/* ----------------------------------------------------------------------- * * * Copyright 1996-2010 The NASM Authors - All Rights Reserved * See the file AUTHORS included with the NASM distribution for * the specific copyright holders. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following * conditions are met: * * * Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * * Redistributions in binary form must reproduce the above * copyright notice, this list of conditions and the following * disclaimer in the documentation and/or other materials provided * with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND * CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. * * ----------------------------------------------------------------------- */ /* * outcoff.c output routines for the Netwide Assembler to produce * COFF object files (for DJGPP and Win32) */ #include "compiler.h" #include #include #include #include #include #include #include "nasm.h" #include "nasmlib.h" #include "saa.h" #include "raa.h" #include "eval.h" #include "output/outform.h" #include "output/outlib.h" #include "output/pecoff.h" #if defined(OF_COFF) || defined(OF_WIN32) || defined(OF_WIN64) /* * Notes on COFF: * * (0) When I say `standard COFF' below, I mean `COFF as output and * used by DJGPP'. I assume DJGPP gets it right. * * (1) Win32 appears to interpret the term `relative relocation' * differently from standard COFF. Standard COFF understands a * relative relocation to mean that during relocation you add the * address of the symbol you're referencing, and subtract the base * address of the section you're in. Win32 COFF, by contrast, seems * to add the address of the symbol and then subtract the address * of THE BYTE AFTER THE RELOCATED DWORD. Hence the two formats are * subtly incompatible. * * (2) Win32 doesn't bother putting any flags in the header flags * field (at offset 0x12 into the file). * * (3) Win32 uses some extra flags into the section header table: * it defines flags 0x80000000 (writable), 0x40000000 (readable) * and 0x20000000 (executable), and uses them in the expected * combinations. It also defines 0x00100000 through 0x00700000 for * section alignments of 1 through 64 bytes. * * (4) Both standard COFF and Win32 COFF seem to use the DWORD * field directly after the section name in the section header * table for something strange: they store what the address of the * section start point _would_ be, if you laid all the sections end * to end starting at zero. Dunno why. Microsoft's documentation * lists this field as "Virtual Size of Section", which doesn't * seem to fit at all. In fact, Win32 even includes non-linked * sections such as .drectve in this calculation. * * Newer versions of MASM seem to have changed this to be zero, and * that apparently matches the COFF spec, so go with that. * * (5) Standard COFF does something very strange to common * variables: the relocation point for a common variable is as far * _before_ the variable as its size stretches out _after_ it. So * we must fix up common variable references. Win32 seems to be * sensible on this one. */ /* Flag which version of COFF we are currently outputting. */ static bool win32, win64; static int32_t imagebase_sect; #define WRT_IMAGEBASE "..imagebase" struct Reloc { struct Reloc *next; int32_t address; /* relative to _start_ of section */ int32_t symbol; /* symbol number */ enum { SECT_SYMBOLS, ABS_SYMBOL, REAL_SYMBOLS } symbase; /* relocation for symbol number :) */ int16_t type; }; struct Symbol { char name[9]; int32_t strpos; /* string table position of name */ int32_t value; /* address, or COMMON variable size */ int section; /* section number where it's defined * - in COFF codes, not NASM codes */ bool is_global; /* is it a global symbol or not? */ int16_t type; /* 0 - notype, 0x20 - function */ int32_t namlen; /* full name length */ }; static char coff_infile[FILENAME_MAX]; struct Section { struct SAA *data; uint32_t len; int nrelocs; int32_t index; struct Reloc *head, **tail; uint32_t flags; /* section flags */ char *name; int32_t namepos; /* Offset of name into the strings table */ int32_t pos, relpos; }; /* * Some common section flags by default */ #define TEXT_FLAGS_WIN \ (IMAGE_SCN_CNT_CODE | \ IMAGE_SCN_ALIGN_16BYTES | \ IMAGE_SCN_MEM_EXECUTE | \ IMAGE_SCN_MEM_READ) #define TEXT_FLAGS_DOS \ (IMAGE_SCN_CNT_CODE) #define DATA_FLAGS_WIN \ (IMAGE_SCN_CNT_INITIALIZED_DATA | \ IMAGE_SCN_ALIGN_4BYTES | \ IMAGE_SCN_MEM_READ | \ IMAGE_SCN_MEM_WRITE) #define DATA_FLAGS_DOS \ (IMAGE_SCN_CNT_INITIALIZED_DATA) #define BSS_FLAGS_WIN \ (IMAGE_SCN_CNT_UNINITIALIZED_DATA | \ IMAGE_SCN_ALIGN_4BYTES | \ IMAGE_SCN_MEM_READ | \ IMAGE_SCN_MEM_WRITE) #define BSS_FLAGS_DOS \ (IMAGE_SCN_CNT_UNINITIALIZED_DATA) #define RDATA_FLAGS_WIN \ (IMAGE_SCN_CNT_INITIALIZED_DATA | \ IMAGE_SCN_ALIGN_8BYTES | \ IMAGE_SCN_MEM_READ) #define RDATA_FLAGS_DOS \ (IMAGE_SCN_CNT_INITIALIZED_DATA) #define PDATA_FLAGS \ (IMAGE_SCN_CNT_INITIALIZED_DATA | \ IMAGE_SCN_ALIGN_4BYTES | \ IMAGE_SCN_MEM_READ) #define XDATA_FLAGS \ (IMAGE_SCN_CNT_INITIALIZED_DATA | \ IMAGE_SCN_ALIGN_8BYTES | \ IMAGE_SCN_MEM_READ) #define INFO_FLAGS \ (IMAGE_SCN_ALIGN_1BYTES | \ IMAGE_SCN_LNK_INFO | \ IMAGE_SCN_LNK_REMOVE) #define TEXT_FLAGS ((win32 | win64) ? TEXT_FLAGS_WIN : TEXT_FLAGS_DOS) #define DATA_FLAGS ((win32 | win64) ? DATA_FLAGS_WIN : DATA_FLAGS_DOS) #define BSS_FLAGS ((win32 | win64) ? BSS_FLAGS_WIN : BSS_FLAGS_DOS) #define RDATA_FLAGS ((win32 | win64) ? RDATA_FLAGS_WIN : RDATA_FLAGS_DOS) #define SECT_DELTA 32 static struct Section **sects; static int nsects, sectlen; static struct SAA *syms; static uint32_t nsyms; static int32_t def_seg; static int initsym; static struct RAA *bsym, *symval; static struct SAA *strs; static uint32_t strslen; static void coff_gen_init(void); static void coff_sect_write(struct Section *, const uint8_t *, uint32_t); static void coff_write(void); static void coff_section_header(char *, int32_t, int32_t, int32_t, int32_t, int32_t, int, int32_t); static void coff_write_relocs(struct Section *); static void coff_write_symbols(void); static void coff_win32_init(void) { win32 = true; win64 = false; coff_gen_init(); } static void coff_win64_init(void) { maxbits = 64; win32 = false; win64 = true; coff_gen_init(); imagebase_sect = seg_alloc()+1; define_label(WRT_IMAGEBASE, imagebase_sect, 0, NULL, false, false); } static void coff_std_init(void) { win32 = win64 = false; coff_gen_init(); } static void coff_gen_init(void) { sects = NULL; nsects = sectlen = 0; syms = saa_init(sizeof(struct Symbol)); nsyms = 0; bsym = raa_init(); symval = raa_init(); strs = saa_init(1); strslen = 0; def_seg = seg_alloc(); } static void coff_cleanup(int debuginfo) { struct Reloc *r; int i; (void)debuginfo; coff_write(); for (i = 0; i < nsects; i++) { if (sects[i]->data) saa_free(sects[i]->data); while (sects[i]->head) { r = sects[i]->head; sects[i]->head = sects[i]->head->next; nasm_free(r); } nasm_free(sects[i]->name); nasm_free(sects[i]); } nasm_free(sects); saa_free(syms); raa_free(bsym); raa_free(symval); saa_free(strs); } static int coff_make_section(char *name, uint32_t flags) { struct Section *s; size_t namelen; s = nasm_zalloc(sizeof(*s)); if (flags != BSS_FLAGS) s->data = saa_init(1); s->tail = &s->head; if (!strcmp(name, ".text")) s->index = def_seg; else s->index = seg_alloc(); s->namepos = -1; namelen = strlen(name); if (namelen > 8) { if (win32 || win64) { s->namepos = strslen + 4; saa_wbytes(strs, name, namelen + 1); strslen += namelen + 1; } else { namelen = 8; } } s->name = nasm_malloc(namelen + 1); strncpy(s->name, name, namelen); s->name[namelen] = '\0'; s->flags = flags; if (nsects >= sectlen) { sectlen += SECT_DELTA; sects = nasm_realloc(sects, sectlen * sizeof(*sects)); } sects[nsects++] = s; return nsects - 1; } static inline int32_t coff_sectalign_flags(unsigned int align) { return (ilog2_32(align) + 1) << 20; } static int32_t coff_section_names(char *name, int pass, int *bits) { char *p; uint32_t flags, align_and = ~0L, align_or = 0L; int i; /* * Set default bits. */ if (!name) { if(win64) *bits = 64; else *bits = 32; } if (!name) return def_seg; p = name; while (*p && !nasm_isspace(*p)) p++; if (*p) *p++ = '\0'; if (strlen(name) > 8) { if (!win32 && !win64) { nasm_error(ERR_WARNING, "COFF section names limited to 8 characters: truncating"); name[8] = '\0'; } } flags = 0; while (*p && nasm_isspace(*p)) p++; while (*p) { char *q = p; while (*p && !nasm_isspace(*p)) p++; if (*p) *p++ = '\0'; while (*p && nasm_isspace(*p)) p++; if (!nasm_stricmp(q, "code") || !nasm_stricmp(q, "text")) { flags = TEXT_FLAGS; } else if (!nasm_stricmp(q, "data")) { flags = DATA_FLAGS; } else if (!nasm_stricmp(q, "rdata")) { if (win32 | win64) flags = RDATA_FLAGS; else { flags = DATA_FLAGS; /* gotta do something */ nasm_error(ERR_NONFATAL, "standard COFF does not support" " read-only data sections"); } } else if (!nasm_stricmp(q, "bss")) { flags = BSS_FLAGS; } else if (!nasm_stricmp(q, "info")) { if (win32 | win64) flags = INFO_FLAGS; else { flags = DATA_FLAGS; /* gotta do something */ nasm_error(ERR_NONFATAL, "standard COFF does not support" " informational sections"); } } else if (!nasm_strnicmp(q, "align=", 6)) { if (!(win32 | win64)) nasm_error(ERR_NONFATAL, "standard COFF does not support" " section alignment specification"); else { if (q[6 + strspn(q + 6, "0123456789")]) nasm_error(ERR_NONFATAL, "argument to `align' is not numeric"); else { unsigned int align = atoi(q + 6); if (!align || ((align - 1) & align)) nasm_error(ERR_NONFATAL, "argument to `align' is not a" " power of two"); else if (align > 64) nasm_error(ERR_NONFATAL, "Win32 cannot align sections" " to better than 64-byte boundaries"); else { align_and = ~0x00F00000L; align_or = coff_sectalign_flags(align); } } } } } for (i = 0; i < nsects; i++) if (!strcmp(name, sects[i]->name)) break; if (i == nsects) { if (!flags) { if (!strcmp(name, ".data")) flags = DATA_FLAGS; else if (!strcmp(name, ".rdata")) flags = RDATA_FLAGS; else if (!strcmp(name, ".bss")) flags = BSS_FLAGS; else if (win64 && !strcmp(name, ".pdata")) flags = PDATA_FLAGS; else if (win64 && !strcmp(name, ".xdata")) flags = XDATA_FLAGS; else flags = TEXT_FLAGS; } i = coff_make_section(name, flags); if (flags) sects[i]->flags = flags; sects[i]->flags &= align_and; sects[i]->flags |= align_or; } else if (pass == 1) { /* Check if any flags are specified */ if (flags) { unsigned int align_flags = flags & IMAGE_SCN_ALIGN_MASK; /* Warn if non-alignment flags differ */ if ((flags ^ sects[i]->flags) & ~IMAGE_SCN_ALIGN_MASK) { nasm_error(ERR_WARNING, "section attributes ignored on" " redeclaration of section `%s'", name); } /* Check if alignment might be needed */ if (align_flags > IMAGE_SCN_ALIGN_1BYTES) { unsigned int sect_align_flags = sects[i]->flags & IMAGE_SCN_ALIGN_MASK; /* Compute the actual alignment */ unsigned int align = 1u << ((align_flags - IMAGE_SCN_ALIGN_1BYTES) >> 20); /* Update section header as needed */ if (align_flags > sect_align_flags) { sects[i]->flags = (sects[i]->flags & ~IMAGE_SCN_ALIGN_MASK) | align_flags; } /* Check if not already aligned */ if (sects[i]->len % align) { unsigned int padding = (align - sects[i]->len) % align; /* We need to write at most 8095 bytes */ char buffer[8095]; if (sects[i]->flags & IMAGE_SCN_CNT_CODE) { /* Fill with INT 3 instructions */ memset(buffer, 0xCC, padding); } else { memset(buffer, 0x00, padding); } saa_wbytes(sects[i]->data, buffer, padding); sects[i]->len += padding; } } } } return sects[i]->index; } static void coff_deflabel(char *name, int32_t segment, int64_t offset, int is_global, char *special) { int pos = strslen + 4; struct Symbol *sym; if (special) nasm_error(ERR_NONFATAL, "COFF format does not support any" " special symbol types"); if (name[0] == '.' && name[1] == '.' && name[2] != '@') { if (strcmp(name,WRT_IMAGEBASE)) nasm_error(ERR_NONFATAL, "unrecognized special symbol `%s'", name); return; } if (strlen(name) > 8) { size_t nlen = strlen(name)+1; saa_wbytes(strs, name, nlen); strslen += nlen; } else pos = -1; sym = saa_wstruct(syms); sym->strpos = pos; sym->namlen = strlen(name); if (pos == -1) strcpy(sym->name, name); sym->is_global = !!is_global; sym->type = 0; /* Default to T_NULL (no type) */ if (segment == NO_SEG) sym->section = -1; /* absolute symbol */ else { int i; sym->section = 0; for (i = 0; i < nsects; i++) if (segment == sects[i]->index) { sym->section = i + 1; break; } if (!sym->section) sym->is_global = true; } if (is_global == 2) sym->value = offset; else sym->value = (sym->section == 0 ? 0 : offset); /* * define the references from external-symbol segment numbers * to these symbol records. */ if (sym->section == 0) bsym = raa_write(bsym, segment, nsyms); if (segment != NO_SEG) symval = raa_write(symval, segment, sym->section ? 0 : sym->value); nsyms++; } static int32_t coff_add_reloc(struct Section *sect, int32_t segment, int16_t type) { struct Reloc *r; r = *sect->tail = nasm_malloc(sizeof(struct Reloc)); sect->tail = &r->next; r->next = NULL; r->address = sect->len; if (segment == NO_SEG) { r->symbol = 0, r->symbase = ABS_SYMBOL; } else { int i; r->symbase = REAL_SYMBOLS; for (i = 0; i < nsects; i++) { if (segment == sects[i]->index) { r->symbol = i * 2; r->symbase = SECT_SYMBOLS; break; } } if (r->symbase == REAL_SYMBOLS) r->symbol = raa_read(bsym, segment); } r->type = type; sect->nrelocs++; /* * Return the fixup for standard COFF common variables. */ if (r->symbase == REAL_SYMBOLS && !(win32 | win64)) return raa_read(symval, segment); return 0; } static void coff_out(int32_t segto, const void *data, enum out_type type, uint64_t size, int32_t segment, int32_t wrt) { struct Section *s; uint8_t mydata[8], *p; int i; if (wrt != NO_SEG && !win64) { wrt = NO_SEG; /* continue to do _something_ */ nasm_error(ERR_NONFATAL, "WRT not supported by COFF output formats"); } /* * handle absolute-assembly (structure definitions) */ if (segto == NO_SEG) { if (type != OUT_RESERVE) nasm_error(ERR_NONFATAL, "attempt to assemble code in [ABSOLUTE]" " space"); return; } s = NULL; for (i = 0; i < nsects; i++) { if (segto == sects[i]->index) { s = sects[i]; break; } } if (!s) { int tempint; /* ignored */ if (segto != coff_section_names(".text", 2, &tempint)) nasm_error(ERR_PANIC, "strange segment conditions in COFF driver"); else s = sects[nsects - 1]; } /* magically default to 'wrt ..imagebase' in .pdata and .xdata */ if (win64 && wrt == NO_SEG) { if (!strcmp(s->name,".pdata") || !strcmp(s->name,".xdata")) wrt = imagebase_sect; } if (!s->data && type != OUT_RESERVE) { nasm_error(ERR_WARNING, "attempt to initialize memory in" " BSS section `%s': ignored", s->name); s->len += realsize(type, size); return; } if (type == OUT_RESERVE) { if (s->data) { nasm_error(ERR_WARNING, "uninitialised space declared in" " non-BSS section `%s': zeroing", s->name); coff_sect_write(s, NULL, size); } else s->len += size; } else if (type == OUT_RAWDATA) { if (segment != NO_SEG) nasm_error(ERR_PANIC, "OUT_RAWDATA with other than NO_SEG"); coff_sect_write(s, data, size); } else if (type == OUT_ADDRESS) { if (!(win64)) { if (size != 4 && (segment != NO_SEG || wrt != NO_SEG)) { nasm_error(ERR_NONFATAL, "COFF format does not support non-32-bit" " relocations"); } else { int32_t fix = 0; if (segment != NO_SEG || wrt != NO_SEG) { if (wrt != NO_SEG) { nasm_error(ERR_NONFATAL, "COFF format does not support" " WRT types"); } else if (segment % 2) { nasm_error(ERR_NONFATAL, "COFF format does not support" " segment base references"); } else fix = coff_add_reloc(s, segment, IMAGE_REL_I386_DIR32); } p = mydata; WRITELONG(p, *(int64_t *)data + fix); coff_sect_write(s, mydata, size); } } else { int32_t fix = 0; p = mydata; if (size == 8) { if (wrt == imagebase_sect) { nasm_error(ERR_NONFATAL, "operand size mismatch: 'wrt " WRT_IMAGEBASE "' is a 32-bit operand"); } fix = coff_add_reloc(s, segment, IMAGE_REL_AMD64_ADDR64); WRITEDLONG(p, *(int64_t *)data + fix); coff_sect_write(s, mydata, size); } else { fix = coff_add_reloc(s, segment, wrt == imagebase_sect ? IMAGE_REL_AMD64_ADDR32NB: IMAGE_REL_AMD64_ADDR32); WRITELONG(p, *(int64_t *)data + fix); coff_sect_write(s, mydata, size); } } } else if (type == OUT_REL2ADR) { nasm_error(ERR_NONFATAL, "COFF format does not support 16-bit" " relocations"); } else if (type == OUT_REL4ADR) { if (segment == segto && !(win64)) /* Acceptable for RIP-relative */ nasm_error(ERR_PANIC, "intra-segment OUT_REL4ADR"); else if (segment == NO_SEG && win32) nasm_error(ERR_NONFATAL, "Win32 COFF does not correctly support" " relative references to absolute addresses"); else { int32_t fix = 0; if (segment != NO_SEG && segment % 2) { nasm_error(ERR_NONFATAL, "COFF format does not support" " segment base references"); } else fix = coff_add_reloc(s, segment, win64 ? IMAGE_REL_AMD64_REL32 : IMAGE_REL_I386_REL32); p = mydata; if (win32 | win64) { WRITELONG(p, *(int64_t *)data + 4 - size + fix); } else { WRITELONG(p, *(int64_t *)data - (size + s->len) + fix); } coff_sect_write(s, mydata, 4L); } } } static void coff_sect_write(struct Section *sect, const uint8_t *data, uint32_t len) { saa_wbytes(sect->data, data, len); sect->len += len; } typedef struct tagString { struct tagString *next; int len; char *String; } STRING; #define EXPORT_SECTION_NAME ".drectve" #define EXPORT_SECTION_FLAGS INFO_FLAGS /* * #define EXPORT_SECTION_NAME ".text" * #define EXPORT_SECTION_FLAGS TEXT_FLAGS */ static STRING *Exports = NULL; static struct Section *directive_sec; void AddExport(char *name) { STRING *rvp = Exports, *newS; newS = (STRING *) nasm_malloc(sizeof(STRING)); newS->len = strlen(name); newS->next = NULL; newS->String = (char *)nasm_malloc(newS->len + 1); strcpy(newS->String, name); if (rvp == NULL) { int i; for (i = 0; i < nsects; i++) { if (!strcmp(EXPORT_SECTION_NAME, sects[i]->name)) break; } if (i == nsects) i = coff_make_section(EXPORT_SECTION_NAME, EXPORT_SECTION_FLAGS); directive_sec = sects[i]; Exports = newS; } else { while (rvp->next) { if (!strcmp(rvp->String, name)) return; rvp = rvp->next; } rvp->next = newS; } } static void BuildExportTable(STRING **rvp) { STRING *p, *t; if (!rvp || !*rvp) return; list_for_each_safe(p, t, *rvp) { coff_sect_write(directive_sec, (uint8_t *)"-export:", 8); coff_sect_write(directive_sec, (uint8_t *)p->String, p->len); coff_sect_write(directive_sec, (uint8_t *)" ", 1); nasm_free(p->String); nasm_free(p); } *rvp = NULL; } static int coff_directives(enum directives directive, char *value, int pass) { switch (directive) { case D_EXPORT: { char *q, *name; if (pass == 2) return 1; /* ignore in pass two */ name = q = value; while (*q && !nasm_isspace(*q)) q++; if (nasm_isspace(*q)) { *q++ = '\0'; while (*q && nasm_isspace(*q)) q++; } if (!*name) { nasm_error(ERR_NONFATAL, "`export' directive requires export name"); return 1; } if (*q) { nasm_error(ERR_NONFATAL, "unrecognized export qualifier `%s'", q); return 1; } AddExport(name); return 1; } case D_SAFESEH: { static int sxseg=-1; int i; if (!win32) /* Only applicable for -f win32 */ return 0; if (sxseg == -1) { for (i = 0; i < nsects; i++) if (!strcmp(".sxdata",sects[i]->name)) break; if (i == nsects) sxseg = coff_make_section(".sxdata", IMAGE_SCN_LNK_INFO); else sxseg = i; } /* * pass0 == 2 is the only time when the full set of symbols are * guaranteed to be present; it is the final output pass. */ if (pass0 == 2) { uint32_t n; saa_rewind(syms); for (n = 0; n < nsyms; n++) { struct Symbol *sym = saa_rstruct(syms); bool equals; /* * sym->strpos is biased by 4, because symbol * table is prefixed with table length */ if (sym->strpos >=4) { char *name = nasm_malloc(sym->namlen+1); saa_fread(strs, sym->strpos-4, name, sym->namlen); name[sym->namlen] = '\0'; equals = !strcmp(value,name); nasm_free(name); } else { equals = !strcmp(value,sym->name); } if (equals) { /* * this value arithmetics effectively reflects * initsym in coff_write(): 2 for file, 1 for * .absolute and two per each section */ unsigned char value[4],*p=value; WRITELONG(p,n + 2 + 1 + nsects*2); coff_sect_write(sects[sxseg],value,4); sym->type = 0x20; break; } } if (n == nsyms) { nasm_error(ERR_NONFATAL, "`safeseh' directive requires valid symbol"); } } return 1; } default: return 0; } } /* handle relocations storm, valid for win32/64 only */ static inline void coff_adjust_relocs(struct Section *s) { if (s->nrelocs < IMAGE_SCN_MAX_RELOC) return; #ifdef OF_COFF else { if (ofmt == &of_coff) nasm_error(ERR_FATAL, "Too many relocations (%d) for section `%s'", s->nrelocs, s->name); } #endif s->flags |= IMAGE_SCN_LNK_NRELOC_OVFL; s->nrelocs++; } static void coff_write(void) { int32_t pos, sympos, vsize; int i; /* fill in the .drectve section with -export's */ BuildExportTable(&Exports); if (win32) { /* add default value for @feat.00, this allows to 'link /safeseh' */ uint32_t n; saa_rewind(syms); for (n = 0; n < nsyms; n++) { struct Symbol *sym = saa_rstruct(syms); if (sym->strpos == -1 && !strcmp("@feat.00",sym->name)) break; } if (n == nsyms) coff_deflabel("@feat.00", NO_SEG, 1, 0, NULL); } /* * Work out how big the file will get. * Calculate the start of the `real' symbols at the same time. * Check for massive relocations. */ pos = 0x14 + 0x28 * nsects; initsym = 3; /* two for the file, one absolute */ for (i = 0; i < nsects; i++) { if (sects[i]->data) { coff_adjust_relocs(sects[i]); sects[i]->pos = pos; pos += sects[i]->len; sects[i]->relpos = pos; pos += 10 * sects[i]->nrelocs; } else sects[i]->pos = sects[i]->relpos = 0L; initsym += 2; /* two for each section */ } sympos = pos; /* * Output the COFF header. */ if (win64) i = IMAGE_FILE_MACHINE_AMD64; else i = IMAGE_FILE_MACHINE_I386; fwriteint16_t(i, ofile); /* machine type */ fwriteint16_t(nsects, ofile); /* number of sections */ fwriteint32_t(time(NULL), ofile); /* time stamp */ fwriteint32_t(sympos, ofile); fwriteint32_t(nsyms + initsym, ofile); fwriteint16_t(0, ofile); /* no optional header */ /* Flags: 32-bit, no line numbers. Win32 doesn't even bother with them. */ fwriteint16_t((win32 | win64) ? 0 : 0x104, ofile); /* * Output the section headers. */ vsize = 0L; for (i = 0; i < nsects; i++) { coff_section_header(sects[i]->name, sects[i]->namepos, vsize, sects[i]->len, sects[i]->pos, sects[i]->relpos, sects[i]->nrelocs, sects[i]->flags); vsize += sects[i]->len; } /* * Output the sections and their relocations. */ for (i = 0; i < nsects; i++) if (sects[i]->data) { saa_fpwrite(sects[i]->data, ofile); coff_write_relocs(sects[i]); } /* * Output the symbol and string tables. */ coff_write_symbols(); fwriteint32_t(strslen + 4, ofile); /* length includes length count */ saa_fpwrite(strs, ofile); } static void coff_section_header(char *name, int32_t namepos, int32_t vsize, int32_t datalen, int32_t datapos, int32_t relpos, int nrelocs, int32_t flags) { char padname[8]; (void)vsize; if (namepos == -1) { strncpy(padname, name, 8); fwrite(padname, 8, 1, ofile); } else { /* * If name is longer than 8 bytes, write '/' followed * by offset into the strings table represented as * decimal number. */ namepos = namepos % 100000000; padname[0] = '/'; padname[1] = '0' + (namepos / 1000000); namepos = namepos % 1000000; padname[2] = '0' + (namepos / 100000); namepos = namepos % 100000; padname[3] = '0' + (namepos / 10000); namepos = namepos % 10000; padname[4] = '0' + (namepos / 1000); namepos = namepos % 1000; padname[5] = '0' + (namepos / 100); namepos = namepos % 100; padname[6] = '0' + (namepos / 10); namepos = namepos % 10; padname[7] = '0' + (namepos); fwrite(padname, 8, 1, ofile); } fwriteint32_t(0, ofile); /* Virtual size field - set to 0 or vsize */ fwriteint32_t(0L, ofile); /* RVA/offset - we ignore */ fwriteint32_t(datalen, ofile); fwriteint32_t(datapos, ofile); fwriteint32_t(relpos, ofile); fwriteint32_t(0L, ofile); /* no line numbers - we don't do 'em */ /* * a special case -- if there are too many relocs * we have to put IMAGE_SCN_MAX_RELOC here and write * the real relocs number into VirtualAddress of first * relocation */ if (flags & IMAGE_SCN_LNK_NRELOC_OVFL) fwriteint16_t(IMAGE_SCN_MAX_RELOC, ofile); else fwriteint16_t(nrelocs, ofile); fwriteint16_t(0, ofile); /* again, no line numbers */ fwriteint32_t(flags, ofile); } static void coff_write_relocs(struct Section *s) { struct Reloc *r; /* a real number of relocations if needed */ if (s->flags & IMAGE_SCN_LNK_NRELOC_OVFL) { fwriteint32_t(s->nrelocs, ofile); fwriteint32_t(0, ofile); fwriteint16_t(0, ofile); } for (r = s->head; r; r = r->next) { fwriteint32_t(r->address, ofile); fwriteint32_t(r->symbol + (r->symbase == REAL_SYMBOLS ? initsym : r->symbase == ABS_SYMBOL ? initsym - 1 : r->symbase == SECT_SYMBOLS ? 2 : 0), ofile); fwriteint16_t(r->type, ofile); } } static void coff_symbol(char *name, int32_t strpos, int32_t value, int section, int type, int storageclass, int aux) { char padname[8]; if (name) { strncpy(padname, name, 8); fwrite(padname, 8, 1, ofile); } else { fwriteint32_t(0, ofile); fwriteint32_t(strpos, ofile); } fwriteint32_t(value, ofile); fwriteint16_t(section, ofile); fwriteint16_t(type, ofile); fputc(storageclass, ofile); fputc(aux, ofile); } static void coff_write_symbols(void) { char filename[18]; uint32_t i; /* * The `.file' record, and the file name auxiliary record. */ coff_symbol(".file", 0L, 0L, -2, 0, 0x67, 1); strncpy(filename, coff_infile, 18); fwrite(filename, 18, 1, ofile); /* * The section records, with their auxiliaries. */ memset(filename, 0, 18); /* useful zeroed buffer */ for (i = 0; i < (uint32_t) nsects; i++) { coff_symbol(sects[i]->name, 0L, 0L, i + 1, 0, 3, 1); fwriteint32_t(sects[i]->len, ofile); fwriteint16_t(sects[i]->nrelocs,ofile); fwrite(filename, 12, 1, ofile); } /* * The absolute symbol, for relative-to-absolute relocations. */ coff_symbol(".absolut", 0L, 0L, -1, 0, 3, 0); /* * The real symbols. */ saa_rewind(syms); for (i = 0; i < nsyms; i++) { struct Symbol *sym = saa_rstruct(syms); coff_symbol(sym->strpos == -1 ? sym->name : NULL, sym->strpos, sym->value, sym->section, sym->type, sym->is_global ? 2 : 3, 0); } } static void coff_sectalign(int32_t seg, unsigned int value) { struct Section *s = NULL; uint32_t align; int i; for (i = 0; i < nsects; i++) { if (sects[i]->index == seg) { s = sects[i]; break; } } if (!s || !is_power2(value)) return; /* DOS has limitation on 64 bytes */ if (!(win32 | win64) && value > 64) return; align = (s->flags & IMAGE_SCN_ALIGN_MASK); value = coff_sectalign_flags(value); if (value > align) s->flags = (s->flags & ~IMAGE_SCN_ALIGN_MASK) | value; } static int32_t coff_segbase(int32_t segment) { return segment; } static void coff_std_filename(char *inname, char *outname) { strcpy(coff_infile, inname); standard_extension(inname, outname, ".o"); } static void coff_win32_filename(char *inname, char *outname) { strcpy(coff_infile, inname); standard_extension(inname, outname, ".obj"); } extern macros_t coff_stdmac[]; static int coff_set_info(enum geninfo type, char **val) { (void)type; (void)val; return 0; } #endif /* defined(OF_COFF) || defined(OF_WIN32) */ #ifdef OF_COFF struct ofmt of_coff = { "COFF (i386) object files (e.g. DJGPP for DOS)", "coff", 0, null_debug_arr, &null_debug_form, coff_stdmac, coff_std_init, coff_set_info, coff_out, coff_deflabel, coff_section_names, coff_sectalign, coff_segbase, coff_directives, coff_std_filename, coff_cleanup }; #endif #ifdef OF_WIN32 struct ofmt of_win32 = { "Microsoft Win32 (i386) object files", "win32", 0, null_debug_arr, &null_debug_form, coff_stdmac, coff_win32_init, coff_set_info, coff_out, coff_deflabel, coff_section_names, coff_sectalign, coff_segbase, coff_directives, coff_win32_filename, coff_cleanup }; #endif #ifdef OF_WIN64 struct ofmt of_win64 = { "Microsoft Win64 (x86-64) object files", "win64", 0, null_debug_arr, &null_debug_form, coff_stdmac, coff_win64_init, coff_set_info, coff_out, coff_deflabel, coff_section_names, coff_sectalign, coff_segbase, coff_directives, coff_win32_filename, coff_cleanup }; #endif