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