xref: /linux/include/linux/filter.h (revision ec2e0fb07d789976c601bec19ecced7a501c3705)
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 special ldsx instruction. Same as BPF_IND */
73 #define BPF_PROBE_MEMSX	0x40
74 
75 /* unused opcode to mark special load instruction. Same as BPF_MSH */
76 #define BPF_PROBE_MEM32	0xa0
77 
78 /* unused opcode to mark special atomic instruction */
79 #define BPF_PROBE_ATOMIC 0xe0
80 
81 /* unused opcode to mark special ldsx instruction. Same as BPF_NOSPEC */
82 #define BPF_PROBE_MEM32SX 0xc0
83 
84 /* unused opcode to mark call to interpreter with arguments */
85 #define BPF_CALL_ARGS	0xe0
86 
87 /* unused opcode to mark speculation barrier for mitigating
88  * Spectre v1 and v4
89  */
90 #define BPF_NOSPEC	0xc0
91 
92 /* As per nm, we expose JITed images as text (code) section for
93  * kallsyms. That way, tools like perf can find it to match
94  * addresses.
95  */
96 #define BPF_SYM_ELF_TYPE	't'
97 
98 /* BPF program can access up to 512 bytes of stack space. */
99 #define MAX_BPF_STACK	512
100 
101 /* Helper macros for filter block array initializers. */
102 
103 /* ALU ops on registers, bpf_add|sub|...: dst_reg += src_reg */
104 
105 #define BPF_ALU64_REG_OFF(OP, DST, SRC, OFF)			\
106 	((struct bpf_insn) {					\
107 		.code  = BPF_ALU64 | BPF_OP(OP) | BPF_X,	\
108 		.dst_reg = DST,					\
109 		.src_reg = SRC,					\
110 		.off   = OFF,					\
111 		.imm   = 0 })
112 
113 #define BPF_ALU64_REG(OP, DST, SRC)				\
114 	BPF_ALU64_REG_OFF(OP, DST, SRC, 0)
115 
116 #define BPF_ALU32_REG_OFF(OP, DST, SRC, OFF)			\
117 	((struct bpf_insn) {					\
118 		.code  = BPF_ALU | BPF_OP(OP) | BPF_X,		\
119 		.dst_reg = DST,					\
120 		.src_reg = SRC,					\
121 		.off   = OFF,					\
122 		.imm   = 0 })
123 
124 #define BPF_ALU32_REG(OP, DST, SRC)				\
125 	BPF_ALU32_REG_OFF(OP, DST, SRC, 0)
126 
127 /* ALU ops on immediates, bpf_add|sub|...: dst_reg += imm32 */
128 
129 #define BPF_ALU64_IMM_OFF(OP, DST, IMM, OFF)			\
130 	((struct bpf_insn) {					\
131 		.code  = BPF_ALU64 | BPF_OP(OP) | BPF_K,	\
132 		.dst_reg = DST,					\
133 		.src_reg = 0,					\
134 		.off   = OFF,					\
135 		.imm   = IMM })
136 #define BPF_ALU64_IMM(OP, DST, IMM)				\
137 	BPF_ALU64_IMM_OFF(OP, DST, IMM, 0)
138 
139 #define BPF_ALU32_IMM_OFF(OP, DST, IMM, OFF)			\
140 	((struct bpf_insn) {					\
141 		.code  = BPF_ALU | BPF_OP(OP) | BPF_K,		\
142 		.dst_reg = DST,					\
143 		.src_reg = 0,					\
144 		.off   = OFF,					\
145 		.imm   = IMM })
146 #define BPF_ALU32_IMM(OP, DST, IMM)				\
147 	BPF_ALU32_IMM_OFF(OP, DST, IMM, 0)
148 
149 /* Endianess conversion, cpu_to_{l,b}e(), {l,b}e_to_cpu() */
150 
151 #define BPF_ENDIAN(TYPE, DST, LEN)				\
152 	((struct bpf_insn) {					\
153 		.code  = BPF_ALU | BPF_END | BPF_SRC(TYPE),	\
154 		.dst_reg = DST,					\
155 		.src_reg = 0,					\
156 		.off   = 0,					\
157 		.imm   = LEN })
158 
159 /* Byte Swap, bswap16/32/64 */
160 
161 #define BPF_BSWAP(DST, LEN)					\
162 	((struct bpf_insn) {					\
163 		.code  = BPF_ALU64 | BPF_END | BPF_SRC(BPF_TO_LE),	\
164 		.dst_reg = DST,					\
165 		.src_reg = 0,					\
166 		.off   = 0,					\
167 		.imm   = LEN })
168 
169 /* Short form of mov, dst_reg = src_reg */
170 
171 #define BPF_MOV64_REG(DST, SRC)					\
172 	((struct bpf_insn) {					\
173 		.code  = BPF_ALU64 | BPF_MOV | BPF_X,		\
174 		.dst_reg = DST,					\
175 		.src_reg = SRC,					\
176 		.off   = 0,					\
177 		.imm   = 0 })
178 
179 #define BPF_MOV32_REG(DST, SRC)					\
180 	((struct bpf_insn) {					\
181 		.code  = BPF_ALU | BPF_MOV | BPF_X,		\
182 		.dst_reg = DST,					\
183 		.src_reg = SRC,					\
184 		.off   = 0,					\
185 		.imm   = 0 })
186 
187 /* Special (internal-only) form of mov, used to resolve per-CPU addrs:
188  * dst_reg = src_reg + <percpu_base_off>
189  * BPF_ADDR_PERCPU is used as a special insn->off value.
190  */
191 #define BPF_ADDR_PERCPU	(-1)
192 
193 #define BPF_MOV64_PERCPU_REG(DST, SRC)				\
194 	((struct bpf_insn) {					\
195 		.code  = BPF_ALU64 | BPF_MOV | BPF_X,		\
196 		.dst_reg = DST,					\
197 		.src_reg = SRC,					\
198 		.off   = BPF_ADDR_PERCPU,			\
199 		.imm   = 0 })
200 
insn_is_mov_percpu_addr(const struct bpf_insn * insn)201 static inline bool insn_is_mov_percpu_addr(const struct bpf_insn *insn)
202 {
203 	return insn->code == (BPF_ALU64 | BPF_MOV | BPF_X) && insn->off == BPF_ADDR_PERCPU;
204 }
205 
206 /* Short form of mov, dst_reg = imm32 */
207 
208 #define BPF_MOV64_IMM(DST, IMM)					\
209 	((struct bpf_insn) {					\
210 		.code  = BPF_ALU64 | BPF_MOV | BPF_K,		\
211 		.dst_reg = DST,					\
212 		.src_reg = 0,					\
213 		.off   = 0,					\
214 		.imm   = IMM })
215 
216 #define BPF_MOV32_IMM(DST, IMM)					\
217 	((struct bpf_insn) {					\
218 		.code  = BPF_ALU | BPF_MOV | BPF_K,		\
219 		.dst_reg = DST,					\
220 		.src_reg = 0,					\
221 		.off   = 0,					\
222 		.imm   = IMM })
223 
224 /* Short form of movsx, dst_reg = (s8,s16,s32)src_reg */
225 
226 #define BPF_MOVSX64_REG(DST, SRC, OFF)				\
227 	((struct bpf_insn) {					\
228 		.code  = BPF_ALU64 | BPF_MOV | BPF_X,		\
229 		.dst_reg = DST,					\
230 		.src_reg = SRC,					\
231 		.off   = OFF,					\
232 		.imm   = 0 })
233 
234 #define BPF_MOVSX32_REG(DST, SRC, OFF)				\
235 	((struct bpf_insn) {					\
236 		.code  = BPF_ALU | BPF_MOV | BPF_X,		\
237 		.dst_reg = DST,					\
238 		.src_reg = SRC,					\
239 		.off   = OFF,					\
240 		.imm   = 0 })
241 
242 /* Special form of mov32, used for doing explicit zero extension on dst. */
243 #define BPF_ZEXT_REG(DST)					\
244 	((struct bpf_insn) {					\
245 		.code  = BPF_ALU | BPF_MOV | BPF_X,		\
246 		.dst_reg = DST,					\
247 		.src_reg = DST,					\
248 		.off   = 0,					\
249 		.imm   = 1 })
250 
insn_is_zext(const struct bpf_insn * insn)251 static inline bool insn_is_zext(const struct bpf_insn *insn)
252 {
253 	return insn->code == (BPF_ALU | BPF_MOV | BPF_X) && insn->imm == 1;
254 }
255 
256 /* addr_space_cast from as(0) to as(1) is for converting bpf arena pointers
257  * to pointers in user vma.
258  */
insn_is_cast_user(const struct bpf_insn * insn)259 static inline bool insn_is_cast_user(const struct bpf_insn *insn)
260 {
261 	return insn->code == (BPF_ALU64 | BPF_MOV | BPF_X) &&
262 			      insn->off == BPF_ADDR_SPACE_CAST &&
263 			      insn->imm == 1U << 16;
264 }
265 
266 /* BPF_LD_IMM64 macro encodes single 'load 64-bit immediate' insn */
267 #define BPF_LD_IMM64(DST, IMM)					\
268 	BPF_LD_IMM64_RAW(DST, 0, IMM)
269 
270 #define BPF_LD_IMM64_RAW(DST, SRC, IMM)				\
271 	((struct bpf_insn) {					\
272 		.code  = BPF_LD | BPF_DW | BPF_IMM,		\
273 		.dst_reg = DST,					\
274 		.src_reg = SRC,					\
275 		.off   = 0,					\
276 		.imm   = (__u32) (IMM) }),			\
277 	((struct bpf_insn) {					\
278 		.code  = 0, /* zero is reserved opcode */	\
279 		.dst_reg = 0,					\
280 		.src_reg = 0,					\
281 		.off   = 0,					\
282 		.imm   = ((__u64) (IMM)) >> 32 })
283 
284 /* pseudo BPF_LD_IMM64 insn used to refer to process-local map_fd */
285 #define BPF_LD_MAP_FD(DST, MAP_FD)				\
286 	BPF_LD_IMM64_RAW(DST, BPF_PSEUDO_MAP_FD, MAP_FD)
287 
288 /* Short form of mov based on type, BPF_X: dst_reg = src_reg, BPF_K: dst_reg = imm32 */
289 
290 #define BPF_MOV64_RAW(TYPE, DST, SRC, IMM)			\
291 	((struct bpf_insn) {					\
292 		.code  = BPF_ALU64 | BPF_MOV | BPF_SRC(TYPE),	\
293 		.dst_reg = DST,					\
294 		.src_reg = SRC,					\
295 		.off   = 0,					\
296 		.imm   = IMM })
297 
298 #define BPF_MOV32_RAW(TYPE, DST, SRC, IMM)			\
299 	((struct bpf_insn) {					\
300 		.code  = BPF_ALU | BPF_MOV | BPF_SRC(TYPE),	\
301 		.dst_reg = DST,					\
302 		.src_reg = SRC,					\
303 		.off   = 0,					\
304 		.imm   = IMM })
305 
306 /* Direct packet access, R0 = *(uint *) (skb->data + imm32) */
307 
308 #define BPF_LD_ABS(SIZE, IMM)					\
309 	((struct bpf_insn) {					\
310 		.code  = BPF_LD | BPF_SIZE(SIZE) | BPF_ABS,	\
311 		.dst_reg = 0,					\
312 		.src_reg = 0,					\
313 		.off   = 0,					\
314 		.imm   = IMM })
315 
316 /* Indirect packet access, R0 = *(uint *) (skb->data + src_reg + imm32) */
317 
318 #define BPF_LD_IND(SIZE, SRC, IMM)				\
319 	((struct bpf_insn) {					\
320 		.code  = BPF_LD | BPF_SIZE(SIZE) | BPF_IND,	\
321 		.dst_reg = 0,					\
322 		.src_reg = SRC,					\
323 		.off   = 0,					\
324 		.imm   = IMM })
325 
326 /* Memory load, dst_reg = *(uint *) (src_reg + off16) */
327 
328 #define BPF_LDX_MEM(SIZE, DST, SRC, OFF)			\
329 	((struct bpf_insn) {					\
330 		.code  = BPF_LDX | BPF_SIZE(SIZE) | BPF_MEM,	\
331 		.dst_reg = DST,					\
332 		.src_reg = SRC,					\
333 		.off   = OFF,					\
334 		.imm   = 0 })
335 
336 /* Memory load, dst_reg = *(signed size *) (src_reg + off16) */
337 
338 #define BPF_LDX_MEMSX(SIZE, DST, SRC, OFF)			\
339 	((struct bpf_insn) {					\
340 		.code  = BPF_LDX | BPF_SIZE(SIZE) | BPF_MEMSX,	\
341 		.dst_reg = DST,					\
342 		.src_reg = SRC,					\
343 		.off   = OFF,					\
344 		.imm   = 0 })
345 
346 /* Memory store, *(uint *) (dst_reg + off16) = src_reg */
347 
348 #define BPF_STX_MEM(SIZE, DST, SRC, OFF)			\
349 	((struct bpf_insn) {					\
350 		.code  = BPF_STX | BPF_SIZE(SIZE) | BPF_MEM,	\
351 		.dst_reg = DST,					\
352 		.src_reg = SRC,					\
353 		.off   = OFF,					\
354 		.imm   = 0 })
355 
356 
357 /*
358  * Atomic operations:
359  *
360  *   BPF_ADD                  *(uint *) (dst_reg + off16) += src_reg
361  *   BPF_AND                  *(uint *) (dst_reg + off16) &= src_reg
362  *   BPF_OR                   *(uint *) (dst_reg + off16) |= src_reg
363  *   BPF_XOR                  *(uint *) (dst_reg + off16) ^= src_reg
364  *   BPF_ADD | BPF_FETCH      src_reg = atomic_fetch_add(dst_reg + off16, src_reg);
365  *   BPF_AND | BPF_FETCH      src_reg = atomic_fetch_and(dst_reg + off16, src_reg);
366  *   BPF_OR | BPF_FETCH       src_reg = atomic_fetch_or(dst_reg + off16, src_reg);
367  *   BPF_XOR | BPF_FETCH      src_reg = atomic_fetch_xor(dst_reg + off16, src_reg);
368  *   BPF_XCHG                 src_reg = atomic_xchg(dst_reg + off16, src_reg)
369  *   BPF_CMPXCHG              r0 = atomic_cmpxchg(dst_reg + off16, r0, src_reg)
370  *   BPF_LOAD_ACQ             dst_reg = smp_load_acquire(src_reg + off16)
371  *   BPF_STORE_REL            smp_store_release(dst_reg + off16, src_reg)
372  */
373 
374 #define BPF_ATOMIC_OP(SIZE, OP, DST, SRC, OFF)			\
375 	((struct bpf_insn) {					\
376 		.code  = BPF_STX | BPF_SIZE(SIZE) | BPF_ATOMIC,	\
377 		.dst_reg = DST,					\
378 		.src_reg = SRC,					\
379 		.off   = OFF,					\
380 		.imm   = OP })
381 
382 /* Legacy alias */
383 #define BPF_STX_XADD(SIZE, DST, SRC, OFF) BPF_ATOMIC_OP(SIZE, BPF_ADD, DST, SRC, OFF)
384 
385 /* Memory store, *(uint *) (dst_reg + off16) = imm32 */
386 
387 #define BPF_ST_MEM(SIZE, DST, OFF, IMM)				\
388 	((struct bpf_insn) {					\
389 		.code  = BPF_ST | BPF_SIZE(SIZE) | BPF_MEM,	\
390 		.dst_reg = DST,					\
391 		.src_reg = 0,					\
392 		.off   = OFF,					\
393 		.imm   = IMM })
394 
395 /* Conditional jumps against registers, if (dst_reg 'op' src_reg) goto pc + off16 */
396 
397 #define BPF_JMP_REG(OP, DST, SRC, OFF)				\
398 	((struct bpf_insn) {					\
399 		.code  = BPF_JMP | BPF_OP(OP) | BPF_X,		\
400 		.dst_reg = DST,					\
401 		.src_reg = SRC,					\
402 		.off   = OFF,					\
403 		.imm   = 0 })
404 
405 /* Conditional jumps against immediates, if (dst_reg 'op' imm32) goto pc + off16 */
406 
407 #define BPF_JMP_IMM(OP, DST, IMM, OFF)				\
408 	((struct bpf_insn) {					\
409 		.code  = BPF_JMP | BPF_OP(OP) | BPF_K,		\
410 		.dst_reg = DST,					\
411 		.src_reg = 0,					\
412 		.off   = OFF,					\
413 		.imm   = IMM })
414 
415 /* Like BPF_JMP_REG, but with 32-bit wide operands for comparison. */
416 
417 #define BPF_JMP32_REG(OP, DST, SRC, OFF)			\
418 	((struct bpf_insn) {					\
419 		.code  = BPF_JMP32 | BPF_OP(OP) | BPF_X,	\
420 		.dst_reg = DST,					\
421 		.src_reg = SRC,					\
422 		.off   = OFF,					\
423 		.imm   = 0 })
424 
425 /* Like BPF_JMP_IMM, but with 32-bit wide operands for comparison. */
426 
427 #define BPF_JMP32_IMM(OP, DST, IMM, OFF)			\
428 	((struct bpf_insn) {					\
429 		.code  = BPF_JMP32 | BPF_OP(OP) | BPF_K,	\
430 		.dst_reg = DST,					\
431 		.src_reg = 0,					\
432 		.off   = OFF,					\
433 		.imm   = IMM })
434 
435 /* Unconditional jumps, goto pc + off16 */
436 
437 #define BPF_JMP_A(OFF)						\
438 	((struct bpf_insn) {					\
439 		.code  = BPF_JMP | BPF_JA,			\
440 		.dst_reg = 0,					\
441 		.src_reg = 0,					\
442 		.off   = OFF,					\
443 		.imm   = 0 })
444 
445 /* Unconditional jumps, gotol pc + imm32 */
446 
447 #define BPF_JMP32_A(IMM)					\
448 	((struct bpf_insn) {					\
449 		.code  = BPF_JMP32 | BPF_JA,			\
450 		.dst_reg = 0,					\
451 		.src_reg = 0,					\
452 		.off   = 0,					\
453 		.imm   = IMM })
454 
455 /* Relative call */
456 
457 #define BPF_CALL_REL(TGT)					\
458 	((struct bpf_insn) {					\
459 		.code  = BPF_JMP | BPF_CALL,			\
460 		.dst_reg = 0,					\
461 		.src_reg = BPF_PSEUDO_CALL,			\
462 		.off   = 0,					\
463 		.imm   = TGT })
464 
465 /* Convert function address to BPF immediate */
466 
467 #define BPF_CALL_IMM(x)	((void *)(x) - (void *)__bpf_call_base)
468 
469 #define BPF_EMIT_CALL(FUNC)					\
470 	((struct bpf_insn) {					\
471 		.code  = BPF_JMP | BPF_CALL,			\
472 		.dst_reg = 0,					\
473 		.src_reg = 0,					\
474 		.off   = 0,					\
475 		.imm   = BPF_CALL_IMM(FUNC) })
476 
477 /* Kfunc call */
478 
479 #define BPF_CALL_KFUNC(OFF, IMM)				\
480 	((struct bpf_insn) {					\
481 		.code  = BPF_JMP | BPF_CALL,			\
482 		.dst_reg = 0,					\
483 		.src_reg = BPF_PSEUDO_KFUNC_CALL,		\
484 		.off   = OFF,					\
485 		.imm   = IMM })
486 
487 /* Raw code statement block */
488 
489 #define BPF_RAW_INSN(CODE, DST, SRC, OFF, IMM)			\
490 	((struct bpf_insn) {					\
491 		.code  = CODE,					\
492 		.dst_reg = DST,					\
493 		.src_reg = SRC,					\
494 		.off   = OFF,					\
495 		.imm   = IMM })
496 
497 /* Program exit */
498 
499 #define BPF_EXIT_INSN()						\
500 	((struct bpf_insn) {					\
501 		.code  = BPF_JMP | BPF_EXIT,			\
502 		.dst_reg = 0,					\
503 		.src_reg = 0,					\
504 		.off   = 0,					\
505 		.imm   = 0 })
506 
507 /* Speculation barrier */
508 
509 #define BPF_ST_NOSPEC()						\
510 	((struct bpf_insn) {					\
511 		.code  = BPF_ST | BPF_NOSPEC,			\
512 		.dst_reg = 0,					\
513 		.src_reg = 0,					\
514 		.off   = 0,					\
515 		.imm   = 0 })
516 
517 /* Internal classic blocks for direct assignment */
518 
519 #define __BPF_STMT(CODE, K)					\
520 	((struct sock_filter) BPF_STMT(CODE, K))
521 
522 #define __BPF_JUMP(CODE, K, JT, JF)				\
523 	((struct sock_filter) BPF_JUMP(CODE, K, JT, JF))
524 
525 #define bytes_to_bpf_size(bytes)				\
526 ({								\
527 	int bpf_size = -EINVAL;					\
528 								\
529 	if (bytes == sizeof(u8))				\
530 		bpf_size = BPF_B;				\
531 	else if (bytes == sizeof(u16))				\
532 		bpf_size = BPF_H;				\
533 	else if (bytes == sizeof(u32))				\
534 		bpf_size = BPF_W;				\
535 	else if (bytes == sizeof(u64))				\
536 		bpf_size = BPF_DW;				\
537 								\
538 	bpf_size;						\
539 })
540 
541 #define bpf_size_to_bytes(bpf_size)				\
542 ({								\
543 	int bytes = -EINVAL;					\
544 								\
545 	if (bpf_size == BPF_B)					\
546 		bytes = sizeof(u8);				\
547 	else if (bpf_size == BPF_H)				\
548 		bytes = sizeof(u16);				\
549 	else if (bpf_size == BPF_W)				\
550 		bytes = sizeof(u32);				\
551 	else if (bpf_size == BPF_DW)				\
552 		bytes = sizeof(u64);				\
553 								\
554 	bytes;							\
555 })
556 
557 #define BPF_SIZEOF(type)					\
558 	({							\
559 		const int __size = bytes_to_bpf_size(sizeof(type)); \
560 		BUILD_BUG_ON(__size < 0);			\
561 		__size;						\
562 	})
563 
564 #define BPF_FIELD_SIZEOF(type, field)				\
565 	({							\
566 		const int __size = bytes_to_bpf_size(sizeof_field(type, field)); \
567 		BUILD_BUG_ON(__size < 0);			\
568 		__size;						\
569 	})
570 
571 #define BPF_LDST_BYTES(insn)					\
572 	({							\
573 		const int __size = bpf_size_to_bytes(BPF_SIZE((insn)->code)); \
574 		WARN_ON(__size < 0);				\
575 		__size;						\
576 	})
577 
578 #define __BPF_MAP_0(m, v, ...) v
579 #define __BPF_MAP_1(m, v, t, a, ...) m(t, a)
580 #define __BPF_MAP_2(m, v, t, a, ...) m(t, a), __BPF_MAP_1(m, v, __VA_ARGS__)
581 #define __BPF_MAP_3(m, v, t, a, ...) m(t, a), __BPF_MAP_2(m, v, __VA_ARGS__)
582 #define __BPF_MAP_4(m, v, t, a, ...) m(t, a), __BPF_MAP_3(m, v, __VA_ARGS__)
583 #define __BPF_MAP_5(m, v, t, a, ...) m(t, a), __BPF_MAP_4(m, v, __VA_ARGS__)
584 
585 #define __BPF_REG_0(...) __BPF_PAD(5)
586 #define __BPF_REG_1(...) __BPF_MAP(1, __VA_ARGS__), __BPF_PAD(4)
587 #define __BPF_REG_2(...) __BPF_MAP(2, __VA_ARGS__), __BPF_PAD(3)
588 #define __BPF_REG_3(...) __BPF_MAP(3, __VA_ARGS__), __BPF_PAD(2)
589 #define __BPF_REG_4(...) __BPF_MAP(4, __VA_ARGS__), __BPF_PAD(1)
590 #define __BPF_REG_5(...) __BPF_MAP(5, __VA_ARGS__)
591 
592 #define __BPF_MAP(n, ...) __BPF_MAP_##n(__VA_ARGS__)
593 #define __BPF_REG(n, ...) __BPF_REG_##n(__VA_ARGS__)
594 
595 #define __BPF_CAST(t, a)						       \
596 	(__force t)							       \
597 	(__force							       \
598 	 typeof(__builtin_choose_expr(sizeof(t) == sizeof(unsigned long),      \
599 				      (unsigned long)0, (t)0))) a
600 #define __BPF_V void
601 #define __BPF_N
602 
603 #define __BPF_DECL_ARGS(t, a) t   a
604 #define __BPF_DECL_REGS(t, a) u64 a
605 
606 #define __BPF_PAD(n)							       \
607 	__BPF_MAP(n, __BPF_DECL_ARGS, __BPF_N, u64, __ur_1, u64, __ur_2,       \
608 		  u64, __ur_3, u64, __ur_4, u64, __ur_5)
609 
610 #define BPF_CALL_x(x, attr, name, ...)					       \
611 	static __always_inline						       \
612 	u64 ____##name(__BPF_MAP(x, __BPF_DECL_ARGS, __BPF_V, __VA_ARGS__));   \
613 	typedef u64 (*btf_##name)(__BPF_MAP(x, __BPF_DECL_ARGS, __BPF_V, __VA_ARGS__)); \
614 	attr u64 name(__BPF_REG(x, __BPF_DECL_REGS, __BPF_N, __VA_ARGS__));    \
615 	attr u64 name(__BPF_REG(x, __BPF_DECL_REGS, __BPF_N, __VA_ARGS__))     \
616 	{								       \
617 		return ((btf_##name)____##name)(__BPF_MAP(x,__BPF_CAST,__BPF_N,__VA_ARGS__));\
618 	}								       \
619 	static __always_inline						       \
620 	u64 ____##name(__BPF_MAP(x, __BPF_DECL_ARGS, __BPF_V, __VA_ARGS__))
621 
622 #define __NOATTR
623 #define BPF_CALL_0(name, ...)	BPF_CALL_x(0, __NOATTR, name, __VA_ARGS__)
624 #define BPF_CALL_1(name, ...)	BPF_CALL_x(1, __NOATTR, name, __VA_ARGS__)
625 #define BPF_CALL_2(name, ...)	BPF_CALL_x(2, __NOATTR, name, __VA_ARGS__)
626 #define BPF_CALL_3(name, ...)	BPF_CALL_x(3, __NOATTR, name, __VA_ARGS__)
627 #define BPF_CALL_4(name, ...)	BPF_CALL_x(4, __NOATTR, name, __VA_ARGS__)
628 #define BPF_CALL_5(name, ...)	BPF_CALL_x(5, __NOATTR, name, __VA_ARGS__)
629 
630 #define NOTRACE_BPF_CALL_1(name, ...)	BPF_CALL_x(1, notrace, name, __VA_ARGS__)
631 
632 #define bpf_ctx_range(TYPE, MEMBER)						\
633 	offsetof(TYPE, MEMBER) ... offsetofend(TYPE, MEMBER) - 1
634 #define bpf_ctx_range_till(TYPE, MEMBER1, MEMBER2)				\
635 	offsetof(TYPE, MEMBER1) ... offsetofend(TYPE, MEMBER2) - 1
636 #if BITS_PER_LONG == 64
637 # define bpf_ctx_range_ptr(TYPE, MEMBER)					\
638 	offsetof(TYPE, MEMBER) ... offsetofend(TYPE, MEMBER) - 1
639 #else
640 # define bpf_ctx_range_ptr(TYPE, MEMBER)					\
641 	offsetof(TYPE, MEMBER) ... offsetof(TYPE, MEMBER) + 8 - 1
642 #endif /* BITS_PER_LONG == 64 */
643 
644 #define bpf_target_off(TYPE, MEMBER, SIZE, PTR_SIZE)				\
645 	({									\
646 		BUILD_BUG_ON(sizeof_field(TYPE, MEMBER) != (SIZE));		\
647 		*(PTR_SIZE) = (SIZE);						\
648 		offsetof(TYPE, MEMBER);						\
649 	})
650 
651 /* A struct sock_filter is architecture independent. */
652 struct compat_sock_fprog {
653 	u16		len;
654 	compat_uptr_t	filter;	/* struct sock_filter * */
655 };
656 
657 struct sock_fprog_kern {
658 	u16			len;
659 	struct sock_filter	*filter;
660 };
661 
662 /* Some arches need doubleword alignment for their instructions and/or data */
663 #define BPF_IMAGE_ALIGNMENT 8
664 
665 struct bpf_binary_header {
666 	u32 size;
667 	u8 image[] __aligned(BPF_IMAGE_ALIGNMENT);
668 };
669 
670 struct bpf_prog_stats {
671 	u64_stats_t cnt;
672 	u64_stats_t nsecs;
673 	u64_stats_t misses;
674 	struct u64_stats_sync syncp;
675 } __aligned(2 * sizeof(u64));
676 
677 struct bpf_timed_may_goto {
678 	u64 count;
679 	u64 timestamp;
680 };
681 
682 struct sk_filter {
683 	refcount_t	refcnt;
684 	struct rcu_head	rcu;
685 	struct bpf_prog	*prog;
686 };
687 
688 DECLARE_STATIC_KEY_FALSE(bpf_stats_enabled_key);
689 
690 extern struct mutex nf_conn_btf_access_lock;
691 extern int (*nfct_btf_struct_access)(struct bpf_verifier_log *log,
692 				     const struct bpf_reg_state *reg,
693 				     int off, int size);
694 
695 typedef unsigned int (*bpf_dispatcher_fn)(const void *ctx,
696 					  const struct bpf_insn *insnsi,
697 					  unsigned int (*bpf_func)(const void *,
698 								   const struct bpf_insn *));
699 
__bpf_prog_run(const struct bpf_prog * prog,const void * ctx,bpf_dispatcher_fn dfunc)700 static __always_inline u32 __bpf_prog_run(const struct bpf_prog *prog,
701 					  const void *ctx,
702 					  bpf_dispatcher_fn dfunc)
703 {
704 	u32 ret;
705 
706 	cant_migrate();
707 	if (static_branch_unlikely(&bpf_stats_enabled_key)) {
708 		struct bpf_prog_stats *stats;
709 		u64 duration, start = sched_clock();
710 		unsigned long flags;
711 
712 		ret = dfunc(ctx, prog->insnsi, prog->bpf_func);
713 
714 		duration = sched_clock() - start;
715 		stats = this_cpu_ptr(prog->stats);
716 		flags = u64_stats_update_begin_irqsave(&stats->syncp);
717 		u64_stats_inc(&stats->cnt);
718 		u64_stats_add(&stats->nsecs, duration);
719 		u64_stats_update_end_irqrestore(&stats->syncp, flags);
720 	} else {
721 		ret = dfunc(ctx, prog->insnsi, prog->bpf_func);
722 	}
723 	return ret;
724 }
725 
bpf_prog_run(const struct bpf_prog * prog,const void * ctx)726 static __always_inline u32 bpf_prog_run(const struct bpf_prog *prog, const void *ctx)
727 {
728 	return __bpf_prog_run(prog, ctx, bpf_dispatcher_nop_func);
729 }
730 
731 /*
732  * Use in preemptible and therefore migratable context to make sure that
733  * the execution of the BPF program runs on one CPU.
734  *
735  * This uses migrate_disable/enable() explicitly to document that the
736  * invocation of a BPF program does not require reentrancy protection
737  * against a BPF program which is invoked from a preempting task.
738  */
bpf_prog_run_pin_on_cpu(const struct bpf_prog * prog,const void * ctx)739 static inline u32 bpf_prog_run_pin_on_cpu(const struct bpf_prog *prog,
740 					  const void *ctx)
741 {
742 	u32 ret;
743 
744 	migrate_disable();
745 	ret = bpf_prog_run(prog, ctx);
746 	migrate_enable();
747 	return ret;
748 }
749 
750 #define BPF_SKB_CB_LEN QDISC_CB_PRIV_LEN
751 
752 struct bpf_skb_data_end {
753 	struct qdisc_skb_cb qdisc_cb;
754 	void *data_meta;
755 	void *data_end;
756 };
757 
758 struct bpf_nh_params {
759 	u32 nh_family;
760 	union {
761 		u32 ipv4_nh;
762 		struct in6_addr ipv6_nh;
763 	};
764 };
765 
766 /* flags for bpf_redirect_info kern_flags */
767 #define BPF_RI_F_RF_NO_DIRECT	BIT(0)	/* no napi_direct on return_frame */
768 #define BPF_RI_F_RI_INIT	BIT(1)
769 #define BPF_RI_F_CPU_MAP_INIT	BIT(2)
770 #define BPF_RI_F_DEV_MAP_INIT	BIT(3)
771 #define BPF_RI_F_XSK_MAP_INIT	BIT(4)
772 
773 struct bpf_redirect_info {
774 	u64 tgt_index;
775 	void *tgt_value;
776 	struct bpf_map *map;
777 	u32 flags;
778 	u32 map_id;
779 	enum bpf_map_type map_type;
780 	struct bpf_nh_params nh;
781 	u32 kern_flags;
782 };
783 
784 struct bpf_net_context {
785 	struct bpf_redirect_info ri;
786 	struct list_head cpu_map_flush_list;
787 	struct list_head dev_map_flush_list;
788 	struct list_head xskmap_map_flush_list;
789 };
790 
bpf_net_ctx_set(struct bpf_net_context * bpf_net_ctx)791 static inline struct bpf_net_context *bpf_net_ctx_set(struct bpf_net_context *bpf_net_ctx)
792 {
793 	struct task_struct *tsk = current;
794 
795 	if (tsk->bpf_net_context != NULL)
796 		return NULL;
797 	bpf_net_ctx->ri.kern_flags = 0;
798 
799 	tsk->bpf_net_context = bpf_net_ctx;
800 	return bpf_net_ctx;
801 }
802 
bpf_net_ctx_clear(struct bpf_net_context * bpf_net_ctx)803 static inline void bpf_net_ctx_clear(struct bpf_net_context *bpf_net_ctx)
804 {
805 	if (bpf_net_ctx)
806 		current->bpf_net_context = NULL;
807 }
808 
bpf_net_ctx_get(void)809 static inline struct bpf_net_context *bpf_net_ctx_get(void)
810 {
811 	return current->bpf_net_context;
812 }
813 
bpf_net_ctx_get_ri(void)814 static inline struct bpf_redirect_info *bpf_net_ctx_get_ri(void)
815 {
816 	struct bpf_net_context *bpf_net_ctx = bpf_net_ctx_get();
817 
818 	if (!(bpf_net_ctx->ri.kern_flags & BPF_RI_F_RI_INIT)) {
819 		memset(&bpf_net_ctx->ri, 0, offsetof(struct bpf_net_context, ri.nh));
820 		bpf_net_ctx->ri.kern_flags |= BPF_RI_F_RI_INIT;
821 	}
822 
823 	return &bpf_net_ctx->ri;
824 }
825 
bpf_net_ctx_get_cpu_map_flush_list(void)826 static inline struct list_head *bpf_net_ctx_get_cpu_map_flush_list(void)
827 {
828 	struct bpf_net_context *bpf_net_ctx = bpf_net_ctx_get();
829 
830 	if (!(bpf_net_ctx->ri.kern_flags & BPF_RI_F_CPU_MAP_INIT)) {
831 		INIT_LIST_HEAD(&bpf_net_ctx->cpu_map_flush_list);
832 		bpf_net_ctx->ri.kern_flags |= BPF_RI_F_CPU_MAP_INIT;
833 	}
834 
835 	return &bpf_net_ctx->cpu_map_flush_list;
836 }
837 
bpf_net_ctx_get_dev_flush_list(void)838 static inline struct list_head *bpf_net_ctx_get_dev_flush_list(void)
839 {
840 	struct bpf_net_context *bpf_net_ctx = bpf_net_ctx_get();
841 
842 	if (!(bpf_net_ctx->ri.kern_flags & BPF_RI_F_DEV_MAP_INIT)) {
843 		INIT_LIST_HEAD(&bpf_net_ctx->dev_map_flush_list);
844 		bpf_net_ctx->ri.kern_flags |= BPF_RI_F_DEV_MAP_INIT;
845 	}
846 
847 	return &bpf_net_ctx->dev_map_flush_list;
848 }
849 
bpf_net_ctx_get_xskmap_flush_list(void)850 static inline struct list_head *bpf_net_ctx_get_xskmap_flush_list(void)
851 {
852 	struct bpf_net_context *bpf_net_ctx = bpf_net_ctx_get();
853 
854 	if (!(bpf_net_ctx->ri.kern_flags & BPF_RI_F_XSK_MAP_INIT)) {
855 		INIT_LIST_HEAD(&bpf_net_ctx->xskmap_map_flush_list);
856 		bpf_net_ctx->ri.kern_flags |= BPF_RI_F_XSK_MAP_INIT;
857 	}
858 
859 	return &bpf_net_ctx->xskmap_map_flush_list;
860 }
861 
bpf_net_ctx_get_all_used_flush_lists(struct list_head ** lh_map,struct list_head ** lh_dev,struct list_head ** lh_xsk)862 static inline void bpf_net_ctx_get_all_used_flush_lists(struct list_head **lh_map,
863 							struct list_head **lh_dev,
864 							struct list_head **lh_xsk)
865 {
866 	struct bpf_net_context *bpf_net_ctx = bpf_net_ctx_get();
867 	u32 kern_flags = bpf_net_ctx->ri.kern_flags;
868 	struct list_head *lh;
869 
870 	*lh_map = *lh_dev = *lh_xsk = NULL;
871 
872 	if (!IS_ENABLED(CONFIG_BPF_SYSCALL))
873 		return;
874 
875 	lh = &bpf_net_ctx->dev_map_flush_list;
876 	if (kern_flags & BPF_RI_F_DEV_MAP_INIT && !list_empty(lh))
877 		*lh_dev = lh;
878 
879 	lh = &bpf_net_ctx->cpu_map_flush_list;
880 	if (kern_flags & BPF_RI_F_CPU_MAP_INIT && !list_empty(lh))
881 		*lh_map = lh;
882 
883 	lh = &bpf_net_ctx->xskmap_map_flush_list;
884 	if (IS_ENABLED(CONFIG_XDP_SOCKETS) &&
885 	    kern_flags & BPF_RI_F_XSK_MAP_INIT && !list_empty(lh))
886 		*lh_xsk = lh;
887 }
888 
889 /* Compute the linear packet data range [data, data_end) which
890  * will be accessed by various program types (cls_bpf, act_bpf,
891  * lwt, ...). Subsystems allowing direct data access must (!)
892  * ensure that cb[] area can be written to when BPF program is
893  * invoked (otherwise cb[] save/restore is necessary).
894  */
bpf_compute_data_pointers(struct sk_buff * skb)895 static inline void bpf_compute_data_pointers(struct sk_buff *skb)
896 {
897 	struct bpf_skb_data_end *cb = (struct bpf_skb_data_end *)skb->cb;
898 
899 	BUILD_BUG_ON(sizeof(*cb) > sizeof_field(struct sk_buff, cb));
900 	cb->data_meta = skb->data - skb_metadata_len(skb);
901 	cb->data_end  = skb->data + skb_headlen(skb);
902 }
903 
904 /* Similar to bpf_compute_data_pointers(), except that save orginal
905  * data in cb->data and cb->meta_data for restore.
906  */
bpf_compute_and_save_data_end(struct sk_buff * skb,void ** saved_data_end)907 static inline void bpf_compute_and_save_data_end(
908 	struct sk_buff *skb, void **saved_data_end)
909 {
910 	struct bpf_skb_data_end *cb = (struct bpf_skb_data_end *)skb->cb;
911 
912 	*saved_data_end = cb->data_end;
913 	cb->data_end  = skb->data + skb_headlen(skb);
914 }
915 
916 /* Restore data saved by bpf_compute_and_save_data_end(). */
bpf_restore_data_end(struct sk_buff * skb,void * saved_data_end)917 static inline void bpf_restore_data_end(
918 	struct sk_buff *skb, void *saved_data_end)
919 {
920 	struct bpf_skb_data_end *cb = (struct bpf_skb_data_end *)skb->cb;
921 
922 	cb->data_end = saved_data_end;
923 }
924 
bpf_skb_cb(const struct sk_buff * skb)925 static inline u8 *bpf_skb_cb(const struct sk_buff *skb)
926 {
927 	/* eBPF programs may read/write skb->cb[] area to transfer meta
928 	 * data between tail calls. Since this also needs to work with
929 	 * tc, that scratch memory is mapped to qdisc_skb_cb's data area.
930 	 *
931 	 * In some socket filter cases, the cb unfortunately needs to be
932 	 * saved/restored so that protocol specific skb->cb[] data won't
933 	 * be lost. In any case, due to unpriviledged eBPF programs
934 	 * attached to sockets, we need to clear the bpf_skb_cb() area
935 	 * to not leak previous contents to user space.
936 	 */
937 	BUILD_BUG_ON(sizeof_field(struct __sk_buff, cb) != BPF_SKB_CB_LEN);
938 	BUILD_BUG_ON(sizeof_field(struct __sk_buff, cb) !=
939 		     sizeof_field(struct qdisc_skb_cb, data));
940 
941 	return qdisc_skb_cb(skb)->data;
942 }
943 
944 /* Must be invoked with migration disabled */
__bpf_prog_run_save_cb(const struct bpf_prog * prog,const void * ctx)945 static inline u32 __bpf_prog_run_save_cb(const struct bpf_prog *prog,
946 					 const void *ctx)
947 {
948 	const struct sk_buff *skb = ctx;
949 	u8 *cb_data = bpf_skb_cb(skb);
950 	u8 cb_saved[BPF_SKB_CB_LEN];
951 	u32 res;
952 
953 	if (unlikely(prog->cb_access)) {
954 		memcpy(cb_saved, cb_data, sizeof(cb_saved));
955 		memset(cb_data, 0, sizeof(cb_saved));
956 	}
957 
958 	res = bpf_prog_run(prog, skb);
959 
960 	if (unlikely(prog->cb_access))
961 		memcpy(cb_data, cb_saved, sizeof(cb_saved));
962 
963 	return res;
964 }
965 
bpf_prog_run_save_cb(const struct bpf_prog * prog,struct sk_buff * skb)966 static inline u32 bpf_prog_run_save_cb(const struct bpf_prog *prog,
967 				       struct sk_buff *skb)
968 {
969 	u32 res;
970 
971 	migrate_disable();
972 	res = __bpf_prog_run_save_cb(prog, skb);
973 	migrate_enable();
974 	return res;
975 }
976 
bpf_prog_run_clear_cb(const struct bpf_prog * prog,struct sk_buff * skb)977 static inline u32 bpf_prog_run_clear_cb(const struct bpf_prog *prog,
978 					struct sk_buff *skb)
979 {
980 	u8 *cb_data = bpf_skb_cb(skb);
981 	u32 res;
982 
983 	if (unlikely(prog->cb_access))
984 		memset(cb_data, 0, BPF_SKB_CB_LEN);
985 
986 	res = bpf_prog_run_pin_on_cpu(prog, skb);
987 	return res;
988 }
989 
990 DECLARE_BPF_DISPATCHER(xdp)
991 
992 DECLARE_STATIC_KEY_FALSE(bpf_master_redirect_enabled_key);
993 
994 u32 xdp_master_redirect(struct xdp_buff *xdp);
995 
996 void bpf_prog_change_xdp(struct bpf_prog *prev_prog, struct bpf_prog *prog);
997 
bpf_prog_insn_size(const struct bpf_prog * prog)998 static inline u32 bpf_prog_insn_size(const struct bpf_prog *prog)
999 {
1000 	return prog->len * sizeof(struct bpf_insn);
1001 }
1002 
bpf_prog_size(unsigned int proglen)1003 static inline unsigned int bpf_prog_size(unsigned int proglen)
1004 {
1005 	return max(sizeof(struct bpf_prog),
1006 		   offsetof(struct bpf_prog, insns[proglen]));
1007 }
1008 
bpf_prog_was_classic(const struct bpf_prog * prog)1009 static inline bool bpf_prog_was_classic(const struct bpf_prog *prog)
1010 {
1011 	/* When classic BPF programs have been loaded and the arch
1012 	 * does not have a classic BPF JIT (anymore), they have been
1013 	 * converted via bpf_migrate_filter() to eBPF and thus always
1014 	 * have an unspec program type.
1015 	 */
1016 	return prog->type == BPF_PROG_TYPE_UNSPEC;
1017 }
1018 
bpf_ctx_off_adjust_machine(u32 size)1019 static inline u32 bpf_ctx_off_adjust_machine(u32 size)
1020 {
1021 	const u32 size_machine = sizeof(unsigned long);
1022 
1023 	if (size > size_machine && size % size_machine == 0)
1024 		size = size_machine;
1025 
1026 	return size;
1027 }
1028 
1029 static inline bool
bpf_ctx_narrow_access_ok(u32 off,u32 size,u32 size_default)1030 bpf_ctx_narrow_access_ok(u32 off, u32 size, u32 size_default)
1031 {
1032 	return size <= size_default && (size & (size - 1)) == 0;
1033 }
1034 
1035 static inline u8
bpf_ctx_narrow_access_offset(u32 off,u32 size,u32 size_default)1036 bpf_ctx_narrow_access_offset(u32 off, u32 size, u32 size_default)
1037 {
1038 	u8 access_off = off & (size_default - 1);
1039 
1040 #ifdef __LITTLE_ENDIAN
1041 	return access_off;
1042 #else
1043 	return size_default - (access_off + size);
1044 #endif
1045 }
1046 
1047 #define bpf_ctx_wide_access_ok(off, size, type, field)			\
1048 	(size == sizeof(__u64) &&					\
1049 	off >= offsetof(type, field) &&					\
1050 	off + sizeof(__u64) <= offsetofend(type, field) &&		\
1051 	off % sizeof(__u64) == 0)
1052 
1053 #define bpf_classic_proglen(fprog) (fprog->len * sizeof(fprog->filter[0]))
1054 
bpf_prog_lock_ro(struct bpf_prog * fp)1055 static inline int __must_check bpf_prog_lock_ro(struct bpf_prog *fp)
1056 {
1057 #ifndef CONFIG_BPF_JIT_ALWAYS_ON
1058 	if (!fp->jited) {
1059 		set_vm_flush_reset_perms(fp);
1060 		return set_memory_ro((unsigned long)fp, fp->pages);
1061 	}
1062 #endif
1063 	return 0;
1064 }
1065 
1066 static inline int __must_check
bpf_jit_binary_lock_ro(struct bpf_binary_header * hdr)1067 bpf_jit_binary_lock_ro(struct bpf_binary_header *hdr)
1068 {
1069 	set_vm_flush_reset_perms(hdr);
1070 	return set_memory_rox((unsigned long)hdr, hdr->size >> PAGE_SHIFT);
1071 }
1072 
1073 int sk_filter_trim_cap(struct sock *sk, struct sk_buff *skb, unsigned int cap,
1074 		       enum skb_drop_reason *reason);
1075 
sk_filter(struct sock * sk,struct sk_buff * skb)1076 static inline int sk_filter(struct sock *sk, struct sk_buff *skb)
1077 {
1078 	enum skb_drop_reason ignore_reason;
1079 
1080 	return sk_filter_trim_cap(sk, skb, 1, &ignore_reason);
1081 }
1082 
sk_filter_reason(struct sock * sk,struct sk_buff * skb,enum skb_drop_reason * reason)1083 static inline int sk_filter_reason(struct sock *sk, struct sk_buff *skb,
1084 				   enum skb_drop_reason *reason)
1085 {
1086 	return sk_filter_trim_cap(sk, skb, 1, reason);
1087 }
1088 
1089 struct bpf_prog *bpf_prog_select_runtime(struct bpf_prog *fp, int *err);
1090 void bpf_prog_free(struct bpf_prog *fp);
1091 
1092 bool bpf_opcode_in_insntable(u8 code);
1093 
1094 void bpf_prog_fill_jited_linfo(struct bpf_prog *prog,
1095 			       const u32 *insn_to_jit_off);
1096 int bpf_prog_alloc_jited_linfo(struct bpf_prog *prog);
1097 void bpf_prog_jit_attempt_done(struct bpf_prog *prog);
1098 
1099 struct bpf_prog *bpf_prog_alloc(unsigned int size, gfp_t gfp_extra_flags);
1100 struct bpf_prog *bpf_prog_alloc_no_stats(unsigned int size, gfp_t gfp_extra_flags);
1101 struct bpf_prog *bpf_prog_realloc(struct bpf_prog *fp_old, unsigned int size,
1102 				  gfp_t gfp_extra_flags);
1103 void __bpf_prog_free(struct bpf_prog *fp);
1104 
bpf_prog_unlock_free(struct bpf_prog * fp)1105 static inline void bpf_prog_unlock_free(struct bpf_prog *fp)
1106 {
1107 	__bpf_prog_free(fp);
1108 }
1109 
1110 typedef int (*bpf_aux_classic_check_t)(struct sock_filter *filter,
1111 				       unsigned int flen);
1112 
1113 int bpf_prog_create(struct bpf_prog **pfp, struct sock_fprog_kern *fprog);
1114 int bpf_prog_create_from_user(struct bpf_prog **pfp, struct sock_fprog *fprog,
1115 			      bpf_aux_classic_check_t trans, bool save_orig);
1116 void bpf_prog_destroy(struct bpf_prog *fp);
1117 
1118 int sk_attach_filter(struct sock_fprog *fprog, struct sock *sk);
1119 int sk_attach_bpf(u32 ufd, struct sock *sk);
1120 int sk_reuseport_attach_filter(struct sock_fprog *fprog, struct sock *sk);
1121 int sk_reuseport_attach_bpf(u32 ufd, struct sock *sk);
1122 void sk_reuseport_prog_free(struct bpf_prog *prog);
1123 int sk_detach_filter(struct sock *sk);
1124 int sk_get_filter(struct sock *sk, sockptr_t optval, unsigned int len);
1125 
1126 bool sk_filter_charge(struct sock *sk, struct sk_filter *fp);
1127 void sk_filter_uncharge(struct sock *sk, struct sk_filter *fp);
1128 
1129 u64 __bpf_call_base(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5);
1130 #define __bpf_call_base_args \
1131 	((u64 (*)(u64, u64, u64, u64, u64, const struct bpf_insn *)) \
1132 	 (void *)__bpf_call_base)
1133 
1134 struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog);
1135 void bpf_jit_compile(struct bpf_prog *prog);
1136 bool bpf_jit_needs_zext(void);
1137 bool bpf_jit_inlines_helper_call(s32 imm);
1138 bool bpf_jit_supports_subprog_tailcalls(void);
1139 bool bpf_jit_supports_percpu_insn(void);
1140 bool bpf_jit_supports_kfunc_call(void);
1141 bool bpf_jit_supports_far_kfunc_call(void);
1142 bool bpf_jit_supports_exceptions(void);
1143 bool bpf_jit_supports_ptr_xchg(void);
1144 bool bpf_jit_supports_arena(void);
1145 bool bpf_jit_supports_insn(struct bpf_insn *insn, bool in_arena);
1146 bool bpf_jit_supports_private_stack(void);
1147 bool bpf_jit_supports_timed_may_goto(void);
1148 u64 bpf_arch_uaddress_limit(void);
1149 void arch_bpf_stack_walk(bool (*consume_fn)(void *cookie, u64 ip, u64 sp, u64 bp), void *cookie);
1150 u64 arch_bpf_timed_may_goto(void);
1151 u64 bpf_check_timed_may_goto(struct bpf_timed_may_goto *);
1152 bool bpf_helper_changes_pkt_data(enum bpf_func_id func_id);
1153 
bpf_dump_raw_ok(const struct cred * cred)1154 static inline bool bpf_dump_raw_ok(const struct cred *cred)
1155 {
1156 	/* Reconstruction of call-sites is dependent on kallsyms,
1157 	 * thus make dump the same restriction.
1158 	 */
1159 	return kallsyms_show_value(cred);
1160 }
1161 
1162 struct bpf_prog *bpf_patch_insn_single(struct bpf_prog *prog, u32 off,
1163 				       const struct bpf_insn *patch, u32 len);
1164 int bpf_remove_insns(struct bpf_prog *prog, u32 off, u32 cnt);
1165 
xdp_return_frame_no_direct(void)1166 static inline bool xdp_return_frame_no_direct(void)
1167 {
1168 	struct bpf_redirect_info *ri = bpf_net_ctx_get_ri();
1169 
1170 	return ri->kern_flags & BPF_RI_F_RF_NO_DIRECT;
1171 }
1172 
xdp_set_return_frame_no_direct(void)1173 static inline void xdp_set_return_frame_no_direct(void)
1174 {
1175 	struct bpf_redirect_info *ri = bpf_net_ctx_get_ri();
1176 
1177 	ri->kern_flags |= BPF_RI_F_RF_NO_DIRECT;
1178 }
1179 
xdp_clear_return_frame_no_direct(void)1180 static inline void xdp_clear_return_frame_no_direct(void)
1181 {
1182 	struct bpf_redirect_info *ri = bpf_net_ctx_get_ri();
1183 
1184 	ri->kern_flags &= ~BPF_RI_F_RF_NO_DIRECT;
1185 }
1186 
xdp_ok_fwd_dev(const struct net_device * fwd,unsigned int pktlen)1187 static inline int xdp_ok_fwd_dev(const struct net_device *fwd,
1188 				 unsigned int pktlen)
1189 {
1190 	unsigned int len;
1191 
1192 	if (unlikely(!(fwd->flags & IFF_UP)))
1193 		return -ENETDOWN;
1194 
1195 	len = fwd->mtu + fwd->hard_header_len + VLAN_HLEN;
1196 	if (pktlen > len)
1197 		return -EMSGSIZE;
1198 
1199 	return 0;
1200 }
1201 
1202 /* The pair of xdp_do_redirect and xdp_do_flush MUST be called in the
1203  * same cpu context. Further for best results no more than a single map
1204  * for the do_redirect/do_flush pair should be used. This limitation is
1205  * because we only track one map and force a flush when the map changes.
1206  * This does not appear to be a real limitation for existing software.
1207  */
1208 int xdp_do_generic_redirect(struct net_device *dev, struct sk_buff *skb,
1209 			    struct xdp_buff *xdp, const struct bpf_prog *prog);
1210 int xdp_do_redirect(struct net_device *dev,
1211 		    struct xdp_buff *xdp,
1212 		    const struct bpf_prog *prog);
1213 int xdp_do_redirect_frame(struct net_device *dev,
1214 			  struct xdp_buff *xdp,
1215 			  struct xdp_frame *xdpf,
1216 			  const struct bpf_prog *prog);
1217 void xdp_do_flush(void);
1218 
1219 void bpf_warn_invalid_xdp_action(const struct net_device *dev,
1220 				 const struct bpf_prog *prog, u32 act);
1221 
1222 #ifdef CONFIG_INET
1223 struct sock *bpf_run_sk_reuseport(struct sock_reuseport *reuse, struct sock *sk,
1224 				  struct bpf_prog *prog, struct sk_buff *skb,
1225 				  struct sock *migrating_sk,
1226 				  u32 hash);
1227 #else
1228 static inline struct sock *
bpf_run_sk_reuseport(struct sock_reuseport * reuse,struct sock * sk,struct bpf_prog * prog,struct sk_buff * skb,struct sock * migrating_sk,u32 hash)1229 bpf_run_sk_reuseport(struct sock_reuseport *reuse, struct sock *sk,
1230 		     struct bpf_prog *prog, struct sk_buff *skb,
1231 		     struct sock *migrating_sk,
1232 		     u32 hash)
1233 {
1234 	return NULL;
1235 }
1236 #endif
1237 
1238 #ifdef CONFIG_BPF_JIT
1239 extern int bpf_jit_enable;
1240 extern int bpf_jit_harden;
1241 extern int bpf_jit_kallsyms;
1242 extern long bpf_jit_limit;
1243 extern long bpf_jit_limit_max;
1244 
1245 typedef void (*bpf_jit_fill_hole_t)(void *area, unsigned int size);
1246 
1247 void bpf_jit_fill_hole_with_zero(void *area, unsigned int size);
1248 
1249 struct bpf_binary_header *
1250 bpf_jit_binary_alloc(unsigned int proglen, u8 **image_ptr,
1251 		     unsigned int alignment,
1252 		     bpf_jit_fill_hole_t bpf_fill_ill_insns);
1253 void bpf_jit_binary_free(struct bpf_binary_header *hdr);
1254 u64 bpf_jit_alloc_exec_limit(void);
1255 void *bpf_jit_alloc_exec(unsigned long size);
1256 void bpf_jit_free_exec(void *addr);
1257 void bpf_jit_free(struct bpf_prog *fp);
1258 struct bpf_binary_header *
1259 bpf_jit_binary_pack_hdr(const struct bpf_prog *fp);
1260 
1261 void *bpf_prog_pack_alloc(u32 size, bpf_jit_fill_hole_t bpf_fill_ill_insns);
1262 void bpf_prog_pack_free(void *ptr, u32 size);
1263 
bpf_prog_kallsyms_verify_off(const struct bpf_prog * fp)1264 static inline bool bpf_prog_kallsyms_verify_off(const struct bpf_prog *fp)
1265 {
1266 	return list_empty(&fp->aux->ksym.lnode) ||
1267 	       fp->aux->ksym.lnode.prev == LIST_POISON2;
1268 }
1269 
1270 struct bpf_binary_header *
1271 bpf_jit_binary_pack_alloc(unsigned int proglen, u8 **ro_image,
1272 			  unsigned int alignment,
1273 			  struct bpf_binary_header **rw_hdr,
1274 			  u8 **rw_image,
1275 			  bpf_jit_fill_hole_t bpf_fill_ill_insns);
1276 int bpf_jit_binary_pack_finalize(struct bpf_binary_header *ro_header,
1277 				 struct bpf_binary_header *rw_header);
1278 void bpf_jit_binary_pack_free(struct bpf_binary_header *ro_header,
1279 			      struct bpf_binary_header *rw_header);
1280 
1281 int bpf_jit_add_poke_descriptor(struct bpf_prog *prog,
1282 				struct bpf_jit_poke_descriptor *poke);
1283 
1284 int bpf_jit_get_func_addr(const struct bpf_prog *prog,
1285 			  const struct bpf_insn *insn, bool extra_pass,
1286 			  u64 *func_addr, bool *func_addr_fixed);
1287 
1288 const char *bpf_jit_get_prog_name(struct bpf_prog *prog);
1289 
1290 struct bpf_prog *bpf_jit_blind_constants(struct bpf_prog *fp);
1291 void bpf_jit_prog_release_other(struct bpf_prog *fp, struct bpf_prog *fp_other);
1292 
bpf_jit_dump(unsigned int flen,unsigned int proglen,u32 pass,void * image)1293 static inline void bpf_jit_dump(unsigned int flen, unsigned int proglen,
1294 				u32 pass, void *image)
1295 {
1296 	pr_err("flen=%u proglen=%u pass=%u image=%p from=%s pid=%d\n", flen,
1297 	       proglen, pass, image, current->comm, task_pid_nr(current));
1298 
1299 	if (image)
1300 		print_hex_dump(KERN_ERR, "JIT code: ", DUMP_PREFIX_OFFSET,
1301 			       16, 1, image, proglen, false);
1302 }
1303 
bpf_jit_is_ebpf(void)1304 static inline bool bpf_jit_is_ebpf(void)
1305 {
1306 # ifdef CONFIG_HAVE_EBPF_JIT
1307 	return true;
1308 # else
1309 	return false;
1310 # endif
1311 }
1312 
ebpf_jit_enabled(void)1313 static inline bool ebpf_jit_enabled(void)
1314 {
1315 	return bpf_jit_enable && bpf_jit_is_ebpf();
1316 }
1317 
bpf_prog_ebpf_jited(const struct bpf_prog * fp)1318 static inline bool bpf_prog_ebpf_jited(const struct bpf_prog *fp)
1319 {
1320 	return fp->jited && bpf_jit_is_ebpf();
1321 }
1322 
bpf_jit_blinding_enabled(struct bpf_prog * prog)1323 static inline bool bpf_jit_blinding_enabled(struct bpf_prog *prog)
1324 {
1325 	/* These are the prerequisites, should someone ever have the
1326 	 * idea to call blinding outside of them, we make sure to
1327 	 * bail out.
1328 	 */
1329 	if (!bpf_jit_is_ebpf())
1330 		return false;
1331 	if (!prog->jit_requested)
1332 		return false;
1333 	if (!bpf_jit_harden)
1334 		return false;
1335 	if (bpf_jit_harden == 1 && bpf_token_capable(prog->aux->token, CAP_BPF))
1336 		return false;
1337 
1338 	return true;
1339 }
1340 
bpf_jit_kallsyms_enabled(void)1341 static inline bool bpf_jit_kallsyms_enabled(void)
1342 {
1343 	/* There are a couple of corner cases where kallsyms should
1344 	 * not be enabled f.e. on hardening.
1345 	 */
1346 	if (bpf_jit_harden)
1347 		return false;
1348 	if (!bpf_jit_kallsyms)
1349 		return false;
1350 	if (bpf_jit_kallsyms == 1)
1351 		return true;
1352 
1353 	return false;
1354 }
1355 
1356 int __bpf_address_lookup(unsigned long addr, unsigned long *size,
1357 				 unsigned long *off, char *sym);
1358 bool is_bpf_text_address(unsigned long addr);
1359 int bpf_get_kallsym(unsigned int symnum, unsigned long *value, char *type,
1360 		    char *sym);
1361 struct bpf_prog *bpf_prog_ksym_find(unsigned long addr);
1362 
1363 static inline int
bpf_address_lookup(unsigned long addr,unsigned long * size,unsigned long * off,char ** modname,char * sym)1364 bpf_address_lookup(unsigned long addr, unsigned long *size,
1365 		   unsigned long *off, char **modname, char *sym)
1366 {
1367 	int ret = __bpf_address_lookup(addr, size, off, sym);
1368 
1369 	if (ret && modname)
1370 		*modname = NULL;
1371 	return ret;
1372 }
1373 
1374 void bpf_prog_kallsyms_add(struct bpf_prog *fp);
1375 void bpf_prog_kallsyms_del(struct bpf_prog *fp);
1376 
1377 #else /* CONFIG_BPF_JIT */
1378 
ebpf_jit_enabled(void)1379 static inline bool ebpf_jit_enabled(void)
1380 {
1381 	return false;
1382 }
1383 
bpf_jit_blinding_enabled(struct bpf_prog * prog)1384 static inline bool bpf_jit_blinding_enabled(struct bpf_prog *prog)
1385 {
1386 	return false;
1387 }
1388 
bpf_prog_ebpf_jited(const struct bpf_prog * fp)1389 static inline bool bpf_prog_ebpf_jited(const struct bpf_prog *fp)
1390 {
1391 	return false;
1392 }
1393 
1394 static inline int
bpf_jit_add_poke_descriptor(struct bpf_prog * prog,struct bpf_jit_poke_descriptor * poke)1395 bpf_jit_add_poke_descriptor(struct bpf_prog *prog,
1396 			    struct bpf_jit_poke_descriptor *poke)
1397 {
1398 	return -ENOTSUPP;
1399 }
1400 
bpf_jit_free(struct bpf_prog * fp)1401 static inline void bpf_jit_free(struct bpf_prog *fp)
1402 {
1403 	bpf_prog_unlock_free(fp);
1404 }
1405 
bpf_jit_kallsyms_enabled(void)1406 static inline bool bpf_jit_kallsyms_enabled(void)
1407 {
1408 	return false;
1409 }
1410 
1411 static inline int
__bpf_address_lookup(unsigned long addr,unsigned long * size,unsigned long * off,char * sym)1412 __bpf_address_lookup(unsigned long addr, unsigned long *size,
1413 		     unsigned long *off, char *sym)
1414 {
1415 	return 0;
1416 }
1417 
is_bpf_text_address(unsigned long addr)1418 static inline bool is_bpf_text_address(unsigned long addr)
1419 {
1420 	return false;
1421 }
1422 
bpf_get_kallsym(unsigned int symnum,unsigned long * value,char * type,char * sym)1423 static inline int bpf_get_kallsym(unsigned int symnum, unsigned long *value,
1424 				  char *type, char *sym)
1425 {
1426 	return -ERANGE;
1427 }
1428 
bpf_prog_ksym_find(unsigned long addr)1429 static inline struct bpf_prog *bpf_prog_ksym_find(unsigned long addr)
1430 {
1431 	return NULL;
1432 }
1433 
1434 static inline int
bpf_address_lookup(unsigned long addr,unsigned long * size,unsigned long * off,char ** modname,char * sym)1435 bpf_address_lookup(unsigned long addr, unsigned long *size,
1436 		   unsigned long *off, char **modname, char *sym)
1437 {
1438 	return 0;
1439 }
1440 
bpf_prog_kallsyms_add(struct bpf_prog * fp)1441 static inline void bpf_prog_kallsyms_add(struct bpf_prog *fp)
1442 {
1443 }
1444 
bpf_prog_kallsyms_del(struct bpf_prog * fp)1445 static inline void bpf_prog_kallsyms_del(struct bpf_prog *fp)
1446 {
1447 }
1448 
1449 #endif /* CONFIG_BPF_JIT */
1450 
1451 void bpf_prog_kallsyms_del_all(struct bpf_prog *fp);
1452 
1453 #define BPF_ANC		BIT(15)
1454 
bpf_needs_clear_a(const struct sock_filter * first)1455 static inline bool bpf_needs_clear_a(const struct sock_filter *first)
1456 {
1457 	switch (first->code) {
1458 	case BPF_RET | BPF_K:
1459 	case BPF_LD | BPF_W | BPF_LEN:
1460 		return false;
1461 
1462 	case BPF_LD | BPF_W | BPF_ABS:
1463 	case BPF_LD | BPF_H | BPF_ABS:
1464 	case BPF_LD | BPF_B | BPF_ABS:
1465 		if (first->k == SKF_AD_OFF + SKF_AD_ALU_XOR_X)
1466 			return true;
1467 		return false;
1468 
1469 	default:
1470 		return true;
1471 	}
1472 }
1473 
bpf_anc_helper(const struct sock_filter * ftest)1474 static inline u16 bpf_anc_helper(const struct sock_filter *ftest)
1475 {
1476 	BUG_ON(ftest->code & BPF_ANC);
1477 
1478 	switch (ftest->code) {
1479 	case BPF_LD | BPF_W | BPF_ABS:
1480 	case BPF_LD | BPF_H | BPF_ABS:
1481 	case BPF_LD | BPF_B | BPF_ABS:
1482 #define BPF_ANCILLARY(CODE)	case SKF_AD_OFF + SKF_AD_##CODE:	\
1483 				return BPF_ANC | SKF_AD_##CODE
1484 		switch (ftest->k) {
1485 		BPF_ANCILLARY(PROTOCOL);
1486 		BPF_ANCILLARY(PKTTYPE);
1487 		BPF_ANCILLARY(IFINDEX);
1488 		BPF_ANCILLARY(NLATTR);
1489 		BPF_ANCILLARY(NLATTR_NEST);
1490 		BPF_ANCILLARY(MARK);
1491 		BPF_ANCILLARY(QUEUE);
1492 		BPF_ANCILLARY(HATYPE);
1493 		BPF_ANCILLARY(RXHASH);
1494 		BPF_ANCILLARY(CPU);
1495 		BPF_ANCILLARY(ALU_XOR_X);
1496 		BPF_ANCILLARY(VLAN_TAG);
1497 		BPF_ANCILLARY(VLAN_TAG_PRESENT);
1498 		BPF_ANCILLARY(PAY_OFFSET);
1499 		BPF_ANCILLARY(RANDOM);
1500 		BPF_ANCILLARY(VLAN_TPID);
1501 		}
1502 		fallthrough;
1503 	default:
1504 		return ftest->code;
1505 	}
1506 }
1507 
1508 void *bpf_internal_load_pointer_neg_helper(const struct sk_buff *skb,
1509 					   int k, unsigned int size);
1510 
bpf_tell_extensions(void)1511 static inline int bpf_tell_extensions(void)
1512 {
1513 	return SKF_AD_MAX;
1514 }
1515 
1516 struct bpf_sock_addr_kern {
1517 	struct sock *sk;
1518 	struct sockaddr *uaddr;
1519 	/* Temporary "register" to make indirect stores to nested structures
1520 	 * defined above. We need three registers to make such a store, but
1521 	 * only two (src and dst) are available at convert_ctx_access time
1522 	 */
1523 	u64 tmp_reg;
1524 	void *t_ctx;	/* Attach type specific context. */
1525 	u32 uaddrlen;
1526 };
1527 
1528 struct bpf_sock_ops_kern {
1529 	struct	sock *sk;
1530 	union {
1531 		u32 args[4];
1532 		u32 reply;
1533 		u32 replylong[4];
1534 	};
1535 	struct sk_buff	*syn_skb;
1536 	struct sk_buff	*skb;
1537 	void	*skb_data_end;
1538 	u8	op;
1539 	u8	is_fullsock;
1540 	u8	is_locked_tcp_sock;
1541 	u8	remaining_opt_len;
1542 	u64	temp;			/* temp and everything after is not
1543 					 * initialized to 0 before calling
1544 					 * the BPF program. New fields that
1545 					 * should be initialized to 0 should
1546 					 * be inserted before temp.
1547 					 * temp is scratch storage used by
1548 					 * sock_ops_convert_ctx_access
1549 					 * as temporary storage of a register.
1550 					 */
1551 };
1552 
1553 struct bpf_sysctl_kern {
1554 	struct ctl_table_header *head;
1555 	const struct ctl_table *table;
1556 	void *cur_val;
1557 	size_t cur_len;
1558 	void *new_val;
1559 	size_t new_len;
1560 	int new_updated;
1561 	int write;
1562 	loff_t *ppos;
1563 	/* Temporary "register" for indirect stores to ppos. */
1564 	u64 tmp_reg;
1565 };
1566 
1567 #define BPF_SOCKOPT_KERN_BUF_SIZE	32
1568 struct bpf_sockopt_buf {
1569 	u8		data[BPF_SOCKOPT_KERN_BUF_SIZE];
1570 };
1571 
1572 struct bpf_sockopt_kern {
1573 	struct sock	*sk;
1574 	u8		*optval;
1575 	u8		*optval_end;
1576 	s32		level;
1577 	s32		optname;
1578 	s32		optlen;
1579 	/* for retval in struct bpf_cg_run_ctx */
1580 	struct task_struct *current_task;
1581 	/* Temporary "register" for indirect stores to ppos. */
1582 	u64		tmp_reg;
1583 };
1584 
1585 int copy_bpf_fprog_from_user(struct sock_fprog *dst, sockptr_t src, int len);
1586 
1587 struct bpf_sk_lookup_kern {
1588 	u16		family;
1589 	u16		protocol;
1590 	__be16		sport;
1591 	u16		dport;
1592 	struct {
1593 		__be32 saddr;
1594 		__be32 daddr;
1595 	} v4;
1596 	struct {
1597 		const struct in6_addr *saddr;
1598 		const struct in6_addr *daddr;
1599 	} v6;
1600 	struct sock	*selected_sk;
1601 	u32		ingress_ifindex;
1602 	bool		no_reuseport;
1603 };
1604 
1605 extern struct static_key_false bpf_sk_lookup_enabled;
1606 
1607 /* Runners for BPF_SK_LOOKUP programs to invoke on socket lookup.
1608  *
1609  * Allowed return values for a BPF SK_LOOKUP program are SK_PASS and
1610  * SK_DROP. Their meaning is as follows:
1611  *
1612  *  SK_PASS && ctx.selected_sk != NULL: use selected_sk as lookup result
1613  *  SK_PASS && ctx.selected_sk == NULL: continue to htable-based socket lookup
1614  *  SK_DROP                           : terminate lookup with -ECONNREFUSED
1615  *
1616  * This macro aggregates return values and selected sockets from
1617  * multiple BPF programs according to following rules in order:
1618  *
1619  *  1. If any program returned SK_PASS and a non-NULL ctx.selected_sk,
1620  *     macro result is SK_PASS and last ctx.selected_sk is used.
1621  *  2. If any program returned SK_DROP return value,
1622  *     macro result is SK_DROP.
1623  *  3. Otherwise result is SK_PASS and ctx.selected_sk is NULL.
1624  *
1625  * Caller must ensure that the prog array is non-NULL, and that the
1626  * array as well as the programs it contains remain valid.
1627  */
1628 #define BPF_PROG_SK_LOOKUP_RUN_ARRAY(array, ctx, func)			\
1629 	({								\
1630 		struct bpf_sk_lookup_kern *_ctx = &(ctx);		\
1631 		struct bpf_prog_array_item *_item;			\
1632 		struct sock *_selected_sk = NULL;			\
1633 		bool _no_reuseport = false;				\
1634 		struct bpf_prog *_prog;					\
1635 		bool _all_pass = true;					\
1636 		u32 _ret;						\
1637 									\
1638 		migrate_disable();					\
1639 		_item = &(array)->items[0];				\
1640 		while ((_prog = READ_ONCE(_item->prog))) {		\
1641 			/* restore most recent selection */		\
1642 			_ctx->selected_sk = _selected_sk;		\
1643 			_ctx->no_reuseport = _no_reuseport;		\
1644 									\
1645 			_ret = func(_prog, _ctx);			\
1646 			if (_ret == SK_PASS && _ctx->selected_sk) {	\
1647 				/* remember last non-NULL socket */	\
1648 				_selected_sk = _ctx->selected_sk;	\
1649 				_no_reuseport = _ctx->no_reuseport;	\
1650 			} else if (_ret == SK_DROP && _all_pass) {	\
1651 				_all_pass = false;			\
1652 			}						\
1653 			_item++;					\
1654 		}							\
1655 		_ctx->selected_sk = _selected_sk;			\
1656 		_ctx->no_reuseport = _no_reuseport;			\
1657 		migrate_enable();					\
1658 		_all_pass || _selected_sk ? SK_PASS : SK_DROP;		\
1659 	 })
1660 
bpf_sk_lookup_run_v4(const struct net * net,int protocol,const __be32 saddr,const __be16 sport,const __be32 daddr,const u16 dport,const int ifindex,struct sock ** psk)1661 static inline bool bpf_sk_lookup_run_v4(const struct net *net, int protocol,
1662 					const __be32 saddr, const __be16 sport,
1663 					const __be32 daddr, const u16 dport,
1664 					const int ifindex, struct sock **psk)
1665 {
1666 	struct bpf_prog_array *run_array;
1667 	struct sock *selected_sk = NULL;
1668 	bool no_reuseport = false;
1669 
1670 	rcu_read_lock();
1671 	run_array = rcu_dereference(net->bpf.run_array[NETNS_BPF_SK_LOOKUP]);
1672 	if (run_array) {
1673 		struct bpf_sk_lookup_kern ctx = {
1674 			.family		= AF_INET,
1675 			.protocol	= protocol,
1676 			.v4.saddr	= saddr,
1677 			.v4.daddr	= daddr,
1678 			.sport		= sport,
1679 			.dport		= dport,
1680 			.ingress_ifindex	= ifindex,
1681 		};
1682 		u32 act;
1683 
1684 		act = BPF_PROG_SK_LOOKUP_RUN_ARRAY(run_array, ctx, bpf_prog_run);
1685 		if (act == SK_PASS) {
1686 			selected_sk = ctx.selected_sk;
1687 			no_reuseport = ctx.no_reuseport;
1688 		} else {
1689 			selected_sk = ERR_PTR(-ECONNREFUSED);
1690 		}
1691 	}
1692 	rcu_read_unlock();
1693 	*psk = selected_sk;
1694 	return no_reuseport;
1695 }
1696 
1697 #if IS_ENABLED(CONFIG_IPV6)
bpf_sk_lookup_run_v6(const struct net * net,int protocol,const struct in6_addr * saddr,const __be16 sport,const struct in6_addr * daddr,const u16 dport,const int ifindex,struct sock ** psk)1698 static inline bool bpf_sk_lookup_run_v6(const struct net *net, int protocol,
1699 					const struct in6_addr *saddr,
1700 					const __be16 sport,
1701 					const struct in6_addr *daddr,
1702 					const u16 dport,
1703 					const int ifindex, struct sock **psk)
1704 {
1705 	struct bpf_prog_array *run_array;
1706 	struct sock *selected_sk = NULL;
1707 	bool no_reuseport = false;
1708 
1709 	rcu_read_lock();
1710 	run_array = rcu_dereference(net->bpf.run_array[NETNS_BPF_SK_LOOKUP]);
1711 	if (run_array) {
1712 		struct bpf_sk_lookup_kern ctx = {
1713 			.family		= AF_INET6,
1714 			.protocol	= protocol,
1715 			.v6.saddr	= saddr,
1716 			.v6.daddr	= daddr,
1717 			.sport		= sport,
1718 			.dport		= dport,
1719 			.ingress_ifindex	= ifindex,
1720 		};
1721 		u32 act;
1722 
1723 		act = BPF_PROG_SK_LOOKUP_RUN_ARRAY(run_array, ctx, bpf_prog_run);
1724 		if (act == SK_PASS) {
1725 			selected_sk = ctx.selected_sk;
1726 			no_reuseport = ctx.no_reuseport;
1727 		} else {
1728 			selected_sk = ERR_PTR(-ECONNREFUSED);
1729 		}
1730 	}
1731 	rcu_read_unlock();
1732 	*psk = selected_sk;
1733 	return no_reuseport;
1734 }
1735 #endif /* IS_ENABLED(CONFIG_IPV6) */
1736 
__bpf_xdp_redirect_map(struct bpf_map * map,u64 index,u64 flags,const u64 flag_mask,void * lookup_elem (struct bpf_map * map,u32 key))1737 static __always_inline long __bpf_xdp_redirect_map(struct bpf_map *map, u64 index,
1738 						   u64 flags, const u64 flag_mask,
1739 						   void *lookup_elem(struct bpf_map *map, u32 key))
1740 {
1741 	struct bpf_redirect_info *ri = bpf_net_ctx_get_ri();
1742 	const u64 action_mask = XDP_ABORTED | XDP_DROP | XDP_PASS | XDP_TX;
1743 
1744 	/* Lower bits of the flags are used as return code on lookup failure */
1745 	if (unlikely(flags & ~(action_mask | flag_mask)))
1746 		return XDP_ABORTED;
1747 
1748 	ri->tgt_value = lookup_elem(map, index);
1749 	if (unlikely(!ri->tgt_value) && !(flags & BPF_F_BROADCAST)) {
1750 		/* If the lookup fails we want to clear out the state in the
1751 		 * redirect_info struct completely, so that if an eBPF program
1752 		 * performs multiple lookups, the last one always takes
1753 		 * precedence.
1754 		 */
1755 		ri->map_id = INT_MAX; /* Valid map id idr range: [1,INT_MAX[ */
1756 		ri->map_type = BPF_MAP_TYPE_UNSPEC;
1757 		return flags & action_mask;
1758 	}
1759 
1760 	ri->tgt_index = index;
1761 	ri->map_id = map->id;
1762 	ri->map_type = map->map_type;
1763 
1764 	if (flags & BPF_F_BROADCAST) {
1765 		WRITE_ONCE(ri->map, map);
1766 		ri->flags = flags;
1767 	} else {
1768 		WRITE_ONCE(ri->map, NULL);
1769 		ri->flags = 0;
1770 	}
1771 
1772 	return XDP_REDIRECT;
1773 }
1774 
1775 #ifdef CONFIG_NET
1776 int __bpf_skb_load_bytes(const struct sk_buff *skb, u32 offset, void *to, u32 len);
1777 int __bpf_skb_store_bytes(struct sk_buff *skb, u32 offset, const void *from,
1778 			  u32 len, u64 flags);
1779 int __bpf_xdp_load_bytes(struct xdp_buff *xdp, u32 offset, void *buf, u32 len);
1780 int __bpf_xdp_store_bytes(struct xdp_buff *xdp, u32 offset, void *buf, u32 len);
1781 void *bpf_xdp_pointer(struct xdp_buff *xdp, u32 offset, u32 len);
1782 void bpf_xdp_copy_buf(struct xdp_buff *xdp, unsigned long off,
1783 		      void *buf, unsigned long len, bool flush);
1784 void *bpf_skb_meta_pointer(struct sk_buff *skb, u32 offset);
1785 #else /* CONFIG_NET */
__bpf_skb_load_bytes(const struct sk_buff * skb,u32 offset,void * to,u32 len)1786 static inline int __bpf_skb_load_bytes(const struct sk_buff *skb, u32 offset,
1787 				       void *to, u32 len)
1788 {
1789 	return -EOPNOTSUPP;
1790 }
1791 
__bpf_skb_store_bytes(struct sk_buff * skb,u32 offset,const void * from,u32 len,u64 flags)1792 static inline int __bpf_skb_store_bytes(struct sk_buff *skb, u32 offset,
1793 					const void *from, u32 len, u64 flags)
1794 {
1795 	return -EOPNOTSUPP;
1796 }
1797 
__bpf_xdp_load_bytes(struct xdp_buff * xdp,u32 offset,void * buf,u32 len)1798 static inline int __bpf_xdp_load_bytes(struct xdp_buff *xdp, u32 offset,
1799 				       void *buf, u32 len)
1800 {
1801 	return -EOPNOTSUPP;
1802 }
1803 
__bpf_xdp_store_bytes(struct xdp_buff * xdp,u32 offset,void * buf,u32 len)1804 static inline int __bpf_xdp_store_bytes(struct xdp_buff *xdp, u32 offset,
1805 					void *buf, u32 len)
1806 {
1807 	return -EOPNOTSUPP;
1808 }
1809 
bpf_xdp_pointer(struct xdp_buff * xdp,u32 offset,u32 len)1810 static inline void *bpf_xdp_pointer(struct xdp_buff *xdp, u32 offset, u32 len)
1811 {
1812 	return NULL;
1813 }
1814 
bpf_xdp_copy_buf(struct xdp_buff * xdp,unsigned long off,void * buf,unsigned long len,bool flush)1815 static inline void bpf_xdp_copy_buf(struct xdp_buff *xdp, unsigned long off, void *buf,
1816 				    unsigned long len, bool flush)
1817 {
1818 }
1819 
bpf_skb_meta_pointer(struct sk_buff * skb,u32 offset)1820 static inline void *bpf_skb_meta_pointer(struct sk_buff *skb, u32 offset)
1821 {
1822 	return ERR_PTR(-EOPNOTSUPP);
1823 }
1824 #endif /* CONFIG_NET */
1825 
1826 #endif /* __LINUX_FILTER_H__ */
1827