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, 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 }