1 /* 2 * Copyright (c) 2003, 2013, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 * 23 */ 24 25 #include <jni.h> 26 #include <unistd.h> 27 #include <fcntl.h> 28 #include <string.h> 29 #include <stdlib.h> 30 #include <stddef.h> 31 #include "libproc_impl.h" 32 33 #ifdef __APPLE__ 34 #include "sun_jvm_hotspot_debugger_amd64_AMD64ThreadContext.h" 35 #endif 36 37 // This file has the libproc implementation to read core files. 38 // For live processes, refer to ps_proc.c. Portions of this is adapted 39 // /modelled after Solaris libproc.so (in particular Pcore.c) 40 41 //---------------------------------------------------------------------- 42 // ps_prochandle cleanup helper functions 43 44 // close all file descriptors 45 static void close_files(struct ps_prochandle* ph) { 46 lib_info* lib = NULL; 47 // close core file descriptor 48 if (ph->core->core_fd >= 0) 49 close(ph->core->core_fd); 50 51 // close exec file descriptor 52 if (ph->core->exec_fd >= 0) 53 close(ph->core->exec_fd); 54 55 // close interp file descriptor 56 if (ph->core->interp_fd >= 0) 57 close(ph->core->interp_fd); 58 59 // close class share archive file 60 if (ph->core->classes_jsa_fd >= 0) 61 close(ph->core->classes_jsa_fd); 62 63 // close all library file descriptors 64 lib = ph->libs; 65 while (lib) { 66 int fd = lib->fd; 67 if (fd >= 0 && fd != ph->core->exec_fd) { 68 close(fd); 69 } 70 lib = lib->next; 71 } 72 } 73 74 // clean all map_info stuff 75 static void destroy_map_info(struct ps_prochandle* ph) { 76 map_info* map = ph->core->maps; 77 while (map) { 78 map_info* next = map->next; 79 free(map); 80 map = next; 81 } 82 83 if (ph->core->map_array) { 84 free(ph->core->map_array); 85 } 86 87 // Part of the class sharing workaround 88 map = ph->core->class_share_maps; 89 while (map) { 90 map_info* next = map->next; 91 free(map); 92 map = next; 93 } 94 } 95 96 // ps_prochandle operations 97 static void core_release(struct ps_prochandle* ph) { 98 if (ph->core) { 99 close_files(ph); 100 destroy_map_info(ph); 101 free(ph->core); 102 } 103 } 104 105 static map_info* allocate_init_map(int fd, off_t offset, uintptr_t vaddr, size_t memsz) { 106 map_info* map; 107 if ( (map = (map_info*) calloc(1, sizeof(map_info))) == NULL) { 108 print_debug("can't allocate memory for map_info\n"); 109 return NULL; 110 } 111 112 // initialize map 113 map->fd = fd; 114 map->offset = offset; 115 map->vaddr = vaddr; 116 map->memsz = memsz; 117 return map; 118 } 119 120 // add map info with given fd, offset, vaddr and memsz 121 static map_info* add_map_info(struct ps_prochandle* ph, int fd, off_t offset, 122 uintptr_t vaddr, size_t memsz) { 123 map_info* map; 124 if ((map = allocate_init_map(fd, offset, vaddr, memsz)) == NULL) { 125 return NULL; 126 } 127 128 // add this to map list 129 map->next = ph->core->maps; 130 ph->core->maps = map; 131 ph->core->num_maps++; 132 133 return map; 134 } 135 136 // Part of the class sharing workaround 137 static map_info* add_class_share_map_info(struct ps_prochandle* ph, off_t offset, 138 uintptr_t vaddr, size_t memsz) { 139 map_info* map; 140 if ((map = allocate_init_map(ph->core->classes_jsa_fd, 141 offset, vaddr, memsz)) == NULL) { 142 return NULL; 143 } 144 145 map->next = ph->core->class_share_maps; 146 ph->core->class_share_maps = map; 147 return map; 148 } 149 150 // Return the map_info for the given virtual address. We keep a sorted 151 // array of pointers in ph->map_array, so we can binary search. 152 static map_info* core_lookup(struct ps_prochandle *ph, uintptr_t addr) 153 { 154 int mid, lo = 0, hi = ph->core->num_maps - 1; 155 map_info *mp; 156 157 while (hi - lo > 1) { 158 mid = (lo + hi) / 2; 159 if (addr >= ph->core->map_array[mid]->vaddr) { 160 lo = mid; 161 } else { 162 hi = mid; 163 } 164 } 165 166 if (addr < ph->core->map_array[hi]->vaddr) { 167 mp = ph->core->map_array[lo]; 168 } else { 169 mp = ph->core->map_array[hi]; 170 } 171 172 if (addr >= mp->vaddr && addr < mp->vaddr + mp->memsz) { 173 return (mp); 174 } 175 176 177 // Part of the class sharing workaround 178 // Unfortunately, we have no way of detecting -Xshare state. 179 // Check out the share maps atlast, if we don't find anywhere. 180 // This is done this way so to avoid reading share pages 181 // ahead of other normal maps. For eg. with -Xshare:off we don't 182 // want to prefer class sharing data to data from core. 183 mp = ph->core->class_share_maps; 184 if (mp) { 185 print_debug("can't locate map_info at 0x%lx, trying class share maps\n", addr); 186 } 187 while (mp) { 188 if (addr >= mp->vaddr && addr < mp->vaddr + mp->memsz) { 189 print_debug("located map_info at 0x%lx from class share maps\n", addr); 190 return (mp); 191 } 192 mp = mp->next; 193 } 194 195 print_debug("can't locate map_info at 0x%lx\n", addr); 196 return (NULL); 197 } 198 199 //--------------------------------------------------------------- 200 // Part of the class sharing workaround: 201 // 202 // With class sharing, pages are mapped from classes[_g].jsa file. 203 // The read-only class sharing pages are mapped as MAP_SHARED, 204 // PROT_READ pages. These pages are not dumped into core dump. 205 // With this workaround, these pages are read from classes[_g].jsa. 206 207 // FIXME: !HACK ALERT! 208 // The format of sharing achive file header is needed to read shared heap 209 // file mappings. For now, I am hard coding portion of FileMapHeader here. 210 // Refer to filemap.hpp. 211 212 // FileMapHeader describes the shared space data in the file to be 213 // mapped. This structure gets written to a file. It is not a class, 214 // so that the compilers don't add any compiler-private data to it. 215 216 #define NUM_SHARED_MAPS 4 217 218 // Refer to FileMapInfo::_current_version in filemap.hpp 219 #define CURRENT_ARCHIVE_VERSION 1 220 221 struct FileMapHeader { 222 int _magic; // identify file type. 223 int _version; // (from enum, above.) 224 size_t _alignment; // how shared archive should be aligned 225 226 struct space_info { 227 int _file_offset; // sizeof(this) rounded to vm page size 228 char* _base; // copy-on-write base address 229 size_t _capacity; // for validity checking 230 size_t _used; // for setting space top on read 231 232 // 4991491 NOTICE These are C++ bool's in filemap.hpp and must match up with 233 // the C type matching the C++ bool type on any given platform. For 234 // Hotspot on BSD we assume the corresponding C type is char but 235 // licensees on BSD versions may need to adjust the type of these fields. 236 char _read_only; // read only space? 237 char _allow_exec; // executable code in space? 238 239 } _space[NUM_SHARED_MAPS]; 240 241 // Ignore the rest of the FileMapHeader. We don't need those fields here. 242 }; 243 244 static bool read_jboolean(struct ps_prochandle* ph, uintptr_t addr, jboolean* pvalue) { 245 jboolean i; 246 if (ps_pread(ph, (psaddr_t) addr, &i, sizeof(i)) == PS_OK) { 247 *pvalue = i; 248 return true; 249 } else { 250 return false; 251 } 252 } 253 254 static bool read_pointer(struct ps_prochandle* ph, uintptr_t addr, uintptr_t* pvalue) { 255 uintptr_t uip; 256 if (ps_pread(ph, (psaddr_t) addr, (char *)&uip, sizeof(uip)) == PS_OK) { 257 *pvalue = uip; 258 return true; 259 } else { 260 return false; 261 } 262 } 263 264 // used to read strings from debuggee 265 static bool read_string(struct ps_prochandle* ph, uintptr_t addr, char* buf, size_t size) { 266 size_t i = 0; 267 char c = ' '; 268 269 while (c != '\0') { 270 if (ps_pread(ph, (psaddr_t) addr, &c, sizeof(char)) != PS_OK) { 271 return false; 272 } 273 if (i < size - 1) { 274 buf[i] = c; 275 } else { 276 // smaller buffer 277 return false; 278 } 279 i++; addr++; 280 } 281 buf[i] = '\0'; 282 return true; 283 } 284 285 #ifdef __APPLE__ 286 #define USE_SHARED_SPACES_SYM "_UseSharedSpaces" 287 // mangled name of Arguments::SharedArchivePath 288 #define SHARED_ARCHIVE_PATH_SYM "_ZN9Arguments17SharedArchivePathE" 289 #else 290 #define USE_SHARED_SPACES_SYM "UseSharedSpaces" 291 // mangled name of Arguments::SharedArchivePath 292 #define SHARED_ARCHIVE_PATH_SYM "__ZN9Arguments17SharedArchivePathE" 293 #endif // __APPLE_ 294 295 static bool init_classsharing_workaround(struct ps_prochandle* ph) { 296 int m; 297 size_t n; 298 lib_info* lib = ph->libs; 299 while (lib != NULL) { 300 // we are iterating over shared objects from the core dump. look for 301 // libjvm[_g].so. 302 const char *jvm_name = 0; 303 #ifdef __APPLE__ 304 if ((jvm_name = strstr(lib->name, "/libjvm.dylib")) != 0 || 305 (jvm_name = strstr(lib->name, "/libjvm_g.dylib")) != 0) 306 #else 307 if ((jvm_name = strstr(lib->name, "/libjvm.so")) != 0 || 308 (jvm_name = strstr(lib->name, "/libjvm_g.so")) != 0) 309 #endif // __APPLE__ 310 { 311 char classes_jsa[PATH_MAX]; 312 struct FileMapHeader header; 313 int fd = -1; 314 uintptr_t base = 0, useSharedSpacesAddr = 0; 315 uintptr_t sharedArchivePathAddrAddr = 0, sharedArchivePathAddr = 0; 316 jboolean useSharedSpaces = 0; 317 318 memset(classes_jsa, 0, sizeof(classes_jsa)); 319 jvm_name = lib->name; 320 useSharedSpacesAddr = lookup_symbol(ph, jvm_name, USE_SHARED_SPACES_SYM); 321 if (useSharedSpacesAddr == 0) { 322 print_debug("can't lookup 'UseSharedSpaces' flag\n"); 323 return false; 324 } 325 326 // Hotspot vm types are not exported to build this library. So 327 // using equivalent type jboolean to read the value of 328 // UseSharedSpaces which is same as hotspot type "bool". 329 if (read_jboolean(ph, useSharedSpacesAddr, &useSharedSpaces) != true) { 330 print_debug("can't read the value of 'UseSharedSpaces' flag\n"); 331 return false; 332 } 333 334 if ((int)useSharedSpaces == 0) { 335 print_debug("UseSharedSpaces is false, assuming -Xshare:off!\n"); 336 return true; 337 } 338 339 sharedArchivePathAddrAddr = lookup_symbol(ph, jvm_name, SHARED_ARCHIVE_PATH_SYM); 340 if (sharedArchivePathAddrAddr == 0) { 341 print_debug("can't lookup shared archive path symbol\n"); 342 return false; 343 } 344 345 if (read_pointer(ph, sharedArchivePathAddrAddr, &sharedArchivePathAddr) != true) { 346 print_debug("can't read shared archive path pointer\n"); 347 return false; 348 } 349 350 if (read_string(ph, sharedArchivePathAddr, classes_jsa, sizeof(classes_jsa)) != true) { 351 print_debug("can't read shared archive path value\n"); 352 return false; 353 } 354 355 print_debug("looking for %s\n", classes_jsa); 356 // open the class sharing archive file 357 fd = pathmap_open(classes_jsa); 358 if (fd < 0) { 359 print_debug("can't open %s!\n", classes_jsa); 360 ph->core->classes_jsa_fd = -1; 361 return false; 362 } else { 363 print_debug("opened %s\n", classes_jsa); 364 } 365 366 // read FileMapHeader from the file 367 memset(&header, 0, sizeof(struct FileMapHeader)); 368 if ((n = read(fd, &header, sizeof(struct FileMapHeader))) 369 != sizeof(struct FileMapHeader)) { 370 print_debug("can't read shared archive file map header from %s\n", classes_jsa); 371 close(fd); 372 return false; 373 } 374 375 // check file magic 376 if (header._magic != 0xf00baba2) { 377 print_debug("%s has bad shared archive file magic number 0x%x, expecing 0xf00baba2\n", 378 classes_jsa, header._magic); 379 close(fd); 380 return false; 381 } 382 383 // check version 384 if (header._version != CURRENT_ARCHIVE_VERSION) { 385 print_debug("%s has wrong shared archive file version %d, expecting %d\n", 386 classes_jsa, header._version, CURRENT_ARCHIVE_VERSION); 387 close(fd); 388 return false; 389 } 390 391 ph->core->classes_jsa_fd = fd; 392 // add read-only maps from classes[_g].jsa to the list of maps 393 for (m = 0; m < NUM_SHARED_MAPS; m++) { 394 if (header._space[m]._read_only) { 395 base = (uintptr_t) header._space[m]._base; 396 // no need to worry about the fractional pages at-the-end. 397 // possible fractional pages are handled by core_read_data. 398 add_class_share_map_info(ph, (off_t) header._space[m]._file_offset, 399 base, (size_t) header._space[m]._used); 400 print_debug("added a share archive map at 0x%lx\n", base); 401 } 402 } 403 return true; 404 } 405 lib = lib->next; 406 } 407 return true; 408 } 409 410 //--------------------------------------------------------------------------- 411 // functions to handle map_info 412 413 // Order mappings based on virtual address. We use this function as the 414 // callback for sorting the array of map_info pointers. 415 static int core_cmp_mapping(const void *lhsp, const void *rhsp) 416 { 417 const map_info *lhs = *((const map_info **)lhsp); 418 const map_info *rhs = *((const map_info **)rhsp); 419 420 if (lhs->vaddr == rhs->vaddr) { 421 return (0); 422 } 423 424 return (lhs->vaddr < rhs->vaddr ? -1 : 1); 425 } 426 427 // we sort map_info by starting virtual address so that we can do 428 // binary search to read from an address. 429 static bool sort_map_array(struct ps_prochandle* ph) { 430 size_t num_maps = ph->core->num_maps; 431 map_info* map = ph->core->maps; 432 int i = 0; 433 434 // allocate map_array 435 map_info** array; 436 if ( (array = (map_info**) malloc(sizeof(map_info*) * num_maps)) == NULL) { 437 print_debug("can't allocate memory for map array\n"); 438 return false; 439 } 440 441 // add maps to array 442 while (map) { 443 array[i] = map; 444 i++; 445 map = map->next; 446 } 447 448 // sort is called twice. If this is second time, clear map array 449 if (ph->core->map_array) { 450 free(ph->core->map_array); 451 } 452 ph->core->map_array = array; 453 // sort the map_info array by base virtual address. 454 qsort(ph->core->map_array, ph->core->num_maps, sizeof (map_info*), 455 core_cmp_mapping); 456 457 // print map 458 if (is_debug()) { 459 int j = 0; 460 print_debug("---- sorted virtual address map ----\n"); 461 for (j = 0; j < ph->core->num_maps; j++) { 462 print_debug("base = 0x%lx\tsize = %d\n", ph->core->map_array[j]->vaddr, 463 ph->core->map_array[j]->memsz); 464 } 465 } 466 467 return true; 468 } 469 470 #ifndef MIN 471 #define MIN(x, y) (((x) < (y))? (x): (y)) 472 #endif 473 474 static bool core_read_data(struct ps_prochandle* ph, uintptr_t addr, char *buf, size_t size) { 475 ssize_t resid = size; 476 int page_size=sysconf(_SC_PAGE_SIZE); 477 while (resid != 0) { 478 map_info *mp = core_lookup(ph, addr); 479 uintptr_t mapoff; 480 ssize_t len, rem; 481 off_t off; 482 int fd; 483 484 if (mp == NULL) { 485 break; /* No mapping for this address */ 486 } 487 488 fd = mp->fd; 489 mapoff = addr - mp->vaddr; 490 len = MIN(resid, mp->memsz - mapoff); 491 off = mp->offset + mapoff; 492 493 if ((len = pread(fd, buf, len, off)) <= 0) { 494 break; 495 } 496 497 resid -= len; 498 addr += len; 499 buf = (char *)buf + len; 500 501 // mappings always start at page boundary. But, may end in fractional 502 // page. fill zeros for possible fractional page at the end of a mapping. 503 rem = mp->memsz % page_size; 504 if (rem > 0) { 505 rem = page_size - rem; 506 len = MIN(resid, rem); 507 resid -= len; 508 addr += len; 509 // we are not assuming 'buf' to be zero initialized. 510 memset(buf, 0, len); 511 buf += len; 512 } 513 } 514 515 if (resid) { 516 print_debug("core read failed for %d byte(s) @ 0x%lx (%d more bytes)\n", 517 size, addr, resid); 518 return false; 519 } else { 520 return true; 521 } 522 } 523 524 // null implementation for write 525 static bool core_write_data(struct ps_prochandle* ph, 526 uintptr_t addr, const char *buf , size_t size) { 527 return false; 528 } 529 530 static bool core_get_lwp_regs(struct ps_prochandle* ph, lwpid_t lwp_id, 531 struct reg* regs) { 532 // for core we have cached the lwp regs after segment parsed 533 sa_thread_info* thr = ph->threads; 534 while (thr) { 535 if (thr->lwp_id == lwp_id) { 536 memcpy(regs, &thr->regs, sizeof(struct reg)); 537 return true; 538 } 539 thr = thr->next; 540 } 541 return false; 542 } 543 544 static bool core_get_lwp_info(struct ps_prochandle *ph, lwpid_t id, void *info) { 545 print_debug("core_get_lwp_info not implemented\n"); 546 return false; 547 } 548 549 static ps_prochandle_ops core_ops = { 550 .release= core_release, 551 .p_pread= core_read_data, 552 .p_pwrite= core_write_data, 553 .get_lwp_regs= core_get_lwp_regs, 554 .get_lwp_info= core_get_lwp_info 555 }; 556 557 // from this point, mainly two blocks divided by def __APPLE__ 558 // one for Macosx, the other for regular Bsd 559 560 #ifdef __APPLE__ 561 562 void print_thread(sa_thread_info *threadinfo) { 563 print_debug("thread added: %d\n", threadinfo->lwp_id); 564 print_debug("registers:\n"); 565 print_debug(" r_r15: 0x%" PRIx64 "\n", threadinfo->regs.r_r15); 566 print_debug(" r_r14: 0x%" PRIx64 "\n", threadinfo->regs.r_r14); 567 print_debug(" r_r13: 0x%" PRIx64 "\n", threadinfo->regs.r_r13); 568 print_debug(" r_r12: 0x%" PRIx64 "\n", threadinfo->regs.r_r12); 569 print_debug(" r_r11: 0x%" PRIx64 "\n", threadinfo->regs.r_r11); 570 print_debug(" r_r10: 0x%" PRIx64 "\n", threadinfo->regs.r_r10); 571 print_debug(" r_r9: 0x%" PRIx64 "\n", threadinfo->regs.r_r9); 572 print_debug(" r_r8: 0x%" PRIx64 "\n", threadinfo->regs.r_r8); 573 print_debug(" r_rdi: 0x%" PRIx64 "\n", threadinfo->regs.r_rdi); 574 print_debug(" r_rsi: 0x%" PRIx64 "\n", threadinfo->regs.r_rsi); 575 print_debug(" r_rbp: 0x%" PRIx64 "\n", threadinfo->regs.r_rbp); 576 print_debug(" r_rbx: 0x%" PRIx64 "\n", threadinfo->regs.r_rbx); 577 print_debug(" r_rdx: 0x%" PRIx64 "\n", threadinfo->regs.r_rdx); 578 print_debug(" r_rcx: 0x%" PRIx64 "\n", threadinfo->regs.r_rcx); 579 print_debug(" r_rax: 0x%" PRIx64 "\n", threadinfo->regs.r_rax); 580 print_debug(" r_fs: 0x%" PRIx32 "\n", threadinfo->regs.r_fs); 581 print_debug(" r_gs: 0x%" PRIx32 "\n", threadinfo->regs.r_gs); 582 print_debug(" r_rip 0x%" PRIx64 "\n", threadinfo->regs.r_rip); 583 print_debug(" r_cs: 0x%" PRIx64 "\n", threadinfo->regs.r_cs); 584 print_debug(" r_rsp: 0x%" PRIx64 "\n", threadinfo->regs.r_rsp); 585 print_debug(" r_rflags: 0x%" PRIx64 "\n", threadinfo->regs.r_rflags); 586 } 587 588 // read all segments64 commands from core file 589 // read all thread commands from core file 590 static bool read_core_segments(struct ps_prochandle* ph) { 591 int i = 0; 592 int num_threads = 0; 593 int fd = ph->core->core_fd; 594 off_t offset = 0; 595 mach_header_64 fhead; 596 load_command lcmd; 597 segment_command_64 segcmd; 598 // thread_command thrcmd; 599 600 lseek(fd, offset, SEEK_SET); 601 if(read(fd, (void *)&fhead, sizeof(mach_header_64)) != sizeof(mach_header_64)) { 602 goto err; 603 } 604 print_debug("total commands: %d\n", fhead.ncmds); 605 offset += sizeof(mach_header_64); 606 for (i = 0; i < fhead.ncmds; i++) { 607 lseek(fd, offset, SEEK_SET); 608 if (read(fd, (void *)&lcmd, sizeof(load_command)) != sizeof(load_command)) { 609 goto err; 610 } 611 offset += lcmd.cmdsize; // next command position 612 if (lcmd.cmd == LC_SEGMENT_64) { 613 lseek(fd, -sizeof(load_command), SEEK_CUR); 614 if (read(fd, (void *)&segcmd, sizeof(segment_command_64)) != sizeof(segment_command_64)) { 615 print_debug("failed to read LC_SEGMENT_64 i = %d!\n", i); 616 goto err; 617 } 618 if (add_map_info(ph, fd, segcmd.fileoff, segcmd.vmaddr, segcmd.vmsize) == NULL) { 619 print_debug("Failed to add map_info at i = %d\n", i); 620 goto err; 621 } 622 print_debug("segment added: %" PRIu64 " 0x%" PRIx64 " %d\n", 623 segcmd.fileoff, segcmd.vmaddr, segcmd.vmsize); 624 } else if (lcmd.cmd == LC_THREAD || lcmd.cmd == LC_UNIXTHREAD) { 625 typedef struct thread_fc { 626 uint32_t flavor; 627 uint32_t count; 628 } thread_fc; 629 thread_fc fc; 630 uint32_t size = sizeof(load_command); 631 while (size < lcmd.cmdsize) { 632 if (read(fd, (void *)&fc, sizeof(thread_fc)) != sizeof(thread_fc)) { 633 printf("Reading flavor, count failed.\n"); 634 goto err; 635 } 636 size += sizeof(thread_fc); 637 if (fc.flavor == x86_THREAD_STATE) { 638 x86_thread_state_t thrstate; 639 if (read(fd, (void *)&thrstate, sizeof(x86_thread_state_t)) != sizeof(x86_thread_state_t)) { 640 printf("Reading flavor, count failed.\n"); 641 goto err; 642 } 643 size += sizeof(x86_thread_state_t); 644 // create thread info list, update lwp_id later 645 sa_thread_info* newthr = add_thread_info(ph, (pthread_t) -1, (lwpid_t) num_threads++); 646 if (newthr == NULL) { 647 printf("create thread_info failed\n"); 648 goto err; 649 } 650 651 // note __DARWIN_UNIX03 depengs on other definitions 652 #if __DARWIN_UNIX03 653 #define get_register_v(regst, regname) \ 654 regst.uts.ts64.__##regname 655 #else 656 #define get_register_v(regst, regname) \ 657 regst.uts.ts64.##regname 658 #endif // __DARWIN_UNIX03 659 newthr->regs.r_rax = get_register_v(thrstate, rax); 660 newthr->regs.r_rbx = get_register_v(thrstate, rbx); 661 newthr->regs.r_rcx = get_register_v(thrstate, rcx); 662 newthr->regs.r_rdx = get_register_v(thrstate, rdx); 663 newthr->regs.r_rdi = get_register_v(thrstate, rdi); 664 newthr->regs.r_rsi = get_register_v(thrstate, rsi); 665 newthr->regs.r_rbp = get_register_v(thrstate, rbp); 666 newthr->regs.r_rsp = get_register_v(thrstate, rsp); 667 newthr->regs.r_r8 = get_register_v(thrstate, r8); 668 newthr->regs.r_r9 = get_register_v(thrstate, r9); 669 newthr->regs.r_r10 = get_register_v(thrstate, r10); 670 newthr->regs.r_r11 = get_register_v(thrstate, r11); 671 newthr->regs.r_r12 = get_register_v(thrstate, r12); 672 newthr->regs.r_r13 = get_register_v(thrstate, r13); 673 newthr->regs.r_r14 = get_register_v(thrstate, r14); 674 newthr->regs.r_r15 = get_register_v(thrstate, r15); 675 newthr->regs.r_rip = get_register_v(thrstate, rip); 676 newthr->regs.r_rflags = get_register_v(thrstate, rflags); 677 newthr->regs.r_cs = get_register_v(thrstate, cs); 678 newthr->regs.r_fs = get_register_v(thrstate, fs); 679 newthr->regs.r_gs = get_register_v(thrstate, gs); 680 print_thread(newthr); 681 } else if (fc.flavor == x86_FLOAT_STATE) { 682 x86_float_state_t flstate; 683 if (read(fd, (void *)&flstate, sizeof(x86_float_state_t)) != sizeof(x86_float_state_t)) { 684 print_debug("Reading flavor, count failed.\n"); 685 goto err; 686 } 687 size += sizeof(x86_float_state_t); 688 } else if (fc.flavor == x86_EXCEPTION_STATE) { 689 x86_exception_state_t excpstate; 690 if (read(fd, (void *)&excpstate, sizeof(x86_exception_state_t)) != sizeof(x86_exception_state_t)) { 691 printf("Reading flavor, count failed.\n"); 692 goto err; 693 } 694 size += sizeof(x86_exception_state_t); 695 } 696 } 697 } 698 } 699 return true; 700 err: 701 return false; 702 } 703 704 /**local function **/ 705 bool exists(const char *fname) 706 { 707 int fd; 708 if ((fd = open(fname, O_RDONLY)) > 0) { 709 close(fd); 710 return true; 711 } 712 return false; 713 } 714 715 // we check: 1. lib 716 // 2. lib/server 717 // 3. jre/lib 718 // 4. jre/lib/server 719 // from: 1. exe path 720 // 2. JAVA_HOME 721 // 3. DYLD_LIBRARY_PATH 722 static bool get_real_path(struct ps_prochandle* ph, char *rpath) { 723 /** check if they exist in JAVA ***/ 724 char* execname = ph->core->exec_path; 725 char filepath[4096]; 726 char* filename = strrchr(rpath, '/'); // like /libjvm.dylib 727 if (filename == NULL) { 728 return false; 729 } 730 731 char* posbin = strstr(execname, "/bin/java"); 732 if (posbin != NULL) { 733 memcpy(filepath, execname, posbin - execname); // not include trailing '/' 734 filepath[posbin - execname] = '\0'; 735 } else { 736 char* java_home = getenv("JAVA_HOME"); 737 if (java_home != NULL) { 738 strcpy(filepath, java_home); 739 } else { 740 char* dyldpath = getenv("DYLD_LIBRARY_PATH"); 741 char* dypath = strtok(dyldpath, ":"); 742 while (dypath != NULL) { 743 strcpy(filepath, dypath); 744 strcat(filepath, filename); 745 if (exists(filepath)) { 746 strcpy(rpath, filepath); 747 return true; 748 } 749 dypath = strtok(dyldpath, ":"); 750 } 751 // not found 752 return false; 753 } 754 } 755 // for exec and java_home, jdkpath now is filepath 756 size_t filepath_base_size = strlen(filepath); 757 758 // first try /lib/ and /lib/server 759 strcat(filepath, "/lib"); 760 strcat(filepath, filename); 761 if (exists(filepath)) { 762 strcpy(rpath, filepath); 763 return true; 764 } 765 char* pos = strstr(filepath, filename); // like /libjvm.dylib 766 *pos = '\0'; 767 strcat(filepath, "/server"); 768 strcat(filepath, filename); 769 if (exists(filepath)) { 770 strcpy(rpath, filepath); 771 return true; 772 } 773 774 775 // then try /jre/lib/ and /jre/lib/server 776 filepath[filepath_base_size] = '\0'; 777 strcat(filepath, "/jre/lib"); 778 strcat(filepath, filename); 779 if (exists(filepath)) { 780 strcpy(rpath, filepath); 781 return true; 782 } 783 pos = strstr(filepath, filename); 784 *pos = '\0'; 785 strcat(filepath, "/server"); 786 strcat(filepath, filename); 787 if (exists(filepath)) { 788 strcpy(rpath, filepath); 789 return true; 790 } 791 792 return false; 793 } 794 795 static bool read_shared_lib_info(struct ps_prochandle* ph) { 796 static int pagesize = 0; 797 int fd = ph->core->core_fd; 798 int i = 0, j; 799 uint32_t v; 800 mach_header_64 header; // used to check if a file header in segment 801 load_command lcmd; 802 dylib_command dylibcmd; 803 804 char name[BUF_SIZE]; // use to store name 805 806 if (pagesize == 0) { 807 pagesize = getpagesize(); 808 print_debug("page size is %d\n", pagesize); 809 } 810 for (j = 0; j < ph->core->num_maps; j++) { 811 map_info *iter = ph->core->map_array[j]; // head 812 off_t fpos = iter->offset; 813 if (iter->fd != fd) { 814 // only search core file! 815 continue; 816 } 817 print_debug("map_info %d: vmaddr = 0x%016" PRIx64 " fileoff = %" PRIu64 " vmsize = %" PRIu64 "\n", 818 j, iter->vaddr, iter->offset, iter->memsz); 819 lseek(fd, fpos, SEEK_SET); 820 // we assume .dylib loaded at segment address --- which is true for JVM libraries 821 // multiple files may be loaded in one segment. 822 // if first word is not a magic word, means this segment does not contain lib file. 823 if (read(fd, (void *)&v, sizeof(uint32_t)) == sizeof(uint32_t)) { 824 if (v != MH_MAGIC_64) { 825 continue; 826 } 827 } else { 828 // may be encountered last map, which is not readable 829 continue; 830 } 831 while (ltell(fd) - iter->offset < iter->memsz) { 832 lseek(fd, fpos, SEEK_SET); 833 if (read(fd, (void *)&v, sizeof(uint32_t)) != sizeof(uint32_t)) { 834 break; 835 } 836 if (v != MH_MAGIC_64) { 837 fpos = (ltell(fd) + pagesize -1)/pagesize * pagesize; 838 continue; 839 } 840 lseek(fd, -sizeof(uint32_t), SEEK_CUR); 841 // this is the file begining to core file. 842 if (read(fd, (void *)&header, sizeof(mach_header_64)) != sizeof(mach_header_64)) { 843 goto err; 844 } 845 fpos = ltell(fd); 846 847 // found a mach-o file in this segment 848 for (i = 0; i < header.ncmds; i++) { 849 // read commands in this "file" 850 // LC_ID_DYLIB is the file itself for a .dylib 851 lseek(fd, fpos, SEEK_SET); 852 if (read(fd, (void *)&lcmd, sizeof(load_command)) != sizeof(load_command)) { 853 return false; // error 854 } 855 fpos += lcmd.cmdsize; // next command position 856 // make sure still within seg size. 857 if (fpos - lcmd.cmdsize - iter->offset > iter->memsz) { 858 print_debug("Warning: out of segement limit: %ld \n", fpos - lcmd.cmdsize - iter->offset); 859 break; // no need to iterate all commands 860 } 861 if (lcmd.cmd == LC_ID_DYLIB) { 862 lseek(fd, -sizeof(load_command), SEEK_CUR); 863 if (read(fd, (void *)&dylibcmd, sizeof(dylib_command)) != sizeof(dylib_command)) { 864 return false; 865 } 866 /**** name stored at dylib_command.dylib.name.offset, is a C string */ 867 lseek(fd, dylibcmd.dylib.name.offset - sizeof(dylib_command), SEEK_CUR); 868 int j = 0; 869 while (j < BUF_SIZE) { 870 read(fd, (void *)(name + j), sizeof(char)); 871 if (name[j] == '\0') break; 872 j++; 873 } 874 print_debug("%s\n", name); 875 // changed name from @rpath/xxxx.dylib to real path 876 if (strrchr(name, '@')) { 877 get_real_path(ph, name); 878 print_debug("get_real_path returned: %s\n", name); 879 } 880 add_lib_info(ph, name, iter->vaddr); 881 break; 882 } 883 } 884 // done with the file, advanced to next page to search more files 885 fpos = (ltell(fd) + pagesize - 1) / pagesize * pagesize; 886 } 887 } 888 return true; 889 err: 890 return false; 891 } 892 893 bool read_macho64_header(int fd, mach_header_64* core_header) { 894 bool is_macho = false; 895 if (fd < 0) return false; 896 off_t pos = ltell(fd); 897 lseek(fd, 0, SEEK_SET); 898 if (read(fd, (void *)core_header, sizeof(mach_header_64)) != sizeof(mach_header_64)) { 899 is_macho = false; 900 } else { 901 is_macho = (core_header->magic == MH_MAGIC_64 || core_header->magic == MH_CIGAM_64); 902 } 903 lseek(fd, pos, SEEK_SET); 904 return is_macho; 905 } 906 907 // the one and only one exposed stuff from this file 908 struct ps_prochandle* Pgrab_core(const char* exec_file, const char* core_file) { 909 mach_header_64 core_header; 910 mach_header_64 exec_header; 911 912 struct ps_prochandle* ph = (struct ps_prochandle*) calloc(1, sizeof(struct ps_prochandle)); 913 if (ph == NULL) { 914 print_debug("cant allocate ps_prochandle\n"); 915 return NULL; 916 } 917 918 if ((ph->core = (struct core_data*) calloc(1, sizeof(struct core_data))) == NULL) { 919 free(ph); 920 print_debug("can't allocate ps_prochandle\n"); 921 return NULL; 922 } 923 924 // initialize ph 925 ph->ops = &core_ops; 926 ph->core->core_fd = -1; 927 ph->core->exec_fd = -1; 928 ph->core->interp_fd = -1; 929 930 print_debug("exec: %s core: %s", exec_file, core_file); 931 932 strncpy(ph->core->exec_path, exec_file, sizeof(ph->core->exec_path)); 933 934 // open the core file 935 if ((ph->core->core_fd = open(core_file, O_RDONLY)) < 0) { 936 print_error("can't open core file\n"); 937 goto err; 938 } 939 940 // read core file header 941 if (read_macho64_header(ph->core->core_fd, &core_header) != true || core_header.filetype != MH_CORE) { 942 print_debug("core file is not a valid Mach-O file\n"); 943 goto err; 944 } 945 946 if ((ph->core->exec_fd = open(exec_file, O_RDONLY)) < 0) { 947 print_error("can't open executable file\n"); 948 goto err; 949 } 950 951 if (read_macho64_header(ph->core->exec_fd, &exec_header) != true || 952 exec_header.filetype != MH_EXECUTE) { 953 print_error("executable file is not a valid Mach-O file\n"); 954 goto err; 955 } 956 957 // process core file segments 958 if (read_core_segments(ph) != true) { 959 print_error("failed to read core segments\n"); 960 goto err; 961 } 962 963 // allocate and sort maps into map_array, we need to do this 964 // here because read_shared_lib_info needs to read from debuggee 965 // address space 966 if (sort_map_array(ph) != true) { 967 print_error("failed to sort segment map array\n"); 968 goto err; 969 } 970 971 if (read_shared_lib_info(ph) != true) { 972 print_error("failed to read libraries\n"); 973 goto err; 974 } 975 976 // sort again because we have added more mappings from shared objects 977 if (sort_map_array(ph) != true) { 978 print_error("failed to sort segment map array\n"); 979 goto err; 980 } 981 982 if (init_classsharing_workaround(ph) != true) { 983 print_error("failed to workaround classshareing\n"); 984 goto err; 985 } 986 987 print_debug("Leave Pgrab_core\n"); 988 return ph; 989 990 err: 991 Prelease(ph); 992 return NULL; 993 } 994 995 #else // __APPLE__ (none macosx) 996 997 // read regs and create thread from core file 998 static bool core_handle_prstatus(struct ps_prochandle* ph, const char* buf, size_t nbytes) { 999 // we have to read prstatus_t from buf 1000 // assert(nbytes == sizeof(prstaus_t), "size mismatch on prstatus_t"); 1001 prstatus_t* prstat = (prstatus_t*) buf; 1002 sa_thread_info* newthr; 1003 print_debug("got integer regset for lwp %d\n", prstat->pr_pid); 1004 // we set pthread_t to -1 for core dump 1005 if((newthr = add_thread_info(ph, (pthread_t) -1, prstat->pr_pid)) == NULL) 1006 return false; 1007 1008 // copy regs 1009 memcpy(&newthr->regs, &prstat->pr_reg, sizeof(struct reg)); 1010 1011 if (is_debug()) { 1012 print_debug("integer regset\n"); 1013 #ifdef i386 1014 // print the regset 1015 print_debug("\teax = 0x%x\n", newthr->regs.r_eax); 1016 print_debug("\tebx = 0x%x\n", newthr->regs.r_ebx); 1017 print_debug("\tecx = 0x%x\n", newthr->regs.r_ecx); 1018 print_debug("\tedx = 0x%x\n", newthr->regs.r_edx); 1019 print_debug("\tesp = 0x%x\n", newthr->regs.r_esp); 1020 print_debug("\tebp = 0x%x\n", newthr->regs.r_ebp); 1021 print_debug("\tesi = 0x%x\n", newthr->regs.r_esi); 1022 print_debug("\tedi = 0x%x\n", newthr->regs.r_edi); 1023 print_debug("\teip = 0x%x\n", newthr->regs.r_eip); 1024 #endif 1025 1026 #if defined(amd64) || defined(x86_64) 1027 // print the regset 1028 print_debug("\tr15 = 0x%lx\n", newthr->regs.r_r15); 1029 print_debug("\tr14 = 0x%lx\n", newthr->regs.r_r14); 1030 print_debug("\tr13 = 0x%lx\n", newthr->regs.r_r13); 1031 print_debug("\tr12 = 0x%lx\n", newthr->regs.r_r12); 1032 print_debug("\trbp = 0x%lx\n", newthr->regs.r_rbp); 1033 print_debug("\trbx = 0x%lx\n", newthr->regs.r_rbx); 1034 print_debug("\tr11 = 0x%lx\n", newthr->regs.r_r11); 1035 print_debug("\tr10 = 0x%lx\n", newthr->regs.r_r10); 1036 print_debug("\tr9 = 0x%lx\n", newthr->regs.r_r9); 1037 print_debug("\tr8 = 0x%lx\n", newthr->regs.r_r8); 1038 print_debug("\trax = 0x%lx\n", newthr->regs.r_rax); 1039 print_debug("\trcx = 0x%lx\n", newthr->regs.r_rcx); 1040 print_debug("\trdx = 0x%lx\n", newthr->regs.r_rdx); 1041 print_debug("\trsi = 0x%lx\n", newthr->regs.r_rsi); 1042 print_debug("\trdi = 0x%lx\n", newthr->regs.r_rdi); 1043 //print_debug("\torig_rax = 0x%lx\n", newthr->regs.orig_rax); 1044 print_debug("\trip = 0x%lx\n", newthr->regs.r_rip); 1045 print_debug("\tcs = 0x%lx\n", newthr->regs.r_cs); 1046 //print_debug("\teflags = 0x%lx\n", newthr->regs.eflags); 1047 print_debug("\trsp = 0x%lx\n", newthr->regs.r_rsp); 1048 print_debug("\tss = 0x%lx\n", newthr->regs.r_ss); 1049 //print_debug("\tfs_base = 0x%lx\n", newthr->regs.fs_base); 1050 //print_debug("\tgs_base = 0x%lx\n", newthr->regs.gs_base); 1051 //print_debug("\tds = 0x%lx\n", newthr->regs.ds); 1052 //print_debug("\tes = 0x%lx\n", newthr->regs.es); 1053 //print_debug("\tfs = 0x%lx\n", newthr->regs.fs); 1054 //print_debug("\tgs = 0x%lx\n", newthr->regs.gs); 1055 #endif 1056 } 1057 1058 return true; 1059 } 1060 1061 #define ROUNDUP(x, y) ((((x)+((y)-1))/(y))*(y)) 1062 1063 // read NT_PRSTATUS entries from core NOTE segment 1064 static bool core_handle_note(struct ps_prochandle* ph, ELF_PHDR* note_phdr) { 1065 char* buf = NULL; 1066 char* p = NULL; 1067 size_t size = note_phdr->p_filesz; 1068 1069 // we are interested in just prstatus entries. we will ignore the rest. 1070 // Advance the seek pointer to the start of the PT_NOTE data 1071 if (lseek(ph->core->core_fd, note_phdr->p_offset, SEEK_SET) == (off_t)-1) { 1072 print_debug("failed to lseek to PT_NOTE data\n"); 1073 return false; 1074 } 1075 1076 // Now process the PT_NOTE structures. Each one is preceded by 1077 // an Elf{32/64}_Nhdr structure describing its type and size. 1078 if ( (buf = (char*) malloc(size)) == NULL) { 1079 print_debug("can't allocate memory for reading core notes\n"); 1080 goto err; 1081 } 1082 1083 // read notes into buffer 1084 if (read(ph->core->core_fd, buf, size) != size) { 1085 print_debug("failed to read notes, core file must have been truncated\n"); 1086 goto err; 1087 } 1088 1089 p = buf; 1090 while (p < buf + size) { 1091 ELF_NHDR* notep = (ELF_NHDR*) p; 1092 char* descdata = p + sizeof(ELF_NHDR) + ROUNDUP(notep->n_namesz, 4); 1093 print_debug("Note header with n_type = %d and n_descsz = %u\n", 1094 notep->n_type, notep->n_descsz); 1095 1096 if (notep->n_type == NT_PRSTATUS) { 1097 if (core_handle_prstatus(ph, descdata, notep->n_descsz) != true) { 1098 return false; 1099 } 1100 } 1101 p = descdata + ROUNDUP(notep->n_descsz, 4); 1102 } 1103 1104 free(buf); 1105 return true; 1106 1107 err: 1108 if (buf) free(buf); 1109 return false; 1110 } 1111 1112 // read all segments from core file 1113 static bool read_core_segments(struct ps_prochandle* ph, ELF_EHDR* core_ehdr) { 1114 int i = 0; 1115 ELF_PHDR* phbuf = NULL; 1116 ELF_PHDR* core_php = NULL; 1117 1118 if ((phbuf = read_program_header_table(ph->core->core_fd, core_ehdr)) == NULL) 1119 return false; 1120 1121 /* 1122 * Now iterate through the program headers in the core file. 1123 * We're interested in two types of Phdrs: PT_NOTE (which 1124 * contains a set of saved /proc structures), and PT_LOAD (which 1125 * represents a memory mapping from the process's address space). 1126 * 1127 * Difference b/w Solaris PT_NOTE and BSD PT_NOTE: 1128 * 1129 * In Solaris there are two PT_NOTE segments the first PT_NOTE (if present) 1130 * contains /proc structs in the pre-2.6 unstructured /proc format. the last 1131 * PT_NOTE has data in new /proc format. 1132 * 1133 * In Solaris, there is only one pstatus (process status). pstatus contains 1134 * integer register set among other stuff. For each LWP, we have one lwpstatus 1135 * entry that has integer regset for that LWP. 1136 * 1137 * Linux threads are actually 'clone'd processes. To support core analysis 1138 * of "multithreaded" process, Linux creates more than one pstatus (called 1139 * "prstatus") entry in PT_NOTE. Each prstatus entry has integer regset for one 1140 * "thread". Please refer to Linux kernel src file 'fs/binfmt_elf.c', in particular 1141 * function "elf_core_dump". 1142 */ 1143 1144 for (core_php = phbuf, i = 0; i < core_ehdr->e_phnum; i++) { 1145 switch (core_php->p_type) { 1146 case PT_NOTE: 1147 if (core_handle_note(ph, core_php) != true) { 1148 goto err; 1149 } 1150 break; 1151 1152 case PT_LOAD: { 1153 if (core_php->p_filesz != 0) { 1154 if (add_map_info(ph, ph->core->core_fd, core_php->p_offset, 1155 core_php->p_vaddr, core_php->p_filesz) == NULL) goto err; 1156 } 1157 break; 1158 } 1159 } 1160 1161 core_php++; 1162 } 1163 1164 free(phbuf); 1165 return true; 1166 err: 1167 free(phbuf); 1168 return false; 1169 } 1170 1171 // read segments of a shared object 1172 static bool read_lib_segments(struct ps_prochandle* ph, int lib_fd, ELF_EHDR* lib_ehdr, uintptr_t lib_base) { 1173 int i = 0; 1174 ELF_PHDR* phbuf; 1175 ELF_PHDR* lib_php = NULL; 1176 1177 if ((phbuf = read_program_header_table(lib_fd, lib_ehdr)) == NULL) 1178 return false; 1179 1180 // we want to process only PT_LOAD segments that are not writable. 1181 // i.e., text segments. The read/write/exec (data) segments would 1182 // have been already added from core file segments. 1183 for (lib_php = phbuf, i = 0; i < lib_ehdr->e_phnum; i++) { 1184 if ((lib_php->p_type == PT_LOAD) && !(lib_php->p_flags & PF_W) && (lib_php->p_filesz != 0)) { 1185 if (add_map_info(ph, lib_fd, lib_php->p_offset, lib_php->p_vaddr + lib_base, lib_php->p_filesz) == NULL) 1186 goto err; 1187 } 1188 lib_php++; 1189 } 1190 1191 free(phbuf); 1192 return true; 1193 err: 1194 free(phbuf); 1195 return false; 1196 } 1197 1198 // process segments from interpreter (ld-elf.so.1) 1199 static bool read_interp_segments(struct ps_prochandle* ph) { 1200 ELF_EHDR interp_ehdr; 1201 1202 if (read_elf_header(ph->core->interp_fd, &interp_ehdr) != true) { 1203 print_debug("interpreter is not a valid ELF file\n"); 1204 return false; 1205 } 1206 1207 if (read_lib_segments(ph, ph->core->interp_fd, &interp_ehdr, ph->core->ld_base_addr) != true) { 1208 print_debug("can't read segments of interpreter\n"); 1209 return false; 1210 } 1211 1212 return true; 1213 } 1214 1215 // process segments of a a.out 1216 static bool read_exec_segments(struct ps_prochandle* ph, ELF_EHDR* exec_ehdr) { 1217 int i = 0; 1218 ELF_PHDR* phbuf = NULL; 1219 ELF_PHDR* exec_php = NULL; 1220 1221 if ((phbuf = read_program_header_table(ph->core->exec_fd, exec_ehdr)) == NULL) 1222 return false; 1223 1224 for (exec_php = phbuf, i = 0; i < exec_ehdr->e_phnum; i++) { 1225 switch (exec_php->p_type) { 1226 1227 // add mappings for PT_LOAD segments 1228 case PT_LOAD: { 1229 // add only non-writable segments of non-zero filesz 1230 if (!(exec_php->p_flags & PF_W) && exec_php->p_filesz != 0) { 1231 if (add_map_info(ph, ph->core->exec_fd, exec_php->p_offset, exec_php->p_vaddr, exec_php->p_filesz) == NULL) goto err; 1232 } 1233 break; 1234 } 1235 1236 // read the interpreter and it's segments 1237 case PT_INTERP: { 1238 char interp_name[BUF_SIZE]; 1239 1240 pread(ph->core->exec_fd, interp_name, MIN(exec_php->p_filesz, BUF_SIZE), exec_php->p_offset); 1241 print_debug("ELF interpreter %s\n", interp_name); 1242 // read interpreter segments as well 1243 if ((ph->core->interp_fd = pathmap_open(interp_name)) < 0) { 1244 print_debug("can't open runtime loader\n"); 1245 goto err; 1246 } 1247 break; 1248 } 1249 1250 // from PT_DYNAMIC we want to read address of first link_map addr 1251 case PT_DYNAMIC: { 1252 ph->core->dynamic_addr = exec_php->p_vaddr; 1253 print_debug("address of _DYNAMIC is 0x%lx\n", ph->core->dynamic_addr); 1254 break; 1255 } 1256 1257 } // switch 1258 exec_php++; 1259 } // for 1260 1261 free(phbuf); 1262 return true; 1263 err: 1264 free(phbuf); 1265 return false; 1266 } 1267 1268 #define FIRST_LINK_MAP_OFFSET offsetof(struct r_debug, r_map) 1269 #define LD_BASE_OFFSET offsetof(struct r_debug, r_ldbase) 1270 #define LINK_MAP_ADDR_OFFSET offsetof(struct link_map, l_addr) 1271 #define LINK_MAP_NAME_OFFSET offsetof(struct link_map, l_name) 1272 #define LINK_MAP_NEXT_OFFSET offsetof(struct link_map, l_next) 1273 1274 // read shared library info from runtime linker's data structures. 1275 // This work is done by librtlb_db in Solaris 1276 static bool read_shared_lib_info(struct ps_prochandle* ph) { 1277 uintptr_t addr = ph->core->dynamic_addr; 1278 uintptr_t debug_base; 1279 uintptr_t first_link_map_addr; 1280 uintptr_t ld_base_addr; 1281 uintptr_t link_map_addr; 1282 uintptr_t lib_base_diff; 1283 uintptr_t lib_base; 1284 uintptr_t lib_name_addr; 1285 char lib_name[BUF_SIZE]; 1286 ELF_DYN dyn; 1287 ELF_EHDR elf_ehdr; 1288 int lib_fd; 1289 1290 // _DYNAMIC has information of the form 1291 // [tag] [data] [tag] [data] ..... 1292 // Both tag and data are pointer sized. 1293 // We look for dynamic info with DT_DEBUG. This has shared object info. 1294 // refer to struct r_debug in link.h 1295 1296 dyn.d_tag = DT_NULL; 1297 while (dyn.d_tag != DT_DEBUG) { 1298 if (ps_pread(ph, (psaddr_t) addr, &dyn, sizeof(ELF_DYN)) != PS_OK) { 1299 print_debug("can't read debug info from _DYNAMIC\n"); 1300 return false; 1301 } 1302 addr += sizeof(ELF_DYN); 1303 } 1304 1305 // we have got Dyn entry with DT_DEBUG 1306 debug_base = dyn.d_un.d_ptr; 1307 // at debug_base we have struct r_debug. This has first link map in r_map field 1308 if (ps_pread(ph, (psaddr_t) debug_base + FIRST_LINK_MAP_OFFSET, 1309 &first_link_map_addr, sizeof(uintptr_t)) != PS_OK) { 1310 print_debug("can't read first link map address\n"); 1311 return false; 1312 } 1313 1314 // read ld_base address from struct r_debug 1315 // XXX: There is no r_ldbase member on BSD 1316 /* 1317 if (ps_pread(ph, (psaddr_t) debug_base + LD_BASE_OFFSET, &ld_base_addr, 1318 sizeof(uintptr_t)) != PS_OK) { 1319 print_debug("can't read ld base address\n"); 1320 return false; 1321 } 1322 ph->core->ld_base_addr = ld_base_addr; 1323 */ 1324 ph->core->ld_base_addr = 0; 1325 1326 print_debug("interpreter base address is 0x%lx\n", ld_base_addr); 1327 1328 // now read segments from interp (i.e ld-elf.so.1) 1329 if (read_interp_segments(ph) != true) 1330 return false; 1331 1332 // after adding interpreter (ld.so) mappings sort again 1333 if (sort_map_array(ph) != true) 1334 return false; 1335 1336 print_debug("first link map is at 0x%lx\n", first_link_map_addr); 1337 1338 link_map_addr = first_link_map_addr; 1339 while (link_map_addr != 0) { 1340 // read library base address of the .so. Note that even though <sys/link.h> calls 1341 // link_map->l_addr as "base address", this is * not * really base virtual 1342 // address of the shared object. This is actually the difference b/w the virtual 1343 // address mentioned in shared object and the actual virtual base where runtime 1344 // linker loaded it. We use "base diff" in read_lib_segments call below. 1345 1346 if (ps_pread(ph, (psaddr_t) link_map_addr + LINK_MAP_ADDR_OFFSET, 1347 &lib_base_diff, sizeof(uintptr_t)) != PS_OK) { 1348 print_debug("can't read shared object base address diff\n"); 1349 return false; 1350 } 1351 1352 // read address of the name 1353 if (ps_pread(ph, (psaddr_t) link_map_addr + LINK_MAP_NAME_OFFSET, 1354 &lib_name_addr, sizeof(uintptr_t)) != PS_OK) { 1355 print_debug("can't read address of shared object name\n"); 1356 return false; 1357 } 1358 1359 // read name of the shared object 1360 if (read_string(ph, (uintptr_t) lib_name_addr, lib_name, sizeof(lib_name)) != true) { 1361 print_debug("can't read shared object name\n"); 1362 return false; 1363 } 1364 1365 if (lib_name[0] != '\0') { 1366 // ignore empty lib names 1367 lib_fd = pathmap_open(lib_name); 1368 1369 if (lib_fd < 0) { 1370 print_debug("can't open shared object %s\n", lib_name); 1371 // continue with other libraries... 1372 } else { 1373 if (read_elf_header(lib_fd, &elf_ehdr)) { 1374 lib_base = lib_base_diff + find_base_address(lib_fd, &elf_ehdr); 1375 print_debug("reading library %s @ 0x%lx [ 0x%lx ]\n", 1376 lib_name, lib_base, lib_base_diff); 1377 // while adding library mappings we need to use "base difference". 1378 if (! read_lib_segments(ph, lib_fd, &elf_ehdr, lib_base_diff)) { 1379 print_debug("can't read shared object's segments\n"); 1380 close(lib_fd); 1381 return false; 1382 } 1383 add_lib_info_fd(ph, lib_name, lib_fd, lib_base); 1384 // Map info is added for the library (lib_name) so 1385 // we need to re-sort it before calling the p_pdread. 1386 if (sort_map_array(ph) != true) 1387 return false; 1388 } else { 1389 print_debug("can't read ELF header for shared object %s\n", lib_name); 1390 close(lib_fd); 1391 // continue with other libraries... 1392 } 1393 } 1394 } 1395 1396 // read next link_map address 1397 if (ps_pread(ph, (psaddr_t) link_map_addr + LINK_MAP_NEXT_OFFSET, 1398 &link_map_addr, sizeof(uintptr_t)) != PS_OK) { 1399 print_debug("can't read next link in link_map\n"); 1400 return false; 1401 } 1402 } 1403 1404 return true; 1405 } 1406 1407 // the one and only one exposed stuff from this file 1408 struct ps_prochandle* Pgrab_core(const char* exec_file, const char* core_file) { 1409 ELF_EHDR core_ehdr; 1410 ELF_EHDR exec_ehdr; 1411 1412 struct ps_prochandle* ph = (struct ps_prochandle*) calloc(1, sizeof(struct ps_prochandle)); 1413 if (ph == NULL) { 1414 print_debug("cant allocate ps_prochandle\n"); 1415 return NULL; 1416 } 1417 1418 if ((ph->core = (struct core_data*) calloc(1, sizeof(struct core_data))) == NULL) { 1419 free(ph); 1420 print_debug("can't allocate ps_prochandle\n"); 1421 return NULL; 1422 } 1423 1424 // initialize ph 1425 ph->ops = &core_ops; 1426 ph->core->core_fd = -1; 1427 ph->core->exec_fd = -1; 1428 ph->core->interp_fd = -1; 1429 1430 print_debug("exec: %s core: %s", exec_file, core_file); 1431 1432 // open the core file 1433 if ((ph->core->core_fd = open(core_file, O_RDONLY)) < 0) { 1434 print_debug("can't open core file\n"); 1435 goto err; 1436 } 1437 1438 // read core file ELF header 1439 if (read_elf_header(ph->core->core_fd, &core_ehdr) != true || core_ehdr.e_type != ET_CORE) { 1440 print_debug("core file is not a valid ELF ET_CORE file\n"); 1441 goto err; 1442 } 1443 1444 if ((ph->core->exec_fd = open(exec_file, O_RDONLY)) < 0) { 1445 print_debug("can't open executable file\n"); 1446 goto err; 1447 } 1448 1449 if (read_elf_header(ph->core->exec_fd, &exec_ehdr) != true || exec_ehdr.e_type != ET_EXEC) { 1450 print_debug("executable file is not a valid ELF ET_EXEC file\n"); 1451 goto err; 1452 } 1453 1454 // process core file segments 1455 if (read_core_segments(ph, &core_ehdr) != true) 1456 goto err; 1457 1458 // process exec file segments 1459 if (read_exec_segments(ph, &exec_ehdr) != true) 1460 goto err; 1461 1462 // exec file is also treated like a shared object for symbol search 1463 if (add_lib_info_fd(ph, exec_file, ph->core->exec_fd, 1464 (uintptr_t)0 + find_base_address(ph->core->exec_fd, &exec_ehdr)) == NULL) 1465 goto err; 1466 1467 // allocate and sort maps into map_array, we need to do this 1468 // here because read_shared_lib_info needs to read from debuggee 1469 // address space 1470 if (sort_map_array(ph) != true) 1471 goto err; 1472 1473 if (read_shared_lib_info(ph) != true) 1474 goto err; 1475 1476 // sort again because we have added more mappings from shared objects 1477 if (sort_map_array(ph) != true) 1478 goto err; 1479 1480 if (init_classsharing_workaround(ph) != true) 1481 goto err; 1482 1483 print_debug("Leave Pgrab_core\n"); 1484 return ph; 1485 1486 err: 1487 Prelease(ph); 1488 return NULL; 1489 } 1490 1491 #endif // __APPLE__