linux/tools/lib/bpf/libbpf.h
Andrii Nakryiko d10ef2b825 libbpf: Unify low-level BPF_PROG_LOAD APIs into bpf_prog_load()
Add a new unified OPTS-based low-level API for program loading,
bpf_prog_load() ([0]).  bpf_prog_load() accepts few "mandatory"
parameters as input arguments (program type, name, license,
instructions) and all the other optional (as in not required to specify
for all types of BPF programs) fields into struct bpf_prog_load_opts.

This makes all the other non-extensible APIs variant for BPF_PROG_LOAD
obsolete and they are slated for deprecation in libbpf v0.7:
  - bpf_load_program();
  - bpf_load_program_xattr();
  - bpf_verify_program().

Implementation-wise, internal helper libbpf__bpf_prog_load is refactored
to become a public bpf_prog_load() API. struct bpf_prog_load_params used
internally is replaced by public struct bpf_prog_load_opts.

Unfortunately, while conceptually all this is pretty straightforward,
the biggest complication comes from the already existing bpf_prog_load()
*high-level* API, which has nothing to do with BPF_PROG_LOAD command.

We try really hard to have a new API named bpf_prog_load(), though,
because it maps naturally to BPF_PROG_LOAD command.

For that, we rename old bpf_prog_load() into bpf_prog_load_deprecated()
and mark it as COMPAT_VERSION() for shared library users compiled
against old version of libbpf. Statically linked users and shared lib
users compiled against new version of libbpf headers will get "rerouted"
to bpf_prog_deprecated() through a macro helper that decides whether to
use new or old bpf_prog_load() based on number of input arguments (see
___libbpf_overload in libbpf_common.h).

To test that existing
bpf_prog_load()-using code compiles and works as expected, I've compiled
and ran selftests as is. I had to remove (locally) selftest/bpf/Makefile
-Dbpf_prog_load=bpf_prog_test_load hack because it was conflicting with
the macro-based overload approach. I don't expect anyone else to do
something like this in practice, though. This is testing-specific way to
replace bpf_prog_load() calls with special testing variant of it, which
adds extra prog_flags value. After testing I kept this selftests hack,
but ensured that we use a new bpf_prog_load_deprecated name for this.

This patch also marks bpf_prog_load() and bpf_prog_load_xattr() as deprecated.
bpf_object interface has to be used for working with struct bpf_program.
Libbpf doesn't support loading just a bpf_program.

The silver lining is that when we get to libbpf 1.0 all these
complication will be gone and we'll have one clean bpf_prog_load()
low-level API with no backwards compatibility hackery surrounding it.

  [0] Closes: https://github.com/libbpf/libbpf/issues/284

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20211103220845.2676888-4-andrii@kernel.org
2021-11-07 08:34:23 -08:00

1032 lines
38 KiB
C

/* SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause) */
/*
* Common eBPF ELF object loading operations.
*
* Copyright (C) 2013-2015 Alexei Starovoitov <ast@kernel.org>
* Copyright (C) 2015 Wang Nan <wangnan0@huawei.com>
* Copyright (C) 2015 Huawei Inc.
*/
#ifndef __LIBBPF_LIBBPF_H
#define __LIBBPF_LIBBPF_H
#include <stdarg.h>
#include <stdio.h>
#include <stdint.h>
#include <stdbool.h>
#include <sys/types.h> // for size_t
#include <linux/bpf.h>
#include "libbpf_common.h"
#include "libbpf_legacy.h"
#ifdef __cplusplus
extern "C" {
#endif
enum libbpf_errno {
__LIBBPF_ERRNO__START = 4000,
/* Something wrong in libelf */
LIBBPF_ERRNO__LIBELF = __LIBBPF_ERRNO__START,
LIBBPF_ERRNO__FORMAT, /* BPF object format invalid */
LIBBPF_ERRNO__KVERSION, /* Incorrect or no 'version' section */
LIBBPF_ERRNO__ENDIAN, /* Endian mismatch */
LIBBPF_ERRNO__INTERNAL, /* Internal error in libbpf */
LIBBPF_ERRNO__RELOC, /* Relocation failed */
LIBBPF_ERRNO__LOAD, /* Load program failure for unknown reason */
LIBBPF_ERRNO__VERIFY, /* Kernel verifier blocks program loading */
LIBBPF_ERRNO__PROG2BIG, /* Program too big */
LIBBPF_ERRNO__KVER, /* Incorrect kernel version */
LIBBPF_ERRNO__PROGTYPE, /* Kernel doesn't support this program type */
LIBBPF_ERRNO__WRNGPID, /* Wrong pid in netlink message */
LIBBPF_ERRNO__INVSEQ, /* Invalid netlink sequence */
LIBBPF_ERRNO__NLPARSE, /* netlink parsing error */
__LIBBPF_ERRNO__END,
};
LIBBPF_API int libbpf_strerror(int err, char *buf, size_t size);
enum libbpf_print_level {
LIBBPF_WARN,
LIBBPF_INFO,
LIBBPF_DEBUG,
};
typedef int (*libbpf_print_fn_t)(enum libbpf_print_level level,
const char *, va_list ap);
LIBBPF_API libbpf_print_fn_t libbpf_set_print(libbpf_print_fn_t fn);
/* Hide internal to user */
struct bpf_object;
struct bpf_object_open_attr {
const char *file;
enum bpf_prog_type prog_type;
};
struct bpf_object_open_opts {
/* size of this struct, for forward/backward compatiblity */
size_t sz;
/* object name override, if provided:
* - for object open from file, this will override setting object
* name from file path's base name;
* - for object open from memory buffer, this will specify an object
* name and will override default "<addr>-<buf-size>" name;
*/
const char *object_name;
/* parse map definitions non-strictly, allowing extra attributes/data */
bool relaxed_maps;
/* DEPRECATED: handle CO-RE relocations non-strictly, allowing failures.
* Value is ignored. Relocations always are processed non-strictly.
* Non-relocatable instructions are replaced with invalid ones to
* prevent accidental errors.
* */
LIBBPF_DEPRECATED_SINCE(0, 6, "field has no effect")
bool relaxed_core_relocs;
/* maps that set the 'pinning' attribute in their definition will have
* their pin_path attribute set to a file in this directory, and be
* auto-pinned to that path on load; defaults to "/sys/fs/bpf".
*/
const char *pin_root_path;
LIBBPF_DEPRECATED_SINCE(0, 7, "use bpf_program__set_attach_target() on each individual bpf_program")
__u32 attach_prog_fd;
/* Additional kernel config content that augments and overrides
* system Kconfig for CONFIG_xxx externs.
*/
const char *kconfig;
/* Path to the custom BTF to be used for BPF CO-RE relocations.
* This custom BTF completely replaces the use of vmlinux BTF
* for the purpose of CO-RE relocations.
* NOTE: any other BPF feature (e.g., fentry/fexit programs,
* struct_ops, etc) will need actual kernel BTF at /sys/kernel/btf/vmlinux.
*/
const char *btf_custom_path;
};
#define bpf_object_open_opts__last_field btf_custom_path
LIBBPF_API struct bpf_object *bpf_object__open(const char *path);
LIBBPF_API struct bpf_object *
bpf_object__open_file(const char *path, const struct bpf_object_open_opts *opts);
LIBBPF_API struct bpf_object *
bpf_object__open_mem(const void *obj_buf, size_t obj_buf_sz,
const struct bpf_object_open_opts *opts);
/* deprecated bpf_object__open variants */
LIBBPF_API struct bpf_object *
bpf_object__open_buffer(const void *obj_buf, size_t obj_buf_sz,
const char *name);
LIBBPF_API struct bpf_object *
bpf_object__open_xattr(struct bpf_object_open_attr *attr);
enum libbpf_pin_type {
LIBBPF_PIN_NONE,
/* PIN_BY_NAME: pin maps by name (in /sys/fs/bpf by default) */
LIBBPF_PIN_BY_NAME,
};
/* pin_maps and unpin_maps can both be called with a NULL path, in which case
* they will use the pin_path attribute of each map (and ignore all maps that
* don't have a pin_path set).
*/
LIBBPF_API int bpf_object__pin_maps(struct bpf_object *obj, const char *path);
LIBBPF_API int bpf_object__unpin_maps(struct bpf_object *obj,
const char *path);
LIBBPF_API int bpf_object__pin_programs(struct bpf_object *obj,
const char *path);
LIBBPF_API int bpf_object__unpin_programs(struct bpf_object *obj,
const char *path);
LIBBPF_API int bpf_object__pin(struct bpf_object *object, const char *path);
LIBBPF_API void bpf_object__close(struct bpf_object *object);
struct bpf_object_load_attr {
struct bpf_object *obj;
int log_level;
const char *target_btf_path;
};
/* Load/unload object into/from kernel */
LIBBPF_API int bpf_object__load(struct bpf_object *obj);
LIBBPF_API int bpf_object__load_xattr(struct bpf_object_load_attr *attr);
LIBBPF_DEPRECATED_SINCE(0, 6, "bpf_object__unload() is deprecated, use bpf_object__close() instead")
LIBBPF_API int bpf_object__unload(struct bpf_object *obj);
LIBBPF_API const char *bpf_object__name(const struct bpf_object *obj);
LIBBPF_API unsigned int bpf_object__kversion(const struct bpf_object *obj);
LIBBPF_API int bpf_object__set_kversion(struct bpf_object *obj, __u32 kern_version);
struct btf;
LIBBPF_API struct btf *bpf_object__btf(const struct bpf_object *obj);
LIBBPF_API int bpf_object__btf_fd(const struct bpf_object *obj);
LIBBPF_API struct bpf_program *
bpf_object__find_program_by_title(const struct bpf_object *obj,
const char *title);
LIBBPF_API struct bpf_program *
bpf_object__find_program_by_name(const struct bpf_object *obj,
const char *name);
LIBBPF_API LIBBPF_DEPRECATED_SINCE(0, 7, "track bpf_objects in application code instead")
struct bpf_object *bpf_object__next(struct bpf_object *prev);
#define bpf_object__for_each_safe(pos, tmp) \
for ((pos) = bpf_object__next(NULL), \
(tmp) = bpf_object__next(pos); \
(pos) != NULL; \
(pos) = (tmp), (tmp) = bpf_object__next(tmp))
typedef void (*bpf_object_clear_priv_t)(struct bpf_object *, void *);
LIBBPF_API int bpf_object__set_priv(struct bpf_object *obj, void *priv,
bpf_object_clear_priv_t clear_priv);
LIBBPF_API void *bpf_object__priv(const struct bpf_object *prog);
LIBBPF_API int
libbpf_prog_type_by_name(const char *name, enum bpf_prog_type *prog_type,
enum bpf_attach_type *expected_attach_type);
LIBBPF_API int libbpf_attach_type_by_name(const char *name,
enum bpf_attach_type *attach_type);
LIBBPF_API int libbpf_find_vmlinux_btf_id(const char *name,
enum bpf_attach_type attach_type);
/* Accessors of bpf_program */
struct bpf_program;
LIBBPF_API LIBBPF_DEPRECATED_SINCE(0, 7, "use bpf_object__next_program() instead")
struct bpf_program *bpf_program__next(struct bpf_program *prog,
const struct bpf_object *obj);
LIBBPF_API struct bpf_program *
bpf_object__next_program(const struct bpf_object *obj, struct bpf_program *prog);
#define bpf_object__for_each_program(pos, obj) \
for ((pos) = bpf_object__next_program((obj), NULL); \
(pos) != NULL; \
(pos) = bpf_object__next_program((obj), (pos)))
LIBBPF_API LIBBPF_DEPRECATED_SINCE(0, 7, "use bpf_object__prev_program() instead")
struct bpf_program *bpf_program__prev(struct bpf_program *prog,
const struct bpf_object *obj);
LIBBPF_API struct bpf_program *
bpf_object__prev_program(const struct bpf_object *obj, struct bpf_program *prog);
typedef void (*bpf_program_clear_priv_t)(struct bpf_program *, void *);
LIBBPF_API int bpf_program__set_priv(struct bpf_program *prog, void *priv,
bpf_program_clear_priv_t clear_priv);
LIBBPF_API void *bpf_program__priv(const struct bpf_program *prog);
LIBBPF_API void bpf_program__set_ifindex(struct bpf_program *prog,
__u32 ifindex);
LIBBPF_API const char *bpf_program__name(const struct bpf_program *prog);
LIBBPF_API const char *bpf_program__section_name(const struct bpf_program *prog);
LIBBPF_API LIBBPF_DEPRECATED("BPF program title is confusing term; please use bpf_program__section_name() instead")
const char *bpf_program__title(const struct bpf_program *prog, bool needs_copy);
LIBBPF_API bool bpf_program__autoload(const struct bpf_program *prog);
LIBBPF_API int bpf_program__set_autoload(struct bpf_program *prog, bool autoload);
/* returns program size in bytes */
LIBBPF_DEPRECATED_SINCE(0, 7, "use bpf_program__insn_cnt() instead")
LIBBPF_API size_t bpf_program__size(const struct bpf_program *prog);
struct bpf_insn;
/**
* @brief **bpf_program__insns()** gives read-only access to BPF program's
* underlying BPF instructions.
* @param prog BPF program for which to return instructions
* @return a pointer to an array of BPF instructions that belong to the
* specified BPF program
*
* Returned pointer is always valid and not NULL. Number of `struct bpf_insn`
* pointed to can be fetched using **bpf_program__insn_cnt()** API.
*
* Keep in mind, libbpf can modify and append/delete BPF program's
* instructions as it processes BPF object file and prepares everything for
* uploading into the kernel. So depending on the point in BPF object
* lifetime, **bpf_program__insns()** can return different sets of
* instructions. As an example, during BPF object load phase BPF program
* instructions will be CO-RE-relocated, BPF subprograms instructions will be
* appended, ldimm64 instructions will have FDs embedded, etc. So instructions
* returned before **bpf_object__load()** and after it might be quite
* different.
*/
LIBBPF_API const struct bpf_insn *bpf_program__insns(const struct bpf_program *prog);
/**
* @brief **bpf_program__insn_cnt()** returns number of `struct bpf_insn`'s
* that form specified BPF program.
* @param prog BPF program for which to return number of BPF instructions
*
* See **bpf_program__insns()** documentation for notes on how libbpf can
* change instructions and their count during different phases of
* **bpf_object** lifetime.
*/
LIBBPF_API size_t bpf_program__insn_cnt(const struct bpf_program *prog);
LIBBPF_DEPRECATED_SINCE(0, 6, "use bpf_object__load() instead")
LIBBPF_API int bpf_program__load(struct bpf_program *prog, const char *license, __u32 kern_version);
LIBBPF_API int bpf_program__fd(const struct bpf_program *prog);
LIBBPF_DEPRECATED_SINCE(0, 7, "multi-instance bpf_program support is deprecated")
LIBBPF_API int bpf_program__pin_instance(struct bpf_program *prog,
const char *path,
int instance);
LIBBPF_DEPRECATED_SINCE(0, 7, "multi-instance bpf_program support is deprecated")
LIBBPF_API int bpf_program__unpin_instance(struct bpf_program *prog,
const char *path,
int instance);
LIBBPF_API int bpf_program__pin(struct bpf_program *prog, const char *path);
LIBBPF_API int bpf_program__unpin(struct bpf_program *prog, const char *path);
LIBBPF_API void bpf_program__unload(struct bpf_program *prog);
struct bpf_link;
LIBBPF_API struct bpf_link *bpf_link__open(const char *path);
LIBBPF_API int bpf_link__fd(const struct bpf_link *link);
LIBBPF_API const char *bpf_link__pin_path(const struct bpf_link *link);
LIBBPF_API int bpf_link__pin(struct bpf_link *link, const char *path);
LIBBPF_API int bpf_link__unpin(struct bpf_link *link);
LIBBPF_API int bpf_link__update_program(struct bpf_link *link,
struct bpf_program *prog);
LIBBPF_API void bpf_link__disconnect(struct bpf_link *link);
LIBBPF_API int bpf_link__detach(struct bpf_link *link);
LIBBPF_API int bpf_link__destroy(struct bpf_link *link);
LIBBPF_API struct bpf_link *
bpf_program__attach(const struct bpf_program *prog);
struct bpf_perf_event_opts {
/* size of this struct, for forward/backward compatiblity */
size_t sz;
/* custom user-provided value fetchable through bpf_get_attach_cookie() */
__u64 bpf_cookie;
};
#define bpf_perf_event_opts__last_field bpf_cookie
LIBBPF_API struct bpf_link *
bpf_program__attach_perf_event(const struct bpf_program *prog, int pfd);
LIBBPF_API struct bpf_link *
bpf_program__attach_perf_event_opts(const struct bpf_program *prog, int pfd,
const struct bpf_perf_event_opts *opts);
struct bpf_kprobe_opts {
/* size of this struct, for forward/backward compatiblity */
size_t sz;
/* custom user-provided value fetchable through bpf_get_attach_cookie() */
__u64 bpf_cookie;
/* function's offset to install kprobe to */
size_t offset;
/* kprobe is return probe */
bool retprobe;
size_t :0;
};
#define bpf_kprobe_opts__last_field retprobe
LIBBPF_API struct bpf_link *
bpf_program__attach_kprobe(const struct bpf_program *prog, bool retprobe,
const char *func_name);
LIBBPF_API struct bpf_link *
bpf_program__attach_kprobe_opts(const struct bpf_program *prog,
const char *func_name,
const struct bpf_kprobe_opts *opts);
struct bpf_uprobe_opts {
/* size of this struct, for forward/backward compatiblity */
size_t sz;
/* offset of kernel reference counted USDT semaphore, added in
* a6ca88b241d5 ("trace_uprobe: support reference counter in fd-based uprobe")
*/
size_t ref_ctr_offset;
/* custom user-provided value fetchable through bpf_get_attach_cookie() */
__u64 bpf_cookie;
/* uprobe is return probe, invoked at function return time */
bool retprobe;
size_t :0;
};
#define bpf_uprobe_opts__last_field retprobe
LIBBPF_API struct bpf_link *
bpf_program__attach_uprobe(const struct bpf_program *prog, bool retprobe,
pid_t pid, const char *binary_path,
size_t func_offset);
LIBBPF_API struct bpf_link *
bpf_program__attach_uprobe_opts(const struct bpf_program *prog, pid_t pid,
const char *binary_path, size_t func_offset,
const struct bpf_uprobe_opts *opts);
struct bpf_tracepoint_opts {
/* size of this struct, for forward/backward compatiblity */
size_t sz;
/* custom user-provided value fetchable through bpf_get_attach_cookie() */
__u64 bpf_cookie;
};
#define bpf_tracepoint_opts__last_field bpf_cookie
LIBBPF_API struct bpf_link *
bpf_program__attach_tracepoint(const struct bpf_program *prog,
const char *tp_category,
const char *tp_name);
LIBBPF_API struct bpf_link *
bpf_program__attach_tracepoint_opts(const struct bpf_program *prog,
const char *tp_category,
const char *tp_name,
const struct bpf_tracepoint_opts *opts);
LIBBPF_API struct bpf_link *
bpf_program__attach_raw_tracepoint(const struct bpf_program *prog,
const char *tp_name);
LIBBPF_API struct bpf_link *
bpf_program__attach_trace(const struct bpf_program *prog);
LIBBPF_API struct bpf_link *
bpf_program__attach_lsm(const struct bpf_program *prog);
LIBBPF_API struct bpf_link *
bpf_program__attach_cgroup(const struct bpf_program *prog, int cgroup_fd);
LIBBPF_API struct bpf_link *
bpf_program__attach_netns(const struct bpf_program *prog, int netns_fd);
LIBBPF_API struct bpf_link *
bpf_program__attach_xdp(const struct bpf_program *prog, int ifindex);
LIBBPF_API struct bpf_link *
bpf_program__attach_freplace(const struct bpf_program *prog,
int target_fd, const char *attach_func_name);
struct bpf_map;
LIBBPF_API struct bpf_link *bpf_map__attach_struct_ops(const struct bpf_map *map);
struct bpf_iter_attach_opts {
size_t sz; /* size of this struct for forward/backward compatibility */
union bpf_iter_link_info *link_info;
__u32 link_info_len;
};
#define bpf_iter_attach_opts__last_field link_info_len
LIBBPF_API struct bpf_link *
bpf_program__attach_iter(const struct bpf_program *prog,
const struct bpf_iter_attach_opts *opts);
/*
* Libbpf allows callers to adjust BPF programs before being loaded
* into kernel. One program in an object file can be transformed into
* multiple variants to be attached to different hooks.
*
* bpf_program_prep_t, bpf_program__set_prep and bpf_program__nth_fd
* form an API for this purpose.
*
* - bpf_program_prep_t:
* Defines a 'preprocessor', which is a caller defined function
* passed to libbpf through bpf_program__set_prep(), and will be
* called before program is loaded. The processor should adjust
* the program one time for each instance according to the instance id
* passed to it.
*
* - bpf_program__set_prep:
* Attaches a preprocessor to a BPF program. The number of instances
* that should be created is also passed through this function.
*
* - bpf_program__nth_fd:
* After the program is loaded, get resulting FD of a given instance
* of the BPF program.
*
* If bpf_program__set_prep() is not used, the program would be loaded
* without adjustment during bpf_object__load(). The program has only
* one instance. In this case bpf_program__fd(prog) is equal to
* bpf_program__nth_fd(prog, 0).
*/
LIBBPF_DEPRECATED_SINCE(0, 7, "use bpf_program__insns() for getting bpf_program instructions")
struct bpf_prog_prep_result {
/*
* If not NULL, load new instruction array.
* If set to NULL, don't load this instance.
*/
struct bpf_insn *new_insn_ptr;
int new_insn_cnt;
/* If not NULL, result FD is written to it. */
int *pfd;
};
/*
* Parameters of bpf_program_prep_t:
* - prog: The bpf_program being loaded.
* - n: Index of instance being generated.
* - insns: BPF instructions array.
* - insns_cnt:Number of instructions in insns.
* - res: Output parameter, result of transformation.
*
* Return value:
* - Zero: pre-processing success.
* - Non-zero: pre-processing error, stop loading.
*/
typedef int (*bpf_program_prep_t)(struct bpf_program *prog, int n,
struct bpf_insn *insns, int insns_cnt,
struct bpf_prog_prep_result *res);
LIBBPF_DEPRECATED_SINCE(0, 7, "use bpf_program__insns() for getting bpf_program instructions")
LIBBPF_API int bpf_program__set_prep(struct bpf_program *prog, int nr_instance,
bpf_program_prep_t prep);
LIBBPF_DEPRECATED_SINCE(0, 7, "multi-instance bpf_program support is deprecated")
LIBBPF_API int bpf_program__nth_fd(const struct bpf_program *prog, int n);
/*
* Adjust type of BPF program. Default is kprobe.
*/
LIBBPF_API int bpf_program__set_socket_filter(struct bpf_program *prog);
LIBBPF_API int bpf_program__set_tracepoint(struct bpf_program *prog);
LIBBPF_API int bpf_program__set_raw_tracepoint(struct bpf_program *prog);
LIBBPF_API int bpf_program__set_kprobe(struct bpf_program *prog);
LIBBPF_API int bpf_program__set_lsm(struct bpf_program *prog);
LIBBPF_API int bpf_program__set_sched_cls(struct bpf_program *prog);
LIBBPF_API int bpf_program__set_sched_act(struct bpf_program *prog);
LIBBPF_API int bpf_program__set_xdp(struct bpf_program *prog);
LIBBPF_API int bpf_program__set_perf_event(struct bpf_program *prog);
LIBBPF_API int bpf_program__set_tracing(struct bpf_program *prog);
LIBBPF_API int bpf_program__set_struct_ops(struct bpf_program *prog);
LIBBPF_API int bpf_program__set_extension(struct bpf_program *prog);
LIBBPF_API int bpf_program__set_sk_lookup(struct bpf_program *prog);
LIBBPF_API enum bpf_prog_type bpf_program__get_type(const struct bpf_program *prog);
LIBBPF_API void bpf_program__set_type(struct bpf_program *prog,
enum bpf_prog_type type);
LIBBPF_API enum bpf_attach_type
bpf_program__get_expected_attach_type(const struct bpf_program *prog);
LIBBPF_API void
bpf_program__set_expected_attach_type(struct bpf_program *prog,
enum bpf_attach_type type);
LIBBPF_API int
bpf_program__set_attach_target(struct bpf_program *prog, int attach_prog_fd,
const char *attach_func_name);
LIBBPF_API bool bpf_program__is_socket_filter(const struct bpf_program *prog);
LIBBPF_API bool bpf_program__is_tracepoint(const struct bpf_program *prog);
LIBBPF_API bool bpf_program__is_raw_tracepoint(const struct bpf_program *prog);
LIBBPF_API bool bpf_program__is_kprobe(const struct bpf_program *prog);
LIBBPF_API bool bpf_program__is_lsm(const struct bpf_program *prog);
LIBBPF_API bool bpf_program__is_sched_cls(const struct bpf_program *prog);
LIBBPF_API bool bpf_program__is_sched_act(const struct bpf_program *prog);
LIBBPF_API bool bpf_program__is_xdp(const struct bpf_program *prog);
LIBBPF_API bool bpf_program__is_perf_event(const struct bpf_program *prog);
LIBBPF_API bool bpf_program__is_tracing(const struct bpf_program *prog);
LIBBPF_API bool bpf_program__is_struct_ops(const struct bpf_program *prog);
LIBBPF_API bool bpf_program__is_extension(const struct bpf_program *prog);
LIBBPF_API bool bpf_program__is_sk_lookup(const struct bpf_program *prog);
/*
* No need for __attribute__((packed)), all members of 'bpf_map_def'
* are all aligned. In addition, using __attribute__((packed))
* would trigger a -Wpacked warning message, and lead to an error
* if -Werror is set.
*/
struct bpf_map_def {
unsigned int type;
unsigned int key_size;
unsigned int value_size;
unsigned int max_entries;
unsigned int map_flags;
};
/**
* @brief **bpf_object__find_map_by_name()** returns BPF map of
* the given name, if it exists within the passed BPF object
* @param obj BPF object
* @param name name of the BPF map
* @return BPF map instance, if such map exists within the BPF object;
* or NULL otherwise.
*/
LIBBPF_API struct bpf_map *
bpf_object__find_map_by_name(const struct bpf_object *obj, const char *name);
LIBBPF_API int
bpf_object__find_map_fd_by_name(const struct bpf_object *obj, const char *name);
/*
* Get bpf_map through the offset of corresponding struct bpf_map_def
* in the BPF object file.
*/
LIBBPF_API struct bpf_map *
bpf_object__find_map_by_offset(struct bpf_object *obj, size_t offset);
LIBBPF_API LIBBPF_DEPRECATED_SINCE(0, 7, "use bpf_object__next_map() instead")
struct bpf_map *bpf_map__next(const struct bpf_map *map, const struct bpf_object *obj);
LIBBPF_API struct bpf_map *
bpf_object__next_map(const struct bpf_object *obj, const struct bpf_map *map);
#define bpf_object__for_each_map(pos, obj) \
for ((pos) = bpf_object__next_map((obj), NULL); \
(pos) != NULL; \
(pos) = bpf_object__next_map((obj), (pos)))
#define bpf_map__for_each bpf_object__for_each_map
LIBBPF_API LIBBPF_DEPRECATED_SINCE(0, 7, "use bpf_object__prev_map() instead")
struct bpf_map *bpf_map__prev(const struct bpf_map *map, const struct bpf_object *obj);
LIBBPF_API struct bpf_map *
bpf_object__prev_map(const struct bpf_object *obj, const struct bpf_map *map);
/**
* @brief **bpf_map__fd()** gets the file descriptor of the passed
* BPF map
* @param map the BPF map instance
* @return the file descriptor; or -EINVAL in case of an error
*/
LIBBPF_API int bpf_map__fd(const struct bpf_map *map);
LIBBPF_API int bpf_map__reuse_fd(struct bpf_map *map, int fd);
/* get map definition */
LIBBPF_API const struct bpf_map_def *bpf_map__def(const struct bpf_map *map);
/* get map name */
LIBBPF_API const char *bpf_map__name(const struct bpf_map *map);
/* get/set map type */
LIBBPF_API enum bpf_map_type bpf_map__type(const struct bpf_map *map);
LIBBPF_API int bpf_map__set_type(struct bpf_map *map, enum bpf_map_type type);
/* get/set map size (max_entries) */
LIBBPF_API __u32 bpf_map__max_entries(const struct bpf_map *map);
LIBBPF_API int bpf_map__set_max_entries(struct bpf_map *map, __u32 max_entries);
LIBBPF_API int bpf_map__resize(struct bpf_map *map, __u32 max_entries);
/* get/set map flags */
LIBBPF_API __u32 bpf_map__map_flags(const struct bpf_map *map);
LIBBPF_API int bpf_map__set_map_flags(struct bpf_map *map, __u32 flags);
/* get/set map NUMA node */
LIBBPF_API __u32 bpf_map__numa_node(const struct bpf_map *map);
LIBBPF_API int bpf_map__set_numa_node(struct bpf_map *map, __u32 numa_node);
/* get/set map key size */
LIBBPF_API __u32 bpf_map__key_size(const struct bpf_map *map);
LIBBPF_API int bpf_map__set_key_size(struct bpf_map *map, __u32 size);
/* get/set map value size */
LIBBPF_API __u32 bpf_map__value_size(const struct bpf_map *map);
LIBBPF_API int bpf_map__set_value_size(struct bpf_map *map, __u32 size);
/* get map key/value BTF type IDs */
LIBBPF_API __u32 bpf_map__btf_key_type_id(const struct bpf_map *map);
LIBBPF_API __u32 bpf_map__btf_value_type_id(const struct bpf_map *map);
/* get/set map if_index */
LIBBPF_API __u32 bpf_map__ifindex(const struct bpf_map *map);
LIBBPF_API int bpf_map__set_ifindex(struct bpf_map *map, __u32 ifindex);
/* get/set map map_extra flags */
LIBBPF_API __u64 bpf_map__map_extra(const struct bpf_map *map);
LIBBPF_API int bpf_map__set_map_extra(struct bpf_map *map, __u64 map_extra);
typedef void (*bpf_map_clear_priv_t)(struct bpf_map *, void *);
LIBBPF_API int bpf_map__set_priv(struct bpf_map *map, void *priv,
bpf_map_clear_priv_t clear_priv);
LIBBPF_API void *bpf_map__priv(const struct bpf_map *map);
LIBBPF_API int bpf_map__set_initial_value(struct bpf_map *map,
const void *data, size_t size);
LIBBPF_API const void *bpf_map__initial_value(struct bpf_map *map, size_t *psize);
LIBBPF_API bool bpf_map__is_offload_neutral(const struct bpf_map *map);
/**
* @brief **bpf_map__is_internal()** tells the caller whether or not the
* passed map is a special map created by libbpf automatically for things like
* global variables, __ksym externs, Kconfig values, etc
* @param map the bpf_map
* @return true, if the map is an internal map; false, otherwise
*/
LIBBPF_API bool bpf_map__is_internal(const struct bpf_map *map);
LIBBPF_API int bpf_map__set_pin_path(struct bpf_map *map, const char *path);
LIBBPF_API const char *bpf_map__get_pin_path(const struct bpf_map *map);
LIBBPF_API const char *bpf_map__pin_path(const struct bpf_map *map);
LIBBPF_API bool bpf_map__is_pinned(const struct bpf_map *map);
LIBBPF_API int bpf_map__pin(struct bpf_map *map, const char *path);
LIBBPF_API int bpf_map__unpin(struct bpf_map *map, const char *path);
LIBBPF_API int bpf_map__set_inner_map_fd(struct bpf_map *map, int fd);
LIBBPF_API struct bpf_map *bpf_map__inner_map(struct bpf_map *map);
/**
* @brief **libbpf_get_error()** extracts the error code from the passed
* pointer
* @param ptr pointer returned from libbpf API function
* @return error code; or 0 if no error occured
*
* Many libbpf API functions which return pointers have logic to encode error
* codes as pointers, and do not return NULL. Meaning **libbpf_get_error()**
* should be used on the return value from these functions immediately after
* calling the API function, with no intervening calls that could clobber the
* `errno` variable. Consult the individual functions documentation to verify
* if this logic applies should be used.
*
* For these API functions, if `libbpf_set_strict_mode(LIBBPF_STRICT_CLEAN_PTRS)`
* is enabled, NULL is returned on error instead.
*
* If ptr is NULL, then errno should be already set by the failing
* API, because libbpf never returns NULL on success and it now always
* sets errno on error.
*
* Example usage:
*
* struct perf_buffer *pb;
*
* pb = perf_buffer__new(bpf_map__fd(obj->maps.events), PERF_BUFFER_PAGES, &opts);
* err = libbpf_get_error(pb);
* if (err) {
* pb = NULL;
* fprintf(stderr, "failed to open perf buffer: %d\n", err);
* goto cleanup;
* }
*/
LIBBPF_API long libbpf_get_error(const void *ptr);
struct bpf_prog_load_attr {
const char *file;
enum bpf_prog_type prog_type;
enum bpf_attach_type expected_attach_type;
int ifindex;
int log_level;
int prog_flags;
};
LIBBPF_API int bpf_prog_load_xattr(const struct bpf_prog_load_attr *attr,
struct bpf_object **pobj, int *prog_fd);
LIBBPF_DEPRECATED_SINCE(0, 7, "use bpf_object__open() and bpf_object__load() instead")
LIBBPF_API int bpf_prog_load_deprecated(const char *file, enum bpf_prog_type type,
struct bpf_object **pobj, int *prog_fd);
/* XDP related API */
struct xdp_link_info {
__u32 prog_id;
__u32 drv_prog_id;
__u32 hw_prog_id;
__u32 skb_prog_id;
__u8 attach_mode;
};
struct bpf_xdp_set_link_opts {
size_t sz;
int old_fd;
size_t :0;
};
#define bpf_xdp_set_link_opts__last_field old_fd
LIBBPF_API int bpf_set_link_xdp_fd(int ifindex, int fd, __u32 flags);
LIBBPF_API int bpf_set_link_xdp_fd_opts(int ifindex, int fd, __u32 flags,
const struct bpf_xdp_set_link_opts *opts);
LIBBPF_API int bpf_get_link_xdp_id(int ifindex, __u32 *prog_id, __u32 flags);
LIBBPF_API int bpf_get_link_xdp_info(int ifindex, struct xdp_link_info *info,
size_t info_size, __u32 flags);
/* TC related API */
enum bpf_tc_attach_point {
BPF_TC_INGRESS = 1 << 0,
BPF_TC_EGRESS = 1 << 1,
BPF_TC_CUSTOM = 1 << 2,
};
#define BPF_TC_PARENT(a, b) \
((((a) << 16) & 0xFFFF0000U) | ((b) & 0x0000FFFFU))
enum bpf_tc_flags {
BPF_TC_F_REPLACE = 1 << 0,
};
struct bpf_tc_hook {
size_t sz;
int ifindex;
enum bpf_tc_attach_point attach_point;
__u32 parent;
size_t :0;
};
#define bpf_tc_hook__last_field parent
struct bpf_tc_opts {
size_t sz;
int prog_fd;
__u32 flags;
__u32 prog_id;
__u32 handle;
__u32 priority;
size_t :0;
};
#define bpf_tc_opts__last_field priority
LIBBPF_API int bpf_tc_hook_create(struct bpf_tc_hook *hook);
LIBBPF_API int bpf_tc_hook_destroy(struct bpf_tc_hook *hook);
LIBBPF_API int bpf_tc_attach(const struct bpf_tc_hook *hook,
struct bpf_tc_opts *opts);
LIBBPF_API int bpf_tc_detach(const struct bpf_tc_hook *hook,
const struct bpf_tc_opts *opts);
LIBBPF_API int bpf_tc_query(const struct bpf_tc_hook *hook,
struct bpf_tc_opts *opts);
/* Ring buffer APIs */
struct ring_buffer;
typedef int (*ring_buffer_sample_fn)(void *ctx, void *data, size_t size);
struct ring_buffer_opts {
size_t sz; /* size of this struct, for forward/backward compatiblity */
};
#define ring_buffer_opts__last_field sz
LIBBPF_API struct ring_buffer *
ring_buffer__new(int map_fd, ring_buffer_sample_fn sample_cb, void *ctx,
const struct ring_buffer_opts *opts);
LIBBPF_API void ring_buffer__free(struct ring_buffer *rb);
LIBBPF_API int ring_buffer__add(struct ring_buffer *rb, int map_fd,
ring_buffer_sample_fn sample_cb, void *ctx);
LIBBPF_API int ring_buffer__poll(struct ring_buffer *rb, int timeout_ms);
LIBBPF_API int ring_buffer__consume(struct ring_buffer *rb);
LIBBPF_API int ring_buffer__epoll_fd(const struct ring_buffer *rb);
/* Perf buffer APIs */
struct perf_buffer;
typedef void (*perf_buffer_sample_fn)(void *ctx, int cpu,
void *data, __u32 size);
typedef void (*perf_buffer_lost_fn)(void *ctx, int cpu, __u64 cnt);
/* common use perf buffer options */
struct perf_buffer_opts {
/* if specified, sample_cb is called for each sample */
perf_buffer_sample_fn sample_cb;
/* if specified, lost_cb is called for each batch of lost samples */
perf_buffer_lost_fn lost_cb;
/* ctx is provided to sample_cb and lost_cb */
void *ctx;
};
LIBBPF_API struct perf_buffer *
perf_buffer__new(int map_fd, size_t page_cnt,
const struct perf_buffer_opts *opts);
enum bpf_perf_event_ret {
LIBBPF_PERF_EVENT_DONE = 0,
LIBBPF_PERF_EVENT_ERROR = -1,
LIBBPF_PERF_EVENT_CONT = -2,
};
struct perf_event_header;
typedef enum bpf_perf_event_ret
(*perf_buffer_event_fn)(void *ctx, int cpu, struct perf_event_header *event);
/* raw perf buffer options, giving most power and control */
struct perf_buffer_raw_opts {
/* perf event attrs passed directly into perf_event_open() */
struct perf_event_attr *attr;
/* raw event callback */
perf_buffer_event_fn event_cb;
/* ctx is provided to event_cb */
void *ctx;
/* if cpu_cnt == 0, open all on all possible CPUs (up to the number of
* max_entries of given PERF_EVENT_ARRAY map)
*/
int cpu_cnt;
/* if cpu_cnt > 0, cpus is an array of CPUs to open ring buffers on */
int *cpus;
/* if cpu_cnt > 0, map_keys specify map keys to set per-CPU FDs for */
int *map_keys;
};
LIBBPF_API struct perf_buffer *
perf_buffer__new_raw(int map_fd, size_t page_cnt,
const struct perf_buffer_raw_opts *opts);
LIBBPF_API void perf_buffer__free(struct perf_buffer *pb);
LIBBPF_API int perf_buffer__epoll_fd(const struct perf_buffer *pb);
LIBBPF_API int perf_buffer__poll(struct perf_buffer *pb, int timeout_ms);
LIBBPF_API int perf_buffer__consume(struct perf_buffer *pb);
LIBBPF_API int perf_buffer__consume_buffer(struct perf_buffer *pb, size_t buf_idx);
LIBBPF_API size_t perf_buffer__buffer_cnt(const struct perf_buffer *pb);
LIBBPF_API int perf_buffer__buffer_fd(const struct perf_buffer *pb, size_t buf_idx);
typedef enum bpf_perf_event_ret
(*bpf_perf_event_print_t)(struct perf_event_header *hdr,
void *private_data);
LIBBPF_API enum bpf_perf_event_ret
bpf_perf_event_read_simple(void *mmap_mem, size_t mmap_size, size_t page_size,
void **copy_mem, size_t *copy_size,
bpf_perf_event_print_t fn, void *private_data);
struct bpf_prog_linfo;
struct bpf_prog_info;
LIBBPF_API void bpf_prog_linfo__free(struct bpf_prog_linfo *prog_linfo);
LIBBPF_API struct bpf_prog_linfo *
bpf_prog_linfo__new(const struct bpf_prog_info *info);
LIBBPF_API const struct bpf_line_info *
bpf_prog_linfo__lfind_addr_func(const struct bpf_prog_linfo *prog_linfo,
__u64 addr, __u32 func_idx, __u32 nr_skip);
LIBBPF_API const struct bpf_line_info *
bpf_prog_linfo__lfind(const struct bpf_prog_linfo *prog_linfo,
__u32 insn_off, __u32 nr_skip);
/*
* Probe for supported system features
*
* Note that running many of these probes in a short amount of time can cause
* the kernel to reach the maximal size of lockable memory allowed for the
* user, causing subsequent probes to fail. In this case, the caller may want
* to adjust that limit with setrlimit().
*/
LIBBPF_API bool bpf_probe_prog_type(enum bpf_prog_type prog_type,
__u32 ifindex);
LIBBPF_API bool bpf_probe_map_type(enum bpf_map_type map_type, __u32 ifindex);
LIBBPF_API bool bpf_probe_helper(enum bpf_func_id id,
enum bpf_prog_type prog_type, __u32 ifindex);
LIBBPF_API bool bpf_probe_large_insn_limit(__u32 ifindex);
/*
* Get bpf_prog_info in continuous memory
*
* struct bpf_prog_info has multiple arrays. The user has option to choose
* arrays to fetch from kernel. The following APIs provide an uniform way to
* fetch these data. All arrays in bpf_prog_info are stored in a single
* continuous memory region. This makes it easy to store the info in a
* file.
*
* Before writing bpf_prog_info_linear to files, it is necessary to
* translate pointers in bpf_prog_info to offsets. Helper functions
* bpf_program__bpil_addr_to_offs() and bpf_program__bpil_offs_to_addr()
* are introduced to switch between pointers and offsets.
*
* Examples:
* # To fetch map_ids and prog_tags:
* __u64 arrays = (1UL << BPF_PROG_INFO_MAP_IDS) |
* (1UL << BPF_PROG_INFO_PROG_TAGS);
* struct bpf_prog_info_linear *info_linear =
* bpf_program__get_prog_info_linear(fd, arrays);
*
* # To save data in file
* bpf_program__bpil_addr_to_offs(info_linear);
* write(f, info_linear, sizeof(*info_linear) + info_linear->data_len);
*
* # To read data from file
* read(f, info_linear, <proper_size>);
* bpf_program__bpil_offs_to_addr(info_linear);
*/
enum bpf_prog_info_array {
BPF_PROG_INFO_FIRST_ARRAY = 0,
BPF_PROG_INFO_JITED_INSNS = 0,
BPF_PROG_INFO_XLATED_INSNS,
BPF_PROG_INFO_MAP_IDS,
BPF_PROG_INFO_JITED_KSYMS,
BPF_PROG_INFO_JITED_FUNC_LENS,
BPF_PROG_INFO_FUNC_INFO,
BPF_PROG_INFO_LINE_INFO,
BPF_PROG_INFO_JITED_LINE_INFO,
BPF_PROG_INFO_PROG_TAGS,
BPF_PROG_INFO_LAST_ARRAY,
};
struct bpf_prog_info_linear {
/* size of struct bpf_prog_info, when the tool is compiled */
__u32 info_len;
/* total bytes allocated for data, round up to 8 bytes */
__u32 data_len;
/* which arrays are included in data */
__u64 arrays;
struct bpf_prog_info info;
__u8 data[];
};
LIBBPF_DEPRECATED_SINCE(0, 6, "use a custom linear prog_info wrapper")
LIBBPF_API struct bpf_prog_info_linear *
bpf_program__get_prog_info_linear(int fd, __u64 arrays);
LIBBPF_DEPRECATED_SINCE(0, 6, "use a custom linear prog_info wrapper")
LIBBPF_API void
bpf_program__bpil_addr_to_offs(struct bpf_prog_info_linear *info_linear);
LIBBPF_DEPRECATED_SINCE(0, 6, "use a custom linear prog_info wrapper")
LIBBPF_API void
bpf_program__bpil_offs_to_addr(struct bpf_prog_info_linear *info_linear);
/**
* @brief **libbpf_num_possible_cpus()** is a helper function to get the
* number of possible CPUs that the host kernel supports and expects.
* @return number of possible CPUs; or error code on failure
*
* Example usage:
*
* int ncpus = libbpf_num_possible_cpus();
* if (ncpus < 0) {
* // error handling
* }
* long values[ncpus];
* bpf_map_lookup_elem(per_cpu_map_fd, key, values);
*/
LIBBPF_API int libbpf_num_possible_cpus(void);
struct bpf_map_skeleton {
const char *name;
struct bpf_map **map;
void **mmaped;
};
struct bpf_prog_skeleton {
const char *name;
struct bpf_program **prog;
struct bpf_link **link;
};
struct bpf_object_skeleton {
size_t sz; /* size of this struct, for forward/backward compatibility */
const char *name;
const void *data;
size_t data_sz;
struct bpf_object **obj;
int map_cnt;
int map_skel_sz; /* sizeof(struct bpf_skeleton_map) */
struct bpf_map_skeleton *maps;
int prog_cnt;
int prog_skel_sz; /* sizeof(struct bpf_skeleton_prog) */
struct bpf_prog_skeleton *progs;
};
LIBBPF_API int
bpf_object__open_skeleton(struct bpf_object_skeleton *s,
const struct bpf_object_open_opts *opts);
LIBBPF_API int bpf_object__load_skeleton(struct bpf_object_skeleton *s);
LIBBPF_API int bpf_object__attach_skeleton(struct bpf_object_skeleton *s);
LIBBPF_API void bpf_object__detach_skeleton(struct bpf_object_skeleton *s);
LIBBPF_API void bpf_object__destroy_skeleton(struct bpf_object_skeleton *s);
struct gen_loader_opts {
size_t sz; /* size of this struct, for forward/backward compatiblity */
const char *data;
const char *insns;
__u32 data_sz;
__u32 insns_sz;
};
#define gen_loader_opts__last_field insns_sz
LIBBPF_API int bpf_object__gen_loader(struct bpf_object *obj,
struct gen_loader_opts *opts);
enum libbpf_tristate {
TRI_NO = 0,
TRI_YES = 1,
TRI_MODULE = 2,
};
struct bpf_linker_opts {
/* size of this struct, for forward/backward compatiblity */
size_t sz;
};
#define bpf_linker_opts__last_field sz
struct bpf_linker_file_opts {
/* size of this struct, for forward/backward compatiblity */
size_t sz;
};
#define bpf_linker_file_opts__last_field sz
struct bpf_linker;
LIBBPF_API struct bpf_linker *bpf_linker__new(const char *filename, struct bpf_linker_opts *opts);
LIBBPF_API int bpf_linker__add_file(struct bpf_linker *linker,
const char *filename,
const struct bpf_linker_file_opts *opts);
LIBBPF_API int bpf_linker__finalize(struct bpf_linker *linker);
LIBBPF_API void bpf_linker__free(struct bpf_linker *linker);
#ifdef __cplusplus
} /* extern "C" */
#endif
#endif /* __LIBBPF_LIBBPF_H */