2 * Copyright (C) 2016 The Android Open Source Project
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
8 * http://www.apache.org/licenses/LICENSE-2.0
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.
17 #include "KeyStorage.h"
19 #include "Checkpoint.h"
20 #include "Keymaster.h"
21 #include "ScryptParameters.h"
33 #include <sys/types.h>
37 #include <openssl/err.h>
38 #include <openssl/evp.h>
39 #include <openssl/sha.h>
41 #include <android-base/file.h>
42 #include <android-base/logging.h>
43 #include <android-base/properties.h>
44 #include <android-base/unique_fd.h>
46 #include <cutils/properties.h>
50 #include "crypto_scrypt.h"
56 const KeyAuthentication kEmptyAuthentication{""};
58 static constexpr size_t AES_KEY_BYTES = 32;
59 static constexpr size_t GCM_NONCE_BYTES = 12;
60 static constexpr size_t GCM_MAC_BYTES = 16;
61 static constexpr size_t SECDISCARDABLE_BYTES = 1 << 14;
63 static const char* kCurrentVersion = "1";
64 static const char* kRmPath = "/system/bin/rm";
65 static const char* kSecdiscardPath = "/system/bin/secdiscard";
66 static const char* kStretch_none = "none";
67 static const char* kStretch_nopassword = "nopassword";
68 static const char* kHashPrefix_secdiscardable = "Android secdiscardable SHA512";
69 static const char* kHashPrefix_keygen = "Android key wrapping key generation SHA512";
70 static const char* kFn_encrypted_key = "encrypted_key";
71 static const char* kFn_keymaster_key_blob = "keymaster_key_blob";
72 static const char* kFn_keymaster_key_blob_upgraded = "keymaster_key_blob_upgraded";
73 static const char* kFn_secdiscardable = "secdiscardable";
74 static const char* kFn_stretching = "stretching";
75 static const char* kFn_version = "version";
79 // Storage binding info for ensuring key encryption keys include a
80 // platform-provided seed in their derivation.
81 struct StorageBindingInfo {
84 IN_USE, // key storage keys are bound to seed
85 NOT_USED, // key storage keys are NOT bound to seed
88 // Binding seed mixed into all key storage keys.
89 std::vector<uint8_t> seed;
91 // State tracker for the key storage key binding.
92 State state = State::UNINITIALIZED;
97 // Never freed as the dtor is non-trivial.
98 StorageBindingInfo& storage_binding_info = *new StorageBindingInfo;
102 static bool checkSize(const std::string& kind, size_t actual, size_t expected) {
103 if (actual != expected) {
104 LOG(ERROR) << "Wrong number of bytes in " << kind << ", expected " << expected << " got "
111 static void hashWithPrefix(char const* prefix, const std::string& tohash, std::string* res) {
115 // Personalise the hashing by introducing a fixed prefix.
116 // Hashing applications should use personalization except when there is a
117 // specific reason not to; see section 4.11 of https://www.schneier.com/skein1.3.pdf
118 std::string hashingPrefix = prefix;
119 hashingPrefix.resize(SHA512_CBLOCK);
120 SHA512_Update(&c, hashingPrefix.data(), hashingPrefix.size());
121 SHA512_Update(&c, tohash.data(), tohash.size());
122 res->assign(SHA512_DIGEST_LENGTH, '\0');
123 SHA512_Final(reinterpret_cast<uint8_t*>(&(*res)[0]), &c);
126 // Generates a keymaster key, using rollback resistance if supported.
127 static bool generateKeymasterKey(Keymaster& keymaster,
128 const km::AuthorizationSetBuilder& paramBuilder,
130 auto paramsWithRollback = paramBuilder;
131 paramsWithRollback.Authorization(km::TAG_ROLLBACK_RESISTANCE);
133 if (!keymaster.generateKey(paramsWithRollback, key)) {
134 LOG(WARNING) << "Failed to generate rollback-resistant key. This is expected if keymaster "
135 "doesn't support rollback resistance. Falling back to "
136 "non-rollback-resistant key.";
137 if (!keymaster.generateKey(paramBuilder, key)) return false;
142 static bool generateKeyStorageKey(Keymaster& keymaster, const std::string& appId,
144 auto paramBuilder = km::AuthorizationSetBuilder()
145 .AesEncryptionKey(AES_KEY_BYTES * 8)
146 .GcmModeMinMacLen(GCM_MAC_BYTES * 8)
147 .Authorization(km::TAG_APPLICATION_ID, appId)
148 .Authorization(km::TAG_NO_AUTH_REQUIRED);
149 LOG(DEBUG) << "Generating \"key storage\" key";
150 return generateKeymasterKey(keymaster, paramBuilder, key);
153 bool generateWrappedStorageKey(KeyBuffer* key) {
155 if (!keymaster) return false;
156 std::string key_temp;
157 auto paramBuilder = km::AuthorizationSetBuilder().AesEncryptionKey(AES_KEY_BYTES * 8);
158 paramBuilder.Authorization(km::TAG_STORAGE_KEY);
159 if (!generateKeymasterKey(keymaster, paramBuilder, &key_temp)) return false;
160 *key = KeyBuffer(key_temp.size());
161 memcpy(reinterpret_cast<void*>(key->data()), key_temp.c_str(), key->size());
165 bool exportWrappedStorageKey(const KeyBuffer& kmKey, KeyBuffer* key) {
167 if (!keymaster) return false;
168 std::string key_temp;
170 if (!keymaster.exportKey(kmKey, &key_temp)) return false;
171 *key = KeyBuffer(key_temp.size());
172 memcpy(reinterpret_cast<void*>(key->data()), key_temp.c_str(), key->size());
176 static km::AuthorizationSet beginParams(const std::string& appId) {
177 return km::AuthorizationSetBuilder()
178 .GcmModeMacLen(GCM_MAC_BYTES * 8)
179 .Authorization(km::TAG_APPLICATION_ID, appId);
182 static bool readFileToString(const std::string& filename, std::string* result) {
183 if (!android::base::ReadFileToString(filename, result)) {
184 PLOG(ERROR) << "Failed to read from " << filename;
190 static bool readRandomBytesOrLog(size_t count, std::string* out) {
191 auto status = ReadRandomBytes(count, *out);
193 LOG(ERROR) << "Random read failed with status: " << status;
199 bool createSecdiscardable(const std::string& filename, std::string* hash) {
200 std::string secdiscardable;
201 if (!readRandomBytesOrLog(SECDISCARDABLE_BYTES, &secdiscardable)) return false;
202 if (!writeStringToFile(secdiscardable, filename)) return false;
203 hashWithPrefix(kHashPrefix_secdiscardable, secdiscardable, hash);
207 bool readSecdiscardable(const std::string& filename, std::string* hash) {
208 std::string secdiscardable;
209 if (!readFileToString(filename, &secdiscardable)) return false;
210 hashWithPrefix(kHashPrefix_secdiscardable, secdiscardable, hash);
214 static std::mutex key_upgrade_lock;
216 // List of key directories that have had their Keymaster key upgraded during
217 // this boot and written to "keymaster_key_blob_upgraded", but replacing the old
218 // key was delayed due to an active checkpoint. Protected by key_upgrade_lock.
219 static std::vector<std::string> key_dirs_to_commit;
221 // Replaces |dir|/keymaster_key_blob with |dir|/keymaster_key_blob_upgraded and
222 // deletes the old key from Keymaster.
223 static bool CommitUpgradedKey(Keymaster& keymaster, const std::string& dir) {
224 auto blob_file = dir + "/" + kFn_keymaster_key_blob;
225 auto upgraded_blob_file = dir + "/" + kFn_keymaster_key_blob_upgraded;
228 if (!readFileToString(blob_file, &blob)) return false;
230 if (rename(upgraded_blob_file.c_str(), blob_file.c_str()) != 0) {
231 PLOG(ERROR) << "Failed to rename " << upgraded_blob_file << " to " << blob_file;
234 // Ensure that the rename is persisted before deleting the Keymaster key.
235 if (!FsyncDirectory(dir)) return false;
237 if (!keymaster || !keymaster.deleteKey(blob)) {
238 LOG(WARNING) << "Failed to delete old key " << blob_file
239 << " from Keymaster; continuing anyway";
240 // Continue on, but the space in Keymaster used by the old key won't be freed.
245 static void DeferredCommitKeys() {
246 android::base::WaitForProperty("vold.checkpoint_committed", "1");
247 LOG(INFO) << "Committing upgraded keys";
250 LOG(ERROR) << "Failed to open Keymaster; old keys won't be deleted from Keymaster";
251 // Continue on, but the space in Keymaster used by the old keys won't be freed.
253 std::lock_guard<std::mutex> lock(key_upgrade_lock);
254 for (auto& dir : key_dirs_to_commit) {
255 LOG(INFO) << "Committing upgraded key " << dir;
256 CommitUpgradedKey(keymaster, dir);
258 key_dirs_to_commit.clear();
261 // Returns true if the Keymaster key in |dir| has already been upgraded and is
262 // pending being committed. Assumes that key_upgrade_lock is held.
263 static bool IsKeyCommitPending(const std::string& dir) {
264 for (const auto& dir_to_commit : key_dirs_to_commit) {
265 if (IsSameFile(dir, dir_to_commit)) return true;
270 // Schedules the upgraded Keymaster key in |dir| to be committed later.
271 // Assumes that key_upgrade_lock is held.
272 static void ScheduleKeyCommit(const std::string& dir) {
273 if (key_dirs_to_commit.empty()) std::thread(DeferredCommitKeys).detach();
274 key_dirs_to_commit.push_back(dir);
277 static void CancelPendingKeyCommit(const std::string& dir) {
278 std::lock_guard<std::mutex> lock(key_upgrade_lock);
279 for (auto it = key_dirs_to_commit.begin(); it != key_dirs_to_commit.end(); it++) {
280 if (IsSameFile(*it, dir)) {
281 LOG(DEBUG) << "Cancelling pending commit of upgraded key " << dir
282 << " because it is being destroyed";
283 key_dirs_to_commit.erase(it);
289 // Renames a key directory. Also updates the deferred commit vector
290 // (key_dirs_to_commit) appropriately.
292 // However, @old_name must be the path to the directory that was used to put that
293 // directory into the deferred commit list in the first place (since this function
294 // directly compares paths instead of using IsSameFile()).
295 static bool RenameKeyDir(const std::string& old_name, const std::string& new_name) {
296 std::lock_guard<std::mutex> lock(key_upgrade_lock);
298 if (rename(old_name.c_str(), new_name.c_str()) != 0) return false;
300 // IsSameFile() doesn't work here since we just renamed @old_name.
301 for (auto it = key_dirs_to_commit.begin(); it != key_dirs_to_commit.end(); it++) {
302 if (*it == old_name) *it = new_name;
307 // Deletes a leftover upgraded key, if present. An upgraded key can be left
308 // over if an update failed, or if we rebooted before committing the key in a
309 // freak accident. Either way, we can re-upgrade the key if we need to.
310 static void DeleteUpgradedKey(Keymaster& keymaster, const std::string& path) {
311 if (pathExists(path)) {
312 LOG(DEBUG) << "Deleting leftover upgraded key " << path;
314 if (!android::base::ReadFileToString(path, &blob)) {
315 LOG(WARNING) << "Failed to read leftover upgraded key " << path
316 << "; continuing anyway";
317 } else if (!keymaster.deleteKey(blob)) {
318 LOG(WARNING) << "Failed to delete leftover upgraded key " << path
319 << " from Keymaster; continuing anyway";
321 if (unlink(path.c_str()) != 0) {
322 LOG(WARNING) << "Failed to unlink leftover upgraded key " << path
323 << "; continuing anyway";
328 // Begins a Keymaster operation using the key stored in |dir|.
329 static KeymasterOperation BeginKeymasterOp(Keymaster& keymaster, const std::string& dir,
330 const km::AuthorizationSet& keyParams,
331 const km::AuthorizationSet& opParams,
332 km::AuthorizationSet* outParams) {
333 km::AuthorizationSet inParams(keyParams);
334 inParams.append(opParams.begin(), opParams.end());
336 auto blob_file = dir + "/" + kFn_keymaster_key_blob;
337 auto upgraded_blob_file = dir + "/" + kFn_keymaster_key_blob_upgraded;
339 std::lock_guard<std::mutex> lock(key_upgrade_lock);
342 bool already_upgraded = IsKeyCommitPending(dir);
343 if (already_upgraded) {
346 << " was already upgraded and is waiting to be committed; using the upgraded blob";
347 if (!readFileToString(upgraded_blob_file, &blob)) return KeymasterOperation();
349 DeleteUpgradedKey(keymaster, upgraded_blob_file);
350 if (!readFileToString(blob_file, &blob)) return KeymasterOperation();
353 auto opHandle = keymaster.begin(blob, inParams, outParams);
354 if (!opHandle) return opHandle;
356 // If key blob wasn't upgraded, nothing left to do.
357 if (!opHandle.getUpgradedBlob()) return opHandle;
359 if (already_upgraded) {
360 LOG(ERROR) << "Unexpected case; already-upgraded key " << upgraded_blob_file
361 << " still requires upgrade";
362 return KeymasterOperation();
364 LOG(INFO) << "Upgrading key: " << blob_file;
365 if (!writeStringToFile(*opHandle.getUpgradedBlob(), upgraded_blob_file))
366 return KeymasterOperation();
367 if (cp_needsCheckpoint()) {
368 LOG(INFO) << "Wrote upgraded key to " << upgraded_blob_file
369 << "; delaying commit due to checkpoint";
370 ScheduleKeyCommit(dir);
372 if (!CommitUpgradedKey(keymaster, dir)) return KeymasterOperation();
373 LOG(INFO) << "Key upgraded: " << blob_file;
378 static bool encryptWithKeymasterKey(Keymaster& keymaster, const std::string& dir,
379 const km::AuthorizationSet& keyParams,
380 const KeyBuffer& message, std::string* ciphertext) {
381 km::AuthorizationSet opParams =
382 km::AuthorizationSetBuilder().Authorization(km::TAG_PURPOSE, km::KeyPurpose::ENCRYPT);
383 km::AuthorizationSet outParams;
384 auto opHandle = BeginKeymasterOp(keymaster, dir, keyParams, opParams, &outParams);
385 if (!opHandle) return false;
386 auto nonceBlob = outParams.GetTagValue(km::TAG_NONCE);
388 LOG(ERROR) << "GCM encryption but no nonce generated";
391 // nonceBlob here is just a pointer into existing data, must not be freed
392 std::string nonce(nonceBlob.value().get().begin(), nonceBlob.value().get().end());
393 if (!checkSize("nonce", nonce.size(), GCM_NONCE_BYTES)) return false;
395 if (!opHandle.updateCompletely(message, &body)) return false;
398 if (!opHandle.finish(&mac)) return false;
399 if (!checkSize("mac", mac.size(), GCM_MAC_BYTES)) return false;
400 *ciphertext = nonce + body + mac;
404 static bool decryptWithKeymasterKey(Keymaster& keymaster, const std::string& dir,
405 const km::AuthorizationSet& keyParams,
406 const std::string& ciphertext, KeyBuffer* message) {
407 const std::string nonce = ciphertext.substr(0, GCM_NONCE_BYTES);
408 auto bodyAndMac = ciphertext.substr(GCM_NONCE_BYTES);
409 auto opParams = km::AuthorizationSetBuilder()
410 .Authorization(km::TAG_NONCE, nonce)
411 .Authorization(km::TAG_PURPOSE, km::KeyPurpose::DECRYPT);
412 auto opHandle = BeginKeymasterOp(keymaster, dir, keyParams, opParams, nullptr);
413 if (!opHandle) return false;
414 if (!opHandle.updateCompletely(bodyAndMac, message)) return false;
415 if (!opHandle.finish(nullptr)) return false;
419 static std::string getStretching(const KeyAuthentication& auth) {
420 if (auth.usesKeymaster()) {
421 return kStretch_nopassword;
423 return kStretch_none;
427 static bool stretchSecret(const std::string& stretching, const std::string& secret,
428 std::string* stretched) {
429 if (stretching == kStretch_nopassword) {
430 if (!secret.empty()) {
431 LOG(WARNING) << "Password present but stretching is nopassword";
435 } else if (stretching == kStretch_none) {
438 LOG(ERROR) << "Unknown stretching type: " << stretching;
444 static bool generateAppId(const KeyAuthentication& auth, const std::string& stretching,
445 const std::string& secdiscardable_hash, std::string* appId) {
446 std::string stretched;
447 if (!stretchSecret(stretching, auth.secret, &stretched)) return false;
448 *appId = secdiscardable_hash + stretched;
450 const std::lock_guard<std::mutex> scope_lock(storage_binding_info.guard);
451 switch (storage_binding_info.state) {
452 case StorageBindingInfo::State::UNINITIALIZED:
453 storage_binding_info.state = StorageBindingInfo::State::NOT_USED;
455 case StorageBindingInfo::State::IN_USE:
456 appId->append(storage_binding_info.seed.begin(), storage_binding_info.seed.end());
458 case StorageBindingInfo::State::NOT_USED:
466 static void logOpensslError() {
467 LOG(ERROR) << "Openssl error: " << ERR_get_error();
470 static bool encryptWithoutKeymaster(const std::string& preKey, const KeyBuffer& plaintext,
471 std::string* ciphertext) {
473 hashWithPrefix(kHashPrefix_keygen, preKey, &key);
474 key.resize(AES_KEY_BYTES);
475 if (!readRandomBytesOrLog(GCM_NONCE_BYTES, ciphertext)) return false;
476 auto ctx = std::unique_ptr<EVP_CIPHER_CTX, decltype(&::EVP_CIPHER_CTX_free)>(
477 EVP_CIPHER_CTX_new(), EVP_CIPHER_CTX_free);
482 if (1 != EVP_EncryptInit_ex(ctx.get(), EVP_aes_256_gcm(), NULL,
483 reinterpret_cast<const uint8_t*>(key.data()),
484 reinterpret_cast<const uint8_t*>(ciphertext->data()))) {
488 ciphertext->resize(GCM_NONCE_BYTES + plaintext.size() + GCM_MAC_BYTES);
490 if (1 != EVP_EncryptUpdate(
491 ctx.get(), reinterpret_cast<uint8_t*>(&(*ciphertext)[0] + GCM_NONCE_BYTES),
492 &outlen, reinterpret_cast<const uint8_t*>(plaintext.data()), plaintext.size())) {
496 if (outlen != static_cast<int>(plaintext.size())) {
497 LOG(ERROR) << "GCM ciphertext length should be " << plaintext.size() << " was " << outlen;
500 if (1 != EVP_EncryptFinal_ex(
502 reinterpret_cast<uint8_t*>(&(*ciphertext)[0] + GCM_NONCE_BYTES + plaintext.size()),
508 LOG(ERROR) << "GCM EncryptFinal should be 0, was " << outlen;
511 if (1 != EVP_CIPHER_CTX_ctrl(ctx.get(), EVP_CTRL_GCM_GET_TAG, GCM_MAC_BYTES,
512 reinterpret_cast<uint8_t*>(&(*ciphertext)[0] + GCM_NONCE_BYTES +
513 plaintext.size()))) {
520 static bool decryptWithoutKeymaster(const std::string& preKey, const std::string& ciphertext,
521 KeyBuffer* plaintext) {
522 if (ciphertext.size() < GCM_NONCE_BYTES + GCM_MAC_BYTES) {
523 LOG(ERROR) << "GCM ciphertext too small: " << ciphertext.size();
527 hashWithPrefix(kHashPrefix_keygen, preKey, &key);
528 key.resize(AES_KEY_BYTES);
529 auto ctx = std::unique_ptr<EVP_CIPHER_CTX, decltype(&::EVP_CIPHER_CTX_free)>(
530 EVP_CIPHER_CTX_new(), EVP_CIPHER_CTX_free);
535 if (1 != EVP_DecryptInit_ex(ctx.get(), EVP_aes_256_gcm(), NULL,
536 reinterpret_cast<const uint8_t*>(key.data()),
537 reinterpret_cast<const uint8_t*>(ciphertext.data()))) {
541 *plaintext = KeyBuffer(ciphertext.size() - GCM_NONCE_BYTES - GCM_MAC_BYTES);
543 if (1 != EVP_DecryptUpdate(ctx.get(), reinterpret_cast<uint8_t*>(&(*plaintext)[0]), &outlen,
544 reinterpret_cast<const uint8_t*>(ciphertext.data() + GCM_NONCE_BYTES),
545 plaintext->size())) {
549 if (outlen != static_cast<int>(plaintext->size())) {
550 LOG(ERROR) << "GCM plaintext length should be " << plaintext->size() << " was " << outlen;
553 if (1 != EVP_CIPHER_CTX_ctrl(ctx.get(), EVP_CTRL_GCM_SET_TAG, GCM_MAC_BYTES,
554 const_cast<void*>(reinterpret_cast<const void*>(
555 ciphertext.data() + GCM_NONCE_BYTES + plaintext->size())))) {
559 if (1 != EVP_DecryptFinal_ex(ctx.get(),
560 reinterpret_cast<uint8_t*>(&(*plaintext)[0] + plaintext->size()),
566 LOG(ERROR) << "GCM EncryptFinal should be 0, was " << outlen;
572 bool storeKey(const std::string& dir, const KeyAuthentication& auth, const KeyBuffer& key) {
573 if (TEMP_FAILURE_RETRY(mkdir(dir.c_str(), 0700)) == -1) {
574 PLOG(ERROR) << "key mkdir " << dir;
577 if (!writeStringToFile(kCurrentVersion, dir + "/" + kFn_version)) return false;
578 std::string secdiscardable_hash;
579 if (!createSecdiscardable(dir + "/" + kFn_secdiscardable, &secdiscardable_hash)) return false;
580 std::string stretching = getStretching(auth);
581 if (!writeStringToFile(stretching, dir + "/" + kFn_stretching)) return false;
583 if (!generateAppId(auth, stretching, secdiscardable_hash, &appId)) return false;
584 std::string encryptedKey;
585 if (auth.usesKeymaster()) {
587 if (!keymaster) return false;
589 if (!generateKeyStorageKey(keymaster, appId, &kmKey)) return false;
590 if (!writeStringToFile(kmKey, dir + "/" + kFn_keymaster_key_blob)) return false;
591 km::AuthorizationSet keyParams = beginParams(appId);
592 if (!encryptWithKeymasterKey(keymaster, dir, keyParams, key, &encryptedKey)) return false;
594 if (!encryptWithoutKeymaster(appId, key, &encryptedKey)) return false;
596 if (!writeStringToFile(encryptedKey, dir + "/" + kFn_encrypted_key)) return false;
597 if (!FsyncDirectory(dir)) return false;
601 bool storeKeyAtomically(const std::string& key_path, const std::string& tmp_path,
602 const KeyAuthentication& auth, const KeyBuffer& key) {
603 if (pathExists(key_path)) {
604 LOG(ERROR) << "Already exists, cannot create key at: " << key_path;
607 if (pathExists(tmp_path)) {
608 LOG(DEBUG) << "Already exists, destroying: " << tmp_path;
609 destroyKey(tmp_path); // May be partially created so ignore errors
611 if (!storeKey(tmp_path, auth, key)) return false;
613 if (!RenameKeyDir(tmp_path, key_path)) {
614 PLOG(ERROR) << "Unable to move new key to location: " << key_path;
617 if (!FsyncParentDirectory(key_path)) return false;
618 LOG(DEBUG) << "Created key: " << key_path;
622 bool retrieveKey(const std::string& dir, const KeyAuthentication& auth, KeyBuffer* key) {
624 if (!readFileToString(dir + "/" + kFn_version, &version)) return false;
625 if (version != kCurrentVersion) {
626 LOG(ERROR) << "Version mismatch, expected " << kCurrentVersion << " got " << version;
629 std::string secdiscardable_hash;
630 if (!readSecdiscardable(dir + "/" + kFn_secdiscardable, &secdiscardable_hash)) return false;
631 std::string stretching;
632 if (!readFileToString(dir + "/" + kFn_stretching, &stretching)) return false;
634 if (!generateAppId(auth, stretching, secdiscardable_hash, &appId)) return false;
635 std::string encryptedMessage;
636 if (!readFileToString(dir + "/" + kFn_encrypted_key, &encryptedMessage)) return false;
637 if (auth.usesKeymaster()) {
639 if (!keymaster) return false;
640 km::AuthorizationSet keyParams = beginParams(appId);
641 if (!decryptWithKeymasterKey(keymaster, dir, keyParams, encryptedMessage, key))
644 if (!decryptWithoutKeymaster(appId, encryptedMessage, key)) return false;
649 static bool DeleteKeymasterKey(const std::string& blob_file) {
651 if (!readFileToString(blob_file, &blob)) return false;
653 if (!keymaster) return false;
654 LOG(DEBUG) << "Deleting key " << blob_file << " from Keymaster";
655 if (!keymaster.deleteKey(blob)) return false;
659 bool runSecdiscardSingle(const std::string& file) {
660 if (ForkExecvp(std::vector<std::string>{kSecdiscardPath, "--", file}) != 0) {
661 LOG(ERROR) << "secdiscard failed";
667 static bool recursiveDeleteKey(const std::string& dir) {
668 if (ForkExecvp(std::vector<std::string>{kRmPath, "-rf", dir}) != 0) {
669 LOG(ERROR) << "recursive delete failed";
675 bool destroyKey(const std::string& dir) {
678 CancelPendingKeyCommit(dir);
680 auto secdiscard_cmd = std::vector<std::string>{
683 dir + "/" + kFn_encrypted_key,
684 dir + "/" + kFn_secdiscardable,
686 // Try each thing, even if previous things failed.
688 for (auto& fn : {kFn_keymaster_key_blob, kFn_keymaster_key_blob_upgraded}) {
689 auto blob_file = dir + "/" + fn;
690 if (pathExists(blob_file)) {
691 success &= DeleteKeymasterKey(blob_file);
692 secdiscard_cmd.push_back(blob_file);
695 if (ForkExecvp(secdiscard_cmd) != 0) {
696 LOG(ERROR) << "secdiscard failed";
699 success &= recursiveDeleteKey(dir);
703 bool setKeyStorageBindingSeed(const std::vector<uint8_t>& seed) {
704 const std::lock_guard<std::mutex> scope_lock(storage_binding_info.guard);
705 switch (storage_binding_info.state) {
706 case StorageBindingInfo::State::UNINITIALIZED:
707 storage_binding_info.state = StorageBindingInfo::State::IN_USE;
708 storage_binding_info.seed = seed;
709 android::base::SetProperty("vold.storage_seed_bound", "1");
711 case StorageBindingInfo::State::IN_USE:
712 LOG(ERROR) << "key storage binding seed already set";
714 case StorageBindingInfo::State::NOT_USED:
715 LOG(ERROR) << "key storage already in use without binding";
722 } // namespace android