1.. SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause)
2
3.. _program_types_and_elf:
4
5Program Types and ELF Sections
6==============================
7
8The table below lists the program types, their attach types where relevant and the ELF section
9names supported by libbpf for them. The ELF section names follow these rules:
10
11- ``type`` is an exact match, e.g. ``SEC("socket")``
12- ``type+`` means it can be either exact ``SEC("type")`` or well-formed ``SEC("type/extras")``
13  with a '``/``' separator between ``type`` and ``extras``.
14
15When ``extras`` are specified, they provide details of how to auto-attach the BPF program.  The
16format of ``extras`` depends on the program type, e.g. ``SEC("tracepoint/<category>/<name>")``
17for tracepoints or ``SEC("usdt/<path>:<provider>:<name>")`` for USDT probes. The extras are
18described in more detail in the footnotes.
19
20
21+-------------------------------------------+----------------------------------------+----------------------------------+-----------+
22| Program Type                              | Attach Type                            | ELF Section Name                 | Sleepable |
23+===========================================+========================================+==================================+===========+
24| ``BPF_PROG_TYPE_CGROUP_DEVICE``           | ``BPF_CGROUP_DEVICE``                  | ``cgroup/dev``                   |           |
25+-------------------------------------------+----------------------------------------+----------------------------------+-----------+
26| ``BPF_PROG_TYPE_CGROUP_SKB``              |                                        | ``cgroup/skb``                   |           |
27+                                           +----------------------------------------+----------------------------------+-----------+
28|                                           | ``BPF_CGROUP_INET_EGRESS``             | ``cgroup_skb/egress``            |           |
29+                                           +----------------------------------------+----------------------------------+-----------+
30|                                           | ``BPF_CGROUP_INET_INGRESS``            | ``cgroup_skb/ingress``           |           |
31+-------------------------------------------+----------------------------------------+----------------------------------+-----------+
32| ``BPF_PROG_TYPE_CGROUP_SOCKOPT``          | ``BPF_CGROUP_GETSOCKOPT``              | ``cgroup/getsockopt``            |           |
33+                                           +----------------------------------------+----------------------------------+-----------+
34|                                           | ``BPF_CGROUP_SETSOCKOPT``              | ``cgroup/setsockopt``            |           |
35+-------------------------------------------+----------------------------------------+----------------------------------+-----------+
36| ``BPF_PROG_TYPE_CGROUP_SOCK_ADDR``        | ``BPF_CGROUP_INET4_BIND``              | ``cgroup/bind4``                 |           |
37+                                           +----------------------------------------+----------------------------------+-----------+
38|                                           | ``BPF_CGROUP_INET4_CONNECT``           | ``cgroup/connect4``              |           |
39+                                           +----------------------------------------+----------------------------------+-----------+
40|                                           | ``BPF_CGROUP_INET4_GETPEERNAME``       | ``cgroup/getpeername4``          |           |
41+                                           +----------------------------------------+----------------------------------+-----------+
42|                                           | ``BPF_CGROUP_INET4_GETSOCKNAME``       | ``cgroup/getsockname4``          |           |
43+                                           +----------------------------------------+----------------------------------+-----------+
44|                                           | ``BPF_CGROUP_INET6_BIND``              | ``cgroup/bind6``                 |           |
45+                                           +----------------------------------------+----------------------------------+-----------+
46|                                           | ``BPF_CGROUP_INET6_CONNECT``           | ``cgroup/connect6``              |           |
47+                                           +----------------------------------------+----------------------------------+-----------+
48|                                           | ``BPF_CGROUP_INET6_GETPEERNAME``       | ``cgroup/getpeername6``          |           |
49+                                           +----------------------------------------+----------------------------------+-----------+
50|                                           | ``BPF_CGROUP_INET6_GETSOCKNAME``       | ``cgroup/getsockname6``          |           |
51+                                           +----------------------------------------+----------------------------------+-----------+
52|                                           | ``BPF_CGROUP_UDP4_RECVMSG``            | ``cgroup/recvmsg4``              |           |
53+                                           +----------------------------------------+----------------------------------+-----------+
54|                                           | ``BPF_CGROUP_UDP4_SENDMSG``            | ``cgroup/sendmsg4``              |           |
55+                                           +----------------------------------------+----------------------------------+-----------+
56|                                           | ``BPF_CGROUP_UDP6_RECVMSG``            | ``cgroup/recvmsg6``              |           |
57+                                           +----------------------------------------+----------------------------------+-----------+
58|                                           | ``BPF_CGROUP_UDP6_SENDMSG``            | ``cgroup/sendmsg6``              |           |
59|                                           +----------------------------------------+----------------------------------+-----------+
60|                                           | ``BPF_CGROUP_UNIX_CONNECT``            | ``cgroup/connect_unix``          |           |
61|                                           +----------------------------------------+----------------------------------+-----------+
62|                                           | ``BPF_CGROUP_UNIX_SENDMSG``            | ``cgroup/sendmsg_unix``          |           |
63|                                           +----------------------------------------+----------------------------------+-----------+
64|                                           | ``BPF_CGROUP_UNIX_RECVMSG``            | ``cgroup/recvmsg_unix``          |           |
65|                                           +----------------------------------------+----------------------------------+-----------+
66|                                           | ``BPF_CGROUP_UNIX_GETPEERNAME``        | ``cgroup/getpeername_unix``      |           |
67|                                           +----------------------------------------+----------------------------------+-----------+
68|                                           | ``BPF_CGROUP_UNIX_GETSOCKNAME``        | ``cgroup/getsockname_unix``      |           |
69+-------------------------------------------+----------------------------------------+----------------------------------+-----------+
70| ``BPF_PROG_TYPE_CGROUP_SOCK``             | ``BPF_CGROUP_INET4_POST_BIND``         | ``cgroup/post_bind4``            |           |
71+                                           +----------------------------------------+----------------------------------+-----------+
72|                                           | ``BPF_CGROUP_INET6_POST_BIND``         | ``cgroup/post_bind6``            |           |
73+                                           +----------------------------------------+----------------------------------+-----------+
74|                                           | ``BPF_CGROUP_INET_SOCK_CREATE``        | ``cgroup/sock_create``           |           |
75+                                           +                                        +----------------------------------+-----------+
76|                                           |                                        | ``cgroup/sock``                  |           |
77+                                           +----------------------------------------+----------------------------------+-----------+
78|                                           | ``BPF_CGROUP_INET_SOCK_RELEASE``       | ``cgroup/sock_release``          |           |
79+-------------------------------------------+----------------------------------------+----------------------------------+-----------+
80| ``BPF_PROG_TYPE_CGROUP_SYSCTL``           | ``BPF_CGROUP_SYSCTL``                  | ``cgroup/sysctl``                |           |
81+-------------------------------------------+----------------------------------------+----------------------------------+-----------+
82| ``BPF_PROG_TYPE_EXT``                     |                                        | ``freplace+`` [#fentry]_         |           |
83+-------------------------------------------+----------------------------------------+----------------------------------+-----------+
84| ``BPF_PROG_TYPE_FLOW_DISSECTOR``          | ``BPF_FLOW_DISSECTOR``                 | ``flow_dissector``               |           |
85+-------------------------------------------+----------------------------------------+----------------------------------+-----------+
86| ``BPF_PROG_TYPE_KPROBE``                  |                                        | ``kprobe+`` [#kprobe]_           |           |
87+                                           +                                        +----------------------------------+-----------+
88|                                           |                                        | ``kretprobe+`` [#kprobe]_        |           |
89+                                           +                                        +----------------------------------+-----------+
90|                                           |                                        | ``ksyscall+`` [#ksyscall]_       |           |
91+                                           +                                        +----------------------------------+-----------+
92|                                           |                                        |  ``kretsyscall+`` [#ksyscall]_   |           |
93+                                           +                                        +----------------------------------+-----------+
94|                                           |                                        | ``uprobe+`` [#uprobe]_           |           |
95+                                           +                                        +----------------------------------+-----------+
96|                                           |                                        | ``uprobe.s+`` [#uprobe]_         | Yes       |
97+                                           +                                        +----------------------------------+-----------+
98|                                           |                                        | ``uretprobe+`` [#uprobe]_        |           |
99+                                           +                                        +----------------------------------+-----------+
100|                                           |                                        | ``uretprobe.s+`` [#uprobe]_      | Yes       |
101+                                           +                                        +----------------------------------+-----------+
102|                                           |                                        | ``usdt+`` [#usdt]_               |           |
103+                                           +----------------------------------------+----------------------------------+-----------+
104|                                           | ``BPF_TRACE_KPROBE_MULTI``             | ``kprobe.multi+`` [#kpmulti]_    |           |
105+                                           +                                        +----------------------------------+-----------+
106|                                           |                                        | ``kretprobe.multi+`` [#kpmulti]_ |           |
107+-------------------------------------------+----------------------------------------+----------------------------------+-----------+
108| ``BPF_PROG_TYPE_LIRC_MODE2``              | ``BPF_LIRC_MODE2``                     | ``lirc_mode2``                   |           |
109+-------------------------------------------+----------------------------------------+----------------------------------+-----------+
110| ``BPF_PROG_TYPE_LSM``                     | ``BPF_LSM_CGROUP``                     | ``lsm_cgroup+``                  |           |
111+                                           +----------------------------------------+----------------------------------+-----------+
112|                                           | ``BPF_LSM_MAC``                        | ``lsm+`` [#lsm]_                 |           |
113+                                           +                                        +----------------------------------+-----------+
114|                                           |                                        | ``lsm.s+`` [#lsm]_               | Yes       |
115+-------------------------------------------+----------------------------------------+----------------------------------+-----------+
116| ``BPF_PROG_TYPE_LWT_IN``                  |                                        | ``lwt_in``                       |           |
117+-------------------------------------------+----------------------------------------+----------------------------------+-----------+
118| ``BPF_PROG_TYPE_LWT_OUT``                 |                                        | ``lwt_out``                      |           |
119+-------------------------------------------+----------------------------------------+----------------------------------+-----------+
120| ``BPF_PROG_TYPE_LWT_SEG6LOCAL``           |                                        | ``lwt_seg6local``                |           |
121+-------------------------------------------+----------------------------------------+----------------------------------+-----------+
122| ``BPF_PROG_TYPE_LWT_XMIT``                |                                        | ``lwt_xmit``                     |           |
123+-------------------------------------------+----------------------------------------+----------------------------------+-----------+
124| ``BPF_PROG_TYPE_NETFILTER``               |                                        | ``netfilter``                    |           |
125+-------------------------------------------+----------------------------------------+----------------------------------+-----------+
126| ``BPF_PROG_TYPE_PERF_EVENT``              |                                        | ``perf_event``                   |           |
127+-------------------------------------------+----------------------------------------+----------------------------------+-----------+
128| ``BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE`` |                                        | ``raw_tp.w+`` [#rawtp]_          |           |
129+                                           +                                        +----------------------------------+-----------+
130|                                           |                                        | ``raw_tracepoint.w+``            |           |
131+-------------------------------------------+----------------------------------------+----------------------------------+-----------+
132| ``BPF_PROG_TYPE_RAW_TRACEPOINT``          |                                        | ``raw_tp+`` [#rawtp]_            |           |
133+                                           +                                        +----------------------------------+-----------+
134|                                           |                                        | ``raw_tracepoint+``              |           |
135+-------------------------------------------+----------------------------------------+----------------------------------+-----------+
136| ``BPF_PROG_TYPE_SCHED_ACT``               |                                        | ``action`` [#tc_legacy]_         |           |
137+-------------------------------------------+----------------------------------------+----------------------------------+-----------+
138| ``BPF_PROG_TYPE_SCHED_CLS``               |                                        | ``classifier`` [#tc_legacy]_     |           |
139+                                           +                                        +----------------------------------+-----------+
140|                                           |                                        | ``tc`` [#tc_legacy]_             |           |
141+                                           +----------------------------------------+----------------------------------+-----------+
142|                                           | ``BPF_NETKIT_PRIMARY``                 | ``netkit/primary``               |           |
143+                                           +----------------------------------------+----------------------------------+-----------+
144|                                           | ``BPF_NETKIT_PEER``                    | ``netkit/peer``                  |           |
145+                                           +----------------------------------------+----------------------------------+-----------+
146|                                           | ``BPF_TCX_INGRESS``                    | ``tc/ingress``                   |           |
147+                                           +----------------------------------------+----------------------------------+-----------+
148|                                           | ``BPF_TCX_EGRESS``                     | ``tc/egress``                    |           |
149+                                           +----------------------------------------+----------------------------------+-----------+
150|                                           | ``BPF_TCX_INGRESS``                    | ``tcx/ingress``                  |           |
151+                                           +----------------------------------------+----------------------------------+-----------+
152|                                           | ``BPF_TCX_EGRESS``                     | ``tcx/egress``                   |           |
153+-------------------------------------------+----------------------------------------+----------------------------------+-----------+
154| ``BPF_PROG_TYPE_SK_LOOKUP``               | ``BPF_SK_LOOKUP``                      | ``sk_lookup``                    |           |
155+-------------------------------------------+----------------------------------------+----------------------------------+-----------+
156| ``BPF_PROG_TYPE_SK_MSG``                  | ``BPF_SK_MSG_VERDICT``                 | ``sk_msg``                       |           |
157+-------------------------------------------+----------------------------------------+----------------------------------+-----------+
158| ``BPF_PROG_TYPE_SK_REUSEPORT``            | ``BPF_SK_REUSEPORT_SELECT_OR_MIGRATE`` | ``sk_reuseport/migrate``         |           |
159+                                           +----------------------------------------+----------------------------------+-----------+
160|                                           | ``BPF_SK_REUSEPORT_SELECT``            | ``sk_reuseport``                 |           |
161+-------------------------------------------+----------------------------------------+----------------------------------+-----------+
162| ``BPF_PROG_TYPE_SK_SKB``                  |                                        | ``sk_skb``                       |           |
163+                                           +----------------------------------------+----------------------------------+-----------+
164|                                           | ``BPF_SK_SKB_STREAM_PARSER``           | ``sk_skb/stream_parser``         |           |
165+                                           +----------------------------------------+----------------------------------+-----------+
166|                                           | ``BPF_SK_SKB_STREAM_VERDICT``          | ``sk_skb/stream_verdict``        |           |
167+-------------------------------------------+----------------------------------------+----------------------------------+-----------+
168| ``BPF_PROG_TYPE_SOCKET_FILTER``           |                                        | ``socket``                       |           |
169+-------------------------------------------+----------------------------------------+----------------------------------+-----------+
170| ``BPF_PROG_TYPE_SOCK_OPS``                | ``BPF_CGROUP_SOCK_OPS``                | ``sockops``                      |           |
171+-------------------------------------------+----------------------------------------+----------------------------------+-----------+
172| ``BPF_PROG_TYPE_STRUCT_OPS``              |                                        | ``struct_ops+`` [#struct_ops]_   |           |
173+                                           +                                        +----------------------------------+-----------+
174|                                           |                                        | ``struct_ops.s+`` [#struct_ops]_ | Yes       |
175+-------------------------------------------+----------------------------------------+----------------------------------+-----------+
176| ``BPF_PROG_TYPE_SYSCALL``                 |                                        | ``syscall``                      | Yes       |
177+-------------------------------------------+----------------------------------------+----------------------------------+-----------+
178| ``BPF_PROG_TYPE_TRACEPOINT``              |                                        | ``tp+`` [#tp]_                   |           |
179+                                           +                                        +----------------------------------+-----------+
180|                                           |                                        | ``tracepoint+`` [#tp]_           |           |
181+-------------------------------------------+----------------------------------------+----------------------------------+-----------+
182| ``BPF_PROG_TYPE_TRACING``                 | ``BPF_MODIFY_RETURN``                  | ``fmod_ret+`` [#fentry]_         |           |
183+                                           +                                        +----------------------------------+-----------+
184|                                           |                                        | ``fmod_ret.s+`` [#fentry]_       | Yes       |
185+                                           +----------------------------------------+----------------------------------+-----------+
186|                                           | ``BPF_TRACE_FENTRY``                   | ``fentry+`` [#fentry]_           |           |
187+                                           +                                        +----------------------------------+-----------+
188|                                           |                                        | ``fentry.s+`` [#fentry]_         | Yes       |
189+                                           +----------------------------------------+----------------------------------+-----------+
190|                                           | ``BPF_TRACE_FEXIT``                    | ``fexit+`` [#fentry]_            |           |
191+                                           +                                        +----------------------------------+-----------+
192|                                           |                                        | ``fexit.s+`` [#fentry]_          | Yes       |
193+                                           +----------------------------------------+----------------------------------+-----------+
194|                                           | ``BPF_TRACE_ITER``                     | ``iter+`` [#iter]_               |           |
195+                                           +                                        +----------------------------------+-----------+
196|                                           |                                        | ``iter.s+`` [#iter]_             | Yes       |
197+                                           +----------------------------------------+----------------------------------+-----------+
198|                                           | ``BPF_TRACE_RAW_TP``                   | ``tp_btf+`` [#fentry]_           |           |
199+-------------------------------------------+----------------------------------------+----------------------------------+-----------+
200| ``BPF_PROG_TYPE_XDP``                     | ``BPF_XDP_CPUMAP``                     | ``xdp.frags/cpumap``             |           |
201+                                           +                                        +----------------------------------+-----------+
202|                                           |                                        | ``xdp/cpumap``                   |           |
203+                                           +----------------------------------------+----------------------------------+-----------+
204|                                           | ``BPF_XDP_DEVMAP``                     | ``xdp.frags/devmap``             |           |
205+                                           +                                        +----------------------------------+-----------+
206|                                           |                                        | ``xdp/devmap``                   |           |
207+                                           +----------------------------------------+----------------------------------+-----------+
208|                                           | ``BPF_XDP``                            | ``xdp.frags``                    |           |
209+                                           +                                        +----------------------------------+-----------+
210|                                           |                                        | ``xdp``                          |           |
211+-------------------------------------------+----------------------------------------+----------------------------------+-----------+
212
213
214.. rubric:: Footnotes
215
216.. [#fentry] The ``fentry`` attach format is ``fentry[.s]/<function>``.
217.. [#kprobe] The ``kprobe`` attach format is ``kprobe/<function>[+<offset>]``. Valid
218             characters for ``function`` are ``a-zA-Z0-9_.`` and ``offset`` must be a valid
219             non-negative integer.
220.. [#ksyscall] The ``ksyscall`` attach format is ``ksyscall/<syscall>``.
221.. [#uprobe] The ``uprobe`` attach format is ``uprobe[.s]/<path>:<function>[+<offset>]``.
222.. [#usdt] The ``usdt`` attach format is ``usdt/<path>:<provider>:<name>``.
223.. [#kpmulti] The ``kprobe.multi`` attach format is ``kprobe.multi/<pattern>`` where ``pattern``
224              supports ``*`` and ``?`` wildcards. Valid characters for pattern are
225              ``a-zA-Z0-9_.*?``.
226.. [#lsm] The ``lsm`` attachment format is ``lsm[.s]/<hook>``.
227.. [#rawtp] The ``raw_tp`` attach format is ``raw_tracepoint[.w]/<tracepoint>``.
228.. [#tc_legacy] The ``tc``, ``classifier`` and ``action`` attach types are deprecated, use
229                ``tcx/*`` instead.
230.. [#struct_ops] The ``struct_ops`` attach format supports ``struct_ops[.s]/<name>`` convention,
231                 but ``name`` is ignored and it is recommended to just use plain
232                 ``SEC("struct_ops[.s]")``. The attachments are defined in a struct initializer
233                 that is tagged with ``SEC(".struct_ops[.link]")``.
234.. [#tp] The ``tracepoint`` attach format is ``tracepoint/<category>/<name>``.
235.. [#iter] The ``iter`` attach format is ``iter[.s]/<struct-name>``.
236