1 // SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) 2 /* Copyright (c) 2018 Facebook */ 3 4 #include <ctype.h> 5 #include <stdio.h> /* for (FILE *) used by json_writer */ 6 #include <string.h> 7 #include <unistd.h> 8 #include <asm/byteorder.h> 9 #include <linux/bitops.h> 10 #include <linux/btf.h> 11 #include <linux/err.h> 12 #include <bpf/btf.h> 13 #include <bpf/bpf.h> 14 15 #include "json_writer.h" 16 #include "main.h" 17 18 #define BITS_PER_BYTE_MASK (BITS_PER_BYTE - 1) 19 #define BITS_PER_BYTE_MASKED(bits) ((bits) & BITS_PER_BYTE_MASK) 20 #define BITS_ROUNDDOWN_BYTES(bits) ((bits) >> 3) 21 #define BITS_ROUNDUP_BYTES(bits) \ 22 (BITS_ROUNDDOWN_BYTES(bits) + !!BITS_PER_BYTE_MASKED(bits)) 23 24 static int btf_dumper_do_type(const struct btf_dumper *d, __u32 type_id, 25 __u8 bit_offset, const void *data); 26 27 static int btf_dump_func(const struct btf *btf, char *func_sig, 28 const struct btf_type *func_proto, 29 const struct btf_type *func, int pos, int size); 30 31 static int dump_prog_id_as_func_ptr(const struct btf_dumper *d, 32 const struct btf_type *func_proto, 33 __u32 prog_id) 34 { 35 const struct btf_type *func_type; 36 int prog_fd = -1, func_sig_len; 37 struct bpf_prog_info info = {}; 38 __u32 info_len = sizeof(info); 39 const char *prog_name = NULL; 40 struct btf *prog_btf = NULL; 41 struct bpf_func_info finfo; 42 __u32 finfo_rec_size; 43 char prog_str[1024]; 44 int err; 45 46 /* Get the ptr's func_proto */ 47 func_sig_len = btf_dump_func(d->btf, prog_str, func_proto, NULL, 0, 48 sizeof(prog_str)); 49 if (func_sig_len == -1) 50 return -1; 51 52 if (!prog_id) 53 goto print; 54 55 /* Get the bpf_prog's name. Obtain from func_info. */ 56 prog_fd = bpf_prog_get_fd_by_id(prog_id); 57 if (prog_fd < 0) 58 goto print; 59 60 err = bpf_prog_get_info_by_fd(prog_fd, &info, &info_len); 61 if (err) 62 goto print; 63 64 if (!info.btf_id || !info.nr_func_info) 65 goto print; 66 67 finfo_rec_size = info.func_info_rec_size; 68 memset(&info, 0, sizeof(info)); 69 info.nr_func_info = 1; 70 info.func_info_rec_size = finfo_rec_size; 71 info.func_info = ptr_to_u64(&finfo); 72 73 err = bpf_prog_get_info_by_fd(prog_fd, &info, &info_len); 74 if (err) 75 goto print; 76 77 prog_btf = btf__load_from_kernel_by_id(info.btf_id); 78 if (!prog_btf) 79 goto print; 80 func_type = btf__type_by_id(prog_btf, finfo.type_id); 81 if (!func_type || !btf_is_func(func_type)) 82 goto print; 83 84 prog_name = btf__name_by_offset(prog_btf, func_type->name_off); 85 86 print: 87 if (!prog_id) 88 snprintf(&prog_str[func_sig_len], 89 sizeof(prog_str) - func_sig_len, " 0"); 90 else if (prog_name) 91 snprintf(&prog_str[func_sig_len], 92 sizeof(prog_str) - func_sig_len, 93 " %s/prog_id:%u", prog_name, prog_id); 94 else 95 snprintf(&prog_str[func_sig_len], 96 sizeof(prog_str) - func_sig_len, 97 " <unknown_prog_name>/prog_id:%u", prog_id); 98 99 prog_str[sizeof(prog_str) - 1] = '\0'; 100 jsonw_string(d->jw, prog_str); 101 btf__free(prog_btf); 102 if (prog_fd >= 0) 103 close(prog_fd); 104 return 0; 105 } 106 107 static void btf_dumper_ptr(const struct btf_dumper *d, 108 const struct btf_type *t, 109 const void *data) 110 { 111 unsigned long value = *(unsigned long *)data; 112 const struct btf_type *ptr_type; 113 __s32 ptr_type_id; 114 115 if (!d->prog_id_as_func_ptr || value > UINT32_MAX) 116 goto print_ptr_value; 117 118 ptr_type_id = btf__resolve_type(d->btf, t->type); 119 if (ptr_type_id < 0) 120 goto print_ptr_value; 121 ptr_type = btf__type_by_id(d->btf, ptr_type_id); 122 if (!ptr_type || !btf_is_func_proto(ptr_type)) 123 goto print_ptr_value; 124 125 if (!dump_prog_id_as_func_ptr(d, ptr_type, value)) 126 return; 127 128 print_ptr_value: 129 if (d->is_plain_text) 130 jsonw_printf(d->jw, "\"%p\"", (void *)value); 131 else 132 jsonw_printf(d->jw, "%lu", value); 133 } 134 135 static int btf_dumper_modifier(const struct btf_dumper *d, __u32 type_id, 136 __u8 bit_offset, const void *data) 137 { 138 int actual_type_id; 139 140 actual_type_id = btf__resolve_type(d->btf, type_id); 141 if (actual_type_id < 0) 142 return actual_type_id; 143 144 return btf_dumper_do_type(d, actual_type_id, bit_offset, data); 145 } 146 147 static int btf_dumper_enum(const struct btf_dumper *d, 148 const struct btf_type *t, 149 const void *data) 150 { 151 const struct btf_enum *enums = btf_enum(t); 152 __s64 value; 153 __u16 i; 154 155 switch (t->size) { 156 case 8: 157 value = *(__s64 *)data; 158 break; 159 case 4: 160 value = *(__s32 *)data; 161 break; 162 case 2: 163 value = *(__s16 *)data; 164 break; 165 case 1: 166 value = *(__s8 *)data; 167 break; 168 default: 169 return -EINVAL; 170 } 171 172 for (i = 0; i < btf_vlen(t); i++) { 173 if (value == enums[i].val) { 174 jsonw_string(d->jw, 175 btf__name_by_offset(d->btf, 176 enums[i].name_off)); 177 return 0; 178 } 179 } 180 181 jsonw_int(d->jw, value); 182 return 0; 183 } 184 185 static int btf_dumper_enum64(const struct btf_dumper *d, 186 const struct btf_type *t, 187 const void *data) 188 { 189 const struct btf_enum64 *enums = btf_enum64(t); 190 __u32 val_lo32, val_hi32; 191 __u64 value; 192 __u16 i; 193 194 value = *(__u64 *)data; 195 val_lo32 = (__u32)value; 196 val_hi32 = value >> 32; 197 198 for (i = 0; i < btf_vlen(t); i++) { 199 if (val_lo32 == enums[i].val_lo32 && val_hi32 == enums[i].val_hi32) { 200 jsonw_string(d->jw, 201 btf__name_by_offset(d->btf, 202 enums[i].name_off)); 203 return 0; 204 } 205 } 206 207 jsonw_int(d->jw, value); 208 return 0; 209 } 210 211 static bool is_str_array(const struct btf *btf, const struct btf_array *arr, 212 const char *s) 213 { 214 const struct btf_type *elem_type; 215 const char *end_s; 216 217 if (!arr->nelems) 218 return false; 219 220 elem_type = btf__type_by_id(btf, arr->type); 221 /* Not skipping typedef. typedef to char does not count as 222 * a string now. 223 */ 224 while (elem_type && btf_is_mod(elem_type)) 225 elem_type = btf__type_by_id(btf, elem_type->type); 226 227 if (!elem_type || !btf_is_int(elem_type) || elem_type->size != 1) 228 return false; 229 230 if (btf_int_encoding(elem_type) != BTF_INT_CHAR && 231 strcmp("char", btf__name_by_offset(btf, elem_type->name_off))) 232 return false; 233 234 end_s = s + arr->nelems; 235 while (s < end_s) { 236 if (!*s) 237 return true; 238 if (*s <= 0x1f || *s >= 0x7f) 239 return false; 240 s++; 241 } 242 243 /* '\0' is not found */ 244 return false; 245 } 246 247 static int btf_dumper_array(const struct btf_dumper *d, __u32 type_id, 248 const void *data) 249 { 250 const struct btf_type *t = btf__type_by_id(d->btf, type_id); 251 struct btf_array *arr = (struct btf_array *)(t + 1); 252 long long elem_size; 253 int ret = 0; 254 __u32 i; 255 256 if (is_str_array(d->btf, arr, data)) { 257 jsonw_string(d->jw, data); 258 return 0; 259 } 260 261 elem_size = btf__resolve_size(d->btf, arr->type); 262 if (elem_size < 0) 263 return elem_size; 264 265 jsonw_start_array(d->jw); 266 for (i = 0; i < arr->nelems; i++) { 267 ret = btf_dumper_do_type(d, arr->type, 0, 268 data + i * elem_size); 269 if (ret) 270 break; 271 } 272 273 jsonw_end_array(d->jw); 274 return ret; 275 } 276 277 static void btf_int128_print(json_writer_t *jw, const void *data, 278 bool is_plain_text) 279 { 280 /* data points to a __int128 number. 281 * Suppose 282 * int128_num = *(__int128 *)data; 283 * The below formulas shows what upper_num and lower_num represents: 284 * upper_num = int128_num >> 64; 285 * lower_num = int128_num & 0xffffffffFFFFFFFFULL; 286 */ 287 __u64 upper_num, lower_num; 288 289 #ifdef __BIG_ENDIAN_BITFIELD 290 upper_num = *(__u64 *)data; 291 lower_num = *(__u64 *)(data + 8); 292 #else 293 upper_num = *(__u64 *)(data + 8); 294 lower_num = *(__u64 *)data; 295 #endif 296 297 if (is_plain_text) { 298 if (upper_num == 0) 299 jsonw_printf(jw, "0x%llx", lower_num); 300 else 301 jsonw_printf(jw, "0x%llx%016llx", upper_num, lower_num); 302 } else { 303 if (upper_num == 0) 304 jsonw_printf(jw, "\"0x%llx\"", lower_num); 305 else 306 jsonw_printf(jw, "\"0x%llx%016llx\"", upper_num, lower_num); 307 } 308 } 309 310 static void btf_int128_shift(__u64 *print_num, __u16 left_shift_bits, 311 __u16 right_shift_bits) 312 { 313 __u64 upper_num, lower_num; 314 315 #ifdef __BIG_ENDIAN_BITFIELD 316 upper_num = print_num[0]; 317 lower_num = print_num[1]; 318 #else 319 upper_num = print_num[1]; 320 lower_num = print_num[0]; 321 #endif 322 323 /* shake out un-needed bits by shift/or operations */ 324 if (left_shift_bits >= 64) { 325 upper_num = lower_num << (left_shift_bits - 64); 326 lower_num = 0; 327 } else { 328 upper_num = (upper_num << left_shift_bits) | 329 (lower_num >> (64 - left_shift_bits)); 330 lower_num = lower_num << left_shift_bits; 331 } 332 333 if (right_shift_bits >= 64) { 334 lower_num = upper_num >> (right_shift_bits - 64); 335 upper_num = 0; 336 } else { 337 lower_num = (lower_num >> right_shift_bits) | 338 (upper_num << (64 - right_shift_bits)); 339 upper_num = upper_num >> right_shift_bits; 340 } 341 342 #ifdef __BIG_ENDIAN_BITFIELD 343 print_num[0] = upper_num; 344 print_num[1] = lower_num; 345 #else 346 print_num[0] = lower_num; 347 print_num[1] = upper_num; 348 #endif 349 } 350 351 static void btf_dumper_bitfield(__u32 nr_bits, __u8 bit_offset, 352 const void *data, json_writer_t *jw, 353 bool is_plain_text) 354 { 355 int left_shift_bits, right_shift_bits; 356 __u64 print_num[2] = {}; 357 int bytes_to_copy; 358 int bits_to_copy; 359 360 bits_to_copy = bit_offset + nr_bits; 361 bytes_to_copy = BITS_ROUNDUP_BYTES(bits_to_copy); 362 363 memcpy(print_num, data, bytes_to_copy); 364 #if defined(__BIG_ENDIAN_BITFIELD) 365 left_shift_bits = bit_offset; 366 #elif defined(__LITTLE_ENDIAN_BITFIELD) 367 left_shift_bits = 128 - bits_to_copy; 368 #else 369 #error neither big nor little endian 370 #endif 371 right_shift_bits = 128 - nr_bits; 372 373 btf_int128_shift(print_num, left_shift_bits, right_shift_bits); 374 btf_int128_print(jw, print_num, is_plain_text); 375 } 376 377 378 static void btf_dumper_int_bits(__u32 int_type, __u8 bit_offset, 379 const void *data, json_writer_t *jw, 380 bool is_plain_text) 381 { 382 int nr_bits = BTF_INT_BITS(int_type); 383 int total_bits_offset; 384 385 /* bits_offset is at most 7. 386 * BTF_INT_OFFSET() cannot exceed 128 bits. 387 */ 388 total_bits_offset = bit_offset + BTF_INT_OFFSET(int_type); 389 data += BITS_ROUNDDOWN_BYTES(total_bits_offset); 390 bit_offset = BITS_PER_BYTE_MASKED(total_bits_offset); 391 btf_dumper_bitfield(nr_bits, bit_offset, data, jw, 392 is_plain_text); 393 } 394 395 static int btf_dumper_int(const struct btf_type *t, __u8 bit_offset, 396 const void *data, json_writer_t *jw, 397 bool is_plain_text) 398 { 399 __u32 *int_type; 400 __u32 nr_bits; 401 402 int_type = (__u32 *)(t + 1); 403 nr_bits = BTF_INT_BITS(*int_type); 404 /* if this is bit field */ 405 if (bit_offset || BTF_INT_OFFSET(*int_type) || 406 BITS_PER_BYTE_MASKED(nr_bits)) { 407 btf_dumper_int_bits(*int_type, bit_offset, data, jw, 408 is_plain_text); 409 return 0; 410 } 411 412 if (nr_bits == 128) { 413 btf_int128_print(jw, data, is_plain_text); 414 return 0; 415 } 416 417 switch (BTF_INT_ENCODING(*int_type)) { 418 case 0: 419 if (BTF_INT_BITS(*int_type) == 64) 420 jsonw_printf(jw, "%llu", *(__u64 *)data); 421 else if (BTF_INT_BITS(*int_type) == 32) 422 jsonw_printf(jw, "%u", *(__u32 *)data); 423 else if (BTF_INT_BITS(*int_type) == 16) 424 jsonw_printf(jw, "%hu", *(__u16 *)data); 425 else if (BTF_INT_BITS(*int_type) == 8) 426 jsonw_printf(jw, "%hhu", *(__u8 *)data); 427 else 428 btf_dumper_int_bits(*int_type, bit_offset, data, jw, 429 is_plain_text); 430 break; 431 case BTF_INT_SIGNED: 432 if (BTF_INT_BITS(*int_type) == 64) 433 jsonw_printf(jw, "%lld", *(long long *)data); 434 else if (BTF_INT_BITS(*int_type) == 32) 435 jsonw_printf(jw, "%d", *(int *)data); 436 else if (BTF_INT_BITS(*int_type) == 16) 437 jsonw_printf(jw, "%hd", *(short *)data); 438 else if (BTF_INT_BITS(*int_type) == 8) 439 jsonw_printf(jw, "%hhd", *(char *)data); 440 else 441 btf_dumper_int_bits(*int_type, bit_offset, data, jw, 442 is_plain_text); 443 break; 444 case BTF_INT_CHAR: 445 if (isprint(*(char *)data)) 446 jsonw_printf(jw, "\"%c\"", *(char *)data); 447 else 448 if (is_plain_text) 449 jsonw_printf(jw, "0x%hhx", *(char *)data); 450 else 451 jsonw_printf(jw, "\"\\u00%02hhx\"", 452 *(char *)data); 453 break; 454 case BTF_INT_BOOL: 455 jsonw_bool(jw, *(bool *)data); 456 break; 457 default: 458 /* shouldn't happen */ 459 return -EINVAL; 460 } 461 462 return 0; 463 } 464 465 static int btf_dumper_struct(const struct btf_dumper *d, __u32 type_id, 466 const void *data) 467 { 468 const struct btf_type *t; 469 struct btf_member *m; 470 const void *data_off; 471 int kind_flag; 472 int ret = 0; 473 int i, vlen; 474 475 t = btf__type_by_id(d->btf, type_id); 476 if (!t) 477 return -EINVAL; 478 479 kind_flag = BTF_INFO_KFLAG(t->info); 480 vlen = BTF_INFO_VLEN(t->info); 481 jsonw_start_object(d->jw); 482 m = (struct btf_member *)(t + 1); 483 484 for (i = 0; i < vlen; i++) { 485 __u32 bit_offset = m[i].offset; 486 __u32 bitfield_size = 0; 487 488 if (kind_flag) { 489 bitfield_size = BTF_MEMBER_BITFIELD_SIZE(bit_offset); 490 bit_offset = BTF_MEMBER_BIT_OFFSET(bit_offset); 491 } 492 493 jsonw_name(d->jw, btf__name_by_offset(d->btf, m[i].name_off)); 494 data_off = data + BITS_ROUNDDOWN_BYTES(bit_offset); 495 if (bitfield_size) { 496 btf_dumper_bitfield(bitfield_size, 497 BITS_PER_BYTE_MASKED(bit_offset), 498 data_off, d->jw, d->is_plain_text); 499 } else { 500 ret = btf_dumper_do_type(d, m[i].type, 501 BITS_PER_BYTE_MASKED(bit_offset), 502 data_off); 503 if (ret) 504 break; 505 } 506 } 507 508 jsonw_end_object(d->jw); 509 510 return ret; 511 } 512 513 static int btf_dumper_var(const struct btf_dumper *d, __u32 type_id, 514 __u8 bit_offset, const void *data) 515 { 516 const struct btf_type *t = btf__type_by_id(d->btf, type_id); 517 int ret; 518 519 jsonw_start_object(d->jw); 520 jsonw_name(d->jw, btf__name_by_offset(d->btf, t->name_off)); 521 ret = btf_dumper_do_type(d, t->type, bit_offset, data); 522 jsonw_end_object(d->jw); 523 524 return ret; 525 } 526 527 static int btf_dumper_datasec(const struct btf_dumper *d, __u32 type_id, 528 const void *data) 529 { 530 struct btf_var_secinfo *vsi; 531 const struct btf_type *t; 532 int ret = 0, i, vlen; 533 534 t = btf__type_by_id(d->btf, type_id); 535 if (!t) 536 return -EINVAL; 537 538 vlen = BTF_INFO_VLEN(t->info); 539 vsi = (struct btf_var_secinfo *)(t + 1); 540 541 jsonw_start_object(d->jw); 542 jsonw_name(d->jw, btf__name_by_offset(d->btf, t->name_off)); 543 jsonw_start_array(d->jw); 544 for (i = 0; i < vlen; i++) { 545 ret = btf_dumper_do_type(d, vsi[i].type, 0, data + vsi[i].offset); 546 if (ret) 547 break; 548 } 549 jsonw_end_array(d->jw); 550 jsonw_end_object(d->jw); 551 552 return ret; 553 } 554 555 static int btf_dumper_do_type(const struct btf_dumper *d, __u32 type_id, 556 __u8 bit_offset, const void *data) 557 { 558 const struct btf_type *t = btf__type_by_id(d->btf, type_id); 559 560 switch (BTF_INFO_KIND(t->info)) { 561 case BTF_KIND_INT: 562 return btf_dumper_int(t, bit_offset, data, d->jw, 563 d->is_plain_text); 564 case BTF_KIND_STRUCT: 565 case BTF_KIND_UNION: 566 return btf_dumper_struct(d, type_id, data); 567 case BTF_KIND_ARRAY: 568 return btf_dumper_array(d, type_id, data); 569 case BTF_KIND_ENUM: 570 return btf_dumper_enum(d, t, data); 571 case BTF_KIND_ENUM64: 572 return btf_dumper_enum64(d, t, data); 573 case BTF_KIND_PTR: 574 btf_dumper_ptr(d, t, data); 575 return 0; 576 case BTF_KIND_UNKN: 577 jsonw_printf(d->jw, "(unknown)"); 578 return 0; 579 case BTF_KIND_FWD: 580 /* map key or value can't be forward */ 581 jsonw_printf(d->jw, "(fwd-kind-invalid)"); 582 return -EINVAL; 583 case BTF_KIND_TYPEDEF: 584 case BTF_KIND_VOLATILE: 585 case BTF_KIND_CONST: 586 case BTF_KIND_RESTRICT: 587 return btf_dumper_modifier(d, type_id, bit_offset, data); 588 case BTF_KIND_VAR: 589 return btf_dumper_var(d, type_id, bit_offset, data); 590 case BTF_KIND_DATASEC: 591 return btf_dumper_datasec(d, type_id, data); 592 default: 593 jsonw_printf(d->jw, "(unsupported-kind"); 594 return -EINVAL; 595 } 596 } 597 598 int btf_dumper_type(const struct btf_dumper *d, __u32 type_id, 599 const void *data) 600 { 601 return btf_dumper_do_type(d, type_id, 0, data); 602 } 603 604 #define BTF_PRINT_ARG(...) \ 605 do { \ 606 pos += snprintf(func_sig + pos, size - pos, \ 607 __VA_ARGS__); \ 608 if (pos >= size) \ 609 return -1; \ 610 } while (0) 611 #define BTF_PRINT_TYPE(type) \ 612 do { \ 613 pos = __btf_dumper_type_only(btf, type, func_sig, \ 614 pos, size); \ 615 if (pos == -1) \ 616 return -1; \ 617 } while (0) 618 619 static int __btf_dumper_type_only(const struct btf *btf, __u32 type_id, 620 char *func_sig, int pos, int size) 621 { 622 const struct btf_type *proto_type; 623 const struct btf_array *array; 624 const struct btf_var *var; 625 const struct btf_type *t; 626 627 if (!type_id) { 628 BTF_PRINT_ARG("void "); 629 return pos; 630 } 631 632 t = btf__type_by_id(btf, type_id); 633 634 switch (BTF_INFO_KIND(t->info)) { 635 case BTF_KIND_INT: 636 case BTF_KIND_TYPEDEF: 637 case BTF_KIND_FLOAT: 638 BTF_PRINT_ARG("%s ", btf__name_by_offset(btf, t->name_off)); 639 break; 640 case BTF_KIND_STRUCT: 641 BTF_PRINT_ARG("struct %s ", 642 btf__name_by_offset(btf, t->name_off)); 643 break; 644 case BTF_KIND_UNION: 645 BTF_PRINT_ARG("union %s ", 646 btf__name_by_offset(btf, t->name_off)); 647 break; 648 case BTF_KIND_ENUM: 649 case BTF_KIND_ENUM64: 650 BTF_PRINT_ARG("enum %s ", 651 btf__name_by_offset(btf, t->name_off)); 652 break; 653 case BTF_KIND_ARRAY: 654 array = (struct btf_array *)(t + 1); 655 BTF_PRINT_TYPE(array->type); 656 BTF_PRINT_ARG("[%d]", array->nelems); 657 break; 658 case BTF_KIND_PTR: 659 BTF_PRINT_TYPE(t->type); 660 BTF_PRINT_ARG("* "); 661 break; 662 case BTF_KIND_FWD: 663 BTF_PRINT_ARG("%s %s ", 664 BTF_INFO_KFLAG(t->info) ? "union" : "struct", 665 btf__name_by_offset(btf, t->name_off)); 666 break; 667 case BTF_KIND_VOLATILE: 668 BTF_PRINT_ARG("volatile "); 669 BTF_PRINT_TYPE(t->type); 670 break; 671 case BTF_KIND_CONST: 672 BTF_PRINT_ARG("const "); 673 BTF_PRINT_TYPE(t->type); 674 break; 675 case BTF_KIND_RESTRICT: 676 BTF_PRINT_ARG("restrict "); 677 BTF_PRINT_TYPE(t->type); 678 break; 679 case BTF_KIND_FUNC_PROTO: 680 pos = btf_dump_func(btf, func_sig, t, NULL, pos, size); 681 if (pos == -1) 682 return -1; 683 break; 684 case BTF_KIND_FUNC: 685 proto_type = btf__type_by_id(btf, t->type); 686 pos = btf_dump_func(btf, func_sig, proto_type, t, pos, size); 687 if (pos == -1) 688 return -1; 689 break; 690 case BTF_KIND_VAR: 691 var = (struct btf_var *)(t + 1); 692 if (var->linkage == BTF_VAR_STATIC) 693 BTF_PRINT_ARG("static "); 694 BTF_PRINT_TYPE(t->type); 695 BTF_PRINT_ARG(" %s", 696 btf__name_by_offset(btf, t->name_off)); 697 break; 698 case BTF_KIND_DATASEC: 699 BTF_PRINT_ARG("section (\"%s\") ", 700 btf__name_by_offset(btf, t->name_off)); 701 break; 702 case BTF_KIND_UNKN: 703 default: 704 return -1; 705 } 706 707 return pos; 708 } 709 710 static int btf_dump_func(const struct btf *btf, char *func_sig, 711 const struct btf_type *func_proto, 712 const struct btf_type *func, int pos, int size) 713 { 714 int i, vlen; 715 716 BTF_PRINT_TYPE(func_proto->type); 717 if (func) 718 BTF_PRINT_ARG("%s(", btf__name_by_offset(btf, func->name_off)); 719 else 720 BTF_PRINT_ARG("("); 721 vlen = BTF_INFO_VLEN(func_proto->info); 722 for (i = 0; i < vlen; i++) { 723 struct btf_param *arg = &((struct btf_param *)(func_proto + 1))[i]; 724 725 if (i) 726 BTF_PRINT_ARG(", "); 727 if (arg->type) { 728 BTF_PRINT_TYPE(arg->type); 729 if (arg->name_off) 730 BTF_PRINT_ARG("%s", 731 btf__name_by_offset(btf, arg->name_off)); 732 else if (pos && func_sig[pos - 1] == ' ') 733 /* Remove unnecessary space for 734 * FUNC_PROTO that does not have 735 * arg->name_off 736 */ 737 func_sig[--pos] = '\0'; 738 } else { 739 BTF_PRINT_ARG("..."); 740 } 741 } 742 BTF_PRINT_ARG(")"); 743 744 return pos; 745 } 746 747 void btf_dumper_type_only(const struct btf *btf, __u32 type_id, char *func_sig, 748 int size) 749 { 750 int err; 751 752 func_sig[0] = '\0'; 753 if (!btf) 754 return; 755 756 err = __btf_dumper_type_only(btf, type_id, func_sig, 0, size); 757 if (err < 0) 758 func_sig[0] = '\0'; 759 } 760 761 static const char *ltrim(const char *s) 762 { 763 while (isspace(*s)) 764 s++; 765 766 return s; 767 } 768 769 void btf_dump_linfo_plain(const struct btf *btf, 770 const struct bpf_line_info *linfo, 771 const char *prefix, bool linum) 772 { 773 const char *line = btf__name_by_offset(btf, linfo->line_off); 774 775 if (!line) 776 return; 777 line = ltrim(line); 778 779 if (!prefix) 780 prefix = ""; 781 782 if (linum) { 783 const char *file = btf__name_by_offset(btf, linfo->file_name_off); 784 785 /* More forgiving on file because linum option is 786 * expected to provide more info than the already 787 * available src line. 788 */ 789 if (!file) 790 file = ""; 791 792 printf("%s%s [file:%s line_num:%u line_col:%u]\n", 793 prefix, line, file, 794 BPF_LINE_INFO_LINE_NUM(linfo->line_col), 795 BPF_LINE_INFO_LINE_COL(linfo->line_col)); 796 } else { 797 printf("%s%s\n", prefix, line); 798 } 799 } 800 801 void btf_dump_linfo_json(const struct btf *btf, 802 const struct bpf_line_info *linfo, bool linum) 803 { 804 const char *line = btf__name_by_offset(btf, linfo->line_off); 805 806 if (line) 807 jsonw_string_field(json_wtr, "src", ltrim(line)); 808 809 if (linum) { 810 const char *file = btf__name_by_offset(btf, linfo->file_name_off); 811 812 if (file) 813 jsonw_string_field(json_wtr, "file", file); 814 815 if (BPF_LINE_INFO_LINE_NUM(linfo->line_col)) 816 jsonw_int_field(json_wtr, "line_num", 817 BPF_LINE_INFO_LINE_NUM(linfo->line_col)); 818 819 if (BPF_LINE_INFO_LINE_COL(linfo->line_col)) 820 jsonw_int_field(json_wtr, "line_col", 821 BPF_LINE_INFO_LINE_COL(linfo->line_col)); 822 } 823 } 824 825 static void dotlabel_puts(const char *s) 826 { 827 for (; *s; ++s) { 828 switch (*s) { 829 case '\\': 830 case '"': 831 case '{': 832 case '}': 833 case '<': 834 case '>': 835 case '|': 836 case ' ': 837 putchar('\\'); 838 fallthrough; 839 default: 840 putchar(*s); 841 } 842 } 843 } 844 845 static const char *shorten_path(const char *path) 846 { 847 const unsigned int MAX_PATH_LEN = 32; 848 size_t len = strlen(path); 849 const char *shortpath; 850 851 if (len <= MAX_PATH_LEN) 852 return path; 853 854 /* Search for last '/' under the MAX_PATH_LEN limit */ 855 shortpath = strchr(path + len - MAX_PATH_LEN, '/'); 856 if (shortpath) { 857 if (shortpath < path + strlen("...")) 858 /* We removed a very short prefix, e.g. "/w", and we'll 859 * make the path longer by prefixing with the ellipsis. 860 * Not worth it, keep initial path. 861 */ 862 return path; 863 return shortpath; 864 } 865 866 /* File base name length is > MAX_PATH_LEN, search for last '/' */ 867 shortpath = strrchr(path, '/'); 868 if (shortpath) 869 return shortpath; 870 871 return path; 872 } 873 874 void btf_dump_linfo_dotlabel(const struct btf *btf, 875 const struct bpf_line_info *linfo, bool linum) 876 { 877 const char *line = btf__name_by_offset(btf, linfo->line_off); 878 879 if (!line || !strlen(line)) 880 return; 881 line = ltrim(line); 882 883 if (linum) { 884 const char *file = btf__name_by_offset(btf, linfo->file_name_off); 885 const char *shortfile; 886 887 /* More forgiving on file because linum option is 888 * expected to provide more info than the already 889 * available src line. 890 */ 891 if (!file) 892 shortfile = ""; 893 else 894 shortfile = shorten_path(file); 895 896 printf("; [%s", shortfile > file ? "..." : ""); 897 dotlabel_puts(shortfile); 898 printf(" line:%u col:%u]\\l\\\n", 899 BPF_LINE_INFO_LINE_NUM(linfo->line_col), 900 BPF_LINE_INFO_LINE_COL(linfo->line_col)); 901 } 902 903 printf("; "); 904 dotlabel_puts(line); 905 printf("\\l\\\n"); 906 } 907