/* BFD back-end for CISCO crash dumps.
Copyright (C) 1994-2018 Free Software Foundation, Inc.
This file is part of BFD, the Binary File Descriptor library.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
MA 02110-1301, USA. */
#include "sysdep.h"
#include "bfd.h"
#include "libbfd.h"
/* core_file_failing_signal returns a host signal (this probably should
be fixed). */
#include <signal.h>
/* for MSVC builds */
#ifndef SIGTRAP
# define SIGTRAP 5
#endif
#ifndef SIGEMT
# define SIGEMT 6
#endif
#ifndef SIGBUS
# define SIGBUS 10
#endif
int crash_info_locs[] =
{
0x0250, /* mips, ppc, x86, i960 */
0x0400, /* m68k, mips, x86, i960 */
0x0FFC, /* m68k, mips, ppc, x86, i960 */
0x3000, /* ppc */
0x4FFC, /* m68k */
-1
};
#define CRASH_MAGIC 0xdead1234
#define MASK_ADDR(x) ((x) & 0x0fffffff) /* Mask crash info address */
typedef enum
{
CRASH_REASON_NOTCRASHED = 0,
CRASH_REASON_EXCEPTION = 1,
CRASH_REASON_CORRUPT = 2,
} crashreason;
typedef struct
{
char magic[4]; /* Magic number */
char version[4]; /* Version number */
char reason[4]; /* Crash reason */
char cpu_vector[4]; /* CPU vector for exceptions */
char registers[4]; /* Pointer to saved registers */
char rambase[4]; /* Base of RAM (not in V1 crash info) */
char textbase[4]; /* Base of .text section (not in V3 crash info) */
char database[4]; /* Base of .data section (not in V3 crash info) */
char bssbase[4]; /* Base of .bss section (not in V3 crash info) */
} crashinfo_external;
struct cisco_core_struct
{
int sig;
};
#define cisco_core_file_matches_executable_p generic_core_file_matches_executable_p
#define cisco_core_file_pid _bfd_nocore_core_file_pid
/* Examine the file for a crash info struct at the offset given by
CRASH_INFO_LOC. */
static const bfd_target *
cisco_core_file_validate (bfd *abfd, int crash_info_loc)
{
char buf[4];
unsigned int crashinfo_offset;
crashinfo_external crashinfo;
bfd_size_type nread;
unsigned int magic;
unsigned int version;
unsigned int rambase;
sec_ptr asect;
struct stat statbuf;
bfd_size_type amt;
flagword flags;
if (bfd_seek (abfd, (file_ptr) crash_info_loc, SEEK_SET) != 0)
return NULL;
nread = bfd_bread (buf, (bfd_size_type) 4, abfd);
if (nread != 4)
{
if (bfd_get_error () != bfd_error_system_call)
bfd_set_error (bfd_error_wrong_format);
return NULL;
}
crashinfo_offset = MASK_ADDR (bfd_get_32 (abfd, buf));
if (bfd_seek (abfd, (file_ptr) crashinfo_offset, SEEK_SET) != 0)
{
/* Most likely we failed because of a bogus (huge) offset */
bfd_set_error (bfd_error_wrong_format);
return NULL;
}
nread = bfd_bread (&crashinfo, (bfd_size_type) sizeof (crashinfo), abfd);
if (nread != sizeof (crashinfo))
{
if (bfd_get_error () != bfd_error_system_call)
bfd_set_error (bfd_error_wrong_format);
return NULL;
}
if (bfd_stat (abfd, &statbuf) < 0)
{
bfd_set_error (bfd_error_system_call);
return NULL;
}
magic = bfd_get_32 (abfd, crashinfo.magic);
if (magic != CRASH_MAGIC)
{
bfd_set_error (bfd_error_wrong_format);
return NULL;
}
version = bfd_get_32 (abfd, crashinfo.version);
if (version == 0)
{
bfd_set_error (bfd_error_wrong_format);
return NULL;
}
else if (version == 1)
{
/* V1 core dumps don't specify the dump base, assume 0 */
rambase = 0;
}
else
{
rambase = bfd_get_32 (abfd, crashinfo.rambase);
}
/* OK, we believe you. You're a core file. */
amt = sizeof (struct cisco_core_struct);
abfd->tdata.cisco_core_data = (struct cisco_core_struct *) bfd_zmalloc (amt);
if (abfd->tdata.cisco_core_data == NULL)
return NULL;
switch ((crashreason) bfd_get_32 (abfd, crashinfo.reason))
{
case CRASH_REASON_NOTCRASHED:
/* Crash file probably came from write core. */
abfd->tdata.cisco_core_data->sig = 0;
break;
case CRASH_REASON_CORRUPT:
/* The crash context area was corrupt -- proceed with caution.
We have no way of passing this information back to the caller. */
abfd->tdata.cisco_core_data->sig = 0;
break;
case CRASH_REASON_EXCEPTION:
/* Crash occured due to CPU exception. */
/* This is 68k-specific; for MIPS we'll need to interpret
cpu_vector differently based on the target configuration
(since CISCO core files don't seem to have the processor
encoded in them). */
switch (bfd_get_32 (abfd, crashinfo.cpu_vector))
{
/* bus error */
case 2 : abfd->tdata.cisco_core_data->sig = SIGBUS; break;
/* address error */
case 3 : abfd->tdata.cisco_core_data->sig = SIGBUS; break;
/* illegal instruction */
case 4 : abfd->tdata.cisco_core_data->sig = SIGILL; break;
/* zero divide */
case 5 : abfd->tdata.cisco_core_data->sig = SIGFPE; break;
/* chk instruction */
case 6 : abfd->tdata.cisco_core_data->sig = SIGFPE; break;
/* trapv instruction */
case 7 : abfd->tdata.cisco_core_data->sig = SIGFPE; break;
/* privilege violation */
case 8 : abfd->tdata.cisco_core_data->sig = SIGSEGV; break;
/* trace trap */
case 9 : abfd->tdata.cisco_core_data->sig = SIGTRAP; break;
/* line 1010 emulator */
case 10: abfd->tdata.cisco_core_data->sig = SIGILL; break;
/* line 1111 emulator */
case 11: abfd->tdata.cisco_core_data->sig = SIGILL; break;
/* Coprocessor protocol violation. Using a standard MMU or FPU
this cannot be triggered by software. Call it a SIGBUS. */
case 13: abfd->tdata.cisco_core_data->sig = SIGBUS; break;
/* interrupt */
case 31: abfd->tdata.cisco_core_data->sig = SIGINT; break;
/* breakpoint */
case 33: abfd->tdata.cisco_core_data->sig = SIGTRAP; break;
/* floating point err */
case 48: abfd->tdata.cisco_core_data->sig = SIGFPE; break;
/* floating point err */
case 49: abfd->tdata.cisco_core_data->sig = SIGFPE; break;
/* zero divide */
case 50: abfd->tdata.cisco_core_data->sig = SIGFPE; break;
/* underflow */
case 51: abfd->tdata.cisco_core_data->sig = SIGFPE; break;
/* operand error */
case 52: abfd->tdata.cisco_core_data->sig = SIGFPE; break;
/* overflow */
case 53: abfd->tdata.cisco_core_data->sig = SIGFPE; break;
/* NAN */
case 54: abfd->tdata.cisco_core_data->sig = SIGFPE; break;
default:
#ifndef SIGEMT
#define SIGEMT SIGTRAP
#endif
/* "software generated"*/
abfd->tdata.cisco_core_data->sig = SIGEMT;
}
break;
default:
/* Unknown crash reason. */
abfd->tdata.cisco_core_data->sig = 0;
break;
}
/* Create a ".data" section that maps the entire file, which is
essentially a dump of the target system's RAM. */
flags = SEC_ALLOC | SEC_LOAD | SEC_HAS_CONTENTS;
asect = bfd_make_section_anyway_with_flags (abfd, ".data", flags);
if (asect == NULL)
goto error_return;
/* The size of memory is the size of the core file itself. */
asect->size = statbuf.st_size;
asect->vma = rambase;
asect->filepos = 0;
/* Create a ".crash" section to allow access to the saved
crash information. */
flags = SEC_HAS_CONTENTS;
asect = bfd_make_section_anyway_with_flags (abfd, ".crash", flags);
if (asect == NULL)
goto error_return;
asect->vma = 0;
asect->filepos = crashinfo_offset;
asect->size = sizeof (crashinfo);
/* Create a ".reg" section to allow access to the saved
registers. */
asect = bfd_make_section_anyway_with_flags (abfd, ".reg", flags);
if (asect == NULL)
goto error_return;
asect->vma = 0;
asect->filepos = bfd_get_32 (abfd, crashinfo.registers) - rambase;
/* Since we don't know the exact size of the saved register info,
choose a register section size that is either the remaining part
of the file, or 1024, whichever is smaller. */
nread = statbuf.st_size - asect->filepos;
asect->size = (nread < 1024) ? nread : 1024;
return abfd->xvec;
/* Get here if we have already started filling out the BFD
and there is an error of some kind. */
error_return:
bfd_release (abfd, abfd->tdata.any);
abfd->tdata.any = NULL;
bfd_section_list_clear (abfd);
return NULL;
}
static const bfd_target *
cisco_core_file_p (bfd *abfd)
{
int *crash_info_locp;
const bfd_target *target = NULL;
for (crash_info_locp = crash_info_locs;
*crash_info_locp != -1 && target == NULL;
crash_info_locp++)
{
target = cisco_core_file_validate (abfd, *crash_info_locp);
}
return (target);
}
static char *
cisco_core_file_failing_command (bfd *abfd ATTRIBUTE_UNUSED)
{
return NULL;
}
static int
cisco_core_file_failing_signal (bfd *abfd ATTRIBUTE_UNUSED)
{
return abfd->tdata.cisco_core_data->sig;
}
extern const bfd_target core_cisco_le_vec;
const bfd_target core_cisco_be_vec =
{
"cisco-ios-core-big",
bfd_target_unknown_flavour,
BFD_ENDIAN_BIG, /* target byte order */
BFD_ENDIAN_BIG, /* target headers byte order */
(HAS_RELOC | EXEC_P /* object flags */
| HAS_LINENO | HAS_DEBUG
| HAS_SYMS | HAS_LOCALS | WP_TEXT | D_PAGED),
(SEC_HAS_CONTENTS | SEC_ALLOC | SEC_LOAD | SEC_RELOC), /* section flags */
0, /* symbol prefix */
' ', /* ar_pad_char */
16, /* ar_max_namelen */
0, /* match priority. */
bfd_getb64, bfd_getb_signed_64, bfd_putb64,
bfd_getb32, bfd_getb_signed_32, bfd_putb32,
bfd_getb16, bfd_getb_signed_16, bfd_putb16, /* data */
bfd_getb64, bfd_getb_signed_64, bfd_putb64,
bfd_getb32, bfd_getb_signed_32, bfd_putb32,
bfd_getb16, bfd_getb_signed_16, bfd_putb16, /* hdrs */
{ /* bfd_check_format */
_bfd_dummy_target, /* unknown format */
_bfd_dummy_target, /* object file */
_bfd_dummy_target, /* archive */
cisco_core_file_p /* a core file */
},
{ /* bfd_set_format */
_bfd_bool_bfd_false_error,
_bfd_bool_bfd_false_error,
_bfd_bool_bfd_false_error,
_bfd_bool_bfd_false_error
},
{ /* bfd_write_contents */
_bfd_bool_bfd_false_error,
_bfd_bool_bfd_false_error,
_bfd_bool_bfd_false_error,
_bfd_bool_bfd_false_error
},
BFD_JUMP_TABLE_GENERIC (_bfd_generic),
BFD_JUMP_TABLE_COPY (_bfd_generic),
BFD_JUMP_TABLE_CORE (cisco),
BFD_JUMP_TABLE_ARCHIVE (_bfd_noarchive),
BFD_JUMP_TABLE_SYMBOLS (_bfd_nosymbols),
BFD_JUMP_TABLE_RELOCS (_bfd_norelocs),
BFD_JUMP_TABLE_WRITE (_bfd_generic),
BFD_JUMP_TABLE_LINK (_bfd_nolink),
BFD_JUMP_TABLE_DYNAMIC (_bfd_nodynamic),
&core_cisco_le_vec,
NULL /* backend_data */
};
const bfd_target core_cisco_le_vec =
{
"cisco-ios-core-little",
bfd_target_unknown_flavour,
BFD_ENDIAN_LITTLE, /* target byte order */
BFD_ENDIAN_LITTLE, /* target headers byte order */
(HAS_RELOC | EXEC_P /* object flags */
| HAS_LINENO | HAS_DEBUG
| HAS_SYMS | HAS_LOCALS | WP_TEXT | D_PAGED),
(SEC_HAS_CONTENTS | SEC_ALLOC | SEC_LOAD | SEC_RELOC), /* section flags */
0, /* symbol prefix */
' ', /* ar_pad_char */
16, /* ar_max_namelen */
0, /* match_priority */
bfd_getl64, bfd_getl_signed_64, bfd_putl64,
bfd_getl32, bfd_getl_signed_32, bfd_putl32,
bfd_getl16, bfd_getl_signed_16, bfd_putl16, /* data */
bfd_getl64, bfd_getl_signed_64, bfd_putl64,
bfd_getl32, bfd_getl_signed_32, bfd_putl32,
bfd_getl16, bfd_getl_signed_16, bfd_putl16, /* hdrs */
{ /* bfd_check_format */
_bfd_dummy_target, /* unknown format */
_bfd_dummy_target, /* object file */
_bfd_dummy_target, /* archive */
cisco_core_file_p /* a core file */
},
{ /* bfd_set_format */
_bfd_bool_bfd_false_error,
_bfd_bool_bfd_false_error,
_bfd_bool_bfd_false_error,
_bfd_bool_bfd_false_error
},
{ /* bfd_write_contents */
_bfd_bool_bfd_false_error,
_bfd_bool_bfd_false_error,
_bfd_bool_bfd_false_error,
_bfd_bool_bfd_false_error
},
BFD_JUMP_TABLE_GENERIC (_bfd_generic),
BFD_JUMP_TABLE_COPY (_bfd_generic),
BFD_JUMP_TABLE_CORE (cisco),
BFD_JUMP_TABLE_ARCHIVE (_bfd_noarchive),
BFD_JUMP_TABLE_SYMBOLS (_bfd_nosymbols),
BFD_JUMP_TABLE_RELOCS (_bfd_norelocs),
BFD_JUMP_TABLE_WRITE (_bfd_generic),
BFD_JUMP_TABLE_LINK (_bfd_nolink),
BFD_JUMP_TABLE_DYNAMIC (_bfd_nodynamic),
&core_cisco_be_vec,
NULL /* backend_data */
};