tools/bpf/bpftool/map.c

   1 /*
   2  * Copyright (C) 2017 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 /* Author: Jakub Kicinski <kubakici@wp.pl> */
  35
  36 #include <assert.h>
  37 #include <ctype.h>
  38 #include <errno.h>
  39 #include <fcntl.h>
  40 #include <stdbool.h>
  41 #include <stdio.h>
  42 #include <stdlib.h>
  43 #include <string.h>
  44 #include <unistd.h>
  45 #include <sys/types.h>
  46 #include <sys/stat.h>
  47
  48 #include <bpf.h>
  49
  50 #include "main.h"
  51
  52 static const char * const map_type_name[] = {
  53         [BPF_MAP_TYPE_UNSPEC]           = "unspec",
  54         [BPF_MAP_TYPE_HASH]             = "hash",
  55         [BPF_MAP_TYPE_ARRAY]            = "array",
  56         [BPF_MAP_TYPE_PROG_ARRAY]       = "prog_array",
  57         [BPF_MAP_TYPE_PERF_EVENT_ARRAY] = "perf_event_array",
  58         [BPF_MAP_TYPE_PERCPU_HASH]      = "percpu_hash",
  59         [BPF_MAP_TYPE_PERCPU_ARRAY]     = "percpu_array",
  60         [BPF_MAP_TYPE_STACK_TRACE]      = "stack_trace",
  61         [BPF_MAP_TYPE_CGROUP_ARRAY]     = "cgroup_array",
  62         [BPF_MAP_TYPE_LRU_HASH]         = "lru_hash",
  63         [BPF_MAP_TYPE_LRU_PERCPU_HASH]  = "lru_percpu_hash",
  64         [BPF_MAP_TYPE_LPM_TRIE]         = "lpm_trie",
  65         [BPF_MAP_TYPE_ARRAY_OF_MAPS]    = "array_of_maps",
  66         [BPF_MAP_TYPE_HASH_OF_MAPS]     = "hash_of_maps",
  67         [BPF_MAP_TYPE_DEVMAP]           = "devmap",
  68         [BPF_MAP_TYPE_SOCKMAP]          = "sockmap",
  69 };
  70
  71 static unsigned int get_possible_cpus(void)
  72 {
  73         static unsigned int result;
  74         char buf[128];
  75         long int n;
  76         char *ptr;
  77         int fd;
  78
  79         if (result)
  80                 return result;
  81
  82         fd = open("/sys/devices/system/cpu/possible", O_RDONLY);
  83         if (fd < 0) {
  84                 p_err("can't open sysfs possible cpus");
  85                 exit(-1);
  86         }
  87
  88         n = read(fd, buf, sizeof(buf));
  89         if (n < 2) {
  90                 p_err("can't read sysfs possible cpus");
  91                 exit(-1);
  92         }
  93         close(fd);
  94
  95         if (n == sizeof(buf)) {
  96                 p_err("read sysfs possible cpus overflow");
  97                 exit(-1);
  98         }
  99
 100         ptr = buf;
 101         n = 0;
 102         while (*ptr && *ptr != '\n') {
 103                 unsigned int a, b;
 104
 105                 if (sscanf(ptr, "%u-%u", &a, &b) == 2) {
 106                         n += b - a + 1;
 107
 108                         ptr = strchr(ptr, '-') + 1;
 109                 } else if (sscanf(ptr, "%u", &a) == 1) {
 110                         n++;
 111                 } else {
 112                         assert(0);
 113                 }
 114
 115                 while (isdigit(*ptr))
 116                         ptr++;
 117                 if (*ptr == ',')
 118                         ptr++;
 119         }
 120
 121         result = n;
 122
 123         return result;
 124 }
 125
 126 static bool map_is_per_cpu(__u32 type)
 127 {
 128         return type == BPF_MAP_TYPE_PERCPU_HASH ||
 129                type == BPF_MAP_TYPE_PERCPU_ARRAY ||
 130                type == BPF_MAP_TYPE_LRU_PERCPU_HASH;
 131 }
 132
 133 static bool map_is_map_of_maps(__u32 type)
 134 {
 135         return type == BPF_MAP_TYPE_ARRAY_OF_MAPS ||
 136                type == BPF_MAP_TYPE_HASH_OF_MAPS;
 137 }
 138
 139 static bool map_is_map_of_progs(__u32 type)
 140 {
 141         return type == BPF_MAP_TYPE_PROG_ARRAY;
 142 }
 143
 144 static void *alloc_value(struct bpf_map_info *info)
 145 {
 146         if (map_is_per_cpu(info->type))
 147                 return malloc(info->value_size * get_possible_cpus());
 148         else
 149                 return malloc(info->value_size);
 150 }
 151
 152 static int map_parse_fd(int *argc, char ***argv)
 153 {
 154         int fd;
 155
 156         if (is_prefix(**argv, "id")) {
 157                 unsigned int id;
 158                 char *endptr;
 159
 160                 NEXT_ARGP();
 161
 162                 id = strtoul(**argv, &endptr, 0);
 163                 if (*endptr) {
 164                         p_err("can't parse %s as ID", **argv);
 165                         return -1;
 166                 }
 167                 NEXT_ARGP();
 168
 169                 fd = bpf_map_get_fd_by_id(id);
 170                 if (fd < 0)
 171                         p_err("get map by id (%u): %s", id, strerror(errno));
 172                 return fd;
 173         } else if (is_prefix(**argv, "pinned")) {
 174                 char *path;
 175
 176                 NEXT_ARGP();
 177
 178                 path = **argv;
 179                 NEXT_ARGP();
 180
 181                 return open_obj_pinned_any(path, BPF_OBJ_MAP);
 182         }
 183
 184         p_err("expected 'id' or 'pinned', got: '%s'?", **argv);
 185         return -1;
 186 }
 187
 188 static int
 189 map_parse_fd_and_info(int *argc, char ***argv, void *info, __u32 *info_len)
 190 {
 191         int err;
 192         int fd;
 193
 194         fd = map_parse_fd(argc, argv);
 195         if (fd < 0)
 196                 return -1;
 197
 198         err = bpf_obj_get_info_by_fd(fd, info, info_len);
 199         if (err) {
 200                 p_err("can't get map info: %s", strerror(errno));
 201                 close(fd);
 202                 return err;
 203         }
 204
 205         return fd;
 206 }
 207
 208 static void print_entry_json(struct bpf_map_info *info, unsigned char *key,
 209                              unsigned char *value)
 210 {
 211         jsonw_start_object(json_wtr);
 212
 213         if (!map_is_per_cpu(info->type)) {
 214                 jsonw_name(json_wtr, "key");
 215                 print_hex_data_json(key, info->key_size);
 216                 jsonw_name(json_wtr, "value");
 217                 print_hex_data_json(value, info->value_size);
 218         } else {
 219                 unsigned int i, n;
 220
 221                 n = get_possible_cpus();
 222
 223                 jsonw_name(json_wtr, "key");
 224                 print_hex_data_json(key, info->key_size);
 225
 226                 jsonw_name(json_wtr, "values");
 227                 jsonw_start_array(json_wtr);
 228                 for (i = 0; i < n; i++) {
 229                         jsonw_start_object(json_wtr);
 230
 231                         jsonw_int_field(json_wtr, "cpu", i);
 232
 233                         jsonw_name(json_wtr, "value");
 234                         print_hex_data_json(value + i * info->value_size,
 235                                             info->value_size);
 236
 237                         jsonw_end_object(json_wtr);
 238                 }
 239                 jsonw_end_array(json_wtr);
 240         }
 241
 242         jsonw_end_object(json_wtr);
 243 }
 244
 245 static void print_entry_plain(struct bpf_map_info *info, unsigned char *key,
 246                               unsigned char *value)
 247 {
 248         if (!map_is_per_cpu(info->type)) {
 249                 bool single_line, break_names;
 250
 251                 break_names = info->key_size > 16 || info->value_size > 16;
 252                 single_line = info->key_size + info->value_size <= 24 &&
 253                         !break_names;
 254
 255                 printf("key:%c", break_names ? '\n' : ' ');
 256                 fprint_hex(stdout, key, info->key_size, " ");
 257
 258                 printf(single_line ? "  " : "\n");
 259
 260                 printf("value:%c", break_names ? '\n' : ' ');
 261                 fprint_hex(stdout, value, info->value_size, " ");
 262
 263                 printf("\n");
 264         } else {
 265                 unsigned int i, n;
 266
 267                 n = get_possible_cpus();
 268
 269                 printf("key:\n");
 270                 fprint_hex(stdout, key, info->key_size, " ");
 271                 printf("\n");
 272                 for (i = 0; i < n; i++) {
 273                         printf("value (CPU %02d):%c",
 274                                i, info->value_size > 16 ? '\n' : ' ');
 275                         fprint_hex(stdout, value + i * info->value_size,
 276                                    info->value_size, " ");
 277                         printf("\n");
 278                 }
 279         }
 280 }
 281
 282 static char **parse_bytes(char **argv, const char *name, unsigned char *val,
 283                           unsigned int n)
 284 {
 285         unsigned int i = 0;
 286         char *endptr;
 287
 288         while (i < n && argv[i]) {
 289                 val[i] = strtoul(argv[i], &endptr, 0);
 290                 if (*endptr) {
 291                         p_err("error parsing byte: %s", argv[i]);
 292                         return NULL;
 293                 }
 294                 i++;
 295         }
 296
 297         if (i != n) {
 298                 p_err("%s expected %d bytes got %d", name, n, i);
 299                 return NULL;
 300         }
 301
 302         return argv + i;
 303 }
 304
 305 static int parse_elem(char **argv, struct bpf_map_info *info,
 306                       void *key, void *value, __u32 key_size, __u32 value_size,
 307                       __u32 *flags, __u32 **value_fd)
 308 {
 309         if (!*argv) {
 310                 if (!key && !value)
 311                         return 0;
 312                 p_err("did not find %s", key ? "key" : "value");
 313                 return -1;
 314         }
 315
 316         if (is_prefix(*argv, "key")) {
 317                 if (!key) {
 318                         if (key_size)
 319                                 p_err("duplicate key");
 320                         else
 321                                 p_err("unnecessary key");
 322                         return -1;
 323                 }
 324
 325                 argv = parse_bytes(argv + 1, "key", key, key_size);
 326                 if (!argv)
 327                         return -1;
 328
 329                 return parse_elem(argv, info, NULL, value, key_size, value_size,
 330                                   flags, value_fd);
 331         } else if (is_prefix(*argv, "value")) {
 332                 int fd;
 333
 334                 if (!value) {
 335                         if (value_size)
 336                                 p_err("duplicate value");
 337                         else
 338                                 p_err("unnecessary value");
 339                         return -1;
 340                 }
 341
 342                 argv++;
 343
 344                 if (map_is_map_of_maps(info->type)) {
 345                         int argc = 2;
 346
 347                         if (value_size != 4) {
 348                                 p_err("value smaller than 4B for map in map?");
 349                                 return -1;
 350                         }
 351                         if (!argv[0] || !argv[1]) {
 352                                 p_err("not enough value arguments for map in map");
 353                                 return -1;
 354                         }
 355
 356                         fd = map_parse_fd(&argc, &argv);
 357                         if (fd < 0)
 358                                 return -1;
 359
 360                         *value_fd = value;
 361                         **value_fd = fd;
 362                 } else if (map_is_map_of_progs(info->type)) {
 363                         int argc = 2;
 364
 365                         if (value_size != 4) {
 366                                 p_err("value smaller than 4B for map of progs?");
 367                                 return -1;
 368                         }
 369                         if (!argv[0] || !argv[1]) {
 370                                 p_err("not enough value arguments for map of progs");
 371                                 return -1;
 372                         }
 373
 374                         fd = prog_parse_fd(&argc, &argv);
 375                         if (fd < 0)
 376                                 return -1;
 377
 378                         *value_fd = value;
 379                         **value_fd = fd;
 380                 } else {
 381                         argv = parse_bytes(argv, "value", value, value_size);
 382                         if (!argv)
 383                                 return -1;
 384                 }
 385
 386                 return parse_elem(argv, info, key, NULL, key_size, value_size,
 387                                   flags, NULL);
 388         } else if (is_prefix(*argv, "any") || is_prefix(*argv, "noexist") ||
 389                    is_prefix(*argv, "exist")) {
 390                 if (!flags) {
 391                         p_err("flags specified multiple times: %s", *argv);
 392                         return -1;
 393                 }
 394
 395                 if (is_prefix(*argv, "any"))
 396                         *flags = BPF_ANY;
 397                 else if (is_prefix(*argv, "noexist"))
 398                         *flags = BPF_NOEXIST;
 399                 else if (is_prefix(*argv, "exist"))
 400                         *flags = BPF_EXIST;
 401
 402                 return parse_elem(argv + 1, info, key, value, key_size,
 403                                   value_size, NULL, value_fd);
 404         }
 405
 406         p_err("expected key or value, got: %s", *argv);
 407         return -1;
 408 }
 409
 410 static int show_map_close_json(int fd, struct bpf_map_info *info)
 411 {
 412         char *memlock;
 413
 414         memlock = get_fdinfo(fd, "memlock");
 415         close(fd);
 416
 417         jsonw_start_object(json_wtr);
 418
 419         jsonw_uint_field(json_wtr, "id", info->id);
 420         if (info->type < ARRAY_SIZE(map_type_name))
 421                 jsonw_string_field(json_wtr, "type",
 422                                    map_type_name[info->type]);
 423         else
 424                 jsonw_uint_field(json_wtr, "type", info->type);
 425
 426         if (*info->name)
 427                 jsonw_string_field(json_wtr, "name", info->name);
 428
 429         jsonw_name(json_wtr, "flags");
 430         jsonw_printf(json_wtr, "%#x", info->map_flags);
 431         jsonw_uint_field(json_wtr, "bytes_key", info->key_size);
 432         jsonw_uint_field(json_wtr, "bytes_value", info->value_size);
 433         jsonw_uint_field(json_wtr, "max_entries", info->max_entries);
 434
 435         if (memlock)
 436                 jsonw_int_field(json_wtr, "bytes_memlock", atoi(memlock));
 437         free(memlock);
 438
 439         if (!hash_empty(map_table.table)) {
 440                 struct pinned_obj *obj;
 441
 442                 jsonw_name(json_wtr, "pinned");
 443                 jsonw_start_array(json_wtr);
 444                 hash_for_each_possible(map_table.table, obj, hash, info->id) {
 445                         if (obj->id == info->id)
 446                                 jsonw_string(json_wtr, obj->path);
 447                 }
 448                 jsonw_end_array(json_wtr);
 449         }
 450
 451         jsonw_end_object(json_wtr);
 452
 453         return 0;
 454 }
 455
 456 static int show_map_close_plain(int fd, struct bpf_map_info *info)
 457 {
 458         char *memlock;
 459
 460         memlock = get_fdinfo(fd, "memlock");
 461         close(fd);
 462
 463         printf("%u: ", info->id);
 464         if (info->type < ARRAY_SIZE(map_type_name))
 465                 printf("%s  ", map_type_name[info->type]);
 466         else
 467                 printf("type %u  ", info->type);
 468
 469         if (*info->name)
 470                 printf("name %s  ", info->name);
 471
 472         printf("flags 0x%x\n", info->map_flags);
 473         printf("\tkey %uB  value %uB  max_entries %u",
 474                info->key_size, info->value_size, info->max_entries);
 475
 476         if (memlock)
 477                 printf("  memlock %sB", memlock);
 478         free(memlock);
 479
 480         printf("\n");
 481         if (!hash_empty(map_table.table)) {
 482                 struct pinned_obj *obj;
 483
 484                 hash_for_each_possible(map_table.table, obj, hash, info->id) {
 485                         if (obj->id == info->id)
 486                                 printf("\tpinned %s\n", obj->path);
 487                 }
 488         }
 489         return 0;
 490 }
 491
 492 static int do_show(int argc, char **argv)
 493 {
 494         struct bpf_map_info info = {};
 495         __u32 len = sizeof(info);
 496         __u32 id = 0;
 497         int err;
 498         int fd;
 499
 500         if (show_pinned)
 501                 build_pinned_obj_table(&map_table, BPF_OBJ_MAP);
 502
 503         if (argc == 2) {
 504                 fd = map_parse_fd_and_info(&argc, &argv, &info, &len);
 505                 if (fd < 0)
 506                         return -1;
 507
 508                 if (json_output)
 509                         return show_map_close_json(fd, &info);
 510                 else
 511                         return show_map_close_plain(fd, &info);
 512         }
 513
 514         if (argc)
 515                 return BAD_ARG();
 516
 517         if (json_output)
 518                 jsonw_start_array(json_wtr);
 519         while (true) {
 520                 err = bpf_map_get_next_id(id, &id);
 521                 if (err) {
 522                         if (errno == ENOENT)
 523                                 break;
 524                         p_err("can't get next map: %s%s", strerror(errno),
 525                               errno == EINVAL ? " -- kernel too old?" : "");
 526                         break;
 527                 }
 528
 529                 fd = bpf_map_get_fd_by_id(id);
 530                 if (fd < 0) {
 531                         if (errno == ENOENT)
 532                                 continue;
 533                         p_err("can't get map by id (%u): %s",
 534                               id, strerror(errno));
 535                         break;
 536                 }
 537
 538                 err = bpf_obj_get_info_by_fd(fd, &info, &len);
 539                 if (err) {
 540                         p_err("can't get map info: %s", strerror(errno));
 541                         close(fd);
 542                         break;
 543                 }
 544
 545                 if (json_output)
 546                         show_map_close_json(fd, &info);
 547                 else
 548                         show_map_close_plain(fd, &info);
 549         }
 550         if (json_output)
 551                 jsonw_end_array(json_wtr);
 552
 553         return errno == ENOENT ? 0 : -1;
 554 }
 555
 556 static int do_dump(int argc, char **argv)
 557 {
 558         void *key, *value, *prev_key;
 559         unsigned int num_elems = 0;
 560         struct bpf_map_info info = {};
 561         __u32 len = sizeof(info);
 562         int err;
 563         int fd;
 564
 565         if (argc != 2)
 566                 usage();
 567
 568         fd = map_parse_fd_and_info(&argc, &argv, &info, &len);
 569         if (fd < 0)
 570                 return -1;
 571
 572         if (map_is_map_of_maps(info.type) || map_is_map_of_progs(info.type)) {
 573                 p_err("Dumping maps of maps and program maps not supported");
 574                 close(fd);
 575                 return -1;
 576         }
 577
 578         key = malloc(info.key_size);
 579         value = alloc_value(&info);
 580         if (!key || !value) {
 581                 p_err("mem alloc failed");
 582                 err = -1;
 583                 goto exit_free;
 584         }
 585
 586         prev_key = NULL;
 587         if (json_output)
 588                 jsonw_start_array(json_wtr);
 589         while (true) {
 590                 err = bpf_map_get_next_key(fd, prev_key, key);
 591                 if (err) {
 592                         if (errno == ENOENT)
 593                                 err = 0;
 594                         break;
 595                 }
 596
 597                 if (!bpf_map_lookup_elem(fd, key, value)) {
 598                         if (json_output)
 599                                 print_entry_json(&info, key, value);
 600                         else
 601                                 print_entry_plain(&info, key, value);
 602                 } else {
 603                         if (json_output) {
 604                                 jsonw_name(json_wtr, "key");
 605                                 print_hex_data_json(key, info.key_size);
 606                                 jsonw_name(json_wtr, "value");
 607                                 jsonw_start_object(json_wtr);
 608                                 jsonw_string_field(json_wtr, "error",
 609                                                    "can't lookup element");
 610                                 jsonw_end_object(json_wtr);
 611                         } else {
 612                                 p_info("can't lookup element with key: ");
 613                                 fprint_hex(stderr, key, info.key_size, " ");
 614                                 fprintf(stderr, "\n");
 615                         }
 616                 }
 617
 618                 prev_key = key;
 619                 num_elems++;
 620         }
 621
 622         if (json_output)
 623                 jsonw_end_array(json_wtr);
 624         else
 625                 printf("Found %u element%s\n", num_elems,
 626                        num_elems != 1 ? "s" : "");
 627
 628 exit_free:
 629         free(key);
 630         free(value);
 631         close(fd);
 632
 633         return err;
 634 }
 635
 636 static int do_update(int argc, char **argv)
 637 {
 638         struct bpf_map_info info = {};
 639         __u32 len = sizeof(info);
 640         __u32 *value_fd = NULL;
 641         __u32 flags = BPF_ANY;
 642         void *key, *value;
 643         int fd, err;
 644
 645         if (argc < 2)
 646                 usage();
 647
 648         fd = map_parse_fd_and_info(&argc, &argv, &info, &len);
 649         if (fd < 0)
 650                 return -1;
 651
 652         key = malloc(info.key_size);
 653         value = alloc_value(&info);
 654         if (!key || !value) {
 655                 p_err("mem alloc failed");
 656                 err = -1;
 657                 goto exit_free;
 658         }
 659
 660         err = parse_elem(argv, &info, key, value, info.key_size,
 661                          info.value_size, &flags, &value_fd);
 662         if (err)
 663                 goto exit_free;
 664
 665         err = bpf_map_update_elem(fd, key, value, flags);
 666         if (err) {
 667                 p_err("update failed: %s", strerror(errno));
 668                 goto exit_free;
 669         }
 670
 671 exit_free:
 672         if (value_fd)
 673                 close(*value_fd);
 674         free(key);
 675         free(value);
 676         close(fd);
 677
 678         if (!err && json_output)
 679                 jsonw_null(json_wtr);
 680         return err;
 681 }
 682
 683 static int do_lookup(int argc, char **argv)
 684 {
 685         struct bpf_map_info info = {};
 686         __u32 len = sizeof(info);
 687         void *key, *value;
 688         int err;
 689         int fd;
 690
 691         if (argc < 2)
 692                 usage();
 693
 694         fd = map_parse_fd_and_info(&argc, &argv, &info, &len);
 695         if (fd < 0)
 696                 return -1;
 697
 698         key = malloc(info.key_size);
 699         value = alloc_value(&info);
 700         if (!key || !value) {
 701                 p_err("mem alloc failed");
 702                 err = -1;
 703                 goto exit_free;
 704         }
 705
 706         err = parse_elem(argv, &info, key, NULL, info.key_size, 0, NULL, NULL);
 707         if (err)
 708                 goto exit_free;
 709
 710         err = bpf_map_lookup_elem(fd, key, value);
 711         if (!err) {
 712                 if (json_output)
 713                         print_entry_json(&info, key, value);
 714                 else
 715                         print_entry_plain(&info, key, value);
 716         } else if (errno == ENOENT) {
 717                 if (json_output) {
 718                         jsonw_null(json_wtr);
 719                 } else {
 720                         printf("key:\n");
 721                         fprint_hex(stdout, key, info.key_size, " ");
 722                         printf("\n\nNot found\n");
 723                 }
 724         } else {
 725                 p_err("lookup failed: %s", strerror(errno));
 726         }
 727
 728 exit_free:
 729         free(key);
 730         free(value);
 731         close(fd);
 732
 733         return err;
 734 }
 735
 736 static int do_getnext(int argc, char **argv)
 737 {
 738         struct bpf_map_info info = {};
 739         __u32 len = sizeof(info);
 740         void *key, *nextkey;
 741         int err;
 742         int fd;
 743
 744         if (argc < 2)
 745                 usage();
 746
 747         fd = map_parse_fd_and_info(&argc, &argv, &info, &len);
 748         if (fd < 0)
 749                 return -1;
 750
 751         key = malloc(info.key_size);
 752         nextkey = malloc(info.key_size);
 753         if (!key || !nextkey) {
 754                 p_err("mem alloc failed");
 755                 err = -1;
 756                 goto exit_free;
 757         }
 758
 759         if (argc) {
 760                 err = parse_elem(argv, &info, key, NULL, info.key_size, 0,
 761                                  NULL, NULL);
 762                 if (err)
 763                         goto exit_free;
 764         } else {
 765                 free(key);
 766                 key = NULL;
 767         }
 768
 769         err = bpf_map_get_next_key(fd, key, nextkey);
 770         if (err) {
 771                 p_err("can't get next key: %s", strerror(errno));
 772                 goto exit_free;
 773         }
 774
 775         if (json_output) {
 776                 jsonw_start_object(json_wtr);
 777                 if (key) {
 778                         jsonw_name(json_wtr, "key");
 779                         print_hex_data_json(key, info.key_size);
 780                 } else {
 781                         jsonw_null_field(json_wtr, "key");
 782                 }
 783                 jsonw_name(json_wtr, "next_key");
 784                 print_hex_data_json(nextkey, info.key_size);
 785                 jsonw_end_object(json_wtr);
 786         } else {
 787                 if (key) {
 788                         printf("key:\n");
 789                         fprint_hex(stdout, key, info.key_size, " ");
 790                         printf("\n");
 791                 } else {
 792                         printf("key: None\n");
 793                 }
 794                 printf("next key:\n");
 795                 fprint_hex(stdout, nextkey, info.key_size, " ");
 796                 printf("\n");
 797         }
 798
 799 exit_free:
 800         free(nextkey);
 801         free(key);
 802         close(fd);
 803
 804         return err;
 805 }
 806
 807 static int do_delete(int argc, char **argv)
 808 {
 809         struct bpf_map_info info = {};
 810         __u32 len = sizeof(info);
 811         void *key;
 812         int err;
 813         int fd;
 814
 815         if (argc < 2)
 816                 usage();
 817
 818         fd = map_parse_fd_and_info(&argc, &argv, &info, &len);
 819         if (fd < 0)
 820                 return -1;
 821
 822         key = malloc(info.key_size);
 823         if (!key) {
 824                 p_err("mem alloc failed");
 825                 err = -1;
 826                 goto exit_free;
 827         }
 828
 829         err = parse_elem(argv, &info, key, NULL, info.key_size, 0, NULL, NULL);
 830         if (err)
 831                 goto exit_free;
 832
 833         err = bpf_map_delete_elem(fd, key);
 834         if (err)
 835                 p_err("delete failed: %s", strerror(errno));
 836
 837 exit_free:
 838         free(key);
 839         close(fd);
 840
 841         if (!err && json_output)
 842                 jsonw_null(json_wtr);
 843         return err;
 844 }
 845
 846 static int do_pin(int argc, char **argv)
 847 {
 848         int err;
 849
 850         err = do_pin_any(argc, argv, bpf_map_get_fd_by_id);
 851         if (!err && json_output)
 852                 jsonw_null(json_wtr);
 853         return err;
 854 }
 855
 856 static int do_help(int argc, char **argv)
 857 {
 858         if (json_output) {
 859                 jsonw_null(json_wtr);
 860                 return 0;
 861         }
 862
 863         fprintf(stderr,
 864                 "Usage: %s %s { show | list }   [MAP]\n"
 865                 "       %s %s dump    MAP\n"
 866                 "       %s %s update  MAP  key BYTES value VALUE [UPDATE_FLAGS]\n"
 867                 "       %s %s lookup  MAP  key BYTES\n"
 868                 "       %s %s getnext MAP [key BYTES]\n"
 869                 "       %s %s delete  MAP  key BYTES\n"
 870                 "       %s %s pin     MAP  FILE\n"
 871                 "       %s %s help\n"
 872                 "\n"
 873                 "       MAP := { id MAP_ID | pinned FILE }\n"
 874                 "       " HELP_SPEC_PROGRAM "\n"
 875                 "       VALUE := { BYTES | MAP | PROG }\n"
 876                 "       UPDATE_FLAGS := { any | exist | noexist }\n"
 877                 "       " HELP_SPEC_OPTIONS "\n"
 878                 "",
 879                 bin_name, argv[-2], bin_name, argv[-2], bin_name, argv[-2],
 880                 bin_name, argv[-2], bin_name, argv[-2], bin_name, argv[-2],
 881                 bin_name, argv[-2], bin_name, argv[-2]);
 882
 883         return 0;
 884 }
 885
 886 static const struct cmd cmds[] = {
 887         { "show",       do_show },
 888         { "list",       do_show },
 889         { "help",       do_help },
 890         { "dump",       do_dump },
 891         { "update",     do_update },
 892         { "lookup",     do_lookup },
 893         { "getnext",    do_getnext },
 894         { "delete",     do_delete },
 895         { "pin",        do_pin },
 896         { 0 }
 897 };
 898
 899 int do_map(int argc, char **argv)
 900 {
 901         return cmd_select(cmds, argc, argv, do_help);
 902 }