Merge tag 'linux-watchdog-5.6-rc1' of git://www.linux-watchdog.org/linux-watchdog
[linux-2.6-microblaze.git] / include / linux / filter.h
1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  * Linux Socket Filter Data Structures
4  */
5 #ifndef __LINUX_FILTER_H__
6 #define __LINUX_FILTER_H__
7
8 #include <stdarg.h>
9
10 #include <linux/atomic.h>
11 #include <linux/refcount.h>
12 #include <linux/compat.h>
13 #include <linux/skbuff.h>
14 #include <linux/linkage.h>
15 #include <linux/printk.h>
16 #include <linux/workqueue.h>
17 #include <linux/sched.h>
18 #include <linux/capability.h>
19 #include <linux/cryptohash.h>
20 #include <linux/set_memory.h>
21 #include <linux/kallsyms.h>
22 #include <linux/if_vlan.h>
23 #include <linux/vmalloc.h>
24
25 #include <net/sch_generic.h>
26
27 #include <asm/byteorder.h>
28 #include <uapi/linux/filter.h>
29 #include <uapi/linux/bpf.h>
30
31 struct sk_buff;
32 struct sock;
33 struct seccomp_data;
34 struct bpf_prog_aux;
35 struct xdp_rxq_info;
36 struct xdp_buff;
37 struct sock_reuseport;
38 struct ctl_table;
39 struct ctl_table_header;
40
41 /* ArgX, context and stack frame pointer register positions. Note,
42  * Arg1, Arg2, Arg3, etc are used as argument mappings of function
43  * calls in BPF_CALL instruction.
44  */
45 #define BPF_REG_ARG1    BPF_REG_1
46 #define BPF_REG_ARG2    BPF_REG_2
47 #define BPF_REG_ARG3    BPF_REG_3
48 #define BPF_REG_ARG4    BPF_REG_4
49 #define BPF_REG_ARG5    BPF_REG_5
50 #define BPF_REG_CTX     BPF_REG_6
51 #define BPF_REG_FP      BPF_REG_10
52
53 /* Additional register mappings for converted user programs. */
54 #define BPF_REG_A       BPF_REG_0
55 #define BPF_REG_X       BPF_REG_7
56 #define BPF_REG_TMP     BPF_REG_2       /* scratch reg */
57 #define BPF_REG_D       BPF_REG_8       /* data, callee-saved */
58 #define BPF_REG_H       BPF_REG_9       /* hlen, callee-saved */
59
60 /* Kernel hidden auxiliary/helper register. */
61 #define BPF_REG_AX              MAX_BPF_REG
62 #define MAX_BPF_EXT_REG         (MAX_BPF_REG + 1)
63 #define MAX_BPF_JIT_REG         MAX_BPF_EXT_REG
64
65 /* unused opcode to mark special call to bpf_tail_call() helper */
66 #define BPF_TAIL_CALL   0xf0
67
68 /* unused opcode to mark special load instruction. Same as BPF_ABS */
69 #define BPF_PROBE_MEM   0x20
70
71 /* unused opcode to mark call to interpreter with arguments */
72 #define BPF_CALL_ARGS   0xe0
73
74 /* As per nm, we expose JITed images as text (code) section for
75  * kallsyms. That way, tools like perf can find it to match
76  * addresses.
77  */
78 #define BPF_SYM_ELF_TYPE        't'
79
80 /* BPF program can access up to 512 bytes of stack space. */
81 #define MAX_BPF_STACK   512
82
83 /* Helper macros for filter block array initializers. */
84
85 /* ALU ops on registers, bpf_add|sub|...: dst_reg += src_reg */
86
87 #define BPF_ALU64_REG(OP, DST, SRC)                             \
88         ((struct bpf_insn) {                                    \
89                 .code  = BPF_ALU64 | BPF_OP(OP) | BPF_X,        \
90                 .dst_reg = DST,                                 \
91                 .src_reg = SRC,                                 \
92                 .off   = 0,                                     \
93                 .imm   = 0 })
94
95 #define BPF_ALU32_REG(OP, DST, SRC)                             \
96         ((struct bpf_insn) {                                    \
97                 .code  = BPF_ALU | BPF_OP(OP) | BPF_X,          \
98                 .dst_reg = DST,                                 \
99                 .src_reg = SRC,                                 \
100                 .off   = 0,                                     \
101                 .imm   = 0 })
102
103 /* ALU ops on immediates, bpf_add|sub|...: dst_reg += imm32 */
104
105 #define BPF_ALU64_IMM(OP, DST, IMM)                             \
106         ((struct bpf_insn) {                                    \
107                 .code  = BPF_ALU64 | BPF_OP(OP) | BPF_K,        \
108                 .dst_reg = DST,                                 \
109                 .src_reg = 0,                                   \
110                 .off   = 0,                                     \
111                 .imm   = IMM })
112
113 #define BPF_ALU32_IMM(OP, DST, IMM)                             \
114         ((struct bpf_insn) {                                    \
115                 .code  = BPF_ALU | BPF_OP(OP) | BPF_K,          \
116                 .dst_reg = DST,                                 \
117                 .src_reg = 0,                                   \
118                 .off   = 0,                                     \
119                 .imm   = IMM })
120
121 /* Endianess conversion, cpu_to_{l,b}e(), {l,b}e_to_cpu() */
122
123 #define BPF_ENDIAN(TYPE, DST, LEN)                              \
124         ((struct bpf_insn) {                                    \
125                 .code  = BPF_ALU | BPF_END | BPF_SRC(TYPE),     \
126                 .dst_reg = DST,                                 \
127                 .src_reg = 0,                                   \
128                 .off   = 0,                                     \
129                 .imm   = LEN })
130
131 /* Short form of mov, dst_reg = src_reg */
132
133 #define BPF_MOV64_REG(DST, SRC)                                 \
134         ((struct bpf_insn) {                                    \
135                 .code  = BPF_ALU64 | BPF_MOV | BPF_X,           \
136                 .dst_reg = DST,                                 \
137                 .src_reg = SRC,                                 \
138                 .off   = 0,                                     \
139                 .imm   = 0 })
140
141 #define BPF_MOV32_REG(DST, SRC)                                 \
142         ((struct bpf_insn) {                                    \
143                 .code  = BPF_ALU | BPF_MOV | BPF_X,             \
144                 .dst_reg = DST,                                 \
145                 .src_reg = SRC,                                 \
146                 .off   = 0,                                     \
147                 .imm   = 0 })
148
149 /* Short form of mov, dst_reg = imm32 */
150
151 #define BPF_MOV64_IMM(DST, IMM)                                 \
152         ((struct bpf_insn) {                                    \
153                 .code  = BPF_ALU64 | BPF_MOV | BPF_K,           \
154                 .dst_reg = DST,                                 \
155                 .src_reg = 0,                                   \
156                 .off   = 0,                                     \
157                 .imm   = IMM })
158
159 #define BPF_MOV32_IMM(DST, IMM)                                 \
160         ((struct bpf_insn) {                                    \
161                 .code  = BPF_ALU | BPF_MOV | BPF_K,             \
162                 .dst_reg = DST,                                 \
163                 .src_reg = 0,                                   \
164                 .off   = 0,                                     \
165                 .imm   = IMM })
166
167 /* Special form of mov32, used for doing explicit zero extension on dst. */
168 #define BPF_ZEXT_REG(DST)                                       \
169         ((struct bpf_insn) {                                    \
170                 .code  = BPF_ALU | BPF_MOV | BPF_X,             \
171                 .dst_reg = DST,                                 \
172                 .src_reg = DST,                                 \
173                 .off   = 0,                                     \
174                 .imm   = 1 })
175
176 static inline bool insn_is_zext(const struct bpf_insn *insn)
177 {
178         return insn->code == (BPF_ALU | BPF_MOV | BPF_X) && insn->imm == 1;
179 }
180
181 /* BPF_LD_IMM64 macro encodes single 'load 64-bit immediate' insn */
182 #define BPF_LD_IMM64(DST, IMM)                                  \
183         BPF_LD_IMM64_RAW(DST, 0, IMM)
184
185 #define BPF_LD_IMM64_RAW(DST, SRC, IMM)                         \
186         ((struct bpf_insn) {                                    \
187                 .code  = BPF_LD | BPF_DW | BPF_IMM,             \
188                 .dst_reg = DST,                                 \
189                 .src_reg = SRC,                                 \
190                 .off   = 0,                                     \
191                 .imm   = (__u32) (IMM) }),                      \
192         ((struct bpf_insn) {                                    \
193                 .code  = 0, /* zero is reserved opcode */       \
194                 .dst_reg = 0,                                   \
195                 .src_reg = 0,                                   \
196                 .off   = 0,                                     \
197                 .imm   = ((__u64) (IMM)) >> 32 })
198
199 /* pseudo BPF_LD_IMM64 insn used to refer to process-local map_fd */
200 #define BPF_LD_MAP_FD(DST, MAP_FD)                              \
201         BPF_LD_IMM64_RAW(DST, BPF_PSEUDO_MAP_FD, MAP_FD)
202
203 /* Short form of mov based on type, BPF_X: dst_reg = src_reg, BPF_K: dst_reg = imm32 */
204
205 #define BPF_MOV64_RAW(TYPE, DST, SRC, IMM)                      \
206         ((struct bpf_insn) {                                    \
207                 .code  = BPF_ALU64 | BPF_MOV | BPF_SRC(TYPE),   \
208                 .dst_reg = DST,                                 \
209                 .src_reg = SRC,                                 \
210                 .off   = 0,                                     \
211                 .imm   = IMM })
212
213 #define BPF_MOV32_RAW(TYPE, DST, SRC, IMM)                      \
214         ((struct bpf_insn) {                                    \
215                 .code  = BPF_ALU | BPF_MOV | BPF_SRC(TYPE),     \
216                 .dst_reg = DST,                                 \
217                 .src_reg = SRC,                                 \
218                 .off   = 0,                                     \
219                 .imm   = IMM })
220
221 /* Direct packet access, R0 = *(uint *) (skb->data + imm32) */
222
223 #define BPF_LD_ABS(SIZE, IMM)                                   \
224         ((struct bpf_insn) {                                    \
225                 .code  = BPF_LD | BPF_SIZE(SIZE) | BPF_ABS,     \
226                 .dst_reg = 0,                                   \
227                 .src_reg = 0,                                   \
228                 .off   = 0,                                     \
229                 .imm   = IMM })
230
231 /* Indirect packet access, R0 = *(uint *) (skb->data + src_reg + imm32) */
232
233 #define BPF_LD_IND(SIZE, SRC, IMM)                              \
234         ((struct bpf_insn) {                                    \
235                 .code  = BPF_LD | BPF_SIZE(SIZE) | BPF_IND,     \
236                 .dst_reg = 0,                                   \
237                 .src_reg = SRC,                                 \
238                 .off   = 0,                                     \
239                 .imm   = IMM })
240
241 /* Memory load, dst_reg = *(uint *) (src_reg + off16) */
242
243 #define BPF_LDX_MEM(SIZE, DST, SRC, OFF)                        \
244         ((struct bpf_insn) {                                    \
245                 .code  = BPF_LDX | BPF_SIZE(SIZE) | BPF_MEM,    \
246                 .dst_reg = DST,                                 \
247                 .src_reg = SRC,                                 \
248                 .off   = OFF,                                   \
249                 .imm   = 0 })
250
251 /* Memory store, *(uint *) (dst_reg + off16) = src_reg */
252
253 #define BPF_STX_MEM(SIZE, DST, SRC, OFF)                        \
254         ((struct bpf_insn) {                                    \
255                 .code  = BPF_STX | BPF_SIZE(SIZE) | BPF_MEM,    \
256                 .dst_reg = DST,                                 \
257                 .src_reg = SRC,                                 \
258                 .off   = OFF,                                   \
259                 .imm   = 0 })
260
261 /* Atomic memory add, *(uint *)(dst_reg + off16) += src_reg */
262
263 #define BPF_STX_XADD(SIZE, DST, SRC, OFF)                       \
264         ((struct bpf_insn) {                                    \
265                 .code  = BPF_STX | BPF_SIZE(SIZE) | BPF_XADD,   \
266                 .dst_reg = DST,                                 \
267                 .src_reg = SRC,                                 \
268                 .off   = OFF,                                   \
269                 .imm   = 0 })
270
271 /* Memory store, *(uint *) (dst_reg + off16) = imm32 */
272
273 #define BPF_ST_MEM(SIZE, DST, OFF, IMM)                         \
274         ((struct bpf_insn) {                                    \
275                 .code  = BPF_ST | BPF_SIZE(SIZE) | BPF_MEM,     \
276                 .dst_reg = DST,                                 \
277                 .src_reg = 0,                                   \
278                 .off   = OFF,                                   \
279                 .imm   = IMM })
280
281 /* Conditional jumps against registers, if (dst_reg 'op' src_reg) goto pc + off16 */
282
283 #define BPF_JMP_REG(OP, DST, SRC, OFF)                          \
284         ((struct bpf_insn) {                                    \
285                 .code  = BPF_JMP | BPF_OP(OP) | BPF_X,          \
286                 .dst_reg = DST,                                 \
287                 .src_reg = SRC,                                 \
288                 .off   = OFF,                                   \
289                 .imm   = 0 })
290
291 /* Conditional jumps against immediates, if (dst_reg 'op' imm32) goto pc + off16 */
292
293 #define BPF_JMP_IMM(OP, DST, IMM, OFF)                          \
294         ((struct bpf_insn) {                                    \
295                 .code  = BPF_JMP | BPF_OP(OP) | BPF_K,          \
296                 .dst_reg = DST,                                 \
297                 .src_reg = 0,                                   \
298                 .off   = OFF,                                   \
299                 .imm   = IMM })
300
301 /* Like BPF_JMP_REG, but with 32-bit wide operands for comparison. */
302
303 #define BPF_JMP32_REG(OP, DST, SRC, OFF)                        \
304         ((struct bpf_insn) {                                    \
305                 .code  = BPF_JMP32 | BPF_OP(OP) | BPF_X,        \
306                 .dst_reg = DST,                                 \
307                 .src_reg = SRC,                                 \
308                 .off   = OFF,                                   \
309                 .imm   = 0 })
310
311 /* Like BPF_JMP_IMM, but with 32-bit wide operands for comparison. */
312
313 #define BPF_JMP32_IMM(OP, DST, IMM, OFF)                        \
314         ((struct bpf_insn) {                                    \
315                 .code  = BPF_JMP32 | BPF_OP(OP) | BPF_K,        \
316                 .dst_reg = DST,                                 \
317                 .src_reg = 0,                                   \
318                 .off   = OFF,                                   \
319                 .imm   = IMM })
320
321 /* Unconditional jumps, goto pc + off16 */
322
323 #define BPF_JMP_A(OFF)                                          \
324         ((struct bpf_insn) {                                    \
325                 .code  = BPF_JMP | BPF_JA,                      \
326                 .dst_reg = 0,                                   \
327                 .src_reg = 0,                                   \
328                 .off   = OFF,                                   \
329                 .imm   = 0 })
330
331 /* Relative call */
332
333 #define BPF_CALL_REL(TGT)                                       \
334         ((struct bpf_insn) {                                    \
335                 .code  = BPF_JMP | BPF_CALL,                    \
336                 .dst_reg = 0,                                   \
337                 .src_reg = BPF_PSEUDO_CALL,                     \
338                 .off   = 0,                                     \
339                 .imm   = TGT })
340
341 /* Function call */
342
343 #define BPF_CAST_CALL(x)                                        \
344                 ((u64 (*)(u64, u64, u64, u64, u64))(x))
345
346 #define BPF_EMIT_CALL(FUNC)                                     \
347         ((struct bpf_insn) {                                    \
348                 .code  = BPF_JMP | BPF_CALL,                    \
349                 .dst_reg = 0,                                   \
350                 .src_reg = 0,                                   \
351                 .off   = 0,                                     \
352                 .imm   = ((FUNC) - __bpf_call_base) })
353
354 /* Raw code statement block */
355
356 #define BPF_RAW_INSN(CODE, DST, SRC, OFF, IMM)                  \
357         ((struct bpf_insn) {                                    \
358                 .code  = CODE,                                  \
359                 .dst_reg = DST,                                 \
360                 .src_reg = SRC,                                 \
361                 .off   = OFF,                                   \
362                 .imm   = IMM })
363
364 /* Program exit */
365
366 #define BPF_EXIT_INSN()                                         \
367         ((struct bpf_insn) {                                    \
368                 .code  = BPF_JMP | BPF_EXIT,                    \
369                 .dst_reg = 0,                                   \
370                 .src_reg = 0,                                   \
371                 .off   = 0,                                     \
372                 .imm   = 0 })
373
374 /* Internal classic blocks for direct assignment */
375
376 #define __BPF_STMT(CODE, K)                                     \
377         ((struct sock_filter) BPF_STMT(CODE, K))
378
379 #define __BPF_JUMP(CODE, K, JT, JF)                             \
380         ((struct sock_filter) BPF_JUMP(CODE, K, JT, JF))
381
382 #define bytes_to_bpf_size(bytes)                                \
383 ({                                                              \
384         int bpf_size = -EINVAL;                                 \
385                                                                 \
386         if (bytes == sizeof(u8))                                \
387                 bpf_size = BPF_B;                               \
388         else if (bytes == sizeof(u16))                          \
389                 bpf_size = BPF_H;                               \
390         else if (bytes == sizeof(u32))                          \
391                 bpf_size = BPF_W;                               \
392         else if (bytes == sizeof(u64))                          \
393                 bpf_size = BPF_DW;                              \
394                                                                 \
395         bpf_size;                                               \
396 })
397
398 #define bpf_size_to_bytes(bpf_size)                             \
399 ({                                                              \
400         int bytes = -EINVAL;                                    \
401                                                                 \
402         if (bpf_size == BPF_B)                                  \
403                 bytes = sizeof(u8);                             \
404         else if (bpf_size == BPF_H)                             \
405                 bytes = sizeof(u16);                            \
406         else if (bpf_size == BPF_W)                             \
407                 bytes = sizeof(u32);                            \
408         else if (bpf_size == BPF_DW)                            \
409                 bytes = sizeof(u64);                            \
410                                                                 \
411         bytes;                                                  \
412 })
413
414 #define BPF_SIZEOF(type)                                        \
415         ({                                                      \
416                 const int __size = bytes_to_bpf_size(sizeof(type)); \
417                 BUILD_BUG_ON(__size < 0);                       \
418                 __size;                                         \
419         })
420
421 #define BPF_FIELD_SIZEOF(type, field)                           \
422         ({                                                      \
423                 const int __size = bytes_to_bpf_size(sizeof_field(type, field)); \
424                 BUILD_BUG_ON(__size < 0);                       \
425                 __size;                                         \
426         })
427
428 #define BPF_LDST_BYTES(insn)                                    \
429         ({                                                      \
430                 const int __size = bpf_size_to_bytes(BPF_SIZE((insn)->code)); \
431                 WARN_ON(__size < 0);                            \
432                 __size;                                         \
433         })
434
435 #define __BPF_MAP_0(m, v, ...) v
436 #define __BPF_MAP_1(m, v, t, a, ...) m(t, a)
437 #define __BPF_MAP_2(m, v, t, a, ...) m(t, a), __BPF_MAP_1(m, v, __VA_ARGS__)
438 #define __BPF_MAP_3(m, v, t, a, ...) m(t, a), __BPF_MAP_2(m, v, __VA_ARGS__)
439 #define __BPF_MAP_4(m, v, t, a, ...) m(t, a), __BPF_MAP_3(m, v, __VA_ARGS__)
440 #define __BPF_MAP_5(m, v, t, a, ...) m(t, a), __BPF_MAP_4(m, v, __VA_ARGS__)
441
442 #define __BPF_REG_0(...) __BPF_PAD(5)
443 #define __BPF_REG_1(...) __BPF_MAP(1, __VA_ARGS__), __BPF_PAD(4)
444 #define __BPF_REG_2(...) __BPF_MAP(2, __VA_ARGS__), __BPF_PAD(3)
445 #define __BPF_REG_3(...) __BPF_MAP(3, __VA_ARGS__), __BPF_PAD(2)
446 #define __BPF_REG_4(...) __BPF_MAP(4, __VA_ARGS__), __BPF_PAD(1)
447 #define __BPF_REG_5(...) __BPF_MAP(5, __VA_ARGS__)
448
449 #define __BPF_MAP(n, ...) __BPF_MAP_##n(__VA_ARGS__)
450 #define __BPF_REG(n, ...) __BPF_REG_##n(__VA_ARGS__)
451
452 #define __BPF_CAST(t, a)                                                       \
453         (__force t)                                                            \
454         (__force                                                               \
455          typeof(__builtin_choose_expr(sizeof(t) == sizeof(unsigned long),      \
456                                       (unsigned long)0, (t)0))) a
457 #define __BPF_V void
458 #define __BPF_N
459
460 #define __BPF_DECL_ARGS(t, a) t   a
461 #define __BPF_DECL_REGS(t, a) u64 a
462
463 #define __BPF_PAD(n)                                                           \
464         __BPF_MAP(n, __BPF_DECL_ARGS, __BPF_N, u64, __ur_1, u64, __ur_2,       \
465                   u64, __ur_3, u64, __ur_4, u64, __ur_5)
466
467 #define BPF_CALL_x(x, name, ...)                                               \
468         static __always_inline                                                 \
469         u64 ____##name(__BPF_MAP(x, __BPF_DECL_ARGS, __BPF_V, __VA_ARGS__));   \
470         typedef u64 (*btf_##name)(__BPF_MAP(x, __BPF_DECL_ARGS, __BPF_V, __VA_ARGS__)); \
471         u64 name(__BPF_REG(x, __BPF_DECL_REGS, __BPF_N, __VA_ARGS__));         \
472         u64 name(__BPF_REG(x, __BPF_DECL_REGS, __BPF_N, __VA_ARGS__))          \
473         {                                                                      \
474                 return ((btf_##name)____##name)(__BPF_MAP(x,__BPF_CAST,__BPF_N,__VA_ARGS__));\
475         }                                                                      \
476         static __always_inline                                                 \
477         u64 ____##name(__BPF_MAP(x, __BPF_DECL_ARGS, __BPF_V, __VA_ARGS__))
478
479 #define BPF_CALL_0(name, ...)   BPF_CALL_x(0, name, __VA_ARGS__)
480 #define BPF_CALL_1(name, ...)   BPF_CALL_x(1, name, __VA_ARGS__)
481 #define BPF_CALL_2(name, ...)   BPF_CALL_x(2, name, __VA_ARGS__)
482 #define BPF_CALL_3(name, ...)   BPF_CALL_x(3, name, __VA_ARGS__)
483 #define BPF_CALL_4(name, ...)   BPF_CALL_x(4, name, __VA_ARGS__)
484 #define BPF_CALL_5(name, ...)   BPF_CALL_x(5, name, __VA_ARGS__)
485
486 #define bpf_ctx_range(TYPE, MEMBER)                                             \
487         offsetof(TYPE, MEMBER) ... offsetofend(TYPE, MEMBER) - 1
488 #define bpf_ctx_range_till(TYPE, MEMBER1, MEMBER2)                              \
489         offsetof(TYPE, MEMBER1) ... offsetofend(TYPE, MEMBER2) - 1
490 #if BITS_PER_LONG == 64
491 # define bpf_ctx_range_ptr(TYPE, MEMBER)                                        \
492         offsetof(TYPE, MEMBER) ... offsetofend(TYPE, MEMBER) - 1
493 #else
494 # define bpf_ctx_range_ptr(TYPE, MEMBER)                                        \
495         offsetof(TYPE, MEMBER) ... offsetof(TYPE, MEMBER) + 8 - 1
496 #endif /* BITS_PER_LONG == 64 */
497
498 #define bpf_target_off(TYPE, MEMBER, SIZE, PTR_SIZE)                            \
499         ({                                                                      \
500                 BUILD_BUG_ON(sizeof_field(TYPE, MEMBER) != (SIZE));             \
501                 *(PTR_SIZE) = (SIZE);                                           \
502                 offsetof(TYPE, MEMBER);                                         \
503         })
504
505 #ifdef CONFIG_COMPAT
506 /* A struct sock_filter is architecture independent. */
507 struct compat_sock_fprog {
508         u16             len;
509         compat_uptr_t   filter; /* struct sock_filter * */
510 };
511 #endif
512
513 struct sock_fprog_kern {
514         u16                     len;
515         struct sock_filter      *filter;
516 };
517
518 /* Some arches need doubleword alignment for their instructions and/or data */
519 #define BPF_IMAGE_ALIGNMENT 8
520
521 struct bpf_binary_header {
522         u32 pages;
523         u8 image[] __aligned(BPF_IMAGE_ALIGNMENT);
524 };
525
526 struct bpf_prog {
527         u16                     pages;          /* Number of allocated pages */
528         u16                     jited:1,        /* Is our filter JIT'ed? */
529                                 jit_requested:1,/* archs need to JIT the prog */
530                                 gpl_compatible:1, /* Is filter GPL compatible? */
531                                 cb_access:1,    /* Is control block accessed? */
532                                 dst_needed:1,   /* Do we need dst entry? */
533                                 blinded:1,      /* Was blinded */
534                                 is_func:1,      /* program is a bpf function */
535                                 kprobe_override:1, /* Do we override a kprobe? */
536                                 has_callchain_buf:1, /* callchain buffer allocated? */
537                                 enforce_expected_attach_type:1; /* Enforce expected_attach_type checking at attach time */
538         enum bpf_prog_type      type;           /* Type of BPF program */
539         enum bpf_attach_type    expected_attach_type; /* For some prog types */
540         u32                     len;            /* Number of filter blocks */
541         u32                     jited_len;      /* Size of jited insns in bytes */
542         u8                      tag[BPF_TAG_SIZE];
543         struct bpf_prog_aux     *aux;           /* Auxiliary fields */
544         struct sock_fprog_kern  *orig_prog;     /* Original BPF program */
545         unsigned int            (*bpf_func)(const void *ctx,
546                                             const struct bpf_insn *insn);
547         /* Instructions for interpreter */
548         union {
549                 struct sock_filter      insns[0];
550                 struct bpf_insn         insnsi[0];
551         };
552 };
553
554 struct sk_filter {
555         refcount_t      refcnt;
556         struct rcu_head rcu;
557         struct bpf_prog *prog;
558 };
559
560 DECLARE_STATIC_KEY_FALSE(bpf_stats_enabled_key);
561
562 #define __BPF_PROG_RUN(prog, ctx, dfunc)        ({                      \
563         u32 ret;                                                        \
564         cant_sleep();                                                   \
565         if (static_branch_unlikely(&bpf_stats_enabled_key)) {           \
566                 struct bpf_prog_stats *stats;                           \
567                 u64 start = sched_clock();                              \
568                 ret = dfunc(ctx, (prog)->insnsi, (prog)->bpf_func);     \
569                 stats = this_cpu_ptr(prog->aux->stats);                 \
570                 u64_stats_update_begin(&stats->syncp);                  \
571                 stats->cnt++;                                           \
572                 stats->nsecs += sched_clock() - start;                  \
573                 u64_stats_update_end(&stats->syncp);                    \
574         } else {                                                        \
575                 ret = dfunc(ctx, (prog)->insnsi, (prog)->bpf_func);     \
576         }                                                               \
577         ret; })
578
579 #define BPF_PROG_RUN(prog, ctx) __BPF_PROG_RUN(prog, ctx,               \
580                                                bpf_dispatcher_nopfunc)
581
582 #define BPF_SKB_CB_LEN QDISC_CB_PRIV_LEN
583
584 struct bpf_skb_data_end {
585         struct qdisc_skb_cb qdisc_cb;
586         void *data_meta;
587         void *data_end;
588 };
589
590 struct bpf_redirect_info {
591         u32 flags;
592         u32 tgt_index;
593         void *tgt_value;
594         struct bpf_map *map;
595         u32 kern_flags;
596 };
597
598 DECLARE_PER_CPU(struct bpf_redirect_info, bpf_redirect_info);
599
600 /* flags for bpf_redirect_info kern_flags */
601 #define BPF_RI_F_RF_NO_DIRECT   BIT(0)  /* no napi_direct on return_frame */
602
603 /* Compute the linear packet data range [data, data_end) which
604  * will be accessed by various program types (cls_bpf, act_bpf,
605  * lwt, ...). Subsystems allowing direct data access must (!)
606  * ensure that cb[] area can be written to when BPF program is
607  * invoked (otherwise cb[] save/restore is necessary).
608  */
609 static inline void bpf_compute_data_pointers(struct sk_buff *skb)
610 {
611         struct bpf_skb_data_end *cb = (struct bpf_skb_data_end *)skb->cb;
612
613         BUILD_BUG_ON(sizeof(*cb) > sizeof_field(struct sk_buff, cb));
614         cb->data_meta = skb->data - skb_metadata_len(skb);
615         cb->data_end  = skb->data + skb_headlen(skb);
616 }
617
618 /* Similar to bpf_compute_data_pointers(), except that save orginal
619  * data in cb->data and cb->meta_data for restore.
620  */
621 static inline void bpf_compute_and_save_data_end(
622         struct sk_buff *skb, void **saved_data_end)
623 {
624         struct bpf_skb_data_end *cb = (struct bpf_skb_data_end *)skb->cb;
625
626         *saved_data_end = cb->data_end;
627         cb->data_end  = skb->data + skb_headlen(skb);
628 }
629
630 /* Restore data saved by bpf_compute_data_pointers(). */
631 static inline void bpf_restore_data_end(
632         struct sk_buff *skb, void *saved_data_end)
633 {
634         struct bpf_skb_data_end *cb = (struct bpf_skb_data_end *)skb->cb;
635
636         cb->data_end = saved_data_end;
637 }
638
639 static inline u8 *bpf_skb_cb(struct sk_buff *skb)
640 {
641         /* eBPF programs may read/write skb->cb[] area to transfer meta
642          * data between tail calls. Since this also needs to work with
643          * tc, that scratch memory is mapped to qdisc_skb_cb's data area.
644          *
645          * In some socket filter cases, the cb unfortunately needs to be
646          * saved/restored so that protocol specific skb->cb[] data won't
647          * be lost. In any case, due to unpriviledged eBPF programs
648          * attached to sockets, we need to clear the bpf_skb_cb() area
649          * to not leak previous contents to user space.
650          */
651         BUILD_BUG_ON(sizeof_field(struct __sk_buff, cb) != BPF_SKB_CB_LEN);
652         BUILD_BUG_ON(sizeof_field(struct __sk_buff, cb) !=
653                      sizeof_field(struct qdisc_skb_cb, data));
654
655         return qdisc_skb_cb(skb)->data;
656 }
657
658 static inline u32 __bpf_prog_run_save_cb(const struct bpf_prog *prog,
659                                          struct sk_buff *skb)
660 {
661         u8 *cb_data = bpf_skb_cb(skb);
662         u8 cb_saved[BPF_SKB_CB_LEN];
663         u32 res;
664
665         if (unlikely(prog->cb_access)) {
666                 memcpy(cb_saved, cb_data, sizeof(cb_saved));
667                 memset(cb_data, 0, sizeof(cb_saved));
668         }
669
670         res = BPF_PROG_RUN(prog, skb);
671
672         if (unlikely(prog->cb_access))
673                 memcpy(cb_data, cb_saved, sizeof(cb_saved));
674
675         return res;
676 }
677
678 static inline u32 bpf_prog_run_save_cb(const struct bpf_prog *prog,
679                                        struct sk_buff *skb)
680 {
681         u32 res;
682
683         preempt_disable();
684         res = __bpf_prog_run_save_cb(prog, skb);
685         preempt_enable();
686         return res;
687 }
688
689 static inline u32 bpf_prog_run_clear_cb(const struct bpf_prog *prog,
690                                         struct sk_buff *skb)
691 {
692         u8 *cb_data = bpf_skb_cb(skb);
693         u32 res;
694
695         if (unlikely(prog->cb_access))
696                 memset(cb_data, 0, BPF_SKB_CB_LEN);
697
698         preempt_disable();
699         res = BPF_PROG_RUN(prog, skb);
700         preempt_enable();
701         return res;
702 }
703
704 DECLARE_BPF_DISPATCHER(bpf_dispatcher_xdp)
705
706 static __always_inline u32 bpf_prog_run_xdp(const struct bpf_prog *prog,
707                                             struct xdp_buff *xdp)
708 {
709         /* Caller needs to hold rcu_read_lock() (!), otherwise program
710          * can be released while still running, or map elements could be
711          * freed early while still having concurrent users. XDP fastpath
712          * already takes rcu_read_lock() when fetching the program, so
713          * it's not necessary here anymore.
714          */
715         return __BPF_PROG_RUN(prog, xdp,
716                               BPF_DISPATCHER_FUNC(bpf_dispatcher_xdp));
717 }
718
719 void bpf_prog_change_xdp(struct bpf_prog *prev_prog, struct bpf_prog *prog);
720
721 static inline u32 bpf_prog_insn_size(const struct bpf_prog *prog)
722 {
723         return prog->len * sizeof(struct bpf_insn);
724 }
725
726 static inline u32 bpf_prog_tag_scratch_size(const struct bpf_prog *prog)
727 {
728         return round_up(bpf_prog_insn_size(prog) +
729                         sizeof(__be64) + 1, SHA_MESSAGE_BYTES);
730 }
731
732 static inline unsigned int bpf_prog_size(unsigned int proglen)
733 {
734         return max(sizeof(struct bpf_prog),
735                    offsetof(struct bpf_prog, insns[proglen]));
736 }
737
738 static inline bool bpf_prog_was_classic(const struct bpf_prog *prog)
739 {
740         /* When classic BPF programs have been loaded and the arch
741          * does not have a classic BPF JIT (anymore), they have been
742          * converted via bpf_migrate_filter() to eBPF and thus always
743          * have an unspec program type.
744          */
745         return prog->type == BPF_PROG_TYPE_UNSPEC;
746 }
747
748 static inline u32 bpf_ctx_off_adjust_machine(u32 size)
749 {
750         const u32 size_machine = sizeof(unsigned long);
751
752         if (size > size_machine && size % size_machine == 0)
753                 size = size_machine;
754
755         return size;
756 }
757
758 static inline bool
759 bpf_ctx_narrow_access_ok(u32 off, u32 size, u32 size_default)
760 {
761         return size <= size_default && (size & (size - 1)) == 0;
762 }
763
764 static inline u8
765 bpf_ctx_narrow_access_offset(u32 off, u32 size, u32 size_default)
766 {
767         u8 access_off = off & (size_default - 1);
768
769 #ifdef __LITTLE_ENDIAN
770         return access_off;
771 #else
772         return size_default - (access_off + size);
773 #endif
774 }
775
776 #define bpf_ctx_wide_access_ok(off, size, type, field)                  \
777         (size == sizeof(__u64) &&                                       \
778         off >= offsetof(type, field) &&                                 \
779         off + sizeof(__u64) <= offsetofend(type, field) &&              \
780         off % sizeof(__u64) == 0)
781
782 #define bpf_classic_proglen(fprog) (fprog->len * sizeof(fprog->filter[0]))
783
784 static inline void bpf_prog_lock_ro(struct bpf_prog *fp)
785 {
786 #ifndef CONFIG_BPF_JIT_ALWAYS_ON
787         if (!fp->jited) {
788                 set_vm_flush_reset_perms(fp);
789                 set_memory_ro((unsigned long)fp, fp->pages);
790         }
791 #endif
792 }
793
794 static inline void bpf_jit_binary_lock_ro(struct bpf_binary_header *hdr)
795 {
796         set_vm_flush_reset_perms(hdr);
797         set_memory_ro((unsigned long)hdr, hdr->pages);
798         set_memory_x((unsigned long)hdr, hdr->pages);
799 }
800
801 static inline struct bpf_binary_header *
802 bpf_jit_binary_hdr(const struct bpf_prog *fp)
803 {
804         unsigned long real_start = (unsigned long)fp->bpf_func;
805         unsigned long addr = real_start & PAGE_MASK;
806
807         return (void *)addr;
808 }
809
810 int sk_filter_trim_cap(struct sock *sk, struct sk_buff *skb, unsigned int cap);
811 static inline int sk_filter(struct sock *sk, struct sk_buff *skb)
812 {
813         return sk_filter_trim_cap(sk, skb, 1);
814 }
815
816 struct bpf_prog *bpf_prog_select_runtime(struct bpf_prog *fp, int *err);
817 void bpf_prog_free(struct bpf_prog *fp);
818
819 bool bpf_opcode_in_insntable(u8 code);
820
821 void bpf_prog_free_linfo(struct bpf_prog *prog);
822 void bpf_prog_fill_jited_linfo(struct bpf_prog *prog,
823                                const u32 *insn_to_jit_off);
824 int bpf_prog_alloc_jited_linfo(struct bpf_prog *prog);
825 void bpf_prog_free_jited_linfo(struct bpf_prog *prog);
826 void bpf_prog_free_unused_jited_linfo(struct bpf_prog *prog);
827
828 struct bpf_prog *bpf_prog_alloc(unsigned int size, gfp_t gfp_extra_flags);
829 struct bpf_prog *bpf_prog_alloc_no_stats(unsigned int size, gfp_t gfp_extra_flags);
830 struct bpf_prog *bpf_prog_realloc(struct bpf_prog *fp_old, unsigned int size,
831                                   gfp_t gfp_extra_flags);
832 void __bpf_prog_free(struct bpf_prog *fp);
833
834 static inline void bpf_prog_unlock_free(struct bpf_prog *fp)
835 {
836         __bpf_prog_free(fp);
837 }
838
839 typedef int (*bpf_aux_classic_check_t)(struct sock_filter *filter,
840                                        unsigned int flen);
841
842 int bpf_prog_create(struct bpf_prog **pfp, struct sock_fprog_kern *fprog);
843 int bpf_prog_create_from_user(struct bpf_prog **pfp, struct sock_fprog *fprog,
844                               bpf_aux_classic_check_t trans, bool save_orig);
845 void bpf_prog_destroy(struct bpf_prog *fp);
846 const struct bpf_func_proto *
847 bpf_base_func_proto(enum bpf_func_id func_id);
848
849 int sk_attach_filter(struct sock_fprog *fprog, struct sock *sk);
850 int sk_attach_bpf(u32 ufd, struct sock *sk);
851 int sk_reuseport_attach_filter(struct sock_fprog *fprog, struct sock *sk);
852 int sk_reuseport_attach_bpf(u32 ufd, struct sock *sk);
853 void sk_reuseport_prog_free(struct bpf_prog *prog);
854 int sk_detach_filter(struct sock *sk);
855 int sk_get_filter(struct sock *sk, struct sock_filter __user *filter,
856                   unsigned int len);
857
858 bool sk_filter_charge(struct sock *sk, struct sk_filter *fp);
859 void sk_filter_uncharge(struct sock *sk, struct sk_filter *fp);
860
861 u64 __bpf_call_base(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5);
862 #define __bpf_call_base_args \
863         ((u64 (*)(u64, u64, u64, u64, u64, const struct bpf_insn *)) \
864          __bpf_call_base)
865
866 struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog);
867 void bpf_jit_compile(struct bpf_prog *prog);
868 bool bpf_jit_needs_zext(void);
869 bool bpf_helper_changes_pkt_data(void *func);
870
871 static inline bool bpf_dump_raw_ok(void)
872 {
873         /* Reconstruction of call-sites is dependent on kallsyms,
874          * thus make dump the same restriction.
875          */
876         return kallsyms_show_value() == 1;
877 }
878
879 struct bpf_prog *bpf_patch_insn_single(struct bpf_prog *prog, u32 off,
880                                        const struct bpf_insn *patch, u32 len);
881 int bpf_remove_insns(struct bpf_prog *prog, u32 off, u32 cnt);
882
883 void bpf_clear_redirect_map(struct bpf_map *map);
884
885 static inline bool xdp_return_frame_no_direct(void)
886 {
887         struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
888
889         return ri->kern_flags & BPF_RI_F_RF_NO_DIRECT;
890 }
891
892 static inline void xdp_set_return_frame_no_direct(void)
893 {
894         struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
895
896         ri->kern_flags |= BPF_RI_F_RF_NO_DIRECT;
897 }
898
899 static inline void xdp_clear_return_frame_no_direct(void)
900 {
901         struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
902
903         ri->kern_flags &= ~BPF_RI_F_RF_NO_DIRECT;
904 }
905
906 static inline int xdp_ok_fwd_dev(const struct net_device *fwd,
907                                  unsigned int pktlen)
908 {
909         unsigned int len;
910
911         if (unlikely(!(fwd->flags & IFF_UP)))
912                 return -ENETDOWN;
913
914         len = fwd->mtu + fwd->hard_header_len + VLAN_HLEN;
915         if (pktlen > len)
916                 return -EMSGSIZE;
917
918         return 0;
919 }
920
921 /* The pair of xdp_do_redirect and xdp_do_flush MUST be called in the
922  * same cpu context. Further for best results no more than a single map
923  * for the do_redirect/do_flush pair should be used. This limitation is
924  * because we only track one map and force a flush when the map changes.
925  * This does not appear to be a real limitation for existing software.
926  */
927 int xdp_do_generic_redirect(struct net_device *dev, struct sk_buff *skb,
928                             struct xdp_buff *xdp, struct bpf_prog *prog);
929 int xdp_do_redirect(struct net_device *dev,
930                     struct xdp_buff *xdp,
931                     struct bpf_prog *prog);
932 void xdp_do_flush(void);
933
934 /* The xdp_do_flush_map() helper has been renamed to drop the _map suffix, as
935  * it is no longer only flushing maps. Keep this define for compatibility
936  * until all drivers are updated - do not use xdp_do_flush_map() in new code!
937  */
938 #define xdp_do_flush_map xdp_do_flush
939
940 void bpf_warn_invalid_xdp_action(u32 act);
941
942 #ifdef CONFIG_INET
943 struct sock *bpf_run_sk_reuseport(struct sock_reuseport *reuse, struct sock *sk,
944                                   struct bpf_prog *prog, struct sk_buff *skb,
945                                   u32 hash);
946 #else
947 static inline struct sock *
948 bpf_run_sk_reuseport(struct sock_reuseport *reuse, struct sock *sk,
949                      struct bpf_prog *prog, struct sk_buff *skb,
950                      u32 hash)
951 {
952         return NULL;
953 }
954 #endif
955
956 #ifdef CONFIG_BPF_JIT
957 extern int bpf_jit_enable;
958 extern int bpf_jit_harden;
959 extern int bpf_jit_kallsyms;
960 extern long bpf_jit_limit;
961
962 typedef void (*bpf_jit_fill_hole_t)(void *area, unsigned int size);
963
964 struct bpf_binary_header *
965 bpf_jit_binary_alloc(unsigned int proglen, u8 **image_ptr,
966                      unsigned int alignment,
967                      bpf_jit_fill_hole_t bpf_fill_ill_insns);
968 void bpf_jit_binary_free(struct bpf_binary_header *hdr);
969 u64 bpf_jit_alloc_exec_limit(void);
970 void *bpf_jit_alloc_exec(unsigned long size);
971 void bpf_jit_free_exec(void *addr);
972 void bpf_jit_free(struct bpf_prog *fp);
973
974 int bpf_jit_add_poke_descriptor(struct bpf_prog *prog,
975                                 struct bpf_jit_poke_descriptor *poke);
976
977 int bpf_jit_get_func_addr(const struct bpf_prog *prog,
978                           const struct bpf_insn *insn, bool extra_pass,
979                           u64 *func_addr, bool *func_addr_fixed);
980
981 struct bpf_prog *bpf_jit_blind_constants(struct bpf_prog *fp);
982 void bpf_jit_prog_release_other(struct bpf_prog *fp, struct bpf_prog *fp_other);
983
984 static inline void bpf_jit_dump(unsigned int flen, unsigned int proglen,
985                                 u32 pass, void *image)
986 {
987         pr_err("flen=%u proglen=%u pass=%u image=%pK from=%s pid=%d\n", flen,
988                proglen, pass, image, current->comm, task_pid_nr(current));
989
990         if (image)
991                 print_hex_dump(KERN_ERR, "JIT code: ", DUMP_PREFIX_OFFSET,
992                                16, 1, image, proglen, false);
993 }
994
995 static inline bool bpf_jit_is_ebpf(void)
996 {
997 # ifdef CONFIG_HAVE_EBPF_JIT
998         return true;
999 # else
1000         return false;
1001 # endif
1002 }
1003
1004 static inline bool ebpf_jit_enabled(void)
1005 {
1006         return bpf_jit_enable && bpf_jit_is_ebpf();
1007 }
1008
1009 static inline bool bpf_prog_ebpf_jited(const struct bpf_prog *fp)
1010 {
1011         return fp->jited && bpf_jit_is_ebpf();
1012 }
1013
1014 static inline bool bpf_jit_blinding_enabled(struct bpf_prog *prog)
1015 {
1016         /* These are the prerequisites, should someone ever have the
1017          * idea to call blinding outside of them, we make sure to
1018          * bail out.
1019          */
1020         if (!bpf_jit_is_ebpf())
1021                 return false;
1022         if (!prog->jit_requested)
1023                 return false;
1024         if (!bpf_jit_harden)
1025                 return false;
1026         if (bpf_jit_harden == 1 && capable(CAP_SYS_ADMIN))
1027                 return false;
1028
1029         return true;
1030 }
1031
1032 static inline bool bpf_jit_kallsyms_enabled(void)
1033 {
1034         /* There are a couple of corner cases where kallsyms should
1035          * not be enabled f.e. on hardening.
1036          */
1037         if (bpf_jit_harden)
1038                 return false;
1039         if (!bpf_jit_kallsyms)
1040                 return false;
1041         if (bpf_jit_kallsyms == 1)
1042                 return true;
1043
1044         return false;
1045 }
1046
1047 const char *__bpf_address_lookup(unsigned long addr, unsigned long *size,
1048                                  unsigned long *off, char *sym);
1049 bool is_bpf_text_address(unsigned long addr);
1050 int bpf_get_kallsym(unsigned int symnum, unsigned long *value, char *type,
1051                     char *sym);
1052
1053 static inline const char *
1054 bpf_address_lookup(unsigned long addr, unsigned long *size,
1055                    unsigned long *off, char **modname, char *sym)
1056 {
1057         const char *ret = __bpf_address_lookup(addr, size, off, sym);
1058
1059         if (ret && modname)
1060                 *modname = NULL;
1061         return ret;
1062 }
1063
1064 void bpf_prog_kallsyms_add(struct bpf_prog *fp);
1065 void bpf_prog_kallsyms_del(struct bpf_prog *fp);
1066 void bpf_get_prog_name(const struct bpf_prog *prog, char *sym);
1067
1068 #else /* CONFIG_BPF_JIT */
1069
1070 static inline bool ebpf_jit_enabled(void)
1071 {
1072         return false;
1073 }
1074
1075 static inline bool bpf_jit_blinding_enabled(struct bpf_prog *prog)
1076 {
1077         return false;
1078 }
1079
1080 static inline bool bpf_prog_ebpf_jited(const struct bpf_prog *fp)
1081 {
1082         return false;
1083 }
1084
1085 static inline int
1086 bpf_jit_add_poke_descriptor(struct bpf_prog *prog,
1087                             struct bpf_jit_poke_descriptor *poke)
1088 {
1089         return -ENOTSUPP;
1090 }
1091
1092 static inline void bpf_jit_free(struct bpf_prog *fp)
1093 {
1094         bpf_prog_unlock_free(fp);
1095 }
1096
1097 static inline bool bpf_jit_kallsyms_enabled(void)
1098 {
1099         return false;
1100 }
1101
1102 static inline const char *
1103 __bpf_address_lookup(unsigned long addr, unsigned long *size,
1104                      unsigned long *off, char *sym)
1105 {
1106         return NULL;
1107 }
1108
1109 static inline bool is_bpf_text_address(unsigned long addr)
1110 {
1111         return false;
1112 }
1113
1114 static inline int bpf_get_kallsym(unsigned int symnum, unsigned long *value,
1115                                   char *type, char *sym)
1116 {
1117         return -ERANGE;
1118 }
1119
1120 static inline const char *
1121 bpf_address_lookup(unsigned long addr, unsigned long *size,
1122                    unsigned long *off, char **modname, char *sym)
1123 {
1124         return NULL;
1125 }
1126
1127 static inline void bpf_prog_kallsyms_add(struct bpf_prog *fp)
1128 {
1129 }
1130
1131 static inline void bpf_prog_kallsyms_del(struct bpf_prog *fp)
1132 {
1133 }
1134
1135 static inline void bpf_get_prog_name(const struct bpf_prog *prog, char *sym)
1136 {
1137         sym[0] = '\0';
1138 }
1139
1140 #endif /* CONFIG_BPF_JIT */
1141
1142 void bpf_prog_kallsyms_del_all(struct bpf_prog *fp);
1143
1144 #define BPF_ANC         BIT(15)
1145
1146 static inline bool bpf_needs_clear_a(const struct sock_filter *first)
1147 {
1148         switch (first->code) {
1149         case BPF_RET | BPF_K:
1150         case BPF_LD | BPF_W | BPF_LEN:
1151                 return false;
1152
1153         case BPF_LD | BPF_W | BPF_ABS:
1154         case BPF_LD | BPF_H | BPF_ABS:
1155         case BPF_LD | BPF_B | BPF_ABS:
1156                 if (first->k == SKF_AD_OFF + SKF_AD_ALU_XOR_X)
1157                         return true;
1158                 return false;
1159
1160         default:
1161                 return true;
1162         }
1163 }
1164
1165 static inline u16 bpf_anc_helper(const struct sock_filter *ftest)
1166 {
1167         BUG_ON(ftest->code & BPF_ANC);
1168
1169         switch (ftest->code) {
1170         case BPF_LD | BPF_W | BPF_ABS:
1171         case BPF_LD | BPF_H | BPF_ABS:
1172         case BPF_LD | BPF_B | BPF_ABS:
1173 #define BPF_ANCILLARY(CODE)     case SKF_AD_OFF + SKF_AD_##CODE:        \
1174                                 return BPF_ANC | SKF_AD_##CODE
1175                 switch (ftest->k) {
1176                 BPF_ANCILLARY(PROTOCOL);
1177                 BPF_ANCILLARY(PKTTYPE);
1178                 BPF_ANCILLARY(IFINDEX);
1179                 BPF_ANCILLARY(NLATTR);
1180                 BPF_ANCILLARY(NLATTR_NEST);
1181                 BPF_ANCILLARY(MARK);
1182                 BPF_ANCILLARY(QUEUE);
1183                 BPF_ANCILLARY(HATYPE);
1184                 BPF_ANCILLARY(RXHASH);
1185                 BPF_ANCILLARY(CPU);
1186                 BPF_ANCILLARY(ALU_XOR_X);
1187                 BPF_ANCILLARY(VLAN_TAG);
1188                 BPF_ANCILLARY(VLAN_TAG_PRESENT);
1189                 BPF_ANCILLARY(PAY_OFFSET);
1190                 BPF_ANCILLARY(RANDOM);
1191                 BPF_ANCILLARY(VLAN_TPID);
1192                 }
1193                 /* Fallthrough. */
1194         default:
1195                 return ftest->code;
1196         }
1197 }
1198
1199 void *bpf_internal_load_pointer_neg_helper(const struct sk_buff *skb,
1200                                            int k, unsigned int size);
1201
1202 static inline void *bpf_load_pointer(const struct sk_buff *skb, int k,
1203                                      unsigned int size, void *buffer)
1204 {
1205         if (k >= 0)
1206                 return skb_header_pointer(skb, k, size, buffer);
1207
1208         return bpf_internal_load_pointer_neg_helper(skb, k, size);
1209 }
1210
1211 static inline int bpf_tell_extensions(void)
1212 {
1213         return SKF_AD_MAX;
1214 }
1215
1216 struct bpf_sock_addr_kern {
1217         struct sock *sk;
1218         struct sockaddr *uaddr;
1219         /* Temporary "register" to make indirect stores to nested structures
1220          * defined above. We need three registers to make such a store, but
1221          * only two (src and dst) are available at convert_ctx_access time
1222          */
1223         u64 tmp_reg;
1224         void *t_ctx;    /* Attach type specific context. */
1225 };
1226
1227 struct bpf_sock_ops_kern {
1228         struct  sock *sk;
1229         u32     op;
1230         union {
1231                 u32 args[4];
1232                 u32 reply;
1233                 u32 replylong[4];
1234         };
1235         u32     is_fullsock;
1236         u64     temp;                   /* temp and everything after is not
1237                                          * initialized to 0 before calling
1238                                          * the BPF program. New fields that
1239                                          * should be initialized to 0 should
1240                                          * be inserted before temp.
1241                                          * temp is scratch storage used by
1242                                          * sock_ops_convert_ctx_access
1243                                          * as temporary storage of a register.
1244                                          */
1245 };
1246
1247 struct bpf_sysctl_kern {
1248         struct ctl_table_header *head;
1249         struct ctl_table *table;
1250         void *cur_val;
1251         size_t cur_len;
1252         void *new_val;
1253         size_t new_len;
1254         int new_updated;
1255         int write;
1256         loff_t *ppos;
1257         /* Temporary "register" for indirect stores to ppos. */
1258         u64 tmp_reg;
1259 };
1260
1261 struct bpf_sockopt_kern {
1262         struct sock     *sk;
1263         u8              *optval;
1264         u8              *optval_end;
1265         s32             level;
1266         s32             optname;
1267         s32             optlen;
1268         s32             retval;
1269 };
1270
1271 #endif /* __LINUX_FILTER_H__ */