1 /* 2 * Linux Socket Filter Data Structures 3 */ 4 #ifndef __LINUX_FILTER_H__ 5 #define __LINUX_FILTER_H__ 6 7 #include <stdarg.h> 8 9 #include <linux/atomic.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/cryptohash.h> 19 20 #include <net/sch_generic.h> 21 22 #ifdef CONFIG_ARCH_HAS_SET_MEMORY 23 #include <asm/set_memory.h> 24 #endif 25 26 #include <uapi/linux/filter.h> 27 #include <uapi/linux/bpf.h> 28 29 struct sk_buff; 30 struct sock; 31 struct seccomp_data; 32 struct bpf_prog_aux; 33 34 /* ArgX, context and stack frame pointer register positions. Note, 35 * Arg1, Arg2, Arg3, etc are used as argument mappings of function 36 * calls in BPF_CALL instruction. 37 */ 38 #define BPF_REG_ARG1 BPF_REG_1 39 #define BPF_REG_ARG2 BPF_REG_2 40 #define BPF_REG_ARG3 BPF_REG_3 41 #define BPF_REG_ARG4 BPF_REG_4 42 #define BPF_REG_ARG5 BPF_REG_5 43 #define BPF_REG_CTX BPF_REG_6 44 #define BPF_REG_FP BPF_REG_10 45 46 /* Additional register mappings for converted user programs. */ 47 #define BPF_REG_A BPF_REG_0 48 #define BPF_REG_X BPF_REG_7 49 #define BPF_REG_TMP BPF_REG_8 50 51 /* Kernel hidden auxiliary/helper register for hardening step. 52 * Only used by eBPF JITs. It's nothing more than a temporary 53 * register that JITs use internally, only that here it's part 54 * of eBPF instructions that have been rewritten for blinding 55 * constants. See JIT pre-step in bpf_jit_blind_constants(). 56 */ 57 #define BPF_REG_AX MAX_BPF_REG 58 #define MAX_BPF_JIT_REG (MAX_BPF_REG + 1) 59 60 /* As per nm, we expose JITed images as text (code) section for 61 * kallsyms. That way, tools like perf can find it to match 62 * addresses. 63 */ 64 #define BPF_SYM_ELF_TYPE 't' 65 66 /* BPF program can access up to 512 bytes of stack space. */ 67 #define MAX_BPF_STACK 512 68 69 #define BPF_TAG_SIZE 8 70 71 /* Helper macros for filter block array initializers. */ 72 73 /* ALU ops on registers, bpf_add|sub|...: dst_reg += src_reg */ 74 75 #define BPF_ALU64_REG(OP, DST, SRC) \ 76 ((struct bpf_insn) { \ 77 .code = BPF_ALU64 | BPF_OP(OP) | BPF_X, \ 78 .dst_reg = DST, \ 79 .src_reg = SRC, \ 80 .off = 0, \ 81 .imm = 0 }) 82 83 #define BPF_ALU32_REG(OP, DST, SRC) \ 84 ((struct bpf_insn) { \ 85 .code = BPF_ALU | BPF_OP(OP) | BPF_X, \ 86 .dst_reg = DST, \ 87 .src_reg = SRC, \ 88 .off = 0, \ 89 .imm = 0 }) 90 91 /* ALU ops on immediates, bpf_add|sub|...: dst_reg += imm32 */ 92 93 #define BPF_ALU64_IMM(OP, DST, IMM) \ 94 ((struct bpf_insn) { \ 95 .code = BPF_ALU64 | BPF_OP(OP) | BPF_K, \ 96 .dst_reg = DST, \ 97 .src_reg = 0, \ 98 .off = 0, \ 99 .imm = IMM }) 100 101 #define BPF_ALU32_IMM(OP, DST, IMM) \ 102 ((struct bpf_insn) { \ 103 .code = BPF_ALU | BPF_OP(OP) | BPF_K, \ 104 .dst_reg = DST, \ 105 .src_reg = 0, \ 106 .off = 0, \ 107 .imm = IMM }) 108 109 /* Endianess conversion, cpu_to_{l,b}e(), {l,b}e_to_cpu() */ 110 111 #define BPF_ENDIAN(TYPE, DST, LEN) \ 112 ((struct bpf_insn) { \ 113 .code = BPF_ALU | BPF_END | BPF_SRC(TYPE), \ 114 .dst_reg = DST, \ 115 .src_reg = 0, \ 116 .off = 0, \ 117 .imm = LEN }) 118 119 /* Short form of mov, dst_reg = src_reg */ 120 121 #define BPF_MOV64_REG(DST, SRC) \ 122 ((struct bpf_insn) { \ 123 .code = BPF_ALU64 | BPF_MOV | BPF_X, \ 124 .dst_reg = DST, \ 125 .src_reg = SRC, \ 126 .off = 0, \ 127 .imm = 0 }) 128 129 #define BPF_MOV32_REG(DST, SRC) \ 130 ((struct bpf_insn) { \ 131 .code = BPF_ALU | BPF_MOV | BPF_X, \ 132 .dst_reg = DST, \ 133 .src_reg = SRC, \ 134 .off = 0, \ 135 .imm = 0 }) 136 137 /* Short form of mov, dst_reg = imm32 */ 138 139 #define BPF_MOV64_IMM(DST, IMM) \ 140 ((struct bpf_insn) { \ 141 .code = BPF_ALU64 | BPF_MOV | BPF_K, \ 142 .dst_reg = DST, \ 143 .src_reg = 0, \ 144 .off = 0, \ 145 .imm = IMM }) 146 147 #define BPF_MOV32_IMM(DST, IMM) \ 148 ((struct bpf_insn) { \ 149 .code = BPF_ALU | BPF_MOV | BPF_K, \ 150 .dst_reg = DST, \ 151 .src_reg = 0, \ 152 .off = 0, \ 153 .imm = IMM }) 154 155 /* BPF_LD_IMM64 macro encodes single 'load 64-bit immediate' insn */ 156 #define BPF_LD_IMM64(DST, IMM) \ 157 BPF_LD_IMM64_RAW(DST, 0, IMM) 158 159 #define BPF_LD_IMM64_RAW(DST, SRC, IMM) \ 160 ((struct bpf_insn) { \ 161 .code = BPF_LD | BPF_DW | BPF_IMM, \ 162 .dst_reg = DST, \ 163 .src_reg = SRC, \ 164 .off = 0, \ 165 .imm = (__u32) (IMM) }), \ 166 ((struct bpf_insn) { \ 167 .code = 0, /* zero is reserved opcode */ \ 168 .dst_reg = 0, \ 169 .src_reg = 0, \ 170 .off = 0, \ 171 .imm = ((__u64) (IMM)) >> 32 }) 172 173 /* pseudo BPF_LD_IMM64 insn used to refer to process-local map_fd */ 174 #define BPF_LD_MAP_FD(DST, MAP_FD) \ 175 BPF_LD_IMM64_RAW(DST, BPF_PSEUDO_MAP_FD, MAP_FD) 176 177 /* Short form of mov based on type, BPF_X: dst_reg = src_reg, BPF_K: dst_reg = imm32 */ 178 179 #define BPF_MOV64_RAW(TYPE, DST, SRC, IMM) \ 180 ((struct bpf_insn) { \ 181 .code = BPF_ALU64 | BPF_MOV | BPF_SRC(TYPE), \ 182 .dst_reg = DST, \ 183 .src_reg = SRC, \ 184 .off = 0, \ 185 .imm = IMM }) 186 187 #define BPF_MOV32_RAW(TYPE, DST, SRC, IMM) \ 188 ((struct bpf_insn) { \ 189 .code = BPF_ALU | BPF_MOV | BPF_SRC(TYPE), \ 190 .dst_reg = DST, \ 191 .src_reg = SRC, \ 192 .off = 0, \ 193 .imm = IMM }) 194 195 /* Direct packet access, R0 = *(uint *) (skb->data + imm32) */ 196 197 #define BPF_LD_ABS(SIZE, IMM) \ 198 ((struct bpf_insn) { \ 199 .code = BPF_LD | BPF_SIZE(SIZE) | BPF_ABS, \ 200 .dst_reg = 0, \ 201 .src_reg = 0, \ 202 .off = 0, \ 203 .imm = IMM }) 204 205 /* Indirect packet access, R0 = *(uint *) (skb->data + src_reg + imm32) */ 206 207 #define BPF_LD_IND(SIZE, SRC, IMM) \ 208 ((struct bpf_insn) { \ 209 .code = BPF_LD | BPF_SIZE(SIZE) | BPF_IND, \ 210 .dst_reg = 0, \ 211 .src_reg = SRC, \ 212 .off = 0, \ 213 .imm = IMM }) 214 215 /* Memory load, dst_reg = *(uint *) (src_reg + off16) */ 216 217 #define BPF_LDX_MEM(SIZE, DST, SRC, OFF) \ 218 ((struct bpf_insn) { \ 219 .code = BPF_LDX | BPF_SIZE(SIZE) | BPF_MEM, \ 220 .dst_reg = DST, \ 221 .src_reg = SRC, \ 222 .off = OFF, \ 223 .imm = 0 }) 224 225 /* Memory store, *(uint *) (dst_reg + off16) = src_reg */ 226 227 #define BPF_STX_MEM(SIZE, DST, SRC, OFF) \ 228 ((struct bpf_insn) { \ 229 .code = BPF_STX | BPF_SIZE(SIZE) | BPF_MEM, \ 230 .dst_reg = DST, \ 231 .src_reg = SRC, \ 232 .off = OFF, \ 233 .imm = 0 }) 234 235 /* Atomic memory add, *(uint *)(dst_reg + off16) += src_reg */ 236 237 #define BPF_STX_XADD(SIZE, DST, SRC, OFF) \ 238 ((struct bpf_insn) { \ 239 .code = BPF_STX | BPF_SIZE(SIZE) | BPF_XADD, \ 240 .dst_reg = DST, \ 241 .src_reg = SRC, \ 242 .off = OFF, \ 243 .imm = 0 }) 244 245 /* Memory store, *(uint *) (dst_reg + off16) = imm32 */ 246 247 #define BPF_ST_MEM(SIZE, DST, OFF, IMM) \ 248 ((struct bpf_insn) { \ 249 .code = BPF_ST | BPF_SIZE(SIZE) | BPF_MEM, \ 250 .dst_reg = DST, \ 251 .src_reg = 0, \ 252 .off = OFF, \ 253 .imm = IMM }) 254 255 /* Conditional jumps against registers, if (dst_reg 'op' src_reg) goto pc + off16 */ 256 257 #define BPF_JMP_REG(OP, DST, SRC, OFF) \ 258 ((struct bpf_insn) { \ 259 .code = BPF_JMP | BPF_OP(OP) | BPF_X, \ 260 .dst_reg = DST, \ 261 .src_reg = SRC, \ 262 .off = OFF, \ 263 .imm = 0 }) 264 265 /* Conditional jumps against immediates, if (dst_reg 'op' imm32) goto pc + off16 */ 266 267 #define BPF_JMP_IMM(OP, DST, IMM, OFF) \ 268 ((struct bpf_insn) { \ 269 .code = BPF_JMP | BPF_OP(OP) | BPF_K, \ 270 .dst_reg = DST, \ 271 .src_reg = 0, \ 272 .off = OFF, \ 273 .imm = IMM }) 274 275 /* Function call */ 276 277 #define BPF_EMIT_CALL(FUNC) \ 278 ((struct bpf_insn) { \ 279 .code = BPF_JMP | BPF_CALL, \ 280 .dst_reg = 0, \ 281 .src_reg = 0, \ 282 .off = 0, \ 283 .imm = ((FUNC) - __bpf_call_base) }) 284 285 /* Raw code statement block */ 286 287 #define BPF_RAW_INSN(CODE, DST, SRC, OFF, IMM) \ 288 ((struct bpf_insn) { \ 289 .code = CODE, \ 290 .dst_reg = DST, \ 291 .src_reg = SRC, \ 292 .off = OFF, \ 293 .imm = IMM }) 294 295 /* Program exit */ 296 297 #define BPF_EXIT_INSN() \ 298 ((struct bpf_insn) { \ 299 .code = BPF_JMP | BPF_EXIT, \ 300 .dst_reg = 0, \ 301 .src_reg = 0, \ 302 .off = 0, \ 303 .imm = 0 }) 304 305 /* Internal classic blocks for direct assignment */ 306 307 #define __BPF_STMT(CODE, K) \ 308 ((struct sock_filter) BPF_STMT(CODE, K)) 309 310 #define __BPF_JUMP(CODE, K, JT, JF) \ 311 ((struct sock_filter) BPF_JUMP(CODE, K, JT, JF)) 312 313 #define bytes_to_bpf_size(bytes) \ 314 ({ \ 315 int bpf_size = -EINVAL; \ 316 \ 317 if (bytes == sizeof(u8)) \ 318 bpf_size = BPF_B; \ 319 else if (bytes == sizeof(u16)) \ 320 bpf_size = BPF_H; \ 321 else if (bytes == sizeof(u32)) \ 322 bpf_size = BPF_W; \ 323 else if (bytes == sizeof(u64)) \ 324 bpf_size = BPF_DW; \ 325 \ 326 bpf_size; \ 327 }) 328 329 #define BPF_SIZEOF(type) \ 330 ({ \ 331 const int __size = bytes_to_bpf_size(sizeof(type)); \ 332 BUILD_BUG_ON(__size < 0); \ 333 __size; \ 334 }) 335 336 #define BPF_FIELD_SIZEOF(type, field) \ 337 ({ \ 338 const int __size = bytes_to_bpf_size(FIELD_SIZEOF(type, field)); \ 339 BUILD_BUG_ON(__size < 0); \ 340 __size; \ 341 }) 342 343 #define __BPF_MAP_0(m, v, ...) v 344 #define __BPF_MAP_1(m, v, t, a, ...) m(t, a) 345 #define __BPF_MAP_2(m, v, t, a, ...) m(t, a), __BPF_MAP_1(m, v, __VA_ARGS__) 346 #define __BPF_MAP_3(m, v, t, a, ...) m(t, a), __BPF_MAP_2(m, v, __VA_ARGS__) 347 #define __BPF_MAP_4(m, v, t, a, ...) m(t, a), __BPF_MAP_3(m, v, __VA_ARGS__) 348 #define __BPF_MAP_5(m, v, t, a, ...) m(t, a), __BPF_MAP_4(m, v, __VA_ARGS__) 349 350 #define __BPF_REG_0(...) __BPF_PAD(5) 351 #define __BPF_REG_1(...) __BPF_MAP(1, __VA_ARGS__), __BPF_PAD(4) 352 #define __BPF_REG_2(...) __BPF_MAP(2, __VA_ARGS__), __BPF_PAD(3) 353 #define __BPF_REG_3(...) __BPF_MAP(3, __VA_ARGS__), __BPF_PAD(2) 354 #define __BPF_REG_4(...) __BPF_MAP(4, __VA_ARGS__), __BPF_PAD(1) 355 #define __BPF_REG_5(...) __BPF_MAP(5, __VA_ARGS__) 356 357 #define __BPF_MAP(n, ...) __BPF_MAP_##n(__VA_ARGS__) 358 #define __BPF_REG(n, ...) __BPF_REG_##n(__VA_ARGS__) 359 360 #define __BPF_CAST(t, a) \ 361 (__force t) \ 362 (__force \ 363 typeof(__builtin_choose_expr(sizeof(t) == sizeof(unsigned long), \ 364 (unsigned long)0, (t)0))) a 365 #define __BPF_V void 366 #define __BPF_N 367 368 #define __BPF_DECL_ARGS(t, a) t a 369 #define __BPF_DECL_REGS(t, a) u64 a 370 371 #define __BPF_PAD(n) \ 372 __BPF_MAP(n, __BPF_DECL_ARGS, __BPF_N, u64, __ur_1, u64, __ur_2, \ 373 u64, __ur_3, u64, __ur_4, u64, __ur_5) 374 375 #define BPF_CALL_x(x, name, ...) \ 376 static __always_inline \ 377 u64 ____##name(__BPF_MAP(x, __BPF_DECL_ARGS, __BPF_V, __VA_ARGS__)); \ 378 u64 name(__BPF_REG(x, __BPF_DECL_REGS, __BPF_N, __VA_ARGS__)); \ 379 u64 name(__BPF_REG(x, __BPF_DECL_REGS, __BPF_N, __VA_ARGS__)) \ 380 { \ 381 return ____##name(__BPF_MAP(x,__BPF_CAST,__BPF_N,__VA_ARGS__));\ 382 } \ 383 static __always_inline \ 384 u64 ____##name(__BPF_MAP(x, __BPF_DECL_ARGS, __BPF_V, __VA_ARGS__)) 385 386 #define BPF_CALL_0(name, ...) BPF_CALL_x(0, name, __VA_ARGS__) 387 #define BPF_CALL_1(name, ...) BPF_CALL_x(1, name, __VA_ARGS__) 388 #define BPF_CALL_2(name, ...) BPF_CALL_x(2, name, __VA_ARGS__) 389 #define BPF_CALL_3(name, ...) BPF_CALL_x(3, name, __VA_ARGS__) 390 #define BPF_CALL_4(name, ...) BPF_CALL_x(4, name, __VA_ARGS__) 391 #define BPF_CALL_5(name, ...) BPF_CALL_x(5, name, __VA_ARGS__) 392 393 #ifdef CONFIG_COMPAT 394 /* A struct sock_filter is architecture independent. */ 395 struct compat_sock_fprog { 396 u16 len; 397 compat_uptr_t filter; /* struct sock_filter * */ 398 }; 399 #endif 400 401 struct sock_fprog_kern { 402 u16 len; 403 struct sock_filter *filter; 404 }; 405 406 struct bpf_binary_header { 407 unsigned int pages; 408 u8 image[]; 409 }; 410 411 struct bpf_prog { 412 u16 pages; /* Number of allocated pages */ 413 kmemcheck_bitfield_begin(meta); 414 u16 jited:1, /* Is our filter JIT'ed? */ 415 locked:1, /* Program image locked? */ 416 gpl_compatible:1, /* Is filter GPL compatible? */ 417 cb_access:1, /* Is control block accessed? */ 418 dst_needed:1; /* Do we need dst entry? */ 419 kmemcheck_bitfield_end(meta); 420 enum bpf_prog_type type; /* Type of BPF program */ 421 u32 len; /* Number of filter blocks */ 422 u8 tag[BPF_TAG_SIZE]; 423 struct bpf_prog_aux *aux; /* Auxiliary fields */ 424 struct sock_fprog_kern *orig_prog; /* Original BPF program */ 425 unsigned int (*bpf_func)(const void *ctx, 426 const struct bpf_insn *insn); 427 /* Instructions for interpreter */ 428 union { 429 struct sock_filter insns[0]; 430 struct bpf_insn insnsi[0]; 431 }; 432 }; 433 434 struct sk_filter { 435 refcount_t refcnt; 436 struct rcu_head rcu; 437 struct bpf_prog *prog; 438 }; 439 440 #define BPF_PROG_RUN(filter, ctx) (*filter->bpf_func)(ctx, filter->insnsi) 441 442 #define BPF_SKB_CB_LEN QDISC_CB_PRIV_LEN 443 444 struct bpf_skb_data_end { 445 struct qdisc_skb_cb qdisc_cb; 446 void *data_end; 447 }; 448 449 struct xdp_buff { 450 void *data; 451 void *data_end; 452 void *data_hard_start; 453 }; 454 455 /* compute the linear packet data range [data, data_end) which 456 * will be accessed by cls_bpf, act_bpf and lwt programs 457 */ 458 static inline void bpf_compute_data_end(struct sk_buff *skb) 459 { 460 struct bpf_skb_data_end *cb = (struct bpf_skb_data_end *)skb->cb; 461 462 BUILD_BUG_ON(sizeof(*cb) > FIELD_SIZEOF(struct sk_buff, cb)); 463 cb->data_end = skb->data + skb_headlen(skb); 464 } 465 466 static inline u8 *bpf_skb_cb(struct sk_buff *skb) 467 { 468 /* eBPF programs may read/write skb->cb[] area to transfer meta 469 * data between tail calls. Since this also needs to work with 470 * tc, that scratch memory is mapped to qdisc_skb_cb's data area. 471 * 472 * In some socket filter cases, the cb unfortunately needs to be 473 * saved/restored so that protocol specific skb->cb[] data won't 474 * be lost. In any case, due to unpriviledged eBPF programs 475 * attached to sockets, we need to clear the bpf_skb_cb() area 476 * to not leak previous contents to user space. 477 */ 478 BUILD_BUG_ON(FIELD_SIZEOF(struct __sk_buff, cb) != BPF_SKB_CB_LEN); 479 BUILD_BUG_ON(FIELD_SIZEOF(struct __sk_buff, cb) != 480 FIELD_SIZEOF(struct qdisc_skb_cb, data)); 481 482 return qdisc_skb_cb(skb)->data; 483 } 484 485 static inline u32 bpf_prog_run_save_cb(const struct bpf_prog *prog, 486 struct sk_buff *skb) 487 { 488 u8 *cb_data = bpf_skb_cb(skb); 489 u8 cb_saved[BPF_SKB_CB_LEN]; 490 u32 res; 491 492 if (unlikely(prog->cb_access)) { 493 memcpy(cb_saved, cb_data, sizeof(cb_saved)); 494 memset(cb_data, 0, sizeof(cb_saved)); 495 } 496 497 res = BPF_PROG_RUN(prog, skb); 498 499 if (unlikely(prog->cb_access)) 500 memcpy(cb_data, cb_saved, sizeof(cb_saved)); 501 502 return res; 503 } 504 505 static inline u32 bpf_prog_run_clear_cb(const struct bpf_prog *prog, 506 struct sk_buff *skb) 507 { 508 u8 *cb_data = bpf_skb_cb(skb); 509 510 if (unlikely(prog->cb_access)) 511 memset(cb_data, 0, BPF_SKB_CB_LEN); 512 513 return BPF_PROG_RUN(prog, skb); 514 } 515 516 static __always_inline u32 bpf_prog_run_xdp(const struct bpf_prog *prog, 517 struct xdp_buff *xdp) 518 { 519 /* Caller needs to hold rcu_read_lock() (!), otherwise program 520 * can be released while still running, or map elements could be 521 * freed early while still having concurrent users. XDP fastpath 522 * already takes rcu_read_lock() when fetching the program, so 523 * it's not necessary here anymore. 524 */ 525 return BPF_PROG_RUN(prog, xdp); 526 } 527 528 static inline u32 bpf_prog_insn_size(const struct bpf_prog *prog) 529 { 530 return prog->len * sizeof(struct bpf_insn); 531 } 532 533 static inline u32 bpf_prog_tag_scratch_size(const struct bpf_prog *prog) 534 { 535 return round_up(bpf_prog_insn_size(prog) + 536 sizeof(__be64) + 1, SHA_MESSAGE_BYTES); 537 } 538 539 static inline unsigned int bpf_prog_size(unsigned int proglen) 540 { 541 return max(sizeof(struct bpf_prog), 542 offsetof(struct bpf_prog, insns[proglen])); 543 } 544 545 static inline bool bpf_prog_was_classic(const struct bpf_prog *prog) 546 { 547 /* When classic BPF programs have been loaded and the arch 548 * does not have a classic BPF JIT (anymore), they have been 549 * converted via bpf_migrate_filter() to eBPF and thus always 550 * have an unspec program type. 551 */ 552 return prog->type == BPF_PROG_TYPE_UNSPEC; 553 } 554 555 #define bpf_classic_proglen(fprog) (fprog->len * sizeof(fprog->filter[0])) 556 557 #ifdef CONFIG_ARCH_HAS_SET_MEMORY 558 static inline void bpf_prog_lock_ro(struct bpf_prog *fp) 559 { 560 fp->locked = 1; 561 WARN_ON_ONCE(set_memory_ro((unsigned long)fp, fp->pages)); 562 } 563 564 static inline void bpf_prog_unlock_ro(struct bpf_prog *fp) 565 { 566 if (fp->locked) { 567 WARN_ON_ONCE(set_memory_rw((unsigned long)fp, fp->pages)); 568 /* In case set_memory_rw() fails, we want to be the first 569 * to crash here instead of some random place later on. 570 */ 571 fp->locked = 0; 572 } 573 } 574 575 static inline void bpf_jit_binary_lock_ro(struct bpf_binary_header *hdr) 576 { 577 WARN_ON_ONCE(set_memory_ro((unsigned long)hdr, hdr->pages)); 578 } 579 580 static inline void bpf_jit_binary_unlock_ro(struct bpf_binary_header *hdr) 581 { 582 WARN_ON_ONCE(set_memory_rw((unsigned long)hdr, hdr->pages)); 583 } 584 #else 585 static inline void bpf_prog_lock_ro(struct bpf_prog *fp) 586 { 587 } 588 589 static inline void bpf_prog_unlock_ro(struct bpf_prog *fp) 590 { 591 } 592 593 static inline void bpf_jit_binary_lock_ro(struct bpf_binary_header *hdr) 594 { 595 } 596 597 static inline void bpf_jit_binary_unlock_ro(struct bpf_binary_header *hdr) 598 { 599 } 600 #endif /* CONFIG_ARCH_HAS_SET_MEMORY */ 601 602 static inline struct bpf_binary_header * 603 bpf_jit_binary_hdr(const struct bpf_prog *fp) 604 { 605 unsigned long real_start = (unsigned long)fp->bpf_func; 606 unsigned long addr = real_start & PAGE_MASK; 607 608 return (void *)addr; 609 } 610 611 int sk_filter_trim_cap(struct sock *sk, struct sk_buff *skb, unsigned int cap); 612 static inline int sk_filter(struct sock *sk, struct sk_buff *skb) 613 { 614 return sk_filter_trim_cap(sk, skb, 1); 615 } 616 617 struct bpf_prog *bpf_prog_select_runtime(struct bpf_prog *fp, int *err); 618 void bpf_prog_free(struct bpf_prog *fp); 619 620 struct bpf_prog *bpf_prog_alloc(unsigned int size, gfp_t gfp_extra_flags); 621 struct bpf_prog *bpf_prog_realloc(struct bpf_prog *fp_old, unsigned int size, 622 gfp_t gfp_extra_flags); 623 void __bpf_prog_free(struct bpf_prog *fp); 624 625 static inline void bpf_prog_unlock_free(struct bpf_prog *fp) 626 { 627 bpf_prog_unlock_ro(fp); 628 __bpf_prog_free(fp); 629 } 630 631 typedef int (*bpf_aux_classic_check_t)(struct sock_filter *filter, 632 unsigned int flen); 633 634 int bpf_prog_create(struct bpf_prog **pfp, struct sock_fprog_kern *fprog); 635 int bpf_prog_create_from_user(struct bpf_prog **pfp, struct sock_fprog *fprog, 636 bpf_aux_classic_check_t trans, bool save_orig); 637 void bpf_prog_destroy(struct bpf_prog *fp); 638 639 int sk_attach_filter(struct sock_fprog *fprog, struct sock *sk); 640 int sk_attach_bpf(u32 ufd, struct sock *sk); 641 int sk_reuseport_attach_filter(struct sock_fprog *fprog, struct sock *sk); 642 int sk_reuseport_attach_bpf(u32 ufd, struct sock *sk); 643 int sk_detach_filter(struct sock *sk); 644 int sk_get_filter(struct sock *sk, struct sock_filter __user *filter, 645 unsigned int len); 646 647 bool sk_filter_charge(struct sock *sk, struct sk_filter *fp); 648 void sk_filter_uncharge(struct sock *sk, struct sk_filter *fp); 649 650 u64 __bpf_call_base(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5); 651 652 struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog); 653 void bpf_jit_compile(struct bpf_prog *prog); 654 bool bpf_helper_changes_pkt_data(void *func); 655 656 struct bpf_prog *bpf_patch_insn_single(struct bpf_prog *prog, u32 off, 657 const struct bpf_insn *patch, u32 len); 658 void bpf_warn_invalid_xdp_action(u32 act); 659 660 #ifdef CONFIG_BPF_JIT 661 extern int bpf_jit_enable; 662 extern int bpf_jit_harden; 663 extern int bpf_jit_kallsyms; 664 665 typedef void (*bpf_jit_fill_hole_t)(void *area, unsigned int size); 666 667 struct bpf_binary_header * 668 bpf_jit_binary_alloc(unsigned int proglen, u8 **image_ptr, 669 unsigned int alignment, 670 bpf_jit_fill_hole_t bpf_fill_ill_insns); 671 void bpf_jit_binary_free(struct bpf_binary_header *hdr); 672 673 void bpf_jit_free(struct bpf_prog *fp); 674 675 struct bpf_prog *bpf_jit_blind_constants(struct bpf_prog *fp); 676 void bpf_jit_prog_release_other(struct bpf_prog *fp, struct bpf_prog *fp_other); 677 678 static inline void bpf_jit_dump(unsigned int flen, unsigned int proglen, 679 u32 pass, void *image) 680 { 681 pr_err("flen=%u proglen=%u pass=%u image=%pK from=%s pid=%d\n", flen, 682 proglen, pass, image, current->comm, task_pid_nr(current)); 683 684 if (image) 685 print_hex_dump(KERN_ERR, "JIT code: ", DUMP_PREFIX_OFFSET, 686 16, 1, image, proglen, false); 687 } 688 689 static inline bool bpf_jit_is_ebpf(void) 690 { 691 # ifdef CONFIG_HAVE_EBPF_JIT 692 return true; 693 # else 694 return false; 695 # endif 696 } 697 698 static inline bool ebpf_jit_enabled(void) 699 { 700 return bpf_jit_enable && bpf_jit_is_ebpf(); 701 } 702 703 static inline bool bpf_prog_ebpf_jited(const struct bpf_prog *fp) 704 { 705 return fp->jited && bpf_jit_is_ebpf(); 706 } 707 708 static inline bool bpf_jit_blinding_enabled(void) 709 { 710 /* These are the prerequisites, should someone ever have the 711 * idea to call blinding outside of them, we make sure to 712 * bail out. 713 */ 714 if (!bpf_jit_is_ebpf()) 715 return false; 716 if (!bpf_jit_enable) 717 return false; 718 if (!bpf_jit_harden) 719 return false; 720 if (bpf_jit_harden == 1 && capable(CAP_SYS_ADMIN)) 721 return false; 722 723 return true; 724 } 725 726 static inline bool bpf_jit_kallsyms_enabled(void) 727 { 728 /* There are a couple of corner cases where kallsyms should 729 * not be enabled f.e. on hardening. 730 */ 731 if (bpf_jit_harden) 732 return false; 733 if (!bpf_jit_kallsyms) 734 return false; 735 if (bpf_jit_kallsyms == 1) 736 return true; 737 738 return false; 739 } 740 741 const char *__bpf_address_lookup(unsigned long addr, unsigned long *size, 742 unsigned long *off, char *sym); 743 bool is_bpf_text_address(unsigned long addr); 744 int bpf_get_kallsym(unsigned int symnum, unsigned long *value, char *type, 745 char *sym); 746 747 static inline const char * 748 bpf_address_lookup(unsigned long addr, unsigned long *size, 749 unsigned long *off, char **modname, char *sym) 750 { 751 const char *ret = __bpf_address_lookup(addr, size, off, sym); 752 753 if (ret && modname) 754 *modname = NULL; 755 return ret; 756 } 757 758 void bpf_prog_kallsyms_add(struct bpf_prog *fp); 759 void bpf_prog_kallsyms_del(struct bpf_prog *fp); 760 761 #else /* CONFIG_BPF_JIT */ 762 763 static inline bool ebpf_jit_enabled(void) 764 { 765 return false; 766 } 767 768 static inline bool bpf_prog_ebpf_jited(const struct bpf_prog *fp) 769 { 770 return false; 771 } 772 773 static inline void bpf_jit_free(struct bpf_prog *fp) 774 { 775 bpf_prog_unlock_free(fp); 776 } 777 778 static inline bool bpf_jit_kallsyms_enabled(void) 779 { 780 return false; 781 } 782 783 static inline const char * 784 __bpf_address_lookup(unsigned long addr, unsigned long *size, 785 unsigned long *off, char *sym) 786 { 787 return NULL; 788 } 789 790 static inline bool is_bpf_text_address(unsigned long addr) 791 { 792 return false; 793 } 794 795 static inline int bpf_get_kallsym(unsigned int symnum, unsigned long *value, 796 char *type, char *sym) 797 { 798 return -ERANGE; 799 } 800 801 static inline const char * 802 bpf_address_lookup(unsigned long addr, unsigned long *size, 803 unsigned long *off, char **modname, char *sym) 804 { 805 return NULL; 806 } 807 808 static inline void bpf_prog_kallsyms_add(struct bpf_prog *fp) 809 { 810 } 811 812 static inline void bpf_prog_kallsyms_del(struct bpf_prog *fp) 813 { 814 } 815 #endif /* CONFIG_BPF_JIT */ 816 817 #define BPF_ANC BIT(15) 818 819 static inline bool bpf_needs_clear_a(const struct sock_filter *first) 820 { 821 switch (first->code) { 822 case BPF_RET | BPF_K: 823 case BPF_LD | BPF_W | BPF_LEN: 824 return false; 825 826 case BPF_LD | BPF_W | BPF_ABS: 827 case BPF_LD | BPF_H | BPF_ABS: 828 case BPF_LD | BPF_B | BPF_ABS: 829 if (first->k == SKF_AD_OFF + SKF_AD_ALU_XOR_X) 830 return true; 831 return false; 832 833 default: 834 return true; 835 } 836 } 837 838 static inline u16 bpf_anc_helper(const struct sock_filter *ftest) 839 { 840 BUG_ON(ftest->code & BPF_ANC); 841 842 switch (ftest->code) { 843 case BPF_LD | BPF_W | BPF_ABS: 844 case BPF_LD | BPF_H | BPF_ABS: 845 case BPF_LD | BPF_B | BPF_ABS: 846 #define BPF_ANCILLARY(CODE) case SKF_AD_OFF + SKF_AD_##CODE: \ 847 return BPF_ANC | SKF_AD_##CODE 848 switch (ftest->k) { 849 BPF_ANCILLARY(PROTOCOL); 850 BPF_ANCILLARY(PKTTYPE); 851 BPF_ANCILLARY(IFINDEX); 852 BPF_ANCILLARY(NLATTR); 853 BPF_ANCILLARY(NLATTR_NEST); 854 BPF_ANCILLARY(MARK); 855 BPF_ANCILLARY(QUEUE); 856 BPF_ANCILLARY(HATYPE); 857 BPF_ANCILLARY(RXHASH); 858 BPF_ANCILLARY(CPU); 859 BPF_ANCILLARY(ALU_XOR_X); 860 BPF_ANCILLARY(VLAN_TAG); 861 BPF_ANCILLARY(VLAN_TAG_PRESENT); 862 BPF_ANCILLARY(PAY_OFFSET); 863 BPF_ANCILLARY(RANDOM); 864 BPF_ANCILLARY(VLAN_TPID); 865 } 866 /* Fallthrough. */ 867 default: 868 return ftest->code; 869 } 870 } 871 872 void *bpf_internal_load_pointer_neg_helper(const struct sk_buff *skb, 873 int k, unsigned int size); 874 875 static inline void *bpf_load_pointer(const struct sk_buff *skb, int k, 876 unsigned int size, void *buffer) 877 { 878 if (k >= 0) 879 return skb_header_pointer(skb, k, size, buffer); 880 881 return bpf_internal_load_pointer_neg_helper(skb, k, size); 882 } 883 884 static inline int bpf_tell_extensions(void) 885 { 886 return SKF_AD_MAX; 887 } 888 889 #endif /* __LINUX_FILTER_H__ */ 890