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
  24 #include <net/sch_generic.h>
  25
  26 #include <uapi/linux/filter.h>
  27 #include <uapi/linux/bpf.h>
  28
  29 struct sk_buff;
  30 struct sock;
  31 struct seccomp_data;
  32 struct bpf_prog_aux;
  33 struct xdp_rxq_info;
  34 struct xdp_buff;
  35 struct sock_reuseport;
  36
  37 /* ArgX, context and stack frame pointer register positions. Note,
  38  * Arg1, Arg2, Arg3, etc are used as argument mappings of function
  39  * calls in BPF_CALL instruction.
  40  */
  41 #define BPF_REG_ARG1    BPF_REG_1
  42 #define BPF_REG_ARG2    BPF_REG_2
  43 #define BPF_REG_ARG3    BPF_REG_3
  44 #define BPF_REG_ARG4    BPF_REG_4
  45 #define BPF_REG_ARG5    BPF_REG_5
  46 #define BPF_REG_CTX     BPF_REG_6
  47 #define BPF_REG_FP      BPF_REG_10
  48
  49 /* Additional register mappings for converted user programs. */
  50 #define BPF_REG_A       BPF_REG_0
  51 #define BPF_REG_X       BPF_REG_7
  52 #define BPF_REG_TMP     BPF_REG_2       /* scratch reg */
  53 #define BPF_REG_D       BPF_REG_8       /* data, callee-saved */
  54 #define BPF_REG_H       BPF_REG_9       /* hlen, callee-saved */
  55
  56 /* Kernel hidden auxiliary/helper register. */
  57 #define BPF_REG_AX              MAX_BPF_REG
  58 #define MAX_BPF_EXT_REG         (MAX_BPF_REG + 1)
  59 #define MAX_BPF_JIT_REG         MAX_BPF_EXT_REG
  60
  61 /* unused opcode to mark special call to bpf_tail_call() helper */
  62 #define BPF_TAIL_CALL   0xf0
  63
  64 /* unused opcode to mark call to interpreter with arguments */
  65 #define BPF_CALL_ARGS   0xe0
  66
  67 /* unused opcode to mark speculation barrier for mitigating
  68  * Speculative Store Bypass
  69  */
  70 #define BPF_NOSPEC      0xc0
  71
  72 /* As per nm, we expose JITed images as text (code) section for
  73  * kallsyms. That way, tools like perf can find it to match
  74  * addresses.
  75  */
  76 #define BPF_SYM_ELF_TYPE        't'
  77
  78 /* BPF program can access up to 512 bytes of stack space. */
  79 #define MAX_BPF_STACK   512
  80
  81 /* Helper macros for filter block array initializers. */
  82
  83 /* ALU ops on registers, bpf_add|sub|...: dst_reg += src_reg */
  84
  85 #define BPF_ALU_REG(CLASS, OP, DST, SRC)                        \
  86         ((struct bpf_insn) {                                    \
  87                 .code  = CLASS | BPF_OP(OP) | BPF_X,            \
  88                 .dst_reg = DST,                                 \
  89                 .src_reg = SRC,                                 \
  90                 .off   = 0,                                     \
  91                 .imm   = 0 })
  92
  93 #define BPF_ALU64_REG(OP, DST, SRC)                             \
  94         ((struct bpf_insn) {                                    \
  95                 .code  = BPF_ALU64 | BPF_OP(OP) | BPF_X,        \
  96                 .dst_reg = DST,                                 \
  97                 .src_reg = SRC,                                 \
  98                 .off   = 0,                                     \
  99                 .imm   = 0 })
 100
 101 #define BPF_ALU32_REG(OP, DST, SRC)                             \
 102         ((struct bpf_insn) {                                    \
 103                 .code  = BPF_ALU | BPF_OP(OP) | BPF_X,          \
 104                 .dst_reg = DST,                                 \
 105                 .src_reg = SRC,                                 \
 106                 .off   = 0,                                     \
 107                 .imm   = 0 })
 108
 109 /* ALU ops on immediates, bpf_add|sub|...: dst_reg += imm32 */
 110
 111 #define BPF_ALU64_IMM(OP, DST, IMM)                             \
 112         ((struct bpf_insn) {                                    \
 113                 .code  = BPF_ALU64 | BPF_OP(OP) | BPF_K,        \
 114                 .dst_reg = DST,                                 \
 115                 .src_reg = 0,                                   \
 116                 .off   = 0,                                     \
 117                 .imm   = IMM })
 118
 119 #define BPF_ALU32_IMM(OP, DST, IMM)                             \
 120         ((struct bpf_insn) {                                    \
 121                 .code  = BPF_ALU | BPF_OP(OP) | BPF_K,          \
 122                 .dst_reg = DST,                                 \
 123                 .src_reg = 0,                                   \
 124                 .off   = 0,                                     \
 125                 .imm   = IMM })
 126
 127 /* Endianess conversion, cpu_to_{l,b}e(), {l,b}e_to_cpu() */
 128
 129 #define BPF_ENDIAN(TYPE, DST, LEN)                              \
 130         ((struct bpf_insn) {                                    \
 131                 .code  = BPF_ALU | BPF_END | BPF_SRC(TYPE),     \
 132                 .dst_reg = DST,                                 \
 133                 .src_reg = 0,                                   \
 134                 .off   = 0,                                     \
 135                 .imm   = LEN })
 136
 137 /* Short form of mov, dst_reg = src_reg */
 138
 139 #define BPF_MOV_REG(CLASS, DST, SRC)                            \
 140         ((struct bpf_insn) {                                    \
 141                 .code  = CLASS | BPF_MOV | BPF_X,               \
 142                 .dst_reg = DST,                                 \
 143                 .src_reg = SRC,                                 \
 144                 .off   = 0,                                     \
 145                 .imm   = 0 })
 146
 147 #define BPF_MOV64_REG(DST, SRC)                                 \
 148         ((struct bpf_insn) {                                    \
 149                 .code  = BPF_ALU64 | BPF_MOV | BPF_X,           \
 150                 .dst_reg = DST,                                 \
 151                 .src_reg = SRC,                                 \
 152                 .off   = 0,                                     \
 153                 .imm   = 0 })
 154
 155 #define BPF_MOV32_REG(DST, SRC)                                 \
 156         ((struct bpf_insn) {                                    \
 157                 .code  = BPF_ALU | BPF_MOV | BPF_X,             \
 158                 .dst_reg = DST,                                 \
 159                 .src_reg = SRC,                                 \
 160                 .off   = 0,                                     \
 161                 .imm   = 0 })
 162
 163 /* Short form of mov, dst_reg = imm32 */
 164
 165 #define BPF_MOV64_IMM(DST, IMM)                                 \
 166         ((struct bpf_insn) {                                    \
 167                 .code  = BPF_ALU64 | BPF_MOV | BPF_K,           \
 168                 .dst_reg = DST,                                 \
 169                 .src_reg = 0,                                   \
 170                 .off   = 0,                                     \
 171                 .imm   = IMM })
 172
 173 #define BPF_MOV32_IMM(DST, IMM)                                 \
 174         ((struct bpf_insn) {                                    \
 175                 .code  = BPF_ALU | BPF_MOV | BPF_K,             \
 176                 .dst_reg = DST,                                 \
 177                 .src_reg = 0,                                   \
 178                 .off   = 0,                                     \
 179                 .imm   = IMM })
 180
 181 #define BPF_RAW_REG(insn, DST, SRC)                             \
 182         ((struct bpf_insn) {                                    \
 183                 .code  = (insn).code,                           \
 184                 .dst_reg = DST,                                 \
 185                 .src_reg = SRC,                                 \
 186                 .off   = (insn).off,                            \
 187                 .imm   = (insn).imm })
 188
 189 /* BPF_LD_IMM64 macro encodes single 'load 64-bit immediate' insn */
 190 #define BPF_LD_IMM64(DST, IMM)                                  \
 191         BPF_LD_IMM64_RAW(DST, 0, IMM)
 192
 193 #define BPF_LD_IMM64_RAW(DST, SRC, IMM)                         \
 194         ((struct bpf_insn) {                                    \
 195                 .code  = BPF_LD | BPF_DW | BPF_IMM,             \
 196                 .dst_reg = DST,                                 \
 197                 .src_reg = SRC,                                 \
 198                 .off   = 0,                                     \
 199                 .imm   = (__u32) (IMM) }),                      \
 200         ((struct bpf_insn) {                                    \
 201                 .code  = 0, /* zero is reserved opcode */       \
 202                 .dst_reg = 0,                                   \
 203                 .src_reg = 0,                                   \
 204                 .off   = 0,                                     \
 205                 .imm   = ((__u64) (IMM)) >> 32 })
 206
 207 /* pseudo BPF_LD_IMM64 insn used to refer to process-local map_fd */
 208 #define BPF_LD_MAP_FD(DST, MAP_FD)                              \
 209         BPF_LD_IMM64_RAW(DST, BPF_PSEUDO_MAP_FD, MAP_FD)
 210
 211 /* Short form of mov based on type, BPF_X: dst_reg = src_reg, BPF_K: dst_reg = imm32 */
 212
 213 #define BPF_MOV64_RAW(TYPE, DST, SRC, IMM)                      \
 214         ((struct bpf_insn) {                                    \
 215                 .code  = BPF_ALU64 | BPF_MOV | BPF_SRC(TYPE),   \
 216                 .dst_reg = DST,                                 \
 217                 .src_reg = SRC,                                 \
 218                 .off   = 0,                                     \
 219                 .imm   = IMM })
 220
 221 #define BPF_MOV32_RAW(TYPE, DST, SRC, IMM)                      \
 222         ((struct bpf_insn) {                                    \
 223                 .code  = BPF_ALU | BPF_MOV | BPF_SRC(TYPE),     \
 224                 .dst_reg = DST,                                 \
 225                 .src_reg = SRC,                                 \
 226                 .off   = 0,                                     \
 227                 .imm   = IMM })
 228
 229 /* Direct packet access, R0 = *(uint *) (skb->data + imm32) */
 230
 231 #define BPF_LD_ABS(SIZE, IMM)                                   \
 232         ((struct bpf_insn) {                                    \
 233                 .code  = BPF_LD | BPF_SIZE(SIZE) | BPF_ABS,     \
 234                 .dst_reg = 0,                                   \
 235                 .src_reg = 0,                                   \
 236                 .off   = 0,                                     \
 237                 .imm   = IMM })
 238
 239 /* Indirect packet access, R0 = *(uint *) (skb->data + src_reg + imm32) */
 240
 241 #define BPF_LD_IND(SIZE, SRC, IMM)                              \
 242         ((struct bpf_insn) {                                    \
 243                 .code  = BPF_LD | BPF_SIZE(SIZE) | BPF_IND,     \
 244                 .dst_reg = 0,                                   \
 245                 .src_reg = SRC,                                 \
 246                 .off   = 0,                                     \
 247                 .imm   = IMM })
 248
 249 /* Memory load, dst_reg = *(uint *) (src_reg + off16) */
 250
 251 #define BPF_LDX_MEM(SIZE, DST, SRC, OFF)                        \
 252         ((struct bpf_insn) {                                    \
 253                 .code  = BPF_LDX | BPF_SIZE(SIZE) | BPF_MEM,    \
 254                 .dst_reg = DST,                                 \
 255                 .src_reg = SRC,                                 \
 256                 .off   = OFF,                                   \
 257                 .imm   = 0 })
 258
 259 /* Memory store, *(uint *) (dst_reg + off16) = src_reg */
 260
 261 #define BPF_STX_MEM(SIZE, DST, SRC, OFF)                        \
 262         ((struct bpf_insn) {                                    \
 263                 .code  = BPF_STX | BPF_SIZE(SIZE) | BPF_MEM,    \
 264                 .dst_reg = DST,                                 \
 265                 .src_reg = SRC,                                 \
 266                 .off   = OFF,                                   \
 267                 .imm   = 0 })
 268
 269 /* Atomic memory add, *(uint *)(dst_reg + off16) += src_reg */
 270
 271 #define BPF_STX_XADD(SIZE, DST, SRC, OFF)                       \
 272         ((struct bpf_insn) {                                    \
 273                 .code  = BPF_STX | BPF_SIZE(SIZE) | BPF_XADD,   \
 274                 .dst_reg = DST,                                 \
 275                 .src_reg = SRC,                                 \
 276                 .off   = OFF,                                   \
 277                 .imm   = 0 })
 278
 279 /* Memory store, *(uint *) (dst_reg + off16) = imm32 */
 280
 281 #define BPF_ST_MEM(SIZE, DST, OFF, IMM)                         \
 282         ((struct bpf_insn) {                                    \
 283                 .code  = BPF_ST | BPF_SIZE(SIZE) | BPF_MEM,     \
 284                 .dst_reg = DST,                                 \
 285                 .src_reg = 0,                                   \
 286                 .off   = OFF,                                   \
 287                 .imm   = IMM })
 288
 289 /* Conditional jumps against registers, if (dst_reg 'op' src_reg) goto pc + off16 */
 290
 291 #define BPF_JMP_REG(OP, DST, SRC, OFF)                          \
 292         ((struct bpf_insn) {                                    \
 293                 .code  = BPF_JMP | BPF_OP(OP) | BPF_X,          \
 294                 .dst_reg = DST,                                 \
 295                 .src_reg = SRC,                                 \
 296                 .off   = OFF,                                   \
 297                 .imm   = 0 })
 298
 299 /* Conditional jumps against immediates, if (dst_reg 'op' imm32) goto pc + off16 */
 300
 301 #define BPF_JMP_IMM(OP, DST, IMM, OFF)                          \
 302         ((struct bpf_insn) {                                    \
 303                 .code  = BPF_JMP | BPF_OP(OP) | BPF_K,          \
 304                 .dst_reg = DST,                                 \
 305                 .src_reg = 0,                                   \
 306                 .off   = OFF,                                   \
 307                 .imm   = IMM })
 308
 309 /* Unconditional jumps, goto pc + off16 */
 310
 311 #define BPF_JMP_A(OFF)                                          \
 312         ((struct bpf_insn) {                                    \
 313                 .code  = BPF_JMP | BPF_JA,                      \
 314                 .dst_reg = 0,                                   \
 315                 .src_reg = 0,                                   \
 316                 .off   = OFF,                                   \
 317                 .imm   = 0 })
 318
 319 /* Relative call */
 320
 321 #define BPF_CALL_REL(TGT)                                       \
 322         ((struct bpf_insn) {                                    \
 323                 .code  = BPF_JMP | BPF_CALL,                    \
 324                 .dst_reg = 0,                                   \
 325                 .src_reg = BPF_PSEUDO_CALL,                     \
 326                 .off   = 0,                                     \
 327                 .imm   = TGT })
 328
 329 /* Function call */
 330
 331 #define BPF_CAST_CALL(x)                                        \
 332                 ((u64 (*)(u64, u64, u64, u64, u64))(x))
 333
 334 #define BPF_EMIT_CALL(FUNC)                                     \
 335         ((struct bpf_insn) {                                    \
 336                 .code  = BPF_JMP | BPF_CALL,                    \
 337                 .dst_reg = 0,                                   \
 338                 .src_reg = 0,                                   \
 339                 .off   = 0,                                     \
 340                 .imm   = ((FUNC) - __bpf_call_base) })
 341
 342 /* Raw code statement block */
 343
 344 #define BPF_RAW_INSN(CODE, DST, SRC, OFF, IMM)                  \
 345         ((struct bpf_insn) {                                    \
 346                 .code  = CODE,                                  \
 347                 .dst_reg = DST,                                 \
 348                 .src_reg = SRC,                                 \
 349                 .off   = OFF,                                   \
 350                 .imm   = IMM })
 351
 352 /* Program exit */
 353
 354 #define BPF_EXIT_INSN()                                         \
 355         ((struct bpf_insn) {                                    \
 356                 .code  = BPF_JMP | BPF_EXIT,                    \
 357                 .dst_reg = 0,                                   \
 358                 .src_reg = 0,                                   \
 359                 .off   = 0,                                     \
 360                 .imm   = 0 })
 361
 362 /* Speculation barrier */
 363
 364 #define BPF_ST_NOSPEC()                                         \
 365         ((struct bpf_insn) {                                    \
 366                 .code  = BPF_ST | BPF_NOSPEC,                   \
 367                 .dst_reg = 0,                                   \
 368                 .src_reg = 0,                                   \
 369                 .off   = 0,                                     \
 370                 .imm   = 0 })
 371
 372 /* Internal classic blocks for direct assignment */
 373
 374 #define __BPF_STMT(CODE, K)                                     \
 375         ((struct sock_filter) BPF_STMT(CODE, K))
 376
 377 #define __BPF_JUMP(CODE, K, JT, JF)                             \
 378         ((struct sock_filter) BPF_JUMP(CODE, K, JT, JF))
 379
 380 #define bytes_to_bpf_size(bytes)                                \
 381 ({                                                              \
 382         int bpf_size = -EINVAL;                                 \
 383                                                                 \
 384         if (bytes == sizeof(u8))                                \
 385                 bpf_size = BPF_B;                               \
 386         else if (bytes == sizeof(u16))                          \
 387                 bpf_size = BPF_H;                               \
 388         else if (bytes == sizeof(u32))                          \
 389                 bpf_size = BPF_W;                               \
 390         else if (bytes == sizeof(u64))                          \
 391                 bpf_size = BPF_DW;                              \
 392                                                                 \
 393         bpf_size;                                               \
 394 })
 395
 396 #define bpf_size_to_bytes(bpf_size)                             \
 397 ({                                                              \
 398         int bytes = -EINVAL;                                    \
 399                                                                 \
 400         if (bpf_size == BPF_B)                                  \
 401                 bytes = sizeof(u8);                             \
 402         else if (bpf_size == BPF_H)                             \
 403                 bytes = sizeof(u16);                            \
 404         else if (bpf_size == BPF_W)                             \
 405                 bytes = sizeof(u32);                            \
 406         else if (bpf_size == BPF_DW)                            \
 407                 bytes = sizeof(u64);                            \
 408                                                                 \
 409         bytes;                                                  \
 410 })
 411
 412 #define BPF_SIZEOF(type)                                        \
 413         ({                                                      \
 414                 const int __size = bytes_to_bpf_size(sizeof(type)); \
 415                 BUILD_BUG_ON(__size < 0);                       \
 416                 __size;                                         \
 417         })
 418
 419 #define BPF_FIELD_SIZEOF(type, field)                           \
 420         ({                                                      \
 421                 const int __size = bytes_to_bpf_size(FIELD_SIZEOF(type, field)); \
 422                 BUILD_BUG_ON(__size < 0);                       \
 423                 __size;                                         \
 424         })
 425
 426 #define BPF_LDST_BYTES(insn)                                    \
 427         ({                                                      \
 428                 const int __size = bpf_size_to_bytes(BPF_SIZE((insn)->code)); \
 429                 WARN_ON(__size < 0);                            \
 430                 __size;                                         \
 431         })
 432
 433 #define __BPF_MAP_0(m, v, ...) v
 434 #define __BPF_MAP_1(m, v, t, a, ...) m(t, a)
 435 #define __BPF_MAP_2(m, v, t, a, ...) m(t, a), __BPF_MAP_1(m, v, __VA_ARGS__)
 436 #define __BPF_MAP_3(m, v, t, a, ...) m(t, a), __BPF_MAP_2(m, v, __VA_ARGS__)
 437 #define __BPF_MAP_4(m, v, t, a, ...) m(t, a), __BPF_MAP_3(m, v, __VA_ARGS__)
 438 #define __BPF_MAP_5(m, v, t, a, ...) m(t, a), __BPF_MAP_4(m, v, __VA_ARGS__)
 439
 440 #define __BPF_REG_0(...) __BPF_PAD(5)
 441 #define __BPF_REG_1(...) __BPF_MAP(1, __VA_ARGS__), __BPF_PAD(4)
 442 #define __BPF_REG_2(...) __BPF_MAP(2, __VA_ARGS__), __BPF_PAD(3)
 443 #define __BPF_REG_3(...) __BPF_MAP(3, __VA_ARGS__), __BPF_PAD(2)
 444 #define __BPF_REG_4(...) __BPF_MAP(4, __VA_ARGS__), __BPF_PAD(1)
 445 #define __BPF_REG_5(...) __BPF_MAP(5, __VA_ARGS__)
 446
 447 #define __BPF_MAP(n, ...) __BPF_MAP_##n(__VA_ARGS__)
 448 #define __BPF_REG(n, ...) __BPF_REG_##n(__VA_ARGS__)
 449
 450 #define __BPF_CAST(t, a)                                                       \
 451         (__force t)                                                            \
 452         (__force                                                               \
 453          typeof(__builtin_choose_expr(sizeof(t) == sizeof(unsigned long),      \
 454                                       (unsigned long)0, (t)0))) a
 455 #define __BPF_V void
 456 #define __BPF_N
 457
 458 #define __BPF_DECL_ARGS(t, a) t   a
 459 #define __BPF_DECL_REGS(t, a) u64 a
 460
 461 #define __BPF_PAD(n)                                                           \
 462         __BPF_MAP(n, __BPF_DECL_ARGS, __BPF_N, u64, __ur_1, u64, __ur_2,       \
 463                   u64, __ur_3, u64, __ur_4, u64, __ur_5)
 464
 465 #define BPF_CALL_x(x, name, ...)                                               \
 466         static __always_inline                                                 \
 467         u64 ____##name(__BPF_MAP(x, __BPF_DECL_ARGS, __BPF_V, __VA_ARGS__));   \
 468         u64 name(__BPF_REG(x, __BPF_DECL_REGS, __BPF_N, __VA_ARGS__));         \
 469         u64 name(__BPF_REG(x, __BPF_DECL_REGS, __BPF_N, __VA_ARGS__))          \
 470         {                                                                      \
 471                 return ____##name(__BPF_MAP(x,__BPF_CAST,__BPF_N,__VA_ARGS__));\
 472         }                                                                      \
 473         static __always_inline                                                 \
 474         u64 ____##name(__BPF_MAP(x, __BPF_DECL_ARGS, __BPF_V, __VA_ARGS__))
 475
 476 #define BPF_CALL_0(name, ...)   BPF_CALL_x(0, name, __VA_ARGS__)
 477 #define BPF_CALL_1(name, ...)   BPF_CALL_x(1, name, __VA_ARGS__)
 478 #define BPF_CALL_2(name, ...)   BPF_CALL_x(2, name, __VA_ARGS__)
 479 #define BPF_CALL_3(name, ...)   BPF_CALL_x(3, name, __VA_ARGS__)
 480 #define BPF_CALL_4(name, ...)   BPF_CALL_x(4, name, __VA_ARGS__)
 481 #define BPF_CALL_5(name, ...)   BPF_CALL_x(5, name, __VA_ARGS__)
 482
 483 #define bpf_ctx_range(TYPE, MEMBER)                                             \
 484         offsetof(TYPE, MEMBER) ... offsetofend(TYPE, MEMBER) - 1
 485 #define bpf_ctx_range_till(TYPE, MEMBER1, MEMBER2)                              \
 486         offsetof(TYPE, MEMBER1) ... offsetofend(TYPE, MEMBER2) - 1
 487
 488 #define bpf_target_off(TYPE, MEMBER, SIZE, PTR_SIZE)                            \
 489         ({                                                                      \
 490                 BUILD_BUG_ON(FIELD_SIZEOF(TYPE, MEMBER) != (SIZE));             \
 491                 *(PTR_SIZE) = (SIZE);                                           \
 492                 offsetof(TYPE, MEMBER);                                         \
 493         })
 494
 495 #ifdef CONFIG_COMPAT
 496 /* A struct sock_filter is architecture independent. */
 497 struct compat_sock_fprog {
 498         u16             len;
 499         compat_uptr_t   filter; /* struct sock_filter * */
 500 };
 501 #endif
 502
 503 struct sock_fprog_kern {
 504         u16                     len;
 505         struct sock_filter      *filter;
 506 };
 507
 508 struct bpf_binary_header {
 509         u32 pages;
 510         /* Some arches need word alignment for their instructions */
 511         u8 image[] __aligned(4);
 512 };
 513
 514 struct bpf_prog {
 515         u16                     pages;          /* Number of allocated pages */
 516         u16                     jited:1,        /* Is our filter JIT'ed? */
 517                                 jit_requested:1,/* archs need to JIT the prog */
 518                                 undo_set_mem:1, /* Passed set_memory_ro() checkpoint */
 519                                 gpl_compatible:1, /* Is filter GPL compatible? */
 520                                 cb_access:1,    /* Is control block accessed? */
 521                                 dst_needed:1,   /* Do we need dst entry? */
 522                                 blinded:1,      /* Was blinded */
 523                                 is_func:1,      /* program is a bpf function */
 524                                 kprobe_override:1, /* Do we override a kprobe? */
 525                                 has_callchain_buf:1; /* callchain buffer allocated? */
 526         enum bpf_prog_type      type;           /* Type of BPF program */
 527         enum bpf_attach_type    expected_attach_type; /* For some prog types */
 528         u32                     len;            /* Number of filter blocks */
 529         u32                     jited_len;      /* Size of jited insns in bytes */
 530         u8                      tag[BPF_TAG_SIZE];
 531         struct bpf_prog_aux     *aux;           /* Auxiliary fields */
 532         struct sock_fprog_kern  *orig_prog;     /* Original BPF program */
 533         unsigned int            (*bpf_func)(const void *ctx,
 534                                             const struct bpf_insn *insn);
 535         /* Instructions for interpreter */
 536         union {
 537                 struct sock_filter      insns[0];
 538                 struct bpf_insn         insnsi[0];
 539         };
 540 };
 541
 542 struct sk_filter {
 543         refcount_t      refcnt;
 544         struct rcu_head rcu;
 545         struct bpf_prog *prog;
 546 };
 547
 548 #define BPF_PROG_RUN(filter, ctx)  (*(filter)->bpf_func)(ctx, (filter)->insnsi)
 549
 550 #define BPF_SKB_CB_LEN QDISC_CB_PRIV_LEN
 551
 552 struct bpf_skb_data_end {
 553         struct qdisc_skb_cb qdisc_cb;
 554         void *data_meta;
 555         void *data_end;
 556 };
 557
 558 struct sk_msg_buff {
 559         void *data;
 560         void *data_end;
 561         __u32 apply_bytes;
 562         __u32 cork_bytes;
 563         int sg_copybreak;
 564         int sg_start;
 565         int sg_curr;
 566         int sg_end;
 567         struct scatterlist sg_data[MAX_SKB_FRAGS];
 568         bool sg_copy[MAX_SKB_FRAGS];
 569         __u32 flags;
 570         struct sock *sk_redir;
 571         struct sock *sk;
 572         struct sk_buff *skb;
 573         struct list_head list;
 574 };
 575
 576 struct bpf_redirect_info {
 577         u32 ifindex;
 578         u32 flags;
 579         struct bpf_map *map;
 580         struct bpf_map *map_to_flush;
 581         u32 kern_flags;
 582 };
 583
 584 DECLARE_PER_CPU(struct bpf_redirect_info, bpf_redirect_info);
 585
 586 /* flags for bpf_redirect_info kern_flags */
 587 #define BPF_RI_F_RF_NO_DIRECT   BIT(0)  /* no napi_direct on return_frame */
 588
 589 /* Compute the linear packet data range [data, data_end) which
 590  * will be accessed by various program types (cls_bpf, act_bpf,
 591  * lwt, ...). Subsystems allowing direct data access must (!)
 592  * ensure that cb[] area can be written to when BPF program is
 593  * invoked (otherwise cb[] save/restore is necessary).
 594  */
 595 static inline void bpf_compute_data_pointers(struct sk_buff *skb)
 596 {
 597         struct bpf_skb_data_end *cb = (struct bpf_skb_data_end *)skb->cb;
 598
 599         BUILD_BUG_ON(sizeof(*cb) > FIELD_SIZEOF(struct sk_buff, cb));
 600         cb->data_meta = skb->data - skb_metadata_len(skb);
 601         cb->data_end  = skb->data + skb_headlen(skb);
 602 }
 603
 604 static inline u8 *bpf_skb_cb(struct sk_buff *skb)
 605 {
 606         /* eBPF programs may read/write skb->cb[] area to transfer meta
 607          * data between tail calls. Since this also needs to work with
 608          * tc, that scratch memory is mapped to qdisc_skb_cb's data area.
 609          *
 610          * In some socket filter cases, the cb unfortunately needs to be
 611          * saved/restored so that protocol specific skb->cb[] data won't
 612          * be lost. In any case, due to unpriviledged eBPF programs
 613          * attached to sockets, we need to clear the bpf_skb_cb() area
 614          * to not leak previous contents to user space.
 615          */
 616         BUILD_BUG_ON(FIELD_SIZEOF(struct __sk_buff, cb) != BPF_SKB_CB_LEN);
 617         BUILD_BUG_ON(FIELD_SIZEOF(struct __sk_buff, cb) !=
 618                      FIELD_SIZEOF(struct qdisc_skb_cb, data));
 619
 620         return qdisc_skb_cb(skb)->data;
 621 }
 622
 623 static inline u32 bpf_prog_run_save_cb(const struct bpf_prog *prog,
 624                                        struct sk_buff *skb)
 625 {
 626         u8 *cb_data = bpf_skb_cb(skb);
 627         u8 cb_saved[BPF_SKB_CB_LEN];
 628         u32 res;
 629
 630         if (unlikely(prog->cb_access)) {
 631                 memcpy(cb_saved, cb_data, sizeof(cb_saved));
 632                 memset(cb_data, 0, sizeof(cb_saved));
 633         }
 634
 635         res = BPF_PROG_RUN(prog, skb);
 636
 637         if (unlikely(prog->cb_access))
 638                 memcpy(cb_data, cb_saved, sizeof(cb_saved));
 639
 640         return res;
 641 }
 642
 643 static inline u32 bpf_prog_run_clear_cb(const struct bpf_prog *prog,
 644                                         struct sk_buff *skb)
 645 {
 646         u8 *cb_data = bpf_skb_cb(skb);
 647
 648         if (unlikely(prog->cb_access))
 649                 memset(cb_data, 0, BPF_SKB_CB_LEN);
 650
 651         return BPF_PROG_RUN(prog, skb);
 652 }
 653
 654 static __always_inline u32 bpf_prog_run_xdp(const struct bpf_prog *prog,
 655                                             struct xdp_buff *xdp)
 656 {
 657         /* Caller needs to hold rcu_read_lock() (!), otherwise program
 658          * can be released while still running, or map elements could be
 659          * freed early while still having concurrent users. XDP fastpath
 660          * already takes rcu_read_lock() when fetching the program, so
 661          * it's not necessary here anymore.
 662          */
 663         return BPF_PROG_RUN(prog, xdp);
 664 }
 665
 666 static inline u32 bpf_prog_insn_size(const struct bpf_prog *prog)
 667 {
 668         return prog->len * sizeof(struct bpf_insn);
 669 }
 670
 671 static inline u32 bpf_prog_tag_scratch_size(const struct bpf_prog *prog)
 672 {
 673         return round_up(bpf_prog_insn_size(prog) +
 674                         sizeof(__be64) + 1, SHA_MESSAGE_BYTES);
 675 }
 676
 677 static inline unsigned int bpf_prog_size(unsigned int proglen)
 678 {
 679         return max(sizeof(struct bpf_prog),
 680                    offsetof(struct bpf_prog, insns[proglen]));
 681 }
 682
 683 static inline bool bpf_prog_was_classic(const struct bpf_prog *prog)
 684 {
 685         /* When classic BPF programs have been loaded and the arch
 686          * does not have a classic BPF JIT (anymore), they have been
 687          * converted via bpf_migrate_filter() to eBPF and thus always
 688          * have an unspec program type.
 689          */
 690         return prog->type == BPF_PROG_TYPE_UNSPEC;
 691 }
 692
 693 static inline u32 bpf_ctx_off_adjust_machine(u32 size)
 694 {
 695         const u32 size_machine = sizeof(unsigned long);
 696
 697         if (size > size_machine && size % size_machine == 0)
 698                 size = size_machine;
 699
 700         return size;
 701 }
 702
 703 static inline bool
 704 bpf_ctx_narrow_access_ok(u32 off, u32 size, u32 size_default)
 705 {
 706         return size <= size_default && (size & (size - 1)) == 0;
 707 }
 708
 709 #define bpf_classic_proglen(fprog) (fprog->len * sizeof(fprog->filter[0]))
 710
 711 static inline void bpf_prog_lock_ro(struct bpf_prog *fp)
 712 {
 713         fp->undo_set_mem = 1;
 714         set_memory_ro((unsigned long)fp, fp->pages);
 715 }
 716
 717 static inline void bpf_prog_unlock_ro(struct bpf_prog *fp)
 718 {
 719         if (fp->undo_set_mem)
 720                 set_memory_rw((unsigned long)fp, fp->pages);
 721 }
 722
 723 static inline void bpf_jit_binary_lock_ro(struct bpf_binary_header *hdr)
 724 {
 725         set_memory_ro((unsigned long)hdr, hdr->pages);
 726         set_memory_x((unsigned long)hdr, hdr->pages);
 727 }
 728
 729 static inline void bpf_jit_binary_unlock_ro(struct bpf_binary_header *hdr)
 730 {
 731         set_memory_rw((unsigned long)hdr, hdr->pages);
 732 }
 733
 734 static inline struct bpf_binary_header *
 735 bpf_jit_binary_hdr(const struct bpf_prog *fp)
 736 {
 737         unsigned long real_start = (unsigned long)fp->bpf_func;
 738         unsigned long addr = real_start & PAGE_MASK;
 739
 740         return (void *)addr;
 741 }
 742
 743 int sk_filter_trim_cap(struct sock *sk, struct sk_buff *skb, unsigned int cap);
 744 static inline int sk_filter(struct sock *sk, struct sk_buff *skb)
 745 {
 746         return sk_filter_trim_cap(sk, skb, 1);
 747 }
 748
 749 struct bpf_prog *bpf_prog_select_runtime(struct bpf_prog *fp, int *err);
 750 void bpf_prog_free(struct bpf_prog *fp);
 751
 752 bool bpf_opcode_in_insntable(u8 code);
 753
 754 struct bpf_prog *bpf_prog_alloc(unsigned int size, gfp_t gfp_extra_flags);
 755 struct bpf_prog *bpf_prog_realloc(struct bpf_prog *fp_old, unsigned int size,
 756                                   gfp_t gfp_extra_flags);
 757 void __bpf_prog_free(struct bpf_prog *fp);
 758
 759 static inline void bpf_prog_unlock_free(struct bpf_prog *fp)
 760 {
 761         bpf_prog_unlock_ro(fp);
 762         __bpf_prog_free(fp);
 763 }
 764
 765 typedef int (*bpf_aux_classic_check_t)(struct sock_filter *filter,
 766                                        unsigned int flen);
 767
 768 int bpf_prog_create(struct bpf_prog **pfp, struct sock_fprog_kern *fprog);
 769 int bpf_prog_create_from_user(struct bpf_prog **pfp, struct sock_fprog *fprog,
 770                               bpf_aux_classic_check_t trans, bool save_orig);
 771 void bpf_prog_destroy(struct bpf_prog *fp);
 772
 773 int sk_attach_filter(struct sock_fprog *fprog, struct sock *sk);
 774 int sk_attach_bpf(u32 ufd, struct sock *sk);
 775 int sk_reuseport_attach_filter(struct sock_fprog *fprog, struct sock *sk);
 776 int sk_reuseport_attach_bpf(u32 ufd, struct sock *sk);
 777 void sk_reuseport_prog_free(struct bpf_prog *prog);
 778 int sk_detach_filter(struct sock *sk);
 779 int sk_get_filter(struct sock *sk, struct sock_filter __user *filter,
 780                   unsigned int len);
 781
 782 bool sk_filter_charge(struct sock *sk, struct sk_filter *fp);
 783 void sk_filter_uncharge(struct sock *sk, struct sk_filter *fp);
 784
 785 u64 __bpf_call_base(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5);
 786 #define __bpf_call_base_args \
 787         ((u64 (*)(u64, u64, u64, u64, u64, const struct bpf_insn *)) \
 788          (void *)__bpf_call_base)
 789
 790 struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog);
 791 void bpf_jit_compile(struct bpf_prog *prog);
 792 bool bpf_helper_changes_pkt_data(void *func);
 793
 794 static inline bool bpf_dump_raw_ok(const struct cred *cred)
 795 {
 796         /* Reconstruction of call-sites is dependent on kallsyms,
 797          * thus make dump the same restriction.
 798          */
 799         return kallsyms_show_value(cred);
 800 }
 801
 802 struct bpf_prog *bpf_patch_insn_single(struct bpf_prog *prog, u32 off,
 803                                        const struct bpf_insn *patch, u32 len);
 804
 805 void bpf_clear_redirect_map(struct bpf_map *map);
 806
 807 static inline bool xdp_return_frame_no_direct(void)
 808 {
 809         struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
 810
 811         return ri->kern_flags & BPF_RI_F_RF_NO_DIRECT;
 812 }
 813
 814 static inline void xdp_set_return_frame_no_direct(void)
 815 {
 816         struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
 817
 818         ri->kern_flags |= BPF_RI_F_RF_NO_DIRECT;
 819 }
 820
 821 static inline void xdp_clear_return_frame_no_direct(void)
 822 {
 823         struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
 824
 825         ri->kern_flags &= ~BPF_RI_F_RF_NO_DIRECT;
 826 }
 827
 828 static inline int xdp_ok_fwd_dev(const struct net_device *fwd,
 829                                  unsigned int pktlen)
 830 {
 831         unsigned int len;
 832
 833         if (unlikely(!(fwd->flags & IFF_UP)))
 834                 return -ENETDOWN;
 835
 836         len = fwd->mtu + fwd->hard_header_len + VLAN_HLEN;
 837         if (pktlen > len)
 838                 return -EMSGSIZE;
 839
 840         return 0;
 841 }
 842
 843 /* The pair of xdp_do_redirect and xdp_do_flush_map MUST be called in the
 844  * same cpu context. Further for best results no more than a single map
 845  * for the do_redirect/do_flush pair should be used. This limitation is
 846  * because we only track one map and force a flush when the map changes.
 847  * This does not appear to be a real limitation for existing software.
 848  */
 849 int xdp_do_generic_redirect(struct net_device *dev, struct sk_buff *skb,
 850                             struct xdp_buff *xdp, struct bpf_prog *prog);
 851 int xdp_do_redirect(struct net_device *dev,
 852                     struct xdp_buff *xdp,
 853                     struct bpf_prog *prog);
 854 void xdp_do_flush_map(void);
 855
 856 void bpf_warn_invalid_xdp_action(u32 act);
 857
 858 struct sock *do_sk_redirect_map(struct sk_buff *skb);
 859 struct sock *do_msg_redirect_map(struct sk_msg_buff *md);
 860
 861 #ifdef CONFIG_INET
 862 struct sock *bpf_run_sk_reuseport(struct sock_reuseport *reuse, struct sock *sk,
 863                                   struct bpf_prog *prog, struct sk_buff *skb,
 864                                   u32 hash);
 865 #else
 866 static inline struct sock *
 867 bpf_run_sk_reuseport(struct sock_reuseport *reuse, struct sock *sk,
 868                      struct bpf_prog *prog, struct sk_buff *skb,
 869                      u32 hash)
 870 {
 871         return NULL;
 872 }
 873 #endif
 874
 875 #ifdef CONFIG_BPF_JIT
 876 extern int bpf_jit_enable;
 877 extern int bpf_jit_harden;
 878 extern int bpf_jit_kallsyms;
 879 extern long bpf_jit_limit;
 880 extern long bpf_jit_limit_max;
 881
 882 typedef void (*bpf_jit_fill_hole_t)(void *area, unsigned int size);
 883
 884 struct bpf_binary_header *
 885 bpf_jit_binary_alloc(unsigned int proglen, u8 **image_ptr,
 886                      unsigned int alignment,
 887                      bpf_jit_fill_hole_t bpf_fill_ill_insns);
 888 void bpf_jit_binary_free(struct bpf_binary_header *hdr);
 889 u64 bpf_jit_alloc_exec_limit(void);
 890 void *bpf_jit_alloc_exec(unsigned long size);
 891 void bpf_jit_free_exec(void *addr);
 892 void bpf_jit_free(struct bpf_prog *fp);
 893
 894 struct bpf_prog *bpf_jit_blind_constants(struct bpf_prog *fp);
 895 void bpf_jit_prog_release_other(struct bpf_prog *fp, struct bpf_prog *fp_other);
 896
 897 static inline void bpf_jit_dump(unsigned int flen, unsigned int proglen,
 898                                 u32 pass, void *image)
 899 {
 900         pr_err("flen=%u proglen=%u pass=%u image=%pK from=%s pid=%d\n", flen,
 901                proglen, pass, image, current->comm, task_pid_nr(current));
 902
 903         if (image)
 904                 print_hex_dump(KERN_ERR, "JIT code: ", DUMP_PREFIX_OFFSET,
 905                                16, 1, image, proglen, false);
 906 }
 907
 908 static inline bool bpf_jit_is_ebpf(void)
 909 {
 910 # ifdef CONFIG_HAVE_EBPF_JIT
 911         return true;
 912 # else
 913         return false;
 914 # endif
 915 }
 916
 917 static inline bool ebpf_jit_enabled(void)
 918 {
 919         return bpf_jit_enable && bpf_jit_is_ebpf();
 920 }
 921
 922 static inline bool bpf_prog_ebpf_jited(const struct bpf_prog *fp)
 923 {
 924         return fp->jited && bpf_jit_is_ebpf();
 925 }
 926
 927 static inline bool bpf_jit_blinding_enabled(struct bpf_prog *prog)
 928 {
 929         /* These are the prerequisites, should someone ever have the
 930          * idea to call blinding outside of them, we make sure to
 931          * bail out.
 932          */
 933         if (!bpf_jit_is_ebpf())
 934                 return false;
 935         if (!prog->jit_requested)
 936                 return false;
 937         if (!bpf_jit_harden)
 938                 return false;
 939         if (bpf_jit_harden == 1 && capable(CAP_SYS_ADMIN))
 940                 return false;
 941
 942         return true;
 943 }
 944
 945 static inline bool bpf_jit_kallsyms_enabled(void)
 946 {
 947         /* There are a couple of corner cases where kallsyms should
 948          * not be enabled f.e. on hardening.
 949          */
 950         if (bpf_jit_harden)
 951                 return false;
 952         if (!bpf_jit_kallsyms)
 953                 return false;
 954         if (bpf_jit_kallsyms == 1)
 955                 return true;
 956
 957         return false;
 958 }
 959
 960 const char *__bpf_address_lookup(unsigned long addr, unsigned long *size,
 961                                  unsigned long *off, char *sym);
 962 bool is_bpf_text_address(unsigned long addr);
 963 int bpf_get_kallsym(unsigned int symnum, unsigned long *value, char *type,
 964                     char *sym);
 965
 966 static inline const char *
 967 bpf_address_lookup(unsigned long addr, unsigned long *size,
 968                    unsigned long *off, char **modname, char *sym)
 969 {
 970         const char *ret = __bpf_address_lookup(addr, size, off, sym);
 971
 972         if (ret && modname)
 973                 *modname = NULL;
 974         return ret;
 975 }
 976
 977 void bpf_prog_kallsyms_add(struct bpf_prog *fp);
 978 void bpf_prog_kallsyms_del(struct bpf_prog *fp);
 979
 980 #else /* CONFIG_BPF_JIT */
 981
 982 static inline bool ebpf_jit_enabled(void)
 983 {
 984         return false;
 985 }
 986
 987 static inline bool bpf_prog_ebpf_jited(const struct bpf_prog *fp)
 988 {
 989         return false;
 990 }
 991
 992 static inline void bpf_jit_free(struct bpf_prog *fp)
 993 {
 994         bpf_prog_unlock_free(fp);
 995 }
 996
 997 static inline bool bpf_jit_kallsyms_enabled(void)
 998 {
 999         return false;
1000 }
1001
1002 static inline const char *
1003 __bpf_address_lookup(unsigned long addr, unsigned long *size,
1004                      unsigned long *off, char *sym)
1005 {
1006         return NULL;
1007 }
1008
1009 static inline bool is_bpf_text_address(unsigned long addr)
1010 {
1011         return false;
1012 }
1013
1014 static inline int bpf_get_kallsym(unsigned int symnum, unsigned long *value,
1015                                   char *type, char *sym)
1016 {
1017         return -ERANGE;
1018 }
1019
1020 static inline const char *
1021 bpf_address_lookup(unsigned long addr, unsigned long *size,
1022                    unsigned long *off, char **modname, char *sym)
1023 {
1024         return NULL;
1025 }
1026
1027 static inline void bpf_prog_kallsyms_add(struct bpf_prog *fp)
1028 {
1029 }
1030
1031 static inline void bpf_prog_kallsyms_del(struct bpf_prog *fp)
1032 {
1033 }
1034 #endif /* CONFIG_BPF_JIT */
1035
1036 void bpf_prog_kallsyms_del_subprogs(struct bpf_prog *fp);
1037 void bpf_prog_kallsyms_del_all(struct bpf_prog *fp);
1038
1039 #define BPF_ANC         BIT(15)
1040
1041 static inline bool bpf_needs_clear_a(const struct sock_filter *first)
1042 {
1043         switch (first->code) {
1044         case BPF_RET | BPF_K:
1045         case BPF_LD | BPF_W | BPF_LEN:
1046                 return false;
1047
1048         case BPF_LD | BPF_W | BPF_ABS:
1049         case BPF_LD | BPF_H | BPF_ABS:
1050         case BPF_LD | BPF_B | BPF_ABS:
1051                 if (first->k == SKF_AD_OFF + SKF_AD_ALU_XOR_X)
1052                         return true;
1053                 return false;
1054
1055         default:
1056                 return true;
1057         }
1058 }
1059
1060 static inline u16 bpf_anc_helper(const struct sock_filter *ftest)
1061 {
1062         BUG_ON(ftest->code & BPF_ANC);
1063
1064         switch (ftest->code) {
1065         case BPF_LD | BPF_W | BPF_ABS:
1066         case BPF_LD | BPF_H | BPF_ABS:
1067         case BPF_LD | BPF_B | BPF_ABS:
1068 #define BPF_ANCILLARY(CODE)     case SKF_AD_OFF + SKF_AD_##CODE:        \
1069                                 return BPF_ANC | SKF_AD_##CODE
1070                 switch (ftest->k) {
1071                 BPF_ANCILLARY(PROTOCOL);
1072                 BPF_ANCILLARY(PKTTYPE);
1073                 BPF_ANCILLARY(IFINDEX);
1074                 BPF_ANCILLARY(NLATTR);
1075                 BPF_ANCILLARY(NLATTR_NEST);
1076                 BPF_ANCILLARY(MARK);
1077                 BPF_ANCILLARY(QUEUE);
1078                 BPF_ANCILLARY(HATYPE);
1079                 BPF_ANCILLARY(RXHASH);
1080                 BPF_ANCILLARY(CPU);
1081                 BPF_ANCILLARY(ALU_XOR_X);
1082                 BPF_ANCILLARY(VLAN_TAG);
1083                 BPF_ANCILLARY(VLAN_TAG_PRESENT);
1084                 BPF_ANCILLARY(PAY_OFFSET);
1085                 BPF_ANCILLARY(RANDOM);
1086                 BPF_ANCILLARY(VLAN_TPID);
1087                 }
1088                 /* Fallthrough. */
1089         default:
1090                 return ftest->code;
1091         }
1092 }
1093
1094 void *bpf_internal_load_pointer_neg_helper(const struct sk_buff *skb,
1095                                            int k, unsigned int size);
1096
1097 static inline void *bpf_load_pointer(const struct sk_buff *skb, int k,
1098                                      unsigned int size, void *buffer)
1099 {
1100         if (k >= 0)
1101                 return skb_header_pointer(skb, k, size, buffer);
1102
1103         return bpf_internal_load_pointer_neg_helper(skb, k, size);
1104 }
1105
1106 static inline int bpf_tell_extensions(void)
1107 {
1108         return SKF_AD_MAX;
1109 }
1110
1111 struct bpf_sock_addr_kern {
1112         struct sock *sk;
1113         struct sockaddr *uaddr;
1114         /* Temporary "register" to make indirect stores to nested structures
1115          * defined above. We need three registers to make such a store, but
1116          * only two (src and dst) are available at convert_ctx_access time
1117          */
1118         u64 tmp_reg;
1119         void *t_ctx;    /* Attach type specific context. */
1120 };
1121
1122 struct bpf_sock_ops_kern {
1123         struct  sock *sk;
1124         u32     op;
1125         union {
1126                 u32 args[4];
1127                 u32 reply;
1128                 u32 replylong[4];
1129         };
1130         u32     is_fullsock;
1131         u64     temp;                   /* temp and everything after is not
1132                                          * initialized to 0 before calling
1133                                          * the BPF program. New fields that
1134                                          * should be initialized to 0 should
1135                                          * be inserted before temp.
1136                                          * temp is scratch storage used by
1137                                          * sock_ops_convert_ctx_access
1138                                          * as temporary storage of a register.
1139                                          */
1140 };
1141
1142 #endif /* __LINUX_FILTER_H__ */