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e2be04c7 | 1 | /* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */ |
daedfb22 AS |
2 | /* Copyright (c) 2011-2014 PLUMgrid, http://plumgrid.com |
3 | * | |
4 | * This program is free software; you can redistribute it and/or | |
5 | * modify it under the terms of version 2 of the GNU General Public | |
6 | * License as published by the Free Software Foundation. | |
7 | */ | |
8 | #ifndef _UAPI__LINUX_BPF_H__ | |
9 | #define _UAPI__LINUX_BPF_H__ | |
10 | ||
11 | #include <linux/types.h> | |
c15952dc | 12 | #include <linux/bpf_common.h> |
daedfb22 AS |
13 | |
14 | /* Extended instruction set based on top of classic BPF */ | |
15 | ||
16 | /* instruction classes */ | |
17 | #define BPF_ALU64 0x07 /* alu mode in double word width */ | |
18 | ||
19 | /* ld/ldx fields */ | |
cb5f7334 | 20 | #define BPF_DW 0x18 /* double word (64-bit) */ |
daedfb22 AS |
21 | #define BPF_XADD 0xc0 /* exclusive add */ |
22 | ||
23 | /* alu/jmp fields */ | |
24 | #define BPF_MOV 0xb0 /* mov reg to reg */ | |
25 | #define BPF_ARSH 0xc0 /* sign extending arithmetic shift right */ | |
26 | ||
27 | /* change endianness of a register */ | |
28 | #define BPF_END 0xd0 /* flags for endianness conversion: */ | |
29 | #define BPF_TO_LE 0x00 /* convert to little-endian */ | |
30 | #define BPF_TO_BE 0x08 /* convert to big-endian */ | |
31 | #define BPF_FROM_LE BPF_TO_LE | |
32 | #define BPF_FROM_BE BPF_TO_BE | |
33 | ||
92b31a9a | 34 | /* jmp encodings */ |
daedfb22 | 35 | #define BPF_JNE 0x50 /* jump != */ |
92b31a9a DB |
36 | #define BPF_JLT 0xa0 /* LT is unsigned, '<' */ |
37 | #define BPF_JLE 0xb0 /* LE is unsigned, '<=' */ | |
daedfb22 AS |
38 | #define BPF_JSGT 0x60 /* SGT is signed '>', GT in x86 */ |
39 | #define BPF_JSGE 0x70 /* SGE is signed '>=', GE in x86 */ | |
92b31a9a DB |
40 | #define BPF_JSLT 0xc0 /* SLT is signed, '<' */ |
41 | #define BPF_JSLE 0xd0 /* SLE is signed, '<=' */ | |
daedfb22 AS |
42 | #define BPF_CALL 0x80 /* function call */ |
43 | #define BPF_EXIT 0x90 /* function return */ | |
44 | ||
45 | /* Register numbers */ | |
46 | enum { | |
47 | BPF_REG_0 = 0, | |
48 | BPF_REG_1, | |
49 | BPF_REG_2, | |
50 | BPF_REG_3, | |
51 | BPF_REG_4, | |
52 | BPF_REG_5, | |
53 | BPF_REG_6, | |
54 | BPF_REG_7, | |
55 | BPF_REG_8, | |
56 | BPF_REG_9, | |
57 | BPF_REG_10, | |
58 | __MAX_BPF_REG, | |
59 | }; | |
60 | ||
61 | /* BPF has 10 general purpose 64-bit registers and stack frame. */ | |
62 | #define MAX_BPF_REG __MAX_BPF_REG | |
63 | ||
64 | struct bpf_insn { | |
65 | __u8 code; /* opcode */ | |
66 | __u8 dst_reg:4; /* dest register */ | |
67 | __u8 src_reg:4; /* source register */ | |
68 | __s16 off; /* signed offset */ | |
69 | __s32 imm; /* signed immediate constant */ | |
70 | }; | |
71 | ||
b95a5c4d DM |
72 | /* Key of an a BPF_MAP_TYPE_LPM_TRIE entry */ |
73 | struct bpf_lpm_trie_key { | |
74 | __u32 prefixlen; /* up to 32 for AF_INET, 128 for AF_INET6 */ | |
75 | __u8 data[0]; /* Arbitrary size */ | |
76 | }; | |
77 | ||
de9cbbaa RG |
78 | struct bpf_cgroup_storage_key { |
79 | __u64 cgroup_inode_id; /* cgroup inode id */ | |
80 | __u32 attach_type; /* program attach type */ | |
81 | }; | |
82 | ||
b2197755 | 83 | /* BPF syscall commands, see bpf(2) man-page for details. */ |
99c55f7d | 84 | enum bpf_cmd { |
99c55f7d | 85 | BPF_MAP_CREATE, |
db20fd2b | 86 | BPF_MAP_LOOKUP_ELEM, |
db20fd2b | 87 | BPF_MAP_UPDATE_ELEM, |
db20fd2b | 88 | BPF_MAP_DELETE_ELEM, |
db20fd2b | 89 | BPF_MAP_GET_NEXT_KEY, |
09756af4 | 90 | BPF_PROG_LOAD, |
b2197755 DB |
91 | BPF_OBJ_PIN, |
92 | BPF_OBJ_GET, | |
f4324551 DM |
93 | BPF_PROG_ATTACH, |
94 | BPF_PROG_DETACH, | |
1cf1cae9 | 95 | BPF_PROG_TEST_RUN, |
34ad5580 MKL |
96 | BPF_PROG_GET_NEXT_ID, |
97 | BPF_MAP_GET_NEXT_ID, | |
b16d9aa4 | 98 | BPF_PROG_GET_FD_BY_ID, |
bd5f5f4e | 99 | BPF_MAP_GET_FD_BY_ID, |
1e270976 | 100 | BPF_OBJ_GET_INFO_BY_FD, |
468e2f64 | 101 | BPF_PROG_QUERY, |
c4f6699d | 102 | BPF_RAW_TRACEPOINT_OPEN, |
f56a653c | 103 | BPF_BTF_LOAD, |
78958fca | 104 | BPF_BTF_GET_FD_BY_ID, |
41bdc4b4 | 105 | BPF_TASK_FD_QUERY, |
bd513cd0 | 106 | BPF_MAP_LOOKUP_AND_DELETE_ELEM, |
99c55f7d AS |
107 | }; |
108 | ||
109 | enum bpf_map_type { | |
110 | BPF_MAP_TYPE_UNSPEC, | |
0f8e4bd8 | 111 | BPF_MAP_TYPE_HASH, |
28fbcfa0 | 112 | BPF_MAP_TYPE_ARRAY, |
04fd61ab | 113 | BPF_MAP_TYPE_PROG_ARRAY, |
ea317b26 | 114 | BPF_MAP_TYPE_PERF_EVENT_ARRAY, |
824bd0ce | 115 | BPF_MAP_TYPE_PERCPU_HASH, |
a10423b8 | 116 | BPF_MAP_TYPE_PERCPU_ARRAY, |
d5a3b1f6 | 117 | BPF_MAP_TYPE_STACK_TRACE, |
4ed8ec52 | 118 | BPF_MAP_TYPE_CGROUP_ARRAY, |
29ba732a | 119 | BPF_MAP_TYPE_LRU_HASH, |
8f844938 | 120 | BPF_MAP_TYPE_LRU_PERCPU_HASH, |
b95a5c4d | 121 | BPF_MAP_TYPE_LPM_TRIE, |
56f668df | 122 | BPF_MAP_TYPE_ARRAY_OF_MAPS, |
bcc6b1b7 | 123 | BPF_MAP_TYPE_HASH_OF_MAPS, |
546ac1ff | 124 | BPF_MAP_TYPE_DEVMAP, |
174a79ff | 125 | BPF_MAP_TYPE_SOCKMAP, |
6710e112 | 126 | BPF_MAP_TYPE_CPUMAP, |
fbfc504a | 127 | BPF_MAP_TYPE_XSKMAP, |
81110384 | 128 | BPF_MAP_TYPE_SOCKHASH, |
de9cbbaa | 129 | BPF_MAP_TYPE_CGROUP_STORAGE, |
5dc4c4b7 | 130 | BPF_MAP_TYPE_REUSEPORT_SOCKARRAY, |
b741f163 | 131 | BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE, |
f1a2e44a MV |
132 | BPF_MAP_TYPE_QUEUE, |
133 | BPF_MAP_TYPE_STACK, | |
99c55f7d AS |
134 | }; |
135 | ||
09756af4 AS |
136 | enum bpf_prog_type { |
137 | BPF_PROG_TYPE_UNSPEC, | |
ddd872bc | 138 | BPF_PROG_TYPE_SOCKET_FILTER, |
2541517c | 139 | BPF_PROG_TYPE_KPROBE, |
96be4325 | 140 | BPF_PROG_TYPE_SCHED_CLS, |
94caee8c | 141 | BPF_PROG_TYPE_SCHED_ACT, |
98b5c2c6 | 142 | BPF_PROG_TYPE_TRACEPOINT, |
6a773a15 | 143 | BPF_PROG_TYPE_XDP, |
0515e599 | 144 | BPF_PROG_TYPE_PERF_EVENT, |
0e33661d | 145 | BPF_PROG_TYPE_CGROUP_SKB, |
61023658 | 146 | BPF_PROG_TYPE_CGROUP_SOCK, |
3a0af8fd TG |
147 | BPF_PROG_TYPE_LWT_IN, |
148 | BPF_PROG_TYPE_LWT_OUT, | |
149 | BPF_PROG_TYPE_LWT_XMIT, | |
40304b2a | 150 | BPF_PROG_TYPE_SOCK_OPS, |
b005fd18 | 151 | BPF_PROG_TYPE_SK_SKB, |
ebc614f6 | 152 | BPF_PROG_TYPE_CGROUP_DEVICE, |
4f738adb | 153 | BPF_PROG_TYPE_SK_MSG, |
c4f6699d | 154 | BPF_PROG_TYPE_RAW_TRACEPOINT, |
4fbac77d | 155 | BPF_PROG_TYPE_CGROUP_SOCK_ADDR, |
004d4b27 | 156 | BPF_PROG_TYPE_LWT_SEG6LOCAL, |
f4364dcf | 157 | BPF_PROG_TYPE_LIRC_MODE2, |
2dbb9b9e | 158 | BPF_PROG_TYPE_SK_REUSEPORT, |
d58e468b | 159 | BPF_PROG_TYPE_FLOW_DISSECTOR, |
09756af4 AS |
160 | }; |
161 | ||
0e33661d DM |
162 | enum bpf_attach_type { |
163 | BPF_CGROUP_INET_INGRESS, | |
164 | BPF_CGROUP_INET_EGRESS, | |
61023658 | 165 | BPF_CGROUP_INET_SOCK_CREATE, |
40304b2a | 166 | BPF_CGROUP_SOCK_OPS, |
464bc0fd JF |
167 | BPF_SK_SKB_STREAM_PARSER, |
168 | BPF_SK_SKB_STREAM_VERDICT, | |
ebc614f6 | 169 | BPF_CGROUP_DEVICE, |
4f738adb | 170 | BPF_SK_MSG_VERDICT, |
4fbac77d AI |
171 | BPF_CGROUP_INET4_BIND, |
172 | BPF_CGROUP_INET6_BIND, | |
d74bad4e AI |
173 | BPF_CGROUP_INET4_CONNECT, |
174 | BPF_CGROUP_INET6_CONNECT, | |
aac3fc32 AI |
175 | BPF_CGROUP_INET4_POST_BIND, |
176 | BPF_CGROUP_INET6_POST_BIND, | |
1cedee13 AI |
177 | BPF_CGROUP_UDP4_SENDMSG, |
178 | BPF_CGROUP_UDP6_SENDMSG, | |
f4364dcf | 179 | BPF_LIRC_MODE2, |
d58e468b | 180 | BPF_FLOW_DISSECTOR, |
0e33661d DM |
181 | __MAX_BPF_ATTACH_TYPE |
182 | }; | |
183 | ||
184 | #define MAX_BPF_ATTACH_TYPE __MAX_BPF_ATTACH_TYPE | |
185 | ||
324bda9e AS |
186 | /* cgroup-bpf attach flags used in BPF_PROG_ATTACH command |
187 | * | |
188 | * NONE(default): No further bpf programs allowed in the subtree. | |
189 | * | |
190 | * BPF_F_ALLOW_OVERRIDE: If a sub-cgroup installs some bpf program, | |
191 | * the program in this cgroup yields to sub-cgroup program. | |
192 | * | |
193 | * BPF_F_ALLOW_MULTI: If a sub-cgroup installs some bpf program, | |
194 | * that cgroup program gets run in addition to the program in this cgroup. | |
195 | * | |
196 | * Only one program is allowed to be attached to a cgroup with | |
197 | * NONE or BPF_F_ALLOW_OVERRIDE flag. | |
198 | * Attaching another program on top of NONE or BPF_F_ALLOW_OVERRIDE will | |
199 | * release old program and attach the new one. Attach flags has to match. | |
200 | * | |
201 | * Multiple programs are allowed to be attached to a cgroup with | |
202 | * BPF_F_ALLOW_MULTI flag. They are executed in FIFO order | |
203 | * (those that were attached first, run first) | |
204 | * The programs of sub-cgroup are executed first, then programs of | |
205 | * this cgroup and then programs of parent cgroup. | |
206 | * When children program makes decision (like picking TCP CA or sock bind) | |
207 | * parent program has a chance to override it. | |
208 | * | |
209 | * A cgroup with MULTI or OVERRIDE flag allows any attach flags in sub-cgroups. | |
210 | * A cgroup with NONE doesn't allow any programs in sub-cgroups. | |
211 | * Ex1: | |
212 | * cgrp1 (MULTI progs A, B) -> | |
213 | * cgrp2 (OVERRIDE prog C) -> | |
214 | * cgrp3 (MULTI prog D) -> | |
215 | * cgrp4 (OVERRIDE prog E) -> | |
216 | * cgrp5 (NONE prog F) | |
217 | * the event in cgrp5 triggers execution of F,D,A,B in that order. | |
218 | * if prog F is detached, the execution is E,D,A,B | |
219 | * if prog F and D are detached, the execution is E,A,B | |
220 | * if prog F, E and D are detached, the execution is C,A,B | |
221 | * | |
222 | * All eligible programs are executed regardless of return code from | |
223 | * earlier programs. | |
7f677633 AS |
224 | */ |
225 | #define BPF_F_ALLOW_OVERRIDE (1U << 0) | |
324bda9e | 226 | #define BPF_F_ALLOW_MULTI (1U << 1) |
7f677633 | 227 | |
e07b98d9 DM |
228 | /* If BPF_F_STRICT_ALIGNMENT is used in BPF_PROG_LOAD command, the |
229 | * verifier will perform strict alignment checking as if the kernel | |
230 | * has been built with CONFIG_EFFICIENT_UNALIGNED_ACCESS not set, | |
231 | * and NET_IP_ALIGN defined to 2. | |
232 | */ | |
233 | #define BPF_F_STRICT_ALIGNMENT (1U << 0) | |
234 | ||
cc8b0b92 | 235 | /* when bpf_ldimm64->src_reg == BPF_PSEUDO_MAP_FD, bpf_ldimm64->imm == fd */ |
f1a66f85 DB |
236 | #define BPF_PSEUDO_MAP_FD 1 |
237 | ||
cc8b0b92 AS |
238 | /* when bpf_call->src_reg == BPF_PSEUDO_CALL, bpf_call->imm == pc-relative |
239 | * offset to another bpf function | |
240 | */ | |
241 | #define BPF_PSEUDO_CALL 1 | |
242 | ||
3274f520 AS |
243 | /* flags for BPF_MAP_UPDATE_ELEM command */ |
244 | #define BPF_ANY 0 /* create new element or update existing */ | |
245 | #define BPF_NOEXIST 1 /* create new element if it didn't exist */ | |
246 | #define BPF_EXIST 2 /* update existing element */ | |
247 | ||
96eabe7a | 248 | /* flags for BPF_MAP_CREATE command */ |
6c905981 | 249 | #define BPF_F_NO_PREALLOC (1U << 0) |
29ba732a | 250 | /* Instead of having one common LRU list in the |
8f844938 | 251 | * BPF_MAP_TYPE_LRU_[PERCPU_]HASH map, use a percpu LRU list |
29ba732a MKL |
252 | * which can scale and perform better. |
253 | * Note, the LRU nodes (including free nodes) cannot be moved | |
254 | * across different LRU lists. | |
255 | */ | |
256 | #define BPF_F_NO_COMMON_LRU (1U << 1) | |
96eabe7a MKL |
257 | /* Specify numa node during map creation */ |
258 | #define BPF_F_NUMA_NODE (1U << 2) | |
6c905981 | 259 | |
468e2f64 AS |
260 | /* flags for BPF_PROG_QUERY */ |
261 | #define BPF_F_QUERY_EFFECTIVE (1U << 0) | |
262 | ||
cb4d2b3f MKL |
263 | #define BPF_OBJ_NAME_LEN 16U |
264 | ||
6e71b04a CF |
265 | /* Flags for accessing BPF object */ |
266 | #define BPF_F_RDONLY (1U << 3) | |
267 | #define BPF_F_WRONLY (1U << 4) | |
268 | ||
615755a7 SL |
269 | /* Flag for stack_map, store build_id+offset instead of pointer */ |
270 | #define BPF_F_STACK_BUILD_ID (1U << 5) | |
271 | ||
272 | enum bpf_stack_build_id_status { | |
273 | /* user space need an empty entry to identify end of a trace */ | |
274 | BPF_STACK_BUILD_ID_EMPTY = 0, | |
275 | /* with valid build_id and offset */ | |
276 | BPF_STACK_BUILD_ID_VALID = 1, | |
277 | /* couldn't get build_id, fallback to ip */ | |
278 | BPF_STACK_BUILD_ID_IP = 2, | |
279 | }; | |
280 | ||
281 | #define BPF_BUILD_ID_SIZE 20 | |
282 | struct bpf_stack_build_id { | |
283 | __s32 status; | |
284 | unsigned char build_id[BPF_BUILD_ID_SIZE]; | |
285 | union { | |
286 | __u64 offset; | |
287 | __u64 ip; | |
288 | }; | |
289 | }; | |
290 | ||
99c55f7d AS |
291 | union bpf_attr { |
292 | struct { /* anonymous struct used by BPF_MAP_CREATE command */ | |
293 | __u32 map_type; /* one of enum bpf_map_type */ | |
294 | __u32 key_size; /* size of key in bytes */ | |
295 | __u32 value_size; /* size of value in bytes */ | |
296 | __u32 max_entries; /* max number of entries in a map */ | |
96eabe7a MKL |
297 | __u32 map_flags; /* BPF_MAP_CREATE related |
298 | * flags defined above. | |
299 | */ | |
56f668df | 300 | __u32 inner_map_fd; /* fd pointing to the inner map */ |
96eabe7a MKL |
301 | __u32 numa_node; /* numa node (effective only if |
302 | * BPF_F_NUMA_NODE is set). | |
303 | */ | |
067cae47 | 304 | char map_name[BPF_OBJ_NAME_LEN]; |
a3884572 | 305 | __u32 map_ifindex; /* ifindex of netdev to create on */ |
a26ca7c9 | 306 | __u32 btf_fd; /* fd pointing to a BTF type data */ |
9b2cf328 MKL |
307 | __u32 btf_key_type_id; /* BTF type_id of the key */ |
308 | __u32 btf_value_type_id; /* BTF type_id of the value */ | |
99c55f7d | 309 | }; |
db20fd2b AS |
310 | |
311 | struct { /* anonymous struct used by BPF_MAP_*_ELEM commands */ | |
312 | __u32 map_fd; | |
313 | __aligned_u64 key; | |
314 | union { | |
315 | __aligned_u64 value; | |
316 | __aligned_u64 next_key; | |
317 | }; | |
3274f520 | 318 | __u64 flags; |
db20fd2b | 319 | }; |
09756af4 AS |
320 | |
321 | struct { /* anonymous struct used by BPF_PROG_LOAD command */ | |
322 | __u32 prog_type; /* one of enum bpf_prog_type */ | |
323 | __u32 insn_cnt; | |
324 | __aligned_u64 insns; | |
325 | __aligned_u64 license; | |
cbd35700 AS |
326 | __u32 log_level; /* verbosity level of verifier */ |
327 | __u32 log_size; /* size of user buffer */ | |
328 | __aligned_u64 log_buf; /* user supplied buffer */ | |
2541517c | 329 | __u32 kern_version; /* checked when prog_type=kprobe */ |
e07b98d9 | 330 | __u32 prog_flags; |
067cae47 | 331 | char prog_name[BPF_OBJ_NAME_LEN]; |
1f6f4cb7 | 332 | __u32 prog_ifindex; /* ifindex of netdev to prep for */ |
5e43f899 AI |
333 | /* For some prog types expected attach type must be known at |
334 | * load time to verify attach type specific parts of prog | |
335 | * (context accesses, allowed helpers, etc). | |
336 | */ | |
337 | __u32 expected_attach_type; | |
09756af4 | 338 | }; |
b2197755 DB |
339 | |
340 | struct { /* anonymous struct used by BPF_OBJ_* commands */ | |
341 | __aligned_u64 pathname; | |
342 | __u32 bpf_fd; | |
6e71b04a | 343 | __u32 file_flags; |
b2197755 | 344 | }; |
f4324551 DM |
345 | |
346 | struct { /* anonymous struct used by BPF_PROG_ATTACH/DETACH commands */ | |
347 | __u32 target_fd; /* container object to attach to */ | |
348 | __u32 attach_bpf_fd; /* eBPF program to attach */ | |
349 | __u32 attach_type; | |
7f677633 | 350 | __u32 attach_flags; |
f4324551 | 351 | }; |
1cf1cae9 AS |
352 | |
353 | struct { /* anonymous struct used by BPF_PROG_TEST_RUN command */ | |
354 | __u32 prog_fd; | |
355 | __u32 retval; | |
356 | __u32 data_size_in; | |
357 | __u32 data_size_out; | |
358 | __aligned_u64 data_in; | |
359 | __aligned_u64 data_out; | |
360 | __u32 repeat; | |
361 | __u32 duration; | |
362 | } test; | |
34ad5580 | 363 | |
b16d9aa4 MKL |
364 | struct { /* anonymous struct used by BPF_*_GET_*_ID */ |
365 | union { | |
366 | __u32 start_id; | |
367 | __u32 prog_id; | |
bd5f5f4e | 368 | __u32 map_id; |
78958fca | 369 | __u32 btf_id; |
b16d9aa4 | 370 | }; |
34ad5580 | 371 | __u32 next_id; |
6e71b04a | 372 | __u32 open_flags; |
34ad5580 | 373 | }; |
1e270976 MKL |
374 | |
375 | struct { /* anonymous struct used by BPF_OBJ_GET_INFO_BY_FD */ | |
376 | __u32 bpf_fd; | |
377 | __u32 info_len; | |
378 | __aligned_u64 info; | |
379 | } info; | |
468e2f64 AS |
380 | |
381 | struct { /* anonymous struct used by BPF_PROG_QUERY command */ | |
382 | __u32 target_fd; /* container object to query */ | |
383 | __u32 attach_type; | |
384 | __u32 query_flags; | |
385 | __u32 attach_flags; | |
386 | __aligned_u64 prog_ids; | |
387 | __u32 prog_cnt; | |
388 | } query; | |
c4f6699d AS |
389 | |
390 | struct { | |
391 | __u64 name; | |
392 | __u32 prog_fd; | |
393 | } raw_tracepoint; | |
f56a653c MKL |
394 | |
395 | struct { /* anonymous struct for BPF_BTF_LOAD */ | |
396 | __aligned_u64 btf; | |
397 | __aligned_u64 btf_log_buf; | |
398 | __u32 btf_size; | |
399 | __u32 btf_log_size; | |
400 | __u32 btf_log_level; | |
401 | }; | |
41bdc4b4 YS |
402 | |
403 | struct { | |
404 | __u32 pid; /* input: pid */ | |
405 | __u32 fd; /* input: fd */ | |
406 | __u32 flags; /* input: flags */ | |
407 | __u32 buf_len; /* input/output: buf len */ | |
408 | __aligned_u64 buf; /* input/output: | |
409 | * tp_name for tracepoint | |
410 | * symbol for kprobe | |
411 | * filename for uprobe | |
412 | */ | |
413 | __u32 prog_id; /* output: prod_id */ | |
414 | __u32 fd_type; /* output: BPF_FD_TYPE_* */ | |
415 | __u64 probe_offset; /* output: probe_offset */ | |
416 | __u64 probe_addr; /* output: probe_addr */ | |
417 | } task_fd_query; | |
99c55f7d AS |
418 | } __attribute__((aligned(8))); |
419 | ||
56a092c8 QM |
420 | /* The description below is an attempt at providing documentation to eBPF |
421 | * developers about the multiple available eBPF helper functions. It can be | |
422 | * parsed and used to produce a manual page. The workflow is the following, | |
423 | * and requires the rst2man utility: | |
424 | * | |
425 | * $ ./scripts/bpf_helpers_doc.py \ | |
426 | * --filename include/uapi/linux/bpf.h > /tmp/bpf-helpers.rst | |
427 | * $ rst2man /tmp/bpf-helpers.rst > /tmp/bpf-helpers.7 | |
428 | * $ man /tmp/bpf-helpers.7 | |
429 | * | |
430 | * Note that in order to produce this external documentation, some RST | |
431 | * formatting is used in the descriptions to get "bold" and "italics" in | |
432 | * manual pages. Also note that the few trailing white spaces are | |
433 | * intentional, removing them would break paragraphs for rst2man. | |
434 | * | |
435 | * Start of BPF helper function descriptions: | |
ad4a5223 QM |
436 | * |
437 | * void *bpf_map_lookup_elem(struct bpf_map *map, const void *key) | |
438 | * Description | |
439 | * Perform a lookup in *map* for an entry associated to *key*. | |
440 | * Return | |
441 | * Map value associated to *key*, or **NULL** if no entry was | |
442 | * found. | |
443 | * | |
444 | * int bpf_map_update_elem(struct bpf_map *map, const void *key, const void *value, u64 flags) | |
445 | * Description | |
446 | * Add or update the value of the entry associated to *key* in | |
447 | * *map* with *value*. *flags* is one of: | |
448 | * | |
449 | * **BPF_NOEXIST** | |
450 | * The entry for *key* must not exist in the map. | |
451 | * **BPF_EXIST** | |
452 | * The entry for *key* must already exist in the map. | |
453 | * **BPF_ANY** | |
454 | * No condition on the existence of the entry for *key*. | |
455 | * | |
456 | * Flag value **BPF_NOEXIST** cannot be used for maps of types | |
457 | * **BPF_MAP_TYPE_ARRAY** or **BPF_MAP_TYPE_PERCPU_ARRAY** (all | |
458 | * elements always exist), the helper would return an error. | |
459 | * Return | |
460 | * 0 on success, or a negative error in case of failure. | |
461 | * | |
462 | * int bpf_map_delete_elem(struct bpf_map *map, const void *key) | |
463 | * Description | |
464 | * Delete entry with *key* from *map*. | |
465 | * Return | |
466 | * 0 on success, or a negative error in case of failure. | |
467 | * | |
f1a2e44a MV |
468 | * int bpf_map_push_elem(struct bpf_map *map, const void *value, u64 flags) |
469 | * Description | |
470 | * Push an element *value* in *map*. *flags* is one of: | |
471 | * | |
472 | * **BPF_EXIST** | |
473 | * If the queue/stack is full, the oldest element is removed to | |
474 | * make room for this. | |
475 | * Return | |
476 | * 0 on success, or a negative error in case of failure. | |
477 | * | |
478 | * int bpf_map_pop_elem(struct bpf_map *map, void *value) | |
479 | * Description | |
480 | * Pop an element from *map*. | |
481 | * Return | |
482 | * 0 on success, or a negative error in case of failure. | |
483 | * | |
484 | * int bpf_map_peek_elem(struct bpf_map *map, void *value) | |
485 | * Description | |
486 | * Get an element from *map* without removing it. | |
487 | * Return | |
488 | * 0 on success, or a negative error in case of failure. | |
489 | * | |
ad4a5223 QM |
490 | * int bpf_probe_read(void *dst, u32 size, const void *src) |
491 | * Description | |
492 | * For tracing programs, safely attempt to read *size* bytes from | |
493 | * address *src* and store the data in *dst*. | |
494 | * Return | |
495 | * 0 on success, or a negative error in case of failure. | |
496 | * | |
497 | * u64 bpf_ktime_get_ns(void) | |
498 | * Description | |
499 | * Return the time elapsed since system boot, in nanoseconds. | |
500 | * Return | |
501 | * Current *ktime*. | |
502 | * | |
503 | * int bpf_trace_printk(const char *fmt, u32 fmt_size, ...) | |
504 | * Description | |
505 | * This helper is a "printk()-like" facility for debugging. It | |
506 | * prints a message defined by format *fmt* (of size *fmt_size*) | |
507 | * to file *\/sys/kernel/debug/tracing/trace* from DebugFS, if | |
508 | * available. It can take up to three additional **u64** | |
509 | * arguments (as an eBPF helpers, the total number of arguments is | |
510 | * limited to five). | |
511 | * | |
512 | * Each time the helper is called, it appends a line to the trace. | |
513 | * The format of the trace is customizable, and the exact output | |
514 | * one will get depends on the options set in | |
515 | * *\/sys/kernel/debug/tracing/trace_options* (see also the | |
516 | * *README* file under the same directory). However, it usually | |
517 | * defaults to something like: | |
518 | * | |
519 | * :: | |
520 | * | |
521 | * telnet-470 [001] .N.. 419421.045894: 0x00000001: <formatted msg> | |
522 | * | |
523 | * In the above: | |
524 | * | |
525 | * * ``telnet`` is the name of the current task. | |
526 | * * ``470`` is the PID of the current task. | |
527 | * * ``001`` is the CPU number on which the task is | |
528 | * running. | |
529 | * * In ``.N..``, each character refers to a set of | |
530 | * options (whether irqs are enabled, scheduling | |
531 | * options, whether hard/softirqs are running, level of | |
532 | * preempt_disabled respectively). **N** means that | |
533 | * **TIF_NEED_RESCHED** and **PREEMPT_NEED_RESCHED** | |
534 | * are set. | |
535 | * * ``419421.045894`` is a timestamp. | |
536 | * * ``0x00000001`` is a fake value used by BPF for the | |
537 | * instruction pointer register. | |
538 | * * ``<formatted msg>`` is the message formatted with | |
539 | * *fmt*. | |
540 | * | |
541 | * The conversion specifiers supported by *fmt* are similar, but | |
542 | * more limited than for printk(). They are **%d**, **%i**, | |
543 | * **%u**, **%x**, **%ld**, **%li**, **%lu**, **%lx**, **%lld**, | |
544 | * **%lli**, **%llu**, **%llx**, **%p**, **%s**. No modifier (size | |
545 | * of field, padding with zeroes, etc.) is available, and the | |
546 | * helper will return **-EINVAL** (but print nothing) if it | |
547 | * encounters an unknown specifier. | |
548 | * | |
549 | * Also, note that **bpf_trace_printk**\ () is slow, and should | |
550 | * only be used for debugging purposes. For this reason, a notice | |
551 | * bloc (spanning several lines) is printed to kernel logs and | |
552 | * states that the helper should not be used "for production use" | |
553 | * the first time this helper is used (or more precisely, when | |
554 | * **trace_printk**\ () buffers are allocated). For passing values | |
555 | * to user space, perf events should be preferred. | |
556 | * Return | |
557 | * The number of bytes written to the buffer, or a negative error | |
558 | * in case of failure. | |
559 | * | |
1fdd08be QM |
560 | * u32 bpf_get_prandom_u32(void) |
561 | * Description | |
562 | * Get a pseudo-random number. | |
563 | * | |
564 | * From a security point of view, this helper uses its own | |
565 | * pseudo-random internal state, and cannot be used to infer the | |
566 | * seed of other random functions in the kernel. However, it is | |
567 | * essential to note that the generator used by the helper is not | |
568 | * cryptographically secure. | |
569 | * Return | |
570 | * A random 32-bit unsigned value. | |
571 | * | |
572 | * u32 bpf_get_smp_processor_id(void) | |
573 | * Description | |
574 | * Get the SMP (symmetric multiprocessing) processor id. Note that | |
575 | * all programs run with preemption disabled, which means that the | |
576 | * SMP processor id is stable during all the execution of the | |
577 | * program. | |
578 | * Return | |
579 | * The SMP id of the processor running the program. | |
580 | * | |
ad4a5223 QM |
581 | * int bpf_skb_store_bytes(struct sk_buff *skb, u32 offset, const void *from, u32 len, u64 flags) |
582 | * Description | |
583 | * Store *len* bytes from address *from* into the packet | |
584 | * associated to *skb*, at *offset*. *flags* are a combination of | |
585 | * **BPF_F_RECOMPUTE_CSUM** (automatically recompute the | |
586 | * checksum for the packet after storing the bytes) and | |
587 | * **BPF_F_INVALIDATE_HASH** (set *skb*\ **->hash**, *skb*\ | |
588 | * **->swhash** and *skb*\ **->l4hash** to 0). | |
589 | * | |
590 | * A call to this helper is susceptible to change the underlaying | |
591 | * packet buffer. Therefore, at load time, all checks on pointers | |
592 | * previously done by the verifier are invalidated and must be | |
593 | * performed again, if the helper is used in combination with | |
594 | * direct packet access. | |
595 | * Return | |
596 | * 0 on success, or a negative error in case of failure. | |
597 | * | |
598 | * int bpf_l3_csum_replace(struct sk_buff *skb, u32 offset, u64 from, u64 to, u64 size) | |
599 | * Description | |
600 | * Recompute the layer 3 (e.g. IP) checksum for the packet | |
601 | * associated to *skb*. Computation is incremental, so the helper | |
602 | * must know the former value of the header field that was | |
603 | * modified (*from*), the new value of this field (*to*), and the | |
604 | * number of bytes (2 or 4) for this field, stored in *size*. | |
605 | * Alternatively, it is possible to store the difference between | |
606 | * the previous and the new values of the header field in *to*, by | |
607 | * setting *from* and *size* to 0. For both methods, *offset* | |
608 | * indicates the location of the IP checksum within the packet. | |
609 | * | |
610 | * This helper works in combination with **bpf_csum_diff**\ (), | |
611 | * which does not update the checksum in-place, but offers more | |
612 | * flexibility and can handle sizes larger than 2 or 4 for the | |
613 | * checksum to update. | |
614 | * | |
615 | * A call to this helper is susceptible to change the underlaying | |
616 | * packet buffer. Therefore, at load time, all checks on pointers | |
617 | * previously done by the verifier are invalidated and must be | |
618 | * performed again, if the helper is used in combination with | |
619 | * direct packet access. | |
620 | * Return | |
621 | * 0 on success, or a negative error in case of failure. | |
622 | * | |
623 | * int bpf_l4_csum_replace(struct sk_buff *skb, u32 offset, u64 from, u64 to, u64 flags) | |
624 | * Description | |
625 | * Recompute the layer 4 (e.g. TCP, UDP or ICMP) checksum for the | |
626 | * packet associated to *skb*. Computation is incremental, so the | |
627 | * helper must know the former value of the header field that was | |
628 | * modified (*from*), the new value of this field (*to*), and the | |
629 | * number of bytes (2 or 4) for this field, stored on the lowest | |
630 | * four bits of *flags*. Alternatively, it is possible to store | |
631 | * the difference between the previous and the new values of the | |
632 | * header field in *to*, by setting *from* and the four lowest | |
633 | * bits of *flags* to 0. For both methods, *offset* indicates the | |
634 | * location of the IP checksum within the packet. In addition to | |
635 | * the size of the field, *flags* can be added (bitwise OR) actual | |
636 | * flags. With **BPF_F_MARK_MANGLED_0**, a null checksum is left | |
637 | * untouched (unless **BPF_F_MARK_ENFORCE** is added as well), and | |
638 | * for updates resulting in a null checksum the value is set to | |
639 | * **CSUM_MANGLED_0** instead. Flag **BPF_F_PSEUDO_HDR** indicates | |
640 | * the checksum is to be computed against a pseudo-header. | |
641 | * | |
642 | * This helper works in combination with **bpf_csum_diff**\ (), | |
643 | * which does not update the checksum in-place, but offers more | |
644 | * flexibility and can handle sizes larger than 2 or 4 for the | |
645 | * checksum to update. | |
646 | * | |
647 | * A call to this helper is susceptible to change the underlaying | |
648 | * packet buffer. Therefore, at load time, all checks on pointers | |
649 | * previously done by the verifier are invalidated and must be | |
650 | * performed again, if the helper is used in combination with | |
651 | * direct packet access. | |
652 | * Return | |
653 | * 0 on success, or a negative error in case of failure. | |
654 | * | |
655 | * int bpf_tail_call(void *ctx, struct bpf_map *prog_array_map, u32 index) | |
656 | * Description | |
657 | * This special helper is used to trigger a "tail call", or in | |
658 | * other words, to jump into another eBPF program. The same stack | |
659 | * frame is used (but values on stack and in registers for the | |
660 | * caller are not accessible to the callee). This mechanism allows | |
661 | * for program chaining, either for raising the maximum number of | |
662 | * available eBPF instructions, or to execute given programs in | |
663 | * conditional blocks. For security reasons, there is an upper | |
664 | * limit to the number of successive tail calls that can be | |
665 | * performed. | |
666 | * | |
667 | * Upon call of this helper, the program attempts to jump into a | |
668 | * program referenced at index *index* in *prog_array_map*, a | |
669 | * special map of type **BPF_MAP_TYPE_PROG_ARRAY**, and passes | |
670 | * *ctx*, a pointer to the context. | |
671 | * | |
672 | * If the call succeeds, the kernel immediately runs the first | |
673 | * instruction of the new program. This is not a function call, | |
674 | * and it never returns to the previous program. If the call | |
675 | * fails, then the helper has no effect, and the caller continues | |
676 | * to run its subsequent instructions. A call can fail if the | |
677 | * destination program for the jump does not exist (i.e. *index* | |
678 | * is superior to the number of entries in *prog_array_map*), or | |
679 | * if the maximum number of tail calls has been reached for this | |
680 | * chain of programs. This limit is defined in the kernel by the | |
681 | * macro **MAX_TAIL_CALL_CNT** (not accessible to user space), | |
682 | * which is currently set to 32. | |
683 | * Return | |
684 | * 0 on success, or a negative error in case of failure. | |
685 | * | |
686 | * int bpf_clone_redirect(struct sk_buff *skb, u32 ifindex, u64 flags) | |
687 | * Description | |
688 | * Clone and redirect the packet associated to *skb* to another | |
689 | * net device of index *ifindex*. Both ingress and egress | |
690 | * interfaces can be used for redirection. The **BPF_F_INGRESS** | |
691 | * value in *flags* is used to make the distinction (ingress path | |
692 | * is selected if the flag is present, egress path otherwise). | |
693 | * This is the only flag supported for now. | |
694 | * | |
695 | * In comparison with **bpf_redirect**\ () helper, | |
696 | * **bpf_clone_redirect**\ () has the associated cost of | |
697 | * duplicating the packet buffer, but this can be executed out of | |
698 | * the eBPF program. Conversely, **bpf_redirect**\ () is more | |
699 | * efficient, but it is handled through an action code where the | |
700 | * redirection happens only after the eBPF program has returned. | |
701 | * | |
702 | * A call to this helper is susceptible to change the underlaying | |
703 | * packet buffer. Therefore, at load time, all checks on pointers | |
704 | * previously done by the verifier are invalidated and must be | |
705 | * performed again, if the helper is used in combination with | |
706 | * direct packet access. | |
707 | * Return | |
708 | * 0 on success, or a negative error in case of failure. | |
c456dec4 QM |
709 | * |
710 | * u64 bpf_get_current_pid_tgid(void) | |
711 | * Return | |
712 | * A 64-bit integer containing the current tgid and pid, and | |
713 | * created as such: | |
714 | * *current_task*\ **->tgid << 32 \|** | |
715 | * *current_task*\ **->pid**. | |
716 | * | |
717 | * u64 bpf_get_current_uid_gid(void) | |
718 | * Return | |
719 | * A 64-bit integer containing the current GID and UID, and | |
720 | * created as such: *current_gid* **<< 32 \|** *current_uid*. | |
721 | * | |
722 | * int bpf_get_current_comm(char *buf, u32 size_of_buf) | |
723 | * Description | |
724 | * Copy the **comm** attribute of the current task into *buf* of | |
725 | * *size_of_buf*. The **comm** attribute contains the name of | |
726 | * the executable (excluding the path) for the current task. The | |
727 | * *size_of_buf* must be strictly positive. On success, the | |
728 | * helper makes sure that the *buf* is NUL-terminated. On failure, | |
729 | * it is filled with zeroes. | |
730 | * Return | |
731 | * 0 on success, or a negative error in case of failure. | |
732 | * | |
1fdd08be QM |
733 | * u32 bpf_get_cgroup_classid(struct sk_buff *skb) |
734 | * Description | |
735 | * Retrieve the classid for the current task, i.e. for the net_cls | |
736 | * cgroup to which *skb* belongs. | |
737 | * | |
738 | * This helper can be used on TC egress path, but not on ingress. | |
739 | * | |
740 | * The net_cls cgroup provides an interface to tag network packets | |
741 | * based on a user-provided identifier for all traffic coming from | |
742 | * the tasks belonging to the related cgroup. See also the related | |
743 | * kernel documentation, available from the Linux sources in file | |
744 | * *Documentation/cgroup-v1/net_cls.txt*. | |
745 | * | |
746 | * The Linux kernel has two versions for cgroups: there are | |
747 | * cgroups v1 and cgroups v2. Both are available to users, who can | |
748 | * use a mixture of them, but note that the net_cls cgroup is for | |
749 | * cgroup v1 only. This makes it incompatible with BPF programs | |
750 | * run on cgroups, which is a cgroup-v2-only feature (a socket can | |
751 | * only hold data for one version of cgroups at a time). | |
752 | * | |
753 | * This helper is only available is the kernel was compiled with | |
754 | * the **CONFIG_CGROUP_NET_CLASSID** configuration option set to | |
755 | * "**y**" or to "**m**". | |
756 | * Return | |
757 | * The classid, or 0 for the default unconfigured classid. | |
758 | * | |
c456dec4 QM |
759 | * int bpf_skb_vlan_push(struct sk_buff *skb, __be16 vlan_proto, u16 vlan_tci) |
760 | * Description | |
761 | * Push a *vlan_tci* (VLAN tag control information) of protocol | |
762 | * *vlan_proto* to the packet associated to *skb*, then update | |
763 | * the checksum. Note that if *vlan_proto* is different from | |
764 | * **ETH_P_8021Q** and **ETH_P_8021AD**, it is considered to | |
765 | * be **ETH_P_8021Q**. | |
766 | * | |
767 | * A call to this helper is susceptible to change the underlaying | |
768 | * packet buffer. Therefore, at load time, all checks on pointers | |
769 | * previously done by the verifier are invalidated and must be | |
770 | * performed again, if the helper is used in combination with | |
771 | * direct packet access. | |
772 | * Return | |
773 | * 0 on success, or a negative error in case of failure. | |
774 | * | |
775 | * int bpf_skb_vlan_pop(struct sk_buff *skb) | |
776 | * Description | |
777 | * Pop a VLAN header from the packet associated to *skb*. | |
778 | * | |
779 | * A call to this helper is susceptible to change the underlaying | |
780 | * packet buffer. Therefore, at load time, all checks on pointers | |
781 | * previously done by the verifier are invalidated and must be | |
782 | * performed again, if the helper is used in combination with | |
783 | * direct packet access. | |
784 | * Return | |
785 | * 0 on success, or a negative error in case of failure. | |
786 | * | |
787 | * int bpf_skb_get_tunnel_key(struct sk_buff *skb, struct bpf_tunnel_key *key, u32 size, u64 flags) | |
788 | * Description | |
789 | * Get tunnel metadata. This helper takes a pointer *key* to an | |
790 | * empty **struct bpf_tunnel_key** of **size**, that will be | |
791 | * filled with tunnel metadata for the packet associated to *skb*. | |
792 | * The *flags* can be set to **BPF_F_TUNINFO_IPV6**, which | |
793 | * indicates that the tunnel is based on IPv6 protocol instead of | |
794 | * IPv4. | |
795 | * | |
796 | * The **struct bpf_tunnel_key** is an object that generalizes the | |
797 | * principal parameters used by various tunneling protocols into a | |
798 | * single struct. This way, it can be used to easily make a | |
799 | * decision based on the contents of the encapsulation header, | |
800 | * "summarized" in this struct. In particular, it holds the IP | |
801 | * address of the remote end (IPv4 or IPv6, depending on the case) | |
802 | * in *key*\ **->remote_ipv4** or *key*\ **->remote_ipv6**. Also, | |
803 | * this struct exposes the *key*\ **->tunnel_id**, which is | |
804 | * generally mapped to a VNI (Virtual Network Identifier), making | |
805 | * it programmable together with the **bpf_skb_set_tunnel_key**\ | |
806 | * () helper. | |
807 | * | |
808 | * Let's imagine that the following code is part of a program | |
809 | * attached to the TC ingress interface, on one end of a GRE | |
810 | * tunnel, and is supposed to filter out all messages coming from | |
811 | * remote ends with IPv4 address other than 10.0.0.1: | |
812 | * | |
813 | * :: | |
814 | * | |
815 | * int ret; | |
816 | * struct bpf_tunnel_key key = {}; | |
817 | * | |
818 | * ret = bpf_skb_get_tunnel_key(skb, &key, sizeof(key), 0); | |
819 | * if (ret < 0) | |
820 | * return TC_ACT_SHOT; // drop packet | |
821 | * | |
822 | * if (key.remote_ipv4 != 0x0a000001) | |
823 | * return TC_ACT_SHOT; // drop packet | |
824 | * | |
825 | * return TC_ACT_OK; // accept packet | |
826 | * | |
827 | * This interface can also be used with all encapsulation devices | |
828 | * that can operate in "collect metadata" mode: instead of having | |
829 | * one network device per specific configuration, the "collect | |
830 | * metadata" mode only requires a single device where the | |
831 | * configuration can be extracted from this helper. | |
832 | * | |
833 | * This can be used together with various tunnels such as VXLan, | |
834 | * Geneve, GRE or IP in IP (IPIP). | |
835 | * Return | |
836 | * 0 on success, or a negative error in case of failure. | |
837 | * | |
838 | * int bpf_skb_set_tunnel_key(struct sk_buff *skb, struct bpf_tunnel_key *key, u32 size, u64 flags) | |
839 | * Description | |
840 | * Populate tunnel metadata for packet associated to *skb.* The | |
841 | * tunnel metadata is set to the contents of *key*, of *size*. The | |
842 | * *flags* can be set to a combination of the following values: | |
843 | * | |
844 | * **BPF_F_TUNINFO_IPV6** | |
845 | * Indicate that the tunnel is based on IPv6 protocol | |
846 | * instead of IPv4. | |
847 | * **BPF_F_ZERO_CSUM_TX** | |
848 | * For IPv4 packets, add a flag to tunnel metadata | |
849 | * indicating that checksum computation should be skipped | |
850 | * and checksum set to zeroes. | |
851 | * **BPF_F_DONT_FRAGMENT** | |
852 | * Add a flag to tunnel metadata indicating that the | |
853 | * packet should not be fragmented. | |
854 | * **BPF_F_SEQ_NUMBER** | |
855 | * Add a flag to tunnel metadata indicating that a | |
856 | * sequence number should be added to tunnel header before | |
857 | * sending the packet. This flag was added for GRE | |
858 | * encapsulation, but might be used with other protocols | |
859 | * as well in the future. | |
860 | * | |
861 | * Here is a typical usage on the transmit path: | |
862 | * | |
863 | * :: | |
864 | * | |
865 | * struct bpf_tunnel_key key; | |
866 | * populate key ... | |
867 | * bpf_skb_set_tunnel_key(skb, &key, sizeof(key), 0); | |
868 | * bpf_clone_redirect(skb, vxlan_dev_ifindex, 0); | |
869 | * | |
870 | * See also the description of the **bpf_skb_get_tunnel_key**\ () | |
871 | * helper for additional information. | |
872 | * Return | |
873 | * 0 on success, or a negative error in case of failure. | |
874 | * | |
c6b5fb86 QM |
875 | * u64 bpf_perf_event_read(struct bpf_map *map, u64 flags) |
876 | * Description | |
877 | * Read the value of a perf event counter. This helper relies on a | |
878 | * *map* of type **BPF_MAP_TYPE_PERF_EVENT_ARRAY**. The nature of | |
879 | * the perf event counter is selected when *map* is updated with | |
880 | * perf event file descriptors. The *map* is an array whose size | |
881 | * is the number of available CPUs, and each cell contains a value | |
882 | * relative to one CPU. The value to retrieve is indicated by | |
883 | * *flags*, that contains the index of the CPU to look up, masked | |
884 | * with **BPF_F_INDEX_MASK**. Alternatively, *flags* can be set to | |
885 | * **BPF_F_CURRENT_CPU** to indicate that the value for the | |
886 | * current CPU should be retrieved. | |
887 | * | |
888 | * Note that before Linux 4.13, only hardware perf event can be | |
889 | * retrieved. | |
890 | * | |
891 | * Also, be aware that the newer helper | |
892 | * **bpf_perf_event_read_value**\ () is recommended over | |
3bd5a09b | 893 | * **bpf_perf_event_read**\ () in general. The latter has some ABI |
c6b5fb86 QM |
894 | * quirks where error and counter value are used as a return code |
895 | * (which is wrong to do since ranges may overlap). This issue is | |
3bd5a09b QM |
896 | * fixed with **bpf_perf_event_read_value**\ (), which at the same |
897 | * time provides more features over the **bpf_perf_event_read**\ | |
898 | * () interface. Please refer to the description of | |
c6b5fb86 QM |
899 | * **bpf_perf_event_read_value**\ () for details. |
900 | * Return | |
901 | * The value of the perf event counter read from the map, or a | |
902 | * negative error code in case of failure. | |
903 | * | |
c456dec4 QM |
904 | * int bpf_redirect(u32 ifindex, u64 flags) |
905 | * Description | |
906 | * Redirect the packet to another net device of index *ifindex*. | |
907 | * This helper is somewhat similar to **bpf_clone_redirect**\ | |
908 | * (), except that the packet is not cloned, which provides | |
909 | * increased performance. | |
910 | * | |
911 | * Except for XDP, both ingress and egress interfaces can be used | |
912 | * for redirection. The **BPF_F_INGRESS** value in *flags* is used | |
913 | * to make the distinction (ingress path is selected if the flag | |
914 | * is present, egress path otherwise). Currently, XDP only | |
915 | * supports redirection to the egress interface, and accepts no | |
916 | * flag at all. | |
917 | * | |
918 | * The same effect can be attained with the more generic | |
919 | * **bpf_redirect_map**\ (), which requires specific maps to be | |
920 | * used but offers better performance. | |
921 | * Return | |
922 | * For XDP, the helper returns **XDP_REDIRECT** on success or | |
923 | * **XDP_ABORTED** on error. For other program types, the values | |
924 | * are **TC_ACT_REDIRECT** on success or **TC_ACT_SHOT** on | |
925 | * error. | |
926 | * | |
1fdd08be QM |
927 | * u32 bpf_get_route_realm(struct sk_buff *skb) |
928 | * Description | |
929 | * Retrieve the realm or the route, that is to say the | |
930 | * **tclassid** field of the destination for the *skb*. The | |
931 | * indentifier retrieved is a user-provided tag, similar to the | |
932 | * one used with the net_cls cgroup (see description for | |
933 | * **bpf_get_cgroup_classid**\ () helper), but here this tag is | |
934 | * held by a route (a destination entry), not by a task. | |
935 | * | |
936 | * Retrieving this identifier works with the clsact TC egress hook | |
937 | * (see also **tc-bpf(8)**), or alternatively on conventional | |
938 | * classful egress qdiscs, but not on TC ingress path. In case of | |
939 | * clsact TC egress hook, this has the advantage that, internally, | |
940 | * the destination entry has not been dropped yet in the transmit | |
941 | * path. Therefore, the destination entry does not need to be | |
942 | * artificially held via **netif_keep_dst**\ () for a classful | |
943 | * qdisc until the *skb* is freed. | |
944 | * | |
945 | * This helper is available only if the kernel was compiled with | |
946 | * **CONFIG_IP_ROUTE_CLASSID** configuration option. | |
947 | * Return | |
948 | * The realm of the route for the packet associated to *skb*, or 0 | |
949 | * if none was found. | |
950 | * | |
c456dec4 QM |
951 | * int bpf_perf_event_output(struct pt_reg *ctx, struct bpf_map *map, u64 flags, void *data, u64 size) |
952 | * Description | |
953 | * Write raw *data* blob into a special BPF perf event held by | |
954 | * *map* of type **BPF_MAP_TYPE_PERF_EVENT_ARRAY**. This perf | |
955 | * event must have the following attributes: **PERF_SAMPLE_RAW** | |
956 | * as **sample_type**, **PERF_TYPE_SOFTWARE** as **type**, and | |
957 | * **PERF_COUNT_SW_BPF_OUTPUT** as **config**. | |
958 | * | |
959 | * The *flags* are used to indicate the index in *map* for which | |
960 | * the value must be put, masked with **BPF_F_INDEX_MASK**. | |
961 | * Alternatively, *flags* can be set to **BPF_F_CURRENT_CPU** | |
962 | * to indicate that the index of the current CPU core should be | |
963 | * used. | |
964 | * | |
965 | * The value to write, of *size*, is passed through eBPF stack and | |
966 | * pointed by *data*. | |
967 | * | |
968 | * The context of the program *ctx* needs also be passed to the | |
969 | * helper. | |
970 | * | |
971 | * On user space, a program willing to read the values needs to | |
972 | * call **perf_event_open**\ () on the perf event (either for | |
973 | * one or for all CPUs) and to store the file descriptor into the | |
974 | * *map*. This must be done before the eBPF program can send data | |
975 | * into it. An example is available in file | |
976 | * *samples/bpf/trace_output_user.c* in the Linux kernel source | |
977 | * tree (the eBPF program counterpart is in | |
978 | * *samples/bpf/trace_output_kern.c*). | |
979 | * | |
980 | * **bpf_perf_event_output**\ () achieves better performance | |
981 | * than **bpf_trace_printk**\ () for sharing data with user | |
982 | * space, and is much better suitable for streaming data from eBPF | |
983 | * programs. | |
984 | * | |
985 | * Note that this helper is not restricted to tracing use cases | |
986 | * and can be used with programs attached to TC or XDP as well, | |
987 | * where it allows for passing data to user space listeners. Data | |
988 | * can be: | |
989 | * | |
990 | * * Only custom structs, | |
991 | * * Only the packet payload, or | |
992 | * * A combination of both. | |
993 | * Return | |
994 | * 0 on success, or a negative error in case of failure. | |
995 | * | |
1fdd08be QM |
996 | * int bpf_skb_load_bytes(const struct sk_buff *skb, u32 offset, void *to, u32 len) |
997 | * Description | |
998 | * This helper was provided as an easy way to load data from a | |
999 | * packet. It can be used to load *len* bytes from *offset* from | |
1000 | * the packet associated to *skb*, into the buffer pointed by | |
1001 | * *to*. | |
1002 | * | |
1003 | * Since Linux 4.7, usage of this helper has mostly been replaced | |
1004 | * by "direct packet access", enabling packet data to be | |
1005 | * manipulated with *skb*\ **->data** and *skb*\ **->data_end** | |
1006 | * pointing respectively to the first byte of packet data and to | |
1007 | * the byte after the last byte of packet data. However, it | |
1008 | * remains useful if one wishes to read large quantities of data | |
1009 | * at once from a packet into the eBPF stack. | |
1010 | * Return | |
1011 | * 0 on success, or a negative error in case of failure. | |
1012 | * | |
c456dec4 QM |
1013 | * int bpf_get_stackid(struct pt_reg *ctx, struct bpf_map *map, u64 flags) |
1014 | * Description | |
1015 | * Walk a user or a kernel stack and return its id. To achieve | |
1016 | * this, the helper needs *ctx*, which is a pointer to the context | |
1017 | * on which the tracing program is executed, and a pointer to a | |
1018 | * *map* of type **BPF_MAP_TYPE_STACK_TRACE**. | |
1019 | * | |
1020 | * The last argument, *flags*, holds the number of stack frames to | |
1021 | * skip (from 0 to 255), masked with | |
1022 | * **BPF_F_SKIP_FIELD_MASK**. The next bits can be used to set | |
1023 | * a combination of the following flags: | |
1024 | * | |
1025 | * **BPF_F_USER_STACK** | |
1026 | * Collect a user space stack instead of a kernel stack. | |
1027 | * **BPF_F_FAST_STACK_CMP** | |
1028 | * Compare stacks by hash only. | |
1029 | * **BPF_F_REUSE_STACKID** | |
1030 | * If two different stacks hash into the same *stackid*, | |
1031 | * discard the old one. | |
1032 | * | |
1033 | * The stack id retrieved is a 32 bit long integer handle which | |
1034 | * can be further combined with other data (including other stack | |
1035 | * ids) and used as a key into maps. This can be useful for | |
1036 | * generating a variety of graphs (such as flame graphs or off-cpu | |
1037 | * graphs). | |
1038 | * | |
1039 | * For walking a stack, this helper is an improvement over | |
1040 | * **bpf_probe_read**\ (), which can be used with unrolled loops | |
1041 | * but is not efficient and consumes a lot of eBPF instructions. | |
1042 | * Instead, **bpf_get_stackid**\ () can collect up to | |
1043 | * **PERF_MAX_STACK_DEPTH** both kernel and user frames. Note that | |
1044 | * this limit can be controlled with the **sysctl** program, and | |
1045 | * that it should be manually increased in order to profile long | |
1046 | * user stacks (such as stacks for Java programs). To do so, use: | |
1047 | * | |
1048 | * :: | |
1049 | * | |
1050 | * # sysctl kernel.perf_event_max_stack=<new value> | |
c456dec4 QM |
1051 | * Return |
1052 | * The positive or null stack id on success, or a negative error | |
1053 | * in case of failure. | |
1054 | * | |
1fdd08be QM |
1055 | * s64 bpf_csum_diff(__be32 *from, u32 from_size, __be32 *to, u32 to_size, __wsum seed) |
1056 | * Description | |
1057 | * Compute a checksum difference, from the raw buffer pointed by | |
1058 | * *from*, of length *from_size* (that must be a multiple of 4), | |
1059 | * towards the raw buffer pointed by *to*, of size *to_size* | |
1060 | * (same remark). An optional *seed* can be added to the value | |
1061 | * (this can be cascaded, the seed may come from a previous call | |
1062 | * to the helper). | |
1063 | * | |
1064 | * This is flexible enough to be used in several ways: | |
1065 | * | |
1066 | * * With *from_size* == 0, *to_size* > 0 and *seed* set to | |
1067 | * checksum, it can be used when pushing new data. | |
1068 | * * With *from_size* > 0, *to_size* == 0 and *seed* set to | |
1069 | * checksum, it can be used when removing data from a packet. | |
1070 | * * With *from_size* > 0, *to_size* > 0 and *seed* set to 0, it | |
1071 | * can be used to compute a diff. Note that *from_size* and | |
1072 | * *to_size* do not need to be equal. | |
1073 | * | |
1074 | * This helper can be used in combination with | |
1075 | * **bpf_l3_csum_replace**\ () and **bpf_l4_csum_replace**\ (), to | |
1076 | * which one can feed in the difference computed with | |
1077 | * **bpf_csum_diff**\ (). | |
1078 | * Return | |
1079 | * The checksum result, or a negative error code in case of | |
1080 | * failure. | |
1081 | * | |
1082 | * int bpf_skb_get_tunnel_opt(struct sk_buff *skb, u8 *opt, u32 size) | |
1083 | * Description | |
1084 | * Retrieve tunnel options metadata for the packet associated to | |
1085 | * *skb*, and store the raw tunnel option data to the buffer *opt* | |
1086 | * of *size*. | |
1087 | * | |
1088 | * This helper can be used with encapsulation devices that can | |
1089 | * operate in "collect metadata" mode (please refer to the related | |
1090 | * note in the description of **bpf_skb_get_tunnel_key**\ () for | |
1091 | * more details). A particular example where this can be used is | |
1092 | * in combination with the Geneve encapsulation protocol, where it | |
1093 | * allows for pushing (with **bpf_skb_get_tunnel_opt**\ () helper) | |
1094 | * and retrieving arbitrary TLVs (Type-Length-Value headers) from | |
1095 | * the eBPF program. This allows for full customization of these | |
1096 | * headers. | |
1097 | * Return | |
1098 | * The size of the option data retrieved. | |
1099 | * | |
1100 | * int bpf_skb_set_tunnel_opt(struct sk_buff *skb, u8 *opt, u32 size) | |
1101 | * Description | |
1102 | * Set tunnel options metadata for the packet associated to *skb* | |
1103 | * to the option data contained in the raw buffer *opt* of *size*. | |
1104 | * | |
1105 | * See also the description of the **bpf_skb_get_tunnel_opt**\ () | |
1106 | * helper for additional information. | |
1107 | * Return | |
1108 | * 0 on success, or a negative error in case of failure. | |
1109 | * | |
1110 | * int bpf_skb_change_proto(struct sk_buff *skb, __be16 proto, u64 flags) | |
1111 | * Description | |
1112 | * Change the protocol of the *skb* to *proto*. Currently | |
1113 | * supported are transition from IPv4 to IPv6, and from IPv6 to | |
1114 | * IPv4. The helper takes care of the groundwork for the | |
1115 | * transition, including resizing the socket buffer. The eBPF | |
1116 | * program is expected to fill the new headers, if any, via | |
1117 | * **skb_store_bytes**\ () and to recompute the checksums with | |
1118 | * **bpf_l3_csum_replace**\ () and **bpf_l4_csum_replace**\ | |
1119 | * (). The main case for this helper is to perform NAT64 | |
1120 | * operations out of an eBPF program. | |
1121 | * | |
1122 | * Internally, the GSO type is marked as dodgy so that headers are | |
1123 | * checked and segments are recalculated by the GSO/GRO engine. | |
1124 | * The size for GSO target is adapted as well. | |
1125 | * | |
1126 | * All values for *flags* are reserved for future usage, and must | |
1127 | * be left at zero. | |
1128 | * | |
1129 | * A call to this helper is susceptible to change the underlaying | |
1130 | * packet buffer. Therefore, at load time, all checks on pointers | |
1131 | * previously done by the verifier are invalidated and must be | |
1132 | * performed again, if the helper is used in combination with | |
1133 | * direct packet access. | |
1134 | * Return | |
1135 | * 0 on success, or a negative error in case of failure. | |
1136 | * | |
1137 | * int bpf_skb_change_type(struct sk_buff *skb, u32 type) | |
1138 | * Description | |
1139 | * Change the packet type for the packet associated to *skb*. This | |
1140 | * comes down to setting *skb*\ **->pkt_type** to *type*, except | |
1141 | * the eBPF program does not have a write access to *skb*\ | |
1142 | * **->pkt_type** beside this helper. Using a helper here allows | |
1143 | * for graceful handling of errors. | |
1144 | * | |
1145 | * The major use case is to change incoming *skb*s to | |
1146 | * **PACKET_HOST** in a programmatic way instead of having to | |
1147 | * recirculate via **redirect**\ (..., **BPF_F_INGRESS**), for | |
1148 | * example. | |
1149 | * | |
1150 | * Note that *type* only allows certain values. At this time, they | |
1151 | * are: | |
1152 | * | |
1153 | * **PACKET_HOST** | |
1154 | * Packet is for us. | |
1155 | * **PACKET_BROADCAST** | |
1156 | * Send packet to all. | |
1157 | * **PACKET_MULTICAST** | |
1158 | * Send packet to group. | |
1159 | * **PACKET_OTHERHOST** | |
1160 | * Send packet to someone else. | |
1161 | * Return | |
1162 | * 0 on success, or a negative error in case of failure. | |
1163 | * | |
c6b5fb86 QM |
1164 | * int bpf_skb_under_cgroup(struct sk_buff *skb, struct bpf_map *map, u32 index) |
1165 | * Description | |
1166 | * Check whether *skb* is a descendant of the cgroup2 held by | |
1167 | * *map* of type **BPF_MAP_TYPE_CGROUP_ARRAY**, at *index*. | |
1168 | * Return | |
1169 | * The return value depends on the result of the test, and can be: | |
1170 | * | |
1171 | * * 0, if the *skb* failed the cgroup2 descendant test. | |
1172 | * * 1, if the *skb* succeeded the cgroup2 descendant test. | |
1173 | * * A negative error code, if an error occurred. | |
1174 | * | |
fa15601a QM |
1175 | * u32 bpf_get_hash_recalc(struct sk_buff *skb) |
1176 | * Description | |
1177 | * Retrieve the hash of the packet, *skb*\ **->hash**. If it is | |
1178 | * not set, in particular if the hash was cleared due to mangling, | |
1179 | * recompute this hash. Later accesses to the hash can be done | |
1180 | * directly with *skb*\ **->hash**. | |
1181 | * | |
1182 | * Calling **bpf_set_hash_invalid**\ (), changing a packet | |
1183 | * prototype with **bpf_skb_change_proto**\ (), or calling | |
1184 | * **bpf_skb_store_bytes**\ () with the | |
1185 | * **BPF_F_INVALIDATE_HASH** are actions susceptible to clear | |
1186 | * the hash and to trigger a new computation for the next call to | |
1187 | * **bpf_get_hash_recalc**\ (). | |
1188 | * Return | |
1189 | * The 32-bit hash. | |
1190 | * | |
c456dec4 QM |
1191 | * u64 bpf_get_current_task(void) |
1192 | * Return | |
1193 | * A pointer to the current task struct. | |
fa15601a | 1194 | * |
c6b5fb86 QM |
1195 | * int bpf_probe_write_user(void *dst, const void *src, u32 len) |
1196 | * Description | |
1197 | * Attempt in a safe way to write *len* bytes from the buffer | |
1198 | * *src* to *dst* in memory. It only works for threads that are in | |
1199 | * user context, and *dst* must be a valid user space address. | |
1200 | * | |
1201 | * This helper should not be used to implement any kind of | |
1202 | * security mechanism because of TOC-TOU attacks, but rather to | |
1203 | * debug, divert, and manipulate execution of semi-cooperative | |
1204 | * processes. | |
1205 | * | |
1206 | * Keep in mind that this feature is meant for experiments, and it | |
1207 | * has a risk of crashing the system and running programs. | |
1208 | * Therefore, when an eBPF program using this helper is attached, | |
1209 | * a warning including PID and process name is printed to kernel | |
1210 | * logs. | |
1211 | * Return | |
1212 | * 0 on success, or a negative error in case of failure. | |
1213 | * | |
1214 | * int bpf_current_task_under_cgroup(struct bpf_map *map, u32 index) | |
1215 | * Description | |
1216 | * Check whether the probe is being run is the context of a given | |
1217 | * subset of the cgroup2 hierarchy. The cgroup2 to test is held by | |
1218 | * *map* of type **BPF_MAP_TYPE_CGROUP_ARRAY**, at *index*. | |
1219 | * Return | |
1220 | * The return value depends on the result of the test, and can be: | |
1221 | * | |
1222 | * * 0, if the *skb* task belongs to the cgroup2. | |
1223 | * * 1, if the *skb* task does not belong to the cgroup2. | |
1224 | * * A negative error code, if an error occurred. | |
1225 | * | |
fa15601a QM |
1226 | * int bpf_skb_change_tail(struct sk_buff *skb, u32 len, u64 flags) |
1227 | * Description | |
1228 | * Resize (trim or grow) the packet associated to *skb* to the | |
1229 | * new *len*. The *flags* are reserved for future usage, and must | |
1230 | * be left at zero. | |
1231 | * | |
1232 | * The basic idea is that the helper performs the needed work to | |
1233 | * change the size of the packet, then the eBPF program rewrites | |
1234 | * the rest via helpers like **bpf_skb_store_bytes**\ (), | |
1235 | * **bpf_l3_csum_replace**\ (), **bpf_l3_csum_replace**\ () | |
1236 | * and others. This helper is a slow path utility intended for | |
1237 | * replies with control messages. And because it is targeted for | |
1238 | * slow path, the helper itself can afford to be slow: it | |
1239 | * implicitly linearizes, unclones and drops offloads from the | |
1240 | * *skb*. | |
1241 | * | |
1242 | * A call to this helper is susceptible to change the underlaying | |
1243 | * packet buffer. Therefore, at load time, all checks on pointers | |
1244 | * previously done by the verifier are invalidated and must be | |
1245 | * performed again, if the helper is used in combination with | |
1246 | * direct packet access. | |
1247 | * Return | |
1248 | * 0 on success, or a negative error in case of failure. | |
1249 | * | |
1250 | * int bpf_skb_pull_data(struct sk_buff *skb, u32 len) | |
1251 | * Description | |
1252 | * Pull in non-linear data in case the *skb* is non-linear and not | |
1253 | * all of *len* are part of the linear section. Make *len* bytes | |
1254 | * from *skb* readable and writable. If a zero value is passed for | |
1255 | * *len*, then the whole length of the *skb* is pulled. | |
1256 | * | |
1257 | * This helper is only needed for reading and writing with direct | |
1258 | * packet access. | |
1259 | * | |
1260 | * For direct packet access, testing that offsets to access | |
1261 | * are within packet boundaries (test on *skb*\ **->data_end**) is | |
1262 | * susceptible to fail if offsets are invalid, or if the requested | |
1263 | * data is in non-linear parts of the *skb*. On failure the | |
1264 | * program can just bail out, or in the case of a non-linear | |
1265 | * buffer, use a helper to make the data available. The | |
1266 | * **bpf_skb_load_bytes**\ () helper is a first solution to access | |
1267 | * the data. Another one consists in using **bpf_skb_pull_data** | |
1268 | * to pull in once the non-linear parts, then retesting and | |
1269 | * eventually access the data. | |
1270 | * | |
1271 | * At the same time, this also makes sure the *skb* is uncloned, | |
1272 | * which is a necessary condition for direct write. As this needs | |
1273 | * to be an invariant for the write part only, the verifier | |
1274 | * detects writes and adds a prologue that is calling | |
1275 | * **bpf_skb_pull_data()** to effectively unclone the *skb* from | |
1276 | * the very beginning in case it is indeed cloned. | |
1277 | * | |
1278 | * A call to this helper is susceptible to change the underlaying | |
1279 | * packet buffer. Therefore, at load time, all checks on pointers | |
1280 | * previously done by the verifier are invalidated and must be | |
1281 | * performed again, if the helper is used in combination with | |
1282 | * direct packet access. | |
1283 | * Return | |
1284 | * 0 on success, or a negative error in case of failure. | |
1285 | * | |
1286 | * s64 bpf_csum_update(struct sk_buff *skb, __wsum csum) | |
1287 | * Description | |
1288 | * Add the checksum *csum* into *skb*\ **->csum** in case the | |
1289 | * driver has supplied a checksum for the entire packet into that | |
1290 | * field. Return an error otherwise. This helper is intended to be | |
1291 | * used in combination with **bpf_csum_diff**\ (), in particular | |
1292 | * when the checksum needs to be updated after data has been | |
1293 | * written into the packet through direct packet access. | |
1294 | * Return | |
1295 | * The checksum on success, or a negative error code in case of | |
1296 | * failure. | |
1297 | * | |
1298 | * void bpf_set_hash_invalid(struct sk_buff *skb) | |
1299 | * Description | |
1300 | * Invalidate the current *skb*\ **->hash**. It can be used after | |
1301 | * mangling on headers through direct packet access, in order to | |
1302 | * indicate that the hash is outdated and to trigger a | |
1303 | * recalculation the next time the kernel tries to access this | |
1304 | * hash or when the **bpf_get_hash_recalc**\ () helper is called. | |
1305 | * | |
1306 | * int bpf_get_numa_node_id(void) | |
1307 | * Description | |
1308 | * Return the id of the current NUMA node. The primary use case | |
1309 | * for this helper is the selection of sockets for the local NUMA | |
1310 | * node, when the program is attached to sockets using the | |
1311 | * **SO_ATTACH_REUSEPORT_EBPF** option (see also **socket(7)**), | |
1312 | * but the helper is also available to other eBPF program types, | |
1313 | * similarly to **bpf_get_smp_processor_id**\ (). | |
1314 | * Return | |
1315 | * The id of current NUMA node. | |
1316 | * | |
c6b5fb86 QM |
1317 | * int bpf_skb_change_head(struct sk_buff *skb, u32 len, u64 flags) |
1318 | * Description | |
1319 | * Grows headroom of packet associated to *skb* and adjusts the | |
1320 | * offset of the MAC header accordingly, adding *len* bytes of | |
1321 | * space. It automatically extends and reallocates memory as | |
1322 | * required. | |
1323 | * | |
1324 | * This helper can be used on a layer 3 *skb* to push a MAC header | |
1325 | * for redirection into a layer 2 device. | |
1326 | * | |
1327 | * All values for *flags* are reserved for future usage, and must | |
1328 | * be left at zero. | |
1329 | * | |
1330 | * A call to this helper is susceptible to change the underlaying | |
1331 | * packet buffer. Therefore, at load time, all checks on pointers | |
1332 | * previously done by the verifier are invalidated and must be | |
1333 | * performed again, if the helper is used in combination with | |
1334 | * direct packet access. | |
1335 | * Return | |
1336 | * 0 on success, or a negative error in case of failure. | |
1337 | * | |
1338 | * int bpf_xdp_adjust_head(struct xdp_buff *xdp_md, int delta) | |
1339 | * Description | |
1340 | * Adjust (move) *xdp_md*\ **->data** by *delta* bytes. Note that | |
1341 | * it is possible to use a negative value for *delta*. This helper | |
1342 | * can be used to prepare the packet for pushing or popping | |
1343 | * headers. | |
1344 | * | |
1345 | * A call to this helper is susceptible to change the underlaying | |
1346 | * packet buffer. Therefore, at load time, all checks on pointers | |
1347 | * previously done by the verifier are invalidated and must be | |
1348 | * performed again, if the helper is used in combination with | |
1349 | * direct packet access. | |
1350 | * Return | |
1351 | * 0 on success, or a negative error in case of failure. | |
1352 | * | |
1353 | * int bpf_probe_read_str(void *dst, int size, const void *unsafe_ptr) | |
1354 | * Description | |
1355 | * Copy a NUL terminated string from an unsafe address | |
1356 | * *unsafe_ptr* to *dst*. The *size* should include the | |
1357 | * terminating NUL byte. In case the string length is smaller than | |
1358 | * *size*, the target is not padded with further NUL bytes. If the | |
1359 | * string length is larger than *size*, just *size*-1 bytes are | |
1360 | * copied and the last byte is set to NUL. | |
1361 | * | |
1362 | * On success, the length of the copied string is returned. This | |
1363 | * makes this helper useful in tracing programs for reading | |
1364 | * strings, and more importantly to get its length at runtime. See | |
1365 | * the following snippet: | |
1366 | * | |
1367 | * :: | |
1368 | * | |
1369 | * SEC("kprobe/sys_open") | |
1370 | * void bpf_sys_open(struct pt_regs *ctx) | |
1371 | * { | |
1372 | * char buf[PATHLEN]; // PATHLEN is defined to 256 | |
1373 | * int res = bpf_probe_read_str(buf, sizeof(buf), | |
1374 | * ctx->di); | |
1375 | * | |
1376 | * // Consume buf, for example push it to | |
1377 | * // userspace via bpf_perf_event_output(); we | |
1378 | * // can use res (the string length) as event | |
1379 | * // size, after checking its boundaries. | |
1380 | * } | |
1381 | * | |
1382 | * In comparison, using **bpf_probe_read()** helper here instead | |
1383 | * to read the string would require to estimate the length at | |
1384 | * compile time, and would often result in copying more memory | |
1385 | * than necessary. | |
1386 | * | |
1387 | * Another useful use case is when parsing individual process | |
1388 | * arguments or individual environment variables navigating | |
1389 | * *current*\ **->mm->arg_start** and *current*\ | |
1390 | * **->mm->env_start**: using this helper and the return value, | |
1391 | * one can quickly iterate at the right offset of the memory area. | |
1392 | * Return | |
1393 | * On success, the strictly positive length of the string, | |
1394 | * including the trailing NUL character. On error, a negative | |
1395 | * value. | |
1396 | * | |
1397 | * u64 bpf_get_socket_cookie(struct sk_buff *skb) | |
1398 | * Description | |
1399 | * If the **struct sk_buff** pointed by *skb* has a known socket, | |
1400 | * retrieve the cookie (generated by the kernel) of this socket. | |
1401 | * If no cookie has been set yet, generate a new cookie. Once | |
1402 | * generated, the socket cookie remains stable for the life of the | |
1403 | * socket. This helper can be useful for monitoring per socket | |
1404 | * networking traffic statistics as it provides a unique socket | |
1405 | * identifier per namespace. | |
1406 | * Return | |
1407 | * A 8-byte long non-decreasing number on success, or 0 if the | |
1408 | * socket field is missing inside *skb*. | |
1409 | * | |
d692f113 AI |
1410 | * u64 bpf_get_socket_cookie(struct bpf_sock_addr *ctx) |
1411 | * Description | |
1412 | * Equivalent to bpf_get_socket_cookie() helper that accepts | |
1413 | * *skb*, but gets socket from **struct bpf_sock_addr** contex. | |
1414 | * Return | |
1415 | * A 8-byte long non-decreasing number. | |
1416 | * | |
1417 | * u64 bpf_get_socket_cookie(struct bpf_sock_ops *ctx) | |
1418 | * Description | |
1419 | * Equivalent to bpf_get_socket_cookie() helper that accepts | |
1420 | * *skb*, but gets socket from **struct bpf_sock_ops** contex. | |
1421 | * Return | |
1422 | * A 8-byte long non-decreasing number. | |
1423 | * | |
c6b5fb86 QM |
1424 | * u32 bpf_get_socket_uid(struct sk_buff *skb) |
1425 | * Return | |
1426 | * The owner UID of the socket associated to *skb*. If the socket | |
1427 | * is **NULL**, or if it is not a full socket (i.e. if it is a | |
1428 | * time-wait or a request socket instead), **overflowuid** value | |
1429 | * is returned (note that **overflowuid** might also be the actual | |
1430 | * UID value for the socket). | |
1431 | * | |
fa15601a QM |
1432 | * u32 bpf_set_hash(struct sk_buff *skb, u32 hash) |
1433 | * Description | |
1434 | * Set the full hash for *skb* (set the field *skb*\ **->hash**) | |
1435 | * to value *hash*. | |
1436 | * Return | |
1437 | * 0 | |
1438 | * | |
a3ef8e9a | 1439 | * int bpf_setsockopt(struct bpf_sock_ops *bpf_socket, int level, int optname, char *optval, int optlen) |
7aa79a86 QM |
1440 | * Description |
1441 | * Emulate a call to **setsockopt()** on the socket associated to | |
1442 | * *bpf_socket*, which must be a full socket. The *level* at | |
1443 | * which the option resides and the name *optname* of the option | |
1444 | * must be specified, see **setsockopt(2)** for more information. | |
1445 | * The option value of length *optlen* is pointed by *optval*. | |
1446 | * | |
1447 | * This helper actually implements a subset of **setsockopt()**. | |
1448 | * It supports the following *level*\ s: | |
1449 | * | |
1450 | * * **SOL_SOCKET**, which supports the following *optname*\ s: | |
1451 | * **SO_RCVBUF**, **SO_SNDBUF**, **SO_MAX_PACING_RATE**, | |
1452 | * **SO_PRIORITY**, **SO_RCVLOWAT**, **SO_MARK**. | |
1453 | * * **IPPROTO_TCP**, which supports the following *optname*\ s: | |
1454 | * **TCP_CONGESTION**, **TCP_BPF_IW**, | |
1455 | * **TCP_BPF_SNDCWND_CLAMP**. | |
1456 | * * **IPPROTO_IP**, which supports *optname* **IP_TOS**. | |
1457 | * * **IPPROTO_IPV6**, which supports *optname* **IPV6_TCLASS**. | |
1458 | * Return | |
1459 | * 0 on success, or a negative error in case of failure. | |
1460 | * | |
b55cbc8d | 1461 | * int bpf_skb_adjust_room(struct sk_buff *skb, s32 len_diff, u32 mode, u64 flags) |
fa15601a QM |
1462 | * Description |
1463 | * Grow or shrink the room for data in the packet associated to | |
1464 | * *skb* by *len_diff*, and according to the selected *mode*. | |
1465 | * | |
1466 | * There is a single supported mode at this time: | |
1467 | * | |
1468 | * * **BPF_ADJ_ROOM_NET**: Adjust room at the network layer | |
1469 | * (room space is added or removed below the layer 3 header). | |
1470 | * | |
1471 | * All values for *flags* are reserved for future usage, and must | |
1472 | * be left at zero. | |
1473 | * | |
1474 | * A call to this helper is susceptible to change the underlaying | |
1475 | * packet buffer. Therefore, at load time, all checks on pointers | |
1476 | * previously done by the verifier are invalidated and must be | |
1477 | * performed again, if the helper is used in combination with | |
1478 | * direct packet access. | |
1479 | * Return | |
1480 | * 0 on success, or a negative error in case of failure. | |
1481 | * | |
ab127040 QM |
1482 | * int bpf_redirect_map(struct bpf_map *map, u32 key, u64 flags) |
1483 | * Description | |
1484 | * Redirect the packet to the endpoint referenced by *map* at | |
1485 | * index *key*. Depending on its type, this *map* can contain | |
1486 | * references to net devices (for forwarding packets through other | |
1487 | * ports), or to CPUs (for redirecting XDP frames to another CPU; | |
1488 | * but this is only implemented for native XDP (with driver | |
1489 | * support) as of this writing). | |
1490 | * | |
1491 | * All values for *flags* are reserved for future usage, and must | |
1492 | * be left at zero. | |
1493 | * | |
1494 | * When used to redirect packets to net devices, this helper | |
1495 | * provides a high performance increase over **bpf_redirect**\ (). | |
1496 | * This is due to various implementation details of the underlying | |
1497 | * mechanisms, one of which is the fact that **bpf_redirect_map**\ | |
1498 | * () tries to send packet as a "bulk" to the device. | |
1499 | * Return | |
1500 | * **XDP_REDIRECT** on success, or **XDP_ABORTED** on error. | |
1501 | * | |
1502 | * int bpf_sk_redirect_map(struct bpf_map *map, u32 key, u64 flags) | |
1503 | * Description | |
1504 | * Redirect the packet to the socket referenced by *map* (of type | |
1505 | * **BPF_MAP_TYPE_SOCKMAP**) at index *key*. Both ingress and | |
1506 | * egress interfaces can be used for redirection. The | |
1507 | * **BPF_F_INGRESS** value in *flags* is used to make the | |
1508 | * distinction (ingress path is selected if the flag is present, | |
1509 | * egress path otherwise). This is the only flag supported for now. | |
1510 | * Return | |
1511 | * **SK_PASS** on success, or **SK_DROP** on error. | |
1512 | * | |
a3ef8e9a | 1513 | * int bpf_sock_map_update(struct bpf_sock_ops *skops, struct bpf_map *map, void *key, u64 flags) |
ab127040 QM |
1514 | * Description |
1515 | * Add an entry to, or update a *map* referencing sockets. The | |
1516 | * *skops* is used as a new value for the entry associated to | |
1517 | * *key*. *flags* is one of: | |
1518 | * | |
1519 | * **BPF_NOEXIST** | |
1520 | * The entry for *key* must not exist in the map. | |
1521 | * **BPF_EXIST** | |
1522 | * The entry for *key* must already exist in the map. | |
1523 | * **BPF_ANY** | |
1524 | * No condition on the existence of the entry for *key*. | |
1525 | * | |
1526 | * If the *map* has eBPF programs (parser and verdict), those will | |
1527 | * be inherited by the socket being added. If the socket is | |
1528 | * already attached to eBPF programs, this results in an error. | |
1529 | * Return | |
1530 | * 0 on success, or a negative error in case of failure. | |
1531 | * | |
fa15601a QM |
1532 | * int bpf_xdp_adjust_meta(struct xdp_buff *xdp_md, int delta) |
1533 | * Description | |
1534 | * Adjust the address pointed by *xdp_md*\ **->data_meta** by | |
1535 | * *delta* (which can be positive or negative). Note that this | |
1536 | * operation modifies the address stored in *xdp_md*\ **->data**, | |
1537 | * so the latter must be loaded only after the helper has been | |
1538 | * called. | |
1539 | * | |
1540 | * The use of *xdp_md*\ **->data_meta** is optional and programs | |
1541 | * are not required to use it. The rationale is that when the | |
1542 | * packet is processed with XDP (e.g. as DoS filter), it is | |
1543 | * possible to push further meta data along with it before passing | |
1544 | * to the stack, and to give the guarantee that an ingress eBPF | |
1545 | * program attached as a TC classifier on the same device can pick | |
1546 | * this up for further post-processing. Since TC works with socket | |
1547 | * buffers, it remains possible to set from XDP the **mark** or | |
1548 | * **priority** pointers, or other pointers for the socket buffer. | |
1549 | * Having this scratch space generic and programmable allows for | |
1550 | * more flexibility as the user is free to store whatever meta | |
1551 | * data they need. | |
1552 | * | |
1553 | * A call to this helper is susceptible to change the underlaying | |
1554 | * packet buffer. Therefore, at load time, all checks on pointers | |
1555 | * previously done by the verifier are invalidated and must be | |
1556 | * performed again, if the helper is used in combination with | |
1557 | * direct packet access. | |
1558 | * Return | |
1559 | * 0 on success, or a negative error in case of failure. | |
7aa79a86 QM |
1560 | * |
1561 | * int bpf_perf_event_read_value(struct bpf_map *map, u64 flags, struct bpf_perf_event_value *buf, u32 buf_size) | |
1562 | * Description | |
1563 | * Read the value of a perf event counter, and store it into *buf* | |
1564 | * of size *buf_size*. This helper relies on a *map* of type | |
1565 | * **BPF_MAP_TYPE_PERF_EVENT_ARRAY**. The nature of the perf event | |
1566 | * counter is selected when *map* is updated with perf event file | |
1567 | * descriptors. The *map* is an array whose size is the number of | |
1568 | * available CPUs, and each cell contains a value relative to one | |
1569 | * CPU. The value to retrieve is indicated by *flags*, that | |
1570 | * contains the index of the CPU to look up, masked with | |
1571 | * **BPF_F_INDEX_MASK**. Alternatively, *flags* can be set to | |
1572 | * **BPF_F_CURRENT_CPU** to indicate that the value for the | |
1573 | * current CPU should be retrieved. | |
1574 | * | |
1575 | * This helper behaves in a way close to | |
1576 | * **bpf_perf_event_read**\ () helper, save that instead of | |
1577 | * just returning the value observed, it fills the *buf* | |
1578 | * structure. This allows for additional data to be retrieved: in | |
1579 | * particular, the enabled and running times (in *buf*\ | |
1580 | * **->enabled** and *buf*\ **->running**, respectively) are | |
1581 | * copied. In general, **bpf_perf_event_read_value**\ () is | |
1582 | * recommended over **bpf_perf_event_read**\ (), which has some | |
1583 | * ABI issues and provides fewer functionalities. | |
1584 | * | |
1585 | * These values are interesting, because hardware PMU (Performance | |
1586 | * Monitoring Unit) counters are limited resources. When there are | |
1587 | * more PMU based perf events opened than available counters, | |
1588 | * kernel will multiplex these events so each event gets certain | |
1589 | * percentage (but not all) of the PMU time. In case that | |
1590 | * multiplexing happens, the number of samples or counter value | |
1591 | * will not reflect the case compared to when no multiplexing | |
1592 | * occurs. This makes comparison between different runs difficult. | |
1593 | * Typically, the counter value should be normalized before | |
1594 | * comparing to other experiments. The usual normalization is done | |
1595 | * as follows. | |
1596 | * | |
1597 | * :: | |
1598 | * | |
1599 | * normalized_counter = counter * t_enabled / t_running | |
1600 | * | |
1601 | * Where t_enabled is the time enabled for event and t_running is | |
1602 | * the time running for event since last normalization. The | |
1603 | * enabled and running times are accumulated since the perf event | |
1604 | * open. To achieve scaling factor between two invocations of an | |
1605 | * eBPF program, users can can use CPU id as the key (which is | |
1606 | * typical for perf array usage model) to remember the previous | |
1607 | * value and do the calculation inside the eBPF program. | |
1608 | * Return | |
1609 | * 0 on success, or a negative error in case of failure. | |
1610 | * | |
a3ef8e9a | 1611 | * int bpf_perf_prog_read_value(struct bpf_perf_event_data *ctx, struct bpf_perf_event_value *buf, u32 buf_size) |
7aa79a86 QM |
1612 | * Description |
1613 | * For en eBPF program attached to a perf event, retrieve the | |
1614 | * value of the event counter associated to *ctx* and store it in | |
1615 | * the structure pointed by *buf* and of size *buf_size*. Enabled | |
1616 | * and running times are also stored in the structure (see | |
1617 | * description of helper **bpf_perf_event_read_value**\ () for | |
1618 | * more details). | |
1619 | * Return | |
1620 | * 0 on success, or a negative error in case of failure. | |
1621 | * | |
a3ef8e9a | 1622 | * int bpf_getsockopt(struct bpf_sock_ops *bpf_socket, int level, int optname, char *optval, int optlen) |
7aa79a86 QM |
1623 | * Description |
1624 | * Emulate a call to **getsockopt()** on the socket associated to | |
1625 | * *bpf_socket*, which must be a full socket. The *level* at | |
1626 | * which the option resides and the name *optname* of the option | |
1627 | * must be specified, see **getsockopt(2)** for more information. | |
1628 | * The retrieved value is stored in the structure pointed by | |
1629 | * *opval* and of length *optlen*. | |
1630 | * | |
1631 | * This helper actually implements a subset of **getsockopt()**. | |
1632 | * It supports the following *level*\ s: | |
1633 | * | |
1634 | * * **IPPROTO_TCP**, which supports *optname* | |
1635 | * **TCP_CONGESTION**. | |
1636 | * * **IPPROTO_IP**, which supports *optname* **IP_TOS**. | |
1637 | * * **IPPROTO_IPV6**, which supports *optname* **IPV6_TCLASS**. | |
1638 | * Return | |
1639 | * 0 on success, or a negative error in case of failure. | |
1640 | * | |
1641 | * int bpf_override_return(struct pt_reg *regs, u64 rc) | |
1642 | * Description | |
1643 | * Used for error injection, this helper uses kprobes to override | |
1644 | * the return value of the probed function, and to set it to *rc*. | |
1645 | * The first argument is the context *regs* on which the kprobe | |
1646 | * works. | |
1647 | * | |
1648 | * This helper works by setting setting the PC (program counter) | |
1649 | * to an override function which is run in place of the original | |
1650 | * probed function. This means the probed function is not run at | |
1651 | * all. The replacement function just returns with the required | |
1652 | * value. | |
1653 | * | |
1654 | * This helper has security implications, and thus is subject to | |
1655 | * restrictions. It is only available if the kernel was compiled | |
1656 | * with the **CONFIG_BPF_KPROBE_OVERRIDE** configuration | |
1657 | * option, and in this case it only works on functions tagged with | |
1658 | * **ALLOW_ERROR_INJECTION** in the kernel code. | |
1659 | * | |
1660 | * Also, the helper is only available for the architectures having | |
1661 | * the CONFIG_FUNCTION_ERROR_INJECTION option. As of this writing, | |
1662 | * x86 architecture is the only one to support this feature. | |
1663 | * Return | |
1664 | * 0 | |
1665 | * | |
a3ef8e9a | 1666 | * int bpf_sock_ops_cb_flags_set(struct bpf_sock_ops *bpf_sock, int argval) |
7aa79a86 QM |
1667 | * Description |
1668 | * Attempt to set the value of the **bpf_sock_ops_cb_flags** field | |
1669 | * for the full TCP socket associated to *bpf_sock_ops* to | |
1670 | * *argval*. | |
1671 | * | |
1672 | * The primary use of this field is to determine if there should | |
1673 | * be calls to eBPF programs of type | |
1674 | * **BPF_PROG_TYPE_SOCK_OPS** at various points in the TCP | |
1675 | * code. A program of the same type can change its value, per | |
1676 | * connection and as necessary, when the connection is | |
1677 | * established. This field is directly accessible for reading, but | |
1678 | * this helper must be used for updates in order to return an | |
1679 | * error if an eBPF program tries to set a callback that is not | |
1680 | * supported in the current kernel. | |
1681 | * | |
1682 | * The supported callback values that *argval* can combine are: | |
1683 | * | |
1684 | * * **BPF_SOCK_OPS_RTO_CB_FLAG** (retransmission time out) | |
1685 | * * **BPF_SOCK_OPS_RETRANS_CB_FLAG** (retransmission) | |
1686 | * * **BPF_SOCK_OPS_STATE_CB_FLAG** (TCP state change) | |
1687 | * | |
1688 | * Here are some examples of where one could call such eBPF | |
1689 | * program: | |
1690 | * | |
1691 | * * When RTO fires. | |
1692 | * * When a packet is retransmitted. | |
1693 | * * When the connection terminates. | |
1694 | * * When a packet is sent. | |
1695 | * * When a packet is received. | |
1696 | * Return | |
1697 | * Code **-EINVAL** if the socket is not a full TCP socket; | |
1698 | * otherwise, a positive number containing the bits that could not | |
1699 | * be set is returned (which comes down to 0 if all bits were set | |
1700 | * as required). | |
1701 | * | |
ab127040 QM |
1702 | * int bpf_msg_redirect_map(struct sk_msg_buff *msg, struct bpf_map *map, u32 key, u64 flags) |
1703 | * Description | |
1704 | * This helper is used in programs implementing policies at the | |
1705 | * socket level. If the message *msg* is allowed to pass (i.e. if | |
1706 | * the verdict eBPF program returns **SK_PASS**), redirect it to | |
1707 | * the socket referenced by *map* (of type | |
1708 | * **BPF_MAP_TYPE_SOCKMAP**) at index *key*. Both ingress and | |
1709 | * egress interfaces can be used for redirection. The | |
1710 | * **BPF_F_INGRESS** value in *flags* is used to make the | |
1711 | * distinction (ingress path is selected if the flag is present, | |
1712 | * egress path otherwise). This is the only flag supported for now. | |
1713 | * Return | |
1714 | * **SK_PASS** on success, or **SK_DROP** on error. | |
1715 | * | |
1716 | * int bpf_msg_apply_bytes(struct sk_msg_buff *msg, u32 bytes) | |
1717 | * Description | |
1718 | * For socket policies, apply the verdict of the eBPF program to | |
1719 | * the next *bytes* (number of bytes) of message *msg*. | |
1720 | * | |
1721 | * For example, this helper can be used in the following cases: | |
1722 | * | |
1723 | * * A single **sendmsg**\ () or **sendfile**\ () system call | |
1724 | * contains multiple logical messages that the eBPF program is | |
1725 | * supposed to read and for which it should apply a verdict. | |
1726 | * * An eBPF program only cares to read the first *bytes* of a | |
1727 | * *msg*. If the message has a large payload, then setting up | |
1728 | * and calling the eBPF program repeatedly for all bytes, even | |
1729 | * though the verdict is already known, would create unnecessary | |
1730 | * overhead. | |
1731 | * | |
1732 | * When called from within an eBPF program, the helper sets a | |
1733 | * counter internal to the BPF infrastructure, that is used to | |
1734 | * apply the last verdict to the next *bytes*. If *bytes* is | |
1735 | * smaller than the current data being processed from a | |
1736 | * **sendmsg**\ () or **sendfile**\ () system call, the first | |
1737 | * *bytes* will be sent and the eBPF program will be re-run with | |
1738 | * the pointer for start of data pointing to byte number *bytes* | |
1739 | * **+ 1**. If *bytes* is larger than the current data being | |
1740 | * processed, then the eBPF verdict will be applied to multiple | |
1741 | * **sendmsg**\ () or **sendfile**\ () calls until *bytes* are | |
1742 | * consumed. | |
1743 | * | |
1744 | * Note that if a socket closes with the internal counter holding | |
1745 | * a non-zero value, this is not a problem because data is not | |
1746 | * being buffered for *bytes* and is sent as it is received. | |
1747 | * Return | |
1748 | * 0 | |
1749 | * | |
1750 | * int bpf_msg_cork_bytes(struct sk_msg_buff *msg, u32 bytes) | |
1751 | * Description | |
1752 | * For socket policies, prevent the execution of the verdict eBPF | |
1753 | * program for message *msg* until *bytes* (byte number) have been | |
1754 | * accumulated. | |
1755 | * | |
1756 | * This can be used when one needs a specific number of bytes | |
1757 | * before a verdict can be assigned, even if the data spans | |
1758 | * multiple **sendmsg**\ () or **sendfile**\ () calls. The extreme | |
1759 | * case would be a user calling **sendmsg**\ () repeatedly with | |
1760 | * 1-byte long message segments. Obviously, this is bad for | |
1761 | * performance, but it is still valid. If the eBPF program needs | |
1762 | * *bytes* bytes to validate a header, this helper can be used to | |
1763 | * prevent the eBPF program to be called again until *bytes* have | |
1764 | * been accumulated. | |
1765 | * Return | |
1766 | * 0 | |
1767 | * | |
1768 | * int bpf_msg_pull_data(struct sk_msg_buff *msg, u32 start, u32 end, u64 flags) | |
1769 | * Description | |
1770 | * For socket policies, pull in non-linear data from user space | |
1771 | * for *msg* and set pointers *msg*\ **->data** and *msg*\ | |
1772 | * **->data_end** to *start* and *end* bytes offsets into *msg*, | |
1773 | * respectively. | |
1774 | * | |
1775 | * If a program of type **BPF_PROG_TYPE_SK_MSG** is run on a | |
1776 | * *msg* it can only parse data that the (**data**, **data_end**) | |
1777 | * pointers have already consumed. For **sendmsg**\ () hooks this | |
1778 | * is likely the first scatterlist element. But for calls relying | |
1779 | * on the **sendpage** handler (e.g. **sendfile**\ ()) this will | |
1780 | * be the range (**0**, **0**) because the data is shared with | |
1781 | * user space and by default the objective is to avoid allowing | |
1782 | * user space to modify data while (or after) eBPF verdict is | |
1783 | * being decided. This helper can be used to pull in data and to | |
1784 | * set the start and end pointer to given values. Data will be | |
1785 | * copied if necessary (i.e. if data was not linear and if start | |
1786 | * and end pointers do not point to the same chunk). | |
1787 | * | |
1788 | * A call to this helper is susceptible to change the underlaying | |
1789 | * packet buffer. Therefore, at load time, all checks on pointers | |
1790 | * previously done by the verifier are invalidated and must be | |
1791 | * performed again, if the helper is used in combination with | |
1792 | * direct packet access. | |
1793 | * | |
1794 | * All values for *flags* are reserved for future usage, and must | |
1795 | * be left at zero. | |
1796 | * Return | |
1797 | * 0 on success, or a negative error in case of failure. | |
1798 | * | |
a3ef8e9a | 1799 | * int bpf_bind(struct bpf_sock_addr *ctx, struct sockaddr *addr, int addr_len) |
7aa79a86 QM |
1800 | * Description |
1801 | * Bind the socket associated to *ctx* to the address pointed by | |
1802 | * *addr*, of length *addr_len*. This allows for making outgoing | |
1803 | * connection from the desired IP address, which can be useful for | |
1804 | * example when all processes inside a cgroup should use one | |
1805 | * single IP address on a host that has multiple IP configured. | |
1806 | * | |
1807 | * This helper works for IPv4 and IPv6, TCP and UDP sockets. The | |
1808 | * domain (*addr*\ **->sa_family**) must be **AF_INET** (or | |
1809 | * **AF_INET6**). Looking for a free port to bind to can be | |
1810 | * expensive, therefore binding to port is not permitted by the | |
1811 | * helper: *addr*\ **->sin_port** (or **sin6_port**, respectively) | |
1812 | * must be set to zero. | |
1813 | * Return | |
1814 | * 0 on success, or a negative error in case of failure. | |
2d020dd7 QM |
1815 | * |
1816 | * int bpf_xdp_adjust_tail(struct xdp_buff *xdp_md, int delta) | |
1817 | * Description | |
1818 | * Adjust (move) *xdp_md*\ **->data_end** by *delta* bytes. It is | |
1819 | * only possible to shrink the packet as of this writing, | |
1820 | * therefore *delta* must be a negative integer. | |
1821 | * | |
1822 | * A call to this helper is susceptible to change the underlaying | |
1823 | * packet buffer. Therefore, at load time, all checks on pointers | |
1824 | * previously done by the verifier are invalidated and must be | |
1825 | * performed again, if the helper is used in combination with | |
1826 | * direct packet access. | |
1827 | * Return | |
1828 | * 0 on success, or a negative error in case of failure. | |
1829 | * | |
1830 | * int bpf_skb_get_xfrm_state(struct sk_buff *skb, u32 index, struct bpf_xfrm_state *xfrm_state, u32 size, u64 flags) | |
1831 | * Description | |
1832 | * Retrieve the XFRM state (IP transform framework, see also | |
1833 | * **ip-xfrm(8)**) at *index* in XFRM "security path" for *skb*. | |
1834 | * | |
1835 | * The retrieved value is stored in the **struct bpf_xfrm_state** | |
1836 | * pointed by *xfrm_state* and of length *size*. | |
1837 | * | |
1838 | * All values for *flags* are reserved for future usage, and must | |
1839 | * be left at zero. | |
1840 | * | |
1841 | * This helper is available only if the kernel was compiled with | |
1842 | * **CONFIG_XFRM** configuration option. | |
1843 | * Return | |
1844 | * 0 on success, or a negative error in case of failure. | |
c195651e YS |
1845 | * |
1846 | * int bpf_get_stack(struct pt_regs *regs, void *buf, u32 size, u64 flags) | |
1847 | * Description | |
79552fbc QM |
1848 | * Return a user or a kernel stack in bpf program provided buffer. |
1849 | * To achieve this, the helper needs *ctx*, which is a pointer | |
1850 | * to the context on which the tracing program is executed. | |
1851 | * To store the stacktrace, the bpf program provides *buf* with | |
1852 | * a nonnegative *size*. | |
1853 | * | |
1854 | * The last argument, *flags*, holds the number of stack frames to | |
1855 | * skip (from 0 to 255), masked with | |
1856 | * **BPF_F_SKIP_FIELD_MASK**. The next bits can be used to set | |
1857 | * the following flags: | |
1858 | * | |
1859 | * **BPF_F_USER_STACK** | |
1860 | * Collect a user space stack instead of a kernel stack. | |
1861 | * **BPF_F_USER_BUILD_ID** | |
1862 | * Collect buildid+offset instead of ips for user stack, | |
1863 | * only valid if **BPF_F_USER_STACK** is also specified. | |
1864 | * | |
1865 | * **bpf_get_stack**\ () can collect up to | |
1866 | * **PERF_MAX_STACK_DEPTH** both kernel and user frames, subject | |
1867 | * to sufficient large buffer size. Note that | |
1868 | * this limit can be controlled with the **sysctl** program, and | |
1869 | * that it should be manually increased in order to profile long | |
1870 | * user stacks (such as stacks for Java programs). To do so, use: | |
1871 | * | |
1872 | * :: | |
1873 | * | |
1874 | * # sysctl kernel.perf_event_max_stack=<new value> | |
c195651e | 1875 | * Return |
7a279e93 QM |
1876 | * A non-negative value equal to or less than *size* on success, |
1877 | * or a negative error in case of failure. | |
4e1ec56c | 1878 | * |
2bae79d2 | 1879 | * int bpf_skb_load_bytes_relative(const struct sk_buff *skb, u32 offset, void *to, u32 len, u32 start_header) |
4e1ec56c DB |
1880 | * Description |
1881 | * This helper is similar to **bpf_skb_load_bytes**\ () in that | |
1882 | * it provides an easy way to load *len* bytes from *offset* | |
1883 | * from the packet associated to *skb*, into the buffer pointed | |
1884 | * by *to*. The difference to **bpf_skb_load_bytes**\ () is that | |
1885 | * a fifth argument *start_header* exists in order to select a | |
1886 | * base offset to start from. *start_header* can be one of: | |
1887 | * | |
1888 | * **BPF_HDR_START_MAC** | |
1889 | * Base offset to load data from is *skb*'s mac header. | |
1890 | * **BPF_HDR_START_NET** | |
1891 | * Base offset to load data from is *skb*'s network header. | |
1892 | * | |
1893 | * In general, "direct packet access" is the preferred method to | |
1894 | * access packet data, however, this helper is in particular useful | |
1895 | * in socket filters where *skb*\ **->data** does not always point | |
1896 | * to the start of the mac header and where "direct packet access" | |
1897 | * is not available. | |
4e1ec56c DB |
1898 | * Return |
1899 | * 0 on success, or a negative error in case of failure. | |
1900 | * | |
87f5fc7e DA |
1901 | * int bpf_fib_lookup(void *ctx, struct bpf_fib_lookup *params, int plen, u32 flags) |
1902 | * Description | |
1903 | * Do FIB lookup in kernel tables using parameters in *params*. | |
1904 | * If lookup is successful and result shows packet is to be | |
1905 | * forwarded, the neighbor tables are searched for the nexthop. | |
1906 | * If successful (ie., FIB lookup shows forwarding and nexthop | |
fa898d76 DA |
1907 | * is resolved), the nexthop address is returned in ipv4_dst |
1908 | * or ipv6_dst based on family, smac is set to mac address of | |
1909 | * egress device, dmac is set to nexthop mac address, rt_metric | |
4c79579b DA |
1910 | * is set to metric from route (IPv4/IPv6 only), and ifindex |
1911 | * is set to the device index of the nexthop from the FIB lookup. | |
87f5fc7e DA |
1912 | * |
1913 | * *plen* argument is the size of the passed in struct. | |
7a279e93 QM |
1914 | * *flags* argument can be a combination of one or more of the |
1915 | * following values: | |
87f5fc7e | 1916 | * |
7a279e93 QM |
1917 | * **BPF_FIB_LOOKUP_DIRECT** |
1918 | * Do a direct table lookup vs full lookup using FIB | |
1919 | * rules. | |
1920 | * **BPF_FIB_LOOKUP_OUTPUT** | |
1921 | * Perform lookup from an egress perspective (default is | |
1922 | * ingress). | |
87f5fc7e DA |
1923 | * |
1924 | * *ctx* is either **struct xdp_md** for XDP programs or | |
1925 | * **struct sk_buff** tc cls_act programs. | |
87f5fc7e | 1926 | * Return |
4c79579b DA |
1927 | * * < 0 if any input argument is invalid |
1928 | * * 0 on success (packet is forwarded, nexthop neighbor exists) | |
1929 | * * > 0 one of **BPF_FIB_LKUP_RET_** codes explaining why the | |
2bae79d2 | 1930 | * packet is not forwarded or needs assist from full stack |
81110384 JF |
1931 | * |
1932 | * int bpf_sock_hash_update(struct bpf_sock_ops_kern *skops, struct bpf_map *map, void *key, u64 flags) | |
1933 | * Description | |
1934 | * Add an entry to, or update a sockhash *map* referencing sockets. | |
1935 | * The *skops* is used as a new value for the entry associated to | |
1936 | * *key*. *flags* is one of: | |
1937 | * | |
1938 | * **BPF_NOEXIST** | |
1939 | * The entry for *key* must not exist in the map. | |
1940 | * **BPF_EXIST** | |
1941 | * The entry for *key* must already exist in the map. | |
1942 | * **BPF_ANY** | |
1943 | * No condition on the existence of the entry for *key*. | |
1944 | * | |
1945 | * If the *map* has eBPF programs (parser and verdict), those will | |
1946 | * be inherited by the socket being added. If the socket is | |
1947 | * already attached to eBPF programs, this results in an error. | |
1948 | * Return | |
1949 | * 0 on success, or a negative error in case of failure. | |
1950 | * | |
1951 | * int bpf_msg_redirect_hash(struct sk_msg_buff *msg, struct bpf_map *map, void *key, u64 flags) | |
1952 | * Description | |
1953 | * This helper is used in programs implementing policies at the | |
1954 | * socket level. If the message *msg* is allowed to pass (i.e. if | |
1955 | * the verdict eBPF program returns **SK_PASS**), redirect it to | |
1956 | * the socket referenced by *map* (of type | |
1957 | * **BPF_MAP_TYPE_SOCKHASH**) using hash *key*. Both ingress and | |
1958 | * egress interfaces can be used for redirection. The | |
1959 | * **BPF_F_INGRESS** value in *flags* is used to make the | |
1960 | * distinction (ingress path is selected if the flag is present, | |
1961 | * egress path otherwise). This is the only flag supported for now. | |
1962 | * Return | |
1963 | * **SK_PASS** on success, or **SK_DROP** on error. | |
1964 | * | |
1965 | * int bpf_sk_redirect_hash(struct sk_buff *skb, struct bpf_map *map, void *key, u64 flags) | |
1966 | * Description | |
1967 | * This helper is used in programs implementing policies at the | |
1968 | * skb socket level. If the sk_buff *skb* is allowed to pass (i.e. | |
1969 | * if the verdeict eBPF program returns **SK_PASS**), redirect it | |
1970 | * to the socket referenced by *map* (of type | |
1971 | * **BPF_MAP_TYPE_SOCKHASH**) using hash *key*. Both ingress and | |
1972 | * egress interfaces can be used for redirection. The | |
1973 | * **BPF_F_INGRESS** value in *flags* is used to make the | |
1974 | * distinction (ingress path is selected if the flag is present, | |
1975 | * egress otherwise). This is the only flag supported for now. | |
1976 | * Return | |
1977 | * **SK_PASS** on success, or **SK_DROP** on error. | |
fe94cc29 MX |
1978 | * |
1979 | * int bpf_lwt_push_encap(struct sk_buff *skb, u32 type, void *hdr, u32 len) | |
1980 | * Description | |
1981 | * Encapsulate the packet associated to *skb* within a Layer 3 | |
1982 | * protocol header. This header is provided in the buffer at | |
1983 | * address *hdr*, with *len* its size in bytes. *type* indicates | |
1984 | * the protocol of the header and can be one of: | |
1985 | * | |
1986 | * **BPF_LWT_ENCAP_SEG6** | |
1987 | * IPv6 encapsulation with Segment Routing Header | |
1988 | * (**struct ipv6_sr_hdr**). *hdr* only contains the SRH, | |
1989 | * the IPv6 header is computed by the kernel. | |
1990 | * **BPF_LWT_ENCAP_SEG6_INLINE** | |
1991 | * Only works if *skb* contains an IPv6 packet. Insert a | |
1992 | * Segment Routing Header (**struct ipv6_sr_hdr**) inside | |
1993 | * the IPv6 header. | |
1994 | * | |
1995 | * A call to this helper is susceptible to change the underlaying | |
1996 | * packet buffer. Therefore, at load time, all checks on pointers | |
1997 | * previously done by the verifier are invalidated and must be | |
1998 | * performed again, if the helper is used in combination with | |
1999 | * direct packet access. | |
2000 | * Return | |
2001 | * 0 on success, or a negative error in case of failure. | |
2002 | * | |
2003 | * int bpf_lwt_seg6_store_bytes(struct sk_buff *skb, u32 offset, const void *from, u32 len) | |
2004 | * Description | |
2005 | * Store *len* bytes from address *from* into the packet | |
2006 | * associated to *skb*, at *offset*. Only the flags, tag and TLVs | |
2007 | * inside the outermost IPv6 Segment Routing Header can be | |
2008 | * modified through this helper. | |
2009 | * | |
2010 | * A call to this helper is susceptible to change the underlaying | |
2011 | * packet buffer. Therefore, at load time, all checks on pointers | |
2012 | * previously done by the verifier are invalidated and must be | |
2013 | * performed again, if the helper is used in combination with | |
2014 | * direct packet access. | |
2015 | * Return | |
2016 | * 0 on success, or a negative error in case of failure. | |
2017 | * | |
2018 | * int bpf_lwt_seg6_adjust_srh(struct sk_buff *skb, u32 offset, s32 delta) | |
2019 | * Description | |
2020 | * Adjust the size allocated to TLVs in the outermost IPv6 | |
2021 | * Segment Routing Header contained in the packet associated to | |
2022 | * *skb*, at position *offset* by *delta* bytes. Only offsets | |
2023 | * after the segments are accepted. *delta* can be as well | |
2024 | * positive (growing) as negative (shrinking). | |
2025 | * | |
2026 | * A call to this helper is susceptible to change the underlaying | |
2027 | * packet buffer. Therefore, at load time, all checks on pointers | |
2028 | * previously done by the verifier are invalidated and must be | |
2029 | * performed again, if the helper is used in combination with | |
2030 | * direct packet access. | |
2031 | * Return | |
2032 | * 0 on success, or a negative error in case of failure. | |
2033 | * | |
2034 | * int bpf_lwt_seg6_action(struct sk_buff *skb, u32 action, void *param, u32 param_len) | |
2035 | * Description | |
2036 | * Apply an IPv6 Segment Routing action of type *action* to the | |
2037 | * packet associated to *skb*. Each action takes a parameter | |
2038 | * contained at address *param*, and of length *param_len* bytes. | |
2039 | * *action* can be one of: | |
2040 | * | |
2041 | * **SEG6_LOCAL_ACTION_END_X** | |
2042 | * End.X action: Endpoint with Layer-3 cross-connect. | |
2043 | * Type of *param*: **struct in6_addr**. | |
2044 | * **SEG6_LOCAL_ACTION_END_T** | |
2045 | * End.T action: Endpoint with specific IPv6 table lookup. | |
2046 | * Type of *param*: **int**. | |
2047 | * **SEG6_LOCAL_ACTION_END_B6** | |
2048 | * End.B6 action: Endpoint bound to an SRv6 policy. | |
2049 | * Type of param: **struct ipv6_sr_hdr**. | |
2050 | * **SEG6_LOCAL_ACTION_END_B6_ENCAP** | |
2051 | * End.B6.Encap action: Endpoint bound to an SRv6 | |
2052 | * encapsulation policy. | |
2053 | * Type of param: **struct ipv6_sr_hdr**. | |
2054 | * | |
2055 | * A call to this helper is susceptible to change the underlaying | |
2056 | * packet buffer. Therefore, at load time, all checks on pointers | |
2057 | * previously done by the verifier are invalidated and must be | |
2058 | * performed again, if the helper is used in combination with | |
2059 | * direct packet access. | |
2060 | * Return | |
2061 | * 0 on success, or a negative error in case of failure. | |
f4364dcf SY |
2062 | * |
2063 | * int bpf_rc_keydown(void *ctx, u32 protocol, u64 scancode, u32 toggle) | |
2064 | * Description | |
2065 | * This helper is used in programs implementing IR decoding, to | |
2066 | * report a successfully decoded key press with *scancode*, | |
2067 | * *toggle* value in the given *protocol*. The scancode will be | |
2068 | * translated to a keycode using the rc keymap, and reported as | |
2069 | * an input key down event. After a period a key up event is | |
2070 | * generated. This period can be extended by calling either | |
2071 | * **bpf_rc_keydown** () again with the same values, or calling | |
2072 | * **bpf_rc_repeat** (). | |
2073 | * | |
2074 | * Some protocols include a toggle bit, in case the button was | |
2075 | * released and pressed again between consecutive scancodes. | |
2076 | * | |
2077 | * The *ctx* should point to the lirc sample as passed into | |
2078 | * the program. | |
2079 | * | |
2080 | * The *protocol* is the decoded protocol number (see | |
2081 | * **enum rc_proto** for some predefined values). | |
2082 | * | |
2083 | * This helper is only available is the kernel was compiled with | |
2084 | * the **CONFIG_BPF_LIRC_MODE2** configuration option set to | |
2085 | * "**y**". | |
f4364dcf SY |
2086 | * Return |
2087 | * 0 | |
2088 | * | |
2089 | * int bpf_rc_repeat(void *ctx) | |
2090 | * Description | |
2091 | * This helper is used in programs implementing IR decoding, to | |
2092 | * report a successfully decoded repeat key message. This delays | |
2093 | * the generation of a key up event for previously generated | |
2094 | * key down event. | |
2095 | * | |
2096 | * Some IR protocols like NEC have a special IR message for | |
2097 | * repeating last button, for when a button is held down. | |
2098 | * | |
2099 | * The *ctx* should point to the lirc sample as passed into | |
2100 | * the program. | |
2101 | * | |
2102 | * This helper is only available is the kernel was compiled with | |
2103 | * the **CONFIG_BPF_LIRC_MODE2** configuration option set to | |
2104 | * "**y**". | |
f4364dcf SY |
2105 | * Return |
2106 | * 0 | |
cb20b08e DB |
2107 | * |
2108 | * uint64_t bpf_skb_cgroup_id(struct sk_buff *skb) | |
2109 | * Description | |
2110 | * Return the cgroup v2 id of the socket associated with the *skb*. | |
2111 | * This is roughly similar to the **bpf_get_cgroup_classid**\ () | |
2112 | * helper for cgroup v1 by providing a tag resp. identifier that | |
2113 | * can be matched on or used for map lookups e.g. to implement | |
2114 | * policy. The cgroup v2 id of a given path in the hierarchy is | |
2115 | * exposed in user space through the f_handle API in order to get | |
2116 | * to the same 64-bit id. | |
2117 | * | |
2118 | * This helper can be used on TC egress path, but not on ingress, | |
2119 | * and is available only if the kernel was compiled with the | |
2120 | * **CONFIG_SOCK_CGROUP_DATA** configuration option. | |
2121 | * Return | |
2122 | * The id is returned or 0 in case the id could not be retrieved. | |
bf6fa2c8 | 2123 | * |
77236281 AI |
2124 | * u64 bpf_skb_ancestor_cgroup_id(struct sk_buff *skb, int ancestor_level) |
2125 | * Description | |
2126 | * Return id of cgroup v2 that is ancestor of cgroup associated | |
2127 | * with the *skb* at the *ancestor_level*. The root cgroup is at | |
2128 | * *ancestor_level* zero and each step down the hierarchy | |
2129 | * increments the level. If *ancestor_level* == level of cgroup | |
2130 | * associated with *skb*, then return value will be same as that | |
2131 | * of **bpf_skb_cgroup_id**\ (). | |
2132 | * | |
2133 | * The helper is useful to implement policies based on cgroups | |
2134 | * that are upper in hierarchy than immediate cgroup associated | |
2135 | * with *skb*. | |
2136 | * | |
2137 | * The format of returned id and helper limitations are same as in | |
2138 | * **bpf_skb_cgroup_id**\ (). | |
2139 | * Return | |
2140 | * The id is returned or 0 in case the id could not be retrieved. | |
2141 | * | |
bf6fa2c8 YS |
2142 | * u64 bpf_get_current_cgroup_id(void) |
2143 | * Return | |
2144 | * A 64-bit integer containing the current cgroup id based | |
2145 | * on the cgroup within which the current task is running. | |
cd339431 RG |
2146 | * |
2147 | * void* get_local_storage(void *map, u64 flags) | |
2148 | * Description | |
2149 | * Get the pointer to the local storage area. | |
2150 | * The type and the size of the local storage is defined | |
2151 | * by the *map* argument. | |
2152 | * The *flags* meaning is specific for each map type, | |
2153 | * and has to be 0 for cgroup local storage. | |
2154 | * | |
2155 | * Depending on the bpf program type, a local storage area | |
2156 | * can be shared between multiple instances of the bpf program, | |
2157 | * running simultaneously. | |
2158 | * | |
2159 | * A user should care about the synchronization by himself. | |
2160 | * For example, by using the BPF_STX_XADD instruction to alter | |
2161 | * the shared data. | |
2162 | * Return | |
2163 | * Pointer to the local storage area. | |
2dbb9b9e MKL |
2164 | * |
2165 | * int bpf_sk_select_reuseport(struct sk_reuseport_md *reuse, struct bpf_map *map, void *key, u64 flags) | |
2166 | * Description | |
2167 | * Select a SO_REUSEPORT sk from a BPF_MAP_TYPE_REUSEPORT_ARRAY map | |
2168 | * It checks the selected sk is matching the incoming | |
2169 | * request in the skb. | |
2170 | * Return | |
2171 | * 0 on success, or a negative error in case of failure. | |
6acc9b43 | 2172 | * |
f71c6143 | 2173 | * struct bpf_sock *bpf_sk_lookup_tcp(void *ctx, struct bpf_sock_tuple *tuple, u32 tuple_size, u64 netns, u64 flags) |
6acc9b43 JS |
2174 | * Description |
2175 | * Look for TCP socket matching *tuple*, optionally in a child | |
2176 | * network namespace *netns*. The return value must be checked, | |
2177 | * and if non-NULL, released via **bpf_sk_release**\ (). | |
2178 | * | |
2179 | * The *ctx* should point to the context of the program, such as | |
2180 | * the skb or socket (depending on the hook in use). This is used | |
2181 | * to determine the base network namespace for the lookup. | |
2182 | * | |
2183 | * *tuple_size* must be one of: | |
2184 | * | |
2185 | * **sizeof**\ (*tuple*\ **->ipv4**) | |
2186 | * Look for an IPv4 socket. | |
2187 | * **sizeof**\ (*tuple*\ **->ipv6**) | |
2188 | * Look for an IPv6 socket. | |
2189 | * | |
f71c6143 JS |
2190 | * If the *netns* is a negative signed 32-bit integer, then the |
2191 | * socket lookup table in the netns associated with the *ctx* will | |
2192 | * will be used. For the TC hooks, this is the netns of the device | |
2193 | * in the skb. For socket hooks, this is the netns of the socket. | |
2194 | * If *netns* is any other signed 32-bit value greater than or | |
2195 | * equal to zero then it specifies the ID of the netns relative to | |
2196 | * the netns associated with the *ctx*. *netns* values beyond the | |
2197 | * range of 32-bit integers are reserved for future use. | |
6acc9b43 JS |
2198 | * |
2199 | * All values for *flags* are reserved for future usage, and must | |
2200 | * be left at zero. | |
2201 | * | |
2202 | * This helper is available only if the kernel was compiled with | |
2203 | * **CONFIG_NET** configuration option. | |
2204 | * Return | |
2205 | * Pointer to *struct bpf_sock*, or NULL in case of failure. | |
2206 | * | |
f71c6143 | 2207 | * struct bpf_sock *bpf_sk_lookup_udp(void *ctx, struct bpf_sock_tuple *tuple, u32 tuple_size, u64 netns, u64 flags) |
6acc9b43 JS |
2208 | * Description |
2209 | * Look for UDP socket matching *tuple*, optionally in a child | |
2210 | * network namespace *netns*. The return value must be checked, | |
2211 | * and if non-NULL, released via **bpf_sk_release**\ (). | |
2212 | * | |
2213 | * The *ctx* should point to the context of the program, such as | |
2214 | * the skb or socket (depending on the hook in use). This is used | |
2215 | * to determine the base network namespace for the lookup. | |
2216 | * | |
2217 | * *tuple_size* must be one of: | |
2218 | * | |
2219 | * **sizeof**\ (*tuple*\ **->ipv4**) | |
2220 | * Look for an IPv4 socket. | |
2221 | * **sizeof**\ (*tuple*\ **->ipv6**) | |
2222 | * Look for an IPv6 socket. | |
2223 | * | |
f71c6143 JS |
2224 | * If the *netns* is a negative signed 32-bit integer, then the |
2225 | * socket lookup table in the netns associated with the *ctx* will | |
2226 | * will be used. For the TC hooks, this is the netns of the device | |
2227 | * in the skb. For socket hooks, this is the netns of the socket. | |
2228 | * If *netns* is any other signed 32-bit value greater than or | |
2229 | * equal to zero then it specifies the ID of the netns relative to | |
2230 | * the netns associated with the *ctx*. *netns* values beyond the | |
2231 | * range of 32-bit integers are reserved for future use. | |
6acc9b43 JS |
2232 | * |
2233 | * All values for *flags* are reserved for future usage, and must | |
2234 | * be left at zero. | |
2235 | * | |
2236 | * This helper is available only if the kernel was compiled with | |
2237 | * **CONFIG_NET** configuration option. | |
2238 | * Return | |
2239 | * Pointer to *struct bpf_sock*, or NULL in case of failure. | |
2240 | * | |
2241 | * int bpf_sk_release(struct bpf_sock *sk) | |
2242 | * Description | |
2243 | * Release the reference held by *sock*. *sock* must be a non-NULL | |
2244 | * pointer that was returned from bpf_sk_lookup_xxx\ (). | |
2245 | * Return | |
2246 | * 0 on success, or a negative error in case of failure. | |
6fff607e JF |
2247 | * |
2248 | * int bpf_msg_push_data(struct sk_buff *skb, u32 start, u32 len, u64 flags) | |
2249 | * Description | |
2250 | * For socket policies, insert *len* bytes into msg at offset | |
2251 | * *start*. | |
2252 | * | |
2253 | * If a program of type **BPF_PROG_TYPE_SK_MSG** is run on a | |
2254 | * *msg* it may want to insert metadata or options into the msg. | |
2255 | * This can later be read and used by any of the lower layer BPF | |
2256 | * hooks. | |
2257 | * | |
2258 | * This helper may fail if under memory pressure (a malloc | |
2259 | * fails) in these cases BPF programs will get an appropriate | |
2260 | * error and BPF programs will need to handle them. | |
2261 | * | |
2262 | * Return | |
2263 | * 0 on success, or a negative error in case of failure. | |
ebb676da TG |
2264 | */ |
2265 | #define __BPF_FUNC_MAPPER(FN) \ | |
2266 | FN(unspec), \ | |
2267 | FN(map_lookup_elem), \ | |
2268 | FN(map_update_elem), \ | |
2269 | FN(map_delete_elem), \ | |
2270 | FN(probe_read), \ | |
2271 | FN(ktime_get_ns), \ | |
2272 | FN(trace_printk), \ | |
2273 | FN(get_prandom_u32), \ | |
2274 | FN(get_smp_processor_id), \ | |
2275 | FN(skb_store_bytes), \ | |
2276 | FN(l3_csum_replace), \ | |
2277 | FN(l4_csum_replace), \ | |
2278 | FN(tail_call), \ | |
2279 | FN(clone_redirect), \ | |
2280 | FN(get_current_pid_tgid), \ | |
2281 | FN(get_current_uid_gid), \ | |
2282 | FN(get_current_comm), \ | |
2283 | FN(get_cgroup_classid), \ | |
2284 | FN(skb_vlan_push), \ | |
2285 | FN(skb_vlan_pop), \ | |
2286 | FN(skb_get_tunnel_key), \ | |
2287 | FN(skb_set_tunnel_key), \ | |
2288 | FN(perf_event_read), \ | |
2289 | FN(redirect), \ | |
2290 | FN(get_route_realm), \ | |
2291 | FN(perf_event_output), \ | |
2292 | FN(skb_load_bytes), \ | |
2293 | FN(get_stackid), \ | |
2294 | FN(csum_diff), \ | |
2295 | FN(skb_get_tunnel_opt), \ | |
2296 | FN(skb_set_tunnel_opt), \ | |
2297 | FN(skb_change_proto), \ | |
2298 | FN(skb_change_type), \ | |
2299 | FN(skb_under_cgroup), \ | |
2300 | FN(get_hash_recalc), \ | |
2301 | FN(get_current_task), \ | |
2302 | FN(probe_write_user), \ | |
2303 | FN(current_task_under_cgroup), \ | |
2304 | FN(skb_change_tail), \ | |
2305 | FN(skb_pull_data), \ | |
2306 | FN(csum_update), \ | |
2307 | FN(set_hash_invalid), \ | |
3a0af8fd | 2308 | FN(get_numa_node_id), \ |
17bedab2 | 2309 | FN(skb_change_head), \ |
a5e8c070 | 2310 | FN(xdp_adjust_head), \ |
91b8270f | 2311 | FN(probe_read_str), \ |
6acc5c29 | 2312 | FN(get_socket_cookie), \ |
ded092cd | 2313 | FN(get_socket_uid), \ |
8c4b4c7e | 2314 | FN(set_hash), \ |
2be7e212 | 2315 | FN(setsockopt), \ |
97f91a7c | 2316 | FN(skb_adjust_room), \ |
174a79ff JF |
2317 | FN(redirect_map), \ |
2318 | FN(sk_redirect_map), \ | |
2319 | FN(sock_map_update), \ | |
908432ca | 2320 | FN(xdp_adjust_meta), \ |
4bebdc7a | 2321 | FN(perf_event_read_value), \ |
cd86d1fd | 2322 | FN(perf_prog_read_value), \ |
9802d865 | 2323 | FN(getsockopt), \ |
b13d8807 | 2324 | FN(override_return), \ |
4f738adb | 2325 | FN(sock_ops_cb_flags_set), \ |
2a100317 | 2326 | FN(msg_redirect_map), \ |
91843d54 | 2327 | FN(msg_apply_bytes), \ |
015632bb | 2328 | FN(msg_cork_bytes), \ |
d74bad4e | 2329 | FN(msg_pull_data), \ |
b32cc5b9 | 2330 | FN(bind), \ |
12bed760 | 2331 | FN(xdp_adjust_tail), \ |
c195651e | 2332 | FN(skb_get_xfrm_state), \ |
4e1ec56c | 2333 | FN(get_stack), \ |
87f5fc7e | 2334 | FN(skb_load_bytes_relative), \ |
81110384 JF |
2335 | FN(fib_lookup), \ |
2336 | FN(sock_hash_update), \ | |
2337 | FN(msg_redirect_hash), \ | |
fe94cc29 MX |
2338 | FN(sk_redirect_hash), \ |
2339 | FN(lwt_push_encap), \ | |
2340 | FN(lwt_seg6_store_bytes), \ | |
2341 | FN(lwt_seg6_adjust_srh), \ | |
f4364dcf SY |
2342 | FN(lwt_seg6_action), \ |
2343 | FN(rc_repeat), \ | |
cb20b08e | 2344 | FN(rc_keydown), \ |
bf6fa2c8 | 2345 | FN(skb_cgroup_id), \ |
cd339431 | 2346 | FN(get_current_cgroup_id), \ |
2dbb9b9e | 2347 | FN(get_local_storage), \ |
77236281 | 2348 | FN(sk_select_reuseport), \ |
6acc9b43 JS |
2349 | FN(skb_ancestor_cgroup_id), \ |
2350 | FN(sk_lookup_tcp), \ | |
2351 | FN(sk_lookup_udp), \ | |
f1a2e44a MV |
2352 | FN(sk_release), \ |
2353 | FN(map_push_elem), \ | |
2354 | FN(map_pop_elem), \ | |
6fff607e JF |
2355 | FN(map_peek_elem), \ |
2356 | FN(msg_push_data), | |
ebb676da | 2357 | |
09756af4 AS |
2358 | /* integer value in 'imm' field of BPF_CALL instruction selects which helper |
2359 | * function eBPF program intends to call | |
2360 | */ | |
ebb676da | 2361 | #define __BPF_ENUM_FN(x) BPF_FUNC_ ## x |
09756af4 | 2362 | enum bpf_func_id { |
ebb676da | 2363 | __BPF_FUNC_MAPPER(__BPF_ENUM_FN) |
09756af4 AS |
2364 | __BPF_FUNC_MAX_ID, |
2365 | }; | |
ebb676da | 2366 | #undef __BPF_ENUM_FN |
09756af4 | 2367 | |
781c53bc DB |
2368 | /* All flags used by eBPF helper functions, placed here. */ |
2369 | ||
2370 | /* BPF_FUNC_skb_store_bytes flags. */ | |
2371 | #define BPF_F_RECOMPUTE_CSUM (1ULL << 0) | |
8afd54c8 | 2372 | #define BPF_F_INVALIDATE_HASH (1ULL << 1) |
781c53bc DB |
2373 | |
2374 | /* BPF_FUNC_l3_csum_replace and BPF_FUNC_l4_csum_replace flags. | |
2375 | * First 4 bits are for passing the header field size. | |
2376 | */ | |
2377 | #define BPF_F_HDR_FIELD_MASK 0xfULL | |
2378 | ||
2379 | /* BPF_FUNC_l4_csum_replace flags. */ | |
2380 | #define BPF_F_PSEUDO_HDR (1ULL << 4) | |
2f72959a | 2381 | #define BPF_F_MARK_MANGLED_0 (1ULL << 5) |
d1b662ad | 2382 | #define BPF_F_MARK_ENFORCE (1ULL << 6) |
781c53bc DB |
2383 | |
2384 | /* BPF_FUNC_clone_redirect and BPF_FUNC_redirect flags. */ | |
2385 | #define BPF_F_INGRESS (1ULL << 0) | |
2386 | ||
c6c33454 DB |
2387 | /* BPF_FUNC_skb_set_tunnel_key and BPF_FUNC_skb_get_tunnel_key flags. */ |
2388 | #define BPF_F_TUNINFO_IPV6 (1ULL << 0) | |
2389 | ||
c195651e | 2390 | /* flags for both BPF_FUNC_get_stackid and BPF_FUNC_get_stack. */ |
d5a3b1f6 AS |
2391 | #define BPF_F_SKIP_FIELD_MASK 0xffULL |
2392 | #define BPF_F_USER_STACK (1ULL << 8) | |
c195651e | 2393 | /* flags used by BPF_FUNC_get_stackid only. */ |
d5a3b1f6 AS |
2394 | #define BPF_F_FAST_STACK_CMP (1ULL << 9) |
2395 | #define BPF_F_REUSE_STACKID (1ULL << 10) | |
c195651e YS |
2396 | /* flags used by BPF_FUNC_get_stack only. */ |
2397 | #define BPF_F_USER_BUILD_ID (1ULL << 11) | |
d5a3b1f6 | 2398 | |
2da897e5 DB |
2399 | /* BPF_FUNC_skb_set_tunnel_key flags. */ |
2400 | #define BPF_F_ZERO_CSUM_TX (1ULL << 1) | |
22080870 | 2401 | #define BPF_F_DONT_FRAGMENT (1ULL << 2) |
77a5196a | 2402 | #define BPF_F_SEQ_NUMBER (1ULL << 3) |
2da897e5 | 2403 | |
908432ca YS |
2404 | /* BPF_FUNC_perf_event_output, BPF_FUNC_perf_event_read and |
2405 | * BPF_FUNC_perf_event_read_value flags. | |
2406 | */ | |
1e33759c DB |
2407 | #define BPF_F_INDEX_MASK 0xffffffffULL |
2408 | #define BPF_F_CURRENT_CPU BPF_F_INDEX_MASK | |
555c8a86 DB |
2409 | /* BPF_FUNC_perf_event_output for sk_buff input context. */ |
2410 | #define BPF_F_CTXLEN_MASK (0xfffffULL << 32) | |
1e33759c | 2411 | |
f71c6143 JS |
2412 | /* Current network namespace */ |
2413 | #define BPF_F_CURRENT_NETNS (-1L) | |
2414 | ||
2be7e212 DB |
2415 | /* Mode for BPF_FUNC_skb_adjust_room helper. */ |
2416 | enum bpf_adj_room_mode { | |
2417 | BPF_ADJ_ROOM_NET, | |
2418 | }; | |
2419 | ||
4e1ec56c DB |
2420 | /* Mode for BPF_FUNC_skb_load_bytes_relative helper. */ |
2421 | enum bpf_hdr_start_off { | |
2422 | BPF_HDR_START_MAC, | |
2423 | BPF_HDR_START_NET, | |
2424 | }; | |
2425 | ||
fe94cc29 MX |
2426 | /* Encapsulation type for BPF_FUNC_lwt_push_encap helper. */ |
2427 | enum bpf_lwt_encap_mode { | |
2428 | BPF_LWT_ENCAP_SEG6, | |
2429 | BPF_LWT_ENCAP_SEG6_INLINE | |
2430 | }; | |
2431 | ||
b7df9ada DB |
2432 | #define __bpf_md_ptr(type, name) \ |
2433 | union { \ | |
2434 | type name; \ | |
2435 | __u64 :64; \ | |
2436 | } __attribute__((aligned(8))) | |
2437 | ||
9bac3d6d AS |
2438 | /* user accessible mirror of in-kernel sk_buff. |
2439 | * new fields can only be added to the end of this structure | |
2440 | */ | |
2441 | struct __sk_buff { | |
2442 | __u32 len; | |
2443 | __u32 pkt_type; | |
2444 | __u32 mark; | |
2445 | __u32 queue_mapping; | |
c2497395 AS |
2446 | __u32 protocol; |
2447 | __u32 vlan_present; | |
2448 | __u32 vlan_tci; | |
27cd5452 | 2449 | __u32 vlan_proto; |
bcad5718 | 2450 | __u32 priority; |
37e82c2f AS |
2451 | __u32 ingress_ifindex; |
2452 | __u32 ifindex; | |
d691f9e8 AS |
2453 | __u32 tc_index; |
2454 | __u32 cb[5]; | |
ba7591d8 | 2455 | __u32 hash; |
045efa82 | 2456 | __u32 tc_classid; |
969bf05e AS |
2457 | __u32 data; |
2458 | __u32 data_end; | |
b1d9fc41 | 2459 | __u32 napi_id; |
8a31db56 | 2460 | |
de8f3a83 | 2461 | /* Accessed by BPF_PROG_TYPE_sk_skb types from here to ... */ |
8a31db56 JF |
2462 | __u32 family; |
2463 | __u32 remote_ip4; /* Stored in network byte order */ | |
2464 | __u32 local_ip4; /* Stored in network byte order */ | |
2465 | __u32 remote_ip6[4]; /* Stored in network byte order */ | |
2466 | __u32 local_ip6[4]; /* Stored in network byte order */ | |
2467 | __u32 remote_port; /* Stored in network byte order */ | |
2468 | __u32 local_port; /* stored in host byte order */ | |
de8f3a83 DB |
2469 | /* ... here. */ |
2470 | ||
2471 | __u32 data_meta; | |
b7df9ada | 2472 | __bpf_md_ptr(struct bpf_flow_keys *, flow_keys); |
9bac3d6d AS |
2473 | }; |
2474 | ||
d3aa45ce AS |
2475 | struct bpf_tunnel_key { |
2476 | __u32 tunnel_id; | |
c6c33454 DB |
2477 | union { |
2478 | __u32 remote_ipv4; | |
2479 | __u32 remote_ipv6[4]; | |
2480 | }; | |
2481 | __u8 tunnel_tos; | |
2482 | __u8 tunnel_ttl; | |
1fbc2e0c | 2483 | __u16 tunnel_ext; /* Padding, future use. */ |
4018ab18 | 2484 | __u32 tunnel_label; |
d3aa45ce AS |
2485 | }; |
2486 | ||
12bed760 EB |
2487 | /* user accessible mirror of in-kernel xfrm_state. |
2488 | * new fields can only be added to the end of this structure | |
2489 | */ | |
2490 | struct bpf_xfrm_state { | |
2491 | __u32 reqid; | |
2492 | __u32 spi; /* Stored in network byte order */ | |
2493 | __u16 family; | |
1fbc2e0c | 2494 | __u16 ext; /* Padding, future use. */ |
12bed760 EB |
2495 | union { |
2496 | __u32 remote_ipv4; /* Stored in network byte order */ | |
2497 | __u32 remote_ipv6[4]; /* Stored in network byte order */ | |
2498 | }; | |
2499 | }; | |
2500 | ||
3a0af8fd TG |
2501 | /* Generic BPF return codes which all BPF program types may support. |
2502 | * The values are binary compatible with their TC_ACT_* counter-part to | |
2503 | * provide backwards compatibility with existing SCHED_CLS and SCHED_ACT | |
2504 | * programs. | |
2505 | * | |
2506 | * XDP is handled seprately, see XDP_*. | |
2507 | */ | |
2508 | enum bpf_ret_code { | |
2509 | BPF_OK = 0, | |
2510 | /* 1 reserved */ | |
2511 | BPF_DROP = 2, | |
2512 | /* 3-6 reserved */ | |
2513 | BPF_REDIRECT = 7, | |
2514 | /* >127 are reserved for prog type specific return codes */ | |
2515 | }; | |
2516 | ||
61023658 DA |
2517 | struct bpf_sock { |
2518 | __u32 bound_dev_if; | |
aa4c1037 DA |
2519 | __u32 family; |
2520 | __u32 type; | |
2521 | __u32 protocol; | |
482dca93 DA |
2522 | __u32 mark; |
2523 | __u32 priority; | |
aac3fc32 AI |
2524 | __u32 src_ip4; /* Allows 1,2,4-byte read. |
2525 | * Stored in network byte order. | |
2526 | */ | |
2527 | __u32 src_ip6[4]; /* Allows 1,2,4-byte read. | |
2528 | * Stored in network byte order. | |
2529 | */ | |
2530 | __u32 src_port; /* Allows 4-byte read. | |
2531 | * Stored in host byte order | |
2532 | */ | |
61023658 DA |
2533 | }; |
2534 | ||
6acc9b43 JS |
2535 | struct bpf_sock_tuple { |
2536 | union { | |
2537 | struct { | |
2538 | __be32 saddr; | |
2539 | __be32 daddr; | |
2540 | __be16 sport; | |
2541 | __be16 dport; | |
2542 | } ipv4; | |
2543 | struct { | |
2544 | __be32 saddr[4]; | |
2545 | __be32 daddr[4]; | |
2546 | __be16 sport; | |
2547 | __be16 dport; | |
2548 | } ipv6; | |
2549 | }; | |
2550 | }; | |
2551 | ||
17bedab2 MKL |
2552 | #define XDP_PACKET_HEADROOM 256 |
2553 | ||
6a773a15 BB |
2554 | /* User return codes for XDP prog type. |
2555 | * A valid XDP program must return one of these defined values. All other | |
9beb8bed DB |
2556 | * return codes are reserved for future use. Unknown return codes will |
2557 | * result in packet drops and a warning via bpf_warn_invalid_xdp_action(). | |
6a773a15 BB |
2558 | */ |
2559 | enum xdp_action { | |
2560 | XDP_ABORTED = 0, | |
2561 | XDP_DROP, | |
2562 | XDP_PASS, | |
6ce96ca3 | 2563 | XDP_TX, |
814abfab | 2564 | XDP_REDIRECT, |
6a773a15 BB |
2565 | }; |
2566 | ||
2567 | /* user accessible metadata for XDP packet hook | |
2568 | * new fields must be added to the end of this structure | |
2569 | */ | |
2570 | struct xdp_md { | |
2571 | __u32 data; | |
2572 | __u32 data_end; | |
de8f3a83 | 2573 | __u32 data_meta; |
daaf24c6 | 2574 | /* Below access go through struct xdp_rxq_info */ |
02dd3291 JDB |
2575 | __u32 ingress_ifindex; /* rxq->dev->ifindex */ |
2576 | __u32 rx_queue_index; /* rxq->queue_index */ | |
6a773a15 BB |
2577 | }; |
2578 | ||
174a79ff | 2579 | enum sk_action { |
bfa64075 JF |
2580 | SK_DROP = 0, |
2581 | SK_PASS, | |
174a79ff JF |
2582 | }; |
2583 | ||
4f738adb JF |
2584 | /* user accessible metadata for SK_MSG packet hook, new fields must |
2585 | * be added to the end of this structure | |
2586 | */ | |
2587 | struct sk_msg_md { | |
b7df9ada DB |
2588 | __bpf_md_ptr(void *, data); |
2589 | __bpf_md_ptr(void *, data_end); | |
303def35 JF |
2590 | |
2591 | __u32 family; | |
2592 | __u32 remote_ip4; /* Stored in network byte order */ | |
2593 | __u32 local_ip4; /* Stored in network byte order */ | |
2594 | __u32 remote_ip6[4]; /* Stored in network byte order */ | |
2595 | __u32 local_ip6[4]; /* Stored in network byte order */ | |
2596 | __u32 remote_port; /* Stored in network byte order */ | |
2597 | __u32 local_port; /* stored in host byte order */ | |
4f738adb JF |
2598 | }; |
2599 | ||
2dbb9b9e MKL |
2600 | struct sk_reuseport_md { |
2601 | /* | |
2602 | * Start of directly accessible data. It begins from | |
2603 | * the tcp/udp header. | |
2604 | */ | |
b7df9ada DB |
2605 | __bpf_md_ptr(void *, data); |
2606 | /* End of directly accessible data */ | |
2607 | __bpf_md_ptr(void *, data_end); | |
2dbb9b9e MKL |
2608 | /* |
2609 | * Total length of packet (starting from the tcp/udp header). | |
2610 | * Note that the directly accessible bytes (data_end - data) | |
2611 | * could be less than this "len". Those bytes could be | |
2612 | * indirectly read by a helper "bpf_skb_load_bytes()". | |
2613 | */ | |
2614 | __u32 len; | |
2615 | /* | |
2616 | * Eth protocol in the mac header (network byte order). e.g. | |
2617 | * ETH_P_IP(0x0800) and ETH_P_IPV6(0x86DD) | |
2618 | */ | |
2619 | __u32 eth_protocol; | |
2620 | __u32 ip_protocol; /* IP protocol. e.g. IPPROTO_TCP, IPPROTO_UDP */ | |
2621 | __u32 bind_inany; /* Is sock bound to an INANY address? */ | |
2622 | __u32 hash; /* A hash of the packet 4 tuples */ | |
2623 | }; | |
2624 | ||
1e270976 MKL |
2625 | #define BPF_TAG_SIZE 8 |
2626 | ||
2627 | struct bpf_prog_info { | |
2628 | __u32 type; | |
2629 | __u32 id; | |
2630 | __u8 tag[BPF_TAG_SIZE]; | |
2631 | __u32 jited_prog_len; | |
2632 | __u32 xlated_prog_len; | |
2633 | __aligned_u64 jited_prog_insns; | |
2634 | __aligned_u64 xlated_prog_insns; | |
cb4d2b3f MKL |
2635 | __u64 load_time; /* ns since boottime */ |
2636 | __u32 created_by_uid; | |
2637 | __u32 nr_map_ids; | |
2638 | __aligned_u64 map_ids; | |
067cae47 | 2639 | char name[BPF_OBJ_NAME_LEN]; |
675fc275 | 2640 | __u32 ifindex; |
b85fab0e | 2641 | __u32 gpl_compatible:1; |
675fc275 JK |
2642 | __u64 netns_dev; |
2643 | __u64 netns_ino; | |
dbecd738 | 2644 | __u32 nr_jited_ksyms; |
815581c1 | 2645 | __u32 nr_jited_func_lens; |
dbecd738 | 2646 | __aligned_u64 jited_ksyms; |
815581c1 | 2647 | __aligned_u64 jited_func_lens; |
1e270976 MKL |
2648 | } __attribute__((aligned(8))); |
2649 | ||
2650 | struct bpf_map_info { | |
2651 | __u32 type; | |
2652 | __u32 id; | |
2653 | __u32 key_size; | |
2654 | __u32 value_size; | |
2655 | __u32 max_entries; | |
2656 | __u32 map_flags; | |
067cae47 | 2657 | char name[BPF_OBJ_NAME_LEN]; |
52775b33 | 2658 | __u32 ifindex; |
36f9814a | 2659 | __u32 :32; |
52775b33 JK |
2660 | __u64 netns_dev; |
2661 | __u64 netns_ino; | |
78958fca | 2662 | __u32 btf_id; |
9b2cf328 MKL |
2663 | __u32 btf_key_type_id; |
2664 | __u32 btf_value_type_id; | |
1e270976 MKL |
2665 | } __attribute__((aligned(8))); |
2666 | ||
62dab84c MKL |
2667 | struct bpf_btf_info { |
2668 | __aligned_u64 btf; | |
2669 | __u32 btf_size; | |
2670 | __u32 id; | |
2671 | } __attribute__((aligned(8))); | |
2672 | ||
4fbac77d AI |
2673 | /* User bpf_sock_addr struct to access socket fields and sockaddr struct passed |
2674 | * by user and intended to be used by socket (e.g. to bind to, depends on | |
2675 | * attach attach type). | |
2676 | */ | |
2677 | struct bpf_sock_addr { | |
2678 | __u32 user_family; /* Allows 4-byte read, but no write. */ | |
2679 | __u32 user_ip4; /* Allows 1,2,4-byte read and 4-byte write. | |
2680 | * Stored in network byte order. | |
2681 | */ | |
2682 | __u32 user_ip6[4]; /* Allows 1,2,4-byte read an 4-byte write. | |
2683 | * Stored in network byte order. | |
2684 | */ | |
2685 | __u32 user_port; /* Allows 4-byte read and write. | |
2686 | * Stored in network byte order | |
2687 | */ | |
2688 | __u32 family; /* Allows 4-byte read, but no write */ | |
2689 | __u32 type; /* Allows 4-byte read, but no write */ | |
2690 | __u32 protocol; /* Allows 4-byte read, but no write */ | |
1cedee13 AI |
2691 | __u32 msg_src_ip4; /* Allows 1,2,4-byte read an 4-byte write. |
2692 | * Stored in network byte order. | |
2693 | */ | |
2694 | __u32 msg_src_ip6[4]; /* Allows 1,2,4-byte read an 4-byte write. | |
2695 | * Stored in network byte order. | |
2696 | */ | |
4fbac77d AI |
2697 | }; |
2698 | ||
40304b2a LB |
2699 | /* User bpf_sock_ops struct to access socket values and specify request ops |
2700 | * and their replies. | |
2701 | * Some of this fields are in network (bigendian) byte order and may need | |
2702 | * to be converted before use (bpf_ntohl() defined in samples/bpf/bpf_endian.h). | |
2703 | * New fields can only be added at the end of this structure | |
2704 | */ | |
2705 | struct bpf_sock_ops { | |
2706 | __u32 op; | |
2707 | union { | |
de525be2 LB |
2708 | __u32 args[4]; /* Optionally passed to bpf program */ |
2709 | __u32 reply; /* Returned by bpf program */ | |
2710 | __u32 replylong[4]; /* Optionally returned by bpf prog */ | |
40304b2a LB |
2711 | }; |
2712 | __u32 family; | |
2713 | __u32 remote_ip4; /* Stored in network byte order */ | |
2714 | __u32 local_ip4; /* Stored in network byte order */ | |
2715 | __u32 remote_ip6[4]; /* Stored in network byte order */ | |
2716 | __u32 local_ip6[4]; /* Stored in network byte order */ | |
2717 | __u32 remote_port; /* Stored in network byte order */ | |
2718 | __u32 local_port; /* stored in host byte order */ | |
f19397a5 LB |
2719 | __u32 is_fullsock; /* Some TCP fields are only valid if |
2720 | * there is a full socket. If not, the | |
2721 | * fields read as zero. | |
2722 | */ | |
2723 | __u32 snd_cwnd; | |
2724 | __u32 srtt_us; /* Averaged RTT << 3 in usecs */ | |
b13d8807 | 2725 | __u32 bpf_sock_ops_cb_flags; /* flags defined in uapi/linux/tcp.h */ |
44f0e430 LB |
2726 | __u32 state; |
2727 | __u32 rtt_min; | |
2728 | __u32 snd_ssthresh; | |
2729 | __u32 rcv_nxt; | |
2730 | __u32 snd_nxt; | |
2731 | __u32 snd_una; | |
2732 | __u32 mss_cache; | |
2733 | __u32 ecn_flags; | |
2734 | __u32 rate_delivered; | |
2735 | __u32 rate_interval_us; | |
2736 | __u32 packets_out; | |
2737 | __u32 retrans_out; | |
2738 | __u32 total_retrans; | |
2739 | __u32 segs_in; | |
2740 | __u32 data_segs_in; | |
2741 | __u32 segs_out; | |
2742 | __u32 data_segs_out; | |
2743 | __u32 lost_out; | |
2744 | __u32 sacked_out; | |
2745 | __u32 sk_txhash; | |
2746 | __u64 bytes_received; | |
2747 | __u64 bytes_acked; | |
40304b2a LB |
2748 | }; |
2749 | ||
b13d8807 | 2750 | /* Definitions for bpf_sock_ops_cb_flags */ |
f89013f6 | 2751 | #define BPF_SOCK_OPS_RTO_CB_FLAG (1<<0) |
a31ad29e | 2752 | #define BPF_SOCK_OPS_RETRANS_CB_FLAG (1<<1) |
d4487491 LB |
2753 | #define BPF_SOCK_OPS_STATE_CB_FLAG (1<<2) |
2754 | #define BPF_SOCK_OPS_ALL_CB_FLAGS 0x7 /* Mask of all currently | |
b13d8807 LB |
2755 | * supported cb flags |
2756 | */ | |
2757 | ||
40304b2a LB |
2758 | /* List of known BPF sock_ops operators. |
2759 | * New entries can only be added at the end | |
2760 | */ | |
2761 | enum { | |
2762 | BPF_SOCK_OPS_VOID, | |
8550f328 LB |
2763 | BPF_SOCK_OPS_TIMEOUT_INIT, /* Should return SYN-RTO value to use or |
2764 | * -1 if default value should be used | |
2765 | */ | |
13d3b1eb LB |
2766 | BPF_SOCK_OPS_RWND_INIT, /* Should return initial advertized |
2767 | * window (in packets) or -1 if default | |
2768 | * value should be used | |
2769 | */ | |
9872a4bd LB |
2770 | BPF_SOCK_OPS_TCP_CONNECT_CB, /* Calls BPF program right before an |
2771 | * active connection is initialized | |
2772 | */ | |
2773 | BPF_SOCK_OPS_ACTIVE_ESTABLISHED_CB, /* Calls BPF program when an | |
2774 | * active connection is | |
2775 | * established | |
2776 | */ | |
2777 | BPF_SOCK_OPS_PASSIVE_ESTABLISHED_CB, /* Calls BPF program when a | |
2778 | * passive connection is | |
2779 | * established | |
2780 | */ | |
91b5b21c LB |
2781 | BPF_SOCK_OPS_NEEDS_ECN, /* If connection's congestion control |
2782 | * needs ECN | |
2783 | */ | |
e6546ef6 LB |
2784 | BPF_SOCK_OPS_BASE_RTT, /* Get base RTT. The correct value is |
2785 | * based on the path and may be | |
2786 | * dependent on the congestion control | |
2787 | * algorithm. In general it indicates | |
2788 | * a congestion threshold. RTTs above | |
2789 | * this indicate congestion | |
2790 | */ | |
f89013f6 LB |
2791 | BPF_SOCK_OPS_RTO_CB, /* Called when an RTO has triggered. |
2792 | * Arg1: value of icsk_retransmits | |
2793 | * Arg2: value of icsk_rto | |
2794 | * Arg3: whether RTO has expired | |
2795 | */ | |
a31ad29e LB |
2796 | BPF_SOCK_OPS_RETRANS_CB, /* Called when skb is retransmitted. |
2797 | * Arg1: sequence number of 1st byte | |
2798 | * Arg2: # segments | |
2799 | * Arg3: return value of | |
2800 | * tcp_transmit_skb (0 => success) | |
2801 | */ | |
d4487491 LB |
2802 | BPF_SOCK_OPS_STATE_CB, /* Called when TCP changes state. |
2803 | * Arg1: old_state | |
2804 | * Arg2: new_state | |
2805 | */ | |
f333ee0c AI |
2806 | BPF_SOCK_OPS_TCP_LISTEN_CB, /* Called on listen(2), right after |
2807 | * socket transition to LISTEN state. | |
2808 | */ | |
d4487491 LB |
2809 | }; |
2810 | ||
2811 | /* List of TCP states. There is a build check in net/ipv4/tcp.c to detect | |
2812 | * changes between the TCP and BPF versions. Ideally this should never happen. | |
2813 | * If it does, we need to add code to convert them before calling | |
2814 | * the BPF sock_ops function. | |
2815 | */ | |
2816 | enum { | |
2817 | BPF_TCP_ESTABLISHED = 1, | |
2818 | BPF_TCP_SYN_SENT, | |
2819 | BPF_TCP_SYN_RECV, | |
2820 | BPF_TCP_FIN_WAIT1, | |
2821 | BPF_TCP_FIN_WAIT2, | |
2822 | BPF_TCP_TIME_WAIT, | |
2823 | BPF_TCP_CLOSE, | |
2824 | BPF_TCP_CLOSE_WAIT, | |
2825 | BPF_TCP_LAST_ACK, | |
2826 | BPF_TCP_LISTEN, | |
2827 | BPF_TCP_CLOSING, /* Now a valid state */ | |
2828 | BPF_TCP_NEW_SYN_RECV, | |
2829 | ||
2830 | BPF_TCP_MAX_STATES /* Leave at the end! */ | |
40304b2a LB |
2831 | }; |
2832 | ||
fc747810 | 2833 | #define TCP_BPF_IW 1001 /* Set TCP initial congestion window */ |
13bf9641 | 2834 | #define TCP_BPF_SNDCWND_CLAMP 1002 /* Set sndcwnd_clamp */ |
fc747810 | 2835 | |
908432ca YS |
2836 | struct bpf_perf_event_value { |
2837 | __u64 counter; | |
2838 | __u64 enabled; | |
2839 | __u64 running; | |
2840 | }; | |
2841 | ||
ebc614f6 RG |
2842 | #define BPF_DEVCG_ACC_MKNOD (1ULL << 0) |
2843 | #define BPF_DEVCG_ACC_READ (1ULL << 1) | |
2844 | #define BPF_DEVCG_ACC_WRITE (1ULL << 2) | |
2845 | ||
2846 | #define BPF_DEVCG_DEV_BLOCK (1ULL << 0) | |
2847 | #define BPF_DEVCG_DEV_CHAR (1ULL << 1) | |
2848 | ||
2849 | struct bpf_cgroup_dev_ctx { | |
06ef0ccb YS |
2850 | /* access_type encoded as (BPF_DEVCG_ACC_* << 16) | BPF_DEVCG_DEV_* */ |
2851 | __u32 access_type; | |
ebc614f6 RG |
2852 | __u32 major; |
2853 | __u32 minor; | |
2854 | }; | |
2855 | ||
c4f6699d AS |
2856 | struct bpf_raw_tracepoint_args { |
2857 | __u64 args[0]; | |
2858 | }; | |
2859 | ||
87f5fc7e DA |
2860 | /* DIRECT: Skip the FIB rules and go to FIB table associated with device |
2861 | * OUTPUT: Do lookup from egress perspective; default is ingress | |
2862 | */ | |
2863 | #define BPF_FIB_LOOKUP_DIRECT BIT(0) | |
2864 | #define BPF_FIB_LOOKUP_OUTPUT BIT(1) | |
2865 | ||
4c79579b DA |
2866 | enum { |
2867 | BPF_FIB_LKUP_RET_SUCCESS, /* lookup successful */ | |
2868 | BPF_FIB_LKUP_RET_BLACKHOLE, /* dest is blackholed; can be dropped */ | |
2869 | BPF_FIB_LKUP_RET_UNREACHABLE, /* dest is unreachable; can be dropped */ | |
2870 | BPF_FIB_LKUP_RET_PROHIBIT, /* dest not allowed; can be dropped */ | |
2871 | BPF_FIB_LKUP_RET_NOT_FWDED, /* packet is not forwarded */ | |
2872 | BPF_FIB_LKUP_RET_FWD_DISABLED, /* fwding is not enabled on ingress */ | |
2873 | BPF_FIB_LKUP_RET_UNSUPP_LWT, /* fwd requires encapsulation */ | |
2874 | BPF_FIB_LKUP_RET_NO_NEIGH, /* no neighbor entry for nh */ | |
2875 | BPF_FIB_LKUP_RET_FRAG_NEEDED, /* fragmentation required to fwd */ | |
2876 | }; | |
2877 | ||
87f5fc7e | 2878 | struct bpf_fib_lookup { |
fa898d76 DA |
2879 | /* input: network family for lookup (AF_INET, AF_INET6) |
2880 | * output: network family of egress nexthop | |
2881 | */ | |
2882 | __u8 family; | |
87f5fc7e DA |
2883 | |
2884 | /* set if lookup is to consider L4 data - e.g., FIB rules */ | |
2885 | __u8 l4_protocol; | |
2886 | __be16 sport; | |
2887 | __be16 dport; | |
2888 | ||
2889 | /* total length of packet from network header - used for MTU check */ | |
2890 | __u16 tot_len; | |
4c79579b DA |
2891 | |
2892 | /* input: L3 device index for lookup | |
2893 | * output: device index from FIB lookup | |
2894 | */ | |
2895 | __u32 ifindex; | |
87f5fc7e DA |
2896 | |
2897 | union { | |
2898 | /* inputs to lookup */ | |
2899 | __u8 tos; /* AF_INET */ | |
bd3a08aa | 2900 | __be32 flowinfo; /* AF_INET6, flow_label + priority */ |
87f5fc7e | 2901 | |
fa898d76 DA |
2902 | /* output: metric of fib result (IPv4/IPv6 only) */ |
2903 | __u32 rt_metric; | |
87f5fc7e DA |
2904 | }; |
2905 | ||
2906 | union { | |
87f5fc7e DA |
2907 | __be32 ipv4_src; |
2908 | __u32 ipv6_src[4]; /* in6_addr; network order */ | |
2909 | }; | |
2910 | ||
fa898d76 DA |
2911 | /* input to bpf_fib_lookup, ipv{4,6}_dst is destination address in |
2912 | * network header. output: bpf_fib_lookup sets to gateway address | |
2913 | * if FIB lookup returns gateway route | |
87f5fc7e DA |
2914 | */ |
2915 | union { | |
87f5fc7e DA |
2916 | __be32 ipv4_dst; |
2917 | __u32 ipv6_dst[4]; /* in6_addr; network order */ | |
2918 | }; | |
2919 | ||
2920 | /* output */ | |
2921 | __be16 h_vlan_proto; | |
2922 | __be16 h_vlan_TCI; | |
2923 | __u8 smac[6]; /* ETH_ALEN */ | |
2924 | __u8 dmac[6]; /* ETH_ALEN */ | |
2925 | }; | |
2926 | ||
41bdc4b4 YS |
2927 | enum bpf_task_fd_type { |
2928 | BPF_FD_TYPE_RAW_TRACEPOINT, /* tp name */ | |
2929 | BPF_FD_TYPE_TRACEPOINT, /* tp name */ | |
2930 | BPF_FD_TYPE_KPROBE, /* (symbol + offset) or addr */ | |
2931 | BPF_FD_TYPE_KRETPROBE, /* (symbol + offset) or addr */ | |
2932 | BPF_FD_TYPE_UPROBE, /* filename + offset */ | |
2933 | BPF_FD_TYPE_URETPROBE, /* filename + offset */ | |
2934 | }; | |
2935 | ||
d58e468b PP |
2936 | struct bpf_flow_keys { |
2937 | __u16 nhoff; | |
2938 | __u16 thoff; | |
2939 | __u16 addr_proto; /* ETH_P_* of valid addrs */ | |
2940 | __u8 is_frag; | |
2941 | __u8 is_first_frag; | |
2942 | __u8 is_encap; | |
2943 | __u8 ip_proto; | |
2944 | __be16 n_proto; | |
2945 | __be16 sport; | |
2946 | __be16 dport; | |
2947 | union { | |
2948 | struct { | |
2949 | __be32 ipv4_src; | |
2950 | __be32 ipv4_dst; | |
2951 | }; | |
2952 | struct { | |
2953 | __u32 ipv6_src[4]; /* in6_addr; network order */ | |
2954 | __u32 ipv6_dst[4]; /* in6_addr; network order */ | |
2955 | }; | |
2956 | }; | |
2957 | }; | |
2958 | ||
daedfb22 | 2959 | #endif /* _UAPI__LINUX_BPF_H__ */ |