root/tools/bpf/bpftool/map.c
// SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
/* Copyright (C) 2017-2018 Netronome Systems, Inc. */

#include <errno.h>
#include <fcntl.h>
#include <linux/err.h>
#include <linux/kernel.h>
#include <net/if.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/stat.h>

#include <bpf/bpf.h>
#include <bpf/btf.h>
#include <bpf/hashmap.h>

#include "json_writer.h"
#include "main.h"

static struct hashmap *map_table;

static bool map_is_per_cpu(__u32 type)
{
        return type == BPF_MAP_TYPE_PERCPU_HASH ||
               type == BPF_MAP_TYPE_PERCPU_ARRAY ||
               type == BPF_MAP_TYPE_LRU_PERCPU_HASH ||
               type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE;
}

static bool map_is_map_of_maps(__u32 type)
{
        return type == BPF_MAP_TYPE_ARRAY_OF_MAPS ||
               type == BPF_MAP_TYPE_HASH_OF_MAPS;
}

static bool map_is_map_of_progs(__u32 type)
{
        return type == BPF_MAP_TYPE_PROG_ARRAY;
}

static int map_type_from_str(const char *type)
{
        const char *map_type_str;
        unsigned int i;

        for (i = 0; ; i++) {
                map_type_str = libbpf_bpf_map_type_str(i);
                if (!map_type_str)
                        break;

                /* Don't allow prefixing in case of possible future shadowing */
                if (!strcmp(map_type_str, type))
                        return i;
        }
        return -1;
}

static void *alloc_value(struct bpf_map_info *info)
{
        if (map_is_per_cpu(info->type))
                return malloc(round_up(info->value_size, 8) *
                              get_possible_cpus());
        else
                return malloc(info->value_size);
}

static int do_dump_btf(const struct btf_dumper *d,
                       struct bpf_map_info *map_info, void *key,
                       void *value)
{
        __u32 value_id;
        int ret = 0;

        /* start of key-value pair */
        jsonw_start_object(d->jw);

        if (map_info->btf_key_type_id) {
                jsonw_name(d->jw, "key");

                ret = btf_dumper_type(d, map_info->btf_key_type_id, key);
                if (ret)
                        goto err_end_obj;
        }

        value_id = map_info->btf_vmlinux_value_type_id ?
                : map_info->btf_value_type_id;

        if (!map_is_per_cpu(map_info->type)) {
                jsonw_name(d->jw, "value");
                ret = btf_dumper_type(d, value_id, value);
        } else {
                unsigned int i, n, step;

                jsonw_name(d->jw, "values");
                jsonw_start_array(d->jw);
                n = get_possible_cpus();
                step = round_up(map_info->value_size, 8);
                for (i = 0; i < n; i++) {
                        jsonw_start_object(d->jw);
                        jsonw_int_field(d->jw, "cpu", i);
                        jsonw_name(d->jw, "value");
                        ret = btf_dumper_type(d, value_id, value + i * step);
                        jsonw_end_object(d->jw);
                        if (ret)
                                break;
                }
                jsonw_end_array(d->jw);
        }

err_end_obj:
        /* end of key-value pair */
        jsonw_end_object(d->jw);

        return ret;
}

static json_writer_t *get_btf_writer(void)
{
        json_writer_t *jw = jsonw_new(stdout);

        if (!jw)
                return NULL;
        jsonw_pretty(jw, true);

        return jw;
}

static void print_entry_json(struct bpf_map_info *info, unsigned char *key,
                             unsigned char *value, struct btf *btf)
{
        jsonw_start_object(json_wtr);

        if (!map_is_per_cpu(info->type)) {
                jsonw_name(json_wtr, "key");
                print_hex_data_json(key, info->key_size);
                jsonw_name(json_wtr, "value");
                print_hex_data_json(value, info->value_size);
                if (map_is_map_of_maps(info->type))
                        jsonw_uint_field(json_wtr, "inner_map_id",
                                         *(unsigned int *)value);
                if (btf) {
                        struct btf_dumper d = {
                                .btf = btf,
                                .jw = json_wtr,
                                .is_plain_text = false,
                        };

                        jsonw_name(json_wtr, "formatted");
                        do_dump_btf(&d, info, key, value);
                }
        } else {
                unsigned int i, n, step;

                n = get_possible_cpus();
                step = round_up(info->value_size, 8);

                jsonw_name(json_wtr, "key");
                print_hex_data_json(key, info->key_size);

                jsonw_name(json_wtr, "values");
                jsonw_start_array(json_wtr);
                for (i = 0; i < n; i++) {
                        jsonw_start_object(json_wtr);

                        jsonw_int_field(json_wtr, "cpu", i);

                        jsonw_name(json_wtr, "value");
                        print_hex_data_json(value + i * step,
                                            info->value_size);

                        jsonw_end_object(json_wtr);
                }
                jsonw_end_array(json_wtr);
                if (btf) {
                        struct btf_dumper d = {
                                .btf = btf,
                                .jw = json_wtr,
                                .is_plain_text = false,
                        };

                        jsonw_name(json_wtr, "formatted");
                        do_dump_btf(&d, info, key, value);
                }
        }

        jsonw_end_object(json_wtr);
}

static void
print_entry_error_msg(struct bpf_map_info *info, unsigned char *key,
                      const char *error_msg)
{
        int msg_size = strlen(error_msg);
        bool single_line, break_names;

        break_names = info->key_size > 16 || msg_size > 16;
        single_line = info->key_size + msg_size <= 24 && !break_names;

        printf("key:%c", break_names ? '\n' : ' ');
        fprint_hex(stdout, key, info->key_size, " ");

        printf(single_line ? "  " : "\n");

        printf("value:%c%s", break_names ? '\n' : ' ', error_msg);

        printf("\n");
}

static void
print_entry_error(struct bpf_map_info *map_info, void *key, int lookup_errno)
{
        /* For prog_array maps or arrays of maps, failure to lookup the value
         * means there is no entry for that key. Do not print an error message
         * in that case.
         */
        if ((map_is_map_of_maps(map_info->type) ||
             map_is_map_of_progs(map_info->type)) && lookup_errno == ENOENT)
                return;

        if (json_output) {
                jsonw_start_object(json_wtr);   /* entry */
                jsonw_name(json_wtr, "key");
                print_hex_data_json(key, map_info->key_size);
                jsonw_name(json_wtr, "value");
                jsonw_start_object(json_wtr);   /* error */
                jsonw_string_field(json_wtr, "error", strerror(lookup_errno));
                jsonw_end_object(json_wtr);     /* error */
                jsonw_end_object(json_wtr);     /* entry */
        } else {
                const char *msg = NULL;

                if (lookup_errno == ENOENT)
                        msg = "<no entry>";
                else if (lookup_errno == ENOSPC &&
                         map_info->type == BPF_MAP_TYPE_REUSEPORT_SOCKARRAY)
                        msg = "<cannot read>";

                print_entry_error_msg(map_info, key,
                                      msg ? : strerror(lookup_errno));
        }
}

static void print_entry_plain(struct bpf_map_info *info, unsigned char *key,
                              unsigned char *value)
{
        if (!map_is_per_cpu(info->type)) {
                bool single_line, break_names;

                break_names = info->key_size > 16 || info->value_size > 16;
                single_line = info->key_size + info->value_size <= 24 &&
                        !break_names;

                if (info->key_size) {
                        printf("key:%c", break_names ? '\n' : ' ');
                        fprint_hex(stdout, key, info->key_size, " ");

                        printf(single_line ? "  " : "\n");
                }

                if (info->value_size) {
                        if (map_is_map_of_maps(info->type)) {
                                printf("inner_map_id:%c", break_names ? '\n' : ' ');
                                printf("%u ", *(unsigned int *)value);
                        } else {
                                printf("value:%c", break_names ? '\n' : ' ');
                                fprint_hex(stdout, value, info->value_size, " ");
                        }
                }

                printf("\n");
        } else {
                unsigned int i, n, step;

                n = get_possible_cpus();
                step = round_up(info->value_size, 8);

                if (info->key_size) {
                        printf("key:\n");
                        fprint_hex(stdout, key, info->key_size, " ");
                        printf("\n");
                }
                if (info->value_size) {
                        for (i = 0; i < n; i++) {
                                printf("value (CPU %02u):%c",
                                       i, info->value_size > 16 ? '\n' : ' ');
                                fprint_hex(stdout, value + i * step,
                                           info->value_size, " ");
                                printf("\n");
                        }
                }
        }
}

static char **parse_bytes(char **argv, const char *name, unsigned char *val,
                          unsigned int n)
{
        unsigned int i = 0, base = 0;
        char *endptr;

        if (is_prefix(*argv, "hex")) {
                base = 16;
                argv++;
        }

        while (i < n && argv[i]) {
                val[i] = strtoul(argv[i], &endptr, base);
                if (*endptr) {
                        p_err("error parsing byte: %s", argv[i]);
                        return NULL;
                }
                i++;
        }

        if (i != n) {
                p_err("%s expected %u bytes got %u", name, n, i);
                return NULL;
        }

        return argv + i;
}

/* on per cpu maps we must copy the provided value on all value instances */
static void fill_per_cpu_value(struct bpf_map_info *info, void *value)
{
        unsigned int i, n, step;

        if (!map_is_per_cpu(info->type))
                return;

        n = get_possible_cpus();
        step = round_up(info->value_size, 8);
        for (i = 1; i < n; i++)
                memcpy(value + i * step, value, info->value_size);
}

static int parse_elem(char **argv, struct bpf_map_info *info, void *key,
                      void *value, __u32 key_size, __u32 value_size,
                      __u32 *flags, __u32 **value_fd, __u32 open_flags)
{
        if (!*argv) {
                if (!key && !value)
                        return 0;
                p_err("did not find %s", key ? "key" : "value");
                return -1;
        }

        if (is_prefix(*argv, "key")) {
                if (!key) {
                        if (key_size)
                                p_err("duplicate key");
                        else
                                p_err("unnecessary key");
                        return -1;
                }

                argv = parse_bytes(argv + 1, "key", key, key_size);
                if (!argv)
                        return -1;

                return parse_elem(argv, info, NULL, value, key_size, value_size,
                                  flags, value_fd, open_flags);
        } else if (is_prefix(*argv, "value")) {
                int fd;

                if (!value) {
                        if (value_size)
                                p_err("duplicate value");
                        else
                                p_err("unnecessary value");
                        return -1;
                }

                argv++;

                if (map_is_map_of_maps(info->type)) {
                        int argc = 2;

                        if (value_size != 4) {
                                p_err("value smaller than 4B for map in map?");
                                return -1;
                        }
                        if (!argv[0] || !argv[1]) {
                                p_err("not enough value arguments for map in map");
                                return -1;
                        }

                        fd = map_parse_fd(&argc, &argv, open_flags);
                        if (fd < 0)
                                return -1;

                        *value_fd = value;
                        **value_fd = fd;
                } else if (map_is_map_of_progs(info->type)) {
                        int argc = 2;

                        if (value_size != 4) {
                                p_err("value smaller than 4B for map of progs?");
                                return -1;
                        }
                        if (!argv[0] || !argv[1]) {
                                p_err("not enough value arguments for map of progs");
                                return -1;
                        }
                        if (is_prefix(*argv, "id"))
                                p_info("Warning: updating program array via MAP_ID, make sure this map is kept open\n"
                                       "         by some process or pinned otherwise update will be lost");

                        fd = prog_parse_fd(&argc, &argv);
                        if (fd < 0)
                                return -1;

                        *value_fd = value;
                        **value_fd = fd;
                } else {
                        argv = parse_bytes(argv, "value", value, value_size);
                        if (!argv)
                                return -1;

                        fill_per_cpu_value(info, value);
                }

                return parse_elem(argv, info, key, NULL, key_size, value_size,
                                  flags, NULL, open_flags);
        } else if (is_prefix(*argv, "any") || is_prefix(*argv, "noexist") ||
                   is_prefix(*argv, "exist")) {
                if (!flags) {
                        p_err("flags specified multiple times: %s", *argv);
                        return -1;
                }

                if (is_prefix(*argv, "any"))
                        *flags = BPF_ANY;
                else if (is_prefix(*argv, "noexist"))
                        *flags = BPF_NOEXIST;
                else if (is_prefix(*argv, "exist"))
                        *flags = BPF_EXIST;

                return parse_elem(argv + 1, info, key, value, key_size,
                                  value_size, NULL, value_fd, open_flags);
        }

        p_err("expected key or value, got: %s", *argv);
        return -1;
}

static void show_map_header_json(struct bpf_map_info *info, json_writer_t *wtr)
{
        const char *map_type_str;

        jsonw_uint_field(wtr, "id", info->id);
        map_type_str = libbpf_bpf_map_type_str(info->type);
        if (map_type_str)
                jsonw_string_field(wtr, "type", map_type_str);
        else
                jsonw_uint_field(wtr, "type", info->type);

        if (*info->name)
                jsonw_string_field(wtr, "name", info->name);

        jsonw_name(wtr, "flags");
        jsonw_printf(wtr, "%u", info->map_flags);
}

static int show_map_close_json(int fd, struct bpf_map_info *info)
{
        char *memlock, *frozen_str;
        int frozen = 0;

        memlock = get_fdinfo(fd, "memlock");
        frozen_str = get_fdinfo(fd, "frozen");

        jsonw_start_object(json_wtr);

        show_map_header_json(info, json_wtr);

        print_dev_json(info->ifindex, info->netns_dev, info->netns_ino);

        jsonw_uint_field(json_wtr, "bytes_key", info->key_size);
        jsonw_uint_field(json_wtr, "bytes_value", info->value_size);
        jsonw_uint_field(json_wtr, "max_entries", info->max_entries);

        if (memlock)
                jsonw_int_field(json_wtr, "bytes_memlock", atoll(memlock));
        free(memlock);

        if (info->type == BPF_MAP_TYPE_PROG_ARRAY) {
                char *owner_prog_type = get_fdinfo(fd, "owner_prog_type");
                char *owner_jited = get_fdinfo(fd, "owner_jited");

                if (owner_prog_type) {
                        unsigned int prog_type = atoi(owner_prog_type);
                        const char *prog_type_str;

                        prog_type_str = libbpf_bpf_prog_type_str(prog_type);
                        if (prog_type_str)
                                jsonw_string_field(json_wtr, "owner_prog_type",
                                                   prog_type_str);
                        else
                                jsonw_uint_field(json_wtr, "owner_prog_type",
                                                 prog_type);
                }
                if (owner_jited)
                        jsonw_bool_field(json_wtr, "owner_jited",
                                         !!atoi(owner_jited));

                free(owner_prog_type);
                free(owner_jited);
        }
        close(fd);

        if (frozen_str) {
                frozen = atoi(frozen_str);
                free(frozen_str);
        }
        jsonw_int_field(json_wtr, "frozen", frozen);

        if (info->btf_id)
                jsonw_int_field(json_wtr, "btf_id", info->btf_id);

        if (!hashmap__empty(map_table)) {
                struct hashmap_entry *entry;

                jsonw_name(json_wtr, "pinned");
                jsonw_start_array(json_wtr);
                hashmap__for_each_key_entry(map_table, entry, info->id)
                        jsonw_string(json_wtr, entry->pvalue);
                jsonw_end_array(json_wtr);
        }

        emit_obj_refs_json(refs_table, info->id, json_wtr);

        jsonw_end_object(json_wtr);

        return 0;
}

static void show_map_header_plain(struct bpf_map_info *info)
{
        const char *map_type_str;

        printf("%u: ", info->id);

        map_type_str = libbpf_bpf_map_type_str(info->type);
        if (map_type_str)
                printf("%s  ", map_type_str);
        else
                printf("type %u  ", info->type);

        if (*info->name)
                printf("name %s  ", info->name);

        printf("flags 0x%x", info->map_flags);
        print_dev_plain(info->ifindex, info->netns_dev, info->netns_ino);
        printf("\n");
}

static int show_map_close_plain(int fd, struct bpf_map_info *info)
{
        char *memlock, *frozen_str;
        int frozen = 0;

        memlock = get_fdinfo(fd, "memlock");
        frozen_str = get_fdinfo(fd, "frozen");

        show_map_header_plain(info);
        printf("\tkey %uB  value %uB  max_entries %u",
               info->key_size, info->value_size, info->max_entries);

        if (memlock)
                printf("  memlock %sB", memlock);
        free(memlock);

        if (info->type == BPF_MAP_TYPE_PROG_ARRAY) {
                char *owner_prog_type = get_fdinfo(fd, "owner_prog_type");
                char *owner_jited = get_fdinfo(fd, "owner_jited");

                if (owner_prog_type || owner_jited)
                        printf("\n\t");
                if (owner_prog_type) {
                        unsigned int prog_type = atoi(owner_prog_type);
                        const char *prog_type_str;

                        prog_type_str = libbpf_bpf_prog_type_str(prog_type);
                        if (prog_type_str)
                                printf("owner_prog_type %s  ", prog_type_str);
                        else
                                printf("owner_prog_type %u  ", prog_type);
                }
                if (owner_jited)
                        printf("owner%s jited",
                               atoi(owner_jited) ? "" : " not");

                free(owner_prog_type);
                free(owner_jited);
        }
        close(fd);

        if (!hashmap__empty(map_table)) {
                struct hashmap_entry *entry;

                hashmap__for_each_key_entry(map_table, entry, info->id)
                        printf("\n\tpinned %s", (char *)entry->pvalue);
        }

        if (frozen_str) {
                frozen = atoi(frozen_str);
                free(frozen_str);
        }

        if (info->btf_id || frozen)
                printf("\n\t");

        if (info->btf_id)
                printf("btf_id %u", info->btf_id);

        if (frozen)
                printf("%sfrozen", info->btf_id ? "  " : "");

        emit_obj_refs_plain(refs_table, info->id, "\n\tpids ");

        printf("\n");
        return 0;
}

static int do_show_subset(int argc, char **argv)
{
        struct bpf_map_info info = {};
        __u32 len = sizeof(info);
        int *fds = NULL;
        int nb_fds, i;
        int err = -1;

        fds = malloc(sizeof(int));
        if (!fds) {
                p_err("mem alloc failed");
                return -1;
        }
        nb_fds = map_parse_fds(&argc, &argv, &fds, BPF_F_RDONLY);
        if (nb_fds < 1)
                goto exit_free;

        if (json_output && nb_fds > 1)
                jsonw_start_array(json_wtr);    /* root array */
        for (i = 0; i < nb_fds; i++) {
                err = bpf_map_get_info_by_fd(fds[i], &info, &len);
                if (err) {
                        p_err("can't get map info: %s",
                              strerror(errno));
                        for (; i < nb_fds; i++)
                                close(fds[i]);
                        break;
                }

                if (json_output)
                        show_map_close_json(fds[i], &info);
                else
                        show_map_close_plain(fds[i], &info);

                close(fds[i]);
        }
        if (json_output && nb_fds > 1)
                jsonw_end_array(json_wtr);      /* root array */

exit_free:
        free(fds);
        return err;
}

static int do_show(int argc, char **argv)
{
        LIBBPF_OPTS(bpf_get_fd_by_id_opts, opts);
        struct bpf_map_info info = {};
        __u32 len = sizeof(info);
        __u32 id = 0;
        int err;
        int fd;

        opts.open_flags = BPF_F_RDONLY;

        if (show_pinned) {
                map_table = hashmap__new(hash_fn_for_key_as_id,
                                         equal_fn_for_key_as_id, NULL);
                if (IS_ERR(map_table)) {
                        p_err("failed to create hashmap for pinned paths");
                        return -1;
                }
                build_pinned_obj_table(map_table, BPF_OBJ_MAP);
        }
        build_obj_refs_table(&refs_table, BPF_OBJ_MAP);

        if (argc == 2)
                return do_show_subset(argc, argv);

        if (argc)
                return BAD_ARG();

        if (json_output)
                jsonw_start_array(json_wtr);
        while (true) {
                err = bpf_map_get_next_id(id, &id);
                if (err) {
                        if (errno == ENOENT)
                                break;
                        p_err("can't get next map: %s%s", strerror(errno),
                              errno == EINVAL ? " -- kernel too old?" : "");
                        break;
                }

                fd = bpf_map_get_fd_by_id_opts(id, &opts);
                if (fd < 0) {
                        if (errno == ENOENT)
                                continue;
                        p_err("can't get map by id (%u): %s",
                              id, strerror(errno));
                        break;
                }

                err = bpf_map_get_info_by_fd(fd, &info, &len);
                if (err) {
                        p_err("can't get map info: %s", strerror(errno));
                        close(fd);
                        break;
                }

                if (json_output)
                        show_map_close_json(fd, &info);
                else
                        show_map_close_plain(fd, &info);
        }
        if (json_output)
                jsonw_end_array(json_wtr);

        delete_obj_refs_table(refs_table);

        if (show_pinned)
                delete_pinned_obj_table(map_table);

        return errno == ENOENT ? 0 : -1;
}

static int dump_map_elem(int fd, void *key, void *value,
                         struct bpf_map_info *map_info, struct btf *btf,
                         json_writer_t *btf_wtr)
{
        if (bpf_map_lookup_elem(fd, key, value)) {
                print_entry_error(map_info, key, errno);
                return -1;
        }

        if (json_output) {
                print_entry_json(map_info, key, value, btf);
        } else if (btf) {
                struct btf_dumper d = {
                        .btf = btf,
                        .jw = btf_wtr,
                        .is_plain_text = true,
                };

                do_dump_btf(&d, map_info, key, value);
        } else {
                print_entry_plain(map_info, key, value);
        }

        return 0;
}

static int maps_have_btf(int *fds, int nb_fds)
{
        struct bpf_map_info info = {};
        __u32 len = sizeof(info);
        int err, i;

        for (i = 0; i < nb_fds; i++) {
                err = bpf_map_get_info_by_fd(fds[i], &info, &len);
                if (err) {
                        p_err("can't get map info: %s", strerror(errno));
                        return -1;
                }

                if (!info.btf_id)
                        return 0;
        }

        return 1;
}

static struct btf *btf_vmlinux;

static int get_map_kv_btf(const struct bpf_map_info *info, struct btf **btf)
{
        int err = 0;

        if (info->btf_vmlinux_value_type_id) {
                if (!btf_vmlinux) {
                        btf_vmlinux = libbpf_find_kernel_btf();
                        if (!btf_vmlinux) {
                                p_err("failed to get kernel btf");
                                return -errno;
                        }
                }
                *btf = btf_vmlinux;
        } else if (info->btf_value_type_id) {
                *btf = btf__load_from_kernel_by_id(info->btf_id);
                if (!*btf) {
                        err = -errno;
                        p_err("failed to get btf");
                }
        } else {
                *btf = NULL;
        }

        return err;
}

static void free_map_kv_btf(struct btf *btf)
{
        if (btf != btf_vmlinux)
                btf__free(btf);
}

static int
map_dump(int fd, struct bpf_map_info *info, json_writer_t *wtr,
         bool show_header)
{
        void *key, *value, *prev_key;
        unsigned int num_elems = 0;
        struct btf *btf = NULL;
        int err;

        key = malloc(info->key_size);
        value = alloc_value(info);
        if (!key || !value) {
                p_err("mem alloc failed");
                err = -1;
                goto exit_free;
        }

        prev_key = NULL;

        if (wtr) {
                err = get_map_kv_btf(info, &btf);
                if (err) {
                        goto exit_free;
                }

                if (show_header) {
                        jsonw_start_object(wtr);        /* map object */
                        show_map_header_json(info, wtr);
                        jsonw_name(wtr, "elements");
                }
                jsonw_start_array(wtr);         /* elements */
        } else if (show_header) {
                show_map_header_plain(info);
        }

        if (info->type == BPF_MAP_TYPE_REUSEPORT_SOCKARRAY &&
            info->value_size != 8) {
                const char *map_type_str;

                map_type_str = libbpf_bpf_map_type_str(info->type);
                p_info("Warning: cannot read values from %s map with value_size != 8",
                       map_type_str);
        }
        while (true) {
                err = bpf_map_get_next_key(fd, prev_key, key);
                if (err) {
                        if (errno == ENOENT)
                                err = 0;
                        break;
                }
                if (!dump_map_elem(fd, key, value, info, btf, wtr))
                        num_elems++;
                prev_key = key;
        }

        if (wtr) {
                jsonw_end_array(wtr);   /* elements */
                if (show_header)
                        jsonw_end_object(wtr);  /* map object */
        } else {
                printf("Found %u element%s\n", num_elems,
                       num_elems != 1 ? "s" : "");
        }

exit_free:
        free(key);
        free(value);
        close(fd);
        free_map_kv_btf(btf);

        return err;
}

static int do_dump(int argc, char **argv)
{
        json_writer_t *wtr = NULL, *btf_wtr = NULL;
        struct bpf_map_info info = {};
        int nb_fds, i = 0;
        __u32 len = sizeof(info);
        int *fds = NULL;
        int err = -1;

        if (argc != 2)
                usage();

        fds = malloc(sizeof(int));
        if (!fds) {
                p_err("mem alloc failed");
                return -1;
        }
        nb_fds = map_parse_fds(&argc, &argv, &fds, BPF_F_RDONLY);
        if (nb_fds < 1)
                goto exit_free;

        if (json_output) {
                wtr = json_wtr;
        } else {
                int do_plain_btf;

                do_plain_btf = maps_have_btf(fds, nb_fds);
                if (do_plain_btf < 0)
                        goto exit_close;

                if (do_plain_btf) {
                        btf_wtr = get_btf_writer();
                        wtr = btf_wtr;
                        if (!btf_wtr)
                                p_info("failed to create json writer for btf. falling back to plain output");
                }
        }

        if (wtr && nb_fds > 1)
                jsonw_start_array(wtr); /* root array */
        for (i = 0; i < nb_fds; i++) {
                if (bpf_map_get_info_by_fd(fds[i], &info, &len)) {
                        p_err("can't get map info: %s", strerror(errno));
                        break;
                }
                err = map_dump(fds[i], &info, wtr, nb_fds > 1);
                if (!wtr && i != nb_fds - 1)
                        printf("\n");

                if (err)
                        break;
                close(fds[i]);
        }
        if (wtr && nb_fds > 1)
                jsonw_end_array(wtr);   /* root array */

        if (btf_wtr)
                jsonw_destroy(&btf_wtr);
exit_close:
        for (; i < nb_fds; i++)
                close(fds[i]);
exit_free:
        free(fds);
        btf__free(btf_vmlinux);
        return err;
}

static int alloc_key_value(struct bpf_map_info *info, void **key, void **value)
{
        *key = NULL;
        *value = NULL;

        if (info->key_size) {
                *key = malloc(info->key_size);
                if (!*key) {
                        p_err("key mem alloc failed");
                        return -1;
                }
        }

        if (info->value_size) {
                *value = alloc_value(info);
                if (!*value) {
                        p_err("value mem alloc failed");
                        free(*key);
                        *key = NULL;
                        return -1;
                }
        }

        return 0;
}

static int do_update(int argc, char **argv)
{
        struct bpf_map_info info = {};
        __u32 len = sizeof(info);
        __u32 *value_fd = NULL;
        __u32 flags = BPF_ANY;
        void *key, *value;
        int fd, err;

        if (argc < 2)
                usage();

        fd = map_parse_fd_and_info(&argc, &argv, &info, &len, 0);
        if (fd < 0)
                return -1;

        err = alloc_key_value(&info, &key, &value);
        if (err)
                goto exit_free;

        err = parse_elem(argv, &info, key, value, info.key_size,
                         info.value_size, &flags, &value_fd, 0);
        if (err)
                goto exit_free;

        err = bpf_map_update_elem(fd, key, value, flags);
        if (err) {
                p_err("update failed: %s", strerror(errno));
                goto exit_free;
        }

exit_free:
        if (value_fd)
                close(*value_fd);
        free(key);
        free(value);
        close(fd);

        if (!err && json_output)
                jsonw_null(json_wtr);
        return err;
}

static void print_key_value(struct bpf_map_info *info, void *key,
                            void *value)
{
        json_writer_t *btf_wtr;
        struct btf *btf;

        if (get_map_kv_btf(info, &btf))
                return;

        if (json_output) {
                print_entry_json(info, key, value, btf);
        } else if (btf) {
                /* if here json_wtr wouldn't have been initialised,
                 * so let's create separate writer for btf
                 */
                btf_wtr = get_btf_writer();
                if (!btf_wtr) {
                        p_info("failed to create json writer for btf. falling back to plain output");
                        btf__free(btf);
                        btf = NULL;
                        print_entry_plain(info, key, value);
                } else {
                        struct btf_dumper d = {
                                .btf = btf,
                                .jw = btf_wtr,
                                .is_plain_text = true,
                        };

                        do_dump_btf(&d, info, key, value);
                        jsonw_destroy(&btf_wtr);
                }
        } else {
                print_entry_plain(info, key, value);
        }
        btf__free(btf);
}

static int do_lookup(int argc, char **argv)
{
        struct bpf_map_info info = {};
        __u32 len = sizeof(info);
        void *key, *value;
        int err;
        int fd;

        if (argc < 2)
                usage();

        fd = map_parse_fd_and_info(&argc, &argv, &info, &len, BPF_F_RDONLY);
        if (fd < 0)
                return -1;

        err = alloc_key_value(&info, &key, &value);
        if (err)
                goto exit_free;

        err = parse_elem(argv, &info, key, NULL, info.key_size, 0, NULL, NULL,
                         BPF_F_RDONLY);
        if (err)
                goto exit_free;

        err = bpf_map_lookup_elem(fd, key, value);
        if (err) {
                if (errno == ENOENT) {
                        if (json_output) {
                                jsonw_null(json_wtr);
                        } else {
                                printf("key:\n");
                                fprint_hex(stdout, key, info.key_size, " ");
                                printf("\n\nNot found\n");
                        }
                } else {
                        p_err("lookup failed: %s", strerror(errno));
                }

                goto exit_free;
        }

        /* here means bpf_map_lookup_elem() succeeded */
        print_key_value(&info, key, value);

exit_free:
        free(key);
        free(value);
        close(fd);

        return err;
}

static int do_getnext(int argc, char **argv)
{
        struct bpf_map_info info = {};
        __u32 len = sizeof(info);
        void *key, *nextkey;
        int err;
        int fd;

        if (argc < 2)
                usage();

        fd = map_parse_fd_and_info(&argc, &argv, &info, &len, BPF_F_RDONLY);
        if (fd < 0)
                return -1;

        key = malloc(info.key_size);
        nextkey = malloc(info.key_size);
        if (!key || !nextkey) {
                p_err("mem alloc failed");
                err = -1;
                goto exit_free;
        }

        if (argc) {
                err = parse_elem(argv, &info, key, NULL, info.key_size, 0, NULL,
                                 NULL, BPF_F_RDONLY);
                if (err)
                        goto exit_free;
        } else {
                free(key);
                key = NULL;
        }

        err = bpf_map_get_next_key(fd, key, nextkey);
        if (err) {
                p_err("can't get next key: %s", strerror(errno));
                goto exit_free;
        }

        if (json_output) {
                jsonw_start_object(json_wtr);
                if (key) {
                        jsonw_name(json_wtr, "key");
                        print_hex_data_json(key, info.key_size);
                } else {
                        jsonw_null_field(json_wtr, "key");
                }
                jsonw_name(json_wtr, "next_key");
                print_hex_data_json(nextkey, info.key_size);
                jsonw_end_object(json_wtr);
        } else {
                if (key) {
                        printf("key:\n");
                        fprint_hex(stdout, key, info.key_size, " ");
                        printf("\n");
                } else {
                        printf("key: None\n");
                }
                printf("next key:\n");
                fprint_hex(stdout, nextkey, info.key_size, " ");
                printf("\n");
        }

exit_free:
        free(nextkey);
        free(key);
        close(fd);

        return err;
}

static int do_delete(int argc, char **argv)
{
        struct bpf_map_info info = {};
        __u32 len = sizeof(info);
        void *key;
        int err;
        int fd;

        if (argc < 2)
                usage();

        fd = map_parse_fd_and_info(&argc, &argv, &info, &len, 0);
        if (fd < 0)
                return -1;

        key = malloc(info.key_size);
        if (!key) {
                p_err("mem alloc failed");
                err = -1;
                goto exit_free;
        }

        err = parse_elem(argv, &info, key, NULL, info.key_size, 0, NULL, NULL,
                         0);
        if (err)
                goto exit_free;

        err = bpf_map_delete_elem(fd, key);
        if (err)
                p_err("delete failed: %s", strerror(errno));

exit_free:
        free(key);
        close(fd);

        if (!err && json_output)
                jsonw_null(json_wtr);
        return err;
}

static int map_parse_read_only_fd(int *argc, char ***argv)
{
        return map_parse_fd(argc, argv, BPF_F_RDONLY);
}

static int do_pin(int argc, char **argv)
{
        int err;

        err = do_pin_any(argc, argv, map_parse_read_only_fd);
        if (!err && json_output)
                jsonw_null(json_wtr);
        return err;
}

static int do_create(int argc, char **argv)
{
        LIBBPF_OPTS(bpf_map_create_opts, attr);
        enum bpf_map_type map_type = BPF_MAP_TYPE_UNSPEC;
        __u32 key_size = 0, value_size = 0, max_entries = 0;
        const char *map_name = NULL;
        const char *pinfile;
        int err = -1, fd;

        if (!REQ_ARGS(7))
                return -1;
        pinfile = GET_ARG();

        while (argc) {
                if (!REQ_ARGS(2))
                        return -1;

                if (is_prefix(*argv, "type")) {
                        NEXT_ARG();

                        if (map_type) {
                                p_err("map type already specified");
                                goto exit;
                        }

                        map_type = map_type_from_str(*argv);
                        if ((int)map_type < 0) {
                                p_err("unrecognized map type: %s", *argv);
                                goto exit;
                        }
                        NEXT_ARG();
                } else if (is_prefix(*argv, "name")) {
                        NEXT_ARG();
                        map_name = GET_ARG();
                        if (strlen(map_name) > BPF_OBJ_NAME_LEN - 1) {
                                p_info("Warning: map name is longer than %u characters, it will be truncated.",
                                      BPF_OBJ_NAME_LEN - 1);
                        }
                } else if (is_prefix(*argv, "key")) {
                        if (parse_u32_arg(&argc, &argv, &key_size,
                                          "key size"))
                                goto exit;
                } else if (is_prefix(*argv, "value")) {
                        if (parse_u32_arg(&argc, &argv, &value_size,
                                          "value size"))
                                goto exit;
                } else if (is_prefix(*argv, "entries")) {
                        if (parse_u32_arg(&argc, &argv, &max_entries,
                                          "max entries"))
                                goto exit;
                } else if (is_prefix(*argv, "flags")) {
                        if (parse_u32_arg(&argc, &argv, &attr.map_flags,
                                          "flags"))
                                goto exit;
                } else if (is_prefix(*argv, "dev")) {
                        p_info("Warning: 'bpftool map create [...] dev <ifname>' syntax is deprecated.\n"
                               "Going further, please use 'offload_dev <ifname>' to request hardware offload for the map.");
                        goto offload_dev;
                } else if (is_prefix(*argv, "offload_dev")) {
offload_dev:
                        NEXT_ARG();

                        if (attr.map_ifindex) {
                                p_err("offload device already specified");
                                goto exit;
                        }

                        attr.map_ifindex = if_nametoindex(*argv);
                        if (!attr.map_ifindex) {
                                p_err("unrecognized netdevice '%s': %s",
                                      *argv, strerror(errno));
                                goto exit;
                        }
                        NEXT_ARG();
                } else if (is_prefix(*argv, "inner_map")) {
                        struct bpf_map_info info = {};
                        __u32 len = sizeof(info);
                        int inner_map_fd;

                        NEXT_ARG();
                        if (!REQ_ARGS(2))
                                usage();
                        inner_map_fd = map_parse_fd_and_info(&argc, &argv,
                                                             &info, &len, BPF_F_RDONLY);
                        if (inner_map_fd < 0)
                                return -1;
                        attr.inner_map_fd = inner_map_fd;
                } else {
                        p_err("unknown arg %s", *argv);
                        goto exit;
                }
        }

        if (!map_name) {
                p_err("map name not specified");
                goto exit;
        }

        set_max_rlimit();

        fd = bpf_map_create(map_type, map_name, key_size, value_size, max_entries, &attr);
        if (fd < 0) {
                p_err("map create failed: %s", strerror(errno));
                goto exit;
        }

        err = do_pin_fd(fd, pinfile);
        close(fd);
        if (err)
                goto exit;

        if (json_output)
                jsonw_null(json_wtr);

exit:
        if (attr.inner_map_fd > 0)
                close(attr.inner_map_fd);

        return err;
}

static int do_pop_dequeue(int argc, char **argv)
{
        struct bpf_map_info info = {};
        __u32 len = sizeof(info);
        void *key, *value;
        int err;
        int fd;

        if (argc < 2)
                usage();

        fd = map_parse_fd_and_info(&argc, &argv, &info, &len, 0);
        if (fd < 0)
                return -1;

        err = alloc_key_value(&info, &key, &value);
        if (err)
                goto exit_free;

        err = bpf_map_lookup_and_delete_elem(fd, key, value);
        if (err) {
                if (errno == ENOENT) {
                        if (json_output)
                                jsonw_null(json_wtr);
                        else
                                printf("Error: empty map\n");
                } else {
                        p_err("pop failed: %s", strerror(errno));
                }

                goto exit_free;
        }

        print_key_value(&info, key, value);

exit_free:
        free(key);
        free(value);
        close(fd);

        return err;
}

static int do_freeze(int argc, char **argv)
{
        int err, fd;

        if (!REQ_ARGS(2))
                return -1;

        fd = map_parse_fd(&argc, &argv, 0);
        if (fd < 0)
                return -1;

        if (argc) {
                close(fd);
                return BAD_ARG();
        }

        err = bpf_map_freeze(fd);
        close(fd);
        if (err) {
                p_err("failed to freeze map: %s", strerror(errno));
                return err;
        }

        if (json_output)
                jsonw_null(json_wtr);

        return 0;
}

static int do_help(int argc, char **argv)
{
        if (json_output) {
                jsonw_null(json_wtr);
                return 0;
        }

        fprintf(stderr,
                "Usage: %1$s %2$s { show | list }   [MAP]\n"
                "       %1$s %2$s create     FILE type TYPE key KEY_SIZE value VALUE_SIZE \\\n"
                "                                  entries MAX_ENTRIES name NAME [flags FLAGS] \\\n"
                "                                  [inner_map MAP] [offload_dev NAME]\n"
                "       %1$s %2$s dump       MAP\n"
                "       %1$s %2$s update     MAP [key DATA] [value VALUE] [UPDATE_FLAGS]\n"
                "       %1$s %2$s lookup     MAP [key DATA]\n"
                "       %1$s %2$s getnext    MAP [key DATA]\n"
                "       %1$s %2$s delete     MAP  key DATA\n"
                "       %1$s %2$s pin        MAP  FILE\n"
                "       %1$s %2$s event_pipe MAP [cpu N index M]\n"
                "       %1$s %2$s peek       MAP\n"
                "       %1$s %2$s push       MAP value VALUE\n"
                "       %1$s %2$s pop        MAP\n"
                "       %1$s %2$s enqueue    MAP value VALUE\n"
                "       %1$s %2$s dequeue    MAP\n"
                "       %1$s %2$s freeze     MAP\n"
                "       %1$s %2$s help\n"
                "\n"
                "       " HELP_SPEC_MAP "\n"
                "       DATA := { [hex] BYTES }\n"
                "       " HELP_SPEC_PROGRAM "\n"
                "       VALUE := { DATA | MAP | PROG }\n"
                "       UPDATE_FLAGS := { any | exist | noexist }\n"
                "       TYPE := { hash | array | prog_array | perf_event_array | percpu_hash |\n"
                "                 percpu_array | stack_trace | cgroup_array | lru_hash |\n"
                "                 lru_percpu_hash | lpm_trie | array_of_maps | hash_of_maps |\n"
                "                 devmap | devmap_hash | sockmap | cpumap | xskmap | sockhash |\n"
                "                 cgroup_storage | reuseport_sockarray | percpu_cgroup_storage |\n"
                "                 queue | stack | sk_storage | struct_ops | ringbuf | inode_storage |\n"
                "                 task_storage | bloom_filter | user_ringbuf | cgrp_storage | arena |\n"
                "                 insn_array }\n"
                "       " HELP_SPEC_OPTIONS " |\n"
                "                    {-f|--bpffs} | {-n|--nomount} }\n"
                "",
                bin_name, argv[-2]);

        return 0;
}

static const struct cmd cmds[] = {
        { "show",       do_show },
        { "list",       do_show },
        { "help",       do_help },
        { "dump",       do_dump },
        { "update",     do_update },
        { "lookup",     do_lookup },
        { "getnext",    do_getnext },
        { "delete",     do_delete },
        { "pin",        do_pin },
        { "event_pipe", do_event_pipe },
        { "create",     do_create },
        { "peek",       do_lookup },
        { "push",       do_update },
        { "enqueue",    do_update },
        { "pop",        do_pop_dequeue },
        { "dequeue",    do_pop_dequeue },
        { "freeze",     do_freeze },
        { 0 }
};

int do_map(int argc, char **argv)
{
        return cmd_select(cmds, argc, argv, do_help);
}