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