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/sha.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 /* unused opcode to mark speculation barrier for mitigating
  76  * Speculative Store Bypass
  77  */
  78 #define BPF_NOSPEC      0xc0
  79
  80 /* As per nm, we expose JITed images as text (code) section for
  81  * kallsyms. That way, tools like perf can find it to match
  82  * addresses.
  83  */
  84 #define BPF_SYM_ELF_TYPE        't'
  85
  86 /* BPF program can access up to 512 bytes of stack space. */
  87 #define MAX_BPF_STACK   512
  88
  89 /* Helper macros for filter block array initializers. */
  90
  91 /* ALU ops on registers, bpf_add|sub|...: dst_reg += src_reg */
  92
  93 #define BPF_ALU64_REG(OP, DST, SRC)                             \
  94         ((struct bpf_insn) {                                    \
  95                 .code  = BPF_ALU64 | BPF_OP(OP) | BPF_X,        \
  96                 .dst_reg = DST,                                 \
  97                 .src_reg = SRC,                                 \
  98                 .off   = 0,                                     \
  99                 .imm   = 0 })
 100
 101 #define BPF_ALU32_REG(OP, DST, SRC)                             \
 102         ((struct bpf_insn) {                                    \
 103                 .code  = BPF_ALU | BPF_OP(OP) | BPF_X,          \
 104                 .dst_reg = DST,                                 \
 105                 .src_reg = SRC,                                 \
 106                 .off   = 0,                                     \
 107                 .imm   = 0 })
 108
 109 /* ALU ops on immediates, bpf_add|sub|...: dst_reg += imm32 */
 110
 111 #define BPF_ALU64_IMM(OP, DST, IMM)                             \
 112         ((struct bpf_insn) {                                    \
 113                 .code  = BPF_ALU64 | BPF_OP(OP) | BPF_K,        \
 114                 .dst_reg = DST,                                 \
 115                 .src_reg = 0,                                   \
 116                 .off   = 0,                                     \
 117                 .imm   = IMM })
 118
 119 #define BPF_ALU32_IMM(OP, DST, IMM)                             \
 120         ((struct bpf_insn) {                                    \
 121                 .code  = BPF_ALU | BPF_OP(OP) | BPF_K,          \
 122                 .dst_reg = DST,                                 \
 123                 .src_reg = 0,                                   \
 124                 .off   = 0,                                     \
 125                 .imm   = IMM })
 126
 127 /* Endianess conversion, cpu_to_{l,b}e(), {l,b}e_to_cpu() */
 128
 129 #define BPF_ENDIAN(TYPE, DST, LEN)                              \
 130         ((struct bpf_insn) {                                    \
 131                 .code  = BPF_ALU | BPF_END | BPF_SRC(TYPE),     \
 132                 .dst_reg = DST,                                 \
 133                 .src_reg = 0,                                   \
 134                 .off   = 0,                                     \
 135                 .imm   = LEN })
 136
 137 /* Short form of mov, dst_reg = src_reg */
 138
 139 #define BPF_MOV64_REG(DST, SRC)                                 \
 140         ((struct bpf_insn) {                                    \
 141                 .code  = BPF_ALU64 | BPF_MOV | BPF_X,           \
 142                 .dst_reg = DST,                                 \
 143                 .src_reg = SRC,                                 \
 144                 .off   = 0,                                     \
 145                 .imm   = 0 })
 146
 147 #define BPF_MOV32_REG(DST, SRC)                                 \
 148         ((struct bpf_insn) {                                    \
 149                 .code  = BPF_ALU | BPF_MOV | BPF_X,             \
 150                 .dst_reg = DST,                                 \
 151                 .src_reg = SRC,                                 \
 152                 .off   = 0,                                     \
 153                 .imm   = 0 })
 154
 155 /* Short form of mov, dst_reg = imm32 */
 156
 157 #define BPF_MOV64_IMM(DST, IMM)                                 \
 158         ((struct bpf_insn) {                                    \
 159                 .code  = BPF_ALU64 | BPF_MOV | BPF_K,           \
 160                 .dst_reg = DST,                                 \
 161                 .src_reg = 0,                                   \
 162                 .off   = 0,                                     \
 163                 .imm   = IMM })
 164
 165 #define BPF_MOV32_IMM(DST, IMM)                                 \
 166         ((struct bpf_insn) {                                    \
 167                 .code  = BPF_ALU | BPF_MOV | BPF_K,             \
 168                 .dst_reg = DST,                                 \
 169                 .src_reg = 0,                                   \
 170                 .off   = 0,                                     \
 171                 .imm   = IMM })
 172
 173 /* Special form of mov32, used for doing explicit zero extension on dst. */
 174 #define BPF_ZEXT_REG(DST)                                       \
 175         ((struct bpf_insn) {                                    \
 176                 .code  = BPF_ALU | BPF_MOV | BPF_X,             \
 177                 .dst_reg = DST,                                 \
 178                 .src_reg = DST,                                 \
 179                 .off   = 0,                                     \
 180                 .imm   = 1 })
 181
 182 static inline bool insn_is_zext(const struct bpf_insn *insn)
 183 {
 184         return insn->code == (BPF_ALU | BPF_MOV | BPF_X) && insn->imm == 1;
 185 }
 186
 187 /* BPF_LD_IMM64 macro encodes single 'load 64-bit immediate' insn */
 188 #define BPF_LD_IMM64(DST, IMM)                                  \
 189         BPF_LD_IMM64_RAW(DST, 0, IMM)
 190
 191 #define BPF_LD_IMM64_RAW(DST, SRC, IMM)                         \
 192         ((struct bpf_insn) {                                    \
 193                 .code  = BPF_LD | BPF_DW | BPF_IMM,             \
 194                 .dst_reg = DST,                                 \
 195                 .src_reg = SRC,                                 \
 196                 .off   = 0,                                     \
 197                 .imm   = (__u32) (IMM) }),                      \
 198         ((struct bpf_insn) {                                    \
 199                 .code  = 0, /* zero is reserved opcode */       \
 200                 .dst_reg = 0,                                   \
 201                 .src_reg = 0,                                   \
 202                 .off   = 0,                                     \
 203                 .imm   = ((__u64) (IMM)) >> 32 })
 204
 205 /* pseudo BPF_LD_IMM64 insn used to refer to process-local map_fd */
 206 #define BPF_LD_MAP_FD(DST, MAP_FD)                              \
 207         BPF_LD_IMM64_RAW(DST, BPF_PSEUDO_MAP_FD, MAP_FD)
 208
 209 /* Short form of mov based on type, BPF_X: dst_reg = src_reg, BPF_K: dst_reg = imm32 */
 210
 211 #define BPF_MOV64_RAW(TYPE, DST, SRC, IMM)                      \
 212         ((struct bpf_insn) {                                    \
 213                 .code  = BPF_ALU64 | BPF_MOV | BPF_SRC(TYPE),   \
 214                 .dst_reg = DST,                                 \
 215                 .src_reg = SRC,                                 \
 216                 .off   = 0,                                     \
 217                 .imm   = IMM })
 218
 219 #define BPF_MOV32_RAW(TYPE, DST, SRC, IMM)                      \
 220         ((struct bpf_insn) {                                    \
 221                 .code  = BPF_ALU | BPF_MOV | BPF_SRC(TYPE),     \
 222                 .dst_reg = DST,                                 \
 223                 .src_reg = SRC,                                 \
 224                 .off   = 0,                                     \
 225                 .imm   = IMM })
 226
 227 /* Direct packet access, R0 = *(uint *) (skb->data + imm32) */
 228
 229 #define BPF_LD_ABS(SIZE, IMM)                                   \
 230         ((struct bpf_insn) {                                    \
 231                 .code  = BPF_LD | BPF_SIZE(SIZE) | BPF_ABS,     \
 232                 .dst_reg = 0,                                   \
 233                 .src_reg = 0,                                   \
 234                 .off   = 0,                                     \
 235                 .imm   = IMM })
 236
 237 /* Indirect packet access, R0 = *(uint *) (skb->data + src_reg + imm32) */
 238
 239 #define BPF_LD_IND(SIZE, SRC, IMM)                              \
 240         ((struct bpf_insn) {                                    \
 241                 .code  = BPF_LD | BPF_SIZE(SIZE) | BPF_IND,     \
 242                 .dst_reg = 0,                                   \
 243                 .src_reg = SRC,                                 \
 244                 .off   = 0,                                     \
 245                 .imm   = IMM })
 246
 247 /* Memory load, dst_reg = *(uint *) (src_reg + off16) */
 248
 249 #define BPF_LDX_MEM(SIZE, DST, SRC, OFF)                        \
 250         ((struct bpf_insn) {                                    \
 251                 .code  = BPF_LDX | BPF_SIZE(SIZE) | BPF_MEM,    \
 252                 .dst_reg = DST,                                 \
 253                 .src_reg = SRC,                                 \
 254                 .off   = OFF,                                   \
 255                 .imm   = 0 })
 256
 257 /* Memory store, *(uint *) (dst_reg + off16) = src_reg */
 258
 259 #define BPF_STX_MEM(SIZE, DST, SRC, OFF)                        \
 260         ((struct bpf_insn) {                                    \
 261                 .code  = BPF_STX | BPF_SIZE(SIZE) | BPF_MEM,    \
 262                 .dst_reg = DST,                                 \
 263                 .src_reg = SRC,                                 \
 264                 .off   = OFF,                                   \
 265                 .imm   = 0 })
 266
 267 /* Atomic memory add, *(uint *)(dst_reg + off16) += src_reg */
 268
 269 #define BPF_STX_XADD(SIZE, DST, SRC, OFF)                       \
 270         ((struct bpf_insn) {                                    \
 271                 .code  = BPF_STX | BPF_SIZE(SIZE) | BPF_XADD,   \
 272                 .dst_reg = DST,                                 \
 273                 .src_reg = SRC,                                 \
 274                 .off   = OFF,                                   \
 275                 .imm   = 0 })
 276
 277 /* Memory store, *(uint *) (dst_reg + off16) = imm32 */
 278
 279 #define BPF_ST_MEM(SIZE, DST, OFF, IMM)                         \
 280         ((struct bpf_insn) {                                    \
 281                 .code  = BPF_ST | BPF_SIZE(SIZE) | BPF_MEM,     \
 282                 .dst_reg = DST,                                 \
 283                 .src_reg = 0,                                   \
 284                 .off   = OFF,                                   \
 285                 .imm   = IMM })
 286
 287 /* Conditional jumps against registers, if (dst_reg 'op' src_reg) goto pc + off16 */
 288
 289 #define BPF_JMP_REG(OP, DST, SRC, OFF)                          \
 290         ((struct bpf_insn) {                                    \
 291                 .code  = BPF_JMP | BPF_OP(OP) | BPF_X,          \
 292                 .dst_reg = DST,                                 \
 293                 .src_reg = SRC,                                 \
 294                 .off   = OFF,                                   \
 295                 .imm   = 0 })
 296
 297 /* Conditional jumps against immediates, if (dst_reg 'op' imm32) goto pc + off16 */
 298
 299 #define BPF_JMP_IMM(OP, DST, IMM, OFF)                          \
 300         ((struct bpf_insn) {                                    \
 301                 .code  = BPF_JMP | BPF_OP(OP) | BPF_K,          \
 302                 .dst_reg = DST,                                 \
 303                 .src_reg = 0,                                   \
 304                 .off   = OFF,                                   \
 305                 .imm   = IMM })
 306
 307 /* Like BPF_JMP_REG, but with 32-bit wide operands for comparison. */
 308
 309 #define BPF_JMP32_REG(OP, DST, SRC, OFF)                        \
 310         ((struct bpf_insn) {                                    \
 311                 .code  = BPF_JMP32 | BPF_OP(OP) | BPF_X,        \
 312                 .dst_reg = DST,                                 \
 313                 .src_reg = SRC,                                 \
 314                 .off   = OFF,                                   \
 315                 .imm   = 0 })
 316
 317 /* Like BPF_JMP_IMM, but with 32-bit wide operands for comparison. */
 318
 319 #define BPF_JMP32_IMM(OP, DST, IMM, OFF)                        \
 320         ((struct bpf_insn) {                                    \
 321                 .code  = BPF_JMP32 | BPF_OP(OP) | BPF_K,        \
 322                 .dst_reg = DST,                                 \
 323                 .src_reg = 0,                                   \
 324                 .off   = OFF,                                   \
 325                 .imm   = IMM })
 326
 327 /* Unconditional jumps, goto pc + off16 */
 328
 329 #define BPF_JMP_A(OFF)                                          \
 330         ((struct bpf_insn) {                                    \
 331                 .code  = BPF_JMP | BPF_JA,                      \
 332                 .dst_reg = 0,                                   \
 333                 .src_reg = 0,                                   \
 334                 .off   = OFF,                                   \
 335                 .imm   = 0 })
 336
 337 /* Relative call */
 338
 339 #define BPF_CALL_REL(TGT)                                       \
 340         ((struct bpf_insn) {                                    \
 341                 .code  = BPF_JMP | BPF_CALL,                    \
 342                 .dst_reg = 0,                                   \
 343                 .src_reg = BPF_PSEUDO_CALL,                     \
 344                 .off   = 0,                                     \
 345                 .imm   = TGT })
 346
 347 /* Function call */
 348
 349 #define BPF_CAST_CALL(x)                                        \
 350                 ((u64 (*)(u64, u64, u64, u64, u64))(x))
 351
 352 #define BPF_EMIT_CALL(FUNC)                                     \
 353         ((struct bpf_insn) {                                    \
 354                 .code  = BPF_JMP | BPF_CALL,                    \
 355                 .dst_reg = 0,                                   \
 356                 .src_reg = 0,                                   \
 357                 .off   = 0,                                     \
 358                 .imm   = ((FUNC) - __bpf_call_base) })
 359
 360 /* Raw code statement block */
 361
 362 #define BPF_RAW_INSN(CODE, DST, SRC, OFF, IMM)                  \
 363         ((struct bpf_insn) {                                    \
 364                 .code  = CODE,                                  \
 365                 .dst_reg = DST,                                 \
 366                 .src_reg = SRC,                                 \
 367                 .off   = OFF,                                   \
 368                 .imm   = IMM })
 369
 370 /* Program exit */
 371
 372 #define BPF_EXIT_INSN()                                         \
 373         ((struct bpf_insn) {                                    \
 374                 .code  = BPF_JMP | BPF_EXIT,                    \
 375                 .dst_reg = 0,                                   \
 376                 .src_reg = 0,                                   \
 377                 .off   = 0,                                     \
 378                 .imm   = 0 })
 379
 380 /* Speculation barrier */
 381
 382 #define BPF_ST_NOSPEC()                                         \
 383         ((struct bpf_insn) {                                    \
 384                 .code  = BPF_ST | BPF_NOSPEC,                   \
 385                 .dst_reg = 0,                                   \
 386                 .src_reg = 0,                                   \
 387                 .off   = 0,                                     \
 388                 .imm   = 0 })
 389
 390 /* Internal classic blocks for direct assignment */
 391
 392 #define __BPF_STMT(CODE, K)                                     \
 393         ((struct sock_filter) BPF_STMT(CODE, K))
 394
 395 #define __BPF_JUMP(CODE, K, JT, JF)                             \
 396         ((struct sock_filter) BPF_JUMP(CODE, K, JT, JF))
 397
 398 #define bytes_to_bpf_size(bytes)                                \
 399 ({                                                              \
 400         int bpf_size = -EINVAL;                                 \
 401                                                                 \
 402         if (bytes == sizeof(u8))                                \
 403                 bpf_size = BPF_B;                               \
 404         else if (bytes == sizeof(u16))                          \
 405                 bpf_size = BPF_H;                               \
 406         else if (bytes == sizeof(u32))                          \
 407                 bpf_size = BPF_W;                               \
 408         else if (bytes == sizeof(u64))                          \
 409                 bpf_size = BPF_DW;                              \
 410                                                                 \
 411         bpf_size;                                               \
 412 })
 413
 414 #define bpf_size_to_bytes(bpf_size)                             \
 415 ({                                                              \
 416         int bytes = -EINVAL;                                    \
 417                                                                 \
 418         if (bpf_size == BPF_B)                                  \
 419                 bytes = sizeof(u8);                             \
 420         else if (bpf_size == BPF_H)                             \
 421                 bytes = sizeof(u16);                            \
 422         else if (bpf_size == BPF_W)                             \
 423                 bytes = sizeof(u32);                            \
 424         else if (bpf_size == BPF_DW)                            \
 425                 bytes = sizeof(u64);                            \
 426                                                                 \
 427         bytes;                                                  \
 428 })
 429
 430 #define BPF_SIZEOF(type)                                        \
 431         ({                                                      \
 432                 const int __size = bytes_to_bpf_size(sizeof(type)); \
 433                 BUILD_BUG_ON(__size < 0);                       \
 434                 __size;                                         \
 435         })
 436
 437 #define BPF_FIELD_SIZEOF(type, field)                           \
 438         ({                                                      \
 439                 const int __size = bytes_to_bpf_size(sizeof_field(type, field)); \
 440                 BUILD_BUG_ON(__size < 0);                       \
 441                 __size;                                         \
 442         })
 443
 444 #define BPF_LDST_BYTES(insn)                                    \
 445         ({                                                      \
 446                 const int __size = bpf_size_to_bytes(BPF_SIZE((insn)->code)); \
 447                 WARN_ON(__size < 0);                            \
 448                 __size;                                         \
 449         })
 450
 451 #define __BPF_MAP_0(m, v, ...) v
 452 #define __BPF_MAP_1(m, v, t, a, ...) m(t, a)
 453 #define __BPF_MAP_2(m, v, t, a, ...) m(t, a), __BPF_MAP_1(m, v, __VA_ARGS__)
 454 #define __BPF_MAP_3(m, v, t, a, ...) m(t, a), __BPF_MAP_2(m, v, __VA_ARGS__)
 455 #define __BPF_MAP_4(m, v, t, a, ...) m(t, a), __BPF_MAP_3(m, v, __VA_ARGS__)
 456 #define __BPF_MAP_5(m, v, t, a, ...) m(t, a), __BPF_MAP_4(m, v, __VA_ARGS__)
 457
 458 #define __BPF_REG_0(...) __BPF_PAD(5)
 459 #define __BPF_REG_1(...) __BPF_MAP(1, __VA_ARGS__), __BPF_PAD(4)
 460 #define __BPF_REG_2(...) __BPF_MAP(2, __VA_ARGS__), __BPF_PAD(3)
 461 #define __BPF_REG_3(...) __BPF_MAP(3, __VA_ARGS__), __BPF_PAD(2)
 462 #define __BPF_REG_4(...) __BPF_MAP(4, __VA_ARGS__), __BPF_PAD(1)
 463 #define __BPF_REG_5(...) __BPF_MAP(5, __VA_ARGS__)
 464
 465 #define __BPF_MAP(n, ...) __BPF_MAP_##n(__VA_ARGS__)
 466 #define __BPF_REG(n, ...) __BPF_REG_##n(__VA_ARGS__)
 467
 468 #define __BPF_CAST(t, a)                                                       \
 469         (__force t)                                                            \
 470         (__force                                                               \
 471          typeof(__builtin_choose_expr(sizeof(t) == sizeof(unsigned long),      \
 472                                       (unsigned long)0, (t)0))) a
 473 #define __BPF_V void
 474 #define __BPF_N
 475
 476 #define __BPF_DECL_ARGS(t, a) t   a
 477 #define __BPF_DECL_REGS(t, a) u64 a
 478
 479 #define __BPF_PAD(n)                                                           \
 480         __BPF_MAP(n, __BPF_DECL_ARGS, __BPF_N, u64, __ur_1, u64, __ur_2,       \
 481                   u64, __ur_3, u64, __ur_4, u64, __ur_5)
 482
 483 #define BPF_CALL_x(x, name, ...)                                               \
 484         static __always_inline                                                 \
 485         u64 ____##name(__BPF_MAP(x, __BPF_DECL_ARGS, __BPF_V, __VA_ARGS__));   \
 486         typedef u64 (*btf_##name)(__BPF_MAP(x, __BPF_DECL_ARGS, __BPF_V, __VA_ARGS__)); \
 487         u64 name(__BPF_REG(x, __BPF_DECL_REGS, __BPF_N, __VA_ARGS__));         \
 488         u64 name(__BPF_REG(x, __BPF_DECL_REGS, __BPF_N, __VA_ARGS__))          \
 489         {                                                                      \
 490                 return ((btf_##name)____##name)(__BPF_MAP(x,__BPF_CAST,__BPF_N,__VA_ARGS__));\
 491         }                                                                      \
 492         static __always_inline                                                 \
 493         u64 ____##name(__BPF_MAP(x, __BPF_DECL_ARGS, __BPF_V, __VA_ARGS__))
 494
 495 #define BPF_CALL_0(name, ...)   BPF_CALL_x(0, name, __VA_ARGS__)
 496 #define BPF_CALL_1(name, ...)   BPF_CALL_x(1, name, __VA_ARGS__)
 497 #define BPF_CALL_2(name, ...)   BPF_CALL_x(2, name, __VA_ARGS__)
 498 #define BPF_CALL_3(name, ...)   BPF_CALL_x(3, name, __VA_ARGS__)
 499 #define BPF_CALL_4(name, ...)   BPF_CALL_x(4, name, __VA_ARGS__)
 500 #define BPF_CALL_5(name, ...)   BPF_CALL_x(5, name, __VA_ARGS__)
 501
 502 #define bpf_ctx_range(TYPE, MEMBER)                                             \
 503         offsetof(TYPE, MEMBER) ... offsetofend(TYPE, MEMBER) - 1
 504 #define bpf_ctx_range_till(TYPE, MEMBER1, MEMBER2)                              \
 505         offsetof(TYPE, MEMBER1) ... offsetofend(TYPE, MEMBER2) - 1
 506 #if BITS_PER_LONG == 64
 507 # define bpf_ctx_range_ptr(TYPE, MEMBER)                                        \
 508         offsetof(TYPE, MEMBER) ... offsetofend(TYPE, MEMBER) - 1
 509 #else
 510 # define bpf_ctx_range_ptr(TYPE, MEMBER)                                        \
 511         offsetof(TYPE, MEMBER) ... offsetof(TYPE, MEMBER) + 8 - 1
 512 #endif /* BITS_PER_LONG == 64 */
 513
 514 #define bpf_target_off(TYPE, MEMBER, SIZE, PTR_SIZE)                            \
 515         ({                                                                      \
 516                 BUILD_BUG_ON(sizeof_field(TYPE, MEMBER) != (SIZE));             \
 517                 *(PTR_SIZE) = (SIZE);                                           \
 518                 offsetof(TYPE, MEMBER);                                         \
 519         })
 520
 521 /* A struct sock_filter is architecture independent. */
 522 struct compat_sock_fprog {
 523         u16             len;
 524         compat_uptr_t   filter; /* struct sock_filter * */
 525 };
 526
 527 struct sock_fprog_kern {
 528         u16                     len;
 529         struct sock_filter      *filter;
 530 };
 531
 532 /* Some arches need doubleword alignment for their instructions and/or data */
 533 #define BPF_IMAGE_ALIGNMENT 8
 534
 535 struct bpf_binary_header {
 536         u32 pages;
 537         u8 image[] __aligned(BPF_IMAGE_ALIGNMENT);
 538 };
 539
 540 struct bpf_prog {
 541         u16                     pages;          /* Number of allocated pages */
 542         u16                     jited:1,        /* Is our filter JIT'ed? */
 543                                 jit_requested:1,/* archs need to JIT the prog */
 544                                 gpl_compatible:1, /* Is filter GPL compatible? */
 545                                 cb_access:1,    /* Is control block accessed? */
 546                                 dst_needed:1,   /* Do we need dst entry? */
 547                                 blinded:1,      /* Was blinded */
 548                                 is_func:1,      /* program is a bpf function */
 549                                 kprobe_override:1, /* Do we override a kprobe? */
 550                                 has_callchain_buf:1, /* callchain buffer allocated? */
 551                                 enforce_expected_attach_type:1, /* Enforce expected_attach_type checking at attach time */
 552                                 call_get_stack:1; /* Do we call bpf_get_stack() or bpf_get_stackid() */
 553         enum bpf_prog_type      type;           /* Type of BPF program */
 554         enum bpf_attach_type    expected_attach_type; /* For some prog types */
 555         u32                     len;            /* Number of filter blocks */
 556         u32                     jited_len;      /* Size of jited insns in bytes */
 557         u8                      tag[BPF_TAG_SIZE];
 558         struct bpf_prog_aux     *aux;           /* Auxiliary fields */
 559         struct sock_fprog_kern  *orig_prog;     /* Original BPF program */
 560         unsigned int            (*bpf_func)(const void *ctx,
 561                                             const struct bpf_insn *insn);
 562         /* Instructions for interpreter */
 563         struct sock_filter      insns[0];
 564         struct bpf_insn         insnsi[];
 565 };
 566
 567 struct sk_filter {
 568         refcount_t      refcnt;
 569         struct rcu_head rcu;
 570         struct bpf_prog *prog;
 571 };
 572
 573 DECLARE_STATIC_KEY_FALSE(bpf_stats_enabled_key);
 574
 575 #define __BPF_PROG_RUN(prog, ctx, dfunc)        ({                      \
 576         u32 __ret;                                                      \
 577         cant_migrate();                                                 \
 578         if (static_branch_unlikely(&bpf_stats_enabled_key)) {           \
 579                 struct bpf_prog_stats *__stats;                         \
 580                 u64 __start = sched_clock();                            \
 581                 __ret = dfunc(ctx, (prog)->insnsi, (prog)->bpf_func);   \
 582                 __stats = this_cpu_ptr(prog->aux->stats);               \
 583                 u64_stats_update_begin(&__stats->syncp);                \
 584                 __stats->cnt++;                                         \
 585                 __stats->nsecs += sched_clock() - __start;              \
 586                 u64_stats_update_end(&__stats->syncp);                  \
 587         } else {                                                        \
 588                 __ret = dfunc(ctx, (prog)->insnsi, (prog)->bpf_func);   \
 589         }                                                               \
 590         __ret; })
 591
 592 #define BPF_PROG_RUN(prog, ctx)                                         \
 593         __BPF_PROG_RUN(prog, ctx, bpf_dispatcher_nop_func)
 594
 595 /*
 596  * Use in preemptible and therefore migratable context to make sure that
 597  * the execution of the BPF program runs on one CPU.
 598  *
 599  * This uses migrate_disable/enable() explicitly to document that the
 600  * invocation of a BPF program does not require reentrancy protection
 601  * against a BPF program which is invoked from a preempting task.
 602  *
 603  * For non RT enabled kernels migrate_disable/enable() maps to
 604  * preempt_disable/enable(), i.e. it disables also preemption.
 605  */
 606 static inline u32 bpf_prog_run_pin_on_cpu(const struct bpf_prog *prog,
 607                                           const void *ctx)
 608 {
 609         u32 ret;
 610
 611         migrate_disable();
 612         ret = __BPF_PROG_RUN(prog, ctx, bpf_dispatcher_nop_func);
 613         migrate_enable();
 614         return ret;
 615 }
 616
 617 #define BPF_SKB_CB_LEN QDISC_CB_PRIV_LEN
 618
 619 struct bpf_skb_data_end {
 620         struct qdisc_skb_cb qdisc_cb;
 621         void *data_meta;
 622         void *data_end;
 623 };
 624
 625 struct bpf_nh_params {
 626         u32 nh_family;
 627         union {
 628                 u32 ipv4_nh;
 629                 struct in6_addr ipv6_nh;
 630         };
 631 };
 632
 633 struct bpf_redirect_info {
 634         u32 flags;
 635         u32 tgt_index;
 636         void *tgt_value;
 637         struct bpf_map *map;
 638         u32 kern_flags;
 639         struct bpf_nh_params nh;
 640 };
 641
 642 DECLARE_PER_CPU(struct bpf_redirect_info, bpf_redirect_info);
 643
 644 /* flags for bpf_redirect_info kern_flags */
 645 #define BPF_RI_F_RF_NO_DIRECT   BIT(0)  /* no napi_direct on return_frame */
 646
 647 /* Compute the linear packet data range [data, data_end) which
 648  * will be accessed by various program types (cls_bpf, act_bpf,
 649  * lwt, ...). Subsystems allowing direct data access must (!)
 650  * ensure that cb[] area can be written to when BPF program is
 651  * invoked (otherwise cb[] save/restore is necessary).
 652  */
 653 static inline void bpf_compute_data_pointers(struct sk_buff *skb)
 654 {
 655         struct bpf_skb_data_end *cb = (struct bpf_skb_data_end *)skb->cb;
 656
 657         BUILD_BUG_ON(sizeof(*cb) > sizeof_field(struct sk_buff, cb));
 658         cb->data_meta = skb->data - skb_metadata_len(skb);
 659         cb->data_end  = skb->data + skb_headlen(skb);
 660 }
 661
 662 /* Similar to bpf_compute_data_pointers(), except that save orginal
 663  * data in cb->data and cb->meta_data for restore.
 664  */
 665 static inline void bpf_compute_and_save_data_end(
 666         struct sk_buff *skb, void **saved_data_end)
 667 {
 668         struct bpf_skb_data_end *cb = (struct bpf_skb_data_end *)skb->cb;
 669
 670         *saved_data_end = cb->data_end;
 671         cb->data_end  = skb->data + skb_headlen(skb);
 672 }
 673
 674 /* Restore data saved by bpf_compute_data_pointers(). */
 675 static inline void bpf_restore_data_end(
 676         struct sk_buff *skb, void *saved_data_end)
 677 {
 678         struct bpf_skb_data_end *cb = (struct bpf_skb_data_end *)skb->cb;
 679
 680         cb->data_end = saved_data_end;
 681 }
 682
 683 static inline u8 *bpf_skb_cb(struct sk_buff *skb)
 684 {
 685         /* eBPF programs may read/write skb->cb[] area to transfer meta
 686          * data between tail calls. Since this also needs to work with
 687          * tc, that scratch memory is mapped to qdisc_skb_cb's data area.
 688          *
 689          * In some socket filter cases, the cb unfortunately needs to be
 690          * saved/restored so that protocol specific skb->cb[] data won't
 691          * be lost. In any case, due to unpriviledged eBPF programs
 692          * attached to sockets, we need to clear the bpf_skb_cb() area
 693          * to not leak previous contents to user space.
 694          */
 695         BUILD_BUG_ON(sizeof_field(struct __sk_buff, cb) != BPF_SKB_CB_LEN);
 696         BUILD_BUG_ON(sizeof_field(struct __sk_buff, cb) !=
 697                      sizeof_field(struct qdisc_skb_cb, data));
 698
 699         return qdisc_skb_cb(skb)->data;
 700 }
 701
 702 /* Must be invoked with migration disabled */
 703 static inline u32 __bpf_prog_run_save_cb(const struct bpf_prog *prog,
 704                                          struct sk_buff *skb)
 705 {
 706         u8 *cb_data = bpf_skb_cb(skb);
 707         u8 cb_saved[BPF_SKB_CB_LEN];
 708         u32 res;
 709
 710         if (unlikely(prog->cb_access)) {
 711                 memcpy(cb_saved, cb_data, sizeof(cb_saved));
 712                 memset(cb_data, 0, sizeof(cb_saved));
 713         }
 714
 715         res = BPF_PROG_RUN(prog, skb);
 716
 717         if (unlikely(prog->cb_access))
 718                 memcpy(cb_data, cb_saved, sizeof(cb_saved));
 719
 720         return res;
 721 }
 722
 723 static inline u32 bpf_prog_run_save_cb(const struct bpf_prog *prog,
 724                                        struct sk_buff *skb)
 725 {
 726         u32 res;
 727
 728         migrate_disable();
 729         res = __bpf_prog_run_save_cb(prog, skb);
 730         migrate_enable();
 731         return res;
 732 }
 733
 734 static inline u32 bpf_prog_run_clear_cb(const struct bpf_prog *prog,
 735                                         struct sk_buff *skb)
 736 {
 737         u8 *cb_data = bpf_skb_cb(skb);
 738         u32 res;
 739
 740         if (unlikely(prog->cb_access))
 741                 memset(cb_data, 0, BPF_SKB_CB_LEN);
 742
 743         res = bpf_prog_run_pin_on_cpu(prog, skb);
 744         return res;
 745 }
 746
 747 DECLARE_BPF_DISPATCHER(xdp)
 748
 749 static __always_inline u32 bpf_prog_run_xdp(const struct bpf_prog *prog,
 750                                             struct xdp_buff *xdp)
 751 {
 752         /* Caller needs to hold rcu_read_lock() (!), otherwise program
 753          * can be released while still running, or map elements could be
 754          * freed early while still having concurrent users. XDP fastpath
 755          * already takes rcu_read_lock() when fetching the program, so
 756          * it's not necessary here anymore.
 757          */
 758         return __BPF_PROG_RUN(prog, xdp, BPF_DISPATCHER_FUNC(xdp));
 759 }
 760
 761 void bpf_prog_change_xdp(struct bpf_prog *prev_prog, struct bpf_prog *prog);
 762
 763 static inline u32 bpf_prog_insn_size(const struct bpf_prog *prog)
 764 {
 765         return prog->len * sizeof(struct bpf_insn);
 766 }
 767
 768 static inline u32 bpf_prog_tag_scratch_size(const struct bpf_prog *prog)
 769 {
 770         return round_up(bpf_prog_insn_size(prog) +
 771                         sizeof(__be64) + 1, SHA1_BLOCK_SIZE);
 772 }
 773
 774 static inline unsigned int bpf_prog_size(unsigned int proglen)
 775 {
 776         return max(sizeof(struct bpf_prog),
 777                    offsetof(struct bpf_prog, insns[proglen]));
 778 }
 779
 780 static inline bool bpf_prog_was_classic(const struct bpf_prog *prog)
 781 {
 782         /* When classic BPF programs have been loaded and the arch
 783          * does not have a classic BPF JIT (anymore), they have been
 784          * converted via bpf_migrate_filter() to eBPF and thus always
 785          * have an unspec program type.
 786          */
 787         return prog->type == BPF_PROG_TYPE_UNSPEC;
 788 }
 789
 790 static inline u32 bpf_ctx_off_adjust_machine(u32 size)
 791 {
 792         const u32 size_machine = sizeof(unsigned long);
 793
 794         if (size > size_machine && size % size_machine == 0)
 795                 size = size_machine;
 796
 797         return size;
 798 }
 799
 800 static inline bool
 801 bpf_ctx_narrow_access_ok(u32 off, u32 size, u32 size_default)
 802 {
 803         return size <= size_default && (size & (size - 1)) == 0;
 804 }
 805
 806 static inline u8
 807 bpf_ctx_narrow_access_offset(u32 off, u32 size, u32 size_default)
 808 {
 809         u8 access_off = off & (size_default - 1);
 810
 811 #ifdef __LITTLE_ENDIAN
 812         return access_off;
 813 #else
 814         return size_default - (access_off + size);
 815 #endif
 816 }
 817
 818 #define bpf_ctx_wide_access_ok(off, size, type, field)                  \
 819         (size == sizeof(__u64) &&                                       \
 820         off >= offsetof(type, field) &&                                 \
 821         off + sizeof(__u64) <= offsetofend(type, field) &&              \
 822         off % sizeof(__u64) == 0)
 823
 824 #define bpf_classic_proglen(fprog) (fprog->len * sizeof(fprog->filter[0]))
 825
 826 static inline void bpf_prog_lock_ro(struct bpf_prog *fp)
 827 {
 828 #ifndef CONFIG_BPF_JIT_ALWAYS_ON
 829         if (!fp->jited) {
 830                 set_vm_flush_reset_perms(fp);
 831                 set_memory_ro((unsigned long)fp, fp->pages);
 832         }
 833 #endif
 834 }
 835
 836 static inline void bpf_jit_binary_lock_ro(struct bpf_binary_header *hdr)
 837 {
 838         set_vm_flush_reset_perms(hdr);
 839         set_memory_ro((unsigned long)hdr, hdr->pages);
 840         set_memory_x((unsigned long)hdr, hdr->pages);
 841 }
 842
 843 static inline struct bpf_binary_header *
 844 bpf_jit_binary_hdr(const struct bpf_prog *fp)
 845 {
 846         unsigned long real_start = (unsigned long)fp->bpf_func;
 847         unsigned long addr = real_start & PAGE_MASK;
 848
 849         return (void *)addr;
 850 }
 851
 852 int sk_filter_trim_cap(struct sock *sk, struct sk_buff *skb, unsigned int cap);
 853 static inline int sk_filter(struct sock *sk, struct sk_buff *skb)
 854 {
 855         return sk_filter_trim_cap(sk, skb, 1);
 856 }
 857
 858 struct bpf_prog *bpf_prog_select_runtime(struct bpf_prog *fp, int *err);
 859 void bpf_prog_free(struct bpf_prog *fp);
 860
 861 bool bpf_opcode_in_insntable(u8 code);
 862
 863 void bpf_prog_free_linfo(struct bpf_prog *prog);
 864 void bpf_prog_fill_jited_linfo(struct bpf_prog *prog,
 865                                const u32 *insn_to_jit_off);
 866 int bpf_prog_alloc_jited_linfo(struct bpf_prog *prog);
 867 void bpf_prog_free_jited_linfo(struct bpf_prog *prog);
 868 void bpf_prog_free_unused_jited_linfo(struct bpf_prog *prog);
 869
 870 struct bpf_prog *bpf_prog_alloc(unsigned int size, gfp_t gfp_extra_flags);
 871 struct bpf_prog *bpf_prog_alloc_no_stats(unsigned int size, gfp_t gfp_extra_flags);
 872 struct bpf_prog *bpf_prog_realloc(struct bpf_prog *fp_old, unsigned int size,
 873                                   gfp_t gfp_extra_flags);
 874 void __bpf_prog_free(struct bpf_prog *fp);
 875
 876 static inline void bpf_prog_unlock_free(struct bpf_prog *fp)
 877 {
 878         __bpf_prog_free(fp);
 879 }
 880
 881 typedef int (*bpf_aux_classic_check_t)(struct sock_filter *filter,
 882                                        unsigned int flen);
 883
 884 int bpf_prog_create(struct bpf_prog **pfp, struct sock_fprog_kern *fprog);
 885 int bpf_prog_create_from_user(struct bpf_prog **pfp, struct sock_fprog *fprog,
 886                               bpf_aux_classic_check_t trans, bool save_orig);
 887 void bpf_prog_destroy(struct bpf_prog *fp);
 888
 889 int sk_attach_filter(struct sock_fprog *fprog, struct sock *sk);
 890 int sk_attach_bpf(u32 ufd, struct sock *sk);
 891 int sk_reuseport_attach_filter(struct sock_fprog *fprog, struct sock *sk);
 892 int sk_reuseport_attach_bpf(u32 ufd, struct sock *sk);
 893 void sk_reuseport_prog_free(struct bpf_prog *prog);
 894 int sk_detach_filter(struct sock *sk);
 895 int sk_get_filter(struct sock *sk, struct sock_filter __user *filter,
 896                   unsigned int len);
 897
 898 bool sk_filter_charge(struct sock *sk, struct sk_filter *fp);
 899 void sk_filter_uncharge(struct sock *sk, struct sk_filter *fp);
 900
 901 u64 __bpf_call_base(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5);
 902 #define __bpf_call_base_args \
 903         ((u64 (*)(u64, u64, u64, u64, u64, const struct bpf_insn *)) \
 904          (void *)__bpf_call_base)
 905
 906 struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog);
 907 void bpf_jit_compile(struct bpf_prog *prog);
 908 bool bpf_jit_needs_zext(void);
 909 bool bpf_helper_changes_pkt_data(void *func);
 910
 911 static inline bool bpf_dump_raw_ok(const struct cred *cred)
 912 {
 913         /* Reconstruction of call-sites is dependent on kallsyms,
 914          * thus make dump the same restriction.
 915          */
 916         return kallsyms_show_value(cred);
 917 }
 918
 919 struct bpf_prog *bpf_patch_insn_single(struct bpf_prog *prog, u32 off,
 920                                        const struct bpf_insn *patch, u32 len);
 921 int bpf_remove_insns(struct bpf_prog *prog, u32 off, u32 cnt);
 922
 923 void bpf_clear_redirect_map(struct bpf_map *map);
 924
 925 static inline bool xdp_return_frame_no_direct(void)
 926 {
 927         struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
 928
 929         return ri->kern_flags & BPF_RI_F_RF_NO_DIRECT;
 930 }
 931
 932 static inline void xdp_set_return_frame_no_direct(void)
 933 {
 934         struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
 935
 936         ri->kern_flags |= BPF_RI_F_RF_NO_DIRECT;
 937 }
 938
 939 static inline void xdp_clear_return_frame_no_direct(void)
 940 {
 941         struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
 942
 943         ri->kern_flags &= ~BPF_RI_F_RF_NO_DIRECT;
 944 }
 945
 946 static inline int xdp_ok_fwd_dev(const struct net_device *fwd,
 947                                  unsigned int pktlen)
 948 {
 949         unsigned int len;
 950
 951         if (unlikely(!(fwd->flags & IFF_UP)))
 952                 return -ENETDOWN;
 953
 954         len = fwd->mtu + fwd->hard_header_len + VLAN_HLEN;
 955         if (pktlen > len)
 956                 return -EMSGSIZE;
 957
 958         return 0;
 959 }
 960
 961 /* The pair of xdp_do_redirect and xdp_do_flush MUST be called in the
 962  * same cpu context. Further for best results no more than a single map
 963  * for the do_redirect/do_flush pair should be used. This limitation is
 964  * because we only track one map and force a flush when the map changes.
 965  * This does not appear to be a real limitation for existing software.
 966  */
 967 int xdp_do_generic_redirect(struct net_device *dev, struct sk_buff *skb,
 968                             struct xdp_buff *xdp, struct bpf_prog *prog);
 969 int xdp_do_redirect(struct net_device *dev,
 970                     struct xdp_buff *xdp,
 971                     struct bpf_prog *prog);
 972 void xdp_do_flush(void);
 973
 974 /* The xdp_do_flush_map() helper has been renamed to drop the _map suffix, as
 975  * it is no longer only flushing maps. Keep this define for compatibility
 976  * until all drivers are updated - do not use xdp_do_flush_map() in new code!
 977  */
 978 #define xdp_do_flush_map xdp_do_flush
 979
 980 void bpf_warn_invalid_xdp_action(u32 act);
 981
 982 #ifdef CONFIG_INET
 983 struct sock *bpf_run_sk_reuseport(struct sock_reuseport *reuse, struct sock *sk,
 984                                   struct bpf_prog *prog, struct sk_buff *skb,
 985                                   u32 hash);
 986 #else
 987 static inline struct sock *
 988 bpf_run_sk_reuseport(struct sock_reuseport *reuse, struct sock *sk,
 989                      struct bpf_prog *prog, struct sk_buff *skb,
 990                      u32 hash)
 991 {
 992         return NULL;
 993 }
 994 #endif
 995
 996 #ifdef CONFIG_BPF_JIT
 997 extern int bpf_jit_enable;
 998 extern int bpf_jit_harden;
 999 extern int bpf_jit_kallsyms;
1000 extern long bpf_jit_limit;
1001 extern long bpf_jit_limit_max;
1002
1003 typedef void (*bpf_jit_fill_hole_t)(void *area, unsigned int size);
1004
1005 struct bpf_binary_header *
1006 bpf_jit_binary_alloc(unsigned int proglen, u8 **image_ptr,
1007                      unsigned int alignment,
1008                      bpf_jit_fill_hole_t bpf_fill_ill_insns);
1009 void bpf_jit_binary_free(struct bpf_binary_header *hdr);
1010 u64 bpf_jit_alloc_exec_limit(void);
1011 void *bpf_jit_alloc_exec(unsigned long size);
1012 void bpf_jit_free_exec(void *addr);
1013 void bpf_jit_free(struct bpf_prog *fp);
1014
1015 int bpf_jit_add_poke_descriptor(struct bpf_prog *prog,
1016                                 struct bpf_jit_poke_descriptor *poke);
1017
1018 int bpf_jit_get_func_addr(const struct bpf_prog *prog,
1019                           const struct bpf_insn *insn, bool extra_pass,
1020                           u64 *func_addr, bool *func_addr_fixed);
1021
1022 struct bpf_prog *bpf_jit_blind_constants(struct bpf_prog *fp);
1023 void bpf_jit_prog_release_other(struct bpf_prog *fp, struct bpf_prog *fp_other);
1024
1025 static inline void bpf_jit_dump(unsigned int flen, unsigned int proglen,
1026                                 u32 pass, void *image)
1027 {
1028         pr_err("flen=%u proglen=%u pass=%u image=%pK from=%s pid=%d\n", flen,
1029                proglen, pass, image, current->comm, task_pid_nr(current));
1030
1031         if (image)
1032                 print_hex_dump(KERN_ERR, "JIT code: ", DUMP_PREFIX_OFFSET,
1033                                16, 1, image, proglen, false);
1034 }
1035
1036 static inline bool bpf_jit_is_ebpf(void)
1037 {
1038 # ifdef CONFIG_HAVE_EBPF_JIT
1039         return true;
1040 # else
1041         return false;
1042 # endif
1043 }
1044
1045 static inline bool ebpf_jit_enabled(void)
1046 {
1047         return bpf_jit_enable && bpf_jit_is_ebpf();
1048 }
1049
1050 static inline bool bpf_prog_ebpf_jited(const struct bpf_prog *fp)
1051 {
1052         return fp->jited && bpf_jit_is_ebpf();
1053 }
1054
1055 static inline bool bpf_jit_blinding_enabled(struct bpf_prog *prog)
1056 {
1057         /* These are the prerequisites, should someone ever have the
1058          * idea to call blinding outside of them, we make sure to
1059          * bail out.
1060          */
1061         if (!bpf_jit_is_ebpf())
1062                 return false;
1063         if (!prog->jit_requested)
1064                 return false;
1065         if (!bpf_jit_harden)
1066                 return false;
1067         if (bpf_jit_harden == 1 && capable(CAP_SYS_ADMIN))
1068                 return false;
1069
1070         return true;
1071 }
1072
1073 static inline bool bpf_jit_kallsyms_enabled(void)
1074 {
1075         /* There are a couple of corner cases where kallsyms should
1076          * not be enabled f.e. on hardening.
1077          */
1078         if (bpf_jit_harden)
1079                 return false;
1080         if (!bpf_jit_kallsyms)
1081                 return false;
1082         if (bpf_jit_kallsyms == 1)
1083                 return true;
1084
1085         return false;
1086 }
1087
1088 const char *__bpf_address_lookup(unsigned long addr, unsigned long *size,
1089                                  unsigned long *off, char *sym);
1090 bool is_bpf_text_address(unsigned long addr);
1091 int bpf_get_kallsym(unsigned int symnum, unsigned long *value, char *type,
1092                     char *sym);
1093
1094 static inline const char *
1095 bpf_address_lookup(unsigned long addr, unsigned long *size,
1096                    unsigned long *off, char **modname, char *sym)
1097 {
1098         const char *ret = __bpf_address_lookup(addr, size, off, sym);
1099
1100         if (ret && modname)
1101                 *modname = NULL;
1102         return ret;
1103 }
1104
1105 void bpf_prog_kallsyms_add(struct bpf_prog *fp);
1106 void bpf_prog_kallsyms_del(struct bpf_prog *fp);
1107
1108 #else /* CONFIG_BPF_JIT */
1109
1110 static inline bool ebpf_jit_enabled(void)
1111 {
1112         return false;
1113 }
1114
1115 static inline bool bpf_jit_blinding_enabled(struct bpf_prog *prog)
1116 {
1117         return false;
1118 }
1119
1120 static inline bool bpf_prog_ebpf_jited(const struct bpf_prog *fp)
1121 {
1122         return false;
1123 }
1124
1125 static inline int
1126 bpf_jit_add_poke_descriptor(struct bpf_prog *prog,
1127                             struct bpf_jit_poke_descriptor *poke)
1128 {
1129         return -ENOTSUPP;
1130 }
1131
1132 static inline void bpf_jit_free(struct bpf_prog *fp)
1133 {
1134         bpf_prog_unlock_free(fp);
1135 }
1136
1137 static inline bool bpf_jit_kallsyms_enabled(void)
1138 {
1139         return false;
1140 }
1141
1142 static inline const char *
1143 __bpf_address_lookup(unsigned long addr, unsigned long *size,
1144                      unsigned long *off, char *sym)
1145 {
1146         return NULL;
1147 }
1148
1149 static inline bool is_bpf_text_address(unsigned long addr)
1150 {
1151         return false;
1152 }
1153
1154 static inline int bpf_get_kallsym(unsigned int symnum, unsigned long *value,
1155                                   char *type, char *sym)
1156 {
1157         return -ERANGE;
1158 }
1159
1160 static inline const char *
1161 bpf_address_lookup(unsigned long addr, unsigned long *size,
1162                    unsigned long *off, char **modname, char *sym)
1163 {
1164         return NULL;
1165 }
1166
1167 static inline void bpf_prog_kallsyms_add(struct bpf_prog *fp)
1168 {
1169 }
1170
1171 static inline void bpf_prog_kallsyms_del(struct bpf_prog *fp)
1172 {
1173 }
1174
1175 #endif /* CONFIG_BPF_JIT */
1176
1177 void bpf_prog_kallsyms_del_all(struct bpf_prog *fp);
1178
1179 #define BPF_ANC         BIT(15)
1180
1181 static inline bool bpf_needs_clear_a(const struct sock_filter *first)
1182 {
1183         switch (first->code) {
1184         case BPF_RET | BPF_K:
1185         case BPF_LD | BPF_W | BPF_LEN:
1186                 return false;
1187
1188         case BPF_LD | BPF_W | BPF_ABS:
1189         case BPF_LD | BPF_H | BPF_ABS:
1190         case BPF_LD | BPF_B | BPF_ABS:
1191                 if (first->k == SKF_AD_OFF + SKF_AD_ALU_XOR_X)
1192                         return true;
1193                 return false;
1194
1195         default:
1196                 return true;
1197         }
1198 }
1199
1200 static inline u16 bpf_anc_helper(const struct sock_filter *ftest)
1201 {
1202         BUG_ON(ftest->code & BPF_ANC);
1203
1204         switch (ftest->code) {
1205         case BPF_LD | BPF_W | BPF_ABS:
1206         case BPF_LD | BPF_H | BPF_ABS:
1207         case BPF_LD | BPF_B | BPF_ABS:
1208 #define BPF_ANCILLARY(CODE)     case SKF_AD_OFF + SKF_AD_##CODE:        \
1209                                 return BPF_ANC | SKF_AD_##CODE
1210                 switch (ftest->k) {
1211                 BPF_ANCILLARY(PROTOCOL);
1212                 BPF_ANCILLARY(PKTTYPE);
1213                 BPF_ANCILLARY(IFINDEX);
1214                 BPF_ANCILLARY(NLATTR);
1215                 BPF_ANCILLARY(NLATTR_NEST);
1216                 BPF_ANCILLARY(MARK);
1217                 BPF_ANCILLARY(QUEUE);
1218                 BPF_ANCILLARY(HATYPE);
1219                 BPF_ANCILLARY(RXHASH);
1220                 BPF_ANCILLARY(CPU);
1221                 BPF_ANCILLARY(ALU_XOR_X);
1222                 BPF_ANCILLARY(VLAN_TAG);
1223                 BPF_ANCILLARY(VLAN_TAG_PRESENT);
1224                 BPF_ANCILLARY(PAY_OFFSET);
1225                 BPF_ANCILLARY(RANDOM);
1226                 BPF_ANCILLARY(VLAN_TPID);
1227                 }
1228                 fallthrough;
1229         default:
1230                 return ftest->code;
1231         }
1232 }
1233
1234 void *bpf_internal_load_pointer_neg_helper(const struct sk_buff *skb,
1235                                            int k, unsigned int size);
1236
1237 static inline void *bpf_load_pointer(const struct sk_buff *skb, int k,
1238                                      unsigned int size, void *buffer)
1239 {
1240         if (k >= 0)
1241                 return skb_header_pointer(skb, k, size, buffer);
1242
1243         return bpf_internal_load_pointer_neg_helper(skb, k, size);
1244 }
1245
1246 static inline int bpf_tell_extensions(void)
1247 {
1248         return SKF_AD_MAX;
1249 }
1250
1251 struct bpf_sock_addr_kern {
1252         struct sock *sk;
1253         struct sockaddr *uaddr;
1254         /* Temporary "register" to make indirect stores to nested structures
1255          * defined above. We need three registers to make such a store, but
1256          * only two (src and dst) are available at convert_ctx_access time
1257          */
1258         u64 tmp_reg;
1259         void *t_ctx;    /* Attach type specific context. */
1260 };
1261
1262 struct bpf_sock_ops_kern {
1263         struct  sock *sk;
1264         union {
1265                 u32 args[4];
1266                 u32 reply;
1267                 u32 replylong[4];
1268         };
1269         struct sk_buff  *syn_skb;
1270         struct sk_buff  *skb;
1271         void    *skb_data_end;
1272         u8      op;
1273         u8      is_fullsock;
1274         u8      remaining_opt_len;
1275         u64     temp;                   /* temp and everything after is not
1276                                          * initialized to 0 before calling
1277                                          * the BPF program. New fields that
1278                                          * should be initialized to 0 should
1279                                          * be inserted before temp.
1280                                          * temp is scratch storage used by
1281                                          * sock_ops_convert_ctx_access
1282                                          * as temporary storage of a register.
1283                                          */
1284 };
1285
1286 struct bpf_sysctl_kern {
1287         struct ctl_table_header *head;
1288         struct ctl_table *table;
1289         void *cur_val;
1290         size_t cur_len;
1291         void *new_val;
1292         size_t new_len;
1293         int new_updated;
1294         int write;
1295         loff_t *ppos;
1296         /* Temporary "register" for indirect stores to ppos. */
1297         u64 tmp_reg;
1298 };
1299
1300 struct bpf_sockopt_kern {
1301         struct sock     *sk;
1302         u8              *optval;
1303         u8              *optval_end;
1304         s32             level;
1305         s32             optname;
1306         s32             optlen;
1307         s32             retval;
1308 };
1309
1310 int copy_bpf_fprog_from_user(struct sock_fprog *dst, sockptr_t src, int len);
1311
1312 struct bpf_sk_lookup_kern {
1313         u16             family;
1314         u16             protocol;
1315         __be16          sport;
1316         u16             dport;
1317         struct {
1318                 __be32 saddr;
1319                 __be32 daddr;
1320         } v4;
1321         struct {
1322                 const struct in6_addr *saddr;
1323                 const struct in6_addr *daddr;
1324         } v6;
1325         struct sock     *selected_sk;
1326         bool            no_reuseport;
1327 };
1328
1329 extern struct static_key_false bpf_sk_lookup_enabled;
1330
1331 /* Runners for BPF_SK_LOOKUP programs to invoke on socket lookup.
1332  *
1333  * Allowed return values for a BPF SK_LOOKUP program are SK_PASS and
1334  * SK_DROP. Their meaning is as follows:
1335  *
1336  *  SK_PASS && ctx.selected_sk != NULL: use selected_sk as lookup result
1337  *  SK_PASS && ctx.selected_sk == NULL: continue to htable-based socket lookup
1338  *  SK_DROP                           : terminate lookup with -ECONNREFUSED
1339  *
1340  * This macro aggregates return values and selected sockets from
1341  * multiple BPF programs according to following rules in order:
1342  *
1343  *  1. If any program returned SK_PASS and a non-NULL ctx.selected_sk,
1344  *     macro result is SK_PASS and last ctx.selected_sk is used.
1345  *  2. If any program returned SK_DROP return value,
1346  *     macro result is SK_DROP.
1347  *  3. Otherwise result is SK_PASS and ctx.selected_sk is NULL.
1348  *
1349  * Caller must ensure that the prog array is non-NULL, and that the
1350  * array as well as the programs it contains remain valid.
1351  */
1352 #define BPF_PROG_SK_LOOKUP_RUN_ARRAY(array, ctx, func)                  \
1353         ({                                                              \
1354                 struct bpf_sk_lookup_kern *_ctx = &(ctx);               \
1355                 struct bpf_prog_array_item *_item;                      \
1356                 struct sock *_selected_sk = NULL;                       \
1357                 bool _no_reuseport = false;                             \
1358                 struct bpf_prog *_prog;                                 \
1359                 bool _all_pass = true;                                  \
1360                 u32 _ret;                                               \
1361                                                                         \
1362                 migrate_disable();                                      \
1363                 _item = &(array)->items[0];                             \
1364                 while ((_prog = READ_ONCE(_item->prog))) {              \
1365                         /* restore most recent selection */             \
1366                         _ctx->selected_sk = _selected_sk;               \
1367                         _ctx->no_reuseport = _no_reuseport;             \
1368                                                                         \
1369                         _ret = func(_prog, _ctx);                       \
1370                         if (_ret == SK_PASS && _ctx->selected_sk) {     \
1371                                 /* remember last non-NULL socket */     \
1372                                 _selected_sk = _ctx->selected_sk;       \
1373                                 _no_reuseport = _ctx->no_reuseport;     \
1374                         } else if (_ret == SK_DROP && _all_pass) {      \
1375                                 _all_pass = false;                      \
1376                         }                                               \
1377                         _item++;                                        \
1378                 }                                                       \
1379                 _ctx->selected_sk = _selected_sk;                       \
1380                 _ctx->no_reuseport = _no_reuseport;                     \
1381                 migrate_enable();                                       \
1382                 _all_pass || _selected_sk ? SK_PASS : SK_DROP;          \
1383          })
1384
1385 static inline bool bpf_sk_lookup_run_v4(struct net *net, int protocol,
1386                                         const __be32 saddr, const __be16 sport,
1387                                         const __be32 daddr, const u16 dport,
1388                                         struct sock **psk)
1389 {
1390         struct bpf_prog_array *run_array;
1391         struct sock *selected_sk = NULL;
1392         bool no_reuseport = false;
1393
1394         rcu_read_lock();
1395         run_array = rcu_dereference(net->bpf.run_array[NETNS_BPF_SK_LOOKUP]);
1396         if (run_array) {
1397                 struct bpf_sk_lookup_kern ctx = {
1398                         .family         = AF_INET,
1399                         .protocol       = protocol,
1400                         .v4.saddr       = saddr,
1401                         .v4.daddr       = daddr,
1402                         .sport          = sport,
1403                         .dport          = dport,
1404                 };
1405                 u32 act;
1406
1407                 act = BPF_PROG_SK_LOOKUP_RUN_ARRAY(run_array, ctx, BPF_PROG_RUN);
1408                 if (act == SK_PASS) {
1409                         selected_sk = ctx.selected_sk;
1410                         no_reuseport = ctx.no_reuseport;
1411                 } else {
1412                         selected_sk = ERR_PTR(-ECONNREFUSED);
1413                 }
1414         }
1415         rcu_read_unlock();
1416         *psk = selected_sk;
1417         return no_reuseport;
1418 }
1419
1420 #if IS_ENABLED(CONFIG_IPV6)
1421 static inline bool bpf_sk_lookup_run_v6(struct net *net, int protocol,
1422                                         const struct in6_addr *saddr,
1423                                         const __be16 sport,
1424                                         const struct in6_addr *daddr,
1425                                         const u16 dport,
1426                                         struct sock **psk)
1427 {
1428         struct bpf_prog_array *run_array;
1429         struct sock *selected_sk = NULL;
1430         bool no_reuseport = false;
1431
1432         rcu_read_lock();
1433         run_array = rcu_dereference(net->bpf.run_array[NETNS_BPF_SK_LOOKUP]);
1434         if (run_array) {
1435                 struct bpf_sk_lookup_kern ctx = {
1436                         .family         = AF_INET6,
1437                         .protocol       = protocol,
1438                         .v6.saddr       = saddr,
1439                         .v6.daddr       = daddr,
1440                         .sport          = sport,
1441                         .dport          = dport,
1442                 };
1443                 u32 act;
1444
1445                 act = BPF_PROG_SK_LOOKUP_RUN_ARRAY(run_array, ctx, BPF_PROG_RUN);
1446                 if (act == SK_PASS) {
1447                         selected_sk = ctx.selected_sk;
1448                         no_reuseport = ctx.no_reuseport;
1449                 } else {
1450                         selected_sk = ERR_PTR(-ECONNREFUSED);
1451                 }
1452         }
1453         rcu_read_unlock();
1454         *psk = selected_sk;
1455         return no_reuseport;
1456 }
1457 #endif /* IS_ENABLED(CONFIG_IPV6) */
1458
1459 #endif /* __LINUX_FILTER_H__ */