1 /* 2 * Copyright (C) 2008 The Android Open Source Project 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * * Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * * Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in 12 * the documentation and/or other materials provided with the 13 * distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 16 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 17 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 18 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE 19 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 21 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS 22 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 23 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 24 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT 25 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26 * SUCH DAMAGE. 27 */ 28 29 #ifndef _LINKER_H_ 30 #define _LINKER_H_ 31 32 #include <dlfcn.h> 33 #include <android/dlext.h> 34 #include <elf.h> 35 #include <inttypes.h> 36 #include <link.h> 37 #include <sys/stat.h> 38 #include <unistd.h> 39 40 #include "private/bionic_page.h" 41 #include "linked_list.h" 42 #include "linker_common_types.h" 43 #include "linker_logger.h" 44 #include "linker_soinfo.h" 45 46 #include <string> 47 #include <vector> 48 49 #if defined(__LP64__) 50 #define ELFW(what) ELF64_ ## what 51 #else 52 #define ELFW(what) ELF32_ ## what 53 #endif 54 55 // mips64 interprets Elf64_Rel structures' r_info field differently. 56 // bionic (like other C libraries) has macros that assume regular ELF files, 57 // but the dynamic linker needs to be able to load mips64 ELF files. 58 #if defined(__mips__) && defined(__LP64__) 59 #undef ELF64_R_SYM 60 #undef ELF64_R_TYPE 61 #undef ELF64_R_INFO 62 #define ELF64_R_SYM(info) (((info) >> 0) & 0xffffffff) 63 #define ELF64_R_SSYM(info) (((info) >> 32) & 0xff) 64 #define ELF64_R_TYPE3(info) (((info) >> 40) & 0xff) 65 #define ELF64_R_TYPE2(info) (((info) >> 48) & 0xff) 66 #define ELF64_R_TYPE(info) (((info) >> 56) & 0xff) 67 #endif 68 69 #define SUPPORTED_DT_FLAGS_1 (DF_1_NOW | DF_1_GLOBAL | DF_1_NODELETE | DF_1_PIE) 70 71 // Class used construct version dependency graph. 72 class VersionTracker { 73 public: 74 VersionTracker() = default; 75 bool init(const soinfo* si_from); 76 77 const version_info* get_version_info(ElfW(Versym) source_symver) const; 78 private: 79 bool init_verneed(const soinfo* si_from); 80 bool init_verdef(const soinfo* si_from); 81 void add_version_info(size_t source_index, ElfW(Word) elf_hash, 82 const char* ver_name, const soinfo* target_si); 83 84 std::vector<version_info> version_infos; 85 86 DISALLOW_COPY_AND_ASSIGN(VersionTracker); 87 }; 88 89 bool soinfo_do_lookup(soinfo* si_from, const char* name, const version_info* vi, 90 soinfo** si_found_in, const soinfo_list_t& global_group, 91 const soinfo_list_t& local_group, const ElfW(Sym)** symbol); 92 93 enum RelocationKind { 94 kRelocAbsolute = 0, 95 kRelocRelative, 96 kRelocCopy, 97 kRelocSymbol, 98 kRelocMax 99 }; 100 101 void count_relocation(RelocationKind kind); 102 103 soinfo* get_libdl_info(const char* linker_path, const link_map& linker_map); 104 105 soinfo* find_containing_library(const void* p); 106 107 void do_android_get_LD_LIBRARY_PATH(char*, size_t); 108 void do_android_update_LD_LIBRARY_PATH(const char* ld_library_path); 109 void* do_dlopen(const char* name, 110 int flags, 111 const android_dlextinfo* extinfo, 112 const void* caller_addr); 113 114 int do_dlclose(void* handle); 115 116 int do_dl_iterate_phdr(int (*cb)(dl_phdr_info* info, size_t size, void* data), void* data); 117 118 #if defined(__arm__) 119 _Unwind_Ptr do_dl_unwind_find_exidx(_Unwind_Ptr pc, int* pcount); 120 #endif 121 122 bool do_dlsym(void* handle, const char* sym_name, 123 const char* sym_ver, 124 const void* caller_addr, 125 void** symbol); 126 127 int do_dladdr(const void* addr, Dl_info* info); 128 129 // void ___cfi_slowpath(uint64_t CallSiteTypeId, void *Ptr, void *Ret); 130 // void ___cfi_slowpath_diag(uint64_t CallSiteTypeId, void *Ptr, void *DiagData, void *Ret); 131 void ___cfi_fail(uint64_t CallSiteTypeId, void* Ptr, void *DiagData, void *Ret); 132 133 void set_application_target_sdk_version(uint32_t target); 134 uint32_t get_application_target_sdk_version(); 135 136 enum { 137 /* A regular namespace is the namespace with a custom search path that does 138 * not impose any restrictions on the location of native libraries. 139 */ 140 ANDROID_NAMESPACE_TYPE_REGULAR = 0, 141 142 /* An isolated namespace requires all the libraries to be on the search path 143 * or under permitted_when_isolated_path. The search path is the union of 144 * ld_library_path and default_library_path. 145 */ 146 ANDROID_NAMESPACE_TYPE_ISOLATED = 1, 147 148 /* The shared namespace clones the list of libraries of the caller namespace upon creation 149 * which means that they are shared between namespaces - the caller namespace and the new one 150 * will use the same copy of a library if it was loaded prior to android_create_namespace call. 151 * 152 * Note that libraries loaded after the namespace is created will not be shared. 153 * 154 * Shared namespaces can be isolated or regular. Note that they do not inherit the search path nor 155 * permitted_path from the caller's namespace. 156 */ 157 ANDROID_NAMESPACE_TYPE_SHARED = 2, 158 159 /* This flag instructs linker to enable grey-list workaround for the namespace. 160 * See http://b/26394120 for details. 161 */ 162 ANDROID_NAMESPACE_TYPE_GREYLIST_ENABLED = 0x08000000, 163 164 ANDROID_NAMESPACE_TYPE_SHARED_ISOLATED = ANDROID_NAMESPACE_TYPE_SHARED | 165 ANDROID_NAMESPACE_TYPE_ISOLATED, 166 }; 167 168 bool init_anonymous_namespace(const char* shared_lib_sonames, const char* library_search_path); 169 android_namespace_t* create_namespace(const void* caller_addr, 170 const char* name, 171 const char* ld_library_path, 172 const char* default_library_path, 173 uint64_t type, 174 const char* permitted_when_isolated_path, 175 android_namespace_t* parent_namespace); 176 177 bool link_namespaces(android_namespace_t* namespace_from, 178 android_namespace_t* namespace_to, 179 const char* shared_lib_sonames); 180 181 android_namespace_t* get_exported_namespace(const char* name); 182 183 #endif 184