--- /dev/null
+/*
+ * Copyright (c) 2009 Apple Inc. All Rights Reserved.
+ *
+ * @APPLE_LICENSE_HEADER_START@
+ *
+ * This file contains Original Code and/or Modifications of Original Code
+ * as defined in and that are subject to the Apple Public Source License
+ * Version 2.0 (the 'License'). You may not use this file except in
+ * compliance with the License. Please obtain a copy of the License at
+ * http://www.opensource.apple.com/apsl/ and read it before using this
+ * file.
+ *
+ * The Original Code and all software distributed under the License are
+ * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
+ * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
+ * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
+ * Please see the License for the specific language governing rights and
+ * limitations under the License.
+ *
+ * @APPLE_LICENSE_HEADER_END@
+ */
+
+//
+// dyldcache - access layer to the DYLD Shared Library Cache file
+//
+#ifndef _H_DYLDCACHE
+#define _H_DYLDCACHE
+
+#include <security_utilities/unix++.h>
+#include <security_utilities/memutils.h>
+#include <security_utilities/macho++.h>
+#include <security_utilities/endian.h>
+#include "dyld_cache_format.h"
+
+
+//
+// One (architecture of the) Shared Library Cache.
+// We mmap the file rather than reading a copy, since its format is rather scattered, and we're not
+// interested in the vast majority of it.
+// This is a read-only view of the cache file. It will not allow modifications, though it may
+// tell you where in the file they should go.
+//
+class DYLDCache : public UnixPlusPlus::AutoFileDesc {
+public:
+ DYLDCache(const std::string &path);
+ virtual ~DYLDCache();
+
+ std::string magic() const { return mHeader->magic; }
+ uint64_t baseAddress() const { return flip(mHeader->dyldBaseAddress); }
+ Architecture architecture() const { return mArch->architecture(); }
+ size_t mapSize() const { return mSigStart; } // size of all the mappings
+ size_t signatureLength() const { return mSigLength; } // size of all the mappings
+ size_t totalSize() const { return mLength; } // size of entire file (>= mapSize(), we hope)
+
+ template <class Int> Int flip(Int x) const { return mFlip ? Security::flip(x) : x; }
+
+public:
+ static std::string pathFor(const Architecture &arch); // file path for given architecture
+ static bool validate(UnixPlusPlus::FileDesc &fd); // does this look like a shared library cache?
+
+protected:
+ template <class SubStruct>
+ class Item {
+ public:
+ Item(const DYLDCache &c, uint32_t off)
+ : cache(c), mStruct(c.at<SubStruct>(off)) { }
+ const DYLDCache &cache;
+
+ protected:
+ const SubStruct *mStruct;
+ template <class Int> Int flip(Int x) const { return cache.flip(x); }
+ };
+
+public:
+ //
+ // A contiguous mapping established by the cache builder
+ //
+ struct Mapping : public Item<shared_file_mapping_np> {
+ mach_vm_address_t address() const { return flip(mStruct->sfm_address); }
+ mach_vm_size_t size() const { return flip(mStruct->sfm_size); }
+ mach_vm_address_t limit() const { return address() + size(); }
+ mach_vm_offset_t offset() const { return flip(mStruct->sfm_file_offset); }
+ vm_prot_t maxProt() const { return flip(mStruct->sfm_max_prot); }
+ vm_prot_t initProt() const { return flip(mStruct->sfm_init_prot); }
+
+ bool contains(uint64_t address) const
+ { return address >= this->address() && address < this->limit(); }
+
+ Mapping(const DYLDCache &c, uint32_t off) : Item<shared_file_mapping_np>(c, off) { }
+ };
+
+ uint32_t mappingCount() const { return flip(mHeader->mappingCount); }
+ Mapping mapping(unsigned ix) const;
+
+ Mapping findMap(uint64_t address) const;
+ uint64_t mapAddress(uint64_t address) const;
+
+public:
+ //
+ // One original binary ("image") as embedded in the cache.
+ //
+ struct Image : public Item<dyld_cache_image_info> {
+ Image(const DYLDCache &c, uint32_t off) : Item<dyld_cache_image_info>(c, off) { }
+
+ uint64_t address() const { return flip(mStruct->address); }
+ uint64_t modTime() const { return flip(mStruct->modTime); }
+ uint64_t inode() const { return flip(mStruct->inode); }
+ uint32_t pad() const { return flip(mStruct->pad); }
+ std::string path() const { return cache.at<char>(flip(mStruct->pathFileOffset)); }
+ };
+
+ uint32_t imageCount() const { return flip(mHeader->imagesCount); }
+ Image image(unsigned ix) const;
+
+public:
+ template <class T>
+ const T *at(uint32_t offset) const
+ { return LowLevelMemoryUtilities::increment<const T>(mBase, offset); }
+
+private:
+ //
+ // A private table correlating cache "magic strings" to information we need about the cache
+ // (This should be in the cache files themselves)
+ //
+ struct ArchType {
+ cpu_type_t cpu; // main architecture
+ cpu_subtype_t sub; // subarchitecture
+ char magic[16]; // cache file magic string
+ char filename[10]; // conventional file name (off cacheFileBase)
+ uint16_t order; // byte order marker
+
+ std::string path() const
+ { return std::string(DYLD_SHARED_CACHE_DIR DYLD_SHARED_CACHE_BASE_NAME) + filename; }
+
+ Architecture architecture() const { return Architecture(cpu, sub); }
+ };
+ static const ArchType architectures[];
+
+ static const ArchType *matchArchitecture(const dyld_cache_header &header);
+
+private:
+ const void *mBase;
+ size_t mLength;
+
+ const dyld_cache_header *mHeader; // cache file header (NOT byte order corrected)
+ const ArchType *mArch; // ArchType entry that describes this file
+ bool mFlip; // need to flip all integers?
+ size_t mSigStart; // end of all file mappings (start of signature)
+ size_t mSigLength; // indicated length of signature
+};
+
+
+#endif //_H_DYLDCACHE
projects / apple / security.git / blobdiff