update_dyld_sim_shared_cache.cpp [plain text]
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/mman.h>
#include <mach/mach.h>
#include <mach/mach_time.h>
#include <limits.h>
#include <stdarg.h>
#include <stdio.h>
#include <stdlib.h>
#include <math.h>
#include <fcntl.h>
#include <dlfcn.h>
#include <signal.h>
#include <errno.h>
#include <assert.h>
#include <sys/uio.h>
#include <unistd.h>
#include <sys/param.h>
#include <sys/sysctl.h>
#include <sys/resource.h>
#include <dirent.h>
#include <rootless.h>
#include <dscsym.h>
#include <dispatch/dispatch.h>
#include <pthread/pthread.h>
#include <algorithm>
#include <vector>
#include <unordered_set>
#include <unordered_set>
#include <iostream>
#include <fstream>
#include "MachOParser.h"
#include "FileUtils.h"
#include "StringUtils.h"
#include "DyldSharedCache.h"
struct MappedMachOsByCategory
{
std::string archName;
std::vector<DyldSharedCache::MappedMachO> dylibsForCache;
std::vector<DyldSharedCache::MappedMachO> otherDylibsAndBundles;
std::vector<DyldSharedCache::MappedMachO> mainExecutables;
};
static const char* sSearchDirs[] = {
"/bin",
"/sbin",
"/usr",
"/System",
};
static const char* sSkipDirs[] = {
"/usr/share",
"/usr/local/include",
};
static const char* sMacOsAdditions[] = {
"/usr/lib/system/libsystem_kernel.dylib",
"/usr/lib/system/libsystem_platform.dylib",
"/usr/lib/system/libsystem_pthread.dylib",
};
static bool verbose = false;
static bool addIfMachO(const std::string& simRuntimeRootPath, const std::string& runtimePath, const struct stat& statBuf, dyld3::Platform platform, std::vector<MappedMachOsByCategory>& files)
{
std::string fullPath = simRuntimeRootPath + runtimePath;
int fd = ::open(fullPath.c_str(), O_RDONLY);
if ( fd < 0 )
return false;
bool result = false;
const void* wholeFile = ::mmap(NULL, statBuf.st_size, PROT_READ, MAP_PRIVATE, fd, 0);
if ( wholeFile != MAP_FAILED ) {
Diagnostics diag;
bool usedWholeFile = false;
for (MappedMachOsByCategory& file : files) {
size_t sliceOffset;
size_t sliceLength;
bool fatButMissingSlice;
const void* slice = MAP_FAILED;
if ( dyld3::FatUtil::isFatFileWithSlice(diag, wholeFile, statBuf.st_size, file.archName, sliceOffset, sliceLength, fatButMissingSlice) ) {
slice = ::mmap(NULL, sliceLength, PROT_READ, MAP_PRIVATE, fd, sliceOffset);
if ( slice != MAP_FAILED ) {
if ( !dyld3::MachOParser::isValidMachO(diag, file.archName, platform, slice, sliceLength, fullPath.c_str(), false) ) {
::munmap((void*)slice, sliceLength);
slice = MAP_FAILED;
}
}
}
else if ( !fatButMissingSlice && dyld3::MachOParser::isValidMachO(diag, file.archName, platform, wholeFile, statBuf.st_size, fullPath.c_str(), false) ) {
slice = wholeFile;
sliceLength = statBuf.st_size;
sliceOffset = 0;
usedWholeFile = true;
}
if ( slice != MAP_FAILED ) {
const mach_header* mh = (mach_header*)slice;
dyld3::MachOParser parser(mh);
if ( parser.platform() != platform ) {
fprintf(stderr, "skipped wrong platform binary: %s\n", fullPath.c_str());
result = false;
}
else {
bool sip = true; if ( parser.isDynamicExecutable() ) {
bool issetuid = (statBuf.st_mode & (S_ISUID|S_ISGID));
file.mainExecutables.emplace_back(runtimePath, mh, sliceLength, issetuid, sip, sliceOffset, statBuf.st_mtime, statBuf.st_ino);
}
else {
if ( parser.canBePlacedInDyldCache(runtimePath) ) {
file.dylibsForCache.emplace_back(runtimePath, mh, sliceLength, false, sip, sliceOffset, statBuf.st_mtime, statBuf.st_ino);
}
else {
file.otherDylibsAndBundles.emplace_back(runtimePath, mh, sliceLength, false, sip, sliceOffset, statBuf.st_mtime, statBuf.st_ino);
}
}
result = true;
}
}
}
if ( !usedWholeFile )
::munmap((void*)wholeFile, statBuf.st_size);
}
::close(fd);
return result;
}
static void findAllFiles(const std::string& simRuntimeRootPath, dyld3::Platform platform, std::vector<MappedMachOsByCategory>& files)
{
std::unordered_set<std::string> skipDirs;
for (const char* s : sSkipDirs)
skipDirs.insert(s);
for (const char* searchDir : sSearchDirs ) {
iterateDirectoryTree(simRuntimeRootPath, searchDir, ^(const std::string& dirPath) { return (skipDirs.count(dirPath) != 0); }, ^(const std::string& path, const struct stat& statBuf) {
const bool hasXBit = ((statBuf.st_mode & S_IXOTH) == S_IXOTH);
if ( !hasXBit && !endsWith(path, ".dylib") )
return;
if ( statBuf.st_size < 0x3000 )
return;
addIfMachO(simRuntimeRootPath, path, statBuf, platform, files);
});
}
}
static void addMacOSAdditions(std::vector<MappedMachOsByCategory>& allFileSets)
{
for (const char* addPath : sMacOsAdditions) {
struct stat statBuf;
if ( stat(addPath, &statBuf) == 0 )
addIfMachO("", addPath, statBuf, dyld3::Platform::macOS, allFileSets);
}
}
static bool dontCache(const std::string& simRuntimeRootPath, const std::string& archName,
const std::unordered_set<std::string>& pathsWithDuplicateInstallName,
const DyldSharedCache::MappedMachO& aFile, bool warn)
{
if ( startsWith(aFile.runtimePath, "/usr/lib/system/introspection/") )
return true;
if ( startsWith(aFile.runtimePath, "/usr/local/") )
return true;
if ( aFile.runtimePath.find(".app/") != std::string::npos )
return true;
if ( aFile.runtimePath.find("//") != std::string::npos ) {
if (warn) fprintf(stderr, "update_dyld_sim_shared_cache: warning: %s double-slash in install name %s\n", archName.c_str(), aFile.runtimePath.c_str());
}
dyld3::MachOParser parser(aFile.mh);
const char* installName = parser.installName();
if ( (pathsWithDuplicateInstallName.count(aFile.runtimePath) != 0) && (aFile.runtimePath != installName) ) {
if (warn) fprintf(stderr, "update_dyld_sim_shared_cache: warning: %s skipping because of duplicate install name %s\n", archName.c_str(), aFile.runtimePath.c_str());
return true;
}
if ( aFile.runtimePath != installName ) {
std::string fullInstall = simRuntimeRootPath + installName;
char resolvedPath[PATH_MAX];
if ( realpath(fullInstall.c_str(), resolvedPath) != NULL ) {
std::string resolvedSymlink = resolvedPath;
if ( !simRuntimeRootPath.empty() ) {
resolvedSymlink = resolvedSymlink.substr(simRuntimeRootPath.size());
}
if ( aFile.runtimePath == resolvedSymlink ) {
return false;
}
}
if (warn) fprintf(stderr, "update_dyld_sim_shared_cache: warning: %s skipping because of bad install name %s\n", archName.c_str(), aFile.runtimePath.c_str());
return true;
}
return false;
}
static void pruneCachedDylibs(const std::string& simRuntimeRootPath, MappedMachOsByCategory& fileSet)
{
std::unordered_set<std::string> pathsWithDuplicateInstallName;
std::unordered_map<std::string, std::string> installNameToFirstPath;
for (DyldSharedCache::MappedMachO& aFile : fileSet.dylibsForCache) {
dyld3::MachOParser parser(aFile.mh);
const char* installName = parser.installName();
auto pos = installNameToFirstPath.find(installName);
if ( pos == installNameToFirstPath.end() ) {
installNameToFirstPath[installName] = aFile.runtimePath;
}
else {
pathsWithDuplicateInstallName.insert(aFile.runtimePath);
pathsWithDuplicateInstallName.insert(installNameToFirstPath[installName]);
}
}
for (DyldSharedCache::MappedMachO& aFile : fileSet.dylibsForCache) {
if ( dontCache(simRuntimeRootPath, fileSet.archName, pathsWithDuplicateInstallName, aFile, true) )
fileSet.otherDylibsAndBundles.push_back(aFile);
}
fileSet.dylibsForCache.erase(std::remove_if(fileSet.dylibsForCache.begin(), fileSet.dylibsForCache.end(),
[&](const DyldSharedCache::MappedMachO& aFile) { return dontCache(simRuntimeRootPath, fileSet.archName, pathsWithDuplicateInstallName, aFile, false); }),
fileSet.dylibsForCache.end());
}
static bool existingCacheUpToDate(const std::string& existingCache, const std::vector<DyldSharedCache::MappedMachO>& currentDylibs)
{
int fd = ::open(existingCache.c_str(), O_RDONLY);
if ( fd < 0 )
return false;
std::unordered_map<std::string, const DyldSharedCache::MappedMachO*> currentDylibMap;
for (const DyldSharedCache::MappedMachO& aFile : currentDylibs) {
currentDylibMap[aFile.runtimePath] = &aFile;
}
__block bool foundMismatch = false;
const uint64_t cacheMapLen = 0x40000000;
void *p = ::mmap(NULL, cacheMapLen, PROT_READ, MAP_PRIVATE, fd, 0);
if ( p != MAP_FAILED ) {
const DyldSharedCache* cache = (DyldSharedCache*)p;
cache->forEachImageEntry(^(const char* installName, uint64_t mTime, uint64_t inode) {
bool foundMatch = false;
auto pos = currentDylibMap.find(installName);
if ( pos != currentDylibMap.end() ) {
const DyldSharedCache::MappedMachO* foundDylib = pos->second;
if ( (foundDylib->inode == inode) && (foundDylib->modTime == mTime) ) {
foundMatch = true;
}
}
if ( !foundMatch ) {
bool foundSlow = false;
for (const DyldSharedCache::MappedMachO& aFile : currentDylibs) {
if ( (aFile.inode == inode) && (aFile.modTime == mTime) ) {
foundSlow = true;
break;
}
}
if ( !foundSlow ) {
foundMismatch = true;
if ( verbose )
fprintf(stderr, "rebuilding dyld cache because dylib changed: %s\n", installName);
}
}
});
::munmap(p, cacheMapLen);
}
::close(fd);
return !foundMismatch;
}
inline uint32_t absolutetime_to_milliseconds(uint64_t abstime)
{
return (uint32_t)(abstime/1000/1000);
}
#define TERMINATE_IF_LAST_ARG( s ) \
do { \
if ( i == argc - 1 ) { \
fprintf(stderr, s ); \
return 1; \
} \
} while ( 0 )
int main(int argc, const char* argv[])
{
std::string rootPath;
std::string dylibListFile;
bool force = false;
std::string cacheDir;
std::unordered_set<std::string> archStrs;
dyld3::Platform platform = dyld3::Platform::iOS;
for (int i = 1; i < argc; ++i) {
const char* arg = argv[i];
if (strcmp(arg, "-debug") == 0) {
verbose = true;
}
else if (strcmp(arg, "-verbose") == 0) {
verbose = true;
}
else if (strcmp(arg, "-tvOS") == 0) {
platform = dyld3::Platform::tvOS;
}
else if (strcmp(arg, "-iOS") == 0) {
platform = dyld3::Platform::iOS;
}
else if (strcmp(arg, "-watchOS") == 0) {
platform = dyld3::Platform::watchOS;
}
else if ( strcmp(arg, "-runtime_dir") == 0 ) {
TERMINATE_IF_LAST_ARG("-runtime_dir missing path argument\n");
rootPath = argv[++i];
}
else if (strcmp(arg, "-cache_dir") == 0) {
TERMINATE_IF_LAST_ARG("-cache_dir missing path argument\n");
cacheDir = argv[++i];
}
else if (strcmp(arg, "-arch") == 0) {
TERMINATE_IF_LAST_ARG("-arch missing argument\n");
archStrs.insert(argv[++i]);
}
else if (strcmp(arg, "-force") == 0) {
force = true;
}
else {
fprintf(stderr, "update_dyld_sim_shared_cache: unknown option: %s\n", arg);
return 1;
}
}
if ( cacheDir.empty() ) {
fprintf(stderr, "missing -cache_dir <path> option to specify directory in which to write cache file(s)\n");
return 1;
}
if ( rootPath.empty() ) {
fprintf(stderr, "missing -runtime_dir <path> option to specify directory which is root of simulator runtime)\n");
return 1;
}
else {
char resolvedPath[PATH_MAX];
if ( realpath(rootPath.c_str(), resolvedPath) != NULL ) {
rootPath = resolvedPath;
}
}
int err = mkpath_np(cacheDir.c_str(), S_IRWXU | S_IRGRP|S_IXGRP | S_IROTH|S_IXOTH);
if ( (err != 0) && (err != EEXIST) ) {
fprintf(stderr, "mkpath_np fail: %d", err);
return 1;
}
if ( archStrs.empty() ) {
switch ( platform ) {
case dyld3::Platform::iOS:
archStrs.insert("x86_64");
break;
case dyld3::Platform::tvOS:
archStrs.insert("x86_64");
break;
case dyld3::Platform::watchOS:
archStrs.insert("i386");
break;
case dyld3::Platform::unknown:
case dyld3::Platform::macOS:
assert(0 && "macOS does not have a simulator");
break;
case dyld3::Platform::bridgeOS:
assert(0 && "bridgeOS does not have a simulator");
break;
}
}
uint64_t t1 = mach_absolute_time();
__block std::vector<MappedMachOsByCategory> allFileSets;
if ( archStrs.count("x86_64") )
allFileSets.push_back({"x86_64"});
if ( archStrs.count("i386") )
allFileSets.push_back({"i386"});
findAllFiles(rootPath, platform, allFileSets);
addMacOSAdditions(allFileSets);
for (MappedMachOsByCategory& fileSet : allFileSets) {
pruneCachedDylibs(rootPath, fileSet);
}
uint64_t t2 = mach_absolute_time();
fprintf(stderr, "time to scan file system and construct lists of mach-o files: %ums\n", absolutetime_to_milliseconds(t2-t1));
__block bool cacheBuildFailure = false;
dispatch_apply(allFileSets.size(), dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^(size_t index) {
MappedMachOsByCategory& fileSet = allFileSets[index];
const std::string outFile = cacheDir + "/dyld_shared_cache_" + fileSet.archName;
__block std::unordered_set<std::string> knownMissingDylib;
DyldSharedCache::MappedMachO (^loader)(const std::string&) = ^DyldSharedCache::MappedMachO(const std::string& runtimePath) {
std::string fullPath = rootPath + runtimePath;
struct stat statBuf;
if ( stat(fullPath.c_str(), &statBuf) == 0 ) {
std::vector<MappedMachOsByCategory> mappedFiles;
mappedFiles.push_back({fileSet.archName});
if ( addIfMachO(rootPath, runtimePath, statBuf, platform, mappedFiles) ) {
if ( !mappedFiles.back().dylibsForCache.empty() )
return mappedFiles.back().dylibsForCache.back();
}
}
if ( knownMissingDylib.count(runtimePath) == 0 ) {
fprintf(stderr, "update_dyld_sim_shared_cache: warning: %s could not use in dylid cache: %s\n", fileSet.archName.c_str(), runtimePath.c_str());
knownMissingDylib.insert(runtimePath);
}
return DyldSharedCache::MappedMachO();
};
size_t startCount = fileSet.dylibsForCache.size();
std::vector<std::pair<DyldSharedCache::MappedMachO, std::set<std::string>>> excludes;
DyldSharedCache::verifySelfContained(fileSet.dylibsForCache, loader, excludes);
for (size_t i=startCount; i < fileSet.dylibsForCache.size(); ++i) {
fprintf(stderr, "update_dyld_sim_shared_cache: warning: %s not found in initial scan, but adding required dylib %s\n", fileSet.archName.c_str(), fileSet.dylibsForCache[i].runtimePath.c_str());
}
for (auto& exclude : excludes) {
std::string reasons = "(\"";
for (auto i = exclude.second.begin(); i != exclude.second.end(); ++i) {
reasons += *i;
if (i != --exclude.second.end()) {
reasons += "\", \"";
}
}
reasons += "\")";
fprintf(stderr, "update_dyld_shared_cache: warning: %s rejected from cached dylibs: %s (%s)\n", fileSet.archName.c_str(), exclude.first.runtimePath.c_str(), reasons.c_str());
fileSet.otherDylibsAndBundles.push_back(exclude.first);
}
if ( !force ) {
if ( existingCacheUpToDate(outFile, fileSet.dylibsForCache) )
return;
}
fprintf(stderr, "make %s cache with %lu dylibs, %lu other dylibs, %lu programs\n", fileSet.archName.c_str(), fileSet.dylibsForCache.size(), fileSet.otherDylibsAndBundles.size(), fileSet.mainExecutables.size());
DyldSharedCache::CreateOptions options;
options.archName = fileSet.archName;
options.platform = platform;
options.excludeLocalSymbols = false;
options.optimizeStubs = false;
options.optimizeObjC = true;
options.codeSigningDigestMode = DyldSharedCache::SHA256only;
options.dylibsRemovedDuringMastering = false;
options.inodesAreSameAsRuntime = true;
options.cacheSupportsASLR = false;
options.forSimulator = true;
options.verbose = verbose;
options.evictLeafDylibsOnOverflow = true;
options.pathPrefixes = { rootPath };
DyldSharedCache::CreateResults results = DyldSharedCache::create(options, fileSet.dylibsForCache, fileSet.otherDylibsAndBundles, fileSet.mainExecutables);
for (const std::string& warn : results.warnings) {
fprintf(stderr, "update_dyld_sim_shared_cache: warning: %s %s\n", fileSet.archName.c_str(), warn.c_str());
}
if ( !results.errorMessage.empty() ) {
fprintf(stderr, "update_dyld_sim_shared_cache: %s\n", results.errorMessage.c_str());
cacheBuildFailure = true;
}
else {
assert(results.cacheContent != nullptr);
if ( !safeSave(results.cacheContent, results.cacheLength, outFile) )
cacheBuildFailure = true;
if ( !cacheBuildFailure ) {
std::string mapStr = results.cacheContent->mapFile();
std::string outFileMap = cacheDir + "/dyld_shared_cache_" + fileSet.archName + ".map";
safeSave(mapStr.c_str(), mapStr.size(), outFileMap);
}
vm_deallocate(mach_task_self(), (vm_address_t)results.cacheContent, results.cacheLength);
}
});
return (cacheBuildFailure ? 1 : 0);
}