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Merge branch 'pm-cpufreq-sched'
[thirdparty/kernel/stable.git] / include / linux / filter.h
1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3 * Linux Socket Filter Data Structures
4 */
5 #ifndef __LINUX_FILTER_H__
6 #define __LINUX_FILTER_H__
7
8 #include <stdarg.h>
9
10 #include <linux/atomic.h>
11 #include <linux/refcount.h>
12 #include <linux/compat.h>
13 #include <linux/skbuff.h>
14 #include <linux/linkage.h>
15 #include <linux/printk.h>
16 #include <linux/workqueue.h>
17 #include <linux/sched.h>
18 #include <linux/capability.h>
19 #include <linux/cryptohash.h>
20 #include <linux/set_memory.h>
21
22 #include <net/sch_generic.h>
23
24 #include <uapi/linux/filter.h>
25 #include <uapi/linux/bpf.h>
26
27 struct sk_buff;
28 struct sock;
29 struct seccomp_data;
30 struct bpf_prog_aux;
31
32 /* ArgX, context and stack frame pointer register positions. Note,
33 * Arg1, Arg2, Arg3, etc are used as argument mappings of function
34 * calls in BPF_CALL instruction.
35 */
36 #define BPF_REG_ARG1 BPF_REG_1
37 #define BPF_REG_ARG2 BPF_REG_2
38 #define BPF_REG_ARG3 BPF_REG_3
39 #define BPF_REG_ARG4 BPF_REG_4
40 #define BPF_REG_ARG5 BPF_REG_5
41 #define BPF_REG_CTX BPF_REG_6
42 #define BPF_REG_FP BPF_REG_10
43
44 /* Additional register mappings for converted user programs. */
45 #define BPF_REG_A BPF_REG_0
46 #define BPF_REG_X BPF_REG_7
47 #define BPF_REG_TMP BPF_REG_8
48
49 /* Kernel hidden auxiliary/helper register for hardening step.
50 * Only used by eBPF JITs. It's nothing more than a temporary
51 * register that JITs use internally, only that here it's part
52 * of eBPF instructions that have been rewritten for blinding
53 * constants. See JIT pre-step in bpf_jit_blind_constants().
54 */
55 #define BPF_REG_AX MAX_BPF_REG
56 #define MAX_BPF_JIT_REG (MAX_BPF_REG + 1)
57
58 /* unused opcode to mark special call to bpf_tail_call() helper */
59 #define BPF_TAIL_CALL 0xf0
60
61 /* As per nm, we expose JITed images as text (code) section for
62 * kallsyms. That way, tools like perf can find it to match
63 * addresses.
64 */
65 #define BPF_SYM_ELF_TYPE 't'
66
67 /* BPF program can access up to 512 bytes of stack space. */
68 #define MAX_BPF_STACK 512
69
70 /* Helper macros for filter block array initializers. */
71
72 /* ALU ops on registers, bpf_add|sub|...: dst_reg += src_reg */
73
74 #define BPF_ALU64_REG(OP, DST, SRC) \
75 ((struct bpf_insn) { \
76 .code = BPF_ALU64 | BPF_OP(OP) | BPF_X, \
77 .dst_reg = DST, \
78 .src_reg = SRC, \
79 .off = 0, \
80 .imm = 0 })
81
82 #define BPF_ALU32_REG(OP, DST, SRC) \
83 ((struct bpf_insn) { \
84 .code = BPF_ALU | BPF_OP(OP) | BPF_X, \
85 .dst_reg = DST, \
86 .src_reg = SRC, \
87 .off = 0, \
88 .imm = 0 })
89
90 /* ALU ops on immediates, bpf_add|sub|...: dst_reg += imm32 */
91
92 #define BPF_ALU64_IMM(OP, DST, IMM) \
93 ((struct bpf_insn) { \
94 .code = BPF_ALU64 | BPF_OP(OP) | BPF_K, \
95 .dst_reg = DST, \
96 .src_reg = 0, \
97 .off = 0, \
98 .imm = IMM })
99
100 #define BPF_ALU32_IMM(OP, DST, IMM) \
101 ((struct bpf_insn) { \
102 .code = BPF_ALU | BPF_OP(OP) | BPF_K, \
103 .dst_reg = DST, \
104 .src_reg = 0, \
105 .off = 0, \
106 .imm = IMM })
107
108 /* Endianess conversion, cpu_to_{l,b}e(), {l,b}e_to_cpu() */
109
110 #define BPF_ENDIAN(TYPE, DST, LEN) \
111 ((struct bpf_insn) { \
112 .code = BPF_ALU | BPF_END | BPF_SRC(TYPE), \
113 .dst_reg = DST, \
114 .src_reg = 0, \
115 .off = 0, \
116 .imm = LEN })
117
118 /* Short form of mov, dst_reg = src_reg */
119
120 #define BPF_MOV64_REG(DST, SRC) \
121 ((struct bpf_insn) { \
122 .code = BPF_ALU64 | BPF_MOV | BPF_X, \
123 .dst_reg = DST, \
124 .src_reg = SRC, \
125 .off = 0, \
126 .imm = 0 })
127
128 #define BPF_MOV32_REG(DST, SRC) \
129 ((struct bpf_insn) { \
130 .code = BPF_ALU | BPF_MOV | BPF_X, \
131 .dst_reg = DST, \
132 .src_reg = SRC, \
133 .off = 0, \
134 .imm = 0 })
135
136 /* Short form of mov, dst_reg = imm32 */
137
138 #define BPF_MOV64_IMM(DST, IMM) \
139 ((struct bpf_insn) { \
140 .code = BPF_ALU64 | BPF_MOV | BPF_K, \
141 .dst_reg = DST, \
142 .src_reg = 0, \
143 .off = 0, \
144 .imm = IMM })
145
146 #define BPF_MOV32_IMM(DST, IMM) \
147 ((struct bpf_insn) { \
148 .code = BPF_ALU | BPF_MOV | BPF_K, \
149 .dst_reg = DST, \
150 .src_reg = 0, \
151 .off = 0, \
152 .imm = IMM })
153
154 /* BPF_LD_IMM64 macro encodes single 'load 64-bit immediate' insn */
155 #define BPF_LD_IMM64(DST, IMM) \
156 BPF_LD_IMM64_RAW(DST, 0, IMM)
157
158 #define BPF_LD_IMM64_RAW(DST, SRC, IMM) \
159 ((struct bpf_insn) { \
160 .code = BPF_LD | BPF_DW | BPF_IMM, \
161 .dst_reg = DST, \
162 .src_reg = SRC, \
163 .off = 0, \
164 .imm = (__u32) (IMM) }), \
165 ((struct bpf_insn) { \
166 .code = 0, /* zero is reserved opcode */ \
167 .dst_reg = 0, \
168 .src_reg = 0, \
169 .off = 0, \
170 .imm = ((__u64) (IMM)) >> 32 })
171
172 /* pseudo BPF_LD_IMM64 insn used to refer to process-local map_fd */
173 #define BPF_LD_MAP_FD(DST, MAP_FD) \
174 BPF_LD_IMM64_RAW(DST, BPF_PSEUDO_MAP_FD, MAP_FD)
175
176 /* Short form of mov based on type, BPF_X: dst_reg = src_reg, BPF_K: dst_reg = imm32 */
177
178 #define BPF_MOV64_RAW(TYPE, DST, SRC, IMM) \
179 ((struct bpf_insn) { \
180 .code = BPF_ALU64 | BPF_MOV | BPF_SRC(TYPE), \
181 .dst_reg = DST, \
182 .src_reg = SRC, \
183 .off = 0, \
184 .imm = IMM })
185
186 #define BPF_MOV32_RAW(TYPE, DST, SRC, IMM) \
187 ((struct bpf_insn) { \
188 .code = BPF_ALU | BPF_MOV | BPF_SRC(TYPE), \
189 .dst_reg = DST, \
190 .src_reg = SRC, \
191 .off = 0, \
192 .imm = IMM })
193
194 /* Direct packet access, R0 = *(uint *) (skb->data + imm32) */
195
196 #define BPF_LD_ABS(SIZE, IMM) \
197 ((struct bpf_insn) { \
198 .code = BPF_LD | BPF_SIZE(SIZE) | BPF_ABS, \
199 .dst_reg = 0, \
200 .src_reg = 0, \
201 .off = 0, \
202 .imm = IMM })
203
204 /* Indirect packet access, R0 = *(uint *) (skb->data + src_reg + imm32) */
205
206 #define BPF_LD_IND(SIZE, SRC, IMM) \
207 ((struct bpf_insn) { \
208 .code = BPF_LD | BPF_SIZE(SIZE) | BPF_IND, \
209 .dst_reg = 0, \
210 .src_reg = SRC, \
211 .off = 0, \
212 .imm = IMM })
213
214 /* Memory load, dst_reg = *(uint *) (src_reg + off16) */
215
216 #define BPF_LDX_MEM(SIZE, DST, SRC, OFF) \
217 ((struct bpf_insn) { \
218 .code = BPF_LDX | BPF_SIZE(SIZE) | BPF_MEM, \
219 .dst_reg = DST, \
220 .src_reg = SRC, \
221 .off = OFF, \
222 .imm = 0 })
223
224 /* Memory store, *(uint *) (dst_reg + off16) = src_reg */
225
226 #define BPF_STX_MEM(SIZE, DST, SRC, OFF) \
227 ((struct bpf_insn) { \
228 .code = BPF_STX | BPF_SIZE(SIZE) | BPF_MEM, \
229 .dst_reg = DST, \
230 .src_reg = SRC, \
231 .off = OFF, \
232 .imm = 0 })
233
234 /* Atomic memory add, *(uint *)(dst_reg + off16) += src_reg */
235
236 #define BPF_STX_XADD(SIZE, DST, SRC, OFF) \
237 ((struct bpf_insn) { \
238 .code = BPF_STX | BPF_SIZE(SIZE) | BPF_XADD, \
239 .dst_reg = DST, \
240 .src_reg = SRC, \
241 .off = OFF, \
242 .imm = 0 })
243
244 /* Memory store, *(uint *) (dst_reg + off16) = imm32 */
245
246 #define BPF_ST_MEM(SIZE, DST, OFF, IMM) \
247 ((struct bpf_insn) { \
248 .code = BPF_ST | BPF_SIZE(SIZE) | BPF_MEM, \
249 .dst_reg = DST, \
250 .src_reg = 0, \
251 .off = OFF, \
252 .imm = IMM })
253
254 /* Conditional jumps against registers, if (dst_reg 'op' src_reg) goto pc + off16 */
255
256 #define BPF_JMP_REG(OP, DST, SRC, OFF) \
257 ((struct bpf_insn) { \
258 .code = BPF_JMP | BPF_OP(OP) | BPF_X, \
259 .dst_reg = DST, \
260 .src_reg = SRC, \
261 .off = OFF, \
262 .imm = 0 })
263
264 /* Conditional jumps against immediates, if (dst_reg 'op' imm32) goto pc + off16 */
265
266 #define BPF_JMP_IMM(OP, DST, IMM, OFF) \
267 ((struct bpf_insn) { \
268 .code = BPF_JMP | BPF_OP(OP) | BPF_K, \
269 .dst_reg = DST, \
270 .src_reg = 0, \
271 .off = OFF, \
272 .imm = IMM })
273
274 /* Unconditional jumps, goto pc + off16 */
275
276 #define BPF_JMP_A(OFF) \
277 ((struct bpf_insn) { \
278 .code = BPF_JMP | BPF_JA, \
279 .dst_reg = 0, \
280 .src_reg = 0, \
281 .off = OFF, \
282 .imm = 0 })
283
284 /* Function call */
285
286 #define BPF_EMIT_CALL(FUNC) \
287 ((struct bpf_insn) { \
288 .code = BPF_JMP | BPF_CALL, \
289 .dst_reg = 0, \
290 .src_reg = 0, \
291 .off = 0, \
292 .imm = ((FUNC) - __bpf_call_base) })
293
294 /* Raw code statement block */
295
296 #define BPF_RAW_INSN(CODE, DST, SRC, OFF, IMM) \
297 ((struct bpf_insn) { \
298 .code = CODE, \
299 .dst_reg = DST, \
300 .src_reg = SRC, \
301 .off = OFF, \
302 .imm = IMM })
303
304 /* Program exit */
305
306 #define BPF_EXIT_INSN() \
307 ((struct bpf_insn) { \
308 .code = BPF_JMP | BPF_EXIT, \
309 .dst_reg = 0, \
310 .src_reg = 0, \
311 .off = 0, \
312 .imm = 0 })
313
314 /* Internal classic blocks for direct assignment */
315
316 #define __BPF_STMT(CODE, K) \
317 ((struct sock_filter) BPF_STMT(CODE, K))
318
319 #define __BPF_JUMP(CODE, K, JT, JF) \
320 ((struct sock_filter) BPF_JUMP(CODE, K, JT, JF))
321
322 #define bytes_to_bpf_size(bytes) \
323 ({ \
324 int bpf_size = -EINVAL; \
325 \
326 if (bytes == sizeof(u8)) \
327 bpf_size = BPF_B; \
328 else if (bytes == sizeof(u16)) \
329 bpf_size = BPF_H; \
330 else if (bytes == sizeof(u32)) \
331 bpf_size = BPF_W; \
332 else if (bytes == sizeof(u64)) \
333 bpf_size = BPF_DW; \
334 \
335 bpf_size; \
336 })
337
338 #define bpf_size_to_bytes(bpf_size) \
339 ({ \
340 int bytes = -EINVAL; \
341 \
342 if (bpf_size == BPF_B) \
343 bytes = sizeof(u8); \
344 else if (bpf_size == BPF_H) \
345 bytes = sizeof(u16); \
346 else if (bpf_size == BPF_W) \
347 bytes = sizeof(u32); \
348 else if (bpf_size == BPF_DW) \
349 bytes = sizeof(u64); \
350 \
351 bytes; \
352 })
353
354 #define BPF_SIZEOF(type) \
355 ({ \
356 const int __size = bytes_to_bpf_size(sizeof(type)); \
357 BUILD_BUG_ON(__size < 0); \
358 __size; \
359 })
360
361 #define BPF_FIELD_SIZEOF(type, field) \
362 ({ \
363 const int __size = bytes_to_bpf_size(FIELD_SIZEOF(type, field)); \
364 BUILD_BUG_ON(__size < 0); \
365 __size; \
366 })
367
368 #define BPF_LDST_BYTES(insn) \
369 ({ \
370 const int __size = bpf_size_to_bytes(BPF_SIZE(insn->code)); \
371 WARN_ON(__size < 0); \
372 __size; \
373 })
374
375 #define __BPF_MAP_0(m, v, ...) v
376 #define __BPF_MAP_1(m, v, t, a, ...) m(t, a)
377 #define __BPF_MAP_2(m, v, t, a, ...) m(t, a), __BPF_MAP_1(m, v, __VA_ARGS__)
378 #define __BPF_MAP_3(m, v, t, a, ...) m(t, a), __BPF_MAP_2(m, v, __VA_ARGS__)
379 #define __BPF_MAP_4(m, v, t, a, ...) m(t, a), __BPF_MAP_3(m, v, __VA_ARGS__)
380 #define __BPF_MAP_5(m, v, t, a, ...) m(t, a), __BPF_MAP_4(m, v, __VA_ARGS__)
381
382 #define __BPF_REG_0(...) __BPF_PAD(5)
383 #define __BPF_REG_1(...) __BPF_MAP(1, __VA_ARGS__), __BPF_PAD(4)
384 #define __BPF_REG_2(...) __BPF_MAP(2, __VA_ARGS__), __BPF_PAD(3)
385 #define __BPF_REG_3(...) __BPF_MAP(3, __VA_ARGS__), __BPF_PAD(2)
386 #define __BPF_REG_4(...) __BPF_MAP(4, __VA_ARGS__), __BPF_PAD(1)
387 #define __BPF_REG_5(...) __BPF_MAP(5, __VA_ARGS__)
388
389 #define __BPF_MAP(n, ...) __BPF_MAP_##n(__VA_ARGS__)
390 #define __BPF_REG(n, ...) __BPF_REG_##n(__VA_ARGS__)
391
392 #define __BPF_CAST(t, a) \
393 (__force t) \
394 (__force \
395 typeof(__builtin_choose_expr(sizeof(t) == sizeof(unsigned long), \
396 (unsigned long)0, (t)0))) a
397 #define __BPF_V void
398 #define __BPF_N
399
400 #define __BPF_DECL_ARGS(t, a) t a
401 #define __BPF_DECL_REGS(t, a) u64 a
402
403 #define __BPF_PAD(n) \
404 __BPF_MAP(n, __BPF_DECL_ARGS, __BPF_N, u64, __ur_1, u64, __ur_2, \
405 u64, __ur_3, u64, __ur_4, u64, __ur_5)
406
407 #define BPF_CALL_x(x, name, ...) \
408 static __always_inline \
409 u64 ____##name(__BPF_MAP(x, __BPF_DECL_ARGS, __BPF_V, __VA_ARGS__)); \
410 u64 name(__BPF_REG(x, __BPF_DECL_REGS, __BPF_N, __VA_ARGS__)); \
411 u64 name(__BPF_REG(x, __BPF_DECL_REGS, __BPF_N, __VA_ARGS__)) \
412 { \
413 return ____##name(__BPF_MAP(x,__BPF_CAST,__BPF_N,__VA_ARGS__));\
414 } \
415 static __always_inline \
416 u64 ____##name(__BPF_MAP(x, __BPF_DECL_ARGS, __BPF_V, __VA_ARGS__))
417
418 #define BPF_CALL_0(name, ...) BPF_CALL_x(0, name, __VA_ARGS__)
419 #define BPF_CALL_1(name, ...) BPF_CALL_x(1, name, __VA_ARGS__)
420 #define BPF_CALL_2(name, ...) BPF_CALL_x(2, name, __VA_ARGS__)
421 #define BPF_CALL_3(name, ...) BPF_CALL_x(3, name, __VA_ARGS__)
422 #define BPF_CALL_4(name, ...) BPF_CALL_x(4, name, __VA_ARGS__)
423 #define BPF_CALL_5(name, ...) BPF_CALL_x(5, name, __VA_ARGS__)
424
425 #define bpf_ctx_range(TYPE, MEMBER) \
426 offsetof(TYPE, MEMBER) ... offsetofend(TYPE, MEMBER) - 1
427 #define bpf_ctx_range_till(TYPE, MEMBER1, MEMBER2) \
428 offsetof(TYPE, MEMBER1) ... offsetofend(TYPE, MEMBER2) - 1
429
430 #define bpf_target_off(TYPE, MEMBER, SIZE, PTR_SIZE) \
431 ({ \
432 BUILD_BUG_ON(FIELD_SIZEOF(TYPE, MEMBER) != (SIZE)); \
433 *(PTR_SIZE) = (SIZE); \
434 offsetof(TYPE, MEMBER); \
435 })
436
437 #ifdef CONFIG_COMPAT
438 /* A struct sock_filter is architecture independent. */
439 struct compat_sock_fprog {
440 u16 len;
441 compat_uptr_t filter; /* struct sock_filter * */
442 };
443 #endif
444
445 struct sock_fprog_kern {
446 u16 len;
447 struct sock_filter *filter;
448 };
449
450 struct bpf_binary_header {
451 unsigned int pages;
452 u8 image[];
453 };
454
455 struct bpf_prog {
456 u16 pages; /* Number of allocated pages */
457 kmemcheck_bitfield_begin(meta);
458 u16 jited:1, /* Is our filter JIT'ed? */
459 locked:1, /* Program image locked? */
460 gpl_compatible:1, /* Is filter GPL compatible? */
461 cb_access:1, /* Is control block accessed? */
462 dst_needed:1; /* Do we need dst entry? */
463 kmemcheck_bitfield_end(meta);
464 enum bpf_prog_type type; /* Type of BPF program */
465 u32 len; /* Number of filter blocks */
466 u32 jited_len; /* Size of jited insns in bytes */
467 u8 tag[BPF_TAG_SIZE];
468 struct bpf_prog_aux *aux; /* Auxiliary fields */
469 struct sock_fprog_kern *orig_prog; /* Original BPF program */
470 unsigned int (*bpf_func)(const void *ctx,
471 const struct bpf_insn *insn);
472 /* Instructions for interpreter */
473 union {
474 struct sock_filter insns[0];
475 struct bpf_insn insnsi[0];
476 };
477 };
478
479 struct sk_filter {
480 refcount_t refcnt;
481 struct rcu_head rcu;
482 struct bpf_prog *prog;
483 };
484
485 #define BPF_PROG_RUN(filter, ctx) (*filter->bpf_func)(ctx, filter->insnsi)
486
487 #define BPF_SKB_CB_LEN QDISC_CB_PRIV_LEN
488
489 struct bpf_skb_data_end {
490 struct qdisc_skb_cb qdisc_cb;
491 void *data_end;
492 };
493
494 struct xdp_buff {
495 void *data;
496 void *data_end;
497 void *data_hard_start;
498 };
499
500 /* compute the linear packet data range [data, data_end) which
501 * will be accessed by cls_bpf, act_bpf and lwt programs
502 */
503 static inline void bpf_compute_data_end(struct sk_buff *skb)
504 {
505 struct bpf_skb_data_end *cb = (struct bpf_skb_data_end *)skb->cb;
506
507 BUILD_BUG_ON(sizeof(*cb) > FIELD_SIZEOF(struct sk_buff, cb));
508 cb->data_end = skb->data + skb_headlen(skb);
509 }
510
511 static inline u8 *bpf_skb_cb(struct sk_buff *skb)
512 {
513 /* eBPF programs may read/write skb->cb[] area to transfer meta
514 * data between tail calls. Since this also needs to work with
515 * tc, that scratch memory is mapped to qdisc_skb_cb's data area.
516 *
517 * In some socket filter cases, the cb unfortunately needs to be
518 * saved/restored so that protocol specific skb->cb[] data won't
519 * be lost. In any case, due to unpriviledged eBPF programs
520 * attached to sockets, we need to clear the bpf_skb_cb() area
521 * to not leak previous contents to user space.
522 */
523 BUILD_BUG_ON(FIELD_SIZEOF(struct __sk_buff, cb) != BPF_SKB_CB_LEN);
524 BUILD_BUG_ON(FIELD_SIZEOF(struct __sk_buff, cb) !=
525 FIELD_SIZEOF(struct qdisc_skb_cb, data));
526
527 return qdisc_skb_cb(skb)->data;
528 }
529
530 static inline u32 bpf_prog_run_save_cb(const struct bpf_prog *prog,
531 struct sk_buff *skb)
532 {
533 u8 *cb_data = bpf_skb_cb(skb);
534 u8 cb_saved[BPF_SKB_CB_LEN];
535 u32 res;
536
537 if (unlikely(prog->cb_access)) {
538 memcpy(cb_saved, cb_data, sizeof(cb_saved));
539 memset(cb_data, 0, sizeof(cb_saved));
540 }
541
542 res = BPF_PROG_RUN(prog, skb);
543
544 if (unlikely(prog->cb_access))
545 memcpy(cb_data, cb_saved, sizeof(cb_saved));
546
547 return res;
548 }
549
550 static inline u32 bpf_prog_run_clear_cb(const struct bpf_prog *prog,
551 struct sk_buff *skb)
552 {
553 u8 *cb_data = bpf_skb_cb(skb);
554
555 if (unlikely(prog->cb_access))
556 memset(cb_data, 0, BPF_SKB_CB_LEN);
557
558 return BPF_PROG_RUN(prog, skb);
559 }
560
561 static __always_inline u32 bpf_prog_run_xdp(const struct bpf_prog *prog,
562 struct xdp_buff *xdp)
563 {
564 /* Caller needs to hold rcu_read_lock() (!), otherwise program
565 * can be released while still running, or map elements could be
566 * freed early while still having concurrent users. XDP fastpath
567 * already takes rcu_read_lock() when fetching the program, so
568 * it's not necessary here anymore.
569 */
570 return BPF_PROG_RUN(prog, xdp);
571 }
572
573 static inline u32 bpf_prog_insn_size(const struct bpf_prog *prog)
574 {
575 return prog->len * sizeof(struct bpf_insn);
576 }
577
578 static inline u32 bpf_prog_tag_scratch_size(const struct bpf_prog *prog)
579 {
580 return round_up(bpf_prog_insn_size(prog) +
581 sizeof(__be64) + 1, SHA_MESSAGE_BYTES);
582 }
583
584 static inline unsigned int bpf_prog_size(unsigned int proglen)
585 {
586 return max(sizeof(struct bpf_prog),
587 offsetof(struct bpf_prog, insns[proglen]));
588 }
589
590 static inline bool bpf_prog_was_classic(const struct bpf_prog *prog)
591 {
592 /* When classic BPF programs have been loaded and the arch
593 * does not have a classic BPF JIT (anymore), they have been
594 * converted via bpf_migrate_filter() to eBPF and thus always
595 * have an unspec program type.
596 */
597 return prog->type == BPF_PROG_TYPE_UNSPEC;
598 }
599
600 static inline bool
601 bpf_ctx_narrow_access_ok(u32 off, u32 size, const u32 size_default)
602 {
603 bool off_ok;
604 #ifdef __LITTLE_ENDIAN
605 off_ok = (off & (size_default - 1)) == 0;
606 #else
607 off_ok = (off & (size_default - 1)) + size == size_default;
608 #endif
609 return off_ok && size <= size_default && (size & (size - 1)) == 0;
610 }
611
612 #define bpf_classic_proglen(fprog) (fprog->len * sizeof(fprog->filter[0]))
613
614 #ifdef CONFIG_ARCH_HAS_SET_MEMORY
615 static inline void bpf_prog_lock_ro(struct bpf_prog *fp)
616 {
617 fp->locked = 1;
618 WARN_ON_ONCE(set_memory_ro((unsigned long)fp, fp->pages));
619 }
620
621 static inline void bpf_prog_unlock_ro(struct bpf_prog *fp)
622 {
623 if (fp->locked) {
624 WARN_ON_ONCE(set_memory_rw((unsigned long)fp, fp->pages));
625 /* In case set_memory_rw() fails, we want to be the first
626 * to crash here instead of some random place later on.
627 */
628 fp->locked = 0;
629 }
630 }
631
632 static inline void bpf_jit_binary_lock_ro(struct bpf_binary_header *hdr)
633 {
634 WARN_ON_ONCE(set_memory_ro((unsigned long)hdr, hdr->pages));
635 }
636
637 static inline void bpf_jit_binary_unlock_ro(struct bpf_binary_header *hdr)
638 {
639 WARN_ON_ONCE(set_memory_rw((unsigned long)hdr, hdr->pages));
640 }
641 #else
642 static inline void bpf_prog_lock_ro(struct bpf_prog *fp)
643 {
644 }
645
646 static inline void bpf_prog_unlock_ro(struct bpf_prog *fp)
647 {
648 }
649
650 static inline void bpf_jit_binary_lock_ro(struct bpf_binary_header *hdr)
651 {
652 }
653
654 static inline void bpf_jit_binary_unlock_ro(struct bpf_binary_header *hdr)
655 {
656 }
657 #endif /* CONFIG_ARCH_HAS_SET_MEMORY */
658
659 static inline struct bpf_binary_header *
660 bpf_jit_binary_hdr(const struct bpf_prog *fp)
661 {
662 unsigned long real_start = (unsigned long)fp->bpf_func;
663 unsigned long addr = real_start & PAGE_MASK;
664
665 return (void *)addr;
666 }
667
668 int sk_filter_trim_cap(struct sock *sk, struct sk_buff *skb, unsigned int cap);
669 static inline int sk_filter(struct sock *sk, struct sk_buff *skb)
670 {
671 return sk_filter_trim_cap(sk, skb, 1);
672 }
673
674 struct bpf_prog *bpf_prog_select_runtime(struct bpf_prog *fp, int *err);
675 void bpf_prog_free(struct bpf_prog *fp);
676
677 struct bpf_prog *bpf_prog_alloc(unsigned int size, gfp_t gfp_extra_flags);
678 struct bpf_prog *bpf_prog_realloc(struct bpf_prog *fp_old, unsigned int size,
679 gfp_t gfp_extra_flags);
680 void __bpf_prog_free(struct bpf_prog *fp);
681
682 static inline void bpf_prog_unlock_free(struct bpf_prog *fp)
683 {
684 bpf_prog_unlock_ro(fp);
685 __bpf_prog_free(fp);
686 }
687
688 typedef int (*bpf_aux_classic_check_t)(struct sock_filter *filter,
689 unsigned int flen);
690
691 int bpf_prog_create(struct bpf_prog **pfp, struct sock_fprog_kern *fprog);
692 int bpf_prog_create_from_user(struct bpf_prog **pfp, struct sock_fprog *fprog,
693 bpf_aux_classic_check_t trans, bool save_orig);
694 void bpf_prog_destroy(struct bpf_prog *fp);
695
696 int sk_attach_filter(struct sock_fprog *fprog, struct sock *sk);
697 int sk_attach_bpf(u32 ufd, struct sock *sk);
698 int sk_reuseport_attach_filter(struct sock_fprog *fprog, struct sock *sk);
699 int sk_reuseport_attach_bpf(u32 ufd, struct sock *sk);
700 int sk_detach_filter(struct sock *sk);
701 int sk_get_filter(struct sock *sk, struct sock_filter __user *filter,
702 unsigned int len);
703
704 bool sk_filter_charge(struct sock *sk, struct sk_filter *fp);
705 void sk_filter_uncharge(struct sock *sk, struct sk_filter *fp);
706
707 u64 __bpf_call_base(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5);
708
709 struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog);
710 void bpf_jit_compile(struct bpf_prog *prog);
711 bool bpf_helper_changes_pkt_data(void *func);
712
713 struct bpf_prog *bpf_patch_insn_single(struct bpf_prog *prog, u32 off,
714 const struct bpf_insn *patch, u32 len);
715
716 /* The pair of xdp_do_redirect and xdp_do_flush_map MUST be called in the
717 * same cpu context. Further for best results no more than a single map
718 * for the do_redirect/do_flush pair should be used. This limitation is
719 * because we only track one map and force a flush when the map changes.
720 * This does not appear to be a real limitation for existing software.
721 */
722 int xdp_do_generic_redirect(struct net_device *dev, struct sk_buff *skb,
723 struct bpf_prog *prog);
724 int xdp_do_redirect(struct net_device *dev,
725 struct xdp_buff *xdp,
726 struct bpf_prog *prog);
727 void xdp_do_flush_map(void);
728
729 void bpf_warn_invalid_xdp_action(u32 act);
730 void bpf_warn_invalid_xdp_redirect(u32 ifindex);
731
732 struct sock *do_sk_redirect_map(struct sk_buff *skb);
733
734 #ifdef CONFIG_BPF_JIT
735 extern int bpf_jit_enable;
736 extern int bpf_jit_harden;
737 extern int bpf_jit_kallsyms;
738
739 typedef void (*bpf_jit_fill_hole_t)(void *area, unsigned int size);
740
741 struct bpf_binary_header *
742 bpf_jit_binary_alloc(unsigned int proglen, u8 **image_ptr,
743 unsigned int alignment,
744 bpf_jit_fill_hole_t bpf_fill_ill_insns);
745 void bpf_jit_binary_free(struct bpf_binary_header *hdr);
746
747 void bpf_jit_free(struct bpf_prog *fp);
748
749 struct bpf_prog *bpf_jit_blind_constants(struct bpf_prog *fp);
750 void bpf_jit_prog_release_other(struct bpf_prog *fp, struct bpf_prog *fp_other);
751
752 static inline void bpf_jit_dump(unsigned int flen, unsigned int proglen,
753 u32 pass, void *image)
754 {
755 pr_err("flen=%u proglen=%u pass=%u image=%pK from=%s pid=%d\n", flen,
756 proglen, pass, image, current->comm, task_pid_nr(current));
757
758 if (image)
759 print_hex_dump(KERN_ERR, "JIT code: ", DUMP_PREFIX_OFFSET,
760 16, 1, image, proglen, false);
761 }
762
763 static inline bool bpf_jit_is_ebpf(void)
764 {
765 # ifdef CONFIG_HAVE_EBPF_JIT
766 return true;
767 # else
768 return false;
769 # endif
770 }
771
772 static inline bool ebpf_jit_enabled(void)
773 {
774 return bpf_jit_enable && bpf_jit_is_ebpf();
775 }
776
777 static inline bool bpf_prog_ebpf_jited(const struct bpf_prog *fp)
778 {
779 return fp->jited && bpf_jit_is_ebpf();
780 }
781
782 static inline bool bpf_jit_blinding_enabled(void)
783 {
784 /* These are the prerequisites, should someone ever have the
785 * idea to call blinding outside of them, we make sure to
786 * bail out.
787 */
788 if (!bpf_jit_is_ebpf())
789 return false;
790 if (!bpf_jit_enable)
791 return false;
792 if (!bpf_jit_harden)
793 return false;
794 if (bpf_jit_harden == 1 && capable(CAP_SYS_ADMIN))
795 return false;
796
797 return true;
798 }
799
800 static inline bool bpf_jit_kallsyms_enabled(void)
801 {
802 /* There are a couple of corner cases where kallsyms should
803 * not be enabled f.e. on hardening.
804 */
805 if (bpf_jit_harden)
806 return false;
807 if (!bpf_jit_kallsyms)
808 return false;
809 if (bpf_jit_kallsyms == 1)
810 return true;
811
812 return false;
813 }
814
815 const char *__bpf_address_lookup(unsigned long addr, unsigned long *size,
816 unsigned long *off, char *sym);
817 bool is_bpf_text_address(unsigned long addr);
818 int bpf_get_kallsym(unsigned int symnum, unsigned long *value, char *type,
819 char *sym);
820
821 static inline const char *
822 bpf_address_lookup(unsigned long addr, unsigned long *size,
823 unsigned long *off, char **modname, char *sym)
824 {
825 const char *ret = __bpf_address_lookup(addr, size, off, sym);
826
827 if (ret && modname)
828 *modname = NULL;
829 return ret;
830 }
831
832 void bpf_prog_kallsyms_add(struct bpf_prog *fp);
833 void bpf_prog_kallsyms_del(struct bpf_prog *fp);
834
835 #else /* CONFIG_BPF_JIT */
836
837 static inline bool ebpf_jit_enabled(void)
838 {
839 return false;
840 }
841
842 static inline bool bpf_prog_ebpf_jited(const struct bpf_prog *fp)
843 {
844 return false;
845 }
846
847 static inline void bpf_jit_free(struct bpf_prog *fp)
848 {
849 bpf_prog_unlock_free(fp);
850 }
851
852 static inline bool bpf_jit_kallsyms_enabled(void)
853 {
854 return false;
855 }
856
857 static inline const char *
858 __bpf_address_lookup(unsigned long addr, unsigned long *size,
859 unsigned long *off, char *sym)
860 {
861 return NULL;
862 }
863
864 static inline bool is_bpf_text_address(unsigned long addr)
865 {
866 return false;
867 }
868
869 static inline int bpf_get_kallsym(unsigned int symnum, unsigned long *value,
870 char *type, char *sym)
871 {
872 return -ERANGE;
873 }
874
875 static inline const char *
876 bpf_address_lookup(unsigned long addr, unsigned long *size,
877 unsigned long *off, char **modname, char *sym)
878 {
879 return NULL;
880 }
881
882 static inline void bpf_prog_kallsyms_add(struct bpf_prog *fp)
883 {
884 }
885
886 static inline void bpf_prog_kallsyms_del(struct bpf_prog *fp)
887 {
888 }
889 #endif /* CONFIG_BPF_JIT */
890
891 #define BPF_ANC BIT(15)
892
893 static inline bool bpf_needs_clear_a(const struct sock_filter *first)
894 {
895 switch (first->code) {
896 case BPF_RET | BPF_K:
897 case BPF_LD | BPF_W | BPF_LEN:
898 return false;
899
900 case BPF_LD | BPF_W | BPF_ABS:
901 case BPF_LD | BPF_H | BPF_ABS:
902 case BPF_LD | BPF_B | BPF_ABS:
903 if (first->k == SKF_AD_OFF + SKF_AD_ALU_XOR_X)
904 return true;
905 return false;
906
907 default:
908 return true;
909 }
910 }
911
912 static inline u16 bpf_anc_helper(const struct sock_filter *ftest)
913 {
914 BUG_ON(ftest->code & BPF_ANC);
915
916 switch (ftest->code) {
917 case BPF_LD | BPF_W | BPF_ABS:
918 case BPF_LD | BPF_H | BPF_ABS:
919 case BPF_LD | BPF_B | BPF_ABS:
920 #define BPF_ANCILLARY(CODE) case SKF_AD_OFF + SKF_AD_##CODE: \
921 return BPF_ANC | SKF_AD_##CODE
922 switch (ftest->k) {
923 BPF_ANCILLARY(PROTOCOL);
924 BPF_ANCILLARY(PKTTYPE);
925 BPF_ANCILLARY(IFINDEX);
926 BPF_ANCILLARY(NLATTR);
927 BPF_ANCILLARY(NLATTR_NEST);
928 BPF_ANCILLARY(MARK);
929 BPF_ANCILLARY(QUEUE);
930 BPF_ANCILLARY(HATYPE);
931 BPF_ANCILLARY(RXHASH);
932 BPF_ANCILLARY(CPU);
933 BPF_ANCILLARY(ALU_XOR_X);
934 BPF_ANCILLARY(VLAN_TAG);
935 BPF_ANCILLARY(VLAN_TAG_PRESENT);
936 BPF_ANCILLARY(PAY_OFFSET);
937 BPF_ANCILLARY(RANDOM);
938 BPF_ANCILLARY(VLAN_TPID);
939 }
940 /* Fallthrough. */
941 default:
942 return ftest->code;
943 }
944 }
945
946 void *bpf_internal_load_pointer_neg_helper(const struct sk_buff *skb,
947 int k, unsigned int size);
948
949 static inline void *bpf_load_pointer(const struct sk_buff *skb, int k,
950 unsigned int size, void *buffer)
951 {
952 if (k >= 0)
953 return skb_header_pointer(skb, k, size, buffer);
954
955 return bpf_internal_load_pointer_neg_helper(skb, k, size);
956 }
957
958 static inline int bpf_tell_extensions(void)
959 {
960 return SKF_AD_MAX;
961 }
962
963 struct bpf_sock_ops_kern {
964 struct sock *sk;
965 u32 op;
966 union {
967 u32 reply;
968 u32 replylong[4];
969 };
970 };
971
972 #endif /* __LINUX_FILTER_H__ */
Mirror https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git