Add `bpftool token show` command to get token info from bpffs in /proc/mounts. Example plain output for `token show`: token_info /sys/fs/bpf/token allowed_cmds: map_create prog_load allowed_maps: allowed_progs: kprobe allowed_attachs: xdp token_info /sys/fs/bpf/token2 allowed_cmds: map_create prog_load allowed_maps: allowed_progs: kprobe allowed_attachs: xdp Example json output for `token show`: [{ "token_info": "/sys/fs/bpf/token", "allowed_cmds": ["map_create", "prog_load"], "allowed_maps": [], "allowed_progs": ["kprobe"], "allowed_attachs": ["xdp"] }, { "token_info": "/sys/fs/bpf/token2", "allowed_cmds": ["map_create", "prog_load"], "allowed_maps": [], "allowed_progs": ["kprobe"], "allowed_attachs": ["xdp"] }] Signed-off-by: Tao Chen --- tools/bpf/bpftool/main.c | 3 +- tools/bpf/bpftool/main.h | 1 + tools/bpf/bpftool/token.c | 232 ++++++++++++++++++++++++++++++++++++++ 3 files changed, 235 insertions(+), 1 deletion(-) create mode 100644 tools/bpf/bpftool/token.c Change list: v1 -> v2: Quentin suggested: - patch1 - remove zclose macro. - rename __json_array_str to split_json_array_str - print empty array when value is null for json format. - show all tokens info and format plain output for readable. - add info when token not found. - add copyright in token.c - patch2 - update 'eBPF progs' to 'eBPF tokens'. - update description. - patch3 - add bash-completion. v1: https://lore.kernel.org/bpf/20250720173310.1334483-1-chen.dylane@linux.dev diff --git a/tools/bpf/bpftool/main.c b/tools/bpf/bpftool/main.c index 2b7f2bd3a7d..0f1183b2ed0 100644 --- a/tools/bpf/bpftool/main.c +++ b/tools/bpf/bpftool/main.c @@ -61,7 +61,7 @@ static int do_help(int argc, char **argv) " %s batch file FILE\n" " %s version\n" "\n" - " OBJECT := { prog | map | link | cgroup | perf | net | feature | btf | gen | struct_ops | iter }\n" + " OBJECT := { prog | map | link | cgroup | perf | net | feature | btf | gen | struct_ops | iter | token }\n" " " HELP_SPEC_OPTIONS " |\n" " {-V|--version} }\n" "", @@ -87,6 +87,7 @@ static const struct cmd commands[] = { { "gen", do_gen }, { "struct_ops", do_struct_ops }, { "iter", do_iter }, + { "token", do_token }, { "version", do_version }, { 0 } }; diff --git a/tools/bpf/bpftool/main.h b/tools/bpf/bpftool/main.h index 6db704fda5c..a2bb0714b3d 100644 --- a/tools/bpf/bpftool/main.h +++ b/tools/bpf/bpftool/main.h @@ -166,6 +166,7 @@ int do_tracelog(int argc, char **arg) __weak; int do_feature(int argc, char **argv) __weak; int do_struct_ops(int argc, char **argv) __weak; int do_iter(int argc, char **argv) __weak; +int do_token(int argc, char **argv) __weak; int parse_u32_arg(int *argc, char ***argv, __u32 *val, const char *what); int prog_parse_fd(int *argc, char ***argv); diff --git a/tools/bpf/bpftool/token.c b/tools/bpf/bpftool/token.c new file mode 100644 index 00000000000..f72a116f9c6 --- /dev/null +++ b/tools/bpf/bpftool/token.c @@ -0,0 +1,232 @@ +// SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) +/* Copyright (C) 2025 Didi Technology Co., Tao Chen */ + +#ifndef _GNU_SOURCE +#define _GNU_SOURCE +#endif +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include "json_writer.h" +#include "main.h" + +#define MOUNTS_FILE "/proc/mounts" + +static bool has_delegate_options(const char *mnt_ops) +{ + return strstr(mnt_ops, "delegate_cmds") != NULL || + strstr(mnt_ops, "delegate_maps") != NULL || + strstr(mnt_ops, "delegate_progs") != NULL || + strstr(mnt_ops, "delegate_attachs") != NULL; +} + +static char *get_delegate_value(const char *opts, const char *key) +{ + char *token, *rest, *ret = NULL; + char *opts_copy = strdup(opts); + + if (!opts_copy) + return NULL; + + for (token = strtok_r(opts_copy, ",", &rest); token != NULL; + token = strtok_r(NULL, ",", &rest)) { + if (strncmp(token, key, strlen(key)) == 0 && + token[strlen(key)] == '=') { + ret = token + strlen(key) + 1; + break; + } + } + free(opts_copy); + + return ret; +} + +static void print_items_per_line(const char *input, int items_per_line) +{ + char *str, *rest, *strs; + int cnt = 0; + + if (!input) + return; + + strs = strdup(input); + if (!strs) + return; + + for (str = strtok_r(strs, ":", &rest); str != NULL; + str = strtok_r(NULL, ":", &rest)) { + if (cnt % items_per_line == 0) + printf("\n\t "); + + printf("%-20s", str); + cnt++; + } + + free(strs); +} + +#define ITEMS_PER_LINE 4 +static void show_token_info_plain(struct mntent *mntent) +{ + char *value; + + printf("token_info %s", mntent->mnt_dir); + + printf("\n\tallowed_cmds:"); + value = get_delegate_value(mntent->mnt_opts, "delegate_cmds"); + print_items_per_line(value, ITEMS_PER_LINE); + + printf("\n\tallowed_maps:"); + value = get_delegate_value(mntent->mnt_opts, "delegate_maps"); + print_items_per_line(value, ITEMS_PER_LINE); + + printf("\n\tallowed_progs:"); + value = get_delegate_value(mntent->mnt_opts, "delegate_progs"); + print_items_per_line(value, ITEMS_PER_LINE); + + printf("\n\tallowed_attachs:"); + value = get_delegate_value(mntent->mnt_opts, "delegate_attachs"); + print_items_per_line(value, ITEMS_PER_LINE); + printf("\n"); +} + +static void split_json_array_str(const char *input) +{ + char *str, *rest, *strs; + + if (!input) { + jsonw_start_array(json_wtr); + jsonw_end_array(json_wtr); + return; + } + + strs = strdup(input); + if (!strs) + return; + + jsonw_start_array(json_wtr); + for (str = strtok_r(strs, ":", &rest); str != NULL; + str = strtok_r(NULL, ":", &rest)) { + jsonw_string(json_wtr, str); + } + jsonw_end_array(json_wtr); + + free(strs); +} + +static void show_token_info_json(struct mntent *mntent) +{ + char *value; + + jsonw_start_object(json_wtr); + + jsonw_string_field(json_wtr, "token_info", mntent->mnt_dir); + + jsonw_name(json_wtr, "allowed_cmds"); + value = get_delegate_value(mntent->mnt_opts, "delegate_cmds"); + split_json_array_str(value); + + jsonw_name(json_wtr, "allowed_maps"); + value = get_delegate_value(mntent->mnt_opts, "delegate_maps"); + split_json_array_str(value); + + jsonw_name(json_wtr, "allowed_progs"); + value = get_delegate_value(mntent->mnt_opts, "delegate_progs"); + split_json_array_str(value); + + jsonw_name(json_wtr, "allowed_attachs"); + value = get_delegate_value(mntent->mnt_opts, "delegate_attachs"); + split_json_array_str(value); + + jsonw_end_object(json_wtr); +} + +static int __show_token_info(struct mntent *mntent) +{ + + if (json_output) + show_token_info_json(mntent); + else + show_token_info_plain(mntent); + + return 0; +} + +static int show_token_info(void) +{ + FILE *fp; + struct mntent *ent; + bool hit = false; + + fp = setmntent(MOUNTS_FILE, "r"); + if (!fp) { + p_err("Failed to open: %s", MOUNTS_FILE); + return -1; + } + + if (json_output) + jsonw_start_array(json_wtr); + + while ((ent = getmntent(fp)) != NULL) { + if (strncmp(ent->mnt_type, "bpf", 3) == 0) { + if (has_delegate_options(ent->mnt_opts)) { + __show_token_info(ent); + hit = true; + } + } + } + + if (json_output) + jsonw_end_array(json_wtr); + + if (!hit) + p_info("Token info not found"); + + endmntent(fp); + + return 0; +} + +static int do_show(int argc, char **argv) +{ + if (argc) + return BAD_ARG(); + + return show_token_info(); +} + +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 }\n" + " %1$s %2$s help\n" + "\n" + "", + bin_name, argv[-2]); + return 0; +} + +static const struct cmd cmds[] = { + { "show", do_show }, + { "list", do_show }, + { "help", do_help }, + { 0 } +}; + +int do_token(int argc, char **argv) +{ + return cmd_select(cmds, argc, argv, do_help); +} -- 2.48.1