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 #include <linux/u64_stats_sync.h>
  26
  27 #include <net/sch_generic.h>
  28
  29 #include <asm/byteorder.h>
  30 #include <uapi/linux/filter.h>
  31 #include <uapi/linux/bpf.h>
  32
  33 struct sk_buff;
  34 struct sock;
  35 struct seccomp_data;
  36 struct bpf_prog_aux;
  37 struct xdp_rxq_info;
  38 struct xdp_buff;
  39 struct sock_reuseport;
  40 struct ctl_table;
  41 struct ctl_table_header;
  42
  43 /* ArgX, context and stack frame pointer register positions. Note,
  44  * Arg1, Arg2, Arg3, etc are used as argument mappings of function
  45  * calls in BPF_CALL instruction.
  46  */
  47 #define BPF_REG_ARG1    BPF_REG_1
  48 #define BPF_REG_ARG2    BPF_REG_2
  49 #define BPF_REG_ARG3    BPF_REG_3
  50 #define BPF_REG_ARG4    BPF_REG_4
  51 #define BPF_REG_ARG5    BPF_REG_5
  52 #define BPF_REG_CTX     BPF_REG_6
  53 #define BPF_REG_FP      BPF_REG_10
  54
  55 /* Additional register mappings for converted user programs. */
  56 #define BPF_REG_A       BPF_REG_0
  57 #define BPF_REG_X       BPF_REG_7
  58 #define BPF_REG_TMP     BPF_REG_2       /* scratch reg */
  59 #define BPF_REG_D       BPF_REG_8       /* data, callee-saved */
  60 #define BPF_REG_H       BPF_REG_9       /* hlen, callee-saved */
  61
  62 /* Kernel hidden auxiliary/helper register. */
  63 #define BPF_REG_AX              MAX_BPF_REG
  64 #define MAX_BPF_EXT_REG         (MAX_BPF_REG + 1)
  65 #define MAX_BPF_JIT_REG         MAX_BPF_EXT_REG
  66
  67 /* unused opcode to mark special call to bpf_tail_call() helper */
  68 #define BPF_TAIL_CALL   0xf0
  69
  70 /* unused opcode to mark special load instruction. Same as BPF_ABS */
  71 #define BPF_PROBE_MEM   0x20
  72
  73 /* unused opcode to mark call to interpreter with arguments */
  74 #define BPF_CALL_ARGS   0xe0
  75
  76 /* unused opcode to mark speculation barrier for mitigating
  77  * Speculative Store Bypass
  78  */
  79 #define BPF_NOSPEC      0xc0
  80
  81 /* As per nm, we expose JITed images as text (code) section for
  82  * kallsyms. That way, tools like perf can find it to match
  83  * addresses.
  84  */
  85 #define BPF_SYM_ELF_TYPE        't'
  86
  87 /* BPF program can access up to 512 bytes of stack space. */
  88 #define MAX_BPF_STACK   512
  89
  90 /* Helper macros for filter block array initializers. */
  91
  92 /* ALU ops on registers, bpf_add|sub|...: dst_reg += src_reg */
  93
  94 #define BPF_ALU64_REG(OP, DST, SRC)                             \
  95         ((struct bpf_insn) {                                    \
  96                 .code  = BPF_ALU64 | BPF_OP(OP) | BPF_X,        \
  97                 .dst_reg = DST,                                 \
  98                 .src_reg = SRC,                                 \
  99                 .off   = 0,                                     \
 100                 .imm   = 0 })
 101
 102 #define BPF_ALU32_REG(OP, DST, SRC)                             \
 103         ((struct bpf_insn) {                                    \
 104                 .code  = BPF_ALU | BPF_OP(OP) | BPF_X,          \
 105                 .dst_reg = DST,                                 \
 106                 .src_reg = SRC,                                 \
 107                 .off   = 0,                                     \
 108                 .imm   = 0 })
 109
 110 /* ALU ops on immediates, bpf_add|sub|...: dst_reg += imm32 */
 111
 112 #define BPF_ALU64_IMM(OP, DST, IMM)                             \
 113         ((struct bpf_insn) {                                    \
 114                 .code  = BPF_ALU64 | BPF_OP(OP) | BPF_K,        \
 115                 .dst_reg = DST,                                 \
 116                 .src_reg = 0,                                   \
 117                 .off   = 0,                                     \
 118                 .imm   = IMM })
 119
 120 #define BPF_ALU32_IMM(OP, DST, IMM)                             \
 121         ((struct bpf_insn) {                                    \
 122                 .code  = BPF_ALU | BPF_OP(OP) | BPF_K,          \
 123                 .dst_reg = DST,                                 \
 124                 .src_reg = 0,                                   \
 125                 .off   = 0,                                     \
 126                 .imm   = IMM })
 127
 128 /* Endianess conversion, cpu_to_{l,b}e(), {l,b}e_to_cpu() */
 129
 130 #define BPF_ENDIAN(TYPE, DST, LEN)                              \
 131         ((struct bpf_insn) {                                    \
 132                 .code  = BPF_ALU | BPF_END | BPF_SRC(TYPE),     \
 133                 .dst_reg = DST,                                 \
 134                 .src_reg = 0,                                   \
 135                 .off   = 0,                                     \
 136                 .imm   = LEN })
 137
 138 /* Short form of mov, dst_reg = src_reg */
 139
 140 #define BPF_MOV64_REG(DST, SRC)                                 \
 141         ((struct bpf_insn) {                                    \
 142                 .code  = BPF_ALU64 | BPF_MOV | BPF_X,           \
 143                 .dst_reg = DST,                                 \
 144                 .src_reg = SRC,                                 \
 145                 .off   = 0,                                     \
 146                 .imm   = 0 })
 147
 148 #define BPF_MOV32_REG(DST, SRC)                                 \
 149         ((struct bpf_insn) {                                    \
 150                 .code  = BPF_ALU | BPF_MOV | BPF_X,             \
 151                 .dst_reg = DST,                                 \
 152                 .src_reg = SRC,                                 \
 153                 .off   = 0,                                     \
 154                 .imm   = 0 })
 155
 156 /* Short form of mov, dst_reg = imm32 */
 157
 158 #define BPF_MOV64_IMM(DST, IMM)                                 \
 159         ((struct bpf_insn) {                                    \
 160                 .code  = BPF_ALU64 | BPF_MOV | BPF_K,           \
 161                 .dst_reg = DST,                                 \
 162                 .src_reg = 0,                                   \
 163                 .off   = 0,                                     \
 164                 .imm   = IMM })
 165
 166 #define BPF_MOV32_IMM(DST, IMM)                                 \
 167         ((struct bpf_insn) {                                    \
 168                 .code  = BPF_ALU | BPF_MOV | BPF_K,             \
 169                 .dst_reg = DST,                                 \
 170                 .src_reg = 0,                                   \
 171                 .off   = 0,                                     \
 172                 .imm   = IMM })
 173
 174 /* Special form of mov32, used for doing explicit zero extension on dst. */
 175 #define BPF_ZEXT_REG(DST)                                       \
 176         ((struct bpf_insn) {                                    \
 177                 .code  = BPF_ALU | BPF_MOV | BPF_X,             \
 178                 .dst_reg = DST,                                 \
 179                 .src_reg = DST,                                 \
 180                 .off   = 0,                                     \
 181                 .imm   = 1 })
 182
 183 static inline bool insn_is_zext(const struct bpf_insn *insn)
 184 {
 185         return insn->code == (BPF_ALU | BPF_MOV | BPF_X) && insn->imm == 1;
 186 }
 187
 188 /* BPF_LD_IMM64 macro encodes single 'load 64-bit immediate' insn */
 189 #define BPF_LD_IMM64(DST, IMM)                                  \
 190         BPF_LD_IMM64_RAW(DST, 0, IMM)
 191
 192 #define BPF_LD_IMM64_RAW(DST, SRC, IMM)                         \
 193         ((struct bpf_insn) {                                    \
 194                 .code  = BPF_LD | BPF_DW | BPF_IMM,             \
 195                 .dst_reg = DST,                                 \
 196                 .src_reg = SRC,                                 \
 197                 .off   = 0,                                     \
 198                 .imm   = (__u32) (IMM) }),                      \
 199         ((struct bpf_insn) {                                    \
 200                 .code  = 0, /* zero is reserved opcode */       \
 201                 .dst_reg = 0,                                   \
 202                 .src_reg = 0,                                   \
 203                 .off   = 0,                                     \
 204                 .imm   = ((__u64) (IMM)) >> 32 })
 205
 206 /* pseudo BPF_LD_IMM64 insn used to refer to process-local map_fd */
 207 #define BPF_LD_MAP_FD(DST, MAP_FD)                              \
 208         BPF_LD_IMM64_RAW(DST, BPF_PSEUDO_MAP_FD, MAP_FD)
 209
 210 /* Short form of mov based on type, BPF_X: dst_reg = src_reg, BPF_K: dst_reg = imm32 */
 211
 212 #define BPF_MOV64_RAW(TYPE, DST, SRC, IMM)                      \
 213         ((struct bpf_insn) {                                    \
 214                 .code  = BPF_ALU64 | BPF_MOV | BPF_SRC(TYPE),   \
 215                 .dst_reg = DST,                                 \
 216                 .src_reg = SRC,                                 \
 217                 .off   = 0,                                     \
 218                 .imm   = IMM })
 219
 220 #define BPF_MOV32_RAW(TYPE, DST, SRC, IMM)                      \
 221         ((struct bpf_insn) {                                    \
 222                 .code  = BPF_ALU | BPF_MOV | BPF_SRC(TYPE),     \
 223                 .dst_reg = DST,                                 \
 224                 .src_reg = SRC,                                 \
 225                 .off   = 0,                                     \
 226                 .imm   = IMM })
 227
 228 /* Direct packet access, R0 = *(uint *) (skb->data + imm32) */
 229
 230 #define BPF_LD_ABS(SIZE, IMM)                                   \
 231         ((struct bpf_insn) {                                    \
 232                 .code  = BPF_LD | BPF_SIZE(SIZE) | BPF_ABS,     \
 233                 .dst_reg = 0,                                   \
 234                 .src_reg = 0,                                   \
 235                 .off   = 0,                                     \
 236                 .imm   = IMM })
 237
 238 /* Indirect packet access, R0 = *(uint *) (skb->data + src_reg + imm32) */
 239
 240 #define BPF_LD_IND(SIZE, SRC, IMM)                              \
 241         ((struct bpf_insn) {                                    \
 242                 .code  = BPF_LD | BPF_SIZE(SIZE) | BPF_IND,     \
 243                 .dst_reg = 0,                                   \
 244                 .src_reg = SRC,                                 \
 245                 .off   = 0,                                     \
 246                 .imm   = IMM })
 247
 248 /* Memory load, dst_reg = *(uint *) (src_reg + off16) */
 249
 250 #define BPF_LDX_MEM(SIZE, DST, SRC, OFF)                        \
 251         ((struct bpf_insn) {                                    \
 252                 .code  = BPF_LDX | BPF_SIZE(SIZE) | BPF_MEM,    \
 253                 .dst_reg = DST,                                 \
 254                 .src_reg = SRC,                                 \
 255                 .off   = OFF,                                   \
 256                 .imm   = 0 })
 257
 258 /* Memory store, *(uint *) (dst_reg + off16) = src_reg */
 259
 260 #define BPF_STX_MEM(SIZE, DST, SRC, OFF)                        \
 261         ((struct bpf_insn) {                                    \
 262                 .code  = BPF_STX | BPF_SIZE(SIZE) | BPF_MEM,    \
 263                 .dst_reg = DST,                                 \
 264                 .src_reg = SRC,                                 \
 265                 .off   = OFF,                                   \
 266                 .imm   = 0 })
 267
 268
 269 /*
 270  * Atomic operations:
 271  *
 272  *   BPF_ADD                  *(uint *) (dst_reg + off16) += src_reg
 273  *   BPF_AND                  *(uint *) (dst_reg + off16) &= src_reg
 274  *   BPF_OR                   *(uint *) (dst_reg + off16) |= src_reg
 275  *   BPF_XOR                  *(uint *) (dst_reg + off16) ^= src_reg
 276  *   BPF_ADD | BPF_FETCH      src_reg = atomic_fetch_add(dst_reg + off16, src_reg);
 277  *   BPF_AND | BPF_FETCH      src_reg = atomic_fetch_and(dst_reg + off16, src_reg);
 278  *   BPF_OR | BPF_FETCH       src_reg = atomic_fetch_or(dst_reg + off16, src_reg);
 279  *   BPF_XOR | BPF_FETCH      src_reg = atomic_fetch_xor(dst_reg + off16, src_reg);
 280  *   BPF_XCHG                 src_reg = atomic_xchg(dst_reg + off16, src_reg)
 281  *   BPF_CMPXCHG              r0 = atomic_cmpxchg(dst_reg + off16, r0, src_reg)
 282  */
 283
 284 #define BPF_ATOMIC_OP(SIZE, OP, DST, SRC, OFF)                  \
 285         ((struct bpf_insn) {                                    \
 286                 .code  = BPF_STX | BPF_SIZE(SIZE) | BPF_ATOMIC, \
 287                 .dst_reg = DST,                                 \
 288                 .src_reg = SRC,                                 \
 289                 .off   = OFF,                                   \
 290                 .imm   = OP })
 291
 292 /* Legacy alias */
 293 #define BPF_STX_XADD(SIZE, DST, SRC, OFF) BPF_ATOMIC_OP(SIZE, BPF_ADD, DST, SRC, OFF)
 294
 295 /* Memory store, *(uint *) (dst_reg + off16) = imm32 */
 296
 297 #define BPF_ST_MEM(SIZE, DST, OFF, IMM)                         \
 298         ((struct bpf_insn) {                                    \
 299                 .code  = BPF_ST | BPF_SIZE(SIZE) | BPF_MEM,     \
 300                 .dst_reg = DST,                                 \
 301                 .src_reg = 0,                                   \
 302                 .off   = OFF,                                   \
 303                 .imm   = IMM })
 304
 305 /* Conditional jumps against registers, if (dst_reg 'op' src_reg) goto pc + off16 */
 306
 307 #define BPF_JMP_REG(OP, DST, SRC, OFF)                          \
 308         ((struct bpf_insn) {                                    \
 309                 .code  = BPF_JMP | BPF_OP(OP) | BPF_X,          \
 310                 .dst_reg = DST,                                 \
 311                 .src_reg = SRC,                                 \
 312                 .off   = OFF,                                   \
 313                 .imm   = 0 })
 314
 315 /* Conditional jumps against immediates, if (dst_reg 'op' imm32) goto pc + off16 */
 316
 317 #define BPF_JMP_IMM(OP, DST, IMM, OFF)                          \
 318         ((struct bpf_insn) {                                    \
 319                 .code  = BPF_JMP | BPF_OP(OP) | BPF_K,          \
 320                 .dst_reg = DST,                                 \
 321                 .src_reg = 0,                                   \
 322                 .off   = OFF,                                   \
 323                 .imm   = IMM })
 324
 325 /* Like BPF_JMP_REG, but with 32-bit wide operands for comparison. */
 326
 327 #define BPF_JMP32_REG(OP, DST, SRC, OFF)                        \
 328         ((struct bpf_insn) {                                    \
 329                 .code  = BPF_JMP32 | BPF_OP(OP) | BPF_X,        \
 330                 .dst_reg = DST,                                 \
 331                 .src_reg = SRC,                                 \
 332                 .off   = OFF,                                   \
 333                 .imm   = 0 })
 334
 335 /* Like BPF_JMP_IMM, but with 32-bit wide operands for comparison. */
 336
 337 #define BPF_JMP32_IMM(OP, DST, IMM, OFF)                        \
 338         ((struct bpf_insn) {                                    \
 339                 .code  = BPF_JMP32 | BPF_OP(OP) | BPF_K,        \
 340                 .dst_reg = DST,                                 \
 341                 .src_reg = 0,                                   \
 342                 .off   = OFF,                                   \
 343                 .imm   = IMM })
 344
 345 /* Unconditional jumps, goto pc + off16 */
 346
 347 #define BPF_JMP_A(OFF)                                          \
 348         ((struct bpf_insn) {                                    \
 349                 .code  = BPF_JMP | BPF_JA,                      \
 350                 .dst_reg = 0,                                   \
 351                 .src_reg = 0,                                   \
 352                 .off   = OFF,                                   \
 353                 .imm   = 0 })
 354
 355 /* Relative call */
 356
 357 #define BPF_CALL_REL(TGT)                                       \
 358         ((struct bpf_insn) {                                    \
 359                 .code  = BPF_JMP | BPF_CALL,                    \
 360                 .dst_reg = 0,                                   \
 361                 .src_reg = BPF_PSEUDO_CALL,                     \
 362                 .off   = 0,                                     \
 363                 .imm   = TGT })
 364
 365 /* Function call */
 366
 367 #define BPF_CAST_CALL(x)                                        \
 368                 ((u64 (*)(u64, u64, u64, u64, u64))(x))
 369
 370 #define BPF_EMIT_CALL(FUNC)                                     \
 371         ((struct bpf_insn) {                                    \
 372                 .code  = BPF_JMP | BPF_CALL,                    \
 373                 .dst_reg = 0,                                   \
 374                 .src_reg = 0,                                   \
 375                 .off   = 0,                                     \
 376                 .imm   = ((FUNC) - __bpf_call_base) })
 377
 378 /* Raw code statement block */
 379
 380 #define BPF_RAW_INSN(CODE, DST, SRC, OFF, IMM)                  \
 381         ((struct bpf_insn) {                                    \
 382                 .code  = CODE,                                  \
 383                 .dst_reg = DST,                                 \
 384                 .src_reg = SRC,                                 \
 385                 .off   = OFF,                                   \
 386                 .imm   = IMM })
 387
 388 /* Program exit */
 389
 390 #define BPF_EXIT_INSN()                                         \
 391         ((struct bpf_insn) {                                    \
 392                 .code  = BPF_JMP | BPF_EXIT,                    \
 393                 .dst_reg = 0,                                   \
 394                 .src_reg = 0,                                   \
 395                 .off   = 0,                                     \
 396                 .imm   = 0 })
 397
 398 /* Speculation barrier */
 399
 400 #define BPF_ST_NOSPEC()                                         \
 401         ((struct bpf_insn) {                                    \
 402                 .code  = BPF_ST | BPF_NOSPEC,                   \
 403                 .dst_reg = 0,                                   \
 404                 .src_reg = 0,                                   \
 405                 .off   = 0,                                     \
 406                 .imm   = 0 })
 407
 408 /* Internal classic blocks for direct assignment */
 409
 410 #define __BPF_STMT(CODE, K)                                     \
 411         ((struct sock_filter) BPF_STMT(CODE, K))
 412
 413 #define __BPF_JUMP(CODE, K, JT, JF)                             \
 414         ((struct sock_filter) BPF_JUMP(CODE, K, JT, JF))
 415
 416 #define bytes_to_bpf_size(bytes)                                \
 417 ({                                                              \
 418         int bpf_size = -EINVAL;                                 \
 419                                                                 \
 420         if (bytes == sizeof(u8))                                \
 421                 bpf_size = BPF_B;                               \
 422         else if (bytes == sizeof(u16))                          \
 423                 bpf_size = BPF_H;                               \
 424         else if (bytes == sizeof(u32))                          \
 425                 bpf_size = BPF_W;                               \
 426         else if (bytes == sizeof(u64))                          \
 427                 bpf_size = BPF_DW;                              \
 428                                                                 \
 429         bpf_size;                                               \
 430 })
 431
 432 #define bpf_size_to_bytes(bpf_size)                             \
 433 ({                                                              \
 434         int bytes = -EINVAL;                                    \
 435                                                                 \
 436         if (bpf_size == BPF_B)                                  \
 437                 bytes = sizeof(u8);                             \
 438         else if (bpf_size == BPF_H)                             \
 439                 bytes = sizeof(u16);                            \
 440         else if (bpf_size == BPF_W)                             \
 441                 bytes = sizeof(u32);                            \
 442         else if (bpf_size == BPF_DW)                            \
 443                 bytes = sizeof(u64);                            \
 444                                                                 \
 445         bytes;                                                  \
 446 })
 447
 448 #define BPF_SIZEOF(type)                                        \
 449         ({                                                      \
 450                 const int __size = bytes_to_bpf_size(sizeof(type)); \
 451                 BUILD_BUG_ON(__size < 0);                       \
 452                 __size;                                         \
 453         })
 454
 455 #define BPF_FIELD_SIZEOF(type, field)                           \
 456         ({                                                      \
 457                 const int __size = bytes_to_bpf_size(sizeof_field(type, field)); \
 458                 BUILD_BUG_ON(__size < 0);                       \
 459                 __size;                                         \
 460         })
 461
 462 #define BPF_LDST_BYTES(insn)                                    \
 463         ({                                                      \
 464                 const int __size = bpf_size_to_bytes(BPF_SIZE((insn)->code)); \
 465                 WARN_ON(__size < 0);                            \
 466                 __size;                                         \
 467         })
 468
 469 #define __BPF_MAP_0(m, v, ...) v
 470 #define __BPF_MAP_1(m, v, t, a, ...) m(t, a)
 471 #define __BPF_MAP_2(m, v, t, a, ...) m(t, a), __BPF_MAP_1(m, v, __VA_ARGS__)
 472 #define __BPF_MAP_3(m, v, t, a, ...) m(t, a), __BPF_MAP_2(m, v, __VA_ARGS__)
 473 #define __BPF_MAP_4(m, v, t, a, ...) m(t, a), __BPF_MAP_3(m, v, __VA_ARGS__)
 474 #define __BPF_MAP_5(m, v, t, a, ...) m(t, a), __BPF_MAP_4(m, v, __VA_ARGS__)
 475
 476 #define __BPF_REG_0(...) __BPF_PAD(5)
 477 #define __BPF_REG_1(...) __BPF_MAP(1, __VA_ARGS__), __BPF_PAD(4)
 478 #define __BPF_REG_2(...) __BPF_MAP(2, __VA_ARGS__), __BPF_PAD(3)
 479 #define __BPF_REG_3(...) __BPF_MAP(3, __VA_ARGS__), __BPF_PAD(2)
 480 #define __BPF_REG_4(...) __BPF_MAP(4, __VA_ARGS__), __BPF_PAD(1)
 481 #define __BPF_REG_5(...) __BPF_MAP(5, __VA_ARGS__)
 482
 483 #define __BPF_MAP(n, ...) __BPF_MAP_##n(__VA_ARGS__)
 484 #define __BPF_REG(n, ...) __BPF_REG_##n(__VA_ARGS__)
 485
 486 #define __BPF_CAST(t, a)                                                       \
 487         (__force t)                                                            \
 488         (__force                                                               \
 489          typeof(__builtin_choose_expr(sizeof(t) == sizeof(unsigned long),      \
 490                                       (unsigned long)0, (t)0))) a
 491 #define __BPF_V void
 492 #define __BPF_N
 493
 494 #define __BPF_DECL_ARGS(t, a) t   a
 495 #define __BPF_DECL_REGS(t, a) u64 a
 496
 497 #define __BPF_PAD(n)                                                           \
 498         __BPF_MAP(n, __BPF_DECL_ARGS, __BPF_N, u64, __ur_1, u64, __ur_2,       \
 499                   u64, __ur_3, u64, __ur_4, u64, __ur_5)
 500
 501 #define BPF_CALL_x(x, name, ...)                                               \
 502         static __always_inline                                                 \
 503         u64 ____##name(__BPF_MAP(x, __BPF_DECL_ARGS, __BPF_V, __VA_ARGS__));   \
 504         typedef u64 (*btf_##name)(__BPF_MAP(x, __BPF_DECL_ARGS, __BPF_V, __VA_ARGS__)); \
 505         u64 name(__BPF_REG(x, __BPF_DECL_REGS, __BPF_N, __VA_ARGS__));         \
 506         u64 name(__BPF_REG(x, __BPF_DECL_REGS, __BPF_N, __VA_ARGS__))          \
 507         {                                                                      \
 508                 return ((btf_##name)____##name)(__BPF_MAP(x,__BPF_CAST,__BPF_N,__VA_ARGS__));\
 509         }                                                                      \
 510         static __always_inline                                                 \
 511         u64 ____##name(__BPF_MAP(x, __BPF_DECL_ARGS, __BPF_V, __VA_ARGS__))
 512
 513 #define BPF_CALL_0(name, ...)   BPF_CALL_x(0, name, __VA_ARGS__)
 514 #define BPF_CALL_1(name, ...)   BPF_CALL_x(1, name, __VA_ARGS__)
 515 #define BPF_CALL_2(name, ...)   BPF_CALL_x(2, name, __VA_ARGS__)
 516 #define BPF_CALL_3(name, ...)   BPF_CALL_x(3, name, __VA_ARGS__)
 517 #define BPF_CALL_4(name, ...)   BPF_CALL_x(4, name, __VA_ARGS__)
 518 #define BPF_CALL_5(name, ...)   BPF_CALL_x(5, name, __VA_ARGS__)
 519
 520 #define bpf_ctx_range(TYPE, MEMBER)                                             \
 521         offsetof(TYPE, MEMBER) ... offsetofend(TYPE, MEMBER) - 1
 522 #define bpf_ctx_range_till(TYPE, MEMBER1, MEMBER2)                              \
 523         offsetof(TYPE, MEMBER1) ... offsetofend(TYPE, MEMBER2) - 1
 524 #if BITS_PER_LONG == 64
 525 # define bpf_ctx_range_ptr(TYPE, MEMBER)                                        \
 526         offsetof(TYPE, MEMBER) ... offsetofend(TYPE, MEMBER) - 1
 527 #else
 528 # define bpf_ctx_range_ptr(TYPE, MEMBER)                                        \
 529         offsetof(TYPE, MEMBER) ... offsetof(TYPE, MEMBER) + 8 - 1
 530 #endif /* BITS_PER_LONG == 64 */
 531
 532 #define bpf_target_off(TYPE, MEMBER, SIZE, PTR_SIZE)                            \
 533         ({                                                                      \
 534                 BUILD_BUG_ON(sizeof_field(TYPE, MEMBER) != (SIZE));             \
 535                 *(PTR_SIZE) = (SIZE);                                           \
 536                 offsetof(TYPE, MEMBER);                                         \
 537         })
 538
 539 /* A struct sock_filter is architecture independent. */
 540 struct compat_sock_fprog {
 541         u16             len;
 542         compat_uptr_t   filter; /* struct sock_filter * */
 543 };
 544
 545 struct sock_fprog_kern {
 546         u16                     len;
 547         struct sock_filter      *filter;
 548 };
 549
 550 /* Some arches need doubleword alignment for their instructions and/or data */
 551 #define BPF_IMAGE_ALIGNMENT 8
 552
 553 struct bpf_binary_header {
 554         u32 pages;
 555         u8 image[] __aligned(BPF_IMAGE_ALIGNMENT);
 556 };
 557
 558 struct bpf_prog_stats {
 559         u64 cnt;
 560         u64 nsecs;
 561         u64 misses;
 562         struct u64_stats_sync syncp;
 563 } __aligned(2 * sizeof(u64));
 564
 565 struct bpf_prog {
 566         u16                     pages;          /* Number of allocated pages */
 567         u16                     jited:1,        /* Is our filter JIT'ed? */
 568                                 jit_requested:1,/* archs need to JIT the prog */
 569                                 gpl_compatible:1, /* Is filter GPL compatible? */
 570                                 cb_access:1,    /* Is control block accessed? */
 571                                 dst_needed:1,   /* Do we need dst entry? */
 572                                 blinded:1,      /* Was blinded */
 573                                 is_func:1,      /* program is a bpf function */
 574                                 kprobe_override:1, /* Do we override a kprobe? */
 575                                 has_callchain_buf:1, /* callchain buffer allocated? */
 576                                 enforce_expected_attach_type:1, /* Enforce expected_attach_type checking at attach time */
 577                                 call_get_stack:1, /* Do we call bpf_get_stack() or bpf_get_stackid() */
 578                                 call_get_func_ip:1; /* Do we call get_func_ip() */
 579         enum bpf_prog_type      type;           /* Type of BPF program */
 580         enum bpf_attach_type    expected_attach_type; /* For some prog types */
 581         u32                     len;            /* Number of filter blocks */
 582         u32                     jited_len;      /* Size of jited insns in bytes */
 583         u8                      tag[BPF_TAG_SIZE];
 584         struct bpf_prog_stats __percpu *stats;
 585         int __percpu            *active;
 586         unsigned int            (*bpf_func)(const void *ctx,
 587                                             const struct bpf_insn *insn);
 588         struct bpf_prog_aux     *aux;           /* Auxiliary fields */
 589         struct sock_fprog_kern  *orig_prog;     /* Original BPF program */
 590         /* Instructions for interpreter */
 591         struct sock_filter      insns[0];
 592         struct bpf_insn         insnsi[];
 593 };
 594
 595 struct sk_filter {
 596         refcount_t      refcnt;
 597         struct rcu_head rcu;
 598         struct bpf_prog *prog;
 599 };
 600
 601 DECLARE_STATIC_KEY_FALSE(bpf_stats_enabled_key);
 602
 603 typedef unsigned int (*bpf_dispatcher_fn)(const void *ctx,
 604                                           const struct bpf_insn *insnsi,
 605                                           unsigned int (*bpf_func)(const void *,
 606                                                                    const struct bpf_insn *));
 607
 608 static __always_inline u32 __bpf_prog_run(const struct bpf_prog *prog,
 609                                           const void *ctx,
 610                                           bpf_dispatcher_fn dfunc)
 611 {
 612         u32 ret;
 613
 614         cant_migrate();
 615         if (static_branch_unlikely(&bpf_stats_enabled_key)) {
 616                 struct bpf_prog_stats *stats;
 617                 u64 start = sched_clock();
 618
 619                 ret = dfunc(ctx, prog->insnsi, prog->bpf_func);
 620                 stats = this_cpu_ptr(prog->stats);
 621                 u64_stats_update_begin(&stats->syncp);
 622                 stats->cnt++;
 623                 stats->nsecs += sched_clock() - start;
 624                 u64_stats_update_end(&stats->syncp);
 625         } else {
 626                 ret = dfunc(ctx, prog->insnsi, prog->bpf_func);
 627         }
 628         return ret;
 629 }
 630
 631 static __always_inline u32 bpf_prog_run(const struct bpf_prog *prog, const void *ctx)
 632 {
 633         return __bpf_prog_run(prog, ctx, bpf_dispatcher_nop_func);
 634 }
 635
 636 /*
 637  * Use in preemptible and therefore migratable context to make sure that
 638  * the execution of the BPF program runs on one CPU.
 639  *
 640  * This uses migrate_disable/enable() explicitly to document that the
 641  * invocation of a BPF program does not require reentrancy protection
 642  * against a BPF program which is invoked from a preempting task.
 643  *
 644  * For non RT enabled kernels migrate_disable/enable() maps to
 645  * preempt_disable/enable(), i.e. it disables also preemption.
 646  */
 647 static inline u32 bpf_prog_run_pin_on_cpu(const struct bpf_prog *prog,
 648                                           const void *ctx)
 649 {
 650         u32 ret;
 651
 652         migrate_disable();
 653         ret = bpf_prog_run(prog, ctx);
 654         migrate_enable();
 655         return ret;
 656 }
 657
 658 #define BPF_SKB_CB_LEN QDISC_CB_PRIV_LEN
 659
 660 struct bpf_skb_data_end {
 661         struct qdisc_skb_cb qdisc_cb;
 662         void *data_meta;
 663         void *data_end;
 664 };
 665
 666 struct bpf_nh_params {
 667         u32 nh_family;
 668         union {
 669                 u32 ipv4_nh;
 670                 struct in6_addr ipv6_nh;
 671         };
 672 };
 673
 674 struct bpf_redirect_info {
 675         u32 flags;
 676         u32 tgt_index;
 677         void *tgt_value;
 678         struct bpf_map *map;
 679         u32 map_id;
 680         enum bpf_map_type map_type;
 681         u32 kern_flags;
 682         struct bpf_nh_params nh;
 683 };
 684
 685 DECLARE_PER_CPU(struct bpf_redirect_info, bpf_redirect_info);
 686
 687 /* flags for bpf_redirect_info kern_flags */
 688 #define BPF_RI_F_RF_NO_DIRECT   BIT(0)  /* no napi_direct on return_frame */
 689
 690 /* Compute the linear packet data range [data, data_end) which
 691  * will be accessed by various program types (cls_bpf, act_bpf,
 692  * lwt, ...). Subsystems allowing direct data access must (!)
 693  * ensure that cb[] area can be written to when BPF program is
 694  * invoked (otherwise cb[] save/restore is necessary).
 695  */
 696 static inline void bpf_compute_data_pointers(struct sk_buff *skb)
 697 {
 698         struct bpf_skb_data_end *cb = (struct bpf_skb_data_end *)skb->cb;
 699
 700         BUILD_BUG_ON(sizeof(*cb) > sizeof_field(struct sk_buff, cb));
 701         cb->data_meta = skb->data - skb_metadata_len(skb);
 702         cb->data_end  = skb->data + skb_headlen(skb);
 703 }
 704
 705 /* Similar to bpf_compute_data_pointers(), except that save orginal
 706  * data in cb->data and cb->meta_data for restore.
 707  */
 708 static inline void bpf_compute_and_save_data_end(
 709         struct sk_buff *skb, void **saved_data_end)
 710 {
 711         struct bpf_skb_data_end *cb = (struct bpf_skb_data_end *)skb->cb;
 712
 713         *saved_data_end = cb->data_end;
 714         cb->data_end  = skb->data + skb_headlen(skb);
 715 }
 716
 717 /* Restore data saved by bpf_compute_data_pointers(). */
 718 static inline void bpf_restore_data_end(
 719         struct sk_buff *skb, void *saved_data_end)
 720 {
 721         struct bpf_skb_data_end *cb = (struct bpf_skb_data_end *)skb->cb;
 722
 723         cb->data_end = saved_data_end;
 724 }
 725
 726 static inline u8 *bpf_skb_cb(const struct sk_buff *skb)
 727 {
 728         /* eBPF programs may read/write skb->cb[] area to transfer meta
 729          * data between tail calls. Since this also needs to work with
 730          * tc, that scratch memory is mapped to qdisc_skb_cb's data area.
 731          *
 732          * In some socket filter cases, the cb unfortunately needs to be
 733          * saved/restored so that protocol specific skb->cb[] data won't
 734          * be lost. In any case, due to unpriviledged eBPF programs
 735          * attached to sockets, we need to clear the bpf_skb_cb() area
 736          * to not leak previous contents to user space.
 737          */
 738         BUILD_BUG_ON(sizeof_field(struct __sk_buff, cb) != BPF_SKB_CB_LEN);
 739         BUILD_BUG_ON(sizeof_field(struct __sk_buff, cb) !=
 740                      sizeof_field(struct qdisc_skb_cb, data));
 741
 742         return qdisc_skb_cb(skb)->data;
 743 }
 744
 745 /* Must be invoked with migration disabled */
 746 static inline u32 __bpf_prog_run_save_cb(const struct bpf_prog *prog,
 747                                          const void *ctx)
 748 {
 749         const struct sk_buff *skb = ctx;
 750         u8 *cb_data = bpf_skb_cb(skb);
 751         u8 cb_saved[BPF_SKB_CB_LEN];
 752         u32 res;
 753
 754         if (unlikely(prog->cb_access)) {
 755                 memcpy(cb_saved, cb_data, sizeof(cb_saved));
 756                 memset(cb_data, 0, sizeof(cb_saved));
 757         }
 758
 759         res = bpf_prog_run(prog, skb);
 760
 761         if (unlikely(prog->cb_access))
 762                 memcpy(cb_data, cb_saved, sizeof(cb_saved));
 763
 764         return res;
 765 }
 766
 767 static inline u32 bpf_prog_run_save_cb(const struct bpf_prog *prog,
 768                                        struct sk_buff *skb)
 769 {
 770         u32 res;
 771
 772         migrate_disable();
 773         res = __bpf_prog_run_save_cb(prog, skb);
 774         migrate_enable();
 775         return res;
 776 }
 777
 778 static inline u32 bpf_prog_run_clear_cb(const struct bpf_prog *prog,
 779                                         struct sk_buff *skb)
 780 {
 781         u8 *cb_data = bpf_skb_cb(skb);
 782         u32 res;
 783
 784         if (unlikely(prog->cb_access))
 785                 memset(cb_data, 0, BPF_SKB_CB_LEN);
 786
 787         res = bpf_prog_run_pin_on_cpu(prog, skb);
 788         return res;
 789 }
 790
 791 DECLARE_BPF_DISPATCHER(xdp)
 792
 793 DECLARE_STATIC_KEY_FALSE(bpf_master_redirect_enabled_key);
 794
 795 u32 xdp_master_redirect(struct xdp_buff *xdp);
 796
 797 static __always_inline u32 bpf_prog_run_xdp(const struct bpf_prog *prog,
 798                                             struct xdp_buff *xdp)
 799 {
 800         /* Driver XDP hooks are invoked within a single NAPI poll cycle and thus
 801          * under local_bh_disable(), which provides the needed RCU protection
 802          * for accessing map entries.
 803          */
 804         u32 act = __bpf_prog_run(prog, xdp, BPF_DISPATCHER_FUNC(xdp));
 805
 806         if (static_branch_unlikely(&bpf_master_redirect_enabled_key)) {
 807                 if (act == XDP_TX && netif_is_bond_slave(xdp->rxq->dev))
 808                         act = xdp_master_redirect(xdp);
 809         }
 810
 811         return act;
 812 }
 813
 814 void bpf_prog_change_xdp(struct bpf_prog *prev_prog, struct bpf_prog *prog);
 815
 816 static inline u32 bpf_prog_insn_size(const struct bpf_prog *prog)
 817 {
 818         return prog->len * sizeof(struct bpf_insn);
 819 }
 820
 821 static inline u32 bpf_prog_tag_scratch_size(const struct bpf_prog *prog)
 822 {
 823         return round_up(bpf_prog_insn_size(prog) +
 824                         sizeof(__be64) + 1, SHA1_BLOCK_SIZE);
 825 }
 826
 827 static inline unsigned int bpf_prog_size(unsigned int proglen)
 828 {
 829         return max(sizeof(struct bpf_prog),
 830                    offsetof(struct bpf_prog, insns[proglen]));
 831 }
 832
 833 static inline bool bpf_prog_was_classic(const struct bpf_prog *prog)
 834 {
 835         /* When classic BPF programs have been loaded and the arch
 836          * does not have a classic BPF JIT (anymore), they have been
 837          * converted via bpf_migrate_filter() to eBPF and thus always
 838          * have an unspec program type.
 839          */
 840         return prog->type == BPF_PROG_TYPE_UNSPEC;
 841 }
 842
 843 static inline u32 bpf_ctx_off_adjust_machine(u32 size)
 844 {
 845         const u32 size_machine = sizeof(unsigned long);
 846
 847         if (size > size_machine && size % size_machine == 0)
 848                 size = size_machine;
 849
 850         return size;
 851 }
 852
 853 static inline bool
 854 bpf_ctx_narrow_access_ok(u32 off, u32 size, u32 size_default)
 855 {
 856         return size <= size_default && (size & (size - 1)) == 0;
 857 }
 858
 859 static inline u8
 860 bpf_ctx_narrow_access_offset(u32 off, u32 size, u32 size_default)
 861 {
 862         u8 access_off = off & (size_default - 1);
 863
 864 #ifdef __LITTLE_ENDIAN
 865         return access_off;
 866 #else
 867         return size_default - (access_off + size);
 868 #endif
 869 }
 870
 871 #define bpf_ctx_wide_access_ok(off, size, type, field)                  \
 872         (size == sizeof(__u64) &&                                       \
 873         off >= offsetof(type, field) &&                                 \
 874         off + sizeof(__u64) <= offsetofend(type, field) &&              \
 875         off % sizeof(__u64) == 0)
 876
 877 #define bpf_classic_proglen(fprog) (fprog->len * sizeof(fprog->filter[0]))
 878
 879 static inline void bpf_prog_lock_ro(struct bpf_prog *fp)
 880 {
 881 #ifndef CONFIG_BPF_JIT_ALWAYS_ON
 882         if (!fp->jited) {
 883                 set_vm_flush_reset_perms(fp);
 884                 set_memory_ro((unsigned long)fp, fp->pages);
 885         }
 886 #endif
 887 }
 888
 889 static inline void bpf_jit_binary_lock_ro(struct bpf_binary_header *hdr)
 890 {
 891         set_vm_flush_reset_perms(hdr);
 892         set_memory_ro((unsigned long)hdr, hdr->pages);
 893         set_memory_x((unsigned long)hdr, hdr->pages);
 894 }
 895
 896 static inline struct bpf_binary_header *
 897 bpf_jit_binary_hdr(const struct bpf_prog *fp)
 898 {
 899         unsigned long real_start = (unsigned long)fp->bpf_func;
 900         unsigned long addr = real_start & PAGE_MASK;
 901
 902         return (void *)addr;
 903 }
 904
 905 int sk_filter_trim_cap(struct sock *sk, struct sk_buff *skb, unsigned int cap);
 906 static inline int sk_filter(struct sock *sk, struct sk_buff *skb)
 907 {
 908         return sk_filter_trim_cap(sk, skb, 1);
 909 }
 910
 911 struct bpf_prog *bpf_prog_select_runtime(struct bpf_prog *fp, int *err);
 912 void bpf_prog_free(struct bpf_prog *fp);
 913
 914 bool bpf_opcode_in_insntable(u8 code);
 915
 916 void bpf_prog_free_linfo(struct bpf_prog *prog);
 917 void bpf_prog_fill_jited_linfo(struct bpf_prog *prog,
 918                                const u32 *insn_to_jit_off);
 919 int bpf_prog_alloc_jited_linfo(struct bpf_prog *prog);
 920 void bpf_prog_jit_attempt_done(struct bpf_prog *prog);
 921
 922 struct bpf_prog *bpf_prog_alloc(unsigned int size, gfp_t gfp_extra_flags);
 923 struct bpf_prog *bpf_prog_alloc_no_stats(unsigned int size, gfp_t gfp_extra_flags);
 924 struct bpf_prog *bpf_prog_realloc(struct bpf_prog *fp_old, unsigned int size,
 925                                   gfp_t gfp_extra_flags);
 926 void __bpf_prog_free(struct bpf_prog *fp);
 927
 928 static inline void bpf_prog_unlock_free(struct bpf_prog *fp)
 929 {
 930         __bpf_prog_free(fp);
 931 }
 932
 933 typedef int (*bpf_aux_classic_check_t)(struct sock_filter *filter,
 934                                        unsigned int flen);
 935
 936 int bpf_prog_create(struct bpf_prog **pfp, struct sock_fprog_kern *fprog);
 937 int bpf_prog_create_from_user(struct bpf_prog **pfp, struct sock_fprog *fprog,
 938                               bpf_aux_classic_check_t trans, bool save_orig);
 939 void bpf_prog_destroy(struct bpf_prog *fp);
 940
 941 int sk_attach_filter(struct sock_fprog *fprog, struct sock *sk);
 942 int sk_attach_bpf(u32 ufd, struct sock *sk);
 943 int sk_reuseport_attach_filter(struct sock_fprog *fprog, struct sock *sk);
 944 int sk_reuseport_attach_bpf(u32 ufd, struct sock *sk);
 945 void sk_reuseport_prog_free(struct bpf_prog *prog);
 946 int sk_detach_filter(struct sock *sk);
 947 int sk_get_filter(struct sock *sk, struct sock_filter __user *filter,
 948                   unsigned int len);
 949
 950 bool sk_filter_charge(struct sock *sk, struct sk_filter *fp);
 951 void sk_filter_uncharge(struct sock *sk, struct sk_filter *fp);
 952
 953 u64 __bpf_call_base(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5);
 954 #define __bpf_call_base_args \
 955         ((u64 (*)(u64, u64, u64, u64, u64, const struct bpf_insn *)) \
 956          (void *)__bpf_call_base)
 957
 958 struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog);
 959 void bpf_jit_compile(struct bpf_prog *prog);
 960 bool bpf_jit_needs_zext(void);
 961 bool bpf_jit_supports_kfunc_call(void);
 962 bool bpf_helper_changes_pkt_data(void *func);
 963
 964 static inline bool bpf_dump_raw_ok(const struct cred *cred)
 965 {
 966         /* Reconstruction of call-sites is dependent on kallsyms,
 967          * thus make dump the same restriction.
 968          */
 969         return kallsyms_show_value(cred);
 970 }
 971
 972 struct bpf_prog *bpf_patch_insn_single(struct bpf_prog *prog, u32 off,
 973                                        const struct bpf_insn *patch, u32 len);
 974 int bpf_remove_insns(struct bpf_prog *prog, u32 off, u32 cnt);
 975
 976 void bpf_clear_redirect_map(struct bpf_map *map);
 977
 978 static inline bool xdp_return_frame_no_direct(void)
 979 {
 980         struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
 981
 982         return ri->kern_flags & BPF_RI_F_RF_NO_DIRECT;
 983 }
 984
 985 static inline void xdp_set_return_frame_no_direct(void)
 986 {
 987         struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
 988
 989         ri->kern_flags |= BPF_RI_F_RF_NO_DIRECT;
 990 }
 991
 992 static inline void xdp_clear_return_frame_no_direct(void)
 993 {
 994         struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
 995
 996         ri->kern_flags &= ~BPF_RI_F_RF_NO_DIRECT;
 997 }
 998
 999 static inline int xdp_ok_fwd_dev(const struct net_device *fwd,
1000                                  unsigned int pktlen)
1001 {
1002         unsigned int len;
1003
1004         if (unlikely(!(fwd->flags & IFF_UP)))
1005                 return -ENETDOWN;
1006
1007         len = fwd->mtu + fwd->hard_header_len + VLAN_HLEN;
1008         if (pktlen > len)
1009                 return -EMSGSIZE;
1010
1011         return 0;
1012 }
1013
1014 /* The pair of xdp_do_redirect and xdp_do_flush MUST be called in the
1015  * same cpu context. Further for best results no more than a single map
1016  * for the do_redirect/do_flush pair should be used. This limitation is
1017  * because we only track one map and force a flush when the map changes.
1018  * This does not appear to be a real limitation for existing software.
1019  */
1020 int xdp_do_generic_redirect(struct net_device *dev, struct sk_buff *skb,
1021                             struct xdp_buff *xdp, struct bpf_prog *prog);
1022 int xdp_do_redirect(struct net_device *dev,
1023                     struct xdp_buff *xdp,
1024                     struct bpf_prog *prog);
1025 void xdp_do_flush(void);
1026
1027 /* The xdp_do_flush_map() helper has been renamed to drop the _map suffix, as
1028  * it is no longer only flushing maps. Keep this define for compatibility
1029  * until all drivers are updated - do not use xdp_do_flush_map() in new code!
1030  */
1031 #define xdp_do_flush_map xdp_do_flush
1032
1033 void bpf_warn_invalid_xdp_action(u32 act);
1034
1035 #ifdef CONFIG_INET
1036 struct sock *bpf_run_sk_reuseport(struct sock_reuseport *reuse, struct sock *sk,
1037                                   struct bpf_prog *prog, struct sk_buff *skb,
1038                                   struct sock *migrating_sk,
1039                                   u32 hash);
1040 #else
1041 static inline struct sock *
1042 bpf_run_sk_reuseport(struct sock_reuseport *reuse, struct sock *sk,
1043                      struct bpf_prog *prog, struct sk_buff *skb,
1044                      struct sock *migrating_sk,
1045                      u32 hash)
1046 {
1047         return NULL;
1048 }
1049 #endif
1050
1051 #ifdef CONFIG_BPF_JIT
1052 extern int bpf_jit_enable;
1053 extern int bpf_jit_harden;
1054 extern int bpf_jit_kallsyms;
1055 extern long bpf_jit_limit;
1056
1057 typedef void (*bpf_jit_fill_hole_t)(void *area, unsigned int size);
1058
1059 struct bpf_binary_header *
1060 bpf_jit_binary_alloc(unsigned int proglen, u8 **image_ptr,
1061                      unsigned int alignment,
1062                      bpf_jit_fill_hole_t bpf_fill_ill_insns);
1063 void bpf_jit_binary_free(struct bpf_binary_header *hdr);
1064 u64 bpf_jit_alloc_exec_limit(void);
1065 void *bpf_jit_alloc_exec(unsigned long size);
1066 void bpf_jit_free_exec(void *addr);
1067 void bpf_jit_free(struct bpf_prog *fp);
1068
1069 int bpf_jit_add_poke_descriptor(struct bpf_prog *prog,
1070                                 struct bpf_jit_poke_descriptor *poke);
1071
1072 int bpf_jit_get_func_addr(const struct bpf_prog *prog,
1073                           const struct bpf_insn *insn, bool extra_pass,
1074                           u64 *func_addr, bool *func_addr_fixed);
1075
1076 struct bpf_prog *bpf_jit_blind_constants(struct bpf_prog *fp);
1077 void bpf_jit_prog_release_other(struct bpf_prog *fp, struct bpf_prog *fp_other);
1078
1079 static inline void bpf_jit_dump(unsigned int flen, unsigned int proglen,
1080                                 u32 pass, void *image)
1081 {
1082         pr_err("flen=%u proglen=%u pass=%u image=%pK from=%s pid=%d\n", flen,
1083                proglen, pass, image, current->comm, task_pid_nr(current));
1084
1085         if (image)
1086                 print_hex_dump(KERN_ERR, "JIT code: ", DUMP_PREFIX_OFFSET,
1087                                16, 1, image, proglen, false);
1088 }
1089
1090 static inline bool bpf_jit_is_ebpf(void)
1091 {
1092 # ifdef CONFIG_HAVE_EBPF_JIT
1093         return true;
1094 # else
1095         return false;
1096 # endif
1097 }
1098
1099 static inline bool ebpf_jit_enabled(void)
1100 {
1101         return bpf_jit_enable && bpf_jit_is_ebpf();
1102 }
1103
1104 static inline bool bpf_prog_ebpf_jited(const struct bpf_prog *fp)
1105 {
1106         return fp->jited && bpf_jit_is_ebpf();
1107 }
1108
1109 static inline bool bpf_jit_blinding_enabled(struct bpf_prog *prog)
1110 {
1111         /* These are the prerequisites, should someone ever have the
1112          * idea to call blinding outside of them, we make sure to
1113          * bail out.
1114          */
1115         if (!bpf_jit_is_ebpf())
1116                 return false;
1117         if (!prog->jit_requested)
1118                 return false;
1119         if (!bpf_jit_harden)
1120                 return false;
1121         if (bpf_jit_harden == 1 && capable(CAP_SYS_ADMIN))
1122                 return false;
1123
1124         return true;
1125 }
1126
1127 static inline bool bpf_jit_kallsyms_enabled(void)
1128 {
1129         /* There are a couple of corner cases where kallsyms should
1130          * not be enabled f.e. on hardening.
1131          */
1132         if (bpf_jit_harden)
1133                 return false;
1134         if (!bpf_jit_kallsyms)
1135                 return false;
1136         if (bpf_jit_kallsyms == 1)
1137                 return true;
1138
1139         return false;
1140 }
1141
1142 const char *__bpf_address_lookup(unsigned long addr, unsigned long *size,
1143                                  unsigned long *off, char *sym);
1144 bool is_bpf_text_address(unsigned long addr);
1145 int bpf_get_kallsym(unsigned int symnum, unsigned long *value, char *type,
1146                     char *sym);
1147
1148 static inline const char *
1149 bpf_address_lookup(unsigned long addr, unsigned long *size,
1150                    unsigned long *off, char **modname, char *sym)
1151 {
1152         const char *ret = __bpf_address_lookup(addr, size, off, sym);
1153
1154         if (ret && modname)
1155                 *modname = NULL;
1156         return ret;
1157 }
1158
1159 void bpf_prog_kallsyms_add(struct bpf_prog *fp);
1160 void bpf_prog_kallsyms_del(struct bpf_prog *fp);
1161
1162 #else /* CONFIG_BPF_JIT */
1163
1164 static inline bool ebpf_jit_enabled(void)
1165 {
1166         return false;
1167 }
1168
1169 static inline bool bpf_jit_blinding_enabled(struct bpf_prog *prog)
1170 {
1171         return false;
1172 }
1173
1174 static inline bool bpf_prog_ebpf_jited(const struct bpf_prog *fp)
1175 {
1176         return false;
1177 }
1178
1179 static inline int
1180 bpf_jit_add_poke_descriptor(struct bpf_prog *prog,
1181                             struct bpf_jit_poke_descriptor *poke)
1182 {
1183         return -ENOTSUPP;
1184 }
1185
1186 static inline void bpf_jit_free(struct bpf_prog *fp)
1187 {
1188         bpf_prog_unlock_free(fp);
1189 }
1190
1191 static inline bool bpf_jit_kallsyms_enabled(void)
1192 {
1193         return false;
1194 }
1195
1196 static inline const char *
1197 __bpf_address_lookup(unsigned long addr, unsigned long *size,
1198                      unsigned long *off, char *sym)
1199 {
1200         return NULL;
1201 }
1202
1203 static inline bool is_bpf_text_address(unsigned long addr)
1204 {
1205         return false;
1206 }
1207
1208 static inline int bpf_get_kallsym(unsigned int symnum, unsigned long *value,
1209                                   char *type, char *sym)
1210 {
1211         return -ERANGE;
1212 }
1213
1214 static inline const char *
1215 bpf_address_lookup(unsigned long addr, unsigned long *size,
1216                    unsigned long *off, char **modname, char *sym)
1217 {
1218         return NULL;
1219 }
1220
1221 static inline void bpf_prog_kallsyms_add(struct bpf_prog *fp)
1222 {
1223 }
1224
1225 static inline void bpf_prog_kallsyms_del(struct bpf_prog *fp)
1226 {
1227 }
1228
1229 #endif /* CONFIG_BPF_JIT */
1230
1231 void bpf_prog_kallsyms_del_all(struct bpf_prog *fp);
1232
1233 #define BPF_ANC         BIT(15)
1234
1235 static inline bool bpf_needs_clear_a(const struct sock_filter *first)
1236 {
1237         switch (first->code) {
1238         case BPF_RET | BPF_K:
1239         case BPF_LD | BPF_W | BPF_LEN:
1240                 return false;
1241
1242         case BPF_LD | BPF_W | BPF_ABS:
1243         case BPF_LD | BPF_H | BPF_ABS:
1244         case BPF_LD | BPF_B | BPF_ABS:
1245                 if (first->k == SKF_AD_OFF + SKF_AD_ALU_XOR_X)
1246                         return true;
1247                 return false;
1248
1249         default:
1250                 return true;
1251         }
1252 }
1253
1254 static inline u16 bpf_anc_helper(const struct sock_filter *ftest)
1255 {
1256         BUG_ON(ftest->code & BPF_ANC);
1257
1258         switch (ftest->code) {
1259         case BPF_LD | BPF_W | BPF_ABS:
1260         case BPF_LD | BPF_H | BPF_ABS:
1261         case BPF_LD | BPF_B | BPF_ABS:
1262 #define BPF_ANCILLARY(CODE)     case SKF_AD_OFF + SKF_AD_##CODE:        \
1263                                 return BPF_ANC | SKF_AD_##CODE
1264                 switch (ftest->k) {
1265                 BPF_ANCILLARY(PROTOCOL);
1266                 BPF_ANCILLARY(PKTTYPE);
1267                 BPF_ANCILLARY(IFINDEX);
1268                 BPF_ANCILLARY(NLATTR);
1269                 BPF_ANCILLARY(NLATTR_NEST);
1270                 BPF_ANCILLARY(MARK);
1271                 BPF_ANCILLARY(QUEUE);
1272                 BPF_ANCILLARY(HATYPE);
1273                 BPF_ANCILLARY(RXHASH);
1274                 BPF_ANCILLARY(CPU);
1275                 BPF_ANCILLARY(ALU_XOR_X);
1276                 BPF_ANCILLARY(VLAN_TAG);
1277                 BPF_ANCILLARY(VLAN_TAG_PRESENT);
1278                 BPF_ANCILLARY(PAY_OFFSET);
1279                 BPF_ANCILLARY(RANDOM);
1280                 BPF_ANCILLARY(VLAN_TPID);
1281                 }
1282                 fallthrough;
1283         default:
1284                 return ftest->code;
1285         }
1286 }
1287
1288 void *bpf_internal_load_pointer_neg_helper(const struct sk_buff *skb,
1289                                            int k, unsigned int size);
1290
1291 static inline int bpf_tell_extensions(void)
1292 {
1293         return SKF_AD_MAX;
1294 }
1295
1296 struct bpf_sock_addr_kern {
1297         struct sock *sk;
1298         struct sockaddr *uaddr;
1299         /* Temporary "register" to make indirect stores to nested structures
1300          * defined above. We need three registers to make such a store, but
1301          * only two (src and dst) are available at convert_ctx_access time
1302          */
1303         u64 tmp_reg;
1304         void *t_ctx;    /* Attach type specific context. */
1305 };
1306
1307 struct bpf_sock_ops_kern {
1308         struct  sock *sk;
1309         union {
1310                 u32 args[4];
1311                 u32 reply;
1312                 u32 replylong[4];
1313         };
1314         struct sk_buff  *syn_skb;
1315         struct sk_buff  *skb;
1316         void    *skb_data_end;
1317         u8      op;
1318         u8      is_fullsock;
1319         u8      remaining_opt_len;
1320         u64     temp;                   /* temp and everything after is not
1321                                          * initialized to 0 before calling
1322                                          * the BPF program. New fields that
1323                                          * should be initialized to 0 should
1324                                          * be inserted before temp.
1325                                          * temp is scratch storage used by
1326                                          * sock_ops_convert_ctx_access
1327                                          * as temporary storage of a register.
1328                                          */
1329 };
1330
1331 struct bpf_sysctl_kern {
1332         struct ctl_table_header *head;
1333         struct ctl_table *table;
1334         void *cur_val;
1335         size_t cur_len;
1336         void *new_val;
1337         size_t new_len;
1338         int new_updated;
1339         int write;
1340         loff_t *ppos;
1341         /* Temporary "register" for indirect stores to ppos. */
1342         u64 tmp_reg;
1343 };
1344
1345 #define BPF_SOCKOPT_KERN_BUF_SIZE       32
1346 struct bpf_sockopt_buf {
1347         u8              data[BPF_SOCKOPT_KERN_BUF_SIZE];
1348 };
1349
1350 struct bpf_sockopt_kern {
1351         struct sock     *sk;
1352         u8              *optval;
1353         u8              *optval_end;
1354         s32             level;
1355         s32             optname;
1356         s32             optlen;
1357         s32             retval;
1358 };
1359
1360 int copy_bpf_fprog_from_user(struct sock_fprog *dst, sockptr_t src, int len);
1361
1362 struct bpf_sk_lookup_kern {
1363         u16             family;
1364         u16             protocol;
1365         __be16          sport;
1366         u16             dport;
1367         struct {
1368                 __be32 saddr;
1369                 __be32 daddr;
1370         } v4;
1371         struct {
1372                 const struct in6_addr *saddr;
1373                 const struct in6_addr *daddr;
1374         } v6;
1375         struct sock     *selected_sk;
1376         bool            no_reuseport;
1377 };
1378
1379 extern struct static_key_false bpf_sk_lookup_enabled;
1380
1381 /* Runners for BPF_SK_LOOKUP programs to invoke on socket lookup.
1382  *
1383  * Allowed return values for a BPF SK_LOOKUP program are SK_PASS and
1384  * SK_DROP. Their meaning is as follows:
1385  *
1386  *  SK_PASS && ctx.selected_sk != NULL: use selected_sk as lookup result
1387  *  SK_PASS && ctx.selected_sk == NULL: continue to htable-based socket lookup
1388  *  SK_DROP                           : terminate lookup with -ECONNREFUSED
1389  *
1390  * This macro aggregates return values and selected sockets from
1391  * multiple BPF programs according to following rules in order:
1392  *
1393  *  1. If any program returned SK_PASS and a non-NULL ctx.selected_sk,
1394  *     macro result is SK_PASS and last ctx.selected_sk is used.
1395  *  2. If any program returned SK_DROP return value,
1396  *     macro result is SK_DROP.
1397  *  3. Otherwise result is SK_PASS and ctx.selected_sk is NULL.
1398  *
1399  * Caller must ensure that the prog array is non-NULL, and that the
1400  * array as well as the programs it contains remain valid.
1401  */
1402 #define BPF_PROG_SK_LOOKUP_RUN_ARRAY(array, ctx, func)                  \
1403         ({                                                              \
1404                 struct bpf_sk_lookup_kern *_ctx = &(ctx);               \
1405                 struct bpf_prog_array_item *_item;                      \
1406                 struct sock *_selected_sk = NULL;                       \
1407                 bool _no_reuseport = false;                             \
1408                 struct bpf_prog *_prog;                                 \
1409                 bool _all_pass = true;                                  \
1410                 u32 _ret;                                               \
1411                                                                         \
1412                 migrate_disable();                                      \
1413                 _item = &(array)->items[0];                             \
1414                 while ((_prog = READ_ONCE(_item->prog))) {              \
1415                         /* restore most recent selection */             \
1416                         _ctx->selected_sk = _selected_sk;               \
1417                         _ctx->no_reuseport = _no_reuseport;             \
1418                                                                         \
1419                         _ret = func(_prog, _ctx);                       \
1420                         if (_ret == SK_PASS && _ctx->selected_sk) {     \
1421                                 /* remember last non-NULL socket */     \
1422                                 _selected_sk = _ctx->selected_sk;       \
1423                                 _no_reuseport = _ctx->no_reuseport;     \
1424                         } else if (_ret == SK_DROP && _all_pass) {      \
1425                                 _all_pass = false;                      \
1426                         }                                               \
1427                         _item++;                                        \
1428                 }                                                       \
1429                 _ctx->selected_sk = _selected_sk;                       \
1430                 _ctx->no_reuseport = _no_reuseport;                     \
1431                 migrate_enable();                                       \
1432                 _all_pass || _selected_sk ? SK_PASS : SK_DROP;          \
1433          })
1434
1435 static inline bool bpf_sk_lookup_run_v4(struct net *net, int protocol,
1436                                         const __be32 saddr, const __be16 sport,
1437                                         const __be32 daddr, const u16 dport,
1438                                         struct sock **psk)
1439 {
1440         struct bpf_prog_array *run_array;
1441         struct sock *selected_sk = NULL;
1442         bool no_reuseport = false;
1443
1444         rcu_read_lock();
1445         run_array = rcu_dereference(net->bpf.run_array[NETNS_BPF_SK_LOOKUP]);
1446         if (run_array) {
1447                 struct bpf_sk_lookup_kern ctx = {
1448                         .family         = AF_INET,
1449                         .protocol       = protocol,
1450                         .v4.saddr       = saddr,
1451                         .v4.daddr       = daddr,
1452                         .sport          = sport,
1453                         .dport          = dport,
1454                 };
1455                 u32 act;
1456
1457                 act = BPF_PROG_SK_LOOKUP_RUN_ARRAY(run_array, ctx, bpf_prog_run);
1458                 if (act == SK_PASS) {
1459                         selected_sk = ctx.selected_sk;
1460                         no_reuseport = ctx.no_reuseport;
1461                 } else {
1462                         selected_sk = ERR_PTR(-ECONNREFUSED);
1463                 }
1464         }
1465         rcu_read_unlock();
1466         *psk = selected_sk;
1467         return no_reuseport;
1468 }
1469
1470 #if IS_ENABLED(CONFIG_IPV6)
1471 static inline bool bpf_sk_lookup_run_v6(struct net *net, int protocol,
1472                                         const struct in6_addr *saddr,
1473                                         const __be16 sport,
1474                                         const struct in6_addr *daddr,
1475                                         const u16 dport,
1476                                         struct sock **psk)
1477 {
1478         struct bpf_prog_array *run_array;
1479         struct sock *selected_sk = NULL;
1480         bool no_reuseport = false;
1481
1482         rcu_read_lock();
1483         run_array = rcu_dereference(net->bpf.run_array[NETNS_BPF_SK_LOOKUP]);
1484         if (run_array) {
1485                 struct bpf_sk_lookup_kern ctx = {
1486                         .family         = AF_INET6,
1487                         .protocol       = protocol,
1488                         .v6.saddr       = saddr,
1489                         .v6.daddr       = daddr,
1490                         .sport          = sport,
1491                         .dport          = dport,
1492                 };
1493                 u32 act;
1494
1495                 act = BPF_PROG_SK_LOOKUP_RUN_ARRAY(run_array, ctx, bpf_prog_run);
1496                 if (act == SK_PASS) {
1497                         selected_sk = ctx.selected_sk;
1498                         no_reuseport = ctx.no_reuseport;
1499                 } else {
1500                         selected_sk = ERR_PTR(-ECONNREFUSED);
1501                 }
1502         }
1503         rcu_read_unlock();
1504         *psk = selected_sk;
1505         return no_reuseport;
1506 }
1507 #endif /* IS_ENABLED(CONFIG_IPV6) */
1508
1509 static __always_inline int __bpf_xdp_redirect_map(struct bpf_map *map, u32 ifindex,
1510                                                   u64 flags, const u64 flag_mask,
1511                                                   void *lookup_elem(struct bpf_map *map, u32 key))
1512 {
1513         struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
1514         const u64 action_mask = XDP_ABORTED | XDP_DROP | XDP_PASS | XDP_TX;
1515
1516         /* Lower bits of the flags are used as return code on lookup failure */
1517         if (unlikely(flags & ~(action_mask | flag_mask)))
1518                 return XDP_ABORTED;
1519
1520         ri->tgt_value = lookup_elem(map, ifindex);
1521         if (unlikely(!ri->tgt_value) && !(flags & BPF_F_BROADCAST)) {
1522                 /* If the lookup fails we want to clear out the state in the
1523                  * redirect_info struct completely, so that if an eBPF program
1524                  * performs multiple lookups, the last one always takes
1525                  * precedence.
1526                  */
1527                 ri->map_id = INT_MAX; /* Valid map id idr range: [1,INT_MAX[ */
1528                 ri->map_type = BPF_MAP_TYPE_UNSPEC;
1529                 return flags & action_mask;
1530         }
1531
1532         ri->tgt_index = ifindex;
1533         ri->map_id = map->id;
1534         ri->map_type = map->map_type;
1535
1536         if (flags & BPF_F_BROADCAST) {
1537                 WRITE_ONCE(ri->map, map);
1538                 ri->flags = flags;
1539         } else {
1540                 WRITE_ONCE(ri->map, NULL);
1541                 ri->flags = 0;
1542         }
1543
1544         return XDP_REDIRECT;
1545 }
1546
1547 #endif /* __LINUX_FILTER_H__ */