xref: /openbmc/linux/tools/bpf/bpftool/map.c (revision 38f0408e)
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 (btf) {
143 			struct btf_dumper d = {
144 				.btf = btf,
145 				.jw = json_wtr,
146 				.is_plain_text = false,
147 			};
148 
149 			jsonw_name(json_wtr, "formatted");
150 			do_dump_btf(&d, info, key, value);
151 		}
152 	} else {
153 		unsigned int i, n, step;
154 
155 		n = get_possible_cpus();
156 		step = round_up(info->value_size, 8);
157 
158 		jsonw_name(json_wtr, "key");
159 		print_hex_data_json(key, info->key_size);
160 
161 		jsonw_name(json_wtr, "values");
162 		jsonw_start_array(json_wtr);
163 		for (i = 0; i < n; i++) {
164 			jsonw_start_object(json_wtr);
165 
166 			jsonw_int_field(json_wtr, "cpu", i);
167 
168 			jsonw_name(json_wtr, "value");
169 			print_hex_data_json(value + i * step,
170 					    info->value_size);
171 
172 			jsonw_end_object(json_wtr);
173 		}
174 		jsonw_end_array(json_wtr);
175 		if (btf) {
176 			struct btf_dumper d = {
177 				.btf = btf,
178 				.jw = json_wtr,
179 				.is_plain_text = false,
180 			};
181 
182 			jsonw_name(json_wtr, "formatted");
183 			do_dump_btf(&d, info, key, value);
184 		}
185 	}
186 
187 	jsonw_end_object(json_wtr);
188 }
189 
190 static void
191 print_entry_error_msg(struct bpf_map_info *info, unsigned char *key,
192 		      const char *error_msg)
193 {
194 	int msg_size = strlen(error_msg);
195 	bool single_line, break_names;
196 
197 	break_names = info->key_size > 16 || msg_size > 16;
198 	single_line = info->key_size + msg_size <= 24 && !break_names;
199 
200 	printf("key:%c", break_names ? '\n' : ' ');
201 	fprint_hex(stdout, key, info->key_size, " ");
202 
203 	printf(single_line ? "  " : "\n");
204 
205 	printf("value:%c%s", break_names ? '\n' : ' ', error_msg);
206 
207 	printf("\n");
208 }
209 
210 static void
211 print_entry_error(struct bpf_map_info *map_info, void *key, int lookup_errno)
212 {
213 	/* For prog_array maps or arrays of maps, failure to lookup the value
214 	 * means there is no entry for that key. Do not print an error message
215 	 * in that case.
216 	 */
217 	if ((map_is_map_of_maps(map_info->type) ||
218 	     map_is_map_of_progs(map_info->type)) && lookup_errno == ENOENT)
219 		return;
220 
221 	if (json_output) {
222 		jsonw_start_object(json_wtr);	/* entry */
223 		jsonw_name(json_wtr, "key");
224 		print_hex_data_json(key, map_info->key_size);
225 		jsonw_name(json_wtr, "value");
226 		jsonw_start_object(json_wtr);	/* error */
227 		jsonw_string_field(json_wtr, "error", strerror(lookup_errno));
228 		jsonw_end_object(json_wtr);	/* error */
229 		jsonw_end_object(json_wtr);	/* entry */
230 	} else {
231 		const char *msg = NULL;
232 
233 		if (lookup_errno == ENOENT)
234 			msg = "<no entry>";
235 		else if (lookup_errno == ENOSPC &&
236 			 map_info->type == BPF_MAP_TYPE_REUSEPORT_SOCKARRAY)
237 			msg = "<cannot read>";
238 
239 		print_entry_error_msg(map_info, key,
240 				      msg ? : strerror(lookup_errno));
241 	}
242 }
243 
244 static void print_entry_plain(struct bpf_map_info *info, unsigned char *key,
245 			      unsigned char *value)
246 {
247 	if (!map_is_per_cpu(info->type)) {
248 		bool single_line, break_names;
249 
250 		break_names = info->key_size > 16 || info->value_size > 16;
251 		single_line = info->key_size + info->value_size <= 24 &&
252 			!break_names;
253 
254 		if (info->key_size) {
255 			printf("key:%c", break_names ? '\n' : ' ');
256 			fprint_hex(stdout, key, info->key_size, " ");
257 
258 			printf(single_line ? "  " : "\n");
259 		}
260 
261 		if (info->value_size) {
262 			printf("value:%c", break_names ? '\n' : ' ');
263 			fprint_hex(stdout, value, info->value_size, " ");
264 		}
265 
266 		printf("\n");
267 	} else {
268 		unsigned int i, n, step;
269 
270 		n = get_possible_cpus();
271 		step = round_up(info->value_size, 8);
272 
273 		if (info->key_size) {
274 			printf("key:\n");
275 			fprint_hex(stdout, key, info->key_size, " ");
276 			printf("\n");
277 		}
278 		if (info->value_size) {
279 			for (i = 0; i < n; i++) {
280 				printf("value (CPU %02d):%c",
281 				       i, info->value_size > 16 ? '\n' : ' ');
282 				fprint_hex(stdout, value + i * step,
283 					   info->value_size, " ");
284 				printf("\n");
285 			}
286 		}
287 	}
288 }
289 
290 static char **parse_bytes(char **argv, const char *name, unsigned char *val,
291 			  unsigned int n)
292 {
293 	unsigned int i = 0, base = 0;
294 	char *endptr;
295 
296 	if (is_prefix(*argv, "hex")) {
297 		base = 16;
298 		argv++;
299 	}
300 
301 	while (i < n && argv[i]) {
302 		val[i] = strtoul(argv[i], &endptr, base);
303 		if (*endptr) {
304 			p_err("error parsing byte: %s", argv[i]);
305 			return NULL;
306 		}
307 		i++;
308 	}
309 
310 	if (i != n) {
311 		p_err("%s expected %d bytes got %d", name, n, i);
312 		return NULL;
313 	}
314 
315 	return argv + i;
316 }
317 
318 /* on per cpu maps we must copy the provided value on all value instances */
319 static void fill_per_cpu_value(struct bpf_map_info *info, void *value)
320 {
321 	unsigned int i, n, step;
322 
323 	if (!map_is_per_cpu(info->type))
324 		return;
325 
326 	n = get_possible_cpus();
327 	step = round_up(info->value_size, 8);
328 	for (i = 1; i < n; i++)
329 		memcpy(value + i * step, value, info->value_size);
330 }
331 
332 static int parse_elem(char **argv, struct bpf_map_info *info,
333 		      void *key, void *value, __u32 key_size, __u32 value_size,
334 		      __u32 *flags, __u32 **value_fd)
335 {
336 	if (!*argv) {
337 		if (!key && !value)
338 			return 0;
339 		p_err("did not find %s", key ? "key" : "value");
340 		return -1;
341 	}
342 
343 	if (is_prefix(*argv, "key")) {
344 		if (!key) {
345 			if (key_size)
346 				p_err("duplicate key");
347 			else
348 				p_err("unnecessary key");
349 			return -1;
350 		}
351 
352 		argv = parse_bytes(argv + 1, "key", key, key_size);
353 		if (!argv)
354 			return -1;
355 
356 		return parse_elem(argv, info, NULL, value, key_size, value_size,
357 				  flags, value_fd);
358 	} else if (is_prefix(*argv, "value")) {
359 		int fd;
360 
361 		if (!value) {
362 			if (value_size)
363 				p_err("duplicate value");
364 			else
365 				p_err("unnecessary value");
366 			return -1;
367 		}
368 
369 		argv++;
370 
371 		if (map_is_map_of_maps(info->type)) {
372 			int argc = 2;
373 
374 			if (value_size != 4) {
375 				p_err("value smaller than 4B for map in map?");
376 				return -1;
377 			}
378 			if (!argv[0] || !argv[1]) {
379 				p_err("not enough value arguments for map in map");
380 				return -1;
381 			}
382 
383 			fd = map_parse_fd(&argc, &argv);
384 			if (fd < 0)
385 				return -1;
386 
387 			*value_fd = value;
388 			**value_fd = fd;
389 		} else if (map_is_map_of_progs(info->type)) {
390 			int argc = 2;
391 
392 			if (value_size != 4) {
393 				p_err("value smaller than 4B for map of progs?");
394 				return -1;
395 			}
396 			if (!argv[0] || !argv[1]) {
397 				p_err("not enough value arguments for map of progs");
398 				return -1;
399 			}
400 			if (is_prefix(*argv, "id"))
401 				p_info("Warning: updating program array via MAP_ID, make sure this map is kept open\n"
402 				       "         by some process or pinned otherwise update will be lost");
403 
404 			fd = prog_parse_fd(&argc, &argv);
405 			if (fd < 0)
406 				return -1;
407 
408 			*value_fd = value;
409 			**value_fd = fd;
410 		} else {
411 			argv = parse_bytes(argv, "value", value, value_size);
412 			if (!argv)
413 				return -1;
414 
415 			fill_per_cpu_value(info, value);
416 		}
417 
418 		return parse_elem(argv, info, key, NULL, key_size, value_size,
419 				  flags, NULL);
420 	} else if (is_prefix(*argv, "any") || is_prefix(*argv, "noexist") ||
421 		   is_prefix(*argv, "exist")) {
422 		if (!flags) {
423 			p_err("flags specified multiple times: %s", *argv);
424 			return -1;
425 		}
426 
427 		if (is_prefix(*argv, "any"))
428 			*flags = BPF_ANY;
429 		else if (is_prefix(*argv, "noexist"))
430 			*flags = BPF_NOEXIST;
431 		else if (is_prefix(*argv, "exist"))
432 			*flags = BPF_EXIST;
433 
434 		return parse_elem(argv + 1, info, key, value, key_size,
435 				  value_size, NULL, value_fd);
436 	}
437 
438 	p_err("expected key or value, got: %s", *argv);
439 	return -1;
440 }
441 
442 static void show_map_header_json(struct bpf_map_info *info, json_writer_t *wtr)
443 {
444 	const char *map_type_str;
445 
446 	jsonw_uint_field(wtr, "id", info->id);
447 	map_type_str = libbpf_bpf_map_type_str(info->type);
448 	if (map_type_str)
449 		jsonw_string_field(wtr, "type", map_type_str);
450 	else
451 		jsonw_uint_field(wtr, "type", info->type);
452 
453 	if (*info->name)
454 		jsonw_string_field(wtr, "name", info->name);
455 
456 	jsonw_name(wtr, "flags");
457 	jsonw_printf(wtr, "%d", info->map_flags);
458 }
459 
460 static int show_map_close_json(int fd, struct bpf_map_info *info)
461 {
462 	char *memlock, *frozen_str;
463 	int frozen = 0;
464 
465 	memlock = get_fdinfo(fd, "memlock");
466 	frozen_str = get_fdinfo(fd, "frozen");
467 
468 	jsonw_start_object(json_wtr);
469 
470 	show_map_header_json(info, json_wtr);
471 
472 	print_dev_json(info->ifindex, info->netns_dev, info->netns_ino);
473 
474 	jsonw_uint_field(json_wtr, "bytes_key", info->key_size);
475 	jsonw_uint_field(json_wtr, "bytes_value", info->value_size);
476 	jsonw_uint_field(json_wtr, "max_entries", info->max_entries);
477 
478 	if (memlock)
479 		jsonw_int_field(json_wtr, "bytes_memlock", atoll(memlock));
480 	free(memlock);
481 
482 	if (info->type == BPF_MAP_TYPE_PROG_ARRAY) {
483 		char *owner_prog_type = get_fdinfo(fd, "owner_prog_type");
484 		char *owner_jited = get_fdinfo(fd, "owner_jited");
485 
486 		if (owner_prog_type) {
487 			unsigned int prog_type = atoi(owner_prog_type);
488 			const char *prog_type_str;
489 
490 			prog_type_str = libbpf_bpf_prog_type_str(prog_type);
491 			if (prog_type_str)
492 				jsonw_string_field(json_wtr, "owner_prog_type",
493 						   prog_type_str);
494 			else
495 				jsonw_uint_field(json_wtr, "owner_prog_type",
496 						 prog_type);
497 		}
498 		if (owner_jited)
499 			jsonw_bool_field(json_wtr, "owner_jited",
500 					 !!atoi(owner_jited));
501 
502 		free(owner_prog_type);
503 		free(owner_jited);
504 	}
505 	close(fd);
506 
507 	if (frozen_str) {
508 		frozen = atoi(frozen_str);
509 		free(frozen_str);
510 	}
511 	jsonw_int_field(json_wtr, "frozen", frozen);
512 
513 	if (info->btf_id)
514 		jsonw_int_field(json_wtr, "btf_id", info->btf_id);
515 
516 	if (!hashmap__empty(map_table)) {
517 		struct hashmap_entry *entry;
518 
519 		jsonw_name(json_wtr, "pinned");
520 		jsonw_start_array(json_wtr);
521 		hashmap__for_each_key_entry(map_table, entry, info->id)
522 			jsonw_string(json_wtr, entry->pvalue);
523 		jsonw_end_array(json_wtr);
524 	}
525 
526 	emit_obj_refs_json(refs_table, info->id, json_wtr);
527 
528 	jsonw_end_object(json_wtr);
529 
530 	return 0;
531 }
532 
533 static void show_map_header_plain(struct bpf_map_info *info)
534 {
535 	const char *map_type_str;
536 
537 	printf("%u: ", info->id);
538 
539 	map_type_str = libbpf_bpf_map_type_str(info->type);
540 	if (map_type_str)
541 		printf("%s  ", map_type_str);
542 	else
543 		printf("type %u  ", info->type);
544 
545 	if (*info->name)
546 		printf("name %s  ", info->name);
547 
548 	printf("flags 0x%x", info->map_flags);
549 	print_dev_plain(info->ifindex, info->netns_dev, info->netns_ino);
550 	printf("\n");
551 }
552 
553 static int show_map_close_plain(int fd, struct bpf_map_info *info)
554 {
555 	char *memlock, *frozen_str;
556 	int frozen = 0;
557 
558 	memlock = get_fdinfo(fd, "memlock");
559 	frozen_str = get_fdinfo(fd, "frozen");
560 
561 	show_map_header_plain(info);
562 	printf("\tkey %uB  value %uB  max_entries %u",
563 	       info->key_size, info->value_size, info->max_entries);
564 
565 	if (memlock)
566 		printf("  memlock %sB", memlock);
567 	free(memlock);
568 
569 	if (info->type == BPF_MAP_TYPE_PROG_ARRAY) {
570 		char *owner_prog_type = get_fdinfo(fd, "owner_prog_type");
571 		char *owner_jited = get_fdinfo(fd, "owner_jited");
572 
573 		if (owner_prog_type || owner_jited)
574 			printf("\n\t");
575 		if (owner_prog_type) {
576 			unsigned int prog_type = atoi(owner_prog_type);
577 			const char *prog_type_str;
578 
579 			prog_type_str = libbpf_bpf_prog_type_str(prog_type);
580 			if (prog_type_str)
581 				printf("owner_prog_type %s  ", prog_type_str);
582 			else
583 				printf("owner_prog_type %d  ", prog_type);
584 		}
585 		if (owner_jited)
586 			printf("owner%s jited",
587 			       atoi(owner_jited) ? "" : " not");
588 
589 		free(owner_prog_type);
590 		free(owner_jited);
591 	}
592 	close(fd);
593 
594 	if (!hashmap__empty(map_table)) {
595 		struct hashmap_entry *entry;
596 
597 		hashmap__for_each_key_entry(map_table, entry, info->id)
598 			printf("\n\tpinned %s", (char *)entry->pvalue);
599 	}
600 
601 	if (frozen_str) {
602 		frozen = atoi(frozen_str);
603 		free(frozen_str);
604 	}
605 
606 	if (info->btf_id || frozen)
607 		printf("\n\t");
608 
609 	if (info->btf_id)
610 		printf("btf_id %d", info->btf_id);
611 
612 	if (frozen)
613 		printf("%sfrozen", info->btf_id ? "  " : "");
614 
615 	emit_obj_refs_plain(refs_table, info->id, "\n\tpids ");
616 
617 	printf("\n");
618 	return 0;
619 }
620 
621 static int do_show_subset(int argc, char **argv)
622 {
623 	struct bpf_map_info info = {};
624 	__u32 len = sizeof(info);
625 	int *fds = NULL;
626 	int nb_fds, i;
627 	int err = -1;
628 
629 	fds = malloc(sizeof(int));
630 	if (!fds) {
631 		p_err("mem alloc failed");
632 		return -1;
633 	}
634 	nb_fds = map_parse_fds(&argc, &argv, &fds);
635 	if (nb_fds < 1)
636 		goto exit_free;
637 
638 	if (json_output && nb_fds > 1)
639 		jsonw_start_array(json_wtr);	/* root array */
640 	for (i = 0; i < nb_fds; i++) {
641 		err = bpf_map_get_info_by_fd(fds[i], &info, &len);
642 		if (err) {
643 			p_err("can't get map info: %s",
644 			      strerror(errno));
645 			for (; i < nb_fds; i++)
646 				close(fds[i]);
647 			break;
648 		}
649 
650 		if (json_output)
651 			show_map_close_json(fds[i], &info);
652 		else
653 			show_map_close_plain(fds[i], &info);
654 
655 		close(fds[i]);
656 	}
657 	if (json_output && nb_fds > 1)
658 		jsonw_end_array(json_wtr);	/* root array */
659 
660 exit_free:
661 	free(fds);
662 	return err;
663 }
664 
665 static int do_show(int argc, char **argv)
666 {
667 	struct bpf_map_info info = {};
668 	__u32 len = sizeof(info);
669 	__u32 id = 0;
670 	int err;
671 	int fd;
672 
673 	if (show_pinned) {
674 		map_table = hashmap__new(hash_fn_for_key_as_id,
675 					 equal_fn_for_key_as_id, NULL);
676 		if (IS_ERR(map_table)) {
677 			p_err("failed to create hashmap for pinned paths");
678 			return -1;
679 		}
680 		build_pinned_obj_table(map_table, BPF_OBJ_MAP);
681 	}
682 	build_obj_refs_table(&refs_table, BPF_OBJ_MAP);
683 
684 	if (argc == 2)
685 		return do_show_subset(argc, argv);
686 
687 	if (argc)
688 		return BAD_ARG();
689 
690 	if (json_output)
691 		jsonw_start_array(json_wtr);
692 	while (true) {
693 		err = bpf_map_get_next_id(id, &id);
694 		if (err) {
695 			if (errno == ENOENT)
696 				break;
697 			p_err("can't get next map: %s%s", strerror(errno),
698 			      errno == EINVAL ? " -- kernel too old?" : "");
699 			break;
700 		}
701 
702 		fd = bpf_map_get_fd_by_id(id);
703 		if (fd < 0) {
704 			if (errno == ENOENT)
705 				continue;
706 			p_err("can't get map by id (%u): %s",
707 			      id, strerror(errno));
708 			break;
709 		}
710 
711 		err = bpf_map_get_info_by_fd(fd, &info, &len);
712 		if (err) {
713 			p_err("can't get map info: %s", strerror(errno));
714 			close(fd);
715 			break;
716 		}
717 
718 		if (json_output)
719 			show_map_close_json(fd, &info);
720 		else
721 			show_map_close_plain(fd, &info);
722 	}
723 	if (json_output)
724 		jsonw_end_array(json_wtr);
725 
726 	delete_obj_refs_table(refs_table);
727 
728 	if (show_pinned)
729 		delete_pinned_obj_table(map_table);
730 
731 	return errno == ENOENT ? 0 : -1;
732 }
733 
734 static int dump_map_elem(int fd, void *key, void *value,
735 			 struct bpf_map_info *map_info, struct btf *btf,
736 			 json_writer_t *btf_wtr)
737 {
738 	if (bpf_map_lookup_elem(fd, key, value)) {
739 		print_entry_error(map_info, key, errno);
740 		return -1;
741 	}
742 
743 	if (json_output) {
744 		print_entry_json(map_info, key, value, btf);
745 	} else if (btf) {
746 		struct btf_dumper d = {
747 			.btf = btf,
748 			.jw = btf_wtr,
749 			.is_plain_text = true,
750 		};
751 
752 		do_dump_btf(&d, map_info, key, value);
753 	} else {
754 		print_entry_plain(map_info, key, value);
755 	}
756 
757 	return 0;
758 }
759 
760 static int maps_have_btf(int *fds, int nb_fds)
761 {
762 	struct bpf_map_info info = {};
763 	__u32 len = sizeof(info);
764 	int err, i;
765 
766 	for (i = 0; i < nb_fds; i++) {
767 		err = bpf_map_get_info_by_fd(fds[i], &info, &len);
768 		if (err) {
769 			p_err("can't get map info: %s", strerror(errno));
770 			return -1;
771 		}
772 
773 		if (!info.btf_id)
774 			return 0;
775 	}
776 
777 	return 1;
778 }
779 
780 static struct btf *btf_vmlinux;
781 
782 static int get_map_kv_btf(const struct bpf_map_info *info, struct btf **btf)
783 {
784 	int err = 0;
785 
786 	if (info->btf_vmlinux_value_type_id) {
787 		if (!btf_vmlinux) {
788 			btf_vmlinux = libbpf_find_kernel_btf();
789 			if (!btf_vmlinux) {
790 				p_err("failed to get kernel btf");
791 				return -errno;
792 			}
793 		}
794 		*btf = btf_vmlinux;
795 	} else if (info->btf_value_type_id) {
796 		*btf = btf__load_from_kernel_by_id(info->btf_id);
797 		if (!*btf) {
798 			err = -errno;
799 			p_err("failed to get btf");
800 		}
801 	} else {
802 		*btf = NULL;
803 	}
804 
805 	return err;
806 }
807 
808 static void free_map_kv_btf(struct btf *btf)
809 {
810 	if (btf != btf_vmlinux)
811 		btf__free(btf);
812 }
813 
814 static int
815 map_dump(int fd, struct bpf_map_info *info, json_writer_t *wtr,
816 	 bool show_header)
817 {
818 	void *key, *value, *prev_key;
819 	unsigned int num_elems = 0;
820 	struct btf *btf = NULL;
821 	int err;
822 
823 	key = malloc(info->key_size);
824 	value = alloc_value(info);
825 	if (!key || !value) {
826 		p_err("mem alloc failed");
827 		err = -1;
828 		goto exit_free;
829 	}
830 
831 	prev_key = NULL;
832 
833 	if (wtr) {
834 		err = get_map_kv_btf(info, &btf);
835 		if (err) {
836 			goto exit_free;
837 		}
838 
839 		if (show_header) {
840 			jsonw_start_object(wtr);	/* map object */
841 			show_map_header_json(info, wtr);
842 			jsonw_name(wtr, "elements");
843 		}
844 		jsonw_start_array(wtr);		/* elements */
845 	} else if (show_header) {
846 		show_map_header_plain(info);
847 	}
848 
849 	if (info->type == BPF_MAP_TYPE_REUSEPORT_SOCKARRAY &&
850 	    info->value_size != 8) {
851 		const char *map_type_str;
852 
853 		map_type_str = libbpf_bpf_map_type_str(info->type);
854 		p_info("Warning: cannot read values from %s map with value_size != 8",
855 		       map_type_str);
856 	}
857 	while (true) {
858 		err = bpf_map_get_next_key(fd, prev_key, key);
859 		if (err) {
860 			if (errno == ENOENT)
861 				err = 0;
862 			break;
863 		}
864 		if (!dump_map_elem(fd, key, value, info, btf, wtr))
865 			num_elems++;
866 		prev_key = key;
867 	}
868 
869 	if (wtr) {
870 		jsonw_end_array(wtr);	/* elements */
871 		if (show_header)
872 			jsonw_end_object(wtr);	/* map object */
873 	} else {
874 		printf("Found %u element%s\n", num_elems,
875 		       num_elems != 1 ? "s" : "");
876 	}
877 
878 exit_free:
879 	free(key);
880 	free(value);
881 	close(fd);
882 	free_map_kv_btf(btf);
883 
884 	return err;
885 }
886 
887 static int do_dump(int argc, char **argv)
888 {
889 	json_writer_t *wtr = NULL, *btf_wtr = NULL;
890 	struct bpf_map_info info = {};
891 	int nb_fds, i = 0;
892 	__u32 len = sizeof(info);
893 	int *fds = NULL;
894 	int err = -1;
895 
896 	if (argc != 2)
897 		usage();
898 
899 	fds = malloc(sizeof(int));
900 	if (!fds) {
901 		p_err("mem alloc failed");
902 		return -1;
903 	}
904 	nb_fds = map_parse_fds(&argc, &argv, &fds);
905 	if (nb_fds < 1)
906 		goto exit_free;
907 
908 	if (json_output) {
909 		wtr = json_wtr;
910 	} else {
911 		int do_plain_btf;
912 
913 		do_plain_btf = maps_have_btf(fds, nb_fds);
914 		if (do_plain_btf < 0)
915 			goto exit_close;
916 
917 		if (do_plain_btf) {
918 			btf_wtr = get_btf_writer();
919 			wtr = btf_wtr;
920 			if (!btf_wtr)
921 				p_info("failed to create json writer for btf. falling back to plain output");
922 		}
923 	}
924 
925 	if (wtr && nb_fds > 1)
926 		jsonw_start_array(wtr);	/* root array */
927 	for (i = 0; i < nb_fds; i++) {
928 		if (bpf_map_get_info_by_fd(fds[i], &info, &len)) {
929 			p_err("can't get map info: %s", strerror(errno));
930 			break;
931 		}
932 		err = map_dump(fds[i], &info, wtr, nb_fds > 1);
933 		if (!wtr && i != nb_fds - 1)
934 			printf("\n");
935 
936 		if (err)
937 			break;
938 		close(fds[i]);
939 	}
940 	if (wtr && nb_fds > 1)
941 		jsonw_end_array(wtr);	/* root array */
942 
943 	if (btf_wtr)
944 		jsonw_destroy(&btf_wtr);
945 exit_close:
946 	for (; i < nb_fds; i++)
947 		close(fds[i]);
948 exit_free:
949 	free(fds);
950 	btf__free(btf_vmlinux);
951 	return err;
952 }
953 
954 static int alloc_key_value(struct bpf_map_info *info, void **key, void **value)
955 {
956 	*key = NULL;
957 	*value = NULL;
958 
959 	if (info->key_size) {
960 		*key = malloc(info->key_size);
961 		if (!*key) {
962 			p_err("key mem alloc failed");
963 			return -1;
964 		}
965 	}
966 
967 	if (info->value_size) {
968 		*value = alloc_value(info);
969 		if (!*value) {
970 			p_err("value mem alloc failed");
971 			free(*key);
972 			*key = NULL;
973 			return -1;
974 		}
975 	}
976 
977 	return 0;
978 }
979 
980 static int do_update(int argc, char **argv)
981 {
982 	struct bpf_map_info info = {};
983 	__u32 len = sizeof(info);
984 	__u32 *value_fd = NULL;
985 	__u32 flags = BPF_ANY;
986 	void *key, *value;
987 	int fd, err;
988 
989 	if (argc < 2)
990 		usage();
991 
992 	fd = map_parse_fd_and_info(&argc, &argv, &info, &len);
993 	if (fd < 0)
994 		return -1;
995 
996 	err = alloc_key_value(&info, &key, &value);
997 	if (err)
998 		goto exit_free;
999 
1000 	err = parse_elem(argv, &info, key, value, info.key_size,
1001 			 info.value_size, &flags, &value_fd);
1002 	if (err)
1003 		goto exit_free;
1004 
1005 	err = bpf_map_update_elem(fd, key, value, flags);
1006 	if (err) {
1007 		p_err("update failed: %s", strerror(errno));
1008 		goto exit_free;
1009 	}
1010 
1011 exit_free:
1012 	if (value_fd)
1013 		close(*value_fd);
1014 	free(key);
1015 	free(value);
1016 	close(fd);
1017 
1018 	if (!err && json_output)
1019 		jsonw_null(json_wtr);
1020 	return err;
1021 }
1022 
1023 static void print_key_value(struct bpf_map_info *info, void *key,
1024 			    void *value)
1025 {
1026 	json_writer_t *btf_wtr;
1027 	struct btf *btf;
1028 
1029 	if (get_map_kv_btf(info, &btf))
1030 		return;
1031 
1032 	if (json_output) {
1033 		print_entry_json(info, key, value, btf);
1034 	} else if (btf) {
1035 		/* if here json_wtr wouldn't have been initialised,
1036 		 * so let's create separate writer for btf
1037 		 */
1038 		btf_wtr = get_btf_writer();
1039 		if (!btf_wtr) {
1040 			p_info("failed to create json writer for btf. falling back to plain output");
1041 			btf__free(btf);
1042 			btf = NULL;
1043 			print_entry_plain(info, key, value);
1044 		} else {
1045 			struct btf_dumper d = {
1046 				.btf = btf,
1047 				.jw = btf_wtr,
1048 				.is_plain_text = true,
1049 			};
1050 
1051 			do_dump_btf(&d, info, key, value);
1052 			jsonw_destroy(&btf_wtr);
1053 		}
1054 	} else {
1055 		print_entry_plain(info, key, value);
1056 	}
1057 	btf__free(btf);
1058 }
1059 
1060 static int do_lookup(int argc, char **argv)
1061 {
1062 	struct bpf_map_info info = {};
1063 	__u32 len = sizeof(info);
1064 	void *key, *value;
1065 	int err;
1066 	int fd;
1067 
1068 	if (argc < 2)
1069 		usage();
1070 
1071 	fd = map_parse_fd_and_info(&argc, &argv, &info, &len);
1072 	if (fd < 0)
1073 		return -1;
1074 
1075 	err = alloc_key_value(&info, &key, &value);
1076 	if (err)
1077 		goto exit_free;
1078 
1079 	err = parse_elem(argv, &info, key, NULL, info.key_size, 0, NULL, NULL);
1080 	if (err)
1081 		goto exit_free;
1082 
1083 	err = bpf_map_lookup_elem(fd, key, value);
1084 	if (err) {
1085 		if (errno == ENOENT) {
1086 			if (json_output) {
1087 				jsonw_null(json_wtr);
1088 			} else {
1089 				printf("key:\n");
1090 				fprint_hex(stdout, key, info.key_size, " ");
1091 				printf("\n\nNot found\n");
1092 			}
1093 		} else {
1094 			p_err("lookup failed: %s", strerror(errno));
1095 		}
1096 
1097 		goto exit_free;
1098 	}
1099 
1100 	/* here means bpf_map_lookup_elem() succeeded */
1101 	print_key_value(&info, key, value);
1102 
1103 exit_free:
1104 	free(key);
1105 	free(value);
1106 	close(fd);
1107 
1108 	return err;
1109 }
1110 
1111 static int do_getnext(int argc, char **argv)
1112 {
1113 	struct bpf_map_info info = {};
1114 	__u32 len = sizeof(info);
1115 	void *key, *nextkey;
1116 	int err;
1117 	int fd;
1118 
1119 	if (argc < 2)
1120 		usage();
1121 
1122 	fd = map_parse_fd_and_info(&argc, &argv, &info, &len);
1123 	if (fd < 0)
1124 		return -1;
1125 
1126 	key = malloc(info.key_size);
1127 	nextkey = malloc(info.key_size);
1128 	if (!key || !nextkey) {
1129 		p_err("mem alloc failed");
1130 		err = -1;
1131 		goto exit_free;
1132 	}
1133 
1134 	if (argc) {
1135 		err = parse_elem(argv, &info, key, NULL, info.key_size, 0,
1136 				 NULL, NULL);
1137 		if (err)
1138 			goto exit_free;
1139 	} else {
1140 		free(key);
1141 		key = NULL;
1142 	}
1143 
1144 	err = bpf_map_get_next_key(fd, key, nextkey);
1145 	if (err) {
1146 		p_err("can't get next key: %s", strerror(errno));
1147 		goto exit_free;
1148 	}
1149 
1150 	if (json_output) {
1151 		jsonw_start_object(json_wtr);
1152 		if (key) {
1153 			jsonw_name(json_wtr, "key");
1154 			print_hex_data_json(key, info.key_size);
1155 		} else {
1156 			jsonw_null_field(json_wtr, "key");
1157 		}
1158 		jsonw_name(json_wtr, "next_key");
1159 		print_hex_data_json(nextkey, info.key_size);
1160 		jsonw_end_object(json_wtr);
1161 	} else {
1162 		if (key) {
1163 			printf("key:\n");
1164 			fprint_hex(stdout, key, info.key_size, " ");
1165 			printf("\n");
1166 		} else {
1167 			printf("key: None\n");
1168 		}
1169 		printf("next key:\n");
1170 		fprint_hex(stdout, nextkey, info.key_size, " ");
1171 		printf("\n");
1172 	}
1173 
1174 exit_free:
1175 	free(nextkey);
1176 	free(key);
1177 	close(fd);
1178 
1179 	return err;
1180 }
1181 
1182 static int do_delete(int argc, char **argv)
1183 {
1184 	struct bpf_map_info info = {};
1185 	__u32 len = sizeof(info);
1186 	void *key;
1187 	int err;
1188 	int fd;
1189 
1190 	if (argc < 2)
1191 		usage();
1192 
1193 	fd = map_parse_fd_and_info(&argc, &argv, &info, &len);
1194 	if (fd < 0)
1195 		return -1;
1196 
1197 	key = malloc(info.key_size);
1198 	if (!key) {
1199 		p_err("mem alloc failed");
1200 		err = -1;
1201 		goto exit_free;
1202 	}
1203 
1204 	err = parse_elem(argv, &info, key, NULL, info.key_size, 0, NULL, NULL);
1205 	if (err)
1206 		goto exit_free;
1207 
1208 	err = bpf_map_delete_elem(fd, key);
1209 	if (err)
1210 		p_err("delete failed: %s", strerror(errno));
1211 
1212 exit_free:
1213 	free(key);
1214 	close(fd);
1215 
1216 	if (!err && json_output)
1217 		jsonw_null(json_wtr);
1218 	return err;
1219 }
1220 
1221 static int do_pin(int argc, char **argv)
1222 {
1223 	int err;
1224 
1225 	err = do_pin_any(argc, argv, map_parse_fd);
1226 	if (!err && json_output)
1227 		jsonw_null(json_wtr);
1228 	return err;
1229 }
1230 
1231 static int do_create(int argc, char **argv)
1232 {
1233 	LIBBPF_OPTS(bpf_map_create_opts, attr);
1234 	enum bpf_map_type map_type = BPF_MAP_TYPE_UNSPEC;
1235 	__u32 key_size = 0, value_size = 0, max_entries = 0;
1236 	const char *map_name = NULL;
1237 	const char *pinfile;
1238 	int err = -1, fd;
1239 
1240 	if (!REQ_ARGS(7))
1241 		return -1;
1242 	pinfile = GET_ARG();
1243 
1244 	while (argc) {
1245 		if (!REQ_ARGS(2))
1246 			return -1;
1247 
1248 		if (is_prefix(*argv, "type")) {
1249 			NEXT_ARG();
1250 
1251 			if (map_type) {
1252 				p_err("map type already specified");
1253 				goto exit;
1254 			}
1255 
1256 			map_type = map_type_from_str(*argv);
1257 			if ((int)map_type < 0) {
1258 				p_err("unrecognized map type: %s", *argv);
1259 				goto exit;
1260 			}
1261 			NEXT_ARG();
1262 		} else if (is_prefix(*argv, "name")) {
1263 			NEXT_ARG();
1264 			map_name = GET_ARG();
1265 		} else if (is_prefix(*argv, "key")) {
1266 			if (parse_u32_arg(&argc, &argv, &key_size,
1267 					  "key size"))
1268 				goto exit;
1269 		} else if (is_prefix(*argv, "value")) {
1270 			if (parse_u32_arg(&argc, &argv, &value_size,
1271 					  "value size"))
1272 				goto exit;
1273 		} else if (is_prefix(*argv, "entries")) {
1274 			if (parse_u32_arg(&argc, &argv, &max_entries,
1275 					  "max entries"))
1276 				goto exit;
1277 		} else if (is_prefix(*argv, "flags")) {
1278 			if (parse_u32_arg(&argc, &argv, &attr.map_flags,
1279 					  "flags"))
1280 				goto exit;
1281 		} else if (is_prefix(*argv, "dev")) {
1282 			NEXT_ARG();
1283 
1284 			if (attr.map_ifindex) {
1285 				p_err("offload device already specified");
1286 				goto exit;
1287 			}
1288 
1289 			attr.map_ifindex = if_nametoindex(*argv);
1290 			if (!attr.map_ifindex) {
1291 				p_err("unrecognized netdevice '%s': %s",
1292 				      *argv, strerror(errno));
1293 				goto exit;
1294 			}
1295 			NEXT_ARG();
1296 		} else if (is_prefix(*argv, "inner_map")) {
1297 			struct bpf_map_info info = {};
1298 			__u32 len = sizeof(info);
1299 			int inner_map_fd;
1300 
1301 			NEXT_ARG();
1302 			if (!REQ_ARGS(2))
1303 				usage();
1304 			inner_map_fd = map_parse_fd_and_info(&argc, &argv,
1305 							     &info, &len);
1306 			if (inner_map_fd < 0)
1307 				return -1;
1308 			attr.inner_map_fd = inner_map_fd;
1309 		} else {
1310 			p_err("unknown arg %s", *argv);
1311 			goto exit;
1312 		}
1313 	}
1314 
1315 	if (!map_name) {
1316 		p_err("map name not specified");
1317 		goto exit;
1318 	}
1319 
1320 	set_max_rlimit();
1321 
1322 	fd = bpf_map_create(map_type, map_name, key_size, value_size, max_entries, &attr);
1323 	if (fd < 0) {
1324 		p_err("map create failed: %s", strerror(errno));
1325 		goto exit;
1326 	}
1327 
1328 	err = do_pin_fd(fd, pinfile);
1329 	close(fd);
1330 	if (err)
1331 		goto exit;
1332 
1333 	if (json_output)
1334 		jsonw_null(json_wtr);
1335 
1336 exit:
1337 	if (attr.inner_map_fd > 0)
1338 		close(attr.inner_map_fd);
1339 
1340 	return err;
1341 }
1342 
1343 static int do_pop_dequeue(int argc, char **argv)
1344 {
1345 	struct bpf_map_info info = {};
1346 	__u32 len = sizeof(info);
1347 	void *key, *value;
1348 	int err;
1349 	int fd;
1350 
1351 	if (argc < 2)
1352 		usage();
1353 
1354 	fd = map_parse_fd_and_info(&argc, &argv, &info, &len);
1355 	if (fd < 0)
1356 		return -1;
1357 
1358 	err = alloc_key_value(&info, &key, &value);
1359 	if (err)
1360 		goto exit_free;
1361 
1362 	err = bpf_map_lookup_and_delete_elem(fd, key, value);
1363 	if (err) {
1364 		if (errno == ENOENT) {
1365 			if (json_output)
1366 				jsonw_null(json_wtr);
1367 			else
1368 				printf("Error: empty map\n");
1369 		} else {
1370 			p_err("pop failed: %s", strerror(errno));
1371 		}
1372 
1373 		goto exit_free;
1374 	}
1375 
1376 	print_key_value(&info, key, value);
1377 
1378 exit_free:
1379 	free(key);
1380 	free(value);
1381 	close(fd);
1382 
1383 	return err;
1384 }
1385 
1386 static int do_freeze(int argc, char **argv)
1387 {
1388 	int err, fd;
1389 
1390 	if (!REQ_ARGS(2))
1391 		return -1;
1392 
1393 	fd = map_parse_fd(&argc, &argv);
1394 	if (fd < 0)
1395 		return -1;
1396 
1397 	if (argc) {
1398 		close(fd);
1399 		return BAD_ARG();
1400 	}
1401 
1402 	err = bpf_map_freeze(fd);
1403 	close(fd);
1404 	if (err) {
1405 		p_err("failed to freeze map: %s", strerror(errno));
1406 		return err;
1407 	}
1408 
1409 	if (json_output)
1410 		jsonw_null(json_wtr);
1411 
1412 	return 0;
1413 }
1414 
1415 static int do_help(int argc, char **argv)
1416 {
1417 	if (json_output) {
1418 		jsonw_null(json_wtr);
1419 		return 0;
1420 	}
1421 
1422 	fprintf(stderr,
1423 		"Usage: %1$s %2$s { show | list }   [MAP]\n"
1424 		"       %1$s %2$s create     FILE type TYPE key KEY_SIZE value VALUE_SIZE \\\n"
1425 		"                                  entries MAX_ENTRIES name NAME [flags FLAGS] \\\n"
1426 		"                                  [inner_map MAP] [dev NAME]\n"
1427 		"       %1$s %2$s dump       MAP\n"
1428 		"       %1$s %2$s update     MAP [key DATA] [value VALUE] [UPDATE_FLAGS]\n"
1429 		"       %1$s %2$s lookup     MAP [key DATA]\n"
1430 		"       %1$s %2$s getnext    MAP [key DATA]\n"
1431 		"       %1$s %2$s delete     MAP  key DATA\n"
1432 		"       %1$s %2$s pin        MAP  FILE\n"
1433 		"       %1$s %2$s event_pipe MAP [cpu N index M]\n"
1434 		"       %1$s %2$s peek       MAP\n"
1435 		"       %1$s %2$s push       MAP value VALUE\n"
1436 		"       %1$s %2$s pop        MAP\n"
1437 		"       %1$s %2$s enqueue    MAP value VALUE\n"
1438 		"       %1$s %2$s dequeue    MAP\n"
1439 		"       %1$s %2$s freeze     MAP\n"
1440 		"       %1$s %2$s help\n"
1441 		"\n"
1442 		"       " HELP_SPEC_MAP "\n"
1443 		"       DATA := { [hex] BYTES }\n"
1444 		"       " HELP_SPEC_PROGRAM "\n"
1445 		"       VALUE := { DATA | MAP | PROG }\n"
1446 		"       UPDATE_FLAGS := { any | exist | noexist }\n"
1447 		"       TYPE := { hash | array | prog_array | perf_event_array | percpu_hash |\n"
1448 		"                 percpu_array | stack_trace | cgroup_array | lru_hash |\n"
1449 		"                 lru_percpu_hash | lpm_trie | array_of_maps | hash_of_maps |\n"
1450 		"                 devmap | devmap_hash | sockmap | cpumap | xskmap | sockhash |\n"
1451 		"                 cgroup_storage | reuseport_sockarray | percpu_cgroup_storage |\n"
1452 		"                 queue | stack | sk_storage | struct_ops | ringbuf | inode_storage |\n"
1453 		"                 task_storage | bloom_filter | user_ringbuf | cgrp_storage }\n"
1454 		"       " HELP_SPEC_OPTIONS " |\n"
1455 		"                    {-f|--bpffs} | {-n|--nomount} }\n"
1456 		"",
1457 		bin_name, argv[-2]);
1458 
1459 	return 0;
1460 }
1461 
1462 static const struct cmd cmds[] = {
1463 	{ "show",	do_show },
1464 	{ "list",	do_show },
1465 	{ "help",	do_help },
1466 	{ "dump",	do_dump },
1467 	{ "update",	do_update },
1468 	{ "lookup",	do_lookup },
1469 	{ "getnext",	do_getnext },
1470 	{ "delete",	do_delete },
1471 	{ "pin",	do_pin },
1472 	{ "event_pipe",	do_event_pipe },
1473 	{ "create",	do_create },
1474 	{ "peek",	do_lookup },
1475 	{ "push",	do_update },
1476 	{ "enqueue",	do_update },
1477 	{ "pop",	do_pop_dequeue },
1478 	{ "dequeue",	do_pop_dequeue },
1479 	{ "freeze",	do_freeze },
1480 	{ 0 }
1481 };
1482 
1483 int do_map(int argc, char **argv)
1484 {
1485 	return cmd_select(cmds, argc, argv, do_help);
1486 }
1487