Functions
Link-related functions
int	bpf_link_detach (int link_fd)
	Detach a link. More...

int	bpf_link_get_fd_by_id (__u32 id)
	Get a file descriptor referring to a link with a given ID. More...

int	bpf_link_get_next_id (__u32 start_id, __u32 *next_id)
	Look for the next link ID greater than a given ID. More...

Map-related functions
int	bpf_map_create (enum bpf_map_type map_type, const char map_name, __u32 key_size, __u32 value_size, __u32 max_entries, const struct bpf_map_create_opts opts)
	Create a new map. More...

int	bpf_map_delete_elem (int fd, const void *key)
	Look up and delete an element by key in a specified map. More...

int	bpf_map_get_fd_by_id (__u32 id)
	Get a file descriptor referring to a map with a given ID. More...

int	bpf_map_get_next_id (__u32 start_id, __u32 *next_id)
	Look for the next map ID greater than a given ID. More...

int	bpf_map_get_next_key (int fd, const void key, void next_key)
	Look up an element by key in a map and get the next key. If the specific key is not found, the first key in the map is passed back. More...

int	bpf_map_lookup_elem (int fd, const void key, void value)
	Look up an element by key in a specified map and return its value. More...

int	bpf_map_update_elem (int fd, const void key, const void value, __u64 flags)
	Create or update an element (key/value pair) in a specified map. More...

Object-related functions
int	bpf_obj_get (const char *pathname)
	Get a file descriptor for a pinned object by pin path. More...

int	bpf_obj_get_info_by_fd (int bpf_fd, void info, __u32 info_len)
	Obtain information about the eBPF object referred to by bpf_fd. This function populates up to info_len bytes of info, which will be in one of the following formats depending on the eBPF object type of bpf_fd: More...

int	bpf_obj_pin (int fd, const char *pathname)
	Pin an eBPF program or map referred to by fd to the provided pathname. More...

Program-related functions
int	bpf_prog_bind_map (int prog_fd, int map_fd, const struct bpf_prog_bind_opts *opts)
	Bind a map to a program so that it holds a reference on the map. More...

int	bpf_prog_get_fd_by_id (__u32 id)
	Get a file descriptor referring to a program with a given ID. More...

int	bpf_prog_get_next_id (__u32 start_id, __u32 *next_id)
	Look for the next program ID greater than a given ID. More...

int	bpf_prog_load (enum bpf_prog_type prog_type, const char prog_name, const char license, const struct bpf_insn insns, size_t insn_cnt, const struct bpf_prog_load_opts opts)
	Load (but do not attach) an eBPF programs. More...

Function Documentation

◆ bpf_link_detach()

int bpf_link_detach ( int link_fd )

Detach a link.

Parameters

[in] link_fd File descriptor of link to detach.

Return values

0	The operation was successful.
<0	An error occured, and errno was set.

Exceptions

EBADF The file descriptor was not found.

See also: bpf_link__destroy; bpf_link__disconnect

◆ bpf_link_get_fd_by_id()

int bpf_link_get_fd_by_id ( __u32 id )

Get a file descriptor referring to a link with a given ID.

Parameters

[in] id ID of link to find.

Returns: A new file descriptor that refers to the link. The caller should call _close() on the fd to close this when done. A negative value indicates an error occurred and errno was set.

Exceptions

ENOENT No link with the specified ID was found.

◆ bpf_link_get_next_id()

int bpf_link_get_next_id	(	__u32	start_id,
		__u32 *	next_id
	)

Look for the next link ID greater than a given ID.

Parameters

[in]	start_id	ID to look for an ID after. The start_id need not exist.
[out]	next_id	Pointer to where to write the next ID.

Return values

0	The operation was successful.
<0	An error occured, and errno was set.

Exceptions

ENOENT No more IDs found.

◆ bpf_map_create()

int bpf_map_create	(	enum bpf_map_type	map_type,
		const char *	map_name,
		__u32	key_size,
		__u32	value_size,
		__u32	max_entries,
		const struct bpf_map_create_opts *	opts
	)

Create a new map.

Parameters

[in]	map_type	Type of outer map to create.
[in]	map_name	Optionally, the name to use for the map.
[in]	key_size	Size in bytes of keys.
[in]	value_size	Size in bytes of values.
[in]	max_entries	Maximum number of entries in the map.
[in]	opts	Structure of options using which a map gets created.

Returns: A new file descriptor that refers to the map. The caller should call _close() on the fd to close this when done. A negative value indicates an error occurred and errno was set.

Exceptions

EINVAL	An invalid argument was provided.
ENOMEM	Out of memory.

◆ bpf_map_delete_elem()

int bpf_map_delete_elem	(	int	fd,
		const void *	key
	)

Look up and delete an element by key in a specified map.

Parameters

[in]	fd	File descriptor of map to update.
[in]	key	Pointer to key to look up.

Return values

0	The operation was successful.
<0	An error occured, and errno was set.

Exceptions

EINVAL	An invalid argument was provided.
EBADF	The file descriptor was not found.
ENOMEM	Out of memory.

◆ bpf_map_get_fd_by_id()

int bpf_map_get_fd_by_id ( __u32 id )

Get a file descriptor referring to a map with a given ID.

Parameters

[in] id ID of map to find.

Returns: A new file descriptor that refers to the map. The caller should call _close() on the fd to close this when done. A negative value indicates an error occurred and errno was set.

Exceptions

ENOENT No map with the specified ID was found.

◆ bpf_map_get_next_id()

int bpf_map_get_next_id	(	__u32	start_id,
		__u32 *	next_id
	)

Look for the next map ID greater than a given ID.

Parameters

[in]	start_id	ID to look for an ID after. The start_id need not exist.
[out]	next_id	Pointer to where to write the next ID.

Return values

0	The operation was successful.
<0	An error occured, and errno was set.

Exceptions

ENOENT No more IDs found.

◆ bpf_map_get_next_key()

int bpf_map_get_next_key	(	int	fd,
		const void *	key,
		void *	next_key
	)

Look up an element by key in a map and get the next key. If the specific key is not found, the first key in the map is passed back.

Parameters

[in]	fd	File descriptor of map.
[in]	key	Pointer to key to look up.
[out]	next_key	Pointer to memory in which to write the next key.

Return values

0	The operation was successful.
<0	An error occured, and errno was set.

Exceptions

EINVAL	An invalid argument was provided.
EBADF	The file descriptor was not found.
ENOMEM	Out of memory.

◆ bpf_map_lookup_elem()

int bpf_map_lookup_elem	(	int	fd,
		const void *	key,
		void *	value
	)

Look up an element by key in a specified map and return its value.

Parameters

[in]	fd	File descriptor of map.
[in]	key	Pointer to key to look up.
[out]	value	Pointer to memory in which to write the value.

Return values

0	The operation was successful.
<0	An error occured, and errno was set.

Exceptions

EINVAL	An invalid argument was provided.
EBADF	The file descriptor was not found.
ENOMEM	Out of memory.

◆ bpf_map_update_elem()

int bpf_map_update_elem	(	int	fd,
		const void *	key,
		const void *	value,
		__u64	flags
	)

Create or update an element (key/value pair) in a specified map.

Parameters

[in]	fd	File descriptor of map.
[in]	key	Pointer to key.
[in]	value	Pointer to value.
[in]	flags	Flags (currently 0).

Exceptions

EINVAL	An invalid argument was provided.
EBADF	The file descriptor was not found.
ENOMEM	Out of memory.

◆ bpf_obj_get()

int bpf_obj_get ( const char * pathname )

Get a file descriptor for a pinned object by pin path.

Parameters

[in] pathname Pin path for the object.

Returns: A new file descriptor for the pinned object. The caller should call _close() on the fd to close this when done. A negative value indicates an error occurred and errno was set.

◆ bpf_obj_get_info_by_fd()

int bpf_obj_get_info_by_fd	(	int	bpf_fd,
		void *	info,
		__u32 *	info_len
	)

Obtain information about the eBPF object referred to by bpf_fd. This function populates up to info_len bytes of info, which will be in one of the following formats depending on the eBPF object type of bpf_fd:

Parameters

[in]	bpf_fd	File descriptor referring to an eBPF object.
[out]	info	Pointer to memory in which to write the info obtained.
[in,out]	info_len	On input, contains the maximum number of bytes to write into the info. On output, contains the actual number of bytes written.

Return values

0	The operation was successful.
-EFAULT	A pointer passed in the input info was invalid.
<0	An error occured, and errno was set.

◆ bpf_obj_pin()

int bpf_obj_pin	(	int	fd,
		const char *	pathname
	)

Pin an eBPF program or map referred to by fd to the provided pathname.

Parameters

[in]	fd	File descriptor referring to the program or map to pin.
[in]	pathname	Path name to pin the object to.

Return values

0	The operation was successful.
<0	An error occured, and errno was set.

◆ bpf_prog_bind_map()

int bpf_prog_bind_map	(	int	prog_fd,
		int	map_fd,
		const struct bpf_prog_bind_opts *	opts
	)

Bind a map to a program so that it holds a reference on the map.

Parameters

[in]	prog_fd	File descriptor of program to bind map to.
[in]	map_fd	File descriptor of map to bind.
[in]	opts	Optional set of options affecting the bind operation.

Return values

0	The operation was successful.
<0	An error occured, and errno was set.

◆ bpf_prog_get_fd_by_id()

int bpf_prog_get_fd_by_id ( __u32 id )

Get a file descriptor referring to a program with a given ID.

Parameters

[in] id ID of program to find.

Returns: A new file descriptor that refers to the program. The caller should call _close() on the fd to close this when done. A negative value indicates an error occurred and errno was set.

Exceptions

ENOENT No program with the specified ID was found.

◆ bpf_prog_get_next_id()

int bpf_prog_get_next_id	(	__u32	start_id,
		__u32 *	next_id
	)

Look for the next program ID greater than a given ID.

Parameters

[in]	start_id	ID to look for an ID after. The start_id need not exist.
[out]	next_id	Pointer to where to write the next ID.

Return values

0	The operation was successful.
<0	An error occured, and errno was set.

Exceptions

ENOENT No more IDs found.

◆ bpf_prog_load()

int bpf_prog_load	(	enum bpf_prog_type	prog_type,
		const char *	prog_name,
		const char *	license,
		const struct bpf_insn *	insns,
		size_t	insn_cnt,
		const struct bpf_prog_load_opts *	opts
	)

Load (but do not attach) an eBPF programs.

Parameters

[in]	prog_type	Program type to use for loading eBPF programs.
[in]	prog_name	Program name.
[in]	license	License string (unused).
[in]	insns	Array of eBPF instructions.
[in]	insn_cnt	Count of instructions in the array.
[in]	opts	Additional options, or NULL to use default options.

Returns: A new file descriptor that refers to the program. The caller should call _close() on the fd to close this when done. A negative value indicates an error occurred and errno was set.

Exceptions

EACCES	The program failed verification.
EINVAL	One or more parameters are incorrect.
ENOMEM	Out of memory.

See also: bpf_load_program; bpf_load_program_xattr; bpf_object__close; bpf_program__attach

Functions

Function Documentation

◆ bpf_link_detach()

◆ bpf_link_get_fd_by_id()

◆ bpf_link_get_next_id()

◆ bpf_map_create()

◆ bpf_map_delete_elem()

◆ bpf_map_get_fd_by_id()

◆ bpf_map_get_next_id()

◆ bpf_map_get_next_key()

◆ bpf_map_lookup_elem()

◆ bpf_map_update_elem()

◆ bpf_obj_get()

◆ bpf_obj_get_info_by_fd()

◆ bpf_obj_pin()

◆ bpf_prog_bind_map()

◆ bpf_prog_get_fd_by_id()

◆ bpf_prog_get_next_id()

◆ bpf_prog_load()