1/*
2 * Copyright (C) 2015 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17#include "nativeloader/native_loader.h"
18#include <nativehelper/ScopedUtfChars.h>
19
20#include <dlfcn.h>
21#ifdef __ANDROID__
22#define LOG_TAG "libnativeloader"
23#include "nativeloader/dlext_namespaces.h"
24#include "cutils/properties.h"
25#include "log/log.h"
26#endif
27#include <dirent.h>
28#include <sys/types.h>
29#include "nativebridge/native_bridge.h"
30
31#include <algorithm>
32#include <memory>
33#include <mutex>
34#include <string>
35#include <vector>
36
37#include <android-base/file.h>
38#include <android-base/macros.h>
39#include <android-base/strings.h>
40
41#ifdef __BIONIC__
42#include <android-base/properties.h>
43#endif
44
45#define CHECK(predicate) LOG_ALWAYS_FATAL_IF(!(predicate),\
46                                             "%s:%d: %s CHECK '" #predicate "' failed.",\
47                                             __FILE__, __LINE__, __FUNCTION__)
48
49using namespace std::string_literals;
50
51namespace android {
52
53#if defined(__ANDROID__)
54class NativeLoaderNamespace {
55 public:
56  NativeLoaderNamespace()
57      : android_ns_(nullptr), native_bridge_ns_(nullptr) { }
58
59  explicit NativeLoaderNamespace(android_namespace_t* ns)
60      : android_ns_(ns), native_bridge_ns_(nullptr) { }
61
62  explicit NativeLoaderNamespace(native_bridge_namespace_t* ns)
63      : android_ns_(nullptr), native_bridge_ns_(ns) { }
64
65  NativeLoaderNamespace(NativeLoaderNamespace&& that) = default;
66  NativeLoaderNamespace(const NativeLoaderNamespace& that) = default;
67
68  NativeLoaderNamespace& operator=(const NativeLoaderNamespace& that) = default;
69
70  android_namespace_t* get_android_ns() const {
71    CHECK(native_bridge_ns_ == nullptr);
72    return android_ns_;
73  }
74
75  native_bridge_namespace_t* get_native_bridge_ns() const {
76    CHECK(android_ns_ == nullptr);
77    return native_bridge_ns_;
78  }
79
80  bool is_android_namespace() const {
81    return native_bridge_ns_ == nullptr;
82  }
83
84 private:
85  // Only one of them can be not null
86  android_namespace_t* android_ns_;
87  native_bridge_namespace_t* native_bridge_ns_;
88};
89
90static constexpr const char kPublicNativeLibrariesSystemConfigPathFromRoot[] =
91    "/etc/public.libraries.txt";
92static constexpr const char kPublicNativeLibrariesExtensionConfigPrefix[] = "public.libraries-";
93static constexpr const size_t kPublicNativeLibrariesExtensionConfigPrefixLen =
94    sizeof(kPublicNativeLibrariesExtensionConfigPrefix) - 1;
95static constexpr const char kPublicNativeLibrariesExtensionConfigSuffix[] = ".txt";
96static constexpr const size_t kPublicNativeLibrariesExtensionConfigSuffixLen =
97    sizeof(kPublicNativeLibrariesExtensionConfigSuffix) - 1;
98static constexpr const char kPublicNativeLibrariesVendorConfig[] =
99    "/vendor/etc/public.libraries.txt";
100static constexpr const char kLlndkNativeLibrariesSystemConfigPathFromRoot[] =
101    "/etc/llndk.libraries.txt";
102static constexpr const char kVndkspNativeLibrariesSystemConfigPathFromRoot[] =
103    "/etc/vndksp.libraries.txt";
104
105// The device may be configured to have the vendor libraries loaded to a separate namespace.
106// For historical reasons this namespace was named sphal but effectively it is intended
107// to use to load vendor libraries to separate namespace with controlled interface between
108// vendor and system namespaces.
109static constexpr const char* kVendorNamespaceName = "sphal";
110
111static constexpr const char* kVndkNamespaceName = "vndk";
112
113static constexpr const char* kClassloaderNamespaceName = "classloader-namespace";
114static constexpr const char* kVendorClassloaderNamespaceName = "vendor-classloader-namespace";
115
116// (http://b/27588281) This is a workaround for apps using custom classloaders and calling
117// System.load() with an absolute path which is outside of the classloader library search path.
118// This list includes all directories app is allowed to access this way.
119static constexpr const char* kWhitelistedDirectories = "/data:/mnt/expand";
120
121static bool is_debuggable() {
122  char debuggable[PROP_VALUE_MAX];
123  property_get("ro.debuggable", debuggable, "0");
124  return std::string(debuggable) == "1";
125}
126
127static std::string vndk_version_str() {
128#ifdef __BIONIC__
129  std::string version = android::base::GetProperty("ro.vndk.version", "");
130  if (version != "" && version != "current") {
131    return "." + version;
132  }
133#endif
134  return "";
135}
136
137static void insert_vndk_version_str(std::string* file_name) {
138  CHECK(file_name != nullptr);
139  size_t insert_pos = file_name->find_last_of(".");
140  if (insert_pos == std::string::npos) {
141    insert_pos = file_name->length();
142  }
143  file_name->insert(insert_pos, vndk_version_str());
144}
145
146static const std::function<bool(const std::string&, std::string*)> always_true =
147    [](const std::string&, std::string*) { return true; };
148
149class LibraryNamespaces {
150 public:
151  LibraryNamespaces() : initialized_(false) { }
152
153  bool Create(JNIEnv* env,
154              uint32_t target_sdk_version,
155              jobject class_loader,
156              bool is_shared,
157              bool is_for_vendor,
158              jstring java_library_path,
159              jstring java_permitted_path,
160              NativeLoaderNamespace* ns,
161              std::string* error_msg) {
162    std::string library_path; // empty string by default.
163
164    if (java_library_path != nullptr) {
165      ScopedUtfChars library_path_utf_chars(env, java_library_path);
166      library_path = library_path_utf_chars.c_str();
167    }
168
169    // (http://b/27588281) This is a workaround for apps using custom
170    // classloaders and calling System.load() with an absolute path which
171    // is outside of the classloader library search path.
172    //
173    // This part effectively allows such a classloader to access anything
174    // under /data and /mnt/expand
175    std::string permitted_path = kWhitelistedDirectories;
176
177    if (java_permitted_path != nullptr) {
178      ScopedUtfChars path(env, java_permitted_path);
179      if (path.c_str() != nullptr && path.size() > 0) {
180        permitted_path = permitted_path + ":" + path.c_str();
181      }
182    }
183
184    if (!initialized_ && !InitPublicNamespace(library_path.c_str(), error_msg)) {
185      return false;
186    }
187
188    bool found = FindNamespaceByClassLoader(env, class_loader, nullptr);
189
190    LOG_ALWAYS_FATAL_IF(found,
191                        "There is already a namespace associated with this classloader");
192
193    uint64_t namespace_type = ANDROID_NAMESPACE_TYPE_ISOLATED;
194    if (is_shared) {
195      namespace_type |= ANDROID_NAMESPACE_TYPE_SHARED;
196    }
197
198    if (target_sdk_version < 24) {
199      namespace_type |= ANDROID_NAMESPACE_TYPE_GREYLIST_ENABLED;
200    }
201
202    NativeLoaderNamespace parent_ns;
203    bool found_parent_namespace = FindParentNamespaceByClassLoader(env, class_loader, &parent_ns);
204
205    bool is_native_bridge = false;
206
207    if (found_parent_namespace) {
208      is_native_bridge = !parent_ns.is_android_namespace();
209    } else if (!library_path.empty()) {
210      is_native_bridge = NativeBridgeIsPathSupported(library_path.c_str());
211    }
212
213    std::string system_exposed_libraries = system_public_libraries_;
214    const char* namespace_name = kClassloaderNamespaceName;
215    android_namespace_t* vndk_ns = nullptr;
216    if (is_for_vendor && !is_shared) {
217      LOG_FATAL_IF(is_native_bridge, "Unbundled vendor apk must not use translated architecture");
218
219      // For vendor apks, give access to the vendor lib even though
220      // they are treated as unbundled; the libs and apks are still bundled
221      // together in the vendor partition.
222#if defined(__LP64__)
223      std::string vendor_lib_path = "/vendor/lib64";
224#else
225      std::string vendor_lib_path = "/vendor/lib";
226#endif
227      library_path = library_path + ":" + vendor_lib_path.c_str();
228      permitted_path = permitted_path + ":" + vendor_lib_path.c_str();
229
230      // Also give access to LLNDK libraries since they are available to vendors
231      system_exposed_libraries = system_exposed_libraries + ":" + system_llndk_libraries_.c_str();
232
233      // Give access to VNDK-SP libraries from the 'vndk' namespace.
234      vndk_ns = android_get_exported_namespace(kVndkNamespaceName);
235      LOG_ALWAYS_FATAL_IF(vndk_ns == nullptr,
236                          "Cannot find \"%s\" namespace for vendor apks", kVndkNamespaceName);
237
238      // Different name is useful for debugging
239      namespace_name = kVendorClassloaderNamespaceName;
240      ALOGD("classloader namespace configured for unbundled vendor apk. library_path=%s", library_path.c_str());
241    } else {
242      // oem and product public libraries are NOT available to vendor apks, otherwise it
243      // would be system->vendor violation.
244      if (!oem_public_libraries_.empty()) {
245        system_exposed_libraries = system_exposed_libraries + ':' + oem_public_libraries_;
246      }
247      if (!product_public_libraries_.empty()) {
248        system_exposed_libraries = system_exposed_libraries + ':' + product_public_libraries_;
249      }
250    }
251
252    NativeLoaderNamespace native_loader_ns;
253    if (!is_native_bridge) {
254      android_namespace_t* ns = android_create_namespace(namespace_name,
255                                                         nullptr,
256                                                         library_path.c_str(),
257                                                         namespace_type,
258                                                         permitted_path.c_str(),
259                                                         parent_ns.get_android_ns());
260      if (ns == nullptr) {
261        *error_msg = dlerror();
262        return false;
263      }
264
265      // Note that when vendor_ns is not configured this function will return nullptr
266      // and it will result in linking vendor_public_libraries_ to the default namespace
267      // which is expected behavior in this case.
268      android_namespace_t* vendor_ns = android_get_exported_namespace(kVendorNamespaceName);
269
270      if (!android_link_namespaces(ns, nullptr, system_exposed_libraries.c_str())) {
271        *error_msg = dlerror();
272        return false;
273      }
274
275      if (vndk_ns != nullptr && !system_vndksp_libraries_.empty()) {
276        // vendor apks are allowed to use VNDK-SP libraries.
277        if (!android_link_namespaces(ns, vndk_ns, system_vndksp_libraries_.c_str())) {
278          *error_msg = dlerror();
279          return false;
280        }
281      }
282
283      if (!vendor_public_libraries_.empty()) {
284        if (!android_link_namespaces(ns, vendor_ns, vendor_public_libraries_.c_str())) {
285          *error_msg = dlerror();
286          return false;
287        }
288      }
289
290      native_loader_ns = NativeLoaderNamespace(ns);
291    } else {
292      native_bridge_namespace_t* ns = NativeBridgeCreateNamespace(namespace_name,
293                                                                  nullptr,
294                                                                  library_path.c_str(),
295                                                                  namespace_type,
296                                                                  permitted_path.c_str(),
297                                                                  parent_ns.get_native_bridge_ns());
298
299      if (ns == nullptr) {
300        *error_msg = NativeBridgeGetError();
301        return false;
302      }
303
304      native_bridge_namespace_t* vendor_ns = NativeBridgeGetVendorNamespace();
305
306      if (!NativeBridgeLinkNamespaces(ns, nullptr, system_exposed_libraries.c_str())) {
307        *error_msg = NativeBridgeGetError();
308        return false;
309      }
310
311      if (!vendor_public_libraries_.empty()) {
312        if (!NativeBridgeLinkNamespaces(ns, vendor_ns, vendor_public_libraries_.c_str())) {
313          *error_msg = NativeBridgeGetError();
314          return false;
315        }
316      }
317
318      native_loader_ns = NativeLoaderNamespace(ns);
319    }
320
321    namespaces_.push_back(std::make_pair(env->NewWeakGlobalRef(class_loader), native_loader_ns));
322
323    *ns = native_loader_ns;
324    return true;
325  }
326
327  bool FindNamespaceByClassLoader(JNIEnv* env, jobject class_loader, NativeLoaderNamespace* ns) {
328    auto it = std::find_if(namespaces_.begin(), namespaces_.end(),
329                [&](const std::pair<jweak, NativeLoaderNamespace>& value) {
330                  return env->IsSameObject(value.first, class_loader);
331                });
332    if (it != namespaces_.end()) {
333      if (ns != nullptr) {
334        *ns = it->second;
335      }
336
337      return true;
338    }
339
340    return false;
341  }
342
343  void Initialize() {
344    // Once public namespace is initialized there is no
345    // point in running this code - it will have no effect
346    // on the current list of public libraries.
347    if (initialized_) {
348      return;
349    }
350
351    std::vector<std::string> sonames;
352    const char* android_root_env = getenv("ANDROID_ROOT");
353    std::string root_dir = android_root_env != nullptr ? android_root_env : "/system";
354    std::string public_native_libraries_system_config =
355            root_dir + kPublicNativeLibrariesSystemConfigPathFromRoot;
356    std::string llndk_native_libraries_system_config =
357            root_dir + kLlndkNativeLibrariesSystemConfigPathFromRoot;
358    std::string vndksp_native_libraries_system_config =
359            root_dir + kVndkspNativeLibrariesSystemConfigPathFromRoot;
360
361    std::string product_public_native_libraries_dir = "/product/etc";
362
363    std::string error_msg;
364    LOG_ALWAYS_FATAL_IF(
365        !ReadConfig(public_native_libraries_system_config, &sonames, always_true, &error_msg),
366        "Error reading public native library list from \"%s\": %s",
367        public_native_libraries_system_config.c_str(), error_msg.c_str());
368
369    // For debuggable platform builds use ANDROID_ADDITIONAL_PUBLIC_LIBRARIES environment
370    // variable to add libraries to the list. This is intended for platform tests only.
371    if (is_debuggable()) {
372      const char* additional_libs = getenv("ANDROID_ADDITIONAL_PUBLIC_LIBRARIES");
373      if (additional_libs != nullptr && additional_libs[0] != '\0') {
374        std::vector<std::string> additional_libs_vector = base::Split(additional_libs, ":");
375        std::copy(additional_libs_vector.begin(), additional_libs_vector.end(),
376                  std::back_inserter(sonames));
377      }
378    }
379
380    // android_init_namespaces() expects all the public libraries
381    // to be loaded so that they can be found by soname alone.
382    //
383    // TODO(dimitry): this is a bit misleading since we do not know
384    // if the vendor public library is going to be opened from /vendor/lib
385    // we might as well end up loading them from /system/lib or /product/lib
386    // For now we rely on CTS test to catch things like this but
387    // it should probably be addressed in the future.
388    for (const auto& soname : sonames) {
389      LOG_ALWAYS_FATAL_IF(dlopen(soname.c_str(), RTLD_NOW | RTLD_NODELETE) == nullptr,
390                          "Error preloading public library %s: %s", soname.c_str(), dlerror());
391    }
392
393    system_public_libraries_ = base::Join(sonames, ':');
394
395    // read /system/etc/public.libraries-<companyname>.txt which contain partner defined
396    // system libs that are exposed to apps. The libs in the txt files must be
397    // named as lib<name>.<companyname>.so.
398    sonames.clear();
399    ReadExtensionLibraries(base::Dirname(public_native_libraries_system_config).c_str(), &sonames);
400    oem_public_libraries_ = base::Join(sonames, ':');
401
402    // read /product/etc/public.libraries-<companyname>.txt which contain partner defined
403    // product libs that are exposed to apps.
404    sonames.clear();
405    ReadExtensionLibraries(product_public_native_libraries_dir.c_str(), &sonames);
406    product_public_libraries_ = base::Join(sonames, ':');
407
408    // Insert VNDK version to llndk and vndksp config file names.
409    insert_vndk_version_str(&llndk_native_libraries_system_config);
410    insert_vndk_version_str(&vndksp_native_libraries_system_config);
411
412    sonames.clear();
413    ReadConfig(llndk_native_libraries_system_config, &sonames, always_true);
414    system_llndk_libraries_ = base::Join(sonames, ':');
415
416    sonames.clear();
417    ReadConfig(vndksp_native_libraries_system_config, &sonames, always_true);
418    system_vndksp_libraries_ = base::Join(sonames, ':');
419
420    sonames.clear();
421    // This file is optional, quietly ignore if the file does not exist.
422    ReadConfig(kPublicNativeLibrariesVendorConfig, &sonames, always_true, nullptr);
423
424    vendor_public_libraries_ = base::Join(sonames, ':');
425  }
426
427  void Reset() { namespaces_.clear(); }
428
429 private:
430  void ReadExtensionLibraries(const char* dirname, std::vector<std::string>* sonames) {
431    std::unique_ptr<DIR, decltype(&closedir)> dir(opendir(dirname), closedir);
432    if (dir != nullptr) {
433      // Failing to opening the dir is not an error, which can happen in
434      // webview_zygote.
435      while (struct dirent* ent = readdir(dir.get())) {
436        if (ent->d_type != DT_REG && ent->d_type != DT_LNK) {
437          continue;
438        }
439        const std::string filename(ent->d_name);
440        if (android::base::StartsWith(filename, kPublicNativeLibrariesExtensionConfigPrefix) &&
441            android::base::EndsWith(filename, kPublicNativeLibrariesExtensionConfigSuffix)) {
442          const size_t start = kPublicNativeLibrariesExtensionConfigPrefixLen;
443          const size_t end = filename.size() - kPublicNativeLibrariesExtensionConfigSuffixLen;
444          const std::string company_name = filename.substr(start, end - start);
445          const std::string config_file_path = dirname + "/"s + filename;
446          LOG_ALWAYS_FATAL_IF(
447              company_name.empty(),
448              "Error extracting company name from public native library list file path \"%s\"",
449              config_file_path.c_str());
450
451          std::string error_msg;
452
453          LOG_ALWAYS_FATAL_IF(
454              !ReadConfig(
455                  config_file_path, sonames,
456                  [&company_name](const std::string& soname, std::string* error_msg) {
457                    if (android::base::StartsWith(soname, "lib") &&
458                        android::base::EndsWith(soname, "." + company_name + ".so")) {
459                      return true;
460                    } else {
461                      *error_msg = "Library name \"" + soname +
462                                   "\" does not end with the company name: " + company_name + ".";
463                      return false;
464                    }
465                  },
466                  &error_msg),
467              "Error reading public native library list from \"%s\": %s", config_file_path.c_str(),
468              error_msg.c_str());
469        }
470      }
471    }
472  }
473
474
475  bool ReadConfig(const std::string& configFile, std::vector<std::string>* sonames,
476                  const std::function<bool(const std::string& /* soname */,
477                                           std::string* /* error_msg */)>& check_soname,
478                  std::string* error_msg = nullptr) {
479    // Read list of public native libraries from the config file.
480    std::string file_content;
481    if(!base::ReadFileToString(configFile, &file_content)) {
482      if (error_msg) *error_msg = strerror(errno);
483      return false;
484    }
485
486    std::vector<std::string> lines = base::Split(file_content, "\n");
487
488    for (auto& line : lines) {
489      auto trimmed_line = base::Trim(line);
490      if (trimmed_line[0] == '#' || trimmed_line.empty()) {
491        continue;
492      }
493      size_t space_pos = trimmed_line.rfind(' ');
494      if (space_pos != std::string::npos) {
495        std::string type = trimmed_line.substr(space_pos + 1);
496        if (type != "32" && type != "64") {
497          if (error_msg) *error_msg = "Malformed line: " + line;
498          return false;
499        }
500#if defined(__LP64__)
501        // Skip 32 bit public library.
502        if (type == "32") {
503          continue;
504        }
505#else
506        // Skip 64 bit public library.
507        if (type == "64") {
508          continue;
509        }
510#endif
511        trimmed_line.resize(space_pos);
512      }
513
514      if (check_soname(trimmed_line, error_msg)) {
515        sonames->push_back(trimmed_line);
516      } else {
517        return false;
518      }
519    }
520
521    return true;
522  }
523
524  bool InitPublicNamespace(const char* library_path, std::string* error_msg) {
525    // Ask native bride if this apps library path should be handled by it
526    bool is_native_bridge = NativeBridgeIsPathSupported(library_path);
527
528    // (http://b/25844435) - Some apps call dlopen from generated code (mono jited
529    // code is one example) unknown to linker in which  case linker uses anonymous
530    // namespace. The second argument specifies the search path for the anonymous
531    // namespace which is the library_path of the classloader.
532    initialized_ = android_init_anonymous_namespace(system_public_libraries_.c_str(),
533                                                    is_native_bridge ? nullptr : library_path);
534    if (!initialized_) {
535      *error_msg = dlerror();
536      return false;
537    }
538
539    // and now initialize native bridge namespaces if necessary.
540    if (NativeBridgeInitialized()) {
541      initialized_ = NativeBridgeInitAnonymousNamespace(system_public_libraries_.c_str(),
542                                                        is_native_bridge ? library_path : nullptr);
543      if (!initialized_) {
544        *error_msg = NativeBridgeGetError();
545      }
546    }
547
548    return initialized_;
549  }
550
551  jobject GetParentClassLoader(JNIEnv* env, jobject class_loader) {
552    jclass class_loader_class = env->FindClass("java/lang/ClassLoader");
553    jmethodID get_parent = env->GetMethodID(class_loader_class,
554                                            "getParent",
555                                            "()Ljava/lang/ClassLoader;");
556
557    return env->CallObjectMethod(class_loader, get_parent);
558  }
559
560  bool FindParentNamespaceByClassLoader(JNIEnv* env,
561                                        jobject class_loader,
562                                        NativeLoaderNamespace* ns) {
563    jobject parent_class_loader = GetParentClassLoader(env, class_loader);
564
565    while (parent_class_loader != nullptr) {
566      if (FindNamespaceByClassLoader(env, parent_class_loader, ns)) {
567        return true;
568      }
569
570      parent_class_loader = GetParentClassLoader(env, parent_class_loader);
571    }
572
573    return false;
574  }
575
576  bool initialized_;
577  std::vector<std::pair<jweak, NativeLoaderNamespace>> namespaces_;
578  std::string system_public_libraries_;
579  std::string vendor_public_libraries_;
580  std::string oem_public_libraries_;
581  std::string product_public_libraries_;
582  std::string system_llndk_libraries_;
583  std::string system_vndksp_libraries_;
584
585  DISALLOW_COPY_AND_ASSIGN(LibraryNamespaces);
586};
587
588static std::mutex g_namespaces_mutex;
589static LibraryNamespaces* g_namespaces = new LibraryNamespaces;
590#endif
591
592void InitializeNativeLoader() {
593#if defined(__ANDROID__)
594  std::lock_guard<std::mutex> guard(g_namespaces_mutex);
595  g_namespaces->Initialize();
596#endif
597}
598
599void ResetNativeLoader() {
600#if defined(__ANDROID__)
601  std::lock_guard<std::mutex> guard(g_namespaces_mutex);
602  g_namespaces->Reset();
603#endif
604}
605
606jstring CreateClassLoaderNamespace(JNIEnv* env,
607                                   int32_t target_sdk_version,
608                                   jobject class_loader,
609                                   bool is_shared,
610                                   bool is_for_vendor,
611                                   jstring library_path,
612                                   jstring permitted_path) {
613#if defined(__ANDROID__)
614  std::lock_guard<std::mutex> guard(g_namespaces_mutex);
615
616  std::string error_msg;
617  NativeLoaderNamespace ns;
618  bool success = g_namespaces->Create(env,
619                                      target_sdk_version,
620                                      class_loader,
621                                      is_shared,
622                                      is_for_vendor,
623                                      library_path,
624                                      permitted_path,
625                                      &ns,
626                                      &error_msg);
627  if (!success) {
628    return env->NewStringUTF(error_msg.c_str());
629  }
630#else
631  UNUSED(env, target_sdk_version, class_loader, is_shared, is_for_vendor,
632         library_path, permitted_path);
633#endif
634  return nullptr;
635}
636
637void* OpenNativeLibrary(JNIEnv* env,
638                        int32_t target_sdk_version,
639                        const char* path,
640                        jobject class_loader,
641                        jstring library_path,
642                        bool* needs_native_bridge,
643                        std::string* error_msg) {
644#if defined(__ANDROID__)
645  UNUSED(target_sdk_version);
646  if (class_loader == nullptr) {
647    *needs_native_bridge = false;
648    return dlopen(path, RTLD_NOW);
649  }
650
651  std::lock_guard<std::mutex> guard(g_namespaces_mutex);
652  NativeLoaderNamespace ns;
653
654  if (!g_namespaces->FindNamespaceByClassLoader(env, class_loader, &ns)) {
655    // This is the case where the classloader was not created by ApplicationLoaders
656    // In this case we create an isolated not-shared namespace for it.
657    if (!g_namespaces->Create(env,
658                              target_sdk_version,
659                              class_loader,
660                              false /* is_shared */,
661                              false /* is_for_vendor */,
662                              library_path,
663                              nullptr,
664                              &ns,
665                              error_msg)) {
666      return nullptr;
667    }
668  }
669
670  if (ns.is_android_namespace()) {
671    android_dlextinfo extinfo;
672    extinfo.flags = ANDROID_DLEXT_USE_NAMESPACE;
673    extinfo.library_namespace = ns.get_android_ns();
674
675    void* handle = android_dlopen_ext(path, RTLD_NOW, &extinfo);
676    if (handle == nullptr) {
677      *error_msg = dlerror();
678    }
679    *needs_native_bridge = false;
680    return handle;
681  } else {
682    void* handle = NativeBridgeLoadLibraryExt(path, RTLD_NOW, ns.get_native_bridge_ns());
683    if (handle == nullptr) {
684      *error_msg = NativeBridgeGetError();
685    }
686    *needs_native_bridge = true;
687    return handle;
688  }
689#else
690  UNUSED(env, target_sdk_version, class_loader);
691
692  // Do some best effort to emulate library-path support. It will not
693  // work for dependencies.
694  //
695  // Note: null has a special meaning and must be preserved.
696  std::string c_library_path;  // Empty string by default.
697  if (library_path != nullptr && path != nullptr && path[0] != '/') {
698    ScopedUtfChars library_path_utf_chars(env, library_path);
699    c_library_path = library_path_utf_chars.c_str();
700  }
701
702  std::vector<std::string> library_paths = base::Split(c_library_path, ":");
703
704  for (const std::string& lib_path : library_paths) {
705    *needs_native_bridge = false;
706    const char* path_arg;
707    std::string complete_path;
708    if (path == nullptr) {
709      // Preserve null.
710      path_arg = nullptr;
711    } else {
712      complete_path = lib_path;
713      if (!complete_path.empty()) {
714        complete_path.append("/");
715      }
716      complete_path.append(path);
717      path_arg = complete_path.c_str();
718    }
719    void* handle = dlopen(path_arg, RTLD_NOW);
720    if (handle != nullptr) {
721      return handle;
722    }
723    if (NativeBridgeIsSupported(path_arg)) {
724      *needs_native_bridge = true;
725      handle = NativeBridgeLoadLibrary(path_arg, RTLD_NOW);
726      if (handle != nullptr) {
727        return handle;
728      }
729      *error_msg = NativeBridgeGetError();
730    } else {
731      *error_msg = dlerror();
732    }
733  }
734  return nullptr;
735#endif
736}
737
738bool CloseNativeLibrary(void* handle, const bool needs_native_bridge) {
739    return needs_native_bridge ? NativeBridgeUnloadLibrary(handle) :
740                                 dlclose(handle);
741}
742
743#if defined(__ANDROID__)
744// native_bridge_namespaces are not supported for callers of this function.
745// This function will return nullptr in the case when application is running
746// on native bridge.
747android_namespace_t* FindNamespaceByClassLoader(JNIEnv* env, jobject class_loader) {
748  std::lock_guard<std::mutex> guard(g_namespaces_mutex);
749  NativeLoaderNamespace ns;
750  if (g_namespaces->FindNamespaceByClassLoader(env, class_loader, &ns)) {
751    return ns.is_android_namespace() ? ns.get_android_ns() : nullptr;
752  }
753
754  return nullptr;
755}
756#endif
757
758}; //  android namespace
759