tools/bpf/bpftool/map.c

   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,
 522                                             u32_as_hash_field(info->id))
 523                         jsonw_string(json_wtr, entry->value);
 524                 jsonw_end_array(json_wtr);
 525         }
 526
 527         emit_obj_refs_json(refs_table, info->id, json_wtr);
 528
 529         jsonw_end_object(json_wtr);
 530
 531         return 0;
 532 }
 533
 534 static void show_map_header_plain(struct bpf_map_info *info)
 535 {
 536         const char *map_type_str;
 537
 538         printf("%u: ", info->id);
 539
 540         map_type_str = libbpf_bpf_map_type_str(info->type);
 541         if (map_type_str)
 542                 printf("%s  ", map_type_str);
 543         else
 544                 printf("type %u  ", info->type);
 545
 546         if (*info->name)
 547                 printf("name %s  ", info->name);
 548
 549         printf("flags 0x%x", info->map_flags);
 550         print_dev_plain(info->ifindex, info->netns_dev, info->netns_ino);
 551         printf("\n");
 552 }
 553
 554 static int show_map_close_plain(int fd, struct bpf_map_info *info)
 555 {
 556         char *memlock, *frozen_str;
 557         int frozen = 0;
 558
 559         memlock = get_fdinfo(fd, "memlock");
 560         frozen_str = get_fdinfo(fd, "frozen");
 561
 562         show_map_header_plain(info);
 563         printf("\tkey %uB  value %uB  max_entries %u",
 564                info->key_size, info->value_size, info->max_entries);
 565
 566         if (memlock)
 567                 printf("  memlock %sB", memlock);
 568         free(memlock);
 569
 570         if (info->type == BPF_MAP_TYPE_PROG_ARRAY) {
 571                 char *owner_prog_type = get_fdinfo(fd, "owner_prog_type");
 572                 char *owner_jited = get_fdinfo(fd, "owner_jited");
 573
 574                 if (owner_prog_type || owner_jited)
 575                         printf("\n\t");
 576                 if (owner_prog_type) {
 577                         unsigned int prog_type = atoi(owner_prog_type);
 578                         const char *prog_type_str;
 579
 580                         prog_type_str = libbpf_bpf_prog_type_str(prog_type);
 581                         if (prog_type_str)
 582                                 printf("owner_prog_type %s  ", prog_type_str);
 583                         else
 584                                 printf("owner_prog_type %d  ", prog_type);
 585                 }
 586                 if (owner_jited)
 587                         printf("owner%s jited",
 588                                atoi(owner_jited) ? "" : " not");
 589
 590                 free(owner_prog_type);
 591                 free(owner_jited);
 592         }
 593         close(fd);
 594
 595         if (!hashmap__empty(map_table)) {
 596                 struct hashmap_entry *entry;
 597
 598                 hashmap__for_each_key_entry(map_table, entry,
 599                                             u32_as_hash_field(info->id))
 600                         printf("\n\tpinned %s", (char *)entry->value);
 601         }
 602
 603         if (frozen_str) {
 604                 frozen = atoi(frozen_str);
 605                 free(frozen_str);
 606         }
 607
 608         if (info->btf_id || frozen)
 609                 printf("\n\t");
 610
 611         if (info->btf_id)
 612                 printf("btf_id %d", info->btf_id);
 613
 614         if (frozen)
 615                 printf("%sfrozen", info->btf_id ? "  " : "");
 616
 617         emit_obj_refs_plain(refs_table, info->id, "\n\tpids ");
 618
 619         printf("\n");
 620         return 0;
 621 }
 622
 623 static int do_show_subset(int argc, char **argv)
 624 {
 625         struct bpf_map_info info = {};
 626         __u32 len = sizeof(info);
 627         int *fds = NULL;
 628         int nb_fds, i;
 629         int err = -1;
 630
 631         fds = malloc(sizeof(int));
 632         if (!fds) {
 633                 p_err("mem alloc failed");
 634                 return -1;
 635         }
 636         nb_fds = map_parse_fds(&argc, &argv, &fds);
 637         if (nb_fds < 1)
 638                 goto exit_free;
 639
 640         if (json_output && nb_fds > 1)
 641                 jsonw_start_array(json_wtr);    /* root array */
 642         for (i = 0; i < nb_fds; i++) {
 643                 err = bpf_obj_get_info_by_fd(fds[i], &info, &len);
 644                 if (err) {
 645                         p_err("can't get map info: %s",
 646                               strerror(errno));
 647                         for (; i < nb_fds; i++)
 648                                 close(fds[i]);
 649                         break;
 650                 }
 651
 652                 if (json_output)
 653                         show_map_close_json(fds[i], &info);
 654                 else
 655                         show_map_close_plain(fds[i], &info);
 656
 657                 close(fds[i]);
 658         }
 659         if (json_output && nb_fds > 1)
 660                 jsonw_end_array(json_wtr);      /* root array */
 661
 662 exit_free:
 663         free(fds);
 664         return err;
 665 }
 666
 667 static int do_show(int argc, char **argv)
 668 {
 669         struct bpf_map_info info = {};
 670         __u32 len = sizeof(info);
 671         __u32 id = 0;
 672         int err;
 673         int fd;
 674
 675         if (show_pinned) {
 676                 map_table = hashmap__new(hash_fn_for_key_as_id,
 677                                          equal_fn_for_key_as_id, NULL);
 678                 if (IS_ERR(map_table)) {
 679                         p_err("failed to create hashmap for pinned paths");
 680                         return -1;
 681                 }
 682                 build_pinned_obj_table(map_table, BPF_OBJ_MAP);
 683         }
 684         build_obj_refs_table(&refs_table, BPF_OBJ_MAP);
 685
 686         if (argc == 2)
 687                 return do_show_subset(argc, argv);
 688
 689         if (argc)
 690                 return BAD_ARG();
 691
 692         if (json_output)
 693                 jsonw_start_array(json_wtr);
 694         while (true) {
 695                 err = bpf_map_get_next_id(id, &id);
 696                 if (err) {
 697                         if (errno == ENOENT)
 698                                 break;
 699                         p_err("can't get next map: %s%s", strerror(errno),
 700                               errno == EINVAL ? " -- kernel too old?" : "");
 701                         break;
 702                 }
 703
 704                 fd = bpf_map_get_fd_by_id(id);
 705                 if (fd < 0) {
 706                         if (errno == ENOENT)
 707                                 continue;
 708                         p_err("can't get map by id (%u): %s",
 709                               id, strerror(errno));
 710                         break;
 711                 }
 712
 713                 err = bpf_obj_get_info_by_fd(fd, &info, &len);
 714                 if (err) {
 715                         p_err("can't get map info: %s", strerror(errno));
 716                         close(fd);
 717                         break;
 718                 }
 719
 720                 if (json_output)
 721                         show_map_close_json(fd, &info);
 722                 else
 723                         show_map_close_plain(fd, &info);
 724         }
 725         if (json_output)
 726                 jsonw_end_array(json_wtr);
 727
 728         delete_obj_refs_table(refs_table);
 729
 730         if (show_pinned)
 731                 delete_pinned_obj_table(map_table);
 732
 733         return errno == ENOENT ? 0 : -1;
 734 }
 735
 736 static int dump_map_elem(int fd, void *key, void *value,
 737                          struct bpf_map_info *map_info, struct btf *btf,
 738                          json_writer_t *btf_wtr)
 739 {
 740         if (bpf_map_lookup_elem(fd, key, value)) {
 741                 print_entry_error(map_info, key, errno);
 742                 return -1;
 743         }
 744
 745         if (json_output) {
 746                 print_entry_json(map_info, key, value, btf);
 747         } else if (btf) {
 748                 struct btf_dumper d = {
 749                         .btf = btf,
 750                         .jw = btf_wtr,
 751                         .is_plain_text = true,
 752                 };
 753
 754                 do_dump_btf(&d, map_info, key, value);
 755         } else {
 756                 print_entry_plain(map_info, key, value);
 757         }
 758
 759         return 0;
 760 }
 761
 762 static int maps_have_btf(int *fds, int nb_fds)
 763 {
 764         struct bpf_map_info info = {};
 765         __u32 len = sizeof(info);
 766         int err, i;
 767
 768         for (i = 0; i < nb_fds; i++) {
 769                 err = bpf_obj_get_info_by_fd(fds[i], &info, &len);
 770                 if (err) {
 771                         p_err("can't get map info: %s", strerror(errno));
 772                         return -1;
 773                 }
 774
 775                 if (!info.btf_id)
 776                         return 0;
 777         }
 778
 779         return 1;
 780 }
 781
 782 static struct btf *btf_vmlinux;
 783
 784 static int get_map_kv_btf(const struct bpf_map_info *info, struct btf **btf)
 785 {
 786         int err = 0;
 787
 788         if (info->btf_vmlinux_value_type_id) {
 789                 if (!btf_vmlinux) {
 790                         btf_vmlinux = libbpf_find_kernel_btf();
 791                         err = libbpf_get_error(btf_vmlinux);
 792                         if (err) {
 793                                 p_err("failed to get kernel btf");
 794                                 return err;
 795                         }
 796                 }
 797                 *btf = btf_vmlinux;
 798         } else if (info->btf_value_type_id) {
 799                 *btf = btf__load_from_kernel_by_id(info->btf_id);
 800                 err = libbpf_get_error(*btf);
 801                 if (err)
 802                         p_err("failed to get btf");
 803         } else {
 804                 *btf = NULL;
 805         }
 806
 807         return err;
 808 }
 809
 810 static void free_map_kv_btf(struct btf *btf)
 811 {
 812         if (!libbpf_get_error(btf) && btf != btf_vmlinux)
 813                 btf__free(btf);
 814 }
 815
 816 static void free_btf_vmlinux(void)
 817 {
 818         if (!libbpf_get_error(btf_vmlinux))
 819                 btf__free(btf_vmlinux);
 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_obj_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         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                         NEXT_ARG();
1291
1292                         if (attr.map_ifindex) {
1293                                 p_err("offload device already specified");
1294                                 goto exit;
1295                         }
1296
1297                         attr.map_ifindex = if_nametoindex(*argv);
1298                         if (!attr.map_ifindex) {
1299                                 p_err("unrecognized netdevice '%s': %s",
1300                                       *argv, strerror(errno));
1301                                 goto exit;
1302                         }
1303                         NEXT_ARG();
1304                 } else if (is_prefix(*argv, "inner_map")) {
1305                         struct bpf_map_info info = {};
1306                         __u32 len = sizeof(info);
1307                         int inner_map_fd;
1308
1309                         NEXT_ARG();
1310                         if (!REQ_ARGS(2))
1311                                 usage();
1312                         inner_map_fd = map_parse_fd_and_info(&argc, &argv,
1313                                                              &info, &len);
1314                         if (inner_map_fd < 0)
1315                                 return -1;
1316                         attr.inner_map_fd = inner_map_fd;
1317                 } else {
1318                         p_err("unknown arg %s", *argv);
1319                         goto exit;
1320                 }
1321         }
1322
1323         if (!map_name) {
1324                 p_err("map name not specified");
1325                 goto exit;
1326         }
1327
1328         set_max_rlimit();
1329
1330         fd = bpf_map_create(map_type, map_name, key_size, value_size, max_entries, &attr);
1331         if (fd < 0) {
1332                 p_err("map create failed: %s", strerror(errno));
1333                 goto exit;
1334         }
1335
1336         err = do_pin_fd(fd, pinfile);
1337         close(fd);
1338         if (err)
1339                 goto exit;
1340
1341         if (json_output)
1342                 jsonw_null(json_wtr);
1343
1344 exit:
1345         if (attr.inner_map_fd > 0)
1346                 close(attr.inner_map_fd);
1347
1348         return err;
1349 }
1350
1351 static int do_pop_dequeue(int argc, char **argv)
1352 {
1353         struct bpf_map_info info = {};
1354         __u32 len = sizeof(info);
1355         void *key, *value;
1356         int err;
1357         int fd;
1358
1359         if (argc < 2)
1360                 usage();
1361
1362         fd = map_parse_fd_and_info(&argc, &argv, &info, &len);
1363         if (fd < 0)
1364                 return -1;
1365
1366         err = alloc_key_value(&info, &key, &value);
1367         if (err)
1368                 goto exit_free;
1369
1370         err = bpf_map_lookup_and_delete_elem(fd, key, value);
1371         if (err) {
1372                 if (errno == ENOENT) {
1373                         if (json_output)
1374                                 jsonw_null(json_wtr);
1375                         else
1376                                 printf("Error: empty map\n");
1377                 } else {
1378                         p_err("pop failed: %s", strerror(errno));
1379                 }
1380
1381                 goto exit_free;
1382         }
1383
1384         print_key_value(&info, key, value);
1385
1386 exit_free:
1387         free(key);
1388         free(value);
1389         close(fd);
1390
1391         return err;
1392 }
1393
1394 static int do_freeze(int argc, char **argv)
1395 {
1396         int err, fd;
1397
1398         if (!REQ_ARGS(2))
1399                 return -1;
1400
1401         fd = map_parse_fd(&argc, &argv);
1402         if (fd < 0)
1403                 return -1;
1404
1405         if (argc) {
1406                 close(fd);
1407                 return BAD_ARG();
1408         }
1409
1410         err = bpf_map_freeze(fd);
1411         close(fd);
1412         if (err) {
1413                 p_err("failed to freeze map: %s", strerror(errno));
1414                 return err;
1415         }
1416
1417         if (json_output)
1418                 jsonw_null(json_wtr);
1419
1420         return 0;
1421 }
1422
1423 static int do_help(int argc, char **argv)
1424 {
1425         if (json_output) {
1426                 jsonw_null(json_wtr);
1427                 return 0;
1428         }
1429
1430         fprintf(stderr,
1431                 "Usage: %1$s %2$s { show | list }   [MAP]\n"
1432                 "       %1$s %2$s create     FILE type TYPE key KEY_SIZE value VALUE_SIZE \\\n"
1433                 "                                  entries MAX_ENTRIES name NAME [flags FLAGS] \\\n"
1434                 "                                  [inner_map MAP] [dev NAME]\n"
1435                 "       %1$s %2$s dump       MAP\n"
1436                 "       %1$s %2$s update     MAP [key DATA] [value VALUE] [UPDATE_FLAGS]\n"
1437                 "       %1$s %2$s lookup     MAP [key DATA]\n"
1438                 "       %1$s %2$s getnext    MAP [key DATA]\n"
1439                 "       %1$s %2$s delete     MAP  key DATA\n"
1440                 "       %1$s %2$s pin        MAP  FILE\n"
1441                 "       %1$s %2$s event_pipe MAP [cpu N index M]\n"
1442                 "       %1$s %2$s peek       MAP\n"
1443                 "       %1$s %2$s push       MAP value VALUE\n"
1444                 "       %1$s %2$s pop        MAP\n"
1445                 "       %1$s %2$s enqueue    MAP value VALUE\n"
1446                 "       %1$s %2$s dequeue    MAP\n"
1447                 "       %1$s %2$s freeze     MAP\n"
1448                 "       %1$s %2$s help\n"
1449                 "\n"
1450                 "       " HELP_SPEC_MAP "\n"
1451                 "       DATA := { [hex] BYTES }\n"
1452                 "       " HELP_SPEC_PROGRAM "\n"
1453                 "       VALUE := { DATA | MAP | PROG }\n"
1454                 "       UPDATE_FLAGS := { any | exist | noexist }\n"
1455                 "       TYPE := { hash | array | prog_array | perf_event_array | percpu_hash |\n"
1456                 "                 percpu_array | stack_trace | cgroup_array | lru_hash |\n"
1457                 "                 lru_percpu_hash | lpm_trie | array_of_maps | hash_of_maps |\n"
1458                 "                 devmap | devmap_hash | sockmap | cpumap | xskmap | sockhash |\n"
1459                 "                 cgroup_storage | reuseport_sockarray | percpu_cgroup_storage |\n"
1460                 "                 queue | stack | sk_storage | struct_ops | ringbuf | inode_storage |\n"
1461                 "                 task_storage | bloom_filter | user_ringbuf }\n"
1462                 "       " HELP_SPEC_OPTIONS " |\n"
1463                 "                    {-f|--bpffs} | {-n|--nomount} }\n"
1464                 "",
1465                 bin_name, argv[-2]);
1466
1467         return 0;
1468 }
1469
1470 static const struct cmd cmds[] = {
1471         { "show",       do_show },
1472         { "list",       do_show },
1473         { "help",       do_help },
1474         { "dump",       do_dump },
1475         { "update",     do_update },
1476         { "lookup",     do_lookup },
1477         { "getnext",    do_getnext },
1478         { "delete",     do_delete },
1479         { "pin",        do_pin },
1480         { "event_pipe", do_event_pipe },
1481         { "create",     do_create },
1482         { "peek",       do_lookup },
1483         { "push",       do_update },
1484         { "enqueue",    do_update },
1485         { "pop",        do_pop_dequeue },
1486         { "dequeue",    do_pop_dequeue },
1487         { "freeze",     do_freeze },
1488         { 0 }
1489 };
1490
1491 int do_map(int argc, char **argv)
1492 {
1493         return cmd_select(cmds, argc, argv, do_help);
1494 }