diff options
Diffstat (limited to 'binutils-2.25/bfd/nlm32-i386.c')
| -rw-r--r-- | binutils-2.25/bfd/nlm32-i386.c | 430 |
1 files changed, 430 insertions, 0 deletions
diff --git a/binutils-2.25/bfd/nlm32-i386.c b/binutils-2.25/bfd/nlm32-i386.c new file mode 100644 index 00000000..28b4433f --- /dev/null +++ b/binutils-2.25/bfd/nlm32-i386.c @@ -0,0 +1,430 @@ +/* Support for 32-bit i386 NLM (NetWare Loadable Module) + Copyright 1993, 1994, 2000, 2001, 2002, 2003, 2005, 2007, 2012 + 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" + +#define ARCH_SIZE 32 + +#include "nlm/i386-ext.h" +#define Nlm_External_Fixed_Header Nlm32_i386_External_Fixed_Header + +#include "libnlm.h" + +/* Adjust the reloc location by an absolute value. */ + +static reloc_howto_type nlm_i386_abs_howto = + HOWTO (0, /* Type. */ + 0, /* Rightshift. */ + 2, /* Size (0 = byte, 1 = short, 2 = long). */ + 32, /* Bitsize. */ + FALSE, /* PC relative. */ + 0, /* Bitpos. */ + complain_overflow_bitfield, /* Complain_on_overflow. */ + 0, /* Special_function. */ + "32", /* Name. */ + TRUE, /* Partial_inplace. */ + 0xffffffff, /* Source mask. */ + 0xffffffff, /* Dest mask. */ + FALSE); /* PR rel_offset. */ + +/* Adjust the reloc location by a PC relative displacement. */ + +static reloc_howto_type nlm_i386_pcrel_howto = + HOWTO (1, /* Type. */ + 0, /* Rightshift. */ + 2, /* Size (0 = byte, 1 = short, 2 = long). */ + 32, /* Bitsize. */ + TRUE, /* PC relative. */ + 0, /* Bitpos. */ + complain_overflow_signed, /* Complain_on_overflow. */ + 0, /* Special_function. */ + "DISP32", /* Name. */ + TRUE, /* Partial_inplace. */ + 0xffffffff, /* Source mask. */ + 0xffffffff, /* Dest mask. */ + TRUE); /* PR rel_offset. */ + +/* Read a NetWare i386 reloc. */ + +static bfd_boolean +nlm_i386_read_reloc (bfd *abfd, + nlmNAME (symbol_type) *sym, + asection **secp, + arelent *rel) +{ + bfd_byte temp[4]; + bfd_vma val; + const char *name; + + if (bfd_bread (temp, (bfd_size_type) sizeof (temp), abfd) != sizeof (temp)) + return FALSE; + + val = bfd_get_32 (abfd, temp); + + /* The value is an offset into either the code or data segment. + This is the location which needs to be adjusted. + + If this is a relocation fixup rather than an imported symbol (the + sym argument is NULL) then the high bit is 0 if the location + needs to be adjusted by the address of the data segment, or 1 if + the location needs to be adjusted by the address of the code + segment. If this is an imported symbol, then the high bit is 0 + if the location is 0 if the location should be adjusted by the + offset to the symbol, or 1 if the location should adjusted by the + absolute value of the symbol. + + The second most significant bit is 0 if the value is an offset + into the data segment, or 1 if the value is an offset into the + code segment. + + All this translates fairly easily into a BFD reloc. */ + + if (sym == NULL) + { + if ((val & NLM_HIBIT) == 0) + name = NLM_INITIALIZED_DATA_NAME; + else + { + name = NLM_CODE_NAME; + val &=~ NLM_HIBIT; + } + rel->sym_ptr_ptr = bfd_get_section_by_name (abfd, name)->symbol_ptr_ptr; + rel->howto = &nlm_i386_abs_howto; + } + else + { + /* In this case we do not need to set the sym_ptr_ptr field. */ + rel->sym_ptr_ptr = NULL; + if ((val & NLM_HIBIT) == 0) + rel->howto = &nlm_i386_pcrel_howto; + else + { + rel->howto = &nlm_i386_abs_howto; + val &=~ NLM_HIBIT; + } + } + + if ((val & (NLM_HIBIT >> 1)) == 0) + *secp = bfd_get_section_by_name (abfd, NLM_INITIALIZED_DATA_NAME); + else + { + *secp = bfd_get_section_by_name (abfd, NLM_CODE_NAME); + val &=~ (NLM_HIBIT >> 1); + } + + rel->address = val; + rel->addend = 0; + + return TRUE; +} + +/* Write a NetWare i386 reloc. */ + +static bfd_boolean +nlm_i386_write_import (bfd * abfd, asection * sec, arelent * rel) +{ + asymbol *sym; + bfd_vma val; + bfd_byte temp[4]; + + /* NetWare only supports two kinds of relocs. We should check + special_function here, as well, but at the moment coff-i386 + relocs uses a special_function which does not affect what we do + here. */ + if (rel->addend != 0 + || rel->howto == NULL + || rel->howto->rightshift != 0 + || rel->howto->size != 2 + || rel->howto->bitsize != 32 + || rel->howto->bitpos != 0 + || rel->howto->src_mask != 0xffffffff + || rel->howto->dst_mask != 0xffffffff) + { + bfd_set_error (bfd_error_invalid_operation); + return FALSE; + } + + sym = *rel->sym_ptr_ptr; + + /* The value we write out is the offset into the appropriate + segment. This offset is the section vma, adjusted by the vma of + the lowest section in that segment, plus the address of the + relocation. */ + val = bfd_get_section_vma (abfd, sec) + rel->address; + + /* The second most significant bit is 0 if the value is an offset + into the data segment, or 1 if the value is an offset into the + code segment. */ + if (bfd_get_section_flags (abfd, sec) & SEC_CODE) + { + val -= nlm_get_text_low (abfd); + val |= NLM_HIBIT >> 1; + } + else + val -= nlm_get_data_low (abfd); + + if (! bfd_is_und_section (bfd_get_section (sym))) + { + /* NetWare only supports absolute internal relocs. */ + if (rel->howto->pc_relative) + { + bfd_set_error (bfd_error_invalid_operation); + return FALSE; + } + + /* The high bit is 1 if the reloc is against the code section, 0 + if against the data section. */ + if (bfd_get_section_flags (abfd, bfd_get_section (sym)) & SEC_CODE) + val |= NLM_HIBIT; + } + else + { + /* The high bit is 1 if this is an absolute reloc, 0 if it is PC + relative. */ + if (! rel->howto->pc_relative) + val |= NLM_HIBIT; + else + { + /* PC relative relocs on NetWare must be pcrel_offset. */ + if (! rel->howto->pcrel_offset) + { + bfd_set_error (bfd_error_invalid_operation); + return FALSE; + } + } + } + + bfd_put_32 (abfd, val, temp); + if (bfd_bwrite (temp, (bfd_size_type) sizeof (temp), abfd) != sizeof (temp)) + return FALSE; + + return TRUE; +} + +/* I want to be able to use objcopy to turn an i386 a.out or COFF file + into a NetWare i386 module. That means that the relocs from the + source file have to be mapped into relocs that apply to the target + file. This function is called by nlm_set_section_contents to give + it a chance to rework the relocs. + + This is actually a fairly general concept. However, this is not a + general implementation. */ + +static bfd_boolean +nlm_i386_mangle_relocs (bfd *abfd, + asection *sec, + const void * data, + bfd_vma offset, + bfd_size_type count) +{ + arelent **rel_ptr_ptr, **rel_end; + + rel_ptr_ptr = sec->orelocation; + rel_end = rel_ptr_ptr + sec->reloc_count; + for (; rel_ptr_ptr < rel_end; rel_ptr_ptr++) + { + arelent *rel; + asymbol *sym; + bfd_vma addend; + + rel = *rel_ptr_ptr; + sym = *rel->sym_ptr_ptr; + + /* Note that no serious harm will ensue if we fail to change a + reloc. We will wind up failing in nlm_i386_write_import. */ + + /* Make sure this reloc is within the data we have. We only 4 + byte relocs here, so we insist on having 4 bytes. */ + if (rel->address < offset + || rel->address + 4 > offset + count) + continue; + + /* NetWare doesn't support reloc addends, so we get rid of them + here by simply adding them into the object data. We handle + the symbol value, if any, the same way. */ + addend = rel->addend + sym->value; + + /* The value of a symbol is the offset into the section. If the + symbol is in the .bss segment, we need to include the size of + the data segment in the offset as well. Fortunately, we know + that at this point the size of the data section is in the NLM + header. */ + if (((bfd_get_section_flags (abfd, bfd_get_section (sym)) + & SEC_LOAD) == 0) + && ((bfd_get_section_flags (abfd, bfd_get_section (sym)) + & SEC_ALLOC) != 0)) + addend += nlm_fixed_header (abfd)->dataImageSize; + + if (addend != 0 + && rel->howto != NULL + && rel->howto->rightshift == 0 + && rel->howto->size == 2 + && rel->howto->bitsize == 32 + && rel->howto->bitpos == 0 + && rel->howto->src_mask == 0xffffffff + && rel->howto->dst_mask == 0xffffffff) + { + bfd_vma val; + + val = bfd_get_32 (abfd, (bfd_byte *) data + rel->address - offset); + val += addend; + bfd_put_32 (abfd, val, (bfd_byte *) data + rel->address - offset); + rel->addend = 0; + } + + /* NetWare uses a reloc with pcrel_offset set. We adjust + pc_relative relocs accordingly. We are going to change the + howto field, so we can only do this if the current one is + compatible. We should check special_function here, but at + the moment coff-i386 uses a special_function which does not + affect what we are doing here. */ + if (rel->howto != NULL + && rel->howto->pc_relative + && ! rel->howto->pcrel_offset + && rel->howto->rightshift == 0 + && rel->howto->size == 2 + && rel->howto->bitsize == 32 + && rel->howto->bitpos == 0 + && rel->howto->src_mask == 0xffffffff + && rel->howto->dst_mask == 0xffffffff) + { + bfd_vma val; + + /* When pcrel_offset is not set, it means that the negative + of the address of the memory location is stored in the + memory location. We must add it back in. */ + val = bfd_get_32 (abfd, (bfd_byte *) data + rel->address - offset); + val += rel->address; + bfd_put_32 (abfd, val, (bfd_byte *) data + rel->address - offset); + + rel->howto = &nlm_i386_pcrel_howto; + } + } + + return TRUE; +} + +/* Read a NetWare i386 import record. */ + +static bfd_boolean +nlm_i386_read_import (bfd * abfd, nlmNAME (symbol_type) * sym) +{ + struct nlm_relent *nlm_relocs; /* Relocation records for symbol. */ + bfd_size_type rcount; /* Number of relocs. */ + bfd_byte temp[NLM_TARGET_LONG_SIZE]; /* Temporary 32-bit value. */ + unsigned char symlength; /* Length of symbol name. */ + char *name; + + if (bfd_bread (& symlength, (bfd_size_type) sizeof (symlength), abfd) + != sizeof (symlength)) + return FALSE; + sym -> symbol.the_bfd = abfd; + name = bfd_alloc (abfd, (bfd_size_type) symlength + 1); + if (name == NULL) + return FALSE; + if (bfd_bread (name, (bfd_size_type) symlength, abfd) != symlength) + return FALSE; + name[symlength] = '\0'; + sym -> symbol.name = name; + sym -> symbol.flags = 0; + sym -> symbol.value = 0; + sym -> symbol.section = bfd_und_section_ptr; + if (bfd_bread (temp, (bfd_size_type) sizeof (temp), abfd) != sizeof (temp)) + return FALSE; + rcount = H_GET_32 (abfd, temp); + nlm_relocs = bfd_alloc (abfd, rcount * sizeof (struct nlm_relent)); + if (!nlm_relocs) + return FALSE; + sym -> relocs = nlm_relocs; + sym -> rcnt = 0; + while (sym -> rcnt < rcount) + { + asection *section; + + if (! nlm_i386_read_reloc (abfd, sym, §ion, &nlm_relocs -> reloc)) + return FALSE; + nlm_relocs -> section = section; + nlm_relocs++; + sym -> rcnt++; + } + return TRUE; +} + +/* Write out an external reference. */ + +static bfd_boolean +nlm_i386_write_external (bfd *abfd, + bfd_size_type count, + asymbol *sym, + struct reloc_and_sec *relocs) +{ + unsigned int i; + bfd_byte len; + unsigned char temp[NLM_TARGET_LONG_SIZE]; + + len = strlen (sym->name); + if ((bfd_bwrite (&len, (bfd_size_type) sizeof (bfd_byte), abfd) + != sizeof (bfd_byte)) + || bfd_bwrite (sym->name, (bfd_size_type) len, abfd) != len) + return FALSE; + + bfd_put_32 (abfd, count, temp); + if (bfd_bwrite (temp, (bfd_size_type) sizeof (temp), abfd) != sizeof (temp)) + return FALSE; + + for (i = 0; i < count; i++) + if (! nlm_i386_write_import (abfd, relocs[i].sec, relocs[i].rel)) + return FALSE; + + return TRUE; +} + +#include "nlmswap.h" + +static const struct nlm_backend_data nlm32_i386_backend = +{ + "NetWare Loadable Module\032", + sizeof (Nlm32_i386_External_Fixed_Header), + 0, /* Optional_prefix_size. */ + bfd_arch_i386, + 0, + FALSE, + 0, /* Backend_object_p. */ + 0, /* Write_prefix_func. */ + nlm_i386_read_reloc, + nlm_i386_mangle_relocs, + nlm_i386_read_import, + nlm_i386_write_import, + 0, /* Set_public_section. */ + 0, /* Set_public_offset. */ + nlm_swap_fixed_header_in, + nlm_swap_fixed_header_out, + nlm_i386_write_external, + 0, /* Write_export. */ +}; + +#define TARGET_LITTLE_NAME "nlm32-i386" +#define TARGET_LITTLE_SYM nlmNAME (i386_vec) +#define TARGET_BACKEND_DATA & nlm32_i386_backend + +#include "nlm-target.h" |