void
cmdmap(Map *map)
{
int i;
char name[MAXSYM];
extern char lastc;
rdc();
readsym(name);
i = findseg(map, name);
if (i < 0) /* not found */
error("Invalid map name");
if (expr(0)) {
if (strcmp(name, "text") == 0)
textseg(expv, &fhdr);
map->seg[i].b = expv;
} else
error("Invalid base address");
if (expr(0))
map->seg[i].e = expv;
else
error("Invalid end address");
if (expr(0))
map->seg[i].f = expv;
else
error("Invalid file offset");
if (rdc()=='?' && map == cormap) {
if (fcor)
close(fcor);
fcor=fsym;
corfil=symfil;
cormap = symmap;
} else if (lastc == '/' && map == symmap) {
if (fsym)
close(fsym);
fsym=fcor;
symfil=corfil;
symmap=cormap;
} else
reread();
}
item(int a)
{ /* name [ . local ] | number | . | ^ | <register | 'x | | */
char *base;
char savc;
uvlong e;
Symbol s;
char gsym[MAXSYM], lsym[MAXSYM];
readchar();
if (isfileref()) {
readfname(gsym);
rdc(); /* skip white space */
if (lastc == ':') { /* it better be */
rdc(); /* skip white space */
if (!getnum(readchar))
error("bad number");
if (expv == 0)
expv = 1; /* file begins at line 1 */
expv = file2pc(gsym, expv);
if (expv == -1)
error("%r");
return 1;
}
error("bad file location");
} else if (symchar(0)) {
readsym(gsym);
if (lastc=='.') {
readchar(); /* ugh */
if (lastc == '.') {
lsym[0] = '.';
readchar();
readsym(lsym+1);
} else if (symchar(0)) {
readsym(lsym);
} else
lsym[0] = 0;
if (localaddr(cormap, gsym, lsym, &e, rget) < 0)
error("%r");
expv = e;
}
else {
if (lookup(0, gsym, &s) == 0)
error("symbol not found");
expv = s.value;
}
reread();
} else if (getnum(readchar)) {
;
} else if (lastc=='.') {
readchar();
if (!symchar(0) && lastc != '.') {
expv = dot;
} else {
if (findsym(rget(cormap, mach->pc), CTEXT, &s) == 0)
error("no current function");
if (lastc == '.') {
lsym[0] = '.';
readchar();
readsym(lsym+1);
} else
readsym(lsym);
if (localaddr(cormap, s.name, lsym, &e, rget) < 0)
error("%r");
expv = e;
}
reread();
} else if (lastc=='"') {
expv=ditto;
} else if (lastc=='+') {
expv=inkdot(dotinc);
} else if (lastc=='^') {
expv=inkdot(-dotinc);
} else if (lastc=='<') {
savc=rdc();
base = regname(savc);
expv = rget(cormap, base);
}
else if (lastc=='\'')
expv = ascval();
else if (a)
error("address expected");
else {
reread();
return(0);
}
return(1);
}
void
ldpe(Biobuf *f, char *pkg, int64 len, char *pn)
{
char *name;
int32 base;
int i, j, l, numaux;
PeObj *obj;
PeSect *sect, *rsect;
IMAGE_SECTION_HEADER sh;
uchar symbuf[18];
Sym *s;
Reloc *r, *rp;
PeSym *sym;
USED(len);
USED(pkg);
if(debug['v'])
Bprint(&bso, "%5.2f ldpe %s\n", cputime(), pn);
sect = nil;
version++;
base = Boffset(f);
obj = mal(sizeof *obj);
obj->f = f;
obj->base = base;
obj->name = pn;
// read header
if(Bread(f, &obj->fh, sizeof obj->fh) != sizeof obj->fh)
goto bad;
// load section list
obj->sect = mal(obj->fh.NumberOfSections*sizeof obj->sect[0]);
obj->nsect = obj->fh.NumberOfSections;
for(i=0; i < obj->fh.NumberOfSections; i++) {
if(Bread(f, &obj->sect[i].sh, sizeof sh) != sizeof sh)
goto bad;
obj->sect[i].size = obj->sect[i].sh.SizeOfRawData;
obj->sect[i].name = (char*)obj->sect[i].sh.Name;
// TODO return error if found .cormeta
}
// load string table
Bseek(f, base+obj->fh.PointerToSymbolTable+18*obj->fh.NumberOfSymbols, 0);
if(Bread(f, &l, sizeof l) != sizeof l)
goto bad;
obj->snames = mal(l);
Bseek(f, base+obj->fh.PointerToSymbolTable+18*obj->fh.NumberOfSymbols, 0);
if(Bread(f, obj->snames, l) != l)
goto bad;
// read symbols
obj->pesym = mal(obj->fh.NumberOfSymbols*sizeof obj->pesym[0]);
obj->npesym = obj->fh.NumberOfSymbols;
Bseek(f, base+obj->fh.PointerToSymbolTable, 0);
for(i=0; i<obj->fh.NumberOfSymbols; i+=numaux+1) {
Bseek(f, base+obj->fh.PointerToSymbolTable+sizeof(symbuf)*i, 0);
if(Bread(f, symbuf, sizeof symbuf) != sizeof symbuf)
goto bad;
if((symbuf[0] == 0) && (symbuf[1] == 0) &&
(symbuf[2] == 0) && (symbuf[3] == 0)) {
l = le32(&symbuf[4]);
obj->pesym[i].name = (char*)&obj->snames[l];
} else { // sym name length <= 8
obj->pesym[i].name = mal(9);
strncpy(obj->pesym[i].name, (char*)symbuf, 8);
obj->pesym[i].name[8] = 0;
}
obj->pesym[i].value = le32(&symbuf[8]);
obj->pesym[i].sectnum = le16(&symbuf[12]);
obj->pesym[i].sclass = symbuf[16];
obj->pesym[i].aux = symbuf[17];
obj->pesym[i].type = le16(&symbuf[14]);
numaux = obj->pesym[i].aux;
if (numaux < 0)
numaux = 0;
}
// create symbols for mapped sections
for(i=0; i<obj->nsect; i++) {
sect = &obj->sect[i];
if(sect->sh.Characteristics&IMAGE_SCN_MEM_DISCARDABLE)
continue;
if(map(obj, sect) < 0)
goto bad;
name = smprint("%s(%s)", pn, sect->name);
s = lookup(name, version);
free(name);
switch(sect->sh.Characteristics&(IMAGE_SCN_CNT_UNINITIALIZED_DATA|IMAGE_SCN_CNT_INITIALIZED_DATA|
IMAGE_SCN_MEM_READ|IMAGE_SCN_MEM_WRITE|IMAGE_SCN_CNT_CODE|IMAGE_SCN_MEM_EXECUTE)) {
case IMAGE_SCN_CNT_INITIALIZED_DATA|IMAGE_SCN_MEM_READ: //.rdata
s->type = SRODATA;
break;
case IMAGE_SCN_CNT_UNINITIALIZED_DATA|IMAGE_SCN_MEM_READ|IMAGE_SCN_MEM_WRITE: //.bss
s->type = SBSS;
break;
case IMAGE_SCN_CNT_INITIALIZED_DATA|IMAGE_SCN_MEM_READ|IMAGE_SCN_MEM_WRITE: //.data
s->type = SDATA;
break;
case IMAGE_SCN_CNT_CODE|IMAGE_SCN_MEM_EXECUTE|IMAGE_SCN_MEM_READ: //.text
s->type = STEXT;
break;
default:
werrstr("unexpected flags for PE section %s", sect->name);
goto bad;
}
s->p = sect->base;
s->np = sect->size;
s->size = sect->size;
if(s->type == STEXT) {
if(etextp)
etextp->next = s;
else
textp = s;
etextp = s;
}
sect->sym = s;
if(strcmp(sect->name, ".rsrc") == 0)
setpersrc(sect->sym);
}
// load relocations
for(i=0; i<obj->nsect; i++) {
rsect = &obj->sect[i];
if(rsect->sym == 0 || rsect->sh.NumberOfRelocations == 0)
continue;
if(rsect->sh.Characteristics&IMAGE_SCN_MEM_DISCARDABLE)
continue;
r = mal(rsect->sh.NumberOfRelocations*sizeof r[0]);
Bseek(f, obj->base+rsect->sh.PointerToRelocations, 0);
for(j=0; j<rsect->sh.NumberOfRelocations; j++) {
rp = &r[j];
if(Bread(f, symbuf, 10) != 10)
goto bad;
uint32 rva, symindex;
uint16 type;
rva = le32(&symbuf[0]);
symindex = le32(&symbuf[4]);
type = le16(&symbuf[8]);
if(readsym(obj, symindex, &sym) < 0)
goto bad;
if(sym->sym == nil) {
werrstr("reloc of invalid sym %s idx=%d type=%d", sym->name, symindex, sym->type);
goto bad;
}
rp->sym = sym->sym;
rp->siz = 4;
rp->off = rva;
switch(type) {
default:
diag("%s: unknown relocation type %d;", pn, type);
case IMAGE_REL_I386_REL32:
case IMAGE_REL_AMD64_REL32:
case IMAGE_REL_AMD64_ADDR32: // R_X86_64_PC32
case IMAGE_REL_AMD64_ADDR32NB:
rp->type = D_PCREL;
rp->add = le32(rsect->base+rp->off);
break;
case IMAGE_REL_I386_DIR32NB:
case IMAGE_REL_I386_DIR32:
rp->type = D_ADDR;
// load addend from image
rp->add = le32(rsect->base+rp->off);
break;
case IMAGE_REL_AMD64_ADDR64: // R_X86_64_64
rp->siz = 8;
rp->type = D_ADDR;
// load addend from image
rp->add = le64(rsect->base+rp->off);
break;
}
}
qsort(r, rsect->sh.NumberOfRelocations, sizeof r[0], rbyoff);
s = rsect->sym;
s->r = r;
s->nr = rsect->sh.NumberOfRelocations;
}
// enter sub-symbols into symbol table.
for(i=0; i<obj->npesym; i++) {
if(obj->pesym[i].name == 0)
continue;
if(obj->pesym[i].name[0] == '.') //skip section
continue;
if(obj->pesym[i].sectnum > 0) {
sect = &obj->sect[obj->pesym[i].sectnum-1];
if(sect->sym == 0)
continue;
}
if(readsym(obj, i, &sym) < 0)
goto bad;
s = sym->sym;
if(sym->sectnum == 0) {// extern
if(s->type == SDYNIMPORT)
s->plt = -2; // flag for dynimport in PE object files.
if (s->type == SXREF && sym->value > 0) {// global data
s->type = SDATA;
s->size = sym->value;
}
continue;
} else if (sym->sectnum > 0) {
sect = &obj->sect[sym->sectnum-1];
if(sect->sym == 0)
diag("%s: %s sym == 0!", pn, s->name);
} else {
diag("%s: %s sectnum < 0!", pn, s->name);
}
if(sect == nil)
return;
s->sub = sect->sym->sub;
sect->sym->sub = s;
s->type = sect->sym->type | SSUB;
s->value = sym->value;
s->size = 4;
s->outer = sect->sym;
if(sect->sym->type == STEXT) {
Prog *p;
if(s->text != P)
diag("%s: duplicate definition of %s", pn, s->name);
// build a TEXT instruction with a unique pc
// just to make the rest of the linker happy.
p = prg();
p->as = ATEXT;
p->from.type = D_EXTERN;
p->from.sym = s;
p->textflag = 7;
p->to.type = D_CONST;
p->link = nil;
p->pc = pc++;
s->text = p;
etextp->next = s;
etextp = s;
}
}
return;
bad:
diag("%s: malformed pe file: %r", pn);
}
void
ldelf(Biobuf *f, char *pkg, int64 len, char *pn)
{
int32 base;
uint64 add, info;
char *name;
int i, j, rela, is64, n, flag;
uchar hdrbuf[64];
uchar *p;
ElfHdrBytes *hdr;
ElfObj *obj;
ElfSect *sect, *rsect;
ElfSym sym;
Endian *e;
Reloc *r, *rp;
LSym *s;
LSym **symbols;
symbols = nil;
if(debug['v'])
Bprint(&bso, "%5.2f ldelf %s\n", cputime(), pn);
ctxt->version++;
base = Boffset(f);
if(Bread(f, hdrbuf, sizeof hdrbuf) != sizeof hdrbuf)
goto bad;
hdr = (ElfHdrBytes*)hdrbuf;
if(memcmp(hdr->ident, ElfMagic, 4) != 0)
goto bad;
switch(hdr->ident[5]) {
case ElfDataLsb:
e = ≤
break;
case ElfDataMsb:
e = &be;
break;
default:
goto bad;
}
// read header
obj = mal(sizeof *obj);
obj->e = e;
obj->f = f;
obj->base = base;
obj->len = len;
obj->name = pn;
is64 = 0;
if(hdr->ident[4] == ElfClass64) {
ElfHdrBytes64* hdr;
is64 = 1;
hdr = (ElfHdrBytes64*)hdrbuf;
obj->type = e->e16(hdr->type);
obj->machine = e->e16(hdr->machine);
obj->version = e->e32(hdr->version);
obj->phoff = e->e64(hdr->phoff);
obj->shoff = e->e64(hdr->shoff);
obj->flags = e->e32(hdr->flags);
obj->ehsize = e->e16(hdr->ehsize);
obj->phentsize = e->e16(hdr->phentsize);
obj->phnum = e->e16(hdr->phnum);
obj->shentsize = e->e16(hdr->shentsize);
obj->shnum = e->e16(hdr->shnum);
obj->shstrndx = e->e16(hdr->shstrndx);
} else {
obj->type = e->e16(hdr->type);
obj->machine = e->e16(hdr->machine);
obj->version = e->e32(hdr->version);
obj->entry = e->e32(hdr->entry);
obj->phoff = e->e32(hdr->phoff);
obj->shoff = e->e32(hdr->shoff);
obj->flags = e->e32(hdr->flags);
obj->ehsize = e->e16(hdr->ehsize);
obj->phentsize = e->e16(hdr->phentsize);
obj->phnum = e->e16(hdr->phnum);
obj->shentsize = e->e16(hdr->shentsize);
obj->shnum = e->e16(hdr->shnum);
obj->shstrndx = e->e16(hdr->shstrndx);
}
obj->is64 = is64;
if(hdr->ident[6] != obj->version)
goto bad;
if(e->e16(hdr->type) != ElfTypeRelocatable) {
diag("%s: elf but not elf relocatable object", pn);
return;
}
switch(thechar) {
default:
diag("%s: elf %s unimplemented", pn, thestring);
return;
case '5':
if(e != &le || obj->machine != ElfMachArm || hdr->ident[4] != ElfClass32) {
diag("%s: elf object but not arm", pn);
return;
}
break;
case '6':
if(e != &le || obj->machine != ElfMachAmd64 || hdr->ident[4] != ElfClass64) {
diag("%s: elf object but not amd64", pn);
return;
}
break;
case '8':
if(e != &le || obj->machine != ElfMach386 || hdr->ident[4] != ElfClass32) {
diag("%s: elf object but not 386", pn);
return;
}
break;
case '9':
if(obj->machine != ElfMachPower64 || hdr->ident[4] != ElfClass64) {
diag("%s: elf object but not ppc64", pn);
return;
}
break;
}
// load section list into memory.
obj->sect = mal(obj->shnum*sizeof obj->sect[0]);
obj->nsect = obj->shnum;
for(i=0; i<obj->nsect; i++) {
if(Bseek(f, base+obj->shoff+i*obj->shentsize, 0) < 0)
goto bad;
sect = &obj->sect[i];
if(is64) {
ElfSectBytes64 b;
werrstr("short read");
if(Bread(f, &b, sizeof b) != sizeof b)
goto bad;
sect->name = (char*)(uintptr)e->e32(b.name);
sect->type = e->e32(b.type);
sect->flags = e->e64(b.flags);
sect->addr = e->e64(b.addr);
sect->off = e->e64(b.off);
sect->size = e->e64(b.size);
sect->link = e->e32(b.link);
sect->info = e->e32(b.info);
sect->align = e->e64(b.align);
sect->entsize = e->e64(b.entsize);
} else {
ElfSectBytes b;
werrstr("short read");
if(Bread(f, &b, sizeof b) != sizeof b)
goto bad;
sect->name = (char*)(uintptr)e->e32(b.name);
sect->type = e->e32(b.type);
sect->flags = e->e32(b.flags);
sect->addr = e->e32(b.addr);
sect->off = e->e32(b.off);
sect->size = e->e32(b.size);
sect->link = e->e32(b.link);
sect->info = e->e32(b.info);
sect->align = e->e32(b.align);
sect->entsize = e->e32(b.entsize);
}
}
// read section string table and translate names
if(obj->shstrndx >= obj->nsect) {
werrstr("shstrndx out of range %d >= %d", obj->shstrndx, obj->nsect);
goto bad;
}
sect = &obj->sect[obj->shstrndx];
if(map(obj, sect) < 0)
goto bad;
for(i=0; i<obj->nsect; i++)
if(obj->sect[i].name != nil)
obj->sect[i].name = (char*)sect->base + (uintptr)obj->sect[i].name;
// load string table for symbols into memory.
obj->symtab = section(obj, ".symtab");
if(obj->symtab == nil) {
// our work is done here - no symbols means nothing can refer to this file
return;
}
if(obj->symtab->link <= 0 || obj->symtab->link >= obj->nsect) {
diag("%s: elf object has symbol table with invalid string table link", pn);
return;
}
obj->symstr = &obj->sect[obj->symtab->link];
if(is64)
obj->nsymtab = obj->symtab->size / sizeof(ElfSymBytes64);
else
obj->nsymtab = obj->symtab->size / sizeof(ElfSymBytes);
if(map(obj, obj->symtab) < 0)
goto bad;
if(map(obj, obj->symstr) < 0)
goto bad;
// load text and data segments into memory.
// they are not as small as the section lists, but we'll need
// the memory anyway for the symbol images, so we might
// as well use one large chunk.
// create symbols for mapped sections
for(i=0; i<obj->nsect; i++) {
sect = &obj->sect[i];
if((sect->type != ElfSectProgbits && sect->type != ElfSectNobits) || !(sect->flags&ElfSectFlagAlloc))
continue;
if(sect->type != ElfSectNobits && map(obj, sect) < 0)
goto bad;
name = smprint("%s(%s)", pkg, sect->name);
s = linklookup(ctxt, name, ctxt->version);
free(name);
switch((int)sect->flags&(ElfSectFlagAlloc|ElfSectFlagWrite|ElfSectFlagExec)) {
default:
werrstr("unexpected flags for ELF section %s", sect->name);
goto bad;
case ElfSectFlagAlloc:
s->type = SRODATA;
break;
case ElfSectFlagAlloc + ElfSectFlagWrite:
if(sect->type == ElfSectNobits)
s->type = SNOPTRBSS;
else
s->type = SNOPTRDATA;
break;
case ElfSectFlagAlloc + ElfSectFlagExec:
s->type = STEXT;
break;
}
if(strcmp(sect->name, ".got") == 0 ||
strcmp(sect->name, ".toc") == 0)
s->type = SELFGOT;
if(sect->type == ElfSectProgbits) {
s->p = sect->base;
s->np = sect->size;
}
s->size = sect->size;
s->align = sect->align;
sect->sym = s;
}
// enter sub-symbols into symbol table.
// symbol 0 is the null symbol.
symbols = malloc(obj->nsymtab * sizeof(symbols[0]));
if(symbols == nil) {
diag("out of memory");
errorexit();
}
for(i=1; i<obj->nsymtab; i++) {
if(readsym(obj, i, &sym, 1) < 0)
goto bad;
symbols[i] = sym.sym;
if(sym.type != ElfSymTypeFunc && sym.type != ElfSymTypeObject && sym.type != ElfSymTypeNone)
continue;
if(sym.shndx == ElfSymShnCommon) {
s = sym.sym;
if(s->size < sym.size)
s->size = sym.size;
if(s->type == 0 || s->type == SXREF)
s->type = SNOPTRBSS;
continue;
}
if(sym.shndx >= obj->nsect || sym.shndx == 0)
continue;
// even when we pass needSym == 1 to readsym, it might still return nil to skip some unwanted symbols
if(sym.sym == S)
continue;
sect = obj->sect+sym.shndx;
if(sect->sym == nil) {
if(strncmp(sym.name, ".Linfo_string", 13) == 0) // clang does this
continue;
diag("%s: sym#%d: ignoring %s in section %d (type %d)", pn, i, sym.name, sym.shndx, sym.type);
continue;
}
s = sym.sym;
if(s->outer != S) {
if(s->dupok)
continue;
diag("%s: duplicate symbol reference: %s in both %s and %s", pn, s->name, s->outer->name, sect->sym->name);
errorexit();
}
s->sub = sect->sym->sub;
sect->sym->sub = s;
s->type = sect->sym->type | (s->type&~SMASK) | SSUB;
if(!(s->cgoexport & CgoExportDynamic))
s->dynimplib = nil; // satisfy dynimport
s->value = sym.value;
s->size = sym.size;
s->outer = sect->sym;
if(sect->sym->type == STEXT) {
if(s->external && !s->dupok)
diag("%s: duplicate definition of %s", pn, s->name);
s->external = 1;
}
if(obj->machine == ElfMachPower64) {
flag = sym.other >> 5;
if(2 <= flag && flag <= 6)
s->localentry = 1 << (flag - 2);
else if(flag == 7)
diag("%s: invalid sym.other 0x%x for %s", pn, sym.other, s->name);
}
}
void
ldelf(Biobuf *f, char *pkg, int64 len, char *pn)
{
int32 base;
uint64 add, info;
char *name;
int i, j, rela, is64, n;
uchar hdrbuf[64];
uchar *p;
ElfHdrBytes *hdr;
ElfObj *obj;
ElfSect *sect, *rsect;
ElfSym sym;
Endian *e;
Reloc *r, *rp;
LSym *s;
LSym **symbols;
symbols = nil;
if(debug['v'])
Bprint(&bso, "%5.2f ldelf %s\n", cputime(), pn);
ctxt->version++;
base = Boffset(f);
if(Bread(f, hdrbuf, sizeof hdrbuf) != sizeof hdrbuf)
goto bad;
hdr = (ElfHdrBytes*)hdrbuf;
if(memcmp(hdr->ident, ElfMagic, 4) != 0)
goto bad;
switch(hdr->ident[5]) {
case ElfDataLsb:
e = ≤
break;
case ElfDataMsb:
e = &be;
break;
default:
goto bad;
}
// read header
obj = mal(sizeof *obj);
obj->e = e;
obj->f = f;
obj->base = base;
obj->len = len;
obj->name = pn;
is64 = 0;
if(hdr->ident[4] == ElfClass64) {
ElfHdrBytes64* hdr;
is64 = 1;
hdr = (ElfHdrBytes64*)hdrbuf;
obj->type = e->e16(hdr->type);
obj->machine = e->e16(hdr->machine);
obj->version = e->e32(hdr->version);
obj->phoff = e->e64(hdr->phoff);
obj->shoff = e->e64(hdr->shoff);
obj->flags = e->e32(hdr->flags);
obj->ehsize = e->e16(hdr->ehsize);
obj->phentsize = e->e16(hdr->phentsize);
obj->phnum = e->e16(hdr->phnum);
obj->shentsize = e->e16(hdr->shentsize);
obj->shnum = e->e16(hdr->shnum);
obj->shstrndx = e->e16(hdr->shstrndx);
} else {
obj->type = e->e16(hdr->type);
obj->machine = e->e16(hdr->machine);
obj->version = e->e32(hdr->version);
obj->entry = e->e32(hdr->entry);
obj->phoff = e->e32(hdr->phoff);
obj->shoff = e->e32(hdr->shoff);
obj->flags = e->e32(hdr->flags);
obj->ehsize = e->e16(hdr->ehsize);
obj->phentsize = e->e16(hdr->phentsize);
obj->phnum = e->e16(hdr->phnum);
obj->shentsize = e->e16(hdr->shentsize);
obj->shnum = e->e16(hdr->shnum);
obj->shstrndx = e->e16(hdr->shstrndx);
}
obj->is64 = is64;
if(hdr->ident[6] != obj->version)
goto bad;
if(e->e16(hdr->type) != ElfTypeRelocatable) {
diag("%s: elf but not elf relocatable object", pn);
return;
}
switch(thechar) {
default:
diag("%s: elf %s unimplemented", pn, thestring);
return;
case '5':
if(e != &le || obj->machine != ElfMachArm || hdr->ident[4] != ElfClass32) {
diag("%s: elf object but not arm", pn);
return;
}
break;
case '6':
if(e != &le || obj->machine != ElfMachAmd64 || hdr->ident[4] != ElfClass64) {
diag("%s: elf object but not amd64", pn);
return;
}
break;
case '8':
if(e != &le || obj->machine != ElfMach386 || hdr->ident[4] != ElfClass32) {
diag("%s: elf object but not 386", pn);
return;
}
break;
}
// load section list into memory.
obj->sect = mal(obj->shnum*sizeof obj->sect[0]);
obj->nsect = obj->shnum;
for(i=0; i<obj->nsect; i++) {
if(Bseek(f, base+obj->shoff+i*obj->shentsize, 0) < 0)
goto bad;
sect = &obj->sect[i];
if(is64) {
ElfSectBytes64 b;
werrstr("short read");
if(Bread(f, &b, sizeof b) != sizeof b)
goto bad;
sect->name = (char*)(uintptr)e->e32(b.name);
sect->type = e->e32(b.type);
sect->flags = e->e64(b.flags);
sect->addr = e->e64(b.addr);
sect->off = e->e64(b.off);
sect->size = e->e64(b.size);
sect->link = e->e32(b.link);
sect->info = e->e32(b.info);
sect->align = e->e64(b.align);
sect->entsize = e->e64(b.entsize);
} else {
ElfSectBytes b;
werrstr("short read");
if(Bread(f, &b, sizeof b) != sizeof b)
goto bad;
sect->name = (char*)(uintptr)e->e32(b.name);
sect->type = e->e32(b.type);
sect->flags = e->e32(b.flags);
sect->addr = e->e32(b.addr);
sect->off = e->e32(b.off);
sect->size = e->e32(b.size);
sect->link = e->e32(b.link);
sect->info = e->e32(b.info);
sect->align = e->e32(b.align);
sect->entsize = e->e32(b.entsize);
}
}
// read section string table and translate names
if(obj->shstrndx >= obj->nsect) {
werrstr("shstrndx out of range %d >= %d", obj->shstrndx, obj->nsect);
goto bad;
}
sect = &obj->sect[obj->shstrndx];
if(map(obj, sect) < 0)
goto bad;
for(i=0; i<obj->nsect; i++)
if(obj->sect[i].name != nil)
obj->sect[i].name = (char*)sect->base + (uintptr)obj->sect[i].name;
// load string table for symbols into memory.
obj->symtab = section(obj, ".symtab");
if(obj->symtab == nil) {
// our work is done here - no symbols means nothing can refer to this file
return;
}
if(obj->symtab->link <= 0 || obj->symtab->link >= obj->nsect) {
diag("%s: elf object has symbol table with invalid string table link", pn);
return;
}
obj->symstr = &obj->sect[obj->symtab->link];
if(is64)
obj->nsymtab = obj->symtab->size / sizeof(ElfSymBytes64);
else
obj->nsymtab = obj->symtab->size / sizeof(ElfSymBytes);
if(map(obj, obj->symtab) < 0)
goto bad;
if(map(obj, obj->symstr) < 0)
goto bad;
// load text and data segments into memory.
// they are not as small as the section lists, but we'll need
// the memory anyway for the symbol images, so we might
// as well use one large chunk.
// create symbols for mapped sections
for(i=0; i<obj->nsect; i++) {
sect = &obj->sect[i];
if((sect->type != ElfSectProgbits && sect->type != ElfSectNobits) || !(sect->flags&ElfSectFlagAlloc))
continue;
if(sect->type != ElfSectNobits && map(obj, sect) < 0)
goto bad;
name = smprint("%s(%s)", pkg, sect->name);
s = linklookup(ctxt, name, ctxt->version);
free(name);
switch((int)sect->flags&(ElfSectFlagAlloc|ElfSectFlagWrite|ElfSectFlagExec)) {
default:
werrstr("unexpected flags for ELF section %s", sect->name);
goto bad;
case ElfSectFlagAlloc:
s->type = SRODATA;
break;
case ElfSectFlagAlloc + ElfSectFlagWrite:
s->type = SNOPTRDATA;
break;
case ElfSectFlagAlloc + ElfSectFlagExec:
s->type = STEXT;
break;
}
if(sect->type == ElfSectProgbits) {
s->p = sect->base;
s->np = sect->size;
}
s->size = sect->size;
s->align = sect->align;
sect->sym = s;
}
// enter sub-symbols into symbol table.
// symbol 0 is the null symbol.
symbols = malloc(obj->nsymtab * sizeof(symbols[0]));
if(symbols == nil) {
diag("out of memory");
errorexit();
}
for(i=1; i<obj->nsymtab; i++) {
if(readsym(obj, i, &sym, 1) < 0)
goto bad;
symbols[i] = sym.sym;
if(sym.type != ElfSymTypeFunc && sym.type != ElfSymTypeObject && sym.type != ElfSymTypeNone)
continue;
if(sym.shndx == ElfSymShnCommon) {
s = sym.sym;
if(s->size < sym.size)
s->size = sym.size;
if(s->type == 0 || s->type == SXREF)
s->type = SNOPTRBSS;
continue;
}
if(sym.shndx >= obj->nsect || sym.shndx == 0)
continue;
// even when we pass needSym == 1 to readsym, it might still return nil to skip some unwanted symbols
if(sym.sym == S)
continue;
sect = obj->sect+sym.shndx;
if(sect->sym == nil) {
if(strncmp(sym.name, ".Linfo_string", 13) == 0) // clang does this
continue;
diag("%s: sym#%d: ignoring %s in section %d (type %d)", pn, i, sym.name, sym.shndx, sym.type);
continue;
}
s = sym.sym;
if(s->outer != S) {
if(s->dupok)
continue;
diag("%s: duplicate symbol reference: %s in both %s and %s", pn, s->name, s->outer->name, sect->sym->name);
errorexit();
}
s->sub = sect->sym->sub;
sect->sym->sub = s;
s->type = sect->sym->type | (s->type&~SMASK) | SSUB;
if(!(s->cgoexport & CgoExportDynamic))
s->dynimplib = nil; // satisfy dynimport
s->value = sym.value;
s->size = sym.size;
s->outer = sect->sym;
if(sect->sym->type == STEXT) {
if(s->external && !s->dupok)
diag("%s: duplicate definition of %s", pn, s->name);
s->external = 1;
}
}
// Sort outer lists by address, adding to textp.
// This keeps textp in increasing address order.
for(i=0; i<obj->nsect; i++) {
s = obj->sect[i].sym;
if(s == S)
continue;
if(s->sub)
s->sub = listsort(s->sub, valuecmp, offsetof(LSym, sub));
if(s->type == STEXT) {
if(s->onlist)
sysfatal("symbol %s listed multiple times", s->name);
s->onlist = 1;
if(ctxt->etextp)
ctxt->etextp->next = s;
else
ctxt->textp = s;
ctxt->etextp = s;
for(s = s->sub; s != S; s = s->sub) {
if(s->onlist)
sysfatal("symbol %s listed multiple times", s->name);
s->onlist = 1;
ctxt->etextp->next = s;
ctxt->etextp = s;
}
}
}
// load relocations
for(i=0; i<obj->nsect; i++) {
rsect = &obj->sect[i];
if(rsect->type != ElfSectRela && rsect->type != ElfSectRel)
continue;
if(rsect->info >= obj->nsect || obj->sect[rsect->info].base == nil)
continue;
sect = &obj->sect[rsect->info];
if(map(obj, rsect) < 0)
goto bad;
rela = rsect->type == ElfSectRela;
n = rsect->size/(4+4*is64)/(2+rela);
r = mal(n*sizeof r[0]);
p = rsect->base;
for(j=0; j<n; j++) {
add = 0;
rp = &r[j];
if(is64) {
// 64-bit rel/rela
rp->off = e->e64(p);
p += 8;
info = e->e64(p);
p += 8;
if(rela) {
add = e->e64(p);
p += 8;
}
} else {
// 32-bit rel/rela
rp->off = e->e32(p);
p += 4;
info = e->e32(p);
info = info>>8<<32 | (info&0xff); // convert to 64-bit info
p += 4;
if(rela) {
add = e->e32(p);
p += 4;
}
}
if((info & 0xffffffff) == 0) { // skip R_*_NONE relocation
j--;
n--;
continue;
}
if((info >> 32) == 0) { // absolute relocation, don't bother reading the null symbol
rp->sym = S;
} else {
if(readsym(obj, info>>32, &sym, 0) < 0)
goto bad;
sym.sym = symbols[info>>32];
if(sym.sym == nil) {
werrstr("%s#%d: reloc of invalid sym #%d %s shndx=%d type=%d",
sect->sym->name, j, (int)(info>>32), sym.name, sym.shndx, sym.type);
goto bad;
}
rp->sym = sym.sym;
}
rp->type = reltype(pn, (uint32)info, &rp->siz);
if(rela)
rp->add = add;
else {
// load addend from image
if(rp->siz == 4)
rp->add = e->e32(sect->base+rp->off);
else if(rp->siz == 8)
rp->add = e->e64(sect->base+rp->off);
else
diag("invalid rela size %d", rp->siz);
}
if(rp->siz == 4)
rp->add = (int32)rp->add;
//print("rel %s %d %d %s %#llx\n", sect->sym->name, rp->type, rp->siz, rp->sym->name, rp->add);
}
void
ldpe(Biobuf *f, char *pkg, int64 len, char *pn)
{
char *name;
int32 base;
uint32 l;
int i, j, numaux;
PeObj *obj;
PeSect *sect, *rsect;
IMAGE_SECTION_HEADER sh;
uchar symbuf[18];
LSym *s;
Reloc *r, *rp;
PeSym *sym;
USED(len);
if(debug['v'])
Bprint(&bso, "%5.2f ldpe %s\n", cputime(), pn);
sect = nil;
ctxt->version++;
base = Boffset(f);
obj = mal(sizeof *obj);
obj->f = f;
obj->base = base;
obj->name = pn;
// read header
if(Bread(f, &obj->fh, sizeof obj->fh) != sizeof obj->fh)
goto bad;
// load section list
obj->sect = mal(obj->fh.NumberOfSections*sizeof obj->sect[0]);
obj->nsect = obj->fh.NumberOfSections;
for(i=0; i < obj->fh.NumberOfSections; i++) {
if(Bread(f, &obj->sect[i].sh, sizeof sh) != sizeof sh)
goto bad;
obj->sect[i].size = obj->sect[i].sh.SizeOfRawData;
obj->sect[i].name = (char*)obj->sect[i].sh.Name;
// TODO return error if found .cormeta
}
// load string table
Bseek(f, base+obj->fh.PointerToSymbolTable+sizeof(symbuf)*obj->fh.NumberOfSymbols, 0);
if(Bread(f, symbuf, 4) != 4)
goto bad;
l = le32(symbuf);
obj->snames = mal(l);
Bseek(f, base+obj->fh.PointerToSymbolTable+sizeof(symbuf)*obj->fh.NumberOfSymbols, 0);
if(Bread(f, obj->snames, l) != l)
goto bad;
// read symbols
obj->pesym = mal(obj->fh.NumberOfSymbols*sizeof obj->pesym[0]);
obj->npesym = obj->fh.NumberOfSymbols;
Bseek(f, base+obj->fh.PointerToSymbolTable, 0);
for(i=0; i<obj->fh.NumberOfSymbols; i+=numaux+1) {
Bseek(f, base+obj->fh.PointerToSymbolTable+sizeof(symbuf)*i, 0);
if(Bread(f, symbuf, sizeof symbuf) != sizeof symbuf)
goto bad;
if((symbuf[0] == 0) && (symbuf[1] == 0) &&
(symbuf[2] == 0) && (symbuf[3] == 0)) {
l = le32(&symbuf[4]);
obj->pesym[i].name = (char*)&obj->snames[l];
} else { // sym name length <= 8
obj->pesym[i].name = mal(9);
strncpy(obj->pesym[i].name, (char*)symbuf, 8);
obj->pesym[i].name[8] = 0;
}
obj->pesym[i].value = le32(&symbuf[8]);
obj->pesym[i].sectnum = le16(&symbuf[12]);
obj->pesym[i].sclass = symbuf[16];
obj->pesym[i].aux = symbuf[17];
obj->pesym[i].type = le16(&symbuf[14]);
numaux = obj->pesym[i].aux;
if (numaux < 0)
numaux = 0;
}
// create symbols for mapped sections
for(i=0; i<obj->nsect; i++) {
sect = &obj->sect[i];
if(sect->sh.Characteristics&IMAGE_SCN_MEM_DISCARDABLE)
continue;
if((sect->sh.Characteristics&(IMAGE_SCN_CNT_CODE|IMAGE_SCN_CNT_INITIALIZED_DATA|IMAGE_SCN_CNT_UNINITIALIZED_DATA)) == 0) {
// This has been seen for .idata sections, which we
// want to ignore. See issues 5106 and 5273.
continue;
}
if(map(obj, sect) < 0)
goto bad;
name = smprint("%s(%s)", pkg, sect->name);
s = linklookup(ctxt, name, ctxt->version);
free(name);
switch(sect->sh.Characteristics&(IMAGE_SCN_CNT_UNINITIALIZED_DATA|IMAGE_SCN_CNT_INITIALIZED_DATA|
IMAGE_SCN_MEM_READ|IMAGE_SCN_MEM_WRITE|IMAGE_SCN_CNT_CODE|IMAGE_SCN_MEM_EXECUTE)) {
case IMAGE_SCN_CNT_INITIALIZED_DATA|IMAGE_SCN_MEM_READ: //.rdata
s->type = SRODATA;
break;
case IMAGE_SCN_CNT_UNINITIALIZED_DATA|IMAGE_SCN_MEM_READ|IMAGE_SCN_MEM_WRITE: //.bss
s->type = SBSS;
break;
case IMAGE_SCN_CNT_INITIALIZED_DATA|IMAGE_SCN_MEM_READ|IMAGE_SCN_MEM_WRITE: //.data
s->type = SDATA;
break;
case IMAGE_SCN_CNT_CODE|IMAGE_SCN_MEM_EXECUTE|IMAGE_SCN_MEM_READ: //.text
s->type = STEXT;
break;
default:
werrstr("unexpected flags %#08ux for PE section %s", sect->sh.Characteristics, sect->name);
goto bad;
}
s->p = sect->base;
s->np = sect->size;
s->size = sect->size;
sect->sym = s;
if(strcmp(sect->name, ".rsrc") == 0)
setpersrc(sect->sym);
}
// load relocations
for(i=0; i<obj->nsect; i++) {
rsect = &obj->sect[i];
if(rsect->sym == 0 || rsect->sh.NumberOfRelocations == 0)
continue;
if(rsect->sh.Characteristics&IMAGE_SCN_MEM_DISCARDABLE)
continue;
if((sect->sh.Characteristics&(IMAGE_SCN_CNT_CODE|IMAGE_SCN_CNT_INITIALIZED_DATA|IMAGE_SCN_CNT_UNINITIALIZED_DATA)) == 0) {
// This has been seen for .idata sections, which we
// want to ignore. See issues 5106 and 5273.
continue;
}
r = mal(rsect->sh.NumberOfRelocations*sizeof r[0]);
Bseek(f, obj->base+rsect->sh.PointerToRelocations, 0);
for(j=0; j<rsect->sh.NumberOfRelocations; j++) {
rp = &r[j];
if(Bread(f, symbuf, 10) != 10)
goto bad;
uint32 rva, symindex;
uint16 type;
rva = le32(&symbuf[0]);
symindex = le32(&symbuf[4]);
type = le16(&symbuf[8]);
if(readsym(obj, symindex, &sym) < 0)
goto bad;
if(sym->sym == nil) {
werrstr("reloc of invalid sym %s idx=%d type=%d", sym->name, symindex, sym->type);
goto bad;
}
rp->sym = sym->sym;
rp->siz = 4;
rp->off = rva;
switch(type) {
default:
diag("%s: unknown relocation type %d;", pn, type);
case IMAGE_REL_I386_REL32:
case IMAGE_REL_AMD64_REL32:
case IMAGE_REL_AMD64_ADDR32: // R_X86_64_PC32
case IMAGE_REL_AMD64_ADDR32NB:
rp->type = R_PCREL;
rp->add = (int32)le32(rsect->base+rp->off);
break;
case IMAGE_REL_I386_DIR32NB:
case IMAGE_REL_I386_DIR32:
rp->type = R_ADDR;
// load addend from image
rp->add = (int32)le32(rsect->base+rp->off);
break;
case IMAGE_REL_AMD64_ADDR64: // R_X86_64_64
rp->siz = 8;
rp->type = R_ADDR;
// load addend from image
rp->add = le64(rsect->base+rp->off);
break;
}
// ld -r could generate multiple section symbols for the
// same section but with different values, we have to take
// that into account
if (obj->pesym[symindex].name[0] == '.')
rp->add += obj->pesym[symindex].value;
}
qsort(r, rsect->sh.NumberOfRelocations, sizeof r[0], rbyoff);
s = rsect->sym;
s->r = r;
s->nr = rsect->sh.NumberOfRelocations;
}
// enter sub-symbols into symbol table.
for(i=0; i<obj->npesym; i++) {
if(obj->pesym[i].name == 0)
continue;
if(obj->pesym[i].name[0] == '.') //skip section
continue;
if(obj->pesym[i].sectnum > 0) {
sect = &obj->sect[obj->pesym[i].sectnum-1];
if(sect->sym == 0)
continue;
}
if(readsym(obj, i, &sym) < 0)
goto bad;
s = sym->sym;
if(sym->sectnum == 0) {// extern
if(s->type == SDYNIMPORT)
s->plt = -2; // flag for dynimport in PE object files.
if (s->type == SXREF && sym->value > 0) {// global data
s->type = SDATA;
s->size = sym->value;
}
continue;
} else if (sym->sectnum > 0) {
sect = &obj->sect[sym->sectnum-1];
if(sect->sym == 0)
diag("%s: %s sym == 0!", pn, s->name);
} else {
diag("%s: %s sectnum < 0!", pn, s->name);
}
if(sect == nil)
return;
if(s->outer != S) {
if(s->dupok)
continue;
diag("%s: duplicate symbol reference: %s in both %s and %s", pn, s->name, s->outer->name, sect->sym->name);
errorexit();
}
s->sub = sect->sym->sub;
sect->sym->sub = s;
s->type = sect->sym->type | SSUB;
s->value = sym->value;
s->size = 4;
s->outer = sect->sym;
if(sect->sym->type == STEXT) {
if(s->external && !s->dupok)
diag("%s: duplicate definition of %s", pn, s->name);
s->external = 1;
}
}
// Sort outer lists by address, adding to textp.
// This keeps textp in increasing address order.
for(i=0; i<obj->nsect; i++) {
s = obj->sect[i].sym;
if(s == S)
continue;
if(s->sub)
s->sub = listsort(s->sub, valuecmp, offsetof(LSym, sub));
if(s->type == STEXT) {
if(s->onlist)
sysfatal("symbol %s listed multiple times", s->name);
s->onlist = 1;
if(ctxt->etextp)
ctxt->etextp->next = s;
else
ctxt->textp = s;
ctxt->etextp = s;
for(s = s->sub; s != S; s = s->sub) {
if(s->onlist)
sysfatal("symbol %s listed multiple times", s->name);
s->onlist = 1;
ctxt->etextp->next = s;
ctxt->etextp = s;
}
}
}
return;
bad:
diag("%s: malformed pe file: %r", pn);
}
