1 /* BFD back-end for CISCO crash dumps. 2 Copyright (C) 1994-2016 Free Software Foundation, Inc. 3 4 This file is part of BFD, the Binary File Descriptor library. 5 6 This program is free software; you can redistribute it and/or modify 7 it under the terms of the GNU General Public License as published by 8 the Free Software Foundation; either version 3 of the License, or 9 (at your option) any later version. 10 11 This program is distributed in the hope that it will be useful, 12 but WITHOUT ANY WARRANTY; without even the implied warranty of 13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 GNU General Public License for more details. 15 16 You should have received a copy of the GNU General Public License 17 along with this program; if not, write to the Free Software 18 Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, 19 MA 02110-1301, USA. */ 20 21 #include "sysdep.h" 22 #include "bfd.h" 23 #include "libbfd.h" 24 /* core_file_failing_signal returns a host signal (this probably should 25 be fixed). */ 26 #include <signal.h> 27 28 /* for MSVC builds */ 29 #ifndef SIGTRAP 30 # define SIGTRAP 5 31 #endif 32 #ifndef SIGEMT 33 # define SIGEMT 6 34 #endif 35 #ifndef SIGBUS 36 # define SIGBUS 10 37 #endif 38 39 int crash_info_locs[] = 41 { 42 0x0250, /* mips, ppc, x86, i960 */ 43 0x0400, /* m68k, mips, x86, i960 */ 44 0x0FFC, /* m68k, mips, ppc, x86, i960 */ 45 0x3000, /* ppc */ 46 0x4FFC, /* m68k */ 47 -1 48 }; 49 50 #define CRASH_MAGIC 0xdead1234 51 #define MASK_ADDR(x) ((x) & 0x0fffffff) /* Mask crash info address */ 52 53 typedef enum 54 { 55 CRASH_REASON_NOTCRASHED = 0, 56 CRASH_REASON_EXCEPTION = 1, 57 CRASH_REASON_CORRUPT = 2, 58 } crashreason; 59 60 typedef struct 61 { 62 char magic[4]; /* Magic number */ 63 char version[4]; /* Version number */ 64 char reason[4]; /* Crash reason */ 65 char cpu_vector[4]; /* CPU vector for exceptions */ 66 char registers[4]; /* Pointer to saved registers */ 67 char rambase[4]; /* Base of RAM (not in V1 crash info) */ 68 char textbase[4]; /* Base of .text section (not in V3 crash info) */ 69 char database[4]; /* Base of .data section (not in V3 crash info) */ 70 char bssbase[4]; /* Base of .bss section (not in V3 crash info) */ 71 } crashinfo_external; 72 73 struct cisco_core_struct 74 { 75 int sig; 76 }; 77 78 #define cisco_core_file_matches_executable_p generic_core_file_matches_executable_p 79 #define cisco_core_file_pid _bfd_nocore_core_file_pid 80 81 /* 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 (bfd *abfd, int crash_info_loc) 87 { 88 char buf[4]; 89 unsigned int crashinfo_offset; 90 crashinfo_external crashinfo; 91 bfd_size_type nread; 92 unsigned int magic; 93 unsigned int version; 94 unsigned int rambase; 95 sec_ptr asect; 96 struct stat statbuf; 97 bfd_size_type amt; 98 flagword flags; 99 100 if (bfd_seek (abfd, (file_ptr) crash_info_loc, SEEK_SET) != 0) 101 return NULL; 102 103 nread = bfd_bread (buf, (bfd_size_type) 4, abfd); 104 if (nread != 4) 105 { 106 if (bfd_get_error () != bfd_error_system_call) 107 bfd_set_error (bfd_error_wrong_format); 108 return NULL; 109 } 110 crashinfo_offset = MASK_ADDR (bfd_get_32 (abfd, buf)); 111 112 if (bfd_seek (abfd, (file_ptr) crashinfo_offset, SEEK_SET) != 0) 113 { 114 /* Most likely we failed because of a bogus (huge) offset */ 115 bfd_set_error (bfd_error_wrong_format); 116 return NULL; 117 } 118 119 nread = bfd_bread (&crashinfo, (bfd_size_type) sizeof (crashinfo), abfd); 120 if (nread != sizeof (crashinfo)) 121 { 122 if (bfd_get_error () != bfd_error_system_call) 123 bfd_set_error (bfd_error_wrong_format); 124 return NULL; 125 } 126 127 if (bfd_stat (abfd, &statbuf) < 0) 128 { 129 bfd_set_error (bfd_error_system_call); 130 return NULL; 131 } 132 133 magic = bfd_get_32 (abfd, crashinfo.magic); 134 if (magic != CRASH_MAGIC) 135 { 136 bfd_set_error (bfd_error_wrong_format); 137 return NULL; 138 } 139 140 version = bfd_get_32 (abfd, crashinfo.version); 141 if (version == 0) 142 { 143 bfd_set_error (bfd_error_wrong_format); 144 return NULL; 145 } 146 else if (version == 1) 147 { 148 /* V1 core dumps don't specify the dump base, assume 0 */ 149 rambase = 0; 150 } 151 else 152 { 153 rambase = bfd_get_32 (abfd, crashinfo.rambase); 154 } 155 156 /* OK, we believe you. You're a core file. */ 157 158 amt = sizeof (struct cisco_core_struct); 159 abfd->tdata.cisco_core_data = (struct cisco_core_struct *) bfd_zmalloc (amt); 160 if (abfd->tdata.cisco_core_data == NULL) 161 return NULL; 162 163 switch ((crashreason) bfd_get_32 (abfd, crashinfo.reason)) 164 { 165 case CRASH_REASON_NOTCRASHED: 166 /* Crash file probably came from write core. */ 167 abfd->tdata.cisco_core_data->sig = 0; 168 break; 169 case CRASH_REASON_CORRUPT: 170 /* The crash context area was corrupt -- proceed with caution. 171 We have no way of passing this information back to the caller. */ 172 abfd->tdata.cisco_core_data->sig = 0; 173 break; 174 case CRASH_REASON_EXCEPTION: 175 /* Crash occured due to CPU exception. */ 176 177 /* This is 68k-specific; for MIPS we'll need to interpret 178 cpu_vector differently based on the target configuration 179 (since CISCO core files don't seem to have the processor 180 encoded in them). */ 181 182 switch (bfd_get_32 (abfd, crashinfo.cpu_vector)) 183 { 184 /* bus error */ 185 case 2 : abfd->tdata.cisco_core_data->sig = SIGBUS; break; 186 /* address error */ 187 case 3 : abfd->tdata.cisco_core_data->sig = SIGBUS; break; 188 /* illegal instruction */ 189 case 4 : abfd->tdata.cisco_core_data->sig = SIGILL; break; 190 /* zero divide */ 191 case 5 : abfd->tdata.cisco_core_data->sig = SIGFPE; break; 192 /* chk instruction */ 193 case 6 : abfd->tdata.cisco_core_data->sig = SIGFPE; break; 194 /* trapv instruction */ 195 case 7 : abfd->tdata.cisco_core_data->sig = SIGFPE; break; 196 /* privilege violation */ 197 case 8 : abfd->tdata.cisco_core_data->sig = SIGSEGV; break; 198 /* trace trap */ 199 case 9 : abfd->tdata.cisco_core_data->sig = SIGTRAP; break; 200 /* line 1010 emulator */ 201 case 10: abfd->tdata.cisco_core_data->sig = SIGILL; break; 202 /* line 1111 emulator */ 203 case 11: abfd->tdata.cisco_core_data->sig = SIGILL; break; 204 205 /* Coprocessor protocol violation. Using a standard MMU or FPU 206 this cannot be triggered by software. Call it a SIGBUS. */ 207 case 13: abfd->tdata.cisco_core_data->sig = SIGBUS; break; 208 209 /* interrupt */ 210 case 31: abfd->tdata.cisco_core_data->sig = SIGINT; break; 211 /* breakpoint */ 212 case 33: abfd->tdata.cisco_core_data->sig = SIGTRAP; break; 213 214 /* floating point err */ 215 case 48: abfd->tdata.cisco_core_data->sig = SIGFPE; break; 216 /* floating point err */ 217 case 49: abfd->tdata.cisco_core_data->sig = SIGFPE; break; 218 /* zero divide */ 219 case 50: abfd->tdata.cisco_core_data->sig = SIGFPE; break; 220 /* underflow */ 221 case 51: abfd->tdata.cisco_core_data->sig = SIGFPE; break; 222 /* operand error */ 223 case 52: abfd->tdata.cisco_core_data->sig = SIGFPE; break; 224 /* overflow */ 225 case 53: abfd->tdata.cisco_core_data->sig = SIGFPE; break; 226 /* NAN */ 227 case 54: abfd->tdata.cisco_core_data->sig = SIGFPE; break; 228 default: 229 #ifndef SIGEMT 230 #define SIGEMT SIGTRAP 231 #endif 232 /* "software generated"*/ 233 abfd->tdata.cisco_core_data->sig = SIGEMT; 234 } 235 break; 236 default: 237 /* Unknown crash reason. */ 238 abfd->tdata.cisco_core_data->sig = 0; 239 break; 240 } 241 242 /* Create a ".data" section that maps the entire file, which is 243 essentially a dump of the target system's RAM. */ 244 245 flags = SEC_ALLOC | SEC_LOAD | SEC_HAS_CONTENTS; 246 asect = bfd_make_section_anyway_with_flags (abfd, ".data", flags); 247 if (asect == NULL) 248 goto error_return; 249 /* The size of memory is the size of the core file itself. */ 250 asect->size = statbuf.st_size; 251 asect->vma = rambase; 252 asect->filepos = 0; 253 254 /* Create a ".crash" section to allow access to the saved 255 crash information. */ 256 257 flags = SEC_HAS_CONTENTS; 258 asect = bfd_make_section_anyway_with_flags (abfd, ".crash", flags); 259 if (asect == NULL) 260 goto error_return; 261 asect->vma = 0; 262 asect->filepos = crashinfo_offset; 263 asect->size = sizeof (crashinfo); 264 265 /* Create a ".reg" section to allow access to the saved 266 registers. */ 267 268 asect = bfd_make_section_anyway_with_flags (abfd, ".reg", flags); 269 if (asect == NULL) 270 goto error_return; 271 asect->vma = 0; 272 asect->filepos = bfd_get_32 (abfd, crashinfo.registers) - rambase; 273 /* Since we don't know the exact size of the saved register info, 274 choose a register section size that is either the remaining part 275 of the file, or 1024, whichever is smaller. */ 276 nread = statbuf.st_size - asect->filepos; 277 asect->size = (nread < 1024) ? nread : 1024; 278 279 return abfd->xvec; 280 281 /* Get here if we have already started filling out the BFD 282 and there is an error of some kind. */ 283 284 error_return: 285 bfd_release (abfd, abfd->tdata.any); 286 abfd->tdata.any = NULL; 287 bfd_section_list_clear (abfd); 288 return NULL; 289 } 290 291 static const bfd_target * 292 cisco_core_file_p (bfd *abfd) 293 { 294 int *crash_info_locp; 295 const bfd_target *target = NULL; 296 297 for (crash_info_locp = crash_info_locs; 298 *crash_info_locp != -1 && target == NULL; 299 crash_info_locp++) 300 { 301 target = cisco_core_file_validate (abfd, *crash_info_locp); 302 } 303 return (target); 304 } 305 306 static char * 307 cisco_core_file_failing_command (bfd *abfd ATTRIBUTE_UNUSED) 308 { 309 return NULL; 310 } 311 312 static int 313 cisco_core_file_failing_signal (bfd *abfd ATTRIBUTE_UNUSED) 314 { 315 return abfd->tdata.cisco_core_data->sig; 316 } 317 318 extern const bfd_target core_cisco_le_vec; 320 321 const bfd_target core_cisco_be_vec = 322 { 323 "cisco-ios-core-big", 324 bfd_target_unknown_flavour, 325 BFD_ENDIAN_BIG, /* target byte order */ 326 BFD_ENDIAN_BIG, /* target headers byte order */ 327 (HAS_RELOC | EXEC_P | /* object flags */ 328 HAS_LINENO | HAS_DEBUG | 329 HAS_SYMS | HAS_LOCALS | WP_TEXT | D_PAGED), 330 (SEC_HAS_CONTENTS | SEC_ALLOC | SEC_LOAD | SEC_RELOC), /* section flags */ 331 0, /* symbol prefix */ 332 ' ', /* ar_pad_char */ 333 16, /* ar_max_namelen */ 334 0, /* match priority. */ 335 bfd_getb64, bfd_getb_signed_64, bfd_putb64, 336 bfd_getb32, bfd_getb_signed_32, bfd_putb32, 337 bfd_getb16, bfd_getb_signed_16, bfd_putb16, /* data */ 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, /* hdrs */ 341 342 { /* bfd_check_format */ 343 _bfd_dummy_target, /* unknown format */ 344 _bfd_dummy_target, /* object file */ 345 _bfd_dummy_target, /* archive */ 346 cisco_core_file_p /* a core file */ 347 }, 348 { /* bfd_set_format */ 349 bfd_false, bfd_false, 350 bfd_false, bfd_false 351 }, 352 { /* bfd_write_contents */ 353 bfd_false, bfd_false, 354 bfd_false, bfd_false 355 }, 356 357 BFD_JUMP_TABLE_GENERIC (_bfd_generic), 358 BFD_JUMP_TABLE_COPY (_bfd_generic), 359 BFD_JUMP_TABLE_CORE (cisco), 360 BFD_JUMP_TABLE_ARCHIVE (_bfd_noarchive), 361 BFD_JUMP_TABLE_SYMBOLS (_bfd_nosymbols), 362 BFD_JUMP_TABLE_RELOCS (_bfd_norelocs), 363 BFD_JUMP_TABLE_WRITE (_bfd_generic), 364 BFD_JUMP_TABLE_LINK (_bfd_nolink), 365 BFD_JUMP_TABLE_DYNAMIC (_bfd_nodynamic), 366 367 & core_cisco_le_vec, 368 369 NULL /* backend_data */ 370 }; 371 372 const bfd_target core_cisco_le_vec = 373 { 374 "cisco-ios-core-little", 375 bfd_target_unknown_flavour, 376 BFD_ENDIAN_LITTLE, /* target byte order */ 377 BFD_ENDIAN_LITTLE, /* target headers byte order */ 378 (HAS_RELOC | EXEC_P | /* object flags */ 379 HAS_LINENO | HAS_DEBUG | 380 HAS_SYMS | HAS_LOCALS | WP_TEXT | D_PAGED), 381 (SEC_HAS_CONTENTS | SEC_ALLOC | SEC_LOAD | SEC_RELOC), /* section flags */ 382 0, /* symbol prefix */ 383 ' ', /* ar_pad_char */ 384 16, /* ar_max_namelen */ 385 0, /* match_priority */ 386 bfd_getl64, bfd_getl_signed_64, bfd_putl64, 387 bfd_getl32, bfd_getl_signed_32, bfd_putl32, 388 bfd_getl16, bfd_getl_signed_16, bfd_putl16, /* data */ 389 bfd_getl64, bfd_getl_signed_64, bfd_putl64, 390 bfd_getl32, bfd_getl_signed_32, bfd_putl32, 391 bfd_getl16, bfd_getl_signed_16, bfd_putl16, /* hdrs */ 392 393 { /* bfd_check_format */ 394 _bfd_dummy_target, /* unknown format */ 395 _bfd_dummy_target, /* object file */ 396 _bfd_dummy_target, /* archive */ 397 cisco_core_file_p /* a core file */ 398 }, 399 { /* bfd_set_format */ 400 bfd_false, bfd_false, 401 bfd_false, bfd_false 402 }, 403 { /* bfd_write_contents */ 404 bfd_false, bfd_false, 405 bfd_false, bfd_false 406 }, 407 408 BFD_JUMP_TABLE_GENERIC (_bfd_generic), 409 BFD_JUMP_TABLE_COPY (_bfd_generic), 410 BFD_JUMP_TABLE_CORE (cisco), 411 BFD_JUMP_TABLE_ARCHIVE (_bfd_noarchive), 412 BFD_JUMP_TABLE_SYMBOLS (_bfd_nosymbols), 413 BFD_JUMP_TABLE_RELOCS (_bfd_norelocs), 414 BFD_JUMP_TABLE_WRITE (_bfd_generic), 415 BFD_JUMP_TABLE_LINK (_bfd_nolink), 416 BFD_JUMP_TABLE_DYNAMIC (_bfd_nodynamic), 417 418 &core_cisco_be_vec, 419 420 NULL /* backend_data */ 421 }; 422
