bfd/trad-core.c

   1 /* BFD back end for traditional Unix core files (U-area and raw sections)
   2    Copyright 1988, 1989, 1991, 1992, 1993, 1994, 1995, 1996, 1998, 1999,
   3    2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2011, 2012
   4    Free Software Foundation, Inc.
   5    Written by John Gilmore of Cygnus Support.
   6
   7    This file is part of BFD, the Binary File Descriptor library.
   8
   9    This program is free software; you can redistribute it and/or modify
  10    it under the terms of the GNU General Public License as published by
  11    the Free Software Foundation; either version 3 of the License, or
  12    (at your option) any later version.
  13
  14    This program is distributed in the hope that it will be useful,
  15    but WITHOUT ANY WARRANTY; without even the implied warranty of
  16    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17    GNU General Public License for more details.
  18
  19    You should have received a copy of the GNU General Public License
  20    along with this program; if not, write to the Free Software
  21    Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
  22    MA 02110-1301, USA.  */
  23
  24 #include "sysdep.h"
  25 #include "bfd.h"
  26 #include "libbfd.h"
  27 #include "libaout.h"           /* BFD a.out internal data structures */
  28
  29 #include <sys/param.h>
  30 #ifdef HAVE_DIRENT_H
  31 # include <dirent.h>
  32 #else
  33 # ifdef HAVE_SYS_NDIR_H
  34 #  include <sys/ndir.h>
  35 # endif
  36 # ifdef HAVE_SYS_DIR_H
  37 #  include <sys/dir.h>
  38 # endif
  39 # ifdef HAVE_NDIR_H
  40 #  include <ndir.h>
  41 # endif
  42 #endif
  43 #include <signal.h>
  44
  45 #include <sys/user.h>           /* After a.out.h  */
  46
  47 #ifdef TRAD_HEADER
  48 #include TRAD_HEADER
  49 #endif
  50
  51 #ifndef NBPG
  52 # define NBPG getpagesize()
  53 #endif
  54
  55 struct trad_core_struct
  56 {
  57   asection *data_section;
  58   asection *stack_section;
  59   asection *reg_section;
  60   struct user u;
  61 };
  62
  63 #define core_upage(bfd)  (&((bfd)->tdata.trad_core_data->u))
  64 #define core_datasec(bfd)  ((bfd)->tdata.trad_core_data->data_section)
  65 #define core_stacksec(bfd) ((bfd)->tdata.trad_core_data->stack_section)
  66 #define core_regsec(bfd)   ((bfd)->tdata.trad_core_data->reg_section)
  67
  68 /* forward declarations */
  69
  70 #define trad_unix_core_file_matches_executable_p generic_core_file_matches_executable_p
  71 #define trad_unix_core_file_pid _bfd_nocore_core_file_pid
  72
  73
  74 /* Handle 4.2-style (and perhaps also sysV-style) core dump file.  */
  75
  76 static const bfd_target *
  77 trad_unix_core_file_p (bfd *abfd)
  78 {
  79   int val;
  80   struct user u;
  81   struct trad_core_struct *rawptr;
  82   bfd_size_type amt;
  83   flagword flags;
  84
  85 #ifdef TRAD_CORE_USER_OFFSET
  86   /* If defined, this macro is the file position of the user struct.  */
  87   if (bfd_seek (abfd, (file_ptr) TRAD_CORE_USER_OFFSET, SEEK_SET) != 0)
  88     return 0;
  89 #endif
  90
  91   val = bfd_bread ((void *) &u, (bfd_size_type) sizeof u, abfd);
  92   if (val != sizeof u)
  93     {
  94       /* Too small to be a core file */
  95       bfd_set_error (bfd_error_wrong_format);
  96       return 0;
  97     }
  98
  99   /* Sanity check perhaps??? */
 100   if (u.u_dsize > 0x1000000)    /* Remember, it's in pages...  */
 101     {
 102       bfd_set_error (bfd_error_wrong_format);
 103       return 0;
 104     }
 105   if (u.u_ssize > 0x1000000)
 106     {
 107       bfd_set_error (bfd_error_wrong_format);
 108       return 0;
 109     }
 110
 111   /* Check that the size claimed is no greater than the file size.  */
 112   {
 113     struct stat statbuf;
 114
 115     if (bfd_stat (abfd, &statbuf) < 0)
 116       return 0;
 117
 118     if ((ufile_ptr) NBPG * (UPAGES + u.u_dsize
 119 #ifdef TRAD_CORE_DSIZE_INCLUDES_TSIZE
 120                             - u.u_tsize
 121 #endif
 122                             + u.u_ssize)
 123         > (ufile_ptr) statbuf.st_size)
 124       {
 125         bfd_set_error (bfd_error_wrong_format);
 126         return 0;
 127       }
 128 #ifndef TRAD_CORE_ALLOW_ANY_EXTRA_SIZE
 129     if (((ufile_ptr) NBPG * (UPAGES + u.u_dsize + u.u_ssize)
 130 #ifdef TRAD_CORE_EXTRA_SIZE_ALLOWED
 131         /* Some systems write the file too big.  */
 132          + TRAD_CORE_EXTRA_SIZE_ALLOWED
 133 #endif
 134          )
 135         < (ufile_ptr) statbuf.st_size)
 136       {
 137         /* The file is too big.  Maybe it's not a core file
 138            or we otherwise have bad values for u_dsize and u_ssize).  */
 139         bfd_set_error (bfd_error_wrong_format);
 140         return 0;
 141       }
 142 #endif
 143   }
 144
 145   /* OK, we believe you.  You're a core file (sure, sure).  */
 146
 147   /* Allocate both the upage and the struct core_data at once, so
 148      a single free() will free them both.  */
 149   amt = sizeof (struct trad_core_struct);
 150   rawptr = (struct trad_core_struct *) bfd_zmalloc (amt);
 151   if (rawptr == NULL)
 152     return 0;
 153
 154   abfd->tdata.trad_core_data = rawptr;
 155
 156   rawptr->u = u; /*Copy the uarea into the tdata part of the bfd */
 157
 158   /* Create the sections.  */
 159
 160   flags = SEC_ALLOC + SEC_LOAD + SEC_HAS_CONTENTS;
 161   core_stacksec(abfd) = bfd_make_section_anyway_with_flags (abfd, ".stack",
 162                                                             flags);
 163   if (core_stacksec (abfd) == NULL)
 164     goto fail;
 165   core_datasec (abfd) = bfd_make_section_anyway_with_flags (abfd, ".data",
 166                                                             flags);
 167   if (core_datasec (abfd) == NULL)
 168     goto fail;
 169   core_regsec (abfd) = bfd_make_section_anyway_with_flags (abfd, ".reg",
 170                                                            SEC_HAS_CONTENTS);
 171   if (core_regsec (abfd) == NULL)
 172     goto fail;
 173
 174   core_datasec (abfd)->size =  NBPG * u.u_dsize
 175 #ifdef TRAD_CORE_DSIZE_INCLUDES_TSIZE
 176     - NBPG * u.u_tsize
 177 #endif
 178       ;
 179   core_stacksec (abfd)->size = NBPG * u.u_ssize;
 180   core_regsec (abfd)->size = NBPG * UPAGES; /* Larger than sizeof struct u */
 181
 182   /* What a hack... we'd like to steal it from the exec file,
 183      since the upage does not seem to provide it.  FIXME.  */
 184 #ifdef HOST_DATA_START_ADDR
 185   core_datasec (abfd)->vma = HOST_DATA_START_ADDR;
 186 #else
 187   core_datasec (abfd)->vma = HOST_TEXT_START_ADDR + (NBPG * u.u_tsize);
 188 #endif
 189
 190 #ifdef HOST_STACK_START_ADDR
 191   core_stacksec (abfd)->vma = HOST_STACK_START_ADDR;
 192 #else
 193   core_stacksec (abfd)->vma = HOST_STACK_END_ADDR - (NBPG * u.u_ssize);
 194 #endif
 195
 196   /* This is tricky.  As the "register section", we give them the entire
 197      upage and stack.  u.u_ar0 points to where "register 0" is stored.
 198      There are two tricks with this, though.  One is that the rest of the
 199      registers might be at positive or negative (or both) displacements
 200      from *u_ar0.  The other is that u_ar0 is sometimes an absolute address
 201      in kernel memory, and on other systems it is an offset from the beginning
 202      of the `struct user'.
 203
 204      As a practical matter, we don't know where the registers actually are,
 205      so we have to pass the whole area to GDB.  We encode the value of u_ar0
 206      by setting the .regs section up so that its virtual memory address
 207      0 is at the place pointed to by u_ar0 (by setting the vma of the start
 208      of the section to -u_ar0).  GDB uses this info to locate the regs,
 209      using minor trickery to get around the offset-or-absolute-addr problem.  */
 210   core_regsec (abfd)->vma = - (bfd_vma) (unsigned long) u.u_ar0;
 211
 212   core_datasec (abfd)->filepos = NBPG * UPAGES;
 213   core_stacksec (abfd)->filepos = (NBPG * UPAGES) + NBPG * u.u_dsize
 214 #ifdef TRAD_CORE_DSIZE_INCLUDES_TSIZE
 215     - NBPG * u.u_tsize
 216 #endif
 217       ;
 218   core_regsec (abfd)->filepos = 0; /* Register segment is the upage */
 219
 220   /* Align to word at least */
 221   core_stacksec (abfd)->alignment_power = 2;
 222   core_datasec (abfd)->alignment_power = 2;
 223   core_regsec (abfd)->alignment_power = 2;
 224
 225   return abfd->xvec;
 226
 227  fail:
 228   bfd_release (abfd, abfd->tdata.any);
 229   abfd->tdata.any = NULL;
 230   bfd_section_list_clear (abfd);
 231   return NULL;
 232 }
 233
 234 static char *
 235 trad_unix_core_file_failing_command (bfd *abfd)
 236 {
 237 #ifndef NO_CORE_COMMAND
 238   char *com = abfd->tdata.trad_core_data->u.u_comm;
 239   if (*com)
 240     return com;
 241   else
 242 #endif
 243     return 0;
 244 }
 245
 246 static int
 247 trad_unix_core_file_failing_signal (bfd *ignore_abfd ATTRIBUTE_UNUSED)
 248 {
 249 #ifdef TRAD_UNIX_CORE_FILE_FAILING_SIGNAL
 250   return TRAD_UNIX_CORE_FILE_FAILING_SIGNAL(ignore_abfd);
 251 #else
 252   return -1;            /* FIXME, where is it? */
 253 #endif
 254 }
 255 \f
 256 /* If somebody calls any byte-swapping routines, shoot them.  */
 257 static void
 258 swap_abort (void)
 259 {
 260   abort (); /* This way doesn't require any declaration for ANSI to fuck up */
 261 }
 262
 263 #define NO_GET ((bfd_vma (*) (const void *)) swap_abort)
 264 #define NO_PUT ((void (*) (bfd_vma, void *)) swap_abort)
 265 #define NO_GETS ((bfd_signed_vma (*) (const void *)) swap_abort)
 266 #define NO_GET64 ((bfd_uint64_t (*) (const void *)) swap_abort)
 267 #define NO_PUT64 ((void (*) (bfd_uint64_t, void *)) swap_abort)
 268 #define NO_GETS64 ((bfd_int64_t (*) (const void *)) swap_abort)
 269
 270 const bfd_target trad_core_vec =
 271   {
 272     "trad-core",
 273     bfd_target_unknown_flavour,
 274     BFD_ENDIAN_UNKNOWN,         /* target byte order */
 275     BFD_ENDIAN_UNKNOWN,         /* target headers byte order */
 276     (HAS_RELOC | EXEC_P |       /* object flags */
 277      HAS_LINENO | HAS_DEBUG |
 278      HAS_SYMS | HAS_LOCALS | WP_TEXT | D_PAGED),
 279     (SEC_HAS_CONTENTS | SEC_ALLOC | SEC_LOAD | SEC_RELOC), /* section flags */
 280     0,                          /* symbol prefix */
 281     ' ',                        /* ar_pad_char */
 282     16,                         /* ar_max_namelen */
 283     0,                          /* match priority.  */
 284     NO_GET64, NO_GETS64, NO_PUT64,      /* 64 bit data */
 285     NO_GET, NO_GETS, NO_PUT,            /* 32 bit data */
 286     NO_GET, NO_GETS, NO_PUT,            /* 16 bit data */
 287     NO_GET64, NO_GETS64, NO_PUT64,      /* 64 bit hdrs */
 288     NO_GET, NO_GETS, NO_PUT,            /* 32 bit hdrs */
 289     NO_GET, NO_GETS, NO_PUT,            /* 16 bit hdrs */
 290
 291     {                           /* bfd_check_format */
 292       _bfd_dummy_target,                /* unknown format */
 293       _bfd_dummy_target,                /* object file */
 294       _bfd_dummy_target,                /* archive */
 295       trad_unix_core_file_p             /* a core file */
 296     },
 297     {                           /* bfd_set_format */
 298       bfd_false, bfd_false,
 299       bfd_false, bfd_false
 300     },
 301     {                           /* bfd_write_contents */
 302       bfd_false, bfd_false,
 303       bfd_false, bfd_false
 304     },
 305
 306     BFD_JUMP_TABLE_GENERIC (_bfd_generic),
 307     BFD_JUMP_TABLE_COPY (_bfd_generic),
 308     BFD_JUMP_TABLE_CORE (trad_unix),
 309     BFD_JUMP_TABLE_ARCHIVE (_bfd_noarchive),
 310     BFD_JUMP_TABLE_SYMBOLS (_bfd_nosymbols),
 311     BFD_JUMP_TABLE_RELOCS (_bfd_norelocs),
 312     BFD_JUMP_TABLE_WRITE (_bfd_generic),
 313     BFD_JUMP_TABLE_LINK (_bfd_nolink),
 314     BFD_JUMP_TABLE_DYNAMIC (_bfd_nodynamic),
 315
 316     NULL,
 317
 318     NULL                        /* backend_data */
 319   };