tools/bpf/bpftool/map.c

   1 /*
   2  * Copyright (C) 2017-2018 Netronome Systems, Inc.
   3  *
   4  * This software is dual licensed under the GNU General License Version 2,
   5  * June 1991 as shown in the file COPYING in the top-level directory of this
   6  * source tree or the BSD 2-Clause License provided below.  You have the
   7  * option to license this software under the complete terms of either license.
   8  *
   9  * The BSD 2-Clause License:
  10  *
  11  *     Redistribution and use in source and binary forms, with or
  12  *     without modification, are permitted provided that the following
  13  *     conditions are met:
  14  *
  15  *      1. Redistributions of source code must retain the above
  16  *         copyright notice, this list of conditions and the following
  17  *         disclaimer.
  18  *
  19  *      2. Redistributions in binary form must reproduce the above
  20  *         copyright notice, this list of conditions and the following
  21  *         disclaimer in the documentation and/or other materials
  22  *         provided with the distribution.
  23  *
  24  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  25  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  26  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  27  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
  28  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
  29  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  30  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  31  * SOFTWARE.
  32  */
  33
  34 #include <assert.h>
  35 #include <errno.h>
  36 #include <fcntl.h>
  37 #include <linux/err.h>
  38 #include <linux/kernel.h>
  39 #include <stdbool.h>
  40 #include <stdio.h>
  41 #include <stdlib.h>
  42 #include <string.h>
  43 #include <unistd.h>
  44 #include <sys/types.h>
  45 #include <sys/stat.h>
  46
  47 #include <bpf.h>
  48
  49 #include "btf.h"
  50 #include "json_writer.h"
  51 #include "main.h"
  52
  53 static const char * const map_type_name[] = {
  54         [BPF_MAP_TYPE_UNSPEC]           = "unspec",
  55         [BPF_MAP_TYPE_HASH]             = "hash",
  56         [BPF_MAP_TYPE_ARRAY]            = "array",
  57         [BPF_MAP_TYPE_PROG_ARRAY]       = "prog_array",
  58         [BPF_MAP_TYPE_PERF_EVENT_ARRAY] = "perf_event_array",
  59         [BPF_MAP_TYPE_PERCPU_HASH]      = "percpu_hash",
  60         [BPF_MAP_TYPE_PERCPU_ARRAY]     = "percpu_array",
  61         [BPF_MAP_TYPE_STACK_TRACE]      = "stack_trace",
  62         [BPF_MAP_TYPE_CGROUP_ARRAY]     = "cgroup_array",
  63         [BPF_MAP_TYPE_LRU_HASH]         = "lru_hash",
  64         [BPF_MAP_TYPE_LRU_PERCPU_HASH]  = "lru_percpu_hash",
  65         [BPF_MAP_TYPE_LPM_TRIE]         = "lpm_trie",
  66         [BPF_MAP_TYPE_ARRAY_OF_MAPS]    = "array_of_maps",
  67         [BPF_MAP_TYPE_HASH_OF_MAPS]     = "hash_of_maps",
  68         [BPF_MAP_TYPE_DEVMAP]           = "devmap",
  69         [BPF_MAP_TYPE_SOCKMAP]          = "sockmap",
  70         [BPF_MAP_TYPE_CPUMAP]           = "cpumap",
  71         [BPF_MAP_TYPE_XSKMAP]           = "xskmap",
  72         [BPF_MAP_TYPE_SOCKHASH]         = "sockhash",
  73         [BPF_MAP_TYPE_CGROUP_STORAGE]   = "cgroup_storage",
  74 };
  75
  76 static bool map_is_per_cpu(__u32 type)
  77 {
  78         return type == BPF_MAP_TYPE_PERCPU_HASH ||
  79                type == BPF_MAP_TYPE_PERCPU_ARRAY ||
  80                type == BPF_MAP_TYPE_LRU_PERCPU_HASH;
  81 }
  82
  83 static bool map_is_map_of_maps(__u32 type)
  84 {
  85         return type == BPF_MAP_TYPE_ARRAY_OF_MAPS ||
  86                type == BPF_MAP_TYPE_HASH_OF_MAPS;
  87 }
  88
  89 static bool map_is_map_of_progs(__u32 type)
  90 {
  91         return type == BPF_MAP_TYPE_PROG_ARRAY;
  92 }
  93
  94 static void *alloc_value(struct bpf_map_info *info)
  95 {
  96         if (map_is_per_cpu(info->type))
  97                 return malloc(round_up(info->value_size, 8) *
  98                               get_possible_cpus());
  99         else
 100                 return malloc(info->value_size);
 101 }
 102
 103 int map_parse_fd(int *argc, char ***argv)
 104 {
 105         int fd;
 106
 107         if (is_prefix(**argv, "id")) {
 108                 unsigned int id;
 109                 char *endptr;
 110
 111                 NEXT_ARGP();
 112
 113                 id = strtoul(**argv, &endptr, 0);
 114                 if (*endptr) {
 115                         p_err("can't parse %s as ID", **argv);
 116                         return -1;
 117                 }
 118                 NEXT_ARGP();
 119
 120                 fd = bpf_map_get_fd_by_id(id);
 121                 if (fd < 0)
 122                         p_err("get map by id (%u): %s", id, strerror(errno));
 123                 return fd;
 124         } else if (is_prefix(**argv, "pinned")) {
 125                 char *path;
 126
 127                 NEXT_ARGP();
 128
 129                 path = **argv;
 130                 NEXT_ARGP();
 131
 132                 return open_obj_pinned_any(path, BPF_OBJ_MAP);
 133         }
 134
 135         p_err("expected 'id' or 'pinned', got: '%s'?", **argv);
 136         return -1;
 137 }
 138
 139 int map_parse_fd_and_info(int *argc, char ***argv, void *info, __u32 *info_len)
 140 {
 141         int err;
 142         int fd;
 143
 144         fd = map_parse_fd(argc, argv);
 145         if (fd < 0)
 146                 return -1;
 147
 148         err = bpf_obj_get_info_by_fd(fd, info, info_len);
 149         if (err) {
 150                 p_err("can't get map info: %s", strerror(errno));
 151                 close(fd);
 152                 return err;
 153         }
 154
 155         return fd;
 156 }
 157
 158 static int do_dump_btf(const struct btf_dumper *d,
 159                        struct bpf_map_info *map_info, void *key,
 160                        void *value)
 161 {
 162         int ret;
 163
 164         /* start of key-value pair */
 165         jsonw_start_object(d->jw);
 166
 167         jsonw_name(d->jw, "key");
 168
 169         ret = btf_dumper_type(d, map_info->btf_key_type_id, key);
 170         if (ret)
 171                 goto err_end_obj;
 172
 173         jsonw_name(d->jw, "value");
 174
 175         ret = btf_dumper_type(d, map_info->btf_value_type_id, value);
 176
 177 err_end_obj:
 178         /* end of key-value pair */
 179         jsonw_end_object(d->jw);
 180
 181         return ret;
 182 }
 183
 184 static int get_btf(struct bpf_map_info *map_info, struct btf **btf)
 185 {
 186         struct bpf_btf_info btf_info = { 0 };
 187         __u32 len = sizeof(btf_info);
 188         __u32 last_size;
 189         int btf_fd;
 190         void *ptr;
 191         int err;
 192
 193         err = 0;
 194         *btf = NULL;
 195         btf_fd = bpf_btf_get_fd_by_id(map_info->btf_id);
 196         if (btf_fd < 0)
 197                 return 0;
 198
 199         /* we won't know btf_size until we call bpf_obj_get_info_by_fd(). so
 200          * let's start with a sane default - 4KiB here - and resize it only if
 201          * bpf_obj_get_info_by_fd() needs a bigger buffer.
 202          */
 203         btf_info.btf_size = 4096;
 204         last_size = btf_info.btf_size;
 205         ptr = malloc(last_size);
 206         if (!ptr) {
 207                 err = -ENOMEM;
 208                 goto exit_free;
 209         }
 210
 211         bzero(ptr, last_size);
 212         btf_info.btf = ptr_to_u64(ptr);
 213         err = bpf_obj_get_info_by_fd(btf_fd, &btf_info, &len);
 214
 215         if (!err && btf_info.btf_size > last_size) {
 216                 void *temp_ptr;
 217
 218                 last_size = btf_info.btf_size;
 219                 temp_ptr = realloc(ptr, last_size);
 220                 if (!temp_ptr) {
 221                         err = -ENOMEM;
 222                         goto exit_free;
 223                 }
 224                 ptr = temp_ptr;
 225                 bzero(ptr, last_size);
 226                 btf_info.btf = ptr_to_u64(ptr);
 227                 err = bpf_obj_get_info_by_fd(btf_fd, &btf_info, &len);
 228         }
 229
 230         if (err || btf_info.btf_size > last_size) {
 231                 err = errno;
 232                 goto exit_free;
 233         }
 234
 235         *btf = btf__new((__u8 *)btf_info.btf, btf_info.btf_size, NULL);
 236         if (IS_ERR(*btf)) {
 237                 err = PTR_ERR(*btf);
 238                 *btf = NULL;
 239         }
 240
 241 exit_free:
 242         close(btf_fd);
 243         free(ptr);
 244
 245         return err;
 246 }
 247
 248 static json_writer_t *get_btf_writer(void)
 249 {
 250         json_writer_t *jw = jsonw_new(stdout);
 251
 252         if (!jw)
 253                 return NULL;
 254         jsonw_pretty(jw, true);
 255
 256         return jw;
 257 }
 258
 259 static void print_entry_json(struct bpf_map_info *info, unsigned char *key,
 260                              unsigned char *value, struct btf *btf)
 261 {
 262         jsonw_start_object(json_wtr);
 263
 264         if (!map_is_per_cpu(info->type)) {
 265                 jsonw_name(json_wtr, "key");
 266                 print_hex_data_json(key, info->key_size);
 267                 jsonw_name(json_wtr, "value");
 268                 print_hex_data_json(value, info->value_size);
 269                 if (btf) {
 270                         struct btf_dumper d = {
 271                                 .btf = btf,
 272                                 .jw = json_wtr,
 273                                 .is_plain_text = false,
 274                         };
 275
 276                         jsonw_name(json_wtr, "formatted");
 277                         do_dump_btf(&d, info, key, value);
 278                 }
 279         } else {
 280                 unsigned int i, n, step;
 281
 282                 n = get_possible_cpus();
 283                 step = round_up(info->value_size, 8);
 284
 285                 jsonw_name(json_wtr, "key");
 286                 print_hex_data_json(key, info->key_size);
 287
 288                 jsonw_name(json_wtr, "values");
 289                 jsonw_start_array(json_wtr);
 290                 for (i = 0; i < n; i++) {
 291                         jsonw_start_object(json_wtr);
 292
 293                         jsonw_int_field(json_wtr, "cpu", i);
 294
 295                         jsonw_name(json_wtr, "value");
 296                         print_hex_data_json(value + i * step,
 297                                             info->value_size);
 298
 299                         jsonw_end_object(json_wtr);
 300                 }
 301                 jsonw_end_array(json_wtr);
 302         }
 303
 304         jsonw_end_object(json_wtr);
 305 }
 306
 307 static void print_entry_plain(struct bpf_map_info *info, unsigned char *key,
 308                               unsigned char *value)
 309 {
 310         if (!map_is_per_cpu(info->type)) {
 311                 bool single_line, break_names;
 312
 313                 break_names = info->key_size > 16 || info->value_size > 16;
 314                 single_line = info->key_size + info->value_size <= 24 &&
 315                         !break_names;
 316
 317                 printf("key:%c", break_names ? '\n' : ' ');
 318                 fprint_hex(stdout, key, info->key_size, " ");
 319
 320                 printf(single_line ? "  " : "\n");
 321
 322                 printf("value:%c", break_names ? '\n' : ' ');
 323                 fprint_hex(stdout, value, info->value_size, " ");
 324
 325                 printf("\n");
 326         } else {
 327                 unsigned int i, n, step;
 328
 329                 n = get_possible_cpus();
 330                 step = round_up(info->value_size, 8);
 331
 332                 printf("key:\n");
 333                 fprint_hex(stdout, key, info->key_size, " ");
 334                 printf("\n");
 335                 for (i = 0; i < n; i++) {
 336                         printf("value (CPU %02d):%c",
 337                                i, info->value_size > 16 ? '\n' : ' ');
 338                         fprint_hex(stdout, value + i * step,
 339                                    info->value_size, " ");
 340                         printf("\n");
 341                 }
 342         }
 343 }
 344
 345 static char **parse_bytes(char **argv, const char *name, unsigned char *val,
 346                           unsigned int n)
 347 {
 348         unsigned int i = 0, base = 0;
 349         char *endptr;
 350
 351         if (is_prefix(*argv, "hex")) {
 352                 base = 16;
 353                 argv++;
 354         }
 355
 356         while (i < n && argv[i]) {
 357                 val[i] = strtoul(argv[i], &endptr, base);
 358                 if (*endptr) {
 359                         p_err("error parsing byte: %s", argv[i]);
 360                         return NULL;
 361                 }
 362                 i++;
 363         }
 364
 365         if (i != n) {
 366                 p_err("%s expected %d bytes got %d", name, n, i);
 367                 return NULL;
 368         }
 369
 370         return argv + i;
 371 }
 372
 373 /* on per cpu maps we must copy the provided value on all value instances */
 374 static void fill_per_cpu_value(struct bpf_map_info *info, void *value)
 375 {
 376         unsigned int i, n, step;
 377
 378         if (!map_is_per_cpu(info->type))
 379                 return;
 380
 381         n = get_possible_cpus();
 382         step = round_up(info->value_size, 8);
 383         for (i = 1; i < n; i++)
 384                 memcpy(value + i * step, value, info->value_size);
 385 }
 386
 387 static int parse_elem(char **argv, struct bpf_map_info *info,
 388                       void *key, void *value, __u32 key_size, __u32 value_size,
 389                       __u32 *flags, __u32 **value_fd)
 390 {
 391         if (!*argv) {
 392                 if (!key && !value)
 393                         return 0;
 394                 p_err("did not find %s", key ? "key" : "value");
 395                 return -1;
 396         }
 397
 398         if (is_prefix(*argv, "key")) {
 399                 if (!key) {
 400                         if (key_size)
 401                                 p_err("duplicate key");
 402                         else
 403                                 p_err("unnecessary key");
 404                         return -1;
 405                 }
 406
 407                 argv = parse_bytes(argv + 1, "key", key, key_size);
 408                 if (!argv)
 409                         return -1;
 410
 411                 return parse_elem(argv, info, NULL, value, key_size, value_size,
 412                                   flags, value_fd);
 413         } else if (is_prefix(*argv, "value")) {
 414                 int fd;
 415
 416                 if (!value) {
 417                         if (value_size)
 418                                 p_err("duplicate value");
 419                         else
 420                                 p_err("unnecessary value");
 421                         return -1;
 422                 }
 423
 424                 argv++;
 425
 426                 if (map_is_map_of_maps(info->type)) {
 427                         int argc = 2;
 428
 429                         if (value_size != 4) {
 430                                 p_err("value smaller than 4B for map in map?");
 431                                 return -1;
 432                         }
 433                         if (!argv[0] || !argv[1]) {
 434                                 p_err("not enough value arguments for map in map");
 435                                 return -1;
 436                         }
 437
 438                         fd = map_parse_fd(&argc, &argv);
 439                         if (fd < 0)
 440                                 return -1;
 441
 442                         *value_fd = value;
 443                         **value_fd = fd;
 444                 } else if (map_is_map_of_progs(info->type)) {
 445                         int argc = 2;
 446
 447                         if (value_size != 4) {
 448                                 p_err("value smaller than 4B for map of progs?");
 449                                 return -1;
 450                         }
 451                         if (!argv[0] || !argv[1]) {
 452                                 p_err("not enough value arguments for map of progs");
 453                                 return -1;
 454                         }
 455
 456                         fd = prog_parse_fd(&argc, &argv);
 457                         if (fd < 0)
 458                                 return -1;
 459
 460                         *value_fd = value;
 461                         **value_fd = fd;
 462                 } else {
 463                         argv = parse_bytes(argv, "value", value, value_size);
 464                         if (!argv)
 465                                 return -1;
 466
 467                         fill_per_cpu_value(info, value);
 468                 }
 469
 470                 return parse_elem(argv, info, key, NULL, key_size, value_size,
 471                                   flags, NULL);
 472         } else if (is_prefix(*argv, "any") || is_prefix(*argv, "noexist") ||
 473                    is_prefix(*argv, "exist")) {
 474                 if (!flags) {
 475                         p_err("flags specified multiple times: %s", *argv);
 476                         return -1;
 477                 }
 478
 479                 if (is_prefix(*argv, "any"))
 480                         *flags = BPF_ANY;
 481                 else if (is_prefix(*argv, "noexist"))
 482                         *flags = BPF_NOEXIST;
 483                 else if (is_prefix(*argv, "exist"))
 484                         *flags = BPF_EXIST;
 485
 486                 return parse_elem(argv + 1, info, key, value, key_size,
 487                                   value_size, NULL, value_fd);
 488         }
 489
 490         p_err("expected key or value, got: %s", *argv);
 491         return -1;
 492 }
 493
 494 static int show_map_close_json(int fd, struct bpf_map_info *info)
 495 {
 496         char *memlock;
 497
 498         memlock = get_fdinfo(fd, "memlock");
 499         close(fd);
 500
 501         jsonw_start_object(json_wtr);
 502
 503         jsonw_uint_field(json_wtr, "id", info->id);
 504         if (info->type < ARRAY_SIZE(map_type_name))
 505                 jsonw_string_field(json_wtr, "type",
 506                                    map_type_name[info->type]);
 507         else
 508                 jsonw_uint_field(json_wtr, "type", info->type);
 509
 510         if (*info->name)
 511                 jsonw_string_field(json_wtr, "name", info->name);
 512
 513         jsonw_name(json_wtr, "flags");
 514         jsonw_printf(json_wtr, "%d", info->map_flags);
 515
 516         print_dev_json(info->ifindex, info->netns_dev, info->netns_ino);
 517
 518         jsonw_uint_field(json_wtr, "bytes_key", info->key_size);
 519         jsonw_uint_field(json_wtr, "bytes_value", info->value_size);
 520         jsonw_uint_field(json_wtr, "max_entries", info->max_entries);
 521
 522         if (memlock)
 523                 jsonw_int_field(json_wtr, "bytes_memlock", atoi(memlock));
 524         free(memlock);
 525
 526         if (!hash_empty(map_table.table)) {
 527                 struct pinned_obj *obj;
 528
 529                 jsonw_name(json_wtr, "pinned");
 530                 jsonw_start_array(json_wtr);
 531                 hash_for_each_possible(map_table.table, obj, hash, info->id) {
 532                         if (obj->id == info->id)
 533                                 jsonw_string(json_wtr, obj->path);
 534                 }
 535                 jsonw_end_array(json_wtr);
 536         }
 537
 538         jsonw_end_object(json_wtr);
 539
 540         return 0;
 541 }
 542
 543 static int show_map_close_plain(int fd, struct bpf_map_info *info)
 544 {
 545         char *memlock;
 546
 547         memlock = get_fdinfo(fd, "memlock");
 548         close(fd);
 549
 550         printf("%u: ", info->id);
 551         if (info->type < ARRAY_SIZE(map_type_name))
 552                 printf("%s  ", map_type_name[info->type]);
 553         else
 554                 printf("type %u  ", info->type);
 555
 556         if (*info->name)
 557                 printf("name %s  ", info->name);
 558
 559         printf("flags 0x%x", info->map_flags);
 560         print_dev_plain(info->ifindex, info->netns_dev, info->netns_ino);
 561         printf("\n");
 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         printf("\n");
 570         if (!hash_empty(map_table.table)) {
 571                 struct pinned_obj *obj;
 572
 573                 hash_for_each_possible(map_table.table, obj, hash, info->id) {
 574                         if (obj->id == info->id)
 575                                 printf("\tpinned %s\n", obj->path);
 576                 }
 577         }
 578         return 0;
 579 }
 580
 581 static int do_show(int argc, char **argv)
 582 {
 583         struct bpf_map_info info = {};
 584         __u32 len = sizeof(info);
 585         __u32 id = 0;
 586         int err;
 587         int fd;
 588
 589         if (show_pinned)
 590                 build_pinned_obj_table(&map_table, BPF_OBJ_MAP);
 591
 592         if (argc == 2) {
 593                 fd = map_parse_fd_and_info(&argc, &argv, &info, &len);
 594                 if (fd < 0)
 595                         return -1;
 596
 597                 if (json_output)
 598                         return show_map_close_json(fd, &info);
 599                 else
 600                         return show_map_close_plain(fd, &info);
 601         }
 602
 603         if (argc)
 604                 return BAD_ARG();
 605
 606         if (json_output)
 607                 jsonw_start_array(json_wtr);
 608         while (true) {
 609                 err = bpf_map_get_next_id(id, &id);
 610                 if (err) {
 611                         if (errno == ENOENT)
 612                                 break;
 613                         p_err("can't get next map: %s%s", strerror(errno),
 614                               errno == EINVAL ? " -- kernel too old?" : "");
 615                         break;
 616                 }
 617
 618                 fd = bpf_map_get_fd_by_id(id);
 619                 if (fd < 0) {
 620                         if (errno == ENOENT)
 621                                 continue;
 622                         p_err("can't get map by id (%u): %s",
 623                               id, strerror(errno));
 624                         break;
 625                 }
 626
 627                 err = bpf_obj_get_info_by_fd(fd, &info, &len);
 628                 if (err) {
 629                         p_err("can't get map info: %s", strerror(errno));
 630                         close(fd);
 631                         break;
 632                 }
 633
 634                 if (json_output)
 635                         show_map_close_json(fd, &info);
 636                 else
 637                         show_map_close_plain(fd, &info);
 638         }
 639         if (json_output)
 640                 jsonw_end_array(json_wtr);
 641
 642         return errno == ENOENT ? 0 : -1;
 643 }
 644
 645 static int do_dump(int argc, char **argv)
 646 {
 647         struct bpf_map_info info = {};
 648         void *key, *value, *prev_key;
 649         unsigned int num_elems = 0;
 650         __u32 len = sizeof(info);
 651         json_writer_t *btf_wtr;
 652         struct btf *btf = NULL;
 653         int err;
 654         int fd;
 655
 656         if (argc != 2)
 657                 usage();
 658
 659         fd = map_parse_fd_and_info(&argc, &argv, &info, &len);
 660         if (fd < 0)
 661                 return -1;
 662
 663         if (map_is_map_of_maps(info.type) || map_is_map_of_progs(info.type)) {
 664                 p_err("Dumping maps of maps and program maps not supported");
 665                 close(fd);
 666                 return -1;
 667         }
 668
 669         key = malloc(info.key_size);
 670         value = alloc_value(&info);
 671         if (!key || !value) {
 672                 p_err("mem alloc failed");
 673                 err = -1;
 674                 goto exit_free;
 675         }
 676
 677         prev_key = NULL;
 678
 679         err = get_btf(&info, &btf);
 680         if (err) {
 681                 p_err("failed to get btf");
 682                 goto exit_free;
 683         }
 684
 685         if (json_output)
 686                 jsonw_start_array(json_wtr);
 687         else
 688                 if (btf) {
 689                         btf_wtr = get_btf_writer();
 690                         if (!btf_wtr) {
 691                                 p_info("failed to create json writer for btf. falling back to plain output");
 692                                 btf__free(btf);
 693                                 btf = NULL;
 694                         } else {
 695                                 jsonw_start_array(btf_wtr);
 696                         }
 697                 }
 698
 699         while (true) {
 700                 err = bpf_map_get_next_key(fd, prev_key, key);
 701                 if (err) {
 702                         if (errno == ENOENT)
 703                                 err = 0;
 704                         break;
 705                 }
 706
 707                 if (!bpf_map_lookup_elem(fd, key, value)) {
 708                         if (json_output)
 709                                 print_entry_json(&info, key, value, btf);
 710                         else
 711                                 if (btf) {
 712                                         struct btf_dumper d = {
 713                                                 .btf = btf,
 714                                                 .jw = btf_wtr,
 715                                                 .is_plain_text = true,
 716                                         };
 717
 718                                         do_dump_btf(&d, &info, key, value);
 719                                 } else {
 720                                         print_entry_plain(&info, key, value);
 721                                 }
 722                 } else {
 723                         if (json_output) {
 724                                 jsonw_name(json_wtr, "key");
 725                                 print_hex_data_json(key, info.key_size);
 726                                 jsonw_name(json_wtr, "value");
 727                                 jsonw_start_object(json_wtr);
 728                                 jsonw_string_field(json_wtr, "error",
 729                                                    "can't lookup element");
 730                                 jsonw_end_object(json_wtr);
 731                         } else {
 732                                 p_info("can't lookup element with key: ");
 733                                 fprint_hex(stderr, key, info.key_size, " ");
 734                                 fprintf(stderr, "\n");
 735                         }
 736                 }
 737
 738                 prev_key = key;
 739                 num_elems++;
 740         }
 741
 742         if (json_output)
 743                 jsonw_end_array(json_wtr);
 744         else if (btf) {
 745                 jsonw_end_array(btf_wtr);
 746                 jsonw_destroy(&btf_wtr);
 747         } else {
 748                 printf("Found %u element%s\n", num_elems,
 749                        num_elems != 1 ? "s" : "");
 750         }
 751
 752 exit_free:
 753         free(key);
 754         free(value);
 755         close(fd);
 756         btf__free(btf);
 757
 758         return err;
 759 }
 760
 761 static int do_update(int argc, char **argv)
 762 {
 763         struct bpf_map_info info = {};
 764         __u32 len = sizeof(info);
 765         __u32 *value_fd = NULL;
 766         __u32 flags = BPF_ANY;
 767         void *key, *value;
 768         int fd, err;
 769
 770         if (argc < 2)
 771                 usage();
 772
 773         fd = map_parse_fd_and_info(&argc, &argv, &info, &len);
 774         if (fd < 0)
 775                 return -1;
 776
 777         key = malloc(info.key_size);
 778         value = alloc_value(&info);
 779         if (!key || !value) {
 780                 p_err("mem alloc failed");
 781                 err = -1;
 782                 goto exit_free;
 783         }
 784
 785         err = parse_elem(argv, &info, key, value, info.key_size,
 786                          info.value_size, &flags, &value_fd);
 787         if (err)
 788                 goto exit_free;
 789
 790         err = bpf_map_update_elem(fd, key, value, flags);
 791         if (err) {
 792                 p_err("update failed: %s", strerror(errno));
 793                 goto exit_free;
 794         }
 795
 796 exit_free:
 797         if (value_fd)
 798                 close(*value_fd);
 799         free(key);
 800         free(value);
 801         close(fd);
 802
 803         if (!err && json_output)
 804                 jsonw_null(json_wtr);
 805         return err;
 806 }
 807
 808 static int do_lookup(int argc, char **argv)
 809 {
 810         struct bpf_map_info info = {};
 811         __u32 len = sizeof(info);
 812         json_writer_t *btf_wtr;
 813         struct btf *btf = NULL;
 814         void *key, *value;
 815         int err;
 816         int fd;
 817
 818         if (argc < 2)
 819                 usage();
 820
 821         fd = map_parse_fd_and_info(&argc, &argv, &info, &len);
 822         if (fd < 0)
 823                 return -1;
 824
 825         key = malloc(info.key_size);
 826         value = alloc_value(&info);
 827         if (!key || !value) {
 828                 p_err("mem alloc failed");
 829                 err = -1;
 830                 goto exit_free;
 831         }
 832
 833         err = parse_elem(argv, &info, key, NULL, info.key_size, 0, NULL, NULL);
 834         if (err)
 835                 goto exit_free;
 836
 837         err = bpf_map_lookup_elem(fd, key, value);
 838         if (err) {
 839                 if (errno == ENOENT) {
 840                         if (json_output) {
 841                                 jsonw_null(json_wtr);
 842                         } else {
 843                                 printf("key:\n");
 844                                 fprint_hex(stdout, key, info.key_size, " ");
 845                                 printf("\n\nNot found\n");
 846                         }
 847                 } else {
 848                         p_err("lookup failed: %s", strerror(errno));
 849                 }
 850
 851                 goto exit_free;
 852         }
 853
 854         /* here means bpf_map_lookup_elem() succeeded */
 855         err = get_btf(&info, &btf);
 856         if (err) {
 857                 p_err("failed to get btf");
 858                 goto exit_free;
 859         }
 860
 861         if (json_output) {
 862                 print_entry_json(&info, key, value, btf);
 863         } else if (btf) {
 864                 /* if here json_wtr wouldn't have been initialised,
 865                  * so let's create separate writer for btf
 866                  */
 867                 btf_wtr = get_btf_writer();
 868                 if (!btf_wtr) {
 869                         p_info("failed to create json writer for btf. falling back to plain output");
 870                         btf__free(btf);
 871                         btf = NULL;
 872                         print_entry_plain(&info, key, value);
 873                 } else {
 874                         struct btf_dumper d = {
 875                                 .btf = btf,
 876                                 .jw = btf_wtr,
 877                                 .is_plain_text = true,
 878                         };
 879
 880                         do_dump_btf(&d, &info, key, value);
 881                         jsonw_destroy(&btf_wtr);
 882                 }
 883         } else {
 884                 print_entry_plain(&info, key, value);
 885         }
 886
 887 exit_free:
 888         free(key);
 889         free(value);
 890         close(fd);
 891         btf__free(btf);
 892
 893         return err;
 894 }
 895
 896 static int do_getnext(int argc, char **argv)
 897 {
 898         struct bpf_map_info info = {};
 899         __u32 len = sizeof(info);
 900         void *key, *nextkey;
 901         int err;
 902         int fd;
 903
 904         if (argc < 2)
 905                 usage();
 906
 907         fd = map_parse_fd_and_info(&argc, &argv, &info, &len);
 908         if (fd < 0)
 909                 return -1;
 910
 911         key = malloc(info.key_size);
 912         nextkey = malloc(info.key_size);
 913         if (!key || !nextkey) {
 914                 p_err("mem alloc failed");
 915                 err = -1;
 916                 goto exit_free;
 917         }
 918
 919         if (argc) {
 920                 err = parse_elem(argv, &info, key, NULL, info.key_size, 0,
 921                                  NULL, NULL);
 922                 if (err)
 923                         goto exit_free;
 924         } else {
 925                 free(key);
 926                 key = NULL;
 927         }
 928
 929         err = bpf_map_get_next_key(fd, key, nextkey);
 930         if (err) {
 931                 p_err("can't get next key: %s", strerror(errno));
 932                 goto exit_free;
 933         }
 934
 935         if (json_output) {
 936                 jsonw_start_object(json_wtr);
 937                 if (key) {
 938                         jsonw_name(json_wtr, "key");
 939                         print_hex_data_json(key, info.key_size);
 940                 } else {
 941                         jsonw_null_field(json_wtr, "key");
 942                 }
 943                 jsonw_name(json_wtr, "next_key");
 944                 print_hex_data_json(nextkey, info.key_size);
 945                 jsonw_end_object(json_wtr);
 946         } else {
 947                 if (key) {
 948                         printf("key:\n");
 949                         fprint_hex(stdout, key, info.key_size, " ");
 950                         printf("\n");
 951                 } else {
 952                         printf("key: None\n");
 953                 }
 954                 printf("next key:\n");
 955                 fprint_hex(stdout, nextkey, info.key_size, " ");
 956                 printf("\n");
 957         }
 958
 959 exit_free:
 960         free(nextkey);
 961         free(key);
 962         close(fd);
 963
 964         return err;
 965 }
 966
 967 static int do_delete(int argc, char **argv)
 968 {
 969         struct bpf_map_info info = {};
 970         __u32 len = sizeof(info);
 971         void *key;
 972         int err;
 973         int fd;
 974
 975         if (argc < 2)
 976                 usage();
 977
 978         fd = map_parse_fd_and_info(&argc, &argv, &info, &len);
 979         if (fd < 0)
 980                 return -1;
 981
 982         key = malloc(info.key_size);
 983         if (!key) {
 984                 p_err("mem alloc failed");
 985                 err = -1;
 986                 goto exit_free;
 987         }
 988
 989         err = parse_elem(argv, &info, key, NULL, info.key_size, 0, NULL, NULL);
 990         if (err)
 991                 goto exit_free;
 992
 993         err = bpf_map_delete_elem(fd, key);
 994         if (err)
 995                 p_err("delete failed: %s", strerror(errno));
 996
 997 exit_free:
 998         free(key);
 999         close(fd);
1000
1001         if (!err && json_output)
1002                 jsonw_null(json_wtr);
1003         return err;
1004 }
1005
1006 static int do_pin(int argc, char **argv)
1007 {
1008         int err;
1009
1010         err = do_pin_any(argc, argv, bpf_map_get_fd_by_id);
1011         if (!err && json_output)
1012                 jsonw_null(json_wtr);
1013         return err;
1014 }
1015
1016 static int do_help(int argc, char **argv)
1017 {
1018         if (json_output) {
1019                 jsonw_null(json_wtr);
1020                 return 0;
1021         }
1022
1023         fprintf(stderr,
1024                 "Usage: %s %s { show | list }   [MAP]\n"
1025                 "       %s %s dump       MAP\n"
1026                 "       %s %s update     MAP  key DATA value VALUE [UPDATE_FLAGS]\n"
1027                 "       %s %s lookup     MAP  key DATA\n"
1028                 "       %s %s getnext    MAP [key DATA]\n"
1029                 "       %s %s delete     MAP  key DATA\n"
1030                 "       %s %s pin        MAP  FILE\n"
1031                 "       %s %s event_pipe MAP [cpu N index M]\n"
1032                 "       %s %s help\n"
1033                 "\n"
1034                 "       " HELP_SPEC_MAP "\n"
1035                 "       DATA := { [hex] BYTES }\n"
1036                 "       " HELP_SPEC_PROGRAM "\n"
1037                 "       VALUE := { DATA | MAP | PROG }\n"
1038                 "       UPDATE_FLAGS := { any | exist | noexist }\n"
1039                 "       " HELP_SPEC_OPTIONS "\n"
1040                 "",
1041                 bin_name, argv[-2], bin_name, argv[-2], bin_name, argv[-2],
1042                 bin_name, argv[-2], bin_name, argv[-2], bin_name, argv[-2],
1043                 bin_name, argv[-2], bin_name, argv[-2], bin_name, argv[-2]);
1044
1045         return 0;
1046 }
1047
1048 static const struct cmd cmds[] = {
1049         { "show",       do_show },
1050         { "list",       do_show },
1051         { "help",       do_help },
1052         { "dump",       do_dump },
1053         { "update",     do_update },
1054         { "lookup",     do_lookup },
1055         { "getnext",    do_getnext },
1056         { "delete",     do_delete },
1057         { "pin",        do_pin },
1058         { "event_pipe", do_event_pipe },
1059         { 0 }
1060 };
1061
1062 int do_map(int argc, char **argv)
1063 {
1064         return cmd_select(cmds, argc, argv, do_help);
1065 }