/* coffgrok.c Copyright (C) 1994-2023 Free Software Foundation, Inc. This file is part of GNU Binutils. 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. */ /* Written by Steve Chamberlain (sac@cygnus.com) This module reads a coff file and builds a really simple type tree which can be read by other programs. The first application is a coff->sysroff converter. It can be tested with coffdump.c. */ #include "sysdep.h" #include "bfd.h" #include "libiberty.h" #include "coff/internal.h" #include "../bfd/libcoff.h" #include "bucomm.h" #include "coffgrok.h" static int lofile = 1; static struct coff_scope * top_scope; static struct coff_scope * file_scope; static struct coff_ofile * ofile; static struct coff_symbol * last_function_symbol; static struct coff_type * last_function_type; static struct coff_type * last_struct; static struct coff_type * last_enum; static struct coff_sfile * cur_sfile; static struct coff_symbol ** tindex; static asymbol ** syms; static long symcount; static struct coff_ptr_struct * rawsyms; static unsigned int rawcount; static bfd * abfd; #define N(x) ((x)->_n._n_nptr[1]) #define PTR_SIZE 4 #define SHORT_SIZE 2 #define INT_SIZE 4 #define LONG_SIZE 4 #define FLOAT_SIZE 4 #define DOUBLE_SIZE 8 #define INDEXOF(p) ((struct coff_ptr_struct *)(p)-(rawsyms)) static struct coff_scope * empty_scope (void) { return (struct coff_scope *) (xcalloc (sizeof (struct coff_scope), 1)); } static struct coff_symbol * empty_symbol (void) { return (struct coff_symbol *) (xcalloc (sizeof (struct coff_symbol), 1)); } static void push_scope (int slink) { struct coff_scope *n = empty_scope (); if (slink) { if (top_scope) { if (top_scope->list_tail) { top_scope->list_tail->next = n; } else { top_scope->list_head = n; } top_scope->list_tail = n; } } n->parent = top_scope; top_scope = n; } static void pop_scope (void) { /* PR 17512: file: 809933ac. */ if (top_scope == NULL) fatal (_("Out of context scope change encountered")); top_scope = top_scope->parent; } static void do_sections_p1 (struct coff_ofile *head) { asection *section; int idx; struct coff_section *all = (struct coff_section *) (xcalloc (abfd->section_count + 1, sizeof (struct coff_section))); head->nsections = abfd->section_count + 1; head->sections = all; for (idx = 0, section = abfd->sections; section; section = section->next, idx++) { long relsize; unsigned int i = section->target_index; arelent **relpp; long relcount; /* PR 17512: file: 2d6effca. */ if (i > abfd->section_count) fatal (_("Invalid section target index: %u"), i); relsize = bfd_get_reloc_upper_bound (abfd, section); if (relsize < 0) bfd_fatal (bfd_get_filename (abfd)); if (relsize == 0) continue; relpp = (arelent **) xmalloc (relsize); relcount = bfd_canonicalize_reloc (abfd, section, relpp, syms); if (relcount < 0) bfd_fatal (bfd_get_filename (abfd)); head->sections[i].name = (char *) (section->name); head->sections[i].code = section->flags & SEC_CODE; head->sections[i].data = section->flags & SEC_DATA; if (strcmp (section->name, ".bss") == 0) head->sections[i].data = 1; head->sections[i].address = section->lma; head->sections[i].size = bfd_section_size (section); head->sections[i].number = idx; head->sections[i].nrelocs = section->reloc_count; head->sections[i].relocs = (struct coff_reloc *) (xcalloc (section->reloc_count, sizeof (struct coff_reloc))); head->sections[i].bfd_section = section; } head->sections[0].name = "ABSOLUTE"; head->sections[0].code = 0; head->sections[0].data = 0; head->sections[0].address = 0; head->sections[0].size = 0; head->sections[0].number = 0; } static void do_sections_p2 (struct coff_ofile *head) { asection *section; for (section = abfd->sections; section; section = section->next) { unsigned int j; /* PR 17512: file: 7c1a36e8. A corrupt COFF binary might have a reloc count but no relocs. Handle this here. */ if (section->relocation == NULL) continue; for (j = 0; j < section->reloc_count; j++) { unsigned int idx; int i = section->target_index; struct coff_reloc *r; arelent *sr = section->relocation + j; if (i > head->nsections) fatal (_("Invalid section target index: %d"), i); /* PR 17512: file: db850ff4. */ if (j >= head->sections[i].nrelocs) fatal (_("Target section has insufficient relocs")); r = head->sections[i].relocs + j; r->offset = sr->address; r->addend = sr->addend; idx = ((coff_symbol_type *) (sr->sym_ptr_ptr[0]))->native - rawsyms; if (idx >= rawcount) { if (rawcount == 0) fatal (_("Symbol index %u encountered when there are no symbols"), idx); non_fatal (_("Invalid symbol index %u encountered"), idx); idx = 0; } r->symbol = tindex[idx]; } } } static struct coff_where * do_where (unsigned int i) { struct internal_syment *sym; struct coff_where *where = (struct coff_where *) (xmalloc (sizeof (struct coff_where))); if (i >= rawcount) fatal ("Invalid symbol index: %d\n", i); sym = &rawsyms[i].u.syment; where->offset = sym->n_value; if (sym->n_scnum == -1) sym->n_scnum = 0; switch (sym->n_sclass) { case C_FIELD: where->where = coff_where_member_of_struct; where->offset = sym->n_value / 8; where->bitoffset = sym->n_value % 8; where->bitsize = rawsyms[i + 1].u.auxent.x_sym.x_misc.x_lnsz.x_size; break; case C_MOE: where->where = coff_where_member_of_enum; break; case C_MOS: case C_MOU: where->where = coff_where_member_of_struct; break; case C_AUTO: case C_ARG: where->where = coff_where_stack; break; case C_EXT: case C_STAT: case C_EXTDEF: case C_LABEL: where->where = coff_where_memory; /* PR 17512: file: 07a37c40. */ /* PR 17512: file: 0c2eb101. */ if (sym->n_scnum >= ofile->nsections || sym->n_scnum < 0) { non_fatal (_("Invalid section number (%d) encountered"), sym->n_scnum); where->section = ofile->sections; } else where->section = &ofile->sections[sym->n_scnum]; break; case C_REG: case C_REGPARM: where->where = coff_where_register; break; case C_ENTAG: where->where = coff_where_entag; break; case C_STRTAG: case C_UNTAG: where->where = coff_where_strtag; break; case C_TPDEF: where->where = coff_where_typedef; break; default: fatal (_("Unrecognized symbol class: %d"), sym->n_sclass); break; } return where; } static struct coff_line * do_lines (int i, char *name ATTRIBUTE_UNUSED) { struct coff_line *res = (struct coff_line *) xcalloc (sizeof (struct coff_line), 1); asection *s; unsigned int l; /* Find out if this function has any line numbers in the table. */ for (s = abfd->sections; s; s = s->next) { /* PR 17512: file: 07a37c40. A corrupt COFF binary can have a linenumber count in the header but no line number table. This should be reported elsewhere, but do not rely upon this. */ if (s->lineno == NULL) continue; for (l = 0; l < s->lineno_count; l++) { if (s->lineno[l].line_number == 0) { if (rawsyms + i == ((coff_symbol_type *) (&(s->lineno[l].u.sym[0])))->native) { /* These lines are for this function - so count them and stick them on. */ int c = 0; /* Find the linenumber of the top of the function, since coff linenumbers are relative to the start of the function. */ int start_line = rawsyms[i + 3].u.auxent.x_sym.x_misc.x_lnsz.x_lnno; l++; for (c = 0; /* PR 17512: file: c2825452. */ l + c + 1 < s->lineno_count && s->lineno[l + c + 1].line_number; c++) ; /* Add two extra records, one for the prologue and one for the epilogue. */ c += 1; res->nlines = c; res->lines = (int *) (xcalloc (sizeof (int), c)); res->addresses = (int *) (xcalloc (sizeof (int), c)); res->lines[0] = start_line; res->addresses[0] = rawsyms[i].u.syment.n_value - s->vma; for (c = 0; /* PR 17512: file: c2825452. */ l + c + 1 < s->lineno_count && s->lineno[l + c + 1].line_number; c++) { res->lines[c + 1] = s->lineno[l + c].line_number + start_line - 1; res->addresses[c + 1] = s->lineno[l + c].u.offset; } return res; } } } } return res; } static struct coff_type * do_type (unsigned int i) { struct internal_syment *sym; combined_entry_type *aux; struct coff_type *res = (struct coff_type *) xmalloc (sizeof (struct coff_type)); int type; int which_dt = 0; int dimind = 0; if (i >= rawcount) fatal (_("Type entry %u does not have enough symbolic information"), i); if (!rawsyms[i].is_sym) fatal (_("Type entry %u does not refer to a symbol"), i); sym = &rawsyms[i].u.syment; if (sym->n_numaux == 0 || i >= rawcount -1 || rawsyms[i + 1].is_sym) aux = NULL; else aux = &rawsyms[i + 1]; type = sym->n_type; res->type = coff_basic_type; res->u.basic = type & 0xf; switch (type & 0xf) { case T_NULL: case T_VOID: if (sym->n_numaux && sym->n_sclass == C_STAT) { /* This is probably a section definition. */ res->type = coff_secdef_type; if (aux == NULL) fatal (_("Section definition needs a section length")); res->size = aux->u.auxent.x_scn.x_scnlen; /* PR 17512: file: 081c955d. Fill in the asecdef structure as well. */ res->u.asecdef.address = 0; res->u.asecdef.size = 0; } else { if (type == 0) { /* Don't know what this is, let's make it a simple int. */ res->size = INT_SIZE; res->u.basic = T_UINT; } else { /* Else it could be a function or pointer to void. */ res->size = 0; } } break; case T_UCHAR: case T_CHAR: res->size = 1; break; case T_USHORT: case T_SHORT: res->size = SHORT_SIZE; break; case T_UINT: case T_INT: res->size = INT_SIZE; break; case T_ULONG: case T_LONG: res->size = LONG_SIZE; break; case T_FLOAT: res->size = FLOAT_SIZE; break; case T_DOUBLE: res->size = DOUBLE_SIZE; break; case T_STRUCT: case T_UNION: if (sym->n_numaux) { if (aux == NULL) fatal (_("Aggregate definition needs auxiliary information")); if (aux->fix_tag) { unsigned int idx = INDEXOF (aux->u.auxent.x_sym.x_tagndx.p); /* Referring to a struct defined elsewhere. */ res->type = coff_structref_type; res->u.astructref.ref = tindex[idx]; res->size = res->u.astructref.ref ? res->u.astructref.ref->type->size : 0; } else { /* A definition of a struct. */ last_struct = res; res->type = coff_structdef_type; res->u.astructdef.elements = empty_scope (); res->u.astructdef.idx = 0; res->u.astructdef.isstruct = (type & 0xf) == T_STRUCT; res->size = aux->u.auxent.x_sym.x_misc.x_lnsz.x_size; } } else { /* No auxents - it's anonymous. */ res->type = coff_structref_type; res->u.astructref.ref = 0; res->size = 0; } break; case T_ENUM: if (aux == NULL) fatal (_("Enum definition needs auxiliary information")); if (aux->fix_tag) { unsigned int idx = INDEXOF (aux->u.auxent.x_sym.x_tagndx.p); /* Referring to a enum defined elsewhere. */ res->type = coff_enumref_type; res->u.aenumref.ref = tindex[idx]; /* PR 17512: file: b85b67e8. */ if (res->u.aenumref.ref) res->size = res->u.aenumref.ref->type->size; else res->size = 0; } else { /* A definition of an enum. */ last_enum = res; res->type = coff_enumdef_type; res->u.aenumdef.elements = empty_scope (); res->size = aux->u.auxent.x_sym.x_misc.x_lnsz.x_size; } break; case T_MOE: break; } for (which_dt = 5; which_dt >= 0; which_dt--) { switch ((type >> ((which_dt * 2) + 4)) & 0x3) { case 0: break; case DT_ARY: { struct coff_type *ptr = ((struct coff_type *) xmalloc (sizeof (struct coff_type))); int els; if (aux == NULL) fatal (_("Array definition needs auxiliary information")); els = (dimind < DIMNUM ? aux->u.auxent.x_sym.x_fcnary.x_ary.x_dimen[dimind] : 0); ++dimind; ptr->type = coff_array_type; /* PR 17512: file: ae1971e2. Check for integer overflow. */ { long long a, z; a = els; z = res->size; a *= z; ptr->size = (int) a; if (ptr->size != a) non_fatal (_("Out of range sum for els (%#x) * size (%#x)"), els, res->size); } ptr->u.array.dim = els; ptr->u.array.array_of = res; res = ptr; break; } case DT_PTR: { struct coff_type *ptr = (struct coff_type *) xmalloc (sizeof (struct coff_type)); ptr->size = PTR_SIZE; ptr->type = coff_pointer_type; ptr->u.pointer.points_to = res; res = ptr; break; } case DT_FCN: { struct coff_type *ptr = (struct coff_type *) xmalloc (sizeof (struct coff_type)); ptr->size = 0; ptr->type = coff_function_type; ptr->u.function.function_returns = res; ptr->u.function.parameters = empty_scope (); ptr->u.function.lines = do_lines (i, N(sym)); ptr->u.function.code = 0; last_function_type = ptr; res = ptr; break; } } } return res; } static struct coff_visible * do_visible (int i) { struct internal_syment *sym = &rawsyms[i].u.syment; struct coff_visible *visible = (struct coff_visible *) (xmalloc (sizeof (struct coff_visible))); enum coff_vis_type t; switch (sym->n_sclass) { case C_MOS: case C_MOU: case C_FIELD: t = coff_vis_member_of_struct; break; case C_MOE: t = coff_vis_member_of_enum; break; case C_REGPARM: t = coff_vis_regparam; break; case C_REG: t = coff_vis_register; break; case C_STRTAG: case C_UNTAG: case C_ENTAG: case C_TPDEF: t = coff_vis_tag; break; case C_AUTOARG: case C_ARG: t = coff_vis_autoparam; break; case C_AUTO: t = coff_vis_auto; break; case C_LABEL: case C_STAT: t = coff_vis_int_def; break; case C_EXT: if (sym->n_scnum == N_UNDEF) { if (sym->n_value) t = coff_vis_common; else t = coff_vis_ext_ref; } else t = coff_vis_ext_def; break; default: fatal (_("Unrecognised symbol class: %d"), sym->n_sclass); break; } visible->type = t; return visible; } /* Define a symbol and attach to block B. */ static int do_define (unsigned int i, struct coff_scope *b) { static int symbol_index; struct internal_syment *sym; struct coff_symbol *s = empty_symbol (); if (b == NULL) fatal (_("ICE: do_define called without a block")); if (i >= rawcount) fatal (_("Out of range symbol index: %u"), i); sym = &rawsyms[i].u.syment; s->number = ++symbol_index; s->name = N(sym); s->sfile = cur_sfile; /* Glue onto the ofile list. */ if (lofile >= 0) { if (ofile->symbol_list_tail) ofile->symbol_list_tail->next_in_ofile_list = s; else ofile->symbol_list_head = s; ofile->symbol_list_tail = s; /* And the block list. */ } if (b->vars_tail) b->vars_tail->next = s; else b->vars_head = s; b->vars_tail = s; b->nvars++; s->type = do_type (i); s->where = do_where (i); s->visible = do_visible (i); tindex[i] = s; /* We remember the lowest address in each section for each source file. */ if (s->where->where == coff_where_memory && s->type->type == coff_secdef_type) { struct coff_isection *is; /* PR 17512: file: 4676c97f. */ if (cur_sfile == NULL) non_fatal (_("Section referenced before any file is defined")); else { is = cur_sfile->section + s->where->section->number; if (!is->init) { is->low = s->where->offset; /* PR 17512: file: 37e7a80d. Check for integer overflow computing low + size. */ { long long a, z; a = s->where->offset; z = s->type->size; a += z; is->high = (int) a; if (a != is->high) non_fatal (_("Out of range sum for offset (%#x) + size (%#x)"), is->low, s->type->size); } /* PR 17512: file: 37e7a80d. */ if (is->high < s->where->offset) fatal (_("Out of range type size: %u"), s->type->size); is->init = 1; is->parent = s->where->section; } } } if (s->type->type == coff_function_type) last_function_symbol = s; return i + sym->n_numaux + 1; } static struct coff_ofile * doit (void) { unsigned int i; bool infile = false; struct coff_ofile *head = (struct coff_ofile *) xmalloc (sizeof (struct coff_ofile)); ofile = head; head->source_head = 0; head->source_tail = 0; head->nsources = 0; head->symbol_list_tail = 0; head->symbol_list_head = 0; do_sections_p1 (head); push_scope (1); for (i = 0; i < rawcount;) { struct internal_syment *sym = &rawsyms[i].u.syment; switch (sym->n_sclass) { case C_FILE: { /* New source file announced. */ struct coff_sfile *n = (struct coff_sfile *) xmalloc (sizeof (struct coff_sfile)); n->section = (struct coff_isection *) xcalloc (sizeof (struct coff_isection), abfd->section_count + 1); cur_sfile = n; n->name = N(sym); n->next = 0; if (infile) pop_scope (); else infile = true; push_scope (1); file_scope = n->scope = top_scope; if (head->source_tail) head->source_tail->next = n; else head->source_head = n; head->source_tail = n; head->nsources++; i += sym->n_numaux + 1; } break; case C_FCN: { char *name = N(sym); if (name[1] == 'b') { /* Function start. */ push_scope (0); /* PR 17512: file: 0ef7fbaf. */ if (last_function_type) last_function_type->u.function.code = top_scope; /* PR 17512: file: 22908266. */ if (sym->n_scnum < ofile->nsections && sym->n_scnum >= 0) top_scope->sec = ofile->sections + sym->n_scnum; else top_scope->sec = NULL; top_scope->offset = sym->n_value; } else { /* PR 17512: file: e92e42e1. */ if (top_scope == NULL) fatal (_("Function start encountered without a top level scope.")); top_scope->size = sym->n_value - top_scope->offset + 1; pop_scope (); } i += sym->n_numaux + 1; } break; case C_BLOCK: { char *name = N(sym); if (name[1] == 'b') { /* Block start. */ push_scope (1); /* PR 17512: file: af7e8e83. */ if (sym->n_scnum < ofile->nsections && sym->n_scnum >= 0) top_scope->sec = ofile->sections + sym->n_scnum; else top_scope->sec = NULL; top_scope->offset = sym->n_value; } else { if (top_scope == NULL) fatal (_("Block start encountered without a scope for it.")); top_scope->size = sym->n_value - top_scope->offset + 1; pop_scope (); } i += sym->n_numaux + 1; } break; case C_REGPARM: case C_ARG: if (last_function_symbol == NULL) fatal (_("Function arguments encountered without a function definition")); i = do_define (i, last_function_symbol->type->u.function.parameters); break; case C_MOS: case C_MOU: case C_FIELD: /* PR 17512: file: 43ab21f4. */ if (last_struct == NULL) fatal (_("Structure element encountered without a structure definition")); i = do_define (i, last_struct->u.astructdef.elements); break; case C_MOE: if (last_enum == NULL) fatal (_("Enum element encountered without an enum definition")); i = do_define (i, last_enum->u.aenumdef.elements); break; case C_STRTAG: case C_ENTAG: case C_UNTAG: /* Various definition. */ if (top_scope == NULL) fatal (_("Aggregate definition encountered without a scope")); i = do_define (i, top_scope); break; case C_EXT: case C_LABEL: if (file_scope == NULL) fatal (_("Label definition encountered without a file scope")); i = do_define (i, file_scope); break; case C_STAT: case C_TPDEF: case C_AUTO: case C_REG: if (top_scope == NULL) fatal (_("Variable definition encountered without a scope")); i = do_define (i, top_scope); break; case C_EOS: i += sym->n_numaux + 1; break; default: fatal (_("Unrecognised symbol class: %d"), sym->n_sclass); } } do_sections_p2 (head); return head; } struct coff_ofile * coff_grok (bfd *inabfd) { long storage; struct coff_ofile *p; abfd = inabfd; if (! bfd_family_coff (abfd)) { non_fatal (_("%s: is not a COFF format file"), bfd_get_filename (abfd)); return NULL; } storage = bfd_get_symtab_upper_bound (abfd); if (storage < 0) bfd_fatal (bfd_get_filename (abfd)); syms = (asymbol **) xmalloc (storage); symcount = bfd_canonicalize_symtab (abfd, syms); if (symcount < 0) bfd_fatal (bfd_get_filename (abfd)); rawsyms = obj_raw_syments (abfd); rawcount = obj_raw_syment_count (abfd); tindex = (struct coff_symbol **) (xcalloc (sizeof (struct coff_symbol *), rawcount)); p = doit (); return p; }