blob: 712f544c35b346a2a226261c65e662b17f698111 [file] [log] [blame]
Jeff Sharkeyd2c96e72015-11-08 17:56:23 -08001/*
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
Eric Biggersa701c452018-10-23 13:06:55 -070017#include "FsCrypt.h"
Paul Lawrence731a7a22015-04-28 22:14:15 +000018
Paul Crowley1ef25582016-01-21 20:26:12 +000019#include "KeyStorage.h"
Paul Crowleyf71ace32016-06-02 11:01:19 -070020#include "KeyUtil.h"
Jeff Sharkeyd2c96e72015-11-08 17:56:23 -080021#include "Utils.h"
Paul Crowleya7ca40b2017-10-06 14:29:33 -070022#include "VoldUtil.h"
23
Paul Crowleya3630362016-05-17 14:17:56 -070024#include <algorithm>
Paul Lawrence731a7a22015-04-28 22:14:15 +000025#include <map>
Barani Muthukumaranb1927c22019-10-31 22:59:34 -070026#include <optional>
Paul Crowleyb1f3d242016-01-28 10:09:46 +000027#include <set>
Paul Lawrencefd7db732015-04-10 07:48:51 -070028#include <sstream>
Paul Crowleydf528a72016-03-09 09:31:37 -080029#include <string>
Paul Crowleyf71ace32016-06-02 11:01:19 -070030#include <vector>
Paul Lawrence731a7a22015-04-28 22:14:15 +000031
Paul Crowleydf528a72016-03-09 09:31:37 -080032#include <dirent.h>
33#include <errno.h>
34#include <fcntl.h>
Paul Crowleya3630362016-05-17 14:17:56 -070035#include <limits.h>
Jeff Sharkey7a9dd952016-01-12 16:52:16 -070036#include <selinux/android.h>
Paul Crowleydf528a72016-03-09 09:31:37 -080037#include <sys/mount.h>
38#include <sys/stat.h>
39#include <sys/types.h>
Paul Crowley14c8c072018-09-18 13:30:21 -070040#include <unistd.h>
Paul Lawrence731a7a22015-04-28 22:14:15 +000041
Paul Crowley480fcd22015-08-24 14:53:28 +010042#include <private/android_filesystem_config.h>
43
Paul Crowley82b41ff2017-10-20 08:17:54 -070044#include "android/os/IVold.h"
45
Paul Lawrence731a7a22015-04-28 22:14:15 +000046#include "cryptfs.h"
47
Jeff Sharkey7a9dd952016-01-12 16:52:16 -070048#define EMULATED_USES_SELINUX 0
Jeff Sharkeybe70c9a2016-04-14 20:45:16 -060049#define MANAGE_MISC_DIRS 0
Jeff Sharkey7a9dd952016-01-12 16:52:16 -070050
Jeff Sharkeyd2c96e72015-11-08 17:56:23 -080051#include <cutils/fs.h>
Paul Crowleyf71ace32016-06-02 11:01:19 -070052#include <cutils/properties.h>
53
Eric Biggersa701c452018-10-23 13:06:55 -070054#include <fscrypt/fscrypt.h>
Elliott Hughesc3bda182017-05-09 17:01:04 -070055#include <keyutils.h>
Jeff Sharkeyd2c96e72015-11-08 17:56:23 -080056
Elliott Hughes7e128fb2015-12-04 15:50:53 -080057#include <android-base/file.h>
Elliott Hughes6bf05472015-12-04 17:55:33 -080058#include <android-base/logging.h>
Paul Crowley3aa914d2017-10-09 16:35:51 -070059#include <android-base/properties.h>
Elliott Hughes7e128fb2015-12-04 15:50:53 -080060#include <android-base/stringprintf.h>
Eric Biggers83a73d72019-09-30 13:06:47 -070061#include <android-base/strings.h>
Jieb6698d52018-11-12 15:26:02 +080062#include <android-base/unique_fd.h>
Paul Lawrence731a7a22015-04-28 22:14:15 +000063
Jeff Sharkeyd2c96e72015-11-08 17:56:23 -080064using android::base::StringPrintf;
Tom Cherry4c5bde22019-01-29 14:34:01 -080065using android::fs_mgr::GetEntryForMountPoint;
Paul Crowley77df7f22020-01-23 15:29:30 -080066using android::vold::BuildDataPath;
Paul Crowley05720802016-02-08 15:55:41 +000067using android::vold::kEmptyAuthentication;
Pavel Grafove2e2d302017-08-01 17:15:53 +010068using android::vold::KeyBuffer;
Tommy Chiua98464f2019-03-26 14:14:19 +080069using android::vold::writeStringToFile;
Paul Crowley5e53ff62019-10-24 14:55:17 -070070using namespace android::fscrypt;
Jeff Sharkeyd2c96e72015-11-08 17:56:23 -080071
Paul Lawrence731a7a22015-04-28 22:14:15 +000072namespace {
Andrew Scull7ec25c72016-10-31 10:28:25 +000073
Eric Biggersa701c452018-10-23 13:06:55 -070074const std::string device_key_dir = std::string() + DATA_MNT_POINT + fscrypt_unencrypted_folder;
Paul Crowleydf528a72016-03-09 09:31:37 -080075const std::string device_key_path = device_key_dir + "/key";
76const std::string device_key_temp = device_key_dir + "/temp";
Paul Lawrence5a06a642016-02-03 13:39:13 -080077
Paul Crowleydf528a72016-03-09 09:31:37 -080078const std::string user_key_dir = std::string() + DATA_MNT_POINT + "/misc/vold/user_keys";
79const std::string user_key_temp = user_key_dir + "/temp";
Paul Crowley82b41ff2017-10-20 08:17:54 -070080const std::string prepare_subdirs_path = "/system/bin/vold_prepare_subdirs";
Paul Crowley285956f2016-01-20 13:12:38 +000081
Paul Crowley26a53882017-10-26 11:16:39 -070082const std::string systemwide_volume_key_dir =
83 std::string() + DATA_MNT_POINT + "/misc/vold/volume_keys";
84
Paul Crowleyc8a3ef32019-09-11 15:00:08 -070085bool s_systemwide_keys_initialized = false;
Paul Lawrence7b6b5652016-02-02 11:14:59 -080086
Paul Crowleydf528a72016-03-09 09:31:37 -080087// Some users are ephemeral, don't try to wipe their keys from disk
88std::set<userid_t> s_ephemeral_users;
Paul Lawrenceaec34df2016-02-03 10:52:41 -080089
Paul Crowley77df7f22020-01-23 15:29:30 -080090// Map user ids to encryption policies
91std::map<userid_t, EncryptionPolicy> s_de_policies;
92std::map<userid_t, EncryptionPolicy> s_ce_policies;
Paul Lawrence731a7a22015-04-28 22:14:15 +000093
Paul Crowley14c8c072018-09-18 13:30:21 -070094} // namespace
Paul Lawrence731a7a22015-04-28 22:14:15 +000095
Eric Biggersa701c452018-10-23 13:06:55 -070096static bool fscrypt_is_emulated() {
Paul Crowley38132a12016-02-09 09:50:32 +000097 return property_get_bool("persist.sys.emulate_fbe", false);
98}
99
Paul Crowley3b71fc52017-10-09 10:55:21 -0700100static const char* escape_empty(const std::string& value) {
101 return value.empty() ? "null" : value.c_str();
Paul Lawrence731a7a22015-04-28 22:14:15 +0000102}
103
Paul Crowleyb92f83c2016-02-01 14:10:43 +0000104static std::string get_de_key_path(userid_t user_id) {
105 return StringPrintf("%s/de/%d", user_key_dir.c_str(), user_id);
106}
107
Paul Crowleya3630362016-05-17 14:17:56 -0700108static std::string get_ce_key_directory_path(userid_t user_id) {
109 return StringPrintf("%s/ce/%d", user_key_dir.c_str(), user_id);
110}
111
112// Returns the keys newest first
113static std::vector<std::string> get_ce_key_paths(const std::string& directory_path) {
114 auto dirp = std::unique_ptr<DIR, int (*)(DIR*)>(opendir(directory_path.c_str()), closedir);
115 if (!dirp) {
116 PLOG(ERROR) << "Unable to open ce key directory: " + directory_path;
117 return std::vector<std::string>();
118 }
119 std::vector<std::string> result;
120 for (;;) {
121 errno = 0;
122 auto const entry = readdir(dirp.get());
123 if (!entry) {
124 if (errno) {
125 PLOG(ERROR) << "Unable to read ce key directory: " + directory_path;
126 return std::vector<std::string>();
127 }
128 break;
129 }
130 if (entry->d_type != DT_DIR || entry->d_name[0] != 'c') {
131 LOG(DEBUG) << "Skipping non-key " << entry->d_name;
132 continue;
133 }
134 result.emplace_back(directory_path + "/" + entry->d_name);
135 }
136 std::sort(result.begin(), result.end());
137 std::reverse(result.begin(), result.end());
138 return result;
139}
140
141static std::string get_ce_key_current_path(const std::string& directory_path) {
142 return directory_path + "/current";
143}
144
145static bool get_ce_key_new_path(const std::string& directory_path,
Paul Crowley14c8c072018-09-18 13:30:21 -0700146 const std::vector<std::string>& paths, std::string* ce_key_path) {
Paul Crowleya3630362016-05-17 14:17:56 -0700147 if (paths.empty()) {
148 *ce_key_path = get_ce_key_current_path(directory_path);
149 return true;
150 }
151 for (unsigned int i = 0; i < UINT_MAX; i++) {
152 auto const candidate = StringPrintf("%s/cx%010u", directory_path.c_str(), i);
153 if (paths[0] < candidate) {
154 *ce_key_path = candidate;
155 return true;
156 }
157 }
158 return false;
159}
160
161// Discard all keys but the named one; rename it to canonical name.
162// No point in acting on errors in this; ignore them.
Paul Crowley14c8c072018-09-18 13:30:21 -0700163static void fixate_user_ce_key(const std::string& directory_path, const std::string& to_fix,
Paul Crowleya3630362016-05-17 14:17:56 -0700164 const std::vector<std::string>& paths) {
Paul Crowley14c8c072018-09-18 13:30:21 -0700165 for (auto const other_path : paths) {
Paul Crowleya3630362016-05-17 14:17:56 -0700166 if (other_path != to_fix) {
167 android::vold::destroyKey(other_path);
168 }
169 }
170 auto const current_path = get_ce_key_current_path(directory_path);
171 if (to_fix != current_path) {
172 LOG(DEBUG) << "Renaming " << to_fix << " to " << current_path;
173 if (rename(to_fix.c_str(), current_path.c_str()) != 0) {
174 PLOG(WARNING) << "Unable to rename " << to_fix << " to " << current_path;
Jieb6698d52018-11-12 15:26:02 +0800175 return;
Paul Crowleya3630362016-05-17 14:17:56 -0700176 }
177 }
Paul Crowley621d9b92018-12-07 15:36:09 -0800178 android::vold::FsyncDirectory(directory_path);
Paul Crowleya3630362016-05-17 14:17:56 -0700179}
180
181static bool read_and_fixate_user_ce_key(userid_t user_id,
182 const android::vold::KeyAuthentication& auth,
Paul Crowley14c8c072018-09-18 13:30:21 -0700183 KeyBuffer* ce_key) {
Paul Crowleya3630362016-05-17 14:17:56 -0700184 auto const directory_path = get_ce_key_directory_path(user_id);
185 auto const paths = get_ce_key_paths(directory_path);
Paul Crowley14c8c072018-09-18 13:30:21 -0700186 for (auto const ce_key_path : paths) {
Paul Crowleya3630362016-05-17 14:17:56 -0700187 LOG(DEBUG) << "Trying user CE key " << ce_key_path;
188 if (android::vold::retrieveKey(ce_key_path, auth, ce_key)) {
189 LOG(DEBUG) << "Successfully retrieved key";
190 fixate_user_ce_key(directory_path, ce_key_path, paths);
191 return true;
192 }
193 }
194 LOG(ERROR) << "Failed to find working ce key for user " << user_id;
195 return false;
Paul Crowleyb33e8872015-05-19 12:34:09 +0100196}
197
Eric Biggers83a73d72019-09-30 13:06:47 -0700198// Retrieve the options to use for encryption policies on the /data filesystem.
Paul Crowley77df7f22020-01-23 15:29:30 -0800199static bool get_data_file_encryption_options(EncryptionOptions* options) {
Eric Biggers83a73d72019-09-30 13:06:47 -0700200 auto entry = GetEntryForMountPoint(&fstab_default, DATA_MNT_POINT);
201 if (entry == nullptr) {
Paul Crowley77df7f22020-01-23 15:29:30 -0800202 LOG(ERROR) << "No mount point entry for " << DATA_MNT_POINT;
203 return false;
Eric Biggers83a73d72019-09-30 13:06:47 -0700204 }
Paul Crowleya50f6c32019-10-24 23:21:44 -0700205 if (!ParseOptions(entry->encryption_options, options)) {
206 LOG(ERROR) << "Unable to parse encryption options for " << DATA_MNT_POINT ": "
207 << entry->encryption_options;
Paul Crowley77df7f22020-01-23 15:29:30 -0800208 return false;
Paul Crowleya50f6c32019-10-24 23:21:44 -0700209 }
Paul Crowley77df7f22020-01-23 15:29:30 -0800210 return true;
Eric Biggers83a73d72019-09-30 13:06:47 -0700211}
212
213// Retrieve the options to use for encryption policies on adoptable storage.
Paul Crowley5e53ff62019-10-24 14:55:17 -0700214static bool get_volume_file_encryption_options(EncryptionOptions* options) {
Paul Crowleyf612b8b2019-10-24 22:52:02 -0700215 auto contents_mode =
216 android::base::GetProperty("ro.crypto.volume.contents_mode", "aes-256-xts");
217 auto filenames_mode =
218 android::base::GetProperty("ro.crypto.volume.filenames_mode", "aes-256-heh");
Paul Crowley77df7f22020-01-23 15:29:30 -0800219 auto options_string = android::base::GetProperty("ro.crypto.volume.options",
220 contents_mode + ":" + filenames_mode + ":v1");
221 if (!ParseOptions(options_string, options)) {
222 LOG(ERROR) << "Unable to parse volume encryption options: " << options_string;
223 return false;
224 }
225 return true;
Eric Biggersf3dc4202019-09-30 13:05:58 -0700226}
227
Paul Crowleydf528a72016-03-09 09:31:37 -0800228static bool read_and_install_user_ce_key(userid_t user_id,
229 const android::vold::KeyAuthentication& auth) {
Paul Crowley77df7f22020-01-23 15:29:30 -0800230 if (s_ce_policies.count(user_id) != 0) return true;
231 EncryptionOptions options;
232 if (!get_data_file_encryption_options(&options)) return false;
Pavel Grafove2e2d302017-08-01 17:15:53 +0100233 KeyBuffer ce_key;
Paul Crowleya3630362016-05-17 14:17:56 -0700234 if (!read_and_fixate_user_ce_key(user_id, auth, &ce_key)) return false;
Paul Crowley77df7f22020-01-23 15:29:30 -0800235 EncryptionPolicy ce_policy;
236 if (!installKey(DATA_MNT_POINT, options, ce_key, &ce_policy)) return false;
237 s_ce_policies[user_id] = ce_policy;
Paul Crowleyb1f3d242016-01-28 10:09:46 +0000238 LOG(DEBUG) << "Installed ce key for user " << user_id;
Paul Crowley1ef25582016-01-21 20:26:12 +0000239 return true;
Paul Crowley285956f2016-01-20 13:12:38 +0000240}
241
Paul Crowleydf528a72016-03-09 09:31:37 -0800242static bool prepare_dir(const std::string& dir, mode_t mode, uid_t uid, gid_t gid) {
Paul Crowleyb1f3d242016-01-28 10:09:46 +0000243 LOG(DEBUG) << "Preparing: " << dir;
Paul Crowley13ffd8e2016-01-27 14:30:22 +0000244 if (fs_prepare_dir(dir.c_str(), mode, uid, gid) != 0) {
245 PLOG(ERROR) << "Failed to prepare " << dir;
Paul Crowley285956f2016-01-20 13:12:38 +0000246 return false;
247 }
Paul Crowley13ffd8e2016-01-27 14:30:22 +0000248 return true;
249}
250
Jeff Sharkeybe70c9a2016-04-14 20:45:16 -0600251static bool destroy_dir(const std::string& dir) {
252 LOG(DEBUG) << "Destroying: " << dir;
253 if (rmdir(dir.c_str()) != 0 && errno != ENOENT) {
254 PLOG(ERROR) << "Failed to destroy " << dir;
255 return false;
256 }
257 return true;
258}
259
Paul Crowleyb1f3d242016-01-28 10:09:46 +0000260// NB this assumes that there is only one thread listening for crypt commands, because
261// it creates keys in a fixed location.
Paul Crowleyb92f83c2016-02-01 14:10:43 +0000262static bool create_and_install_user_keys(userid_t user_id, bool create_ephemeral) {
Paul Crowley77df7f22020-01-23 15:29:30 -0800263 EncryptionOptions options;
264 if (!get_data_file_encryption_options(&options)) return false;
Pavel Grafove2e2d302017-08-01 17:15:53 +0100265 KeyBuffer de_key, ce_key;
Paul Crowleyf71ace32016-06-02 11:01:19 -0700266 if (!android::vold::randomKey(&de_key)) return false;
267 if (!android::vold::randomKey(&ce_key)) return false;
Paul Crowleyb1f3d242016-01-28 10:09:46 +0000268 if (create_ephemeral) {
269 // If the key should be created as ephemeral, don't store it.
270 s_ephemeral_users.insert(user_id);
271 } else {
Paul Crowleya3630362016-05-17 14:17:56 -0700272 auto const directory_path = get_ce_key_directory_path(user_id);
273 if (!prepare_dir(directory_path, 0700, AID_ROOT, AID_ROOT)) return false;
274 auto const paths = get_ce_key_paths(directory_path);
275 std::string ce_key_path;
276 if (!get_ce_key_new_path(directory_path, paths, &ce_key_path)) return false;
Paul Crowley14c8c072018-09-18 13:30:21 -0700277 if (!android::vold::storeKeyAtomically(ce_key_path, user_key_temp, kEmptyAuthentication,
278 ce_key))
279 return false;
Paul Crowleya3630362016-05-17 14:17:56 -0700280 fixate_user_ce_key(directory_path, ce_key_path, paths);
281 // Write DE key second; once this is written, all is good.
Paul Crowleyf71ace32016-06-02 11:01:19 -0700282 if (!android::vold::storeKeyAtomically(get_de_key_path(user_id), user_key_temp,
Paul Crowley14c8c072018-09-18 13:30:21 -0700283 kEmptyAuthentication, de_key))
284 return false;
Paul Crowley95376d62015-05-06 15:04:43 +0100285 }
Paul Crowley77df7f22020-01-23 15:29:30 -0800286 EncryptionPolicy de_policy;
287 if (!installKey(DATA_MNT_POINT, options, de_key, &de_policy)) return false;
288 s_de_policies[user_id] = de_policy;
289 EncryptionPolicy ce_policy;
290 if (!installKey(DATA_MNT_POINT, options, ce_key, &ce_policy)) return false;
291 s_ce_policies[user_id] = ce_policy;
Paul Crowleyb92f83c2016-02-01 14:10:43 +0000292 LOG(DEBUG) << "Created keys for user " << user_id;
Paul Crowleyb1f3d242016-01-28 10:09:46 +0000293 return true;
294}
295
Paul Crowley77df7f22020-01-23 15:29:30 -0800296static bool lookup_policy(const std::map<userid_t, EncryptionPolicy>& key_map, userid_t user_id,
297 EncryptionPolicy* policy) {
Paul Crowleyb1f3d242016-01-28 10:09:46 +0000298 auto refi = key_map.find(user_id);
299 if (refi == key_map.end()) {
Eric Biggersd1034042019-04-02 10:38:15 -0700300 LOG(DEBUG) << "Cannot find key for " << user_id;
Paul Crowleyb1f3d242016-01-28 10:09:46 +0000301 return false;
302 }
Paul Crowley77df7f22020-01-23 15:29:30 -0800303 *policy = refi->second;
Paul Crowleyb1f3d242016-01-28 10:09:46 +0000304 return true;
305}
306
Paul Crowleydf528a72016-03-09 09:31:37 -0800307static bool is_numeric(const char* name) {
308 for (const char* p = name; *p != '\0'; p++) {
309 if (!isdigit(*p)) return false;
Paul Crowleyb92f83c2016-02-01 14:10:43 +0000310 }
311 return true;
312}
313
314static bool load_all_de_keys() {
Paul Crowley77df7f22020-01-23 15:29:30 -0800315 EncryptionOptions options;
316 if (!get_data_file_encryption_options(&options)) return false;
Paul Crowleyb92f83c2016-02-01 14:10:43 +0000317 auto de_dir = user_key_dir + "/de";
Paul Crowleydf528a72016-03-09 09:31:37 -0800318 auto dirp = std::unique_ptr<DIR, int (*)(DIR*)>(opendir(de_dir.c_str()), closedir);
Paul Crowleyb92f83c2016-02-01 14:10:43 +0000319 if (!dirp) {
320 PLOG(ERROR) << "Unable to read de key directory";
321 return false;
322 }
323 for (;;) {
324 errno = 0;
325 auto entry = readdir(dirp.get());
326 if (!entry) {
327 if (errno) {
328 PLOG(ERROR) << "Unable to read de key directory";
329 return false;
330 }
331 break;
332 }
333 if (entry->d_type != DT_DIR || !is_numeric(entry->d_name)) {
334 LOG(DEBUG) << "Skipping non-de-key " << entry->d_name;
335 continue;
336 }
Jeff Sharkey95440eb2017-09-18 18:19:28 -0600337 userid_t user_id = std::stoi(entry->d_name);
Paul Crowley77df7f22020-01-23 15:29:30 -0800338 if (s_de_policies.count(user_id) == 0) {
Paul Crowley05720802016-02-08 15:55:41 +0000339 auto key_path = de_dir + "/" + entry->d_name;
Paul Crowley77df7f22020-01-23 15:29:30 -0800340 KeyBuffer de_key;
341 if (!android::vold::retrieveKey(key_path, kEmptyAuthentication, &de_key)) return false;
342 EncryptionPolicy de_policy;
343 if (!installKey(DATA_MNT_POINT, options, de_key, &de_policy)) return false;
344 s_de_policies[user_id] = de_policy;
Paul Crowleyb92f83c2016-02-01 14:10:43 +0000345 LOG(DEBUG) << "Installed de key for user " << user_id;
346 }
347 }
Eric Biggersa701c452018-10-23 13:06:55 -0700348 // fscrypt:TODO: go through all DE directories, ensure that all user dirs have the
Paul Crowleyb92f83c2016-02-01 14:10:43 +0000349 // correct policy set on them, and that no rogue ones exist.
350 return true;
351}
352
Paul Crowleyc8a3ef32019-09-11 15:00:08 -0700353bool fscrypt_initialize_systemwide_keys() {
354 LOG(INFO) << "fscrypt_initialize_systemwide_keys";
Paul Lawrenceaec34df2016-02-03 10:52:41 -0800355
Paul Crowleyc8a3ef32019-09-11 15:00:08 -0700356 if (s_systemwide_keys_initialized) {
Paul Crowley38132a12016-02-09 09:50:32 +0000357 LOG(INFO) << "Already initialized";
Paul Crowley76107cb2016-02-09 10:04:39 +0000358 return true;
Paul Lawrenceaec34df2016-02-03 10:52:41 -0800359 }
Paul Crowley77df7f22020-01-23 15:29:30 -0800360 EncryptionOptions options;
361 if (!get_data_file_encryption_options(&options)) return false;
362
363 KeyBuffer device_key;
364 if (!android::vold::retrieveKey(true, kEmptyAuthentication, device_key_path, device_key_temp,
365 &device_key))
366 return false;
Paul Lawrenceaec34df2016-02-03 10:52:41 -0800367
Paul Crowley5e53ff62019-10-24 14:55:17 -0700368 EncryptionPolicy device_policy;
Paul Crowley77df7f22020-01-23 15:29:30 -0800369 if (!android::vold::installKey(DATA_MNT_POINT, options, device_key, &device_policy))
Eric Biggers83a73d72019-09-30 13:06:47 -0700370 return false;
371
Paul Crowley5e53ff62019-10-24 14:55:17 -0700372 std::string options_string;
373 if (!OptionsToString(device_policy.options, &options_string)) {
374 LOG(ERROR) << "Unable to serialize options";
375 return false;
376 }
Paul Crowley77df7f22020-01-23 15:29:30 -0800377 std::string options_filename = std::string(DATA_MNT_POINT) + fscrypt_key_mode;
Eric Biggers83a73d72019-09-30 13:06:47 -0700378 if (!android::vold::writeStringToFile(options_string, options_filename)) return false;
Paul Lawrence6e410592016-05-24 14:20:38 -0700379
Paul Crowley77df7f22020-01-23 15:29:30 -0800380 std::string ref_filename = std::string(DATA_MNT_POINT) + fscrypt_key_ref;
Paul Crowley5e53ff62019-10-24 14:55:17 -0700381 if (!android::vold::writeStringToFile(device_policy.key_raw_ref, ref_filename)) return false;
Paul Crowleyf71ace32016-06-02 11:01:19 -0700382 LOG(INFO) << "Wrote system DE key reference to:" << ref_filename;
Paul Lawrenceaec34df2016-02-03 10:52:41 -0800383
Paul Crowleyc8a3ef32019-09-11 15:00:08 -0700384 KeyBuffer per_boot_key;
385 if (!android::vold::randomKey(&per_boot_key)) return false;
Paul Crowley77df7f22020-01-23 15:29:30 -0800386 EncryptionPolicy per_boot_policy;
387 if (!android::vold::installKey(DATA_MNT_POINT, options, per_boot_key, &per_boot_policy))
388 return false;
Paul Crowleyc8a3ef32019-09-11 15:00:08 -0700389 std::string per_boot_ref_filename = std::string("/data") + fscrypt_key_per_boot_ref;
Paul Crowley77df7f22020-01-23 15:29:30 -0800390 if (!android::vold::writeStringToFile(per_boot_policy.key_raw_ref, per_boot_ref_filename))
391 return false;
Paul Crowleyc8a3ef32019-09-11 15:00:08 -0700392 LOG(INFO) << "Wrote per boot key reference to:" << per_boot_ref_filename;
393
Tommy Chiua98464f2019-03-26 14:14:19 +0800394 if (!android::vold::FsyncDirectory(device_key_dir)) return false;
Paul Crowleyc8a3ef32019-09-11 15:00:08 -0700395 s_systemwide_keys_initialized = true;
Paul Crowley76107cb2016-02-09 10:04:39 +0000396 return true;
Paul Lawrenceaec34df2016-02-03 10:52:41 -0800397}
398
Eric Biggersa701c452018-10-23 13:06:55 -0700399bool fscrypt_init_user0() {
400 LOG(DEBUG) << "fscrypt_init_user0";
401 if (fscrypt_is_native()) {
Paul Crowley76107cb2016-02-09 10:04:39 +0000402 if (!prepare_dir(user_key_dir, 0700, AID_ROOT, AID_ROOT)) return false;
403 if (!prepare_dir(user_key_dir + "/ce", 0700, AID_ROOT, AID_ROOT)) return false;
404 if (!prepare_dir(user_key_dir + "/de", 0700, AID_ROOT, AID_ROOT)) return false;
Paul Crowleyf71ace32016-06-02 11:01:19 -0700405 if (!android::vold::pathExists(get_de_key_path(0))) {
Paul Crowley76107cb2016-02-09 10:04:39 +0000406 if (!create_and_install_user_keys(0, false)) return false;
Paul Crowley8fb12fd2016-02-01 14:28:12 +0000407 }
Jeff Sharkey47695b22016-02-01 17:02:29 -0700408 // TODO: switch to loading only DE_0 here once framework makes
409 // explicit calls to install DE keys for secondary users
Paul Crowley76107cb2016-02-09 10:04:39 +0000410 if (!load_all_de_keys()) return false;
Paul Crowley8fb12fd2016-02-01 14:28:12 +0000411 }
Jeff Sharkey47695b22016-02-01 17:02:29 -0700412 // We can only safely prepare DE storage here, since CE keys are probably
413 // entangled with user credentials. The framework will always prepare CE
414 // storage once CE keys are installed.
Eric Biggersa701c452018-10-23 13:06:55 -0700415 if (!fscrypt_prepare_user_storage("", 0, 0, android::os::IVold::STORAGE_FLAG_DE)) {
Jeff Sharkey47695b22016-02-01 17:02:29 -0700416 LOG(ERROR) << "Failed to prepare user 0 storage";
Paul Crowley76107cb2016-02-09 10:04:39 +0000417 return false;
Jeff Sharkey47695b22016-02-01 17:02:29 -0700418 }
Jeff Sharkey0754a452016-02-08 12:21:42 -0700419
420 // If this is a non-FBE device that recently left an emulated mode,
421 // restore user data directories to known-good state.
Eric Biggersa701c452018-10-23 13:06:55 -0700422 if (!fscrypt_is_native() && !fscrypt_is_emulated()) {
423 fscrypt_unlock_user_key(0, 0, "!", "!");
Jeff Sharkey0754a452016-02-08 12:21:42 -0700424 }
425
Paul Crowley76107cb2016-02-09 10:04:39 +0000426 return true;
Paul Crowley8fb12fd2016-02-01 14:28:12 +0000427}
428
Eric Biggersa701c452018-10-23 13:06:55 -0700429bool fscrypt_vold_create_user_key(userid_t user_id, int serial, bool ephemeral) {
430 LOG(DEBUG) << "fscrypt_vold_create_user_key for " << user_id << " serial " << serial;
431 if (!fscrypt_is_native()) {
Paul Crowley76107cb2016-02-09 10:04:39 +0000432 return true;
Paul Crowleyea62e262016-01-28 12:23:53 +0000433 }
Paul Crowleyb1f3d242016-01-28 10:09:46 +0000434 // FIXME test for existence of key that is not loaded yet
Paul Crowley77df7f22020-01-23 15:29:30 -0800435 if (s_ce_policies.count(user_id) != 0) {
Eric Biggersa701c452018-10-23 13:06:55 -0700436 LOG(ERROR) << "Already exists, can't fscrypt_vold_create_user_key for " << user_id
Paul Crowleydf528a72016-03-09 09:31:37 -0800437 << " serial " << serial;
Paul Crowley285956f2016-01-20 13:12:38 +0000438 // FIXME should we fail the command?
Paul Crowley76107cb2016-02-09 10:04:39 +0000439 return true;
Jeff Sharkeyd2c96e72015-11-08 17:56:23 -0800440 }
Paul Crowleyb92f83c2016-02-01 14:10:43 +0000441 if (!create_and_install_user_keys(user_id, ephemeral)) {
Paul Crowley76107cb2016-02-09 10:04:39 +0000442 return false;
Paul Crowley285956f2016-01-20 13:12:38 +0000443 }
Paul Crowley76107cb2016-02-09 10:04:39 +0000444 return true;
Jeff Sharkeyd2c96e72015-11-08 17:56:23 -0800445}
446
Eric Biggersce368682019-04-03 15:44:06 -0700447// "Lock" all encrypted directories whose key has been removed. This is needed
Eric Biggersf3dc4202019-09-30 13:05:58 -0700448// in the case where the keys are being put in the session keyring (rather in
449// the newer filesystem-level keyrings), because removing a key from the session
450// keyring doesn't affect inodes in the kernel's inode cache whose per-file key
451// was already set up. So to remove the per-file keys and make the files
452// "appear encrypted", these inodes must be evicted.
Eric Biggersce368682019-04-03 15:44:06 -0700453//
454// To do this, sync() to clean all dirty inodes, then drop all reclaimable slab
455// objects systemwide. This is overkill, but it's the best available method
456// currently. Don't use drop_caches mode "3" because that also evicts pagecache
457// for in-use files; all files relevant here are already closed and sync'ed.
Eric Biggersf3dc4202019-09-30 13:05:58 -0700458static void drop_caches_if_needed() {
459 if (android::vold::isFsKeyringSupported()) {
460 return;
461 }
Pavel Grafovb350ed02017-07-27 17:34:57 +0100462 sync();
Eric Biggersce368682019-04-03 15:44:06 -0700463 if (!writeStringToFile("2", "/proc/sys/vm/drop_caches")) {
Pavel Grafovb350ed02017-07-27 17:34:57 +0100464 PLOG(ERROR) << "Failed to drop caches during key eviction";
465 }
466}
467
Andrew Scull7ec25c72016-10-31 10:28:25 +0000468static bool evict_ce_key(userid_t user_id) {
Andrew Scull7ec25c72016-10-31 10:28:25 +0000469 bool success = true;
Paul Crowley77df7f22020-01-23 15:29:30 -0800470 EncryptionPolicy policy;
Andrew Scull7ec25c72016-10-31 10:28:25 +0000471 // If we haven't loaded the CE key, no need to evict it.
Paul Crowley77df7f22020-01-23 15:29:30 -0800472 if (lookup_policy(s_ce_policies, user_id, &policy)) {
473 success &= android::vold::evictKey(DATA_MNT_POINT, policy);
Eric Biggersf3dc4202019-09-30 13:05:58 -0700474 drop_caches_if_needed();
Andrew Scull7ec25c72016-10-31 10:28:25 +0000475 }
Paul Crowley77df7f22020-01-23 15:29:30 -0800476 s_ce_policies.erase(user_id);
Andrew Scull7ec25c72016-10-31 10:28:25 +0000477 return success;
478}
479
Eric Biggersa701c452018-10-23 13:06:55 -0700480bool fscrypt_destroy_user_key(userid_t user_id) {
481 LOG(DEBUG) << "fscrypt_destroy_user_key(" << user_id << ")";
482 if (!fscrypt_is_native()) {
Paul Crowley76107cb2016-02-09 10:04:39 +0000483 return true;
Paul Crowleyea62e262016-01-28 12:23:53 +0000484 }
Paul Crowleyb1f3d242016-01-28 10:09:46 +0000485 bool success = true;
Andrew Scull7ec25c72016-10-31 10:28:25 +0000486 success &= evict_ce_key(user_id);
Paul Crowley77df7f22020-01-23 15:29:30 -0800487 EncryptionPolicy de_policy;
488 success &= lookup_policy(s_de_policies, user_id, &de_policy) &&
489 android::vold::evictKey(DATA_MNT_POINT, de_policy);
490 s_de_policies.erase(user_id);
Paul Crowleyb1f3d242016-01-28 10:09:46 +0000491 auto it = s_ephemeral_users.find(user_id);
492 if (it != s_ephemeral_users.end()) {
493 s_ephemeral_users.erase(it);
Paul Crowley1ef25582016-01-21 20:26:12 +0000494 } else {
Paul Crowley14c8c072018-09-18 13:30:21 -0700495 for (auto const path : get_ce_key_paths(get_ce_key_directory_path(user_id))) {
Paul Crowleya3630362016-05-17 14:17:56 -0700496 success &= android::vold::destroyKey(path);
497 }
Paul Crowleyab0b56a2016-07-19 15:29:53 -0700498 auto de_key_path = get_de_key_path(user_id);
Paul Crowleyf71ace32016-06-02 11:01:19 -0700499 if (android::vold::pathExists(de_key_path)) {
Paul Crowleyab0b56a2016-07-19 15:29:53 -0700500 success &= android::vold::destroyKey(de_key_path);
501 } else {
502 LOG(INFO) << "Not present so not erasing: " << de_key_path;
503 }
Lenka Trochtova395039f2015-11-25 10:13:03 +0100504 }
Paul Crowley76107cb2016-02-09 10:04:39 +0000505 return success;
Paul Crowleyb33e8872015-05-19 12:34:09 +0100506}
Jeff Sharkeyd2c96e72015-11-08 17:56:23 -0800507
Paul Crowley76107cb2016-02-09 10:04:39 +0000508static bool emulated_lock(const std::string& path) {
Jeff Sharkey7a9dd952016-01-12 16:52:16 -0700509 if (chmod(path.c_str(), 0000) != 0) {
510 PLOG(ERROR) << "Failed to chmod " << path;
Paul Crowley76107cb2016-02-09 10:04:39 +0000511 return false;
Jeff Sharkey7a9dd952016-01-12 16:52:16 -0700512 }
513#if EMULATED_USES_SELINUX
514 if (setfilecon(path.c_str(), "u:object_r:storage_stub_file:s0") != 0) {
515 PLOG(WARNING) << "Failed to setfilecon " << path;
Paul Crowley76107cb2016-02-09 10:04:39 +0000516 return false;
Jeff Sharkey7a9dd952016-01-12 16:52:16 -0700517 }
518#endif
Paul Crowley76107cb2016-02-09 10:04:39 +0000519 return true;
Jeff Sharkey7a9dd952016-01-12 16:52:16 -0700520}
521
Paul Crowley76107cb2016-02-09 10:04:39 +0000522static bool emulated_unlock(const std::string& path, mode_t mode) {
Jeff Sharkey7a9dd952016-01-12 16:52:16 -0700523 if (chmod(path.c_str(), mode) != 0) {
524 PLOG(ERROR) << "Failed to chmod " << path;
Paul Crowleya042cb52016-01-21 17:24:49 +0000525 // FIXME temporary workaround for b/26713622
Eric Biggersa701c452018-10-23 13:06:55 -0700526 if (fscrypt_is_emulated()) return false;
Jeff Sharkey7a9dd952016-01-12 16:52:16 -0700527 }
528#if EMULATED_USES_SELINUX
529 if (selinux_android_restorecon(path.c_str(), SELINUX_ANDROID_RESTORECON_FORCE) != 0) {
530 PLOG(WARNING) << "Failed to restorecon " << path;
Paul Crowleya042cb52016-01-21 17:24:49 +0000531 // FIXME temporary workaround for b/26713622
Eric Biggersa701c452018-10-23 13:06:55 -0700532 if (fscrypt_is_emulated()) return false;
Jeff Sharkey7a9dd952016-01-12 16:52:16 -0700533 }
534#endif
Paul Crowley76107cb2016-02-09 10:04:39 +0000535 return true;
Jeff Sharkey7a9dd952016-01-12 16:52:16 -0700536}
537
Paul Crowley3b71fc52017-10-09 10:55:21 -0700538static bool parse_hex(const std::string& hex, std::string* result) {
539 if (hex == "!") {
Paul Crowleya051eb72016-03-08 16:08:32 -0800540 *result = "";
Paul Crowley05720802016-02-08 15:55:41 +0000541 return true;
542 }
Paul Crowleya051eb72016-03-08 16:08:32 -0800543 if (android::vold::HexToStr(hex, *result) != 0) {
Paul Crowleydf528a72016-03-09 09:31:37 -0800544 LOG(ERROR) << "Invalid FBE hex string"; // Don't log the string for security reasons
Paul Crowley05720802016-02-08 15:55:41 +0000545 return false;
546 }
547 return true;
548}
549
Barani Muthukumaranb1927c22019-10-31 22:59:34 -0700550static std::optional<android::vold::KeyAuthentication> authentication_from_hex(
551 const std::string& token_hex, const std::string& secret_hex) {
552 std::string token, secret;
553 if (!parse_hex(token_hex, &token)) return std::optional<android::vold::KeyAuthentication>();
554 if (!parse_hex(secret_hex, &secret)) return std::optional<android::vold::KeyAuthentication>();
555 if (secret.empty()) {
556 return kEmptyAuthentication;
557 } else {
558 return android::vold::KeyAuthentication(token, secret);
559 }
560}
561
Paul Crowley3aa914d2017-10-09 16:35:51 -0700562static std::string volkey_path(const std::string& misc_path, const std::string& volume_uuid) {
563 return misc_path + "/vold/volume_keys/" + volume_uuid + "/default";
564}
565
Paul Crowley26a53882017-10-26 11:16:39 -0700566static std::string volume_secdiscardable_path(const std::string& volume_uuid) {
567 return systemwide_volume_key_dir + "/" + volume_uuid + "/secdiscardable";
568}
569
Paul Crowley3aa914d2017-10-09 16:35:51 -0700570static bool read_or_create_volkey(const std::string& misc_path, const std::string& volume_uuid,
Paul Crowley5e53ff62019-10-24 14:55:17 -0700571 EncryptionPolicy* policy) {
Paul Crowley26a53882017-10-26 11:16:39 -0700572 auto secdiscardable_path = volume_secdiscardable_path(volume_uuid);
573 std::string secdiscardable_hash;
574 if (android::vold::pathExists(secdiscardable_path)) {
575 if (!android::vold::readSecdiscardable(secdiscardable_path, &secdiscardable_hash))
576 return false;
577 } else {
578 if (fs_mkdirs(secdiscardable_path.c_str(), 0700) != 0) {
579 PLOG(ERROR) << "Creating directories for: " << secdiscardable_path;
580 return false;
581 }
582 if (!android::vold::createSecdiscardable(secdiscardable_path, &secdiscardable_hash))
583 return false;
584 }
Paul Crowley3aa914d2017-10-09 16:35:51 -0700585 auto key_path = volkey_path(misc_path, volume_uuid);
586 if (fs_mkdirs(key_path.c_str(), 0700) != 0) {
587 PLOG(ERROR) << "Creating directories for: " << key_path;
588 return false;
589 }
Paul Crowley26a53882017-10-26 11:16:39 -0700590 android::vold::KeyAuthentication auth("", secdiscardable_hash);
Eric Biggers83a73d72019-09-30 13:06:47 -0700591
Paul Crowley77df7f22020-01-23 15:29:30 -0800592 EncryptionOptions options;
593 if (!get_volume_file_encryption_options(&options)) return false;
594 KeyBuffer key;
595 if (!android::vold::retrieveKey(true, auth, key_path, key_path + "_tmp", &key)) return false;
596 if (!android::vold::installKey(BuildDataPath(volume_uuid), options, key, policy)) return false;
597 return true;
Paul Crowley3aa914d2017-10-09 16:35:51 -0700598}
599
600static bool destroy_volkey(const std::string& misc_path, const std::string& volume_uuid) {
Paul Crowleyc6433a22017-10-24 14:54:43 -0700601 auto path = volkey_path(misc_path, volume_uuid);
602 if (!android::vold::pathExists(path)) return true;
603 return android::vold::destroyKey(path);
Paul Crowley3aa914d2017-10-09 16:35:51 -0700604}
605
Barani Muthukumaranb1927c22019-10-31 22:59:34 -0700606static bool fscrypt_rewrap_user_key(userid_t user_id, int serial,
607 const android::vold::KeyAuthentication& retrieve_auth,
608 const android::vold::KeyAuthentication& store_auth) {
609 if (s_ephemeral_users.count(user_id) != 0) return true;
610 auto const directory_path = get_ce_key_directory_path(user_id);
611 KeyBuffer ce_key;
612 std::string ce_key_current_path = get_ce_key_current_path(directory_path);
613 if (android::vold::retrieveKey(ce_key_current_path, retrieve_auth, &ce_key)) {
614 LOG(DEBUG) << "Successfully retrieved key";
615 // TODO(147732812): Remove this once Locksettingservice is fixed.
616 // Currently it calls fscrypt_clear_user_key_auth with a secret when lockscreen is
617 // changed from swipe to none or vice-versa
618 } else if (android::vold::retrieveKey(ce_key_current_path, kEmptyAuthentication, &ce_key)) {
619 LOG(DEBUG) << "Successfully retrieved key with empty auth";
620 } else {
621 LOG(ERROR) << "Failed to retrieve key for user " << user_id;
622 return false;
623 }
624 auto const paths = get_ce_key_paths(directory_path);
625 std::string ce_key_path;
626 if (!get_ce_key_new_path(directory_path, paths, &ce_key_path)) return false;
627 if (!android::vold::storeKeyAtomically(ce_key_path, user_key_temp, store_auth, ce_key))
628 return false;
629 if (!android::vold::FsyncDirectory(directory_path)) return false;
630 return true;
631}
632
Eric Biggersa701c452018-10-23 13:06:55 -0700633bool fscrypt_add_user_key_auth(userid_t user_id, int serial, const std::string& token_hex,
Paul Crowley3b71fc52017-10-09 10:55:21 -0700634 const std::string& secret_hex) {
Eric Biggersa701c452018-10-23 13:06:55 -0700635 LOG(DEBUG) << "fscrypt_add_user_key_auth " << user_id << " serial=" << serial
Paul Crowley3b71fc52017-10-09 10:55:21 -0700636 << " token_present=" << (token_hex != "!");
Eric Biggersa701c452018-10-23 13:06:55 -0700637 if (!fscrypt_is_native()) return true;
Barani Muthukumaranb1927c22019-10-31 22:59:34 -0700638 auto auth = authentication_from_hex(token_hex, secret_hex);
639 if (!auth) return false;
640 return fscrypt_rewrap_user_key(user_id, serial, kEmptyAuthentication, *auth);
641}
642
643bool fscrypt_clear_user_key_auth(userid_t user_id, int serial, const std::string& token_hex,
644 const std::string& secret_hex) {
645 LOG(DEBUG) << "fscrypt_clear_user_key_auth " << user_id << " serial=" << serial
646 << " token_present=" << (token_hex != "!");
647 if (!fscrypt_is_native()) return true;
648 auto auth = authentication_from_hex(token_hex, secret_hex);
649 if (!auth) return false;
650 return fscrypt_rewrap_user_key(user_id, serial, *auth, kEmptyAuthentication);
Paul Crowleya3630362016-05-17 14:17:56 -0700651}
652
Eric Biggersa701c452018-10-23 13:06:55 -0700653bool fscrypt_fixate_newest_user_key_auth(userid_t user_id) {
654 LOG(DEBUG) << "fscrypt_fixate_newest_user_key_auth " << user_id;
655 if (!fscrypt_is_native()) return true;
Paul Crowley25a71382016-07-25 15:55:36 -0700656 if (s_ephemeral_users.count(user_id) != 0) return true;
Paul Crowleya3630362016-05-17 14:17:56 -0700657 auto const directory_path = get_ce_key_directory_path(user_id);
658 auto const paths = get_ce_key_paths(directory_path);
659 if (paths.empty()) {
660 LOG(ERROR) << "No ce keys present, cannot fixate for user " << user_id;
661 return false;
Paul Crowleyad2eb642016-02-10 17:56:05 +0000662 }
Paul Crowleya3630362016-05-17 14:17:56 -0700663 fixate_user_ce_key(directory_path, paths[0], paths);
Paul Crowley76107cb2016-02-09 10:04:39 +0000664 return true;
Paul Crowley05720802016-02-08 15:55:41 +0000665}
666
Jeff Sharkey47695b22016-02-01 17:02:29 -0700667// TODO: rename to 'install' for consistency, and take flags to know which keys to install
Eric Biggersa701c452018-10-23 13:06:55 -0700668bool fscrypt_unlock_user_key(userid_t user_id, int serial, const std::string& token_hex,
Paul Crowley3b71fc52017-10-09 10:55:21 -0700669 const std::string& secret_hex) {
Eric Biggersa701c452018-10-23 13:06:55 -0700670 LOG(DEBUG) << "fscrypt_unlock_user_key " << user_id << " serial=" << serial
Paul Crowley3b71fc52017-10-09 10:55:21 -0700671 << " token_present=" << (token_hex != "!");
Eric Biggersa701c452018-10-23 13:06:55 -0700672 if (fscrypt_is_native()) {
Paul Crowley77df7f22020-01-23 15:29:30 -0800673 if (s_ce_policies.count(user_id) != 0) {
Paul Crowley05720802016-02-08 15:55:41 +0000674 LOG(WARNING) << "Tried to unlock already-unlocked key for user " << user_id;
Paul Crowley76107cb2016-02-09 10:04:39 +0000675 return true;
Paul Crowley05720802016-02-08 15:55:41 +0000676 }
Barani Muthukumaranb1927c22019-10-31 22:59:34 -0700677 auto auth = authentication_from_hex(token_hex, secret_hex);
678 if (!auth) return false;
679 if (!read_and_install_user_ce_key(user_id, *auth)) {
Paul Crowley8fb12fd2016-02-01 14:28:12 +0000680 LOG(ERROR) << "Couldn't read key for " << user_id;
Paul Crowley76107cb2016-02-09 10:04:39 +0000681 return false;
Jeff Sharkeyd2c96e72015-11-08 17:56:23 -0800682 }
Jeff Sharkeyfc505c32015-12-07 17:27:01 -0700683 } else {
684 // When in emulation mode, we just use chmod. However, we also
685 // unlock directories when not in emulation mode, to bring devices
686 // back into a known-good state.
Paul Crowley76107cb2016-02-09 10:04:39 +0000687 if (!emulated_unlock(android::vold::BuildDataSystemCePath(user_id), 0771) ||
Paul Crowleydf528a72016-03-09 09:31:37 -0800688 !emulated_unlock(android::vold::BuildDataMiscCePath(user_id), 01771) ||
Paul Crowley3b71fc52017-10-09 10:55:21 -0700689 !emulated_unlock(android::vold::BuildDataMediaCePath("", user_id), 0770) ||
690 !emulated_unlock(android::vold::BuildDataUserCePath("", user_id), 0771)) {
Jeff Sharkey7a9dd952016-01-12 16:52:16 -0700691 LOG(ERROR) << "Failed to unlock user " << user_id;
Paul Crowley76107cb2016-02-09 10:04:39 +0000692 return false;
Jeff Sharkeyfc505c32015-12-07 17:27:01 -0700693 }
Jeff Sharkeyd2c96e72015-11-08 17:56:23 -0800694 }
Paul Crowley76107cb2016-02-09 10:04:39 +0000695 return true;
Jeff Sharkeyd2c96e72015-11-08 17:56:23 -0800696}
697
Jeff Sharkey47695b22016-02-01 17:02:29 -0700698// TODO: rename to 'evict' for consistency
Eric Biggersa701c452018-10-23 13:06:55 -0700699bool fscrypt_lock_user_key(userid_t user_id) {
700 LOG(DEBUG) << "fscrypt_lock_user_key " << user_id;
701 if (fscrypt_is_native()) {
Andrew Scull7ec25c72016-10-31 10:28:25 +0000702 return evict_ce_key(user_id);
Eric Biggersa701c452018-10-23 13:06:55 -0700703 } else if (fscrypt_is_emulated()) {
Jeff Sharkeyd2c96e72015-11-08 17:56:23 -0800704 // When in emulation mode, we just use chmod
Paul Crowley76107cb2016-02-09 10:04:39 +0000705 if (!emulated_lock(android::vold::BuildDataSystemCePath(user_id)) ||
Paul Crowleydf528a72016-03-09 09:31:37 -0800706 !emulated_lock(android::vold::BuildDataMiscCePath(user_id)) ||
Paul Crowley3b71fc52017-10-09 10:55:21 -0700707 !emulated_lock(android::vold::BuildDataMediaCePath("", user_id)) ||
708 !emulated_lock(android::vold::BuildDataUserCePath("", user_id))) {
Paul Crowley57eedbf2016-02-09 09:30:23 +0000709 LOG(ERROR) << "Failed to lock user " << user_id;
Paul Crowley76107cb2016-02-09 10:04:39 +0000710 return false;
Jeff Sharkeyd2c96e72015-11-08 17:56:23 -0800711 }
Jeff Sharkeyd2c96e72015-11-08 17:56:23 -0800712 }
Jeff Sharkeyfc505c32015-12-07 17:27:01 -0700713
Paul Crowley76107cb2016-02-09 10:04:39 +0000714 return true;
Jeff Sharkeyd2c96e72015-11-08 17:56:23 -0800715}
716
Paul Crowley82b41ff2017-10-20 08:17:54 -0700717static bool prepare_subdirs(const std::string& action, const std::string& volume_uuid,
718 userid_t user_id, int flags) {
719 if (0 != android::vold::ForkExecvp(
720 std::vector<std::string>{prepare_subdirs_path, action, volume_uuid,
721 std::to_string(user_id), std::to_string(flags)})) {
722 LOG(ERROR) << "vold_prepare_subdirs failed";
Paul Crowley8e550662017-10-16 17:01:44 -0700723 return false;
724 }
725 return true;
726}
727
Eric Biggersa701c452018-10-23 13:06:55 -0700728bool fscrypt_prepare_user_storage(const std::string& volume_uuid, userid_t user_id, int serial,
Paul Crowley3b71fc52017-10-09 10:55:21 -0700729 int flags) {
Eric Biggersa701c452018-10-23 13:06:55 -0700730 LOG(DEBUG) << "fscrypt_prepare_user_storage for volume " << escape_empty(volume_uuid)
Paul Crowleydf528a72016-03-09 09:31:37 -0800731 << ", user " << user_id << ", serial " << serial << ", flags " << flags;
Jeff Sharkey47695b22016-02-01 17:02:29 -0700732
Paul Crowley82b41ff2017-10-20 08:17:54 -0700733 if (flags & android::os::IVold::STORAGE_FLAG_DE) {
Jeff Sharkeybe70c9a2016-04-14 20:45:16 -0600734 // DE_sys key
735 auto system_legacy_path = android::vold::BuildDataSystemLegacyPath(user_id);
736 auto misc_legacy_path = android::vold::BuildDataMiscLegacyPath(user_id);
737 auto profiles_de_path = android::vold::BuildDataProfilesDePath(user_id);
Jeff Sharkeybe70c9a2016-04-14 20:45:16 -0600738
739 // DE_n key
Jeff Sharkey47695b22016-02-01 17:02:29 -0700740 auto system_de_path = android::vold::BuildDataSystemDePath(user_id);
741 auto misc_de_path = android::vold::BuildDataMiscDePath(user_id);
Andreas Huber71cd43f2018-01-22 11:25:29 -0800742 auto vendor_de_path = android::vold::BuildDataVendorDePath(user_id);
Jeff Sharkey47695b22016-02-01 17:02:29 -0700743 auto user_de_path = android::vold::BuildDataUserDePath(volume_uuid, user_id);
744
Paul Crowley3b71fc52017-10-09 10:55:21 -0700745 if (volume_uuid.empty()) {
Paul Crowley6b756ce2017-10-05 14:07:09 -0700746 if (!prepare_dir(system_legacy_path, 0700, AID_SYSTEM, AID_SYSTEM)) return false;
Jeff Sharkeybe70c9a2016-04-14 20:45:16 -0600747#if MANAGE_MISC_DIRS
Paul Crowley6b756ce2017-10-05 14:07:09 -0700748 if (!prepare_dir(misc_legacy_path, 0750, multiuser_get_uid(user_id, AID_SYSTEM),
Paul Crowley14c8c072018-09-18 13:30:21 -0700749 multiuser_get_uid(user_id, AID_EVERYBODY)))
750 return false;
Jeff Sharkeybe70c9a2016-04-14 20:45:16 -0600751#endif
Paul Crowley6b756ce2017-10-05 14:07:09 -0700752 if (!prepare_dir(profiles_de_path, 0771, AID_SYSTEM, AID_SYSTEM)) return false;
Jeff Sharkeybe70c9a2016-04-14 20:45:16 -0600753
Paul Crowley6b756ce2017-10-05 14:07:09 -0700754 if (!prepare_dir(system_de_path, 0770, AID_SYSTEM, AID_SYSTEM)) return false;
755 if (!prepare_dir(misc_de_path, 01771, AID_SYSTEM, AID_MISC)) return false;
Andreas Huber71cd43f2018-01-22 11:25:29 -0800756 if (!prepare_dir(vendor_de_path, 0771, AID_ROOT, AID_ROOT)) return false;
Paul Crowley6b756ce2017-10-05 14:07:09 -0700757 }
Paul Crowley76107cb2016-02-09 10:04:39 +0000758 if (!prepare_dir(user_de_path, 0771, AID_SYSTEM, AID_SYSTEM)) return false;
Calin Juravled1ee9442016-03-02 18:36:50 +0000759
Eric Biggersa701c452018-10-23 13:06:55 -0700760 if (fscrypt_is_native()) {
Paul Crowley5e53ff62019-10-24 14:55:17 -0700761 EncryptionPolicy de_policy;
Paul Crowley3b71fc52017-10-09 10:55:21 -0700762 if (volume_uuid.empty()) {
Paul Crowley77df7f22020-01-23 15:29:30 -0800763 if (!lookup_policy(s_de_policies, user_id, &de_policy)) return false;
Paul Crowley5e53ff62019-10-24 14:55:17 -0700764 if (!EnsurePolicy(de_policy, system_de_path)) return false;
765 if (!EnsurePolicy(de_policy, misc_de_path)) return false;
766 if (!EnsurePolicy(de_policy, vendor_de_path)) return false;
Paul Crowley3aa914d2017-10-09 16:35:51 -0700767 } else {
Paul Crowley5e53ff62019-10-24 14:55:17 -0700768 if (!read_or_create_volkey(misc_de_path, volume_uuid, &de_policy)) return false;
Paul Crowley6b756ce2017-10-05 14:07:09 -0700769 }
Paul Crowley5e53ff62019-10-24 14:55:17 -0700770 if (!EnsurePolicy(de_policy, user_de_path)) return false;
Jeff Sharkey47695b22016-02-01 17:02:29 -0700771 }
Paul Crowley285956f2016-01-20 13:12:38 +0000772 }
Jeff Sharkeyd2c96e72015-11-08 17:56:23 -0800773
Paul Crowley82b41ff2017-10-20 08:17:54 -0700774 if (flags & android::os::IVold::STORAGE_FLAG_CE) {
Jeff Sharkeybe70c9a2016-04-14 20:45:16 -0600775 // CE_n key
Jeff Sharkey47695b22016-02-01 17:02:29 -0700776 auto system_ce_path = android::vold::BuildDataSystemCePath(user_id);
777 auto misc_ce_path = android::vold::BuildDataMiscCePath(user_id);
Andreas Huber71cd43f2018-01-22 11:25:29 -0800778 auto vendor_ce_path = android::vold::BuildDataVendorCePath(user_id);
Jeff Sharkeybe70c9a2016-04-14 20:45:16 -0600779 auto media_ce_path = android::vold::BuildDataMediaCePath(volume_uuid, user_id);
780 auto user_ce_path = android::vold::BuildDataUserCePath(volume_uuid, user_id);
Jeff Sharkeyd2c96e72015-11-08 17:56:23 -0800781
Paul Crowley3b71fc52017-10-09 10:55:21 -0700782 if (volume_uuid.empty()) {
Paul Crowley6b756ce2017-10-05 14:07:09 -0700783 if (!prepare_dir(system_ce_path, 0770, AID_SYSTEM, AID_SYSTEM)) return false;
784 if (!prepare_dir(misc_ce_path, 01771, AID_SYSTEM, AID_MISC)) return false;
Andreas Huber71cd43f2018-01-22 11:25:29 -0800785 if (!prepare_dir(vendor_ce_path, 0771, AID_ROOT, AID_ROOT)) return false;
Paul Crowley6b756ce2017-10-05 14:07:09 -0700786 }
Paul Crowley76107cb2016-02-09 10:04:39 +0000787 if (!prepare_dir(media_ce_path, 0770, AID_MEDIA_RW, AID_MEDIA_RW)) return false;
788 if (!prepare_dir(user_ce_path, 0771, AID_SYSTEM, AID_SYSTEM)) return false;
Jeff Sharkey47695b22016-02-01 17:02:29 -0700789
Eric Biggersa701c452018-10-23 13:06:55 -0700790 if (fscrypt_is_native()) {
Paul Crowley5e53ff62019-10-24 14:55:17 -0700791 EncryptionPolicy ce_policy;
Paul Crowley3b71fc52017-10-09 10:55:21 -0700792 if (volume_uuid.empty()) {
Paul Crowley77df7f22020-01-23 15:29:30 -0800793 if (!lookup_policy(s_ce_policies, user_id, &ce_policy)) return false;
Paul Crowley5e53ff62019-10-24 14:55:17 -0700794 if (!EnsurePolicy(ce_policy, system_ce_path)) return false;
795 if (!EnsurePolicy(ce_policy, misc_ce_path)) return false;
796 if (!EnsurePolicy(ce_policy, vendor_ce_path)) return false;
Paul Crowley3aa914d2017-10-09 16:35:51 -0700797 } else {
Paul Crowley5e53ff62019-10-24 14:55:17 -0700798 if (!read_or_create_volkey(misc_ce_path, volume_uuid, &ce_policy)) return false;
Paul Crowley6b756ce2017-10-05 14:07:09 -0700799 }
Paul Crowley5e53ff62019-10-24 14:55:17 -0700800 if (!EnsurePolicy(ce_policy, media_ce_path)) return false;
801 if (!EnsurePolicy(ce_policy, user_ce_path)) return false;
Jeff Sharkey47695b22016-02-01 17:02:29 -0700802 }
Paul Crowley1a965262017-10-13 13:49:50 -0700803
804 if (volume_uuid.empty()) {
Paul Crowley8e550662017-10-16 17:01:44 -0700805 // Now that credentials have been installed, we can run restorecon
806 // over these paths
807 // NOTE: these paths need to be kept in sync with libselinux
808 android::vold::RestoreconRecursive(system_ce_path);
Nick Kralevich6a3ef482019-05-14 09:30:29 -0700809 android::vold::RestoreconRecursive(vendor_ce_path);
Paul Crowley8e550662017-10-16 17:01:44 -0700810 android::vold::RestoreconRecursive(misc_ce_path);
Paul Crowley1a965262017-10-13 13:49:50 -0700811 }
Jeff Sharkeyd2c96e72015-11-08 17:56:23 -0800812 }
Paul Crowley82b41ff2017-10-20 08:17:54 -0700813 if (!prepare_subdirs("prepare", volume_uuid, user_id, flags)) return false;
Jeff Sharkeyd2c96e72015-11-08 17:56:23 -0800814
Paul Crowley76107cb2016-02-09 10:04:39 +0000815 return true;
Jeff Sharkeyd2c96e72015-11-08 17:56:23 -0800816}
Jeff Sharkeybe70c9a2016-04-14 20:45:16 -0600817
Eric Biggersa701c452018-10-23 13:06:55 -0700818bool fscrypt_destroy_user_storage(const std::string& volume_uuid, userid_t user_id, int flags) {
819 LOG(DEBUG) << "fscrypt_destroy_user_storage for volume " << escape_empty(volume_uuid)
Jeff Sharkeybe70c9a2016-04-14 20:45:16 -0600820 << ", user " << user_id << ", flags " << flags;
821 bool res = true;
822
Paul Crowley82b41ff2017-10-20 08:17:54 -0700823 res &= prepare_subdirs("destroy", volume_uuid, user_id, flags);
824
825 if (flags & android::os::IVold::STORAGE_FLAG_CE) {
Paul Crowley8e550662017-10-16 17:01:44 -0700826 // CE_n key
827 auto system_ce_path = android::vold::BuildDataSystemCePath(user_id);
828 auto misc_ce_path = android::vold::BuildDataMiscCePath(user_id);
Andreas Huber71cd43f2018-01-22 11:25:29 -0800829 auto vendor_ce_path = android::vold::BuildDataVendorCePath(user_id);
Paul Crowley8e550662017-10-16 17:01:44 -0700830 auto media_ce_path = android::vold::BuildDataMediaCePath(volume_uuid, user_id);
831 auto user_ce_path = android::vold::BuildDataUserCePath(volume_uuid, user_id);
832
833 res &= destroy_dir(media_ce_path);
834 res &= destroy_dir(user_ce_path);
835 if (volume_uuid.empty()) {
Paul Crowley8e550662017-10-16 17:01:44 -0700836 res &= destroy_dir(system_ce_path);
837 res &= destroy_dir(misc_ce_path);
Andreas Huber71cd43f2018-01-22 11:25:29 -0800838 res &= destroy_dir(vendor_ce_path);
Paul Crowley3aa914d2017-10-09 16:35:51 -0700839 } else {
Eric Biggersa701c452018-10-23 13:06:55 -0700840 if (fscrypt_is_native()) {
Paul Crowley3aa914d2017-10-09 16:35:51 -0700841 res &= destroy_volkey(misc_ce_path, volume_uuid);
842 }
Paul Crowley8e550662017-10-16 17:01:44 -0700843 }
844 }
845
Paul Crowley82b41ff2017-10-20 08:17:54 -0700846 if (flags & android::os::IVold::STORAGE_FLAG_DE) {
Jeff Sharkeybe70c9a2016-04-14 20:45:16 -0600847 // DE_sys key
848 auto system_legacy_path = android::vold::BuildDataSystemLegacyPath(user_id);
849 auto misc_legacy_path = android::vold::BuildDataMiscLegacyPath(user_id);
850 auto profiles_de_path = android::vold::BuildDataProfilesDePath(user_id);
Jeff Sharkeybe70c9a2016-04-14 20:45:16 -0600851
852 // DE_n key
853 auto system_de_path = android::vold::BuildDataSystemDePath(user_id);
854 auto misc_de_path = android::vold::BuildDataMiscDePath(user_id);
Andreas Huber71cd43f2018-01-22 11:25:29 -0800855 auto vendor_de_path = android::vold::BuildDataVendorDePath(user_id);
Jeff Sharkeybe70c9a2016-04-14 20:45:16 -0600856 auto user_de_path = android::vold::BuildDataUserDePath(volume_uuid, user_id);
857
Paul Crowley8e550662017-10-16 17:01:44 -0700858 res &= destroy_dir(user_de_path);
Paul Crowley3b71fc52017-10-09 10:55:21 -0700859 if (volume_uuid.empty()) {
Jeff Sharkeybe70c9a2016-04-14 20:45:16 -0600860 res &= destroy_dir(system_legacy_path);
861#if MANAGE_MISC_DIRS
862 res &= destroy_dir(misc_legacy_path);
863#endif
864 res &= destroy_dir(profiles_de_path);
Jeff Sharkeybe70c9a2016-04-14 20:45:16 -0600865 res &= destroy_dir(system_de_path);
866 res &= destroy_dir(misc_de_path);
Andreas Huber71cd43f2018-01-22 11:25:29 -0800867 res &= destroy_dir(vendor_de_path);
Paul Crowley3aa914d2017-10-09 16:35:51 -0700868 } else {
Eric Biggersa701c452018-10-23 13:06:55 -0700869 if (fscrypt_is_native()) {
Paul Crowley3aa914d2017-10-09 16:35:51 -0700870 res &= destroy_volkey(misc_de_path, volume_uuid);
871 }
Jeff Sharkeybe70c9a2016-04-14 20:45:16 -0600872 }
Jeff Sharkeybe70c9a2016-04-14 20:45:16 -0600873 }
874
875 return res;
876}
Rubin Xu2436e272017-04-27 20:43:10 +0100877
Paul Crowleyc6433a22017-10-24 14:54:43 -0700878static bool destroy_volume_keys(const std::string& directory_path, const std::string& volume_uuid) {
879 auto dirp = std::unique_ptr<DIR, int (*)(DIR*)>(opendir(directory_path.c_str()), closedir);
880 if (!dirp) {
881 PLOG(ERROR) << "Unable to open directory: " + directory_path;
882 return false;
883 }
884 bool res = true;
885 for (;;) {
886 errno = 0;
887 auto const entry = readdir(dirp.get());
888 if (!entry) {
889 if (errno) {
890 PLOG(ERROR) << "Unable to read directory: " + directory_path;
891 return false;
892 }
893 break;
894 }
895 if (entry->d_type != DT_DIR || entry->d_name[0] == '.') {
896 LOG(DEBUG) << "Skipping non-user " << entry->d_name;
897 continue;
898 }
899 res &= destroy_volkey(directory_path + "/" + entry->d_name, volume_uuid);
900 }
901 return res;
902}
903
Eric Biggersa701c452018-10-23 13:06:55 -0700904bool fscrypt_destroy_volume_keys(const std::string& volume_uuid) {
Paul Crowleyc6433a22017-10-24 14:54:43 -0700905 bool res = true;
Eric Biggersa701c452018-10-23 13:06:55 -0700906 LOG(DEBUG) << "fscrypt_destroy_volume_keys for volume " << escape_empty(volume_uuid);
Paul Crowley26a53882017-10-26 11:16:39 -0700907 auto secdiscardable_path = volume_secdiscardable_path(volume_uuid);
908 res &= android::vold::runSecdiscardSingle(secdiscardable_path);
Paul Crowleyc6433a22017-10-24 14:54:43 -0700909 res &= destroy_volume_keys("/data/misc_ce", volume_uuid);
910 res &= destroy_volume_keys("/data/misc_de", volume_uuid);
911 return res;
912}