xref: /linux/include/linux/filter.h (revision 84b9b44b)
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 <linux/atomic.h>
9 #include <linux/bpf.h>
10 #include <linux/refcount.h>
11 #include <linux/compat.h>
12 #include <linux/skbuff.h>
13 #include <linux/linkage.h>
14 #include <linux/printk.h>
15 #include <linux/workqueue.h>
16 #include <linux/sched.h>
17 #include <linux/sched/clock.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 
32 struct sk_buff;
33 struct sock;
34 struct seccomp_data;
35 struct bpf_prog_aux;
36 struct xdp_rxq_info;
37 struct xdp_buff;
38 struct sock_reuseport;
39 struct ctl_table;
40 struct ctl_table_header;
41 
42 /* ArgX, context and stack frame pointer register positions. Note,
43  * Arg1, Arg2, Arg3, etc are used as argument mappings of function
44  * calls in BPF_CALL instruction.
45  */
46 #define BPF_REG_ARG1	BPF_REG_1
47 #define BPF_REG_ARG2	BPF_REG_2
48 #define BPF_REG_ARG3	BPF_REG_3
49 #define BPF_REG_ARG4	BPF_REG_4
50 #define BPF_REG_ARG5	BPF_REG_5
51 #define BPF_REG_CTX	BPF_REG_6
52 #define BPF_REG_FP	BPF_REG_10
53 
54 /* Additional register mappings for converted user programs. */
55 #define BPF_REG_A	BPF_REG_0
56 #define BPF_REG_X	BPF_REG_7
57 #define BPF_REG_TMP	BPF_REG_2	/* scratch reg */
58 #define BPF_REG_D	BPF_REG_8	/* data, callee-saved */
59 #define BPF_REG_H	BPF_REG_9	/* hlen, callee-saved */
60 
61 /* Kernel hidden auxiliary/helper register. */
62 #define BPF_REG_AX		MAX_BPF_REG
63 #define MAX_BPF_EXT_REG		(MAX_BPF_REG + 1)
64 #define MAX_BPF_JIT_REG		MAX_BPF_EXT_REG
65 
66 /* unused opcode to mark special call to bpf_tail_call() helper */
67 #define BPF_TAIL_CALL	0xf0
68 
69 /* unused opcode to mark special load instruction. Same as BPF_ABS */
70 #define BPF_PROBE_MEM	0x20
71 
72 /* unused opcode to mark call to interpreter with arguments */
73 #define BPF_CALL_ARGS	0xe0
74 
75 /* unused opcode to mark speculation barrier for mitigating
76  * Speculative Store Bypass
77  */
78 #define BPF_NOSPEC	0xc0
79 
80 /* As per nm, we expose JITed images as text (code) section for
81  * kallsyms. That way, tools like perf can find it to match
82  * addresses.
83  */
84 #define BPF_SYM_ELF_TYPE	't'
85 
86 /* BPF program can access up to 512 bytes of stack space. */
87 #define MAX_BPF_STACK	512
88 
89 /* Helper macros for filter block array initializers. */
90 
91 /* ALU ops on registers, bpf_add|sub|...: dst_reg += src_reg */
92 
93 #define BPF_ALU64_REG(OP, DST, SRC)				\
94 	((struct bpf_insn) {					\
95 		.code  = BPF_ALU64 | BPF_OP(OP) | BPF_X,	\
96 		.dst_reg = DST,					\
97 		.src_reg = SRC,					\
98 		.off   = 0,					\
99 		.imm   = 0 })
100 
101 #define BPF_ALU32_REG(OP, DST, SRC)				\
102 	((struct bpf_insn) {					\
103 		.code  = BPF_ALU | BPF_OP(OP) | BPF_X,		\
104 		.dst_reg = DST,					\
105 		.src_reg = SRC,					\
106 		.off   = 0,					\
107 		.imm   = 0 })
108 
109 /* ALU ops on immediates, bpf_add|sub|...: dst_reg += imm32 */
110 
111 #define BPF_ALU64_IMM(OP, DST, IMM)				\
112 	((struct bpf_insn) {					\
113 		.code  = BPF_ALU64 | BPF_OP(OP) | BPF_K,	\
114 		.dst_reg = DST,					\
115 		.src_reg = 0,					\
116 		.off   = 0,					\
117 		.imm   = IMM })
118 
119 #define BPF_ALU32_IMM(OP, DST, IMM)				\
120 	((struct bpf_insn) {					\
121 		.code  = BPF_ALU | BPF_OP(OP) | BPF_K,		\
122 		.dst_reg = DST,					\
123 		.src_reg = 0,					\
124 		.off   = 0,					\
125 		.imm   = IMM })
126 
127 /* Endianess conversion, cpu_to_{l,b}e(), {l,b}e_to_cpu() */
128 
129 #define BPF_ENDIAN(TYPE, DST, LEN)				\
130 	((struct bpf_insn) {					\
131 		.code  = BPF_ALU | BPF_END | BPF_SRC(TYPE),	\
132 		.dst_reg = DST,					\
133 		.src_reg = 0,					\
134 		.off   = 0,					\
135 		.imm   = LEN })
136 
137 /* Short form of mov, dst_reg = src_reg */
138 
139 #define BPF_MOV64_REG(DST, SRC)					\
140 	((struct bpf_insn) {					\
141 		.code  = BPF_ALU64 | BPF_MOV | BPF_X,		\
142 		.dst_reg = DST,					\
143 		.src_reg = SRC,					\
144 		.off   = 0,					\
145 		.imm   = 0 })
146 
147 #define BPF_MOV32_REG(DST, SRC)					\
148 	((struct bpf_insn) {					\
149 		.code  = BPF_ALU | BPF_MOV | BPF_X,		\
150 		.dst_reg = DST,					\
151 		.src_reg = SRC,					\
152 		.off   = 0,					\
153 		.imm   = 0 })
154 
155 /* Short form of mov, dst_reg = imm32 */
156 
157 #define BPF_MOV64_IMM(DST, IMM)					\
158 	((struct bpf_insn) {					\
159 		.code  = BPF_ALU64 | BPF_MOV | BPF_K,		\
160 		.dst_reg = DST,					\
161 		.src_reg = 0,					\
162 		.off   = 0,					\
163 		.imm   = IMM })
164 
165 #define BPF_MOV32_IMM(DST, IMM)					\
166 	((struct bpf_insn) {					\
167 		.code  = BPF_ALU | BPF_MOV | BPF_K,		\
168 		.dst_reg = DST,					\
169 		.src_reg = 0,					\
170 		.off   = 0,					\
171 		.imm   = IMM })
172 
173 /* Special form of mov32, used for doing explicit zero extension on dst. */
174 #define BPF_ZEXT_REG(DST)					\
175 	((struct bpf_insn) {					\
176 		.code  = BPF_ALU | BPF_MOV | BPF_X,		\
177 		.dst_reg = DST,					\
178 		.src_reg = DST,					\
179 		.off   = 0,					\
180 		.imm   = 1 })
181 
182 static inline bool insn_is_zext(const struct bpf_insn *insn)
183 {
184 	return insn->code == (BPF_ALU | BPF_MOV | BPF_X) && insn->imm == 1;
185 }
186 
187 /* BPF_LD_IMM64 macro encodes single 'load 64-bit immediate' insn */
188 #define BPF_LD_IMM64(DST, IMM)					\
189 	BPF_LD_IMM64_RAW(DST, 0, IMM)
190 
191 #define BPF_LD_IMM64_RAW(DST, SRC, IMM)				\
192 	((struct bpf_insn) {					\
193 		.code  = BPF_LD | BPF_DW | BPF_IMM,		\
194 		.dst_reg = DST,					\
195 		.src_reg = SRC,					\
196 		.off   = 0,					\
197 		.imm   = (__u32) (IMM) }),			\
198 	((struct bpf_insn) {					\
199 		.code  = 0, /* zero is reserved opcode */	\
200 		.dst_reg = 0,					\
201 		.src_reg = 0,					\
202 		.off   = 0,					\
203 		.imm   = ((__u64) (IMM)) >> 32 })
204 
205 /* pseudo BPF_LD_IMM64 insn used to refer to process-local map_fd */
206 #define BPF_LD_MAP_FD(DST, MAP_FD)				\
207 	BPF_LD_IMM64_RAW(DST, BPF_PSEUDO_MAP_FD, MAP_FD)
208 
209 /* Short form of mov based on type, BPF_X: dst_reg = src_reg, BPF_K: dst_reg = imm32 */
210 
211 #define BPF_MOV64_RAW(TYPE, DST, SRC, IMM)			\
212 	((struct bpf_insn) {					\
213 		.code  = BPF_ALU64 | BPF_MOV | BPF_SRC(TYPE),	\
214 		.dst_reg = DST,					\
215 		.src_reg = SRC,					\
216 		.off   = 0,					\
217 		.imm   = IMM })
218 
219 #define BPF_MOV32_RAW(TYPE, DST, SRC, IMM)			\
220 	((struct bpf_insn) {					\
221 		.code  = BPF_ALU | BPF_MOV | BPF_SRC(TYPE),	\
222 		.dst_reg = DST,					\
223 		.src_reg = SRC,					\
224 		.off   = 0,					\
225 		.imm   = IMM })
226 
227 /* Direct packet access, R0 = *(uint *) (skb->data + imm32) */
228 
229 #define BPF_LD_ABS(SIZE, IMM)					\
230 	((struct bpf_insn) {					\
231 		.code  = BPF_LD | BPF_SIZE(SIZE) | BPF_ABS,	\
232 		.dst_reg = 0,					\
233 		.src_reg = 0,					\
234 		.off   = 0,					\
235 		.imm   = IMM })
236 
237 /* Indirect packet access, R0 = *(uint *) (skb->data + src_reg + imm32) */
238 
239 #define BPF_LD_IND(SIZE, SRC, IMM)				\
240 	((struct bpf_insn) {					\
241 		.code  = BPF_LD | BPF_SIZE(SIZE) | BPF_IND,	\
242 		.dst_reg = 0,					\
243 		.src_reg = SRC,					\
244 		.off   = 0,					\
245 		.imm   = IMM })
246 
247 /* Memory load, dst_reg = *(uint *) (src_reg + off16) */
248 
249 #define BPF_LDX_MEM(SIZE, DST, SRC, OFF)			\
250 	((struct bpf_insn) {					\
251 		.code  = BPF_LDX | BPF_SIZE(SIZE) | BPF_MEM,	\
252 		.dst_reg = DST,					\
253 		.src_reg = SRC,					\
254 		.off   = OFF,					\
255 		.imm   = 0 })
256 
257 /* Memory store, *(uint *) (dst_reg + off16) = src_reg */
258 
259 #define BPF_STX_MEM(SIZE, DST, SRC, OFF)			\
260 	((struct bpf_insn) {					\
261 		.code  = BPF_STX | BPF_SIZE(SIZE) | BPF_MEM,	\
262 		.dst_reg = DST,					\
263 		.src_reg = SRC,					\
264 		.off   = OFF,					\
265 		.imm   = 0 })
266 
267 
268 /*
269  * Atomic operations:
270  *
271  *   BPF_ADD                  *(uint *) (dst_reg + off16) += src_reg
272  *   BPF_AND                  *(uint *) (dst_reg + off16) &= src_reg
273  *   BPF_OR                   *(uint *) (dst_reg + off16) |= src_reg
274  *   BPF_XOR                  *(uint *) (dst_reg + off16) ^= src_reg
275  *   BPF_ADD | BPF_FETCH      src_reg = atomic_fetch_add(dst_reg + off16, src_reg);
276  *   BPF_AND | BPF_FETCH      src_reg = atomic_fetch_and(dst_reg + off16, src_reg);
277  *   BPF_OR | BPF_FETCH       src_reg = atomic_fetch_or(dst_reg + off16, src_reg);
278  *   BPF_XOR | BPF_FETCH      src_reg = atomic_fetch_xor(dst_reg + off16, src_reg);
279  *   BPF_XCHG                 src_reg = atomic_xchg(dst_reg + off16, src_reg)
280  *   BPF_CMPXCHG              r0 = atomic_cmpxchg(dst_reg + off16, r0, src_reg)
281  */
282 
283 #define BPF_ATOMIC_OP(SIZE, OP, DST, SRC, OFF)			\
284 	((struct bpf_insn) {					\
285 		.code  = BPF_STX | BPF_SIZE(SIZE) | BPF_ATOMIC,	\
286 		.dst_reg = DST,					\
287 		.src_reg = SRC,					\
288 		.off   = OFF,					\
289 		.imm   = OP })
290 
291 /* Legacy alias */
292 #define BPF_STX_XADD(SIZE, DST, SRC, OFF) BPF_ATOMIC_OP(SIZE, BPF_ADD, DST, SRC, OFF)
293 
294 /* Memory store, *(uint *) (dst_reg + off16) = imm32 */
295 
296 #define BPF_ST_MEM(SIZE, DST, OFF, IMM)				\
297 	((struct bpf_insn) {					\
298 		.code  = BPF_ST | BPF_SIZE(SIZE) | BPF_MEM,	\
299 		.dst_reg = DST,					\
300 		.src_reg = 0,					\
301 		.off   = OFF,					\
302 		.imm   = IMM })
303 
304 /* Conditional jumps against registers, if (dst_reg 'op' src_reg) goto pc + off16 */
305 
306 #define BPF_JMP_REG(OP, DST, SRC, OFF)				\
307 	((struct bpf_insn) {					\
308 		.code  = BPF_JMP | BPF_OP(OP) | BPF_X,		\
309 		.dst_reg = DST,					\
310 		.src_reg = SRC,					\
311 		.off   = OFF,					\
312 		.imm   = 0 })
313 
314 /* Conditional jumps against immediates, if (dst_reg 'op' imm32) goto pc + off16 */
315 
316 #define BPF_JMP_IMM(OP, DST, IMM, OFF)				\
317 	((struct bpf_insn) {					\
318 		.code  = BPF_JMP | BPF_OP(OP) | BPF_K,		\
319 		.dst_reg = DST,					\
320 		.src_reg = 0,					\
321 		.off   = OFF,					\
322 		.imm   = IMM })
323 
324 /* Like BPF_JMP_REG, but with 32-bit wide operands for comparison. */
325 
326 #define BPF_JMP32_REG(OP, DST, SRC, OFF)			\
327 	((struct bpf_insn) {					\
328 		.code  = BPF_JMP32 | BPF_OP(OP) | BPF_X,	\
329 		.dst_reg = DST,					\
330 		.src_reg = SRC,					\
331 		.off   = OFF,					\
332 		.imm   = 0 })
333 
334 /* Like BPF_JMP_IMM, but with 32-bit wide operands for comparison. */
335 
336 #define BPF_JMP32_IMM(OP, DST, IMM, OFF)			\
337 	((struct bpf_insn) {					\
338 		.code  = BPF_JMP32 | BPF_OP(OP) | BPF_K,	\
339 		.dst_reg = DST,					\
340 		.src_reg = 0,					\
341 		.off   = OFF,					\
342 		.imm   = IMM })
343 
344 /* Unconditional jumps, goto pc + off16 */
345 
346 #define BPF_JMP_A(OFF)						\
347 	((struct bpf_insn) {					\
348 		.code  = BPF_JMP | BPF_JA,			\
349 		.dst_reg = 0,					\
350 		.src_reg = 0,					\
351 		.off   = OFF,					\
352 		.imm   = 0 })
353 
354 /* Relative call */
355 
356 #define BPF_CALL_REL(TGT)					\
357 	((struct bpf_insn) {					\
358 		.code  = BPF_JMP | BPF_CALL,			\
359 		.dst_reg = 0,					\
360 		.src_reg = BPF_PSEUDO_CALL,			\
361 		.off   = 0,					\
362 		.imm   = TGT })
363 
364 /* Convert function address to BPF immediate */
365 
366 #define BPF_CALL_IMM(x)	((void *)(x) - (void *)__bpf_call_base)
367 
368 #define BPF_EMIT_CALL(FUNC)					\
369 	((struct bpf_insn) {					\
370 		.code  = BPF_JMP | BPF_CALL,			\
371 		.dst_reg = 0,					\
372 		.src_reg = 0,					\
373 		.off   = 0,					\
374 		.imm   = BPF_CALL_IMM(FUNC) })
375 
376 /* Raw code statement block */
377 
378 #define BPF_RAW_INSN(CODE, DST, SRC, OFF, IMM)			\
379 	((struct bpf_insn) {					\
380 		.code  = CODE,					\
381 		.dst_reg = DST,					\
382 		.src_reg = SRC,					\
383 		.off   = OFF,					\
384 		.imm   = IMM })
385 
386 /* Program exit */
387 
388 #define BPF_EXIT_INSN()						\
389 	((struct bpf_insn) {					\
390 		.code  = BPF_JMP | BPF_EXIT,			\
391 		.dst_reg = 0,					\
392 		.src_reg = 0,					\
393 		.off   = 0,					\
394 		.imm   = 0 })
395 
396 /* Speculation barrier */
397 
398 #define BPF_ST_NOSPEC()						\
399 	((struct bpf_insn) {					\
400 		.code  = BPF_ST | BPF_NOSPEC,			\
401 		.dst_reg = 0,					\
402 		.src_reg = 0,					\
403 		.off   = 0,					\
404 		.imm   = 0 })
405 
406 /* Internal classic blocks for direct assignment */
407 
408 #define __BPF_STMT(CODE, K)					\
409 	((struct sock_filter) BPF_STMT(CODE, K))
410 
411 #define __BPF_JUMP(CODE, K, JT, JF)				\
412 	((struct sock_filter) BPF_JUMP(CODE, K, JT, JF))
413 
414 #define bytes_to_bpf_size(bytes)				\
415 ({								\
416 	int bpf_size = -EINVAL;					\
417 								\
418 	if (bytes == sizeof(u8))				\
419 		bpf_size = BPF_B;				\
420 	else if (bytes == sizeof(u16))				\
421 		bpf_size = BPF_H;				\
422 	else if (bytes == sizeof(u32))				\
423 		bpf_size = BPF_W;				\
424 	else if (bytes == sizeof(u64))				\
425 		bpf_size = BPF_DW;				\
426 								\
427 	bpf_size;						\
428 })
429 
430 #define bpf_size_to_bytes(bpf_size)				\
431 ({								\
432 	int bytes = -EINVAL;					\
433 								\
434 	if (bpf_size == BPF_B)					\
435 		bytes = sizeof(u8);				\
436 	else if (bpf_size == BPF_H)				\
437 		bytes = sizeof(u16);				\
438 	else if (bpf_size == BPF_W)				\
439 		bytes = sizeof(u32);				\
440 	else if (bpf_size == BPF_DW)				\
441 		bytes = sizeof(u64);				\
442 								\
443 	bytes;							\
444 })
445 
446 #define BPF_SIZEOF(type)					\
447 	({							\
448 		const int __size = bytes_to_bpf_size(sizeof(type)); \
449 		BUILD_BUG_ON(__size < 0);			\
450 		__size;						\
451 	})
452 
453 #define BPF_FIELD_SIZEOF(type, field)				\
454 	({							\
455 		const int __size = bytes_to_bpf_size(sizeof_field(type, field)); \
456 		BUILD_BUG_ON(__size < 0);			\
457 		__size;						\
458 	})
459 
460 #define BPF_LDST_BYTES(insn)					\
461 	({							\
462 		const int __size = bpf_size_to_bytes(BPF_SIZE((insn)->code)); \
463 		WARN_ON(__size < 0);				\
464 		__size;						\
465 	})
466 
467 #define __BPF_MAP_0(m, v, ...) v
468 #define __BPF_MAP_1(m, v, t, a, ...) m(t, a)
469 #define __BPF_MAP_2(m, v, t, a, ...) m(t, a), __BPF_MAP_1(m, v, __VA_ARGS__)
470 #define __BPF_MAP_3(m, v, t, a, ...) m(t, a), __BPF_MAP_2(m, v, __VA_ARGS__)
471 #define __BPF_MAP_4(m, v, t, a, ...) m(t, a), __BPF_MAP_3(m, v, __VA_ARGS__)
472 #define __BPF_MAP_5(m, v, t, a, ...) m(t, a), __BPF_MAP_4(m, v, __VA_ARGS__)
473 
474 #define __BPF_REG_0(...) __BPF_PAD(5)
475 #define __BPF_REG_1(...) __BPF_MAP(1, __VA_ARGS__), __BPF_PAD(4)
476 #define __BPF_REG_2(...) __BPF_MAP(2, __VA_ARGS__), __BPF_PAD(3)
477 #define __BPF_REG_3(...) __BPF_MAP(3, __VA_ARGS__), __BPF_PAD(2)
478 #define __BPF_REG_4(...) __BPF_MAP(4, __VA_ARGS__), __BPF_PAD(1)
479 #define __BPF_REG_5(...) __BPF_MAP(5, __VA_ARGS__)
480 
481 #define __BPF_MAP(n, ...) __BPF_MAP_##n(__VA_ARGS__)
482 #define __BPF_REG(n, ...) __BPF_REG_##n(__VA_ARGS__)
483 
484 #define __BPF_CAST(t, a)						       \
485 	(__force t)							       \
486 	(__force							       \
487 	 typeof(__builtin_choose_expr(sizeof(t) == sizeof(unsigned long),      \
488 				      (unsigned long)0, (t)0))) a
489 #define __BPF_V void
490 #define __BPF_N
491 
492 #define __BPF_DECL_ARGS(t, a) t   a
493 #define __BPF_DECL_REGS(t, a) u64 a
494 
495 #define __BPF_PAD(n)							       \
496 	__BPF_MAP(n, __BPF_DECL_ARGS, __BPF_N, u64, __ur_1, u64, __ur_2,       \
497 		  u64, __ur_3, u64, __ur_4, u64, __ur_5)
498 
499 #define BPF_CALL_x(x, name, ...)					       \
500 	static __always_inline						       \
501 	u64 ____##name(__BPF_MAP(x, __BPF_DECL_ARGS, __BPF_V, __VA_ARGS__));   \
502 	typedef u64 (*btf_##name)(__BPF_MAP(x, __BPF_DECL_ARGS, __BPF_V, __VA_ARGS__)); \
503 	u64 name(__BPF_REG(x, __BPF_DECL_REGS, __BPF_N, __VA_ARGS__));	       \
504 	u64 name(__BPF_REG(x, __BPF_DECL_REGS, __BPF_N, __VA_ARGS__))	       \
505 	{								       \
506 		return ((btf_##name)____##name)(__BPF_MAP(x,__BPF_CAST,__BPF_N,__VA_ARGS__));\
507 	}								       \
508 	static __always_inline						       \
509 	u64 ____##name(__BPF_MAP(x, __BPF_DECL_ARGS, __BPF_V, __VA_ARGS__))
510 
511 #define BPF_CALL_0(name, ...)	BPF_CALL_x(0, name, __VA_ARGS__)
512 #define BPF_CALL_1(name, ...)	BPF_CALL_x(1, name, __VA_ARGS__)
513 #define BPF_CALL_2(name, ...)	BPF_CALL_x(2, name, __VA_ARGS__)
514 #define BPF_CALL_3(name, ...)	BPF_CALL_x(3, name, __VA_ARGS__)
515 #define BPF_CALL_4(name, ...)	BPF_CALL_x(4, name, __VA_ARGS__)
516 #define BPF_CALL_5(name, ...)	BPF_CALL_x(5, name, __VA_ARGS__)
517 
518 #define bpf_ctx_range(TYPE, MEMBER)						\
519 	offsetof(TYPE, MEMBER) ... offsetofend(TYPE, MEMBER) - 1
520 #define bpf_ctx_range_till(TYPE, MEMBER1, MEMBER2)				\
521 	offsetof(TYPE, MEMBER1) ... offsetofend(TYPE, MEMBER2) - 1
522 #if BITS_PER_LONG == 64
523 # define bpf_ctx_range_ptr(TYPE, MEMBER)					\
524 	offsetof(TYPE, MEMBER) ... offsetofend(TYPE, MEMBER) - 1
525 #else
526 # define bpf_ctx_range_ptr(TYPE, MEMBER)					\
527 	offsetof(TYPE, MEMBER) ... offsetof(TYPE, MEMBER) + 8 - 1
528 #endif /* BITS_PER_LONG == 64 */
529 
530 #define bpf_target_off(TYPE, MEMBER, SIZE, PTR_SIZE)				\
531 	({									\
532 		BUILD_BUG_ON(sizeof_field(TYPE, MEMBER) != (SIZE));		\
533 		*(PTR_SIZE) = (SIZE);						\
534 		offsetof(TYPE, MEMBER);						\
535 	})
536 
537 /* A struct sock_filter is architecture independent. */
538 struct compat_sock_fprog {
539 	u16		len;
540 	compat_uptr_t	filter;	/* struct sock_filter * */
541 };
542 
543 struct sock_fprog_kern {
544 	u16			len;
545 	struct sock_filter	*filter;
546 };
547 
548 /* Some arches need doubleword alignment for their instructions and/or data */
549 #define BPF_IMAGE_ALIGNMENT 8
550 
551 struct bpf_binary_header {
552 	u32 size;
553 	u8 image[] __aligned(BPF_IMAGE_ALIGNMENT);
554 };
555 
556 struct bpf_prog_stats {
557 	u64_stats_t cnt;
558 	u64_stats_t nsecs;
559 	u64_stats_t misses;
560 	struct u64_stats_sync syncp;
561 } __aligned(2 * sizeof(u64));
562 
563 struct sk_filter {
564 	refcount_t	refcnt;
565 	struct rcu_head	rcu;
566 	struct bpf_prog	*prog;
567 };
568 
569 DECLARE_STATIC_KEY_FALSE(bpf_stats_enabled_key);
570 
571 extern struct mutex nf_conn_btf_access_lock;
572 extern int (*nfct_btf_struct_access)(struct bpf_verifier_log *log,
573 				     const struct bpf_reg_state *reg,
574 				     int off, int size);
575 
576 typedef unsigned int (*bpf_dispatcher_fn)(const void *ctx,
577 					  const struct bpf_insn *insnsi,
578 					  unsigned int (*bpf_func)(const void *,
579 								   const struct bpf_insn *));
580 
581 static __always_inline u32 __bpf_prog_run(const struct bpf_prog *prog,
582 					  const void *ctx,
583 					  bpf_dispatcher_fn dfunc)
584 {
585 	u32 ret;
586 
587 	cant_migrate();
588 	if (static_branch_unlikely(&bpf_stats_enabled_key)) {
589 		struct bpf_prog_stats *stats;
590 		u64 start = sched_clock();
591 		unsigned long flags;
592 
593 		ret = dfunc(ctx, prog->insnsi, prog->bpf_func);
594 		stats = this_cpu_ptr(prog->stats);
595 		flags = u64_stats_update_begin_irqsave(&stats->syncp);
596 		u64_stats_inc(&stats->cnt);
597 		u64_stats_add(&stats->nsecs, sched_clock() - start);
598 		u64_stats_update_end_irqrestore(&stats->syncp, flags);
599 	} else {
600 		ret = dfunc(ctx, prog->insnsi, prog->bpf_func);
601 	}
602 	return ret;
603 }
604 
605 static __always_inline u32 bpf_prog_run(const struct bpf_prog *prog, const void *ctx)
606 {
607 	return __bpf_prog_run(prog, ctx, bpf_dispatcher_nop_func);
608 }
609 
610 /*
611  * Use in preemptible and therefore migratable context to make sure that
612  * the execution of the BPF program runs on one CPU.
613  *
614  * This uses migrate_disable/enable() explicitly to document that the
615  * invocation of a BPF program does not require reentrancy protection
616  * against a BPF program which is invoked from a preempting task.
617  */
618 static inline u32 bpf_prog_run_pin_on_cpu(const struct bpf_prog *prog,
619 					  const void *ctx)
620 {
621 	u32 ret;
622 
623 	migrate_disable();
624 	ret = bpf_prog_run(prog, ctx);
625 	migrate_enable();
626 	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 	u64 tgt_index;
647 	void *tgt_value;
648 	struct bpf_map *map;
649 	u32 flags;
650 	u32 kern_flags;
651 	u32 map_id;
652 	enum bpf_map_type map_type;
653 	struct bpf_nh_params nh;
654 };
655 
656 DECLARE_PER_CPU(struct bpf_redirect_info, bpf_redirect_info);
657 
658 /* flags for bpf_redirect_info kern_flags */
659 #define BPF_RI_F_RF_NO_DIRECT	BIT(0)	/* no napi_direct on return_frame */
660 
661 /* Compute the linear packet data range [data, data_end) which
662  * will be accessed by various program types (cls_bpf, act_bpf,
663  * lwt, ...). Subsystems allowing direct data access must (!)
664  * ensure that cb[] area can be written to when BPF program is
665  * invoked (otherwise cb[] save/restore is necessary).
666  */
667 static inline void bpf_compute_data_pointers(struct sk_buff *skb)
668 {
669 	struct bpf_skb_data_end *cb = (struct bpf_skb_data_end *)skb->cb;
670 
671 	BUILD_BUG_ON(sizeof(*cb) > sizeof_field(struct sk_buff, cb));
672 	cb->data_meta = skb->data - skb_metadata_len(skb);
673 	cb->data_end  = skb->data + skb_headlen(skb);
674 }
675 
676 /* Similar to bpf_compute_data_pointers(), except that save orginal
677  * data in cb->data and cb->meta_data for restore.
678  */
679 static inline void bpf_compute_and_save_data_end(
680 	struct sk_buff *skb, void **saved_data_end)
681 {
682 	struct bpf_skb_data_end *cb = (struct bpf_skb_data_end *)skb->cb;
683 
684 	*saved_data_end = cb->data_end;
685 	cb->data_end  = skb->data + skb_headlen(skb);
686 }
687 
688 /* Restore data saved by bpf_compute_data_pointers(). */
689 static inline void bpf_restore_data_end(
690 	struct sk_buff *skb, void *saved_data_end)
691 {
692 	struct bpf_skb_data_end *cb = (struct bpf_skb_data_end *)skb->cb;
693 
694 	cb->data_end = saved_data_end;
695 }
696 
697 static inline u8 *bpf_skb_cb(const struct sk_buff *skb)
698 {
699 	/* eBPF programs may read/write skb->cb[] area to transfer meta
700 	 * data between tail calls. Since this also needs to work with
701 	 * tc, that scratch memory is mapped to qdisc_skb_cb's data area.
702 	 *
703 	 * In some socket filter cases, the cb unfortunately needs to be
704 	 * saved/restored so that protocol specific skb->cb[] data won't
705 	 * be lost. In any case, due to unpriviledged eBPF programs
706 	 * attached to sockets, we need to clear the bpf_skb_cb() area
707 	 * to not leak previous contents to user space.
708 	 */
709 	BUILD_BUG_ON(sizeof_field(struct __sk_buff, cb) != BPF_SKB_CB_LEN);
710 	BUILD_BUG_ON(sizeof_field(struct __sk_buff, cb) !=
711 		     sizeof_field(struct qdisc_skb_cb, data));
712 
713 	return qdisc_skb_cb(skb)->data;
714 }
715 
716 /* Must be invoked with migration disabled */
717 static inline u32 __bpf_prog_run_save_cb(const struct bpf_prog *prog,
718 					 const void *ctx)
719 {
720 	const struct sk_buff *skb = ctx;
721 	u8 *cb_data = bpf_skb_cb(skb);
722 	u8 cb_saved[BPF_SKB_CB_LEN];
723 	u32 res;
724 
725 	if (unlikely(prog->cb_access)) {
726 		memcpy(cb_saved, cb_data, sizeof(cb_saved));
727 		memset(cb_data, 0, sizeof(cb_saved));
728 	}
729 
730 	res = bpf_prog_run(prog, skb);
731 
732 	if (unlikely(prog->cb_access))
733 		memcpy(cb_data, cb_saved, sizeof(cb_saved));
734 
735 	return res;
736 }
737 
738 static inline u32 bpf_prog_run_save_cb(const struct bpf_prog *prog,
739 				       struct sk_buff *skb)
740 {
741 	u32 res;
742 
743 	migrate_disable();
744 	res = __bpf_prog_run_save_cb(prog, skb);
745 	migrate_enable();
746 	return res;
747 }
748 
749 static inline u32 bpf_prog_run_clear_cb(const struct bpf_prog *prog,
750 					struct sk_buff *skb)
751 {
752 	u8 *cb_data = bpf_skb_cb(skb);
753 	u32 res;
754 
755 	if (unlikely(prog->cb_access))
756 		memset(cb_data, 0, BPF_SKB_CB_LEN);
757 
758 	res = bpf_prog_run_pin_on_cpu(prog, skb);
759 	return res;
760 }
761 
762 DECLARE_BPF_DISPATCHER(xdp)
763 
764 DECLARE_STATIC_KEY_FALSE(bpf_master_redirect_enabled_key);
765 
766 u32 xdp_master_redirect(struct xdp_buff *xdp);
767 
768 static __always_inline u32 bpf_prog_run_xdp(const struct bpf_prog *prog,
769 					    struct xdp_buff *xdp)
770 {
771 	/* Driver XDP hooks are invoked within a single NAPI poll cycle and thus
772 	 * under local_bh_disable(), which provides the needed RCU protection
773 	 * for accessing map entries.
774 	 */
775 	u32 act = __bpf_prog_run(prog, xdp, BPF_DISPATCHER_FUNC(xdp));
776 
777 	if (static_branch_unlikely(&bpf_master_redirect_enabled_key)) {
778 		if (act == XDP_TX && netif_is_bond_slave(xdp->rxq->dev))
779 			act = xdp_master_redirect(xdp);
780 	}
781 
782 	return act;
783 }
784 
785 void bpf_prog_change_xdp(struct bpf_prog *prev_prog, struct bpf_prog *prog);
786 
787 static inline u32 bpf_prog_insn_size(const struct bpf_prog *prog)
788 {
789 	return prog->len * sizeof(struct bpf_insn);
790 }
791 
792 static inline u32 bpf_prog_tag_scratch_size(const struct bpf_prog *prog)
793 {
794 	return round_up(bpf_prog_insn_size(prog) +
795 			sizeof(__be64) + 1, SHA1_BLOCK_SIZE);
796 }
797 
798 static inline unsigned int bpf_prog_size(unsigned int proglen)
799 {
800 	return max(sizeof(struct bpf_prog),
801 		   offsetof(struct bpf_prog, insns[proglen]));
802 }
803 
804 static inline bool bpf_prog_was_classic(const struct bpf_prog *prog)
805 {
806 	/* When classic BPF programs have been loaded and the arch
807 	 * does not have a classic BPF JIT (anymore), they have been
808 	 * converted via bpf_migrate_filter() to eBPF and thus always
809 	 * have an unspec program type.
810 	 */
811 	return prog->type == BPF_PROG_TYPE_UNSPEC;
812 }
813 
814 static inline u32 bpf_ctx_off_adjust_machine(u32 size)
815 {
816 	const u32 size_machine = sizeof(unsigned long);
817 
818 	if (size > size_machine && size % size_machine == 0)
819 		size = size_machine;
820 
821 	return size;
822 }
823 
824 static inline bool
825 bpf_ctx_narrow_access_ok(u32 off, u32 size, u32 size_default)
826 {
827 	return size <= size_default && (size & (size - 1)) == 0;
828 }
829 
830 static inline u8
831 bpf_ctx_narrow_access_offset(u32 off, u32 size, u32 size_default)
832 {
833 	u8 access_off = off & (size_default - 1);
834 
835 #ifdef __LITTLE_ENDIAN
836 	return access_off;
837 #else
838 	return size_default - (access_off + size);
839 #endif
840 }
841 
842 #define bpf_ctx_wide_access_ok(off, size, type, field)			\
843 	(size == sizeof(__u64) &&					\
844 	off >= offsetof(type, field) &&					\
845 	off + sizeof(__u64) <= offsetofend(type, field) &&		\
846 	off % sizeof(__u64) == 0)
847 
848 #define bpf_classic_proglen(fprog) (fprog->len * sizeof(fprog->filter[0]))
849 
850 static inline void bpf_prog_lock_ro(struct bpf_prog *fp)
851 {
852 #ifndef CONFIG_BPF_JIT_ALWAYS_ON
853 	if (!fp->jited) {
854 		set_vm_flush_reset_perms(fp);
855 		set_memory_ro((unsigned long)fp, fp->pages);
856 	}
857 #endif
858 }
859 
860 static inline void bpf_jit_binary_lock_ro(struct bpf_binary_header *hdr)
861 {
862 	set_vm_flush_reset_perms(hdr);
863 	set_memory_rox((unsigned long)hdr, hdr->size >> PAGE_SHIFT);
864 }
865 
866 int sk_filter_trim_cap(struct sock *sk, struct sk_buff *skb, unsigned int cap);
867 static inline int sk_filter(struct sock *sk, struct sk_buff *skb)
868 {
869 	return sk_filter_trim_cap(sk, skb, 1);
870 }
871 
872 struct bpf_prog *bpf_prog_select_runtime(struct bpf_prog *fp, int *err);
873 void bpf_prog_free(struct bpf_prog *fp);
874 
875 bool bpf_opcode_in_insntable(u8 code);
876 
877 void bpf_prog_free_linfo(struct bpf_prog *prog);
878 void bpf_prog_fill_jited_linfo(struct bpf_prog *prog,
879 			       const u32 *insn_to_jit_off);
880 int bpf_prog_alloc_jited_linfo(struct bpf_prog *prog);
881 void bpf_prog_jit_attempt_done(struct bpf_prog *prog);
882 
883 struct bpf_prog *bpf_prog_alloc(unsigned int size, gfp_t gfp_extra_flags);
884 struct bpf_prog *bpf_prog_alloc_no_stats(unsigned int size, gfp_t gfp_extra_flags);
885 struct bpf_prog *bpf_prog_realloc(struct bpf_prog *fp_old, unsigned int size,
886 				  gfp_t gfp_extra_flags);
887 void __bpf_prog_free(struct bpf_prog *fp);
888 
889 static inline void bpf_prog_unlock_free(struct bpf_prog *fp)
890 {
891 	__bpf_prog_free(fp);
892 }
893 
894 typedef int (*bpf_aux_classic_check_t)(struct sock_filter *filter,
895 				       unsigned int flen);
896 
897 int bpf_prog_create(struct bpf_prog **pfp, struct sock_fprog_kern *fprog);
898 int bpf_prog_create_from_user(struct bpf_prog **pfp, struct sock_fprog *fprog,
899 			      bpf_aux_classic_check_t trans, bool save_orig);
900 void bpf_prog_destroy(struct bpf_prog *fp);
901 
902 int sk_attach_filter(struct sock_fprog *fprog, struct sock *sk);
903 int sk_attach_bpf(u32 ufd, struct sock *sk);
904 int sk_reuseport_attach_filter(struct sock_fprog *fprog, struct sock *sk);
905 int sk_reuseport_attach_bpf(u32 ufd, struct sock *sk);
906 void sk_reuseport_prog_free(struct bpf_prog *prog);
907 int sk_detach_filter(struct sock *sk);
908 int sk_get_filter(struct sock *sk, sockptr_t optval, 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_jit_supports_subprog_tailcalls(void);
922 bool bpf_jit_supports_kfunc_call(void);
923 bool bpf_jit_supports_far_kfunc_call(void);
924 bool bpf_helper_changes_pkt_data(void *func);
925 
926 static inline bool bpf_dump_raw_ok(const struct cred *cred)
927 {
928 	/* Reconstruction of call-sites is dependent on kallsyms,
929 	 * thus make dump the same restriction.
930 	 */
931 	return kallsyms_show_value(cred);
932 }
933 
934 struct bpf_prog *bpf_patch_insn_single(struct bpf_prog *prog, u32 off,
935 				       const struct bpf_insn *patch, u32 len);
936 int bpf_remove_insns(struct bpf_prog *prog, u32 off, u32 cnt);
937 
938 void bpf_clear_redirect_map(struct bpf_map *map);
939 
940 static inline bool xdp_return_frame_no_direct(void)
941 {
942 	struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
943 
944 	return ri->kern_flags & BPF_RI_F_RF_NO_DIRECT;
945 }
946 
947 static inline void xdp_set_return_frame_no_direct(void)
948 {
949 	struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
950 
951 	ri->kern_flags |= BPF_RI_F_RF_NO_DIRECT;
952 }
953 
954 static inline void xdp_clear_return_frame_no_direct(void)
955 {
956 	struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
957 
958 	ri->kern_flags &= ~BPF_RI_F_RF_NO_DIRECT;
959 }
960 
961 static inline int xdp_ok_fwd_dev(const struct net_device *fwd,
962 				 unsigned int pktlen)
963 {
964 	unsigned int len;
965 
966 	if (unlikely(!(fwd->flags & IFF_UP)))
967 		return -ENETDOWN;
968 
969 	len = fwd->mtu + fwd->hard_header_len + VLAN_HLEN;
970 	if (pktlen > len)
971 		return -EMSGSIZE;
972 
973 	return 0;
974 }
975 
976 /* The pair of xdp_do_redirect and xdp_do_flush MUST be called in the
977  * same cpu context. Further for best results no more than a single map
978  * for the do_redirect/do_flush pair should be used. This limitation is
979  * because we only track one map and force a flush when the map changes.
980  * This does not appear to be a real limitation for existing software.
981  */
982 int xdp_do_generic_redirect(struct net_device *dev, struct sk_buff *skb,
983 			    struct xdp_buff *xdp, struct bpf_prog *prog);
984 int xdp_do_redirect(struct net_device *dev,
985 		    struct xdp_buff *xdp,
986 		    struct bpf_prog *prog);
987 int xdp_do_redirect_frame(struct net_device *dev,
988 			  struct xdp_buff *xdp,
989 			  struct xdp_frame *xdpf,
990 			  struct bpf_prog *prog);
991 void xdp_do_flush(void);
992 
993 /* The xdp_do_flush_map() helper has been renamed to drop the _map suffix, as
994  * it is no longer only flushing maps. Keep this define for compatibility
995  * until all drivers are updated - do not use xdp_do_flush_map() in new code!
996  */
997 #define xdp_do_flush_map xdp_do_flush
998 
999 void bpf_warn_invalid_xdp_action(struct net_device *dev, struct bpf_prog *prog, u32 act);
1000 
1001 #ifdef CONFIG_INET
1002 struct sock *bpf_run_sk_reuseport(struct sock_reuseport *reuse, struct sock *sk,
1003 				  struct bpf_prog *prog, struct sk_buff *skb,
1004 				  struct sock *migrating_sk,
1005 				  u32 hash);
1006 #else
1007 static inline struct sock *
1008 bpf_run_sk_reuseport(struct sock_reuseport *reuse, struct sock *sk,
1009 		     struct bpf_prog *prog, struct sk_buff *skb,
1010 		     struct sock *migrating_sk,
1011 		     u32 hash)
1012 {
1013 	return NULL;
1014 }
1015 #endif
1016 
1017 #ifdef CONFIG_BPF_JIT
1018 extern int bpf_jit_enable;
1019 extern int bpf_jit_harden;
1020 extern int bpf_jit_kallsyms;
1021 extern long bpf_jit_limit;
1022 extern long bpf_jit_limit_max;
1023 
1024 typedef void (*bpf_jit_fill_hole_t)(void *area, unsigned int size);
1025 
1026 void bpf_jit_fill_hole_with_zero(void *area, unsigned int size);
1027 
1028 struct bpf_binary_header *
1029 bpf_jit_binary_alloc(unsigned int proglen, u8 **image_ptr,
1030 		     unsigned int alignment,
1031 		     bpf_jit_fill_hole_t bpf_fill_ill_insns);
1032 void bpf_jit_binary_free(struct bpf_binary_header *hdr);
1033 u64 bpf_jit_alloc_exec_limit(void);
1034 void *bpf_jit_alloc_exec(unsigned long size);
1035 void bpf_jit_free_exec(void *addr);
1036 void bpf_jit_free(struct bpf_prog *fp);
1037 struct bpf_binary_header *
1038 bpf_jit_binary_pack_hdr(const struct bpf_prog *fp);
1039 
1040 void *bpf_prog_pack_alloc(u32 size, bpf_jit_fill_hole_t bpf_fill_ill_insns);
1041 void bpf_prog_pack_free(struct bpf_binary_header *hdr);
1042 
1043 static inline bool bpf_prog_kallsyms_verify_off(const struct bpf_prog *fp)
1044 {
1045 	return list_empty(&fp->aux->ksym.lnode) ||
1046 	       fp->aux->ksym.lnode.prev == LIST_POISON2;
1047 }
1048 
1049 struct bpf_binary_header *
1050 bpf_jit_binary_pack_alloc(unsigned int proglen, u8 **ro_image,
1051 			  unsigned int alignment,
1052 			  struct bpf_binary_header **rw_hdr,
1053 			  u8 **rw_image,
1054 			  bpf_jit_fill_hole_t bpf_fill_ill_insns);
1055 int bpf_jit_binary_pack_finalize(struct bpf_prog *prog,
1056 				 struct bpf_binary_header *ro_header,
1057 				 struct bpf_binary_header *rw_header);
1058 void bpf_jit_binary_pack_free(struct bpf_binary_header *ro_header,
1059 			      struct bpf_binary_header *rw_header);
1060 
1061 int bpf_jit_add_poke_descriptor(struct bpf_prog *prog,
1062 				struct bpf_jit_poke_descriptor *poke);
1063 
1064 int bpf_jit_get_func_addr(const struct bpf_prog *prog,
1065 			  const struct bpf_insn *insn, bool extra_pass,
1066 			  u64 *func_addr, bool *func_addr_fixed);
1067 
1068 struct bpf_prog *bpf_jit_blind_constants(struct bpf_prog *fp);
1069 void bpf_jit_prog_release_other(struct bpf_prog *fp, struct bpf_prog *fp_other);
1070 
1071 static inline void bpf_jit_dump(unsigned int flen, unsigned int proglen,
1072 				u32 pass, void *image)
1073 {
1074 	pr_err("flen=%u proglen=%u pass=%u image=%pK from=%s pid=%d\n", flen,
1075 	       proglen, pass, image, current->comm, task_pid_nr(current));
1076 
1077 	if (image)
1078 		print_hex_dump(KERN_ERR, "JIT code: ", DUMP_PREFIX_OFFSET,
1079 			       16, 1, image, proglen, false);
1080 }
1081 
1082 static inline bool bpf_jit_is_ebpf(void)
1083 {
1084 # ifdef CONFIG_HAVE_EBPF_JIT
1085 	return true;
1086 # else
1087 	return false;
1088 # endif
1089 }
1090 
1091 static inline bool ebpf_jit_enabled(void)
1092 {
1093 	return bpf_jit_enable && bpf_jit_is_ebpf();
1094 }
1095 
1096 static inline bool bpf_prog_ebpf_jited(const struct bpf_prog *fp)
1097 {
1098 	return fp->jited && bpf_jit_is_ebpf();
1099 }
1100 
1101 static inline bool bpf_jit_blinding_enabled(struct bpf_prog *prog)
1102 {
1103 	/* These are the prerequisites, should someone ever have the
1104 	 * idea to call blinding outside of them, we make sure to
1105 	 * bail out.
1106 	 */
1107 	if (!bpf_jit_is_ebpf())
1108 		return false;
1109 	if (!prog->jit_requested)
1110 		return false;
1111 	if (!bpf_jit_harden)
1112 		return false;
1113 	if (bpf_jit_harden == 1 && bpf_capable())
1114 		return false;
1115 
1116 	return true;
1117 }
1118 
1119 static inline bool bpf_jit_kallsyms_enabled(void)
1120 {
1121 	/* There are a couple of corner cases where kallsyms should
1122 	 * not be enabled f.e. on hardening.
1123 	 */
1124 	if (bpf_jit_harden)
1125 		return false;
1126 	if (!bpf_jit_kallsyms)
1127 		return false;
1128 	if (bpf_jit_kallsyms == 1)
1129 		return true;
1130 
1131 	return false;
1132 }
1133 
1134 const char *__bpf_address_lookup(unsigned long addr, unsigned long *size,
1135 				 unsigned long *off, char *sym);
1136 bool is_bpf_text_address(unsigned long addr);
1137 int bpf_get_kallsym(unsigned int symnum, unsigned long *value, char *type,
1138 		    char *sym);
1139 
1140 static inline const char *
1141 bpf_address_lookup(unsigned long addr, unsigned long *size,
1142 		   unsigned long *off, char **modname, char *sym)
1143 {
1144 	const char *ret = __bpf_address_lookup(addr, size, off, sym);
1145 
1146 	if (ret && modname)
1147 		*modname = NULL;
1148 	return ret;
1149 }
1150 
1151 void bpf_prog_kallsyms_add(struct bpf_prog *fp);
1152 void bpf_prog_kallsyms_del(struct bpf_prog *fp);
1153 
1154 #else /* CONFIG_BPF_JIT */
1155 
1156 static inline bool ebpf_jit_enabled(void)
1157 {
1158 	return false;
1159 }
1160 
1161 static inline bool bpf_jit_blinding_enabled(struct bpf_prog *prog)
1162 {
1163 	return false;
1164 }
1165 
1166 static inline bool bpf_prog_ebpf_jited(const struct bpf_prog *fp)
1167 {
1168 	return false;
1169 }
1170 
1171 static inline int
1172 bpf_jit_add_poke_descriptor(struct bpf_prog *prog,
1173 			    struct bpf_jit_poke_descriptor *poke)
1174 {
1175 	return -ENOTSUPP;
1176 }
1177 
1178 static inline void bpf_jit_free(struct bpf_prog *fp)
1179 {
1180 	bpf_prog_unlock_free(fp);
1181 }
1182 
1183 static inline bool bpf_jit_kallsyms_enabled(void)
1184 {
1185 	return false;
1186 }
1187 
1188 static inline const char *
1189 __bpf_address_lookup(unsigned long addr, unsigned long *size,
1190 		     unsigned long *off, char *sym)
1191 {
1192 	return NULL;
1193 }
1194 
1195 static inline bool is_bpf_text_address(unsigned long addr)
1196 {
1197 	return false;
1198 }
1199 
1200 static inline int bpf_get_kallsym(unsigned int symnum, unsigned long *value,
1201 				  char *type, char *sym)
1202 {
1203 	return -ERANGE;
1204 }
1205 
1206 static inline const char *
1207 bpf_address_lookup(unsigned long addr, unsigned long *size,
1208 		   unsigned long *off, char **modname, char *sym)
1209 {
1210 	return NULL;
1211 }
1212 
1213 static inline void bpf_prog_kallsyms_add(struct bpf_prog *fp)
1214 {
1215 }
1216 
1217 static inline void bpf_prog_kallsyms_del(struct bpf_prog *fp)
1218 {
1219 }
1220 
1221 #endif /* CONFIG_BPF_JIT */
1222 
1223 void bpf_prog_kallsyms_del_all(struct bpf_prog *fp);
1224 
1225 #define BPF_ANC		BIT(15)
1226 
1227 static inline bool bpf_needs_clear_a(const struct sock_filter *first)
1228 {
1229 	switch (first->code) {
1230 	case BPF_RET | BPF_K:
1231 	case BPF_LD | BPF_W | BPF_LEN:
1232 		return false;
1233 
1234 	case BPF_LD | BPF_W | BPF_ABS:
1235 	case BPF_LD | BPF_H | BPF_ABS:
1236 	case BPF_LD | BPF_B | BPF_ABS:
1237 		if (first->k == SKF_AD_OFF + SKF_AD_ALU_XOR_X)
1238 			return true;
1239 		return false;
1240 
1241 	default:
1242 		return true;
1243 	}
1244 }
1245 
1246 static inline u16 bpf_anc_helper(const struct sock_filter *ftest)
1247 {
1248 	BUG_ON(ftest->code & BPF_ANC);
1249 
1250 	switch (ftest->code) {
1251 	case BPF_LD | BPF_W | BPF_ABS:
1252 	case BPF_LD | BPF_H | BPF_ABS:
1253 	case BPF_LD | BPF_B | BPF_ABS:
1254 #define BPF_ANCILLARY(CODE)	case SKF_AD_OFF + SKF_AD_##CODE:	\
1255 				return BPF_ANC | SKF_AD_##CODE
1256 		switch (ftest->k) {
1257 		BPF_ANCILLARY(PROTOCOL);
1258 		BPF_ANCILLARY(PKTTYPE);
1259 		BPF_ANCILLARY(IFINDEX);
1260 		BPF_ANCILLARY(NLATTR);
1261 		BPF_ANCILLARY(NLATTR_NEST);
1262 		BPF_ANCILLARY(MARK);
1263 		BPF_ANCILLARY(QUEUE);
1264 		BPF_ANCILLARY(HATYPE);
1265 		BPF_ANCILLARY(RXHASH);
1266 		BPF_ANCILLARY(CPU);
1267 		BPF_ANCILLARY(ALU_XOR_X);
1268 		BPF_ANCILLARY(VLAN_TAG);
1269 		BPF_ANCILLARY(VLAN_TAG_PRESENT);
1270 		BPF_ANCILLARY(PAY_OFFSET);
1271 		BPF_ANCILLARY(RANDOM);
1272 		BPF_ANCILLARY(VLAN_TPID);
1273 		}
1274 		fallthrough;
1275 	default:
1276 		return ftest->code;
1277 	}
1278 }
1279 
1280 void *bpf_internal_load_pointer_neg_helper(const struct sk_buff *skb,
1281 					   int k, unsigned int size);
1282 
1283 static inline int bpf_tell_extensions(void)
1284 {
1285 	return SKF_AD_MAX;
1286 }
1287 
1288 struct bpf_sock_addr_kern {
1289 	struct sock *sk;
1290 	struct sockaddr *uaddr;
1291 	/* Temporary "register" to make indirect stores to nested structures
1292 	 * defined above. We need three registers to make such a store, but
1293 	 * only two (src and dst) are available at convert_ctx_access time
1294 	 */
1295 	u64 tmp_reg;
1296 	void *t_ctx;	/* Attach type specific context. */
1297 };
1298 
1299 struct bpf_sock_ops_kern {
1300 	struct	sock *sk;
1301 	union {
1302 		u32 args[4];
1303 		u32 reply;
1304 		u32 replylong[4];
1305 	};
1306 	struct sk_buff	*syn_skb;
1307 	struct sk_buff	*skb;
1308 	void	*skb_data_end;
1309 	u8	op;
1310 	u8	is_fullsock;
1311 	u8	remaining_opt_len;
1312 	u64	temp;			/* temp and everything after is not
1313 					 * initialized to 0 before calling
1314 					 * the BPF program. New fields that
1315 					 * should be initialized to 0 should
1316 					 * be inserted before temp.
1317 					 * temp is scratch storage used by
1318 					 * sock_ops_convert_ctx_access
1319 					 * as temporary storage of a register.
1320 					 */
1321 };
1322 
1323 struct bpf_sysctl_kern {
1324 	struct ctl_table_header *head;
1325 	struct ctl_table *table;
1326 	void *cur_val;
1327 	size_t cur_len;
1328 	void *new_val;
1329 	size_t new_len;
1330 	int new_updated;
1331 	int write;
1332 	loff_t *ppos;
1333 	/* Temporary "register" for indirect stores to ppos. */
1334 	u64 tmp_reg;
1335 };
1336 
1337 #define BPF_SOCKOPT_KERN_BUF_SIZE	32
1338 struct bpf_sockopt_buf {
1339 	u8		data[BPF_SOCKOPT_KERN_BUF_SIZE];
1340 };
1341 
1342 struct bpf_sockopt_kern {
1343 	struct sock	*sk;
1344 	u8		*optval;
1345 	u8		*optval_end;
1346 	s32		level;
1347 	s32		optname;
1348 	s32		optlen;
1349 	/* for retval in struct bpf_cg_run_ctx */
1350 	struct task_struct *current_task;
1351 	/* Temporary "register" for indirect stores to ppos. */
1352 	u64		tmp_reg;
1353 };
1354 
1355 int copy_bpf_fprog_from_user(struct sock_fprog *dst, sockptr_t src, int len);
1356 
1357 struct bpf_sk_lookup_kern {
1358 	u16		family;
1359 	u16		protocol;
1360 	__be16		sport;
1361 	u16		dport;
1362 	struct {
1363 		__be32 saddr;
1364 		__be32 daddr;
1365 	} v4;
1366 	struct {
1367 		const struct in6_addr *saddr;
1368 		const struct in6_addr *daddr;
1369 	} v6;
1370 	struct sock	*selected_sk;
1371 	u32		ingress_ifindex;
1372 	bool		no_reuseport;
1373 };
1374 
1375 extern struct static_key_false bpf_sk_lookup_enabled;
1376 
1377 /* Runners for BPF_SK_LOOKUP programs to invoke on socket lookup.
1378  *
1379  * Allowed return values for a BPF SK_LOOKUP program are SK_PASS and
1380  * SK_DROP. Their meaning is as follows:
1381  *
1382  *  SK_PASS && ctx.selected_sk != NULL: use selected_sk as lookup result
1383  *  SK_PASS && ctx.selected_sk == NULL: continue to htable-based socket lookup
1384  *  SK_DROP                           : terminate lookup with -ECONNREFUSED
1385  *
1386  * This macro aggregates return values and selected sockets from
1387  * multiple BPF programs according to following rules in order:
1388  *
1389  *  1. If any program returned SK_PASS and a non-NULL ctx.selected_sk,
1390  *     macro result is SK_PASS and last ctx.selected_sk is used.
1391  *  2. If any program returned SK_DROP return value,
1392  *     macro result is SK_DROP.
1393  *  3. Otherwise result is SK_PASS and ctx.selected_sk is NULL.
1394  *
1395  * Caller must ensure that the prog array is non-NULL, and that the
1396  * array as well as the programs it contains remain valid.
1397  */
1398 #define BPF_PROG_SK_LOOKUP_RUN_ARRAY(array, ctx, func)			\
1399 	({								\
1400 		struct bpf_sk_lookup_kern *_ctx = &(ctx);		\
1401 		struct bpf_prog_array_item *_item;			\
1402 		struct sock *_selected_sk = NULL;			\
1403 		bool _no_reuseport = false;				\
1404 		struct bpf_prog *_prog;					\
1405 		bool _all_pass = true;					\
1406 		u32 _ret;						\
1407 									\
1408 		migrate_disable();					\
1409 		_item = &(array)->items[0];				\
1410 		while ((_prog = READ_ONCE(_item->prog))) {		\
1411 			/* restore most recent selection */		\
1412 			_ctx->selected_sk = _selected_sk;		\
1413 			_ctx->no_reuseport = _no_reuseport;		\
1414 									\
1415 			_ret = func(_prog, _ctx);			\
1416 			if (_ret == SK_PASS && _ctx->selected_sk) {	\
1417 				/* remember last non-NULL socket */	\
1418 				_selected_sk = _ctx->selected_sk;	\
1419 				_no_reuseport = _ctx->no_reuseport;	\
1420 			} else if (_ret == SK_DROP && _all_pass) {	\
1421 				_all_pass = false;			\
1422 			}						\
1423 			_item++;					\
1424 		}							\
1425 		_ctx->selected_sk = _selected_sk;			\
1426 		_ctx->no_reuseport = _no_reuseport;			\
1427 		migrate_enable();					\
1428 		_all_pass || _selected_sk ? SK_PASS : SK_DROP;		\
1429 	 })
1430 
1431 static inline bool bpf_sk_lookup_run_v4(struct net *net, int protocol,
1432 					const __be32 saddr, const __be16 sport,
1433 					const __be32 daddr, const u16 dport,
1434 					const int ifindex, struct sock **psk)
1435 {
1436 	struct bpf_prog_array *run_array;
1437 	struct sock *selected_sk = NULL;
1438 	bool no_reuseport = false;
1439 
1440 	rcu_read_lock();
1441 	run_array = rcu_dereference(net->bpf.run_array[NETNS_BPF_SK_LOOKUP]);
1442 	if (run_array) {
1443 		struct bpf_sk_lookup_kern ctx = {
1444 			.family		= AF_INET,
1445 			.protocol	= protocol,
1446 			.v4.saddr	= saddr,
1447 			.v4.daddr	= daddr,
1448 			.sport		= sport,
1449 			.dport		= dport,
1450 			.ingress_ifindex	= ifindex,
1451 		};
1452 		u32 act;
1453 
1454 		act = BPF_PROG_SK_LOOKUP_RUN_ARRAY(run_array, ctx, bpf_prog_run);
1455 		if (act == SK_PASS) {
1456 			selected_sk = ctx.selected_sk;
1457 			no_reuseport = ctx.no_reuseport;
1458 		} else {
1459 			selected_sk = ERR_PTR(-ECONNREFUSED);
1460 		}
1461 	}
1462 	rcu_read_unlock();
1463 	*psk = selected_sk;
1464 	return no_reuseport;
1465 }
1466 
1467 #if IS_ENABLED(CONFIG_IPV6)
1468 static inline bool bpf_sk_lookup_run_v6(struct net *net, int protocol,
1469 					const struct in6_addr *saddr,
1470 					const __be16 sport,
1471 					const struct in6_addr *daddr,
1472 					const u16 dport,
1473 					const int ifindex, struct sock **psk)
1474 {
1475 	struct bpf_prog_array *run_array;
1476 	struct sock *selected_sk = NULL;
1477 	bool no_reuseport = false;
1478 
1479 	rcu_read_lock();
1480 	run_array = rcu_dereference(net->bpf.run_array[NETNS_BPF_SK_LOOKUP]);
1481 	if (run_array) {
1482 		struct bpf_sk_lookup_kern ctx = {
1483 			.family		= AF_INET6,
1484 			.protocol	= protocol,
1485 			.v6.saddr	= saddr,
1486 			.v6.daddr	= daddr,
1487 			.sport		= sport,
1488 			.dport		= dport,
1489 			.ingress_ifindex	= ifindex,
1490 		};
1491 		u32 act;
1492 
1493 		act = BPF_PROG_SK_LOOKUP_RUN_ARRAY(run_array, ctx, bpf_prog_run);
1494 		if (act == SK_PASS) {
1495 			selected_sk = ctx.selected_sk;
1496 			no_reuseport = ctx.no_reuseport;
1497 		} else {
1498 			selected_sk = ERR_PTR(-ECONNREFUSED);
1499 		}
1500 	}
1501 	rcu_read_unlock();
1502 	*psk = selected_sk;
1503 	return no_reuseport;
1504 }
1505 #endif /* IS_ENABLED(CONFIG_IPV6) */
1506 
1507 static __always_inline long __bpf_xdp_redirect_map(struct bpf_map *map, u64 index,
1508 						   u64 flags, const u64 flag_mask,
1509 						   void *lookup_elem(struct bpf_map *map, u32 key))
1510 {
1511 	struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
1512 	const u64 action_mask = XDP_ABORTED | XDP_DROP | XDP_PASS | XDP_TX;
1513 
1514 	/* Lower bits of the flags are used as return code on lookup failure */
1515 	if (unlikely(flags & ~(action_mask | flag_mask)))
1516 		return XDP_ABORTED;
1517 
1518 	ri->tgt_value = lookup_elem(map, index);
1519 	if (unlikely(!ri->tgt_value) && !(flags & BPF_F_BROADCAST)) {
1520 		/* If the lookup fails we want to clear out the state in the
1521 		 * redirect_info struct completely, so that if an eBPF program
1522 		 * performs multiple lookups, the last one always takes
1523 		 * precedence.
1524 		 */
1525 		ri->map_id = INT_MAX; /* Valid map id idr range: [1,INT_MAX[ */
1526 		ri->map_type = BPF_MAP_TYPE_UNSPEC;
1527 		return flags & action_mask;
1528 	}
1529 
1530 	ri->tgt_index = index;
1531 	ri->map_id = map->id;
1532 	ri->map_type = map->map_type;
1533 
1534 	if (flags & BPF_F_BROADCAST) {
1535 		WRITE_ONCE(ri->map, map);
1536 		ri->flags = flags;
1537 	} else {
1538 		WRITE_ONCE(ri->map, NULL);
1539 		ri->flags = 0;
1540 	}
1541 
1542 	return XDP_REDIRECT;
1543 }
1544 
1545 #ifdef CONFIG_NET
1546 int __bpf_skb_load_bytes(const struct sk_buff *skb, u32 offset, void *to, u32 len);
1547 int __bpf_skb_store_bytes(struct sk_buff *skb, u32 offset, const void *from,
1548 			  u32 len, u64 flags);
1549 int __bpf_xdp_load_bytes(struct xdp_buff *xdp, u32 offset, void *buf, u32 len);
1550 int __bpf_xdp_store_bytes(struct xdp_buff *xdp, u32 offset, void *buf, u32 len);
1551 void *bpf_xdp_pointer(struct xdp_buff *xdp, u32 offset, u32 len);
1552 void bpf_xdp_copy_buf(struct xdp_buff *xdp, unsigned long off,
1553 		      void *buf, unsigned long len, bool flush);
1554 #else /* CONFIG_NET */
1555 static inline int __bpf_skb_load_bytes(const struct sk_buff *skb, u32 offset,
1556 				       void *to, u32 len)
1557 {
1558 	return -EOPNOTSUPP;
1559 }
1560 
1561 static inline int __bpf_skb_store_bytes(struct sk_buff *skb, u32 offset,
1562 					const void *from, u32 len, u64 flags)
1563 {
1564 	return -EOPNOTSUPP;
1565 }
1566 
1567 static inline int __bpf_xdp_load_bytes(struct xdp_buff *xdp, u32 offset,
1568 				       void *buf, u32 len)
1569 {
1570 	return -EOPNOTSUPP;
1571 }
1572 
1573 static inline int __bpf_xdp_store_bytes(struct xdp_buff *xdp, u32 offset,
1574 					void *buf, u32 len)
1575 {
1576 	return -EOPNOTSUPP;
1577 }
1578 
1579 static inline void *bpf_xdp_pointer(struct xdp_buff *xdp, u32 offset, u32 len)
1580 {
1581 	return NULL;
1582 }
1583 
1584 static inline void *bpf_xdp_copy_buf(struct xdp_buff *xdp, unsigned long off, void *buf,
1585 				     unsigned long len, bool flush)
1586 {
1587 	return NULL;
1588 }
1589 #endif /* CONFIG_NET */
1590 
1591 #endif /* __LINUX_FILTER_H__ */
1592