dyld3/libdyldEntryVector.cpp

   1 /*
   2  * Copyright (c) 2017 Apple 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 #include <stdarg.h>
  25 #include <mach-o/dyld_priv.h>
  26 #include <mach-o/dyld_images.h>
  27
  28 #include "libdyldEntryVector.h"
  29 #include "AllImages.h"
  30 #include "Array.h"
  31 #include "Loading.h"
  32 #include "Logging.h"
  33 #include "PathOverrides.h"
  34 #include "StartGlue.h"
  35 #include "dyld_process_info_internal.h"
  36
  37 extern "C" char start;
  38
  39 VIS_HIDDEN const char** appleParams;
  40
  41 extern void* __ptrauth_dyld_address_auth gUseDyld3;
  42 extern bool gEnableSharedCacheDataConst;
  43
  44 namespace dyld3 {
  45
  46
  47 AllImages::ProgramVars sVars;
  48 static void (*sChildForkFunction)();
  49
  50 static const char* leafName(const char* argv0)
  51 {
  52     if ( argv0 == nullptr )
  53        return "";
  54
  55     if ( const char* lastSlash = strrchr(argv0, '/') )
  56         return lastSlash+1;
  57     else
  58         return argv0;
  59 }
  60
  61 static void entry_setVars(const mach_header* mainMH, int argc, const char* argv[], const char* envp[], const char* apple[],
  62                           bool keysOff, bool platformBinariesOnly, bool enableSharedCacheDataConst)
  63 {
  64     NXArgc       = argc;
  65     NXArgv       = argv;
  66     environ      = (char**)envp;
  67     appleParams  = apple;
  68     __progname   = leafName(argv[0]);
  69
  70     sVars.mh            = mainMH;
  71     sVars.NXArgcPtr     = &NXArgc;
  72     sVars.NXArgvPtr     = &NXArgv;
  73     sVars.environPtr    = (const char***)&environ;
  74     sVars.__prognamePtr = &__progname;
  75     gAllImages.setProgramVars(&sVars, keysOff, platformBinariesOnly);
  76
  77     gUseDyld3 = (void*)1;
  78
  79     setLoggingFromEnvs(envp);
  80
  81     gEnableSharedCacheDataConst = enableSharedCacheDataConst;
  82 }
  83
  84 static void entry_setHaltFunction(void (*func)(const char* message) __attribute__((noreturn)) )
  85 {
  86     setHaltFunction(func);
  87 }
  88
  89 static void entry_setLogFunction(void (*logFunction)(const char* format, va_list list))
  90 {
  91     setLoggingFunction(logFunction);
  92 }
  93
  94 static void entry_setOldAllImageInfo(dyld_all_image_infos* old)
  95 {
  96     gAllImages.setOldAllImageInfo(old);
  97 }
  98
  99 static void entry_setNotifyMonitoringDyldMain(void (*notifyMonitoringDyldMain)()) {
 100 #if !TARGET_OS_DRIVERKIT
 101     setNotifyMonitoringDyldMain(notifyMonitoringDyldMain);
 102 #endif
 103 }
 104
 105 static void entry_setNotifyMonitoringDyld(void (*notifyMonitoringDyld)(bool unloading,unsigned imageCount,
 106                                                                                const struct mach_header* loadAddresses[],
 107                                                                                const char* imagePaths[])) {
 108 #if !TARGET_OS_DRIVERKIT
 109     setNotifyMonitoringDyld(notifyMonitoringDyld);
 110 #endif
 111 }
 112
 113 static void entry_setInitialImageList(const closure::LaunchClosure* closure,
 114                                       const DyldSharedCache* dyldCacheLoadAddress, const char* dyldCachePath,
 115                                       const Array<LoadedImage>& initialImages, LoadedImage& libSystem,
 116                                       mach_port_t mach_task_self)
 117 {
 118     gAllImages.init(closure, dyldCacheLoadAddress, dyldCachePath, initialImages);
 119     gAllImages.applyInterposingToDyldCache(closure, mach_task_self);
 120
 121     // run initializer for libSytem.B.dylib
 122     // this calls back into _dyld_initializer which calls gAllIimages.addImages()
 123     gAllImages.runLibSystemInitializer(libSystem);
 124
 125     // now that malloc is available, parse DYLD_ env vars
 126     closure::gPathOverrides.setEnvVars((const char**)environ, gAllImages.mainExecutable(), gAllImages.mainExecutableImage()->path());
 127 }
 128
 129 static void entry_runInitialzersBottomUp(const mach_header* mainExecutableImageLoadAddress)
 130 {
 131     gAllImages.runStartupInitialzers();
 132 #if !TARGET_OS_DRIVERKIT
 133     gAllImages.notifyMonitorMain();
 134 #endif
 135 }
 136
 137 static void entry_setChildForkFunction(void (*func)() )
 138 {
 139     sChildForkFunction = func;
 140 }
 141
 142 static void entry_setRestrictions(bool allowAtPaths, bool allowEnvPaths, bool allowFallbackPaths)
 143 {
 144     gAllImages.setRestrictions(allowAtPaths, allowEnvPaths);
 145     closure::gPathOverrides.setFallbackPathHandling(allowFallbackPaths ?
 146                                                     dyld3::closure::PathOverrides::FallbackPathMode::classic :
 147                                                     dyld3::closure::PathOverrides::FallbackPathMode::restricted);
 148 }
 149
 150 static void entry_setHasCacheOverrides(bool someCacheImageOverriden)
 151 {
 152     gAllImages.setHasCacheOverrides(someCacheImageOverriden);
 153 }
 154
 155
 156 static void entry_setProgramVars(ProgramVars* progVars)
 157 {
 158     // this entry only called when running crt1.o based old macOS programs
 159     gAllImages.setProgramVars((AllImages::ProgramVars*)progVars, false, false);
 160 }
 161
 162 static void entry_setLaunchMode(uint32_t flags)
 163 {
 164     gAllImages.setLaunchMode(flags);
 165 }
 166
 167 static MainFunc entry_getDriverkitMain(void)
 168 {
 169     return gAllImages.getDriverkitMain();
 170 }
 171
 172
 173 static_assert((closure::kFormatVersion & LibDyldEntryVector::kBinaryFormatVersionMask) == closure::kFormatVersion, "binary format version overflow");
 174
 175 const LibDyldEntryVector entryVectorForDyld = {
 176     LibDyldEntryVector::kCurrentVectorVersion,
 177     closure::kFormatVersion,
 178     &entry_setVars,
 179     &entry_setHaltFunction,
 180     &entry_setOldAllImageInfo,
 181     &entry_setInitialImageList,
 182     &entry_runInitialzersBottomUp,
 183     (__typeof(LibDyldEntryVector::startFunc))address_of_start,
 184     &entry_setChildForkFunction,
 185     &entry_setLogFunction,
 186     &entry_setRestrictions,
 187     &entry_setNotifyMonitoringDyldMain,
 188     &entry_setNotifyMonitoringDyld,
 189     &entry_setHasCacheOverrides,
 190     &entry_setProgramVars,
 191     &entry_setLaunchMode,
 192     &entry_getDriverkitMain,
 193 };
 194
 195 VIS_HIDDEN void _dyld_atfork_prepare()
 196 {
 197     gAllImages.takeLockBeforeFork();
 198 }
 199
 200 VIS_HIDDEN void _dyld_atfork_parent()
 201 {
 202     gAllImages.releaseLockInForkParent();
 203 }
 204
 205 VIS_HIDDEN void _dyld_fork_child()
 206 {
 207     // Note the child fork function updates the data structures inside dyld
 208     (*sChildForkFunction)();
 209
 210     // And we then need to update the structures for dyld3 in libdyld
 211     gAllImages.resetLockInForkChild();
 212 }
 213
 214
 215 } // namespace dyld3
 216