at v6.11 50 kB view raw
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 32struct sk_buff; 33struct sock; 34struct seccomp_data; 35struct bpf_prog_aux; 36struct xdp_rxq_info; 37struct xdp_buff; 38struct sock_reuseport; 39struct ctl_table; 40struct 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 198static 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 248static 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 */ 256static 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. */ 627struct compat_sock_fprog { 628 u16 len; 629 compat_uptr_t filter; /* struct sock_filter * */ 630}; 631 632struct 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 640struct bpf_binary_header { 641 u32 size; 642 u8 image[] __aligned(BPF_IMAGE_ALIGNMENT); 643}; 644 645struct 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 652struct sk_filter { 653 refcount_t refcnt; 654 struct rcu_head rcu; 655 struct bpf_prog *prog; 656}; 657 658DECLARE_STATIC_KEY_FALSE(bpf_stats_enabled_key); 659 660extern struct mutex nf_conn_btf_access_lock; 661extern int (*nfct_btf_struct_access)(struct bpf_verifier_log *log, 662 const struct bpf_reg_state *reg, 663 int off, int size); 664 665typedef 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 670static __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 696static __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 */ 709static 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 722struct bpf_skb_data_end { 723 struct qdisc_skb_cb qdisc_cb; 724 void *data_meta; 725 void *data_end; 726}; 727 728struct bpf_nh_params { 729 u32 nh_family; 730 union { 731 u32 ipv4_nh; 732 struct in6_addr ipv6_nh; 733 }; 734}; 735 736/* flags for bpf_redirect_info kern_flags */ 737#define BPF_RI_F_RF_NO_DIRECT BIT(0) /* no napi_direct on return_frame */ 738#define BPF_RI_F_RI_INIT BIT(1) 739#define BPF_RI_F_CPU_MAP_INIT BIT(2) 740#define BPF_RI_F_DEV_MAP_INIT BIT(3) 741#define BPF_RI_F_XSK_MAP_INIT BIT(4) 742 743struct bpf_redirect_info { 744 u64 tgt_index; 745 void *tgt_value; 746 struct bpf_map *map; 747 u32 flags; 748 u32 map_id; 749 enum bpf_map_type map_type; 750 struct bpf_nh_params nh; 751 u32 kern_flags; 752}; 753 754struct bpf_net_context { 755 struct bpf_redirect_info ri; 756 struct list_head cpu_map_flush_list; 757 struct list_head dev_map_flush_list; 758 struct list_head xskmap_map_flush_list; 759}; 760 761static inline struct bpf_net_context *bpf_net_ctx_set(struct bpf_net_context *bpf_net_ctx) 762{ 763 struct task_struct *tsk = current; 764 765 if (tsk->bpf_net_context != NULL) 766 return NULL; 767 bpf_net_ctx->ri.kern_flags = 0; 768 769 tsk->bpf_net_context = bpf_net_ctx; 770 return bpf_net_ctx; 771} 772 773static inline void bpf_net_ctx_clear(struct bpf_net_context *bpf_net_ctx) 774{ 775 if (bpf_net_ctx) 776 current->bpf_net_context = NULL; 777} 778 779static inline struct bpf_net_context *bpf_net_ctx_get(void) 780{ 781 return current->bpf_net_context; 782} 783 784static inline struct bpf_redirect_info *bpf_net_ctx_get_ri(void) 785{ 786 struct bpf_net_context *bpf_net_ctx = bpf_net_ctx_get(); 787 788 if (!(bpf_net_ctx->ri.kern_flags & BPF_RI_F_RI_INIT)) { 789 memset(&bpf_net_ctx->ri, 0, offsetof(struct bpf_net_context, ri.nh)); 790 bpf_net_ctx->ri.kern_flags |= BPF_RI_F_RI_INIT; 791 } 792 793 return &bpf_net_ctx->ri; 794} 795 796static inline struct list_head *bpf_net_ctx_get_cpu_map_flush_list(void) 797{ 798 struct bpf_net_context *bpf_net_ctx = bpf_net_ctx_get(); 799 800 if (!(bpf_net_ctx->ri.kern_flags & BPF_RI_F_CPU_MAP_INIT)) { 801 INIT_LIST_HEAD(&bpf_net_ctx->cpu_map_flush_list); 802 bpf_net_ctx->ri.kern_flags |= BPF_RI_F_CPU_MAP_INIT; 803 } 804 805 return &bpf_net_ctx->cpu_map_flush_list; 806} 807 808static inline struct list_head *bpf_net_ctx_get_dev_flush_list(void) 809{ 810 struct bpf_net_context *bpf_net_ctx = bpf_net_ctx_get(); 811 812 if (!(bpf_net_ctx->ri.kern_flags & BPF_RI_F_DEV_MAP_INIT)) { 813 INIT_LIST_HEAD(&bpf_net_ctx->dev_map_flush_list); 814 bpf_net_ctx->ri.kern_flags |= BPF_RI_F_DEV_MAP_INIT; 815 } 816 817 return &bpf_net_ctx->dev_map_flush_list; 818} 819 820static inline struct list_head *bpf_net_ctx_get_xskmap_flush_list(void) 821{ 822 struct bpf_net_context *bpf_net_ctx = bpf_net_ctx_get(); 823 824 if (!(bpf_net_ctx->ri.kern_flags & BPF_RI_F_XSK_MAP_INIT)) { 825 INIT_LIST_HEAD(&bpf_net_ctx->xskmap_map_flush_list); 826 bpf_net_ctx->ri.kern_flags |= BPF_RI_F_XSK_MAP_INIT; 827 } 828 829 return &bpf_net_ctx->xskmap_map_flush_list; 830} 831 832static inline void bpf_net_ctx_get_all_used_flush_lists(struct list_head **lh_map, 833 struct list_head **lh_dev, 834 struct list_head **lh_xsk) 835{ 836 struct bpf_net_context *bpf_net_ctx = bpf_net_ctx_get(); 837 u32 kern_flags = bpf_net_ctx->ri.kern_flags; 838 struct list_head *lh; 839 840 *lh_map = *lh_dev = *lh_xsk = NULL; 841 842 if (!IS_ENABLED(CONFIG_BPF_SYSCALL)) 843 return; 844 845 lh = &bpf_net_ctx->dev_map_flush_list; 846 if (kern_flags & BPF_RI_F_DEV_MAP_INIT && !list_empty(lh)) 847 *lh_dev = lh; 848 849 lh = &bpf_net_ctx->cpu_map_flush_list; 850 if (kern_flags & BPF_RI_F_CPU_MAP_INIT && !list_empty(lh)) 851 *lh_map = lh; 852 853 lh = &bpf_net_ctx->xskmap_map_flush_list; 854 if (IS_ENABLED(CONFIG_XDP_SOCKETS) && 855 kern_flags & BPF_RI_F_XSK_MAP_INIT && !list_empty(lh)) 856 *lh_xsk = lh; 857} 858 859/* Compute the linear packet data range [data, data_end) which 860 * will be accessed by various program types (cls_bpf, act_bpf, 861 * lwt, ...). Subsystems allowing direct data access must (!) 862 * ensure that cb[] area can be written to when BPF program is 863 * invoked (otherwise cb[] save/restore is necessary). 864 */ 865static inline void bpf_compute_data_pointers(struct sk_buff *skb) 866{ 867 struct bpf_skb_data_end *cb = (struct bpf_skb_data_end *)skb->cb; 868 869 BUILD_BUG_ON(sizeof(*cb) > sizeof_field(struct sk_buff, cb)); 870 cb->data_meta = skb->data - skb_metadata_len(skb); 871 cb->data_end = skb->data + skb_headlen(skb); 872} 873 874/* Similar to bpf_compute_data_pointers(), except that save orginal 875 * data in cb->data and cb->meta_data for restore. 876 */ 877static inline void bpf_compute_and_save_data_end( 878 struct sk_buff *skb, void **saved_data_end) 879{ 880 struct bpf_skb_data_end *cb = (struct bpf_skb_data_end *)skb->cb; 881 882 *saved_data_end = cb->data_end; 883 cb->data_end = skb->data + skb_headlen(skb); 884} 885 886/* Restore data saved by bpf_compute_and_save_data_end(). */ 887static inline void bpf_restore_data_end( 888 struct sk_buff *skb, void *saved_data_end) 889{ 890 struct bpf_skb_data_end *cb = (struct bpf_skb_data_end *)skb->cb; 891 892 cb->data_end = saved_data_end; 893} 894 895static inline u8 *bpf_skb_cb(const struct sk_buff *skb) 896{ 897 /* eBPF programs may read/write skb->cb[] area to transfer meta 898 * data between tail calls. Since this also needs to work with 899 * tc, that scratch memory is mapped to qdisc_skb_cb's data area. 900 * 901 * In some socket filter cases, the cb unfortunately needs to be 902 * saved/restored so that protocol specific skb->cb[] data won't 903 * be lost. In any case, due to unpriviledged eBPF programs 904 * attached to sockets, we need to clear the bpf_skb_cb() area 905 * to not leak previous contents to user space. 906 */ 907 BUILD_BUG_ON(sizeof_field(struct __sk_buff, cb) != BPF_SKB_CB_LEN); 908 BUILD_BUG_ON(sizeof_field(struct __sk_buff, cb) != 909 sizeof_field(struct qdisc_skb_cb, data)); 910 911 return qdisc_skb_cb(skb)->data; 912} 913 914/* Must be invoked with migration disabled */ 915static inline u32 __bpf_prog_run_save_cb(const struct bpf_prog *prog, 916 const void *ctx) 917{ 918 const struct sk_buff *skb = ctx; 919 u8 *cb_data = bpf_skb_cb(skb); 920 u8 cb_saved[BPF_SKB_CB_LEN]; 921 u32 res; 922 923 if (unlikely(prog->cb_access)) { 924 memcpy(cb_saved, cb_data, sizeof(cb_saved)); 925 memset(cb_data, 0, sizeof(cb_saved)); 926 } 927 928 res = bpf_prog_run(prog, skb); 929 930 if (unlikely(prog->cb_access)) 931 memcpy(cb_data, cb_saved, sizeof(cb_saved)); 932 933 return res; 934} 935 936static inline u32 bpf_prog_run_save_cb(const struct bpf_prog *prog, 937 struct sk_buff *skb) 938{ 939 u32 res; 940 941 migrate_disable(); 942 res = __bpf_prog_run_save_cb(prog, skb); 943 migrate_enable(); 944 return res; 945} 946 947static inline u32 bpf_prog_run_clear_cb(const struct bpf_prog *prog, 948 struct sk_buff *skb) 949{ 950 u8 *cb_data = bpf_skb_cb(skb); 951 u32 res; 952 953 if (unlikely(prog->cb_access)) 954 memset(cb_data, 0, BPF_SKB_CB_LEN); 955 956 res = bpf_prog_run_pin_on_cpu(prog, skb); 957 return res; 958} 959 960DECLARE_BPF_DISPATCHER(xdp) 961 962DECLARE_STATIC_KEY_FALSE(bpf_master_redirect_enabled_key); 963 964u32 xdp_master_redirect(struct xdp_buff *xdp); 965 966void bpf_prog_change_xdp(struct bpf_prog *prev_prog, struct bpf_prog *prog); 967 968static inline u32 bpf_prog_insn_size(const struct bpf_prog *prog) 969{ 970 return prog->len * sizeof(struct bpf_insn); 971} 972 973static inline u32 bpf_prog_tag_scratch_size(const struct bpf_prog *prog) 974{ 975 return round_up(bpf_prog_insn_size(prog) + 976 sizeof(__be64) + 1, SHA1_BLOCK_SIZE); 977} 978 979static inline unsigned int bpf_prog_size(unsigned int proglen) 980{ 981 return max(sizeof(struct bpf_prog), 982 offsetof(struct bpf_prog, insns[proglen])); 983} 984 985static inline bool bpf_prog_was_classic(const struct bpf_prog *prog) 986{ 987 /* When classic BPF programs have been loaded and the arch 988 * does not have a classic BPF JIT (anymore), they have been 989 * converted via bpf_migrate_filter() to eBPF and thus always 990 * have an unspec program type. 991 */ 992 return prog->type == BPF_PROG_TYPE_UNSPEC; 993} 994 995static inline u32 bpf_ctx_off_adjust_machine(u32 size) 996{ 997 const u32 size_machine = sizeof(unsigned long); 998 999 if (size > size_machine && size % size_machine == 0) 1000 size = size_machine; 1001 1002 return size; 1003} 1004 1005static inline bool 1006bpf_ctx_narrow_access_ok(u32 off, u32 size, u32 size_default) 1007{ 1008 return size <= size_default && (size & (size - 1)) == 0; 1009} 1010 1011static inline u8 1012bpf_ctx_narrow_access_offset(u32 off, u32 size, u32 size_default) 1013{ 1014 u8 access_off = off & (size_default - 1); 1015 1016#ifdef __LITTLE_ENDIAN 1017 return access_off; 1018#else 1019 return size_default - (access_off + size); 1020#endif 1021} 1022 1023#define bpf_ctx_wide_access_ok(off, size, type, field) \ 1024 (size == sizeof(__u64) && \ 1025 off >= offsetof(type, field) && \ 1026 off + sizeof(__u64) <= offsetofend(type, field) && \ 1027 off % sizeof(__u64) == 0) 1028 1029#define bpf_classic_proglen(fprog) (fprog->len * sizeof(fprog->filter[0])) 1030 1031static inline int __must_check bpf_prog_lock_ro(struct bpf_prog *fp) 1032{ 1033#ifndef CONFIG_BPF_JIT_ALWAYS_ON 1034 if (!fp->jited) { 1035 set_vm_flush_reset_perms(fp); 1036 return set_memory_ro((unsigned long)fp, fp->pages); 1037 } 1038#endif 1039 return 0; 1040} 1041 1042static inline int __must_check 1043bpf_jit_binary_lock_ro(struct bpf_binary_header *hdr) 1044{ 1045 set_vm_flush_reset_perms(hdr); 1046 return set_memory_rox((unsigned long)hdr, hdr->size >> PAGE_SHIFT); 1047} 1048 1049int sk_filter_trim_cap(struct sock *sk, struct sk_buff *skb, unsigned int cap); 1050static inline int sk_filter(struct sock *sk, struct sk_buff *skb) 1051{ 1052 return sk_filter_trim_cap(sk, skb, 1); 1053} 1054 1055struct bpf_prog *bpf_prog_select_runtime(struct bpf_prog *fp, int *err); 1056void bpf_prog_free(struct bpf_prog *fp); 1057 1058bool bpf_opcode_in_insntable(u8 code); 1059 1060void bpf_prog_fill_jited_linfo(struct bpf_prog *prog, 1061 const u32 *insn_to_jit_off); 1062int bpf_prog_alloc_jited_linfo(struct bpf_prog *prog); 1063void bpf_prog_jit_attempt_done(struct bpf_prog *prog); 1064 1065struct bpf_prog *bpf_prog_alloc(unsigned int size, gfp_t gfp_extra_flags); 1066struct bpf_prog *bpf_prog_alloc_no_stats(unsigned int size, gfp_t gfp_extra_flags); 1067struct bpf_prog *bpf_prog_realloc(struct bpf_prog *fp_old, unsigned int size, 1068 gfp_t gfp_extra_flags); 1069void __bpf_prog_free(struct bpf_prog *fp); 1070 1071static inline void bpf_prog_unlock_free(struct bpf_prog *fp) 1072{ 1073 __bpf_prog_free(fp); 1074} 1075 1076typedef int (*bpf_aux_classic_check_t)(struct sock_filter *filter, 1077 unsigned int flen); 1078 1079int bpf_prog_create(struct bpf_prog **pfp, struct sock_fprog_kern *fprog); 1080int bpf_prog_create_from_user(struct bpf_prog **pfp, struct sock_fprog *fprog, 1081 bpf_aux_classic_check_t trans, bool save_orig); 1082void bpf_prog_destroy(struct bpf_prog *fp); 1083 1084int sk_attach_filter(struct sock_fprog *fprog, struct sock *sk); 1085int sk_attach_bpf(u32 ufd, struct sock *sk); 1086int sk_reuseport_attach_filter(struct sock_fprog *fprog, struct sock *sk); 1087int sk_reuseport_attach_bpf(u32 ufd, struct sock *sk); 1088void sk_reuseport_prog_free(struct bpf_prog *prog); 1089int sk_detach_filter(struct sock *sk); 1090int sk_get_filter(struct sock *sk, sockptr_t optval, unsigned int len); 1091 1092bool sk_filter_charge(struct sock *sk, struct sk_filter *fp); 1093void sk_filter_uncharge(struct sock *sk, struct sk_filter *fp); 1094 1095u64 __bpf_call_base(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5); 1096#define __bpf_call_base_args \ 1097 ((u64 (*)(u64, u64, u64, u64, u64, const struct bpf_insn *)) \ 1098 (void *)__bpf_call_base) 1099 1100struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog); 1101void bpf_jit_compile(struct bpf_prog *prog); 1102bool bpf_jit_needs_zext(void); 1103bool bpf_jit_inlines_helper_call(s32 imm); 1104bool bpf_jit_supports_subprog_tailcalls(void); 1105bool bpf_jit_supports_percpu_insn(void); 1106bool bpf_jit_supports_kfunc_call(void); 1107bool bpf_jit_supports_far_kfunc_call(void); 1108bool bpf_jit_supports_exceptions(void); 1109bool bpf_jit_supports_ptr_xchg(void); 1110bool bpf_jit_supports_arena(void); 1111bool bpf_jit_supports_insn(struct bpf_insn *insn, bool in_arena); 1112u64 bpf_arch_uaddress_limit(void); 1113void arch_bpf_stack_walk(bool (*consume_fn)(void *cookie, u64 ip, u64 sp, u64 bp), void *cookie); 1114bool bpf_helper_changes_pkt_data(void *func); 1115 1116static inline bool bpf_dump_raw_ok(const struct cred *cred) 1117{ 1118 /* Reconstruction of call-sites is dependent on kallsyms, 1119 * thus make dump the same restriction. 1120 */ 1121 return kallsyms_show_value(cred); 1122} 1123 1124struct bpf_prog *bpf_patch_insn_single(struct bpf_prog *prog, u32 off, 1125 const struct bpf_insn *patch, u32 len); 1126int bpf_remove_insns(struct bpf_prog *prog, u32 off, u32 cnt); 1127 1128static inline bool xdp_return_frame_no_direct(void) 1129{ 1130 struct bpf_redirect_info *ri = bpf_net_ctx_get_ri(); 1131 1132 return ri->kern_flags & BPF_RI_F_RF_NO_DIRECT; 1133} 1134 1135static inline void xdp_set_return_frame_no_direct(void) 1136{ 1137 struct bpf_redirect_info *ri = bpf_net_ctx_get_ri(); 1138 1139 ri->kern_flags |= BPF_RI_F_RF_NO_DIRECT; 1140} 1141 1142static inline void xdp_clear_return_frame_no_direct(void) 1143{ 1144 struct bpf_redirect_info *ri = bpf_net_ctx_get_ri(); 1145 1146 ri->kern_flags &= ~BPF_RI_F_RF_NO_DIRECT; 1147} 1148 1149static inline int xdp_ok_fwd_dev(const struct net_device *fwd, 1150 unsigned int pktlen) 1151{ 1152 unsigned int len; 1153 1154 if (unlikely(!(fwd->flags & IFF_UP))) 1155 return -ENETDOWN; 1156 1157 len = fwd->mtu + fwd->hard_header_len + VLAN_HLEN; 1158 if (pktlen > len) 1159 return -EMSGSIZE; 1160 1161 return 0; 1162} 1163 1164/* The pair of xdp_do_redirect and xdp_do_flush MUST be called in the 1165 * same cpu context. Further for best results no more than a single map 1166 * for the do_redirect/do_flush pair should be used. This limitation is 1167 * because we only track one map and force a flush when the map changes. 1168 * This does not appear to be a real limitation for existing software. 1169 */ 1170int xdp_do_generic_redirect(struct net_device *dev, struct sk_buff *skb, 1171 struct xdp_buff *xdp, struct bpf_prog *prog); 1172int xdp_do_redirect(struct net_device *dev, 1173 struct xdp_buff *xdp, 1174 struct bpf_prog *prog); 1175int xdp_do_redirect_frame(struct net_device *dev, 1176 struct xdp_buff *xdp, 1177 struct xdp_frame *xdpf, 1178 struct bpf_prog *prog); 1179void xdp_do_flush(void); 1180 1181void bpf_warn_invalid_xdp_action(struct net_device *dev, struct bpf_prog *prog, u32 act); 1182 1183#ifdef CONFIG_INET 1184struct sock *bpf_run_sk_reuseport(struct sock_reuseport *reuse, struct sock *sk, 1185 struct bpf_prog *prog, struct sk_buff *skb, 1186 struct sock *migrating_sk, 1187 u32 hash); 1188#else 1189static inline struct sock * 1190bpf_run_sk_reuseport(struct sock_reuseport *reuse, struct sock *sk, 1191 struct bpf_prog *prog, struct sk_buff *skb, 1192 struct sock *migrating_sk, 1193 u32 hash) 1194{ 1195 return NULL; 1196} 1197#endif 1198 1199#ifdef CONFIG_BPF_JIT 1200extern int bpf_jit_enable; 1201extern int bpf_jit_harden; 1202extern int bpf_jit_kallsyms; 1203extern long bpf_jit_limit; 1204extern long bpf_jit_limit_max; 1205 1206typedef void (*bpf_jit_fill_hole_t)(void *area, unsigned int size); 1207 1208void bpf_jit_fill_hole_with_zero(void *area, unsigned int size); 1209 1210struct bpf_binary_header * 1211bpf_jit_binary_alloc(unsigned int proglen, u8 **image_ptr, 1212 unsigned int alignment, 1213 bpf_jit_fill_hole_t bpf_fill_ill_insns); 1214void bpf_jit_binary_free(struct bpf_binary_header *hdr); 1215u64 bpf_jit_alloc_exec_limit(void); 1216void *bpf_jit_alloc_exec(unsigned long size); 1217void bpf_jit_free_exec(void *addr); 1218void bpf_jit_free(struct bpf_prog *fp); 1219struct bpf_binary_header * 1220bpf_jit_binary_pack_hdr(const struct bpf_prog *fp); 1221 1222void *bpf_prog_pack_alloc(u32 size, bpf_jit_fill_hole_t bpf_fill_ill_insns); 1223void bpf_prog_pack_free(void *ptr, u32 size); 1224 1225static inline bool bpf_prog_kallsyms_verify_off(const struct bpf_prog *fp) 1226{ 1227 return list_empty(&fp->aux->ksym.lnode) || 1228 fp->aux->ksym.lnode.prev == LIST_POISON2; 1229} 1230 1231struct bpf_binary_header * 1232bpf_jit_binary_pack_alloc(unsigned int proglen, u8 **ro_image, 1233 unsigned int alignment, 1234 struct bpf_binary_header **rw_hdr, 1235 u8 **rw_image, 1236 bpf_jit_fill_hole_t bpf_fill_ill_insns); 1237int bpf_jit_binary_pack_finalize(struct bpf_binary_header *ro_header, 1238 struct bpf_binary_header *rw_header); 1239void bpf_jit_binary_pack_free(struct bpf_binary_header *ro_header, 1240 struct bpf_binary_header *rw_header); 1241 1242int bpf_jit_add_poke_descriptor(struct bpf_prog *prog, 1243 struct bpf_jit_poke_descriptor *poke); 1244 1245int bpf_jit_get_func_addr(const struct bpf_prog *prog, 1246 const struct bpf_insn *insn, bool extra_pass, 1247 u64 *func_addr, bool *func_addr_fixed); 1248 1249struct bpf_prog *bpf_jit_blind_constants(struct bpf_prog *fp); 1250void bpf_jit_prog_release_other(struct bpf_prog *fp, struct bpf_prog *fp_other); 1251 1252static inline void bpf_jit_dump(unsigned int flen, unsigned int proglen, 1253 u32 pass, void *image) 1254{ 1255 pr_err("flen=%u proglen=%u pass=%u image=%pK from=%s pid=%d\n", flen, 1256 proglen, pass, image, current->comm, task_pid_nr(current)); 1257 1258 if (image) 1259 print_hex_dump(KERN_ERR, "JIT code: ", DUMP_PREFIX_OFFSET, 1260 16, 1, image, proglen, false); 1261} 1262 1263static inline bool bpf_jit_is_ebpf(void) 1264{ 1265# ifdef CONFIG_HAVE_EBPF_JIT 1266 return true; 1267# else 1268 return false; 1269# endif 1270} 1271 1272static inline bool ebpf_jit_enabled(void) 1273{ 1274 return bpf_jit_enable && bpf_jit_is_ebpf(); 1275} 1276 1277static inline bool bpf_prog_ebpf_jited(const struct bpf_prog *fp) 1278{ 1279 return fp->jited && bpf_jit_is_ebpf(); 1280} 1281 1282static inline bool bpf_jit_blinding_enabled(struct bpf_prog *prog) 1283{ 1284 /* These are the prerequisites, should someone ever have the 1285 * idea to call blinding outside of them, we make sure to 1286 * bail out. 1287 */ 1288 if (!bpf_jit_is_ebpf()) 1289 return false; 1290 if (!prog->jit_requested) 1291 return false; 1292 if (!bpf_jit_harden) 1293 return false; 1294 if (bpf_jit_harden == 1 && bpf_token_capable(prog->aux->token, CAP_BPF)) 1295 return false; 1296 1297 return true; 1298} 1299 1300static inline bool bpf_jit_kallsyms_enabled(void) 1301{ 1302 /* There are a couple of corner cases where kallsyms should 1303 * not be enabled f.e. on hardening. 1304 */ 1305 if (bpf_jit_harden) 1306 return false; 1307 if (!bpf_jit_kallsyms) 1308 return false; 1309 if (bpf_jit_kallsyms == 1) 1310 return true; 1311 1312 return false; 1313} 1314 1315int __bpf_address_lookup(unsigned long addr, unsigned long *size, 1316 unsigned long *off, char *sym); 1317bool is_bpf_text_address(unsigned long addr); 1318int bpf_get_kallsym(unsigned int symnum, unsigned long *value, char *type, 1319 char *sym); 1320struct bpf_prog *bpf_prog_ksym_find(unsigned long addr); 1321 1322static inline int 1323bpf_address_lookup(unsigned long addr, unsigned long *size, 1324 unsigned long *off, char **modname, char *sym) 1325{ 1326 int ret = __bpf_address_lookup(addr, size, off, sym); 1327 1328 if (ret && modname) 1329 *modname = NULL; 1330 return ret; 1331} 1332 1333void bpf_prog_kallsyms_add(struct bpf_prog *fp); 1334void bpf_prog_kallsyms_del(struct bpf_prog *fp); 1335 1336#else /* CONFIG_BPF_JIT */ 1337 1338static inline bool ebpf_jit_enabled(void) 1339{ 1340 return false; 1341} 1342 1343static inline bool bpf_jit_blinding_enabled(struct bpf_prog *prog) 1344{ 1345 return false; 1346} 1347 1348static inline bool bpf_prog_ebpf_jited(const struct bpf_prog *fp) 1349{ 1350 return false; 1351} 1352 1353static inline int 1354bpf_jit_add_poke_descriptor(struct bpf_prog *prog, 1355 struct bpf_jit_poke_descriptor *poke) 1356{ 1357 return -ENOTSUPP; 1358} 1359 1360static inline void bpf_jit_free(struct bpf_prog *fp) 1361{ 1362 bpf_prog_unlock_free(fp); 1363} 1364 1365static inline bool bpf_jit_kallsyms_enabled(void) 1366{ 1367 return false; 1368} 1369 1370static inline int 1371__bpf_address_lookup(unsigned long addr, unsigned long *size, 1372 unsigned long *off, char *sym) 1373{ 1374 return 0; 1375} 1376 1377static inline bool is_bpf_text_address(unsigned long addr) 1378{ 1379 return false; 1380} 1381 1382static inline int bpf_get_kallsym(unsigned int symnum, unsigned long *value, 1383 char *type, char *sym) 1384{ 1385 return -ERANGE; 1386} 1387 1388static inline struct bpf_prog *bpf_prog_ksym_find(unsigned long addr) 1389{ 1390 return NULL; 1391} 1392 1393static inline int 1394bpf_address_lookup(unsigned long addr, unsigned long *size, 1395 unsigned long *off, char **modname, char *sym) 1396{ 1397 return 0; 1398} 1399 1400static inline void bpf_prog_kallsyms_add(struct bpf_prog *fp) 1401{ 1402} 1403 1404static inline void bpf_prog_kallsyms_del(struct bpf_prog *fp) 1405{ 1406} 1407 1408#endif /* CONFIG_BPF_JIT */ 1409 1410void bpf_prog_kallsyms_del_all(struct bpf_prog *fp); 1411 1412#define BPF_ANC BIT(15) 1413 1414static inline bool bpf_needs_clear_a(const struct sock_filter *first) 1415{ 1416 switch (first->code) { 1417 case BPF_RET | BPF_K: 1418 case BPF_LD | BPF_W | BPF_LEN: 1419 return false; 1420 1421 case BPF_LD | BPF_W | BPF_ABS: 1422 case BPF_LD | BPF_H | BPF_ABS: 1423 case BPF_LD | BPF_B | BPF_ABS: 1424 if (first->k == SKF_AD_OFF + SKF_AD_ALU_XOR_X) 1425 return true; 1426 return false; 1427 1428 default: 1429 return true; 1430 } 1431} 1432 1433static inline u16 bpf_anc_helper(const struct sock_filter *ftest) 1434{ 1435 BUG_ON(ftest->code & BPF_ANC); 1436 1437 switch (ftest->code) { 1438 case BPF_LD | BPF_W | BPF_ABS: 1439 case BPF_LD | BPF_H | BPF_ABS: 1440 case BPF_LD | BPF_B | BPF_ABS: 1441#define BPF_ANCILLARY(CODE) case SKF_AD_OFF + SKF_AD_##CODE: \ 1442 return BPF_ANC | SKF_AD_##CODE 1443 switch (ftest->k) { 1444 BPF_ANCILLARY(PROTOCOL); 1445 BPF_ANCILLARY(PKTTYPE); 1446 BPF_ANCILLARY(IFINDEX); 1447 BPF_ANCILLARY(NLATTR); 1448 BPF_ANCILLARY(NLATTR_NEST); 1449 BPF_ANCILLARY(MARK); 1450 BPF_ANCILLARY(QUEUE); 1451 BPF_ANCILLARY(HATYPE); 1452 BPF_ANCILLARY(RXHASH); 1453 BPF_ANCILLARY(CPU); 1454 BPF_ANCILLARY(ALU_XOR_X); 1455 BPF_ANCILLARY(VLAN_TAG); 1456 BPF_ANCILLARY(VLAN_TAG_PRESENT); 1457 BPF_ANCILLARY(PAY_OFFSET); 1458 BPF_ANCILLARY(RANDOM); 1459 BPF_ANCILLARY(VLAN_TPID); 1460 } 1461 fallthrough; 1462 default: 1463 return ftest->code; 1464 } 1465} 1466 1467void *bpf_internal_load_pointer_neg_helper(const struct sk_buff *skb, 1468 int k, unsigned int size); 1469 1470static inline int bpf_tell_extensions(void) 1471{ 1472 return SKF_AD_MAX; 1473} 1474 1475struct bpf_sock_addr_kern { 1476 struct sock *sk; 1477 struct sockaddr *uaddr; 1478 /* Temporary "register" to make indirect stores to nested structures 1479 * defined above. We need three registers to make such a store, but 1480 * only two (src and dst) are available at convert_ctx_access time 1481 */ 1482 u64 tmp_reg; 1483 void *t_ctx; /* Attach type specific context. */ 1484 u32 uaddrlen; 1485}; 1486 1487struct bpf_sock_ops_kern { 1488 struct sock *sk; 1489 union { 1490 u32 args[4]; 1491 u32 reply; 1492 u32 replylong[4]; 1493 }; 1494 struct sk_buff *syn_skb; 1495 struct sk_buff *skb; 1496 void *skb_data_end; 1497 u8 op; 1498 u8 is_fullsock; 1499 u8 remaining_opt_len; 1500 u64 temp; /* temp and everything after is not 1501 * initialized to 0 before calling 1502 * the BPF program. New fields that 1503 * should be initialized to 0 should 1504 * be inserted before temp. 1505 * temp is scratch storage used by 1506 * sock_ops_convert_ctx_access 1507 * as temporary storage of a register. 1508 */ 1509}; 1510 1511struct bpf_sysctl_kern { 1512 struct ctl_table_header *head; 1513 const struct ctl_table *table; 1514 void *cur_val; 1515 size_t cur_len; 1516 void *new_val; 1517 size_t new_len; 1518 int new_updated; 1519 int write; 1520 loff_t *ppos; 1521 /* Temporary "register" for indirect stores to ppos. */ 1522 u64 tmp_reg; 1523}; 1524 1525#define BPF_SOCKOPT_KERN_BUF_SIZE 32 1526struct bpf_sockopt_buf { 1527 u8 data[BPF_SOCKOPT_KERN_BUF_SIZE]; 1528}; 1529 1530struct bpf_sockopt_kern { 1531 struct sock *sk; 1532 u8 *optval; 1533 u8 *optval_end; 1534 s32 level; 1535 s32 optname; 1536 s32 optlen; 1537 /* for retval in struct bpf_cg_run_ctx */ 1538 struct task_struct *current_task; 1539 /* Temporary "register" for indirect stores to ppos. */ 1540 u64 tmp_reg; 1541}; 1542 1543int copy_bpf_fprog_from_user(struct sock_fprog *dst, sockptr_t src, int len); 1544 1545struct bpf_sk_lookup_kern { 1546 u16 family; 1547 u16 protocol; 1548 __be16 sport; 1549 u16 dport; 1550 struct { 1551 __be32 saddr; 1552 __be32 daddr; 1553 } v4; 1554 struct { 1555 const struct in6_addr *saddr; 1556 const struct in6_addr *daddr; 1557 } v6; 1558 struct sock *selected_sk; 1559 u32 ingress_ifindex; 1560 bool no_reuseport; 1561}; 1562 1563extern struct static_key_false bpf_sk_lookup_enabled; 1564 1565/* Runners for BPF_SK_LOOKUP programs to invoke on socket lookup. 1566 * 1567 * Allowed return values for a BPF SK_LOOKUP program are SK_PASS and 1568 * SK_DROP. Their meaning is as follows: 1569 * 1570 * SK_PASS && ctx.selected_sk != NULL: use selected_sk as lookup result 1571 * SK_PASS && ctx.selected_sk == NULL: continue to htable-based socket lookup 1572 * SK_DROP : terminate lookup with -ECONNREFUSED 1573 * 1574 * This macro aggregates return values and selected sockets from 1575 * multiple BPF programs according to following rules in order: 1576 * 1577 * 1. If any program returned SK_PASS and a non-NULL ctx.selected_sk, 1578 * macro result is SK_PASS and last ctx.selected_sk is used. 1579 * 2. If any program returned SK_DROP return value, 1580 * macro result is SK_DROP. 1581 * 3. Otherwise result is SK_PASS and ctx.selected_sk is NULL. 1582 * 1583 * Caller must ensure that the prog array is non-NULL, and that the 1584 * array as well as the programs it contains remain valid. 1585 */ 1586#define BPF_PROG_SK_LOOKUP_RUN_ARRAY(array, ctx, func) \ 1587 ({ \ 1588 struct bpf_sk_lookup_kern *_ctx = &(ctx); \ 1589 struct bpf_prog_array_item *_item; \ 1590 struct sock *_selected_sk = NULL; \ 1591 bool _no_reuseport = false; \ 1592 struct bpf_prog *_prog; \ 1593 bool _all_pass = true; \ 1594 u32 _ret; \ 1595 \ 1596 migrate_disable(); \ 1597 _item = &(array)->items[0]; \ 1598 while ((_prog = READ_ONCE(_item->prog))) { \ 1599 /* restore most recent selection */ \ 1600 _ctx->selected_sk = _selected_sk; \ 1601 _ctx->no_reuseport = _no_reuseport; \ 1602 \ 1603 _ret = func(_prog, _ctx); \ 1604 if (_ret == SK_PASS && _ctx->selected_sk) { \ 1605 /* remember last non-NULL socket */ \ 1606 _selected_sk = _ctx->selected_sk; \ 1607 _no_reuseport = _ctx->no_reuseport; \ 1608 } else if (_ret == SK_DROP && _all_pass) { \ 1609 _all_pass = false; \ 1610 } \ 1611 _item++; \ 1612 } \ 1613 _ctx->selected_sk = _selected_sk; \ 1614 _ctx->no_reuseport = _no_reuseport; \ 1615 migrate_enable(); \ 1616 _all_pass || _selected_sk ? SK_PASS : SK_DROP; \ 1617 }) 1618 1619static inline bool bpf_sk_lookup_run_v4(struct net *net, int protocol, 1620 const __be32 saddr, const __be16 sport, 1621 const __be32 daddr, const u16 dport, 1622 const int ifindex, struct sock **psk) 1623{ 1624 struct bpf_prog_array *run_array; 1625 struct sock *selected_sk = NULL; 1626 bool no_reuseport = false; 1627 1628 rcu_read_lock(); 1629 run_array = rcu_dereference(net->bpf.run_array[NETNS_BPF_SK_LOOKUP]); 1630 if (run_array) { 1631 struct bpf_sk_lookup_kern ctx = { 1632 .family = AF_INET, 1633 .protocol = protocol, 1634 .v4.saddr = saddr, 1635 .v4.daddr = daddr, 1636 .sport = sport, 1637 .dport = dport, 1638 .ingress_ifindex = ifindex, 1639 }; 1640 u32 act; 1641 1642 act = BPF_PROG_SK_LOOKUP_RUN_ARRAY(run_array, ctx, bpf_prog_run); 1643 if (act == SK_PASS) { 1644 selected_sk = ctx.selected_sk; 1645 no_reuseport = ctx.no_reuseport; 1646 } else { 1647 selected_sk = ERR_PTR(-ECONNREFUSED); 1648 } 1649 } 1650 rcu_read_unlock(); 1651 *psk = selected_sk; 1652 return no_reuseport; 1653} 1654 1655#if IS_ENABLED(CONFIG_IPV6) 1656static inline bool bpf_sk_lookup_run_v6(struct net *net, int protocol, 1657 const struct in6_addr *saddr, 1658 const __be16 sport, 1659 const struct in6_addr *daddr, 1660 const u16 dport, 1661 const int ifindex, struct sock **psk) 1662{ 1663 struct bpf_prog_array *run_array; 1664 struct sock *selected_sk = NULL; 1665 bool no_reuseport = false; 1666 1667 rcu_read_lock(); 1668 run_array = rcu_dereference(net->bpf.run_array[NETNS_BPF_SK_LOOKUP]); 1669 if (run_array) { 1670 struct bpf_sk_lookup_kern ctx = { 1671 .family = AF_INET6, 1672 .protocol = protocol, 1673 .v6.saddr = saddr, 1674 .v6.daddr = daddr, 1675 .sport = sport, 1676 .dport = dport, 1677 .ingress_ifindex = ifindex, 1678 }; 1679 u32 act; 1680 1681 act = BPF_PROG_SK_LOOKUP_RUN_ARRAY(run_array, ctx, bpf_prog_run); 1682 if (act == SK_PASS) { 1683 selected_sk = ctx.selected_sk; 1684 no_reuseport = ctx.no_reuseport; 1685 } else { 1686 selected_sk = ERR_PTR(-ECONNREFUSED); 1687 } 1688 } 1689 rcu_read_unlock(); 1690 *psk = selected_sk; 1691 return no_reuseport; 1692} 1693#endif /* IS_ENABLED(CONFIG_IPV6) */ 1694 1695static __always_inline long __bpf_xdp_redirect_map(struct bpf_map *map, u64 index, 1696 u64 flags, const u64 flag_mask, 1697 void *lookup_elem(struct bpf_map *map, u32 key)) 1698{ 1699 struct bpf_redirect_info *ri = bpf_net_ctx_get_ri(); 1700 const u64 action_mask = XDP_ABORTED | XDP_DROP | XDP_PASS | XDP_TX; 1701 1702 /* Lower bits of the flags are used as return code on lookup failure */ 1703 if (unlikely(flags & ~(action_mask | flag_mask))) 1704 return XDP_ABORTED; 1705 1706 ri->tgt_value = lookup_elem(map, index); 1707 if (unlikely(!ri->tgt_value) && !(flags & BPF_F_BROADCAST)) { 1708 /* If the lookup fails we want to clear out the state in the 1709 * redirect_info struct completely, so that if an eBPF program 1710 * performs multiple lookups, the last one always takes 1711 * precedence. 1712 */ 1713 ri->map_id = INT_MAX; /* Valid map id idr range: [1,INT_MAX[ */ 1714 ri->map_type = BPF_MAP_TYPE_UNSPEC; 1715 return flags & action_mask; 1716 } 1717 1718 ri->tgt_index = index; 1719 ri->map_id = map->id; 1720 ri->map_type = map->map_type; 1721 1722 if (flags & BPF_F_BROADCAST) { 1723 WRITE_ONCE(ri->map, map); 1724 ri->flags = flags; 1725 } else { 1726 WRITE_ONCE(ri->map, NULL); 1727 ri->flags = 0; 1728 } 1729 1730 return XDP_REDIRECT; 1731} 1732 1733#ifdef CONFIG_NET 1734int __bpf_skb_load_bytes(const struct sk_buff *skb, u32 offset, void *to, u32 len); 1735int __bpf_skb_store_bytes(struct sk_buff *skb, u32 offset, const void *from, 1736 u32 len, u64 flags); 1737int __bpf_xdp_load_bytes(struct xdp_buff *xdp, u32 offset, void *buf, u32 len); 1738int __bpf_xdp_store_bytes(struct xdp_buff *xdp, u32 offset, void *buf, u32 len); 1739void *bpf_xdp_pointer(struct xdp_buff *xdp, u32 offset, u32 len); 1740void bpf_xdp_copy_buf(struct xdp_buff *xdp, unsigned long off, 1741 void *buf, unsigned long len, bool flush); 1742#else /* CONFIG_NET */ 1743static inline int __bpf_skb_load_bytes(const struct sk_buff *skb, u32 offset, 1744 void *to, u32 len) 1745{ 1746 return -EOPNOTSUPP; 1747} 1748 1749static inline int __bpf_skb_store_bytes(struct sk_buff *skb, u32 offset, 1750 const void *from, u32 len, u64 flags) 1751{ 1752 return -EOPNOTSUPP; 1753} 1754 1755static inline int __bpf_xdp_load_bytes(struct xdp_buff *xdp, u32 offset, 1756 void *buf, u32 len) 1757{ 1758 return -EOPNOTSUPP; 1759} 1760 1761static inline int __bpf_xdp_store_bytes(struct xdp_buff *xdp, u32 offset, 1762 void *buf, u32 len) 1763{ 1764 return -EOPNOTSUPP; 1765} 1766 1767static inline void *bpf_xdp_pointer(struct xdp_buff *xdp, u32 offset, u32 len) 1768{ 1769 return NULL; 1770} 1771 1772static inline void bpf_xdp_copy_buf(struct xdp_buff *xdp, unsigned long off, void *buf, 1773 unsigned long len, bool flush) 1774{ 1775} 1776#endif /* CONFIG_NET */ 1777 1778#endif /* __LINUX_FILTER_H__ */