dt_module.c revision 296816
1/* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License (the "License"). 6 * You may not use this file except in compliance with the License. 7 * 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9 * or http://www.opensolaris.org/os/licensing. 10 * See the License for the specific language governing permissions 11 * and limitations under the License. 12 * 13 * When distributing Covered Code, include this CDDL HEADER in each 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15 * If applicable, add the following below this CDDL HEADER, with the 16 * fields enclosed by brackets "[]" replaced with your own identifying 17 * information: Portions Copyright [yyyy] [name of copyright owner] 18 * 19 * CDDL HEADER END 20 */ 21 22/* 23 * Copyright (c) 2003, 2010, Oracle and/or its affiliates. All rights reserved. 24 */ 25/* 26 * Copyright (c) 2013, Joyent, Inc. All rights reserved. 27 * Copyright (c) 2016, Pedro Giffuni. All rights reserved. 28 */ 29 30#include <sys/types.h> 31#ifdef illumos 32#include <sys/modctl.h> 33#include <sys/kobj.h> 34#include <sys/kobj_impl.h> 35#include <sys/sysmacros.h> 36#include <sys/elf.h> 37#include <sys/task.h> 38#else 39#include <sys/param.h> 40#include <sys/linker.h> 41#include <sys/module.h> 42#include <sys/stat.h> 43#endif 44 45#include <unistd.h> 46#ifdef illumos 47#include <project.h> 48#endif 49#include <strings.h> 50#include <stdlib.h> 51#include <libelf.h> 52#include <limits.h> 53#include <assert.h> 54#include <errno.h> 55#include <dirent.h> 56#ifndef illumos 57#include <fcntl.h> 58#include <libproc_compat.h> 59#endif 60 61#include <dt_strtab.h> 62#include <dt_module.h> 63#include <dt_impl.h> 64 65static const char *dt_module_strtab; /* active strtab for qsort callbacks */ 66 67static void 68dt_module_symhash_insert(dt_module_t *dmp, const char *name, uint_t id) 69{ 70 dt_sym_t *dsp = &dmp->dm_symchains[dmp->dm_symfree]; 71 uint_t h; 72 73 assert(dmp->dm_symfree < dmp->dm_nsymelems + 1); 74 75 dsp->ds_symid = id; 76 h = dt_strtab_hash(name, NULL) % dmp->dm_nsymbuckets; 77 dsp->ds_next = dmp->dm_symbuckets[h]; 78 dmp->dm_symbuckets[h] = dmp->dm_symfree++; 79} 80 81static uint_t 82dt_module_syminit32(dt_module_t *dmp) 83{ 84#if STT_NUM != (STT_TLS + 1) 85#error "STT_NUM has grown. update dt_module_syminit32()" 86#endif 87 88 Elf32_Sym *sym = dmp->dm_symtab.cts_data; 89 const char *base = dmp->dm_strtab.cts_data; 90 size_t ss_size = dmp->dm_strtab.cts_size; 91 uint_t i, n = dmp->dm_nsymelems; 92 uint_t asrsv = 0; 93 94#if defined(__FreeBSD__) 95 GElf_Ehdr ehdr; 96 int is_elf_obj; 97 98 gelf_getehdr(dmp->dm_elf, &ehdr); 99 is_elf_obj = (ehdr.e_type == ET_REL); 100#endif 101 102 for (i = 0; i < n; i++, sym++) { 103 const char *name = base + sym->st_name; 104 uchar_t type = ELF32_ST_TYPE(sym->st_info); 105 106 if (type >= STT_NUM || type == STT_SECTION) 107 continue; /* skip sections and unknown types */ 108 109 if (sym->st_name == 0 || sym->st_name >= ss_size) 110 continue; /* skip null or invalid names */ 111 112 if (sym->st_value != 0 && 113 (ELF32_ST_BIND(sym->st_info) != STB_LOCAL || sym->st_size)) { 114 asrsv++; /* reserve space in the address map */ 115 116#if defined(__FreeBSD__) 117 sym->st_value += (Elf_Addr) dmp->dm_reloc_offset; 118 if (is_elf_obj && sym->st_shndx != SHN_UNDEF && 119 sym->st_shndx < ehdr.e_shnum) 120 sym->st_value += 121 dmp->dm_sec_offsets[sym->st_shndx]; 122#endif 123 } 124 125 dt_module_symhash_insert(dmp, name, i); 126 } 127 128 return (asrsv); 129} 130 131static uint_t 132dt_module_syminit64(dt_module_t *dmp) 133{ 134#if STT_NUM != (STT_TLS + 1) 135#error "STT_NUM has grown. update dt_module_syminit64()" 136#endif 137 138 Elf64_Sym *sym = dmp->dm_symtab.cts_data; 139 const char *base = dmp->dm_strtab.cts_data; 140 size_t ss_size = dmp->dm_strtab.cts_size; 141 uint_t i, n = dmp->dm_nsymelems; 142 uint_t asrsv = 0; 143 144#if defined(__FreeBSD__) 145 GElf_Ehdr ehdr; 146 int is_elf_obj; 147 148 gelf_getehdr(dmp->dm_elf, &ehdr); 149 is_elf_obj = (ehdr.e_type == ET_REL); 150#endif 151 152 for (i = 0; i < n; i++, sym++) { 153 const char *name = base + sym->st_name; 154 uchar_t type = ELF64_ST_TYPE(sym->st_info); 155 156 if (type >= STT_NUM || type == STT_SECTION) 157 continue; /* skip sections and unknown types */ 158 159 if (sym->st_name == 0 || sym->st_name >= ss_size) 160 continue; /* skip null or invalid names */ 161 162 if (sym->st_value != 0 && 163 (ELF64_ST_BIND(sym->st_info) != STB_LOCAL || sym->st_size)) { 164 asrsv++; /* reserve space in the address map */ 165#if defined(__FreeBSD__) 166 sym->st_value += (Elf_Addr) dmp->dm_reloc_offset; 167 if (is_elf_obj && sym->st_shndx != SHN_UNDEF && 168 sym->st_shndx < ehdr.e_shnum) 169 sym->st_value += 170 dmp->dm_sec_offsets[sym->st_shndx]; 171#endif 172 } 173 174 dt_module_symhash_insert(dmp, name, i); 175 } 176 177 return (asrsv); 178} 179 180/* 181 * Sort comparison function for 32-bit symbol address-to-name lookups. We sort 182 * symbols by value. If values are equal, we prefer the symbol that is 183 * non-zero sized, typed, not weak, or lexically first, in that order. 184 */ 185static int 186dt_module_symcomp32(const void *lp, const void *rp) 187{ 188 Elf32_Sym *lhs = *((Elf32_Sym **)lp); 189 Elf32_Sym *rhs = *((Elf32_Sym **)rp); 190 191 if (lhs->st_value != rhs->st_value) 192 return (lhs->st_value > rhs->st_value ? 1 : -1); 193 194 if ((lhs->st_size == 0) != (rhs->st_size == 0)) 195 return (lhs->st_size == 0 ? 1 : -1); 196 197 if ((ELF32_ST_TYPE(lhs->st_info) == STT_NOTYPE) != 198 (ELF32_ST_TYPE(rhs->st_info) == STT_NOTYPE)) 199 return (ELF32_ST_TYPE(lhs->st_info) == STT_NOTYPE ? 1 : -1); 200 201 if ((ELF32_ST_BIND(lhs->st_info) == STB_WEAK) != 202 (ELF32_ST_BIND(rhs->st_info) == STB_WEAK)) 203 return (ELF32_ST_BIND(lhs->st_info) == STB_WEAK ? 1 : -1); 204 205 return (strcmp(dt_module_strtab + lhs->st_name, 206 dt_module_strtab + rhs->st_name)); 207} 208 209/* 210 * Sort comparison function for 64-bit symbol address-to-name lookups. We sort 211 * symbols by value. If values are equal, we prefer the symbol that is 212 * non-zero sized, typed, not weak, or lexically first, in that order. 213 */ 214static int 215dt_module_symcomp64(const void *lp, const void *rp) 216{ 217 Elf64_Sym *lhs = *((Elf64_Sym **)lp); 218 Elf64_Sym *rhs = *((Elf64_Sym **)rp); 219 220 if (lhs->st_value != rhs->st_value) 221 return (lhs->st_value > rhs->st_value ? 1 : -1); 222 223 if ((lhs->st_size == 0) != (rhs->st_size == 0)) 224 return (lhs->st_size == 0 ? 1 : -1); 225 226 if ((ELF64_ST_TYPE(lhs->st_info) == STT_NOTYPE) != 227 (ELF64_ST_TYPE(rhs->st_info) == STT_NOTYPE)) 228 return (ELF64_ST_TYPE(lhs->st_info) == STT_NOTYPE ? 1 : -1); 229 230 if ((ELF64_ST_BIND(lhs->st_info) == STB_WEAK) != 231 (ELF64_ST_BIND(rhs->st_info) == STB_WEAK)) 232 return (ELF64_ST_BIND(lhs->st_info) == STB_WEAK ? 1 : -1); 233 234 return (strcmp(dt_module_strtab + lhs->st_name, 235 dt_module_strtab + rhs->st_name)); 236} 237 238static void 239dt_module_symsort32(dt_module_t *dmp) 240{ 241 Elf32_Sym *symtab = (Elf32_Sym *)dmp->dm_symtab.cts_data; 242 Elf32_Sym **sympp = (Elf32_Sym **)dmp->dm_asmap; 243 const dt_sym_t *dsp = dmp->dm_symchains + 1; 244 uint_t i, n = dmp->dm_symfree; 245 246 for (i = 1; i < n; i++, dsp++) { 247 Elf32_Sym *sym = symtab + dsp->ds_symid; 248 if (sym->st_value != 0 && 249 (ELF32_ST_BIND(sym->st_info) != STB_LOCAL || sym->st_size)) 250 *sympp++ = sym; 251 } 252 253 dmp->dm_aslen = (uint_t)(sympp - (Elf32_Sym **)dmp->dm_asmap); 254 assert(dmp->dm_aslen <= dmp->dm_asrsv); 255 256 dt_module_strtab = dmp->dm_strtab.cts_data; 257 qsort(dmp->dm_asmap, dmp->dm_aslen, 258 sizeof (Elf32_Sym *), dt_module_symcomp32); 259 dt_module_strtab = NULL; 260} 261 262static void 263dt_module_symsort64(dt_module_t *dmp) 264{ 265 Elf64_Sym *symtab = (Elf64_Sym *)dmp->dm_symtab.cts_data; 266 Elf64_Sym **sympp = (Elf64_Sym **)dmp->dm_asmap; 267 const dt_sym_t *dsp = dmp->dm_symchains + 1; 268 uint_t i, n = dmp->dm_symfree; 269 270 for (i = 1; i < n; i++, dsp++) { 271 Elf64_Sym *sym = symtab + dsp->ds_symid; 272 if (sym->st_value != 0 && 273 (ELF64_ST_BIND(sym->st_info) != STB_LOCAL || sym->st_size)) 274 *sympp++ = sym; 275 } 276 277 dmp->dm_aslen = (uint_t)(sympp - (Elf64_Sym **)dmp->dm_asmap); 278 assert(dmp->dm_aslen <= dmp->dm_asrsv); 279 280 dt_module_strtab = dmp->dm_strtab.cts_data; 281 qsort(dmp->dm_asmap, dmp->dm_aslen, 282 sizeof (Elf64_Sym *), dt_module_symcomp64); 283 dt_module_strtab = NULL; 284} 285 286static GElf_Sym * 287dt_module_symgelf32(const Elf32_Sym *src, GElf_Sym *dst) 288{ 289 if (dst != NULL) { 290 dst->st_name = src->st_name; 291 dst->st_info = src->st_info; 292 dst->st_other = src->st_other; 293 dst->st_shndx = src->st_shndx; 294 dst->st_value = src->st_value; 295 dst->st_size = src->st_size; 296 } 297 298 return (dst); 299} 300 301static GElf_Sym * 302dt_module_symgelf64(const Elf64_Sym *src, GElf_Sym *dst) 303{ 304 if (dst != NULL) 305 bcopy(src, dst, sizeof (GElf_Sym)); 306 307 return (dst); 308} 309 310static GElf_Sym * 311dt_module_symname32(dt_module_t *dmp, const char *name, 312 GElf_Sym *symp, uint_t *idp) 313{ 314 const Elf32_Sym *symtab = dmp->dm_symtab.cts_data; 315 const char *strtab = dmp->dm_strtab.cts_data; 316 317 const Elf32_Sym *sym; 318 const dt_sym_t *dsp; 319 uint_t i, h; 320 321 if (dmp->dm_nsymelems == 0) 322 return (NULL); 323 324 h = dt_strtab_hash(name, NULL) % dmp->dm_nsymbuckets; 325 326 for (i = dmp->dm_symbuckets[h]; i != 0; i = dsp->ds_next) { 327 dsp = &dmp->dm_symchains[i]; 328 sym = symtab + dsp->ds_symid; 329 330 if (strcmp(name, strtab + sym->st_name) == 0) { 331 if (idp != NULL) 332 *idp = dsp->ds_symid; 333 return (dt_module_symgelf32(sym, symp)); 334 } 335 } 336 337 return (NULL); 338} 339 340static GElf_Sym * 341dt_module_symname64(dt_module_t *dmp, const char *name, 342 GElf_Sym *symp, uint_t *idp) 343{ 344 const Elf64_Sym *symtab = dmp->dm_symtab.cts_data; 345 const char *strtab = dmp->dm_strtab.cts_data; 346 347 const Elf64_Sym *sym; 348 const dt_sym_t *dsp; 349 uint_t i, h; 350 351 if (dmp->dm_nsymelems == 0) 352 return (NULL); 353 354 h = dt_strtab_hash(name, NULL) % dmp->dm_nsymbuckets; 355 356 for (i = dmp->dm_symbuckets[h]; i != 0; i = dsp->ds_next) { 357 dsp = &dmp->dm_symchains[i]; 358 sym = symtab + dsp->ds_symid; 359 360 if (strcmp(name, strtab + sym->st_name) == 0) { 361 if (idp != NULL) 362 *idp = dsp->ds_symid; 363 return (dt_module_symgelf64(sym, symp)); 364 } 365 } 366 367 return (NULL); 368} 369 370static GElf_Sym * 371dt_module_symaddr32(dt_module_t *dmp, GElf_Addr addr, 372 GElf_Sym *symp, uint_t *idp) 373{ 374 const Elf32_Sym **asmap = (const Elf32_Sym **)dmp->dm_asmap; 375 const Elf32_Sym *symtab = dmp->dm_symtab.cts_data; 376 const Elf32_Sym *sym; 377 378 uint_t i, mid, lo = 0, hi = dmp->dm_aslen - 1; 379 Elf32_Addr v; 380 381 if (dmp->dm_aslen == 0) 382 return (NULL); 383 384 while (hi - lo > 1) { 385 mid = (lo + hi) / 2; 386 if (addr >= asmap[mid]->st_value) 387 lo = mid; 388 else 389 hi = mid; 390 } 391 392 i = addr < asmap[hi]->st_value ? lo : hi; 393 sym = asmap[i]; 394 v = sym->st_value; 395 396 /* 397 * If the previous entry has the same value, improve our choice. The 398 * order of equal-valued symbols is determined by the comparison func. 399 */ 400 while (i-- != 0 && asmap[i]->st_value == v) 401 sym = asmap[i]; 402 403 if (addr - sym->st_value < MAX(sym->st_size, 1)) { 404 if (idp != NULL) 405 *idp = (uint_t)(sym - symtab); 406 return (dt_module_symgelf32(sym, symp)); 407 } 408 409 return (NULL); 410} 411 412static GElf_Sym * 413dt_module_symaddr64(dt_module_t *dmp, GElf_Addr addr, 414 GElf_Sym *symp, uint_t *idp) 415{ 416 const Elf64_Sym **asmap = (const Elf64_Sym **)dmp->dm_asmap; 417 const Elf64_Sym *symtab = dmp->dm_symtab.cts_data; 418 const Elf64_Sym *sym; 419 420 uint_t i, mid, lo = 0, hi = dmp->dm_aslen - 1; 421 Elf64_Addr v; 422 423 if (dmp->dm_aslen == 0) 424 return (NULL); 425 426 while (hi - lo > 1) { 427 mid = (lo + hi) / 2; 428 if (addr >= asmap[mid]->st_value) 429 lo = mid; 430 else 431 hi = mid; 432 } 433 434 i = addr < asmap[hi]->st_value ? lo : hi; 435 sym = asmap[i]; 436 v = sym->st_value; 437 438 /* 439 * If the previous entry has the same value, improve our choice. The 440 * order of equal-valued symbols is determined by the comparison func. 441 */ 442 while (i-- != 0 && asmap[i]->st_value == v) 443 sym = asmap[i]; 444 445 if (addr - sym->st_value < MAX(sym->st_size, 1)) { 446 if (idp != NULL) 447 *idp = (uint_t)(sym - symtab); 448 return (dt_module_symgelf64(sym, symp)); 449 } 450 451 return (NULL); 452} 453 454static const dt_modops_t dt_modops_32 = { 455 dt_module_syminit32, 456 dt_module_symsort32, 457 dt_module_symname32, 458 dt_module_symaddr32 459}; 460 461static const dt_modops_t dt_modops_64 = { 462 dt_module_syminit64, 463 dt_module_symsort64, 464 dt_module_symname64, 465 dt_module_symaddr64 466}; 467 468dt_module_t * 469dt_module_create(dtrace_hdl_t *dtp, const char *name) 470{ 471 long pid; 472 char *eptr; 473 dt_ident_t *idp; 474 uint_t h = dt_strtab_hash(name, NULL) % dtp->dt_modbuckets; 475 dt_module_t *dmp; 476 477 for (dmp = dtp->dt_mods[h]; dmp != NULL; dmp = dmp->dm_next) { 478 if (strcmp(dmp->dm_name, name) == 0) 479 return (dmp); 480 } 481 482 if ((dmp = malloc(sizeof (dt_module_t))) == NULL) 483 return (NULL); /* caller must handle allocation failure */ 484 485 bzero(dmp, sizeof (dt_module_t)); 486 (void) strlcpy(dmp->dm_name, name, sizeof (dmp->dm_name)); 487 dt_list_append(&dtp->dt_modlist, dmp); 488 dmp->dm_next = dtp->dt_mods[h]; 489 dtp->dt_mods[h] = dmp; 490 dtp->dt_nmods++; 491 492 if (dtp->dt_conf.dtc_ctfmodel == CTF_MODEL_LP64) 493 dmp->dm_ops = &dt_modops_64; 494 else 495 dmp->dm_ops = &dt_modops_32; 496 497 /* 498 * Modules for userland processes are special. They always refer to a 499 * specific process and have a copy of their CTF data from a specific 500 * instant in time. Any dt_module_t that begins with 'pid' is a module 501 * for a specific process, much like how any probe description that 502 * begins with 'pid' is special. pid123 refers to process 123. A module 503 * that is just 'pid' refers specifically to pid$target. This is 504 * generally done as D does not currently allow for macros to be 505 * evaluated when working with types. 506 */ 507 if (strncmp(dmp->dm_name, "pid", 3) == 0) { 508 errno = 0; 509 if (dmp->dm_name[3] == '\0') { 510 idp = dt_idhash_lookup(dtp->dt_macros, "target"); 511 if (idp != NULL && idp->di_id != 0) 512 dmp->dm_pid = idp->di_id; 513 } else { 514 pid = strtol(dmp->dm_name + 3, &eptr, 10); 515 if (errno == 0 && *eptr == '\0') 516 dmp->dm_pid = (pid_t)pid; 517 else 518 dt_dprintf("encountered malformed pid " 519 "module: %s\n", dmp->dm_name); 520 } 521 } 522 523 return (dmp); 524} 525 526dt_module_t * 527dt_module_lookup_by_name(dtrace_hdl_t *dtp, const char *name) 528{ 529 uint_t h = dt_strtab_hash(name, NULL) % dtp->dt_modbuckets; 530 dt_module_t *dmp; 531 532 for (dmp = dtp->dt_mods[h]; dmp != NULL; dmp = dmp->dm_next) { 533 if (strcmp(dmp->dm_name, name) == 0) 534 return (dmp); 535 } 536 537 return (NULL); 538} 539 540/*ARGSUSED*/ 541dt_module_t * 542dt_module_lookup_by_ctf(dtrace_hdl_t *dtp, ctf_file_t *ctfp) 543{ 544 return (ctfp ? ctf_getspecific(ctfp) : NULL); 545} 546 547#ifdef __FreeBSD__ 548dt_kmodule_t * 549dt_kmodule_lookup(dtrace_hdl_t *dtp, const char *name) 550{ 551 uint_t h = dt_strtab_hash(name, NULL) % dtp->dt_modbuckets; 552 dt_kmodule_t *dkmp; 553 554 for (dkmp = dtp->dt_kmods[h]; dkmp != NULL; dkmp = dkmp->dkm_next) { 555 if (strcmp(dkmp->dkm_name, name) == 0) 556 return (dkmp); 557 } 558 559 return (NULL); 560} 561#endif 562 563static int 564dt_module_load_sect(dtrace_hdl_t *dtp, dt_module_t *dmp, ctf_sect_t *ctsp) 565{ 566 const char *s; 567 size_t shstrs; 568 GElf_Shdr sh; 569 Elf_Data *dp; 570 Elf_Scn *sp; 571 572 if (elf_getshdrstrndx(dmp->dm_elf, &shstrs) == -1) 573 return (dt_set_errno(dtp, EDT_NOTLOADED)); 574 575 for (sp = NULL; (sp = elf_nextscn(dmp->dm_elf, sp)) != NULL; ) { 576 if (gelf_getshdr(sp, &sh) == NULL || sh.sh_type == SHT_NULL || 577 (s = elf_strptr(dmp->dm_elf, shstrs, sh.sh_name)) == NULL) 578 continue; /* skip any malformed sections */ 579 580 if (sh.sh_type == ctsp->cts_type && 581 sh.sh_entsize == ctsp->cts_entsize && 582 strcmp(s, ctsp->cts_name) == 0) 583 break; /* section matches specification */ 584 } 585 586 /* 587 * If the section isn't found, return success but leave cts_data set 588 * to NULL and cts_size set to zero for our caller. 589 */ 590 if (sp == NULL || (dp = elf_getdata(sp, NULL)) == NULL) 591 return (0); 592 593#ifdef illumos 594 ctsp->cts_data = dp->d_buf; 595#else 596 if ((ctsp->cts_data = malloc(dp->d_size)) == NULL) 597 return (0); 598 memcpy(ctsp->cts_data, dp->d_buf, dp->d_size); 599#endif 600 ctsp->cts_size = dp->d_size; 601 602 dt_dprintf("loaded %s [%s] (%lu bytes)\n", 603 dmp->dm_name, ctsp->cts_name, (ulong_t)ctsp->cts_size); 604 605 return (0); 606} 607 608typedef struct dt_module_cb_arg { 609 struct ps_prochandle *dpa_proc; 610 dtrace_hdl_t *dpa_dtp; 611 dt_module_t *dpa_dmp; 612 uint_t dpa_count; 613} dt_module_cb_arg_t; 614 615/* ARGSUSED */ 616static int 617dt_module_load_proc_count(void *arg, const prmap_t *prmap, const char *obj) 618{ 619 ctf_file_t *fp; 620 dt_module_cb_arg_t *dcp = arg; 621 622 /* Try to grab a ctf container if it exists */ 623 fp = Pname_to_ctf(dcp->dpa_proc, obj); 624 if (fp != NULL) 625 dcp->dpa_count++; 626 return (0); 627} 628 629/* ARGSUSED */ 630static int 631dt_module_load_proc_build(void *arg, const prmap_t *prmap, const char *obj) 632{ 633 ctf_file_t *fp; 634 char buf[MAXPATHLEN], *p; 635 dt_module_cb_arg_t *dcp = arg; 636 int count = dcp->dpa_count; 637 Lmid_t lmid; 638 639 fp = Pname_to_ctf(dcp->dpa_proc, obj); 640 if (fp == NULL) 641 return (0); 642 fp = ctf_dup(fp); 643 if (fp == NULL) 644 return (0); 645 dcp->dpa_dmp->dm_libctfp[count] = fp; 646 /* 647 * While it'd be nice to simply use objname here, because of our prior 648 * actions we'll always get a resolved object name to its on disk file. 649 * Like the pid provider, we need to tell a bit of a lie here. The type 650 * that the user thinks of is in terms of the libraries they requested, 651 * eg. libc.so.1, they don't care about the fact that it's 652 * libc_hwcap.so.1. 653 */ 654 (void) Pobjname(dcp->dpa_proc, prmap->pr_vaddr, buf, sizeof (buf)); 655 if ((p = strrchr(buf, '/')) == NULL) 656 p = buf; 657 else 658 p++; 659 660 /* 661 * If for some reason we can't find a link map id for this module, which 662 * would be really quite weird. We instead just say the link map id is 663 * zero. 664 */ 665 if (Plmid(dcp->dpa_proc, prmap->pr_vaddr, &lmid) != 0) 666 lmid = 0; 667 668 if (lmid == 0) 669 dcp->dpa_dmp->dm_libctfn[count] = strdup(p); 670 else 671 (void) asprintf(&dcp->dpa_dmp->dm_libctfn[count], 672 "LM%x`%s", lmid, p); 673 if (dcp->dpa_dmp->dm_libctfn[count] == NULL) 674 return (1); 675 ctf_setspecific(fp, dcp->dpa_dmp); 676 dcp->dpa_count++; 677 return (0); 678} 679 680/* 681 * We've been asked to load data that belongs to another process. As such we're 682 * going to pgrab it at this instant, load everything that we might ever care 683 * about, and then drive on. The reason for this is that the process that we're 684 * interested in might be changing. As long as we have grabbed it, then this 685 * can't be a problem for us. 686 * 687 * For now, we're actually going to punt on most things and just try to get CTF 688 * data, nothing else. Basically this is only useful as a source of type 689 * information, we can't go and do the stacktrace lookups, etc. 690 */ 691static int 692dt_module_load_proc(dtrace_hdl_t *dtp, dt_module_t *dmp) 693{ 694 struct ps_prochandle *p; 695 dt_module_cb_arg_t arg; 696 697 /* 698 * Note that on success we do not release this hold. We must hold this 699 * for our life time. 700 */ 701 p = dt_proc_grab(dtp, dmp->dm_pid, 0, PGRAB_RDONLY | PGRAB_FORCE); 702 if (p == NULL) { 703 dt_dprintf("failed to grab pid: %d\n", (int)dmp->dm_pid); 704 return (dt_set_errno(dtp, EDT_CANTLOAD)); 705 } 706 dt_proc_lock(dtp, p); 707 708 arg.dpa_proc = p; 709 arg.dpa_dtp = dtp; 710 arg.dpa_dmp = dmp; 711 arg.dpa_count = 0; 712 if (Pobject_iter_resolved(p, dt_module_load_proc_count, &arg) != 0) { 713 dt_dprintf("failed to iterate objects\n"); 714 dt_proc_release(dtp, p); 715 return (dt_set_errno(dtp, EDT_CANTLOAD)); 716 } 717 718 if (arg.dpa_count == 0) { 719 dt_dprintf("no ctf data present\n"); 720 dt_proc_unlock(dtp, p); 721 dt_proc_release(dtp, p); 722 return (dt_set_errno(dtp, EDT_CANTLOAD)); 723 } 724 725 dmp->dm_libctfp = calloc(arg.dpa_count, sizeof (ctf_file_t *)); 726 if (dmp->dm_libctfp == NULL) { 727 dt_proc_unlock(dtp, p); 728 dt_proc_release(dtp, p); 729 return (dt_set_errno(dtp, EDT_NOMEM)); 730 } 731 732 dmp->dm_libctfn = calloc(arg.dpa_count, sizeof (char *)); 733 if (dmp->dm_libctfn == NULL) { 734 free(dmp->dm_libctfp); 735 dt_proc_unlock(dtp, p); 736 dt_proc_release(dtp, p); 737 return (dt_set_errno(dtp, EDT_NOMEM)); 738 } 739 740 dmp->dm_nctflibs = arg.dpa_count; 741 742 arg.dpa_count = 0; 743 if (Pobject_iter_resolved(p, dt_module_load_proc_build, &arg) != 0) { 744 dt_proc_unlock(dtp, p); 745 dt_module_unload(dtp, dmp); 746 dt_proc_release(dtp, p); 747 return (dt_set_errno(dtp, EDT_CANTLOAD)); 748 } 749 assert(arg.dpa_count == dmp->dm_nctflibs); 750 dt_dprintf("loaded %d ctf modules for pid %d\n", arg.dpa_count, 751 (int)dmp->dm_pid); 752 753 dt_proc_unlock(dtp, p); 754 dt_proc_release(dtp, p); 755 dmp->dm_flags |= DT_DM_LOADED; 756 757 return (0); 758} 759 760int 761dt_module_load(dtrace_hdl_t *dtp, dt_module_t *dmp) 762{ 763 if (dmp->dm_flags & DT_DM_LOADED) 764 return (0); /* module is already loaded */ 765 766 if (dmp->dm_pid != 0) 767 return (dt_module_load_proc(dtp, dmp)); 768 769 dmp->dm_ctdata.cts_name = ".SUNW_ctf"; 770 dmp->dm_ctdata.cts_type = SHT_PROGBITS; 771 dmp->dm_ctdata.cts_flags = 0; 772 dmp->dm_ctdata.cts_data = NULL; 773 dmp->dm_ctdata.cts_size = 0; 774 dmp->dm_ctdata.cts_entsize = 0; 775 dmp->dm_ctdata.cts_offset = 0; 776 777 dmp->dm_symtab.cts_name = ".symtab"; 778 dmp->dm_symtab.cts_type = SHT_SYMTAB; 779 dmp->dm_symtab.cts_flags = 0; 780 dmp->dm_symtab.cts_data = NULL; 781 dmp->dm_symtab.cts_size = 0; 782 dmp->dm_symtab.cts_entsize = dmp->dm_ops == &dt_modops_64 ? 783 sizeof (Elf64_Sym) : sizeof (Elf32_Sym); 784 dmp->dm_symtab.cts_offset = 0; 785 786 dmp->dm_strtab.cts_name = ".strtab"; 787 dmp->dm_strtab.cts_type = SHT_STRTAB; 788 dmp->dm_strtab.cts_flags = 0; 789 dmp->dm_strtab.cts_data = NULL; 790 dmp->dm_strtab.cts_size = 0; 791 dmp->dm_strtab.cts_entsize = 0; 792 dmp->dm_strtab.cts_offset = 0; 793 794 /* 795 * Attempt to load the module's CTF section, symbol table section, and 796 * string table section. Note that modules may not contain CTF data: 797 * this will result in a successful load_sect but data of size zero. 798 * We will then fail if dt_module_getctf() is called, as shown below. 799 */ 800 if (dt_module_load_sect(dtp, dmp, &dmp->dm_ctdata) == -1 || 801 dt_module_load_sect(dtp, dmp, &dmp->dm_symtab) == -1 || 802 dt_module_load_sect(dtp, dmp, &dmp->dm_strtab) == -1) { 803 dt_module_unload(dtp, dmp); 804 return (-1); /* dt_errno is set for us */ 805 } 806 807 /* 808 * Allocate the hash chains and hash buckets for symbol name lookup. 809 * This is relatively simple since the symbol table is of fixed size 810 * and is known in advance. We allocate one extra element since we 811 * use element indices instead of pointers and zero is our sentinel. 812 */ 813 dmp->dm_nsymelems = 814 dmp->dm_symtab.cts_size / dmp->dm_symtab.cts_entsize; 815 816 dmp->dm_nsymbuckets = _dtrace_strbuckets; 817 dmp->dm_symfree = 1; /* first free element is index 1 */ 818 819 dmp->dm_symbuckets = calloc(dmp->dm_nsymbuckets, sizeof (uint_t)); 820 dmp->dm_symchains = calloc(dmp->dm_nsymelems + 1, sizeof (dt_sym_t)); 821 822 if (dmp->dm_symbuckets == NULL || dmp->dm_symchains == NULL) { 823 dt_module_unload(dtp, dmp); 824 return (dt_set_errno(dtp, EDT_NOMEM)); 825 } 826 827 /* 828 * Iterate over the symbol table data buffer and insert each symbol 829 * name into the name hash if the name and type are valid. Then 830 * allocate the address map, fill it in, and sort it. 831 */ 832 dmp->dm_asrsv = dmp->dm_ops->do_syminit(dmp); 833 834 dt_dprintf("hashed %s [%s] (%u symbols)\n", 835 dmp->dm_name, dmp->dm_symtab.cts_name, dmp->dm_symfree - 1); 836 837 if ((dmp->dm_asmap = malloc(sizeof (void *) * dmp->dm_asrsv)) == NULL) { 838 dt_module_unload(dtp, dmp); 839 return (dt_set_errno(dtp, EDT_NOMEM)); 840 } 841 842 dmp->dm_ops->do_symsort(dmp); 843 844 dt_dprintf("sorted %s [%s] (%u symbols)\n", 845 dmp->dm_name, dmp->dm_symtab.cts_name, dmp->dm_aslen); 846 847 dmp->dm_flags |= DT_DM_LOADED; 848 return (0); 849} 850 851int 852dt_module_hasctf(dtrace_hdl_t *dtp, dt_module_t *dmp) 853{ 854 if (dmp->dm_pid != 0 && dmp->dm_nctflibs > 0) 855 return (1); 856 return (dt_module_getctf(dtp, dmp) != NULL); 857} 858 859ctf_file_t * 860dt_module_getctf(dtrace_hdl_t *dtp, dt_module_t *dmp) 861{ 862 const char *parent; 863 dt_module_t *pmp; 864 ctf_file_t *pfp; 865 int model; 866 867 if (dmp->dm_ctfp != NULL || dt_module_load(dtp, dmp) != 0) 868 return (dmp->dm_ctfp); 869 870 if (dmp->dm_ops == &dt_modops_64) 871 model = CTF_MODEL_LP64; 872 else 873 model = CTF_MODEL_ILP32; 874 875 /* 876 * If the data model of the module does not match our program data 877 * model, then do not permit CTF from this module to be opened and 878 * returned to the compiler. If we support mixed data models in the 879 * future for combined kernel/user tracing, this can be removed. 880 */ 881 if (dtp->dt_conf.dtc_ctfmodel != model) { 882 (void) dt_set_errno(dtp, EDT_DATAMODEL); 883 return (NULL); 884 } 885 886 if (dmp->dm_ctdata.cts_size == 0) { 887 (void) dt_set_errno(dtp, EDT_NOCTF); 888 return (NULL); 889 } 890 891 dmp->dm_ctfp = ctf_bufopen(&dmp->dm_ctdata, 892 &dmp->dm_symtab, &dmp->dm_strtab, &dtp->dt_ctferr); 893 894 if (dmp->dm_ctfp == NULL) { 895 (void) dt_set_errno(dtp, EDT_CTF); 896 return (NULL); 897 } 898 899 (void) ctf_setmodel(dmp->dm_ctfp, model); 900 ctf_setspecific(dmp->dm_ctfp, dmp); 901 902 if ((parent = ctf_parent_name(dmp->dm_ctfp)) != NULL) { 903 if ((pmp = dt_module_create(dtp, parent)) == NULL || 904 (pfp = dt_module_getctf(dtp, pmp)) == NULL) { 905 if (pmp == NULL) 906 (void) dt_set_errno(dtp, EDT_NOMEM); 907 goto err; 908 } 909 910 if (ctf_import(dmp->dm_ctfp, pfp) == CTF_ERR) { 911 dtp->dt_ctferr = ctf_errno(dmp->dm_ctfp); 912 (void) dt_set_errno(dtp, EDT_CTF); 913 goto err; 914 } 915 } 916 917 dt_dprintf("loaded CTF container for %s (%p)\n", 918 dmp->dm_name, (void *)dmp->dm_ctfp); 919 920 return (dmp->dm_ctfp); 921 922err: 923 ctf_close(dmp->dm_ctfp); 924 dmp->dm_ctfp = NULL; 925 return (NULL); 926} 927 928/*ARGSUSED*/ 929void 930dt_module_unload(dtrace_hdl_t *dtp, dt_module_t *dmp) 931{ 932 int i; 933 934 ctf_close(dmp->dm_ctfp); 935 dmp->dm_ctfp = NULL; 936 937#ifndef illumos 938 if (dmp->dm_ctdata.cts_data != NULL) { 939 free(dmp->dm_ctdata.cts_data); 940 } 941 if (dmp->dm_symtab.cts_data != NULL) { 942 free(dmp->dm_symtab.cts_data); 943 } 944 if (dmp->dm_strtab.cts_data != NULL) { 945 free(dmp->dm_strtab.cts_data); 946 } 947#endif 948 949 if (dmp->dm_libctfp != NULL) { 950 for (i = 0; i < dmp->dm_nctflibs; i++) { 951 ctf_close(dmp->dm_libctfp[i]); 952 free(dmp->dm_libctfn[i]); 953 } 954 free(dmp->dm_libctfp); 955 free(dmp->dm_libctfn); 956 dmp->dm_libctfp = NULL; 957 dmp->dm_nctflibs = 0; 958 } 959 960 bzero(&dmp->dm_ctdata, sizeof (ctf_sect_t)); 961 bzero(&dmp->dm_symtab, sizeof (ctf_sect_t)); 962 bzero(&dmp->dm_strtab, sizeof (ctf_sect_t)); 963 964 if (dmp->dm_symbuckets != NULL) { 965 free(dmp->dm_symbuckets); 966 dmp->dm_symbuckets = NULL; 967 } 968 969 if (dmp->dm_symchains != NULL) { 970 free(dmp->dm_symchains); 971 dmp->dm_symchains = NULL; 972 } 973 974 if (dmp->dm_asmap != NULL) { 975 free(dmp->dm_asmap); 976 dmp->dm_asmap = NULL; 977 } 978#if defined(__FreeBSD__) 979 if (dmp->dm_sec_offsets != NULL) { 980 free(dmp->dm_sec_offsets); 981 dmp->dm_sec_offsets = NULL; 982 } 983#endif 984 dmp->dm_symfree = 0; 985 dmp->dm_nsymbuckets = 0; 986 dmp->dm_nsymelems = 0; 987 dmp->dm_asrsv = 0; 988 dmp->dm_aslen = 0; 989 990 dmp->dm_text_va = 0; 991 dmp->dm_text_size = 0; 992 dmp->dm_data_va = 0; 993 dmp->dm_data_size = 0; 994 dmp->dm_bss_va = 0; 995 dmp->dm_bss_size = 0; 996 997 if (dmp->dm_extern != NULL) { 998 dt_idhash_destroy(dmp->dm_extern); 999 dmp->dm_extern = NULL; 1000 } 1001 1002 (void) elf_end(dmp->dm_elf); 1003 dmp->dm_elf = NULL; 1004 1005 dmp->dm_pid = 0; 1006 1007 dmp->dm_flags &= ~DT_DM_LOADED; 1008} 1009 1010void 1011dt_module_destroy(dtrace_hdl_t *dtp, dt_module_t *dmp) 1012{ 1013 uint_t h = dt_strtab_hash(dmp->dm_name, NULL) % dtp->dt_modbuckets; 1014 dt_module_t **dmpp = &dtp->dt_mods[h]; 1015 1016 dt_list_delete(&dtp->dt_modlist, dmp); 1017 assert(dtp->dt_nmods != 0); 1018 dtp->dt_nmods--; 1019 1020 /* 1021 * Now remove this module from its hash chain. We expect to always 1022 * find the module on its hash chain, so in this loop we assert that 1023 * we don't run off the end of the list. 1024 */ 1025 while (*dmpp != dmp) { 1026 dmpp = &((*dmpp)->dm_next); 1027 assert(*dmpp != NULL); 1028 } 1029 1030 *dmpp = dmp->dm_next; 1031 1032 dt_module_unload(dtp, dmp); 1033 free(dmp); 1034} 1035 1036/* 1037 * Insert a new external symbol reference into the specified module. The new 1038 * symbol will be marked as undefined and is assigned a symbol index beyond 1039 * any existing cached symbols from this module. We use the ident's di_data 1040 * field to store a pointer to a copy of the dtrace_syminfo_t for this symbol. 1041 */ 1042dt_ident_t * 1043dt_module_extern(dtrace_hdl_t *dtp, dt_module_t *dmp, 1044 const char *name, const dtrace_typeinfo_t *tip) 1045{ 1046 dtrace_syminfo_t *sip; 1047 dt_ident_t *idp; 1048 uint_t id; 1049 1050 if (dmp->dm_extern == NULL && (dmp->dm_extern = dt_idhash_create( 1051 "extern", NULL, dmp->dm_nsymelems, UINT_MAX)) == NULL) { 1052 (void) dt_set_errno(dtp, EDT_NOMEM); 1053 return (NULL); 1054 } 1055 1056 if (dt_idhash_nextid(dmp->dm_extern, &id) == -1) { 1057 (void) dt_set_errno(dtp, EDT_SYMOFLOW); 1058 return (NULL); 1059 } 1060 1061 if ((sip = malloc(sizeof (dtrace_syminfo_t))) == NULL) { 1062 (void) dt_set_errno(dtp, EDT_NOMEM); 1063 return (NULL); 1064 } 1065 1066 idp = dt_idhash_insert(dmp->dm_extern, name, DT_IDENT_SYMBOL, 0, id, 1067 _dtrace_symattr, 0, &dt_idops_thaw, NULL, dtp->dt_gen); 1068 1069 if (idp == NULL) { 1070 (void) dt_set_errno(dtp, EDT_NOMEM); 1071 free(sip); 1072 return (NULL); 1073 } 1074 1075 sip->dts_object = dmp->dm_name; 1076 sip->dts_name = idp->di_name; 1077 sip->dts_id = idp->di_id; 1078 1079 idp->di_data = sip; 1080 idp->di_ctfp = tip->dtt_ctfp; 1081 idp->di_type = tip->dtt_type; 1082 1083 return (idp); 1084} 1085 1086const char * 1087dt_module_modelname(dt_module_t *dmp) 1088{ 1089 if (dmp->dm_ops == &dt_modops_64) 1090 return ("64-bit"); 1091 else 1092 return ("32-bit"); 1093} 1094 1095/* ARGSUSED */ 1096int 1097dt_module_getlibid(dtrace_hdl_t *dtp, dt_module_t *dmp, const ctf_file_t *fp) 1098{ 1099 int i; 1100 1101 for (i = 0; i < dmp->dm_nctflibs; i++) { 1102 if (dmp->dm_libctfp[i] == fp) 1103 return (i); 1104 } 1105 1106 return (-1); 1107} 1108 1109/* ARGSUSED */ 1110ctf_file_t * 1111dt_module_getctflib(dtrace_hdl_t *dtp, dt_module_t *dmp, const char *name) 1112{ 1113 int i; 1114 1115 for (i = 0; i < dmp->dm_nctflibs; i++) { 1116 if (strcmp(dmp->dm_libctfn[i], name) == 0) 1117 return (dmp->dm_libctfp[i]); 1118 } 1119 1120 return (NULL); 1121} 1122 1123/* 1124 * Update our module cache by adding an entry for the specified module 'name'. 1125 * We create the dt_module_t and populate it using /system/object/<name>/. 1126 * 1127 * On FreeBSD, the module name is passed as the full module file name, 1128 * including the path. 1129 */ 1130static void 1131#ifdef illumos 1132dt_module_update(dtrace_hdl_t *dtp, const char *name) 1133#else 1134dt_module_update(dtrace_hdl_t *dtp, struct kld_file_stat *k_stat) 1135#endif 1136{ 1137 char fname[MAXPATHLEN]; 1138 struct stat64 st; 1139 int fd, err, bits; 1140#ifdef __FreeBSD__ 1141 struct module_stat ms; 1142 dt_kmodule_t *dkmp; 1143 uint_t h; 1144 int modid; 1145#endif 1146 1147 dt_module_t *dmp; 1148 const char *s; 1149 size_t shstrs; 1150 GElf_Shdr sh; 1151 Elf_Data *dp; 1152 Elf_Scn *sp; 1153 1154#ifdef illumos 1155 (void) snprintf(fname, sizeof (fname), 1156 "%s/%s/object", OBJFS_ROOT, name); 1157#else 1158 GElf_Ehdr ehdr; 1159 GElf_Phdr ph; 1160 char name[MAXPATHLEN]; 1161 uintptr_t mapbase, alignmask; 1162 int i = 0; 1163 int is_elf_obj; 1164 1165 (void) strlcpy(name, k_stat->name, sizeof(name)); 1166 (void) strlcpy(fname, k_stat->pathname, sizeof(fname)); 1167#endif 1168 1169 if ((fd = open(fname, O_RDONLY)) == -1 || fstat64(fd, &st) == -1 || 1170 (dmp = dt_module_create(dtp, name)) == NULL) { 1171 dt_dprintf("failed to open %s: %s\n", fname, strerror(errno)); 1172 (void) close(fd); 1173 return; 1174 } 1175 1176 /* 1177 * Since the module can unload out from under us (and /system/object 1178 * will return ENOENT), tell libelf to cook the entire file now and 1179 * then close the underlying file descriptor immediately. If this 1180 * succeeds, we know that we can continue safely using dmp->dm_elf. 1181 */ 1182 dmp->dm_elf = elf_begin(fd, ELF_C_READ, NULL); 1183 err = elf_cntl(dmp->dm_elf, ELF_C_FDREAD); 1184 (void) close(fd); 1185 1186 if (dmp->dm_elf == NULL || err == -1 || 1187 elf_getshdrstrndx(dmp->dm_elf, &shstrs) == -1) { 1188 dt_dprintf("failed to load %s: %s\n", 1189 fname, elf_errmsg(elf_errno())); 1190 dt_module_destroy(dtp, dmp); 1191 return; 1192 } 1193 1194 switch (gelf_getclass(dmp->dm_elf)) { 1195 case ELFCLASS32: 1196 dmp->dm_ops = &dt_modops_32; 1197 bits = 32; 1198 break; 1199 case ELFCLASS64: 1200 dmp->dm_ops = &dt_modops_64; 1201 bits = 64; 1202 break; 1203 default: 1204 dt_dprintf("failed to load %s: unknown ELF class\n", fname); 1205 dt_module_destroy(dtp, dmp); 1206 return; 1207 } 1208#if defined(__FreeBSD__) 1209 mapbase = (uintptr_t)k_stat->address; 1210 gelf_getehdr(dmp->dm_elf, &ehdr); 1211 is_elf_obj = (ehdr.e_type == ET_REL); 1212 if (is_elf_obj) { 1213 dmp->dm_sec_offsets = 1214 malloc(ehdr.e_shnum * sizeof(*dmp->dm_sec_offsets)); 1215 if (dmp->dm_sec_offsets == NULL) { 1216 dt_dprintf("failed to allocate memory\n"); 1217 dt_module_destroy(dtp, dmp); 1218 return; 1219 } 1220 } 1221#endif 1222 /* 1223 * Iterate over the section headers locating various sections of 1224 * interest and use their attributes to flesh out the dt_module_t. 1225 */ 1226 for (sp = NULL; (sp = elf_nextscn(dmp->dm_elf, sp)) != NULL; ) { 1227 if (gelf_getshdr(sp, &sh) == NULL || sh.sh_type == SHT_NULL || 1228 (s = elf_strptr(dmp->dm_elf, shstrs, sh.sh_name)) == NULL) 1229 continue; /* skip any malformed sections */ 1230#if defined(__FreeBSD__) 1231 if (sh.sh_size == 0) 1232 continue; 1233 if (sh.sh_type == SHT_PROGBITS || sh.sh_type == SHT_NOBITS) { 1234 alignmask = sh.sh_addralign - 1; 1235 mapbase += alignmask; 1236 mapbase &= ~alignmask; 1237 sh.sh_addr = mapbase; 1238 if (is_elf_obj) 1239 dmp->dm_sec_offsets[elf_ndxscn(sp)] = sh.sh_addr; 1240 mapbase += sh.sh_size; 1241 } 1242#endif 1243 if (strcmp(s, ".text") == 0) { 1244 dmp->dm_text_size = sh.sh_size; 1245 dmp->dm_text_va = sh.sh_addr; 1246 } else if (strcmp(s, ".data") == 0) { 1247 dmp->dm_data_size = sh.sh_size; 1248 dmp->dm_data_va = sh.sh_addr; 1249 } else if (strcmp(s, ".bss") == 0) { 1250 dmp->dm_bss_size = sh.sh_size; 1251 dmp->dm_bss_va = sh.sh_addr; 1252 } else if (strcmp(s, ".info") == 0 && 1253 (dp = elf_getdata(sp, NULL)) != NULL) { 1254 bcopy(dp->d_buf, &dmp->dm_info, 1255 MIN(sh.sh_size, sizeof (dmp->dm_info))); 1256 } else if (strcmp(s, ".filename") == 0 && 1257 (dp = elf_getdata(sp, NULL)) != NULL) { 1258 (void) strlcpy(dmp->dm_file, 1259 dp->d_buf, sizeof (dmp->dm_file)); 1260 } 1261 } 1262 1263 dmp->dm_flags |= DT_DM_KERNEL; 1264#ifdef illumos 1265 dmp->dm_modid = (int)OBJFS_MODID(st.st_ino); 1266#else 1267 /* 1268 * Include .rodata and special sections into .text. 1269 * This depends on default section layout produced by GNU ld 1270 * for ELF objects and libraries: 1271 * [Text][R/O data][R/W data][Dynamic][BSS][Non loadable] 1272 */ 1273 dmp->dm_text_size = dmp->dm_data_va - dmp->dm_text_va; 1274#if defined(__i386__) 1275 /* 1276 * Find the first load section and figure out the relocation 1277 * offset for the symbols. The kernel module will not need 1278 * relocation, but the kernel linker modules will. 1279 */ 1280 for (i = 0; gelf_getphdr(dmp->dm_elf, i, &ph) != NULL; i++) { 1281 if (ph.p_type == PT_LOAD) { 1282 dmp->dm_reloc_offset = k_stat->address - ph.p_vaddr; 1283 break; 1284 } 1285 } 1286#endif 1287#endif /* illumos */ 1288 1289 if (dmp->dm_info.objfs_info_primary) 1290 dmp->dm_flags |= DT_DM_PRIMARY; 1291 1292#ifdef __FreeBSD__ 1293 ms.version = sizeof(ms); 1294 for (modid = kldfirstmod(k_stat->id); modid > 0; 1295 modid = modnext(modid)) { 1296 if (modstat(modid, &ms) != 0) { 1297 dt_dprintf("modstat failed for id %d in %s: %s\n", 1298 modid, k_stat->name, strerror(errno)); 1299 continue; 1300 } 1301 if (dt_kmodule_lookup(dtp, ms.name) != NULL) 1302 continue; 1303 1304 dkmp = malloc(sizeof (*dkmp)); 1305 if (dkmp == NULL) { 1306 dt_dprintf("failed to allocate memory\n"); 1307 dt_module_destroy(dtp, dmp); 1308 return; 1309 } 1310 1311 h = dt_strtab_hash(ms.name, NULL) % dtp->dt_modbuckets; 1312 dkmp->dkm_next = dtp->dt_kmods[h]; 1313 dkmp->dkm_name = strdup(ms.name); 1314 dkmp->dkm_module = dmp; 1315 dtp->dt_kmods[h] = dkmp; 1316 } 1317#endif 1318 1319 dt_dprintf("opened %d-bit module %s (%s) [%d]\n", 1320 bits, dmp->dm_name, dmp->dm_file, dmp->dm_modid); 1321} 1322 1323/* 1324 * Unload all the loaded modules and then refresh the module cache with the 1325 * latest list of loaded modules and their address ranges. 1326 */ 1327void 1328dtrace_update(dtrace_hdl_t *dtp) 1329{ 1330 dt_module_t *dmp; 1331 DIR *dirp; 1332#if defined(__FreeBSD__) 1333 int fileid; 1334#endif 1335 1336 for (dmp = dt_list_next(&dtp->dt_modlist); 1337 dmp != NULL; dmp = dt_list_next(dmp)) 1338 dt_module_unload(dtp, dmp); 1339 1340#ifdef illumos 1341 /* 1342 * Open /system/object and attempt to create a libdtrace module for 1343 * each kernel module that is loaded on the current system. 1344 */ 1345 if (!(dtp->dt_oflags & DTRACE_O_NOSYS) && 1346 (dirp = opendir(OBJFS_ROOT)) != NULL) { 1347 struct dirent *dp; 1348 1349 while ((dp = readdir(dirp)) != NULL) { 1350 if (dp->d_name[0] != '.') 1351 dt_module_update(dtp, dp->d_name); 1352 } 1353 1354 (void) closedir(dirp); 1355 } 1356#elif defined(__FreeBSD__) 1357 /* 1358 * Use FreeBSD's kernel loader interface to discover what kernel 1359 * modules are loaded and create a libdtrace module for each one. 1360 */ 1361 for (fileid = kldnext(0); fileid > 0; fileid = kldnext(fileid)) { 1362 struct kld_file_stat k_stat; 1363 k_stat.version = sizeof(k_stat); 1364 if (kldstat(fileid, &k_stat) == 0) 1365 dt_module_update(dtp, &k_stat); 1366 } 1367#endif 1368 1369 /* 1370 * Look up all the macro identifiers and set di_id to the latest value. 1371 * This code collaborates with dt_lex.l on the use of di_id. We will 1372 * need to implement something fancier if we need to support non-ints. 1373 */ 1374 dt_idhash_lookup(dtp->dt_macros, "egid")->di_id = getegid(); 1375 dt_idhash_lookup(dtp->dt_macros, "euid")->di_id = geteuid(); 1376 dt_idhash_lookup(dtp->dt_macros, "gid")->di_id = getgid(); 1377 dt_idhash_lookup(dtp->dt_macros, "pid")->di_id = getpid(); 1378 dt_idhash_lookup(dtp->dt_macros, "pgid")->di_id = getpgid(0); 1379 dt_idhash_lookup(dtp->dt_macros, "ppid")->di_id = getppid(); 1380#ifdef illumos 1381 dt_idhash_lookup(dtp->dt_macros, "projid")->di_id = getprojid(); 1382#endif 1383 dt_idhash_lookup(dtp->dt_macros, "sid")->di_id = getsid(0); 1384#ifdef illumos 1385 dt_idhash_lookup(dtp->dt_macros, "taskid")->di_id = gettaskid(); 1386#endif 1387 dt_idhash_lookup(dtp->dt_macros, "uid")->di_id = getuid(); 1388 1389 /* 1390 * Cache the pointers to the modules representing the base executable 1391 * and the run-time linker in the dtrace client handle. Note that on 1392 * x86 krtld is folded into unix, so if we don't find it, use unix 1393 * instead. 1394 */ 1395 dtp->dt_exec = dt_module_lookup_by_name(dtp, "genunix"); 1396 dtp->dt_rtld = dt_module_lookup_by_name(dtp, "krtld"); 1397 if (dtp->dt_rtld == NULL) 1398 dtp->dt_rtld = dt_module_lookup_by_name(dtp, "unix"); 1399 1400 /* 1401 * If this is the first time we are initializing the module list, 1402 * remove the module for genunix from the module list and then move it 1403 * to the front of the module list. We do this so that type and symbol 1404 * queries encounter genunix and thereby optimize for the common case 1405 * in dtrace_lookup_by_name() and dtrace_lookup_by_type(), below. 1406 */ 1407 if (dtp->dt_exec != NULL && 1408 dtp->dt_cdefs == NULL && dtp->dt_ddefs == NULL) { 1409 dt_list_delete(&dtp->dt_modlist, dtp->dt_exec); 1410 dt_list_prepend(&dtp->dt_modlist, dtp->dt_exec); 1411 } 1412} 1413 1414static dt_module_t * 1415dt_module_from_object(dtrace_hdl_t *dtp, const char *object) 1416{ 1417 int err = EDT_NOMOD; 1418 dt_module_t *dmp; 1419 1420 switch ((uintptr_t)object) { 1421 case (uintptr_t)DTRACE_OBJ_EXEC: 1422 dmp = dtp->dt_exec; 1423 break; 1424 case (uintptr_t)DTRACE_OBJ_RTLD: 1425 dmp = dtp->dt_rtld; 1426 break; 1427 case (uintptr_t)DTRACE_OBJ_CDEFS: 1428 dmp = dtp->dt_cdefs; 1429 break; 1430 case (uintptr_t)DTRACE_OBJ_DDEFS: 1431 dmp = dtp->dt_ddefs; 1432 break; 1433 default: 1434 dmp = dt_module_create(dtp, object); 1435 err = EDT_NOMEM; 1436 } 1437 1438 if (dmp == NULL) 1439 (void) dt_set_errno(dtp, err); 1440 1441 return (dmp); 1442} 1443 1444/* 1445 * Exported interface to look up a symbol by name. We return the GElf_Sym and 1446 * complete symbol information for the matching symbol. 1447 */ 1448int 1449dtrace_lookup_by_name(dtrace_hdl_t *dtp, const char *object, const char *name, 1450 GElf_Sym *symp, dtrace_syminfo_t *sip) 1451{ 1452 dt_module_t *dmp; 1453 dt_ident_t *idp; 1454 uint_t n, id; 1455 GElf_Sym sym; 1456 1457 uint_t mask = 0; /* mask of dt_module flags to match */ 1458 uint_t bits = 0; /* flag bits that must be present */ 1459 1460 if (object != DTRACE_OBJ_EVERY && 1461 object != DTRACE_OBJ_KMODS && 1462 object != DTRACE_OBJ_UMODS) { 1463 if ((dmp = dt_module_from_object(dtp, object)) == NULL) 1464 return (-1); /* dt_errno is set for us */ 1465 1466 if (dt_module_load(dtp, dmp) == -1) 1467 return (-1); /* dt_errno is set for us */ 1468 n = 1; 1469 1470 } else { 1471 if (object == DTRACE_OBJ_KMODS) 1472 mask = bits = DT_DM_KERNEL; 1473 else if (object == DTRACE_OBJ_UMODS) 1474 mask = DT_DM_KERNEL; 1475 1476 dmp = dt_list_next(&dtp->dt_modlist); 1477 n = dtp->dt_nmods; 1478 } 1479 1480 if (symp == NULL) 1481 symp = &sym; 1482 1483 for (; n > 0; n--, dmp = dt_list_next(dmp)) { 1484 if ((dmp->dm_flags & mask) != bits) 1485 continue; /* failed to match required attributes */ 1486 1487 if (dt_module_load(dtp, dmp) == -1) 1488 continue; /* failed to load symbol table */ 1489 1490 if (dmp->dm_ops->do_symname(dmp, name, symp, &id) != NULL) { 1491 if (sip != NULL) { 1492 sip->dts_object = dmp->dm_name; 1493 sip->dts_name = (const char *) 1494 dmp->dm_strtab.cts_data + symp->st_name; 1495 sip->dts_id = id; 1496 } 1497 return (0); 1498 } 1499 1500 if (dmp->dm_extern != NULL && 1501 (idp = dt_idhash_lookup(dmp->dm_extern, name)) != NULL) { 1502 if (symp != &sym) { 1503 symp->st_name = (uintptr_t)idp->di_name; 1504 symp->st_info = 1505 GELF_ST_INFO(STB_GLOBAL, STT_NOTYPE); 1506 symp->st_other = 0; 1507 symp->st_shndx = SHN_UNDEF; 1508 symp->st_value = 0; 1509 symp->st_size = 1510 ctf_type_size(idp->di_ctfp, idp->di_type); 1511 } 1512 1513 if (sip != NULL) { 1514 sip->dts_object = dmp->dm_name; 1515 sip->dts_name = idp->di_name; 1516 sip->dts_id = idp->di_id; 1517 } 1518 1519 return (0); 1520 } 1521 } 1522 1523 return (dt_set_errno(dtp, EDT_NOSYM)); 1524} 1525 1526/* 1527 * Exported interface to look up a symbol by address. We return the GElf_Sym 1528 * and complete symbol information for the matching symbol. 1529 */ 1530int 1531dtrace_lookup_by_addr(dtrace_hdl_t *dtp, GElf_Addr addr, 1532 GElf_Sym *symp, dtrace_syminfo_t *sip) 1533{ 1534 dt_module_t *dmp; 1535 uint_t id; 1536 const dtrace_vector_t *v = dtp->dt_vector; 1537 1538 if (v != NULL) 1539 return (v->dtv_lookup_by_addr(dtp->dt_varg, addr, symp, sip)); 1540 1541 for (dmp = dt_list_next(&dtp->dt_modlist); dmp != NULL; 1542 dmp = dt_list_next(dmp)) { 1543 if (addr - dmp->dm_text_va < dmp->dm_text_size || 1544 addr - dmp->dm_data_va < dmp->dm_data_size || 1545 addr - dmp->dm_bss_va < dmp->dm_bss_size) 1546 break; 1547 } 1548 1549 if (dmp == NULL) 1550 return (dt_set_errno(dtp, EDT_NOSYMADDR)); 1551 1552 if (dt_module_load(dtp, dmp) == -1) 1553 return (-1); /* dt_errno is set for us */ 1554 1555 if (symp != NULL) { 1556 if (dmp->dm_ops->do_symaddr(dmp, addr, symp, &id) == NULL) 1557 return (dt_set_errno(dtp, EDT_NOSYMADDR)); 1558 } 1559 1560 if (sip != NULL) { 1561 sip->dts_object = dmp->dm_name; 1562 1563 if (symp != NULL) { 1564 sip->dts_name = (const char *) 1565 dmp->dm_strtab.cts_data + symp->st_name; 1566 sip->dts_id = id; 1567 } else { 1568 sip->dts_name = NULL; 1569 sip->dts_id = 0; 1570 } 1571 } 1572 1573 return (0); 1574} 1575 1576int 1577dtrace_lookup_by_type(dtrace_hdl_t *dtp, const char *object, const char *name, 1578 dtrace_typeinfo_t *tip) 1579{ 1580 dtrace_typeinfo_t ti; 1581 dt_module_t *dmp; 1582 int found = 0; 1583 ctf_id_t id; 1584 uint_t n, i; 1585 int justone; 1586 ctf_file_t *fp; 1587 char *buf, *p, *q; 1588 1589 uint_t mask = 0; /* mask of dt_module flags to match */ 1590 uint_t bits = 0; /* flag bits that must be present */ 1591 1592 if (object != DTRACE_OBJ_EVERY && 1593 object != DTRACE_OBJ_KMODS && 1594 object != DTRACE_OBJ_UMODS) { 1595 if ((dmp = dt_module_from_object(dtp, object)) == NULL) 1596 return (-1); /* dt_errno is set for us */ 1597 1598 if (dt_module_load(dtp, dmp) == -1) 1599 return (-1); /* dt_errno is set for us */ 1600 n = 1; 1601 justone = 1; 1602 } else { 1603 if (object == DTRACE_OBJ_KMODS) 1604 mask = bits = DT_DM_KERNEL; 1605 else if (object == DTRACE_OBJ_UMODS) 1606 mask = DT_DM_KERNEL; 1607 1608 dmp = dt_list_next(&dtp->dt_modlist); 1609 n = dtp->dt_nmods; 1610 justone = 0; 1611 } 1612 1613 if (tip == NULL) 1614 tip = &ti; 1615 1616 for (; n > 0; n--, dmp = dt_list_next(dmp)) { 1617 if ((dmp->dm_flags & mask) != bits) 1618 continue; /* failed to match required attributes */ 1619 1620 /* 1621 * If we can't load the CTF container, continue on to the next 1622 * module. If our search was scoped to only one module then 1623 * return immediately leaving dt_errno unmodified. 1624 */ 1625 if (dt_module_hasctf(dtp, dmp) == 0) { 1626 if (justone) 1627 return (-1); 1628 continue; 1629 } 1630 1631 /* 1632 * Look up the type in the module's CTF container. If our 1633 * match is a forward declaration tag, save this choice in 1634 * 'tip' and keep going in the hope that we will locate the 1635 * underlying structure definition. Otherwise just return. 1636 */ 1637 if (dmp->dm_pid == 0) { 1638 id = ctf_lookup_by_name(dmp->dm_ctfp, name); 1639 fp = dmp->dm_ctfp; 1640 } else { 1641 if ((p = strchr(name, '`')) != NULL) { 1642 buf = strdup(name); 1643 if (buf == NULL) 1644 return (dt_set_errno(dtp, EDT_NOMEM)); 1645 p = strchr(buf, '`'); 1646 if ((q = strchr(p + 1, '`')) != NULL) 1647 p = q; 1648 *p = '\0'; 1649 fp = dt_module_getctflib(dtp, dmp, buf); 1650 if (fp == NULL || (id = ctf_lookup_by_name(fp, 1651 p + 1)) == CTF_ERR) 1652 id = CTF_ERR; 1653 free(buf); 1654 } else { 1655 for (i = 0; i < dmp->dm_nctflibs; i++) { 1656 fp = dmp->dm_libctfp[i]; 1657 id = ctf_lookup_by_name(fp, name); 1658 if (id != CTF_ERR) 1659 break; 1660 } 1661 } 1662 } 1663 if (id != CTF_ERR) { 1664 tip->dtt_object = dmp->dm_name; 1665 tip->dtt_ctfp = fp; 1666 tip->dtt_type = id; 1667 if (ctf_type_kind(fp, ctf_type_resolve(fp, id)) != 1668 CTF_K_FORWARD) 1669 return (0); 1670 1671 found++; 1672 } 1673 } 1674 1675 if (found == 0) 1676 return (dt_set_errno(dtp, EDT_NOTYPE)); 1677 1678 return (0); 1679} 1680 1681int 1682dtrace_symbol_type(dtrace_hdl_t *dtp, const GElf_Sym *symp, 1683 const dtrace_syminfo_t *sip, dtrace_typeinfo_t *tip) 1684{ 1685 dt_module_t *dmp; 1686 1687 tip->dtt_object = NULL; 1688 tip->dtt_ctfp = NULL; 1689 tip->dtt_type = CTF_ERR; 1690 tip->dtt_flags = 0; 1691 1692 if ((dmp = dt_module_lookup_by_name(dtp, sip->dts_object)) == NULL) 1693 return (dt_set_errno(dtp, EDT_NOMOD)); 1694 1695 if (symp->st_shndx == SHN_UNDEF && dmp->dm_extern != NULL) { 1696 dt_ident_t *idp = 1697 dt_idhash_lookup(dmp->dm_extern, sip->dts_name); 1698 1699 if (idp == NULL) 1700 return (dt_set_errno(dtp, EDT_NOSYM)); 1701 1702 tip->dtt_ctfp = idp->di_ctfp; 1703 tip->dtt_type = idp->di_type; 1704 1705 } else if (GELF_ST_TYPE(symp->st_info) != STT_FUNC) { 1706 if (dt_module_getctf(dtp, dmp) == NULL) 1707 return (-1); /* errno is set for us */ 1708 1709 tip->dtt_ctfp = dmp->dm_ctfp; 1710 tip->dtt_type = ctf_lookup_by_symbol(dmp->dm_ctfp, sip->dts_id); 1711 1712 if (tip->dtt_type == CTF_ERR) { 1713 dtp->dt_ctferr = ctf_errno(tip->dtt_ctfp); 1714 return (dt_set_errno(dtp, EDT_CTF)); 1715 } 1716 1717 } else { 1718 tip->dtt_ctfp = DT_FPTR_CTFP(dtp); 1719 tip->dtt_type = DT_FPTR_TYPE(dtp); 1720 } 1721 1722 tip->dtt_object = dmp->dm_name; 1723 return (0); 1724} 1725 1726static dtrace_objinfo_t * 1727dt_module_info(const dt_module_t *dmp, dtrace_objinfo_t *dto) 1728{ 1729 dto->dto_name = dmp->dm_name; 1730 dto->dto_file = dmp->dm_file; 1731 dto->dto_id = dmp->dm_modid; 1732 dto->dto_flags = 0; 1733 1734 if (dmp->dm_flags & DT_DM_KERNEL) 1735 dto->dto_flags |= DTRACE_OBJ_F_KERNEL; 1736 if (dmp->dm_flags & DT_DM_PRIMARY) 1737 dto->dto_flags |= DTRACE_OBJ_F_PRIMARY; 1738 1739 dto->dto_text_va = dmp->dm_text_va; 1740 dto->dto_text_size = dmp->dm_text_size; 1741 dto->dto_data_va = dmp->dm_data_va; 1742 dto->dto_data_size = dmp->dm_data_size; 1743 dto->dto_bss_va = dmp->dm_bss_va; 1744 dto->dto_bss_size = dmp->dm_bss_size; 1745 1746 return (dto); 1747} 1748 1749int 1750dtrace_object_iter(dtrace_hdl_t *dtp, dtrace_obj_f *func, void *data) 1751{ 1752 const dt_module_t *dmp = dt_list_next(&dtp->dt_modlist); 1753 dtrace_objinfo_t dto; 1754 int rv; 1755 1756 for (; dmp != NULL; dmp = dt_list_next(dmp)) { 1757 if ((rv = (*func)(dtp, dt_module_info(dmp, &dto), data)) != 0) 1758 return (rv); 1759 } 1760 1761 return (0); 1762} 1763 1764int 1765dtrace_object_info(dtrace_hdl_t *dtp, const char *object, dtrace_objinfo_t *dto) 1766{ 1767 dt_module_t *dmp; 1768 1769 if (object == DTRACE_OBJ_EVERY || object == DTRACE_OBJ_KMODS || 1770 object == DTRACE_OBJ_UMODS || dto == NULL) 1771 return (dt_set_errno(dtp, EINVAL)); 1772 1773 if ((dmp = dt_module_from_object(dtp, object)) == NULL) 1774 return (-1); /* dt_errno is set for us */ 1775 1776 if (dt_module_load(dtp, dmp) == -1) 1777 return (-1); /* dt_errno is set for us */ 1778 1779 (void) dt_module_info(dmp, dto); 1780 return (0); 1781} 1782