From 830db0485e19000985ccfdbacda4d4d5d62583bb Mon Sep 17 00:00:00 2001 From: Zebediah Figura Date: Mon, 12 Feb 2018 13:12:45 +0000 Subject: [PATCH] Add support for reading msdos MZ executables. See email thread starting here: https://www.sourceware.org/ml/binutils/2018-01/msg00001.html include * coff/msdos.h: New header. * coff/pe.h: Move common defines to msdos.h. * coff/powerpc.h: Likewise. bfd * i386msdos.c (msdos_mkobject); New function. (msdos_object_p): New function. (i386_msdos_vec): Use msdos_object_p as the check_format function. * peicode.h: Rename external_PEI_DOS_hdr, DOSMAGIC, and NT_SIGNATURE to external_DOS_hdr, IMAGE_DOS_SIGNATURE, and IMAGE_NT_SIGNATURE. * peXXigen.c: Likewise. * coff-ia64.c: Likewise. --- bfd/ChangeLog | 12 ++++++ bfd/coff-ia64.c | 6 +-- bfd/i386msdos.c | 89 ++++++++++++++++++++++++++++++++++++++++-- bfd/peXXigen.c | 4 +- bfd/peicode.h | 6 +-- include/ChangeLog | 6 +++ include/coff/msdos.h | 57 +++++++++++++++++++++++++++ include/coff/pe.h | 31 +-------------- include/coff/powerpc.h | 2 - 9 files changed, 170 insertions(+), 43 deletions(-) create mode 100644 include/coff/msdos.h diff --git a/bfd/ChangeLog b/bfd/ChangeLog index f1478064a4..960e48492c 100644 --- a/bfd/ChangeLog +++ b/bfd/ChangeLog @@ -1,3 +1,15 @@ +2018-02-12 Zebediah Figura + + * i386msdos.c (msdos_mkobject); New function. + (msdos_object_p): New function. + (i386_msdos_vec): Use msdos_object_p as the check_format + function. + * peicode.h: Rename external_PEI_DOS_hdr, DOSMAGIC, and + NT_SIGNATURE to external_DOS_hdr, IMAGE_DOS_SIGNATURE, and + IMAGE_NT_SIGNATURE. + * peXXigen.c: Likewise. + * coff-ia64.c: Likewise. + 2018-02-12 Nick Clifton * elf32-nds32.c (nds32_elf_relax_longjump3): Remove redundant diff --git a/bfd/coff-ia64.c b/bfd/coff-ia64.c index 56100dd4c7..270c959dff 100644 --- a/bfd/coff-ia64.c +++ b/bfd/coff-ia64.c @@ -72,7 +72,7 @@ ia64coff_object_p (bfd *abfd) { #ifdef COFF_IMAGE_WITH_PE { - struct external_PEI_DOS_hdr dos_hdr; + struct external_DOS_hdr dos_hdr; struct external_PEI_IMAGE_hdr image_hdr; file_ptr offset; @@ -87,7 +87,7 @@ ia64coff_object_p (bfd *abfd) /* There are really two magic numbers involved; the magic number that says this is a NT executable (PEI) and the magic number - that determines the architecture. The former is DOSMAGIC, + that determines the architecture. The former is IMAGE_DOS_SIGNATURE, stored in the e_magic field. The latter is stored in the f_magic field. If the NT magic number isn't valid, the architecture magic number could be mimicked by some other @@ -95,7 +95,7 @@ ia64coff_object_p (bfd *abfd) this routine can only be called correctly for a PEI file, check the e_magic number here, and, if it doesn't match, clobber the f_magic number so that we don't get a false match. */ - if (H_GET_16 (abfd, dos_hdr.e_magic) != DOSMAGIC) + if (H_GET_16 (abfd, dos_hdr.e_magic) != IMAGE_DOS_SIGNATURE) { bfd_set_error (bfd_error_wrong_format); return NULL; diff --git a/bfd/i386msdos.c b/bfd/i386msdos.c index c15707c38d..5437b162fa 100644 --- a/bfd/i386msdos.c +++ b/bfd/i386msdos.c @@ -27,12 +27,94 @@ #include "bfd.h" #include "libbfd.h" #include "libaout.h" +#include "coff/msdos.h" -#define EXE_MAGIC 0x5a4d #define EXE_LOAD_HIGH 0x0000 #define EXE_LOAD_LOW 0xffff #define EXE_PAGE_SIZE 512 +static bfd_boolean +msdos_mkobject (bfd *abfd) +{ + bfd_default_set_arch_mach (abfd, bfd_arch_i386, bfd_mach_i386_i8086); + + return aout_32_mkobject (abfd); +} + +static const bfd_target * +msdos_object_p (bfd *abfd) +{ + struct external_DOS_hdr hdr; + bfd_byte buffer[2]; + asection *section; + unsigned int size; + + if (bfd_seek (abfd, (file_ptr) 0, SEEK_SET) != 0 + || bfd_bread (&hdr, (bfd_size_type) sizeof (hdr), abfd) < DOS_HDR_SIZE) + { + if (bfd_get_error () != bfd_error_system_call) + bfd_set_error (bfd_error_wrong_format); + return NULL; + } + + if (H_GET_16 (abfd, hdr.e_magic) != IMAGE_DOS_SIGNATURE) + { + bfd_set_error (bfd_error_wrong_format); + return NULL; + } + + /* Check that this isn't actually a PE, NE, or LE file. If it is, the + e_lfanew field will be valid and point to a header beginning with one of + the relevant signatures. If not, e_lfanew might point to anything, so + don't bail if we can't read there. */ + if (H_GET_16 (abfd, hdr.e_cparhdr) < 4 + || bfd_seek (abfd, (file_ptr) H_GET_32 (abfd, hdr.e_lfanew), SEEK_SET) != 0 + || bfd_bread (buffer, (bfd_size_type) 2, abfd) != 2) + { + if (bfd_get_error () == bfd_error_system_call) + return NULL; + } + else + { + if (H_GET_16 (abfd, buffer) == IMAGE_NT_SIGNATURE + || H_GET_16 (abfd, buffer) == IMAGE_OS2_SIGNATURE + || H_GET_16 (abfd, buffer) == IMAGE_OS2_SIGNATURE_LE + || H_GET_16 (abfd, buffer) == IMAGE_OS2_SIGNATURE_LX) + { + bfd_set_error (bfd_error_wrong_format); + return NULL; + } + } + + if (!msdos_mkobject (abfd)) + return NULL; + + abfd->flags = EXEC_P; + abfd->start_address = H_GET_16 (abfd, hdr.e_ip); + + section = bfd_make_section (abfd, ".text"); + if (section == NULL) + return NULL; + + section->flags = (SEC_ALLOC | SEC_LOAD | SEC_CODE | SEC_HAS_CONTENTS); + section->filepos = H_GET_16 (abfd, hdr.e_cparhdr) * 16; + size = (H_GET_16 (abfd, hdr.e_cp) - 1) * EXE_PAGE_SIZE - section->filepos; + size += H_GET_16 (abfd, hdr.e_cblp); + + /* Check that the size is valid. */ + if (bfd_seek (abfd, (file_ptr) (section->filepos + size), SEEK_SET) != 0) + { + if (bfd_get_error () != bfd_error_system_call) + bfd_set_error (bfd_error_wrong_format); + return NULL; + } + + bfd_set_section_size (abfd, section, size); + section->alignment_power = 4; + + return abfd->xvec; +} + static int msdos_sizeof_headers (bfd *abfd ATTRIBUTE_UNUSED, struct bfd_link_info *info ATTRIBUTE_UNUSED) @@ -77,7 +159,7 @@ msdos_write_object_contents (bfd *abfd) } /* Constants. */ - H_PUT_16 (abfd, EXE_MAGIC, &hdr[0]); + H_PUT_16 (abfd, IMAGE_DOS_SIGNATURE, &hdr[0]); H_PUT_16 (abfd, EXE_PAGE_SIZE / 16, &hdr[8]); H_PUT_16 (abfd, EXE_LOAD_LOW, &hdr[12]); H_PUT_16 (abfd, 0x3e, &hdr[24]); @@ -127,7 +209,6 @@ msdos_set_section_contents (bfd *abfd, -#define msdos_mkobject aout_32_mkobject #define msdos_make_empty_symbol aout_32_make_empty_symbol #define msdos_bfd_reloc_type_lookup aout_32_reloc_type_lookup #define msdos_bfd_reloc_name_lookup aout_32_reloc_name_lookup @@ -203,7 +284,7 @@ const bfd_target i386_msdos_vec = { _bfd_dummy_target, - _bfd_dummy_target, /* bfd_check_format */ + msdos_object_p, /* bfd_check_format */ _bfd_dummy_target, _bfd_dummy_target, }, diff --git a/bfd/peXXigen.c b/bfd/peXXigen.c index 679dabf4cf..6caca1729b 100644 --- a/bfd/peXXigen.c +++ b/bfd/peXXigen.c @@ -828,7 +828,7 @@ _bfd_XXi_only_swap_filehdr_out (bfd * abfd, void * in, void * out) if (pe_data (abfd)->dll) filehdr_in->f_flags |= F_DLL; - filehdr_in->pe.e_magic = DOSMAGIC; + filehdr_in->pe.e_magic = IMAGE_DOS_SIGNATURE; filehdr_in->pe.e_cblp = 0x90; filehdr_in->pe.e_cp = 0x3; filehdr_in->pe.e_crlc = 0x0; @@ -872,7 +872,7 @@ _bfd_XXi_only_swap_filehdr_out (bfd * abfd, void * in, void * out) filehdr_in->pe.dos_message[13] = 0x0a0d0d2e; filehdr_in->pe.dos_message[14] = 0x24; filehdr_in->pe.dos_message[15] = 0x0; - filehdr_in->pe.nt_signature = NT_SIGNATURE; + filehdr_in->pe.nt_signature = IMAGE_NT_SIGNATURE; H_PUT_16 (abfd, filehdr_in->f_magic, filehdr_out->f_magic); H_PUT_16 (abfd, filehdr_in->f_nscns, filehdr_out->f_nscns); diff --git a/bfd/peicode.h b/bfd/peicode.h index 94dd861a91..30dc08b45e 100644 --- a/bfd/peicode.h +++ b/bfd/peicode.h @@ -1386,7 +1386,7 @@ static const bfd_target * pe_bfd_object_p (bfd * abfd) { bfd_byte buffer[6]; - struct external_PEI_DOS_hdr dos_hdr; + struct external_DOS_hdr dos_hdr; struct external_PEI_IMAGE_hdr image_hdr; struct internal_filehdr internal_f; struct internal_aouthdr internal_a; @@ -1420,7 +1420,7 @@ pe_bfd_object_p (bfd * abfd) /* There are really two magic numbers involved; the magic number that says this is a NT executable (PEI) and the magic number that - determines the architecture. The former is DOSMAGIC, stored in + determines the architecture. The former is IMAGE_DOS_SIGNATURE, stored in the e_magic field. The latter is stored in the f_magic field. If the NT magic number isn't valid, the architecture magic number could be mimicked by some other field (specifically, the number @@ -1428,7 +1428,7 @@ pe_bfd_object_p (bfd * abfd) correctly for a PEI file, check the e_magic number here, and, if it doesn't match, clobber the f_magic number so that we don't get a false match. */ - if (H_GET_16 (abfd, dos_hdr.e_magic) != DOSMAGIC) + if (H_GET_16 (abfd, dos_hdr.e_magic) != IMAGE_DOS_SIGNATURE) { bfd_set_error (bfd_error_wrong_format); return NULL; diff --git a/include/ChangeLog b/include/ChangeLog index ea7476c2f3..2563ab5839 100644 --- a/include/ChangeLog +++ b/include/ChangeLog @@ -1,3 +1,9 @@ +2018-02-12 Zebediah Figura + + * coff/msdos.h: New header. + * coff/pe.h: Move common defines to msdos.h. + * coff/powerpc.h: Likewise. + 2018-01-13 Nick Clifton 2.30 branch created. diff --git a/include/coff/msdos.h b/include/coff/msdos.h new file mode 100644 index 0000000000..cebd957152 --- /dev/null +++ b/include/coff/msdos.h @@ -0,0 +1,57 @@ +/* msdos.h - MS-DOS and derived executable header information + + Copyright (C) 1999-2018 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. */ +#ifndef _MSDOS_H +#define _MSDOS_H + +#define IMAGE_DOS_SIGNATURE 0x5a4d /* MZ */ +#define IMAGE_OS2_SIGNATURE 0x454e /* NE */ +#define IMAGE_OS2_SIGNATURE_LE 0x454c /* LE */ +#define IMAGE_OS2_SIGNATURE_LX 0x584c /* LX */ +#define IMAGE_NT_SIGNATURE 0x00004550 /* PE\0\0 */ + +struct external_DOS_hdr +{ + /* DOS header fields - always at offset zero in the EXE file. */ + char e_magic[2]; /* Magic number. */ + char e_cblp[2]; /* Bytes on last page of file. */ + char e_cp[2]; /* Pages in file. */ + char e_crlc[2]; /* Relocations. */ + char e_cparhdr[2]; /* Size of header in paragraphs. */ + char e_minalloc[2]; /* Minimum extra paragraphs needed. */ + char e_maxalloc[2]; /* Maximum extra paragraphs needed. */ + char e_ss[2]; /* Initial (relative) SS value. */ + char e_sp[2]; /* Initial SP value. */ + char e_csum[2]; /* Checksum. */ + char e_ip[2]; /* Initial IP value. */ + char e_cs[2]; /* Initial (relative) CS value. */ + char e_lfarlc[2]; /* File address of relocation table. */ + char e_ovno[2]; /* Overlay number. */ + char e_res[4][2]; /* Reserved words, all 0x0. */ + char e_oemid[2]; /* OEM identifier. */ + char e_oeminfo[2]; /* OEM information. */ + char e_res2[10][2]; /* Reserved words, all 0x0. */ + char e_lfanew[4]; /* File address of new exe header, usually 0x80. */ + char dos_message[16][4]; /* Other stuff, always follow DOS header. */ +}; + +/* The actual DOS header only includes up to the e_ovno field. */ +#define DOS_HDR_SIZE (offsetof (struct external_DOS_hdr, e_res)) + +#endif /* _MSDOS_H */ diff --git a/include/coff/pe.h b/include/coff/pe.h index f9035bf8a3..56cc4e20c2 100644 --- a/include/coff/pe.h +++ b/include/coff/pe.h @@ -20,6 +20,8 @@ #ifndef _PE_H #define _PE_H +#include "msdos.h" + /* NT specific file attributes. */ #define IMAGE_FILE_RELOCS_STRIPPED 0x0001 #define IMAGE_FILE_EXECUTABLE_IMAGE 0x0002 @@ -168,40 +170,11 @@ #define IMAGE_SUBSYSTEM_SAL_RUNTIME_DRIVER 13 #define IMAGE_SUBSYSTEM_XBOX 14 -/* Magic values that are true for all dos/nt implementations. */ -#define DOSMAGIC 0x5a4d -#define NT_SIGNATURE 0x00004550 - /* NT allows long filenames, we want to accommodate this. This may break some of the bfd functions. */ #undef FILNMLEN #define FILNMLEN 18 /* # characters in a file name. */ -struct external_PEI_DOS_hdr -{ - /* DOS header fields - always at offset zero in the EXE file. */ - char e_magic[2]; /* Magic number, 0x5a4d. */ - char e_cblp[2]; /* Bytes on last page of file, 0x90. */ - char e_cp[2]; /* Pages in file, 0x3. */ - char e_crlc[2]; /* Relocations, 0x0. */ - char e_cparhdr[2]; /* Size of header in paragraphs, 0x4. */ - char e_minalloc[2]; /* Minimum extra paragraphs needed, 0x0. */ - char e_maxalloc[2]; /* Maximum extra paragraphs needed, 0xFFFF. */ - char e_ss[2]; /* Initial (relative) SS value, 0x0. */ - char e_sp[2]; /* Initial SP value, 0xb8. */ - char e_csum[2]; /* Checksum, 0x0. */ - char e_ip[2]; /* Initial IP value, 0x0. */ - char e_cs[2]; /* Initial (relative) CS value, 0x0. */ - char e_lfarlc[2]; /* File address of relocation table, 0x40. */ - char e_ovno[2]; /* Overlay number, 0x0. */ - char e_res[4][2]; /* Reserved words, all 0x0. */ - char e_oemid[2]; /* OEM identifier (for e_oeminfo), 0x0. */ - char e_oeminfo[2]; /* OEM information; e_oemid specific, 0x0. */ - char e_res2[10][2]; /* Reserved words, all 0x0. */ - char e_lfanew[4]; /* File address of new exe header, usually 0x80. */ - char dos_message[16][4]; /* Other stuff, always follow DOS header. */ -}; - struct external_PEI_IMAGE_hdr { char nt_signature[4]; /* Required NT signature, 0x4550. */ diff --git a/include/coff/powerpc.h b/include/coff/powerpc.h index 37fef428ba..a5e56fb1e7 100644 --- a/include/coff/powerpc.h +++ b/include/coff/powerpc.h @@ -37,8 +37,6 @@ /* extra NT defines */ #define PPCMAGIC 0760 /* peeked on aa PowerPC Windows NT box */ -#define DOSMAGIC 0x5a4d /* from arm.h, i386.h */ -#define NT_SIGNATURE 0x00004550 /* from arm.h, i386.h */ /* from winnt.h */ #define IMAGE_NT_OPTIONAL_HDR_MAGIC 0x10b -- 2.34.1