/* BFD back-end for CISCO crash dumps. Copyright (C) 1994-2024 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 /* 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 bfd_cleanup 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; size_t amt; flagword flags; if (bfd_seek (abfd, crash_info_loc, SEEK_SET) != 0) return NULL; nread = bfd_read (buf, 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, 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_read (&crashinfo, 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 = bfd_zalloc (abfd, 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 _bfd_no_cleanup; /* 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 bfd_cleanup cisco_core_file_p (bfd *abfd) { int *crash_info_locp; bfd_cleanup cleanup = NULL; for (crash_info_locp = crash_info_locs; *crash_info_locp != -1 && cleanup == NULL; crash_info_locp++) { cleanup = cisco_core_file_validate (abfd, *crash_info_locp); } return cleanup; } 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. */ TARGET_KEEP_UNUSED_SECTION_SYMBOLS, /* keep unused section symbols. */ 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 */ TARGET_KEEP_UNUSED_SECTION_SYMBOLS, /* keep unused section symbols. */ 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 */ };