void
asmbelf(vlong symo)
{
int a, o;
vlong startva, resoff;
ElfEhdr *eh;
ElfPhdr *ph, *pph, *pnote;
ElfShdr *sh;
Section *sect;
eh = getElfEhdr();
switch(thechar) {
default:
diag("unknown architecture in asmbelf");
errorexit();
case '5':
eh->machine = EM_ARM;
break;
case '6':
eh->machine = EM_X86_64;
break;
case '8':
eh->machine = EM_386;
break;
}
startva = INITTEXT - HEADR;
resoff = ELFRESERVE;
pph = nil;
if(isobj) {
/* skip program headers */
eh->phoff = 0;
eh->phentsize = 0;
goto elfobj;
}
/* program header info */
pph = newElfPhdr();
pph->type = PT_PHDR;
pph->flags = PF_R + PF_X;
pph->off = eh->ehsize;
pph->vaddr = INITTEXT - HEADR + pph->off;
pph->paddr = INITTEXT - HEADR + pph->off;
pph->align = INITRND;
/*
* PHDR must be in a loaded segment. Adjust the text
* segment boundaries downwards to include it.
*/
o = segtext.vaddr - pph->vaddr;
segtext.vaddr -= o;
segtext.len += o;
o = segtext.fileoff - pph->off;
segtext.fileoff -= o;
segtext.filelen += o;
if(!debug['d']) {
/* interpreter */
sh = elfshname(".interp");
sh->type = SHT_PROGBITS;
sh->flags = SHF_ALLOC;
sh->addralign = 1;
if(interpreter == nil) {
switch(HEADTYPE) {
case Hlinux:
interpreter = linuxdynld;
break;
case Hfreebsd:
interpreter = freebsddynld;
break;
case Hnetbsd:
interpreter = netbsddynld;
break;
case Hopenbsd:
interpreter = openbsddynld;
break;
}
}
resoff -= elfinterp(sh, startva, resoff, interpreter);
ph = newElfPhdr();
ph->type = PT_INTERP;
ph->flags = PF_R;
phsh(ph, sh);
}
pnote = nil;
if(HEADTYPE == Hnetbsd || HEADTYPE == Hopenbsd) {
sh = nil;
switch(HEADTYPE) {
case Hnetbsd:
sh = elfshname(".note.netbsd.ident");
resoff -= elfnetbsdsig(sh, startva, resoff);
break;
case Hopenbsd:
sh = elfshname(".note.openbsd.ident");
resoff -= elfopenbsdsig(sh, startva, resoff);
break;
}
pnote = newElfPhdr();
pnote->type = PT_NOTE;
pnote->flags = PF_R;
phsh(pnote, sh);
}
if(buildinfolen > 0) {
sh = elfshname(".note.gnu.build-id");
resoff -= elfbuildinfo(sh, startva, resoff);
if(pnote == nil) {
pnote = newElfPhdr();
pnote->type = PT_NOTE;
pnote->flags = PF_R;
}
phsh(pnote, sh);
}
// Additions to the reserved area must be above this line.
USED(resoff);
elfphload(&segtext);
elfphload(&segdata);
/* Dynamic linking sections */
if(!debug['d']) { /* -d suppresses dynamic loader format */
sh = elfshname(".dynsym");
sh->type = SHT_DYNSYM;
sh->flags = SHF_ALLOC;
if(PtrSize == 8)
sh->entsize = ELF64SYMSIZE;
else
sh->entsize = ELF32SYMSIZE;
sh->addralign = PtrSize;
sh->link = elfshname(".dynstr")->shnum;
// sh->info = index of first non-local symbol (number of local symbols)
shsym(sh, lookup(".dynsym", 0));
sh = elfshname(".dynstr");
sh->type = SHT_STRTAB;
sh->flags = SHF_ALLOC;
sh->addralign = 1;
shsym(sh, lookup(".dynstr", 0));
if(elfverneed) {
sh = elfshname(".gnu.version");
sh->type = SHT_GNU_VERSYM;
sh->flags = SHF_ALLOC;
sh->addralign = 2;
sh->link = elfshname(".dynsym")->shnum;
sh->entsize = 2;
shsym(sh, lookup(".gnu.version", 0));
sh = elfshname(".gnu.version_r");
sh->type = SHT_GNU_VERNEED;
sh->flags = SHF_ALLOC;
sh->addralign = PtrSize;
sh->info = elfverneed;
sh->link = elfshname(".dynstr")->shnum;
shsym(sh, lookup(".gnu.version_r", 0));
}
switch(eh->machine) {
case EM_X86_64:
sh = elfshname(".rela.plt");
sh->type = SHT_RELA;
sh->flags = SHF_ALLOC;
sh->entsize = ELF64RELASIZE;
sh->addralign = PtrSize;
sh->link = elfshname(".dynsym")->shnum;
sh->info = elfshname(".plt")->shnum;
shsym(sh, lookup(".rela.plt", 0));
sh = elfshname(".rela");
sh->type = SHT_RELA;
sh->flags = SHF_ALLOC;
sh->entsize = ELF64RELASIZE;
sh->addralign = 8;
sh->link = elfshname(".dynsym")->shnum;
shsym(sh, lookup(".rela", 0));
break;
default:
sh = elfshname(".rel.plt");
sh->type = SHT_REL;
sh->flags = SHF_ALLOC;
sh->entsize = ELF32RELSIZE;
sh->link = elfshname(".dynsym")->shnum;
shsym(sh, lookup(".rel.plt", 0));
sh = elfshname(".rel");
sh->type = SHT_REL;
sh->flags = SHF_ALLOC;
sh->entsize = ELF32RELSIZE;
sh->addralign = 4;
sh->link = elfshname(".dynsym")->shnum;
shsym(sh, lookup(".rel", 0));
break;
}
sh = elfshname(".plt");
sh->type = SHT_PROGBITS;
sh->flags = SHF_ALLOC+SHF_EXECINSTR;
if(eh->machine == EM_X86_64)
sh->entsize = 16;
else
sh->entsize = 4;
sh->addralign = 4;
shsym(sh, lookup(".plt", 0));
sh = elfshname(".got");
sh->type = SHT_PROGBITS;
sh->flags = SHF_ALLOC+SHF_WRITE;
sh->entsize = PtrSize;
sh->addralign = PtrSize;
shsym(sh, lookup(".got", 0));
sh = elfshname(".got.plt");
sh->type = SHT_PROGBITS;
sh->flags = SHF_ALLOC+SHF_WRITE;
sh->entsize = PtrSize;
sh->addralign = PtrSize;
shsym(sh, lookup(".got.plt", 0));
sh = elfshname(".hash");
sh->type = SHT_HASH;
sh->flags = SHF_ALLOC;
sh->entsize = 4;
sh->addralign = PtrSize;
sh->link = elfshname(".dynsym")->shnum;
shsym(sh, lookup(".hash", 0));
/* sh and PT_DYNAMIC for .dynamic section */
sh = elfshname(".dynamic");
sh->type = SHT_DYNAMIC;
sh->flags = SHF_ALLOC+SHF_WRITE;
sh->entsize = 2*PtrSize;
sh->addralign = PtrSize;
sh->link = elfshname(".dynstr")->shnum;
shsym(sh, lookup(".dynamic", 0));
ph = newElfPhdr();
ph->type = PT_DYNAMIC;
ph->flags = PF_R + PF_W;
phsh(ph, sh);
/*
* Thread-local storage segment (really just size).
*/
// Do not emit PT_TLS for OpenBSD since ld.so(1) does
// not currently support it. This is handled
// appropriately in runtime/cgo.
if(tlsoffset != 0 && HEADTYPE != Hopenbsd) {
ph = newElfPhdr();
ph->type = PT_TLS;
ph->flags = PF_R;
ph->memsz = -tlsoffset;
ph->align = PtrSize;
}
}
if(HEADTYPE == Hlinux) {
ph = newElfPhdr();
ph->type = PT_GNU_STACK;
ph->flags = PF_W+PF_R;
ph->align = PtrSize;
ph = newElfPhdr();
ph->type = PT_PAX_FLAGS;
ph->flags = 0x2a00; // mprotect, randexec, emutramp disabled
ph->align = PtrSize;
}
elfobj:
sh = elfshname(".shstrtab");
sh->type = SHT_STRTAB;
sh->addralign = 1;
shsym(sh, lookup(".shstrtab", 0));
eh->shstrndx = sh->shnum;
// put these sections early in the list
if(!debug['s']) {
elfshname(".symtab");
elfshname(".strtab");
}
for(sect=segtext.sect; sect!=nil; sect=sect->next)
elfshbits(sect);
for(sect=segdata.sect; sect!=nil; sect=sect->next)
elfshbits(sect);
if(isobj) {
for(sect=segtext.sect; sect!=nil; sect=sect->next)
elfshreloc(sect);
for(sect=segdata.sect; sect!=nil; sect=sect->next)
elfshreloc(sect);
}
if(!debug['s']) {
sh = elfshname(".symtab");
sh->type = SHT_SYMTAB;
sh->off = symo;
sh->size = symsize;
sh->addralign = PtrSize;
sh->entsize = 8+2*PtrSize;
sh->link = elfshname(".strtab")->shnum;
sh->info = elfglobalsymndx;
sh = elfshname(".strtab");
sh->type = SHT_STRTAB;
sh->off = symo+symsize;
sh->size = elfstrsize;
sh->addralign = 1;
// TODO(rsc): Enable for isobj too, once we know it works.
if(!isobj)
dwarfaddelfheaders();
}
/* Main header */
eh->ident[EI_MAG0] = '\177';
eh->ident[EI_MAG1] = 'E';
eh->ident[EI_MAG2] = 'L';
eh->ident[EI_MAG3] = 'F';
if(HEADTYPE == Hfreebsd)
eh->ident[EI_OSABI] = ELFOSABI_FREEBSD;
else if(HEADTYPE == Hnetbsd)
eh->ident[EI_OSABI] = ELFOSABI_NETBSD;
else if(HEADTYPE == Hopenbsd)
eh->ident[EI_OSABI] = ELFOSABI_OPENBSD;
if(PtrSize == 8)
eh->ident[EI_CLASS] = ELFCLASS64;
else
eh->ident[EI_CLASS] = ELFCLASS32;
eh->ident[EI_DATA] = ELFDATA2LSB;
eh->ident[EI_VERSION] = EV_CURRENT;
if(flag_shared)
eh->type = ET_DYN;
else if(isobj)
eh->type = ET_REL;
else
eh->type = ET_EXEC;
if(!isobj)
eh->entry = entryvalue();
eh->version = EV_CURRENT;
if(pph != nil) {
pph->filesz = eh->phnum * eh->phentsize;
pph->memsz = pph->filesz;
}
cseek(0);
a = 0;
a += elfwritehdr();
a += elfwritephdrs();
a += elfwriteshdrs();
if(!debug['d'])
a += elfwriteinterp();
if(!isobj) {
if(HEADTYPE == Hnetbsd)
a += elfwritenetbsdsig();
if(HEADTYPE == Hopenbsd)
a += elfwriteopenbsdsig();
if(buildinfolen > 0)
a += elfwritebuildinfo();
}
if(a > ELFRESERVE)
diag("ELFRESERVE too small: %d > %d", a, ELFRESERVE);
}
void
asmb(void)
{
int32 v, magic;
int a, dynsym;
uint32 symo, startva, dwarfoff, machlink, resoff;
ElfEhdr *eh;
ElfPhdr *ph, *pph, *pnote;
ElfShdr *sh;
Section *sect;
Sym *sym;
int o;
int i;
if(debug['v'])
Bprint(&bso, "%5.2f asmb\n", cputime());
Bflush(&bso);
sect = segtext.sect;
cseek(sect->vaddr - segtext.vaddr + segtext.fileoff);
codeblk(sect->vaddr, sect->len);
/* output read-only data in text segment (rodata, gosymtab, pclntab, ...) */
for(sect = sect->next; sect != nil; sect = sect->next) {
cseek(sect->vaddr - segtext.vaddr + segtext.fileoff);
datblk(sect->vaddr, sect->len);
}
if(debug['v'])
Bprint(&bso, "%5.2f datblk\n", cputime());
Bflush(&bso);
cseek(segdata.fileoff);
datblk(segdata.vaddr, segdata.filelen);
machlink = 0;
if(HEADTYPE == Hdarwin) {
if(debug['v'])
Bprint(&bso, "%5.2f dwarf\n", cputime());
dwarfoff = rnd(HEADR+segtext.len, INITRND) + rnd(segdata.filelen, INITRND);
cseek(dwarfoff);
segdwarf.fileoff = cpos();
dwarfemitdebugsections();
segdwarf.filelen = cpos() - segdwarf.fileoff;
machlink = domacholink();
}
if(iself) {
/* index of elf text section; needed by asmelfsym, double-checked below */
/* !debug['d'] causes extra sections before the .text section */
elftextsh = 2;
if(!debug['d']) {
elftextsh += 10;
if(elfverneed)
elftextsh += 2;
}
if(HEADTYPE == Hnetbsd || HEADTYPE == Hopenbsd)
elftextsh += 1;
if(buildinfolen > 0)
elftextsh += 1;
}
symsize = 0;
spsize = 0;
lcsize = 0;
symo = 0;
if(!debug['s']) {
// TODO: rationalize
if(debug['v'])
Bprint(&bso, "%5.2f sym\n", cputime());
Bflush(&bso);
switch(HEADTYPE) {
default:
if(iself)
goto Elfsym;
case Hgarbunix:
symo = rnd(HEADR+segtext.filelen, 8192)+segdata.filelen;
break;
case Hunixcoff:
symo = rnd(HEADR+segtext.filelen, INITRND)+segdata.filelen;
break;
case Hplan9x32:
symo = HEADR+segtext.filelen+segdata.filelen;
break;
case Hmsdoscom:
case Hmsdosexe:
debug['s'] = 1;
symo = HEADR+segtext.filelen+segdata.filelen;
break;
case Hdarwin:
symo = rnd(HEADR+segtext.filelen, INITRND)+rnd(segdata.filelen, INITRND)+machlink;
break;
Elfsym:
symo = rnd(HEADR+segtext.filelen, INITRND)+segdata.filelen;
symo = rnd(symo, INITRND);
break;
case Hwindows:
symo = rnd(HEADR+segtext.filelen, PEFILEALIGN)+segdata.filelen;
symo = rnd(symo, PEFILEALIGN);
break;
}
cseek(symo);
switch(HEADTYPE) {
default:
if(iself) {
if(debug['v'])
Bprint(&bso, "%5.2f elfsym\n", cputime());
asmelfsym();
cflush();
cwrite(elfstrdat, elfstrsize);
if(debug['v'])
Bprint(&bso, "%5.2f dwarf\n", cputime());
dwarfemitdebugsections();
}
break;
case Hplan9x32:
asmplan9sym();
cflush();
sym = lookup("pclntab", 0);
if(sym != nil) {
lcsize = sym->np;
for(i=0; i < lcsize; i++)
cput(sym->p[i]);
cflush();
}
break;
case Hwindows:
if(debug['v'])
Bprint(&bso, "%5.2f dwarf\n", cputime());
dwarfemitdebugsections();
break;
}
}
if(debug['v'])
Bprint(&bso, "%5.2f headr\n", cputime());
Bflush(&bso);
cseek(0L);
switch(HEADTYPE) {
default:
if(iself)
goto Elfput;
case Hgarbunix: /* garbage */
lputb(0x160L<<16); /* magic and sections */
lputb(0L); /* time and date */
lputb(rnd(HEADR+segtext.filelen, 4096)+segdata.filelen);
lputb(symsize); /* nsyms */
lputb((0x38L<<16)|7L); /* size of optional hdr and flags */
lputb((0413<<16)|0437L); /* magic and version */
lputb(rnd(HEADR+segtext.filelen, 4096)); /* sizes */
lputb(segdata.filelen);
lputb(segdata.len - segdata.filelen);
lputb(entryvalue()); /* va of entry */
lputb(INITTEXT-HEADR); /* va of base of text */
lputb(segdata.vaddr); /* va of base of data */
lputb(segdata.vaddr+segdata.filelen); /* va of base of bss */
lputb(~0L); /* gp reg mask */
lputb(0L);
lputb(0L);
lputb(0L);
lputb(0L);
lputb(~0L); /* gp value ?? */
break;
case Hunixcoff: /* unix coff */
/*
* file header
*/
lputl(0x0004014c); /* 4 sections, magic */
lputl(0); /* unix time stamp */
lputl(0); /* symbol table */
lputl(0); /* nsyms */
lputl(0x0003001c); /* flags, sizeof a.out header */
/*
* a.out header
*/
lputl(0x10b); /* magic, version stamp */
lputl(rnd(segtext.filelen, INITRND)); /* text sizes */
lputl(segdata.filelen); /* data sizes */
lputl(segdata.len - segdata.filelen); /* bss sizes */
lputb(entryvalue()); /* va of entry */
lputl(INITTEXT); /* text start */
lputl(segdata.vaddr); /* data start */
/*
* text section header
*/
s8put(".text");
lputl(HEADR); /* pa */
lputl(HEADR); /* va */
lputl(segtext.filelen); /* text size */
lputl(HEADR); /* file offset */
lputl(0); /* relocation */
lputl(0); /* line numbers */
lputl(0); /* relocation, line numbers */
lputl(0x20); /* flags text only */
/*
* data section header
*/
s8put(".data");
lputl(segdata.vaddr); /* pa */
lputl(segdata.vaddr); /* va */
lputl(segdata.filelen); /* data size */
lputl(HEADR+segtext.filelen); /* file offset */
lputl(0); /* relocation */
lputl(0); /* line numbers */
lputl(0); /* relocation, line numbers */
lputl(0x40); /* flags data only */
/*
* bss section header
*/
s8put(".bss");
lputl(segdata.vaddr+segdata.filelen); /* pa */
lputl(segdata.vaddr+segdata.filelen); /* va */
lputl(segdata.len - segdata.filelen); /* bss size */
lputl(0); /* file offset */
lputl(0); /* relocation */
lputl(0); /* line numbers */
lputl(0); /* relocation, line numbers */
lputl(0x80); /* flags bss only */
/*
* comment section header
*/
s8put(".comment");
lputl(0); /* pa */
lputl(0); /* va */
lputl(symsize+lcsize); /* comment size */
lputl(HEADR+segtext.filelen+segdata.filelen); /* file offset */
lputl(HEADR+segtext.filelen+segdata.filelen); /* offset of syms */
lputl(HEADR+segtext.filelen+segdata.filelen+symsize);/* offset of line numbers */
lputl(0); /* relocation, line numbers */
lputl(0x200); /* flags comment only */
break;
case Hplan9x32: /* plan9 */
magic = 4*11*11+7;
lputb(magic); /* magic */
lputb(segtext.filelen); /* sizes */
lputb(segdata.filelen);
lputb(segdata.len - segdata.filelen);
lputb(symsize); /* nsyms */
lputb(entryvalue()); /* va of entry */
lputb(spsize); /* sp offsets */
lputb(lcsize); /* line offsets */
break;
case Hmsdoscom:
/* MS-DOS .COM */
break;
case Hmsdosexe:
/* fake MS-DOS .EXE */
v = rnd(HEADR+segtext.filelen, INITRND)+segdata.filelen;
wputl(0x5A4D); /* 'MZ' */
wputl(v % 512); /* bytes in last page */
wputl(rnd(v, 512)/512); /* total number of pages */
wputl(0x0000); /* number of reloc items */
v = rnd(HEADR-(INITTEXT & 0xFFFF), 16);
wputl(v/16); /* size of header */
wputl(0x0000); /* minimum allocation */
wputl(0xFFFF); /* maximum allocation */
wputl(0x0000); /* initial ss value */
wputl(0x0100); /* initial sp value */
wputl(0x0000); /* complemented checksum */
v = entryvalue();
wputl(v); /* initial ip value (!) */
wputl(0x0000); /* initial cs value */
wputl(0x0000);
wputl(0x0000);
wputl(0x003E); /* reloc table offset */
wputl(0x0000); /* overlay number */
break;
case Hdarwin:
asmbmacho();
break;
Elfput:
eh = getElfEhdr();
startva = INITTEXT - HEADR;
resoff = ELFRESERVE;
/* This null SHdr must appear before all others */
newElfShdr(elfstr[ElfStrEmpty]);
/* program header info */
pph = newElfPhdr();
pph->type = PT_PHDR;
pph->flags = PF_R + PF_X;
pph->off = eh->ehsize;
pph->vaddr = INITTEXT - HEADR + pph->off;
pph->paddr = INITTEXT - HEADR + pph->off;
pph->align = INITRND;
/*
* PHDR must be in a loaded segment. Adjust the text
* segment boundaries downwards to include it.
*/
o = segtext.vaddr - pph->vaddr;
segtext.vaddr -= o;
segtext.len += o;
o = segtext.fileoff - pph->off;
segtext.fileoff -= o;
segtext.filelen += o;
if(!debug['d']) {
/* interpreter */
sh = newElfShdr(elfstr[ElfStrInterp]);
sh->type = SHT_PROGBITS;
sh->flags = SHF_ALLOC;
sh->addralign = 1;
if(interpreter == nil) {
switch(HEADTYPE) {
case Hlinux:
interpreter = linuxdynld;
break;
case Hfreebsd:
interpreter = freebsddynld;
break;
case Hnetbsd:
interpreter = netbsddynld;
break;
case Hopenbsd:
interpreter = openbsddynld;
break;
}
}
resoff -= elfinterp(sh, startva, resoff, interpreter);
ph = newElfPhdr();
ph->type = PT_INTERP;
ph->flags = PF_R;
phsh(ph, sh);
}
pnote = nil;
if(HEADTYPE == Hnetbsd || HEADTYPE == Hopenbsd) {
sh = nil;
switch(HEADTYPE) {
case Hnetbsd:
sh = newElfShdr(elfstr[ElfStrNoteNetbsdIdent]);
resoff -= elfnetbsdsig(sh, startva, resoff);
break;
case Hopenbsd:
sh = newElfShdr(elfstr[ElfStrNoteOpenbsdIdent]);
resoff -= elfopenbsdsig(sh, startva, resoff);
break;
}
pnote = newElfPhdr();
pnote->type = PT_NOTE;
pnote->flags = PF_R;
phsh(pnote, sh);
}
if(buildinfolen > 0) {
sh = newElfShdr(elfstr[ElfStrNoteBuildInfo]);
resoff -= elfbuildinfo(sh, startva, resoff);
if(pnote == nil) {
pnote = newElfPhdr();
pnote->type = PT_NOTE;
pnote->flags = PF_R;
}
phsh(pnote, sh);
}
// Additions to the reserved area must be above this line.
USED(resoff);
elfphload(&segtext);
elfphload(&segdata);
/* Dynamic linking sections */
if(!debug['d']) { /* -d suppresses dynamic loader format */
/* S headers for dynamic linking */
sh = newElfShdr(elfstr[ElfStrGot]);
sh->type = SHT_PROGBITS;
sh->flags = SHF_ALLOC+SHF_WRITE;
sh->entsize = 4;
sh->addralign = 4;
shsym(sh, lookup(".got", 0));
sh = newElfShdr(elfstr[ElfStrGotPlt]);
sh->type = SHT_PROGBITS;
sh->flags = SHF_ALLOC+SHF_WRITE;
sh->entsize = 4;
sh->addralign = 4;
shsym(sh, lookup(".got.plt", 0));
dynsym = eh->shnum;
sh = newElfShdr(elfstr[ElfStrDynsym]);
sh->type = SHT_DYNSYM;
sh->flags = SHF_ALLOC;
sh->entsize = ELF32SYMSIZE;
sh->addralign = 4;
sh->link = dynsym+1; // dynstr
// sh->info = index of first non-local symbol (number of local symbols)
shsym(sh, lookup(".dynsym", 0));
sh = newElfShdr(elfstr[ElfStrDynstr]);
sh->type = SHT_STRTAB;
sh->flags = SHF_ALLOC;
sh->addralign = 1;
shsym(sh, lookup(".dynstr", 0));
if(elfverneed) {
sh = newElfShdr(elfstr[ElfStrGnuVersion]);
sh->type = SHT_GNU_VERSYM;
sh->flags = SHF_ALLOC;
sh->addralign = 2;
sh->link = dynsym;
sh->entsize = 2;
shsym(sh, lookup(".gnu.version", 0));
sh = newElfShdr(elfstr[ElfStrGnuVersionR]);
sh->type = SHT_GNU_VERNEED;
sh->flags = SHF_ALLOC;
sh->addralign = 4;
sh->info = elfverneed;
sh->link = dynsym+1; // dynstr
shsym(sh, lookup(".gnu.version_r", 0));
}
sh = newElfShdr(elfstr[ElfStrRelPlt]);
sh->type = SHT_REL;
sh->flags = SHF_ALLOC;
sh->entsize = ELF32RELSIZE;
sh->addralign = 4;
sh->link = dynsym;
sh->info = eh->shnum; // .plt
shsym(sh, lookup(".rel.plt", 0));
sh = newElfShdr(elfstr[ElfStrPlt]);
sh->type = SHT_PROGBITS;
sh->flags = SHF_ALLOC+SHF_EXECINSTR;
sh->entsize = 4;
sh->addralign = 4;
shsym(sh, lookup(".plt", 0));
sh = newElfShdr(elfstr[ElfStrHash]);
sh->type = SHT_HASH;
sh->flags = SHF_ALLOC;
sh->entsize = 4;
sh->addralign = 4;
sh->link = dynsym;
shsym(sh, lookup(".hash", 0));
sh = newElfShdr(elfstr[ElfStrRel]);
sh->type = SHT_REL;
sh->flags = SHF_ALLOC;
sh->entsize = ELF32RELSIZE;
sh->addralign = 4;
sh->link = dynsym;
shsym(sh, lookup(".rel", 0));
/* sh and PT_DYNAMIC for .dynamic section */
sh = newElfShdr(elfstr[ElfStrDynamic]);
sh->type = SHT_DYNAMIC;
sh->flags = SHF_ALLOC+SHF_WRITE;
sh->entsize = 8;
sh->addralign = 4;
sh->link = dynsym+1; // dynstr
shsym(sh, lookup(".dynamic", 0));
ph = newElfPhdr();
ph->type = PT_DYNAMIC;
ph->flags = PF_R + PF_W;
phsh(ph, sh);
/*
* Thread-local storage segment (really just size).
*/
// Do not emit PT_TLS for OpenBSD since ld.so(1) does
// not currently support it. This is handled
// appropriately in runtime/cgo.
if(tlsoffset != 0 && HEADTYPE != Hopenbsd) {
ph = newElfPhdr();
ph->type = PT_TLS;
ph->flags = PF_R;
ph->memsz = -tlsoffset;
ph->align = 4;
}
}
ph = newElfPhdr();
ph->type = PT_GNU_STACK;
ph->flags = PF_W+PF_R;
ph->align = 4;
ph = newElfPhdr();
ph->type = PT_PAX_FLAGS;
ph->flags = 0x2a00; // mprotect, randexec, emutramp disabled
ph->align = 4;
sh = newElfShstrtab(elfstr[ElfStrShstrtab]);
sh->type = SHT_STRTAB;
sh->addralign = 1;
shsym(sh, lookup(".shstrtab", 0));
if(elftextsh != eh->shnum)
diag("elftextsh = %d, want %d", elftextsh, eh->shnum);
for(sect=segtext.sect; sect!=nil; sect=sect->next)
elfshbits(sect);
for(sect=segdata.sect; sect!=nil; sect=sect->next)
elfshbits(sect);
if(!debug['s']) {
sh = newElfShdr(elfstr[ElfStrSymtab]);
sh->type = SHT_SYMTAB;
sh->off = symo;
sh->size = symsize;
sh->addralign = 4;
sh->entsize = 16;
sh->link = eh->shnum; // link to strtab
sh = newElfShdr(elfstr[ElfStrStrtab]);
sh->type = SHT_STRTAB;
sh->off = symo+symsize;
sh->size = elfstrsize;
sh->addralign = 1;
dwarfaddelfheaders();
}
/* Main header */
eh->ident[EI_MAG0] = '\177';
eh->ident[EI_MAG1] = 'E';
eh->ident[EI_MAG2] = 'L';
eh->ident[EI_MAG3] = 'F';
eh->ident[EI_CLASS] = ELFCLASS32;
eh->ident[EI_DATA] = ELFDATA2LSB;
eh->ident[EI_VERSION] = EV_CURRENT;
switch(HEADTYPE) {
case Hfreebsd:
eh->ident[EI_OSABI] = ELFOSABI_FREEBSD;
break;
case Hnetbsd:
eh->ident[EI_OSABI] = ELFOSABI_NETBSD;
break;
case Hopenbsd:
eh->ident[EI_OSABI] = ELFOSABI_OPENBSD;
break;
}
eh->type = ET_EXEC;
eh->machine = EM_386;
eh->version = EV_CURRENT;
eh->entry = entryvalue();
if(pph != nil) {
pph->filesz = eh->phnum * eh->phentsize;
pph->memsz = pph->filesz;
}
cseek(0);
a = 0;
a += elfwritehdr();
a += elfwritephdrs();
a += elfwriteshdrs();
a += elfwriteinterp(elfstr[ElfStrInterp]);
if(HEADTYPE == Hnetbsd)
a += elfwritenetbsdsig(elfstr[ElfStrNoteNetbsdIdent]);
if(HEADTYPE == Hopenbsd)
a += elfwriteopenbsdsig(elfstr[ElfStrNoteOpenbsdIdent]);
if(buildinfolen > 0)
a += elfwritebuildinfo(elfstr[ElfStrNoteBuildInfo]);
if(a > ELFRESERVE)
diag("ELFRESERVE too small: %d > %d", a, ELFRESERVE);
break;
case Hwindows:
asmbpe();
break;
}
cflush();
}
void
asmb(void)
{
int32 t;
int a, dynsym;
uint32 fo, symo, startva;
ElfEhdr *eh;
ElfPhdr *ph, *pph;
ElfShdr *sh;
Section *sect;
if(debug['v'])
Bprint(&bso, "%5.2f asmb\n", cputime());
Bflush(&bso);
sect = segtext.sect;
seek(cout, sect->vaddr - segtext.vaddr + segtext.fileoff, 0);
codeblk(sect->vaddr, sect->len);
/* output read-only data in text segment (rodata, gosymtab and pclntab) */
for(sect = sect->next; sect != nil; sect = sect->next) {
seek(cout, sect->vaddr - segtext.vaddr + segtext.fileoff, 0);
datblk(sect->vaddr, sect->len);
}
if(debug['v'])
Bprint(&bso, "%5.2f datblk\n", cputime());
Bflush(&bso);
seek(cout, segdata.fileoff, 0);
datblk(segdata.vaddr, segdata.filelen);
/* output read-only data in text segment */
sect = segtext.sect->next;
seek(cout, sect->vaddr - segtext.vaddr + segtext.fileoff, 0);
datblk(sect->vaddr, sect->len);
if(iself) {
/* index of elf text section; needed by asmelfsym, double-checked below */
/* !debug['d'] causes extra sections before the .text section */
elftextsh = 1;
if(!debug['d']) {
elftextsh += 10;
if(elfverneed)
elftextsh += 2;
}
}
/* output symbol table */
symsize = 0;
lcsize = 0;
symo = 0;
if(!debug['s']) {
// TODO: rationalize
if(debug['v'])
Bprint(&bso, "%5.2f sym\n", cputime());
Bflush(&bso);
switch(HEADTYPE) {
default:
if(iself)
goto ElfSym;
case Hnoheader:
case Hrisc:
case Hixp1200:
case Hipaq:
debug['s'] = 1;
break;
case Hplan9x32:
symo = HEADR+segtext.len+segdata.filelen;
break;
case Hnetbsd:
symo = rnd(segdata.filelen, 4096);
break;
ElfSym:
symo = rnd(HEADR+segtext.filelen, INITRND)+segdata.filelen;
symo = rnd(symo, INITRND);
break;
}
seek(cout, symo, 0);
if(iself) {
if(debug['v'])
Bprint(&bso, "%5.2f elfsym\n", cputime());
asmelfsym();
cflush();
ewrite(cout, elfstrdat, elfstrsize);
// if(debug['v'])
// Bprint(&bso, "%5.2f dwarf\n", cputime());
// dwarfemitdebugsections();
}
cflush();
}
cursym = nil;
if(debug['v'])
Bprint(&bso, "%5.2f header\n", cputime());
Bflush(&bso);
seek(cout, 0L, 0);
switch(HEADTYPE) {
case Hnoheader: /* no header */
break;
case Hrisc: /* aif for risc os */
lputl(0xe1a00000); /* NOP - decompress code */
lputl(0xe1a00000); /* NOP - relocation code */
lputl(0xeb000000 + 12); /* BL - zero init code */
lputl(0xeb000000 +
(entryvalue()
- INITTEXT
+ HEADR
- 12
- 8) / 4); /* BL - entry code */
lputl(0xef000011); /* SWI - exit code */
lputl(textsize+HEADR); /* text size */
lputl(segdata.filelen); /* data size */
lputl(0); /* sym size */
lputl(segdata.len - segdata.filelen); /* bss size */
lputl(0); /* sym type */
lputl(INITTEXT-HEADR); /* text addr */
lputl(0); /* workspace - ignored */
lputl(32); /* addr mode / data addr flag */
lputl(0); /* data addr */
for(t=0; t<2; t++)
lputl(0); /* reserved */
for(t=0; t<15; t++)
lputl(0xe1a00000); /* NOP - zero init code */
lputl(0xe1a0f00e); /* B (R14) - zero init return */
break;
case Hplan9x32: /* plan 9 */
lput(0x647); /* magic */
lput(textsize); /* sizes */
lput(segdata.filelen);
lput(segdata.len - segdata.filelen);
lput(symsize); /* nsyms */
lput(entryvalue()); /* va of entry */
lput(0L);
lput(lcsize);
break;
case Hnetbsd: /* boot for NetBSD */
lput((143<<16)|0413); /* magic */
lputl(rnd(HEADR+textsize, 4096));
lputl(rnd(segdata.filelen, 4096));
lputl(segdata.len - segdata.filelen);
lputl(symsize); /* nsyms */
lputl(entryvalue()); /* va of entry */
lputl(0L);
lputl(0L);
break;
case Hixp1200: /* boot for IXP1200 */
break;
case Hipaq: /* boot for ipaq */
lputl(0xe3300000); /* nop */
lputl(0xe3300000); /* nop */
lputl(0xe3300000); /* nop */
lputl(0xe3300000); /* nop */
break;
case Hlinux:
/* elf arm */
eh = getElfEhdr();
fo = HEADR;
startva = INITTEXT - fo; /* va of byte 0 of file */
/* This null SHdr must appear before all others */
sh = newElfShdr(elfstr[ElfStrEmpty]);
/* program header info */
pph = newElfPhdr();
pph->type = PT_PHDR;
pph->flags = PF_R + PF_X;
pph->off = eh->ehsize;
pph->vaddr = INITTEXT - HEADR + pph->off;
pph->paddr = INITTEXT - HEADR + pph->off;
pph->align = INITRND;
if(!debug['d']) {
/* interpreter for dynamic linking */
sh = newElfShdr(elfstr[ElfStrInterp]);
sh->type = SHT_PROGBITS;
sh->flags = SHF_ALLOC;
sh->addralign = 1;
if(interpreter == nil)
interpreter = linuxdynld;
elfinterp(sh, startva, interpreter);
ph = newElfPhdr();
ph->type = PT_INTERP;
ph->flags = PF_R;
phsh(ph, sh);
}
elfphload(&segtext);
elfphload(&segdata);
/* Dynamic linking sections */
if (!debug['d']) { /* -d suppresses dynamic loader format */
/* S headers for dynamic linking */
sh = newElfShdr(elfstr[ElfStrGot]);
sh->type = SHT_PROGBITS;
sh->flags = SHF_ALLOC+SHF_WRITE;
sh->entsize = 4;
sh->addralign = 4;
shsym(sh, lookup(".got", 0));
sh = newElfShdr(elfstr[ElfStrGotPlt]);
sh->type = SHT_PROGBITS;
sh->flags = SHF_ALLOC+SHF_WRITE;
sh->entsize = 4;
sh->addralign = 4;
shsym(sh, lookup(".got.plt", 0));
dynsym = eh->shnum;
sh = newElfShdr(elfstr[ElfStrDynsym]);
sh->type = SHT_DYNSYM;
sh->flags = SHF_ALLOC;
sh->entsize = ELF32SYMSIZE;
sh->addralign = 4;
sh->link = dynsym+1; // dynstr
// sh->info = index of first non-local symbol (number of local symbols)
shsym(sh, lookup(".dynsym", 0));
sh = newElfShdr(elfstr[ElfStrDynstr]);
sh->type = SHT_STRTAB;
sh->flags = SHF_ALLOC;
sh->addralign = 1;
shsym(sh, lookup(".dynstr", 0));
sh = newElfShdr(elfstr[ElfStrHash]);
sh->type = SHT_HASH;
sh->flags = SHF_ALLOC;
sh->entsize = 4;
sh->addralign = 4;
sh->link = dynsym;
shsym(sh, lookup(".hash", 0));
sh = newElfShdr(elfstr[ElfStrRel]);
sh->type = SHT_REL;
sh->flags = SHF_ALLOC;
sh->entsize = ELF32RELSIZE;
sh->addralign = 4;
sh->link = dynsym;
shsym(sh, lookup(".rel", 0));
/* sh and PT_DYNAMIC for .dynamic section */
sh = newElfShdr(elfstr[ElfStrDynamic]);
sh->type = SHT_DYNAMIC;
sh->flags = SHF_ALLOC+SHF_WRITE;
sh->entsize = 8;
sh->addralign = 4;
sh->link = dynsym+1; // dynstr
shsym(sh, lookup(".dynamic", 0));
ph = newElfPhdr();
ph->type = PT_DYNAMIC;
ph->flags = PF_R + PF_W;
phsh(ph, sh);
/*
* Thread-local storage segment (really just size).
if(tlsoffset != 0) {
ph = newElfPhdr();
ph->type = PT_TLS;
ph->flags = PF_R;
ph->memsz = -tlsoffset;
ph->align = 4;
}
*/
}
ph = newElfPhdr();
ph->type = PT_GNU_STACK;
ph->flags = PF_W+PF_R;
ph->align = 4;
if(elftextsh != eh->shnum)
diag("elftextsh = %d, want %d", elftextsh, eh->shnum);
for(sect=segtext.sect; sect!=nil; sect=sect->next)
elfshbits(sect);
for(sect=segdata.sect; sect!=nil; sect=sect->next)
elfshbits(sect);
if (!debug['s']) {
sh = newElfShdr(elfstr[ElfStrSymtab]);
sh->type = SHT_SYMTAB;
sh->off = symo;
sh->size = symsize;
sh->addralign = 4;
sh->entsize = 16;
sh->link = eh->shnum; // link to strtab
sh = newElfShdr(elfstr[ElfStrStrtab]);
sh->type = SHT_STRTAB;
sh->off = symo+symsize;
sh->size = elfstrsize;
sh->addralign = 1;
// dwarfaddelfheaders();
}
sh = newElfShstrtab(elfstr[ElfStrShstrtab]);
sh->type = SHT_STRTAB;
sh->addralign = 1;
shsym(sh, lookup(".shstrtab", 0));
/* Main header */
eh->ident[EI_MAG0] = '\177';
eh->ident[EI_MAG1] = 'E';
eh->ident[EI_MAG2] = 'L';
eh->ident[EI_MAG3] = 'F';
eh->ident[EI_CLASS] = ELFCLASS32;
eh->ident[EI_DATA] = ELFDATA2LSB;
eh->ident[EI_VERSION] = EV_CURRENT;
eh->type = ET_EXEC;
eh->machine = EM_ARM;
eh->version = EV_CURRENT;
eh->entry = entryvalue();
if(pph != nil) {
pph->filesz = eh->phnum * eh->phentsize;
pph->memsz = pph->filesz;
}
seek(cout, 0, 0);
a = 0;
a += elfwritehdr();
a += elfwritephdrs();
a += elfwriteshdrs();
cflush();
if(a+elfwriteinterp() > ELFRESERVE)
diag("ELFRESERVE too small: %d > %d", a, ELFRESERVE);
break;
}
cflush();
if(debug['c']){
print("textsize=%d\n", textsize);
print("datsize=%d\n", segdata.filelen);
print("bsssize=%d\n", segdata.len - segdata.filelen);
print("symsize=%d\n", symsize);
print("lcsize=%d\n", lcsize);
print("total=%d\n", textsize+segdata.len+symsize+lcsize);
}
}
void
asmb(void)
{
int32 magic;
int a, dynsym;
vlong vl, startva, symo, dwarfoff, machlink, resoff;
ElfEhdr *eh;
ElfPhdr *ph, *pph;
ElfShdr *sh;
Section *sect;
Sym *sym;
int i, o;
if(debug['v'])
Bprint(&bso, "%5.2f asmb\n", cputime());
Bflush(&bso);
elftextsh = 0;
if(debug['v'])
Bprint(&bso, "%5.2f codeblk\n", cputime());
Bflush(&bso);
sect = segtext.sect;
cseek(sect->vaddr - segtext.vaddr + segtext.fileoff);
codeblk(sect->vaddr, sect->len);
/* output read-only data in text segment (rodata, gosymtab and pclntab) */
for(sect = sect->next; sect != nil; sect = sect->next) {
cseek(sect->vaddr - segtext.vaddr + segtext.fileoff);
datblk(sect->vaddr, sect->len);
}
if(debug['v'])
Bprint(&bso, "%5.2f datblk\n", cputime());
Bflush(&bso);
cseek(segdata.fileoff);
datblk(segdata.vaddr, segdata.filelen);
machlink = 0;
if(HEADTYPE == Hdarwin) {
if(debug['v'])
Bprint(&bso, "%5.2f dwarf\n", cputime());
dwarfoff = rnd(HEADR+segtext.len, INITRND) + rnd(segdata.filelen, INITRND);
cseek(dwarfoff);
segdwarf.fileoff = cpos();
dwarfemitdebugsections();
segdwarf.filelen = cpos() - segdwarf.fileoff;
machlink = domacholink();
}
switch(HEADTYPE) {
default:
diag("unknown header type %d", HEADTYPE);
case Hplan9x32:
case Hplan9x64:
case Helf:
break;
case Hdarwin:
debug['8'] = 1; /* 64-bit addresses */
break;
case Hlinux:
case Hfreebsd:
case Hnetbsd:
case Hopenbsd:
debug['8'] = 1; /* 64-bit addresses */
/* index of elf text section; needed by asmelfsym, double-checked below */
/* !debug['d'] causes extra sections before the .text section */
elftextsh = 2;
if(!debug['d']) {
elftextsh += 10;
if(elfverneed)
elftextsh += 2;
}
if(HEADTYPE == Hnetbsd)
elftextsh += 1;
break;
case Hwindows:
break;
}
symsize = 0;
spsize = 0;
lcsize = 0;
symo = 0;
if(!debug['s']) {
if(debug['v'])
Bprint(&bso, "%5.2f sym\n", cputime());
Bflush(&bso);
switch(HEADTYPE) {
default:
case Hplan9x64:
case Helf:
debug['s'] = 1;
symo = HEADR+segtext.len+segdata.filelen;
break;
case Hdarwin:
symo = rnd(HEADR+segtext.len, INITRND)+rnd(segdata.filelen, INITRND)+machlink;
break;
case Hlinux:
case Hfreebsd:
case Hnetbsd:
case Hopenbsd:
symo = rnd(HEADR+segtext.len, INITRND)+segdata.filelen;
symo = rnd(symo, INITRND);
break;
case Hwindows:
symo = rnd(HEADR+segtext.filelen, PEFILEALIGN)+segdata.filelen;
symo = rnd(symo, PEFILEALIGN);
break;
}
cseek(symo);
switch(HEADTYPE) {
default:
if(iself) {
cseek(symo);
asmelfsym();
cflush();
cwrite(elfstrdat, elfstrsize);
if(debug['v'])
Bprint(&bso, "%5.2f dwarf\n", cputime());
dwarfemitdebugsections();
}
break;
case Hplan9x64:
asmplan9sym();
cflush();
sym = lookup("pclntab", 0);
if(sym != nil) {
lcsize = sym->np;
for(i=0; i < lcsize; i++)
cput(sym->p[i]);
cflush();
}
break;
case Hwindows:
if(debug['v'])
Bprint(&bso, "%5.2f dwarf\n", cputime());
dwarfemitdebugsections();
break;
}
}
if(debug['v'])
Bprint(&bso, "%5.2f headr\n", cputime());
Bflush(&bso);
cseek(0L);
switch(HEADTYPE) {
default:
case Hplan9x64: /* plan9 */
magic = 4*26*26+7;
magic |= 0x00008000; /* fat header */
lputb(magic); /* magic */
lputb(segtext.filelen); /* sizes */
lputb(segdata.filelen);
lputb(segdata.len - segdata.filelen);
lputb(symsize); /* nsyms */
vl = entryvalue();
lputb(PADDR(vl)); /* va of entry */
lputb(spsize); /* sp offsets */
lputb(lcsize); /* line offsets */
vputb(vl); /* va of entry */
break;
case Hplan9x32: /* plan9 */
magic = 4*26*26+7;
lputb(magic); /* magic */
lputb(segtext.filelen); /* sizes */
lputb(segdata.filelen);
lputb(segdata.len - segdata.filelen);
lputb(symsize); /* nsyms */
lputb(entryvalue()); /* va of entry */
lputb(spsize); /* sp offsets */
lputb(lcsize); /* line offsets */
break;
case Hdarwin:
asmbmacho();
break;
case Hlinux:
case Hfreebsd:
case Hnetbsd:
case Hopenbsd:
/* elf amd-64 */
eh = getElfEhdr();
startva = INITTEXT - HEADR;
resoff = ELFRESERVE;
/* This null SHdr must appear before all others */
newElfShdr(elfstr[ElfStrEmpty]);
/* program header info */
pph = newElfPhdr();
pph->type = PT_PHDR;
pph->flags = PF_R + PF_X;
pph->off = eh->ehsize;
pph->vaddr = INITTEXT - HEADR + pph->off;
pph->paddr = INITTEXT - HEADR + pph->off;
pph->align = INITRND;
/*
* PHDR must be in a loaded segment. Adjust the text
* segment boundaries downwards to include it.
*/
o = segtext.vaddr - pph->vaddr;
segtext.vaddr -= o;
segtext.len += o;
o = segtext.fileoff - pph->off;
segtext.fileoff -= o;
segtext.filelen += o;
if(!debug['d']) {
/* interpreter */
sh = newElfShdr(elfstr[ElfStrInterp]);
sh->type = SHT_PROGBITS;
sh->flags = SHF_ALLOC;
sh->addralign = 1;
if(interpreter == nil) {
switch(HEADTYPE) {
case Hlinux:
interpreter = linuxdynld;
break;
case Hfreebsd:
interpreter = freebsddynld;
break;
case Hnetbsd:
interpreter = netbsddynld;
break;
case Hopenbsd:
interpreter = openbsddynld;
break;
}
}
resoff -= elfinterp(sh, startva, resoff, interpreter);
ph = newElfPhdr();
ph->type = PT_INTERP;
ph->flags = PF_R;
phsh(ph, sh);
}
if(HEADTYPE == Hnetbsd) {
sh = newElfShdr(elfstr[ElfStrNoteNetbsdIdent]);
sh->type = SHT_NOTE;
sh->flags = SHF_ALLOC;
sh->addralign = 4;
resoff -= elfnetbsdsig(sh, startva, resoff);
ph = newElfPhdr();
ph->type = PT_NOTE;
ph->flags = PF_R;
phsh(ph, sh);
}
elfphload(&segtext);
elfphload(&segdata);
/* Dynamic linking sections */
if(!debug['d']) { /* -d suppresses dynamic loader format */
/* S headers for dynamic linking */
sh = newElfShdr(elfstr[ElfStrGot]);
sh->type = SHT_PROGBITS;
sh->flags = SHF_ALLOC+SHF_WRITE;
sh->entsize = 8;
sh->addralign = 8;
shsym(sh, lookup(".got", 0));
sh = newElfShdr(elfstr[ElfStrGotPlt]);
sh->type = SHT_PROGBITS;
sh->flags = SHF_ALLOC+SHF_WRITE;
sh->entsize = 8;
sh->addralign = 8;
shsym(sh, lookup(".got.plt", 0));
dynsym = eh->shnum;
sh = newElfShdr(elfstr[ElfStrDynsym]);
sh->type = SHT_DYNSYM;
sh->flags = SHF_ALLOC;
sh->entsize = ELF64SYMSIZE;
sh->addralign = 8;
sh->link = dynsym+1; // dynstr
// sh->info = index of first non-local symbol (number of local symbols)
shsym(sh, lookup(".dynsym", 0));
sh = newElfShdr(elfstr[ElfStrDynstr]);
sh->type = SHT_STRTAB;
sh->flags = SHF_ALLOC;
sh->addralign = 1;
shsym(sh, lookup(".dynstr", 0));
if(elfverneed) {
sh = newElfShdr(elfstr[ElfStrGnuVersion]);
sh->type = SHT_GNU_VERSYM;
sh->flags = SHF_ALLOC;
sh->addralign = 2;
sh->link = dynsym;
sh->entsize = 2;
shsym(sh, lookup(".gnu.version", 0));
sh = newElfShdr(elfstr[ElfStrGnuVersionR]);
sh->type = SHT_GNU_VERNEED;
sh->flags = SHF_ALLOC;
sh->addralign = 8;
sh->info = elfverneed;
sh->link = dynsym+1; // dynstr
shsym(sh, lookup(".gnu.version_r", 0));
}
sh = newElfShdr(elfstr[ElfStrRelaPlt]);
sh->type = SHT_RELA;
sh->flags = SHF_ALLOC;
sh->entsize = ELF64RELASIZE;
sh->addralign = 8;
sh->link = dynsym;
sh->info = eh->shnum; // .plt
shsym(sh, lookup(".rela.plt", 0));
sh = newElfShdr(elfstr[ElfStrPlt]);
sh->type = SHT_PROGBITS;
sh->flags = SHF_ALLOC+SHF_EXECINSTR;
sh->entsize = 16;
sh->addralign = 4;
shsym(sh, lookup(".plt", 0));
sh = newElfShdr(elfstr[ElfStrHash]);
sh->type = SHT_HASH;
sh->flags = SHF_ALLOC;
sh->entsize = 4;
sh->addralign = 8;
sh->link = dynsym;
shsym(sh, lookup(".hash", 0));
sh = newElfShdr(elfstr[ElfStrRela]);
sh->type = SHT_RELA;
sh->flags = SHF_ALLOC;
sh->entsize = ELF64RELASIZE;
sh->addralign = 8;
sh->link = dynsym;
shsym(sh, lookup(".rela", 0));
/* sh and PT_DYNAMIC for .dynamic section */
sh = newElfShdr(elfstr[ElfStrDynamic]);
sh->type = SHT_DYNAMIC;
sh->flags = SHF_ALLOC+SHF_WRITE;
sh->entsize = 16;
sh->addralign = 8;
sh->link = dynsym+1; // dynstr
shsym(sh, lookup(".dynamic", 0));
ph = newElfPhdr();
ph->type = PT_DYNAMIC;
ph->flags = PF_R + PF_W;
phsh(ph, sh);
/*
* Thread-local storage segment (really just size).
*/
if(tlsoffset != 0) {
ph = newElfPhdr();
ph->type = PT_TLS;
ph->flags = PF_R;
ph->memsz = -tlsoffset;
ph->align = 8;
}
}
ph = newElfPhdr();
ph->type = PT_GNU_STACK;
ph->flags = PF_W+PF_R;
ph->align = 8;
ph = newElfPhdr();
ph->type = PT_PAX_FLAGS;
ph->flags = 0x2a00; // mprotect, randexec, emutramp disabled
ph->align = 8;
sh = newElfShstrtab(elfstr[ElfStrShstrtab]);
sh->type = SHT_STRTAB;
sh->addralign = 1;
shsym(sh, lookup(".shstrtab", 0));
if(elftextsh != eh->shnum)
diag("elftextsh = %d, want %d", elftextsh, eh->shnum);
for(sect=segtext.sect; sect!=nil; sect=sect->next)
elfshbits(sect);
for(sect=segdata.sect; sect!=nil; sect=sect->next)
elfshbits(sect);
if(!debug['s']) {
sh = newElfShdr(elfstr[ElfStrSymtab]);
sh->type = SHT_SYMTAB;
sh->off = symo;
sh->size = symsize;
sh->addralign = 8;
sh->entsize = 24;
sh->link = eh->shnum; // link to strtab
sh = newElfShdr(elfstr[ElfStrStrtab]);
sh->type = SHT_STRTAB;
sh->off = symo+symsize;
sh->size = elfstrsize;
sh->addralign = 1;
dwarfaddelfheaders();
}
/* Main header */
eh->ident[EI_MAG0] = '\177';
eh->ident[EI_MAG1] = 'E';
eh->ident[EI_MAG2] = 'L';
eh->ident[EI_MAG3] = 'F';
if(HEADTYPE == Hfreebsd)
eh->ident[EI_OSABI] = ELFOSABI_FREEBSD;
else if(HEADTYPE == Hnetbsd)
eh->ident[EI_OSABI] = ELFOSABI_NETBSD;
else if(HEADTYPE == Hopenbsd)
eh->ident[EI_OSABI] = ELFOSABI_OPENBSD;
eh->ident[EI_CLASS] = ELFCLASS64;
eh->ident[EI_DATA] = ELFDATA2LSB;
eh->ident[EI_VERSION] = EV_CURRENT;
eh->type = ET_EXEC;
eh->machine = EM_X86_64;
eh->version = EV_CURRENT;
eh->entry = entryvalue();
pph->filesz = eh->phnum * eh->phentsize;
pph->memsz = pph->filesz;
cseek(0);
a = 0;
a += elfwritehdr();
a += elfwritephdrs();
a += elfwriteshdrs();
a += elfwriteinterp(elfstr[ElfStrInterp]);
if(HEADTYPE == Hnetbsd)
a += elfwritenetbsdsig(elfstr[ElfStrNoteNetbsdIdent]);
if(a > ELFRESERVE)
diag("ELFRESERVE too small: %d > %d", a, ELFRESERVE);
break;
case Hwindows:
asmbpe();
break;
}
cflush();
}
void
asmb(void)
{
int32 v, magic;
int a, dynsym;
uint32 va, fo, w, symo, startva, machlink;
ElfEhdr *eh;
ElfPhdr *ph, *pph;
ElfShdr *sh;
Section *sect;
Sym *sym;
int i;
if(debug['v'])
Bprint(&bso, "%5.2f asmb\n", cputime());
Bflush(&bso);
sect = segtext.sect;
seek(cout, sect->vaddr - segtext.vaddr + segtext.fileoff, 0);
codeblk(sect->vaddr, sect->len);
/* output read-only data in text segment */
sect = segtext.sect->next;
seek(cout, sect->vaddr - segtext.vaddr + segtext.fileoff, 0);
datblk(sect->vaddr, sect->len);
if(debug['v'])
Bprint(&bso, "%5.2f datblk\n", cputime());
Bflush(&bso);
seek(cout, segdata.fileoff, 0);
datblk(segdata.vaddr, segdata.filelen);
machlink = 0;
if(HEADTYPE == Hdarwin)
machlink = domacholink();
if(iself) {
/* index of elf text section; needed by asmelfsym, double-checked below */
/* !debug['d'] causes extra sections before the .text section */
elftextsh = 1;
if(!debug['d'])
elftextsh += 10;
}
symsize = 0;
spsize = 0;
lcsize = 0;
symo = 0;
if(!debug['s']) {
// TODO: rationalize
if(debug['v'])
Bprint(&bso, "%5.2f sym\n", cputime());
Bflush(&bso);
switch(HEADTYPE) {
default:
if(iself)
goto Elfsym;
case Hgarbunix:
seek(cout, rnd(HEADR+segtext.filelen, 8192)+segdata.filelen, 0);
break;
case Hunixcoff:
seek(cout, rnd(HEADR+segtext.filelen, INITRND)+segdata.filelen, 0);
break;
case Hplan9x32:
symo = HEADR+segtext.filelen+segdata.filelen;
break;
case Hmsdoscom:
case Hmsdosexe:
debug['s'] = 1;
symo = HEADR+segtext.filelen+segdata.filelen;
break;
case Hdarwin:
symo = rnd(HEADR+segtext.filelen, INITRND)+rnd(segdata.filelen, INITRND)+machlink;
break;
Elfsym:
symo = rnd(HEADR+segtext.filelen, INITRND)+segdata.filelen;
symo = rnd(symo, INITRND);
break;
case Hwindows:
// TODO(brainman): not sure what symo meant to be, but it is not used for Windows PE for now anyway
symo = rnd(HEADR+segtext.filelen, PEFILEALIGN)+segdata.filelen;
symo = rnd(symo, PEFILEALIGN);
break;
}
if(!debug['s']) {
seek(cout, symo, 0);
if(HEADTYPE == Hplan9x32) {
asmplan9sym();
cflush();
sym = lookup("pclntab", 0);
if(sym != nil) {
lcsize = sym->np;
for(i=0; i < lcsize; i++)
cput(sym->p[i]);
cflush();
}
} else if(HEADTYPE != Hwindows) {
if(debug['v'])
Bprint(&bso, "%5.2f dwarf\n", cputime());
dwarfemitdebugsections();
}
}
}
if(debug['v'])
Bprint(&bso, "%5.2f headr\n", cputime());
Bflush(&bso);
seek(cout, 0L, 0);
switch(HEADTYPE) {
default:
if(iself)
goto Elfput;
case Hgarbunix: /* garbage */
lputb(0x160L<<16); /* magic and sections */
lputb(0L); /* time and date */
lputb(rnd(HEADR+segtext.filelen, 4096)+segdata.filelen);
lputb(symsize); /* nsyms */
lputb((0x38L<<16)|7L); /* size of optional hdr and flags */
lputb((0413<<16)|0437L); /* magic and version */
lputb(rnd(HEADR+segtext.filelen, 4096)); /* sizes */
lputb(segdata.filelen);
lputb(segdata.len - segdata.filelen);
lputb(entryvalue()); /* va of entry */
lputb(INITTEXT-HEADR); /* va of base of text */
lputb(segdata.vaddr); /* va of base of data */
lputb(segdata.vaddr+segdata.filelen); /* va of base of bss */
lputb(~0L); /* gp reg mask */
lputb(0L);
lputb(0L);
lputb(0L);
lputb(0L);
lputb(~0L); /* gp value ?? */
break;
lputl(0); /* x */
case Hunixcoff: /* unix coff */
/*
* file header
*/
lputl(0x0004014c); /* 4 sections, magic */
lputl(0); /* unix time stamp */
lputl(0); /* symbol table */
lputl(0); /* nsyms */
lputl(0x0003001c); /* flags, sizeof a.out header */
/*
* a.out header
*/
lputl(0x10b); /* magic, version stamp */
lputl(rnd(segtext.filelen, INITRND)); /* text sizes */
lputl(segdata.filelen); /* data sizes */
lputl(segdata.len - segdata.filelen); /* bss sizes */
lputb(entryvalue()); /* va of entry */
lputl(INITTEXT); /* text start */
lputl(segdata.vaddr); /* data start */
/*
* text section header
*/
s8put(".text");
lputl(HEADR); /* pa */
lputl(HEADR); /* va */
lputl(segtext.filelen); /* text size */
lputl(HEADR); /* file offset */
lputl(0); /* relocation */
lputl(0); /* line numbers */
lputl(0); /* relocation, line numbers */
lputl(0x20); /* flags text only */
/*
* data section header
*/
s8put(".data");
lputl(segdata.vaddr); /* pa */
lputl(segdata.vaddr); /* va */
lputl(segdata.filelen); /* data size */
lputl(HEADR+segtext.filelen); /* file offset */
lputl(0); /* relocation */
lputl(0); /* line numbers */
lputl(0); /* relocation, line numbers */
lputl(0x40); /* flags data only */
/*
* bss section header
*/
s8put(".bss");
lputl(segdata.vaddr+segdata.filelen); /* pa */
lputl(segdata.vaddr+segdata.filelen); /* va */
lputl(segdata.len - segdata.filelen); /* bss size */
lputl(0); /* file offset */
lputl(0); /* relocation */
lputl(0); /* line numbers */
lputl(0); /* relocation, line numbers */
lputl(0x80); /* flags bss only */
/*
* comment section header
*/
s8put(".comment");
lputl(0); /* pa */
lputl(0); /* va */
lputl(symsize+lcsize); /* comment size */
lputl(HEADR+segtext.filelen+segdata.filelen); /* file offset */
lputl(HEADR+segtext.filelen+segdata.filelen); /* offset of syms */
lputl(HEADR+segtext.filelen+segdata.filelen+symsize);/* offset of line numbers */
lputl(0); /* relocation, line numbers */
lputl(0x200); /* flags comment only */
break;
case Hplan9x32: /* plan9 */
magic = 4*11*11+7;
lputb(magic); /* magic */
lputb(segtext.filelen); /* sizes */
lputb(segdata.filelen);
lputb(segdata.len - segdata.filelen);
lputb(symsize); /* nsyms */
lputb(entryvalue()); /* va of entry */
lputb(spsize); /* sp offsets */
lputb(lcsize); /* line offsets */
break;
case Hmsdoscom:
/* MS-DOS .COM */
break;
case Hmsdosexe:
/* fake MS-DOS .EXE */
v = rnd(HEADR+segtext.filelen, INITRND)+segdata.filelen;
wputl(0x5A4D); /* 'MZ' */
wputl(v % 512); /* bytes in last page */
wputl(rnd(v, 512)/512); /* total number of pages */
wputl(0x0000); /* number of reloc items */
v = rnd(HEADR-(INITTEXT & 0xFFFF), 16);
wputl(v/16); /* size of header */
wputl(0x0000); /* minimum allocation */
wputl(0xFFFF); /* maximum allocation */
wputl(0x0000); /* initial ss value */
wputl(0x0100); /* initial sp value */
wputl(0x0000); /* complemented checksum */
v = entryvalue();
wputl(v); /* initial ip value (!) */
wputl(0x0000); /* initial cs value */
wputl(0x0000);
wputl(0x0000);
wputl(0x003E); /* reloc table offset */
wputl(0x0000); /* overlay number */
break;
case Hdarwin:
asmbmacho();
break;
Elfput:
/* elf 386 */
if(HEADTYPE == Htiny)
debug['d'] = 1;
eh = getElfEhdr();
fo = HEADR;
startva = INITTEXT - HEADR;
va = startva + fo;
w = segtext.filelen;
/* This null SHdr must appear before all others */
sh = newElfShdr(elfstr[ElfStrEmpty]);
/* program header info */
pph = newElfPhdr();
pph->type = PT_PHDR;
pph->flags = PF_R + PF_X;
pph->off = eh->ehsize;
pph->vaddr = INITTEXT - HEADR + pph->off;
pph->paddr = INITTEXT - HEADR + pph->off;
pph->align = INITRND;
if(!debug['d']) {
/* interpreter */
sh = newElfShdr(elfstr[ElfStrInterp]);
sh->type = SHT_PROGBITS;
sh->flags = SHF_ALLOC;
sh->addralign = 1;
if(interpreter == nil) {
switch(HEADTYPE) {
case Hlinux:
case Hucore:
interpreter = linuxdynld;
break;
case Hfreebsd:
interpreter = freebsddynld;
break;
}
}
elfinterp(sh, startva, interpreter);
ph = newElfPhdr();
ph->type = PT_INTERP;
ph->flags = PF_R;
phsh(ph, sh);
}
elfphload(&segtext);
elfphload(&segdata);
/* Dynamic linking sections */
if (!debug['d']) { /* -d suppresses dynamic loader format */
/* S headers for dynamic linking */
sh = newElfShdr(elfstr[ElfStrGot]);
sh->type = SHT_PROGBITS;
sh->flags = SHF_ALLOC+SHF_WRITE;
sh->entsize = 4;
sh->addralign = 4;
shsym(sh, lookup(".got", 0));
sh = newElfShdr(elfstr[ElfStrGotPlt]);
sh->type = SHT_PROGBITS;
sh->flags = SHF_ALLOC+SHF_WRITE;
sh->entsize = 4;
sh->addralign = 4;
shsym(sh, lookup(".got.plt", 0));
dynsym = eh->shnum;
sh = newElfShdr(elfstr[ElfStrDynsym]);
sh->type = SHT_DYNSYM;
sh->flags = SHF_ALLOC;
sh->entsize = ELF32SYMSIZE;
sh->addralign = 4;
sh->link = dynsym+1; // dynstr
// sh->info = index of first non-local symbol (number of local symbols)
shsym(sh, lookup(".dynsym", 0));
sh = newElfShdr(elfstr[ElfStrDynstr]);
sh->type = SHT_STRTAB;
sh->flags = SHF_ALLOC;
sh->addralign = 1;
shsym(sh, lookup(".dynstr", 0));
sh = newElfShdr(elfstr[ElfStrRelPlt]);
sh->type = SHT_REL;
sh->flags = SHF_ALLOC;
sh->entsize = ELF32RELSIZE;
sh->addralign = 4;
sh->link = dynsym;
sh->info = eh->shnum; // .plt
shsym(sh, lookup(".rel.plt", 0));
sh = newElfShdr(elfstr[ElfStrPlt]);
sh->type = SHT_PROGBITS;
sh->flags = SHF_ALLOC+SHF_EXECINSTR;
sh->entsize = 4;
sh->addralign = 4;
shsym(sh, lookup(".plt", 0));
sh = newElfShdr(elfstr[ElfStrHash]);
sh->type = SHT_HASH;
sh->flags = SHF_ALLOC;
sh->entsize = 4;
sh->addralign = 4;
sh->link = dynsym;
shsym(sh, lookup(".hash", 0));
sh = newElfShdr(elfstr[ElfStrRel]);
sh->type = SHT_REL;
sh->flags = SHF_ALLOC;
sh->entsize = ELF32RELSIZE;
sh->addralign = 4;
sh->link = dynsym;
shsym(sh, lookup(".rel", 0));
/* sh and PT_DYNAMIC for .dynamic section */
sh = newElfShdr(elfstr[ElfStrDynamic]);
sh->type = SHT_DYNAMIC;
sh->flags = SHF_ALLOC+SHF_WRITE;
sh->entsize = 8;
sh->addralign = 4;
sh->link = dynsym+1; // dynstr
shsym(sh, lookup(".dynamic", 0));
ph = newElfPhdr();
ph->type = PT_DYNAMIC;
ph->flags = PF_R + PF_W;
phsh(ph, sh);
/*
* Thread-local storage segment (really just size).
*/
if(tlsoffset != 0) {
ph = newElfPhdr();
ph->type = PT_TLS;
ph->flags = PF_R;
ph->memsz = -tlsoffset;
ph->align = 4;
}
}
ph = newElfPhdr();
ph->type = PT_GNU_STACK;
ph->flags = PF_W+PF_R;
ph->align = 4;
if(elftextsh != eh->shnum)
diag("elftextsh = %d, want %d", elftextsh, eh->shnum);
for(sect=segtext.sect; sect!=nil; sect=sect->next)
elfshbits(sect);
for(sect=segdata.sect; sect!=nil; sect=sect->next)
elfshbits(sect);
if (!debug['s']) {
sh = newElfShdr(elfstr[ElfStrGosymtab]);
sh->type = SHT_PROGBITS;
sh->flags = SHF_ALLOC;
sh->addralign = 1;
shsym(sh, lookup("symtab", 0));
sh = newElfShdr(elfstr[ElfStrGopclntab]);
sh->type = SHT_PROGBITS;
sh->flags = SHF_ALLOC;
sh->addralign = 1;
shsym(sh, lookup("pclntab", 0));
dwarfaddelfheaders();
}
sh = newElfShstrtab(elfstr[ElfStrShstrtab]);
sh->type = SHT_STRTAB;
sh->addralign = 1;
shsym(sh, lookup(".shstrtab", 0));
/* Main header */
eh->ident[EI_MAG0] = '\177';
eh->ident[EI_MAG1] = 'E';
eh->ident[EI_MAG2] = 'L';
eh->ident[EI_MAG3] = 'F';
eh->ident[EI_CLASS] = ELFCLASS32;
eh->ident[EI_DATA] = ELFDATA2LSB;
eh->ident[EI_VERSION] = EV_CURRENT;
switch(HEADTYPE) {
case Hfreebsd:
eh->ident[EI_OSABI] = 9;
break;
}
eh->type = ET_EXEC;
eh->machine = EM_386;
eh->version = EV_CURRENT;
eh->entry = entryvalue();
if(pph != nil) {
pph->filesz = eh->phnum * eh->phentsize;
pph->memsz = pph->filesz;
}
seek(cout, 0, 0);
a = 0;
a += elfwritehdr();
a += elfwritephdrs();
a += elfwriteshdrs();
cflush();
if(a+elfwriteinterp() > ELFRESERVE)
diag("ELFRESERVE too small: %d > %d", a, ELFRESERVE);
break;
case Hwindows:
asmbpe();
break;
}
cflush();
}
