diff options
Diffstat (limited to 'ld/pe-dll.c')
-rw-r--r-- | ld/pe-dll.c | 339 |
1 files changed, 213 insertions, 126 deletions
diff --git a/ld/pe-dll.c b/ld/pe-dll.c index c087bf2..ad0ffcf 100644 --- a/ld/pe-dll.c +++ b/ld/pe-dll.c @@ -168,7 +168,7 @@ static struct bfd_section *edata_s, *reloc_s; static unsigned char *edata_d, *reloc_d; static size_t edata_sz, reloc_sz; static int runtime_pseudo_relocs_created = 0; -static int runtime_pseudp_reloc_v2_init = 0; +static bfd_boolean runtime_pseudp_reloc_v2_init = FALSE; typedef struct { @@ -1287,10 +1287,12 @@ fill_edata (bfd *abfd, struct bfd_link_info *info ATTRIBUTE_UNUSED) static struct bfd_section *current_sec; -void -pe_walk_relocs_of_symbol (struct bfd_link_info *info, - char *name, - int (*cb) (arelent *, asection *, char *)) +static void +pe_walk_relocs (struct bfd_link_info *info, + char *name, + const char *symname, + struct bfd_hash_table *import_hash, + void (*cb) (arelent *, asection *, char *, const char *)) { bfd *b; asection *s; @@ -1328,8 +1330,20 @@ pe_walk_relocs_of_symbol (struct bfd_link_info *info, { struct bfd_symbol *sym = *relocs[i]->sym_ptr_ptr; - if (!strcmp (name, sym->name)) - cb (relocs[i], s, name); + /* Warning: the callback needs to be passed NAME directly. */ + if (import_hash) + { + if (bfd_hash_lookup (import_hash, sym->name, FALSE, FALSE)) + { + strcpy (name, sym->name); + cb (relocs[i], s, name, symname); + } + } + else + { + if (strcmp (name, sym->name) == 0) + cb (relocs[i], s, name, symname); + } } free (relocs); @@ -1341,6 +1355,138 @@ pe_walk_relocs_of_symbol (struct bfd_link_info *info, } } +void +pe_find_data_imports (const char *symhead, + void (*cb) (arelent *, asection *, char *, const char *)) +{ + struct bfd_link_hash_entry *undef; + const size_t headlen = strlen (symhead); + size_t namelen = 0; + char *buf, *name; + struct bfd_hash_table *import_hash; + + for (undef = link_info.hash->undefs; undef; undef = undef->u.undef.next) + if (undef->type == bfd_link_hash_undefined) + { + size_t len = strlen (undef->root.string); + if (namelen < len) + namelen = len; + } + if (namelen == 0) + return; + + /* For the pseudo-relocation support version 2, we can collect the symbols + that are subject to auto-import and adjust the relocations en masse. */ + if (link_info.pei386_runtime_pseudo_reloc == 2) + { + import_hash + = (struct bfd_hash_table *) xmalloc (sizeof (struct bfd_hash_table)); + if (!bfd_hash_table_init (import_hash, + bfd_hash_newfunc, + sizeof (struct bfd_hash_entry))) + einfo (_("%F%P: bfd_hash_table_init failed: %E\n")); + } + else + import_hash = NULL; + + /* We are being a bit cunning here. The buffer will have space for + prefixes at the beginning. The prefix is modified here and in a + number of functions called from this function. */ +#define PREFIX_LEN 32 + buf = xmalloc (PREFIX_LEN + namelen + 1); + name = buf + PREFIX_LEN; + + for (undef = link_info.hash->undefs; undef; undef = undef->u.undef.next) + if (undef->type == bfd_link_hash_undefined) + { + struct bfd_link_hash_entry *sym; + char *impname; + + if (pe_dll_extra_pe_debug) + printf ("%s:%s\n", __FUNCTION__, undef->root.string); + + strcpy (name, undef->root.string); + impname = name - (sizeof "__imp_" - 1); + memcpy (impname, "__imp_", sizeof "__imp_" - 1); + + sym = bfd_link_hash_lookup (link_info.hash, impname, 0, 0, 1); + + if (sym && sym->type == bfd_link_hash_defined) + { + if (import_hash) + bfd_hash_lookup (import_hash, undef->root.string, TRUE, FALSE); + else + { + bfd *b = sym->u.def.section->owner; + const char *symname = NULL; + asymbol **symbols; + int nsyms, i; + + if (!bfd_generic_link_read_symbols (b)) + { + einfo (_("%F%P: %pB: could not read symbols: %E\n"), b); + return; + } + + symbols = bfd_get_outsymbols (b); + nsyms = bfd_get_symcount (b); + + for (i = 0; i < nsyms; i++) + if (strncmp (symbols[i]->name, symhead, headlen) == 0) + { + if (pe_dll_extra_pe_debug) + printf ("->%s\n", symbols[i]->name); + + symname = symbols[i]->name + headlen; + break; + } + + /* If the symobl isn't part of an import table, there is no + point in building a fixup, this would give rise to link + errors for mangled symbols instead of the original one. */ + if (symname) + pe_walk_relocs (&link_info, name, symname, NULL, cb); + else + continue; + } + + /* Let's differentiate it somehow from defined. */ + undef->type = bfd_link_hash_defweak; + undef->u.def.value = sym->u.def.value; + undef->u.def.section = sym->u.def.section; + + if (link_info.pei386_auto_import == -1) + { + static bfd_boolean warned = FALSE; + + info_msg (_("Info: resolving %s by linking to %s " + "(auto-import)\n"), name, impname); + + /* PR linker/4844. */ + if (!warned) + { + einfo (_("%P: warning: auto-importing has been activated " + "without --enable-auto-import specified on the " + "command line; this should work unless it " + "involves constant data structures referencing " + "symbols from auto-imported DLLs\n")); + warned = TRUE; + } + } + } + } + + /* If we have the import hash table, walk the relocations only once. */ + if (import_hash) + { + pe_walk_relocs (&link_info, name, NULL, import_hash, cb); + bfd_hash_table_free (import_hash); + free (import_hash); + } + + free (buf); +} + /* Gather all the relocations and build the .reloc section. */ static void @@ -1794,7 +1940,6 @@ pe_dll_generate_def_file (const char *pe_out_def_filename) static asymbol **symtab; static int symptr; static int tmp_seq; -static int tmp_seq2; static const char *dll_filename; static char *dll_symname; @@ -2327,47 +2472,6 @@ make_one (def_file_export *exp, bfd *parent, bfd_boolean include_jmp_stub) } static bfd * -make_singleton_name_imp (const char *import, bfd *parent) -{ - /* Name thunks go to idata$4. */ - asection *id5; - unsigned char *d5; - char *oname; - bfd *abfd; - - oname = xmalloc (20); - sprintf (oname, "nmimp%06d.o", tmp_seq2); - tmp_seq2++; - - abfd = bfd_create (oname, parent); - bfd_find_target (pe_details->object_target, abfd); - bfd_make_writable (abfd); - - bfd_set_format (abfd, bfd_object); - bfd_set_arch_mach (abfd, pe_details->bfd_arch, 0); - - symptr = 0; - symtab = xmalloc (3 * sizeof (asymbol *)); - id5 = quick_section (abfd, ".idata$5", SEC_HAS_CONTENTS, 2); - quick_symbol (abfd, "__imp_", import, "", id5, BSF_GLOBAL, 0); - - /* We need space for the real thunk and for the null terminator. */ - bfd_set_section_size (abfd, id5, PE_IDATA5_SIZE * 2); - d5 = xmalloc (PE_IDATA5_SIZE * 2); - id5->contents = d5; - memset (d5, 0, PE_IDATA5_SIZE * 2); - quick_reloc (abfd, 0, BFD_RELOC_RVA, 2); - save_relocs (id5); - - bfd_set_symtab (abfd, symtab, symptr); - - bfd_set_section_contents (abfd, id5, d5, 0, PE_IDATA4_SIZE * 2); - - bfd_make_readable (abfd); - return abfd; -} - -static bfd * make_singleton_name_thunk (const char *import, bfd *parent) { /* Name thunks go to idata$4. */ @@ -2409,7 +2513,7 @@ make_singleton_name_thunk (const char *import, bfd *parent) return abfd; } -static char * +static const char * make_import_fixup_mark (arelent *rel, char *name) { /* We convert reloc to symbol, for later reference. */ @@ -2431,7 +2535,7 @@ make_import_fixup_mark (arelent *rel, char *name) current_sec, /* sym->section, */ rel->address, NULL, TRUE, FALSE, &bh); - return fixup_name; + return bh->root.string; } /* .section .idata$2 @@ -2469,12 +2573,7 @@ make_import_fixup_entry (const char *name, quick_symbol (abfd, "__nm_thnk_", name, "", UNDSEC, BSF_GLOBAL, 0); quick_symbol (abfd, U (""), symname, "_iname", UNDSEC, BSF_GLOBAL, 0); - /* For relocator v2 we have to use the .idata$5 element and not - fixup_name. */ - if (link_info.pei386_runtime_pseudo_reloc == 2) - quick_symbol (abfd, "__imp_", name, "", UNDSEC, BSF_GLOBAL, 0); - else - quick_symbol (abfd, "", fixup_name, "", UNDSEC, BSF_GLOBAL, 0); + quick_symbol (abfd, "", fixup_name, "", UNDSEC, BSF_GLOBAL, 0); bfd_set_section_size (abfd, id2, 20); d2 = xmalloc (20); @@ -2509,6 +2608,8 @@ make_runtime_pseudo_reloc (const char *name ATTRIBUTE_UNUSED, unsigned char *rt_rel_d; char *oname; bfd *abfd; + bfd_size_type size; + oname = xmalloc (20); sprintf (oname, "rtr%06d.o", tmp_seq); tmp_seq++; @@ -2520,47 +2621,52 @@ make_runtime_pseudo_reloc (const char *name ATTRIBUTE_UNUSED, bfd_set_format (abfd, bfd_object); bfd_set_arch_mach (abfd, pe_details->bfd_arch, 0); - symptr = 0; if (link_info.pei386_runtime_pseudo_reloc == 2) { - symtab = xmalloc ((runtime_pseudp_reloc_v2_init ? 3 : 6) * sizeof (asymbol *)); + if (runtime_pseudp_reloc_v2_init) + size = 3 * sizeof (asymbol *); + else + size = 6 * sizeof (asymbol *); } else - { - symtab = xmalloc (2 * sizeof (asymbol *)); - } - rt_rel = quick_section (abfd, ".rdata_runtime_pseudo_reloc", - SEC_HAS_CONTENTS, 2); + size = 2 * sizeof (asymbol *); + + symptr = 0; + symtab = xmalloc (size); + + rt_rel + = quick_section (abfd, ".rdata_runtime_pseudo_reloc", SEC_HAS_CONTENTS, 2); quick_symbol (abfd, "", fixup_name, "", UNDSEC, BSF_GLOBAL, 0); if (link_info.pei386_runtime_pseudo_reloc == 2) { - size_t size = 12; - if (! runtime_pseudp_reloc_v2_init) - { - size += 12; - runtime_pseudp_reloc_v2_init = 1; - } + size = 12; + if (!runtime_pseudp_reloc_v2_init) + { + size += 12; + runtime_pseudp_reloc_v2_init = TRUE; + } + quick_symbol (abfd, "__imp_", name, "", UNDSEC, BSF_GLOBAL, 0); bfd_set_section_size (abfd, rt_rel, size); rt_rel_d = xmalloc (size); rt_rel->contents = rt_rel_d; memset (rt_rel_d, 0, size); - quick_reloc (abfd, size - 8, BFD_RELOC_RVA, 1); - quick_reloc (abfd, size - 12, BFD_RELOC_RVA, 2); - bfd_put_32 (abfd, bitsize, rt_rel_d + (size - 4)); - if (size != 12) - bfd_put_32 (abfd, 1, rt_rel_d + 8); + quick_reloc (abfd, size - 8, BFD_RELOC_RVA, 1); + quick_reloc (abfd, size - 12, BFD_RELOC_RVA, 2); + bfd_put_32 (abfd, bitsize, rt_rel_d + (size - 4)); + if (size != 12) + bfd_put_32 (abfd, 1, rt_rel_d + 8); save_relocs (rt_rel); bfd_set_symtab (abfd, symtab, symptr); bfd_set_section_contents (abfd, rt_rel, rt_rel_d, 0, size); - } + } else - { + { bfd_set_section_size (abfd, rt_rel, 8); rt_rel_d = xmalloc (8); rt_rel->contents = rt_rel_d; @@ -2575,6 +2681,7 @@ make_runtime_pseudo_reloc (const char *name ATTRIBUTE_UNUSED, bfd_set_section_contents (abfd, rt_rel, rt_rel_d, 0, 8); } + bfd_make_readable (abfd); return abfd; } @@ -2624,65 +2731,46 @@ pe_create_runtime_relocator_reference (bfd *parent) } void -pe_create_import_fixup (arelent *rel, asection *s, bfd_vma addend, char *name) +pe_create_import_fixup (arelent *rel, asection *s, bfd_vma addend, char *name, + const char *symname) { - struct bfd_symbol *sym = *rel->sym_ptr_ptr; - struct bfd_link_hash_entry *name_thunk_sym; - struct bfd_link_hash_entry *name_imp_sym; - char *fixup_name, *impname; + const char *fixup_name = make_import_fixup_mark (rel, name); bfd *b; - int need_import_table = 1; - - /* name buffer is allocated with space at beginning for prefixes. */ - impname = name - (sizeof "__imp_" - 1); - memcpy (impname, "__imp_", sizeof "__imp_" - 1); - name_imp_sym = bfd_link_hash_lookup (link_info.hash, impname, 0, 0, 1); - impname = name - (sizeof "__nm_thnk_" - 1); - memcpy (impname, "__nm_thnk_", sizeof "__nm_thnk_" - 1); - name_thunk_sym = bfd_link_hash_lookup (link_info.hash, impname, 0, 0, 1); - - fixup_name = make_import_fixup_mark (rel, name); - - /* For version 2 pseudo relocation we don't need to add an import - if the import symbol is already present. */ - if (link_info.pei386_runtime_pseudo_reloc == 2 - && name_imp_sym - && name_imp_sym->type == bfd_link_hash_defined) - need_import_table = 0; - - if (need_import_table == 1 - && (!name_thunk_sym || name_thunk_sym->type != bfd_link_hash_defined)) + /* This is the original implementation of the auto-import feature, which + primarily relied on the OS loader to patch things up with some help + from the pseudo-relocator to overcome the main limitation. See the + comment at the beginning of the file for an overview of the feature. */ + if (link_info.pei386_runtime_pseudo_reloc != 2) { - b = make_singleton_name_thunk (name, link_info.output_bfd); - add_bfd_to_link (b, b->filename, &link_info); + struct bfd_link_hash_entry *name_thunk_sym; + /* name buffer is allocated with space at beginning for prefixes. */ + char *thname = name - (sizeof "__nm_thnk_" - 1); + memcpy (thname, "__nm_thnk_", sizeof "__nm_thnk_" - 1); + name_thunk_sym = bfd_link_hash_lookup (link_info.hash, thname, 0, 0, 1); - /* If we ever use autoimport, we have to cast text section writable. - But not for version 2. */ - if (link_info.pei386_runtime_pseudo_reloc != 2) + if (!(name_thunk_sym && name_thunk_sym->type == bfd_link_hash_defined)) { + b = make_singleton_name_thunk (name, link_info.output_bfd); + add_bfd_to_link (b, b->filename, &link_info); + + /* If we ever use autoimport, we have to cast text section writable. */ config.text_read_only = FALSE; link_info.output_bfd->flags &= ~WP_TEXT; } - if (link_info.pei386_runtime_pseudo_reloc == 2) + + if (addend == 0 || link_info.pei386_runtime_pseudo_reloc == 1) { - b = make_singleton_name_imp (name, link_info.output_bfd); + b = make_import_fixup_entry (name, fixup_name, symname, + link_info.output_bfd); add_bfd_to_link (b, b->filename, &link_info); } } - if ((addend == 0 || link_info.pei386_runtime_pseudo_reloc) - && need_import_table == 1) - { - extern char * pe_data_import_dll; - char * symname = pe_data_import_dll ? pe_data_import_dll : "unknown"; - - b = make_import_fixup_entry (name, fixup_name, symname, - link_info.output_bfd); - add_bfd_to_link (b, b->filename, &link_info); - } - - if ((link_info.pei386_runtime_pseudo_reloc != 0 && addend != 0) + /* In the original implementation, the pseudo-relocator was only used when + the addend was not null. In the new implementation, the OS loader is + completely bypassed and the pseudo-relocator does the entire work. */ + if ((addend != 0 && link_info.pei386_runtime_pseudo_reloc == 1) || link_info.pei386_runtime_pseudo_reloc == 2) { if (pe_dll_extra_pe_debug) @@ -2693,19 +2781,18 @@ pe_create_import_fixup (arelent *rel, asection *s, bfd_vma addend, char *name) link_info.output_bfd); add_bfd_to_link (b, b->filename, &link_info); - if (runtime_pseudo_relocs_created == 0) + if (runtime_pseudo_relocs_created++ == 0) { b = pe_create_runtime_relocator_reference (link_info.output_bfd); add_bfd_to_link (b, b->filename, &link_info); } - runtime_pseudo_relocs_created++; } + else if (addend != 0) einfo (_("%X%P: %C: variable '%pT' can't be auto-imported; please read the documentation for ld's --enable-auto-import for details\n"), - s->owner, s, rel->address, sym->name); + s->owner, s, rel->address, (*rel->sym_ptr_ptr)->name); } - void pe_dll_generate_implib (def_file *def, const char *impfilename, struct bfd_link_info *info) { |