func machoreloc1(r *ld.Reloc, sectoff int64) int { var v uint32 rs := r.Xsym if rs.Type == ld.SHOSTOBJ || r.Type == ld.R_PCREL { if rs.Dynid < 0 { ld.Diag("reloc %d to non-macho symbol %s type=%d", r.Type, rs.Name, rs.Type) return -1 } v = uint32(rs.Dynid) v |= 1 << 27 // external relocation } else { v = uint32((rs.Sect.(*ld.Section)).Extnum) if v == 0 { ld.Diag("reloc %d to symbol %s in non-macho section %s type=%d", r.Type, rs.Name, (rs.Sect.(*ld.Section)).Name, rs.Type) return -1 } } switch r.Type { default: return -1 case ld.R_ADDR: v |= ld.MACHO_X86_64_RELOC_UNSIGNED << 28 case ld.R_CALL: v |= 1 << 24 // pc-relative bit v |= ld.MACHO_X86_64_RELOC_BRANCH << 28 // NOTE: Only works with 'external' relocation. Forced above. case ld.R_PCREL: v |= 1 << 24 // pc-relative bit v |= ld.MACHO_X86_64_RELOC_SIGNED << 28 } switch r.Siz { default: return -1 case 1: v |= 0 << 25 case 2: v |= 1 << 25 case 4: v |= 2 << 25 case 8: v |= 3 << 25 } ld.Thearch.Lput(uint32(sectoff)) ld.Thearch.Lput(v) return 0 }
func machoreloc1(r *ld.Reloc, sectoff int64) int { var v uint32 rs := r.Xsym if rs.Type == ld.SHOSTOBJ { if rs.Dynid < 0 { ld.Diag("reloc %d to non-macho symbol %s type=%d", r.Type, rs.Name, rs.Type) return -1 } v = uint32(rs.Dynid) v |= 1 << 27 // external relocation } else { v = uint32((rs.Sect.(*ld.Section)).Extnum) if v == 0 { ld.Diag("reloc %d to symbol %s in non-macho section %s type=%d", r.Type, rs.Name, (rs.Sect.(*ld.Section)).Name, rs.Type) return -1 } } switch r.Type { default: return -1 case ld.R_ADDR: v |= ld.MACHO_GENERIC_RELOC_VANILLA << 28 case ld.R_CALL, ld.R_PCREL: v |= 1 << 24 // pc-relative bit v |= ld.MACHO_GENERIC_RELOC_VANILLA << 28 } switch r.Siz { default: return -1 case 1: v |= 0 << 25 case 2: v |= 1 << 25 case 4: v |= 2 << 25 case 8: v |= 3 << 25 } ld.Thearch.Lput(uint32(sectoff)) ld.Thearch.Lput(v) return 0 }
func adddynsym(ctxt *ld.Link, s *ld.LSym) { if s.Dynid >= 0 { return } if ld.Iself { s.Dynid = int32(ld.Nelfsym) ld.Nelfsym++ d := ld.Linklookup(ctxt, ".dynsym", 0) name := s.Extname ld.Adduint32(ctxt, d, uint32(ld.Addstring(ld.Linklookup(ctxt, ".dynstr", 0), name))) /* type */ t := ld.STB_GLOBAL << 4 if s.Cgoexport != 0 && s.Type&ld.SMASK == ld.STEXT { t |= ld.STT_FUNC } else { t |= ld.STT_OBJECT } ld.Adduint8(ctxt, d, uint8(t)) /* reserved */ ld.Adduint8(ctxt, d, 0) /* section where symbol is defined */ if s.Type == ld.SDYNIMPORT { ld.Adduint16(ctxt, d, ld.SHN_UNDEF) } else { ld.Adduint16(ctxt, d, 1) } /* value */ if s.Type == ld.SDYNIMPORT { ld.Adduint64(ctxt, d, 0) } else { ld.Addaddr(ctxt, d, s) } /* size of object */ ld.Adduint64(ctxt, d, uint64(s.Size)) if s.Cgoexport&ld.CgoExportDynamic == 0 && s.Dynimplib != "" && needlib(s.Dynimplib) != 0 { ld.Elfwritedynent(ld.Linklookup(ctxt, ".dynamic", 0), ld.DT_NEEDED, uint64(ld.Addstring(ld.Linklookup(ctxt, ".dynstr", 0), s.Dynimplib))) } } else if ld.HEADTYPE == ld.Hdarwin { ld.Diag("adddynsym: missed symbol %s (%s)", s.Name, s.Extname) } else if ld.HEADTYPE == ld.Hwindows { } else // already taken care of { ld.Diag("adddynsym: unsupported binary format") } }
func adddynsym(ctxt *ld.Link, s *ld.LSym) { if s.Dynid >= 0 { return } if ld.Iself { s.Dynid = int32(ld.Nelfsym) ld.Nelfsym++ d := ld.Linklookup(ctxt, ".dynsym", 0) /* name */ name := s.Extname ld.Adduint32(ctxt, d, uint32(ld.Addstring(ld.Linklookup(ctxt, ".dynstr", 0), name))) /* value */ if s.Type == ld.SDYNIMPORT { ld.Adduint32(ctxt, d, 0) } else { ld.Addaddr(ctxt, d, s) } /* size */ ld.Adduint32(ctxt, d, 0) /* type */ t := ld.STB_GLOBAL << 4 if s.Cgoexport != 0 && s.Type&ld.SMASK == ld.STEXT { t |= ld.STT_FUNC } else { t |= ld.STT_OBJECT } ld.Adduint8(ctxt, d, uint8(t)) ld.Adduint8(ctxt, d, 0) /* shndx */ if s.Type == ld.SDYNIMPORT { ld.Adduint16(ctxt, d, ld.SHN_UNDEF) } else { ld.Adduint16(ctxt, d, 1) } } else if ld.HEADTYPE == ld.Hdarwin { ld.Diag("adddynsym: missed symbol %s (%s)", s.Name, s.Extname) } else if ld.HEADTYPE == ld.Hwindows { } else // already taken care of { ld.Diag("adddynsym: unsupported binary format") } }
func pereloc1(r *ld.Reloc, sectoff int64) bool { var v uint32 rs := r.Xsym if rs.Dynid < 0 { ld.Diag("reloc %d to non-coff symbol %s type=%d", r.Type, rs.Name, rs.Type) return false } ld.Thearch.Lput(uint32(sectoff)) ld.Thearch.Lput(uint32(rs.Dynid)) switch r.Type { default: return false case ld.R_ADDR: if r.Siz == 8 { v = ld.IMAGE_REL_AMD64_ADDR64 } else { v = ld.IMAGE_REL_AMD64_ADDR32 } case ld.R_CALL, ld.R_PCREL: v = ld.IMAGE_REL_AMD64_REL32 } ld.Thearch.Wput(uint16(v)) return true }
func addpltsym(ctxt *ld.Link, s *ld.LSym) { if s.Plt >= 0 { return } adddynsym(ctxt, s) if ld.Iself { plt := ld.Linklookup(ctxt, ".plt", 0) got := ld.Linklookup(ctxt, ".got.plt", 0) rel := ld.Linklookup(ctxt, ".rel.plt", 0) if plt.Size == 0 { elfsetupplt() } // jmpq *got+size ld.Adduint8(ctxt, plt, 0xff) ld.Adduint8(ctxt, plt, 0x25) ld.Addaddrplus(ctxt, plt, got, got.Size) // add to got: pointer to current pos in plt ld.Addaddrplus(ctxt, got, plt, plt.Size) // pushl $x ld.Adduint8(ctxt, plt, 0x68) ld.Adduint32(ctxt, plt, uint32(rel.Size)) // jmp .plt ld.Adduint8(ctxt, plt, 0xe9) ld.Adduint32(ctxt, plt, uint32(-(plt.Size + 4))) // rel ld.Addaddrplus(ctxt, rel, got, got.Size-4) ld.Adduint32(ctxt, rel, ld.ELF32_R_INFO(uint32(s.Dynid), ld.R_386_JMP_SLOT)) s.Plt = int32(plt.Size - 16) } else if ld.HEADTYPE == ld.Hdarwin { // Same laziness as in 6l. plt := ld.Linklookup(ctxt, ".plt", 0) addgotsym(ctxt, s) ld.Adduint32(ctxt, ld.Linklookup(ctxt, ".linkedit.plt", 0), uint32(s.Dynid)) // jmpq *got+size(IP) s.Plt = int32(plt.Size) ld.Adduint8(ctxt, plt, 0xff) ld.Adduint8(ctxt, plt, 0x25) ld.Addaddrplus(ctxt, plt, ld.Linklookup(ctxt, ".got", 0), int64(s.Got)) } else { ld.Diag("addpltsym: unsupported binary format") } }
func addgotsyminternal(ctxt *ld.Link, s *ld.LSym) { if s.Got >= 0 { return } got := ld.Linklookup(ctxt, ".got", 0) s.Got = int32(got.Size) ld.Addaddrplus(ctxt, got, s, 0) if ld.Iself { } else { ld.Diag("addgotsyminternal: unsupported binary format") } }
func adddynlib(lib string) { if needlib(lib) == 0 { return } if ld.Iself { s := ld.Linklookup(ld.Ctxt, ".dynstr", 0) if s.Size == 0 { ld.Addstring(s, "") } ld.Elfwritedynent(ld.Linklookup(ld.Ctxt, ".dynamic", 0), ld.DT_NEEDED, uint64(ld.Addstring(s, lib))) } else { ld.Diag("adddynlib: unsupported binary format") } }
// Return the value of .TOC. for symbol s func symtoc(s *ld.LSym) int64 { var toc *ld.LSym if s.Outer != nil { toc = ld.Linkrlookup(ld.Ctxt, ".TOC.", int(s.Outer.Version)) } else { toc = ld.Linkrlookup(ld.Ctxt, ".TOC.", int(s.Version)) } if toc == nil { ld.Diag("TOC-relative relocation in object without .TOC.") return 0 } return toc.Value }
func adddynsym(ctxt *ld.Link, s *ld.LSym) { if s.Dynid >= 0 { return } if ld.Iself { s.Dynid = int32(ld.Nelfsym) ld.Nelfsym++ d := ld.Linklookup(ctxt, ".dynsym", 0) /* name */ name := s.Extname ld.Adduint32(ctxt, d, uint32(ld.Addstring(ld.Linklookup(ctxt, ".dynstr", 0), name))) /* value */ if s.Type == ld.SDYNIMPORT { ld.Adduint32(ctxt, d, 0) } else { ld.Addaddr(ctxt, d, s) } /* size */ ld.Adduint32(ctxt, d, 0) /* type */ t := ld.STB_GLOBAL << 4 if (s.Cgoexport&ld.CgoExportDynamic != 0) && s.Type&ld.SMASK == ld.STEXT { t |= ld.STT_FUNC } else { t |= ld.STT_OBJECT } ld.Adduint8(ctxt, d, uint8(t)) ld.Adduint8(ctxt, d, 0) /* shndx */ if s.Type == ld.SDYNIMPORT { ld.Adduint16(ctxt, d, ld.SHN_UNDEF) } else { ld.Adduint16(ctxt, d, 1) } } else { ld.Diag("adddynsym: unsupported binary format") } }
func adddynsym(ctxt *ld.Link, s *ld.LSym) { if s.Dynid >= 0 { return } if ld.Iself { s.Dynid = int32(ld.Nelfsym) ld.Nelfsym++ d := ld.Linklookup(ctxt, ".dynsym", 0) name := s.Extname ld.Adduint32(ctxt, d, uint32(ld.Addstring(ld.Linklookup(ctxt, ".dynstr", 0), name))) /* type */ t := ld.STB_GLOBAL << 4 if s.Cgoexport != 0 && s.Type&ld.SMASK == ld.STEXT { t |= ld.STT_FUNC } else { t |= ld.STT_OBJECT } ld.Adduint8(ctxt, d, uint8(t)) /* reserved */ ld.Adduint8(ctxt, d, 0) /* section where symbol is defined */ if s.Type == ld.SDYNIMPORT { ld.Adduint16(ctxt, d, ld.SHN_UNDEF) } else { ld.Adduint16(ctxt, d, 1) } /* value */ if s.Type == ld.SDYNIMPORT { ld.Adduint64(ctxt, d, 0) } else { ld.Addaddr(ctxt, d, s) } /* size of object */ ld.Adduint64(ctxt, d, uint64(s.Size)) } else { ld.Diag("adddynsym: unsupported binary format") } }
func addgotsym(ctxt *ld.Link, s *ld.LSym) { if s.Got >= 0 { return } adddynsym(ctxt, s) got := ld.Linklookup(ctxt, ".got", 0) s.Got = int32(got.Size) ld.Adduint32(ctxt, got, 0) if ld.Iself { rel := ld.Linklookup(ctxt, ".rel", 0) ld.Addaddrplus(ctxt, rel, got, int64(s.Got)) ld.Adduint32(ctxt, rel, ld.ELF32_R_INFO(uint32(s.Dynid), ld.R_ARM_GLOB_DAT)) } else { ld.Diag("addgotsym: unsupported binary format") } }
func addpltsym(ctxt *ld.Link, s *ld.LSym) { if s.Plt >= 0 { return } adddynsym(ctxt, s) if ld.Iself { plt := ld.Linklookup(ctxt, ".plt", 0) rela := ld.Linklookup(ctxt, ".rela.plt", 0) if plt.Size == 0 { elfsetupplt() } // Create the glink resolver if necessary glink := ensureglinkresolver() // Write symbol resolver stub (just a branch to the // glink resolver stub) r := ld.Addrel(glink) r.Sym = glink r.Off = int32(glink.Size) r.Siz = 4 r.Type = ld.R_CALLPOWER ld.Adduint32(ctxt, glink, 0x48000000) // b .glink // In the ppc64 ABI, the dynamic linker is responsible // for writing the entire PLT. We just need to // reserve 8 bytes for each PLT entry and generate a // JMP_SLOT dynamic relocation for it. // // TODO(austin): ABI v1 is different s.Plt = int32(plt.Size) plt.Size += 8 ld.Addaddrplus(ctxt, rela, plt, int64(s.Plt)) ld.Adduint64(ctxt, rela, ld.ELF64_R_INFO(uint32(s.Dynid), ld.R_PPC64_JMP_SLOT)) ld.Adduint64(ctxt, rela, 0) } else { ld.Diag("addpltsym: unsupported binary format") } }
func addgotsym(s *ld.LSym) { if s.Got >= 0 { return } adddynsym(ld.Ctxt, s) got := ld.Linklookup(ld.Ctxt, ".got", 0) s.Got = int32(got.Size) ld.Adduint64(ld.Ctxt, got, 0) if ld.Iself { rela := ld.Linklookup(ld.Ctxt, ".rela", 0) ld.Addaddrplus(ld.Ctxt, rela, got, int64(s.Got)) ld.Adduint64(ld.Ctxt, rela, ld.ELF64_R_INFO(uint32(s.Dynid), ld.R_X86_64_GLOB_DAT)) ld.Adduint64(ld.Ctxt, rela, 0) } else if ld.HEADTYPE == ld.Hdarwin { ld.Adduint32(ld.Ctxt, ld.Linklookup(ld.Ctxt, ".linkedit.got", 0), uint32(s.Dynid)) } else { ld.Diag("addgotsym: unsupported binary format") } }
func addpltsym(ctxt *ld.Link, s *ld.LSym) { if s.Plt >= 0 { return } adddynsym(ctxt, s) if ld.Iself { plt := ld.Linklookup(ctxt, ".plt", 0) got := ld.Linklookup(ctxt, ".got.plt", 0) rel := ld.Linklookup(ctxt, ".rel.plt", 0) if plt.Size == 0 { elfsetupplt() } // .got entry s.Got = int32(got.Size) // In theory, all GOT should point to the first PLT entry, // Linux/ARM's dynamic linker will do that for us, but FreeBSD/ARM's // dynamic linker won't, so we'd better do it ourselves. ld.Addaddrplus(ctxt, got, plt, 0) // .plt entry, this depends on the .got entry s.Plt = int32(plt.Size) addpltreloc(ctxt, plt, got, s, ld.R_PLT0) // add lr, pc, #0xXX00000 addpltreloc(ctxt, plt, got, s, ld.R_PLT1) // add lr, lr, #0xYY000 addpltreloc(ctxt, plt, got, s, ld.R_PLT2) // ldr pc, [lr, #0xZZZ]! // rel ld.Addaddrplus(ctxt, rel, got, int64(s.Got)) ld.Adduint32(ctxt, rel, ld.ELF32_R_INFO(uint32(s.Dynid), ld.R_ARM_JUMP_SLOT)) } else { ld.Diag("addpltsym: unsupported binary format") } }
func adddynrel(s *ld.LSym, r *ld.Reloc) { targ := r.Sym ld.Ctxt.Cursym = s switch r.Type { default: if r.Type >= 256 { ld.Diag("unexpected relocation type %d", r.Type) return } // Handle relocations found in ELF object files. case 256 + ld.R_PPC64_REL24: r.Type = ld.R_CALLPOWER // This is a local call, so the caller isn't setting // up r12 and r2 is the same for the caller and // callee. Hence, we need to go to the local entry // point. (If we don't do this, the callee will try // to use r12 to compute r2.) r.Add += int64(r.Sym.Localentry) * 4 if targ.Type == ld.SDYNIMPORT { // Should have been handled in elfsetupplt ld.Diag("unexpected R_PPC64_REL24 for dyn import") } return case 256 + ld.R_PPC64_ADDR64: r.Type = ld.R_ADDR if targ.Type == ld.SDYNIMPORT { // These happen in .toc sections adddynsym(ld.Ctxt, targ) rela := ld.Linklookup(ld.Ctxt, ".rela", 0) ld.Addaddrplus(ld.Ctxt, rela, s, int64(r.Off)) ld.Adduint64(ld.Ctxt, rela, ld.ELF64_R_INFO(uint32(targ.Dynid), ld.R_PPC64_ADDR64)) ld.Adduint64(ld.Ctxt, rela, uint64(r.Add)) r.Type = 256 // ignore during relocsym } return case 256 + ld.R_PPC64_TOC16: r.Type = ld.R_POWER_TOC r.Variant = ld.RV_POWER_LO | ld.RV_CHECK_OVERFLOW return case 256 + ld.R_PPC64_TOC16_LO: r.Type = ld.R_POWER_TOC r.Variant = ld.RV_POWER_LO return case 256 + ld.R_PPC64_TOC16_HA: r.Type = ld.R_POWER_TOC r.Variant = ld.RV_POWER_HA | ld.RV_CHECK_OVERFLOW return case 256 + ld.R_PPC64_TOC16_HI: r.Type = ld.R_POWER_TOC r.Variant = ld.RV_POWER_HI | ld.RV_CHECK_OVERFLOW return case 256 + ld.R_PPC64_TOC16_DS: r.Type = ld.R_POWER_TOC r.Variant = ld.RV_POWER_DS | ld.RV_CHECK_OVERFLOW return case 256 + ld.R_PPC64_TOC16_LO_DS: r.Type = ld.R_POWER_TOC r.Variant = ld.RV_POWER_DS return case 256 + ld.R_PPC64_REL16_LO: r.Type = ld.R_PCREL r.Variant = ld.RV_POWER_LO r.Add += 2 // Compensate for relocation size of 2 return case 256 + ld.R_PPC64_REL16_HI: r.Type = ld.R_PCREL r.Variant = ld.RV_POWER_HI | ld.RV_CHECK_OVERFLOW r.Add += 2 return case 256 + ld.R_PPC64_REL16_HA: r.Type = ld.R_PCREL r.Variant = ld.RV_POWER_HA | ld.RV_CHECK_OVERFLOW r.Add += 2 return } // Handle references to ELF symbols from our own object files. if targ.Type != ld.SDYNIMPORT { return } // TODO(austin): Translate our relocations to ELF ld.Diag("unsupported relocation for dynamic symbol %s (type=%d stype=%d)", targ.Name, r.Type, targ.Type) }
func archrelocvariant(r *ld.Reloc, s *ld.LSym, t int64) int64 { switch r.Variant & ld.RV_TYPE_MASK { default: ld.Diag("unexpected relocation variant %d", r.Variant) fallthrough case ld.RV_NONE: return t case ld.RV_POWER_LO: if r.Variant&ld.RV_CHECK_OVERFLOW != 0 { // Whether to check for signed or unsigned // overflow depends on the instruction var o1 uint32 if ld.Ctxt.Arch.ByteOrder == binary.BigEndian { o1 = ld.Be32(s.P[r.Off-2:]) } else { o1 = ld.Le32(s.P[r.Off:]) } switch o1 >> 26 { case 24, // ori 26, // xori 28: // andi if t>>16 != 0 { goto overflow } default: if int64(int16(t)) != t { goto overflow } } } return int64(int16(t)) case ld.RV_POWER_HA: t += 0x8000 fallthrough // Fallthrough case ld.RV_POWER_HI: t >>= 16 if r.Variant&ld.RV_CHECK_OVERFLOW != 0 { // Whether to check for signed or unsigned // overflow depends on the instruction var o1 uint32 if ld.Ctxt.Arch.ByteOrder == binary.BigEndian { o1 = ld.Be32(s.P[r.Off-2:]) } else { o1 = ld.Le32(s.P[r.Off:]) } switch o1 >> 26 { case 25, // oris 27, // xoris 29: // andis if t>>16 != 0 { goto overflow } default: if int64(int16(t)) != t { goto overflow } } } return int64(int16(t)) case ld.RV_POWER_DS: var o1 uint32 if ld.Ctxt.Arch.ByteOrder == binary.BigEndian { o1 = uint32(ld.Be16(s.P[r.Off:])) } else { o1 = uint32(ld.Le16(s.P[r.Off:])) } if t&3 != 0 { ld.Diag("relocation for %s+%d is not aligned: %d", r.Sym.Name, r.Off, t) } if (r.Variant&ld.RV_CHECK_OVERFLOW != 0) && int64(int16(t)) != t { goto overflow } return int64(o1)&0x3 | int64(int16(t)) } overflow: ld.Diag("relocation for %s+%d is too big: %d", r.Sym.Name, r.Off, t) return t }
func machoreloc1(r *ld.Reloc, sectoff int64) int { var v uint32 rs := r.Xsym // ld64 has a bug handling MACHO_ARM64_RELOC_UNSIGNED with !extern relocation. // see cmd/internal/ld/data.go for details. The workarond is that don't use !extern // UNSIGNED relocation at all. if rs.Type == obj.SHOSTOBJ || r.Type == obj.R_CALLARM64 || r.Type == obj.R_ADDRARM64 || r.Type == obj.R_ADDR { if rs.Dynid < 0 { ld.Diag("reloc %d to non-macho symbol %s type=%d", r.Type, rs.Name, rs.Type) return -1 } v = uint32(rs.Dynid) v |= 1 << 27 // external relocation } else { v = uint32((rs.Sect.(*ld.Section)).Extnum) if v == 0 { ld.Diag("reloc %d to symbol %s in non-macho section %s type=%d", r.Type, rs.Name, (rs.Sect.(*ld.Section)).Name, rs.Type) return -1 } } switch r.Type { default: return -1 case obj.R_ADDR: v |= ld.MACHO_ARM64_RELOC_UNSIGNED << 28 case obj.R_CALLARM64: if r.Xadd != 0 { ld.Diag("ld64 doesn't allow BR26 reloc with non-zero addend: %s+%d", rs.Name, r.Xadd) } v |= 1 << 24 // pc-relative bit v |= ld.MACHO_ARM64_RELOC_BRANCH26 << 28 case obj.R_ADDRARM64: r.Siz = 4 // Two relocation entries: MACHO_ARM64_RELOC_PAGEOFF12 MACHO_ARM64_RELOC_PAGE21 // if r.Xadd is non-zero, add two MACHO_ARM64_RELOC_ADDEND. if r.Xadd != 0 { ld.Thearch.Lput(uint32(sectoff + 4)) ld.Thearch.Lput((ld.MACHO_ARM64_RELOC_ADDEND << 28) | (2 << 25) | uint32(r.Xadd&0xffffff)) } ld.Thearch.Lput(uint32(sectoff + 4)) ld.Thearch.Lput(v | (ld.MACHO_ARM64_RELOC_PAGEOFF12 << 28) | (2 << 25)) if r.Xadd != 0 { ld.Thearch.Lput(uint32(sectoff)) ld.Thearch.Lput((ld.MACHO_ARM64_RELOC_ADDEND << 28) | (2 << 25) | uint32(r.Xadd&0xffffff)) } v |= 1 << 24 // pc-relative bit v |= ld.MACHO_ARM64_RELOC_PAGE21 << 28 } switch r.Siz { default: return -1 case 1: v |= 0 << 25 case 2: v |= 1 << 25 case 4: v |= 2 << 25 case 8: v |= 3 << 25 } ld.Thearch.Lput(uint32(sectoff)) ld.Thearch.Lput(v) return 0 }
func archreloc(r *ld.Reloc, s *ld.LSym, val *int64) int { if ld.Linkmode == ld.LinkExternal { switch r.Type { case ld.R_CALLARM: r.Done = 0 // set up addend for eventual relocation via outer symbol. rs := r.Sym r.Xadd = r.Add if r.Xadd&0x800000 != 0 { r.Xadd |= ^0xffffff } r.Xadd *= 4 for rs.Outer != nil { r.Xadd += ld.Symaddr(rs) - ld.Symaddr(rs.Outer) rs = rs.Outer } if rs.Type != ld.SHOSTOBJ && rs.Sect == nil { ld.Diag("missing section for %s", rs.Name) } r.Xsym = rs // ld64 for arm seems to want the symbol table to contain offset // into the section rather than pseudo virtual address that contains // the section load address. // we need to compensate that by removing the instruction's address // from addend. if ld.HEADTYPE == ld.Hdarwin { r.Xadd -= ld.Symaddr(s) + int64(r.Off) } *val = int64(braddoff(int32(0xff000000&uint32(r.Add)), int32(0xffffff&uint32(r.Xadd/4)))) return 0 } return -1 } switch r.Type { case ld.R_CONST: *val = r.Add return 0 case ld.R_GOTOFF: *val = ld.Symaddr(r.Sym) + r.Add - ld.Symaddr(ld.Linklookup(ld.Ctxt, ".got", 0)) return 0 // The following three arch specific relocations are only for generation of // Linux/ARM ELF's PLT entry (3 assembler instruction) case ld.R_PLT0: // add ip, pc, #0xXX00000 if ld.Symaddr(ld.Linklookup(ld.Ctxt, ".got.plt", 0)) < ld.Symaddr(ld.Linklookup(ld.Ctxt, ".plt", 0)) { ld.Diag(".got.plt should be placed after .plt section.") } *val = 0xe28fc600 + (0xff & (int64(uint32(ld.Symaddr(r.Sym)-(ld.Symaddr(ld.Linklookup(ld.Ctxt, ".plt", 0))+int64(r.Off))+r.Add)) >> 20)) return 0 case ld.R_PLT1: // add ip, ip, #0xYY000 *val = 0xe28cca00 + (0xff & (int64(uint32(ld.Symaddr(r.Sym)-(ld.Symaddr(ld.Linklookup(ld.Ctxt, ".plt", 0))+int64(r.Off))+r.Add+4)) >> 12)) return 0 case ld.R_PLT2: // ldr pc, [ip, #0xZZZ]! *val = 0xe5bcf000 + (0xfff & int64(uint32(ld.Symaddr(r.Sym)-(ld.Symaddr(ld.Linklookup(ld.Ctxt, ".plt", 0))+int64(r.Off))+r.Add+8))) return 0 case ld.R_CALLARM: // bl XXXXXX or b YYYYYY *val = int64(braddoff(int32(0xff000000&uint32(r.Add)), int32(0xffffff&uint32((ld.Symaddr(r.Sym)+int64((uint32(r.Add))*4)-(s.Value+int64(r.Off)))/4)))) return 0 } return -1 }
func asmb() { if ld.Debug['v'] != 0 { fmt.Fprintf(&ld.Bso, "%5.2f asmb\n", obj.Cputime()) } ld.Bflush(&ld.Bso) if ld.Debug['v'] != 0 { fmt.Fprintf(&ld.Bso, "%5.2f codeblk\n", obj.Cputime()) } ld.Bflush(&ld.Bso) if ld.Iself { ld.Asmbelfsetup() } sect := ld.Segtext.Sect ld.Cseek(int64(sect.Vaddr - ld.Segtext.Vaddr + ld.Segtext.Fileoff)) ld.Codeblk(int64(sect.Vaddr), int64(sect.Length)) for sect = sect.Next; sect != nil; sect = sect.Next { ld.Cseek(int64(sect.Vaddr - ld.Segtext.Vaddr + ld.Segtext.Fileoff)) ld.Datblk(int64(sect.Vaddr), int64(sect.Length)) } if ld.Segrodata.Filelen > 0 { if ld.Debug['v'] != 0 { fmt.Fprintf(&ld.Bso, "%5.2f rodatblk\n", obj.Cputime()) } ld.Bflush(&ld.Bso) ld.Cseek(int64(ld.Segrodata.Fileoff)) ld.Datblk(int64(ld.Segrodata.Vaddr), int64(ld.Segrodata.Filelen)) } if ld.Debug['v'] != 0 { fmt.Fprintf(&ld.Bso, "%5.2f datblk\n", obj.Cputime()) } ld.Bflush(&ld.Bso) ld.Cseek(int64(ld.Segdata.Fileoff)) ld.Datblk(int64(ld.Segdata.Vaddr), int64(ld.Segdata.Filelen)) machlink := int64(0) if ld.HEADTYPE == ld.Hdarwin { if ld.Debug['v'] != 0 { fmt.Fprintf(&ld.Bso, "%5.2f dwarf\n", obj.Cputime()) } dwarfoff := ld.Rnd(int64(uint64(ld.HEADR)+ld.Segtext.Length), int64(ld.INITRND)) + ld.Rnd(int64(ld.Segdata.Filelen), int64(ld.INITRND)) ld.Cseek(dwarfoff) ld.Segdwarf.Fileoff = uint64(ld.Cpos()) ld.Dwarfemitdebugsections() ld.Segdwarf.Filelen = uint64(ld.Cpos()) - ld.Segdwarf.Fileoff machlink = ld.Domacholink() } switch ld.HEADTYPE { default: ld.Diag("unknown header type %d", ld.HEADTYPE) fallthrough case ld.Hplan9, ld.Helf: break case ld.Hdarwin: ld.Debug['8'] = 1 /* 64-bit addresses */ case ld.Hlinux, ld.Hfreebsd, ld.Hnetbsd, ld.Hopenbsd, ld.Hdragonfly, ld.Hsolaris: ld.Debug['8'] = 1 /* 64-bit addresses */ case ld.Hnacl, ld.Hwindows: break } ld.Symsize = 0 ld.Spsize = 0 ld.Lcsize = 0 symo := int64(0) if ld.Debug['s'] == 0 { if ld.Debug['v'] != 0 { fmt.Fprintf(&ld.Bso, "%5.2f sym\n", obj.Cputime()) } ld.Bflush(&ld.Bso) switch ld.HEADTYPE { default: case ld.Hplan9, ld.Helf: ld.Debug['s'] = 1 symo = int64(ld.Segdata.Fileoff + ld.Segdata.Filelen) case ld.Hdarwin: symo = int64(ld.Segdata.Fileoff + uint64(ld.Rnd(int64(ld.Segdata.Filelen), int64(ld.INITRND))) + uint64(machlink)) case ld.Hlinux, ld.Hfreebsd, ld.Hnetbsd, ld.Hopenbsd, ld.Hdragonfly, ld.Hsolaris, ld.Hnacl: symo = int64(ld.Segdata.Fileoff + ld.Segdata.Filelen) symo = ld.Rnd(symo, int64(ld.INITRND)) case ld.Hwindows: symo = int64(ld.Segdata.Fileoff + ld.Segdata.Filelen) symo = ld.Rnd(symo, ld.PEFILEALIGN) } ld.Cseek(symo) switch ld.HEADTYPE { default: if ld.Iself { ld.Cseek(symo) ld.Asmelfsym() ld.Cflush() ld.Cwrite(ld.Elfstrdat) if ld.Debug['v'] != 0 { fmt.Fprintf(&ld.Bso, "%5.2f dwarf\n", obj.Cputime()) } ld.Dwarfemitdebugsections() if ld.Linkmode == ld.LinkExternal { ld.Elfemitreloc() } } case ld.Hplan9: ld.Asmplan9sym() ld.Cflush() sym := ld.Linklookup(ld.Ctxt, "pclntab", 0) if sym != nil { ld.Lcsize = int32(len(sym.P)) for i := 0; int32(i) < ld.Lcsize; i++ { ld.Cput(uint8(sym.P[i])) } ld.Cflush() } case ld.Hwindows: if ld.Debug['v'] != 0 { fmt.Fprintf(&ld.Bso, "%5.2f dwarf\n", obj.Cputime()) } ld.Dwarfemitdebugsections() case ld.Hdarwin: if ld.Linkmode == ld.LinkExternal { ld.Machoemitreloc() } } } if ld.Debug['v'] != 0 { fmt.Fprintf(&ld.Bso, "%5.2f headr\n", obj.Cputime()) } ld.Bflush(&ld.Bso) ld.Cseek(0) switch ld.HEADTYPE { default: case ld.Hplan9: /* plan9 */ magic := int32(4*26*26 + 7) magic |= 0x00008000 /* fat header */ ld.Lputb(uint32(magic)) /* magic */ ld.Lputb(uint32(ld.Segtext.Filelen)) /* sizes */ ld.Lputb(uint32(ld.Segdata.Filelen)) ld.Lputb(uint32(ld.Segdata.Length - ld.Segdata.Filelen)) ld.Lputb(uint32(ld.Symsize)) /* nsyms */ vl := ld.Entryvalue() ld.Lputb(PADDR(uint32(vl))) /* va of entry */ ld.Lputb(uint32(ld.Spsize)) /* sp offsets */ ld.Lputb(uint32(ld.Lcsize)) /* line offsets */ ld.Vputb(uint64(vl)) /* va of entry */ case ld.Hdarwin: ld.Asmbmacho() case ld.Hlinux, ld.Hfreebsd, ld.Hnetbsd, ld.Hopenbsd, ld.Hdragonfly, ld.Hsolaris, ld.Hnacl: ld.Asmbelf(symo) case ld.Hwindows: ld.Asmbpe() } ld.Cflush() }
func adddynrel(s *ld.LSym, r *ld.Reloc) { targ := r.Sym ld.Ctxt.Cursym = s switch r.Type { default: if r.Type >= 256 { ld.Diag("unexpected relocation type %d", r.Type) return } // Handle relocations found in ELF object files. case 256 + ld.R_X86_64_PC32: if targ.Type == ld.SDYNIMPORT { ld.Diag("unexpected R_X86_64_PC32 relocation for dynamic symbol %s", targ.Name) } if targ.Type == 0 || targ.Type == ld.SXREF { ld.Diag("unknown symbol %s in pcrel", targ.Name) } r.Type = ld.R_PCREL r.Add += 4 return case 256 + ld.R_X86_64_PLT32: r.Type = ld.R_PCREL r.Add += 4 if targ.Type == ld.SDYNIMPORT { addpltsym(targ) r.Sym = ld.Linklookup(ld.Ctxt, ".plt", 0) r.Add += int64(targ.Plt) } return case 256 + ld.R_X86_64_GOTPCREL: if targ.Type != ld.SDYNIMPORT { // have symbol if r.Off >= 2 && s.P[r.Off-2] == 0x8b { // turn MOVQ of GOT entry into LEAQ of symbol itself s.P[r.Off-2] = 0x8d r.Type = ld.R_PCREL r.Add += 4 return } } // fall back to using GOT and hope for the best (CMOV*) // TODO: just needs relocation, no need to put in .dynsym addgotsym(targ) r.Type = ld.R_PCREL r.Sym = ld.Linklookup(ld.Ctxt, ".got", 0) r.Add += 4 r.Add += int64(targ.Got) return case 256 + ld.R_X86_64_64: if targ.Type == ld.SDYNIMPORT { ld.Diag("unexpected R_X86_64_64 relocation for dynamic symbol %s", targ.Name) } r.Type = ld.R_ADDR return // Handle relocations found in Mach-O object files. case 512 + ld.MACHO_X86_64_RELOC_UNSIGNED*2 + 0, 512 + ld.MACHO_X86_64_RELOC_SIGNED*2 + 0, 512 + ld.MACHO_X86_64_RELOC_BRANCH*2 + 0: // TODO: What is the difference between all these? r.Type = ld.R_ADDR if targ.Type == ld.SDYNIMPORT { ld.Diag("unexpected reloc for dynamic symbol %s", targ.Name) } return case 512 + ld.MACHO_X86_64_RELOC_BRANCH*2 + 1: if targ.Type == ld.SDYNIMPORT { addpltsym(targ) r.Sym = ld.Linklookup(ld.Ctxt, ".plt", 0) r.Add = int64(targ.Plt) r.Type = ld.R_PCREL return } fallthrough // fall through case 512 + ld.MACHO_X86_64_RELOC_UNSIGNED*2 + 1, 512 + ld.MACHO_X86_64_RELOC_SIGNED*2 + 1, 512 + ld.MACHO_X86_64_RELOC_SIGNED_1*2 + 1, 512 + ld.MACHO_X86_64_RELOC_SIGNED_2*2 + 1, 512 + ld.MACHO_X86_64_RELOC_SIGNED_4*2 + 1: r.Type = ld.R_PCREL if targ.Type == ld.SDYNIMPORT { ld.Diag("unexpected pc-relative reloc for dynamic symbol %s", targ.Name) } return case 512 + ld.MACHO_X86_64_RELOC_GOT_LOAD*2 + 1: if targ.Type != ld.SDYNIMPORT { // have symbol // turn MOVQ of GOT entry into LEAQ of symbol itself if r.Off < 2 || s.P[r.Off-2] != 0x8b { ld.Diag("unexpected GOT_LOAD reloc for non-dynamic symbol %s", targ.Name) return } s.P[r.Off-2] = 0x8d r.Type = ld.R_PCREL return } fallthrough // fall through case 512 + ld.MACHO_X86_64_RELOC_GOT*2 + 1: if targ.Type != ld.SDYNIMPORT { ld.Diag("unexpected GOT reloc for non-dynamic symbol %s", targ.Name) } addgotsym(targ) r.Type = ld.R_PCREL r.Sym = ld.Linklookup(ld.Ctxt, ".got", 0) r.Add += int64(targ.Got) return } // Handle references to ELF symbols from our own object files. if targ.Type != ld.SDYNIMPORT { return } switch r.Type { case ld.R_CALL, ld.R_PCREL: if ld.HEADTYPE == ld.Hwindows { // nothing to do, the relocation will be laid out in pereloc1 return } else { // for both ELF and Mach-O addpltsym(targ) r.Sym = ld.Linklookup(ld.Ctxt, ".plt", 0) r.Add = int64(targ.Plt) return } case ld.R_ADDR: if s.Type == ld.STEXT && ld.Iself { // The code is asking for the address of an external // function. We provide it with the address of the // correspondent GOT symbol. addgotsym(targ) r.Sym = ld.Linklookup(ld.Ctxt, ".got", 0) r.Add += int64(targ.Got) return } if s.Type != ld.SDATA { break } if ld.Iself { adddynsym(ld.Ctxt, targ) rela := ld.Linklookup(ld.Ctxt, ".rela", 0) ld.Addaddrplus(ld.Ctxt, rela, s, int64(r.Off)) if r.Siz == 8 { ld.Adduint64(ld.Ctxt, rela, ld.ELF64_R_INFO(uint32(targ.Dynid), ld.R_X86_64_64)) } else { ld.Adduint64(ld.Ctxt, rela, ld.ELF64_R_INFO(uint32(targ.Dynid), ld.R_X86_64_32)) } ld.Adduint64(ld.Ctxt, rela, uint64(r.Add)) r.Type = 256 // ignore during relocsym return } if ld.HEADTYPE == ld.Hdarwin && s.Size == int64(ld.Thearch.Ptrsize) && r.Off == 0 { // Mach-O relocations are a royal pain to lay out. // They use a compact stateful bytecode representation // that is too much bother to deal with. // Instead, interpret the C declaration // void *_Cvar_stderr = &stderr; // as making _Cvar_stderr the name of a GOT entry // for stderr. This is separate from the usual GOT entry, // just in case the C code assigns to the variable, // and of course it only works for single pointers, // but we only need to support cgo and that's all it needs. adddynsym(ld.Ctxt, targ) got := ld.Linklookup(ld.Ctxt, ".got", 0) s.Type = got.Type | ld.SSUB s.Outer = got s.Sub = got.Sub got.Sub = s s.Value = got.Size ld.Adduint64(ld.Ctxt, got, 0) ld.Adduint32(ld.Ctxt, ld.Linklookup(ld.Ctxt, ".linkedit.got", 0), uint32(targ.Dynid)) r.Type = 256 // ignore during relocsym return } if ld.HEADTYPE == ld.Hwindows { // nothing to do, the relocation will be laid out in pereloc1 return } } ld.Ctxt.Cursym = s ld.Diag("unsupported relocation for dynamic symbol %s (type=%d stype=%d)", targ.Name, r.Type, targ.Type) }
func archinit() { // getgoextlinkenabled is based on GO_EXTLINK_ENABLED when // Go was built; see ../../make.bash. if ld.Linkmode == ld.LinkAuto && obj.Getgoextlinkenabled() == "0" { ld.Linkmode = ld.LinkInternal } if ld.Flag_shared != 0 { ld.Linkmode = ld.LinkExternal } switch ld.HEADTYPE { default: if ld.Linkmode == ld.LinkAuto { ld.Linkmode = ld.LinkInternal } if ld.Linkmode == ld.LinkExternal && obj.Getgoextlinkenabled() != "1" { log.Fatalf("cannot use -linkmode=external with -H %s", ld.Headstr(int(ld.HEADTYPE))) } case ld.Hdarwin, ld.Hdragonfly, ld.Hfreebsd, ld.Hlinux, ld.Hnacl, ld.Hnetbsd, ld.Hopenbsd, ld.Hsolaris, ld.Hwindows: break } switch ld.HEADTYPE { default: ld.Diag("unknown -H option") ld.Errorexit() fallthrough case ld.Hplan9: /* plan 9 */ ld.HEADR = 32 + 8 if ld.INITTEXT == -1 { ld.INITTEXT = 0x200000 + int64(ld.HEADR) } if ld.INITDAT == -1 { ld.INITDAT = 0 } if ld.INITRND == -1 { ld.INITRND = 0x200000 } case ld.Helf: /* elf32 executable */ ld.HEADR = int32(ld.Rnd(52+3*32, 16)) if ld.INITTEXT == -1 { ld.INITTEXT = 0x80110000 } if ld.INITDAT == -1 { ld.INITDAT = 0 } if ld.INITRND == -1 { ld.INITRND = 4096 } case ld.Hdarwin: /* apple MACH */ ld.Machoinit() ld.HEADR = ld.INITIAL_MACHO_HEADR if ld.INITRND == -1 { ld.INITRND = 4096 } if ld.INITTEXT == -1 { ld.INITTEXT = 4096 + int64(ld.HEADR) } if ld.INITDAT == -1 { ld.INITDAT = 0 } case ld.Hlinux, /* elf64 executable */ ld.Hfreebsd, /* freebsd */ ld.Hnetbsd, /* netbsd */ ld.Hopenbsd, /* openbsd */ ld.Hdragonfly, /* dragonfly */ ld.Hsolaris: /* solaris */ ld.Elfinit() ld.HEADR = ld.ELFRESERVE if ld.INITTEXT == -1 { ld.INITTEXT = (1 << 22) + int64(ld.HEADR) } if ld.INITDAT == -1 { ld.INITDAT = 0 } if ld.INITRND == -1 { ld.INITRND = 4096 } case ld.Hnacl: ld.Elfinit() ld.Debug['w']++ // disable dwarf, which gets confused and is useless anyway ld.HEADR = 0x10000 ld.Funcalign = 32 if ld.INITTEXT == -1 { ld.INITTEXT = 0x20000 } if ld.INITDAT == -1 { ld.INITDAT = 0 } if ld.INITRND == -1 { ld.INITRND = 0x10000 } case ld.Hwindows: /* PE executable */ ld.Peinit() ld.HEADR = ld.PEFILEHEADR if ld.INITTEXT == -1 { ld.INITTEXT = ld.PEBASE + int64(ld.PESECTHEADR) } if ld.INITDAT == -1 { ld.INITDAT = 0 } if ld.INITRND == -1 { ld.INITRND = ld.PESECTALIGN } } if ld.INITDAT != 0 && ld.INITRND != 0 { fmt.Printf("warning: -D0x%x is ignored because of -R0x%x\n", uint64(ld.INITDAT), uint32(ld.INITRND)) } }
func archinit() { // getgoextlinkenabled is based on GO_EXTLINK_ENABLED when // Go was built; see ../../make.bash. if ld.Linkmode == ld.LinkAuto && obj.Getgoextlinkenabled() == "0" { ld.Linkmode = ld.LinkInternal } switch ld.HEADTYPE { default: if ld.Linkmode == ld.LinkAuto { ld.Linkmode = ld.LinkInternal } if ld.Linkmode == ld.LinkExternal && obj.Getgoextlinkenabled() != "1" { log.Fatalf("cannot use -linkmode=external with -H %s", ld.Headstr(int(ld.HEADTYPE))) } case ld.Hlinux, ld.Hfreebsd, ld.Hnacl, ld.Hdarwin: break } switch ld.HEADTYPE { default: ld.Diag("unknown -H option") ld.Errorexit() fallthrough case ld.Hplan9: /* plan 9 */ ld.HEADR = 32 if ld.INITTEXT == -1 { ld.INITTEXT = 4128 } if ld.INITDAT == -1 { ld.INITDAT = 0 } if ld.INITRND == -1 { ld.INITRND = 4096 } case ld.Hlinux, /* arm elf */ ld.Hfreebsd, ld.Hnetbsd, ld.Hopenbsd: ld.Debug['d'] = 0 // with dynamic linking ld.Elfinit() ld.HEADR = ld.ELFRESERVE if ld.INITTEXT == -1 { ld.INITTEXT = 0x10000 + int64(ld.HEADR) } if ld.INITDAT == -1 { ld.INITDAT = 0 } if ld.INITRND == -1 { ld.INITRND = 4096 } case ld.Hnacl: ld.Elfinit() ld.HEADR = 0x10000 ld.Funcalign = 16 if ld.INITTEXT == -1 { ld.INITTEXT = 0x20000 } if ld.INITDAT == -1 { ld.INITDAT = 0 } if ld.INITRND == -1 { ld.INITRND = 0x10000 } case ld.Hdarwin: /* apple MACH */ ld.Debug['w'] = 1 // disable DWARF generataion ld.Machoinit() ld.HEADR = ld.INITIAL_MACHO_HEADR if ld.INITTEXT == -1 { ld.INITTEXT = 4096 + int64(ld.HEADR) } if ld.INITDAT == -1 { ld.INITDAT = 0 } if ld.INITRND == -1 { ld.INITRND = 4096 } } if ld.INITDAT != 0 && ld.INITRND != 0 { fmt.Printf("warning: -D0x%x is ignored because of -R0x%x\n", uint64(ld.INITDAT), uint32(ld.INITRND)) } // embed goarm to runtime.goarm s := ld.Linklookup(ld.Ctxt, "runtime.goarm", 0) s.Type = ld.SRODATA ld.Adduint8(ld.Ctxt, s, uint8(ld.Ctxt.Goarm)) }
func addpltsym(s *ld.LSym) { if s.Plt >= 0 { return } adddynsym(ld.Ctxt, s) if ld.Iself { plt := ld.Linklookup(ld.Ctxt, ".plt", 0) got := ld.Linklookup(ld.Ctxt, ".got.plt", 0) rela := ld.Linklookup(ld.Ctxt, ".rela.plt", 0) if plt.Size == 0 { elfsetupplt() } // jmpq *got+size(IP) ld.Adduint8(ld.Ctxt, plt, 0xff) ld.Adduint8(ld.Ctxt, plt, 0x25) ld.Addpcrelplus(ld.Ctxt, plt, got, got.Size) // add to got: pointer to current pos in plt ld.Addaddrplus(ld.Ctxt, got, plt, plt.Size) // pushq $x ld.Adduint8(ld.Ctxt, plt, 0x68) ld.Adduint32(ld.Ctxt, plt, uint32((got.Size-24-8)/8)) // jmpq .plt ld.Adduint8(ld.Ctxt, plt, 0xe9) ld.Adduint32(ld.Ctxt, plt, uint32(-(plt.Size + 4))) // rela ld.Addaddrplus(ld.Ctxt, rela, got, got.Size-8) ld.Adduint64(ld.Ctxt, rela, ld.ELF64_R_INFO(uint32(s.Dynid), ld.R_X86_64_JMP_SLOT)) ld.Adduint64(ld.Ctxt, rela, 0) s.Plt = int32(plt.Size - 16) } else if ld.HEADTYPE == ld.Hdarwin { // To do lazy symbol lookup right, we're supposed // to tell the dynamic loader which library each // symbol comes from and format the link info // section just so. I'm too lazy (ha!) to do that // so for now we'll just use non-lazy pointers, // which don't need to be told which library to use. // // http://networkpx.blogspot.com/2009/09/about-lcdyldinfoonly-command.html // has details about what we're avoiding. addgotsym(s) plt := ld.Linklookup(ld.Ctxt, ".plt", 0) ld.Adduint32(ld.Ctxt, ld.Linklookup(ld.Ctxt, ".linkedit.plt", 0), uint32(s.Dynid)) // jmpq *got+size(IP) s.Plt = int32(plt.Size) ld.Adduint8(ld.Ctxt, plt, 0xff) ld.Adduint8(ld.Ctxt, plt, 0x25) ld.Addpcrelplus(ld.Ctxt, plt, ld.Linklookup(ld.Ctxt, ".got", 0), int64(s.Got)) } else { ld.Diag("addpltsym: unsupported binary format") } }
func archinit() { // getgoextlinkenabled is based on GO_EXTLINK_ENABLED when // Go was built; see ../../make.bash. if ld.Linkmode == ld.LinkAuto && obj.Getgoextlinkenabled() == "0" { ld.Linkmode = ld.LinkInternal } switch ld.HEADTYPE { default: if ld.Linkmode == ld.LinkAuto { ld.Linkmode = ld.LinkInternal } if ld.Linkmode == ld.LinkExternal && obj.Getgoextlinkenabled() != "1" { log.Fatalf("cannot use -linkmode=external with -H %s", ld.Headstr(int(ld.HEADTYPE))) } case ld.Hdarwin, ld.Hfreebsd, ld.Hlinux, ld.Hnetbsd, ld.Hopenbsd: break } switch ld.HEADTYPE { default: ld.Diag("unknown -H option") ld.Errorexit() fallthrough case ld.Hplan9: /* plan 9 */ ld.HEADR = 32 if ld.INITTEXT == -1 { ld.INITTEXT = 4096 + 32 } if ld.INITDAT == -1 { ld.INITDAT = 0 } if ld.INITRND == -1 { ld.INITRND = 4096 } case ld.Hdarwin: /* apple MACH */ ld.Machoinit() ld.HEADR = ld.INITIAL_MACHO_HEADR if ld.INITTEXT == -1 { ld.INITTEXT = 4096 + int64(ld.HEADR) } if ld.INITDAT == -1 { ld.INITDAT = 0 } if ld.INITRND == -1 { ld.INITRND = 4096 } case ld.Hlinux, /* elf32 executable */ ld.Hfreebsd, ld.Hnetbsd, ld.Hopenbsd: ld.Elfinit() ld.HEADR = ld.ELFRESERVE if ld.INITTEXT == -1 { ld.INITTEXT = 0x08048000 + int64(ld.HEADR) } if ld.INITDAT == -1 { ld.INITDAT = 0 } if ld.INITRND == -1 { ld.INITRND = 4096 } case ld.Hnacl: ld.Elfinit() ld.HEADR = 0x10000 ld.Funcalign = 32 if ld.INITTEXT == -1 { ld.INITTEXT = 0x20000 } if ld.INITDAT == -1 { ld.INITDAT = 0 } if ld.INITRND == -1 { ld.INITRND = 0x10000 } case ld.Hwindows: /* PE executable */ ld.Peinit() ld.HEADR = ld.PEFILEHEADR if ld.INITTEXT == -1 { ld.INITTEXT = ld.PEBASE + int64(ld.PESECTHEADR) } if ld.INITDAT == -1 { ld.INITDAT = 0 } if ld.INITRND == -1 { ld.INITRND = ld.PESECTALIGN } } if ld.INITDAT != 0 && ld.INITRND != 0 { fmt.Printf("warning: -D0x%x is ignored because of -R0x%x\n", uint64(ld.INITDAT), uint32(ld.INITRND)) } }
func adddynrel(s *ld.LSym, r *ld.Reloc) { targ := r.Sym ld.Ctxt.Cursym = s switch r.Type { default: if r.Type >= 256 { ld.Diag("unexpected relocation type %d", r.Type) return } // Handle relocations found in ELF object files. case 256 + ld.R_386_PC32: if targ.Type == ld.SDYNIMPORT { ld.Diag("unexpected R_386_PC32 relocation for dynamic symbol %s", targ.Name) } if targ.Type == 0 || targ.Type == ld.SXREF { ld.Diag("unknown symbol %s in pcrel", targ.Name) } r.Type = ld.R_PCREL r.Add += 4 return case 256 + ld.R_386_PLT32: r.Type = ld.R_PCREL r.Add += 4 if targ.Type == ld.SDYNIMPORT { addpltsym(ld.Ctxt, targ) r.Sym = ld.Linklookup(ld.Ctxt, ".plt", 0) r.Add += int64(targ.Plt) } return case 256 + ld.R_386_GOT32: if targ.Type != ld.SDYNIMPORT { // have symbol if r.Off >= 2 && s.P[r.Off-2] == 0x8b { // turn MOVL of GOT entry into LEAL of symbol address, relative to GOT. s.P[r.Off-2] = 0x8d r.Type = ld.R_GOTOFF return } if r.Off >= 2 && s.P[r.Off-2] == 0xff && s.P[r.Off-1] == 0xb3 { // turn PUSHL of GOT entry into PUSHL of symbol itself. // use unnecessary SS prefix to keep instruction same length. s.P[r.Off-2] = 0x36 s.P[r.Off-1] = 0x68 r.Type = ld.R_ADDR return } ld.Diag("unexpected GOT reloc for non-dynamic symbol %s", targ.Name) return } addgotsym(ld.Ctxt, targ) r.Type = ld.R_CONST // write r->add during relocsym r.Sym = nil r.Add += int64(targ.Got) return case 256 + ld.R_386_GOTOFF: r.Type = ld.R_GOTOFF return case 256 + ld.R_386_GOTPC: r.Type = ld.R_PCREL r.Sym = ld.Linklookup(ld.Ctxt, ".got", 0) r.Add += 4 return case 256 + ld.R_386_32: if targ.Type == ld.SDYNIMPORT { ld.Diag("unexpected R_386_32 relocation for dynamic symbol %s", targ.Name) } r.Type = ld.R_ADDR return case 512 + ld.MACHO_GENERIC_RELOC_VANILLA*2 + 0: r.Type = ld.R_ADDR if targ.Type == ld.SDYNIMPORT { ld.Diag("unexpected reloc for dynamic symbol %s", targ.Name) } return case 512 + ld.MACHO_GENERIC_RELOC_VANILLA*2 + 1: if targ.Type == ld.SDYNIMPORT { addpltsym(ld.Ctxt, targ) r.Sym = ld.Linklookup(ld.Ctxt, ".plt", 0) r.Add = int64(targ.Plt) r.Type = ld.R_PCREL return } r.Type = ld.R_PCREL return case 512 + ld.MACHO_FAKE_GOTPCREL: if targ.Type != ld.SDYNIMPORT { // have symbol // turn MOVL of GOT entry into LEAL of symbol itself if r.Off < 2 || s.P[r.Off-2] != 0x8b { ld.Diag("unexpected GOT reloc for non-dynamic symbol %s", targ.Name) return } s.P[r.Off-2] = 0x8d r.Type = ld.R_PCREL return } addgotsym(ld.Ctxt, targ) r.Sym = ld.Linklookup(ld.Ctxt, ".got", 0) r.Add += int64(targ.Got) r.Type = ld.R_PCREL return } // Handle references to ELF symbols from our own object files. if targ.Type != ld.SDYNIMPORT { return } switch r.Type { case ld.R_CALL, ld.R_PCREL: addpltsym(ld.Ctxt, targ) r.Sym = ld.Linklookup(ld.Ctxt, ".plt", 0) r.Add = int64(targ.Plt) return case ld.R_ADDR: if s.Type != ld.SDATA { break } if ld.Iself { adddynsym(ld.Ctxt, targ) rel := ld.Linklookup(ld.Ctxt, ".rel", 0) ld.Addaddrplus(ld.Ctxt, rel, s, int64(r.Off)) ld.Adduint32(ld.Ctxt, rel, ld.ELF32_R_INFO(uint32(targ.Dynid), ld.R_386_32)) r.Type = ld.R_CONST // write r->add during relocsym r.Sym = nil return } if ld.HEADTYPE == ld.Hdarwin && s.Size == PtrSize && r.Off == 0 { // Mach-O relocations are a royal pain to lay out. // They use a compact stateful bytecode representation // that is too much bother to deal with. // Instead, interpret the C declaration // void *_Cvar_stderr = &stderr; // as making _Cvar_stderr the name of a GOT entry // for stderr. This is separate from the usual GOT entry, // just in case the C code assigns to the variable, // and of course it only works for single pointers, // but we only need to support cgo and that's all it needs. adddynsym(ld.Ctxt, targ) got := ld.Linklookup(ld.Ctxt, ".got", 0) s.Type = got.Type | ld.SSUB s.Outer = got s.Sub = got.Sub got.Sub = s s.Value = got.Size ld.Adduint32(ld.Ctxt, got, 0) ld.Adduint32(ld.Ctxt, ld.Linklookup(ld.Ctxt, ".linkedit.got", 0), uint32(targ.Dynid)) r.Type = 256 // ignore during relocsym return } if ld.HEADTYPE == ld.Hwindows && s.Size == PtrSize { // nothing to do, the relocation will be laid out in pereloc1 return } } ld.Ctxt.Cursym = s ld.Diag("unsupported relocation for dynamic symbol %s (type=%d stype=%d)", targ.Name, r.Type, targ.Type) }
func archreloc(r *ld.Reloc, s *ld.LSym, val *int64) int { if ld.Linkmode == ld.LinkExternal { switch r.Type { default: return -1 case obj.R_ADDRARM64: r.Done = 0 // set up addend for eventual relocation via outer symbol. rs := r.Sym r.Xadd = r.Add for rs.Outer != nil { r.Xadd += ld.Symaddr(rs) - ld.Symaddr(rs.Outer) rs = rs.Outer } if rs.Type != obj.SHOSTOBJ && rs.Sect == nil { ld.Diag("missing section for %s", rs.Name) } r.Xsym = rs // the first instruction is always at the lower address, this is endian neutral; // but note that o0 and o1 should still use the target endian. o0 := ld.Thelinkarch.ByteOrder.Uint32(s.P[r.Off : r.Off+4]) o1 := ld.Thelinkarch.ByteOrder.Uint32(s.P[r.Off+4 : r.Off+8]) // Note: ld64 currently has a bug that any non-zero addend for BR26 relocation // will make the linking fail because it thinks the code is not PIC even though // the BR26 relocation should be fully resolved at link time. // That is the reason why the next if block is disabled. When the bug in ld64 // is fixed, we can enable this block and also enable duff's device in cmd/7g. if false && ld.HEADTYPE == obj.Hdarwin { // Mach-O wants the addend to be encoded in the instruction // Note that although Mach-O supports ARM64_RELOC_ADDEND, it // can only encode 24-bit of signed addend, but the instructions // supports 33-bit of signed addend, so we always encode the // addend in place. o0 |= (uint32((r.Xadd>>12)&3) << 29) | (uint32((r.Xadd>>12>>2)&0x7ffff) << 5) o1 |= uint32(r.Xadd&0xfff) << 10 r.Xadd = 0 } // when laid out, the instruction order must always be o1, o2. if ld.Ctxt.Arch.ByteOrder == binary.BigEndian { *val = int64(o0)<<32 | int64(o1) } else { *val = int64(o1)<<32 | int64(o0) } return 0 case obj.R_CALLARM64: r.Done = 0 r.Xsym = r.Sym *val = int64(0xfc000000 & uint32(r.Add)) r.Xadd = int64((uint32(r.Add) &^ 0xfc000000) * 4) r.Add = 0 return 0 } } switch r.Type { case obj.R_CONST: *val = r.Add return 0 case obj.R_GOTOFF: *val = ld.Symaddr(r.Sym) + r.Add - ld.Symaddr(ld.Linklookup(ld.Ctxt, ".got", 0)) return 0 case obj.R_ADDRARM64: t := ld.Symaddr(r.Sym) + r.Add - ((s.Value + int64(r.Off)) &^ 0xfff) if t >= 1<<32 || t < -1<<32 { ld.Diag("program too large, address relocation distance = %d", t) } // the first instruction is always at the lower address, this is endian neutral; // but note that o0 and o1 should still use the target endian. o0 := ld.Thelinkarch.ByteOrder.Uint32(s.P[r.Off : r.Off+4]) o1 := ld.Thelinkarch.ByteOrder.Uint32(s.P[r.Off+4 : r.Off+8]) o0 |= (uint32((t>>12)&3) << 29) | (uint32((t>>12>>2)&0x7ffff) << 5) o1 |= uint32(t&0xfff) << 10 // when laid out, the instruction order must always be o1, o2. if ld.Ctxt.Arch.ByteOrder == binary.BigEndian { *val = int64(o0)<<32 | int64(o1) } else { *val = int64(o1)<<32 | int64(o0) } return 0 case obj.R_CALLARM64: *val = int64((0xfc000000 & uint32(r.Add)) | uint32((ld.Symaddr(r.Sym)+r.Add*4-(s.Value+int64(r.Off)))/4)) return 0 } return -1 }
func adddynrel(s *ld.LSym, r *ld.Reloc) { targ := r.Sym ld.Ctxt.Cursym = s switch r.Type { default: if r.Type >= 256 { ld.Diag("unexpected relocation type %d", r.Type) return } // Handle relocations found in ELF object files. case 256 + ld.R_ARM_PLT32: r.Type = ld.R_CALLARM if targ.Type == ld.SDYNIMPORT { addpltsym(ld.Ctxt, targ) r.Sym = ld.Linklookup(ld.Ctxt, ".plt", 0) r.Add = int64(braddoff(int32(r.Add), targ.Plt/4)) } return case 256 + ld.R_ARM_THM_PC22: // R_ARM_THM_CALL ld.Diag("R_ARM_THM_CALL, are you using -marm?") ld.Errorexit() return case 256 + ld.R_ARM_GOT32: // R_ARM_GOT_BREL if targ.Type != ld.SDYNIMPORT { addgotsyminternal(ld.Ctxt, targ) } else { addgotsym(ld.Ctxt, targ) } r.Type = ld.R_CONST // write r->add during relocsym r.Sym = nil r.Add += int64(targ.Got) return case 256 + ld.R_ARM_GOT_PREL: // GOT(nil) + A - nil if targ.Type != ld.SDYNIMPORT { addgotsyminternal(ld.Ctxt, targ) } else { addgotsym(ld.Ctxt, targ) } r.Type = ld.R_PCREL r.Sym = ld.Linklookup(ld.Ctxt, ".got", 0) r.Add += int64(targ.Got) + 4 return case 256 + ld.R_ARM_GOTOFF: // R_ARM_GOTOFF32 r.Type = ld.R_GOTOFF return case 256 + ld.R_ARM_GOTPC: // R_ARM_BASE_PREL r.Type = ld.R_PCREL r.Sym = ld.Linklookup(ld.Ctxt, ".got", 0) r.Add += 4 return case 256 + ld.R_ARM_CALL: r.Type = ld.R_CALLARM if targ.Type == ld.SDYNIMPORT { addpltsym(ld.Ctxt, targ) r.Sym = ld.Linklookup(ld.Ctxt, ".plt", 0) r.Add = int64(braddoff(int32(r.Add), targ.Plt/4)) } return case 256 + ld.R_ARM_REL32: // R_ARM_REL32 r.Type = ld.R_PCREL r.Add += 4 return case 256 + ld.R_ARM_ABS32: if targ.Type == ld.SDYNIMPORT { ld.Diag("unexpected R_ARM_ABS32 relocation for dynamic symbol %s", targ.Name) } r.Type = ld.R_ADDR return // we can just ignore this, because we are targeting ARM V5+ anyway case 256 + ld.R_ARM_V4BX: if r.Sym != nil { // R_ARM_V4BX is ABS relocation, so this symbol is a dummy symbol, ignore it r.Sym.Type = 0 } r.Sym = nil return case 256 + ld.R_ARM_PC24, 256 + ld.R_ARM_JUMP24: r.Type = ld.R_CALLARM if targ.Type == ld.SDYNIMPORT { addpltsym(ld.Ctxt, targ) r.Sym = ld.Linklookup(ld.Ctxt, ".plt", 0) r.Add = int64(braddoff(int32(r.Add), targ.Plt/4)) } return } // Handle references to ELF symbols from our own object files. if targ.Type != ld.SDYNIMPORT { return } switch r.Type { case ld.R_CALLARM: addpltsym(ld.Ctxt, targ) r.Sym = ld.Linklookup(ld.Ctxt, ".plt", 0) r.Add = int64(targ.Plt) return case ld.R_ADDR: if s.Type != ld.SDATA { break } if ld.Iself { adddynsym(ld.Ctxt, targ) rel := ld.Linklookup(ld.Ctxt, ".rel", 0) ld.Addaddrplus(ld.Ctxt, rel, s, int64(r.Off)) ld.Adduint32(ld.Ctxt, rel, ld.ELF32_R_INFO(uint32(targ.Dynid), ld.R_ARM_GLOB_DAT)) // we need a nil + A dynmic reloc r.Type = ld.R_CONST // write r->add during relocsym r.Sym = nil return } } ld.Ctxt.Cursym = s ld.Diag("unsupported relocation for dynamic symbol %s (type=%d stype=%d)", targ.Name, r.Type, targ.Type) }
func archinit() { // getgoextlinkenabled is based on GO_EXTLINK_ENABLED when // Go was built; see ../../make.bash. if ld.Linkmode == ld.LinkAuto && obj.Getgoextlinkenabled() == "0" { ld.Linkmode = ld.LinkInternal } switch ld.HEADTYPE { default: if ld.Linkmode == ld.LinkAuto { ld.Linkmode = ld.LinkInternal } if ld.Linkmode == ld.LinkExternal && obj.Getgoextlinkenabled() != "1" { log.Fatalf("cannot use -linkmode=external with -H %s", ld.Headstr(int(ld.HEADTYPE))) } case ld.Hlinux: break } switch ld.HEADTYPE { default: ld.Diag("unknown -H option") ld.Errorexit() fallthrough case ld.Hplan9: /* plan 9 */ ld.HEADR = 32 if ld.INITTEXT == -1 { ld.INITTEXT = 4128 } if ld.INITDAT == -1 { ld.INITDAT = 0 } if ld.INITRND == -1 { ld.INITRND = 4096 } case ld.Hlinux: /* arm64 elf */ ld.Elfinit() ld.HEADR = ld.ELFRESERVE if ld.INITTEXT == -1 { ld.INITTEXT = 0x10000 + int64(ld.HEADR) } if ld.INITDAT == -1 { ld.INITDAT = 0 } if ld.INITRND == -1 { ld.INITRND = 0x10000 } case ld.Hnacl: ld.Elfinit() ld.HEADR = 0x10000 ld.Funcalign = 16 if ld.INITTEXT == -1 { ld.INITTEXT = 0x20000 } if ld.INITDAT == -1 { ld.INITDAT = 0 } if ld.INITRND == -1 { ld.INITRND = 0x10000 } } if ld.INITDAT != 0 && ld.INITRND != 0 { fmt.Printf("warning: -D0x%x is ignored because of -R0x%x\n", uint64(ld.INITDAT), uint32(ld.INITRND)) } }
func archreloc(r *ld.Reloc, s *ld.LSym, val *int64) int { if ld.Linkmode == ld.LinkExternal { switch r.Type { default: return -1 case ld.R_ADDRARM64: r.Done = 0 // the first instruction is always at the lower address, this is endian neutral; // but note that o0 and o1 should still use the target endian. o0 := ld.Thelinkarch.ByteOrder.Uint32(s.P[r.Off : r.Off+4]) o1 := ld.Thelinkarch.ByteOrder.Uint32(s.P[r.Off+4 : r.Off+8]) // when laid out, the instruction order must always be o1, o2. if ld.Ctxt.Arch.ByteOrder == binary.BigEndian { *val = int64(o0)<<32 | int64(o1) } else { *val = int64(o1)<<32 | int64(o0) } // set up addend for eventual relocation via outer symbol. rs := r.Sym r.Xadd = r.Add for rs.Outer != nil { r.Xadd += ld.Symaddr(rs) - ld.Symaddr(rs.Outer) rs = rs.Outer } if rs.Type != ld.SHOSTOBJ && rs.Sect == nil { ld.Diag("missing section for %s", rs.Name) } r.Xsym = rs return 0 case ld.R_CALLARM64: r.Done = 0 r.Xsym = r.Sym *val = int64(0xfc000000 & uint32(r.Add)) r.Xadd = int64((uint32(r.Add) &^ 0xfc000000) * 4) r.Add = 0 return 0 } } switch r.Type { case ld.R_CONST: *val = r.Add return 0 case ld.R_GOTOFF: *val = ld.Symaddr(r.Sym) + r.Add - ld.Symaddr(ld.Linklookup(ld.Ctxt, ".got", 0)) return 0 case ld.R_ADDRARM64: t := ld.Symaddr(r.Sym) + r.Add - ((s.Value + int64(r.Off)) &^ 0xfff) if t >= 1<<32 || t < -1<<32 { ld.Diag("program too large, address relocation distance = %d", t) } // the first instruction is always at the lower address, this is endian neutral; // but note that o0 and o1 should still use the target endian. o0 := ld.Thelinkarch.ByteOrder.Uint32(s.P[r.Off : r.Off+4]) o1 := ld.Thelinkarch.ByteOrder.Uint32(s.P[r.Off+4 : r.Off+8]) o0 |= (uint32((t>>12)&3) << 29) | (uint32((t>>12>>2)&0x7ffff) << 5) o1 |= uint32(t&0xfff) << 10 // when laid out, the instruction order must always be o1, o2. if ld.Ctxt.Arch.ByteOrder == binary.BigEndian { *val = int64(o0)<<32 | int64(o1) } else { *val = int64(o1)<<32 | int64(o0) } return 0 case ld.R_CALLARM64: *val = int64((0xfc000000 & uint32(r.Add)) | uint32((ld.Symaddr(r.Sym)+r.Add*4-(s.Value+int64(r.Off)))/4)) return 0 } return -1 }