1 #ifndef __BPF_EXPERIMENTAL__ 2 #define __BPF_EXPERIMENTAL__ 3 4 #include <vmlinux.h> 5 #include <bpf/bpf_tracing.h> 6 #include <bpf/bpf_helpers.h> 7 #include <bpf/bpf_core_read.h> 8 9 #define __contains(name, node) __attribute__((btf_decl_tag("contains:" #name ":" #node))) 10 11 /* Description 12 * Allocates an object of the type represented by 'local_type_id' in 13 * program BTF. User may use the bpf_core_type_id_local macro to pass the 14 * type ID of a struct in program BTF. 15 * 16 * The 'local_type_id' parameter must be a known constant. 17 * The 'meta' parameter is rewritten by the verifier, no need for BPF 18 * program to set it. 19 * Returns 20 * A pointer to an object of the type corresponding to the passed in 21 * 'local_type_id', or NULL on failure. 22 */ 23 extern void *bpf_obj_new_impl(__u64 local_type_id, void *meta) __ksym; 24 25 /* Convenience macro to wrap over bpf_obj_new_impl */ 26 #define bpf_obj_new(type) ((type *)bpf_obj_new_impl(bpf_core_type_id_local(type), NULL)) 27 28 /* Description 29 * Free an allocated object. All fields of the object that require 30 * destruction will be destructed before the storage is freed. 31 * 32 * The 'meta' parameter is rewritten by the verifier, no need for BPF 33 * program to set it. 34 * Returns 35 * Void. 36 */ 37 extern void bpf_obj_drop_impl(void *kptr, void *meta) __ksym; 38 39 /* Convenience macro to wrap over bpf_obj_drop_impl */ 40 #define bpf_obj_drop(kptr) bpf_obj_drop_impl(kptr, NULL) 41 42 /* Description 43 * Increment the refcount on a refcounted local kptr, turning the 44 * non-owning reference input into an owning reference in the process. 45 * 46 * The 'meta' parameter is rewritten by the verifier, no need for BPF 47 * program to set it. 48 * Returns 49 * An owning reference to the object pointed to by 'kptr' 50 */ 51 extern void *bpf_refcount_acquire_impl(void *kptr, void *meta) __ksym; 52 53 /* Convenience macro to wrap over bpf_refcount_acquire_impl */ 54 #define bpf_refcount_acquire(kptr) bpf_refcount_acquire_impl(kptr, NULL) 55 56 /* Description 57 * Add a new entry to the beginning of the BPF linked list. 58 * 59 * The 'meta' and 'off' parameters are rewritten by the verifier, no need 60 * for BPF programs to set them 61 * Returns 62 * 0 if the node was successfully added 63 * -EINVAL if the node wasn't added because it's already in a list 64 */ 65 extern int bpf_list_push_front_impl(struct bpf_list_head *head, 66 struct bpf_list_node *node, 67 void *meta, __u64 off) __ksym; 68 69 /* Convenience macro to wrap over bpf_list_push_front_impl */ 70 #define bpf_list_push_front(head, node) bpf_list_push_front_impl(head, node, NULL, 0) 71 72 /* Description 73 * Add a new entry to the end of the BPF linked list. 74 * 75 * The 'meta' and 'off' parameters are rewritten by the verifier, no need 76 * for BPF programs to set them 77 * Returns 78 * 0 if the node was successfully added 79 * -EINVAL if the node wasn't added because it's already in a list 80 */ 81 extern int bpf_list_push_back_impl(struct bpf_list_head *head, 82 struct bpf_list_node *node, 83 void *meta, __u64 off) __ksym; 84 85 /* Convenience macro to wrap over bpf_list_push_back_impl */ 86 #define bpf_list_push_back(head, node) bpf_list_push_back_impl(head, node, NULL, 0) 87 88 /* Description 89 * Remove the entry at the beginning of the BPF linked list. 90 * Returns 91 * Pointer to bpf_list_node of deleted entry, or NULL if list is empty. 92 */ 93 extern struct bpf_list_node *bpf_list_pop_front(struct bpf_list_head *head) __ksym; 94 95 /* Description 96 * Remove the entry at the end of the BPF linked list. 97 * Returns 98 * Pointer to bpf_list_node of deleted entry, or NULL if list is empty. 99 */ 100 extern struct bpf_list_node *bpf_list_pop_back(struct bpf_list_head *head) __ksym; 101 102 /* Description 103 * Remove 'node' from rbtree with root 'root' 104 * Returns 105 * Pointer to the removed node, or NULL if 'root' didn't contain 'node' 106 */ 107 extern struct bpf_rb_node *bpf_rbtree_remove(struct bpf_rb_root *root, 108 struct bpf_rb_node *node) __ksym; 109 110 /* Description 111 * Add 'node' to rbtree with root 'root' using comparator 'less' 112 * 113 * The 'meta' and 'off' parameters are rewritten by the verifier, no need 114 * for BPF programs to set them 115 * Returns 116 * 0 if the node was successfully added 117 * -EINVAL if the node wasn't added because it's already in a tree 118 */ 119 extern int bpf_rbtree_add_impl(struct bpf_rb_root *root, struct bpf_rb_node *node, 120 bool (less)(struct bpf_rb_node *a, const struct bpf_rb_node *b), 121 void *meta, __u64 off) __ksym; 122 123 /* Convenience macro to wrap over bpf_rbtree_add_impl */ 124 #define bpf_rbtree_add(head, node, less) bpf_rbtree_add_impl(head, node, less, NULL, 0) 125 126 /* Description 127 * Return the first (leftmost) node in input tree 128 * Returns 129 * Pointer to the node, which is _not_ removed from the tree. If the tree 130 * contains no nodes, returns NULL. 131 */ 132 extern struct bpf_rb_node *bpf_rbtree_first(struct bpf_rb_root *root) __ksym; 133 134 /* Description 135 * Allocates a percpu object of the type represented by 'local_type_id' in 136 * program BTF. User may use the bpf_core_type_id_local macro to pass the 137 * type ID of a struct in program BTF. 138 * 139 * The 'local_type_id' parameter must be a known constant. 140 * The 'meta' parameter is rewritten by the verifier, no need for BPF 141 * program to set it. 142 * Returns 143 * A pointer to a percpu object of the type corresponding to the passed in 144 * 'local_type_id', or NULL on failure. 145 */ 146 extern void *bpf_percpu_obj_new_impl(__u64 local_type_id, void *meta) __ksym; 147 148 /* Convenience macro to wrap over bpf_percpu_obj_new_impl */ 149 #define bpf_percpu_obj_new(type) ((type __percpu_kptr *)bpf_percpu_obj_new_impl(bpf_core_type_id_local(type), NULL)) 150 151 /* Description 152 * Free an allocated percpu object. All fields of the object that require 153 * destruction will be destructed before the storage is freed. 154 * 155 * The 'meta' parameter is rewritten by the verifier, no need for BPF 156 * program to set it. 157 * Returns 158 * Void. 159 */ 160 extern void bpf_percpu_obj_drop_impl(void *kptr, void *meta) __ksym; 161 162 struct bpf_iter_task_vma; 163 164 extern int bpf_iter_task_vma_new(struct bpf_iter_task_vma *it, 165 struct task_struct *task, 166 unsigned long addr) __ksym; 167 extern struct vm_area_struct *bpf_iter_task_vma_next(struct bpf_iter_task_vma *it) __ksym; 168 extern void bpf_iter_task_vma_destroy(struct bpf_iter_task_vma *it) __ksym; 169 170 /* Convenience macro to wrap over bpf_obj_drop_impl */ 171 #define bpf_percpu_obj_drop(kptr) bpf_percpu_obj_drop_impl(kptr, NULL) 172 173 /* Description 174 * Throw a BPF exception from the program, immediately terminating its 175 * execution and unwinding the stack. The supplied 'cookie' parameter 176 * will be the return value of the program when an exception is thrown, 177 * and the default exception callback is used. Otherwise, if an exception 178 * callback is set using the '__exception_cb(callback)' declaration tag 179 * on the main program, the 'cookie' parameter will be the callback's only 180 * input argument. 181 * 182 * Thus, in case of default exception callback, 'cookie' is subjected to 183 * constraints on the program's return value (as with R0 on exit). 184 * Otherwise, the return value of the marked exception callback will be 185 * subjected to the same checks. 186 * 187 * Note that throwing an exception with lingering resources (locks, 188 * references, etc.) will lead to a verification error. 189 * 190 * Note that callbacks *cannot* call this helper. 191 * Returns 192 * Never. 193 * Throws 194 * An exception with the specified 'cookie' value. 195 */ 196 extern void bpf_throw(u64 cookie) __ksym; 197 198 /* This macro must be used to mark the exception callback corresponding to the 199 * main program. For example: 200 * 201 * int exception_cb(u64 cookie) { 202 * return cookie; 203 * } 204 * 205 * SEC("tc") 206 * __exception_cb(exception_cb) 207 * int main_prog(struct __sk_buff *ctx) { 208 * ... 209 * return TC_ACT_OK; 210 * } 211 * 212 * Here, exception callback for the main program will be 'exception_cb'. Note 213 * that this attribute can only be used once, and multiple exception callbacks 214 * specified for the main program will lead to verification error. 215 */ 216 #define __exception_cb(name) __attribute__((btf_decl_tag("exception_callback:" #name))) 217 218 #define __bpf_assert_signed(x) _Generic((x), \ 219 unsigned long: 0, \ 220 unsigned long long: 0, \ 221 signed long: 1, \ 222 signed long long: 1 \ 223 ) 224 225 #define __bpf_assert_check(LHS, op, RHS) \ 226 _Static_assert(sizeof(&(LHS)), "1st argument must be an lvalue expression"); \ 227 _Static_assert(sizeof(LHS) == 8, "Only 8-byte integers are supported\n"); \ 228 _Static_assert(__builtin_constant_p(__bpf_assert_signed(LHS)), "internal static assert"); \ 229 _Static_assert(__builtin_constant_p((RHS)), "2nd argument must be a constant expression") 230 231 #define __bpf_assert(LHS, op, cons, RHS, VAL) \ 232 ({ \ 233 (void)bpf_throw; \ 234 asm volatile ("if %[lhs] " op " %[rhs] goto +2; r1 = %[value]; call bpf_throw" \ 235 : : [lhs] "r"(LHS), [rhs] cons(RHS), [value] "ri"(VAL) : ); \ 236 }) 237 238 #define __bpf_assert_op_sign(LHS, op, cons, RHS, VAL, supp_sign) \ 239 ({ \ 240 __bpf_assert_check(LHS, op, RHS); \ 241 if (__bpf_assert_signed(LHS) && !(supp_sign)) \ 242 __bpf_assert(LHS, "s" #op, cons, RHS, VAL); \ 243 else \ 244 __bpf_assert(LHS, #op, cons, RHS, VAL); \ 245 }) 246 247 #define __bpf_assert_op(LHS, op, RHS, VAL, supp_sign) \ 248 ({ \ 249 if (sizeof(typeof(RHS)) == 8) { \ 250 const typeof(RHS) rhs_var = (RHS); \ 251 __bpf_assert_op_sign(LHS, op, "r", rhs_var, VAL, supp_sign); \ 252 } else { \ 253 __bpf_assert_op_sign(LHS, op, "i", RHS, VAL, supp_sign); \ 254 } \ 255 }) 256 257 /* Description 258 * Assert that a conditional expression is true. 259 * Returns 260 * Void. 261 * Throws 262 * An exception with the value zero when the assertion fails. 263 */ 264 #define bpf_assert(cond) if (!(cond)) bpf_throw(0); 265 266 /* Description 267 * Assert that a conditional expression is true. 268 * Returns 269 * Void. 270 * Throws 271 * An exception with the specified value when the assertion fails. 272 */ 273 #define bpf_assert_with(cond, value) if (!(cond)) bpf_throw(value); 274 275 /* Description 276 * Assert that LHS is equal to RHS. This statement updates the known value 277 * of LHS during verification. Note that RHS must be a constant value, and 278 * must fit within the data type of LHS. 279 * Returns 280 * Void. 281 * Throws 282 * An exception with the value zero when the assertion fails. 283 */ 284 #define bpf_assert_eq(LHS, RHS) \ 285 ({ \ 286 barrier_var(LHS); \ 287 __bpf_assert_op(LHS, ==, RHS, 0, true); \ 288 }) 289 290 /* Description 291 * Assert that LHS is equal to RHS. This statement updates the known value 292 * of LHS during verification. Note that RHS must be a constant value, and 293 * must fit within the data type of LHS. 294 * Returns 295 * Void. 296 * Throws 297 * An exception with the specified value when the assertion fails. 298 */ 299 #define bpf_assert_eq_with(LHS, RHS, value) \ 300 ({ \ 301 barrier_var(LHS); \ 302 __bpf_assert_op(LHS, ==, RHS, value, true); \ 303 }) 304 305 /* Description 306 * Assert that LHS is less than RHS. This statement updates the known 307 * bounds of LHS during verification. Note that RHS must be a constant 308 * value, and must fit within the data type of LHS. 309 * Returns 310 * Void. 311 * Throws 312 * An exception with the value zero when the assertion fails. 313 */ 314 #define bpf_assert_lt(LHS, RHS) \ 315 ({ \ 316 barrier_var(LHS); \ 317 __bpf_assert_op(LHS, <, RHS, 0, false); \ 318 }) 319 320 /* Description 321 * Assert that LHS is less than RHS. This statement updates the known 322 * bounds of LHS during verification. Note that RHS must be a constant 323 * value, and must fit within the data type of LHS. 324 * Returns 325 * Void. 326 * Throws 327 * An exception with the specified value when the assertion fails. 328 */ 329 #define bpf_assert_lt_with(LHS, RHS, value) \ 330 ({ \ 331 barrier_var(LHS); \ 332 __bpf_assert_op(LHS, <, RHS, value, false); \ 333 }) 334 335 /* Description 336 * Assert that LHS is greater than RHS. This statement updates the known 337 * bounds of LHS during verification. Note that RHS must be a constant 338 * value, and must fit within the data type of LHS. 339 * Returns 340 * Void. 341 * Throws 342 * An exception with the value zero when the assertion fails. 343 */ 344 #define bpf_assert_gt(LHS, RHS) \ 345 ({ \ 346 barrier_var(LHS); \ 347 __bpf_assert_op(LHS, >, RHS, 0, false); \ 348 }) 349 350 /* Description 351 * Assert that LHS is greater than RHS. This statement updates the known 352 * bounds of LHS during verification. Note that RHS must be a constant 353 * value, and must fit within the data type of LHS. 354 * Returns 355 * Void. 356 * Throws 357 * An exception with the specified value when the assertion fails. 358 */ 359 #define bpf_assert_gt_with(LHS, RHS, value) \ 360 ({ \ 361 barrier_var(LHS); \ 362 __bpf_assert_op(LHS, >, RHS, value, false); \ 363 }) 364 365 /* Description 366 * Assert that LHS is less than or equal to RHS. This statement updates the 367 * known bounds of LHS during verification. Note that RHS must be a 368 * constant value, and must fit within the data type of LHS. 369 * Returns 370 * Void. 371 * Throws 372 * An exception with the value zero when the assertion fails. 373 */ 374 #define bpf_assert_le(LHS, RHS) \ 375 ({ \ 376 barrier_var(LHS); \ 377 __bpf_assert_op(LHS, <=, RHS, 0, false); \ 378 }) 379 380 /* Description 381 * Assert that LHS is less than or equal to RHS. This statement updates the 382 * known bounds of LHS during verification. Note that RHS must be a 383 * constant value, and must fit within the data type of LHS. 384 * Returns 385 * Void. 386 * Throws 387 * An exception with the specified value when the assertion fails. 388 */ 389 #define bpf_assert_le_with(LHS, RHS, value) \ 390 ({ \ 391 barrier_var(LHS); \ 392 __bpf_assert_op(LHS, <=, RHS, value, false); \ 393 }) 394 395 /* Description 396 * Assert that LHS is greater than or equal to RHS. This statement updates 397 * the known bounds of LHS during verification. Note that RHS must be a 398 * constant value, and must fit within the data type of LHS. 399 * Returns 400 * Void. 401 * Throws 402 * An exception with the value zero when the assertion fails. 403 */ 404 #define bpf_assert_ge(LHS, RHS) \ 405 ({ \ 406 barrier_var(LHS); \ 407 __bpf_assert_op(LHS, >=, RHS, 0, false); \ 408 }) 409 410 /* Description 411 * Assert that LHS is greater than or equal to RHS. This statement updates 412 * the known bounds of LHS during verification. Note that RHS must be a 413 * constant value, and must fit within the data type of LHS. 414 * Returns 415 * Void. 416 * Throws 417 * An exception with the specified value when the assertion fails. 418 */ 419 #define bpf_assert_ge_with(LHS, RHS, value) \ 420 ({ \ 421 barrier_var(LHS); \ 422 __bpf_assert_op(LHS, >=, RHS, value, false); \ 423 }) 424 425 /* Description 426 * Assert that LHS is in the range [BEG, END] (inclusive of both). This 427 * statement updates the known bounds of LHS during verification. Note 428 * that both BEG and END must be constant values, and must fit within the 429 * data type of LHS. 430 * Returns 431 * Void. 432 * Throws 433 * An exception with the value zero when the assertion fails. 434 */ 435 #define bpf_assert_range(LHS, BEG, END) \ 436 ({ \ 437 _Static_assert(BEG <= END, "BEG must be <= END"); \ 438 barrier_var(LHS); \ 439 __bpf_assert_op(LHS, >=, BEG, 0, false); \ 440 __bpf_assert_op(LHS, <=, END, 0, false); \ 441 }) 442 443 /* Description 444 * Assert that LHS is in the range [BEG, END] (inclusive of both). This 445 * statement updates the known bounds of LHS during verification. Note 446 * that both BEG and END must be constant values, and must fit within the 447 * data type of LHS. 448 * Returns 449 * Void. 450 * Throws 451 * An exception with the specified value when the assertion fails. 452 */ 453 #define bpf_assert_range_with(LHS, BEG, END, value) \ 454 ({ \ 455 _Static_assert(BEG <= END, "BEG must be <= END"); \ 456 barrier_var(LHS); \ 457 __bpf_assert_op(LHS, >=, BEG, value, false); \ 458 __bpf_assert_op(LHS, <=, END, value, false); \ 459 }) 460 461 struct bpf_iter_css_task; 462 struct cgroup_subsys_state; 463 extern int bpf_iter_css_task_new(struct bpf_iter_css_task *it, 464 struct cgroup_subsys_state *css, unsigned int flags) __weak __ksym; 465 extern struct task_struct *bpf_iter_css_task_next(struct bpf_iter_css_task *it) __weak __ksym; 466 extern void bpf_iter_css_task_destroy(struct bpf_iter_css_task *it) __weak __ksym; 467 468 struct bpf_iter_task; 469 extern int bpf_iter_task_new(struct bpf_iter_task *it, 470 struct task_struct *task, unsigned int flags) __weak __ksym; 471 extern struct task_struct *bpf_iter_task_next(struct bpf_iter_task *it) __weak __ksym; 472 extern void bpf_iter_task_destroy(struct bpf_iter_task *it) __weak __ksym; 473 474 struct bpf_iter_css; 475 extern int bpf_iter_css_new(struct bpf_iter_css *it, 476 struct cgroup_subsys_state *start, unsigned int flags) __weak __ksym; 477 extern struct cgroup_subsys_state *bpf_iter_css_next(struct bpf_iter_css *it) __weak __ksym; 478 extern void bpf_iter_css_destroy(struct bpf_iter_css *it) __weak __ksym; 479 480 #endif 481