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/capability.h> 18 #include <linux/set_memory.h> 19 #include <linux/kallsyms.h> 20 #include <linux/if_vlan.h> 21 #include <linux/vmalloc.h> 22 #include <linux/sockptr.h> 23 #include <crypto/sha1.h> 24 #include <linux/u64_stats_sync.h> 25 26 #include <net/sch_generic.h> 27 28 #include <asm/byteorder.h> 29 #include <uapi/linux/filter.h> 30 31 struct sk_buff; 32 struct sock; 33 struct seccomp_data; 34 struct bpf_prog_aux; 35 struct xdp_rxq_info; 36 struct xdp_buff; 37 struct sock_reuseport; 38 struct ctl_table; 39 struct ctl_table_header; 40 41 /* ArgX, context and stack frame pointer register positions. Note, 42 * Arg1, Arg2, Arg3, etc are used as argument mappings of function 43 * calls in BPF_CALL instruction. 44 */ 45 #define BPF_REG_ARG1 BPF_REG_1 46 #define BPF_REG_ARG2 BPF_REG_2 47 #define BPF_REG_ARG3 BPF_REG_3 48 #define BPF_REG_ARG4 BPF_REG_4 49 #define BPF_REG_ARG5 BPF_REG_5 50 #define BPF_REG_CTX BPF_REG_6 51 #define BPF_REG_FP BPF_REG_10 52 53 /* Additional register mappings for converted user programs. */ 54 #define BPF_REG_A BPF_REG_0 55 #define BPF_REG_X BPF_REG_7 56 #define BPF_REG_TMP BPF_REG_2 /* scratch reg */ 57 #define BPF_REG_D BPF_REG_8 /* data, callee-saved */ 58 #define BPF_REG_H BPF_REG_9 /* hlen, callee-saved */ 59 60 /* Kernel hidden auxiliary/helper register. */ 61 #define BPF_REG_AX MAX_BPF_REG 62 #define MAX_BPF_EXT_REG (MAX_BPF_REG + 1) 63 #define MAX_BPF_JIT_REG MAX_BPF_EXT_REG 64 65 /* unused opcode to mark special call to bpf_tail_call() helper */ 66 #define BPF_TAIL_CALL 0xf0 67 68 /* unused opcode to mark special load instruction. Same as BPF_ABS */ 69 #define BPF_PROBE_MEM 0x20 70 71 /* unused opcode to mark call to interpreter with arguments */ 72 #define BPF_CALL_ARGS 0xe0 73 74 /* unused opcode to mark speculation barrier for mitigating 75 * Speculative Store Bypass 76 */ 77 #define BPF_NOSPEC 0xc0 78 79 /* As per nm, we expose JITed images as text (code) section for 80 * kallsyms. That way, tools like perf can find it to match 81 * addresses. 82 */ 83 #define BPF_SYM_ELF_TYPE 't' 84 85 /* BPF program can access up to 512 bytes of stack space. */ 86 #define MAX_BPF_STACK 512 87 88 /* Helper macros for filter block array initializers. */ 89 90 /* ALU ops on registers, bpf_add|sub|...: dst_reg += src_reg */ 91 92 #define BPF_ALU64_REG(OP, DST, SRC) \ 93 ((struct bpf_insn) { \ 94 .code = BPF_ALU64 | BPF_OP(OP) | BPF_X, \ 95 .dst_reg = DST, \ 96 .src_reg = SRC, \ 97 .off = 0, \ 98 .imm = 0 }) 99 100 #define BPF_ALU32_REG(OP, DST, SRC) \ 101 ((struct bpf_insn) { \ 102 .code = BPF_ALU | BPF_OP(OP) | BPF_X, \ 103 .dst_reg = DST, \ 104 .src_reg = SRC, \ 105 .off = 0, \ 106 .imm = 0 }) 107 108 /* ALU ops on immediates, bpf_add|sub|...: dst_reg += imm32 */ 109 110 #define BPF_ALU64_IMM(OP, DST, IMM) \ 111 ((struct bpf_insn) { \ 112 .code = BPF_ALU64 | BPF_OP(OP) | BPF_K, \ 113 .dst_reg = DST, \ 114 .src_reg = 0, \ 115 .off = 0, \ 116 .imm = IMM }) 117 118 #define BPF_ALU32_IMM(OP, DST, IMM) \ 119 ((struct bpf_insn) { \ 120 .code = BPF_ALU | BPF_OP(OP) | BPF_K, \ 121 .dst_reg = DST, \ 122 .src_reg = 0, \ 123 .off = 0, \ 124 .imm = IMM }) 125 126 /* Endianess conversion, cpu_to_{l,b}e(), {l,b}e_to_cpu() */ 127 128 #define BPF_ENDIAN(TYPE, DST, LEN) \ 129 ((struct bpf_insn) { \ 130 .code = BPF_ALU | BPF_END | BPF_SRC(TYPE), \ 131 .dst_reg = DST, \ 132 .src_reg = 0, \ 133 .off = 0, \ 134 .imm = LEN }) 135 136 /* Short form of mov, dst_reg = src_reg */ 137 138 #define BPF_MOV64_REG(DST, SRC) \ 139 ((struct bpf_insn) { \ 140 .code = BPF_ALU64 | BPF_MOV | BPF_X, \ 141 .dst_reg = DST, \ 142 .src_reg = SRC, \ 143 .off = 0, \ 144 .imm = 0 }) 145 146 #define BPF_MOV32_REG(DST, SRC) \ 147 ((struct bpf_insn) { \ 148 .code = BPF_ALU | BPF_MOV | BPF_X, \ 149 .dst_reg = DST, \ 150 .src_reg = SRC, \ 151 .off = 0, \ 152 .imm = 0 }) 153 154 /* Short form of mov, dst_reg = imm32 */ 155 156 #define BPF_MOV64_IMM(DST, IMM) \ 157 ((struct bpf_insn) { \ 158 .code = BPF_ALU64 | BPF_MOV | BPF_K, \ 159 .dst_reg = DST, \ 160 .src_reg = 0, \ 161 .off = 0, \ 162 .imm = IMM }) 163 164 #define BPF_MOV32_IMM(DST, IMM) \ 165 ((struct bpf_insn) { \ 166 .code = BPF_ALU | BPF_MOV | BPF_K, \ 167 .dst_reg = DST, \ 168 .src_reg = 0, \ 169 .off = 0, \ 170 .imm = IMM }) 171 172 /* Special form of mov32, used for doing explicit zero extension on dst. */ 173 #define BPF_ZEXT_REG(DST) \ 174 ((struct bpf_insn) { \ 175 .code = BPF_ALU | BPF_MOV | BPF_X, \ 176 .dst_reg = DST, \ 177 .src_reg = DST, \ 178 .off = 0, \ 179 .imm = 1 }) 180 181 static inline bool insn_is_zext(const struct bpf_insn *insn) 182 { 183 return insn->code == (BPF_ALU | BPF_MOV | BPF_X) && insn->imm == 1; 184 } 185 186 /* BPF_LD_IMM64 macro encodes single 'load 64-bit immediate' insn */ 187 #define BPF_LD_IMM64(DST, IMM) \ 188 BPF_LD_IMM64_RAW(DST, 0, IMM) 189 190 #define BPF_LD_IMM64_RAW(DST, SRC, IMM) \ 191 ((struct bpf_insn) { \ 192 .code = BPF_LD | BPF_DW | BPF_IMM, \ 193 .dst_reg = DST, \ 194 .src_reg = SRC, \ 195 .off = 0, \ 196 .imm = (__u32) (IMM) }), \ 197 ((struct bpf_insn) { \ 198 .code = 0, /* zero is reserved opcode */ \ 199 .dst_reg = 0, \ 200 .src_reg = 0, \ 201 .off = 0, \ 202 .imm = ((__u64) (IMM)) >> 32 }) 203 204 /* pseudo BPF_LD_IMM64 insn used to refer to process-local map_fd */ 205 #define BPF_LD_MAP_FD(DST, MAP_FD) \ 206 BPF_LD_IMM64_RAW(DST, BPF_PSEUDO_MAP_FD, MAP_FD) 207 208 /* Short form of mov based on type, BPF_X: dst_reg = src_reg, BPF_K: dst_reg = imm32 */ 209 210 #define BPF_MOV64_RAW(TYPE, DST, SRC, IMM) \ 211 ((struct bpf_insn) { \ 212 .code = BPF_ALU64 | BPF_MOV | BPF_SRC(TYPE), \ 213 .dst_reg = DST, \ 214 .src_reg = SRC, \ 215 .off = 0, \ 216 .imm = IMM }) 217 218 #define BPF_MOV32_RAW(TYPE, DST, SRC, IMM) \ 219 ((struct bpf_insn) { \ 220 .code = BPF_ALU | BPF_MOV | BPF_SRC(TYPE), \ 221 .dst_reg = DST, \ 222 .src_reg = SRC, \ 223 .off = 0, \ 224 .imm = IMM }) 225 226 /* Direct packet access, R0 = *(uint *) (skb->data + imm32) */ 227 228 #define BPF_LD_ABS(SIZE, IMM) \ 229 ((struct bpf_insn) { \ 230 .code = BPF_LD | BPF_SIZE(SIZE) | BPF_ABS, \ 231 .dst_reg = 0, \ 232 .src_reg = 0, \ 233 .off = 0, \ 234 .imm = IMM }) 235 236 /* Indirect packet access, R0 = *(uint *) (skb->data + src_reg + imm32) */ 237 238 #define BPF_LD_IND(SIZE, SRC, IMM) \ 239 ((struct bpf_insn) { \ 240 .code = BPF_LD | BPF_SIZE(SIZE) | BPF_IND, \ 241 .dst_reg = 0, \ 242 .src_reg = SRC, \ 243 .off = 0, \ 244 .imm = IMM }) 245 246 /* Memory load, dst_reg = *(uint *) (src_reg + off16) */ 247 248 #define BPF_LDX_MEM(SIZE, DST, SRC, OFF) \ 249 ((struct bpf_insn) { \ 250 .code = BPF_LDX | BPF_SIZE(SIZE) | BPF_MEM, \ 251 .dst_reg = DST, \ 252 .src_reg = SRC, \ 253 .off = OFF, \ 254 .imm = 0 }) 255 256 /* Memory store, *(uint *) (dst_reg + off16) = src_reg */ 257 258 #define BPF_STX_MEM(SIZE, DST, SRC, OFF) \ 259 ((struct bpf_insn) { \ 260 .code = BPF_STX | BPF_SIZE(SIZE) | BPF_MEM, \ 261 .dst_reg = DST, \ 262 .src_reg = SRC, \ 263 .off = OFF, \ 264 .imm = 0 }) 265 266 267 /* 268 * Atomic operations: 269 * 270 * BPF_ADD *(uint *) (dst_reg + off16) += src_reg 271 * BPF_AND *(uint *) (dst_reg + off16) &= src_reg 272 * BPF_OR *(uint *) (dst_reg + off16) |= src_reg 273 * BPF_XOR *(uint *) (dst_reg + off16) ^= src_reg 274 * BPF_ADD | BPF_FETCH src_reg = atomic_fetch_add(dst_reg + off16, src_reg); 275 * BPF_AND | BPF_FETCH src_reg = atomic_fetch_and(dst_reg + off16, src_reg); 276 * BPF_OR | BPF_FETCH src_reg = atomic_fetch_or(dst_reg + off16, src_reg); 277 * BPF_XOR | BPF_FETCH src_reg = atomic_fetch_xor(dst_reg + off16, src_reg); 278 * BPF_XCHG src_reg = atomic_xchg(dst_reg + off16, src_reg) 279 * BPF_CMPXCHG r0 = atomic_cmpxchg(dst_reg + off16, r0, src_reg) 280 */ 281 282 #define BPF_ATOMIC_OP(SIZE, OP, DST, SRC, OFF) \ 283 ((struct bpf_insn) { \ 284 .code = BPF_STX | BPF_SIZE(SIZE) | BPF_ATOMIC, \ 285 .dst_reg = DST, \ 286 .src_reg = SRC, \ 287 .off = OFF, \ 288 .imm = OP }) 289 290 /* Legacy alias */ 291 #define BPF_STX_XADD(SIZE, DST, SRC, OFF) BPF_ATOMIC_OP(SIZE, BPF_ADD, DST, SRC, OFF) 292 293 /* Memory store, *(uint *) (dst_reg + off16) = imm32 */ 294 295 #define BPF_ST_MEM(SIZE, DST, OFF, IMM) \ 296 ((struct bpf_insn) { \ 297 .code = BPF_ST | BPF_SIZE(SIZE) | BPF_MEM, \ 298 .dst_reg = DST, \ 299 .src_reg = 0, \ 300 .off = OFF, \ 301 .imm = IMM }) 302 303 /* Conditional jumps against registers, if (dst_reg 'op' src_reg) goto pc + off16 */ 304 305 #define BPF_JMP_REG(OP, DST, SRC, OFF) \ 306 ((struct bpf_insn) { \ 307 .code = BPF_JMP | BPF_OP(OP) | BPF_X, \ 308 .dst_reg = DST, \ 309 .src_reg = SRC, \ 310 .off = OFF, \ 311 .imm = 0 }) 312 313 /* Conditional jumps against immediates, if (dst_reg 'op' imm32) goto pc + off16 */ 314 315 #define BPF_JMP_IMM(OP, DST, IMM, OFF) \ 316 ((struct bpf_insn) { \ 317 .code = BPF_JMP | BPF_OP(OP) | BPF_K, \ 318 .dst_reg = DST, \ 319 .src_reg = 0, \ 320 .off = OFF, \ 321 .imm = IMM }) 322 323 /* Like BPF_JMP_REG, but with 32-bit wide operands for comparison. */ 324 325 #define BPF_JMP32_REG(OP, DST, SRC, OFF) \ 326 ((struct bpf_insn) { \ 327 .code = BPF_JMP32 | BPF_OP(OP) | BPF_X, \ 328 .dst_reg = DST, \ 329 .src_reg = SRC, \ 330 .off = OFF, \ 331 .imm = 0 }) 332 333 /* Like BPF_JMP_IMM, but with 32-bit wide operands for comparison. */ 334 335 #define BPF_JMP32_IMM(OP, DST, IMM, OFF) \ 336 ((struct bpf_insn) { \ 337 .code = BPF_JMP32 | BPF_OP(OP) | BPF_K, \ 338 .dst_reg = DST, \ 339 .src_reg = 0, \ 340 .off = OFF, \ 341 .imm = IMM }) 342 343 /* Unconditional jumps, goto pc + off16 */ 344 345 #define BPF_JMP_A(OFF) \ 346 ((struct bpf_insn) { \ 347 .code = BPF_JMP | BPF_JA, \ 348 .dst_reg = 0, \ 349 .src_reg = 0, \ 350 .off = OFF, \ 351 .imm = 0 }) 352 353 /* Relative call */ 354 355 #define BPF_CALL_REL(TGT) \ 356 ((struct bpf_insn) { \ 357 .code = BPF_JMP | BPF_CALL, \ 358 .dst_reg = 0, \ 359 .src_reg = BPF_PSEUDO_CALL, \ 360 .off = 0, \ 361 .imm = TGT }) 362 363 /* Convert function address to BPF immediate */ 364 365 #define BPF_CALL_IMM(x) ((void *)(x) - (void *)__bpf_call_base) 366 367 #define BPF_EMIT_CALL(FUNC) \ 368 ((struct bpf_insn) { \ 369 .code = BPF_JMP | BPF_CALL, \ 370 .dst_reg = 0, \ 371 .src_reg = 0, \ 372 .off = 0, \ 373 .imm = BPF_CALL_IMM(FUNC) }) 374 375 /* Raw code statement block */ 376 377 #define BPF_RAW_INSN(CODE, DST, SRC, OFF, IMM) \ 378 ((struct bpf_insn) { \ 379 .code = CODE, \ 380 .dst_reg = DST, \ 381 .src_reg = SRC, \ 382 .off = OFF, \ 383 .imm = IMM }) 384 385 /* Program exit */ 386 387 #define BPF_EXIT_INSN() \ 388 ((struct bpf_insn) { \ 389 .code = BPF_JMP | BPF_EXIT, \ 390 .dst_reg = 0, \ 391 .src_reg = 0, \ 392 .off = 0, \ 393 .imm = 0 }) 394 395 /* Speculation barrier */ 396 397 #define BPF_ST_NOSPEC() \ 398 ((struct bpf_insn) { \ 399 .code = BPF_ST | BPF_NOSPEC, \ 400 .dst_reg = 0, \ 401 .src_reg = 0, \ 402 .off = 0, \ 403 .imm = 0 }) 404 405 /* Internal classic blocks for direct assignment */ 406 407 #define __BPF_STMT(CODE, K) \ 408 ((struct sock_filter) BPF_STMT(CODE, K)) 409 410 #define __BPF_JUMP(CODE, K, JT, JF) \ 411 ((struct sock_filter) BPF_JUMP(CODE, K, JT, JF)) 412 413 #define bytes_to_bpf_size(bytes) \ 414 ({ \ 415 int bpf_size = -EINVAL; \ 416 \ 417 if (bytes == sizeof(u8)) \ 418 bpf_size = BPF_B; \ 419 else if (bytes == sizeof(u16)) \ 420 bpf_size = BPF_H; \ 421 else if (bytes == sizeof(u32)) \ 422 bpf_size = BPF_W; \ 423 else if (bytes == sizeof(u64)) \ 424 bpf_size = BPF_DW; \ 425 \ 426 bpf_size; \ 427 }) 428 429 #define bpf_size_to_bytes(bpf_size) \ 430 ({ \ 431 int bytes = -EINVAL; \ 432 \ 433 if (bpf_size == BPF_B) \ 434 bytes = sizeof(u8); \ 435 else if (bpf_size == BPF_H) \ 436 bytes = sizeof(u16); \ 437 else if (bpf_size == BPF_W) \ 438 bytes = sizeof(u32); \ 439 else if (bpf_size == BPF_DW) \ 440 bytes = sizeof(u64); \ 441 \ 442 bytes; \ 443 }) 444 445 #define BPF_SIZEOF(type) \ 446 ({ \ 447 const int __size = bytes_to_bpf_size(sizeof(type)); \ 448 BUILD_BUG_ON(__size < 0); \ 449 __size; \ 450 }) 451 452 #define BPF_FIELD_SIZEOF(type, field) \ 453 ({ \ 454 const int __size = bytes_to_bpf_size(sizeof_field(type, field)); \ 455 BUILD_BUG_ON(__size < 0); \ 456 __size; \ 457 }) 458 459 #define BPF_LDST_BYTES(insn) \ 460 ({ \ 461 const int __size = bpf_size_to_bytes(BPF_SIZE((insn)->code)); \ 462 WARN_ON(__size < 0); \ 463 __size; \ 464 }) 465 466 #define __BPF_MAP_0(m, v, ...) v 467 #define __BPF_MAP_1(m, v, t, a, ...) m(t, a) 468 #define __BPF_MAP_2(m, v, t, a, ...) m(t, a), __BPF_MAP_1(m, v, __VA_ARGS__) 469 #define __BPF_MAP_3(m, v, t, a, ...) m(t, a), __BPF_MAP_2(m, v, __VA_ARGS__) 470 #define __BPF_MAP_4(m, v, t, a, ...) m(t, a), __BPF_MAP_3(m, v, __VA_ARGS__) 471 #define __BPF_MAP_5(m, v, t, a, ...) m(t, a), __BPF_MAP_4(m, v, __VA_ARGS__) 472 473 #define __BPF_REG_0(...) __BPF_PAD(5) 474 #define __BPF_REG_1(...) __BPF_MAP(1, __VA_ARGS__), __BPF_PAD(4) 475 #define __BPF_REG_2(...) __BPF_MAP(2, __VA_ARGS__), __BPF_PAD(3) 476 #define __BPF_REG_3(...) __BPF_MAP(3, __VA_ARGS__), __BPF_PAD(2) 477 #define __BPF_REG_4(...) __BPF_MAP(4, __VA_ARGS__), __BPF_PAD(1) 478 #define __BPF_REG_5(...) __BPF_MAP(5, __VA_ARGS__) 479 480 #define __BPF_MAP(n, ...) __BPF_MAP_##n(__VA_ARGS__) 481 #define __BPF_REG(n, ...) __BPF_REG_##n(__VA_ARGS__) 482 483 #define __BPF_CAST(t, a) \ 484 (__force t) \ 485 (__force \ 486 typeof(__builtin_choose_expr(sizeof(t) == sizeof(unsigned long), \ 487 (unsigned long)0, (t)0))) a 488 #define __BPF_V void 489 #define __BPF_N 490 491 #define __BPF_DECL_ARGS(t, a) t a 492 #define __BPF_DECL_REGS(t, a) u64 a 493 494 #define __BPF_PAD(n) \ 495 __BPF_MAP(n, __BPF_DECL_ARGS, __BPF_N, u64, __ur_1, u64, __ur_2, \ 496 u64, __ur_3, u64, __ur_4, u64, __ur_5) 497 498 #define BPF_CALL_x(x, name, ...) \ 499 static __always_inline \ 500 u64 ____##name(__BPF_MAP(x, __BPF_DECL_ARGS, __BPF_V, __VA_ARGS__)); \ 501 typedef u64 (*btf_##name)(__BPF_MAP(x, __BPF_DECL_ARGS, __BPF_V, __VA_ARGS__)); \ 502 u64 name(__BPF_REG(x, __BPF_DECL_REGS, __BPF_N, __VA_ARGS__)); \ 503 u64 name(__BPF_REG(x, __BPF_DECL_REGS, __BPF_N, __VA_ARGS__)) \ 504 { \ 505 return ((btf_##name)____##name)(__BPF_MAP(x,__BPF_CAST,__BPF_N,__VA_ARGS__));\ 506 } \ 507 static __always_inline \ 508 u64 ____##name(__BPF_MAP(x, __BPF_DECL_ARGS, __BPF_V, __VA_ARGS__)) 509 510 #define BPF_CALL_0(name, ...) BPF_CALL_x(0, name, __VA_ARGS__) 511 #define BPF_CALL_1(name, ...) BPF_CALL_x(1, name, __VA_ARGS__) 512 #define BPF_CALL_2(name, ...) BPF_CALL_x(2, name, __VA_ARGS__) 513 #define BPF_CALL_3(name, ...) BPF_CALL_x(3, name, __VA_ARGS__) 514 #define BPF_CALL_4(name, ...) BPF_CALL_x(4, name, __VA_ARGS__) 515 #define BPF_CALL_5(name, ...) BPF_CALL_x(5, name, __VA_ARGS__) 516 517 #define bpf_ctx_range(TYPE, MEMBER) \ 518 offsetof(TYPE, MEMBER) ... offsetofend(TYPE, MEMBER) - 1 519 #define bpf_ctx_range_till(TYPE, MEMBER1, MEMBER2) \ 520 offsetof(TYPE, MEMBER1) ... offsetofend(TYPE, MEMBER2) - 1 521 #if BITS_PER_LONG == 64 522 # define bpf_ctx_range_ptr(TYPE, MEMBER) \ 523 offsetof(TYPE, MEMBER) ... offsetofend(TYPE, MEMBER) - 1 524 #else 525 # define bpf_ctx_range_ptr(TYPE, MEMBER) \ 526 offsetof(TYPE, MEMBER) ... offsetof(TYPE, MEMBER) + 8 - 1 527 #endif /* BITS_PER_LONG == 64 */ 528 529 #define bpf_target_off(TYPE, MEMBER, SIZE, PTR_SIZE) \ 530 ({ \ 531 BUILD_BUG_ON(sizeof_field(TYPE, MEMBER) != (SIZE)); \ 532 *(PTR_SIZE) = (SIZE); \ 533 offsetof(TYPE, MEMBER); \ 534 }) 535 536 /* A struct sock_filter is architecture independent. */ 537 struct compat_sock_fprog { 538 u16 len; 539 compat_uptr_t filter; /* struct sock_filter * */ 540 }; 541 542 struct sock_fprog_kern { 543 u16 len; 544 struct sock_filter *filter; 545 }; 546 547 /* Some arches need doubleword alignment for their instructions and/or data */ 548 #define BPF_IMAGE_ALIGNMENT 8 549 550 struct bpf_binary_header { 551 u32 size; 552 u8 image[] __aligned(BPF_IMAGE_ALIGNMENT); 553 }; 554 555 struct bpf_prog_stats { 556 u64_stats_t cnt; 557 u64_stats_t nsecs; 558 u64_stats_t misses; 559 struct u64_stats_sync syncp; 560 } __aligned(2 * sizeof(u64)); 561 562 struct sk_filter { 563 refcount_t refcnt; 564 struct rcu_head rcu; 565 struct bpf_prog *prog; 566 }; 567 568 DECLARE_STATIC_KEY_FALSE(bpf_stats_enabled_key); 569 570 typedef unsigned int (*bpf_dispatcher_fn)(const void *ctx, 571 const struct bpf_insn *insnsi, 572 unsigned int (*bpf_func)(const void *, 573 const struct bpf_insn *)); 574 575 static __always_inline u32 __bpf_prog_run(const struct bpf_prog *prog, 576 const void *ctx, 577 bpf_dispatcher_fn dfunc) 578 { 579 u32 ret; 580 581 cant_migrate(); 582 if (static_branch_unlikely(&bpf_stats_enabled_key)) { 583 struct bpf_prog_stats *stats; 584 u64 start = sched_clock(); 585 unsigned long flags; 586 587 ret = dfunc(ctx, prog->insnsi, prog->bpf_func); 588 stats = this_cpu_ptr(prog->stats); 589 flags = u64_stats_update_begin_irqsave(&stats->syncp); 590 u64_stats_inc(&stats->cnt); 591 u64_stats_add(&stats->nsecs, sched_clock() - start); 592 u64_stats_update_end_irqrestore(&stats->syncp, flags); 593 } else { 594 ret = dfunc(ctx, prog->insnsi, prog->bpf_func); 595 } 596 return ret; 597 } 598 599 static __always_inline u32 bpf_prog_run(const struct bpf_prog *prog, const void *ctx) 600 { 601 return __bpf_prog_run(prog, ctx, bpf_dispatcher_nop_func); 602 } 603 604 /* 605 * Use in preemptible and therefore migratable context to make sure that 606 * the execution of the BPF program runs on one CPU. 607 * 608 * This uses migrate_disable/enable() explicitly to document that the 609 * invocation of a BPF program does not require reentrancy protection 610 * against a BPF program which is invoked from a preempting task. 611 */ 612 static inline u32 bpf_prog_run_pin_on_cpu(const struct bpf_prog *prog, 613 const void *ctx) 614 { 615 u32 ret; 616 617 migrate_disable(); 618 ret = bpf_prog_run(prog, ctx); 619 migrate_enable(); 620 return ret; 621 } 622 623 #define BPF_SKB_CB_LEN QDISC_CB_PRIV_LEN 624 625 struct bpf_skb_data_end { 626 struct qdisc_skb_cb qdisc_cb; 627 void *data_meta; 628 void *data_end; 629 }; 630 631 struct bpf_nh_params { 632 u32 nh_family; 633 union { 634 u32 ipv4_nh; 635 struct in6_addr ipv6_nh; 636 }; 637 }; 638 639 struct bpf_redirect_info { 640 u32 flags; 641 u32 tgt_index; 642 void *tgt_value; 643 struct bpf_map *map; 644 u32 map_id; 645 enum bpf_map_type map_type; 646 u32 kern_flags; 647 struct bpf_nh_params nh; 648 }; 649 650 DECLARE_PER_CPU(struct bpf_redirect_info, bpf_redirect_info); 651 652 /* flags for bpf_redirect_info kern_flags */ 653 #define BPF_RI_F_RF_NO_DIRECT BIT(0) /* no napi_direct on return_frame */ 654 655 /* Compute the linear packet data range [data, data_end) which 656 * will be accessed by various program types (cls_bpf, act_bpf, 657 * lwt, ...). Subsystems allowing direct data access must (!) 658 * ensure that cb[] area can be written to when BPF program is 659 * invoked (otherwise cb[] save/restore is necessary). 660 */ 661 static inline void bpf_compute_data_pointers(struct sk_buff *skb) 662 { 663 struct bpf_skb_data_end *cb = (struct bpf_skb_data_end *)skb->cb; 664 665 BUILD_BUG_ON(sizeof(*cb) > sizeof_field(struct sk_buff, cb)); 666 cb->data_meta = skb->data - skb_metadata_len(skb); 667 cb->data_end = skb->data + skb_headlen(skb); 668 } 669 670 /* Similar to bpf_compute_data_pointers(), except that save orginal 671 * data in cb->data and cb->meta_data for restore. 672 */ 673 static inline void bpf_compute_and_save_data_end( 674 struct sk_buff *skb, void **saved_data_end) 675 { 676 struct bpf_skb_data_end *cb = (struct bpf_skb_data_end *)skb->cb; 677 678 *saved_data_end = cb->data_end; 679 cb->data_end = skb->data + skb_headlen(skb); 680 } 681 682 /* Restore data saved by bpf_compute_data_pointers(). */ 683 static inline void bpf_restore_data_end( 684 struct sk_buff *skb, void *saved_data_end) 685 { 686 struct bpf_skb_data_end *cb = (struct bpf_skb_data_end *)skb->cb; 687 688 cb->data_end = saved_data_end; 689 } 690 691 static inline u8 *bpf_skb_cb(const struct sk_buff *skb) 692 { 693 /* eBPF programs may read/write skb->cb[] area to transfer meta 694 * data between tail calls. Since this also needs to work with 695 * tc, that scratch memory is mapped to qdisc_skb_cb's data area. 696 * 697 * In some socket filter cases, the cb unfortunately needs to be 698 * saved/restored so that protocol specific skb->cb[] data won't 699 * be lost. In any case, due to unpriviledged eBPF programs 700 * attached to sockets, we need to clear the bpf_skb_cb() area 701 * to not leak previous contents to user space. 702 */ 703 BUILD_BUG_ON(sizeof_field(struct __sk_buff, cb) != BPF_SKB_CB_LEN); 704 BUILD_BUG_ON(sizeof_field(struct __sk_buff, cb) != 705 sizeof_field(struct qdisc_skb_cb, data)); 706 707 return qdisc_skb_cb(skb)->data; 708 } 709 710 /* Must be invoked with migration disabled */ 711 static inline u32 __bpf_prog_run_save_cb(const struct bpf_prog *prog, 712 const void *ctx) 713 { 714 const struct sk_buff *skb = ctx; 715 u8 *cb_data = bpf_skb_cb(skb); 716 u8 cb_saved[BPF_SKB_CB_LEN]; 717 u32 res; 718 719 if (unlikely(prog->cb_access)) { 720 memcpy(cb_saved, cb_data, sizeof(cb_saved)); 721 memset(cb_data, 0, sizeof(cb_saved)); 722 } 723 724 res = bpf_prog_run(prog, skb); 725 726 if (unlikely(prog->cb_access)) 727 memcpy(cb_data, cb_saved, sizeof(cb_saved)); 728 729 return res; 730 } 731 732 static inline u32 bpf_prog_run_save_cb(const struct bpf_prog *prog, 733 struct sk_buff *skb) 734 { 735 u32 res; 736 737 migrate_disable(); 738 res = __bpf_prog_run_save_cb(prog, skb); 739 migrate_enable(); 740 return res; 741 } 742 743 static inline u32 bpf_prog_run_clear_cb(const struct bpf_prog *prog, 744 struct sk_buff *skb) 745 { 746 u8 *cb_data = bpf_skb_cb(skb); 747 u32 res; 748 749 if (unlikely(prog->cb_access)) 750 memset(cb_data, 0, BPF_SKB_CB_LEN); 751 752 res = bpf_prog_run_pin_on_cpu(prog, skb); 753 return res; 754 } 755 756 DECLARE_BPF_DISPATCHER(xdp) 757 758 DECLARE_STATIC_KEY_FALSE(bpf_master_redirect_enabled_key); 759 760 u32 xdp_master_redirect(struct xdp_buff *xdp); 761 762 static __always_inline u32 bpf_prog_run_xdp(const struct bpf_prog *prog, 763 struct xdp_buff *xdp) 764 { 765 /* Driver XDP hooks are invoked within a single NAPI poll cycle and thus 766 * under local_bh_disable(), which provides the needed RCU protection 767 * for accessing map entries. 768 */ 769 u32 act = __bpf_prog_run(prog, xdp, BPF_DISPATCHER_FUNC(xdp)); 770 771 if (static_branch_unlikely(&bpf_master_redirect_enabled_key)) { 772 if (act == XDP_TX && netif_is_bond_slave(xdp->rxq->dev)) 773 act = xdp_master_redirect(xdp); 774 } 775 776 return act; 777 } 778 779 void bpf_prog_change_xdp(struct bpf_prog *prev_prog, struct bpf_prog *prog); 780 781 static inline u32 bpf_prog_insn_size(const struct bpf_prog *prog) 782 { 783 return prog->len * sizeof(struct bpf_insn); 784 } 785 786 static inline u32 bpf_prog_tag_scratch_size(const struct bpf_prog *prog) 787 { 788 return round_up(bpf_prog_insn_size(prog) + 789 sizeof(__be64) + 1, SHA1_BLOCK_SIZE); 790 } 791 792 static inline unsigned int bpf_prog_size(unsigned int proglen) 793 { 794 return max(sizeof(struct bpf_prog), 795 offsetof(struct bpf_prog, insns[proglen])); 796 } 797 798 static inline bool bpf_prog_was_classic(const struct bpf_prog *prog) 799 { 800 /* When classic BPF programs have been loaded and the arch 801 * does not have a classic BPF JIT (anymore), they have been 802 * converted via bpf_migrate_filter() to eBPF and thus always 803 * have an unspec program type. 804 */ 805 return prog->type == BPF_PROG_TYPE_UNSPEC; 806 } 807 808 static inline u32 bpf_ctx_off_adjust_machine(u32 size) 809 { 810 const u32 size_machine = sizeof(unsigned long); 811 812 if (size > size_machine && size % size_machine == 0) 813 size = size_machine; 814 815 return size; 816 } 817 818 static inline bool 819 bpf_ctx_narrow_access_ok(u32 off, u32 size, u32 size_default) 820 { 821 return size <= size_default && (size & (size - 1)) == 0; 822 } 823 824 static inline u8 825 bpf_ctx_narrow_access_offset(u32 off, u32 size, u32 size_default) 826 { 827 u8 access_off = off & (size_default - 1); 828 829 #ifdef __LITTLE_ENDIAN 830 return access_off; 831 #else 832 return size_default - (access_off + size); 833 #endif 834 } 835 836 #define bpf_ctx_wide_access_ok(off, size, type, field) \ 837 (size == sizeof(__u64) && \ 838 off >= offsetof(type, field) && \ 839 off + sizeof(__u64) <= offsetofend(type, field) && \ 840 off % sizeof(__u64) == 0) 841 842 #define bpf_classic_proglen(fprog) (fprog->len * sizeof(fprog->filter[0])) 843 844 static inline void bpf_prog_lock_ro(struct bpf_prog *fp) 845 { 846 #ifndef CONFIG_BPF_JIT_ALWAYS_ON 847 if (!fp->jited) { 848 set_vm_flush_reset_perms(fp); 849 set_memory_ro((unsigned long)fp, fp->pages); 850 } 851 #endif 852 } 853 854 static inline void bpf_jit_binary_lock_ro(struct bpf_binary_header *hdr) 855 { 856 set_vm_flush_reset_perms(hdr); 857 set_memory_ro((unsigned long)hdr, hdr->size >> PAGE_SHIFT); 858 set_memory_x((unsigned long)hdr, hdr->size >> PAGE_SHIFT); 859 } 860 861 int sk_filter_trim_cap(struct sock *sk, struct sk_buff *skb, unsigned int cap); 862 static inline int sk_filter(struct sock *sk, struct sk_buff *skb) 863 { 864 return sk_filter_trim_cap(sk, skb, 1); 865 } 866 867 struct bpf_prog *bpf_prog_select_runtime(struct bpf_prog *fp, int *err); 868 void bpf_prog_free(struct bpf_prog *fp); 869 870 bool bpf_opcode_in_insntable(u8 code); 871 872 void bpf_prog_free_linfo(struct bpf_prog *prog); 873 void bpf_prog_fill_jited_linfo(struct bpf_prog *prog, 874 const u32 *insn_to_jit_off); 875 int bpf_prog_alloc_jited_linfo(struct bpf_prog *prog); 876 void bpf_prog_jit_attempt_done(struct bpf_prog *prog); 877 878 struct bpf_prog *bpf_prog_alloc(unsigned int size, gfp_t gfp_extra_flags); 879 struct bpf_prog *bpf_prog_alloc_no_stats(unsigned int size, gfp_t gfp_extra_flags); 880 struct bpf_prog *bpf_prog_realloc(struct bpf_prog *fp_old, unsigned int size, 881 gfp_t gfp_extra_flags); 882 void __bpf_prog_free(struct bpf_prog *fp); 883 884 static inline void bpf_prog_unlock_free(struct bpf_prog *fp) 885 { 886 __bpf_prog_free(fp); 887 } 888 889 typedef int (*bpf_aux_classic_check_t)(struct sock_filter *filter, 890 unsigned int flen); 891 892 int bpf_prog_create(struct bpf_prog **pfp, struct sock_fprog_kern *fprog); 893 int bpf_prog_create_from_user(struct bpf_prog **pfp, struct sock_fprog *fprog, 894 bpf_aux_classic_check_t trans, bool save_orig); 895 void bpf_prog_destroy(struct bpf_prog *fp); 896 897 int sk_attach_filter(struct sock_fprog *fprog, struct sock *sk); 898 int sk_attach_bpf(u32 ufd, struct sock *sk); 899 int sk_reuseport_attach_filter(struct sock_fprog *fprog, struct sock *sk); 900 int sk_reuseport_attach_bpf(u32 ufd, struct sock *sk); 901 void sk_reuseport_prog_free(struct bpf_prog *prog); 902 int sk_detach_filter(struct sock *sk); 903 int sk_get_filter(struct sock *sk, struct sock_filter __user *filter, 904 unsigned int len); 905 906 bool sk_filter_charge(struct sock *sk, struct sk_filter *fp); 907 void sk_filter_uncharge(struct sock *sk, struct sk_filter *fp); 908 909 u64 __bpf_call_base(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5); 910 #define __bpf_call_base_args \ 911 ((u64 (*)(u64, u64, u64, u64, u64, const struct bpf_insn *)) \ 912 (void *)__bpf_call_base) 913 914 struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog); 915 void bpf_jit_compile(struct bpf_prog *prog); 916 bool bpf_jit_needs_zext(void); 917 bool bpf_jit_supports_kfunc_call(void); 918 bool bpf_helper_changes_pkt_data(void *func); 919 920 static inline bool bpf_dump_raw_ok(const struct cred *cred) 921 { 922 /* Reconstruction of call-sites is dependent on kallsyms, 923 * thus make dump the same restriction. 924 */ 925 return kallsyms_show_value(cred); 926 } 927 928 struct bpf_prog *bpf_patch_insn_single(struct bpf_prog *prog, u32 off, 929 const struct bpf_insn *patch, u32 len); 930 int bpf_remove_insns(struct bpf_prog *prog, u32 off, u32 cnt); 931 932 void bpf_clear_redirect_map(struct bpf_map *map); 933 934 static inline bool xdp_return_frame_no_direct(void) 935 { 936 struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info); 937 938 return ri->kern_flags & BPF_RI_F_RF_NO_DIRECT; 939 } 940 941 static inline void xdp_set_return_frame_no_direct(void) 942 { 943 struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info); 944 945 ri->kern_flags |= BPF_RI_F_RF_NO_DIRECT; 946 } 947 948 static inline void xdp_clear_return_frame_no_direct(void) 949 { 950 struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info); 951 952 ri->kern_flags &= ~BPF_RI_F_RF_NO_DIRECT; 953 } 954 955 static inline int xdp_ok_fwd_dev(const struct net_device *fwd, 956 unsigned int pktlen) 957 { 958 unsigned int len; 959 960 if (unlikely(!(fwd->flags & IFF_UP))) 961 return -ENETDOWN; 962 963 len = fwd->mtu + fwd->hard_header_len + VLAN_HLEN; 964 if (pktlen > len) 965 return -EMSGSIZE; 966 967 return 0; 968 } 969 970 /* The pair of xdp_do_redirect and xdp_do_flush MUST be called in the 971 * same cpu context. Further for best results no more than a single map 972 * for the do_redirect/do_flush pair should be used. This limitation is 973 * because we only track one map and force a flush when the map changes. 974 * This does not appear to be a real limitation for existing software. 975 */ 976 int xdp_do_generic_redirect(struct net_device *dev, struct sk_buff *skb, 977 struct xdp_buff *xdp, struct bpf_prog *prog); 978 int xdp_do_redirect(struct net_device *dev, 979 struct xdp_buff *xdp, 980 struct bpf_prog *prog); 981 int xdp_do_redirect_frame(struct net_device *dev, 982 struct xdp_buff *xdp, 983 struct xdp_frame *xdpf, 984 struct bpf_prog *prog); 985 void xdp_do_flush(void); 986 987 /* The xdp_do_flush_map() helper has been renamed to drop the _map suffix, as 988 * it is no longer only flushing maps. Keep this define for compatibility 989 * until all drivers are updated - do not use xdp_do_flush_map() in new code! 990 */ 991 #define xdp_do_flush_map xdp_do_flush 992 993 void bpf_warn_invalid_xdp_action(struct net_device *dev, struct bpf_prog *prog, u32 act); 994 995 #ifdef CONFIG_INET 996 struct sock *bpf_run_sk_reuseport(struct sock_reuseport *reuse, struct sock *sk, 997 struct bpf_prog *prog, struct sk_buff *skb, 998 struct sock *migrating_sk, 999 u32 hash); 1000 #else 1001 static inline struct sock * 1002 bpf_run_sk_reuseport(struct sock_reuseport *reuse, struct sock *sk, 1003 struct bpf_prog *prog, struct sk_buff *skb, 1004 struct sock *migrating_sk, 1005 u32 hash) 1006 { 1007 return NULL; 1008 } 1009 #endif 1010 1011 #ifdef CONFIG_BPF_JIT 1012 extern int bpf_jit_enable; 1013 extern int bpf_jit_harden; 1014 extern int bpf_jit_kallsyms; 1015 extern long bpf_jit_limit; 1016 extern long bpf_jit_limit_max; 1017 1018 typedef void (*bpf_jit_fill_hole_t)(void *area, unsigned int size); 1019 1020 struct bpf_binary_header * 1021 bpf_jit_binary_alloc(unsigned int proglen, u8 **image_ptr, 1022 unsigned int alignment, 1023 bpf_jit_fill_hole_t bpf_fill_ill_insns); 1024 void bpf_jit_binary_free(struct bpf_binary_header *hdr); 1025 u64 bpf_jit_alloc_exec_limit(void); 1026 void *bpf_jit_alloc_exec(unsigned long size); 1027 void bpf_jit_free_exec(void *addr); 1028 void bpf_jit_free(struct bpf_prog *fp); 1029 1030 struct bpf_binary_header * 1031 bpf_jit_binary_pack_alloc(unsigned int proglen, u8 **ro_image, 1032 unsigned int alignment, 1033 struct bpf_binary_header **rw_hdr, 1034 u8 **rw_image, 1035 bpf_jit_fill_hole_t bpf_fill_ill_insns); 1036 int bpf_jit_binary_pack_finalize(struct bpf_prog *prog, 1037 struct bpf_binary_header *ro_header, 1038 struct bpf_binary_header *rw_header); 1039 void bpf_jit_binary_pack_free(struct bpf_binary_header *ro_header, 1040 struct bpf_binary_header *rw_header); 1041 1042 int bpf_jit_add_poke_descriptor(struct bpf_prog *prog, 1043 struct bpf_jit_poke_descriptor *poke); 1044 1045 int bpf_jit_get_func_addr(const struct bpf_prog *prog, 1046 const struct bpf_insn *insn, bool extra_pass, 1047 u64 *func_addr, bool *func_addr_fixed); 1048 1049 struct bpf_prog *bpf_jit_blind_constants(struct bpf_prog *fp); 1050 void bpf_jit_prog_release_other(struct bpf_prog *fp, struct bpf_prog *fp_other); 1051 1052 static inline void bpf_jit_dump(unsigned int flen, unsigned int proglen, 1053 u32 pass, void *image) 1054 { 1055 pr_err("flen=%u proglen=%u pass=%u image=%pK from=%s pid=%d\n", flen, 1056 proglen, pass, image, current->comm, task_pid_nr(current)); 1057 1058 if (image) 1059 print_hex_dump(KERN_ERR, "JIT code: ", DUMP_PREFIX_OFFSET, 1060 16, 1, image, proglen, false); 1061 } 1062 1063 static inline bool bpf_jit_is_ebpf(void) 1064 { 1065 # ifdef CONFIG_HAVE_EBPF_JIT 1066 return true; 1067 # else 1068 return false; 1069 # endif 1070 } 1071 1072 static inline bool ebpf_jit_enabled(void) 1073 { 1074 return bpf_jit_enable && bpf_jit_is_ebpf(); 1075 } 1076 1077 static inline bool bpf_prog_ebpf_jited(const struct bpf_prog *fp) 1078 { 1079 return fp->jited && bpf_jit_is_ebpf(); 1080 } 1081 1082 static inline bool bpf_jit_blinding_enabled(struct bpf_prog *prog) 1083 { 1084 /* These are the prerequisites, should someone ever have the 1085 * idea to call blinding outside of them, we make sure to 1086 * bail out. 1087 */ 1088 if (!bpf_jit_is_ebpf()) 1089 return false; 1090 if (!prog->jit_requested) 1091 return false; 1092 if (!bpf_jit_harden) 1093 return false; 1094 if (bpf_jit_harden == 1 && capable(CAP_SYS_ADMIN)) 1095 return false; 1096 1097 return true; 1098 } 1099 1100 static inline bool bpf_jit_kallsyms_enabled(void) 1101 { 1102 /* There are a couple of corner cases where kallsyms should 1103 * not be enabled f.e. on hardening. 1104 */ 1105 if (bpf_jit_harden) 1106 return false; 1107 if (!bpf_jit_kallsyms) 1108 return false; 1109 if (bpf_jit_kallsyms == 1) 1110 return true; 1111 1112 return false; 1113 } 1114 1115 const char *__bpf_address_lookup(unsigned long addr, unsigned long *size, 1116 unsigned long *off, char *sym); 1117 bool is_bpf_text_address(unsigned long addr); 1118 int bpf_get_kallsym(unsigned int symnum, unsigned long *value, char *type, 1119 char *sym); 1120 1121 static inline const char * 1122 bpf_address_lookup(unsigned long addr, unsigned long *size, 1123 unsigned long *off, char **modname, char *sym) 1124 { 1125 const char *ret = __bpf_address_lookup(addr, size, off, sym); 1126 1127 if (ret && modname) 1128 *modname = NULL; 1129 return ret; 1130 } 1131 1132 void bpf_prog_kallsyms_add(struct bpf_prog *fp); 1133 void bpf_prog_kallsyms_del(struct bpf_prog *fp); 1134 1135 #else /* CONFIG_BPF_JIT */ 1136 1137 static inline bool ebpf_jit_enabled(void) 1138 { 1139 return false; 1140 } 1141 1142 static inline bool bpf_jit_blinding_enabled(struct bpf_prog *prog) 1143 { 1144 return false; 1145 } 1146 1147 static inline bool bpf_prog_ebpf_jited(const struct bpf_prog *fp) 1148 { 1149 return false; 1150 } 1151 1152 static inline int 1153 bpf_jit_add_poke_descriptor(struct bpf_prog *prog, 1154 struct bpf_jit_poke_descriptor *poke) 1155 { 1156 return -ENOTSUPP; 1157 } 1158 1159 static inline void bpf_jit_free(struct bpf_prog *fp) 1160 { 1161 bpf_prog_unlock_free(fp); 1162 } 1163 1164 static inline bool bpf_jit_kallsyms_enabled(void) 1165 { 1166 return false; 1167 } 1168 1169 static inline const char * 1170 __bpf_address_lookup(unsigned long addr, unsigned long *size, 1171 unsigned long *off, char *sym) 1172 { 1173 return NULL; 1174 } 1175 1176 static inline bool is_bpf_text_address(unsigned long addr) 1177 { 1178 return false; 1179 } 1180 1181 static inline int bpf_get_kallsym(unsigned int symnum, unsigned long *value, 1182 char *type, char *sym) 1183 { 1184 return -ERANGE; 1185 } 1186 1187 static inline const char * 1188 bpf_address_lookup(unsigned long addr, unsigned long *size, 1189 unsigned long *off, char **modname, char *sym) 1190 { 1191 return NULL; 1192 } 1193 1194 static inline void bpf_prog_kallsyms_add(struct bpf_prog *fp) 1195 { 1196 } 1197 1198 static inline void bpf_prog_kallsyms_del(struct bpf_prog *fp) 1199 { 1200 } 1201 1202 #endif /* CONFIG_BPF_JIT */ 1203 1204 void bpf_prog_kallsyms_del_all(struct bpf_prog *fp); 1205 1206 #define BPF_ANC BIT(15) 1207 1208 static inline bool bpf_needs_clear_a(const struct sock_filter *first) 1209 { 1210 switch (first->code) { 1211 case BPF_RET | BPF_K: 1212 case BPF_LD | BPF_W | BPF_LEN: 1213 return false; 1214 1215 case BPF_LD | BPF_W | BPF_ABS: 1216 case BPF_LD | BPF_H | BPF_ABS: 1217 case BPF_LD | BPF_B | BPF_ABS: 1218 if (first->k == SKF_AD_OFF + SKF_AD_ALU_XOR_X) 1219 return true; 1220 return false; 1221 1222 default: 1223 return true; 1224 } 1225 } 1226 1227 static inline u16 bpf_anc_helper(const struct sock_filter *ftest) 1228 { 1229 BUG_ON(ftest->code & BPF_ANC); 1230 1231 switch (ftest->code) { 1232 case BPF_LD | BPF_W | BPF_ABS: 1233 case BPF_LD | BPF_H | BPF_ABS: 1234 case BPF_LD | BPF_B | BPF_ABS: 1235 #define BPF_ANCILLARY(CODE) case SKF_AD_OFF + SKF_AD_##CODE: \ 1236 return BPF_ANC | SKF_AD_##CODE 1237 switch (ftest->k) { 1238 BPF_ANCILLARY(PROTOCOL); 1239 BPF_ANCILLARY(PKTTYPE); 1240 BPF_ANCILLARY(IFINDEX); 1241 BPF_ANCILLARY(NLATTR); 1242 BPF_ANCILLARY(NLATTR_NEST); 1243 BPF_ANCILLARY(MARK); 1244 BPF_ANCILLARY(QUEUE); 1245 BPF_ANCILLARY(HATYPE); 1246 BPF_ANCILLARY(RXHASH); 1247 BPF_ANCILLARY(CPU); 1248 BPF_ANCILLARY(ALU_XOR_X); 1249 BPF_ANCILLARY(VLAN_TAG); 1250 BPF_ANCILLARY(VLAN_TAG_PRESENT); 1251 BPF_ANCILLARY(PAY_OFFSET); 1252 BPF_ANCILLARY(RANDOM); 1253 BPF_ANCILLARY(VLAN_TPID); 1254 } 1255 fallthrough; 1256 default: 1257 return ftest->code; 1258 } 1259 } 1260 1261 void *bpf_internal_load_pointer_neg_helper(const struct sk_buff *skb, 1262 int k, unsigned int size); 1263 1264 static inline int bpf_tell_extensions(void) 1265 { 1266 return SKF_AD_MAX; 1267 } 1268 1269 struct bpf_sock_addr_kern { 1270 struct sock *sk; 1271 struct sockaddr *uaddr; 1272 /* Temporary "register" to make indirect stores to nested structures 1273 * defined above. We need three registers to make such a store, but 1274 * only two (src and dst) are available at convert_ctx_access time 1275 */ 1276 u64 tmp_reg; 1277 void *t_ctx; /* Attach type specific context. */ 1278 }; 1279 1280 struct bpf_sock_ops_kern { 1281 struct sock *sk; 1282 union { 1283 u32 args[4]; 1284 u32 reply; 1285 u32 replylong[4]; 1286 }; 1287 struct sk_buff *syn_skb; 1288 struct sk_buff *skb; 1289 void *skb_data_end; 1290 u8 op; 1291 u8 is_fullsock; 1292 u8 remaining_opt_len; 1293 u64 temp; /* temp and everything after is not 1294 * initialized to 0 before calling 1295 * the BPF program. New fields that 1296 * should be initialized to 0 should 1297 * be inserted before temp. 1298 * temp is scratch storage used by 1299 * sock_ops_convert_ctx_access 1300 * as temporary storage of a register. 1301 */ 1302 }; 1303 1304 struct bpf_sysctl_kern { 1305 struct ctl_table_header *head; 1306 struct ctl_table *table; 1307 void *cur_val; 1308 size_t cur_len; 1309 void *new_val; 1310 size_t new_len; 1311 int new_updated; 1312 int write; 1313 loff_t *ppos; 1314 /* Temporary "register" for indirect stores to ppos. */ 1315 u64 tmp_reg; 1316 }; 1317 1318 #define BPF_SOCKOPT_KERN_BUF_SIZE 32 1319 struct bpf_sockopt_buf { 1320 u8 data[BPF_SOCKOPT_KERN_BUF_SIZE]; 1321 }; 1322 1323 struct bpf_sockopt_kern { 1324 struct sock *sk; 1325 u8 *optval; 1326 u8 *optval_end; 1327 s32 level; 1328 s32 optname; 1329 s32 optlen; 1330 /* for retval in struct bpf_cg_run_ctx */ 1331 struct task_struct *current_task; 1332 /* Temporary "register" for indirect stores to ppos. */ 1333 u64 tmp_reg; 1334 }; 1335 1336 int copy_bpf_fprog_from_user(struct sock_fprog *dst, sockptr_t src, int len); 1337 1338 struct bpf_sk_lookup_kern { 1339 u16 family; 1340 u16 protocol; 1341 __be16 sport; 1342 u16 dport; 1343 struct { 1344 __be32 saddr; 1345 __be32 daddr; 1346 } v4; 1347 struct { 1348 const struct in6_addr *saddr; 1349 const struct in6_addr *daddr; 1350 } v6; 1351 struct sock *selected_sk; 1352 u32 ingress_ifindex; 1353 bool no_reuseport; 1354 }; 1355 1356 extern struct static_key_false bpf_sk_lookup_enabled; 1357 1358 /* Runners for BPF_SK_LOOKUP programs to invoke on socket lookup. 1359 * 1360 * Allowed return values for a BPF SK_LOOKUP program are SK_PASS and 1361 * SK_DROP. Their meaning is as follows: 1362 * 1363 * SK_PASS && ctx.selected_sk != NULL: use selected_sk as lookup result 1364 * SK_PASS && ctx.selected_sk == NULL: continue to htable-based socket lookup 1365 * SK_DROP : terminate lookup with -ECONNREFUSED 1366 * 1367 * This macro aggregates return values and selected sockets from 1368 * multiple BPF programs according to following rules in order: 1369 * 1370 * 1. If any program returned SK_PASS and a non-NULL ctx.selected_sk, 1371 * macro result is SK_PASS and last ctx.selected_sk is used. 1372 * 2. If any program returned SK_DROP return value, 1373 * macro result is SK_DROP. 1374 * 3. Otherwise result is SK_PASS and ctx.selected_sk is NULL. 1375 * 1376 * Caller must ensure that the prog array is non-NULL, and that the 1377 * array as well as the programs it contains remain valid. 1378 */ 1379 #define BPF_PROG_SK_LOOKUP_RUN_ARRAY(array, ctx, func) \ 1380 ({ \ 1381 struct bpf_sk_lookup_kern *_ctx = &(ctx); \ 1382 struct bpf_prog_array_item *_item; \ 1383 struct sock *_selected_sk = NULL; \ 1384 bool _no_reuseport = false; \ 1385 struct bpf_prog *_prog; \ 1386 bool _all_pass = true; \ 1387 u32 _ret; \ 1388 \ 1389 migrate_disable(); \ 1390 _item = &(array)->items[0]; \ 1391 while ((_prog = READ_ONCE(_item->prog))) { \ 1392 /* restore most recent selection */ \ 1393 _ctx->selected_sk = _selected_sk; \ 1394 _ctx->no_reuseport = _no_reuseport; \ 1395 \ 1396 _ret = func(_prog, _ctx); \ 1397 if (_ret == SK_PASS && _ctx->selected_sk) { \ 1398 /* remember last non-NULL socket */ \ 1399 _selected_sk = _ctx->selected_sk; \ 1400 _no_reuseport = _ctx->no_reuseport; \ 1401 } else if (_ret == SK_DROP && _all_pass) { \ 1402 _all_pass = false; \ 1403 } \ 1404 _item++; \ 1405 } \ 1406 _ctx->selected_sk = _selected_sk; \ 1407 _ctx->no_reuseport = _no_reuseport; \ 1408 migrate_enable(); \ 1409 _all_pass || _selected_sk ? SK_PASS : SK_DROP; \ 1410 }) 1411 1412 static inline bool bpf_sk_lookup_run_v4(struct net *net, int protocol, 1413 const __be32 saddr, const __be16 sport, 1414 const __be32 daddr, const u16 dport, 1415 const int ifindex, struct sock **psk) 1416 { 1417 struct bpf_prog_array *run_array; 1418 struct sock *selected_sk = NULL; 1419 bool no_reuseport = false; 1420 1421 rcu_read_lock(); 1422 run_array = rcu_dereference(net->bpf.run_array[NETNS_BPF_SK_LOOKUP]); 1423 if (run_array) { 1424 struct bpf_sk_lookup_kern ctx = { 1425 .family = AF_INET, 1426 .protocol = protocol, 1427 .v4.saddr = saddr, 1428 .v4.daddr = daddr, 1429 .sport = sport, 1430 .dport = dport, 1431 .ingress_ifindex = ifindex, 1432 }; 1433 u32 act; 1434 1435 act = BPF_PROG_SK_LOOKUP_RUN_ARRAY(run_array, ctx, bpf_prog_run); 1436 if (act == SK_PASS) { 1437 selected_sk = ctx.selected_sk; 1438 no_reuseport = ctx.no_reuseport; 1439 } else { 1440 selected_sk = ERR_PTR(-ECONNREFUSED); 1441 } 1442 } 1443 rcu_read_unlock(); 1444 *psk = selected_sk; 1445 return no_reuseport; 1446 } 1447 1448 #if IS_ENABLED(CONFIG_IPV6) 1449 static inline bool bpf_sk_lookup_run_v6(struct net *net, int protocol, 1450 const struct in6_addr *saddr, 1451 const __be16 sport, 1452 const struct in6_addr *daddr, 1453 const u16 dport, 1454 const int ifindex, struct sock **psk) 1455 { 1456 struct bpf_prog_array *run_array; 1457 struct sock *selected_sk = NULL; 1458 bool no_reuseport = false; 1459 1460 rcu_read_lock(); 1461 run_array = rcu_dereference(net->bpf.run_array[NETNS_BPF_SK_LOOKUP]); 1462 if (run_array) { 1463 struct bpf_sk_lookup_kern ctx = { 1464 .family = AF_INET6, 1465 .protocol = protocol, 1466 .v6.saddr = saddr, 1467 .v6.daddr = daddr, 1468 .sport = sport, 1469 .dport = dport, 1470 .ingress_ifindex = ifindex, 1471 }; 1472 u32 act; 1473 1474 act = BPF_PROG_SK_LOOKUP_RUN_ARRAY(run_array, ctx, bpf_prog_run); 1475 if (act == SK_PASS) { 1476 selected_sk = ctx.selected_sk; 1477 no_reuseport = ctx.no_reuseport; 1478 } else { 1479 selected_sk = ERR_PTR(-ECONNREFUSED); 1480 } 1481 } 1482 rcu_read_unlock(); 1483 *psk = selected_sk; 1484 return no_reuseport; 1485 } 1486 #endif /* IS_ENABLED(CONFIG_IPV6) */ 1487 1488 static __always_inline int __bpf_xdp_redirect_map(struct bpf_map *map, u32 ifindex, 1489 u64 flags, const u64 flag_mask, 1490 void *lookup_elem(struct bpf_map *map, u32 key)) 1491 { 1492 struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info); 1493 const u64 action_mask = XDP_ABORTED | XDP_DROP | XDP_PASS | XDP_TX; 1494 1495 /* Lower bits of the flags are used as return code on lookup failure */ 1496 if (unlikely(flags & ~(action_mask | flag_mask))) 1497 return XDP_ABORTED; 1498 1499 ri->tgt_value = lookup_elem(map, ifindex); 1500 if (unlikely(!ri->tgt_value) && !(flags & BPF_F_BROADCAST)) { 1501 /* If the lookup fails we want to clear out the state in the 1502 * redirect_info struct completely, so that if an eBPF program 1503 * performs multiple lookups, the last one always takes 1504 * precedence. 1505 */ 1506 ri->map_id = INT_MAX; /* Valid map id idr range: [1,INT_MAX[ */ 1507 ri->map_type = BPF_MAP_TYPE_UNSPEC; 1508 return flags & action_mask; 1509 } 1510 1511 ri->tgt_index = ifindex; 1512 ri->map_id = map->id; 1513 ri->map_type = map->map_type; 1514 1515 if (flags & BPF_F_BROADCAST) { 1516 WRITE_ONCE(ri->map, map); 1517 ri->flags = flags; 1518 } else { 1519 WRITE_ONCE(ri->map, NULL); 1520 ri->flags = 0; 1521 } 1522 1523 return XDP_REDIRECT; 1524 } 1525 1526 #endif /* __LINUX_FILTER_H__ */ 1527