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 "private/libc_logging.h" 42 #include "linked_list.h" 43 #include "linker_common_types.h" 44 #include "linker_logger.h" 45 #include "linker_soinfo.h" 46 47 #include <string> 48 #include <vector> 49 50 #if defined(__LP64__) 51 #define ELFW(what) ELF64_ ## what 52 #else 53 #define ELFW(what) ELF32_ ## what 54 #endif 55 56 // mips64 interprets Elf64_Rel structures' r_info field differently. 57 // bionic (like other C libraries) has macros that assume regular ELF files, 58 // but the dynamic linker needs to be able to load mips64 ELF files. 59 #if defined(__mips__) && defined(__LP64__) 60 #undef ELF64_R_SYM 61 #undef ELF64_R_TYPE 62 #undef ELF64_R_INFO 63 #define ELF64_R_SYM(info) (((info) >> 0) & 0xffffffff) 64 #define ELF64_R_SSYM(info) (((info) >> 32) & 0xff) 65 #define ELF64_R_TYPE3(info) (((info) >> 40) & 0xff) 66 #define ELF64_R_TYPE2(info) (((info) >> 48) & 0xff) 67 #define ELF64_R_TYPE(info) (((info) >> 56) & 0xff) 68 #endif 69 70 #define SUPPORTED_DT_FLAGS_1 (DF_1_NOW | DF_1_GLOBAL | DF_1_NODELETE | DF_1_PIE) 71 72 // Class used construct version dependency graph. 73 class VersionTracker { 74 public: 75 VersionTracker() = default; 76 bool init(const soinfo* si_from); 77 78 const version_info* get_version_info(ElfW(Versym) source_symver) const; 79 private: 80 bool init_verneed(const soinfo* si_from); 81 bool init_verdef(const soinfo* si_from); 82 void add_version_info(size_t source_index, ElfW(Word) elf_hash, 83 const char* ver_name, const soinfo* target_si); 84 85 std::vector<version_info> version_infos; 86 87 DISALLOW_COPY_AND_ASSIGN(VersionTracker); 88 }; 89 90 bool soinfo_do_lookup(soinfo* si_from, const char* name, const version_info* vi, 91 soinfo** si_found_in, const soinfo_list_t& global_group, 92 const soinfo_list_t& local_group, const ElfW(Sym)** symbol); 93 94 enum RelocationKind { 95 kRelocAbsolute = 0, 96 kRelocRelative, 97 kRelocCopy, 98 kRelocSymbol, 99 kRelocMax 100 }; 101 102 void count_relocation(RelocationKind kind); 103 104 soinfo* get_libdl_info(const char* linker_path); 105 106 soinfo* find_containing_library(const void* p); 107 108 void do_android_get_LD_LIBRARY_PATH(char*, size_t); 109 void do_android_update_LD_LIBRARY_PATH(const char* ld_library_path); 110 void* do_dlopen(const char* name, 111 int flags, 112 const android_dlextinfo* extinfo, 113 const void* caller_addr); 114 115 int do_dlclose(void* handle); 116 117 int do_dl_iterate_phdr(int (*cb)(dl_phdr_info* info, size_t size, void* data), void* data); 118 119 #if defined(__arm__) 120 _Unwind_Ptr do_dl_unwind_find_exidx(_Unwind_Ptr pc, int* pcount); 121 #endif 122 123 bool do_dlsym(void* handle, const char* sym_name, 124 const char* sym_ver, 125 const void* caller_addr, 126 void** symbol); 127 128 int do_dladdr(const void* addr, Dl_info* info); 129 130 // void ___cfi_slowpath(uint64_t CallSiteTypeId, void *Ptr, void *Ret); 131 // void ___cfi_slowpath_diag(uint64_t CallSiteTypeId, void *Ptr, void *DiagData, void *Ret); 132 void ___cfi_fail(uint64_t CallSiteTypeId, void* Ptr, void *DiagData, void *Ret); 133 134 void set_application_target_sdk_version(uint32_t target); 135 uint32_t get_application_target_sdk_version(); 136 137 enum { 138 /* A regular namespace is the namespace with a custom search path that does 139 * not impose any restrictions on the location of native libraries. 140 */ 141 ANDROID_NAMESPACE_TYPE_REGULAR = 0, 142 143 /* An isolated namespace requires all the libraries to be on the search path 144 * or under permitted_when_isolated_path. The search path is the union of 145 * ld_library_path and default_library_path. 146 */ 147 ANDROID_NAMESPACE_TYPE_ISOLATED = 1, 148 149 /* The shared namespace clones the list of libraries of the caller namespace upon creation 150 * which means that they are shared between namespaces - the caller namespace and the new one 151 * will use the same copy of a library if it was loaded prior to android_create_namespace call. 152 * 153 * Note that libraries loaded after the namespace is created will not be shared. 154 * 155 * Shared namespaces can be isolated or regular. Note that they do not inherit the search path nor 156 * permitted_path from the caller's namespace. 157 */ 158 ANDROID_NAMESPACE_TYPE_SHARED = 2, 159 160 /* This flag instructs linker to enable grey-list workaround for the namespace. 161 * See http://b/26394120 for details. 162 */ 163 ANDROID_NAMESPACE_TYPE_GREYLIST_ENABLED = 0x08000000, 164 165 ANDROID_NAMESPACE_TYPE_SHARED_ISOLATED = ANDROID_NAMESPACE_TYPE_SHARED | 166 ANDROID_NAMESPACE_TYPE_ISOLATED, 167 }; 168 169 bool init_anonymous_namespace(const char* shared_lib_sonames, const char* library_search_path); 170 android_namespace_t* create_namespace(const void* caller_addr, 171 const char* name, 172 const char* ld_library_path, 173 const char* default_library_path, 174 uint64_t type, 175 const char* permitted_when_isolated_path, 176 android_namespace_t* parent_namespace); 177 178 bool link_namespaces(android_namespace_t* namespace_from, 179 android_namespace_t* namespace_to, 180 const char* shared_lib_sonames); 181 182 android_namespace_t* get_exported_namespace(const char* name); 183 184 #endif 185