From e9afc3de0fe1df795cc2f8cfab489177252812be Mon Sep 17 00:00:00 2001 From: Ethan Yonker Date: Thu, 30 Aug 2018 15:16:27 -0500 Subject: Decrypt FBE on 9.0 (backwards compatible) Building in 9.0 may require you to add a flag to your twrp fstab with the fileencryption details like: fileencryption=ice:aes-256-heh Verify this against your device's stock fstab of course. Change-Id: If9286f5d5787280814daca9fbc8f5191ff26a839 --- crypto/ext4crypt/KeyStorage4.cpp | 598 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 598 insertions(+) create mode 100644 crypto/ext4crypt/KeyStorage4.cpp (limited to 'crypto/ext4crypt/KeyStorage4.cpp') diff --git a/crypto/ext4crypt/KeyStorage4.cpp b/crypto/ext4crypt/KeyStorage4.cpp new file mode 100644 index 000000000..28efdf1a9 --- /dev/null +++ b/crypto/ext4crypt/KeyStorage4.cpp @@ -0,0 +1,598 @@ +/* + * Copyright (C) 2016 The Android Open Source Project + * + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + +#include "KeyStorage4.h" + +#include "Keymaster4.h" +#include "ScryptParameters.h" +#include "Utils.h" + +#include + +#include +#include +#include +#include +#include +#include + +#include +#include +#include + +#include +//#include +#include + +#include + +#include +#include +#include + +#include +#define ERROR 1 +#define LOG(x) std::cout +#define PLOG(x) std::cout + +extern "C" { + +#include "crypto_scrypt.h" +} + +namespace android { +namespace vold { + +const KeyAuthentication kEmptyAuthentication{"", ""}; + +static constexpr size_t AES_KEY_BYTES = 32; +static constexpr size_t GCM_NONCE_BYTES = 12; +static constexpr size_t GCM_MAC_BYTES = 16; +static constexpr size_t SALT_BYTES = 1 << 4; +static constexpr size_t SECDISCARDABLE_BYTES = 1 << 14; +static constexpr size_t STRETCHED_BYTES = 1 << 6; + +static constexpr uint32_t AUTH_TIMEOUT = 30; // Seconds + +static const char* kCurrentVersion = "1"; +static const char* kRmPath = "/system/bin/rm"; +static const char* kSecdiscardPath = "/system/bin/secdiscard"; +static const char* kStretch_none = "none"; +static const char* kStretch_nopassword = "nopassword"; +static const std::string kStretchPrefix_scrypt = "scrypt "; +static const char* kHashPrefix_secdiscardable = "Android secdiscardable SHA512"; +static const char* kHashPrefix_keygen = "Android key wrapping key generation SHA512"; +static const char* kFn_encrypted_key = "encrypted_key"; +static const char* kFn_keymaster_key_blob = "keymaster_key_blob"; +static const char* kFn_keymaster_key_blob_upgraded = "keymaster_key_blob_upgraded"; +static const char* kFn_salt = "salt"; +static const char* kFn_secdiscardable = "secdiscardable"; +static const char* kFn_stretching = "stretching"; +static const char* kFn_version = "version"; + +static bool checkSize(const std::string& kind, size_t actual, size_t expected) { + if (actual != expected) { + LOG(ERROR) << "Wrong number of bytes in " << kind << ", expected " << expected << " got " + << actual << std::endl; + return false; + } + return true; +} + +static void hashWithPrefix(char const* prefix, const std::string& tohash, std::string* res) { + SHA512_CTX c; + + SHA512_Init(&c); + // Personalise the hashing by introducing a fixed prefix. + // Hashing applications should use personalization except when there is a + // specific reason not to; see section 4.11 of https://www.schneier.com/skein1.3.pdf + std::string hashingPrefix = prefix; + hashingPrefix.resize(SHA512_CBLOCK); + SHA512_Update(&c, hashingPrefix.data(), hashingPrefix.size()); + SHA512_Update(&c, tohash.data(), tohash.size()); + res->assign(SHA512_DIGEST_LENGTH, '\0'); + SHA512_Final(reinterpret_cast(&(*res)[0]), &c); +} + +static bool generateKeymasterKey(Keymaster& keymaster, const KeyAuthentication& auth, + const std::string& appId, std::string* key) { + auto paramBuilder = km::AuthorizationSetBuilder() + .AesEncryptionKey(AES_KEY_BYTES * 8) + .GcmModeMinMacLen(GCM_MAC_BYTES * 8) + .Authorization(km::TAG_APPLICATION_ID, km::support::blob2hidlVec(appId)); + if (auth.token.empty()) { + LOG(DEBUG) << "Creating key that doesn't need auth token" << std::endl; + paramBuilder.Authorization(km::TAG_NO_AUTH_REQUIRED); + } else { + LOG(DEBUG) << "Auth token required for key" << std::endl; + if (auth.token.size() != sizeof(hw_auth_token_t)) { + LOG(ERROR) << "Auth token should be " << sizeof(hw_auth_token_t) << " bytes, was " + << auth.token.size() << " bytes" << std::endl; + return false; + } + const hw_auth_token_t* at = reinterpret_cast(auth.token.data()); + paramBuilder.Authorization(km::TAG_USER_SECURE_ID, at->user_id); + paramBuilder.Authorization(km::TAG_USER_AUTH_TYPE, km::HardwareAuthenticatorType::PASSWORD); + paramBuilder.Authorization(km::TAG_AUTH_TIMEOUT, AUTH_TIMEOUT); + } + return keymaster.generateKey(paramBuilder, key); +} + +static std::pair beginParams( + const KeyAuthentication& auth, const std::string& appId) { + auto paramBuilder = km::AuthorizationSetBuilder() + .GcmModeMacLen(GCM_MAC_BYTES * 8) + .Authorization(km::TAG_APPLICATION_ID, km::support::blob2hidlVec(appId)); + km::HardwareAuthToken authToken; + if (!auth.token.empty()) { + LOG(DEBUG) << "Supplying auth token to Keymaster" << std::endl; + authToken = km::support::hidlVec2AuthToken(km::support::blob2hidlVec(auth.token)); + } + return {paramBuilder, authToken}; +} + +static bool readFileToString(const std::string& filename, std::string* result) { + if (!android::base::ReadFileToString(filename, result)) { + PLOG(ERROR) << "Failed to read from " << filename << std::endl; + return false; + } + return true; +} + +static bool writeStringToFile(const std::string& payload, const std::string& filename) { + PLOG(ERROR) << __FUNCTION__ << " called for " << filename << " and being skipped\n"; + return true; + android::base::unique_fd fd(TEMP_FAILURE_RETRY( + open(filename.c_str(), O_WRONLY | O_CREAT | O_NOFOLLOW | O_TRUNC | O_CLOEXEC, 0666))); + if (fd == -1) { + PLOG(ERROR) << "Failed to open " << filename; + return false; + } + if (!android::base::WriteStringToFd(payload, fd)) { + PLOG(ERROR) << "Failed to write to " << filename; + unlink(filename.c_str()); + return false; + } + // fsync as close won't guarantee flush data + // see close(2), fsync(2) and b/68901441 + if (fsync(fd) == -1) { + if (errno == EROFS || errno == EINVAL) { + PLOG(WARNING) << "Skip fsync " << filename + << " on a file system does not support synchronization"; + } else { + PLOG(ERROR) << "Failed to fsync " << filename; + unlink(filename.c_str()); + return false; + } + } + return true; +} + +static bool readRandomBytesOrLog(size_t count, std::string* out) { + auto status = ReadRandomBytes(count, *out); + if (status != OK) { + LOG(ERROR) << "Random read failed with status: " << status << std::endl; + return false; + } + return true; +} + +bool createSecdiscardable(const std::string& filename, std::string* hash) { + std::string secdiscardable; + if (!readRandomBytesOrLog(SECDISCARDABLE_BYTES, &secdiscardable)) return false; + if (!writeStringToFile(secdiscardable, filename)) return false; + hashWithPrefix(kHashPrefix_secdiscardable, secdiscardable, hash); + return true; +} + +bool readSecdiscardable(const std::string& filename, std::string* hash) { + std::string secdiscardable; + if (!readFileToString(filename, &secdiscardable)) return false; + hashWithPrefix(kHashPrefix_secdiscardable, secdiscardable, hash); + return true; +} + +static KeymasterOperation begin(Keymaster& keymaster, const std::string& dir, + km::KeyPurpose purpose, const km::AuthorizationSet& keyParams, + const km::AuthorizationSet& opParams, + const km::HardwareAuthToken& authToken, + km::AuthorizationSet* outParams) { + auto kmKeyPath = dir + "/" + kFn_keymaster_key_blob; + std::string kmKey; + if (!readFileToString(kmKeyPath, &kmKey)) return KeymasterOperation(); + km::AuthorizationSet inParams(keyParams); + inParams.append(opParams.begin(), opParams.end()); + for (;;) { + auto opHandle = keymaster.begin(purpose, kmKey, inParams, authToken, outParams); + if (opHandle) { + return opHandle; + } + if (opHandle.errorCode() != km::ErrorCode::KEY_REQUIRES_UPGRADE) return opHandle; + LOG(DEBUG) << "Upgrading key in memory only: " << dir << std::endl; + std::string newKey; + if (!keymaster.upgradeKey(kmKey, keyParams, &newKey)) return KeymasterOperation(); + /*auto newKeyPath = dir + "/" + kFn_keymaster_key_blob_upgraded; + if (!writeStringToFile(newKey, newKeyPath)) return KeymasterOperation(); + if (rename(newKeyPath.c_str(), kmKeyPath.c_str()) != 0) { + PLOG(ERROR) << "Unable to move upgraded key to location: " << kmKeyPath; + return KeymasterOperation(); + } + if (!keymaster.deleteKey(kmKey)) { + LOG(ERROR) << "Key deletion failed during upgrade, continuing anyway: " << dir; + }*/ + kmKey = newKey; + LOG(INFO) << "Key upgraded in memory but not updated in folder: " << dir << std::endl; + } +} + +static bool encryptWithKeymasterKey(Keymaster& keymaster, const std::string& dir, + const km::AuthorizationSet& keyParams, + const km::HardwareAuthToken& authToken, + const KeyBuffer& message, std::string* ciphertext) { + km::AuthorizationSet opParams; + km::AuthorizationSet outParams; + auto opHandle = + begin(keymaster, dir, km::KeyPurpose::ENCRYPT, keyParams, opParams, authToken, &outParams); + if (!opHandle) return false; + auto nonceBlob = outParams.GetTagValue(km::TAG_NONCE); + if (!nonceBlob.isOk()) { + LOG(ERROR) << "GCM encryption but no nonce generated" << std::endl; + return false; + } + // nonceBlob here is just a pointer into existing data, must not be freed + std::string nonce(reinterpret_cast(&nonceBlob.value()[0]), + nonceBlob.value().size()); + if (!checkSize("nonce", nonce.size(), GCM_NONCE_BYTES)) return false; + std::string body; + if (!opHandle.updateCompletely(message, &body)) return false; + + std::string mac; + if (!opHandle.finish(&mac)) return false; + if (!checkSize("mac", mac.size(), GCM_MAC_BYTES)) return false; + *ciphertext = nonce + body + mac; + return true; +} + +static bool decryptWithKeymasterKey(Keymaster& keymaster, const std::string& dir, + const km::AuthorizationSet& keyParams, + const km::HardwareAuthToken& authToken, + const std::string& ciphertext, KeyBuffer* message) { + auto nonce = ciphertext.substr(0, GCM_NONCE_BYTES); + auto bodyAndMac = ciphertext.substr(GCM_NONCE_BYTES); + auto opParams = km::AuthorizationSetBuilder().Authorization(km::TAG_NONCE, + km::support::blob2hidlVec(nonce)); + auto opHandle = + begin(keymaster, dir, km::KeyPurpose::DECRYPT, keyParams, opParams, authToken, nullptr); + if (!opHandle) return false; + if (!opHandle.updateCompletely(bodyAndMac, message)) return false; + if (!opHandle.finish(nullptr)) return false; + return true; +} + +static std::string getStretching(const KeyAuthentication& auth) { + if (!auth.usesKeymaster()) { + return kStretch_none; + } else if (auth.secret.empty()) { + return kStretch_nopassword; + } else { + char paramstr[PROPERTY_VALUE_MAX]; + + property_get(SCRYPT_PROP, paramstr, SCRYPT_DEFAULTS); + return std::string() + kStretchPrefix_scrypt + paramstr; + } +} + +static bool stretchingNeedsSalt(const std::string& stretching) { + return stretching != kStretch_nopassword && stretching != kStretch_none; +} + +static bool stretchSecret(const std::string& stretching, const std::string& secret, + const std::string& salt, std::string* stretched) { + if (stretching == kStretch_nopassword) { + if (!secret.empty()) { + LOG(WARNING) << "Password present but stretching is nopassword" << std::endl; + // Continue anyway + } + stretched->clear(); + } else if (stretching == kStretch_none) { + *stretched = secret; + } else if (std::equal(kStretchPrefix_scrypt.begin(), kStretchPrefix_scrypt.end(), + stretching.begin())) { + int Nf, rf, pf; + if (!parse_scrypt_parameters(stretching.substr(kStretchPrefix_scrypt.size()).c_str(), &Nf, + &rf, &pf)) { + LOG(ERROR) << "Unable to parse scrypt params in stretching: " << stretching << std::endl; + return false; + } + stretched->assign(STRETCHED_BYTES, '\0'); + if (crypto_scrypt(reinterpret_cast(secret.data()), secret.size(), + reinterpret_cast(salt.data()), salt.size(), 1 << Nf, + 1 << rf, 1 << pf, reinterpret_cast(&(*stretched)[0]), + stretched->size()) != 0) { + LOG(ERROR) << "scrypt failed with params: " << stretching << std::endl; + return false; + } + } else { + LOG(ERROR) << "Unknown stretching type: " << stretching << std::endl; + return false; + } + return true; +} + +static bool generateAppId(const KeyAuthentication& auth, const std::string& stretching, + const std::string& salt, const std::string& secdiscardable_hash, + std::string* appId) { + std::string stretched; + if (!stretchSecret(stretching, auth.secret, salt, &stretched)) return false; + *appId = secdiscardable_hash + stretched; + return true; +} + +static void logOpensslError() { + LOG(ERROR) << "Openssl error: " << ERR_get_error() << std::endl; +} + +static bool encryptWithoutKeymaster(const std::string& preKey, const KeyBuffer& plaintext, + std::string* ciphertext) { + std::string key; + hashWithPrefix(kHashPrefix_keygen, preKey, &key); + key.resize(AES_KEY_BYTES); + if (!readRandomBytesOrLog(GCM_NONCE_BYTES, ciphertext)) return false; + auto ctx = std::unique_ptr( + EVP_CIPHER_CTX_new(), EVP_CIPHER_CTX_free); + if (!ctx) { + logOpensslError(); + return false; + } + if (1 != EVP_EncryptInit_ex(ctx.get(), EVP_aes_256_gcm(), NULL, + reinterpret_cast(key.data()), + reinterpret_cast(ciphertext->data()))) { + logOpensslError(); + return false; + } + ciphertext->resize(GCM_NONCE_BYTES + plaintext.size() + GCM_MAC_BYTES); + int outlen; + if (1 != EVP_EncryptUpdate( + ctx.get(), reinterpret_cast(&(*ciphertext)[0] + GCM_NONCE_BYTES), + &outlen, reinterpret_cast(plaintext.data()), plaintext.size())) { + logOpensslError(); + return false; + } + if (outlen != static_cast(plaintext.size())) { + LOG(ERROR) << "GCM ciphertext length should be " << plaintext.size() << " was " << outlen << std::endl; + return false; + } + if (1 != EVP_EncryptFinal_ex( + ctx.get(), + reinterpret_cast(&(*ciphertext)[0] + GCM_NONCE_BYTES + plaintext.size()), + &outlen)) { + logOpensslError(); + return false; + } + if (outlen != 0) { + LOG(ERROR) << "GCM EncryptFinal should be 0, was " << outlen << std::endl; + return false; + } + if (1 != EVP_CIPHER_CTX_ctrl(ctx.get(), EVP_CTRL_GCM_GET_TAG, GCM_MAC_BYTES, + reinterpret_cast(&(*ciphertext)[0] + GCM_NONCE_BYTES + + plaintext.size()))) { + logOpensslError(); + return false; + } + return true; +} + +static bool decryptWithoutKeymaster(const std::string& preKey, const std::string& ciphertext, + KeyBuffer* plaintext) { + if (ciphertext.size() < GCM_NONCE_BYTES + GCM_MAC_BYTES) { + LOG(ERROR) << "GCM ciphertext too small: " << ciphertext.size() << std::endl; + return false; + } + std::string key; + hashWithPrefix(kHashPrefix_keygen, preKey, &key); + key.resize(AES_KEY_BYTES); + auto ctx = std::unique_ptr( + EVP_CIPHER_CTX_new(), EVP_CIPHER_CTX_free); + if (!ctx) { + logOpensslError(); + return false; + } + if (1 != EVP_DecryptInit_ex(ctx.get(), EVP_aes_256_gcm(), NULL, + reinterpret_cast(key.data()), + reinterpret_cast(ciphertext.data()))) { + logOpensslError(); + return false; + } + *plaintext = KeyBuffer(ciphertext.size() - GCM_NONCE_BYTES - GCM_MAC_BYTES); + int outlen; + if (1 != EVP_DecryptUpdate(ctx.get(), reinterpret_cast(&(*plaintext)[0]), &outlen, + reinterpret_cast(ciphertext.data() + GCM_NONCE_BYTES), + plaintext->size())) { + logOpensslError(); + return false; + } + if (outlen != static_cast(plaintext->size())) { + LOG(ERROR) << "GCM plaintext length should be " << plaintext->size() << " was " << outlen << std::endl; + return false; + } + if (1 != EVP_CIPHER_CTX_ctrl(ctx.get(), EVP_CTRL_GCM_SET_TAG, GCM_MAC_BYTES, + const_cast(reinterpret_cast( + ciphertext.data() + GCM_NONCE_BYTES + plaintext->size())))) { + logOpensslError(); + return false; + } + if (1 != EVP_DecryptFinal_ex(ctx.get(), + reinterpret_cast(&(*plaintext)[0] + plaintext->size()), + &outlen)) { + logOpensslError(); + return false; + } + if (outlen != 0) { + LOG(ERROR) << "GCM EncryptFinal should be 0, was " << outlen << std::endl; + return false; + } + return true; +} + +bool pathExists(const std::string& path) { + return access(path.c_str(), F_OK) == 0; +} + +bool storeKey(const std::string& dir, const KeyAuthentication& auth, const KeyBuffer& key) { + if (TEMP_FAILURE_RETRY(mkdir(dir.c_str(), 0700)) == -1) { + PLOG(ERROR) << "key mkdir " << dir << std::endl; + return false; + } + if (!writeStringToFile(kCurrentVersion, dir + "/" + kFn_version)) return false; + std::string secdiscardable_hash; + if (!createSecdiscardable(dir + "/" + kFn_secdiscardable, &secdiscardable_hash)) return false; + std::string stretching = getStretching(auth); + if (!writeStringToFile(stretching, dir + "/" + kFn_stretching)) return false; + std::string salt; + if (stretchingNeedsSalt(stretching)) { + if (ReadRandomBytes(SALT_BYTES, salt) != OK) { + LOG(ERROR) << "Random read failed" << std::endl; + return false; + } + if (!writeStringToFile(salt, dir + "/" + kFn_salt)) return false; + } + std::string appId; + if (!generateAppId(auth, stretching, salt, secdiscardable_hash, &appId)) return false; + std::string encryptedKey; + if (auth.usesKeymaster()) { + Keymaster keymaster; + if (!keymaster) return false; + std::string kmKey; + if (!generateKeymasterKey(keymaster, auth, appId, &kmKey)) return false; + if (!writeStringToFile(kmKey, dir + "/" + kFn_keymaster_key_blob)) return false; + km::AuthorizationSet keyParams; + km::HardwareAuthToken authToken; + std::tie(keyParams, authToken) = beginParams(auth, appId); + if (!encryptWithKeymasterKey(keymaster, dir, keyParams, authToken, key, &encryptedKey)) + return false; + } else { + if (!encryptWithoutKeymaster(appId, key, &encryptedKey)) return false; + } + if (!writeStringToFile(encryptedKey, dir + "/" + kFn_encrypted_key)) return false; + return true; +} + +bool storeKeyAtomically(const std::string& key_path, const std::string& tmp_path, + const KeyAuthentication& auth, const KeyBuffer& key) { + if (pathExists(key_path)) { + LOG(ERROR) << "Already exists, cannot create key at: " << key_path << std::endl; + return false; + } + if (pathExists(tmp_path)) { + LOG(DEBUG) << "Already exists, destroying: " << tmp_path << std::endl; + destroyKey(tmp_path); // May be partially created so ignore errors + } + if (!storeKey(tmp_path, auth, key)) return false; + if (rename(tmp_path.c_str(), key_path.c_str()) != 0) { + PLOG(ERROR) << "Unable to move new key to location: " << key_path << std::endl; + return false; + } + LOG(DEBUG) << "Created key: " << key_path << std::endl; + return true; +} + +bool retrieveKey(const std::string& dir, const KeyAuthentication& auth, KeyBuffer* key) { + std::string version; + if (!readFileToString(dir + "/" + kFn_version, &version)) return false; + if (version != kCurrentVersion) { + LOG(ERROR) << "Version mismatch, expected " << kCurrentVersion << " got " << version << std::endl; + return false; + } + std::string secdiscardable_hash; + if (!readSecdiscardable(dir + "/" + kFn_secdiscardable, &secdiscardable_hash)) return false; + std::string stretching; + if (!readFileToString(dir + "/" + kFn_stretching, &stretching)) return false; + std::string salt; + if (stretchingNeedsSalt(stretching)) { + if (!readFileToString(dir + "/" + kFn_salt, &salt)) return false; + } + std::string appId; + if (!generateAppId(auth, stretching, salt, secdiscardable_hash, &appId)) return false; + std::string encryptedMessage; + if (!readFileToString(dir + "/" + kFn_encrypted_key, &encryptedMessage)) return false; + if (auth.usesKeymaster()) { + Keymaster keymaster; + if (!keymaster) return false; + km::AuthorizationSet keyParams; + km::HardwareAuthToken authToken; + std::tie(keyParams, authToken) = beginParams(auth, appId); + if (!decryptWithKeymasterKey(keymaster, dir, keyParams, authToken, encryptedMessage, key)) + return false; + } else { + if (!decryptWithoutKeymaster(appId, encryptedMessage, key)) return false; + } + return true; +} + +static bool deleteKey(const std::string& dir) { + LOG(DEBUG) << "not deleting key in " << __FILE__ << std::endl; + return true; + std::string kmKey; + if (!readFileToString(dir + "/" + kFn_keymaster_key_blob, &kmKey)) return false; + Keymaster keymaster; + if (!keymaster) return false; + if (!keymaster.deleteKey(kmKey)) return false; + return true; +} + +bool runSecdiscardSingle(const std::string& file) { + if (ForkExecvp(std::vector{kSecdiscardPath, "--", file}) != 0) { + LOG(ERROR) << "secdiscard failed" << std::endl; + return false; + } + return true; +} + +static bool recursiveDeleteKey(const std::string& dir) { + LOG(DEBUG) << "not recursively deleting key in " << __FILE__ << std::endl; + return true; + if (ForkExecvp(std::vector{kRmPath, "-rf", dir}) != 0) { + LOG(ERROR) << "recursive delete failed" << std::endl; + return false; + } + return true; +} + +bool destroyKey(const std::string& dir) { + LOG(DEBUG) << "not destroying key in " << __FILE__ << std::endl; + return true; + bool success = true; + // Try each thing, even if previous things failed. + bool uses_km = pathExists(dir + "/" + kFn_keymaster_key_blob); + if (uses_km) { + success &= deleteKey(dir); + } + auto secdiscard_cmd = std::vector{ + kSecdiscardPath, "--", dir + "/" + kFn_encrypted_key, dir + "/" + kFn_secdiscardable, + }; + if (uses_km) { + secdiscard_cmd.emplace_back(dir + "/" + kFn_keymaster_key_blob); + } + if (ForkExecvp(secdiscard_cmd) != 0) { + LOG(ERROR) << "secdiscard failed" << std::endl; + success = false; + } + success &= recursiveDeleteKey(dir); + return success; +} + +} // namespace vold +} // namespace android -- cgit v1.2.3