Load namespace configuration from ld.config.txt

This change allows customization of default namespace
configuration for different executables. It also enables
target_sdk_version setup for binaries (note that this
option should explicitly be enabled in ld.config.txt).

Bug: http://b/30706810
Bug: http://b/30435785
Test: run linker-unit-tests/bionic-unit-tests, boot angler
Change-Id: Ibbe87209acf1538fc9cec04944f3d22a190c38f1
diff --git a/linker/tests/linker_config_test.cpp b/linker/tests/linker_config_test.cpp
new file mode 100644
index 0000000..64ab00f
--- /dev/null
+++ b/linker/tests/linker_config_test.cpp
@@ -0,0 +1,178 @@
+/*
+ * Copyright (C) 2017 The Android Open Source Project
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *  * Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *  * Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include <stdlib.h>
+#include <string.h>
+#include <sys/mman.h>
+
+#include <gtest/gtest.h>
+
+#include "../linker_config.h"
+
+#include <unistd.h>
+
+#include <android-base/stringprintf.h>
+#include <android-base/file.h>
+#include <android-base/test_utils.h>
+
+#include "private/ScopeGuard.h"
+
+
+static const char* config_str =
+  "# comment \n"
+  "dir.test = /data/local/tmp\n"
+  "\n"
+  "[test]\n"
+  "\n"
+  "enable.target.sdk.version = true\n"
+  "additional.namespaces=system\n"
+  "namespace.default.isolated = true\n"
+  "namespace.default.search.paths = /vendor/${LIB}\n"
+  "namespace.default.permitted.paths = /vendor/${LIB}\n"
+  "namespace.default.asan.search.paths = /data:/vendor/${LIB}\n"
+  "namespace.default.asan.permitted.paths = /data:/vendor\n"
+  "namespace.default.links = system\n"
+  "namespace.default.link.system.shared_libs = libc.so:libm.so:libdl.so:libstdc++.so\n"
+  "namespace.system.isolated = true\n"
+  "namespace.system.search.paths = /system/${LIB}\n"
+  "namespace.system.permitted.paths = /system/${LIB}\n"
+  "namespace.system.asan.search.paths = /data:/system/${LIB}\n"
+  "namespace.system.asan.permitted.paths = /data:/system\n"
+  "\n";
+
+static bool write_version(const std::string& path, uint32_t version) {
+  std::string content = android::base::StringPrintf("%d", version);
+  return android::base::WriteStringToFile(content, path);
+}
+
+static void run_linker_config_smoke_test(bool is_asan) {
+#if defined(__LP64__)
+  const std::vector<std::string> kExpectedDefaultSearchPath = is_asan ?
+        std::vector<std::string>({ "/data", "/vendor/lib64"}) :
+        std::vector<std::string>({ "/vendor/lib64" });
+
+  const std::vector<std::string> kExpectedDefaultPermittedPath = is_asan ?
+        std::vector<std::string>({ "/data", "/vendor" }) :
+        std::vector<std::string>({ "/vendor/lib64" });
+
+  const std::vector<std::string> kExpectedSystemSearchPath = is_asan ?
+        std::vector<std::string>({ "/data", "/system/lib64" }) :
+        std::vector<std::string>({ "/system/lib64" });
+
+  const std::vector<std::string> kExpectedSystemPermittedPath = is_asan ?
+        std::vector<std::string>({ "/data", "/system" }) :
+        std::vector<std::string>({ "/system/lib64" });
+#else
+  const std::vector<std::string> kExpectedDefaultSearchPath = is_asan ?
+        std::vector<std::string>({ "/data", "/vendor/lib"}) :
+        std::vector<std::string>({ "/vendor/lib" });
+
+  const std::vector<std::string> kExpectedDefaultPermittedPath = is_asan ?
+        std::vector<std::string>({ "/data", "/vendor" }) :
+        std::vector<std::string>({ "/vendor/lib" });
+
+  const std::vector<std::string> kExpectedSystemSearchPath = is_asan ?
+        std::vector<std::string>({ "/data", "/system/lib" }) :
+        std::vector<std::string>({ "/system/lib" });
+
+  const std::vector<std::string> kExpectedSystemPermittedPath = is_asan ?
+        std::vector<std::string>({ "/data", "/system" }) :
+        std::vector<std::string>({ "/system/lib" });
+#endif
+
+  TemporaryFile tmp_file;
+  close(tmp_file.fd);
+  tmp_file.fd = -1;
+
+  android::base::WriteStringToFile(config_str, tmp_file.path);
+
+  TemporaryDir tmp_dir;
+
+  std::string executable_path = std::string(tmp_dir.path) + "/some-binary";
+  std::string version_file = std::string(tmp_dir.path) + "/.version";
+
+  auto file_guard = make_scope_guard([&version_file] {
+    unlink(version_file.c_str());
+  });
+
+  ASSERT_TRUE(write_version(version_file, 113U)) << strerror(errno);
+
+  // read config
+  const Config* config = nullptr;
+  std::string error_msg;
+  ASSERT_TRUE(Config::read_binary_config(tmp_file.path,
+                                         executable_path.c_str(),
+                                         is_asan,
+                                         &config,
+                                         &error_msg)) << error_msg;
+  ASSERT_TRUE(config != nullptr);
+  ASSERT_TRUE(error_msg.empty());
+
+  ASSERT_EQ(113U, config->target_sdk_version());
+
+  const NamespaceConfig* default_ns_config = config->default_namespace_config();
+  ASSERT_TRUE(default_ns_config != nullptr);
+
+  ASSERT_TRUE(default_ns_config->isolated());
+  ASSERT_EQ(kExpectedDefaultSearchPath, default_ns_config->search_paths());
+  ASSERT_EQ(kExpectedDefaultPermittedPath, default_ns_config->permitted_paths());
+
+  const auto& default_ns_links = default_ns_config->links();
+  ASSERT_EQ(1U, default_ns_links.size());
+  ASSERT_EQ("system", default_ns_links[0].ns_name());
+  ASSERT_EQ("libc.so:libm.so:libdl.so:libstdc++.so", default_ns_links[0].shared_libs());
+
+  auto& ns_configs = config->namespace_configs();
+  ASSERT_EQ(2U, ns_configs.size());
+
+  // find second namespace
+  const NamespaceConfig* ns_system = nullptr;
+  for (auto& ns : ns_configs) {
+    std::string ns_name = ns->name();
+    ASSERT_TRUE(ns_name == "system" || ns_name == "default")
+        << "unexpected ns name: " << ns->name();
+
+    if (ns_name == "system") {
+      ns_system = ns.get();
+    }
+  }
+
+  ASSERT_TRUE(ns_system != nullptr) << "system namespace was not found";
+
+  ASSERT_TRUE(ns_system->isolated());
+  ASSERT_EQ(kExpectedSystemSearchPath, ns_system->search_paths());
+  ASSERT_EQ(kExpectedSystemPermittedPath, ns_system->permitted_paths());
+}
+
+TEST(linker_config, smoke) {
+  run_linker_config_smoke_test(false);
+}
+
+TEST(linker_config, asan_smoke) {
+  run_linker_config_smoke_test(true);
+}