Line data Source code
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/set_memory.h>
20 : #include <linux/kallsyms.h>
21 : #include <linux/if_vlan.h>
22 : #include <linux/vmalloc.h>
23 : #include <linux/sockptr.h>
24 : #include <crypto/sha1.h>
25 : #include <linux/u64_stats_sync.h>
26 :
27 : #include <net/sch_generic.h>
28 :
29 : #include <asm/byteorder.h>
30 : #include <uapi/linux/filter.h>
31 : #include <uapi/linux/bpf.h>
32 :
33 : struct sk_buff;
34 : struct sock;
35 : struct seccomp_data;
36 : struct bpf_prog_aux;
37 : struct xdp_rxq_info;
38 : struct xdp_buff;
39 : struct sock_reuseport;
40 : struct ctl_table;
41 : struct ctl_table_header;
42 :
43 : /* ArgX, context and stack frame pointer register positions. Note,
44 : * Arg1, Arg2, Arg3, etc are used as argument mappings of function
45 : * calls in BPF_CALL instruction.
46 : */
47 : #define BPF_REG_ARG1 BPF_REG_1
48 : #define BPF_REG_ARG2 BPF_REG_2
49 : #define BPF_REG_ARG3 BPF_REG_3
50 : #define BPF_REG_ARG4 BPF_REG_4
51 : #define BPF_REG_ARG5 BPF_REG_5
52 : #define BPF_REG_CTX BPF_REG_6
53 : #define BPF_REG_FP BPF_REG_10
54 :
55 : /* Additional register mappings for converted user programs. */
56 : #define BPF_REG_A BPF_REG_0
57 : #define BPF_REG_X BPF_REG_7
58 : #define BPF_REG_TMP BPF_REG_2 /* scratch reg */
59 : #define BPF_REG_D BPF_REG_8 /* data, callee-saved */
60 : #define BPF_REG_H BPF_REG_9 /* hlen, callee-saved */
61 :
62 : /* Kernel hidden auxiliary/helper register. */
63 : #define BPF_REG_AX MAX_BPF_REG
64 : #define MAX_BPF_EXT_REG (MAX_BPF_REG + 1)
65 : #define MAX_BPF_JIT_REG MAX_BPF_EXT_REG
66 :
67 : /* unused opcode to mark special call to bpf_tail_call() helper */
68 : #define BPF_TAIL_CALL 0xf0
69 :
70 : /* unused opcode to mark special load instruction. Same as BPF_ABS */
71 : #define BPF_PROBE_MEM 0x20
72 :
73 : /* unused opcode to mark call to interpreter with arguments */
74 : #define BPF_CALL_ARGS 0xe0
75 :
76 : /* As per nm, we expose JITed images as text (code) section for
77 : * kallsyms. That way, tools like perf can find it to match
78 : * addresses.
79 : */
80 : #define BPF_SYM_ELF_TYPE 't'
81 :
82 : /* BPF program can access up to 512 bytes of stack space. */
83 : #define MAX_BPF_STACK 512
84 :
85 : /* Helper macros for filter block array initializers. */
86 :
87 : /* ALU ops on registers, bpf_add|sub|...: dst_reg += src_reg */
88 :
89 : #define BPF_ALU64_REG(OP, DST, SRC) \
90 : ((struct bpf_insn) { \
91 : .code = BPF_ALU64 | BPF_OP(OP) | BPF_X, \
92 : .dst_reg = DST, \
93 : .src_reg = SRC, \
94 : .off = 0, \
95 : .imm = 0 })
96 :
97 : #define BPF_ALU32_REG(OP, DST, SRC) \
98 : ((struct bpf_insn) { \
99 : .code = BPF_ALU | BPF_OP(OP) | BPF_X, \
100 : .dst_reg = DST, \
101 : .src_reg = SRC, \
102 : .off = 0, \
103 : .imm = 0 })
104 :
105 : /* ALU ops on immediates, bpf_add|sub|...: dst_reg += imm32 */
106 :
107 : #define BPF_ALU64_IMM(OP, DST, IMM) \
108 : ((struct bpf_insn) { \
109 : .code = BPF_ALU64 | BPF_OP(OP) | BPF_K, \
110 : .dst_reg = DST, \
111 : .src_reg = 0, \
112 : .off = 0, \
113 : .imm = IMM })
114 :
115 : #define BPF_ALU32_IMM(OP, DST, IMM) \
116 : ((struct bpf_insn) { \
117 : .code = BPF_ALU | BPF_OP(OP) | BPF_K, \
118 : .dst_reg = DST, \
119 : .src_reg = 0, \
120 : .off = 0, \
121 : .imm = IMM })
122 :
123 : /* Endianess conversion, cpu_to_{l,b}e(), {l,b}e_to_cpu() */
124 :
125 : #define BPF_ENDIAN(TYPE, DST, LEN) \
126 : ((struct bpf_insn) { \
127 : .code = BPF_ALU | BPF_END | BPF_SRC(TYPE), \
128 : .dst_reg = DST, \
129 : .src_reg = 0, \
130 : .off = 0, \
131 : .imm = LEN })
132 :
133 : /* Short form of mov, dst_reg = src_reg */
134 :
135 : #define BPF_MOV64_REG(DST, SRC) \
136 : ((struct bpf_insn) { \
137 : .code = BPF_ALU64 | BPF_MOV | BPF_X, \
138 : .dst_reg = DST, \
139 : .src_reg = SRC, \
140 : .off = 0, \
141 : .imm = 0 })
142 :
143 : #define BPF_MOV32_REG(DST, SRC) \
144 : ((struct bpf_insn) { \
145 : .code = BPF_ALU | BPF_MOV | BPF_X, \
146 : .dst_reg = DST, \
147 : .src_reg = SRC, \
148 : .off = 0, \
149 : .imm = 0 })
150 :
151 : /* Short form of mov, dst_reg = imm32 */
152 :
153 : #define BPF_MOV64_IMM(DST, IMM) \
154 : ((struct bpf_insn) { \
155 : .code = BPF_ALU64 | BPF_MOV | BPF_K, \
156 : .dst_reg = DST, \
157 : .src_reg = 0, \
158 : .off = 0, \
159 : .imm = IMM })
160 :
161 : #define BPF_MOV32_IMM(DST, IMM) \
162 : ((struct bpf_insn) { \
163 : .code = BPF_ALU | BPF_MOV | BPF_K, \
164 : .dst_reg = DST, \
165 : .src_reg = 0, \
166 : .off = 0, \
167 : .imm = IMM })
168 :
169 : /* Special form of mov32, used for doing explicit zero extension on dst. */
170 : #define BPF_ZEXT_REG(DST) \
171 : ((struct bpf_insn) { \
172 : .code = BPF_ALU | BPF_MOV | BPF_X, \
173 : .dst_reg = DST, \
174 : .src_reg = DST, \
175 : .off = 0, \
176 : .imm = 1 })
177 :
178 : static inline bool insn_is_zext(const struct bpf_insn *insn)
179 : {
180 : return insn->code == (BPF_ALU | BPF_MOV | BPF_X) && insn->imm == 1;
181 : }
182 :
183 : /* BPF_LD_IMM64 macro encodes single 'load 64-bit immediate' insn */
184 : #define BPF_LD_IMM64(DST, IMM) \
185 : BPF_LD_IMM64_RAW(DST, 0, IMM)
186 :
187 : #define BPF_LD_IMM64_RAW(DST, SRC, IMM) \
188 : ((struct bpf_insn) { \
189 : .code = BPF_LD | BPF_DW | BPF_IMM, \
190 : .dst_reg = DST, \
191 : .src_reg = SRC, \
192 : .off = 0, \
193 : .imm = (__u32) (IMM) }), \
194 : ((struct bpf_insn) { \
195 : .code = 0, /* zero is reserved opcode */ \
196 : .dst_reg = 0, \
197 : .src_reg = 0, \
198 : .off = 0, \
199 : .imm = ((__u64) (IMM)) >> 32 })
200 :
201 : /* pseudo BPF_LD_IMM64 insn used to refer to process-local map_fd */
202 : #define BPF_LD_MAP_FD(DST, MAP_FD) \
203 : BPF_LD_IMM64_RAW(DST, BPF_PSEUDO_MAP_FD, MAP_FD)
204 :
205 : /* Short form of mov based on type, BPF_X: dst_reg = src_reg, BPF_K: dst_reg = imm32 */
206 :
207 : #define BPF_MOV64_RAW(TYPE, DST, SRC, IMM) \
208 : ((struct bpf_insn) { \
209 : .code = BPF_ALU64 | BPF_MOV | BPF_SRC(TYPE), \
210 : .dst_reg = DST, \
211 : .src_reg = SRC, \
212 : .off = 0, \
213 : .imm = IMM })
214 :
215 : #define BPF_MOV32_RAW(TYPE, DST, SRC, IMM) \
216 : ((struct bpf_insn) { \
217 : .code = BPF_ALU | BPF_MOV | BPF_SRC(TYPE), \
218 : .dst_reg = DST, \
219 : .src_reg = SRC, \
220 : .off = 0, \
221 : .imm = IMM })
222 :
223 : /* Direct packet access, R0 = *(uint *) (skb->data + imm32) */
224 :
225 : #define BPF_LD_ABS(SIZE, IMM) \
226 : ((struct bpf_insn) { \
227 : .code = BPF_LD | BPF_SIZE(SIZE) | BPF_ABS, \
228 : .dst_reg = 0, \
229 : .src_reg = 0, \
230 : .off = 0, \
231 : .imm = IMM })
232 :
233 : /* Indirect packet access, R0 = *(uint *) (skb->data + src_reg + imm32) */
234 :
235 : #define BPF_LD_IND(SIZE, SRC, IMM) \
236 : ((struct bpf_insn) { \
237 : .code = BPF_LD | BPF_SIZE(SIZE) | BPF_IND, \
238 : .dst_reg = 0, \
239 : .src_reg = SRC, \
240 : .off = 0, \
241 : .imm = IMM })
242 :
243 : /* Memory load, dst_reg = *(uint *) (src_reg + off16) */
244 :
245 : #define BPF_LDX_MEM(SIZE, DST, SRC, OFF) \
246 : ((struct bpf_insn) { \
247 : .code = BPF_LDX | BPF_SIZE(SIZE) | BPF_MEM, \
248 : .dst_reg = DST, \
249 : .src_reg = SRC, \
250 : .off = OFF, \
251 : .imm = 0 })
252 :
253 : /* Memory store, *(uint *) (dst_reg + off16) = src_reg */
254 :
255 : #define BPF_STX_MEM(SIZE, DST, SRC, OFF) \
256 : ((struct bpf_insn) { \
257 : .code = BPF_STX | BPF_SIZE(SIZE) | BPF_MEM, \
258 : .dst_reg = DST, \
259 : .src_reg = SRC, \
260 : .off = OFF, \
261 : .imm = 0 })
262 :
263 :
264 : /*
265 : * Atomic operations:
266 : *
267 : * BPF_ADD *(uint *) (dst_reg + off16) += src_reg
268 : * BPF_AND *(uint *) (dst_reg + off16) &= src_reg
269 : * BPF_OR *(uint *) (dst_reg + off16) |= src_reg
270 : * BPF_XOR *(uint *) (dst_reg + off16) ^= src_reg
271 : * BPF_ADD | BPF_FETCH src_reg = atomic_fetch_add(dst_reg + off16, src_reg);
272 : * BPF_AND | BPF_FETCH src_reg = atomic_fetch_and(dst_reg + off16, src_reg);
273 : * BPF_OR | BPF_FETCH src_reg = atomic_fetch_or(dst_reg + off16, src_reg);
274 : * BPF_XOR | BPF_FETCH src_reg = atomic_fetch_xor(dst_reg + off16, src_reg);
275 : * BPF_XCHG src_reg = atomic_xchg(dst_reg + off16, src_reg)
276 : * BPF_CMPXCHG r0 = atomic_cmpxchg(dst_reg + off16, r0, src_reg)
277 : */
278 :
279 : #define BPF_ATOMIC_OP(SIZE, OP, DST, SRC, OFF) \
280 : ((struct bpf_insn) { \
281 : .code = BPF_STX | BPF_SIZE(SIZE) | BPF_ATOMIC, \
282 : .dst_reg = DST, \
283 : .src_reg = SRC, \
284 : .off = OFF, \
285 : .imm = OP })
286 :
287 : /* Legacy alias */
288 : #define BPF_STX_XADD(SIZE, DST, SRC, OFF) BPF_ATOMIC_OP(SIZE, BPF_ADD, DST, SRC, OFF)
289 :
290 : /* Memory store, *(uint *) (dst_reg + off16) = imm32 */
291 :
292 : #define BPF_ST_MEM(SIZE, DST, OFF, IMM) \
293 : ((struct bpf_insn) { \
294 : .code = BPF_ST | BPF_SIZE(SIZE) | BPF_MEM, \
295 : .dst_reg = DST, \
296 : .src_reg = 0, \
297 : .off = OFF, \
298 : .imm = IMM })
299 :
300 : /* Conditional jumps against registers, if (dst_reg 'op' src_reg) goto pc + off16 */
301 :
302 : #define BPF_JMP_REG(OP, DST, SRC, OFF) \
303 : ((struct bpf_insn) { \
304 : .code = BPF_JMP | BPF_OP(OP) | BPF_X, \
305 : .dst_reg = DST, \
306 : .src_reg = SRC, \
307 : .off = OFF, \
308 : .imm = 0 })
309 :
310 : /* Conditional jumps against immediates, if (dst_reg 'op' imm32) goto pc + off16 */
311 :
312 : #define BPF_JMP_IMM(OP, DST, IMM, OFF) \
313 : ((struct bpf_insn) { \
314 : .code = BPF_JMP | BPF_OP(OP) | BPF_K, \
315 : .dst_reg = DST, \
316 : .src_reg = 0, \
317 : .off = OFF, \
318 : .imm = IMM })
319 :
320 : /* Like BPF_JMP_REG, but with 32-bit wide operands for comparison. */
321 :
322 : #define BPF_JMP32_REG(OP, DST, SRC, OFF) \
323 : ((struct bpf_insn) { \
324 : .code = BPF_JMP32 | BPF_OP(OP) | BPF_X, \
325 : .dst_reg = DST, \
326 : .src_reg = SRC, \
327 : .off = OFF, \
328 : .imm = 0 })
329 :
330 : /* Like BPF_JMP_IMM, but with 32-bit wide operands for comparison. */
331 :
332 : #define BPF_JMP32_IMM(OP, DST, IMM, OFF) \
333 : ((struct bpf_insn) { \
334 : .code = BPF_JMP32 | BPF_OP(OP) | BPF_K, \
335 : .dst_reg = DST, \
336 : .src_reg = 0, \
337 : .off = OFF, \
338 : .imm = IMM })
339 :
340 : /* Unconditional jumps, goto pc + off16 */
341 :
342 : #define BPF_JMP_A(OFF) \
343 : ((struct bpf_insn) { \
344 : .code = BPF_JMP | BPF_JA, \
345 : .dst_reg = 0, \
346 : .src_reg = 0, \
347 : .off = OFF, \
348 : .imm = 0 })
349 :
350 : /* Relative call */
351 :
352 : #define BPF_CALL_REL(TGT) \
353 : ((struct bpf_insn) { \
354 : .code = BPF_JMP | BPF_CALL, \
355 : .dst_reg = 0, \
356 : .src_reg = BPF_PSEUDO_CALL, \
357 : .off = 0, \
358 : .imm = TGT })
359 :
360 : /* Function call */
361 :
362 : #define BPF_CAST_CALL(x) \
363 : ((u64 (*)(u64, u64, u64, u64, u64))(x))
364 :
365 : #define BPF_EMIT_CALL(FUNC) \
366 : ((struct bpf_insn) { \
367 : .code = BPF_JMP | BPF_CALL, \
368 : .dst_reg = 0, \
369 : .src_reg = 0, \
370 : .off = 0, \
371 : .imm = ((FUNC) - __bpf_call_base) })
372 :
373 : /* Raw code statement block */
374 :
375 : #define BPF_RAW_INSN(CODE, DST, SRC, OFF, IMM) \
376 : ((struct bpf_insn) { \
377 : .code = CODE, \
378 : .dst_reg = DST, \
379 : .src_reg = SRC, \
380 : .off = OFF, \
381 : .imm = IMM })
382 :
383 : /* Program exit */
384 :
385 : #define BPF_EXIT_INSN() \
386 : ((struct bpf_insn) { \
387 : .code = BPF_JMP | BPF_EXIT, \
388 : .dst_reg = 0, \
389 : .src_reg = 0, \
390 : .off = 0, \
391 : .imm = 0 })
392 :
393 : /* Internal classic blocks for direct assignment */
394 :
395 : #define __BPF_STMT(CODE, K) \
396 : ((struct sock_filter) BPF_STMT(CODE, K))
397 :
398 : #define __BPF_JUMP(CODE, K, JT, JF) \
399 : ((struct sock_filter) BPF_JUMP(CODE, K, JT, JF))
400 :
401 : #define bytes_to_bpf_size(bytes) \
402 : ({ \
403 : int bpf_size = -EINVAL; \
404 : \
405 : if (bytes == sizeof(u8)) \
406 : bpf_size = BPF_B; \
407 : else if (bytes == sizeof(u16)) \
408 : bpf_size = BPF_H; \
409 : else if (bytes == sizeof(u32)) \
410 : bpf_size = BPF_W; \
411 : else if (bytes == sizeof(u64)) \
412 : bpf_size = BPF_DW; \
413 : \
414 : bpf_size; \
415 : })
416 :
417 : #define bpf_size_to_bytes(bpf_size) \
418 : ({ \
419 : int bytes = -EINVAL; \
420 : \
421 : if (bpf_size == BPF_B) \
422 : bytes = sizeof(u8); \
423 : else if (bpf_size == BPF_H) \
424 : bytes = sizeof(u16); \
425 : else if (bpf_size == BPF_W) \
426 : bytes = sizeof(u32); \
427 : else if (bpf_size == BPF_DW) \
428 : bytes = sizeof(u64); \
429 : \
430 : bytes; \
431 : })
432 :
433 : #define BPF_SIZEOF(type) \
434 : ({ \
435 : const int __size = bytes_to_bpf_size(sizeof(type)); \
436 : BUILD_BUG_ON(__size < 0); \
437 : __size; \
438 : })
439 :
440 : #define BPF_FIELD_SIZEOF(type, field) \
441 : ({ \
442 : const int __size = bytes_to_bpf_size(sizeof_field(type, field)); \
443 : BUILD_BUG_ON(__size < 0); \
444 : __size; \
445 : })
446 :
447 : #define BPF_LDST_BYTES(insn) \
448 : ({ \
449 : const int __size = bpf_size_to_bytes(BPF_SIZE((insn)->code)); \
450 : WARN_ON(__size < 0); \
451 : __size; \
452 : })
453 :
454 : #define __BPF_MAP_0(m, v, ...) v
455 : #define __BPF_MAP_1(m, v, t, a, ...) m(t, a)
456 : #define __BPF_MAP_2(m, v, t, a, ...) m(t, a), __BPF_MAP_1(m, v, __VA_ARGS__)
457 : #define __BPF_MAP_3(m, v, t, a, ...) m(t, a), __BPF_MAP_2(m, v, __VA_ARGS__)
458 : #define __BPF_MAP_4(m, v, t, a, ...) m(t, a), __BPF_MAP_3(m, v, __VA_ARGS__)
459 : #define __BPF_MAP_5(m, v, t, a, ...) m(t, a), __BPF_MAP_4(m, v, __VA_ARGS__)
460 :
461 : #define __BPF_REG_0(...) __BPF_PAD(5)
462 : #define __BPF_REG_1(...) __BPF_MAP(1, __VA_ARGS__), __BPF_PAD(4)
463 : #define __BPF_REG_2(...) __BPF_MAP(2, __VA_ARGS__), __BPF_PAD(3)
464 : #define __BPF_REG_3(...) __BPF_MAP(3, __VA_ARGS__), __BPF_PAD(2)
465 : #define __BPF_REG_4(...) __BPF_MAP(4, __VA_ARGS__), __BPF_PAD(1)
466 : #define __BPF_REG_5(...) __BPF_MAP(5, __VA_ARGS__)
467 :
468 : #define __BPF_MAP(n, ...) __BPF_MAP_##n(__VA_ARGS__)
469 : #define __BPF_REG(n, ...) __BPF_REG_##n(__VA_ARGS__)
470 :
471 : #define __BPF_CAST(t, a) \
472 : (__force t) \
473 : (__force \
474 : typeof(__builtin_choose_expr(sizeof(t) == sizeof(unsigned long), \
475 : (unsigned long)0, (t)0))) a
476 : #define __BPF_V void
477 : #define __BPF_N
478 :
479 : #define __BPF_DECL_ARGS(t, a) t a
480 : #define __BPF_DECL_REGS(t, a) u64 a
481 :
482 : #define __BPF_PAD(n) \
483 : __BPF_MAP(n, __BPF_DECL_ARGS, __BPF_N, u64, __ur_1, u64, __ur_2, \
484 : u64, __ur_3, u64, __ur_4, u64, __ur_5)
485 :
486 : #define BPF_CALL_x(x, name, ...) \
487 : static __always_inline \
488 : u64 ____##name(__BPF_MAP(x, __BPF_DECL_ARGS, __BPF_V, __VA_ARGS__)); \
489 : typedef u64 (*btf_##name)(__BPF_MAP(x, __BPF_DECL_ARGS, __BPF_V, __VA_ARGS__)); \
490 : u64 name(__BPF_REG(x, __BPF_DECL_REGS, __BPF_N, __VA_ARGS__)); \
491 : u64 name(__BPF_REG(x, __BPF_DECL_REGS, __BPF_N, __VA_ARGS__)) \
492 : { \
493 : return ((btf_##name)____##name)(__BPF_MAP(x,__BPF_CAST,__BPF_N,__VA_ARGS__));\
494 : } \
495 : static __always_inline \
496 : u64 ____##name(__BPF_MAP(x, __BPF_DECL_ARGS, __BPF_V, __VA_ARGS__))
497 :
498 : #define BPF_CALL_0(name, ...) BPF_CALL_x(0, name, __VA_ARGS__)
499 : #define BPF_CALL_1(name, ...) BPF_CALL_x(1, name, __VA_ARGS__)
500 : #define BPF_CALL_2(name, ...) BPF_CALL_x(2, name, __VA_ARGS__)
501 : #define BPF_CALL_3(name, ...) BPF_CALL_x(3, name, __VA_ARGS__)
502 : #define BPF_CALL_4(name, ...) BPF_CALL_x(4, name, __VA_ARGS__)
503 : #define BPF_CALL_5(name, ...) BPF_CALL_x(5, name, __VA_ARGS__)
504 :
505 : #define bpf_ctx_range(TYPE, MEMBER) \
506 : offsetof(TYPE, MEMBER) ... offsetofend(TYPE, MEMBER) - 1
507 : #define bpf_ctx_range_till(TYPE, MEMBER1, MEMBER2) \
508 : offsetof(TYPE, MEMBER1) ... offsetofend(TYPE, MEMBER2) - 1
509 : #if BITS_PER_LONG == 64
510 : # define bpf_ctx_range_ptr(TYPE, MEMBER) \
511 : offsetof(TYPE, MEMBER) ... offsetofend(TYPE, MEMBER) - 1
512 : #else
513 : # define bpf_ctx_range_ptr(TYPE, MEMBER) \
514 : offsetof(TYPE, MEMBER) ... offsetof(TYPE, MEMBER) + 8 - 1
515 : #endif /* BITS_PER_LONG == 64 */
516 :
517 : #define bpf_target_off(TYPE, MEMBER, SIZE, PTR_SIZE) \
518 : ({ \
519 : BUILD_BUG_ON(sizeof_field(TYPE, MEMBER) != (SIZE)); \
520 : *(PTR_SIZE) = (SIZE); \
521 : offsetof(TYPE, MEMBER); \
522 : })
523 :
524 : /* A struct sock_filter is architecture independent. */
525 : struct compat_sock_fprog {
526 : u16 len;
527 : compat_uptr_t filter; /* struct sock_filter * */
528 : };
529 :
530 : struct sock_fprog_kern {
531 : u16 len;
532 : struct sock_filter *filter;
533 : };
534 :
535 : /* Some arches need doubleword alignment for their instructions and/or data */
536 : #define BPF_IMAGE_ALIGNMENT 8
537 :
538 : struct bpf_binary_header {
539 : u32 pages;
540 : u8 image[] __aligned(BPF_IMAGE_ALIGNMENT);
541 : };
542 :
543 : struct bpf_prog_stats {
544 : u64 cnt;
545 : u64 nsecs;
546 : u64 misses;
547 : struct u64_stats_sync syncp;
548 : } __aligned(2 * sizeof(u64));
549 :
550 : struct bpf_prog {
551 : u16 pages; /* Number of allocated pages */
552 : u16 jited:1, /* Is our filter JIT'ed? */
553 : jit_requested:1,/* archs need to JIT the prog */
554 : gpl_compatible:1, /* Is filter GPL compatible? */
555 : cb_access:1, /* Is control block accessed? */
556 : dst_needed:1, /* Do we need dst entry? */
557 : blinded:1, /* Was blinded */
558 : is_func:1, /* program is a bpf function */
559 : kprobe_override:1, /* Do we override a kprobe? */
560 : has_callchain_buf:1, /* callchain buffer allocated? */
561 : enforce_expected_attach_type:1, /* Enforce expected_attach_type checking at attach time */
562 : call_get_stack:1; /* Do we call bpf_get_stack() or bpf_get_stackid() */
563 : enum bpf_prog_type type; /* Type of BPF program */
564 : enum bpf_attach_type expected_attach_type; /* For some prog types */
565 : u32 len; /* Number of filter blocks */
566 : u32 jited_len; /* Size of jited insns in bytes */
567 : u8 tag[BPF_TAG_SIZE];
568 : struct bpf_prog_stats __percpu *stats;
569 : int __percpu *active;
570 : unsigned int (*bpf_func)(const void *ctx,
571 : const struct bpf_insn *insn);
572 : struct bpf_prog_aux *aux; /* Auxiliary fields */
573 : struct sock_fprog_kern *orig_prog; /* Original BPF program */
574 : /* Instructions for interpreter */
575 : struct sock_filter insns[0];
576 : struct bpf_insn insnsi[];
577 : };
578 :
579 : struct sk_filter {
580 : refcount_t refcnt;
581 : struct rcu_head rcu;
582 : struct bpf_prog *prog;
583 : };
584 :
585 : DECLARE_STATIC_KEY_FALSE(bpf_stats_enabled_key);
586 :
587 : #define __BPF_PROG_RUN(prog, ctx, dfunc) ({ \
588 : u32 __ret; \
589 : cant_migrate(); \
590 : if (static_branch_unlikely(&bpf_stats_enabled_key)) { \
591 : struct bpf_prog_stats *__stats; \
592 : u64 __start = sched_clock(); \
593 : __ret = dfunc(ctx, (prog)->insnsi, (prog)->bpf_func); \
594 : __stats = this_cpu_ptr(prog->stats); \
595 : u64_stats_update_begin(&__stats->syncp); \
596 : __stats->cnt++; \
597 : __stats->nsecs += sched_clock() - __start; \
598 : u64_stats_update_end(&__stats->syncp); \
599 : } else { \
600 : __ret = dfunc(ctx, (prog)->insnsi, (prog)->bpf_func); \
601 : } \
602 : __ret; })
603 :
604 : #define BPF_PROG_RUN(prog, ctx) \
605 : __BPF_PROG_RUN(prog, ctx, bpf_dispatcher_nop_func)
606 :
607 : /*
608 : * Use in preemptible and therefore migratable context to make sure that
609 : * the execution of the BPF program runs on one CPU.
610 : *
611 : * This uses migrate_disable/enable() explicitly to document that the
612 : * invocation of a BPF program does not require reentrancy protection
613 : * against a BPF program which is invoked from a preempting task.
614 : *
615 : * For non RT enabled kernels migrate_disable/enable() maps to
616 : * preempt_disable/enable(), i.e. it disables also preemption.
617 : */
618 908 : static inline u32 bpf_prog_run_pin_on_cpu(const struct bpf_prog *prog,
619 : const void *ctx)
620 : {
621 908 : u32 ret;
622 :
623 908 : migrate_disable();
624 908 : ret = __BPF_PROG_RUN(prog, ctx, bpf_dispatcher_nop_func);
625 908 : migrate_enable();
626 908 : return ret;
627 : }
628 :
629 : #define BPF_SKB_CB_LEN QDISC_CB_PRIV_LEN
630 :
631 : struct bpf_skb_data_end {
632 : struct qdisc_skb_cb qdisc_cb;
633 : void *data_meta;
634 : void *data_end;
635 : };
636 :
637 : struct bpf_nh_params {
638 : u32 nh_family;
639 : union {
640 : u32 ipv4_nh;
641 : struct in6_addr ipv6_nh;
642 : };
643 : };
644 :
645 : struct bpf_redirect_info {
646 : u32 flags;
647 : u32 tgt_index;
648 : void *tgt_value;
649 : struct bpf_map *map;
650 : u32 kern_flags;
651 : struct bpf_nh_params nh;
652 : };
653 :
654 : DECLARE_PER_CPU(struct bpf_redirect_info, bpf_redirect_info);
655 :
656 : /* flags for bpf_redirect_info kern_flags */
657 : #define BPF_RI_F_RF_NO_DIRECT BIT(0) /* no napi_direct on return_frame */
658 :
659 : /* Compute the linear packet data range [data, data_end) which
660 : * will be accessed by various program types (cls_bpf, act_bpf,
661 : * lwt, ...). Subsystems allowing direct data access must (!)
662 : * ensure that cb[] area can be written to when BPF program is
663 : * invoked (otherwise cb[] save/restore is necessary).
664 : */
665 0 : static inline void bpf_compute_data_pointers(struct sk_buff *skb)
666 : {
667 0 : struct bpf_skb_data_end *cb = (struct bpf_skb_data_end *)skb->cb;
668 :
669 0 : BUILD_BUG_ON(sizeof(*cb) > sizeof_field(struct sk_buff, cb));
670 0 : cb->data_meta = skb->data - skb_metadata_len(skb);
671 0 : cb->data_end = skb->data + skb_headlen(skb);
672 0 : }
673 :
674 : /* Similar to bpf_compute_data_pointers(), except that save orginal
675 : * data in cb->data and cb->meta_data for restore.
676 : */
677 : static inline void bpf_compute_and_save_data_end(
678 : struct sk_buff *skb, void **saved_data_end)
679 : {
680 : struct bpf_skb_data_end *cb = (struct bpf_skb_data_end *)skb->cb;
681 :
682 : *saved_data_end = cb->data_end;
683 : cb->data_end = skb->data + skb_headlen(skb);
684 : }
685 :
686 : /* Restore data saved by bpf_compute_data_pointers(). */
687 : static inline void bpf_restore_data_end(
688 : struct sk_buff *skb, void *saved_data_end)
689 : {
690 : struct bpf_skb_data_end *cb = (struct bpf_skb_data_end *)skb->cb;
691 :
692 : cb->data_end = saved_data_end;
693 : }
694 :
695 1094 : static inline u8 *bpf_skb_cb(struct sk_buff *skb)
696 : {
697 : /* eBPF programs may read/write skb->cb[] area to transfer meta
698 : * data between tail calls. Since this also needs to work with
699 : * tc, that scratch memory is mapped to qdisc_skb_cb's data area.
700 : *
701 : * In some socket filter cases, the cb unfortunately needs to be
702 : * saved/restored so that protocol specific skb->cb[] data won't
703 : * be lost. In any case, due to unpriviledged eBPF programs
704 : * attached to sockets, we need to clear the bpf_skb_cb() area
705 : * to not leak previous contents to user space.
706 : */
707 1094 : BUILD_BUG_ON(sizeof_field(struct __sk_buff, cb) != BPF_SKB_CB_LEN);
708 1094 : BUILD_BUG_ON(sizeof_field(struct __sk_buff, cb) !=
709 : sizeof_field(struct qdisc_skb_cb, data));
710 :
711 1094 : return qdisc_skb_cb(skb)->data;
712 : }
713 :
714 : /* Must be invoked with migration disabled */
715 186 : static inline u32 __bpf_prog_run_save_cb(const struct bpf_prog *prog,
716 : struct sk_buff *skb)
717 : {
718 186 : u8 *cb_data = bpf_skb_cb(skb);
719 186 : u8 cb_saved[BPF_SKB_CB_LEN];
720 186 : u32 res;
721 :
722 186 : if (unlikely(prog->cb_access)) {
723 0 : memcpy(cb_saved, cb_data, sizeof(cb_saved));
724 0 : memset(cb_data, 0, sizeof(cb_saved));
725 : }
726 :
727 186 : res = BPF_PROG_RUN(prog, skb);
728 :
729 186 : if (unlikely(prog->cb_access))
730 0 : memcpy(cb_data, cb_saved, sizeof(cb_saved));
731 :
732 186 : return res;
733 : }
734 :
735 186 : static inline u32 bpf_prog_run_save_cb(const struct bpf_prog *prog,
736 : struct sk_buff *skb)
737 : {
738 186 : u32 res;
739 :
740 186 : migrate_disable();
741 186 : res = __bpf_prog_run_save_cb(prog, skb);
742 186 : migrate_enable();
743 186 : return res;
744 : }
745 :
746 908 : static inline u32 bpf_prog_run_clear_cb(const struct bpf_prog *prog,
747 : struct sk_buff *skb)
748 : {
749 908 : u8 *cb_data = bpf_skb_cb(skb);
750 908 : u32 res;
751 :
752 908 : if (unlikely(prog->cb_access))
753 0 : memset(cb_data, 0, BPF_SKB_CB_LEN);
754 :
755 908 : res = bpf_prog_run_pin_on_cpu(prog, skb);
756 908 : return res;
757 : }
758 :
759 : DECLARE_BPF_DISPATCHER(xdp)
760 :
761 0 : static __always_inline u32 bpf_prog_run_xdp(const struct bpf_prog *prog,
762 : struct xdp_buff *xdp)
763 : {
764 : /* Caller needs to hold rcu_read_lock() (!), otherwise program
765 : * can be released while still running, or map elements could be
766 : * freed early while still having concurrent users. XDP fastpath
767 : * already takes rcu_read_lock() when fetching the program, so
768 : * it's not necessary here anymore.
769 : */
770 0 : return __BPF_PROG_RUN(prog, xdp, BPF_DISPATCHER_FUNC(xdp));
771 : }
772 :
773 : void bpf_prog_change_xdp(struct bpf_prog *prev_prog, struct bpf_prog *prog);
774 :
775 0 : static inline u32 bpf_prog_insn_size(const struct bpf_prog *prog)
776 : {
777 0 : return prog->len * sizeof(struct bpf_insn);
778 : }
779 :
780 0 : static inline u32 bpf_prog_tag_scratch_size(const struct bpf_prog *prog)
781 : {
782 0 : return round_up(bpf_prog_insn_size(prog) +
783 : sizeof(__be64) + 1, SHA1_BLOCK_SIZE);
784 : }
785 :
786 21 : static inline unsigned int bpf_prog_size(unsigned int proglen)
787 : {
788 21 : return max(sizeof(struct bpf_prog),
789 : offsetof(struct bpf_prog, insns[proglen]));
790 : }
791 :
792 : static inline bool bpf_prog_was_classic(const struct bpf_prog *prog)
793 : {
794 : /* When classic BPF programs have been loaded and the arch
795 : * does not have a classic BPF JIT (anymore), they have been
796 : * converted via bpf_migrate_filter() to eBPF and thus always
797 : * have an unspec program type.
798 : */
799 : return prog->type == BPF_PROG_TYPE_UNSPEC;
800 : }
801 :
802 : static inline u32 bpf_ctx_off_adjust_machine(u32 size)
803 : {
804 : const u32 size_machine = sizeof(unsigned long);
805 :
806 : if (size > size_machine && size % size_machine == 0)
807 : size = size_machine;
808 :
809 : return size;
810 : }
811 :
812 : static inline bool
813 0 : bpf_ctx_narrow_access_ok(u32 off, u32 size, u32 size_default)
814 : {
815 0 : return size <= size_default && (size & (size - 1)) == 0;
816 : }
817 :
818 : static inline u8
819 : bpf_ctx_narrow_access_offset(u32 off, u32 size, u32 size_default)
820 : {
821 : u8 access_off = off & (size_default - 1);
822 :
823 : #ifdef __LITTLE_ENDIAN
824 : return access_off;
825 : #else
826 : return size_default - (access_off + size);
827 : #endif
828 : }
829 :
830 : #define bpf_ctx_wide_access_ok(off, size, type, field) \
831 : (size == sizeof(__u64) && \
832 : off >= offsetof(type, field) && \
833 : off + sizeof(__u64) <= offsetofend(type, field) && \
834 : off % sizeof(__u64) == 0)
835 :
836 : #define bpf_classic_proglen(fprog) (fprog->len * sizeof(fprog->filter[0]))
837 :
838 7 : static inline void bpf_prog_lock_ro(struct bpf_prog *fp)
839 : {
840 : #ifndef CONFIG_BPF_JIT_ALWAYS_ON
841 7 : if (!fp->jited) {
842 7 : set_vm_flush_reset_perms(fp);
843 7 : set_memory_ro((unsigned long)fp, fp->pages);
844 : }
845 : #endif
846 7 : }
847 :
848 : static inline void bpf_jit_binary_lock_ro(struct bpf_binary_header *hdr)
849 : {
850 : set_vm_flush_reset_perms(hdr);
851 : set_memory_ro((unsigned long)hdr, hdr->pages);
852 : set_memory_x((unsigned long)hdr, hdr->pages);
853 : }
854 :
855 : static inline struct bpf_binary_header *
856 : bpf_jit_binary_hdr(const struct bpf_prog *fp)
857 : {
858 : unsigned long real_start = (unsigned long)fp->bpf_func;
859 : unsigned long addr = real_start & PAGE_MASK;
860 :
861 : return (void *)addr;
862 : }
863 :
864 : int sk_filter_trim_cap(struct sock *sk, struct sk_buff *skb, unsigned int cap);
865 1442 : static inline int sk_filter(struct sock *sk, struct sk_buff *skb)
866 : {
867 1442 : return sk_filter_trim_cap(sk, skb, 1);
868 : }
869 :
870 : struct bpf_prog *bpf_prog_select_runtime(struct bpf_prog *fp, int *err);
871 : void bpf_prog_free(struct bpf_prog *fp);
872 :
873 : bool bpf_opcode_in_insntable(u8 code);
874 :
875 : void bpf_prog_free_linfo(struct bpf_prog *prog);
876 : void bpf_prog_fill_jited_linfo(struct bpf_prog *prog,
877 : const u32 *insn_to_jit_off);
878 : int bpf_prog_alloc_jited_linfo(struct bpf_prog *prog);
879 : void bpf_prog_free_jited_linfo(struct bpf_prog *prog);
880 : void bpf_prog_free_unused_jited_linfo(struct bpf_prog *prog);
881 :
882 : struct bpf_prog *bpf_prog_alloc(unsigned int size, gfp_t gfp_extra_flags);
883 : struct bpf_prog *bpf_prog_alloc_no_stats(unsigned int size, gfp_t gfp_extra_flags);
884 : struct bpf_prog *bpf_prog_realloc(struct bpf_prog *fp_old, unsigned int size,
885 : gfp_t gfp_extra_flags);
886 : void __bpf_prog_free(struct bpf_prog *fp);
887 :
888 0 : static inline void bpf_prog_unlock_free(struct bpf_prog *fp)
889 : {
890 0 : __bpf_prog_free(fp);
891 0 : }
892 :
893 : typedef int (*bpf_aux_classic_check_t)(struct sock_filter *filter,
894 : unsigned int flen);
895 :
896 : int bpf_prog_create(struct bpf_prog **pfp, struct sock_fprog_kern *fprog);
897 : int bpf_prog_create_from_user(struct bpf_prog **pfp, struct sock_fprog *fprog,
898 : bpf_aux_classic_check_t trans, bool save_orig);
899 : void bpf_prog_destroy(struct bpf_prog *fp);
900 :
901 : int sk_attach_filter(struct sock_fprog *fprog, struct sock *sk);
902 : int sk_attach_bpf(u32 ufd, struct sock *sk);
903 : int sk_reuseport_attach_filter(struct sock_fprog *fprog, struct sock *sk);
904 : int sk_reuseport_attach_bpf(u32 ufd, struct sock *sk);
905 : void sk_reuseport_prog_free(struct bpf_prog *prog);
906 : int sk_detach_filter(struct sock *sk);
907 : int sk_get_filter(struct sock *sk, struct sock_filter __user *filter,
908 : unsigned int len);
909 :
910 : bool sk_filter_charge(struct sock *sk, struct sk_filter *fp);
911 : void sk_filter_uncharge(struct sock *sk, struct sk_filter *fp);
912 :
913 : u64 __bpf_call_base(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5);
914 : #define __bpf_call_base_args \
915 : ((u64 (*)(u64, u64, u64, u64, u64, const struct bpf_insn *)) \
916 : (void *)__bpf_call_base)
917 :
918 : struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog);
919 : void bpf_jit_compile(struct bpf_prog *prog);
920 : bool bpf_jit_needs_zext(void);
921 : bool bpf_helper_changes_pkt_data(void *func);
922 :
923 : static inline bool bpf_dump_raw_ok(const struct cred *cred)
924 : {
925 : /* Reconstruction of call-sites is dependent on kallsyms,
926 : * thus make dump the same restriction.
927 : */
928 : return kallsyms_show_value(cred);
929 : }
930 :
931 : struct bpf_prog *bpf_patch_insn_single(struct bpf_prog *prog, u32 off,
932 : const struct bpf_insn *patch, u32 len);
933 : int bpf_remove_insns(struct bpf_prog *prog, u32 off, u32 cnt);
934 :
935 : void bpf_clear_redirect_map(struct bpf_map *map);
936 :
937 0 : static inline bool xdp_return_frame_no_direct(void)
938 : {
939 0 : struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
940 :
941 0 : return ri->kern_flags & BPF_RI_F_RF_NO_DIRECT;
942 : }
943 :
944 : static inline void xdp_set_return_frame_no_direct(void)
945 : {
946 : struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
947 :
948 : ri->kern_flags |= BPF_RI_F_RF_NO_DIRECT;
949 : }
950 :
951 : static inline void xdp_clear_return_frame_no_direct(void)
952 : {
953 : struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
954 :
955 : ri->kern_flags &= ~BPF_RI_F_RF_NO_DIRECT;
956 : }
957 :
958 0 : static inline int xdp_ok_fwd_dev(const struct net_device *fwd,
959 : unsigned int pktlen)
960 : {
961 0 : unsigned int len;
962 :
963 0 : if (unlikely(!(fwd->flags & IFF_UP)))
964 : return -ENETDOWN;
965 :
966 0 : len = fwd->mtu + fwd->hard_header_len + VLAN_HLEN;
967 0 : if (pktlen > len)
968 0 : return -EMSGSIZE;
969 :
970 : return 0;
971 : }
972 :
973 : /* The pair of xdp_do_redirect and xdp_do_flush MUST be called in the
974 : * same cpu context. Further for best results no more than a single map
975 : * for the do_redirect/do_flush pair should be used. This limitation is
976 : * because we only track one map and force a flush when the map changes.
977 : * This does not appear to be a real limitation for existing software.
978 : */
979 : int xdp_do_generic_redirect(struct net_device *dev, struct sk_buff *skb,
980 : struct xdp_buff *xdp, struct bpf_prog *prog);
981 : int xdp_do_redirect(struct net_device *dev,
982 : struct xdp_buff *xdp,
983 : struct bpf_prog *prog);
984 : void xdp_do_flush(void);
985 :
986 : /* The xdp_do_flush_map() helper has been renamed to drop the _map suffix, as
987 : * it is no longer only flushing maps. Keep this define for compatibility
988 : * until all drivers are updated - do not use xdp_do_flush_map() in new code!
989 : */
990 : #define xdp_do_flush_map xdp_do_flush
991 :
992 : void bpf_warn_invalid_xdp_action(u32 act);
993 :
994 : #ifdef CONFIG_INET
995 : struct sock *bpf_run_sk_reuseport(struct sock_reuseport *reuse, struct sock *sk,
996 : struct bpf_prog *prog, struct sk_buff *skb,
997 : u32 hash);
998 : #else
999 : static inline struct sock *
1000 : bpf_run_sk_reuseport(struct sock_reuseport *reuse, struct sock *sk,
1001 : struct bpf_prog *prog, struct sk_buff *skb,
1002 : u32 hash)
1003 : {
1004 : return NULL;
1005 : }
1006 : #endif
1007 :
1008 : #ifdef CONFIG_BPF_JIT
1009 : extern int bpf_jit_enable;
1010 : extern int bpf_jit_harden;
1011 : extern int bpf_jit_kallsyms;
1012 : extern long bpf_jit_limit;
1013 :
1014 : typedef void (*bpf_jit_fill_hole_t)(void *area, unsigned int size);
1015 :
1016 : struct bpf_binary_header *
1017 : bpf_jit_binary_alloc(unsigned int proglen, u8 **image_ptr,
1018 : unsigned int alignment,
1019 : bpf_jit_fill_hole_t bpf_fill_ill_insns);
1020 : void bpf_jit_binary_free(struct bpf_binary_header *hdr);
1021 : u64 bpf_jit_alloc_exec_limit(void);
1022 : void *bpf_jit_alloc_exec(unsigned long size);
1023 : void bpf_jit_free_exec(void *addr);
1024 : void bpf_jit_free(struct bpf_prog *fp);
1025 :
1026 : int bpf_jit_add_poke_descriptor(struct bpf_prog *prog,
1027 : struct bpf_jit_poke_descriptor *poke);
1028 :
1029 : int bpf_jit_get_func_addr(const struct bpf_prog *prog,
1030 : const struct bpf_insn *insn, bool extra_pass,
1031 : u64 *func_addr, bool *func_addr_fixed);
1032 :
1033 : struct bpf_prog *bpf_jit_blind_constants(struct bpf_prog *fp);
1034 : void bpf_jit_prog_release_other(struct bpf_prog *fp, struct bpf_prog *fp_other);
1035 :
1036 : static inline void bpf_jit_dump(unsigned int flen, unsigned int proglen,
1037 : u32 pass, void *image)
1038 : {
1039 : pr_err("flen=%u proglen=%u pass=%u image=%pK from=%s pid=%d\n", flen,
1040 : proglen, pass, image, current->comm, task_pid_nr(current));
1041 :
1042 : if (image)
1043 : print_hex_dump(KERN_ERR, "JIT code: ", DUMP_PREFIX_OFFSET,
1044 : 16, 1, image, proglen, false);
1045 : }
1046 :
1047 : static inline bool bpf_jit_is_ebpf(void)
1048 : {
1049 : # ifdef CONFIG_HAVE_EBPF_JIT
1050 : return true;
1051 : # else
1052 : return false;
1053 : # endif
1054 : }
1055 :
1056 : static inline bool ebpf_jit_enabled(void)
1057 : {
1058 : return bpf_jit_enable && bpf_jit_is_ebpf();
1059 : }
1060 :
1061 : static inline bool bpf_prog_ebpf_jited(const struct bpf_prog *fp)
1062 : {
1063 : return fp->jited && bpf_jit_is_ebpf();
1064 : }
1065 :
1066 : static inline bool bpf_jit_blinding_enabled(struct bpf_prog *prog)
1067 : {
1068 : /* These are the prerequisites, should someone ever have the
1069 : * idea to call blinding outside of them, we make sure to
1070 : * bail out.
1071 : */
1072 : if (!bpf_jit_is_ebpf())
1073 : return false;
1074 : if (!prog->jit_requested)
1075 : return false;
1076 : if (!bpf_jit_harden)
1077 : return false;
1078 : if (bpf_jit_harden == 1 && capable(CAP_SYS_ADMIN))
1079 : return false;
1080 :
1081 : return true;
1082 : }
1083 :
1084 : static inline bool bpf_jit_kallsyms_enabled(void)
1085 : {
1086 : /* There are a couple of corner cases where kallsyms should
1087 : * not be enabled f.e. on hardening.
1088 : */
1089 : if (bpf_jit_harden)
1090 : return false;
1091 : if (!bpf_jit_kallsyms)
1092 : return false;
1093 : if (bpf_jit_kallsyms == 1)
1094 : return true;
1095 :
1096 : return false;
1097 : }
1098 :
1099 : const char *__bpf_address_lookup(unsigned long addr, unsigned long *size,
1100 : unsigned long *off, char *sym);
1101 : bool is_bpf_text_address(unsigned long addr);
1102 : int bpf_get_kallsym(unsigned int symnum, unsigned long *value, char *type,
1103 : char *sym);
1104 :
1105 : static inline const char *
1106 : bpf_address_lookup(unsigned long addr, unsigned long *size,
1107 : unsigned long *off, char **modname, char *sym)
1108 : {
1109 : const char *ret = __bpf_address_lookup(addr, size, off, sym);
1110 :
1111 : if (ret && modname)
1112 : *modname = NULL;
1113 : return ret;
1114 : }
1115 :
1116 : void bpf_prog_kallsyms_add(struct bpf_prog *fp);
1117 : void bpf_prog_kallsyms_del(struct bpf_prog *fp);
1118 :
1119 : #else /* CONFIG_BPF_JIT */
1120 :
1121 7 : static inline bool ebpf_jit_enabled(void)
1122 : {
1123 7 : return false;
1124 : }
1125 :
1126 : static inline bool bpf_jit_blinding_enabled(struct bpf_prog *prog)
1127 : {
1128 : return false;
1129 : }
1130 :
1131 : static inline bool bpf_prog_ebpf_jited(const struct bpf_prog *fp)
1132 : {
1133 : return false;
1134 : }
1135 :
1136 : static inline int
1137 : bpf_jit_add_poke_descriptor(struct bpf_prog *prog,
1138 : struct bpf_jit_poke_descriptor *poke)
1139 : {
1140 : return -ENOTSUPP;
1141 : }
1142 :
1143 0 : static inline void bpf_jit_free(struct bpf_prog *fp)
1144 : {
1145 0 : bpf_prog_unlock_free(fp);
1146 0 : }
1147 :
1148 : static inline bool bpf_jit_kallsyms_enabled(void)
1149 : {
1150 : return false;
1151 : }
1152 :
1153 : static inline const char *
1154 : __bpf_address_lookup(unsigned long addr, unsigned long *size,
1155 : unsigned long *off, char *sym)
1156 : {
1157 : return NULL;
1158 : }
1159 :
1160 2634183 : static inline bool is_bpf_text_address(unsigned long addr)
1161 : {
1162 2634183 : return false;
1163 : }
1164 :
1165 0 : static inline int bpf_get_kallsym(unsigned int symnum, unsigned long *value,
1166 : char *type, char *sym)
1167 : {
1168 0 : return -ERANGE;
1169 : }
1170 :
1171 : static inline const char *
1172 : bpf_address_lookup(unsigned long addr, unsigned long *size,
1173 : unsigned long *off, char **modname, char *sym)
1174 : {
1175 : return NULL;
1176 : }
1177 :
1178 : static inline void bpf_prog_kallsyms_add(struct bpf_prog *fp)
1179 : {
1180 : }
1181 :
1182 0 : static inline void bpf_prog_kallsyms_del(struct bpf_prog *fp)
1183 : {
1184 0 : }
1185 :
1186 : #endif /* CONFIG_BPF_JIT */
1187 :
1188 : void bpf_prog_kallsyms_del_all(struct bpf_prog *fp);
1189 :
1190 : #define BPF_ANC BIT(15)
1191 :
1192 : static inline bool bpf_needs_clear_a(const struct sock_filter *first)
1193 : {
1194 : switch (first->code) {
1195 : case BPF_RET | BPF_K:
1196 : case BPF_LD | BPF_W | BPF_LEN:
1197 : return false;
1198 :
1199 : case BPF_LD | BPF_W | BPF_ABS:
1200 : case BPF_LD | BPF_H | BPF_ABS:
1201 : case BPF_LD | BPF_B | BPF_ABS:
1202 : if (first->k == SKF_AD_OFF + SKF_AD_ALU_XOR_X)
1203 : return true;
1204 : return false;
1205 :
1206 : default:
1207 : return true;
1208 : }
1209 : }
1210 :
1211 22 : static inline u16 bpf_anc_helper(const struct sock_filter *ftest)
1212 : {
1213 22 : BUG_ON(ftest->code & BPF_ANC);
1214 :
1215 22 : switch (ftest->code) {
1216 22 : case BPF_LD | BPF_W | BPF_ABS:
1217 : case BPF_LD | BPF_H | BPF_ABS:
1218 : case BPF_LD | BPF_B | BPF_ABS:
1219 : #define BPF_ANCILLARY(CODE) case SKF_AD_OFF + SKF_AD_##CODE: \
1220 : return BPF_ANC | SKF_AD_##CODE
1221 22 : switch (ftest->k) {
1222 : BPF_ANCILLARY(PROTOCOL);
1223 0 : BPF_ANCILLARY(PKTTYPE);
1224 0 : BPF_ANCILLARY(IFINDEX);
1225 0 : BPF_ANCILLARY(NLATTR);
1226 0 : BPF_ANCILLARY(NLATTR_NEST);
1227 0 : BPF_ANCILLARY(MARK);
1228 0 : BPF_ANCILLARY(QUEUE);
1229 0 : BPF_ANCILLARY(HATYPE);
1230 0 : BPF_ANCILLARY(RXHASH);
1231 0 : BPF_ANCILLARY(CPU);
1232 0 : BPF_ANCILLARY(ALU_XOR_X);
1233 0 : BPF_ANCILLARY(VLAN_TAG);
1234 0 : BPF_ANCILLARY(VLAN_TAG_PRESENT);
1235 0 : BPF_ANCILLARY(PAY_OFFSET);
1236 0 : BPF_ANCILLARY(RANDOM);
1237 0 : BPF_ANCILLARY(VLAN_TPID);
1238 : }
1239 22 : fallthrough;
1240 : default:
1241 22 : return ftest->code;
1242 : }
1243 : }
1244 :
1245 : void *bpf_internal_load_pointer_neg_helper(const struct sk_buff *skb,
1246 : int k, unsigned int size);
1247 :
1248 : static inline void *bpf_load_pointer(const struct sk_buff *skb, int k,
1249 : unsigned int size, void *buffer)
1250 : {
1251 : if (k >= 0)
1252 : return skb_header_pointer(skb, k, size, buffer);
1253 :
1254 : return bpf_internal_load_pointer_neg_helper(skb, k, size);
1255 : }
1256 :
1257 0 : static inline int bpf_tell_extensions(void)
1258 : {
1259 0 : return SKF_AD_MAX;
1260 : }
1261 :
1262 : struct bpf_sock_addr_kern {
1263 : struct sock *sk;
1264 : struct sockaddr *uaddr;
1265 : /* Temporary "register" to make indirect stores to nested structures
1266 : * defined above. We need three registers to make such a store, but
1267 : * only two (src and dst) are available at convert_ctx_access time
1268 : */
1269 : u64 tmp_reg;
1270 : void *t_ctx; /* Attach type specific context. */
1271 : };
1272 :
1273 : struct bpf_sock_ops_kern {
1274 : struct sock *sk;
1275 : union {
1276 : u32 args[4];
1277 : u32 reply;
1278 : u32 replylong[4];
1279 : };
1280 : struct sk_buff *syn_skb;
1281 : struct sk_buff *skb;
1282 : void *skb_data_end;
1283 : u8 op;
1284 : u8 is_fullsock;
1285 : u8 remaining_opt_len;
1286 : u64 temp; /* temp and everything after is not
1287 : * initialized to 0 before calling
1288 : * the BPF program. New fields that
1289 : * should be initialized to 0 should
1290 : * be inserted before temp.
1291 : * temp is scratch storage used by
1292 : * sock_ops_convert_ctx_access
1293 : * as temporary storage of a register.
1294 : */
1295 : };
1296 :
1297 : struct bpf_sysctl_kern {
1298 : struct ctl_table_header *head;
1299 : struct ctl_table *table;
1300 : void *cur_val;
1301 : size_t cur_len;
1302 : void *new_val;
1303 : size_t new_len;
1304 : int new_updated;
1305 : int write;
1306 : loff_t *ppos;
1307 : /* Temporary "register" for indirect stores to ppos. */
1308 : u64 tmp_reg;
1309 : };
1310 :
1311 : #define BPF_SOCKOPT_KERN_BUF_SIZE 32
1312 : struct bpf_sockopt_buf {
1313 : u8 data[BPF_SOCKOPT_KERN_BUF_SIZE];
1314 : };
1315 :
1316 : struct bpf_sockopt_kern {
1317 : struct sock *sk;
1318 : u8 *optval;
1319 : u8 *optval_end;
1320 : s32 level;
1321 : s32 optname;
1322 : s32 optlen;
1323 : s32 retval;
1324 : };
1325 :
1326 : int copy_bpf_fprog_from_user(struct sock_fprog *dst, sockptr_t src, int len);
1327 :
1328 : struct bpf_sk_lookup_kern {
1329 : u16 family;
1330 : u16 protocol;
1331 : __be16 sport;
1332 : u16 dport;
1333 : struct {
1334 : __be32 saddr;
1335 : __be32 daddr;
1336 : } v4;
1337 : struct {
1338 : const struct in6_addr *saddr;
1339 : const struct in6_addr *daddr;
1340 : } v6;
1341 : struct sock *selected_sk;
1342 : bool no_reuseport;
1343 : };
1344 :
1345 : extern struct static_key_false bpf_sk_lookup_enabled;
1346 :
1347 : /* Runners for BPF_SK_LOOKUP programs to invoke on socket lookup.
1348 : *
1349 : * Allowed return values for a BPF SK_LOOKUP program are SK_PASS and
1350 : * SK_DROP. Their meaning is as follows:
1351 : *
1352 : * SK_PASS && ctx.selected_sk != NULL: use selected_sk as lookup result
1353 : * SK_PASS && ctx.selected_sk == NULL: continue to htable-based socket lookup
1354 : * SK_DROP : terminate lookup with -ECONNREFUSED
1355 : *
1356 : * This macro aggregates return values and selected sockets from
1357 : * multiple BPF programs according to following rules in order:
1358 : *
1359 : * 1. If any program returned SK_PASS and a non-NULL ctx.selected_sk,
1360 : * macro result is SK_PASS and last ctx.selected_sk is used.
1361 : * 2. If any program returned SK_DROP return value,
1362 : * macro result is SK_DROP.
1363 : * 3. Otherwise result is SK_PASS and ctx.selected_sk is NULL.
1364 : *
1365 : * Caller must ensure that the prog array is non-NULL, and that the
1366 : * array as well as the programs it contains remain valid.
1367 : */
1368 : #define BPF_PROG_SK_LOOKUP_RUN_ARRAY(array, ctx, func) \
1369 : ({ \
1370 : struct bpf_sk_lookup_kern *_ctx = &(ctx); \
1371 : struct bpf_prog_array_item *_item; \
1372 : struct sock *_selected_sk = NULL; \
1373 : bool _no_reuseport = false; \
1374 : struct bpf_prog *_prog; \
1375 : bool _all_pass = true; \
1376 : u32 _ret; \
1377 : \
1378 : migrate_disable(); \
1379 : _item = &(array)->items[0]; \
1380 : while ((_prog = READ_ONCE(_item->prog))) { \
1381 : /* restore most recent selection */ \
1382 : _ctx->selected_sk = _selected_sk; \
1383 : _ctx->no_reuseport = _no_reuseport; \
1384 : \
1385 : _ret = func(_prog, _ctx); \
1386 : if (_ret == SK_PASS && _ctx->selected_sk) { \
1387 : /* remember last non-NULL socket */ \
1388 : _selected_sk = _ctx->selected_sk; \
1389 : _no_reuseport = _ctx->no_reuseport; \
1390 : } else if (_ret == SK_DROP && _all_pass) { \
1391 : _all_pass = false; \
1392 : } \
1393 : _item++; \
1394 : } \
1395 : _ctx->selected_sk = _selected_sk; \
1396 : _ctx->no_reuseport = _no_reuseport; \
1397 : migrate_enable(); \
1398 : _all_pass || _selected_sk ? SK_PASS : SK_DROP; \
1399 : })
1400 :
1401 0 : static inline bool bpf_sk_lookup_run_v4(struct net *net, int protocol,
1402 : const __be32 saddr, const __be16 sport,
1403 : const __be32 daddr, const u16 dport,
1404 : struct sock **psk)
1405 : {
1406 0 : struct bpf_prog_array *run_array;
1407 0 : struct sock *selected_sk = NULL;
1408 0 : bool no_reuseport = false;
1409 :
1410 0 : rcu_read_lock();
1411 0 : run_array = rcu_dereference(net->bpf.run_array[NETNS_BPF_SK_LOOKUP]);
1412 0 : if (run_array) {
1413 0 : struct bpf_sk_lookup_kern ctx = {
1414 : .family = AF_INET,
1415 : .protocol = protocol,
1416 : .v4.saddr = saddr,
1417 : .v4.daddr = daddr,
1418 : .sport = sport,
1419 : .dport = dport,
1420 : };
1421 0 : u32 act;
1422 :
1423 0 : act = BPF_PROG_SK_LOOKUP_RUN_ARRAY(run_array, ctx, BPF_PROG_RUN);
1424 0 : if (act == SK_PASS) {
1425 0 : selected_sk = ctx.selected_sk;
1426 0 : no_reuseport = ctx.no_reuseport;
1427 : } else {
1428 0 : selected_sk = ERR_PTR(-ECONNREFUSED);
1429 : }
1430 : }
1431 0 : rcu_read_unlock();
1432 0 : *psk = selected_sk;
1433 0 : return no_reuseport;
1434 : }
1435 :
1436 : #if IS_ENABLED(CONFIG_IPV6)
1437 : static inline bool bpf_sk_lookup_run_v6(struct net *net, int protocol,
1438 : const struct in6_addr *saddr,
1439 : const __be16 sport,
1440 : const struct in6_addr *daddr,
1441 : const u16 dport,
1442 : struct sock **psk)
1443 : {
1444 : struct bpf_prog_array *run_array;
1445 : struct sock *selected_sk = NULL;
1446 : bool no_reuseport = false;
1447 :
1448 : rcu_read_lock();
1449 : run_array = rcu_dereference(net->bpf.run_array[NETNS_BPF_SK_LOOKUP]);
1450 : if (run_array) {
1451 : struct bpf_sk_lookup_kern ctx = {
1452 : .family = AF_INET6,
1453 : .protocol = protocol,
1454 : .v6.saddr = saddr,
1455 : .v6.daddr = daddr,
1456 : .sport = sport,
1457 : .dport = dport,
1458 : };
1459 : u32 act;
1460 :
1461 : act = BPF_PROG_SK_LOOKUP_RUN_ARRAY(run_array, ctx, BPF_PROG_RUN);
1462 : if (act == SK_PASS) {
1463 : selected_sk = ctx.selected_sk;
1464 : no_reuseport = ctx.no_reuseport;
1465 : } else {
1466 : selected_sk = ERR_PTR(-ECONNREFUSED);
1467 : }
1468 : }
1469 : rcu_read_unlock();
1470 : *psk = selected_sk;
1471 : return no_reuseport;
1472 : }
1473 : #endif /* IS_ENABLED(CONFIG_IPV6) */
1474 :
1475 : #endif /* __LINUX_FILTER_H__ */
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