1931 lines
68 KiB
C
Vendored
1931 lines
68 KiB
C
Vendored
/* This is a cut-down version of loader.h from cctools-895,
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shrunk to eliminate aspects unwanted in libdwarf and to avoid
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#include entirely. All tab characters replaced with 4 spaces
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so various things no line up as they used to.
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Comment reformatting for line length may have left
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some original comments hard to follow.
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cctools-895 in its original form
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is available from https://opensource.apple.com/
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see Developer Tools version 8.2.1. cctools-895/include/loader.h */
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/*
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* Copyright (c) 1999-2010 Apple Inc. All Rights Reserved.
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*
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* @APPLE_LICENSE_HEADER_START@
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*
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* This file contains Original Code and/or
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* Modifications of Original Code
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* as defined in and that are subject to the
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* Apple Public Source License
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* Version 2.0 (the 'License'). You may not use this file except in
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* compliance with the License. Please obtain a copy of the License at
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* http://www.opensource.apple.com/apsl/ and read it before using this
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* file.
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*
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* The Original Code and all software distributed under
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* the License are
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* distributed on an 'AS IS' basis, WITHOUT
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* WARRANTY OF ANY KIND, EITHER
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* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
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* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
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* FITNESS FOR A PARTICULAR PURPOSE,
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* QUIET ENJOYMENT OR NON-INFRINGEMENT.
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* Please see the License for the
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* specific language governing rights and
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* limitations under the License.
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*
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* @APPLE_LICENSE_HEADER_END@
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*/
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#ifndef MACHO_LOADER_H
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#define MACHO_LOADER_H
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#ifdef __cplusplus
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extern "C" {
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#endif /* __cplusplus */
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#if 0 /* Not used here. DavidA. September 2018 */
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/*
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* This file describes the format of mach object files.
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*/
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#include <stdint.h>
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/*
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* <mach/machine.h> is needed here for
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* the cpu_type_t and cpu_subtype_t types
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* and contains the constants for the possible values of these types.
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*/
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#include <mach/machine.h>
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/*
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* <mach/vm_prot.h> is needed here for the
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* vm_prot_t type and contains the
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* constants that are or'ed together for the
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* possible values of this type.
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*/
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#include <mach/vm_prot.h>
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/*
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* <machine/thread_status.h> is expected to define
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* the flavors of the thread
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* states and the structures of those flavors for each machine.
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*/
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#include <mach/machine/thread_status.h>
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#include <architecture/byte_order.h>
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#endif /* 0 */
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#ifndef TYP
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#define TYP(n,l) char (n)[(l)]
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#endif /* TYP */
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/*
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* The 32-bit mach header appears at the very
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* beginning of the object file for
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* 32-bit architectures.
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*/
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struct mach_header {
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TYP(magic,4); /* mach magic number identifier */
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TYP(cputype,4); /* cpu specifier */
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TYP(cpusubtype,4); /* machine specifier */
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TYP(filetype,4); /* type of file */
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TYP(ncmds,4); /* number of load commands */
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TYP(sizeofcmds,4); /* the size of all the load commands */
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TYP(flags,4); /* flags */
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};
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/* Constant for the magic field of the
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mach_header (32-bit architectures)
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MH_MAGIC MH_MAGIC_64 appear in big-endian objects
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MH_CIGAM MH_CIGAM_64 appear in little-endian objects */
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#define MH_MAGIC 0xfeedface /* the mach magic number */
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#define MH_CIGAM 0xcefaedfe /* NXSwapInt(MH_MAGIC) */
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/*
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* The 64-bit mach header appears at the
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* very beginning of object files for
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* 64-bit architectures.
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*/
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struct mach_header_64 {
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TYP(magic,4); /* mach magic number identifier */
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TYP(cputype,4); /* cpu specifier */
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TYP(cpusubtype,4); /* machine specifier */
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TYP(filetype,4); /* type of file */
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TYP(ncmds,4); /* number of load commands */
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TYP(sizeofcmds,4); /* the size of all the load commands */
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TYP(flags,4); /* flags */
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TYP(reserved,4); /* reserved */
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};
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/* Constant for the magic field of the mach_header_64
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* (64-bit architectures) */
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#define MH_MAGIC_64 0xfeedfacf /* the 64-bit mach magic number */
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#define MH_CIGAM_64 0xcffaedfe /* NXSwapInt(MH_MAGIC_64) */
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/*
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* The layout of the file depends on the filetype.
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* For all but the MH_OBJECT
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* file type the segments are padded
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* out and aligned on a segment alignment
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* boundary for efficient demand paging.
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* The MH_EXECUTE, MH_FVMLIB, MH_DYLIB,
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* MH_DYLINKER and MH_BUNDLE file types also
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* have the headers included as part
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* of their first segment.
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*
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* The file type MH_OBJECT is a compact
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* format intended as output of the
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* assembler and input (and possibly output) of the link editor (the .o
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* format). All sections are in one unnamed
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* segment with no segment padding.
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* This format is used as an executable
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* format when the file is so small the
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* segment padding greatly increases its size.
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*
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* The file type MH_PRELOAD is an executable
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* format intended for things that
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* are not executed under the kernel (proms,
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* stand alones, kernels, etc). The
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* format can be executed under the kernel
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* but may demand paged it and not
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* preload it before execution.
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*
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* A core file is in MH_CORE format and can be
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* in any legal
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* Mach-O file.
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*
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* Constants for the filetype field of the mach_header
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*/
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#define MH_OBJECT 0x1 /* relocatable object file */
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#define MH_EXECUTE 0x2 /* demand paged executable file */
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#define MH_FVMLIB 0x3 /* fixed VM shared library file */
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#define MH_CORE 0x4 /* core file */
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#define MH_PRELOAD 0x5 /* preloaded executable file */
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#define MH_DYLIB 0x6 /* dynamically bound shared library */
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#define MH_DYLINKER 0x7 /* dynamic link editor */
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#define MH_BUNDLE 0x8 /* dynamically bound bundle file */
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#define MH_DYLIB_STUB 0x9 /* shared library stub for static */
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/* linking only, no section contents */
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#define MH_DSYM 0xa /* companion file with only debug */
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/* sections */
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#define MH_KEXT_BUNDLE 0xb /* x86_64 kexts */
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/* Constants for the flags field of the mach_header */
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#define MH_NOUNDEFS 0x1 /* the object file has no undefined
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references */
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#define MH_INCRLINK 0x2 /* the object file is the output of an
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incremental link against a base file
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and can't be link edited again */
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#define MH_DYLDLINK 0x4 /* the object file is input for the
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dynamic linker and can't be staticly
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link edited again */
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#define MH_BINDATLOAD 0x8 /* the object file's undefined
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references are bound by the dynamic
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linker when loaded. */
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#define MH_PREBOUND 0x10 /* the file has its dynamic undefined
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references prebound. */
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#define MH_SPLIT_SEGS 0x20 /* the file has its read-only and
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read-write segments split */
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#define MH_LAZY_INIT 0x40 /* the shared library init routine is
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to be run lazily via catching memory
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faults to its writeable segments
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(obsolete) */
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#define MH_TWOLEVEL 0x80 /* the image is using two-level name
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space bindings */
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#define MH_FORCE_FLAT 0x100 /* the executable is forcing all images
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to use flat name space bindings */
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#define MH_NOMULTIDEFS 0x200 /* this umbrella guarantees no multiple
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definitions of symbols in its
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sub-images so the two-level namespace
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hints can always be used. */
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#define MH_NOFIXPREBINDING 0x400 /* do not have dyld notify the
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prebinding agent about this
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executable */
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#define MH_PREBINDABLE 0x800 /* the binary is not prebound but can
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have its prebinding redone. only used
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when MH_PREBOUND is not set. */
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#define MH_ALLMODSBOUND 0x1000 /* indicates that this binary binds to
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all two-level namespace modules of
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its dependent libraries. only used
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when MH_PREBINDABLE and MH_TWOLEVEL
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are both set. */
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#define MH_SUBSECTIONS_VIA_SYMBOLS 0x2000
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/* safe to divide up the sections into
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sub-sections via symbols for dead
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code stripping */
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#define MH_CANONICAL 0x4000
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/* the binary has been canonicalized
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via the unprebind operation */
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#define MH_WEAK_DEFINES 0x8000
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/* the final linked image contains
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external weak symbols */
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#define MH_BINDS_TO_WEAK 0x10000
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/* the final linked image uses
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weak symbols */
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#define MH_ALLOW_STACK_EXECUTION 0x20000
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/* When this bit is set, all stacks
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in the task will be given stack
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execution privilege. Only used in
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MH_EXECUTE filetypes. */
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#define MH_ROOT_SAFE 0x40000 /* When this bit is set, the binary
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declares it is safe for use in
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processes with uid zero */
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#define MH_SETUID_SAFE 0x80000 /* When this bit is set, the binary
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declares it is safe for use in
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processes when issetugid() is true */
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#define MH_NO_REEXPORTED_DYLIBS 0x100000
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/* When this bit is set on a dylib,
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the static linker does not need to
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examine dependent dylibs to see
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if any are re-exported */
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#define MH_PIE 0x200000 /* When this bit is set, the OS will
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load the main executable at a
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random address. Only used in
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MH_EXECUTE filetypes. */
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#define MH_DEAD_STRIPPABLE_DYLIB 0x400000
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/* Only for use on dylibs. When
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linking against a dylib that
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has this bit set, the static linker
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will automatically not create a
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LC_LOAD_DYLIB load command to the
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dylib if no symbols are being
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referenced from the dylib. */
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#define MH_HAS_TLV_DESCRIPTORS 0x800000
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/* Contains a section of type
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S_THREAD_LOCAL_VARIABLES */
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#define MH_NO_HEAP_EXECUTION 0x1000000 /* When this bit is set,
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the OS will
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run the main executable with
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a non-executable heap even on
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platforms (e.g. i386) that don't
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require it. Only used in MH_EXECUTE
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filetypes. */
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#define MH_APP_EXTENSION_SAFE 0x02000000
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/* The code was linked for use in an
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application extension. */
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/*
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* The load commands directly follow the mach_header.
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* The total size of all
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* of the commands is given by the sizeofcmds
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* field in the mach_header. All
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* load commands must have as their first two
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* fields cmd and cmdsize. The cmd
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* field is filled in with a constant for that command type.
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* Each command type
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* has a structure specifically for it.
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* The cmdsize field is the size in bytes
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* of the particular load command structure
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* plus anything that follows it that
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* is a part of the load command (i.e.
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* section structures, strings, etc.). To
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* advance to the next load command the
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* cmdsize can be added to the offset or
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* pointer of the current load command.
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* The cmdsize for 32-bit architectures
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* MUST be a multiple of 4 bytes and for
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* 64-bit architectures MUST be a multiple
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* of 8 bytes (these are forever the maximum
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* alignment of any load commands).
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* The padded bytes must be zero.
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* All tables in the object file must also
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* follow these rules so the file can be memory mapped.
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* Otherwise the pointers
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* to these tables will not work well or at all
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* on some machines. With all
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|
* padding zeroed like objects will compare byte for byte.
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|
*/
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struct load_command {
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TYP(cmd,4); /* type of load command */
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TYP(cmdsize,4); /* total size of command in bytes */
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};
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/*
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* After MacOS X 10.1 when a new load command
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* is added that is required to be
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* understood by the dynamic linker for the
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* image to execute properly the
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* LC_REQ_DYLD bit will be or'ed into the load
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* command constant. If the dynamic
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* linker sees such a load command it it does
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* not understand will issue a
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* "unknown load command required for execution"
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* error and refuse to use the
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* image. Other load commands without this bit
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* that are not understood will
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* simply be ignored.
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*/
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#define LC_REQ_DYLD 0x80000000
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/* Constants for the cmd field of all load commands, the type */
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#define LC_SEGMENT 0x1 /* segment of this file to be mapped */
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#define LC_SYMTAB 0x2 /* link-edit stab symbol table info */
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#define LC_SYMSEG 0x3 /* link-edit gdb symbol table info (obsolete) */
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#define LC_THREAD 0x4 /* thread */
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#define LC_UNIXTHREAD 0x5 /* unix thread (includes a stack) */
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#define LC_LOADFVMLIB 0x6 /*load a specified fixed VM shared library*/
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#define LC_IDFVMLIB 0x7 /* fixed VM shared library identification */
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#define LC_IDENT 0x8 /* object identification info (obsolete) */
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#define LC_FVMFILE 0x9 /* fixed VM file inclusion (internal use) */
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#define LC_PREPAGE 0xa /* prepage command (internal use) */
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#define LC_DYSYMTAB 0xb
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/* dynamic link-edit symbol table info */
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#define LC_LOAD_DYLIB 0xc
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/* load a dynamically linked shared library */
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#define LC_ID_DYLIB 0xd
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/* dynamically linked shared lib ident */
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#define LC_LOAD_DYLINKER 0xe /* load a dynamic linker */
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#define LC_ID_DYLINKER 0xf
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/* dynamic linker identification */
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#define LC_PREBOUND_DYLIB 0x10
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|
/* modules prebound for a dynamically */
|
|
/* linked shared library */
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#define LC_ROUTINES 0x11 /* image routines */
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#define LC_SUB_FRAMEWORK 0x12 /* sub framework */
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#define LC_SUB_UMBRELLA 0x13 /* sub umbrella */
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#define LC_SUB_CLIENT 0x14 /* sub client */
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|
#define LC_SUB_LIBRARY 0x15 /* sub library */
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|
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#define LC_TWOLEVEL_HINTS 0x16
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|
/* two-level namespace lookup hints */
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#define LC_PREBIND_CKSUM 0x17 /* prebind checksum */
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|
|
/*
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* load a dynamically linked shared library
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* that is allowed to be missing
|
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* (all symbols are weak imported).
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*/
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#define LC_LOAD_WEAK_DYLIB (0x18 | LC_REQ_DYLD)
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#define LC_SEGMENT_64 0x19
|
|
/* 64-bit segment of this file to be
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mapped */
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|
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#define LC_ROUTINES_64 0x1a /* 64-bit image routines */
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|
#define LC_UUID 0x1b /* the uuid */
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|
#define LC_RPATH (0x1c | LC_REQ_DYLD) /* runpath additions */
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|
#define LC_CODE_SIGNATURE 0x1d /* local of code signature */
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|
|
#define LC_SEGMENT_SPLIT_INFO 0x1e
|
|
/* local of info to split segments */
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|
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#define LC_REEXPORT_DYLIB (0x1f | LC_REQ_DYLD)
|
|
/* load and re-export dylib */
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|
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#define LC_LAZY_LOAD_DYLIB 0x20
|
|
/* delay load of dylib until first use */
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|
|
|
#define LC_ENCRYPTION_INFO 0x21
|
|
/* encrypted segment information */
|
|
|
|
#define LC_DYLD_INFO 0x22
|
|
/* compressed dyld information */
|
|
|
|
#define LC_DYLD_INFO_ONLY (0x22|LC_REQ_DYLD)
|
|
/* compressed dyld information only */
|
|
|
|
#define LC_LOAD_UPWARD_DYLIB (0x23 | LC_REQ_DYLD)
|
|
/* load upward dylib */
|
|
|
|
#define LC_VERSION_MIN_MACOSX 0x24
|
|
/* build for MacOSX min OS version */
|
|
|
|
#define LC_VERSION_MIN_IPHONEOS 0x25
|
|
/* build for iPhoneOS min OS version */
|
|
|
|
#define LC_FUNCTION_STARTS 0x26
|
|
/* compressed table of function start addresses */
|
|
|
|
#define LC_DYLD_ENVIRONMENT 0x27
|
|
/* string for dyld to treat
|
|
like environment variable */
|
|
|
|
#define LC_MAIN (0x28|LC_REQ_DYLD)
|
|
/* replacement for LC_UNIXTHREAD */
|
|
|
|
#define LC_DATA_IN_CODE 0x29
|
|
/* table of non-instructions in __text */
|
|
|
|
#define LC_SOURCE_VERSION 0x2A
|
|
/* source version used to build binary */
|
|
|
|
#define LC_DYLIB_CODE_SIGN_DRS 0x2B
|
|
/* Code signing DRs copied from linked dylibs */
|
|
|
|
#define LC_ENCRYPTION_INFO_64 0x2C
|
|
/* 64-bit encrypted segment information */
|
|
|
|
#define LC_LINKER_OPTION 0x2D
|
|
/* linker options in MH_OBJECT files */
|
|
|
|
#define LC_LINKER_OPTIMIZATION_HINT 0x2E
|
|
/* optimization hints in MH_OBJECT files */
|
|
|
|
#define LC_VERSION_MIN_TVOS 0x2F
|
|
/* build for AppleTV min OS version */
|
|
|
|
#define LC_VERSION_MIN_WATCHOS 0x30
|
|
/* build for Watch min OS version */
|
|
|
|
/*
|
|
* A variable length string in a load command
|
|
* is represented by an lc_str
|
|
* union. The strings are stored just after
|
|
* the load command structure and
|
|
* the offset is from the start of the load
|
|
* command structure. The size
|
|
* of the string is reflected in the cmdsize field of the load command.
|
|
* Once again any padded bytes to bring the cmdsize field to a multiple
|
|
* of 4 bytes must be zero.
|
|
*/
|
|
union lc_str {
|
|
TYP(offset,4); /* offset to the string */
|
|
#ifndef __LP64__
|
|
char *ptr; /* pointer to the string */
|
|
#endif
|
|
};
|
|
|
|
/*
|
|
* The segment load command indicates that a part of this file is to be
|
|
* mapped into the task's address space.
|
|
* The size of this segment in memory,
|
|
* vmsize, maybe equal to or larger than the amount
|
|
* to map from this file,
|
|
* filesize. The file is mapped starting at fileoff
|
|
* to the beginning of
|
|
* the segment in memory, vmaddr.
|
|
* The rest of the memory of the segment,
|
|
* if any, is allocated zero fill on demand.
|
|
* The segment's maximum virtual
|
|
* memory protection and initial virtual memory
|
|
* protection are specified
|
|
* by the maxprot and initprot fields.
|
|
* If the segment has sections then the
|
|
* section structures directly follow the segment
|
|
* command and their size is
|
|
* reflected in cmdsize.
|
|
*/
|
|
struct segment_command { /* for 32-bit architectures */
|
|
TYP(cmd,4); /* LC_SEGMENT */
|
|
TYP(cmdsize,4); /* includes sizeof section structs */
|
|
char segname[16]; /* segment name */
|
|
TYP(vmaddr,4); /* memory address of this segment */
|
|
TYP(vmsize,4); /* memory size of this segment */
|
|
TYP(fileoff,4); /* file offset of this segment */
|
|
TYP(filesize,4); /* amount to map from the file */
|
|
TYP(maxprot,4); /* maximum VM protection */
|
|
TYP(initprot,4); /* initial VM protection */
|
|
TYP(nsects,4); /* number of sections in segment */
|
|
TYP(flags,4); /* flags */
|
|
};
|
|
|
|
/*
|
|
* The 64-bit segment load command indicates
|
|
* that a part of this file is to be
|
|
* mapped into a 64-bit task's address space.
|
|
* If the 64-bit segment has
|
|
* sections then section_64 structures directly
|
|
* follow the 64-bit segment
|
|
* command and their size is reflected in cmdsize.
|
|
*/
|
|
struct segment_command_64 { /* for 64-bit architectures */
|
|
TYP(cmd,4); /* LC_SEGMENT_64 */
|
|
TYP(cmdsize,4); /* includes sizeof section_64 structs */
|
|
char segname[16]; /* segment name */
|
|
TYP(vmaddr,8); /* memory address of this segment */
|
|
TYP(vmsize,8); /* memory size of this segment */
|
|
TYP(fileoff,8); /* file offset of this segment */
|
|
TYP(filesize,8); /* amount to map from the file */
|
|
TYP(maxprot,4); /* maximum VM protection */
|
|
TYP(initprot,4); /* initial VM protection */
|
|
TYP(nsects,4); /* number of sections in segment */
|
|
TYP(flags,4); /* flags */
|
|
};
|
|
|
|
/* Constants for the flags field of the segment_command */
|
|
#define SG_HIGHVM 0x1
|
|
/* the file contents for this segment is for
|
|
the high part of the VM space, the low part
|
|
is zero filled (for stacks in core files) */
|
|
#define SG_FVMLIB 0x2
|
|
/* this segment is the VM that is allocated by
|
|
a fixed VM library, for overlap checking in
|
|
the link editor */
|
|
#define SG_NORELOC 0x4
|
|
/* this segment has nothing that was relocated
|
|
in it and nothing relocated to it, that is
|
|
it maybe safely replaced without relocation*/
|
|
#define SG_PROTECTED_VERSION_1 0x8
|
|
/* This segment is protected. If the
|
|
segment starts at file offset 0, the
|
|
first page of the segment is not
|
|
protected. All other pages of the
|
|
segment are protected. */
|
|
|
|
/*
|
|
* A segment is made up of zero or more sections.
|
|
* Non-MH_OBJECT files have
|
|
* all of their segments with the proper sections
|
|
* in each, and padded to the
|
|
* specified segment alignment when produced by
|
|
* the link editor. The first
|
|
* segment of a MH_EXECUTE and MH_FVMLIB format file
|
|
* contains the mach_header
|
|
* and load commands of the object file before its
|
|
* first section. The zero
|
|
* fill sections are always last in their segment
|
|
* (in all formats). This
|
|
* allows the zeroed segment padding to be mapped
|
|
* into memory where zero fill
|
|
* sections might be. The gigabyte zero fill sections,
|
|
* those with the section
|
|
* type S_GB_ZEROFILL, can only be in a segment
|
|
* with sections of this type.
|
|
* These segments are then placed after all other segments.
|
|
*
|
|
* The MH_OBJECT format has all of its sections in one segment for
|
|
* compactness. There is no padding to a specified
|
|
* segment boundary and the
|
|
* mach_header and load commands are not part of the segment.
|
|
*
|
|
* Sections with the same section name, sectname,
|
|
* going into the same segment,
|
|
* segname, are combined by the link editor.
|
|
* The resulting section is aligned
|
|
* to the maximum alignment of the combined sections
|
|
* and is the new section's
|
|
* alignment. The combined sections are aligned to
|
|
* their original alignment in
|
|
* the combined section. Any padded bytes to get
|
|
* the specified alignment are
|
|
* zeroed.
|
|
*
|
|
* The format of the relocation entries referenced by
|
|
* the reloff and nreloc
|
|
* fields of the section structure for mach
|
|
* object files is described in the
|
|
* header file <reloc.h>.
|
|
*/
|
|
struct section { /* for 32-bit architectures */
|
|
char sectname[16]; /* name of this section */
|
|
char segname[16]; /* segment this section goes in */
|
|
TYP(addr,4); /* memory address of this section */
|
|
TYP(size,4); /* size in bytes of this section */
|
|
TYP(offset,4); /* file offset of this section */
|
|
TYP(align,4); /* section alignment (power of 2) */
|
|
TYP(reloff,4); /* file offset of relocation entries */
|
|
TYP(nreloc,4); /* number of relocation entries */
|
|
TYP(flags,4); /* flags (section type and attributes)*/
|
|
TYP(reserved1,4); /* reserved (for offset or index) */
|
|
TYP(reserved2,4); /* reserved (for count or sizeof) */
|
|
};
|
|
|
|
struct section_64 { /* for 64-bit architectures */
|
|
char sectname[16]; /* name of this section */
|
|
char segname[16]; /* segment this section goes in */
|
|
TYP(addr,8); /* memory address of this section */
|
|
TYP(size,8); /* size in bytes of this section */
|
|
TYP(offset,4); /* file offset of this section */
|
|
TYP(align,4); /* section alignment (power of 2) */
|
|
TYP(reloff,4); /* file offset of relocation entries */
|
|
TYP(nreloc,4); /* number of relocation entries */
|
|
TYP(flags,4); /* flags (section type and attributes)*/
|
|
TYP(reserved1,4); /* reserved (for offset or index) */
|
|
TYP(reserved2,4); /* reserved (for count or sizeof) */
|
|
TYP(reserved3,4); /* reserved */
|
|
};
|
|
|
|
/*
|
|
* The flags field of a section structure is
|
|
* separated into two parts a section
|
|
* type and section attributes.
|
|
* The section types are mutually exclusive (it
|
|
* can only have one type) but the section attributes
|
|
* are not (it may have more
|
|
* than one attribute).
|
|
*/
|
|
#define SECTION_TYPE 0x000000ff /* 256 section types */
|
|
|
|
#define SECTION_ATTRIBUTES 0xffffff00
|
|
/* 24 section attributes */
|
|
|
|
/* Constants for the type of a section */
|
|
#define S_REGULAR 0x0 /* regular section */
|
|
#define S_ZEROFILL 0x1 /* zero fill on demand section */
|
|
|
|
#define S_CSTRING_LITERALS 0x2
|
|
/* section with only literal C strings*/
|
|
|
|
#define S_4BYTE_LITERALS 0x3
|
|
/* section with only 4 byte literals */
|
|
|
|
#define S_8BYTE_LITERALS 0x4
|
|
/* section with only 8 byte literals */
|
|
|
|
#define S_LITERAL_POINTERS 0x5
|
|
/* section with only pointers to */
|
|
/* literals */
|
|
/*
|
|
* For the two types of symbol pointers
|
|
* sections and the symbol stubs section
|
|
* they have indirect symbol table entries.
|
|
* For each of the entries in the
|
|
* section the indirect symbol table entries,
|
|
* in corresponding order in the
|
|
* indirect symbol table, start at the
|
|
* index stored in the reserved1 field
|
|
* of the section structure. Since the indirect symbol table entries
|
|
* correspond to the entries in the section
|
|
* the number of indirect symbol table
|
|
* entries is inferred from the size of the
|
|
* section divided by the size of the
|
|
* entries in the section.
|
|
* For symbol pointers sections the size of the entries
|
|
* in the section is 4 bytes and for symbol stubs
|
|
* sections the byte size of the
|
|
* stubs is stored in the reserved2 field of the section structure.
|
|
*/
|
|
#define S_NON_LAZY_SYMBOL_POINTERS 0x6
|
|
/* section with only non-lazy
|
|
symbol pointers */
|
|
#define S_LAZY_SYMBOL_POINTERS 0x7
|
|
/* section with only lazy symbol
|
|
pointers */
|
|
#define S_SYMBOL_STUBS 0x8
|
|
/* section with only symbol
|
|
stubs, byte size of stub in
|
|
the reserved2 field */
|
|
#define S_MOD_INIT_FUNC_POINTERS 0x9
|
|
/* section with only function
|
|
pointers for initialization*/
|
|
#define S_MOD_TERM_FUNC_POINTERS 0xa
|
|
/* section with only function
|
|
pointers for termination */
|
|
#define S_COALESCED 0xb
|
|
/* section contains symbols that
|
|
are to be coalesced */
|
|
#define S_GB_ZEROFILL 0xc
|
|
/* zero fill on demand section
|
|
(that can be larger than 4
|
|
gigabytes) */
|
|
#define S_INTERPOSING 0xd
|
|
/* section with only pairs of
|
|
function pointers for
|
|
interposing */
|
|
#define S_16BYTE_LITERALS 0xe
|
|
/* section with only 16 byte
|
|
literals */
|
|
#define S_DTRACE_DOF 0xf
|
|
/* section contains
|
|
DTrace Object Format */
|
|
#define S_LAZY_DYLIB_SYMBOL_POINTERS 0x10
|
|
/* section with only lazy
|
|
symbol pointers to lazy
|
|
loaded dylibs */
|
|
/*
|
|
* Section types to support thread local variables
|
|
*/
|
|
#define S_THREAD_LOCAL_REGULAR 0x11
|
|
/* template of initial
|
|
values for TLVs */
|
|
#define S_THREAD_LOCAL_ZEROFILL 0x12
|
|
/* template of initial
|
|
values for TLVs */
|
|
#define S_THREAD_LOCAL_VARIABLES 0x13
|
|
/* TLV descriptors */
|
|
#define S_THREAD_LOCAL_VARIABLE_POINTERS 0x14
|
|
/* pointers to TLV
|
|
descriptors */
|
|
#define S_THREAD_LOCAL_INIT_FUNCTION_POINTERS 0x15
|
|
/* functions to call
|
|
to initialize TLV
|
|
values */
|
|
|
|
/*
|
|
* Constants for the section attributes part of the
|
|
* flags field of a section
|
|
* structure.
|
|
*/
|
|
#define SECTION_ATTRIBUTES_USR 0xff000000
|
|
/* User setable attributes */
|
|
#define S_ATTR_PURE_INSTRUCTIONS 0x80000000
|
|
/* section contains only true
|
|
machine instructions */
|
|
#define S_ATTR_NO_TOC 0x40000000
|
|
/* section contains coalesced
|
|
symbols that are not to be
|
|
in a ranlib table of
|
|
contents */
|
|
#define S_ATTR_STRIP_STATIC_SYMS 0x20000000
|
|
/* ok to strip static symbols
|
|
in this section in files
|
|
with the MH_DYLDLINK flag */
|
|
#define S_ATTR_NO_DEAD_STRIP 0x10000000 /* no dead stripping */
|
|
|
|
#define S_ATTR_LIVE_SUPPORT 0x08000000
|
|
/* blocks are live if they
|
|
reference live blocks */
|
|
|
|
#define S_ATTR_SELF_MODIFYING_CODE 0x04000000
|
|
/* Used with i386 code stubs
|
|
written on by dyld */
|
|
/*
|
|
* If a segment contains any sections marked with S_ATTR_DEBUG then all
|
|
* sections in that segment must have this attribute.
|
|
* No section other than
|
|
* a section marked with this attribute may reference
|
|
* the contents of this
|
|
* section. A section with this attribute may
|
|
* contain no symbols and must have
|
|
* a section type S_REGULAR.
|
|
* The static linker will not copy section contents
|
|
* from sections with this attribute into its output file.
|
|
* These sections
|
|
* generally contain DWARF debugging info.
|
|
*/
|
|
#define S_ATTR_DEBUG 0x02000000 /* a debug section */
|
|
|
|
#define SECTION_ATTRIBUTES_SYS 0x00ffff00
|
|
/* system setable attributes */
|
|
|
|
#define S_ATTR_SOME_INSTRUCTIONS 0x00000400
|
|
/* section contains some
|
|
machine instructions */
|
|
|
|
#define S_ATTR_EXT_RELOC 0x00000200 /* section has external
|
|
relocation entries */
|
|
#define S_ATTR_LOC_RELOC 0x00000100 /* section has local
|
|
relocation entries */
|
|
|
|
/*
|
|
* The names of segments and sections in them are
|
|
* mostly meaningless to the
|
|
* link-editor. But there are few things to support traditional UNIX
|
|
* executables that require the link-editor and assembler
|
|
* to use some names
|
|
* agreed upon by convention.
|
|
*
|
|
* The initial protection of the "__TEXT" segment
|
|
* has write protection turned
|
|
* off (not writeable).
|
|
*
|
|
* The link-editor will allocate common symbols at
|
|
* the end of the "__common"
|
|
* section in the "__DATA" segment.
|
|
* It will create the section and segment
|
|
* if needed.
|
|
*/
|
|
|
|
/* The currently known segment names and the
|
|
* section names in those segments */
|
|
|
|
#define SEG_PAGEZERO "__PAGEZERO"
|
|
/* the pagezero segment which has no */
|
|
/* protections and catches NULL */
|
|
/* references for MH_EXECUTE files */
|
|
|
|
#define SEG_TEXT "__TEXT" /* the tradition UNIX text segment */
|
|
#define SECT_TEXT "__text"
|
|
/* the real text part of the text */
|
|
/* section no headers, and no padding */
|
|
|
|
#define SECT_FVMLIB_INIT0 "__fvmlib_init0"
|
|
/* the fvmlib initialization */
|
|
/* section */
|
|
|
|
#define SECT_FVMLIB_INIT1 "__fvmlib_init1"
|
|
/* the section following the */
|
|
/* fvmlib initialization */
|
|
/* section */
|
|
|
|
#define SEG_DATA "__DATA" /* the tradition UNIX data segment */
|
|
#define SECT_DATA "__data" /* the real initialized data section */
|
|
/* no padding, no bss overlap */
|
|
#define SECT_BSS "__bss" /* the real uninitialized data section*/
|
|
/* no padding */
|
|
#define SECT_COMMON "__common"
|
|
/* the section common symbols are */
|
|
/* allocated in by the link editor */
|
|
|
|
#define SEG_OBJC "__OBJC" /* objective-C runtime segment */
|
|
#define SECT_OBJC_SYMBOLS "__symbol_table" /* symbol table */
|
|
#define SECT_OBJC_MODULES "__module_info" /* module information */
|
|
#define SECT_OBJC_STRINGS "__selector_strs" /* string table */
|
|
#define SECT_OBJC_REFS "__selector_refs" /* string table */
|
|
|
|
#define SEG_ICON "__ICON" /* the icon segment */
|
|
#define SECT_ICON_HEADER "__header" /* the icon headers */
|
|
#define SECT_ICON_TIFF "__tiff" /* the icons in tiff format */
|
|
|
|
#define SEG_LINKEDIT "__LINKEDIT"
|
|
/* the segment containing all structs */
|
|
/* created and maintained by the link */
|
|
/* editor. Created with -seglinkedit */
|
|
/* option to ld(1) for MH_EXECUTE and */
|
|
/* FVMLIB file types only */
|
|
|
|
#define SEG_UNIXSTACK "__UNIXSTACK" /* the unix stack segment */
|
|
|
|
#define SEG_IMPORT "__IMPORT" /* the segment for the self (dyld) */
|
|
/* modifing code stubs that has read, */
|
|
/* write and execute permissions */
|
|
|
|
/*
|
|
* Fixed virtual memory shared libraries are
|
|
* identified by two things. The
|
|
* target pathname (the name of the library
|
|
* as found for execution), and the
|
|
* minor version number.
|
|
* The address of where the headers are loaded is in
|
|
* header_addr. (THIS IS OBSOLETE and no longer supported).
|
|
*/
|
|
struct fvmlib {
|
|
union lc_str name; /* library's target pathname */
|
|
TYP(minor_version,4); /* library's minor version number */
|
|
TYP(header_addr,4); /* library's header address */
|
|
};
|
|
|
|
/*
|
|
* A fixed virtual shared library (filetype == MH_FVMLIB
|
|
* in the mach header)
|
|
* contains a fvmlib_command (cmd == LC_IDFVMLIB) to
|
|
* identify the library.
|
|
* An object that uses a fixed virtual shared library also contains a
|
|
* fvmlib_command (cmd == LC_LOADFVMLIB) for each library it uses.
|
|
* (THIS IS OBSOLETE and no longer supported).
|
|
*/
|
|
struct fvmlib_command {
|
|
TYP(cmd,4); /* LC_IDFVMLIB or LC_LOADFVMLIB */
|
|
TYP(cmdsize,4); /* includes pathname string */
|
|
struct fvmlib fvmlib; /* the library identification */
|
|
};
|
|
|
|
/*
|
|
* Dynamicly linked shared libraries are identified by two things. The
|
|
* pathname (the name of the library as found for execution), and the
|
|
* compatibility version number. The pathname must match
|
|
* and the compatibility
|
|
* number in the user of the library must be greater than or
|
|
* equal to the
|
|
* library being used. The time stamp is used to record the
|
|
* time a library was
|
|
* built and copied into user so it can be use to determined
|
|
* if the library used
|
|
* at runtime is exactly the same as used to built the program.
|
|
*/
|
|
struct dylib {
|
|
union lc_str name; /* library's path name */
|
|
TYP(timestamp,4); /* library's build time stamp */
|
|
TYP(current_version,4); /* library's current version number */
|
|
|
|
TYP(compatibility_version,4);
|
|
/* library's compatibility vers number*/
|
|
};
|
|
|
|
/*
|
|
* A dynamically linked shared library (filetype == MH_DYLIB
|
|
* in the mach header)
|
|
* contains a dylib_command (cmd == LC_ID_DYLIB) to
|
|
* identify the library.
|
|
* An object that uses a dynamically linked shared library
|
|
* also contains a
|
|
* dylib_command (cmd == LC_LOAD_DYLIB, LC_LOAD_WEAK_DYLIB, or
|
|
* LC_REEXPORT_DYLIB) for each library it uses.
|
|
*/
|
|
struct dylib_command {
|
|
TYP(cmd,4); /* LC_ID_DYLIB, LC_LOAD_{,WEAK_}DYLIB,
|
|
LC_REEXPORT_DYLIB */
|
|
TYP(cmdsize,4); /* includes pathname string */
|
|
struct dylib dylib; /* the library identification */
|
|
};
|
|
|
|
/*
|
|
* A dynamically linked shared library may be a
|
|
* subframework of an umbrella
|
|
* framework. If so it will be linked with "-umbrella
|
|
* umbrella_name" where
|
|
* Where "umbrella_name" is the name of the umbrella framework.
|
|
* A subframework
|
|
* can only be linked against by its umbrella framework
|
|
* or other subframeworks
|
|
* that are part of the same umbrella framework.
|
|
* Otherwise the static link
|
|
* editor produces an error and states to link against
|
|
* the umbrella framework.
|
|
* The name of the umbrella framework for subframeworks
|
|
* is recorded in the
|
|
* following structure.
|
|
*/
|
|
struct sub_framework_command {
|
|
TYP(cmd,4); /* LC_SUB_FRAMEWORK */
|
|
TYP(cmdsize,4); /* includes umbrella string */
|
|
union lc_str umbrella; /* the umbrella framework name */
|
|
};
|
|
|
|
/*
|
|
* For dynamically linked shared libraries that
|
|
* are subframework of an umbrella
|
|
* framework they can allow clients other than
|
|
* the umbrella framework or other
|
|
* subframeworks in the same umbrella framework.
|
|
* To do this the subframework
|
|
* is built with "-allowable_client client_name"
|
|
* and an LC_SUB_CLIENT load
|
|
* command is created for each -allowable_client flag.
|
|
* The client_name is
|
|
* usually a framework name.
|
|
* It can also be a name used for bundles clients
|
|
* where the bundle is built with "-client_name client_name".
|
|
*/
|
|
struct sub_client_command {
|
|
TYP(cmd,4); /* LC_SUB_CLIENT */
|
|
TYP(cmdsize,4); /* includes client string */
|
|
union lc_str client; /* the client name */
|
|
};
|
|
|
|
/*
|
|
* A dynamically linked shared library may be a
|
|
* sub_umbrella of an umbrella
|
|
* framework. If so it will be linked with
|
|
* "-sub_umbrella umbrella_name" where
|
|
* Where "umbrella_name" is the name of the
|
|
* sub_umbrella framework. When
|
|
* staticly linking when -twolevel_namespace is
|
|
* in effect a twolevel namespace
|
|
* umbrella framework will only cause its subframeworks
|
|
* and those frameworks
|
|
* listed as sub_umbrella frameworks to be
|
|
* implicited linked in. Any other
|
|
* dependent dynamic libraries will not be linked
|
|
* it when -twolevel_namespace
|
|
* is in effect. The primary library recorded
|
|
* by the static linker when
|
|
* resolving a symbol in these libraries will
|
|
* be the umbrella framework.
|
|
* Zero or more sub_umbrella frameworks may be
|
|
* use by an umbrella framework.
|
|
* The name of a sub_umbrella framework is
|
|
* recorded in the following structure.
|
|
*/
|
|
struct sub_umbrella_command {
|
|
TYP(cmd,4); /* LC_SUB_UMBRELLA */
|
|
TYP(cmdsize,4); /* includes sub_umbrella string */
|
|
union lc_str sub_umbrella; /* the sub_umbrella framework name */
|
|
};
|
|
|
|
/*
|
|
* A dynamically linked shared library may be a
|
|
* sub_library of another shared
|
|
* library. If so it will be linked with
|
|
* "-sub_library library_name" where
|
|
* Where "library_name" is the name of the
|
|
* sub_library shared library. When
|
|
* staticly linking when -twolevel_namespace is in
|
|
* effect a twolevel namespace
|
|
* shared library will only cause its subframeworks
|
|
* and those frameworks
|
|
* listed as sub_umbrella frameworks and libraries
|
|
* listed as sub_libraries to
|
|
* be implicited linked in. Any other dependent
|
|
* dynamic libraries will not be
|
|
* linked it when -twolevel_namespace is in effect.
|
|
* The primary library
|
|
* recorded by the static linker when resolving a
|
|
* symbol in these libraries
|
|
* will be the umbrella framework (or dynamic library).
|
|
* Zero or more sub_library
|
|
* shared libraries may be use by an umbrella framework
|
|
* or (or dynamic library).
|
|
* The name of a sub_library framework is recorded
|
|
* in the following structure.
|
|
* For example /usr/lib/libobjc_profile.A.dylib
|
|
* would be recorded as "libobjc".
|
|
*/
|
|
struct sub_library_command {
|
|
TYP(cmd,4); /* LC_SUB_LIBRARY */
|
|
TYP(cmdsize,4); /* includes sub_library string */
|
|
union lc_str sub_library; /* the sub_library name */
|
|
};
|
|
|
|
/*
|
|
* A program (filetype == MH_EXECUTE) that is
|
|
* prebound to its dynamic libraries has one of
|
|
* these for each library that
|
|
* the static linker used in prebinding.
|
|
* It contains a bit vector for the
|
|
* modules in the library.
|
|
* The bits indicate which modules are bound (1) and
|
|
* which are not (0) from the library.
|
|
* The bit for module 0 is the low bit
|
|
* of the first byte. So the bit for the Nth module is:
|
|
* (linked_modules[N/8] >> N%8) & 1
|
|
*/
|
|
struct prebound_dylib_command {
|
|
TYP(cmd,4); /* LC_PREBOUND_DYLIB */
|
|
TYP(cmdsize,4); /* includes strings */
|
|
union lc_str name; /* library's path name */
|
|
TYP(nmodules,4); /* number of modules in library */
|
|
union lc_str linked_modules; /* bit vector of linked modules */
|
|
};
|
|
|
|
/*
|
|
* A program that uses a dynamic linker contains a
|
|
* dylinker_command to identify
|
|
* the name of the dynamic linker (LC_LOAD_DYLINKER).
|
|
* And a dynamic linker
|
|
* contains a dylinker_command to identify the dynamic
|
|
* linker (LC_ID_DYLINKER).
|
|
* A file can have at most one of these.
|
|
* This struct is also used for the
|
|
* LC_DYLD_ENVIRONMENT load command and
|
|
* contains string for dyld to treat like environment variable.
|
|
*/
|
|
struct dylinker_command {
|
|
TYP(cmd,4); /* LC_ID_DYLINKER, LC_LOAD_DYLINKER or
|
|
LC_DYLD_ENVIRONMENT */
|
|
TYP(cmdsize,4); /* includes pathname string */
|
|
union lc_str name; /* dynamic linker's path name */
|
|
};
|
|
|
|
/*
|
|
* Thread commands contain machine-specific
|
|
* data structures suitable for
|
|
* use in the thread state primitives.
|
|
* The machine specific data structures
|
|
* follow the struct thread_command as follows.
|
|
* Each flavor of machine specific data structure
|
|
* is preceded by an unsigned
|
|
* long constant for the flavor of that data structure, an uint32_t
|
|
* that is the count of longs of the size of the state
|
|
* data structure and then
|
|
* the state data structure follows. This triple may be
|
|
* repeated for many
|
|
* flavors. The constants for the flavors, counts and
|
|
* state data structure
|
|
* definitions are expected to be in the header file
|
|
* <machine/thread_status.h>.
|
|
* These machine specific data structures sizes must be multiples of
|
|
* 4 bytes The cmdsize reflects the total size of the thread_command
|
|
* and all of the sizes of the constants for the flavors,
|
|
* counts and state
|
|
* data structures.
|
|
*
|
|
* For executable objects that are unix processes there will be one
|
|
* thread_command (cmd == LC_UNIXTHREAD) created for it
|
|
* by the link-editor.
|
|
* This is the same as a LC_THREAD, except that a stack
|
|
* is automatically
|
|
* created (based on the shell's limit for the stack size).
|
|
* Command arguments
|
|
* and environment variables are copied onto that stack.
|
|
*/
|
|
struct thread_command {
|
|
TYP(cmd,4); /* LC_THREAD or LC_UNIXTHREAD */
|
|
TYP(cmdsize,4); /* total size of this command */
|
|
/* uint32_t flavor flavor of thread state */
|
|
/* uint32_t count count of longs in thread state */
|
|
/* struct XXX_thread_state state thread state for this flavor */
|
|
/* ... */
|
|
};
|
|
|
|
/*
|
|
* The routines command contains the address of the
|
|
* dynamic shared library
|
|
* initialization routine and an index into the module
|
|
* table for the module
|
|
* that defines the routine. Before any modules are
|
|
* used from the library the
|
|
* dynamic linker fully binds the module that defines
|
|
* the initialization routine
|
|
* and then calls it. This gets called before any
|
|
* module initialization
|
|
* routines (used for C++ static constructors) in the library.
|
|
*/
|
|
struct routines_command { /* for 32-bit architectures */
|
|
TYP(cmd,4); /* LC_ROUTINES */
|
|
TYP(cmdsize,4); /* total size of this command */
|
|
TYP(init_address,4); /* address of initialization routine */
|
|
TYP(init_module,4); /* index into the module table that */
|
|
/* the init routine is defined in */
|
|
TYP(reserved1,4);
|
|
TYP(reserved2,4);
|
|
TYP(reserved3,4);
|
|
TYP(reserved4,4);
|
|
TYP(reserved5,4);
|
|
TYP(reserved6,4);
|
|
};
|
|
|
|
/*
|
|
* The 64-bit routines command. Same use as above.
|
|
*/
|
|
struct routines_command_64 { /* for 64-bit architectures */
|
|
TYP(cmd,4); /* LC_ROUTINES_64 */
|
|
TYP(cmdsize,4); /* total size of this command */
|
|
TYP(init_address,8); /* address of initialization routine */
|
|
TYP(init_module,8); /* index into the module table that */
|
|
/* the init routine is defined in */
|
|
TYP(reserved1,8);
|
|
TYP(reserved2,8);
|
|
TYP(reserved3,8);
|
|
TYP(reserved4,8);
|
|
TYP(reserved5,8);
|
|
TYP(reserved6,8);
|
|
};
|
|
|
|
/*
|
|
* The symtab_command contains the offsets and sizes
|
|
* of the link-edit 4.3BSD
|
|
* "stab" style symbol table information as described
|
|
* in the header files
|
|
* <nlist.h> and <stab.h>.
|
|
*/
|
|
struct symtab_command {
|
|
TYP(cmd,4); /* LC_SYMTAB */
|
|
TYP(cmdsize,4); /* sizeof(struct symtab_command) */
|
|
TYP(symoff,4); /* symbol table offset */
|
|
TYP(nsyms,4); /* number of symbol table entries */
|
|
TYP(stroff,4); /* string table offset */
|
|
TYP(strsize,4); /* string table size in bytes */
|
|
};
|
|
|
|
/*
|
|
* This is the second set of the symbolic information
|
|
* which is used to support
|
|
* the data structures for the dynamically link editor.
|
|
*
|
|
* The original set of symbolic information in the
|
|
* symtab_command which contains
|
|
* the symbol and string tables must also be present
|
|
* when this load command is
|
|
* present. When this load command is present the symbol
|
|
* table is organized
|
|
* into three groups of symbols:
|
|
* local symbols (static and debugging symbols) - grouped by module
|
|
* defined external symbols - grouped by module
|
|
* (sorted by name if not lib)
|
|
* undefined external symbols
|
|
* (sorted by name if MH_BINDATLOAD is not set,
|
|
* and in order the were seen by the static
|
|
* linker if MH_BINDATLOAD is set)
|
|
* In this load command there are offsets
|
|
* and counts to each of the three groups
|
|
* of symbols.
|
|
*
|
|
* This load command contains a the offsets
|
|
* and sizes of the following new
|
|
* symbolic information tables:
|
|
* table of contents
|
|
* module table
|
|
* reference symbol table
|
|
* indirect symbol table
|
|
* The first three tables above (the table of contents,
|
|
* module table and
|
|
* reference symbol table) are only present if the
|
|
* file is a dynamically linked
|
|
* shared library. For executable and object modules, which are files
|
|
* containing only one module, the information that
|
|
* would be in these three
|
|
* tables is determined as follows:
|
|
* table of contents - the defined external symbols
|
|
* are sorted by name
|
|
* module table - the file contains only one module
|
|
* so everything in the file is part of the module.
|
|
* reference symbol table - is the defined and
|
|
* undefined external symbols
|
|
*
|
|
* For dynamically linked shared library files this
|
|
* load command also contains
|
|
* offsets and sizes to the pool of relocation entries for all sections
|
|
* separated into two groups:
|
|
* external relocation entries
|
|
* local relocation entries
|
|
* For executable and object modules the
|
|
* relocation entries continue to hang
|
|
* off the section structures.
|
|
*/
|
|
struct dysymtab_command {
|
|
TYP(cmd,4); /* LC_DYSYMTAB */
|
|
TYP(cmdsize,4); /* sizeof(struct dysymtab_command) */
|
|
|
|
/*
|
|
* The symbols indicated by symoff and nsyms
|
|
* of the LC_SYMTAB load command
|
|
* are grouped into the following three groups:
|
|
* local symbols (further grouped by the module they are from)
|
|
* defined external symbols (further grouped
|
|
* by the module they are from)
|
|
* undefined symbols
|
|
*
|
|
* The local symbols are used only for debugging.
|
|
* The dynamic binding
|
|
* process may have to use them to indicate to the
|
|
* debugger the local
|
|
* symbols for a module that is being bound.
|
|
*
|
|
* The last two groups are used by the dynamic
|
|
* binding process to do the
|
|
* binding (indirectly through the module table
|
|
* and the reference symbol
|
|
* table when this is a dynamically linked shared library file).
|
|
*/
|
|
TYP(ilocalsym,4); /* index to local symbols */
|
|
TYP(nlocalsym,4); /* number of local symbols */
|
|
|
|
TYP(iextdefsym,4); /* index to externally defined symbols */
|
|
TYP(nextdefsym,4); /* number of externally defined symbols */
|
|
|
|
TYP(iundefsym,4); /* index to undefined symbols */
|
|
TYP(nundefsym,4); /* number of undefined symbols */
|
|
|
|
/*
|
|
* For the for the dynamic binding process to
|
|
* find which module a symbol
|
|
* is defined in the table of contents is used
|
|
* (analogous to the ranlib
|
|
* structure in an archive) which maps defined
|
|
* external symbols to modules
|
|
* they are defined in. This exists only in a
|
|
* dynamically linked shared
|
|
* library file. For executable and object modules
|
|
* the defined external
|
|
* symbols are sorted by name and is use as the table of contents.
|
|
*/
|
|
TYP(tocoff,4); /* file offset to table of contents */
|
|
TYP(ntoc,4); /* number of entries in table of contents */
|
|
|
|
/*
|
|
* To support dynamic binding of "modules" (whole
|
|
* object files) the symbol
|
|
* table must reflect the modules that the file was
|
|
* created from. This is
|
|
* done by having a module table that has indexes
|
|
* and counts into the merged
|
|
* tables for each module.
|
|
* The module structure that these two entries
|
|
* refer to is described below.
|
|
* This exists only in a dynamically linked
|
|
* shared library file. For executable and object
|
|
* modules the file only
|
|
* contains one module so everything in the file belongs
|
|
* to the module.
|
|
*/
|
|
TYP(modtaboff,4); /* file offset to module table */
|
|
TYP(nmodtab,4); /* number of module table entries */
|
|
|
|
/*
|
|
* To support dynamic module binding the module structure
|
|
* for each module
|
|
* indicates the external references (defined and undefined)
|
|
* each module
|
|
* makes. For each module there is an offset and a count into the
|
|
* reference symbol table for the symbols that the module
|
|
* references.
|
|
* This exists only in a dynamically linked shared
|
|
* library file. For
|
|
* executable and object modules the defined external
|
|
* symbols and the
|
|
* undefined external symbols indicates the external references.
|
|
*/
|
|
TYP(extrefsymoff,4); /* offset to referenced symbol table */
|
|
TYP(nextrefsyms,4);/* number of referenced symbol table entries */
|
|
|
|
/*
|
|
* The sections that contain "symbol pointers" and
|
|
* "routine stubs" have
|
|
* indexes and (implied counts based on the size of
|
|
* the section and fixed
|
|
* size of the entry) into the "indirect symbol" table
|
|
* for each pointer
|
|
* and stub. For every section of these two types the
|
|
* index into the
|
|
* indirect symbol table is stored in the section header
|
|
* in the field
|
|
* reserved1. An indirect symbol table entry is simply
|
|
* a 32bit index into
|
|
* the symbol table to the symbol that the pointer or
|
|
* stub is referring to.
|
|
* The indirect symbol table is ordered to match the
|
|
* entries in the section.
|
|
*/
|
|
TYP(indirectsymoff,4);
|
|
/* file offset to the indirect symbol table */
|
|
|
|
TYP(nindirectsyms,4);
|
|
/* number of indirect symbol table entries */
|
|
|
|
/*
|
|
* To support relocating an individual module in a library
|
|
* file quickly the
|
|
* external relocation entries for each module in the
|
|
* library need to be
|
|
* accessed efficiently. Since the relocation entries
|
|
* can't be accessed
|
|
* through the section headers for a library file
|
|
* they are separated into
|
|
* groups of local and external entries further
|
|
* grouped by module. In this
|
|
* case the presents of this load command who's extreloff, nextrel,
|
|
* locreloff and nlocrel fields are non-zero indicates
|
|
* that the relocation
|
|
* entries of non-merged sections are not referenced
|
|
* through the section
|
|
* structures (and the reloff and nreloc fields
|
|
* in the section headers are
|
|
* set to zero).
|
|
*
|
|
* Since the relocation entries are not accessed
|
|
* through the section headers
|
|
* this requires the r_address field to be something other
|
|
* than a section
|
|
* offset to identify the item to be relocated.
|
|
* In this case r_address is
|
|
* set to the offset from the vmaddr of the first
|
|
* LC_SEGMENT command.
|
|
* For MH_SPLIT_SEGS images r_address is set to
|
|
* the the offset from the
|
|
* vmaddr of the first read-write LC_SEGMENT command.
|
|
*
|
|
* The relocation entries are grouped by module and the
|
|
* module table
|
|
* entries have indexes and counts into them for the
|
|
* group of external
|
|
* relocation entries for that the module.
|
|
*
|
|
* For sections that are merged across modules there must
|
|
* not be any
|
|
* remaining external relocation entries for them
|
|
* (for merged sections
|
|
* remaining relocation entries must be local).
|
|
*/
|
|
TYP(extreloff,4); /* offset to external relocation entries */
|
|
TYP(nextrel,4); /* number of external relocation entries */
|
|
|
|
/*
|
|
* All the local relocation entries are
|
|
* grouped together (they are not
|
|
* grouped by their module since they are only
|
|
* used if the object is moved
|
|
* from it staticly link edited address).
|
|
*/
|
|
TYP(locreloff,4); /* offset to local relocation entries */
|
|
TYP(nlocrel,4); /* number of local relocation entries */
|
|
};
|
|
|
|
/*
|
|
* An indirect symbol table entry is simply a 32bit index into
|
|
* the symbol table to the symbol that the pointer or stub is
|
|
* referring to. Unless it is for a * non-lazy symbol pointer
|
|
* section for a defined symbol which strip(1) has
|
|
* removed. In which case it has the value INDIRECT_SYMBOL_LOCAL.
|
|
* If the * symbol was also absolute INDIRECT_SYMBOL_ABS is or'ed
|
|
* with that.
|
|
*/
|
|
#define INDIRECT_SYMBOL_LOCAL 0x80000000
|
|
#define INDIRECT_SYMBOL_ABS 0x40000000
|
|
|
|
/* a table of contents entry */
|
|
struct dylib_table_of_contents {
|
|
TYP(symbol_index,4); /* the defined external symbol
|
|
(index into the symbol table) */
|
|
TYP(module_index,4); /* index into the module table this symbol
|
|
is defined in */
|
|
};
|
|
|
|
/* a module table entry */
|
|
struct dylib_module {
|
|
/* the module name (index into string table) */
|
|
TYP(module_name,4);
|
|
|
|
TYP(iextdefsym,4); /* index into externally defined symbols */
|
|
TYP(nextdefsym,4); /* number of externally defined symbols */
|
|
TYP(irefsym,4); /* index into reference symbol table */
|
|
TYP(nrefsym,4); /* number of reference symbol table entries */
|
|
TYP(ilocalsym,4); /* index into symbols for local symbols */
|
|
TYP(nlocalsym,4); /* number of local symbols */
|
|
|
|
TYP(iextrel,4); /* index into external relocation entries */
|
|
TYP(nextrel,4); /* number of external relocation entries */
|
|
|
|
TYP(iinit_iterm,4); /* low 16 bits are the index into the init
|
|
section, high 16 bits are the index into
|
|
the term section */
|
|
TYP(ninit_nterm,4); /* low 16 bits are the number of init section
|
|
entries, high 16 bits are the number of
|
|
term section entries */
|
|
|
|
/* for this module address of the start of */
|
|
/* the (__OBJC,__module_info) section */
|
|
TYP(objc_module_info_addr,4);
|
|
|
|
/* for this module size of */
|
|
/* the (__OBJC,__module_info) section */
|
|
TYP(objc_module_info_size,4);
|
|
};
|
|
|
|
/* a 64-bit module table entry */
|
|
struct dylib_module_64 {
|
|
/* the module name (index into string table) */
|
|
TYP(module_name,4);
|
|
|
|
TYP(iextdefsym,4); /* index into externally defined symbols */
|
|
TYP(nextdefsym,4); /* number of externally defined symbols */
|
|
TYP(irefsym,4); /* index into reference symbol table */
|
|
TYP(nrefsym,4); /* number of reference symbol table entries */
|
|
TYP(ilocalsym,4); /* index into symbols for local symbols */
|
|
TYP(nlocalsym,4); /* number of local symbols */
|
|
|
|
TYP(iextrel,4); /* index into external relocation entries */
|
|
TYP(nextrel,4); /* number of external relocation entries */
|
|
|
|
TYP(iinit_iterm,4); /* low 16 bits are the index into the init
|
|
section, high 16 bits are the index into
|
|
the term section */
|
|
TYP(ninit_nterm,4); /* low 16 bits are the number of init section
|
|
entries, high 16 bits are the number of
|
|
term section entries */
|
|
|
|
TYP(objc_module_info_size,4); /* for this module size of */
|
|
/* the (__OBJC,__module_info) section */
|
|
TYP(objc_module_info_addr,8);
|
|
/* for this module address of the start of */
|
|
/* the (__OBJC,__module_info) section */
|
|
};
|
|
|
|
/*
|
|
* The entries in the reference symbol
|
|
* table are used when loading the module
|
|
* (both by the static and dynamic link
|
|
* editors) and if the module is unloaded
|
|
* or replaced. Therefore all external
|
|
* symbols (defined and undefined) are
|
|
* listed in the module's reference table.
|
|
* The flags describe the type of
|
|
* reference that is being made.
|
|
* The constants for the flags are defined in
|
|
* <mach-o/nlist.h> as they are also used for symbol table entries.
|
|
*/
|
|
#if 0 /* dwarf readers not using this */
|
|
struct dylib_reference {
|
|
UNUSED uint32_t isym:24, /* index into the symbol table */
|
|
UNUSED flags:8; /* flags to indicate the type of reference */
|
|
};
|
|
#endif /* 0 */
|
|
|
|
/*
|
|
* The twolevel_hints_command contains the
|
|
* offset and number of hints in the
|
|
* two-level namespace lookup hints table.
|
|
*/
|
|
struct twolevel_hints_command {
|
|
TYP(cmd,4); /* LC_TWOLEVEL_HINTS */
|
|
TYP(cmdsize,4); /* sizeof(struct twolevel_hints_command) */
|
|
TYP(offset,4); /* offset to the hint table */
|
|
TYP(nhints,4); /* number of hints in the hint table */
|
|
};
|
|
|
|
/*
|
|
* The entries in the two-level namespace lookup
|
|
* hints table are twolevel_hint
|
|
* structs. These provide hints to the
|
|
* dynamic link editor where to start
|
|
* looking for an undefined symbol in a two-level namespace image. The
|
|
* isub_image field is an index into the sub-images (sub-frameworks and
|
|
* sub-umbrellas list) that made up the
|
|
* two-level image that the undefined
|
|
* symbol was found in when it was built by the static link editor. If
|
|
* isub-image is 0 the the symbol is expected
|
|
* to be defined in library and not
|
|
* in the sub-images.
|
|
* If isub-image is non-zero it is an index into the array
|
|
* of sub-images for the umbrella with the first
|
|
* index in the sub-images being
|
|
* 1. The array of sub-images is the ordered
|
|
* list of sub-images of the umbrella
|
|
* that would be searched for a symbol that
|
|
* has the umbrella recorded as its
|
|
* primary library.
|
|
* The table of contents index is an index into the
|
|
* library's table of contents.
|
|
* This is used as the starting point of the
|
|
* binary search or a directed linear search.
|
|
*/
|
|
#if 0
|
|
/* Not used by dwarf readers. */
|
|
struct twolevel_hint {
|
|
UNUSED uint32_t
|
|
isub_image:8, /* index into the sub images */
|
|
itoc:24; /* index into the table of contents */
|
|
};
|
|
#endif
|
|
|
|
/*
|
|
* The prebind_cksum_command contains the value of
|
|
* the original check sum for
|
|
* prebound files or zero.
|
|
* When a prebound file is first created or modified
|
|
* for other than updating its prebinding information
|
|
* the value of the check sum
|
|
* is set to zero.
|
|
* When the file has it prebinding re-done and if the value of
|
|
* the check sum is zero the original check sum is
|
|
* calculated and stored in
|
|
* cksum field of this load command in the output file.
|
|
* If when the prebinding
|
|
* is re-done and the cksum field is non-zero it
|
|
* is left unchanged from the
|
|
* input file.
|
|
*/
|
|
struct prebind_cksum_command {
|
|
TYP(cmd,4); /* LC_PREBIND_CKSUM */
|
|
TYP(cmdsize,4); /* sizeof(struct prebind_cksum_command) */
|
|
TYP(cksum,4); /* the check sum or zero */
|
|
};
|
|
|
|
/*
|
|
* The uuid load command contains a single 128-bit
|
|
* unique random number that
|
|
* identifies an object produced by the static link editor.
|
|
*/
|
|
struct uuid_command {
|
|
TYP(cmd,4); /* LC_UUID */
|
|
TYP(cmdsize,4); /* sizeof(struct uuid_command) */
|
|
unsigned char uuid[16]; /* the 128-bit uuid */
|
|
};
|
|
|
|
/*
|
|
* The rpath_command contains a path which
|
|
* at runtime should be added to
|
|
* the current run path used to find @rpath prefixed dylibs.
|
|
*/
|
|
struct rpath_command {
|
|
TYP(cmd,4); /* LC_RPATH */
|
|
TYP(cmdsize,4); /* includes string */
|
|
union lc_str path; /* path to add to run path */
|
|
};
|
|
|
|
/*
|
|
* The linkedit_data_command contains the offsets and sizes of a blob
|
|
* of data in the __LINKEDIT segment.
|
|
*/
|
|
struct linkedit_data_command {
|
|
TYP(cmd,4); /* LC_CODE_SIGNATURE, LC_SEGMENT_SPLIT_INFO,
|
|
LC_FUNCTION_STARTS, LC_DATA_IN_CODE,
|
|
LC_DYLIB_CODE_SIGN_DRS or
|
|
LC_LINKER_OPTIMIZATION_HINT. */
|
|
TYP(cmdsize,4); /* sizeof(struct linkedit_data_command) */
|
|
TYP(dataoff,4); /* file offset of data in __LINKEDIT segment */
|
|
TYP(datasize,4); /* file size of data in __LINKEDIT segment */
|
|
};
|
|
|
|
/*
|
|
* The encryption_info_command contains the file offset and size of an
|
|
* of an encrypted segment.
|
|
*/
|
|
struct encryption_info_command {
|
|
TYP(cmd,4); /* LC_ENCRYPTION_INFO */
|
|
TYP(cmdsize,4); /* sizeof(struct encryption_info_command) */
|
|
TYP(cryptoff,4); /* file offset of encrypted range */
|
|
TYP(cryptsize,4); /* file size of encrypted range */
|
|
TYP(cryptid,4); /* which encryption system,
|
|
0 means not-encrypted yet */
|
|
};
|
|
|
|
/*
|
|
* The encryption_info_command_64 contains
|
|
* the file offset and size of an
|
|
* of an encrypted segment (for use in x86_64 targets).
|
|
*/
|
|
struct encryption_info_command_64 {
|
|
TYP(cmd,4); /* LC_ENCRYPTION_INFO_64 */
|
|
TYP(cmdsize,4); /* sizeof(struct encryption_info_command_64) */
|
|
TYP(cryptoff,4); /* file offset of encrypted range */
|
|
TYP(cryptsize,4); /* file size of encrypted range */
|
|
TYP(cryptid,4); /* which encryption system,
|
|
0 means not-encrypted yet */
|
|
TYP(pad,4); /* padding to make this struct's size a multiple
|
|
of 8 bytes */
|
|
};
|
|
|
|
/*
|
|
* The version_min_command contains the min OS version on which this
|
|
* binary was built to run.
|
|
*/
|
|
struct version_min_command {
|
|
TYP(cmd,4); /* LC_VERSION_MIN_MACOSX or
|
|
LC_VERSION_MIN_IPHONEOS or
|
|
LC_VERSION_MIN_WATCHOS or
|
|
LC_VERSION_MIN_TVOS */
|
|
TYP(cmdsize,4); /* sizeof(struct min_version_command) */
|
|
TYP(version,4); /* X.Y.Z is encoded in nibbles xxxx.yy.zz */
|
|
TYP(sdk,4); /* X.Y.Z is encoded in nibbles xxxx.yy.zz */
|
|
};
|
|
|
|
/*
|
|
* The dyld_info_command contains the file offsets and sizes of
|
|
* the new compressed form of the information dyld needs to
|
|
* load the image. This information is used by dyld on Mac OS X
|
|
* 10.6 and later. All information pointed to by this command
|
|
* is encoded using byte streams, so no endian swapping is needed
|
|
* to interpret it.
|
|
*/
|
|
struct dyld_info_command {
|
|
TYP(cmd,4); /* LC_DYLD_INFO or LC_DYLD_INFO_ONLY */
|
|
TYP(cmdsize,4); /* sizeof(struct dyld_info_command) */
|
|
|
|
/*
|
|
* Dyld rebases an image whenever dyld loads it at
|
|
* an address different
|
|
* from its preferred address. The rebase information is a stream
|
|
* of byte sized opcodes whose symbolic names start
|
|
* with REBASE_OPCODE_.
|
|
* Conceptually the rebase information is a table of tuples:
|
|
* <seg-index, seg-offset, type>
|
|
* The opcodes are a compressed way to encode the table by only
|
|
* encoding when a column changes. In addition simple patterns
|
|
* like "every n'th offset for m times" can be encoded in a few
|
|
* bytes.
|
|
*/
|
|
TYP(rebase_off,4); /* file offset to rebase info */
|
|
TYP(rebase_size,4); /* size of rebase info */
|
|
|
|
/*
|
|
* Dyld binds an image during the loading process, if the image
|
|
* requires any pointers to be initialized to symbols
|
|
* in other images.
|
|
* The bind information is a stream of byte sized
|
|
* opcodes whose symbolic names start with BIND_OPCODE_.
|
|
* Conceptually the bind information is a table of tuples:
|
|
* <seg-index, seg-offset, type, symbol-library-ordinal,
|
|
* symbol-name, addend>
|
|
* The opcodes are a compressed way to encode the table by only
|
|
* encoding when a column changes. In addition simple patterns
|
|
* like for runs of pointers initialzed to the same value can be
|
|
* encoded in a few bytes.
|
|
*/
|
|
TYP(bind_off,4); /* file offset to binding info */
|
|
TYP(bind_size,4); /* size of binding info */
|
|
|
|
/*
|
|
* Some C++ programs require dyld to unique symbols so that all
|
|
* images in the process use the same copy of some code/data.
|
|
* This step is done after binding. The content of the weak_bind
|
|
* info is an opcode stream like the bind_info. But it is sorted
|
|
* alphabetically by symbol name. This enable dyld to walk
|
|
* all images with weak binding information in order and look
|
|
* for collisions. If there are no collisions, dyld does
|
|
* no updating. That means that some fixups are also encoded
|
|
* in the bind_info. For instance, all calls to "operator new"
|
|
* are first bound to libstdc++.dylib using the information
|
|
* in bind_info. Then if some image overrides operator new
|
|
* that is detected when the weak_bind information is processed
|
|
* and the call to operator new is then rebound.
|
|
*/
|
|
TYP(weak_bind_off,4); /* file offset to weak binding info */
|
|
TYP(weak_bind_size,4); /* size of weak binding info */
|
|
|
|
/*
|
|
* Some uses of external symbols do not need to be
|
|
* bound immediately.
|
|
* Instead they can be lazily bound on first use. The lazy_bind
|
|
* are contains a stream of BIND opcodes to bind all lazy symbols.
|
|
* Normal use is that dyld ignores the lazy_bind section when
|
|
* loading an image. Instead the static linker arranged for the
|
|
* lazy pointer to initially point to a helper function which
|
|
* pushes the offset into the lazy_bind area for the symbol
|
|
* needing to be bound, then jumps to dyld which simply adds
|
|
* the offset to lazy_bind_off to get the information on what
|
|
* to bind.
|
|
*/
|
|
TYP(lazy_bind_off,4); /* file offset to lazy binding info */
|
|
TYP(lazy_bind_size,4); /* size of lazy binding infs */
|
|
|
|
/*
|
|
* The symbols exported by a dylib are encoded in a trie. This
|
|
* is a compact representation that factors out common prefixes.
|
|
* It also reduces LINKEDIT pages in RAM because it encodes all
|
|
* information (name, address, flags) in one
|
|
* small, contiguous range.
|
|
* The export area is a stream of nodes.
|
|
* The first node sequentially
|
|
* is the start node for the trie.
|
|
*
|
|
* Nodes for a symbol start with a uleb128 that is the length of
|
|
* the exported symbol information for the string so far.
|
|
* If there is no exported symbol, the node starts with
|
|
* a zero byte.
|
|
* If there is exported info, it follows the length.
|
|
*
|
|
* First is a uleb128 containing flags. Normally, it is followed by
|
|
* a uleb128 encoded offset which is location of the content named
|
|
* by the symbol from the mach_header for the image. If the flags
|
|
* is EXPORT_SYMBOL_FLAGS_REEXPORT, then following the flags is
|
|
* a uleb128 encoded library ordinal, then a zero terminated
|
|
* UTF8 string. If the string is zero length, then the symbol
|
|
* is re-export from the specified dylib with the same name.
|
|
* If the flags is EXPORT_SYMBOL_FLAGS_STUB_AND_RESOLVER,
|
|
* then following
|
|
* the flags is two uleb128s: the stub offset and
|
|
* the resolver offset.
|
|
* The stub is used by non-lazy pointers. The resolver is used
|
|
* by lazy pointers and must be called to get
|
|
* the actual address to use.
|
|
*
|
|
* After the optional exported symbol information is a byte of
|
|
* how many edges (0-255) that this node has leaving it,
|
|
* followed by each edge.
|
|
* Each edge is a zero terminated UTF8 of the addition chars
|
|
* in the symbol, followed by a uleb128 offset for the node that
|
|
* edge points to.
|
|
*
|
|
*/
|
|
TYP(export_off,4); /* file offset to lazy binding info */
|
|
TYP(export_size,4); /* size of lazy binding infs */
|
|
};
|
|
|
|
/*
|
|
* The following are used to encode rebasing information
|
|
*/
|
|
#define REBASE_TYPE_POINTER 1
|
|
#define REBASE_TYPE_TEXT_ABSOLUTE32 2
|
|
#define REBASE_TYPE_TEXT_PCREL32 3
|
|
|
|
#define REBASE_OPCODE_MASK 0xF0
|
|
#define REBASE_IMMEDIATE_MASK 0x0F
|
|
#define REBASE_OPCODE_DONE 0x00
|
|
#define REBASE_OPCODE_SET_TYPE_IMM 0x10
|
|
#define REBASE_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB 0x20
|
|
#define REBASE_OPCODE_ADD_ADDR_ULEB 0x30
|
|
#define REBASE_OPCODE_ADD_ADDR_IMM_SCALED 0x40
|
|
#define REBASE_OPCODE_DO_REBASE_IMM_TIMES 0x50
|
|
#define REBASE_OPCODE_DO_REBASE_ULEB_TIMES 0x60
|
|
#define REBASE_OPCODE_DO_REBASE_ADD_ADDR_ULEB 0x70
|
|
#define REBASE_OPCODE_DO_REBASE_ULEB_TIMES_SKIPPING_ULEB 0x80
|
|
|
|
/*
|
|
* The following are used to encode binding information
|
|
*/
|
|
#define BIND_TYPE_POINTER 1
|
|
#define BIND_TYPE_TEXT_ABSOLUTE32 2
|
|
#define BIND_TYPE_TEXT_PCREL32 3
|
|
|
|
#define BIND_SPECIAL_DYLIB_SELF 0
|
|
#define BIND_SPECIAL_DYLIB_MAIN_EXECUTABLE -1
|
|
#define BIND_SPECIAL_DYLIB_FLAT_LOOKUP -2
|
|
|
|
#define BIND_SYMBOL_FLAGS_WEAK_IMPORT 0x1
|
|
#define BIND_SYMBOL_FLAGS_NON_WEAK_DEFINITION 0x8
|
|
|
|
#define BIND_OPCODE_MASK 0xF0
|
|
#define BIND_IMMEDIATE_MASK 0x0F
|
|
#define BIND_OPCODE_DONE 0x00
|
|
#define BIND_OPCODE_SET_DYLIB_ORDINAL_IMM 0x10
|
|
#define BIND_OPCODE_SET_DYLIB_ORDINAL_ULEB 0x20
|
|
#define BIND_OPCODE_SET_DYLIB_SPECIAL_IMM 0x30
|
|
#define BIND_OPCODE_SET_SYMBOL_TRAILING_FLAGS_IMM 0x40
|
|
#define BIND_OPCODE_SET_TYPE_IMM 0x50
|
|
#define BIND_OPCODE_SET_ADDEND_SLEB 0x60
|
|
#define BIND_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB 0x70
|
|
#define BIND_OPCODE_ADD_ADDR_ULEB 0x80
|
|
#define BIND_OPCODE_DO_BIND 0x90
|
|
#define BIND_OPCODE_DO_BIND_ADD_ADDR_ULEB 0xA0
|
|
#define BIND_OPCODE_DO_BIND_ADD_ADDR_IMM_SCALED 0xB0
|
|
#define BIND_OPCODE_DO_BIND_ULEB_TIMES_SKIPPING_ULEB 0xC0
|
|
|
|
/*
|
|
* The following are used on the flags byte of a terminal node
|
|
* in the export information.
|
|
*/
|
|
#define EXPORT_SYMBOL_FLAGS_KIND_MASK 0x03
|
|
#define EXPORT_SYMBOL_FLAGS_KIND_REGULAR 0x00
|
|
#define EXPORT_SYMBOL_FLAGS_KIND_THREAD_LOCAL 0x01
|
|
#define EXPORT_SYMBOL_FLAGS_WEAK_DEFINITION 0x04
|
|
#define EXPORT_SYMBOL_FLAGS_REEXPORT 0x08
|
|
#define EXPORT_SYMBOL_FLAGS_STUB_AND_RESOLVER 0x10
|
|
|
|
/*
|
|
* The linker_option_command contains linker
|
|
* options embedded in object files.
|
|
*/
|
|
struct linker_option_command {
|
|
TYP(cmd,4); /* LC_LINKER_OPTION only used in MH_OBJECT filetypes*/
|
|
TYP(cmdsize,4);
|
|
TYP(count,4); /* number of strings */
|
|
/* concatenation of zero terminated UTF8 strings.
|
|
Zero filled at end to align */
|
|
};
|
|
|
|
/*
|
|
* The symseg_command contains the offset and size of the GNU style
|
|
* symbol table information as described in the header file <symseg.h>.
|
|
* The symbol roots of the symbol segments must
|
|
* also be aligned properly
|
|
* in the file. So the requirement of keeping the offsets aligned to a
|
|
* multiple of a 4 bytes translates to the length field of the symbol
|
|
* roots also being a multiple of a long.
|
|
* Also the padding must again be
|
|
* zeroed. (THIS IS OBSOLETE and no longer supported).
|
|
*/
|
|
struct symseg_command {
|
|
TYP(cmd,4); /* LC_SYMSEG */
|
|
TYP(cmdsize,4); /* sizeof(struct symseg_command) */
|
|
TYP(offset,4); /* symbol segment offset */
|
|
TYP(size,4); /* symbol segment size in bytes */
|
|
};
|
|
|
|
/*
|
|
* The ident_command contains a free format string table following the
|
|
* ident_command structure.
|
|
* The strings are null terminated and the size of
|
|
* the command is padded out with zero bytes to a multiple of 4 bytes/
|
|
* (THIS IS OBSOLETE and no longer supported).
|
|
*/
|
|
struct ident_command {
|
|
TYP(cmd,4); /* LC_IDENT */
|
|
TYP(cmdsize,4); /* strings that follow this command */
|
|
};
|
|
|
|
/*
|
|
* The fvmfile_command contains a reference to a
|
|
* file to be loaded at the
|
|
* specified virtual address. (Presently, this command is
|
|
* reserved for internal use. The kernel ignores
|
|
* this command when loading a program into
|
|
* memory).
|
|
*/
|
|
struct fvmfile_command {
|
|
TYP(cmd,4); /* LC_FVMFILE */
|
|
TYP(cmdsize,4); /* includes pathname string */
|
|
union lc_str name; /* files pathname */
|
|
TYP(header_addr,4); /* files virtual address */
|
|
};
|
|
|
|
/*
|
|
* The entry_point_command is a replacement for thread_command.
|
|
* It is used for main executables to specify the
|
|
* location (file offset)
|
|
* of main(). If -stack_size was used at link time, the stacksize
|
|
* field will contain the stack size need for the main thread.
|
|
*/
|
|
struct entry_point_command {
|
|
TYP(cmd,4); /* LC_MAIN only used in MH_EXECUTE filetypes */
|
|
TYP(cmdsize,4); /* 24 */
|
|
TYP(entryoff,8); /* file (__TEXT) offset of main() */
|
|
TYP(stacksize,8); /* if not zero, initial stack size */
|
|
};
|
|
|
|
/*
|
|
* The source_version_command is an optional load command containing
|
|
* the version of the sources used to build the binary.
|
|
*/
|
|
struct source_version_command {
|
|
TYP(cmd,4); /* LC_SOURCE_VERSION */
|
|
TYP(cmdsize,4); /* 16 */
|
|
TYP(version,8); /* A.B.C.D.E packed as a24.b10.c10.d10.e10 */
|
|
};
|
|
|
|
/*
|
|
* The LC_DATA_IN_CODE load commands uses a linkedit_data_command
|
|
* to point to an array of data_in_code_entry entries. Each entry
|
|
* describes a range of data in a code section.
|
|
*/
|
|
struct data_in_code_entry {
|
|
TYP(offset,4); /* from mach_header to start of data range*/
|
|
TYP(length,2); /* number of bytes in data range */
|
|
TYP(kind,2); /* a DICE_KIND_* value */
|
|
};
|
|
#define DICE_KIND_DATA 0x0001
|
|
#define DICE_KIND_JUMP_TABLE8 0x0002
|
|
#define DICE_KIND_JUMP_TABLE16 0x0003
|
|
#define DICE_KIND_JUMP_TABLE32 0x0004
|
|
#define DICE_KIND_ABS_JUMP_TABLE32 0x0005
|
|
|
|
/*
|
|
* Sections of type S_THREAD_LOCAL_VARIABLES contain an array
|
|
* of tlv_descriptor structures.
|
|
*/
|
|
struct tlv_descriptor
|
|
{
|
|
void* (*thunk)(struct tlv_descriptor*);
|
|
unsigned long key;
|
|
unsigned long offset;
|
|
};
|
|
#ifdef __cplusplus
|
|
}
|
|
#endif /* __cplusplus */
|
|
#endif /* MACHO_LOADER_H */
|