android_kernel_xiaomi_sm7250/tools/bpf/bpftool/main.h
Quentin Monnet ee7d247381 tools: bpftool: pass an argument to silence open_obj_pinned()
[ Upstream commit f120919f9905a2cad9dea792a28a11fb623f72c1 ]

Function open_obj_pinned() prints error messages when it fails to open a
link in the BPF virtual file system. However, in some occasions it is
not desirable to print an error, for example when we parse all links
under the bpffs root, and the error is due to some paths actually being
symbolic links.

Example output:

    # ls -l /sys/fs/bpf/
    lrwxrwxrwx 1 root root 0 Oct 18 19:00 ip -> /sys/fs/bpf/tc/
    drwx------ 3 root root 0 Oct 18 19:00 tc
    lrwxrwxrwx 1 root root 0 Oct 18 19:00 xdp -> /sys/fs/bpf/tc/

    # bpftool --bpffs prog show
    Error: bpf obj get (/sys/fs/bpf): Permission denied
    Error: bpf obj get (/sys/fs/bpf): Permission denied

    # strace -e bpf bpftool --bpffs prog show
    bpf(BPF_OBJ_GET, {pathname="/sys/fs/bpf/ip", bpf_fd=0}, 72) = -1 EACCES (Permission denied)
    Error: bpf obj get (/sys/fs/bpf): Permission denied
    bpf(BPF_OBJ_GET, {pathname="/sys/fs/bpf/xdp", bpf_fd=0}, 72) = -1 EACCES (Permission denied)
    Error: bpf obj get (/sys/fs/bpf): Permission denied
    ...

To fix it, pass a bool as a second argument to the function, and prevent
it from printing an error when the argument is set to true.

Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-12-01 09:17:31 +01:00

169 lines
5.3 KiB
C

/*
* Copyright (C) 2017-2018 Netronome Systems, Inc.
*
* This software is dual licensed under the GNU General License Version 2,
* June 1991 as shown in the file COPYING in the top-level directory of this
* source tree or the BSD 2-Clause License provided below. You have the
* option to license this software under the complete terms of either license.
*
* The BSD 2-Clause License:
*
* Redistribution and use in source and binary forms, with or
* without modification, are permitted provided that the following
* conditions are met:
*
* 1. Redistributions of source code must retain the above
* copyright notice, this list of conditions and the following
* disclaimer.
*
* 2. Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following
* disclaimer in the documentation and/or other materials
* provided with the distribution.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
* BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
* ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*/
#ifndef __BPF_TOOL_H
#define __BPF_TOOL_H
/* BFD and kernel.h both define GCC_VERSION, differently */
#undef GCC_VERSION
#include <stdbool.h>
#include <stdio.h>
#include <linux/bpf.h>
#include <linux/compiler.h>
#include <linux/kernel.h>
#include <linux/hashtable.h>
#include <tools/libc_compat.h>
#include "json_writer.h"
#define ptr_to_u64(ptr) ((__u64)(unsigned long)(ptr))
#define NEXT_ARG() ({ argc--; argv++; if (argc < 0) usage(); })
#define NEXT_ARGP() ({ (*argc)--; (*argv)++; if (*argc < 0) usage(); })
#define BAD_ARG() ({ p_err("what is '%s'?", *argv); -1; })
#define GET_ARG() ({ argc--; *argv++; })
#define REQ_ARGS(cnt) \
({ \
int _cnt = (cnt); \
bool _res; \
\
if (argc < _cnt) { \
p_err("'%s' needs at least %d arguments, %d found", \
argv[-1], _cnt, argc); \
_res = false; \
} else { \
_res = true; \
} \
_res; \
})
#define ERR_MAX_LEN 1024
#define BPF_TAG_FMT "%02hhx%02hhx%02hhx%02hhx%02hhx%02hhx%02hhx%02hhx"
#define HELP_SPEC_PROGRAM \
"PROG := { id PROG_ID | pinned FILE | tag PROG_TAG }"
#define HELP_SPEC_OPTIONS \
"OPTIONS := { {-j|--json} [{-p|--pretty}] | {-f|--bpffs} }"
#define HELP_SPEC_MAP \
"MAP := { id MAP_ID | pinned FILE }"
enum bpf_obj_type {
BPF_OBJ_UNKNOWN,
BPF_OBJ_PROG,
BPF_OBJ_MAP,
};
extern const char *bin_name;
extern json_writer_t *json_wtr;
extern bool json_output;
extern bool show_pinned;
extern struct pinned_obj_table prog_table;
extern struct pinned_obj_table map_table;
void p_err(const char *fmt, ...);
void p_info(const char *fmt, ...);
bool is_prefix(const char *pfx, const char *str);
void fprint_hex(FILE *f, void *arg, unsigned int n, const char *sep);
void usage(void) __noreturn;
struct pinned_obj_table {
DECLARE_HASHTABLE(table, 16);
};
struct pinned_obj {
__u32 id;
char *path;
struct hlist_node hash;
};
int build_pinned_obj_table(struct pinned_obj_table *table,
enum bpf_obj_type type);
void delete_pinned_obj_table(struct pinned_obj_table *tab);
void print_dev_plain(__u32 ifindex, __u64 ns_dev, __u64 ns_inode);
void print_dev_json(__u32 ifindex, __u64 ns_dev, __u64 ns_inode);
struct cmd {
const char *cmd;
int (*func)(int argc, char **argv);
};
int cmd_select(const struct cmd *cmds, int argc, char **argv,
int (*help)(int argc, char **argv));
int get_fd_type(int fd);
const char *get_fd_type_name(enum bpf_obj_type type);
char *get_fdinfo(int fd, const char *key);
int open_obj_pinned(char *path, bool quiet);
int open_obj_pinned_any(char *path, enum bpf_obj_type exp_type);
int do_pin_any(int argc, char **argv, int (*get_fd_by_id)(__u32));
int do_pin_fd(int fd, const char *name);
int do_prog(int argc, char **arg);
int do_map(int argc, char **arg);
int do_event_pipe(int argc, char **argv);
int do_cgroup(int argc, char **arg);
int do_perf(int argc, char **arg);
int prog_parse_fd(int *argc, char ***argv);
int map_parse_fd(int *argc, char ***argv);
int map_parse_fd_and_info(int *argc, char ***argv, void *info, __u32 *info_len);
void disasm_print_insn(unsigned char *image, ssize_t len, int opcodes,
const char *arch);
void print_data_json(uint8_t *data, size_t len);
void print_hex_data_json(uint8_t *data, size_t len);
unsigned int get_page_size(void);
unsigned int get_possible_cpus(void);
const char *ifindex_to_bfd_name_ns(__u32 ifindex, __u64 ns_dev, __u64 ns_ino);
struct btf_dumper {
const struct btf *btf;
json_writer_t *jw;
bool is_plain_text;
};
/* btf_dumper_type - print data along with type information
* @d: an instance containing context for dumping types
* @type_id: index in btf->types array. this points to the type to be dumped
* @data: pointer the actual data, i.e. the values to be printed
*
* Returns zero on success and negative error code otherwise
*/
int btf_dumper_type(const struct btf_dumper *d, __u32 type_id,
const void *data);
#endif