lib/macho++.h

   1 /*
   2  * Copyright (c) 2006 Apple Computer, Inc. All Rights Reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * This file contains Original Code and/or Modifications of Original Code
   7  * as defined in and that are subject to the Apple Public Source License
   8  * Version 2.0 (the 'License'). You may not use this file except in
   9  * compliance with the License. Please obtain a copy of the License at
  10  * http://www.opensource.apple.com/apsl/ and read it before using this
  11  * file.
  12  *
  13  * The Original Code and all software distributed under the License are
  14  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  15  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  16  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  17  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  18  * Please see the License for the specific language governing rights and
  19  * limitations under the License.
  20  *
  21  * @APPLE_LICENSE_HEADER_END@
  22  */
  23
  24 //
  25 // macho++ - Mach-O object file helpers
  26 //
  27 #ifndef _H_MACHOPLUSPLUS
  28 #define _H_MACHOPLUSPLUS
  29
  30 #include <mach-o/loader.h>
  31 #include <mach-o/fat.h>
  32 #include <mach-o/arch.h>
  33 #include <security_utilities/globalizer.h>
  34 #include <security_utilities/endian.h>
  35 #include <security_utilities/unix++.h>
  36 #include <security_utilities/cfutilities.h>
  37
  38 namespace Security {
  39
  40
  41 //
  42 // An architecture specification.
  43 // Simply a pair or (cpu type, cpu subtype), really.
  44 //
  45 class Architecture : public std::pair<cpu_type_t, cpu_subtype_t> {
  46 public:
  47         Architecture() { }
  48         explicit Architecture(cpu_type_t type, cpu_subtype_t sub = 0)
  49                 : std::pair<cpu_type_t, cpu_subtype_t>(type, sub) { }
  50         Architecture(const fat_arch &archInFile);
  51
  52         cpu_type_t cpuType() const { return this->first; }
  53         cpu_subtype_t cpuSubtype() const { return this->second; }
  54         const char *name() const;
  55
  56 public:
  57         friend bool operator == (const Architecture &a1, const Architecture &a2)
  58         { return a1.cpuType() == a2.cpuType(); }
  59
  60         friend bool operator < (const Architecture &a1, const Architecture &a2)
  61         { return a1.cpuType() < a2.cpuType(); }
  62
  63 public:
  64         static Architecture local();
  65 };
  66
  67
  68 //
  69 // A Mach-O formatted file segment.
  70 //
  71 class MachO : public UnixPlusPlus::FileDesc {
  72 public:
  73         MachO(FileDesc fd, size_t offset = 0, size_t length = 0);
  74         ~MachO();
  75
  76         size_t offset() const { return mOffset; }
  77         size_t length() const { return mLength; }
  78
  79         template <class T>
  80         T flip(T value) const
  81         { return mFlip ? Security::flip(value) : value; }
  82
  83         bool isFlipped() const { return mFlip; }
  84         bool is64() const { return m64; }
  85
  86         Architecture architecture() const;
  87         uint32_t type() const;
  88         uint32_t flags() const;
  89
  90         const load_command *loadCommands() const { return mCommands; }
  91         const load_command *nextCommand(const load_command *command) const;
  92
  93         const segment_command *findSegment(const char *segname) const;
  94         const section *findSection(const char *segname, const char *sectname) const;
  95
  96         const linkedit_data_command *findCodeSignature() const;
  97
  98         size_t signingOffset() const;   // starting offset of CS section, or 0 if none
  99         size_t signingLength() const;   // length of CS section, or 0 if none
 100         size_t signingExtent() const;   // signingOffset, or file length if none
 101
 102         void seek(size_t offset);       // relative to start of image
 103         CFDataRef dataAt(size_t offset, size_t size);
 104
 105 private:
 106         size_t mOffset;                 // starting file offset
 107         size_t mLength;                 // Mach-O file length
 108         bool m64;                               // is 64-bit
 109         bool mFlip;                             // wrong byte order (flip all integers)
 110         mach_header mHeader;    // Mach-O header
 111         load_command *mCommands; // load commands
 112         load_command *mEndCommands; // end of load commands
 113 };
 114
 115
 116 //
 117 // A Universal object represents a Mach-O binary image (whole) file.
 118 // It can represent a true Universal (aka "Fat") file with multiple
 119 // architectures; but it will also represent a single Mach-O ("thin")
 120 // binary and make you believe it's a Universal with just one architecture.
 121 //
 122 class Universal : public UnixPlusPlus::FileDesc {
 123 public:
 124         Universal(FileDesc fd);
 125         ~Universal();
 126
 127         // return a genuine MachO object for the given architecture
 128         MachO *architecture() const;            // native
 129         MachO *architecture(const Architecture &arch) const; // given
 130
 131         // return (just) the starting offset of an architecture
 132         size_t archOffset() const;                      // native
 133         size_t archOffset(const Architecture &arch) const; // given
 134
 135         // return a set of architectures contained
 136         typedef std::set<Architecture> Architectures;
 137         void architectures(Architectures &archs);
 138
 139         bool isUniversal() const { return mArchList; }
 140         Architecture bestNativeArch() const;
 141
 142 public:
 143         static uint32_t typeOf(FileDesc fd);
 144
 145 private:
 146         const fat_arch *findArch(const Architecture &arch) const;
 147         MachO *findImage(const Architecture &arch) const;
 148
 149 private:
 150         fat_arch *mArchList;            // architectures (NULL if thin file)
 151         unsigned mArchCount;            // number of architectures (if fat)
 152         Architecture mThinArch;         // single architecture (if thin)
 153 };
 154
 155
 156 } // end namespace Security
 157
 158 #endif // !_H_MACHOPLUSPLUS