bfd/cisco-core.c

   1 /* BFD back-end for CISCO crash dumps.
   2    Copyright 1994, 1997, 1999, 2000, 2001 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 2 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
  19
  20 #include "bfd.h"
  21 #include "sysdep.h"
  22 #include "libbfd.h"
  23 /* core_file_failing_signal returns a host signal (this probably should
  24    be fixed).  */
  25 #include <signal.h>
  26
  27 /* for MSVC builds */
  28 #ifndef SIGTRAP
  29 # define SIGTRAP 5
  30 #endif
  31 #ifndef SIGEMT
  32 # define SIGEMT 6
  33 #endif
  34 #ifndef SIGBUS
  35 # define SIGBUS 10
  36 #endif
  37 \f
  38 int crash_info_locs[] = {
  39   0x0250,       /* mips, ppc, x86, i960 */
  40   0x0400,       /* m68k, mips, x86, i960 */
  41   0x0FFC,       /* m68k, mips, ppc, x86, i960 */
  42   0x3000,       /* ppc */
  43   0x4FFC,       /* m68k */
  44   -1
  45 };
  46
  47 #define CRASH_MAGIC     0xdead1234
  48 #define MASK_ADDR(x)    ((x) & 0x0fffffff)      /* Mask crash info address */
  49
  50 typedef enum {
  51     CRASH_REASON_NOTCRASHED = 0,
  52     CRASH_REASON_EXCEPTION = 1,
  53     CRASH_REASON_CORRUPT = 2,
  54 } crashreason;
  55
  56 typedef struct {
  57   char magic[4];                /* Magic number */
  58   char version[4];              /* Version number */
  59   char reason[4];               /* Crash reason */
  60   char cpu_vector[4];           /* CPU vector for exceptions */
  61   char registers[4];            /* Pointer to saved registers */
  62   char rambase[4];              /* Base of RAM (not in V1 crash info) */
  63   char textbase[4];             /* Base of .text section (not in V3 crash info) */
  64   char database[4];             /* Base of .data section (not in V3 crash info) */
  65   char bssbase[4];              /* Base of .bss section (not in V3 crash info) */
  66 } crashinfo_external;
  67
  68 struct cisco_core_struct
  69 {
  70   int sig;
  71 };
  72
  73 static const bfd_target *cisco_core_file_validate PARAMS ((bfd *, int));
  74 static const bfd_target *cisco_core_file_p PARAMS ((bfd *));
  75 char *cisco_core_file_failing_command PARAMS ((bfd *));
  76 int cisco_core_file_failing_signal PARAMS ((bfd *));
  77 boolean cisco_core_file_matches_executable_p PARAMS ((bfd *, bfd *));
  78 \f
  79 /* Examine the file for a crash info struct at the offset given by
  80    CRASH_INFO_LOC.  */
  81
  82 static const bfd_target *
  83 cisco_core_file_validate (abfd, crash_info_loc)
  84      bfd *abfd;
  85      int crash_info_loc;
  86 {
  87   char buf[4];
  88   unsigned int crashinfo_offset;
  89   crashinfo_external crashinfo;
  90   int nread;
  91   unsigned int magic;
  92   unsigned int version;
  93   unsigned int rambase;
  94   sec_ptr asect;
  95   struct stat statbuf;
  96   bfd_size_type amt;
  97
  98   if (bfd_seek (abfd, (file_ptr) crash_info_loc, SEEK_SET) != 0)
  99     return NULL;
 100
 101   nread = bfd_bread (buf, (bfd_size_type) 4, abfd);
 102   if (nread != 4)
 103     {
 104       if (bfd_get_error () != bfd_error_system_call)
 105         bfd_set_error (bfd_error_wrong_format);
 106       return NULL;
 107     }
 108   crashinfo_offset = MASK_ADDR (bfd_get_32 (abfd, buf));
 109
 110   if (bfd_seek (abfd, (file_ptr) crashinfo_offset, SEEK_SET) != 0)
 111     {
 112       /* Most likely we failed because of a bogus (huge) offset */
 113       bfd_set_error (bfd_error_wrong_format);
 114       return NULL;
 115     }
 116
 117   nread = bfd_bread (&crashinfo, (bfd_size_type) sizeof (crashinfo), abfd);
 118   if (nread != sizeof (crashinfo))
 119     {
 120       if (bfd_get_error () != bfd_error_system_call)
 121         bfd_set_error (bfd_error_wrong_format);
 122       return NULL;
 123     }
 124
 125   if (bfd_stat (abfd, &statbuf) < 0)
 126     {
 127       bfd_set_error (bfd_error_system_call);
 128       return NULL;
 129     }
 130
 131   magic = bfd_get_32 (abfd, crashinfo.magic);
 132   if (magic != CRASH_MAGIC)
 133     {
 134       bfd_set_error (bfd_error_wrong_format);
 135       return NULL;
 136     }
 137
 138   version = bfd_get_32 (abfd, crashinfo.version);
 139   if (version == 0)
 140     {
 141       bfd_set_error (bfd_error_wrong_format);
 142       return NULL;
 143     }
 144   else if (version == 1)
 145     {
 146       /* V1 core dumps don't specify the dump base, assume 0 */
 147       rambase = 0;
 148     }
 149   else
 150     {
 151       rambase = bfd_get_32 (abfd, crashinfo.rambase);
 152     }
 153
 154   /* OK, we believe you.  You're a core file.  */
 155
 156   amt = sizeof (struct cisco_core_struct);
 157   abfd->tdata.cisco_core_data = (struct cisco_core_struct *) bfd_zmalloc (amt);
 158   if (abfd->tdata.cisco_core_data == NULL)
 159     return NULL;
 160
 161   switch ((crashreason) bfd_get_32 (abfd, crashinfo.reason))
 162     {
 163     case CRASH_REASON_NOTCRASHED:
 164       /* Crash file probably came from write core.  */
 165       abfd->tdata.cisco_core_data->sig = 0;
 166       break;
 167     case CRASH_REASON_CORRUPT:
 168       /* The crash context area was corrupt -- proceed with caution.
 169          We have no way of passing this information back to the caller.  */
 170       abfd->tdata.cisco_core_data->sig = 0;
 171       break;
 172     case CRASH_REASON_EXCEPTION:
 173       /* Crash occured due to CPU exception.  */
 174
 175       /* This is 68k-specific; for MIPS we'll need to interpret
 176          cpu_vector differently based on the target configuration
 177          (since CISCO core files don't seem to have the processor
 178          encoded in them).  */
 179
 180       switch (bfd_get_32 (abfd, crashinfo.cpu_vector))
 181         {
 182            /* bus error           */
 183         case 2 : abfd->tdata.cisco_core_data->sig = SIGBUS; break;
 184            /* address error       */
 185         case 3 : abfd->tdata.cisco_core_data->sig = SIGBUS; break;
 186            /* illegal instruction */
 187         case 4 : abfd->tdata.cisco_core_data->sig = SIGILL;  break;
 188            /* zero divide         */
 189         case 5 : abfd->tdata.cisco_core_data->sig = SIGFPE;  break;
 190            /* chk instruction     */
 191         case 6 : abfd->tdata.cisco_core_data->sig = SIGFPE; break;
 192            /* trapv instruction   */
 193         case 7 : abfd->tdata.cisco_core_data->sig = SIGFPE; break;
 194            /* privilege violation */
 195         case 8 : abfd->tdata.cisco_core_data->sig = SIGSEGV; break;
 196            /* trace trap          */
 197         case 9 : abfd->tdata.cisco_core_data->sig = SIGTRAP;  break;
 198            /* line 1010 emulator  */
 199         case 10: abfd->tdata.cisco_core_data->sig = SIGILL;  break;
 200            /* line 1111 emulator  */
 201         case 11: abfd->tdata.cisco_core_data->sig = SIGILL;  break;
 202
 203           /* Coprocessor protocol violation.  Using a standard MMU or FPU
 204              this cannot be triggered by software.  Call it a SIGBUS.  */
 205         case 13: abfd->tdata.cisco_core_data->sig = SIGBUS;  break;
 206
 207           /* interrupt           */
 208         case 31: abfd->tdata.cisco_core_data->sig = SIGINT;  break;
 209           /* breakpoint          */
 210         case 33: abfd->tdata.cisco_core_data->sig = SIGTRAP;  break;
 211
 212           /* floating point err  */
 213         case 48: abfd->tdata.cisco_core_data->sig = SIGFPE;  break;
 214           /* floating point err  */
 215         case 49: abfd->tdata.cisco_core_data->sig = SIGFPE;  break;
 216           /* zero divide         */
 217         case 50: abfd->tdata.cisco_core_data->sig = SIGFPE;  break;
 218           /* underflow           */
 219         case 51: abfd->tdata.cisco_core_data->sig = SIGFPE;  break;
 220           /* operand error       */
 221         case 52: abfd->tdata.cisco_core_data->sig = SIGFPE;  break;
 222            /* overflow            */
 223         case 53: abfd->tdata.cisco_core_data->sig = SIGFPE;  break;
 224           /* NAN                 */
 225         case 54: abfd->tdata.cisco_core_data->sig = SIGFPE;  break;
 226         default:
 227 #ifndef SIGEMT
 228 #define SIGEMT SIGTRAP
 229 #endif
 230           /* "software generated"*/
 231           abfd->tdata.cisco_core_data->sig = SIGEMT;
 232         }
 233       break;
 234     default:
 235       /* Unknown crash reason.  */
 236       abfd->tdata.cisco_core_data->sig = 0;
 237       break;
 238     }
 239
 240   abfd->sections = NULL;
 241   abfd->section_count = 0;
 242
 243   /* Create a ".reg" section to allow access to the saved
 244      registers.  */
 245
 246   asect = (asection *) bfd_zmalloc ((bfd_size_type) sizeof (asection));
 247   if (asect == NULL)
 248     goto error_return;
 249   asect->name = ".reg";
 250   asect->flags = SEC_HAS_CONTENTS;
 251   asect->vma = 0;
 252   asect->filepos = bfd_get_32 (abfd, crashinfo.registers) - rambase;
 253   /* Since we don't know the exact size of the saved register info,
 254      choose a register section size that is either the remaining part
 255      of the file, or 1024, whichever is smaller.  */
 256   nread = statbuf.st_size - asect->filepos;
 257   asect->_raw_size = (nread < 1024) ? nread : 1024;
 258   asect->next = abfd->sections;
 259   abfd->sections = asect;
 260   ++abfd->section_count;
 261
 262   /* Create a ".crash" section to allow access to the saved
 263      crash information.  */
 264
 265   asect = (asection *) bfd_zmalloc ((bfd_size_type) sizeof (asection));
 266   if (asect == NULL)
 267     goto error_return;
 268   asect->name = ".crash";
 269   asect->flags = SEC_HAS_CONTENTS;
 270   asect->vma = 0;
 271   asect->filepos = crashinfo_offset;
 272   asect->_raw_size = sizeof (crashinfo);
 273   asect->next = abfd->sections;
 274   abfd->sections = asect;
 275   ++abfd->section_count;
 276
 277   /* Create a ".data" section that maps the entire file, which is
 278      essentially a dump of the target system's RAM.  */
 279
 280   asect = (asection *) bfd_zmalloc ((bfd_size_type) sizeof (asection));
 281   if (asect == NULL)
 282     goto error_return;
 283   asect->name = ".data";
 284   asect->flags = SEC_ALLOC | SEC_LOAD | SEC_HAS_CONTENTS;
 285   /* The size of memory is the size of the core file itself.  */
 286   asect->_raw_size = statbuf.st_size;
 287   asect->vma = rambase;
 288   asect->filepos = 0;
 289   asect->next = abfd->sections;
 290   abfd->sections = asect;
 291   ++abfd->section_count;
 292
 293   return abfd->xvec;
 294
 295   /* Get here if we have already started filling out the BFD
 296      and there is an error of some kind.  */
 297
 298  error_return:
 299   {
 300     sec_ptr nextsect;
 301     for (asect = abfd->sections; asect != NULL;)
 302       {
 303         nextsect = asect->next;
 304         free (asect);
 305         asect = nextsect;
 306       }
 307     free (abfd->tdata.cisco_core_data);
 308     return NULL;
 309   }
 310 }
 311
 312 static const bfd_target *
 313 cisco_core_file_p (abfd)
 314      bfd *abfd;
 315 {
 316   int *crash_info_locp;
 317   const bfd_target *target = NULL;
 318
 319   for (crash_info_locp = crash_info_locs;
 320        *crash_info_locp != -1  &&  target == NULL;
 321        crash_info_locp++)
 322     {
 323       target = cisco_core_file_validate (abfd, *crash_info_locp);
 324     }
 325   return (target);
 326 }
 327
 328 char *
 329 cisco_core_file_failing_command (abfd)
 330      bfd *abfd ATTRIBUTE_UNUSED;
 331 {
 332   return NULL;
 333 }
 334
 335 int
 336 cisco_core_file_failing_signal (abfd)
 337      bfd *abfd ATTRIBUTE_UNUSED;
 338 {
 339   return abfd->tdata.cisco_core_data->sig;
 340 }
 341
 342 boolean
 343 cisco_core_file_matches_executable_p (core_bfd, exec_bfd)
 344      bfd *core_bfd ATTRIBUTE_UNUSED;
 345      bfd *exec_bfd ATTRIBUTE_UNUSED;
 346 {
 347   return true;
 348 }
 349 \f
 350 extern const bfd_target cisco_core_little_vec;
 351
 352 const bfd_target cisco_core_big_vec =
 353   {
 354     "cisco-ios-core-big",
 355     bfd_target_unknown_flavour,
 356     BFD_ENDIAN_BIG,             /* target byte order */
 357     BFD_ENDIAN_BIG,             /* target headers byte order */
 358     (HAS_RELOC | EXEC_P |       /* object flags */
 359      HAS_LINENO | HAS_DEBUG |
 360      HAS_SYMS | HAS_LOCALS | WP_TEXT | D_PAGED),
 361     (SEC_HAS_CONTENTS | SEC_ALLOC | SEC_LOAD | SEC_RELOC), /* section flags */
 362     0,                                                     /* symbol prefix */
 363     ' ',                                                   /* ar_pad_char */
 364     16,                                                    /* ar_max_namelen */
 365     bfd_getb64, bfd_getb_signed_64, bfd_putb64,
 366     bfd_getb32, bfd_getb_signed_32, bfd_putb32,
 367     bfd_getb16, bfd_getb_signed_16, bfd_putb16, /* data */
 368     bfd_getb64, bfd_getb_signed_64, bfd_putb64,
 369     bfd_getb32, bfd_getb_signed_32, bfd_putb32,
 370     bfd_getb16, bfd_getb_signed_16, bfd_putb16, /* hdrs */
 371
 372     {                           /* bfd_check_format */
 373      _bfd_dummy_target,         /* unknown format */
 374      _bfd_dummy_target,         /* object file */
 375      _bfd_dummy_target,         /* archive */
 376      cisco_core_file_p  /* a core file */
 377     },
 378     {                           /* bfd_set_format */
 379      bfd_false, bfd_false,
 380      bfd_false, bfd_false
 381     },
 382     {                           /* bfd_write_contents */
 383      bfd_false, bfd_false,
 384      bfd_false, bfd_false
 385     },
 386
 387        BFD_JUMP_TABLE_GENERIC (_bfd_generic),
 388        BFD_JUMP_TABLE_COPY (_bfd_generic),
 389        BFD_JUMP_TABLE_CORE (cisco),
 390        BFD_JUMP_TABLE_ARCHIVE (_bfd_noarchive),
 391        BFD_JUMP_TABLE_SYMBOLS (_bfd_nosymbols),
 392        BFD_JUMP_TABLE_RELOCS (_bfd_norelocs),
 393        BFD_JUMP_TABLE_WRITE (_bfd_generic),
 394        BFD_JUMP_TABLE_LINK (_bfd_nolink),
 395        BFD_JUMP_TABLE_DYNAMIC (_bfd_nodynamic),
 396
 397     & cisco_core_little_vec,
 398
 399     (PTR) 0                     /* backend_data */
 400 };
 401
 402 const bfd_target cisco_core_little_vec =
 403   {
 404     "cisco-ios-core-little",
 405     bfd_target_unknown_flavour,
 406     BFD_ENDIAN_LITTLE,          /* target byte order */
 407     BFD_ENDIAN_LITTLE,          /* target headers byte order */
 408     (HAS_RELOC | EXEC_P |       /* object flags */
 409      HAS_LINENO | HAS_DEBUG |
 410      HAS_SYMS | HAS_LOCALS | WP_TEXT | D_PAGED),
 411     (SEC_HAS_CONTENTS | SEC_ALLOC | SEC_LOAD | SEC_RELOC), /* section flags */
 412     0,                                                     /* symbol prefix */
 413     ' ',                                                   /* ar_pad_char */
 414     16,                                                    /* ar_max_namelen */
 415     bfd_getl64, bfd_getl_signed_64, bfd_putl64,
 416     bfd_getl32, bfd_getl_signed_32, bfd_putl32,
 417     bfd_getl16, bfd_getl_signed_16, bfd_putl16, /* data */
 418     bfd_getl64, bfd_getl_signed_64, bfd_putl64,
 419     bfd_getl32, bfd_getl_signed_32, bfd_putl32,
 420     bfd_getl16, bfd_getl_signed_16, bfd_putl16, /* hdrs */
 421
 422     {                           /* bfd_check_format */
 423      _bfd_dummy_target,         /* unknown format */
 424      _bfd_dummy_target,         /* object file */
 425      _bfd_dummy_target,         /* archive */
 426      cisco_core_file_p  /* a core file */
 427     },
 428     {                           /* bfd_set_format */
 429      bfd_false, bfd_false,
 430      bfd_false, bfd_false
 431     },
 432     {                           /* bfd_write_contents */
 433      bfd_false, bfd_false,
 434      bfd_false, bfd_false
 435     },
 436
 437        BFD_JUMP_TABLE_GENERIC (_bfd_generic),
 438        BFD_JUMP_TABLE_COPY (_bfd_generic),
 439        BFD_JUMP_TABLE_CORE (cisco),
 440        BFD_JUMP_TABLE_ARCHIVE (_bfd_noarchive),
 441        BFD_JUMP_TABLE_SYMBOLS (_bfd_nosymbols),
 442        BFD_JUMP_TABLE_RELOCS (_bfd_norelocs),
 443        BFD_JUMP_TABLE_WRITE (_bfd_generic),
 444        BFD_JUMP_TABLE_LINK (_bfd_nolink),
 445        BFD_JUMP_TABLE_DYNAMIC (_bfd_nodynamic),
 446
 447     &cisco_core_big_vec,
 448
 449     (PTR) 0                     /* backend_data */
 450 };