*argv, "noexist"))
438 			*flags = BPF_NOEXIST;
439 		else if (is_prefix(*argv, "exist"))
440 			*flags = BPF_EXIST;
441 
442 		return parse_elem(argv + 1, info, key, value, key_size,
443 				  value_size, NULL, value_fd);
444 	}
445 
446 	p_err("expected key or value, got: %s", *argv);
447 	return -1;
448 }
449 
450 static void show_map_header_json(struct bpf_map_info *info, json_writer_t *wtr)
451 {
452 	const char *map_type_str;
453 
454 	jsonw_uint_field(wtr, "id", info->id);
455 	map_type_str = libbpf_bpf_map_type_str(info->type);
456 	if (map_type_str)
457 		jsonw_string_field(wtr, "type", map_type_str);
458 	else
459 		jsonw_uint_field(wtr, "type", info->type);
460 
461 	if (*info->name)
462 		jsonw_string_field(wtr, "name", info->name);
463 
464 	jsonw_name(wtr, "flags");
465 	jsonw_printf(wtr, "%d", info->map_flags);
466 }
467 
468 static int show_map_close_json(int fd, struct bpf_map_info *info)
469 {
470 	char *memlock, *frozen_str;
471 	int frozen = 0;
472 
473 	memlock = get_fdinfo(fd, "memlock");
474 	frozen_str = get_fdinfo(fd, "frozen");
475 
476 	jsonw_start_object(json_wtr);
477 
478 	show_map_header_json(info, json_wtr);
479 
480 	print_dev_json(info->ifindex, info->netns_dev, info->netns_ino);
481 
482 	jsonw_uint_field(json_wtr, "bytes_key", info->key_size);
483 	jsonw_uint_field(json_wtr, "bytes_value", info->value_size);
484 	jsonw_uint_field(json_wtr, "max_entries", info->max_entries);
485 
486 	if (memlock)
487 		jsonw_int_field(json_wtr, "bytes_memlock", atoll(memlock));
488 	free(memlock);
489 
490 	if (info->type == BPF_MAP_TYPE_PROG_ARRAY) {
491 		char *owner_prog_type = get_fdinfo(fd, "owner_prog_type");
492 		char *owner_jited = get_fdinfo(fd, "owner_jited");
493 
494 		if (owner_prog_type) {
495 			unsigned int prog_type = atoi(owner_prog_type);
496 			const char *prog_type_str;
497 
498 			prog_type_str = libbpf_bpf_prog_type_str(prog_type);
499 			if (prog_type_str)
500 				jsonw_string_field(json_wtr, "owner_prog_type",
501 						   prog_type_str);
502 			else
503 				jsonw_uint_field(json_wtr, "owner_prog_type",
504 						 prog_type);
505 		}
506 		if (owner_jited)
507 			jsonw_bool_field(json_wtr, "owner_jited",
508 					 !!atoi(owner_jited));
509 
510 		free(owner_prog_type);
511 		free(owner_jited);
512 	}
513 	close(fd);
514 
515 	if (frozen_str) {
516 		frozen = atoi(frozen_str);
517 		free(frozen_str);
518 	}
519 	jsonw_int_field(json_wtr, "frozen", frozen);
520 
521 	if (info->btf_id)
522 		jsonw_int_field(json_wtr, "btf_id", info->btf_id);
523 
524 	if (!hashmap__empty(map_table)) {
525 		struct hashmap_entry *entry;
526 
527 		jsonw_name(json_wtr, "pinned");
528 		jsonw_start_array(json_wtr);
529 		hashmap__for_each_key_entry(map_table, entry, info->id)
530 			jsonw_string(json_wtr, entry->pvalue);
531 		jsonw_end_array(json_wtr);
532 	}
533 
534 	emit_obj_refs_json(refs_table, info->id, json_wtr);
535 
536 	jsonw_end_object(json_wtr);
537 
538 	return 0;
539 }
540 
541 static void show_map_header_plain(struct bpf_map_info *info)
542 {
543 	const char *map_type_str;
544 
545 	printf("%u: ", info->id);
546 
547 	map_type_str = libbpf_bpf_map_type_str(info->type);
548 	if (map_type_str)
549 		printf("%s  ", map_type_str);
550 	else
551 		printf("type %u  ", info->type);
552 
553 	if (*info->name)
554 		printf("name %s  ", info->name);
555 
556 	printf("flags 0x%x", info->map_flags);
557 	print_dev_plain(info->ifindex, info->netns_dev, info->netns_ino);
558 	printf("\n");
559 }
560 
561 static int show_map_close_plain(int fd, struct bpf_map_info *info)
562 {
563 	char *memlock, *frozen_str;
564 	int frozen = 0;
565 
566 	memlock = get_fdinfo(fd, "memlock");
567 	frozen_str = get_fdinfo(fd, "frozen");
568 
569 	show_map_header_plain(info);
570 	printf("\tkey %uB  value %uB  max_entries %u",
571 	       info->key_size, info->value_size, info->max_entries);
572 
573 	if (memlock)
574 		printf("  memlock %sB", memlock);
575 	free(memlock);
576 
577 	if (info->type == BPF_MAP_TYPE_PROG_ARRAY) {
578 		char *owner_prog_type = get_fdinfo(fd, "owner_prog_type");
579 		char *owner_jited = get_fdinfo(fd, "owner_jited");
580 
581 		if (owner_prog_type || owner_jited)
582 			printf("\n\t");
583 		if (owner_prog_type) {
584 			unsigned int prog_type = atoi(owner_prog_type);
585 			const char *prog_type_str;
586 
587 			prog_type_str = libbpf_bpf_prog_type_str(prog_type);
588 			if (prog_type_str)
589 				printf("owner_prog_type %s  ", prog_type_str);
590 			else
591 				printf("owner_prog_type %d  ", prog_type);
592 		}
593 		if (owner_jited)
594 			printf("owner%s jited",
595 			       atoi(owner_jited) ? "" : " not");
596 
597 		free(owner_prog_type);
598 		free(owner_jited);
599 	}
600 	close(fd);
601 
602 	if (!hashmap__empty(map_table)) {
603 		struct hashmap_entry *entry;
604 
605 		hashmap__for_each_key_entry(map_table, entry, info->id)
606 			printf("\n\tpinned %s", (char *)entry->pvalue);
607 	}
608 
609 	if (frozen_str) {
610 		frozen = atoi(frozen_str);
611 		free(frozen_str);
612 	}
613 
614 	if (info->btf_id || frozen)
615 		printf("\n\t");
616 
617 	if (info->btf_id)
618 		printf("btf_id %d", info->btf_id);
619 
620 	if (frozen)
621 		printf("%sfrozen", info->btf_id ? "  " : "");
622 
623 	emit_obj_refs_plain(refs_table, info->id, "\n\tpids ");
624 
625 	printf("\n");
626 	return 0;
627 }
628 
629 static int do_show_subset(int argc, char **argv)
630 {
631 	struct bpf_map_info info = {};
632 	__u32 len = sizeof(info);
633 	int *fds = NULL;
634 	int nb_fds, i;
635 	int err = -1;
636 
637 	fds = malloc(sizeof(int));
638 	if (!fds) {
639 		p_err("mem alloc failed");
640 		return -1;
641 	}
642 	nb_fds = map_parse_fds(&argc, &argv, &fds);
643 	if (nb_fds < 1)
644 		goto exit_free;
645 
646 	if (json_output && nb_fds > 1)
647 		jsonw_start_array(json_wtr);	/* root array */
648 	for (i = 0; i < nb_fds; i++) {
649 		err = bpf_map_get_info_by_fd(fds[i], &info, &len);
650 		if (err) {
651 			p_err("can't get map info: %s",
652 			      strerror(errno));
653 			for (; i < nb_fds; i++)
654 				close(fds[i]);
655 			break;
656 		}
657 
658 		if (json_output)
659 			show_map_close_json(fds[i], &info);
660 		else
661 			show_map_close_plain(fds[i], &info);
662 
663 		close(fds[i]);
664 	}
665 	if (json_output && nb_fds > 1)
666 		jsonw_end_array(json_wtr);	/* root array */
667 
668 exit_free:
669 	free(fds);
670 	return err;
671 }
672 
673 static int do_show(int argc, char **argv)
674 {
675 	struct bpf_map_info info = {};
676 	__u32 len = sizeof(info);
677 	__u32 id = 0;
678 	int err;
679 	int fd;
680 
681 	if (show_pinned) {
682 		map_table = hashmap__new(hash_fn_for_key_as_id,
683 					 equal_fn_for_key_as_id, NULL);
684 		if (IS_ERR(map_table)) {
685 			p_err("failed to create hashmap for pinned paths");
686 			return -1;
687 		}
688 		build_pinned_obj_table(map_table, BPF_OBJ_MAP);
689 	}
690 	build_obj_refs_table(&refs_table, BPF_OBJ_MAP);
691 
692 	if (argc == 2)
693 		return do_show_subset(argc, argv);
694 
695 	if (argc)
696 		return BAD_ARG();
697 
698 	if (json_output)
699 		jsonw_start_array(json_wtr);
700 	while (true) {
701 		err = bpf_map_get_next_id(id, &id);
702 		if (err) {
703 			if (errno == ENOENT)
704 				break;
705 			p_err("can't get next map: %s%s", strerror(errno),
706 			      errno == EINVAL ? " -- kernel too old?" : "");
707 			break;
708 		}
709 
710 		fd = bpf_map_get_fd_by_id(id);
711 		if (fd < 0) {
712 			if (errno == ENOENT)
713 				continue;
714 			p_err("can't get map by id (%u): %s",
715 			      id, strerror(errno));
716 			break;
717 		}
718 
719 		err = bpf_map_get_info_by_fd(fd, &info, &len);
720 		if (err) {
721 			p_err("can't get map info: %s", strerror(errno));
722 			close(fd);
723 			break;
724 		}
725 
726 		if (json_output)
727 			show_map_close_json(fd, &info);
728 		else
729 			show_map_close_plain(fd, &info);
730 	}
731 	if (json_output)
732 		jsonw_end_array(json_wtr);
733 
734 	delete_obj_refs_table(refs_table);
735 
736 	if (show_pinned)
737 		delete_pinned_obj_table(map_table);
738 
739 	return errno == ENOENT ? 0 : -1;
740 }
741 
742 static int dump_map_elem(int fd, void *key, void *value,
743 			 struct bpf_map_info *map_info, struct btf *btf,
744 			 json_writer_t *btf_wtr)
745 {
746 	if (bpf_map_lookup_elem(fd, key, value)) {
747 		print_entry_error(map_info, key, errno);
748 		return -1;
749 	}
750 
751 	if (json_output) {
752 		print_entry_json(map_info, key, value, btf);
753 	} else if (btf) {
754 		struct btf_dumper d = {
755 			.btf = btf,
756 			.jw = btf_wtr,
757 			.is_plain_text = true,
758 		};
759 
760 		do_dump_btf(&d, map_info, key, value);
761 	} else {
762 		print_entry_plain(map_info, key, value);
763 	}
764 
765 	return 0;
766 }
767 
768 static int maps_have_btf(int *fds, int nb_fds)
769 {
770 	struct bpf_map_info info = {};
771 	__u32 len = sizeof(info);
772 	int err, i;
773 
774 	for (i = 0; i < nb_fds; i++) {
775 		err = bpf_map_get_info_by_fd(fds[i], &info, &len);
776 		if (err) {
777 			p_err("can't get map info: %s", strerror(errno));
778 			return -1;
779 		}
780 
781 		if (!info.btf_id)
782 			return 0;
783 	}
784 
785 	return 1;
786 }
787 
788 static struct btf *btf_vmlinux;
789 
790 static int get_map_kv_btf(const struct bpf_map_info *info, struct btf **btf)
791 {
792 	int err = 0;
793 
794 	if (info->btf_vmlinux_value_type_id) {
795 		if (!btf_vmlinux) {
796 			btf_vmlinux = libbpf_find_kernel_btf();
797 			if (!btf_vmlinux) {
798 				p_err("failed to get kernel btf");
799 				return -errno;
800 			}
801 		}
802 		*btf = btf_vmlinux;
803 	} else if (info->btf_value_type_id) {
804 		*btf = btf__load_from_kernel_by_id(info->btf_id);
805 		if (!*btf) {
806 			err = -errno;
807 			p_err("failed to get btf");
808 		}
809 	} else {
810 		*btf = NULL;
811 	}
812 
813 	return err;
814 }
815 
816 static void free_map_kv_btf(struct btf *btf)
817 {
818 	if (btf != btf_vmlinux)
819 		btf__free(btf);
820 }
821 
822 static int
823 map_dump(int fd, struct bpf_map_info *info, json_writer_t *wtr,
824 	 bool show_header)
825 {
826 	void *key, *value, *prev_key;
827 	unsigned int num_elems = 0;
828 	struct btf *btf = NULL;
829 	int err;
830 
831 	key = malloc(info->key_size);
832 	value = alloc_value(info);
833 	if (!key || !value) {
834 		p_err("mem alloc failed");
835 		err = -1;
836 		goto exit_free;
837 	}
838 
839 	prev_key = NULL;
840 
841 	if (wtr) {
842 		err = get_map_kv_btf(info, &btf);
843 		if (err) {
844 			goto exit_free;
845 		}
846 
847 		if (show_header) {
848 			jsonw_start_object(wtr);	/* map object */
849 			show_map_header_json(info, wtr);
850 			jsonw_name(wtr, "elements");
851 		}
852 		jsonw_start_array(wtr);		/* elements */
853 	} else if (show_header) {
854 		show_map_header_plain(info);
855 	}
856 
857 	if (info->type == BPF_MAP_TYPE_REUSEPORT_SOCKARRAY &&
858 	    info->value_size != 8) {
859 		const char *map_type_str;
860 
861 		map_type_str = libbpf_bpf_map_type_str(info->type);
862 		p_info("Warning: cannot read values from %s map with value_size != 8",
863 		       map_type_str);
864 	}
865 	while (true) {
866 		err = bpf_map_get_next_key(fd, prev_key, key);
867 		if (err) {
868 			if (errno == ENOENT)
869 				err = 0;
870 			break;
871 		}
872 		if (!dump_map_elem(fd, key, value, info, btf, wtr))
873 			num_elems++;
874 		prev_key = key;
875 	}
876 
877 	if (wtr) {
878 		jsonw_end_array(wtr);	/* elements */
879 		if (show_header)
880 			jsonw_end_object(wtr);	/* map object */
881 	} else {
882 		printf("Found %u element%s\n", num_elems,
883 		       num_elems != 1 ? "s" : "");
884 	}
885 
886 exit_free:
887 	free(key);
888 	free(value);
889 	close(fd);
890 	free_map_kv_btf(btf);
891 
892 	return err;
893 }
894 
895 static int do_dump(int argc, char **argv)
896 {
897 	json_writer_t *wtr = NULL, *btf_wtr = NULL;
898 	struct bpf_map_info info = {};
899 	int nb_fds, i = 0;
900 	__u32 len = sizeof(info);
901 	int *fds = NULL;
902 	int err = -1;
903 
904 	if (argc != 2)
905 		usage();
906 
907 	fds = malloc(sizeof(int));
908 	if (!fds) {
909 		p_err("mem alloc failed");
910 		return -1;
911 	}
912 	nb_fds = map_parse_fds(&argc, &argv, &fds);
913 	if (nb_fds < 1)
914 		goto exit_free;
915 
916 	if (json_output) {
917 		wtr = json_wtr;
918 	} else {
919 		int do_plain_btf;
920 
921 		do_plain_btf = maps_have_btf(fds, nb_fds);
922 		if (do_plain_btf < 0)
923 			goto exit_close;
924 
925 		if (do_plain_btf) {
926 			btf_wtr = get_btf_writer();
927 			wtr = btf_wtr;
928 			if (!btf_wtr)
929 				p_info("failed to create json writer for btf. falling back to plain output");
930 		}
931 	}
932 
933 	if (wtr && nb_fds > 1)
934 		jsonw_start_array(wtr);	/* root array */
935 	for (i = 0; i < nb_fds; i++) {
936 		if (bpf_map_get_info_by_fd(fds[i], &info, &len)) {
937 			p_err("can't get map info: %s", strerror(errno));
938 			break;
939 		}
940 		err = map_dump(fds[i], &info, wtr, nb_fds > 1);
941 		if (!wtr && i != nb_fds - 1)
942 			printf("\n");
943 
944 		if (err)
945 			break;
946 		close(fds[i]);
947 	}
948 	if (wtr && nb_fds > 1)
949 		jsonw_end_array(wtr);	/* root array */
950 
951 	if (btf_wtr)
952 		jsonw_destroy(&btf_wtr);
953 exit_close:
954 	for (; i < nb_fds; i++)
955 		close(fds[i]);
956 exit_free:
957 	free(fds);
958 	btf__free(btf_vmlinux);
959 	return err;
960 }
961 
962 static int alloc_key_value(struct bpf_map_info *info, void **key, void **value)
963 {
964 	*key = NULL;
965 	*value = NULL;
966 
967 	if (info->key_size) {
968 		*key = malloc(info->key_size);
969 		if (!*key) {
970 			p_err("key mem alloc failed");
971 			return -1;
972 		}
973 	}
974 
975 	if (info->value_size) {
976 		*value = alloc_value(info);
977 		if (!*value) {
978 			p_err("value mem alloc failed");
979 			free(*key);
980 			*key = NULL;
981 			return -1;
982 		}
983 	}
984 
985 	return 0;
986 }
987 
988 static int do_update(int argc, char **argv)
989 {
990 	struct bpf_map_info info = {};
991 	__u32 len = sizeof(info);
992 	__u32 *value_fd = NULL;
993 	__u32 flags = BPF_ANY;
994 	void *key, *value;
995 	int fd, err;
996 
997 	if (argc < 2)
998 		usage();
999 
1000 	fd = map_parse_fd_and_info(&argc, &argv, &info, &len);
1001 	if (fd < 0)
1002 		return -1;
1003 
1004 	err = alloc_key_value(&info, &key, &value);
1005 	if (err)
1006 		goto exit_free;
1007 
1008 	err = parse_elem(argv, &info, key, value, info.key_size,
1009 			 info.value_size, &flags, &value_fd);
1010 	if (err)
1011 		goto exit_free;
1012 
1013 	err = bpf_map_update_elem(fd, key, value, flags);
1014 	if (err) {
1015 		p_err("update failed: %s", strerror(errno));
1016 		goto exit_free;
1017 	}
1018 
1019 exit_free:
1020 	if (value_fd)
1021 		close(*value_fd);
1022 	free(key);
1023 	free(value);
1024 	close(fd);
1025 
1026 	if (!err && json_output)
1027 		jsonw_null(json_wtr);
1028 	return err;
1029 }
1030 
1031 static void print_key_value(struct bpf_map_info *info, void *key,
1032 			    void *value)
1033 {
1034 	json_writer_t *btf_wtr;
1035 	struct btf *btf;
1036 
1037 	if (get_map_kv_btf(info, &btf))
1038 		return;
1039 
1040 	if (json_output) {
1041 		print_entry_json(info, key, value, btf);
1042 	} else if (btf) {
1043 		/* if here json_wtr wouldn't have been initialised,
1044 		 * so let's create separate writer for btf
1045 		 */
1046 		btf_wtr = get_btf_writer();
1047 		if (!btf_wtr) {
1048 			p_info("failed to create json writer for btf. falling back to plain output");
1049 			btf__free(btf);
1050 			btf = NULL;
1051 			print_entry_plain(info, key, value);
1052 		} else {
1053 			struct btf_dumper d = {
1054 				.btf = btf,
1055 				.jw = btf_wtr,
1056 				.is_plain_text = true,
1057 			};
1058 
1059 			do_dump_btf(&d, info, key, value);
1060 			jsonw_destroy(&btf_wtr);
1061 		}
1062 	} else {
1063 		print_entry_plain(info, key, value);
1064 	}
1065 	btf__free(btf);
1066 }
1067 
1068 static int do_lookup(int argc, char **argv)
1069 {
1070 	struct bpf_map_info info = {};
1071 	__u32 len = sizeof(info);
1072 	void *key, *value;
1073 	int err;
1074 	int fd;
1075 
1076 	if (argc < 2)
1077 		usage();
1078 
1079 	fd = map_parse_fd_and_info(&argc, &argv, &info, &len);
1080 	if (fd < 0)
1081 		return -1;
1082 
1083 	err = alloc_key_value(&info, &key, &value);
1084 	if (err)
1085 		goto exit_free;
1086 
1087 	err = parse_elem(argv, &info, key, NULL, info.key_size, 0, NULL, NULL);
1088 	if (err)
1089 		goto exit_free;
1090 
1091 	err = bpf_map_lookup_elem(fd, key, value);
1092 	if (err) {
1093 		if (errno == ENOENT) {
1094 			if (json_output) {
1095 				jsonw_null(json_wtr);
1096 			} else {
1097 				printf("key:\n");
1098 				fprint_hex(stdout, key, info.key_size, " ");
1099 				printf("\n\nNot found\n");
1100 			}
1101 		} else {
1102 			p_err("lookup failed: %s", strerror(errno));
1103 		}
1104 
1105 		goto exit_free;
1106 	}
1107 
1108 	/* here means bpf_map_lookup_elem() succeeded */
1109 	print_key_value(&info, key, value);
1110 
1111 exit_free:
1112 	free(key);
1113 	free(value);
1114 	close(fd);
1115 
1116 	return err;
1117 }
1118 
1119 static int do_getnext(int argc, char **argv)
1120 {
1121 	struct bpf_map_info info = {};
1122 	__u32 len = sizeof(info);
1123 	void *key, *nextkey;
1124 	int err;
1125 	int fd;
1126 
1127 	if (argc < 2)
1128 		usage();
1129 
1130 	fd = map_parse_fd_and_info(&argc, &argv, &info, &len);
1131 	if (fd < 0)
1132 		return -1;
1133 
1134 	key = malloc(info.key_size);
1135 	nextkey = malloc(info.key_size);
1136 	if (!key || !nextkey) {
1137 		p_err("mem alloc failed");
1138 		err = -1;
1139 		goto exit_free;
1140 	}
1141 
1142 	if (argc) {
1143 		err = parse_elem(argv, &info, key, NULL, info.key_size, 0,
1144 				 NULL, NULL);
1145 		if (err)
1146 			goto exit_free;
1147 	} else {
1148 		free(key);
1149 		key = NULL;
1150 	}
1151 
1152 	err = bpf_map_get_next_key(fd, key, nextkey);
1153 	if (err) {
1154 		p_err("can't get next key: %s", strerror(errno));
1155 		goto exit_free;
1156 	}
1157 
1158 	if (json_output) {
1159 		jsonw_start_object(json_wtr);
1160 		if (key) {
1161 			jsonw_name(json_wtr, "key");
1162 			print_hex_data_json(key, info.key_size);
1163 		} else {
1164 			jsonw_null_field(json_wtr, "key");
1165 		}
1166 		jsonw_name(json_wtr, "next_key");
1167 		print_hex_data_json(nextkey, info.key_size);
1168 		jsonw_end_object(json_wtr);
1169 	} else {
1170 		if (key) {
1171 			printf("key:\n");
1172 			fprint_hex(stdout, key, info.key_size, " ");
1173 			printf("\n");
1174 		} else {
1175 			printf("key: None\n");
1176 		}
1177 		printf("next key:\n");
1178 		fprint_hex(stdout, nextkey, info.key_size, " ");
1179 		printf("\n");
1180 	}
1181 
1182 exit_free:
1183 	free(nextkey);
1184 	free(key);
1185 	close(fd);
1186 
1187 	return err;
1188 }
1189 
1190 static int do_delete(int argc, char **argv)
1191 {
1192 	struct bpf_map_info info = {};
1193 	__u32 len = sizeof(info);
1194 	void *key;
1195 	int err;
1196 	int fd;
1197 
1198 	if (argc < 2)
1199 		usage();
1200 
1201 	fd = map_parse_fd_and_info(&argc, &argv, &info, &len);
1202 	if (fd < 0)
1203 		return -1;
1204 
1205 	key = malloc(info.key_size);
1206 	if (!key) {
1207 		p_err("mem alloc failed");
1208 		err = -1;
1209 		goto exit_free;
1210 	}
1211 
1212 	err = parse_elem(argv, &info, key, NULL, info.key_size, 0, NULL, NULL);
1213 	if (err)
1214 		goto exit_free;
1215 
1216 	err = bpf_map_delete_elem(fd, key);
1217 	if (err)
1218 		p_err("delete failed: %s", strerror(errno));
1219 
1220 exit_free:
1221 	free(key);
1222 	close(fd);
1223 
1224 	if (!err && json_output)
1225 		jsonw_null(json_wtr);
1226 	return err;
1227 }
1228 
1229 static int do_pin(int argc, char **argv)
1230 {
1231 	int err;
1232 
1233 	err = do_pin_any(argc, argv, map_parse_fd);
1234 	if (!err && json_output)
1235 		jsonw_null(json_wtr);
1236 	return err;
1237 }
1238 
1239 static int do_create(int argc, char **argv)
1240 {
1241 	LIBBPF_OPTS(bpf_map_create_opts, attr);
1242 	enum bpf_map_type map_type = BPF_MAP_TYPE_UNSPEC;
1243 	__u32 key_size = 0, value_size = 0, max_entries = 0;
1244 	const char *map_name = NULL;
1245 	const char *pinfile;
1246 	int err = -1, fd;
1247 
1248 	if (!REQ_ARGS(7))
1249 		return -1;
1250 	pinfile = GET_ARG();
1251 
1252 	while (argc) {
1253 		if (!REQ_ARGS(2))
1254 			return -1;
1255 
1256 		if (is_prefix(*argv, "type")) {
1257 			NEXT_ARG();
1258 
1259 			if (map_type) {
1260 				p_err("map type already specified");
1261 				goto exit;
1262 			}
1263 
1264 			map_type = map_type_from_str(*argv);
1265 			if ((int)map_type < 0) {
1266 				p_err("unrecognized map type: %s", *argv);
1267 				goto exit;
1268 			}
1269 			NEXT_ARG();
1270 		} else if (is_prefix(*argv, "name")) {
1271 			NEXT_ARG();
1272 			map_name = GET_ARG();
1273 		} else if (is_prefix(*argv, "key")) {
1274 			if (parse_u32_arg(&argc, &argv, &key_size,
1275 					  "key size"))
1276 				goto exit;
1277 		} else if (is_prefix(*argv, "value")) {
1278 			if (parse_u32_arg(&argc, &argv, &value_size,
1279 					  "value size"))
1280 				goto exit;
1281 		} else if (is_prefix(*argv, "entries")) {
1282 			if (parse_u32_arg(&argc, &argv, &max_entries,
1283 					  "max entries"))
1284 				goto exit;
1285 		} else if (is_prefix(*argv, "flags")) {
1286 			if (parse_u32_arg(&argc, &argv, &attr.map_flags,
1287 					  "flags"))
1288 				goto exit;
1289 		} else if (is_prefix(*argv, "dev")) {
1290 			p_info("Warning: 'bpftool map create [...] dev <ifname>' syntax is deprecated.\n"
1291 			       "Going further, please use 'offload_dev <ifname>' to request hardware offload for the map.");
1292 			goto offload_dev;
1293 		} else if (is_prefix(*argv, "offload_dev")) {
1294 offload_dev:
1295 			NEXT_ARG();
1296 
1297 			if (attr.map_ifindex) {
1298 				p_err("offload device already specified");
1299 				goto exit;
1300 			}
1301 
1302 			attr.map_ifindex = if_nametoindex(*argv);
1303 			if (!attr.map_ifindex) {
1304 				p_err("unrecognized netdevice '%s': %s",
1305 				      *argv, strerror(errno));
1306 				goto exit;
1307 			}
1308 			NEXT_ARG();
1309 		} else if (is_prefix(*argv, "inner_map")) {
1310 			struct bpf_map_info info = {};
1311 			__u32 len = sizeof(info);
1312 			int inner_map_fd;
1313 
1314 			NEXT_ARG();
1315 			if (!REQ_ARGS(2))
1316 				usage();
1317 			inner_map_fd = map_parse_fd_and_info(&argc, &argv,
1318 							     &info, &len);
1319 			if (inner_map_fd < 0)
1320 				return -1;
1321 			attr.inner_map_fd = inner_map_fd;
1322 		} else {
1323 			p_err("unknown arg %s", *argv);
1324 			goto exit;
1325 		}
1326 	}
1327 
1328 	if (!map_name) {
1329 		p_err("map name not specified");
1330 		goto exit;
1331 	}
1332 
1333 	set_max_rlimit();
1334 
1335 	fd = bpf_map_create(map_type, map_name, key_size, value_size, max_entries, &attr);
1336 	if (fd < 0) {
1337 		p_err("map create failed: %s", strerror(errno));
1338 		goto exit;
1339 	}
1340 
1341 	err = do_pin_fd(fd, pinfile);
1342 	close(fd);
1343 	if (err)
1344 		goto exit;
1345 
1346 	if (json_output)
1347 		jsonw_null(json_wtr);
1348 
1349 exit:
1350 	if (attr.inner_map_fd > 0)
1351 		close(attr.inner_map_fd);
1352 
1353 	return err;
1354 }
1355 
1356 static int do_pop_dequeue(int argc, char **argv)
1357 {
1358 	struct bpf_map_info info = {};
1359 	__u32 len = sizeof(info);
1360 	void *key, *value;
1361 	int err;
1362 	int fd;
1363 
1364 	if (argc < 2)
1365 		usage();
1366 
1367 	fd = map_parse_fd_and_info(&argc, &argv, &info, &len);
1368 	if (fd < 0)
1369 		return -1;
1370 
1371 	err = alloc_key_value(&info, &key, &value);
1372 	if (err)
1373 		goto exit_free;
1374 
1375 	err = bpf_map_lookup_and_delete_elem(fd, key, value);
1376 	if (err) {
1377 		if (errno == ENOENT) {
1378 			if (json_output)
1379 				jsonw_null(json_wtr);
1380 			else
1381 				printf("Error: empty map\n");
1382 		} else {
1383 			p_err("pop failed: %s", strerror(errno));
1384 		}
1385 
1386 		goto exit_free;
1387 	}
1388 
1389 	print_key_value(&info, key, value);
1390 
1391 exit_free:
1392 	free(key);
1393 	free(value);
1394 	close(fd);
1395 
1396 	return err;
1397 }
1398 
1399 static int do_freeze(int argc, char **argv)
1400 {
1401 	int err, fd;
1402 
1403 	if (!REQ_ARGS(2))
1404 		return -1;
1405 
1406 	fd = map_parse_fd(&argc, &argv);
1407 	if (fd < 0)
1408 		return -1;
1409 
1410 	if (argc) {
1411 		close(fd);
1412 		return BAD_ARG();
1413 	}
1414 
1415 	err = bpf_map_freeze(fd);
1416 	close(fd);
1417 	if (err) {
1418 		p_err("failed to freeze map: %s", strerror(errno));
1419 		return err;
1420 	}
1421 
1422 	if (json_output)
1423 		jsonw_null(json_wtr);
1424 
1425 	return 0;
1426 }
1427 
1428 static int do_help(int argc, char **argv)
1429 {
1430 	if (json_output) {
1431 		jsonw_null(json_wtr);
1432 		return 0;
1433 	}
1434 
1435 	fprintf(stderr,
1436 		"Usage: %1$s %2$s { show | list }   [MAP]\n"
1437 		"       %1$s %2$s create     FILE type TYPE key KEY_SIZE value VALUE_SIZE \\\n"
1438 		"                                  entries MAX_ENTRIES name NAME [flags FLAGS] \\\n"
1439 		"                                  [inner_map MAP] [offload_dev NAME]\n"
1440 		"       %1$s %2$s dump       MAP\n"
1441 		"       %1$s %2$s update     MAP [key DATA] [value VALUE] [UPDATE_FLAGS]\n"
1442 		"       %1$s %2$s lookup     MAP [key DATA]\n"
1443 		"       %1$s %2$s getnext    MAP [key DATA]\n"
1444 		"       %1$s %2$s delete     MAP  key DATA\n"
1445 		"       %1$s %2$s pin        MAP  FILE\n"
1446 		"       %1$s %2$s event_pipe MAP [cpu N index M]\n"
1447 		"       %1$s %2$s peek       MAP\n"
1448 		"       %1$s %2$s push       MAP value VALUE\n"
1449 		"       %1$s %2$s pop        MAP\n"
1450 		"       %1$s %2$s enqueue    MAP value VALUE\n"
1451 		"       %1$s %2$s dequeue    MAP\n"
1452 		"       %1$s %2$s freeze     MAP\n"
1453 		"       %1$s %2$s help\n"
1454 		"\n"
1455 		"       " HELP_SPEC_MAP "\n"
1456 		"       DATA := { [hex] BYTES }\n"
1457 		"       " HELP_SPEC_PROGRAM "\n"
1458 		"       VALUE := { DATA | MAP | PROG }\n"
1459 		"       UPDATE_FLAGS := { any | exist | noexist }\n"
1460 		"       TYPE := { hash | array | prog_array | perf_event_array | percpu_hash |\n"
1461 		"                 percpu_array | stack_trace | cgroup_array | lru_hash |\n"
1462 		"                 lru_percpu_hash | lpm_trie | array_of_maps | hash_of_maps |\n"
1463 		"                 devmap | devmap_hash | sockmap | cpumap | xskmap | sockhash |\n"
1464 		"                 cgroup_storage | reuseport_sockarray | percpu_cgroup_storage |\n"
1465 		"                 queue | stack | sk_storage | struct_ops | ringbuf | inode_storage |\n"
1466 		"                 task_storage | bloom_filter | user_ringbuf | cgrp_storage | arena }\n"
1467 		"       " HELP_SPEC_OPTIONS " |\n"
1468 		"                    {-f|--bpffs} | {-n|--nomount} }\n"
1469 		"",
1470 		bin_name, argv[-2]);
1471 
1472 	return 0;
1473 }
1474 
1475 static const struct cmd cmds[] = {
1476 	{ "show",	do_show },
1477 	{ "list",	do_show },
1478 	{ "help",	do_help },
1479 	{ "dump",	do_dump },
1480 	{ "update",	do_update },
1481 	{ "lookup",	do_lookup },
1482 	{ "getnext",	do_getnext },
1483 	{ "delete",	do_delete },
1484 	{ "pin",	do_pin },
1485 	{ "event_pipe",	do_event_pipe },
1486 	{ "create",	do_create },
1487 	{ "peek",	do_lookup },
1488 	{ "push",	do_update },
1489 	{ "enqueue",	do_update },
1490 	{ "pop",	do_pop_dequeue },
1491 	{ "dequeue",	do_pop_dequeue },
1492 	{ "freeze",	do_freeze },
1493 	{ 0 }
1494 };
1495 
1496 int do_map(int argc, char **argv)
1497 {
1498 	return cmd_select(cmds, argc, argv, do_help);
1499 }
1500