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 <linux/atomic.h> 9 #include <linux/bpf.h> 10 #include <linux/refcount.h> 11 #include <linux/compat.h> 12 #include <linux/skbuff.h> 13 #include <linux/linkage.h> 14 #include <linux/printk.h> 15 #include <linux/workqueue.h> 16 #include <linux/sched.h> 17 #include <linux/sched/clock.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 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 special ldsx instruction. Same as BPF_IND */ 73 #define BPF_PROBE_MEMSX 0x40 74 75 /* unused opcode to mark special load instruction. Same as BPF_MSH */ 76 #define BPF_PROBE_MEM32 0xa0 77 78 /* unused opcode to mark special atomic instruction */ 79 #define BPF_PROBE_ATOMIC 0xe0 80 81 /* unused opcode to mark call to interpreter with arguments */ 82 #define BPF_CALL_ARGS 0xe0 83 84 /* unused opcode to mark speculation barrier for mitigating 85 * Speculative Store Bypass 86 */ 87 #define BPF_NOSPEC 0xc0 88 89 /* As per nm, we expose JITed images as text (code) section for 90 * kallsyms. That way, tools like perf can find it to match 91 * addresses. 92 */ 93 #define BPF_SYM_ELF_TYPE 't' 94 95 /* BPF program can access up to 512 bytes of stack space. */ 96 #define MAX_BPF_STACK 512 97 98 /* Helper macros for filter block array initializers. */ 99 100 /* ALU ops on registers, bpf_add|sub|...: dst_reg += src_reg */ 101 102 #define BPF_ALU64_REG_OFF(OP, DST, SRC, OFF) \ 103 ((struct bpf_insn) { \ 104 .code = BPF_ALU64 | BPF_OP(OP) | BPF_X, \ 105 .dst_reg = DST, \ 106 .src_reg = SRC, \ 107 .off = OFF, \ 108 .imm = 0 }) 109 110 #define BPF_ALU64_REG(OP, DST, SRC) \ 111 BPF_ALU64_REG_OFF(OP, DST, SRC, 0) 112 113 #define BPF_ALU32_REG_OFF(OP, DST, SRC, OFF) \ 114 ((struct bpf_insn) { \ 115 .code = BPF_ALU | BPF_OP(OP) | BPF_X, \ 116 .dst_reg = DST, \ 117 .src_reg = SRC, \ 118 .off = OFF, \ 119 .imm = 0 }) 120 121 #define BPF_ALU32_REG(OP, DST, SRC) \ 122 BPF_ALU32_REG_OFF(OP, DST, SRC, 0) 123 124 /* ALU ops on immediates, bpf_add|sub|...: dst_reg += imm32 */ 125 126 #define BPF_ALU64_IMM_OFF(OP, DST, IMM, OFF) \ 127 ((struct bpf_insn) { \ 128 .code = BPF_ALU64 | BPF_OP(OP) | BPF_K, \ 129 .dst_reg = DST, \ 130 .src_reg = 0, \ 131 .off = OFF, \ 132 .imm = IMM }) 133 #define BPF_ALU64_IMM(OP, DST, IMM) \ 134 BPF_ALU64_IMM_OFF(OP, DST, IMM, 0) 135 136 #define BPF_ALU32_IMM_OFF(OP, DST, IMM, OFF) \ 137 ((struct bpf_insn) { \ 138 .code = BPF_ALU | BPF_OP(OP) | BPF_K, \ 139 .dst_reg = DST, \ 140 .src_reg = 0, \ 141 .off = OFF, \ 142 .imm = IMM }) 143 #define BPF_ALU32_IMM(OP, DST, IMM) \ 144 BPF_ALU32_IMM_OFF(OP, DST, IMM, 0) 145 146 /* Endianess conversion, cpu_to_{l,b}e(), {l,b}e_to_cpu() */ 147 148 #define BPF_ENDIAN(TYPE, DST, LEN) \ 149 ((struct bpf_insn) { \ 150 .code = BPF_ALU | BPF_END | BPF_SRC(TYPE), \ 151 .dst_reg = DST, \ 152 .src_reg = 0, \ 153 .off = 0, \ 154 .imm = LEN }) 155 156 /* Byte Swap, bswap16/32/64 */ 157 158 #define BPF_BSWAP(DST, LEN) \ 159 ((struct bpf_insn) { \ 160 .code = BPF_ALU64 | BPF_END | BPF_SRC(BPF_TO_LE), \ 161 .dst_reg = DST, \ 162 .src_reg = 0, \ 163 .off = 0, \ 164 .imm = LEN }) 165 166 /* Short form of mov, dst_reg = src_reg */ 167 168 #define BPF_MOV64_REG(DST, SRC) \ 169 ((struct bpf_insn) { \ 170 .code = BPF_ALU64 | BPF_MOV | BPF_X, \ 171 .dst_reg = DST, \ 172 .src_reg = SRC, \ 173 .off = 0, \ 174 .imm = 0 }) 175 176 #define BPF_MOV32_REG(DST, SRC) \ 177 ((struct bpf_insn) { \ 178 .code = BPF_ALU | BPF_MOV | BPF_X, \ 179 .dst_reg = DST, \ 180 .src_reg = SRC, \ 181 .off = 0, \ 182 .imm = 0 }) 183 184 /* Special (internal-only) form of mov, used to resolve per-CPU addrs: 185 * dst_reg = src_reg + <percpu_base_off> 186 * BPF_ADDR_PERCPU is used as a special insn->off value. 187 */ 188 #define BPF_ADDR_PERCPU (-1) 189 190 #define BPF_MOV64_PERCPU_REG(DST, SRC) \ 191 ((struct bpf_insn) { \ 192 .code = BPF_ALU64 | BPF_MOV | BPF_X, \ 193 .dst_reg = DST, \ 194 .src_reg = SRC, \ 195 .off = BPF_ADDR_PERCPU, \ 196 .imm = 0 }) 197 198 static inline bool insn_is_mov_percpu_addr(const struct bpf_insn *insn) 199 { 200 return insn->code == (BPF_ALU64 | BPF_MOV | BPF_X) && insn->off == BPF_ADDR_PERCPU; 201 } 202 203 /* Short form of mov, dst_reg = imm32 */ 204 205 #define BPF_MOV64_IMM(DST, IMM) \ 206 ((struct bpf_insn) { \ 207 .code = BPF_ALU64 | BPF_MOV | BPF_K, \ 208 .dst_reg = DST, \ 209 .src_reg = 0, \ 210 .off = 0, \ 211 .imm = IMM }) 212 213 #define BPF_MOV32_IMM(DST, IMM) \ 214 ((struct bpf_insn) { \ 215 .code = BPF_ALU | BPF_MOV | BPF_K, \ 216 .dst_reg = DST, \ 217 .src_reg = 0, \ 218 .off = 0, \ 219 .imm = IMM }) 220 221 /* Short form of movsx, dst_reg = (s8,s16,s32)src_reg */ 222 223 #define BPF_MOVSX64_REG(DST, SRC, OFF) \ 224 ((struct bpf_insn) { \ 225 .code = BPF_ALU64 | BPF_MOV | BPF_X, \ 226 .dst_reg = DST, \ 227 .src_reg = SRC, \ 228 .off = OFF, \ 229 .imm = 0 }) 230 231 #define BPF_MOVSX32_REG(DST, SRC, OFF) \ 232 ((struct bpf_insn) { \ 233 .code = BPF_ALU | BPF_MOV | BPF_X, \ 234 .dst_reg = DST, \ 235 .src_reg = SRC, \ 236 .off = OFF, \ 237 .imm = 0 }) 238 239 /* Special form of mov32, used for doing explicit zero extension on dst. */ 240 #define BPF_ZEXT_REG(DST) \ 241 ((struct bpf_insn) { \ 242 .code = BPF_ALU | BPF_MOV | BPF_X, \ 243 .dst_reg = DST, \ 244 .src_reg = DST, \ 245 .off = 0, \ 246 .imm = 1 }) 247 248 static inline bool insn_is_zext(const struct bpf_insn *insn) 249 { 250 return insn->code == (BPF_ALU | BPF_MOV | BPF_X) && insn->imm == 1; 251 } 252 253 /* addr_space_cast from as(0) to as(1) is for converting bpf arena pointers 254 * to pointers in user vma. 255 */ 256 static inline bool insn_is_cast_user(const struct bpf_insn *insn) 257 { 258 return insn->code == (BPF_ALU64 | BPF_MOV | BPF_X) && 259 insn->off == BPF_ADDR_SPACE_CAST && 260 insn->imm == 1U << 16; 261 } 262 263 /* BPF_LD_IMM64 macro encodes single 'load 64-bit immediate' insn */ 264 #define BPF_LD_IMM64(DST, IMM) \ 265 BPF_LD_IMM64_RAW(DST, 0, IMM) 266 267 #define BPF_LD_IMM64_RAW(DST, SRC, IMM) \ 268 ((struct bpf_insn) { \ 269 .code = BPF_LD | BPF_DW | BPF_IMM, \ 270 .dst_reg = DST, \ 271 .src_reg = SRC, \ 272 .off = 0, \ 273 .imm = (__u32) (IMM) }), \ 274 ((struct bpf_insn) { \ 275 .code = 0, /* zero is reserved opcode */ \ 276 .dst_reg = 0, \ 277 .src_reg = 0, \ 278 .off = 0, \ 279 .imm = ((__u64) (IMM)) >> 32 }) 280 281 /* pseudo BPF_LD_IMM64 insn used to refer to process-local map_fd */ 282 #define BPF_LD_MAP_FD(DST, MAP_FD) \ 283 BPF_LD_IMM64_RAW(DST, BPF_PSEUDO_MAP_FD, MAP_FD) 284 285 /* Short form of mov based on type, BPF_X: dst_reg = src_reg, BPF_K: dst_reg = imm32 */ 286 287 #define BPF_MOV64_RAW(TYPE, DST, SRC, IMM) \ 288 ((struct bpf_insn) { \ 289 .code = BPF_ALU64 | BPF_MOV | BPF_SRC(TYPE), \ 290 .dst_reg = DST, \ 291 .src_reg = SRC, \ 292 .off = 0, \ 293 .imm = IMM }) 294 295 #define BPF_MOV32_RAW(TYPE, DST, SRC, IMM) \ 296 ((struct bpf_insn) { \ 297 .code = BPF_ALU | BPF_MOV | BPF_SRC(TYPE), \ 298 .dst_reg = DST, \ 299 .src_reg = SRC, \ 300 .off = 0, \ 301 .imm = IMM }) 302 303 /* Direct packet access, R0 = *(uint *) (skb->data + imm32) */ 304 305 #define BPF_LD_ABS(SIZE, IMM) \ 306 ((struct bpf_insn) { \ 307 .code = BPF_LD | BPF_SIZE(SIZE) | BPF_ABS, \ 308 .dst_reg = 0, \ 309 .src_reg = 0, \ 310 .off = 0, \ 311 .imm = IMM }) 312 313 /* Indirect packet access, R0 = *(uint *) (skb->data + src_reg + imm32) */ 314 315 #define BPF_LD_IND(SIZE, SRC, IMM) \ 316 ((struct bpf_insn) { \ 317 .code = BPF_LD | BPF_SIZE(SIZE) | BPF_IND, \ 318 .dst_reg = 0, \ 319 .src_reg = SRC, \ 320 .off = 0, \ 321 .imm = IMM }) 322 323 /* Memory load, dst_reg = *(uint *) (src_reg + off16) */ 324 325 #define BPF_LDX_MEM(SIZE, DST, SRC, OFF) \ 326 ((struct bpf_insn) { \ 327 .code = BPF_LDX | BPF_SIZE(SIZE) | BPF_MEM, \ 328 .dst_reg = DST, \ 329 .src_reg = SRC, \ 330 .off = OFF, \ 331 .imm = 0 }) 332 333 /* Memory load, dst_reg = *(signed size *) (src_reg + off16) */ 334 335 #define BPF_LDX_MEMSX(SIZE, DST, SRC, OFF) \ 336 ((struct bpf_insn) { \ 337 .code = BPF_LDX | BPF_SIZE(SIZE) | BPF_MEMSX, \ 338 .dst_reg = DST, \ 339 .src_reg = SRC, \ 340 .off = OFF, \ 341 .imm = 0 }) 342 343 /* Memory store, *(uint *) (dst_reg + off16) = src_reg */ 344 345 #define BPF_STX_MEM(SIZE, DST, SRC, OFF) \ 346 ((struct bpf_insn) { \ 347 .code = BPF_STX | BPF_SIZE(SIZE) | BPF_MEM, \ 348 .dst_reg = DST, \ 349 .src_reg = SRC, \ 350 .off = OFF, \ 351 .imm = 0 }) 352 353 354 /* 355 * Atomic operations: 356 * 357 * BPF_ADD *(uint *) (dst_reg + off16) += src_reg 358 * BPF_AND *(uint *) (dst_reg + off16) &= src_reg 359 * BPF_OR *(uint *) (dst_reg + off16) |= src_reg 360 * BPF_XOR *(uint *) (dst_reg + off16) ^= src_reg 361 * BPF_ADD | BPF_FETCH src_reg = atomic_fetch_add(dst_reg + off16, src_reg); 362 * BPF_AND | BPF_FETCH src_reg = atomic_fetch_and(dst_reg + off16, src_reg); 363 * BPF_OR | BPF_FETCH src_reg = atomic_fetch_or(dst_reg + off16, src_reg); 364 * BPF_XOR | BPF_FETCH src_reg = atomic_fetch_xor(dst_reg + off16, src_reg); 365 * BPF_XCHG src_reg = atomic_xchg(dst_reg + off16, src_reg) 366 * BPF_CMPXCHG r0 = atomic_cmpxchg(dst_reg + off16, r0, src_reg) 367 */ 368 369 #define BPF_ATOMIC_OP(SIZE, OP, DST, SRC, OFF) \ 370 ((struct bpf_insn) { \ 371 .code = BPF_STX | BPF_SIZE(SIZE) | BPF_ATOMIC, \ 372 .dst_reg = DST, \ 373 .src_reg = SRC, \ 374 .off = OFF, \ 375 .imm = OP }) 376 377 /* Legacy alias */ 378 #define BPF_STX_XADD(SIZE, DST, SRC, OFF) BPF_ATOMIC_OP(SIZE, BPF_ADD, DST, SRC, OFF) 379 380 /* Memory store, *(uint *) (dst_reg + off16) = imm32 */ 381 382 #define BPF_ST_MEM(SIZE, DST, OFF, IMM) \ 383 ((struct bpf_insn) { \ 384 .code = BPF_ST | BPF_SIZE(SIZE) | BPF_MEM, \ 385 .dst_reg = DST, \ 386 .src_reg = 0, \ 387 .off = OFF, \ 388 .imm = IMM }) 389 390 /* Conditional jumps against registers, if (dst_reg 'op' src_reg) goto pc + off16 */ 391 392 #define BPF_JMP_REG(OP, DST, SRC, OFF) \ 393 ((struct bpf_insn) { \ 394 .code = BPF_JMP | BPF_OP(OP) | BPF_X, \ 395 .dst_reg = DST, \ 396 .src_reg = SRC, \ 397 .off = OFF, \ 398 .imm = 0 }) 399 400 /* Conditional jumps against immediates, if (dst_reg 'op' imm32) goto pc + off16 */ 401 402 #define BPF_JMP_IMM(OP, DST, IMM, OFF) \ 403 ((struct bpf_insn) { \ 404 .code = BPF_JMP | BPF_OP(OP) | BPF_K, \ 405 .dst_reg = DST, \ 406 .src_reg = 0, \ 407 .off = OFF, \ 408 .imm = IMM }) 409 410 /* Like BPF_JMP_REG, but with 32-bit wide operands for comparison. */ 411 412 #define BPF_JMP32_REG(OP, DST, SRC, OFF) \ 413 ((struct bpf_insn) { \ 414 .code = BPF_JMP32 | BPF_OP(OP) | BPF_X, \ 415 .dst_reg = DST, \ 416 .src_reg = SRC, \ 417 .off = OFF, \ 418 .imm = 0 }) 419 420 /* Like BPF_JMP_IMM, but with 32-bit wide operands for comparison. */ 421 422 #define BPF_JMP32_IMM(OP, DST, IMM, OFF) \ 423 ((struct bpf_insn) { \ 424 .code = BPF_JMP32 | BPF_OP(OP) | BPF_K, \ 425 .dst_reg = DST, \ 426 .src_reg = 0, \ 427 .off = OFF, \ 428 .imm = IMM }) 429 430 /* Unconditional jumps, goto pc + off16 */ 431 432 #define BPF_JMP_A(OFF) \ 433 ((struct bpf_insn) { \ 434 .code = BPF_JMP | BPF_JA, \ 435 .dst_reg = 0, \ 436 .src_reg = 0, \ 437 .off = OFF, \ 438 .imm = 0 }) 439 440 /* Relative call */ 441 442 #define BPF_CALL_REL(TGT) \ 443 ((struct bpf_insn) { \ 444 .code = BPF_JMP | BPF_CALL, \ 445 .dst_reg = 0, \ 446 .src_reg = BPF_PSEUDO_CALL, \ 447 .off = 0, \ 448 .imm = TGT }) 449 450 /* Convert function address to BPF immediate */ 451 452 #define BPF_CALL_IMM(x) ((void *)(x) - (void *)__bpf_call_base) 453 454 #define BPF_EMIT_CALL(FUNC) \ 455 ((struct bpf_insn) { \ 456 .code = BPF_JMP | BPF_CALL, \ 457 .dst_reg = 0, \ 458 .src_reg = 0, \ 459 .off = 0, \ 460 .imm = BPF_CALL_IMM(FUNC) }) 461 462 /* Raw code statement block */ 463 464 #define BPF_RAW_INSN(CODE, DST, SRC, OFF, IMM) \ 465 ((struct bpf_insn) { \ 466 .code = CODE, \ 467 .dst_reg = DST, \ 468 .src_reg = SRC, \ 469 .off = OFF, \ 470 .imm = IMM }) 471 472 /* Program exit */ 473 474 #define BPF_EXIT_INSN() \ 475 ((struct bpf_insn) { \ 476 .code = BPF_JMP | BPF_EXIT, \ 477 .dst_reg = 0, \ 478 .src_reg = 0, \ 479 .off = 0, \ 480 .imm = 0 }) 481 482 /* Speculation barrier */ 483 484 #define BPF_ST_NOSPEC() \ 485 ((struct bpf_insn) { \ 486 .code = BPF_ST | BPF_NOSPEC, \ 487 .dst_reg = 0, \ 488 .src_reg = 0, \ 489 .off = 0, \ 490 .imm = 0 }) 491 492 /* Internal classic blocks for direct assignment */ 493 494 #define __BPF_STMT(CODE, K) \ 495 ((struct sock_filter) BPF_STMT(CODE, K)) 496 497 #define __BPF_JUMP(CODE, K, JT, JF) \ 498 ((struct sock_filter) BPF_JUMP(CODE, K, JT, JF)) 499 500 #define bytes_to_bpf_size(bytes) \ 501 ({ \ 502 int bpf_size = -EINVAL; \ 503 \ 504 if (bytes == sizeof(u8)) \ 505 bpf_size = BPF_B; \ 506 else if (bytes == sizeof(u16)) \ 507 bpf_size = BPF_H; \ 508 else if (bytes == sizeof(u32)) \ 509 bpf_size = BPF_W; \ 510 else if (bytes == sizeof(u64)) \ 511 bpf_size = BPF_DW; \ 512 \ 513 bpf_size; \ 514 }) 515 516 #define bpf_size_to_bytes(bpf_size) \ 517 ({ \ 518 int bytes = -EINVAL; \ 519 \ 520 if (bpf_size == BPF_B) \ 521 bytes = sizeof(u8); \ 522 else if (bpf_size == BPF_H) \ 523 bytes = sizeof(u16); \ 524 else if (bpf_size == BPF_W) \ 525 bytes = sizeof(u32); \ 526 else if (bpf_size == BPF_DW) \ 527 bytes = sizeof(u64); \ 528 \ 529 bytes; \ 530 }) 531 532 #define BPF_SIZEOF(type) \ 533 ({ \ 534 const int __size = bytes_to_bpf_size(sizeof(type)); \ 535 BUILD_BUG_ON(__size < 0); \ 536 __size; \ 537 }) 538 539 #define BPF_FIELD_SIZEOF(type, field) \ 540 ({ \ 541 const int __size = bytes_to_bpf_size(sizeof_field(type, field)); \ 542 BUILD_BUG_ON(__size < 0); \ 543 __size; \ 544 }) 545 546 #define BPF_LDST_BYTES(insn) \ 547 ({ \ 548 const int __size = bpf_size_to_bytes(BPF_SIZE((insn)->code)); \ 549 WARN_ON(__size < 0); \ 550 __size; \ 551 }) 552 553 #define __BPF_MAP_0(m, v, ...) v 554 #define __BPF_MAP_1(m, v, t, a, ...) m(t, a) 555 #define __BPF_MAP_2(m, v, t, a, ...) m(t, a), __BPF_MAP_1(m, v, __VA_ARGS__) 556 #define __BPF_MAP_3(m, v, t, a, ...) m(t, a), __BPF_MAP_2(m, v, __VA_ARGS__) 557 #define __BPF_MAP_4(m, v, t, a, ...) m(t, a), __BPF_MAP_3(m, v, __VA_ARGS__) 558 #define __BPF_MAP_5(m, v, t, a, ...) m(t, a), __BPF_MAP_4(m, v, __VA_ARGS__) 559 560 #define __BPF_REG_0(...) __BPF_PAD(5) 561 #define __BPF_REG_1(...) __BPF_MAP(1, __VA_ARGS__), __BPF_PAD(4) 562 #define __BPF_REG_2(...) __BPF_MAP(2, __VA_ARGS__), __BPF_PAD(3) 563 #define __BPF_REG_3(...) __BPF_MAP(3, __VA_ARGS__), __BPF_PAD(2) 564 #define __BPF_REG_4(...) __BPF_MAP(4, __VA_ARGS__), __BPF_PAD(1) 565 #define __BPF_REG_5(...) __BPF_MAP(5, __VA_ARGS__) 566 567 #define __BPF_MAP(n, ...) __BPF_MAP_##n(__VA_ARGS__) 568 #define __BPF_REG(n, ...) __BPF_REG_##n(__VA_ARGS__) 569 570 #define __BPF_CAST(t, a) \ 571 (__force t) \ 572 (__force \ 573 typeof(__builtin_choose_expr(sizeof(t) == sizeof(unsigned long), \ 574 (unsigned long)0, (t)0))) a 575 #define __BPF_V void 576 #define __BPF_N 577 578 #define __BPF_DECL_ARGS(t, a) t a 579 #define __BPF_DECL_REGS(t, a) u64 a 580 581 #define __BPF_PAD(n) \ 582 __BPF_MAP(n, __BPF_DECL_ARGS, __BPF_N, u64, __ur_1, u64, __ur_2, \ 583 u64, __ur_3, u64, __ur_4, u64, __ur_5) 584 585 #define BPF_CALL_x(x, attr, name, ...) \ 586 static __always_inline \ 587 u64 ____##name(__BPF_MAP(x, __BPF_DECL_ARGS, __BPF_V, __VA_ARGS__)); \ 588 typedef u64 (*btf_##name)(__BPF_MAP(x, __BPF_DECL_ARGS, __BPF_V, __VA_ARGS__)); \ 589 attr u64 name(__BPF_REG(x, __BPF_DECL_REGS, __BPF_N, __VA_ARGS__)); \ 590 attr u64 name(__BPF_REG(x, __BPF_DECL_REGS, __BPF_N, __VA_ARGS__)) \ 591 { \ 592 return ((btf_##name)____##name)(__BPF_MAP(x,__BPF_CAST,__BPF_N,__VA_ARGS__));\ 593 } \ 594 static __always_inline \ 595 u64 ____##name(__BPF_MAP(x, __BPF_DECL_ARGS, __BPF_V, __VA_ARGS__)) 596 597 #define __NOATTR 598 #define BPF_CALL_0(name, ...) BPF_CALL_x(0, __NOATTR, name, __VA_ARGS__) 599 #define BPF_CALL_1(name, ...) BPF_CALL_x(1, __NOATTR, name, __VA_ARGS__) 600 #define BPF_CALL_2(name, ...) BPF_CALL_x(2, __NOATTR, name, __VA_ARGS__) 601 #define BPF_CALL_3(name, ...) BPF_CALL_x(3, __NOATTR, name, __VA_ARGS__) 602 #define BPF_CALL_4(name, ...) BPF_CALL_x(4, __NOATTR, name, __VA_ARGS__) 603 #define BPF_CALL_5(name, ...) BPF_CALL_x(5, __NOATTR, name, __VA_ARGS__) 604 605 #define NOTRACE_BPF_CALL_1(name, ...) BPF_CALL_x(1, notrace, name, __VA_ARGS__) 606 607 #define bpf_ctx_range(TYPE, MEMBER) \ 608 offsetof(TYPE, MEMBER) ... offsetofend(TYPE, MEMBER) - 1 609 #define bpf_ctx_range_till(TYPE, MEMBER1, MEMBER2) \ 610 offsetof(TYPE, MEMBER1) ... offsetofend(TYPE, MEMBER2) - 1 611 #if BITS_PER_LONG == 64 612 # define bpf_ctx_range_ptr(TYPE, MEMBER) \ 613 offsetof(TYPE, MEMBER) ... offsetofend(TYPE, MEMBER) - 1 614 #else 615 # define bpf_ctx_range_ptr(TYPE, MEMBER) \ 616 offsetof(TYPE, MEMBER) ... offsetof(TYPE, MEMBER) + 8 - 1 617 #endif /* BITS_PER_LONG == 64 */ 618 619 #define bpf_target_off(TYPE, MEMBER, SIZE, PTR_SIZE) \ 620 ({ \ 621 BUILD_BUG_ON(sizeof_field(TYPE, MEMBER) != (SIZE)); \ 622 *(PTR_SIZE) = (SIZE); \ 623 offsetof(TYPE, MEMBER); \ 624 }) 625 626 /* A struct sock_filter is architecture independent. */ 627 struct compat_sock_fprog { 628 u16 len; 629 compat_uptr_t filter; /* struct sock_filter * */ 630 }; 631 632 struct sock_fprog_kern { 633 u16 len; 634 struct sock_filter *filter; 635 }; 636 637 /* Some arches need doubleword alignment for their instructions and/or data */ 638 #define BPF_IMAGE_ALIGNMENT 8 639 640 struct bpf_binary_header { 641 u32 size; 642 u8 image[] __aligned(BPF_IMAGE_ALIGNMENT); 643 }; 644 645 struct bpf_prog_stats { 646 u64_stats_t cnt; 647 u64_stats_t nsecs; 648 u64_stats_t misses; 649 struct u64_stats_sync syncp; 650 } __aligned(2 * sizeof(u64)); 651 652 struct sk_filter { 653 refcount_t refcnt; 654 struct rcu_head rcu; 655 struct bpf_prog *prog; 656 }; 657 658 DECLARE_STATIC_KEY_FALSE(bpf_stats_enabled_key); 659 660 extern struct mutex nf_conn_btf_access_lock; 661 extern int (*nfct_btf_struct_access)(struct bpf_verifier_log *log, 662 const struct bpf_reg_state *reg, 663 int off, int size); 664 665 typedef unsigned int (*bpf_dispatcher_fn)(const void *ctx, 666 const struct bpf_insn *insnsi, 667 unsigned int (*bpf_func)(const void *, 668 const struct bpf_insn *)); 669 670 static __always_inline u32 __bpf_prog_run(const struct bpf_prog *prog, 671 const void *ctx, 672 bpf_dispatcher_fn dfunc) 673 { 674 u32 ret; 675 676 cant_migrate(); 677 if (static_branch_unlikely(&bpf_stats_enabled_key)) { 678 struct bpf_prog_stats *stats; 679 u64 duration, start = sched_clock(); 680 unsigned long flags; 681 682 ret = dfunc(ctx, prog->insnsi, prog->bpf_func); 683 684 duration = sched_clock() - start; 685 stats = this_cpu_ptr(prog->stats); 686 flags = u64_stats_update_begin_irqsave(&stats->syncp); 687 u64_stats_inc(&stats->cnt); 688 u64_stats_add(&stats->nsecs, duration); 689 u64_stats_update_end_irqrestore(&stats->syncp, flags); 690 } else { 691 ret = dfunc(ctx, prog->insnsi, prog->bpf_func); 692 } 693 return ret; 694 } 695 696 static __always_inline u32 bpf_prog_run(const struct bpf_prog *prog, const void *ctx) 697 { 698 return __bpf_prog_run(prog, ctx, bpf_dispatcher_nop_func); 699 } 700 701 /* 702 * Use in preemptible and therefore migratable context to make sure that 703 * the execution of the BPF program runs on one CPU. 704 * 705 * This uses migrate_disable/enable() explicitly to document that the 706 * invocation of a BPF program does not require reentrancy protection 707 * against a BPF program which is invoked from a preempting task. 708 */ 709 static inline u32 bpf_prog_run_pin_on_cpu(const struct bpf_prog *prog, 710 const void *ctx) 711 { 712 u32 ret; 713 714 migrate_disable(); 715 ret = bpf_prog_run(prog, ctx); 716 migrate_enable(); 717 return ret; 718 } 719 720 #define BPF_SKB_CB_LEN QDISC_CB_PRIV_LEN 721 722 struct bpf_skb_data_end { 723 struct qdisc_skb_cb qdisc_cb; 724 void *data_meta; 725 void *data_end; 726 }; 727 728 struct bpf_nh_params { 729 u32 nh_family; 730 union { 731 u32 ipv4_nh; 732 struct in6_addr ipv6_nh; 733 }; 734 }; 735 736 struct bpf_redirect_info { 737 u64 tgt_index; 738 void *tgt_value; 739 struct bpf_map *map; 740 u32 flags; 741 u32 kern_flags; 742 u32 map_id; 743 enum bpf_map_type map_type; 744 struct bpf_nh_params nh; 745 }; 746 747 DECLARE_PER_CPU(struct bpf_redirect_info, bpf_redirect_info); 748 749 /* flags for bpf_redirect_info kern_flags */ 750 #define BPF_RI_F_RF_NO_DIRECT BIT(0) /* no napi_direct on return_frame */ 751 752 /* Compute the linear packet data range [data, data_end) which 753 * will be accessed by various program types (cls_bpf, act_bpf, 754 * lwt, ...). Subsystems allowing direct data access must (!) 755 * ensure that cb[] area can be written to when BPF program is 756 * invoked (otherwise cb[] save/restore is necessary). 757 */ 758 static inline void bpf_compute_data_pointers(struct sk_buff *skb) 759 { 760 struct bpf_skb_data_end *cb = (struct bpf_skb_data_end *)skb->cb; 761 762 BUILD_BUG_ON(sizeof(*cb) > sizeof_field(struct sk_buff, cb)); 763 cb->data_meta = skb->data - skb_metadata_len(skb); 764 cb->data_end = skb->data + skb_headlen(skb); 765 } 766 767 /* Similar to bpf_compute_data_pointers(), except that save orginal 768 * data in cb->data and cb->meta_data for restore. 769 */ 770 static inline void bpf_compute_and_save_data_end( 771 struct sk_buff *skb, void **saved_data_end) 772 { 773 struct bpf_skb_data_end *cb = (struct bpf_skb_data_end *)skb->cb; 774 775 *saved_data_end = cb->data_end; 776 cb->data_end = skb->data + skb_headlen(skb); 777 } 778 779 /* Restore data saved by bpf_compute_and_save_data_end(). */ 780 static inline void bpf_restore_data_end( 781 struct sk_buff *skb, void *saved_data_end) 782 { 783 struct bpf_skb_data_end *cb = (struct bpf_skb_data_end *)skb->cb; 784 785 cb->data_end = saved_data_end; 786 } 787 788 static inline u8 *bpf_skb_cb(const struct sk_buff *skb) 789 { 790 /* eBPF programs may read/write skb->cb[] area to transfer meta 791 * data between tail calls. Since this also needs to work with 792 * tc, that scratch memory is mapped to qdisc_skb_cb's data area. 793 * 794 * In some socket filter cases, the cb unfortunately needs to be 795 * saved/restored so that protocol specific skb->cb[] data won't 796 * be lost. In any case, due to unpriviledged eBPF programs 797 * attached to sockets, we need to clear the bpf_skb_cb() area 798 * to not leak previous contents to user space. 799 */ 800 BUILD_BUG_ON(sizeof_field(struct __sk_buff, cb) != BPF_SKB_CB_LEN); 801 BUILD_BUG_ON(sizeof_field(struct __sk_buff, cb) != 802 sizeof_field(struct qdisc_skb_cb, data)); 803 804 return qdisc_skb_cb(skb)->data; 805 } 806 807 /* Must be invoked with migration disabled */ 808 static inline u32 __bpf_prog_run_save_cb(const struct bpf_prog *prog, 809 const void *ctx) 810 { 811 const struct sk_buff *skb = ctx; 812 u8 *cb_data = bpf_skb_cb(skb); 813 u8 cb_saved[BPF_SKB_CB_LEN]; 814 u32 res; 815 816 if (unlikely(prog->cb_access)) { 817 memcpy(cb_saved, cb_data, sizeof(cb_saved)); 818 memset(cb_data, 0, sizeof(cb_saved)); 819 } 820 821 res = bpf_prog_run(prog, skb); 822 823 if (unlikely(prog->cb_access)) 824 memcpy(cb_data, cb_saved, sizeof(cb_saved)); 825 826 return res; 827 } 828 829 static inline u32 bpf_prog_run_save_cb(const struct bpf_prog *prog, 830 struct sk_buff *skb) 831 { 832 u32 res; 833 834 migrate_disable(); 835 res = __bpf_prog_run_save_cb(prog, skb); 836 migrate_enable(); 837 return res; 838 } 839 840 static inline u32 bpf_prog_run_clear_cb(const struct bpf_prog *prog, 841 struct sk_buff *skb) 842 { 843 u8 *cb_data = bpf_skb_cb(skb); 844 u32 res; 845 846 if (unlikely(prog->cb_access)) 847 memset(cb_data, 0, BPF_SKB_CB_LEN); 848 849 res = bpf_prog_run_pin_on_cpu(prog, skb); 850 return res; 851 } 852 853 DECLARE_BPF_DISPATCHER(xdp) 854 855 DECLARE_STATIC_KEY_FALSE(bpf_master_redirect_enabled_key); 856 857 u32 xdp_master_redirect(struct xdp_buff *xdp); 858 859 void bpf_prog_change_xdp(struct bpf_prog *prev_prog, struct bpf_prog *prog); 860 861 static inline u32 bpf_prog_insn_size(const struct bpf_prog *prog) 862 { 863 return prog->len * sizeof(struct bpf_insn); 864 } 865 866 static inline u32 bpf_prog_tag_scratch_size(const struct bpf_prog *prog) 867 { 868 return round_up(bpf_prog_insn_size(prog) + 869 sizeof(__be64) + 1, SHA1_BLOCK_SIZE); 870 } 871 872 static inline unsigned int bpf_prog_size(unsigned int proglen) 873 { 874 return max(sizeof(struct bpf_prog), 875 offsetof(struct bpf_prog, insns[proglen])); 876 } 877 878 static inline bool bpf_prog_was_classic(const struct bpf_prog *prog) 879 { 880 /* When classic BPF programs have been loaded and the arch 881 * does not have a classic BPF JIT (anymore), they have been 882 * converted via bpf_migrate_filter() to eBPF and thus always 883 * have an unspec program type. 884 */ 885 return prog->type == BPF_PROG_TYPE_UNSPEC; 886 } 887 888 static inline u32 bpf_ctx_off_adjust_machine(u32 size) 889 { 890 const u32 size_machine = sizeof(unsigned long); 891 892 if (size > size_machine && size % size_machine == 0) 893 size = size_machine; 894 895 return size; 896 } 897 898 static inline bool 899 bpf_ctx_narrow_access_ok(u32 off, u32 size, u32 size_default) 900 { 901 return size <= size_default && (size & (size - 1)) == 0; 902 } 903 904 static inline u8 905 bpf_ctx_narrow_access_offset(u32 off, u32 size, u32 size_default) 906 { 907 u8 access_off = off & (size_default - 1); 908 909 #ifdef __LITTLE_ENDIAN 910 return access_off; 911 #else 912 return size_default - (access_off + size); 913 #endif 914 } 915 916 #define bpf_ctx_wide_access_ok(off, size, type, field) \ 917 (size == sizeof(__u64) && \ 918 off >= offsetof(type, field) && \ 919 off + sizeof(__u64) <= offsetofend(type, field) && \ 920 off % sizeof(__u64) == 0) 921 922 #define bpf_classic_proglen(fprog) (fprog->len * sizeof(fprog->filter[0])) 923 924 static inline int __must_check bpf_prog_lock_ro(struct bpf_prog *fp) 925 { 926 #ifndef CONFIG_BPF_JIT_ALWAYS_ON 927 if (!fp->jited) { 928 set_vm_flush_reset_perms(fp); 929 return set_memory_ro((unsigned long)fp, fp->pages); 930 } 931 #endif 932 return 0; 933 } 934 935 static inline int __must_check 936 bpf_jit_binary_lock_ro(struct bpf_binary_header *hdr) 937 { 938 set_vm_flush_reset_perms(hdr); 939 return set_memory_rox((unsigned long)hdr, hdr->size >> PAGE_SHIFT); 940 } 941 942 int sk_filter_trim_cap(struct sock *sk, struct sk_buff *skb, unsigned int cap); 943 static inline int sk_filter(struct sock *sk, struct sk_buff *skb) 944 { 945 return sk_filter_trim_cap(sk, skb, 1); 946 } 947 948 struct bpf_prog *bpf_prog_select_runtime(struct bpf_prog *fp, int *err); 949 void bpf_prog_free(struct bpf_prog *fp); 950 951 bool bpf_opcode_in_insntable(u8 code); 952 953 void bpf_prog_fill_jited_linfo(struct bpf_prog *prog, 954 const u32 *insn_to_jit_off); 955 int bpf_prog_alloc_jited_linfo(struct bpf_prog *prog); 956 void bpf_prog_jit_attempt_done(struct bpf_prog *prog); 957 958 struct bpf_prog *bpf_prog_alloc(unsigned int size, gfp_t gfp_extra_flags); 959 struct bpf_prog *bpf_prog_alloc_no_stats(unsigned int size, gfp_t gfp_extra_flags); 960 struct bpf_prog *bpf_prog_realloc(struct bpf_prog *fp_old, unsigned int size, 961 gfp_t gfp_extra_flags); 962 void __bpf_prog_free(struct bpf_prog *fp); 963 964 static inline void bpf_prog_unlock_free(struct bpf_prog *fp) 965 { 966 __bpf_prog_free(fp); 967 } 968 969 typedef int (*bpf_aux_classic_check_t)(struct sock_filter *filter, 970 unsigned int flen); 971 972 int bpf_prog_create(struct bpf_prog **pfp, struct sock_fprog_kern *fprog); 973 int bpf_prog_create_from_user(struct bpf_prog **pfp, struct sock_fprog *fprog, 974 bpf_aux_classic_check_t trans, bool save_orig); 975 void bpf_prog_destroy(struct bpf_prog *fp); 976 977 int sk_attach_filter(struct sock_fprog *fprog, struct sock *sk); 978 int sk_attach_bpf(u32 ufd, struct sock *sk); 979 int sk_reuseport_attach_filter(struct sock_fprog *fprog, struct sock *sk); 980 int sk_reuseport_attach_bpf(u32 ufd, struct sock *sk); 981 void sk_reuseport_prog_free(struct bpf_prog *prog); 982 int sk_detach_filter(struct sock *sk); 983 int sk_get_filter(struct sock *sk, sockptr_t optval, unsigned int len); 984 985 bool sk_filter_charge(struct sock *sk, struct sk_filter *fp); 986 void sk_filter_uncharge(struct sock *sk, struct sk_filter *fp); 987 988 u64 __bpf_call_base(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5); 989 #define __bpf_call_base_args \ 990 ((u64 (*)(u64, u64, u64, u64, u64, const struct bpf_insn *)) \ 991 (void *)__bpf_call_base) 992 993 struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog); 994 void bpf_jit_compile(struct bpf_prog *prog); 995 bool bpf_jit_needs_zext(void); 996 bool bpf_jit_inlines_helper_call(s32 imm); 997 bool bpf_jit_supports_subprog_tailcalls(void); 998 bool bpf_jit_supports_percpu_insn(void); 999 bool bpf_jit_supports_kfunc_call(void); 1000 bool bpf_jit_supports_far_kfunc_call(void); 1001 bool bpf_jit_supports_exceptions(void); 1002 bool bpf_jit_supports_ptr_xchg(void); 1003 bool bpf_jit_supports_arena(void); 1004 bool bpf_jit_supports_insn(struct bpf_insn *insn, bool in_arena); 1005 void arch_bpf_stack_walk(bool (*consume_fn)(void *cookie, u64 ip, u64 sp, u64 bp), void *cookie); 1006 bool bpf_helper_changes_pkt_data(void *func); 1007 1008 static inline bool bpf_dump_raw_ok(const struct cred *cred) 1009 { 1010 /* Reconstruction of call-sites is dependent on kallsyms, 1011 * thus make dump the same restriction. 1012 */ 1013 return kallsyms_show_value(cred); 1014 } 1015 1016 struct bpf_prog *bpf_patch_insn_single(struct bpf_prog *prog, u32 off, 1017 const struct bpf_insn *patch, u32 len); 1018 int bpf_remove_insns(struct bpf_prog *prog, u32 off, u32 cnt); 1019 1020 void bpf_clear_redirect_map(struct bpf_map *map); 1021 1022 static inline bool xdp_return_frame_no_direct(void) 1023 { 1024 struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info); 1025 1026 return ri->kern_flags & BPF_RI_F_RF_NO_DIRECT; 1027 } 1028 1029 static inline void xdp_set_return_frame_no_direct(void) 1030 { 1031 struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info); 1032 1033 ri->kern_flags |= BPF_RI_F_RF_NO_DIRECT; 1034 } 1035 1036 static inline void xdp_clear_return_frame_no_direct(void) 1037 { 1038 struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info); 1039 1040 ri->kern_flags &= ~BPF_RI_F_RF_NO_DIRECT; 1041 } 1042 1043 static inline int xdp_ok_fwd_dev(const struct net_device *fwd, 1044 unsigned int pktlen) 1045 { 1046 unsigned int len; 1047 1048 if (unlikely(!(fwd->flags & IFF_UP))) 1049 return -ENETDOWN; 1050 1051 len = fwd->mtu + fwd->hard_header_len + VLAN_HLEN; 1052 if (pktlen > len) 1053 return -EMSGSIZE; 1054 1055 return 0; 1056 } 1057 1058 /* The pair of xdp_do_redirect and xdp_do_flush MUST be called in the 1059 * same cpu context. Further for best results no more than a single map 1060 * for the do_redirect/do_flush pair should be used. This limitation is 1061 * because we only track one map and force a flush when the map changes. 1062 * This does not appear to be a real limitation for existing software. 1063 */ 1064 int xdp_do_generic_redirect(struct net_device *dev, struct sk_buff *skb, 1065 struct xdp_buff *xdp, struct bpf_prog *prog); 1066 int xdp_do_redirect(struct net_device *dev, 1067 struct xdp_buff *xdp, 1068 struct bpf_prog *prog); 1069 int xdp_do_redirect_frame(struct net_device *dev, 1070 struct xdp_buff *xdp, 1071 struct xdp_frame *xdpf, 1072 struct bpf_prog *prog); 1073 void xdp_do_flush(void); 1074 1075 void bpf_warn_invalid_xdp_action(struct net_device *dev, struct bpf_prog *prog, u32 act); 1076 1077 #ifdef CONFIG_INET 1078 struct sock *bpf_run_sk_reuseport(struct sock_reuseport *reuse, struct sock *sk, 1079 struct bpf_prog *prog, struct sk_buff *skb, 1080 struct sock *migrating_sk, 1081 u32 hash); 1082 #else 1083 static inline struct sock * 1084 bpf_run_sk_reuseport(struct sock_reuseport *reuse, struct sock *sk, 1085 struct bpf_prog *prog, struct sk_buff *skb, 1086 struct sock *migrating_sk, 1087 u32 hash) 1088 { 1089 return NULL; 1090 } 1091 #endif 1092 1093 #ifdef CONFIG_BPF_JIT 1094 extern int bpf_jit_enable; 1095 extern int bpf_jit_harden; 1096 extern int bpf_jit_kallsyms; 1097 extern long bpf_jit_limit; 1098 extern long bpf_jit_limit_max; 1099 1100 typedef void (*bpf_jit_fill_hole_t)(void *area, unsigned int size); 1101 1102 void bpf_jit_fill_hole_with_zero(void *area, unsigned int size); 1103 1104 struct bpf_binary_header * 1105 bpf_jit_binary_alloc(unsigned int proglen, u8 **image_ptr, 1106 unsigned int alignment, 1107 bpf_jit_fill_hole_t bpf_fill_ill_insns); 1108 void bpf_jit_binary_free(struct bpf_binary_header *hdr); 1109 u64 bpf_jit_alloc_exec_limit(void); 1110 void *bpf_jit_alloc_exec(unsigned long size); 1111 void bpf_jit_free_exec(void *addr); 1112 void bpf_jit_free(struct bpf_prog *fp); 1113 struct bpf_binary_header * 1114 bpf_jit_binary_pack_hdr(const struct bpf_prog *fp); 1115 1116 void *bpf_prog_pack_alloc(u32 size, bpf_jit_fill_hole_t bpf_fill_ill_insns); 1117 void bpf_prog_pack_free(void *ptr, u32 size); 1118 1119 static inline bool bpf_prog_kallsyms_verify_off(const struct bpf_prog *fp) 1120 { 1121 return list_empty(&fp->aux->ksym.lnode) || 1122 fp->aux->ksym.lnode.prev == LIST_POISON2; 1123 } 1124 1125 struct bpf_binary_header * 1126 bpf_jit_binary_pack_alloc(unsigned int proglen, u8 **ro_image, 1127 unsigned int alignment, 1128 struct bpf_binary_header **rw_hdr, 1129 u8 **rw_image, 1130 bpf_jit_fill_hole_t bpf_fill_ill_insns); 1131 int bpf_jit_binary_pack_finalize(struct bpf_prog *prog, 1132 struct bpf_binary_header *ro_header, 1133 struct bpf_binary_header *rw_header); 1134 void bpf_jit_binary_pack_free(struct bpf_binary_header *ro_header, 1135 struct bpf_binary_header *rw_header); 1136 1137 int bpf_jit_add_poke_descriptor(struct bpf_prog *prog, 1138 struct bpf_jit_poke_descriptor *poke); 1139 1140 int bpf_jit_get_func_addr(const struct bpf_prog *prog, 1141 const struct bpf_insn *insn, bool extra_pass, 1142 u64 *func_addr, bool *func_addr_fixed); 1143 1144 struct bpf_prog *bpf_jit_blind_constants(struct bpf_prog *fp); 1145 void bpf_jit_prog_release_other(struct bpf_prog *fp, struct bpf_prog *fp_other); 1146 1147 static inline void bpf_jit_dump(unsigned int flen, unsigned int proglen, 1148 u32 pass, void *image) 1149 { 1150 pr_err("flen=%u proglen=%u pass=%u image=%pK from=%s pid=%d\n", flen, 1151 proglen, pass, image, current->comm, task_pid_nr(current)); 1152 1153 if (image) 1154 print_hex_dump(KERN_ERR, "JIT code: ", DUMP_PREFIX_OFFSET, 1155 16, 1, image, proglen, false); 1156 } 1157 1158 static inline bool bpf_jit_is_ebpf(void) 1159 { 1160 # ifdef CONFIG_HAVE_EBPF_JIT 1161 return true; 1162 # else 1163 return false; 1164 # endif 1165 } 1166 1167 static inline bool ebpf_jit_enabled(void) 1168 { 1169 return bpf_jit_enable && bpf_jit_is_ebpf(); 1170 } 1171 1172 static inline bool bpf_prog_ebpf_jited(const struct bpf_prog *fp) 1173 { 1174 return fp->jited && bpf_jit_is_ebpf(); 1175 } 1176 1177 static inline bool bpf_jit_blinding_enabled(struct bpf_prog *prog) 1178 { 1179 /* These are the prerequisites, should someone ever have the 1180 * idea to call blinding outside of them, we make sure to 1181 * bail out. 1182 */ 1183 if (!bpf_jit_is_ebpf()) 1184 return false; 1185 if (!prog->jit_requested) 1186 return false; 1187 if (!bpf_jit_harden) 1188 return false; 1189 if (bpf_jit_harden == 1 && bpf_token_capable(prog->aux->token, CAP_BPF)) 1190 return false; 1191 1192 return true; 1193 } 1194 1195 static inline bool bpf_jit_kallsyms_enabled(void) 1196 { 1197 /* There are a couple of corner cases where kallsyms should 1198 * not be enabled f.e. on hardening. 1199 */ 1200 if (bpf_jit_harden) 1201 return false; 1202 if (!bpf_jit_kallsyms) 1203 return false; 1204 if (bpf_jit_kallsyms == 1) 1205 return true; 1206 1207 return false; 1208 } 1209 1210 const char *__bpf_address_lookup(unsigned long addr, unsigned long *size, 1211 unsigned long *off, char *sym); 1212 bool is_bpf_text_address(unsigned long addr); 1213 int bpf_get_kallsym(unsigned int symnum, unsigned long *value, char *type, 1214 char *sym); 1215 struct bpf_prog *bpf_prog_ksym_find(unsigned long addr); 1216 1217 static inline const char * 1218 bpf_address_lookup(unsigned long addr, unsigned long *size, 1219 unsigned long *off, char **modname, char *sym) 1220 { 1221 const char *ret = __bpf_address_lookup(addr, size, off, sym); 1222 1223 if (ret && modname) 1224 *modname = NULL; 1225 return ret; 1226 } 1227 1228 void bpf_prog_kallsyms_add(struct bpf_prog *fp); 1229 void bpf_prog_kallsyms_del(struct bpf_prog *fp); 1230 1231 #else /* CONFIG_BPF_JIT */ 1232 1233 static inline bool ebpf_jit_enabled(void) 1234 { 1235 return false; 1236 } 1237 1238 static inline bool bpf_jit_blinding_enabled(struct bpf_prog *prog) 1239 { 1240 return false; 1241 } 1242 1243 static inline bool bpf_prog_ebpf_jited(const struct bpf_prog *fp) 1244 { 1245 return false; 1246 } 1247 1248 static inline int 1249 bpf_jit_add_poke_descriptor(struct bpf_prog *prog, 1250 struct bpf_jit_poke_descriptor *poke) 1251 { 1252 return -ENOTSUPP; 1253 } 1254 1255 static inline void bpf_jit_free(struct bpf_prog *fp) 1256 { 1257 bpf_prog_unlock_free(fp); 1258 } 1259 1260 static inline bool bpf_jit_kallsyms_enabled(void) 1261 { 1262 return false; 1263 } 1264 1265 static inline const char * 1266 __bpf_address_lookup(unsigned long addr, unsigned long *size, 1267 unsigned long *off, char *sym) 1268 { 1269 return NULL; 1270 } 1271 1272 static inline bool is_bpf_text_address(unsigned long addr) 1273 { 1274 return false; 1275 } 1276 1277 static inline int bpf_get_kallsym(unsigned int symnum, unsigned long *value, 1278 char *type, char *sym) 1279 { 1280 return -ERANGE; 1281 } 1282 1283 static inline struct bpf_prog *bpf_prog_ksym_find(unsigned long addr) 1284 { 1285 return NULL; 1286 } 1287 1288 static inline const char * 1289 bpf_address_lookup(unsigned long addr, unsigned long *size, 1290 unsigned long *off, char **modname, char *sym) 1291 { 1292 return NULL; 1293 } 1294 1295 static inline void bpf_prog_kallsyms_add(struct bpf_prog *fp) 1296 { 1297 } 1298 1299 static inline void bpf_prog_kallsyms_del(struct bpf_prog *fp) 1300 { 1301 } 1302 1303 #endif /* CONFIG_BPF_JIT */ 1304 1305 void bpf_prog_kallsyms_del_all(struct bpf_prog *fp); 1306 1307 #define BPF_ANC BIT(15) 1308 1309 static inline bool bpf_needs_clear_a(const struct sock_filter *first) 1310 { 1311 switch (first->code) { 1312 case BPF_RET | BPF_K: 1313 case BPF_LD | BPF_W | BPF_LEN: 1314 return false; 1315 1316 case BPF_LD | BPF_W | BPF_ABS: 1317 case BPF_LD | BPF_H | BPF_ABS: 1318 case BPF_LD | BPF_B | BPF_ABS: 1319 if (first->k == SKF_AD_OFF + SKF_AD_ALU_XOR_X) 1320 return true; 1321 return false; 1322 1323 default: 1324 return true; 1325 } 1326 } 1327 1328 static inline u16 bpf_anc_helper(const struct sock_filter *ftest) 1329 { 1330 BUG_ON(ftest->code & BPF_ANC); 1331 1332 switch (ftest->code) { 1333 case BPF_LD | BPF_W | BPF_ABS: 1334 case BPF_LD | BPF_H | BPF_ABS: 1335 case BPF_LD | BPF_B | BPF_ABS: 1336 #define BPF_ANCILLARY(CODE) case SKF_AD_OFF + SKF_AD_##CODE: \ 1337 return BPF_ANC | SKF_AD_##CODE 1338 switch (ftest->k) { 1339 BPF_ANCILLARY(PROTOCOL); 1340 BPF_ANCILLARY(PKTTYPE); 1341 BPF_ANCILLARY(IFINDEX); 1342 BPF_ANCILLARY(NLATTR); 1343 BPF_ANCILLARY(NLATTR_NEST); 1344 BPF_ANCILLARY(MARK); 1345 BPF_ANCILLARY(QUEUE); 1346 BPF_ANCILLARY(HATYPE); 1347 BPF_ANCILLARY(RXHASH); 1348 BPF_ANCILLARY(CPU); 1349 BPF_ANCILLARY(ALU_XOR_X); 1350 BPF_ANCILLARY(VLAN_TAG); 1351 BPF_ANCILLARY(VLAN_TAG_PRESENT); 1352 BPF_ANCILLARY(PAY_OFFSET); 1353 BPF_ANCILLARY(RANDOM); 1354 BPF_ANCILLARY(VLAN_TPID); 1355 } 1356 fallthrough; 1357 default: 1358 return ftest->code; 1359 } 1360 } 1361 1362 void *bpf_internal_load_pointer_neg_helper(const struct sk_buff *skb, 1363 int k, unsigned int size); 1364 1365 static inline int bpf_tell_extensions(void) 1366 { 1367 return SKF_AD_MAX; 1368 } 1369 1370 struct bpf_sock_addr_kern { 1371 struct sock *sk; 1372 struct sockaddr *uaddr; 1373 /* Temporary "register" to make indirect stores to nested structures 1374 * defined above. We need three registers to make such a store, but 1375 * only two (src and dst) are available at convert_ctx_access time 1376 */ 1377 u64 tmp_reg; 1378 void *t_ctx; /* Attach type specific context. */ 1379 u32 uaddrlen; 1380 }; 1381 1382 struct bpf_sock_ops_kern { 1383 struct sock *sk; 1384 union { 1385 u32 args[4]; 1386 u32 reply; 1387 u32 replylong[4]; 1388 }; 1389 struct sk_buff *syn_skb; 1390 struct sk_buff *skb; 1391 void *skb_data_end; 1392 u8 op; 1393 u8 is_fullsock; 1394 u8 remaining_opt_len; 1395 u64 temp; /* temp and everything after is not 1396 * initialized to 0 before calling 1397 * the BPF program. New fields that 1398 * should be initialized to 0 should 1399 * be inserted before temp. 1400 * temp is scratch storage used by 1401 * sock_ops_convert_ctx_access 1402 * as temporary storage of a register. 1403 */ 1404 }; 1405 1406 struct bpf_sysctl_kern { 1407 struct ctl_table_header *head; 1408 struct ctl_table *table; 1409 void *cur_val; 1410 size_t cur_len; 1411 void *new_val; 1412 size_t new_len; 1413 int new_updated; 1414 int write; 1415 loff_t *ppos; 1416 /* Temporary "register" for indirect stores to ppos. */ 1417 u64 tmp_reg; 1418 }; 1419 1420 #define BPF_SOCKOPT_KERN_BUF_SIZE 32 1421 struct bpf_sockopt_buf { 1422 u8 data[BPF_SOCKOPT_KERN_BUF_SIZE]; 1423 }; 1424 1425 struct bpf_sockopt_kern { 1426 struct sock *sk; 1427 u8 *optval; 1428 u8 *optval_end; 1429 s32 level; 1430 s32 optname; 1431 s32 optlen; 1432 /* for retval in struct bpf_cg_run_ctx */ 1433 struct task_struct *current_task; 1434 /* Temporary "register" for indirect stores to ppos. */ 1435 u64 tmp_reg; 1436 }; 1437 1438 int copy_bpf_fprog_from_user(struct sock_fprog *dst, sockptr_t src, int len); 1439 1440 struct bpf_sk_lookup_kern { 1441 u16 family; 1442 u16 protocol; 1443 __be16 sport; 1444 u16 dport; 1445 struct { 1446 __be32 saddr; 1447 __be32 daddr; 1448 } v4; 1449 struct { 1450 const struct in6_addr *saddr; 1451 const struct in6_addr *daddr; 1452 } v6; 1453 struct sock *selected_sk; 1454 u32 ingress_ifindex; 1455 bool no_reuseport; 1456 }; 1457 1458 extern struct static_key_false bpf_sk_lookup_enabled; 1459 1460 /* Runners for BPF_SK_LOOKUP programs to invoke on socket lookup. 1461 * 1462 * Allowed return values for a BPF SK_LOOKUP program are SK_PASS and 1463 * SK_DROP. Their meaning is as follows: 1464 * 1465 * SK_PASS && ctx.selected_sk != NULL: use selected_sk as lookup result 1466 * SK_PASS && ctx.selected_sk == NULL: continue to htable-based socket lookup 1467 * SK_DROP : terminate lookup with -ECONNREFUSED 1468 * 1469 * This macro aggregates return values and selected sockets from 1470 * multiple BPF programs according to following rules in order: 1471 * 1472 * 1. If any program returned SK_PASS and a non-NULL ctx.selected_sk, 1473 * macro result is SK_PASS and last ctx.selected_sk is used. 1474 * 2. If any program returned SK_DROP return value, 1475 * macro result is SK_DROP. 1476 * 3. Otherwise result is SK_PASS and ctx.selected_sk is NULL. 1477 * 1478 * Caller must ensure that the prog array is non-NULL, and that the 1479 * array as well as the programs it contains remain valid. 1480 */ 1481 #define BPF_PROG_SK_LOOKUP_RUN_ARRAY(array, ctx, func) \ 1482 ({ \ 1483 struct bpf_sk_lookup_kern *_ctx = &(ctx); \ 1484 struct bpf_prog_array_item *_item; \ 1485 struct sock *_selected_sk = NULL; \ 1486 bool _no_reuseport = false; \ 1487 struct bpf_prog *_prog; \ 1488 bool _all_pass = true; \ 1489 u32 _ret; \ 1490 \ 1491 migrate_disable(); \ 1492 _item = &(array)->items[0]; \ 1493 while ((_prog = READ_ONCE(_item->prog))) { \ 1494 /* restore most recent selection */ \ 1495 _ctx->selected_sk = _selected_sk; \ 1496 _ctx->no_reuseport = _no_reuseport; \ 1497 \ 1498 _ret = func(_prog, _ctx); \ 1499 if (_ret == SK_PASS && _ctx->selected_sk) { \ 1500 /* remember last non-NULL socket */ \ 1501 _selected_sk = _ctx->selected_sk; \ 1502 _no_reuseport = _ctx->no_reuseport; \ 1503 } else if (_ret == SK_DROP && _all_pass) { \ 1504 _all_pass = false; \ 1505 } \ 1506 _item++; \ 1507 } \ 1508 _ctx->selected_sk = _selected_sk; \ 1509 _ctx->no_reuseport = _no_reuseport; \ 1510 migrate_enable(); \ 1511 _all_pass || _selected_sk ? SK_PASS : SK_DROP; \ 1512 }) 1513 1514 static inline bool bpf_sk_lookup_run_v4(struct net *net, int protocol, 1515 const __be32 saddr, const __be16 sport, 1516 const __be32 daddr, const u16 dport, 1517 const int ifindex, struct sock **psk) 1518 { 1519 struct bpf_prog_array *run_array; 1520 struct sock *selected_sk = NULL; 1521 bool no_reuseport = false; 1522 1523 rcu_read_lock(); 1524 run_array = rcu_dereference(net->bpf.run_array[NETNS_BPF_SK_LOOKUP]); 1525 if (run_array) { 1526 struct bpf_sk_lookup_kern ctx = { 1527 .family = AF_INET, 1528 .protocol = protocol, 1529 .v4.saddr = saddr, 1530 .v4.daddr = daddr, 1531 .sport = sport, 1532 .dport = dport, 1533 .ingress_ifindex = ifindex, 1534 }; 1535 u32 act; 1536 1537 act = BPF_PROG_SK_LOOKUP_RUN_ARRAY(run_array, ctx, bpf_prog_run); 1538 if (act == SK_PASS) { 1539 selected_sk = ctx.selected_sk; 1540 no_reuseport = ctx.no_reuseport; 1541 } else { 1542 selected_sk = ERR_PTR(-ECONNREFUSED); 1543 } 1544 } 1545 rcu_read_unlock(); 1546 *psk = selected_sk; 1547 return no_reuseport; 1548 } 1549 1550 #if IS_ENABLED(CONFIG_IPV6) 1551 static inline bool bpf_sk_lookup_run_v6(struct net *net, int protocol, 1552 const struct in6_addr *saddr, 1553 const __be16 sport, 1554 const struct in6_addr *daddr, 1555 const u16 dport, 1556 const int ifindex, struct sock **psk) 1557 { 1558 struct bpf_prog_array *run_array; 1559 struct sock *selected_sk = NULL; 1560 bool no_reuseport = false; 1561 1562 rcu_read_lock(); 1563 run_array = rcu_dereference(net->bpf.run_array[NETNS_BPF_SK_LOOKUP]); 1564 if (run_array) { 1565 struct bpf_sk_lookup_kern ctx = { 1566 .family = AF_INET6, 1567 .protocol = protocol, 1568 .v6.saddr = saddr, 1569 .v6.daddr = daddr, 1570 .sport = sport, 1571 .dport = dport, 1572 .ingress_ifindex = ifindex, 1573 }; 1574 u32 act; 1575 1576 act = BPF_PROG_SK_LOOKUP_RUN_ARRAY(run_array, ctx, bpf_prog_run); 1577 if (act == SK_PASS) { 1578 selected_sk = ctx.selected_sk; 1579 no_reuseport = ctx.no_reuseport; 1580 } else { 1581 selected_sk = ERR_PTR(-ECONNREFUSED); 1582 } 1583 } 1584 rcu_read_unlock(); 1585 *psk = selected_sk; 1586 return no_reuseport; 1587 } 1588 #endif /* IS_ENABLED(CONFIG_IPV6) */ 1589 1590 static __always_inline long __bpf_xdp_redirect_map(struct bpf_map *map, u64 index, 1591 u64 flags, const u64 flag_mask, 1592 void *lookup_elem(struct bpf_map *map, u32 key)) 1593 { 1594 struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info); 1595 const u64 action_mask = XDP_ABORTED | XDP_DROP | XDP_PASS | XDP_TX; 1596 1597 /* Lower bits of the flags are used as return code on lookup failure */ 1598 if (unlikely(flags & ~(action_mask | flag_mask))) 1599 return XDP_ABORTED; 1600 1601 ri->tgt_value = lookup_elem(map, index); 1602 if (unlikely(!ri->tgt_value) && !(flags & BPF_F_BROADCAST)) { 1603 /* If the lookup fails we want to clear out the state in the 1604 * redirect_info struct completely, so that if an eBPF program 1605 * performs multiple lookups, the last one always takes 1606 * precedence. 1607 */ 1608 ri->map_id = INT_MAX; /* Valid map id idr range: [1,INT_MAX[ */ 1609 ri->map_type = BPF_MAP_TYPE_UNSPEC; 1610 return flags & action_mask; 1611 } 1612 1613 ri->tgt_index = index; 1614 ri->map_id = map->id; 1615 ri->map_type = map->map_type; 1616 1617 if (flags & BPF_F_BROADCAST) { 1618 WRITE_ONCE(ri->map, map); 1619 ri->flags = flags; 1620 } else { 1621 WRITE_ONCE(ri->map, NULL); 1622 ri->flags = 0; 1623 } 1624 1625 return XDP_REDIRECT; 1626 } 1627 1628 #ifdef CONFIG_NET 1629 int __bpf_skb_load_bytes(const struct sk_buff *skb, u32 offset, void *to, u32 len); 1630 int __bpf_skb_store_bytes(struct sk_buff *skb, u32 offset, const void *from, 1631 u32 len, u64 flags); 1632 int __bpf_xdp_load_bytes(struct xdp_buff *xdp, u32 offset, void *buf, u32 len); 1633 int __bpf_xdp_store_bytes(struct xdp_buff *xdp, u32 offset, void *buf, u32 len); 1634 void *bpf_xdp_pointer(struct xdp_buff *xdp, u32 offset, u32 len); 1635 void bpf_xdp_copy_buf(struct xdp_buff *xdp, unsigned long off, 1636 void *buf, unsigned long len, bool flush); 1637 #else /* CONFIG_NET */ 1638 static inline int __bpf_skb_load_bytes(const struct sk_buff *skb, u32 offset, 1639 void *to, u32 len) 1640 { 1641 return -EOPNOTSUPP; 1642 } 1643 1644 static inline int __bpf_skb_store_bytes(struct sk_buff *skb, u32 offset, 1645 const void *from, u32 len, u64 flags) 1646 { 1647 return -EOPNOTSUPP; 1648 } 1649 1650 static inline int __bpf_xdp_load_bytes(struct xdp_buff *xdp, u32 offset, 1651 void *buf, u32 len) 1652 { 1653 return -EOPNOTSUPP; 1654 } 1655 1656 static inline int __bpf_xdp_store_bytes(struct xdp_buff *xdp, u32 offset, 1657 void *buf, u32 len) 1658 { 1659 return -EOPNOTSUPP; 1660 } 1661 1662 static inline void *bpf_xdp_pointer(struct xdp_buff *xdp, u32 offset, u32 len) 1663 { 1664 return NULL; 1665 } 1666 1667 static inline void bpf_xdp_copy_buf(struct xdp_buff *xdp, unsigned long off, void *buf, 1668 unsigned long len, bool flush) 1669 { 1670 } 1671 #endif /* CONFIG_NET */ 1672 1673 #endif /* __LINUX_FILTER_H__ */ 1674