Two new libbpf APIs are added to support bpf_iter:
  - bpf_program__attach_iter
    Given a bpf program and additional parameters, which is
    none now, returns a bpf_link.
  - bpf_iter_create
    syscall level API to create a bpf iterator.

The macro BPF_SEQ_PRINTF are also introduced. The format
looks like:
  BPF_SEQ_PRINTF(seq, "task id %d\n", pid);

This macro can help bpf program writers with
nicer bpf_seq_printf syntax similar to the kernel one.
Signed-off-by: NYonghong Song <yhs@fb.com>
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>
Acked-by: NAndrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200509175917.2476936-1-yhs@fb.com

Use PT_REGS_RC instead of PT_REGS_RET to get ret correctly.

Fixes: df8ff353 ("libbpf: Merge selftests' bpf_trace_helpers.h into libbpf's bpf_tracing.h")
Signed-off-by: NWenbo Zhang <ethercflow@gmail.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
Acked-by: NAndrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200315083252.22274-1-ethercflow@gmail.com

Syscall raw tracepoints have struct pt_regs pointer as tracepoint's first
argument. After that, reading any of pt_regs fields requires bpf_probe_read(),
even for tp_btf programs. Due to that, PT_REGS_PARMx macros are not usable as
is. This patch adds CO-RE variants of those macros that use BPF_CORE_READ() to
read necessary fields. This provides relocatable architecture-agnostic pt_regs
field accesses.
Signed-off-by: NAndrii Nakryiko <andriin@fb.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
Acked-by: NMartin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20200313172336.1879637-4-andriin@fb.com

Move BPF_PROG, BPF_KPROBE, and BPF_KRETPROBE macro into libbpf's bpf_tracing.h
header to make it available for non-selftests users.
Signed-off-by: NAndrii Nakryiko <andriin@fb.com>
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200229231112.1240137-5-andriin@fb.com

Add detection of vmlinux.h to bpf_tracing.h header for PT_REGS macro.
Currently, BPF applications have to define __KERNEL__ symbol to use correct
definition of struct pt_regs on x86 arch. This is due to different field names
under internal kernel vs UAPI conditions. To make this more transparent for
users, detect vmlinux.h by checking __VMLINUX_H__ symbol.
Signed-off-by: NAndrii Nakryiko <andriin@fb.com>
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200229231112.1240137-3-andriin@fb.com

Move bpf_helpers.h, bpf_tracing.h, and bpf_endian.h into libbpf. Move
bpf_helper_defs.h generation into libbpf's Makefile. Ensure all those
headers are installed along the other libbpf headers. Also, adjust
selftests and samples include path to include libbpf now.
Signed-off-by: NAndrii Nakryiko <andriin@fb.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
Acked-by: NSong Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20191008175942.1769476-6-andriin@fb.com

Split-off PT_REGS-related helpers into bpf_tracing.h header. Adjust
selftests and samples to include it where necessary.
Signed-off-by: NAndrii Nakryiko <andriin@fb.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
Acked-by: NJohn Fastabend <john.fastabend@gmail.com>
Acked-by: NSong Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20191008175942.1769476-5-andriin@fb.com

To allow adding a variadic BPF_CORE_READ macro with slightly different
syntax and semantics, define CORE_READ in CO-RE reloc tests, which is
a thin wrapper around low-level bpf_core_read() macro, which in turn is
just a wrapper around bpf_probe_read().
Signed-off-by: NAndrii Nakryiko <andriin@fb.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
Acked-by: NJohn Fastabend <john.fastabend@gmail.com>
Acked-by: NSong Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20191008175942.1769476-4-andriin@fb.com

Split off few legacy things from bpf_helpers.h into separate
bpf_legacy.h file:
- load_{byte|half|word};
- remove extra inner_idx and numa_node fields from bpf_map_def and
  introduce bpf_map_def_legacy for use in samples;
- move BPF_ANNOTATE_KV_PAIR into bpf_legacy.h.

Adjust samples and selftests accordingly by either including
bpf_legacy.h and using bpf_map_def_legacy, or switching to BTF-defined
maps altogether.
Signed-off-by: NAndrii Nakryiko <andriin@fb.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
Acked-by: NJohn Fastabend <john.fastabend@gmail.com>
Acked-by: NSong Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20191008175942.1769476-3-andriin@fb.com

Having GCC provide its own bpf-helper.h is not the right approach and is
going to be changed. Undo bpf_helpers.h change before moving
bpf_helpers.h into libbpf.
Signed-off-by: NAndrii Nakryiko <andriin@fb.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
Acked-by: NSong Liu <songliubraving@fb.com>
Acked-by: NIlya Leoshkevich <iii@linux.ibm.com>
Acked-by: NJohn Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20191008175942.1769476-2-andriin@fb.com

Get rid of list of BPF helpers in bpf_helpers.h (irony...) and
auto-generate it into bpf_helpers_defs.h, which is now included from
bpf_helpers.h.
Suggested-by: NAlexei Starovoitov <ast@fb.com>
Signed-off-by: NAndrii Nakryiko <andriin@fb.com>
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>

Due to a quirky C syntax of declaring pointers to array or function
prototype, existing __type() macro doesn't work with map key/value types
that are array or function prototype. One has to create a typedef first
and use it to specify key/value type for a BPF map.  By using typeof(),
pointer to type is now handled uniformly for all kinds of types. Convert
one of self-tests as a demonstration.
Signed-off-by: NAndrii Nakryiko <andriin@fb.com>
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20191004040211.2434033-1-andriin@fb.com

Now that binutils and gcc support for BPF is upstream, make use of it in
BPF selftests using alu32-like approach. Share as much as possible of
CFLAGS calculation with clang.

Fixes only obvious issues, leaving more complex ones for later:
- Use gcc-provided bpf-helpers.h instead of manually defining the
  helpers, change bpf_helpers.h include guard to avoid conflict.
- Include <linux/stddef.h> for __always_inline.
- Add $(OUTPUT)/../usr/include to include path in order to use local
  kernel headers instead of system kernel headers when building with O=.

In order to activate the bpf-gcc support, one needs to configure
binutils and gcc with --target=bpf and make them available in $PATH. In
particular, gcc must be installed as `bpf-gcc`, which is the default.

Right now with binutils 25a2915e8dba and gcc r275589 only a handful of
tests work:

	# ./test_progs_bpf_gcc
	# Summary: 7/39 PASSED, 1 SKIPPED, 98 FAILED

The reason for those failures are as follows:

- Build errors:
  - `error: too many function arguments for eBPF` for __always_inline
    functions read_str_var and read_map_var - must be inlining issue,
    and for process_l3_headers_v6, which relies on optimizing away
    function arguments.
  - `error: indirect call in function, which are not supported by eBPF`
    where there are no obvious indirect calls in the source calls, e.g.
    in __encap_ipip_none.
  - `error: field 'lock' has incomplete type` for fields of `struct
    bpf_spin_lock` type - bpf_spin_lock is re#defined by bpf-helpers.h,
    so its usage is sensitive to order of #includes.
  - `error: eBPF stack limit exceeded` in sysctl_tcp_mem.
- Load errors:
  - Missing object files due to above build errors.
  - `libbpf: failed to create map (name: 'test_ver.bss')`.
  - `libbpf: object file doesn't contain bpf program`.
  - `libbpf: Program '.text' contains unrecognized relo data pointing to
    section 0`.
  - `libbpf: BTF is required, but is missing or corrupted` - no BTF
    support in gcc yet.
Signed-off-by: NIlya Leoshkevich <iii@linux.ibm.com>
Cc: Jose E. Marchesi <jose.marchesi@oracle.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>

bpf_helpers.h and bpf_endian.h contain useful macros and BPF helper
definitions essential to almost every BPF program. Which makes them
useful not just for selftests. To be able to expose them as part of
libbpf, though, we need them to be dual-licensed as LGPL-2.1 OR
BSD-2-Clause. This patch updates licensing of those two files.
Acked-by: NAlexei Starovoitov <ast@kernel.org>
Acked-by: NHechao Li <hechaol@fb.com>
Acked-by: NMartin KaFai Lau <kafai@fb.com>
Acked-by: NAndrey Ignatov <rdna@fb.com>
Acked-by: NYonghong Song <yhs@fb.com>
Acked-by: NLawrence Brakmo <brakmo@fb.com>
Acked-by: NAdam Barth <arb@fb.com>
Acked-by: NRoman Gushchin <guro@fb.com>
Acked-by: NJosef Bacik <jbacik@fb.com>
Acked-by: NJoe Stringer <joe@wand.net.nz>
Acked-by: NDaniel Borkmann <daniel@iogearbox.net>
Acked-by: NJoel Fernandes (Google) <joel@joelfernandes.org>
Acked-by: NDavid Ahern <dsahern@gmail.com>
Acked-by: NJesper Dangaard Brouer <brouer@redhat.com>
Acked-by: NIlya Leoshkevich <iii@linux.ibm.com>
Acked-by: NLorenz Bauer <lmb@cloudflare.com>
Acked-by: NAdrian Ratiu <adrian.ratiu@collabora.com>
Acked-by: NNikita V. Shirokov <tehnerd@tehnerd.com>
Acked-by: NWillem de Bruijn <willemb@google.com>
Acked-by: NPetar Penkov <ppenkov@google.com>
Acked-by: NTeng Qin <palmtenor@gmail.com>
Cc: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Cc: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Michal Rostecki <mrostecki@opensuse.org>
Cc: John Fastabend <john.fastabend@gmail.com>
Cc: Sargun Dhillon <sargun@sargun.me>
Signed-off-by: NAndrii Nakryiko <andriin@fb.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>

Add BPF_CORE_READ macro used in tests to do bpf_core_read(), which
automatically captures offset relocation.
Signed-off-by: NAndrii Nakryiko <andriin@fb.com>
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>

Expose bpf_tcp_gen_syncookie to selftests.
Signed-off-by: NPetar Penkov <ppenkov@google.com>
Reviewed-by: NLorenz Bauer <lmb@cloudflare.com>
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>

Right now, on certain architectures, these macros are usable only with
kernel headers. This patch makes it possible to use them with userspace
headers and, as a consequence, not only in BPF samples, but also in BPF
selftests.

On s390, provide the forward declaration of struct pt_regs and cast it
to user_pt_regs in PT_REGS_* macros. This is necessary, because instead
of the full struct pt_regs, s390 exposes only its first member
user_pt_regs to userspace, and bpf_helpers.h is used with both userspace
(in selftests) and kernel (in samples) headers. It was added in commit
466698e6 ("s390/bpf: correct broken uapi for
BPF_PROG_TYPE_PERF_EVENT program type").

Ditto on arm64.

On x86, provide userspace versions of PT_REGS_* macros. Unlike s390 and
arm64, x86 provides struct pt_regs to both userspace and kernel, however,
with different member names.
Signed-off-by: NIlya Leoshkevich <iii@linux.ibm.com>
Acked-by: NAndrii Nakryiko <andriin@fb.com>
Reviewed-by: NStanislav Fomichev <sdf@google.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>

Also check for __s390__ instead of __s390x__, just in case bpf_helpers.h
is ever used by 32-bit userspace.
Signed-off-by: NIlya Leoshkevich <iii@linux.ibm.com>
Acked-by: NAndrii Nakryiko <andriin@fb.com>
Reviewed-by: NStanislav Fomichev <sdf@google.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>

bpf_helpers.h fails to compile on sparc: the code should be checking
for defined(bpf_target_sparc), but checks simply for bpf_target_sparc.

Also change #ifdef bpf_target_powerpc to #if defined() for consistency.
Signed-off-by: NIlya Leoshkevich <iii@linux.ibm.com>
Acked-by: NAndrii Nakryiko <andriin@fb.com>
Acked-by: NDavid S. Miller <davem@davemloft.net>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>

Add simple __uint and __type macro that hide details of how type and
integer values are captured in BTF-defined maps.
Signed-off-by: NAndrii Nakryiko <andriin@fb.com>
Acked-by: NSong Liu <songliubraving@fb.com>
Acked-by: NYonghong Song <yhs@fb.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>

Fix signature of bpf_probe_read and bpf_probe_write_user to mark source
pointer as const. This causes warnings during compilation for
applications relying on those helpers.
Signed-off-by: NAndrii Nakryiko <andriin@fb.com>
Acked-by: NMartin KaFai Lau <kafai@fb.com>
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>

The test covered both nmi and tracepoint perf events.
  $ ./test_progs
  ...
  test_send_signal_tracepoint:PASS:tracepoint 0 nsec
  ...
  test_send_signal_common:PASS:tracepoint 0 nsec
  ...
  test_send_signal_common:PASS:perf_event 0 nsec
  ...
  test_send_signal:OK
Acked-by: NAndrii Nakryiko <andriin@fb.com>
Signed-off-by: NYonghong Song <yhs@fb.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>

bpf_printk is a macro which is commonly used to print out debug messages
in BPF programs and it was copied in many selftests and samples. Since
all of them include bpf_helpers.h, this change moves the macro there.
Signed-off-by: NMichal Rostecki <mrostecki@opensuse.org>
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>

Fix bpf_get_current_task() declaration.
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>
Acked-by: NAndrii Nakryiko <andriin@fb.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>

This patch rides on an existing BPF_PROG_TYPE_CGROUP_SKB test
(test_sock_fields.c) to do a TCP end-to-end test on the new
bpf_sk_storage_* helpers.
Signed-off-by: NMartin KaFai Lau <kafai@fb.com>
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>

Add bpf_sysctl_* and bpf_strtoX helpers to bpf_helpers.h.
Signed-off-by: NAndrey Ignatov <rdna@fb.com>
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>

Add tests for libbpf relocation of static variable references
into the .data, .rodata and .bss sections of the ELF, also add
read-only test for .rodata. All passing:

  # ./test_progs
  [...]
  test_global_data:PASS:load program 0 nsec
  test_global_data:PASS:pass global data run 925 nsec
  test_global_data_number:PASS:relocate .bss reference 925 nsec
  test_global_data_number:PASS:relocate .data reference 925 nsec
  test_global_data_number:PASS:relocate .rodata reference 925 nsec
  test_global_data_number:PASS:relocate .bss reference 925 nsec
  test_global_data_number:PASS:relocate .data reference 925 nsec
  test_global_data_number:PASS:relocate .rodata reference 925 nsec
  test_global_data_number:PASS:relocate .bss reference 925 nsec
  test_global_data_number:PASS:relocate .bss reference 925 nsec
  test_global_data_number:PASS:relocate .rodata reference 925 nsec
  test_global_data_number:PASS:relocate .rodata reference 925 nsec
  test_global_data_number:PASS:relocate .rodata reference 925 nsec
  test_global_data_string:PASS:relocate .rodata reference 925 nsec
  test_global_data_string:PASS:relocate .data reference 925 nsec
  test_global_data_string:PASS:relocate .bss reference 925 nsec
  test_global_data_string:PASS:relocate .data reference 925 nsec
  test_global_data_string:PASS:relocate .bss reference 925 nsec
  test_global_data_struct:PASS:relocate .rodata reference 925 nsec
  test_global_data_struct:PASS:relocate .bss reference 925 nsec
  test_global_data_struct:PASS:relocate .rodata reference 925 nsec
  test_global_data_struct:PASS:relocate .data reference 925 nsec
  test_global_data_rdonly:PASS:test .rodata read-only map 925 nsec
  [...]
  Summary: 229 PASSED, 0 FAILED

Note map helper signatures have been changed to avoid warnings
when passing in const data.

Joint work with Daniel Borkmann.
Signed-off-by: NJoe Stringer <joe@wand.net.nz>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
Acked-by: NAndrii Nakryiko <andriin@fb.com>
Acked-by: NMartin KaFai Lau <kafai@fb.com>
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>

Add tests which verify that the new helpers work for both IPv4 and
IPv6, by forcing SYN cookies to always on. Use a new network namespace
to avoid clobbering the global SYN cookie settings.
Signed-off-by: NLorenz Bauer <lmb@cloudflare.com>
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>

eBPF "restricted C" code can be compiled with LLVM/clang using target
triplets like armv7l-unknown-linux-gnueabihf and loaded/run with small
cross-compiled gobpf/elf [1] programs without requiring a full BCC
port which is also undesirable on small embedded systems due to its
size footprint. The only missing pieces are these helper macros which
otherwise have to be redefined by each eBPF arm program.

[1] https://github.com/iovisor/gobpf/tree/master/elfSigned-off-by: NAdrian Ratiu <adrian.ratiu@collabora.com>
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>

This patch adds an example in using the new helper
bpf_get_listener_sock().
Signed-off-by: NMartin KaFai Lau <kafai@fb.com>
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>

This patch syncs the uapi bpf.h to tools/ and also updates
bpf_herlpers.h in tools/
Signed-off-by: NLawrence Brakmo <brakmo@fb.com>
Acked-by: NSong Liu <songliubraving@fb.com>
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>

This header defines the BPF functions enumerated in uapi/linux.bpf.h
in a callable format. Expand to include all registered functions.
Signed-off-by: NWillem de Bruijn <willemb@google.com>
Acked-by: NSong Liu <songliubraving@fb.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>

This patch adds a C program to show the usage on
skb->sk and bpf_tcp_sock.
Acked-by: NAlexei Starovoitov <ast@kernel.org>
Signed-off-by: NMartin KaFai Lau <kafai@fb.com>
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>

add bpf_spin_lock C based test that requires latest llvm with BTF support
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>

Some IR remotes have a directional pad or other pointer-like thing that
can be used as a mouse. Make it possible to decode these types of IR
protocols in BPF.

Cc: netdev@vger.kernel.org
Signed-off-by: NSean Young <sean@mess.org>
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>

David Ahern and Nicolas Dichtel report that the handling of the netns id
0 is incorrect for the BPF socket lookup helpers: rather than finding
the netns with id 0, it is resolving to the current netns. This renders
the netns_id 0 inaccessible.

To fix this, adjust the API for the netns to treat all negative s32
values as a lookup in the current netns (including u64 values which when
truncated to s32 become negative), while any values with a positive
value in the signed 32-bit integer space would result in a lookup for a
socket in the netns corresponding to that id. As before, if the netns
with that ID does not exist, no socket will be found. Any netns outside
of these ranges will fail to find a corresponding socket, as those
values are reserved for future usage.
Signed-off-by: NJoe Stringer <joe@wand.net.nz>
Acked-by: NNicolas Dichtel <nicolas.dichtel@6wind.com>
Acked-by: NJoey Pabalinas <joeypabalinas@gmail.com>
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>

Add the necessary header definitions to tools for new
msg_pop_data_helper.
Signed-off-by: NJohn Fastabend <john.fastabend@gmail.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>

Add support for new bpf_msg_push_data in libbpf.
Signed-off-by: NJohn Fastabend <john.fastabend@gmail.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>

test_maps:
Tests that queue/stack maps are behaving correctly even in corner cases

test_progs:
Tests new ebpf helpers
Signed-off-by: NMauricio Vasquez B <mauricio.vasquez@polito.it>
Acked-by: NSong Liu <songliubraving@fb.com>
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>

The helper bpf_skb_vlan_push is needed by next patch, and the helper
bpf_skb_vlan_pop is added for completeness, regarding VLAN helpers.
Signed-off-by: NJesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>