1 /* BFD back-end for CISCO crash dumps. 2 Copyright 1994, 1997, 1999, 2000, 2001, 2002, 2004, 2005, 2006, 2007, 2010 3 Free Software Foundation, Inc. 4 5 This file is part of BFD, the Binary File Descriptor library. 6 7 This program is free software; you can redistribute it and/or modify 8 it under the terms of the GNU General Public License as published by 9 the Free Software Foundation; either version 3 of the License, or 10 (at your option) any later version. 11 12 This program is distributed in the hope that it will be useful, 13 but WITHOUT ANY WARRANTY; without even the implied warranty of 14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 15 GNU General Public License for more details. 16 17 You should have received a copy of the GNU General Public License 18 along with this program; if not, write to the Free Software 19 Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, 20 MA 02110-1301, USA. */ 21 22 #include "sysdep.h" 23 #include "bfd.h" 24 #include "libbfd.h" 25 /* core_file_failing_signal returns a host signal (this probably should 26 be fixed). */ 27 #include <signal.h> 28 29 /* for MSVC builds */ 30 #ifndef SIGTRAP 31 # define SIGTRAP 5 32 #endif 33 #ifndef SIGEMT 34 # define SIGEMT 6 35 #endif 36 #ifndef SIGBUS 37 # define SIGBUS 10 38 #endif 39 40 int crash_info_locs[] = { 41 0x0250, /* mips, ppc, x86, i960 */ 42 0x0400, /* m68k, mips, x86, i960 */ 43 0x0FFC, /* m68k, mips, ppc, x86, i960 */ 44 0x3000, /* ppc */ 45 0x4FFC, /* m68k */ 46 -1 47 }; 48 49 #define CRASH_MAGIC 0xdead1234 50 #define MASK_ADDR(x) ((x) & 0x0fffffff) /* Mask crash info address */ 51 52 typedef enum { 53 CRASH_REASON_NOTCRASHED = 0, 54 CRASH_REASON_EXCEPTION = 1, 55 CRASH_REASON_CORRUPT = 2, 56 } crashreason; 57 58 typedef struct { 59 char magic[4]; /* Magic number */ 60 char version[4]; /* Version number */ 61 char reason[4]; /* Crash reason */ 62 char cpu_vector[4]; /* CPU vector for exceptions */ 63 char registers[4]; /* Pointer to saved registers */ 64 char rambase[4]; /* Base of RAM (not in V1 crash info) */ 65 char textbase[4]; /* Base of .text section (not in V3 crash info) */ 66 char database[4]; /* Base of .data section (not in V3 crash info) */ 67 char bssbase[4]; /* Base of .bss section (not in V3 crash info) */ 68 } crashinfo_external; 69 70 struct cisco_core_struct 71 { 72 int sig; 73 }; 74 75 static const bfd_target *cisco_core_file_validate PARAMS ((bfd *, int)); 76 static const bfd_target *cisco_core_file_p PARAMS ((bfd *)); 77 char *cisco_core_file_failing_command PARAMS ((bfd *)); 78 int cisco_core_file_failing_signal PARAMS ((bfd *)); 79 #define cisco_core_file_matches_executable_p generic_core_file_matches_executable_p 80 #define cisco_core_file_pid _bfd_nocore_core_file_pid 81 82 /* Examine the file for a crash info struct at the offset given by 83 CRASH_INFO_LOC. */ 84 85 static const bfd_target * 86 cisco_core_file_validate (abfd, crash_info_loc) 87 bfd *abfd; 88 int crash_info_loc; 89 { 90 char buf[4]; 91 unsigned int crashinfo_offset; 92 crashinfo_external crashinfo; 93 bfd_size_type nread; 94 unsigned int magic; 95 unsigned int version; 96 unsigned int rambase; 97 sec_ptr asect; 98 struct stat statbuf; 99 bfd_size_type amt; 100 flagword flags; 101 102 if (bfd_seek (abfd, (file_ptr) crash_info_loc, SEEK_SET) != 0) 103 return NULL; 104 105 nread = bfd_bread (buf, (bfd_size_type) 4, abfd); 106 if (nread != 4) 107 { 108 if (bfd_get_error () != bfd_error_system_call) 109 bfd_set_error (bfd_error_wrong_format); 110 return NULL; 111 } 112 crashinfo_offset = MASK_ADDR (bfd_get_32 (abfd, buf)); 113 114 if (bfd_seek (abfd, (file_ptr) crashinfo_offset, SEEK_SET) != 0) 115 { 116 /* Most likely we failed because of a bogus (huge) offset */ 117 bfd_set_error (bfd_error_wrong_format); 118 return NULL; 119 } 120 121 nread = bfd_bread (&crashinfo, (bfd_size_type) sizeof (crashinfo), abfd); 122 if (nread != sizeof (crashinfo)) 123 { 124 if (bfd_get_error () != bfd_error_system_call) 125 bfd_set_error (bfd_error_wrong_format); 126 return NULL; 127 } 128 129 if (bfd_stat (abfd, &statbuf) < 0) 130 { 131 bfd_set_error (bfd_error_system_call); 132 return NULL; 133 } 134 135 magic = bfd_get_32 (abfd, crashinfo.magic); 136 if (magic != CRASH_MAGIC) 137 { 138 bfd_set_error (bfd_error_wrong_format); 139 return NULL; 140 } 141 142 version = bfd_get_32 (abfd, crashinfo.version); 143 if (version == 0) 144 { 145 bfd_set_error (bfd_error_wrong_format); 146 return NULL; 147 } 148 else if (version == 1) 149 { 150 /* V1 core dumps don't specify the dump base, assume 0 */ 151 rambase = 0; 152 } 153 else 154 { 155 rambase = bfd_get_32 (abfd, crashinfo.rambase); 156 } 157 158 /* OK, we believe you. You're a core file. */ 159 160 amt = sizeof (struct cisco_core_struct); 161 abfd->tdata.cisco_core_data = (struct cisco_core_struct *) bfd_zmalloc (amt); 162 if (abfd->tdata.cisco_core_data == NULL) 163 return NULL; 164 165 switch ((crashreason) bfd_get_32 (abfd, crashinfo.reason)) 166 { 167 case CRASH_REASON_NOTCRASHED: 168 /* Crash file probably came from write core. */ 169 abfd->tdata.cisco_core_data->sig = 0; 170 break; 171 case CRASH_REASON_CORRUPT: 172 /* The crash context area was corrupt -- proceed with caution. 173 We have no way of passing this information back to the caller. */ 174 abfd->tdata.cisco_core_data->sig = 0; 175 break; 176 case CRASH_REASON_EXCEPTION: 177 /* Crash occured due to CPU exception. */ 178 179 /* This is 68k-specific; for MIPS we'll need to interpret 180 cpu_vector differently based on the target configuration 181 (since CISCO core files don't seem to have the processor 182 encoded in them). */ 183 184 switch (bfd_get_32 (abfd, crashinfo.cpu_vector)) 185 { 186 /* bus error */ 187 case 2 : abfd->tdata.cisco_core_data->sig = SIGBUS; break; 188 /* address error */ 189 case 3 : abfd->tdata.cisco_core_data->sig = SIGBUS; break; 190 /* illegal instruction */ 191 case 4 : abfd->tdata.cisco_core_data->sig = SIGILL; break; 192 /* zero divide */ 193 case 5 : abfd->tdata.cisco_core_data->sig = SIGFPE; break; 194 /* chk instruction */ 195 case 6 : abfd->tdata.cisco_core_data->sig = SIGFPE; break; 196 /* trapv instruction */ 197 case 7 : abfd->tdata.cisco_core_data->sig = SIGFPE; break; 198 /* privilege violation */ 199 case 8 : abfd->tdata.cisco_core_data->sig = SIGSEGV; break; 200 /* trace trap */ 201 case 9 : abfd->tdata.cisco_core_data->sig = SIGTRAP; break; 202 /* line 1010 emulator */ 203 case 10: abfd->tdata.cisco_core_data->sig = SIGILL; break; 204 /* line 1111 emulator */ 205 case 11: abfd->tdata.cisco_core_data->sig = SIGILL; break; 206 207 /* Coprocessor protocol violation. Using a standard MMU or FPU 208 this cannot be triggered by software. Call it a SIGBUS. */ 209 case 13: abfd->tdata.cisco_core_data->sig = SIGBUS; break; 210 211 /* interrupt */ 212 case 31: abfd->tdata.cisco_core_data->sig = SIGINT; break; 213 /* breakpoint */ 214 case 33: abfd->tdata.cisco_core_data->sig = SIGTRAP; break; 215 216 /* floating point err */ 217 case 48: abfd->tdata.cisco_core_data->sig = SIGFPE; break; 218 /* floating point err */ 219 case 49: abfd->tdata.cisco_core_data->sig = SIGFPE; break; 220 /* zero divide */ 221 case 50: abfd->tdata.cisco_core_data->sig = SIGFPE; break; 222 /* underflow */ 223 case 51: abfd->tdata.cisco_core_data->sig = SIGFPE; break; 224 /* operand error */ 225 case 52: abfd->tdata.cisco_core_data->sig = SIGFPE; break; 226 /* overflow */ 227 case 53: abfd->tdata.cisco_core_data->sig = SIGFPE; break; 228 /* NAN */ 229 case 54: abfd->tdata.cisco_core_data->sig = SIGFPE; break; 230 default: 231 #ifndef SIGEMT 232 #define SIGEMT SIGTRAP 233 #endif 234 /* "software generated"*/ 235 abfd->tdata.cisco_core_data->sig = SIGEMT; 236 } 237 break; 238 default: 239 /* Unknown crash reason. */ 240 abfd->tdata.cisco_core_data->sig = 0; 241 break; 242 } 243 244 /* Create a ".data" section that maps the entire file, which is 245 essentially a dump of the target system's RAM. */ 246 247 flags = SEC_ALLOC | SEC_LOAD | SEC_HAS_CONTENTS; 248 asect = bfd_make_section_anyway_with_flags (abfd, ".data", flags); 249 if (asect == NULL) 250 goto error_return; 251 /* The size of memory is the size of the core file itself. */ 252 asect->size = statbuf.st_size; 253 asect->vma = rambase; 254 asect->filepos = 0; 255 256 /* Create a ".crash" section to allow access to the saved 257 crash information. */ 258 259 flags = SEC_HAS_CONTENTS; 260 asect = bfd_make_section_anyway_with_flags (abfd, ".crash", flags); 261 if (asect == NULL) 262 goto error_return; 263 asect->vma = 0; 264 asect->filepos = crashinfo_offset; 265 asect->size = sizeof (crashinfo); 266 267 /* Create a ".reg" section to allow access to the saved 268 registers. */ 269 270 asect = bfd_make_section_anyway_with_flags (abfd, ".reg", flags); 271 if (asect == NULL) 272 goto error_return; 273 asect->vma = 0; 274 asect->filepos = bfd_get_32 (abfd, crashinfo.registers) - rambase; 275 /* Since we don't know the exact size of the saved register info, 276 choose a register section size that is either the remaining part 277 of the file, or 1024, whichever is smaller. */ 278 nread = statbuf.st_size - asect->filepos; 279 asect->size = (nread < 1024) ? nread : 1024; 280 281 return abfd->xvec; 282 283 /* Get here if we have already started filling out the BFD 284 and there is an error of some kind. */ 285 286 error_return: 287 bfd_release (abfd, abfd->tdata.any); 288 abfd->tdata.any = NULL; 289 bfd_section_list_clear (abfd); 290 return NULL; 291 } 292 293 static const bfd_target * 294 cisco_core_file_p (abfd) 295 bfd *abfd; 296 { 297 int *crash_info_locp; 298 const bfd_target *target = NULL; 299 300 for (crash_info_locp = crash_info_locs; 301 *crash_info_locp != -1 && target == NULL; 302 crash_info_locp++) 303 { 304 target = cisco_core_file_validate (abfd, *crash_info_locp); 305 } 306 return (target); 307 } 308 309 char * 310 cisco_core_file_failing_command (abfd) 311 bfd *abfd ATTRIBUTE_UNUSED; 312 { 313 return NULL; 314 } 315 316 int 317 cisco_core_file_failing_signal (abfd) 318 bfd *abfd ATTRIBUTE_UNUSED; 319 { 320 return abfd->tdata.cisco_core_data->sig; 321 } 322 323 extern const bfd_target cisco_core_little_vec; 324 325 const bfd_target cisco_core_big_vec = 326 { 327 "cisco-ios-core-big", 328 bfd_target_unknown_flavour, 329 BFD_ENDIAN_BIG, /* target byte order */ 330 BFD_ENDIAN_BIG, /* target headers byte order */ 331 (HAS_RELOC | EXEC_P | /* object flags */ 332 HAS_LINENO | HAS_DEBUG | 333 HAS_SYMS | HAS_LOCALS | WP_TEXT | D_PAGED), 334 (SEC_HAS_CONTENTS | SEC_ALLOC | SEC_LOAD | SEC_RELOC), /* section flags */ 335 0, /* symbol prefix */ 336 ' ', /* ar_pad_char */ 337 16, /* ar_max_namelen */ 338 bfd_getb64, bfd_getb_signed_64, bfd_putb64, 339 bfd_getb32, bfd_getb_signed_32, bfd_putb32, 340 bfd_getb16, bfd_getb_signed_16, bfd_putb16, /* data */ 341 bfd_getb64, bfd_getb_signed_64, bfd_putb64, 342 bfd_getb32, bfd_getb_signed_32, bfd_putb32, 343 bfd_getb16, bfd_getb_signed_16, bfd_putb16, /* hdrs */ 344 345 { /* bfd_check_format */ 346 _bfd_dummy_target, /* unknown format */ 347 _bfd_dummy_target, /* object file */ 348 _bfd_dummy_target, /* archive */ 349 cisco_core_file_p /* a core file */ 350 }, 351 { /* bfd_set_format */ 352 bfd_false, bfd_false, 353 bfd_false, bfd_false 354 }, 355 { /* bfd_write_contents */ 356 bfd_false, bfd_false, 357 bfd_false, bfd_false 358 }, 359 360 BFD_JUMP_TABLE_GENERIC (_bfd_generic), 361 BFD_JUMP_TABLE_COPY (_bfd_generic), 362 BFD_JUMP_TABLE_CORE (cisco), 363 BFD_JUMP_TABLE_ARCHIVE (_bfd_noarchive), 364 BFD_JUMP_TABLE_SYMBOLS (_bfd_nosymbols), 365 BFD_JUMP_TABLE_RELOCS (_bfd_norelocs), 366 BFD_JUMP_TABLE_WRITE (_bfd_generic), 367 BFD_JUMP_TABLE_LINK (_bfd_nolink), 368 BFD_JUMP_TABLE_DYNAMIC (_bfd_nodynamic), 369 370 & cisco_core_little_vec, 371 372 (PTR) 0 /* backend_data */ 373 }; 374 375 const bfd_target cisco_core_little_vec = 376 { 377 "cisco-ios-core-little", 378 bfd_target_unknown_flavour, 379 BFD_ENDIAN_LITTLE, /* target byte order */ 380 BFD_ENDIAN_LITTLE, /* target headers byte order */ 381 (HAS_RELOC | EXEC_P | /* object flags */ 382 HAS_LINENO | HAS_DEBUG | 383 HAS_SYMS | HAS_LOCALS | WP_TEXT | D_PAGED), 384 (SEC_HAS_CONTENTS | SEC_ALLOC | SEC_LOAD | SEC_RELOC), /* section flags */ 385 0, /* symbol prefix */ 386 ' ', /* ar_pad_char */ 387 16, /* ar_max_namelen */ 388 bfd_getl64, bfd_getl_signed_64, bfd_putl64, 389 bfd_getl32, bfd_getl_signed_32, bfd_putl32, 390 bfd_getl16, bfd_getl_signed_16, bfd_putl16, /* data */ 391 bfd_getl64, bfd_getl_signed_64, bfd_putl64, 392 bfd_getl32, bfd_getl_signed_32, bfd_putl32, 393 bfd_getl16, bfd_getl_signed_16, bfd_putl16, /* hdrs */ 394 395 { /* bfd_check_format */ 396 _bfd_dummy_target, /* unknown format */ 397 _bfd_dummy_target, /* object file */ 398 _bfd_dummy_target, /* archive */ 399 cisco_core_file_p /* a core file */ 400 }, 401 { /* bfd_set_format */ 402 bfd_false, bfd_false, 403 bfd_false, bfd_false 404 }, 405 { /* bfd_write_contents */ 406 bfd_false, bfd_false, 407 bfd_false, bfd_false 408 }, 409 410 BFD_JUMP_TABLE_GENERIC (_bfd_generic), 411 BFD_JUMP_TABLE_COPY (_bfd_generic), 412 BFD_JUMP_TABLE_CORE (cisco), 413 BFD_JUMP_TABLE_ARCHIVE (_bfd_noarchive), 414 BFD_JUMP_TABLE_SYMBOLS (_bfd_nosymbols), 415 BFD_JUMP_TABLE_RELOCS (_bfd_norelocs), 416 BFD_JUMP_TABLE_WRITE (_bfd_generic), 417 BFD_JUMP_TABLE_LINK (_bfd_nolink), 418 BFD_JUMP_TABLE_DYNAMIC (_bfd_nodynamic), 419 420 &cisco_core_big_vec, 421 422 (PTR) 0 /* backend_data */ 423 }; 424