Introducing linker namespaces

Bug: http://b/22548808
Change-Id: Ia3af3c0a167f1d16447a3d83bb045d143319b1e1
This commit is contained in:
Dmitriy Ivanov 2015-10-29 17:01:24 -07:00
parent ffe5c24c86
commit 42d5fcb9f4
26 changed files with 1122 additions and 152 deletions

View file

@ -98,6 +98,11 @@ enum {
*/
ANDROID_DLEXT_LOAD_AT_FIXED_ADDRESS = 0x100,
/* This flag used to load library in a different namespace. The namespace is
* specified in library_namespace.
*/
ANDROID_DLEXT_USE_NAMESPACE = 0x200,
/* Mask of valid bits */
ANDROID_DLEXT_VALID_FLAG_BITS = ANDROID_DLEXT_RESERVED_ADDRESS |
ANDROID_DLEXT_RESERVED_ADDRESS_HINT |
@ -107,9 +112,12 @@ enum {
ANDROID_DLEXT_USE_LIBRARY_FD_OFFSET |
ANDROID_DLEXT_FORCE_LOAD |
ANDROID_DLEXT_FORCE_FIXED_VADDR |
ANDROID_DLEXT_LOAD_AT_FIXED_ADDRESS,
ANDROID_DLEXT_LOAD_AT_FIXED_ADDRESS |
ANDROID_DLEXT_USE_NAMESPACE,
};
struct android_namespace_t;
typedef struct {
uint64_t flags;
void* reserved_addr;
@ -117,10 +125,40 @@ typedef struct {
int relro_fd;
int library_fd;
off64_t library_fd_offset;
struct android_namespace_t* library_namespace;
} android_dlextinfo;
extern void* android_dlopen_ext(const char* filename, int flag, const android_dlextinfo* extinfo);
/*
* Initializes public namespace. The path is the list of sonames
* separated by colon. Example: "libc.so:libm.so:libdl.so".
*
* The libraries in this list should be loaded prior to this call.
*/
extern bool android_init_public_namespace(const char* path);
/*
* Creates new linker namespace.
* ld_library_path and default_library_path represent the search path
* for the libraries in the namespace.
*
* The libraries in the namespace are searched by folowing order:
* 1. ld_library_path (Think of this as namespace-local LD_LIBRARY_PATH)
* 2. In directories specified by DT_RUNPATH of the "needed by" binary.
* 3. deault_library_path (This of this as namespace-local default library path)
*
* When is_isolated is true the resulted namespace requires all of the libraries
* to be on the search path; the search_path is ld_library_path:default_library_path.
*
* If a library or any of its dependencies are outside of the search path and not
* part of the public namespace dlopen will fail.
*/
extern struct android_namespace_t* android_create_namespace(const char* name,
const char* ld_library_path,
const char* default_library_path,
bool is_isolated);
__END_DECLS
#endif /* __ANDROID_DLEXT_H__ */

View file

@ -14,10 +14,16 @@ LIBC {
*;
};
LIBC_N {
global:
android_init_public_namespace;
android_create_namespace;
} LIBC;
LIBC_PRIVATE {
global:
android_get_application_target_sdk_version;
android_set_application_target_sdk_version;
android_get_LD_LIBRARY_PATH;
android_update_LD_LIBRARY_PATH;
} LIBC;
} LIBC_N;

View file

@ -13,10 +13,16 @@ LIBC {
*;
};
LIBC_N {
global:
android_init_public_namespace;
android_create_namespace;
} LIBC;
LIBC_PRIVATE {
global:
android_get_application_target_sdk_version;
android_set_application_target_sdk_version;
android_get_LD_LIBRARY_PATH;
android_update_LD_LIBRARY_PATH;
} LIBC;
} LIBC_N;

View file

@ -33,12 +33,26 @@ int dlclose(void* handle __unused) { return 0; }
_Unwind_Ptr dl_unwind_find_exidx(_Unwind_Ptr pc __unused, int* pcount __unused) { return 0; }
#endif
int dl_iterate_phdr(int (*cb)(struct dl_phdr_info* info, size_t size, void* data) __unused, void* data __unused) { return 0; }
int dl_iterate_phdr(int (*cb)(struct dl_phdr_info* info, size_t size, void* data) __unused,
void* data __unused) {
return 0;
}
void android_get_LD_LIBRARY_PATH(char* buffer __unused, size_t buffer_size __unused) { }
void android_update_LD_LIBRARY_PATH(const char* ld_library_path __unused) { }
void* android_dlopen_ext(const char* filename __unused, int flag __unused, const android_dlextinfo* extinfo __unused) { return 0; }
void* android_dlopen_ext(const char* filename __unused, int flag __unused,
const android_dlextinfo* extinfo __unused) {
return 0;
}
void android_set_application_target_sdk_version(uint32_t target __unused) { }
uint32_t android_get_application_target_sdk_version() { return 0; }
bool android_init_public_namespace(const char* paths __unused) { return false; }
struct android_namespace_t* android_create_namespace(const char* name __unused,
const char* ld_library_path __unused,
const char* default_library_path __unused,
bool isolated __unused) {
return 0;
}

View file

@ -28,10 +28,16 @@ LIBC {
*;
};
LIBC_N {
global:
android_init_public_namespace;
android_create_namespace;
} LIBC;
LIBC_PRIVATE {
global:
android_get_application_target_sdk_version;
android_set_application_target_sdk_version;
android_get_LD_LIBRARY_PATH;
android_update_LD_LIBRARY_PATH;
} LIBC;
} LIBC_N;

View file

@ -13,10 +13,16 @@ LIBC {
*;
};
LIBC_N {
global:
android_init_public_namespace;
android_create_namespace;
} LIBC;
LIBC_PRIVATE {
global:
android_get_application_target_sdk_version;
android_set_application_target_sdk_version;
android_get_LD_LIBRARY_PATH;
android_update_LD_LIBRARY_PATH;
} LIBC;
} LIBC_N;

View file

@ -13,10 +13,16 @@ LIBC {
*;
};
LIBC_N {
global:
android_init_public_namespace;
android_create_namespace;
} LIBC;
LIBC_PRIVATE {
global:
android_get_application_target_sdk_version;
android_set_application_target_sdk_version;
android_get_LD_LIBRARY_PATH;
android_update_LD_LIBRARY_PATH;
} LIBC;
} LIBC_N;

View file

@ -13,10 +13,16 @@ LIBC {
*;
};
LIBC_N {
global:
android_init_public_namespace;
android_create_namespace;
} LIBC;
LIBC_PRIVATE {
global:
android_get_application_target_sdk_version;
android_set_application_target_sdk_version;
android_get_LD_LIBRARY_PATH;
android_update_LD_LIBRARY_PATH;
} LIBC;
} LIBC_N;

View file

@ -13,10 +13,16 @@ LIBC {
*;
};
LIBC_N {
global:
android_init_public_namespace;
android_create_namespace;
} LIBC;
LIBC_PRIVATE {
global:
android_get_application_target_sdk_version;
android_set_application_target_sdk_version;
android_get_LD_LIBRARY_PATH;
android_update_LD_LIBRARY_PATH;
} LIBC;
} LIBC_N;

View file

@ -9,12 +9,12 @@ LOCAL_SRC_FILES := \
dlfcn.cpp \
linker.cpp \
linker_allocator.cpp \
linker_sdk_versions.cpp \
linker_block_allocator.cpp \
linker_libc_support.c \
linker_mapped_file_fragment.cpp \
linker_memory.cpp \
linker_phdr.cpp \
linker_sdk_versions.cpp \
linker_utils.cpp \
rt.cpp \

View file

@ -108,9 +108,16 @@ void* dlsym(void* handle, const char* symbol) {
const ElfW(Sym)* sym = nullptr;
void* caller_addr = __builtin_return_address(0);
soinfo* caller = find_containing_library(caller_addr);
if (caller == nullptr) {
char buf[256];
__libc_format_buffer(buf, sizeof(buf), "dlsym couldn't locate its caller address=%p; "
"the caller was code not loaded by the dynamic linker", caller_addr);
__bionic_format_dlerror(buf, nullptr);
return nullptr;
}
if (handle == RTLD_DEFAULT || handle == RTLD_NEXT) {
sym = dlsym_linear_lookup(symbol, &found, caller, handle);
sym = dlsym_linear_lookup(caller->get_namespace(), symbol, &found, caller, handle);
} else {
sym = dlsym_handle_lookup(reinterpret_cast<soinfo*>(handle), &found, symbol);
}
@ -177,6 +184,30 @@ uint32_t android_get_application_target_sdk_version() {
return get_application_target_sdk_version();
}
bool android_init_public_namespace(const char* path) {
ScopedPthreadMutexLocker locker(&g_dl_mutex);
bool success = init_public_namespace(path);
if (!success) {
__bionic_format_dlerror("android_init_public_namespace failed", linker_get_error_buffer());
}
return success;
}
android_namespace_t* android_create_namespace(const char* name, const char* ld_library_path,
const char* default_library_path, bool is_isolated) {
ScopedPthreadMutexLocker locker(&g_dl_mutex);
android_namespace_t* result = create_namespace(name, ld_library_path,
default_library_path, is_isolated);
if (result == nullptr) {
__bionic_format_dlerror("android_create_namespace failed", linker_get_error_buffer());
}
return result;
}
// name_offset: starting index of the name in libdl_info.strtab
#define ELF32_SYM_INITIALIZER(name_offset, value, shndx) \
{ name_offset, \
@ -203,11 +234,11 @@ static const char ANDROID_LIBDL_STRTAB[] =
// 00000000001 1111111112222222222 3333333333444444444455555555556666666666777 777777788888888889999999999
// 01234567890 1234567890123456789 0123456789012345678901234567890123456789012 345678901234567890123456789
"erate_phdr\0android_dlopen_ext\0android_set_application_target_sdk_version\0android_get_application_tar"
// 0000000000111111
// 0123456789012345
"get_sdk_version\0"
// 0000000000111111 111122222222223333333333444444 4444555555555566666666667
// 0123456789012345 678901234567890123456789012345 6789012345678901234567890
"get_sdk_version\0android_init_public_namespace\0android_create_namespace\0"
#if defined(__arm__)
// 216
// 271
"dl_unwind_find_exidx\0"
#endif
;
@ -229,8 +260,10 @@ static ElfW(Sym) g_libdl_symtab[] = {
ELFW(SYM_INITIALIZER)(111, &android_dlopen_ext, 1),
ELFW(SYM_INITIALIZER)(130, &android_set_application_target_sdk_version, 1),
ELFW(SYM_INITIALIZER)(173, &android_get_application_target_sdk_version, 1),
ELFW(SYM_INITIALIZER)(216, &android_init_public_namespace, 1),
ELFW(SYM_INITIALIZER)(246, &android_create_namespace, 1),
#if defined(__arm__)
ELFW(SYM_INITIALIZER)(216, &dl_unwind_find_exidx, 1),
ELFW(SYM_INITIALIZER)(271, &dl_unwind_find_exidx, 1),
#endif
};
@ -247,18 +280,20 @@ static ElfW(Sym) g_libdl_symtab[] = {
// Note that adding any new symbols here requires stubbing them out in libdl.
static unsigned g_libdl_buckets[1] = { 1 };
#if defined(__arm__)
static unsigned g_libdl_chains[] = { 0, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 0 };
static unsigned g_libdl_chains[] = { 0, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 0 };
#else
static unsigned g_libdl_chains[] = { 0, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 0 };
static unsigned g_libdl_chains[] = { 0, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 0 };
#endif
static uint8_t __libdl_info_buf[sizeof(soinfo)] __attribute__((aligned(8)));
static soinfo* __libdl_info = nullptr;
extern android_namespace_t g_default_namespace;
// This is used by the dynamic linker. Every process gets these symbols for free.
soinfo* get_libdl_info() {
if (__libdl_info == nullptr) {
__libdl_info = new (__libdl_info_buf) soinfo("libdl.so", nullptr, 0, RTLD_GLOBAL);
__libdl_info = new (__libdl_info_buf) soinfo(&g_default_namespace, "libdl.so", nullptr, 0, RTLD_GLOBAL);
__libdl_info->flags_ |= FLAG_LINKED;
__libdl_info->strtab_ = ANDROID_LIBDL_STRTAB;
__libdl_info->symtab_ = g_libdl_symtab;

View file

@ -25,12 +25,49 @@ struct LinkedListEntry {
T* element;
};
// ForwardInputIterator
template<typename T>
class LinkedListIterator {
public:
LinkedListIterator() : entry_(nullptr) {}
LinkedListIterator(const LinkedListIterator<T>& that) : entry_(that.entry_) {}
explicit LinkedListIterator(LinkedListEntry<T>* entry) : entry_(entry) {}
LinkedListIterator<T>& operator=(const LinkedListIterator<T>& that) {
entry_ = that.entry_;
return *this;
}
LinkedListIterator<T>& operator++() {
entry_ = entry_->next;
return *this;
}
T* operator*() {
return entry_->element;
}
bool operator==(const LinkedListIterator<T>& that) const {
return entry_ == that.entry_;
}
bool operator!=(const LinkedListIterator<T>& that) const {
return entry_ != that.entry_;
}
private:
LinkedListEntry<T> *entry_;
};
/*
* Represents linked list of objects of type T
*/
template<typename T, typename Allocator>
class LinkedList {
public:
typedef LinkedListIterator<T> iterator;
typedef T* value_type;
LinkedList() : head_(nullptr), tail_(nullptr) {}
~LinkedList() {
clear();
@ -133,6 +170,7 @@ class LinkedList {
}
Allocator::free(e);
e = next;
} else {
p = e;
@ -152,6 +190,24 @@ class LinkedList {
return nullptr;
}
iterator begin() {
return iterator(head_);
}
iterator end() {
return iterator(nullptr);
}
iterator find(T* value) {
for (LinkedListEntry<T>* e = head_; e != nullptr; e = e->next) {
if (e->element == value) {
return iterator(e);
}
}
return end();
}
size_t copy_to_array(T* array[], size_t array_length) const {
size_t sz = 0;
for (LinkedListEntry<T>* e = head_; sz < array_length && e != nullptr; e = e->next) {

View file

@ -70,11 +70,55 @@ extern void __libc_init_AT_SECURE(KernelArgumentBlock&);
#undef ELF_ST_TYPE
#define ELF_ST_TYPE(x) (static_cast<uint32_t>(x) & 0xf)
struct android_namespace_t {
public:
android_namespace_t() : name_(nullptr), is_isolated_(false) {}
const char* get_name() const { return name_; }
void set_name(const char* name) { name_ = name; }
bool is_isolated() const { return is_isolated_; }
void set_isolated(bool isolated) { is_isolated_ = isolated; }
const std::vector<std::string>& get_ld_library_paths() const {
return ld_library_paths_;
}
void set_ld_library_paths(std::vector<std::string>&& library_paths) {
ld_library_paths_ = library_paths;
}
const std::vector<std::string>& get_default_library_paths() const {
return default_library_paths_;
}
void set_default_library_paths(std::vector<std::string>&& library_paths) {
default_library_paths_ = library_paths;
}
soinfo::soinfo_list_t& soinfo_list() { return soinfo_list_; }
// For isolated namespaces - checks if the file is on the search path;
// always returns true for not isolated namespace.
bool is_accessible(const std::string& path);
private:
const char* name_;
bool is_isolated_;
std::vector<std::string> ld_library_paths_;
std::vector<std::string> default_library_paths_;
soinfo::soinfo_list_t soinfo_list_;
DISALLOW_COPY_AND_ASSIGN(android_namespace_t);
};
android_namespace_t g_default_namespace;
static ElfW(Addr) get_elf_exec_load_bias(const ElfW(Ehdr)* elf);
static LinkerTypeAllocator<soinfo> g_soinfo_allocator;
static LinkerTypeAllocator<LinkedListEntry<soinfo>> g_soinfo_links_allocator;
static LinkerTypeAllocator<android_namespace_t> g_namespace_allocator;
static soinfo* solist;
static soinfo* sonext;
static soinfo* somain; // main process, always the one after libdl_info
@ -107,14 +151,15 @@ static const char* const kAsanDefaultLdPaths[] = {
static const ElfW(Versym) kVersymNotNeeded = 0;
static const ElfW(Versym) kVersymGlobal = 1;
static const char* const kZipFileSeparator = "!/";
static const char* const* g_default_ld_paths;
static std::vector<std::string> g_ld_library_paths;
static std::vector<std::string> g_ld_preload_names;
static std::vector<soinfo*> g_ld_preloads;
static bool g_public_namespace_initialized;
static soinfo::soinfo_list_t g_public_namespace;
__LIBC_HIDDEN__ int g_ld_debug_verbosity;
__LIBC_HIDDEN__ abort_msg_t* g_abort_message = nullptr; // For debuggerd.
@ -247,6 +292,26 @@ void notify_gdb_of_libraries() {
rtld_db_dlactivity();
}
bool android_namespace_t::is_accessible(const std::string& file) {
if (!is_isolated_) {
return true;
}
for (const auto& dir : ld_library_paths_) {
if (file_is_in_dir(file, dir)) {
return true;
}
}
for (const auto& dir : default_library_paths_) {
if (file_is_in_dir(file, dir)) {
return true;
}
}
return false;
}
LinkedListEntry<soinfo>* SoinfoListAllocator::alloc() {
return g_soinfo_links_allocator.alloc();
}
@ -255,18 +320,22 @@ void SoinfoListAllocator::free(LinkedListEntry<soinfo>* entry) {
g_soinfo_links_allocator.free(entry);
}
static soinfo* soinfo_alloc(const char* name, struct stat* file_stat,
off64_t file_offset, uint32_t rtld_flags) {
static soinfo* soinfo_alloc(android_namespace_t* ns, const char* name,
struct stat* file_stat, off64_t file_offset,
uint32_t rtld_flags) {
if (strlen(name) >= PATH_MAX) {
DL_ERR("library name \"%s\" too long", name);
return nullptr;
}
soinfo* si = new (g_soinfo_allocator.alloc()) soinfo(name, file_stat, file_offset, rtld_flags);
soinfo* si = new (g_soinfo_allocator.alloc()) soinfo(ns, name, file_stat,
file_offset, rtld_flags);
sonext->next = si;
sonext = si;
ns->soinfo_list().push_back(si);
TRACE("name %s: allocated soinfo @ %p", name, si);
return si;
}
@ -307,33 +376,130 @@ static void soinfo_free(soinfo* si) {
sonext = prev;
}
// remove from the namespace
si->get_namespace()->soinfo_list().remove_if([&](soinfo* candidate) {
return si == candidate;
});
si->~soinfo();
g_soinfo_allocator.free(si);
}
static void parse_path(const char* path, const char* delimiters,
// For every path element this function checks of it exists, and is a directory,
// and normalizes it:
// 1. For regular path it converts it to realpath()
// 2. For path in a zip file it uses realpath on the zipfile
// normalizes entry name by calling normalize_path function.
static void resolve_paths(std::vector<std::string>& paths,
std::vector<std::string>* resolved_paths) {
resolved_paths->clear();
for (const auto& path : paths) {
char resolved_path[PATH_MAX];
const char* original_path = path.c_str();
if (realpath(original_path, resolved_path) != nullptr) {
struct stat s;
if (stat(resolved_path, &s) == 0) {
if (S_ISDIR(s.st_mode)) {
resolved_paths->push_back(resolved_path);
} else {
DL_WARN("Warning: \"%s\" is not a directory (excluding from path)", resolved_path);
continue;
}
} else {
DL_WARN("Warning: cannot stat file \"%s\": %s", resolved_path, strerror(errno));
continue;
}
} else {
std::string zip_path;
std::string entry_path;
std::string normalized_path;
if (!normalize_path(original_path, &normalized_path)) {
DL_WARN("Warning: unable to normalize \"%s\"", original_path);
continue;
}
if (parse_zip_path(normalized_path.c_str(), &zip_path, &entry_path)) {
if (realpath(zip_path.c_str(), resolved_path) == nullptr) {
DL_WARN("Warning: unable to resolve \"%s\": %s", zip_path.c_str(), strerror(errno));
continue;
}
ZipArchiveHandle handle = nullptr;
if (OpenArchive(resolved_path, &handle) != 0) {
DL_WARN("Warning: unable to open zip archive: %s", resolved_path);
continue;
}
// Check if zip-file has a dir with entry_path name
void* cookie = nullptr;
std::string prefix_str = entry_path + "/";
ZipString prefix(prefix_str.c_str());
ZipEntry out_data;
ZipString out_name;
int32_t error_code;
if ((error_code = StartIteration(handle, &cookie, &prefix, nullptr)) != 0) {
DL_WARN("Unable to iterate over zip-archive entries \"%s\";"
" error code: %d", zip_path.c_str(), error_code);
continue;
}
if (Next(cookie, &out_data, &out_name) != 0) {
DL_WARN("Unable to find entries starting with \"%s\" in \"%s\"",
prefix_str.c_str(), zip_path.c_str());
continue;
}
auto zip_guard = make_scope_guard([&]() {
if (cookie != nullptr) {
EndIteration(cookie);
}
CloseArchive(handle);
});
resolved_paths->push_back(std::string(resolved_path) + kZipFileSeparator + entry_path);
}
}
}
}
static void split_path(const char* path, const char* delimiters,
std::vector<std::string>* paths) {
paths->clear();
if (path != nullptr) {
*paths = android::base::Split(path, delimiters);
}
}
static void parse_path(const char* path, const char* delimiters,
std::vector<std::string>* resolved_paths) {
std::vector<std::string> paths;
split_path(path, delimiters, &paths);
resolve_paths(paths, resolved_paths);
}
static void parse_LD_LIBRARY_PATH(const char* path) {
parse_path(path, ":", &g_ld_library_paths);
std::vector<std::string> ld_libary_paths;
parse_path(path, ":", &ld_libary_paths);
g_default_namespace.set_ld_library_paths(std::move(ld_libary_paths));
}
void soinfo::set_dt_runpath(const char* path) {
if (!has_min_version(2)) {
if (!has_min_version(3)) {
return;
}
parse_path(path, ":", &dt_runpath_);
std::vector<std::string> runpaths;
split_path(path, ":", &runpaths);
std::string origin = dirname(get_realpath());
// FIXME: add $LIB and $PLATFORM.
std::pair<std::string, std::string> substs[] = {{"ORIGIN", origin}};
for (auto&& s : dt_runpath_) {
for (auto&& s : runpaths) {
size_t pos = 0;
while (pos < s.size()) {
pos = s.find("$", pos);
@ -356,11 +522,16 @@ void soinfo::set_dt_runpath(const char* path) {
++pos;
}
}
resolve_paths(runpaths, &dt_runpath_);
}
static void parse_LD_PRELOAD(const char* path) {
g_ld_preload_names.clear();
if (path != nullptr) {
// We have historically supported ':' as well as ' ' in LD_PRELOAD.
parse_path(path, " :", &g_ld_preload_names);
g_ld_preload_names = android::base::Split(path, " :");
}
}
static bool realpath_fd(int fd, std::string* realpath) {
@ -688,8 +859,9 @@ bool soinfo::elf_lookup(SymbolName& symbol_name,
return true;
}
soinfo::soinfo(const char* realpath, const struct stat* file_stat,
off64_t file_offset, int rtld_flags) {
soinfo::soinfo(android_namespace_t* ns, const char* realpath,
const struct stat* file_stat, off64_t file_offset,
int rtld_flags) {
memset(this, 0, sizeof(*this));
if (realpath != nullptr) {
@ -706,6 +878,7 @@ soinfo::soinfo(const char* realpath, const struct stat* file_stat,
}
this->rtld_flags_ = rtld_flags;
this->namespace_ = ns;
}
@ -857,6 +1030,7 @@ class ProtectedDataGuard {
void protect_data(int protection) {
g_soinfo_allocator.protect_all(protection);
g_soinfo_links_allocator.protect_all(protection);
g_namespace_allocator.protect_all(protection);
}
static size_t ref_count_;
@ -1096,7 +1270,7 @@ const ElfW(Sym)* dlsym_handle_lookup(soinfo* si, soinfo** found, const char* nam
// libraries and they are loaded in breath-first (correct) order we can just execute
// dlsym(RTLD_DEFAULT, ...); instead of doing two stage lookup.
if (si == somain) {
return dlsym_linear_lookup(name, found, nullptr, RTLD_DEFAULT);
return dlsym_linear_lookup(&g_default_namespace, name, found, nullptr, RTLD_DEFAULT);
}
SymbolName symbol_name(name);
@ -1108,24 +1282,29 @@ const ElfW(Sym)* dlsym_handle_lookup(soinfo* si, soinfo** found, const char* nam
beginning of the global solist. Otherwise the search starts at the
specified soinfo (for RTLD_NEXT).
*/
const ElfW(Sym)* dlsym_linear_lookup(const char* name,
const ElfW(Sym)* dlsym_linear_lookup(android_namespace_t* ns,
const char* name,
soinfo** found,
soinfo* caller,
void* handle) {
SymbolName symbol_name(name);
soinfo* start = solist;
soinfo::soinfo_list_t& soinfo_list = ns->soinfo_list();
soinfo::soinfo_list_t::iterator start = soinfo_list.begin();
if (handle == RTLD_NEXT) {
if (caller == nullptr) {
return nullptr;
} else {
start = caller->next;
soinfo::soinfo_list_t::iterator it = soinfo_list.find(caller);
CHECK (it != soinfo_list.end());
start = ++it;
}
}
const ElfW(Sym)* s = nullptr;
for (soinfo* si = start; si != nullptr; si = si->next) {
for (soinfo::soinfo_list_t::iterator it = start, end = soinfo_list.end(); it != end; ++it) {
soinfo* si = *it;
// Do not skip RTLD_LOCAL libraries in dlsym(RTLD_DEFAULT, ...)
// if the library is opened by application with target api level <= 22
// See http://b/21565766
@ -1337,35 +1516,13 @@ static bool format_path(char* buf, size_t buf_size, const char* path, const char
return true;
}
static int open_library_on_default_path(const char* name, off64_t* file_offset, std::string* realpath) {
for (size_t i = 0; g_default_ld_paths[i] != nullptr; ++i) {
char buf[512];
if (!format_path(buf, sizeof(buf), g_default_ld_paths[i], name)) {
continue;
}
int fd = TEMP_FAILURE_RETRY(open(buf, O_RDONLY | O_CLOEXEC));
if (fd != -1) {
*file_offset = 0;
if (!realpath_fd(fd, realpath)) {
PRINT("warning: unable to get realpath for the library \"%s\". Will use given path.", buf);
*realpath = buf;
}
return fd;
}
}
return -1;
}
static int open_library_on_paths(ZipArchiveCache* zip_archive_cache,
const char* name, off64_t* file_offset,
const std::vector<std::string>& paths,
std::string* realpath) {
for (const auto& path_str : paths) {
for (const auto& path : paths) {
char buf[512];
const char* const path = path_str.c_str();
if (!format_path(buf, sizeof(buf), path, name)) {
if (!format_path(buf, sizeof(buf), path.c_str(), name)) {
continue;
}
@ -1393,21 +1550,22 @@ static int open_library_on_paths(ZipArchiveCache* zip_archive_cache,
return -1;
}
static int open_library(ZipArchiveCache* zip_archive_cache,
static int open_library(android_namespace_t* ns,
ZipArchiveCache* zip_archive_cache,
const char* name, soinfo *needed_by,
off64_t* file_offset, std::string* realpath) {
TRACE("[ opening %s ]", name);
// If the name contains a slash, we should attempt to open it directly and not search the paths.
if (strchr(name, '/') != nullptr) {
int fd = -1;
if (strstr(name, kZipFileSeparator) != nullptr) {
int fd = open_library_in_zipfile(zip_archive_cache, name, file_offset, realpath);
if (fd != -1) {
return fd;
}
fd = open_library_in_zipfile(zip_archive_cache, name, file_offset, realpath);
}
int fd = TEMP_FAILURE_RETRY(open(name, O_RDONLY | O_CLOEXEC));
if (fd == -1) {
fd = TEMP_FAILURE_RETRY(open(name, O_RDONLY | O_CLOEXEC));
if (fd != -1) {
*file_offset = 0;
if (!realpath_fd(fd, realpath)) {
@ -1415,17 +1573,26 @@ static int open_library(ZipArchiveCache* zip_archive_cache,
*realpath = name;
}
}
}
if (fd != -1 && !ns->is_accessible(*realpath)) {
fd = -1;
}
return fd;
}
// Otherwise we try LD_LIBRARY_PATH first, and fall back to the built-in well known paths.
int fd = open_library_on_paths(zip_archive_cache, name, file_offset, g_ld_library_paths, realpath);
// Otherwise we try LD_LIBRARY_PATH first, and fall back to the default library path
int fd = open_library_on_paths(zip_archive_cache, name, file_offset, ns->get_ld_library_paths(), realpath);
if (fd == -1 && needed_by != nullptr) {
fd = open_library_on_paths(zip_archive_cache, name, file_offset, needed_by->get_dt_runpath(), realpath);
// Check if the library is accessible
if (fd != -1 && !ns->is_accessible(*realpath)) {
fd = -1;
}
}
if (fd == -1) {
fd = open_library_on_default_path(name, file_offset, realpath);
fd = open_library_on_paths(zip_archive_cache, name, file_offset, ns->get_default_library_paths(), realpath);
}
return fd;
@ -1464,7 +1631,8 @@ static void for_each_dt_needed(const ElfReader& elf_reader, F action) {
}
}
static bool load_library(LoadTask* task,
static bool load_library(android_namespace_t* ns,
LoadTask* task,
LoadTaskList* load_tasks,
int rtld_flags,
const std::string& realpath) {
@ -1495,26 +1663,38 @@ static bool load_library(LoadTask* task,
// Check for symlink and other situations where
// file can have different names, unless ANDROID_DLEXT_FORCE_LOAD is set
if (extinfo == nullptr || (extinfo->flags & ANDROID_DLEXT_FORCE_LOAD) == 0) {
for (soinfo* si = solist; si != nullptr; si = si->next) {
if (si->get_st_dev() != 0 &&
auto predicate = [&](soinfo* si) {
return si->get_st_dev() != 0 &&
si->get_st_ino() != 0 &&
si->get_st_dev() == file_stat.st_dev &&
si->get_st_ino() == file_stat.st_ino &&
si->get_file_offset() == file_offset) {
si->get_file_offset() == file_offset;
};
soinfo* si = ns->soinfo_list().find_if(predicate);
// check public namespace
if (si == nullptr) {
si = g_public_namespace.find_if(predicate);
if (si != nullptr) {
ns->soinfo_list().push_back(si);
}
}
if (si != nullptr) {
TRACE("library \"%s\" is already loaded under different name/path \"%s\" - "
"will return existing soinfo", name, si->get_realpath());
task->set_soinfo(si);
return true;
}
}
}
if ((rtld_flags & RTLD_NOLOAD) != 0) {
DL_ERR("library \"%s\" wasn't loaded and RTLD_NOLOAD prevented it", name);
return false;
}
soinfo* si = soinfo_alloc(realpath.c_str(), &file_stat, file_offset, rtld_flags);
soinfo* si = soinfo_alloc(ns, realpath.c_str(), &file_stat, file_offset, rtld_flags);
if (si == nullptr) {
return false;
}
@ -1550,7 +1730,8 @@ static bool load_library(LoadTask* task,
}
static bool load_library(LoadTask* task,
static bool load_library(android_namespace_t* ns,
LoadTask* task,
ZipArchiveCache* zip_archive_cache,
LoadTaskList* load_tasks,
int rtld_flags) {
@ -1574,11 +1755,11 @@ static bool load_library(LoadTask* task,
task->set_fd(extinfo->library_fd, false);
task->set_file_offset(file_offset);
return load_library(task, load_tasks, rtld_flags, realpath);
return load_library(ns, task, load_tasks, rtld_flags, realpath);
}
// Open the file.
int fd = open_library(zip_archive_cache, name, needed_by, &file_offset, &realpath);
int fd = open_library(ns, zip_archive_cache, name, needed_by, &file_offset, &realpath);
if (fd == -1) {
DL_ERR("library \"%s\" not found", name);
return false;
@ -1587,14 +1768,15 @@ static bool load_library(LoadTask* task,
task->set_fd(fd, true);
task->set_file_offset(file_offset);
return load_library(task, load_tasks, rtld_flags, realpath);
return load_library(ns, task, load_tasks, rtld_flags, realpath);
}
// Returns true if library was found and false in 2 cases
// 1. The library was found but loaded under different target_sdk_version
// (*candidate != nullptr)
// 1. (for default namespace only) The library was found but loaded under different
// target_sdk_version (*candidate != nullptr)
// 2. The library was not found by soname (*candidate is nullptr)
static bool find_loaded_library_by_soname(const char* name, soinfo** candidate) {
static bool find_loaded_library_by_soname(android_namespace_t* ns,
const char* name, soinfo** candidate) {
*candidate = nullptr;
// Ignore filename with path.
@ -1604,7 +1786,7 @@ static bool find_loaded_library_by_soname(const char* name, soinfo** candidate)
uint32_t target_sdk_version = get_application_target_sdk_version();
for (soinfo* si = solist; si != nullptr; si = si->next) {
return !ns->soinfo_list().visit([&](soinfo* si) {
const char* soname = si->get_soname();
if (soname != nullptr && (strcmp(name, soname) == 0)) {
// If the library was opened under different target sdk version
@ -1614,36 +1796,52 @@ static bool find_loaded_library_by_soname(const char* name, soinfo** candidate)
// in any case.
bool is_libdl = si == solist;
if (is_libdl || (si->get_dt_flags_1() & DF_1_GLOBAL) != 0 ||
!si->is_linked() || si->get_target_sdk_version() == target_sdk_version) {
!si->is_linked() || si->get_target_sdk_version() == target_sdk_version ||
ns != &g_default_namespace) {
*candidate = si;
return true;
} else if (*candidate == nullptr) {
// for the different sdk version - remember the first library.
*candidate = si;
}
}
}
return false;
} else if (*candidate == nullptr) {
// for the different sdk version in the default namespace
// remember the first library.
*candidate = si;
}
}
static bool find_library_internal(LoadTask* task,
return true;
});
}
static bool find_library_internal(android_namespace_t* ns,
LoadTask* task,
ZipArchiveCache* zip_archive_cache,
LoadTaskList* load_tasks,
int rtld_flags) {
soinfo* candidate;
if (find_loaded_library_by_soname(task->get_name(), &candidate)) {
if (find_loaded_library_by_soname(ns, task->get_name(), &candidate)) {
task->set_soinfo(candidate);
return true;
}
if (ns != &g_default_namespace) {
// check public namespace
candidate = g_public_namespace.find_if([&](soinfo* si) {
return strcmp(task->get_name(), si->get_soname()) == 0;
});
if (candidate != nullptr) {
ns->soinfo_list().push_back(candidate);
task->set_soinfo(candidate);
return true;
}
}
// Library might still be loaded, the accurate detection
// of this fact is done by load_library.
TRACE("[ '%s' find_loaded_library_by_soname returned false (*candidate=%s@%p). Trying harder...]",
task->get_name(), candidate == nullptr ? "n/a" : candidate->get_realpath(), candidate);
if (load_library(task, zip_archive_cache, load_tasks, rtld_flags)) {
if (load_library(ns, task, zip_archive_cache, load_tasks, rtld_flags)) {
return true;
} else {
// In case we were unable to load the library but there
@ -1667,13 +1865,13 @@ static void soinfo_unload(soinfo* si);
//
// This group consists of the main executable, LD_PRELOADs
// and libraries with the DF_1_GLOBAL flag set.
static soinfo::soinfo_list_t make_global_group() {
static soinfo::soinfo_list_t make_global_group(android_namespace_t* ns) {
soinfo::soinfo_list_t global_group;
for (soinfo* si = somain; si != nullptr; si = si->next) {
ns->soinfo_list().for_each([&](soinfo* si) {
if ((si->get_dt_flags_1() & DF_1_GLOBAL) != 0) {
global_group.push_back(si);
}
}
});
return global_group;
}
@ -1690,7 +1888,8 @@ static void shuffle(std::vector<LoadTask*>* v) {
// not their transitive dependencies) as children of the start_with library.
// This is false when find_libraries is called for dlopen(), when newly loaded
// libraries must form a disjoint tree.
static bool find_libraries(soinfo* start_with,
static bool find_libraries(android_namespace_t* ns,
soinfo* start_with,
const char* const library_names[],
size_t library_names_count, soinfo* soinfos[],
std::vector<soinfo*>* ld_preloads,
@ -1707,7 +1906,7 @@ static bool find_libraries(soinfo* start_with,
}
// Construct global_group.
soinfo::soinfo_list_t global_group = make_global_group();
soinfo::soinfo_list_t global_group = make_global_group(ns);
// If soinfos array is null allocate one on stack.
// The array is needed in case of failure; for example
@ -1749,7 +1948,7 @@ static bool find_libraries(soinfo* start_with,
bool is_dt_needed = needed_by != nullptr && (needed_by != start_with || add_as_children);
task->set_extinfo(is_dt_needed ? nullptr : extinfo);
if(!find_library_internal(task, &zip_archive_cache, &load_tasks, rtld_flags)) {
if(!find_library_internal(ns, task, &zip_archive_cache, &load_tasks, rtld_flags)) {
return false;
}
@ -1850,14 +2049,15 @@ static bool find_libraries(soinfo* start_with,
return linked;
}
static soinfo* find_library(const char* name, int rtld_flags,
static soinfo* find_library(android_namespace_t* ns,
const char* name, int rtld_flags,
const android_dlextinfo* extinfo,
soinfo* needed_by) {
soinfo* si;
if (name == nullptr) {
si = somain;
} else if (!find_libraries(needed_by, &name, 1, &si, nullptr, 0, rtld_flags,
} else if (!find_libraries(ns, needed_by, &name, 1, &si, nullptr, 0, rtld_flags,
extinfo, /* add_as_children */ false)) {
return nullptr;
}
@ -1920,7 +2120,9 @@ static void soinfo_unload(soinfo* root) {
TRACE("deprecated (old format of soinfo): %s needs to unload %s",
si->get_realpath(), library_name);
soinfo* needed = find_library(library_name, RTLD_NOLOAD, nullptr, nullptr);
soinfo* needed = find_library(si->get_namespace(),
library_name, RTLD_NOLOAD, nullptr, nullptr);
if (needed != nullptr) {
// Not found: for example if symlink was deleted between dlopen and dlclose
// Since we cannot really handle errors at this point - print and continue.
@ -1992,6 +2194,9 @@ soinfo* do_dlopen(const char* name, int flags, const android_dlextinfo* extinfo,
DL_ERR("invalid flags to dlopen: %x", flags);
return nullptr;
}
android_namespace_t* ns = caller->get_namespace();
if (extinfo != nullptr) {
if ((extinfo->flags & ~(ANDROID_DLEXT_VALID_FLAG_BITS)) != 0) {
DL_ERR("invalid extended flags to android_dlopen_ext: 0x%" PRIx64, extinfo->flags);
@ -2011,13 +2216,22 @@ soinfo* do_dlopen(const char* name, int flags, const android_dlextinfo* extinfo,
"compatible with ANDROID_DLEXT_RESERVED_ADDRESS/ANDROID_DLEXT_RESERVED_ADDRESS_HINT");
return nullptr;
}
if ((extinfo->flags & ANDROID_DLEXT_USE_NAMESPACE) != 0) {
if (extinfo->library_namespace == nullptr) {
DL_ERR("ANDROID_DLEXT_USE_NAMESPACE is set but extinfo->library_namespace is null");
return nullptr;
}
ns = extinfo->library_namespace;
}
}
ProtectedDataGuard guard;
soinfo* si = find_library(name, flags, extinfo, caller);
soinfo* si = find_library(ns, name, flags, extinfo, caller);
if (si != nullptr) {
si->call_constructors();
}
return si;
}
@ -2026,6 +2240,67 @@ void do_dlclose(soinfo* si) {
soinfo_unload(si);
}
bool init_public_namespace(const char* libs) {
CHECK(libs != nullptr);
if (g_public_namespace_initialized) {
DL_ERR("Public namespace has already been initialized.");
return false;
}
std::vector<std::string> sonames = android::base::Split(libs, ":");
ProtectedDataGuard guard;
auto failure_guard = make_scope_guard([&]() {
g_public_namespace.clear();
});
soinfo* candidate;
for (const auto& soname : sonames) {
if (!find_loaded_library_by_soname(&g_default_namespace, soname.c_str(), &candidate)) {
DL_ERR("Error initializing public namespace: \"%s\" was not found"
" in the default namespace", soname.c_str());
return false;
}
candidate->set_nodelete();
g_public_namespace.push_back(candidate);
}
failure_guard.disable();
g_public_namespace_initialized = true;
return true;
}
android_namespace_t* create_namespace(const char* name,
const char* ld_library_path,
const char* default_library_path,
bool is_isolated) {
if (!g_public_namespace_initialized) {
DL_ERR("Cannot create namespace: public namespace is not initialized.");
return nullptr;
}
ProtectedDataGuard guard;
std::vector<std::string> ld_library_paths;
std::vector<std::string> default_library_paths;
parse_path(ld_library_path, ":", &ld_library_paths);
parse_path(default_library_path, ":", &default_library_paths);
android_namespace_t* ns = new (g_namespace_allocator.alloc()) android_namespace_t();
ns->set_name(name);
ns->set_isolated(is_isolated);
ns->set_ld_library_paths(std::move(ld_library_paths));
ns->set_default_library_paths(std::move(default_library_paths));
// TODO(dimtiry): Should this be global group of caller's namespace?
auto global_group = make_global_group(&g_default_namespace);
std::copy(global_group.begin(), global_group.end(), std::back_inserter(ns->soinfo_list()));
return ns;
}
static ElfW(Addr) call_ifunc_resolver(ElfW(Addr) resolver_addr) {
typedef ElfW(Addr) (*ifunc_resolver_t)(void);
ifunc_resolver_t ifunc_resolver = reinterpret_cast<ifunc_resolver_t>(resolver_addr);
@ -2694,6 +2969,10 @@ void soinfo::set_dt_flags_1(uint32_t dt_flags_1) {
}
}
void soinfo::set_nodelete() {
rtld_flags_ |= RTLD_NODELETE;
}
const char* soinfo::get_realpath() const {
#if defined(__work_around_b_24465209__)
if (has_min_version(2)) {
@ -2760,13 +3039,21 @@ soinfo::soinfo_list_t& soinfo::get_parents() {
static std::vector<std::string> g_empty_runpath;
const std::vector<std::string>& soinfo::get_dt_runpath() const {
if (has_min_version(2)) {
if (has_min_version(3)) {
return dt_runpath_;
}
return g_empty_runpath;
}
android_namespace_t* soinfo::get_namespace() {
if (has_min_version(3)) {
return namespace_;
}
return &g_default_namespace;
}
ElfW(Addr) soinfo::resolve_symbol_address(const ElfW(Sym)* s) const {
if (ELF_ST_TYPE(s->st_info) == STT_GNU_IFUNC) {
return call_ifunc_resolver(s->st_value + load_bias);
@ -3464,7 +3751,8 @@ static soinfo* linker_soinfo_for_gdb = nullptr;
* be on the soinfo list.
*/
static void init_linker_info_for_gdb(ElfW(Addr) linker_base) {
linker_soinfo_for_gdb = new (linker_soinfo_for_gdb_buf) soinfo(LINKER_PATH, nullptr, 0, 0);
linker_soinfo_for_gdb = new (linker_soinfo_for_gdb_buf) soinfo(nullptr, LINKER_PATH,
nullptr, 0, 0);
linker_soinfo_for_gdb->load_bias = linker_base;
@ -3481,14 +3769,25 @@ static void init_linker_info_for_gdb(ElfW(Addr) linker_base) {
insert_soinfo_into_debug_map(linker_soinfo_for_gdb);
}
static void init_default_ld_library_path() {
static void init_default_namespace() {
g_default_namespace.set_name("(default)");
g_default_namespace.set_isolated(false);
const char *interp = phdr_table_get_interpreter_name(somain->phdr, somain->phnum,
somain->load_bias);
const char* bname = basename(interp);
if (bname && (strcmp(bname, "linker_asan") == 0 || strcmp(bname, "linker_asan64") == 0))
if (bname && (strcmp(bname, "linker_asan") == 0 || strcmp(bname, "linker_asan64") == 0)) {
g_default_ld_paths = kAsanDefaultLdPaths;
else
} else {
g_default_ld_paths = kDefaultLdPaths;
}
std::vector<std::string> ld_default_paths;
for (size_t i = 0; g_default_ld_paths[i] != nullptr; ++i) {
ld_default_paths.push_back(g_default_ld_paths[i]);
}
g_default_namespace.set_default_library_paths(std::move(ld_default_paths));
};
extern "C" int __system_properties_init(void);
@ -3529,7 +3828,7 @@ static ElfW(Addr) __linker_init_post_relocation(KernelArgumentBlock& args, ElfW(
INFO("[ android linker & debugger ]");
soinfo* si = soinfo_alloc(args.argv[0], nullptr, 0, RTLD_GLOBAL);
soinfo* si = soinfo_alloc(&g_default_namespace, args.argv[0], nullptr, 0, RTLD_GLOBAL);
if (si == nullptr) {
exit(EXIT_FAILURE);
}
@ -3581,11 +3880,10 @@ static ElfW(Addr) __linker_init_post_relocation(KernelArgumentBlock& args, ElfW(
somain = si;
init_default_ld_library_path();
init_default_namespace();
if (!si->prelink_image()) {
__libc_format_fd(2, "CANNOT LINK EXECUTABLE: %s\n", linker_get_error_buffer());
exit(EXIT_FAILURE);
__libc_fatal("CANNOT LINK EXECUTABLE: %s", linker_get_error_buffer());
}
// add somain to global group
@ -3613,15 +3911,13 @@ static ElfW(Addr) __linker_init_post_relocation(KernelArgumentBlock& args, ElfW(
needed_library_name_list.copy_to_array(needed_library_names, needed_libraries_count);
if (needed_libraries_count > 0 &&
!find_libraries(si, needed_library_names, needed_libraries_count, nullptr,
&g_ld_preloads, ld_preloads_count, RTLD_GLOBAL, nullptr,
!find_libraries(&g_default_namespace, si, needed_library_names, needed_libraries_count,
nullptr, &g_ld_preloads, ld_preloads_count, RTLD_GLOBAL, nullptr,
/* add_as_children */ true)) {
__libc_format_fd(2, "CANNOT LINK EXECUTABLE: %s\n", linker_get_error_buffer());
exit(EXIT_FAILURE);
__libc_fatal("CANNOT LINK EXECUTABLE: %s", linker_get_error_buffer());
} else if (needed_libraries_count == 0) {
if (!si->link_image(g_empty_list, soinfo::soinfo_list_t::make_list(si), nullptr)) {
__libc_format_fd(2, "CANNOT LINK EXECUTABLE: %s\n", linker_get_error_buffer());
exit(EXIT_FAILURE);
__libc_fatal("CANNOT LINK EXECUTABLE: %s", linker_get_error_buffer());
}
si->increment_ref_count();
}
@ -3730,7 +4026,7 @@ extern "C" ElfW(Addr) __linker_init(void* raw_args) {
ElfW(Ehdr)* elf_hdr = reinterpret_cast<ElfW(Ehdr)*>(linker_addr);
ElfW(Phdr)* phdr = reinterpret_cast<ElfW(Phdr)*>(linker_addr + elf_hdr->e_phoff);
soinfo linker_so(nullptr, nullptr, 0, 0);
soinfo linker_so(nullptr, nullptr, nullptr, 0, 0);
// If the linker is not acting as PT_INTERP entry_point is equal to
// _start. Which means that the linker is running as an executable and
@ -3739,7 +4035,7 @@ extern "C" ElfW(Addr) __linker_init(void* raw_args) {
// This happens when user tries to run 'adb shell /system/bin/linker'
// see also https://code.google.com/p/android/issues/detail?id=63174
if (reinterpret_cast<ElfW(Addr)>(&_start) == entry_point) {
__libc_fatal("This is %s, the helper program for shared library executables.\n", args.argv[0]);
__libc_fatal("This is %s, the helper program for shared library executables.", args.argv[0]);
}
linker_so.base = linker_addr;
@ -3757,15 +4053,7 @@ extern "C" ElfW(Addr) __linker_init(void* raw_args) {
// are not yet initialized, and therefore we cannot use linked_list.push_*
// functions at this point.
if (!(linker_so.prelink_image() && linker_so.link_image(g_empty_list, g_empty_list, nullptr))) {
// It would be nice to print an error message, but if the linker
// can't link itself, there's no guarantee that we'll be able to
// call write() (because it involves a GOT reference). We may as
// well try though...
const char* msg = "CANNOT LINK EXECUTABLE: ";
write(2, msg, strlen(msg));
write(2, __linker_dl_err_buf, strlen(__linker_dl_err_buf));
write(2, "\n", 1);
_exit(EXIT_FAILURE);
__libc_fatal("CANNOT LINK EXECUTABLE: %s", linker_get_error_buffer());
}
__libc_init_main_thread(args);
@ -3781,6 +4069,7 @@ extern "C" ElfW(Addr) __linker_init(void* raw_args) {
// before get_libdl_info().
solist = get_libdl_info();
sonext = get_libdl_info();
g_default_namespace.soinfo_list().push_back(get_libdl_info());
// We have successfully fixed our own relocations. It's safe to run
// the main part of the linker now.

View file

@ -86,7 +86,7 @@
#define SUPPORTED_DT_FLAGS_1 (DF_1_NOW | DF_1_GLOBAL | DF_1_NODELETE)
#define SOINFO_VERSION 2
#define SOINFO_VERSION 3
#if defined(__work_around_b_24465209__)
#define SOINFO_NAME_LEN 128
@ -261,7 +261,8 @@ struct soinfo {
bool has_DT_SYMBOLIC;
public:
soinfo(const char* name, const struct stat* file_stat, off64_t file_offset, int rtld_flags);
soinfo(android_namespace_t* ns, const char* name, const struct stat* file_stat,
off64_t file_offset, int rtld_flags);
void call_constructors();
void call_destructors();
@ -311,6 +312,7 @@ struct soinfo {
void set_linked();
void set_linker_flag();
void set_main_executable();
void set_nodelete();
void increment_ref_count();
size_t decrement_ref_count();
@ -332,6 +334,7 @@ struct soinfo {
void set_dt_runpath(const char *);
const std::vector<std::string>& get_dt_runpath() const;
android_namespace_t* get_namespace();
private:
bool elf_lookup(SymbolName& symbol_name, const version_info* vi, uint32_t* symbol_index) const;
@ -394,7 +397,9 @@ struct soinfo {
uint32_t target_sdk_version_;
// version >= 3
std::vector<std::string> dt_runpath_;
android_namespace_t* namespace_;
friend soinfo* get_libdl_info();
};
@ -422,7 +427,9 @@ void do_dlclose(soinfo* si);
int do_dl_iterate_phdr(int (*cb)(dl_phdr_info* info, size_t size, void* data), void* data);
const ElfW(Sym)* dlsym_linear_lookup(const char* name, soinfo** found, soinfo* caller, void* handle);
const ElfW(Sym)* dlsym_linear_lookup(android_namespace_t* ns, const char* name, soinfo** found,
soinfo* caller, void* handle);
soinfo* find_containing_library(const void* addr);
const ElfW(Sym)* dlsym_handle_lookup(soinfo* si, soinfo** found, const char* name);
@ -437,4 +444,8 @@ size_t linker_get_error_buffer_size();
void set_application_target_sdk_version(uint32_t target);
uint32_t get_application_target_sdk_version();
bool init_public_namespace(const char* path);
android_namespace_t* create_namespace(const char* name, const char* ld_library_path,
const char* default_library_path, bool is_isolated);
#endif

View file

@ -20,7 +20,7 @@
bool normalize_path(const char* path, std::string* normalized_path) {
// Input should be an absolute path
if (path[0] != '/') {
PRINT("canonize_path - invalid input: '%s', the input path should be absolute", path);
PRINT("normalize_path - invalid input: '%s', the input path should be absolute", path);
return false;
}
@ -61,3 +61,47 @@ bool normalize_path(const char* path, std::string* normalized_path) {
return true;
}
bool file_is_in_dir(const std::string& file, const std::string& dir) {
const char* needle = dir.c_str();
const char* haystack = file.c_str();
size_t needle_len = strlen(needle);
return (strncmp(haystack, needle, needle_len) == 0 &&
haystack[needle_len] == '/' &&
strchr(haystack + needle_len + 1, '/') == nullptr);
}
const char* const kZipFileSeparator = "!/";
bool parse_zip_path(const char* input_path, std::string* zip_path, std::string* entry_path) {
std::string normalized_path;
if (!normalize_path(input_path, &normalized_path)) {
return false;
}
const char* const path = normalized_path.c_str();
TRACE("Trying zip file open from path '%s' -> normalized '%s'", input_path, path);
// Treat an '!/' separator inside a path as the separator between the name
// of the zip file on disk and the subdirectory to search within it.
// For example, if path is "foo.zip!/bar/bas/x.so", then we search for
// "bar/bas/x.so" within "foo.zip".
const char* const separator = strstr(path, kZipFileSeparator);
if (separator == nullptr) {
return false;
}
char buf[512];
if (strlcpy(buf, path, sizeof(buf)) >= sizeof(buf)) {
PRINT("Warning: ignoring very long library path: %s", path);
return false;
}
buf[separator - path] = '\0';
*zip_path = buf;
*entry_path = &buf[separator - path + 2];
return true;
}

View file

@ -18,6 +18,10 @@
#include <string>
extern const char* const kZipFileSeparator;
bool normalize_path(const char* path, std::string* normalized_path);
bool file_is_in_dir(const std::string& file, const std::string& dir);
bool parse_zip_path(const char* input_path, std::string* zip_path, std::string* entry_path);
#endif

View file

@ -43,3 +43,29 @@ TEST(linker_utils, normalize_path_smoke) {
ASSERT_FALSE(normalize_path("root///dir/.///dir2/somedir/../zipfile!/dir/dir9//..///afile", &output));
ASSERT_EQ("unchanged", output);
}
TEST(linker_utils, file_is_in_dir_smoke) {
ASSERT_TRUE(file_is_in_dir("/foo/bar/file", "/foo/bar"));
ASSERT_FALSE(file_is_in_dir("/foo/bar/file", "/foo"));
ASSERT_FALSE(file_is_in_dir("/foo/bar/file", "/bar/foo"));
ASSERT_TRUE(file_is_in_dir("/file", ""));
ASSERT_FALSE(file_is_in_dir("/file", "/"));
}
TEST(linker_utils, parse_zip_path_smoke) {
std::string zip_path;
std::string entry_path;
ASSERT_FALSE(parse_zip_path("/not/a/zip/path/file.zip", &zip_path, &entry_path));
ASSERT_FALSE(parse_zip_path("/not/a/zip/path/file.zip!path/in/zip", &zip_path, &entry_path));
ASSERT_TRUE(parse_zip_path("/zip/path/file.zip!/path/in/zip", &zip_path, &entry_path));
ASSERT_EQ("/zip/path/file.zip", zip_path);
ASSERT_EQ("path/in/zip", entry_path);
ASSERT_TRUE(parse_zip_path("/zip/path/file2.zip!/", &zip_path, &entry_path));
ASSERT_EQ("/zip/path/file2.zip", zip_path);
ASSERT_EQ("", entry_path);
}

View file

@ -28,9 +28,17 @@ ifneq ($(findstring LIBRARY, $(build_target)),LIBRARY)
LOCAL_MODULE_STEM_32 := $(module)32
LOCAL_MODULE_STEM_64 := $(module)64
else
ifneq ($($(module)_install_to_out_data_dir),)
$(module)_install_to_out_data := true
endif
ifeq ($($(module)_install_to_out_data),true)
LOCAL_MODULE_PATH_32 := $($(TARGET_2ND_ARCH_VAR_PREFIX)TARGET_OUT_DATA_NATIVE_TESTS)/$(module)
LOCAL_MODULE_PATH_64 := $(TARGET_OUT_DATA_NATIVE_TESTS)/$(module)
ifeq ($($(module)_install_to_out_data_dir),)
$(module)_install_to_out_data_dir := $(module)
endif
LOCAL_MODULE_PATH_32 := $($(TARGET_2ND_ARCH_VAR_PREFIX)TARGET_OUT_DATA_NATIVE_TESTS)/$($(module)_install_to_out_data_dir)
LOCAL_MODULE_PATH_64 := $(TARGET_OUT_DATA_NATIVE_TESTS)/$($(module)_install_to_out_data_dir)
endif
endif

View file

@ -52,14 +52,14 @@ typedef int (*fn)(void);
#define LIBSIZE 1024*1024 // how much address space to reserve for it
#if defined(__LP64__)
#define LIBPATH_PREFIX "/nativetest64/"
#define NATIVE_TESTS_PATH "/nativetest64"
#else
#define LIBPATH_PREFIX "/nativetest/"
#define NATIVE_TESTS_PATH "/nativetest"
#endif
#define LIBPATH LIBPATH_PREFIX "libdlext_test_fd/libdlext_test_fd.so"
#define LIBZIPPATH LIBPATH_PREFIX "libdlext_test_zip/libdlext_test_zip_zipaligned.zip"
#define LIBZIPPATH_WITH_RUNPATH LIBPATH_PREFIX "libdlext_test_runpath_zip/libdlext_test_runpath_zip_zipaligned.zip"
#define LIBPATH NATIVE_TESTS_PATH "/libdlext_test_fd/libdlext_test_fd.so"
#define LIBZIPPATH NATIVE_TESTS_PATH "/libdlext_test_zip/libdlext_test_zip_zipaligned.zip"
#define LIBZIPPATH_WITH_RUNPATH NATIVE_TESTS_PATH "/libdlext_test_runpath_zip/libdlext_test_runpath_zip_zipaligned.zip"
#define LIBZIP_OFFSET PAGE_SIZE
@ -602,3 +602,192 @@ void DlExtRelroSharingTest::SpawnChildrenAndMeasurePss(const char* lib, bool sha
ASSERT_EQ(0, WEXITSTATUS(status));
}
}
// Testing namespaces
static const char* g_public_lib = "libnstest_public.so";
TEST(dlext, ns_smoke) {
static const char* root_lib = "libnstest_root.so";
std::string path = std::string("libc.so:libc++.so:libdl.so:libm.so:") + g_public_lib;
ASSERT_FALSE(android_init_public_namespace(path.c_str()));
ASSERT_STREQ("android_init_public_namespace failed: Error initializing public namespace: "
"\"libnstest_public.so\" was not found in the default namespace", dlerror());
const std::string lib_path = std::string(getenv("ANDROID_DATA")) + NATIVE_TESTS_PATH;
void* handle_public = dlopen((lib_path + "/public_namespace_libs/" + g_public_lib).c_str(), RTLD_NOW);
ASSERT_TRUE(handle_public != nullptr) << dlerror();
ASSERT_TRUE(android_init_public_namespace(path.c_str())) << dlerror();
// Check that libraries added to public namespace are NODELETE
dlclose(handle_public);
handle_public = dlopen((lib_path + "/public_namespace_libs/" + g_public_lib).c_str(), RTLD_NOW | RTLD_NOLOAD);
ASSERT_TRUE(handle_public != nullptr) << dlerror();
android_namespace_t* ns1 = android_create_namespace("private", nullptr, (lib_path + "/private_namespace_libs").c_str(), false);
ASSERT_TRUE(ns1 != nullptr) << dlerror();
android_namespace_t* ns2 = android_create_namespace("private_isolated", nullptr, (lib_path + "/private_namespace_libs").c_str(), true);
ASSERT_TRUE(ns2 != nullptr) << dlerror();
// This should not have affect search path for default namespace:
ASSERT_TRUE(dlopen(root_lib, RTLD_NOW) == nullptr);
void* handle = dlopen(g_public_lib, RTLD_NOW);
ASSERT_TRUE(handle != nullptr) << dlerror();
dlclose(handle);
android_dlextinfo extinfo;
extinfo.flags = ANDROID_DLEXT_USE_NAMESPACE;
extinfo.library_namespace = ns1;
void* handle1 = android_dlopen_ext(root_lib, RTLD_NOW, &extinfo);
ASSERT_TRUE(handle1 != nullptr) << dlerror();
extinfo.library_namespace = ns2;
void* handle2 = android_dlopen_ext(root_lib, RTLD_NOW, &extinfo);
ASSERT_TRUE(handle2 != nullptr) << dlerror();
ASSERT_TRUE(handle1 != handle2);
typedef const char* (*fn_t)();
fn_t ns_get_local_string1 = reinterpret_cast<fn_t>(dlsym(handle1, "ns_get_local_string"));
ASSERT_TRUE(ns_get_local_string1 != nullptr) << dlerror();
fn_t ns_get_local_string2 = reinterpret_cast<fn_t>(dlsym(handle2, "ns_get_local_string"));
ASSERT_TRUE(ns_get_local_string2 != nullptr) << dlerror();
EXPECT_STREQ("This string is local to root library", ns_get_local_string1());
EXPECT_STREQ("This string is local to root library", ns_get_local_string2());
ASSERT_TRUE(ns_get_local_string1() != ns_get_local_string2());
fn_t ns_get_private_extern_string1 =
reinterpret_cast<fn_t>(dlsym(handle1, "ns_get_private_extern_string"));
ASSERT_TRUE(ns_get_private_extern_string1 != nullptr) << dlerror();
fn_t ns_get_private_extern_string2 =
reinterpret_cast<fn_t>(dlsym(handle2, "ns_get_private_extern_string"));
ASSERT_TRUE(ns_get_private_extern_string2 != nullptr) << dlerror();
EXPECT_STREQ("This string is from private namespace", ns_get_private_extern_string1());
EXPECT_STREQ("This string is from private namespace", ns_get_private_extern_string2());
ASSERT_TRUE(ns_get_private_extern_string1() != ns_get_private_extern_string2());
fn_t ns_get_public_extern_string1 =
reinterpret_cast<fn_t>(dlsym(handle1, "ns_get_public_extern_string"));
ASSERT_TRUE(ns_get_public_extern_string1 != nullptr) << dlerror();
fn_t ns_get_public_extern_string2 =
reinterpret_cast<fn_t>(dlsym(handle2, "ns_get_public_extern_string"));
ASSERT_TRUE(ns_get_public_extern_string2 != nullptr) << dlerror();
EXPECT_STREQ("This string is from public namespace", ns_get_public_extern_string1());
ASSERT_TRUE(ns_get_public_extern_string1() == ns_get_public_extern_string2());
// and now check that dlopen() does the right thing in terms of preserving namespace
fn_t ns_get_dlopened_string1 = reinterpret_cast<fn_t>(dlsym(handle1, "ns_get_dlopened_string"));
ASSERT_TRUE(ns_get_dlopened_string1 != nullptr) << dlerror();
fn_t ns_get_dlopened_string2 = reinterpret_cast<fn_t>(dlsym(handle2, "ns_get_dlopened_string"));
ASSERT_TRUE(ns_get_dlopened_string2 != nullptr) << dlerror();
EXPECT_STREQ("This string is from private namespace (dlopened library)", ns_get_dlopened_string1());
EXPECT_STREQ("This string is from private namespace (dlopened library)", ns_get_dlopened_string2());
ASSERT_TRUE(ns_get_dlopened_string1() != ns_get_dlopened_string2());
dlclose(handle1);
// Check if handle2 is still alive (and well)
ASSERT_STREQ("This string is local to root library", ns_get_local_string2());
ASSERT_STREQ("This string is from private namespace", ns_get_private_extern_string2());
ASSERT_STREQ("This string is from public namespace", ns_get_public_extern_string2());
ASSERT_STREQ("This string is from private namespace (dlopened library)", ns_get_dlopened_string2());
dlclose(handle2);
}
TEST(dlext, ns_isolated) {
static const char* root_lib = "libnstest_root_not_isolated.so";
std::string path = std::string("libc.so:libc++.so:libdl.so:libm.so:") + g_public_lib;
const std::string lib_path = std::string(getenv("ANDROID_DATA")) + NATIVE_TESTS_PATH;
void* handle_public = dlopen((lib_path + "/public_namespace_libs/" + g_public_lib).c_str(), RTLD_NOW);
ASSERT_TRUE(handle_public != nullptr) << dlerror();
ASSERT_TRUE(android_init_public_namespace(path.c_str())) << dlerror();
android_namespace_t* ns_not_isolated = android_create_namespace("private", nullptr, (lib_path + "/private_namespace_libs").c_str(), false);
ASSERT_TRUE(ns_not_isolated != nullptr) << dlerror();
android_namespace_t* ns_isolated = android_create_namespace("private_isolated1", nullptr, (lib_path + "/private_namespace_libs").c_str(), true);
ASSERT_TRUE(ns_isolated != nullptr) << dlerror();
android_namespace_t* ns_isolated2 = android_create_namespace("private_isolated2", (lib_path + "/private_namespace_libs").c_str(), nullptr, true);
ASSERT_TRUE(ns_isolated2 != nullptr) << dlerror();
ASSERT_TRUE(dlopen(root_lib, RTLD_NOW) == nullptr);
ASSERT_STREQ("dlopen failed: library \"libnstest_root_not_isolated.so\" not found", dlerror());
std::string lib_private_external_path =
lib_path + "/private_namespace_libs_external/libnstest_private_external.so";
// Load lib_private_external_path to default namespace
// (it should remain invisible for the isolated namespaces after this)
void* handle = dlopen(lib_private_external_path.c_str(), RTLD_NOW);
ASSERT_TRUE(handle != nullptr) << dlerror();
android_dlextinfo extinfo;
extinfo.flags = ANDROID_DLEXT_USE_NAMESPACE;
extinfo.library_namespace = ns_not_isolated;
void* handle1 = android_dlopen_ext(root_lib, RTLD_NOW, &extinfo);
ASSERT_TRUE(handle1 != nullptr) << dlerror();
extinfo.library_namespace = ns_isolated;
void* handle2 = android_dlopen_ext(root_lib, RTLD_NOW, &extinfo);
ASSERT_TRUE(handle2 == nullptr);
ASSERT_STREQ("dlopen failed: library \"libnstest_private_external.so\" not found", dlerror());
// Check dlopen by absolute path
handle2 = android_dlopen_ext(lib_private_external_path.c_str(), RTLD_NOW, &extinfo);
ASSERT_TRUE(handle2 == nullptr);
ASSERT_EQ("dlopen failed: library \"" + lib_private_external_path + "\" not found", dlerror());
extinfo.library_namespace = ns_isolated2;
handle2 = android_dlopen_ext(root_lib, RTLD_NOW, &extinfo);
ASSERT_TRUE(handle2 == nullptr);
ASSERT_STREQ("dlopen failed: library \"libnstest_private_external.so\" not found", dlerror());
// Check dlopen by absolute path
handle2 = android_dlopen_ext(lib_private_external_path.c_str(), RTLD_NOW, &extinfo);
ASSERT_TRUE(handle2 == nullptr);
ASSERT_EQ("dlopen failed: library \"" + lib_private_external_path + "\" not found", dlerror());
typedef const char* (*fn_t)();
fn_t ns_get_local_string = reinterpret_cast<fn_t>(dlsym(handle1, "ns_get_local_string"));
ASSERT_TRUE(ns_get_local_string != nullptr) << dlerror();
ASSERT_STREQ("This string is local to root library", ns_get_local_string());
fn_t ns_get_private_extern_string =
reinterpret_cast<fn_t>(dlsym(handle1, "ns_get_private_extern_string"));
ASSERT_TRUE(ns_get_private_extern_string != nullptr) << dlerror();
ASSERT_STREQ("This string is from private namespace", ns_get_private_extern_string());
fn_t ns_get_public_extern_string =
reinterpret_cast<fn_t>(dlsym(handle1, "ns_get_public_extern_string"));
ASSERT_TRUE(ns_get_public_extern_string != nullptr) << dlerror();
ASSERT_STREQ("This string is from public namespace", ns_get_public_extern_string());
fn_t ns_get_dlopened_string = reinterpret_cast<fn_t>(dlsym(handle1, "ns_get_dlopened_string"));
ASSERT_TRUE(ns_get_dlopened_string != nullptr) << dlerror();
ASSERT_STREQ("This string is from private namespace (dlopened library)", ns_get_dlopened_string());
dlclose(handle1);
}

View file

@ -0,0 +1,84 @@
#
# Copyright (C) 2015 The Android Open Source Project
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
#
# -----------------------------------------------------------------------------
# This set of libraries are used to verify linker namespaces.
# -----------------------------------------------------------------------------
# -----------------------------------------------------------------------------
# Test cases
# 1. Check that private libraries loaded in different namespaces are
# different. Check that dlsym does not confuse them.
# 2. Check that public libraries loaded in different namespaces are shared
# between them.
# 3. Check that namespace sticks on dlopen
#
# Dependency tree (visibility)
# libnstest_root.so (this should be local to the namespace)
# +-> libnstest_public.so
# +-> libnstest_private.so
#
# libnstest_dlopened.so (library in private namespace dlopened from libnstest_root.so)
# -----------------------------------------------------------------------------
libnstest_root_src_files := namespaces_root.cpp
libnstest_root_shared_libraries := libnstest_public libnstest_private
libnstest_root_install_to_out_data_dir := private_namespace_libs
module := libnstest_root
include $(LOCAL_PATH)/Android.build.target.testlib.mk
libnstest_public_src_files := namespaces_public.cpp
module := libnstest_public
libnstest_public_install_to_out_data_dir := public_namespace_libs
include $(LOCAL_PATH)/Android.build.target.testlib.mk
libnstest_private_src_files := namespaces_private.cpp
libnstest_private_install_to_out_data_dir := private_namespace_libs
module := libnstest_private
include $(LOCAL_PATH)/Android.build.target.testlib.mk
libnstest_dlopened_src_files := namespaces_dlopened.cpp
libnstest_dlopened_install_to_out_data_dir := private_namespace_libs
module := libnstest_dlopened
include $(LOCAL_PATH)/Android.build.target.testlib.mk
# -----------------------------------------------------------------------------
# This set of libraries is to test isolated namespaces
#
# Isolated namespaces do not allow loading of the library outside of
# the search paths.
#
# This library cannot be loaded in isolated namespace because one of DT_NEEDED
# libraries is outside of the search paths.
#
# libnstest_root_not_isolated.so (DT_RUNPATH = $ORIGIN/../private_namespace_libs_external/)
# +-> libnstest_public.so
# +-> libnstest_private_external.so (located in $ORIGIN/../private_namespace_libs_external/)
#
# Search path: $NATIVE_TESTS/private_namespace_libs/
# -----------------------------------------------------------------------------
libnstest_root_not_isolated_src_files := namespaces_root.cpp
libnstest_root_not_isolated_shared_libraries := libnstest_public libnstest_private_external
libnstest_root_not_isolated_install_to_out_data_dir := private_namespace_libs
libnstest_root_not_isolated_ldflags := -Wl,--rpath,\$$ORIGIN/../private_namespace_libs_external \
-Wl,--enable-new-dtags
module := libnstest_root_not_isolated
include $(LOCAL_PATH)/Android.build.target.testlib.mk
libnstest_private_external_src_files := namespaces_private.cpp
libnstest_private_external_install_to_out_data_dir := private_namespace_libs_external
module := libnstest_private_external
include $(LOCAL_PATH)/Android.build.target.testlib.mk

View file

@ -0,0 +1,20 @@
#
# Copyright (C) 2015 The Android Open Source Project
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
#
build_target := SHARED_LIBRARY
build_type := target
include $(TEST_PATH)/Android.build.mk

View file

@ -26,6 +26,7 @@ common_additional_dependencies := \
$(LOCAL_PATH)/Android.build.dlopen_check_order_dlsym.mk \
$(LOCAL_PATH)/Android.build.dlopen_check_order_reloc_siblings.mk \
$(LOCAL_PATH)/Android.build.dlopen_check_order_reloc_main_executable.mk \
$(LOCAL_PATH)/Android.build.linker_namespaces.mk \
$(LOCAL_PATH)/Android.build.pthread_atfork.mk \
$(LOCAL_PATH)/Android.build.testlib.mk \
$(LOCAL_PATH)/Android.build.versioned_lib.mk \
@ -212,6 +213,11 @@ libtest_nodelete_dt_flags_1_ldflags := -Wl,-z,nodelete
module := libtest_nodelete_dt_flags_1
include $(LOCAL_PATH)/Android.build.testlib.mk
# -----------------------------------------------------------------------------
# Build test helper libraries for linker namespaces
# -----------------------------------------------------------------------------
include $(LOCAL_PATH)/Android.build.linker_namespaces.mk
# -----------------------------------------------------------------------------
# Build DT_RUNPATH test helper libraries
# -----------------------------------------------------------------------------

View file

@ -0,0 +1,19 @@
/*
* Copyright (C) 2015 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
const char* g_private_dlopened_string = "This string is from private namespace "
"(dlopened library)";

View file

@ -0,0 +1,18 @@
/*
* Copyright (C) 2015 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
const char* g_private_extern_string = "This string is from private namespace";

View file

@ -0,0 +1,18 @@
/*
* Copyright (C) 2015 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
const char* g_public_extern_string = "This string is from public namespace";

View file

@ -0,0 +1,49 @@
/*
* Copyright (C) 2015 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include <dlfcn.h>
static const char* g_local_string = "This string is local to root library";
extern "C" const char* g_private_extern_string;
extern "C" const char* g_public_extern_string;
bool g_dlopened = false;
extern "C" const char* ns_get_local_string() {
return g_local_string;
}
extern "C" const char* ns_get_private_extern_string() {
return g_private_extern_string;
}
extern "C" const char* ns_get_public_extern_string() {
return g_public_extern_string;
}
extern "C" const char* ns_get_dlopened_string() {
void* handle = dlopen("libnstest_dlopened.so", RTLD_NOW | RTLD_GLOBAL);
if (handle == nullptr) {
return nullptr;
}
const char* result = *static_cast<const char**>(dlsym(handle, "g_private_dlopened_string"));
if (result != nullptr) {
g_dlopened = true;
}
return result;
}