Merge "Enable vold to set level from user."

FsCrypt.cpp

@@ -791,6 +791,11 @@ bool fscrypt_lock_user_key(userid_t user_id) {
 
 static bool prepare_subdirs(const std::string& action, const std::string& volume_uuid,
                             userid_t user_id, int flags) {
+    // TODO(b/141677108): Remove this & make it the default behavior
+    if (android::base::GetProperty("ro.vold.level_from_user", "0") == "1") {
+        flags |= android::os::IVold::STORAGE_FLAG_LEVEL_FROM_USER;
+    }
+
     if (0 != android::vold::ForkExecvp(
                  std::vector<std::string>{prepare_subdirs_path, action, volume_uuid,
                                           std::to_string(user_id), std::to_string(flags)})) {

binder/android/os/IVold.aidl

@@ -164,6 +164,7 @@ interface IVold {
 
     const int STORAGE_FLAG_DE = 1;
     const int STORAGE_FLAG_CE = 2;
+    const int STORAGE_FLAG_LEVEL_FROM_USER = 4;
 
     const int REMOUNT_MODE_NONE = 0;
     const int REMOUNT_MODE_DEFAULT = 1;

vold_prepare_subdirs.cpp

@@ -54,20 +54,33 @@ static bool valid_uuid(const std::string& s) {
     return s.size() < 40 && s.find_first_not_of("0123456789abcdefABCDEF-_") == std::string::npos;
 }
 
-static bool prepare_dir(struct selabel_handle* sehandle, mode_t mode, uid_t uid, gid_t gid,
+static bool prepare_dir_for_user(struct selabel_handle* sehandle, mode_t mode, uid_t uid, gid_t gid,
-                        const std::string& path) {
+                                 const std::string& path, uid_t user_id) {
     auto clearfscreatecon = android::base::make_scope_guard([] { setfscreatecon(nullptr); });
     auto secontext = std::unique_ptr<char, void (*)(char*)>(nullptr, freecon);
-    char* tmp_secontext;
+    if (sehandle) {
-    if (sehandle && selabel_lookup(sehandle, &tmp_secontext, path.c_str(), S_IFDIR) == 0) {
+        char* tmp_secontext;
-        secontext.reset(tmp_secontext);
+
+        if (selabel_lookup(sehandle, &tmp_secontext, path.c_str(), S_IFDIR) == 0) {
+            secontext.reset(tmp_secontext);
+
+            if (user_id != (uid_t)-1) {
+                if (selinux_android_context_with_level(secontext.get(), &tmp_secontext, user_id,
+                                                       (uid_t)-1) != 0) {
+                    PLOG(ERROR) << "Unable to create context with level for: " << path;
+                    return false;
+                }
+                secontext.reset(tmp_secontext);  // Free the context
+            }
+        }
     }
+
     LOG(DEBUG) << "Setting up mode " << std::oct << mode << std::dec << " uid " << uid << " gid "
                << gid << " context " << (secontext ? secontext.get() : "null")
                << " on path: " << path;
     if (secontext) {
         if (setfscreatecon(secontext.get()) != 0) {
-            PLOG(ERROR) << "Unable to read setfscreatecon for: " << path;
+            PLOG(ERROR) << "Unable to setfscreatecon for: " << path;
             return false;
         }
     }
@@ -93,6 +106,11 @@ static bool prepare_dir(struct selabel_handle* sehandle, mode_t mode, uid_t uid,
     return true;
 }
 
+static bool prepare_dir(struct selabel_handle* sehandle, mode_t mode, uid_t uid, gid_t gid,
+                        const std::string& path) {
+    return prepare_dir_for_user(sehandle, mode, uid, gid, path, (uid_t)-1);
+}
+
 static bool rmrf_contents(const std::string& path) {
     auto dirp = std::unique_ptr<DIR, int (*)(DIR*)>(opendir(path.c_str()), closedir);
     if (!dirp) {
@@ -148,8 +166,17 @@ static bool prepare_apex_subdirs(struct selabel_handle* sehandle, const std::str
 static bool prepare_subdirs(const std::string& volume_uuid, int user_id, int flags) {
     struct selabel_handle* sehandle = selinux_android_file_context_handle();
 
-    if (volume_uuid.empty()) {
+    const uid_t user_for_level =
-        if (flags & android::os::IVold::STORAGE_FLAG_DE) {
+            (flags & android::os::IVold::STORAGE_FLAG_LEVEL_FROM_USER) ? user_id : -1;
+
+    if (flags & android::os::IVold::STORAGE_FLAG_DE) {
+        auto user_de_path = android::vold::BuildDataUserDePath(volume_uuid, user_id);
+        if (!prepare_dir_for_user(sehandle, 0771, AID_SYSTEM, AID_SYSTEM, user_de_path,
+                                  user_for_level)) {
+            return false;
+        }
+
+        if (volume_uuid.empty()) {
             auto misc_de_path = android::vold::BuildDataMiscDePath(user_id);
             if (!prepare_dir(sehandle, 0700, 0, 0, misc_de_path + "/vold")) return false;
             if (!prepare_dir(sehandle, 0700, 0, 0, misc_de_path + "/storaged")) return false;
@@ -158,6 +185,12 @@ static bool prepare_subdirs(const std::string& volume_uuid, int user_id, int fla
             prepare_dir(sehandle, 0700, 0, 0, misc_de_path + "/apexrollback");
             prepare_apex_subdirs(sehandle, misc_de_path);
 
+            auto profiles_de_path = android::vold::BuildDataProfilesDePath(user_id);
+            if (!prepare_dir_for_user(sehandle, 0771, AID_SYSTEM, AID_SYSTEM, profiles_de_path,
+                                      user_for_level)) {
+                return false;
+            }
+
             auto vendor_de_path = android::vold::BuildDataVendorDePath(user_id);
             if (!prepare_dir(sehandle, 0700, AID_SYSTEM, AID_SYSTEM, vendor_de_path + "/fpdata")) {
                 return false;
@@ -167,11 +200,20 @@ static bool prepare_subdirs(const std::string& volume_uuid, int user_id, int fla
                 return false;
             }
         }
-        if (flags & android::os::IVold::STORAGE_FLAG_CE) {
+    }
+    if (flags & android::os::IVold::STORAGE_FLAG_CE) {
+        auto user_ce_path = android::vold::BuildDataUserCePath(volume_uuid, user_id);
+        if (!prepare_dir_for_user(sehandle, 0771, AID_SYSTEM, AID_SYSTEM, user_ce_path,
+                                  user_for_level)) {
+            return false;
+        }
+
+        if (volume_uuid.empty()) {
             auto misc_ce_path = android::vold::BuildDataMiscCePath(user_id);
             if (!prepare_dir(sehandle, 0700, 0, 0, misc_ce_path + "/vold")) return false;
             if (!prepare_dir(sehandle, 0700, 0, 0, misc_ce_path + "/storaged")) return false;
             if (!prepare_dir(sehandle, 0700, 0, 0, misc_ce_path + "/rollback")) return false;
+
             // TODO: Return false if this returns false once sure this should succeed.
             prepare_dir(sehandle, 0700, 0, 0, misc_ce_path + "/apexrollback");
             prepare_apex_subdirs(sehandle, misc_ce_path);